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<header> 91 <div class="header-container"> 92 <h1>Node.js v14.20.1 documentation</h1> 93 <button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden> 94 <svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24"> 95 <path fill="none" d="M0 0h24v24H0z" /> 96 <path d="M11.1 12.08c-2.33-4.51-.5-8.48.53-10.07C6.27 2.2 1.98 6.59 1.98 12c0 .14.02.28.02.42.62-.27 1.29-.42 2-.42 1.66 0 3.18.83 4.1 2.15A4.01 4.01 0 0111 18c0 1.52-.87 2.83-2.12 3.51.98.32 2.03.5 3.11.5 3.5 0 6.58-1.8 8.37-4.52-2.36.23-6.98-.97-9.26-5.41z"/> 97 <path d="M7 16h-.18C6.4 14.84 5.3 14 4 14c-1.66 0-3 1.34-3 3s1.34 3 3 3h3c1.1 0 2-.9 2-2s-.9-2-2-2z"/> 98 </svg> 99 <svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24"> 100 <path d="M0 0h24v24H0z" fill="none" /> 101 <path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 10.5H1v2h3v-2zm9-9.95h-2V3.5h2V.55zm7.45 3.91l-1.41-1.41-1.79 1.79 1.41 1.41 1.79-1.79zm-3.21 13.7l1.79 1.8 1.41-1.41-1.8-1.79-1.4 1.4zM20 10.5v2h3v-2h-3zm-8-5c-3.31 0-6 2.69-6 6s2.69 6 6 6 6-2.69 6-6-2.69-6-6-6zm-1 16.95h2V19.5h-2v2.95zm-7.45-3.91l1.41 1.41 1.79-1.8-1.41-1.41-1.79 1.8z"/> 102 </svg> 103 </button> 104 </div> 105 <div id="gtoc"> 106 <ul> 107 <li> 108 <a href="index.html">Index</a> 109 </li> 110 <li> 111 <a href="all.html">View on single page</a> 112 </li> 113 <li> 114 <a href="crypto.json">View as JSON</a> 115 </li> 116 117 <li class="version-picker"> 118 <a href="#">View another version <span>▼</span></a> 119 <ol class="version-picker"><li><a href="https://nodejs.org/docs/latest-v18.x/api/crypto.html">18.x</a></li> 120<li><a href="https://nodejs.org/docs/latest-v17.x/api/crypto.html">17.x</a></li> 121<li><a href="https://nodejs.org/docs/latest-v16.x/api/crypto.html">16.x <b>LTS</b></a></li> 122<li><a href="https://nodejs.org/docs/latest-v15.x/api/crypto.html">15.x</a></li> 123<li><a href="https://nodejs.org/docs/latest-v14.x/api/crypto.html">14.x <b>LTS</b></a></li> 124<li><a href="https://nodejs.org/docs/latest-v13.x/api/crypto.html">13.x</a></li> 125<li><a href="https://nodejs.org/docs/latest-v12.x/api/crypto.html">12.x <b>LTS</b></a></li> 126<li><a href="https://nodejs.org/docs/latest-v11.x/api/crypto.html">11.x</a></li> 127<li><a href="https://nodejs.org/docs/latest-v10.x/api/crypto.html">10.x</a></li> 128<li><a href="https://nodejs.org/docs/latest-v9.x/api/crypto.html">9.x</a></li> 129<li><a href="https://nodejs.org/docs/latest-v8.x/api/crypto.html">8.x</a></li> 130<li><a href="https://nodejs.org/docs/latest-v7.x/api/crypto.html">7.x</a></li> 131<li><a href="https://nodejs.org/docs/latest-v6.x/api/crypto.html">6.x</a></li> 132<li><a href="https://nodejs.org/docs/latest-v5.x/api/crypto.html">5.x</a></li> 133<li><a href="https://nodejs.org/docs/latest-v4.x/api/crypto.html">4.x</a></li> 134<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/crypto.html">0.12.x</a></li> 135<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/crypto.html">0.10.x</a></li></ol> 136 </li> 137 138 <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/master/doc/api/crypto.md">Edit on GitHub</a></li> 139 </ul> 140 </div> 141 <hr> 142 </header> 143 144 <details id="toc" open><summary>Table of contents</summary><ul> 145<li><span class="stability_2"><a href="#crypto_crypto">Crypto</a></span> 146<ul> 147<li><a href="#crypto_determining_if_crypto_support_is_unavailable">Determining if crypto support is unavailable</a></li> 148<li><a href="#crypto_class_certificate">Class: <code>Certificate</code></a> 149<ul> 150<li><a href="#crypto_certificate_exportchallenge_spkac"><code>Certificate.exportChallenge(spkac)</code></a></li> 151<li><a href="#crypto_certificate_exportpublickey_spkac_encoding"><code>Certificate.exportPublicKey(spkac[, encoding])</code></a></li> 152<li><a href="#crypto_certificate_verifyspkac_spkac"><code>Certificate.verifySpkac(spkac)</code></a></li> 153<li><span class="stability_0"><a href="#crypto_legacy_api">Legacy API</a></span> 154<ul> 155<li><a href="#crypto_new_crypto_certificate"><code>new crypto.Certificate()</code></a></li> 156<li><a href="#crypto_certificate_exportchallenge_spkac_1"><code>certificate.exportChallenge(spkac)</code></a></li> 157<li><a href="#crypto_certificate_exportpublickey_spkac"><code>certificate.exportPublicKey(spkac)</code></a></li> 158<li><a href="#crypto_certificate_verifyspkac_spkac_1"><code>certificate.verifySpkac(spkac)</code></a></li> 159</ul> 160</li> 161</ul> 162</li> 163<li><a href="#crypto_class_cipher">Class: <code>Cipher</code></a> 164<ul> 165<li><a href="#crypto_cipher_final_outputencoding"><code>cipher.final([outputEncoding])</code></a></li> 166<li><a href="#crypto_cipher_getauthtag"><code>cipher.getAuthTag()</code></a></li> 167<li><a href="#crypto_cipher_setaad_buffer_options"><code>cipher.setAAD(buffer[, options])</code></a></li> 168<li><a href="#crypto_cipher_setautopadding_autopadding"><code>cipher.setAutoPadding([autoPadding])</code></a></li> 169<li><a href="#crypto_cipher_update_data_inputencoding_outputencoding"><code>cipher.update(data[, inputEncoding][, outputEncoding])</code></a></li> 170</ul> 171</li> 172<li><a href="#crypto_class_decipher">Class: <code>Decipher</code></a> 173<ul> 174<li><a href="#crypto_decipher_final_outputencoding"><code>decipher.final([outputEncoding])</code></a></li> 175<li><a href="#crypto_decipher_setaad_buffer_options"><code>decipher.setAAD(buffer[, options])</code></a></li> 176<li><a href="#crypto_decipher_setauthtag_buffer"><code>decipher.setAuthTag(buffer)</code></a></li> 177<li><a href="#crypto_decipher_setautopadding_autopadding"><code>decipher.setAutoPadding([autoPadding])</code></a></li> 178<li><a href="#crypto_decipher_update_data_inputencoding_outputencoding"><code>decipher.update(data[, inputEncoding][, outputEncoding])</code></a></li> 179</ul> 180</li> 181<li><a href="#crypto_class_diffiehellman">Class: <code>DiffieHellman</code></a> 182<ul> 183<li><a href="#crypto_diffiehellman_computesecret_otherpublickey_inputencoding_outputencoding"><code>diffieHellman.computeSecret(otherPublicKey[, inputEncoding][, outputEncoding])</code></a></li> 184<li><a href="#crypto_diffiehellman_generatekeys_encoding"><code>diffieHellman.generateKeys([encoding])</code></a></li> 185<li><a href="#crypto_diffiehellman_getgenerator_encoding"><code>diffieHellman.getGenerator([encoding])</code></a></li> 186<li><a href="#crypto_diffiehellman_getprime_encoding"><code>diffieHellman.getPrime([encoding])</code></a></li> 187<li><a href="#crypto_diffiehellman_getprivatekey_encoding"><code>diffieHellman.getPrivateKey([encoding])</code></a></li> 188<li><a href="#crypto_diffiehellman_getpublickey_encoding"><code>diffieHellman.getPublicKey([encoding])</code></a></li> 189<li><a href="#crypto_diffiehellman_setprivatekey_privatekey_encoding"><code>diffieHellman.setPrivateKey(privateKey[, encoding])</code></a></li> 190<li><a href="#crypto_diffiehellman_setpublickey_publickey_encoding"><code>diffieHellman.setPublicKey(publicKey[, encoding])</code></a></li> 191<li><a href="#crypto_diffiehellman_verifyerror"><code>diffieHellman.verifyError</code></a></li> 192</ul> 193</li> 194<li><a href="#crypto_class_diffiehellmangroup">Class: <code>DiffieHellmanGroup</code></a></li> 195<li><a href="#crypto_class_ecdh">Class: <code>ECDH</code></a> 196<ul> 197<li><a href="#crypto_static_method_ecdh_convertkey_key_curve_inputencoding_outputencoding_format">Static method: <code>ECDH.convertKey(key, curve[, inputEncoding[, outputEncoding[, format]]])</code></a></li> 198<li><a href="#crypto_ecdh_computesecret_otherpublickey_inputencoding_outputencoding"><code>ecdh.computeSecret(otherPublicKey[, inputEncoding][, outputEncoding])</code></a></li> 199<li><a href="#crypto_ecdh_generatekeys_encoding_format"><code>ecdh.generateKeys([encoding[, format]])</code></a></li> 200<li><a href="#crypto_ecdh_getprivatekey_encoding"><code>ecdh.getPrivateKey([encoding])</code></a></li> 201<li><a href="#crypto_ecdh_getpublickey_encoding_format"><code>ecdh.getPublicKey([encoding][, format])</code></a></li> 202<li><a href="#crypto_ecdh_setprivatekey_privatekey_encoding"><code>ecdh.setPrivateKey(privateKey[, encoding])</code></a></li> 203<li><span class="stability_0"><a href="#crypto_ecdh_setpublickey_publickey_encoding"><code>ecdh.setPublicKey(publicKey[, encoding])</code></a></span></li> 204</ul> 205</li> 206<li><a href="#crypto_class_hash">Class: <code>Hash</code></a> 207<ul> 208<li><a href="#crypto_hash_copy_options"><code>hash.copy([options])</code></a></li> 209<li><a href="#crypto_hash_digest_encoding"><code>hash.digest([encoding])</code></a></li> 210<li><a href="#crypto_hash_update_data_inputencoding"><code>hash.update(data[, inputEncoding])</code></a></li> 211</ul> 212</li> 213<li><a href="#crypto_class_hmac">Class: <code>Hmac</code></a> 214<ul> 215<li><a href="#crypto_hmac_digest_encoding"><code>hmac.digest([encoding])</code></a></li> 216<li><a href="#crypto_hmac_update_data_inputencoding"><code>hmac.update(data[, inputEncoding])</code></a></li> 217</ul> 218</li> 219<li><a href="#crypto_class_keyobject">Class: <code>KeyObject</code></a> 220<ul> 221<li><a href="#crypto_keyobject_asymmetrickeytype"><code>keyObject.asymmetricKeyType</code></a></li> 222<li><a href="#crypto_keyobject_export_options"><code>keyObject.export([options])</code></a></li> 223<li><a href="#crypto_keyobject_symmetrickeysize"><code>keyObject.symmetricKeySize</code></a></li> 224<li><a href="#crypto_keyobject_type"><code>keyObject.type</code></a></li> 225</ul> 226</li> 227<li><a href="#crypto_class_sign">Class: <code>Sign</code></a> 228<ul> 229<li><a href="#crypto_sign_sign_privatekey_outputencoding"><code>sign.sign(privateKey[, outputEncoding])</code></a></li> 230<li><a href="#crypto_sign_update_data_inputencoding"><code>sign.update(data[, inputEncoding])</code></a></li> 231</ul> 232</li> 233<li><a href="#crypto_class_verify">Class: <code>Verify</code></a> 234<ul> 235<li><a href="#crypto_verify_update_data_inputencoding"><code>verify.update(data[, inputEncoding])</code></a></li> 236<li><a href="#crypto_verify_verify_object_signature_signatureencoding"><code>verify.verify(object, signature[, signatureEncoding])</code></a></li> 237</ul> 238</li> 239<li><a href="#crypto_crypto_module_methods_and_properties"><code>crypto</code> module methods and properties</a> 240<ul> 241<li><a href="#crypto_crypto_constants"><code>crypto.constants</code></a></li> 242<li><span class="stability_0"><a href="#crypto_crypto_default_encoding"><code>crypto.DEFAULT_ENCODING</code></a></span></li> 243<li><span class="stability_0"><a href="#crypto_crypto_fips"><code>crypto.fips</code></a></span></li> 244<li><span class="stability_0"><a href="#crypto_crypto_createcipher_algorithm_password_options"><code>crypto.createCipher(algorithm, password[, options])</code></a></span></li> 245<li><a href="#crypto_crypto_createcipheriv_algorithm_key_iv_options"><code>crypto.createCipheriv(algorithm, key, iv[, options])</code></a></li> 246<li><span class="stability_0"><a href="#crypto_crypto_createdecipher_algorithm_password_options"><code>crypto.createDecipher(algorithm, password[, options])</code></a></span></li> 247<li><a href="#crypto_crypto_createdecipheriv_algorithm_key_iv_options"><code>crypto.createDecipheriv(algorithm, key, iv[, options])</code></a></li> 248<li><a href="#crypto_crypto_creatediffiehellman_prime_primeencoding_generator_generatorencoding"><code>crypto.createDiffieHellman(prime[, primeEncoding][, generator][, generatorEncoding])</code></a></li> 249<li><a href="#crypto_crypto_creatediffiehellman_primelength_generator"><code>crypto.createDiffieHellman(primeLength[, generator])</code></a></li> 250<li><a href="#crypto_crypto_creatediffiehellmangroup_name"><code>crypto.createDiffieHellmanGroup(name)</code></a></li> 251<li><a href="#crypto_crypto_createecdh_curvename"><code>crypto.createECDH(curveName)</code></a></li> 252<li><a href="#crypto_crypto_createhash_algorithm_options"><code>crypto.createHash(algorithm[, options])</code></a></li> 253<li><a href="#crypto_crypto_createhmac_algorithm_key_options"><code>crypto.createHmac(algorithm, key[, options])</code></a></li> 254<li><a href="#crypto_crypto_createprivatekey_key"><code>crypto.createPrivateKey(key)</code></a></li> 255<li><a href="#crypto_crypto_createpublickey_key"><code>crypto.createPublicKey(key)</code></a></li> 256<li><a href="#crypto_crypto_createsecretkey_key"><code>crypto.createSecretKey(key)</code></a></li> 257<li><a href="#crypto_crypto_createsign_algorithm_options"><code>crypto.createSign(algorithm[, options])</code></a></li> 258<li><a href="#crypto_crypto_createverify_algorithm_options"><code>crypto.createVerify(algorithm[, options])</code></a></li> 259<li><a href="#crypto_crypto_diffiehellman_options"><code>crypto.diffieHellman(options)</code></a></li> 260<li><a href="#crypto_crypto_generatekeypair_type_options_callback"><code>crypto.generateKeyPair(type, options, callback)</code></a></li> 261<li><a href="#crypto_crypto_generatekeypairsync_type_options"><code>crypto.generateKeyPairSync(type, options)</code></a></li> 262<li><a href="#crypto_crypto_getciphers"><code>crypto.getCiphers()</code></a></li> 263<li><a href="#crypto_crypto_getcurves"><code>crypto.getCurves()</code></a></li> 264<li><a href="#crypto_crypto_getdiffiehellman_groupname"><code>crypto.getDiffieHellman(groupName)</code></a></li> 265<li><a href="#crypto_crypto_getfips"><code>crypto.getFips()</code></a></li> 266<li><a href="#crypto_crypto_gethashes"><code>crypto.getHashes()</code></a></li> 267<li><a href="#crypto_crypto_pbkdf2_password_salt_iterations_keylen_digest_callback"><code>crypto.pbkdf2(password, salt, iterations, keylen, digest, callback)</code></a></li> 268<li><a href="#crypto_crypto_pbkdf2sync_password_salt_iterations_keylen_digest"><code>crypto.pbkdf2Sync(password, salt, iterations, keylen, digest)</code></a></li> 269<li><a href="#crypto_crypto_privatedecrypt_privatekey_buffer"><code>crypto.privateDecrypt(privateKey, buffer)</code></a></li> 270<li><a href="#crypto_crypto_privateencrypt_privatekey_buffer"><code>crypto.privateEncrypt(privateKey, buffer)</code></a></li> 271<li><a href="#crypto_crypto_publicdecrypt_key_buffer"><code>crypto.publicDecrypt(key, buffer)</code></a></li> 272<li><a href="#crypto_crypto_publicencrypt_key_buffer"><code>crypto.publicEncrypt(key, buffer)</code></a></li> 273<li><a href="#crypto_crypto_randombytes_size_callback"><code>crypto.randomBytes(size[, callback])</code></a></li> 274<li><a href="#crypto_crypto_randomfillsync_buffer_offset_size"><code>crypto.randomFillSync(buffer[, offset][, size])</code></a></li> 275<li><a href="#crypto_crypto_randomfill_buffer_offset_size_callback"><code>crypto.randomFill(buffer[, offset][, size], callback)</code></a></li> 276<li><a href="#crypto_crypto_randomint_min_max_callback"><code>crypto.randomInt([min, ]max[, callback])</code></a></li> 277<li><a href="#crypto_crypto_randomuuid_options"><code>crypto.randomUUID([options])</code></a></li> 278<li><a href="#crypto_crypto_scrypt_password_salt_keylen_options_callback"><code>crypto.scrypt(password, salt, keylen[, options], callback)</code></a></li> 279<li><a href="#crypto_crypto_scryptsync_password_salt_keylen_options"><code>crypto.scryptSync(password, salt, keylen[, options])</code></a></li> 280<li><a href="#crypto_crypto_setengine_engine_flags"><code>crypto.setEngine(engine[, flags])</code></a></li> 281<li><a href="#crypto_crypto_setfips_bool"><code>crypto.setFips(bool)</code></a></li> 282<li><a href="#crypto_crypto_sign_algorithm_data_key"><code>crypto.sign(algorithm, data, key)</code></a></li> 283<li><a href="#crypto_crypto_timingsafeequal_a_b"><code>crypto.timingSafeEqual(a, b)</code></a></li> 284<li><a href="#crypto_crypto_verify_algorithm_data_key_signature"><code>crypto.verify(algorithm, data, key, signature)</code></a></li> 285</ul> 286</li> 287<li><a href="#crypto_notes">Notes</a> 288<ul> 289<li><a href="#crypto_legacy_streams_api_prior_to_node_js_0_10">Legacy streams API (prior to Node.js 0.10)</a></li> 290<li><a href="#crypto_recent_ecdh_changes">Recent ECDH changes</a></li> 291<li><a href="#crypto_support_for_weak_or_compromised_algorithms">Support for weak or compromised algorithms</a></li> 292<li><a href="#crypto_ccm_mode">CCM mode</a></li> 293</ul> 294</li> 295<li><a href="#crypto_crypto_constants_1">Crypto constants</a> 296<ul> 297<li><a href="#crypto_openssl_options">OpenSSL options</a></li> 298<li><a href="#crypto_openssl_engine_constants">OpenSSL engine constants</a></li> 299<li><a href="#crypto_other_openssl_constants">Other OpenSSL constants</a></li> 300<li><a href="#crypto_node_js_crypto_constants">Node.js crypto constants</a></li> 301</ul> 302</li> 303</ul> 304</li> 305</ul></details> 306 307 <div id="apicontent"> 308 <h2>Crypto<span><a class="mark" href="#crypto_crypto" id="crypto_crypto">#</a></span></h2> 309 310<p></p><div class="api_stability api_stability_2"><a href="documentation.html#documentation_stability_index">Stability: 2</a> - Stable</div><p></p> 311<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v14.20.1/lib/crypto.js">lib/crypto.js</a></p> 312<p>The <code>crypto</code> module provides cryptographic functionality that includes a set of 313wrappers for OpenSSL's hash, HMAC, cipher, decipher, sign, and verify functions.</p> 314<p>Use <code>require('crypto')</code> to access this module.</p> 315<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 316 317<span class="hljs-keyword">const</span> secret = <span class="hljs-string">'abcdefg'</span>; 318<span class="hljs-keyword">const</span> hash = crypto.<span class="hljs-title function_">createHmac</span>(<span class="hljs-string">'sha256'</span>, secret) 319 .<span class="hljs-title function_">update</span>(<span class="hljs-string">'I love cupcakes'</span>) 320 .<span class="hljs-title function_">digest</span>(<span class="hljs-string">'hex'</span>); 321<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(hash); 322<span class="hljs-comment">// Prints:</span> 323<span class="hljs-comment">// c0fa1bc00531bd78ef38c628449c5102aeabd49b5dc3a2a516ea6ea959d6658e</span></code></pre> 324<section><h3>Determining if crypto support is unavailable<span><a class="mark" href="#crypto_determining_if_crypto_support_is_unavailable" id="crypto_determining_if_crypto_support_is_unavailable">#</a></span></h3> 325<p>It is possible for Node.js to be built without including support for the 326<code>crypto</code> module. In such cases, calling <code>require('crypto')</code> will result in an 327error being thrown.</p> 328<pre><code class="language-js"><span class="hljs-keyword">let</span> crypto; 329<span class="hljs-keyword">try</span> { 330 crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 331} <span class="hljs-keyword">catch</span> (err) { 332 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'crypto support is disabled!'</span>); 333}</code></pre> 334</section><section><h3>Class: <code>Certificate</code><span><a class="mark" href="#crypto_class_certificate" id="crypto_class_certificate">#</a></span></h3> 335<div class="api_metadata"> 336<span>Added in: v0.11.8</span> 337</div> 338<p>SPKAC is a Certificate Signing Request mechanism originally implemented by 339Netscape and was specified formally as part of <a href="https://developer.mozilla.org/en-US/docs/Web/HTML/Element/keygen">HTML5's <code>keygen</code> element</a>.</p> 340<p><code><keygen></code> is deprecated since <a href="https://www.w3.org/TR/html52/changes.html#features-removed">HTML 5.2</a> and new projects 341should not use this element anymore.</p> 342<p>The <code>crypto</code> module provides the <code>Certificate</code> class for working with SPKAC 343data. The most common usage is handling output generated by the HTML5 344<code><keygen></code> element. Node.js uses <a href="https://www.openssl.org/docs/man1.1.0/apps/openssl-spkac.html">OpenSSL's SPKAC implementation</a> internally.</p> 345<h4><code>Certificate.exportChallenge(spkac)</code><span><a class="mark" href="#crypto_certificate_exportchallenge_spkac" id="crypto_certificate_exportchallenge_spkac">#</a></span></h4> 346<div class="api_metadata"> 347<span>Added in: v9.0.0</span> 348</div> 349<ul> 350<li><code>spkac</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 351<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The challenge component of the <code>spkac</code> data structure, which 352includes a public key and a challenge.</li> 353</ul> 354<pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">Certificate</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 355<span class="hljs-keyword">const</span> spkac = <span class="hljs-title function_">getSpkacSomehow</span>(); 356<span class="hljs-keyword">const</span> challenge = <span class="hljs-title class_">Certificate</span>.<span class="hljs-title function_">exportChallenge</span>(spkac); 357<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(challenge.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'utf8'</span>)); 358<span class="hljs-comment">// Prints: the challenge as a UTF8 string</span></code></pre> 359<h4><code>Certificate.exportPublicKey(spkac[, encoding])</code><span><a class="mark" href="#crypto_certificate_exportpublickey_spkac_encoding" id="crypto_certificate_exportpublickey_spkac_encoding">#</a></span></h4> 360<div class="api_metadata"> 361<span>Added in: v9.0.0</span> 362</div> 363<ul> 364<li><code>spkac</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 365<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>spkac</code> string.</li> 366<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The public key component of the <code>spkac</code> data structure, 367which includes a public key and a challenge.</li> 368</ul> 369<pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">Certificate</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 370<span class="hljs-keyword">const</span> spkac = <span class="hljs-title function_">getSpkacSomehow</span>(); 371<span class="hljs-keyword">const</span> publicKey = <span class="hljs-title class_">Certificate</span>.<span class="hljs-title function_">exportPublicKey</span>(spkac); 372<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(publicKey); 373<span class="hljs-comment">// Prints: the public key as <Buffer ...></span></code></pre> 374<h4><code>Certificate.verifySpkac(spkac)</code><span><a class="mark" href="#crypto_certificate_verifyspkac_spkac" id="crypto_certificate_verifyspkac_spkac">#</a></span></h4> 375<div class="api_metadata"> 376<span>Added in: v9.0.0</span> 377</div> 378<ul> 379<li><code>spkac</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 380<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> if the given <code>spkac</code> data structure is valid, 381<code>false</code> otherwise.</li> 382</ul> 383<pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">Certificate</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 384<span class="hljs-keyword">const</span> spkac = <span class="hljs-title function_">getSpkacSomehow</span>(); 385<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Certificate</span>.<span class="hljs-title function_">verifySpkac</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(spkac))); 386<span class="hljs-comment">// Prints: true or false</span></code></pre> 387<h4>Legacy API<span><a class="mark" href="#crypto_legacy_api" id="crypto_legacy_api">#</a></span></h4> 388<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated</div><p></p> 389<p>As a legacy interface, it is possible to create new instances of 390the <code>crypto.Certificate</code> class as illustrated in the examples below.</p> 391<h5><code>new crypto.Certificate()</code><span><a class="mark" href="#crypto_new_crypto_certificate" id="crypto_new_crypto_certificate">#</a></span></h5> 392<p>Instances of the <code>Certificate</code> class can be created using the <code>new</code> keyword 393or by calling <code>crypto.Certificate()</code> as a function:</p> 394<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 395 396<span class="hljs-keyword">const</span> cert1 = <span class="hljs-keyword">new</span> crypto.<span class="hljs-title class_">Certificate</span>(); 397<span class="hljs-keyword">const</span> cert2 = crypto.<span class="hljs-title class_">Certificate</span>();</code></pre> 398<h5><code>certificate.exportChallenge(spkac)</code><span><a class="mark" href="#crypto_certificate_exportchallenge_spkac_1" id="crypto_certificate_exportchallenge_spkac_1">#</a></span></h5> 399<div class="api_metadata"> 400<span>Added in: v0.11.8</span> 401</div> 402<ul> 403<li><code>spkac</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 404<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The challenge component of the <code>spkac</code> data structure, which 405includes a public key and a challenge.</li> 406</ul> 407<pre><code class="language-js"><span class="hljs-keyword">const</span> cert = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>).<span class="hljs-title class_">Certificate</span>(); 408<span class="hljs-keyword">const</span> spkac = <span class="hljs-title function_">getSpkacSomehow</span>(); 409<span class="hljs-keyword">const</span> challenge = cert.<span class="hljs-title function_">exportChallenge</span>(spkac); 410<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(challenge.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'utf8'</span>)); 411<span class="hljs-comment">// Prints: the challenge as a UTF8 string</span></code></pre> 412<h5><code>certificate.exportPublicKey(spkac)</code><span><a class="mark" href="#crypto_certificate_exportpublickey_spkac" id="crypto_certificate_exportpublickey_spkac">#</a></span></h5> 413<div class="api_metadata"> 414<span>Added in: v0.11.8</span> 415</div> 416<ul> 417<li><code>spkac</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 418<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The public key component of the <code>spkac</code> data structure, 419which includes a public key and a challenge.</li> 420</ul> 421<pre><code class="language-js"><span class="hljs-keyword">const</span> cert = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>).<span class="hljs-title class_">Certificate</span>(); 422<span class="hljs-keyword">const</span> spkac = <span class="hljs-title function_">getSpkacSomehow</span>(); 423<span class="hljs-keyword">const</span> publicKey = cert.<span class="hljs-title function_">exportPublicKey</span>(spkac); 424<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(publicKey); 425<span class="hljs-comment">// Prints: the public key as <Buffer ...></span></code></pre> 426<h5><code>certificate.verifySpkac(spkac)</code><span><a class="mark" href="#crypto_certificate_verifyspkac_spkac_1" id="crypto_certificate_verifyspkac_spkac_1">#</a></span></h5> 427<div class="api_metadata"> 428<span>Added in: v0.11.8</span> 429</div> 430<ul> 431<li><code>spkac</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 432<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> if the given <code>spkac</code> data structure is valid, 433<code>false</code> otherwise.</li> 434</ul> 435<pre><code class="language-js"><span class="hljs-keyword">const</span> cert = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>).<span class="hljs-title class_">Certificate</span>(); 436<span class="hljs-keyword">const</span> spkac = <span class="hljs-title function_">getSpkacSomehow</span>(); 437<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(cert.<span class="hljs-title function_">verifySpkac</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(spkac))); 438<span class="hljs-comment">// Prints: true or false</span></code></pre> 439</section><section><h3>Class: <code>Cipher</code><span><a class="mark" href="#crypto_class_cipher" id="crypto_class_cipher">#</a></span></h3> 440<div class="api_metadata"> 441<span>Added in: v0.1.94</span> 442</div> 443<ul> 444<li>Extends: <a href="stream.html#stream_class_stream_transform" class="type"><stream.Transform></a></li> 445</ul> 446<p>Instances of the <code>Cipher</code> class are used to encrypt data. The class can be 447used in one of two ways:</p> 448<ul> 449<li>As a <a href="stream.html">stream</a> that is both readable and writable, where plain unencrypted 450data is written to produce encrypted data on the readable side, or</li> 451<li>Using the <a href="#crypto_cipher_update_data_inputencoding_outputencoding"><code>cipher.update()</code></a> and <a href="#crypto_cipher_final_outputencoding"><code>cipher.final()</code></a> methods to produce 452the encrypted data.</li> 453</ul> 454<p>The <a href="#crypto_crypto_createcipher_algorithm_password_options"><code>crypto.createCipher()</code></a> or <a href="#crypto_crypto_createcipheriv_algorithm_key_iv_options"><code>crypto.createCipheriv()</code></a> methods are 455used to create <code>Cipher</code> instances. <code>Cipher</code> objects are not to be created 456directly using the <code>new</code> keyword.</p> 457<p>Example: Using <code>Cipher</code> objects as streams:</p> 458<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 459 460<span class="hljs-keyword">const</span> algorithm = <span class="hljs-string">'aes-192-cbc'</span>; 461<span class="hljs-keyword">const</span> password = <span class="hljs-string">'Password used to generate key'</span>; 462<span class="hljs-comment">// Key length is dependent on the algorithm. In this case for aes192, it is</span> 463<span class="hljs-comment">// 24 bytes (192 bits).</span> 464<span class="hljs-comment">// Use async `crypto.scrypt()` instead.</span> 465<span class="hljs-keyword">const</span> key = crypto.<span class="hljs-title function_">scryptSync</span>(password, <span class="hljs-string">'salt'</span>, <span class="hljs-number">24</span>); 466<span class="hljs-comment">// Use `crypto.randomBytes()` to generate a random iv instead of the static iv</span> 467<span class="hljs-comment">// shown here.</span> 468<span class="hljs-keyword">const</span> iv = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">16</span>, <span class="hljs-number">0</span>); <span class="hljs-comment">// Initialization vector.</span> 469 470<span class="hljs-keyword">const</span> cipher = crypto.<span class="hljs-title function_">createCipheriv</span>(algorithm, key, iv); 471 472<span class="hljs-keyword">let</span> encrypted = <span class="hljs-string">''</span>; 473cipher.<span class="hljs-title function_">on</span>(<span class="hljs-string">'readable'</span>, <span class="hljs-function">() =></span> { 474 <span class="hljs-keyword">let</span> chunk; 475 <span class="hljs-keyword">while</span> (<span class="hljs-literal">null</span> !== (chunk = cipher.<span class="hljs-title function_">read</span>())) { 476 encrypted += chunk.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>); 477 } 478}); 479cipher.<span class="hljs-title function_">on</span>(<span class="hljs-string">'end'</span>, <span class="hljs-function">() =></span> { 480 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(encrypted); 481 <span class="hljs-comment">// Prints: e5f79c5915c02171eec6b212d5520d44480993d7d622a7c4c2da32f6efda0ffa</span> 482}); 483 484cipher.<span class="hljs-title function_">write</span>(<span class="hljs-string">'some clear text data'</span>); 485cipher.<span class="hljs-title function_">end</span>();</code></pre> 486<p>Example: Using <code>Cipher</code> and piped streams:</p> 487<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 488<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 489 490<span class="hljs-keyword">const</span> algorithm = <span class="hljs-string">'aes-192-cbc'</span>; 491<span class="hljs-keyword">const</span> password = <span class="hljs-string">'Password used to generate key'</span>; 492<span class="hljs-comment">// Use the async `crypto.scrypt()` instead.</span> 493<span class="hljs-keyword">const</span> key = crypto.<span class="hljs-title function_">scryptSync</span>(password, <span class="hljs-string">'salt'</span>, <span class="hljs-number">24</span>); 494<span class="hljs-comment">// Use `crypto.randomBytes()` to generate a random iv instead of the static iv</span> 495<span class="hljs-comment">// shown here.</span> 496<span class="hljs-keyword">const</span> iv = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">16</span>, <span class="hljs-number">0</span>); <span class="hljs-comment">// Initialization vector.</span> 497 498<span class="hljs-keyword">const</span> cipher = crypto.<span class="hljs-title function_">createCipheriv</span>(algorithm, key, iv); 499 500<span class="hljs-keyword">const</span> input = fs.<span class="hljs-title function_">createReadStream</span>(<span class="hljs-string">'test.js'</span>); 501<span class="hljs-keyword">const</span> output = fs.<span class="hljs-title function_">createWriteStream</span>(<span class="hljs-string">'test.enc'</span>); 502 503input.<span class="hljs-title function_">pipe</span>(cipher).<span class="hljs-title function_">pipe</span>(output);</code></pre> 504<p>Example: Using the <a href="#crypto_cipher_update_data_inputencoding_outputencoding"><code>cipher.update()</code></a> and <a href="#crypto_cipher_final_outputencoding"><code>cipher.final()</code></a> methods:</p> 505<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 506 507<span class="hljs-keyword">const</span> algorithm = <span class="hljs-string">'aes-192-cbc'</span>; 508<span class="hljs-keyword">const</span> password = <span class="hljs-string">'Password used to generate key'</span>; 509<span class="hljs-comment">// Use the async `crypto.scrypt()` instead.</span> 510<span class="hljs-keyword">const</span> key = crypto.<span class="hljs-title function_">scryptSync</span>(password, <span class="hljs-string">'salt'</span>, <span class="hljs-number">24</span>); 511<span class="hljs-comment">// Use `crypto.randomBytes` to generate a random iv instead of the static iv</span> 512<span class="hljs-comment">// shown here.</span> 513<span class="hljs-keyword">const</span> iv = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">16</span>, <span class="hljs-number">0</span>); <span class="hljs-comment">// Initialization vector.</span> 514 515<span class="hljs-keyword">const</span> cipher = crypto.<span class="hljs-title function_">createCipheriv</span>(algorithm, key, iv); 516 517<span class="hljs-keyword">let</span> encrypted = cipher.<span class="hljs-title function_">update</span>(<span class="hljs-string">'some clear text data'</span>, <span class="hljs-string">'utf8'</span>, <span class="hljs-string">'hex'</span>); 518encrypted += cipher.<span class="hljs-title function_">final</span>(<span class="hljs-string">'hex'</span>); 519<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(encrypted); 520<span class="hljs-comment">// Prints: e5f79c5915c02171eec6b212d5520d44480993d7d622a7c4c2da32f6efda0ffa</span></code></pre> 521<h4><code>cipher.final([outputEncoding])</code><span><a class="mark" href="#crypto_cipher_final_outputencoding" id="crypto_cipher_final_outputencoding">#</a></span></h4> 522<div class="api_metadata"> 523<span>Added in: v0.1.94</span> 524</div> 525<ul> 526<li><code>outputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 527<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Any remaining enciphered contents. 528If <code>outputEncoding</code> is specified, a string is 529returned. If an <code>outputEncoding</code> is not provided, a <a href="buffer.html"><code>Buffer</code></a> is returned.</li> 530</ul> 531<p>Once the <code>cipher.final()</code> method has been called, the <code>Cipher</code> object can no 532longer be used to encrypt data. Attempts to call <code>cipher.final()</code> more than 533once will result in an error being thrown.</p> 534<h4><code>cipher.getAuthTag()</code><span><a class="mark" href="#crypto_cipher_getauthtag" id="crypto_cipher_getauthtag">#</a></span></h4> 535<div class="api_metadata"> 536<span>Added in: v1.0.0</span> 537</div> 538<ul> 539<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> When using an authenticated encryption mode (<code>GCM</code>, <code>CCM</code> 540and <code>OCB</code> are currently supported), the <code>cipher.getAuthTag()</code> method returns a 541<a href="buffer.html"><code>Buffer</code></a> containing the <em>authentication tag</em> that has been computed from 542the given data.</li> 543</ul> 544<p>The <code>cipher.getAuthTag()</code> method should only be called after encryption has 545been completed using the <a href="#crypto_cipher_final_outputencoding"><code>cipher.final()</code></a> method.</p> 546<h4><code>cipher.setAAD(buffer[, options])</code><span><a class="mark" href="#crypto_cipher_setaad_buffer_options" id="crypto_cipher_setaad_buffer_options">#</a></span></h4> 547<div class="api_metadata"> 548<span>Added in: v1.0.0</span> 549</div> 550<ul> 551<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 552<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a> 553<ul> 554<li><code>plaintextLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 555</ul> 556</li> 557<li>Returns: <a href="crypto.html#crypto_class_cipher" class="type"><Cipher></a> for method chaining.</li> 558</ul> 559<p>When using an authenticated encryption mode (<code>GCM</code>, <code>CCM</code> and <code>OCB</code> are 560currently supported), the <code>cipher.setAAD()</code> method sets the value used for the 561<em>additional authenticated data</em> (AAD) input parameter.</p> 562<p>The <code>options</code> argument is optional for <code>GCM</code> and <code>OCB</code>. When using <code>CCM</code>, the 563<code>plaintextLength</code> option must be specified and its value must match the length 564of the plaintext in bytes. See <a href="#crypto_ccm_mode">CCM mode</a>.</p> 565<p>The <code>cipher.setAAD()</code> method must be called before <a href="#crypto_cipher_update_data_inputencoding_outputencoding"><code>cipher.update()</code></a>.</p> 566<h4><code>cipher.setAutoPadding([autoPadding])</code><span><a class="mark" href="#crypto_cipher_setautopadding_autopadding" id="crypto_cipher_setautopadding_autopadding">#</a></span></h4> 567<div class="api_metadata"> 568<span>Added in: v0.7.1</span> 569</div> 570<ul> 571<li><code>autoPadding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <strong>Default:</strong> <code>true</code></li> 572<li>Returns: <a href="crypto.html#crypto_class_cipher" class="type"><Cipher></a> for method chaining.</li> 573</ul> 574<p>When using block encryption algorithms, the <code>Cipher</code> class will automatically 575add padding to the input data to the appropriate block size. To disable the 576default padding call <code>cipher.setAutoPadding(false)</code>.</p> 577<p>When <code>autoPadding</code> is <code>false</code>, the length of the entire input data must be a 578multiple of the cipher's block size or <a href="#crypto_cipher_final_outputencoding"><code>cipher.final()</code></a> will throw an error. 579Disabling automatic padding is useful for non-standard padding, for instance 580using <code>0x0</code> instead of PKCS padding.</p> 581<p>The <code>cipher.setAutoPadding()</code> method must be called before 582<a href="#crypto_cipher_final_outputencoding"><code>cipher.final()</code></a>.</p> 583<h4><code>cipher.update(data[, inputEncoding][, outputEncoding])</code><span><a class="mark" href="#crypto_cipher_update_data_inputencoding_outputencoding" id="crypto_cipher_update_data_inputencoding_outputencoding">#</a></span></h4> 584<div class="api_metadata"> 585<details class="changelog"><summary>History</summary> 586<table> 587<tbody><tr><th>Version</th><th>Changes</th></tr> 588<tr><td>v6.0.0</td> 589<td><p>The default <code>inputEncoding</code> changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 590<tr><td>v0.1.94</td> 591<td><p><span>Added in: v0.1.94</span></p></td></tr> 592</tbody></table> 593</details> 594</div> 595<ul> 596<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 597<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the data.</li> 598<li><code>outputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 599<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 600</ul> 601<p>Updates the cipher with <code>data</code>. If the <code>inputEncoding</code> argument is given, 602the <code>data</code> 603argument is a string using the specified encoding. If the <code>inputEncoding</code> 604argument is not given, <code>data</code> must be a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or 605<code>DataView</code>. If <code>data</code> is a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or <code>DataView</code>, then 606<code>inputEncoding</code> is ignored.</p> 607<p>The <code>outputEncoding</code> specifies the output format of the enciphered 608data. If the <code>outputEncoding</code> 609is specified, a string using the specified encoding is returned. If no 610<code>outputEncoding</code> is provided, a <a href="buffer.html"><code>Buffer</code></a> is returned.</p> 611<p>The <code>cipher.update()</code> method can be called multiple times with new data until 612<a href="#crypto_cipher_final_outputencoding"><code>cipher.final()</code></a> is called. Calling <code>cipher.update()</code> after 613<a href="#crypto_cipher_final_outputencoding"><code>cipher.final()</code></a> will result in an error being thrown.</p> 614</section><section><h3>Class: <code>Decipher</code><span><a class="mark" href="#crypto_class_decipher" id="crypto_class_decipher">#</a></span></h3> 615<div class="api_metadata"> 616<span>Added in: v0.1.94</span> 617</div> 618<ul> 619<li>Extends: <a href="stream.html#stream_class_stream_transform" class="type"><stream.Transform></a></li> 620</ul> 621<p>Instances of the <code>Decipher</code> class are used to decrypt data. The class can be 622used in one of two ways:</p> 623<ul> 624<li>As a <a href="stream.html">stream</a> that is both readable and writable, where plain encrypted 625data is written to produce unencrypted data on the readable side, or</li> 626<li>Using the <a href="#crypto_decipher_update_data_inputencoding_outputencoding"><code>decipher.update()</code></a> and <a href="#crypto_decipher_final_outputencoding"><code>decipher.final()</code></a> methods to 627produce the unencrypted data.</li> 628</ul> 629<p>The <a href="#crypto_crypto_createdecipher_algorithm_password_options"><code>crypto.createDecipher()</code></a> or <a href="#crypto_crypto_createdecipheriv_algorithm_key_iv_options"><code>crypto.createDecipheriv()</code></a> methods are 630used to create <code>Decipher</code> instances. <code>Decipher</code> objects are not to be created 631directly using the <code>new</code> keyword.</p> 632<p>Example: Using <code>Decipher</code> objects as streams:</p> 633<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 634 635<span class="hljs-keyword">const</span> algorithm = <span class="hljs-string">'aes-192-cbc'</span>; 636<span class="hljs-keyword">const</span> password = <span class="hljs-string">'Password used to generate key'</span>; 637<span class="hljs-comment">// Key length is dependent on the algorithm. In this case for aes192, it is</span> 638<span class="hljs-comment">// 24 bytes (192 bits).</span> 639<span class="hljs-comment">// Use the async `crypto.scrypt()` instead.</span> 640<span class="hljs-keyword">const</span> key = crypto.<span class="hljs-title function_">scryptSync</span>(password, <span class="hljs-string">'salt'</span>, <span class="hljs-number">24</span>); 641<span class="hljs-comment">// The IV is usually passed along with the ciphertext.</span> 642<span class="hljs-keyword">const</span> iv = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">16</span>, <span class="hljs-number">0</span>); <span class="hljs-comment">// Initialization vector.</span> 643 644<span class="hljs-keyword">const</span> decipher = crypto.<span class="hljs-title function_">createDecipheriv</span>(algorithm, key, iv); 645 646<span class="hljs-keyword">let</span> decrypted = <span class="hljs-string">''</span>; 647decipher.<span class="hljs-title function_">on</span>(<span class="hljs-string">'readable'</span>, <span class="hljs-function">() =></span> { 648 <span class="hljs-keyword">while</span> (<span class="hljs-literal">null</span> !== (chunk = decipher.<span class="hljs-title function_">read</span>())) { 649 decrypted += chunk.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'utf8'</span>); 650 } 651}); 652decipher.<span class="hljs-title function_">on</span>(<span class="hljs-string">'end'</span>, <span class="hljs-function">() =></span> { 653 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(decrypted); 654 <span class="hljs-comment">// Prints: some clear text data</span> 655}); 656 657<span class="hljs-comment">// Encrypted with same algorithm, key and iv.</span> 658<span class="hljs-keyword">const</span> encrypted = 659 <span class="hljs-string">'e5f79c5915c02171eec6b212d5520d44480993d7d622a7c4c2da32f6efda0ffa'</span>; 660decipher.<span class="hljs-title function_">write</span>(encrypted, <span class="hljs-string">'hex'</span>); 661decipher.<span class="hljs-title function_">end</span>();</code></pre> 662<p>Example: Using <code>Decipher</code> and piped streams:</p> 663<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 664<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 665 666<span class="hljs-keyword">const</span> algorithm = <span class="hljs-string">'aes-192-cbc'</span>; 667<span class="hljs-keyword">const</span> password = <span class="hljs-string">'Password used to generate key'</span>; 668<span class="hljs-comment">// Use the async `crypto.scrypt()` instead.</span> 669<span class="hljs-keyword">const</span> key = crypto.<span class="hljs-title function_">scryptSync</span>(password, <span class="hljs-string">'salt'</span>, <span class="hljs-number">24</span>); 670<span class="hljs-comment">// The IV is usually passed along with the ciphertext.</span> 671<span class="hljs-keyword">const</span> iv = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">16</span>, <span class="hljs-number">0</span>); <span class="hljs-comment">// Initialization vector.</span> 672 673<span class="hljs-keyword">const</span> decipher = crypto.<span class="hljs-title function_">createDecipheriv</span>(algorithm, key, iv); 674 675<span class="hljs-keyword">const</span> input = fs.<span class="hljs-title function_">createReadStream</span>(<span class="hljs-string">'test.enc'</span>); 676<span class="hljs-keyword">const</span> output = fs.<span class="hljs-title function_">createWriteStream</span>(<span class="hljs-string">'test.js'</span>); 677 678input.<span class="hljs-title function_">pipe</span>(decipher).<span class="hljs-title function_">pipe</span>(output);</code></pre> 679<p>Example: Using the <a href="#crypto_decipher_update_data_inputencoding_outputencoding"><code>decipher.update()</code></a> and <a href="#crypto_decipher_final_outputencoding"><code>decipher.final()</code></a> methods:</p> 680<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 681 682<span class="hljs-keyword">const</span> algorithm = <span class="hljs-string">'aes-192-cbc'</span>; 683<span class="hljs-keyword">const</span> password = <span class="hljs-string">'Password used to generate key'</span>; 684<span class="hljs-comment">// Use the async `crypto.scrypt()` instead.</span> 685<span class="hljs-keyword">const</span> key = crypto.<span class="hljs-title function_">scryptSync</span>(password, <span class="hljs-string">'salt'</span>, <span class="hljs-number">24</span>); 686<span class="hljs-comment">// The IV is usually passed along with the ciphertext.</span> 687<span class="hljs-keyword">const</span> iv = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">16</span>, <span class="hljs-number">0</span>); <span class="hljs-comment">// Initialization vector.</span> 688 689<span class="hljs-keyword">const</span> decipher = crypto.<span class="hljs-title function_">createDecipheriv</span>(algorithm, key, iv); 690 691<span class="hljs-comment">// Encrypted using same algorithm, key and iv.</span> 692<span class="hljs-keyword">const</span> encrypted = 693 <span class="hljs-string">'e5f79c5915c02171eec6b212d5520d44480993d7d622a7c4c2da32f6efda0ffa'</span>; 694<span class="hljs-keyword">let</span> decrypted = decipher.<span class="hljs-title function_">update</span>(encrypted, <span class="hljs-string">'hex'</span>, <span class="hljs-string">'utf8'</span>); 695decrypted += decipher.<span class="hljs-title function_">final</span>(<span class="hljs-string">'utf8'</span>); 696<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(decrypted); 697<span class="hljs-comment">// Prints: some clear text data</span></code></pre> 698<h4><code>decipher.final([outputEncoding])</code><span><a class="mark" href="#crypto_decipher_final_outputencoding" id="crypto_decipher_final_outputencoding">#</a></span></h4> 699<div class="api_metadata"> 700<span>Added in: v0.1.94</span> 701</div> 702<ul> 703<li><code>outputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 704<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Any remaining deciphered contents. 705If <code>outputEncoding</code> is specified, a string is 706returned. If an <code>outputEncoding</code> is not provided, a <a href="buffer.html"><code>Buffer</code></a> is returned.</li> 707</ul> 708<p>Once the <code>decipher.final()</code> method has been called, the <code>Decipher</code> object can 709no longer be used to decrypt data. Attempts to call <code>decipher.final()</code> more 710than once will result in an error being thrown.</p> 711<h4><code>decipher.setAAD(buffer[, options])</code><span><a class="mark" href="#crypto_decipher_setaad_buffer_options" id="crypto_decipher_setaad_buffer_options">#</a></span></h4> 712<div class="api_metadata"> 713<details class="changelog"><summary>History</summary> 714<table> 715<tbody><tr><th>Version</th><th>Changes</th></tr> 716<tr><td>v7.2.0</td> 717<td><p>This method now returns a reference to <code>decipher</code>.</p></td></tr> 718<tr><td>v1.0.0</td> 719<td><p><span>Added in: v1.0.0</span></p></td></tr> 720</tbody></table> 721</details> 722</div> 723<ul> 724<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 725<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a> 726<ul> 727<li><code>plaintextLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 728</ul> 729</li> 730<li>Returns: <a href="crypto.html#crypto_class_decipher" class="type"><Decipher></a> for method chaining.</li> 731</ul> 732<p>When using an authenticated encryption mode (<code>GCM</code>, <code>CCM</code> and <code>OCB</code> are 733currently supported), the <code>decipher.setAAD()</code> method sets the value used for the 734<em>additional authenticated data</em> (AAD) input parameter.</p> 735<p>The <code>options</code> argument is optional for <code>GCM</code>. When using <code>CCM</code>, the 736<code>plaintextLength</code> option must be specified and its value must match the length 737of the ciphertext in bytes. See <a href="#crypto_ccm_mode">CCM mode</a>.</p> 738<p>The <code>decipher.setAAD()</code> method must be called before <a href="#crypto_decipher_update_data_inputencoding_outputencoding"><code>decipher.update()</code></a>.</p> 739<h4><code>decipher.setAuthTag(buffer)</code><span><a class="mark" href="#crypto_decipher_setauthtag_buffer" id="crypto_decipher_setauthtag_buffer">#</a></span></h4> 740<div class="api_metadata"> 741<details class="changelog"><summary>History</summary> 742<table> 743<tbody><tr><th>Version</th><th>Changes</th></tr> 744<tr><td>v11.0.0</td> 745<td><p>This method now throws if the GCM tag length is invalid.</p></td></tr> 746<tr><td>v7.2.0</td> 747<td><p>This method now returns a reference to <code>decipher</code>.</p></td></tr> 748<tr><td>v1.0.0</td> 749<td><p><span>Added in: v1.0.0</span></p></td></tr> 750</tbody></table> 751</details> 752</div> 753<ul> 754<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 755<li>Returns: <a href="crypto.html#crypto_class_decipher" class="type"><Decipher></a> for method chaining.</li> 756</ul> 757<p>When using an authenticated encryption mode (<code>GCM</code>, <code>CCM</code> and <code>OCB</code> are 758currently supported), the <code>decipher.setAuthTag()</code> method is used to pass in the 759received <em>authentication tag</em>. If no tag is provided, or if the cipher text 760has been tampered with, <a href="#crypto_decipher_final_outputencoding"><code>decipher.final()</code></a> will throw, indicating that the 761cipher text should be discarded due to failed authentication. If the tag length 762is invalid according to <a href="https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf">NIST SP 800-38D</a> or does not match the value of the 763<code>authTagLength</code> option, <code>decipher.setAuthTag()</code> will throw an error.</p> 764<p>The <code>decipher.setAuthTag()</code> method must be called before <a href="#crypto_decipher_update_data_inputencoding_outputencoding"><code>decipher.update()</code></a> 765for <code>CCM</code> mode or before <a href="#crypto_decipher_final_outputencoding"><code>decipher.final()</code></a> for <code>GCM</code> and <code>OCB</code> modes. 766<code>decipher.setAuthTag()</code> can only be called once.</p> 767<h4><code>decipher.setAutoPadding([autoPadding])</code><span><a class="mark" href="#crypto_decipher_setautopadding_autopadding" id="crypto_decipher_setautopadding_autopadding">#</a></span></h4> 768<div class="api_metadata"> 769<span>Added in: v0.7.1</span> 770</div> 771<ul> 772<li><code>autoPadding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <strong>Default:</strong> <code>true</code></li> 773<li>Returns: <a href="crypto.html#crypto_class_decipher" class="type"><Decipher></a> for method chaining.</li> 774</ul> 775<p>When data has been encrypted without standard block padding, calling 776<code>decipher.setAutoPadding(false)</code> will disable automatic padding to prevent 777<a href="#crypto_decipher_final_outputencoding"><code>decipher.final()</code></a> from checking for and removing padding.</p> 778<p>Turning auto padding off will only work if the input data's length is a 779multiple of the ciphers block size.</p> 780<p>The <code>decipher.setAutoPadding()</code> method must be called before 781<a href="#crypto_decipher_final_outputencoding"><code>decipher.final()</code></a>.</p> 782<h4><code>decipher.update(data[, inputEncoding][, outputEncoding])</code><span><a class="mark" href="#crypto_decipher_update_data_inputencoding_outputencoding" id="crypto_decipher_update_data_inputencoding_outputencoding">#</a></span></h4> 783<div class="api_metadata"> 784<details class="changelog"><summary>History</summary> 785<table> 786<tbody><tr><th>Version</th><th>Changes</th></tr> 787<tr><td>v6.0.0</td> 788<td><p>The default <code>inputEncoding</code> changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 789<tr><td>v0.1.94</td> 790<td><p><span>Added in: v0.1.94</span></p></td></tr> 791</tbody></table> 792</details> 793</div> 794<ul> 795<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 796<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>data</code> string.</li> 797<li><code>outputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 798<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 799</ul> 800<p>Updates the decipher with <code>data</code>. If the <code>inputEncoding</code> argument is given, 801the <code>data</code> 802argument is a string using the specified encoding. If the <code>inputEncoding</code> 803argument is not given, <code>data</code> must be a <a href="buffer.html"><code>Buffer</code></a>. If <code>data</code> is a 804<a href="buffer.html"><code>Buffer</code></a> then <code>inputEncoding</code> is ignored.</p> 805<p>The <code>outputEncoding</code> specifies the output format of the enciphered 806data. If the <code>outputEncoding</code> 807is specified, a string using the specified encoding is returned. If no 808<code>outputEncoding</code> is provided, a <a href="buffer.html"><code>Buffer</code></a> is returned.</p> 809<p>The <code>decipher.update()</code> method can be called multiple times with new data until 810<a href="#crypto_decipher_final_outputencoding"><code>decipher.final()</code></a> is called. Calling <code>decipher.update()</code> after 811<a href="#crypto_decipher_final_outputencoding"><code>decipher.final()</code></a> will result in an error being thrown.</p> 812</section><section><h3>Class: <code>DiffieHellman</code><span><a class="mark" href="#crypto_class_diffiehellman" id="crypto_class_diffiehellman">#</a></span></h3> 813<div class="api_metadata"> 814<span>Added in: v0.5.0</span> 815</div> 816<p>The <code>DiffieHellman</code> class is a utility for creating Diffie-Hellman key 817exchanges.</p> 818<p>Instances of the <code>DiffieHellman</code> class can be created using the 819<a href="#crypto_crypto_creatediffiehellman_prime_primeencoding_generator_generatorencoding"><code>crypto.createDiffieHellman()</code></a> function.</p> 820<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 821<span class="hljs-keyword">const</span> assert = <span class="hljs-built_in">require</span>(<span class="hljs-string">'assert'</span>); 822 823<span class="hljs-comment">// Generate Alice's keys...</span> 824<span class="hljs-keyword">const</span> alice = crypto.<span class="hljs-title function_">createDiffieHellman</span>(<span class="hljs-number">2048</span>); 825<span class="hljs-keyword">const</span> aliceKey = alice.<span class="hljs-title function_">generateKeys</span>(); 826 827<span class="hljs-comment">// Generate Bob's keys...</span> 828<span class="hljs-keyword">const</span> bob = crypto.<span class="hljs-title function_">createDiffieHellman</span>(alice.<span class="hljs-title function_">getPrime</span>(), alice.<span class="hljs-title function_">getGenerator</span>()); 829<span class="hljs-keyword">const</span> bobKey = bob.<span class="hljs-title function_">generateKeys</span>(); 830 831<span class="hljs-comment">// Exchange and generate the secret...</span> 832<span class="hljs-keyword">const</span> aliceSecret = alice.<span class="hljs-title function_">computeSecret</span>(bobKey); 833<span class="hljs-keyword">const</span> bobSecret = bob.<span class="hljs-title function_">computeSecret</span>(aliceKey); 834 835<span class="hljs-comment">// OK</span> 836assert.<span class="hljs-title function_">strictEqual</span>(aliceSecret.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>), bobSecret.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>));</code></pre> 837<h4><code>diffieHellman.computeSecret(otherPublicKey[, inputEncoding][, outputEncoding])</code><span><a class="mark" href="#crypto_diffiehellman_computesecret_otherpublickey_inputencoding_outputencoding" id="crypto_diffiehellman_computesecret_otherpublickey_inputencoding_outputencoding">#</a></span></h4> 838<div class="api_metadata"> 839<span>Added in: v0.5.0</span> 840</div> 841<ul> 842<li><code>otherPublicKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 843<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of an <code>otherPublicKey</code> string.</li> 844<li><code>outputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 845<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 846</ul> 847<p>Computes the shared secret using <code>otherPublicKey</code> as the other 848party's public key and returns the computed shared secret. The supplied 849key is interpreted using the specified <code>inputEncoding</code>, and secret is 850encoded using specified <code>outputEncoding</code>. 851If the <code>inputEncoding</code> is not 852provided, <code>otherPublicKey</code> is expected to be a <a href="buffer.html"><code>Buffer</code></a>, 853<code>TypedArray</code>, or <code>DataView</code>.</p> 854<p>If <code>outputEncoding</code> is given a string is returned; otherwise, a 855<a href="buffer.html"><code>Buffer</code></a> is returned.</p> 856<h4><code>diffieHellman.generateKeys([encoding])</code><span><a class="mark" href="#crypto_diffiehellman_generatekeys_encoding" id="crypto_diffiehellman_generatekeys_encoding">#</a></span></h4> 857<div class="api_metadata"> 858<span>Added in: v0.5.0</span> 859</div> 860<ul> 861<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 862<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 863</ul> 864<p>Generates private and public Diffie-Hellman key values, and returns 865the public key in the specified <code>encoding</code>. This key should be 866transferred to the other party. 867If <code>encoding</code> is provided a string is returned; otherwise a 868<a href="buffer.html"><code>Buffer</code></a> is returned.</p> 869<h4><code>diffieHellman.getGenerator([encoding])</code><span><a class="mark" href="#crypto_diffiehellman_getgenerator_encoding" id="crypto_diffiehellman_getgenerator_encoding">#</a></span></h4> 870<div class="api_metadata"> 871<span>Added in: v0.5.0</span> 872</div> 873<ul> 874<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 875<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 876</ul> 877<p>Returns the Diffie-Hellman generator in the specified <code>encoding</code>. 878If <code>encoding</code> is provided a string is 879returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> is returned.</p> 880<h4><code>diffieHellman.getPrime([encoding])</code><span><a class="mark" href="#crypto_diffiehellman_getprime_encoding" id="crypto_diffiehellman_getprime_encoding">#</a></span></h4> 881<div class="api_metadata"> 882<span>Added in: v0.5.0</span> 883</div> 884<ul> 885<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 886<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 887</ul> 888<p>Returns the Diffie-Hellman prime in the specified <code>encoding</code>. 889If <code>encoding</code> is provided a string is 890returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> is returned.</p> 891<h4><code>diffieHellman.getPrivateKey([encoding])</code><span><a class="mark" href="#crypto_diffiehellman_getprivatekey_encoding" id="crypto_diffiehellman_getprivatekey_encoding">#</a></span></h4> 892<div class="api_metadata"> 893<span>Added in: v0.5.0</span> 894</div> 895<ul> 896<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 897<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 898</ul> 899<p>Returns the Diffie-Hellman private key in the specified <code>encoding</code>. 900If <code>encoding</code> is provided a 901string is returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> is returned.</p> 902<h4><code>diffieHellman.getPublicKey([encoding])</code><span><a class="mark" href="#crypto_diffiehellman_getpublickey_encoding" id="crypto_diffiehellman_getpublickey_encoding">#</a></span></h4> 903<div class="api_metadata"> 904<span>Added in: v0.5.0</span> 905</div> 906<ul> 907<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 908<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 909</ul> 910<p>Returns the Diffie-Hellman public key in the specified <code>encoding</code>. 911If <code>encoding</code> is provided a 912string is returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> is returned.</p> 913<h4><code>diffieHellman.setPrivateKey(privateKey[, encoding])</code><span><a class="mark" href="#crypto_diffiehellman_setprivatekey_privatekey_encoding" id="crypto_diffiehellman_setprivatekey_privatekey_encoding">#</a></span></h4> 914<div class="api_metadata"> 915<span>Added in: v0.5.0</span> 916</div> 917<ul> 918<li><code>privateKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 919<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>privateKey</code> string.</li> 920</ul> 921<p>Sets the Diffie-Hellman private key. If the <code>encoding</code> argument is provided, 922<code>privateKey</code> is expected 923to be a string. If no <code>encoding</code> is provided, <code>privateKey</code> is expected 924to be a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or <code>DataView</code>.</p> 925<h4><code>diffieHellman.setPublicKey(publicKey[, encoding])</code><span><a class="mark" href="#crypto_diffiehellman_setpublickey_publickey_encoding" id="crypto_diffiehellman_setpublickey_publickey_encoding">#</a></span></h4> 926<div class="api_metadata"> 927<span>Added in: v0.5.0</span> 928</div> 929<ul> 930<li><code>publicKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 931<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>publicKey</code> string.</li> 932</ul> 933<p>Sets the Diffie-Hellman public key. If the <code>encoding</code> argument is provided, 934<code>publicKey</code> is expected 935to be a string. If no <code>encoding</code> is provided, <code>publicKey</code> is expected 936to be a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or <code>DataView</code>.</p> 937<h4><code>diffieHellman.verifyError</code><span><a class="mark" href="#crypto_diffiehellman_verifyerror" id="crypto_diffiehellman_verifyerror">#</a></span></h4> 938<div class="api_metadata"> 939<span>Added in: v0.11.12</span> 940</div> 941<p>A bit field containing any warnings and/or errors resulting from a check 942performed during initialization of the <code>DiffieHellman</code> object.</p> 943<p>The following values are valid for this property (as defined in <code>constants</code> 944module):</p> 945<ul> 946<li><code>DH_CHECK_P_NOT_SAFE_PRIME</code></li> 947<li><code>DH_CHECK_P_NOT_PRIME</code></li> 948<li><code>DH_UNABLE_TO_CHECK_GENERATOR</code></li> 949<li><code>DH_NOT_SUITABLE_GENERATOR</code></li> 950</ul> 951</section><section><h3>Class: <code>DiffieHellmanGroup</code><span><a class="mark" href="#crypto_class_diffiehellmangroup" id="crypto_class_diffiehellmangroup">#</a></span></h3> 952<div class="api_metadata"> 953<span>Added in: v0.7.5</span> 954</div> 955<p>The <code>DiffieHellmanGroup</code> class takes a well-known modp group as its argument. 956It works the same as <code>DiffieHellman</code>, except that it does not allow changing 957its keys after creation. In other words, it does not implement <code>setPublicKey()</code> 958or <code>setPrivateKey()</code> methods.</p> 959<pre><code class="language-js"><span class="hljs-keyword">const</span> name = <span class="hljs-string">'modp1'</span>; 960<span class="hljs-keyword">const</span> dh = crypto.<span class="hljs-title function_">createDiffieHellmanGroup</span>(name);</code></pre> 961<p><code>name</code> is taken from <a href="https://www.rfc-editor.org/rfc/rfc2412.txt">RFC 2412</a> (modp1 and 2) and <a href="https://www.rfc-editor.org/rfc/rfc3526.txt">RFC 3526</a>:</p> 962<pre><code class="language-console"><span class="hljs-meta">$ </span><span class="language-bash">perl -ne <span class="hljs-string">'print "$1\n" if /"(modp\d+)"/'</span> src/node_crypto_groups.h</span> 963modp1 # 768 bits 964modp2 # 1024 bits 965modp5 # 1536 bits 966modp14 # 2048 bits 967modp15 # etc. 968modp16 969modp17 970modp18</code></pre> 971</section><section><h3>Class: <code>ECDH</code><span><a class="mark" href="#crypto_class_ecdh" id="crypto_class_ecdh">#</a></span></h3> 972<div class="api_metadata"> 973<span>Added in: v0.11.14</span> 974</div> 975<p>The <code>ECDH</code> class is a utility for creating Elliptic Curve Diffie-Hellman (ECDH) 976key exchanges.</p> 977<p>Instances of the <code>ECDH</code> class can be created using the 978<a href="#crypto_crypto_createecdh_curvename"><code>crypto.createECDH()</code></a> function.</p> 979<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 980<span class="hljs-keyword">const</span> assert = <span class="hljs-built_in">require</span>(<span class="hljs-string">'assert'</span>); 981 982<span class="hljs-comment">// Generate Alice's keys...</span> 983<span class="hljs-keyword">const</span> alice = crypto.<span class="hljs-title function_">createECDH</span>(<span class="hljs-string">'secp521r1'</span>); 984<span class="hljs-keyword">const</span> aliceKey = alice.<span class="hljs-title function_">generateKeys</span>(); 985 986<span class="hljs-comment">// Generate Bob's keys...</span> 987<span class="hljs-keyword">const</span> bob = crypto.<span class="hljs-title function_">createECDH</span>(<span class="hljs-string">'secp521r1'</span>); 988<span class="hljs-keyword">const</span> bobKey = bob.<span class="hljs-title function_">generateKeys</span>(); 989 990<span class="hljs-comment">// Exchange and generate the secret...</span> 991<span class="hljs-keyword">const</span> aliceSecret = alice.<span class="hljs-title function_">computeSecret</span>(bobKey); 992<span class="hljs-keyword">const</span> bobSecret = bob.<span class="hljs-title function_">computeSecret</span>(aliceKey); 993 994assert.<span class="hljs-title function_">strictEqual</span>(aliceSecret.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>), bobSecret.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 995<span class="hljs-comment">// OK</span></code></pre> 996<h4>Static method: <code>ECDH.convertKey(key, curve[, inputEncoding[, outputEncoding[, format]]])</code><span><a class="mark" href="#crypto_static_method_ecdh_convertkey_key_curve_inputencoding_outputencoding_format" id="crypto_static_method_ecdh_convertkey_key_curve_inputencoding_outputencoding_format">#</a></span></h4> 997<div class="api_metadata"> 998<span>Added in: v10.0.0</span> 999</div> 1000<ul> 1001<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1002<li><code>curve</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1003<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>key</code> string.</li> 1004<li><code>outputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 1005<li><code>format</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> <strong>Default:</strong> <code>'uncompressed'</code></li> 1006<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1007</ul> 1008<p>Converts the EC Diffie-Hellman public key specified by <code>key</code> and <code>curve</code> to the 1009format specified by <code>format</code>. The <code>format</code> argument specifies point encoding 1010and can be <code>'compressed'</code>, <code>'uncompressed'</code> or <code>'hybrid'</code>. The supplied key is 1011interpreted using the specified <code>inputEncoding</code>, and the returned key is encoded 1012using the specified <code>outputEncoding</code>.</p> 1013<p>Use <a href="#crypto_crypto_getcurves"><code>crypto.getCurves()</code></a> to obtain a list of available curve names. 1014On recent OpenSSL releases, <code>openssl ecparam -list_curves</code> will also display 1015the name and description of each available elliptic curve.</p> 1016<p>If <code>format</code> is not specified the point will be returned in <code>'uncompressed'</code> 1017format.</p> 1018<p>If the <code>inputEncoding</code> is not provided, <code>key</code> is expected to be a <a href="buffer.html"><code>Buffer</code></a>, 1019<code>TypedArray</code>, or <code>DataView</code>.</p> 1020<p>Example (uncompressing a key):</p> 1021<pre><code class="language-js"><span class="hljs-keyword">const</span> { createECDH, <span class="hljs-variable constant_">ECDH</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1022 1023<span class="hljs-keyword">const</span> ecdh = <span class="hljs-title function_">createECDH</span>(<span class="hljs-string">'secp256k1'</span>); 1024ecdh.<span class="hljs-title function_">generateKeys</span>(); 1025 1026<span class="hljs-keyword">const</span> compressedKey = ecdh.<span class="hljs-title function_">getPublicKey</span>(<span class="hljs-string">'hex'</span>, <span class="hljs-string">'compressed'</span>); 1027 1028<span class="hljs-keyword">const</span> uncompressedKey = <span class="hljs-variable constant_">ECDH</span>.<span class="hljs-title function_">convertKey</span>(compressedKey, 1029 <span class="hljs-string">'secp256k1'</span>, 1030 <span class="hljs-string">'hex'</span>, 1031 <span class="hljs-string">'hex'</span>, 1032 <span class="hljs-string">'uncompressed'</span>); 1033 1034<span class="hljs-comment">// The converted key and the uncompressed public key should be the same</span> 1035<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(uncompressedKey === ecdh.<span class="hljs-title function_">getPublicKey</span>(<span class="hljs-string">'hex'</span>));</code></pre> 1036<h4><code>ecdh.computeSecret(otherPublicKey[, inputEncoding][, outputEncoding])</code><span><a class="mark" href="#crypto_ecdh_computesecret_otherpublickey_inputencoding_outputencoding" id="crypto_ecdh_computesecret_otherpublickey_inputencoding_outputencoding">#</a></span></h4> 1037<div class="api_metadata"> 1038<details class="changelog"><summary>History</summary> 1039<table> 1040<tbody><tr><th>Version</th><th>Changes</th></tr> 1041<tr><td>v10.0.0</td> 1042<td><p>Changed error format to better support invalid public key error.</p></td></tr> 1043<tr><td>v6.0.0</td> 1044<td><p>The default <code>inputEncoding</code> changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 1045<tr><td>v0.11.14</td> 1046<td><p><span>Added in: v0.11.14</span></p></td></tr> 1047</tbody></table> 1048</details> 1049</div> 1050<ul> 1051<li><code>otherPublicKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1052<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>otherPublicKey</code> string.</li> 1053<li><code>outputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 1054<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1055</ul> 1056<p>Computes the shared secret using <code>otherPublicKey</code> as the other 1057party's public key and returns the computed shared secret. The supplied 1058key is interpreted using specified <code>inputEncoding</code>, and the returned secret 1059is encoded using the specified <code>outputEncoding</code>. 1060If the <code>inputEncoding</code> is not 1061provided, <code>otherPublicKey</code> is expected to be a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or 1062<code>DataView</code>.</p> 1063<p>If <code>outputEncoding</code> is given a string will be returned; otherwise a 1064<a href="buffer.html"><code>Buffer</code></a> is returned.</p> 1065<p><code>ecdh.computeSecret</code> will throw an 1066<code>ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY</code> error when <code>otherPublicKey</code> 1067lies outside of the elliptic curve. Since <code>otherPublicKey</code> is 1068usually supplied from a remote user over an insecure network, 1069be sure to handle this exception accordingly.</p> 1070<h4><code>ecdh.generateKeys([encoding[, format]])</code><span><a class="mark" href="#crypto_ecdh_generatekeys_encoding_format" id="crypto_ecdh_generatekeys_encoding_format">#</a></span></h4> 1071<div class="api_metadata"> 1072<span>Added in: v0.11.14</span> 1073</div> 1074<ul> 1075<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 1076<li><code>format</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> <strong>Default:</strong> <code>'uncompressed'</code></li> 1077<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1078</ul> 1079<p>Generates private and public EC Diffie-Hellman key values, and returns 1080the public key in the specified <code>format</code> and <code>encoding</code>. This key should be 1081transferred to the other party.</p> 1082<p>The <code>format</code> argument specifies point encoding and can be <code>'compressed'</code> or 1083<code>'uncompressed'</code>. If <code>format</code> is not specified, the point will be returned in 1084<code>'uncompressed'</code> format.</p> 1085<p>If <code>encoding</code> is provided a string is returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> 1086is returned.</p> 1087<h4><code>ecdh.getPrivateKey([encoding])</code><span><a class="mark" href="#crypto_ecdh_getprivatekey_encoding" id="crypto_ecdh_getprivatekey_encoding">#</a></span></h4> 1088<div class="api_metadata"> 1089<span>Added in: v0.11.14</span> 1090</div> 1091<ul> 1092<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 1093<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The EC Diffie-Hellman in the specified <code>encoding</code>.</li> 1094</ul> 1095<p>If <code>encoding</code> is specified, a string is returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> is 1096returned.</p> 1097<h4><code>ecdh.getPublicKey([encoding][, format])</code><span><a class="mark" href="#crypto_ecdh_getpublickey_encoding_format" id="crypto_ecdh_getpublickey_encoding_format">#</a></span></h4> 1098<div class="api_metadata"> 1099<span>Added in: v0.11.14</span> 1100</div> 1101<ul> 1102<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 1103<li><code>format</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> <strong>Default:</strong> <code>'uncompressed'</code></li> 1104<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The EC Diffie-Hellman public key in the specified 1105<code>encoding</code> and <code>format</code>.</li> 1106</ul> 1107<p>The <code>format</code> argument specifies point encoding and can be <code>'compressed'</code> or 1108<code>'uncompressed'</code>. If <code>format</code> is not specified the point will be returned in 1109<code>'uncompressed'</code> format.</p> 1110<p>If <code>encoding</code> is specified, a string is returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> is 1111returned.</p> 1112<h4><code>ecdh.setPrivateKey(privateKey[, encoding])</code><span><a class="mark" href="#crypto_ecdh_setprivatekey_privatekey_encoding" id="crypto_ecdh_setprivatekey_privatekey_encoding">#</a></span></h4> 1113<div class="api_metadata"> 1114<span>Added in: v0.11.14</span> 1115</div> 1116<ul> 1117<li><code>privateKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1118<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>privateKey</code> string.</li> 1119</ul> 1120<p>Sets the EC Diffie-Hellman private key. 1121If <code>encoding</code> is provided, <code>privateKey</code> is expected 1122to be a string; otherwise <code>privateKey</code> is expected to be a <a href="buffer.html"><code>Buffer</code></a>, 1123<code>TypedArray</code>, or <code>DataView</code>.</p> 1124<p>If <code>privateKey</code> is not valid for the curve specified when the <code>ECDH</code> object was 1125created, an error is thrown. Upon setting the private key, the associated 1126public point (key) is also generated and set in the <code>ECDH</code> object.</p> 1127<h4><code>ecdh.setPublicKey(publicKey[, encoding])</code><span><a class="mark" href="#crypto_ecdh_setpublickey_publickey_encoding" id="crypto_ecdh_setpublickey_publickey_encoding">#</a></span></h4> 1128<div class="api_metadata"> 1129<span>Added in: v0.11.14</span><span>Deprecated since: v5.2.0</span> 1130</div> 1131<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated</div><p></p> 1132<ul> 1133<li><code>publicKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1134<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>publicKey</code> string.</li> 1135</ul> 1136<p>Sets the EC Diffie-Hellman public key. 1137If <code>encoding</code> is provided <code>publicKey</code> is expected to 1138be a string; otherwise a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or <code>DataView</code> is expected.</p> 1139<p>There is not normally a reason to call this method because <code>ECDH</code> 1140only requires a private key and the other party's public key to compute the 1141shared secret. Typically either <a href="#crypto_ecdh_generatekeys_encoding_format"><code>ecdh.generateKeys()</code></a> or 1142<a href="#crypto_ecdh_setprivatekey_privatekey_encoding"><code>ecdh.setPrivateKey()</code></a> will be called. The <a href="#crypto_ecdh_setprivatekey_privatekey_encoding"><code>ecdh.setPrivateKey()</code></a> method 1143attempts to generate the public point/key associated with the private key being 1144set.</p> 1145<p>Example (obtaining a shared secret):</p> 1146<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1147<span class="hljs-keyword">const</span> alice = crypto.<span class="hljs-title function_">createECDH</span>(<span class="hljs-string">'secp256k1'</span>); 1148<span class="hljs-keyword">const</span> bob = crypto.<span class="hljs-title function_">createECDH</span>(<span class="hljs-string">'secp256k1'</span>); 1149 1150<span class="hljs-comment">// This is a shortcut way of specifying one of Alice's previous private</span> 1151<span class="hljs-comment">// keys. It would be unwise to use such a predictable private key in a real</span> 1152<span class="hljs-comment">// application.</span> 1153alice.<span class="hljs-title function_">setPrivateKey</span>( 1154 crypto.<span class="hljs-title function_">createHash</span>(<span class="hljs-string">'sha256'</span>).<span class="hljs-title function_">update</span>(<span class="hljs-string">'alice'</span>, <span class="hljs-string">'utf8'</span>).<span class="hljs-title function_">digest</span>() 1155); 1156 1157<span class="hljs-comment">// Bob uses a newly generated cryptographically strong</span> 1158<span class="hljs-comment">// pseudorandom key pair</span> 1159bob.<span class="hljs-title function_">generateKeys</span>(); 1160 1161<span class="hljs-keyword">const</span> aliceSecret = alice.<span class="hljs-title function_">computeSecret</span>(bob.<span class="hljs-title function_">getPublicKey</span>(), <span class="hljs-literal">null</span>, <span class="hljs-string">'hex'</span>); 1162<span class="hljs-keyword">const</span> bobSecret = bob.<span class="hljs-title function_">computeSecret</span>(alice.<span class="hljs-title function_">getPublicKey</span>(), <span class="hljs-literal">null</span>, <span class="hljs-string">'hex'</span>); 1163 1164<span class="hljs-comment">// aliceSecret and bobSecret should be the same shared secret value</span> 1165<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(aliceSecret === bobSecret);</code></pre> 1166</section><section><h3>Class: <code>Hash</code><span><a class="mark" href="#crypto_class_hash" id="crypto_class_hash">#</a></span></h3> 1167<div class="api_metadata"> 1168<span>Added in: v0.1.92</span> 1169</div> 1170<ul> 1171<li>Extends: <a href="stream.html#stream_class_stream_transform" class="type"><stream.Transform></a></li> 1172</ul> 1173<p>The <code>Hash</code> class is a utility for creating hash digests of data. It can be 1174used in one of two ways:</p> 1175<ul> 1176<li>As a <a href="stream.html">stream</a> that is both readable and writable, where data is written 1177to produce a computed hash digest on the readable side, or</li> 1178<li>Using the <a href="#crypto_hash_update_data_inputencoding"><code>hash.update()</code></a> and <a href="#crypto_hash_digest_encoding"><code>hash.digest()</code></a> methods to produce the 1179computed hash.</li> 1180</ul> 1181<p>The <a href="#crypto_crypto_createhash_algorithm_options"><code>crypto.createHash()</code></a> method is used to create <code>Hash</code> instances. <code>Hash</code> 1182objects are not to be created directly using the <code>new</code> keyword.</p> 1183<p>Example: Using <code>Hash</code> objects as streams:</p> 1184<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1185<span class="hljs-keyword">const</span> hash = crypto.<span class="hljs-title function_">createHash</span>(<span class="hljs-string">'sha256'</span>); 1186 1187hash.<span class="hljs-title function_">on</span>(<span class="hljs-string">'readable'</span>, <span class="hljs-function">() =></span> { 1188 <span class="hljs-comment">// Only one element is going to be produced by the</span> 1189 <span class="hljs-comment">// hash stream.</span> 1190 <span class="hljs-keyword">const</span> data = hash.<span class="hljs-title function_">read</span>(); 1191 <span class="hljs-keyword">if</span> (data) { 1192 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(data.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 1193 <span class="hljs-comment">// Prints:</span> 1194 <span class="hljs-comment">// 6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50</span> 1195 } 1196}); 1197 1198hash.<span class="hljs-title function_">write</span>(<span class="hljs-string">'some data to hash'</span>); 1199hash.<span class="hljs-title function_">end</span>();</code></pre> 1200<p>Example: Using <code>Hash</code> and piped streams:</p> 1201<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1202<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 1203<span class="hljs-keyword">const</span> hash = crypto.<span class="hljs-title function_">createHash</span>(<span class="hljs-string">'sha256'</span>); 1204 1205<span class="hljs-keyword">const</span> input = fs.<span class="hljs-title function_">createReadStream</span>(<span class="hljs-string">'test.js'</span>); 1206input.<span class="hljs-title function_">pipe</span>(hash).<span class="hljs-title function_">setEncoding</span>(<span class="hljs-string">'hex'</span>).<span class="hljs-title function_">pipe</span>(process.<span class="hljs-property">stdout</span>);</code></pre> 1207<p>Example: Using the <a href="#crypto_hash_update_data_inputencoding"><code>hash.update()</code></a> and <a href="#crypto_hash_digest_encoding"><code>hash.digest()</code></a> methods:</p> 1208<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1209<span class="hljs-keyword">const</span> hash = crypto.<span class="hljs-title function_">createHash</span>(<span class="hljs-string">'sha256'</span>); 1210 1211hash.<span class="hljs-title function_">update</span>(<span class="hljs-string">'some data to hash'</span>); 1212<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(hash.<span class="hljs-title function_">digest</span>(<span class="hljs-string">'hex'</span>)); 1213<span class="hljs-comment">// Prints:</span> 1214<span class="hljs-comment">// 6a2da20943931e9834fc12cfe5bb47bbd9ae43489a30726962b576f4e3993e50</span></code></pre> 1215<h4><code>hash.copy([options])</code><span><a class="mark" href="#crypto_hash_copy_options" id="crypto_hash_copy_options">#</a></span></h4> 1216<div class="api_metadata"> 1217<span>Added in: v13.1.0</span> 1218</div> 1219<ul> 1220<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a></li> 1221<li>Returns: <a href="crypto.html#crypto_class_hash" class="type"><Hash></a></li> 1222</ul> 1223<p>Creates a new <code>Hash</code> object that contains a deep copy of the internal state 1224of the current <code>Hash</code> object.</p> 1225<p>The optional <code>options</code> argument controls stream behavior. For XOF hash 1226functions such as <code>'shake256'</code>, the <code>outputLength</code> option can be used to 1227specify the desired output length in bytes.</p> 1228<p>An error is thrown when an attempt is made to copy the <code>Hash</code> object after 1229its <a href="#crypto_hash_digest_encoding"><code>hash.digest()</code></a> method has been called.</p> 1230<pre><code class="language-js"><span class="hljs-comment">// Calculate a rolling hash.</span> 1231<span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1232<span class="hljs-keyword">const</span> hash = crypto.<span class="hljs-title function_">createHash</span>(<span class="hljs-string">'sha256'</span>); 1233 1234hash.<span class="hljs-title function_">update</span>(<span class="hljs-string">'one'</span>); 1235<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(hash.<span class="hljs-title function_">copy</span>().<span class="hljs-title function_">digest</span>(<span class="hljs-string">'hex'</span>)); 1236 1237hash.<span class="hljs-title function_">update</span>(<span class="hljs-string">'two'</span>); 1238<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(hash.<span class="hljs-title function_">copy</span>().<span class="hljs-title function_">digest</span>(<span class="hljs-string">'hex'</span>)); 1239 1240hash.<span class="hljs-title function_">update</span>(<span class="hljs-string">'three'</span>); 1241<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(hash.<span class="hljs-title function_">copy</span>().<span class="hljs-title function_">digest</span>(<span class="hljs-string">'hex'</span>)); 1242 1243<span class="hljs-comment">// Etc.</span></code></pre> 1244<h4><code>hash.digest([encoding])</code><span><a class="mark" href="#crypto_hash_digest_encoding" id="crypto_hash_digest_encoding">#</a></span></h4> 1245<div class="api_metadata"> 1246<span>Added in: v0.1.92</span> 1247</div> 1248<ul> 1249<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 1250<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1251</ul> 1252<p>Calculates the digest of all of the data passed to be hashed (using the 1253<a href="#crypto_hash_update_data_inputencoding"><code>hash.update()</code></a> method). 1254If <code>encoding</code> is provided a string will be returned; otherwise 1255a <a href="buffer.html"><code>Buffer</code></a> is returned.</p> 1256<p>The <code>Hash</code> object can not be used again after <code>hash.digest()</code> method has been 1257called. Multiple calls will cause an error to be thrown.</p> 1258<h4><code>hash.update(data[, inputEncoding])</code><span><a class="mark" href="#crypto_hash_update_data_inputencoding" id="crypto_hash_update_data_inputencoding">#</a></span></h4> 1259<div class="api_metadata"> 1260<details class="changelog"><summary>History</summary> 1261<table> 1262<tbody><tr><th>Version</th><th>Changes</th></tr> 1263<tr><td>v6.0.0</td> 1264<td><p>The default <code>inputEncoding</code> changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 1265<tr><td>v0.1.92</td> 1266<td><p><span>Added in: v0.1.92</span></p></td></tr> 1267</tbody></table> 1268</details> 1269</div> 1270<ul> 1271<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1272<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>data</code> string.</li> 1273</ul> 1274<p>Updates the hash content with the given <code>data</code>, the encoding of which 1275is given in <code>inputEncoding</code>. 1276If <code>encoding</code> is not provided, and the <code>data</code> is a string, an 1277encoding of <code>'utf8'</code> is enforced. If <code>data</code> is a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or 1278<code>DataView</code>, then <code>inputEncoding</code> is ignored.</p> 1279<p>This can be called many times with new data as it is streamed.</p> 1280</section><section><h3>Class: <code>Hmac</code><span><a class="mark" href="#crypto_class_hmac" id="crypto_class_hmac">#</a></span></h3> 1281<div class="api_metadata"> 1282<span>Added in: v0.1.94</span> 1283</div> 1284<ul> 1285<li>Extends: <a href="stream.html#stream_class_stream_transform" class="type"><stream.Transform></a></li> 1286</ul> 1287<p>The <code>Hmac</code> class is a utility for creating cryptographic HMAC digests. It can 1288be used in one of two ways:</p> 1289<ul> 1290<li>As a <a href="stream.html">stream</a> that is both readable and writable, where data is written 1291to produce a computed HMAC digest on the readable side, or</li> 1292<li>Using the <a href="#crypto_hmac_update_data_inputencoding"><code>hmac.update()</code></a> and <a href="#crypto_hmac_digest_encoding"><code>hmac.digest()</code></a> methods to produce the 1293computed HMAC digest.</li> 1294</ul> 1295<p>The <a href="#crypto_crypto_createhmac_algorithm_key_options"><code>crypto.createHmac()</code></a> method is used to create <code>Hmac</code> instances. <code>Hmac</code> 1296objects are not to be created directly using the <code>new</code> keyword.</p> 1297<p>Example: Using <code>Hmac</code> objects as streams:</p> 1298<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1299<span class="hljs-keyword">const</span> hmac = crypto.<span class="hljs-title function_">createHmac</span>(<span class="hljs-string">'sha256'</span>, <span class="hljs-string">'a secret'</span>); 1300 1301hmac.<span class="hljs-title function_">on</span>(<span class="hljs-string">'readable'</span>, <span class="hljs-function">() =></span> { 1302 <span class="hljs-comment">// Only one element is going to be produced by the</span> 1303 <span class="hljs-comment">// hash stream.</span> 1304 <span class="hljs-keyword">const</span> data = hmac.<span class="hljs-title function_">read</span>(); 1305 <span class="hljs-keyword">if</span> (data) { 1306 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(data.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 1307 <span class="hljs-comment">// Prints:</span> 1308 <span class="hljs-comment">// 7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e</span> 1309 } 1310}); 1311 1312hmac.<span class="hljs-title function_">write</span>(<span class="hljs-string">'some data to hash'</span>); 1313hmac.<span class="hljs-title function_">end</span>();</code></pre> 1314<p>Example: Using <code>Hmac</code> and piped streams:</p> 1315<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1316<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 1317<span class="hljs-keyword">const</span> hmac = crypto.<span class="hljs-title function_">createHmac</span>(<span class="hljs-string">'sha256'</span>, <span class="hljs-string">'a secret'</span>); 1318 1319<span class="hljs-keyword">const</span> input = fs.<span class="hljs-title function_">createReadStream</span>(<span class="hljs-string">'test.js'</span>); 1320input.<span class="hljs-title function_">pipe</span>(hmac).<span class="hljs-title function_">pipe</span>(process.<span class="hljs-property">stdout</span>);</code></pre> 1321<p>Example: Using the <a href="#crypto_hmac_update_data_inputencoding"><code>hmac.update()</code></a> and <a href="#crypto_hmac_digest_encoding"><code>hmac.digest()</code></a> methods:</p> 1322<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1323<span class="hljs-keyword">const</span> hmac = crypto.<span class="hljs-title function_">createHmac</span>(<span class="hljs-string">'sha256'</span>, <span class="hljs-string">'a secret'</span>); 1324 1325hmac.<span class="hljs-title function_">update</span>(<span class="hljs-string">'some data to hash'</span>); 1326<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(hmac.<span class="hljs-title function_">digest</span>(<span class="hljs-string">'hex'</span>)); 1327<span class="hljs-comment">// Prints:</span> 1328<span class="hljs-comment">// 7fd04df92f636fd450bc841c9418e5825c17f33ad9c87c518115a45971f7f77e</span></code></pre> 1329<h4><code>hmac.digest([encoding])</code><span><a class="mark" href="#crypto_hmac_digest_encoding" id="crypto_hmac_digest_encoding">#</a></span></h4> 1330<div class="api_metadata"> 1331<span>Added in: v0.1.94</span> 1332</div> 1333<ul> 1334<li><code>encoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 1335<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1336</ul> 1337<p>Calculates the HMAC digest of all of the data passed using <a href="#crypto_hmac_update_data_inputencoding"><code>hmac.update()</code></a>. 1338If <code>encoding</code> is 1339provided a string is returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> is returned;</p> 1340<p>The <code>Hmac</code> object can not be used again after <code>hmac.digest()</code> has been 1341called. Multiple calls to <code>hmac.digest()</code> will result in an error being thrown.</p> 1342<h4><code>hmac.update(data[, inputEncoding])</code><span><a class="mark" href="#crypto_hmac_update_data_inputencoding" id="crypto_hmac_update_data_inputencoding">#</a></span></h4> 1343<div class="api_metadata"> 1344<details class="changelog"><summary>History</summary> 1345<table> 1346<tbody><tr><th>Version</th><th>Changes</th></tr> 1347<tr><td>v6.0.0</td> 1348<td><p>The default <code>inputEncoding</code> changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 1349<tr><td>v0.1.94</td> 1350<td><p><span>Added in: v0.1.94</span></p></td></tr> 1351</tbody></table> 1352</details> 1353</div> 1354<ul> 1355<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1356<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>data</code> string.</li> 1357</ul> 1358<p>Updates the <code>Hmac</code> content with the given <code>data</code>, the encoding of which 1359is given in <code>inputEncoding</code>. 1360If <code>encoding</code> is not provided, and the <code>data</code> is a string, an 1361encoding of <code>'utf8'</code> is enforced. If <code>data</code> is a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or 1362<code>DataView</code>, then <code>inputEncoding</code> is ignored.</p> 1363<p>This can be called many times with new data as it is streamed.</p> 1364</section><section><h3>Class: <code>KeyObject</code><span><a class="mark" href="#crypto_class_keyobject" id="crypto_class_keyobject">#</a></span></h3> 1365<div class="api_metadata"> 1366<details class="changelog"><summary>History</summary> 1367<table> 1368<tbody><tr><th>Version</th><th>Changes</th></tr> 1369<tr><td>v14.5.0</td> 1370<td><p>Instances of this class can now be passed to worker threads using <code>postMessage</code>.</p></td></tr> 1371<tr><td>v11.13.0</td> 1372<td><p>This class is now exported.</p></td></tr> 1373<tr><td>v11.6.0</td> 1374<td><p><span>Added in: v11.6.0</span></p></td></tr> 1375</tbody></table> 1376</details> 1377</div> 1378<p>Node.js uses a <code>KeyObject</code> class to represent a symmetric or asymmetric key, 1379and each kind of key exposes different functions. The 1380<a href="#crypto_crypto_createsecretkey_key"><code>crypto.createSecretKey()</code></a>, <a href="#crypto_crypto_createpublickey_key"><code>crypto.createPublicKey()</code></a> and 1381<a href="#crypto_crypto_createprivatekey_key"><code>crypto.createPrivateKey()</code></a> methods are used to create <code>KeyObject</code> 1382instances. <code>KeyObject</code> objects are not to be created directly using the <code>new</code> 1383keyword.</p> 1384<p>Most applications should consider using the new <code>KeyObject</code> API instead of 1385passing keys as strings or <code>Buffer</code>s due to improved security features.</p> 1386<p><code>KeyObject</code> instances can be passed to other threads via <a href="worker_threads.html#worker_threads_port_postmessage_value_transferlist"><code>postMessage()</code></a>. 1387The receiver obtains a cloned <code>KeyObject</code>, and the <code>KeyObject</code> does not need to 1388be listed in the <code>transferList</code> argument.</p> 1389<h4><code>keyObject.asymmetricKeyType</code><span><a class="mark" href="#crypto_keyobject_asymmetrickeytype" id="crypto_keyobject_asymmetrickeytype">#</a></span></h4> 1390<div class="api_metadata"> 1391<details class="changelog"><summary>History</summary> 1392<table> 1393<tbody><tr><th>Version</th><th>Changes</th></tr> 1394<tr><td>v13.9.0</td> 1395<td><p>Added support for <code>'dh'</code>.</p></td></tr> 1396<tr><td>v12.0.0</td> 1397<td><p>Added support for <code>'rsa-pss'</code>.</p></td></tr> 1398<tr><td>v12.0.0</td> 1399<td><p>This property now returns <code>undefined</code> for KeyObject instances of unrecognized type instead of aborting.</p></td></tr> 1400<tr><td>v12.0.0</td> 1401<td><p>Added support for <code>'x25519'</code> and <code>'x448'</code>.</p></td></tr> 1402<tr><td>v12.0.0</td> 1403<td><p>Added support for <code>'ed25519'</code> and <code>'ed448'</code>.</p></td></tr> 1404<tr><td>v11.6.0</td> 1405<td><p><span>Added in: v11.6.0</span></p></td></tr> 1406</tbody></table> 1407</details> 1408</div> 1409<ul> 1410<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1411</ul> 1412<p>For asymmetric keys, this property represents the type of the key. Supported key 1413types are:</p> 1414<ul> 1415<li><code>'rsa'</code> (OID 1.2.840.113549.1.1.1)</li> 1416<li><code>'rsa-pss'</code> (OID 1.2.840.113549.1.1.10)</li> 1417<li><code>'dsa'</code> (OID 1.2.840.10040.4.1)</li> 1418<li><code>'ec'</code> (OID 1.2.840.10045.2.1)</li> 1419<li><code>'x25519'</code> (OID 1.3.101.110)</li> 1420<li><code>'x448'</code> (OID 1.3.101.111)</li> 1421<li><code>'ed25519'</code> (OID 1.3.101.112)</li> 1422<li><code>'ed448'</code> (OID 1.3.101.113)</li> 1423<li><code>'dh'</code> (OID 1.2.840.113549.1.3.1)</li> 1424</ul> 1425<p>This property is <code>undefined</code> for unrecognized <code>KeyObject</code> types and symmetric 1426keys.</p> 1427<h4><code>keyObject.export([options])</code><span><a class="mark" href="#crypto_keyobject_export_options" id="crypto_keyobject_export_options">#</a></span></h4> 1428<div class="api_metadata"> 1429<span>Added in: v11.6.0</span> 1430</div> 1431<ul> 1432<li><code>options</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 1433<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 1434</ul> 1435<p>For symmetric keys, this function allocates a <code>Buffer</code> containing the key 1436material and ignores any options.</p> 1437<p>For asymmetric keys, the <code>options</code> parameter is used to determine the export 1438format.</p> 1439<p>For public keys, the following encoding options can be used:</p> 1440<ul> 1441<li><code>type</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be one of <code>'pkcs1'</code> (RSA only) or <code>'spki'</code>.</li> 1442<li><code>format</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'pem'</code> or <code>'der'</code>.</li> 1443</ul> 1444<p>For private keys, the following encoding options can be used:</p> 1445<ul> 1446<li><code>type</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be one of <code>'pkcs1'</code> (RSA only), <code>'pkcs8'</code> or 1447<code>'sec1'</code> (EC only).</li> 1448<li><code>format</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'pem'</code> or <code>'der'</code>.</li> 1449<li><code>cipher</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> If specified, the private key will be encrypted with 1450the given <code>cipher</code> and <code>passphrase</code> using PKCS#5 v2.0 password based 1451encryption.</li> 1452<li><code>passphrase</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The passphrase to use for encryption, see 1453<code>cipher</code>.</li> 1454</ul> 1455<p>When PEM encoding was selected, the result will be a string, otherwise it will 1456be a buffer containing the data encoded as DER.</p> 1457<p>PKCS#1, SEC1, and PKCS#8 type keys can be encrypted by using a combination of 1458the <code>cipher</code> and <code>format</code> options. The PKCS#8 <code>type</code> can be used with any 1459<code>format</code> to encrypt any key algorithm (RSA, EC, or DH) by specifying a 1460<code>cipher</code>. PKCS#1 and SEC1 can only be encrypted by specifying a <code>cipher</code> 1461when the PEM <code>format</code> is used. For maximum compatibility, use PKCS#8 for 1462encrypted private keys. Since PKCS#8 defines its own 1463encryption mechanism, PEM-level encryption is not supported when encrypting 1464a PKCS#8 key. See <a href="https://www.rfc-editor.org/rfc/rfc5208.txt">RFC 5208</a> for PKCS#8 encryption and <a href="https://www.rfc-editor.org/rfc/rfc1421.txt">RFC 1421</a> for 1465PKCS#1 and SEC1 encryption.</p> 1466<h4><code>keyObject.symmetricKeySize</code><span><a class="mark" href="#crypto_keyobject_symmetrickeysize" id="crypto_keyobject_symmetrickeysize">#</a></span></h4> 1467<div class="api_metadata"> 1468<span>Added in: v11.6.0</span> 1469</div> 1470<ul> 1471<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 1472</ul> 1473<p>For secret keys, this property represents the size of the key in bytes. This 1474property is <code>undefined</code> for asymmetric keys.</p> 1475<h4><code>keyObject.type</code><span><a class="mark" href="#crypto_keyobject_type" id="crypto_keyobject_type">#</a></span></h4> 1476<div class="api_metadata"> 1477<span>Added in: v11.6.0</span> 1478</div> 1479<ul> 1480<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1481</ul> 1482<p>Depending on the type of this <code>KeyObject</code>, this property is either 1483<code>'secret'</code> for secret (symmetric) keys, <code>'public'</code> for public (asymmetric) keys 1484or <code>'private'</code> for private (asymmetric) keys.</p> 1485</section><section><h3>Class: <code>Sign</code><span><a class="mark" href="#crypto_class_sign" id="crypto_class_sign">#</a></span></h3> 1486<div class="api_metadata"> 1487<span>Added in: v0.1.92</span> 1488</div> 1489<ul> 1490<li>Extends: <a href="stream.html#stream_class_stream_writable" class="type"><stream.Writable></a></li> 1491</ul> 1492<p>The <code>Sign</code> class is a utility for generating signatures. It can be used in one 1493of two ways:</p> 1494<ul> 1495<li>As a writable <a href="stream.html">stream</a>, where data to be signed is written and the 1496<a href="#crypto_sign_sign_privatekey_outputencoding"><code>sign.sign()</code></a> method is used to generate and return the signature, or</li> 1497<li>Using the <a href="#crypto_sign_update_data_inputencoding"><code>sign.update()</code></a> and <a href="#crypto_sign_sign_privatekey_outputencoding"><code>sign.sign()</code></a> methods to produce the 1498signature.</li> 1499</ul> 1500<p>The <a href="#crypto_crypto_createsign_algorithm_options"><code>crypto.createSign()</code></a> method is used to create <code>Sign</code> instances. The 1501argument is the string name of the hash function to use. <code>Sign</code> objects are not 1502to be created directly using the <code>new</code> keyword.</p> 1503<p>Example: Using <code>Sign</code> and <a href="#crypto_class_verify"><code>Verify</code></a> objects as streams:</p> 1504<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1505 1506<span class="hljs-keyword">const</span> { privateKey, publicKey } = crypto.<span class="hljs-title function_">generateKeyPairSync</span>(<span class="hljs-string">'ec'</span>, { 1507 <span class="hljs-attr">namedCurve</span>: <span class="hljs-string">'sect239k1'</span> 1508}); 1509 1510<span class="hljs-keyword">const</span> sign = crypto.<span class="hljs-title function_">createSign</span>(<span class="hljs-string">'SHA256'</span>); 1511sign.<span class="hljs-title function_">write</span>(<span class="hljs-string">'some data to sign'</span>); 1512sign.<span class="hljs-title function_">end</span>(); 1513<span class="hljs-keyword">const</span> signature = sign.<span class="hljs-title function_">sign</span>(privateKey, <span class="hljs-string">'hex'</span>); 1514 1515<span class="hljs-keyword">const</span> verify = crypto.<span class="hljs-title function_">createVerify</span>(<span class="hljs-string">'SHA256'</span>); 1516verify.<span class="hljs-title function_">write</span>(<span class="hljs-string">'some data to sign'</span>); 1517verify.<span class="hljs-title function_">end</span>(); 1518<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(verify.<span class="hljs-title function_">verify</span>(publicKey, signature, <span class="hljs-string">'hex'</span>)); 1519<span class="hljs-comment">// Prints: true</span></code></pre> 1520<p>Example: Using the <a href="#crypto_sign_update_data_inputencoding"><code>sign.update()</code></a> and <a href="#crypto_verify_update_data_inputencoding"><code>verify.update()</code></a> methods:</p> 1521<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 1522 1523<span class="hljs-keyword">const</span> { privateKey, publicKey } = crypto.<span class="hljs-title function_">generateKeyPairSync</span>(<span class="hljs-string">'rsa'</span>, { 1524 <span class="hljs-attr">modulusLength</span>: <span class="hljs-number">2048</span>, 1525}); 1526 1527<span class="hljs-keyword">const</span> sign = crypto.<span class="hljs-title function_">createSign</span>(<span class="hljs-string">'SHA256'</span>); 1528sign.<span class="hljs-title function_">update</span>(<span class="hljs-string">'some data to sign'</span>); 1529sign.<span class="hljs-title function_">end</span>(); 1530<span class="hljs-keyword">const</span> signature = sign.<span class="hljs-title function_">sign</span>(privateKey); 1531 1532<span class="hljs-keyword">const</span> verify = crypto.<span class="hljs-title function_">createVerify</span>(<span class="hljs-string">'SHA256'</span>); 1533verify.<span class="hljs-title function_">update</span>(<span class="hljs-string">'some data to sign'</span>); 1534verify.<span class="hljs-title function_">end</span>(); 1535<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(verify.<span class="hljs-title function_">verify</span>(publicKey, signature)); 1536<span class="hljs-comment">// Prints: true</span></code></pre> 1537<h4><code>sign.sign(privateKey[, outputEncoding])</code><span><a class="mark" href="#crypto_sign_sign_privatekey_outputencoding" id="crypto_sign_sign_privatekey_outputencoding">#</a></span></h4> 1538<div class="api_metadata"> 1539<details class="changelog"><summary>History</summary> 1540<table> 1541<tbody><tr><th>Version</th><th>Changes</th></tr> 1542<tr><td>v13.2.0, v12.16.0</td> 1543<td><p>This function now supports IEEE-P1363 DSA and ECDSA signatures.</p></td></tr> 1544<tr><td>v12.0.0</td> 1545<td><p>This function now supports RSA-PSS keys.</p></td></tr> 1546<tr><td>v11.6.0</td> 1547<td><p>This function now supports key objects.</p></td></tr> 1548<tr><td>v8.0.0</td> 1549<td><p>Support for RSASSA-PSS and additional options was added.</p></td></tr> 1550<tr><td>v0.1.92</td> 1551<td><p><span>Added in: v0.1.92</span></p></td></tr> 1552</tbody></table> 1553</details> 1554</div> 1555<ul> 1556<li><code>privateKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> 1557<ul> 1558<li><code>dsaEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1559<li><code>padding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a></li> 1560<li><code>saltLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a></li> 1561</ul> 1562</li> 1563<li><code>outputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the return value.</li> 1564<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1565</ul> 1566<p>Calculates the signature on all the data passed through using either 1567<a href="#crypto_sign_update_data_inputencoding"><code>sign.update()</code></a> or <a href="stream.html#stream_writable_write_chunk_encoding_callback"><code>sign.write()</code></a>.</p> 1568<p>If <code>privateKey</code> is not a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, this function behaves as if 1569<code>privateKey</code> had been passed to <a href="#crypto_crypto_createprivatekey_key"><code>crypto.createPrivateKey()</code></a>. If it is an 1570object, the following additional properties can be passed:</p> 1571<ul> 1572<li> 1573<p><code>dsaEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> For DSA and ECDSA, this option specifies the 1574format of the generated signature. It can be one of the following:</p> 1575<ul> 1576<li><code>'der'</code> (default): DER-encoded ASN.1 signature structure encoding <code>(r, s)</code>.</li> 1577<li><code>'ieee-p1363'</code>: Signature format <code>r || s</code> as proposed in IEEE-P1363.</li> 1578</ul> 1579</li> 1580<li> 1581<p><code>padding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Optional padding value for RSA, one of the following:</p> 1582<ul> 1583<li><code>crypto.constants.RSA_PKCS1_PADDING</code> (default)</li> 1584<li><code>crypto.constants.RSA_PKCS1_PSS_PADDING</code></li> 1585</ul> 1586<p><code>RSA_PKCS1_PSS_PADDING</code> will use MGF1 with the same hash function 1587used to sign the message as specified in section 3.1 of <a href="https://www.rfc-editor.org/rfc/rfc4055.txt">RFC 4055</a>, unless 1588an MGF1 hash function has been specified as part of the key in compliance with 1589section 3.3 of <a href="https://www.rfc-editor.org/rfc/rfc4055.txt">RFC 4055</a>.</p> 1590</li> 1591<li> 1592<p><code>saltLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Salt length for when padding is 1593<code>RSA_PKCS1_PSS_PADDING</code>. The special value 1594<code>crypto.constants.RSA_PSS_SALTLEN_DIGEST</code> sets the salt length to the digest 1595size, <code>crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN</code> (default) sets it to the 1596maximum permissible value.</p> 1597</li> 1598</ul> 1599<p>If <code>outputEncoding</code> is provided a string is returned; otherwise a <a href="buffer.html"><code>Buffer</code></a> 1600is returned.</p> 1601<p>The <code>Sign</code> object can not be again used after <code>sign.sign()</code> method has been 1602called. Multiple calls to <code>sign.sign()</code> will result in an error being thrown.</p> 1603<h4><code>sign.update(data[, inputEncoding])</code><span><a class="mark" href="#crypto_sign_update_data_inputencoding" id="crypto_sign_update_data_inputencoding">#</a></span></h4> 1604<div class="api_metadata"> 1605<details class="changelog"><summary>History</summary> 1606<table> 1607<tbody><tr><th>Version</th><th>Changes</th></tr> 1608<tr><td>v6.0.0</td> 1609<td><p>The default <code>inputEncoding</code> changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 1610<tr><td>v0.1.92</td> 1611<td><p><span>Added in: v0.1.92</span></p></td></tr> 1612</tbody></table> 1613</details> 1614</div> 1615<ul> 1616<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1617<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>data</code> string.</li> 1618</ul> 1619<p>Updates the <code>Sign</code> content with the given <code>data</code>, the encoding of which 1620is given in <code>inputEncoding</code>. 1621If <code>encoding</code> is not provided, and the <code>data</code> is a string, an 1622encoding of <code>'utf8'</code> is enforced. If <code>data</code> is a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or 1623<code>DataView</code>, then <code>inputEncoding</code> is ignored.</p> 1624<p>This can be called many times with new data as it is streamed.</p> 1625</section><section><h3>Class: <code>Verify</code><span><a class="mark" href="#crypto_class_verify" id="crypto_class_verify">#</a></span></h3> 1626<div class="api_metadata"> 1627<span>Added in: v0.1.92</span> 1628</div> 1629<ul> 1630<li>Extends: <a href="stream.html#stream_class_stream_writable" class="type"><stream.Writable></a></li> 1631</ul> 1632<p>The <code>Verify</code> class is a utility for verifying signatures. It can be used in one 1633of two ways:</p> 1634<ul> 1635<li>As a writable <a href="stream.html">stream</a> where written data is used to validate against the 1636supplied signature, or</li> 1637<li>Using the <a href="#crypto_verify_update_data_inputencoding"><code>verify.update()</code></a> and <a href="#crypto_verify_verify_object_signature_signatureencoding"><code>verify.verify()</code></a> methods to verify 1638the signature.</li> 1639</ul> 1640<p>The <a href="#crypto_crypto_createverify_algorithm_options"><code>crypto.createVerify()</code></a> method is used to create <code>Verify</code> instances. 1641<code>Verify</code> objects are not to be created directly using the <code>new</code> keyword.</p> 1642<p>See <a href="#crypto_class_sign"><code>Sign</code></a> for examples.</p> 1643<h4><code>verify.update(data[, inputEncoding])</code><span><a class="mark" href="#crypto_verify_update_data_inputencoding" id="crypto_verify_update_data_inputencoding">#</a></span></h4> 1644<div class="api_metadata"> 1645<details class="changelog"><summary>History</summary> 1646<table> 1647<tbody><tr><th>Version</th><th>Changes</th></tr> 1648<tr><td>v6.0.0</td> 1649<td><p>The default <code>inputEncoding</code> changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 1650<tr><td>v0.1.92</td> 1651<td><p><span>Added in: v0.1.92</span></p></td></tr> 1652</tbody></table> 1653</details> 1654</div> 1655<ul> 1656<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1657<li><code>inputEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>data</code> string.</li> 1658</ul> 1659<p>Updates the <code>Verify</code> content with the given <code>data</code>, the encoding of which 1660is given in <code>inputEncoding</code>. 1661If <code>inputEncoding</code> is not provided, and the <code>data</code> is a string, an 1662encoding of <code>'utf8'</code> is enforced. If <code>data</code> is a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or 1663<code>DataView</code>, then <code>inputEncoding</code> is ignored.</p> 1664<p>This can be called many times with new data as it is streamed.</p> 1665<h4><code>verify.verify(object, signature[, signatureEncoding])</code><span><a class="mark" href="#crypto_verify_verify_object_signature_signatureencoding" id="crypto_verify_verify_object_signature_signatureencoding">#</a></span></h4> 1666<div class="api_metadata"> 1667<details class="changelog"><summary>History</summary> 1668<table> 1669<tbody><tr><th>Version</th><th>Changes</th></tr> 1670<tr><td>v13.2.0, v12.16.0</td> 1671<td><p>This function now supports IEEE-P1363 DSA and ECDSA signatures.</p></td></tr> 1672<tr><td>v12.0.0</td> 1673<td><p>This function now supports RSA-PSS keys.</p></td></tr> 1674<tr><td>v11.7.0</td> 1675<td><p>The key can now be a private key.</p></td></tr> 1676<tr><td>v8.0.0</td> 1677<td><p>Support for RSASSA-PSS and additional options was added.</p></td></tr> 1678<tr><td>v0.1.92</td> 1679<td><p><span>Added in: v0.1.92</span></p></td></tr> 1680</tbody></table> 1681</details> 1682</div> 1683<ul> 1684<li><code>object</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> 1685<ul> 1686<li><code>dsaEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1687<li><code>padding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a></li> 1688<li><code>saltLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a></li> 1689</ul> 1690</li> 1691<li><code>signature</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1692<li><code>signatureEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>signature</code> string.</li> 1693<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> or <code>false</code> depending on the validity of the 1694signature for the data and public key.</li> 1695</ul> 1696<p>Verifies the provided data using the given <code>object</code> and <code>signature</code>.</p> 1697<p>If <code>object</code> is not a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, this function behaves as if 1698<code>object</code> had been passed to <a href="#crypto_crypto_createpublickey_key"><code>crypto.createPublicKey()</code></a>. If it is an 1699object, the following additional properties can be passed:</p> 1700<ul> 1701<li> 1702<p><code>dsaEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> For DSA and ECDSA, this option specifies the 1703format of the signature. It can be one of the following:</p> 1704<ul> 1705<li><code>'der'</code> (default): DER-encoded ASN.1 signature structure encoding <code>(r, s)</code>.</li> 1706<li><code>'ieee-p1363'</code>: Signature format <code>r || s</code> as proposed in IEEE-P1363.</li> 1707</ul> 1708</li> 1709<li> 1710<p><code>padding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Optional padding value for RSA, one of the following:</p> 1711<ul> 1712<li><code>crypto.constants.RSA_PKCS1_PADDING</code> (default)</li> 1713<li><code>crypto.constants.RSA_PKCS1_PSS_PADDING</code></li> 1714</ul> 1715<p><code>RSA_PKCS1_PSS_PADDING</code> will use MGF1 with the same hash function 1716used to verify the message as specified in section 3.1 of <a href="https://www.rfc-editor.org/rfc/rfc4055.txt">RFC 4055</a>, unless 1717an MGF1 hash function has been specified as part of the key in compliance with 1718section 3.3 of <a href="https://www.rfc-editor.org/rfc/rfc4055.txt">RFC 4055</a>.</p> 1719</li> 1720<li> 1721<p><code>saltLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Salt length for when padding is 1722<code>RSA_PKCS1_PSS_PADDING</code>. The special value 1723<code>crypto.constants.RSA_PSS_SALTLEN_DIGEST</code> sets the salt length to the digest 1724size, <code>crypto.constants.RSA_PSS_SALTLEN_AUTO</code> (default) causes it to be 1725determined automatically.</p> 1726</li> 1727</ul> 1728<p>The <code>signature</code> argument is the previously calculated signature for the data, in 1729the <code>signatureEncoding</code>. 1730If a <code>signatureEncoding</code> is specified, the <code>signature</code> is expected to be a 1731string; otherwise <code>signature</code> is expected to be a <a href="buffer.html"><code>Buffer</code></a>, 1732<code>TypedArray</code>, or <code>DataView</code>.</p> 1733<p>The <code>verify</code> object can not be used again after <code>verify.verify()</code> has been 1734called. Multiple calls to <code>verify.verify()</code> will result in an error being 1735thrown.</p> 1736<p>Because public keys can be derived from private keys, a private key may 1737be passed instead of a public key.</p> 1738</section><section><h3><code>crypto</code> module methods and properties<span><a class="mark" href="#crypto_crypto_module_methods_and_properties" id="crypto_crypto_module_methods_and_properties">#</a></span></h3> 1739<h4><code>crypto.constants</code><span><a class="mark" href="#crypto_crypto_constants" id="crypto_crypto_constants">#</a></span></h4> 1740<div class="api_metadata"> 1741<span>Added in: v6.3.0</span> 1742</div> 1743<ul> 1744<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> An object containing commonly used constants for crypto and 1745security related operations. The specific constants currently defined are 1746described in <a href="#crypto_crypto_constants_1">Crypto constants</a>.</li> 1747</ul> 1748<h4><code>crypto.DEFAULT_ENCODING</code><span><a class="mark" href="#crypto_crypto_default_encoding" id="crypto_crypto_default_encoding">#</a></span></h4> 1749<div class="api_metadata"> 1750<span>Added in: v0.9.3</span><span>Deprecated since: v10.0.0</span> 1751</div> 1752<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated</div><p></p> 1753<p>The default encoding to use for functions that can take either strings 1754or <a href="buffer.html">buffers</a>. The default value is <code>'buffer'</code>, which makes methods 1755default to <a href="buffer.html"><code>Buffer</code></a> objects.</p> 1756<p>The <code>crypto.DEFAULT_ENCODING</code> mechanism is provided for backward compatibility 1757with legacy programs that expect <code>'latin1'</code> to be the default encoding.</p> 1758<p>New applications should expect the default to be <code>'buffer'</code>.</p> 1759<p>This property is deprecated.</p> 1760<h4><code>crypto.fips</code><span><a class="mark" href="#crypto_crypto_fips" id="crypto_crypto_fips">#</a></span></h4> 1761<div class="api_metadata"> 1762<span>Added in: v6.0.0</span><span>Deprecated since: v10.0.0</span> 1763</div> 1764<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated</div><p></p> 1765<p>Property for checking and controlling whether a FIPS compliant crypto provider 1766is currently in use. Setting to true requires a FIPS build of Node.js.</p> 1767<p>This property is deprecated. Please use <code>crypto.setFips()</code> and 1768<code>crypto.getFips()</code> instead.</p> 1769<h4><code>crypto.createCipher(algorithm, password[, options])</code><span><a class="mark" href="#crypto_crypto_createcipher_algorithm_password_options" id="crypto_crypto_createcipher_algorithm_password_options">#</a></span></h4> 1770<div class="api_metadata"> 1771<details class="changelog"><summary>History</summary> 1772<table> 1773<tbody><tr><th>Version</th><th>Changes</th></tr> 1774<tr><td>v10.10.0</td> 1775<td><p>Ciphers in OCB mode are now supported.</p></td></tr> 1776<tr><td>v10.2.0</td> 1777<td><p>The <code>authTagLength</code> option can now be used to produce shorter authentication tags in GCM mode and defaults to 16 bytes.</p></td></tr> 1778<tr><td>v10.0.0</td> 1779<td><p><span>Deprecated since: v10.0.0</span></p></td></tr> 1780<tr><td>v0.1.94</td> 1781<td><p><span>Added in: v0.1.94</span></p></td></tr> 1782</tbody></table> 1783</details> 1784</div> 1785<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated: Use <a href="#crypto_crypto_createcipheriv_algorithm_key_iv_options"><code>crypto.createCipheriv()</code></a> instead.</div><p></p> 1786<ul> 1787<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1788<li><code>password</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1789<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a></li> 1790<li>Returns: <a href="crypto.html#crypto_class_cipher" class="type"><Cipher></a></li> 1791</ul> 1792<p>Creates and returns a <code>Cipher</code> object that uses the given <code>algorithm</code> and 1793<code>password</code>.</p> 1794<p>The <code>options</code> argument controls stream behavior and is optional except when a 1795cipher in CCM or OCB mode is used (e.g. <code>'aes-128-ccm'</code>). In that case, the 1796<code>authTagLength</code> option is required and specifies the length of the 1797authentication tag in bytes, see <a href="#crypto_ccm_mode">CCM mode</a>. In GCM mode, the <code>authTagLength</code> 1798option is not required but can be used to set the length of the authentication 1799tag that will be returned by <code>getAuthTag()</code> and defaults to 16 bytes.</p> 1800<p>The <code>algorithm</code> is dependent on OpenSSL, examples are <code>'aes192'</code>, etc. On 1801recent OpenSSL releases, <code>openssl list -cipher-algorithms</code> 1802(<code>openssl list-cipher-algorithms</code> for older versions of OpenSSL) will 1803display the available cipher algorithms.</p> 1804<p>The <code>password</code> is used to derive the cipher key and initialization vector (IV). 1805The value must be either a <code>'latin1'</code> encoded string, a <a href="buffer.html"><code>Buffer</code></a>, a 1806<code>TypedArray</code>, or a <code>DataView</code>.</p> 1807<p>The implementation of <code>crypto.createCipher()</code> derives keys using the OpenSSL 1808function <a href="https://www.openssl.org/docs/man1.1.0/crypto/EVP_BytesToKey.html"><code>EVP_BytesToKey</code></a> with the digest algorithm set to MD5, one 1809iteration, and no salt. The lack of salt allows dictionary attacks as the same 1810password always creates the same key. The low iteration count and 1811non-cryptographically secure hash algorithm allow passwords to be tested very 1812rapidly.</p> 1813<p>In line with OpenSSL's recommendation to use a more modern algorithm instead of 1814<a href="https://www.openssl.org/docs/man1.1.0/crypto/EVP_BytesToKey.html"><code>EVP_BytesToKey</code></a> it is recommended that developers derive a key and IV on 1815their own using <a href="#crypto_crypto_scrypt_password_salt_keylen_options_callback"><code>crypto.scrypt()</code></a> and to use <a href="#crypto_crypto_createcipheriv_algorithm_key_iv_options"><code>crypto.createCipheriv()</code></a> 1816to create the <code>Cipher</code> object. Users should not use ciphers with counter mode 1817(e.g. CTR, GCM, or CCM) in <code>crypto.createCipher()</code>. A warning is emitted when 1818they are used in order to avoid the risk of IV reuse that causes 1819vulnerabilities. For the case when IV is reused in GCM, see <a href="https://github.com/nonce-disrespect/nonce-disrespect">Nonce-Disrespecting 1820Adversaries</a> for details.</p> 1821<h4><code>crypto.createCipheriv(algorithm, key, iv[, options])</code><span><a class="mark" href="#crypto_crypto_createcipheriv_algorithm_key_iv_options" id="crypto_crypto_createcipheriv_algorithm_key_iv_options">#</a></span></h4> 1822<div class="api_metadata"> 1823<details class="changelog"><summary>History</summary> 1824<table> 1825<tbody><tr><th>Version</th><th>Changes</th></tr> 1826<tr><td>v11.6.0</td> 1827<td><p>The <code>key</code> argument can now be a <code>KeyObject</code>.</p></td></tr> 1828<tr><td>v11.2.0, v10.17.0</td> 1829<td><p>The cipher <code>chacha20-poly1305</code> is now supported.</p></td></tr> 1830<tr><td>v10.10.0</td> 1831<td><p>Ciphers in OCB mode are now supported.</p></td></tr> 1832<tr><td>v10.2.0</td> 1833<td><p>The <code>authTagLength</code> option can now be used to produce shorter authentication tags in GCM mode and defaults to 16 bytes.</p></td></tr> 1834<tr><td>v9.9.0</td> 1835<td><p>The <code>iv</code> parameter may now be <code>null</code> for ciphers which do not need an initialization vector.</p></td></tr> 1836<tr><td>v0.1.94</td> 1837<td><p><span>Added in: v0.1.94</span></p></td></tr> 1838</tbody></table> 1839</details> 1840</div> 1841<ul> 1842<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1843<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 1844<li><code>iv</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Null_type" class="type"><null></a></li> 1845<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a></li> 1846<li>Returns: <a href="crypto.html#crypto_class_cipher" class="type"><Cipher></a></li> 1847</ul> 1848<p>Creates and returns a <code>Cipher</code> object, with the given <code>algorithm</code>, <code>key</code> and 1849initialization vector (<code>iv</code>).</p> 1850<p>The <code>options</code> argument controls stream behavior and is optional except when a 1851cipher in CCM or OCB mode is used (e.g. <code>'aes-128-ccm'</code>). In that case, the 1852<code>authTagLength</code> option is required and specifies the length of the 1853authentication tag in bytes, see <a href="#crypto_ccm_mode">CCM mode</a>. In GCM mode, the <code>authTagLength</code> 1854option is not required but can be used to set the length of the authentication 1855tag that will be returned by <code>getAuthTag()</code> and defaults to 16 bytes.</p> 1856<p>The <code>algorithm</code> is dependent on OpenSSL, examples are <code>'aes192'</code>, etc. On 1857recent OpenSSL releases, <code>openssl list -cipher-algorithms</code> 1858(<code>openssl list-cipher-algorithms</code> for older versions of OpenSSL) will 1859display the available cipher algorithms.</p> 1860<p>The <code>key</code> is the raw key used by the <code>algorithm</code> and <code>iv</code> is an 1861<a href="https://en.wikipedia.org/wiki/Initialization_vector">initialization vector</a>. Both arguments must be <code>'utf8'</code> encoded strings, 1862<a href="buffer.html">Buffers</a>, <code>TypedArray</code>, or <code>DataView</code>s. The <code>key</code> may optionally be 1863a <a href="#crypto_class_keyobject"><code>KeyObject</code></a> of type <code>secret</code>. If the cipher does not need 1864an initialization vector, <code>iv</code> may be <code>null</code>.</p> 1865<p>Initialization vectors should be unpredictable and unique; ideally, they will be 1866cryptographically random. They do not have to be secret: IVs are typically just 1867added to ciphertext messages unencrypted. It may sound contradictory that 1868something has to be unpredictable and unique, but does not have to be secret; 1869remember that an attacker must not be able to predict ahead of time what a 1870given IV will be.</p> 1871<h4><code>crypto.createDecipher(algorithm, password[, options])</code><span><a class="mark" href="#crypto_crypto_createdecipher_algorithm_password_options" id="crypto_crypto_createdecipher_algorithm_password_options">#</a></span></h4> 1872<div class="api_metadata"> 1873<details class="changelog"><summary>History</summary> 1874<table> 1875<tbody><tr><th>Version</th><th>Changes</th></tr> 1876<tr><td>v10.10.0</td> 1877<td><p>Ciphers in OCB mode are now supported.</p></td></tr> 1878<tr><td>v10.0.0</td> 1879<td><p><span>Deprecated since: v10.0.0</span></p></td></tr> 1880<tr><td>v0.1.94</td> 1881<td><p><span>Added in: v0.1.94</span></p></td></tr> 1882</tbody></table> 1883</details> 1884</div> 1885<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated: Use <a href="#crypto_crypto_createdecipheriv_algorithm_key_iv_options"><code>crypto.createDecipheriv()</code></a> instead.</div><p></p> 1886<ul> 1887<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1888<li><code>password</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1889<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a></li> 1890<li>Returns: <a href="crypto.html#crypto_class_decipher" class="type"><Decipher></a></li> 1891</ul> 1892<p>Creates and returns a <code>Decipher</code> object that uses the given <code>algorithm</code> and 1893<code>password</code> (key).</p> 1894<p>The <code>options</code> argument controls stream behavior and is optional except when a 1895cipher in CCM or OCB mode is used (e.g. <code>'aes-128-ccm'</code>). In that case, the 1896<code>authTagLength</code> option is required and specifies the length of the 1897authentication tag in bytes, see <a href="#crypto_ccm_mode">CCM mode</a>.</p> 1898<p>The implementation of <code>crypto.createDecipher()</code> derives keys using the OpenSSL 1899function <a href="https://www.openssl.org/docs/man1.1.0/crypto/EVP_BytesToKey.html"><code>EVP_BytesToKey</code></a> with the digest algorithm set to MD5, one 1900iteration, and no salt. The lack of salt allows dictionary attacks as the same 1901password always creates the same key. The low iteration count and 1902non-cryptographically secure hash algorithm allow passwords to be tested very 1903rapidly.</p> 1904<p>In line with OpenSSL's recommendation to use a more modern algorithm instead of 1905<a href="https://www.openssl.org/docs/man1.1.0/crypto/EVP_BytesToKey.html"><code>EVP_BytesToKey</code></a> it is recommended that developers derive a key and IV on 1906their own using <a href="#crypto_crypto_scrypt_password_salt_keylen_options_callback"><code>crypto.scrypt()</code></a> and to use <a href="#crypto_crypto_createdecipheriv_algorithm_key_iv_options"><code>crypto.createDecipheriv()</code></a> 1907to create the <code>Decipher</code> object.</p> 1908<h4><code>crypto.createDecipheriv(algorithm, key, iv[, options])</code><span><a class="mark" href="#crypto_crypto_createdecipheriv_algorithm_key_iv_options" id="crypto_crypto_createdecipheriv_algorithm_key_iv_options">#</a></span></h4> 1909<div class="api_metadata"> 1910<details class="changelog"><summary>History</summary> 1911<table> 1912<tbody><tr><th>Version</th><th>Changes</th></tr> 1913<tr><td>v11.6.0</td> 1914<td><p>The <code>key</code> argument can now be a <code>KeyObject</code>.</p></td></tr> 1915<tr><td>v11.2.0, v10.17.0</td> 1916<td><p>The cipher <code>chacha20-poly1305</code> is now supported.</p></td></tr> 1917<tr><td>v10.10.0</td> 1918<td><p>Ciphers in OCB mode are now supported.</p></td></tr> 1919<tr><td>v10.2.0</td> 1920<td><p>The <code>authTagLength</code> option can now be used to restrict accepted GCM authentication tag lengths.</p></td></tr> 1921<tr><td>v9.9.0</td> 1922<td><p>The <code>iv</code> parameter may now be <code>null</code> for ciphers which do not need an initialization vector.</p></td></tr> 1923<tr><td>v0.1.94</td> 1924<td><p><span>Added in: v0.1.94</span></p></td></tr> 1925</tbody></table> 1926</details> 1927</div> 1928<ul> 1929<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1930<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 1931<li><code>iv</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Null_type" class="type"><null></a></li> 1932<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a></li> 1933<li>Returns: <a href="crypto.html#crypto_class_decipher" class="type"><Decipher></a></li> 1934</ul> 1935<p>Creates and returns a <code>Decipher</code> object that uses the given <code>algorithm</code>, <code>key</code> 1936and initialization vector (<code>iv</code>).</p> 1937<p>The <code>options</code> argument controls stream behavior and is optional except when a 1938cipher in CCM or OCB mode is used (e.g. <code>'aes-128-ccm'</code>). In that case, the 1939<code>authTagLength</code> option is required and specifies the length of the 1940authentication tag in bytes, see <a href="#crypto_ccm_mode">CCM mode</a>. In GCM mode, the <code>authTagLength</code> 1941option is not required but can be used to restrict accepted authentication tags 1942to those with the specified length.</p> 1943<p>The <code>algorithm</code> is dependent on OpenSSL, examples are <code>'aes192'</code>, etc. On 1944recent OpenSSL releases, <code>openssl list -cipher-algorithms</code> 1945(<code>openssl list-cipher-algorithms</code> for older versions of OpenSSL) will 1946display the available cipher algorithms.</p> 1947<p>The <code>key</code> is the raw key used by the <code>algorithm</code> and <code>iv</code> is an 1948<a href="https://en.wikipedia.org/wiki/Initialization_vector">initialization vector</a>. Both arguments must be <code>'utf8'</code> encoded strings, 1949<a href="buffer.html">Buffers</a>, <code>TypedArray</code>, or <code>DataView</code>s. The <code>key</code> may optionally be 1950a <a href="#crypto_class_keyobject"><code>KeyObject</code></a> of type <code>secret</code>. If the cipher does not need 1951an initialization vector, <code>iv</code> may be <code>null</code>.</p> 1952<p>Initialization vectors should be unpredictable and unique; ideally, they will be 1953cryptographically random. They do not have to be secret: IVs are typically just 1954added to ciphertext messages unencrypted. It may sound contradictory that 1955something has to be unpredictable and unique, but does not have to be secret; 1956remember that an attacker must not be able to predict ahead of time what a given 1957IV will be.</p> 1958<h4><code>crypto.createDiffieHellman(prime[, primeEncoding][, generator][, generatorEncoding])</code><span><a class="mark" href="#crypto_crypto_creatediffiehellman_prime_primeencoding_generator_generatorencoding" id="crypto_crypto_creatediffiehellman_prime_primeencoding_generator_generatorencoding">#</a></span></h4> 1959<div class="api_metadata"> 1960<details class="changelog"><summary>History</summary> 1961<table> 1962<tbody><tr><th>Version</th><th>Changes</th></tr> 1963<tr><td>v8.0.0</td> 1964<td><p>The <code>prime</code> argument can be any <code>TypedArray</code> or <code>DataView</code> now.</p></td></tr> 1965<tr><td>v8.0.0</td> 1966<td><p>The <code>prime</code> argument can be a <code>Uint8Array</code> now.</p></td></tr> 1967<tr><td>v6.0.0</td> 1968<td><p>The default for the encoding parameters changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 1969<tr><td>v0.11.12</td> 1970<td><p><span>Added in: v0.11.12</span></p></td></tr> 1971</tbody></table> 1972</details> 1973</div> 1974<ul> 1975<li><code>prime</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 1976<li><code>primeEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>prime</code> string.</li> 1977<li><code>generator</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> <strong>Default:</strong> 1978<code>2</code></li> 1979<li><code>generatorEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The <a href="buffer.html#buffer_buffers_and_character_encodings">encoding</a> of the <code>generator</code> string.</li> 1980<li>Returns: <a href="crypto.html#crypto_class_diffiehellman" class="type"><DiffieHellman></a></li> 1981</ul> 1982<p>Creates a <code>DiffieHellman</code> key exchange object using the supplied <code>prime</code> and an 1983optional specific <code>generator</code>.</p> 1984<p>The <code>generator</code> argument can be a number, string, or <a href="buffer.html"><code>Buffer</code></a>. If 1985<code>generator</code> is not specified, the value <code>2</code> is used.</p> 1986<p>If <code>primeEncoding</code> is specified, <code>prime</code> is expected to be a string; otherwise 1987a <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or <code>DataView</code> is expected.</p> 1988<p>If <code>generatorEncoding</code> is specified, <code>generator</code> is expected to be a string; 1989otherwise a number, <a href="buffer.html"><code>Buffer</code></a>, <code>TypedArray</code>, or <code>DataView</code> is expected.</p> 1990<h4><code>crypto.createDiffieHellman(primeLength[, generator])</code><span><a class="mark" href="#crypto_crypto_creatediffiehellman_primelength_generator" id="crypto_crypto_creatediffiehellman_primelength_generator">#</a></span></h4> 1991<div class="api_metadata"> 1992<span>Added in: v0.5.0</span> 1993</div> 1994<ul> 1995<li><code>primeLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 1996<li><code>generator</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> <strong>Default:</strong> <code>2</code></li> 1997<li>Returns: <a href="crypto.html#crypto_class_diffiehellman" class="type"><DiffieHellman></a></li> 1998</ul> 1999<p>Creates a <code>DiffieHellman</code> key exchange object and generates a prime of 2000<code>primeLength</code> bits using an optional specific numeric <code>generator</code>. 2001If <code>generator</code> is not specified, the value <code>2</code> is used.</p> 2002<h4><code>crypto.createDiffieHellmanGroup(name)</code><span><a class="mark" href="#crypto_crypto_creatediffiehellmangroup_name" id="crypto_crypto_creatediffiehellmangroup_name">#</a></span></h4> 2003<div class="api_metadata"> 2004<span>Added in: v0.9.3</span> 2005</div> 2006<ul> 2007<li><code>name</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2008<li>Returns: <a href="crypto.html#crypto_class_diffiehellmangroup" class="type"><DiffieHellmanGroup></a></li> 2009</ul> 2010<p>An alias for <a href="#crypto_crypto_getdiffiehellman_groupname"><code>crypto.getDiffieHellman()</code></a></p> 2011<h4><code>crypto.createECDH(curveName)</code><span><a class="mark" href="#crypto_crypto_createecdh_curvename" id="crypto_crypto_createecdh_curvename">#</a></span></h4> 2012<div class="api_metadata"> 2013<span>Added in: v0.11.14</span> 2014</div> 2015<ul> 2016<li><code>curveName</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2017<li>Returns: <a href="crypto.html#crypto_class_ecdh" class="type"><ECDH></a></li> 2018</ul> 2019<p>Creates an Elliptic Curve Diffie-Hellman (<code>ECDH</code>) key exchange object using a 2020predefined curve specified by the <code>curveName</code> string. Use 2021<a href="#crypto_crypto_getcurves"><code>crypto.getCurves()</code></a> to obtain a list of available curve names. On recent 2022OpenSSL releases, <code>openssl ecparam -list_curves</code> will also display the name 2023and description of each available elliptic curve.</p> 2024<h4><code>crypto.createHash(algorithm[, options])</code><span><a class="mark" href="#crypto_crypto_createhash_algorithm_options" id="crypto_crypto_createhash_algorithm_options">#</a></span></h4> 2025<div class="api_metadata"> 2026<details class="changelog"><summary>History</summary> 2027<table> 2028<tbody><tr><th>Version</th><th>Changes</th></tr> 2029<tr><td>v12.8.0</td> 2030<td><p>The <code>outputLength</code> option was added for XOF hash functions.</p></td></tr> 2031<tr><td>v0.1.92</td> 2032<td><p><span>Added in: v0.1.92</span></p></td></tr> 2033</tbody></table> 2034</details> 2035</div> 2036<ul> 2037<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2038<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a></li> 2039<li>Returns: <a href="crypto.html#crypto_class_hash" class="type"><Hash></a></li> 2040</ul> 2041<p>Creates and returns a <code>Hash</code> object that can be used to generate hash digests 2042using the given <code>algorithm</code>. Optional <code>options</code> argument controls stream 2043behavior. For XOF hash functions such as <code>'shake256'</code>, the <code>outputLength</code> option 2044can be used to specify the desired output length in bytes.</p> 2045<p>The <code>algorithm</code> is dependent on the available algorithms supported by the 2046version of OpenSSL on the platform. Examples are <code>'sha256'</code>, <code>'sha512'</code>, etc. 2047On recent releases of OpenSSL, <code>openssl list -digest-algorithms</code> 2048(<code>openssl list-message-digest-algorithms</code> for older versions of OpenSSL) will 2049display the available digest algorithms.</p> 2050<p>Example: generating the sha256 sum of a file</p> 2051<pre><code class="language-js"><span class="hljs-keyword">const</span> filename = process.<span class="hljs-property">argv</span>[<span class="hljs-number">2</span>]; 2052<span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2053<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 2054 2055<span class="hljs-keyword">const</span> hash = crypto.<span class="hljs-title function_">createHash</span>(<span class="hljs-string">'sha256'</span>); 2056 2057<span class="hljs-keyword">const</span> input = fs.<span class="hljs-title function_">createReadStream</span>(filename); 2058input.<span class="hljs-title function_">on</span>(<span class="hljs-string">'readable'</span>, <span class="hljs-function">() =></span> { 2059 <span class="hljs-comment">// Only one element is going to be produced by the</span> 2060 <span class="hljs-comment">// hash stream.</span> 2061 <span class="hljs-keyword">const</span> data = input.<span class="hljs-title function_">read</span>(); 2062 <span class="hljs-keyword">if</span> (data) 2063 hash.<span class="hljs-title function_">update</span>(data); 2064 <span class="hljs-keyword">else</span> { 2065 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`<span class="hljs-subst">${hash.digest(<span class="hljs-string">'hex'</span>)}</span> <span class="hljs-subst">${filename}</span>`</span>); 2066 } 2067});</code></pre> 2068<h4><code>crypto.createHmac(algorithm, key[, options])</code><span><a class="mark" href="#crypto_crypto_createhmac_algorithm_key_options" id="crypto_crypto_createhmac_algorithm_key_options">#</a></span></h4> 2069<div class="api_metadata"> 2070<details class="changelog"><summary>History</summary> 2071<table> 2072<tbody><tr><th>Version</th><th>Changes</th></tr> 2073<tr><td>v11.6.0</td> 2074<td><p>The <code>key</code> argument can now be a <code>KeyObject</code>.</p></td></tr> 2075<tr><td>v0.1.94</td> 2076<td><p><span>Added in: v0.1.94</span></p></td></tr> 2077</tbody></table> 2078</details> 2079</div> 2080<ul> 2081<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2082<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2083<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_transform_options"><code>stream.transform</code> options</a></li> 2084<li>Returns: <a href="crypto.html#crypto_class_hmac" class="type"><Hmac></a></li> 2085</ul> 2086<p>Creates and returns an <code>Hmac</code> object that uses the given <code>algorithm</code> and <code>key</code>. 2087Optional <code>options</code> argument controls stream behavior.</p> 2088<p>The <code>algorithm</code> is dependent on the available algorithms supported by the 2089version of OpenSSL on the platform. Examples are <code>'sha256'</code>, <code>'sha512'</code>, etc. 2090On recent releases of OpenSSL, <code>openssl list -digest-algorithms</code> 2091(<code>openssl list-message-digest-algorithms</code> for older versions of OpenSSL) will 2092display the available digest algorithms.</p> 2093<p>The <code>key</code> is the HMAC key used to generate the cryptographic HMAC hash. If it is 2094a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, its type must be <code>secret</code>.</p> 2095<p>Example: generating the sha256 HMAC of a file</p> 2096<pre><code class="language-js"><span class="hljs-keyword">const</span> filename = process.<span class="hljs-property">argv</span>[<span class="hljs-number">2</span>]; 2097<span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2098<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 2099 2100<span class="hljs-keyword">const</span> hmac = crypto.<span class="hljs-title function_">createHmac</span>(<span class="hljs-string">'sha256'</span>, <span class="hljs-string">'a secret'</span>); 2101 2102<span class="hljs-keyword">const</span> input = fs.<span class="hljs-title function_">createReadStream</span>(filename); 2103input.<span class="hljs-title function_">on</span>(<span class="hljs-string">'readable'</span>, <span class="hljs-function">() =></span> { 2104 <span class="hljs-comment">// Only one element is going to be produced by the</span> 2105 <span class="hljs-comment">// hash stream.</span> 2106 <span class="hljs-keyword">const</span> data = input.<span class="hljs-title function_">read</span>(); 2107 <span class="hljs-keyword">if</span> (data) 2108 hmac.<span class="hljs-title function_">update</span>(data); 2109 <span class="hljs-keyword">else</span> { 2110 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`<span class="hljs-subst">${hmac.digest(<span class="hljs-string">'hex'</span>)}</span> <span class="hljs-subst">${filename}</span>`</span>); 2111 } 2112});</code></pre> 2113<h4><code>crypto.createPrivateKey(key)</code><span><a class="mark" href="#crypto_crypto_createprivatekey_key" id="crypto_crypto_createprivatekey_key">#</a></span></h4> 2114<div class="api_metadata"> 2115<span>Added in: v11.6.0</span> 2116</div> 2117<ul> 2118<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> 2119<ul> 2120<li><code>key</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The key material, either in PEM or DER format.</li> 2121<li><code>format</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'pem'</code> or <code>'der'</code>. <strong>Default:</strong> <code>'pem'</code>.</li> 2122<li><code>type</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'pkcs1'</code>, <code>'pkcs8'</code> or <code>'sec1'</code>. This option is 2123required only if the <code>format</code> is <code>'der'</code> and ignored if it is <code>'pem'</code>.</li> 2124<li><code>passphrase</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The passphrase to use for decryption.</li> 2125</ul> 2126</li> 2127<li>Returns: <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2128</ul> 2129<p>Creates and returns a new key object containing a private key. If <code>key</code> is a 2130string or <code>Buffer</code>, <code>format</code> is assumed to be <code>'pem'</code>; otherwise, <code>key</code> 2131must be an object with the properties described above.</p> 2132<p>If the private key is encrypted, a <code>passphrase</code> must be specified. The length 2133of the passphrase is limited to 1024 bytes.</p> 2134<h4><code>crypto.createPublicKey(key)</code><span><a class="mark" href="#crypto_crypto_createpublickey_key" id="crypto_crypto_createpublickey_key">#</a></span></h4> 2135<div class="api_metadata"> 2136<details class="changelog"><summary>History</summary> 2137<table> 2138<tbody><tr><th>Version</th><th>Changes</th></tr> 2139<tr><td>v11.13.0</td> 2140<td><p>The <code>key</code> argument can now be a <code>KeyObject</code> with type <code>private</code>.</p></td></tr> 2141<tr><td>v11.7.0</td> 2142<td><p>The <code>key</code> argument can now be a private key.</p></td></tr> 2143<tr><td>v11.6.0</td> 2144<td><p><span>Added in: v11.6.0</span></p></td></tr> 2145</tbody></table> 2146</details> 2147</div> 2148<ul> 2149<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> 2150<ul> 2151<li><code>key</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 2152<li><code>format</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'pem'</code> or <code>'der'</code>. <strong>Default:</strong> <code>'pem'</code>.</li> 2153<li><code>type</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'pkcs1'</code> or <code>'spki'</code>. This option is required 2154only if the <code>format</code> is <code>'der'</code>.</li> 2155</ul> 2156</li> 2157<li>Returns: <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2158</ul> 2159<p>Creates and returns a new key object containing a public key. If <code>key</code> is a 2160string or <code>Buffer</code>, <code>format</code> is assumed to be <code>'pem'</code>; if <code>key</code> is a <code>KeyObject</code> 2161with type <code>'private'</code>, the public key is derived from the given private key; 2162otherwise, <code>key</code> must be an object with the properties described above.</p> 2163<p>If the format is <code>'pem'</code>, the <code>'key'</code> may also be an X.509 certificate.</p> 2164<p>Because public keys can be derived from private keys, a private key may be 2165passed instead of a public key. In that case, this function behaves as if 2166<a href="#crypto_crypto_createprivatekey_key"><code>crypto.createPrivateKey()</code></a> had been called, except that the type of the 2167returned <code>KeyObject</code> will be <code>'public'</code> and that the private key cannot be 2168extracted from the returned <code>KeyObject</code>. Similarly, if a <code>KeyObject</code> with type 2169<code>'private'</code> is given, a new <code>KeyObject</code> with type <code>'public'</code> will be returned 2170and it will be impossible to extract the private key from the returned object.</p> 2171<h4><code>crypto.createSecretKey(key)</code><span><a class="mark" href="#crypto_crypto_createsecretkey_key" id="crypto_crypto_createsecretkey_key">#</a></span></h4> 2172<div class="api_metadata"> 2173<span>Added in: v11.6.0</span> 2174</div> 2175<ul> 2176<li><code>key</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2177<li>Returns: <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2178</ul> 2179<p>Creates and returns a new key object containing a secret key for symmetric 2180encryption or <code>Hmac</code>.</p> 2181<h4><code>crypto.createSign(algorithm[, options])</code><span><a class="mark" href="#crypto_crypto_createsign_algorithm_options" id="crypto_crypto_createsign_algorithm_options">#</a></span></h4> 2182<div class="api_metadata"> 2183<span>Added in: v0.1.92</span> 2184</div> 2185<ul> 2186<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2187<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_writable_options"><code>stream.Writable</code> options</a></li> 2188<li>Returns: <a href="crypto.html#crypto_class_sign" class="type"><Sign></a></li> 2189</ul> 2190<p>Creates and returns a <code>Sign</code> object that uses the given <code>algorithm</code>. Use 2191<a href="#crypto_crypto_gethashes"><code>crypto.getHashes()</code></a> to obtain the names of the available digest algorithms. 2192Optional <code>options</code> argument controls the <code>stream.Writable</code> behavior.</p> 2193<p>In some cases, a <code>Sign</code> instance can be created using the name of a signature 2194algorithm, such as <code>'RSA-SHA256'</code>, instead of a digest algorithm. This will use 2195the corresponding digest algorithm. This does not work for all signature 2196algorithms, such as <code>'ecdsa-with-SHA256'</code>, so it is best to always use digest 2197algorithm names.</p> 2198<h4><code>crypto.createVerify(algorithm[, options])</code><span><a class="mark" href="#crypto_crypto_createverify_algorithm_options" id="crypto_crypto_createverify_algorithm_options">#</a></span></h4> 2199<div class="api_metadata"> 2200<span>Added in: v0.1.92</span> 2201</div> 2202<ul> 2203<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2204<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> <a href="stream.html#stream_new_stream_writable_options"><code>stream.Writable</code> options</a></li> 2205<li>Returns: <a href="crypto.html#crypto_class_verify" class="type"><Verify></a></li> 2206</ul> 2207<p>Creates and returns a <code>Verify</code> object that uses the given algorithm. 2208Use <a href="#crypto_crypto_gethashes"><code>crypto.getHashes()</code></a> to obtain an array of names of the available 2209signing algorithms. Optional <code>options</code> argument controls the 2210<code>stream.Writable</code> behavior.</p> 2211<p>In some cases, a <code>Verify</code> instance can be created using the name of a signature 2212algorithm, such as <code>'RSA-SHA256'</code>, instead of a digest algorithm. This will use 2213the corresponding digest algorithm. This does not work for all signature 2214algorithms, such as <code>'ecdsa-with-SHA256'</code>, so it is best to always use digest 2215algorithm names.</p> 2216<h4><code>crypto.diffieHellman(options)</code><span><a class="mark" href="#crypto_crypto_diffiehellman_options" id="crypto_crypto_diffiehellman_options">#</a></span></h4> 2217<div class="api_metadata"> 2218<span>Added in: v13.9.0</span> 2219</div> 2220<ul> 2221<li><code>options</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 2222<ul> 2223<li><code>privateKey</code>: <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2224<li><code>publicKey</code>: <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2225</ul> 2226</li> 2227<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 2228</ul> 2229<p>Computes the Diffie-Hellman secret based on a <code>privateKey</code> and a <code>publicKey</code>. 2230Both keys must have the same <code>asymmetricKeyType</code>, which must be one of <code>'dh'</code> 2231(for Diffie-Hellman), <code>'ec'</code> (for ECDH), <code>'x448'</code>, or <code>'x25519'</code> (for ECDH-ES).</p> 2232<h4><code>crypto.generateKeyPair(type, options, callback)</code><span><a class="mark" href="#crypto_crypto_generatekeypair_type_options_callback" id="crypto_crypto_generatekeypair_type_options_callback">#</a></span></h4> 2233<div class="api_metadata"> 2234<details class="changelog"><summary>History</summary> 2235<table> 2236<tbody><tr><th>Version</th><th>Changes</th></tr> 2237<tr><td>v13.9.0</td> 2238<td><p>Add support for Diffie-Hellman.</p></td></tr> 2239<tr><td>v12.0.0</td> 2240<td><p>Add ability to generate X25519 and X448 key pairs.</p></td></tr> 2241<tr><td>v12.0.0</td> 2242<td><p>Add ability to generate Ed25519 and Ed448 key pairs.</p></td></tr> 2243<tr><td>v11.6.0</td> 2244<td><p>The <code>generateKeyPair</code> and <code>generateKeyPairSync</code> functions now produce key objects if no encoding was specified.</p></td></tr> 2245<tr><td>v10.12.0</td> 2246<td><p><span>Added in: v10.12.0</span></p></td></tr> 2247</tbody></table> 2248</details> 2249</div> 2250<ul> 2251<li><code>type</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'rsa'</code>, <code>'dsa'</code>, <code>'ec'</code>, <code>'ed25519'</code>, <code>'ed448'</code>, 2252<code>'x25519'</code>, <code>'x448'</code>, or <code>'dh'</code>.</li> 2253<li><code>options</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 2254<ul> 2255<li><code>modulusLength</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Key size in bits (RSA, DSA).</li> 2256<li><code>publicExponent</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Public exponent (RSA). <strong>Default:</strong> <code>0x10001</code>.</li> 2257<li><code>divisorLength</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Size of <code>q</code> in bits (DSA).</li> 2258<li><code>namedCurve</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Name of the curve to use (EC).</li> 2259<li><code>prime</code>: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The prime parameter (DH).</li> 2260<li><code>primeLength</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Prime length in bits (DH).</li> 2261<li><code>generator</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Custom generator (DH). <strong>Default:</strong> <code>2</code>.</li> 2262<li><code>groupName</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Diffie-Hellman group name (DH). See 2263<a href="#crypto_crypto_getdiffiehellman_groupname"><code>crypto.getDiffieHellman()</code></a>.</li> 2264<li><code>publicKeyEncoding</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> See <a href="#crypto_keyobject_export_options"><code>keyObject.export()</code></a>.</li> 2265<li><code>privateKeyEncoding</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> See <a href="#crypto_keyobject_export_options"><code>keyObject.export()</code></a>.</li> 2266</ul> 2267</li> 2268<li><code>callback</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 2269<ul> 2270<li><code>err</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a></li> 2271<li><code>publicKey</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2272<li><code>privateKey</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2273</ul> 2274</li> 2275</ul> 2276<p>Generates a new asymmetric key pair of the given <code>type</code>. RSA, DSA, EC, Ed25519, 2277Ed448, X25519, X448, and DH are currently supported.</p> 2278<p>If a <code>publicKeyEncoding</code> or <code>privateKeyEncoding</code> was specified, this function 2279behaves as if <a href="#crypto_keyobject_export_options"><code>keyObject.export()</code></a> had been called on its result. Otherwise, 2280the respective part of the key is returned as a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>.</p> 2281<p>It is recommended to encode public keys as <code>'spki'</code> and private keys as 2282<code>'pkcs8'</code> with encryption for long-term storage:</p> 2283<pre><code class="language-js"><span class="hljs-keyword">const</span> { generateKeyPair } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2284<span class="hljs-title function_">generateKeyPair</span>(<span class="hljs-string">'rsa'</span>, { 2285 <span class="hljs-attr">modulusLength</span>: <span class="hljs-number">4096</span>, 2286 <span class="hljs-attr">publicKeyEncoding</span>: { 2287 <span class="hljs-attr">type</span>: <span class="hljs-string">'spki'</span>, 2288 <span class="hljs-attr">format</span>: <span class="hljs-string">'pem'</span> 2289 }, 2290 <span class="hljs-attr">privateKeyEncoding</span>: { 2291 <span class="hljs-attr">type</span>: <span class="hljs-string">'pkcs8'</span>, 2292 <span class="hljs-attr">format</span>: <span class="hljs-string">'pem'</span>, 2293 <span class="hljs-attr">cipher</span>: <span class="hljs-string">'aes-256-cbc'</span>, 2294 <span class="hljs-attr">passphrase</span>: <span class="hljs-string">'top secret'</span> 2295 } 2296}, <span class="hljs-function">(<span class="hljs-params">err, publicKey, privateKey</span>) =></span> { 2297 <span class="hljs-comment">// Handle errors and use the generated key pair.</span> 2298});</code></pre> 2299<p>On completion, <code>callback</code> will be called with <code>err</code> set to <code>undefined</code> and 2300<code>publicKey</code> / <code>privateKey</code> representing the generated key pair.</p> 2301<p>If this method is invoked as its <a href="util.html#util_util_promisify_original"><code>util.promisify()</code></a>ed version, it returns 2302a <code>Promise</code> for an <code>Object</code> with <code>publicKey</code> and <code>privateKey</code> properties.</p> 2303<h4><code>crypto.generateKeyPairSync(type, options)</code><span><a class="mark" href="#crypto_crypto_generatekeypairsync_type_options" id="crypto_crypto_generatekeypairsync_type_options">#</a></span></h4> 2304<div class="api_metadata"> 2305<details class="changelog"><summary>History</summary> 2306<table> 2307<tbody><tr><th>Version</th><th>Changes</th></tr> 2308<tr><td>v13.9.0</td> 2309<td><p>Add support for Diffie-Hellman.</p></td></tr> 2310<tr><td>v12.0.0</td> 2311<td><p>Add ability to generate Ed25519 and Ed448 key pairs.</p></td></tr> 2312<tr><td>v11.6.0</td> 2313<td><p>The <code>generateKeyPair</code> and <code>generateKeyPairSync</code> functions now produce key objects if no encoding was specified.</p></td></tr> 2314<tr><td>v10.12.0</td> 2315<td><p><span>Added in: v10.12.0</span></p></td></tr> 2316</tbody></table> 2317</details> 2318</div> 2319<ul> 2320<li><code>type</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Must be <code>'rsa'</code>, <code>'dsa'</code>, <code>'ec'</code>, <code>'ed25519'</code>, <code>'ed448'</code>, 2321<code>'x25519'</code>, <code>'x448'</code>, or <code>'dh'</code>.</li> 2322<li><code>options</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 2323<ul> 2324<li><code>modulusLength</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Key size in bits (RSA, DSA).</li> 2325<li><code>publicExponent</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Public exponent (RSA). <strong>Default:</strong> <code>0x10001</code>.</li> 2326<li><code>divisorLength</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Size of <code>q</code> in bits (DSA).</li> 2327<li><code>namedCurve</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Name of the curve to use (EC).</li> 2328<li><code>prime</code>: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The prime parameter (DH).</li> 2329<li><code>primeLength</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Prime length in bits (DH).</li> 2330<li><code>generator</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Custom generator (DH). <strong>Default:</strong> <code>2</code>.</li> 2331<li><code>groupName</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Diffie-Hellman group name (DH). See 2332<a href="#crypto_crypto_getdiffiehellman_groupname"><code>crypto.getDiffieHellman()</code></a>.</li> 2333<li><code>publicKeyEncoding</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> See <a href="#crypto_keyobject_export_options"><code>keyObject.export()</code></a>.</li> 2334<li><code>privateKeyEncoding</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> See <a href="#crypto_keyobject_export_options"><code>keyObject.export()</code></a>.</li> 2335</ul> 2336</li> 2337<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 2338<ul> 2339<li><code>publicKey</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2340<li><code>privateKey</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 2341</ul> 2342</li> 2343</ul> 2344<p>Generates a new asymmetric key pair of the given <code>type</code>. RSA, DSA, EC, Ed25519, 2345Ed448, X25519, X448, and DH are currently supported.</p> 2346<p>If a <code>publicKeyEncoding</code> or <code>privateKeyEncoding</code> was specified, this function 2347behaves as if <a href="#crypto_keyobject_export_options"><code>keyObject.export()</code></a> had been called on its result. Otherwise, 2348the respective part of the key is returned as a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>.</p> 2349<p>When encoding public keys, it is recommended to use <code>'spki'</code>. When encoding 2350private keys, it is recommended to use <code>'pkcs8'</code> with a strong passphrase, 2351and to keep the passphrase confidential.</p> 2352<pre><code class="language-js"><span class="hljs-keyword">const</span> { generateKeyPairSync } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2353<span class="hljs-keyword">const</span> { publicKey, privateKey } = <span class="hljs-title function_">generateKeyPairSync</span>(<span class="hljs-string">'rsa'</span>, { 2354 <span class="hljs-attr">modulusLength</span>: <span class="hljs-number">4096</span>, 2355 <span class="hljs-attr">publicKeyEncoding</span>: { 2356 <span class="hljs-attr">type</span>: <span class="hljs-string">'spki'</span>, 2357 <span class="hljs-attr">format</span>: <span class="hljs-string">'pem'</span> 2358 }, 2359 <span class="hljs-attr">privateKeyEncoding</span>: { 2360 <span class="hljs-attr">type</span>: <span class="hljs-string">'pkcs8'</span>, 2361 <span class="hljs-attr">format</span>: <span class="hljs-string">'pem'</span>, 2362 <span class="hljs-attr">cipher</span>: <span class="hljs-string">'aes-256-cbc'</span>, 2363 <span class="hljs-attr">passphrase</span>: <span class="hljs-string">'top secret'</span> 2364 } 2365});</code></pre> 2366<p>The return value <code>{ publicKey, privateKey }</code> represents the generated key pair. 2367When PEM encoding was selected, the respective key will be a string, otherwise 2368it will be a buffer containing the data encoded as DER.</p> 2369<h4><code>crypto.getCiphers()</code><span><a class="mark" href="#crypto_crypto_getciphers" id="crypto_crypto_getciphers">#</a></span></h4> 2370<div class="api_metadata"> 2371<span>Added in: v0.9.3</span> 2372</div> 2373<ul> 2374<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a> An array with the names of the supported cipher 2375algorithms.</li> 2376</ul> 2377<pre><code class="language-js"><span class="hljs-keyword">const</span> ciphers = crypto.<span class="hljs-title function_">getCiphers</span>(); 2378<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(ciphers); <span class="hljs-comment">// ['aes-128-cbc', 'aes-128-ccm', ...]</span></code></pre> 2379<h4><code>crypto.getCurves()</code><span><a class="mark" href="#crypto_crypto_getcurves" id="crypto_crypto_getcurves">#</a></span></h4> 2380<div class="api_metadata"> 2381<span>Added in: v2.3.0</span> 2382</div> 2383<ul> 2384<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a> An array with the names of the supported elliptic curves.</li> 2385</ul> 2386<pre><code class="language-js"><span class="hljs-keyword">const</span> curves = crypto.<span class="hljs-title function_">getCurves</span>(); 2387<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(curves); <span class="hljs-comment">// ['Oakley-EC2N-3', 'Oakley-EC2N-4', ...]</span></code></pre> 2388<h4><code>crypto.getDiffieHellman(groupName)</code><span><a class="mark" href="#crypto_crypto_getdiffiehellman_groupname" id="crypto_crypto_getdiffiehellman_groupname">#</a></span></h4> 2389<div class="api_metadata"> 2390<span>Added in: v0.7.5</span> 2391</div> 2392<ul> 2393<li><code>groupName</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2394<li>Returns: <a href="crypto.html#crypto_class_diffiehellmangroup" class="type"><DiffieHellmanGroup></a></li> 2395</ul> 2396<p>Creates a predefined <code>DiffieHellmanGroup</code> key exchange object. The 2397supported groups are: <code>'modp1'</code>, <code>'modp2'</code>, <code>'modp5'</code> (defined in 2398<a href="https://www.rfc-editor.org/rfc/rfc2412.txt">RFC 2412</a>, but see <a href="#crypto_support_for_weak_or_compromised_algorithms">Caveats</a>) and <code>'modp14'</code>, <code>'modp15'</code>, 2399<code>'modp16'</code>, <code>'modp17'</code>, <code>'modp18'</code> (defined in <a href="https://www.rfc-editor.org/rfc/rfc3526.txt">RFC 3526</a>). The 2400returned object mimics the interface of objects created by 2401<a href="#crypto_crypto_creatediffiehellman_prime_primeencoding_generator_generatorencoding"><code>crypto.createDiffieHellman()</code></a>, but will not allow changing 2402the keys (with <a href="#crypto_diffiehellman_setpublickey_publickey_encoding"><code>diffieHellman.setPublicKey()</code></a>, for example). The 2403advantage of using this method is that the parties do not have to 2404generate nor exchange a group modulus beforehand, saving both processor 2405and communication time.</p> 2406<p>Example (obtaining a shared secret):</p> 2407<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2408<span class="hljs-keyword">const</span> alice = crypto.<span class="hljs-title function_">getDiffieHellman</span>(<span class="hljs-string">'modp14'</span>); 2409<span class="hljs-keyword">const</span> bob = crypto.<span class="hljs-title function_">getDiffieHellman</span>(<span class="hljs-string">'modp14'</span>); 2410 2411alice.<span class="hljs-title function_">generateKeys</span>(); 2412bob.<span class="hljs-title function_">generateKeys</span>(); 2413 2414<span class="hljs-keyword">const</span> aliceSecret = alice.<span class="hljs-title function_">computeSecret</span>(bob.<span class="hljs-title function_">getPublicKey</span>(), <span class="hljs-literal">null</span>, <span class="hljs-string">'hex'</span>); 2415<span class="hljs-keyword">const</span> bobSecret = bob.<span class="hljs-title function_">computeSecret</span>(alice.<span class="hljs-title function_">getPublicKey</span>(), <span class="hljs-literal">null</span>, <span class="hljs-string">'hex'</span>); 2416 2417<span class="hljs-comment">/* aliceSecret and bobSecret should be the same */</span> 2418<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(aliceSecret === bobSecret);</code></pre> 2419<h4><code>crypto.getFips()</code><span><a class="mark" href="#crypto_crypto_getfips" id="crypto_crypto_getfips">#</a></span></h4> 2420<div class="api_metadata"> 2421<span>Added in: v10.0.0</span> 2422</div> 2423<ul> 2424<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> <code>1</code> if and only if a FIPS compliant crypto provider is 2425currently in use, <code>0</code> otherwise. A future semver-major release may change 2426the return type of this API to a <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a>.</li> 2427</ul> 2428<h4><code>crypto.getHashes()</code><span><a class="mark" href="#crypto_crypto_gethashes" id="crypto_crypto_gethashes">#</a></span></h4> 2429<div class="api_metadata"> 2430<span>Added in: v0.9.3</span> 2431</div> 2432<ul> 2433<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a> An array of the names of the supported hash algorithms, 2434such as <code>'RSA-SHA256'</code>. Hash algorithms are also called "digest" algorithms.</li> 2435</ul> 2436<pre><code class="language-js"><span class="hljs-keyword">const</span> hashes = crypto.<span class="hljs-title function_">getHashes</span>(); 2437<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(hashes); <span class="hljs-comment">// ['DSA', 'DSA-SHA', 'DSA-SHA1', ...]</span></code></pre> 2438<h4><code>crypto.pbkdf2(password, salt, iterations, keylen, digest, callback)</code><span><a class="mark" href="#crypto_crypto_pbkdf2_password_salt_iterations_keylen_digest_callback" id="crypto_crypto_pbkdf2_password_salt_iterations_keylen_digest_callback">#</a></span></h4> 2439<div class="api_metadata"> 2440<details class="changelog"><summary>History</summary> 2441<table> 2442<tbody><tr><th>Version</th><th>Changes</th></tr> 2443<tr><td>v14.0.0</td> 2444<td><p>The <code>iterations</code> parameter is now restricted to positive values. Earlier releases treated other values as one.</p></td></tr> 2445<tr><td>v8.0.0</td> 2446<td><p>The <code>digest</code> parameter is always required now.</p></td></tr> 2447<tr><td>v6.0.0</td> 2448<td><p>Calling this function without passing the <code>digest</code> parameter is deprecated now and will emit a warning.</p></td></tr> 2449<tr><td>v6.0.0</td> 2450<td><p>The default encoding for <code>password</code> if it is a string changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 2451<tr><td>v0.5.5</td> 2452<td><p><span>Added in: v0.5.5</span></p></td></tr> 2453</tbody></table> 2454</details> 2455</div> 2456<ul> 2457<li><code>password</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2458<li><code>salt</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2459<li><code>iterations</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 2460<li><code>keylen</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 2461<li><code>digest</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2462<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 2463<ul> 2464<li><code>err</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a></li> 2465<li><code>derivedKey</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 2466</ul> 2467</li> 2468</ul> 2469<p>Provides an asynchronous Password-Based Key Derivation Function 2 (PBKDF2) 2470implementation. A selected HMAC digest algorithm specified by <code>digest</code> is 2471applied to derive a key of the requested byte length (<code>keylen</code>) from the 2472<code>password</code>, <code>salt</code> and <code>iterations</code>.</p> 2473<p>The supplied <code>callback</code> function is called with two arguments: <code>err</code> and 2474<code>derivedKey</code>. If an error occurs while deriving the key, <code>err</code> will be set; 2475otherwise <code>err</code> will be <code>null</code>. By default, the successfully generated 2476<code>derivedKey</code> will be passed to the callback as a <a href="buffer.html"><code>Buffer</code></a>. An error will be 2477thrown if any of the input arguments specify invalid values or types.</p> 2478<p>If <code>digest</code> is <code>null</code>, <code>'sha1'</code> will be used. This behavior is deprecated, 2479please specify a <code>digest</code> explicitly.</p> 2480<p>The <code>iterations</code> argument must be a number set as high as possible. The 2481higher the number of iterations, the more secure the derived key will be, 2482but will take a longer amount of time to complete.</p> 2483<p>The <code>salt</code> should be as unique as possible. It is recommended that a salt is 2484random and at least 16 bytes long. See <a href="https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-132.pdf">NIST SP 800-132</a> for details.</p> 2485<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2486crypto.<span class="hljs-title function_">pbkdf2</span>(<span class="hljs-string">'secret'</span>, <span class="hljs-string">'salt'</span>, <span class="hljs-number">100000</span>, <span class="hljs-number">64</span>, <span class="hljs-string">'sha512'</span>, <span class="hljs-function">(<span class="hljs-params">err, derivedKey</span>) =></span> { 2487 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2488 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(derivedKey.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); <span class="hljs-comment">// '3745e48...08d59ae'</span> 2489});</code></pre> 2490<p>The <code>crypto.DEFAULT_ENCODING</code> property can be used to change the way the 2491<code>derivedKey</code> is passed to the callback. This property, however, has been 2492deprecated and use should be avoided.</p> 2493<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2494crypto.<span class="hljs-property">DEFAULT_ENCODING</span> = <span class="hljs-string">'hex'</span>; 2495crypto.<span class="hljs-title function_">pbkdf2</span>(<span class="hljs-string">'secret'</span>, <span class="hljs-string">'salt'</span>, <span class="hljs-number">100000</span>, <span class="hljs-number">512</span>, <span class="hljs-string">'sha512'</span>, <span class="hljs-function">(<span class="hljs-params">err, derivedKey</span>) =></span> { 2496 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2497 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(derivedKey); <span class="hljs-comment">// '3745e48...aa39b34'</span> 2498});</code></pre> 2499<p>An array of supported digest functions can be retrieved using 2500<a href="#crypto_crypto_gethashes"><code>crypto.getHashes()</code></a>.</p> 2501<p>This API uses libuv's threadpool, which can have surprising and 2502negative performance implications for some applications; see the 2503<a href="cli.html#cli_uv_threadpool_size_size"><code>UV_THREADPOOL_SIZE</code></a> documentation for more information.</p> 2504<h4><code>crypto.pbkdf2Sync(password, salt, iterations, keylen, digest)</code><span><a class="mark" href="#crypto_crypto_pbkdf2sync_password_salt_iterations_keylen_digest" id="crypto_crypto_pbkdf2sync_password_salt_iterations_keylen_digest">#</a></span></h4> 2505<div class="api_metadata"> 2506<details class="changelog"><summary>History</summary> 2507<table> 2508<tbody><tr><th>Version</th><th>Changes</th></tr> 2509<tr><td>v14.0.0</td> 2510<td><p>The <code>iterations</code> parameter is now restricted to positive values. Earlier releases treated other values as one.</p></td></tr> 2511<tr><td>v6.0.0</td> 2512<td><p>Calling this function without passing the <code>digest</code> parameter is deprecated now and will emit a warning.</p></td></tr> 2513<tr><td>v6.0.0</td> 2514<td><p>The default encoding for <code>password</code> if it is a string changed from <code>binary</code> to <code>utf8</code>.</p></td></tr> 2515<tr><td>v0.9.3</td> 2516<td><p><span>Added in: v0.9.3</span></p></td></tr> 2517</tbody></table> 2518</details> 2519</div> 2520<ul> 2521<li><code>password</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2522<li><code>salt</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2523<li><code>iterations</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 2524<li><code>keylen</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 2525<li><code>digest</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2526<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 2527</ul> 2528<p>Provides a synchronous Password-Based Key Derivation Function 2 (PBKDF2) 2529implementation. A selected HMAC digest algorithm specified by <code>digest</code> is 2530applied to derive a key of the requested byte length (<code>keylen</code>) from the 2531<code>password</code>, <code>salt</code> and <code>iterations</code>.</p> 2532<p>If an error occurs an <code>Error</code> will be thrown, otherwise the derived key will be 2533returned as a <a href="buffer.html"><code>Buffer</code></a>.</p> 2534<p>If <code>digest</code> is <code>null</code>, <code>'sha1'</code> will be used. This behavior is deprecated, 2535please specify a <code>digest</code> explicitly.</p> 2536<p>The <code>iterations</code> argument must be a number set as high as possible. The 2537higher the number of iterations, the more secure the derived key will be, 2538but will take a longer amount of time to complete.</p> 2539<p>The <code>salt</code> should be as unique as possible. It is recommended that a salt is 2540random and at least 16 bytes long. See <a href="https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-132.pdf">NIST SP 800-132</a> for details.</p> 2541<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2542<span class="hljs-keyword">const</span> key = crypto.<span class="hljs-title function_">pbkdf2Sync</span>(<span class="hljs-string">'secret'</span>, <span class="hljs-string">'salt'</span>, <span class="hljs-number">100000</span>, <span class="hljs-number">64</span>, <span class="hljs-string">'sha512'</span>); 2543<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(key.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); <span class="hljs-comment">// '3745e48...08d59ae'</span></code></pre> 2544<p>The <code>crypto.DEFAULT_ENCODING</code> property may be used to change the way the 2545<code>derivedKey</code> is returned. This property, however, is deprecated and use 2546should be avoided.</p> 2547<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2548crypto.<span class="hljs-property">DEFAULT_ENCODING</span> = <span class="hljs-string">'hex'</span>; 2549<span class="hljs-keyword">const</span> key = crypto.<span class="hljs-title function_">pbkdf2Sync</span>(<span class="hljs-string">'secret'</span>, <span class="hljs-string">'salt'</span>, <span class="hljs-number">100000</span>, <span class="hljs-number">512</span>, <span class="hljs-string">'sha512'</span>); 2550<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(key); <span class="hljs-comment">// '3745e48...aa39b34'</span></code></pre> 2551<p>An array of supported digest functions can be retrieved using 2552<a href="#crypto_crypto_gethashes"><code>crypto.getHashes()</code></a>.</p> 2553<h4><code>crypto.privateDecrypt(privateKey, buffer)</code><span><a class="mark" href="#crypto_crypto_privatedecrypt_privatekey_buffer" id="crypto_crypto_privatedecrypt_privatekey_buffer">#</a></span></h4> 2554<div class="api_metadata"> 2555<details class="changelog"><summary>History</summary> 2556<table> 2557<tbody><tr><th>Version</th><th>Changes</th></tr> 2558<tr><td>v12.11.0</td> 2559<td><p>The <code>oaepLabel</code> option was added.</p></td></tr> 2560<tr><td>v12.9.0</td> 2561<td><p>The <code>oaepHash</code> option was added.</p></td></tr> 2562<tr><td>v11.6.0</td> 2563<td><p>This function now supports key objects.</p></td></tr> 2564<tr><td>v0.11.14</td> 2565<td><p><span>Added in: v0.11.14</span></p></td></tr> 2566</tbody></table> 2567</details> 2568</div> 2569<ul> 2570<li><code>privateKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> 2571<ul> 2572<li><code>oaepHash</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The hash function to use for OAEP padding and MGF1. 2573<strong>Default:</strong> <code>'sha1'</code></li> 2574<li><code>oaepLabel</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> The label to use for OAEP 2575padding. If not specified, no label is used.</li> 2576<li><code>padding</code> <a href="crypto.html#crypto_crypto_constants_1" class="type"><crypto.constants></a> An optional padding value defined in 2577<code>crypto.constants</code>, which may be: <code>crypto.constants.RSA_NO_PADDING</code>, 2578<code>crypto.constants.RSA_PKCS1_PADDING</code>, or 2579<code>crypto.constants.RSA_PKCS1_OAEP_PADDING</code>.</li> 2580</ul> 2581</li> 2582<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2583<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A new <code>Buffer</code> with the decrypted content.</li> 2584</ul> 2585<p>Decrypts <code>buffer</code> with <code>privateKey</code>. <code>buffer</code> was previously encrypted using 2586the corresponding public key, for example using <a href="#crypto_crypto_publicencrypt_key_buffer"><code>crypto.publicEncrypt()</code></a>.</p> 2587<p>If <code>privateKey</code> is not a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, this function behaves as if 2588<code>privateKey</code> had been passed to <a href="#crypto_crypto_createprivatekey_key"><code>crypto.createPrivateKey()</code></a>. If it is an 2589object, the <code>padding</code> property can be passed. Otherwise, this function uses 2590<code>RSA_PKCS1_OAEP_PADDING</code>.</p> 2591<h4><code>crypto.privateEncrypt(privateKey, buffer)</code><span><a class="mark" href="#crypto_crypto_privateencrypt_privatekey_buffer" id="crypto_crypto_privateencrypt_privatekey_buffer">#</a></span></h4> 2592<div class="api_metadata"> 2593<details class="changelog"><summary>History</summary> 2594<table> 2595<tbody><tr><th>Version</th><th>Changes</th></tr> 2596<tr><td>v11.6.0</td> 2597<td><p>This function now supports key objects.</p></td></tr> 2598<tr><td>v1.1.0</td> 2599<td><p><span>Added in: v1.1.0</span></p></td></tr> 2600</tbody></table> 2601</details> 2602</div> 2603<ul> 2604<li><code>privateKey</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> 2605<ul> 2606<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> A PEM encoded private key.</li> 2607<li><code>passphrase</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> An optional passphrase for the private key.</li> 2608<li><code>padding</code> <a href="crypto.html#crypto_crypto_constants_1" class="type"><crypto.constants></a> An optional padding value defined in 2609<code>crypto.constants</code>, which may be: <code>crypto.constants.RSA_NO_PADDING</code> or 2610<code>crypto.constants.RSA_PKCS1_PADDING</code>.</li> 2611</ul> 2612</li> 2613<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2614<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A new <code>Buffer</code> with the encrypted content.</li> 2615</ul> 2616<p>Encrypts <code>buffer</code> with <code>privateKey</code>. The returned data can be decrypted using 2617the corresponding public key, for example using <a href="#crypto_crypto_publicdecrypt_key_buffer"><code>crypto.publicDecrypt()</code></a>.</p> 2618<p>If <code>privateKey</code> is not a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, this function behaves as if 2619<code>privateKey</code> had been passed to <a href="#crypto_crypto_createprivatekey_key"><code>crypto.createPrivateKey()</code></a>. If it is an 2620object, the <code>padding</code> property can be passed. Otherwise, this function uses 2621<code>RSA_PKCS1_PADDING</code>.</p> 2622<h4><code>crypto.publicDecrypt(key, buffer)</code><span><a class="mark" href="#crypto_crypto_publicdecrypt_key_buffer" id="crypto_crypto_publicdecrypt_key_buffer">#</a></span></h4> 2623<div class="api_metadata"> 2624<details class="changelog"><summary>History</summary> 2625<table> 2626<tbody><tr><th>Version</th><th>Changes</th></tr> 2627<tr><td>v11.6.0</td> 2628<td><p>This function now supports key objects.</p></td></tr> 2629<tr><td>v1.1.0</td> 2630<td><p><span>Added in: v1.1.0</span></p></td></tr> 2631</tbody></table> 2632</details> 2633</div> 2634<ul> 2635<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> 2636<ul> 2637<li><code>passphrase</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> An optional passphrase for the private key.</li> 2638<li><code>padding</code> <a href="crypto.html#crypto_crypto_constants_1" class="type"><crypto.constants></a> An optional padding value defined in 2639<code>crypto.constants</code>, which may be: <code>crypto.constants.RSA_NO_PADDING</code> or 2640<code>crypto.constants.RSA_PKCS1_PADDING</code>.</li> 2641</ul> 2642</li> 2643<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2644<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A new <code>Buffer</code> with the decrypted content.</li> 2645</ul> 2646<p>Decrypts <code>buffer</code> with <code>key</code>.<code>buffer</code> was previously encrypted using 2647the corresponding private key, for example using <a href="#crypto_crypto_privateencrypt_privatekey_buffer"><code>crypto.privateEncrypt()</code></a>.</p> 2648<p>If <code>key</code> is not a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, this function behaves as if 2649<code>key</code> had been passed to <a href="#crypto_crypto_createpublickey_key"><code>crypto.createPublicKey()</code></a>. If it is an 2650object, the <code>padding</code> property can be passed. Otherwise, this function uses 2651<code>RSA_PKCS1_PADDING</code>.</p> 2652<p>Because RSA public keys can be derived from private keys, a private key may 2653be passed instead of a public key.</p> 2654<h4><code>crypto.publicEncrypt(key, buffer)</code><span><a class="mark" href="#crypto_crypto_publicencrypt_key_buffer" id="crypto_crypto_publicencrypt_key_buffer">#</a></span></h4> 2655<div class="api_metadata"> 2656<details class="changelog"><summary>History</summary> 2657<table> 2658<tbody><tr><th>Version</th><th>Changes</th></tr> 2659<tr><td>v12.11.0</td> 2660<td><p>The <code>oaepLabel</code> option was added.</p></td></tr> 2661<tr><td>v12.9.0</td> 2662<td><p>The <code>oaepHash</code> option was added.</p></td></tr> 2663<tr><td>v11.6.0</td> 2664<td><p>This function now supports key objects.</p></td></tr> 2665<tr><td>v0.11.14</td> 2666<td><p><span>Added in: v0.11.14</span></p></td></tr> 2667</tbody></table> 2668</details> 2669</div> 2670<ul> 2671<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> 2672<ul> 2673<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a> A PEM encoded public or private key.</li> 2674<li><code>oaepHash</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The hash function to use for OAEP padding and MGF1. 2675<strong>Default:</strong> <code>'sha1'</code></li> 2676<li><code>oaepLabel</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> The label to use for OAEP 2677padding. If not specified, no label is used.</li> 2678<li><code>passphrase</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> An optional passphrase for the private key.</li> 2679<li><code>padding</code> <a href="crypto.html#crypto_crypto_constants_1" class="type"><crypto.constants></a> An optional padding value defined in 2680<code>crypto.constants</code>, which may be: <code>crypto.constants.RSA_NO_PADDING</code>, 2681<code>crypto.constants.RSA_PKCS1_PADDING</code>, or 2682<code>crypto.constants.RSA_PKCS1_OAEP_PADDING</code>.</li> 2683</ul> 2684</li> 2685<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2686<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A new <code>Buffer</code> with the encrypted content.</li> 2687</ul> 2688<p>Encrypts the content of <code>buffer</code> with <code>key</code> and returns a new 2689<a href="buffer.html"><code>Buffer</code></a> with encrypted content. The returned data can be decrypted using 2690the corresponding private key, for example using <a href="#crypto_crypto_privatedecrypt_privatekey_buffer"><code>crypto.privateDecrypt()</code></a>.</p> 2691<p>If <code>key</code> is not a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, this function behaves as if 2692<code>key</code> had been passed to <a href="#crypto_crypto_createpublickey_key"><code>crypto.createPublicKey()</code></a>. If it is an 2693object, the <code>padding</code> property can be passed. Otherwise, this function uses 2694<code>RSA_PKCS1_OAEP_PADDING</code>.</p> 2695<p>Because RSA public keys can be derived from private keys, a private key may 2696be passed instead of a public key.</p> 2697<h4><code>crypto.randomBytes(size[, callback])</code><span><a class="mark" href="#crypto_crypto_randombytes_size_callback" id="crypto_crypto_randombytes_size_callback">#</a></span></h4> 2698<div class="api_metadata"> 2699<details class="changelog"><summary>History</summary> 2700<table> 2701<tbody><tr><th>Version</th><th>Changes</th></tr> 2702<tr><td>v9.0.0</td> 2703<td><p>Passing <code>null</code> as the <code>callback</code> argument now throws <code>ERR_INVALID_CALLBACK</code>.</p></td></tr> 2704<tr><td>v0.5.8</td> 2705<td><p><span>Added in: v0.5.8</span></p></td></tr> 2706</tbody></table> 2707</details> 2708</div> 2709<ul> 2710<li><code>size</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 2711<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 2712<ul> 2713<li><code>err</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a></li> 2714<li><code>buf</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 2715</ul> 2716</li> 2717<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> if the <code>callback</code> function is not provided.</li> 2718</ul> 2719<p>Generates cryptographically strong pseudo-random data. The <code>size</code> argument 2720is a number indicating the number of bytes to generate.</p> 2721<p>If a <code>callback</code> function is provided, the bytes are generated asynchronously 2722and the <code>callback</code> function is invoked with two arguments: <code>err</code> and <code>buf</code>. 2723If an error occurs, <code>err</code> will be an <code>Error</code> object; otherwise it is <code>null</code>. The 2724<code>buf</code> argument is a <a href="buffer.html"><code>Buffer</code></a> containing the generated bytes.</p> 2725<pre><code class="language-js"><span class="hljs-comment">// Asynchronous</span> 2726<span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2727crypto.<span class="hljs-title function_">randomBytes</span>(<span class="hljs-number">256</span>, <span class="hljs-function">(<span class="hljs-params">err, buf</span>) =></span> { 2728 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2729 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`<span class="hljs-subst">${buf.length}</span> bytes of random data: <span class="hljs-subst">${buf.toString(<span class="hljs-string">'hex'</span>)}</span>`</span>); 2730});</code></pre> 2731<p>If the <code>callback</code> function is not provided, the random bytes are generated 2732synchronously and returned as a <a href="buffer.html"><code>Buffer</code></a>. An error will be thrown if 2733there is a problem generating the bytes.</p> 2734<pre><code class="language-js"><span class="hljs-comment">// Synchronous</span> 2735<span class="hljs-keyword">const</span> buf = crypto.<span class="hljs-title function_">randomBytes</span>(<span class="hljs-number">256</span>); 2736<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>( 2737 <span class="hljs-string">`<span class="hljs-subst">${buf.length}</span> bytes of random data: <span class="hljs-subst">${buf.toString(<span class="hljs-string">'hex'</span>)}</span>`</span>);</code></pre> 2738<p>The <code>crypto.randomBytes()</code> method will not complete until there is 2739sufficient entropy available. 2740This should normally never take longer than a few milliseconds. The only time 2741when generating the random bytes may conceivably block for a longer period of 2742time is right after boot, when the whole system is still low on entropy.</p> 2743<p>This API uses libuv's threadpool, which can have surprising and 2744negative performance implications for some applications; see the 2745<a href="cli.html#cli_uv_threadpool_size_size"><code>UV_THREADPOOL_SIZE</code></a> documentation for more information.</p> 2746<p>The asynchronous version of <code>crypto.randomBytes()</code> is carried out in a single 2747threadpool request. To minimize threadpool task length variation, partition 2748large <code>randomBytes</code> requests when doing so as part of fulfilling a client 2749request.</p> 2750<h4><code>crypto.randomFillSync(buffer[, offset][, size])</code><span><a class="mark" href="#crypto_crypto_randomfillsync_buffer_offset_size" id="crypto_crypto_randomfillsync_buffer_offset_size">#</a></span></h4> 2751<div class="api_metadata"> 2752<details class="changelog"><summary>History</summary> 2753<table> 2754<tbody><tr><th>Version</th><th>Changes</th></tr> 2755<tr><td>v9.0.0</td> 2756<td><p>The <code>buffer</code> argument may be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 2757<tr><td>v7.10.0, v6.13.0</td> 2758<td><p><span>Added in: v7.10.0, v6.13.0</span></p></td></tr> 2759</tbody></table> 2760</details> 2761</div> 2762<ul> 2763<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> Must be supplied.</li> 2764<li><code>offset</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> <strong>Default:</strong> <code>0</code></li> 2765<li><code>size</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> <strong>Default:</strong> <code>buffer.length - offset</code></li> 2766<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> The object passed as <code>buffer</code> argument.</li> 2767</ul> 2768<p>Synchronous version of <a href="#crypto_crypto_randomfill_buffer_offset_size_callback"><code>crypto.randomFill()</code></a>.</p> 2769<pre><code class="language-js"><span class="hljs-keyword">const</span> buf = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">10</span>); 2770<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(crypto.<span class="hljs-title function_">randomFillSync</span>(buf).<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2771 2772crypto.<span class="hljs-title function_">randomFillSync</span>(buf, <span class="hljs-number">5</span>); 2773<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buf.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2774 2775<span class="hljs-comment">// The above is equivalent to the following:</span> 2776crypto.<span class="hljs-title function_">randomFillSync</span>(buf, <span class="hljs-number">5</span>, <span class="hljs-number">5</span>); 2777<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buf.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>));</code></pre> 2778<p>Any <code>TypedArray</code> or <code>DataView</code> instance may be passed as <code>buffer</code>.</p> 2779<pre><code class="language-js"><span class="hljs-keyword">const</span> a = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Uint</span>32<span class="hljs-built_in">Array</span>(<span class="hljs-number">10</span>); 2780<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(crypto.<span class="hljs-title function_">randomFillSync</span>(a).<span class="hljs-property">buffer</span>, 2781 a.<span class="hljs-property">byteOffset</span>, a.<span class="hljs-property">byteLength</span>).<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2782 2783<span class="hljs-keyword">const</span> b = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Float</span>64<span class="hljs-built_in">Array</span>(<span class="hljs-number">10</span>); 2784<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(crypto.<span class="hljs-title function_">randomFillSync</span>(b).<span class="hljs-property">buffer</span>, 2785 b.<span class="hljs-property">byteOffset</span>, b.<span class="hljs-property">byteLength</span>).<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2786 2787<span class="hljs-keyword">const</span> c = <span class="hljs-keyword">new</span> <span class="hljs-title class_">DataView</span>(<span class="hljs-keyword">new</span> <span class="hljs-title class_">ArrayBuffer</span>(<span class="hljs-number">10</span>)); 2788<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(crypto.<span class="hljs-title function_">randomFillSync</span>(c).<span class="hljs-property">buffer</span>, 2789 c.<span class="hljs-property">byteOffset</span>, c.<span class="hljs-property">byteLength</span>).<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>));</code></pre> 2790<h4><code>crypto.randomFill(buffer[, offset][, size], callback)</code><span><a class="mark" href="#crypto_crypto_randomfill_buffer_offset_size_callback" id="crypto_crypto_randomfill_buffer_offset_size_callback">#</a></span></h4> 2791<div class="api_metadata"> 2792<details class="changelog"><summary>History</summary> 2793<table> 2794<tbody><tr><th>Version</th><th>Changes</th></tr> 2795<tr><td>v9.0.0</td> 2796<td><p>The <code>buffer</code> argument may be any <code>TypedArray</code> or <code>DataView</code>.</p></td></tr> 2797<tr><td>v7.10.0, v6.13.0</td> 2798<td><p><span>Added in: v7.10.0, v6.13.0</span></p></td></tr> 2799</tbody></table> 2800</details> 2801</div> 2802<ul> 2803<li><code>buffer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a> Must be supplied.</li> 2804<li><code>offset</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> <strong>Default:</strong> <code>0</code></li> 2805<li><code>size</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> <strong>Default:</strong> <code>buffer.length - offset</code></li> 2806<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> <code>function(err, buf) {}</code>.</li> 2807</ul> 2808<p>This function is similar to <a href="#crypto_crypto_randombytes_size_callback"><code>crypto.randomBytes()</code></a> but requires the first 2809argument to be a <a href="buffer.html"><code>Buffer</code></a> that will be filled. It also 2810requires that a callback is passed in.</p> 2811<p>If the <code>callback</code> function is not provided, an error will be thrown.</p> 2812<pre><code class="language-js"><span class="hljs-keyword">const</span> buf = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">alloc</span>(<span class="hljs-number">10</span>); 2813crypto.<span class="hljs-title function_">randomFill</span>(buf, <span class="hljs-function">(<span class="hljs-params">err, buf</span>) =></span> { 2814 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2815 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buf.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2816}); 2817 2818crypto.<span class="hljs-title function_">randomFill</span>(buf, <span class="hljs-number">5</span>, <span class="hljs-function">(<span class="hljs-params">err, buf</span>) =></span> { 2819 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2820 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buf.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2821}); 2822 2823<span class="hljs-comment">// The above is equivalent to the following:</span> 2824crypto.<span class="hljs-title function_">randomFill</span>(buf, <span class="hljs-number">5</span>, <span class="hljs-number">5</span>, <span class="hljs-function">(<span class="hljs-params">err, buf</span>) =></span> { 2825 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2826 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(buf.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2827});</code></pre> 2828<p>Any <code>TypedArray</code> or <code>DataView</code> instance may be passed as <code>buffer</code>.</p> 2829<pre><code class="language-js"><span class="hljs-keyword">const</span> a = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Uint</span>32<span class="hljs-built_in">Array</span>(<span class="hljs-number">10</span>); 2830crypto.<span class="hljs-title function_">randomFill</span>(a, <span class="hljs-function">(<span class="hljs-params">err, buf</span>) =></span> { 2831 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2832 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(buf.<span class="hljs-property">buffer</span>, buf.<span class="hljs-property">byteOffset</span>, buf.<span class="hljs-property">byteLength</span>) 2833 .<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2834}); 2835 2836<span class="hljs-keyword">const</span> b = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Float</span>64<span class="hljs-built_in">Array</span>(<span class="hljs-number">10</span>); 2837crypto.<span class="hljs-title function_">randomFill</span>(b, <span class="hljs-function">(<span class="hljs-params">err, buf</span>) =></span> { 2838 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2839 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(buf.<span class="hljs-property">buffer</span>, buf.<span class="hljs-property">byteOffset</span>, buf.<span class="hljs-property">byteLength</span>) 2840 .<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2841}); 2842 2843<span class="hljs-keyword">const</span> c = <span class="hljs-keyword">new</span> <span class="hljs-title class_">DataView</span>(<span class="hljs-keyword">new</span> <span class="hljs-title class_">ArrayBuffer</span>(<span class="hljs-number">10</span>)); 2844crypto.<span class="hljs-title function_">randomFill</span>(c, <span class="hljs-function">(<span class="hljs-params">err, buf</span>) =></span> { 2845 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2846 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(buf.<span class="hljs-property">buffer</span>, buf.<span class="hljs-property">byteOffset</span>, buf.<span class="hljs-property">byteLength</span>) 2847 .<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); 2848});</code></pre> 2849<p>This API uses libuv's threadpool, which can have surprising and 2850negative performance implications for some applications; see the 2851<a href="cli.html#cli_uv_threadpool_size_size"><code>UV_THREADPOOL_SIZE</code></a> documentation for more information.</p> 2852<p>The asynchronous version of <code>crypto.randomFill()</code> is carried out in a single 2853threadpool request. To minimize threadpool task length variation, partition 2854large <code>randomFill</code> requests when doing so as part of fulfilling a client 2855request.</p> 2856<h4><code>crypto.randomInt([min, ]max[, callback])</code><span><a class="mark" href="#crypto_crypto_randomint_min_max_callback" id="crypto_crypto_randomint_min_max_callback">#</a></span></h4> 2857<div class="api_metadata"> 2858<span>Added in: v14.10.0</span> 2859</div> 2860<ul> 2861<li><code>min</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Start of random range (inclusive). <strong>Default</strong>: <code>0</code>.</li> 2862<li><code>max</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> End of random range (exclusive).</li> 2863<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> <code>function(err, n) {}</code>.</li> 2864</ul> 2865<p>Return a random integer <code>n</code> such that <code>min <= n < max</code>. This 2866implementation avoids <a href="https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle#Modulo_bias">modulo bias</a>.</p> 2867<p>The range (<code>max - min</code>) must be less than 2<sup>48</sup>. <code>min</code> and <code>max</code> must 2868be <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isSafeInteger">safe integers</a>.</p> 2869<p>If the <code>callback</code> function is not provided, the random integer is 2870generated synchronously.</p> 2871<pre><code class="language-js"><span class="hljs-comment">// Asynchronous</span> 2872crypto.<span class="hljs-title function_">randomInt</span>(<span class="hljs-number">3</span>, <span class="hljs-function">(<span class="hljs-params">err, n</span>) =></span> { 2873 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2874 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`Random number chosen from (0, 1, 2): <span class="hljs-subst">${n}</span>`</span>); 2875});</code></pre> 2876<pre><code class="language-js"><span class="hljs-comment">// Synchronous</span> 2877<span class="hljs-keyword">const</span> n = crypto.<span class="hljs-title function_">randomInt</span>(<span class="hljs-number">3</span>); 2878<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`Random number chosen from (0, 1, 2): <span class="hljs-subst">${n}</span>`</span>);</code></pre> 2879<pre><code class="language-js"><span class="hljs-comment">// With `min` argument</span> 2880<span class="hljs-keyword">const</span> n = crypto.<span class="hljs-title function_">randomInt</span>(<span class="hljs-number">1</span>, <span class="hljs-number">7</span>); 2881<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`The dice rolled: <span class="hljs-subst">${n}</span>`</span>);</code></pre> 2882<h4><code>crypto.randomUUID([options])</code><span><a class="mark" href="#crypto_crypto_randomuuid_options" id="crypto_crypto_randomuuid_options">#</a></span></h4> 2883<div class="api_metadata"> 2884<span>Added in: v14.17.0</span> 2885</div> 2886<ul> 2887<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 2888<ul> 2889<li><code>disableEntropyCache</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> By default, to improve performance, 2890Node.js generates and caches enough random data to generate up to 2891128 random UUIDs. To generate a UUID without using the cache, set 2892<code>disableEntropyCache</code> to <code>true</code>. <strong>Defaults</strong>: <code>false</code>.</li> 2893</ul> 2894</li> 2895<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 2896</ul> 2897<p>Generates a random <a href="https://www.rfc-editor.org/rfc/rfc4122.txt">RFC 4122</a> version 4 UUID. The UUID is generated using a 2898cryptographic pseudorandom number generator.</p> 2899<h4><code>crypto.scrypt(password, salt, keylen[, options], callback)</code><span><a class="mark" href="#crypto_crypto_scrypt_password_salt_keylen_options_callback" id="crypto_crypto_scrypt_password_salt_keylen_options_callback">#</a></span></h4> 2900<div class="api_metadata"> 2901<details class="changelog"><summary>History</summary> 2902<table> 2903<tbody><tr><th>Version</th><th>Changes</th></tr> 2904<tr><td>v12.8.0, v10.17.0</td> 2905<td><p>The <code>maxmem</code> value can now be any safe integer.</p></td></tr> 2906<tr><td>v10.9.0</td> 2907<td><p>The <code>cost</code>, <code>blockSize</code> and <code>parallelization</code> option names have been added.</p></td></tr> 2908<tr><td>v10.5.0</td> 2909<td><p><span>Added in: v10.5.0</span></p></td></tr> 2910</tbody></table> 2911</details> 2912</div> 2913<ul> 2914<li><code>password</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2915<li><code>salt</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2916<li><code>keylen</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 2917<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 2918<ul> 2919<li><code>cost</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> CPU/memory cost parameter. Must be a power of two greater 2920than one. <strong>Default:</strong> <code>16384</code>.</li> 2921<li><code>blockSize</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Block size parameter. <strong>Default:</strong> <code>8</code>.</li> 2922<li><code>parallelization</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Parallelization parameter. <strong>Default:</strong> <code>1</code>.</li> 2923<li><code>N</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Alias for <code>cost</code>. Only one of both may be specified.</li> 2924<li><code>r</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Alias for <code>blockSize</code>. Only one of both may be specified.</li> 2925<li><code>p</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Alias for <code>parallelization</code>. Only one of both may be specified.</li> 2926<li><code>maxmem</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Memory upper bound. It is an error when (approximately) 2927<code>128 * N * r > maxmem</code>. <strong>Default:</strong> <code>32 * 1024 * 1024</code>.</li> 2928</ul> 2929</li> 2930<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 2931<ul> 2932<li><code>err</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a></li> 2933<li><code>derivedKey</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 2934</ul> 2935</li> 2936</ul> 2937<p>Provides an asynchronous <a href="https://en.wikipedia.org/wiki/Scrypt">scrypt</a> implementation. Scrypt is a password-based 2938key derivation function that is designed to be expensive computationally and 2939memory-wise in order to make brute-force attacks unrewarding.</p> 2940<p>The <code>salt</code> should be as unique as possible. It is recommended that a salt is 2941random and at least 16 bytes long. See <a href="https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-132.pdf">NIST SP 800-132</a> for details.</p> 2942<p>The <code>callback</code> function is called with two arguments: <code>err</code> and <code>derivedKey</code>. 2943<code>err</code> is an exception object when key derivation fails, otherwise <code>err</code> is 2944<code>null</code>. <code>derivedKey</code> is passed to the callback as a <a href="buffer.html"><code>Buffer</code></a>.</p> 2945<p>An exception is thrown when any of the input arguments specify invalid values 2946or types.</p> 2947<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 2948<span class="hljs-comment">// Using the factory defaults.</span> 2949crypto.<span class="hljs-title function_">scrypt</span>(<span class="hljs-string">'password'</span>, <span class="hljs-string">'salt'</span>, <span class="hljs-number">64</span>, <span class="hljs-function">(<span class="hljs-params">err, derivedKey</span>) =></span> { 2950 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2951 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(derivedKey.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); <span class="hljs-comment">// '3745e48...08d59ae'</span> 2952}); 2953<span class="hljs-comment">// Using a custom N parameter. Must be a power of two.</span> 2954crypto.<span class="hljs-title function_">scrypt</span>(<span class="hljs-string">'password'</span>, <span class="hljs-string">'salt'</span>, <span class="hljs-number">64</span>, { <span class="hljs-attr">N</span>: <span class="hljs-number">1024</span> }, <span class="hljs-function">(<span class="hljs-params">err, derivedKey</span>) =></span> { 2955 <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">throw</span> err; 2956 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(derivedKey.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); <span class="hljs-comment">// '3745e48...aa39b34'</span> 2957});</code></pre> 2958<h4><code>crypto.scryptSync(password, salt, keylen[, options])</code><span><a class="mark" href="#crypto_crypto_scryptsync_password_salt_keylen_options" id="crypto_crypto_scryptsync_password_salt_keylen_options">#</a></span></h4> 2959<div class="api_metadata"> 2960<details class="changelog"><summary>History</summary> 2961<table> 2962<tbody><tr><th>Version</th><th>Changes</th></tr> 2963<tr><td>v12.8.0, v10.17.0</td> 2964<td><p>The <code>maxmem</code> value can now be any safe integer.</p></td></tr> 2965<tr><td>v10.9.0</td> 2966<td><p>The <code>cost</code>, <code>blockSize</code> and <code>parallelization</code> option names have been added.</p></td></tr> 2967<tr><td>v10.5.0</td> 2968<td><p><span>Added in: v10.5.0</span></p></td></tr> 2969</tbody></table> 2970</details> 2971</div> 2972<ul> 2973<li><code>password</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2974<li><code>salt</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 2975<li><code>keylen</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 2976<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 2977<ul> 2978<li><code>cost</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> CPU/memory cost parameter. Must be a power of two greater 2979than one. <strong>Default:</strong> <code>16384</code>.</li> 2980<li><code>blockSize</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Block size parameter. <strong>Default:</strong> <code>8</code>.</li> 2981<li><code>parallelization</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Parallelization parameter. <strong>Default:</strong> <code>1</code>.</li> 2982<li><code>N</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Alias for <code>cost</code>. Only one of both may be specified.</li> 2983<li><code>r</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Alias for <code>blockSize</code>. Only one of both may be specified.</li> 2984<li><code>p</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Alias for <code>parallelization</code>. Only one of both may be specified.</li> 2985<li><code>maxmem</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Memory upper bound. It is an error when (approximately) 2986<code>128 * N * r > maxmem</code>. <strong>Default:</strong> <code>32 * 1024 * 1024</code>.</li> 2987</ul> 2988</li> 2989<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 2990</ul> 2991<p>Provides a synchronous <a href="https://en.wikipedia.org/wiki/Scrypt">scrypt</a> implementation. Scrypt is a password-based 2992key derivation function that is designed to be expensive computationally and 2993memory-wise in order to make brute-force attacks unrewarding.</p> 2994<p>The <code>salt</code> should be as unique as possible. It is recommended that a salt is 2995random and at least 16 bytes long. See <a href="https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-132.pdf">NIST SP 800-132</a> for details.</p> 2996<p>An exception is thrown when key derivation fails, otherwise the derived key is 2997returned as a <a href="buffer.html"><code>Buffer</code></a>.</p> 2998<p>An exception is thrown when any of the input arguments specify invalid values 2999or types.</p> 3000<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 3001<span class="hljs-comment">// Using the factory defaults.</span> 3002<span class="hljs-keyword">const</span> key1 = crypto.<span class="hljs-title function_">scryptSync</span>(<span class="hljs-string">'password'</span>, <span class="hljs-string">'salt'</span>, <span class="hljs-number">64</span>); 3003<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(key1.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); <span class="hljs-comment">// '3745e48...08d59ae'</span> 3004<span class="hljs-comment">// Using a custom N parameter. Must be a power of two.</span> 3005<span class="hljs-keyword">const</span> key2 = crypto.<span class="hljs-title function_">scryptSync</span>(<span class="hljs-string">'password'</span>, <span class="hljs-string">'salt'</span>, <span class="hljs-number">64</span>, { <span class="hljs-attr">N</span>: <span class="hljs-number">1024</span> }); 3006<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(key2.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)); <span class="hljs-comment">// '3745e48...aa39b34'</span></code></pre> 3007<h4><code>crypto.setEngine(engine[, flags])</code><span><a class="mark" href="#crypto_crypto_setengine_engine_flags" id="crypto_crypto_setengine_engine_flags">#</a></span></h4> 3008<div class="api_metadata"> 3009<span>Added in: v0.11.11</span> 3010</div> 3011<ul> 3012<li><code>engine</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 3013<li><code>flags</code> <a href="crypto.html#crypto_crypto_constants_1" class="type"><crypto.constants></a> <strong>Default:</strong> <code>crypto.constants.ENGINE_METHOD_ALL</code></li> 3014</ul> 3015<p>Load and set the <code>engine</code> for some or all OpenSSL functions (selected by flags).</p> 3016<p><code>engine</code> could be either an id or a path to the engine's shared library.</p> 3017<p>The optional <code>flags</code> argument uses <code>ENGINE_METHOD_ALL</code> by default. The <code>flags</code> 3018is a bit field taking one of or a mix of the following flags (defined in 3019<code>crypto.constants</code>):</p> 3020<ul> 3021<li><code>crypto.constants.ENGINE_METHOD_RSA</code></li> 3022<li><code>crypto.constants.ENGINE_METHOD_DSA</code></li> 3023<li><code>crypto.constants.ENGINE_METHOD_DH</code></li> 3024<li><code>crypto.constants.ENGINE_METHOD_RAND</code></li> 3025<li><code>crypto.constants.ENGINE_METHOD_EC</code></li> 3026<li><code>crypto.constants.ENGINE_METHOD_CIPHERS</code></li> 3027<li><code>crypto.constants.ENGINE_METHOD_DIGESTS</code></li> 3028<li><code>crypto.constants.ENGINE_METHOD_PKEY_METHS</code></li> 3029<li><code>crypto.constants.ENGINE_METHOD_PKEY_ASN1_METHS</code></li> 3030<li><code>crypto.constants.ENGINE_METHOD_ALL</code></li> 3031<li><code>crypto.constants.ENGINE_METHOD_NONE</code></li> 3032</ul> 3033<p>The flags below are deprecated in OpenSSL-1.1.0.</p> 3034<ul> 3035<li><code>crypto.constants.ENGINE_METHOD_ECDH</code></li> 3036<li><code>crypto.constants.ENGINE_METHOD_ECDSA</code></li> 3037<li><code>crypto.constants.ENGINE_METHOD_STORE</code></li> 3038</ul> 3039<h4><code>crypto.setFips(bool)</code><span><a class="mark" href="#crypto_crypto_setfips_bool" id="crypto_crypto_setfips_bool">#</a></span></h4> 3040<div class="api_metadata"> 3041<span>Added in: v10.0.0</span> 3042</div> 3043<ul> 3044<li><code>bool</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> to enable FIPS mode.</li> 3045</ul> 3046<p>Enables the FIPS compliant crypto provider in a FIPS-enabled Node.js build. 3047Throws an error if FIPS mode is not available.</p> 3048<h4><code>crypto.sign(algorithm, data, key)</code><span><a class="mark" href="#crypto_crypto_sign_algorithm_data_key" id="crypto_crypto_sign_algorithm_data_key">#</a></span></h4> 3049<div class="api_metadata"> 3050<details class="changelog"><summary>History</summary> 3051<table> 3052<tbody><tr><th>Version</th><th>Changes</th></tr> 3053<tr><td>v13.2.0, v12.16.0</td> 3054<td><p>This function now supports IEEE-P1363 DSA and ECDSA signatures.</p></td></tr> 3055<tr><td>v12.0.0</td> 3056<td><p><span>Added in: v12.0.0</span></p></td></tr> 3057</tbody></table> 3058</details> 3059</div> 3060<ul> 3061<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Null_type" class="type"><null></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type" class="type"><undefined></a></li> 3062<li><code>data</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 3063<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 3064<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 3065</ul> 3066<p>Calculates and returns the signature for <code>data</code> using the given private key and 3067algorithm. If <code>algorithm</code> is <code>null</code> or <code>undefined</code>, then the algorithm is 3068dependent upon the key type (especially Ed25519 and Ed448).</p> 3069<p>If <code>key</code> is not a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, this function behaves as if <code>key</code> had been 3070passed to <a href="#crypto_crypto_createprivatekey_key"><code>crypto.createPrivateKey()</code></a>. If it is an object, the following 3071additional properties can be passed:</p> 3072<ul> 3073<li> 3074<p><code>dsaEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> For DSA and ECDSA, this option specifies the 3075format of the generated signature. It can be one of the following:</p> 3076<ul> 3077<li><code>'der'</code> (default): DER-encoded ASN.1 signature structure encoding <code>(r, s)</code>.</li> 3078<li><code>'ieee-p1363'</code>: Signature format <code>r || s</code> as proposed in IEEE-P1363.</li> 3079</ul> 3080</li> 3081<li> 3082<p><code>padding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Optional padding value for RSA, one of the following:</p> 3083<ul> 3084<li><code>crypto.constants.RSA_PKCS1_PADDING</code> (default)</li> 3085<li><code>crypto.constants.RSA_PKCS1_PSS_PADDING</code></li> 3086</ul> 3087<p><code>RSA_PKCS1_PSS_PADDING</code> will use MGF1 with the same hash function 3088used to sign the message as specified in section 3.1 of <a href="https://www.rfc-editor.org/rfc/rfc4055.txt">RFC 4055</a>.</p> 3089</li> 3090<li> 3091<p><code>saltLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Salt length for when padding is 3092<code>RSA_PKCS1_PSS_PADDING</code>. The special value 3093<code>crypto.constants.RSA_PSS_SALTLEN_DIGEST</code> sets the salt length to the digest 3094size, <code>crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN</code> (default) sets it to the 3095maximum permissible value.</p> 3096</li> 3097</ul> 3098<h4><code>crypto.timingSafeEqual(a, b)</code><span><a class="mark" href="#crypto_crypto_timingsafeequal_a_b" id="crypto_crypto_timingsafeequal_a_b">#</a></span></h4> 3099<div class="api_metadata"> 3100<span>Added in: v6.6.0</span> 3101</div> 3102<ul> 3103<li><code>a</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 3104<li><code>b</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 3105<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 3106</ul> 3107<p>This function is based on a constant-time algorithm. 3108Returns true if <code>a</code> is equal to <code>b</code>, without leaking timing information that 3109would allow an attacker to guess one of the values. This is suitable for 3110comparing HMAC digests or secret values like authentication cookies or 3111<a href="https://www.w3.org/TR/capability-urls/">capability urls</a>.</p> 3112<p><code>a</code> and <code>b</code> must both be <code>Buffer</code>s, <code>TypedArray</code>s, or <code>DataView</code>s, and they 3113must have the same byte length.</p> 3114<p>If at least one of <code>a</code> and <code>b</code> is a <code>TypedArray</code> with more than one byte per 3115entry, such as <code>Uint16Array</code>, the result will be computed using the platform 3116byte order.</p> 3117<p>Use of <code>crypto.timingSafeEqual</code> does not guarantee that the <em>surrounding</em> code 3118is timing-safe. Care should be taken to ensure that the surrounding code does 3119not introduce timing vulnerabilities.</p> 3120<h4><code>crypto.verify(algorithm, data, key, signature)</code><span><a class="mark" href="#crypto_crypto_verify_algorithm_data_key_signature" id="crypto_crypto_verify_algorithm_data_key_signature">#</a></span></h4> 3121<div class="api_metadata"> 3122<details class="changelog"><summary>History</summary> 3123<table> 3124<tbody><tr><th>Version</th><th>Changes</th></tr> 3125<tr><td>v13.2.0, v12.16.0</td> 3126<td><p>This function now supports IEEE-P1363 DSA and ECDSA signatures.</p></td></tr> 3127<tr><td>v12.0.0</td> 3128<td><p><span>Added in: v12.0.0</span></p></td></tr> 3129</tbody></table> 3130</details> 3131</div> 3132<ul> 3133<li><code>algorithm</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Null_type" class="type"><null></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type" class="type"><undefined></a></li> 3134<li><code>data</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 3135<li><code>key</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="crypto.html#crypto_class_keyobject" class="type"><KeyObject></a></li> 3136<li><code>signature</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray" class="type"><TypedArray></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView" class="type"><DataView></a></li> 3137<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 3138</ul> 3139<p>Verifies the given signature for <code>data</code> using the given key and algorithm. If 3140<code>algorithm</code> is <code>null</code> or <code>undefined</code>, then the algorithm is dependent upon the 3141key type (especially Ed25519 and Ed448).</p> 3142<p>If <code>key</code> is not a <a href="#crypto_class_keyobject"><code>KeyObject</code></a>, this function behaves as if <code>key</code> had been 3143passed to <a href="#crypto_crypto_createpublickey_key"><code>crypto.createPublicKey()</code></a>. If it is an object, the following 3144additional properties can be passed:</p> 3145<ul> 3146<li> 3147<p><code>dsaEncoding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> For DSA and ECDSA, this option specifies the 3148format of the signature. It can be one of the following:</p> 3149<ul> 3150<li><code>'der'</code> (default): DER-encoded ASN.1 signature structure encoding <code>(r, s)</code>.</li> 3151<li><code>'ieee-p1363'</code>: Signature format <code>r || s</code> as proposed in IEEE-P1363.</li> 3152</ul> 3153</li> 3154<li> 3155<p><code>padding</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Optional padding value for RSA, one of the following:</p> 3156<ul> 3157<li><code>crypto.constants.RSA_PKCS1_PADDING</code> (default)</li> 3158<li><code>crypto.constants.RSA_PKCS1_PSS_PADDING</code></li> 3159</ul> 3160<p><code>RSA_PKCS1_PSS_PADDING</code> will use MGF1 with the same hash function 3161used to sign the message as specified in section 3.1 of <a href="https://www.rfc-editor.org/rfc/rfc4055.txt">RFC 4055</a>.</p> 3162</li> 3163<li> 3164<p><code>saltLength</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer></a> Salt length for when padding is 3165<code>RSA_PKCS1_PSS_PADDING</code>. The special value 3166<code>crypto.constants.RSA_PSS_SALTLEN_DIGEST</code> sets the salt length to the digest 3167size, <code>crypto.constants.RSA_PSS_SALTLEN_MAX_SIGN</code> (default) sets it to the 3168maximum permissible value.</p> 3169</li> 3170</ul> 3171<p>The <code>signature</code> argument is the previously calculated signature for the <code>data</code>.</p> 3172<p>Because public keys can be derived from private keys, a private key or a public 3173key may be passed for <code>key</code>.</p> 3174</section><section><h3>Notes<span><a class="mark" href="#crypto_notes" id="crypto_notes">#</a></span></h3> 3175<h4>Legacy streams API (prior to Node.js 0.10)<span><a class="mark" href="#crypto_legacy_streams_api_prior_to_node_js_0_10" id="crypto_legacy_streams_api_prior_to_node_js_0_10">#</a></span></h4> 3176<p>The Crypto module was added to Node.js before there was the concept of a 3177unified Stream API, and before there were <a href="buffer.html"><code>Buffer</code></a> objects for handling 3178binary data. As such, the many of the <code>crypto</code> defined classes have methods not 3179typically found on other Node.js classes that implement the <a href="stream.html">streams</a> 3180API (e.g. <code>update()</code>, <code>final()</code>, or <code>digest()</code>). Also, many methods accepted 3181and returned <code>'latin1'</code> encoded strings by default rather than <code>Buffer</code>s. This 3182default was changed after Node.js v0.8 to use <a href="buffer.html"><code>Buffer</code></a> objects by default 3183instead.</p> 3184<h4>Recent ECDH changes<span><a class="mark" href="#crypto_recent_ecdh_changes" id="crypto_recent_ecdh_changes">#</a></span></h4> 3185<p>Usage of <code>ECDH</code> with non-dynamically generated key pairs has been simplified. 3186Now, <a href="#crypto_ecdh_setprivatekey_privatekey_encoding"><code>ecdh.setPrivateKey()</code></a> can be called with a preselected private key 3187and the associated public point (key) will be computed and stored in the object. 3188This allows code to only store and provide the private part of the EC key pair. 3189<a href="#crypto_ecdh_setprivatekey_privatekey_encoding"><code>ecdh.setPrivateKey()</code></a> now also validates that the private key is valid for 3190the selected curve.</p> 3191<p>The <a href="#crypto_ecdh_setpublickey_publickey_encoding"><code>ecdh.setPublicKey()</code></a> method is now deprecated as its inclusion in the 3192API is not useful. Either a previously stored private key should be set, which 3193automatically generates the associated public key, or <a href="#crypto_ecdh_generatekeys_encoding_format"><code>ecdh.generateKeys()</code></a> 3194should be called. The main drawback of using <a href="#crypto_ecdh_setpublickey_publickey_encoding"><code>ecdh.setPublicKey()</code></a> is that 3195it can be used to put the ECDH key pair into an inconsistent state.</p> 3196<h4>Support for weak or compromised algorithms<span><a class="mark" href="#crypto_support_for_weak_or_compromised_algorithms" id="crypto_support_for_weak_or_compromised_algorithms">#</a></span></h4> 3197<p>The <code>crypto</code> module still supports some algorithms which are already 3198compromised and are not currently recommended for use. The API also allows 3199the use of ciphers and hashes with a small key size that are too weak for safe 3200use.</p> 3201<p>Users should take full responsibility for selecting the crypto 3202algorithm and key size according to their security requirements.</p> 3203<p>Based on the recommendations of <a href="https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-131Ar1.pdf">NIST SP 800-131A</a>:</p> 3204<ul> 3205<li>MD5 and SHA-1 are no longer acceptable where collision resistance is 3206required such as digital signatures.</li> 3207<li>The key used with RSA, DSA, and DH algorithms is recommended to have 3208at least 2048 bits and that of the curve of ECDSA and ECDH at least 3209224 bits, to be safe to use for several years.</li> 3210<li>The DH groups of <code>modp1</code>, <code>modp2</code> and <code>modp5</code> have a key size 3211smaller than 2048 bits and are not recommended.</li> 3212</ul> 3213<p>See the reference for other recommendations and details.</p> 3214<h4>CCM mode<span><a class="mark" href="#crypto_ccm_mode" id="crypto_ccm_mode">#</a></span></h4> 3215<p>CCM is one of the supported <a href="https://en.wikipedia.org/wiki/Authenticated_encryption">AEAD algorithms</a>. Applications which use this 3216mode must adhere to certain restrictions when using the cipher API:</p> 3217<ul> 3218<li>The authentication tag length must be specified during cipher creation by 3219setting the <code>authTagLength</code> option and must be one of 4, 6, 8, 10, 12, 14 or 322016 bytes.</li> 3221<li>The length of the initialization vector (nonce) <code>N</code> must be between 7 and 13 3222bytes (<code>7 ≤ N ≤ 13</code>).</li> 3223<li>The length of the plaintext is limited to <code>2 ** (8 * (15 - N))</code> bytes.</li> 3224<li>When decrypting, the authentication tag must be set via <code>setAuthTag()</code> before 3225calling <code>update()</code>. 3226Otherwise, decryption will fail and <code>final()</code> will throw an error in 3227compliance with section 2.6 of <a href="https://www.rfc-editor.org/rfc/rfc3610.txt">RFC 3610</a>.</li> 3228<li>Using stream methods such as <code>write(data)</code>, <code>end(data)</code> or <code>pipe()</code> in CCM 3229mode might fail as CCM cannot handle more than one chunk of data per instance.</li> 3230<li>When passing additional authenticated data (AAD), the length of the actual 3231message in bytes must be passed to <code>setAAD()</code> via the <code>plaintextLength</code> 3232option. 3233Many crypto libraries include the authentication tag in the ciphertext, 3234which means that they produce ciphertexts of the length 3235<code>plaintextLength + authTagLength</code>. Node.js does not include the authentication 3236tag, so the ciphertext length is always <code>plaintextLength</code>. 3237This is not necessary if no AAD is used.</li> 3238<li>As CCM processes the whole message at once, <code>update()</code> can only be called 3239once.</li> 3240<li>Even though calling <code>update()</code> is sufficient to encrypt/decrypt the message, 3241applications <em>must</em> call <code>final()</code> to compute or verify the 3242authentication tag.</li> 3243</ul> 3244<pre><code class="language-js"><span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'crypto'</span>); 3245 3246<span class="hljs-keyword">const</span> key = <span class="hljs-string">'keykeykeykeykeykeykeykey'</span>; 3247<span class="hljs-keyword">const</span> nonce = crypto.<span class="hljs-title function_">randomBytes</span>(<span class="hljs-number">12</span>); 3248 3249<span class="hljs-keyword">const</span> aad = <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">from</span>(<span class="hljs-string">'0123456789'</span>, <span class="hljs-string">'hex'</span>); 3250 3251<span class="hljs-keyword">const</span> cipher = crypto.<span class="hljs-title function_">createCipheriv</span>(<span class="hljs-string">'aes-192-ccm'</span>, key, nonce, { 3252 <span class="hljs-attr">authTagLength</span>: <span class="hljs-number">16</span> 3253}); 3254<span class="hljs-keyword">const</span> plaintext = <span class="hljs-string">'Hello world'</span>; 3255cipher.<span class="hljs-title function_">setAAD</span>(aad, { 3256 <span class="hljs-attr">plaintextLength</span>: <span class="hljs-title class_">Buffer</span>.<span class="hljs-title function_">byteLength</span>(plaintext) 3257}); 3258<span class="hljs-keyword">const</span> ciphertext = cipher.<span class="hljs-title function_">update</span>(plaintext, <span class="hljs-string">'utf8'</span>); 3259cipher.<span class="hljs-title function_">final</span>(); 3260<span class="hljs-keyword">const</span> tag = cipher.<span class="hljs-title function_">getAuthTag</span>(); 3261 3262<span class="hljs-comment">// Now transmit { ciphertext, nonce, tag }.</span> 3263 3264<span class="hljs-keyword">const</span> decipher = crypto.<span class="hljs-title function_">createDecipheriv</span>(<span class="hljs-string">'aes-192-ccm'</span>, key, nonce, { 3265 <span class="hljs-attr">authTagLength</span>: <span class="hljs-number">16</span> 3266}); 3267decipher.<span class="hljs-title function_">setAuthTag</span>(tag); 3268decipher.<span class="hljs-title function_">setAAD</span>(aad, { 3269 <span class="hljs-attr">plaintextLength</span>: ciphertext.<span class="hljs-property">length</span> 3270}); 3271<span class="hljs-keyword">const</span> receivedPlaintext = decipher.<span class="hljs-title function_">update</span>(ciphertext, <span class="hljs-literal">null</span>, <span class="hljs-string">'utf8'</span>); 3272 3273<span class="hljs-keyword">try</span> { 3274 decipher.<span class="hljs-title function_">final</span>(); 3275} <span class="hljs-keyword">catch</span> (err) { 3276 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'Authentication failed!'</span>); 3277 <span class="hljs-keyword">return</span>; 3278} 3279 3280<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(receivedPlaintext);</code></pre> 3281</section><section><h3>Crypto constants<span><a class="mark" href="#crypto_crypto_constants_1" id="crypto_crypto_constants_1">#</a></span></h3> 3282<p>The following constants exported by <code>crypto.constants</code> apply to various uses of 3283the <code>crypto</code>, <code>tls</code>, and <code>https</code> modules and are generally specific to OpenSSL.</p> 3284<h4>OpenSSL options<span><a class="mark" href="#crypto_openssl_options" id="crypto_openssl_options">#</a></span></h4> 3285<table> 3286 <tbody><tr> 3287 <th>Constant</th> 3288 <th>Description</th> 3289 </tr> 3290 <tr> 3291 <td><code>SSL_OP_ALL</code></td> 3292 <td>Applies multiple bug workarounds within OpenSSL. See 3293 <a href="https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html">https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html</a> 3294 for detail.</td> 3295 </tr> 3296 <tr> 3297 <td><code>SSL_OP_ALLOW_NO_DHE_KEX</code></td> 3298 <td>Instructs OpenSSL to allow a non-[EC]DHE-based key exchange mode 3299 for TLS v1.3</td> 3300 </tr> 3301 <tr> 3302 <td><code>SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION</code></td> 3303 <td>Allows legacy insecure renegotiation between OpenSSL and unpatched 3304 clients or servers. See 3305 <a href="https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html">https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html</a>.</td> 3306 </tr> 3307 <tr> 3308 <td><code>SSL_OP_CIPHER_SERVER_PREFERENCE</code></td> 3309 <td>Attempts to use the server's preferences instead of the client's when 3310 selecting a cipher. Behavior depends on protocol version. See 3311 <a href="https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html">https://www.openssl.org/docs/man1.0.2/ssl/SSL_CTX_set_options.html</a>.</td> 3312 </tr> 3313 <tr> 3314 <td><code>SSL_OP_CISCO_ANYCONNECT</code></td> 3315 <td>Instructs OpenSSL to use Cisco's "speshul" version of DTLS_BAD_VER.</td> 3316 </tr> 3317 <tr> 3318 <td><code>SSL_OP_COOKIE_EXCHANGE</code></td> 3319 <td>Instructs OpenSSL to turn on cookie exchange.</td> 3320 </tr> 3321 <tr> 3322 <td><code>SSL_OP_CRYPTOPRO_TLSEXT_BUG</code></td> 3323 <td>Instructs OpenSSL to add server-hello extension from an early version 3324 of the cryptopro draft.</td> 3325 </tr> 3326 <tr> 3327 <td><code>SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS</code></td> 3328 <td>Instructs OpenSSL to disable a SSL 3.0/TLS 1.0 vulnerability 3329 workaround added in OpenSSL 0.9.6d.</td> 3330 </tr> 3331 <tr> 3332 <td><code>SSL_OP_EPHEMERAL_RSA</code></td> 3333 <td>Instructs OpenSSL to always use the tmp_rsa key when performing RSA 3334 operations.</td> 3335 </tr> 3336 <tr> 3337 <td><code>SSL_OP_LEGACY_SERVER_CONNECT</code></td> 3338 <td>Allows initial connection to servers that do not support RI.</td> 3339 </tr> 3340 <tr> 3341 <td><code>SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER</code></td> 3342 <td></td> 3343 </tr> 3344 <tr> 3345 <td><code>SSL_OP_MICROSOFT_SESS_ID_BUG</code></td> 3346 <td></td> 3347 </tr> 3348 <tr> 3349 <td><code>SSL_OP_MSIE_SSLV2_RSA_PADDING</code></td> 3350 <td>Instructs OpenSSL to disable the workaround for a man-in-the-middle 3351 protocol-version vulnerability in the SSL 2.0 server implementation.</td> 3352 </tr> 3353 <tr> 3354 <td><code>SSL_OP_NETSCAPE_CA_DN_BUG</code></td> 3355 <td></td> 3356 </tr> 3357 <tr> 3358 <td><code>SSL_OP_NETSCAPE_CHALLENGE_BUG</code></td> 3359 <td></td> 3360 </tr> 3361 <tr> 3362 <td><code>SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG</code></td> 3363 <td></td> 3364 </tr> 3365 <tr> 3366 <td><code>SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG</code></td> 3367 <td></td> 3368 </tr> 3369 <tr> 3370 <td><code>SSL_OP_NO_COMPRESSION</code></td> 3371 <td>Instructs OpenSSL to disable support for SSL/TLS compression.</td> 3372 </tr> 3373 <tr> 3374 <td><code>SSL_OP_NO_ENCRYPT_THEN_MAC</code></td> 3375 <td>Instructs OpenSSL to disable encrypt-then-MAC.</td> 3376 </tr> 3377 <tr> 3378 <td><code>SSL_OP_NO_QUERY_MTU</code></td> 3379 <td></td> 3380 </tr> 3381 <tr> 3382 <td><code>SSL_OP_NO_RENEGOTIATION</code></td> 3383 <td>Instructs OpenSSL to disable renegotiation.</td> 3384 </tr> 3385 <tr> 3386 <td><code>SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION</code></td> 3387 <td>Instructs OpenSSL to always start a new session when performing 3388 renegotiation.</td> 3389 </tr> 3390 <tr> 3391 <td><code>SSL_OP_NO_SSLv2</code></td> 3392 <td>Instructs OpenSSL to turn off SSL v2</td> 3393 </tr> 3394 <tr> 3395 <td><code>SSL_OP_NO_SSLv3</code></td> 3396 <td>Instructs OpenSSL to turn off SSL v3</td> 3397 </tr> 3398 <tr> 3399 <td><code>SSL_OP_NO_TICKET</code></td> 3400 <td>Instructs OpenSSL to disable use of RFC4507bis tickets.</td> 3401 </tr> 3402 <tr> 3403 <td><code>SSL_OP_NO_TLSv1</code></td> 3404 <td>Instructs OpenSSL to turn off TLS v1</td> 3405 </tr> 3406 <tr> 3407 <td><code>SSL_OP_NO_TLSv1_1</code></td> 3408 <td>Instructs OpenSSL to turn off TLS v1.1</td> 3409 </tr> 3410 <tr> 3411 <td><code>SSL_OP_NO_TLSv1_2</code></td> 3412 <td>Instructs OpenSSL to turn off TLS v1.2</td> 3413 </tr> 3414 <tr> 3415 <td><code>SSL_OP_NO_TLSv1_3</code></td> 3416 <td>Instructs OpenSSL to turn off TLS v1.3</td> 3417 </tr> 3418 <tr><td><code>SSL_OP_PKCS1_CHECK_1</code></td> 3419 <td></td> 3420 </tr> 3421 <tr> 3422 <td><code>SSL_OP_PKCS1_CHECK_2</code></td> 3423 <td></td> 3424 </tr> 3425 <tr> 3426 <td><code>SSL_OP_PRIORITIZE_CHACHA</code></td> 3427 <td>Instructs OpenSSL server to prioritize ChaCha20Poly1305 3428 when client does. 3429 This option has no effect if 3430 <code>SSL_OP_CIPHER_SERVER_PREFERENCE</code> 3431 is not enabled.</td> 3432 </tr> 3433 <tr> 3434 <td><code>SSL_OP_SINGLE_DH_USE</code></td> 3435 <td>Instructs OpenSSL to always create a new key when using 3436 temporary/ephemeral DH parameters.</td> 3437 </tr> 3438 <tr> 3439 <td><code>SSL_OP_SINGLE_ECDH_USE</code></td> 3440 <td>Instructs OpenSSL to always create a new key when using 3441 temporary/ephemeral ECDH parameters.</td> 3442 </tr> 3443 <tr><td><code>SSL_OP_SSLEAY_080_CLIENT_DH_BUG</code></td> 3444 <td></td> 3445 </tr> 3446 <tr> 3447 <td><code>SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG</code></td> 3448 <td></td> 3449 </tr> 3450 <tr> 3451 <td><code>SSL_OP_TLS_BLOCK_PADDING_BUG</code></td> 3452 <td></td> 3453 </tr> 3454 <tr> 3455 <td><code>SSL_OP_TLS_D5_BUG</code></td> 3456 <td></td> 3457 </tr> 3458 <tr> 3459 <td><code>SSL_OP_TLS_ROLLBACK_BUG</code></td> 3460 <td>Instructs OpenSSL to disable version rollback attack detection.</td> 3461 </tr> 3462</tbody></table> 3463<h4>OpenSSL engine constants<span><a class="mark" href="#crypto_openssl_engine_constants" id="crypto_openssl_engine_constants">#</a></span></h4> 3464<table> 3465 <tbody><tr> 3466 <th>Constant</th> 3467 <th>Description</th> 3468 </tr> 3469 <tr> 3470 <td><code>ENGINE_METHOD_RSA</code></td> 3471 <td>Limit engine usage to RSA</td> 3472 </tr> 3473 <tr> 3474 <td><code>ENGINE_METHOD_DSA</code></td> 3475 <td>Limit engine usage to DSA</td> 3476 </tr> 3477 <tr> 3478 <td><code>ENGINE_METHOD_DH</code></td> 3479 <td>Limit engine usage to DH</td> 3480 </tr> 3481 <tr> 3482 <td><code>ENGINE_METHOD_RAND</code></td> 3483 <td>Limit engine usage to RAND</td> 3484 </tr> 3485 <tr> 3486 <td><code>ENGINE_METHOD_EC</code></td> 3487 <td>Limit engine usage to EC</td> 3488 </tr> 3489 <tr> 3490 <td><code>ENGINE_METHOD_CIPHERS</code></td> 3491 <td>Limit engine usage to CIPHERS</td> 3492 </tr> 3493 <tr> 3494 <td><code>ENGINE_METHOD_DIGESTS</code></td> 3495 <td>Limit engine usage to DIGESTS</td> 3496 </tr> 3497 <tr> 3498 <td><code>ENGINE_METHOD_PKEY_METHS</code></td> 3499 <td>Limit engine usage to PKEY_METHDS</td> 3500 </tr> 3501 <tr> 3502 <td><code>ENGINE_METHOD_PKEY_ASN1_METHS</code></td> 3503 <td>Limit engine usage to PKEY_ASN1_METHS</td> 3504 </tr> 3505 <tr> 3506 <td><code>ENGINE_METHOD_ALL</code></td> 3507 <td></td> 3508 </tr> 3509 <tr> 3510 <td><code>ENGINE_METHOD_NONE</code></td> 3511 <td></td> 3512 </tr> 3513</tbody></table> 3514<h4>Other OpenSSL constants<span><a class="mark" href="#crypto_other_openssl_constants" id="crypto_other_openssl_constants">#</a></span></h4> 3515<p>See the <a href="https://wiki.openssl.org/index.php/List_of_SSL_OP_Flags#Table_of_Options">list of SSL OP Flags</a> for details.</p> 3516<table> 3517 <tbody><tr> 3518 <th>Constant</th> 3519 <th>Description</th> 3520 </tr> 3521 <tr> 3522 <td><code>DH_CHECK_P_NOT_SAFE_PRIME</code></td> 3523 <td></td> 3524 </tr> 3525 <tr> 3526 <td><code>DH_CHECK_P_NOT_PRIME</code></td> 3527 <td></td> 3528 </tr> 3529 <tr> 3530 <td><code>DH_UNABLE_TO_CHECK_GENERATOR</code></td> 3531 <td></td> 3532 </tr> 3533 <tr> 3534 <td><code>DH_NOT_SUITABLE_GENERATOR</code></td> 3535 <td></td> 3536 </tr> 3537 <tr> 3538 <td><code>ALPN_ENABLED</code></td> 3539 <td></td> 3540 </tr> 3541 <tr> 3542 <td><code>RSA_PKCS1_PADDING</code></td> 3543 <td></td> 3544 </tr> 3545 <tr> 3546 <td><code>RSA_SSLV23_PADDING</code></td> 3547 <td></td> 3548 </tr> 3549 <tr> 3550 <td><code>RSA_NO_PADDING</code></td> 3551 <td></td> 3552 </tr> 3553 <tr> 3554 <td><code>RSA_PKCS1_OAEP_PADDING</code></td> 3555 <td></td> 3556 </tr> 3557 <tr> 3558 <td><code>RSA_X931_PADDING</code></td> 3559 <td></td> 3560 </tr> 3561 <tr> 3562 <td><code>RSA_PKCS1_PSS_PADDING</code></td> 3563 <td></td> 3564 </tr> 3565 <tr> 3566 <td><code>RSA_PSS_SALTLEN_DIGEST</code></td> 3567 <td>Sets the salt length for <code>RSA_PKCS1_PSS_PADDING</code> to the 3568 digest size when signing or verifying.</td> 3569 </tr> 3570 <tr> 3571 <td><code>RSA_PSS_SALTLEN_MAX_SIGN</code></td> 3572 <td>Sets the salt length for <code>RSA_PKCS1_PSS_PADDING</code> to the 3573 maximum permissible value when signing data.</td> 3574 </tr> 3575 <tr> 3576 <td><code>RSA_PSS_SALTLEN_AUTO</code></td> 3577 <td>Causes the salt length for <code>RSA_PKCS1_PSS_PADDING</code> to be 3578 determined automatically when verifying a signature.</td> 3579 </tr> 3580 <tr> 3581 <td><code>POINT_CONVERSION_COMPRESSED</code></td> 3582 <td></td> 3583 </tr> 3584 <tr> 3585 <td><code>POINT_CONVERSION_UNCOMPRESSED</code></td> 3586 <td></td> 3587 </tr> 3588 <tr> 3589 <td><code>POINT_CONVERSION_HYBRID</code></td> 3590 <td></td> 3591 </tr> 3592</tbody></table> 3593<h4>Node.js crypto constants<span><a class="mark" href="#crypto_node_js_crypto_constants" id="crypto_node_js_crypto_constants">#</a></span></h4> 3594<table> 3595 <tbody><tr> 3596 <th>Constant</th> 3597 <th>Description</th> 3598 </tr> 3599 <tr> 3600 <td><code>defaultCoreCipherList</code></td> 3601 <td>Specifies the built-in default cipher list used by Node.js.</td> 3602 </tr> 3603 <tr> 3604 <td><code>defaultCipherList</code></td> 3605 <td>Specifies the active default cipher list used by the current Node.js 3606 process.</td> 3607 </tr> 3608</tbody></table></section> 3609 <!-- API END --> 3610 </div> 3611 </div> 3612 </div> 3613 <script> 3614 'use strict'; 3615 { 3616 const kCustomPreference = 'customDarkTheme'; 3617 const userSettings = sessionStorage.getItem(kCustomPreference); 3618 const themeToggleButton = document.getElementById('theme-toggle-btn'); 3619 if (userSettings === null && window.matchMedia) { 3620 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 3621 if ('onchange' in mq) { 3622 function mqChangeListener(e) { 3623 document.body.classList.toggle('dark-mode', e.matches); 3624 } 3625 mq.addEventListener('change', mqChangeListener); 3626 if (themeToggleButton) { 3627 themeToggleButton.addEventListener('click', function() { 3628 mq.removeEventListener('change', mqChangeListener); 3629 }, { once: true }); 3630 } 3631 } 3632 if (mq.matches) { 3633 document.body.classList.add('dark-mode'); 3634 } 3635 } else 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