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<header> 91 <div class="header-container"> 92 <h1>Node.js v14.21.2 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 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href="#tls_session_identifiers">Session identifiers</a></li> 157<li><a href="#tls_session_tickets">Session tickets</a></li> 158</ul> 159</li> 160</ul> 161</li> 162<li><a href="#tls_modifying_the_default_tls_cipher_suite">Modifying the default TLS cipher suite</a></li> 163<li><span class="stability_0"><a href="#tls_class_tls_cryptostream">Class: <code>tls.CryptoStream</code></a></span> 164<ul> 165<li><a href="#tls_cryptostream_byteswritten"><code>cryptoStream.bytesWritten</code></a></li> 166</ul> 167</li> 168<li><span class="stability_0"><a href="#tls_class_tls_securepair">Class: <code>tls.SecurePair</code></a></span> 169<ul> 170<li><a href="#tls_event_secure">Event: <code>'secure'</code></a></li> 171</ul> 172</li> 173<li><a href="#tls_class_tls_server">Class: <code>tls.Server</code></a> 174<ul> 175<li><a href="#tls_event_connection">Event: <code>'connection'</code></a></li> 176<li><a href="#tls_event_keylog">Event: <code>'keylog'</code></a></li> 177<li><a href="#tls_event_newsession">Event: <code>'newSession'</code></a></li> 178<li><a href="#tls_event_ocsprequest">Event: <code>'OCSPRequest'</code></a></li> 179<li><a href="#tls_event_resumesession">Event: <code>'resumeSession'</code></a></li> 180<li><a href="#tls_event_secureconnection">Event: <code>'secureConnection'</code></a></li> 181<li><a href="#tls_event_tlsclienterror">Event: <code>'tlsClientError'</code></a></li> 182<li><a href="#tls_server_addcontext_hostname_context"><code>server.addContext(hostname, context)</code></a></li> 183<li><a href="#tls_server_address"><code>server.address()</code></a></li> 184<li><a href="#tls_server_close_callback"><code>server.close([callback])</code></a></li> 185<li><span class="stability_0"><a href="#tls_server_connections"><code>server.connections</code></a></span></li> 186<li><a href="#tls_server_getticketkeys"><code>server.getTicketKeys()</code></a></li> 187<li><a href="#tls_server_listen"><code>server.listen()</code></a></li> 188<li><a href="#tls_server_setsecurecontext_options"><code>server.setSecureContext(options)</code></a></li> 189<li><a href="#tls_server_setticketkeys_keys"><code>server.setTicketKeys(keys)</code></a></li> 190</ul> 191</li> 192<li><a href="#tls_class_tls_tlssocket">Class: <code>tls.TLSSocket</code></a> 193<ul> 194<li><a href="#tls_new_tls_tlssocket_socket_options"><code>new tls.TLSSocket(socket[, options])</code></a></li> 195<li><a href="#tls_event_keylog_1">Event: <code>'keylog'</code></a></li> 196<li><a href="#tls_event_ocspresponse">Event: <code>'OCSPResponse'</code></a></li> 197<li><a href="#tls_event_secureconnect">Event: <code>'secureConnect'</code></a></li> 198<li><a href="#tls_event_session">Event: <code>'session'</code></a></li> 199<li><a href="#tls_tlssocket_address"><code>tlsSocket.address()</code></a></li> 200<li><a href="#tls_tlssocket_authorizationerror"><code>tlsSocket.authorizationError</code></a></li> 201<li><a href="#tls_tlssocket_authorized"><code>tlsSocket.authorized</code></a></li> 202<li><a href="#tls_tlssocket_disablerenegotiation"><code>tlsSocket.disableRenegotiation()</code></a></li> 203<li><a href="#tls_tlssocket_enabletrace"><code>tlsSocket.enableTrace()</code></a></li> 204<li><a href="#tls_tlssocket_encrypted"><code>tlsSocket.encrypted</code></a></li> 205<li><a href="#tls_tlssocket_getcertificate"><code>tlsSocket.getCertificate()</code></a></li> 206<li><a href="#tls_tlssocket_getcipher"><code>tlsSocket.getCipher()</code></a></li> 207<li><a href="#tls_tlssocket_getephemeralkeyinfo"><code>tlsSocket.getEphemeralKeyInfo()</code></a></li> 208<li><a href="#tls_tlssocket_getfinished"><code>tlsSocket.getFinished()</code></a></li> 209<li><a href="#tls_tlssocket_getpeercertificate_detailed"><code>tlsSocket.getPeerCertificate([detailed])</code></a> 210<ul> 211<li><a href="#tls_certificate_object">Certificate object</a></li> 212</ul> 213</li> 214<li><a href="#tls_tlssocket_getpeerfinished"><code>tlsSocket.getPeerFinished()</code></a></li> 215<li><a href="#tls_tlssocket_getprotocol"><code>tlsSocket.getProtocol()</code></a></li> 216<li><a href="#tls_tlssocket_getsession"><code>tlsSocket.getSession()</code></a></li> 217<li><a href="#tls_tlssocket_getsharedsigalgs"><code>tlsSocket.getSharedSigalgs()</code></a></li> 218<li><a href="#tls_tlssocket_exportkeyingmaterial_length_label_context"><code>tlsSocket.exportKeyingMaterial(length, label[, context])</code></a></li> 219<li><a href="#tls_tlssocket_gettlsticket"><code>tlsSocket.getTLSTicket()</code></a></li> 220<li><a href="#tls_tlssocket_issessionreused"><code>tlsSocket.isSessionReused()</code></a></li> 221<li><a href="#tls_tlssocket_localaddress"><code>tlsSocket.localAddress</code></a></li> 222<li><a href="#tls_tlssocket_localport"><code>tlsSocket.localPort</code></a></li> 223<li><a href="#tls_tlssocket_remoteaddress"><code>tlsSocket.remoteAddress</code></a></li> 224<li><a href="#tls_tlssocket_remotefamily"><code>tlsSocket.remoteFamily</code></a></li> 225<li><a href="#tls_tlssocket_remoteport"><code>tlsSocket.remotePort</code></a></li> 226<li><a href="#tls_tlssocket_renegotiate_options_callback"><code>tlsSocket.renegotiate(options, callback)</code></a></li> 227<li><a href="#tls_tlssocket_setmaxsendfragment_size"><code>tlsSocket.setMaxSendFragment(size)</code></a></li> 228</ul> 229</li> 230<li><a href="#tls_tls_checkserveridentity_hostname_cert"><code>tls.checkServerIdentity(hostname, cert)</code></a></li> 231<li><a href="#tls_tls_connect_options_callback"><code>tls.connect(options[, callback])</code></a></li> 232<li><a href="#tls_tls_connect_path_options_callback"><code>tls.connect(path[, options][, callback])</code></a></li> 233<li><a href="#tls_tls_connect_port_host_options_callback"><code>tls.connect(port[, host][, options][, callback])</code></a></li> 234<li><a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext([options])</code></a></li> 235<li><span class="stability_0"><a href="#tls_tls_createsecurepair_context_isserver_requestcert_rejectunauthorized_options"><code>tls.createSecurePair([context][, isServer][, requestCert][, rejectUnauthorized][, options])</code></a></span></li> 236<li><a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer([options][, secureConnectionListener])</code></a></li> 237<li><a href="#tls_tls_getciphers"><code>tls.getCiphers()</code></a></li> 238<li><a href="#tls_tls_rootcertificates"><code>tls.rootCertificates</code></a></li> 239<li><a href="#tls_tls_default_ecdh_curve"><code>tls.DEFAULT_ECDH_CURVE</code></a></li> 240<li><a href="#tls_tls_default_max_version"><code>tls.DEFAULT_MAX_VERSION</code></a></li> 241<li><a href="#tls_tls_default_min_version"><code>tls.DEFAULT_MIN_VERSION</code></a></li> 242</ul> 243</li> 244</ul></details> 245 246 <div id="apicontent"> 247 <h2>TLS (SSL)<span><a class="mark" href="#tls_tls_ssl" id="tls_tls_ssl">#</a></span></h2> 248 249<p></p><div class="api_stability api_stability_2"><a href="documentation.html#documentation_stability_index">Stability: 2</a> - Stable</div><p></p> 250<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v14.21.2/lib/tls.js">lib/tls.js</a></p> 251<p>The <code>tls</code> module provides an implementation of the Transport Layer Security 252(TLS) and Secure Socket Layer (SSL) protocols that is built on top of OpenSSL. 253The module can be accessed using:</p> 254<pre><code class="language-js"><span class="hljs-keyword">const</span> tls = <span class="hljs-built_in">require</span>(<span class="hljs-string">'tls'</span>);</code></pre> 255<section><h3>TLS/SSL concepts<span><a class="mark" href="#tls_tls_ssl_concepts" id="tls_tls_ssl_concepts">#</a></span></h3> 256<p>The TLS/SSL is a public/private key infrastructure (PKI). For most common 257cases, each client and server must have a <em>private key</em>.</p> 258<p>Private keys can be generated in multiple ways. The example below illustrates 259use of the OpenSSL command-line interface to generate a 2048-bit RSA private 260key:</p> 261<pre><code class="language-bash">openssl genrsa -out ryans-key.pem 2048</code></pre> 262<p>With TLS/SSL, all servers (and some clients) must have a <em>certificate</em>. 263Certificates are <em>public keys</em> that correspond to a private key, and that are 264digitally signed either by a Certificate Authority or by the owner of the 265private key (such certificates are referred to as "self-signed"). The first 266step to obtaining a certificate is to create a <em>Certificate Signing Request</em> 267(CSR) file.</p> 268<p>The OpenSSL command-line interface can be used to generate a CSR for a private 269key:</p> 270<pre><code class="language-bash">openssl req -new -sha256 -key ryans-key.pem -out ryans-csr.pem</code></pre> 271<p>Once the CSR file is generated, it can either be sent to a Certificate 272Authority for signing or used to generate a self-signed certificate.</p> 273<p>Creating a self-signed certificate using the OpenSSL command-line interface 274is illustrated in the example below:</p> 275<pre><code class="language-bash">openssl x509 -req -<span class="hljs-keyword">in</span> ryans-csr.pem -signkey ryans-key.pem -out ryans-cert.pem</code></pre> 276<p>Once the certificate is generated, it can be used to generate a <code>.pfx</code> or 277<code>.p12</code> file:</p> 278<pre><code class="language-bash">openssl pkcs12 -<span class="hljs-built_in">export</span> -<span class="hljs-keyword">in</span> ryans-cert.pem -inkey ryans-key.pem \ 279 -certfile ca-cert.pem -out ryans.pfx</code></pre> 280<p>Where:</p> 281<ul> 282<li><code>in</code>: is the signed certificate</li> 283<li><code>inkey</code>: is the associated private key</li> 284<li><code>certfile</code>: is a concatenation of all Certificate Authority (CA) certs into 285a single file, e.g. <code>cat ca1-cert.pem ca2-cert.pem > ca-cert.pem</code></li> 286</ul> 287<h4>Perfect forward secrecy<span><a class="mark" href="#tls_perfect_forward_secrecy" id="tls_perfect_forward_secrecy">#</a></span></h4> 288 289<p>The term <em><a href="https://en.wikipedia.org/wiki/Perfect_forward_secrecy">forward secrecy</a></em> or <em>perfect forward secrecy</em> describes a feature 290of key-agreement (i.e., key-exchange) methods. That is, the server and client 291keys are used to negotiate new temporary keys that are used specifically and 292only for the current communication session. Practically, this means that even 293if the server's private key is compromised, communication can only be decrypted 294by eavesdroppers if the attacker manages to obtain the key-pair specifically 295generated for the session.</p> 296<p>Perfect forward secrecy is achieved by randomly generating a key pair for 297key-agreement on every TLS/SSL handshake (in contrast to using the same key for 298all sessions). Methods implementing this technique are called "ephemeral".</p> 299<p>Currently two methods are commonly used to achieve perfect forward secrecy (note 300the character "E" appended to the traditional abbreviations):</p> 301<ul> 302<li><a href="https://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exchange">DHE</a>: An ephemeral version of the Diffie-Hellman key-agreement protocol.</li> 303<li><a href="https://en.wikipedia.org/wiki/Elliptic_curve_Diffie%E2%80%93Hellman">ECDHE</a>: An ephemeral version of the Elliptic Curve Diffie-Hellman 304key-agreement protocol.</li> 305</ul> 306<p>Ephemeral methods may have some performance drawbacks, because key generation 307is expensive.</p> 308<p>To use perfect forward secrecy using <code>DHE</code> with the <code>tls</code> module, it is required 309to generate Diffie-Hellman parameters and specify them with the <code>dhparam</code> 310option to <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. The following illustrates the use of 311the OpenSSL command-line interface to generate such parameters:</p> 312<pre><code class="language-bash">openssl dhparam -outform PEM -out dhparam.pem 2048</code></pre> 313<p>If using perfect forward secrecy using <code>ECDHE</code>, Diffie-Hellman parameters are 314not required and a default ECDHE curve will be used. The <code>ecdhCurve</code> property 315can be used when creating a TLS Server to specify the list of names of supported 316curves to use, see <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a> for more info.</p> 317<p>Perfect forward secrecy was optional up to TLSv1.2, but it is not optional for 318TLSv1.3, because all TLSv1.3 cipher suites use ECDHE.</p> 319<h4>ALPN and SNI<span><a class="mark" href="#tls_alpn_and_sni" id="tls_alpn_and_sni">#</a></span></h4> 320 321<p>ALPN (Application-Layer Protocol Negotiation Extension) and 322SNI (Server Name Indication) are TLS handshake extensions:</p> 323<ul> 324<li>ALPN: Allows the use of one TLS server for multiple protocols (HTTP, HTTP/2)</li> 325<li>SNI: Allows the use of one TLS server for multiple hostnames with different 326SSL certificates.</li> 327</ul> 328<h4>Pre-shared keys<span><a class="mark" href="#tls_pre_shared_keys" id="tls_pre_shared_keys">#</a></span></h4> 329 330<p>TLS-PSK support is available as an alternative to normal certificate-based 331authentication. It uses a pre-shared key instead of certificates to 332authenticate a TLS connection, providing mutual authentication. 333TLS-PSK and public key infrastructure are not mutually exclusive. Clients and 334servers can accommodate both, choosing either of them during the normal cipher 335negotiation step.</p> 336<p>TLS-PSK is only a good choice where means exist to securely share a 337key with every connecting machine, so it does not replace PKI 338(Public Key Infrastructure) for the majority of TLS uses. 339The TLS-PSK implementation in OpenSSL has seen many security flaws in 340recent years, mostly because it is used only by a minority of applications. 341Please consider all alternative solutions before switching to PSK ciphers. 342Upon generating PSK it is of critical importance to use sufficient entropy as 343discussed in <a href="https://tools.ietf.org/html/rfc4086">RFC 4086</a>. Deriving a shared secret from a password or other 344low-entropy sources is not secure.</p> 345<p>PSK ciphers are disabled by default, and using TLS-PSK thus requires explicitly 346specifying a cipher suite with the <code>ciphers</code> option. The list of available 347ciphers can be retrieved via <code>openssl ciphers -v 'PSK'</code>. All TLS 1.3 348ciphers are eligible for PSK but currently only those that use SHA256 digest are 349supported they can be retrieved via <code>openssl ciphers -v -s -tls1_3 -psk</code>.</p> 350<p>According to the <a href="https://tools.ietf.org/html/rfc4279">RFC 4279</a>, PSK identities up to 128 bytes in length and 351PSKs up to 64 bytes in length must be supported. As of OpenSSL 1.1.0 352maximum identity size is 128 bytes, and maximum PSK length is 256 bytes.</p> 353<p>The current implementation doesn't support asynchronous PSK callbacks due to the 354limitations of the underlying OpenSSL API.</p> 355<h4>Client-initiated renegotiation attack mitigation<span><a class="mark" href="#tls_client_initiated_renegotiation_attack_mitigation" id="tls_client_initiated_renegotiation_attack_mitigation">#</a></span></h4> 356 357<p>The TLS protocol allows clients to renegotiate certain aspects of the TLS 358session. Unfortunately, session renegotiation requires a disproportionate amount 359of server-side resources, making it a potential vector for denial-of-service 360attacks.</p> 361<p>To mitigate the risk, renegotiation is limited to three times every ten minutes. 362An <code>'error'</code> event is emitted on the <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a> instance when this 363threshold is exceeded. The limits are configurable:</p> 364<ul> 365<li><code>tls.CLIENT_RENEG_LIMIT</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Specifies the number of renegotiation 366requests. <strong>Default:</strong> <code>3</code>.</li> 367<li><code>tls.CLIENT_RENEG_WINDOW</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Specifies the time renegotiation window 368in seconds. <strong>Default:</strong> <code>600</code> (10 minutes).</li> 369</ul> 370<p>The default renegotiation limits should not be modified without a full 371understanding of the implications and risks.</p> 372<p>TLSv1.3 does not support renegotiation.</p> 373<h4>Session resumption<span><a class="mark" href="#tls_session_resumption" id="tls_session_resumption">#</a></span></h4> 374<p>Establishing a TLS session can be relatively slow. The process can be sped 375up by saving and later reusing the session state. There are several mechanisms 376to do so, discussed here from oldest to newest (and preferred).</p> 377<h5>Session identifiers<span><a class="mark" href="#tls_session_identifiers" id="tls_session_identifiers">#</a></span></h5> 378<p>Servers generate a unique ID for new connections and 379send it to the client. Clients and servers save the session state. When 380reconnecting, clients send the ID of their saved session state and if the server 381also has the state for that ID, it can agree to use it. Otherwise, the server 382will create a new session. See <a href="https://www.ietf.org/rfc/rfc2246.txt">RFC 2246</a> for more information, page 23 and 38330.</p> 384<p>Resumption using session identifiers is supported by most web browsers when 385making HTTPS requests.</p> 386<p>For Node.js, clients wait for the <a href="#tls_event_session"><code>'session'</code></a> event to get the session data, 387and provide the data to the <code>session</code> option of a subsequent <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> 388to reuse the session. Servers must 389implement handlers for the <a href="#tls_event_newsession"><code>'newSession'</code></a> and <a href="#tls_event_resumesession"><code>'resumeSession'</code></a> events 390to save and restore the session data using the session ID as the lookup key to 391reuse sessions. To reuse sessions across load balancers or cluster workers, 392servers must use a shared session cache (such as Redis) in their session 393handlers.</p> 394<h5>Session tickets<span><a class="mark" href="#tls_session_tickets" id="tls_session_tickets">#</a></span></h5> 395<p>The servers encrypt the entire session state and send it 396to the client as a "ticket". When reconnecting, the state is sent to the server 397in the initial connection. This mechanism avoids the need for server-side 398session cache. If the server doesn't use the ticket, for any reason (failure 399to decrypt it, it's too old, etc.), it will create a new session and send a new 400ticket. See <a href="https://tools.ietf.org/html/rfc5077">RFC 5077</a> for more information.</p> 401<p>Resumption using session tickets is becoming commonly supported by many web 402browsers when making HTTPS requests.</p> 403<p>For Node.js, clients use the same APIs for resumption with session identifiers 404as for resumption with session tickets. For debugging, if 405<a href="#tls_tlssocket_gettlsticket"><code>tls.TLSSocket.getTLSTicket()</code></a> returns a value, the session data contains a 406ticket, otherwise it contains client-side session state.</p> 407<p>With TLSv1.3, be aware that multiple tickets may be sent by the server, 408resulting in multiple <code>'session'</code> events, see <a href="#tls_event_session"><code>'session'</code></a> for more 409information.</p> 410<p>Single process servers need no specific implementation to use session tickets. 411To use session tickets across server restarts or load balancers, servers must 412all have the same ticket keys. There are three 16-byte keys internally, but the 413tls API exposes them as a single 48-byte buffer for convenience.</p> 414<p>Its possible to get the ticket keys by calling <a href="#tls_server_getticketkeys"><code>server.getTicketKeys()</code></a> on 415one server instance and then distribute them, but it is more reasonable to 416securely generate 48 bytes of secure random data and set them with the 417<code>ticketKeys</code> option of <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>. The keys should be regularly 418regenerated and server's keys can be reset with 419<a href="#tls_server_setticketkeys_keys"><code>server.setTicketKeys()</code></a>.</p> 420<p>Session ticket keys are cryptographic keys, and they <em><strong>must be stored 421securely</strong></em>. With TLS 1.2 and below, if they are compromised all sessions that 422used tickets encrypted with them can be decrypted. They should not be stored 423on disk, and they should be regenerated regularly.</p> 424<p>If clients advertise support for tickets, the server will send them. The 425server can disable tickets by supplying 426<code>require('constants').SSL_OP_NO_TICKET</code> in <code>secureOptions</code>.</p> 427<p>Both session identifiers and session tickets timeout, causing the server to 428create new sessions. The timeout can be configured with the <code>sessionTimeout</code> 429option of <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>.</p> 430<p>For all the mechanisms, when resumption fails, servers will create new sessions. 431Since failing to resume the session does not cause TLS/HTTPS connection 432failures, it is easy to not notice unnecessarily poor TLS performance. The 433OpenSSL CLI can be used to verify that servers are resuming sessions. Use the 434<code>-reconnect</code> option to <code>openssl s_client</code>, for example:</p> 435<pre><code class="language-console"><span class="hljs-meta">$ </span><span class="language-bash">openssl s_client -connect localhost:443 -reconnect</span></code></pre> 436<p>Read through the debug output. The first connection should say "New", for 437example:</p> 438<pre><code class="language-text">New, TLSv1.2, Cipher is ECDHE-RSA-AES128-GCM-SHA256</code></pre> 439<p>Subsequent connections should say "Reused", for example:</p> 440<pre><code class="language-text">Reused, TLSv1.2, Cipher is ECDHE-RSA-AES128-GCM-SHA256</code></pre> 441</section><section><h3>Modifying the default TLS cipher suite<span><a class="mark" href="#tls_modifying_the_default_tls_cipher_suite" id="tls_modifying_the_default_tls_cipher_suite">#</a></span></h3> 442<p>Node.js is built with a default suite of enabled and disabled TLS ciphers. This 443default cipher list can be configured when building Node.js to allow 444distributions to provide their own default list.</p> 445<p>The following command can be used to show the default cipher suite:</p> 446<pre><code class="language-console">node -p crypto.constants.defaultCoreCipherList | tr ':' '\n' 447TLS_AES_256_GCM_SHA384 448TLS_CHACHA20_POLY1305_SHA256 449TLS_AES_128_GCM_SHA256 450ECDHE-RSA-AES128-GCM-SHA256 451ECDHE-ECDSA-AES128-GCM-SHA256 452ECDHE-RSA-AES256-GCM-SHA384 453ECDHE-ECDSA-AES256-GCM-SHA384 454DHE-RSA-AES128-GCM-SHA256 455ECDHE-RSA-AES128-SHA256 456DHE-RSA-AES128-SHA256 457ECDHE-RSA-AES256-SHA384 458DHE-RSA-AES256-SHA384 459ECDHE-RSA-AES256-SHA256 460DHE-RSA-AES256-SHA256 461HIGH 462!aNULL 463!eNULL 464!EXPORT 465!DES 466!RC4 467!MD5 468!PSK 469!SRP 470!CAMELLIA</code></pre> 471<p>This default can be replaced entirely using the <a href="cli.html#cli_tls_cipher_list_list"><code>--tls-cipher-list</code></a> 472command-line switch (directly, or via the <a href="cli.html#cli_node_options_options"><code>NODE_OPTIONS</code></a> environment 473variable). For instance, the following makes <code>ECDHE-RSA-AES128-GCM-SHA256:!RC4</code> 474the default TLS cipher suite:</p> 475<pre><code class="language-bash">node --tls-cipher-list=<span class="hljs-string">'ECDHE-RSA-AES128-GCM-SHA256:!RC4'</span> server.js 476 477<span class="hljs-built_in">export</span> NODE_OPTIONS=--tls-cipher-list=<span class="hljs-string">'ECDHE-RSA-AES128-GCM-SHA256:!RC4'</span> 478node server.js</code></pre> 479<p>The default can also be replaced on a per client or server basis using the 480<code>ciphers</code> option from <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>, which is also available 481in <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>, <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a>, and when creating new 482<a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a>s.</p> 483<p>The ciphers list can contain a mixture of TLSv1.3 cipher suite names, the ones 484that start with <code>'TLS_'</code>, and specifications for TLSv1.2 and below cipher 485suites. The TLSv1.2 ciphers support a legacy specification format, consult 486the OpenSSL <a href="https://www.openssl.org/docs/man1.1.1/man1/ciphers.html#CIPHER-LIST-FORMAT">cipher list format</a> documentation for details, but those 487specifications do <em>not</em> apply to TLSv1.3 ciphers. The TLSv1.3 suites can only 488be enabled by including their full name in the cipher list. They cannot, for 489example, be enabled or disabled by using the legacy TLSv1.2 <code>'EECDH'</code> or 490<code>'!EECDH'</code> specification.</p> 491<p>Despite the relative order of TLSv1.3 and TLSv1.2 cipher suites, the TLSv1.3 492protocol is significantly more secure than TLSv1.2, and will always be chosen 493over TLSv1.2 if the handshake indicates it is supported, and if any TLSv1.3 494cipher suites are enabled.</p> 495<p>The default cipher suite included within Node.js has been carefully 496selected to reflect current security best practices and risk mitigation. 497Changing the default cipher suite can have a significant impact on the security 498of an application. The <code>--tls-cipher-list</code> switch and <code>ciphers</code> option should by 499used only if absolutely necessary.</p> 500<p>The default cipher suite prefers GCM ciphers for <a href="https://www.chromium.org/Home/chromium-security/education/tls#TOC-Cipher-Suites">Chrome's 'modern 501cryptography' setting</a> and also prefers ECDHE and DHE ciphers for perfect 502forward secrecy, while offering <em>some</em> backward compatibility.</p> 503<p>128 bit AES is preferred over 192 and 256 bit AES in light of <a href="https://www.schneier.com/blog/archives/2009/07/another_new_aes.html">specific 504attacks affecting larger AES key sizes</a>.</p> 505<p>Old clients that rely on insecure and deprecated RC4 or DES-based ciphers 506(like Internet Explorer 6) cannot complete the handshaking process with 507the default configuration. If these clients <em>must</em> be supported, the 508<a href="https://wiki.mozilla.org/Security/Server_Side_TLS">TLS recommendations</a> may offer a compatible cipher suite. For more details 509on the format, see the OpenSSL <a href="https://www.openssl.org/docs/man1.1.1/man1/ciphers.html#CIPHER-LIST-FORMAT">cipher list format</a> documentation.</p> 510<p>There are only 5 TLSv1.3 cipher suites:</p> 511<ul> 512<li><code>'TLS_AES_256_GCM_SHA384'</code></li> 513<li><code>'TLS_CHACHA20_POLY1305_SHA256'</code></li> 514<li><code>'TLS_AES_128_GCM_SHA256'</code></li> 515<li><code>'TLS_AES_128_CCM_SHA256'</code></li> 516<li><code>'TLS_AES_128_CCM_8_SHA256'</code></li> 517</ul> 518<p>The first 3 are enabled by default. The last 2 <code>CCM</code>-based suites are supported 519by TLSv1.3 because they may be more performant on constrained systems, but they 520are not enabled by default since they offer less security.</p> 521</section><section><h3>Class: <code>tls.CryptoStream</code><span><a class="mark" href="#tls_class_tls_cryptostream" id="tls_class_tls_cryptostream">#</a></span></h3> 522<div class="api_metadata"> 523<span>Added in: v0.3.4</span><span>Deprecated since: v0.11.3</span> 524</div> 525<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated: Use <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a> instead.</div><p></p> 526<p>The <code>tls.CryptoStream</code> class represents a stream of encrypted data. This class 527is deprecated and should no longer be used.</p> 528<h4><code>cryptoStream.bytesWritten</code><span><a class="mark" href="#tls_cryptostream_byteswritten" id="tls_cryptostream_byteswritten">#</a></span></h4> 529<div class="api_metadata"> 530<span>Added in: v0.3.4</span><span>Deprecated since: v0.11.3</span> 531</div> 532<p>The <code>cryptoStream.bytesWritten</code> property returns the total number of bytes 533written to the underlying socket <em>including</em> the bytes required for the 534implementation of the TLS protocol.</p> 535</section><section><h3>Class: <code>tls.SecurePair</code><span><a class="mark" href="#tls_class_tls_securepair" id="tls_class_tls_securepair">#</a></span></h3> 536<div class="api_metadata"> 537<span>Added in: v0.3.2</span><span>Deprecated since: v0.11.3</span> 538</div> 539<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated: Use <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a> instead.</div><p></p> 540<p>Returned by <a href="#tls_tls_createsecurepair_context_isserver_requestcert_rejectunauthorized_options"><code>tls.createSecurePair()</code></a>.</p> 541<h4>Event: <code>'secure'</code><span><a class="mark" href="#tls_event_secure" id="tls_event_secure">#</a></span></h4> 542<div class="api_metadata"> 543<span>Added in: v0.3.2</span><span>Deprecated since: v0.11.3</span> 544</div> 545<p>The <code>'secure'</code> event is emitted by the <code>SecurePair</code> object once a secure 546connection has been established.</p> 547<p>As with checking for the server 548<a href="#tls_event_secureconnection"><code>'secureConnection'</code></a> 549event, <code>pair.cleartext.authorized</code> should be inspected to confirm whether the 550certificate used is properly authorized.</p> 551</section><section><h3>Class: <code>tls.Server</code><span><a class="mark" href="#tls_class_tls_server" id="tls_class_tls_server">#</a></span></h3> 552<div class="api_metadata"> 553<span>Added in: v0.3.2</span> 554</div> 555<ul> 556<li>Extends: <a href="net.html#net_class_net_server" class="type"><net.Server></a></li> 557</ul> 558<p>Accepts encrypted connections using TLS or SSL.</p> 559<h4>Event: <code>'connection'</code><span><a class="mark" href="#tls_event_connection" id="tls_event_connection">#</a></span></h4> 560<div class="api_metadata"> 561<span>Added in: v0.3.2</span> 562</div> 563<ul> 564<li><code>socket</code> <a href="stream.html#stream_class_stream_duplex" class="type"><stream.Duplex></a></li> 565</ul> 566<p>This event is emitted when a new TCP stream is established, before the TLS 567handshake begins. <code>socket</code> is typically an object of type <a href="net.html#net_class_net_socket"><code>net.Socket</code></a>. 568Usually users will not want to access this event.</p> 569<p>This event can also be explicitly emitted by users to inject connections 570into the TLS server. In that case, any <a href="stream.html#stream_class_stream_duplex"><code>Duplex</code></a> stream can be passed.</p> 571<h4>Event: <code>'keylog'</code><span><a class="mark" href="#tls_event_keylog" id="tls_event_keylog">#</a></span></h4> 572<div class="api_metadata"> 573<span>Added in: v12.3.0, v10.20.0</span> 574</div> 575<ul> 576<li><code>line</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> Line of ASCII text, in NSS <code>SSLKEYLOGFILE</code> format.</li> 577<li><code>tlsSocket</code> <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a> The <code>tls.TLSSocket</code> instance on which it was 578generated.</li> 579</ul> 580<p>The <code>keylog</code> event is emitted when key material is generated or received by 581a connection to this server (typically before handshake has completed, but not 582necessarily). This keying material can be stored for debugging, as it allows 583captured TLS traffic to be decrypted. It may be emitted multiple times for 584each socket.</p> 585<p>A typical use case is to append received lines to a common text file, which 586is later used by software (such as Wireshark) to decrypt the traffic:</p> 587<pre><code class="language-js"><span class="hljs-keyword">const</span> logFile = fs.<span class="hljs-title function_">createWriteStream</span>(<span class="hljs-string">'/tmp/ssl-keys.log'</span>, { <span class="hljs-attr">flags</span>: <span class="hljs-string">'a'</span> }); 588<span class="hljs-comment">// ...</span> 589server.<span class="hljs-title function_">on</span>(<span class="hljs-string">'keylog'</span>, <span class="hljs-function">(<span class="hljs-params">line, tlsSocket</span>) =></span> { 590 <span class="hljs-keyword">if</span> (tlsSocket.<span class="hljs-property">remoteAddress</span> !== <span class="hljs-string">'...'</span>) 591 <span class="hljs-keyword">return</span>; <span class="hljs-comment">// Only log keys for a particular IP</span> 592 logFile.<span class="hljs-title function_">write</span>(line); 593});</code></pre> 594<h4>Event: <code>'newSession'</code><span><a class="mark" href="#tls_event_newsession" id="tls_event_newsession">#</a></span></h4> 595<div class="api_metadata"> 596<details class="changelog"><summary>History</summary> 597<table> 598<tbody><tr><th>Version</th><th>Changes</th></tr> 599<tr><td>v0.11.12</td> 600<td><p>The <code>callback</code> argument is now supported.</p></td></tr> 601<tr><td>v0.9.2</td> 602<td><p><span>Added in: v0.9.2</span></p></td></tr> 603</tbody></table> 604</details> 605</div> 606<p>The <code>'newSession'</code> event is emitted upon creation of a new TLS session. This may 607be used to store sessions in external storage. The data should be provided to 608the <a href="#tls_event_resumesession"><code>'resumeSession'</code></a> callback.</p> 609<p>The listener callback is passed three arguments when called:</p> 610<ul> 611<li><code>sessionId</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The TLS session identifier</li> 612<li><code>sessionData</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The TLS session data</li> 613<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A callback function taking no arguments that must be 614invoked in order for data to be sent or received over the secure connection.</li> 615</ul> 616<p>Listening for this event will have an effect only on connections established 617after the addition of the event listener.</p> 618<h4>Event: <code>'OCSPRequest'</code><span><a class="mark" href="#tls_event_ocsprequest" id="tls_event_ocsprequest">#</a></span></h4> 619<div class="api_metadata"> 620<span>Added in: v0.11.13</span> 621</div> 622<p>The <code>'OCSPRequest'</code> event is emitted when the client sends a certificate status 623request. The listener callback is passed three arguments when called:</p> 624<ul> 625<li><code>certificate</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The server certificate</li> 626<li><code>issuer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The issuer's certificate</li> 627<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A callback function that must be invoked to provide 628the results of the OCSP request.</li> 629</ul> 630<p>The server's current certificate can be parsed to obtain the OCSP URL 631and certificate ID; after obtaining an OCSP response, <code>callback(null, resp)</code> is 632then invoked, where <code>resp</code> is a <code>Buffer</code> instance containing the OCSP response. 633Both <code>certificate</code> and <code>issuer</code> are <code>Buffer</code> DER-representations of the 634primary and issuer's certificates. These can be used to obtain the OCSP 635certificate ID and OCSP endpoint URL.</p> 636<p>Alternatively, <code>callback(null, null)</code> may be called, indicating that there was 637no OCSP response.</p> 638<p>Calling <code>callback(err)</code> will result in a <code>socket.destroy(err)</code> call.</p> 639<p>The typical flow of an OCSP Request is as follows:</p> 640<ol> 641<li>Client connects to the server and sends an <code>'OCSPRequest'</code> (via the status 642info extension in ClientHello).</li> 643<li>Server receives the request and emits the <code>'OCSPRequest'</code> event, calling the 644listener if registered.</li> 645<li>Server extracts the OCSP URL from either the <code>certificate</code> or <code>issuer</code> and 646performs an <a href="https://en.wikipedia.org/wiki/OCSP_stapling">OCSP request</a> to the CA.</li> 647<li>Server receives <code>'OCSPResponse'</code> from the CA and sends it back to the client 648via the <code>callback</code> argument</li> 649<li>Client validates the response and either destroys the socket or performs a 650handshake.</li> 651</ol> 652<p>The <code>issuer</code> can be <code>null</code> if the certificate is either self-signed or the 653issuer is not in the root certificates list. (An issuer may be provided 654via the <code>ca</code> option when establishing the TLS connection.)</p> 655<p>Listening for this event will have an effect only on connections established 656after the addition of the event listener.</p> 657<p>An npm module like <a href="https://www.npmjs.com/package/asn1.js">asn1.js</a> may be used to parse the certificates.</p> 658<h4>Event: <code>'resumeSession'</code><span><a class="mark" href="#tls_event_resumesession" id="tls_event_resumesession">#</a></span></h4> 659<div class="api_metadata"> 660<span>Added in: v0.9.2</span> 661</div> 662<p>The <code>'resumeSession'</code> event is emitted when the client requests to resume a 663previous TLS session. The listener callback is passed two arguments when 664called:</p> 665<ul> 666<li><code>sessionId</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The TLS session identifier</li> 667<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A callback function to be called when the prior session 668has been recovered: <code>callback([err[, sessionData]])</code> 669<ul> 670<li><code>err</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a></li> 671<li><code>sessionData</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 672</ul> 673</li> 674</ul> 675<p>The event listener should perform a lookup in external storage for the 676<code>sessionData</code> saved by the <a href="#tls_event_newsession"><code>'newSession'</code></a> event handler using the given 677<code>sessionId</code>. If found, call <code>callback(null, sessionData)</code> to resume the session. 678If not found, the session cannot be resumed. <code>callback()</code> must be called 679without <code>sessionData</code> so that the handshake can continue and a new session can 680be created. It is possible to call <code>callback(err)</code> to terminate the incoming 681connection and destroy the socket.</p> 682<p>Listening for this event will have an effect only on connections established 683after the addition of the event listener.</p> 684<p>The following illustrates resuming a TLS session:</p> 685<pre><code class="language-js"><span class="hljs-keyword">const</span> tlsSessionStore = {}; 686server.<span class="hljs-title function_">on</span>(<span class="hljs-string">'newSession'</span>, <span class="hljs-function">(<span class="hljs-params">id, data, cb</span>) =></span> { 687 tlsSessionStore[id.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)] = data; 688 <span class="hljs-title function_">cb</span>(); 689}); 690server.<span class="hljs-title function_">on</span>(<span class="hljs-string">'resumeSession'</span>, <span class="hljs-function">(<span class="hljs-params">id, cb</span>) =></span> { 691 <span class="hljs-title function_">cb</span>(<span class="hljs-literal">null</span>, tlsSessionStore[id.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)] || <span class="hljs-literal">null</span>); 692});</code></pre> 693<h4>Event: <code>'secureConnection'</code><span><a class="mark" href="#tls_event_secureconnection" id="tls_event_secureconnection">#</a></span></h4> 694<div class="api_metadata"> 695<span>Added in: v0.3.2</span> 696</div> 697<p>The <code>'secureConnection'</code> event is emitted after the handshaking process for a 698new connection has successfully completed. The listener callback is passed a 699single argument when called:</p> 700<ul> 701<li><code>tlsSocket</code> <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a> The established TLS socket.</li> 702</ul> 703<p>The <code>tlsSocket.authorized</code> property is a <code>boolean</code> indicating whether the 704client has been verified by one of the supplied Certificate Authorities for the 705server. If <code>tlsSocket.authorized</code> is <code>false</code>, then <code>socket.authorizationError</code> 706is set to describe how authorization failed. Depending on the settings 707of the TLS server, unauthorized connections may still be accepted.</p> 708<p>The <code>tlsSocket.alpnProtocol</code> property is a string that contains the selected 709ALPN protocol. When ALPN has no selected protocol, <code>tlsSocket.alpnProtocol</code> 710equals <code>false</code>.</p> 711<p>The <code>tlsSocket.servername</code> property is a string containing the server name 712requested via SNI.</p> 713<h4>Event: <code>'tlsClientError'</code><span><a class="mark" href="#tls_event_tlsclienterror" id="tls_event_tlsclienterror">#</a></span></h4> 714<div class="api_metadata"> 715<span>Added in: v6.0.0</span> 716</div> 717<p>The <code>'tlsClientError'</code> event is emitted when an error occurs before a secure 718connection is established. The listener callback is passed two arguments when 719called:</p> 720<ul> 721<li><code>exception</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a> The <code>Error</code> object describing the error</li> 722<li><code>tlsSocket</code> <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a> The <code>tls.TLSSocket</code> instance from which the 723error originated.</li> 724</ul> 725<h4><code>server.addContext(hostname, context)</code><span><a class="mark" href="#tls_server_addcontext_hostname_context" id="tls_server_addcontext_hostname_context">#</a></span></h4> 726<div class="api_metadata"> 727<span>Added in: v0.5.3</span> 728</div> 729<ul> 730<li><code>hostname</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> A SNI host name or wildcard (e.g. <code>'*'</code>)</li> 731<li><code>context</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> An object containing any of the possible properties 732from the <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> <code>options</code> arguments (e.g. <code>key</code>, 733<code>cert</code>, <code>ca</code>, etc).</li> 734</ul> 735<p>The <code>server.addContext()</code> method adds a secure context that will be used if 736the client request's SNI name matches the supplied <code>hostname</code> (or wildcard).</p> 737<h4><code>server.address()</code><span><a class="mark" href="#tls_server_address" id="tls_server_address">#</a></span></h4> 738<div class="api_metadata"> 739<span>Added in: v0.6.0</span> 740</div> 741<ul> 742<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 743</ul> 744<p>Returns the bound address, the address family name, and port of the 745server as reported by the operating system. See <a href="net.html#net_server_address"><code>net.Server.address()</code></a> for 746more information.</p> 747<h4><code>server.close([callback])</code><span><a class="mark" href="#tls_server_close_callback" id="tls_server_close_callback">#</a></span></h4> 748<div class="api_metadata"> 749<span>Added in: v0.3.2</span> 750</div> 751<ul> 752<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A listener callback that will be registered to listen 753for the server instance's <code>'close'</code> event.</li> 754<li>Returns: <a href="tls.html#tls_class_tls_server" class="type"><tls.Server></a></li> 755</ul> 756<p>The <code>server.close()</code> method stops the server from accepting new connections.</p> 757<p>This function operates asynchronously. The <code>'close'</code> event will be emitted 758when the server has no more open connections.</p> 759<h4><code>server.connections</code><span><a class="mark" href="#tls_server_connections" id="tls_server_connections">#</a></span></h4> 760<div class="api_metadata"> 761<span>Added in: v0.3.2</span><span>Deprecated since: v0.9.7</span> 762</div> 763<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated: Use <a href="net.html#net_server_getconnections_callback"><code>server.getConnections()</code></a> instead.</div><p></p> 764<ul> 765<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 766</ul> 767<p>Returns the current number of concurrent connections on the server.</p> 768<h4><code>server.getTicketKeys()</code><span><a class="mark" href="#tls_server_getticketkeys" id="tls_server_getticketkeys">#</a></span></h4> 769<div class="api_metadata"> 770<span>Added in: v3.0.0</span> 771</div> 772<ul> 773<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A 48-byte buffer containing the session ticket keys.</li> 774</ul> 775<p>Returns the session ticket keys.</p> 776<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 777<h4><code>server.listen()</code><span><a class="mark" href="#tls_server_listen" id="tls_server_listen">#</a></span></h4> 778<p>Starts the server listening for encrypted connections. 779This method is identical to <a href="net.html#net_server_listen"><code>server.listen()</code></a> from <a href="net.html#net_class_net_server"><code>net.Server</code></a>.</p> 780<h4><code>server.setSecureContext(options)</code><span><a class="mark" href="#tls_server_setsecurecontext_options" id="tls_server_setsecurecontext_options">#</a></span></h4> 781<div class="api_metadata"> 782<span>Added in: v11.0.0</span> 783</div> 784<ul> 785<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> An object containing any of the possible properties from 786the <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> <code>options</code> arguments (e.g. <code>key</code>, <code>cert</code>, 787<code>ca</code>, etc).</li> 788</ul> 789<p>The <code>server.setSecureContext()</code> method replaces the secure context of an 790existing server. Existing connections to the server are not interrupted.</p> 791<h4><code>server.setTicketKeys(keys)</code><span><a class="mark" href="#tls_server_setticketkeys_keys" id="tls_server_setticketkeys_keys">#</a></span></h4> 792<div class="api_metadata"> 793<span>Added in: v3.0.0</span> 794</div> 795<ul> 796<li><code>keys</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> A 48-byte buffer containing the session 797ticket keys.</li> 798</ul> 799<p>Sets the session ticket keys.</p> 800<p>Changes to the ticket keys are effective only for future server connections. 801Existing or currently pending server connections will use the previous keys.</p> 802<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 803</section><section><h3>Class: <code>tls.TLSSocket</code><span><a class="mark" href="#tls_class_tls_tlssocket" id="tls_class_tls_tlssocket">#</a></span></h3> 804<div class="api_metadata"> 805<span>Added in: v0.11.4</span> 806</div> 807<ul> 808<li>Extends: <a href="net.html#net_class_net_socket" class="type"><net.Socket></a></li> 809</ul> 810<p>Performs transparent encryption of written data and all required TLS 811negotiation.</p> 812<p>Instances of <code>tls.TLSSocket</code> implement the duplex <a href="stream.html#stream_stream">Stream</a> interface.</p> 813<p>Methods that return TLS connection metadata (e.g. 814<a href="#tls_tlssocket_getpeercertificate_detailed"><code>tls.TLSSocket.getPeerCertificate()</code></a> will only return data while the 815connection is open.</p> 816<h4><code>new tls.TLSSocket(socket[, options])</code><span><a class="mark" href="#tls_new_tls_tlssocket_socket_options" id="tls_new_tls_tlssocket_socket_options">#</a></span></h4> 817<div class="api_metadata"> 818<details class="changelog"><summary>History</summary> 819<table> 820<tbody><tr><th>Version</th><th>Changes</th></tr> 821<tr><td>v12.2.0</td> 822<td><p>The <code>enableTrace</code> option is now supported.</p></td></tr> 823<tr><td>v5.0.0</td> 824<td><p>ALPN options are supported now.</p></td></tr> 825<tr><td>v0.11.4</td> 826<td><p><span>Added in: v0.11.4</span></p></td></tr> 827</tbody></table> 828</details> 829</div> 830<ul> 831<li><code>socket</code> <a href="net.html#net_class_net_socket" class="type"><net.Socket></a> | <a href="stream.html#stream_class_stream_duplex" class="type"><stream.Duplex></a> 832On the server side, any <code>Duplex</code> stream. On the client side, any 833instance of <a href="net.html#net_class_net_socket"><code>net.Socket</code></a> (for generic <code>Duplex</code> stream support 834on the client side, <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> must be used).</li> 835<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 836<ul> 837<li><code>enableTrace</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 838<li><code>isServer</code>: The SSL/TLS protocol is asymmetrical, TLSSockets must know if 839they are to behave as a server or a client. If <code>true</code> the TLS socket will be 840instantiated as a server. <strong>Default:</strong> <code>false</code>.</li> 841<li><code>server</code> <a href="net.html#net_class_net_server" class="type"><net.Server></a> A <a href="net.html#net_class_net_server"><code>net.Server</code></a> instance.</li> 842<li><code>requestCert</code>: Whether to authenticate the remote peer by requesting a 843certificate. Clients always request a server certificate. Servers 844(<code>isServer</code> is true) may set <code>requestCert</code> to true to request a client 845certificate.</li> 846<li><code>rejectUnauthorized</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 847<li><code>ALPNProtocols</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 848<li><code>SNICallback</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 849<li><code>session</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A <code>Buffer</code> instance containing a TLS session.</li> 850<li><code>requestOCSP</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If <code>true</code>, specifies that the OCSP status request 851extension will be added to the client hello and an <code>'OCSPResponse'</code> event 852will be emitted on the socket before establishing a secure communication</li> 853<li><code>secureContext</code>: TLS context object created with 854<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. If a <code>secureContext</code> is <em>not</em> provided, one 855will be created by passing the entire <code>options</code> object to 856<code>tls.createSecureContext()</code>.</li> 857<li>...: <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> options that are used if the 858<code>secureContext</code> option is missing. Otherwise, they are ignored.</li> 859</ul> 860</li> 861</ul> 862<p>Construct a new <code>tls.TLSSocket</code> object from an existing TCP socket.</p> 863<h4>Event: <code>'keylog'</code><span><a class="mark" href="#tls_event_keylog_1" id="tls_event_keylog_1">#</a></span></h4> 864<div class="api_metadata"> 865<span>Added in: v12.3.0, v10.20.0</span> 866</div> 867<ul> 868<li><code>line</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> Line of ASCII text, in NSS <code>SSLKEYLOGFILE</code> format.</li> 869</ul> 870<p>The <code>keylog</code> event is emitted on a <code>tls.TLSSocket</code> when key material 871is generated or received by the socket. This keying material can be stored 872for debugging, as it allows captured TLS traffic to be decrypted. It may 873be emitted multiple times, before or after the handshake completes.</p> 874<p>A typical use case is to append received lines to a common text file, which 875is later used by software (such as Wireshark) to decrypt the traffic:</p> 876<pre><code class="language-js"><span class="hljs-keyword">const</span> logFile = fs.<span class="hljs-title function_">createWriteStream</span>(<span class="hljs-string">'/tmp/ssl-keys.log'</span>, { <span class="hljs-attr">flags</span>: <span class="hljs-string">'a'</span> }); 877<span class="hljs-comment">// ...</span> 878tlsSocket.<span class="hljs-title function_">on</span>(<span class="hljs-string">'keylog'</span>, <span class="hljs-function">(<span class="hljs-params">line</span>) =></span> logFile.<span class="hljs-title function_">write</span>(line));</code></pre> 879<h4>Event: <code>'OCSPResponse'</code><span><a class="mark" href="#tls_event_ocspresponse" id="tls_event_ocspresponse">#</a></span></h4> 880<div class="api_metadata"> 881<span>Added in: v0.11.13</span> 882</div> 883<p>The <code>'OCSPResponse'</code> event is emitted if the <code>requestOCSP</code> option was set 884when the <code>tls.TLSSocket</code> was created and an OCSP response has been received. 885The listener callback is passed a single argument when called:</p> 886<ul> 887<li><code>response</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The server's OCSP response</li> 888</ul> 889<p>Typically, the <code>response</code> is a digitally signed object from the server's CA that 890contains information about server's certificate revocation status.</p> 891<h4>Event: <code>'secureConnect'</code><span><a class="mark" href="#tls_event_secureconnect" id="tls_event_secureconnect">#</a></span></h4> 892<div class="api_metadata"> 893<span>Added in: v0.11.4</span> 894</div> 895<p>The <code>'secureConnect'</code> event is emitted after the handshaking process for a new 896connection has successfully completed. The listener callback will be called 897regardless of whether or not the server's certificate has been authorized. It 898is the client's responsibility to check the <code>tlsSocket.authorized</code> property to 899determine if the server certificate was signed by one of the specified CAs. If 900<code>tlsSocket.authorized === false</code>, then the error can be found by examining the 901<code>tlsSocket.authorizationError</code> property. If ALPN was used, the 902<code>tlsSocket.alpnProtocol</code> property can be checked to determine the negotiated 903protocol.</p> 904<p>The <code>'secureConnect'</code> event is not emitted when a <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a> is created 905using the <code>new tls.TLSSocket()</code> constructor.</p> 906<h4>Event: <code>'session'</code><span><a class="mark" href="#tls_event_session" id="tls_event_session">#</a></span></h4> 907<div class="api_metadata"> 908<span>Added in: v11.10.0</span> 909</div> 910<ul> 911<li><code>session</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 912</ul> 913<p>The <code>'session'</code> event is emitted on a client <code>tls.TLSSocket</code> when a new session 914or TLS ticket is available. This may or may not be before the handshake is 915complete, depending on the TLS protocol version that was negotiated. The event 916is not emitted on the server, or if a new session was not created, for example, 917when the connection was resumed. For some TLS protocol versions the event may be 918emitted multiple times, in which case all the sessions can be used for 919resumption.</p> 920<p>On the client, the <code>session</code> can be provided to the <code>session</code> option of 921<a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> to resume the connection.</p> 922<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 923<p>For TLSv1.2 and below, <a href="#tls_tlssocket_getsession"><code>tls.TLSSocket.getSession()</code></a> can be called once 924the handshake is complete. For TLSv1.3, only ticket-based resumption is allowed 925by the protocol, multiple tickets are sent, and the tickets aren't sent until 926after the handshake completes. So it is necessary to wait for the 927<code>'session'</code> event to get a resumable session. Applications 928should use the <code>'session'</code> event instead of <code>getSession()</code> to ensure 929they will work for all TLS versions. Applications that only expect to 930get or use one session should listen for this event only once:</p> 931<pre><code class="language-js">tlsSocket.<span class="hljs-title function_">once</span>(<span class="hljs-string">'session'</span>, <span class="hljs-function">(<span class="hljs-params">session</span>) =></span> { 932 <span class="hljs-comment">// The session can be used immediately or later.</span> 933 tls.<span class="hljs-title function_">connect</span>({ 934 <span class="hljs-attr">session</span>: session, 935 <span class="hljs-comment">// Other connect options...</span> 936 }); 937});</code></pre> 938<h4><code>tlsSocket.address()</code><span><a class="mark" href="#tls_tlssocket_address" id="tls_tlssocket_address">#</a></span></h4> 939<div class="api_metadata"> 940<span>Added in: v0.11.4</span> 941</div> 942<ul> 943<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 944</ul> 945<p>Returns the bound <code>address</code>, the address <code>family</code> name, and <code>port</code> of the 946underlying socket as reported by the operating system: 947<code>{ port: 12346, family: 'IPv4', address: '127.0.0.1' }</code>.</p> 948<h4><code>tlsSocket.authorizationError</code><span><a class="mark" href="#tls_tlssocket_authorizationerror" id="tls_tlssocket_authorizationerror">#</a></span></h4> 949<div class="api_metadata"> 950<span>Added in: v0.11.4</span> 951</div> 952<p>Returns the reason why the peer's certificate was not been verified. This 953property is set only when <code>tlsSocket.authorized === false</code>.</p> 954<h4><code>tlsSocket.authorized</code><span><a class="mark" href="#tls_tlssocket_authorized" id="tls_tlssocket_authorized">#</a></span></h4> 955<div class="api_metadata"> 956<span>Added in: v0.11.4</span> 957</div> 958<ul> 959<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 960</ul> 961<p>Returns <code>true</code> if the peer certificate was signed by one of the CAs specified 962when creating the <code>tls.TLSSocket</code> instance, otherwise <code>false</code>.</p> 963<h4><code>tlsSocket.disableRenegotiation()</code><span><a class="mark" href="#tls_tlssocket_disablerenegotiation" id="tls_tlssocket_disablerenegotiation">#</a></span></h4> 964<div class="api_metadata"> 965<span>Added in: v8.4.0</span> 966</div> 967<p>Disables TLS renegotiation for this <code>TLSSocket</code> instance. Once called, attempts 968to renegotiate will trigger an <code>'error'</code> event on the <code>TLSSocket</code>.</p> 969<h4><code>tlsSocket.enableTrace()</code><span><a class="mark" href="#tls_tlssocket_enabletrace" id="tls_tlssocket_enabletrace">#</a></span></h4> 970<div class="api_metadata"> 971<span>Added in: v12.2.0</span> 972</div> 973<p>When enabled, TLS packet trace information is written to <code>stderr</code>. This can be 974used to debug TLS connection problems.</p> 975<p>Note: The format of the output is identical to the output of <code>openssl s_client -trace</code> or <code>openssl s_server -trace</code>. While it is produced by OpenSSL's 976<code>SSL_trace()</code> function, the format is undocumented, can change without notice, 977and should not be relied on.</p> 978<h4><code>tlsSocket.encrypted</code><span><a class="mark" href="#tls_tlssocket_encrypted" id="tls_tlssocket_encrypted">#</a></span></h4> 979<div class="api_metadata"> 980<span>Added in: v0.11.4</span> 981</div> 982<p>Always returns <code>true</code>. This may be used to distinguish TLS sockets from regular 983<code>net.Socket</code> instances.</p> 984<h4><code>tlsSocket.getCertificate()</code><span><a class="mark" href="#tls_tlssocket_getcertificate" id="tls_tlssocket_getcertificate">#</a></span></h4> 985<div class="api_metadata"> 986<span>Added in: v11.2.0</span> 987</div> 988<ul> 989<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 990</ul> 991<p>Returns an object representing the local certificate. The returned object has 992some properties corresponding to the fields of the certificate.</p> 993<p>See <a href="#tls_tlssocket_getpeercertificate_detailed"><code>tls.TLSSocket.getPeerCertificate()</code></a> for an example of the certificate 994structure.</p> 995<p>If there is no local certificate, an empty object will be returned. If the 996socket has been destroyed, <code>null</code> will be returned.</p> 997<h4><code>tlsSocket.getCipher()</code><span><a class="mark" href="#tls_tlssocket_getcipher" id="tls_tlssocket_getcipher">#</a></span></h4> 998<div class="api_metadata"> 999<details class="changelog"><summary>History</summary> 1000<table> 1001<tbody><tr><th>Version</th><th>Changes</th></tr> 1002<tr><td>v13.4.0, v12.16.0</td> 1003<td><p>Return the IETF cipher name as <code>standardName</code>.</p></td></tr> 1004<tr><td>v12.0.0</td> 1005<td><p>Return the minimum cipher version, instead of a fixed string (<code>'TLSv1/SSLv3'</code>).</p></td></tr> 1006<tr><td>v0.11.4</td> 1007<td><p><span>Added in: v0.11.4</span></p></td></tr> 1008</tbody></table> 1009</details> 1010</div> 1011<ul> 1012<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1013<ul> 1014<li><code>name</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> OpenSSL name for the cipher suite.</li> 1015<li><code>standardName</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> IETF name for the cipher suite.</li> 1016<li><code>version</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The minimum TLS protocol version supported by this cipher 1017suite.</li> 1018</ul> 1019</li> 1020</ul> 1021<p>Returns an object containing information on the negotiated cipher suite.</p> 1022<p>For example:</p> 1023<pre><code class="language-json"><span class="hljs-punctuation">{</span> 1024 <span class="hljs-attr">"name"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"AES128-SHA256"</span><span class="hljs-punctuation">,</span> 1025 <span class="hljs-attr">"standardName"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"TLS_RSA_WITH_AES_128_CBC_SHA256"</span><span class="hljs-punctuation">,</span> 1026 <span class="hljs-attr">"version"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"TLSv1.2"</span> 1027<span class="hljs-punctuation">}</span></code></pre> 1028<p>See 1029<a href="https://www.openssl.org/docs/man1.1.1/man3/SSL_CIPHER_get_name.html">SSL_CIPHER_get_name</a> 1030for more information.</p> 1031<h4><code>tlsSocket.getEphemeralKeyInfo()</code><span><a class="mark" href="#tls_tlssocket_getephemeralkeyinfo" id="tls_tlssocket_getephemeralkeyinfo">#</a></span></h4> 1032<div class="api_metadata"> 1033<span>Added in: v5.0.0</span> 1034</div> 1035<ul> 1036<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 1037</ul> 1038<p>Returns an object representing the type, name, and size of parameter of 1039an ephemeral key exchange in <a href="#tls_perfect_forward_secrecy">perfect forward secrecy</a> on a client 1040connection. It returns an empty object when the key exchange is not 1041ephemeral. As this is only supported on a client socket; <code>null</code> is returned 1042if called on a server socket. The supported types are <code>'DH'</code> and <code>'ECDH'</code>. The 1043<code>name</code> property is available only when type is <code>'ECDH'</code>.</p> 1044<p>For example: <code>{ type: 'ECDH', name: 'prime256v1', size: 256 }</code>.</p> 1045<h4><code>tlsSocket.getFinished()</code><span><a class="mark" href="#tls_tlssocket_getfinished" id="tls_tlssocket_getfinished">#</a></span></h4> 1046<div class="api_metadata"> 1047<span>Added in: v9.9.0</span> 1048</div> 1049<ul> 1050<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#Undefined_type" class="type"><undefined></a> The latest <code>Finished</code> message that has been 1051sent to the socket as part of a SSL/TLS handshake, or <code>undefined</code> if 1052no <code>Finished</code> message has been sent yet.</li> 1053</ul> 1054<p>As the <code>Finished</code> messages are message digests of the complete handshake 1055(with a total of 192 bits for TLS 1.0 and more for SSL 3.0), they can 1056be used for external authentication procedures when the authentication 1057provided by SSL/TLS is not desired or is not enough.</p> 1058<p>Corresponds to the <code>SSL_get_finished</code> routine in OpenSSL and may be used 1059to implement the <code>tls-unique</code> channel binding from <a href="https://tools.ietf.org/html/rfc5929">RFC 5929</a>.</p> 1060<h4><code>tlsSocket.getPeerCertificate([detailed])</code><span><a class="mark" href="#tls_tlssocket_getpeercertificate_detailed" id="tls_tlssocket_getpeercertificate_detailed">#</a></span></h4> 1061<div class="api_metadata"> 1062<span>Added in: v0.11.4</span> 1063</div> 1064<ul> 1065<li><code>detailed</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Include the full certificate chain if <code>true</code>, otherwise 1066include just the peer's certificate.</li> 1067<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> A certificate object.</li> 1068</ul> 1069<p>Returns an object representing the peer's certificate. If the peer does not 1070provide a certificate, an empty object will be returned. If the socket has been 1071destroyed, <code>null</code> will be returned.</p> 1072<p>If the full certificate chain was requested, each certificate will include an 1073<code>issuerCertificate</code> property containing an object representing its issuer's 1074certificate.</p> 1075<h5>Certificate object<span><a class="mark" href="#tls_certificate_object" id="tls_certificate_object">#</a></span></h5> 1076<div class="api_metadata"> 1077<details class="changelog"><summary>History</summary> 1078<table> 1079<tbody><tr><th>Version</th><th>Changes</th></tr> 1080<tr><td>v11.4.0</td> 1081<td><p>Support Elliptic Curve public key info.</p></td></tr> 1082</tbody></table> 1083</details> 1084</div> 1085<p>A certificate object has properties corresponding to the fields of the 1086certificate.</p> 1087<ul> 1088<li><code>raw</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The DER encoded X.509 certificate data.</li> 1089<li><code>subject</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> The certificate subject, described in terms of 1090Country (<code>C:</code>), StateOrProvince (<code>ST</code>), Locality (<code>L</code>), Organization (<code>O</code>), 1091OrganizationalUnit (<code>OU</code>), and CommonName (<code>CN</code>). The CommonName is typically 1092a DNS name with TLS certificates. Example: 1093<code>{C: 'UK', ST: 'BC', L: 'Metro', O: 'Node Fans', OU: 'Docs', CN: 'example.com'}</code>.</li> 1094<li><code>issuer</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> The certificate issuer, described in the same terms as the 1095<code>subject</code>.</li> 1096<li><code>valid_from</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The date-time the certificate is valid from.</li> 1097<li><code>valid_to</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The date-time the certificate is valid to.</li> 1098<li><code>serialNumber</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The certificate serial number, as a hex string. 1099Example: <code>'B9B0D332A1AA5635'</code>.</li> 1100<li><code>fingerprint</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The SHA-1 digest of the DER encoded certificate. It is 1101returned as a <code>:</code> separated hexadecimal string. Example: <code>'2A:7A:C2:DD:...'</code>.</li> 1102<li><code>fingerprint256</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The SHA-256 digest of the DER encoded certificate. 1103It is returned as a <code>:</code> separated hexadecimal string. Example: 1104<code>'2A:7A:C2:DD:...'</code>.</li> 1105<li><code>ext_key_usage</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array" class="type"><Array></a> (Optional) The extended key usage, a set of OIDs.</li> 1106<li><code>subjectaltname</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> (Optional) A string containing concatenated names 1107for the subject, an alternative to the <code>subject</code> names.</li> 1108<li><code>infoAccess</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array" class="type"><Array></a> (Optional) An array describing the AuthorityInfoAccess, 1109used with OCSP.</li> 1110<li><code>issuerCertificate</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> (Optional) The issuer certificate object. For 1111self-signed certificates, this may be a circular reference.</li> 1112</ul> 1113<p>The certificate may contain information about the public key, depending on 1114the key type.</p> 1115<p>For RSA keys, the following properties may be defined:</p> 1116<ul> 1117<li><code>bits</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The RSA bit size. Example: <code>1024</code>.</li> 1118<li><code>exponent</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The RSA exponent, as a string in hexadecimal number 1119notation. Example: <code>'0x010001'</code>.</li> 1120<li><code>modulus</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The RSA modulus, as a hexadecimal string. Example: 1121<code>'B56CE45CB7...'</code>.</li> 1122<li><code>pubkey</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The public key.</li> 1123</ul> 1124<p>For EC keys, the following properties may be defined:</p> 1125<ul> 1126<li><code>pubkey</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The public key.</li> 1127<li><code>bits</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The key size in bits. Example: <code>256</code>.</li> 1128<li><code>asn1Curve</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> (Optional) The ASN.1 name of the OID of the elliptic 1129curve. Well-known curves are identified by an OID. While it is unusual, it is 1130possible that the curve is identified by its mathematical properties, in which 1131case it will not have an OID. Example: <code>'prime256v1'</code>.</li> 1132<li><code>nistCurve</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> (Optional) The NIST name for the elliptic curve, if it 1133has one (not all well-known curves have been assigned names by NIST). Example: 1134<code>'P-256'</code>.</li> 1135</ul> 1136<p>Example certificate:</p> 1137<!-- eslint-skip --> 1138<pre><code class="language-js">{ <span class="hljs-attr">subject</span>: 1139 { <span class="hljs-attr">OU</span>: [ <span class="hljs-string">'Domain Control Validated'</span>, <span class="hljs-string">'PositiveSSL Wildcard'</span> ], 1140 <span class="hljs-attr">CN</span>: <span class="hljs-string">'*.nodejs.org'</span> }, 1141 <span class="hljs-attr">issuer</span>: 1142 { <span class="hljs-attr">C</span>: <span class="hljs-string">'GB'</span>, 1143 <span class="hljs-attr">ST</span>: <span class="hljs-string">'Greater Manchester'</span>, 1144 <span class="hljs-attr">L</span>: <span class="hljs-string">'Salford'</span>, 1145 <span class="hljs-attr">O</span>: <span class="hljs-string">'COMODO CA Limited'</span>, 1146 <span class="hljs-attr">CN</span>: <span class="hljs-string">'COMODO RSA Domain Validation Secure Server CA'</span> }, 1147 <span class="hljs-attr">subjectaltname</span>: <span class="hljs-string">'DNS:*.nodejs.org, DNS:nodejs.org'</span>, 1148 <span class="hljs-attr">infoAccess</span>: 1149 { <span class="hljs-string">'CA Issuers - URI'</span>: 1150 [ <span class="hljs-string">'http://crt.comodoca.com/COMODORSADomainValidationSecureServerCA.crt'</span> ], 1151 <span class="hljs-string">'OCSP - URI'</span>: [ <span class="hljs-string">'http://ocsp.comodoca.com'</span> ] }, 1152 <span class="hljs-attr">modulus</span>: <span class="hljs-string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span>, 1153 <span class="hljs-attr">exponent</span>: <span class="hljs-string">'0x10001'</span>, 1154 <span class="hljs-attr">pubkey</span>: <Buffer ... >, 1155 valid_from: 'Aug 14 00:00:00 2017 GMT', 1156 valid_to: 'Nov 20 23:59:59 2019 GMT', 1157 fingerprint: '01:02:59:D9:C3:D2:0D:08:F7:82:4E:44:A4:B4:53:C5:E2:3A:87:4D', 1158 fingerprint256: '69:AE:1A:6A:D4:3D:C6:C1:1B:EA:C6:23:DE:BA:2A:14:62:62:93:5C:7A:EA:06:41:9B:0B:BC:87:CE:48:4E:02', 1159 ext_key_usage: [ '1.3.6.1.5.5.7.3.1', '1.3.6.1.5.5.7.3.2' ], 1160 serialNumber: '66593D57F20CBC573E433381B5FEC280', 1161 raw: <Buffer ... > }</code></pre> 1162<h4><code>tlsSocket.getPeerFinished()</code><span><a class="mark" href="#tls_tlssocket_getpeerfinished" id="tls_tlssocket_getpeerfinished">#</a></span></h4> 1163<div class="api_metadata"> 1164<span>Added in: v9.9.0</span> 1165</div> 1166<ul> 1167<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#Undefined_type" class="type"><undefined></a> The latest <code>Finished</code> message that is expected 1168or has actually been received from the socket as part of a SSL/TLS handshake, 1169or <code>undefined</code> if there is no <code>Finished</code> message so far.</li> 1170</ul> 1171<p>As the <code>Finished</code> messages are message digests of the complete handshake 1172(with a total of 192 bits for TLS 1.0 and more for SSL 3.0), they can 1173be used for external authentication procedures when the authentication 1174provided by SSL/TLS is not desired or is not enough.</p> 1175<p>Corresponds to the <code>SSL_get_peer_finished</code> routine in OpenSSL and may be used 1176to implement the <code>tls-unique</code> channel binding from <a href="https://tools.ietf.org/html/rfc5929">RFC 5929</a>.</p> 1177<h4><code>tlsSocket.getProtocol()</code><span><a class="mark" href="#tls_tlssocket_getprotocol" id="tls_tlssocket_getprotocol">#</a></span></h4> 1178<div class="api_metadata"> 1179<span>Added in: v5.7.0</span> 1180</div> 1181<ul> 1182<li>Returns: <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></li> 1183</ul> 1184<p>Returns a string containing the negotiated SSL/TLS protocol version of the 1185current connection. The value <code>'unknown'</code> will be returned for connected 1186sockets that have not completed the handshaking process. The value <code>null</code> will 1187be returned for server sockets or disconnected client sockets.</p> 1188<p>Protocol versions are:</p> 1189<ul> 1190<li><code>'SSLv3'</code></li> 1191<li><code>'TLSv1'</code></li> 1192<li><code>'TLSv1.1'</code></li> 1193<li><code>'TLSv1.2'</code></li> 1194<li><code>'TLSv1.3'</code></li> 1195</ul> 1196<p>See the OpenSSL <a href="https://www.openssl.org/docs/man1.1.1/man3/SSL_get_version.html"><code>SSL_get_version</code></a> documentation for more information.</p> 1197<h4><code>tlsSocket.getSession()</code><span><a class="mark" href="#tls_tlssocket_getsession" id="tls_tlssocket_getsession">#</a></span></h4> 1198<div class="api_metadata"> 1199<span>Added in: v0.11.4</span> 1200</div> 1201<ul> 1202<li><a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 1203</ul> 1204<p>Returns the TLS session data or <code>undefined</code> if no session was 1205negotiated. On the client, the data can be provided to the <code>session</code> option of 1206<a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> to resume the connection. On the server, it may be useful 1207for debugging.</p> 1208<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 1209<p>Note: <code>getSession()</code> works only for TLSv1.2 and below. For TLSv1.3, applications 1210must use the <a href="#tls_event_session"><code>'session'</code></a> event (it also works for TLSv1.2 and below).</p> 1211<h4><code>tlsSocket.getSharedSigalgs()</code><span><a class="mark" href="#tls_tlssocket_getsharedsigalgs" id="tls_tlssocket_getsharedsigalgs">#</a></span></h4> 1212<div class="api_metadata"> 1213<span>Added in: v12.11.0</span> 1214</div> 1215<ul> 1216<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array" class="type"><Array></a> List of signature algorithms shared between the server and 1217the client in the order of decreasing preference.</li> 1218</ul> 1219<p>See 1220<a href="https://www.openssl.org/docs/man1.1.1/man3/SSL_get_shared_sigalgs.html">SSL_get_shared_sigalgs</a> 1221for more information.</p> 1222<h4><code>tlsSocket.exportKeyingMaterial(length, label[, context])</code><span><a class="mark" href="#tls_tlssocket_exportkeyingmaterial_length_label_context" id="tls_tlssocket_exportkeyingmaterial_length_label_context">#</a></span></h4> 1223<div class="api_metadata"> 1224<span>Added in: v13.10.0</span> 1225</div> 1226<ul> 1227<li> 1228<p><code>length</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> number of bytes to retrieve from keying material</p> 1229</li> 1230<li> 1231<p><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> an application specific label, typically this will be a 1232value from the 1233<a href="https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#exporter-labels">IANA Exporter Label Registry</a>.</p> 1234</li> 1235<li> 1236<p><code>context</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> Optionally provide a context.</p> 1237</li> 1238<li> 1239<p>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> requested bytes of the keying material</p> 1240</li> 1241</ul> 1242<p>Keying material is used for validations to prevent different kind of attacks in 1243network protocols, for example in the specifications of IEEE 802.1X.</p> 1244<p>Example</p> 1245<pre><code class="language-js"><span class="hljs-keyword">const</span> keyingMaterial = tlsSocket.<span class="hljs-title function_">exportKeyingMaterial</span>( 1246 <span class="hljs-number">128</span>, 1247 <span class="hljs-string">'client finished'</span>); 1248 1249<span class="hljs-comment">/** 1250 Example return value of keyingMaterial: 1251 <Buffer 76 26 af 99 c5 56 8e 42 09 91 ef 9f 93 cb ad 6c 7b 65 f8 53 f1 d8 d9 1252 12 5a 33 b8 b5 25 df 7b 37 9f e0 e2 4f b8 67 83 a3 2f cd 5d 41 42 4c 91 1253 74 ef 2c ... 78 more bytes> 1254*/</span></code></pre> 1255<p>See the OpenSSL <a href="https://www.openssl.org/docs/man1.1.1/man3/SSL_export_keying_material.html"><code>SSL_export_keying_material</code></a> documentation for more 1256information.</p> 1257<h4><code>tlsSocket.getTLSTicket()</code><span><a class="mark" href="#tls_tlssocket_gettlsticket" id="tls_tlssocket_gettlsticket">#</a></span></h4> 1258<div class="api_metadata"> 1259<span>Added in: v0.11.4</span> 1260</div> 1261<ul> 1262<li><a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 1263</ul> 1264<p>For a client, returns the TLS session ticket if one is available, or 1265<code>undefined</code>. For a server, always returns <code>undefined</code>.</p> 1266<p>It may be useful for debugging.</p> 1267<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 1268<h4><code>tlsSocket.isSessionReused()</code><span><a class="mark" href="#tls_tlssocket_issessionreused" id="tls_tlssocket_issessionreused">#</a></span></h4> 1269<div class="api_metadata"> 1270<span>Added in: v0.5.6</span> 1271</div> 1272<ul> 1273<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 session was reused, <code>false</code> otherwise.</li> 1274</ul> 1275<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 1276<h4><code>tlsSocket.localAddress</code><span><a class="mark" href="#tls_tlssocket_localaddress" id="tls_tlssocket_localaddress">#</a></span></h4> 1277<div class="api_metadata"> 1278<span>Added in: v0.11.4</span> 1279</div> 1280<ul> 1281<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1282</ul> 1283<p>Returns the string representation of the local IP address.</p> 1284<h4><code>tlsSocket.localPort</code><span><a class="mark" href="#tls_tlssocket_localport" id="tls_tlssocket_localport">#</a></span></h4> 1285<div class="api_metadata"> 1286<span>Added in: v0.11.4</span> 1287</div> 1288<ul> 1289<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 1290</ul> 1291<p>Returns the numeric representation of the local port.</p> 1292<h4><code>tlsSocket.remoteAddress</code><span><a class="mark" href="#tls_tlssocket_remoteaddress" id="tls_tlssocket_remoteaddress">#</a></span></h4> 1293<div class="api_metadata"> 1294<span>Added in: v0.11.4</span> 1295</div> 1296<ul> 1297<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1298</ul> 1299<p>Returns the string representation of the remote IP address. For example, 1300<code>'74.125.127.100'</code> or <code>'2001:4860:a005::68'</code>.</p> 1301<h4><code>tlsSocket.remoteFamily</code><span><a class="mark" href="#tls_tlssocket_remotefamily" id="tls_tlssocket_remotefamily">#</a></span></h4> 1302<div class="api_metadata"> 1303<span>Added in: v0.11.4</span> 1304</div> 1305<ul> 1306<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1307</ul> 1308<p>Returns the string representation of the remote IP family. <code>'IPv4'</code> or <code>'IPv6'</code>.</p> 1309<h4><code>tlsSocket.remotePort</code><span><a class="mark" href="#tls_tlssocket_remoteport" id="tls_tlssocket_remoteport">#</a></span></h4> 1310<div class="api_metadata"> 1311<span>Added in: v0.11.4</span> 1312</div> 1313<ul> 1314<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 1315</ul> 1316<p>Returns the numeric representation of the remote port. For example, <code>443</code>.</p> 1317<h4><code>tlsSocket.renegotiate(options, callback)</code><span><a class="mark" href="#tls_tlssocket_renegotiate_options_callback" id="tls_tlssocket_renegotiate_options_callback">#</a></span></h4> 1318<div class="api_metadata"> 1319<span>Added in: v0.11.8</span> 1320</div> 1321<ul> 1322<li> 1323<p><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></p> 1324<ul> 1325<li><code>rejectUnauthorized</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If not <code>false</code>, the server certificate is 1326verified against the list of supplied CAs. An <code>'error'</code> event is emitted if 1327verification fails; <code>err.code</code> contains the OpenSSL error code. <strong>Default:</strong> 1328<code>true</code>.</li> 1329<li><code>requestCert</code></li> 1330</ul> 1331</li> 1332<li> 1333<p><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> If <code>renegotiate()</code> returned <code>true</code>, callback is 1334attached once to the <code>'secure'</code> event. If <code>renegotiate()</code> returned <code>false</code>, 1335<code>callback</code> will be called in the next tick with an error, unless the 1336<code>tlsSocket</code> has been destroyed, in which case <code>callback</code> will not be called 1337at all.</p> 1338</li> 1339<li> 1340<p>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> if renegotiation was initiated, <code>false</code> otherwise.</p> 1341</li> 1342</ul> 1343<p>The <code>tlsSocket.renegotiate()</code> method initiates a TLS renegotiation process. 1344Upon completion, the <code>callback</code> function will be passed a single argument 1345that is either an <code>Error</code> (if the request failed) or <code>null</code>.</p> 1346<p>This method can be used to request a peer's certificate after the secure 1347connection has been established.</p> 1348<p>When running as the server, the socket will be destroyed with an error after 1349<code>handshakeTimeout</code> timeout.</p> 1350<p>For TLSv1.3, renegotiation cannot be initiated, it is not supported by the 1351protocol.</p> 1352<h4><code>tlsSocket.setMaxSendFragment(size)</code><span><a class="mark" href="#tls_tlssocket_setmaxsendfragment_size" id="tls_tlssocket_setmaxsendfragment_size">#</a></span></h4> 1353<div class="api_metadata"> 1354<span>Added in: v0.11.11</span> 1355</div> 1356<ul> 1357<li><code>size</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The maximum TLS fragment size. The maximum value is <code>16384</code>. 1358<strong>Default:</strong> <code>16384</code>.</li> 1359<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 1360</ul> 1361<p>The <code>tlsSocket.setMaxSendFragment()</code> method sets the maximum TLS fragment size. 1362Returns <code>true</code> if setting the limit succeeded; <code>false</code> otherwise.</p> 1363<p>Smaller fragment sizes decrease the buffering latency on the client: larger 1364fragments are buffered by the TLS layer until the entire fragment is received 1365and its integrity is verified; large fragments can span multiple roundtrips 1366and their processing can be delayed due to packet loss or reordering. However, 1367smaller fragments add extra TLS framing bytes and CPU overhead, which may 1368decrease overall server throughput.</p> 1369</section><section><h3><code>tls.checkServerIdentity(hostname, cert)</code><span><a class="mark" href="#tls_tls_checkserveridentity_hostname_cert" id="tls_tls_checkserveridentity_hostname_cert">#</a></span></h3> 1370<div class="api_metadata"> 1371<details class="changelog"><summary>History</summary> 1372<table> 1373<tbody><tr><th>Version</th><th>Changes</th></tr> 1374<tr><td>v14.18.3</td> 1375<td><p>Support for <code>uniformResourceIdentifier</code> subject alternative names has been disabled in response to CVE-2021-44531.</p></td></tr> 1376<tr><td>v0.8.4</td> 1377<td><p><span>Added in: v0.8.4</span></p></td></tr> 1378</tbody></table> 1379</details> 1380</div> 1381<ul> 1382<li><code>hostname</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The host name or IP address to verify the certificate 1383against.</li> 1384<li><code>cert</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> A <a href="#tls_certificate_object">certificate object</a> representing the peer's certificate.</li> 1385<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type" class="type"><undefined></a></li> 1386</ul> 1387<p>Verifies the certificate <code>cert</code> is issued to <code>hostname</code>.</p> 1388<p>Returns <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a> object, populating it with <code>reason</code>, <code>host</code>, and <code>cert</code> on 1389failure. On success, returns <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type" class="type"><undefined></a>.</p> 1390<p>This function can be overwritten by providing alternative function as part of 1391the <code>options.checkServerIdentity</code> option passed to <code>tls.connect()</code>. The 1392overwriting function can call <code>tls.checkServerIdentity()</code> of course, to augment 1393the checks done with additional verification.</p> 1394<p>This function is only called if the certificate passed all other checks, such as 1395being issued by trusted CA (<code>options.ca</code>).</p> 1396<p>Earlier versions of Node.js incorrectly accepted certificates for a given 1397<code>hostname</code> if a matching <code>uniformResourceIdentifier</code> subject alternative name 1398was present (see <a href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44531">CVE-2021-44531</a>). Applications that wish to accept 1399<code>uniformResourceIdentifier</code> subject alternative names can use a custom 1400<code>options.checkServerIdentity</code> function that implements the desired behavior.</p> 1401</section><section><h3><code>tls.connect(options[, callback])</code><span><a class="mark" href="#tls_tls_connect_options_callback" id="tls_tls_connect_options_callback">#</a></span></h3> 1402<div class="api_metadata"> 1403<details class="changelog"><summary>History</summary> 1404<table> 1405<tbody><tr><th>Version</th><th>Changes</th></tr> 1406<tr><td>v14.18.0</td> 1407<td><p>Added <code>onread</code> option.</p></td></tr> 1408<tr><td>v14.1.0</td> 1409<td><p>The <code>highWaterMark</code> option is accepted now.</p></td></tr> 1410<tr><td>v13.6.0, v12.16.0</td> 1411<td><p>The <code>pskCallback</code> option is now supported.</p></td></tr> 1412<tr><td>v12.9.0</td> 1413<td><p>Support the <code>allowHalfOpen</code> option.</p></td></tr> 1414<tr><td>v12.4.0</td> 1415<td><p>The <code>hints</code> option is now supported.</p></td></tr> 1416<tr><td>v12.2.0</td> 1417<td><p>The <code>enableTrace</code> option is now supported.</p></td></tr> 1418<tr><td>v11.8.0, v10.16.0</td> 1419<td><p>The <code>timeout</code> option is supported now.</p></td></tr> 1420<tr><td>v8.0.0</td> 1421<td><p>The <code>lookup</code> option is supported now.</p></td></tr> 1422<tr><td>v8.0.0</td> 1423<td><p>The <code>ALPNProtocols</code> option can be a <code>TypedArray</code> or <code>DataView</code> now.</p></td></tr> 1424<tr><td>v5.0.0</td> 1425<td><p>ALPN options are supported now.</p></td></tr> 1426<tr><td>v5.3.0, v4.7.0</td> 1427<td><p>The <code>secureContext</code> option is supported now.</p></td></tr> 1428<tr><td>v0.11.3</td> 1429<td><p><span>Added in: v0.11.3</span></p></td></tr> 1430</tbody></table> 1431</details> 1432</div> 1433<ul> 1434<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1435<ul> 1436<li><code>enableTrace</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1437<li><code>host</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Host the client should connect to. <strong>Default:</strong> 1438<code>'localhost'</code>.</li> 1439<li><code>port</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Port the client should connect to.</li> 1440<li><code>path</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Creates Unix socket connection to path. If this option is 1441specified, <code>host</code> and <code>port</code> are ignored.</li> 1442<li><code>socket</code> <a href="stream.html#stream_class_stream_duplex" class="type"><stream.Duplex></a> Establish secure connection on a given socket 1443rather than creating a new socket. Typically, this is an instance of 1444<a href="net.html#net_class_net_socket"><code>net.Socket</code></a>, but any <code>Duplex</code> stream is allowed. 1445If this option is specified, <code>path</code>, <code>host</code> and <code>port</code> are ignored, 1446except for certificate validation. Usually, a socket is already connected 1447when passed to <code>tls.connect()</code>, but it can be connected later. 1448Connection/disconnection/destruction of <code>socket</code> is the user's 1449responsibility; calling <code>tls.connect()</code> will not cause <code>net.connect()</code> to be 1450called.</li> 1451<li><code>allowHalfOpen</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If set to <code>false</code>, then the socket will 1452automatically end the writable side when the readable side ends. If the 1453<code>socket</code> option is set, this option has no effect. See the <code>allowHalfOpen</code> 1454option of <a href="net.html#net_class_net_socket"><code>net.Socket</code></a> for details. <strong>Default:</strong> <code>false</code>.</li> 1455<li><code>rejectUnauthorized</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If not <code>false</code>, the server certificate is 1456verified against the list of supplied CAs. An <code>'error'</code> event is emitted if 1457verification fails; <code>err.code</code> contains the OpenSSL error code. <strong>Default:</strong> 1458<code>true</code>.</li> 1459<li><code>pskCallback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 1460<ul> 1461<li>hint: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> optional message sent from the server to help client 1462decide which identity to use during negotiation. 1463Always <code>null</code> if TLS 1.3 is used.</li> 1464<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> in the form 1465<code>{ psk: <Buffer|TypedArray|DataView>, identity: <string> }</code> 1466or <code>null</code> to stop the negotiation process. <code>psk</code> must be 1467compatible with the selected cipher's digest. 1468<code>identity</code> must use UTF-8 encoding.</li> 1469</ul> 1470When negotiating TLS-PSK (pre-shared keys), this function is called 1471with optional identity <code>hint</code> provided by the server or <code>null</code> 1472in case of TLS 1.3 where <code>hint</code> was removed. 1473It will be necessary to provide a custom <code>tls.checkServerIdentity()</code> 1474for the connection as the default one will try to check host name/IP 1475of the server against the certificate but that's not applicable for PSK 1476because there won't be a certificate present. 1477More information can be found in the <a href="https://tools.ietf.org/html/rfc4279">RFC 4279</a>.</li> 1478<li><code>ALPNProtocols</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="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> 1479An array of strings, <code>Buffer</code>s or <code>TypedArray</code>s or <code>DataView</code>s, or a 1480single <code>Buffer</code> or <code>TypedArray</code> or <code>DataView</code> containing the supported ALPN 1481protocols. <code>Buffer</code>s should have the format <code>[len][name][len][name]...</code> 1482e.g. <code>'\x08http/1.1\x08http/1.0'</code>, where the <code>len</code> byte is the length of the 1483next protocol name. Passing an array is usually much simpler, e.g. 1484<code>['http/1.1', 'http/1.0']</code>. Protocols earlier in the list have higher 1485preference than those later.</li> 1486<li><code>servername</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Server name for the SNI (Server Name Indication) TLS 1487extension. It is the name of the host being connected to, and must be a host 1488name, and not an IP address. It can be used by a multi-homed server to 1489choose the correct certificate to present to the client, see the 1490<code>SNICallback</code> option to <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>.</li> 1491<li><code>checkServerIdentity(servername, cert)</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A callback function 1492to be used (instead of the builtin <code>tls.checkServerIdentity()</code> function) 1493when checking the server's host name (or the provided <code>servername</code> when 1494explicitly set) against the certificate. This should return an <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a> if 1495verification fails. The method should return <code>undefined</code> if the <code>servername</code> 1496and <code>cert</code> are verified.</li> 1497<li><code>session</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A <code>Buffer</code> instance, containing TLS session.</li> 1498<li><code>minDHSize</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Minimum size of the DH parameter in bits to accept a 1499TLS connection. When a server offers a DH parameter with a size less 1500than <code>minDHSize</code>, the TLS connection is destroyed and an error is thrown. 1501<strong>Default:</strong> <code>1024</code>.</li> 1502<li><code>highWaterMark</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Consistent with the readable stream <code>highWaterMark</code> parameter. 1503<strong>Default:</strong> <code>16 * 1024</code>.</li> 1504<li><code>secureContext</code>: TLS context object created with 1505<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. If a <code>secureContext</code> is <em>not</em> provided, one 1506will be created by passing the entire <code>options</code> object to 1507<code>tls.createSecureContext()</code>.</li> 1508<li><code>onread</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> If the <code>socket</code> option is missing, incoming data is 1509stored in a single <code>buffer</code> and passed to the supplied <code>callback</code> when 1510data arrives on the socket, otherwise the option is ignored. See the 1511<code>onread</code> option of <a href="net.html#net_class_net_socket"><code>net.Socket</code></a> for details.</li> 1512<li>...: <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> options that are used if the 1513<code>secureContext</code> option is missing, otherwise they are ignored.</li> 1514<li>...: Any <a href="net.html#net_socket_connect_options_connectlistener"><code>socket.connect()</code></a> option not already listed.</li> 1515</ul> 1516</li> 1517<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1518<li>Returns: <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a></li> 1519</ul> 1520<p>The <code>callback</code> function, if specified, will be added as a listener for the 1521<a href="#tls_event_secureconnect"><code>'secureConnect'</code></a> event.</p> 1522<p><code>tls.connect()</code> returns a <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a> object.</p> 1523<p>Unlike the <code>https</code> API, <code>tls.connect()</code> does not enable the 1524SNI (Server Name Indication) extension by default, which may cause some 1525servers to return an incorrect certificate or reject the connection 1526altogether. To enable SNI, set the <code>servername</code> option in addition 1527to <code>host</code>.</p> 1528<p>The following illustrates a client for the echo server example from 1529<a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>:</p> 1530<pre><code class="language-js"><span class="hljs-comment">// Assumes an echo server that is listening on port 8000.</span> 1531<span class="hljs-keyword">const</span> tls = <span class="hljs-built_in">require</span>(<span class="hljs-string">'tls'</span>); 1532<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 1533 1534<span class="hljs-keyword">const</span> options = { 1535 <span class="hljs-comment">// Necessary only if the server requires client certificate authentication.</span> 1536 <span class="hljs-attr">key</span>: fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'client-key.pem'</span>), 1537 <span class="hljs-attr">cert</span>: fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'client-cert.pem'</span>), 1538 1539 <span class="hljs-comment">// Necessary only if the server uses a self-signed certificate.</span> 1540 <span class="hljs-attr">ca</span>: [ fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'server-cert.pem'</span>) ], 1541 1542 <span class="hljs-comment">// Necessary only if the server's cert isn't for "localhost".</span> 1543 <span class="hljs-attr">checkServerIdentity</span>: <span class="hljs-function">() =></span> { <span class="hljs-keyword">return</span> <span class="hljs-literal">null</span>; }, 1544}; 1545 1546<span class="hljs-keyword">const</span> socket = tls.<span class="hljs-title function_">connect</span>(<span class="hljs-number">8000</span>, options, <span class="hljs-function">() =></span> { 1547 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'client connected'</span>, 1548 socket.<span class="hljs-property">authorized</span> ? <span class="hljs-string">'authorized'</span> : <span class="hljs-string">'unauthorized'</span>); 1549 process.<span class="hljs-property">stdin</span>.<span class="hljs-title function_">pipe</span>(socket); 1550 process.<span class="hljs-property">stdin</span>.<span class="hljs-title function_">resume</span>(); 1551}); 1552socket.<span class="hljs-title function_">setEncoding</span>(<span class="hljs-string">'utf8'</span>); 1553socket.<span class="hljs-title function_">on</span>(<span class="hljs-string">'data'</span>, <span class="hljs-function">(<span class="hljs-params">data</span>) =></span> { 1554 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(data); 1555}); 1556socket.<span class="hljs-title function_">on</span>(<span class="hljs-string">'end'</span>, <span class="hljs-function">() =></span> { 1557 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'server ends connection'</span>); 1558});</code></pre> 1559</section><section><h3><code>tls.connect(path[, options][, callback])</code><span><a class="mark" href="#tls_tls_connect_path_options_callback" id="tls_tls_connect_path_options_callback">#</a></span></h3> 1560<div class="api_metadata"> 1561<span>Added in: v0.11.3</span> 1562</div> 1563<ul> 1564<li><code>path</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Default value for <code>options.path</code>.</li> 1565<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> See <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a>.</li> 1566<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> See <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a>.</li> 1567<li>Returns: <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a></li> 1568</ul> 1569<p>Same as <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> except that <code>path</code> can be provided 1570as an argument instead of an option.</p> 1571<p>A path option, if specified, will take precedence over the path argument.</p> 1572</section><section><h3><code>tls.connect(port[, host][, options][, callback])</code><span><a class="mark" href="#tls_tls_connect_port_host_options_callback" id="tls_tls_connect_port_host_options_callback">#</a></span></h3> 1573<div class="api_metadata"> 1574<span>Added in: v0.11.3</span> 1575</div> 1576<ul> 1577<li><code>port</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Default value for <code>options.port</code>.</li> 1578<li><code>host</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Default value for <code>options.host</code>.</li> 1579<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> See <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a>.</li> 1580<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> See <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a>.</li> 1581<li>Returns: <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a></li> 1582</ul> 1583<p>Same as <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> except that <code>port</code> and <code>host</code> can be provided 1584as arguments instead of options.</p> 1585<p>A port or host option, if specified, will take precedence over any port or host 1586argument.</p> 1587</section><section><h3><code>tls.createSecureContext([options])</code><span><a class="mark" href="#tls_tls_createsecurecontext_options" id="tls_tls_createsecurecontext_options">#</a></span></h3> 1588<div class="api_metadata"> 1589<details class="changelog"><summary>History</summary> 1590<table> 1591<tbody><tr><th>Version</th><th>Changes</th></tr> 1592<tr><td>v12.12.0</td> 1593<td><p>Added <code>privateKeyIdentifier</code> and <code>privateKeyEngine</code> options to get private key from an OpenSSL engine.</p></td></tr> 1594<tr><td>v12.11.0</td> 1595<td><p>Added <code>sigalgs</code> option to override supported signature algorithms.</p></td></tr> 1596<tr><td>v12.0.0</td> 1597<td><p>TLSv1.3 support added.</p></td></tr> 1598<tr><td>v11.5.0</td> 1599<td><p>The <code>ca:</code> option now supports <code>BEGIN TRUSTED CERTIFICATE</code>.</p></td></tr> 1600<tr><td>v11.4.0, v10.16.0</td> 1601<td><p>The <code>minVersion</code> and <code>maxVersion</code> can be used to restrict the allowed TLS protocol versions.</p></td></tr> 1602<tr><td>v10.0.0</td> 1603<td><p>The <code>ecdhCurve</code> cannot be set to <code>false</code> anymore due to a change in OpenSSL.</p></td></tr> 1604<tr><td>v9.3.0</td> 1605<td><p>The <code>options</code> parameter can now include <code>clientCertEngine</code>.</p></td></tr> 1606<tr><td>v9.0.0</td> 1607<td><p>The <code>ecdhCurve</code> option can now be multiple <code>':'</code> separated curve names or <code>'auto'</code>.</p></td></tr> 1608<tr><td>v7.3.0</td> 1609<td><p>If the <code>key</code> option is an array, individual entries do not need a <code>passphrase</code> property anymore. <code>Array</code> entries can also just be <code>string</code>s or <code>Buffer</code>s now.</p></td></tr> 1610<tr><td>v5.2.0</td> 1611<td><p>The <code>ca</code> option can now be a single string containing multiple CA certificates.</p></td></tr> 1612<tr><td>v0.11.13</td> 1613<td><p><span>Added in: v0.11.13</span></p></td></tr> 1614</tbody></table> 1615</details> 1616</div> 1617<ul> 1618<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1619<ul> 1620<li><code>ca</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#String_type" class="type"><string[]></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer[]></a> Optionally override the trusted CA 1621certificates. Default is to trust the well-known CAs curated by Mozilla. 1622Mozilla's CAs are completely replaced when CAs are explicitly specified 1623using this option. The value can be a string or <code>Buffer</code>, or an <code>Array</code> of 1624strings and/or <code>Buffer</code>s. Any string or <code>Buffer</code> can contain multiple PEM 1625CAs concatenated together. The peer's certificate must be chainable to a CA 1626trusted by the server for the connection to be authenticated. When using 1627certificates that are not chainable to a well-known CA, the certificate's CA 1628must be explicitly specified as a trusted or the connection will fail to 1629authenticate. 1630If the peer uses a certificate that doesn't match or chain to one of the 1631default CAs, use the <code>ca</code> option to provide a CA certificate that the peer's 1632certificate can match or chain to. 1633For self-signed certificates, the certificate is its own CA, and must be 1634provided. 1635For PEM encoded certificates, supported types are "TRUSTED CERTIFICATE", 1636"X509 CERTIFICATE", and "CERTIFICATE". 1637See also <a href="#tls_tls_rootcertificates"><code>tls.rootCertificates</code></a>.</li> 1638<li><code>cert</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#String_type" class="type"><string[]></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer[]></a> Cert chains in PEM format. One cert 1639chain should be provided per private key. Each cert chain should consist of 1640the PEM formatted certificate for a provided private <code>key</code>, followed by the 1641PEM formatted intermediate certificates (if any), in order, and not 1642including the root CA (the root CA must be pre-known to the peer, see <code>ca</code>). 1643When providing multiple cert chains, they do not have to be in the same 1644order as their private keys in <code>key</code>. If the intermediate certificates are 1645not provided, the peer will not be able to validate the certificate, and the 1646handshake will fail.</li> 1647<li><code>sigalgs</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Colon-separated list of supported signature algorithms. 1648The list can contain digest algorithms (<code>SHA256</code>, <code>MD5</code> etc.), public key 1649algorithms (<code>RSA-PSS</code>, <code>ECDSA</code> etc.), combination of both (e.g 1650'RSA+SHA384') or TLS v1.3 scheme names (e.g. <code>rsa_pss_pss_sha512</code>). 1651See <a href="https://www.openssl.org/docs/man1.1.1/man3/SSL_CTX_set1_sigalgs_list.html">OpenSSL man pages</a> 1652for more info.</li> 1653<li><code>ciphers</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Cipher suite specification, replacing the default. For 1654more information, see <a href="#tls_modifying_the_default_tls_cipher_suite">modifying the default cipher suite</a>. Permitted 1655ciphers can be obtained via <a href="#tls_tls_getciphers"><code>tls.getCiphers()</code></a>. Cipher names must be 1656uppercased in order for OpenSSL to accept them.</li> 1657<li><code>clientCertEngine</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Name of an OpenSSL engine which can provide the 1658client certificate.</li> 1659<li><code>crl</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#String_type" class="type"><string[]></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer[]></a> PEM formatted CRLs (Certificate 1660Revocation Lists).</li> 1661<li><code>dhparam</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> Diffie-Hellman parameters, required for 1662<a href="#tls_perfect_forward_secrecy">perfect forward secrecy</a>. Use <code>openssl dhparam</code> to create the parameters. 1663The key length must be greater than or equal to 1024 bits or else an error 1664will be thrown. Although 1024 bits is permissible, use 2048 bits or larger 1665for stronger security. If omitted or invalid, the parameters are silently 1666discarded and DHE ciphers will not be available.</li> 1667<li><code>ecdhCurve</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> A string describing a named curve or a colon separated 1668list of curve NIDs or names, for example <code>P-521:P-384:P-256</code>, to use for 1669ECDH key agreement. Set to <code>auto</code> to select the 1670curve automatically. Use <a href="crypto.html#crypto_crypto_getcurves"><code>crypto.getCurves()</code></a> to obtain a list of 1671available curve names. On recent releases, <code>openssl ecparam -list_curves</code> 1672will also display the name and description of each available elliptic curve. 1673<strong>Default:</strong> <a href="#tls_tls_default_ecdh_curve"><code>tls.DEFAULT_ECDH_CURVE</code></a>.</li> 1674<li><code>honorCipherOrder</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Attempt to use the server's cipher suite 1675preferences instead of the client's. When <code>true</code>, causes 1676<code>SSL_OP_CIPHER_SERVER_PREFERENCE</code> to be set in <code>secureOptions</code>, see 1677<a href="crypto.html#crypto_openssl_options">OpenSSL Options</a> for more information.</li> 1678<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="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="buffer.html#buffer_class_buffer" class="type"><Buffer[]></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object[]></a> Private keys in PEM format. 1679PEM allows the option of private keys being encrypted. Encrypted keys will 1680be decrypted with <code>options.passphrase</code>. Multiple keys using different 1681algorithms can be provided either as an array of unencrypted key strings or 1682buffers, or an array of objects in the form 1683<code>{pem: <string|buffer>[, passphrase: <string>]}</code>. The object form can only 1684occur in an array. <code>object.passphrase</code> is optional. Encrypted keys will be 1685decrypted with <code>object.passphrase</code> if provided, or <code>options.passphrase</code> if 1686it is not.</li> 1687<li><code>privateKeyEngine</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Name of an OpenSSL engine to get private key 1688from. Should be used together with <code>privateKeyIdentifier</code>.</li> 1689<li><code>privateKeyIdentifier</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Identifier of a private key managed by 1690an OpenSSL engine. Should be used together with <code>privateKeyEngine</code>. 1691Should not be set together with <code>key</code>, because both options define a 1692private key in different ways.</li> 1693<li><code>maxVersion</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Optionally set the maximum TLS version to allow. One 1694of <code>'TLSv1.3'</code>, <code>'TLSv1.2'</code>, <code>'TLSv1.1'</code>, or <code>'TLSv1'</code>. Cannot be specified 1695along with the <code>secureProtocol</code> option; use one or the other. 1696<strong>Default:</strong> <a href="#tls_tls_default_max_version"><code>tls.DEFAULT_MAX_VERSION</code></a>.</li> 1697<li><code>minVersion</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Optionally set the minimum TLS version to allow. One 1698of <code>'TLSv1.3'</code>, <code>'TLSv1.2'</code>, <code>'TLSv1.1'</code>, or <code>'TLSv1'</code>. Cannot be specified 1699along with the <code>secureProtocol</code> option; use one or the other. Avoid 1700setting to less than TLSv1.2, but it may be required for 1701interoperability. 1702<strong>Default:</strong> <a href="#tls_tls_default_min_version"><code>tls.DEFAULT_MIN_VERSION</code></a>.</li> 1703<li><code>passphrase</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Shared passphrase used for a single private key and/or 1704a PFX.</li> 1705<li><code>pfx</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#String_type" class="type"><string[]></a> | <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></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/Object" class="type"><Object[]></a> PFX or PKCS12 encoded 1706private key and certificate chain. <code>pfx</code> is an alternative to providing 1707<code>key</code> and <code>cert</code> individually. PFX is usually encrypted, if it is, 1708<code>passphrase</code> will be used to decrypt it. Multiple PFX can be provided either 1709as an array of unencrypted PFX buffers, or an array of objects in the form 1710<code>{buf: <string|buffer>[, passphrase: <string>]}</code>. The object form can only 1711occur in an array. <code>object.passphrase</code> is optional. Encrypted PFX will be 1712decrypted with <code>object.passphrase</code> if provided, or <code>options.passphrase</code> if 1713it is not.</li> 1714<li><code>secureOptions</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Optionally affect the OpenSSL protocol behavior, 1715which is not usually necessary. This should be used carefully if at all! 1716Value is a numeric bitmask of the <code>SSL_OP_*</code> options from 1717<a href="crypto.html#crypto_openssl_options">OpenSSL Options</a>.</li> 1718<li><code>secureProtocol</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Legacy mechanism to select the TLS protocol 1719version to use, it does not support independent control of the minimum and 1720maximum version, and does not support limiting the protocol to TLSv1.3. Use 1721<code>minVersion</code> and <code>maxVersion</code> instead. The possible values are listed as 1722<a href="https://www.openssl.org/docs/man1.1.1/man7/ssl.html#Dealing-with-Protocol-Methods">SSL_METHODS</a>, use the function names as strings. For example, use 1723<code>'TLSv1_1_method'</code> to force TLS version 1.1, or <code>'TLS_method'</code> to allow any 1724TLS protocol version up to TLSv1.3. It is not recommended to use TLS 1725versions less than 1.2, but it may be required for interoperability. 1726<strong>Default:</strong> none, see <code>minVersion</code>.</li> 1727<li><code>sessionIdContext</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Opaque identifier used by servers to ensure 1728session state is not shared between applications. Unused by clients.</li> 1729<li><code>ticketKeys</code>: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> 48-bytes of cryptographically strong pseudo-random 1730data. See <a href="#tls_session_resumption">Session Resumption</a> for more information.</li> 1731<li><code>sessionTimeout</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The number of seconds after which a TLS session 1732created by the server will no longer be resumable. See 1733<a href="#tls_session_resumption">Session Resumption</a> for more information. <strong>Default:</strong> <code>300</code>.</li> 1734</ul> 1735</li> 1736</ul> 1737<p><a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a> sets the default value of the <code>honorCipherOrder</code> option 1738to <code>true</code>, other APIs that create secure contexts leave it unset.</p> 1739<p><a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a> uses a 128 bit truncated SHA1 hash value generated 1740from <code>process.argv</code> as the default value of the <code>sessionIdContext</code> option, other 1741APIs that create secure contexts have no default value.</p> 1742<p>The <code>tls.createSecureContext()</code> method creates a <code>SecureContext</code> object. It is 1743usable as an argument to several <code>tls</code> APIs, such as <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a> 1744and <a href="#tls_server_addcontext_hostname_context"><code>server.addContext()</code></a>, but has no public methods.</p> 1745<p>A key is <em>required</em> for ciphers that use certificates. Either <code>key</code> or 1746<code>pfx</code> can be used to provide it.</p> 1747<p>If the <code>ca</code> option is not given, then Node.js will default to using 1748<a href="https://hg.mozilla.org/mozilla-central/raw-file/tip/security/nss/lib/ckfw/builtins/certdata.txt">Mozilla's publicly trusted list of CAs</a>.</p> 1749</section><section><h3><code>tls.createSecurePair([context][, isServer][, requestCert][, rejectUnauthorized][, options])</code><span><a class="mark" href="#tls_tls_createsecurepair_context_isserver_requestcert_rejectunauthorized_options" id="tls_tls_createsecurepair_context_isserver_requestcert_rejectunauthorized_options">#</a></span></h3> 1750<div class="api_metadata"> 1751<details class="changelog"><summary>History</summary> 1752<table> 1753<tbody><tr><th>Version</th><th>Changes</th></tr> 1754<tr><td>v5.0.0</td> 1755<td><p>ALPN options are supported now.</p></td></tr> 1756<tr><td>v0.11.3</td> 1757<td><p><span>Deprecated since: v0.11.3</span></p></td></tr> 1758<tr><td>v0.3.2</td> 1759<td><p><span>Added in: v0.3.2</span></p></td></tr> 1760</tbody></table> 1761</details> 1762</div> 1763<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated: Use <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a> instead.</div><p></p> 1764<ul> 1765<li><code>context</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> A secure context object as returned by 1766<code>tls.createSecureContext()</code></li> 1767<li><code>isServer</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> to specify that this TLS connection should be 1768opened as a server.</li> 1769<li><code>requestCert</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> to specify whether a server should request a 1770certificate from a connecting client. Only applies when <code>isServer</code> is <code>true</code>.</li> 1771<li><code>rejectUnauthorized</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If not <code>false</code> a server automatically reject 1772clients with invalid certificates. Only applies when <code>isServer</code> is <code>true</code>.</li> 1773<li><code>options</code> 1774<ul> 1775<li><code>enableTrace</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1776<li><code>secureContext</code>: A TLS context object from <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a></li> 1777<li><code>isServer</code>: If <code>true</code> the TLS socket will be instantiated in server-mode. 1778<strong>Default:</strong> <code>false</code>.</li> 1779<li><code>server</code> <a href="net.html#net_class_net_server" class="type"><net.Server></a> A <a href="net.html#net_class_net_server"><code>net.Server</code></a> instance</li> 1780<li><code>requestCert</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1781<li><code>rejectUnauthorized</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1782<li><code>ALPNProtocols</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1783<li><code>SNICallback</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1784<li><code>session</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A <code>Buffer</code> instance containing a TLS session.</li> 1785<li><code>requestOCSP</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If <code>true</code>, specifies that the OCSP status request 1786extension will be added to the client hello and an <code>'OCSPResponse'</code> event 1787will be emitted on the socket before establishing a secure communication.</li> 1788</ul> 1789</li> 1790</ul> 1791<p>Creates a new secure pair object with two streams, one of which reads and writes 1792the encrypted data and the other of which reads and writes the cleartext data. 1793Generally, the encrypted stream is piped to/from an incoming encrypted data 1794stream and the cleartext one is used as a replacement for the initial encrypted 1795stream.</p> 1796<p><code>tls.createSecurePair()</code> returns a <code>tls.SecurePair</code> object with <code>cleartext</code> and 1797<code>encrypted</code> stream properties.</p> 1798<p>Using <code>cleartext</code> has the same API as <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a>.</p> 1799<p>The <code>tls.createSecurePair()</code> method is now deprecated in favor of 1800<code>tls.TLSSocket()</code>. For example, the code:</p> 1801<pre><code class="language-js">pair = tls.<span class="hljs-title function_">createSecurePair</span>(<span class="hljs-comment">/* ... */</span>); 1802pair.<span class="hljs-property">encrypted</span>.<span class="hljs-title function_">pipe</span>(socket); 1803socket.<span class="hljs-title function_">pipe</span>(pair.<span class="hljs-property">encrypted</span>);</code></pre> 1804<p>can be replaced by:</p> 1805<pre><code class="language-js">secureSocket = tls.<span class="hljs-title function_">TLSSocket</span>(socket, options);</code></pre> 1806<p>where <code>secureSocket</code> has the same API as <code>pair.cleartext</code>.</p> 1807</section><section><h3><code>tls.createServer([options][, secureConnectionListener])</code><span><a class="mark" href="#tls_tls_createserver_options_secureconnectionlistener" id="tls_tls_createserver_options_secureconnectionlistener">#</a></span></h3> 1808<div class="api_metadata"> 1809<details class="changelog"><summary>History</summary> 1810<table> 1811<tbody><tr><th>Version</th><th>Changes</th></tr> 1812<tr><td>v12.3.0</td> 1813<td><p>The <code>options</code> parameter now supports <code>net.createServer()</code> options.</p></td></tr> 1814<tr><td>v9.3.0</td> 1815<td><p>The <code>options</code> parameter can now include <code>clientCertEngine</code>.</p></td></tr> 1816<tr><td>v8.0.0</td> 1817<td><p>The <code>ALPNProtocols</code> option can be a <code>TypedArray</code> or <code>DataView</code> now.</p></td></tr> 1818<tr><td>v5.0.0</td> 1819<td><p>ALPN options are supported now.</p></td></tr> 1820<tr><td>v0.3.2</td> 1821<td><p><span>Added in: v0.3.2</span></p></td></tr> 1822</tbody></table> 1823</details> 1824</div> 1825<ul> 1826<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1827<ul> 1828<li><code>ALPNProtocols</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="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> 1829An array of strings, <code>Buffer</code>s or <code>TypedArray</code>s or <code>DataView</code>s, or a single 1830<code>Buffer</code> or <code>TypedArray</code> or <code>DataView</code> containing the supported ALPN 1831protocols. <code>Buffer</code>s should have the format <code>[len][name][len][name]...</code> 1832e.g. <code>0x05hello0x05world</code>, where the first byte is the length of the next 1833protocol name. Passing an array is usually much simpler, e.g. 1834<code>['hello', 'world']</code>. (Protocols should be ordered by their priority.)</li> 1835<li><code>clientCertEngine</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Name of an OpenSSL engine which can provide the 1836client certificate.</li> 1837<li><code>enableTrace</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If <code>true</code>, <a href="#tls_tlssocket_enabletrace"><code>tls.TLSSocket.enableTrace()</code></a> will be 1838called on new connections. Tracing can be enabled after the secure 1839connection is established, but this option must be used to trace the secure 1840connection setup. <strong>Default:</strong> <code>false</code>.</li> 1841<li><code>handshakeTimeout</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> Abort the connection if the SSL/TLS handshake 1842does not finish in the specified number of milliseconds. 1843A <code>'tlsClientError'</code> is emitted on the <code>tls.Server</code> object whenever 1844a handshake times out. <strong>Default:</strong> <code>120000</code> (120 seconds).</li> 1845<li><code>rejectUnauthorized</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If not <code>false</code> the server will reject any 1846connection which is not authorized with the list of supplied CAs. This 1847option only has an effect if <code>requestCert</code> is <code>true</code>. <strong>Default:</strong> <code>true</code>.</li> 1848<li><code>requestCert</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If <code>true</code> the server will request a certificate from 1849clients that connect and attempt to verify that certificate. <strong>Default:</strong> 1850<code>false</code>.</li> 1851<li><code>sessionTimeout</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a> The number of seconds after which a TLS session 1852created by the server will no longer be resumable. See 1853<a href="#tls_session_resumption">Session Resumption</a> for more information. <strong>Default:</strong> <code>300</code>.</li> 1854<li><code>SNICallback(servername, callback)</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> A function that will be 1855called if the client supports SNI TLS extension. Two arguments will be 1856passed when called: <code>servername</code> and <code>callback</code>. <code>callback</code> is an 1857error-first callback that takes two optional arguments: <code>error</code> and <code>ctx</code>. 1858<code>ctx</code>, if provided, is a <code>SecureContext</code> instance. 1859<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> can be used to get a proper <code>SecureContext</code>. 1860If <code>callback</code> is called with a falsy <code>ctx</code> argument, the default secure 1861context of the server will be used. If <code>SNICallback</code> wasn't provided the 1862default callback with high-level API will be used (see below).</li> 1863<li><code>ticketKeys</code>: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> 48-bytes of cryptographically strong pseudo-random 1864data. See <a href="#tls_session_resumption">Session Resumption</a> for more information.</li> 1865<li><code>pskCallback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 1866<ul> 1867<li>socket: <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a> the server <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a> instance for 1868this connection.</li> 1869<li>identity: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> identity parameter sent from the client.</li> 1870<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> pre-shared key that must either be 1871a buffer or <code>null</code> to stop the negotiation process. Returned PSK must be 1872compatible with the selected cipher's digest.</li> 1873</ul> 1874When negotiating TLS-PSK (pre-shared keys), this function is called 1875with the identity provided by the client. 1876If the return value is <code>null</code> the negotiation process will stop and an 1877"unknown_psk_identity" alert message will be sent to the other party. 1878If the server wishes to hide the fact that the PSK identity was not known, 1879the callback must provide some random data as <code>psk</code> to make the connection 1880fail with "decrypt_error" before negotiation is finished. 1881PSK ciphers are disabled by default, and using TLS-PSK thus 1882requires explicitly specifying a cipher suite with the <code>ciphers</code> option. 1883More information can be found in the <a href="https://tools.ietf.org/html/rfc4279">RFC 4279</a>.</li> 1884<li><code>pskIdentityHint</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> optional hint to send to a client to help 1885with selecting the identity during TLS-PSK negotiation. Will be ignored 1886in TLS 1.3. Upon failing to set pskIdentityHint <code>'tlsClientError'</code> will be 1887emitted with <code>'ERR_TLS_PSK_SET_IDENTIY_HINT_FAILED'</code> code.</li> 1888<li>...: Any <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> option can be provided. For 1889servers, the identity options (<code>pfx</code>, <code>key</code>/<code>cert</code> or <code>pskCallback</code>) 1890are usually required.</li> 1891<li>...: Any <a href="net.html#net_net_createserver_options_connectionlistener"><code>net.createServer()</code></a> option can be provided.</li> 1892</ul> 1893</li> 1894<li><code>secureConnectionListener</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1895<li>Returns: <a href="tls.html#tls_class_tls_server" class="type"><tls.Server></a></li> 1896</ul> 1897<p>Creates a new <a href="#tls_class_tls_server"><code>tls.Server</code></a>. The <code>secureConnectionListener</code>, if provided, is 1898automatically set as a listener for the <a href="#tls_event_secureconnection"><code>'secureConnection'</code></a> event.</p> 1899<p>The <code>ticketKeys</code> options is automatically shared between <code>cluster</code> module 1900workers.</p> 1901<p>The following illustrates a simple echo server:</p> 1902<pre><code class="language-js"><span class="hljs-keyword">const</span> tls = <span class="hljs-built_in">require</span>(<span class="hljs-string">'tls'</span>); 1903<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 1904 1905<span class="hljs-keyword">const</span> options = { 1906 <span class="hljs-attr">key</span>: fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'server-key.pem'</span>), 1907 <span class="hljs-attr">cert</span>: fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'server-cert.pem'</span>), 1908 1909 <span class="hljs-comment">// This is necessary only if using client certificate authentication.</span> 1910 <span class="hljs-attr">requestCert</span>: <span class="hljs-literal">true</span>, 1911 1912 <span class="hljs-comment">// This is necessary only if the client uses a self-signed certificate.</span> 1913 <span class="hljs-attr">ca</span>: [ fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'client-cert.pem'</span>) ] 1914}; 1915 1916<span class="hljs-keyword">const</span> server = tls.<span class="hljs-title function_">createServer</span>(options, <span class="hljs-function">(<span class="hljs-params">socket</span>) =></span> { 1917 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'server connected'</span>, 1918 socket.<span class="hljs-property">authorized</span> ? <span class="hljs-string">'authorized'</span> : <span class="hljs-string">'unauthorized'</span>); 1919 socket.<span class="hljs-title function_">write</span>(<span class="hljs-string">'welcome!\n'</span>); 1920 socket.<span class="hljs-title function_">setEncoding</span>(<span class="hljs-string">'utf8'</span>); 1921 socket.<span class="hljs-title function_">pipe</span>(socket); 1922}); 1923server.<span class="hljs-title function_">listen</span>(<span class="hljs-number">8000</span>, <span class="hljs-function">() =></span> { 1924 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'server bound'</span>); 1925});</code></pre> 1926<p>The server can be tested by connecting to it using the example client from 1927<a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a>.</p> 1928</section><section><h3><code>tls.getCiphers()</code><span><a class="mark" href="#tls_tls_getciphers" id="tls_tls_getciphers">#</a></span></h3> 1929<div class="api_metadata"> 1930<span>Added in: v0.10.2</span> 1931</div> 1932<ul> 1933<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 1934</ul> 1935<p>Returns an array with the names of the supported TLS ciphers. The names are 1936lower-case for historical reasons, but must be uppercased to be used in 1937the <code>ciphers</code> option of <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>.</p> 1938<p>Cipher names that start with <code>'tls_'</code> are for TLSv1.3, all the others are for 1939TLSv1.2 and below.</p> 1940<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(tls.<span class="hljs-title function_">getCiphers</span>()); <span class="hljs-comment">// ['aes128-gcm-sha256', 'aes128-sha', ...]</span></code></pre> 1941</section><section><h3><code>tls.rootCertificates</code><span><a class="mark" href="#tls_tls_rootcertificates" id="tls_tls_rootcertificates">#</a></span></h3> 1942<div class="api_metadata"> 1943<span>Added in: v12.3.0</span> 1944</div> 1945<ul> 1946<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 1947</ul> 1948<p>An immutable array of strings representing the root certificates (in PEM format) 1949from the bundled Mozilla CA store as supplied by current Node.js version.</p> 1950<p>The bundled CA store, as supplied by Node.js, is a snapshot of Mozilla CA store 1951that is fixed at release time. It is identical on all supported platforms.</p> 1952</section><section><h3><code>tls.DEFAULT_ECDH_CURVE</code><span><a class="mark" href="#tls_tls_default_ecdh_curve" id="tls_tls_default_ecdh_curve">#</a></span></h3> 1953<div class="api_metadata"> 1954<details class="changelog"><summary>History</summary> 1955<table> 1956<tbody><tr><th>Version</th><th>Changes</th></tr> 1957<tr><td>v10.0.0</td> 1958<td><p>Default value changed to <code>'auto'</code>.</p></td></tr> 1959<tr><td>v0.11.13</td> 1960<td><p><span>Added in: v0.11.13</span></p></td></tr> 1961</tbody></table> 1962</details> 1963</div> 1964<p>The default curve name to use for ECDH key agreement in a tls server. The 1965default value is <code>'auto'</code>. See <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> for further 1966information.</p> 1967</section><section><h3><code>tls.DEFAULT_MAX_VERSION</code><span><a class="mark" href="#tls_tls_default_max_version" id="tls_tls_default_max_version">#</a></span></h3> 1968<div class="api_metadata"> 1969<span>Added in: v11.4.0</span> 1970</div> 1971<ul> 1972<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The default value of the <code>maxVersion</code> option of 1973<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. It can be assigned any of the supported TLS 1974protocol versions, <code>'TLSv1.3'</code>, <code>'TLSv1.2'</code>, <code>'TLSv1.1'</code>, or <code>'TLSv1'</code>. 1975<strong>Default:</strong> <code>'TLSv1.3'</code>, unless changed using CLI options. Using 1976<code>--tls-max-v1.2</code> sets the default to <code>'TLSv1.2'</code>. Using <code>--tls-max-v1.3</code> sets 1977the default to <code>'TLSv1.3'</code>. If multiple of the options are provided, the 1978highest maximum is used.</li> 1979</ul> 1980</section><section><h3><code>tls.DEFAULT_MIN_VERSION</code><span><a class="mark" href="#tls_tls_default_min_version" id="tls_tls_default_min_version">#</a></span></h3> 1981<div class="api_metadata"> 1982<span>Added in: v11.4.0</span> 1983</div> 1984<ul> 1985<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The default value of the <code>minVersion</code> option of 1986<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. It can be assigned any of the supported TLS 1987protocol versions, <code>'TLSv1.3'</code>, <code>'TLSv1.2'</code>, <code>'TLSv1.1'</code>, or <code>'TLSv1'</code>. 1988<strong>Default:</strong> <code>'TLSv1.2'</code>, unless changed using CLI options. Using 1989<code>--tls-min-v1.0</code> sets the default to <code>'TLSv1'</code>. Using <code>--tls-min-v1.1</code> sets 1990the default to <code>'TLSv1.1'</code>. Using <code>--tls-min-v1.3</code> sets the default to 1991<code>'TLSv1.3'</code>. If multiple of the options are provided, the lowest minimum is 1992used.</li> 1993</ul></section> 1994 <!-- API END --> 1995 </div> 1996 </div> 1997 </div> 1998 <script> 1999 'use strict'; 2000 { 2001 const kCustomPreference = 'customDarkTheme'; 2002 const userSettings = sessionStorage.getItem(kCustomPreference); 2003 const themeToggleButton = document.getElementById('theme-toggle-btn'); 2004 if (userSettings === null && window.matchMedia) { 2005 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 2006 if ('onchange' in mq) { 2007 function mqChangeListener(e) { 2008 document.body.classList.toggle('dark-mode', e.matches); 2009 } 2010 mq.addEventListener('change', mqChangeListener); 2011 if (themeToggleButton) { 2012 themeToggleButton.addEventListener('click', function() { 2013 mq.removeEventListener('change', mqChangeListener); 2014 }, { once: true }); 2015 } 2016 } 2017 if (mq.matches) { 2018 document.body.classList.add('dark-mode'); 2019 } 2020 } else if (userSettings === 'true') { 2021 document.body.classList.add('dark-mode'); 2022 } 2023 if (themeToggleButton) { 2024 themeToggleButton.hidden = false; 2025 themeToggleButton.addEventListener('click', function() { 2026 sessionStorage.setItem( 2027 kCustomPreference, 2028 document.body.classList.toggle('dark-mode') 2029 ); 2030 }); 2031 } 2032 } 2033 </script> 2034</body> 2035</html> 2036