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<header> 91 <div class="header-container"> 92 <h1>Node.js v14.20.1 documentation</h1> 93 <button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden> 94 <svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24"> 95 <path fill="none" d="M0 0h24v24H0z" /> 96 <path d="M11.1 12.08c-2.33-4.51-.5-8.48.53-10.07C6.27 2.2 1.98 6.59 1.98 12c0 .14.02.28.02.42.62-.27 1.29-.42 2-.42 1.66 0 3.18.83 4.1 2.15A4.01 4.01 0 0111 18c0 1.52-.87 2.83-2.12 3.51.98.32 2.03.5 3.11.5 3.5 0 6.58-1.8 8.37-4.52-2.36.23-6.98-.97-9.26-5.41z"/> 97 <path d="M7 16h-.18C6.4 14.84 5.3 14 4 14c-1.66 0-3 1.34-3 3s1.34 3 3 3h3c1.1 0 2-.9 2-2s-.9-2-2-2z"/> 98 </svg> 99 <svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24"> 100 <path d="M0 0h24v24H0z" fill="none" /> 101 <path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 10.5H1v2h3v-2zm9-9.95h-2V3.5h2V.55zm7.45 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href="#tls_session_tickets">Session tickets</a></li> 157</ul> 158</li> 159</ul> 160</li> 161<li><a href="#tls_modifying_the_default_tls_cipher_suite">Modifying the default TLS cipher suite</a></li> 162<li><span class="stability_0"><a href="#tls_class_tls_cryptostream">Class: <code>tls.CryptoStream</code></a></span> 163<ul> 164<li><a href="#tls_cryptostream_byteswritten"><code>cryptoStream.bytesWritten</code></a></li> 165</ul> 166</li> 167<li><span class="stability_0"><a href="#tls_class_tls_securepair">Class: <code>tls.SecurePair</code></a></span> 168<ul> 169<li><a href="#tls_event_secure">Event: <code>'secure'</code></a></li> 170</ul> 171</li> 172<li><a href="#tls_class_tls_server">Class: <code>tls.Server</code></a> 173<ul> 174<li><a href="#tls_event_connection">Event: <code>'connection'</code></a></li> 175<li><a href="#tls_event_keylog">Event: <code>'keylog'</code></a></li> 176<li><a href="#tls_event_newsession">Event: <code>'newSession'</code></a></li> 177<li><a href="#tls_event_ocsprequest">Event: <code>'OCSPRequest'</code></a></li> 178<li><a href="#tls_event_resumesession">Event: <code>'resumeSession'</code></a></li> 179<li><a href="#tls_event_secureconnection">Event: <code>'secureConnection'</code></a></li> 180<li><a href="#tls_event_tlsclienterror">Event: <code>'tlsClientError'</code></a></li> 181<li><a href="#tls_server_addcontext_hostname_context"><code>server.addContext(hostname, context)</code></a></li> 182<li><a href="#tls_server_address"><code>server.address()</code></a></li> 183<li><a href="#tls_server_close_callback"><code>server.close([callback])</code></a></li> 184<li><span class="stability_0"><a href="#tls_server_connections"><code>server.connections</code></a></span></li> 185<li><a href="#tls_server_getticketkeys"><code>server.getTicketKeys()</code></a></li> 186<li><a href="#tls_server_listen"><code>server.listen()</code></a></li> 187<li><a href="#tls_server_setsecurecontext_options"><code>server.setSecureContext(options)</code></a></li> 188<li><a href="#tls_server_setticketkeys_keys"><code>server.setTicketKeys(keys)</code></a></li> 189</ul> 190</li> 191<li><a href="#tls_class_tls_tlssocket">Class: <code>tls.TLSSocket</code></a> 192<ul> 193<li><a href="#tls_new_tls_tlssocket_socket_options"><code>new tls.TLSSocket(socket[, options])</code></a></li> 194<li><a href="#tls_event_keylog_1">Event: <code>'keylog'</code></a></li> 195<li><a href="#tls_event_ocspresponse">Event: <code>'OCSPResponse'</code></a></li> 196<li><a href="#tls_event_secureconnect">Event: <code>'secureConnect'</code></a></li> 197<li><a href="#tls_event_session">Event: <code>'session'</code></a></li> 198<li><a href="#tls_tlssocket_address"><code>tlsSocket.address()</code></a></li> 199<li><a href="#tls_tlssocket_authorizationerror"><code>tlsSocket.authorizationError</code></a></li> 200<li><a href="#tls_tlssocket_authorized"><code>tlsSocket.authorized</code></a></li> 201<li><a href="#tls_tlssocket_disablerenegotiation"><code>tlsSocket.disableRenegotiation()</code></a></li> 202<li><a href="#tls_tlssocket_enabletrace"><code>tlsSocket.enableTrace()</code></a></li> 203<li><a href="#tls_tlssocket_encrypted"><code>tlsSocket.encrypted</code></a></li> 204<li><a href="#tls_tlssocket_getcertificate"><code>tlsSocket.getCertificate()</code></a></li> 205<li><a href="#tls_tlssocket_getcipher"><code>tlsSocket.getCipher()</code></a></li> 206<li><a href="#tls_tlssocket_getephemeralkeyinfo"><code>tlsSocket.getEphemeralKeyInfo()</code></a></li> 207<li><a href="#tls_tlssocket_getfinished"><code>tlsSocket.getFinished()</code></a></li> 208<li><a href="#tls_tlssocket_getpeercertificate_detailed"><code>tlsSocket.getPeerCertificate([detailed])</code></a> 209<ul> 210<li><a href="#tls_certificate_object">Certificate object</a></li> 211</ul> 212</li> 213<li><a href="#tls_tlssocket_getpeerfinished"><code>tlsSocket.getPeerFinished()</code></a></li> 214<li><a href="#tls_tlssocket_getprotocol"><code>tlsSocket.getProtocol()</code></a></li> 215<li><a href="#tls_tlssocket_getsession"><code>tlsSocket.getSession()</code></a></li> 216<li><a href="#tls_tlssocket_getsharedsigalgs"><code>tlsSocket.getSharedSigalgs()</code></a></li> 217<li><a href="#tls_tlssocket_exportkeyingmaterial_length_label_context"><code>tlsSocket.exportKeyingMaterial(length, label[, context])</code></a></li> 218<li><a href="#tls_tlssocket_gettlsticket"><code>tlsSocket.getTLSTicket()</code></a></li> 219<li><a href="#tls_tlssocket_issessionreused"><code>tlsSocket.isSessionReused()</code></a></li> 220<li><a href="#tls_tlssocket_localaddress"><code>tlsSocket.localAddress</code></a></li> 221<li><a href="#tls_tlssocket_localport"><code>tlsSocket.localPort</code></a></li> 222<li><a href="#tls_tlssocket_remoteaddress"><code>tlsSocket.remoteAddress</code></a></li> 223<li><a href="#tls_tlssocket_remotefamily"><code>tlsSocket.remoteFamily</code></a></li> 224<li><a href="#tls_tlssocket_remoteport"><code>tlsSocket.remotePort</code></a></li> 225<li><a href="#tls_tlssocket_renegotiate_options_callback"><code>tlsSocket.renegotiate(options, callback)</code></a></li> 226<li><a href="#tls_tlssocket_setmaxsendfragment_size"><code>tlsSocket.setMaxSendFragment(size)</code></a></li> 227</ul> 228</li> 229<li><a href="#tls_tls_checkserveridentity_hostname_cert"><code>tls.checkServerIdentity(hostname, cert)</code></a></li> 230<li><a href="#tls_tls_connect_options_callback"><code>tls.connect(options[, callback])</code></a></li> 231<li><a href="#tls_tls_connect_path_options_callback"><code>tls.connect(path[, options][, callback])</code></a></li> 232<li><a href="#tls_tls_connect_port_host_options_callback"><code>tls.connect(port[, host][, options][, callback])</code></a></li> 233<li><a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext([options])</code></a></li> 234<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> 235<li><a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer([options][, secureConnectionListener])</code></a></li> 236<li><a href="#tls_tls_getciphers"><code>tls.getCiphers()</code></a></li> 237<li><a href="#tls_tls_rootcertificates"><code>tls.rootCertificates</code></a></li> 238<li><a href="#tls_tls_default_ecdh_curve"><code>tls.DEFAULT_ECDH_CURVE</code></a></li> 239<li><a href="#tls_tls_default_max_version"><code>tls.DEFAULT_MAX_VERSION</code></a></li> 240<li><a href="#tls_tls_default_min_version"><code>tls.DEFAULT_MIN_VERSION</code></a></li> 241</ul> 242</li> 243</ul></details> 244 245 <div id="apicontent"> 246 <h2>TLS (SSL)<span><a class="mark" href="#tls_tls_ssl" id="tls_tls_ssl">#</a></span></h2> 247 248<p></p><div class="api_stability api_stability_2"><a href="documentation.html#documentation_stability_index">Stability: 2</a> - Stable</div><p></p> 249<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v14.20.1/lib/tls.js">lib/tls.js</a></p> 250<p>The <code>tls</code> module provides an implementation of the Transport Layer Security 251(TLS) and Secure Socket Layer (SSL) protocols that is built on top of OpenSSL. 252The module can be accessed using:</p> 253<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> 254<section><h3>TLS/SSL concepts<span><a class="mark" href="#tls_tls_ssl_concepts" id="tls_tls_ssl_concepts">#</a></span></h3> 255<p>The TLS/SSL is a public/private key infrastructure (PKI). For most common 256cases, each client and server must have a <em>private key</em>.</p> 257<p>Private keys can be generated in multiple ways. The example below illustrates 258use of the OpenSSL command-line interface to generate a 2048-bit RSA private 259key:</p> 260<pre><code class="language-bash">openssl genrsa -out ryans-key.pem 2048</code></pre> 261<p>With TLS/SSL, all servers (and some clients) must have a <em>certificate</em>. 262Certificates are <em>public keys</em> that correspond to a private key, and that are 263digitally signed either by a Certificate Authority or by the owner of the 264private key (such certificates are referred to as "self-signed"). The first 265step to obtaining a certificate is to create a <em>Certificate Signing Request</em> 266(CSR) file.</p> 267<p>The OpenSSL command-line interface can be used to generate a CSR for a private 268key:</p> 269<pre><code class="language-bash">openssl req -new -sha256 -key ryans-key.pem -out ryans-csr.pem</code></pre> 270<p>Once the CSR file is generated, it can either be sent to a Certificate 271Authority for signing or used to generate a self-signed certificate.</p> 272<p>Creating a self-signed certificate using the OpenSSL command-line interface 273is illustrated in the example below:</p> 274<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> 275<p>Once the certificate is generated, it can be used to generate a <code>.pfx</code> or 276<code>.p12</code> file:</p> 277<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 \ 278 -certfile ca-cert.pem -out ryans.pfx</code></pre> 279<p>Where:</p> 280<ul> 281<li><code>in</code>: is the signed certificate</li> 282<li><code>inkey</code>: is the associated private key</li> 283<li><code>certfile</code>: is a concatenation of all Certificate Authority (CA) certs into 284a single file, e.g. <code>cat ca1-cert.pem ca2-cert.pem > ca-cert.pem</code></li> 285</ul> 286<h4>Perfect forward secrecy<span><a class="mark" href="#tls_perfect_forward_secrecy" id="tls_perfect_forward_secrecy">#</a></span></h4> 287 288<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 289of key-agreement (i.e., key-exchange) methods. That is, the server and client 290keys are used to negotiate new temporary keys that are used specifically and 291only for the current communication session. Practically, this means that even 292if the server's private key is compromised, communication can only be decrypted 293by eavesdroppers if the attacker manages to obtain the key-pair specifically 294generated for the session.</p> 295<p>Perfect forward secrecy is achieved by randomly generating a key pair for 296key-agreement on every TLS/SSL handshake (in contrast to using the same key for 297all sessions). Methods implementing this technique are called "ephemeral".</p> 298<p>Currently two methods are commonly used to achieve perfect forward secrecy (note 299the character "E" appended to the traditional abbreviations):</p> 300<ul> 301<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> 302<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 303key-agreement protocol.</li> 304</ul> 305<p>Ephemeral methods may have some performance drawbacks, because key generation 306is expensive.</p> 307<p>To use perfect forward secrecy using <code>DHE</code> with the <code>tls</code> module, it is required 308to generate Diffie-Hellman parameters and specify them with the <code>dhparam</code> 309option to <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. The following illustrates the use of 310the OpenSSL command-line interface to generate such parameters:</p> 311<pre><code class="language-bash">openssl dhparam -outform PEM -out dhparam.pem 2048</code></pre> 312<p>If using perfect forward secrecy using <code>ECDHE</code>, Diffie-Hellman parameters are 313not required and a default ECDHE curve will be used. The <code>ecdhCurve</code> property 314can be used when creating a TLS Server to specify the list of names of supported 315curves to use, see <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a> for more info.</p> 316<p>Perfect forward secrecy was optional up to TLSv1.2, but it is not optional for 317TLSv1.3, because all TLSv1.3 cipher suites use ECDHE.</p> 318<h4>ALPN and SNI<span><a class="mark" href="#tls_alpn_and_sni" id="tls_alpn_and_sni">#</a></span></h4> 319 320<p>ALPN (Application-Layer Protocol Negotiation Extension) and 321SNI (Server Name Indication) are TLS handshake extensions:</p> 322<ul> 323<li>ALPN: Allows the use of one TLS server for multiple protocols (HTTP, HTTP/2)</li> 324<li>SNI: Allows the use of one TLS server for multiple hostnames with different 325SSL certificates.</li> 326</ul> 327<h4>Pre-shared keys<span><a class="mark" href="#tls_pre_shared_keys" id="tls_pre_shared_keys">#</a></span></h4> 328 329<p>TLS-PSK support is available as an alternative to normal certificate-based 330authentication. It uses a pre-shared key instead of certificates to 331authenticate a TLS connection, providing mutual authentication. 332TLS-PSK and public key infrastructure are not mutually exclusive. Clients and 333servers can accommodate both, choosing either of them during the normal cipher 334negotiation step.</p> 335<p>TLS-PSK is only a good choice where means exist to securely share a 336key with every connecting machine, so it does not replace PKI 337(Public Key Infrastructure) for the majority of TLS uses. 338The TLS-PSK implementation in OpenSSL has seen many security flaws in 339recent years, mostly because it is used only by a minority of applications. 340Please consider all alternative solutions before switching to PSK ciphers. 341Upon generating PSK it is of critical importance to use sufficient entropy as 342discussed in <a href="https://tools.ietf.org/html/rfc4086">RFC 4086</a>. Deriving a shared secret from a password or other 343low-entropy sources is not secure.</p> 344<p>PSK ciphers are disabled by default, and using TLS-PSK thus requires explicitly 345specifying a cipher suite with the <code>ciphers</code> option. The list of available 346ciphers can be retrieved via <code>openssl ciphers -v 'PSK'</code>. All TLS 1.3 347ciphers are eligible for PSK but currently only those that use SHA256 digest are 348supported they can be retrieved via <code>openssl ciphers -v -s -tls1_3 -psk</code>.</p> 349<p>According to the <a href="https://tools.ietf.org/html/rfc4279">RFC 4279</a>, PSK identities up to 128 bytes in length and 350PSKs up to 64 bytes in length must be supported. As of OpenSSL 1.1.0 351maximum identity size is 128 bytes, and maximum PSK length is 256 bytes.</p> 352<p>The current implementation doesn't support asynchronous PSK callbacks due to the 353limitations of the underlying OpenSSL API.</p> 354<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> 355 356<p>The TLS protocol allows clients to renegotiate certain aspects of the TLS 357session. Unfortunately, session renegotiation requires a disproportionate amount 358of server-side resources, making it a potential vector for denial-of-service 359attacks.</p> 360<p>To mitigate the risk, renegotiation is limited to three times every ten minutes. 361An <code>'error'</code> event is emitted on the <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a> instance when this 362threshold is exceeded. The limits are configurable:</p> 363<ul> 364<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 365requests. <strong>Default:</strong> <code>3</code>.</li> 366<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 367in seconds. <strong>Default:</strong> <code>600</code> (10 minutes).</li> 368</ul> 369<p>The default renegotiation limits should not be modified without a full 370understanding of the implications and risks.</p> 371<p>TLSv1.3 does not support renegotiation.</p> 372<h4>Session resumption<span><a class="mark" href="#tls_session_resumption" id="tls_session_resumption">#</a></span></h4> 373<p>Establishing a TLS session can be relatively slow. The process can be sped 374up by saving and later reusing the session state. There are several mechanisms 375to do so, discussed here from oldest to newest (and preferred).</p> 376<h5>Session identifiers<span><a class="mark" href="#tls_session_identifiers" id="tls_session_identifiers">#</a></span></h5> 377<p>Servers generate a unique ID for new connections and 378send it to the client. Clients and servers save the session state. When 379reconnecting, clients send the ID of their saved session state and if the server 380also has the state for that ID, it can agree to use it. Otherwise, the server 381will create a new session. See <a href="https://www.ietf.org/rfc/rfc2246.txt">RFC 2246</a> for more information, page 23 and 38230.</p> 383<p>Resumption using session identifiers is supported by most web browsers when 384making HTTPS requests.</p> 385<p>For Node.js, clients wait for the <a href="#tls_event_session"><code>'session'</code></a> event to get the session data, 386and provide the data to the <code>session</code> option of a subsequent <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> 387to reuse the session. Servers must 388implement handlers for the <a href="#tls_event_newsession"><code>'newSession'</code></a> and <a href="#tls_event_resumesession"><code>'resumeSession'</code></a> events 389to save and restore the session data using the session ID as the lookup key to 390reuse sessions. To reuse sessions across load balancers or cluster workers, 391servers must use a shared session cache (such as Redis) in their session 392handlers.</p> 393<h5>Session tickets<span><a class="mark" href="#tls_session_tickets" id="tls_session_tickets">#</a></span></h5> 394<p>The servers encrypt the entire session state and send it 395to the client as a "ticket". When reconnecting, the state is sent to the server 396in the initial connection. This mechanism avoids the need for server-side 397session cache. If the server doesn't use the ticket, for any reason (failure 398to decrypt it, it's too old, etc.), it will create a new session and send a new 399ticket. See <a href="https://tools.ietf.org/html/rfc5077">RFC 5077</a> for more information.</p> 400<p>Resumption using session tickets is becoming commonly supported by many web 401browsers when making HTTPS requests.</p> 402<p>For Node.js, clients use the same APIs for resumption with session identifiers 403as for resumption with session tickets. For debugging, if 404<a href="#tls_tlssocket_gettlsticket"><code>tls.TLSSocket.getTLSTicket()</code></a> returns a value, the session data contains a 405ticket, otherwise it contains client-side session state.</p> 406<p>With TLSv1.3, be aware that multiple tickets may be sent by the server, 407resulting in multiple <code>'session'</code> events, see <a href="#tls_event_session"><code>'session'</code></a> for more 408information.</p> 409<p>Single process servers need no specific implementation to use session tickets. 410To use session tickets across server restarts or load balancers, servers must 411all have the same ticket keys. There are three 16-byte keys internally, but the 412tls API exposes them as a single 48-byte buffer for convenience.</p> 413<p>Its possible to get the ticket keys by calling <a href="#tls_server_getticketkeys"><code>server.getTicketKeys()</code></a> on 414one server instance and then distribute them, but it is more reasonable to 415securely generate 48 bytes of secure random data and set them with the 416<code>ticketKeys</code> option of <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>. The keys should be regularly 417regenerated and server's keys can be reset with 418<a href="#tls_server_setticketkeys_keys"><code>server.setTicketKeys()</code></a>.</p> 419<p>Session ticket keys are cryptographic keys, and they <em><strong>must be stored 420securely</strong></em>. With TLS 1.2 and below, if they are compromised all sessions that 421used tickets encrypted with them can be decrypted. They should not be stored 422on disk, and they should be regenerated regularly.</p> 423<p>If clients advertise support for tickets, the server will send them. The 424server can disable tickets by supplying 425<code>require('constants').SSL_OP_NO_TICKET</code> in <code>secureOptions</code>.</p> 426<p>Both session identifiers and session tickets timeout, causing the server to 427create new sessions. The timeout can be configured with the <code>sessionTimeout</code> 428option of <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>.</p> 429<p>For all the mechanisms, when resumption fails, servers will create new sessions. 430Since failing to resume the session does not cause TLS/HTTPS connection 431failures, it is easy to not notice unnecessarily poor TLS performance. The 432OpenSSL CLI can be used to verify that servers are resuming sessions. Use the 433<code>-reconnect</code> option to <code>openssl s_client</code>, for example:</p> 434<pre><code class="language-console"><span class="hljs-meta">$ </span><span class="language-bash">openssl s_client -connect localhost:443 -reconnect</span></code></pre> 435<p>Read through the debug output. The first connection should say "New", for 436example:</p> 437<pre><code class="language-text">New, TLSv1.2, Cipher is ECDHE-RSA-AES128-GCM-SHA256</code></pre> 438<p>Subsequent connections should say "Reused", for example:</p> 439<pre><code class="language-text">Reused, TLSv1.2, Cipher is ECDHE-RSA-AES128-GCM-SHA256</code></pre> 440</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> 441<p>Node.js is built with a default suite of enabled and disabled TLS ciphers. This 442default cipher list can be configured when building Node.js to allow 443distributions to provide their own default list.</p> 444<p>The following command can be used to show the default cipher suite:</p> 445<pre><code class="language-console">node -p crypto.constants.defaultCoreCipherList | tr ':' '\n' 446TLS_AES_256_GCM_SHA384 447TLS_CHACHA20_POLY1305_SHA256 448TLS_AES_128_GCM_SHA256 449ECDHE-RSA-AES128-GCM-SHA256 450ECDHE-ECDSA-AES128-GCM-SHA256 451ECDHE-RSA-AES256-GCM-SHA384 452ECDHE-ECDSA-AES256-GCM-SHA384 453DHE-RSA-AES128-GCM-SHA256 454ECDHE-RSA-AES128-SHA256 455DHE-RSA-AES128-SHA256 456ECDHE-RSA-AES256-SHA384 457DHE-RSA-AES256-SHA384 458ECDHE-RSA-AES256-SHA256 459DHE-RSA-AES256-SHA256 460HIGH 461!aNULL 462!eNULL 463!EXPORT 464!DES 465!RC4 466!MD5 467!PSK 468!SRP 469!CAMELLIA</code></pre> 470<p>This default can be replaced entirely using the <a href="cli.html#cli_tls_cipher_list_list"><code>--tls-cipher-list</code></a> 471command-line switch (directly, or via the <a href="cli.html#cli_node_options_options"><code>NODE_OPTIONS</code></a> environment 472variable). For instance, the following makes <code>ECDHE-RSA-AES128-GCM-SHA256:!RC4</code> 473the default TLS cipher suite:</p> 474<pre><code class="language-bash">node --tls-cipher-list=<span class="hljs-string">'ECDHE-RSA-AES128-GCM-SHA256:!RC4'</span> server.js 475 476<span class="hljs-built_in">export</span> NODE_OPTIONS=--tls-cipher-list=<span class="hljs-string">'ECDHE-RSA-AES128-GCM-SHA256:!RC4'</span> 477node server.js</code></pre> 478<p>The default can also be replaced on a per client or server basis using the 479<code>ciphers</code> option from <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>, which is also available 480in <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 481<a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a>s.</p> 482<p>The ciphers list can contain a mixture of TLSv1.3 cipher suite names, the ones 483that start with <code>'TLS_'</code>, and specifications for TLSv1.2 and below cipher 484suites. The TLSv1.2 ciphers support a legacy specification format, consult 485the 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 486specifications do <em>not</em> apply to TLSv1.3 ciphers. The TLSv1.3 suites can only 487be enabled by including their full name in the cipher list. They cannot, for 488example, be enabled or disabled by using the legacy TLSv1.2 <code>'EECDH'</code> or 489<code>'!EECDH'</code> specification.</p> 490<p>Despite the relative order of TLSv1.3 and TLSv1.2 cipher suites, the TLSv1.3 491protocol is significantly more secure than TLSv1.2, and will always be chosen 492over TLSv1.2 if the handshake indicates it is supported, and if any TLSv1.3 493cipher suites are enabled.</p> 494<p>The default cipher suite included within Node.js has been carefully 495selected to reflect current security best practices and risk mitigation. 496Changing the default cipher suite can have a significant impact on the security 497of an application. The <code>--tls-cipher-list</code> switch and <code>ciphers</code> option should by 498used only if absolutely necessary.</p> 499<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 500cryptography' setting</a> and also prefers ECDHE and DHE ciphers for perfect 501forward secrecy, while offering <em>some</em> backward compatibility.</p> 502<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 503attacks affecting larger AES key sizes</a>.</p> 504<p>Old clients that rely on insecure and deprecated RC4 or DES-based ciphers 505(like Internet Explorer 6) cannot complete the handshaking process with 506the default configuration. If these clients <em>must</em> be supported, the 507<a href="https://wiki.mozilla.org/Security/Server_Side_TLS">TLS recommendations</a> may offer a compatible cipher suite. For more details 508on 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> 509<p>There are only 5 TLSv1.3 cipher suites:</p> 510<ul> 511<li><code>'TLS_AES_256_GCM_SHA384'</code></li> 512<li><code>'TLS_CHACHA20_POLY1305_SHA256'</code></li> 513<li><code>'TLS_AES_128_GCM_SHA256'</code></li> 514<li><code>'TLS_AES_128_CCM_SHA256'</code></li> 515<li><code>'TLS_AES_128_CCM_8_SHA256'</code></li> 516</ul> 517<p>The first 3 are enabled by default. The last 2 <code>CCM</code>-based suites are supported 518by TLSv1.3 because they may be more performant on constrained systems, but they 519are not enabled by default since they offer less security.</p> 520</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> 521<div class="api_metadata"> 522<span>Added in: v0.3.4</span><span>Deprecated since: v0.11.3</span> 523</div> 524<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> 525<p>The <code>tls.CryptoStream</code> class represents a stream of encrypted data. This class 526is deprecated and should no longer be used.</p> 527<h4><code>cryptoStream.bytesWritten</code><span><a class="mark" href="#tls_cryptostream_byteswritten" id="tls_cryptostream_byteswritten">#</a></span></h4> 528<div class="api_metadata"> 529<span>Added in: v0.3.4</span><span>Deprecated since: v0.11.3</span> 530</div> 531<p>The <code>cryptoStream.bytesWritten</code> property returns the total number of bytes 532written to the underlying socket <em>including</em> the bytes required for the 533implementation of the TLS protocol.</p> 534</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> 535<div class="api_metadata"> 536<span>Added in: v0.3.2</span><span>Deprecated since: v0.11.3</span> 537</div> 538<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> 539<p>Returned by <a href="#tls_tls_createsecurepair_context_isserver_requestcert_rejectunauthorized_options"><code>tls.createSecurePair()</code></a>.</p> 540<h4>Event: <code>'secure'</code><span><a class="mark" href="#tls_event_secure" id="tls_event_secure">#</a></span></h4> 541<div class="api_metadata"> 542<span>Added in: v0.3.2</span><span>Deprecated since: v0.11.3</span> 543</div> 544<p>The <code>'secure'</code> event is emitted by the <code>SecurePair</code> object once a secure 545connection has been established.</p> 546<p>As with checking for the server 547<a href="#tls_event_secureconnection"><code>'secureConnection'</code></a> 548event, <code>pair.cleartext.authorized</code> should be inspected to confirm whether the 549certificate used is properly authorized.</p> 550</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> 551<div class="api_metadata"> 552<span>Added in: v0.3.2</span> 553</div> 554<ul> 555<li>Extends: <a href="net.html#net_class_net_server" class="type"><net.Server></a></li> 556</ul> 557<p>Accepts encrypted connections using TLS or SSL.</p> 558<h4>Event: <code>'connection'</code><span><a class="mark" href="#tls_event_connection" id="tls_event_connection">#</a></span></h4> 559<div class="api_metadata"> 560<span>Added in: v0.3.2</span> 561</div> 562<ul> 563<li><code>socket</code> <a href="stream.html#stream_class_stream_duplex" class="type"><stream.Duplex></a></li> 564</ul> 565<p>This event is emitted when a new TCP stream is established, before the TLS 566handshake begins. <code>socket</code> is typically an object of type <a href="net.html#net_class_net_socket"><code>net.Socket</code></a>. 567Usually users will not want to access this event.</p> 568<p>This event can also be explicitly emitted by users to inject connections 569into the TLS server. In that case, any <a href="stream.html#stream_class_stream_duplex"><code>Duplex</code></a> stream can be passed.</p> 570<h4>Event: <code>'keylog'</code><span><a class="mark" href="#tls_event_keylog" id="tls_event_keylog">#</a></span></h4> 571<div class="api_metadata"> 572<span>Added in: v12.3.0, v10.20.0</span> 573</div> 574<ul> 575<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> 576<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 577generated.</li> 578</ul> 579<p>The <code>keylog</code> event is emitted when key material is generated or received by 580a connection to this server (typically before handshake has completed, but not 581necessarily). This keying material can be stored for debugging, as it allows 582captured TLS traffic to be decrypted. It may be emitted multiple times for 583each socket.</p> 584<p>A typical use case is to append received lines to a common text file, which 585is later used by software (such as Wireshark) to decrypt the traffic:</p> 586<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> }); 587<span class="hljs-comment">// ...</span> 588server.<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> { 589 <span class="hljs-keyword">if</span> (tlsSocket.<span class="hljs-property">remoteAddress</span> !== <span class="hljs-string">'...'</span>) 590 <span class="hljs-keyword">return</span>; <span class="hljs-comment">// Only log keys for a particular IP</span> 591 logFile.<span class="hljs-title function_">write</span>(line); 592});</code></pre> 593<h4>Event: <code>'newSession'</code><span><a class="mark" href="#tls_event_newsession" id="tls_event_newsession">#</a></span></h4> 594<div class="api_metadata"> 595<details class="changelog"><summary>History</summary> 596<table> 597<tbody><tr><th>Version</th><th>Changes</th></tr> 598<tr><td>v0.11.12</td> 599<td><p>The <code>callback</code> argument is now supported.</p></td></tr> 600<tr><td>v0.9.2</td> 601<td><p><span>Added in: v0.9.2</span></p></td></tr> 602</tbody></table> 603</details> 604</div> 605<p>The <code>'newSession'</code> event is emitted upon creation of a new TLS session. This may 606be used to store sessions in external storage. The data should be provided to 607the <a href="#tls_event_resumesession"><code>'resumeSession'</code></a> callback.</p> 608<p>The listener callback is passed three arguments when called:</p> 609<ul> 610<li><code>sessionId</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The TLS session identifier</li> 611<li><code>sessionData</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The TLS session data</li> 612<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 613invoked in order for data to be sent or received over the secure connection.</li> 614</ul> 615<p>Listening for this event will have an effect only on connections established 616after the addition of the event listener.</p> 617<h4>Event: <code>'OCSPRequest'</code><span><a class="mark" href="#tls_event_ocsprequest" id="tls_event_ocsprequest">#</a></span></h4> 618<div class="api_metadata"> 619<span>Added in: v0.11.13</span> 620</div> 621<p>The <code>'OCSPRequest'</code> event is emitted when the client sends a certificate status 622request. The listener callback is passed three arguments when called:</p> 623<ul> 624<li><code>certificate</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The server certificate</li> 625<li><code>issuer</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The issuer's certificate</li> 626<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 627the results of the OCSP request.</li> 628</ul> 629<p>The server's current certificate can be parsed to obtain the OCSP URL 630and certificate ID; after obtaining an OCSP response, <code>callback(null, resp)</code> is 631then invoked, where <code>resp</code> is a <code>Buffer</code> instance containing the OCSP response. 632Both <code>certificate</code> and <code>issuer</code> are <code>Buffer</code> DER-representations of the 633primary and issuer's certificates. These can be used to obtain the OCSP 634certificate ID and OCSP endpoint URL.</p> 635<p>Alternatively, <code>callback(null, null)</code> may be called, indicating that there was 636no OCSP response.</p> 637<p>Calling <code>callback(err)</code> will result in a <code>socket.destroy(err)</code> call.</p> 638<p>The typical flow of an OCSP Request is as follows:</p> 639<ol> 640<li>Client connects to the server and sends an <code>'OCSPRequest'</code> (via the status 641info extension in ClientHello).</li> 642<li>Server receives the request and emits the <code>'OCSPRequest'</code> event, calling the 643listener if registered.</li> 644<li>Server extracts the OCSP URL from either the <code>certificate</code> or <code>issuer</code> and 645performs an <a href="https://en.wikipedia.org/wiki/OCSP_stapling">OCSP request</a> to the CA.</li> 646<li>Server receives <code>'OCSPResponse'</code> from the CA and sends it back to the client 647via the <code>callback</code> argument</li> 648<li>Client validates the response and either destroys the socket or performs a 649handshake.</li> 650</ol> 651<p>The <code>issuer</code> can be <code>null</code> if the certificate is either self-signed or the 652issuer is not in the root certificates list. (An issuer may be provided 653via the <code>ca</code> option when establishing the TLS connection.)</p> 654<p>Listening for this event will have an effect only on connections established 655after the addition of the event listener.</p> 656<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> 657<h4>Event: <code>'resumeSession'</code><span><a class="mark" href="#tls_event_resumesession" id="tls_event_resumesession">#</a></span></h4> 658<div class="api_metadata"> 659<span>Added in: v0.9.2</span> 660</div> 661<p>The <code>'resumeSession'</code> event is emitted when the client requests to resume a 662previous TLS session. The listener callback is passed two arguments when 663called:</p> 664<ul> 665<li><code>sessionId</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The TLS session identifier</li> 666<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 667has been recovered: <code>callback([err[, sessionData]])</code> 668<ul> 669<li><code>err</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a></li> 670<li><code>sessionData</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 671</ul> 672</li> 673</ul> 674<p>The event listener should perform a lookup in external storage for the 675<code>sessionData</code> saved by the <a href="#tls_event_newsession"><code>'newSession'</code></a> event handler using the given 676<code>sessionId</code>. If found, call <code>callback(null, sessionData)</code> to resume the session. 677If not found, the session cannot be resumed. <code>callback()</code> must be called 678without <code>sessionData</code> so that the handshake can continue and a new session can 679be created. It is possible to call <code>callback(err)</code> to terminate the incoming 680connection and destroy the socket.</p> 681<p>Listening for this event will have an effect only on connections established 682after the addition of the event listener.</p> 683<p>The following illustrates resuming a TLS session:</p> 684<pre><code class="language-js"><span class="hljs-keyword">const</span> tlsSessionStore = {}; 685server.<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> { 686 tlsSessionStore[id.<span class="hljs-title function_">toString</span>(<span class="hljs-string">'hex'</span>)] = data; 687 <span class="hljs-title function_">cb</span>(); 688}); 689server.<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> { 690 <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>); 691});</code></pre> 692<h4>Event: <code>'secureConnection'</code><span><a class="mark" href="#tls_event_secureconnection" id="tls_event_secureconnection">#</a></span></h4> 693<div class="api_metadata"> 694<span>Added in: v0.3.2</span> 695</div> 696<p>The <code>'secureConnection'</code> event is emitted after the handshaking process for a 697new connection has successfully completed. The listener callback is passed a 698single argument when called:</p> 699<ul> 700<li><code>tlsSocket</code> <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a> The established TLS socket.</li> 701</ul> 702<p>The <code>tlsSocket.authorized</code> property is a <code>boolean</code> indicating whether the 703client has been verified by one of the supplied Certificate Authorities for the 704server. If <code>tlsSocket.authorized</code> is <code>false</code>, then <code>socket.authorizationError</code> 705is set to describe how authorization failed. Depending on the settings 706of the TLS server, unauthorized connections may still be accepted.</p> 707<p>The <code>tlsSocket.alpnProtocol</code> property is a string that contains the selected 708ALPN protocol. When ALPN has no selected protocol, <code>tlsSocket.alpnProtocol</code> 709equals <code>false</code>.</p> 710<p>The <code>tlsSocket.servername</code> property is a string containing the server name 711requested via SNI.</p> 712<h4>Event: <code>'tlsClientError'</code><span><a class="mark" href="#tls_event_tlsclienterror" id="tls_event_tlsclienterror">#</a></span></h4> 713<div class="api_metadata"> 714<span>Added in: v6.0.0</span> 715</div> 716<p>The <code>'tlsClientError'</code> event is emitted when an error occurs before a secure 717connection is established. The listener callback is passed two arguments when 718called:</p> 719<ul> 720<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> 721<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 722error originated.</li> 723</ul> 724<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> 725<div class="api_metadata"> 726<span>Added in: v0.5.3</span> 727</div> 728<ul> 729<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> 730<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 731from the <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> <code>options</code> arguments (e.g. <code>key</code>, 732<code>cert</code>, <code>ca</code>, etc).</li> 733</ul> 734<p>The <code>server.addContext()</code> method adds a secure context that will be used if 735the client request's SNI name matches the supplied <code>hostname</code> (or wildcard).</p> 736<h4><code>server.address()</code><span><a class="mark" href="#tls_server_address" id="tls_server_address">#</a></span></h4> 737<div class="api_metadata"> 738<span>Added in: v0.6.0</span> 739</div> 740<ul> 741<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 742</ul> 743<p>Returns the bound address, the address family name, and port of the 744server as reported by the operating system. See <a href="net.html#net_server_address"><code>net.Server.address()</code></a> for 745more information.</p> 746<h4><code>server.close([callback])</code><span><a class="mark" href="#tls_server_close_callback" id="tls_server_close_callback">#</a></span></h4> 747<div class="api_metadata"> 748<span>Added in: v0.3.2</span> 749</div> 750<ul> 751<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 752for the server instance's <code>'close'</code> event.</li> 753<li>Returns: <a href="tls.html#tls_class_tls_server" class="type"><tls.Server></a></li> 754</ul> 755<p>The <code>server.close()</code> method stops the server from accepting new connections.</p> 756<p>This function operates asynchronously. The <code>'close'</code> event will be emitted 757when the server has no more open connections.</p> 758<h4><code>server.connections</code><span><a class="mark" href="#tls_server_connections" id="tls_server_connections">#</a></span></h4> 759<div class="api_metadata"> 760<span>Added in: v0.3.2</span><span>Deprecated since: v0.9.7</span> 761</div> 762<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> 763<ul> 764<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 765</ul> 766<p>Returns the current number of concurrent connections on the server.</p> 767<h4><code>server.getTicketKeys()</code><span><a class="mark" href="#tls_server_getticketkeys" id="tls_server_getticketkeys">#</a></span></h4> 768<div class="api_metadata"> 769<span>Added in: v3.0.0</span> 770</div> 771<ul> 772<li>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A 48-byte buffer containing the session ticket keys.</li> 773</ul> 774<p>Returns the session ticket keys.</p> 775<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 776<h4><code>server.listen()</code><span><a class="mark" href="#tls_server_listen" id="tls_server_listen">#</a></span></h4> 777<p>Starts the server listening for encrypted connections. 778This 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> 779<h4><code>server.setSecureContext(options)</code><span><a class="mark" href="#tls_server_setsecurecontext_options" id="tls_server_setsecurecontext_options">#</a></span></h4> 780<div class="api_metadata"> 781<span>Added in: v11.0.0</span> 782</div> 783<ul> 784<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 785the <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> <code>options</code> arguments (e.g. <code>key</code>, <code>cert</code>, 786<code>ca</code>, etc).</li> 787</ul> 788<p>The <code>server.setSecureContext()</code> method replaces the secure context of an 789existing server. Existing connections to the server are not interrupted.</p> 790<h4><code>server.setTicketKeys(keys)</code><span><a class="mark" href="#tls_server_setticketkeys_keys" id="tls_server_setticketkeys_keys">#</a></span></h4> 791<div class="api_metadata"> 792<span>Added in: v3.0.0</span> 793</div> 794<ul> 795<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 796ticket keys.</li> 797</ul> 798<p>Sets the session ticket keys.</p> 799<p>Changes to the ticket keys are effective only for future server connections. 800Existing or currently pending server connections will use the previous keys.</p> 801<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 802</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> 803<div class="api_metadata"> 804<span>Added in: v0.11.4</span> 805</div> 806<ul> 807<li>Extends: <a href="net.html#net_class_net_socket" class="type"><net.Socket></a></li> 808</ul> 809<p>Performs transparent encryption of written data and all required TLS 810negotiation.</p> 811<p>Instances of <code>tls.TLSSocket</code> implement the duplex <a href="stream.html#stream_stream">Stream</a> interface.</p> 812<p>Methods that return TLS connection metadata (e.g. 813<a href="#tls_tlssocket_getpeercertificate_detailed"><code>tls.TLSSocket.getPeerCertificate()</code></a> will only return data while the 814connection is open.</p> 815<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> 816<div class="api_metadata"> 817<details class="changelog"><summary>History</summary> 818<table> 819<tbody><tr><th>Version</th><th>Changes</th></tr> 820<tr><td>v12.2.0</td> 821<td><p>The <code>enableTrace</code> option is now supported.</p></td></tr> 822<tr><td>v5.0.0</td> 823<td><p>ALPN options are supported now.</p></td></tr> 824<tr><td>v0.11.4</td> 825<td><p><span>Added in: v0.11.4</span></p></td></tr> 826</tbody></table> 827</details> 828</div> 829<ul> 830<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> 831On the server side, any <code>Duplex</code> stream. On the client side, any 832instance of <a href="net.html#net_class_net_socket"><code>net.Socket</code></a> (for generic <code>Duplex</code> stream support 833on the client side, <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> must be used).</li> 834<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 835<ul> 836<li><code>enableTrace</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 837<li><code>isServer</code>: The SSL/TLS protocol is asymmetrical, TLSSockets must know if 838they are to behave as a server or a client. If <code>true</code> the TLS socket will be 839instantiated as a server. <strong>Default:</strong> <code>false</code>.</li> 840<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> 841<li><code>requestCert</code>: Whether to authenticate the remote peer by requesting a 842certificate. Clients always request a server certificate. Servers 843(<code>isServer</code> is true) may set <code>requestCert</code> to true to request a client 844certificate.</li> 845<li><code>rejectUnauthorized</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 846<li><code>ALPNProtocols</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 847<li><code>SNICallback</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 848<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> 849<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 850extension will be added to the client hello and an <code>'OCSPResponse'</code> event 851will be emitted on the socket before establishing a secure communication</li> 852<li><code>secureContext</code>: TLS context object created with 853<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. If a <code>secureContext</code> is <em>not</em> provided, one 854will be created by passing the entire <code>options</code> object to 855<code>tls.createSecureContext()</code>.</li> 856<li>...: <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> options that are used if the 857<code>secureContext</code> option is missing. Otherwise, they are ignored.</li> 858</ul> 859</li> 860</ul> 861<p>Construct a new <code>tls.TLSSocket</code> object from an existing TCP socket.</p> 862<h4>Event: <code>'keylog'</code><span><a class="mark" href="#tls_event_keylog_1" id="tls_event_keylog_1">#</a></span></h4> 863<div class="api_metadata"> 864<span>Added in: v12.3.0, v10.20.0</span> 865</div> 866<ul> 867<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> 868</ul> 869<p>The <code>keylog</code> event is emitted on a <code>tls.TLSSocket</code> when key material 870is generated or received by the socket. This keying material can be stored 871for debugging, as it allows captured TLS traffic to be decrypted. It may 872be emitted multiple times, before or after the handshake completes.</p> 873<p>A typical use case is to append received lines to a common text file, which 874is later used by software (such as Wireshark) to decrypt the traffic:</p> 875<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> }); 876<span class="hljs-comment">// ...</span> 877tlsSocket.<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> 878<h4>Event: <code>'OCSPResponse'</code><span><a class="mark" href="#tls_event_ocspresponse" id="tls_event_ocspresponse">#</a></span></h4> 879<div class="api_metadata"> 880<span>Added in: v0.11.13</span> 881</div> 882<p>The <code>'OCSPResponse'</code> event is emitted if the <code>requestOCSP</code> option was set 883when the <code>tls.TLSSocket</code> was created and an OCSP response has been received. 884The listener callback is passed a single argument when called:</p> 885<ul> 886<li><code>response</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The server's OCSP response</li> 887</ul> 888<p>Typically, the <code>response</code> is a digitally signed object from the server's CA that 889contains information about server's certificate revocation status.</p> 890<h4>Event: <code>'secureConnect'</code><span><a class="mark" href="#tls_event_secureconnect" id="tls_event_secureconnect">#</a></span></h4> 891<div class="api_metadata"> 892<span>Added in: v0.11.4</span> 893</div> 894<p>The <code>'secureConnect'</code> event is emitted after the handshaking process for a new 895connection has successfully completed. The listener callback will be called 896regardless of whether or not the server's certificate has been authorized. It 897is the client's responsibility to check the <code>tlsSocket.authorized</code> property to 898determine if the server certificate was signed by one of the specified CAs. If 899<code>tlsSocket.authorized === false</code>, then the error can be found by examining the 900<code>tlsSocket.authorizationError</code> property. If ALPN was used, the 901<code>tlsSocket.alpnProtocol</code> property can be checked to determine the negotiated 902protocol.</p> 903<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 904using the <code>new tls.TLSSocket()</code> constructor.</p> 905<h4>Event: <code>'session'</code><span><a class="mark" href="#tls_event_session" id="tls_event_session">#</a></span></h4> 906<div class="api_metadata"> 907<span>Added in: v11.10.0</span> 908</div> 909<ul> 910<li><code>session</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 911</ul> 912<p>The <code>'session'</code> event is emitted on a client <code>tls.TLSSocket</code> when a new session 913or TLS ticket is available. This may or may not be before the handshake is 914complete, depending on the TLS protocol version that was negotiated. The event 915is not emitted on the server, or if a new session was not created, for example, 916when the connection was resumed. For some TLS protocol versions the event may be 917emitted multiple times, in which case all the sessions can be used for 918resumption.</p> 919<p>On the client, the <code>session</code> can be provided to the <code>session</code> option of 920<a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> to resume the connection.</p> 921<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 922<p>For TLSv1.2 and below, <a href="#tls_tlssocket_getsession"><code>tls.TLSSocket.getSession()</code></a> can be called once 923the handshake is complete. For TLSv1.3, only ticket-based resumption is allowed 924by the protocol, multiple tickets are sent, and the tickets aren't sent until 925after the handshake completes. So it is necessary to wait for the 926<code>'session'</code> event to get a resumable session. Applications 927should use the <code>'session'</code> event instead of <code>getSession()</code> to ensure 928they will work for all TLS versions. Applications that only expect to 929get or use one session should listen for this event only once:</p> 930<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> { 931 <span class="hljs-comment">// The session can be used immediately or later.</span> 932 tls.<span class="hljs-title function_">connect</span>({ 933 <span class="hljs-attr">session</span>: session, 934 <span class="hljs-comment">// Other connect options...</span> 935 }); 936});</code></pre> 937<h4><code>tlsSocket.address()</code><span><a class="mark" href="#tls_tlssocket_address" id="tls_tlssocket_address">#</a></span></h4> 938<div class="api_metadata"> 939<span>Added in: v0.11.4</span> 940</div> 941<ul> 942<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 943</ul> 944<p>Returns the bound <code>address</code>, the address <code>family</code> name, and <code>port</code> of the 945underlying socket as reported by the operating system: 946<code>{ port: 12346, family: 'IPv4', address: '127.0.0.1' }</code>.</p> 947<h4><code>tlsSocket.authorizationError</code><span><a class="mark" href="#tls_tlssocket_authorizationerror" id="tls_tlssocket_authorizationerror">#</a></span></h4> 948<div class="api_metadata"> 949<span>Added in: v0.11.4</span> 950</div> 951<p>Returns the reason why the peer's certificate was not been verified. This 952property is set only when <code>tlsSocket.authorized === false</code>.</p> 953<h4><code>tlsSocket.authorized</code><span><a class="mark" href="#tls_tlssocket_authorized" id="tls_tlssocket_authorized">#</a></span></h4> 954<div class="api_metadata"> 955<span>Added in: v0.11.4</span> 956</div> 957<ul> 958<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 959</ul> 960<p>Returns <code>true</code> if the peer certificate was signed by one of the CAs specified 961when creating the <code>tls.TLSSocket</code> instance, otherwise <code>false</code>.</p> 962<h4><code>tlsSocket.disableRenegotiation()</code><span><a class="mark" href="#tls_tlssocket_disablerenegotiation" id="tls_tlssocket_disablerenegotiation">#</a></span></h4> 963<div class="api_metadata"> 964<span>Added in: v8.4.0</span> 965</div> 966<p>Disables TLS renegotiation for this <code>TLSSocket</code> instance. Once called, attempts 967to renegotiate will trigger an <code>'error'</code> event on the <code>TLSSocket</code>.</p> 968<h4><code>tlsSocket.enableTrace()</code><span><a class="mark" href="#tls_tlssocket_enabletrace" id="tls_tlssocket_enabletrace">#</a></span></h4> 969<div class="api_metadata"> 970<span>Added in: v12.2.0</span> 971</div> 972<p>When enabled, TLS packet trace information is written to <code>stderr</code>. This can be 973used to debug TLS connection problems.</p> 974<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 975<code>SSL_trace()</code> function, the format is undocumented, can change without notice, 976and should not be relied on.</p> 977<h4><code>tlsSocket.encrypted</code><span><a class="mark" href="#tls_tlssocket_encrypted" id="tls_tlssocket_encrypted">#</a></span></h4> 978<div class="api_metadata"> 979<span>Added in: v0.11.4</span> 980</div> 981<p>Always returns <code>true</code>. This may be used to distinguish TLS sockets from regular 982<code>net.Socket</code> instances.</p> 983<h4><code>tlsSocket.getCertificate()</code><span><a class="mark" href="#tls_tlssocket_getcertificate" id="tls_tlssocket_getcertificate">#</a></span></h4> 984<div class="api_metadata"> 985<span>Added in: v11.2.0</span> 986</div> 987<ul> 988<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 989</ul> 990<p>Returns an object representing the local certificate. The returned object has 991some properties corresponding to the fields of the certificate.</p> 992<p>See <a href="#tls_tlssocket_getpeercertificate_detailed"><code>tls.TLSSocket.getPeerCertificate()</code></a> for an example of the certificate 993structure.</p> 994<p>If there is no local certificate, an empty object will be returned. If the 995socket has been destroyed, <code>null</code> will be returned.</p> 996<h4><code>tlsSocket.getCipher()</code><span><a class="mark" href="#tls_tlssocket_getcipher" id="tls_tlssocket_getcipher">#</a></span></h4> 997<div class="api_metadata"> 998<details class="changelog"><summary>History</summary> 999<table> 1000<tbody><tr><th>Version</th><th>Changes</th></tr> 1001<tr><td>v13.4.0, v12.16.0</td> 1002<td><p>Return the IETF cipher name as <code>standardName</code>.</p></td></tr> 1003<tr><td>v12.0.0</td> 1004<td><p>Return the minimum cipher version, instead of a fixed string (<code>'TLSv1/SSLv3'</code>).</p></td></tr> 1005<tr><td>v0.11.4</td> 1006<td><p><span>Added in: v0.11.4</span></p></td></tr> 1007</tbody></table> 1008</details> 1009</div> 1010<ul> 1011<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1012<ul> 1013<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> 1014<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> 1015<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 1016suite.</li> 1017</ul> 1018</li> 1019</ul> 1020<p>Returns an object containing information on the negotiated cipher suite.</p> 1021<p>For example:</p> 1022<pre><code class="language-json"><span class="hljs-punctuation">{</span> 1023 <span class="hljs-attr">"name"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"AES128-SHA256"</span><span class="hljs-punctuation">,</span> 1024 <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> 1025 <span class="hljs-attr">"version"</span><span class="hljs-punctuation">:</span> <span class="hljs-string">"TLSv1.2"</span> 1026<span class="hljs-punctuation">}</span></code></pre> 1027<p>See 1028<a href="https://www.openssl.org/docs/man1.1.1/man3/SSL_CIPHER_get_name.html">SSL_CIPHER_get_name</a> 1029for more information.</p> 1030<h4><code>tlsSocket.getEphemeralKeyInfo()</code><span><a class="mark" href="#tls_tlssocket_getephemeralkeyinfo" id="tls_tlssocket_getephemeralkeyinfo">#</a></span></h4> 1031<div class="api_metadata"> 1032<span>Added in: v5.0.0</span> 1033</div> 1034<ul> 1035<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 1036</ul> 1037<p>Returns an object representing the type, name, and size of parameter of 1038an ephemeral key exchange in <a href="#tls_perfect_forward_secrecy">perfect forward secrecy</a> on a client 1039connection. It returns an empty object when the key exchange is not 1040ephemeral. As this is only supported on a client socket; <code>null</code> is returned 1041if called on a server socket. The supported types are <code>'DH'</code> and <code>'ECDH'</code>. The 1042<code>name</code> property is available only when type is <code>'ECDH'</code>.</p> 1043<p>For example: <code>{ type: 'ECDH', name: 'prime256v1', size: 256 }</code>.</p> 1044<h4><code>tlsSocket.getFinished()</code><span><a class="mark" href="#tls_tlssocket_getfinished" id="tls_tlssocket_getfinished">#</a></span></h4> 1045<div class="api_metadata"> 1046<span>Added in: v9.9.0</span> 1047</div> 1048<ul> 1049<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 1050sent to the socket as part of a SSL/TLS handshake, or <code>undefined</code> if 1051no <code>Finished</code> message has been sent yet.</li> 1052</ul> 1053<p>As the <code>Finished</code> messages are message digests of the complete handshake 1054(with a total of 192 bits for TLS 1.0 and more for SSL 3.0), they can 1055be used for external authentication procedures when the authentication 1056provided by SSL/TLS is not desired or is not enough.</p> 1057<p>Corresponds to the <code>SSL_get_finished</code> routine in OpenSSL and may be used 1058to implement the <code>tls-unique</code> channel binding from <a href="https://tools.ietf.org/html/rfc5929">RFC 5929</a>.</p> 1059<h4><code>tlsSocket.getPeerCertificate([detailed])</code><span><a class="mark" href="#tls_tlssocket_getpeercertificate_detailed" id="tls_tlssocket_getpeercertificate_detailed">#</a></span></h4> 1060<div class="api_metadata"> 1061<span>Added in: v0.11.4</span> 1062</div> 1063<ul> 1064<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 1065include just the peer's certificate.</li> 1066<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> 1067</ul> 1068<p>Returns an object representing the peer's certificate. If the peer does not 1069provide a certificate, an empty object will be returned. If the socket has been 1070destroyed, <code>null</code> will be returned.</p> 1071<p>If the full certificate chain was requested, each certificate will include an 1072<code>issuerCertificate</code> property containing an object representing its issuer's 1073certificate.</p> 1074<h5>Certificate object<span><a class="mark" href="#tls_certificate_object" id="tls_certificate_object">#</a></span></h5> 1075<div class="api_metadata"> 1076<details class="changelog"><summary>History</summary> 1077<table> 1078<tbody><tr><th>Version</th><th>Changes</th></tr> 1079<tr><td>v11.4.0</td> 1080<td><p>Support Elliptic Curve public key info.</p></td></tr> 1081</tbody></table> 1082</details> 1083</div> 1084<p>A certificate object has properties corresponding to the fields of the 1085certificate.</p> 1086<ul> 1087<li><code>raw</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The DER encoded X.509 certificate data.</li> 1088<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 1089Country (<code>C:</code>), StateOrProvince (<code>ST</code>), Locality (<code>L</code>), Organization (<code>O</code>), 1090OrganizationalUnit (<code>OU</code>), and CommonName (<code>CN</code>). The CommonName is typically 1091a DNS name with TLS certificates. Example: 1092<code>{C: 'UK', ST: 'BC', L: 'Metro', O: 'Node Fans', OU: 'Docs', CN: 'example.com'}</code>.</li> 1093<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 1094<code>subject</code>.</li> 1095<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> 1096<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> 1097<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. 1098Example: <code>'B9B0D332A1AA5635'</code>.</li> 1099<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 1100returned as a <code>:</code> separated hexadecimal string. Example: <code>'2A:7A:C2:DD:...'</code>.</li> 1101<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. 1102It is returned as a <code>:</code> separated hexadecimal string. Example: 1103<code>'2A:7A:C2:DD:...'</code>.</li> 1104<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> 1105<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 1106for the subject, an alternative to the <code>subject</code> names.</li> 1107<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, 1108used with OCSP.</li> 1109<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 1110self-signed certificates, this may be a circular reference.</li> 1111</ul> 1112<p>The certificate may contain information about the public key, depending on 1113the key type.</p> 1114<p>For RSA keys, the following properties may be defined:</p> 1115<ul> 1116<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> 1117<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 1118notation. Example: <code>'0x010001'</code>.</li> 1119<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: 1120<code>'B56CE45CB7...'</code>.</li> 1121<li><code>pubkey</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The public key.</li> 1122</ul> 1123<p>For EC keys, the following properties may be defined:</p> 1124<ul> 1125<li><code>pubkey</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> The public key.</li> 1126<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> 1127<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 1128curve. Well-known curves are identified by an OID. While it is unusual, it is 1129possible that the curve is identified by its mathematical properties, in which 1130case it will not have an OID. Example: <code>'prime256v1'</code>.</li> 1131<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 1132has one (not all well-known curves have been assigned names by NIST). Example: 1133<code>'P-256'</code>.</li> 1134</ul> 1135<p>Example certificate:</p> 1136<!-- eslint-skip --> 1137<pre><code class="language-js">{ <span class="hljs-attr">subject</span>: 1138 { <span class="hljs-attr">OU</span>: [ <span class="hljs-string">'Domain Control Validated'</span>, <span class="hljs-string">'PositiveSSL Wildcard'</span> ], 1139 <span class="hljs-attr">CN</span>: <span class="hljs-string">'*.nodejs.org'</span> }, 1140 <span class="hljs-attr">issuer</span>: 1141 { <span class="hljs-attr">C</span>: <span class="hljs-string">'GB'</span>, 1142 <span class="hljs-attr">ST</span>: <span class="hljs-string">'Greater Manchester'</span>, 1143 <span class="hljs-attr">L</span>: <span class="hljs-string">'Salford'</span>, 1144 <span class="hljs-attr">O</span>: <span class="hljs-string">'COMODO CA Limited'</span>, 1145 <span class="hljs-attr">CN</span>: <span class="hljs-string">'COMODO RSA Domain Validation Secure Server CA'</span> }, 1146 <span class="hljs-attr">subjectaltname</span>: <span class="hljs-string">'DNS:*.nodejs.org, DNS:nodejs.org'</span>, 1147 <span class="hljs-attr">infoAccess</span>: 1148 { <span class="hljs-string">'CA Issuers - URI'</span>: 1149 [ <span class="hljs-string">'http://crt.comodoca.com/COMODORSADomainValidationSecureServerCA.crt'</span> ], 1150 <span class="hljs-string">'OCSP - URI'</span>: [ <span class="hljs-string">'http://ocsp.comodoca.com'</span> ] }, 1151 <span class="hljs-attr">modulus</span>: <span class="hljs-string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span>, 1152 <span class="hljs-attr">exponent</span>: <span class="hljs-string">'0x10001'</span>, 1153 <span class="hljs-attr">pubkey</span>: <Buffer ... >, 1154 valid_from: 'Aug 14 00:00:00 2017 GMT', 1155 valid_to: 'Nov 20 23:59:59 2019 GMT', 1156 fingerprint: '01:02:59:D9:C3:D2:0D:08:F7:82:4E:44:A4:B4:53:C5:E2:3A:87:4D', 1157 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', 1158 ext_key_usage: [ '1.3.6.1.5.5.7.3.1', '1.3.6.1.5.5.7.3.2' ], 1159 serialNumber: '66593D57F20CBC573E433381B5FEC280', 1160 raw: <Buffer ... > }</code></pre> 1161<h4><code>tlsSocket.getPeerFinished()</code><span><a class="mark" href="#tls_tlssocket_getpeerfinished" id="tls_tlssocket_getpeerfinished">#</a></span></h4> 1162<div class="api_metadata"> 1163<span>Added in: v9.9.0</span> 1164</div> 1165<ul> 1166<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 1167or has actually been received from the socket as part of a SSL/TLS handshake, 1168or <code>undefined</code> if there is no <code>Finished</code> message so far.</li> 1169</ul> 1170<p>As the <code>Finished</code> messages are message digests of the complete handshake 1171(with a total of 192 bits for TLS 1.0 and more for SSL 3.0), they can 1172be used for external authentication procedures when the authentication 1173provided by SSL/TLS is not desired or is not enough.</p> 1174<p>Corresponds to the <code>SSL_get_peer_finished</code> routine in OpenSSL and may be used 1175to implement the <code>tls-unique</code> channel binding from <a href="https://tools.ietf.org/html/rfc5929">RFC 5929</a>.</p> 1176<h4><code>tlsSocket.getProtocol()</code><span><a class="mark" href="#tls_tlssocket_getprotocol" id="tls_tlssocket_getprotocol">#</a></span></h4> 1177<div class="api_metadata"> 1178<span>Added in: v5.7.0</span> 1179</div> 1180<ul> 1181<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> 1182</ul> 1183<p>Returns a string containing the negotiated SSL/TLS protocol version of the 1184current connection. The value <code>'unknown'</code> will be returned for connected 1185sockets that have not completed the handshaking process. The value <code>null</code> will 1186be returned for server sockets or disconnected client sockets.</p> 1187<p>Protocol versions are:</p> 1188<ul> 1189<li><code>'SSLv3'</code></li> 1190<li><code>'TLSv1'</code></li> 1191<li><code>'TLSv1.1'</code></li> 1192<li><code>'TLSv1.2'</code></li> 1193<li><code>'TLSv1.3'</code></li> 1194</ul> 1195<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> 1196<h4><code>tlsSocket.getSession()</code><span><a class="mark" href="#tls_tlssocket_getsession" id="tls_tlssocket_getsession">#</a></span></h4> 1197<div class="api_metadata"> 1198<span>Added in: v0.11.4</span> 1199</div> 1200<ul> 1201<li><a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 1202</ul> 1203<p>Returns the TLS session data or <code>undefined</code> if no session was 1204negotiated. On the client, the data can be provided to the <code>session</code> option of 1205<a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> to resume the connection. On the server, it may be useful 1206for debugging.</p> 1207<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 1208<p>Note: <code>getSession()</code> works only for TLSv1.2 and below. For TLSv1.3, applications 1209must use the <a href="#tls_event_session"><code>'session'</code></a> event (it also works for TLSv1.2 and below).</p> 1210<h4><code>tlsSocket.getSharedSigalgs()</code><span><a class="mark" href="#tls_tlssocket_getsharedsigalgs" id="tls_tlssocket_getsharedsigalgs">#</a></span></h4> 1211<div class="api_metadata"> 1212<span>Added in: v12.11.0</span> 1213</div> 1214<ul> 1215<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 1216the client in the order of decreasing preference.</li> 1217</ul> 1218<p>See 1219<a href="https://www.openssl.org/docs/man1.1.1/man3/SSL_get_shared_sigalgs.html">SSL_get_shared_sigalgs</a> 1220for more information.</p> 1221<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> 1222<div class="api_metadata"> 1223<span>Added in: v13.10.0</span> 1224</div> 1225<ul> 1226<li> 1227<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> 1228</li> 1229<li> 1230<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 1231value from the 1232<a href="https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#exporter-labels">IANA Exporter Label Registry</a>.</p> 1233</li> 1234<li> 1235<p><code>context</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> Optionally provide a context.</p> 1236</li> 1237<li> 1238<p>Returns: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> requested bytes of the keying material</p> 1239</li> 1240</ul> 1241<p>Keying material is used for validations to prevent different kind of attacks in 1242network protocols, for example in the specifications of IEEE 802.1X.</p> 1243<p>Example</p> 1244<pre><code class="language-js"><span class="hljs-keyword">const</span> keyingMaterial = tlsSocket.<span class="hljs-title function_">exportKeyingMaterial</span>( 1245 <span class="hljs-number">128</span>, 1246 <span class="hljs-string">'client finished'</span>); 1247 1248<span class="hljs-comment">/** 1249 Example return value of keyingMaterial: 1250 <Buffer 76 26 af 99 c5 56 8e 42 09 91 ef 9f 93 cb ad 6c 7b 65 f8 53 f1 d8 d9 1251 12 5a 33 b8 b5 25 df 7b 37 9f e0 e2 4f b8 67 83 a3 2f cd 5d 41 42 4c 91 1252 74 ef 2c ... 78 more bytes> 1253*/</span></code></pre> 1254<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 1255information.</p> 1256<h4><code>tlsSocket.getTLSTicket()</code><span><a class="mark" href="#tls_tlssocket_gettlsticket" id="tls_tlssocket_gettlsticket">#</a></span></h4> 1257<div class="api_metadata"> 1258<span>Added in: v0.11.4</span> 1259</div> 1260<ul> 1261<li><a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a></li> 1262</ul> 1263<p>For a client, returns the TLS session ticket if one is available, or 1264<code>undefined</code>. For a server, always returns <code>undefined</code>.</p> 1265<p>It may be useful for debugging.</p> 1266<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 1267<h4><code>tlsSocket.isSessionReused()</code><span><a class="mark" href="#tls_tlssocket_issessionreused" id="tls_tlssocket_issessionreused">#</a></span></h4> 1268<div class="api_metadata"> 1269<span>Added in: v0.5.6</span> 1270</div> 1271<ul> 1272<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> 1273</ul> 1274<p>See <a href="#tls_session_resumption">Session Resumption</a> for more information.</p> 1275<h4><code>tlsSocket.localAddress</code><span><a class="mark" href="#tls_tlssocket_localaddress" id="tls_tlssocket_localaddress">#</a></span></h4> 1276<div class="api_metadata"> 1277<span>Added in: v0.11.4</span> 1278</div> 1279<ul> 1280<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1281</ul> 1282<p>Returns the string representation of the local IP address.</p> 1283<h4><code>tlsSocket.localPort</code><span><a class="mark" href="#tls_tlssocket_localport" id="tls_tlssocket_localport">#</a></span></h4> 1284<div class="api_metadata"> 1285<span>Added in: v0.11.4</span> 1286</div> 1287<ul> 1288<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 1289</ul> 1290<p>Returns the numeric representation of the local port.</p> 1291<h4><code>tlsSocket.remoteAddress</code><span><a class="mark" href="#tls_tlssocket_remoteaddress" id="tls_tlssocket_remoteaddress">#</a></span></h4> 1292<div class="api_metadata"> 1293<span>Added in: v0.11.4</span> 1294</div> 1295<ul> 1296<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1297</ul> 1298<p>Returns the string representation of the remote IP address. For example, 1299<code>'74.125.127.100'</code> or <code>'2001:4860:a005::68'</code>.</p> 1300<h4><code>tlsSocket.remoteFamily</code><span><a class="mark" href="#tls_tlssocket_remotefamily" id="tls_tlssocket_remotefamily">#</a></span></h4> 1301<div class="api_metadata"> 1302<span>Added in: v0.11.4</span> 1303</div> 1304<ul> 1305<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1306</ul> 1307<p>Returns the string representation of the remote IP family. <code>'IPv4'</code> or <code>'IPv6'</code>.</p> 1308<h4><code>tlsSocket.remotePort</code><span><a class="mark" href="#tls_tlssocket_remoteport" id="tls_tlssocket_remoteport">#</a></span></h4> 1309<div class="api_metadata"> 1310<span>Added in: v0.11.4</span> 1311</div> 1312<ul> 1313<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 1314</ul> 1315<p>Returns the numeric representation of the remote port. For example, <code>443</code>.</p> 1316<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> 1317<div class="api_metadata"> 1318<span>Added in: v0.11.8</span> 1319</div> 1320<ul> 1321<li> 1322<p><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></p> 1323<ul> 1324<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 1325verified against the list of supplied CAs. An <code>'error'</code> event is emitted if 1326verification fails; <code>err.code</code> contains the OpenSSL error code. <strong>Default:</strong> 1327<code>true</code>.</li> 1328<li><code>requestCert</code></li> 1329</ul> 1330</li> 1331<li> 1332<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 1333attached once to the <code>'secure'</code> event. If <code>renegotiate()</code> returned <code>false</code>, 1334<code>callback</code> will be called in the next tick with an error, unless the 1335<code>tlsSocket</code> has been destroyed, in which case <code>callback</code> will not be called 1336at all.</p> 1337</li> 1338<li> 1339<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> 1340</li> 1341</ul> 1342<p>The <code>tlsSocket.renegotiate()</code> method initiates a TLS renegotiation process. 1343Upon completion, the <code>callback</code> function will be passed a single argument 1344that is either an <code>Error</code> (if the request failed) or <code>null</code>.</p> 1345<p>This method can be used to request a peer's certificate after the secure 1346connection has been established.</p> 1347<p>When running as the server, the socket will be destroyed with an error after 1348<code>handshakeTimeout</code> timeout.</p> 1349<p>For TLSv1.3, renegotiation cannot be initiated, it is not supported by the 1350protocol.</p> 1351<h4><code>tlsSocket.setMaxSendFragment(size)</code><span><a class="mark" href="#tls_tlssocket_setmaxsendfragment_size" id="tls_tlssocket_setmaxsendfragment_size">#</a></span></h4> 1352<div class="api_metadata"> 1353<span>Added in: v0.11.11</span> 1354</div> 1355<ul> 1356<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>. 1357<strong>Default:</strong> <code>16384</code>.</li> 1358<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 1359</ul> 1360<p>The <code>tlsSocket.setMaxSendFragment()</code> method sets the maximum TLS fragment size. 1361Returns <code>true</code> if setting the limit succeeded; <code>false</code> otherwise.</p> 1362<p>Smaller fragment sizes decrease the buffering latency on the client: larger 1363fragments are buffered by the TLS layer until the entire fragment is received 1364and its integrity is verified; large fragments can span multiple roundtrips 1365and their processing can be delayed due to packet loss or reordering. However, 1366smaller fragments add extra TLS framing bytes and CPU overhead, which may 1367decrease overall server throughput.</p> 1368</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> 1369<div class="api_metadata"> 1370<details class="changelog"><summary>History</summary> 1371<table> 1372<tbody><tr><th>Version</th><th>Changes</th></tr> 1373<tr><td>v14.18.3</td> 1374<td><p>Support for <code>uniformResourceIdentifier</code> subject alternative names has been disabled in response to CVE-2021-44531.</p></td></tr> 1375<tr><td>v0.8.4</td> 1376<td><p><span>Added in: v0.8.4</span></p></td></tr> 1377</tbody></table> 1378</details> 1379</div> 1380<ul> 1381<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 1382against.</li> 1383<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> 1384<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> 1385</ul> 1386<p>Verifies the certificate <code>cert</code> is issued to <code>hostname</code>.</p> 1387<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 1388failure. On success, returns <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type" class="type"><undefined></a>.</p> 1389<p>This function can be overwritten by providing alternative function as part of 1390the <code>options.checkServerIdentity</code> option passed to <code>tls.connect()</code>. The 1391overwriting function can call <code>tls.checkServerIdentity()</code> of course, to augment 1392the checks done with additional verification.</p> 1393<p>This function is only called if the certificate passed all other checks, such as 1394being issued by trusted CA (<code>options.ca</code>).</p> 1395<p>Earlier versions of Node.js incorrectly accepted certificates for a given 1396<code>hostname</code> if a matching <code>uniformResourceIdentifier</code> subject alternative name 1397was 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 1398<code>uniformResourceIdentifier</code> subject alternative names can use a custom 1399<code>options.checkServerIdentity</code> function that implements the desired behavior.</p> 1400</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> 1401<div class="api_metadata"> 1402<details class="changelog"><summary>History</summary> 1403<table> 1404<tbody><tr><th>Version</th><th>Changes</th></tr> 1405<tr><td>v14.18.0</td> 1406<td><p>Added <code>onread</code> option.</p></td></tr> 1407<tr><td>v14.1.0</td> 1408<td><p>The <code>highWaterMark</code> option is accepted now.</p></td></tr> 1409<tr><td>v13.6.0, v12.16.0</td> 1410<td><p>The <code>pskCallback</code> option is now supported.</p></td></tr> 1411<tr><td>v12.9.0</td> 1412<td><p>Support the <code>allowHalfOpen</code> option.</p></td></tr> 1413<tr><td>v12.4.0</td> 1414<td><p>The <code>hints</code> option is now supported.</p></td></tr> 1415<tr><td>v12.2.0</td> 1416<td><p>The <code>enableTrace</code> option is now supported.</p></td></tr> 1417<tr><td>v11.8.0, v10.16.0</td> 1418<td><p>The <code>timeout</code> option is supported now.</p></td></tr> 1419<tr><td>v8.0.0</td> 1420<td><p>The <code>lookup</code> option is supported now.</p></td></tr> 1421<tr><td>v8.0.0</td> 1422<td><p>The <code>ALPNProtocols</code> option can be a <code>TypedArray</code> or <code>DataView</code> now.</p></td></tr> 1423<tr><td>v5.0.0</td> 1424<td><p>ALPN options are supported now.</p></td></tr> 1425<tr><td>v5.3.0, v4.7.0</td> 1426<td><p>The <code>secureContext</code> option is supported now.</p></td></tr> 1427<tr><td>v0.11.3</td> 1428<td><p><span>Added in: v0.11.3</span></p></td></tr> 1429</tbody></table> 1430</details> 1431</div> 1432<ul> 1433<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1434<ul> 1435<li><code>enableTrace</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1436<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> 1437<code>'localhost'</code>.</li> 1438<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> 1439<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 1440specified, <code>host</code> and <code>port</code> are ignored.</li> 1441<li><code>socket</code> <a href="stream.html#stream_class_stream_duplex" class="type"><stream.Duplex></a> Establish secure connection on a given socket 1442rather than creating a new socket. Typically, this is an instance of 1443<a href="net.html#net_class_net_socket"><code>net.Socket</code></a>, but any <code>Duplex</code> stream is allowed. 1444If this option is specified, <code>path</code>, <code>host</code> and <code>port</code> are ignored, 1445except for certificate validation. Usually, a socket is already connected 1446when passed to <code>tls.connect()</code>, but it can be connected later. 1447Connection/disconnection/destruction of <code>socket</code> is the user's 1448responsibility; calling <code>tls.connect()</code> will not cause <code>net.connect()</code> to be 1449called.</li> 1450<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 1451automatically end the writable side when the readable side ends. If the 1452<code>socket</code> option is set, this option has no effect. See the <code>allowHalfOpen</code> 1453option of <a href="net.html#net_class_net_socket"><code>net.Socket</code></a> for details. <strong>Default:</strong> <code>false</code>.</li> 1454<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 1455verified against the list of supplied CAs. An <code>'error'</code> event is emitted if 1456verification fails; <code>err.code</code> contains the OpenSSL error code. <strong>Default:</strong> 1457<code>true</code>.</li> 1458<li><code>pskCallback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 1459<ul> 1460<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 1461decide which identity to use during negotiation. 1462Always <code>null</code> if TLS 1.3 is used.</li> 1463<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> in the form 1464<code>{ psk: <Buffer|TypedArray|DataView>, identity: <string> }</code> 1465or <code>null</code> to stop the negotiation process. <code>psk</code> must be 1466compatible with the selected cipher's digest. 1467<code>identity</code> must use UTF-8 encoding.</li> 1468</ul> 1469When negotiating TLS-PSK (pre-shared keys), this function is called 1470with optional identity <code>hint</code> provided by the server or <code>null</code> 1471in case of TLS 1.3 where <code>hint</code> was removed. 1472It will be necessary to provide a custom <code>tls.checkServerIdentity()</code> 1473for the connection as the default one will try to check host name/IP 1474of the server against the certificate but that's not applicable for PSK 1475because there won't be a certificate present. 1476More information can be found in the <a href="https://tools.ietf.org/html/rfc4279">RFC 4279</a>.</li> 1477<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> 1478An array of strings, <code>Buffer</code>s or <code>TypedArray</code>s or <code>DataView</code>s, or a 1479single <code>Buffer</code> or <code>TypedArray</code> or <code>DataView</code> containing the supported ALPN 1480protocols. <code>Buffer</code>s should have the format <code>[len][name][len][name]...</code> 1481e.g. <code>'\x08http/1.1\x08http/1.0'</code>, where the <code>len</code> byte is the length of the 1482next protocol name. Passing an array is usually much simpler, e.g. 1483<code>['http/1.1', 'http/1.0']</code>. Protocols earlier in the list have higher 1484preference than those later.</li> 1485<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 1486extension. It is the name of the host being connected to, and must be a host 1487name, and not an IP address. It can be used by a multi-homed server to 1488choose the correct certificate to present to the client, see the 1489<code>SNICallback</code> option to <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>.</li> 1490<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 1491to be used (instead of the builtin <code>tls.checkServerIdentity()</code> function) 1492when checking the server's host name (or the provided <code>servername</code> when 1493explicitly 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 1494verification fails. The method should return <code>undefined</code> if the <code>servername</code> 1495and <code>cert</code> are verified.</li> 1496<li><code>session</code> <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> A <code>Buffer</code> instance, containing TLS session.</li> 1497<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 1498TLS connection. When a server offers a DH parameter with a size less 1499than <code>minDHSize</code>, the TLS connection is destroyed and an error is thrown. 1500<strong>Default:</strong> <code>1024</code>.</li> 1501<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. 1502<strong>Default:</strong> <code>16 * 1024</code>.</li> 1503<li><code>secureContext</code>: TLS context object created with 1504<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. If a <code>secureContext</code> is <em>not</em> provided, one 1505will be created by passing the entire <code>options</code> object to 1506<code>tls.createSecureContext()</code>.</li> 1507<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 1508stored in a single <code>buffer</code> and passed to the supplied <code>callback</code> when 1509data arrives on the socket, otherwise the option is ignored. See the 1510<code>onread</code> option of <a href="net.html#net_class_net_socket"><code>net.Socket</code></a> for details.</li> 1511<li>...: <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> options that are used if the 1512<code>secureContext</code> option is missing, otherwise they are ignored.</li> 1513<li>...: Any <a href="net.html#net_socket_connect_options_connectlistener"><code>socket.connect()</code></a> option not already listed.</li> 1514</ul> 1515</li> 1516<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1517<li>Returns: <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a></li> 1518</ul> 1519<p>The <code>callback</code> function, if specified, will be added as a listener for the 1520<a href="#tls_event_secureconnect"><code>'secureConnect'</code></a> event.</p> 1521<p><code>tls.connect()</code> returns a <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a> object.</p> 1522<p>Unlike the <code>https</code> API, <code>tls.connect()</code> does not enable the 1523SNI (Server Name Indication) extension by default, which may cause some 1524servers to return an incorrect certificate or reject the connection 1525altogether. To enable SNI, set the <code>servername</code> option in addition 1526to <code>host</code>.</p> 1527<p>The following illustrates a client for the echo server example from 1528<a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a>:</p> 1529<pre><code class="language-js"><span class="hljs-comment">// Assumes an echo server that is listening on port 8000.</span> 1530<span class="hljs-keyword">const</span> tls = <span class="hljs-built_in">require</span>(<span class="hljs-string">'tls'</span>); 1531<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 1532 1533<span class="hljs-keyword">const</span> options = { 1534 <span class="hljs-comment">// Necessary only if the server requires client certificate authentication.</span> 1535 <span class="hljs-attr">key</span>: fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'client-key.pem'</span>), 1536 <span class="hljs-attr">cert</span>: fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'client-cert.pem'</span>), 1537 1538 <span class="hljs-comment">// Necessary only if the server uses a self-signed certificate.</span> 1539 <span class="hljs-attr">ca</span>: [ fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'server-cert.pem'</span>) ], 1540 1541 <span class="hljs-comment">// Necessary only if the server's cert isn't for "localhost".</span> 1542 <span class="hljs-attr">checkServerIdentity</span>: <span class="hljs-function">() =></span> { <span class="hljs-keyword">return</span> <span class="hljs-literal">null</span>; }, 1543}; 1544 1545<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> { 1546 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'client connected'</span>, 1547 socket.<span class="hljs-property">authorized</span> ? <span class="hljs-string">'authorized'</span> : <span class="hljs-string">'unauthorized'</span>); 1548 process.<span class="hljs-property">stdin</span>.<span class="hljs-title function_">pipe</span>(socket); 1549 process.<span class="hljs-property">stdin</span>.<span class="hljs-title function_">resume</span>(); 1550}); 1551socket.<span class="hljs-title function_">setEncoding</span>(<span class="hljs-string">'utf8'</span>); 1552socket.<span class="hljs-title function_">on</span>(<span class="hljs-string">'data'</span>, <span class="hljs-function">(<span class="hljs-params">data</span>) =></span> { 1553 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(data); 1554}); 1555socket.<span class="hljs-title function_">on</span>(<span class="hljs-string">'end'</span>, <span class="hljs-function">() =></span> { 1556 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'server ends connection'</span>); 1557});</code></pre> 1558</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> 1559<div class="api_metadata"> 1560<span>Added in: v0.11.3</span> 1561</div> 1562<ul> 1563<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> 1564<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> 1565<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> 1566<li>Returns: <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a></li> 1567</ul> 1568<p>Same as <a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a> except that <code>path</code> can be provided 1569as an argument instead of an option.</p> 1570<p>A path option, if specified, will take precedence over the path argument.</p> 1571</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> 1572<div class="api_metadata"> 1573<span>Added in: v0.11.3</span> 1574</div> 1575<ul> 1576<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> 1577<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> 1578<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> 1579<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> 1580<li>Returns: <a href="tls.html#tls_class_tls_tlssocket" class="type"><tls.TLSSocket></a></li> 1581</ul> 1582<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 1583as arguments instead of options.</p> 1584<p>A port or host option, if specified, will take precedence over any port or host 1585argument.</p> 1586</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> 1587<div class="api_metadata"> 1588<details class="changelog"><summary>History</summary> 1589<table> 1590<tbody><tr><th>Version</th><th>Changes</th></tr> 1591<tr><td>v12.12.0</td> 1592<td><p>Added <code>privateKeyIdentifier</code> and <code>privateKeyEngine</code> options to get private key from an OpenSSL engine.</p></td></tr> 1593<tr><td>v12.11.0</td> 1594<td><p>Added <code>sigalgs</code> option to override supported signature algorithms.</p></td></tr> 1595<tr><td>v12.0.0</td> 1596<td><p>TLSv1.3 support added.</p></td></tr> 1597<tr><td>v11.5.0</td> 1598<td><p>The <code>ca:</code> option now supports <code>BEGIN TRUSTED CERTIFICATE</code>.</p></td></tr> 1599<tr><td>v11.4.0, v10.16.0</td> 1600<td><p>The <code>minVersion</code> and <code>maxVersion</code> can be used to restrict the allowed TLS protocol versions.</p></td></tr> 1601<tr><td>v10.0.0</td> 1602<td><p>The <code>ecdhCurve</code> cannot be set to <code>false</code> anymore due to a change in OpenSSL.</p></td></tr> 1603<tr><td>v9.3.0</td> 1604<td><p>The <code>options</code> parameter can now include <code>clientCertEngine</code>.</p></td></tr> 1605<tr><td>v9.0.0</td> 1606<td><p>The <code>ecdhCurve</code> option can now be multiple <code>':'</code> separated curve names or <code>'auto'</code>.</p></td></tr> 1607<tr><td>v7.3.0</td> 1608<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> 1609<tr><td>v5.2.0</td> 1610<td><p>The <code>ca</code> option can now be a single string containing multiple CA certificates.</p></td></tr> 1611<tr><td>v0.11.13</td> 1612<td><p><span>Added in: v0.11.13</span></p></td></tr> 1613</tbody></table> 1614</details> 1615</div> 1616<ul> 1617<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1618<ul> 1619<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 1620certificates. Default is to trust the well-known CAs curated by Mozilla. 1621Mozilla's CAs are completely replaced when CAs are explicitly specified 1622using this option. The value can be a string or <code>Buffer</code>, or an <code>Array</code> of 1623strings and/or <code>Buffer</code>s. Any string or <code>Buffer</code> can contain multiple PEM 1624CAs concatenated together. The peer's certificate must be chainable to a CA 1625trusted by the server for the connection to be authenticated. When using 1626certificates that are not chainable to a well-known CA, the certificate's CA 1627must be explicitly specified as a trusted or the connection will fail to 1628authenticate. 1629If the peer uses a certificate that doesn't match or chain to one of the 1630default CAs, use the <code>ca</code> option to provide a CA certificate that the peer's 1631certificate can match or chain to. 1632For self-signed certificates, the certificate is its own CA, and must be 1633provided. 1634For PEM encoded certificates, supported types are "TRUSTED CERTIFICATE", 1635"X509 CERTIFICATE", and "CERTIFICATE". 1636See also <a href="#tls_tls_rootcertificates"><code>tls.rootCertificates</code></a>.</li> 1637<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 1638chain should be provided per private key. Each cert chain should consist of 1639the PEM formatted certificate for a provided private <code>key</code>, followed by the 1640PEM formatted intermediate certificates (if any), in order, and not 1641including the root CA (the root CA must be pre-known to the peer, see <code>ca</code>). 1642When providing multiple cert chains, they do not have to be in the same 1643order as their private keys in <code>key</code>. If the intermediate certificates are 1644not provided, the peer will not be able to validate the certificate, and the 1645handshake will fail.</li> 1646<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. 1647The list can contain digest algorithms (<code>SHA256</code>, <code>MD5</code> etc.), public key 1648algorithms (<code>RSA-PSS</code>, <code>ECDSA</code> etc.), combination of both (e.g 1649'RSA+SHA384') or TLS v1.3 scheme names (e.g. <code>rsa_pss_pss_sha512</code>). 1650See <a href="https://www.openssl.org/docs/man1.1.1/man3/SSL_CTX_set1_sigalgs_list.html">OpenSSL man pages</a> 1651for more info.</li> 1652<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 1653more information, see <a href="#tls_modifying_the_default_tls_cipher_suite">modifying the default cipher suite</a>. Permitted 1654ciphers can be obtained via <a href="#tls_tls_getciphers"><code>tls.getCiphers()</code></a>. Cipher names must be 1655uppercased in order for OpenSSL to accept them.</li> 1656<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 1657client certificate.</li> 1658<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 1659Revocation Lists).</li> 1660<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 1661<a href="#tls_perfect_forward_secrecy">perfect forward secrecy</a>. Use <code>openssl dhparam</code> to create the parameters. 1662The key length must be greater than or equal to 1024 bits or else an error 1663will be thrown. Although 1024 bits is permissible, use 2048 bits or larger 1664for stronger security. If omitted or invalid, the parameters are silently 1665discarded and DHE ciphers will not be available.</li> 1666<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 1667list of curve NIDs or names, for example <code>P-521:P-384:P-256</code>, to use for 1668ECDH key agreement. Set to <code>auto</code> to select the 1669curve automatically. Use <a href="crypto.html#crypto_crypto_getcurves"><code>crypto.getCurves()</code></a> to obtain a list of 1670available curve names. On recent releases, <code>openssl ecparam -list_curves</code> 1671will also display the name and description of each available elliptic curve. 1672<strong>Default:</strong> <a href="#tls_tls_default_ecdh_curve"><code>tls.DEFAULT_ECDH_CURVE</code></a>.</li> 1673<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 1674preferences instead of the client's. When <code>true</code>, causes 1675<code>SSL_OP_CIPHER_SERVER_PREFERENCE</code> to be set in <code>secureOptions</code>, see 1676<a href="crypto.html#crypto_openssl_options">OpenSSL Options</a> for more information.</li> 1677<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. 1678PEM allows the option of private keys being encrypted. Encrypted keys will 1679be decrypted with <code>options.passphrase</code>. Multiple keys using different 1680algorithms can be provided either as an array of unencrypted key strings or 1681buffers, or an array of objects in the form 1682<code>{pem: <string|buffer>[, passphrase: <string>]}</code>. The object form can only 1683occur in an array. <code>object.passphrase</code> is optional. Encrypted keys will be 1684decrypted with <code>object.passphrase</code> if provided, or <code>options.passphrase</code> if 1685it is not.</li> 1686<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 1687from. Should be used together with <code>privateKeyIdentifier</code>.</li> 1688<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 1689an OpenSSL engine. Should be used together with <code>privateKeyEngine</code>. 1690Should not be set together with <code>key</code>, because both options define a 1691private key in different ways.</li> 1692<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 1693of <code>'TLSv1.3'</code>, <code>'TLSv1.2'</code>, <code>'TLSv1.1'</code>, or <code>'TLSv1'</code>. Cannot be specified 1694along with the <code>secureProtocol</code> option; use one or the other. 1695<strong>Default:</strong> <a href="#tls_tls_default_max_version"><code>tls.DEFAULT_MAX_VERSION</code></a>.</li> 1696<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 1697of <code>'TLSv1.3'</code>, <code>'TLSv1.2'</code>, <code>'TLSv1.1'</code>, or <code>'TLSv1'</code>. Cannot be specified 1698along with the <code>secureProtocol</code> option; use one or the other. Avoid 1699setting to less than TLSv1.2, but it may be required for 1700interoperability. 1701<strong>Default:</strong> <a href="#tls_tls_default_min_version"><code>tls.DEFAULT_MIN_VERSION</code></a>.</li> 1702<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 1703a PFX.</li> 1704<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 1705private key and certificate chain. <code>pfx</code> is an alternative to providing 1706<code>key</code> and <code>cert</code> individually. PFX is usually encrypted, if it is, 1707<code>passphrase</code> will be used to decrypt it. Multiple PFX can be provided either 1708as an array of unencrypted PFX buffers, or an array of objects in the form 1709<code>{buf: <string|buffer>[, passphrase: <string>]}</code>. The object form can only 1710occur in an array. <code>object.passphrase</code> is optional. Encrypted PFX will be 1711decrypted with <code>object.passphrase</code> if provided, or <code>options.passphrase</code> if 1712it is not.</li> 1713<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, 1714which is not usually necessary. This should be used carefully if at all! 1715Value is a numeric bitmask of the <code>SSL_OP_*</code> options from 1716<a href="crypto.html#crypto_openssl_options">OpenSSL Options</a>.</li> 1717<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 1718version to use, it does not support independent control of the minimum and 1719maximum version, and does not support limiting the protocol to TLSv1.3. Use 1720<code>minVersion</code> and <code>maxVersion</code> instead. The possible values are listed as 1721<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 1722<code>'TLSv1_1_method'</code> to force TLS version 1.1, or <code>'TLS_method'</code> to allow any 1723TLS protocol version up to TLSv1.3. It is not recommended to use TLS 1724versions less than 1.2, but it may be required for interoperability. 1725<strong>Default:</strong> none, see <code>minVersion</code>.</li> 1726<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 1727session state is not shared between applications. Unused by clients.</li> 1728<li><code>ticketKeys</code>: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> 48-bytes of cryptographically strong pseudo-random 1729data. See <a href="#tls_session_resumption">Session Resumption</a> for more information.</li> 1730<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 1731created by the server will no longer be resumable. See 1732<a href="#tls_session_resumption">Session Resumption</a> for more information. <strong>Default:</strong> <code>300</code>.</li> 1733</ul> 1734</li> 1735</ul> 1736<p><a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a> sets the default value of the <code>honorCipherOrder</code> option 1737to <code>true</code>, other APIs that create secure contexts leave it unset.</p> 1738<p><a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a> uses a 128 bit truncated SHA1 hash value generated 1739from <code>process.argv</code> as the default value of the <code>sessionIdContext</code> option, other 1740APIs that create secure contexts have no default value.</p> 1741<p>The <code>tls.createSecureContext()</code> method creates a <code>SecureContext</code> object. It is 1742usable as an argument to several <code>tls</code> APIs, such as <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a> 1743and <a href="#tls_server_addcontext_hostname_context"><code>server.addContext()</code></a>, but has no public methods.</p> 1744<p>A key is <em>required</em> for ciphers that use certificates. Either <code>key</code> or 1745<code>pfx</code> can be used to provide it.</p> 1746<p>If the <code>ca</code> option is not given, then Node.js will default to using 1747<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> 1748</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> 1749<div class="api_metadata"> 1750<details class="changelog"><summary>History</summary> 1751<table> 1752<tbody><tr><th>Version</th><th>Changes</th></tr> 1753<tr><td>v5.0.0</td> 1754<td><p>ALPN options are supported now.</p></td></tr> 1755<tr><td>v0.11.3</td> 1756<td><p><span>Deprecated since: v0.11.3</span></p></td></tr> 1757<tr><td>v0.3.2</td> 1758<td><p><span>Added in: v0.3.2</span></p></td></tr> 1759</tbody></table> 1760</details> 1761</div> 1762<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> 1763<ul> 1764<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 1765<code>tls.createSecureContext()</code></li> 1766<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 1767opened as a server.</li> 1768<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 1769certificate from a connecting client. Only applies when <code>isServer</code> is <code>true</code>.</li> 1770<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 1771clients with invalid certificates. Only applies when <code>isServer</code> is <code>true</code>.</li> 1772<li><code>options</code> 1773<ul> 1774<li><code>enableTrace</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1775<li><code>secureContext</code>: A TLS context object from <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a></li> 1776<li><code>isServer</code>: If <code>true</code> the TLS socket will be instantiated in server-mode. 1777<strong>Default:</strong> <code>false</code>.</li> 1778<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> 1779<li><code>requestCert</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1780<li><code>rejectUnauthorized</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1781<li><code>ALPNProtocols</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1782<li><code>SNICallback</code>: See <a href="#tls_tls_createserver_options_secureconnectionlistener"><code>tls.createServer()</code></a></li> 1783<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> 1784<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 1785extension will be added to the client hello and an <code>'OCSPResponse'</code> event 1786will be emitted on the socket before establishing a secure communication.</li> 1787</ul> 1788</li> 1789</ul> 1790<p>Creates a new secure pair object with two streams, one of which reads and writes 1791the encrypted data and the other of which reads and writes the cleartext data. 1792Generally, the encrypted stream is piped to/from an incoming encrypted data 1793stream and the cleartext one is used as a replacement for the initial encrypted 1794stream.</p> 1795<p><code>tls.createSecurePair()</code> returns a <code>tls.SecurePair</code> object with <code>cleartext</code> and 1796<code>encrypted</code> stream properties.</p> 1797<p>Using <code>cleartext</code> has the same API as <a href="#tls_class_tls_tlssocket"><code>tls.TLSSocket</code></a>.</p> 1798<p>The <code>tls.createSecurePair()</code> method is now deprecated in favor of 1799<code>tls.TLSSocket()</code>. For example, the code:</p> 1800<pre><code class="language-js">pair = tls.<span class="hljs-title function_">createSecurePair</span>(<span class="hljs-comment">/* ... */</span>); 1801pair.<span class="hljs-property">encrypted</span>.<span class="hljs-title function_">pipe</span>(socket); 1802socket.<span class="hljs-title function_">pipe</span>(pair.<span class="hljs-property">encrypted</span>);</code></pre> 1803<p>can be replaced by:</p> 1804<pre><code class="language-js">secureSocket = tls.<span class="hljs-title function_">TLSSocket</span>(socket, options);</code></pre> 1805<p>where <code>secureSocket</code> has the same API as <code>pair.cleartext</code>.</p> 1806</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> 1807<div class="api_metadata"> 1808<details class="changelog"><summary>History</summary> 1809<table> 1810<tbody><tr><th>Version</th><th>Changes</th></tr> 1811<tr><td>v12.3.0</td> 1812<td><p>The <code>options</code> parameter now supports <code>net.createServer()</code> options.</p></td></tr> 1813<tr><td>v9.3.0</td> 1814<td><p>The <code>options</code> parameter can now include <code>clientCertEngine</code>.</p></td></tr> 1815<tr><td>v8.0.0</td> 1816<td><p>The <code>ALPNProtocols</code> option can be a <code>TypedArray</code> or <code>DataView</code> now.</p></td></tr> 1817<tr><td>v5.0.0</td> 1818<td><p>ALPN options are supported now.</p></td></tr> 1819<tr><td>v0.3.2</td> 1820<td><p><span>Added in: v0.3.2</span></p></td></tr> 1821</tbody></table> 1822</details> 1823</div> 1824<ul> 1825<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1826<ul> 1827<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> 1828An array of strings, <code>Buffer</code>s or <code>TypedArray</code>s or <code>DataView</code>s, or a single 1829<code>Buffer</code> or <code>TypedArray</code> or <code>DataView</code> containing the supported ALPN 1830protocols. <code>Buffer</code>s should have the format <code>[len][name][len][name]...</code> 1831e.g. <code>0x05hello0x05world</code>, where the first byte is the length of the next 1832protocol name. Passing an array is usually much simpler, e.g. 1833<code>['hello', 'world']</code>. (Protocols should be ordered by their priority.)</li> 1834<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 1835client certificate.</li> 1836<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 1837called on new connections. Tracing can be enabled after the secure 1838connection is established, but this option must be used to trace the secure 1839connection setup. <strong>Default:</strong> <code>false</code>.</li> 1840<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 1841does not finish in the specified number of milliseconds. 1842A <code>'tlsClientError'</code> is emitted on the <code>tls.Server</code> object whenever 1843a handshake times out. <strong>Default:</strong> <code>120000</code> (120 seconds).</li> 1844<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 1845connection which is not authorized with the list of supplied CAs. This 1846option only has an effect if <code>requestCert</code> is <code>true</code>. <strong>Default:</strong> <code>true</code>.</li> 1847<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 1848clients that connect and attempt to verify that certificate. <strong>Default:</strong> 1849<code>false</code>.</li> 1850<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 1851created by the server will no longer be resumable. See 1852<a href="#tls_session_resumption">Session Resumption</a> for more information. <strong>Default:</strong> <code>300</code>.</li> 1853<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 1854called if the client supports SNI TLS extension. Two arguments will be 1855passed when called: <code>servername</code> and <code>callback</code>. <code>callback</code> is an 1856error-first callback that takes two optional arguments: <code>error</code> and <code>ctx</code>. 1857<code>ctx</code>, if provided, is a <code>SecureContext</code> instance. 1858<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> can be used to get a proper <code>SecureContext</code>. 1859If <code>callback</code> is called with a falsy <code>ctx</code> argument, the default secure 1860context of the server will be used. If <code>SNICallback</code> wasn't provided the 1861default callback with high-level API will be used (see below).</li> 1862<li><code>ticketKeys</code>: <a href="buffer.html#buffer_class_buffer" class="type"><Buffer></a> 48-bytes of cryptographically strong pseudo-random 1863data. See <a href="#tls_session_resumption">Session Resumption</a> for more information.</li> 1864<li><code>pskCallback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> 1865<ul> 1866<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 1867this connection.</li> 1868<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> 1869<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 1870a buffer or <code>null</code> to stop the negotiation process. Returned PSK must be 1871compatible with the selected cipher's digest.</li> 1872</ul> 1873When negotiating TLS-PSK (pre-shared keys), this function is called 1874with the identity provided by the client. 1875If the return value is <code>null</code> the negotiation process will stop and an 1876"unknown_psk_identity" alert message will be sent to the other party. 1877If the server wishes to hide the fact that the PSK identity was not known, 1878the callback must provide some random data as <code>psk</code> to make the connection 1879fail with "decrypt_error" before negotiation is finished. 1880PSK ciphers are disabled by default, and using TLS-PSK thus 1881requires explicitly specifying a cipher suite with the <code>ciphers</code> option. 1882More information can be found in the <a href="https://tools.ietf.org/html/rfc4279">RFC 4279</a>.</li> 1883<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 1884with selecting the identity during TLS-PSK negotiation. Will be ignored 1885in TLS 1.3. Upon failing to set pskIdentityHint <code>'tlsClientError'</code> will be 1886emitted with <code>'ERR_TLS_PSK_SET_IDENTIY_HINT_FAILED'</code> code.</li> 1887<li>...: Any <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> option can be provided. For 1888servers, the identity options (<code>pfx</code>, <code>key</code>/<code>cert</code> or <code>pskCallback</code>) 1889are usually required.</li> 1890<li>...: Any <a href="net.html#net_net_createserver_options_connectionlistener"><code>net.createServer()</code></a> option can be provided.</li> 1891</ul> 1892</li> 1893<li><code>secureConnectionListener</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a></li> 1894<li>Returns: <a href="tls.html#tls_class_tls_server" class="type"><tls.Server></a></li> 1895</ul> 1896<p>Creates a new <a href="#tls_class_tls_server"><code>tls.Server</code></a>. The <code>secureConnectionListener</code>, if provided, is 1897automatically set as a listener for the <a href="#tls_event_secureconnection"><code>'secureConnection'</code></a> event.</p> 1898<p>The <code>ticketKeys</code> options is automatically shared between <code>cluster</code> module 1899workers.</p> 1900<p>The following illustrates a simple echo server:</p> 1901<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>); 1902<span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 1903 1904<span class="hljs-keyword">const</span> options = { 1905 <span class="hljs-attr">key</span>: fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'server-key.pem'</span>), 1906 <span class="hljs-attr">cert</span>: fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'server-cert.pem'</span>), 1907 1908 <span class="hljs-comment">// This is necessary only if using client certificate authentication.</span> 1909 <span class="hljs-attr">requestCert</span>: <span class="hljs-literal">true</span>, 1910 1911 <span class="hljs-comment">// This is necessary only if the client uses a self-signed certificate.</span> 1912 <span class="hljs-attr">ca</span>: [ fs.<span class="hljs-title function_">readFileSync</span>(<span class="hljs-string">'client-cert.pem'</span>) ] 1913}; 1914 1915<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> { 1916 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'server connected'</span>, 1917 socket.<span class="hljs-property">authorized</span> ? <span class="hljs-string">'authorized'</span> : <span class="hljs-string">'unauthorized'</span>); 1918 socket.<span class="hljs-title function_">write</span>(<span class="hljs-string">'welcome!\n'</span>); 1919 socket.<span class="hljs-title function_">setEncoding</span>(<span class="hljs-string">'utf8'</span>); 1920 socket.<span class="hljs-title function_">pipe</span>(socket); 1921}); 1922server.<span class="hljs-title function_">listen</span>(<span class="hljs-number">8000</span>, <span class="hljs-function">() =></span> { 1923 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'server bound'</span>); 1924});</code></pre> 1925<p>The server can be tested by connecting to it using the example client from 1926<a href="#tls_tls_connect_options_callback"><code>tls.connect()</code></a>.</p> 1927</section><section><h3><code>tls.getCiphers()</code><span><a class="mark" href="#tls_tls_getciphers" id="tls_tls_getciphers">#</a></span></h3> 1928<div class="api_metadata"> 1929<span>Added in: v0.10.2</span> 1930</div> 1931<ul> 1932<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 1933</ul> 1934<p>Returns an array with the names of the supported TLS ciphers. The names are 1935lower-case for historical reasons, but must be uppercased to be used in 1936the <code>ciphers</code> option of <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>.</p> 1937<p>Cipher names that start with <code>'tls_'</code> are for TLSv1.3, all the others are for 1938TLSv1.2 and below.</p> 1939<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> 1940</section><section><h3><code>tls.rootCertificates</code><span><a class="mark" href="#tls_tls_rootcertificates" id="tls_tls_rootcertificates">#</a></span></h3> 1941<div class="api_metadata"> 1942<span>Added in: v12.3.0</span> 1943</div> 1944<ul> 1945<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 1946</ul> 1947<p>An immutable array of strings representing the root certificates (in PEM format) 1948from the bundled Mozilla CA store as supplied by current Node.js version.</p> 1949<p>The bundled CA store, as supplied by Node.js, is a snapshot of Mozilla CA store 1950that is fixed at release time. It is identical on all supported platforms.</p> 1951</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> 1952<div class="api_metadata"> 1953<details class="changelog"><summary>History</summary> 1954<table> 1955<tbody><tr><th>Version</th><th>Changes</th></tr> 1956<tr><td>v10.0.0</td> 1957<td><p>Default value changed to <code>'auto'</code>.</p></td></tr> 1958<tr><td>v0.11.13</td> 1959<td><p><span>Added in: v0.11.13</span></p></td></tr> 1960</tbody></table> 1961</details> 1962</div> 1963<p>The default curve name to use for ECDH key agreement in a tls server. The 1964default value is <code>'auto'</code>. See <a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a> for further 1965information.</p> 1966</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> 1967<div class="api_metadata"> 1968<span>Added in: v11.4.0</span> 1969</div> 1970<ul> 1971<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 1972<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. It can be assigned any of the supported TLS 1973protocol versions, <code>'TLSv1.3'</code>, <code>'TLSv1.2'</code>, <code>'TLSv1.1'</code>, or <code>'TLSv1'</code>. 1974<strong>Default:</strong> <code>'TLSv1.3'</code>, unless changed using CLI options. Using 1975<code>--tls-max-v1.2</code> sets the default to <code>'TLSv1.2'</code>. Using <code>--tls-max-v1.3</code> sets 1976the default to <code>'TLSv1.3'</code>. If multiple of the options are provided, the 1977highest maximum is used.</li> 1978</ul> 1979</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> 1980<div class="api_metadata"> 1981<span>Added in: v11.4.0</span> 1982</div> 1983<ul> 1984<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 1985<a href="#tls_tls_createsecurecontext_options"><code>tls.createSecureContext()</code></a>. It can be assigned any of the supported TLS 1986protocol versions, <code>'TLSv1.3'</code>, <code>'TLSv1.2'</code>, <code>'TLSv1.1'</code>, or <code>'TLSv1'</code>. 1987<strong>Default:</strong> <code>'TLSv1.2'</code>, unless changed using CLI options. Using 1988<code>--tls-min-v1.0</code> sets the default to <code>'TLSv1'</code>. Using <code>--tls-min-v1.1</code> sets 1989the default to <code>'TLSv1.1'</code>. Using <code>--tls-min-v1.3</code> sets the default to 1990<code>'TLSv1.3'</code>. If multiple of the options are provided, the lowest minimum is 1991used.</li> 1992</ul></section> 1993 <!-- API END --> 1994 </div> 1995 </div> 1996 </div> 1997 <script> 1998 'use strict'; 1999 { 2000 const kCustomPreference = 'customDarkTheme'; 2001 const userSettings = sessionStorage.getItem(kCustomPreference); 2002 const themeToggleButton = document.getElementById('theme-toggle-btn'); 2003 if (userSettings === null && window.matchMedia) { 2004 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 2005 if ('onchange' in mq) { 2006 function mqChangeListener(e) { 2007 document.body.classList.toggle('dark-mode', e.matches); 2008 } 2009 mq.addEventListener('change', mqChangeListener); 2010 if (themeToggleButton) { 2011 themeToggleButton.addEventListener('click', function() { 2012 mq.removeEventListener('change', mqChangeListener); 2013 }, { once: true }); 2014 } 2015 } 2016 if (mq.matches) { 2017 document.body.classList.add('dark-mode'); 2018 } 2019 } else if (userSettings === 'true') { 2020 document.body.classList.add('dark-mode'); 2021 } 2022 if (themeToggleButton) { 2023 themeToggleButton.hidden = false; 2024 themeToggleButton.addEventListener('click', function() { 2025 sessionStorage.setItem( 2026 kCustomPreference, 2027 document.body.classList.toggle('dark-mode') 2028 ); 2029 }); 2030 } 2031 } 2032 </script> 2033</body> 2034</html> 2035