tls: support changing credentials dynamically

This commit adds a setSecureContext() method to TLS servers. In
order to maintain backwards compatibility, the method takes the
options needed to create a new SecureContext, rather than an
instance of SecureContext.

Fixes: https://github.com/nodejs/node/issues/4464
Refs: https://github.com/nodejs/node/issues/10349
Refs: https://github.com/nodejs/help/issues/603
Refs: https://github.com/nodejs/node/issues/15115
PR-URL: https://github.com/nodejs/node/pull/23644
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

doc/api/tls.md

@@ -411,6 +411,18 @@ encryption/decryption of the [TLS Session Tickets][].
 Starts the server listening for encrypted connections.
 This method is identical to [`server.listen()`][] from [`net.Server`][].
 
+### server.setSecureContext(options)
+<!-- YAML
+added: REPLACEME
+-->
+
+* `options` {Object} An object containing any of the possible properties from
+  the [`tls.createSecureContext()`][] `options` arguments (e.g. `key`, `cert`,
+  `ca`, etc).
+
+The `server.setSecureContext()` method replaces the secure context of an
+existing server. Existing connections to the server are not interrupted.
+
 ### server.setTicketKeys(keys)
 <!-- YAML
 added: v3.0.0

lib/_tls_wrap.js

@@ -833,6 +833,120 @@ function Server(options, listener) {
   // Handle option defaults:
   this.setOptions(options);
 
+  // setSecureContext() overlaps with setOptions() quite a bit. setOptions()
+  // is an undocumented API that was probably never intended to be exposed
+  // publicly. Unfortunately, it would be a breaking change to just remove it,
+  // and there is at least one test that depends on it.
+  this.setSecureContext(options);
+
+  this[kHandshakeTimeout] = options.handshakeTimeout || (120 * 1000);
+  this[kSNICallback] = options.SNICallback;
+
+  if (typeof this[kHandshakeTimeout] !== 'number') {
+    throw new ERR_INVALID_ARG_TYPE(
+      'options.handshakeTimeout', 'number', options.handshakeTimeout);
+  }
+
+  if (this[kSNICallback] && typeof this[kSNICallback] !== 'function') {
+    throw new ERR_INVALID_ARG_TYPE(
+      'options.SNICallback', 'function', options.SNICallback);
+  }
+
+  // constructor call
+  net.Server.call(this, tlsConnectionListener);
+
+  if (listener) {
+    this.on('secureConnection', listener);
+  }
+}
+
+util.inherits(Server, net.Server);
+exports.Server = Server;
+exports.createServer = function createServer(options, listener) {
+  return new Server(options, listener);
+};
+
+
+Server.prototype.setSecureContext = function(options) {
+  if (options === null || typeof options !== 'object')
+    throw new ERR_INVALID_ARG_TYPE('options', 'Object', options);
+
+  if (options.pfx)
+    this.pfx = options.pfx;
+  else
+    this.pfx = undefined;
+
+  if (options.key)
+    this.key = options.key;
+  else
+    this.key = undefined;
+
+  if (options.passphrase)
+    this.passphrase = options.passphrase;
+  else
+    this.passphrase = undefined;
+
+  if (options.cert)
+    this.cert = options.cert;
+  else
+    this.cert = undefined;
+
+  if (options.clientCertEngine)
+    this.clientCertEngine = options.clientCertEngine;
+  else
+    this.clientCertEngine = undefined;
+
+  if (options.ca)
+    this.ca = options.ca;
+  else
+    this.ca = undefined;
+
+  if (options.secureProtocol)
+    this.secureProtocol = options.secureProtocol;
+  else
+    this.secureProtocol = undefined;
+
+  if (options.crl)
+    this.crl = options.crl;
+  else
+    this.crl = undefined;
+
+  if (options.ciphers)
+    this.ciphers = options.ciphers;
+  else
+    this.ciphers = undefined;
+
+  if (options.ecdhCurve !== undefined)
+    this.ecdhCurve = options.ecdhCurve;
+  else
+    this.ecdhCurve = undefined;
+
+  if (options.dhparam)
+    this.dhparam = options.dhparam;
+  else
+    this.dhparam = undefined;
+
+  if (options.honorCipherOrder !== undefined)
+    this.honorCipherOrder = !!options.honorCipherOrder;
+  else
+    this.honorCipherOrder = true;
+
+  const secureOptions = options.secureOptions || 0;
+
+  if (secureOptions)
+    this.secureOptions = secureOptions;
+  else
+    this.secureOptions = undefined;
+
+  if (options.sessionIdContext) {
+    this.sessionIdContext = options.sessionIdContext;
+  } else {
+    this.sessionIdContext = crypto.createHash('sha1')
+                                  .update(process.argv.join(' '))
+                                  .digest('hex')
+                                  .slice(0, 32);
+  }
+
   this._sharedCreds = tls.createSecureContext({
     pfx: this.pfx,
     key: this.key,
@@ -850,39 +964,15 @@ function Server(options, listener) {
     sessionIdContext: this.sessionIdContext
   });
 
-  this[kHandshakeTimeout] = options.handshakeTimeout || (120 * 1000);
+  if (this.sessionTimeout)
-  this[kSNICallback] = options.SNICallback;
-
-  if (typeof this[kHandshakeTimeout] !== 'number') {
-    throw new ERR_INVALID_ARG_TYPE(
-      'options.handshakeTimeout', 'number', options.handshakeTimeout);
-  }
-
-  if (this[kSNICallback] && typeof this[kSNICallback] !== 'function') {
-    throw new ERR_INVALID_ARG_TYPE(
-      'options.SNICallback', 'function', options.SNICallback);
-  }
-
-  if (this.sessionTimeout) {
     this._sharedCreds.context.setSessionTimeout(this.sessionTimeout);
+
+  if (options.ticketKeys) {
+    this.ticketKeys = options.ticketKeys;
+    this.setTicketKeys(this.ticketKeys);
+  } else {
+    this.setTicketKeys(this.getTicketKeys());
   }
-
-  if (this.ticketKeys) {
-    this._sharedCreds.context.setTicketKeys(this.ticketKeys);
-  }
-
-  // constructor call
-  net.Server.call(this, tlsConnectionListener);
-
-  if (listener) {
-    this.on('secureConnection', listener);
-  }
-}
-
-util.inherits(Server, net.Server);
-exports.Server = Server;
-exports.createServer = function createServer(options, listener) {
-  return new Server(options, listener);
 };
 
 

test/parallel/test-tls-set-secure-context.js

@@ -0,0 +1,88 @@
+'use strict';
+const common = require('../common');
+
+if (!common.hasCrypto)
+  common.skip('missing crypto');
+
+const assert = require('assert');
+const https = require('https');
+const fixtures = require('../common/fixtures');
+const credentialOptions = [
+  {
+    key: fixtures.readKey('agent1-key.pem'),
+    cert: fixtures.readKey('agent1-cert.pem'),
+    ca: fixtures.readKey('ca1-cert.pem')
+  },
+  {
+    key: fixtures.readKey('agent2-key.pem'),
+    cert: fixtures.readKey('agent2-cert.pem'),
+    ca: fixtures.readKey('ca2-cert.pem')
+  }
+];
+let requestsCount = 0;
+let firstResponse;
+
+const server = https.createServer(credentialOptions[0], (req, res) => {
+  requestsCount++;
+
+  if (requestsCount === 1) {
+    firstResponse = res;
+    firstResponse.write('multi-');
+    return;
+  } else if (requestsCount === 3) {
+    firstResponse.write('success-');
+  }
+
+  res.end('success');
+});
+
+server.listen(0, common.mustCall(async () => {
+  const { port } = server.address();
+  const firstRequest = makeRequest(port);
+
+  assert.strictEqual(await makeRequest(port), 'success');
+
+  server.setSecureContext(credentialOptions[1]);
+  firstResponse.write('request-');
+  await assert.rejects(async () => {
+    await makeRequest(port);
+  }, /^Error: self signed certificate$/);
+
+  server.setSecureContext(credentialOptions[0]);
+  assert.strictEqual(await makeRequest(port), 'success');
+
+  server.setSecureContext(credentialOptions[1]);
+  firstResponse.end('fun!');
+  await assert.rejects(async () => {
+    await makeRequest(port);
+  }, /^Error: self signed certificate$/);
+
+  assert.strictEqual(await firstRequest, 'multi-request-success-fun!');
+  server.close();
+}));
+
+function makeRequest(port) {
+  return new Promise((resolve, reject) => {
+    const options = {
+      rejectUnauthorized: true,
+      ca: credentialOptions[0].ca,
+      servername: 'agent1'
+    };
+
+    https.get(`https://localhost:${port}`, options, (res) => {
+      let response = '';
+
+      res.setEncoding('utf8');
+
+      res.on('data', (chunk) => {
+        response += chunk;
+      });
+
+      res.on('end', common.mustCall(() => {
+        resolve(response);
+      }));
+    }).on('error', (err) => {
+      reject(err);
+    });
+  });
+}