[Mailer][Smtp] Add DSN param peer_fingerprint for fingerprint verification

Author: xdavidwu

CHANGELOG.md

@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+6.4
+---
+
+ * Add DSN parameter `peer_fingerprint` to verify TLS certificate fingerprint
+
 6.3
 ---
 

Tests/Transport/Smtp/EsmtpTransportFactoryTest.php

@@ -109,6 +109,23 @@ public static function createProvider(): iterable
             $transport,
         ];
 
+        $transport = new EsmtpTransport('example.com', 465, true, null, $logger);
+        /** @var SocketStream $stream */
+        $stream = $transport->getStream();
+        $streamOptions = $stream->getStreamOptions();
+        $streamOptions['ssl']['peer_fingerprint'] = '6A1CF3B08D175A284C30BC10DE19162307C7286E';
+        $stream->setStreamOptions($streamOptions);
+
+        yield [
+            new Dsn('smtps', 'example.com', '', '', 465, ['peer_fingerprint' => '6A1CF3B08D175A284C30BC10DE19162307C7286E']),
+            $transport,
+        ];
+
+        yield [
+            Dsn::fromString('smtps://:@example.com?peer_fingerprint=6A1CF3B08D175A284C30BC10DE19162307C7286E'),
+            $transport,
+        ];
+
         $transport = new EsmtpTransport('example.com', 465, true, null, $logger);
         $transport->setLocalDomain('example.com');
 

Transport/Smtp/EsmtpTransportFactory.php

@@ -29,17 +29,21 @@ public function create(Dsn $dsn): TransportInterface
 
         $transport = new EsmtpTransport($host, $port, $tls, $this->dispatcher, $this->logger);
 
-        if ('' !== $dsn->getOption('verify_peer') && !filter_var($dsn->getOption('verify_peer', true), \FILTER_VALIDATE_BOOL)) {
-            /** @var SocketStream $stream */
-            $stream = $transport->getStream();
-            $streamOptions = $stream->getStreamOptions();
+        /** @var SocketStream $stream */
+        $stream = $transport->getStream();
+        $streamOptions = $stream->getStreamOptions();
 
+        if ('' !== $dsn->getOption('verify_peer') && !filter_var($dsn->getOption('verify_peer', true), \FILTER_VALIDATE_BOOL)) {
             $streamOptions['ssl']['verify_peer'] = false;
             $streamOptions['ssl']['verify_peer_name'] = false;
+        }
 
-            $stream->setStreamOptions($streamOptions);
+        if (null !== $peerFingerprint = $dsn->getOption('peer_fingerprint')) {
+            $streamOptions['ssl']['peer_fingerprint'] = $peerFingerprint;
         }
 
+        $stream->setStreamOptions($streamOptions);
+
         if ($user = $dsn->getUser()) {
             $transport->setUsername($user);
         }