Upgrade PHPMailer to 6.3.0 (#3457)

* Upgrade PHPMailer to 6.2.0

* Bump PHPMailer to 6.3.0

Co-authored-by: berumuron <dev@marienfressinaud.fr>

lib/PHPMailer/PHPMailer/Exception.php

@@ -1,4 +1,5 @@
 <?php
+
 /**
  * PHPMailer Exception class.
  * PHP Version 5.5.
@@ -9,7 +10,7 @@
  * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
  * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
  * @author    Brent R. Matzelle (original founder)
- * @copyright 2012 - 2017 Marcus Bointon
+ * @copyright 2012 - 2020 Marcus Bointon
  * @copyright 2010 - 2012 Jim Jagielski
  * @copyright 2004 - 2009 Andy Prevost
  * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License

lib/PHPMailer/PHPMailer/SMTP.php

@@ -1,4 +1,5 @@
 <?php
+
 /**
  * PHPMailer RFC821 SMTP email transport class.
  * PHP Version 5.5.
@@ -9,7 +10,7 @@
  * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
  * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
  * @author    Brent R. Matzelle (original founder)
- * @copyright 2012 - 2019 Marcus Bointon
+ * @copyright 2012 - 2020 Marcus Bointon
  * @copyright 2010 - 2012 Jim Jagielski
  * @copyright 2004 - 2009 Andy Prevost
  * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
@@ -34,7 +35,7 @@ class SMTP
      *
      * @var string
      */
-    const VERSION = '6.1.6';
+    const VERSION = '6.3.0';
 
     /**
      * SMTP line break constant.
@@ -311,17 +312,11 @@ class SMTP
      */
     public function connect($host, $port = null, $timeout = 30, $options = [])
     {
-        static $streamok;
-        //This is enabled by default since 5.0.0 but some providers disable it
-        //Check this once and cache the result
-        if (null === $streamok) {
-            $streamok = function_exists('stream_socket_client');
-        }
-        // Clear errors to avoid confusion
+        //Clear errors to avoid confusion
         $this->setError('');
-        // Make sure we are __not__ connected
+        //Make sure we are __not__ connected
         if ($this->connected()) {
-            // Already connected, generate error
+            //Already connected, generate error
             $this->setError('Already connected to a server');
 
             return false;
@@ -329,18 +324,66 @@ class SMTP
         if (empty($port)) {
             $port = self::DEFAULT_PORT;
         }
-        // Connect to the SMTP server
+        //Connect to the SMTP server
         $this->edebug(
             "Connection: opening to $host:$port, timeout=$timeout, options=" .
             (count($options) > 0 ? var_export($options, true) : 'array()'),
             self::DEBUG_CONNECTION
         );
+
+        $this->smtp_conn = $this->getSMTPConnection($host, $port, $timeout, $options);
+
+        if ($this->smtp_conn === false) {
+            //Error info already set inside `getSMTPConnection()`
+            return false;
+        }
+
+        $this->edebug('Connection: opened', self::DEBUG_CONNECTION);
+
+        //Get any announcement
+        $this->last_reply = $this->get_lines();
+        $this->edebug('SERVER -> CLIENT: ' . $this->last_reply, self::DEBUG_SERVER);
+        $responseCode = (int)substr($this->last_reply, 0, 3);
+        if ($responseCode === 220) {
+            return true;
+        }
+        //Anything other than a 220 response means something went wrong
+        //RFC 5321 says the server will wait for us to send a QUIT in response to a 554 error
+        //https://tools.ietf.org/html/rfc5321#section-3.1
+        if ($responseCode === 554) {
+            $this->quit();
+        }
+        //This will handle 421 responses which may not wait for a QUIT (e.g. if the server is being shut down)
+        $this->edebug('Connection: closing due to error', self::DEBUG_CONNECTION);
+        $this->close();
+        return false;
+    }
+
+    /**
+     * Create connection to the SMTP server.
+     *
+     * @param string $host    SMTP server IP or host name
+     * @param int    $port    The port number to connect to
+     * @param int    $timeout How long to wait for the connection to open
+     * @param array  $options An array of options for stream_context_create()
+     *
+     * @return false|resource
+     */
+    protected function getSMTPConnection($host, $port = null, $timeout = 30, $options = [])
+    {
+        static $streamok;
+        //This is enabled by default since 5.0.0 but some providers disable it
+        //Check this once and cache the result
+        if (null === $streamok) {
+            $streamok = function_exists('stream_socket_client');
+        }
+
         $errno = 0;
         $errstr = '';
         if ($streamok) {
             $socket_context = stream_context_create($options);
             set_error_handler([$this, 'errorHandler']);
-            $this->smtp_conn = stream_socket_client(
+            $connection = stream_socket_client(
                 $host . ':' . $port,
                 $errno,
                 $errstr,
@@ -356,7 +399,7 @@ class SMTP
                 self::DEBUG_CONNECTION
             );
             set_error_handler([$this, 'errorHandler']);
-            $this->smtp_conn = fsockopen(
+            $connection = fsockopen(
                 $host,
                 $port,
                 $errno,
@@ -365,8 +408,9 @@ class SMTP
             );
             restore_error_handler();
         }
-        // Verify we connected properly
-        if (!is_resource($this->smtp_conn)) {
+
+        //Verify we connected properly
+        if (!is_resource($connection)) {
             $this->setError(
                 'Failed to connect to server',
                 '',
@@ -381,22 +425,19 @@ class SMTP
 
             return false;
         }
-        $this->edebug('Connection: opened', self::DEBUG_CONNECTION);
-        // SMTP server can take longer to respond, give longer timeout for first read
-        // Windows does not have support for this timeout function
+
+        //SMTP server can take longer to respond, give longer timeout for first read
+        //Windows does not have support for this timeout function
         if (strpos(PHP_OS, 'WIN') !== 0) {
-            $max = (int) ini_get('max_execution_time');
-            // Don't bother if unlimited
-            if (0 !== $max && $timeout > $max) {
+            $max = (int)ini_get('max_execution_time');
+            //Don't bother if unlimited, or if set_time_limit is disabled
+            if (0 !== $max && $timeout > $max && strpos(ini_get('disable_functions'), 'set_time_limit') === false) {
                 @set_time_limit($timeout);
             }
-            stream_set_timeout($this->smtp_conn, $timeout, 0);
+            stream_set_timeout($connection, $timeout, 0);
         }
-        // Get any announcement
-        $announce = $this->get_lines();
-        $this->edebug('SERVER -> CLIENT: ' . $announce, self::DEBUG_SERVER);
 
-        return true;
+        return $connection;
     }
 
     /**
@@ -420,7 +461,7 @@ class SMTP
             $crypto_method |= STREAM_CRYPTO_METHOD_TLSv1_1_CLIENT;
         }
 
-        // Begin encrypted connection
+        //Begin encrypted connection
         set_error_handler([$this, 'errorHandler']);
         $crypto_ok = stream_socket_enable_crypto(
             $this->smtp_conn,
@@ -458,11 +499,11 @@ class SMTP
         }
 
         if (array_key_exists('EHLO', $this->server_caps)) {
-            // SMTP extensions are available; try to find a proper authentication method
+            //SMTP extensions are available; try to find a proper authentication method
             if (!array_key_exists('AUTH', $this->server_caps)) {
                 $this->setError('Authentication is not allowed at this stage');
-                // 'at this stage' means that auth may be allowed after the stage changes
-                // e.g. after STARTTLS
+                //'at this stage' means that auth may be allowed after the stage changes
+                //e.g. after STARTTLS
 
                 return false;
             }
@@ -506,22 +547,23 @@ class SMTP
         }
         switch ($authtype) {
             case 'PLAIN':
-                // Start authentication
+                //Start authentication
                 if (!$this->sendCommand('AUTH', 'AUTH PLAIN', 334)) {
                     return false;
                 }
-                // Send encoded username and password
-                if (!$this->sendCommand(
-                    'User & Password',
-                    base64_encode("\0" . $username . "\0" . $password),
-                    235
-                )
+                //Send encoded username and password
+                if (
+                    !$this->sendCommand(
+                        'User & Password',
+                        base64_encode("\0" . $username . "\0" . $password),
+                        235
+                    )
                 ) {
                     return false;
                 }
                 break;
             case 'LOGIN':
-                // Start authentication
+                //Start authentication
                 if (!$this->sendCommand('AUTH', 'AUTH LOGIN', 334)) {
                     return false;
                 }
@@ -533,17 +575,17 @@ class SMTP
                 }
                 break;
             case 'CRAM-MD5':
-                // Start authentication
+                //Start authentication
                 if (!$this->sendCommand('AUTH CRAM-MD5', 'AUTH CRAM-MD5', 334)) {
                     return false;
                 }
-                // Get the challenge
+                //Get the challenge
                 $challenge = base64_decode(substr($this->last_reply, 4));
 
-                // Build the response
+                //Build the response
                 $response = $username . ' ' . $this->hmac($challenge, $password);
 
-                // send encoded credentials
+                //send encoded credentials
                 return $this->sendCommand('Username', base64_encode($response), 235);
             case 'XOAUTH2':
                 //The OAuth instance must be set up prior to requesting auth.
@@ -552,7 +594,7 @@ class SMTP
                 }
                 $oauth = $OAuth->getOauth64();
 
-                // Start authentication
+                //Start authentication
                 if (!$this->sendCommand('AUTH', 'AUTH XOAUTH2 ' . $oauth, 235)) {
                     return false;
                 }
@@ -582,15 +624,15 @@ class SMTP
             return hash_hmac('md5', $data, $key);
         }
 
-        // The following borrowed from
-        // http://php.net/manual/en/function.mhash.php#27225
+        //The following borrowed from
+        //http://php.net/manual/en/function.mhash.php#27225
 
-        // RFC 2104 HMAC implementation for php.
-        // Creates an md5 HMAC.
-        // Eliminates the need to install mhash to compute a HMAC
-        // by Lance Rushing
+        //RFC 2104 HMAC implementation for php.
+        //Creates an md5 HMAC.
+        //Eliminates the need to install mhash to compute a HMAC
+        //by Lance Rushing
 
-        $bytelen = 64; // byte length for md5
+        $bytelen = 64; //byte length for md5
         if (strlen($key) > $bytelen) {
             $key = pack('H*', md5($key));
         }
@@ -613,7 +655,7 @@ class SMTP
         if (is_resource($this->smtp_conn)) {
             $sock_status = stream_get_meta_data($this->smtp_conn);
             if ($sock_status['eof']) {
-                // The socket is valid but we are not connected
+                //The socket is valid but we are not connected
                 $this->edebug(
                     'SMTP NOTICE: EOF caught while checking if connected',
                     self::DEBUG_CLIENT
@@ -623,7 +665,7 @@ class SMTP
                 return false;
             }
 
-            return true; // everything looks good
+            return true; //everything looks good
         }
 
         return false;
@@ -641,7 +683,7 @@ class SMTP
         $this->server_caps = null;
         $this->helo_rply = null;
         if (is_resource($this->smtp_conn)) {
-            // close the connection and cleanup
+            //Close the connection and cleanup
             fclose($this->smtp_conn);
             $this->smtp_conn = null; //Makes for cleaner serialization
             $this->edebug('Connection: closed', self::DEBUG_CONNECTION);
@@ -676,7 +718,7 @@ class SMTP
          * NOTE: this does not count towards line-length limit.
          */
 
-        // Normalize line breaks before exploding
+        //Normalize line breaks before exploding
         $lines = explode("\n", str_replace(["\r\n", "\r"], "\n", $msg_data));
 
         /* To distinguish between a complete RFC822 message and a plain message body, we check if the first field
@@ -722,7 +764,8 @@ class SMTP
 
             //Send the lines to the server
             foreach ($lines_out as $line_out) {
-                //RFC2821 section 4.5.2
+                //Dot-stuffing as per RFC5321 section 4.5.2
+                //https://tools.ietf.org/html/rfc5321#section-4.5.2
                 if (!empty($line_out) && $line_out[0] === '.') {
                     $line_out = '.' . $line_out;
                 }
@@ -756,7 +799,16 @@ class SMTP
     public function hello($host = '')
     {
         //Try extended hello first (RFC 2821)
-        return $this->sendHello('EHLO', $host) or $this->sendHello('HELO', $host);
+        if ($this->sendHello('EHLO', $host)) {
+            return true;
+        }
+
+        //Some servers shut down the SMTP service here (RFC 5321)
+        if (substr($this->helo_rply, 0, 3) == '421') {
+            return false;
+        }
+
+        return $this->sendHello('HELO', $host);
     }
 
     /**
@@ -946,12 +998,12 @@ class SMTP
         $this->client_send($commandstring . static::LE, $command);
 
         $this->last_reply = $this->get_lines();
-        // Fetch SMTP code and possible error code explanation
+        //Fetch SMTP code and possible error code explanation
         $matches = [];
         if (preg_match('/^([\d]{3})[ -](?:([\d]\\.[\d]\\.[\d]{1,2}) )?/', $this->last_reply, $matches)) {
             $code = (int) $matches[1];
             $code_ex = (count($matches) > 2 ? $matches[2] : null);
-            // Cut off error code from each response line
+            //Cut off error code from each response line
             $detail = preg_replace(
                 "/{$code}[ -]" .
                 ($code_ex ? str_replace('.', '\\.', $code_ex) . ' ' : '') . '/m',
@@ -959,7 +1011,7 @@ class SMTP
                 $this->last_reply
             );
         } else {
-            // Fall back to simple parsing if regex fails
+            //Fall back to simple parsing if regex fails
             $code = (int) substr($this->last_reply, 0, 3);
             $code_ex = null;
             $detail = substr($this->last_reply, 4);
@@ -1058,8 +1110,10 @@ class SMTP
     {
         //If SMTP transcripts are left enabled, or debug output is posted online
         //it can leak credentials, so hide credentials in all but lowest level
-        if (self::DEBUG_LOWLEVEL > $this->do_debug &&
-            in_array($command, ['User & Password', 'Username', 'Password'], true)) {
+        if (
+            self::DEBUG_LOWLEVEL > $this->do_debug &&
+            in_array($command, ['User & Password', 'Username', 'Password'], true)
+        ) {
             $this->edebug('CLIENT -> SERVER: [credentials hidden]', self::DEBUG_CLIENT);
         } else {
             $this->edebug('CLIENT -> SERVER: ' . $data, self::DEBUG_CLIENT);
@@ -1152,7 +1206,7 @@ class SMTP
      */
     protected function get_lines()
     {
-        // If the connection is bad, give up straight away
+        //If the connection is bad, give up straight away
         if (!is_resource($this->smtp_conn)) {
             return '';
         }
@@ -1166,24 +1220,52 @@ class SMTP
         $selW = null;
         while (is_resource($this->smtp_conn) && !feof($this->smtp_conn)) {
             //Must pass vars in here as params are by reference
-            if (!stream_select($selR, $selW, $selW, $this->Timelimit)) {
+            //solution for signals inspired by https://github.com/symfony/symfony/pull/6540
+            set_error_handler([$this, 'errorHandler']);
+            $n = stream_select($selR, $selW, $selW, $this->Timelimit);
+            restore_error_handler();
+
+            if ($n === false) {
+                $message = $this->getError()['detail'];
+
+                $this->edebug(
+                    'SMTP -> get_lines(): select failed (' . $message . ')',
+                    self::DEBUG_LOWLEVEL
+                );
+
+                //stream_select returns false when the `select` system call is interrupted
+                //by an incoming signal, try the select again
+                if (stripos($message, 'interrupted system call') !== false) {
+                    $this->edebug(
+                        'SMTP -> get_lines(): retrying stream_select',
+                        self::DEBUG_LOWLEVEL
+                    );
+                    $this->setError('');
+                    continue;
+                }
+
+                break;
+            }
+
+            if (!$n) {
                 $this->edebug(
                     'SMTP -> get_lines(): select timed-out in (' . $this->Timelimit . ' sec)',
                     self::DEBUG_LOWLEVEL
                 );
                 break;
             }
+
             //Deliberate noise suppression - errors are handled afterwards
             $str = @fgets($this->smtp_conn, self::MAX_REPLY_LENGTH);
             $this->edebug('SMTP INBOUND: "' . trim($str) . '"', self::DEBUG_LOWLEVEL);
             $data .= $str;
-            // If response is only 3 chars (not valid, but RFC5321 S4.2 says it must be handled),
-            // or 4th character is a space or a line break char, we are done reading, break the loop.
-            // String array access is a significant micro-optimisation over strlen
+            //If response is only 3 chars (not valid, but RFC5321 S4.2 says it must be handled),
+            //or 4th character is a space or a line break char, we are done reading, break the loop.
+            //String array access is a significant micro-optimisation over strlen
             if (!isset($str[3]) || $str[3] === ' ' || $str[3] === "\r" || $str[3] === "\n") {
                 break;
             }
-            // Timed-out? Log and break
+            //Timed-out? Log and break
             $info = stream_get_meta_data($this->smtp_conn);
             if ($info['timed_out']) {
                 $this->edebug(
@@ -1192,7 +1274,7 @@ class SMTP
                 );
                 break;
             }
-            // Now check if reads took too long
+            //Now check if reads took too long
             if ($endtime && time() > $endtime) {
                 $this->edebug(
                     'SMTP -> get_lines(): timelimit reached (' .