Project import generated by Copybara.
GitOrigin-RevId: 63746295f1a5ab5a619056791995793d65529e62
diff --git a/src/lib/PHPMailer/POP3.php b/src/lib/PHPMailer/POP3.php
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+<?php
+
+/**
+ * PHPMailer POP-Before-SMTP Authentication Class.
+ * PHP Version 5.5.
+ *
+ * @see https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
+ *
+ * @author Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author Brent R. Matzelle (original founder)
+ * @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
+ * @note This program is distributed in the hope that it will be useful - WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace PHPMailer\PHPMailer;
+
+/**
+ * PHPMailer POP-Before-SMTP Authentication Class.
+ * Specifically for PHPMailer to use for RFC1939 POP-before-SMTP authentication.
+ * 1) This class does not support APOP authentication.
+ * 2) Opening and closing lots of POP3 connections can be quite slow. If you need
+ * to send a batch of emails then just perform the authentication once at the start,
+ * and then loop through your mail sending script. Providing this process doesn't
+ * take longer than the verification period lasts on your POP3 server, you should be fine.
+ * 3) This is really ancient technology; you should only need to use it to talk to very old systems.
+ * 4) This POP3 class is deliberately lightweight and incomplete, implementing just
+ * enough to do authentication.
+ * If you want a more complete class there are other POP3 classes for PHP available.
+ *
+ * @author Richard Davey (original author) <rich@corephp.co.uk>
+ * @author Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ */
+class POP3
+{
+ /**
+ * The POP3 PHPMailer Version number.
+ *
+ * @var string
+ */
+ const VERSION = '6.8.1';
+
+ /**
+ * Default POP3 port number.
+ *
+ * @var int
+ */
+ const DEFAULT_PORT = 110;
+
+ /**
+ * Default timeout in seconds.
+ *
+ * @var int
+ */
+ const DEFAULT_TIMEOUT = 30;
+
+ /**
+ * POP3 class debug output mode.
+ * Debug output level.
+ * Options:
+ * @see POP3::DEBUG_OFF: No output
+ * @see POP3::DEBUG_SERVER: Server messages, connection/server errors
+ * @see POP3::DEBUG_CLIENT: Client and Server messages, connection/server errors
+ *
+ * @var int
+ */
+ public $do_debug = self::DEBUG_OFF;
+
+ /**
+ * POP3 mail server hostname.
+ *
+ * @var string
+ */
+ public $host;
+
+ /**
+ * POP3 port number.
+ *
+ * @var int
+ */
+ public $port;
+
+ /**
+ * POP3 Timeout Value in seconds.
+ *
+ * @var int
+ */
+ public $tval;
+
+ /**
+ * POP3 username.
+ *
+ * @var string
+ */
+ public $username;
+
+ /**
+ * POP3 password.
+ *
+ * @var string
+ */
+ public $password;
+
+ /**
+ * Resource handle for the POP3 connection socket.
+ *
+ * @var resource
+ */
+ protected $pop_conn;
+
+ /**
+ * Are we connected?
+ *
+ * @var bool
+ */
+ protected $connected = false;
+
+ /**
+ * Error container.
+ *
+ * @var array
+ */
+ protected $errors = [];
+
+ /**
+ * Line break constant.
+ */
+ const LE = "\r\n";
+
+ /**
+ * Debug level for no output.
+ *
+ * @var int
+ */
+ const DEBUG_OFF = 0;
+
+ /**
+ * Debug level to show server -> client messages
+ * also shows clients connection errors or errors from server
+ *
+ * @var int
+ */
+ const DEBUG_SERVER = 1;
+
+ /**
+ * Debug level to show client -> server and server -> client messages.
+ *
+ * @var int
+ */
+ const DEBUG_CLIENT = 2;
+
+ /**
+ * Simple static wrapper for all-in-one POP before SMTP.
+ *
+ * @param string $host The hostname to connect to
+ * @param int|bool $port The port number to connect to
+ * @param int|bool $timeout The timeout value
+ * @param string $username
+ * @param string $password
+ * @param int $debug_level
+ *
+ * @return bool
+ */
+ public static function popBeforeSmtp(
+ $host,
+ $port = false,
+ $timeout = false,
+ $username = '',
+ $password = '',
+ $debug_level = 0
+ ) {
+ $pop = new self();
+
+ return $pop->authorise($host, $port, $timeout, $username, $password, $debug_level);
+ }
+
+ /**
+ * Authenticate with a POP3 server.
+ * A connect, login, disconnect sequence
+ * appropriate for POP-before SMTP authorisation.
+ *
+ * @param string $host The hostname to connect to
+ * @param int|bool $port The port number to connect to
+ * @param int|bool $timeout The timeout value
+ * @param string $username
+ * @param string $password
+ * @param int $debug_level
+ *
+ * @return bool
+ */
+ public function authorise($host, $port = false, $timeout = false, $username = '', $password = '', $debug_level = 0)
+ {
+ $this->host = $host;
+ //If no port value provided, use default
+ if (false === $port) {
+ $this->port = static::DEFAULT_PORT;
+ } else {
+ $this->port = (int) $port;
+ }
+ //If no timeout value provided, use default
+ if (false === $timeout) {
+ $this->tval = static::DEFAULT_TIMEOUT;
+ } else {
+ $this->tval = (int) $timeout;
+ }
+ $this->do_debug = $debug_level;
+ $this->username = $username;
+ $this->password = $password;
+ //Reset the error log
+ $this->errors = [];
+ //Connect
+ $result = $this->connect($this->host, $this->port, $this->tval);
+ if ($result) {
+ $login_result = $this->login($this->username, $this->password);
+ if ($login_result) {
+ $this->disconnect();
+
+ return true;
+ }
+ }
+ //We need to disconnect regardless of whether the login succeeded
+ $this->disconnect();
+
+ return false;
+ }
+
+ /**
+ * Connect to a POP3 server.
+ *
+ * @param string $host
+ * @param int|bool $port
+ * @param int $tval
+ *
+ * @return bool
+ */
+ public function connect($host, $port = false, $tval = 30)
+ {
+ //Are we already connected?
+ if ($this->connected) {
+ return true;
+ }
+
+ //On Windows this will raise a PHP Warning error if the hostname doesn't exist.
+ //Rather than suppress it with @fsockopen, capture it cleanly instead
+ set_error_handler([$this, 'catchWarning']);
+
+ if (false === $port) {
+ $port = static::DEFAULT_PORT;
+ }
+
+ //Connect to the POP3 server
+ $errno = 0;
+ $errstr = '';
+ $this->pop_conn = fsockopen(
+ $host, //POP3 Host
+ $port, //Port #
+ $errno, //Error Number
+ $errstr, //Error Message
+ $tval
+ ); //Timeout (seconds)
+ //Restore the error handler
+ restore_error_handler();
+
+ //Did we connect?
+ if (false === $this->pop_conn) {
+ //It would appear not...
+ $this->setError(
+ "Failed to connect to server $host on port $port. errno: $errno; errstr: $errstr"
+ );
+
+ return false;
+ }
+
+ //Increase the stream time-out
+ stream_set_timeout($this->pop_conn, $tval, 0);
+
+ //Get the POP3 server response
+ $pop3_response = $this->getResponse();
+ //Check for the +OK
+ if ($this->checkResponse($pop3_response)) {
+ //The connection is established and the POP3 server is talking
+ $this->connected = true;
+
+ return true;
+ }
+
+ return false;
+ }
+
+ /**
+ * Log in to the POP3 server.
+ * Does not support APOP (RFC 2828, 4949).
+ *
+ * @param string $username
+ * @param string $password
+ *
+ * @return bool
+ */
+ public function login($username = '', $password = '')
+ {
+ if (!$this->connected) {
+ $this->setError('Not connected to POP3 server');
+ return false;
+ }
+ if (empty($username)) {
+ $username = $this->username;
+ }
+ if (empty($password)) {
+ $password = $this->password;
+ }
+
+ //Send the Username
+ $this->sendString("USER $username" . static::LE);
+ $pop3_response = $this->getResponse();
+ if ($this->checkResponse($pop3_response)) {
+ //Send the Password
+ $this->sendString("PASS $password" . static::LE);
+ $pop3_response = $this->getResponse();
+ if ($this->checkResponse($pop3_response)) {
+ return true;
+ }
+ }
+
+ return false;
+ }
+
+ /**
+ * Disconnect from the POP3 server.
+ */
+ public function disconnect()
+ {
+ // If could not connect at all, no need to disconnect
+ if ($this->pop_conn === false) {
+ return;
+ }
+
+ $this->sendString('QUIT' . static::LE);
+
+ // RFC 1939 shows POP3 server sending a +OK response to the QUIT command.
+ // Try to get it. Ignore any failures here.
+ try {
+ $this->getResponse();
+ } catch (Exception $e) {
+ //Do nothing
+ }
+
+ //The QUIT command may cause the daemon to exit, which will kill our connection
+ //So ignore errors here
+ try {
+ @fclose($this->pop_conn);
+ } catch (Exception $e) {
+ //Do nothing
+ }
+
+ // Clean up attributes.
+ $this->connected = false;
+ $this->pop_conn = false;
+ }
+
+ /**
+ * Get a response from the POP3 server.
+ *
+ * @param int $size The maximum number of bytes to retrieve
+ *
+ * @return string
+ */
+ protected function getResponse($size = 128)
+ {
+ $response = fgets($this->pop_conn, $size);
+ if ($this->do_debug >= self::DEBUG_SERVER) {
+ echo 'Server -> Client: ', $response;
+ }
+
+ return $response;
+ }
+
+ /**
+ * Send raw data to the POP3 server.
+ *
+ * @param string $string
+ *
+ * @return int
+ */
+ protected function sendString($string)
+ {
+ if ($this->pop_conn) {
+ if ($this->do_debug >= self::DEBUG_CLIENT) { //Show client messages when debug >= 2
+ echo 'Client -> Server: ', $string;
+ }
+
+ return fwrite($this->pop_conn, $string, strlen($string));
+ }
+
+ return 0;
+ }
+
+ /**
+ * Checks the POP3 server response.
+ * Looks for for +OK or -ERR.
+ *
+ * @param string $string
+ *
+ * @return bool
+ */
+ protected function checkResponse($string)
+ {
+ if (strpos($string, '+OK') !== 0) {
+ $this->setError("Server reported an error: $string");
+
+ return false;
+ }
+
+ return true;
+ }
+
+ /**
+ * Add an error to the internal error store.
+ * Also display debug output if it's enabled.
+ *
+ * @param string $error
+ */
+ protected function setError($error)
+ {
+ $this->errors[] = $error;
+ if ($this->do_debug >= self::DEBUG_SERVER) {
+ echo '<pre>';
+ foreach ($this->errors as $e) {
+ print_r($e);
+ }
+ echo '</pre>';
+ }
+ }
+
+ /**
+ * Get an array of error messages, if any.
+ *
+ * @return array
+ */
+ public function getErrors()
+ {
+ return $this->errors;
+ }
+
+ /**
+ * POP3 connection error handler.
+ *
+ * @param int $errno
+ * @param string $errstr
+ * @param string $errfile
+ * @param int $errline
+ */
+ protected function catchWarning($errno, $errstr, $errfile, $errline)
+ {
+ $this->setError(
+ 'Connecting to the POP3 server raised a PHP warning:' .
+ "errno: $errno errstr: $errstr; errfile: $errfile; errline: $errline"
+ );
+ }
+}