<?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 https://www.gnu.org/licenses/old-licenses/lgpl-2.1.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
* @deprecated This constant will be removed in PHPMailer 8.0. Use `PHPMailer::VERSION` instead.
*/
const VERSION = '7.1.1';
/**
* 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 = (int) $debug_level;
$this->username = self::stripControls($username);
$this->password = self::stripControls($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(function () {
call_user_func_array([$this, 'catchWarning'], func_get_args());
});
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;
}
$username = self::stripControls($username);
$password = self::stripControls($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 +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"
);
}
/**
* Strip all control chars from a string.
*
* @param $string
*
* @return string
*/
protected static function stripControls($string)
{
return preg_replace('/[\x00-\x1F\x7F]/u', '', $string);
}
}