在工作的過程中，經常會有很多應用有發郵件的需求，這個時候需要在每個應用中配置smtp服務器。一旦公司調整了smtp服務器的配置，比如修改了密碼等，這個時候對於維護的人員來說要逐一修改應用中smtp的配置。這樣的情況雖然不多見，但遇上了還是很頭痛的一件事情。
知道了問題，解決起來就有了方向。於是就有了自己開發一個簡單的smtp代理的想法，這個代理主要的功能（參照問題）主要是：
1.接受指定IP應用的smtp請求；
2.應用不需要知道smtp的用戶和密碼；
3.轉發應用的smtp請求。
開發的環境：Linux，php(swoole);
代碼如下：
<?php
/**
*
* SMTP Proxy Server
* @author Terry Zhang, 2015-11-13
*
* @version 1.0
*
* 注意：本程序只能運行在cli模式，且需要擴展Swoole 1.7.20+的支持。
*
* Swoole的源代碼及安裝請參考 https://github.com/swoole/swoole-src/
*
* 本程序的使用場景：
*
* 在多個分散的系統中使用同一的郵件地址進行系統郵件發送時，一旦郵箱密碼修改，則要修改每個系統的郵件配置參數。
* 同時，在每個系統中配置郵箱參數，使得郵箱的密碼容易外洩。
*
* 通過本代理進行郵件發送的客戶端，可以隨便指定用戶名和密碼。
*
*
*/
//error_reporting(0);
defined('DEBUG_ON') or define('DEBUG_ON', false);
//主目錄
defined('BASE_PATH') or define('BASE_PATH', __DIR__);
class CSmtpProxy{
//軟件版本
const VERSION = '1.0';
const EOF = "\r\n";
public static $software = "SMTP-Proxy-Server";
private static $server_mode = SWOOLE_PROCESS;
private static $pid_file;
private static $log_file;
private $smtp_host = 'localhost';
private $smtp_port = 25;
private $smtp_user = '';
private $smtp_pass = '';
private $smtp_from = '';
//待寫入文件的日志隊列（緩沖區）
private $queue = array();
public $host = '0.0.0.0';
public $port = 25;
public $setting = array();
//最大連接數
public $max_connection = 50;
/**
* @var swoole_server
*/
protected $server;
protected $connection = array();
public static function setPidFile($pid_file){
self::$pid_file = $pid_file;
}
public static function start($startFunc){
if(!extension_loaded('swoole')){
exit("Require extension `swoole`.\n");
}
$pid_file = self::$pid_file;
$server_pid = 0;
if(is_file($pid_file)){
$server_pid = file_get_contents($pid_file);
}
global $argv;
if(empty($argv[1])){
goto usage;
}elseif($argv[1] == 'reload'){
if (empty($server_pid)){
exit("SMTP Proxy Server is not running\n");
}
posix_kill($server_pid, SIGUSR1);
exit;
}elseif ($argv[1] == 'stop'){
if (empty($server_pid)){
exit("SMTP Proxy is not running\n");
}
posix_kill($server_pid, SIGTERM);
exit;
}elseif ($argv[1] == 'start'){
//已存在ServerPID，並且進程存在
if (!empty($server_pid) and posix_kill($server_pid,(int) 0)){
exit("SMTP Proxy is already running.\n");
}
//啟動服務器
$startFunc();
}else{
usage:
exit("Usage: php {$argv[0]} start|stop|reload\n");
}
}
public function __construct($host,$port){
$flag = SWOOLE_SOCK_TCP;
$this->server = new swoole_server($host,$port,self::$server_mode,$flag);
$this->host = $host;
$this->port = $port;
$this->setting = array(
'backlog' => 128,
'dispatch_mode' => 2,
);
}
public function daemonize(){
$this->setting['daemonize'] = 1;
}
public function getConnectionInfo($fd){
return $this->server->connection_info($fd);
}
/**
* 啟動服務進程
* @param array $setting
* @throws Exception
*/
public function run($setting = array()){
$this->setting = array_merge($this->setting,$setting);
//不使用swoole的默認日志
if(isset($this->setting['log_file'])){
self::$log_file = $this->setting['log_file'];
unset($this->setting['log_file']);
}
if(isset($this->setting['max_connection'])){
$this->max_connection = $this->setting['max_connection'];
unset($this->setting['max_connection']);
}
if(isset($this->setting['smtp_host'])){
$this->smtp_host = $this->setting['smtp_host'];
unset($this->setting['smtp_host']);
}
if(isset($this->setting['smtp_port'])){
$this->smtp_port = $this->setting['smtp_port'];
unset($this->setting['smtp_port']);
}
if(isset($this->setting['smtp_user'])){
$this->smtp_user = $this->setting['smtp_user'];
unset($this->setting['smtp_user']);
}
if(isset($this->setting['smtp_pass'])){
$this->smtp_pass = $this->setting['smtp_pass'];
unset($this->setting['smtp_pass']);
}
if(isset($this->setting['smtp_from'])){
$this->smtp_from = $this->setting['smtp_from'];
unset($this->setting['smtp_from']);
}
$this->server->set($this->setting);
$version = explode('.', SWOOLE_VERSION);
if($version[0] == 1 && $version[1] < 7 && $version[2] <20){
throw new Exception('Swoole version require 1.7.20 +.');
}
//事件綁定
$this->server->on('start',array($this,'onMasterStart'));
$this->server->on('shutdown',array($this,'onMasterStop'));
$this->server->on('ManagerStart',array($this,'onManagerStart'));
$this->server->on('ManagerStop',array($this,'onManagerStop'));
$this->server->on('WorkerStart',array($this,'onWorkerStart'));
$this->server->on('WorkerStop',array($this,'onWorkerStop'));
$this->server->on('WorkerError',array($this,'onWorkerError'));
$this->server->on('Connect',array($this,'onConnect'));
$this->server->on('Receive',array($this,'onReceive'));
$this->server->on('Close',array($this,'onClose'));
$this->server->start();
}
public function log($msg,$level = 'debug',$flush = false){
if(DEBUG_ON){
$log = date('Y-m-d H:i:s').' ['.$level."]\t" .$msg."\n";
if(!empty(self::$log_file)){
$debug_file = dirname(self::$log_file).'/debug.log';
file_put_contents($debug_file, $log,FILE_APPEND);
if(filesize($debug_file) > 10485760){//10M
unlink($debug_file);
}
}
echo $log;
}
if($level != 'debug'){
//日志記錄
$this->queue[] = date('Y-m-d H:i:s')."\t[".$level."]\t".$msg;
}
if(count($this->queue)>10 && !empty(self::$log_file) || $flush){
if (filesize(self::$log_file) > 209715200){ //200M
rename(self::$log_file,self::$log_file.'.'.date('His'));
}
$logs = '';
foreach ($this->queue as $q){
$logs .= $q."\n";
}
file_put_contents(self::$log_file, $logs,FILE_APPEND);
$this->queue = array();
}
}
public function shutdown(){
return $this->server->shutdown();
}
public function close($fd){
return $this->server->close($fd);
}
public function send($fd,$data){
$data = strtr($data,array("\n" => "", "\0" => "", "\r" => ""));
$this->log("[P --> C]\t" . $data);
return $this->server->send($fd,$data.self::EOF);
}
/*+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ 事件回調
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
public function onMasterStart($serv){
global $argv;
swoole_set_process_name('php '.$argv[0].': master -host='.$this->host.' -port='.$this->port);
if(!empty($this->setting['pid_file'])){
file_put_contents(self::$pid_file, $serv->master_pid);
}
$this->log('Master started.');
}
public function onMasterStop($serv){
if (!empty($this->setting['pid_file'])){
unlink(self::$pid_file);
}
$this->shm->delete();
$this->log('Master stop.');
}
public function onManagerStart($serv){
global $argv;
swoole_set_process_name('php '.$argv[0].': manager');
$this->log('Manager started.');
}
public function onManagerStop($serv){
$this->log('Manager stop.');
}
public function onWorkerStart($serv,$worker_id){
global $argv;
if($worker_id >= $serv->setting['worker_num']) {
swoole_set_process_name("php {$argv[0]}: worker [task]");
} else {
swoole_set_process_name("php {$argv[0]}: worker [{$worker_id}]");
}
$this->log("Worker {$worker_id} started.");
}
public function onWorkerStop($serv,$worker_id){
$this->log("Worker {$worker_id} stop.");
}
public function onWorkerError($serv,$worker_id,$worker_pid,$exit_code){
$this->log("Worker {$worker_id} error:{$exit_code}.");
}
public function onConnect($serv,$fd,$from_id){
if(count($this->server->connections) <= $this->max_connection){
$info = $this->getConnectionInfo($fd);
if($this->isIpAllow($info['remote_ip'])){
//建立服務器連接
$cli = new Client(SWOOLE_SOCK_TCP, SWOOLE_SOCK_ASYNC); //異步非阻塞
$cli->on('connect',array($this,'onServerConnect'));
$cli->on('receive',array($this,'onServerReceive'));
$cli->on('error',array($this,'onServerError'));
$cli->on('close',array($this,'onServerClose'));
$cli->fd = $fd;
$ip = gethostbyname($this->smtp_host);
if($cli->connect($ip,$this->smtp_port) !== false){
$this->connection[$fd] = $cli;
}else{
$this->close($fd);
$this->log('Cannot connect to SMTP server. Connection #'.$fd.' close.');
}
}else{
$this->log('Blocked clinet connection, IP deny : '.$info['remote_ip'],'warn');
$this->server->close($fd);
$this->log('Connection #'.$fd.' close.');
}
}else{
$this->log('Blocked clinet connection, too many connections.','warn');
$this->server->close($fd);
}
}
public function onReceive($serv,$fd,$from_id,$recv_data){
$info = $this->getConnectionInfo($fd);
$this->log("[P <-- C]\t".trim($recv_data));
//禁止使用STARTTLS
if(strtoupper(trim($recv_data)) == 'STARTTLS'){
$this->server->send($fd,"502 Not implemented".self::EOF);
$this->log("[P --> C]\t502 Not implemented");
}else{
//重置登陸驗證
if(preg_match('/^AUTH\s+LOGIN(.*)/', $recv_data,$m)){
$m[1] = trim($m[1]);
if(empty($m[1])){
//只發送AUTH LOGIN 接下來將發送用戶名
$this->connection[$fd]->user = $this->smtp_user;
}else{
$recv_data = 'AUTH LOGIN '.base64_encode($this->smtp_user).self::EOF;
$this->connection[$fd]->pass = $this->smtp_pass;
}
}else{
if(preg_match('/^HELO.*|^EHLO.*/', $recv_data)){
$recv_data = 'HELO '.$this->smtp_host.self::EOF;
}
//重置密碼
if(!empty($this->connection[$fd]->pass)){
$recv_data = base64_encode($this->connection[$fd]->pass).self::EOF;
$this->connection[$fd]->pass = '';
}
//重置用戶名
if(!empty($this->connection[$fd]->user)){
$recv_data = base64_encode($this->connection[$fd]->user).self::EOF;
$this->connection[$fd]->user = '';
$this->connection[$fd]->pass = $this->smtp_pass;
}
//重置mail from
if(preg_match('/^MAIL\s+FROM:.*/', $recv_data)){
$recv_data = 'MAIL FROM:<'.$this->smtp_from.'>'.self::EOF;
}
}
if($this->connection[$fd]->isConnected()){
$this->connection[$fd]->send($recv_data);
$this->log("[P --> S]\t".trim($recv_data));
}
}
}
public function onClose($serv,$fd,$from_id){
if(isset($this->connection[$fd])){
if($this->connection[$fd]->isConnected()){
$this->connection[$fd]->close();
$this->log('Connection on SMTP server close.');
}
}
$this->log('Connection #'.$fd.' close. Flush the logs.','debug',true);
}
/*---------------------------------------------
*
* 服務器連接事件回調
*
----------------------------------------------*/
public function onServerConnect($cli){
$this->log('Connected to SMTP server.');
}
public function onServerReceive($cli,$data){
$this->log("[P <-- S]\t".trim($data));
if($this->server->send($cli->fd,$data)){
$this->log("[P --> C]\t".trim($data));
}
}
public function onServerError($cli){
$this->server->close($cli->fd);
$this->log('Connection on SMTP server error: '.$cli->errCode.' '.socket_strerror($cli->errCode),'warn');
}
public function onServerClose($cli){
$this->log('Connection on SMTP server close.');
$this->server->close($cli->fd);
}
/**
* IP地址過濾
* @param unknown $ip
* @return boolean
*/
public function isIpAllow($ip){
$pass = false;
if(isset($this->setting['ip']['allow'])){
foreach ($this->setting['ip']['allow'] as $addr){
$pattern = '/'.str_replace('*','\d+',str_replace('.', '\.', $addr)).'/';
if(preg_match($pattern, $ip) && !empty($addr)){
$pass = true;
break;
}
}
}
if($pass){
if(isset($this->setting['ip']['deny'])){
foreach ($this->setting['ip']['deny'] as $addr){
$pattern = '/'.str_replace('*','\d+',str_replace('.', '\.', $addr)).'/';
if(preg_match($pattern, $ip) && !empty($addr)){
$pass = false;
break;
}
}
}
}
return $pass;
}
}
class Client extends swoole_client{
/**
* 記錄當前連接
* @var unknown
*/
public $fd ;
public $user = '';
/**
* smtp登陸密碼
* @var unknown
*/
public $pass = '';
}
配置文件例子：
/**
* 運行配置
*/
return array(
'worker_num' => 12,
'log_file' => BASE_PATH.'/logs/proxyserver.log',
'pid_file' => BASE_PATH.'/logs/proxyserver.pid',
'heartbeat_idle_time' => 300,
'heartbeat_check_interval' => 60,
'max_connection' => 50,
//配置真實的smtp信息
'smtp_host' => '',
'smtp_port' => 25,
'smtp_user' => '',
'smtp_pass' => '',
'smtp_from' => '',
'ip' => array(
'allow' => array('192.168.0.*'),
'deny' => array('192.168.10.*','192.168.100.*'),
)
);
運行例子：
defined('BASE_PATH') or define('BASE_PATH', __DIR__);
defined('DEBUG_ON') or define('DEBUG_ON', true);
//服務器配置
require BASE_PATH.'/CSmtpProxy.php';
$settings = require BASE_PATH.'/conf/config.php';
CSmtpProxy::setPidFile($settings['pid_file']);
CSmtpProxy::start(function(){
global $settings;
$serv = new CSmtpProxy('0.0.0.0', 25);
$serv->daemonize();
$serv->run($settings);
});
應用配置：
smtp host: 192.168.0.* //指定smtpproxy 運行的服務器IP。
port: 25
user: xxxx //隨意填寫
pass: xxxx //隨意填寫
from: [email protected] // 根據情況填寫
——————————————————————————————————————————————————————
存在的問題：
1、不支持ssl模式；
2、應用的from還是要填寫正確，否則發出的郵件發件人會顯示錯誤。
