PHP SMTP邮件发送类，支持SSL连接

<?php
/**
* 邮件发送类
* 支持发送纯文本邮件和HTML格式的邮件，可以多收件人，多抄送，多秘密抄送，带附件(单个或多个附件),支持到服务器的ssl连接
* 需要的php扩展：sockets、Fileinfo和openssl。
* 编码格式是UTF-8，传输编码格式是base64
* @example
* $mail = new MySendMail();
* $mail->setServer("smtp@126.com", "XXXXX@126.com", "XXXXX"); //设置smtp服务器，普通连接方式
* $mail->setServer("smtp.gmail.com", "XXXXX@gmail.com", "XXXXX", 465, true); //设置smtp服务器，到服务器的SSL连接
* $mail->setFrom("XXXXX"); //设置发件人
* $mail->setReceiver("XXXXX"); //设置收件人，多个收件人，调用多次
* $mail->setCc("XXXX"); //设置抄送，多个抄送，调用多次
* $mail->setBcc("XXXXX"); //设置秘密抄送，多个秘密抄送，调用多次
* $mail->addAttachment("XXXX"); //添加附件，多个附件，调用多次
* $mail->setMail("test", "<b>test</b>"); //设置邮件主题、内容
* $mail->sendMail(); //发送
*/
class MySendMail {
	/**
	* @var string 邮件传输代理用户名
	* @access protected
	*/
	protected $_userName;

	/**
	* @var string 邮件传输代理密码
	* @access protected
	*/
	protected $_password;

	/**
	* @var string 邮件传输代理服务器地址
	* @access protected
	*/
	protected $_sendServer;

	/**
	* @var int 邮件传输代理服务器端口
	* @access protected
	*/
	protected $_port;

	/**
	* @var string 发件人
	* @access protected
	*/
	protected $_from;

	/**
	* @var array 收件人
	* @access protected
	*/
	protected $_to = array();

	/**
	* @var array 抄送
	* @access protected
	*/
	protected $_cc = array();

	/**
	* @var array 秘密抄送
	* @access protected
	*/
	protected $_bcc = array();

	/**
	* @var string 主题
	* @access protected
	*/
	protected $_subject;

	/**
	* @var string 邮件正文
	* @access protected
	*/
	protected $_body;

	/**
	* @var array 附件
	* @access protected
	*/
	protected $_attachment = array();

	/**
	* @var reource socket资源
	* @access protected
	*/
	protected $_socket;

	/**
	* @var reource 是否是安全连接
	* @access protected
	*/
	protected $_isSecurity;

	/**
	* @var string 错误信息
	* @access protected
	*/
	protected $_errorMessage;


	/**
	* 设置邮件传输代理，如果是可以匿名发送有邮件的服务器，只需传递代理服务器地址就行
	* @access public
	* @param string $server 代理服务器的ip或者域名
	* @param string $username 认证账号
	* @param string $password 认证密码
	* @param int $port 代理服务器的端口，smtp默认25号端口
	* @param boolean $isSecurity 到服务器的连接是否为安全连接，默认false
	* @return boolean
	*/
	public function setServer($server, $username="", $password="", $port=25, $isSecurity=false) {
		$this->_sendServer = $server;
		$this->_port = $port;
		$this->_isSecurity = $isSecurity;
		$this->_userName = empty($username) ? "" : base64_encode($username);
		$this->_password = empty($password) ? "" : base64_encode($password);
		return true;
	}

	/**
	* 设置发件人
	* @access public
	* @param string $from 发件人地址
	* @return boolean
	*/
	public function setFrom($from) {
		$this->_from = $from;
		return true;
	}

	/**
	* 设置收件人，多个收件人，调用多次.
	* @access public
	* @param string $to 收件人地址
	* @return boolean
	*/
	public function setReceiver($to) {
		$this->_to[] = $to;
		return true;
	}

	/**
	* 设置抄送，多个抄送，调用多次.
	* @access public
	* @param string $cc 抄送地址
	* @return boolean
	*/
	public function setCc($cc) {
		$this->_cc[] = $cc;
		return true;
	}

	/**
	* 设置秘密抄送，多个秘密抄送，调用多次
	* @access public
	* @param string $bcc 秘密抄送地址
	* @return boolean
	*/
	public function setBcc($bcc) {
		$this->_bcc[] = $bcc;
		return true;
	}

	/**
	* 设置邮件附件，多个附件，调用多次
	* @access public
	* @param string $file 文件地址
	* @return boolean
	*/
	public function addAttachment($file) {
		if(!file_exists($file)) {
			$this->_errorMessage = "file " . $file . " does not exist.";
			return false;
		}
		$this->_attachment[] = $file;
		return true;
	}

	/**
	* 设置邮件信息
	* @access public
	* @param string $body 邮件主题
	* @param string $subject 邮件主体内容，可以是纯文本，也可是是HTML文本
	* @return boolean
	*/
	public function setMail($subject, $body) {
		$this->_subject = base64_encode($subject);
		$this->_body = base64_encode($body);
		return true;
	}

	/**
	* 发送邮件
	* @access public
	* @return boolean
	*/
	public function sendMail() {
		$command = $this->getCommand();

		$this->_isSecurity ? $this->socketSecurity() : $this->socket();
		
		foreach ($command as $value) {
			$result = $this->_isSecurity ? $this->sendCommandSecurity($value[0], $value[1]) : $this->sendCommand($value[0], $value[1]);
			if($result) {
				continue;
			}
			else{
				return false;
			}
		}
		
		//其实这里也没必要关闭，smtp命令：QUIT发出之后，服务器就关闭了连接，本地的socket资源会自动释放
		$this->_isSecurity ? $this->closeSecutity() : $this->close();
		return true;
	}

	/**
	* 返回错误信息
	* @return string
	*/
	public function error(){
		if(!isset($this->_errorMessage)) {
			$this->_errorMessage = "";
		}
		return $this->_errorMessage;
	}

	/**
	* 返回mail命令
	* @access protected
	* @return array
	*/
	protected function getCommand() {
		$separator = "----=_Part_" . md5($this->_from . time()) . uniqid(); //分隔符

		$command = array(
				array("HELO sendmail\r\n", 250)
			);
		if(!empty($this->_userName)){
			$command[] = array("AUTH LOGIN\r\n", 334);
			$command[] = array($this->_userName . "\r\n", 334);
			$command[] = array($this->_password . "\r\n", 235);
		}

		//设置发件人
		$command[] = array("MAIL FROM: <" . $this->_from . ">\r\n", 250);
		$header = "FROM: <" . $this->_from . ">\r\n";

		//设置收件人
		if(!empty($this->_to)) {
			$count = count($this->_to);
			if($count == 1){
				$command[] = array("RCPT TO: <" . $this->_to[0] . ">\r\n", 250);
				$header .= "TO: <" . $this->_to[0] .">\r\n";
			}
			else{
				for($i=0; $i<$count; $i++){
					$command[] = array("RCPT TO: <" . $this->_to[$i] . ">\r\n", 250);
					if($i == 0){
						$header .= "TO: <" . $this->_to[$i] .">";
					}
					elseif($i + 1 == $count){
						$header .= ",<" . $this->_to[$i] .">\r\n";
					}
					else{
						$header .= ",<" . $this->_to[$i] .">";
					}
				}
			}
		}

		//设置抄送
		if(!empty($this->_cc)) {
			$count = count($this->_cc);
			if($count == 1){
				$command[] = array("RCPT TO: <" . $this->_cc[0] . ">\r\n", 250);
				$header .= "CC: <" . $this->_cc[0] .">\r\n";
			}
			else{
				for($i=0; $i<$count; $i++){
					$command[] = array("RCPT TO: <" . $this->_cc[$i] . ">\r\n", 250);
					if($i == 0){
					$header .= "CC: <" . $this->_cc[$i] .">";
					}
					elseif($i + 1 == $count){
						$header .= ",<" . $this->_cc[$i] .">\r\n";
					}
					else{
						$header .= ",<" . $this->_cc[$i] .">";
					}
				}
			}
		}

		//设置秘密抄送
		if(!empty($this->_bcc)) {
			$count = count($this->_bcc);
			if($count == 1) {
				$command[] = array("RCPT TO: <" . $this->_bcc[0] . ">\r\n", 250);
				$header .= "BCC: <" . $this->_bcc[0] .">\r\n";
			}
			else{
				for($i=0; $i<$count; $i++){
					$command[] = array("RCPT TO: <" . $this->_bcc[$i] . ">\r\n", 250);
					if($i == 0){
					$header .= "BCC: <" . $this->_bcc[$i] .">";
					}
					elseif($i + 1 == $count){
						$header .= ",<" . $this->_bcc[$i] .">\r\n";
					}
					else{
						$header .= ",<" . $this->_bcc[$i] .">";
					}
				}
			}
		}

		//主题
		$header .= "Subject: =?UTF-8?B?" . $this->_subject ."?=\r\n";
		if(isset($this->_attachment)) {
			//含有附件的邮件头需要声明成这个
			$header .= "Content-Type: multipart/mixed;\r\n";
		}
		elseif(false){
			//邮件体含有图片资源的,且包含的图片在邮件内部时声明成这个，如果是引用的远程图片，就不需要了
			$header .= "Content-Type: multipart/related;\r\n";
		}
		else{
			//html或者纯文本的邮件声明成这个
			$header .= "Content-Type: multipart/alternative;\r\n";
		}

		//邮件头分隔符
		$header .= "\t" . 'boundary="' . $separator . '"';

		$header .= "\r\nMIME-Version: 1.0\r\n";

		//这里开始是邮件的body部分，body部分分成几段发送
		$header .= "\r\n--" . $separator . "\r\n";
		$header .= "Content-Type:text/html; charset=utf-8\r\n";
		$header .= "Content-Transfer-Encoding: base64\r\n\r\n";
		$header .= $this->_body . "\r\n";
		$header .= "--" . $separator . "\r\n";

		//加入附件
		if(!empty($this->_attachment)){
			$count = count($this->_attachment);
			for($i=0; $i<$count; $i++){
				$header .= "\r\n--" . $separator . "\r\n";
				$header .= "Content-Type: " . $this->getMIMEType($this->_attachment[$i]) . '; name="=?UTF-8?B?' . base64_encode( basename($this->_attachment[$i]) ) . '?="' . "\r\n";
				$header .= "Content-Transfer-Encoding: base64\r\n";
				$header .= 'Content-Disposition: attachment; filename="=?UTF-8?B?' . base64_encode( basename($this->_attachment[$i]) ) . '?="' . "\r\n";
				$header .= "\r\n";
				$header .= $this->readFile($this->_attachment[$i]);
				$header .= "\r\n--" . $separator . "\r\n";
			}
		}

		//结束邮件数据发送
		$header .= "\r\n.\r\n";


		$command[] = array("DATA\r\n", 354);
		$command[] = array($header, 250);
		$command[] = array("QUIT\r\n", 221);
		
		return $command;
	}

	/**
	* 发送命令
	* @access protected
	* @param string $command 发送到服务器的smtp命令
	* @param int $code 期望服务器返回的响应吗
	* @return boolean
	*/
	protected function sendCommand($command, $code) {
		echo 'Send command:' . $command . ',expected code:' . $code . '<br />';
		//发送命令给服务器
		try{
			if(socket_write($this->_socket, $command, strlen($command))){

				//当邮件内容分多次发送时，没有$code，服务器没有返回
				if(empty($code))  {
					return true;
				}

				//读取服务器返回
				$data = trim(socket_read($this->_socket, 1024));
				echo 'response:' . $data . '<br /><br />';

				if($data) {
					$pattern = "/^".$code."+?/";
					if(preg_match($pattern, $data)) {
						return true;
					}
					else{
						$this->_errorMessage = "Error:" . $data . "|**| command:";
						return false;
					}
				}
				else{
					$this->_errorMessage = "Error:" . socket_strerror(socket_last_error());
					return false;
				}
			}
			else{
				$this->_errorMessage = "Error:" . socket_strerror(socket_last_error());
				return false;
			}
		}catch(Exception $e) {
			$this->_errorMessage = "Error:" . $e->getMessage();
		}
	}

	/**
	* 安全连接发送命令
	* @access protected
	* @param string $command 发送到服务器的smtp命令
	* @param int $code 期望服务器返回的响应吗
	* @return boolean
	*/
	protected function sendCommandSecurity($command, $code) {
		echo 'Send command:' . $command . ',expected code:' . $code . '<br />';
		try {
			if(fwrite($this->_socket, $command)){
				//当邮件内容分多次发送时，没有$code，服务器没有返回
				if(empty($code))  {
					return true;
				}
				//读取服务器返回
				$data = trim(fread($this->_socket, 1024));
				echo 'response:' . $data . '<br /><br />';

				if($data) {
					$pattern = "/^".$code."+?/";
					if(preg_match($pattern, $data)) {
						return true;
					}
					else{
						$this->_errorMessage = "Error:" . $data . "|**| command:";
						return false;
					}
				}
				else{
					return false;
				}
			}
			else{
				$this->_errorMessage = "Error: " . $command . " send failed";
				return false;
			}
		}catch(Exception $e) {
			$this->_errorMessage = "Error:" . $e->getMessage();
		}
	} 

	/**
	* 读取附件文件内容，返回base64编码后的文件内容
	* @access protected
	* @param string $file 文件
	* @return mixed
	*/
	protected function readFile($file) {
		if(file_exists($file)) {
			$file_obj = file_get_contents($file);
			return base64_encode($file_obj);
		}
		else {
			$this->_errorMessage = "file " . $file . " dose not exist";
			return false;
		}
	}

	/**
	* 获取附件MIME类型
	* @access protected
	* @param string $file 文件
	* @return mixed
	*/
	protected function getMIMEType($file) {
		if(file_exists($file)) {
			$mime = mime_content_type($file);
			/*if(! preg_match("/gif|jpg|png|jpeg/", $mime)){
				$mime = "application/octet-stream";
			}*/
			return $mime;
		}
		else {
			return false;
		}
	}

	/**
	* 建立到服务器的网络连接
	* @access protected
	* @return boolean
	*/
	protected function socket() {
		//创建socket资源
		$this->_socket = socket_create(AF_INET, SOCK_STREAM, getprotobyname('tcp'));
		
		if(!$this->_socket) {
			$this->_errorMessage = socket_strerror(socket_last_error());
			return false;
		}

		socket_set_block($this->_socket);//设置阻塞模式

		//连接服务器
		if(!socket_connect($this->_socket, $this->_sendServer, $this->_port)) {
			$this->_errorMessage = socket_strerror(socket_last_error());
			return false;
		}
		$str = socket_read($this->_socket, 1024);
		if(!preg_match("/220+?/", $str)){
			$this->_errorMessage = $str;
			return false;
		}
		
		return true;
	}

	/**
	* 建立到服务器的SSL网络连接
	* @access protected
	* @return boolean
	*/
	protected function socketSecurity() {
		$remoteAddr = "tcp://" . $this->_sendServer . ":" . $this->_port;
		$this->_socket = stream_socket_client($remoteAddr, $errno, $errstr, 30);
		if(!$this->_socket){
			$this->_errorMessage = $errstr;
			return false;
		}

		//设置加密连接，默认是ssl，如果需要tls连接，可以查看php手册stream_socket_enable_crypto函数的解释
		stream_socket_enable_crypto($this->_socket, true, STREAM_CRYPTO_METHOD_SSLv23_CLIENT);

		stream_set_blocking($this->_socket, 1); //设置阻塞模式
		$str = fread($this->_socket, 1024);
		if(!preg_match("/220+?/", $str)){
			$this->_errorMessage = $str;
			return false;
		}

		return true;
	}

	/**
	* 关闭socket
	* @access protected
	* @return boolean
	*/
	protected function close() {
		if(isset($this->_socket) && is_object($this->_socket)) {
			$this->_socket->close();
			return true;
		}
		$this->_errorMessage = "No resource can to be close";
		return false;
	}

	/**
	* 关闭安全socket
	* @access protected
	* @return boolean
	*/
	protected function closeSecutity() {
		if(isset($this->_socket) && is_object($this->_socket)) {
			stream_socket_shutdown($this->_socket, STREAM_SHUT_WR);
			return true;
		}
		$this->_errorMessage = "No resource can to be close";
		return false;
	}
}