class/deliver/Deliver_SMTP.class.php

   1 <?php
   2
   3 /**
   4  * Deliver_SMTP.class.php
   5  *
   6  * SMTP delivery backend for the Deliver class.
   7  *
   8  * @copyright &copy; 1999-2006 The SquirrelMail Project Team
   9  * @license http://opensource.org/licenses/gpl-license.php GNU Public License
  10  * @version $Id$
  11  * @package squirrelmail
  12  */
  13
  14 /** @ignore */
  15 if (!defined('SM_PATH')) define('SM_PATH','../../');
  16
  17 /** This of course depends upon Deliver */
  18 include_once(SM_PATH . 'class/deliver/Deliver.class.php');
  19
  20 /**
  21  * Deliver messages using SMTP
  22  * @package squirrelmail
  23  */
  24 class Deliver_SMTP extends Deliver {
  25     /**
  26      * Array keys are uppercased ehlo keywords
  27      * array key values are ehlo params. If ehlo-param contains space, it is splitted into array.
  28      * @var array ehlo
  29      * @since 1.5.1
  30      */
  31     var $ehlo = array();
  32     /**
  33      * @var string domain
  34      * @since 1.5.1
  35      */
  36     var $domain = '';
  37     /**
  38      * SMTP STARTTLS rfc: "Both the client and the server MUST know if there
  39      * is a TLS session active."
  40      * Variable should be set to true, when encryption is turned on.
  41      * @var boolean
  42      * @since 1.5.1
  43      */
  44     var $tls_enabled = false;
  45     /**
  46      * Private var
  47      * var stream $stream
  48      * @todo don't pass stream resource in class method arguments.
  49      */
  50     //var $stream = false;
  51     /** @var string delivery error message */
  52     var $dlv_msg = '';
  53     /** @var integer delivery error number from server */
  54     var $dlv_ret_nr = '';
  55     /** @var string delivery error message from server */
  56     var $dlv_server_msg = '';
  57
  58     function preWriteToStream(&$s) {
  59         if ($s) {
  60             if ($s{0} == '.')   $s = '.' . $s;
  61             $s = str_replace("\n.","\n..",$s);
  62         }
  63     }
  64
  65     function initStream($message, $domain, $length=0, $host='', $port='', $user='', $pass='', $authpop=false) {
  66         global $use_smtp_tls,$smtp_auth_mech;
  67
  68         if ($authpop) {
  69             $this->authPop($host, '', $user, $pass);
  70         }
  71
  72         $rfc822_header = $message->rfc822_header;
  73
  74         $from = $rfc822_header->from[0];
  75         $to =   $rfc822_header->to;
  76         $cc =   $rfc822_header->cc;
  77         $bcc =  $rfc822_header->bcc;
  78         $content_type  = $rfc822_header->content_type;
  79
  80         // MAIL FROM: <from address> MUST be empty in cae of MDN (RFC2298)
  81         if ($content_type->type0 == 'multipart' &&
  82             $content_type->type1 == 'report' &&
  83             isset($content_type->properties['report-type']) &&
  84             $content_type->properties['report-type']=='disposition-notification') {
  85             $from->host = '';
  86             $from->mailbox = '';
  87         }
  88
  89         if ($use_smtp_tls == 1) {
  90             if ((check_php_version(4,3)) && (extension_loaded('openssl'))) {
  91                 $stream = @fsockopen('tls://' . $host, $port, $errorNumber, $errorString);
  92                 $this->tls_enabled = true;
  93             } else {
  94                 /**
  95                  * don't connect to server when user asks for smtps and
  96                  * PHP does not support it.
  97                  */
  98                 $errorNumber = '';
  99                 $errorString = _("Secure SMTP (TLS) is enabled in SquirrelMail configuration, but used PHP version does not support it.");
 100             }
 101         } else {
 102             $stream = @fsockopen($host, $port, $errorNumber, $errorString);
 103         }
 104
 105         if (!$stream) {
 106             // reset tls state var to default value, if connection fails
 107             $this->tls_enabled = false;
 108             // set error messages
 109             $this->dlv_msg = $errorString;
 110             $this->dlv_ret_nr = $errorNumber;
 111             $this->dlv_server_msg = _("Can't open SMTP stream.");
 112             return(0);
 113         }
 114         // get server greeting
 115         $tmp = fgets($stream, 1024);
 116         if ($this->errorCheck($tmp, $stream)) {
 117             return(0);
 118         }
 119
 120         /*
 121          * If $_SERVER['HTTP_HOST'] is set, use that in our HELO to the SMTP
 122          * server.  This should fix the DNS issues some people have had
 123          */
 124         if (sqgetGlobalVar('HTTP_HOST', $HTTP_HOST, SQ_SERVER)) { // HTTP_HOST is set
 125             // optionally trim off port number
 126             if($p = strrpos($HTTP_HOST, ':')) {
 127                 $HTTP_HOST = substr($HTTP_HOST, 0, $p);
 128             }
 129             $helohost = $HTTP_HOST;
 130         } else { // For some reason, HTTP_HOST is not set - revert to old behavior
 131             $helohost = $domain;
 132         }
 133
 134         /* Lets introduce ourselves */
 135         fputs($stream, "EHLO $helohost\r\n");
 136         // Read ehlo response
 137         $tmp = $this->parse_ehlo_response($stream);
 138         if ($this->errorCheck($tmp,$stream)) {
 139             // fall back to HELO if EHLO is not supported
 140             if ($this->dlv_ret_nr == '500') {
 141                 fputs($stream, "HELO $helohost\r\n");
 142                 $tmp = fgets($stream,1024);
 143                 if ($this->errorCheck($tmp,$stream)) {
 144                     return(0);
 145                 }
 146             } else {
 147                 return(0);
 148             }
 149         }
 150
 151         /**
 152          * Implementing SMTP STARTTLS (rfc2487) in php 5.1.0+
 153          * http://www.php.net/stream-socket-enable-crypto
 154          */
 155         if ($use_smtp_tls === 2) {
 156             if (function_exists('stream_socket_enable_crypto')) {
 157                 // don't try starting tls, when client thinks that it is already active
 158                 if ($this->tls_enabled) {
 159                     $this->dlv_msg = _("TLS session is already activated.");
 160                     return 0;
 161                 } elseif (!array_key_exists('STARTTLS',$this->ehlo)) {
 162                     // check for starttls in ehlo response
 163                     $this->dlv_msg = _("SMTP STARTTLS is enabled in SquirrelMail configuration, but used SMTP server does not support it");
 164                     return 0;
 165                 }
 166
 167                 // issue starttls command
 168                 fputs($stream, "STARTTLS\r\n");
 169                 // get response
 170                 $tmp = fgets($stream,1024);
 171                 if ($this->errorCheck($tmp,$stream)) {
 172                     return 0;
 173                 }
 174
 175                 // start crypto on connection. suppress function errors.
 176                 if (@stream_socket_enable_crypto($stream,true,STREAM_CRYPTO_METHOD_TLS_CLIENT)) {
 177                     // starttls was successful (rfc2487 5.2 Result of the STARTTLS Command)
 178                     // get new EHLO response
 179                     fputs($stream, "EHLO $helohost\r\n");
 180                     // Read ehlo response
 181                     $tmp = $this->parse_ehlo_response($stream);
 182                     if ($this->errorCheck($tmp,$stream)) {
 183                         // don't revert to helo here. server must support ESMTP
 184                         return 0;
 185                     }
 186                     // set information about started tls
 187                     $this->tls_enabled = true;
 188                 } else {
 189                     /**
 190                      * stream_socket_enable_crypto() call failed.
 191                      */
 192                     $this->dlv_msg = _("Unable to start TLS.");
 193                     return 0;
 194                     // Bug: can't get error message. See comments in sqimap_create_stream().
 195                 }
 196             } else {
 197                 // php install does not support stream_socket_enable_crypto() function
 198                 $this->dlv_msg = _("SMTP STARTTLS is enabled in SquirrelMail configuration, but used PHP version does not support functions that allow to enable encryption on open socket.");
 199                 return 0;
 200             }
 201         }
 202
 203         // FIXME: check ehlo response before using authentication
 204         if (( $smtp_auth_mech == 'cram-md5') or ( $smtp_auth_mech == 'digest-md5' )) {
 205             // Doing some form of non-plain auth
 206             if ($smtp_auth_mech == 'cram-md5') {
 207                 fputs($stream, "AUTH CRAM-MD5\r\n");
 208             } elseif ($smtp_auth_mech == 'digest-md5') {
 209                 fputs($stream, "AUTH DIGEST-MD5\r\n");
 210             }
 211
 212             $tmp = fgets($stream,1024);
 213
 214             if ($this->errorCheck($tmp,$stream)) {
 215                 return(0);
 216             }
 217
 218             // At this point, $tmp should hold "334 <challenge string>"
 219             $chall = substr($tmp,4);
 220             // Depending on mechanism, generate response string
 221             if ($smtp_auth_mech == 'cram-md5') {
 222                 $response = cram_md5_response($user,$pass,$chall);
 223             } elseif ($smtp_auth_mech == 'digest-md5') {
 224                 $response = digest_md5_response($user,$pass,$chall,'smtp',$host);
 225             }
 226             fputs($stream, $response);
 227
 228             // Let's see what the server had to say about that
 229             $tmp = fgets($stream,1024);
 230             if ($this->errorCheck($tmp,$stream)) {
 231                 return(0);
 232             }
 233
 234             // CRAM-MD5 is done at this point.  If DIGEST-MD5, there's a bit more to go
 235             if ($smtp_auth_mech == 'digest-md5') {
 236                 // $tmp contains rspauth, but I don't store that yet. (No need yet)
 237                 fputs($stream,"\r\n");
 238                 $tmp = fgets($stream,1024);
 239
 240                 if ($this->errorCheck($tmp,$stream)) {
 241                 return(0);
 242                 }
 243             }
 244         // CRAM-MD5 and DIGEST-MD5 code ends here
 245         } elseif ($smtp_auth_mech == 'none') {
 246         // No auth at all, just send helo and then send the mail
 247         // We already said hi earlier, nothing more is needed.
 248         } elseif ($smtp_auth_mech == 'login') {
 249             // The LOGIN method
 250             fputs($stream, "AUTH LOGIN\r\n");
 251             $tmp = fgets($stream, 1024);
 252
 253             if ($this->errorCheck($tmp, $stream)) {
 254                 return(0);
 255             }
 256             fputs($stream, base64_encode ($user) . "\r\n");
 257             $tmp = fgets($stream, 1024);
 258             if ($this->errorCheck($tmp, $stream)) {
 259                 return(0);
 260             }
 261
 262             fputs($stream, base64_encode($pass) . "\r\n");
 263             $tmp = fgets($stream, 1024);
 264             if ($this->errorCheck($tmp, $stream)) {
 265                 return(0);
 266             }
 267         } elseif ($smtp_auth_mech == "plain") {
 268             /* SASL Plain */
 269             $auth = base64_encode("$user\0$user\0$pass");
 270
 271             $query = "AUTH PLAIN\r\n";
 272             fputs($stream, $query);
 273             $read=fgets($stream, 1024);
 274
 275             if (substr($read,0,3) == '334') { // OK so far..
 276                 fputs($stream, "$auth\r\n");
 277                 $read = fgets($stream, 1024);
 278             }
 279
 280             $results=explode(" ",$read,3);
 281             $response=$results[1];
 282             $message=$results[2];
 283         } else {
 284             /* Right here, they've reached an unsupported auth mechanism.
 285             This is the ugliest hack I've ever done, but it'll do till I can fix
 286             things up better tomorrow.  So tired... */
 287             if ($this->errorCheck("535 Unable to use this auth type",$stream)) {
 288                 return(0);
 289             }
 290         }
 291
 292         /* Ok, who is sending the message? */
 293         $fromaddress = ($from->mailbox && $from->host) ?
 294             $from->mailbox.'@'.$from->host : '';
 295         fputs($stream, 'MAIL FROM:<'.$fromaddress.">\r\n");
 296         $tmp = fgets($stream, 1024);
 297         if ($this->errorCheck($tmp, $stream)) {
 298             return(0);
 299         }
 300
 301         /* send who the recipients are */
 302         for ($i = 0, $cnt = count($to); $i < $cnt; $i++) {
 303             if (!$to[$i]->host) $to[$i]->host = $domain;
 304             if ($to[$i]->mailbox) {
 305                 fputs($stream, 'RCPT TO:<'.$to[$i]->mailbox.'@'.$to[$i]->host.">\r\n");
 306                 $tmp = fgets($stream, 1024);
 307                 if ($this->errorCheck($tmp, $stream)) {
 308                     return(0);
 309                 }
 310             }
 311         }
 312
 313         for ($i = 0, $cnt = count($cc); $i < $cnt; $i++) {
 314             if (!$cc[$i]->host) $cc[$i]->host = $domain;
 315             if ($cc[$i]->mailbox) {
 316                 fputs($stream, 'RCPT TO:<'.$cc[$i]->mailbox.'@'.$cc[$i]->host.">\r\n");
 317                 $tmp = fgets($stream, 1024);
 318                 if ($this->errorCheck($tmp, $stream)) {
 319                     return(0);
 320                 }
 321             }
 322         }
 323
 324         for ($i = 0, $cnt = count($bcc); $i < $cnt; $i++) {
 325             if (!$bcc[$i]->host) $bcc[$i]->host = $domain;
 326             if ($bcc[$i]->mailbox) {
 327                 fputs($stream, 'RCPT TO:<'.$bcc[$i]->mailbox.'@'.$bcc[$i]->host.">\r\n");
 328                 $tmp = fgets($stream, 1024);
 329                 if ($this->errorCheck($tmp, $stream)) {
 330                     return(0);
 331                 }
 332             }
 333         }
 334         /* Lets start sending the actual message */
 335         fputs($stream, "DATA\r\n");
 336         $tmp = fgets($stream, 1024);
 337         if ($this->errorCheck($tmp, $stream)) {
 338                 return(0);
 339         }
 340         return $stream;
 341     }
 342
 343     function finalizeStream($stream) {
 344         fputs($stream, "\r\n.\r\n"); /* end the DATA part */
 345         $tmp = fgets($stream, 1024);
 346         $this->errorCheck($tmp, $stream);
 347         if ($this->dlv_ret_nr != 250) {
 348                 return(0);
 349         }
 350         fputs($stream, "QUIT\r\n"); /* log off */
 351         fclose($stream);
 352         return true;
 353     }
 354
 355     /* check if an SMTP reply is an error and set an error message) */
 356     function errorCheck($line, $smtpConnection) {
 357
 358         $err_num = substr($line, 0, 3);
 359         $this->dlv_ret_nr = $err_num;
 360         $server_msg = substr($line, 4);
 361
 362         while(substr($line, 0, 4) == ($err_num.'-')) {
 363             $line = fgets($smtpConnection, 1024);
 364             $server_msg .= substr($line, 4);
 365         }
 366
 367         if ( ((int) $err_num{0}) < 4) {
 368             return false;
 369         }
 370
 371         switch ($err_num) {
 372         case '421': $message = _("Service not available, closing channel");
 373             break;
 374         case '432': $message = _("A password transition is needed");
 375             break;
 376         case '450': $message = _("Requested mail action not taken: mailbox unavailable");
 377             break;
 378         case '451': $message = _("Requested action aborted: error in processing");
 379             break;
 380         case '452': $message = _("Requested action not taken: insufficient system storage");
 381             break;
 382         case '454': $message = _("Temporary authentication failure");
 383             break;
 384         case '500': $message = _("Syntax error; command not recognized");
 385             break;
 386         case '501': $message = _("Syntax error in parameters or arguments");
 387             break;
 388         case '502': $message = _("Command not implemented");
 389             break;
 390         case '503': $message = _("Bad sequence of commands");
 391             break;
 392         case '504': $message = _("Command parameter not implemented");
 393             break;
 394         case '530': $message = _("Authentication required");
 395             break;
 396         case '534': $message = _("Authentication mechanism is too weak");
 397             break;
 398         case '535': $message = _("Authentication failed");
 399             break;
 400         case '538': $message = _("Encryption required for requested authentication mechanism");
 401             break;
 402         case '550': $message = _("Requested action not taken: mailbox unavailable");
 403             break;
 404         case '551': $message = _("User not local; please try forwarding");
 405             break;
 406         case '552': $message = _("Requested mail action aborted: exceeding storage allocation");
 407             break;
 408         case '553': $message = _("Requested action not taken: mailbox name not allowed");
 409             break;
 410         case '554': $message = _("Transaction failed");
 411             break;
 412         default:    $message = _("Unknown response");
 413             break;
 414         }
 415
 416         $this->dlv_msg = $message;
 417         $this->dlv_server_msg = $server_msg;
 418
 419         return true;
 420     }
 421
 422     function authPop($pop_server='', $pop_port='', $user, $pass) {
 423         if (!$pop_port) {
 424             $pop_port = 110;
 425         }
 426         if (!$pop_server) {
 427             $pop_server = 'localhost';
 428         }
 429         $popConnection = fsockopen($pop_server, $pop_port, $err_no, $err_str);
 430         if (!$popConnection) {
 431             error_log("Error connecting to POP Server ($pop_server:$pop_port)"
 432                 . " $err_no : $err_str");
 433         } else {
 434             $tmp = fgets($popConnection, 1024); /* banner */
 435             if (substr($tmp, 0, 3) != '+OK') {
 436                 return(0);
 437             }
 438             fputs($popConnection, "USER $user\r\n");
 439             $tmp = fgets($popConnection, 1024);
 440             if (substr($tmp, 0, 3) != '+OK') {
 441                 return(0);
 442             }
 443             fputs($popConnection, 'PASS ' . $pass . "\r\n");
 444             $tmp = fgets($popConnection, 1024);
 445             if (substr($tmp, 0, 3) != '+OK') {
 446                 return(0);
 447             }
 448             fputs($popConnection, "QUIT\r\n"); /* log off */
 449             fclose($popConnection);
 450         }
 451     }
 452
 453     /**
 454      * Parses ESMTP EHLO response (rfc1869)
 455      *
 456      * Reads SMTP response to EHLO command and fills class variables
 457      * (ehlo array and domain string). Returns last line.
 458      * @param stream $stream smtp connection stream.
 459      * @return string last ehlo line
 460      * @since 1.5.1
 461      */
 462     function parse_ehlo_response($stream) {
 463         // don't cache ehlo information
 464         $this->ehlo=array();
 465         $ret = '';
 466         $firstline = true;
 467         /**
 468          * ehlo mailclient.example.org
 469          * 250-mail.example.org
 470          * 250-PIPELINING
 471          * 250-SIZE 52428800
 472          * 250-DATAZ
 473          * 250-STARTTLS
 474          * 250-AUTH LOGIN PLAIN
 475          * 250 8BITMIME
 476          */
 477         while ($line=fgets($stream, 1024)){
 478             // match[1] = first symbol after 250
 479             // match[2] = domain or ehlo-keyword
 480             // match[3] = greeting or ehlo-param
 481             // match space after keyword in ehlo-keyword CR LF
 482             if (preg_match("/^250(-|\s)(\S*)\s+(\S.*)\r\n/",$line,$match)||
 483                 preg_match("/^250(-|\s)(\S*)\s*\r\n/",$line,$match)) {
 484                 if ($firstline) {
 485                     // first ehlo line (250[-\ ]domain SP greeting)
 486                     $this->domain = $match[2];
 487                     $firstline=false;
 488                 } elseif (!isset($match[3])) {
 489                     // simple one word extension
 490                     $this->ehlo[strtoupper($match[2])]='';
 491                 } elseif (!preg_match("/\s/",trim($match[3]))) {
 492                     // extension with one option
 493                     // yes, I know about ctype extension. no, i don't want to depend on it
 494                     $this->ehlo[strtoupper($match[2])]=trim($match[3]);
 495                 } else {
 496                     // ehlo-param with spaces
 497                     $this->ehlo[strtoupper($match[2])]=explode(' ',trim($match[3]));
 498                 }
 499                 if ($match[1]==' ') {
 500                     // stop while cycle, if we reach last 250 line
 501                     $ret = $line;
 502                     break;
 503                 }
 504             } else {
 505                 // this is not 250 response
 506                 $ret = $line;
 507                 break;
 508             }
 509         }
 510         return $ret;
 511     }
 512 }
 513
 514 ?>