class/deliver/Deliver.class.php

   1 <?php
   2
   3 /**
   4  * Deliver.class.php
   5  *
   6  * This contains all the functions needed to send messages through
   7  * a delivery backend.
   8  *
   9  * @author Marc Groot Koerkamp
  10  * @copyright &copy; 1999-2007 The SquirrelMail Project Team
  11  * @license http://opensource.org/licenses/gpl-license.php GNU Public License
  12  * @version $Id$
  13  * @package squirrelmail
  14  */
  15
  16 /**
  17  * Deliver Class - called to actually deliver the message
  18  *
  19  * This class is called by compose.php and other code that needs
  20  * to send messages.  All delivery functionality should be centralized
  21  * in this class.
  22  *
  23  * Do not place UI code in this class, as UI code should be placed in templates
  24  * going forward.
  25  *
  26  * @author  Marc Groot Koerkamp
  27  * @package squirrelmail
  28  */
  29 class Deliver {
  30
  31     /**
  32      * function mail - send the message parts to the SMTP stream
  33      *
  34      * @param Message  $message      Message object to send
  35      * @param resource $stream       Handle to the SMTP stream
  36      * @param string   $reply_id     Identifies message being replied to
  37      *                               (OPTIONAL; caller should ONLY specify
  38      *                               a value for this when the message
  39      *                               being sent is a reply)
  40      * @param string   $reply_ent_id Identifies message being replied to
  41      *                               in the case it was an embedded/attached
  42      *                               message inside another (OPTIONAL; caller
  43      *                               should ONLY specify a value for this
  44      *                               when the message being sent is a reply)
  45      *
  46      * @return integer $raw_length
  47      */
  48     function mail($message, $stream=false, $reply_id=0, $reply_ent_id=0) {
  49         $rfc822_header = $message->rfc822_header;
  50         if (count($message->entities)) {
  51             $boundary = $this->mimeBoundary();
  52             $rfc822_header->content_type->properties['boundary']='"'.$boundary.'"';
  53         } else {
  54             $boundary='';
  55         }
  56         $raw_length = 0;
  57
  58
  59         // calculate reply header if needed
  60         //
  61         if ($reply_id) {
  62             global $imapConnection, $username, $imapServerAddress,
  63                    $imapPort, $mailbox;
  64             if (!$imapConnection)
  65                 $imapConnection = sqimap_login($username, FALSE,
  66                                                $imapServerAddress, $imapPort, 0);
  67
  68             sqimap_mailbox_select($imapConnection, $mailbox);
  69             $reply_message = sqimap_get_message($imapConnection, $reply_id, $mailbox);
  70
  71             if ($reply_ent_id) {
  72                 /* redefine the messsage in case of message/rfc822 */
  73                 $reply_message = $message->getEntity($reply_ent_id);
  74                 /* message is an entity which contains the envelope and type0=message
  75                  * and type1=rfc822. The actual entities are childs from
  76                  * $reply_message->entities[0]. That's where the encoding and is located
  77                  */
  78
  79                 $orig_header = $reply_message->rfc822_header; /* here is the envelope located */
  80
  81             } else {
  82                 $orig_header = $reply_message->rfc822_header;
  83             }
  84         }
  85         $message->reply_rfc822_header = $orig_header;
  86
  87
  88         $reply_rfc822_header = (isset($message->reply_rfc822_header)
  89                              ? $message->reply_rfc822_header : '');
  90         $header = $this->prepareRFC822_Header($rfc822_header, $reply_rfc822_header, $raw_length);
  91
  92         if ($stream) {
  93             $this->preWriteToStream($header);
  94             $this->writeToStream($stream, $header);
  95         }
  96         $this->writeBody($message, $stream, $raw_length, $boundary);
  97         return $raw_length;
  98     }
  99
 100     /**
 101      * function writeBody - generate and write the mime boundaries around each part to the stream
 102      *
 103      * Recursively formats and writes the MIME boundaries of the $message
 104      * to the output stream.
 105      *
 106      * @param Message   $message      Message object to transform
 107      * @param resource  $stream       SMTP output stream
 108      * @param integer  &$length_raw   raw length of the message (part)
 109      *                                as returned by mail fn
 110      * @param string    $boundary     custom boundary to call, usually for subparts
 111      *
 112      * @return void
 113      */
 114     function writeBody($message, $stream, &$length_raw, $boundary='') {
 115         // calculate boundary in case of multidimensional mime structures
 116         if ($boundary && $message->entity_id && count($message->entities)) {
 117             if (strpos($boundary,'_part_')) {
 118                 $boundary = substr($boundary,0,strpos($boundary,'_part_'));
 119
 120             // the next four lines use strrev to reverse any nested boundaries
 121             // because RFC 2046 (5.1.1) says that if a line starts with the outer
 122             // boundary string (doesn't matter what the line ends with), that
 123             // can be considered a match for the outer boundary; thus the nested
 124             // boundary needs to be unique from the outer one
 125             //
 126             } else if (strpos($boundary,'_trap_')) {
 127                 $boundary = substr(strrev($boundary),0,strpos(strrev($boundary),'_part_'));
 128             }
 129             $boundary_new = strrev($boundary . '_part_'.$message->entity_id);
 130         } else {
 131             $boundary_new = $boundary;
 132         }
 133         if ($boundary && !$message->rfc822_header) {
 134             $s = '--'.$boundary."\r\n";
 135             $s .= $this->prepareMIME_Header($message, $boundary_new);
 136             $length_raw += strlen($s);
 137             if ($stream) {
 138                 $this->preWriteToStream($s);
 139                 $this->writeToStream($stream, $s);
 140             }
 141         }
 142         $this->writeBodyPart($message, $stream, $length_raw);
 143
 144         $last = false;
 145         for ($i=0, $entCount=count($message->entities);$i<$entCount;$i++) {
 146             $msg = $this->writeBody($message->entities[$i], $stream, $length_raw, $boundary_new);
 147             if ($i == $entCount-1) $last = true;
 148         }
 149         if ($boundary && $last) {
 150             $s = "--".$boundary_new."--\r\n\r\n";
 151             $length_raw += strlen($s);
 152             if ($stream) {
 153                 $this->preWriteToStream($s);
 154                 $this->writeToStream($stream, $s);
 155             }
 156         }
 157     }
 158
 159     /**
 160      * function writeBodyPart - write each individual mimepart
 161      *
 162      * Recursively called by WriteBody to write each mime part to the SMTP stream
 163      *
 164      * @param Message   $message      Message object to transform
 165      * @param resource  $stream       SMTP output stream
 166      * @param integer  &$length       length of the message part
 167      *                                as returned by mail fn
 168      *
 169      * @return void
 170      */
 171     function writeBodyPart($message, $stream, &$length) {
 172         if ($message->mime_header) {
 173             $type0 = $message->mime_header->type0;
 174         } else {
 175             $type0 = $message->rfc822_header->content_type->type0;
 176         }
 177
 178         $body_part_trailing = $last = '';
 179         switch ($type0)
 180         {
 181         case 'text':
 182         case 'message':
 183             if ($message->body_part) {
 184                 $body_part = $message->body_part;
 185                 // remove NUL characters
 186                 $body_part = str_replace("\0",'',$body_part);
 187                 $length += $this->clean_crlf($body_part);
 188                 if ($stream) {
 189                     $this->preWriteToStream($body_part);
 190                     $this->writeToStream($stream, $body_part);
 191                 }
 192                 $last = $body_part;
 193             } elseif ($message->att_local_name) {
 194                 global $username, $attachment_dir;
 195                 $hashed_attachment_dir = getHashedDir($username, $attachment_dir);
 196                 $filename = $message->att_local_name;
 197                 $file = fopen ($hashed_attachment_dir . '/' . $filename, 'rb');
 198                 while ($body_part = fgets($file, 4096)) {
 199                     // remove NUL characters
 200                     $body_part = str_replace("\0",'',$body_part);
 201                     $length += $this->clean_crlf($body_part);
 202                     if ($stream) {
 203                         $this->preWriteToStream($body_part);
 204                         $this->writeToStream($stream, $body_part);
 205                     }
 206                     $last = $body_part;
 207                 }
 208                 fclose($file);
 209             }
 210             break;
 211         default:
 212             if ($message->body_part) {
 213                 $body_part = $message->body_part;
 214                 // remove NUL characters
 215                 $body_part = str_replace("\0",'',$body_part);
 216                 $length += $this->clean_crlf($body_part);
 217                 if ($stream) {
 218                     $this->writeToStream($stream, $body_part);
 219                 }
 220             } elseif ($message->att_local_name) {
 221                 global $username, $attachment_dir;
 222                 $hashed_attachment_dir = getHashedDir($username, $attachment_dir);
 223                 $filename = $message->att_local_name;
 224                 $file = fopen ($hashed_attachment_dir . '/' . $filename, 'rb');
 225                 while ($tmp = fread($file, 570)) {
 226                     $body_part = chunk_split(base64_encode($tmp));
 227                     // Up to 4.3.10 chunk_split always appends a newline,
 228                     // while in 4.3.11 it doesn't if the string to split
 229                     // is shorter than the chunk length.
 230                     if( substr($body_part, -1 , 1 ) != "\n" )
 231                         $body_part .= "\n";
 232                     $length += $this->clean_crlf($body_part);
 233                     if ($stream) {
 234                         $this->writeToStream($stream, $body_part);
 235                     }
 236                 }
 237                 fclose($file);
 238             }
 239             break;
 240         }
 241         $body_part_trailing = '';
 242         if ($last && substr($last,-1) != "\n") {
 243             $body_part_trailing = "\r\n";
 244         }
 245         if ($body_part_trailing) {
 246             $length += strlen($body_part_trailing);
 247             if ($stream) {
 248                 $this->preWriteToStream($body_part_trailing);
 249                 $this->writeToStream($stream, $body_part_trailing);
 250             }
 251         }
 252     }
 253
 254     /**
 255      * function clean_crlf - change linefeeds and newlines to legal characters
 256      *
 257      * The SMTP format only allows CRLF as line terminators.
 258      * This function replaces illegal teminators with the correct terminator.
 259      *
 260      * @param string &$s string to clean linefeeds on
 261      *
 262      * @return void
 263      */
 264     function clean_crlf(&$s) {
 265         $s = str_replace("\r\n", "\n", $s);
 266         $s = str_replace("\r", "\n", $s);
 267         $s = str_replace("\n", "\r\n", $s);
 268         return strlen($s);
 269     }
 270
 271     /**
 272      * function strip_crlf - strip linefeeds and newlines from a string
 273      *
 274      * The SMTP format only allows CRLF as line terminators.
 275      * This function strips all line terminators from the string.
 276      *
 277      * @param string &$s string to clean linefeeds on
 278      *
 279      * @return void
 280      */
 281     function strip_crlf(&$s) {
 282         $s = str_replace("\r\n ", '', $s);
 283         $s = str_replace("\r", '', $s);
 284         $s = str_replace("\n", '', $s);
 285     }
 286
 287     /**
 288      * function preWriteToStream - reserved for extended functionality
 289      *
 290      * This function is not yet implemented.
 291      * Reserved for extended functionality.
 292      *
 293      * @param string &$s string to operate on
 294      *
 295      * @return void
 296      */
 297     function preWriteToStream(&$s) {
 298     }
 299
 300     /**
 301      * function writeToStream - write data to the SMTP stream
 302      *
 303      * @param resource $stream  SMTP output stream
 304      * @param string   $data    string with data to send to the SMTP stream
 305      *
 306      * @return void
 307      */
 308     function writeToStream($stream, $data) {
 309         fputs($stream, $data);
 310     }
 311
 312     /**
 313      * function initStream - reserved for extended functionality
 314      *
 315      * This function is not yet implemented.
 316      * Reserved for extended functionality.
 317      *
 318      * @param Message $message  Message object
 319      * @param string  $host     host name or IP to connect to
 320      * @param string  $user     username to log into the SMTP server with
 321      * @param string  $pass     password to log into the SMTP server with
 322      * @param integer $length
 323      *
 324      * @return handle $stream file handle resource to SMTP stream
 325      */
 326     function initStream($message, $length=0, $host='', $port='', $user='', $pass='') {
 327         return $stream;
 328     }
 329
 330     /**
 331      * function getBCC - reserved for extended functionality
 332      *
 333      * This function is not yet implemented.
 334      * Reserved for extended functionality.
 335      *
 336      */
 337     function getBCC() {
 338         return false;
 339     }
 340
 341     /**
 342      * function prepareMIME_Header - creates the mime header
 343      *
 344      * @param Message $message  Message object to act on
 345      * @param string  $boundary mime boundary from fn MimeBoundary
 346      *
 347      * @return string $header properly formatted mime header
 348      */
 349     function prepareMIME_Header($message, $boundary) {
 350         $mime_header = $message->mime_header;
 351         $rn="\r\n";
 352         $header = array();
 353
 354         $contenttype = 'Content-Type: '. $mime_header->type0 .'/'.
 355                         $mime_header->type1;
 356         if (count($message->entities)) {
 357             $contenttype .= ';' . 'boundary="'.$boundary.'"';
 358         }
 359         if (isset($mime_header->parameters['name'])) {
 360             $contenttype .= '; name="'.
 361             encodeHeader($mime_header->parameters['name']). '"';
 362         }
 363         if (isset($mime_header->parameters['charset'])) {
 364             $charset = $mime_header->parameters['charset'];
 365             $contenttype .= '; charset="'.
 366             encodeHeader($charset). '"';
 367         }
 368
 369         $header[] = $contenttype . $rn;
 370         if ($mime_header->description) {
 371             $header[] = 'Content-Description: ' . $mime_header->description . $rn;
 372         }
 373         if ($mime_header->encoding) {
 374             $header[] = 'Content-Transfer-Encoding: ' . $mime_header->encoding . $rn;
 375         } else {
 376             if ($mime_header->type0 == 'text' || $mime_header->type0 == 'message') {
 377                 $header[] = 'Content-Transfer-Encoding: 8bit' .  $rn;
 378             } else {
 379                 $header[] = 'Content-Transfer-Encoding: base64' .  $rn;
 380             }
 381         }
 382         if ($mime_header->id) {
 383             $header[] = 'Content-ID: ' . $mime_header->id . $rn;
 384         }
 385         if ($mime_header->disposition) {
 386             $disposition = $mime_header->disposition;
 387             $contentdisp = 'Content-Disposition: ' . $disposition->name;
 388             if ($disposition->getProperty('filename')) {
 389                 $contentdisp .= '; filename="'.
 390                 encodeHeader($disposition->getProperty('filename')). '"';
 391             }
 392             $header[] = $contentdisp . $rn;
 393         }
 394         if ($mime_header->md5) {
 395             $header[] = 'Content-MD5: ' . $mime_header->md5 . $rn;
 396         }
 397         if ($mime_header->language) {
 398             $header[] = 'Content-Language: ' . $mime_header->language . $rn;
 399         }
 400
 401         $cnt = count($header);
 402         $hdr_s = '';
 403         for ($i = 0 ; $i < $cnt ; $i++)    {
 404             $hdr_s .= $this->foldLine($header[$i], 78,str_pad('',4));
 405         }
 406         $header = $hdr_s;
 407         $header .= $rn; /* One blank line to separate mimeheader and body-entity */
 408         return $header;
 409     }
 410
 411     /**
 412      * function prepareRFC822_Header - prepares the RFC822 header string from Rfc822Header object(s)
 413      *
 414      * This function takes the Rfc822Header object(s) and formats them
 415      * into the RFC822Header string to send to the SMTP server as part
 416      * of the SMTP message.
 417      *
 418      * @param Rfc822Header  $rfc822_header
 419      * @param Rfc822Header  $reply_rfc822_header
 420      * @param integer      &$raw_length length of the message
 421      *
 422      * @return string $header
 423      */
 424     function prepareRFC822_Header($rfc822_header, $reply_rfc822_header, &$raw_length) {
 425         global $domain, $username, $encode_header_key,
 426                $edit_identity, $hide_auth_header;
 427
 428         /* if server var SERVER_NAME not available, use $domain */
 429         if(!sqGetGlobalVar('SERVER_NAME', $SERVER_NAME, SQ_SERVER)) {
 430             $SERVER_NAME = $domain;
 431         }
 432
 433         sqGetGlobalVar('REMOTE_ADDR', $REMOTE_ADDR, SQ_SERVER);
 434         sqGetGlobalVar('REMOTE_PORT', $REMOTE_PORT, SQ_SERVER);
 435         sqGetGlobalVar('REMOTE_HOST', $REMOTE_HOST, SQ_SERVER);
 436         sqGetGlobalVar('HTTP_VIA',    $HTTP_VIA,    SQ_SERVER);
 437         sqGetGlobalVar('HTTP_X_FORWARDED_FOR', $HTTP_X_FORWARDED_FOR, SQ_SERVER);
 438
 439         $rn = "\r\n";
 440
 441         /* This creates an RFC 822 date */
 442         $date = date('D, j M Y H:i:s ', time()) . $this->timezone();
 443         /* Create a message-id */
 444         $message_id = '<' . $REMOTE_PORT . '.';
 445         if (isset($encode_header_key) && trim($encode_header_key)!='') {
 446             // use encrypted form of remote address
 447             $message_id.= OneTimePadEncrypt($this->ip2hex($REMOTE_ADDR),base64_encode($encode_header_key));
 448         } else {
 449             $message_id.= $REMOTE_ADDR;
 450         }
 451         $message_id .= '.' . time() . '.squirrel@' . $SERVER_NAME .'>';
 452         /* Make an RFC822 Received: line */
 453         if (isset($REMOTE_HOST)) {
 454             $received_from = "$REMOTE_HOST ([$REMOTE_ADDR])";
 455         } else {
 456             $received_from = $REMOTE_ADDR;
 457         }
 458         if (isset($HTTP_VIA) || isset ($HTTP_X_FORWARDED_FOR)) {
 459             if (!isset($HTTP_X_FORWARDED_FOR) || $HTTP_X_FORWARDED_FOR == '') {
 460                 $HTTP_X_FORWARDED_FOR = 'unknown';
 461             }
 462             $received_from .= " (proxying for $HTTP_X_FORWARDED_FOR)";
 463         }
 464         $header = array();
 465
 466         /**
 467          * SquirrelMail header
 468          *
 469          * This Received: header provides information that allows to track
 470          * user and machine that was used to send email. Don't remove it
 471          * unless you understand all possible forging issues or your
 472          * webmail installation does not prevent changes in user's email address.
 473          * See SquirrelMail bug tracker #847107 for more details about it.
 474          *
 475          * Add $hide_squirrelmail_header as a candidate for config_local.php
 476          * to allow completely hiding SquirrelMail participation in message
 477          * processing; This is dangerous, especially if users can modify their
 478          * account information, as it makes mapping a sent message back to the
 479          * original sender almost impossible.
 480          */
 481         $show_sm_header = ( defined('hide_squirrelmail_header') ? ! hide_squirrelmail_header : 1 );
 482
 483         if ( $show_sm_header ) {
 484           if (isset($encode_header_key) &&
 485             trim($encode_header_key)!='') {
 486             // use encoded headers, if encryption key is set and not empty
 487             $header[] = 'X-Squirrel-UserHash: '.OneTimePadEncrypt($username,base64_encode($encode_header_key)).$rn;
 488             $header[] = 'X-Squirrel-FromHash: '.OneTimePadEncrypt($this->ip2hex($REMOTE_ADDR),base64_encode($encode_header_key)).$rn;
 489             if (isset($HTTP_X_FORWARDED_FOR))
 490                 $header[] = 'X-Squirrel-ProxyHash:'.OneTimePadEncrypt($this->ip2hex($HTTP_X_FORWARDED_FOR),base64_encode($encode_header_key)).$rn;
 491           } else {
 492             // use default received headers
 493             $header[] = "Received: from $received_from" . $rn;
 494             if ($edit_identity || ! isset($hide_auth_header) || ! $hide_auth_header)
 495                 $header[] = "        (SquirrelMail authenticated user $username)" . $rn;
 496             $header[] = "        by $SERVER_NAME with HTTP;" . $rn;
 497             $header[] = "        $date" . $rn;
 498           }
 499         }
 500
 501         /* Insert the rest of the header fields */
 502         $header[] = 'Message-ID: '. $message_id . $rn;
 503         if (is_object($reply_rfc822_header) &&
 504             isset($reply_rfc822_header->message_id) &&
 505             $reply_rfc822_header->message_id) {
 506             $rep_message_id = $reply_rfc822_header->message_id;
 507         //        $this->strip_crlf($message_id);
 508             $header[] = 'In-Reply-To: '.$rep_message_id . $rn;
 509             $references = $this->calculate_references($reply_rfc822_header);
 510             $header[] = 'References: '.$references . $rn;
 511         }
 512         $header[] = "Date: $date" . $rn;
 513         $header[] = 'Subject: '.encodeHeader($rfc822_header->subject) . $rn;
 514         $header[] = 'From: '. $rfc822_header->getAddr_s('from',",$rn ",true) . $rn;
 515
 516         // folding address list [From|To|Cc|Bcc] happens by using ",$rn<space>"
 517         // as delimiter
 518         // Do not use foldLine for that.
 519
 520         // RFC2822 if from contains more then 1 address
 521         if (count($rfc822_header->from) > 1) {
 522             $header[] = 'Sender: '. $rfc822_header->getAddr_s('sender',',',true) . $rn;
 523         }
 524         if (count($rfc822_header->to)) {
 525             $header[] = 'To: '. $rfc822_header->getAddr_s('to',",$rn ",true) . $rn;
 526         }
 527         if (count($rfc822_header->cc)) {
 528             $header[] = 'Cc: '. $rfc822_header->getAddr_s('cc',",$rn ",true) . $rn;
 529         }
 530         if (count($rfc822_header->reply_to)) {
 531             $header[] = 'Reply-To: '. $rfc822_header->getAddr_s('reply_to',',',true) . $rn;
 532         }
 533         /* Sendmail should return true. Default = false */
 534         $bcc = $this->getBcc();
 535         if (count($rfc822_header->bcc)) {
 536             $s = 'Bcc: '. $rfc822_header->getAddr_s('bcc',",$rn ",true) . $rn;
 537             if (!$bcc) {
 538                 $raw_length += strlen($s);
 539             } else {
 540                 $header[] = $s;
 541             }
 542         }
 543         /* Identify SquirrelMail */
 544         $header[] = 'User-Agent: SquirrelMail/' . SM_VERSION . $rn;
 545         /* Do the MIME-stuff */
 546         $header[] = 'MIME-Version: 1.0' . $rn;
 547         $contenttype = 'Content-Type: '. $rfc822_header->content_type->type0 .'/'.
 548                                          $rfc822_header->content_type->type1;
 549         if (count($rfc822_header->content_type->properties)) {
 550             foreach ($rfc822_header->content_type->properties as $k => $v) {
 551                 if ($k && $v) {
 552                     $contenttype .= ';' .$k.'='.$v;
 553                 }
 554             }
 555         }
 556         $header[] = $contenttype . $rn;
 557         if ($encoding = $rfc822_header->encoding) {
 558             $header[] = 'Content-Transfer-Encoding: ' . $encoding .  $rn;
 559         }
 560         if (isset($rfc822_header->dnt) && $rfc822_header->dnt) {
 561             $dnt = $rfc822_header->getAddr_s('dnt');
 562             /* Pegasus Mail */
 563             $header[] = 'X-Confirm-Reading-To: '.$dnt. $rn;
 564             /* RFC 2298 */
 565             $header[] = 'Disposition-Notification-To: '.$dnt. $rn;
 566         }
 567         if ($rfc822_header->priority) {
 568             switch($rfc822_header->priority)
 569             {
 570             case 1:
 571                 $header[] = 'X-Priority: 1 (Highest)'.$rn;
 572                 $header[] = 'Importance: High'. $rn; break;
 573             case 5:
 574                 $header[] = 'X-Priority: 5 (Lowest)'.$rn;
 575                 $header[] = 'Importance: Low'. $rn; break;
 576             default: break;
 577             }
 578         }
 579         /* Insert headers from the $more_headers array */
 580         if(count($rfc822_header->more_headers)) {
 581             reset($rfc822_header->more_headers);
 582             foreach ($rfc822_header->more_headers as $k => $v) {
 583                 $header[] = $k.': '.$v .$rn;
 584             }
 585         }
 586         $cnt = count($header);
 587         $hdr_s = '';
 588
 589         for ($i = 0 ; $i < $cnt ; $i++) {
 590             $sKey = substr($header[$i],0,strpos($header[$i],':'));
 591             switch ($sKey)
 592             {
 593             case 'Message-ID':
 594             case 'In-Reply_To':
 595                 $hdr_s .= $header[$i];
 596                 break;
 597             case 'References':
 598                 $sRefs = substr($header[$i],12);
 599                 $aRefs = explode(' ',$sRefs);
 600                 $sLine = 'References:';
 601                 foreach ($aRefs as $sReference) {
 602                     if ( trim($sReference) == '' ) {
 603                          /* Don't add spaces. */
 604                     } elseif (strlen($sLine)+strlen($sReference) >76) {
 605                         $hdr_s .= $sLine;
 606                         $sLine = $rn . '    ' . $sReference;
 607                     } else {
 608                         $sLine .= ' '. $sReference;
 609                     }
 610                 }
 611                 $hdr_s .= $sLine;
 612                 break;
 613             case 'To':
 614             case 'Cc':
 615             case 'Bcc':
 616             case 'From':
 617                 $hdr_s .= $header[$i];
 618                 break;
 619             default: $hdr_s .= $this->foldLine($header[$i], 78, str_pad('',4)); break;
 620             }
 621         }
 622         $header = $hdr_s;
 623         $header .= $rn; /* One blank line to separate header and body */
 624         $raw_length += strlen($header);
 625         return $header;
 626     }
 627
 628     /**
 629      * function foldLine - for cleanly folding of headerlines
 630      *
 631      * @param   string  $line
 632      * @param   integer $length length to fold the line at
 633      * @param   string  $pre    prefix the line with...
 634      *
 635      * @return string   $line folded line with trailing CRLF
 636      */
 637     function foldLine($line, $length, $pre='') {
 638         $line = substr($line,0, -2);
 639         $length -= 2; /* do not fold between \r and \n */
 640         $cnt = strlen($line);
 641         if ($cnt > $length) { /* try folding */
 642             $fold_string = "\r\n " . $pre;
 643             $bFirstFold = false;
 644             $aFoldLine = array();
 645             while (strlen($line) > $length) {
 646                 $fold = false;
 647                 /* handle encoded parts */
 648                 if (preg_match('/(=\?([^?]*)\?(Q|B)\?([^?]*)\?=)(\s+|.*)/Ui',$line,$regs)) {
 649                     $fold_tmp = $regs[1];
 650                     if (!trim($regs[5])) {
 651                         $fold_tmp .= $regs[5];
 652                     }
 653                     $iPosEnc = strpos($line,$fold_tmp);
 654                     $iLengthEnc = strlen($fold_tmp);
 655                     $iPosEncEnd = $iPosEnc+$iLengthEnc;
 656                     if ($iPosEnc < $length && (($iPosEncEnd) > $length)) {
 657                         $fold = true;
 658                         /* fold just before the start of the encoded string */
 659                         if ($iPosEnc) {
 660                             $aFoldLine[] = substr($line,0,$iPosEnc);
 661                         }
 662                         $line = substr($line,$iPosEnc);
 663                         if (!$bFirstFold) {
 664                             $bFirstFold = true;
 665                             $length -= strlen($fold_string);
 666                         }
 667                         if ($iLengthEnc > $length) { /* place the encoded
 668                             string on a separate line and do not fold inside it*/
 669                             /* minimize foldstring */
 670                             $fold_string = "\r\n ";
 671                             $aFoldLine[] = substr($line,0,$iLengthEnc);
 672                             $line = substr($line,$iLengthEnc);
 673                         }
 674                     } else if ($iPosEnc < $length) { /* the encoded string fits into the foldlength */
 675                         /*remainder */
 676                         $sLineRem = substr($line,$iPosEncEnd,$length - $iPosEncEnd);
 677                         if (preg_match('/^(=\?([^?]*)\?(Q|B)\?([^?]*)\?=)(.*)/Ui',$sLineRem) || !preg_match('/[=,;\s]/',$sLineRem)) {
 678                             /*impossible to fold clean in the next part -> fold after the enc string */
 679                             $aFoldLine[] = substr($line,0,$iPosEncEnd);
 680                             $line = substr($line,$iPosEncEnd);
 681                             $fold = true;
 682                             if (!$bFirstFold) {
 683                                 $bFirstFold = true;
 684                                 $length -= strlen($fold_string);
 685                             }
 686                         }
 687                     }
 688                 }
 689                 if (!$fold) {
 690                     $line_tmp = substr($line,0,$length);
 691                     $iFoldPos = false;
 692                     /* try to fold at logical places */
 693                     switch (true)
 694                     {
 695                     case ($iFoldPos = strrpos($line_tmp,',')): break;
 696                     case ($iFoldPos = strrpos($line_tmp,';')): break;
 697                     case ($iFoldPos = strrpos($line_tmp,' ')): break;
 698                     case ($iFoldPos = strrpos($line_tmp,'=')): break;
 699                     default: break;
 700                     }
 701
 702                     if (!$iFoldPos) { /* clean folding didn't work */
 703                         $iFoldPos = $length;
 704                     }
 705                     $aFoldLine[] = substr($line,0,$iFoldPos+1);
 706                     $line = substr($line,$iFoldPos+1);
 707                     if (!$bFirstFold) {
 708                         $bFirstFold = true;
 709                         $length -= strlen($fold_string);
 710                     }
 711                 }
 712             }
 713             /*$reconstruct the line */
 714             if ($line) {
 715                 $aFoldLine[] = $line;
 716             }
 717             $line = implode($fold_string,$aFoldLine);
 718         }
 719         return $line."\r\n";
 720     }
 721
 722     /**
 723      * function mimeBoundary - calculates the mime boundary to use
 724      *
 725      * This function will generate a random mime boundary base part
 726      * for the message if the boundary has not already been set.
 727      *
 728      * @return string $mimeBoundaryString random mime boundary string
 729      */
 730     function mimeBoundary () {
 731         static $mimeBoundaryString;
 732
 733         if ( !isset( $mimeBoundaryString ) ||
 734             $mimeBoundaryString == '') {
 735             $mimeBoundaryString = '----=_' . date( 'YmdHis' ) . '_' .
 736             mt_rand( 10000, 99999 );
 737         }
 738         return $mimeBoundaryString;
 739     }
 740
 741     /**
 742      * function timezone - Time offset for correct timezone
 743      *
 744      * @return string $result with timezone and offset
 745      */
 746     function timezone () {
 747         global $invert_time;
 748
 749         $diff_second = date('Z');
 750         if ($invert_time) {
 751             $diff_second = - $diff_second;
 752         }
 753         if ($diff_second > 0) {
 754             $sign = '+';
 755         } else {
 756             $sign = '-';
 757         }
 758         $diff_second = abs($diff_second);
 759         $diff_hour = floor ($diff_second / 3600);
 760         $diff_minute = floor (($diff_second-3600*$diff_hour) / 60);
 761         $zonename = '('.strftime('%Z').')';
 762         $result = sprintf ("%s%02d%02d %s", $sign, $diff_hour, $diff_minute,
 763                        $zonename);
 764         return ($result);
 765     }
 766
 767     /**
 768      * function calculate_references - calculate correct References string
 769      * Adds the current message ID, and makes sure it doesn't grow forever,
 770      * to that extent it drops message-ID's in a smart way until the string
 771      * length is under the recommended value of 1000 ("References: <986>\r\n").
 772      * It always keeps the first and the last three ID's.
 773      *
 774      * @param   Rfc822Header $hdr    message header to calculate from
 775      *
 776      * @return  string       $refer  concatenated and trimmed References string
 777      */
 778     function calculate_references($hdr) {
 779         $aReferences = preg_split('/\s+/', $hdr->references);
 780         $message_id = $hdr->message_id;
 781         $in_reply_to = $hdr->in_reply_to;
 782
 783         // if References already exists, add the current message ID at the end.
 784         // no References exists; if we know a IRT, add that aswell
 785         if (count($aReferences) == 0 && $in_reply_to) {
 786             $aReferences[] = $in_reply_to;
 787         }
 788         $aReferences[] = $message_id;
 789
 790         // sanitize the array: trim whitespace, remove dupes
 791         array_walk($aReferences, 'sq_trim_value');
 792         $aReferences = array_unique($aReferences);
 793
 794         while ( count($aReferences) > 4 && strlen(implode(' ', $aReferences)) >= 986 ) {
 795             $aReferences = array_merge(array_slice($aReferences,0,1),array_slice($aReferences,2));
 796         }
 797         return implode(' ', $aReferences);
 798     }
 799
 800     /**
 801      * Converts ip address to hexadecimal string
 802      *
 803      * Function is used to convert ipv4 and ipv6 addresses to hex strings.
 804      * It removes all delimiter symbols from ip addresses, converts decimal
 805      * ipv4 numbers to hex and pads strings in order to present full length
 806      * address. ipv4 addresses are represented as 8 byte strings, ipv6 addresses
 807      * are represented as 32 byte string.
 808      *
 809      * If function fails to detect address format, it returns unprocessed string.
 810      * @param string $string ip address string
 811      * @return string processed ip address string
 812      * @since 1.5.1 and 1.4.5
 813      */
 814     function ip2hex($string) {
 815         if (preg_match("/^(\d+)\.(\d+)\.(\d+)\.(\d+)$/",$string,$match)) {
 816             // ipv4 address
 817             $ret = str_pad(dechex($match[1]),2,'0',STR_PAD_LEFT)
 818                 . str_pad(dechex($match[2]),2,'0',STR_PAD_LEFT)
 819                 . str_pad(dechex($match[3]),2,'0',STR_PAD_LEFT)
 820                 . str_pad(dechex($match[4]),2,'0',STR_PAD_LEFT);
 821         } elseif (preg_match("/^([0-9a-h]+)\:([0-9a-h]+)\:([0-9a-h]+)\:([0-9a-h]+)\:([0-9a-h]+)\:([0-9a-h]+)\:([0-9a-h]+)\:([0-9a-h]+)$/i",$string,$match)) {
 822             // full ipv6 address
 823             $ret = str_pad($match[1],4,'0',STR_PAD_LEFT)
 824                 . str_pad($match[2],4,'0',STR_PAD_LEFT)
 825                 . str_pad($match[3],4,'0',STR_PAD_LEFT)
 826                 . str_pad($match[4],4,'0',STR_PAD_LEFT)
 827                 . str_pad($match[5],4,'0',STR_PAD_LEFT)
 828                 . str_pad($match[6],4,'0',STR_PAD_LEFT)
 829                 . str_pad($match[7],4,'0',STR_PAD_LEFT)
 830                 . str_pad($match[8],4,'0',STR_PAD_LEFT);
 831         } elseif (preg_match("/^\:\:([0-9a-h\:]+)$/i",$string,$match)) {
 832             // short ipv6 with all starting symbols nulled
 833             $aAddr=explode(':',$match[1]);
 834             $ret='';
 835             foreach ($aAddr as $addr) {
 836                 $ret.=str_pad($addr,4,'0',STR_PAD_LEFT);
 837             }
 838             $ret=str_pad($ret,32,'0',STR_PAD_LEFT);
 839         } elseif (preg_match("/^([0-9a-h\:]+)::([0-9a-h\:]+)$/i",$string,$match)) {
 840             // short ipv6 with middle part nulled
 841             $aStart=explode(':',$match[1]);
 842             $sStart='';
 843             foreach($aStart as $addr) {
 844                 $sStart.=str_pad($addr,4,'0',STR_PAD_LEFT);
 845             }
 846             $aEnd = explode(':',$match[2]);
 847             $sEnd='';
 848             foreach($aEnd as $addr) {
 849                 $sEnd.=str_pad($addr,4,'0',STR_PAD_LEFT);
 850             }
 851             $ret = $sStart
 852                 . str_pad('',(32 - strlen($sStart . $sEnd)),'0',STR_PAD_LEFT)
 853                 . $sEnd;
 854         } else {
 855             // unknown addressing
 856             $ret = $string;
 857         }
 858         return $ret;
 859     }
 860 }