functions/mime.php

   1 <?php
   2
   3 /**
   4  * mime.php
   5  *
   6  * Copyright (c) 1999-2002 The SquirrelMail Project Team
   7  * Licensed under the GNU GPL. For full terms see the file COPYING.
   8  *
   9  * This contains the functions necessary to detect and decode MIME
  10  * messages.
  11  *
  12  * $Id$
  13  */
  14
  15 require_once('../functions/imap.php');
  16 require_once('../functions/attachment_common.php');
  17
  18 /** Setting up the objects that have the structure for the message **/
  19 class msg_header {
  20     /** msg_header contains generic variables for values that **/
  21     /** could be in a header.                                 **/
  22
  23     var $type0 = '', $type1 = '', $boundary = '', $charset = '',
  24         $encoding = '', $size = 0, $to = array(), $from = '', $date = '',
  25         $cc = array(), $bcc = array(), $reply_to = '', $subject = '',
  26         $id = 0, $mailbox = '', $description = '', $filename = '',
  27         $entity_id = 0, $message_id = 0, $name = '', $priority = 3;
  28 }
  29
  30 class message {
  31     /** message is the object that contains messages.  It is a recursive
  32       object in that through the $entities variable, it can contain
  33       more objects of type message.  See documentation in mime.txt for
  34       a better description of how this works.
  35     **/
  36     var $header = '';
  37     var $entities = array();
  38
  39     function addEntity ($msg) {
  40         $this->entities[] = $msg;
  41     }
  42 }
  43
  44 /* --------------------------------------------------------------------------------- */
  45 /* MIME DECODING                                                                     */
  46 /* --------------------------------------------------------------------------------- */
  47
  48 /* This function gets the structure of a message and stores it in the "message" class.
  49  * It will return this object for use with all relevant header information and
  50  * fully parsed into the standard "message" object format.
  51  */
  52 function mime_structure ($imap_stream, $header) {
  53
  54     sqimap_messages_flag ($imap_stream, $header->id, $header->id, 'Seen');
  55     $ssid = sqimap_session_id();
  56     $lsid = strlen( $ssid );
  57     $id = $header->id;
  58     fputs ($imap_stream, "$ssid FETCH $id BODYSTRUCTURE\r\n");
  59     //
  60     // This should use sqimap_read_data instead of reading it itself
  61     //
  62     $read = fgets ($imap_stream, 10000);
  63     $bodystructure = '';
  64     while ( substr($read, 0, $lsid) <> $ssid &&
  65          !feof( $imap_stream ) ) {
  66         $bodystructure .= $read;
  67         $read = fgets ($imap_stream, 10000);
  68     }
  69     $read = $bodystructure;
  70
  71     // isolate the body structure and remove beginning and end parenthesis
  72     $read = trim(substr ($read, strpos(strtolower($read), 'bodystructure') + 13));
  73     $read = trim(substr ($read, 0, -1));
  74     $end = mime_match_parenthesis(0, $read);
  75     while ($end == strlen($read)-1) {
  76         $read = trim(substr ($read, 0, -1));
  77         $read = trim(substr ($read, 1));
  78         $end = mime_match_parenthesis(0, $read);
  79     }
  80
  81     $msg = mime_parse_structure ($read, 0);
  82     $msg->header = $header;
  83
  84     return( $msg );
  85 }
  86
  87 /* this starts the parsing of a particular structure.  It is called recursively,
  88  * so it can be passed different structures.  It returns an object of type
  89  * $message.
  90  * First, it checks to see if it is a multipart message.  If it is, then it
  91  * handles that as it sees is necessary.  If it is just a regular entity,
  92  * then it parses it and adds the necessary header information (by calling out
  93  * to mime_get_elements()
  94  */
  95 function mime_parse_structure ($structure, $ent_id) {
  96
  97   $msg = new message();
  98   if ($structure{0} == '(') {
  99      $ent_id = mime_new_element_level($ent_id);
 100      $start = $end = -1;
 101      do {
 102         $start = $end+1;
 103         $end = mime_match_parenthesis ($start, $structure);
 104
 105         $element = substr($structure, $start+1, ($end - $start)-1);
 106         $ent_id = mime_increment_id ($ent_id);
 107         $newmsg = mime_parse_structure ($element, $ent_id);
 108         $msg->addEntity ($newmsg);
 109      } while ($structure{$end+1} == '(');
 110   } else {
 111      // parse the elements
 112      $msg = mime_get_element ($structure, $msg, $ent_id);
 113   }
 114   return $msg;
 115 }
 116
 117 /* Increments the element ID.  An element id can look like any of
 118  * the following:  1, 1.2, 4.3.2.4.1, etc.  This function increments
 119  * the last number of the element id, changing 1.2 to 1.3.
 120  */
 121 function mime_increment_id ($id) {
 122
 123     if (strpos($id, ".")) {
 124         $first = substr($id, 0, strrpos($id, "."));
 125         $last = substr($id, strrpos($id, ".")+1);
 126         $last++;
 127         $new = $first . "." .$last;
 128     } else {
 129         $new = $id + 1;
 130     }
 131
 132     return $new;
 133 }
 134
 135 /*
 136  * See comment for mime_increment_id().
 137  * This adds another level on to the entity_id changing 1.3 to 1.3.0
 138  * NOTE:  1.3.0 is not a valid element ID.  It MUST be incremented
 139  *        before it can be used.  I left it this way so as not to have
 140  *        to make a special case if it is the first entity_id.  It
 141  *        always increments it, and that works fine.
 142  */
 143 function mime_new_element_level ($id) {
 144
 145   if (!$id) {
 146       $id = 0;
 147   } else {
 148       $id = $id . '.0';
 149   }
 150
 151   return( $id );
 152 }
 153
 154 function mime_get_element (&$structure, $msg, $ent_id) {
 155
 156   $elem_num = 1;
 157   $msg->header = new msg_header();
 158   $msg->header->entity_id = $ent_id;
 159   $properties = array();
 160
 161   while (strlen($structure) > 0) {
 162      $structure = trim($structure);
 163      $char = $structure{0};
 164
 165      if (strtolower(substr($structure, 0, 3)) == 'nil') {
 166         $text = '';
 167         $structure = substr($structure, 3);
 168      } else if ($char == '"') {
 169         // loop through until we find the matching quote, and return that as a string
 170         $pos = 1;
 171         $text = '';
 172         while ( ($char = $structure{$pos} ) <> '"' && $pos < strlen($structure)) {
 173            $text .= $char;
 174            $pos++;
 175         }
 176         $structure = substr($structure, strlen($text) + 2);
 177      } else if ($char == '(') {
 178         // comment me
 179         $end = mime_match_parenthesis (0, $structure);
 180         $sub = substr($structure, 1, $end-1);
 181         $properties = mime_get_props($properties, $sub);
 182         $structure = substr($structure, strlen($sub) + 2);
 183      } else {
 184         // loop through until we find a space or an end parenthesis
 185         $pos = 0;
 186         $char = $structure{$pos};
 187         $text = '';
 188         while ($char != ' ' && $char != ')' && $pos < strlen($structure)) {
 189            $text .= $char;
 190            $pos++;
 191            $char = $structure{$pos};
 192         }
 193         $structure = substr($structure, strlen($text));
 194      }
 195
 196      // This is where all the text parts get put into the header
 197      switch ($elem_num) {
 198         case 1:
 199            $msg->header->type0 = strtolower($text);
 200            break;
 201         case 2:
 202            $msg->header->type1 = strtolower($text);
 203            break;
 204         case 4: // Id
 205            // Invisimail enclose images with <>
 206            $msg->header->id = str_replace( '<', '', str_replace( '>', '', $text ) );
 207            break;
 208         case 5:
 209            $msg->header->description = $text;
 210            break;
 211         case 6:
 212            $msg->header->encoding = strtolower($text);
 213            break;
 214         case 7:
 215            $msg->header->size = $text;
 216            break;
 217         default:
 218            if ($msg->header->type0 == 'text' && $elem_num == 8) {
 219               // This is a plain text message, so lets get the number of lines
 220               // that it contains.
 221               $msg->header->num_lines = $text;
 222
 223            } else if ($msg->header->type0 == 'message' && $msg->header->type1 == 'rfc822' && $elem_num == 8) {
 224               // This is an encapsulated message, so lets start all over again and
 225               // parse this message adding it on to the existing one.
 226               $structure = trim($structure);
 227               if ( $structure{0} == '(' ) {
 228                  $e = mime_match_parenthesis (0, $structure);
 229                  $structure = substr($structure, 0, $e);
 230                  $structure = substr($structure, 1);
 231                  $m = mime_parse_structure($structure, $msg->header->entity_id);
 232
 233                  // the following conditional is there to correct a bug that wasn't
 234                  // incrementing the entity IDs correctly because of the special case
 235                  // that message/rfc822 is.  This fixes it fine.
 236                  if (substr($structure, 1, 1) != '(')
 237                     $m->header->entity_id = mime_increment_id(mime_new_element_level($ent_id));
 238
 239                  // Now we'll go through and reformat the results.
 240                  if ($m->entities) {
 241                     for ($i=0; $i < count($m->entities); $i++) {
 242                        $msg->addEntity($m->entities[$i]);
 243                     }
 244                  } else {
 245                     $msg->addEntity($m);
 246                  }
 247                  $structure = "";
 248               }
 249            }
 250            break;
 251      }
 252      $elem_num++;
 253      $text = "";
 254   }
 255   // loop through the additional properties and put those in the various headers
 256   if ($msg->header->type0 != 'message') {
 257      for ($i=0; $i < count($properties); $i++) {
 258         $msg->header->{$properties[$i]['name']} = $properties[$i]['value'];
 259      }
 260   }
 261
 262   return $msg;
 263 }
 264
 265 /*
 266  * I did most of the MIME stuff yesterday (June 20, 2000), but I couldn't
 267  * figure out how to do this part, so I decided to go to bed.  I woke up
 268  * in the morning and had a flash of insight.  I went to the white-board
 269  * and scribbled it out, then spent a bit programming it, and this is the
 270  * result.  Nothing complicated, but I think my brain was fried yesterday.
 271  * Funny how that happens some times.
 272  *
 273  * This gets properties in a nested parenthesisized list.  For example,
 274  * this would get passed something like:  ("attachment" ("filename" "luke.tar.gz"))
 275  * This returns an array called $props with all paired up properties.
 276  * It ignores the "attachment" for now, maybe that should change later
 277  * down the road.  In this case, what is returned is:
 278  *    $props[0]["name"] = "filename";
 279  *    $props[0]["value"] = "luke.tar.gz";
 280  */
 281 function mime_get_props ($props, $structure) {
 282
 283   while (strlen($structure) > 0) {
 284      $structure = trim($structure);
 285      $char = $structure{0};
 286
 287      if ($char == '"') {
 288         $pos = 1;
 289         $tmp = '';
 290         while ( ( $char = $structure{$pos} ) != '"' &&
 291                 $pos < strlen($structure)) {
 292            $tmp .= $char;
 293            $pos++;
 294         }
 295         $structure = trim(substr($structure, strlen($tmp) + 2));
 296         $char = $structure{0};
 297
 298         if ($char == '"') {
 299            $pos = 1;
 300            $value = '';
 301            while ( ( $char = $structure{$pos} ) != '"' &&
 302                    $pos < strlen($structure) ) {
 303               $value .= $char;
 304               $pos++;
 305            }
 306            $structure = trim(substr($structure, strlen($tmp) + 2));
 307
 308            $k = count($props);
 309            $props[$k]['name'] = strtolower($tmp);
 310            $props[$k]['value'] = $value;
 311         } else if ($char == '(') {
 312            $end = mime_match_parenthesis (0, $structure);
 313            $sub = substr($structure, 1, $end-1);
 314        if (! isset($props))
 315            $props = array();
 316            $props = mime_get_props($props, $sub);
 317            $structure = substr($structure, strlen($sub) + 2);
 318         }
 319         return $props;
 320      } else if ($char == '(') {
 321         $end = mime_match_parenthesis (0, $structure);
 322         $sub = substr($structure, 1, $end-1);
 323         $props = mime_get_props($props, $sub);
 324         $structure = substr($structure, strlen($sub) + 2);
 325         return $props;
 326      } else {
 327         return $props;
 328      }
 329   }
 330 }
 331
 332 /*
 333  *  Matches parenthesis.  It will return the position of the matching
 334  *  parenthesis in $structure.  For instance, if $structure was:
 335  *     ("text" "plain" ("val1name", "1") nil ... )
 336  *     x                                         x
 337  *  then this would return 42 to match up those two.
 338  */
 339 function mime_match_parenthesis ($pos, $structure) {
 340
 341     $j = strlen( $structure );
 342
 343     // ignore all extra characters
 344     // If inside of a string, skip string -- Boundary IDs and other
 345     // things can have ) in them.
 346     if ( $structure{$pos} != '(' ) {
 347         return( $j );
 348     }
 349
 350     while ( $pos < $j ) {
 351         $pos++;
 352         if ($structure{$pos} == ')') {
 353             return $pos;
 354         } elseif ($structure{$pos} == '"') {
 355             $pos++;
 356             while ( $structure{$pos} != '"' &&
 357                     $pos < $j ) {
 358                if (substr($structure, $pos, 2) == '\\"') {
 359                   $pos++;
 360                } elseif (substr($structure, $pos, 2) == '\\\\') {
 361                   $pos++;
 362                }
 363                $pos++;
 364             }
 365         } elseif ( $structure{$pos} == '(' ) {
 366             $pos = mime_match_parenthesis ($pos, $structure);
 367         }
 368     }
 369     echo _("Error decoding mime structure.  Report this as a bug!") . '<br>';
 370     return( $pos );
 371 }
 372
 373 function mime_fetch_body ($imap_stream, $id, $ent_id ) {
 374     // do a bit of error correction.  If we couldn't find the entity id, just guess
 375     // that it is the first one.  That is usually the case anyway.
 376     if (!$ent_id)
 377         $ent_id = 1;
 378     $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id]", true, $response, $message);
 379     $topline = array_shift($data);
 380     while (! ereg('\\* [0-9]+ FETCH ', $topline) && $data)
 381         $topline = array_shift($data);
 382     $wholemessage = implode('', $data);
 383     if (ereg('\\{([^\\}]*)\\}', $topline, $regs)) {
 384         $ret = substr( $wholemessage, 0, $regs[1] );
 385         /*
 386             There is some information in the content info header that could be important
 387             in order to parse html messages. Let's get them here.
 388         */
 389         if ( $ret{0} == '<' ) {
 390             $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id.MIME]", true, $response, $message);
 391             $base = '';
 392             $k = 10;
 393             foreach( $data as $d ) {
 394                 if ( substr( $d, 0, 13 ) == 'Content-Base:' ) {
 395                     $j = strlen( $d );
 396                     $i = 13;
 397                     $base = '';
 398                     while ( $i < $j &&
 399                            ( !isNoSep( $d{$i} ) || $d{$i} == '"' )  )
 400                         $i++;
 401                     while ( $i < $j ) {
 402                         if ( isNoSep( $d{$i} ) )
 403                             $base .= $d{$i};
 404                         $i++;
 405                     }
 406                     $k = 0;
 407                 } elseif ( $k == 1 && !isnosep( $d{0} ) ) {
 408                     $base .= substr( $d, 1 );
 409                 }
 410                 $k++;
 411             }
 412             if ( $base <> '' )
 413
 414                 $ret = "<base href=\"$base\">" . $ret;
 415         }
 416     } else if (ereg('"([^"]*)"', $topline, $regs)) {
 417         $ret = $regs[1];
 418     } else {
 419         global $where, $what, $mailbox, $passed_id, $startMessage;
 420         $par = "mailbox=".urlencode($mailbox)."&passed_id=$passed_id";
 421         if (isset($where) && isset($what)) {
 422             $par .= "&where=".urlencode($where)."&what=".urlencode($what);
 423         } else {
 424             $par .= "&startMessage=$startMessage&show_more=0";
 425         }
 426         $par .= '&response='.urlencode($response).'&message='.urlencode($message).
 427                 '&topline='.urlencode($topline);
 428
 429         echo   '<b><font color=$color[2]>' .
 430                _("Body retrieval error. The reason for this is most probably that the message is malformed. Please help us making future versions better by submitting this message to the developers knowledgebase!") .
 431                "<A HREF=\"../src/retrievalerror.php?$par\">Submit message</A><BR>" .
 432                '<tt>' . _("Response:") . "$response<BR>" .
 433                _("Message:") . " $message<BR>" .
 434                _("FETCH line:") . " $topline<BR></tt></font></b>";
 435
 436         $data = sqimap_run_command ($imap_stream, "FETCH $passed_id BODY[]", true, $response, $message);
 437         array_shift($data);
 438         $wholemessage = implode('', $data);
 439
 440         $ret = "---------------\n$wholemessage";
 441
 442     }
 443     return( $ret );
 444 }
 445
 446 function mime_print_body_lines ($imap_stream, $id, $ent_id, $encoding) {
 447     // do a bit of error correction.  If we couldn't find the entity id, just guess
 448     // that it is the first one.  That is usually the case anyway.
 449     if (!$ent_id) {
 450         $ent_id = 1;
 451     }
 452     $sid = sqimap_session_id();
 453     // Don't kill the connection if the browser is over a dialup
 454     // and it would take over 30 seconds to download it.
 455
 456     // don´t call set_time_limit in safe mode.
 457     if (!ini_get("safe_mode")) {
 458         set_time_limit(0);
 459     }
 460
 461     fputs ($imap_stream, "$sid FETCH $id BODY[$ent_id]\r\n");
 462     $cnt = 0;
 463     $continue = true;
 464     $read = fgets ($imap_stream,4096);
 465     // This could be bad -- if the section has sqimap_session_id() . ' OK'
 466     // or similar, it will kill the download.
 467     while (!ereg("^".$sid." (OK|BAD|NO)(.*)$", $read, $regs)) {
 468       if (trim($read) == ')==') {
 469           $read1 = $read;
 470           $read = fgets ($imap_stream,4096);
 471           if (ereg("^".$sid." (OK|BAD|NO)(.*)$", $read, $regs)) {
 472               return;
 473           } else {
 474               echo decodeBody($read1, $encoding) .
 475                    decodeBody($read, $encoding);
 476           }
 477       } else if ($cnt) {
 478           echo decodeBody($read, $encoding);
 479       }
 480       $read = fgets ($imap_stream,4096);
 481       $cnt++;
 482     }
 483 }
 484
 485 /* -[ END MIME DECODING ]----------------------------------------------------------- */
 486
 487
 488
 489 /* This is the first function called.  It decides if this is a multipart
 490    message or if it should be handled as a single entity
 491  */
 492 function decodeMime ($imap_stream, &$header) {
 493     global $username, $key, $imapServerAddress, $imapPort;
 494     return mime_structure ($imap_stream, $header);
 495 }
 496
 497 // This is here for debugging purposese.  It will print out a list
 498 // of all the entity IDs that are in the $message object.
 499 /*
 500 function listEntities ($message) {
 501 if ($message) {
 502  if ($message->header->entity_id)
 503  echo "<tt>" . $message->header->entity_id . ' : ' . $message->header->type0 . '/' . $message->header->type1 . '<br>';
 504  for ($i = 0; $message->entities[$i]; $i++) {
 505     $msg = listEntities($message->entities[$i], $ent_id);
 506     if ($msg)
 507        return $msg;
 508  }
 509 }
 510 }
 511 */
 512
 513 /* returns a $message object for a particular entity id */
 514 function getEntity ($message, $ent_id) {
 515     if ($message) {
 516         if ($message->header->entity_id == $ent_id && strlen($ent_id) == strlen($message->header->entity_id)) {
 517             return $message;
 518         } else {
 519             for ($i = 0; isset($message->entities[$i]); $i++) {
 520                 $msg = getEntity ($message->entities[$i], $ent_id);
 521                 if ($msg) {
 522                     return $msg;
 523                 }
 524             }
 525         }
 526     }
 527 }
 528
 529 /*
 530  * figures out what entity to display and returns the $message object
 531  * for that entity.
 532  */
 533 function findDisplayEntity ($message, $textOnly = 1)   {
 534     global $show_html_default;
 535
 536     $entity = 0;
 537
 538     if ($message) {
 539         if ( $message->header->type0 == 'multipart' &&
 540              ( $message->header->type1 == 'alternative' ||
 541                $message->header->type1 == 'related' ) &&
 542              $show_html_default && ! $textOnly ) {
 543             $entity = findDisplayEntityHTML($message);
 544         }
 545
 546         // Show text/plain or text/html -- the first one we find.
 547         if ( $entity == 0 &&
 548              $message->header->type0 == 'text' &&
 549              ( $message->header->type1 == 'plain' ||
 550                $message->header->type1 == 'html' ) &&
 551              isset($message->header->entity_id) ) {
 552             $entity = $message->header->entity_id;
 553         }
 554
 555         $i = 0;
 556         while ($entity == 0 && isset($message->entities[$i]) ) {
 557             $entity = findDisplayEntity($message->entities[$i], $textOnly);
 558             $i++;
 559         }
 560     }
 561
 562     return( $entity );
 563 }
 564
 565 /* Shows the HTML version */
 566 function findDisplayEntityHTML ($message) {
 567
 568     if ( $message->header->type0 == 'text' &&
 569          $message->header->type1 == 'html' &&
 570          isset($message->header->entity_id)) {
 571         return $message->header->entity_id;
 572     }
 573     for ($i = 0; isset($message->entities[$i]); $i ++) {
 574         $entity = findDisplayEntityHTML($message->entities[$i]);
 575         if ($entity != 0) {
 576             return $entity;
 577         }
 578     }
 579
 580     return 0;
 581 }
 582
 583 /* This returns a parsed string called $body. That string can then
 584 be displayed as the actual message in the HTML. It contains
 585 everything needed, including HTML Tags, Attachments at the
 586 bottom, etc.
 587 */
 588 function formatBody($imap_stream, $message, $color, $wrap_at) {
 589     // this if statement checks for the entity to show as the
 590     // primary message. To add more of them, just put them in the
 591     // order that is their priority.
 592     global $startMessage, $username, $key, $imapServerAddress, $imapPort,
 593            $show_html_default;
 594
 595     $id = $message->header->id;
 596     $urlmailbox = urlencode($message->header->mailbox);
 597
 598     // Get the right entity and redefine message to be this entity
 599     // Pass the 0 to mean that we want the 'best' viewable one
 600     $ent_num = findDisplayEntity ($message, 0);
 601     $body_message = getEntity($message, $ent_num);
 602     if (($body_message->header->type0 == 'text') ||
 603         ($body_message->header->type0 == 'rfc822')) {
 604
 605         $body = mime_fetch_body ($imap_stream, $id, $ent_num);
 606         $body = decodeBody($body, $body_message->header->encoding);
 607         $hookResults = do_hook("message_body", $body);
 608         $body = $hookResults[1];
 609
 610         // If there are other types that shouldn't be formatted, add
 611         // them here
 612         if ($body_message->header->type1 == 'html') {
 613             if ( $show_html_default <> 1 ) {
 614                 $body = strip_tags( $body );
 615                 translateText($body, $wrap_at, $body_message->header->charset);
 616             } else {
 617                 $body = MagicHTML( $body, $id );
 618             }
 619         } else {
 620             translateText($body, $wrap_at, $body_message->header->charset);
 621         }
 622
 623         $body .= "<SMALL><CENTER><A HREF=\"../src/download.php?absolute_dl=true&passed_id=$id&passed_ent_id=$ent_num&mailbox=$urlmailbox&showHeaders=1\">". _("Download this as a file") ."</A></CENTER><BR></SMALL>";
 624
 625         /** Display the ATTACHMENTS: message if there's more than one part **/
 626         $body .= "</TD></TR></TABLE>";
 627         if (isset($message->entities[0])) {
 628             $body .= formatAttachments ($message, $ent_num, $message->header->mailbox, $id);
 629         }
 630         $body .= "</TD></TR></TABLE>";
 631     } else {
 632         $body = formatAttachments ($message, -1, $message->header->mailbox, $id);
 633     }
 634     return ($body);
 635 }
 636
 637 /*
 638  * A recursive function that returns a list of attachments with links
 639  * to where to download these attachments
 640  */
 641 function formatAttachments ($message, $ent_id, $mailbox, $id) {
 642   global $where, $what;
 643   global $startMessage, $color;
 644   static $ShownHTML = 0;
 645
 646   $body = "";
 647   if ($ShownHTML == 0) {
 648         $ShownHTML = 1;
 649
 650         $body .= "<TABLE WIDTH=\"100%\" CELLSPACING=0 CELLPADDING=2 BORDER=0 BGCOLOR=\"$color[0]\"><TR>\n" .
 651                  "<TH ALIGN=\"left\" BGCOLOR=\"$color[9]\"><B>\n" .
 652                  _("Attachments") . ':' .
 653                  "</B></TH></TR><TR><TD>\n" .
 654                  "<TABLE CELLSPACING=0 CELLPADDING=1 BORDER=0>\n" .
 655                  formatAttachments ($message, $ent_id, $mailbox, $id) .
 656                  "</TABLE></TD></TR></TABLE>";
 657
 658         return( $body );
 659   }
 660
 661   if ($message) {
 662      if (!$message->entities) {
 663         $type0 = strtolower($message->header->type0);
 664         $type1 = strtolower($message->header->type1);
 665         $name = decodeHeader($message->header->name);
 666
 667         if ($message->header->entity_id != $ent_id) {
 668            $filename = decodeHeader($message->header->filename);
 669            if (trim($filename) == '') {
 670               if (trim($name) == '') {
 671                  if ( trim( $message->header->id ) == '' )
 672                     $display_filename = 'untitled-[' . $message->header->entity_id . ']' ;
 673                  else
 674                     $display_filename = 'cid: ' . $message->header->id;
 675                  // $display_filename = 'untitled-[' . $message->header->entity_id . ']' ;
 676               } else {
 677                  $display_filename = $name;
 678                  $filename = $name;
 679               }
 680            } else {
 681               $display_filename = $filename;
 682            }
 683
 684            $urlMailbox = urlencode($mailbox);
 685            $ent = urlencode($message->header->entity_id);
 686
 687            $DefaultLink =
 688               "../src/download.php?startMessage=$startMessage&passed_id=$id&mailbox=$urlMailbox&passed_ent_id=$ent";
 689            if ($where && $what)
 690               $DefaultLink .= '&where=' . urlencode($where) . '&what=' . urlencode($what);
 691            $Links['download link']['text'] = _("download");
 692            $Links['download link']['href'] =
 693                "../src/download.php?absolute_dl=true&passed_id=$id&mailbox=$urlMailbox&passed_ent_id=$ent";
 694            $ImageURL = '';
 695
 696            /* this executes the attachment hook with a specific MIME-type.
 697             * if that doens't have results, it tries if there's a rule
 698             * for a more generic type. */
 699            $HookResults = do_hook("attachment $type0/$type1", $Links,
 700                $startMessage, $id, $urlMailbox, $ent, $DefaultLink,
 701                $display_filename, $where, $what);
 702            if(count($HookResults[1]) <= 1) {
 703                $HookResults = do_hook("attachment $type0/*", $Links,
 704                $startMessage, $id, $urlMailbox, $ent, $DefaultLink,
 705                $display_filename, $where, $what);
 706            }
 707
 708            $Links = $HookResults[1];
 709            $DefaultLink = $HookResults[6];
 710
 711            $body .= '<TR><TD>&nbsp;&nbsp;</TD><TD>' .
 712                     "<A HREF=\"$DefaultLink\">$display_filename</A>&nbsp;</TD>" .
 713                     '<TD><SMALL><b>' . show_readable_size($message->header->size) .
 714                     '</b>&nbsp;&nbsp;</small></TD>' .
 715                     "<TD><SMALL>[ $type0/$type1 ]&nbsp;</SMALL></TD>" .
 716                     '<TD><SMALL>';
 717            if ($message->header->description)
 718               $body .= '<b>' . htmlspecialchars($message->header->description) . '</b>';
 719            $body .= '</SMALL></TD><TD><SMALL>&nbsp;';
 720
 721
 722            $SkipSpaces = 1;
 723            foreach ($Links as $Val) {
 724               if ($SkipSpaces) {
 725                  $SkipSpaces = 0;
 726               } else {
 727                  $body .= '&nbsp;&nbsp;|&nbsp;&nbsp;';
 728               }
 729               $body .= '<a href="' . $Val['href'] . '">' .  $Val['text'] . '</a>';
 730            }
 731
 732            unset($Links);
 733
 734            $body .= "</SMALL></TD></TR>\n";
 735         }
 736      } else {
 737         for ($i = 0; $i < count($message->entities); $i++) {
 738            $body .= formatAttachments ($message->entities[$i], $ent_id, $mailbox, $id);
 739         }
 740      }
 741      return( $body );
 742   }
 743 }
 744
 745
 746 /** this function decodes the body depending on the encoding type. **/
 747 function decodeBody($body, $encoding) {
 748   $body = str_replace("\r\n", "\n", $body);
 749   $encoding = strtolower($encoding);
 750
 751   global $show_html_default;
 752
 753   if ($encoding == 'quoted-printable') {
 754      $body = quoted_printable_decode($body);
 755
 756
 757      while (ereg("=\n", $body))
 758         $body = ereg_replace ("=\n", "", $body);
 759
 760   } else if ($encoding == 'base64') {
 761      $body = base64_decode($body);
 762   }
 763
 764   // All other encodings are returned raw.
 765   return $body;
 766 }
 767
 768 /*
 769  * This functions decode strings that is encoded according to
 770  * RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
 771  */
 772 function decodeHeader ($string, $utfencode=true) {
 773
 774 if ( is_array( $string ) ) {
 775     $string = implode("\n", $string );
 776 }
 777
 778 if (eregi('=\\?([^?]+)\\?(q|b)\\?([^?]+)\\?=',
 779             $string, $res)) {
 780     if (ucfirst($res[2]) == 'B') {
 781         $replace = base64_decode($res[3]);
 782     } else {
 783         $replace = str_replace('_', ' ', $res[3]);
 784         // Convert lowercase Quoted Printable to uppercase for
 785         // quoted_printable_decode to understand it.
 786         while (ereg("(=(([0-9][abcdef])|([abcdef][0-9])|([abcdef][abcdef])))",
 787                $replace, $res)) {
 788             $replace = str_replace($res[1], strtoupper($res[1]), $replace);
 789         }
 790         $replace = quoted_printable_decode($replace);
 791     }
 792     /* Only encode into entities by default. Some places
 793         don't need the encoding, like the compose form. */
 794     if ($utfencode){
 795         $replace = charset_decode ($res[1], $replace);
 796     }
 797
 798     // Remove the name of the character set.
 799     $string = eregi_replace ('=\\?([^?]+)\\?(q|b)\\?([^?]+)\\?=',
 800               $replace, $string);
 801
 802     // In case there should be more encoding in the string: recurse
 803     $string = decodeHeader($string);
 804 }
 805
 806 return ($string);
 807 }
 808
 809 /*
 810  * Encode a string according to RFC 1522 for use in headers if it
 811  * contains 8-bit characters or anything that looks like it should
 812  * be encoded.
 813  */
 814 function encodeHeader ($string) {
 815     global $default_charset;
 816
 817     // Encode only if the string contains 8-bit characters or =?
 818     $j = strlen( $string  );
 819     $l = strstr($string, '=?');         // Must be encoded ?
 820     $ret = '';
 821     for( $i=0; $i < $j; ++$i) {
 822         switch( $string{$i} ) {
 823            case '=':
 824           $ret .= '=3D';
 825           break;
 826         case '?':
 827           $ret .= '=3F';
 828           break;
 829         case '_':
 830           $ret .= '=5F';
 831           break;
 832         case ' ':
 833           $ret .= '_';
 834           break;
 835         default:
 836           $k = ord( $string{$i} );
 837           if ( $k > 126 ) {
 838              $ret .= sprintf("=%02X", $k);
 839              $l = TRUE;
 840           } else
 841              $ret .= $string{$i};
 842         }
 843     }
 844
 845     if ( $l ) {
 846         $string = "=?$default_charset?Q?$ret?=";
 847     }
 848
 849     return( $string );
 850 }
 851
 852 /*
 853     Strips dangerous tags from html messages.
 854 */
 855 function MagicHTML( $body, $id ) {
 856
 857     global $message, $HTTP_SERVER_VARS,
 858            $attachment_common_show_images;
 859
 860     $attachment_common_show_images =
 861                      FALSE; // Don't display attached images in HTML mode
 862     $j = strlen( $body );   // Legnth of the HTML
 863     $ret = '';              // Returned string
 864     $bgcolor = '#ffffff';   // Background style color (defaults to white)
 865     $textcolor = '#000000'; // Foreground style color (defaults to black)
 866     $leftmargin = '';       // Left margin style
 867     $title = '';            // HTML title if any
 868
 869     $i = 0;
 870     while ( $i < $j ) {
 871         if ( $body{$i} == '<' ) {
 872             $pos = $i + 1;
 873             $tag = '';
 874             while ($body{$pos} == ' ' || $body{$pos} == "\t" ||
 875                    $body{$pos} == "\n") {
 876                 $pos ++;
 877             }
 878             while (strlen($tag) < 4 && $body{$pos} != ' ' &&
 879                    $body{$pos} != "\t" && $body{$pos} != "\n") {
 880                 $tag .= $body{$pos};
 881                 $pos ++;
 882             }
 883             switch( strtoupper( $tag ) ) {
 884             // Strips the entire tag and contents
 885             case 'APPL':
 886             case 'EMBB':
 887             case 'FRAM':
 888             case 'SCRI':
 889             case 'OBJE':
 890                 $etg = '/' . $tag;
 891                 while ( $body{$i+1}.$body{$i+2}.$body{$i+3}.$body{$i+4}.$body{$i+5} <> $etg  &&
 892                        $i < $j  ) $i++;
 893                 while ( $i < $j && $body{++$i} <> '>' );
 894                 // $ret .= "<!-- $tag removed -->";
 895                 break;
 896             // Substitute Title
 897             case 'TITL':
 898                 $i += 5;
 899                 while ( $body{$i} <> '>' &&  // </title>
 900                        $i < $j )
 901                         $i++;
 902                 $i++;
 903                 $title = '';
 904                 while ( $body{$i} <> '<' &&  // </title>
 905                        $i < $j ) {
 906                     $title .= $body{$i};
 907                     $i++;
 908                 }
 909                 $i += 7;
 910                 break;
 911             // Destroy these tags
 912             case 'HTML':
 913             case 'HEAD':
 914             case '/HTM':
 915             case '/HEA':
 916             case '!DOC':
 917             case 'META':
 918             //case 'DIV ':
 919             //case '/DIV':
 920             case '!-- ':
 921                 $i += 4;
 922                 while ( $body{$i}  <> '>' &&
 923                        $i < $j )
 924                     $i++;
 925                 // $i++;
 926                 break;
 927             case 'STYL':
 928                 $i += 5;
 929                 while ( $body{$i} <> '>' &&  // </title>
 930                        $i < $j )
 931                         $i++;
 932                 $i++;
 933                 // We parse the style to look for interesting stuff
 934                 $styleblk = '';
 935                 while ( $body{$i} <> '>' &&
 936                        $i < $j ) {
 937                     // First we get the name of the style
 938                     $style = '';
 939                     while ( $body{$i} <> '>' &&
 940                            $body{$i} <> '<' &&
 941                            $body{$i} <> '{' &&
 942                            $i < $j ) {
 943                        if ( isnoSep( $body{$i} ) )
 944                            $style .= $body{$i};
 945                        $i++;
 946                     }
 947                     stripComments( $i, $j, $body );
 948                     $style = strtoupper( trim( $style ) );
 949                     if ( $style == 'BODY' ) {
 950                         // Next we look into the definitions of the body style
 951                         while ( $body{$i} <> '>' &&
 952                                $body{$i} <> '}' &&
 953                                $i < $j ) {
 954                             // We look for the background color if any.
 955                             if ( substr( $body, $i, 17 ) == 'BACKGROUND-COLOR:' ) {
 956                                 $i += 17;
 957                                 $bgcolor = getStyleData( $i, $j, $body );
 958                             } elseif ( substr( $body, $i, 12 ) == 'MARGIN-LEFT:' ) {
 959                                 $i += 12;
 960                                 $leftmargin = getStyleData( $i, $j, $body );
 961                             }
 962                             $i++;
 963                         }
 964                     } else {
 965                         // Other style are mantained
 966                         $styleblk .= "$style ";
 967                         while ( $body{$i} <> '>' &&
 968                                $body{$i} <> '<' &&
 969                                $body{$i} <> '}' &&
 970                                $i < $j ) {
 971                             $styleblk .= $body{$i};
 972                             $i++;
 973                         }
 974                         $styleblk .= $body{$i};
 975                     }
 976                     stripComments( $i, $j, $body );
 977                     if ( $body{$i} <> '>' )
 978                         $i++;
 979                 }
 980                 if ( $styleblk <> '' )
 981                     $ret .= "<style>$styleblk";
 982                 break;
 983             case 'BODY':
 984                 if ( $title <> '' )
 985                     $ret .= '<b>' . _("Title:") . " </b>$title<br>\n";
 986                 $ret .= "<TABLE";
 987                 $i += 5;
 988                 if (! isset($base)) {
 989                     $base = '';
 990                 }
 991                 $ret .= stripEvent( $i, $j, $body, $id, $base );
 992                 $ret .= " bgcolor=$bgcolor width=\"100%\"><tr>";
 993                 if ( $leftmargin <> '' )
 994                     $ret .= "<td width=$leftmargin>&nbsp;</td>";
 995                 $ret .= '<td>';
 996                 if (strtolower($bgcolor) == 'ffffff' ||
 997                     strtolower($bgcolor) == '#ffffff')
 998                     $ret .= '<font color=#000000>';
 999                 break;
1000             case 'BASE':
1001                 $i += 5;
1002                 $base = '';
1003                 while ( !isNoSep( $body{$i} ) &&
1004                        $i < $j ) {
1005                         $i++;
1006                 }
1007                 if ( strcasecmp( substr( $base, 0, 4 ), 'href'  ) ) {
1008                         $i += 5;
1009                         while ( !isNoSep( $body{$i} ) &&
1010                                $i < $j ) {
1011                                 $i++;
1012                         }
1013                         while ( $body{$i} <> '>' &&
1014                                $i < $j ) {
1015                             if ( $body{$i} <> '"' ) {
1016                                 $base .= $body{$i};
1017                             }
1018                             $i++;
1019                         }
1020                         // Debuging $ret .= "<!-- base == $base -->";
1021                         if ( strcasecmp( substr( $base, 0, 4 ), 'file' ) <> 0 ) {
1022                             $ret .= "\n<BASE HREF=\"$base\">\n";
1023                         }
1024                 }
1025                 break;
1026             case '/BOD':
1027                 $ret .= '</font></td></tr></TABLE>';
1028                 $i += 6;
1029                 break;
1030             default:
1031                 // Following tags can contain some event handler, lets search it
1032                 stripComments( $i, $j, $body );
1033                 if (! isset($base)) {
1034                    $base = '';
1035                 }
1036                 $ret .= stripEvent( $i, $j, $body, $id, $base ) . '>';
1037                         // $ret .= "<!-- $tag detected -->";
1038             }
1039         } else {
1040             $ret .= $body{$i};
1041         }
1042     $i++;
1043     }
1044
1045 return( "\n\n<!-- HTML Output ahead -->\n" .
1046         $ret .
1047         "\n<!-- END of HTML Output --><base href=\"".
1048         get_location() . '/'.
1049         "\">\n\n" );
1050 }
1051
1052 function isNoSep( $char ) {
1053
1054     switch( $char ) {
1055     case ' ':
1056     case "\n":
1057     case "\t":
1058     case "\r":
1059     case '>':
1060     case '"':
1061         return( FALSE );
1062         break;
1063     default:
1064         return( TRUE );
1065     }
1066
1067 }
1068
1069 /*
1070   The following function is usefull to remove extra data that can cause
1071   html not to display properly. Especialy with MS stuff.
1072 */
1073
1074 function stripComments( &$i, $j, &$body ) {
1075
1076     while ( $body{$i}.$body{$i+1}.$body{$i+2}.$body{$i+3} == '<!--' &&
1077            $i < $j ) {
1078         $i += 5;
1079         while ( $body{$i-2}.$body{$i-1}.$body{$i} <> '-->' &&
1080                $i < $j )
1081             $i++;
1082         $i++;
1083     }
1084
1085     return;
1086
1087 }
1088
1089 /* Gets the style data of a specific style */
1090
1091 function getStyleData( &$i, $j, &$body ) {
1092
1093     // We skip spaces
1094     while ( $body{$i} <> '>' && !isNoSep( $body{$i} ) &&
1095            $i < $j ) {
1096         $i++;
1097     }
1098     // And get the color
1099     $ret = '';
1100     while ( isNoSep( $body{$i} ) &&
1101            $i < $j ) {
1102         $ret .= $body{$i};
1103         $i++;
1104     }
1105
1106     return( $ret );
1107 }
1108
1109 /*
1110 Private function for strip_dangerous_tag. Look for event based coded and "remove" it
1111 change on with no (onload -> noload)
1112 */
1113
1114 function stripEvent( &$i, $j, &$body, $id, $base ) {
1115
1116     global $message, $base_uri;
1117
1118     $ret = '';
1119
1120     while ( $body{$i} <> '>' &&
1121            $i < $j ) {
1122         $etg = strtolower($body{$i}.$body{$i+1}.$body{$i+2});
1123         switch( $etg ) {
1124         case 'src':
1125             // This is probably a src specification
1126             $k = $i + 3;
1127             while( !isNoSep( $body{$k} )) {
1128                 $k++;
1129             }
1130             if ( $body{$k} == '=' ) {
1131                 /* It is indeed */
1132                 $k++;
1133                 while( !isNoSep( $body{$k} ) &&
1134                        $k < $j ) {
1135                     $k++;
1136                 }
1137                 $src = '';
1138                 while ( $body{$k} <> '>' && isNoSep( $body{$k} ) &&
1139                        $k < $j ) {
1140                     $src .= $body{$k};
1141                     $k++;
1142                 }
1143                 while( !isNoSep( $body{$k} ) &&
1144                        $k < $j ) {
1145                     $k++;
1146                 }
1147                 if ( strtolower( substr( $src, 0, 4 ) ) == 'cid:' ) {
1148                     $src = substr( $src, 4 );
1149                     $src = "../src/download.php?absolute_dl=true&passed_id=$id&mailbox=" .
1150                            urlencode( $message->header->mailbox ) .
1151                            "&passed_ent_id=" . find_ent_id( $src, $message );
1152                 } else if ( strtolower( substr( $src, 0, 4 ) ) <> 'http' ||
1153                             stristr( $src, $base_uri ) ) {
1154                     /* Javascript and local urls goes out */
1155                     $src = '../images/' . _("sec_remove_eng.png");
1156                 }
1157                 $ret .= 'src="' . $src . '" ';
1158                 $i = $k - 2;
1159             } else {
1160                 $ret .= 'src';
1161                 $i = $i + 3;
1162             }
1163
1164             break;
1165         case '../':
1166             // Retrolinks are not allowed without a base because they mess with SM security
1167             if ( $base == '' ) {
1168                     $i += 2;
1169             } else {
1170                     $ret .= '.';
1171             }
1172             break;
1173         case 'cid':
1174             // Internal link
1175             $k = $i-1;
1176             if ( $body{$i+3} == ':') {
1177                 $i +=4;
1178                 $name = '';
1179                 while ( isNoSep( $body{$i} ) &&
1180                        $i < $j  ) {
1181                     $name .= $body{$i++};
1182                 }
1183                 if ( $name <> '' ) {
1184                     $ret .= "../src/download.php?absolute_dl=true&passed_id=$id&mailbox=" .
1185                                 urlencode( $message->header->mailbox ) .
1186                                 "&passed_ent_id=" . find_ent_id( $name, $message );
1187                     if ( $body{$k} == '"' )
1188                         $ret .= '" ';
1189                     else
1190                         $ret .= ' ';
1191                 }
1192                 if ( $body{$i} == '>' )
1193                     $i -= 1;
1194             }
1195             break;
1196         case ' on':
1197         case "\non":
1198         case "\ron":
1199         case "\ton":
1200             $ret .= ' no';
1201             $i += 2;
1202             break;
1203         case 'pt:':
1204             if ( strcasecmp( $body{$i-4}.$body{$i-3}.$body{$i-2}.$body{$i-1}.$body{$i}.$body{$i+1}.$body{$i+2}, 'script:') == 0 ) {
1205                 $ret .= '_no/';
1206             } else {
1207                 $ret .= $etg;
1208             }
1209             $i += 2;
1210             break;
1211         default:
1212             $ret .= $body{$i};
1213         }
1214         $i++;
1215     }
1216     return( $ret );
1217 }
1218
1219
1220 /* This function trys to locate the entity_id of a specific mime element */
1221
1222 function find_ent_id( $id, $message ) {
1223
1224     $ret = '';
1225     for ($i=0; $ret == '' && $i < count($message->entities); $i++) {
1226
1227         if ( $message->entities[$i]->header->entity_id == '' ) {
1228             $ret = find_ent_id( $id, $message->entities[$i] );
1229         } else {
1230             if ( strcasecmp( $message->entities[$i]->header->id, $id ) == 0 )
1231                 $ret = $message->entities[$i]->header->entity_id;
1232         }
1233
1234     }
1235
1236     return( $ret );
1237
1238 }
1239 ?>