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 = '', $entities = array();
  37
  38     function addEntity ($msg) {
  39         $this->entities[] = $msg;
  40     }
  41 }
  42
  43 /* --------------------------------------------------------------------------------- */
  44 /* MIME DECODING                                                                     */
  45 /* --------------------------------------------------------------------------------- */
  46
  47 /* This function gets the structure of a message and stores it in the "message" class.
  48  * It will return this object for use with all relevant header information and
  49  * fully parsed into the standard "message" object format.
  50  */
  51 function mime_structure ($imap_stream, $header) {
  52
  53     sqimap_messages_flag ($imap_stream, $header->id, $header->id, 'Seen');
  54     $ssid = sqimap_session_id();
  55     $lsid = strlen( $ssid );
  56     $id = $header->id;
  57     fputs ($imap_stream, "$ssid FETCH $id BODYSTRUCTURE\r\n");
  58     //
  59     // This should use sqimap_read_data instead of reading it itself
  60     //
  61     $read = fgets ($imap_stream, 9216);
  62     $bodystructure = '';
  63     while ( substr($read, 0, $lsid) <> $ssid &&
  64          !feof( $imap_stream ) ) {
  65         $bodystructure .= $read;
  66         $read = fgets ($imap_stream, 9216);
  67     }
  68     $read = $bodystructure;
  69
  70     // isolate the body structure and remove beginning and end parenthesis
  71     $read = trim(substr ($read, strpos(strtolower($read), 'bodystructure') + 13));
  72     $read = trim(substr ($read, 0, -1));
  73     $end = mime_match_parenthesis(0, $read);
  74     while ($end == strlen($read)-1) {
  75         $read = trim(substr ($read, 0, -1));
  76         $read = trim(substr ($read, 1));
  77         $end = mime_match_parenthesis(0, $read);
  78     }
  79
  80     $msg = mime_parse_structure ($read, 0);
  81     $msg->header = $header;
  82
  83     return( $msg );
  84 }
  85
  86 /* this starts the parsing of a particular structure.  It is called recursively,
  87  * so it can be passed different structures.  It returns an object of type
  88  * $message.
  89  * First, it checks to see if it is a multipart message.  If it is, then it
  90  * handles that as it sees is necessary.  If it is just a regular entity,
  91  * then it parses it and adds the necessary header information (by calling out
  92  * to mime_get_elements()
  93  */
  94 function mime_parse_structure ($structure, $ent_id) {
  95
  96   $msg = new message();
  97   if ($structure{0} == '(') {
  98      $ent_id = mime_new_element_level($ent_id);
  99      $start = $end = -1;
 100      do {
 101         $start = $end+1;
 102         $end = mime_match_parenthesis ($start, $structure);
 103
 104         $element = substr($structure, $start+1, ($end - $start)-1);
 105         $ent_id = mime_increment_id ($ent_id);
 106         $newmsg = mime_parse_structure ($element, $ent_id);
 107         $msg->addEntity ($newmsg);
 108      } while ($structure{$end+1} == '(');
 109   } else {
 110      // parse the elements
 111      $msg = mime_get_element ($structure, $msg, $ent_id);
 112   }
 113   return $msg;
 114 }
 115
 116 /* Increments the element ID.  An element id can look like any of
 117  * the following:  1, 1.2, 4.3.2.4.1, etc.  This function increments
 118  * the last number of the element id, changing 1.2 to 1.3.
 119  */
 120 function mime_increment_id ($id) {
 121
 122     if (strpos($id, '.')) {
 123         $first = substr($id, 0, strrpos($id, '.'));
 124         $last = substr($id, strrpos($id, '.')+1);
 125         $last++;
 126         $new = $first . '.' .$last;
 127     } else {
 128         $new = $id + 1;
 129     }
 130
 131     return $new;
 132 }
 133
 134 /*
 135  * See comment for mime_increment_id().
 136  * This adds another level on to the entity_id changing 1.3 to 1.3.0
 137  * NOTE:  1.3.0 is not a valid element ID.  It MUST be incremented
 138  *        before it can be used.  I left it this way so as not to have
 139  *        to make a special case if it is the first entity_id.  It
 140  *        always increments it, and that works fine.
 141  */
 142 function mime_new_element_level ($id) {
 143
 144     if (!$id) {
 145         $id = 0;
 146     } else {
 147         $id = $id . '.0';
 148     }
 149
 150     return( $id );
 151 }
 152
 153 function mime_get_element (&$structure, $msg, $ent_id) {
 154
 155   $elem_num = 1;
 156   $msg->header = new msg_header();
 157   $msg->header->entity_id = $ent_id;
 158   $properties = array();
 159
 160   while (strlen($structure) > 0) {
 161      $structure = trim($structure);
 162      $char = $structure{0};
 163
 164      if (strtolower(substr($structure, 0, 3)) == 'nil') {
 165         $text = '';
 166         $structure = substr($structure, 3);
 167      } else if ($char == '"') {
 168         // loop through until we find the matching quote, and return that as a string
 169         $pos = 1;
 170         $text = '';
 171         while ( ($char = $structure{$pos} ) <> '"' && $pos < strlen($structure)) {
 172            $text .= $char;
 173            $pos++;
 174         }
 175         $structure = substr($structure, strlen($text) + 2);
 176      } else if ($char == '(') {
 177         // comment me
 178         $end = mime_match_parenthesis (0, $structure);
 179         $sub = substr($structure, 1, $end-1);
 180         $properties = mime_get_props($properties, $sub);
 181         $structure = substr($structure, strlen($sub) + 2);
 182      } else {
 183         // loop through until we find a space or an end parenthesis
 184         $pos = 0;
 185         $char = $structure{$pos};
 186         $text = '';
 187         while ($char != ' ' && $char != ')' && $pos < strlen($structure)) {
 188            $text .= $char;
 189            $pos++;
 190            $char = $structure{$pos};
 191         }
 192         $structure = substr($structure, strlen($text));
 193      }
 194
 195      // This is where all the text parts get put into the header
 196      switch ($elem_num) {
 197         case 1:
 198            $msg->header->type0 = strtolower($text);
 199            break;
 200         case 2:
 201            $msg->header->type1 = strtolower($text);
 202            break;
 203         case 4: // Id
 204            // Invisimail enclose images with <>
 205            $msg->header->id = str_replace( '<', '', str_replace( '>', '', $text ) );
 206            break;
 207         case 5:
 208            $msg->header->description = $text;
 209            break;
 210         case 6:
 211            $msg->header->encoding = strtolower($text);
 212            break;
 213         case 7:
 214            $msg->header->size = $text;
 215            break;
 216         default:
 217            if ($msg->header->type0 == 'text' && $elem_num == 8) {
 218               // This is a plain text message, so lets get the number of lines
 219               // that it contains.
 220               $msg->header->num_lines = $text;
 221
 222            } else if ($msg->header->type0 == 'message' && $msg->header->type1 == 'rfc822' && $elem_num == 8) {
 223               // This is an encapsulated message, so lets start all over again and
 224               // parse this message adding it on to the existing one.
 225               $structure = trim($structure);
 226               if ( $structure{0} == '(' ) {
 227                  $e = mime_match_parenthesis (0, $structure);
 228                  $structure = substr($structure, 0, $e);
 229                  $structure = substr($structure, 1);
 230                  $m = mime_parse_structure($structure, $msg->header->entity_id);
 231
 232                  // the following conditional is there to correct a bug that wasn't
 233                  // incrementing the entity IDs correctly because of the special case
 234                  // that message/rfc822 is.  This fixes it fine.
 235                  if (substr($structure, 1, 1) != '(')
 236                     $m->header->entity_id = mime_increment_id(mime_new_element_level($ent_id));
 237
 238                  // Now we'll go through and reformat the results.
 239                  if ($m->entities) {
 240                     for ($i=0; $i < count($m->entities); $i++) {
 241                        $msg->addEntity($m->entities[$i]);
 242                     }
 243                  } else {
 244                     $msg->addEntity($m);
 245                  }
 246                  $structure = "";
 247               }
 248            }
 249            break;
 250      }
 251      $elem_num++;
 252      $text = "";
 253   }
 254   // loop through the additional properties and put those in the various headers
 255   if ($msg->header->type0 != 'message') {
 256      for ($i=0; $i < count($properties); $i++) {
 257         $msg->header->{$properties[$i]['name']} = $properties[$i]['value'];
 258      }
 259   }
 260
 261   return $msg;
 262 }
 263
 264 /*
 265  * I did most of the MIME stuff yesterday (June 20, 2000), but I couldn't
 266  * figure out how to do this part, so I decided to go to bed.  I woke up
 267  * in the morning and had a flash of insight.  I went to the white-board
 268  * and scribbled it out, then spent a bit programming it, and this is the
 269  * result.  Nothing complicated, but I think my brain was fried yesterday.
 270  * Funny how that happens some times.
 271  *
 272  * This gets properties in a nested parenthesisized list.  For example,
 273  * this would get passed something like:  ("attachment" ("filename" "luke.tar.gz"))
 274  * This returns an array called $props with all paired up properties.
 275  * It ignores the "attachment" for now, maybe that should change later
 276  * down the road.  In this case, what is returned is:
 277  *    $props[0]["name"] = "filename";
 278  *    $props[0]["value"] = "luke.tar.gz";
 279  */
 280 function mime_get_props ($props, $structure) {
 281
 282   while (strlen($structure) > 0) {
 283      $structure = trim($structure);
 284      $char = $structure{0};
 285
 286      if ($char == '"') {
 287         $pos = 1;
 288         $tmp = '';
 289         while ( ( $char = $structure{$pos} ) != '"' &&
 290                 $pos < strlen($structure)) {
 291            $tmp .= $char;
 292            $pos++;
 293         }
 294         $structure = trim(substr($structure, strlen($tmp) + 2));
 295         $char = $structure{0};
 296
 297         if ($char == '"') {
 298            $pos = 1;
 299            $value = '';
 300            while ( ( $char = $structure{$pos} ) != '"' &&
 301                    $pos < strlen($structure) ) {
 302               $value .= $char;
 303               $pos++;
 304            }
 305            $structure = trim(substr($structure, strlen($tmp) + 2));
 306
 307            $k = count($props);
 308            $props[$k]['name'] = strtolower($tmp);
 309            $props[$k]['value'] = $value;
 310         } else if ($char == '(') {
 311            $end = mime_match_parenthesis (0, $structure);
 312            $sub = substr($structure, 1, $end-1);
 313        if (! isset($props))
 314            $props = array();
 315            $props = mime_get_props($props, $sub);
 316            $structure = substr($structure, strlen($sub) + 2);
 317         }
 318         return $props;
 319      } else if ($char == '(') {
 320         $end = mime_match_parenthesis (0, $structure);
 321         $sub = substr($structure, 1, $end-1);
 322         $props = mime_get_props($props, $sub);
 323         $structure = substr($structure, strlen($sub) + 2);
 324         return $props;
 325      } else {
 326         return $props;
 327      }
 328   }
 329 }
 330
 331 /*
 332  *  Matches parenthesis.  It will return the position of the matching
 333  *  parenthesis in $structure.  For instance, if $structure was:
 334  *     ("text" "plain" ("val1name", "1") nil ... )
 335  *     x                                         x
 336  *  then this would return 42 to match up those two.
 337  */
 338 function mime_match_parenthesis ($pos, $structure) {
 339
 340     $j = strlen( $structure );
 341
 342     // ignore all extra characters
 343     // If inside of a string, skip string -- Boundary IDs and other
 344     // things can have ) in them.
 345     if ( $structure{$pos} != '(' ) {
 346         return( $j );
 347     }
 348
 349     while ( $pos < $j ) {
 350         $pos++;
 351         if ($structure{$pos} == ')') {
 352             return $pos;
 353         } elseif ($structure{$pos} == '"') {
 354             $pos++;
 355             while ( $structure{$pos} != '"' &&
 356                     $pos < $j ) {
 357                if (substr($structure, $pos, 2) == '\\"') {
 358                   $pos++;
 359                } elseif (substr($structure, $pos, 2) == '\\\\') {
 360                   $pos++;
 361                }
 362                $pos++;
 363             }
 364         } elseif ( $structure{$pos} == '(' ) {
 365             $pos = mime_match_parenthesis ($pos, $structure);
 366         }
 367     }
 368     echo _("Error decoding mime structure.  Report this as a bug!") . '<br>';
 369     return( $pos );
 370 }
 371
 372 function mime_fetch_body($imap_stream, $id, $ent_id ) {
 373
 374     /*
 375      * do a bit of error correction.  If we couldn't find the entity id, just guess
 376      * that it is the first one.  That is usually the case anyway.
 377      */
 378     if (!$ent_id) {
 379         $ent_id = 1;
 380     }
 381
 382     $cmd = "FETCH $id BODY[$ent_id]";
 383     $data = sqimap_run_command ($imap_stream, $cmd, true, $response, $message);
 384
 385     do {
 386         $topline = array_shift( $data );
 387     } while( $topline && $topline == '*' && !preg_match( '/\\* [0-9] FETCH.*/i', $topline )) ;
 388     $wholemessage = implode('', $data);
 389     if (ereg('\\{([^\\}]*)\\}', $topline, $regs)) {
 390
 391         $ret = substr( $wholemessage, 0, $regs[1] );
 392         /*
 393             There is some information in the content info header that could be important
 394             in order to parse html messages. Let's get them here.
 395         */
 396         if ( $ret{0} == '<' ) {
 397             $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id.MIME]", true, $response, $message);
 398             $base = '';
 399             $k = 10;
 400             foreach( $data as $d ) {
 401                 if ( substr( $d, 0, 13 ) == 'Content-Base:' ) {
 402                     $j = strlen( $d );
 403                     $i = 13;
 404                     $base = '';
 405                     while ( $i < $j &&
 406                            ( !isNoSep( $d{$i} ) || $d{$i} == '"' )  )
 407                         $i++;
 408                     while ( $i < $j ) {
 409                         if ( isNoSep( $d{$i} ) )
 410                             $base .= $d{$i};
 411                         $i++;
 412                     }
 413                     $k = 0;
 414                 } elseif ( $k == 1 && !isnosep( $d{0} ) ) {
 415                     $base .= substr( $d, 1 );
 416                 }
 417                 $k++;
 418             }
 419             if ( $base <> '' ) {
 420                 $ret = "<base href=\"$base\">" . $ret;
 421             }
 422         }
 423     } else if (ereg('"([^"]*)"', $topline, $regs)) {
 424         $ret = $regs[1];
 425     } else {
 426         global $where, $what, $mailbox, $passed_id, $startMessage;
 427         $par = 'mailbox=' . urlencode($mailbox) . "&passed_id=$passed_id";
 428         if (isset($where) && isset($what)) {
 429             $par .= '&where='. urlencode($where) . "&what=" . urlencode($what);
 430         } else {
 431             $par .= "&startMessage=$startMessage&show_more=0";
 432         }
 433         $par .= '&response=' . urlencode($response) .
 434                 '&message=' . urlencode($message).
 435                 '&topline=' . urlencode($topline);
 436
 437         echo   '<tt><br>' .
 438                '<table width="80%"><tr>' .
 439                '<tr><td colspan=2>' .
 440                _("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!") .
 441                " <A HREF=\"../src/retrievalerror.php?$par\"><br>" .
 442                _("Submit message") . '</A><BR>&nbsp;' .
 443                '</td></tr>' .
 444                '<td><b>' . _("Command:") . "</td><td>$cmd</td></tr>" .
 445                '<td><b>' . _("Response:") . "</td><td>$response</td></tr>" .
 446                '<td><b>' . _("Message:") . "</td><td>$message</td></tr>" .
 447                '<td><b>' . _("FETCH line:") . "</td><td>$topline</td></tr>" .
 448                "</table><BR></tt></font><hr>";
 449
 450         $data = sqimap_run_command ($imap_stream, "FETCH $passed_id BODY[]", true, $response, $message);
 451         array_shift($data);
 452         $wholemessage = implode('', $data);
 453
 454         $ret = $wholemessage;
 455     }
 456     return( $ret );
 457 }
 458
 459 function mime_print_body_lines ($imap_stream, $id, $ent_id, $encoding) {
 460     // do a bit of error correction.  If we couldn't find the entity id, just guess
 461     // that it is the first one.  That is usually the case anyway.
 462     if (!$ent_id) {
 463         $ent_id = 1;
 464     }
 465     $sid = sqimap_session_id();
 466     // Don't kill the connection if the browser is over a dialup
 467     // and it would take over 30 seconds to download it.
 468
 469     // don´t call set_time_limit in safe mode.
 470     if (!ini_get("safe_mode")) {
 471         set_time_limit(0);
 472     }
 473
 474     fputs ($imap_stream, "$sid FETCH $id BODY[$ent_id]\r\n");
 475     $cnt = 0;
 476     $continue = true;
 477     $read = fgets ($imap_stream,4096);
 478     // This could be bad -- if the section has sqimap_session_id() . ' OK'
 479     // or similar, it will kill the download.
 480     while (!ereg("^".$sid." (OK|BAD|NO)(.*)$", $read, $regs)) {
 481       if (trim($read) == ')==') {
 482           $read1 = $read;
 483           $read = fgets ($imap_stream,4096);
 484           if (ereg("^".$sid." (OK|BAD|NO)(.*)$", $read, $regs)) {
 485               return;
 486           } else {
 487               echo decodeBody($read1, $encoding) .
 488                    decodeBody($read, $encoding);
 489           }
 490       } else if ($cnt) {
 491           echo decodeBody($read, $encoding);
 492       }
 493       $read = fgets ($imap_stream,4096);
 494       $cnt++;
 495     }
 496 }
 497
 498 /* -[ END MIME DECODING ]----------------------------------------------------------- */
 499
 500
 501
 502 /* This is the first function called.  It decides if this is a multipart
 503    message or if it should be handled as a single entity
 504  */
 505 function decodeMime ($imap_stream, &$header) {
 506     global $username, $key, $imapServerAddress, $imapPort;
 507     return mime_structure ($imap_stream, $header);
 508 }
 509
 510 // This is here for debugging purposese.  It will print out a list
 511 // of all the entity IDs that are in the $message object.
 512 /*
 513 function listEntities ($message) {
 514 if ($message) {
 515  if ($message->header->entity_id)
 516  echo "<tt>" . $message->header->entity_id . ' : ' . $message->header->type0 . '/' . $message->header->type1 . '<br>';
 517  for ($i = 0; $message->entities[$i]; $i++) {
 518     $msg = listEntities($message->entities[$i], $ent_id);
 519     if ($msg)
 520        return $msg;
 521  }
 522 }
 523 }
 524 */
 525
 526 /* returns a $message object for a particular entity id */
 527 function getEntity ($message, $ent_id) {
 528     if ($message) {
 529         if ($message->header->entity_id == $ent_id && strlen($ent_id) == strlen($message->header->entity_id)) {
 530             return $message;
 531         } else {
 532             for ($i = 0; isset($message->entities[$i]); $i++) {
 533                 $msg = getEntity ($message->entities[$i], $ent_id);
 534                 if ($msg) {
 535                     return $msg;
 536                 }
 537             }
 538         }
 539     }
 540 }
 541
 542 /*
 543  * figures out what entity to display and returns the $message object
 544  * for that entity.
 545  */
 546 function findDisplayEntity ($message, $textOnly = 1)   {
 547     global $show_html_default;
 548
 549     $entity = 0;
 550
 551     if ($message) {
 552         if ( $message->header->type0 == 'multipart' &&
 553              ( $message->header->type1 == 'alternative' ||
 554                $message->header->type1 == 'related' ) &&
 555              $show_html_default && ! $textOnly ) {
 556             $entity = findDisplayEntityHTML($message);
 557         }
 558
 559         // Show text/plain or text/html -- the first one we find.
 560         if ( $entity == 0 &&
 561              $message->header->type0 == 'text' &&
 562              ( $message->header->type1 == 'plain' ||
 563                $message->header->type1 == 'html' ) &&
 564              isset($message->header->entity_id) ) {
 565             $entity = $message->header->entity_id;
 566         }
 567
 568         $i = 0;
 569         while ($entity == 0 && isset($message->entities[$i]) ) {
 570             $entity = findDisplayEntity($message->entities[$i], $textOnly);
 571             $i++;
 572         }
 573     }
 574
 575     return( $entity );
 576 }
 577
 578 /* Shows the HTML version */
 579 function findDisplayEntityHTML ($message) {
 580
 581     if ( $message->header->type0 == 'text' &&
 582          $message->header->type1 == 'html' &&
 583          isset($message->header->entity_id)) {
 584         return $message->header->entity_id;
 585     }
 586     for ($i = 0; isset($message->entities[$i]); $i ++) {
 587         $entity = findDisplayEntityHTML($message->entities[$i]);
 588         if ($entity != 0) {
 589             return $entity;
 590         }
 591     }
 592
 593     return 0;
 594 }
 595
 596 /* This returns a parsed string called $body. That string can then
 597 be displayed as the actual message in the HTML. It contains
 598 everything needed, including HTML Tags, Attachments at the
 599 bottom, etc.
 600 */
 601 function formatBody($imap_stream, $message, $color, $wrap_at) {
 602     // this if statement checks for the entity to show as the
 603     // primary message. To add more of them, just put them in the
 604     // order that is their priority.
 605     global $startMessage, $username, $key, $imapServerAddress, $imapPort,
 606            $show_html_default;
 607
 608     $id = $message->header->id;
 609     $urlmailbox = urlencode($message->header->mailbox);
 610
 611     // Get the right entity and redefine message to be this entity
 612     // Pass the 0 to mean that we want the 'best' viewable one
 613     $ent_num = findDisplayEntity ($message, 0);
 614     $body_message = getEntity($message, $ent_num);
 615     if (($body_message->header->type0 == 'text') ||
 616         ($body_message->header->type0 == 'rfc822')) {
 617
 618         $body = mime_fetch_body ($imap_stream, $id, $ent_num);
 619         $body = decodeBody($body, $body_message->header->encoding);
 620         $hookResults = do_hook("message_body", $body);
 621         $body = $hookResults[1];
 622
 623         // If there are other types that shouldn't be formatted, add
 624         // them here
 625         if ($body_message->header->type1 == 'html') {
 626             if ( $show_html_default <> 1 ) {
 627                 $body = strip_tags( $body );
 628                 translateText($body, $wrap_at, $body_message->header->charset);
 629             } else {
 630                 $body = MagicHTML( $body, $id );
 631             }
 632         } else {
 633             translateText($body, $wrap_at, $body_message->header->charset);
 634         }
 635
 636         $body .= "<SMALL><CENTER><A HREF=\"../src/download.php?absolute_dl=true&passed_id=$id&passed_ent_id=$ent_num&mailbox=$urlmailbox&showHeaders=1\">". _("Download this as a file") ."</A></CENTER><BR></SMALL>";
 637
 638         /** Display the ATTACHMENTS: message if there's more than one part **/
 639         $body .= "</TD></TR></TABLE>";
 640         if (isset($message->entities[0])) {
 641             $body .= formatAttachments ($message, $ent_num, $message->header->mailbox, $id);
 642         }
 643         $body .= "</TD></TR></TABLE>";
 644     } else {
 645         $body = formatAttachments ($message, -1, $message->header->mailbox, $id);
 646     }
 647     return ($body);
 648 }
 649
 650 /*
 651  * A recursive function that returns a list of attachments with links
 652  * to where to download these attachments
 653  */
 654 function formatAttachments($message, $ent_id, $mailbox, $id) {
 655     global $where, $what;
 656     global $startMessage, $color;
 657     static $ShownHTML = 0;
 658
 659     $body = '';
 660     if ($ShownHTML == 0) {
 661
 662         $ShownHTML = 1;
 663         $body .= "<TABLE WIDTH=\"100%\" CELLSPACING=0 CELLPADDING=2 BORDER=0 BGCOLOR=\"$color[0]\"><TR>\n" .
 664                 "<TH ALIGN=\"left\" BGCOLOR=\"$color[9]\"><B>\n" .
 665                 _("Attachments") . ':' .
 666                 "</B></TH></TR><TR><TD>\n" .
 667                 "<TABLE CELLSPACING=0 CELLPADDING=1 BORDER=0>\n" .
 668                 formatAttachments($message, $ent_id, $mailbox, $id) .
 669                 "</TABLE></TD></TR></TABLE>";
 670
 671     } else if ($message) {
 672
 673         if (!$message->entities) {
 674
 675             $type0 = strtolower($message->header->type0);
 676             $type1 = strtolower($message->header->type1);
 677             $name = decodeHeader($message->header->name);
 678
 679             if ($message->header->entity_id != $ent_id) {
 680             $filename = decodeHeader($message->header->filename);
 681             if (trim($filename) == '') {
 682                 if (trim($name) == '') {
 683                     if ( trim( $message->header->id ) == '' )
 684                         $display_filename = 'untitled-[' . $message->header->entity_id . ']' ;
 685                     else
 686                         $display_filename = 'cid: ' . $message->header->id;
 687                     // $display_filename = 'untitled-[' . $message->header->entity_id . ']' ;
 688                 } else {
 689                     $display_filename = $name;
 690                     $filename = $name;
 691                 }
 692             } else {
 693                 $display_filename = $filename;
 694             }
 695
 696             $urlMailbox = urlencode($mailbox);
 697             $ent = urlencode($message->header->entity_id);
 698
 699             $DefaultLink =
 700                 "../src/download.php?startMessage=$startMessage&passed_id=$id&mailbox=$urlMailbox&passed_ent_id=$ent";
 701             if ($where && $what) {
 702                 $DefaultLink .= '&where=' . urlencode($where) . '&what=' . urlencode($what);
 703             }
 704             $Links['download link']['text'] = _("download");
 705             $Links['download link']['href'] =
 706                 "../src/download.php?absolute_dl=true&passed_id=$id&mailbox=$urlMailbox&passed_ent_id=$ent";
 707             $ImageURL = '';
 708
 709             /* this executes the attachment hook with a specific MIME-type.
 710                 * if that doens't have results, it tries if there's a rule
 711                 * for a more generic type. */
 712             $HookResults = do_hook("attachment $type0/$type1", $Links,
 713                 $startMessage, $id, $urlMailbox, $ent, $DefaultLink,
 714                 $display_filename, $where, $what);
 715             if(count($HookResults[1]) <= 1) {
 716                 $HookResults = do_hook("attachment $type0/*", $Links,
 717                 $startMessage, $id, $urlMailbox, $ent, $DefaultLink,
 718                 $display_filename, $where, $what);
 719             }
 720
 721             $Links = $HookResults[1];
 722             $DefaultLink = $HookResults[6];
 723
 724             $body .= '<TR><TD>&nbsp;&nbsp;</TD><TD>' .
 725                         "<A HREF=\"$DefaultLink\">$display_filename</A>&nbsp;</TD>" .
 726                         '<TD><SMALL><b>' . show_readable_size($message->header->size) .
 727                         '</b>&nbsp;&nbsp;</small></TD>' .
 728                         "<TD><SMALL>[ $type0/$type1 ]&nbsp;</SMALL></TD>" .
 729                         '<TD><SMALL>';
 730             if ($message->header->description) {
 731                 $body .= '<b>' . htmlspecialchars(_($message->header->description)) . '</b>';
 732             }
 733             $body .= '</SMALL></TD><TD><SMALL>&nbsp;';
 734
 735
 736             $SkipSpaces = 1;
 737             foreach ($Links as $Val) {
 738                 if ($SkipSpaces) {
 739                     $SkipSpaces = 0;
 740                 } else {
 741                     $body .= '&nbsp;&nbsp;|&nbsp;&nbsp;';
 742                 }
 743                 $body .= '<a href="' . $Val['href'] . '">' .  $Val['text'] . '</a>';
 744             }
 745
 746             unset($Links);
 747
 748             $body .= "</SMALL></TD></TR>\n";
 749             }
 750         } else {
 751             for ($i = 0; $i < count($message->entities); $i++) {
 752                 $body .= formatAttachments($message->entities[$i], $ent_id, $mailbox, $id);
 753             }
 754         }
 755     }
 756     return( $body );
 757 }
 758
 759
 760 /** this function decodes the body depending on the encoding type. **/
 761 function decodeBody($body, $encoding) {
 762   $body = str_replace("\r\n", "\n", $body);
 763   $encoding = strtolower($encoding);
 764
 765   global $show_html_default;
 766
 767   if ($encoding == 'quoted-printable') {
 768      $body = quoted_printable_decode($body);
 769
 770
 771      while (ereg("=\n", $body))
 772         $body = ereg_replace ("=\n", "", $body);
 773
 774   } else if ($encoding == 'base64') {
 775      $body = base64_decode($body);
 776   }
 777
 778   // All other encodings are returned raw.
 779   return $body;
 780 }
 781
 782 /*
 783  * This functions decode strings that is encoded according to
 784  * RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
 785  */
 786 function decodeHeader ($string, $utfencode=true) {
 787
 788 if ( is_array( $string ) ) {
 789     $string = implode("\n", $string );
 790 }
 791
 792 if (eregi('=\\?([^?]+)\\?(q|b)\\?([^?]+)\\?=',
 793             $string, $res)) {
 794     if (ucfirst($res[2]) == 'B') {
 795         $replace = base64_decode($res[3]);
 796     } else {
 797         $replace = str_replace('_', ' ', $res[3]);
 798         // Convert lowercase Quoted Printable to uppercase for
 799         // quoted_printable_decode to understand it.
 800         while (ereg("(=(([0-9][abcdef])|([abcdef][0-9])|([abcdef][abcdef])))",
 801                $replace, $res)) {
 802             $replace = str_replace($res[1], strtoupper($res[1]), $replace);
 803         }
 804         $replace = quoted_printable_decode($replace);
 805     }
 806     /* Only encode into entities by default. Some places
 807         don't need the encoding, like the compose form. */
 808     if ($utfencode){
 809         $replace = charset_decode ($res[1], $replace);
 810     }
 811
 812     // Remove the name of the character set.
 813     $string = eregi_replace ('=\\?([^?]+)\\?(q|b)\\?([^?]+)\\?=',
 814               $replace, $string);
 815
 816     // In case there should be more encoding in the string: recurse
 817     $string = decodeHeader($string);
 818 }
 819
 820 return ($string);
 821 }
 822
 823 /*
 824  * Encode a string according to RFC 1522 for use in headers if it
 825  * contains 8-bit characters or anything that looks like it should
 826  * be encoded.
 827  */
 828 function encodeHeader ($string) {
 829     global $default_charset;
 830
 831     // Encode only if the string contains 8-bit characters or =?
 832     $j = strlen( $string  );
 833     $l = strstr($string, '=?');         // Must be encoded ?
 834     $ret = '';
 835     for( $i=0; $i < $j; ++$i) {
 836         switch( $string{$i} ) {
 837            case '=':
 838           $ret .= '=3D';
 839           break;
 840         case '?':
 841           $ret .= '=3F';
 842           break;
 843         case '_':
 844           $ret .= '=5F';
 845           break;
 846         case ' ':
 847           $ret .= '_';
 848           break;
 849         default:
 850           $k = ord( $string{$i} );
 851           if ( $k > 126 ) {
 852              $ret .= sprintf("=%02X", $k);
 853              $l = TRUE;
 854           } else
 855              $ret .= $string{$i};
 856         }
 857     }
 858
 859     if ( $l ) {
 860         $string = "=?$default_charset?Q?$ret?=";
 861     }
 862
 863     return( $string );
 864 }
 865
 866 /*
 867     Strips dangerous tags from html messages.
 868 */
 869 function MagicHTML( $body, $id ) {
 870
 871     global $message, $HTTP_SERVER_VARS,
 872            $attachment_common_show_images;
 873
 874     $attachment_common_show_images =
 875                      FALSE; // Don't display attached images in HTML mode
 876     $j = strlen( $body );   // Legnth of the HTML
 877     $ret = '';              // Returned string
 878     $bgcolor = '#ffffff';   // Background style color (defaults to white)
 879     $textcolor = '#000000'; // Foreground style color (defaults to black)
 880     $leftmargin = '';       // Left margin style
 881     $title = '';            // HTML title if any
 882
 883     $i = 0;
 884     while ( $i < $j ) {
 885         if ( $body{$i} == '<' ) {
 886             $pos = $i + 1;
 887             $tag = '';
 888             while ($body{$pos} == ' ' || $body{$pos} == "\t" ||
 889                    $body{$pos} == "\n" ) {
 890                 $pos ++;
 891             }
 892             while (strlen($tag) < 4 && $body{$pos} != ' ' &&
 893                    $body{$pos} != "\t" && $body{$pos} != "\n" &&
 894                    $pos < $j ) {
 895                 $tag .= $body{$pos};
 896                 $pos ++;
 897             }
 898             switch( strtoupper( $tag ) ) {
 899             // Strips the entire tag and contents
 900             case 'APPL':
 901             case 'EMBB':
 902             case 'FRAM':
 903             case 'SCRI':
 904             case 'OBJE':
 905                 $etg = '/' . $tag;
 906                 while ( $body{$i+1}.$body{$i+2}.$body{$i+3}.$body{$i+4}.$body{$i+5} <> $etg  &&
 907                        $i < $j  ) $i++;
 908                 while ( $i < $j && $body{++$i} <> '>' );
 909                 // $ret .= "<!-- $tag removed -->";
 910                 break;
 911             // Substitute Title
 912             case 'TITL':
 913                 $i += 5;
 914                 while ( $body{$i} <> '>' &&  // </title>
 915                        $i < $j )
 916                         $i++;
 917                 $i++;
 918                 $title = '';
 919                 while ( $body{$i} <> '<' &&  // </title>
 920                        $i < $j ) {
 921                     $title .= $body{$i};
 922                     $i++;
 923                 }
 924                 $i += 7;
 925                 break;
 926             // Destroy these tags
 927             case 'HTML':
 928             case 'HEAD':
 929             case '/HTM':
 930             case '/HEA':
 931             case '!DOC':
 932             case 'META':
 933             //case 'DIV ':
 934             //case '/DIV':
 935             case '!-- ':
 936                 $i += 4;
 937                 while ( $body{$i}  <> '>' &&
 938                        $i < $j )
 939                     $i++;
 940                 // $i++;
 941                 break;
 942             case 'STYL':
 943                 $i += 5;
 944                 while ( $body{$i} <> '>' &&  // </title>
 945                        $i < $j )
 946                         $i++;
 947                 $i++;
 948                 // We parse the style to look for interesting stuff
 949                 $styleblk = '';
 950                 while ( $body{$i} <> '>' &&
 951                        $i < $j ) {
 952                     // First we get the name of the style
 953                     $style = '';
 954                     while ( $body{$i} <> '>' &&
 955                            $body{$i} <> '<' &&
 956                            $body{$i} <> '{' &&
 957                            $i < $j ) {
 958                        if ( isnoSep( $body{$i} ) )
 959                            $style .= $body{$i};
 960                        $i++;
 961                     }
 962                     stripComments( $i, $j, $body );
 963                     $style = strtoupper( trim( $style ) );
 964                     if ( $style == 'BODY' ) {
 965                         // Next we look into the definitions of the body style
 966                         while ( $body{$i} <> '>' &&
 967                                $body{$i} <> '}' &&
 968                                $i < $j ) {
 969                             // We look for the background color if any.
 970                             if ( substr( $body, $i, 17 ) == 'BACKGROUND-COLOR:' ) {
 971                                 $i += 17;
 972                                 $bgcolor = getStyleData( $i, $j, $body );
 973                             } elseif ( substr( $body, $i, 12 ) == 'MARGIN-LEFT:' ) {
 974                                 $i += 12;
 975                                 $leftmargin = getStyleData( $i, $j, $body );
 976                             }
 977                             $i++;
 978                         }
 979                     } else {
 980                         // Other style are mantained
 981                         $styleblk .= "$style ";
 982                         while ( $body{$i} <> '>' &&
 983                                $body{$i} <> '<' &&
 984                                $body{$i} <> '}' &&
 985                                $i < $j ) {
 986                             $styleblk .= $body{$i};
 987                             $i++;
 988                         }
 989                         $styleblk .= $body{$i};
 990                     }
 991                     stripComments( $i, $j, $body );
 992                     if ( $body{$i} <> '>' )
 993                         $i++;
 994                 }
 995                 if ( $styleblk <> '' )
 996                     $ret .= "<style>$styleblk";
 997                 break;
 998             case 'BODY':
 999                 if ( $title <> '' )
1000                     $ret .= '<b>' . _("Title:") . " </b>$title<br>\n";
1001                 $ret .= "<TABLE";
1002                 $i += 5;
1003                 if (! isset($base)) {
1004                     $base = '';
1005                 }
1006                 $ret .= stripEvent( $i, $j, $body, $id, $base );
1007                 $ret .= " bgcolor=$bgcolor width=\"100%\"><tr>";
1008                 if ( $leftmargin <> '' )
1009                     $ret .= "<td width=$leftmargin>&nbsp;</td>";
1010                 $ret .= '<td>';
1011                 if (strtolower($bgcolor) == 'ffffff' ||
1012                     strtolower($bgcolor) == '#ffffff')
1013                     $ret .= '<font color=#000000>';
1014                 break;
1015             case 'BASE':
1016                 $i += 5;
1017                 $base = '';
1018                 while ( !isNoSep( $body{$i} ) &&
1019                        $i < $j ) {
1020                         $i++;
1021                 }
1022                 if ( strcasecmp( substr( $base, 0, 4 ), 'href'  ) ) {
1023                         $i += 5;
1024                         while ( !isNoSep( $body{$i} ) &&
1025                                $i < $j ) {
1026                                 $i++;
1027                         }
1028                         while ( $body{$i} <> '>' &&
1029                                $i < $j ) {
1030                             if ( $body{$i} <> '"' ) {
1031                                 $base .= $body{$i};
1032                             }
1033                             $i++;
1034                         }
1035                         // Debuging $ret .= "<!-- base == $base -->";
1036                         if ( strcasecmp( substr( $base, 0, 4 ), 'file' ) <> 0 ) {
1037                             $ret .= "\n<BASE HREF=\"$base\">\n";
1038                         }
1039                 }
1040                 break;
1041             case '/BOD':
1042                 $ret .= '</font></td></tr></TABLE>';
1043                 $i += 6;
1044                 break;
1045             default:
1046                 // Following tags can contain some event handler, lets search it
1047                 stripComments( $i, $j, $body );
1048                 if (! isset($base)) {
1049                    $base = '';
1050                 }
1051                 $ret .= stripEvent( $i, $j, $body, $id, $base ) . '>';
1052                         // $ret .= "<!-- $tag detected -->";
1053             }
1054         } else {
1055             $ret .= $body{$i};
1056         }
1057     $i++;
1058     }
1059
1060 return( "\n\n<!-- HTML Output ahead -->\n" .
1061         $ret .
1062         "\n<!-- END of HTML Output --><base href=\"".
1063         get_location() . '/'.
1064         "\">\n\n" );
1065 }
1066
1067 function isNoSep( $char ) {
1068
1069     switch( $char ) {
1070     case ' ':
1071     case "\n":
1072     case "\t":
1073     case "\r":
1074     case '>':
1075     case '"':
1076         return( FALSE );
1077         break;
1078     default:
1079         return( TRUE );
1080     }
1081
1082 }
1083
1084 /*
1085   The following function is usefull to remove extra data that can cause
1086   html not to display properly. Especialy with MS stuff.
1087 */
1088
1089 function stripComments( &$i, $j, &$body ) {
1090
1091     while ( $body{$i}.$body{$i+1}.$body{$i+2}.$body{$i+3} == '<!--' &&
1092            $i < $j ) {
1093         $i += 5;
1094         while ( $body{$i-2}.$body{$i-1}.$body{$i} <> '-->' &&
1095                $i < $j )
1096             $i++;
1097         $i++;
1098     }
1099
1100     return;
1101
1102 }
1103
1104 /* Gets the style data of a specific style */
1105
1106 function getStyleData( &$i, $j, &$body ) {
1107
1108     // We skip spaces
1109     while ( $body{$i} <> '>' && !isNoSep( $body{$i} ) &&
1110            $i < $j ) {
1111         $i++;
1112     }
1113     // And get the color
1114     $ret = '';
1115     while ( isNoSep( $body{$i} ) &&
1116            $i < $j ) {
1117         $ret .= $body{$i};
1118         $i++;
1119     }
1120
1121     return( $ret );
1122 }
1123
1124 /*
1125 Private function for strip_dangerous_tag. Look for event based coded and "remove" it
1126 change on with no (onload -> noload)
1127 */
1128
1129 function stripEvent( &$i, $j, &$body, $id, $base ) {
1130
1131     global $message, $base_uri;
1132
1133     $ret = '';
1134
1135     while ( $body{$i} <> '>' &&
1136            $i < $j ) {
1137         $etg = strtolower($body{$i}.$body{$i+1}.$body{$i+2});
1138         switch( $etg ) {
1139         case 'src':
1140             // This is probably a src specification
1141             $k = $i + 3;
1142             while( !isNoSep( $body{$k} )) {
1143                 $k++;
1144             }
1145             if ( $body{$k} == '=' ) {
1146                 /* It is indeed */
1147                 $k++;
1148                 while( !isNoSep( $body{$k} ) &&
1149                        $k < $j ) {
1150                     $k++;
1151                 }
1152                 $src = '';
1153                 while ( $body{$k} <> '>' && isNoSep( $body{$k} ) &&
1154                        $k < $j ) {
1155                     $src .= $body{$k};
1156                     $k++;
1157                 }
1158                 while( !isNoSep( $body{$k} ) &&
1159                        $k < $j ) {
1160                     $k++;
1161                 }
1162                 if ( strtolower( substr( $src, 0, 4 ) ) == 'cid:' ) {
1163                     $src = substr( $src, 4 );
1164                     $src = "../src/download.php?absolute_dl=true&passed_id=$id&mailbox=" .
1165                            urlencode( $message->header->mailbox ) .
1166                            "&passed_ent_id=" . find_ent_id( $src, $message );
1167                 } else if ( strtolower( substr( $src, 0, 4 ) ) <> 'http' ||
1168                             stristr( $src, $base_uri ) ) {
1169                     /* Javascript and local urls goes out */
1170                     $src = '../images/' . _("sec_remove_eng.png");
1171                 }
1172                 $ret .= 'src="' . $src . '" ';
1173                 $i = $k - 2;
1174             } else {
1175                 $ret .= 'src';
1176                 $i = $i + 3;
1177             }
1178
1179             break;
1180         case '../':
1181             // Retrolinks are not allowed without a base because they mess with SM security
1182             if ( $base == '' ) {
1183                     $i += 2;
1184             } else {
1185                     $ret .= '.';
1186             }
1187             break;
1188         case 'cid':
1189             // Internal link
1190             $k = $i-1;
1191             if ( $body{$i+3} == ':') {
1192                 $i +=4;
1193                 $name = '';
1194                 while ( isNoSep( $body{$i} ) &&
1195                        $i < $j  ) {
1196                     $name .= $body{$i++};
1197                 }
1198                 if ( $name <> '' ) {
1199                     $ret .= "../src/download.php?absolute_dl=true&passed_id=$id&mailbox=" .
1200                                 urlencode( $message->header->mailbox ) .
1201                                 "&passed_ent_id=" . find_ent_id( $name, $message );
1202                     if ( $body{$k} == '"' )
1203                         $ret .= '" ';
1204                     else
1205                         $ret .= ' ';
1206                 }
1207                 if ( $body{$i} == '>' )
1208                     $i -= 1;
1209             }
1210             break;
1211         case ' on':
1212         case "\non":
1213         case "\ron":
1214         case "\ton":
1215             $ret .= ' no';
1216             $i += 2;
1217             break;
1218         case 'pt:':
1219             if ( strcasecmp( $body{$i-4}.$body{$i-3}.$body{$i-2}.$body{$i-1}.$body{$i}.$body{$i+1}.$body{$i+2}, 'script:') == 0 ) {
1220                 $ret .= '_no/';
1221             } else {
1222                 $ret .= $etg;
1223             }
1224             $i += 2;
1225             break;
1226         default:
1227             $ret .= $body{$i};
1228         }
1229         $i++;
1230     }
1231     return( $ret );
1232 }
1233
1234
1235 /* This function trys to locate the entity_id of a specific mime element */
1236
1237 function find_ent_id( $id, $message ) {
1238
1239     $ret = '';
1240     for ($i=0; $ret == '' && $i < count($message->entities); $i++) {
1241
1242         if ( $message->entities[$i]->header->entity_id == '' ) {
1243             $ret = find_ent_id( $id, $message->entities[$i] );
1244         } else {
1245             if ( strcasecmp( $message->entities[$i]->header->id, $id ) == 0 )
1246                 $ret = $message->entities[$i]->header->entity_id;
1247         }
1248
1249     }
1250
1251     return( $ret );
1252
1253 }
1254 ?>