File Source for mime.php

<?php
/**
* mime.php
*
* This contains the functions necessary to detect and decode MIME
* messages.
*
* @copyright 1999-2020 The SquirrelMail Project Team
* @license http://opensource.org/licenses/gpl-license.php GNU Public License
* @version $Id: mime.php 14840 2020-01-07 07:42:38Z pdontthink $
* @package squirrelmail
*/
/** The typical includes... */
require_once(SM_PATH . 'functions/imap.php');
require_once(SM_PATH . 'functions/attachment_common.php');
/* -------------------------------------------------------------------------- */
/* MIME DECODING */
/* -------------------------------------------------------------------------- */
/**
* Get the MIME structure
*
* This function gets the structure of a message and stores it in the "message" class.
* It will return this object for use with all relevant header information and
* fully parsed into the standard "message" object format.
*/
function mime_structure ($bodystructure, $flags=array()) {
/* Isolate the body structure and remove beginning and end parenthesis. */
$read = trim(substr ($bodystructure, strpos(strtolower($bodystructure), 'bodystructure') + 13));
$read = trim(substr ($read, 0, -1));
$i = 0;
$msg = Message::parseStructure($read,$i);
if (!is_object($msg)) {
include_once(SM_PATH . 'functions/display_messages.php');
global $color, $mailbox;
/* removed urldecode because $_GET is auto urldecoded ??? */
displayPageHeader( $color, $mailbox );
echo "<body text=\"$color[8]\" bgcolor=\"$color[4]\" link=\"$color[7]\" vlink=\"$color[7]\" alink=\"$color[7]\">\n\n" .
'<center>';
$errormessage = _("SquirrelMail could not decode the bodystructure of the message");
$errormessage .= '<br />'._("The bodystructure provided by your IMAP server:").'<br /><br />';
$errormessage .= '<table><tr><td>' . sm_encode_html_special_chars($read) . '</td></tr></table>';
plain_error_message( $errormessage, $color );
echo '</body></html>';
exit;
}
if (count($flags)) {
foreach ($flags as $flag) {
$char = strtoupper($flag{1});
switch ($char) {
case 'S':
if (strtolower($flag) == '\\seen') {
$msg->is_seen = true;
}
break;
case 'A':
if (strtolower($flag) == '\\answered') {
$msg->is_answered = true;
}
break;
case 'D':
if (strtolower($flag) == '\\deleted') {
$msg->is_deleted = true;
}
break;
case 'F':
if (strtolower($flag) == '\\flagged') {
$msg->is_flagged = true;
}
break;
case 'M':
if (strtolower($flag) == '$mdnsent') {
$msg->is_mdnsent = true;
}
break;
default:
break;
}
}
}
// listEntities($msg);
return $msg;
}
/* This starts the parsing of a particular structure. It is called recursively,
* so it can be passed different structures. It returns an object of type
* $message.
* First, it checks to see if it is a multipart message. If it is, then it
* handles that as it sees is necessary. If it is just a regular entity,
* then it parses it and adds the necessary header information (by calling out
* to mime_get_elements()
*/
function mime_fetch_body($imap_stream, $id, $ent_id=1, $fetch_size=0) {
global $uid_support;
/* Do a bit of error correction. If we couldn't find the entity id, just guess
* that it is the first one. That is usually the case anyway.
*/
if (!$ent_id) {
$cmd = "FETCH $id BODY[]";
} else {
$cmd = "FETCH $id BODY[$ent_id]";
}
if ($fetch_size!=0) $cmd .= "<0.$fetch_size>";
$data = sqimap_run_command ($imap_stream, $cmd, true, $response, $message, $uid_support);
do {
$topline = trim(array_shift($data));
} while($topline && ($topline[0] == '*') && !preg_match('/\* [0-9]+ FETCH .*BODY.*/i', $topline)) ;
// Matching with "BODY" above is difficult: in most cases "FETCH \(BODY" would work
// but some servers may put other things in the same result, perhaps something such
// as "* 23 FETCH (FLAGS (\Seen) BODY[1] {174}". There is some small chance that
// if the character sequence "BODY" appears in a response where it isn't actually
// a FETCH response data item name, the current regex will break things. The better
// way to do this would be to parse the response correctly and not use a regex.
$wholemessage = implode('', $data);
if (preg_match('/\{([^\}]*)\}/', $topline, $regs)) {
$ret = substr($wholemessage, 0, $regs[1]);
/* There is some information in the content info header that could be important
* in order to parse html messages. Let's get them here.
*/
// if ($ret{0} == '<') {
// $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id.MIME]", true, $response, $message, $uid_support);
// }
} else if (preg_match('/"([^"]*)"/', $topline, $regs)) {
$ret = $regs[1];
} else if ((stristr($topline, 'nil') !== false) && (empty($wholemessage))) {
$ret = $wholemessage;
} else {
global $where, $what, $mailbox, $passed_id, $startMessage;
$par = 'mailbox=' . urlencode($mailbox) . '&passed_id=' . $passed_id;
if (isset($where) && isset($what)) {
$par .= '&where=' . urlencode($where) . '&what=' . urlencode($what);
} else {
$par .= '&startMessage=' . $startMessage . '&show_more=0';
}
$par .= '&response=' . urlencode($response) .
'&message=' . urlencode($message) .
'&topline=' . urlencode($topline);
echo '<tt><br />' .
'<table width="80%"><tr>' .
'<tr><td colspan="2">' .
_("Body retrieval error. The reason for this is most probably that the message is malformed.") .
'</td></tr>' .
'<tr><td><b>' . _("Command:") . "</td><td>$cmd</td></tr>" .
'<tr><td><b>' . _("Response:") . "</td><td>$response</td></tr>" .
'<tr><td><b>' . _("Message:") . "</td><td>$message</td></tr>" .
'<tr><td><b>' . _("FETCH line:") . "</td><td>$topline</td></tr>" .
"</table><br /></tt></font><hr />";
$data = sqimap_run_command ($imap_stream, "FETCH $passed_id BODY[]", true, $response, $message, $uid_support);
array_shift($data);
$wholemessage = implode('', $data);
$ret = $wholemessage;
}
return $ret;
}
function mime_print_body_lines ($imap_stream, $id, $ent_id=1, $encoding, $rStream='php://stdout') {
global $uid_support;
/* Don't kill the connection if the browser is over a dialup
* and it would take over 30 seconds to download it.
* Don't call set_time_limit in safe mode.
*/
if (!ini_get('safe_mode')) {
set_time_limit(0);
}
/* in case of base64 encoded attachments, do not buffer them.
Instead, echo the decoded attachment directly to screen */
if (strtolower($encoding) == 'base64') {
if (!$ent_id) {
$query = "FETCH $id BODY[]";
} else {
$query = "FETCH $id BODY[$ent_id]";
}
sqimap_run_command($imap_stream,$query,true,$response,$message,$uid_support,'sqimap_base64_decode',$rStream,true);
} else {
$body = mime_fetch_body ($imap_stream, $id, $ent_id);
if ($rStream !== 'php://stdout') {
fwrite($rStream, decodeBody($body, $encoding));
} else {
echo decodeBody($body, $encoding);
}
}
return;
}
/* -[ END MIME DECODING ]----------------------------------------------------------- */
/* This is here for debugging purposes. It will print out a list
* of all the entity IDs that are in the $message object.
*/
function listEntities ($message) {
if ($message) {
echo "<tt>" . $message->entity_id . ' : ' . $message->type0 . '/' . $message->type1 . ' parent = '. $message->parent->entity_id. '<br />';
for ($i = 0; isset($message->entities[$i]); $i++) {
echo "$i : ";
$msg = listEntities($message->entities[$i]);
if ($msg) {
echo "return: ";
return $msg;
}
}
}
}
function getPriorityStr($priority) {
$priority_level = substr($priority,0,1);
switch($priority_level) {
/* Check for a higher then normal priority. */
case '1':
case '2':
$priority_string = _("High");
break;
/* Check for a lower then normal priority. */
case '4':
case '5':
$priority_string = _("Low");
break;
/* Check for a normal priority. */
case '3':
default:
$priority_level = '3';
$priority_string = _("Normal");
break;
}
return $priority_string;
}
/* returns a $message object for a particular entity id */
function getEntity ($message, $ent_id) {
return $message->getEntity($ent_id);
}
/* translateText
* Extracted from strings.php 23/03/2002
*/
function translateText(&$body, $wrap_at, $charset) {
global $where, $what; /* from searching */
global $color; /* color theme */
require_once(SM_PATH . 'functions/url_parser.php');
$body_ary = explode("\n", $body);
for ($i=0; $i < count($body_ary); $i++) {
$line = $body_ary[$i];
if (strlen($line) - 2 >= $wrap_at) {
sqWordWrap($line, $wrap_at, $charset);
}
$line = charset_decode($charset, $line);
$line = str_replace("\t", ' ', $line);
parseUrl ($line);
$quotes = 0;
$pos = 0;
$j = strlen($line);
while ($pos < $j) {
if ($line[$pos] == ' ') {
$pos++;
} else if (strpos($line, '>', $pos) === $pos) {
$pos += 4;
$quotes++;
} else {
break;
}
}
if ($quotes % 2) {
if (!isset($color[13])) {
$color[13] = '#800000';
}
$line = '<font color="' . $color[13] . '">' . $line . '</font>';
} elseif ($quotes) {
if (!isset($color[14])) {
$color[14] = '#FF0000';
}
$line = '<font color="' . $color[14] . '">' . $line . '</font>';
}
$body_ary[$i] = $line;
}
$body = '<pre>' . implode("\n", $body_ary) . '</pre>';
}
/**
* This returns a parsed string called $body. That string can then
* be displayed as the actual message in the HTML. It contains
* everything needed, including HTML Tags, Attachments at the
* bottom, etc.
*/
function formatBody($imap_stream, $message, $color, $wrap_at, $ent_num, $id, $mailbox='INBOX',$clean=false) {
/* This if statement checks for the entity to show as the
* primary message. To add more of them, just put them in the
* order that is their priority.
*/
global $startMessage, $languages, $squirrelmail_language,
$show_html_default, $sort, $has_unsafe_images, $passed_ent_id,
$username, $key, $imapServerAddress, $imapPort,
$download_and_unsafe_link;
// If there's no "view_unsafe_images" variable in the URL, turn unsafe
// images off by default.
if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
$view_unsafe_images = false;
}
$body = '';
$urlmailbox = urlencode($mailbox);
$body_message = getEntity($message, $ent_num);
if (($body_message->header->type0 == 'text') ||
($body_message->header->type0 == 'rfc822')) {
$body = mime_fetch_body ($imap_stream, $id, $ent_num);
$body = decodeBody($body, $body_message->header->encoding);
if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
if (mb_detect_encoding($body) != 'ASCII') {
$body = $languages[$squirrelmail_language]['XTRA_CODE']('decode', $body);
}
}
$hookResults = do_hook("message_body", $body);
$body = $hookResults[1];
/* If there are other types that shouldn't be formatted, add
* them here.
*/
if ($body_message->header->type1 == 'html') {
if ($show_html_default <> 1) {
$entity_conv = array(' ' => ' ',
'<p>' => "\n",
'<P>' => "\n",
'<br>' => "\n",
'<BR>' => "\n",
'<br />' => "\n",
'<BR />' => "\n",
'>' => '>',
'<' => '<');
$body = strtr($body, $entity_conv);
$body = strip_tags($body);
$body = trim($body);
translateText($body, $wrap_at,
$body_message->header->getParameter('charset'));
} else {
$charset = $body_message->header->getParameter('charset');
if (!empty($charset))
$body = charset_decode($charset,$body,false,true);
$body = magicHTML($body, $id, $message, $mailbox);
}
} else {
translateText($body, $wrap_at,
$body_message->header->getParameter('charset'));
}
// if this is the clean display (i.e. printer friendly), stop here.
if ( $clean ) {
return $body;
}
/*
* Previously the links for downloading and unsafe images were printed
* under the mail. By putting the links in a global variable we can
* print it in the toolbar where it belongs. Since the original code was
* in this place it's left here. It might be possible to move it to some
* other place if that makes sense. The possibility to do so has not
* been evaluated yet.
*/
// Initialize the global variable to an empty string.
$download_and_unsafe_link = '';
// Prepare and build a link for downloading the mail.
$link = 'passed_id=' . $id . '&ent_id='.$ent_num.
'&mailbox=' . $urlmailbox .'&sort=' . $sort .
'&startMessage=' . $startMessage . '&show_more=0';
if (isset($passed_ent_id)) {
$link .= '&passed_ent_id='.$passed_ent_id;
}
// Always add the link for downloading the mail as a file to the global
// variable.
$download_and_unsafe_link .= ' | <a href="download.php?absolute_dl=true&' .
$link . '" style="white-space: nowrap;">' . _("Download this as a file") . '</a>';
// Find out the right text to use in the link depending on the
// circumstances. If the unsafe images are displayed the link should
// hide them, if they aren't displayed the link should only appear if
// the mail really contains unsafe images.
if ($view_unsafe_images) {
$text = _("Hide Unsafe Images");
} else {
if (isset($has_unsafe_images) && $has_unsafe_images) {
$link .= '&view_unsafe_images=1';
$text = _("View Unsafe Images");
} else {
$text = '';
}
}
// Only create a link for unsafe images if there's need for one. If so:
// add it to the global variable.
if($text != '') {
$download_and_unsafe_link .= ' | <a href="read_body.php?' . $link . '" style="white-space: nowrap;">' . $text . '</a>';
}
}
return $body;
}
function formatAttachments($message, $exclude_id, $mailbox, $id) {
global $where, $what, $startMessage, $color, $passed_ent_id, $block_svg_download;
static $ShownHTML = 0;
$att_ar = $message->getAttachments($exclude_id);
if (!count($att_ar)) return '';
$attachments = '';
$urlMailbox = urlencode($mailbox);
foreach ($att_ar as $att) {
$ent = $att->entity_id;
$header = $att->header;
$type0 = strtolower($header->type0);
$type1 = strtolower($header->type1);
if ($block_svg_download && strpos($type1, 'svg') === 0)
continue;
$name = '';
$links['download link']['text'] = _("Download");
$links['download link']['href'] = SM_PATH .
"src/download.php?absolute_dl=true&passed_id=$id&mailbox=$urlMailbox&ent_id=$ent";
$ImageURL = '';
if ($type0 =='message' && $type1 == 'rfc822') {
$default_page = SM_PATH . 'src/read_body.php';
$rfc822_header = $att->rfc822_header;
$filename = $rfc822_header->subject;
if (trim( $filename ) == '') {
$filename = 'untitled-[' . $ent . ']' ;
}
$from_o = $rfc822_header->from;
if (is_object($from_o)) {
$from_name = $from_o->getAddress(false);
} elseif (is_array($from_o) && count($from_o) && is_object($from_o[0])) {
// when a digest message is opened and you return to the digest
// now the from object is part of an array. This is a workaround.
$from_name = $from_o[0]->getAddress(false);
} else {
$from_name = _("Unknown sender");
}
$from_name = decodeHeader(($from_name));
$description = $from_name;
} else {
$default_page = SM_PATH . 'src/download.php';
if (is_object($header->disposition)) {
$filename = $header->disposition->getProperty('filename');
if (trim($filename) == '') {
$name = decodeHeader($header->disposition->getProperty('name'));
if (trim($name) == '') {
$name = $header->getParameter('name');
if(trim($name) == '') {
if (trim( $header->id ) == '') {
$filename = 'untitled-[' . $ent . ']' . '.' . strtolower($header->type1);
} else {
$filename = 'cid: ' . $header->id . '.' . strtolower($header->type1);
}
} else {
$filename = $name;
}
} else {
$filename = $name;
}
}
} else {
$filename = $header->getParameter('name');
if (!trim($filename)) {
if (trim( $header->id ) == '') {
$filename = 'untitled-[' . $ent . ']' . '.' . strtolower($header->type1) ;
} else {
$filename = 'cid: ' . $header->id . '.' . strtolower($header->type1);
}
}
}
if ($header->description) {
$description = decodeHeader($header->description);
} else {
$description = '';
}
}
$display_filename = $filename;
if (isset($passed_ent_id)) {
$passed_ent_id_link = '&passed_ent_id='.$passed_ent_id;
} else {
$passed_ent_id_link = '';
}
$defaultlink = $default_page . "?startMessage=$startMessage"
. "&passed_id=$id&mailbox=$urlMailbox"
. '&ent_id='.$ent.$passed_ent_id_link;
if ($where && $what) {
$defaultlink .= '&where='. urlencode($where).'&what='.urlencode($what);
}
// IE does make use of mime content sniffing. Forcing a download
// prohibit execution of XSS inside an application/octet-stream attachment
if ($type0 == 'application' && $type1 == 'octet-stream') {
$defaultlink .= '&absolute_dl=true';
}
/* This executes the attachment hook with a specific MIME-type.
* If that doesn't have results, it tries if there's a rule
* for a more generic type. Finally, a hook for ALL attachment
* types is run as well.
*/
$hookresults = do_hook("attachment $type0/$type1", $links,
$startMessage, $id, $urlMailbox, $ent, $defaultlink,
$display_filename, $where, $what);
$hookresults = do_hook("attachment $type0/*", $hookresults[1],
$startMessage, $id, $urlMailbox, $ent, $hookresults[6],
$display_filename, $where, $what);
$hookresults = do_hook("attachment */*", $hookresults[1],
$startMessage, $id, $urlMailbox, $ent, $hookresults[6],
$display_filename, $where, $what);
$links = $hookresults[1];
$defaultlink = $hookresults[6];
$attachments .= '<tr><td>' .
'<a href="'.$defaultlink.'">'.decodeHeader($display_filename).'</a> </td>' .
'<td><small><b>' . show_readable_size($header->size) .
'</b>  </small></td>' .
'<td><small>[ '.sm_encode_html_special_chars($type0).'/'.sm_encode_html_special_chars($type1).' ] </small></td>' .
'<td><small>';
$attachments .= '<b>' . $description . '</b>';
$attachments .= '</small></td><td><small> ';
$skipspaces = 1;
foreach ($links as $val) {
if ($skipspaces) {
$skipspaces = 0;
} else {
$attachments .= '  |  ';
}
$attachments .= '<a href="' . $val['href'] . '">' . $val['text'] . '</a>';
}
unset($links);
$attachments .= "</td></tr>\n";
}
return $attachments;
}
function sqimap_base64_decode(&$string) {
// Base64 encoded data goes in pairs of 4 bytes. To achieve on the
// fly decoding (to reduce memory usage) you have to check if the
// data has incomplete pairs
// Remove the noise in order to check if the 4 bytes pairs are complete
$string = str_replace(array("\r\n","\n", "\r", " "),array('','','',''),$string);
$sStringRem = '';
$iMod = strlen($string) % 4;
if ($iMod) {
$sStringRem = substr($string,-$iMod);
// Check if $sStringRem contains padding characters
if (substr($sStringRem,-1) != '=') {
$string = substr($string,0,-$iMod);
} else {
$sStringRem = '';
}
}
$string = base64_decode($string);
return $sStringRem;
}
/**
* Decodes encoded message body
*
* This function decodes the body depending on the encoding type.
* Currently quoted-printable and base64 encodings are supported.
* decode_body hook was added to this function in 1.4.2/1.5.0
* @param string $body encoded message body
* @param string $encoding used encoding
* @return string decoded string
* @since 1.0
*/
function decodeBody($body, $encoding) {
$body = str_replace("\r\n", "\n", $body);
$encoding = strtolower($encoding);
$encoding_handler = do_hook_function('decode_body', $encoding);
// plugins get first shot at decoding the body
if (!empty($encoding_handler) && function_exists($encoding_handler)) {
$body = $encoding_handler('decode', $body);
} elseif ($encoding == 'quoted-printable' ||
$encoding == 'quoted_printable') {
/**
* quoted_printable_decode() function is broken in older
* php versions. Text with \r\n decoding was fixed only
* in php 4.3.0. Minimal code requirement 4.0.4 +
* str_replace("\r\n", "\n", $body); call.
*/
$body = quoted_printable_decode($body);
} elseif ($encoding == 'base64') {
$body = base64_decode($body);
}
// All other encodings are returned raw.
return $body;
}
/**
* Decodes headers
*
* This functions decode strings that is encoded according to
* RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
* Patched by Christian Schmidt <[email protected]> 23/03/2002
*/
function decodeHeader ($string, $utfencode=true,$htmlsave=true,$decide=false) {
global $languages, $squirrelmail_language,$default_charset, $fix_broken_base64_encoded_messages;
if (is_array($string)) {
$string = implode("\n", $string);
}
if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
$string = $languages[$squirrelmail_language]['XTRA_CODE']('decodeheader', $string);
// Do we need to return at this point?
// return $string;
}
$i = 0;
$iLastMatch = -2;
$encoded = false;
// FIXME: spaces are allowed inside quoted-printable encoding, but the following line will bust up any such encoded strings
$aString = explode(' ',$string);
$ret = '';
foreach ($aString as $chunk) {
if ($encoded && $chunk === '') {
continue;
} elseif ($chunk === '') {
$ret .= ' ';
continue;
}
$encoded = false;
/* if encoded words are not separated by a linear-space-white we still catch them */
$j = $i-1;
while ($match = preg_match('/^(.*)=\?([^?]*)\?(Q|B)\?([^?]*)\?=(.*)$/Ui',$chunk,$res)) {
/* if the last chunk isn't an encoded string then put back the space, otherwise don't */
if ($iLastMatch !== $j) {
if ($htmlsave) {
$ret .= ' ';
} else {
$ret .= ' ';
}
}
$iLastMatch = $i;
$j = $i;
if ($htmlsave) {
$ret .= sm_encode_html_special_chars($res[1]);
} else {
$ret .= $res[1];
}
$encoding = ucfirst($res[3]);
/* decide about valid decoding */
if ($decide && is_conversion_safe($res[2])) {
$can_be_encoded=true;
} else {
$can_be_encoded=false;
}
switch ($encoding)
{
case 'B':
// fix broken base64-encoded strings (remove end = padding,
// change any = to + in middle of string, add padding back
// to the end)
if ($fix_broken_base64_encoded_messages) {
$encoded_string_minus_padding = strtr(rtrim($res[4], '='), '=', '+');
$res[4] = str_pad($encoded_string_minus_padding, strlen($res[4]), '=');
}
$replace = base64_decode($res[4]);
if ($can_be_encoded) {
// string is converted from one charset to another. sanitizing depends on $htmlsave
$replace = charset_convert($res[2],$replace,$default_charset,$htmlsave);
} elseif ($utfencode) {
// string is converted to htmlentities and sanitized
$replace = charset_decode($res[2],$replace);
} elseif ($htmlsave) {
// string is not converted, but still sanitized
$replace = sm_encode_html_special_chars($replace);
}
$ret.= $replace;
break;
case 'Q':
$replace = str_replace('_', ' ', $res[4]);
$replace = preg_replace_callback('/=([0-9a-f]{2})/i',
create_function ('$matches', 'return chr(hexdec($matches[1]));'),
$replace);
if ($can_be_encoded) {
// string is converted from one charset to another. sanitizing depends on $htmlsave
$replace = charset_convert($res[2], $replace,$default_charset,$htmlsave);
} elseif ($utfencode) {
// string is converted to html entities and sanitized
$replace = charset_decode($res[2], $replace);
} elseif ($htmlsave) {
// string is not converted, but still sanizited
$replace = sm_encode_html_special_chars($replace);
}
$ret .= $replace;
break;
default:
break;
}
$chunk = $res[5];
$encoded = true;
}
if (!$encoded) {
if ($htmlsave) {
$ret .= ' ';
} else {
$ret .= ' ';
}
}
if (!$encoded && $htmlsave) {
$ret .= sm_encode_html_special_chars($chunk);
} else {
$ret .= $chunk;
}
++$i;
}
/* remove the first added space */
if ($ret) {
if ($htmlsave) {
$ret = substr($ret,5);
} else {
$ret = substr($ret,1);
}
}
return $ret;
}
/**
* Encodes header as quoted-printable
*
* Encode a string according to RFC 1522 for use in headers if it
* contains 8-bit characters or anything that looks like it should
* be encoded.
*/
function encodeHeader ($string) {
global $default_charset, $languages, $squirrelmail_language;
if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
return $languages[$squirrelmail_language]['XTRA_CODE']('encodeheader', $string);
}
// Use B encoding for multibyte charsets
$mb_charsets = array('utf-8','big5','gb2313','euc-kr');
if (in_array($default_charset,$mb_charsets) &&
in_array($default_charset,sq_mb_list_encodings()) &&
sq_is8bit($string)) {
return encodeHeaderBase64($string,$default_charset);
} elseif (in_array($default_charset,$mb_charsets) &&
sq_is8bit($string) &&
! in_array($default_charset,sq_mb_list_encodings())) {
// Add E_USER_NOTICE error here (can cause 'Cannot add header information' warning in compose.php)
// trigger_error('encodeHeader: Multibyte character set unsupported by mbstring extension.',E_USER_NOTICE);
}
// Encode only if the string contains 8-bit characters or =?
$j = strlen($string);
$max_l = 75 - strlen($default_charset) - 7;
$aRet = array();
$ret = '';
$iEncStart = $enc_init = false;
$cur_l = $iOffset = 0;
for($i = 0; $i < $j; ++$i) {
switch($string{$i})
{
case '"':
case '=':
case '<':
case '>':
case ',':
case '?':
case '_':
if ($iEncStart === false) {
$iEncStart = $i;
}
$cur_l+=3;
if ($cur_l > ($max_l-2)) {
/* if there is an stringpart that doesn't need encoding, add it */
$aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
$aRet[] = "=?$default_charset?Q?$ret?=";
$iOffset = $i;
$cur_l = 0;
$ret = '';
$iEncStart = false;
} else {
$ret .= sprintf("=%02X",ord($string{$i}));
}
break;
case '(':
case ')':
if ($iEncStart !== false) {
$aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
$aRet[] = "=?$default_charset?Q?$ret?=";
$iOffset = $i;
$cur_l = 0;
$ret = '';
$iEncStart = false;
}
break;
case ' ':
if ($iEncStart !== false) {
$cur_l++;
if ($cur_l > $max_l) {
$aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
$aRet[] = "=?$default_charset?Q?$ret?=";
$iOffset = $i;
$cur_l = 0;
$ret = '';
$iEncStart = false;
} else {
$ret .= '_';
}
}
break;
default:
$k = ord($string{$i});
if ($k > 126) {
if ($iEncStart === false) {
// do not start encoding in the middle of a string, also take the rest of the word.
$sLeadString = substr($string,0,$i);
$aLeadString = explode(' ',$sLeadString);
$sToBeEncoded = array_pop($aLeadString);
$iEncStart = $i - strlen($sToBeEncoded);
$ret .= $sToBeEncoded;
$cur_l += strlen($sToBeEncoded);
}
$cur_l += 3;
/* first we add the encoded string that reached it's max size */
if ($cur_l > ($max_l-2)) {
$aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
$aRet[] = "=?$default_charset?Q?$ret?= "; /* the next part is also encoded => separate by space */
$cur_l = 3;
$ret = '';
$iOffset = $i;
$iEncStart = $i;
}
$enc_init = true;
$ret .= sprintf("=%02X", $k);
} else {
if ($iEncStart !== false) {
$cur_l++;
if ($cur_l > $max_l) {
$aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
$aRet[] = "=?$default_charset?Q?$ret?=";
$iEncStart = false;
$iOffset = $i;
$cur_l = 0;
$ret = '';
} else {
$ret .= $string{$i};
}
}
}
break;
}
}
if ($enc_init) {
if ($iEncStart !== false) {
$aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
$aRet[] = "=?$default_charset?Q?$ret?=";
} else {
$aRet[] = substr($string,$iOffset);
}
$string = implode('',$aRet);
}
return $string;
}
/**
* Encodes string according to rfc2047 B encoding header formating rules
*
* It is recommended way to encode headers with character sets that store
* symbols in more than one byte.
*
* Function requires mbstring support. If required mbstring functions are missing,
* function returns false and sets E_USER_WARNING level error message.
*
* Minimal requirements - php 4.0.6 with mbstring extension. Please note,
* that mbstring functions will generate E_WARNING errors, if unsupported
* character set is used. mb_encode_mimeheader function provided by php
* mbstring extension is not used in order to get better control of header
* encoding.
*
* Used php code functions - function_exists(), trigger_error(), strlen()
* (is used with charset names and base64 strings). Used php mbstring
* functions - mb_strlen and mb_substr.
*
* Related documents: rfc 2045 (BASE64 encoding), rfc 2047 (mime header
* encoding), rfc 2822 (header folding)
*
* @param string $string header string that must be encoded
* @param string $charset character set. Must be supported by mbstring extension.
* Use sq_mb_list_encodings() to detect supported charsets.
* @return string string encoded according to rfc2047 B encoding formating rules
* @since 1.5.1 and 1.4.6
*/
function encodeHeaderBase64($string,$charset) {
/**
* Check mbstring function requirements.
*/
if (! function_exists('mb_strlen') ||
! function_exists('mb_substr')) {
// set E_USER_WARNING
trigger_error('encodeHeaderBase64: Required mbstring functions are missing.',E_USER_WARNING);
// return false
return false;
}
// initial return array
$aRet = array();
/**
* header length = 75 symbols max (same as in encodeHeader)
* remove $charset length
* remove =? ? ?= (5 chars)
* remove 2 more chars (\r\n ?)
*/
$iMaxLength = 75 - strlen($charset) - 7;
// set first character position
$iStartCharNum = 0;
// loop through all characters. count characters and not bytes.
for ($iCharNum=1; $iCharNum<=mb_strlen($string,$charset); $iCharNum++) {
// encode string from starting character to current character.
$encoded_string = base64_encode(mb_substr($string,$iStartCharNum,$iCharNum-$iStartCharNum,$charset));
// Check encoded string length
if(strlen($encoded_string)>$iMaxLength) {
// if string exceeds max length, reduce number of encoded characters and add encoded string part to array
$aRet[] = base64_encode(mb_substr($string,$iStartCharNum,$iCharNum-$iStartCharNum-1,$charset));
// set new starting character
$iStartCharNum = $iCharNum-1;
// encode last char (in case it is last character in string)
$encoded_string = base64_encode(mb_substr($string,$iStartCharNum,$iCharNum-$iStartCharNum,$charset));
} // if string is shorter than max length - add next character
}
// add last encoded string to array
$aRet[] = $encoded_string;
// set initial return string
$sRet = '';
// loop through encoded strings
foreach($aRet as $string) {
// TODO: Do we want to control EOL (end-of-line) marker
if ($sRet!='') $sRet.= " ";
// add header tags and encoded string to return string
$sRet.= '=?'.$charset.'?B?'.$string.'?=';
}
return $sRet;
}
/* This function trys to locate the entity_id of a specific mime element */
function find_ent_id($id, $message) {
for ($i = 0, $ret = ''; $ret == '' && $i < count($message->entities); $i++) {
if ($message->entities[$i]->header->type0 == 'multipart') {
$ret = find_ent_id($id, $message->entities[$i]);
} else {
if (strcasecmp($message->entities[$i]->header->id, $id) == 0) {
// if (sq_check_save_extension($message->entities[$i])) {
return $message->entities[$i]->entity_id;
// }
} elseif (!empty($message->entities[$i]->header->parameters['name'])) {
/**
* This is part of a fix for Outlook Express 6.x generating
* cid URLs without creating content-id headers
* @@JA - 20050207
*/
if (strcasecmp($message->entities[$i]->header->parameters['name'], $id) == 0) {
return $message->entities[$i]->entity_id;
}
}
}
}
return $ret;
}
function sq_check_save_extension($message) {
$filename = $message->getFilename();
$ext = substr($filename, strrpos($filename,'.')+1);
$save_extensions = array('jpg','jpeg','gif','png','bmp');
return in_array($ext, $save_extensions);
}
/**
** HTMLFILTER ROUTINES
*/
/**
* This function checks attribute values for entity-encoded values
* and returns them translated into 8-bit strings so we can run
* checks on them.
*
* @param $attvalue A string to run entity check against.
* @return Nothing, modifies a reference value.
*/
function sq_defang(&$attvalue){
$me = 'sq_defang';
/**
* Skip this if there aren't ampersands or backslashes.
*/
if (strpos($attvalue, '&') === false
&& strpos($attvalue, '\\') === false){
return;
}
$m = false;
do {
$m = false;
$m = $m || sq_deent($attvalue, '/\&#0*(\d+);*/s');
$m = $m || sq_deent($attvalue, '/\&#x0*((\d|[a-f])+);*/si', true);
$m = $m || sq_deent($attvalue, '/\\\\(\d+)/s', true);
} while ($m == true);
$attvalue = stripslashes($attvalue);
}
/**
* Kill any tabs, newlines, or carriage returns. Our friends the
* makers of the browser with 95% market value decided that it'd
* be funny to make "java[tab]script" be just as good as "javascript".
*
* @param attvalue The attribute value before extraneous spaces removed.
* @return attvalue Nothing, modifies a reference value.
*/
function sq_unspace(&$attvalue){
$me = 'sq_unspace';
if (strcspn($attvalue, "\t\r\n\0 ") != strlen($attvalue)){
$attvalue = str_replace(Array("\t", "\r", "\n", "\0", " "),
Array('', '', '', '', ''), $attvalue);
}
}
/**
* Translate all dangerous Unicode or Shift_JIS characters which are accepted by
* IE as regular characters.
*
* @param attvalue The attribute value before dangerous characters are translated.
* @return attvalue Nothing, modifies a reference value.
* @author Marc Groot Koerkamp.
*/
function sq_fixIE_idiocy(&$attvalue) {
// remove NUL
$attvalue = str_replace("\0", "", $attvalue);
// remove comments
$attvalue = preg_replace("/(\/\*.*?\*\/)/","",$attvalue);
// IE has the evil habit of accepting every possible value for the attribute expression.
// The table below contains characters which are parsed by IE if they are used in the "expression"
// attribute value.
$aDangerousCharsReplacementTable = array(
array('ʟ', 'ʟ' ,/* L UNICODE IPA Extension */
'ʀ', 'ʀ' ,/* R UNICODE IPA Extension */
'ɴ', 'ɴ' ,/* N UNICODE IPA Extension */
'Ｅ', 'Ｅ' ,/* Unicode FULLWIDTH LATIN CAPITAL LETTER E */
'ｅ', 'ｅ' ,/* Unicode FULLWIDTH LATIN SMALL LETTER E */
'Ｘ', 'Ｘ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER X */
'ｘ', 'ｘ',/* Unicode FULLWIDTH LATIN SMALL LETTER X */
'Ｐ', 'Ｐ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER P */
'ｐ', 'ｐ',/* Unicode FULLWIDTH LATIN SMALL LETTER P */
'Ｒ', 'Ｒ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER R */
'ｒ', 'ｒ',/* Unicode FULLWIDTH LATIN SMALL LETTER R */
'Ｓ', 'Ｓ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER S */
'ｓ', 'ｓ',/* Unicode FULLWIDTH LATIN SMALL LETTER S */
'Ｉ', 'Ｉ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER I */
'ｉ', 'ｉ',/* Unicode FULLWIDTH LATIN SMALL LETTER I */
'Ｏ', 'Ｏ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER O */
'ｏ', 'ｏ',/* Unicode FULLWIDTH LATIN SMALL LETTER O */
'Ｎ', 'Ｎ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER N */
'ｎ', 'ｎ',/* Unicode FULLWIDTH LATIN SMALL LETTER N */
'Ｌ', 'Ｌ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER L */
'ｌ', 'ｌ',/* Unicode FULLWIDTH LATIN SMALL LETTER L */
'Ｕ', 'Ｕ',/* Unicode FULLWIDTH LATIN CAPITAL LETTER U */
'ｕ', 'ｕ',/* Unicode FULLWIDTH LATIN SMALL LETTER U */
'ⁿ', 'ⁿ' ,/* Unicode SUPERSCRIPT LATIN SMALL LETTER N */
"\xEF\xBC\xA5", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER E */ // in unicode this is some Chinese char range
"\xEF\xBD\x85", /* Shift JIS FULLWIDTH LATIN SMALL LETTER E */
"\xEF\xBC\xB8", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER X */
"\xEF\xBD\x98", /* Shift JIS FULLWIDTH LATIN SMALL LETTER X */
"\xEF\xBC\xB0", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER P */
"\xEF\xBD\x90", /* Shift JIS FULLWIDTH LATIN SMALL LETTER P */
"\xEF\xBC\xB2", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER R */
"\xEF\xBD\x92", /* Shift JIS FULLWIDTH LATIN SMALL LETTER R */
"\xEF\xBC\xB3", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER S */
"\xEF\xBD\x93", /* Shift JIS FULLWIDTH LATIN SMALL LETTER S */
"\xEF\xBC\xA9", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER I */
"\xEF\xBD\x89", /* Shift JIS FULLWIDTH LATIN SMALL LETTER I */
"\xEF\xBC\xAF", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER O */
"\xEF\xBD\x8F", /* Shift JIS FULLWIDTH LATIN SMALL LETTER O */
"\xEF\xBC\xAE", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER N */
"\xEF\xBD\x8E", /* Shift JIS FULLWIDTH LATIN SMALL LETTER N */
"\xEF\xBC\xAC", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER L */
"\xEF\xBD\x8C", /* Shift JIS FULLWIDTH LATIN SMALL LETTER L */
"\xEF\xBC\xB5", /* Shift JIS FULLWIDTH LATIN CAPITAL LETTER U */
"\xEF\xBD\x95", /* Shift JIS FULLWIDTH LATIN SMALL LETTER U */
"\xE2\x81\xBF", /* Shift JIS FULLWIDTH SUPERSCRIPT N */
"\xCA\x9F", /* L UNICODE IPA Extension */
"\xCA\x80", /* R UNICODE IPA Extension */
"\xC9\xB4"), /* N UNICODE IPA Extension */
array('l', 'l', 'r','r','n','n',
'E','E','e','e','X','X','x','x','P','P','p','p','R','R','r','r','S','S','s','s','I','I',
'i','i','O','O','o','o','N','N','n','n','L','L','l','l','U','U','u','u','n','n',
'E','e','X','x','P','p','R','r','S','s','I','i','O','o','N','n','L','l','U','u','n','l','r','n'));
$attvalue = str_replace($aDangerousCharsReplacementTable[0],$aDangerousCharsReplacementTable[1],$attvalue);
// Escapes are useful for special characters like "{}[]()'&. In other cases they are
// used for XSS.
$attvalue = preg_replace("/(\\\\)([a-zA-Z]{1})/",'$2',$attvalue);
}
/**
* This function returns the final tag out of the tag name, an array
* of attributes, and the type of the tag. This function is called by
* sq_sanitize internally.
*
* @param $tagname the name of the tag.
* @param $attary the array of attributes and their values
* @param $tagtype The type of the tag (see in comments).
* @return a string with the final tag representation.
*/
function sq_tagprint($tagname, $attary, $tagtype){
$me = 'sq_tagprint';
if ($tagtype == 2){
$fulltag = '</' . $tagname . '>';
} else {
$fulltag = '<' . $tagname;
if (is_array($attary) && sizeof($attary)){
$atts = Array();
while (list($attname, $attvalue) = each($attary)){
array_push($atts, "$attname=$attvalue");
}
$fulltag .= ' ' . join(" ", $atts);
}
if ($tagtype == 3){
$fulltag .= ' /';
}
$fulltag .= '>';
}
return $fulltag;
}
/**
* A small helper function to use with array_walk. Modifies a by-ref
* value and makes it lowercase.
*
* @param $val a value passed by-ref.
* @return void since it modifies a by-ref value.
*/
function sq_casenormalize(&$val){
$val = strtolower($val);
}
/**
* This function skips any whitespace from the current position within
* a string and to the next non-whitespace value.
*
* @param $body the string
* @param $offset the offset within the string where we should start
* looking for the next non-whitespace character.
* @return the location within the $body where the next
* non-whitespace char is located.
*/
function sq_skipspace($body, $offset){
$me = 'sq_skipspace';
preg_match('/^(\s*)/s', substr($body, $offset), $matches);
if (!empty($matches[1])){
$offset += strlen($matches[1]);
}
return $offset;
}
/**
* This function looks for the next character within a string. It's
* really just a glorified "strpos", except it catches if failures
* nicely.
*
* @param $body The string to look for needle in.
* @param $offset Start looking from this position.
* @param $needle The character/string to look for.
* @return location of the next occurance of the needle, or
* strlen($body) if needle wasn't found.
*/
function sq_findnxstr($body, $offset, $needle){
$me = 'sq_findnxstr';
$pos = strpos($body, $needle, $offset);
if ($pos === FALSE){
$pos = strlen($body);
}
return $pos;
}
/**
* This function takes a PCRE-style regexp and tries to match it
* within the string.
*
* @param $body The string to look for needle in.
* @param $offset Start looking from here.
* @param $reg A PCRE-style regex to match.
* @return Returns a false if no matches found, or an array
* with the following members:
* - integer with the location of the match within $body
* - string with whatever content between offset and the match
* - string with whatever it is we matched
*/
function sq_findnxreg($body, $offset, $reg){
$me = 'sq_findnxreg';
$matches = Array();
$retarr = Array();
preg_match("%^(.*?)($reg)%si", substr($body, $offset), $matches);
if (!isset($matches{0}) || !$matches{0}){
$retarr = false;
} else {
$retarr{0} = $offset + strlen($matches{1});
$retarr{1} = $matches{1};
$retarr{2} = $matches{2};
}
return $retarr;
}
/**
* This function looks for the next tag.
*
* @param $body String where to look for the next tag.
* @param $offset Start looking from here.
* @return false if no more tags exist in the body, or
* an array with the following members:
* - string with the name of the tag
* - array with attributes and their values
* - integer with tag type (1, 2, or 3)
* - integer where the tag starts (starting "<")
* - integer where the tag ends (ending ">")
* first three members will be false, if the tag is invalid.
*/
function sq_getnxtag($body, $offset){
$me = 'sq_getnxtag';
if ($offset > strlen($body)){
return false;
}
$lt = sq_findnxstr($body, $offset, "<");
if ($lt == strlen($body)){
return false;
}
/**
* We are here:
* blah blah <tag attribute="value">
* \---------^
*/
$pos = sq_skipspace($body, $lt+1);
if ($pos >= strlen($body)){
return Array(false, false, false, $lt, strlen($body));
}
/**
* There are 3 kinds of tags:
* 1. Opening tag, e.g.:
* <a href="blah">
* 2. Closing tag, e.g.:
* </a>
* 3. XHTML-style content-less tag, e.g.:
* <img src="blah" />
*/
$tagtype = false;
switch (substr($body, $pos, 1)){
case '/':
$tagtype = 2;
$pos++;
break;
case '!':
/**
* A comment or an SGML declaration.
*/
if (substr($body, $pos+1, 2) == "--"){
$gt = strpos($body, "-->", $pos);
if ($gt === false){
$gt = strlen($body);
} else {
$gt += 2;
}
return Array(false, false, false, $lt, $gt);
} else {
$gt = sq_findnxstr($body, $pos, ">");
return Array(false, false, false, $lt, $gt);
}
break;
default:
/**
* Assume tagtype 1 for now. If it's type 3, we'll switch values
* later.
*/
$tagtype = 1;
break;
}
$tag_start = $pos;
$tagname = '';
/**
* Look for next [\W-_], which will indicate the end of the tag name.
*/
$regary = sq_findnxreg($body, $pos, "[^\w\-_]");
if ($regary == false){
return Array(false, false, false, $lt, strlen($body));
}
list($pos, $tagname, $match) = $regary;
$tagname = strtolower($tagname);
/**
* $match can be either of these:
* '>' indicating the end of the tag entirely.
* '\s' indicating the end of the tag name.
* '/' indicating that this is type-3 xhtml tag.
*
* Whatever else we find there indicates an invalid tag.
*/
switch ($match){
case '/':
/**
* This is an xhtml-style tag with a closing / at the
* end, like so: <img src="blah" />. Check if it's followed
* by the closing bracket. If not, then this tag is invalid
*/
if (substr($body, $pos, 2) == "/>"){
$pos++;
$tagtype = 3;
} else {
$gt = sq_findnxstr($body, $pos, ">");
$retary = Array(false, false, false, $lt, $gt);
return $retary;
}
case '>':
return Array($tagname, false, $tagtype, $lt, $pos);
break;
default:
/**
* Check if it's whitespace
*/
if (!preg_match('/\s/', $match)){
/**
* This is an invalid tag! Look for the next closing ">".
*/
$gt = sq_findnxstr($body, $lt, ">");
return Array(false, false, false, $lt, $gt);
}
break;
}
/**
* At this point we're here:
* <tagname attribute='blah'>
* \-------^
*
* At this point we loop in order to find all attributes.
*/
$attname = '';
$atttype = false;
$attary = Array();
while ($pos <= strlen($body)){
$pos = sq_skipspace($body, $pos);
if ($pos == strlen($body)){
/**
* Non-closed tag.
*/
return Array(false, false, false, $lt, $pos);
}
/**
* See if we arrived at a ">" or "/>", which means that we reached
* the end of the tag.
*/
$matches = Array();
if (preg_match("%^(\s*)(>|/>)%s", substr($body, $pos), $matches)) {
/**
* Yep. So we did.
*/
$pos += strlen($matches{1});
if ($matches{2} == "/>"){
$tagtype = 3;
$pos++;
}
return Array($tagname, $attary, $tagtype, $lt, $pos);
}
/**
* There are several types of attributes, with optional
* [:space:] between members.
* Type 1:
* attrname[:space:]=[:space:]'CDATA'
* Type 2:
* attrname[:space:]=[:space:]"CDATA"
* Type 3:
* attr[:space:]=[:space:]CDATA
* Type 4:
* attrname
*
* We leave types 1 and 2 the same, type 3 we check for
* '"' and convert to "&quot" if needed, then wrap in
* double quotes. Type 4 we convert into:
* attrname="yes".
*/
$regary = sq_findnxreg($body, $pos, "[^:\w\-_]");
if ($regary == false){
/**
* Looks like body ended before the end of tag.
*/
return Array(false, false, false, $lt, strlen($body));
}
list($pos, $attname, $match) = $regary;
$attname = strtolower($attname);
/**
* We arrived at the end of attribute name. Several things possible
* here:
* '>' means the end of the tag and this is attribute type 4
* '/' if followed by '>' means the same thing as above
* '\s' means a lot of things -- look what it's followed by.
* anything else means the attribute is invalid.
*/
switch($match){
case '/':
/**
* This is an xhtml-style tag with a closing / at the
* end, like so: <img src="blah" />. Check if it's followed
* by the closing bracket. If not, then this tag is invalid
*/
if (substr($body, $pos, 2) == "/>"){
$pos++;
$tagtype = 3;
} else {
$gt = sq_findnxstr($body, $pos, ">");
$retary = Array(false, false, false, $lt, $gt);
return $retary;
}
case '>':
$attary{$attname} = '"yes"';
return Array($tagname, $attary, $tagtype, $lt, $pos);
break;
default:
/**
* Skip whitespace and see what we arrive at.
*/
$pos = sq_skipspace($body, $pos);
$char = substr($body, $pos, 1);
/**
* Two things are valid here:
* '=' means this is attribute type 1 2 or 3.
* \w means this was attribute type 4.
* anything else we ignore and re-loop. End of tag and
* invalid stuff will be caught by our checks at the beginning
* of the loop.
*/
if ($char == "="){
$pos++;
$pos = sq_skipspace($body, $pos);
/**
* Here are 3 possibilities:
* "'" attribute type 1
* '"' attribute type 2
* everything else is the content of tag type 3
*/
$quot = substr($body, $pos, 1);
if ($quot == "'"){
$regary = sq_findnxreg($body, $pos+1, "\'");
if ($regary == false){
return Array(false, false, false, $lt, strlen($body));
}
list($pos, $attval, $match) = $regary;
$pos++;
$attary{$attname} = "'" . $attval . "'";
} else if ($quot == '"'){
$regary = sq_findnxreg($body, $pos+1, '\"');
if ($regary == false){
return Array(false, false, false, $lt, strlen($body));
}
list($pos, $attval, $match) = $regary;
$pos++;
$attary{$attname} = '"' . $attval . '"';
} else {
/**
* These are hateful. Look for \s, or >.
*/
$regary = sq_findnxreg($body, $pos, "[\s>]");
if ($regary == false){
return Array(false, false, false, $lt, strlen($body));
}
list($pos, $attval, $match) = $regary;
/**
* If it's ">" it will be caught at the top.
*/
$attval = preg_replace("/\"/s", """, $attval);
$attary{$attname} = '"' . $attval . '"';
}
} else if (preg_match("|[\w/>]|", $char)) {
/**
* That was attribute type 4.
*/
$attary{$attname} = '"yes"';
} else {
/**
* An illegal character. Find next '>' and return.
*/
$gt = sq_findnxstr($body, $pos, ">");
return Array(false, false, false, $lt, $gt);
}
break;
}
}
/**
* The fact that we got here indicates that the tag end was never
* found. Return invalid tag indication so it gets stripped.
*/
return Array(false, false, false, $lt, strlen($body));
}
/**
* Translates entities into literal values so they can be checked.
*
* @param $attvalue the by-ref value to check.
* @param $regex the regular expression to check against.
* @param $hex whether the entites are hexadecimal.
* @return True or False depending on whether there were matches.
*/
function sq_deent(&$attvalue, $regex, $hex=false){
$me = 'sq_deent';
$ret_match = false;
preg_match_all($regex, $attvalue, $matches);
if (is_array($matches) && sizeof($matches[0]) > 0){
$repl = Array();
for ($i = 0; $i < sizeof($matches[0]); $i++){
$numval = $matches[1][$i];
if ($hex){
$numval = hexdec($numval);
}
$repl{$matches[0][$i]} = chr($numval);
}
$attvalue = strtr($attvalue, $repl);
return true;
} else {
return false;
}
}
/**
* This function runs various checks against the attributes.
*
* @param $tagname String with the name of the tag.
* @param $attary Array with all tag attributes.
* @param $rm_attnames See description for sq_sanitize
* @param $bad_attvals See description for sq_sanitize
* @param $add_attr_to_tag See description for sq_sanitize
* @param $message message object
* @param $id message id
* @param $mailbox mailbox
* @return Array with modified attributes.
*/
function sq_fixatts($tagname,
$attary,
$rm_attnames,
$bad_attvals,
$add_attr_to_tag,
$message,
$id,
$mailbox
){
$me = 'sq_fixatts';
while (list($attname, $attvalue) = each($attary)){
/**
* See if this attribute should be removed.
*/
foreach ($rm_attnames as $matchtag=>$matchattrs){
if (preg_match($matchtag, $tagname)){
foreach ($matchattrs as $matchattr){
if (preg_match($matchattr, $attname)){
unset($attary{$attname});
continue;
}
}
}
}
/**
* Workaround for IE quirks
*/
sq_fixIE_idiocy($attvalue);
/**
* Remove any backslashes, entities, and extraneous whitespace.
*/
$oldattvalue = $attvalue;
sq_defang($attvalue);
if ($attname == 'style' && $attvalue !== $oldattvalue) {
// entities are used in the attribute value. In 99% of the cases it's there as XSS
// i.e.<div style="{ left:expʀessioɴ( alert('XSS') ) }">
$attvalue = "idiocy";
$attary{$attname} = $attvalue;
}
sq_unspace($attvalue);
/**
* Now let's run checks on the attvalues.
* I don't expect anyone to comprehend this. If you do,
* get in touch with me so I can drive to where you live and
* shake your hand personally. :)
*/
foreach ($bad_attvals as $matchtag=>$matchattrs){
if (preg_match($matchtag, $tagname)){
foreach ($matchattrs as $matchattr=>$valary){
if (preg_match($matchattr, $attname)){
/**
* There are two arrays in valary.
* First is matches.
* Second one is replacements
*/
list($valmatch, $valrepl) = $valary;
$newvalue =
preg_replace($valmatch, $valrepl, $attvalue);
if ($newvalue != $attvalue){
$attary{$attname} = $newvalue;
$attvalue = $newvalue;
}
}
}
}
}
if ($attname == 'style') {
if (preg_match('/[\0-\37\200-\377]+/',$attvalue)) {
// 8bit and control characters in style attribute values can be used for XSS, remove them
$attary{$attname} = '"disallowed character"';
}
preg_match_all("/url\s*$(.+)$/si",$attvalue,$aMatch);
if (count($aMatch)) {
foreach($aMatch[1] as $sMatch) {
// url value
$urlvalue = $sMatch;
sq_fix_url($attname, $urlvalue, $message, $id, $mailbox,"'");
$attary{$attname} = str_replace($sMatch,$urlvalue,$attvalue);
}
}
}
/**
* Use white list based filtering on attributes which can contain url's
*/
else if ($attname == 'href' || $attname == 'xlink:href' || $attname == 'src'
|| $attname == 'poster' || $attname == 'formaction'
|| $attname == 'background' || $attname == 'action') {
sq_fix_url($attname, $attvalue, $message, $id, $mailbox);
$attary{$attname} = $attvalue;
}
}
/**
* See if we need to append any attributes to this tag.
*/
foreach ($add_attr_to_tag as $matchtag=>$addattary){
if (preg_match($matchtag, $tagname)){
$attary = array_merge($attary, $addattary);
}
}
return $attary;
}
/**
* This function filters url's
*
* @param $attvalue String with attribute value to filter
* @param $message message object
* @param $id message id
* @param $mailbox mailbox
* @param $sQuote quoting characters around url's
*/
function sq_fix_url($attname, &$attvalue, $message, $id, $mailbox,$sQuote = '"') {
$attvalue = trim($attvalue);
if ($attvalue && ($attvalue[0] =='"'|| $attvalue[0] == "'")) {
// remove the double quotes
$sQuote = $attvalue[0];
$attvalue = trim(substr($attvalue,1,-1));
}
// If there's no "view_unsafe_images" variable in the URL, turn unsafe
// images off by default.
if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
$view_unsafe_images = false;
}
global $use_transparent_security_image;
if ($use_transparent_security_image) $secremoveimg = '../images/spacer.png';
else $secremoveimg = '../images/' . _("sec_remove_eng.png");
/**
* Replace empty src tags with the blank image. src is only used
* for frames, images, and image inputs. Doing a replace should
* not affect them working as should be, however it will stop
* IE from being kicked off when src for img tags are not set
*/
if ($attvalue == '') {
$attvalue = '"' . SM_PATH . 'images/blank.png"';
} else {
// first, disallow 8 bit characters and control characters
if (preg_match('/[\0-\37\200-\377]+/',$attvalue)) {
switch ($attname) {
case 'href':
$attvalue = $sQuote . 'http://invalid-stuff-detected.example.com' . $sQuote;
break;
default:
$attvalue = $sQuote . SM_PATH . 'images/blank.png'. $sQuote;
break;
}
} else {
$aUrl = parse_url($attvalue);
if (isset($aUrl['scheme'])) {
switch(strtolower($aUrl['scheme'])) {
case 'mailto':
case 'http':
case 'https':
case 'ftp':
if ($attname != 'href') {
if ($view_unsafe_images == false) {
$attvalue = $sQuote . $secremoveimg . $sQuote;
} else {
if (isset($aUrl['path'])) {
// No one has been able to show that image URIs
// can be exploited, so for now, no restrictions
// are made at all. If this proves to be a problem,
// the commented-out code below can be of help.
// (One consideration is that I see nothing in this
// function that specifically says that we will
// only ever arrive here when inspecting an image
// tag, although that does seem to be the end
// result - e.g., <script src="..."> where malicious
// image URIs are in fact a problem are already
// filtered out elsewhere.
/* ---------------------------------
// validate image extension.
$ext = strtolower(substr($aUrl['path'],strrpos($aUrl['path'],'.')));
if (!in_array($ext,array('.jpeg','.jpg','xjpeg','.gif','.bmp','.jpe','.png','.xbm'))) {
// If URI is to something other than
// a regular image file, get the contents
// and try to see if it is an image.
// Don't use Fileinfo (finfo_file()) because
// we'd need to make the admin configure the
// location of the magic.mime file (FIXME: add finfo_file() support later?)
//
$mime_type = '';
if (function_exists('mime_content_type')
&& ($FILE = @fopen($attvalue, 'rb', FALSE))) {
// fetch file
//
$file_contents = '';
while (!feof($FILE)) {
$file_contents .= fread($FILE, 8192);
}
fclose($FILE);
// store file locally
//
global $attachment_dir, $username;
$hashed_attachment_dir = getHashedDir($username, $attachment_dir);
$localfilename = GenerateRandomString(32, '', 7);
$full_localfilename = "$hashed_attachment_dir/$localfilename";
while (file_exists($full_localfilename)) {
$localfilename = GenerateRandomString(32, '', 7);
$full_localfilename = "$hashed_attachment_dir/$localfilename";
}
$FILE = fopen("$hashed_attachment_dir/$localfilename", 'wb');
fwrite($FILE, $file_contents);
fclose($FILE);
// get mime type and remove file
//
$mime_type = mime_content_type("$hashed_attachment_dir/$localfilename");
unlink("$hashed_attachment_dir/$localfilename");
}
// debug: echo "$attvalue FILE TYPE IS $mime_type<HR>";
if (substr(strtolower($mime_type), 0, 5) != 'image') {
$attvalue = $sQuote . SM_PATH . 'images/blank.png'. $sQuote;
}
}
--------------------------------- */
} else {
$attvalue = $sQuote . SM_PATH . 'images/blank.png'. $sQuote;
}
}
} else {
$attvalue = $sQuote . $attvalue . $sQuote;
}
break;
case 'outbind':
/**
* "Hack" fix for Outlook using propriatary outbind:// protocol in img tags.
* One day MS might actually make it match something useful, for now, falling
* back to using cid2http, so we can grab the blank.png.
*/
$attvalue = $sQuote . sq_cid2http($message, $id, $attvalue, $mailbox) . $sQuote;
break;
case 'cid':
/**
* Turn cid: urls into http-friendly ones.
*/
$attvalue = $sQuote . sq_cid2http($message, $id, $attvalue, $mailbox) . $sQuote;
break;
default:
$attvalue = $sQuote . SM_PATH . 'images/blank.png' . $sQuote;
break;
}
} else {
if (!(isset($aUrl['path']) && $aUrl['path'] == $secremoveimg)) {
// parse_url did not lead to satisfying result
$attvalue = $sQuote . SM_PATH . 'images/blank.png' . $sQuote;
}
}
}
}
}
/**
* This function edits the style definition to make them friendly and
* usable in SquirrelMail.
*
* @param $message the message object
* @param $id the message id
* @param $content a string with whatever is between <style> and </style>
* @param $mailbox the message mailbox
* @return a string with edited content.
*/
function sq_fixstyle($body, $pos, $message, $id, $mailbox){
// FIXME: Is the global "view_unsafe_images" really needed here?
global $view_unsafe_images;
$me = 'sq_fixstyle';
// workaround for </style> in between comments
$iCurrentPos = $pos;
$content = '';
$sToken = '';
$bSucces = false;
$bEndTag = false;
for ($i=$pos,$iCount=strlen($body);$i<$iCount;++$i) {
$char = $body{$i};
switch ($char) {
case '<':
$sToken = $char;
break;
case '/':
if ($sToken == '<') {
$sToken .= $char;
$bEndTag = true;
} else {
$content .= $char;
}
break;
case '>':
if ($bEndTag) {
$sToken .= $char;
if (preg_match('/\<\/\s*style\s*\>/i',$sToken,$aMatch)) {
$newpos = $i + 1;
$bSucces = true;
break 2;
} else {
$content .= $sToken;
}
$bEndTag = false;
} else {
$content .= $char;
}
break;
case '!':
if ($sToken == '<') {
// possible comment
if (isset($body{$i+2}) && substr($body,$i,3) == '!--') {
$i = strpos($body,'-->',$i+3);
if ($i === false) { // no end comment
$i = strlen($body);
}
$sToken = '';
}
} else {
$content .= $char;
}
break;
default:
if ($bEndTag) {
$sToken .= $char;
} else {
$content .= $char;
}
break;
}
}
if ($bSucces == FALSE){
return array(FALSE, strlen($body));
}
/**
* First look for general BODY style declaration, which would be
* like so:
* body {background: blah-blah}
* and change it to .bodyclass so we can just assign it to a <div>
*/
// $content = preg_replace("|body(\s*\{.*?\})|si", ".bodyclass\\1", $content);
// Nah, this is even better - try to preface all CSS selectors with
// our <div> class ID "bodyclass" then correct generic "body" selectors
// TODO: this works pretty good but breaks stuff like this:
// @media print { body { font-size: 10pt; } }
// but there isn't an easy way to make this regex skip @media
// definitions... though lots of the ones in the wild will be
// correctly handled because they tend to end with a parenthesis, like:
// @media screen and (max-width:480px) { ...
$content = preg_replace('/([a-z0-9._-][a-z0-9 >+~|:._-]*\s*(?:,|{.*?}))/si', '.bodyclass $1', $content);
$content = str_replace('.bodyclass body', '.bodyclass', $content);
global $use_transparent_security_image;
if ($use_transparent_security_image) $secremoveimg = '../images/spacer.png';
else $secremoveimg = '../images/' . _("sec_remove_eng.png");
// first check for 8bit sequences and disallowed control characters
if (preg_match('/[\16-\37\200-\377]+/',$content)) {
$content = '';
return array($content, $newpos);
}
// IE Sucks hard. We have a special function for it.
sq_fixIE_idiocy($content);
// remove @import line
$content = preg_replace("/^\s*(@import.*)$/mi","\n\n",$content);
/**
* Fix url('blah') declarations.
*/
// translate ur\l and variations into url (IE parses that)
// TODO check if the sq_fixIE_idiocy function already handles this.
$content = preg_replace("/(\\\\)?u(\\\\)?r(\\\\)?l(\\\\)?/i",'url', $content);
preg_match_all("/url\s*$(.+)$/si",$content,$aMatch);
if (count($aMatch)) {
$aValue = $aReplace = array();
foreach($aMatch[1] as $sMatch) {
// url value
$urlvalue = $sMatch;
sq_fix_url('style',$urlvalue, $message, $id, $mailbox,"'");
$aValue[] = $sMatch;
$aReplace[] = $urlvalue;
}
$content = str_replace($aValue,$aReplace,$content);
}
/**
* Remove any backslashes, entities, and extraneous whitespace.
*/
$contentTemp = $content;
sq_defang($contentTemp);
sq_unspace($contentTemp);
/**
* Fix stupid css declarations which lead to vulnerabilities
* in IE.
*
* Also remove "position" attribute, as it can easily be set
* to "fixed" or "absolute" with "left" and "top" attributes
* of zero, taking over the whole content frame. It can also
* be set to relative and move itself anywhere it wants to,
* displaying content in areas it shouldn't be allowed to touch.
*/
$match = Array('/\/\*.*\*\//', // removes /* blah blah */
'/expression/i',
'/behaviou*r/i',
'/binding/i',
'/include-source/i',
'/javascript/i',
'/script/i',
'/position/i');
$replace = Array('','idiocy', 'idiocy', 'idiocy', 'idiocy', 'idiocy', 'idiocy', '');
$contentNew = preg_replace($match, $replace, $contentTemp);
if ($contentNew !== $contentTemp) {
// insecure css declarations are used. From now on we don't care
// anymore if the css is destroyed by sq_deent, sq_unspace or sq_unbackslash
$content = $contentNew;
}
return array($content, $newpos);
}
/**
* This function converts cid: url's into the ones that can be viewed in
* the browser.
*
* @param $message the message object
* @param $id the message id
* @param $cidurl the cid: url.
* @param $mailbox the message mailbox
* @return a string with a http-friendly url
*/
function sq_cid2http($message, $id, $cidurl, $mailbox){
/**
* Get rid of quotes.
*/
$quotchar = substr($cidurl, 0, 1);
if ($quotchar == '"' || $quotchar == "'"){
$cidurl = str_replace($quotchar, "", $cidurl);
} else {
$quotchar = '';
}
$cidurl = substr(trim($cidurl), 4);
$match_str = '/\{.*?\}\//';
$str_rep = '';
$cidurl = preg_replace($match_str, $str_rep, $cidurl);
$linkurl = find_ent_id($cidurl, $message);
/* in case of non-safe cid links $httpurl should be replaced by a sort of
unsafe link image */
$httpurl = '';
/**
* This is part of a fix for Outlook Express 6.x generating
* cid URLs without creating content-id headers. These images are
* not part of the multipart/related html mail. The html contains
* <img src="cid:{some_id}/image_filename.ext"> references to
* attached images with as goal to render them inline although
* the attachment disposition property is not inline.
*/
if (empty($linkurl)) {
if (preg_match('/{.*}\//', $cidurl)) {
$cidurl = preg_replace('/{.*}\//','', $cidurl);
if (!empty($cidurl)) {
$linkurl = find_ent_id($cidurl, $message);
}
}
}
if (!empty($linkurl)) {
$httpurl = $quotchar . SM_PATH . 'src/download.php?absolute_dl=true&' .
"passed_id=$id&mailbox=" . urlencode($mailbox) .
'&ent_id=' . $linkurl . $quotchar;
} else {
/**
* If we couldn't generate a proper img url, drop in a blank image
* instead of sending back empty, otherwise it causes unusual behaviour
*/
$httpurl = $quotchar . SM_PATH . 'images/blank.png' . $quotchar;
}
return $httpurl;
}
/**
* This function changes the <body> tag into a <div> tag since we
* can't really have a body-within-body.
*
* @param $attary an array of attributes and values of <body>
* @param $mailbox mailbox we're currently reading (for cid2http)
* @param $message current message (for cid2http)
* @param $id current message id (for cid2http)
* @return a modified array of attributes to be set for <div>
*/
function sq_body2div($attary, $mailbox, $message, $id){
$me = 'sq_body2div';
$divattary = Array('class' => "'bodyclass'");
$bgcolor = '#ffffff';
$text = '#000000';
$styledef = '';
if (is_array($attary) && sizeof($attary) > 0){
foreach ($attary as $attname=>$attvalue){
$quotchar = substr($attvalue, 0, 1);
$attvalue = str_replace($quotchar, "", $attvalue);
switch ($attname){
case 'background':
$attvalue = sq_cid2http($message, $id, $attvalue, $mailbox);
$styledef .= "background-image: url('$attvalue'); ";
break;
case 'bgcolor':
$styledef .= "background-color: $attvalue; ";
break;
case 'text':
$styledef .= "color: $attvalue; ";
break;
}
}
if (strlen($styledef) > 0){
$divattary{"style"} = "\"$styledef\"";
}
}
return $divattary;
}
/**
* This is the main function and the one you should actually be calling.
* There are several variables you should be aware of an which need
* special description.
*
* Since the description is quite lengthy, see it here:
* http://linux.duke.edu/projects/mini/htmlfilter/
*
* @param $body the string with HTML you wish to filter
* @param $tag_list see description above
* @param $rm_tags_with_content see description above
* @param $self_closing_tags see description above
* @param $force_tag_closing see description above
* @param $rm_attnames see description above
* @param $bad_attvals see description above
* @param $add_attr_to_tag see description above
* @param $message message object
* @param $id message id
* @param $recursively_called boolean flag for recursive calls into this function (optional; default FALSE)
* @return sanitized html safe to show on your pages.
*/
function sq_sanitize($body,
$tag_list,
$rm_tags_with_content,
$self_closing_tags,
$force_tag_closing,
$rm_attnames,
$bad_attvals,
$add_attr_to_tag,
$message,
$id,
$mailbox,
$recursively_called=FALSE
){
$me = 'sq_sanitize';
/**
* See if tag_list is of tags to remove or tags to allow.
* false means remove these tags
* true means allow these tags
*/
$orig_tag_list = $tag_list;
$rm_tags = array_shift($tag_list);
/**
* Normalize rm_tags and rm_tags_with_content.
*/
@array_walk($tag_list, 'sq_casenormalize');
@array_walk($rm_tags_with_content, 'sq_casenormalize');
@array_walk($self_closing_tags, 'sq_casenormalize');
$curpos = 0;
$open_tags = Array();
$trusted = "\n\n";
$skip_content = false;
/**
* Take care of netscape's stupid javascript entities like
* &{alert('boo')};
*/
$body = preg_replace("/&(\{.*?\};)/si", "&\\1", $body);
while (($curtag = sq_getnxtag($body, $curpos)) != FALSE){
list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
/**
* RCDATA and RAWTEXT tags are handled differently:
* next instance of closing tag is used, whether or not
* the HTML is well formed before that
*/
global $rcdata_rawtext_tags;
if (!$recursively_called
&& in_array($tagname, $rcdata_rawtext_tags)
&& $tagtype === 1){
$closing_tag = false;
$closing_tag_offset = $curpos;
// seek out the closing tag for the current RCDATA/RAWTEXT tag
while (1) {
// first we need to move forward to next available closing tag
// (intentionally leave off the closing > and let sq_getnxtag() validate a proper tag syntax)
$next_tag = sq_findnxreg($body, $closing_tag_offset, "</\s*$tagname");
if ($next_tag === false) {
$closing_tag = false;
break;
}
// but then we have to make sure it's a well-formed tag
$closing_tag = sq_getnxtag($body, $next_tag[0]);
if ($closing_tag === false)
break;
else if ($closing_tag[0] !== false
// these should be redundant
&& $closing_tag[0] === $tagname && $closing_tag[2] === 2) {
$trusted .= sq_sanitize(substr($body, $curpos, $closing_tag[4] - $curpos + 1),
$orig_tag_list, $rm_tags_with_content, $self_closing_tags,
$force_tag_closing, $rm_attnames, $bad_attvals, $add_attr_to_tag,
$message, $id, $mailbox, true);
$curpos = $closing_tag[4] + 1;
continue 2;
}
$closing_tag_offset = $next_tag[0] + 1;
}
if ($closing_tag === false)
{ /* no-op... there was no closing tag for this RCDATA/RAWTEXT tag - we could probably set $curpos to the end of $body, but this HTML is malformed anyway and should just fall apart on its own */ }
}
$free_content = substr($body, $curpos, $lt-$curpos);
/**
* Take care of <style>
*/
if ($tagname == "style" && $tagtype == 1){
list($free_content, $curpos) =
sq_fixstyle($body, $gt+1, $message, $id, $mailbox);
if ($free_content != FALSE){
if ( !empty ($attary) ) {
$attary = sq_fixatts($tagname,
$attary,
$rm_attnames,
$bad_attvals,
$add_attr_to_tag,
$message,
$id,
$mailbox
);
}
$trusted .= sq_tagprint($tagname, $attary, $tagtype);
$trusted .= $free_content;
$trusted .= sq_tagprint($tagname, false, 2);
}
continue;
}
if ($skip_content == false){
$trusted .= $free_content;
}
if ($tagname != FALSE){
if ($tagtype == 2){
if ($skip_content == $tagname){
/**
* Got to the end of tag we needed to remove.
*/
$tagname = false;
$skip_content = false;
} else {
if ($skip_content == false){
if ($tagname == "body"){
$tagname = "div";
}
if (isset($open_tags{$tagname}) &&
$open_tags{$tagname} > 0){
$open_tags{$tagname}--;
} else {
$tagname = false;
}
}
}
} else {
/**
* $rm_tags_with_content
*/
if ($skip_content == false){
/**
* See if this is a self-closing type and change
* tagtype appropriately.
*/
if ($tagtype == 1
&& in_array($tagname, $self_closing_tags)){
$tagtype = 3;
}
/**
* See if we should skip this tag and any content
* inside it.
*/
if ($tagtype == 1 &&
in_array($tagname, $rm_tags_with_content)){
$skip_content = $tagname;
} else {
if (($rm_tags == false
&& in_array($tagname, $tag_list)) ||
($rm_tags == true &&
!in_array($tagname, $tag_list))){
$tagname = false;
} else {
/**
* Convert body into div.
*/
if ($tagname == "body"){
$tagname = "div";
$attary = sq_body2div($attary, $mailbox,
$message, $id);
}
if ($tagtype == 1){
if (isset($open_tags{$tagname})){
$open_tags{$tagname}++;
} else {
$open_tags{$tagname}=1;
}
}
/**
* This is where we run other checks.
*/
if (is_array($attary) && sizeof($attary) > 0){
$attary = sq_fixatts($tagname,
$attary,
$rm_attnames,
$bad_attvals,
$add_attr_to_tag,
$message,
$id,
$mailbox
);
}
}
}
}
}
if ($tagname != false && $skip_content == false){
$trusted .= sq_tagprint($tagname, $attary, $tagtype);
}
}
$curpos = $gt+1;
}
$trusted .= substr($body, $curpos, strlen($body)-$curpos);
if ($force_tag_closing == true){
foreach ($open_tags as $tagname=>$opentimes){
while ($opentimes > 0){
$trusted .= '</' . $tagname . '>';
$opentimes--;
}
}
$trusted .= "\n";
}
$trusted .= "\n";
return $trusted;
}
/**
* This is a wrapper function to call html sanitizing routines.
*
* @param $body the body of the message
* @param $id the id of the message
* @param boolean $take_mailto_links When TRUE, converts mailto: links
* into internal SM compose links
* (optional; default = TRUE)
* @return a string with html safe to display in the browser.
*/
function magicHTML($body, $id, $message, $mailbox = 'INBOX', $take_mailto_links =true) {
require_once(SM_PATH . 'functions/url_parser.php'); // for $MailTo_PReg_Match
global $attachment_common_show_images, $view_unsafe_images,
$has_unsafe_images, $allow_svg_display, $rcdata_rawtext_tags,
$remove_rcdata_rawtext_tags_and_content;
$rcdata_rawtext_tags = array(
"noscript",
"noframes",
"noembed",
"textarea",
// also "title", "xmp", "script", "iframe", "plaintext" which we already remove below
);
/**
* Don't display attached images in HTML mode.
*/
$attachment_common_show_images = false;
$tag_list = Array(
false, // remove these tags
"meta",
"html",
"head",
"base",
"link",
"frame",
"iframe",
"plaintext",
"marquee",
);
$rm_tags_with_content = Array(
"script",
"object",
"applet",
"embed",
"title",
"frameset",
"xmp",
"xml",
);
if (!$allow_svg_display)
$rm_tags_with_content[] = 'svg';
/**
* SquirrelMail will parse RCDATA and RAWTEXT tags and handle them as the special
* case that they are, but if you prefer to remove them and their contents entirely
* (in most cases, should be a safe thing with minimal impact), you can add the
* following to config/config_local.php
* $remove_rcdata_rawtext_tags_and_content = TRUE;
*/
if ($remove_rcdata_rawtext_tags_and_content)
$rm_tags_with_content = array_merge($rm_tags_with_content, $rcdata_rawtext_tags);
$self_closing_tags = Array(
"img",
"br",
"hr",
"input",
"outbind",
);
$force_tag_closing = true;
$rm_attnames = Array(
"/.*/" =>
Array(
"/target/i",
"/^on.*/i",
"/^dynsrc/i",
"/^data.*/i",
"/^lowsrc.*/i",
)
);
global $use_transparent_security_image;
if ($use_transparent_security_image) $secremoveimg = '../images/spacer.png';
else $secremoveimg = '../images/' . _("sec_remove_eng.png");
$bad_attvals = Array(
"/.*/" =>
Array(
"/^src|background/i" =>
Array(
Array(
"/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
"/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
"/^([\'\"])\s*about\s*:.*([\'\"])/si"
),
Array(
"\\1$secremoveimg\\2",
"\\1$secremoveimg\\2",
"\\1$secremoveimg\\2"
)
),
"/^href|action/i" =>
Array(
Array(
"/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
"/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
"/^([\'\"])\s*about\s*:.*([\'\"])/si"
),
Array(
"\\1#\\1",
"\\1#\\1",
"\\1#\\1"
)
),
"/^style/i" =>
Array(
Array(
"/\/\*.*\*\//",
"/expression/i",
"/binding/i",
"/behaviou*r/i",
"/include-source/i",
// position:relative can also be exploited
// to put content outside of email body area
// and position:fixed is similarly exploitable
// as position:absolute, so we'll remove it
// altogether....
//
// Does this screw up legitimate HTML messages?
// If so, the only fix I see is to allow position
// attributes (any values? I think we still have
// to block static and fixed) only if $use_iframe
// is enabled (1.5.0+)
//
// was: "/position\s*:\s*absolute/i",
//
"/position\s*:/i",
"/(\\\\)?u(\\\\)?r(\\\\)?l(\\\\)?/i",
"/url\s*$\s*([\'\"])\s*\S+script\s*:.*([\'\"])\s*$/si",
"/url\s*$\s*([\'\"])\s*mocha\s*:.*([\'\"])\s*$/si",
"/url\s*$\s*([\'\"])\s*about\s*:.*([\'\"])\s*$/si",
"/(.*)\s*:\s*url\s*$\s*([\'\"]*)\s*\S+script\s*:.*([\'\"]*)\s*$/si",
),
Array(
"",
"idiocy",
"idiocy",
"idiocy",
"idiocy",
"idiocy",
"url",
"url(\\1#\\1)",
"url(\\1#\\1)",
"url(\\1#\\1)",
"\\1:url(\\2#\\3)"
)
)
)
);
// If there's no "view_unsafe_images" variable in the URL, turn unsafe
// images off by default.
if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
$view_unsafe_images = false;
}
if (!$view_unsafe_images){
/**
* Remove any references to http/https if view_unsafe_images set
* to false.
*/
array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
'/^([\'\"])\s*https*:.*([\'\"])/si');
array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
"\\1$secremoveimg\\1");
array_push($bad_attvals{'/.*/'}{'/^style/i'}[0],
'/url$[\'\"]?https?:[^$]*[\'\"]?\)/si');
array_push($bad_attvals{'/.*/'}{'/^style/i'}[1],
"url(\\1$secremoveimg\\1)");
}
$add_attr_to_tag = Array(
"/^a$/i" =>
Array('target'=>'"_blank"',
'title'=>'"'._("This external link will open in a new window").'"'
)
);
$trusted = sq_sanitize($body,
$tag_list,
$rm_tags_with_content,
$self_closing_tags,
$force_tag_closing,
$rm_attnames,
$bad_attvals,
$add_attr_to_tag,
$message,
$id,
$mailbox
);
if (strpos($trusted,$secremoveimg)){
$has_unsafe_images = true;
}
// we want to parse mailto's in HTML output, change to SM compose links
// this is a modified version of code from url_parser.php... but Marc is
// right: we need a better filtering implementation; adding this randomly
// here is not a great solution
//
if ($take_mailto_links) {
// parseUrl($trusted); // this even parses URLs inside of tags... too aggressive
global $MailTo_PReg_Match;
// some mailers (Microsoft, surprise surprise) produce mailto strings without being
// inside an anchor (link) tag, so we have to make sure the regex looks for the
// quote before mailto, and we'll also try to convert the non-links back into links
$MailTo_PReg_Match = '/([\'"])?mailto:' . substr($MailTo_PReg_Match, 1) ;
if ((preg_match_all($MailTo_PReg_Match, $trusted, $regs)) && ($regs[0][0] != '')) {
foreach ($regs[0] as $i => $mailto_before) {
$mailto_params = $regs[11][$i];
// get rid of any leading quote we may have captured but don't care about
//
$mailto_before = ltrim($mailto_before, '"\'');
// get rid of any tailing quote since we have to add send_to to the end
//
$mailto_before = rtrim($mailto_before, '"\'');
$mailto_params = rtrim($mailto_params, '"\'');
if ($regs[2][$i]) { //if there is an email addr before '?', we need to merge it with the params
$to = 'to=' . $regs[2][$i];
if (strpos($mailto_params, 'to=') > -1) //already a 'to='
$mailto_params = str_replace('to=', $to . '%2C%20', $mailto_params);
else {
if ($mailto_params) //already some params, append to them
$mailto_params .= '&' . $to;
else
$mailto_params .= '?' . $to;
}
}
$url_str = preg_replace(array('/to=/i', '/(?<!b)cc=/i', '/bcc=/i'), array('send_to=', 'send_to_cc=', 'send_to_bcc='), $mailto_params);
// we'll already have target=_blank, no need to allow comp_in_new
// here (which would be a lot more work anyway)
//
global $compose_new_win;
$temp_comp_in_new = $compose_new_win;
$compose_new_win = 0;
$comp_uri = makeComposeLink('src/compose.php' . $url_str, $mailto_before);
$compose_new_win = $temp_comp_in_new;
// remove <a href=" and anything after the next quote (we only
// need the uri, not the link HTML) in compose uri
//
// but only do this if the original mailto was in a real anchor tag
//
if (!empty($regs[1][$i])) {
$comp_uri = substr($comp_uri, 9);
$comp_uri = substr($comp_uri, 0, strpos($comp_uri, '"', 1));
}
$trusted = str_replace($mailto_before, $comp_uri, $trusted);
}
}
}
return $trusted;
}
/**
* function SendDownloadHeaders - send file to the browser
*
* Original Source: SM core src/download.php
* moved here to make it available to other code, and separate
* front end from back end functionality.
*
* @param string $type0 first half of mime type
* @param string $type1 second half of mime type
* @param string $filename filename to tell the browser for downloaded file
* @param boolean $force whether to force the download dialog to pop
* @param optional integer $filesize send the Content-Header and length to the browser
* @return void
*/
function SendDownloadHeaders($type0, $type1, $filename, $force, $filesize=0) {
global $languages, $squirrelmail_language;
$isIE = $isIE6plus = false;
sqgetGlobalVar('HTTP_USER_AGENT', $HTTP_USER_AGENT, SQ_SERVER);
if (strstr($HTTP_USER_AGENT, 'compatible; MSIE ') !== false &&
strstr($HTTP_USER_AGENT, 'Opera') === false) {
$isIE = true;
}
if (preg_match('/compatible; MSIE ([0-9]+)/', $HTTP_USER_AGENT, $match) &&
((int)$match[1]) >= 6 && strstr($HTTP_USER_AGENT, 'Opera') === false) {
$isIE6plus = true;
}
if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
$filename =
$languages[$squirrelmail_language]['XTRA_CODE']('downloadfilename', $filename, $HTTP_USER_AGENT);
} else {
$filename = preg_replace('/[\\\\\/:*?"<>|;]/', '_', str_replace(' ', ' ', $filename));
}
// A Pox on Microsoft and it's Internet Explorer!
//
// IE has lots of bugs with file downloads.
// It also has problems with SSL. Both of these cause problems
// for us in this function.
//
// See this article on Cache Control headers and SSL
// http://support.microsoft.com/default.aspx?scid=kb;en-us;323308
//
// The best thing you can do for IE is to upgrade to the latest
// version
//set all the Cache Control Headers for IE
if ($isIE) {
$filename=rawurlencode($filename);
header ("Pragma: public");
header ("Cache-Control: no-store, max-age=0, no-cache, must-revalidate"); // HTTP/1.1
// does nothing - see: https://blogs.msdn.microsoft.com/ieinternals/2009/07/20/internet-explorers-cache-control-extensions/
// header ("Cache-Control: post-check=0, pre-check=0", false);
header ("Cache-Control: private");
//set the inline header for IE, we'll add the attachment header later if we need it
header ("Content-Disposition: inline; filename=$filename");
}
if (!$force) {
// Try to show in browser window
header ("Content-Disposition: inline; filename=\"$filename\"");
header ("Content-Type: $type0/$type1; name=\"$filename\"");
} else {
// Try to pop up the "save as" box
// IE makes this hard. It pops up 2 save boxes, or none.
// http://support.microsoft.com/support/kb/articles/Q238/5/88.ASP
// http://support.microsoft.com/default.aspx?scid=kb;EN-US;260519
// But, according to Microsoft, it is "RFC compliant but doesn't
// take into account some deviations that allowed within the
// specification." Doesn't that mean RFC non-compliant?
// http://support.microsoft.com/support/kb/articles/Q258/4/52.ASP
// all browsers need the application/octet-stream header for this
header ("Content-Type: application/octet-stream; name=\"$filename\"");
// http://support.microsoft.com/support/kb/articles/Q182/3/15.asp
// Do not have quotes around filename, but that applied to
// "attachment"... does it apply to inline too?
header ("Content-Disposition: attachment; filename=\"$filename\"");
if ($isIE && !$isIE6plus) {
// This combination seems to work mostly. IE 5.5 SP 1 has
// known issues (see the Microsoft Knowledge Base)
// This works for most types, but doesn't work with Word files
header ("Content-Type: application/download; name=\"$filename\"");
// This is to prevent IE for MIME sniffing and auto open a file in IE
header ("Content-Type: application/force-download; name=\"$filename\"");
// These are spares, just in case. :-)
//header("Content-Type: $type0/$type1; name=\"$filename\"");
//header("Content-Type: application/x-msdownload; name=\"$filename\"");
//header("Content-Type: application/octet-stream; name=\"$filename\"");
} else if ($isIE) {
// This is to prevent IE for MIME sniffing and auto open a file in IE
header ("Content-Type: application/force-download; name=\"$filename\"");
} else {
// another application/octet-stream forces download for Netscape
header ("Content-Type: application/octet-stream; name=\"$filename\"");
}
}
//send the content-length header if the calling function provides it
if ($filesize > 0) {
header("Content-Length: $filesize");
}
} // end fn SendDownloadHeaders

Documentation generated on Mon, 13 Jan 2020 04:25:01 +0100 by phpDocumentor 1.4.3

Source for file mime.php