OoO En ce début de soirée du vendredi 28 décembre 2007, vers 21:45, je disais:
>> I found Squirrelmail's solution. They seem to use one function for every >> possible tag in the HTML source: >> http://osdir.com/ml/mail.squirrelmail.cvs/2006-12/msg00031.html >> I'll try to implement that, and/or search for more :) > Hi Robin ! > I noticed that you have posted a patch. I have tried it but it seems > that there is no effect. I have tried with ie6 from ie4linux and I still > get the javascript popups. Did you try it succesfully on rc2? > I have used the test message from here: > http://www.topolis.lt/bugtraq/expression.eml.gz I have tried with an up-to-date IE7 and the patch provided here does not fix the issue. In fact, the source code shows there is still unsanitized strings. I have completed the patch with a function from Squirrelmail (sq_defang). I have attached the complete patch.
pgpW5gGdX9dpV.pgp
Description: PGP signature
--- roundcube/program/steps/mail/func.inc 2007-10-17 08:50:28.000000000 +0200
+++ roundcube/program/steps/mail/func.inc 2008-01-22 21:59:30.000000000 +0100
@@ -481,6 +481,124 @@
return Q($out);
}
+/* Stolen from Squirrelmail */
+function sq_deent(&$attvalue, $regex, $hex=false){
+ $ret_match = false;
+ preg_match_all($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, $repl);
+ return true;
+ } else {
+ return false;
+ }
+}
+
+/* Stolen verbatim from Squirrelmail */
+function sq_defang(&$attvalue){
+ /**
+ * 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, '/\�*(\d+);*/s');
+ $m = $m || sq_deent($attvalue, '/\�*((\d|[a-f])+);*/si', true);
+ $m = $m || sq_deent($attvalue, '/\\\\(\d+)/s', true);
+ } while ($m == true);
+ $attvalue = stripslashes($attvalue);
+}
+
+function rcmail_html_filter($html)
+ {
+ preg_match_all('/<\/?\w+((\s+\w+(\s*=\s*(?:".*?"|\'.*?\'|[^\'">\s]+))?)+\s*|\s*)\/?>/', $html, $tags);
+
+ /* From Squirrelmail: Translate all dangerous Unicode or Shift_JIS characters which are accepted by
+ * IE as regular characters. */
+ $replace = 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'));
+ if ((count($tags)>3) && (count($tags[3])>0))
+ foreach ($tags[3] as $nr=>$value)
+ {
+ /* Remove comments */
+ $newvalue = preg_replace('/(\/\*.*\*\/)/','$2',$value);
+ /* Translate dangerous characters */
+ $newvalue = str_replace($replace[0], $replace[1], $newvalue);
+ sq_defang($newvalue);
+ /* Rename dangerous CSS */
+ $newvalue = preg_replace('/expression/i', 'idiocy', $newvalue);
+ $newvalue = preg_replace('/url/i', 'idiocy', $newvalue);
+ $newattrs = preg_replace('/'.preg_quote($value, '/').'$/', $newvalue, $tags[1][$nr]);
+ $newtag = preg_replace('/'.preg_quote($tags[1][$nr], '/').'/', $newattrs, $tags[0][$nr]);
+ $html = preg_replace('/'.preg_quote($tags[0][$nr], '/').'/', $newtag, $html);
+ }
+
+ return $html;
+ }
+
function rcmail_print_body($part, $safe=FALSE, $plain=FALSE)
{
@@ -533,7 +651,7 @@
$body = preg_replace($remote_patterns, $remote_replaces, $body);
}
- return Q($body, 'show', FALSE);
+ return Q(rcmail_html_filter($body), 'show', FALSE);
}
// text/enriched
There is still some unsanitized strings but IE does not trigger any
alert any more. We will use this patch as a temporary fix for Roundcube
Debian package unless you see a better way to handle this issue.
--
Treat end of file conditions in a uniform manner.
- The Elements of Programming Style (Kernighan & Plauger)
