Edit report at http://bugs.php.net/bug.php?id=52327&edit=1
ID: 52327
Updated by: il...@php.net
Reported by: yuri-sevatz at hotmail dot com
Summary: base64_decode() improper handling of leading
padding.
-Status: Assigned
+Status: Closed
Type: Bug
Package: *Compression related
Operating System: ALL
PHP Version: 5.3.2
Assigned To: iliaa
Block user comment: N
Private report: N
New Comment:
This bug has been fixed in SVN.
Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
Thank you for the report, and for helping us make PHP better.
Fixed when strict mode is being used.
Previous Comments:
------------------------------------------------------------------------
[2010-11-26 21:59:15] il...@php.net
Automatic comment from SVN on behalf of iliaa
Revision: http://svn.php.net/viewvc/?view=revision&revision=305779
Log: Fixed bug #52327 (base64_decode() improper handling of leading
padding in strict mode)
------------------------------------------------------------------------
[2010-07-13 11:12:17] yuri-sevatz at hotmail dot com
Description:
------------
According to the MIME standard that we're following, this isn't supposed
to work when strict mode is enabled. Equal-signs are strictly reserved
for padding characters at the _end_ of a base64 MIME string.
Leading '=' signs are allowed in each block of 4 bytes because the
condition that checks for invalid placement of the '=' signs only checks
if (i % 4) == 1,
Whereas it should check if (i % 4) is 0 or 1.
You should be able to change the circumstances for a valid '='
placement, as follows, to conform to the standard:
// to see if bit position 2 is set (for all values of i = n*4+2 and i =
n*4+3)
if (i & 2)
// means that the '=' is in a valid location
I would also suggest *carefully* looking over the block at the end of
the base64_decode() function... as it seems that if (ch == base64_pad)
after ch is ALWAYS set to '\0' is an impossible scenario.
Test script:
---------------
<?php
echo
base64_decode('=VGhl=ICc9=JyBz=eW1i=b2xz=IGFy=ZW4n=dCBh=bGxv=d2Vk=IHdo=ZXJl=IGkg=cHV0=IHRo=ZW0g=by5P');
?>
Expected result:
----------------
should return FALSE/NULL/Errornous value
Actual result:
--------------
echos:
The '=' symbols aren't allowed where i put them o.O
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Edit this bug report at http://bugs.php.net/bug.php?id=52327&edit=1
