Edit report at http://bugs.php.net/bug.php?id=51282&edit=1
ID: 51282
Updated by: j...@php.net
Reported by: jerome dot auge at anakeen dot com
Summary: crypt() result different between PHP 5.3.1 and PHP
5.3.2
Status: Bogus
Type: Documentation Problem
Package: *Encryption and hash functions
Operating System: Mac, Linux
PHP Version: 5.3.2
Assigned To: joey
New Comment:
Paul:
Yes, it's definitely undefined behaviour. However, I can't duplicate
this - are
you using 5.3.0 and 5.2.8 on different operating systems? Prior to
5.3.2, PHP
would call the underlying OS's crypt() - so, on platforms that use the
"UFC"
crypt() (Linux, Sun, certain BSDs) you might get a different result than
ones that
use the FreeSec 1.0 crypt() (Mac OS X, OpenBSD).
Previous Comments:
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[2010-03-30 23:35:58] paul dot fernandez at gmail dot com
You are correct. When I switched to using a two character alpha-numeric
salt, both PHP 5.2.8 and 5.3.0 returned the same encrypted string.
However, if I use a one character alpha-numeric salt, I get a different
result on PHP 5.2.8 and 5.3.0:
<?php
$password = 'password';
$salt = 'a';
$des_pass = crypt($password, $salt);
echo "DES encryption (salt = $salt) = $des_pass\n";
?>
PHP 5.2.8:
$ php test27.php
DES encryption (salt = a) = a$LHSkrbhfU1.
PHP 5.3.0:
$ php test27.php
DES encryption (salt = a) = a$Av8awQ0AsR6
I wouldn't ordinarily break the rules, so-to-speak, by using a one
character salt, but I'm trying to match an encryption created by a one
character salt. Is this also producing undefined behavior because of
the shortness of the salt?
Thanks
------------------------------------------------------------------------
[2010-03-30 01:53:42] j...@php.net
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to report
a bug at http://bugs.php.net/how-to-report.php
The salt has to come from the alphabet "./0-9A-Za-z", and using
characters outside this range will result in undefined behaviour. As of
5.3.1, this is handled by not using the illegal characters as part of
key in order to have consistent behaviour on all platforms.
cf:
http://www.gnu.org/s/libc/manual/html_node/crypt.html
http://www.manpages.info/freebsd/crypt.3.html
http://docs.sun.com/app/docs/doc/816-5175/crypt-unix-5?l=en&a=view
------------------------------------------------------------------------
[2010-03-30 00:53:52] paul dot fernandez at gmail dot com
I have a similar problem going from PHP 5.2.8 to 5.3.0.
<?php
if(CRYPT_STD_DES == 1) { echo "Standard DES is available.\n\n";
}
$username = 'aardvark';
$password = 'password';
$salt = substr($username, 0, 1);
echo "\$salt = $salt\n";
$pass = crypt($password, $salt);
echo "Standard crypt encryption (1 char salt) = '$pass'\n";
$des_pass = crypt($password, 'a$');
echo "DES encryption (2 char salt) = '$des_pass'\n";
?>
Output from PHP 5.3.0:
$ php test24.php
Standard DES is available.
$salt = a
Standard crypt encryption (1 char salt) = 'a$Av8awQ0AsR6'
DES encryption (2 char salt) = 'a$Av8awQ0AsR6'
Output of the same code on PHP 5.2.8:
$ php test24.php
Standard DES is available.
$salt = a
Standard crypt encryption (1 char salt) = 'a$LHSkrbhfU1.'
DES encryption (2 char salt) = 'a$LHSkrbhfU1.'
------------------------------------------------------------------------
[2010-03-12 10:54:22] jerome dot auge at anakeen dot com
Description:
------------
I use crypt() to store and validate passwords using the « Standard DES
» hash, and after upgrading to 5.3.2, the hashed password of an account
is not the same as the one generated with PHP 5.3.1 :
With PHP 5.3.1 :
$ php -r 'print crypt("anakeen", "A^")."\n";'
A^1ul2Jf7VS2M
After upgrading to PHP 5.3.2 :
$ php -r 'print crypt("anakeen", "A^")."\n";'
A^/ImZ5hqd2VU
I tested both on Mac (macports) and on Linux (rawhide), and the hash
result was different on both platform.
On Mac OS X (10.5), the Perl (or C) crypt gives me the same results as
PHP 5.3.1 :
$ perl -e 'print crypt("anakeen", "A^")."\n";'
A^1ul2Jf7VS2M
While on Linux, the Perl script gives me the same result as PHP 5.3.2.
It appears that there is a difference in the crypt() function, between
these platforms, regarding the presence of non alpha-num chars in the
salt :
Mac OS X with "A-" salt = different hashes :
$ php -r 'print crypt("anakeen", "A-")."\n";'
A-75An91LCLEM
$ perl -e 'print crypt("anakeen", "A-")."\n"';
A-1ul2Jf7VS2M
Mac OS X with "A9" salt = same hashes :
$ perl -e 'print crypt("anakeen", "A9")."\n"';
A9Pf3.gAayQMM
$ php -r 'print crypt("anakeen", "A9")."\n";'
A9Pf3.gAayQMM
Maybe I should not have used non alpha-num chars for my salt in the
first place ?
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Edit this bug report at http://bugs.php.net/bug.php?id=51282&edit=1
