crypt-blowfish returns *0 rather than hash

[photodude]

Expected this issue to have been fixed as noted in #1071
Still getting *0 as return

HHVM Version

3.15.2
3.16.0-dev

Standalone code, or other way to reproduce the problem

<?php
    function getCryptedPassword($plaintext, $salt = '', $encryption = 'crypt-blowfish', $show_encrypt = false)
    {
        // mimic the getSalt function so we can use it in the example.
        if ($salt)
        {
            $salt = substr(preg_replace('|^{crypt}|i', '', $salt), 0, 16);
        }
        else
        {
            if (function_exists('random_bytes'))
            {
                $salt = '$2$' . substr(md5(random_bytes(16)), 0, 12) . '$';
            }
            else
            {
                // Fake the salt result (a previously generated salt using https://github.com/paragonie/random_compat )
                $salt = '$2$9936b047ea8b$';
            }
        }
        // Encrypt the password.
        switch ($encryption)
        {
            case 'plain':
                return $plaintext;
            case 'sha':
                $encrypted = base64_encode(mhash(MHASH_SHA1, $plaintext));
                return ($show_encrypt) ? '{SHA}' . $encrypted : $encrypted;
            case 'crypt':
            case 'crypt-des':
            case 'crypt-md5':
            case 'crypt-blowfish':
                return ($show_encrypt ? '{crypt}' : '') . crypt($plaintext, $salt);
            case 'md5-hex':
            default:
                $encrypted = ($salt) ? md5($plaintext . $salt) : md5($plaintext);
                return ($show_encrypt) ? '{MD5}' . $encrypted : $encrypted;
        }
    }
$plaintext = 'mySuperSecretPassword';

if (function_exists('random_bytes'))
{
    $salt = '$2$' . substr(md5(random_bytes(16)), 0, 12) . '$';
}
else
{
    // Fake the salt result (a randomly created salt using https://github.com/paragonie/random_compat )
    $salt = '$2$9936b047ea8b$';
}

echo strlen(crypt($plaintext, $salt)) . "\n";
echo crypt($plaintext, $salt) . "\n";
echo strlen(getCryptedPassword($plaintext, $salt, 'crypt-blowfish')) . "\n";
echo getCryptedPassword($plaintext, $salt, 'crypt-blowfish');

More test code from https://github.com/facebook/hhvm/blob/master/hphp/test/zend/bad/ext/standard/tests/strings/crypt_blowfish_variation2.php

<?php
$crypt = crypt(b'U*U', b'$2a$CCCCCCCCCCCCCCCCCCCCC.E5YPO9kmyuRGyh0XouQYb4YMJKvyOeW');
if ($crypt===b'$2SHYF.wPGyfE') {
    echo "OK\n"; // This is the expected result
} else {
    echo "Not OK\n"; // This is a Failure
}
?>

https://3v4l.org/GOZIG

Expected result

a hash of length 13 should be returned from crypt()

Actual result

return is just *0 a value indicating a failure

• https://3v4l.org/qBAIU
  • See Travis build for 3.15.2
• https://travis-ci.org/photodude/joomla-cms/jobs/167966010#L1239-L1240
  • See Travis build for 3.16.0-dev
• https://travis-ci.org/photodude/joomla-cms/jobs/167966012#L1184-L1185

[Orvid]

I see the cause, will put up a diff tomorrow.

[photodude]

Thanks @Orvid I look forward to the fix.

[Orvid]

Hrmmm... It actually looks like PHP 7 actually changed this behavior: https://3v4l.org/5tIPh

The key that's being provided says it's blowfish (the $2a$), but is then missing the number of rounds of hashing, which is supposed to come immediately after the hash type. $2a$10$ would be a valid prefix.

The behavior of getting a hash back is the result of it falling back to DES in that case, which php/php-src@4a2fe3d changed.

[photodude]

@Orvid since the behavior has changed in PHP 7, maybe this issue can be closed as a "won't fix".

From our end it causes a failure in our old password encryption method which was replaced with the newer PHP password hash. The old method is only implemented as a bc for upgrades in the 3.x versions and has been dropped in 4.0-dev.

Thoughts?

[photodude]

@Orvid I've run into another issue with this. Apparently, if there is a case needing to verify a crypt() hashed text it will fail.

example code

$password = 'mySuperSecretPassword';
$hash = '$2xzaiMREaf7o';

$valid = hash_equals(crypt($password, $hash), $hash);

if ($valid === true)
{
    echo "OK\n"; // This is the expected result
}
else
{
    echo "Not OK\n"; // This is a Failure
}

https://3v4l.org/LI9VY

Note in php 7.0-7.1 the result is OK with a notice about Deprecated: crypt(): Supplied salt is not valid for DES. Possible bug in provided salt format. where HHVM fails this kind of verification test

[photodude]

Still an issue in HHVM 3.19.0
https://3v4l.org/LI9VY

also differs from PHP 7 @Orvid please add the php 7 incompatibility tag here

[photodude]

closing as per https://hhvm.com/blog/2017/09/18/the-future-of-hhvm.html