egroupware/phpgwapi/inc/class.auth.inc.php

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2006-05-17 08:00:12 +02:00
<?php
/**
* eGroupWare API - Authentication baseclass
*
* @link http://www.egroupware.org
* @author Ralf Becker <ralfbecker@outdoor-training.de>
* @author Miles Lott <milos@groupwhere.org>
* @copyright 2004 by Miles Lott <milos@groupwhere.org>
* @license http://opensource.org/licenses/lgpl-license.php LGPL - GNU Lesser General Public License
* @package api
* @subpackage authentication
* @version $Id$
*/
// allow to set an application depending authentication type (eg. for syncml, groupdav, ...)
if (isset($GLOBALS['egw_info']['server']['auth_type_'.$GLOBALS['egw_info']['flags']['currentapp']]) &&
$GLOBALS['egw_info']['server']['auth_type_'.$GLOBALS['egw_info']['flags']['currentapp']])
{
$GLOBALS['egw_info']['server']['auth_type'] = $GLOBALS['egw_info']['server']['auth_type_'.$GLOBALS['egw_info']['flags']['currentapp']];
}
if(empty($GLOBALS['egw_info']['server']['auth_type']))
{
$GLOBALS['egw_info']['server']['auth_type'] = 'sql';
}
//error_log('using auth_type='.$GLOBALS['egw_info']['server']['auth_type'].', currentapp='.$GLOBALS['egw_info']['flags']['currentapp']);
/**
* eGroupWare API - Authentication baseclass, password auth and crypt functions
*
* Many functions based on code from Frank Thomas <frank@thomas-alfeld.de>
* which can be seen at http://www.thomas-alfeld.de/frank/
*
* Other functions from class.common.inc.php originally from phpGroupWare
*/
class auth
{
static $error;
/**
* Holds instance of backend
*
* @var auth_backend
*/
private $backend;
function __construct()
{
$backend_class = 'auth_'.$GLOBALS['egw_info']['server']['auth_type'];
$this->backend = new $backend_class;
if (!is_a($this->backend,'auth_backend'))
{
throw new egw_exception_assertion_failed("Auth backend class $backend_class is NO auth_backend!");
}
}
/**
* check_password_age
* check if users are supposed to change their password every x sdays, then check if password is of old age
* or the devil-admin reset the users password and forced the user to change his password on next login.
*
* @param string $app to know where you are/ or where you want to go
* @param string $class to know where you are/ or where you want to go
* @param string $method to know where you are/ or where you want to go
* @return boolean true if check determined, that you passed the test, otherwise void, as we get redirected
*/
static function check_password_age($app='', $class='', $method='')
{
// dont check anything for anonymous sessions/ users that are flagged as anonymous
if (is_object($GLOBALS['egw']->session) && $GLOBALS['egw']->session->session_flags == 'A') return true;
static $UserKnowsAboutPwdChange;
if (is_null($UserKnowsAboutPwdChange)) $UserKnowsAboutPwdChange =& egw_cache::getSession('phpgwapi','auth_UserKnowsAboutPwdChange');
// some statics to make information and timecalculation a) more readable in conditions b) persistent per request
static $alpwchange_val;
static $passwordAgeBorder;
static $daysLeftUntilChangeReq;
// current style name for account last password change timestamp
$alpwchange='account_lastpwd_change';
// some debug output and develop options to move the horizons and warn levels around
//$GLOBALS['egw_info']['server']['change_pwd_every_x_days'] =35;
//$GLOBALS['egw_info']['server']['warn_about_upcoming_pwd_change']=5;
//echo egw_time::to('now','ts').'<br>';
//echo "User changed password at:".egw_time::to($GLOBALS['egw_info']['user'][$alpwchange]).'<br>';
//echo "User password is ".((egw_time::to('now','ts')-$GLOBALS['egw_info']['user'][$alpwchange])/86400)." days old<br>";
//echo "Users must change passwords every ".$GLOBALS['egw_info']['server']['change_pwd_every_x_days'].' days ('.($GLOBALS['egw_info']['server']['change_pwd_every_x_days']*86400).') seconds.<br>';
//echo egw_time::to('now','ts')-($GLOBALS['egw_info']['server']['change_pwd_every_x_days']*86400).'<br>';
// if neither timestamp isset return true, nothing to do (exept this means the password is too old)
if (!isset($GLOBALS['egw_info']['user']['account_lastpasswd_change']) &&
!isset($GLOBALS['egw_info']['user'][$alpwchange]) &&
empty($GLOBALS['egw_info']['server']['change_pwd_every_x_days'])
) return true;
if ($GLOBALS['egw_info']['user']['account_lastpasswd_change'] && !$GLOBALS['egw_info']['user'][$alpwchange])
{
// use old style names, as the current one seems not to be set.
$alpwchange = 'account_lastpasswd_change';
}
// initalize statics - better readability of conditions
if (is_null($alpwchange_val))
{
$backend_class = 'auth_'.$GLOBALS['egw_info']['server']['auth_type'];
$backend = new $backend_class;
// this may change behavior, as it should detect forced PasswordChanges from your Authentication System too.
// on the other side, if your auth system does not require an forcedPasswordChange, you will not be asked.
if (method_exists($backend,'getLastPwdChange')) $alpwchange_val = $backend->getLastPwdChange($GLOBALS['egw_info']['user']['account_lid']);
if (is_null($alpwchange_val) || $alpwchange_val === false) $alpwchange_val = $GLOBALS['egw_info']['user'][$alpwchange];
}
if (is_null($passwordAgeBorder) && $GLOBALS['egw_info']['server']['change_pwd_every_x_days'])
{
$passwordAgeBorder = (egw_time::to('now','ts')-($GLOBALS['egw_info']['server']['change_pwd_every_x_days']*86400));
}
if (is_null($daysLeftUntilChangeReq) && $GLOBALS['egw_info']['server']['warn_about_upcoming_pwd_change'])
{
// maxage - passwordage = days left until change is required
$daysLeftUntilChangeReq = ($GLOBALS['egw_info']['server']['change_pwd_every_x_days'] - ((egw_time::to('now','ts')-$alpwchange_val)/86400));
}
//echo "Warn about the upcomming change ".$GLOBALS['egw_info']['server']['warn_about_upcoming_pwd_change'].' days before that time is reached<br>';
//$result = $GLOBALS['egw_info']['server']['change_pwd_every_x_days'] - $daysLeftUntilChangeReq;
//echo $GLOBALS['egw_info']['server']['change_pwd_every_x_days'].' - '.$daysLeftUntilChangeReq.'='. $result.'<br>';
if (!($app == 'preferences' && $class == 'uipassword' && $method=='change') &&
(
($GLOBALS['egw_info']['server']['change_pwd_every_x_days'] &&
($GLOBALS['egw_info']['user']['apps']['preferences'] || $GLOBALS['egw_info']['user']['apps']['password']) &&
(
($passwordAgeBorder > $alpwchange_val) ||
(
$GLOBALS['egw_info']['server']['warn_about_upcoming_pwd_change'] &&
$GLOBALS['egw_info']['server']['warn_about_upcoming_pwd_change'] > $daysLeftUntilChangeReq
)
)
) || $alpwchange_val==0
)
)
{
if ($GLOBALS['egw']->acl->check('nopasswordchange', 1, 'preferences')) return true; // user has no rights to change password
if ($UserKnowsAboutPwdChange === true && !($passwordAgeBorder > $alpwchange_val || $alpwchange_val==0)) return true; // user has already been informed about the upcomming password expiration
if ($alpwchange_val == 0)
{
$message = lang('an admin required that you must change your password upon login.');
}
elseif (($passwordAgeBorder < $alpwchange_val) ||
(
$GLOBALS['egw_info']['server']['warn_about_upcoming_pwd_change'] &&
$GLOBALS['egw_info']['server']['warn_about_upcoming_pwd_change'] > $daysLeftUntilChangeReq &&
$daysLeftUntilChangeReq > 0
)
)
{
$UserKnowsAboutPwdChange = true;
$message = lang('your password is about to expire in %1 days, you may change your password now',round($daysLeftUntilChangeReq));
}
elseif ($passwordAgeBorder > $alpwchange_val && $alpwchange_val > 0)
{
error_log(__METHOD__.' Password of '.$GLOBALS['egw_info']['user']['account_lid'].' ('.$GLOBALS['egw_info']['user']['account_fullname'].') is of old age.'.array2string(array(
'ts'=>$GLOBALS['egw_info']['user']['account_lastpwd_change'],
'date'=>egw_time::to($GLOBALS['egw_info']['user']['account_lastpwd_change']))));
$message = lang('it has been more then %1 days since you changed your password',$GLOBALS['egw_info']['server']['change_pwd_every_x_days']);
}
if ($GLOBALS['egw_info']['user']['apps']['password']) egw::redirect_link('/preferences/password.php',array('message'=>$message));
egw::redirect_link('/index.php',array('menuaction'=>'preferences.uipassword.change','message'=>$message));
}
return true;
}
/**
* fetch the last pwd change for the user
*
* @param string $username username of account to authenticate
* @return mixed false or shadowlastchange*24*3600
*/
function getLastPwdChange($username)
{
if (method_exists($this->backend,'getLastPwdChange')) return $this->backend->getLastPwdChange($username);
return false;
}
/**
* changes account_lastpwd_change in ldap datababse
*
* @param int $account_id account id of user whose passwd should be changed
* @param string $passwd must be cleartext, usually not used, but may be used to authenticate as user to do the change -> ldap
* @param int $lastpwdchange must be a unixtimestamp
* @return boolean true if account_lastpwd_change successful changed, false otherwise
*/
function setLastPwdChange($account_id=0, $passwd=NULL, $lastpwdchange=NULL)
{
if (method_exists($this->backend,'setLastPwdChange')) return $this->backend->setLastPwdChange($account_id, $passwd, $lastpwdchange);
return false;
}
/**
* password authentication against password stored in sql datababse
*
* @param string $username username of account to authenticate
* @param string $passwd corresponding password
* @param string $passwd_type='text' 'text' for cleartext passwords (default)
* @return boolean true if successful authenticated, false otherwise
*/
function authenticate($username, $passwd, $passwd_type='text')
{
return $this->backend->authenticate($username, $passwd, $passwd_type);
}
/**
* changes password in sql datababse
*
* @param string $old_passwd must be cleartext
* @param string $new_passwd must be cleartext
* @param int $account_id account id of user whose passwd should be changed
* @return boolean true if password successful changed, false otherwise
*/
function change_password($old_passwd, $new_passwd, $account_id=0)
{
return $this->backend->change_password($old_passwd, $new_passwd, $account_id);
}
/**
* return a random string of letters [0-9a-zA-Z] of size $size
*
* @param $size int-size of random string to return
*/
static function randomstring($size)
{
static $random_char = array(
'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f',
'g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v',
'w','x','y','z','A','B','C','D','E','F','G','H','I','J','K','L',
'M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'
);
$s = '';
for ($i=0; $i<$size; $i++)
{
$s .= $random_char[mt_rand(1,61)];
}
return $s;
}
/**
* encrypt password
*
* uses the encryption type set in setup and calls the appropriate encryption functions
*
* @param $password password to encrypt
*/
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static function encrypt_password($password,$sql=False)
{
if($sql)
{
return self::encrypt_sql($password);
}
return self::encrypt_ldap($password);
}
/**
* compares an encrypted password
*
* encryption type set in setup and calls the appropriate encryption functions
*
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* @param string $cleartext cleartext password
* @param string $encrypted encrypted password, can have a {hash} prefix, which overrides $type
* @param string $type_i type of encryption
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* @param string $username used as optional key of encryption for md5_hmac
* @param string &$type=null on return detected type of hash
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* @return boolean
*/
static function compare_password($cleartext, $encrypted, $type_in, $username='', &$type=null)
{
// allow to specify the hash type to prefix the hash, to easy migrate passwords from ldap
$type = $type_in;
$saved_enc = $encrypted;
if (preg_match('/^\\{([a-z_5]+)\\}(.+)$/i',$encrypted,$matches))
{
$type = strtolower($matches[1]);
$encrypted = $matches[2];
switch($type) // some hashs are specially "packed" in ldap
{
case 'md5':
$encrypted = implode('',unpack('H*',base64_decode($encrypted)));
break;
case 'plain':
case 'crypt':
// nothing to do
break;
default:
$encrypted = $saved_enc;
break;
}
}
elseif($encrypted[0] == '$')
{
$type = 'crypt';
}
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switch($type)
{
case 'plain':
$ret = $cleartext === $encrypted;
break;
case 'smd5':
$ret = self::smd5_compare($cleartext,$encrypted);
break;
case 'sha':
$ret = self::sha_compare($cleartext,$encrypted);
break;
case 'ssha':
$ret = self::ssha_compare($cleartext,$encrypted);
break;
case 'crypt':
case 'des':
case 'md5_crypt':
case 'blowish_crypt': // was for some time a typo in setup
case 'blowfish_crypt':
case 'ext_crypt':
case 'sha256_crypt':
case 'sha512_crypt':
$ret = self::crypt_compare($cleartext, $encrypted, $type);
break;
case 'md5_hmac':
$ret = self::md5_hmac_compare($cleartext,$encrypted,$username);
break;
default:
$type = 'md5';
// fall through
case 'md5':
$ret = md5($cleartext) === $encrypted;
break;
}
//error_log(__METHOD__."('$cleartext', '$encrypted', '$type_in', '$username') type='$type' returning ".array2string($ret));
return $ret;
}
/**
* Parameters used for crypt: const name, salt prefix, len of random salt, postfix
*
* @var array
*/
static $crypt_params = array( //
'crypt' => array('CRYPT_STD_DES', '', 2, ''),
'ext_crypt' => array('CRYPT_EXT_DES', '_J9..', 4, ''),
'md5_crypt' => array('CRYPT_MD5', '$1$', 8, '$'),
//'old_blowfish_crypt' => array('CRYPT_BLOWFISH', '$2$', 13, ''), // old blowfish hash not in line with php.net docu, but could be in use
'blowfish_crypt' => array('CRYPT_BLOWFISH', '$2a$12$', 22, ''), // $2a$12$ = 2^12 = 4096 rounds
'sha256_crypt' => array('CRYPT_SHA256', '$5$', 16, '$'), // no "round=N$" --> default of 5000 rounds
'sha512_crypt' => array('CRYPT_SHA512', '$6$', 16, '$'), // no "round=N$" --> default of 5000 rounds
);
/**
* compare crypted passwords for authentication whether des,ext_des,md5, or blowfish crypt
*
* @param string $form_val user input value for comparison
* @param string $db_val stored value / hash (from database)
* @param string &$type detected crypt type on return
* @return boolean True on successful comparison
*/
static function crypt_compare($form_val, $db_val, &$type)
{
// detect type of hash by salt part of $db_val
list($first, $dollar, $salt, $salt2) = explode('$', $db_val);
foreach(self::$crypt_params as $type => $params)
{
list(,$prefix, $random, $postfix) = $params;
list(,$d) = explode('$', $prefix);
if ($dollar === $d || !$dollar && ($first[0] === $prefix[0] || $first[0] !== '_' && !$prefix))
{
$len = !$postfix ? strlen($prefix)+$random : strlen($prefix.$salt.$postfix);
// sha(256|512) might contain options, explicit $rounds=N$ prefix in salt
if (($type == 'sha256_crypt' || $type == 'sha512_crypt') && substr($salt, 0, 7) === 'rounds=')
{
$len += strlen($salt2)+1;
}
break;
}
}
$salt = substr($db_val, 0, $len);
$new_hash = crypt($form_val, $salt);
//error_log(__METHOD__."('$form_val', '$db_val') type=$type --> len=$len --> salt='$salt' --> new_hash='$new_hash' returning ".array2string($db_val === $new_hash));
return $db_val === $new_hash;
}
/**
* encrypt password for ldap
*
* uses the encryption type set in setup and calls the appropriate encryption functions
*
* @param $password password to encrypt
* @param $type=null default to $GLOBALS['egw_info']['server']['ldap_encryption_type']
* @return string
*/
static function encrypt_ldap($password, $type=null)
{
if (is_null($type)) $type = $GLOBALS['egw_info']['server']['ldap_encryption_type'];
$salt = '';
switch(strtolower($type))
{
default: // eg. setup >> config never saved
case 'des':
case 'blowish_crypt': // was for some time a typo in setup
$type = $type == 'blowish_crypt' ? 'blowfish_crypt' : 'crypt';
// fall through
case 'crypt':
case 'sha256_crypt':
case 'sha512_crypt':
case 'blowfish_crypt':
case 'md5_crypt':
case 'ext_crypt':
list($const, $prefix, $len, $postfix) = self::$crypt_params[$type];
if(defined($const) && constant($const) == 1)
{
$salt = $prefix.self::randomstring($len).$postfix;
$e_password = '{crypt}'.crypt($password, $salt);
break;
}
self::$error = 'no '.str_replace('_', ' ', $type);
$e_password = false;
break;
case 'md5':
/* New method taken from the openldap-software list as recommended by
* Kervin L. Pierre" <kervin@blueprint-tech.com>
*/
$e_password = '{md5}' . base64_encode(pack("H*",md5($password)));
break;
case 'smd5':
$salt = self::randomstring(16);
$hash = md5($password . $salt, true);
$e_password = '{SMD5}' . base64_encode($hash . $salt);
break;
case 'sha':
$e_password = '{SHA}' . base64_encode(sha1($password,true));
break;
case 'ssha':
$salt = self::randomstring(16);
$hash = sha1($password . $salt, true);
$e_password = '{SSHA}' . base64_encode($hash . $salt);
break;
case 'plain':
// if plain no type is prepended
$e_password = $password;
break;
}
//error_log(__METHOD__."('$password', ".array2string($type).") returning ".array2string($e_password).(self::$error ? ' error='.self::$error : ''));
return $e_password;
}
/**
* Create a password for storage in the accounts table
*
* @param string $password
* @return string hash
*/
static function encrypt_sql($password)
{
/* Grab configured type, or default to md5() (old method) */
$type = @$GLOBALS['egw_info']['server']['sql_encryption_type'] ?
strtolower($GLOBALS['egw_info']['server']['sql_encryption_type']) : 'md5';
switch($type)
{
case 'plain':
// since md5 is the default, type plain must be prepended, for eGroupware to understand
$e_password = '{PLAIN}'.$password;
break;
case 'md5':
/* This is the old standard for password storage in SQL */
$e_password = md5($password);
break;
// all other types are identical to ldap, so no need to doublicate the code here
case 'des':
case 'blowish_crypt': // was for some time a typo in setup
case 'crypt':
case 'sha256_crypt':
case 'sha512_crypt':
case 'blowfish_crypt':
case 'md5_crypt':
case 'ext_crypt':
case 'smd5':
case 'sha':
case 'ssha':
$e_password = self::encrypt_ldap($password, $type);
break;
default:
self::$error = 'no valid encryption available';
$e_password = false;
break;
}
//error_log(__METHOD__."('$password') using '$type' returning ".array2string($e_password).(self::$error ? ' error='.self::$error : ''));
return $e_password;
}
/**
* Checks if a given password is "safe"
*
* @param string $login
* @abstract atm a simple check in length, #digits, #uppercase and #lowercase
* could be made more safe using e.g. pecl library cracklib
* but as pecl dosn't run on any platform and isn't GPL'd
* i haven't implemented it yet
* Windows compatible check is: 7 char lenth, 1 Up, 1 Low, 1 Num and 1 Special
* @author cornelius weiss <egw at von-und-zu-weiss.de>
* @return mixed false if password is considered "safe" or a string $message if "unsafe"
*/
static function crackcheck($passwd,$reqstrength=5)
{
if (!preg_match('/.{'. ($noc=7). ',}/',$passwd))
{
$message[] = lang('Password must have at least %1 characters',$noc). '<br>';
}
else
{
$strength++;
}
if(!preg_match('/(.*\d.*){'. ($non=1). ',}/',$passwd))
{
$message[] = lang('Password must contain at least %1 numbers',$non). '<br>';
}
else
{
$strength++;
}
if(!preg_match('/(.*[[:upper:]].*){'. ($nou=1). ',}/',$passwd))
{
$message[] = lang('Password must contain at least %1 uppercase letters',$nou). '<br>';
}
else
{
$strength++;
}
if(!preg_match('/(.*[[:lower:]].*){'. ($nol=1). ',}/',$passwd))
{
$message[] = lang('Password must contain at least %1 lowercase letters',$nol). '<br>';
}
else
{
$strength++;
}
if(!preg_match('/(.*[\\!"#$%&\'()*+,-.\/:;<=>?@\[\]\^_ {|}~`].*){'. ($nol=1). ',}/',$passwd))
{
$message[] = lang('Password must contain at least %1 special characters',$nol). '<br>';
}
else
{
$strength++;
}
if (count($message)>0 && $reqstrength>$strength)
{
$outmessage = lang('Your Password does not meet the required strength.<br> You must meet %1 criteria. You met only %2 criteria. <br>Your Password failed the following criteria:',$reqstrength,$strength);
$outmessage .= '<br>'.implode(' ',$message);
}
else
{
$outmessage =false;
}
return $outmessage ? $outmessage : false;
}
/**
* compare SMD5-encrypted passwords for authentication
*
* @param string $form_val user input value for comparison
* @param string $db_val stored value (from database)
* @return boolean True on successful comparison
*/
static function smd5_compare($form_val,$db_val)
{
/* Start with the first char after {SMD5} */
$hash = base64_decode(substr($db_val,6));
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/* SMD5 hashes are 16 bytes long */
$orig_hash = cut_bytes($hash, 0, 16); // binary string need to use cut_bytes, not mb_substr(,,'utf-8')!
$salt = cut_bytes($hash, 16);
$new_hash = md5($form_val . $salt,true);
//echo '<br> DB: ' . base64_encode($orig_hash) . '<br>FORM: ' . base64_encode($new_hash);
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return strcmp($orig_hash,$new_hash) == 0;
}
/**
* compare SHA-encrypted passwords for authentication
*
* @param string $form_val user input value for comparison
* @param string $db_val stored value (from database)
* @return boolean True on successful comparison
*/
static function sha_compare($form_val,$db_val)
{
/* Start with the first char after {SHA} */
$hash = base64_decode(substr($db_val,5));
$new_hash = sha1($form_val,true);
//echo '<br> DB: ' . base64_encode($orig_hash) . '<br>FORM: ' . base64_encode($new_hash);
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return strcmp($hash,$new_hash) == 0;
}
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/**
* compare SSHA-encrypted passwords for authentication
*
* @param string $form_val user input value for comparison
* @param string $db_val stored value (from database)
* @return boolean True on successful comparison
*/
static function ssha_compare($form_val,$db_val)
{
/* Start with the first char after {SSHA} */
$hash = base64_decode(substr($db_val, 6));
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// SHA-1 hashes are 160 bits long
$orig_hash = cut_bytes($hash, 0, 20); // binary string need to use cut_bytes, not mb_substr(,,'utf-8')!
$salt = cut_bytes($hash, 20);
$new_hash = sha1($form_val . $salt,true);
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//error_log(__METHOD__."('$form_val', '$db_val') hash='$hash', orig_hash='$orig_hash', salt='$salt', new_hash='$new_hash' returning ".array2string(strcmp($orig_hash,$new_hash) == 0));
return strcmp($orig_hash,$new_hash) == 0;
}
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/**
* compare md5_hmac-encrypted passwords for authentication (see RFC2104)
*
* @param string $form_val user input value for comparison
* @param string $db_val stored value (from database)
* @param string $key key for md5_hmac-encryption (username for imported smf users)
* @return boolean True on successful comparison
*/
static function md5_hmac_compare($form_val,$db_val,$key)
{
$key = str_pad(strlen($key) <= 64 ? $key : pack('H*', md5($key)), 64, chr(0x00));
$md5_hmac = md5(($key ^ str_repeat(chr(0x5c), 64)) . pack('H*', md5(($key ^ str_repeat(chr(0x36), 64)). $form_val)));
return strcmp($md5_hmac,$db_val) == 0;
}
}
/**
* Interface for authentication backend
*/
interface auth_backend
{
/**
* password authentication against password stored in sql datababse
*
* @param string $username username of account to authenticate
* @param string $passwd corresponding password
* @param string $passwd_type='text' 'text' for cleartext passwords (default)
* @return boolean true if successful authenticated, false otherwise
*/
function authenticate($username, $passwd, $passwd_type='text');
/**
* changes password in sql datababse
*
* @param string $old_passwd must be cleartext
* @param string $new_passwd must be cleartext
* @param int $account_id account id of user whose passwd should be changed
* @return boolean true if password successful changed, false otherwise
*/
function change_password($old_passwd, $new_passwd, $account_id=0);
}