Files
librenms-librenms/html/includes/authentication/active_directory.inc.php
Tony Murray 1ea7af424b feature: bind user for active_directory auth (#6255)
* feature: bind user for active_directory auth
Optional, allows the use of "remember me", API, and alerting.

* missing global (but still may not be working)

* always return a value from reauthenticate()

* Make sure the ldapbind credentials are correct on reauth.
Do not send output if they are incorrect (use d_echo) this breaks ajax calls, etc.
Add scripts/auth_test.php, to make it easier to debug authentication.

* Refine auth_test.php a bit more
A few small cleanups in other places of the auth

* Add auth_test.php to docs
Some more improvements in the auth_test.php output.

* Update Authentication.md
2017-03-29 08:22:02 -05:00

468 lines
12 KiB
PHP

<?php
use Phpass\PasswordHash;
// easier to rewrite for Active Directory than to bash it into existing LDAP implementation
// disable certificate checking before connect if required
if (isset($config['auth_ad_check_certificates']) &&
!$config['auth_ad_check_certificates']) {
putenv('LDAPTLS_REQCERT=never');
};
if (isset($config['auth_ad_debug']) && $config['auth_ad_debug']) {
ldap_set_option(null, LDAP_OPT_DEBUG_LEVEL, 7);
}
$ldap_connection = @ldap_connect($config['auth_ad_url']);
// disable referrals and force ldap version to 3
ldap_set_option($ldap_connection, LDAP_OPT_REFERRALS, 0);
ldap_set_option($ldap_connection, LDAP_OPT_PROTOCOL_VERSION, 3);
// Bind to AD
if (!ad_bind($ldap_connection)) {
d_echo(ldap_error($ldap_connection) . PHP_EOL);
}
function authenticate($username, $password)
{
global $config, $ldap_connection, $auth_error;
if ($ldap_connection) {
// bind with sAMAccountName instead of full LDAP DN
if ($username && $password && ldap_bind($ldap_connection, "{$username}@{$config['auth_ad_domain']}", $password)) {
// group membership in one of the configured groups is required
if (isset($config['auth_ad_require_groupmembership']) &&
$config['auth_ad_require_groupmembership']) {
$search = ldap_search(
$ldap_connection,
$config['auth_ad_base_dn'],
get_auth_ad_user_filter($username),
array('memberOf')
);
$entries = ldap_get_entries($ldap_connection, $search);
unset($entries[0]['memberof']['count']); //remove the annoying count
foreach ($entries[0]['memberof'] as $entry) {
$group_cn = get_cn($entry);
if (isset($config['auth_ad_groups'][$group_cn]['level'])) {
// user is in one of the defined groups
adduser($username);
return 1;
}
}
if (isset($config['auth_ad_debug']) && $config['auth_ad_debug']) {
if ($entries['count'] == 0) {
$auth_error = 'No groups found for user, check base dn';
} else {
$auth_error = 'User is not in one of the required groups';
}
} else {
$auth_error = 'Invalid credentials';
}
return 0;
} else {
// group membership is not required and user is valid
adduser($username);
return 1;
}
}
}
if (!isset($password) || $password == '') {
$auth_error = "A password is required";
} elseif (isset($config['auth_ad_debug']) && $config['auth_ad_debug']) {
ldap_get_option($ldap_connection, LDAP_OPT_DIAGNOSTIC_MESSAGE, $extended_error);
$auth_error = ldap_error($ldap_connection).'<br />'.$extended_error;
} else {
$auth_error = ldap_error($ldap_connection);
}
return 0;
}
function reauthenticate($sess_id, $token)
{
global $ldap_connection;
if (ad_bind($ldap_connection, false)) {
$sess_id = clean($sess_id);
$token = clean($token);
list($username, $hash) = explode('|', $token);
if (!user_exists($username)) {
d_echo("$username is not a valid AD user\n");
return 0;
}
$session = dbFetchRow(
"SELECT * FROM `session` WHERE `session_username`=? AND session_value=?",
array($username, $sess_id),
true
);
$hasher = new PasswordHash(8, false);
if ($hasher->CheckPassword($username . $session['session_token'], $hash)) {
$_SESSION['username'] = $username;
return 1;
} else {
d_echo("Reauthenticate token check failed\n");
return 0;
}
}
return 0;
}
function passwordscanchange()
{
// not supported so return 0
return 0;
}
function changepassword()
{
// not supported so return 0
return 0;
}
function auth_usermanagement()
{
// not supported so return 0
return 0;
}
function adduser($username, $level = 0, $email = '', $realname = '', $can_modify_passwd = 0, $description = '', $twofactor = 0)
{
// not supported so return 0
return 0;
}
function user_exists_in_db($username)
{
$return = dbFetchCell('SELECT COUNT(*) FROM users WHERE username = ?', array($username), true);
return $return;
}
function user_exists($username)
{
global $config, $ldap_connection;
$search = ldap_search(
$ldap_connection,
$config['auth_ad_base_dn'],
get_auth_ad_user_filter($username),
array('samaccountname')
);
$entries = ldap_get_entries($ldap_connection, $search);
if ($entries['count']) {
return 1;
}
return 0;
}
function get_userlevel($username)
{
global $config, $ldap_connection;
$userlevel = 0;
if (isset($config['auth_ad_require_groupmembership']) && $config['auth_ad_require_groupmembership'] == 0) {
if (isset($config['auth_ad_global_read']) && $config['auth_ad_global_read'] === 1) {
$userlevel = 5;
}
}
// Find all defined groups $username is in
$search = ldap_search(
$ldap_connection,
$config['auth_ad_base_dn'],
get_auth_ad_user_filter($username),
array('memberOf')
);
$entries = ldap_get_entries($ldap_connection, $search);
unset($entries[0]['memberof']['count']);
// Loop the list and find the highest level
foreach ($entries[0]['memberof'] as $entry) {
$group_cn = get_cn($entry);
if (isset($config['auth_ad_groups'][$group_cn]['level']) &&
$config['auth_ad_groups'][$group_cn]['level'] > $userlevel) {
$userlevel = $config['auth_ad_groups'][$group_cn]['level'];
}
}
return $userlevel;
}
function get_userid($username)
{
global $config, $ldap_connection;
$attributes = array('objectsid');
$search = ldap_search(
$ldap_connection,
$config['auth_ad_base_dn'],
get_auth_ad_user_filter($username),
$attributes
);
$entries = ldap_get_entries($ldap_connection, $search);
if ($entries['count']) {
return get_userid_from_sid(sid_from_ldap($entries[0]['objectsid'][0]));
}
return -1;
}
function get_domain_sid()
{
global $config, $ldap_connection;
$search = ldap_read(
$ldap_connection,
$config['auth_ad_base_dn'],
'(objectClass=*)',
array('objectsid')
);
$entry = ldap_get_entries($ldap_connection, $search);
return substr(sid_from_ldap($entry[0]['objectsid'][0]), 0, 41);
}
function get_user($user_id)
{
global $config, $ldap_connection;
$domain_sid = get_domain_sid();
$search_filter = "(&(objectcategory=person)(objectclass=user)(objectsid=$domain_sid-$user_id))";
$attributes = array('samaccountname', 'displayname', 'objectsid', 'mail');
$search = ldap_search($ldap_connection, $config['auth_ad_base_dn'], $search_filter, $attributes);
$entry = ldap_get_entries($ldap_connection, $search);
if (isset($entry[0]['samaccountname'][0])) {
return user_from_ad($entry[0]);
}
return array();
}
function deluser($userid)
{
dbDelete('bill_perms', '`user_id` = ?', array($userid));
dbDelete('devices_perms', '`user_id` = ?', array($userid));
dbDelete('ports_perms', '`user_id` = ?', array($userid));
dbDelete('users_prefs', '`user_id` = ?', array($userid));
return 0;
}
function get_userlist()
{
global $config, $ldap_connection;
$userlist = array();
$ldap_groups = get_group_list();
foreach ($ldap_groups as $ldap_group) {
$search_filter = "(memberOf=$ldap_group)";
if ($config['auth_ad_user_filter']) {
$search_filter = "(&{$config['auth_ad_user_filter']}$search_filter)";
}
$attributes = array('samaccountname', 'displayname', 'objectsid', 'mail');
$search = ldap_search($ldap_connection, $config['auth_ad_base_dn'], $search_filter, $attributes);
$results = ldap_get_entries($ldap_connection, $search);
foreach ($results as $result) {
if (isset($result['samaccountname'][0])) {
$userlist[$result['samaccountname'][0]] = user_from_ad($result);
}
}
}
return array_values($userlist);
}
/**
* Generate a user array from an AD LDAP entry
* Must have the attributes: objectsid, samaccountname, displayname, mail
* @internal
*
* @param $entry
* @return array
*/
function user_from_ad($entry)
{
return array(
'user_id' => get_userid_from_sid(sid_from_ldap($entry['objectsid'][0])),
'username' => $entry['samaccountname'][0],
'realname' => $entry['displayname'][0],
'email' => $entry['mail'][0],
'descr' => '',
'level' => get_userlevel($entry['samaccountname'][0]),
'can_modify_passwd' => 0,
'twofactor' => 0,
// 'dashboard' => 'broken!',
);
}
function can_update_users()
{
// not supported so return 0
return 0;
}
function update_user($user_id, $realname, $level, $can_modify_passwd, $email)
{
// not supported so return 0
return 0;
}
function get_email($username)
{
global $config, $ldap_connection;
$attributes = array('mail');
$search = ldap_search(
$ldap_connection,
$config['auth_ad_base_dn'],
get_auth_ad_user_filter($username),
$attributes
);
$result = ldap_get_entries($ldap_connection, $search);
unset($result[0]['mail']['count']);
return current($result[0]['mail']);
}
function get_fullname($username)
{
global $config, $ldap_connection;
$attributes = array('name');
$result = ldap_search(
$ldap_connection,
$config['auth_ad_base_dn'],
get_auth_ad_user_filter($username),
$attributes
);
$entries = ldap_get_entries($ldap_connection, $result);
if ($entries['count'] > 0) {
$membername = $entries[0]['name'][0];
} else {
$membername = $username;
}
return $membername;
}
function get_group_list()
{
global $config;
$ldap_groups = array();
// show all Active Directory Users by default
$default_group = 'Users';
if (isset($config['auth_ad_group'])) {
if ($config['auth_ad_group'] !== $default_group) {
$ldap_groups[] = $config['auth_ad_group'];
}
}
if (!isset($config['auth_ad_groups']) && !isset($config['auth_ad_group'])) {
$ldap_groups[] = get_dn($default_group);
}
foreach ($config['auth_ad_groups'] as $key => $value) {
$ldap_groups[] = get_dn($key);
}
return $ldap_groups;
}
function get_dn($samaccountname)
{
global $config, $ldap_connection;
$attributes = array('dn');
$result = ldap_search(
$ldap_connection,
$config['auth_ad_base_dn'],
get_auth_ad_group_filter($samaccountname),
$attributes
);
$entries = ldap_get_entries($ldap_connection, $result);
if ($entries['count'] > 0) {
return $entries[0]['dn'];
} else {
return '';
}
}
function get_cn($dn)
{
$dn = str_replace('\\,', '~C0mmA~', $dn);
preg_match('/[^,]*/', $dn, $matches, PREG_OFFSET_CAPTURE, 3);
return str_replace('~C0mmA~', ',', $matches[0][0]);
}
function get_userid_from_sid($sid)
{
return preg_replace('/.*-(\d+)$/', '$1', $sid);
}
function sid_from_ldap($sid)
{
$sidUnpacked = unpack('H*hex', $sid);
$sidHex = array_shift($sidUnpacked);
$subAuths = unpack('H2/H2/n/N/V*', $sid);
$revLevel = hexdec(substr($sidHex, 0, 2));
$authIdent = hexdec(substr($sidHex, 4, 12));
return 'S-'.$revLevel.'-'.$authIdent.'-'.implode('-', $subAuths);
}
/**
* Bind to AD with the bind user if available, otherwise anonymous bind
* @internal
*
* @param resource $connection the ldap connection resource
* @param bool $allow_anonymous attempt anonymous bind if bind user isn't available
* @return bool success or failure
*/
function ad_bind($connection, $allow_anonymous = true)
{
global $config;
if (isset($config['auth_ad_binduser']) && isset($config['auth_ad_bindpassword'])) {
// With specified bind user
return ldap_bind(
$connection,
"${config['auth_ad_binduser']}@${config['auth_ad_domain']}",
"${config['auth_ad_bindpassword']}"
);
}
if ($allow_anonymous) {
// Anonymous
return ldap_bind($connection);
}
return false;
}