BookStack/app/Auth/Access/LdapService.php
2019-03-09 01:08:49 -05:00

388 lines
12 KiB
PHP

<?php namespace BookStack\Auth\Access;
use BookStack\Auth\Access;
use BookStack\Auth\Role;
use BookStack\Auth\User;
use BookStack\Auth\UserRepo;
use BookStack\Exceptions\LdapException;
use Illuminate\Contracts\Auth\Authenticatable;
use Illuminate\Database\Eloquent\Builder;
/**
* Class LdapService
* Handles any app-specific LDAP tasks.
* @package BookStack\Services
*/
class LdapService
{
protected $ldap;
protected $ldapConnection;
protected $config;
protected $userRepo;
protected $enabled;
/**
* LdapService constructor.
* @param Ldap $ldap
* @param \BookStack\Auth\UserRepo $userRepo
*/
public function __construct(Access\Ldap $ldap, UserRepo $userRepo)
{
$this->ldap = $ldap;
$this->config = config('services.ldap');
$this->userRepo = $userRepo;
$this->enabled = config('auth.method') === 'ldap';
}
/**
* Check if groups should be synced.
* @return bool
*/
public function shouldSyncGroups()
{
return $this->enabled && $this->config['user_to_groups'] !== false;
}
/**
* Search for attributes for a specific user on the ldap
* @param string $userName
* @param array $attributes
* @return null|array
* @throws LdapException
*/
private function getUserWithAttributes($userName, $attributes)
{
$ldapConnection = $this->getConnection();
$this->bindSystemUser($ldapConnection);
// Find user
$userFilter = $this->buildFilter($this->config['user_filter'], ['user' => $userName]);
$baseDn = $this->config['base_dn'];
$followReferrals = $this->config['follow_referrals'] ? 1 : 0;
$this->ldap->setOption($ldapConnection, LDAP_OPT_REFERRALS, $followReferrals);
$users = $this->ldap->searchAndGetEntries($ldapConnection, $baseDn, $userFilter, $attributes);
if ($users['count'] === 0) {
return null;
}
return $users[0];
}
/**
* Get the details of a user from LDAP using the given username.
* User found via configurable user filter.
* @param $userName
* @return array|null
* @throws LdapException
*/
public function getUserDetails($userName)
{
$emailAttr = $this->config['email_attribute'];
$displayNameAttr = $this->config['display_name_attribute'];
$user = $this->getUserWithAttributes($userName, ['cn', 'uid', 'dn', $emailAttr, $displayNameAttr]);
if ($user === null) {
return null;
}
return [
'uid' => (isset($user['uid'])) ? $user['uid'][0] : $user['dn'],
'name' => (isset($user[$displayNameAttr])) ? (is_array($user[$displayNameAttr]) ? $user[$displayNameAttr][0] : $user[$displayNameAttr]) : $user['cn'][0],
'dn' => $user['dn'],
'email' => (isset($user[$emailAttr])) ? (is_array($user[$emailAttr]) ? $user[$emailAttr][0] : $user[$emailAttr]) : null
];
}
/**
* @param Authenticatable $user
* @param string $username
* @param string $password
* @return bool
* @throws LdapException
*/
public function validateUserCredentials(Authenticatable $user, $username, $password)
{
$ldapUser = $this->getUserDetails($username);
if ($ldapUser === null) {
return false;
}
if ($ldapUser['uid'] !== $user->external_auth_id) {
return false;
}
$ldapConnection = $this->getConnection();
try {
$ldapBind = $this->ldap->bind($ldapConnection, $ldapUser['dn'], $password);
} catch (\ErrorException $e) {
$ldapBind = false;
}
return $ldapBind;
}
/**
* Bind the system user to the LDAP connection using the given credentials
* otherwise anonymous access is attempted.
* @param $connection
* @throws LdapException
*/
protected function bindSystemUser($connection)
{
$ldapDn = $this->config['dn'];
$ldapPass = $this->config['pass'];
$isAnonymous = ($ldapDn === false || $ldapPass === false);
if ($isAnonymous) {
$ldapBind = $this->ldap->bind($connection);
} else {
$ldapBind = $this->ldap->bind($connection, $ldapDn, $ldapPass);
}
if (!$ldapBind) {
throw new LdapException(($isAnonymous ? trans('errors.ldap_fail_anonymous') : trans('errors.ldap_fail_authed')));
}
}
/**
* Get the connection to the LDAP server.
* Creates a new connection if one does not exist.
* @return resource
* @throws LdapException
*/
protected function getConnection()
{
if ($this->ldapConnection !== null) {
return $this->ldapConnection;
}
// Check LDAP extension in installed
if (!function_exists('ldap_connect') && config('app.env') !== 'testing') {
throw new LdapException(trans('errors.ldap_extension_not_installed'));
}
// Get port from server string and protocol if specified.
$ldapServer = explode(':', $this->config['server']);
$hasProtocol = preg_match('/^ldaps{0,1}\:\/\//', $this->config['server']) === 1;
if (!$hasProtocol) {
array_unshift($ldapServer, '');
}
$hostName = $ldapServer[0] . ($hasProtocol?':':'') . $ldapServer[1];
$defaultPort = $ldapServer[0] === 'ldaps' ? 636 : 389;
/*
* Check if TLS_INSECURE is set. The handle is set to NULL due to the nature of
* the LDAP_OPT_X_TLS_REQUIRE_CERT option. It can only be set globally and not
* per handle.
*/
if ($this->config['tls_insecure']) {
$this->ldap->setOption(null, LDAP_OPT_X_TLS_REQUIRE_CERT, LDAP_OPT_X_TLS_NEVER);
}
$ldapConnection = $this->ldap->connect($hostName, count($ldapServer) > 2 ? intval($ldapServer[2]) : $defaultPort);
if ($ldapConnection === false) {
throw new LdapException(trans('errors.ldap_cannot_connect'));
}
// Set any required options
if ($this->config['version']) {
$this->ldap->setVersion($ldapConnection, $this->config['version']);
}
$this->ldapConnection = $ldapConnection;
return $this->ldapConnection;
}
/**
* Build a filter string by injecting common variables.
* @param string $filterString
* @param array $attrs
* @return string
*/
protected function buildFilter($filterString, array $attrs)
{
$newAttrs = [];
foreach ($attrs as $key => $attrText) {
$newKey = '${' . $key . '}';
$newAttrs[$newKey] = $this->ldap->escape($attrText);
}
return strtr($filterString, $newAttrs);
}
/**
* Get the groups a user is a part of on ldap
* @param string $userName
* @return array
* @throws LdapException
*/
public function getUserGroups($userName)
{
$groupsAttr = $this->config['group_attribute'];
$user = $this->getUserWithAttributes($userName, [$groupsAttr]);
if ($user === null) {
return [];
}
$userGroups = $this->groupFilter($user);
$userGroups = $this->getGroupsRecursive($userGroups, []);
return $userGroups;
}
/**
* Get the parent groups of an array of groups
* @param array $groupsArray
* @param array $checked
* @return array
* @throws LdapException
*/
private function getGroupsRecursive($groupsArray, $checked)
{
$groups_to_add = [];
foreach ($groupsArray as $groupName) {
if (in_array($groupName, $checked)) {
continue;
}
$groupsToAdd = $this->getGroupGroups($groupName);
$groups_to_add = array_merge($groups_to_add, $groupsToAdd);
$checked[] = $groupName;
}
$groupsArray = array_unique(array_merge($groupsArray, $groups_to_add), SORT_REGULAR);
if (!empty($groups_to_add)) {
return $this->getGroupsRecursive($groupsArray, $checked);
} else {
return $groupsArray;
}
}
/**
* Get the parent groups of a single group
* @param string $groupName
* @return array
* @throws LdapException
*/
private function getGroupGroups($groupName)
{
$ldapConnection = $this->getConnection();
$this->bindSystemUser($ldapConnection);
$followReferrals = $this->config['follow_referrals'] ? 1 : 0;
$this->ldap->setOption($ldapConnection, LDAP_OPT_REFERRALS, $followReferrals);
$baseDn = $this->config['base_dn'];
$groupsAttr = strtolower($this->config['group_attribute']);
$groupFilter = 'CN=' . $this->ldap->escape($groupName);
$groups = $this->ldap->searchAndGetEntries($ldapConnection, $baseDn, $groupFilter, [$groupsAttr]);
if ($groups['count'] === 0) {
return [];
}
$groupGroups = $this->groupFilter($groups[0]);
return $groupGroups;
}
/**
* Filter out LDAP CN and DN language in a ldap search return
* Gets the base CN (common name) of the string
* @param array $userGroupSearchResponse
* @return array
*/
protected function groupFilter(array $userGroupSearchResponse)
{
$groupsAttr = strtolower($this->config['group_attribute']);
$ldapGroups = [];
$count = 0;
if (isset($userGroupSearchResponse[$groupsAttr]['count'])) {
$count = (int) $userGroupSearchResponse[$groupsAttr]['count'];
}
for ($i=0; $i<$count; $i++) {
$dnComponents = $this->ldap->explodeDn($userGroupSearchResponse[$groupsAttr][$i], 1);
if (!in_array($dnComponents[0], $ldapGroups)) {
$ldapGroups[] = $dnComponents[0];
}
}
return $ldapGroups;
}
/**
* Sync the LDAP groups to the user roles for the current user
* @param \BookStack\Auth\User $user
* @param string $username
* @throws LdapException
*/
public function syncGroups(User $user, string $username)
{
$userLdapGroups = $this->getUserGroups($username);
// Get the ids for the roles from the names
$ldapGroupsAsRoles = $this->matchLdapGroupsToSystemsRoles($userLdapGroups);
// Sync groups
if ($this->config['remove_from_groups']) {
$user->roles()->sync($ldapGroupsAsRoles);
$this->userRepo->attachDefaultRole($user);
} else {
$user->roles()->syncWithoutDetaching($ldapGroupsAsRoles);
}
}
/**
* Match an array of group names from LDAP to BookStack system roles.
* Formats LDAP group names to be lower-case and hyphenated.
* @param array $groupNames
* @return \Illuminate\Support\Collection
*/
protected function matchLdapGroupsToSystemsRoles(array $groupNames)
{
foreach ($groupNames as $i => $groupName) {
$groupNames[$i] = str_replace(' ', '-', trim(strtolower($groupName)));
}
$roles = Role::query()->where(function (Builder $query) use ($groupNames) {
$query->whereIn('name', $groupNames);
foreach ($groupNames as $groupName) {
$query->orWhere('external_auth_id', 'LIKE', '%' . $groupName . '%');
}
})->get();
$matchedRoles = $roles->filter(function (Role $role) use ($groupNames) {
return $this->roleMatchesGroupNames($role, $groupNames);
});
return $matchedRoles->pluck('id');
}
/**
* Check a role against an array of group names to see if it matches.
* Checked against role 'external_auth_id' if set otherwise the name of the role.
* @param \BookStack\Auth\Role $role
* @param array $groupNames
* @return bool
*/
protected function roleMatchesGroupNames(Role $role, array $groupNames)
{
if ($role->external_auth_id) {
$externalAuthIds = explode(',', strtolower($role->external_auth_id));
foreach ($externalAuthIds as $externalAuthId) {
if (in_array(trim($externalAuthId), $groupNames)) {
return true;
}
}
return false;
}
$roleName = str_replace(' ', '-', trim(strtolower($role->display_name)));
return in_array($roleName, $groupNames);
}
}