Added support for LDAP.

Core/Frameworks/Baikal/Core/LDAP.php

@@ -0,0 +1,298 @@
+<?php
+
+namespace Baikal\Core;
+
+use Exception;
+
+#################################################################
+#  Copyright notice
+#
+#  (c) 2022 Aisha Tammy <aisha@bsd.ac>
+#  (c) 2022 El-Virus <elvirus@ilsrv.com>
+#  All rights reserved
+#
+#  http://sabre.io/baikal
+#
+#  This script is part of the Baïkal Server project. The Baïkal
+#  Server project is free software; you can redistribute it
+#  and/or modify it under the terms of the GNU General Public
+#  License as published by the Free Software Foundation; either
+#  version 2 of the License, or (at your option) any later version.
+#
+#  The GNU General Public License can be found at
+#  http://www.gnu.org/copyleft/gpl.html.
+#
+#  This script is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  This copyright notice MUST APPEAR in all copies of the script!
+#################################################################
+
+/**
+ * This is an authentication backend that uses ldap.
+ */
+class LDAP extends \Sabre\DAV\Auth\Backend\AbstractBasic {
+    /**
+     * Reference to PDO connection.
+     *
+     * @var PDO
+     */
+    protected $pdo;
+
+    /**
+     * PDO table name we'll be using.
+     *
+     * @var string
+     */
+    protected $table_name;
+
+    /**
+     * LDAP Config.
+     * LDAP Config Struct.
+     *
+     * @var \Baikal\Model\Structs\LDAPConfig
+     */
+    protected $ldap_config;
+
+    /**
+     * Replaces patterns for their assigned value using the
+     * given username, using cyrus-sasl style replacements.
+     *
+     * %u   - gets replaced by full username
+     * %U   - gets replaced by user part when the
+     *        username is an email address
+     * %d   - gets replaced by domain part when the
+     *        username is an email address
+     * %%   - gets replaced by %
+     * %1-9 - gets replaced by parts of the the domain
+     *        split by '.' in reverse order
+     *
+     * full example for jane.doe@mail.example.org:
+     *        %u = jane.doe@mail.example.org
+     *        %U = jane.doe
+     *        %d = mail.example.org
+     *        %1 = org
+     *        %2 = example
+     *        %3 = mail
+     *
+     * @param string $line
+     * @param string $username
+     *
+     * @return string
+     */
+    protected function patternReplace($line, $username) {
+        $user_split = [$username];
+        $user = $username;
+        $domain = '';
+        try {
+            $user_split = explode('@', $username, 2);
+            $user = $user_split[0];
+            if (2 == count($user_split)) {
+                $domain = $user_split[1];
+            }
+        } catch (Exception $ignored) {
+        }
+        $domain_split = [];
+        try {
+            $domain_split = array_reverse(explode('.', $domain));
+        } catch (Exception $ignored) {
+            $domain_split = [];
+        }
+
+        $parsed_line = '';
+        for ($i = 0; $i < strlen($line); ++$i) {
+            if ('%' == $line[$i]) {
+                ++$i;
+                $next_char = $line[$i];
+                if ('u' == $next_char) {
+                    $parsed_line .= $username;
+                } elseif ('U' == $next_char) {
+                    $parsed_line .= $user;
+                } elseif ('d' == $next_char) {
+                    $parsed_line .= $domain;
+                } elseif ('%' == $next_char) {
+                    $parsed_line .= '%';
+                } else {
+                    for ($j = 1; $j <= count($domain_split) && $j <= 9; ++$j) {
+                        if ($next_char == '' . $j) {
+                            $parsed_line .= $domain_split[$j - 1];
+                        }
+                    }
+                }
+            } else {
+                $parsed_line .= $line[$i];
+            }
+        }
+
+        return $parsed_line;
+    }
+
+    /**
+     * Checks if a user can bind with a password.
+     * If an error is produced, it will be logged.
+     *
+     * @param \LDAP\Connection &$conn
+     * @param string $dn
+     * @param string $password
+     *
+     * @return bool
+     */
+    protected function doesBind(&$conn, $dn, $password) {
+        try {
+            $bind = ldap_bind($conn, $dn, $password);
+            if ($bind) {
+                return true;
+            }
+        } catch (\ErrorException $e) {
+            error_log($e->getMessage());
+            error_log(ldap_error($conn));
+        }
+
+        return false;
+    }
+
+    /**
+     * Creates the backend object.
+     *
+     * @param \PD0 $pdo
+     * @param string $table_name
+     * @param \Baikal\Model\Structs\LDAPConfig $ldap_config
+     */
+    public function __construct(\PDO $pdo, $table_name, $ldap_config) {
+        $this->pdo          = $pdo;
+        $this->table_name   = $table_name;
+        $this->ldap_config  = $ldap_config;
+    }
+
+    /**
+     * Connects to an LDAP server and tries to authenticate.
+     *
+     * @param string $username
+     * @param string $password
+     *
+     * @return bool
+     */
+    protected function ldapOpen($username, $password) {
+        $conn = ldap_connect($this->ldap_config->ldap_uri);
+        if (!$conn) {
+            return false;
+        }
+        if (!ldap_set_option($conn, LDAP_OPT_PROTOCOL_VERSION, 3)) {
+            return false;
+        }
+
+        $success = false;
+
+        if ($this->ldap_config->ldap_mode == 'DN') {
+            $dn = $this->patternReplace($this->ldap_config->ldap_dn, $username);
+
+            $success = $this->doesBind($conn, $dn, $password);
+        } elseif ($this->ldap_config->ldap_mode == 'Attribute' || $this->ldap_config->ldap_mode == 'Group') {
+            try {
+                if (!$this->doesBind($conn, $this->ldap_config->ldap_bind_dn, $this->ldap_config->ldap_bind_password)) {
+                    return false;
+                }
+
+                $attribute = $this->ldap_config->ldap_search_attribute;
+                $attribute = $this->patternReplace($attribute, $username);
+
+                $result = ldap_get_entries($conn, ldap_search($conn, $this->ldap_config->ldap_search_base, '(' . $attribute . ')',
+                    [explode('=', $attribute, 2)[0]], 0, 1, 0, LDAP_DEREF_ALWAYS, []))[0];
+
+                $dn = $result["dn"];
+
+                if ($this->ldap_config->ldap_mode == 'Group') {
+                    $inGroup = false;
+                    $members = ldap_get_entries($conn, ldap_read($conn, $this->ldap_config->ldap_group, '(objectClass=*)',
+                        ['member', 'uniqueMember'], 0, 0, 0, LDAP_DEREF_NEVER, []))[0];
+                    if (isset($members["member"])) {
+                        foreach ($members["member"] as $member) {
+                            if ($member == $result["dn"]) {
+                                $inGroup = true;
+                                break;
+                            }
+                        }
+                    }
+                    if (isset($members["uniqueMember"])) {
+                        foreach ($members["uniqueMember"] as $member) {
+                            if ($member == $result["dn"]) {
+                                $inGroup = false;
+                                break;
+                            }
+                        }
+                    }
+                    if (!$inGroup) {
+                        return false;
+                    }
+                }
+
+                $success = $this->doesBind($conn, $dn, $password);
+            } catch (\ErrorException $e) {
+                error_log($e->getMessage());
+                error_log(ldap_error($conn));
+            }
+        } elseif ($this->ldap_config->ldap_mode == 'Filter') {
+            try {
+                if (!$this->doesBind($conn, $this->ldap_config->ldap_bind_dn, $this->ldap_config->ldap_bind_password)) {
+                    return false;
+                }
+
+                $filter = $this->ldap_config->ldap_search_filter;
+                $filter = $this->patternReplace($filter, $username);
+
+                $result = ldap_get_entries($conn, ldap_search($conn, $this->ldap_config->ldap_search_base, $filter, [], 0, 1, 0, LDAP_DEREF_ALWAYS, []))[0];
+
+                $dn = $result["dn"];
+                $success = $this->doesBind($conn, $dn, $password);
+            } catch (\ErrorException $e) {
+                error_log($e->getMessage());
+                error_log(ldap_error($conn));
+            }
+        } else {
+            error_log('Unknown LDAP authentication mode');
+        }
+
+        if ($success) {
+            $stmt = $this->pdo->prepare('SELECT username, digesta1 FROM ' . $this->table_name . ' WHERE username = ?');
+            $stmt->execute([$username]);
+            $result = $stmt->fetchAll();
+
+            if (empty($result)) {
+                $search_results = ldap_read($conn, $dn, '(objectclass=*)', [$this->ldap_config->ldap_cn, $this->ldap_config->ldap_mail]);
+                $entry = ldap_get_entries($conn, $search_results);
+                $user_displayname = $username;
+                $user_email = 'unset-email';
+                if (!empty($entry[0][$this->ldap_config->ldap_cn])) {
+                    $user_displayname = $entry[0][$this->ldap_config->ldap_cn][0];
+                }
+                if (!empty($entry[0][$this->ldap_config->ldap_mail])) {
+                    $user_email = $entry[0][$this->ldap_config->ldap_mail][0];
+                }
+
+                $user = new \Baikal\Model\User();
+                $user->set('username', $username);
+                $user->set('displayname', $user_displayname);
+                $user->set('email', $user_email);
+                $user->persist();
+            }
+        }
+
+        ldap_close($conn);
+
+        return $success;
+    }
+
+    /**
+     * Validates a username and password by trying to authenticate against LDAP.
+     *
+     * @param string $username
+     * @param string $password
+     *
+     * @return bool
+     */
+    protected function validateUserPass($username, $password) {
+        return $this->ldapOpen($username, $password);
+    }
+}

Core/Frameworks/Baikal/Core/Server.php

@@ -135,6 +135,20 @@ protected function initServer() {
             $authBackend = new \Baikal\Core\PDOBasicAuth($this->pdo, $this->authRealm);
         } elseif ($this->authType === 'Apache') {
             $authBackend = new \Sabre\DAV\Auth\Backend\Apache();
+        } elseif ($this->authType === 'LDAP') {
+            $LDAPConfig = new \Baikal\Model\Structs\LDAPConfig();
+            $LDAPConfig->ldap_mode              = $config['system']['ldap_mode'];
+            $LDAPConfig->ldap_uri               = $config['system']['ldap_uri'];
+            $LDAPConfig->ldap_bind_dn           = $config['system']['ldap_bind_dn'];
+            $LDAPConfig->ldap_bind_password     = $config['system']['ldap_bind_password'];
+            $LDAPConfig->ldap_dn                = $config['system']['ldap_dn'];
+            $LDAPConfig->ldap_cn                = $config['system']['ldap_cn'];
+            $LDAPConfig->ldap_mail              = $config['system']['ldap_mail'];
+            $LDAPConfig->ldap_search_base       = $config['system']['ldap_search_base'];
+            $LDAPConfig->ldap_search_attribute  = $config['system']['ldap_search_attribute'];
+            $LDAPConfig->ldap_search_filter     = $config['system']['ldap_search_filter'];
+            $LDAPConfig->ldap_group             = $config['system']['ldap_group'];
+            $authBackend = new \Baikal\Core\LDAP($this->pdo, 'users', $LDAPConfig);
         } else {
             $authBackend = new \Sabre\DAV\Auth\Backend\PDO($this->pdo);
             $authBackend->setRealm($this->authRealm);