complete password fetching on registration; add Requirements section

Fix broken links to mxisd docs

.gitignore

@@ -0,0 +1,2 @@
+config.php
+db_file.sqlite

MatrixConnection.php

@@ -0,0 +1,178 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+class MatrixConnection {
+
+    private $hs;
+    private $at;
+
+    function __construct($homeserver, $access_token) {
+        $this->hs = $homeserver;
+        $this->at = $access_token;
+    }
+
+    function send($room_id, $message) {
+        if (!$this->at) {
+            error_log("No access token defined");
+            return false;
+        }
+
+        $send_message = NULL;
+        if (!$message) {
+            error_log("no message to send");
+            return false;
+        } elseif (is_array($message)) {
+            $send_message = $message;
+        } elseif ($message instanceof MatrixMessage) {
+            $send_message = $message->get_object();
+        } else {
+            error_log("message is of not valid type\n");
+            return false;
+        }
+
+        $url = "https://" . $this->hs . "/_matrix/client/r0/rooms/"
+                . urlencode($room_id) . "/send/m.room.message?access_token=" . $this->at;
+        $handle = curl_init($url);
+        curl_setopt($handle, CURLOPT_RETURNTRANSFER, true);
+        curl_setopt($handle, CURLOPT_CONNECTTIMEOUT, 5);
+        curl_setopt($handle, CURLOPT_TIMEOUT, 60);
+        curl_setopt($handle, CURLOPT_POSTFIELDS, json_encode($send_message));
+        curl_setopt($handle, CURLOPT_HTTPHEADER, array("Content-Type: application/json"));
+
+        $response = $this->exec_curl_request($handle);
+        return isset($response["event_id"]);
+    }
+
+    function send_msg($room_id, $message) {
+        return $this->send($room_id, array(
+                    "msgtype" => "m.notice",
+                    "body" => $message
+                        )
+        );
+    }
+
+    function hasUser($username) {
+        if (!$username) {
+            throw new Exception("no user given to lookup");
+        }
+
+        $url = "https://" . $this->hs . "/_matrix/client/r0/profile/@" . $username . ":" . $this->hs;
+        $handle = curl_init($url);
+        curl_setopt($handle, CURLOPT_RETURNTRANSFER, true);
+        curl_setopt($handle, CURLOPT_CONNECTTIMEOUT, 5);
+        curl_setopt($handle, CURLOPT_TIMEOUT, 60);
+        curl_setopt($handle, CURLOPT_HTTPHEADER, array("Content-Type: application/json"));
+
+        $res = $this->exec_curl_request($handle);
+        return !(isset($res["errcode"]) && $res["errcode"] == "M_UNKNOWN");
+    }
+
+    function register($username, $password, $shared_secret) {
+        if (!$username) {
+            error_log("no username provided");
+        }
+        if (!$password) {
+            error_log("no message to send");
+        }
+
+        $mac = hash_hmac('sha1', $username, $shared_secret);
+
+        $data = array(
+            "username" => $username,
+            "password" => $password,
+            "mac" => $mac,
+        );
+        $url = "https://" . $this->hs . "/_matrix/client/v2_alpha/register";
+        $handle = curl_init($url);
+        curl_setopt($handle, CURLOPT_RETURNTRANSFER, true);
+        curl_setopt($handle, CURLOPT_CONNECTTIMEOUT, 5);
+        curl_setopt($handle, CURLOPT_TIMEOUT, 60);
+        curl_setopt($handle, CURLOPT_HTTPHEADER, array("Content-Type: application/json"));
+        curl_setopt($handle, CURLOPT_POSTFIELDS, json_encode($data));
+
+        try {
+            return $this->exec_curl_request($handle);
+        } catch (Exception $e) {
+            if (strcmp("AUTHENTICATION_FAILED", $e->getMessage()) == 0) {
+                throw new Exception("WRONG_REGISTRATION_SHARED_SECRET");
+            } else {
+                throw $e;
+            }
+        }
+    }
+
+    function exec_curl_request($handle) {
+        $response = curl_exec($handle);
+        if ($response === false) {
+            $errno = curl_errno($handle);
+            $error = curl_error($handle);
+            error_log("Curl returned error $errno: $error\n");
+            curl_close($handle);
+            return false;
+        }
+        $http_code = intval(curl_getinfo($handle, CURLINFO_HTTP_CODE));
+        curl_close($handle);
+
+        if ($http_code >= 500) {
+            // do not want to DDOS server if something goes wrong
+            sleep(10);
+            return false;
+        } else if ($http_code != 200) {
+            $response = json_decode($response, true);
+            error_log("Request has failed with error {$response['error']}\n");
+            if ($http_code == 401) {
+                throw new Exception("AUTHENTICATION_FAILED");
+            }
+        } else {
+            $response = json_decode($response, true);
+        }
+        return $response;
+    }
+
+}
+
+class MatrixMessage {
+
+    private $message;
+
+    function __construct() {
+        $this->message = ["msgtype" => "m.notice"];
+    }
+
+    function set_type($msgtype) {
+        $this->message["msgtype"] = $msgtype;
+    }
+
+    function set_format($format) {
+        $this->message["format"] = $format;
+    }
+
+    function set_body($body) {
+        $this->message["body"] = $body;
+    }
+
+    function set_formatted_body($fbody, $format = "org.matrix.custom.html") {
+        $this->message["formatted_body"] = $fbody;
+        $this->message["format"] = $format;
+    }
+
+    function get_object() {
+        return $this->message;
+    }
+
+}
+
+?>

README.md

@@ -1,9 +1,73 @@
 # matrix-register-bot
+![state: alpha](https://img.shields.io/badge/state-alpha-yellowgreen.svg)
+[![#matrix-register-bot:msg-net.de](https://img.shields.io/badge/matrix-%23matrix--register--bot%3Amsg--net.de-brightgreen.svg)](https://matrix.to/#/#matrix-register-bot:msg-net.de)
 
-This bot provides a two-step-registration for matrix.
+This bot provides a two-step-registration for matrix ([synapse](https://github.com/matrix-org/synapse)).
 
 This is done in several steps:
-- potential new user registers on a bot-provided side
-- bot sends a message to prefined room with a registration notification.
+- potential new user registers on a bot-provided site
+- user has to verify its mail address
+- bot sends a message to predefined room with a registration notification.
 - users in that room now can approve or decline the registration.
-- The bot then uses the registration token to register the user or just drops the registration request.
+- When approved
+  - the bot creates short time credentials
+  - sends them to the user
+  - stores them encrypted in own databas or uses that as initial password for registration
+
+To configure synapse so that the users can login that were created via this bot you can either 
+- set `operationMode=synapse` so the bot uses the register api to push the new users to synapse or 
+- integrate it via [matrix-synapse-rest-auth](https://github.com/kamax-io/matrix-synapse-rest-auth#integrate) by configuring your system to point at `internal/login.php`.
+
+When using `operationMode=local` you can have the following benefits (some require [mxisd](https://github.com/kamax-io/mxisd/blob/master/docs/stores/rest.md))
+- Automatically set the display name based on first and last name on first login
+- Use the 3PID lookup for other users (only email)
+- Search for users that you have not seen yet
+
+## Requirements
+
+- Working PHP environment with
+  - database connection provider \[one of sqlite, mysql, postgres\]
+  - curl extension to notify admins and register users (in `operationMode=synapse`)
+  - mail capability to interact with the users (Verification, Approval (+ initial password), Notifications)
+- matrix-synapse-rest-auth when using `operationMode=local`
+- some PHP capable webserver which makes the folder `public` accessible to the public and propably `internal` for server-internal access
+
+## How to install
+
+- Copy `config.sample.php` to `config.php` and configure the bot as you can find there
+- Configure your webserver to have the folder `public` accessible via web.
+  The folder `internal` contains files that only provide API access. They can be accessed by mxisd or matrix-synapse-rest-auth 
+- To integrate with [matrix-synapse-rest-auth](https://github.com/kamax-io/matrix-synapse-rest-auth):
+  - `/_matrix-internal/identity/v1/check_credentials` should map to `internal/login.php`
+- To integrate with [mxisd](https://github.com/kamax-io/mxisd): Have a look at [the docs of mxisd](https://github.com/kamax-io/mxisd/blob/master/docs/stores/rest.md) and apply as follows:
+
+
+| Key                            | file which handles that       | Description                                          |
+|--------------------------------|-------------------------------|------------------------------------------------------|
+| rest.endpoints.auth            | internal/login.php            | Validate credentials and get user profile            |
+| rest.endpoints.directory       | internal/directory_search.php | Search for users by arbitrary input                  |
+| rest.endpoints.identity.single | internal/identity_single.php  | Endpoint to query a single 3PID                      |
+| rest.endpoints.identity.bulk   | internal/identity_bulk.php    | Endpoint to query a list of 3PID                     |
+
+
+## Further notes:
+
+### Security: Passwords from registration form are stored in clear text
+Currently the passwords which are typed in while capturing the register request are stored in clear text.
+The bot needs to access them to trigger a register request with correct credentials.
+It is currently strongly recommended to set `"getPasswordOnRegistration" => false` in your config!
+This leads to autocreating passwords which will then be send to the users directly without storing it.
+
+### Use the ChangePasswortInterceptor (if `operationMode=local`)
+
+To allow users to change their pasword you need a reverse proxy which maps `/_matrix/client/r0/account/password` to `internal/intercept_change_password.php`.
+Here is an example for nginx:
+```
+        location /_matrix/client/r0/account/password {
+                proxy_pass http://localhost/mxbot/internal/intercept_change_password.php;
+                proxy_set_header X-Forwarded-For $remote_addr;
+        }
+```
+### The bot postpones some actions
+There is a cron.php which implements retries and database cleanups (e.g. to remove a username claim)
+For this run cron.php regularly with your system of choice.

config.sample.php

@@ -0,0 +1,39 @@
+<?php
+$config = [
+    "homeserver" => "example.com",
+    "access_token" => "To be used for sending the registration notification",
+
+    // Which e-mail-adresse shall the bot use to send e-mails?
+    "register_email" => 'register_bot@example.com',
+    // Where should the bot post registration requests to?
+    "register_room" => '$registerRoomID:example.com',
+
+    // Where is the public part of the bot located? make sure you have a / at the end
+    "webroot" => "https://myregisterdomain.net/",
+
+    // optional: Do you have a place where howTo's are located? If not leave this value out
+    "howToURL" => "https://my-url-for-storing-howTos.net",
+
+    // set the mode of operation. Basically this defines where the data is stored:
+    // - synapse (using the register endpoint - so no further auth config necessary
+    // - local (recommended; using a table in the database to store credentials;
+    //   synapse has to be configured to use that)
+    "operationMode" => "local",
+
+    // This setting is only required for operationMode = synapse
+    "registration_shared_secret" => "SOME_SECRET_KEY_FROM_HOMESERVER_CONFIG",
+
+    // When you want to collect the password on registration set this to true
+    // only evaluated when operationMode = local
+    "getPasswordOnRegistration" => false,
+
+    // default language: one of [ en-gb | de-de ]
+    "defaultLanguage" => "en-gb",
+
+    // to define where the data should be stored:
+    "databaseURI" => "sqlite:" . dirname(__FILE__) . "/db_file.sqlite",
+    // credentials for sqlite not used
+    "databaseUser" => "dbUser123",
+    "databasePass" => "secretPassword",
+        ]
+?>

cron.php

@@ -0,0 +1,146 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/config.php");
+require_once(__DIR__ . "/language.php");
+require_once(__DIR__ . "/mail_templates.php");
+require_once(__DIR__ . "/database.php");
+
+$sql = "SELECT id, first_name, last_name, username, password, email,"
+        . " state, note, verify_token, admin_token "
+        . "FROM registrations "
+        . "WHERE state = " . RegisterState::PendingEmailSend
+        . " OR state = " . RegisterState::PendingAdminSend
+        . " OR state = " . RegisterState::PendingRegistration
+        . " OR state = " . RegisterState::PendingSendRegistrationMail . ";";
+foreach ($mx_db->query($sql) as $row) {
+    $first_name = $row["first_name"];
+    $last_name = $row["last_name"];
+    $username = $row["username"];
+    $email = $row["email"];
+    $state = $row["state"];
+
+    try {
+        switch ($state) {
+            case RegisterState::PendingEmailSend:
+                $verify_url = $config["webroot"] . "/verify.php?t=" . $row["verify_token"];
+                $success = send_mail_pending_verification(
+                        $config["homeserver"], $row["first_name"] . " " . $row["last_name"], $row["email"], $verify_url);
+
+                if ($success) {
+                    $mx_db->setRegistrationStateById(RegisterState::PendingEmailVerify, $row["id"]);
+                } else {
+                    throw new Exception("Could not send mail to " . $row["first_name"] . " " . $row["last_name"] . "(" . $row["id"] . ")");
+                }
+                break;
+            case RegisterState::PendingAdminSend:
+                require_once(__DIR__ . "/MatrixConnection.php");
+                $adminUrl = $config["webroot"] . "/verify_admin.php?t=" . $row["admin_token"];
+                $mxConn = new MatrixConnection($config["homeserver"], $config["access_token"]);
+                $mxMsg = new MatrixMessage();
+                $mxMsg->set_body(strtr($language["MSG_USER_WANTS_REGISTER"], [
+                    "@name" => (strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username),
+                    "@note" => $note,
+                    "@adminUrl" => $adminUrl
+                ]));
+                if (isset($language["MSG_USER_WANTS_REGISTER_FORMATTED"])) {
+                    $mxMsg->set_formatted_body(strtr($language["MSG_USER_WANTS_REGISTER_FORMATTED"], [
+                        "@name" => (strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username),
+                        "@note" => $note,
+                        "@adminUrl" => $adminUrl
+                    ]));
+                }
+                $mxMsg->set_type("m.text");
+                $response = $mxConn->send($config["register_room"], $mxMsg);
+
+                if ($response) {
+                    $mx_db->setRegistrationStateById(RegisterState::PendingAdminVerify, $row["id"]);
+
+                    send_mail_pending_approval($config["homeserver"], $first_name . " " . $last_name, $email);
+                } else {
+                    throw new Exception("Could not send notification for " . $row["first_name"] . " " . $row["last_name"] . "(" . $row["id"] . ") to admins.");
+                }
+                break;
+            case RegisterState::PendingRegistration:
+                // Registration got accepted but registration failed
+                switch ($config["operationMode"]) {
+                    case "synapse":
+                        // register with registration_shared_secret
+                        // generate a password with 10 characters
+                        $password = bin2hex(openssl_random_pseudo_bytes(5));
+                        $res = $mxConn->register($row["username"], $password, $config["registration_shared_secret"]);
+                        if (!$res) {
+                            // something went wrong while registering
+                            $password = NULL;
+                        }
+                        break;
+                    case "local":
+                        // register by adding a user to the local database
+                        $password = $mx_db->addUser($row["first_name"], $row["last_name"], $row["username"], $row["password"], $row["email"]);
+                        break;
+                    default:
+                        throw new Exception("Unknown operationMode");
+                }
+                if ($password != NULL) {
+                    // send registration_success
+                    $res = send_mail_registration_success(
+                            $config["homeserver"], strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username, $email, $username, $password, $config["howToURL"]
+                    );
+                    if ($res) {
+                        $mx_db->setRegistrationStateById(RegisterState::AllDone, $row["id"]);
+                    } else {
+                        $mx_db->setRegistrationStateById(RegisterState::PendingSendRegistrationMail, $row["id"]);
+                    }
+                } else {
+                    send_mail_registration_allowed_but_failed($config["homeserver"], $first_name . " " . $last_name, $email);
+                    $mxMsg = new MatrixMessage();
+                    $mxMsg->set_type("m.text");
+                    $mxMsg->set_body(strtr($language["REGISTRATION_FAILED_FOR"], [
+                        "@name" => strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username,
+                    ]));
+                    $mxConn->send($config["register_room"], $mxMsg);
+                    throw new Exception($language["REGISTRATION_FAILED"]);
+                }
+                break;
+            case RegisterState::PendingSendRegistrationMail:
+                print ("Error: Unhandled state: PendingSendRegistrationMail for " . $first_name . " " . $last_name . " (" . $username . ")\n");
+                break;
+        }
+    } catch (Exception $e) {
+        print("Error while handling cron for " . $first_name . " " . $last_name . " (" . $username . ")\n");
+        print($e->getMessage());
+    }
+}
+
+try {
+    //cleanup: all finished entries older than one month
+    $timestamp = date('Y-m-d H:m:s', strtotime("-1 month"));
+    $mx_db->query("DELETE FROM registrations "
+            . "WHERE request_date < '$timestamp'"
+            . " AND (state = " . RegisterState::RegistrationDeclined
+            . " OR state = " . RegisterState::AllDone . " );"
+    );
+    //cleanup: all entries which are pending email registration older than two days
+    $timestamp = date('Y-m-d H:m:s', strtotime("-2 days"));
+    $mx_db->query("DELETE FROM registrations "
+            . "WHERE request_date < '$timestamp'"
+            . " AND state = " . RegisterState::PendingEmailVerify . ";"
+    );
+} catch (Exception $e) {
+    print("Error while database cleanup\n");
+    print($e->getMessage());
+}
+?>

database.php

@@ -0,0 +1,371 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/config.php");
+if (!isset($config["databaseURI"])) {
+    throw new Exception("malformed configuration: databaseURI not defined");
+}
+
+abstract class RegisterState {
+
+    // Sending an E-Mail failed in the first attempt. Will retry later
+    const PendingEmailSend = 0;
+    // User got a mail. We wait for it to verfiy
+    const PendingEmailVerify = 1;
+    // Sending a message to the register room failed on first attempt
+    const PendingAdminSend = 5;
+    // No admin has verified the registration yet
+    const PendingAdminVerify = 6;
+    // Registration failed on first attempt. Will retry
+    const PendingRegistration = 7;
+    // in this case we have to reset the password of the user (or should we store it for this case?)
+    const PendingSendRegistrationMail = 8;
+    // State to allow persisting in the database although an admin declined it.
+    // Will be removed regularly
+    const RegistrationAccepted = 7;
+    const RegistrationDeclined = 13;
+    // User got successfully registered. Will be cleaned up later
+    const AllDone = 100;
+
+}
+
+class mxDatabase {
+
+    private $db = NULL;
+
+    /**
+     * Creates mxDatabase object
+     * @param config object which has following members:
+     *     databaseURI: path to the sqlite file where the credentials should be stored
+     *     or a param which can be used to connect to a database with PDO
+     * 	   databaseUser and databasePass when authentication is required
+     *     register_email which email does the register bot have (here used for providing lookup)
+     */
+    function __construct($config) {
+        if (empty($config)) {
+            throw new Exception("config is empty");
+        }
+        if (!isset($config["databaseURI"])) {
+            throw new Exception("'databaseURI' not defined");
+        }
+        $db_input = $config["databaseURI"];
+        $user = '';
+        $password = '';
+        if (isset($config["databaseUser"]) && isset($config["databasePass"])) {
+            // only use it when both are defined
+            $user = $config["databaseUser"];
+            $password = $config["databasePass"];
+        }
+        // create database file when not existent yet
+        $this->db = new PDO($db_input, $user, $password);
+        $this->db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+        $this->db->exec("CREATE TABLE IF NOT EXISTS registrations(
+			id SERIAL PRIMARY KEY,
+			state INT DEFAULT 0,
+			first_name TEXT,
+			last_name TEXT,
+			username TEXT,
+			password TEXT DEFAULT '',
+			note TEXT,
+			email TEXT,
+			verify_token TEXT,
+			admin_token TEXT,
+			request_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+			)");
+        $this->db->exec("CREATE TABLE IF NOT EXISTS logins (
+			id SERIAL PRIMARY KEY,
+			active INT DEFAULT 1,
+			first_name TEXT,
+			last_name TEXT,
+			localpart TEXT,
+			password_hash TEXT,
+			email TEXT,
+			create_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+			last_modified TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+			)");
+        // make sure the bot is allowed to login
+        if (!$this->userRegistered("register_bot")) {
+            $password = $this->addUser("Register", "Bot", "register_bot", NULL, $config["register_email"]);
+            $config["register_password"] = $password;
+            $myfile = fopen(dirname(__FILE__) . "/config.json", "w");
+            fwrite($myfile, json_encode($config, JSON_PRETTY_PRINT));
+            fclose($myfile);
+        }
+
+        // set writeable when not set already
+        if (strpos($db_input, "sqlite") === 0) {
+            $sqlite_file = substr($db_input, strlen("sqlite:"));
+            if (!is_writable($sqlite_file)) {
+                chmod($sqlite_file, 0660);
+            }
+            unset($sqlite_file);
+        }
+    }
+
+    /**
+     * WARNING: This allows accessing the database directly.
+     * This was only be added for convenience. You are advised to not use this function extensively
+     *
+     * @param sql String wich will be passed directly to the database
+     * @return Response of PDO::query()
+     */
+    function query($sql) {
+        return $this->db->query($sql);
+    }
+
+    function setRegistrationStateVerify($state, $token) {
+        $sql = "UPDATE registrations SET state = " . $state
+                . " WHERE verify_token = '" . $token . "';";
+
+        return $this->db->exec($sql);
+    }
+
+    function setRegistrationStateById($state, $id) {
+        $sql = "UPDATE registrations SET state = " . $state
+                . " WHERE id = '" . $id . "';";
+
+        return $this->db->exec($sql);
+    }
+
+    function setRegistrationStateAdmin($state, $token) {
+        $sql = "UPDATE registrations SET state = " . $state
+                . " WHERE admin_token = '" . $token . "';";
+
+        return $this->db->exec($sql);
+    }
+
+    function setRegistrationState($state, $token) {
+        $sql = "UPDATE registrations SET state = " . $state
+                . " WHERE verify_token = '" . $token . "' OR admin_token = '" . $token . "';";
+
+        return $this->db->exec($sql);
+    }
+
+    function userPendingRegistrations($username) {
+        $sql = "SELECT COUNT(*) FROM registrations WHERE username = '" . $username . "' AND NOT state = "
+                . RegisterState::RegistrationDeclined . " LIMIT 1;";
+        $res = $this->db->query($sql);
+        if ($res->fetchColumn() > 0) {
+            return true;
+        }
+        return false;
+    }
+
+    function userRegistered($username) {
+        $sql = "SELECT COUNT(*) FROM logins WHERE localpart = '" . $username . "' LIMIT 1;";
+        $res = $this->db->query($sql);
+        if ($res->fetchColumn() > 0) {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Adds user to the database. Next steps should be sending a verify-mail to the user
+     * @param first_name First name of the user
+     * @param last_name Sirname of the user
+     * @param username the future localpart of that user
+     * @param note Note the user typed in to give a hint
+     * @param email E-Mail-Adress which will be stored into the database.
+     * 			This will be send to the server on first login
+     *
+     * @return ["verify_token"]
+     */
+    function addRegistration($first_name, $last_name, $username, $password, $note, $email) {
+        if ($this->userPendingRegistrations($username)) {
+            throw new Exception("USERNAME_PENDING_REGISTRATION");
+        }
+        if ($this->userRegistered($username)) {
+            throw new Exception("USERNAME_REGISTERED");
+        }
+
+        $verify_token = bin2hex(random_bytes(16));
+        $admin_token = bin2hex(random_bytes(16));
+
+        $this->db->exec("INSERT INTO registrations
+                (first_name, last_name, username, password, note, email, verify_token, admin_token)
+		VALUES ('" . $first_name . "','" . $last_name . "','"
+                . $username . "','" . $password . "','" . $note . "','"
+                . $email . "','" . $verify_token . "','" . $admin_token . "')");
+
+        return [
+            "verify_token" => $verify_token,
+        ];
+    }
+
+    /**
+     * Gets the user for the verify_admin page.
+     *
+     * @return ArrayOfUser|NULL Array with "first_name, last_name, username, note and email"
+     * 		as members
+     */
+    function getUserForApproval($admin_token) {
+        $sql = "SELECT COUNT(*) FROM registrations WHERE admin_token = '" . $admin_token . "'"
+                . " AND state = " . RegisterState::PendingAdminVerify . " LIMIT 1;";
+        $res = $this->db->query($sql);
+
+        if ($res->fetchColumn() > 0) {
+            $sql = "SELECT first_name, last_name, username, password, note, email FROM registrations"
+                    . " WHERE admin_token = '" . $admin_token . "'"
+                    . " AND state = " . RegisterState::PendingAdminVerify
+                    . " LIMIT 1;";
+            foreach ($this->db->query($sql) as $row) {
+                // will only be executed once
+                return $row;
+            }
+        }
+        return NULL;
+    }
+
+    /**
+     * Gets the user when it opens the page to verify its mail
+     *
+     * @return ArrayOfUser|NULL Array with "first_name, last_name, note, email and admin_token"
+     * 		as members
+     */
+    function getUserForVerify($verify_token) {
+        $sql = "SELECT COUNT(*) FROM registrations WHERE verify_token = '" . $verify_token . "'"
+                . " AND state = " . RegisterState::PendingEmailVerify . " LIMIT 1;";
+        $res = $this->db->query($sql);
+
+        if ($res->fetchColumn() > 0) {
+            $sql = "SELECT first_name, last_name, note, email, username, admin_token FROM registrations "
+                    . " WHERE verify_token = '" . $verify_token . "'"
+                    . " AND state = " . RegisterState::PendingEmailVerify . " LIMIT 1;";
+            foreach ($this->db->query($sql) as $row) {
+                // will only be executed once
+                return $row;
+            }
+        }
+        return NULL;
+    }
+
+    function getUserForLogin($localpart, $password) {
+        $sql = "SELECT COUNT(*) FROM logins WHERE localpart = '" . $localpart
+                . "' AND active = 1 LIMIT 1;";
+        $res = $this->db->query($sql);
+
+        if ($res->fetchColumn() > 0) {
+            $sql = "SELECT first_name, last_name, email, password_hash FROM logins "
+                    . " WHERE localpart = '" . $localpart . "' AND active = 1 LIMIT 1;";
+            foreach ($this->db->query($sql) as $row) {
+                if (password_verify($password, $row["password_hash"])) {
+                    return $row;
+                }
+            }
+        }
+        return NULL;
+    }
+
+    /**
+     * adds User to be able to login afterwards.
+     * @param first_name First name of the user
+     * @param last_name Sirname of the user
+     * @param username the future localpart of that user
+     * @param email E-Mail-Adress which will be stored into the database.
+     * 			This will be send to the server on first login
+     *
+     * @return password|NULL with member password as this method generates a
+     * 			password and saves that into the database
+     * 			NULL when failed
+     *
+     */
+    function addUser($first_name, $last_name, $username, $password, $email) {
+        // check if user already exists and abort in that case
+        if ($this->userRegistered($username)) {
+            return NULL;
+        }
+
+        if ($password == NULL) {
+            // generate a password with 10 characters
+            $password = bin2hex(openssl_random_pseudo_bytes(5));
+        }
+        $password_hash = password_hash($password, PASSWORD_BCRYPT, ["cost" => 12]);
+
+        $sql = "INSERT INTO logins (first_name, last_name, localpart, password_hash, email) VALUES "
+                . "('" . $first_name . "','" . $last_name . "','" . $username . "','"
+                . $password_hash . "','" . $email . "');";
+
+        if ($this->db->exec($sql)) {
+            return $password;
+        }
+        return NULL;
+    }
+
+    function updatePassword($localpart, $old_password, $new_password) {
+        $user = $this->getUserForLogin($localpart, $old_password);
+        if ($user == NULL) {
+            throw new Exception("user with that credentials not found");
+        }
+
+        // The credentials were fine. So now set the new password
+        $password_hash = password_hash($new_password, PASSWORD_BCRYPT, ["cost" => 12]);
+
+        $sql = "UPDATE logins SET password_hash = '" . $password_hash . "'"
+                . "WHERE localpart = '" . $localpart . "'";
+
+        if ($this->db->exec($sql)) {
+            return true;
+        }
+        return false;
+    }
+
+    function searchUserByName($search_term) {
+        $term = filter_var($search_term, FILTER_SANITIZE_STRING);
+        $result = array();
+        $sql = "SELECT COUNT(*) FROM logins WHERE"
+                . " localpart LIKE '" . $term . "%' AND active = 1;";
+        $res = $this->db->query($sql);
+
+        if ($res->fetchColumn() > 0) {
+            $sql = "SELECT first_name, last_name, localpart FROM logins WHERE"
+                    . " localpart LIKE '" . $term . "%' AND active = 1;";
+            foreach ($this->db->query($sql) as $row) {
+                array_push($result, [
+                    "display_name" => $row["first_name"] . " " . $row["last_name"],
+                    "user_id" => $row["localpart"],
+                ]);
+            }
+        }
+        return $result;
+    }
+
+    function searchUserByEmail($search_term) {
+        $term = filter_var($search_term, FILTER_SANITIZE_STRING);
+        $result = array();
+        $sql = "SELECT COUNT(*) FROM logins WHERE"
+                . " email = '" . $term . "' AND active = 1;";
+        $res = $this->db->query($sql);
+
+        if ($res->fetchColumn() > 0) {
+            $sql = "SELECT first_name, last_name, localpart FROM logins WHERE"
+                    . " email = '" . $term . "' AND active = 1;";
+            foreach ($this->db->query($sql) as $row) {
+                array_push($result, [
+                    "display_name" => $row["first_name"] . " " . $row["last_name"],
+                    "user_id" => $row["localpart"],
+                ]);
+            }
+        }
+        return $result;
+    }
+
+}
+
+if (!isset($mx_db)) {
+    $mx_db = new mxDatabase($config);
+}
+?>

helpers.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+function stripLocalpart($mxid) {
+    $localpart = NULL;
+    if (!empty($mxid)) {
+        // A mxid would start with an @ so we start at the 2. position
+        $sepPos = strpos($mxid, ':', 1);
+        if ($sepPos === false) {
+            // : not found. Assume mxid is localpart
+            // TODO: further checks
+            $localpart = $mxid;
+        } else {
+            $localpart = substr($mxid, 1, strpos($mxid, ':') - 1);
+        }
+    }
+    return $localpart;
+}
+
+?>

internal/directory_search.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/../database.php");
+$response = [
+    "limited" => false,
+    "result" => [],
+];
+
+try {
+    $inputJSON = file_get_contents('php://input');
+    $input = json_decode($inputJSON, TRUE);
+    if (empty($input)) {
+        throw new Exception('no valid json as input present');
+    }
+    if (!isset($input["by"])) {
+        throw new Exception('"by" is not defined');
+    }
+    if (!isset($input["search_term"])) {
+        throw new Exception('"search_term" is not defined');
+    }
+    switch ($input["by"]) {
+        case "name":
+            $response["result"] = $mx_db->searchUserByName($input["search_term"]);
+            break;
+        case "threepid":
+            $response["result"] = $mx_db->searchUserByEmail($input["search_term"]);
+            break;
+        default:
+            throw new Exception('unknown type for "by" param');
+    }
+} catch (Exception $e) {
+    error_log("failed with error: " . $e->getMessage());
+    $response["error"] = $e->getMessage();
+}
+print (json_encode($response, JSON_PRETTY_PRINT));
+?>

internal/identity_bulk.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/../database.php");
+$response = [
+    "lookup" => []
+];
+try {
+    $inputJSON = file_get_contents('php://input');
+    $input = json_decode($inputJSON, TRUE);
+    if (!isset($input)) {
+        throw new Exception('request body is no valid json');
+    }
+
+    if (!isset($input["lookup"])) {
+        throw new Exception('"lookup" is not defined');
+    }
+    if (!is_array($input["lookup"])) {
+        throw new Exception('"lookup" is not an array');
+    }
+    foreach ($input["lookup"] as $lookup) {
+        if (!isset($lookup["medium"])) {
+            throw new Exception('"lookup.medium" is not defined');
+        }
+        if (!isset($lookup["address"])) {
+            throw new Exception('"lookup.address" is not defined');
+        }
+        $res2 = NULL;
+        switch ($lookup["medium"]) {
+            case "email":
+                $res2 = $mx_db->searchUserByEmail($lookup["address"]);
+                if (!empty($res2)) {
+                    array_push($response["lookup"], [
+                        "medium" => $lookup["medium"],
+                        "address" => $lookup["address"],
+                        "id" => [
+                            "type" => "localpart",
+                            "value" => $res2[0]["user_id"],
+                        ]
+                            ]
+                    );
+                }
+                break;
+            case "msisdn":
+                // This is reserved for number lookups
+                throw new Exception("unimplemented lookup medium");
+                break;
+            default:
+                throw new Exception("unknown lookup medium");
+        }
+    }
+} catch (Exception $e) {
+    error_log("ídentity_bulk failed with error: " . $e->getMessage());
+    $response["error"] = $e->getMessage();
+}
+print (json_encode($response, JSON_PRETTY_PRINT));
+?>

internal/identity_single.php

@@ -0,0 +1,65 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/../database.php");
+$response = new stdClass;
+try {
+    $inputJSON = file_get_contents('php://input');
+    $input = json_decode($inputJSON, TRUE);
+    if (empty($input)) {
+        throw new Exception('no valid json as input present');
+    }
+    if (!isset($input["lookup"])) {
+        throw new Exception('"lookup" is not defined');
+    }
+    if (!isset($input["lookup"]["medium"])) {
+        throw new Exception('"lookup.medium" is not defined');
+    }
+    if (!isset($input["lookup"]["address"])) {
+        throw new Exception('"lookup.address" is not defined');
+    }
+    $res2 = NULL;
+    switch ($input["lookup"]["medium"]) {
+        case "email":
+            $res2 = $mx_db->searchUserByEmail($input["lookup"]["address"]);
+            if (!empty($res2)) {
+                $response = [
+                    "lookup" => [
+                        "medium" => $input["lookup"]["medium"],
+                        "address" => $input["lookup"]["address"],
+                        "id" => [
+                            "type" => "localpart",
+                            "value" => $res2[0]["user_id"],
+                        ]
+                    ]
+                ];
+            }
+            break;
+        case "msisdn":
+            // This is reserved for number lookups
+            throw new Exception("unimplemented lookup medium");
+            break;
+        default:
+            throw new Exception("unknown lookup medium");
+    }
+} catch (Exception $e) {
+    error_log("ídentity_single failed with error: " . $e->getMessage());
+    $response = [
+        "error" => $e->getMessage()
+    ];
+}
+print (json_encode($response, JSON_PRETTY_PRINT));
+?>

internal/intercept_change_password.php

@@ -0,0 +1,69 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+// URL for this: /_matrix/client/r0/account/password?access_token=$ACCESS_TOKEN
+
+header('Access-Control-Allow-Origin: *');
+header('Access-Control-Allow-Methods: POST, OPTIONS');
+header('Access-Control-Allow-Headers: Origin, X-Requested-With, Content-Type, Accept, Authorization');
+if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
+    print ("{}");
+    // return with success
+    exit();
+}
+$response = new stdClass;
+try {
+    $inputJSON = file_get_contents('php://input');
+    $input = json_decode($inputJSON, TRUE);
+    if (empty($input)) {
+        throw new Exception('no valid json as input present');
+    }
+    if (!isset($input["auth"])) {
+        throw new Exception('"auth" is not defined');
+    }
+    if (!isset($input["auth"]["user"]) || !isset($input["auth"]["password"])) {
+        throw new Exception('"auth.user" or "auth.password" is not defined');
+    }
+    if (!isset($input["auth"]["type"]) || $input["auth"]["type"] !== "m.login.password") {
+        throw new Exception('no or unknown auth.type');
+    }
+    if (!isset($input["new_password"])) {
+        throw new Exception('"new_password" is not defined');
+    }
+
+    require_once(__DIR__ . "/../helpers.php");
+    $localpart = stripLocalpart($input["auth"]["user"]);
+
+    if (empty($localpart)) {
+        throw new Exception("localpart cannot be identified");
+    }
+
+    require_once(__DIR__ . "/../database.php");
+    if (!$mx_db->updatePassword(
+                    $localpart, $input["auth"]["password"], $input["new_password"]
+            )) {
+        throw new Exception("invalid credentials or another error while updating");
+    }
+} catch (Exception $e) {
+    header("HTTP/1.0 500 Internal Error");
+    error_log("failed with error: " . $e->getMessage());
+    $response = [
+        "errorcode" => "M_UNKNOWN",
+        "error" => $e->getMessage(),
+    ];
+}
+print (json_encode($response, JSON_PRETTY_PRINT));
+?>

internal/login.php

@@ -0,0 +1,112 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+$response = [
+    "auth" => [
+        "success" => false,
+    ]
+];
+
+require_once(__DIR__ . "/../database.php");
+
+abstract class LoginRequester {
+
+    const UNDEFINED = 0;
+    const MXISD = 1;
+    const RestAuth = 2;
+
+}
+
+$loginRequester = LoginRequester::UNDEFINED;
+
+try {
+    $inputJSON = file_get_contents('php://input');
+    $input = json_decode($inputJSON, TRUE);
+    $mxid = $localpart = NULL;
+    if (isset($input["user"])) {
+        if (isset($input["user"]["localpart"])) {
+            $localpart = $input["user"]["localpart"];
+            $loginRequester = LoginRequester::MXISD;
+        } elseif (isset($input["user"]["id"])) {
+            // compatibility for matrix-synapse-rest-auth
+            $mxid = $input["user"]["id"];
+            $loginRequester = LoginRequester::RestAuth;
+        } elseif (isset($input["user"]["mxid"])) {
+            // compatibility for mxisd
+            $mxid = $input["user"]["mxid"];
+            $loginRequester = LoginRequester::MXISD;
+        }
+    } else {
+        throw new Exception('"user" not in request body');
+    }
+
+    // prefer the localpart attribute of mxisd. But in case of matrix-synapse-rest-auth
+    // we have to parse it on our own
+    if (empty($localpart)) {
+        require_once(__DIR__ . "/../helpers.php");
+        $localpart = stripLocalpart($mxid);
+    }
+
+    if (empty($localpart)) {
+        throw new Exception("localpart cannot be identified");
+    }
+
+    $password = NULL;
+    if (isset($input["user"]["password"])) {
+        $password = $input["user"]["password"];
+    }
+    if (empty($password)) {
+        throw new Exception("password is not present");
+    }
+
+    $user = $mx_db->getUserForLogin($localpart, $password);
+    if (!$user) {
+        throw new Exception("user not found or password did not match");
+    }
+    $response["auth"]["success"] = true;
+    $response["auth"]["profile"] = [
+        "display_name" => $user["first_name"] . " " . $user["last_name"],
+        "three_pids" => [
+            [
+                "medium" => "email",
+                "address" => $user["email"],
+            ],
+        ],
+    ];
+
+    switch ($loginRequester) {
+        case LoginRequester::RestAuth:
+            $response["auth"]["mxid"] = $mxid;
+            break;
+        case LoginRequester::MXISD;
+            $response["auth"]["id"] = [
+                "type" => "localpart",
+                "value" => $localpart,
+            ];
+            break;
+        default:
+            // only return that it was successful.
+            // we do not know how the data shall be transmitted so we do nothing with it
+            $response["auth"]["success"] = false;
+            $response["auth"]["error"] = "unidentified requester";
+            break;
+    }
+} catch (Exception $e) {
+    error_log("Auth failed with error: " . $e->getMessage());
+    $response["auth"]["error"] = $e->getMessage();
+}
+print (json_encode($response, JSON_PRETTY_PRINT));
+?>

lang/lang.de-de.php

@@ -0,0 +1,71 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+$language = array(
+    "ACCEPT" => "Akzeptieren",
+    "DECLINE" => "Ablehnen",
+    "SUCCESS" => "Erfolgreich",
+    "FIRST_NAME" => "Vorname",
+    "LAST_NAME" => "Nachname",
+    "USERNAME" => "Nutzername (für den Login)",
+    "PASSWORD" => "Passwort",
+    "PASSWORD_CONFIRM" => "Passwort bestätigen",
+    "EMAIL_ADDRESS" => "E-Mail-Adresse",
+    "REGISTER" => "Registrieren",
+    "NOTE" => "Hinweis",
+    "NO_CONFIGURATION" => "Es konnte keine Konfiguration gefunden werden.",
+    "UNKNOWN_ERROR" => "Unbekannter Fehler",
+    "UNKNOWN_SESSION" => "Sitzungstoken nicht vorhanden oder ungültig.",
+    "UNKNOWN_USERNAME" => "Nutzername fehlt",
+    "UNKNOWN_TOKEN" => "Token ist unbekannt",
+    "AUTHENTICATION_FAILED" => "Authentifizierung fehlgeschlagen",
+    "WRONG_REGISTRATION_SHARED_SECRET" => "registration_shared_secret fehlerhaft",
+    "USERNAME_INVALID" => "Nutzername muss aus 3 bis 20 Kleinbuchstaben bestehen",
+    "USERNAME_NOT_ALNUM" => "Nutzername ist nicht alphanumerisch",
+    "USERNAME_PENDING_REGISTRATION" => "Dieser Nutzername wurde bereits zur Registrierung vorgemerkt. Versuche es später noch einmal oder wähle einen anderen Nutzernamen",
+    "USERNAME_REGISTERED" => "Dieser Nutzername wurde bereits registriert. Bitte wähle einen anderen Nutzernamen",
+    "PASSWORD_NOT_PROVIDED" => "Ein oder beide Passwörter wurden nicht gesetzt",
+    "PASSWORD_NOT_MATCH" => "Passwörter stimmen nicht überein",
+    "NOTE_LENGTH_EXEEDED" => "Notiz ist länger als die erlaubten 50 Zeichen",
+    "PLACEHOLDER_NOTE_ABOUT_YOURSELF" => "Notiz zu dir (max. 50 Zeichen)",
+    "EMAIL_INVALID_FORMAT" => "Keine valide E-Mail-Adresse angegeben",
+    "FIRSTNAME_INVALID_FORMAT" => "Vorname muss das Format <Großbuchstabe><Kleinbuchstaben> haben",
+    "SIRNAME_INVALID_FORMAT" => "Nachname muss das Format <Großbuchstabe><Kleinbuchstaben> haben",
+    "SEND_MAIL_FAIL" => "Senden der E-Mail fehlgeschlagen",
+    "SEND_MATRIX_FAIL" => "Senden einer Nachricht an die Administratoren fehlgeschlagen",
+    "TASK_CHECK_YOUR_EMAIL_VERIFY" => "Bitte prüfe deine E-Mails um deine Adresse zu bestätigen",
+    "REGISTRATION_REQUEST_FAILED" => "Registrierungsanfrage ist fehlgeschlagen",
+    "REGISTRATION_FAILED" => "Registrierung ist fehlgeschlagen",
+    "REGISTRATION_FAILED_FOR" => "Registrierung für @user ist fehlgeschlagen",
+    "VERIFICATION_SUCEEDED" => "Verifizierung erfolgreich",
+    "VERIFICATION_FAILED" => "Verifizierung fehlgeschlagen",
+    "VERIFICATION_SUCCESS_BODY" => "Vielen Dank. Die Administratoren wurden informiert",
+    "ADMIN_VERIFY_SITE_TITLE" => "Registrierungsanfrage bearbeiten",
+    "ADMIN_REGISTER_ACCEPTED_BODY" => "Die Registrierungsanfrage wurde akzeptiert. Der Nutzer wurde per Mail informiert.",
+    "ADMIN_REGISTER_DECLINED_BODY" => "Die Registrierungsanfrage wurde angelehnt. Der Nutzer wurde per Mail informiert.",
+    "JUMP_TO_HOMEPAGE" => "Zur Startseite",
+    "TOPIC_PLEASE_REGISTER" => "Bitte für @homeserver registrieren",
+    "TOPIC_PLEASE_REGISTER_NOTE" => "2-Schritt-Registrierung",
+    "NOTE_FOR_REGISTRATION" => "@homeserver ist ein geschlossenes Chat-Netzwerk in dem jeder Nutzer bestätigt werden muss.<br />
+        Du bekommst eine E-Mail wenn jemand deine Mitgliedschaft bestätigt hat. An diese wird auch dein initiales Passwort gesendet.
+        Hinterlasse also bitte einen Hinweis zu dir (den nur die Administratoren sehen werden).<br />
+        Liebe Grüße vom Team von @homeserver",
+    "MSG_USER_WANTS_REGISTER" => "@name möchte sich registrieren und hat folgende Notiz hinterlassen:
+            @note \r\nZum Bearbeiten hier klicken:\r\n @adminUrl",
+    "MSG_USER_WANTS_REGISTER_FORMATTED" => "@name möchte sich registrieren und hat folgende Notiz hinterlassen:<br />
+                @note <br />Zum Bearbeiten <a href=\"@adminUrl\">hier</a> klicken",
+);
+?>

lang/lang.en-gb.php

@@ -0,0 +1,71 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+$language = array(
+    "ACCEPT" => "Accept",
+    "DECLINE" => "Decline",
+    "SUCCESS" => "Success",
+    "FIRST_NAME" => "First name",
+    "LAST_NAME" => "Last name",
+    "USERNAME" => "username (for login)",
+    "PASSWORD" => "Password",
+    "PASSWORD_CONFIRM" => "Confirm password",
+    "EMAIL_ADDRESS" => "EMail Address",
+    "REGISTER" => "Register",
+    "NOTE" => "Note",
+    "NO_CONFIGURATION" => "No configuration found",
+    "UNKNOWN_ERROR" => "Unknown Error",
+    "UNKNOWN_SESSION" => "Session token not found of invalid.",
+    "UNKNOWN_USERNAME" => "username unknown",
+    "UNKNOWN_TOKEN" => "Token is unknown",
+    "AUTHENTICATION_FAILED" => "Authentication failed",
+    "WRONG_REGISTRATION_SHARED_SECRET" => "wrong registration_shared_secret",
+    "USERNAME_INVALID" => "Username has to consist of 3 to 20 small letters",
+    "USERNAME_NOT_ALNUM" => "Username is not alphanumeric",
+    "USERNAME_PENDING_REGISTRATION" => "This username is locked for registration. Try again later or try again with a different username",
+    "USERNAME_REGISTERED" => "This username is already registered. Please try again with another username",
+    "PASSWORD_NOT_PROVIDED" => "One or both passwords are not provided",
+    "PASSWORD_NOT_MATCH" => "passwords do not match",
+    "NOTE_LENGTH_EXEEDED" => "Note consists of more than 50 characters",
+    "PLACEHOLDER_NOTE_ABOUT_YOURSELF" => "Note about yourself (max. 50 characters)",
+    "EMAIL_INVALID_FORMAT" => "no valid email address",
+    "FIRSTNAME_INVALID_FORMAT" => "First name with invalid formatting",
+    "SIRNAME_INVALID_FORMAT" => "Sirname with invalid formatting",
+    "SEND_MAIL_FAIL" => "Email could not be sent",
+    "SEND_MATRIX_FAIL" => "Sending a message to the admins failed",
+    "TASK_CHECK_YOUR_EMAIL_VERIFY" => "Please check your emails to verify your email address",
+    "REGISTRATION_REQUEST_FAILED" => "Registration request failed",
+    "REGISTRATION_FAILED" => "Registration failed",
+    "REGISTRATION_FAILED_FOR" => "Registrierung für @user ist fehlgeschlagen",
+    "VERIFICATION_SUCEEDED" => "Verification suceeded",
+    "VERIFICATION_FAILED" => "Verification failed",
+    "VERIFICATION_SUCCESS_BODY" => "Thank you. The admins got informed",
+    "ADMIN_VERIFY_SITE_TITLE" => "Handle registration request",
+    "ADMIN_REGISTER_ACCEPTED_BODY" => "The registration request got accepted. The user got notified per email.",
+    "ADMIN_REGISTER_DECLINED_BODY" => "The registration request got declined. The user got notified per email.",
+    "JUMP_TO_HOMEPAGE" => "To homepage",
+    "TOPIC_PLEASE_REGISTER" => "Please register for @homeserver",
+    "TOPIC_PLEASE_REGISTER_NOTE" => "2-Step-Registration",
+    "NOTE_FOR_REGISTRATION" => "@homeserver is a closed chat network where every user has to be confirmed.<br />
+        You will get an email once sb. approved your registration. An initial password will be send to you afterwards.
+        Please leave a note about yourself (that will only be shown to the admins).<br />
+        Greetings from the team of @homeserver",
+    "MSG_USER_WANTS_REGISTER" => "@name wants to register and left the following note:
+            @note \r\nTo handle that request:\r\n @adminUrl",
+    "MSG_USER_WANTS_REGISTER_FORMATTED" => "@name wants to register and left the following note:<br />
+                @note <br />To handle that request click <a href=\"@adminUrl\">here</a>",
+);
+?>

lang/mail.de-de.php

@@ -0,0 +1,125 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+function send_mail($receiver, $subject, $body) {
+    include(__DIR__ . "/../config.php");
+    $headers = "From: " . $config["register_email"] . "\r\n"
+            . "Content-Type: text/plain;charset=utf-8";
+    return mail($receiver, $subject, $body, $headers);
+}
+
+function send_mail_pending_verification($homeserver, $user, $receiver, $verify_url) {
+    $subject = "Bitte bestätige Registrierung auf $homeserver";
+    $body = "Guten Tag " . $user . ",
+
+Du hast anscheinend versucht dich auf $homeserver zu registrieren.
+Hier gibt es eine zweistufige Registrierung.
+
+Wir möchten dich bitten, dass du kurz bestätigst, dass du die Registrierung durchgeführt hast.
+Gehe dafür auf folgenden Link:
+$verify_url
+
+Erst anschließend werden die Administratoren über deine Registrierungsanfrage informiert.
+
+Hinweis: Du hast ca. 48 Stunden Zeit um die Bestätigung durchzuführen.
+Danach ist eine Re-Registrierung mit deinem gewünschten Nutzernamen für andere wieder möglich.
+
+Vielen Dank für dein Verständnis.
+
+Das Administratoren-Team von " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+function send_mail_pending_approval($homeserver, $user, $receiver) {
+    $subject = "Registrierung wartet auf Bestätigung durch Administratoren";
+    $body = "Guten Tag " . $user . ",
+
+Deine Registrierungsanfrage wurde verifiziert und wird nun durch die Administratoren überprüft.
+
+Du bekommst eine weitere E-Mail, sobald deine Registrierung bestätigt oder ablehnt wurde.
+
+Vielen Dank für dein Verständnis.
+
+Das Administratoren-Team von " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+function send_mail_registration_allowed_but_failed($homeserver, $user, $receiver) {
+    $subject = "Registrierung auf $homeserver genehmigt";
+    $body = "Guten Tag " . $user . ",
+
+Deine Registrierungsanfrage wurde durch die Administratoren bestätigt.
+
+Leider ist beim Registrieren ein Fehler aufgetaucht. Der Registrierungversuch wird bald wiederholt.
+Wir hoffen, das Problem ist bald behoben.
+Wir melden uns, wenn die Registrierung erfolgreich war.
+
+Das Administratoren-Team von " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+function send_mail_registration_success($homeserver, $user, $receiver, $username, $password, $howToURL) {
+    $subject = "Registrierung auf $homeserver erfolgreich";
+    $body = "Guten Tag " . $user . ",
+
+Deine Registrierungsanfrage wurde durch die Administratoren bestätigt.
+
+Zum Anmelden kannst du folgende Zugangsdaten verwenden:
+Nutzername: $username
+Passwort: " . (empty($password) ? "wie selbst gesetzt": $password) . "
+
+Hinweis: Das Passwort kannst du aktuell über die App selbst ändern. Auch wenn das Passwort nirgends
+im Klartext gespeichert wird, kann jemand Zugriff auf diese Mail erlangen und so den Zugriff bekommen.
+";
+    /*
+      Wichtig: Bitte ändere das Passwort direkt nach der Anmeldung.
+      Es wird zwar von unserer Seite nicht gespeichert, doch fremde könnten Zugriff auf diese E-Mail
+      erhalten und so deinen Account kompromittieren.
+     */
+    if (!empty($howToURL)) {
+        $body .= "
+Zu weiteren Hilfestellungen findest du hier eine Auflistung von verschiedenen
+Anleitungen zu verschiedenen Clients:
+$howToURL\n";
+    }
+    $body .= "
+Viel Spaß bei der Verwendung von $homeserver.
+Bei Fragen findest du nach der Anmeldung ein paar Räume in denen du sie stellen kannst.
+
+Das Administratoren-Team von " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+function send_mail_registration_decline($homeserver, $user, $receiver, $reason) {
+    $subject = "Registrierung auf $homeserver abgelehnt";
+    $body = "Guten Tag " . $user . ",
+
+Deine Registrierungsanfrage wurde durch die Administratoren abgelehnt.\n";
+
+    if (empty($reason)) {
+        $body .= "\nEs wurde kein Grund angegeben\n";
+    } else {
+        $body .= "\nAls Grund wurde folgendes angegeben:\n$reason\n";
+    }
+
+    $body .= "
+Wir hoffen, dass du dies akzeptieren kannst.
+
+Das Administratoren-Team von " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+?>

lang/mail.en-gb.php

@@ -0,0 +1,119 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+function send_mail($receiver, $subject, $body) {
+    include(__DIR__ . "/../config.php");
+    $headers = "From: " . $config["register_email"] . "\r\n"
+            . "Content-Type: text/plain;charset=utf-8";
+    return mail($receiver, $subject, $body, $headers);
+}
+
+function send_mail_pending_verification($homeserver, $user, $receiver, $verify_url) {
+    $subject = "Pleast approve your registration request on $homeserver";
+    $body = "Dear " . $user . ",
+
+It seems that you tried to register on $homeserver.
+This homeserver requires a two step registration.
+
+For this we want you to verify that you want to register. For this please click on this link:
+$verify_url
+
+The admins will informed about your registration request once you clicked on this link.
+
+Note: This registration request will be cleaned up in 48 hours.
+Others might take your username afterwards.
+
+Thanks for your patience.
+
+The admin team of " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+function send_mail_pending_approval($homeserver, $user, $receiver) {
+    $subject = "Registration is pending verification from an admin";
+    $body = "Dear " . $user . ",
+
+You have verified your registration request. The admins are now checking your request.
+
+You will get an email once they approve or decline your request.
+
+Sincerely,
+
+The admin team of " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+function send_mail_registration_allowed_but_failed($homeserver, $user, $receiver) {
+    $subject = "Registration on $homeserver got approved";
+    $body = "Dear " . $user . ",
+
+Your registration request got approved by the admin team.
+
+But there was a problem when triggering the registration request. It will be retried in a few minutes.
+We hope that the issue will be fixed soon.
+You will get another email with initial credentials once the registration got handled completely.
+
+The admin team of " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+function send_mail_registration_success($homeserver, $user, $receiver, $username, $password, $howToURL) {
+    $subject = "Registration on $homeserver got approved";
+    $body = "Dear " . $user . ",
+
+Your registration request got verified by the admin team.
+
+To log in you can use the following credentials::
+Username: $username
+Passwort: " . (empty($password) ? "as self-set": $password) . "
+
+Important: Please change your password as soon as possible after your first login.
+The password is not stored in clear text on the server but people could get access to this mail
+and compromise your account.
+";
+    if (!empty($howToURL)) {
+        $body .= "
+You can find further help here::
+$howToURL\n";
+    }
+    $body .= "
+Enjoy your usage of $homeserver.
+You can ask further questions inside of the chat system.
+
+The admin team of " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+function send_mail_registration_decline($homeserver, $user, $receiver, $reason) {
+    $subject = "Registration on $homeserver declined.";
+    $body = "Guten Tag " . $user . ",
+
+Your registration request got declined by the admin team.\n";
+
+    if (empty($reason)) {
+        $body .= "\nThey did not provide any reason for this\n";
+    } else {
+        $body .= "\nThey provide following hint for you:\n$reason\n";
+    }
+
+    $body .= "
+We hope that you can understand this reason.
+
+The admin team of " . $homeserver;
+    return send_mail($receiver, $subject, $body);
+}
+
+?>

language.php

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/config.php");
+$lang = $config["defaultLanguage"];
+
+if (isset($_GET['lang'])) {
+    $lang = filter_var($_GET['lang'], FILTER_SANITIZE_STRING);
+}
+$lang_file = dirname(__FILE__) . "/lang/lang." . $lang . ".php";
+if (!file_exists($lang_file)) {
+    error_log("Translation for " . $lang . " not found. Fallback to 'de-de'");
+    $lang = "de-de";
+}
+$lang_file = __DIR__ . "/lang/lang." . $lang . ".php";
+require_once($lang_file);
+unset($lang_file);
+?>

mail_templates.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/config.php");
+$lang = $config["defaultLanguage"];
+if (isset($_GET['lang'])) {
+    $lang = filter_var($_GET['lang'], FILTER_SANITIZE_STRING);
+}
+$lang_file = __DIR__ . "/lang/mail." . $lang . ".php";
+if (!file_exists($lang_file)) {
+    error_log("Mail templates for '" . $lang . "' not found. Fallback to 'de-de'");
+    $lang = "de-de";
+}
+$lang_file = __DIR__ . "/lang/mail." . $lang . ".php";
+require_once($lang_file);
+unset($lang_file);
+?>

public/index.php

@@ -0,0 +1,258 @@
+<html><head><?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+// enforce admin via https
+if (!isset($_SERVER['HTTPS'])) {
+    header('Location: https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'], true, 301);
+    exit();
+}
+
+require_once(__DIR__ . "/../language.php");
+if (!file_exists("../config.php")) {
+    print($language["NO_CONFIGURATION"]);
+    exit();
+}
+require_once(__DIR__ . "/../config.php");
+
+// this values will not be used when using the register operation type
+$storeFirstLastName = false;
+if (isset($config["operationMode"]) && $config["operationMode"] === "local") {
+    $storeFirstLastName = true;
+}
+
+// currently the case to store the password on our own is the only supported one
+$storePassword = false;
+if (isset($config["getPasswordOnRegistration"]) && $config["getPasswordOnRegistration"] &&
+        isset($config["operationMode"]) && $config["operationMode"] === "synapse") {
+    $storePassword = true;
+}
+session_start();
+
+if ($_SERVER["REQUEST_METHOD"] == "POST") {
+    try {
+        if (!isset($_SESSION["token"]) || !isset($_POST["token"]) || $_SESSION["token"] != $_POST["token"]) {
+            // token not present or invalid
+            throw new Exception("UNKNOWN_SESSION");
+        }
+        if (!isset($_POST["username"])) {
+            throw new Exception("UNKNOWN_USERNAME");
+        }
+        if (strlen($_POST["username"]) > 20 ||
+                strlen($_POST["username"]) < 3 ||
+                !ctype_lower($_POST["username"])) {
+            throw new Exception("USERNAME_INVALID");
+        }
+        if (ctype_alnum($_POST['username']) != true) {
+            throw new Exception("USERNAME_NOT_ALNUM");
+        }
+        if ($storePassword && (!isset($_POST["password"]) || !isset($_POST["password_confirm"]))) {
+                throw new Exception("PASSWORD_NOT_PROVIDED");
+        }
+        if ($storePassword && $_POST["password"] != $_POST["password_confirm"]) {
+            throw new Exception("PASSWORD_NOT_MATCH");
+        }
+        if (isset($_POST["note"]) && strlen($_POST["note"]) > 50) {
+            throw new Exception("NOTE_LENGTH_EXEEDED");
+        }
+        if (!isset($_POST["email"]) || !filter_var($_POST["email"], FILTER_VALIDATE_EMAIL)) {
+            throw new Exception("EMAIL_INVALID_FORMAT");
+        }
+        if ($storeFirstLastName) {
+            // only require first_name and last_name when we will evaluate them
+            if (!isset($_POST["first_name"]) || !preg_match("/[A-Z][a-z]+/", $_POST["first_name"])) {
+                throw new Exception("FIRSTNAME_INVALID_FORMAT");
+            }
+            if (!isset($_POST["last_name"]) || !preg_match("/[A-Z][a-z]+/", $_POST["last_name"])) {
+                throw new Exception("SIRNAME_INVALID_FORMAT");
+            }
+            $first_name = filter_var($_POST["first_name"], FILTER_SANITIZE_STRING);
+            $last_name = filter_var($_POST["last_name"], FILTER_SANITIZE_STRING);
+        } else {
+            $first_name = $last_name = "";
+        }
+
+        $username = filter_var($_POST["username"], FILTER_SANITIZE_STRING);
+        $password = "";
+        if ($storePassword && isset($_POST["password"])) {
+            $password = filter_var($_POST["password"], FILTER_SANITIZE_STRING);
+        }
+        $note = filter_var($_POST["note"], FILTER_SANITIZE_STRING);
+        $email = filter_var($_POST["email"], FILTER_VALIDATE_EMAIL);
+
+        require_once(__DIR__ . "/../database.php");
+        $res = $mx_db->addRegistration($first_name, $last_name, $username, $password, $note, $email);
+
+        if (!isset($res["verify_token"])) {
+            error_log("sth. went wrong. registration did not throw but admin_token not set");
+            throw Exception("UNKNOWN_ERROR");
+        }
+        $verify_token = $res["verify_token"];
+
+        $verify_url = $config["webroot"] . "/verify.php?t=" . $verify_token;
+        require_once(__DIR__ . "/../mail_templates.php");
+        $success = send_mail_pending_verification(
+                $config["homeserver"], $storeFirstLastName ? $first_name . " " . $last_name : $username, $email, $verify_url);
+
+        $mx_db->setRegistrationStateVerify(
+                ($success ? RegisterState::PendingEmailVerify : RegisterState::PendingEmailSend), $verify_token);
+
+        print("<title>" . $language["SUCCESS"] . "</title>");
+        print("</head><body>");
+        print("<h1>" . $language["SUCCESS"] . "</h1>");
+        print("<p>" . $language["TASK_CHECK_YOUR_EMAIL_VERIFY"] . "</p>");
+        print("<a href=\"" . $config["webroot"] . "/index.php" . "\">" . $language["JUMP_TO_HOMEPAGE"] . "</a>");
+    } catch (Exception $e) {
+        print("<title>" . $language["REGISTRATION_REQUEST_FAILED"] . "</title>");
+        print("</head><body>");
+        print("<h1>" . $language["REGISTRATION_REQUEST_FAILED"] . "</h1>");
+        if (isset($language[$e->getMessage()])) {
+            print("<p>" . $language[$e->getMessage()] . "</p>");
+        } else {
+            print("<p>" . $e->getMessage() . "</p>");
+        }
+        print("<a href=\"" . $config["webroot"] . "/index.php" . "\">" . $language["JUMP_TO_HOMEPAGE"] . "</a>");
+    }
+} else {
+    $_SESSION["token"] = bin2hex(random_bytes(16));
+    ?>
+    <title><?php echo strtr($language["TOPIC_PLEASE_REGISTER"], ["@homeserver" => $config["homeserver"]]); ?></title>
+    <link href="//netdna.bootstrapcdn.com/bootstrap/3.1.0/css/bootstrap.min.css" rel="stylesheet">
+    <style>
+        body{
+            background-color: #525252;
+        }
+        .centered-form{
+            margin-top: 60px;
+        }
+
+        .centered-form .panel{
+            background: rgba(255, 255, 255, 0.8);
+            box-shadow: rgba(0, 0, 0, 0.3) 20px 20px 20px;
+        }
+    </style>
+    <script type="text/javascript" src="//code.jquery.com/jquery-1.11.1.min.js"></script>
+    <script type="text/javascript" src="//netdna.bootstrapcdn.com/bootstrap/3.1.0/js/bootstrap.min.js"></script>
+</head>
+<body>
+    <div class="container">
+        <div class="row centered-form">
+            <div class="col-xs-12 col-sm-8 col-md-4 col-sm-offset-2 col-md-offset-4">
+                <div class="panel panel-default">
+                    <div class="panel-heading">
+                        <h3 class="panel-title"><?php
+                            echo strtr($language["TOPIC_PLEASE_REGISTER"], ["@homeserver" => $config["homeserver"]])
+                            . "<small>" . $language["TOPIC_PLEASE_REGISTER_NOTE"] . "</small>";
+                            ?></h3>
+                    </div>
+                    <div class="panel-body">
+                        <form name="regForm" role="form" action="index.php" method="post">
+                            <?php if ($storeFirstLastName) { ?>
+                                <div class="row">
+                                    <div class="col-xs-6 col-sm-6 col-md-6">
+                                        <div class="form-group">
+                                            <input type="text" name="first_name" id="first_name" class="form-control input-sm"
+                                                   placeholder="<?php echo $language["FIRST_NAME"]; ?>" pattern="[A-Z][a-z]+">
+                                        </div>
+                                    </div>
+                                    <div class="col-xs-6 col-sm-6 col-md-6">
+                                        <div class="form-group">
+                                            <input type="text" name="last_name" id="last_name" class="form-control input-sm"
+                                                   placeholder="<?php echo $language["LAST_NAME"]; ?>" pattern="[A-Z][a-z]+">
+                                        </div>
+                                    </div>
+                                </div>
+                            <?php } ?>
+
+                            <div class="form-group">
+                                <input type="email" name="email" id="email" class="form-control input-sm" placeholder="<?php echo $language["EMAIL_ADDRESS"]; ?>" required>
+                            </div>
+
+                            <div class="form-group">
+                                <input type="text" name="note" id="note" class="form-control input-sm" placeholder="<?php echo $language["PLACEHOLDER_NOTE_ABOUT_YOURSELF"]; ?>">
+                            </div>
+
+                            <div class="form-group">
+                                <input type="text" name="username" id="username" class="form-control input-sm"
+                                       placeholder="<?php echo $language["USERNAME"]; ?>" pattern="[a-z1-9]{3,20}" required>
+                            </div>
+                            <?php if ($storePassword) { ?>
+                                <div class="row">
+                                    <div class="col-xs-6 col-sm-6 col-md-6">
+                                        <div class="form-group">
+                                            <input type="password" name="password" id="password" class="form-control input-sm" placeholder="<?php echo $language["PASSWORD"]; ?>" required>
+                                        </div>
+                                    </div>
+                                    <div class="col-xs-6 col-sm-6 col-md-6">
+                                        <div class="form-group">
+                                            <input type="password" name="password_confirm" id="password_confirm" class="form-control input-sm" placeholder="<?php echo $language["PASSWORD_CONFIRM"]; ?>" required>
+                                        </div>
+                                    </div>
+                                </div>
+                            <?php } ?>
+                            <input type="hidden" name="token" id="token" value="<?php echo $_SESSION["token"]; ?>">
+                            <input type="submit" value="<?php echo $language["REGISTER"]; ?>" class="btn btn-info btn-block">
+
+                        </form>
+                        <?php
+                        if (isset($language["NOTE_FOR_REGISTRATION"])) {
+                            echo "<p>" . $language["NOTE"] . ": <br />";
+                            echo strtr($language["NOTE_FOR_REGISTRATION"], ["@homeserver" => $config["homeserver"]]);
+                            echo "</p>";
+                        }
+                        ?>
+                    </div>
+                </div>
+            </div>
+        </div>
+    </div>
+    <script type="text/javascript">
+        var user_name = document.getElementById("username");
+        user_name.oninvalid = function (event) {
+            event.target.setCustomValidity("<?php echo $language["USERNAME_INVALID"]; ?>");
+        }
+        user_name.onkeyup = function (event) {
+            event.target.setCustomValidity("");
+        }
+<?php if ($storeFirstLastName) { ?>
+            var first_name = document.getElementById("first_name");
+            first_name.oninvalid = function (event) {
+                event.target.setCustomValidity("<?php echo $language["FIRSTNAME_INVALID_FORMAT"]; ?>");
+            }
+            first_name.onkeyup = function (event) {
+                event.target.setCustomValidity("");
+            }
+            var last_name = document.getElementById("last_name");
+            last_name.oninvalid = function (event) {
+                event.target.setCustomValidity("<?php echo $language["SIRNAME_INVALID_FORMAT"]; ?>");
+            }
+            last_name.onkeyup = function (event) {
+                event.target.setCustomValidity("");
+            }
+<?php } if ($storePassword) { ?>
+            var password = document.getElementById("password")
+                    , confirm_password = document.getElementById("password_confirm");
+            function validatePassword() {
+                if (password.value != confirm_password.value) {
+                    confirm_password.setCustomValidity("<?php echo $language["PASSWORD_NOT_MATCH"]; ?>");
+                } else {
+                    confirm_password.setCustomValidity('');
+                }
+            }
+            password.onchange = validatePassword;
+            confirm_password.onkeyup = validatePassword;
+<?php } ?>
+    </script>
+<?php } ?>
+</body></html>

public/verify.php

@@ -0,0 +1,99 @@
+<html><head><?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/../language.php");
+if (!file_exists("../config.php")) {
+    print($language["NO_CONFIGURATION"]);
+    exit();
+}
+require_once(__DIR__ . "/../config.php");
+require_once(__DIR__ . "/../mail_templates.php");
+
+// enforce admin via https
+if (!isset($_SERVER['HTTPS'])) {
+    header('Location: https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'], true, 301);
+    exit();
+}
+
+session_start();
+
+try {
+    if ($_SERVER["REQUEST_METHOD"] != "GET") {
+        throw new Exception("Method not allowed");
+    }
+    if (!isset($_GET["t"])) {
+        throw new Exception("UNKNOWN_TOKEN");
+    }
+    $token = filter_var($_GET["t"], FILTER_SANITIZE_STRING);
+
+    require_once(__DIR__ . "/../database.php");
+
+    $user = $mx_db->getUserForVerify($token);
+    if ($user == NULL) {
+        throw new Exception("UNKNOWN_TOKEN");
+    }
+    $first_name = $user["first_name"];
+    $last_name = $user["last_name"];
+    $username = $user["username"];
+    $note = $user["note"];
+    $email = $user["email"];
+    $admin_token = $user["admin_token"];
+
+    require_once(__DIR__ . "/../MatrixConnection.php");
+    $adminUrl = $config["webroot"] . "/verify_admin.php?t=" . $admin_token;
+    $mxConn = new MatrixConnection($config["homeserver"], $config["access_token"]);
+    $mxMsg = new MatrixMessage();
+    $mxMsg->set_body(strtr($language["MSG_USER_WANTS_REGISTER"], [
+        "@name" => (strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username),
+        "@note" => $note,
+        "@adminUrl" => $adminUrl
+    ]));
+    if (isset($language["MSG_USER_WANTS_REGISTER_FORMATTED"])) {
+        $mxMsg->set_formatted_body(strtr($language["MSG_USER_WANTS_REGISTER_FORMATTED"], [
+            "@name" => (strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username),
+            "@note" => $note,
+            "@adminUrl" => $adminUrl
+        ]));
+    }
+    $mxMsg->set_type("m.text");
+    $response = $mxConn->send($config["register_room"], $mxMsg);
+
+    if ($response) {
+        $message = $language["SEND_MATRIX_FAIL"];
+    }
+    $mx_db->setRegistrationStateVerify(
+            ($response ? RegisterState::PendingAdminVerify : RegisterState::PendingAdminSend), $token);
+
+    send_mail_pending_approval($config["homeserver"], $first_name . " " . $last_name, $email);
+
+    print("<title>" . $language["VERIFICATION_SUCEEDED"] . "</title>");
+    print("</head><body>");
+    print("<h1>" . $language["VERIFICATION_SUCEEDED"] . "</h1>");
+    print("<p>" . $language["VERIFICATION_SUCCESS_BODY"] . "</p>");
+    print("<a href=\"" . $config["webroot"] . "/index.php" . "\">" . $language["JUMP_TO_HOMEPAGE"] . "</a>");
+} catch (Exception $e) {
+    print("<title>" . $language["VERIFICATION_FAILED"] . "</title>");
+    print("</head><body>");
+    print("<h1>" . $language["VERIFICATION_FAILED"] . "</h1>");
+    if (isset($language[$e->getMessage()])) {
+        print("<p>" . $language[$e->getMessage()] . "</p>");
+    } else {
+        print("<p>" . $e->getMessage() . "</p>");
+    }
+    print("<a href=\"" . $config["webroot"] . "/index.php" . "\">" . $language["JUMP_TO_HOMEPAGE"] . "</a>");
+}
+?>
+    </body>
+</html>

public/verify_admin.php

@@ -0,0 +1,222 @@
+<html><head><?php
+/**
+ * Copyright 2018 Matthias Kesler
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+require_once(__DIR__ . "/../language.php");
+if (!file_exists("../config.php")) {
+    print($language["NO_CONFIGURATION"]);
+    exit();
+}
+require_once(__DIR__ . "/../config.php");
+require_once(__DIR__ . "/../mail_templates.php");
+
+// enforce admin via https
+if (!isset($_SERVER['HTTPS'])) {
+    header('Location: https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'], true, 301);
+    exit();
+}
+
+session_start();
+
+try {
+    if ($_SERVER["REQUEST_METHOD"] != "GET") {
+        throw new Exception("Method not allowed");
+    }
+    if (!isset($_GET["t"])) {
+        throw new Exception("UNKNOWN_TOKEN");
+    }
+    $token = filter_var($_GET["t"], FILTER_SANITIZE_STRING);
+
+    require_once(__DIR__ . "/../database.php");
+
+    $action = NULL;
+    if (isset($_GET["allow"])) {
+        $action = RegisterState::RegistrationAccepted;
+    }
+    $decline_reason = NULL;
+    if (isset($_GET["deny"])) {
+        $action = RegisterState::RegistrationDeclined;
+        if (isset($_GET["reason"])) {
+            $decline_reason = filter_var($_GET["reason"], FILTER_SANITIZE_STRING);
+        }
+    }
+
+    $user = $mx_db->getUserForApproval($token);
+    if ($user == NULL) {
+        throw new Exception("UNKNOWN_TOKEN");
+    }
+
+    $first_name = $user["first_name"];
+    $last_name = $user["last_name"];
+    $username = $user["username"];
+    $note = $user["note"];
+    $email = $user["email"];
+
+    if ($action == RegisterState::RegistrationAccepted) {
+        $mx_db->setRegistrationStateAdmin(RegisterState::PendingRegistration, $token);
+
+        // register user
+        require_once(__DIR__ . "/../MatrixConnection.php");
+        $mxConn = new MatrixConnection($config["homeserver"], $config["access_token"]);
+
+        $password = NULL;
+        $use_db_password = (isset($config["getPasswordOnRegistration"]) && $config["getPasswordOnRegistration"]);
+        if ($use_db_password && isset($user["password"]) && strlen($user["password"]) > 0) {
+            $password = $user["password"];
+        } else {
+            $use_db_password = false;
+            // generate a password with 10 characters
+            $password = bin2hex(openssl_random_pseudo_bytes(5));
+        }
+        switch ($config["operationMode"]) {
+            case "synapse":
+                // register with registration_shared_secret
+                $res = $mxConn->register($username, $password, $config["registration_shared_secret"]);
+                if (!$res) {
+                    // something went wrong while registering
+                    $password = NULL;
+                }
+                break;
+            case "local":
+                // register by adding a user to the local database
+                $password = $mx_db->addUser($first_name, $last_name, $username, $password, $email);
+                break;
+            default:
+                throw new Exception("Unknown operationMode");
+        }
+        if ($password != NULL) {
+            // send registration_success
+            $res = send_mail_registration_success(
+                    $config["homeserver"],
+                    $first_name . " " . $last_name,
+                    $email,
+                    $username,
+                    // only send password when auto-created
+                    ($use_db_password ? NULL : $password),
+                    $config["howToURL"]
+            );
+            if ($res) {
+                $mx_db->setRegistrationStateAdmin(RegisterState::AllDone, $token);
+            } else {
+                $mx_db->setRegistrationStateAdmin(RegisterState::PendingSendRegistrationMail, $token);
+            }
+        } else {
+            send_mail_registration_allowed_but_failed($config["homeserver"], $first_name . " " . $last_name, $email);
+            $mxMsg = new MatrixMessage();
+            $mxMsg->set_type("m.text");
+            $mxMsg->set_body(strtr($language["REGISTRATION_FAILED_FOR"], [
+                "@name" => strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username,
+            ]));
+            $mxConn->send($config["register_room"], $mxMsg);
+            throw new Exception("REGISTRATION_FAILED");
+        }
+
+        print("<title>" . $language["ADMIN_VERIFY_SITE_TITLE"] . "</title>");
+        print("</head><body>");
+        print("<h1>" . $language["ADMIN_VERIFY_SITE_TITLE"] . "</h1>");
+        print("<p>" . $language["ADMIN_REGISTER_ACCEPTED_BODY"] . "</p>");
+    } elseif ($action == RegisterState::RegistrationDeclined) {
+        $mx_db->setRegistrationStateAdmin(RegisterState::RegistrationDeclined, $token);
+        send_mail_registration_decline(
+                $config["homeserver"], strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username, $email, $decline_reason
+        );
+        print("<title>" . $language["ADMIN_VERIFY_SITE_TITLE"] . "</title>");
+        print("</head><body>");
+        print("<h1>" . $language["ADMIN_VERIFY_SITE_TITLE"] . "</h1>");
+        print("<p>" . $language["ADMIN_REGISTER_DECLINED_BODY"] . "</p>");
+    } else {
+
+        print("<title>" . $language["ADMIN_VERIFY_SITE_TITLE"] . "</title>");
+        ?>
+        <link href="//netdna.bootstrapcdn.com/bootstrap/3.1.0/css/bootstrap.min.css" rel="stylesheet">
+        <style>
+            body{
+                background-color: #525252;
+            }
+            .centered-form{
+                margin-top: 60px;
+            }
+
+            .centered-form .panel{
+                background: rgba(255, 255, 255, 0.8);
+                box-shadow: rgba(0, 0, 0, 0.3) 20px 20px 20px;
+            }
+        </style>
+        <script type="text/javascript" src="//code.jquery.com/jquery-1.11.1.min.js"></script>
+        <script type="text/javascript" src="//netdna.bootstrapcdn.com/bootstrap/3.1.0/js/bootstrap.min.js"></script>
+    </head>
+    <body>
+        <div class="container">
+            <div class="row centered-form">
+                <div class="col-xs-12 col-sm-8 col-md-4 col-sm-offset-2 col-md-offset-4">
+                    <div class="panel panel-default">
+                        <div class="panel-heading">
+                            <h3 class="panel-title"><?php echo $language["ADMIN_VERIFY_SITE_TITLE"]; ?></h3>
+                        </div>
+                        <div class="panel-body">
+                            <form name="appForm" role="form" action="verify_admin.php" method="GET">
+                                <?php
+                                if (isset($config["operationMode"]) && $config["operationMode"] === "local") {
+                                    // this values will not be used when using the register operation type
+                                    ?>
+                                    <div class="row">
+                                        <div class="col-xs-6 col-sm-6 col-md-6">
+                                            <div class="form-group">
+                                                <input type="text" id="first_name" class="form-control input-sm"
+                                                       value="<?php echo $first_name; ?>" disabled=true>
+                                            </div>
+                                        </div>
+                                        <div class="col-xs-6 col-sm-6 col-md-6">
+                                            <div class="form-group">
+                                                <input type="text" id="last_name" class="form-control input-sm"
+                                                       value="<?php echo $last_name; ?>" disabled=true>
+                                            </div>
+                                        </div>
+                                    </div>
+                                <?php } ?>
+                                <div class="form-group">
+                                    <input type="text" id="note" class="form-control input-sm" value="<?php echo $note; ?>" disabled=true>
+                                </div>
+
+                                <div class="form-group">
+                                    <input type="text" id="username" class="form-control input-sm"
+                                           value="<?php echo $username; ?>" disabled=true>
+                                </div>
+                                <input type="hidden" name="t" id="token" value="<?php echo $token; ?>">
+                                <input type="submit" name="allow" value="<?php echo $language["ACCEPT"]; ?>" class="btn btn-info btn-block">
+                                <input type="submit" name="deny" value="<?php echo $language["DECLINE"]; ?>" class="btn btn-info btn-block">
+                            </form>
+                        </div>
+                    </div>
+                </div>
+            </div>
+        </div>
+        <script type="text/javascript">
+
+            <?php
+        } // else - no action provided
+    } catch (Exception $e) {
+        print("<title>" . $language["REGISTRATION_FAILED"] . "</title>");
+        print("</head><body>");
+        print("<h1>" . $language["REGISTRATION_FAILED"] . "</h1>");
+        if (isset($language[$e->getMessage()])) {
+            print("<p>" . $language[$e->getMessage()] . "</p>");
+        } else {
+            print("<p>" . $e->getMessage() . "</p>");
+        }
+        print("<a href=\"" . $config["webroot"] . "/index.php" . "\">" . $language["JUMP_TO_HOMEPAGE"] . "</a>");
+    }
+    ?>
+    </body>
+</html>