<?php

define('NO_AUTH_REQUIRED', true);
// Main include

include($_SERVER['DOCUMENT_ROOT'] . '/inc/main.php');

$TAB = 'login';


if (isset($_GET['logout'])) {
    unset($_SESSION);
    session_unset();
    session_destroy();
    header('Location: /login/');
}

/* ACTIONS FOR CURRENT USER SESSION */
if (isset($_SESSION['user'])) {

    // User impersonation
    // Allow administrators to view and manipulate contents of other user accounts
    if (($_SESSION['userContext'] === 'admin') && (!empty($_GET['loginas']))) {
        // Ensure token is passed and matches before granting user impersonation access
        if (verify_csrf($_GET)) {
            $v_user = escapeshellarg($_GET['loginas']);
            $v_impersonator = escapeshellarg($_SESSION['user']);
            exec(HESTIA_CMD . "v-list-user ".$v_user." json", $output, $return_var);
            if ($return_var == 0) {
                $data = json_decode(implode('', $output), true);
                reset($data);
                $_SESSION['look'] = key($data);
                // Log impersonation events
                exec(HESTIA_CMD . 'v-log-action ' . $v_impersonator . " 'Info' 'Security' 'Logged in as another user (User: $v_user)'", $output, $return_var);
                exec(HESTIA_CMD . "v-log-action system 'Warning' 'Security' 'User impersonation session started (User: $v_user, Administrator: $v_impersonator)'", $output, $return_var);
                // Reset account details for File Manager to impersonated user
                unset($_SESSION['_sf2_attributes']);
                unset($_SESSION['_sf2_meta']);
                header('Location: /login/');
            } else {
                # User doesn't exists
                header('Location: /');
            }
        }
        exit;
    }

    // Set view based on account properties
    if (empty($_GET['loginas'])) {
        // Default view to Users list for administrator accounts
        if (($_SESSION['userContext'] === 'admin') && (!isset($_SESSION['look']))) {
            header('Location: /list/user/');
            exit;
        }

        // Obtain account properties
        $v_user = escapeshellarg($_SESSION[(($_SESSION['userContext'] === 'admin') && (isset($_SESSION['look']))) ? 'look' : 'user']);

        exec(HESTIA_CMD . 'v-list-user ' . $v_user . ' json', $output, $return_var);
        $data = json_decode(implode('', $output), true);
        unset($output);

        // Determine package features and land user at the first available page
        if ($data[$user_plain]['WEB_DOMAINS'] !== '0') {
            header('Location: /list/web/');
        } elseif ($data[$user_plain]['DNS_DOMAINS'] !== '0') {
            header('Location: /list/dns/');
        } elseif ($data[$user_plain]['MAIL_DOMAINS'] !== '0') {
            header('Location: /list/mail/');
        } elseif ($data[$user_plain]['DATABASES'] !== '0') {
            header('Location: /list/db/');
        } elseif ($data[$user_plain]['CRON_JOBS'] !== '0') {
            header('Location: /list/cron/');
        } elseif ($data[$user_plain]['BACKUPS'] !== '0') {
            header('Location: /list/backup/');
        } else {
            header('Location: /error/');
        }
        exit;
    }

    // Do not allow non-administrators to access account impersonation
    if (($_SESSION['userContext'] !== 'admin') && (!empty($_GET['loginas']))) {
        header('Location: /login/');
        exit;
    }

    exit;
}

function authenticate_user($user, $password, $twofa = '')
{
    unset($_SESSION['login']);
    if (verify_csrf($_POST, true)) {
        $v_user = escapeshellarg($user);
        $ip = $_SERVER['REMOTE_ADDR'];
        $user_agent = $_SERVER['HTTP_USER_AGENT'];
        if (isset($_SERVER['HTTP_CF_CONNECTING_IP'])) {
            if (!empty($_SERVER['HTTP_CF_CONNECTING_IP'])) {
                $ip = $_SERVER['HTTP_CF_CONNECTING_IP'];
            }
        }
        $v_ip = escapeshellarg($ip);
        $v_user_agent = escapeshellarg($user_agent);

        // Get user's salt
        $output = '';
        exec(HESTIA_CMD . 'v-get-user-salt ' . $v_user . ' ' . $v_ip . ' json', $output, $return_var);
        $pam = json_decode(implode('', $output), true);
        unset($output);
        if ($return_var > 0) {
            sleep(2);
            if ($return_var == 5) {
                $error = '<a class="error">' . _('Account has been suspended') . '</a>';
            } elseif ($return_var == 1) {
                $error = '<a class="error">' . _('Unsupported hash method') . '</a>';
            } else {
                $error = '<a class="error">' . _('Invalid username or password') . '</a>';
            }
            return $error;
        } else {
            $salt = $pam[$user]['SALT'];
            $method = $pam[$user]['METHOD'];

            if ($method == 'md5') {
                $hash = crypt($password, '$1$' . $salt . '$');
            }
            if ($method == 'sha-512') {
                $hash = crypt($password, '$6$rounds=5000$' . $salt . '$');
                $hash = str_replace('$rounds=5000', '', $hash);
            }
            if ($method == 'yescrypt') {
                $v_password = tempnam("/tmp", "vst");
                $fp = fopen($v_password, "w");
                fwrite($fp, $password."\n");
                fclose($fp);
                exec(HESTIA_CMD . 'v-check-user-password '. $v_user.' '. $v_password. ' '.$v_ip.' yes', $output, $return_var);
                $hash = $output[0];
                unset($output);
            }
            if ($method == 'des') {
                $hash = crypt($password, $salt);
            }

            // Send hash via tmp file
            $v_hash = exec('mktemp -p /tmp');
            $fp = fopen($v_hash, 'w');
            fwrite($fp, $hash."\n");
            fclose($fp);

            // Check user hash
            exec(HESTIA_CMD . 'v-check-user-hash ' . $v_user . ' ' . $v_hash . ' ' . $v_ip, $output, $return_var);
            unset($output);

            // Remove tmp file
            unlink($v_hash);
            // Check API answer
            if ($return_var > 0) {
                sleep(2);
                $error = '<a class="error">' . _('Invalid username or password') . '</a>';
                $v_session_id = escapeshellarg($_POST['token']);
                exec(HESTIA_CMD . 'v-log-user-login ' . $v_user . ' ' . $v_ip . ' failed ' . $v_session_id . ' ' . $v_user_agent, $output, $return_var);
                return $error;
            } else {

                // Get user specific parameters
                exec(HESTIA_CMD . 'v-list-user ' . $v_user . ' json', $output, $return_var);
                $data = json_decode(implode('', $output), true);
                unset($output);
                if ($data[$user]['LOGIN_DISABLED'] === 'yes') {
                    sleep(2);
                    $error = '<a class="error">' . _('Invalid username or password') . '</a>';
                    $v_session_id = escapeshellarg($_POST['token']);
                    exec(HESTIA_CMD . 'v-log-user-login ' . $v_user . ' ' . $v_ip . ' failed ' . $v_session_id . ' ' . $v_user_agent .' yes "Login disabled for this user"', $output, $return_var);
                    return $error;
                }

                if ($data[$user]['LOGIN_USE_IPLIST'] === 'yes') {
                    $v_login_user_allowed_ips = explode(',', $data[$user]['LOGIN_ALLOW_IPS']);
                    $v_login_user_allowed_ips = array_map('trim', $v_login_user_allowed_ips);
                    if (!in_array($ip, $v_login_user_allowed_ips, true)) {
                        sleep(2);
                        $error = '<a class="error">' . _('Invalid username or password') . '</a>';
                        $v_session_id = escapeshellarg($_POST['token']);
                        exec(HESTIA_CMD . 'v-log-user-login ' . $v_user . ' ' . $v_ip . ' failed ' . $v_session_id . ' ' . $v_user_agent .' yes "Ip not in allowed list"', $output, $return_var);
                        return $error;
                    }
                }

                if ($data[$user]['TWOFA'] != '') {
                    exec(HESTIA_CMD . "v-check-user-2fa " . $v_user . " " . $v_twofa, $output, $return_var);
                    $error = "<a class=\"error\">" . _('Invalid or missing 2FA token') . "</a>";
                    if (empty($twofa)) {
                        $_SESSION['login']['username'] = $user;
                        $_SESSION['login']['password'] = $password;
                        return false;
                    } else {
                        $v_twofa = escapeshellarg($twofa);
                        exec(HESTIA_CMD .'v-check-user-2fa '.$v_user.' '.$v_twofa, $output, $return_var);
                        unset($output);
                        if ($return_var > 0) {
                            sleep(2);
                            $error = '<a class="error">' ._('Invalid or missing 2FA token') . '</a>';
                            $_SESSION['login']['username'] = $user;
                            $_SESSION['login']['password'] = $password;
                            $v_session_id = escapeshellarg($_POST['token']);
                            if (isset($_SESSION['failed_twofa'])) {
                                //allow a few failed attemps before start of logging.
                                if ($_SESSION['failed_twofa']  > 2) {
                                    exec(HESTIA_CMD.'v-log-user-login ' . $v_user . ' ' . $v_ip . ' failed ' . $v_session_id . ' ' . $v_user_agent .' yes "Invalid or missing 2FA token"', $output, $return_var);
                                }
                                $_SESSION['failed_twofa']++;
                            } else {
                                $_SESSION['failed_twofa'] = 1;
                            }
                            unset($_POST['twofa']);
                            return $error;
                        }
                    }
                }

                // Define session user
                $_SESSION['user'] = key($data);
                $v_user = $_SESSION['user'];
                //log successfull login attempt
                $v_session_id = escapeshellarg($_POST['token']);
                exec(HESTIA_CMD."v-log-user-login ".$v_user." ".$v_ip." success ".$v_session_id." ".$v_user_agent, $output, $return_var);

                $_SESSION['LAST_ACTIVITY'] = time();
                $_SESSION['MURMUR'] = $_POST['murmur'];

                // Define user role / context
                $_SESSION['userContext'] = $data[$user]['ROLE'];

                // Set active user theme on login
                $_SESSION['userTheme'] = $data[$user]['THEME'];
                if ($_SESSION['POLICY_USER_CHANGE_THEME'] !== 'yes') {
                    unset($_SESSION['userTheme']);
                }

                $_SESSION['userSortOrder'] = (!empty($data[$user]['PREF_UI_SORT'])) ? $data[$user]['PREF_UI_SORT'] : 'name';

                // Define language
                $output = '';
                exec(HESTIA_CMD . 'v-list-sys-languages json', $output, $return_var);
                $languages = json_decode(implode('', $output), true);
                $_SESSION['language'] = (in_array($data[$v_user]['LANGUAGE'], $languages)) ? $data[$user]['LANGUAGE'] : 'en';

                // Regenerate session id to prevent session fixation
                session_regenerate_id(true);

                // Redirect request to control panel interface
                if (!empty($_SESSION['request_uri'])) {
                    header('Location: ' . $_SESSION['request_uri']);
                    unset($_SESSION['request_uri']);
                    exit;
                } else {
                    if ($_SESSION['userContext'] === 'admin') {
                        header('Location: /list/user/');
                    } else {
                        if ($data[$user]['WEB_DOMAINS'] != '0') {
                            header('Location: /list/web/');
                        } elseif ($data[$user]['DNS_DOMAINS'] != '0') {
                            header('Location: /list/dns/');
                        } elseif ($data[$user]['MAIL_DOMAINS'] != '0') {
                            header('Location: /list/mail/');
                        } elseif ($data[$user]['DATABASES'] != '0') {
                            header('Location: /list/db/');
                        } elseif ($data[$user]['CRON_JOBS'] != '0') {
                            header('Location: /list/cron/');
                        } elseif ($data[$user]['BACKUPS'] != '0') {
                            header('Location: /list/backup/');
                        } else {
                            header('Location: /error/');
                        }
                    }
                    exit;
                }
            }
        }
    } else {
        unset($_POST);
        unset($_GET);
        unset($_SESSION);
        // Delete old session and  start a new one
        session_write_close();
        session_unset();
        session_destroy();
        session_start();
        return false;
    }
}
if (empty($_POST['user'])) {
    $user = '';
} else {
    if (preg_match('/^[[:alnum:]][-|\.|_[:alnum:]]{0,28}[[:alnum:]]$/', $_POST['user'])) {
        $_SESSION['login']['username'] = $_POST['user'];
    } else {
        $user = '';
    }
}
if (!empty($_SESSION['login']['username']) && !empty($_SESSION['login']['password']) && !empty($_POST['twofa'])) {
    $error = authenticate_user($_SESSION['login']['username'], $_SESSION['login']['password'], $_POST['twofa']);
    unset($_POST);
} elseif (!empty($_SESSION['login']['username']) && !empty($_POST['password'])) {
    $error = authenticate_user($_SESSION['login']['username'], $_POST['password']);
    unset($_POST);
}
// Check system configuration
load_hestia_config();

// Detect language
if (empty($_SESSION['language'])) {
    $output = '';
    exec(HESTIA_CMD . 'v-list-sys-config json', $output, $return_var);
    $config = json_decode(implode('', $output), true);
    $lang = $config['config']['LANGUAGE'];

    $output = '';
    exec(HESTIA_CMD . 'v-list-sys-languages json', $output, $return_var);
    $languages = json_decode(implode('', $output), true);
    $_SESSION['language'] = (in_array($lang, $languages)) ? $lang : 'en';
}

// Generate CSRF token
$token = bin2hex(random_bytes(16));
$_SESSION['token'] = $token;

require_once('../templates/header.html');
if (!empty($_SESSION['login']['password'])) {
    require_once('../templates/pages/login/login_2.html');
} elseif (empty($_SESSION['login']['username'])) {
    require_once('../templates/pages/login/login' . (($_SESSION['LOGIN_STYLE'] != 'old') ? '' : '_a') . '.html');
} elseif (empty($_POST['password'])) {
    require_once('../templates/pages/login/login_1.html');
} else {
    require_once('../templates/pages/login/login' . (($_SESSION['LOGIN_STYLE'] != 'old') ? '' : '_a') . '.html');
}