src/Module/Owa.php

   1 <?php
   2 /**
   3  * @file src/Module/Owa.php
   4  */
   5 namespace Friendica\Module;
   6
   7 use Friendica\BaseModule;
   8 use Friendica\Core\Logger;
   9 use Friendica\Core\System;
  10 use Friendica\Database\DBA;
  11 use Friendica\Model\Contact;
  12 use Friendica\Model\OpenWebAuthToken;
  13 use Friendica\Util\HTTPSignature;
  14 use Friendica\Util\Strings;
  15
  16 /**
  17  * @brief OpenWebAuth verifier and token generator
  18  *
  19  * See https://macgirvin.com/wiki/mike/OpenWebAuth/Home
  20  * Requests to this endpoint should be signed using HTTP Signatures
  21  * using the 'Authorization: Signature' authentication method
  22  * If the signature verifies a token is returned.
  23  *
  24  * This token may be exchanged for an authenticated cookie.
  25  *
  26  * Ported from Hubzilla: https://framagit.org/hubzilla/core/blob/master/Zotlabs/Module/Owa.php
  27  */
  28 class Owa extends BaseModule
  29 {
  30         public static function init()
  31         {
  32
  33                 $ret = [ 'success' => false ];
  34
  35                 foreach (['REDIRECT_REMOTE_USER', 'HTTP_AUTHORIZATION'] as $head) {
  36                         if (array_key_exists($head, $_SERVER) && substr(trim($_SERVER[$head]), 0, 9) === 'Signature') {
  37                                 if ($head !== 'HTTP_AUTHORIZATION') {
  38                                         $_SERVER['HTTP_AUTHORIZATION'] = $_SERVER[$head];
  39                                         continue;
  40                                 }
  41
  42                                 $sigblock = HTTPSignature::parseSigheader($_SERVER[$head]);
  43                                 if ($sigblock) {
  44                                         $keyId = $sigblock['keyId'];
  45
  46                                         if ($keyId) {
  47                                                 // Try to find the public contact entry of the handle.
  48                                                 $handle = str_replace('acct:', '', $keyId);
  49
  50                                                 $cid       = Contact::getIdForURL($handle);
  51                                                 $fields    = ['id', 'url', 'addr', 'pubkey'];
  52                                                 $condition = ['id' => $cid];
  53
  54                                                 $contact = DBA::selectFirst('contact', $fields, $condition);
  55
  56                                                 if (DBA::isResult($contact)) {
  57                                                         // Try to verify the signed header with the public key of the contact record
  58                                                         // we have found.
  59                                                         $verified = HTTPSignature::verifyMagic($contact['pubkey']);
  60
  61                                                         if ($verified && $verified['header_signed'] && $verified['header_valid']) {
  62                                                                 Logger::log('OWA header: ' . print_r($verified, true), Logger::DATA);
  63                                                                 Logger::log('OWA success: ' . $contact['addr'], Logger::DATA);
  64
  65                                                                 $ret['success'] = true;
  66                                                                 $token = Strings::getRandomHex(32);
  67
  68                                                                 // Store the generated token in the databe.
  69                                                                 OpenWebAuthToken::create('owt', 0, $token, $contact['addr']);
  70
  71                                                                 $result = '';
  72
  73                                                                 // Encrypt the token with the public contacts publik key.
  74                                                                 // Only the specific public contact will be able to encrypt it.
  75                                                                 // At a later time, we will compare weather the token we're getting
  76                                                                 // is really the same token we have stored in the database.
  77                                                                 openssl_public_encrypt($token, $result, $contact['pubkey']);
  78                                                                 $ret['encrypted_token'] = Strings::base64UrlEncode($result);
  79                                                         } else {
  80                                                                 Logger::log('OWA fail: ' . $contact['id'] . ' ' . $contact['addr'] . ' ' . $contact['url'], Logger::DEBUG);
  81                                                         }
  82                                                 } else {
  83                                                         Logger::log('Contact not found: ' . $handle, Logger::DEBUG);
  84                                                 }
  85                                         }
  86                                 }
  87                         }
  88                 }
  89                 System::jsonExit($ret, 'application/x-zot+json');
  90         }
  91 }