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\System;
   9 use Friendica\Database\DBA;
  10 use Friendica\Model\Contact;
  11 use Friendica\Model\OpenWebAuthToken;
  12 use Friendica\Util\HTTPSignature;
  13
  14 /**
  15  * @brief OpenWebAuth verifier and token generator
  16  *
  17  * See https://macgirvin.com/wiki/mike/OpenWebAuth/Home
  18  * Requests to this endpoint should be signed using HTTP Signatures
  19  * using the 'Authorization: Signature' authentication method
  20  * If the signature verifies a token is returned.
  21  *
  22  * This token may be exchanged for an authenticated cookie.
  23  *
  24  * Ported from Hubzilla: https://framagit.org/hubzilla/core/blob/master/Zotlabs/Module/Owa.php
  25  */
  26 class Owa extends BaseModule
  27 {
  28         public static function init()
  29         {
  30
  31                 $ret = [ 'success' => false ];
  32
  33                 foreach (['REDIRECT_REMOTE_USER', 'HTTP_AUTHORIZATION'] as $head) {
  34                         if (array_key_exists($head, $_SERVER) && substr(trim($_SERVER[$head]), 0, 9) === 'Signature') {
  35                                 if ($head !== 'HTTP_AUTHORIZATION') {
  36                                         $_SERVER['HTTP_AUTHORIZATION'] = $_SERVER[$head];
  37                                         continue;
  38                                 }
  39
  40                                 $sigblock = HTTPSignature::parseSigheader($_SERVER[$head]);
  41                                 if ($sigblock) {
  42                                         $keyId = $sigblock['keyId'];
  43
  44                                         if ($keyId) {
  45                                                 // Try to find the public contact entry of the handle.
  46                                                 $handle = str_replace('acct:', '', $keyId);
  47
  48                                                 $cid       = Contact::getIdForURL($handle);
  49                                                 $fields    = ['id', 'url', 'addr', 'pubkey'];
  50                                                 $condition = ['id' => $cid];
  51
  52                                                 $contact = DBA::selectFirst('contact', $fields, $condition);
  53
  54                                                 if (DBA::isResult($contact)) {
  55                                                         // Try to verify the signed header with the public key of the contact record
  56                                                         // we have found.
  57                                                         $verified = HTTPSignature::verify('', $contact['pubkey']);
  58
  59                                                         if ($verified && $verified['header_signed'] && $verified['header_valid']) {
  60                                                                 logger('OWA header: ' . print_r($verified, true), LOGGER_DATA);
  61                                                                 logger('OWA success: ' . $contact['addr'], LOGGER_DATA);
  62
  63                                                                 $ret['success'] = true;
  64                                                                 $token = random_string(32);
  65
  66                                                                 // Store the generated token in the databe.
  67                                                                 OpenWebAuthToken::create('owt', 0, $token, $contact['addr']);
  68
  69                                                                 $result = '';
  70
  71                                                                 // Encrypt the token with the public contacts publik key.
  72                                                                 // Only the specific public contact will be able to encrypt it.
  73                                                                 // At a later time, we will compare weather the token we're getting
  74                                                                 // is really the same token we have stored in the database.
  75                                                                 openssl_public_encrypt($token, $result, $contact['pubkey']);
  76                                                                 $ret['encrypted_token'] = base64url_encode($result);
  77                                                         } else {
  78                                                                 logger('OWA fail: ' . $contact['id'] . ' ' . $contact['addr'] . ' ' . $contact['url'], LOGGER_DEBUG);
  79                                                         }
  80                                                 } else {
  81                                                         logger('Contact not found: ' . $handle, LOGGER_DEBUG);
  82                                                 }
  83                                         }
  84                                 }
  85                         }
  86                 }
  87                 System::jsonExit($ret, 'application/x-dfrn+json');
  88         }
  89 }