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\Database\DBM;
  11 use Friendica\Model\Contact;
  12 use Friendica\Model\OpenWebAuthToken;
  13 use Friendica\Util\HTTPSignature;
  14
  15 /**
  16  * @brief OpenWebAuth verifier and token generator
  17  *
  18  * See https://macgirvin.com/wiki/mike/OpenWebAuth/Home
  19  * Requests to this endpoint should be signed using HTTP Signatures
  20  * using the 'Authorization: Signature' authentication method
  21  * If the signature verifies a token is returned.
  22  *
  23  * This token may be exchanged for an authenticated cookie.
  24  *
  25  * Ported from Hubzilla: https://framagit.org/hubzilla/core/blob/master/Zotlabs/Module/Owa.php
  26  */
  27 class Owa extends BaseModule
  28 {
  29         public static function init()
  30         {
  31
  32                 $ret = [ 'success' => false ];
  33
  34                 foreach (['REDIRECT_REMOTE_USER', 'HTTP_AUTHORIZATION'] as $head) {
  35                         if (array_key_exists($head, $_SERVER) && substr(trim($_SERVER[$head]), 0, 9) === 'Signature') {
  36                                 if ($head !== 'HTTP_AUTHORIZATION') {
  37                                         $_SERVER['HTTP_AUTHORIZATION'] = $_SERVER[$head];
  38                                         continue;
  39                                 }
  40
  41                                 $sigblock = HTTPSignature::parseSigheader($_SERVER[$head]);
  42                                 if ($sigblock) {
  43                                         $keyId = $sigblock['keyId'];
  44
  45                                         if ($keyId) {
  46                                                 // Try to find the public contact entry of the handle.
  47                                                 $handle = str_replace('acct:', '', $keyId);
  48
  49                                                 $cid       = Contact::getIdForURL($handle);
  50                                                 $fields    = ['id', 'url', 'addr', 'pubkey'];
  51                                                 $condition = ['id' => $cid];
  52
  53                                                 $contact = DBA::selectFirst('contact', $fields, $condition);
  54
  55                                                 if (DBM::is_result($contact)) {
  56                                                         // Try to verify the signed header with the public key of the contact record
  57                                                         // we have found.
  58                                                         $verified = HTTPSignature::verify('', $contact['pubkey']);
  59
  60                                                         if ($verified && $verified['header_signed'] && $verified['header_valid']) {
  61                                                                 logger('OWA header: ' . print_r($verified, true), LOGGER_DATA);
  62                                                                 logger('OWA success: ' . $contact['addr'], LOGGER_DATA);
  63
  64                                                                 $ret['success'] = true;
  65                                                                 $token = random_string(32);
  66
  67                                                                 // Store the generated token in the databe.
  68                                                                 OpenWebAuthToken::create('owt', 0, $token, $contact['addr']);
  69
  70                                                                 $result = '';
  71
  72                                                                 // Encrypt the token with the public contacts publik key.
  73                                                                 // Only the specific public contact will be able to encrypt it.
  74                                                                 // At a later time, we will compare weather the token we're getting
  75                                                                 // is really the same token we have stored in the database.
  76                                                                 openssl_public_encrypt($token, $result, $contact['pubkey']);
  77                                                                 $ret['encrypted_token'] = base64url_encode($result);
  78                                                         } else {
  79                                                                 logger('OWA fail: ' . $contact['id'] . ' ' . $contact['addr'] . ' ' . $contact['url'], LOGGER_DEBUG);
  80                                                         }
  81                                                 } else {
  82                                                         logger('Contact not found: ' . $handle, LOGGER_DEBUG);
  83                                                 }
  84                                         }
  85                                 }
  86                         }
  87                 }
  88                 System::jsonExit($ret, 'application/x-dfrn+json');
  89         }
  90 }