3 require_once('include/certfns.php');
5 function receive_return($val) {
9 if($val >= 200 && $val < 300)
12 logger('mod-diaspora returns ' . $val);
13 header($_SERVER["SERVER_PROTOCOL"] . ' ' . $val . ' ' . $err);
19 function get_diaspora_key($uri) {
22 logger('Fetching diaspora key for: ' . $uri);
28 if($a['@attributes']['rel'] === 'diaspora-public-key') {
29 $key = base64_decode($a['@attributes']['href']);
38 return rsatopem($key);
43 function diaspora_base_message($type,$data) {
45 $tpl = get_markup_template('diaspora_' . $type . '.tpl');
48 return replace_macros($tpl,$data);
53 function diaspora_msg_build($msg,$user,$contact,$prvkey,$pubkey) {
56 $inner_aes_key = random_string(32);
57 $b_inner_aes_key = base64_encode($inner_aes_key);
58 $inner_iv = random_string(32);
59 $b_inner_iv = base64_encode($inner_iv);
61 $outer_aes_key = random_string(32);
62 $b_outer_aes_key = base64_encode($outer_aes_key);
63 $outer_iv = random_string(32);
64 $b_outer_iv = base64_encode($outer_iv);
66 $handle = 'acct:' . $user['nickname'] . '@' . substr($a->get_baseurl(), strpos($a->get_baseurl(),'://') + 3);
68 $padded_data = pkcs5_pad($msg,16);
69 $inner_encrypted = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $inner_aes_key, $padded_data, MCRYPT_MODE_CBC, $inner_iv);
71 $b64_data = base64_encode($inner_encrypted);
74 $b64url_data = base64url_encode($b64_data);
75 $b64url_stripped = str_replace(array("\n","\r"," ","\t"),array('','','',''),$b64url_data);
76 $lines = str_split($b64url_stripped,60);
77 $data = implode("\n",$lines);
78 $data = $data . (($data[-1] != "\n") ? "\n" : '') ;
79 $type = 'application/atom+xml';
80 $encoding = 'base64url';
83 $signable_data = $data . '.' . base64url_encode($type) . "\n" . '.'
84 . base64url_encode($encoding) . "\n" . '.' . base64url_encode($alg) . "\n";
87 $result = openssl_sign($signable_data,$signature,$prvkey,'SHA256');
89 $sig = base64url_encode($signature);
91 $decrypted_header = <<< EOT
94 <aes_key>$b_inner_aes_key</aes_key>
96 <name>{$contact['name']}</name>
102 $decrypted_header = pkcs5_pad($decrypted_header,16);
104 $ciphertext = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $outer_aes_key, $decrypted_header, MCRYPT_MODE_CBC, $outer_iv);
106 $outer_json = json_encode(array('iv' => $b_outer_iv,'key' => $b_outer_aes_key));
107 $encrypted_outer_key_bundle = '';
108 openssl_public_encrypt($outer_json,$encrypted_outer_key_bundle,$pubkey);
110 $b64_encrypted_outer_key_bundle = base64_encode($encrypted_outer_key_bundle);
111 $encrypted_header_json_object = json_encode(array('aes_key' => base64_encode($encrypted_outer_key_bundle),
112 'ciphertext' => base64_encode($ciphertext)));
113 $encrypted_header = '<encrypted_header>' . base64_encode($encrypted_header_json_object) . '</encrypted_header>';
116 <?xml version='1.0' encoding='UTF-8'?>
117 <entry xmlns='http://www.w3.org/2005/Atom'>
119 <me:env xmlns:me="http://salmon-protocol.org/ns/magic-env">
120 <me:encoding>base64url</me:encoding>
121 <me:alg>RSA-SHA256</me:alg>
122 <me:data type="application/atom+xml">$data</me:data>
123 <me:sig>$sig</me:sig>
133 function diaspora_decode($importer,$xml) {
135 $basedom = parse_xml_string($xml);
137 $atom = $basedom->children(NAMESPACE_ATOM1);
139 $encrypted_header = json_decode(base64_decode($atom->encrypted_header));
141 $encrypted_aes_key_bundle = base64_decode($encrypted_header->aes_key);
142 $ciphertext = base64_decode($encrypted_header->ciphertext);
144 $outer_key_bundle = '';
145 openssl_private_decrypt($encrypted_aes_key_bundle,$outer_key_bundle,$importer['prvkey']);
147 $j_outer_key_bundle = json_decode($outer_key_bundle);
149 $outer_iv = base64_decode($j_outer_key_bundle->iv);
150 $outer_key = base64_decode($j_outer_key_bundle->key);
152 $decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $outer_key, $ciphertext, MCRYPT_MODE_CBC, $outer_iv);
154 $decrypted = pkcs5_unpad($decrypted);
157 * $decrypted now contains something like
160 * <iv>8e+G2+ET8l5BPuW0sVTnQw==</iv>
161 * <aes_key>UvSMb4puPeB14STkcDWq+4QE302Edu15oaprAQSkLKU=</aes_key>
163 * <name>Ryan Hughes</name>
164 * <uri>acct:galaxor@diaspora.pirateship.org</uri>
166 * </decrypted_header>
169 $idom = parse_xml_string($decrypted,false);
171 $inner_iv = base64_decode($idom->iv);
172 $inner_aes_key = base64_decode($idom->aes_key);
174 $author_link = str_replace('acct:','',$idom->author->uri);
176 $dom = $basedom->children(NAMESPACE_SALMON_ME);
178 // figure out where in the DOM tree our data is hiding
180 if($dom->provenance->data)
181 $base = $dom->provenance;
182 elseif($dom->env->data)
188 logger('mod-diaspora: unable to locate salmon data in xml ');
193 // Stash the signature away for now. We have to find their key or it won't be good for anything.
194 $signature = base64url_decode($base->sig);
198 // strip whitespace so our data element will return to one big base64 blob
199 $data = str_replace(array(" ","\t","\r","\n"),array("","","",""),$base->data);
200 // Add back the 60 char linefeeds
201 $lines = str_split($data,60);
202 $data = implode("\n",$lines);
205 // stash away some other stuff for later
207 $type = $base->data[0]->attributes()->type[0];
208 $keyhash = $base->sig[0]->attributes()->keyhash[0];
209 $encoding = $base->encoding;
212 $signed_data = $data . (($data[-1] != "\n") ? "\n" : '') . '.' . base64url_encode($type) . "\n" . '.' . base64url_encode($encoding) . "\n" . '.' . base64url_encode($alg) . "\n";
216 $data = base64url_decode($data);
218 // Now pull out the inner encrypted blob
220 $inner_encrypted = base64_decode($data);
223 $inner_decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $inner_aes_key, $inner_encrypted, MCRYPT_MODE_CBC, $inner_iv);
225 $inner_decrypted = pkcs5_unpad($inner_decrypted);
228 logger('mod-diaspora: Could not retrieve author URI.');
232 // Once we have the author URI, go to the web and try to find their public key
233 // *** or look it up locally ***
235 logger('mod-diaspora: Fetching key for ' . $author_link );
237 // Get diaspora public key (pkcs#1) and convert to pkcs#8
238 $key = get_diaspora_key($author_link);
241 logger('mod-diaspora: Could not retrieve author key.');
247 if (version_compare(PHP_VERSION, '5.3.0', '>=')) {
248 $verify = openssl_verify($signed_data,$signature,$key,'sha256');
251 // fallback sha256 verify for PHP < 5.3
253 $hash = hash('sha256',$signed_data,true);
254 openssl_public_decrypt($signature,$rawsig,$key);
255 $verify = (($rawsig && substr($rawsig,-32) === $hash) ? true : false);
259 logger('mod-diaspora: Message did not verify. Discarding.');
263 logger('mod-diaspora: Message verified.');
265 return $inner_decrypted;