diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/salmon.php | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/include/salmon.php b/include/salmon.php new file mode 100644 index 000000000..e1895ab75 --- /dev/null +++ b/include/salmon.php @@ -0,0 +1,201 @@ +<?php + +require_once('include/crypto.php'); + +function get_salmon_key($uri,$keyhash) { + $ret = array(); + + logger('Fetching salmon key for ' . $uri, LOGGER_DEBUG, LOG_INFO); + + $x = webfinger_rfc7033($uri,true); + + logger('webfinger returns: ' . print_r($x,true), LOGGER_DATA, LOG_DEBUG); + + if($x && array_key_exists('links',$x) && $x['links']) { + foreach($x['links'] as $link) { + if(array_key_exists('rel',$link) && $link['rel'] === 'magic-public-key') { + $ret[] = $link['href']; + } + } + } + + else { + $arr = old_webfinger($uri); + + logger('old webfinger returns: ' . print_r($arr,true), LOGGER_DATA, LOG_DEBUG); + + if(is_array($arr)) { + foreach($arr as $a) { + if($a['@attributes']['rel'] === 'magic-public-key') { + $ret[] = $a['@attributes']['href']; + } + } + } + else { + return ''; + } + } + + // We have found at least one key URL + // If it's inline, parse it - otherwise get the key + + if(count($ret)) { + for($x = 0; $x < count($ret); $x ++) { + if(substr($ret[$x],0,5) === 'data:') { + if(strstr($ret[$x],',')) + $ret[$x] = substr($ret[$x],strpos($ret[$x],',')+1); + else + $ret[$x] = substr($ret[$x],5); + } + else + $ret[$x] = fetch_url($ret[$x]); + } + } + + + logger('Key located: ' . print_r($ret,true), LOGGER_DEBUG, LOG_INFO); + + if(count($ret) == 1) { + + // We only found one one key so we don't care if the hash matches. + // If it's the wrong key we'll find out soon enough because + // message verification will fail. This also covers some older + // software which don't supply a keyhash. As long as they only + // have one key we'll be right. + + return $ret[0]; + } + else { + foreach($ret as $a) { + $hash = base64url_encode(hash('sha256',$a)); + if($hash == $keyhash) + return $a; + } + } + + return ''; +} + + + +function slapper($owner,$url,$slap) { + + // does contact have a salmon endpoint? + + if(! strlen($url)) + return; + + + if(! $owner['channel_prvkey']) { + logger(sprintf("channel '%s' (%d) does not have a salmon private key. Send failed.", + $owner['channel_address'],$owner['channel_id'])); + return; + } + + logger('slapper called for ' .$url . '. Data: ' . $slap, LOGGER_DATA, LOG_DEBUG); + + // create a magic envelope + + $data = base64url_encode($slap); + $data_type = 'application/atom+xml'; + $encoding = 'base64url'; + $algorithm = 'RSA-SHA256'; + $keyhash = base64url_encode(hash('sha256',salmon_key($owner['channel_pubkey'])),true); + + // precomputed base64url encoding of data_type, encoding, algorithm concatenated with periods + + $precomputed = '.YXBwbGljYXRpb24vYXRvbSt4bWw=.YmFzZTY0dXJs.UlNBLVNIQTI1Ng=='; + + $signature = base64url_encode(rsa_sign(str_replace('=','',$data . $precomputed),$owner['channel_prvkey'])); + + $signature2 = base64url_encode(rsa_sign($data . $precomputed,$owner['channel_prvkey'])); + + $signature3 = base64url_encode(rsa_sign($data,$owner['channel_prvkey'])); + + $salmon_tpl = get_markup_template('magicsig.tpl'); + + $salmon = replace_macros($salmon_tpl,array( + '$data' => $data, + '$encoding' => $encoding, + '$algorithm' => $algorithm, + '$keyhash' => $keyhash, + '$signature' => $signature + )); + + // slap them + + $redirects = 0; + + $ret = z_post_url($url,$salmon, $redirects, array('headers' => array( + 'Content-type: application/magic-envelope+xml', + 'Content-length: ' . strlen($salmon)) + )); + + + $return_code = $ret['return_code']; + + // check for success, e.g. 2xx + + if($return_code > 299) { + + logger('compliant salmon failed. Falling back to status.net hack2'); + + // Entirely likely that their salmon implementation is + // non-compliant. Let's try once more, this time only signing + // the data, without stripping '=' chars + + $salmon = replace_macros($salmon_tpl,array( + '$data' => $data, + '$encoding' => $encoding, + '$algorithm' => $algorithm, + '$keyhash' => $keyhash, + '$signature' => $signature2 + )); + + $redirects = 0; + + $ret = z_post_url($url,$salmon, $redirects, array('headers' => array( + 'Content-type: application/magic-envelope+xml', + 'Content-length: ' . strlen($salmon)) + )); + + + $return_code = $ret['return_code']; + + if($return_code > 299) { + + logger('compliant salmon failed. Falling back to status.net hack3'); + + // Entirely likely that their salmon implementation is + // non-compliant. Let's try once more, this time only signing + // the data, without the precomputed blob + + $salmon = replace_macros($salmon_tpl,array( + '$data' => $data, + '$encoding' => $encoding, + '$algorithm' => $algorithm, + '$keyhash' => $keyhash, + '$signature' => $signature3 + )); + + $redirects = 0; + + $ret = z_post_url($url,$salmon, $redirects, array('headers' => array( + 'Content-type: application/magic-envelope+xml', + 'Content-length: ' . strlen($salmon)) + )); + + + $return_code = $ret['return_code']; + } + } + logger('slapper for ' . $url . ' returned ' . $return_code); + + if(! $return_code) + return(-1); + if(($return_code == 503) && (stristr($ret['header'],'retry-after'))) + return(-1); + + return ((($return_code >= 200) && ($return_code < 300)) ? 0 : 1); +} + |