<?php use Friendica\Network\Probe; require_once 'include/crypto.php'; function get_salmon_key($uri, $keyhash) { $ret = array(); logger('Fetching salmon key for '.$uri); $arr = Probe::lrdd($uri); 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) > 0) { 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); } } elseif (normalise_link($ret[$x]) == 'http://') { $ret[$x] = fetch_url($ret[$x]); } } } logger('Key located: ' . print_r($ret, true)); if (count($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['sprvkey']) { logger(sprintf("user '%s' (%d) does not have a salmon private key. Send failed.", $owner['username'], $owner['uid'])); return; } logger('slapper called for '.$url.'. Data: ' . $slap); // 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['spubkey'])), true); $precomputed = '.' . base64url_encode($data_type) . '.' . base64url_encode($encoding) . '.' . base64url_encode($algorithm); // GNU Social format $signature = base64url_encode(rsa_sign($data . $precomputed, $owner['sprvkey'])); // Compliant format $signature2 = base64url_encode(rsa_sign(str_replace('=', '', $data . $precomputed), $owner['sprvkey'])); // Old Status.net format $signature3 = base64url_encode(rsa_sign($data, $owner['sprvkey'])); // At first try the non compliant method that works for GNU Social $xmldata = array("me:env" => array("me:data" => $data, "@attributes" => array("type" => $data_type), "me:encoding" => $encoding, "me:alg" => $algorithm, "me:sig" => $signature, "@attributes2" => array("key_id" => $keyhash))); $namespaces = array("me" => "http://salmon-protocol.org/ns/magic-env"); $salmon = xml::from_array($xmldata, $xml, false, $namespaces); // slap them post_url($url, $salmon, array( 'Content-type: application/magic-envelope+xml', 'Content-length: ' . strlen($salmon) )); $a = get_app(); $return_code = $a->get_curl_code(); // check for success, e.g. 2xx if ($return_code > 299) { logger('GNU Social salmon failed. Falling back to compliant mode'); // Now try the compliant mode that normally isn't used for GNU Social $xmldata = array("me:env" => array("me:data" => $data, "@attributes" => array("type" => $data_type), "me:encoding" => $encoding, "me:alg" => $algorithm, "me:sig" => $signature2, "@attributes2" => array("key_id" => $keyhash))); $namespaces = array("me" => "http://salmon-protocol.org/ns/magic-env"); $salmon = xml::from_array($xmldata, $xml, false, $namespaces); // slap them post_url($url, $salmon, array( 'Content-type: application/magic-envelope+xml', 'Content-length: ' . strlen($salmon) )); $return_code = $a->get_curl_code(); } if ($return_code > 299) { logger('compliant salmon failed. Falling back to old status.net'); // Last try. This will most likely fail as well. $xmldata = array("me:env" => array("me:data" => $data, "@attributes" => array("type" => $data_type), "me:encoding" => $encoding, "me:alg" => $algorithm, "me:sig" => $signature3, "@attributes2" => array("key_id" => $keyhash))); $namespaces = array("me" => "http://salmon-protocol.org/ns/magic-env"); $salmon = xml::from_array($xmldata, $xml, false, $namespaces); // slap them post_url($url, $salmon, array( 'Content-type: application/magic-envelope+xml', 'Content-length: ' . strlen($salmon) )); $return_code = $a->get_curl_code(); } logger('slapper for '.$url.' returned ' . $return_code); if (! $return_code) { return -1; } if (($return_code == 503) && (stristr($a->get_curl_headers(), 'retry-after'))) { return -1; } return ((($return_code >= 200) && ($return_code < 300)) ? 0 : 1); }