<?php // vim: foldmethod=marker /* Generic exception class */ class OAuthException extends Exception {/*{{{*/ // pass }/*}}}*/ class OAuthConsumer {/*{{{*/ public $key; public $secret; function __construct($key, $secret, $callback_url=NULL) {/*{{{*/ $this->key = $key; $this->secret = $secret; $this->callback_url = $callback_url; }/*}}}*/ function __toString() {/*{{{*/ return "OAuthConsumer[key=$this->key,secret=$this->secret]"; }/*}}}*/ }/*}}}*/ class OAuthToken {/*{{{*/ // access tokens and request tokens public $key; public $secret; /** * key = the token * secret = the token secret */ function __construct($key, $secret) {/*{{{*/ $this->key = $key; $this->secret = $secret; }/*}}}*/ /** * generates the basic string serialization of a token that a server * would respond to request_token and access_token calls with */ function to_string() {/*{{{*/ return "oauth_token=" . OAuthUtil::urlencode_rfc3986($this->key) . "&oauth_token_secret=" . OAuthUtil::urlencode_rfc3986($this->secret); }/*}}}*/ function __toString() {/*{{{*/ return $this->to_string(); }/*}}}*/ }/*}}}*/ class OAuthSignatureMethod {/*{{{*/ public function check_signature(&$request, $consumer, $token, $signature) { $built = $this->build_signature($request, $consumer, $token); return $built == $signature; } }/*}}}*/ class OAuthSignatureMethod_HMAC_SHA1 extends OAuthSignatureMethod {/*{{{*/ function get_name() {/*{{{*/ return "HMAC-SHA1"; }/*}}}*/ public function build_signature($request, $consumer, $token) {/*{{{*/ $base_string = $request->get_signature_base_string(); $request->base_string = $base_string; $key_parts = array( $consumer->secret, ($token) ? $token->secret : "" ); $key_parts = OAuthUtil::urlencode_rfc3986($key_parts); $key = implode('&', $key_parts); return base64_encode( hash_hmac('sha1', $base_string, $key, true)); }/*}}}*/ }/*}}}*/ class OAuthSignatureMethod_PLAINTEXT extends OAuthSignatureMethod {/*{{{*/ public function get_name() {/*{{{*/ return "PLAINTEXT"; }/*}}}*/ public function build_signature($request, $consumer, $token) {/*{{{*/ $sig = array( OAuthUtil::urlencode_rfc3986($consumer->secret) ); if ($token) { array_push($sig, OAuthUtil::urlencode_rfc3986($token->secret)); } else { array_push($sig, ''); } $raw = implode("&", $sig); // for debug purposes $request->base_string = $raw; return OAuthUtil::urlencode_rfc3986($raw); }/*}}}*/ }/*}}}*/ class OAuthSignatureMethod_RSA_SHA1 extends OAuthSignatureMethod {/*{{{*/ public function get_name() {/*{{{*/ return "RSA-SHA1"; }/*}}}*/ protected function fetch_public_cert(&$request) {/*{{{*/ // not implemented yet, ideas are: // (1) do a lookup in a table of trusted certs keyed off of consumer // (2) fetch via http using a url provided by the requester // (3) some sort of specific discovery code based on request // // either way should return a string representation of the certificate throw Exception("fetch_public_cert not implemented"); }/*}}}*/ protected function fetch_private_cert(&$request) {/*{{{*/ // not implemented yet, ideas are: // (1) do a lookup in a table of trusted certs keyed off of consumer // // either way should return a string representation of the certificate throw Exception("fetch_private_cert not implemented"); }/*}}}*/ public function build_signature(&$request, $consumer, $token) {/*{{{*/ $base_string = $request->get_signature_base_string(); $request->base_string = $base_string; // Fetch the private key cert based on the request $cert = $this->fetch_private_cert($request); // Pull the private key ID from the certificate $privatekeyid = openssl_get_privatekey($cert); // Sign using the key $ok = openssl_sign($base_string, $signature, $privatekeyid); // Release the key resource openssl_free_key($privatekeyid); return base64_encode($signature); } /*}}}*/ public function check_signature(&$request, $consumer, $token, $signature) {/*{{{*/ $decoded_sig = base64_decode($signature); $base_string = $request->get_signature_base_string(); // Fetch the public key cert based on the request $cert = $this->fetch_public_cert($request); // Pull the public key ID from the certificate $publickeyid = openssl_get_publickey($cert); // Check the computed signature against the one passed in the query $ok = openssl_verify($base_string, $decoded_sig, $publickeyid); // Release the key resource openssl_free_key($publickeyid); return $ok == 1; } /*}}}*/ }/*}}}*/ class OAuthRequest {/*{{{*/ private $parameters; private $http_method; private $http_url; // for debug purposes public $base_string; public static $version = '1.0'; function __construct($http_method, $http_url, $parameters=NULL) {/*{{{*/ @$parameters or $parameters = array(); $this->parameters = $parameters; $this->http_method = $http_method; $this->http_url = $http_url; }/*}}}*/ /** * attempt to build up a request from what was passed to the server */ public static function from_request($http_method=NULL, $http_url=NULL, $parameters=NULL) {/*{{{*/ $scheme = (!isset($_SERVER['HTTPS']) || $_SERVER['HTTPS'] != "on") ? 'http' : 'https'; @$http_url or $http_url = $scheme . '://' . $_SERVER['HTTP_HOST'] . ':' . $_SERVER['SERVER_PORT'] . $_SERVER['REQUEST_URI']; @$http_method or $http_method = $_SERVER['REQUEST_METHOD']; $request_headers = OAuthRequest::get_headers(); // let the library user override things however they'd like, if they know // which parameters to use then go for it, for example XMLRPC might want to // do this if ($parameters) { $req = new OAuthRequest($http_method, $http_url, $parameters); } else { // collect request parameters from query string (GET) and post-data (POST) if appropriate (note: POST vars have priority) $req_parameters = $_GET; if ($http_method == "POST" && ( @strstr($request_headers["Content-Type"], "application/x-www-form-urlencoded") || @strstr($_ENV["CONTENT_TYPE"], "application/x-www-form-urlencoded") )) { $req_parameters = array_merge($req_parameters, $_POST); } // next check for the auth header, we need to do some extra stuff // if that is the case, namely suck in the parameters from GET or POST // so that we can include them in the signature if (@substr($request_headers['Authorization'], 0, 6) == "OAuth ") { $header_parameters = OAuthRequest::split_header($request_headers['Authorization']); $parameters = array_merge($req_parameters, $header_parameters); $req = new OAuthRequest($http_method, $http_url, $parameters); } else $req = new OAuthRequest($http_method, $http_url, $req_parameters); } return $req; }/*}}}*/ /** * pretty much a helper function to set up the request */ public static function from_consumer_and_token($consumer, $token, $http_method, $http_url, $parameters=NULL) {/*{{{*/ @$parameters or $parameters = array(); $defaults = array("oauth_version" => OAuthRequest::$version, "oauth_nonce" => OAuthRequest::generate_nonce(), "oauth_timestamp" => OAuthRequest::generate_timestamp(), "oauth_consumer_key" => $consumer->key); $parameters = array_merge($defaults, $parameters); if ($token) { $parameters['oauth_token'] = $token->key; } return new OAuthRequest($http_method, $http_url, $parameters); }/*}}}*/ public function set_parameter($name, $value) {/*{{{*/ $this->parameters[$name] = $value; }/*}}}*/ public function get_parameter($name) {/*{{{*/ return isset($this->parameters[$name]) ? $this->parameters[$name] : null; }/*}}}*/ public function get_parameters() {/*{{{*/ return $this->parameters; }/*}}}*/ /** * Returns the normalized parameters of the request * * This will be all (except oauth_signature) parameters, * sorted first by key, and if duplicate keys, then by * value. * * The returned string will be all the key=value pairs * concated by &. * * @return string */ public function get_signable_parameters() {/*{{{*/ // Grab all parameters $params = $this->parameters; // Remove oauth_signature if present if (isset($params['oauth_signature'])) { unset($params['oauth_signature']); } // Urlencode both keys and values $keys = OAuthUtil::urlencode_rfc3986(array_keys($params)); $values = OAuthUtil::urlencode_rfc3986(array_values($params)); $params = array_combine($keys, $values); // Sort by keys (natsort) uksort($params, 'strcmp'); // Generate key=value pairs $pairs = array(); foreach ($params as $key=>$value ) { if (is_array($value)) { // If the value is an array, it's because there are multiple // with the same key, sort them, then add all the pairs natsort($value); foreach ($value as $v2) { $pairs[] = $key . '=' . $v2; } } else { $pairs[] = $key . '=' . $value; } } // Return the pairs, concated with & return implode('&', $pairs); }/*}}}*/ /** * Returns the base string of this request * * The base string defined as the method, the url * and the parameters (normalized), each urlencoded * and the concated with &. */ public function get_signature_base_string() {/*{{{*/ $parts = array( $this->get_normalized_http_method(), $this->get_normalized_http_url(), $this->get_signable_parameters() ); $parts = OAuthUtil::urlencode_rfc3986($parts); return implode('&', $parts); }/*}}}*/ /** * just uppercases the http method */ public function get_normalized_http_method() {/*{{{*/ return strtoupper($this->http_method); }/*}}}*/ /** * parses the url and rebuilds it to be * scheme://host/path */ public function get_normalized_http_url() {/*{{{*/ $parts = parse_url($this->http_url); $port = isset($parts['port']) ? $parts['port'] : null; $scheme = $parts['scheme']; $host = $parts['host']; $path = @$parts['path']; $port or $port = ($scheme == 'https') ? '443' : '80'; if (($scheme == 'https' && $port != '443') || ($scheme == 'http' && $port != '80')) { $host = "$host:$port"; } return "$scheme://$host$path"; }/*}}}*/ /** * builds a url usable for a GET request */ public function to_url() {/*{{{*/ $out = $this->get_normalized_http_url() . "?"; $out .= $this->to_postdata(); return $out; }/*}}}*/ /** * builds the data one would send in a POST request * * TODO(morten.fangel): * this function might be easily replaced with http_build_query() * and corrections for rfc3986 compatibility.. but not sure */ public function to_postdata() {/*{{{*/ $total = array(); foreach ($this->parameters as $k => $v) { if (is_array($v)) { foreach ($v as $va) { $total[] = OAuthUtil::urlencode_rfc3986($k) . "[]=" . OAuthUtil::urlencode_rfc3986($va); } } else { $total[] = OAuthUtil::urlencode_rfc3986($k) . "=" . OAuthUtil::urlencode_rfc3986($v); } } $out = implode("&", $total); return $out; }/*}}}*/ /** * builds the Authorization: header */ public function to_header() {/*{{{*/ $out ='Authorization: OAuth realm=""'; $total = array(); foreach ($this->parameters as $k => $v) { if (substr($k, 0, 5) != "oauth") continue; if (is_array($v)) throw new OAuthException('Arrays not supported in headers'); $out .= ',' . OAuthUtil::urlencode_rfc3986($k) . '="' . OAuthUtil::urlencode_rfc3986($v) . '"'; } return $out; }/*}}}*/ public function __toString() {/*{{{*/ return $this->to_url(); }/*}}}*/ public function sign_request($signature_method, $consumer, $token) {/*{{{*/ $this->set_parameter("oauth_signature_method", $signature_method->get_name()); $signature = $this->build_signature($signature_method, $consumer, $token); $this->set_parameter("oauth_signature", $signature); }/*}}}*/ public function build_signature($signature_method, $consumer, $token) {/*{{{*/ $signature = $signature_method->build_signature($this, $consumer, $token); return $signature; }/*}}}*/ /** * util function: current timestamp */ private static function generate_timestamp() {/*{{{*/ return time(); }/*}}}*/ /** * util function: current nonce */ private static function generate_nonce() {/*{{{*/ $mt = microtime(); $rand = mt_rand(); return md5($mt . $rand); // md5s look nicer than numbers }/*}}}*/ /** * util function for turning the Authorization: header into * parameters, has to do some unescaping */ private static function split_header($header) {/*{{{*/ $pattern = '/(([-_a-z]*)=("([^"]*)"|([^,]*)),?)/'; $offset = 0; $params = array(); while (preg_match($pattern, $header, $matches, PREG_OFFSET_CAPTURE, $offset) > 0) { $match = $matches[0]; $header_name = $matches[2][0]; $header_content = (isset($matches[5])) ? $matches[5][0] : $matches[4][0]; $params[$header_name] = OAuthUtil::urldecode_rfc3986( $header_content ); $offset = $match[1] + strlen($match[0]); } if (isset($params['realm'])) { unset($params['realm']); } return $params; }/*}}}*/ /** * helper to try to sort out headers for people who aren't running apache */ private static function get_headers() {/*{{{*/ if (function_exists('apache_request_headers')) { // we need this to get the actual Authorization: header // because apache tends to tell us it doesn't exist return apache_request_headers(); } // otherwise we don't have apache and are just going to have to hope // that $_SERVER actually contains what we need $out = array(); foreach ($_SERVER as $key => $value) { if (substr($key, 0, 5) == "HTTP_") { // this is chaos, basically it is just there to capitalize the first // letter of every word that is not an initial HTTP and strip HTTP // code from przemek $key = str_replace(" ", "-", ucwords(strtolower(str_replace("_", " ", substr($key, 5))))); $out[$key] = $value; } } return $out; }/*}}}*/ }/*}}}*/ class OAuthServer {/*{{{*/ protected $timestamp_threshold = 300; // in seconds, five minutes protected $version = 1.0; // hi blaine protected $signature_methods = array(); protected $data_store; function __construct($data_store) {/*{{{*/ $this->data_store = $data_store; }/*}}}*/ public function add_signature_method($signature_method) {/*{{{*/ $this->signature_methods[$signature_method->get_name()] = $signature_method; }/*}}}*/ // high level functions /** * process a request_token request * returns the request token on success */ public function fetch_request_token(&$request) {/*{{{*/ $this->get_version($request); $consumer = $this->get_consumer($request); // no token required for the initial token request $token = NULL; $this->check_signature($request, $consumer, $token); $new_token = $this->data_store->new_request_token($consumer); return $new_token; }/*}}}*/ /** * process an access_token request * returns the access token on success */ public function fetch_access_token(&$request) {/*{{{*/ $this->get_version($request); $consumer = $this->get_consumer($request); // requires authorized request token $token = $this->get_token($request, $consumer, "request"); $this->check_signature($request, $consumer, $token); $new_token = $this->data_store->new_access_token($token, $consumer); return $new_token; }/*}}}*/ /** * verify an api call, checks all the parameters */ public function verify_request(&$request) {/*{{{*/ $this->get_version($request); $consumer = $this->get_consumer($request); $token = $this->get_token($request, $consumer, "access"); $this->check_signature($request, $consumer, $token); return array($consumer, $token); }/*}}}*/ // Internals from here /** * version 1 */ private function get_version(&$request) {/*{{{*/ $version = $request->get_parameter("oauth_version"); if (!$version) { $version = 1.0; } if ($version && $version != $this->version) { throw new OAuthException("OAuth version '$version' not supported"); } return $version; }/*}}}*/ /** * figure out the signature with some defaults */ private function get_signature_method(&$request) {/*{{{*/ $signature_method = @$request->get_parameter("oauth_signature_method"); if (!$signature_method) { $signature_method = "PLAINTEXT"; } if (!in_array($signature_method, array_keys($this->signature_methods))) { throw new OAuthException( "Signature method '$signature_method' not supported try one of the following: " . implode(", ", array_keys($this->signature_methods)) ); } return $this->signature_methods[$signature_method]; }/*}}}*/ /** * try to find the consumer for the provided request's consumer key */ private function get_consumer(&$request) {/*{{{*/ $consumer_key = @$request->get_parameter("oauth_consumer_key"); if (!$consumer_key) { throw new OAuthException("Invalid consumer key"); } $consumer = $this->data_store->lookup_consumer($consumer_key); if (!$consumer) { throw new OAuthException("Invalid consumer"); } return $consumer; }/*}}}*/ /** * try to find the token for the provided request's token key */ private function get_token(&$request, $consumer, $token_type="access") {/*{{{*/ $token_field = @$request->get_parameter('oauth_token'); $token = $this->data_store->lookup_token( $consumer, $token_type, $token_field ); if (!$token) { throw new OAuthException("Invalid $token_type token: $token_field"); } return $token; }/*}}}*/ /** * all-in-one function to check the signature on a request * should guess the signature method appropriately */ private function check_signature(&$request, $consumer, $token) {/*{{{*/ // this should probably be in a different method $timestamp = @$request->get_parameter('oauth_timestamp'); $nonce = @$request->get_parameter('oauth_nonce'); $this->check_timestamp($timestamp); $this->check_nonce($consumer, $token, $nonce, $timestamp); $signature_method = $this->get_signature_method($request); $signature = $request->get_parameter('oauth_signature'); $valid_sig = $signature_method->check_signature( $request, $consumer, $token, $signature ); if (!$valid_sig) { throw new OAuthException("Invalid signature"); } }/*}}}*/ /** * check that the timestamp is new enough */ private function check_timestamp($timestamp) {/*{{{*/ // verify that timestamp is recentish $now = time(); if ($now - $timestamp > $this->timestamp_threshold) { throw new OAuthException("Expired timestamp, yours $timestamp, ours $now"); } }/*}}}*/ /** * check that the nonce is not repeated */ private function check_nonce($consumer, $token, $nonce, $timestamp) {/*{{{*/ // verify that the nonce is uniqueish $found = $this->data_store->lookup_nonce($consumer, $token, $nonce, $timestamp); if ($found) { throw new OAuthException("Nonce already used: $nonce"); } }/*}}}*/ }/*}}}*/ class OAuthDataStore {/*{{{*/ function lookup_consumer($consumer_key) {/*{{{*/ // implement me }/*}}}*/ function lookup_token($consumer, $token_type, $token) {/*{{{*/ // implement me }/*}}}*/ function lookup_nonce($consumer, $token, $nonce, $timestamp) {/*{{{*/ // implement me }/*}}}*/ function new_request_token($consumer) {/*{{{*/ // return a new token attached to this consumer }/*}}}*/ function new_access_token($token, $consumer) {/*{{{*/ // return a new access token attached to this consumer // for the user associated with this token if the request token // is authorized // should also invalidate the request token }/*}}}*/ }/*}}}*/ /* A very naive dbm-based oauth storage */ class SimpleOAuthDataStore extends OAuthDataStore {/*{{{*/ private $dbh; function __construct($path = "oauth.gdbm") {/*{{{*/ $this->dbh = dba_popen($path, 'c', 'gdbm'); }/*}}}*/ function __destruct() {/*{{{*/ dba_close($this->dbh); }/*}}}*/ function lookup_consumer($consumer_key) {/*{{{*/ $rv = dba_fetch("consumer_$consumer_key", $this->dbh); if ($rv === FALSE) { return NULL; } $obj = unserialize($rv); if (!($obj instanceof OAuthConsumer)) { return NULL; } return $obj; }/*}}}*/ function lookup_token($consumer, $token_type, $token) {/*{{{*/ $rv = dba_fetch("${token_type}_${token}", $this->dbh); if ($rv === FALSE) { return NULL; } $obj = unserialize($rv); if (!($obj instanceof OAuthToken)) { return NULL; } return $obj; }/*}}}*/ function lookup_nonce($consumer, $token, $nonce, $timestamp) {/*{{{*/ if (dba_exists("nonce_$nonce", $this->dbh)) { return TRUE; } else { dba_insert("nonce_$nonce", "1", $this->dbh); return FALSE; } }/*}}}*/ function new_token($consumer, $type="request") {/*{{{*/ $key = md5(time()); $secret = time() + time(); $token = new OAuthToken($key, md5(md5($secret))); if (!dba_insert("${type}_$key", serialize($token), $this->dbh)) { throw new OAuthException("doooom!"); } return $token; }/*}}}*/ function new_request_token($consumer) {/*{{{*/ return $this->new_token($consumer, "request"); }/*}}}*/ function new_access_token($token, $consumer) {/*{{{*/ $token = $this->new_token($consumer, 'access'); dba_delete("request_" . $token->key, $this->dbh); return $token; }/*}}}*/ }/*}}}*/ class OAuthUtil {/*{{{*/ public static function urlencode_rfc3986($input) {/*{{{*/ if (is_array($input)) { return array_map(array('OAuthUtil','urlencode_rfc3986'), $input); } else if (is_scalar($input)) { return str_replace('+', ' ', str_replace('%7E', '~', rawurlencode($input))); } else { return ''; } }/*}}}*/ // This decode function isn't taking into consideration the above // modifications to the encoding process. However, this method doesn't // seem to be used anywhere so leaving it as is. public static function urldecode_rfc3986($string) {/*{{{*/ return rawurldecode($string); }/*}}}*/ }/*}}}*/ ?>