is_request_to_rest_api() ) { return $user_id; } if ( is_ssl() ) { return $this->perform_basic_authentication(); } else { return $this->perform_oauth_authentication(); } } /** * Check for authentication error. * * @param WP_Error|null|bool $error * @return WP_Error|null|bool */ public function check_authentication_error( $error ) { // Passthrough other errors. if ( ! empty( $error ) ) { return $error; } return $this->get_error(); } /** * Set authentication error. * * @param WP_Error $error Authication error data. */ protected function set_error( $error ) { // Reset user. $this->user = null; $this->error = $error; } /** * Get authentication error. * * @return WP_Error|null. */ protected function get_error() { return $this->error; } /** * Basic Authentication. * * SSL-encrypted requests are not subject to sniffing or man-in-the-middle * attacks, so the request can be authenticated by simply looking up the user * associated with the given consumer key and confirming the consumer secret * provided is valid. * * @return int|bool */ private function perform_basic_authentication() { $this->auth_method = 'basic_auth'; $consumer_key = ''; $consumer_secret = ''; // If the $_GET parameters are present, use those first. if ( ! empty( $_GET['consumer_key'] ) && ! empty( $_GET['consumer_secret'] ) ) { $consumer_key = $_GET['consumer_key']; $consumer_secret = $_GET['consumer_secret']; } // If the above is not present, we will do full basic auth. if ( ! $consumer_key && ! empty( $_SERVER['PHP_AUTH_USER'] ) && ! empty( $_SERVER['PHP_AUTH_PW'] ) ) { $consumer_key = $_SERVER['PHP_AUTH_USER']; $consumer_secret = $_SERVER['PHP_AUTH_PW']; } // Stop if don't have any key. if ( ! $consumer_key || ! $consumer_secret ) { return false; } // Get user data. $this->user = $this->get_user_data_by_consumer_key( $consumer_key ); if ( empty( $this->user ) ) { return false; } // Validate user secret. if ( ! hash_equals( $this->user->consumer_secret, $consumer_secret ) ) { $this->set_error( new WP_Error( 'woocommerce_rest_authentication_error', __( 'Consumer secret is invalid.', 'woocommerce' ), array( 'status' => 401 ) ) ); return false; } return $this->user->user_id; } /** * Parse the Authorization header into parameters. * * @since 3.0.0 * * @param string $header Authorization header value (not including "Authorization: " prefix). * * @return array Map of parameter values. */ public function parse_header( $header ) { if ( 'OAuth ' !== substr( $header, 0, 6 ) ) { return array(); } // From OAuth PHP library, used under MIT license. $params = array(); if ( preg_match_all( '/(oauth_[a-z_-]*)=(:?"([^"]*)"|([^,]*))/', $header, $matches ) ) { foreach ( $matches[1] as $i => $h ) { $params[ $h ] = urldecode( empty( $matches[3][ $i ] ) ? $matches[4][ $i ] : $matches[3][ $i ] ); } if ( isset( $params['realm'] ) ) { unset( $params['realm'] ); } } return $params; } /** * Get the authorization header. * * On certain systems and configurations, the Authorization header will be * stripped out by the server or PHP. Typically this is then used to * generate `PHP_AUTH_USER`/`PHP_AUTH_PASS` but not passed on. We use * `getallheaders` here to try and grab it out instead. * * @since 3.0.0 * * @return string Authorization header if set. */ public function get_authorization_header() { if ( ! empty( $_SERVER['HTTP_AUTHORIZATION'] ) ) { return wp_unslash( $_SERVER['HTTP_AUTHORIZATION'] ); } if ( function_exists( 'getallheaders' ) ) { $headers = getallheaders(); // Check for the authoization header case-insensitively. foreach ( $headers as $key => $value ) { if ( 'authorization' === strtolower( $key ) ) { return $value; } } } return ''; } /** * Get oAuth parameters from $_GET, $_POST or request header. * * @since 3.0.0 * * @return array|WP_Error */ public function get_oauth_parameters() { $params = array_merge( $_GET, $_POST ); $params = wp_unslash( $params ); $header = $this->get_authorization_header(); if ( ! empty( $header ) ) { // Trim leading spaces. $header = trim( $header ); $header_params = $this->parse_header( $header ); if ( ! empty( $header_params ) ) { $params = array_merge( $params, $header_params ); } } $param_names = array( 'oauth_consumer_key', 'oauth_timestamp', 'oauth_nonce', 'oauth_signature', 'oauth_signature_method', ); $errors = array(); $have_one = false; // Check for required OAuth parameters. foreach ( $param_names as $param_name ) { if ( empty( $params[ $param_name ] ) ) { $errors[] = $param_name; } else { $have_one = true; } } // All keys are missing, so we're probably not even trying to use OAuth. if ( ! $have_one ) { return array(); } // If we have at least one supplied piece of data, and we have an error, // then it's a failed authentication. if ( ! empty( $errors ) ) { $message = sprintf( _n( 'Missing OAuth parameter %s', 'Missing OAuth parameters %s', count( $errors ), 'woocommerce' ), implode( ', ', $errors ) ); $this->set_error( new WP_Error( 'woocommerce_rest_authentication_missing_parameter', $message, array( 'status' => 401 ) ) ); return array(); } return $params; } /** * Perform OAuth 1.0a "one-legged" (http://oauthbible.com/#oauth-10a-one-legged) authentication for non-SSL requests. * * This is required so API credentials cannot be sniffed or intercepted when making API requests over plain HTTP. * * This follows the spec for simple OAuth 1.0a authentication (RFC 5849) as closely as possible, with two exceptions: * * 1) There is no token associated with request/responses, only consumer keys/secrets are used. * * 2) The OAuth parameters are included as part of the request query string instead of part of the Authorization header, * This is because there is no cross-OS function within PHP to get the raw Authorization header. * * @link http://tools.ietf.org/html/rfc5849 for the full spec. * * @return int|bool */ private function perform_oauth_authentication() { $this->auth_method = 'oauth1'; $params = $this->get_oauth_parameters(); if ( empty( $params ) ) { return false; } // Fetch WP user by consumer key. $this->user = $this->get_user_data_by_consumer_key( $params['oauth_consumer_key'] ); if ( empty( $this->user ) ) { $this->set_error( new WP_Error( 'woocommerce_rest_authentication_error', __( 'Consumer key is invalid.', 'woocommerce' ), array( 'status' => 401 ) ) ); return false; } // Perform OAuth validation. $signature = $this->check_oauth_signature( $this->user, $params ); if ( is_wp_error( $signature ) ) { $this->set_error( $signature ); return false; } $timestamp_and_nonce = $this->check_oauth_timestamp_and_nonce( $this->user, $params['oauth_timestamp'], $params['oauth_nonce'] ); if ( is_wp_error( $timestamp_and_nonce ) ) { $this->set_error( $timestamp_and_nonce ); return false; } return $this->user->user_id; } /** * Verify that the consumer-provided request signature matches our generated signature, * this ensures the consumer has a valid key/secret. * * @param stdClass $user * @param array $params The request parameters. * @return true|WP_Error */ private function check_oauth_signature( $user, $params ) { $http_method = strtoupper( $_SERVER['REQUEST_METHOD'] ); $request_path = parse_url( $_SERVER['REQUEST_URI'], PHP_URL_PATH ); $wp_base = get_home_url( null, '/', 'relative' ); if ( substr( $request_path, 0, strlen( $wp_base ) ) === $wp_base ) { $request_path = substr( $request_path, strlen( $wp_base ) ); } $base_request_uri = rawurlencode( get_home_url( null, $request_path ) ); // Get the signature provided by the consumer and remove it from the parameters prior to checking the signature. $consumer_signature = rawurldecode( str_replace( ' ', '+', $params['oauth_signature'] ) ); unset( $params['oauth_signature'] ); // Sort parameters. if ( ! uksort( $params, 'strcmp' ) ) { return new WP_Error( 'woocommerce_rest_authentication_error', __( 'Invalid signature - failed to sort parameters.', 'woocommerce' ), array( 'status' => 401 ) ); } // Normalize parameter key/values. $params = $this->normalize_parameters( $params ); $query_string = implode( '%26', $this->join_with_equals_sign( $params ) ); // Join with ampersand. $string_to_sign = $http_method . '&' . $base_request_uri . '&' . $query_string; if ( 'HMAC-SHA1' !== $params['oauth_signature_method'] && 'HMAC-SHA256' !== $params['oauth_signature_method'] ) { return new WP_Error( 'woocommerce_rest_authentication_error', __( 'Invalid signature - signature method is invalid.', 'woocommerce' ), array( 'status' => 401 ) ); } $hash_algorithm = strtolower( str_replace( 'HMAC-', '', $params['oauth_signature_method'] ) ); $secret = $user->consumer_secret . '&'; $signature = base64_encode( hash_hmac( $hash_algorithm, $string_to_sign, $secret, true ) ); if ( ! hash_equals( $signature, $consumer_signature ) ) { return new WP_Error( 'woocommerce_rest_authentication_error', __( 'Invalid signature - provided signature does not match.', 'woocommerce' ), array( 'status' => 401 ) ); } return true; } /** * Creates an array of urlencoded strings out of each array key/value pairs. * * @param array $params Array of parameters to convert. * @param array $query_params Array to extend. * @param string $key Optional Array key to append * @return string Array of urlencoded strings */ private function join_with_equals_sign( $params, $query_params = array(), $key = '' ) { foreach ( $params as $param_key => $param_value ) { if ( $key ) { $param_key = $key . '%5B' . $param_key . '%5D'; // Handle multi-dimensional array. } if ( is_array( $param_value ) ) { $query_params = $this->join_with_equals_sign( $param_value, $query_params, $param_key ); } else { $string = $param_key . '=' . $param_value; // Join with equals sign. $query_params[] = wc_rest_urlencode_rfc3986( $string ); } } return $query_params; } /** * Normalize each parameter by assuming each parameter may have already been * encoded, so attempt to decode, and then re-encode according to RFC 3986. * * Note both the key and value is normalized so a filter param like: * * 'filter[period]' => 'week' * * is encoded to: * * 'filter%255Bperiod%255D' => 'week' * * This conforms to the OAuth 1.0a spec which indicates the entire query string * should be URL encoded. * * @see rawurlencode() * @param array $parameters Un-normalized parameters. * @return array Normalized parameters. */ private function normalize_parameters( $parameters ) { $keys = wc_rest_urlencode_rfc3986( array_keys( $parameters ) ); $values = wc_rest_urlencode_rfc3986( array_values( $parameters ) ); $parameters = array_combine( $keys, $values ); return $parameters; } /** * Verify that the timestamp and nonce provided with the request are valid. This prevents replay attacks where * an attacker could attempt to re-send an intercepted request at a later time. * * - A timestamp is valid if it is within 15 minutes of now. * - A nonce is valid if it has not been used within the last 15 minutes. * * @param stdClass $user * @param int $timestamp the unix timestamp for when the request was made * @param string $nonce a unique (for the given user) 32 alphanumeric string, consumer-generated * @return bool|WP_Error */ private function check_oauth_timestamp_and_nonce( $user, $timestamp, $nonce ) { global $wpdb; $valid_window = 15 * 60; // 15 minute window. if ( ( $timestamp < time() - $valid_window ) || ( $timestamp > time() + $valid_window ) ) { return new WP_Error( 'woocommerce_rest_authentication_error', __( 'Invalid timestamp.', 'woocommerce' ), array( 'status' => 401 ) ); } $used_nonces = maybe_unserialize( $user->nonces ); if ( empty( $used_nonces ) ) { $used_nonces = array(); } if ( in_array( $nonce, $used_nonces ) ) { return new WP_Error( 'woocommerce_rest_authentication_error', __( 'Invalid nonce - nonce has already been used.', 'woocommerce' ), array( 'status' => 401 ) ); } $used_nonces[ $timestamp ] = $nonce; // Remove expired nonces. foreach ( $used_nonces as $nonce_timestamp => $nonce ) { if ( $nonce_timestamp < ( time() - $valid_window ) ) { unset( $used_nonces[ $nonce_timestamp ] ); } } $used_nonces = maybe_serialize( $used_nonces ); $wpdb->update( $wpdb->prefix . 'woocommerce_api_keys', array( 'nonces' => $used_nonces ), array( 'key_id' => $user->key_id ), array( '%s' ), array( '%d' ) ); return true; } /** * Return the user data for the given consumer_key. * * @param string $consumer_key * @return array */ private function get_user_data_by_consumer_key( $consumer_key ) { global $wpdb; $consumer_key = wc_api_hash( sanitize_text_field( $consumer_key ) ); $user = $wpdb->get_row( $wpdb->prepare( " SELECT key_id, user_id, permissions, consumer_key, consumer_secret, nonces FROM {$wpdb->prefix}woocommerce_api_keys WHERE consumer_key = %s ", $consumer_key ) ); return $user; } /** * Check that the API keys provided have the proper key-specific permissions to either read or write API resources. * * @param string $method Request method. * @return bool|WP_Error */ private function check_permissions( $method ) { $permissions = $this->user->permissions; switch ( $method ) { case 'HEAD' : case 'GET' : if ( 'read' !== $permissions && 'read_write' !== $permissions ) { return new WP_Error( 'woocommerce_rest_authentication_error', __( 'The API key provided does not have read permissions.', 'woocommerce' ), array( 'status' => 401 ) ); } break; case 'POST' : case 'PUT' : case 'PATCH' : case 'DELETE' : if ( 'write' !== $permissions && 'read_write' !== $permissions ) { return new WP_Error( 'woocommerce_rest_authentication_error', __( 'The API key provided does not have write permissions.', 'woocommerce' ), array( 'status' => 401 ) ); } break; default : return new WP_Error( 'woocommerce_rest_authentication_error', __( 'Unknown request method.', 'woocommerce' ), array( 'status' => 401 ) ); } return true; } /** * Updated API Key last access datetime. */ private function update_last_access() { global $wpdb; $wpdb->update( $wpdb->prefix . 'woocommerce_api_keys', array( 'last_access' => current_time( 'mysql' ) ), array( 'key_id' => $this->user->key_id ), array( '%s' ), array( '%d' ) ); } /** * If the consumer_key and consumer_secret $_GET parameters are NOT provided * and the Basic auth headers are either not present or the consumer secret does not match the consumer * key provided, then return the correct Basic headers and an error message. * * @param WP_REST_Response $response Current response being served. * @return WP_REST_Response */ public function send_unauthorized_headers( $response ) { if ( is_wp_error( $this->get_error() ) && 'basic_auth' === $this->auth_method ) { $auth_message = __( 'WooCommerce API. Use a consumer key in the username field and a consumer secret in the password field.', 'woocommerce' ); $response->header( 'WWW-Authenticate', 'Basic realm="' . $auth_message . '"', true ); } return $response; } /** * Check for user permissions and register last access. * * @param mixed $result Response to replace the requested version with. * @param WP_REST_Server $server Server instance. * @param WP_REST_Request $request Request used to generate the response. * @return mixed */ public function check_user_permissions( $result, $server, $request ) { if ( $this->user ) { // Check API Key permissions. $allowed = $this->check_permissions( $request->get_method() ); if ( is_wp_error( $allowed ) ) { return $allowed; } // Register last access. $this->update_last_access(); } return $result; } } new WC_REST_Authentication();