| @@ -1,20 +1,14 @@ | ||
| 1 | 1 | <?php |
| 2 | -/** | |
| 3 | - * Signature class file. | |
| 4 | - * | |
| 5 | - * @package Activitypub | |
| 6 | - */ | |
| 7 | - | |
| 8 | 2 | namespace Activitypub; |
| 9 | 3 | |
| 10 | -use Activitypub\Collection\Actors; | |
| 11 | -use Activitypub\Collection\Remote_Actors; | |
| 12 | -use Activitypub\Signature\Http_Message_Signature; | |
| 13 | -use Activitypub\Signature\Http_Signature_Draft; | |
| 4 | +use WP_Error; | |
| 5 | +use DateTime; | |
| 6 | +use DateTimeZone; | |
| 7 | +use Activitypub\Collection\Users; | |
| 14 | 8 | |
| 15 | 9 | /** |
| 16 | - * ActivityPub Signature Class. | |
| 10 | + * ActivityPub Signature Class | |
| 17 | 11 | * |
| 18 | 12 | * @author Matthias Pfefferle |
| 19 | 13 | * @author Django Doucet |
| 20 | 14 | */ |
| @@ -20,266 +14,191 @@ | ||
| 20 | 14 | */ |
| 21 | 15 | class Signature { |
| 22 | 16 | |
| 23 | 17 | /** |
| 24 | - * Initialize the class. | |
| 25 | - */ | |
| 26 | - public static function init() { | |
| 27 | - \add_filter( 'http_request_args', array( self::class, 'sign_request' ), 0, 2 ); // Ahead of all other filters, so signature is set. | |
| 28 | - \add_filter( 'http_response', array( self::class, 'maybe_double_knock' ), 10, 3 ); | |
| 29 | - } | |
| 30 | - | |
| 31 | - /** | |
| 32 | - * Sign an HTTP Request. | |
| 18 | + * Return the public key for a given user. | |
| 33 | 19 | * |
| 34 | - * @param array $args An array of HTTP request arguments. | |
| 35 | - * @param string $url The request URL. | |
| 20 | + * @param int $user_id The WordPress User ID. | |
| 21 | + * @param bool $force Force the generation of a new key pair. | |
| 36 | 22 | * |
| 37 | - * @return array Request arguments with signature headers. | |
| 23 | + * @return mixed The public key. | |
| 38 | 24 | */ |
| 39 | - public static function sign_request( $args, $url ) { | |
| 40 | - // Bail if there's nothing to sign with. | |
| 41 | - if ( ! isset( $args['key_id'], $args['private_key'] ) ) { | |
| 42 | - return $args; | |
| 25 | + public static function get_public_key_for( $user_id, $force = false ) { | |
| 26 | + if ( $force ) { | |
| 27 | + self::generate_key_pair_for( $user_id ); | |
| 43 | 28 | } |
| 44 | 29 | |
| 45 | - if ( '1' === \get_option( 'activitypub_rfc9421_signature' ) && self::could_support_rfc9421( $url ) ) { | |
| 46 | - $signature = new Http_Message_Signature(); | |
| 47 | - } else { | |
| 48 | - $signature = new Http_Signature_Draft(); | |
| 49 | - } | |
| 30 | + $key_pair = self::get_keypair_for( $user_id ); | |
| 50 | 31 | |
| 51 | - return $signature->sign( $args, $url ); | |
| 32 | + return $key_pair['public_key']; | |
| 52 | 33 | } |
| 53 | 34 | |
| 54 | 35 | /** |
| 55 | - * Verifies the http signatures | |
| 36 | + * Return the private key for a given user. | |
| 56 | 37 | * |
| 57 | - * @param \WP_REST_Request|array $request The request object or $_SERVER array. | |
| 38 | + * @param int $user_id The WordPress User ID. | |
| 39 | + * @param bool $force Force the generation of a new key pair. | |
| 58 | 40 | * |
| 59 | - * @return bool|\WP_Error A boolean or WP_Error. | |
| 41 | + * @return mixed The private key. | |
| 60 | 42 | */ |
| 61 | - public static function verify_http_signature( $request ) { | |
| 62 | - if ( is_object( $request ) ) { // REST Request object. | |
| 63 | - $body = $request->get_body(); | |
| 64 | - $headers = $request->get_headers(); | |
| 65 | - $headers['(request-target)'][0] = strtolower( $request->get_method() ) . ' ' . self::get_route( $request ); | |
| 66 | - } else { | |
| 67 | - $headers = self::format_server_request( $request ); | |
| 68 | - $headers['(request-target)'][0] = strtolower( $headers['request_method'][0] ) . ' ' . $headers['request_uri'][0]; | |
| 43 | + public static function get_private_key_for( $user_id, $force = false ) { | |
| 44 | + if ( $force ) { | |
| 45 | + self::generate_key_pair_for( $user_id ); | |
| 69 | 46 | } |
| 70 | 47 | |
| 71 | - $signature = isset( $headers['signature_input'] ) ? new Http_Message_Signature() : new Http_Signature_Draft(); | |
| 48 | + $key_pair = self::get_keypair_for( $user_id ); | |
| 72 | 49 | |
| 73 | - return $signature->verify( $headers, $body ?? null ); | |
| 50 | + return $key_pair['private_key']; | |
| 74 | 51 | } |
| 75 | 52 | |
| 76 | 53 | /** |
| 77 | - * If a request with RFC-9421 signature fails, we try again with the Draft Cavage signature. | |
| 54 | + * Return the key pair for a given user. | |
| 78 | 55 | * |
| 79 | - * @param array $response HTTP response. | |
| 80 | - * @param array $args HTTP request arguments. | |
| 81 | - * @param string $url The request URL. | |
| 56 | + * @param int $user_id The WordPress User ID. | |
| 82 | 57 | * |
| 83 | - * @return array The HTTP response. | |
| 58 | + * @return array The key pair. | |
| 84 | 59 | */ |
| 85 | - public static function maybe_double_knock( $response, $args, $url ) { | |
| 86 | - // Bail if it didn't use an RFC-9421 signature or there's nothing to sign with. | |
| 87 | - if ( ! isset( $args['key_id'], $args['private_key'], $args['headers']['Signature-Input'] ) ) { | |
| 88 | - return $response; | |
| 89 | - } | |
| 60 | + public static function get_keypair_for( $user_id ) { | |
| 61 | + $option_key = self::get_signature_options_key_for( $user_id ); | |
| 62 | + $key_pair = \get_option( $option_key ); | |
| 90 | 63 | |
| 91 | - $response_code = \wp_remote_retrieve_response_code( $response ); | |
| 92 | - | |
| 93 | - // Fall back to Draft Cavage signature for any 4xx responses. | |
| 94 | - if ( $response_code >= 400 && $response_code < 500 ) { | |
| 95 | - unset( $args['headers']['Signature'], $args['headers']['Signature-Input'], $args['headers']['Content-Digest'] ); | |
| 96 | - self::rfc9421_add_unsupported_host( $url ); | |
| 97 | - | |
| 98 | - $args = ( new Http_Signature_Draft() )->sign( $args, $url ); | |
| 99 | - $response = \wp_safe_remote_request( $url, $args ); | |
| 64 | + if ( ! $key_pair ) { | |
| 65 | + $key_pair = self::generate_key_pair_for( $user_id ); | |
| 100 | 66 | } |
| 101 | 67 | |
| 102 | - return $response; | |
| 68 | + return $key_pair; | |
| 103 | 69 | } |
| 104 | 70 | |
| 105 | 71 | /** |
| 106 | - * Formats the $_SERVER to resemble the WP_REST_REQUEST array, | |
| 107 | - * for use with verify_http_signature(). | |
| 72 | + * Generates the pair keys | |
| 108 | 73 | * |
| 109 | - * @param array $server The $_SERVER array. | |
| 74 | + * @param int $user_id The WordPress User ID. | |
| 110 | 75 | * |
| 111 | - * @return array $request The formatted request array. | |
| 76 | + * @return array The key pair. | |
| 112 | 77 | */ |
| 113 | - public static function format_server_request( $server ) { | |
| 114 | - $headers = array(); | |
| 78 | + protected static function generate_key_pair_for( $user_id ) { | |
| 79 | + $option_key = self::get_signature_options_key_for( $user_id ); | |
| 80 | + $key_pair = self::check_legacy_key_pair_for( $user_id ); | |
| 115 | 81 | |
| 116 | - foreach ( $server as $key => $value ) { | |
| 117 | - $key = \str_replace( 'http_', '', \strtolower( $key ) ); | |
| 118 | - $headers[ $key ][] = \wp_unslash( $value ); | |
| 82 | + if ( $key_pair ) { | |
| 83 | + \add_option( $option_key, $key_pair ); | |
| 119 | 84 | |
| 85 | + return $key_pair; | |
| 120 | 86 | } |
| 121 | 87 | |
| 122 | - return $headers; | |
| 123 | - } | |
| 88 | + $config = array( | |
| 89 | + 'digest_alg' => 'sha512', | |
| 90 | + 'private_key_bits' => 2048, | |
| 91 | + 'private_key_type' => \OPENSSL_KEYTYPE_RSA, | |
| 92 | + ); | |
| 124 | 93 | |
| 125 | - /** | |
| 126 | - * Returns route. | |
| 127 | - * | |
| 128 | - * @param \WP_REST_Request $request The request object. | |
| 129 | - * | |
| 130 | - * @return string | |
| 131 | - */ | |
| 132 | - private static function get_route( $request ) { | |
| 133 | - // Check if the route starts with "index.php". | |
| 134 | - if ( str_starts_with( $request->get_route(), '/index.php' ) || ! rest_get_url_prefix() ) { | |
| 135 | - $route = $request->get_route(); | |
| 136 | - } else { | |
| 137 | - $route = '/' . rest_get_url_prefix() . '/' . ltrim( $request->get_route(), '/' ); | |
| 138 | - } | |
| 94 | + $key = \openssl_pkey_new( $config ); | |
| 95 | + $priv_key = null; | |
| 139 | 96 | |
| 140 | - // Fix route for subdirectory installations. | |
| 141 | - $path = \wp_parse_url( \get_home_url(), PHP_URL_PATH ); | |
| 97 | + \openssl_pkey_export( $key, $priv_key ); | |
| 142 | 98 | |
| 143 | - if ( \is_string( $path ) ) { | |
| 144 | - $path = trim( $path, '/' ); | |
| 145 | - } | |
| 99 | + $detail = \openssl_pkey_get_details( $key ); | |
| 146 | 100 | |
| 147 | - if ( $path ) { | |
| 148 | - $route = '/' . $path . $route; | |
| 101 | + // check if keys are valid | |
| 102 | + if ( | |
| 103 | + empty( $priv_key ) || ! is_string( $priv_key ) || | |
| 104 | + ! isset( $detail['key'] ) || ! is_string( $detail['key'] ) | |
| 105 | + ) { | |
| 106 | + return array( | |
| 107 | + 'private_key' => null, | |
| 108 | + 'public_key' => null, | |
| 109 | + ); | |
| 149 | 110 | } |
| 150 | 111 | |
| 151 | - return $route; | |
| 152 | - } | |
| 112 | + $key_pair = array( | |
| 113 | + 'private_key' => $priv_key, | |
| 114 | + 'public_key' => $detail['key'], | |
| 115 | + ); | |
| 153 | 116 | |
| 154 | - /** | |
| 155 | - * Check if RFC-9421 signature could be supported. | |
| 156 | - * | |
| 157 | - * @param string $url The URL to check. | |
| 158 | - * | |
| 159 | - * @return bool True, if RFC-9421 signature could be supported, false otherwise. | |
| 160 | - */ | |
| 161 | - private static function could_support_rfc9421( $url ) { | |
| 162 | - $host = \wp_parse_url( $url, \PHP_URL_HOST ); | |
| 163 | - $list = \get_option( 'activitypub_rfc9421_unsupported', array() ); | |
| 117 | + // persist keys | |
| 118 | + \add_option( $option_key, $key_pair ); | |
| 164 | 119 | |
| 165 | - if ( isset( $list[ $host ] ) ) { | |
| 166 | - if ( $list[ $host ] > \time() ) { | |
| 167 | - return false; | |
| 168 | - } | |
| 169 | - | |
| 170 | - unset( $list[ $host ] ); | |
| 171 | - \update_option( 'activitypub_rfc9421_unsupported', $list ); | |
| 172 | - } | |
| 173 | - | |
| 174 | - return true; | |
| 120 | + return $key_pair; | |
| 175 | 121 | } |
| 176 | 122 | |
| 177 | 123 | /** |
| 178 | - * Set RFC-9421 signature unsupported for a given host. | |
| 124 | + * Return the option key for a given user. | |
| 179 | 125 | * |
| 180 | - * @param string $url The URL to set. | |
| 181 | - */ | |
| 182 | - private static function rfc9421_add_unsupported_host( $url ) { | |
| 183 | - $list = \get_option( 'activitypub_rfc9421_unsupported', array() ); | |
| 184 | - $host = \wp_parse_url( $url, \PHP_URL_HOST ); | |
| 185 | - | |
| 186 | - $list[ $host ] = \time() + MONTH_IN_SECONDS; | |
| 187 | - \update_option( 'activitypub_rfc9421_unsupported', $list, false ); | |
| 188 | - } | |
| 189 | - | |
| 190 | - /** | |
| 191 | - * Return the public key for a given user. | |
| 126 | + * @param int $user_id The WordPress User ID. | |
| 192 | 127 | * |
| 193 | - * @deprecated 7.0.0 Use {@see Actors::get_public_key()}. | |
| 194 | - * | |
| 195 | - * @param int $user_id The WordPress User ID. | |
| 196 | - * @param bool $force Optional. Force the generation of a new key pair. Default false. | |
| 197 | - * | |
| 198 | - * @return string The public key. | |
| 128 | + * @return string The option key. | |
| 199 | 129 | */ |
| 200 | - public static function get_public_key_for( $user_id, $force = false ) { | |
| 201 | - \_deprecated_function( __METHOD__, '7.0.0', 'Activitypub\Collection\Actors::get_public_key' ); | |
| 130 | + protected static function get_signature_options_key_for( $user_id ) { | |
| 131 | + $id = $user_id; | |
| 202 | 132 | |
| 203 | - return Actors::get_public_key( $user_id, $force ); | |
| 204 | - } | |
| 133 | + if ( $user_id > 0 ) { | |
| 134 | + $user = \get_userdata( $user_id ); | |
| 135 | + // sanatize username because it could include spaces and special chars | |
| 136 | + $id = sanitize_title( $user->user_login ); | |
| 137 | + } | |
| 205 | 138 | |
| 206 | - /** | |
| 207 | - * Return the private key for a given user. | |
| 208 | - * | |
| 209 | - * @deprecated 7.0.0 Use {@see Actors::get_private_key()}. | |
| 210 | - * | |
| 211 | - * @param int $user_id The WordPress User ID. | |
| 212 | - * @param bool $force Optional. Force the generation of a new key pair. Default false. | |
| 213 | - * | |
| 214 | - * @return string The private key. | |
| 215 | - */ | |
| 216 | - public static function get_private_key_for( $user_id, $force = false ) { | |
| 217 | - \_deprecated_function( __METHOD__, '7.0.0', 'Activitypub\Collection\Actors::get_private_key' ); | |
| 218 | - | |
| 219 | - return Actors::get_private_key( $user_id, $force ); | |
| 139 | + return 'activitypub_keypair_for_' . $id; | |
| 220 | 140 | } |
| 221 | 141 | |
| 222 | 142 | /** |
| 223 | - * Return the key pair for a given user. | |
| 143 | + * Check if there is a legacy key pair | |
| 224 | 144 | * |
| 225 | - * @deprecated 7.0.0 Use {@see Actors::get_keypair()}. | |
| 226 | - * | |
| 227 | 145 | * @param int $user_id The WordPress User ID. |
| 228 | 146 | * |
| 229 | - * @return array The key pair. | |
| 147 | + * @return array|bool The key pair or false. | |
| 230 | 148 | */ |
| 231 | - public static function get_keypair_for( $user_id ) { | |
| 232 | - \_deprecated_function( __METHOD__, '7.0.0', 'Activitypub\Collection\Actors::get_keypair' ); | |
| 149 | + protected static function check_legacy_key_pair_for( $user_id ) { | |
| 150 | + switch ( $user_id ) { | |
| 151 | + case 0: | |
| 152 | + $public_key = \get_option( 'activitypub_blog_user_public_key' ); | |
| 153 | + $private_key = \get_option( 'activitypub_blog_user_private_key' ); | |
| 154 | + break; | |
| 155 | + case -1: | |
| 156 | + $public_key = \get_option( 'activitypub_application_user_public_key' ); | |
| 157 | + $private_key = \get_option( 'activitypub_application_user_private_key' ); | |
| 158 | + break; | |
| 159 | + default: | |
| 160 | + $public_key = \get_user_meta( $user_id, 'magic_sig_public_key', true ); | |
| 161 | + $private_key = \get_user_meta( $user_id, 'magic_sig_private_key', true ); | |
| 162 | + break; | |
| 163 | + } | |
| 233 | 164 | |
| 234 | - return Actors::get_keypair( $user_id ); | |
| 235 | - } | |
| 165 | + if ( ! empty( $public_key ) && is_string( $public_key ) && ! empty( $private_key ) && is_string( $private_key ) ) { | |
| 166 | + return array( | |
| 167 | + 'private_key' => $private_key, | |
| 168 | + 'public_key' => $public_key, | |
| 169 | + ); | |
| 170 | + } | |
| 236 | 171 | |
| 237 | - /** | |
| 238 | - * Get public key from key_id. | |
| 239 | - * | |
| 240 | - * @deprecated 7.4.0 Use {@see Remote_Actors::get_public_key()}. | |
| 241 | - * | |
| 242 | - * @param string $key_id The URL to the public key. | |
| 243 | - * | |
| 244 | - * @return resource|\WP_Error The public key resource or WP_Error. | |
| 245 | - */ | |
| 246 | - public static function get_remote_key( $key_id ) { | |
| 247 | - \_deprecated_function( __METHOD__, '7.4.0', 'Activitypub\Collection\Remote_Actors::get_public_key()' ); | |
| 248 | - | |
| 249 | - return Remote_Actors::get_public_key( $key_id ); | |
| 172 | + return false; | |
| 250 | 173 | } |
| 251 | 174 | |
| 252 | 175 | /** |
| 253 | - * Generates the Signature for an HTTP Request. | |
| 176 | + * Generates the Signature for a HTTP Request | |
| 254 | 177 | * |
| 255 | - * @deprecated 7.0.0 Use {@see Signature::sign_request()}. | |
| 256 | - * | |
| 257 | 178 | * @param int $user_id The WordPress User ID. |
| 258 | 179 | * @param string $http_method The HTTP method. |
| 259 | 180 | * @param string $url The URL to send the request to. |
| 260 | 181 | * @param string $date The date the request is sent. |
| 261 | - * @param string $digest Optional. The digest of the request body. Default null. | |
| 182 | + * @param string $digest The digest of the request body. | |
| 262 | 183 | * |
| 263 | 184 | * @return string The signature. |
| 264 | 185 | */ |
| 265 | 186 | public static function generate_signature( $user_id, $http_method, $url, $date, $digest = null ) { |
| 266 | - \_deprecated_function( __METHOD__, '7.0.0', self::class . '::sign_request()' ); | |
| 187 | + $user = Users::get_by_id( $user_id ); | |
| 188 | + $key = self::get_private_key_for( $user->get__id() ); | |
| 267 | 189 | |
| 268 | - $user = Actors::get_by_id( $user_id ); | |
| 269 | - $key = Actors::get_private_key( $user_id ); | |
| 270 | - | |
| 271 | 190 | $url_parts = \wp_parse_url( $url ); |
| 272 | 191 | |
| 273 | 192 | $host = $url_parts['host']; |
| 274 | 193 | $path = '/'; |
| 275 | 194 | |
| 276 | - // Add path. | |
| 195 | + // add path | |
| 277 | 196 | if ( ! empty( $url_parts['path'] ) ) { |
| 278 | 197 | $path = $url_parts['path']; |
| 279 | 198 | } |
| 280 | 199 | |
| 281 | - // Add query. | |
| 200 | + // add query | |
| 282 | 201 | if ( ! empty( $url_parts['query'] ) ) { |
| 283 | 202 | $path .= '?' . $url_parts['query']; |
| 284 | 203 | } |
| 285 | 204 | |
| @@ -292,11 +211,11 @@ | ||
| 292 | 211 | } |
| 293 | 212 | |
| 294 | 213 | $signature = null; |
| 295 | 214 | \openssl_sign( $signed_string, $signature, $key, \OPENSSL_ALGO_SHA256 ); |
| 296 | - $signature = \base64_encode( $signature ); // phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_encode | |
| 215 | + $signature = \base64_encode( $signature ); // phpcs:ignore | |
| 297 | 216 | |
| 298 | - $key_id = $user->get_id() . '#main-key'; | |
| 217 | + $key_id = $user->get_url() . '#main-key'; | |
| 299 | 218 | |
| 300 | 219 | if ( ! empty( $digest ) ) { |
| 301 | 220 | return \sprintf( 'keyId="%s",algorithm="rsa-sha256",headers="(request-target) host date digest",signature="%s"', $key_id, $signature ); |
| 302 | 221 | } else { |
| @@ -304,53 +223,145 @@ | ||
| 304 | 223 | } |
| 305 | 224 | } |
| 306 | 225 | |
| 307 | 226 | /** |
| 308 | - * Gets the signature algorithm from the signature header. | |
| 227 | + * Verifies the http signatures | |
| 309 | 228 | * |
| 310 | - * @deprecated 7.0.0 Use {@see Signature::verify()}. | |
| 229 | + * @param WP_REQUEST|array $request The request object or $_SERVER array. | |
| 311 | 230 | * |
| 312 | - * @param array $signature_block The signature block. | |
| 231 | + * @return mixed A boolean or WP_Error. | |
| 232 | + */ | |
| 233 | + public static function verify_http_signature( $request ) { | |
| 234 | + if ( is_object( $request ) ) { // REST Request object | |
| 235 | + // check if route starts with "index.php" | |
| 236 | + if ( str_starts_with( $request->get_route(), '/index.php' ) || ! rest_get_url_prefix() ) { | |
| 237 | + $route = $request->get_route(); | |
| 238 | + } else { | |
| 239 | + $route = '/' . rest_get_url_prefix() . '/' . ltrim( $request->get_route(), '/' ); | |
| 240 | + } | |
| 241 | + $headers = $request->get_headers(); | |
| 242 | + $headers['(request-target)'][0] = strtolower( $request->get_method() ) . ' ' . $route; | |
| 243 | + } else { | |
| 244 | + $request = self::format_server_request( $request ); | |
| 245 | + $headers = $request['headers']; // $_SERVER array | |
| 246 | + $headers['(request-target)'][0] = strtolower( $headers['request_method'][0] ) . ' ' . $headers['request_uri'][0]; | |
| 247 | + } | |
| 248 | + | |
| 249 | + if ( ! isset( $headers['signature'] ) ) { | |
| 250 | + return new WP_Error( 'activitypub_signature', 'Request not signed', array( 'status' => 403 ) ); | |
| 251 | + } | |
| 252 | + | |
| 253 | + if ( array_key_exists( 'signature', $headers ) ) { | |
| 254 | + $signature_block = self::parse_signature_header( $headers['signature'][0] ); | |
| 255 | + } elseif ( array_key_exists( 'authorization', $headers ) ) { | |
| 256 | + $signature_block = self::parse_signature_header( $headers['authorization'][0] ); | |
| 257 | + } | |
| 258 | + | |
| 259 | + if ( ! isset( $signature_block ) || ! $signature_block ) { | |
| 260 | + return new WP_Error( 'activitypub_signature', 'Incompatible request signature. keyId and signature are required', array( 'status' => 403 ) ); | |
| 261 | + } | |
| 262 | + | |
| 263 | + $signed_headers = $signature_block['headers']; | |
| 264 | + if ( ! $signed_headers ) { | |
| 265 | + $signed_headers = array( 'date' ); | |
| 266 | + } | |
| 267 | + | |
| 268 | + $signed_data = self::get_signed_data( $signed_headers, $signature_block, $headers ); | |
| 269 | + if ( ! $signed_data ) { | |
| 270 | + return new WP_Error( 'activitypub_signature', 'Signed request date outside acceptable time window', array( 'status' => 403 ) ); | |
| 271 | + } | |
| 272 | + | |
| 273 | + $algorithm = self::get_signature_algorithm( $signature_block ); | |
| 274 | + if ( ! $algorithm ) { | |
| 275 | + return new WP_Error( 'activitypub_signature', 'Unsupported signature algorithm (only rsa-sha256 and hs2019 are supported)', array( 'status' => 403 ) ); | |
| 276 | + } | |
| 277 | + | |
| 278 | + if ( \in_array( 'digest', $signed_headers, true ) && isset( $body ) ) { | |
| 279 | + if ( is_array( $headers['digest'] ) ) { | |
| 280 | + $headers['digest'] = $headers['digest'][0]; | |
| 281 | + } | |
| 282 | + $digest = explode( '=', $headers['digest'], 2 ); | |
| 283 | + if ( 'SHA-256' === $digest[0] ) { | |
| 284 | + $hashalg = 'sha256'; | |
| 285 | + } | |
| 286 | + if ( 'SHA-512' === $digest[0] ) { | |
| 287 | + $hashalg = 'sha512'; | |
| 288 | + } | |
| 289 | + | |
| 290 | + if ( \base64_encode( \hash( $hashalg, $body, true ) ) !== $digest[1] ) { // phpcs:ignore | |
| 291 | + return new WP_Error( 'activitypub_signature', 'Invalid Digest header', array( 'status' => 403 ) ); | |
| 292 | + } | |
| 293 | + } | |
| 294 | + | |
| 295 | + $public_key = self::get_remote_key( $signature_block['keyId'] ); | |
| 296 | + | |
| 297 | + if ( \is_wp_error( $public_key ) ) { | |
| 298 | + return $public_key; | |
| 299 | + } | |
| 300 | + | |
| 301 | + $verified = \openssl_verify( $signed_data, $signature_block['signature'], $public_key, $algorithm ) > 0; | |
| 302 | + | |
| 303 | + if ( ! $verified ) { | |
| 304 | + return new WP_Error( 'activitypub_signature', 'Invalid signature', array( 'status' => 403 ) ); | |
| 305 | + } | |
| 306 | + return $verified; | |
| 307 | + } | |
| 308 | + | |
| 309 | + /** | |
| 310 | + * Get public key from key_id | |
| 313 | 311 | * |
| 314 | - * @return string|bool The signature algorithm or false if not found. | |
| 312 | + * @param string $key_id The URL to the public key. | |
| 313 | + * | |
| 314 | + * @return WP_Error|string The public key. | |
| 315 | 315 | */ |
| 316 | - public static function get_signature_algorithm( $signature_block ) { // phpcs:ignore | |
| 317 | - \_deprecated_function( __METHOD__, '7.0.0', self::class . '::verify' ); | |
| 316 | + public static function get_remote_key( $key_id ) { // phpcs:ignore | |
| 317 | + $actor = get_remote_metadata_by_actor( strip_fragment_from_url( $key_id ) ); // phpcs:ignore | |
| 318 | + if ( \is_wp_error( $actor ) ) { | |
| 319 | + return $actor; | |
| 320 | + } | |
| 321 | + if ( isset( $actor['publicKey']['publicKeyPem'] ) ) { | |
| 322 | + return \rtrim( $actor['publicKey']['publicKeyPem'] ); // phpcs:ignore | |
| 323 | + } | |
| 324 | + return new WP_Error( 'activitypub_no_remote_key_found', 'No Public-Key found' ); | |
| 325 | + } | |
| 318 | 326 | |
| 319 | - if ( ! empty( $signature_block['algorithm'] ) ) { | |
| 327 | + /** | |
| 328 | + * Gets the signature algorithm from the signature header | |
| 329 | + * | |
| 330 | + * @param array $signature_block | |
| 331 | + * | |
| 332 | + * @return string The signature algorithm. | |
| 333 | + */ | |
| 334 | + public static function get_signature_algorithm( $signature_block ) { | |
| 335 | + if ( $signature_block['algorithm'] ) { | |
| 320 | 336 | switch ( $signature_block['algorithm'] ) { |
| 321 | 337 | case 'rsa-sha-512': |
| 322 | - return 'sha512'; // hs2019 https://datatracker.ietf.org/doc/html/draft-cavage-http-signatures-12. | |
| 338 | + return 'sha512'; //hs2019 https://datatracker.ietf.org/doc/html/draft-cavage-http-signatures-12 | |
| 323 | 339 | default: |
| 324 | 340 | return 'sha256'; |
| 325 | 341 | } |
| 326 | 342 | } |
| 327 | - | |
| 328 | 343 | return false; |
| 329 | 344 | } |
| 330 | 345 | |
| 331 | 346 | /** |
| 332 | - * Parses the Signature header. | |
| 347 | + * Parses the Signature header | |
| 333 | 348 | * |
| 334 | - * @deprecated 7.0.0 Use {@see Signature::verify()}. | |
| 335 | - * | |
| 336 | 349 | * @param string $signature The signature header. |
| 337 | 350 | * |
| 338 | - * @return array Signature parts. | |
| 351 | + * @return array signature parts | |
| 339 | 352 | */ |
| 340 | - public static function parse_signature_header( $signature ) { // phpcs:ignore | |
| 341 | - \_deprecated_function( __METHOD__, '7.0.0', self::class . '::verify' ); | |
| 353 | + public static function parse_signature_header( $signature ) { | |
| 354 | + $parsed_header = array(); | |
| 355 | + $matches = array(); | |
| 342 | 356 | |
| 343 | - $parsed_header = array(); | |
| 344 | - $matches = array(); | |
| 345 | - | |
| 346 | 357 | if ( \preg_match( '/keyId="(.*?)"/ism', $signature, $matches ) ) { |
| 347 | 358 | $parsed_header['keyId'] = trim( $matches[1] ); |
| 348 | 359 | } |
| 349 | - if ( \preg_match( '/created=["|\']*([0-9]*)["|\']*/ism', $signature, $matches ) ) { | |
| 360 | + if ( \preg_match( '/created=([0-9]*)/ism', $signature, $matches ) ) { | |
| 350 | 361 | $parsed_header['(created)'] = trim( $matches[1] ); |
| 351 | 362 | } |
| 352 | - if ( \preg_match( '/expires=["|\']*([0-9]*)["|\']*/ism', $signature, $matches ) ) { | |
| 363 | + if ( \preg_match( '/expires=([0-9]*)/ism', $signature, $matches ) ) { | |
| 353 | 364 | $parsed_header['(expires)'] = trim( $matches[1] ); |
| 354 | 365 | } |
| 355 | 366 | if ( \preg_match( '/algorithm="(.*?)"/ism', $signature, $matches ) ) { |
| 356 | 367 | $parsed_header['algorithm'] = trim( $matches[1] ); |
| @@ -358,12 +369,12 @@ | ||
| 358 | 369 | if ( \preg_match( '/headers="(.*?)"/ism', $signature, $matches ) ) { |
| 359 | 370 | $parsed_header['headers'] = \explode( ' ', trim( $matches[1] ) ); |
| 360 | 371 | } |
| 361 | 372 | if ( \preg_match( '/signature="(.*?)"/ism', $signature, $matches ) ) { |
| 362 | - $parsed_header['signature'] = \base64_decode( preg_replace( '/\s+/', '', trim( $matches[1] ) ) ); // phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_decode | |
| 373 | + $parsed_header['signature'] = \base64_decode( preg_replace( '/\s+/', '', trim( $matches[1] ) ) ); // phpcs:ignore | |
| 363 | 374 | } |
| 364 | 375 | |
| 365 | - if ( empty( $parsed_header['headers'] ) ) { | |
| 376 | + if ( ( $parsed_header['signature'] ) && ( $parsed_header['algorithm'] ) && ( ! $parsed_header['headers'] ) ) { | |
| 366 | 377 | $parsed_header['headers'] = array( 'date' ); |
| 367 | 378 | } |
| 368 | 379 | |
| 369 | 380 | return $parsed_header; |
| @@ -369,23 +380,18 @@ | ||
| 369 | 380 | return $parsed_header; |
| 370 | 381 | } |
| 371 | 382 | |
| 372 | 383 | /** |
| 373 | - * Gets the header data from the included pseudo headers. | |
| 384 | + * Gets the header data from the included pseudo headers | |
| 374 | 385 | * |
| 375 | - * @deprecated 7.0.0 Use {@see Signature::verify()}. | |
| 376 | - * | |
| 377 | 386 | * @param array $signed_headers The signed headers. |
| 378 | - * @param array $signature_block The signature block. | |
| 379 | - * @param array $headers The HTTP headers. | |
| 387 | + * @param array $signature_block (pseudo-headers) | |
| 388 | + * @param array $headers (http headers) | |
| 380 | 389 | * |
| 381 | 390 | * @return string signed headers for comparison |
| 382 | 391 | */ |
| 383 | - public static function get_signed_data( $signed_headers, $signature_block, $headers ) { // phpcs:ignore | |
| 384 | - \_deprecated_function( __METHOD__, '7.0.0', self::class . '::verify' ); | |
| 385 | - | |
| 392 | + public static function get_signed_data( $signed_headers, $signature_block, $headers ) { | |
| 386 | 393 | $signed_data = ''; |
| 387 | - | |
| 388 | 394 | // This also verifies time-based values by returning false if any of these are out of range. |
| 389 | 395 | foreach ( $signed_headers as $header ) { |
| 390 | 396 | if ( 'host' === $header ) { |
| 391 | 397 | if ( isset( $headers['x_original_host'] ) ) { |
| @@ -402,166 +408,71 @@ | ||
| 402 | 408 | continue; |
| 403 | 409 | } |
| 404 | 410 | if ( '(created)' === $header ) { |
| 405 | 411 | if ( ! empty( $signature_block['(created)'] ) && \intval( $signature_block['(created)'] ) > \time() ) { |
| 406 | - // Created in the future. | |
| 412 | + // created in future | |
| 407 | 413 | return false; |
| 408 | 414 | } |
| 409 | - | |
| 410 | - if ( ! array_key_exists( '(created)', $headers ) ) { | |
| 411 | - $signed_data .= $header . ': ' . $signature_block['(created)'] . "\n"; | |
| 412 | - continue; | |
| 413 | - } | |
| 414 | 415 | } |
| 415 | 416 | if ( '(expires)' === $header ) { |
| 416 | 417 | if ( ! empty( $signature_block['(expires)'] ) && \intval( $signature_block['(expires)'] ) < \time() ) { |
| 417 | - // Expired in the past. | |
| 418 | + // expired in past | |
| 418 | 419 | return false; |
| 419 | 420 | } |
| 420 | - | |
| 421 | - if ( ! array_key_exists( '(expires)', $headers ) ) { | |
| 422 | - $signed_data .= $header . ': ' . $signature_block['(expires)'] . "\n"; | |
| 423 | - continue; | |
| 424 | - } | |
| 425 | 421 | } |
| 426 | 422 | if ( 'date' === $header ) { |
| 427 | - // A signed `date` header with no value must fail closed, otherwise the time-window check is skipped. | |
| 428 | - if ( empty( $headers[ $header ][0] ) ) { | |
| 429 | - return false; | |
| 430 | - } | |
| 423 | + // allow a bit of leeway for misconfigured clocks. | |
| 424 | + $d = new DateTime( $headers[ $header ][0] ); | |
| 425 | + $d->setTimeZone( new DateTimeZone( 'UTC' ) ); | |
| 426 | + $c = $d->format( 'U' ); | |
| 431 | 427 | |
| 432 | - // date_create() returns false on malformed input; new DateTime() would instead throw. | |
| 433 | - $d = \date_create( $headers[ $header ][0], new \DateTimeZone( 'UTC' ) ); | |
| 434 | - if ( false === $d ) { | |
| 435 | - return false; | |
| 436 | - } | |
| 437 | - $d->setTimeZone( new \DateTimeZone( 'UTC' ) ); | |
| 438 | - $c = (int) $d->format( 'U' ); | |
| 428 | + $dplus = time() + ( 3 * HOUR_IN_SECONDS ); | |
| 429 | + $dminus = time() - ( 3 * HOUR_IN_SECONDS ); | |
| 439 | 430 | |
| 440 | - // Match the past-skew of the maintained Http_Signature_Draft verifier (1 hour); use its 5-minute future allowance. | |
| 441 | - $now = \time(); | |
| 442 | - $d_plus = $now + ( 5 * MINUTE_IN_SECONDS ); | |
| 443 | - $d_minus = $now - HOUR_IN_SECONDS; | |
| 444 | - | |
| 445 | - if ( $c > $d_plus || $c < $d_minus ) { | |
| 446 | - // Time out of range. | |
| 431 | + if ( $c > $dplus || $c < $dminus ) { | |
| 432 | + // time out of range | |
| 447 | 433 | return false; |
| 448 | 434 | } |
| 449 | 435 | } |
| 450 | - | |
| 451 | - if ( ! empty( $headers[ $header ][0] ) ) { | |
| 452 | - $signed_data .= $header . ': ' . $headers[ $header ][0] . "\n"; | |
| 453 | - } | |
| 436 | + $signed_data .= $header . ': ' . $headers[ $header ][0] . "\n"; | |
| 454 | 437 | } |
| 455 | - | |
| 456 | 438 | return \rtrim( $signed_data, "\n" ); |
| 457 | 439 | } |
| 458 | 440 | |
| 459 | 441 | /** |
| 460 | - * Generates the digest for an HTTP Request. | |
| 442 | + * Generates the digest for a HTTP Request | |
| 461 | 443 | * |
| 462 | - * @deprecated 7.0.0 Use {@see Signature::sign_request()}. | |
| 463 | - * | |
| 464 | 444 | * @param string $body The body of the request. |
| 465 | 445 | * |
| 466 | 446 | * @return string The digest. |
| 467 | 447 | */ |
| 468 | 448 | public static function generate_digest( $body ) { |
| 469 | - \_deprecated_function( __METHOD__, '7.0.0', self::class . '::sign_request' ); | |
| 470 | - | |
| 471 | - $digest = \base64_encode( \hash( 'sha256', $body, true ) ); // phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_encode | |
| 449 | + $digest = \base64_encode( \hash( 'sha256', $body, true ) ); // phpcs:ignore | |
| 472 | 450 | return "SHA-256=$digest"; |
| 473 | 451 | } |
| 474 | 452 | |
| 475 | 453 | /** |
| 476 | - * Compute the collection digest for a specific instance. | |
| 454 | + * Formats the $_SERVER to resemble the WP_REST_REQUEST array, | |
| 455 | + * for use with verify_http_signature() | |
| 477 | 456 | * |
| 478 | - * Implements FEP-8fcf: Followers collection synchronization. | |
| 479 | - * The digest is created by XORing together the individual SHA256 digests | |
| 480 | - * of each follower's ID. | |
| 457 | + * @param array $_SERVER The $_SERVER array. | |
| 481 | 458 | * |
| 482 | - * @see https://codeberg.org/fediverse/fep/src/branch/main/fep/8fcf/fep-8fcf.md | |
| 483 | - * | |
| 484 | - * @param array $collection The user ID whose followers to compute. | |
| 485 | - * | |
| 486 | - * @return string|false The hex-encoded digest, or false if no followers. | |
| 459 | + * @return array $request The formatted request array. | |
| 487 | 460 | */ |
| 488 | - public static function get_collection_digest( $collection ) { | |
| 489 | - if ( empty( $collection ) || ! is_array( $collection ) ) { | |
| 490 | - return false; | |
| 491 | - } | |
| 492 | - | |
| 493 | - // Initialize with zeros (64 hex chars = 32 bytes = 256 bits). | |
| 494 | - $digest = str_repeat( '0', 64 ); | |
| 495 | - | |
| 496 | - foreach ( $collection as $item ) { | |
| 497 | - // Compute SHA256 hash of the follower ID. | |
| 498 | - $hash = hash( 'sha256', $item ); | |
| 499 | - | |
| 500 | - // XOR the hash with the running digest. | |
| 501 | - $digest = self::xor_hex_strings( $digest, $hash ); | |
| 502 | - } | |
| 503 | - | |
| 504 | - return $digest; | |
| 505 | - } | |
| 506 | - | |
| 507 | - /** | |
| 508 | - * XOR two hexadecimal strings. | |
| 509 | - * | |
| 510 | - * Used for FEP-8fcf digest computation. | |
| 511 | - * | |
| 512 | - * @param string $hex1 First hex string. | |
| 513 | - * @param string $hex2 Second hex string. | |
| 514 | - * | |
| 515 | - * @return string The XORed result as a hex string. | |
| 516 | - */ | |
| 517 | - public static function xor_hex_strings( $hex1, $hex2 ) { | |
| 518 | - $result = ''; | |
| 519 | - | |
| 520 | - // Ensure both strings are the same length (should be 64 chars for SHA256). | |
| 521 | - $length = \max( \strlen( $hex1 ), \strlen( $hex2 ) ); | |
| 522 | - $hex1 = \str_pad( $hex1, $length, '0', STR_PAD_LEFT ); | |
| 523 | - $hex2 = \str_pad( $hex2, $length, '0', STR_PAD_LEFT ); | |
| 524 | - | |
| 525 | - // XOR each pair of hex digits. | |
| 526 | - for ( $i = 0; $i < $length; $i += 2 ) { | |
| 527 | - $byte1 = \hexdec( \substr( $hex1, $i, 2 ) ); | |
| 528 | - $byte2 = \hexdec( \substr( $hex2, $i, 2 ) ); | |
| 529 | - $result .= \str_pad( \dechex( $byte1 ^ $byte2 ), 2, '0', STR_PAD_LEFT ); | |
| 530 | - } | |
| 531 | - | |
| 532 | - return $result; | |
| 533 | - } | |
| 534 | - | |
| 535 | - /** | |
| 536 | - * Parse a Collection-Synchronization header (FEP-8fcf). | |
| 537 | - * | |
| 538 | - * Parses the signature-style format used by the Collection-Synchronization header. | |
| 539 | - * | |
| 540 | - * @see https://codeberg.org/fediverse/fep/src/branch/main/fep/8fcf/fep-8fcf.md | |
| 541 | - * | |
| 542 | - * @param string $header The header value. | |
| 543 | - * | |
| 544 | - * @return array|false Array with parsed parameters (collectionId, url, digest), or false on failure. | |
| 545 | - */ | |
| 546 | - public static function parse_collection_sync_header( $header ) { | |
| 547 | - if ( empty( $header ) ) { | |
| 548 | - return false; | |
| 549 | - } | |
| 550 | - | |
| 551 | - // Parse the signature-style format: key="value", key="value". | |
| 552 | - $params = array(); | |
| 553 | - | |
| 554 | - if ( \preg_match_all( '/(\w+)="([^"]*)"/', $header, $matches, PREG_SET_ORDER ) ) { | |
| 555 | - foreach ( $matches as $match ) { | |
| 556 | - $params[ $match[1] ] = $match[2]; | |
| 461 | + public static function format_server_request( $server ) { | |
| 462 | + $request = array(); | |
| 463 | + foreach ( $server as $param_key => $param_val ) { | |
| 464 | + $req_param = strtolower( $param_key ); | |
| 465 | + if ( 'REQUEST_URI' === $req_param ) { | |
| 466 | + $request['headers']['route'][] = $param_val; | |
| 467 | + } else { | |
| 468 | + $header_key = str_replace( | |
| 469 | + 'http_', | |
| 470 | + '', | |
| 471 | + $req_param | |
| 472 | + ); | |
| 473 | + $request['headers'][ $header_key ][] = \wp_unslash( $param_val ); | |
| 557 | 474 | } |
| 558 | 475 | } |
| 559 | - | |
| 560 | - // Validate required fields for FEP-8fcf. | |
| 561 | - if ( empty( $params['collectionId'] ) || empty( $params['url'] ) || empty( $params['digest'] ) ) { | |
| 562 | - return false; | |
| 563 | - } | |
| 564 | - | |
| 565 | - return $params; | |
| 476 | + return $request; | |
| 566 | 477 | } |
| 567 | 478 | } |
