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| 1 | <?php |
| 2 | |
| 3 | namespace MediaWiki\Extension\SecurePoll\Crypt; |
| 4 | |
| 5 | use JsonException; |
| 6 | use MediaWiki\Extension\SecurePoll\Context; |
| 7 | use MediaWiki\Extension\SecurePoll\Entities\Election; |
| 8 | use MediaWiki\Message\Message; |
| 9 | use MediaWiki\SpecialPage\SpecialPage; |
| 10 | use MediaWiki\Status\Status; |
| 11 | use OpenSSLAsymmetricKey; |
| 12 | use RuntimeException; |
| 13 | use Wikimedia\Rdbms\IDatabase; |
| 14 | |
| 15 | /** |
| 16 | * Cryptography module that uses the PHP openssl extension. |
| 17 | * At the moment, only RSA keys are supported, with a minimum size of 2048 bits. |
| 18 | * |
| 19 | * Election properties used: |
| 20 | * openssl-encrypt-key: The public key used for encrypting. |
| 21 | * openssl-sign-key: The private key used for signing. |
| 22 | * openssl-decrypt-key: The private key used for decrypting. |
| 23 | * openssl-verify-key: The public ky used for verification. |
| 24 | * |
| 25 | * Generally only openssl-encrypt-key and openssl-sign-key are required for voting, |
| 26 | * openssl-decrypt-key and openssl-verify-key are for tallying. |
| 27 | */ |
| 28 | class OpenSslCrypt extends Crypt { |
| 29 | private const CLAIM_TYPE_TOKEN_TYPE = 'typ'; |
| 30 | private const CLAIM_TYPE_SIGNATURE_ALGORITHM = 'alg'; |
| 31 | private const CLAIM_TYPE_ISSUER = 'iss'; |
| 32 | private const CLAIM_TYPE_SUBJECT = 'sub'; |
| 33 | private const CLAIM_TYPE_VOTE = 'mw-ext-sp-vot'; |
| 34 | private const CLAIM_TYPE_ENCRYPT_ALGORITHM = 'mw-ext-sp-alg'; |
| 35 | private const CLAIM_TYPE_ENVELOPE_KEY = 'mw-ext-sp-env'; |
| 36 | private const CLAIM_TYPE_TAG = 'mw-ext-sp-tag'; |
| 37 | private const CLAIM_TYPE_IV = 'mw-ext-sp-iv'; |
| 38 | private const CLAIM_TYPE_MAC = 'mw-ext-sp-mac'; |
| 39 | |
| 40 | /** @var Context|null */ |
| 41 | private $context; |
| 42 | |
| 43 | /** @var Election|null */ |
| 44 | private $election; |
| 45 | |
| 46 | /** @var OpenSSLAsymmetricKey|resource|null */ |
| 47 | private $encryptKey = null; |
| 48 | |
| 49 | /** @var OpenSSLAsymmetricKey|resource|null */ |
| 50 | private $signKey = null; |
| 51 | |
| 52 | /** @var OpenSSLAsymmetricKey|resource|null */ |
| 53 | private $decryptKey = null; |
| 54 | |
| 55 | /** @var OpenSSLAsymmetricKey|resource|null */ |
| 56 | private $verifyKey = null; |
| 57 | |
| 58 | /** |
| 59 | * Constructor. |
| 60 | * @param Context|null $context |
| 61 | * @param Election|null $election |
| 62 | */ |
| 63 | public function __construct( $context, $election ) { |
| 64 | if ( !extension_loaded( 'openssl' ) ) { |
| 65 | throw new RuntimeException( 'The openssl extension must be enabled in php.ini to use this class' ); |
| 66 | } |
| 67 | |
| 68 | $this->context = $context; |
| 69 | $this->election = $election; |
| 70 | } |
| 71 | |
| 72 | /** |
| 73 | * Encrypt some data. When successful, the value member of the Status object |
| 74 | * will contain the encrypted record. |
| 75 | * @param string $record |
| 76 | * @return Status |
| 77 | */ |
| 78 | public function encrypt( $record ) { |
| 79 | $status = $this->setupKeys(); |
| 80 | if ( !$status->isOK() ) { |
| 81 | $this->cleanup(); |
| 82 | return $status; |
| 83 | } |
| 84 | |
| 85 | if ( $this->encryptKey === null || $this->signKey === null ) { |
| 86 | return Status::newFatal( 'securepoll-openssl-invalid-key' ); |
| 87 | } |
| 88 | |
| 89 | $cipherAlg = 'aes-256-gcm'; |
| 90 | $keyLength = 32; |
| 91 | $signAlg = 'RS256'; |
| 92 | $hashAlg = 'sha256'; |
| 93 | |
| 94 | $this->clearErrors(); |
| 95 | $ivLength = openssl_cipher_iv_length( $cipherAlg ); |
| 96 | if ( $ivLength === false ) { |
| 97 | return $this->getErrorStatus( 'openssl_cipher_iv_length' ); |
| 98 | } |
| 99 | |
| 100 | $iv = random_bytes( $ivLength ); |
| 101 | $tag = ''; |
| 102 | $secretKey = random_bytes( $keyLength ); |
| 103 | |
| 104 | // authenticate vote metadata with our secret key, as otherwise in scenarios |
| 105 | // where the signing key is compromised or doesn't exist, the metadata could be forged/changed |
| 106 | $issuedBy = self::getIssuer(); |
| 107 | $subject = (string)$this->election->getId(); |
| 108 | $aad = $issuedBy . '|' . $subject; |
| 109 | |
| 110 | $this->clearErrors(); |
| 111 | $ciphertext = openssl_encrypt( |
| 112 | $record, |
| 113 | $cipherAlg, |
| 114 | $secretKey, |
| 115 | OPENSSL_RAW_DATA, |
| 116 | $iv, |
| 117 | $tag, |
| 118 | $aad, |
| 119 | 16 |
| 120 | ); |
| 121 | |
| 122 | if ( $ciphertext === false ) { |
| 123 | return $this->getErrorStatus( 'openssl_encrypt' ); |
| 124 | } |
| 125 | |
| 126 | $this->clearErrors(); |
| 127 | $result = openssl_public_encrypt( |
| 128 | $secretKey, |
| 129 | $envelopeKey, |
| 130 | $this->encryptKey, |
| 131 | OPENSSL_PKCS1_OAEP_PADDING |
| 132 | ); |
| 133 | |
| 134 | if ( !$result ) { |
| 135 | return $this->getErrorStatus( 'openssl_public_encrypt' ); |
| 136 | } |
| 137 | |
| 138 | $header = [ |
| 139 | self::CLAIM_TYPE_SIGNATURE_ALGORITHM => $signAlg, |
| 140 | self::CLAIM_TYPE_TOKEN_TYPE => 'JWT' |
| 141 | ]; |
| 142 | |
| 143 | $claims = [ |
| 144 | self::CLAIM_TYPE_ISSUER => $issuedBy, |
| 145 | self::CLAIM_TYPE_SUBJECT => $subject, |
| 146 | self::CLAIM_TYPE_VOTE => base64_encode( $ciphertext ), |
| 147 | self::CLAIM_TYPE_ENCRYPT_ALGORITHM => $cipherAlg, |
| 148 | self::CLAIM_TYPE_ENVELOPE_KEY => base64_encode( $envelopeKey ), |
| 149 | self::CLAIM_TYPE_TAG => base64_encode( $tag ), |
| 150 | self::CLAIM_TYPE_IV => base64_encode( $iv ), |
| 151 | self::CLAIM_TYPE_MAC => hash_hmac( 'sha256', $envelopeKey, $secretKey ), |
| 152 | ]; |
| 153 | |
| 154 | $jwt = $this->jwtEncode( $header ) . '.' . $this->jwtEncode( $claims ); |
| 155 | $this->clearErrors(); |
| 156 | $result = openssl_sign( $jwt, $sig, $this->signKey, $hashAlg ); |
| 157 | if ( !$result ) { |
| 158 | return $this->getErrorStatus( 'openssl_sign' ); |
| 159 | } |
| 160 | |
| 161 | $jwt .= '.' . $this->jwtEncode( $sig ); |
| 162 | |
| 163 | return Status::newGood( $jwt ); |
| 164 | } |
| 165 | |
| 166 | /** |
| 167 | * Decrypt some data. When successful, the value member of the Status object |
| 168 | * will contain the encrypted record. |
| 169 | * |
| 170 | * This may be run in an offline scenario with no access to the public encryption |
| 171 | * key or private signing key. This method requires the private decryption key and |
| 172 | * public verification key to be supplied via the decryption data. |
| 173 | * |
| 174 | * @param string $record |
| 175 | * @return Status |
| 176 | */ |
| 177 | public function decrypt( $record ) { |
| 178 | $status = $this->setupKeys(); |
| 179 | if ( !$status->isOK() ) { |
| 180 | $this->cleanup(); |
| 181 | return $status; |
| 182 | } |
| 183 | |
| 184 | if ( $this->decryptKey === null ) { |
| 185 | return Status::newFatal( 'securepoll-no-decryption-key' ); |
| 186 | } |
| 187 | |
| 188 | if ( $this->verifyKey === null ) { |
| 189 | return Status::newFatal( 'securepoll-no-verification-key' ); |
| 190 | } |
| 191 | |
| 192 | // $record may contain a leading line break in dump-based tallying, so trim it out before verifying the JWT |
| 193 | $parts = explode( '.', trim( $record ) ); |
| 194 | if ( count( $parts ) !== 3 ) { |
| 195 | return $this->getErrorStatus( 'verify_jwt', 'jwt does not contain exactly 3 parts' ); |
| 196 | } |
| 197 | |
| 198 | try { |
| 199 | $header = $this->jwtDecode( $parts[0] ); |
| 200 | $claims = $this->jwtDecode( $parts[1] ); |
| 201 | $sig = $this->jwtDecode( $parts[2], false ); |
| 202 | } catch ( JsonException $e ) { |
| 203 | return $this->getErrorStatus( 'verify_jwt', $e->getMessage() ); |
| 204 | } |
| 205 | |
| 206 | if ( $header[self::CLAIM_TYPE_SIGNATURE_ALGORITHM] === 'RS256' ) { |
| 207 | $hashAlg = 'sha256'; |
| 208 | } else { |
| 209 | return $this->getErrorStatus( 'verify_jwt', 'jwt header alg is not RS256' ); |
| 210 | } |
| 211 | |
| 212 | $requiredClaims = [ |
| 213 | self::CLAIM_TYPE_ISSUER, |
| 214 | self::CLAIM_TYPE_SUBJECT, |
| 215 | self::CLAIM_TYPE_VOTE, |
| 216 | self::CLAIM_TYPE_ENCRYPT_ALGORITHM, |
| 217 | self::CLAIM_TYPE_ENVELOPE_KEY, |
| 218 | self::CLAIM_TYPE_TAG, |
| 219 | self::CLAIM_TYPE_IV, |
| 220 | self::CLAIM_TYPE_MAC, |
| 221 | ]; |
| 222 | foreach ( $requiredClaims as $claim ) { |
| 223 | if ( !isset( $claims[$claim] ) || !is_string( $claims[$claim] ) || $claims[$claim] === '' ) { |
| 224 | return $this->getErrorStatus( 'verify_jwt', "jwt missing claim $claim" ); |
| 225 | } |
| 226 | } |
| 227 | |
| 228 | $data = $parts[0] . '.' . $parts[1]; |
| 229 | $this->clearErrors(); |
| 230 | $result = openssl_verify( $data, $sig, $this->verifyKey, $hashAlg ); |
| 231 | if ( $result === false || $result === -1 ) { |
| 232 | return $this->getErrorStatus( 'openssl_verify' ); |
| 233 | } elseif ( $result === 0 ) { |
| 234 | return $this->getErrorStatus( 'verify_jwt', 'invalid signature' ); |
| 235 | } |
| 236 | |
| 237 | if ( $claims[self::CLAIM_TYPE_ISSUER] !== self::getIssuer() |
| 238 | || $claims[self::CLAIM_TYPE_SUBJECT] !== (string)$this->election->getId() |
| 239 | ) { |
| 240 | return $this->getErrorStatus( 'verify_jwt', 'jwt is not for the current election' ); |
| 241 | } |
| 242 | |
| 243 | if ( !in_array( $claims[self::CLAIM_TYPE_ENCRYPT_ALGORITHM], openssl_get_cipher_methods() ) ) { |
| 244 | return $this->getErrorStatus( 'decrypt_vote', 'vote encryption algorithm not supported' ); |
| 245 | } |
| 246 | |
| 247 | $decoded = [ |
| 248 | self::CLAIM_TYPE_VOTE => false, |
| 249 | self::CLAIM_TYPE_ENVELOPE_KEY => false, |
| 250 | self::CLAIM_TYPE_IV => false, |
| 251 | self::CLAIM_TYPE_TAG => false |
| 252 | ]; |
| 253 | '@phan-var array<string,string|false> $decoded'; |
| 254 | |
| 255 | foreach ( $decoded as $claim => &$value ) { |
| 256 | $value = base64_decode( $claims[$claim], true ); |
| 257 | if ( $value === false ) { |
| 258 | return $this->getErrorStatus( 'decrypt_vote', "invalid base64 in $claim" ); |
| 259 | } |
| 260 | } |
| 261 | |
| 262 | $this->clearErrors(); |
| 263 | $result = openssl_private_decrypt( |
| 264 | $decoded[self::CLAIM_TYPE_ENVELOPE_KEY], |
| 265 | $secretKey, |
| 266 | $this->decryptKey, |
| 267 | OPENSSL_PKCS1_OAEP_PADDING |
| 268 | ); |
| 269 | |
| 270 | if ( !$result ) { |
| 271 | return $this->getErrorStatus( 'openssl_private_decrypt' ); |
| 272 | } |
| 273 | |
| 274 | $mac = hash_hmac( 'sha256', $decoded[self::CLAIM_TYPE_ENVELOPE_KEY], $secretKey ); |
| 275 | if ( !hash_equals( $claims[self::CLAIM_TYPE_MAC], $mac ) ) { |
| 276 | $this->cleanup(); |
| 277 | return Status::newFatal( 'securepoll-wrong-decryption-key' ); |
| 278 | } |
| 279 | |
| 280 | $aad = $claims['iss'] . '|' . $claims['sub']; |
| 281 | $this->clearErrors(); |
| 282 | $vote = openssl_decrypt( |
| 283 | $decoded[self::CLAIM_TYPE_VOTE], |
| 284 | $claims[self::CLAIM_TYPE_ENCRYPT_ALGORITHM], |
| 285 | $secretKey, |
| 286 | OPENSSL_RAW_DATA, |
| 287 | $decoded[self::CLAIM_TYPE_IV], |
| 288 | $decoded[self::CLAIM_TYPE_TAG], |
| 289 | $aad |
| 290 | ); |
| 291 | |
| 292 | if ( $vote === false ) { |
| 293 | return $this->getErrorStatus( 'openssl_decrypt' ); |
| 294 | } |
| 295 | |
| 296 | return Status::newGood( $vote ); |
| 297 | } |
| 298 | |
| 299 | /** |
| 300 | * @param string $prefix Prefix for error message |
| 301 | * @param ?string $error Error message, or null to use openssl_error_string() |
| 302 | * @return Status |
| 303 | */ |
| 304 | private function getErrorStatus( string $prefix, ?string $error = null ): Status { |
| 305 | global $wgSecurePollShowErrorDetail; |
| 306 | |
| 307 | $error ??= openssl_error_string(); |
| 308 | $this->cleanup(); |
| 309 | wfDebug( "$prefix:$error" ); |
| 310 | |
| 311 | if ( $wgSecurePollShowErrorDetail ) { |
| 312 | return Status::newFatal( 'securepoll-full-openssl-error', "$prefix:$error" ); |
| 313 | } else { |
| 314 | return Status::newFatal( 'securepoll-secret-openssl-error' ); |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | /** |
| 319 | * Load our keys from the election store. |
| 320 | * Keys that do not exist in the store will remain null, however if a private key is supplied |
| 321 | * but not its corresponding public key, we will derive it. |
| 322 | * |
| 323 | * @return Status |
| 324 | */ |
| 325 | private function setupKeys(): Status { |
| 326 | if ( $this->decryptKey === null ) { |
| 327 | $decryptKey = $this->context->decryptData['openssl-decrypt-key'] ?? |
| 328 | strval( $this->election->getProperty( 'openssl-decrypt-key' ) ); |
| 329 | if ( $decryptKey !== '' ) { |
| 330 | $this->clearErrors(); |
| 331 | $result = openssl_pkey_get_private( $decryptKey ); |
| 332 | if ( $result === false ) { |
| 333 | return $this->getErrorStatus( 'openssl_pkey_get_private' ); |
| 334 | } |
| 335 | |
| 336 | $this->decryptKey = $result; |
| 337 | } |
| 338 | } |
| 339 | |
| 340 | if ( $this->encryptKey === null ) { |
| 341 | $encryptKey = strval( $this->election->getProperty( 'openssl-encrypt-key' ) ); |
| 342 | if ( $encryptKey === '' && $this->decryptKey !== null ) { |
| 343 | $this->clearErrors(); |
| 344 | $result = openssl_pkey_get_details( $this->decryptKey ); |
| 345 | if ( $result === false ) { |
| 346 | return $this->getErrorStatus( 'openssl_pkey_get_details' ); |
| 347 | } |
| 348 | |
| 349 | $encryptKey = $result['key']; |
| 350 | } |
| 351 | |
| 352 | if ( $encryptKey !== '' ) { |
| 353 | $this->clearErrors(); |
| 354 | $result = openssl_pkey_get_public( $encryptKey ); |
| 355 | if ( $result === false ) { |
| 356 | return $this->getErrorStatus( 'openssl_pkey_get_public' ); |
| 357 | } |
| 358 | |
| 359 | $this->encryptKey = $result; |
| 360 | |
| 361 | $this->clearErrors(); |
| 362 | $keyDetails = openssl_pkey_get_details( $this->encryptKey ); |
| 363 | if ( $keyDetails === false ) { |
| 364 | return $this->getErrorStatus( 'openssl_pkey_get_details' ); |
| 365 | } |
| 366 | |
| 367 | if ( $keyDetails['type'] !== OPENSSL_KEYTYPE_RSA ) { |
| 368 | return $this->getErrorStatus( 'setup_keys', 'encryption key is not RSA' ); |
| 369 | } |
| 370 | |
| 371 | if ( $keyDetails['bits'] < 2048 ) { |
| 372 | return $this->getErrorStatus( 'setup_keys', 'encryption key is weaker than 2048 bits' ); |
| 373 | } |
| 374 | } |
| 375 | } |
| 376 | |
| 377 | if ( $this->signKey === null ) { |
| 378 | $signKey = strval( $this->election->getProperty( 'openssl-sign-key' ) ); |
| 379 | if ( $signKey !== '' ) { |
| 380 | $this->clearErrors(); |
| 381 | $result = openssl_pkey_get_private( $signKey ); |
| 382 | if ( $result === false ) { |
| 383 | return $this->getErrorStatus( 'openssl_pkey_get_private' ); |
| 384 | } |
| 385 | |
| 386 | $this->signKey = $result; |
| 387 | |
| 388 | $this->clearErrors(); |
| 389 | $keyDetails = openssl_pkey_get_details( $this->signKey ); |
| 390 | if ( $keyDetails === false ) { |
| 391 | return $this->getErrorStatus( 'openssl_pkey_get_details' ); |
| 392 | } |
| 393 | |
| 394 | if ( $keyDetails['type'] !== OPENSSL_KEYTYPE_RSA ) { |
| 395 | return $this->getErrorStatus( 'setup_keys', 'signing key is not RSA' ); |
| 396 | } |
| 397 | |
| 398 | if ( $keyDetails['bits'] < 2048 ) { |
| 399 | return $this->getErrorStatus( 'setup_keys', 'signing key is weaker than 2048 bits' ); |
| 400 | } |
| 401 | } |
| 402 | } |
| 403 | |
| 404 | if ( $this->verifyKey === null ) { |
| 405 | $verifyKey = $this->context->decryptData['openssl-verify-key'] ?? |
| 406 | strval( $this->election->getProperty( 'openssl-verify-key' ) ); |
| 407 | if ( $verifyKey === '' && $this->signKey !== null ) { |
| 408 | $this->clearErrors(); |
| 409 | $result = openssl_pkey_get_details( $this->signKey ); |
| 410 | if ( $result === false ) { |
| 411 | return $this->getErrorStatus( 'openssl_pkey_get_details' ); |
| 412 | } |
| 413 | |
| 414 | $verifyKey = $result['key']; |
| 415 | } |
| 416 | |
| 417 | if ( $verifyKey !== '' ) { |
| 418 | $this->clearErrors(); |
| 419 | $result = openssl_pkey_get_public( $verifyKey ); |
| 420 | if ( $result === false ) { |
| 421 | return $this->getErrorStatus( 'openssl_pkey_get_public' ); |
| 422 | } |
| 423 | |
| 424 | $this->verifyKey = $result; |
| 425 | } |
| 426 | } |
| 427 | |
| 428 | return Status::newGood(); |
| 429 | } |
| 430 | |
| 431 | /** |
| 432 | * Clears the openssl error string queue. |
| 433 | * Some successful openssl operations still append to this queue, so it must be |
| 434 | * cleared before running operations which may fail and which we want failure details for. |
| 435 | * |
| 436 | * @return void |
| 437 | */ |
| 438 | private function clearErrors(): void { |
| 439 | while ( true ) { |
| 440 | $error = openssl_error_string(); |
| 441 | if ( !$error ) { |
| 442 | break; |
| 443 | } |
| 444 | } |
| 445 | } |
| 446 | |
| 447 | /** |
| 448 | * Encode data using base64 url-safe variant |
| 449 | * |
| 450 | * @param array|string $data |
| 451 | * @return string |
| 452 | */ |
| 453 | private function jwtEncode( $data ): string { |
| 454 | if ( is_array( $data ) ) { |
| 455 | $data = json_encode( $data, JSON_THROW_ON_ERROR | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE ); |
| 456 | } |
| 457 | |
| 458 | return rtrim( strtr( base64_encode( $data ), '+/', '-_' ), '=' ); |
| 459 | } |
| 460 | |
| 461 | /** |
| 462 | * Decode data using base64 url-safe variant |
| 463 | * |
| 464 | * @param string $data |
| 465 | * @param bool $parseJson If true, parse result as JSON |
| 466 | * @return array|string Array if $parseJson is true, string otherwise |
| 467 | */ |
| 468 | private function jwtDecode( string $data, $parseJson = true ) { |
| 469 | $data = base64_decode( strtr( $data, '-_', '+/' ) ); |
| 470 | |
| 471 | if ( $parseJson ) { |
| 472 | return json_decode( $data, true, 4, JSON_THROW_ON_ERROR ); |
| 473 | } else { |
| 474 | return $data; |
| 475 | } |
| 476 | } |
| 477 | |
| 478 | public function cleanup() { |
| 479 | $this->encryptKey = null; |
| 480 | $this->signKey = null; |
| 481 | $this->decryptKey = null; |
| 482 | $this->verifyKey = null; |
| 483 | $this->clearErrors(); |
| 484 | } |
| 485 | |
| 486 | public function canDecrypt() { |
| 487 | $decryptKey = strval( $this->election->getProperty( 'openssl-decrypt-key' ) ); |
| 488 | |
| 489 | return $decryptKey !== ''; |
| 490 | } |
| 491 | |
| 492 | /** |
| 493 | * Return descriptors for any properties this type requires for poll |
| 494 | * creation, for the election, questions, and options. |
| 495 | * |
| 496 | * The returned array should have three keys, "election", "question", and |
| 497 | * "option", each mapping to an array of HTMLForm descriptors. |
| 498 | * |
| 499 | * The descriptors should have an additional key, "SecurePoll_type", with |
| 500 | * the value being "property" or "message". |
| 501 | * |
| 502 | * @return array |
| 503 | */ |
| 504 | public static function getCreateDescriptors() { |
| 505 | global $wgSecurePollOpenSslSignKey; |
| 506 | |
| 507 | $ret = parent::getCreateDescriptors(); |
| 508 | |
| 509 | $ret['election'] += [ |
| 510 | 'openssl-encrypt-key' => [ |
| 511 | 'label-message' => 'securepoll-create-label-openssl_encrypt_key', |
| 512 | 'type' => 'textarea', |
| 513 | 'SecurePoll_type' => 'property', |
| 514 | 'rows' => 5, |
| 515 | 'validation-callback' => static function ( string $key ) { |
| 516 | return self::checkPublicKey( $key ); |
| 517 | }, |
| 518 | ] |
| 519 | ]; |
| 520 | |
| 521 | if ( $wgSecurePollOpenSslSignKey ) { |
| 522 | $ret['election'] += [ |
| 523 | 'openssl-sign-key' => [ |
| 524 | 'type' => 'api', |
| 525 | 'default' => $wgSecurePollOpenSslSignKey, |
| 526 | 'SecurePoll_type' => 'property', |
| 527 | ] |
| 528 | ]; |
| 529 | } else { |
| 530 | $ret['election'] += [ |
| 531 | 'openssl-sign-key' => [ |
| 532 | 'label-message' => 'securepoll-create-label-openssl_sign_key', |
| 533 | 'type' => 'textarea', |
| 534 | 'SecurePoll_type' => 'property', |
| 535 | 'rows' => 5, |
| 536 | 'validation-callback' => static function ( string $key ) { |
| 537 | return self::checkPrivateKey( $key ); |
| 538 | }, |
| 539 | ] |
| 540 | ]; |
| 541 | } |
| 542 | |
| 543 | return $ret; |
| 544 | } |
| 545 | |
| 546 | public function getTallyDescriptors(): array { |
| 547 | $verifyKeyRequired = strval( $this->election->getProperty( 'openssl-sign-key' ) ) === ''; |
| 548 | |
| 549 | return [ |
| 550 | 'openssl-decrypt-key' => [ |
| 551 | 'label-message' => 'securepoll-tally-openssl-decrypt-key', |
| 552 | 'type' => 'textarea', |
| 553 | 'required' => true, |
| 554 | 'rows' => 5, |
| 555 | 'validation-callback' => static function ( string $key ) { |
| 556 | return self::checkPrivateKey( $key ); |
| 557 | }, |
| 558 | ], |
| 559 | 'openssl-verify-key' => [ |
| 560 | 'label-message' => 'securepoll-tally-openssl-verify-key', |
| 561 | 'type' => 'textarea', |
| 562 | 'required' => $verifyKeyRequired, |
| 563 | 'rows' => 5, |
| 564 | 'validation-callback' => static function ( string $key ) use ( $verifyKeyRequired ) { |
| 565 | return self::checkPublicKey( $key, $verifyKeyRequired ); |
| 566 | }, |
| 567 | ], |
| 568 | ]; |
| 569 | } |
| 570 | |
| 571 | /** |
| 572 | * Check validity of an encryption key |
| 573 | * |
| 574 | * @param string $key |
| 575 | * @param bool $required If the key is required to be provided |
| 576 | * @return Message|true |
| 577 | */ |
| 578 | private static function checkPublicKey( string $key, bool $required = true ) { |
| 579 | if ( $key === '' ) { |
| 580 | if ( $required ) { |
| 581 | return Status::newFatal( 'htmlform-required' )->getMessage(); |
| 582 | } else { |
| 583 | // not required so we're fine with this being empty |
| 584 | return true; |
| 585 | } |
| 586 | } |
| 587 | |
| 588 | return self::checkKeyInternal( openssl_pkey_get_public( $key ) ); |
| 589 | } |
| 590 | |
| 591 | /** |
| 592 | * Check validity of a decryption or signing key |
| 593 | * @param string $key |
| 594 | * @return Message|true |
| 595 | */ |
| 596 | public static function checkPrivateKey( string $key ) { |
| 597 | if ( $key === '' ) { |
| 598 | return Status::newFatal( 'htmlform-required' )->getMessage(); |
| 599 | } |
| 600 | |
| 601 | return self::checkKeyInternal( openssl_pkey_get_private( $key ) ); |
| 602 | } |
| 603 | |
| 604 | /** |
| 605 | * Internal validation routine for public or private keys |
| 606 | * |
| 607 | * @param OpenSSLAsymmetricKey|resource|false $key |
| 608 | * @return Message|true |
| 609 | */ |
| 610 | private static function checkKeyInternal( $key ) { |
| 611 | if ( $key === false ) { |
| 612 | return Status::newFatal( 'securepoll-openssl-invalid-key' )->getMessage(); |
| 613 | } |
| 614 | |
| 615 | $result = openssl_pkey_get_details( $key ); |
| 616 | if ( $result === false || $result['type'] !== OPENSSL_KEYTYPE_RSA || $result['bits'] < 2048 ) { |
| 617 | return Status::newFatal( 'securepoll-openssl-invalid-key' )->getMessage(); |
| 618 | } |
| 619 | |
| 620 | return true; |
| 621 | } |
| 622 | |
| 623 | public function updateTallyContext( Context $context, array $data ): void { |
| 624 | // no-op |
| 625 | } |
| 626 | |
| 627 | public function updateDbForTallyJob( int $electionId, IDatabase $dbw, array $data ): void { |
| 628 | // Add private key to DB if it was entered in the form |
| 629 | if ( isset( $data['openssl-decrypt-key'] ) ) { |
| 630 | $dbw->newReplaceQueryBuilder() |
| 631 | ->replaceInto( 'securepoll_properties' ) |
| 632 | ->uniqueIndexFields( [ 'pr_entity', 'pr_key' ] ) |
| 633 | ->row( [ |
| 634 | 'pr_entity' => $electionId, |
| 635 | 'pr_key' => 'openssl-decrypt-key', |
| 636 | 'pr_value' => $data['openssl-decrypt-key'] |
| 637 | ] ) |
| 638 | ->caller( __METHOD__ )->execute(); |
| 639 | } |
| 640 | } |
| 641 | |
| 642 | public function cleanupDbForTallyJob( int $electionId, IDatabase $dbw ): void { |
| 643 | $dbw->newDeleteQueryBuilder() |
| 644 | ->deleteFrom( 'securepoll_properties' ) |
| 645 | ->where( [ |
| 646 | 'pr_entity' => $electionId, |
| 647 | 'pr_key' => 'openssl-decrypt-key', |
| 648 | ] ) |
| 649 | ->caller( __METHOD__ )->execute(); |
| 650 | } |
| 651 | |
| 652 | /** |
| 653 | * Retrieve the URL of Special:SecurePoll, for validating JWTs. |
| 654 | * |
| 655 | * @return string |
| 656 | */ |
| 657 | private static function getIssuer(): string { |
| 658 | return SpecialPage::getTitleFor( 'SecurePoll' )->getCanonicalURL(); |
| 659 | } |
| 660 | } |