Total Complexity | 62 |
Total Lines | 495 |
Duplicated Lines | 0 % |
Changes | 1 | ||
Bugs | 0 | Features | 0 |
Complex classes like Webauthn often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Webauthn, and based on these observations, apply Extract Interface, too.
1 | <?php |
||
58 | class Webauthn |
||
59 | { |
||
60 | /** |
||
61 | * The attestation data formats |
||
62 | * @var array<string> |
||
63 | */ |
||
64 | protected array $formats = []; |
||
65 | |||
66 | /** |
||
67 | * The challenge to use |
||
68 | * @var ByteBuffer|null |
||
69 | */ |
||
70 | protected ?ByteBuffer $challenge = null; |
||
71 | |||
72 | /** |
||
73 | * The signature counter |
||
74 | * @var int |
||
75 | */ |
||
76 | protected int $signatureCounter = 0; |
||
77 | |||
78 | /** |
||
79 | * The relying party entity |
||
80 | * @var RelyingParty |
||
81 | */ |
||
82 | protected RelyingParty $relyingParty; |
||
83 | |||
84 | /** |
||
85 | * The certificates files path |
||
86 | * @var array<string> |
||
87 | */ |
||
88 | protected array $certificates = []; |
||
89 | |||
90 | /** |
||
91 | * The configuration instance |
||
92 | * @var WebauthnConfiguration |
||
93 | */ |
||
94 | protected WebauthnConfiguration $config; |
||
95 | |||
96 | /** |
||
97 | * Create new instance |
||
98 | * @param WebauthnConfiguration $config |
||
99 | * @param array<string> $allowedFormats |
||
100 | */ |
||
101 | public function __construct(WebauthnConfiguration $config, array $allowedFormats = []) |
||
102 | { |
||
103 | if (! function_exists('openssl_open')) { |
||
104 | throw new WebauthnException('OpenSSL module not installed in this platform'); |
||
105 | } |
||
106 | |||
107 | if (! in_array('SHA256', array_map('strtoupper', openssl_get_md_methods()))) { |
||
108 | throw new WebauthnException('SHA256 is not supported by this OpenSSL installation'); |
||
109 | } |
||
110 | |||
111 | $this->config = $config; |
||
112 | $this->formats = $this->normalizeFormats($allowedFormats); |
||
113 | |||
114 | $this->relyingParty = new RelyingParty( |
||
115 | $config->get('relying_party_id'), |
||
|
|||
116 | $config->get('relying_party_name'), |
||
117 | $config->get('relying_party_logo') |
||
118 | ); |
||
119 | } |
||
120 | |||
121 | /** |
||
122 | * Add a root certificate to verify new registrations |
||
123 | * @param string $path |
||
124 | * @return $this |
||
125 | */ |
||
126 | public function addRootCertificate(string $path): self |
||
131 | } |
||
132 | |||
133 | /** |
||
134 | * Return the parameters to be used for the registration |
||
135 | * @param string $userId |
||
136 | * @param string $userName |
||
137 | * @param string $userDisplayName |
||
138 | * @param string $userVerificationType |
||
139 | * @param bool $crossPlatformAttachment |
||
140 | * @param array<string> $excludeCredentialIds |
||
141 | * @param bool $withoutAttestation |
||
142 | * @return PublicKey |
||
143 | */ |
||
144 | public function getRegistrationParams( |
||
145 | string $userId, |
||
146 | string $userName, |
||
147 | string $userDisplayName, |
||
148 | string $userVerificationType, |
||
149 | bool $crossPlatformAttachment = false, |
||
150 | array $excludeCredentialIds = [], |
||
151 | bool $withoutAttestation = false |
||
152 | ): PublicKey { |
||
153 | $excludeCredentials = []; |
||
154 | foreach ($excludeCredentialIds as $id) { |
||
155 | $hex = hex2bin($id); |
||
156 | if ($hex === false) { |
||
157 | throw new WebauthnException(sprintf('Can not convert credential id [%s] to binary', $id)); |
||
158 | } |
||
159 | |||
160 | $excludeCredentials[] = new UserCredential( |
||
161 | new ByteBuffer($hex), |
||
162 | array_values(TransportType::all()) |
||
163 | ); |
||
164 | } |
||
165 | |||
166 | $attestation = AttestationType::INDIRECT; |
||
167 | if (count($this->certificates) > 0) { |
||
168 | $attestation = AttestationType::DIRECT; |
||
169 | } |
||
170 | |||
171 | if ($withoutAttestation) { |
||
172 | $attestation = AttestationType::NONE; |
||
173 | } |
||
174 | |||
175 | $relyingParty = new RelyingParty( |
||
176 | $this->config->get('relying_party_id'), |
||
177 | $this->config->get('relying_party_name'), |
||
178 | $this->config->get('relying_party_logo') |
||
179 | ); |
||
180 | |||
181 | $userInfo = new UserInfo( |
||
182 | new ByteBuffer($userId), |
||
183 | $userName, |
||
184 | $userDisplayName |
||
185 | ); |
||
186 | |||
187 | $authenticatorSelection = new AuthenticatorSelection( |
||
188 | $userVerificationType, |
||
189 | false, |
||
190 | $crossPlatformAttachment |
||
191 | ); |
||
192 | |||
193 | $publicKey = (new PublicKey()) |
||
194 | ->setUserInfo($userInfo) |
||
195 | ->setRelyingParty($relyingParty) |
||
196 | ->setAuthenticatorSelection($authenticatorSelection) |
||
197 | ->setExcludeCredentials($excludeCredentials) |
||
198 | ->setChallenge($this->createChallenge()) |
||
199 | ->setTimeout($this->config->get('timeout')) |
||
200 | ->setExtensions() |
||
201 | ->addPublicKeys() |
||
202 | ->setAttestation($attestation); |
||
203 | |||
204 | return $publicKey; |
||
205 | } |
||
206 | |||
207 | /** |
||
208 | * Return the authentication parameters |
||
209 | * @param string $userVerificationType |
||
210 | * @param array<string> $credentialIds |
||
211 | * @return PublicKey |
||
212 | */ |
||
213 | public function getAuthenticationParams( |
||
214 | string $userVerificationType, |
||
215 | array $credentialIds = [] |
||
216 | ): PublicKey { |
||
217 | $allowedCredentials = []; |
||
218 | foreach ($credentialIds as $id) { |
||
219 | $hex = hex2bin($id); |
||
220 | if ($hex === false) { |
||
221 | throw new WebauthnException(sprintf('Can not convert credential id [%s] to binary', $id)); |
||
222 | } |
||
223 | |||
224 | $allowedCredentials[] = new PublicKeyAuthParam( |
||
225 | new ByteBuffer($hex), |
||
226 | $this->config->get('transport_types') |
||
227 | ); |
||
228 | } |
||
229 | |||
230 | $publicKey = (new PublicKey()) |
||
231 | ->setRelyingPartyId($this->relyingParty->getId()) |
||
232 | ->setAllowCredentials($allowedCredentials) |
||
233 | ->setChallenge($this->createChallenge()) |
||
234 | ->setTimeout($this->config->get('timeout')) |
||
235 | ->setUserVerificationType($userVerificationType); |
||
236 | |||
237 | return $publicKey; |
||
238 | } |
||
239 | |||
240 | /** |
||
241 | * Process the user registration |
||
242 | * @param string $clientDataJson |
||
243 | * @param string $attestationObject |
||
244 | * @param string|ByteBuffer $challenge |
||
245 | * @param bool $requireUserVerification |
||
246 | * @param bool $requireUserPresent |
||
247 | * @param bool $failIfRootCertificateMismatch |
||
248 | * @return array<string, mixed> |
||
249 | */ |
||
250 | public function processRegistration( |
||
251 | string $clientDataJson, |
||
252 | string $attestationObject, |
||
253 | $challenge, |
||
254 | bool $requireUserVerification = false, |
||
255 | bool $requireUserPresent = true, |
||
256 | bool $failIfRootCertificateMismatch = true |
||
257 | ): array { |
||
258 | $clientDataHash = hash('sha256', $clientDataJson, true); |
||
259 | if (is_string($challenge)) { |
||
260 | $challenge = new ByteBuffer($challenge); |
||
261 | } |
||
262 | |||
263 | // security: https://www.w3.org/TR/webauthn/#registering-a-new-credential |
||
264 | try { |
||
265 | // 2. Let C, the client data claimed as collected during the credential creation, |
||
266 | // be the result of running an implementation-specific JSON parser on JSONtext. |
||
267 | $clientData = Json::decode($clientDataJson); |
||
268 | } catch (Exception $ex) { |
||
269 | throw new WebauthnException(sprintf('Invalid client data provided, [%s]', $ex->getMessage())); |
||
270 | } |
||
271 | |||
272 | // 3. Verify that the value of C.type is webauthn.create. |
||
273 | if (! isset($clientData->type) || $clientData->type !== 'webauthn.create') { |
||
274 | throw new WebauthnException('Invalid client type provided'); |
||
275 | } |
||
276 | |||
277 | // 4. Verify that the value of C.challenge matches the challenge that was |
||
278 | // sent to the authenticator in the create() call. |
||
279 | if ( |
||
280 | ! isset($clientData->challenge) || |
||
281 | ByteBuffer::fromBase64Url($clientData->challenge)->getBinaryString() !== $challenge->getBinaryString() |
||
282 | ) { |
||
283 | throw new WebauthnException('Invalid challenge provided'); |
||
284 | } |
||
285 | |||
286 | // 5. Verify that the value of C.origin matches the Relying Party's origin. |
||
287 | if (! isset($clientData->origin) || $this->checkOrigin($clientData->origin) === false) { |
||
288 | throw new WebauthnException('Invalid origin provided'); |
||
289 | } |
||
290 | |||
291 | $attestation = new AttestationData($attestationObject, $this->formats); |
||
292 | |||
293 | // 9. Verify that the RP ID hash in authData is indeed the SHA-256 |
||
294 | // hash of the RP ID expected by the RP. |
||
295 | if ($attestation->validateRelyingPartyIdHash($this->relyingParty->getHashId()) === false) { |
||
296 | throw new WebauthnException('Invalid relying party id hash provided'); |
||
297 | } |
||
298 | |||
299 | // 14. Verify that attStmt is a correct attestation statement, conveying |
||
300 | // a valid attestation signature |
||
301 | if ($attestation->validateAttestation($clientDataHash) === false) { |
||
302 | throw new WebauthnException('Invalid certificate signature'); |
||
303 | } |
||
304 | |||
305 | // 15. If validation is successful, obtain a list of acceptable trust anchors |
||
306 | $isRootValid = count($this->certificates) > 0 |
||
307 | ? $attestation->validateRootCertificate($this->certificates) |
||
308 | : false; |
||
309 | |||
310 | if ($failIfRootCertificateMismatch && count($this->certificates) > 0 && $isRootValid === false) { |
||
311 | throw new WebauthnException('Invalid root certificate'); |
||
312 | } |
||
313 | |||
314 | // 10. Verify that the User Present bit of the flags in authData is set. |
||
315 | $userPresent = $attestation->getAuthenticatorData()->isUserPresent(); |
||
316 | if ($requireUserPresent && $userPresent === false) { |
||
317 | throw new WebauthnException('User is not present during authentication'); |
||
318 | } |
||
319 | |||
320 | // 11. If user verification is required for this registration, verify |
||
321 | // that the User Verified bit of the flags in authData is set. |
||
322 | $userVerified = $attestation->getAuthenticatorData()->isUserVerified(); |
||
323 | if ($requireUserVerification && $userVerified === false) { |
||
324 | throw new WebauthnException('User is not verified during authentication'); |
||
325 | } |
||
326 | |||
327 | $signCount = $attestation->getAuthenticatorData()->getSignatureCount(); |
||
328 | if ($signCount > 0) { |
||
329 | $this->signatureCounter = $signCount; |
||
330 | } |
||
331 | |||
332 | // prepare data to store for future logins |
||
333 | $data = [ |
||
334 | 'rp_id' => $this->relyingParty->getId(), |
||
335 | 'attestation_format' => $attestation->getFormatName(), |
||
336 | 'credential_id' => bin2hex($attestation->getAuthenticatorData()->getCredentialId()), |
||
337 | 'credential_public_key' => $attestation->getAuthenticatorData()->getPublicKeyPEM(), |
||
338 | 'certificate_chain' => $attestation->getCertificateChain(), |
||
339 | 'certificate' => $attestation->getCertificatePem(), |
||
340 | 'certificate_issuer' => $attestation->getCertificateIssuer(), |
||
341 | 'certificate_subject' => $attestation->getCertificateSubject(), |
||
342 | 'root_certificate_valid' => $isRootValid, |
||
343 | 'signature_counter' => $this->signatureCounter, |
||
344 | 'aaguid' => bin2hex($attestation->getAuthenticatorData()->getAaguid()), |
||
345 | 'user_present' => $userPresent, |
||
346 | 'user_verified' => $userVerified, |
||
347 | ]; |
||
348 | |||
349 | |||
350 | return $data; |
||
351 | } |
||
352 | |||
353 | /** |
||
354 | * Process the user authentication |
||
355 | * @param string $clientDataJson |
||
356 | * @param string $authenticatorData |
||
357 | * @param string $signature |
||
358 | * @param string $credentialPublicKey |
||
359 | * @param ByteBuffer|string $challenge |
||
360 | * @param int|null $previousSignatureCount |
||
361 | * @param bool $requireUserVerification |
||
362 | * @param bool $requireUserPresent |
||
363 | * @return bool |
||
364 | */ |
||
365 | public function processAuthentication( |
||
366 | string $clientDataJson, |
||
367 | string $authenticatorData, |
||
368 | string $signature, |
||
369 | string $credentialPublicKey, |
||
370 | $challenge, |
||
371 | ?int $previousSignatureCount = null, |
||
372 | bool $requireUserVerification = false, |
||
373 | bool $requireUserPresent = true |
||
374 | ): bool { |
||
375 | if (is_string($challenge)) { |
||
376 | $challenge = new ByteBuffer($challenge); |
||
377 | } |
||
378 | $clientDataHash = hash('sha256', $clientDataJson, true); |
||
379 | $authenticator = new AuthenticatorData($authenticatorData); |
||
380 | try { |
||
381 | // 5. Let JSON text be the result of running UTF-8 decode on the value of cData. |
||
382 | $clientData = Json::decode($clientDataJson); |
||
383 | } catch (Exception $ex) { |
||
384 | throw new WebauthnException(sprintf('Invalid client data provided, [%s]', $ex->getMessage())); |
||
385 | } |
||
386 | |||
387 | // https://www.w3.org/TR/webauthn/#verifying-assertion |
||
388 | |||
389 | // 1. If the allowCredentials option was given when this authentication ceremony was initiated, |
||
390 | // verify that credential.id identifies one of the public key credentials |
||
391 | // that were listed in allowCredentials. |
||
392 | // -> TO BE VERIFIED BY IMPLEMENTATION |
||
393 | |||
394 | // 2. If credential.response.userHandle is present, verify that the user identified |
||
395 | // by this value is the owner of the public key credential identified by credential.id. |
||
396 | // -> TO BE VERIFIED BY IMPLEMENTATION |
||
397 | |||
398 | // 3. Using credential’s id attribute (or the corresponding rawId, if base64url encoding is |
||
399 | // inappropriate for your use case), |
||
400 | // look up the corresponding credential public key. |
||
401 | // -> TO BE LOOKED UP BY IMPLEMENTATION |
||
402 | |||
403 | // 7. Verify that the value of C.type is the string webauthn.get. |
||
404 | if (! isset($clientData->type) || $clientData->type !== 'webauthn.get') { |
||
405 | throw new WebauthnException('Invalid client type provided'); |
||
406 | } |
||
407 | |||
408 | // 8. Verify that the value of C.challenge matches the challenge that was sent to the |
||
409 | // authenticator in the PublicKeyCredentialRequestOptions passed to the get() call. |
||
410 | if ( |
||
411 | ! isset($clientData->challenge) || |
||
412 | ByteBuffer::fromBase64Url($clientData->challenge)->getBinaryString() !== $challenge->getBinaryString() |
||
413 | ) { |
||
414 | throw new WebauthnException('Invalid challenge provided'); |
||
415 | } |
||
416 | |||
417 | // 9. Verify that the value of C.origin matches the Relying Party's origin. |
||
418 | if (! isset($clientData->origin) || $this->checkOrigin($clientData->origin) === false) { |
||
419 | throw new WebauthnException('Invalid origin provided'); |
||
420 | } |
||
421 | |||
422 | // 11. Verify that the rpIdHash in authData is the SHA-256 hash |
||
423 | // of the RP ID expected by the Relying Party. |
||
424 | if ($authenticator->getRelyingPartyIdHash() !== $this->relyingParty->getHashId()) { |
||
425 | throw new WebauthnException('Invalid relying party id hash provided'); |
||
426 | } |
||
427 | |||
428 | // 12. Verify that the User Present bit of the flags in authData is set |
||
429 | if ($requireUserPresent && $authenticator->isUserPresent() === false) { |
||
430 | throw new WebauthnException('User is not present during authentication'); |
||
431 | } |
||
432 | |||
433 | // 13. If user verification is required for this assertion, verify that |
||
434 | // the User Verified bit of the flags in authData is set. |
||
435 | if ($requireUserVerification && $authenticator->isUserVerified() === false) { |
||
436 | throw new WebauthnException('User is not verified during authentication'); |
||
437 | } |
||
438 | |||
439 | // 14. Verify the values of the client extension outputs |
||
440 | // TODO (extensions not implemented) |
||
441 | |||
442 | // 16. Using the credential public key looked up in step 3, verify |
||
443 | // that sig is a valid signature over the binary |
||
444 | // concatenation of authData and hash. |
||
445 | $dataToVerify = ''; |
||
446 | $dataToVerify .= $authenticatorData; |
||
447 | $dataToVerify .= $clientDataHash; |
||
448 | |||
449 | $publicKey = openssl_pkey_get_public($credentialPublicKey); |
||
450 | if ($publicKey === false) { |
||
451 | throw new WebauthnException('Invalid public key provided'); |
||
452 | } |
||
453 | |||
454 | if ( |
||
455 | openssl_verify( |
||
456 | $dataToVerify, |
||
457 | $signature, |
||
458 | $publicKey, |
||
459 | OPENSSL_ALGO_SHA256 |
||
460 | ) !== 1 |
||
461 | ) { |
||
462 | throw new WebauthnException('Invalid signature provided'); |
||
463 | } |
||
464 | |||
465 | $signatureCount = $authenticator->getSignatureCount(); |
||
466 | if ($signatureCount !== 0) { |
||
467 | $this->signatureCounter = $signatureCount; |
||
468 | } |
||
469 | |||
470 | // 17. If either of the signature counter value authData.signCount or |
||
471 | // previous signature count is non-zero, and if authData.signCount |
||
472 | // less than or equal to previous signature count, it's a signal |
||
473 | // that the authenticator may be cloned |
||
474 | if ($previousSignatureCount !== null) { |
||
475 | if ($signatureCount !== 0 || $previousSignatureCount !== 0) { |
||
476 | if ($previousSignatureCount >= $signatureCount) { |
||
477 | throw new WebauthnException('Invalid signature counter provided'); |
||
478 | } |
||
479 | } |
||
480 | } |
||
481 | |||
482 | return true; |
||
483 | } |
||
484 | |||
485 | /** |
||
486 | * Return the challenge |
||
487 | * @return ByteBuffer|null |
||
488 | */ |
||
489 | public function getChallenge(): ?ByteBuffer |
||
490 | { |
||
491 | return $this->challenge; |
||
492 | } |
||
493 | |||
494 | |||
495 | /** |
||
496 | * Check the given origin |
||
497 | * @param string $origin |
||
498 | * @return bool |
||
499 | */ |
||
500 | protected function checkOrigin(string $origin): bool |
||
516 | } |
||
517 | |||
518 | /** |
||
519 | * Create the challenge if not yet created |
||
520 | * @return ByteBuffer |
||
521 | */ |
||
522 | protected function createChallenge(): ByteBuffer |
||
523 | { |
||
524 | if ($this->challenge === null) { |
||
525 | $length = $this->config->get('challenge_length'); |
||
526 | $this->challenge = ByteBuffer::randomBuffer($length); |
||
527 | } |
||
528 | |||
529 | return $this->challenge; |
||
530 | } |
||
531 | |||
532 | /** |
||
533 | * Normalize the formats |
||
534 | * @param array<string> $formats |
||
535 | * @return array<string> |
||
536 | */ |
||
537 | protected function normalizeFormats(array $formats): array |
||
553 | } |
||
554 | } |
||
555 |