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<?php
declare(strict_types=1);
/**
* SPDX-FileCopyrightText: 2020 Nextcloud GmbH and Nextcloud contributors
* SPDX-License-Identifier: AGPL-3.0-or-later
*/
namespace OC\Authentication\WebAuthn;
use Cose\Algorithm\Signature\ECDSA\ES256;
use Cose\Algorithm\Signature\RSA\RS256;
use Cose\Algorithms;
use GuzzleHttp\Psr7\ServerRequest;
use OC\Authentication\WebAuthn\Db\PublicKeyCredentialEntity;
use OC\Authentication\WebAuthn\Db\PublicKeyCredentialMapper;
use OCP\AppFramework\Db\DoesNotExistException;
use OCP\IConfig;
use OCP\IUser;
use Psr\Log\LoggerInterface;
use Webauthn\AttestationStatement\AttestationObjectLoader;
use Webauthn\AttestationStatement\AttestationStatementSupportManager;
use Webauthn\AttestationStatement\NoneAttestationStatementSupport;
use Webauthn\AuthenticationExtensions\ExtensionOutputCheckerHandler;
use Webauthn\AuthenticatorAssertionResponse;
use Webauthn\AuthenticatorAssertionResponseValidator;
use Webauthn\AuthenticatorAttestationResponse;
use Webauthn\AuthenticatorAttestationResponseValidator;
use Webauthn\AuthenticatorSelectionCriteria;
use Webauthn\PublicKeyCredentialCreationOptions;
use Webauthn\PublicKeyCredentialDescriptor;
use Webauthn\PublicKeyCredentialLoader;
use Webauthn\PublicKeyCredentialParameters;
use Webauthn\PublicKeyCredentialRequestOptions;
use Webauthn\PublicKeyCredentialRpEntity;
use Webauthn\PublicKeyCredentialUserEntity;
use Webauthn\TokenBinding\TokenBindingNotSupportedHandler;
class Manager {
/** @var CredentialRepository */
private $repository;
/** @var PublicKeyCredentialMapper */
private $credentialMapper;
/** @var LoggerInterface */
private $logger;
/** @var IConfig */
private $config;
public function __construct(
CredentialRepository $repository,
PublicKeyCredentialMapper $credentialMapper,
LoggerInterface $logger,
IConfig $config,
) {
$this->repository = $repository;
$this->credentialMapper = $credentialMapper;
$this->logger = $logger;
$this->config = $config;
}
public function startRegistration(IUser $user, string $serverHost): PublicKeyCredentialCreationOptions {
$rpEntity = new PublicKeyCredentialRpEntity(
'Nextcloud', //Name
$this->stripPort($serverHost), //ID
null //Icon
);
$userEntity = new PublicKeyCredentialUserEntity(
$user->getUID(), // Name
$user->getUID(), // ID
$user->getDisplayName() // Display name
// 'https://foo.example.co/avatar/123e4567-e89b-12d3-a456-426655440000' //Icon
);
$challenge = random_bytes(32);
$publicKeyCredentialParametersList = [
new PublicKeyCredentialParameters('public-key', Algorithms::COSE_ALGORITHM_ES256),
new PublicKeyCredentialParameters('public-key', Algorithms::COSE_ALGORITHM_RS256),
];
$timeout = 60000;
$excludedPublicKeyDescriptors = [
];
$authenticatorSelectionCriteria = new AuthenticatorSelectionCriteria(
AuthenticatorSelectionCriteria::AUTHENTICATOR_ATTACHMENT_NO_PREFERENCE,
AuthenticatorSelectionCriteria::USER_VERIFICATION_REQUIREMENT_PREFERRED,
null,
false,
);
return new PublicKeyCredentialCreationOptions(
$rpEntity,
$userEntity,
$challenge,
$publicKeyCredentialParametersList,
$authenticatorSelectionCriteria,
PublicKeyCredentialCreationOptions::ATTESTATION_CONVEYANCE_PREFERENCE_NONE,
$excludedPublicKeyDescriptors,
$timeout,
);
}
public function finishRegister(PublicKeyCredentialCreationOptions $publicKeyCredentialCreationOptions, string $name, string $data): PublicKeyCredentialEntity {
$tokenBindingHandler = new TokenBindingNotSupportedHandler();
$attestationStatementSupportManager = new AttestationStatementSupportManager();
$attestationStatementSupportManager->add(new NoneAttestationStatementSupport());
$attestationObjectLoader = new AttestationObjectLoader($attestationStatementSupportManager);
$publicKeyCredentialLoader = new PublicKeyCredentialLoader($attestationObjectLoader);
// Extension Output Checker Handler
$extensionOutputCheckerHandler = new ExtensionOutputCheckerHandler();
// Authenticator Attestation Response Validator
$authenticatorAttestationResponseValidator = new AuthenticatorAttestationResponseValidator(
$attestationStatementSupportManager,
$this->repository,
$tokenBindingHandler,
$extensionOutputCheckerHandler
);
$authenticatorAttestationResponseValidator->setLogger($this->logger);
try {
// Load the data
$publicKeyCredential = $publicKeyCredentialLoader->load($data);
$response = $publicKeyCredential->response;
// Check if the response is an Authenticator Attestation Response
if (!$response instanceof AuthenticatorAttestationResponse) {
throw new \RuntimeException('Not an authenticator attestation response');
}
// Check the response against the request
$request = ServerRequest::fromGlobals();
$publicKeyCredentialSource = $authenticatorAttestationResponseValidator->check(
$response,
$publicKeyCredentialCreationOptions,
$request,
['localhost'],
);
} catch (\Throwable $exception) {
throw $exception;
}
// Persist the data
$userVerification = $response->attestationObject->authData->isUserVerified();
return $this->repository->saveAndReturnCredentialSource($publicKeyCredentialSource, $name, $userVerification);
}
private function stripPort(string $serverHost): string {
return preg_replace('/(:\d+$)/', '', $serverHost);
}
public function startAuthentication(string $uid, string $serverHost): PublicKeyCredentialRequestOptions {
// List of registered PublicKeyCredentialDescriptor classes associated to the user
$userVerificationRequirement = AuthenticatorSelectionCriteria::USER_VERIFICATION_REQUIREMENT_REQUIRED;
$registeredPublicKeyCredentialDescriptors = array_map(function (PublicKeyCredentialEntity $entity) use (&$userVerificationRequirement) {
if ($entity->getUserVerification() !== true) {
$userVerificationRequirement = AuthenticatorSelectionCriteria::USER_VERIFICATION_REQUIREMENT_DISCOURAGED;
}
$credential = $entity->toPublicKeyCredentialSource();
return new PublicKeyCredentialDescriptor(
$credential->type,
$credential->publicKeyCredentialId,
);
}, $this->credentialMapper->findAllForUid($uid));
// Public Key Credential Request Options
return new PublicKeyCredentialRequestOptions(
random_bytes(32), // Challenge
$this->stripPort($serverHost), // Relying Party ID
$registeredPublicKeyCredentialDescriptors, // Registered PublicKeyCredentialDescriptor classes
$userVerificationRequirement,
60000, // Timeout
);
}
public function finishAuthentication(PublicKeyCredentialRequestOptions $publicKeyCredentialRequestOptions, string $data, string $uid) {
$attestationStatementSupportManager = new AttestationStatementSupportManager();
$attestationStatementSupportManager->add(new NoneAttestationStatementSupport());
$attestationObjectLoader = new AttestationObjectLoader($attestationStatementSupportManager);
$publicKeyCredentialLoader = new PublicKeyCredentialLoader($attestationObjectLoader);
$tokenBindingHandler = new TokenBindingNotSupportedHandler();
$extensionOutputCheckerHandler = new ExtensionOutputCheckerHandler();
$algorithmManager = new \Cose\Algorithm\Manager();
$algorithmManager->add(new ES256());
$algorithmManager->add(new RS256());
$authenticatorAssertionResponseValidator = new AuthenticatorAssertionResponseValidator(
$this->repository,
$tokenBindingHandler,
$extensionOutputCheckerHandler,
$algorithmManager,
);
$authenticatorAssertionResponseValidator->setLogger($this->logger);
try {
$this->logger->debug('Loading publickey credentials from: ' . $data);
// Load the data
$publicKeyCredential = $publicKeyCredentialLoader->load($data);
$response = $publicKeyCredential->response;
// Check if the response is an Authenticator Attestation Response
if (!$response instanceof AuthenticatorAssertionResponse) {
throw new \RuntimeException('Not an authenticator attestation response');
}
// Check the response against the request
$request = ServerRequest::fromGlobals();
$publicKeyCredentialSource = $authenticatorAssertionResponseValidator->check(
$publicKeyCredential->rawId,
$response,
$publicKeyCredentialRequestOptions,
$request,
$uid,
['localhost'],
);
} catch (\Throwable $e) {
throw $e;
}
return true;
}
public function deleteRegistration(IUser $user, int $id): void {
try {
$entry = $this->credentialMapper->findById($user->getUID(), $id);
} catch (DoesNotExistException $e) {
$this->logger->warning("WebAuthn device $id does not exist, can't delete it");
return;
}
$this->credentialMapper->delete($entry);
}
public function isWebAuthnAvailable(): bool {
if (!extension_loaded('bcmath')) {
return false;
}
if (!extension_loaded('gmp')) {
return false;
}
if (!$this->config->getSystemValueBool('auth.webauthn.enabled', true)) {
return false;
}
return true;
}
}
|
