Merge pull request #38773 from nextcloud/fix/noid/protect-oauth2-api-controller

Add bruteforce protection in OauthApiController

Author: julien-nc

apps/oauth2/lib/Controller/OauthApiController.php

@@ -64,6 +64,7 @@ public function __construct(
 	/**
 	 * @PublicPage
 	 * @NoCSRFRequired
+	 * @BruteForceProtection(action=oauth2GetToken)
 	 *
 	 * @param string $grant_type
 	 * @param string $code
@@ -76,9 +77,11 @@ public function getToken($grant_type, $code, $refresh_token, $client_id, $client
 
 		// We only handle two types
 		if ($grant_type !== 'authorization_code' && $grant_type !== 'refresh_token') {
-			return new JSONResponse([
+			$response = new JSONResponse([
 				'error' => 'invalid_grant',
 			], Http::STATUS_BAD_REQUEST);
+			$response->throttle(['invalid_grant' => $grant_type]);
+			return $response;
 		}
 
 		// We handle the initial and refresh tokens the same way
@@ -89,17 +92,21 @@ public function getToken($grant_type, $code, $refresh_token, $client_id, $client
 		try {
 			$accessToken = $this->accessTokenMapper->getByCode($code);
 		} catch (AccessTokenNotFoundException $e) {
-			return new JSONResponse([
+			$response = new JSONResponse([
 				'error' => 'invalid_request',
 			], Http::STATUS_BAD_REQUEST);
+			$response->throttle(['invalid_request' => 'token not found', 'code' => $code]);
+			return $response;
 		}
 
 		try {
 			$client = $this->clientMapper->getByUid($accessToken->getClientId());
 		} catch (ClientNotFoundException $e) {
-			return new JSONResponse([
+			$response = new JSONResponse([
 				'error' => 'invalid_request',
 			], Http::STATUS_BAD_REQUEST);
+			$response->throttle(['invalid_request' => 'client not found', 'client_id' => $accessToken->getClientId()]);
+			return $response;
 		}
 
 		if (isset($this->request->server['PHP_AUTH_USER'])) {
@@ -111,15 +118,18 @@ public function getToken($grant_type, $code, $refresh_token, $client_id, $client
 			$storedClientSecret = $this->crypto->decrypt($client->getSecret());
 		} catch (\Exception $e) {
 			$this->logger->error('OAuth client secret decryption error', ['exception' => $e]);
+			// we don't throttle here because it might not be a bruteforce attack
 			return new JSONResponse([
 				'error' => 'invalid_client',
 			], Http::STATUS_BAD_REQUEST);
 		}
 		// The client id and secret must match. Else we don't provide an access token!
 		if ($client->getClientIdentifier() !== $client_id || $storedClientSecret !== $client_secret) {
-			return new JSONResponse([
+			$response = new JSONResponse([
 				'error' => 'invalid_client',
 			], Http::STATUS_BAD_REQUEST);
+			$response->throttle(['invalid_client' => 'client ID or secret does not match']);
+			return $response;
 		}
 
 		$decryptedToken = $this->crypto->decrypt($accessToken->getEncryptedToken(), $code);
@@ -132,9 +142,11 @@ public function getToken($grant_type, $code, $refresh_token, $client_id, $client
 		} catch (InvalidTokenException $e) {
 			//We can't do anything...
 			$this->accessTokenMapper->delete($accessToken);
-			return new JSONResponse([
+			$response = new JSONResponse([
 				'error' => 'invalid_request',
 			], Http::STATUS_BAD_REQUEST);
+			$response->throttle(['invalid_request' => 'token is invalid']);
+			return $response;
 		}
 
 		// Rotate the apptoken (so the old one becomes invalid basically)

apps/oauth2/tests/Controller/OauthApiControllerTest.php

@@ -104,6 +104,7 @@ public function testGetTokenInvalidGrantType() {
 		$expected = new JSONResponse([
 			'error' => 'invalid_grant',
 		], Http::STATUS_BAD_REQUEST);
+		$expected->throttle(['invalid_grant' => 'foo']);
 
 		$this->assertEquals($expected, $this->oauthApiController->getToken('foo', null, null, null, null));
 	}
@@ -112,6 +113,7 @@ public function testGetTokenInvalidCode() {
 		$expected = new JSONResponse([
 			'error' => 'invalid_request',
 		], Http::STATUS_BAD_REQUEST);
+		$expected->throttle(['invalid_request' => 'token not found', 'code' => 'invalidcode']);
 
 		$this->accessTokenMapper->method('getByCode')
 			->with('invalidcode')
@@ -124,6 +126,7 @@ public function testGetTokenInvalidRefreshToken() {
 		$expected = new JSONResponse([
 			'error' => 'invalid_request',
 		], Http::STATUS_BAD_REQUEST);
+		$expected->throttle(['invalid_request' => 'token not found', 'code' => 'invalidrefresh']);
 
 		$this->accessTokenMapper->method('getByCode')
 			->with('invalidrefresh')
@@ -136,6 +139,7 @@ public function testGetTokenClientDoesNotExist() {
 		$expected = new JSONResponse([
 			'error' => 'invalid_request',
 		], Http::STATUS_BAD_REQUEST);
+		$expected->throttle(['invalid_request' => 'client not found', 'client_id' => 42]);
 
 		$accessToken = new AccessToken();
 		$accessToken->setClientId(42);
@@ -169,6 +173,7 @@ public function testGetTokenInvalidClient($clientId, $clientSecret) {
 		$expected = new JSONResponse([
 			'error' => 'invalid_client',
 		], Http::STATUS_BAD_REQUEST);
+		$expected->throttle(['invalid_client' => 'client ID or secret does not match']);
 
 		$accessToken = new AccessToken();
 		$accessToken->setClientId(42);
@@ -191,6 +196,7 @@ public function testGetTokenInvalidAppToken() {
 		$expected = new JSONResponse([
 			'error' => 'invalid_request',
 		], Http::STATUS_BAD_REQUEST);
+		$expected->throttle(['invalid_request' => 'token is invalid']);
 
 		$accessToken = new AccessToken();
 		$accessToken->setClientId(42);