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| 1 | <?php declare(strict_types=1); |
| 2 | |
| 3 | namespace Taproot\IndieAuth; |
| 4 | |
| 5 | use BadMethodCallException; |
| 6 | use BarnabyWalters\Mf2 as M; |
| 7 | use Exception; |
| 8 | use GuzzleHttp\Psr7\Header as HeaderParser; |
| 9 | use IndieAuth\Client as IndieAuthClient; |
| 10 | use Mf2; |
| 11 | use Nyholm\Psr7\Response; |
| 12 | use PDO; |
| 13 | use Psr\Http\Client\ClientExceptionInterface; |
| 14 | use Psr\Http\Client\NetworkExceptionInterface; |
| 15 | use Psr\Http\Client\RequestExceptionInterface; |
| 16 | use Psr\Http\Message\ResponseInterface; |
| 17 | use Psr\Http\Message\ServerRequestInterface; |
| 18 | use Psr\Http\Server\MiddlewareInterface; |
| 19 | use Psr\Log\LoggerInterface; |
| 20 | use Psr\Log\NullLogger; |
| 21 | use Taproot\IndieAuth\Callback\AuthorizationFormInterface; |
| 22 | use Taproot\IndieAuth\Callback\DefaultAuthorizationForm; |
| 23 | use Taproot\IndieAuth\Storage\TokenStorageInterface; |
| 24 | |
| 25 | /** |
| 26 | * IndieAuth Server |
| 27 | * |
| 28 | * A PSR-7-compatible implementation of the request-handling logic for IndieAuth authorization endpoints |
| 29 | * and token endpoints. |
| 30 | * |
| 31 | * Typical minimal usage looks something like this: |
| 32 | * |
| 33 | * // Somewhere in your app set-up code: |
| 34 | * $server = new Taproot\IndieAuth\Server([ |
| 35 | * // A secret key, >= 64 characters long. |
| 36 | * 'secret' => YOUR_APP_INDIEAUTH_SECRET, |
| 37 | * |
| 38 | * // A path to store token data, or an object implementing TokenStorageInterface. |
| 39 | * 'tokenStorage' => '/../data/auth_tokens/', |
| 40 | * |
| 41 | * // An authentication callback function, which either returns data about the current user, |
| 42 | * // or redirects to/implements an authentication flow. |
| 43 | * 'authenticationHandler' => function (ServerRequestInterface $request, string $authenticationRedirect, ?string $normalizedMeUrl) { |
| 44 | * // If the request is authenticated, return an array with a `me` key containing the |
| 45 | * // canonical URL of the currently logged-in user. |
| 46 | * if ($userUrl = getLoggedInUserUrl($request)) { |
| 47 | * return ['me' => $userUrl]; |
| 48 | * } |
| 49 | * |
| 50 | * // Otherwise, redirect the user to a login page, ensuring that they will be redirected |
| 51 | * // back to the IndieAuth flow with query parameters intact once logged in. |
| 52 | * return new Response('302', ['Location' => 'https://example.com/login?next=' . urlencode($authenticationRedirect)]); |
| 53 | * } |
| 54 | * ]); |
| 55 | * |
| 56 | * // In your authorization endpoint route: |
| 57 | * return $server->handleAuthorizationEndpointRequest($request); |
| 58 | * |
| 59 | * // In your token endpoint route: |
| 60 | * return $server->handleTokenEndpointRequest($request); |
| 61 | * |
| 62 | * // In another route (e.g. a micropub route), to authenticate the request: |
| 63 | * // (assuming $bearerToken is a token parsed from an “Authorization: Bearer XXXXXX” header |
| 64 | * // or access_token property from a request body) |
| 65 | * if ($accessToken = $server->getTokenStorage()->getAccessToken($bearerToken)) { |
| 66 | * // Request is authenticated as $accessToken['me'], and is allowed to |
| 67 | * // act according to the scopes listed in $accessToken['scope']. |
| 68 | * $scopes = explode(' ', $accessToken['scope']); |
| 69 | * } |
| 70 | * |
| 71 | * Refer to the `__construct` documentation for further configuration options, and to the |
| 72 | * documentation for both handling methods for further documentation about them. |
| 73 | * |
| 74 | * @link https://indieauth.spec.indieweb.org/ |
| 75 | * @link https://www.rfc-editor.org/rfc/rfc6749.html#section-5.2 |
| 76 | * @link https://github.com/indieweb/indieauth-client-php |
| 77 | * @link https://github.com/Zegnat/php-mindee/blob/development/index.php |
| 78 | */ |
| 79 | class Server { |
| 80 | const HANDLE_NON_INDIEAUTH_REQUEST = 'handleNonIndieAuthRequestCallback'; |
| 81 | const HANDLE_AUTHENTICATION_REQUEST = 'authenticationHandler'; |
| 82 | |
| 83 | /** |
| 84 | * The query string parameter key used for storing the hash used for validating authorization request parameters. |
| 85 | */ |
| 86 | const HASH_QUERY_STRING_KEY = 'taproot_indieauth_server_hash'; |
| 87 | |
| 88 | /** |
| 89 | * The key used to store the CSRF token everywhere it’s used: Request parameters, Request body, and Cookies. |
| 90 | */ |
| 91 | const DEFAULT_CSRF_KEY = 'taproot_indieauth_server_csrf'; |
| 92 | |
| 93 | /** |
| 94 | * The form data key used for identifying a request as an authorization (consent screen) form submissions. |
| 95 | */ |
| 96 | const APPROVE_ACTION_KEY = 'taproot_indieauth_action'; |
| 97 | |
| 98 | /** |
| 99 | * The form data value used for identifying a request as an authorization (consent screen) form submissions. |
| 100 | */ |
| 101 | const APPROVE_ACTION_VALUE = 'approve'; |
| 102 | |
| 103 | protected Storage\TokenStorageInterface $tokenStorage; |
| 104 | |
| 105 | protected AuthorizationFormInterface $authorizationForm; |
| 106 | |
| 107 | protected MiddlewareInterface $csrfMiddleware; |
| 108 | |
| 109 | protected LoggerInterface $logger; |
| 110 | |
| 111 | /** @var callable */ |
| 112 | protected $httpGetWithEffectiveUrl; |
| 113 | |
| 114 | /** @var callable */ |
| 115 | protected $handleAuthenticationRequestCallback; |
| 116 | |
| 117 | /** @var callable */ |
| 118 | protected $handleNonIndieAuthRequest; |
| 119 | |
| 120 | protected string $exceptionTemplatePath; |
| 121 | |
| 122 | protected string $secret; |
| 123 | |
| 124 | protected bool $requirePkce; |
| 125 | |
| 126 | /** |
| 127 | * Constructor |
| 128 | * |
| 129 | * Server instances are configured by passing a config array to the constructor. |
| 130 | * |
| 131 | * The following keys are required: |
| 132 | * |
| 133 | * * `authenticationHandler`: a callable with the signature |
| 134 | * `function (ServerRequestInterface $request, string $authenticationRedirect, ?string $normalizedMeUrl): array|ResponseInterface`. |
| 135 | * This function is called on IndieAuth authorization requests, after validating the query parameters. |
| 136 | * |
| 137 | * It should check to see if $request is authenticated, then: |
| 138 | * * If it is authenticated, return an array which MUST have a `me` key, mapping to the |
| 139 | * canonical URL of the currently logged-in user. It may additionally have a `profile` key. These |
| 140 | * keys will be stored in the authorization code and sent to the client, if successful. |
| 141 | * * If it is not authenticated, either present or redirect to an authentication flow. This flow MUST |
| 142 | * redirect the logged-in used back to `$authenticationRedirect`. |
| 143 | * |
| 144 | * If the request has a valid `me` parameter, the canonicalized version of it is passed as |
| 145 | * `$normalizedMeUrl`. Otherwise, this parameter is null. This parameter can optionally be used |
| 146 | * as a suggestion for which user to log in as in a multi-user authentication flow, but should NOT |
| 147 | * be considered valid data. |
| 148 | * |
| 149 | * If redirecting to an existing authentication flow, this callable can usually be implemented as a |
| 150 | * closure. The callable may also implement its own authentication logic. For an example, see |
| 151 | * `Callback\SingleUserPasswordAuthenticationCallback`. |
| 152 | * * `secret`: A cryptographically random string with a minimum length of 64 characters. Used |
| 153 | * to hash and subsequently verify request query parameters which get passed around. |
| 154 | * * `tokenStorage`: Either an object implementing `Storage\TokenStorageInterface`, or a string path, |
| 155 | * which will be passed to `Storage\FilesystemJsonStorage`. This object handles persisting authorization |
| 156 | * codes and access tokens, as well as implementation-specific parts of the exchange process which are |
| 157 | * out of the scope of the Server class (e.g. lifetimes and expiry). Refer to the `Storage\TokenStorageInterface` |
| 158 | * documentation for more details. |
| 159 | * |
| 160 | * The following keys may be required depending on which packages you have installed: |
| 161 | * |
| 162 | * * `httpGetWithEffectiveUrl`: must be a callable with the following signature: |
| 163 | * `function (string $url): array [ResponseInterface $response, string $effectiveUrl]`, where |
| 164 | * `$effectiveUrl` is the final URL after following any redirects (unfortunately, neither the PSR-7 |
| 165 | * Response nor the PSR-18 Client interfaces offer a standard way of getting this very important |
| 166 | * data, hence the unusual return signature). If `guzzlehttp/guzzle` is installed, this parameter |
| 167 | * will be created automatically. Otherwise, the user must provide their own callable. |
| 168 | * |
| 169 | * The following keys are optional: |
| 170 | * |
| 171 | * * `authorizationForm`: an instance of `AuthorizationFormInterface`. Defaults to `DefaultAuthorizationForm`. |
| 172 | * Refer to that implementation if you wish to replace the consent screen/scope choosing/authorization form. |
| 173 | * * `csrfMiddleware`: an instance of `MiddlewareInterface`, which will be used to CSRF-protect the |
| 174 | * user-facing authorization flow. By default an instance of `DoubleSubmitCookieCsrfMiddleware`. |
| 175 | * Refer to that implementation if you want to replace it with your own middleware — you will |
| 176 | * likely have to either make sure your middleware sets the same request attribute, or alter your |
| 177 | * templates accordingly. |
| 178 | * * `exceptionTemplatePath`: string, path to a template which will be used for displaying user-facing |
| 179 | * errors. Defaults to `../templates/default_exception_response.html.php`, refer to that if you wish |
| 180 | * to write your own template. |
| 181 | * * `handleNonIndieAuthRequestCallback`: A callback with the following signature: |
| 182 | * `function (ServerRequestInterface $request): ?ResponseInterface` which will be called if the |
| 183 | * authorization endpoint gets a request which is not identified as an IndieAuth request or authorization |
| 184 | * form submission request. You could use this to handle various requests e.g. client-side requests |
| 185 | * made by your authentication or authorization pages, if it’s not convenient to put them elsewhere. |
| 186 | * Returning `null` will result in a standard `invalid_request` error being returned. |
| 187 | * * `logger`: An instance of `LoggerInterface`. Will be used for internal logging, and will also be set |
| 188 | * as the logger for any objects passed in config which implement `LoggerAwareInterface`. |
| 189 | * * `requirePKCE`: bool, default true. Setting this to `false` allows requests which don’t provide PKCE |
| 190 | * parameters (code_challenge, code_challenge_method, code_verifier), under the following conditions: |
| 191 | * * If any of the PKCE parameters are present in an authorization code request, all must be present |
| 192 | * and valid. |
| 193 | * * If an authorization code request lacks PKCE parameters, the created auth code can only be exchanged |
| 194 | * by an exchange request without parameters. |
| 195 | * * If authorization codes are stored without PKCE parameters, and then `requirePKCE` is set to `true`, |
| 196 | * these old authorization codes will no longer be redeemable. |
| 197 | * |
| 198 | * @param array $config An array of configuration variables |
| 199 | * @return self |
| 200 | */ |
| 201 | public function __construct(array $config) { |
| 202 | $config = array_merge([ |
| 203 | 'csrfMiddleware' => new Middleware\DoubleSubmitCookieCsrfMiddleware(self::DEFAULT_CSRF_KEY), |
| 204 | 'logger' => null, |
| 205 | self::HANDLE_NON_INDIEAUTH_REQUEST => function (ServerRequestInterface $request) { return null; }, // Default to no-op. |
| 206 | 'tokenStorage' => null, |
| 207 | 'httpGetWithEffectiveUrl' => null, |
| 208 | 'authorizationForm' => new DefaultAuthorizationForm(), |
| 209 | 'exceptionTemplatePath' => __DIR__ . '/../templates/default_exception_response.html.php', |
| 210 | 'requirePKCE' => true, |
| 211 | ], $config); |
| 212 | |
| 213 | $this->requirePkce = $config['requirePKCE']; |
| 214 | |
| 215 | if (!is_string($config['exceptionTemplatePath'])) { |
| 216 | throw new BadMethodCallException("\$config['exceptionTemplatePath'] must be a string (path)."); |
| 217 | } |
| 218 | $this->exceptionTemplatePath = $config['exceptionTemplatePath']; |
| 219 | |
| 220 | $secret = $config['secret'] ?? ''; |
| 221 | if (!is_string($secret) || strlen($secret) < 64) { |
| 222 | throw new BadMethodCallException("\$config['secret'] must be a string with a minimum length of 64 characters."); |
| 223 | } |
| 224 | $this->secret = $secret; |
| 225 | |
| 226 | if (!is_null($config['logger']) && !$config['logger'] instanceof LoggerInterface) { |
| 227 | throw new BadMethodCallException("\$config['logger'] must be an instance of \\Psr\\Log\\LoggerInterface or null."); |
| 228 | } |
| 229 | $this->logger = $config['logger'] ?? new NullLogger(); |
| 230 | |
| 231 | if (!(array_key_exists(self::HANDLE_AUTHENTICATION_REQUEST, $config) and is_callable($config[self::HANDLE_AUTHENTICATION_REQUEST]))) { |
| 232 | throw new BadMethodCallException('$callbacks[\'' . self::HANDLE_AUTHENTICATION_REQUEST .'\'] must be present and callable.'); |
| 233 | } |
| 234 | $this->handleAuthenticationRequestCallback = $config[self::HANDLE_AUTHENTICATION_REQUEST]; |
| 235 | |
| 236 | if (!is_callable($config[self::HANDLE_NON_INDIEAUTH_REQUEST])) { |
| 237 | throw new BadMethodCallException("\$config['" . self::HANDLE_NON_INDIEAUTH_REQUEST . "'] must be callable"); |
| 238 | } |
| 239 | $this->handleNonIndieAuthRequest = $config[self::HANDLE_NON_INDIEAUTH_REQUEST]; |
| 240 | |
| 241 | $tokenStorage = $config['tokenStorage']; |
| 242 | if (!$tokenStorage instanceof Storage\TokenStorageInterface) { |
| 243 | if (is_string($tokenStorage)) { |
| 244 | // Create a default access token storage with a TTL of 7 days. |
| 245 | $tokenStorage = new Storage\FilesystemJsonStorage($tokenStorage, $this->secret); |
| 246 | } else { |
| 247 | throw new BadMethodCallException("\$config['tokenStorage'] parameter must be either a string (path) or an instance of Taproot\IndieAuth\TokenStorageInterface."); |
| 248 | } |
| 249 | } |
| 250 | trySetLogger($tokenStorage, $this->logger); |
| 251 | $this->tokenStorage = $tokenStorage; |
| 252 | |
| 253 | $csrfMiddleware = $config['csrfMiddleware']; |
| 254 | if (!$csrfMiddleware instanceof MiddlewareInterface) { |
| 255 | throw new BadMethodCallException("\$config['csrfMiddleware'] must be null or implement MiddlewareInterface."); |
| 256 | } |
| 257 | trySetLogger($csrfMiddleware, $this->logger); |
| 258 | $this->csrfMiddleware = $csrfMiddleware; |
| 259 | |
| 260 | $httpGetWithEffectiveUrl = $config['httpGetWithEffectiveUrl']; |
| 261 | if (is_null($httpGetWithEffectiveUrl)) { |
| 262 | if (class_exists('\GuzzleHttp\Client')) { |
| 263 | $httpGetWithEffectiveUrl = function (string $uri): array { |
| 264 | // This code can’t be tested, ignore it for coverage purposes. |
| 265 | // @codeCoverageIgnoreStart |
| 266 | $resp = (new \GuzzleHttp\Client([ |
| 267 | \GuzzleHttp\RequestOptions::ALLOW_REDIRECTS => [ |
| 268 | 'max' => 10, |
| 269 | 'strict' => true, |
| 270 | 'referer' => true, |
| 271 | 'track_redirects' => true |
| 272 | ] |
| 273 | ]))->get($uri); |
| 274 | |
| 275 | $rdh = $resp->getHeader('X-Guzzle-Redirect-History'); |
| 276 | $effectiveUrl = empty($rdh) ? $uri : array_values($rdh)[count($rdh) - 1]; |
| 277 | |
| 278 | return [$resp, $effectiveUrl]; |
| 279 | }; |
| 280 | } else { |
| 281 | throw new BadMethodCallException("\$config['httpGetWithEffectiveUrl'] was not provided, and guzzlehttp/guzzle was not installed. Either require guzzlehttp/guzzle, or provide a valid callable."); |
| 282 | // @codeCoverageIgnoreEnd |
| 283 | } |
| 284 | } else { |
| 285 | if (!is_callable($httpGetWithEffectiveUrl)) { |
| 286 | throw new BadMethodCallException("\$config['httpGetWithEffectiveUrl'] must be callable."); |
| 287 | } |
| 288 | } |
| 289 | trySetLogger($httpGetWithEffectiveUrl, $this->logger); |
| 290 | $this->httpGetWithEffectiveUrl = $httpGetWithEffectiveUrl; |
| 291 | |
| 292 | if (!$config['authorizationForm'] instanceof AuthorizationFormInterface) { |
| 293 | throw new BadMethodCallException("When provided, \$config['authorizationForm'] must implement Taproot\IndieAuth\Callback\AuthorizationForm."); |
| 294 | } |
| 295 | $this->authorizationForm = $config['authorizationForm']; |
| 296 | trySetLogger($this->authorizationForm, $this->logger); |
| 297 | } |
| 298 | |
| 299 | public function getTokenStorage(): TokenStorageInterface { |
| 300 | return $this->tokenStorage; |
| 301 | } |
| 302 | |
| 303 | /** |
| 304 | * Handle Authorization Endpoint Request |
| 305 | * |
| 306 | * This method handles all requests to your authorization endpoint, passing execution off to |
| 307 | * other callbacks when necessary. The logical flow can be summarised as follows: |
| 308 | * |
| 309 | * * If this request an **auth code exchange for profile information**, validate the request |
| 310 | * and return a response or error response. |
| 311 | * * Otherwise, proceed, wrapping all execution in CSRF-protection middleware. |
| 312 | * * Validate the request’s indieauth authorization code request parameters, returning an |
| 313 | * error response if any are missing or invalid. |
| 314 | * * Call the authentication callback |
| 315 | * * If the callback returned an instance of ResponseInterface, the user is not currently |
| 316 | * logged in. Return the Response, which will presumably start an authentication flow. |
| 317 | * * Otherwise, the callback returned information about the currently logged-in user. Continue. |
| 318 | * * If this request is an authorization form submission, validate the data, store and authorization |
| 319 | * code and return a redirect response to the client redirect_uri with code data. On an error, return |
| 320 | * an appropriate error response. |
| 321 | * * Otherwise, fetch the client_id, parse app data if present, validate the `redirect_uri` and present |
| 322 | * the authorization form/consent screen to the user. |
| 323 | * * If none of the above apply, try calling the non-indieauth request handler. If it returns a Response, |
| 324 | * return that, otherwise return an error response. |
| 325 | * |
| 326 | * This route should NOT be wrapped in additional CSRF-protection, due to the need to handle API |
| 327 | * POST requests from the client. Make sure you call it from a route which is excluded from any |
| 328 | * CSRF-protection you might be using. To customise the CSRF protection used internally, refer to the |
| 329 | * `__construct` config array documentation for the `csrfMiddleware` key. |
| 330 | * |
| 331 | * Most user-facing errors are thrown as instances of `IndieAuthException`, which are passed off to |
| 332 | * `handleException` to be turned into an instance of `ResponseInterface`. If you want to customise |
| 333 | * error behaviour, one way to do so is to subclass `Server` and override that method. |
| 334 | * |
| 335 | * @param ServerRequestInterface $request |
| 336 | * @return ResponseInterface |
| 337 | */ |
| 338 | public function handleAuthorizationEndpointRequest(ServerRequestInterface $request): ResponseInterface { |
| 339 | $this->logger->info('Handling an IndieAuth Authorization Endpoint request.'); |
| 340 | |
| 341 | // If it’s a profile information request: |
| 342 | if (isIndieAuthAuthorizationCodeRedeemingRequest($request)) { |
| 343 | $this->logger->info('Handling a request to redeem an authorization code for profile information.'); |
| 344 | |
| 345 | $bodyParams = $request->getParsedBody(); |
| 346 | |
| 347 | if (!isset($bodyParams['code'])) { |
| 348 | $this->logger->warning('The exchange request was missing the code parameter. Returning an error response.'); |
| 349 | return new Response(400, ['content-type' => 'application/json'], json_encode([ |
| 350 | 'error' => 'invalid_request', |
| 351 | 'error_description' => 'The code parameter was missing.' |
| 352 | ])); |
| 353 | } |
| 354 | |
| 355 | // Attempt to internally exchange the provided auth code for an access token. |
| 356 | // We do this before anything else so that the auth code is invalidated as soon as the request starts, |
| 357 | // and the resulting access token is revoked if we encounter an error. This ends up providing a simpler |
| 358 | // and more flexible interface for TokenStorage implementors. |
| 359 | try { |
| 360 | // Call the token exchange method, passing in a callback which performs additional validation |
| 361 | // on the auth code before it gets exchanged. |
| 362 | $tokenData = $this->tokenStorage->exchangeAuthCodeForAccessToken($bodyParams['code'], function (array $authCode) use ($request, $bodyParams) { |
| 363 | // Verify that all required parameters are included. |
| 364 | $requiredParameters = ($this->requirePkce or !empty($authCode['code_challenge'])) ? ['client_id', 'redirect_uri', 'code_verifier'] : ['client_id', 'redirect_uri']; |
| 365 | $missingRequiredParameters = array_filter($requiredParameters, function ($p) use ($bodyParams) { |
| 366 | return !array_key_exists($p, $bodyParams) || empty($bodyParams[$p]); |
| 367 | }); |
| 368 | if (!empty($missingRequiredParameters)) { |
| 369 | $this->logger->warning('The exchange request was missing required parameters. Returning an error response.', ['missing' => $missingRequiredParameters]); |
| 370 | throw IndieAuthException::create(IndieAuthException::INVALID_REQUEST, $request); |
| 371 | } |
| 372 | |
| 373 | // Verify that it was issued for the same client_id and redirect_uri |
| 374 | if ($authCode['client_id'] !== $bodyParams['client_id'] |
| 375 | || $authCode['redirect_uri'] !== $bodyParams['redirect_uri']) { |
| 376 | $this->logger->error("The provided client_id and/or redirect_uri did not match those stored in the token."); |
| 377 | throw IndieAuthException::create(IndieAuthException::INVALID_GRANT, $request); |
| 378 | } |
| 379 | |
| 380 | // If the auth code was requested with no code_challenge, but the exchange request provides a |
| 381 | // code_verifier, return an error. |
| 382 | if (!empty($bodyParams['code_verifier']) && empty($authCode['code_challenge'])) { |
| 383 | $this->logger->error("A code_verifier was provided when trying to exchange an auth code requested without a code_challenge."); |
| 384 | throw IndieAuthException::create(IndieAuthException::INVALID_GRANT, $request); |
| 385 | } |
| 386 | |
| 387 | if ($this->requirePkce or !empty($authCode['code_challenge'])) { |
| 388 | // Check that the supplied code_verifier hashes to the stored code_challenge |
| 389 | // TODO: support method = plain as well as S256. |
| 390 | if (!hash_equals($authCode['code_challenge'], generatePKCECodeChallenge($bodyParams['code_verifier']))) { |
| 391 | $this->logger->error("The provided code_verifier did not hash to the stored code_challenge"); |
| 392 | throw IndieAuthException::create(IndieAuthException::INVALID_GRANT, $request); |
| 393 | } |
| 394 | } |
| 395 | |
| 396 | // Check that this token either grants at most the profile scope. |
| 397 | $requestedScopes = array_filter(explode(' ', $authCode['scope'] ?? '')); |
| 398 | if (!empty($requestedScopes) && $requestedScopes != ['profile']) { |
| 399 | $this->logger->error("An exchange request for a token granting scopes other than “profile” was sent to the authorization endpoint."); |
| 400 | throw IndieAuthException::create(IndieAuthException::INVALID_GRANT, $request); |
| 401 | } |
| 402 | }); |
| 403 | } catch (IndieAuthException $e) { |
| 404 | // If an exception was thrown, return a corresponding error response. |
| 405 | return new Response(400, ['content-type' => 'application/json'], json_encode([ |
| 406 | 'error' => $e->getInfo()['error'], |
| 407 | 'error_description' => $e->getMessage() |
| 408 | ])); |
| 409 | } |
| 410 | |
| 411 | if (is_null($tokenData)) { |
| 412 | $this->logger->error('Attempting to exchange an auth code for a token resulted in null.', $bodyParams); |
| 413 | return new Response(400, ['content-type' => 'application/json'], json_encode([ |
| 414 | 'error' => 'invalid_grant', |
| 415 | 'error_description' => 'The provided credentials were not valid.' |
| 416 | ])); |
| 417 | } |
| 418 | |
| 419 | // TODO: return an error if the token doesn’t contain a me key. |
| 420 | |
| 421 | // If everything checked out, return {"me": "https://example.com"} response |
| 422 | return new Response(200, [ |
| 423 | 'content-type' => 'application/json', |
| 424 | 'cache-control' => 'no-store', |
| 425 | ], json_encode(array_filter($tokenData, function (string $k) { |
| 426 | // Prevent codes exchanged at the authorization endpoint from returning any information other than |
| 427 | // me and profile. |
| 428 | return in_array($k, ['me', 'profile']); |
| 429 | }, ARRAY_FILTER_USE_KEY))); |
| 430 | } |
| 431 | |
| 432 | // Because the special case above isn’t allowed to be CSRF-protected, we have to do some rather silly |
| 433 | // closure gymnastics here to selectively-CSRF-protect requests which do need it. |
| 434 | return $this->csrfMiddleware->process($request, new Middleware\ClosureRequestHandler(function (ServerRequestInterface $request) { |
| 435 | // Wrap the entire user-facing handler in a try/catch block which catches any exception, converts it |
| 436 | // to IndieAuthException if necessary, then passes it to $this->handleException() to be turned into a |
| 437 | // response. |
| 438 | try { |
| 439 | $queryParams = $request->getQueryParams(); |
| 440 | |
| 441 | /** @var ResponseInterface|null $clientIdResponse */ |
| 442 | /** @var string|null $clientIdEffectiveUrl */ |
| 443 | /** @var array|null $clientIdMf2 */ |
| 444 | list($clientIdResponse, $clientIdEffectiveUrl, $clientIdMf2) = [null, null, null]; |
| 445 | |
| 446 | // If this is an authorization or approval request (allowing POST requests as well to accommodate |
| 447 | // approval requests and custom auth form submission. |
| 448 | if (isIndieAuthAuthorizationRequest($request, ['get', 'post'])) { |
| 449 | $this->logger->info('Handling an authorization request', ['method' => $request->getMethod()]); |
| 450 | |
| 451 | // Validate the Client ID. |
| 452 | if (!isset($queryParams['client_id']) || false === filter_var($queryParams['client_id'], FILTER_VALIDATE_URL) || !isClientIdentifier($queryParams['client_id'])) { |
| 453 | $this->logger->warning("The client_id provided in an authorization request was not valid.", $queryParams); |
| 454 | throw IndieAuthException::create(IndieAuthException::INVALID_CLIENT_ID, $request); |
| 455 | } |
| 456 | |
| 457 | // Validate the redirect URI. |
| 458 | if (!isset($queryParams['redirect_uri']) || false === filter_var($queryParams['redirect_uri'], FILTER_VALIDATE_URL)) { |
| 459 | $this->logger->warning("The client_id provided in an authorization request was not valid.", $queryParams); |
| 460 | throw IndieAuthException::create(IndieAuthException::INVALID_REDIRECT_URI, $request); |
| 461 | } |
| 462 | |
| 463 | // How most errors are handled depends on whether or not the request has a valid redirect_uri. In |
| 464 | // order to know that, we need to also validate, fetch and parse the client_id. |
| 465 | // If the request lacks a hash, or if the provided hash was invalid, perform the validation. |
| 466 | $currentRequestHash = hashAuthorizationRequestParameters($request, $this->secret, null, null, $this->requirePkce); |
| 467 | if (!isset($queryParams[self::HASH_QUERY_STRING_KEY]) or is_null($currentRequestHash) or !hash_equals($currentRequestHash, $queryParams[self::HASH_QUERY_STRING_KEY])) { |
| 468 | |
| 469 | // All we need to know at this stage is whether the redirect_uri is valid. If it |
| 470 | // sufficiently matches the client_id, we don’t (yet) need to fetch the client_id. |
| 471 | if (!urlComponentsMatch($queryParams['client_id'], $queryParams['redirect_uri'], [PHP_URL_SCHEME, PHP_URL_HOST, PHP_URL_PORT])) { |
| 472 | // If we do need to fetch the client_id, store the response and effective URL in variables |
| 473 | // we defined earlier, so they’re available to the approval request code path, which additionally |
| 474 | // needs to parse client_id for h-app markup. |
| 475 | try { |
| 476 | list($clientIdResponse, $clientIdEffectiveUrl) = call_user_func($this->httpGetWithEffectiveUrl, $queryParams['client_id']); |
| 477 | $clientIdMf2 = Mf2\parse((string) $clientIdResponse->getBody(), $clientIdEffectiveUrl); |
| 478 | } catch (ClientExceptionInterface | RequestExceptionInterface | NetworkExceptionInterface $e) { |
| 479 | $this->logger->error("Caught an HTTP exception while trying to fetch the client_id. Returning an error response.", [ |
| 480 | 'client_id' => $queryParams['client_id'], |
| 481 | 'exception' => $e->__toString() |
| 482 | ]); |
| 483 | |
| 484 | throw IndieAuthException::create(IndieAuthException::HTTP_EXCEPTION_FETCHING_CLIENT_ID, $request, $e); |
| 485 | } catch (Exception $e) { |
| 486 | $this->logger->error("Caught an unknown exception while trying to fetch the client_id. Returning an error response.", [ |
| 487 | 'exception' => $e->__toString() |
| 488 | ]); |
| 489 | |
| 490 | throw IndieAuthException::create(IndieAuthException::INTERNAL_EXCEPTION_FETCHING_CLIENT_ID, $request, $e); |
| 491 | } |
| 492 | |
| 493 | // Search for all link@rel=redirect_uri at the client_id. |
| 494 | $clientIdRedirectUris = []; |
| 495 | if (array_key_exists('redirect_uri', $clientIdMf2['rels'])) { |
| 496 | $clientIdRedirectUris = array_merge($clientIdRedirectUris, $clientIdMf2['rels']['redirect_uri']); |
| 497 | } |
| 498 | |
| 499 | foreach (HeaderParser::parse($clientIdResponse->getHeader('Link')) as $link) { |
| 500 | if (array_key_exists('rel', $link) && mb_strpos(" {$link['rel']} ", " redirect_uri ") !== false) { |
| 501 | // Strip off the < > which surround the link URL for some reason. |
| 502 | $clientIdRedirectUris[] = substr($link[0], 1, strlen($link[0]) - 2); |
| 503 | } |
| 504 | } |
| 505 | |
| 506 | // If the authority of the redirect_uri does not match the client_id, or exactly match one of their redirect URLs, return an error. |
| 507 | if (!in_array($queryParams['redirect_uri'], $clientIdRedirectUris)) { |
| 508 | $this->logger->warning("The provided redirect_uri did not match either the client_id, nor the discovered redirect URIs.", [ |
| 509 | 'provided_redirect_uri' => $queryParams['redirect_uri'], |
| 510 | 'provided_client_id' => $queryParams['client_id'], |
| 511 | 'discovered_redirect_uris' => $clientIdRedirectUris |
| 512 | ]); |
| 513 | |
| 514 | throw IndieAuthException::create(IndieAuthException::INVALID_REDIRECT_URI, $request); |
| 515 | } |
| 516 | } |
| 517 | } |
| 518 | |
| 519 | // From now on, we can assume that redirect_uri is valid. Any IndieAuth-related errors should be |
| 520 | // reported by redirecting to redirect_uri with error parameters. |
| 521 | |
| 522 | // Validate the state parameter. |
| 523 | if (!isset($queryParams['state']) or !isValidState($queryParams['state'])) { |
| 524 | $this->logger->warning("The state provided in an authorization request was not valid.", $queryParams); |
| 525 | throw IndieAuthException::create(IndieAuthException::INVALID_STATE, $request); |
| 526 | } |
| 527 | // From now on, any redirect error responses should include the state parameter. |
| 528 | // This is handled automatically in `handleException()` and is only noted here |
| 529 | // for reference. |
| 530 | |
| 531 | // If either PKCE parameter is present, validate both. |
| 532 | if (isset($queryParams['code_challenge']) or isset($queryParams['code_challenge_method'])) { |
| 533 | if (!isset($queryParams['code_challenge']) or !isValidCodeChallenge($queryParams['code_challenge'])) { |
| 534 | $this->logger->warning("The code_challenge provided in an authorization request was not valid.", $queryParams); |
| 535 | throw IndieAuthException::create(IndieAuthException::INVALID_CODE_CHALLENGE, $request); |
| 536 | } |
| 537 | |
| 538 | if (!isset($queryParams['code_challenge_method']) or !in_array($queryParams['code_challenge_method'], ['S256', 'plain'])) { |
| 539 | $this->logger->error("The code_challenge_method parameter was missing or invalid.", $queryParams); |
| 540 | throw IndieAuthException::create(IndieAuthException::INVALID_CODE_CHALLENGE, $request); |
| 541 | } |
| 542 | } else { |
| 543 | // If neither PKCE parameter is defined, and PKCE is required, throw an error. Otherwise, proceed. |
| 544 | if ($this->requirePkce) { |
| 545 | $this->logger->warning("PKCE is required, and both code_challenge and code_challenge_method were missing."); |
| 546 | throw IndieAuthException::create(IndieAuthException::INVALID_REQUEST_REDIRECT, $request); |
| 547 | } |
| 548 | } |
| 549 | |
| 550 | // Validate the scope parameter, if provided. |
| 551 | if (array_key_exists('scope', $queryParams) && !isValidScope($queryParams['scope'])) { |
| 552 | $this->logger->warning("The scope provided in an authorization request was not valid.", $queryParams); |
| 553 | throw IndieAuthException::create(IndieAuthException::INVALID_SCOPE, $request); |
| 554 | } |
| 555 | |
| 556 | // Normalise the me parameter, if it exists. |
| 557 | if (array_key_exists('me', $queryParams)) { |
| 558 | $queryParams['me'] = IndieAuthClient::normalizeMeURL($queryParams['me']); |
| 559 | // If the me parameter is not a valid profile URL, ignore it. |
| 560 | if (false === $queryParams['me'] || !isProfileUrl($queryParams['me'])) { |
| 561 | $queryParams['me'] = null; |
| 562 | } |
| 563 | } |
| 564 | |
| 565 | // Build a URL containing the indieauth authorization request parameters, hashing them |
| 566 | // to protect them from being changed. |
| 567 | // Make a hash of the protected indieauth-specific parameters. If PKCE is in use, include |
| 568 | // the PKCE parameters in the hash. Otherwise, leave them out. |
| 569 | $hash = hashAuthorizationRequestParameters($request, $this->secret, null, null, $this->requirePkce); |
| 570 | // Operate on a copy of $queryParams, otherwise requests will always have a valid hash! |
| 571 | $redirectQueryParams = $queryParams; |
| 572 | $redirectQueryParams[self::HASH_QUERY_STRING_KEY] = $hash; |
| 573 | $authenticationRedirect = $request->getUri()->withQuery(buildQueryString($redirectQueryParams))->__toString(); |
| 574 | |
| 575 | // User-facing requests always start by calling the authentication request callback. |
| 576 | $this->logger->info('Calling handle_authentication_request callback'); |
| 577 | $authenticationResult = call_user_func($this->handleAuthenticationRequestCallback, $request, $authenticationRedirect, $queryParams['me'] ?? null); |
| 578 | |
| 579 | // If the authentication handler returned a Response, return that as-is. |
| 580 | if ($authenticationResult instanceof ResponseInterface) { |
| 581 | return $authenticationResult; |
| 582 | } elseif (is_array($authenticationResult)) { |
| 583 | // Check the resulting array for errors. |
| 584 | if (!array_key_exists('me', $authenticationResult)) { |
| 585 | $this->logger->error('The handle_authentication_request callback returned an array with no me key.', ['array' => $authenticationResult]); |
| 586 | throw IndieAuthException::create(IndieAuthException::AUTHENTICATION_CALLBACK_MISSING_ME_PARAM, $request); |
| 587 | } |
| 588 | |
| 589 | // If this is a POST request sent from the authorization (i.e. scope-choosing) form: |
| 590 | if (isAuthorizationApprovalRequest($request)) { |
| 591 | // Authorization approval requests MUST include a hash protecting the sensitive IndieAuth |
| 592 | // authorization request parameters from being changed, e.g. by a malicious script which |
| 593 | // found its way onto the authorization form. |
| 594 | if (!array_key_exists(self::HASH_QUERY_STRING_KEY, $queryParams)) { |
| 595 | $this->logger->warning("An authorization approval request did not have a " . self::HASH_QUERY_STRING_KEY . " parameter."); |
| 596 | throw IndieAuthException::create(IndieAuthException::AUTHORIZATION_APPROVAL_REQUEST_MISSING_HASH, $request); |
| 597 | } |
| 598 | |
| 599 | $expectedHash = hashAuthorizationRequestParameters($request, $this->secret, null, null, $this->requirePkce); |
| 600 | if (!isset($queryParams[self::HASH_QUERY_STRING_KEY]) or is_null($expectedHash) or !hash_equals($expectedHash, $queryParams[self::HASH_QUERY_STRING_KEY])) { |
| 601 | $this->logger->warning("The hash provided in the URL was invalid!", [ |
| 602 | 'expected' => $expectedHash, |
| 603 | 'actual' => $queryParams[self::HASH_QUERY_STRING_KEY] |
| 604 | ]); |
| 605 | throw IndieAuthException::create(IndieAuthException::AUTHORIZATION_APPROVAL_REQUEST_INVALID_HASH, $request); |
| 606 | } |
| 607 | |
| 608 | // Assemble the data for the authorization code, store it somewhere persistent. |
| 609 | $code = array_merge($authenticationResult, [ |
| 610 | 'client_id' => $queryParams['client_id'], |
| 611 | 'redirect_uri' => $queryParams['redirect_uri'], |
| 612 | 'state' => $queryParams['state'], |
| 613 | 'code_challenge' => $queryParams['code_challenge'] ?? null, |
| 614 | 'code_challenge_method' => $queryParams['code_challenge_method'] ?? null, |
| 615 | 'requested_scope' => $queryParams['scope'] ?? '', |
| 616 | ]); |
| 617 | |
| 618 | // Pass it to the auth code customisation callback. |
| 619 | $code = $this->authorizationForm->transformAuthorizationCode($request, $code); |
| 620 | $this->logger->info("Creating an authorization code:", ['data' => $code]); |
| 621 | |
| 622 | // Store the authorization code. |
| 623 | $authCode = $this->tokenStorage->createAuthCode($code); |
| 624 | if (is_null($authCode)) { |
| 625 | // If saving the authorization code failed silently, there isn’t much we can do about it, |
| 626 | // but should at least log and return an error. |
| 627 | $this->logger->error("Saving the authorization code failed and returned false without raising an exception."); |
| 628 | throw IndieAuthException::create(IndieAuthException::INTERNAL_ERROR_REDIRECT, $request); |
| 629 | } |
| 630 | |
| 631 | // Return a redirect to the client app. |
| 632 | return new Response(302, [ |
| 633 | 'Location' => appendQueryParams($queryParams['redirect_uri'], [ |
| 634 | 'code' => $authCode, |
| 635 | 'state' => $code['state'] |
| 636 | ]), |
| 637 | 'Cache-control' => 'no-cache' |
| 638 | ]); |
| 639 | } |
| 640 | |
| 641 | // Otherwise, the user is authenticated and needs to authorize the client app + choose scopes. |
| 642 | |
| 643 | // Fetch the client_id URL to find information about the client to present to the user. |
| 644 | // TODO: in order to comply with https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.2.1, |
| 645 | // it may be necessary to do this before returning any other kind of error response, as, per |
| 646 | // the spec, errors should only be shown to the user if the client_id and redirect_uri parameters |
| 647 | // are missing or invalid. Otherwise, they should be sent back to the client with an error |
| 648 | // redirect response. |
| 649 | if (is_null($clientIdResponse) || is_null($clientIdEffectiveUrl) || is_null($clientIdMf2)) { |
| 650 | try { |
| 651 | /** @var ResponseInterface $clientIdResponse */ |
| 652 | list($clientIdResponse, $clientIdEffectiveUrl) = call_user_func($this->httpGetWithEffectiveUrl, $queryParams['client_id']); |
| 653 | $clientIdMf2 = Mf2\parse((string) $clientIdResponse->getBody(), $clientIdEffectiveUrl); |
| 654 | } catch (ClientExceptionInterface | RequestExceptionInterface | NetworkExceptionInterface $e) { |
| 655 | $this->logger->error("Caught an HTTP exception while trying to fetch the client_id. Returning an error response.", [ |
| 656 | 'client_id' => $queryParams['client_id'], |
| 657 | 'exception' => $e->__toString() |
| 658 | ]); |
| 659 | |
| 660 | // At this point in the flow, we’ve already guaranteed that the redirect_uri is valid, |
| 661 | // so in theory we should report these errors by redirecting there. |
| 662 | throw IndieAuthException::create(IndieAuthException::INTERNAL_ERROR_REDIRECT, $request, $e); |
| 663 | } catch (Exception $e) { |
| 664 | $this->logger->error("Caught an unknown exception while trying to fetch the client_id. Returning an error response.", [ |
| 665 | 'exception' => $e->__toString() |
| 666 | ]); |
| 667 | |
| 668 | throw IndieAuthException::create(IndieAuthException::INTERNAL_ERROR_REDIRECT, $request, $e); |
| 669 | } |
| 670 | } |
| 671 | |
| 672 | // Search for an h-app with u-url matching the client_id. |
| 673 | $clientHApps = M\findMicroformatsByProperty(M\findMicroformatsByType($clientIdMf2, 'h-app'), 'url', $queryParams['client_id']); |
| 674 | $clientHApp = empty($clientHApps) ? null : $clientHApps[0]; |
| 675 | |
| 676 | // Present the authorization UI. |
| 677 | return $this->authorizationForm->showForm($request, $authenticationResult, $authenticationRedirect, $clientHApp) |
| 678 | ->withAddedHeader('Cache-control', 'no-cache'); |
| 679 | } |
| 680 | } |
| 681 | |
| 682 | // If the request isn’t an IndieAuth Authorization or Code-redeeming request, it’s either an invalid |
| 683 | // request or something to do with a custom auth handler (e.g. sending a one-time code in an email.) |
| 684 | $nonIndieAuthRequestResult = call_user_func($this->handleNonIndieAuthRequest, $request); |
| 685 | if ($nonIndieAuthRequestResult instanceof ResponseInterface) { |
| 686 | return $nonIndieAuthRequestResult; |
| 687 | } else { |
| 688 | // In this code path we have not validated the redirect_uri, so show a regular error page |
| 689 | // rather than returning a redirect error. |
| 690 | throw IndieAuthException::create(IndieAuthException::INTERNAL_ERROR, $request); |
| 691 | } |
| 692 | } catch (IndieAuthException $e) { |
| 693 | // All IndieAuthExceptions will already have been logged. |
| 694 | return $this->handleException($e); |
| 695 | } catch (Exception $e) { |
| 696 | // Unknown exceptions will not have been logged; do so now. |
| 697 | $this->logger->error("Caught unknown exception: {$e}"); |
| 698 | return $this->handleException(IndieAuthException::create(0, $request, $e)); |
| 699 | } |
| 700 | })); |
| 701 | } |
| 702 | |
| 703 | /** |
| 704 | * Handle Token Endpoint Request |
| 705 | * |
| 706 | * Handles requests to the IndieAuth token endpoint. The logical flow can be summarised as follows: |
| 707 | * |
| 708 | * * Check that the request is a code redeeming request. Return an error if not. |
| 709 | * * Ensure that all required parameters are present. Return an error if not. |
| 710 | * * Attempt to exchange the `code` parameter for an access token. Return an error if it fails. |
| 711 | * * Make sure the client_id and redirect_uri request parameters match those stored in the auth code. If not, revoke the access token and return an error. |
| 712 | * * Make sure the provided code_verifier hashes to the code_challenge stored in the auth code. If not, revoke the access token and return an error. |
| 713 | * * Make sure the granted scope stored in the auth code is not empty. If it is, revoke the access token and return an error. |
| 714 | * * Otherwise, return a success response containing information about the issued access token. |
| 715 | * |
| 716 | * This method must NOT be CSRF-protected as it accepts external requests from client apps. |
| 717 | * |
| 718 | * @param ServerRequestInterface $request |
| 719 | * @return ResponseInterface |
| 720 | */ |
| 721 | public function handleTokenEndpointRequest(ServerRequestInterface $request): ResponseInterface { |
| 722 | if (isIndieAuthAuthorizationCodeRedeemingRequest($request)) { |
| 723 | $this->logger->info('Handling a request to redeem an authorization code for an access token.'); |
| 724 | |
| 725 | $bodyParams = $request->getParsedBody(); |
| 726 | |
| 727 | if (!isset($bodyParams['code'])) { |
| 728 | $this->logger->warning('The exchange request was missing the code parameter. Returning an error response.'); |
| 729 | return new Response(400, ['content-type' => 'application/json'], json_encode([ |
| 730 | 'error' => 'invalid_request', |
| 731 | 'error_description' => 'The code parameter was missing.' |
| 732 | ])); |
| 733 | } |
| 734 | |
| 735 | // Attempt to internally exchange the provided auth code for an access token. |
| 736 | // We do this before anything else so that the auth code is invalidated as soon as the request starts, |
| 737 | // and the resulting access token is revoked if we encounter an error. This ends up providing a simpler |
| 738 | // and more flexible interface for TokenStorage implementors. |
| 739 | try { |
| 740 | // Call the token exchange method, passing in a callback which performs additional validation |
| 741 | // on the auth code before it gets exchanged. |
| 742 | $tokenData = $this->tokenStorage->exchangeAuthCodeForAccessToken($bodyParams['code'], function (array $authCode) use ($request, $bodyParams) { |
| 743 | // Verify that all required parameters are included. |
| 744 | $requiredParameters = ($this->requirePkce or !empty($authCode['code_challenge'])) ? ['client_id', 'redirect_uri', 'code_verifier'] : ['client_id', 'redirect_uri']; |
| 745 | $missingRequiredParameters = array_filter($requiredParameters, function ($p) use ($bodyParams) { |
| 746 | return !array_key_exists($p, $bodyParams) || empty($bodyParams[$p]); |
| 747 | }); |
| 748 | if (!empty($missingRequiredParameters)) { |
| 749 | $this->logger->warning('The exchange request was missing required parameters. Returning an error response.', ['missing' => $missingRequiredParameters]); |
| 750 | throw IndieAuthException::create(IndieAuthException::INVALID_REQUEST, $request); |
| 751 | } |
| 752 | |
| 753 | // Verify that it was issued for the same client_id and redirect_uri |
| 754 | if ($authCode['client_id'] !== $bodyParams['client_id'] |
| 755 | || $authCode['redirect_uri'] !== $bodyParams['redirect_uri']) { |
| 756 | $this->logger->error("The provided client_id and/or redirect_uri did not match those stored in the token."); |
| 757 | throw IndieAuthException::create(IndieAuthException::INVALID_GRANT, $request); |
| 758 | } |
| 759 | |
| 760 | // If the auth code was requested with no code_challenge, but the exchange request provides a |
| 761 | // code_verifier, return an error. |
| 762 | if (!empty($bodyParams['code_verifier']) && empty($authCode['code_challenge'])) { |
| 763 | $this->logger->error("A code_verifier was provided when trying to exchange an auth code requested without a code_challenge."); |
| 764 | throw IndieAuthException::create(IndieAuthException::INVALID_GRANT, $request); |
| 765 | } |
| 766 | |
| 767 | if ($this->requirePkce or !empty($authCode['code_challenge'])) { |
| 768 | // Check that the supplied code_verifier hashes to the stored code_challenge |
| 769 | // TODO: support method = plain as well as S256. |
| 770 | if (!hash_equals($authCode['code_challenge'], generatePKCECodeChallenge($bodyParams['code_verifier']))) { |
| 771 | $this->logger->error("The provided code_verifier did not hash to the stored code_challenge"); |
| 772 | throw IndieAuthException::create(IndieAuthException::INVALID_GRANT, $request); |
| 773 | } |
| 774 | } |
| 775 | |
| 776 | // Check that scope is not empty. |
| 777 | if (empty($authCode['scope'])) { |
| 778 | $this->logger->error("An exchange request for a token with an empty scope was sent to the token endpoint."); |
| 779 | throw IndieAuthException::create(IndieAuthException::INVALID_GRANT, $request); |
| 780 | } |
| 781 | }); |
| 782 | } catch (IndieAuthException $e) { |
| 783 | // If an exception was thrown, return a corresponding error response. |
| 784 | return new Response(400, ['content-type' => 'application/json'], json_encode([ |
| 785 | 'error' => $e->getInfo()['error'], |
| 786 | 'error_description' => $e->getMessage() |
| 787 | ])); |
| 788 | } |
| 789 | |
| 790 | if (is_null($tokenData)) { |
| 791 | $this->logger->error('Attempting to exchange an auth code for a token resulted in null.', $bodyParams); |
| 792 | return new Response(400, ['content-type' => 'application/json'], json_encode([ |
| 793 | 'error' => 'invalid_grant', |
| 794 | 'error_description' => 'The provided credentials were not valid.' |
| 795 | ])); |
| 796 | } |
| 797 | |
| 798 | // TODO: return an error if the token doesn’t contain a me key. |
| 799 | |
| 800 | // If everything checked out, return {"me": "https://example.com"} response |
| 801 | return new Response(200, [ |
| 802 | 'content-type' => 'application/json', |
| 803 | 'cache-control' => 'no-store', |
| 804 | ], json_encode(array_merge([ |
| 805 | // Ensure that the token_type key is present, if tokenStorage doesn’t include it. |
| 806 | 'token_type' => 'Bearer' |
| 807 | ], array_filter($tokenData, function (string $k) { |
| 808 | // We should be able to trust the return data from tokenStorage, but there’s no harm in |
| 809 | // preventing code_challenges from leaking, per OAuth2. |
| 810 | return !in_array($k, ['code_challenge', 'code_challenge_method']); |
| 811 | }, ARRAY_FILTER_USE_KEY)))); |
| 812 | } |
| 813 | |
| 814 | return new Response(400, ['content-type' => 'application/json'], json_encode([ |
| 815 | 'error' => 'invalid_request', |
| 816 | 'error_description' => 'Request to token endpoint was not a valid code exchange request.' |
| 817 | ])); |
| 818 | } |
| 819 | |
| 820 | /** |
| 821 | * Handle Exception |
| 822 | * |
| 823 | * Turns an instance of `IndieAuthException` into an appropriate instance of `ResponseInterface`. |
| 824 | */ |
| 825 | protected function handleException(IndieAuthException $exception): ResponseInterface { |
| 826 | $exceptionData = $exception->getInfo(); |
| 827 | |
| 828 | if ($exceptionData['statusCode'] == 302) { |
| 829 | // This exception is handled by redirecting to the redirect_uri with error parameters. |
| 830 | $redirectQueryParams = [ |
| 831 | 'error' => $exceptionData['error'] ?? 'invalid_request', |
| 832 | 'error_description' => (string) $exception |
| 833 | ]; |
| 834 | |
| 835 | // If the state parameter was valid, include it in the error redirect. |
| 836 | if ($exception->getCode() !== IndieAuthException::INVALID_STATE) { |
| 837 | $redirectQueryParams['state'] = $exception->getRequest()->getQueryParams()['state']; |
| 838 | } |
| 839 | |
| 840 | return new Response($exceptionData['statusCode'], [ |
| 841 | 'Location' => appendQueryParams((string) $exception->getRequest()->getQueryParams()['redirect_uri'], $redirectQueryParams) |
| 842 | ]); |
| 843 | } else { |
| 844 | // This exception should be shown to the user. |
| 845 | return new Response($exception->getStatusCode(), ['content-type' => 'text/html'], renderTemplate($this->exceptionTemplatePath, [ |
| 846 | 'request' => $exception->getRequest(), |
| 847 | 'exception' => $exception |
| 848 | ])); |
| 849 | } |
| 850 | } |
| 851 | } |