diff --git a/src/Symfony/Component/HttpKernel/HttpCache/Store.php b/src/Symfony/Component/HttpKernel/HttpCache/Store.php index fd04a7b23d1d3..7bfdade3a8738 100644 --- a/src/Symfony/Component/HttpKernel/HttpCache/Store.php +++ b/src/Symfony/Component/HttpKernel/HttpCache/Store.php @@ -152,8 +152,8 @@ public function lookup(Request $request) } $headers = $match[1]; - if (file_exists($body = $this->getPath($headers['x-content-digest'][0]))) { - return $this->restoreResponse($headers, $body); + if (file_exists($path = $this->getPath($headers['x-content-digest'][0]))) { + return $this->restoreResponse($headers, $path); } // TODO the metaStore referenced an entity that doesn't exist in @@ -177,15 +177,28 @@ public function write(Request $request, Response $response) $key = $this->getCacheKey($request); $storedEnv = $this->persistRequest($request); - $digest = $this->generateContentDigest($response); - $response->headers->set('X-Content-Digest', $digest); + if ($response->headers->has('X-Body-File')) { + // Assume the response came from disk, but at least perform some safeguard checks + if (!$response->headers->has('X-Content-Digest')) { + throw new \RuntimeException('A restored response must have the X-Content-Digest header'); + } - if (!$this->save($digest, $response->getContent(), false)) { - throw new \RuntimeException('Unable to store the entity.'); - } + $digest = $response->headers->get('X-Content-Digest'); + if ($this->getPath($digest) !== $response->headers->get('X-Body-File')) { + throw new \RuntimeException('X-Body-File and X-Content-Digest do not match'); + } + // Everything seems ok, omit writing content to disk + } else { + $digest = $this->generateContentDigest($response); + $response->headers->set('X-Content-Digest', $digest); - if (!$response->headers->has('Transfer-Encoding')) { - $response->headers->set('Content-Length', \strlen($response->getContent())); + if (!$this->save($digest, $response->getContent(), false)) { + throw new \RuntimeException('Unable to store the entity.'); + } + + if (!$response->headers->has('Transfer-Encoding')) { + $response->headers->set('Content-Length', \strlen($response->getContent())); + } } // read existing cache entries, remove non-varying, and add this one to the list @@ -477,19 +490,19 @@ private function persistResponse(Response $response) * Restores a Response from the HTTP headers and body. * * @param array $headers An array of HTTP headers for the Response - * @param string $body The Response body + * @param string $path Path to the Response body * * @return Response */ - private function restoreResponse($headers, $body = null) + private function restoreResponse($headers, $path = null) { $status = $headers['X-Status'][0]; unset($headers['X-Status']); - if (null !== $body) { - $headers['X-Body-File'] = [$body]; + if (null !== $path) { + $headers['X-Body-File'] = [$path]; } - return new Response($body, $status, $headers); + return new Response($path, $status, $headers); } } diff --git a/src/Symfony/Component/HttpKernel/Tests/HttpCache/StoreTest.php b/src/Symfony/Component/HttpKernel/Tests/HttpCache/StoreTest.php index 07c41542697e3..6754be45a13aa 100644 --- a/src/Symfony/Component/HttpKernel/Tests/HttpCache/StoreTest.php +++ b/src/Symfony/Component/HttpKernel/Tests/HttpCache/StoreTest.php @@ -118,6 +118,39 @@ public function testWritesResponseEvenIfXContentDigestIsPresent() $this->assertNotNull($response); } + public function testWritingARestoredResponseDoesNotCorruptCache() + { + /* + * This covers the regression reported in https://github.com/symfony/symfony/issues/37174. + * + * A restored response does *not* load the body, but only keep the file path in a special X-Body-File + * header. For reasons (?), the file path was also used as the restored response body. + * It would be up to others (HttpCache...?) to hohor this header and actually load the response content + * from there. + * + * When a restored response was stored again, the Store itself would ignore the header. In the first + * step, this would compute a new Content Digest based on the file path in the restored response body; + * this is covered by "Checkpoint 1" below. But, since the X-Body-File header was left untouched (Checkpoint 2), downstream + * code (HttpCache...) would not immediately notice. + * + * Only upon performing the lookup for a second time, we'd get a Response where the (wrong) Content Digest + * is also reflected in the X-Body-File header, this time also producing wrong content when the downstream + * evaluates it. + */ + $this->store->write($this->request, $this->response); + $digest = $this->response->headers->get('X-Content-Digest'); + $path = $this->getStorePath($digest); + + $response = $this->store->lookup($this->request); + $this->store->write($this->request, $response); + $this->assertEquals($digest, $response->headers->get('X-Content-Digest')); // Checkpoint 1 + $this->assertEquals($path, $response->headers->get('X-Body-File')); // Checkpoint 2 + + $response = $this->store->lookup($this->request); + $this->assertEquals($digest, $response->headers->get('X-Content-Digest')); + $this->assertEquals($path, $response->headers->get('X-Body-File')); + } + public function testFindsAStoredEntryWithLookup() { $this->storeSimpleEntry();