Skip to content

[Cache] Fix key encoding issue in Memcached adapter #38108

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Sep 9, 2020
Merged

[Cache] Fix key encoding issue in Memcached adapter #38108

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
36 changes: 34 additions & 2 deletions src/Symfony/Component/Cache/Tests/Adapter/MemcachedAdapterTest.php
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -42,11 +42,11 @@ public static function setUpBeforeClass(): void
}
}

public function createCachePool(int $defaultLifetime = 0): CacheItemPoolInterface
public function createCachePool(int $defaultLifetime = 0, string $testMethod = null, string $namespace = null): CacheItemPoolInterface
{
$client = $defaultLifetime ? AbstractAdapter::createConnection('memcached://'.getenv('MEMCACHED_HOST')) : self::$client;

return new MemcachedAdapter($client, str_replace('\\', '.', __CLASS__), $defaultLifetime);
return new MemcachedAdapter($client, $namespace ?? str_replace('\\', '.', __CLASS__), $defaultLifetime);
}

public function testOptions()
Expand Down Expand Up @@ -248,4 +248,36 @@ public function testMultiServerDsn()
];
$this->assertSame($expected, $client->getServerList());
}

public function testKeyEncoding()
{
$reservedMemcachedCharacters = " \n\r\t\v\f\0";

$namespace = $reservedMemcachedCharacters.random_int(0, \PHP_INT_MAX);
$pool = $this->createCachePool(0, null, $namespace);

/**
* Choose a key that is below {@see \Symfony\Component\Cache\Adapter\MemcachedAdapter::$maxIdLength} so that
* {@see \Symfony\Component\Cache\Traits\AbstractTrait::getId()} does not shorten the key but choose special
* characters that would be encoded and therefore increase the key length over the Memcached limit.
*/
// 250 is Memcached’s max key length, 7 bytes for prefix seed
$key = str_repeat('%', 250 - 7 - \strlen($reservedMemcachedCharacters) - \strlen($namespace)).$reservedMemcachedCharacters;

self::assertFalse($pool->hasItem($key));

$item = $pool->getItem($key);
self::assertFalse($item->isHit());
self::assertSame($key, $item->getKey());

self::assertTrue($pool->save($item->set('foobar')));

self::assertTrue($pool->hasItem($key));
$item = $pool->getItem($key);
self::assertTrue($item->isHit());
self::assertSame($key, $item->getKey());

self::assertTrue($pool->deleteItem($key));
self::assertFalse($pool->hasItem($key));
}
}
28 changes: 23 additions & 5 deletions src/Symfony/Component/Cache/Traits/MemcachedTrait.php
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,14 @@ trait MemcachedTrait
\Memcached::OPT_SERIALIZER => \Memcached::SERIALIZER_PHP,
];

/**
* We are replacing characters that are illegal in Memcached keys with reserved characters from
* {@see \Symfony\Contracts\Cache\ItemInterface::RESERVED_CHARACTERS} that are legal in Memcached.
* Note: don’t use {@see \Symfony\Component\Cache\Adapter\AbstractAdapter::NS_SEPARATOR}.
*/
private static $RESERVED_MEMCACHED = " \n\r\t\v\f\0";
private static $RESERVED_PSR6 = '@()\{}/';

private $marshaller;
private $client;
private $lazyClient;
Expand Down Expand Up @@ -235,7 +243,7 @@ protected function doSave(array $values, int $lifetime)

$encodedValues = [];
foreach ($values as $key => $value) {
$encodedValues[rawurlencode($key)] = $value;
$encodedValues[self::encodeKey($key)] = $value;
}

return $this->checkResultCode($this->getClient()->setMulti($encodedValues, $lifetime)) ? $failed : false;
Expand All @@ -247,13 +255,13 @@ protected function doSave(array $values, int $lifetime)
protected function doFetch(array $ids)
{
try {
$encodedIds = array_map('rawurlencode', $ids);
$encodedIds = array_map('self::encodeKey', $ids);

$encodedResult = $this->checkResultCode($this->getClient()->getMulti($encodedIds));

$result = [];
foreach ($encodedResult as $key => $value) {
$result[rawurldecode($key)] = $this->marshaller->unmarshall($value);
$result[self::decodeKey($key)] = $this->marshaller->unmarshall($value);
}

return $result;
Expand All @@ -267,7 +275,7 @@ protected function doFetch(array $ids)
*/
protected function doHave($id)
{
return false !== $this->getClient()->get(rawurlencode($id)) || $this->checkResultCode(\Memcached::RES_SUCCESS === $this->client->getResultCode());
return false !== $this->getClient()->get(self::encodeKey($id)) || $this->checkResultCode(\Memcached::RES_SUCCESS === $this->client->getResultCode());
}

/**
Expand All @@ -276,7 +284,7 @@ protected function doHave($id)
protected function doDelete(array $ids)
{
$ok = true;
$encodedIds = array_map('rawurlencode', $ids);
$encodedIds = array_map('self::encodeKey', $ids);
foreach ($this->checkResultCode($this->getClient()->deleteMulti($encodedIds)) as $result) {
if (\Memcached::RES_SUCCESS !== $result && \Memcached::RES_NOTFOUND !== $result) {
$ok = false;
Expand Down Expand Up @@ -322,4 +330,14 @@ private function getClient(): \Memcached

return $this->client = $this->lazyClient;
}

private static function encodeKey(string $key): string
{
return strtr($key, self::$RESERVED_MEMCACHED, self::$RESERVED_PSR6);
}

private static function decodeKey(string $key): string
{
return strtr($key, self::$RESERVED_PSR6, self::$RESERVED_MEMCACHED);
}
}