bug symfony#17287 [HttpKernel] Forcing string comparison on query parameters sort in UriSigner (Tim van Densen)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes symfony#17287).

Discussion
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[HttpKernel] Forcing string comparison on query parameters sort in UriSigner

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

The signing of an url fails when using query parameters with integers as keys.
The ksort function in the ```UriSigner``` class changes the order of the query params and causes to generate a different hash which results in a failed check.

In this PR we force a string comparison for ksort which keeps the correct order of parameters.

Commits
-------

2040139 Added sort order SORT_STRING for params in UriSigner

Author: fabpot

src/Symfony/Component/HttpKernel/Tests/UriSignerTest.php

@@ -33,6 +33,7 @@ public function testCheck()
 
         $this->assertTrue($signer->check($signer->sign('http://example.com/foo')));
         $this->assertTrue($signer->check($signer->sign('http://example.com/foo?foo=bar')));
+        $this->assertTrue($signer->check($signer->sign('http://example.com/foo?foo=bar&0=integer')));
 
         $this->assertTrue($signer->sign('http://example.com/foo?foo=bar&bar=foo') === $signer->sign('http://example.com/foo?bar=foo&foo=bar'));
     }

src/Symfony/Component/HttpKernel/UriSigner.php

@@ -91,8 +91,8 @@ private function computeHash($uri)
 
     private function buildUrl(array $url, array $params = array())
     {
-        ksort($params);
-        $url['query'] = http_build_query($params);
+        ksort($params, SORT_STRING);
+        $url['query'] = http_build_query($params, '', '&');
 
         $scheme = isset($url['scheme']) ? $url['scheme'].'://' : '';
         $host = isset($url['host']) ? $url['host'] : '';