Fix tests for nested v4 in v6

Signed-off-by: Côme Chilliet <come.chilliet@nextcloud.com>

lib/private/Http/Client/LocalAddressChecker.php

@@ -25,6 +25,7 @@ declare(strict_types=1);
  */
 namespace OC\Http\Client;
 
+use IPLib\Address\IPv6;
 use IPLib\Factory;
 use IPLib\ParseStringFlag;
 use OCP\Http\Client\LocalServerException;
@@ -48,7 +49,11 @@ class LocalAddressChecker {
 			return;
 		}
 		/* Replace by normalized form */
-		$ip = (string)$parsedIp;
+		if ($parsedIp instanceof IPv6) {
+			$ip = (string)($parsedIp->toIPv4() ?? $parsedIp);
+		} else {
+			$ip = (string)$parsedIp;
+		}
 
 		$localRanges = [
 			'100.64.0.0/10', // See RFC 6598
@@ -63,19 +68,6 @@ class LocalAddressChecker {
 			$this->logger->warning("Host $ip was not connected to because it violates local access rules");
 			throw new LocalServerException('Host violates local access rules');
 		}
-
-		// Also check for IPv6 IPv4 nesting, because that's not covered by filter_var
-		if ((bool)filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6) && substr_count($ip, '.') > 0) {
-			$delimiter = strrpos($ip, ':'); // Get last colon
-			$ipv4Address = substr($ip, $delimiter + 1);
-
-			if (
-				!filter_var($ipv4Address, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE) ||
-				IpUtils::checkIp($ip, $localRanges)) {
-				$this->logger->warning("Host $ip was not connected to because it violates local access rules");
-				throw new LocalServerException('Host violates local access rules');
-			}
-		}
 	}
 
 	public function ThrowIfLocalAddress(string $uri) : void {

tests/lib/Http/Client/LocalAddressCheckerTest.php

@@ -91,7 +91,7 @@ class LocalAddressCheckerTest extends \Test\TestCase {
 		return [
 			['192.168.0.1'],
 			['fe80::200:5aee:feaa:20a2'],
-			['0:0:0:0:0:0:10.0.0.1'],
+			['0:0:0:0:0:ffff:10.0.0.1'],
 			['0:0:0:0:0:ffff:127.0.0.0'],
 			['10.0.0.1'],
 			['::'],
@@ -112,7 +112,7 @@ class LocalAddressCheckerTest extends \Test\TestCase {
 			['172.16.42.1'],
 			['[fdf8:f53b:82e4::53]/secret.ics'],
 			['[fe80::200:5aee:feaa:20a2]/secret.ics'],
-			['[0:0:0:0:0:0:10.0.0.1]/secret.ics'],
+			['[0:0:0:0:0:ffff:10.0.0.1]/secret.ics'],
 			['[0:0:0:0:0:ffff:127.0.0.0]/secret.ics'],
 			['10.0.0.1'],
 			['another-host.local'],