Add public API to give developers the possibility to adjust the global CSP defaults

Allows to inject something into the default content policy. This is for
example useful when you're injecting Javascript code into a view belonging
to another controller and cannot modify its Content-Security-Policy itself.
Note that the adjustment is only applied to applications that use AppFramework
controllers.

To use this from your `app.php` use `\OC::$server->getContentSecurityPolicyManager()->addDefaultPolicy($policy)`,
$policy has to be of type `\OCP\AppFramework\Http\ContentSecurityPolicy`.

To test this add something like the following into an `app.php` of any enabled app:
```
$manager = \OC::$server->getContentSecurityPolicyManager();
$policy = new \OCP\AppFramework\Http\ContentSecurityPolicy(false);
$policy->addAllowedFrameDomain('asdf');
$policy->addAllowedScriptDomain('yolo.com');

$policy->allowInlineScript(false);
$manager->addDefaultPolicy($policy);
$policy = new \OCP\AppFramework\Http\ContentSecurityPolicy(false);
$policy->addAllowedFontDomain('yolo.com');
$manager->addDefaultPolicy($policy);

$policy = new \OCP\AppFramework\Http\ContentSecurityPolicy(false);
$policy->addAllowedFrameDomain('banana.com');
$manager->addDefaultPolicy($policy);
```

If you now open the files app the policy should be:

```
Content-Security-Policy:default-src 'none';script-src yolo.com 'self' 'unsafe-eval';style-src 'self' 'unsafe-inline';img-src 'self' data: blob:;font-src yolo.com 'self';connect-src 'self';media-src 'self';frame-src asdf banana.com 'self'
```

1 files changed, 66 insertions, 0 deletions

diff --git a/tests/lib/security/csp/ContentSecurityPolicyManagerTest.php b/tests/lib/security/csp/ContentSecurityPolicyManagerTest.php
new file mode 100644
index 00000000000..975c35d3780
--- /dev/null
+++ b/tests/lib/security/csp/ContentSecurityPolicyManagerTest.php
@@ -0,0 +1,66 @@
+<?php
+/**
+ * @author Lukas Reschke <lukas@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+use OC\Security\CSP\ContentSecurityPolicyManager;
+
+class ContentSecurityPolicyManagerTest extends \Test\TestCase {
+	/** @var ContentSecurityPolicyManager */
+	private $contentSecurityPolicyManager;
+
+	public function setUp() {
+		parent::setUp();
+		$this->contentSecurityPolicyManager = new ContentSecurityPolicyManager();
+	}
+
+	public function testAddDefaultPolicy() {
+		$this->contentSecurityPolicyManager->addDefaultPolicy(new \OCP\AppFramework\Http\ContentSecurityPolicy());
+	}
+
+	public function testGetDefaultPolicyWithPolicies() {
+		$policy = new \OCP\AppFramework\Http\ContentSecurityPolicy();
+		$policy->addAllowedFontDomain('mydomain.com');
+		$policy->addAllowedImageDomain('anotherdomain.de');
+		$this->contentSecurityPolicyManager->addDefaultPolicy($policy);
+		$policy = new \OCP\AppFramework\Http\ContentSecurityPolicy();
+		$policy->addAllowedFontDomain('example.com');
+		$policy->addAllowedImageDomain('example.org');
+		$policy->allowInlineScript(true);
+		$this->contentSecurityPolicyManager->addDefaultPolicy($policy);
+		$policy = new \OCP\AppFramework\Http\EmptyContentSecurityPolicy();
+		$policy->addAllowedChildSrcDomain('childdomain');
+		$policy->addAllowedFontDomain('anotherFontDomain');
+		$this->contentSecurityPolicyManager->addDefaultPolicy($policy);
+
+		$expected = new \OC\Security\CSP\ContentSecurityPolicy();
+		$expected->allowInlineScript(true);
+		$expected->addAllowedFontDomain('mydomain.com');
+		$expected->addAllowedFontDomain('example.com');
+		$expected->addAllowedFontDomain('anotherFontDomain');
+		$expected->addAllowedImageDomain('anotherdomain.de');
+		$expected->addAllowedImageDomain('example.org');
+		$expected->addAllowedChildSrcDomain('childdomain');
+		$expectedStringPolicy = 'default-src \'none\';script-src \'self\' \'unsafe-inline\' \'unsafe-eval\';style-src \'self\' \'unsafe-inline\';img-src \'self\' data: blob: anotherdomain.de example.org;font-src \'self\' mydomain.com example.com anotherFontDomain;connect-src \'self\';media-src \'self\';child-src childdomain';
+
+		$this->assertEquals($expected, $this->contentSecurityPolicyManager->getDefaultPolicy());
+		$this->assertSame($expectedStringPolicy, $this->contentSecurityPolicyManager->getDefaultPolicy()->buildPolicy());
+	}
+
+}