core: Move default bridges to whitelist.default.txt

Default bridges are currently statically defined in index.php, which
is not the right place if we want to keep responsibilities separated.

This commit introduces a new file whitelist.default.txt that holds
the default bridges and which is loaded automatically, if whitelist.txt
doesn't exist.

Due to this it is also no longer necessary to have write permission
for the root directory.

References #1001

index.php

@@ -29,27 +29,8 @@ define('USER_AGENT',
 
 ini_set('user_agent', USER_AGENT);
 
-// default whitelist
-$whitelist_default = array(
-	'BandcampBridge',
-	'CryptomeBridge',
-	'DansTonChatBridge',
-	'DuckDuckGoBridge',
-	'FacebookBridge',
-	'FlickrBridge',
-	'GoogleSearchBridge',
-	'IdenticaBridge',
-	'InstagramBridge',
-	'OpenClassroomsBridge',
-	'PinterestBridge',
-	'ScmbBridge',
-	'TwitterBridge',
-	'WikipediaBridge',
-	'YoutubeBridge');
-
 try {
 
-	Bridge::setWhitelist($whitelist_default);
 	$actionFac = new \ActionFactory();
 	$actionFac->setWorkingDir(PATH_LIB_ACTIONS);
 

lib/Bridge.php

@@ -192,7 +192,8 @@ class Bridge {
 	/**
 	 * Returns the whitelist.
 	 *
-	 * On first call this function reads the whitelist from {@see WHITELIST}.
+	 * On first call this function reads the whitelist from {@see WHITELIST} if
+	 * the file exists, {@see WHITELIST_DEFAULT} otherwise.
 	 * * Each line in the file specifies one bridge on the whitelist.
 	 * * An empty file disables all bridges.
 	 * * If the file only only contains `*`, all bridges are whitelisted.
@@ -210,19 +211,21 @@ class Bridge {
 
 		if($firstCall) {
 
-			// Create initial whitelist or load from disk
+			if(file_exists(WHITELIST)) {
-			if (!file_exists(WHITELIST) && !empty(self::$whitelist)) {
-				file_put_contents(WHITELIST, implode("\n", self::$whitelist));
-			} elseif(file_exists(WHITELIST)) {
-
 				$contents = trim(file_get_contents(WHITELIST));
+			} elseif(file_exists(WHITELIST_DEFAULT)) {
+				$contents = trim(file_get_contents(WHITELIST_DEFAULT));
+			} else {
+				$contents = '';
+			}
 
 			if($contents === '*') { // Whitelist all bridges
 				self::$whitelist = self::getBridgeNames();
 			} else {
-					self::$whitelist = array_map('self::sanitizeBridgeName', explode("\n", $contents));
+				//self::$whitelist = array_map('self::sanitizeBridgeName', explode("\n", $contents));
+				foreach(explode("\n", $contents) as $bridgeName) {
+					self::$whitelist[] = self::sanitizeBridgeName($bridgeName);
 				}
-
 			}
 
 		}

lib/Configuration.php

@@ -106,10 +106,6 @@ final class Configuration {
 		if(!is_writable(PATH_CACHE))
 			die('RSS-Bridge does not have write permissions for ' . PATH_CACHE . '!');
 
-		// Check whitelist file permissions
-		if(!file_exists(WHITELIST) && !is_writable(dirname(WHITELIST)))
-			die('RSS-Bridge does not have write permissions for ' . WHITELIST . '!');
-
 	}
 
 	/**

lib/rssbridge.php

@@ -38,6 +38,9 @@ define('PATH_CACHE', __DIR__ . '/../cache/');
 /** Path to the whitelist file */
 define('WHITELIST', __DIR__ . '/../whitelist.txt');
 
+/** Path to the default whitelist file */
+define('WHITELIST_DEFAULT', __DIR__ . '/../whitelist.default.txt');
+
 /** URL to the RSS-Bridge repository */
 define('REPOSITORY', 'https://github.com/RSS-Bridge/rss-bridge/');
 

whitelist.default.txt

@@ -0,0 +1,15 @@
+Bandcamp
+Cryptome
+DansTonChat
+DuckDuckGo
+Facebook
+Flickr
+GoogleSearch
+Identica
+Instagram
+OpenClassrooms
+Pinterest
+Scmb
+Twitter
+Wikipedia
+Youtube