From 8d1eecab490886571475ec082fded4ca949a52c1 Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Fri, 19 Jun 2015 17:10:49 -0700
Subject: [PATCH] Allow "." in filebackend container prefixes

* This character in $wgDBname seems to be common enough.
  The wiki ID is the default container prefix, and if it
  is not accepted, then confusing errors occur that block
  all file uploads. The case of dots is handled now.
* Improved variable naming in resolveStoragePath().

Bug: T46066
Change-Id: I68458a876855894d01e8cf880bd6cfcfdae17bd0
---
 includes/filebackend/FileBackendStore.php | 41 +++++++++++++++++------
 1 file changed, 30 insertions(+), 11 deletions(-)

diff --git a/includes/filebackend/FileBackendStore.php b/includes/filebackend/FileBackendStore.php
index 7d2d83188b..e4b07b85e1 100644
--- a/includes/filebackend/FileBackendStore.php
+++ b/includes/filebackend/FileBackendStore.php
@@ -1364,19 +1364,38 @@ abstract class FileBackendStore extends FileBackend {
 	abstract protected function directoriesAreVirtual();
 
 	/**
-	 * Check if a container name is valid.
+	 * Check if a short container name is valid
+	 *
+	 * This checks for length and illegal characters.
+	 * This may disallow certain characters that can appear
+	 * in the prefix used to make the full container name.
+	 *
+	 * @param string $container
+	 * @return bool
+	 */
+	final protected static function isValidShortContainerName( $container ) {
+		// Suffixes like '.xxx' (hex shard chars) or '.seg' (file segments)
+		// might be used by subclasses. Reserve the dot character for sanity.
+		// The only way dots end up in containers (e.g. resolveStoragePath)
+		// is due to the wikiId container prefix or the above suffixes.
+		return self::isValidContainerName( $container ) && !preg_match( '/[.]/', $container );
+	}
+
+	/**
+	 * Check if a full container name is valid
+	 *
 	 * This checks for length and illegal characters.
+	 * Limiting the characters makes migrations to other stores easier.
 	 *
 	 * @param string $container
 	 * @return bool
 	 */
 	final protected static function isValidContainerName( $container ) {
-		// This accounts for Swift and S3 restrictions while leaving room
-		// for things like '.xxx' (hex shard chars) or '.seg' (segments).
-		// This disallows directory separators or traversal characters.
+		// This accounts for NTFS, Swift, and Ceph restrictions
+		// and disallows directory separators or traversal characters.
 		// Note that matching strings URL encode to the same string;
-		// in Swift, the length restriction is *after* URL encoding.
-		return preg_match( '/^[a-z0-9][a-z0-9-_]{0,199}$/i', $container );
+		// in Swift/Ceph, the length restriction is *after* URL encoding.
+		return (bool)preg_match( '/^[a-z0-9][a-z0-9-_.]{0,199}$/i', $container );
 	}
 
 	/**
@@ -1393,17 +1412,17 @@ abstract class FileBackendStore extends FileBackend {
 	 * @return array (container, path, container suffix) or (null, null, null) if invalid
 	 */
 	final protected function resolveStoragePath( $storagePath ) {
-		list( $backend, $container, $relPath ) = self::splitStoragePath( $storagePath );
+		list( $backend, $shortCont, $relPath ) = self::splitStoragePath( $storagePath );
 		if ( $backend === $this->name ) { // must be for this backend
 			$relPath = self::normalizeContainerPath( $relPath );
-			if ( $relPath !== null ) {
+			if ( $relPath !== null && self::isValidShortContainerName( $shortCont ) ) {
 				// Get shard for the normalized path if this container is sharded
-				$cShard = $this->getContainerShard( $container, $relPath );
+				$cShard = $this->getContainerShard( $shortCont, $relPath );
 				// Validate and sanitize the relative path (backend-specific)
-				$relPath = $this->resolveContainerPath( $container, $relPath );
+				$relPath = $this->resolveContainerPath( $shortCont, $relPath );
 				if ( $relPath !== null ) {
 					// Prepend any wiki ID prefix to the container name
-					$container = $this->fullContainerName( $container );
+					$container = $this->fullContainerName( $shortCont );
 					if ( self::isValidContainerName( $container ) ) {
 						// Validate and sanitize the container name (backend-specific)
 						$container = $this->resolveContainerName( "{$container}{$cShard}" );
-- 
2.20.1