Implement ChildProcessSecurityPolicy::HasPermissionsForFileSystemFile()

In content/ layer:
- Add CPSP::HasPermissionsForFileSystemFile() for central
  FileSystem permission check.
- Replace all permission check code for FileSystem files with the
  newly added CPSP method

In webkit/browser/fileapi layer:
- Each MountPointProvider's GetPermissionPolicy() is replaced with a
  central static FileSystemContext::GetPermissionPolicy() method.
  Now the permission policy is statically defined for each type and
  used by CPSP.  Some FS-specific security checks are moved into
  each FS's private implementation.
- For SandboxMountPointProvider: moved some API-specific validity
  check code into a private IsAcessValid() method.
- For CrosMountPointProvider:  IsAccessAllowed() method is still called
  every time when a new FileSystemOperation is created, but doesn't
  participate the CPSP's permission check.

BUG=174550
TEST=ChildProcessSecurityPolicyTest::FileSystemFilePermissions
R=aedla@chromium.org, darin@chromium.org, tbarzic@chromium.org, tsepez@chromium.org

Review URL: https://codereview.chromium.org/12310099

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@209418 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 46 insertions, 0 deletions

diff --git a/webkit/browser/fileapi/file_system_context.cc b/webkit/browser/fileapi/file_system_context.cc
index 79a4945..97f4205 100644
--- a/webkit/browser/fileapi/file_system_context.cc
+++ b/webkit/browser/fileapi/file_system_context.cc
@@ -11,6 +11,7 @@
 #include "webkit/browser/blob/file_stream_reader.h"
 #include "webkit/browser/fileapi/copy_or_move_file_validator.h"
 #include "webkit/browser/fileapi/external_mount_points.h"
+#include "webkit/browser/fileapi/file_permission_policy.h"
 #include "webkit/browser/fileapi/file_stream_writer.h"
 #include "webkit/browser/fileapi/file_system_file_util.h"
 #include "webkit/browser/fileapi/file_system_operation.h"
@@ -53,6 +54,51 @@ void DidOpenFileSystem(
 
 }  // namespace
 
+// static
+int FileSystemContext::GetPermissionPolicy(FileSystemType type) {
+  switch (type) {
+    case kFileSystemTypeTemporary:
+    case kFileSystemTypePersistent:
+    case kFileSystemTypeSyncable:
+      return FILE_PERMISSION_SANDBOX;
+
+    case kFileSystemTypeDrive:
+    case kFileSystemTypeNativeForPlatformApp:
+    case kFileSystemTypeNativeLocal:
+      return FILE_PERMISSION_USE_FILE_PERMISSION;
+
+    case kFileSystemTypeRestrictedNativeLocal:
+      return FILE_PERMISSION_READ_ONLY |
+             FILE_PERMISSION_USE_FILE_PERMISSION;
+
+    // Following types are only accessed via IsolatedFileSystem, and
+    // don't have their own permission policies.
+    case kFileSystemTypeDeviceMedia:
+    case kFileSystemTypeDragged:
+    case kFileSystemTypeForTransientFile:
+    case kFileSystemTypeItunes:
+    case kFileSystemTypeNativeMedia:
+    case kFileSystemTypePicasa:
+      return FILE_PERMISSION_ALWAYS_DENY;
+
+    // Following types only appear as mount_type, and will not be
+    // queried for their permission policies.
+    case kFileSystemTypeIsolated:
+    case kFileSystemTypeExternal:
+      return FILE_PERMISSION_ALWAYS_DENY;
+
+    // Following types should not be used to access files by FileAPI clients.
+    case kFileSystemTypeTest:
+    case kFileSystemTypeSyncableForInternalSync:
+    case kFileSystemInternalTypeEnumEnd:
+    case kFileSystemInternalTypeEnumStart:
+    case kFileSystemTypeUnknown:
+      return FILE_PERMISSION_ALWAYS_DENY;
+  }
+  NOTREACHED();
+  return FILE_PERMISSION_ALWAYS_DENY;
+}
+
 FileSystemContext::FileSystemContext(
     scoped_ptr<FileSystemTaskRunners> task_runners,
     ExternalMountPoints* external_mount_points,