Convert utility process Safe Browsing ZIP/DMG Analyzer IPC to mojo

chrome/common/safe_archive_analyzer.mojom

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Safe archive file analyzer provided by the utility process and exposed
+// by mojo policy control to the chrome browser process when build flag
+// FULL_SAFE_BROWSING is enabled.
+
+module chrome.mojom;
+
+import "mojo/common/file.mojom";
+
+interface SafeArchiveAnalyzer {
+  // Build flag FULL_SAFE_BROWSING: Analyze the |zip_file| for malicious
+  // download protection, given a |temporary_file| used to extract files

[tibell, 2017/03/08 23:55:47]

The |temporary_file| confuses me. What is it for? I'd expect a temporary
directory to unpack the zip file into, not a file.

[Noel Gordon, 2017/03/09 02:24:59]

Given the chrome_utility_messages.h API, they only required a temporary _file_,
not a directory, so I assume (/me not looking at their code) that they extract
files from the extension zip one after the other: extract file, check file, move
on to the next file.

Shame that a temporary file needs to be on this API, but since this code runs in
a sandboxed utility process (not allowed to open files), the API has to provide
the temporary file they need to get the job done.

+  // from the |zip_file| archive.
+  AnalyzeZipFile(mojo.common.mojom.File zip_file,
+                 mojo.common.mojom.File temporary_file)
+      => (SafeArchiveAnalyzerResults results);
+
+  // Build flag FULL_SAFE_BROWSING, on OS_MACOSX: Analyze the |dmg_file|
+  // for malicious download protection.
+  AnalyzeDmgFile(mojo.common.mojom.File dmg_file)
+      => (SafeArchiveAnalyzerResults results);
+};
+
+[Native]
+struct SafeArchiveAnalyzerResults;