1. Create a new sandbox type which allows access to Unix sockets in the Mac...

chrome/browser/nacl-loader.sb

+;;
+;; Copyright (c) 2009 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.
+;;
+; This is the Sandbox configuration file used for safeguarding the user's
+; untrusted code within Native Client.
+;
+(version 1)
+(deny default)
+; Support for programmatically enabling verbose debugging.
+;ENABLE_LOGGING (debug deny)
+
+; Allow sending signals to self - http://crbug.com/20370
+(allow signal (target self))
+
+; Needed for full-page-zoomed controls - http://crbug.com/11325
+(allow sysctl-read)
+
+; Each line is marked with the System version that needs it.
+; This profile is tested with the following system versions:
+;     10.5.6, 10.6
+
+; Allow following symlinks
+(allow file-read-metadata)  ; 10.5.6
+
+; Needed for IPC on 10.6
+;10.6_ONLY (allow ipc-posix-shm)
+
+; Needed for the Native Client plugin and loader.
+; TODO(msneck): Refactor Native Client to use something other than Unix
+; sockets.
+; See http://code.google.com/p/nativeclient/issues/detail?id=344
+;BEFORE_10.6 (allow network-inbound (from unix-socket))
+;BEFORE_10.6 (allow network-outbound (to unix-socket))
+;10.6_ONLY (allow network-inbound (regex #"^(/private)?/tmp/nacl-"))
+;10.6_ONLY (allow network-outbound (regex #"^(/private)?/tmp/nacl-"))
+;10.6_ONLY (allow network-bind (local ip4))
+;10.6_ONLY (allow file-write* (regex #"^(/private)?/tmp/nacl-"))