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

chrome/renderer/renderer.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.
 ;;
 (version 1)
 (deny default)
 ; Support for programmatically enabling verbose debugging.
 ;ENABLE_LOGGING (debug deny)
 
@@ skipping 14 matching lines @@
 (allow file-read-data (regex #"^/System/Library/Frameworks($|/)"))  ; 10.5.6
 (allow file-read-data (regex #"^/System/Library/PrivateFrameworks($|/)"))  ; 10.5.6
 (allow file-read-data (regex #"^/System/Library/CoreServices($|/)"))  ; 10.5.6
 
 ; Needed for Fonts.
 (allow file-read-data (regex #"^/System/Library/Fonts($|/)"))  ; 10.5.6
 ;10.6_ONLY (allow file-read-data (regex #"^/Library/Fonts($|/)"))  ; 10.6
 (allow mach-lookup (global-name "com.apple.FontObjectsServer"))  ; 10.5.6
 ;10.6_ONLY (allow mach-lookup (global-name "com.apple.FontServer"))  ; 10.6
 
-; USER_HOMEDIR is substitued at runtime - http://crbug.com/11269 
+; USER_HOMEDIR is substitued at runtime - http://crbug.com/11269
 ;10.6_ONLY (allow file-read-data (subpath "USER_HOMEDIR/Library/Fonts"))  ; 10.6
 
 ; Needed for IPC on 10.6
 ;10.6_ONLY (allow ipc-posix-shm)
+
+; Needed for the Native Client plugin and loader. These lines are enabled
+; if and only if --internal-nacl (or --enable-nacl) are used (and they
+; are off by default).
+; TODO(msneck): Refactor Native Client to use something other than Unix
+; sockets. Then change or remove the code in chrome/common/sandbox_mac.mm
+; which deals with the ";NACL" prefix.
+; See http://code.google.com/p/nativeclient/issues/detail?id=344
+;NACL;BEFORE_10.6 (allow network-inbound (from unix-socket))
+;NACL;BEFORE_10.6 (allow network-outbound (to unix-socket))
+;NACL;10.6_ONLY (allow network-inbound (regex #"^(/private)?/tmp/nacl-"))
+;NACL;10.6_ONLY (allow network-outbound (regex #"^(/private)?/tmp/nacl-"))
+;NACL;10.6_ONLY (allow network-bind (local ip4))
+;NACL;10.6_ONLY (allow file-write* (regex #"^(/private)?/tmp/nacl-"))