jschuh@chromium.org | f75a4d1 | 2012-03-17 11:20:46 +0900 | [diff] [blame] | 1 | // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "ipc/ipc_channel.h" |
| 6 | |
| 7 | #include <limits> |
| 8 | |
| 9 | #include "base/atomic_sequence_num.h" |
jschuh@chromium.org | f75a4d1 | 2012-03-17 11:20:46 +0900 | [diff] [blame] | 10 | #include "base/rand_util.h" |
avi@chromium.org | e7eaf39 | 2013-06-11 15:32:18 +0900 | [diff] [blame] | 11 | #include "base/strings/stringprintf.h" |
jschuh@chromium.org | f75a4d1 | 2012-03-17 11:20:46 +0900 | [diff] [blame] | 12 | |
thakis@chromium.org | b78cb8e | 2012-09-24 13:49:10 +0900 | [diff] [blame] | 13 | #if !defined(OS_NACL) |
jschuh@chromium.org | f75a4d1 | 2012-03-17 11:20:46 +0900 | [diff] [blame] | 14 | namespace { |
| 15 | |
| 16 | // Global atomic used to guarantee channel IDs are unique. |
| 17 | base::StaticAtomicSequenceNumber g_last_id; |
| 18 | |
| 19 | } // namespace |
thakis@chromium.org | b78cb8e | 2012-09-24 13:49:10 +0900 | [diff] [blame] | 20 | #endif |
jschuh@chromium.org | f75a4d1 | 2012-03-17 11:20:46 +0900 | [diff] [blame] | 21 | |
| 22 | namespace IPC { |
| 23 | |
| 24 | // static |
| 25 | std::string Channel::GenerateUniqueRandomChannelID() { |
| 26 | // Note: the string must start with the current process id, this is how |
| 27 | // some child processes determine the pid of the parent. |
| 28 | // |
| 29 | // This is composed of a unique incremental identifier, the process ID of |
| 30 | // the creator, an identifier for the child instance, and a strong random |
| 31 | // component. The strong random component prevents other processes from |
| 32 | // hijacking or squatting on predictable channel names. |
| 33 | |
bbudge@chromium.org | b562dcc | 2012-06-16 09:35:01 +0900 | [diff] [blame] | 34 | int process_id = base::GetCurrentProcId(); |
jschuh@chromium.org | f75a4d1 | 2012-03-17 11:20:46 +0900 | [diff] [blame] | 35 | return base::StringPrintf("%d.%u.%d", |
bbudge@chromium.org | aa4d16a | 2012-04-24 06:18:19 +0900 | [diff] [blame] | 36 | process_id, |
jschuh@chromium.org | f75a4d1 | 2012-03-17 11:20:46 +0900 | [diff] [blame] | 37 | g_last_id.GetNext(), |
| 38 | base::RandInt(0, std::numeric_limits<int32>::max())); |
jschuh@chromium.org | f75a4d1 | 2012-03-17 11:20:46 +0900 | [diff] [blame] | 39 | } |
| 40 | |
| 41 | } // namespace IPC |
| 42 | |