Verify the child process with a secret hello

BUG=117627
TEST=IPCSyncChannelTest.Verified

Review URL: http://codereview.chromium.org/9692035

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@127327 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 40 insertions, 0 deletions

diff --git a/ipc/ipc_channel.cc b/ipc/ipc_channel.cc
new file mode 100644
index 0000000..5973f72
--- /dev/null
+++ b/ipc/ipc_channel.cc
@@ -0,0 +1,40 @@
+// Copyright (c) 2012 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.
+
+#include "ipc/ipc_channel.h"
+
+#include <limits>
+
+#include "base/atomic_sequence_num.h"
+#include "base/process_util.h"
+#include "base/rand_util.h"
+#include "base/stringprintf.h"
+
+namespace {
+
+// Global atomic used to guarantee channel IDs are unique.
+base::StaticAtomicSequenceNumber g_last_id;
+
+}  // namespace
+
+namespace IPC {
+
+// static
+std::string Channel::GenerateUniqueRandomChannelID() {
+  // Note: the string must start with the current process id, this is how
+  // some child processes determine the pid of the parent.
+  //
+  // This is composed of a unique incremental identifier, the process ID of
+  // the creator, an identifier for the child instance, and a strong random
+  // component. The strong random component prevents other processes from
+  // hijacking or squatting on predictable channel names.
+
+  return base::StringPrintf("%d.%u.%d",
+      base::GetCurrentProcId(),
+      g_last_id.GetNext(),
+      base::RandInt(0, std::numeric_limits<int32>::max()));
+}
+
+}  // namespace IPC
+