Stub in more IPC attachment brokering functionality.

This CL fills in most of the logic for sending a Windows HANDLE from a
non-broker process to the broker process. This consists of several small
changes:

- Create the new IPC messages AttachmentBrokerMsg_WinHandleHasBeenBrokered and
AttachmentBrokerMsg_RequestBrokerageOfWinHandle.
- Add a sender_ member variable to AttachmentBrokerWin.
- Define the wire format for HandleAttachmentWin.
- Add logic to ChannelWin to send
AttachmentBrokerMsg_RequestBrokerageOfWinHandle for each HANDLE attachment.

BUG=466437

Review URL: https://codereview.chromium.org/1188923003

Cr-Commit-Position: refs/heads/master@{#337689}

1 files changed, 22 insertions, 0 deletions

diff --git a/ipc/ipc_message_utils.cc b/ipc/ipc_message_utils.cc
index b6b9792..dbb2572 100644
--- a/ipc/ipc_message_utils.cc
+++ b/ipc/ipc_message_utils.cc
@@ -449,6 +449,28 @@ void ParamTraits<std::vector<bool> >::Log(const param_type& p, std::string* l) {
   }
 }
 
+void ParamTraits<BrokerableAttachment::AttachmentId>::Write(
+    Message* m,
+    const param_type& p) {
+  m->WriteBytes(p.nonce, BrokerableAttachment::kNonceSize);
+}
+
+bool ParamTraits<BrokerableAttachment::AttachmentId>::Read(
+    const Message* m,
+    base::PickleIterator* iter,
+    param_type* r) {
+  const char* data;
+  if (!iter->ReadBytes(&data, BrokerableAttachment::kNonceSize))
+    return false;
+  memcpy(r->nonce, data, BrokerableAttachment::kNonceSize);
+  return true;
+}
+
+void ParamTraits<BrokerableAttachment::AttachmentId>::Log(const param_type& p,
+                                                          std::string* l) {
+  l->append(base::HexEncode(p.nonce, BrokerableAttachment::kNonceSize));
+}
+
 void ParamTraits<base::DictionaryValue>::Write(Message* m,
                                                const param_type& p) {
   WriteValue(m, &p, 0);