Hook up the Push API with GCM's new ability to own encryption keys.

components/gcm_driver/crypto/gcm_encryption_handler.cc

Index: components/gcm_driver/crypto/gcm_encryption_handler.cc
diff --git a/components/gcm_driver/crypto/gcm_encryption_handler.cc b/components/gcm_driver/crypto/gcm_encryption_handler.cc
new file mode 100644
index 0000000000000000000000000000000000000000..ba0fd8c70503a0adf2ab488300b5ab369282e688
--- /dev/null
+++ b/components/gcm_driver/crypto/gcm_encryption_handler.cc
@@ -0,0 +1,61 @@
+// Copyright 2015 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 "components/gcm_driver/crypto/gcm_encryption_handler.h"
+
+#include "base/bind.h"
+#include "components/gcm_driver/crypto/gcm_key_store.h"
+#include "components/gcm_driver/crypto/proto/gcm_encryption_data.pb.h"
+
+namespace gcm {
+
+GCMEncryptionHandler::GCMEncryptionHandler(
+    const base::FilePath& store_path,
+    scoped_refptr<base::SequencedTaskRunner> blocking_task_runner)
+    : key_store_(new GCMKeyStore(store_path, blocking_task_runner)),
+      weak_ptr_factory_(this) {
+}
+
+GCMEncryptionHandler::~GCMEncryptionHandler() {
+}
+
+void GCMEncryptionHandler::GetPublicEncryptionKey(const std::string& app_id,
+                                                  const KeyCallback& callback) {
+  key_store_->GetKeys(
+      app_id, base::Bind(&GCMEncryptionHandler::DidGetPublicEncryptionKey,
+                         weak_ptr_factory_.GetWeakPtr(), app_id, callback));
+}
+
+void GCMEncryptionHandler::DidGetPublicEncryptionKey(
+    const std::string& app_id,
+    const KeyCallback& callback,
+    const KeyPair& pair) {
+  if (!pair.IsInitialized()) {
+    key_store_->CreateKeys(

[jianli, 2015/07/17 20:55:21]

If GCMEncryptionHandler is the only consumer of GCMKeyStore, it seems to be
better to combine GetKey and CreateKey into one to simplify the logic here.

[Peter Beverloo, 2015/07/20 17:55:53]

Agreed. I implemented the distinction because it'd make key rotation a lot
easier. However, since this will impact the tests, I will do so in a separate
CL. (Together with Ryan's post-commit comments.)

+        app_id, base::Bind(&GCMEncryptionHandler::DidCreatePublicEncryptionKey,
+                           weak_ptr_factory_.GetWeakPtr(), callback));
+    return;
+  }
+
+  DCHECK_EQ(KeyPair::ECDH_CURVE_25519, pair.type());

[jianli, 2015/07/17 20:55:21]

nit: include base/logging.h

[Peter Beverloo, 2015/07/20 17:55:53]

Done.

+  const std::string& public_key = pair.public_key();
+
+  callback.Run(std::vector<uint8_t>(public_key.begin(), public_key.end()));

[jianli, 2015/07/17 20:55:21]

Can we avoid the conversion?

[Peter Beverloo, 2015/07/20 17:55:53]

Moved it to PushMessagingServiceImpl (as we're using WebVector/WebArrayBuffer in
Blink) - this allows the GCMDriver and below to use an std::string.

+}
+
+void GCMEncryptionHandler::DidCreatePublicEncryptionKey(
+    const KeyCallback& callback,
+    const KeyPair& pair) {
+  if (!pair.IsInitialized()) {
+    callback.Run(std::vector<uint8_t>());
+    return;
+  }
+
+  DCHECK_EQ(KeyPair::ECDH_CURVE_25519, pair.type());
+  const std::string& public_key = pair.public_key();
+
+  callback.Run(std::vector<uint8_t>(public_key.begin(), public_key.end()));
+}
+
+}  // namespace gcm