Pull cacheinvalidations code directory into chromium repo.

third_party/cacheinvalidation/src/google/cacheinvalidation/impl/persistence-utils.cc

Index: third_party/cacheinvalidation/src/google/cacheinvalidation/impl/persistence-utils.cc
diff --git a/third_party/cacheinvalidation/src/google/cacheinvalidation/impl/persistence-utils.cc b/third_party/cacheinvalidation/src/google/cacheinvalidation/impl/persistence-utils.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e9c1b3d962fb544758515a3800003d45f52682b7
--- /dev/null
+++ b/third_party/cacheinvalidation/src/google/cacheinvalidation/impl/persistence-utils.cc
@@ -0,0 +1,61 @@
+// Copyright 2012 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Utility methods for handling the Ticl persistent state.
+
+#include "google/cacheinvalidation/impl/persistence-utils.h"
+
+namespace invalidation {
+
+void PersistenceUtils::SerializeState(
+    PersistentTiclState state, DigestFunction* digest_fn, string* result) {
+  string mac = GenerateMac(state, digest_fn);
+  PersistentStateBlob blob;
+  blob.mutable_ticl_state()->CopyFrom(state);
+  blob.set_authentication_code(mac);
+  blob.SerializeToString(result);
+}
+
+bool PersistenceUtils::DeserializeState(
+    Logger* logger, const string& state_blob_bytes, DigestFunction* digest_fn,
+    PersistentTiclState* ticl_state) {
+  PersistentStateBlob state_blob;
+  state_blob.ParseFromString(state_blob_bytes);
+  if (!state_blob.IsInitialized()) {
+    TLOG(logger, WARNING, "could not parse state blob from %s",
+         state_blob_bytes.c_str());
+    return false;
+  }
+
+  // Check the mac in the envelope against the recomputed mac from the state.
+  ticl_state->CopyFrom(state_blob.ticl_state());
+  const string& mac = GenerateMac(*ticl_state, digest_fn);
+  if (mac != state_blob.authentication_code()) {
+    TLOG(logger, WARNING, "Ticl state failed MAC check: computed %s vs %s",
+         mac.c_str(), state_blob.authentication_code().c_str());
+    return false;
+  }
+  return true;
+}
+
+string PersistenceUtils::GenerateMac(
+    const PersistentTiclState& state, DigestFunction* digest_fn) {
+  string serialized;
+  state.SerializeToString(&serialized);
+  digest_fn->Reset();
+  digest_fn->Update(serialized);
+  return digest_fn->GetDigest();
+}
+
+}  // namespace invalidation