[Sync] Add support for performing a GetKey on startup.

sync/util/cryptographer.cc

 // 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 "sync/util/cryptographer.h"
 
 #include <algorithm>
 
 #include "base/base64.h"
 #include "base/logging.h"
 #include "sync/util/encryptor.h"
 
 namespace syncer {
 
 const char kNigoriTag[] = "google_chrome_nigori";
 
 // We name a particular Nigori instance (ie. a triplet consisting of a hostname,
 // a username, and a password) by calling Permute on this string. Since the
 // output of Permute is always the same for a given triplet, clients will always
 // assign the same name to a particular triplet.
 const char kNigoriKeyName[] = "nigori-key";
 
 Cryptographer::Observer::~Observer() {}
 
 Cryptographer::Cryptographer(Encryptor* encryptor)
     : encryptor_(encryptor),
       default_nigori_(NULL),
+      keystore_nigori_(NULL),
       encrypted_types_(SensitiveTypes()),
       encrypt_everything_(false) {
   DCHECK(encryptor);
 }
 
 Cryptographer::~Cryptographer() {}
 
 void Cryptographer::AddObserver(Observer* observer) {
   observers_.AddObserver(observer);
 }
@@ skipping 263 matching lines @@
       }
       return Cryptographer::SUCCESS;
     } else {
       SetPendingKeys(nigori.encrypted());
       return Cryptographer::NEEDS_PASSPHRASE;
     }
   }
   return Cryptographer::SUCCESS;
 }
 
+bool Cryptographer::SetKeystoreKey(const std::string& keystore_key) {
+  if (keystore_key.empty())
+    return false;
+  KeyParams params = {"localhost", "dummy", keystore_key};
+
+  // AddKey updates the default nigori, so we save the current default and
+  // make sure the keystore_nigori_ gets updated instead.
+  NigoriMap::value_type* old_default = default_nigori_;
+  if (AddKey(params)) {
+    keystore_nigori_ = default_nigori_;
+    default_nigori_ = old_default;
+    return true;
+  }
+  return false;
+}
+
+bool Cryptographer::HasKeystoreKey() {
+  return keystore_nigori_ != NULL;
+}
+
 // Static
 syncer::ModelTypeSet Cryptographer::SensitiveTypes() {
   // Both of these have their own encryption schemes, but we include them
   // anyways.
   syncer::ModelTypeSet types;
   types.Put(syncer::PASSWORDS);
   types.Put(syncer::NIGORI);
   return types;
 }
 
@@ skipping 123 matching lines @@
                                     key.mac_key())) {
         NOTREACHED();
         continue;
       }
       nigoris_[key.name()] = make_linked_ptr(new_nigori.release());
     }
   }
 }
 
 }  // namespace syncer