Refactor TokenValidatorImpl into a base class + implementation.

remoting/protocol/token_validator.h

+// Copyright 2014 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.
+
+#ifndef REMOTING_PROTOCOL_TOKEN_VALIDATOR_H_
+#define REMOTING_PROTOCOL_TOKEN_VALIDATOR_H_
+
+#include <string>
+
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
+#include "url/gurl.h"
+
+namespace remoting {
+
+class RsaKeyPair;
+
+namespace protocol {
+
+// The |TokenValidator| encapsulates the parameters to be sent to the client
+// to obtain a token, and the method to validate that token and obtain the
+// shared secret for the connection.
+class TokenValidator {
+ public:
+  // Callback passed to |ValidateThirdPartyToken|, and called once the host
+  // authentication finishes. |shared_secret| should be used by the host to
+  // create a V2Authenticator. In case of failure, the callback is called with
+  // an empty |shared_secret|.
+  typedef base::Callback<void(
+      const std::string& shared_secret)> TokenValidatedCallback;
+
+  virtual ~TokenValidator() {}
+
+  // Validates |token| with the server and exchanges it for a |shared_secret|.
+  // |token_validated_callback| is called when the host authentication ends,
+  // in the same thread |ValidateThirdPartyToken| was originally called.
+  // The request is canceled if this object is destroyed.
+  virtual void ValidateThirdPartyToken(
+      const std::string& token,
+      const TokenValidatedCallback& token_validated_callback) = 0;
+
+  // URL sent to the client, to be used by its |TokenFetcher| to get a token.
+  virtual const GURL& token_url() const = 0;
+
+  // Space-separated list of connection attributes the host must send to the
+  // client, and require the token received in response to match.
+  virtual const std::string& token_scope() const = 0;
+};
+
+// Factory for |TokenValidator|.
+class TokenValidatorFactory {
+ public:
+  virtual ~TokenValidatorFactory() {}
+
+  // Creates a TokenValidator. |local_jid| and |remote_jid| are used to create
+  // a token scope that is restricted to the current connection's JIDs.
+  virtual scoped_ptr<TokenValidator> CreateTokenValidator(
+      const std::string& local_jid,
+      const std::string& remote_jid) = 0;
+};
+
+}  // namespace protocol
+}  // namespace remoting
+
+#endif  // REMOTING_PROTOCOL_TOKEN_VALIDATOR_H_