1// Copyright 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef REMOTING_PROTOCOL_THIRD_PARTY_AUTHENTICATOR_BASE_H_
6#define REMOTING_PROTOCOL_THIRD_PARTY_AUTHENTICATOR_BASE_H_
7
8#include <string>
9
10#include "base/callback.h"
11#include "base/memory/scoped_ptr.h"
12#include "remoting/protocol/authenticator.h"
13#include "third_party/libjingle/source/talk/xmllite/qname.h"
14
15namespace buzz {
16
17class XmlElement;
18
19}  // namespace buzz
20
21namespace remoting {
22namespace protocol {
23
24// Implements an authentication method that relies on a third party server for
25// authentication of both client and host.
26// When third party authentication is being used, the client must request both a
27// token and a shared secret from a third-party server (which may require the
28// user to authenticate themselves). The client then sends only the token to the
29// host. The host signs the token, then contacts the third-party server to
30// exchange the token for the shared secret. Once both client and host have the
31// shared secret, they use an underlying |V2Authenticator| (SPAKE2) to negotiate
32// an authentication key, which is used to establish the connection.
33class ThirdPartyAuthenticatorBase : public Authenticator {
34 public:
35  virtual ~ThirdPartyAuthenticatorBase();
36
37  // Authenticator interface.
38  virtual State state() const OVERRIDE;
39  virtual RejectionReason rejection_reason() const OVERRIDE;
40  virtual void ProcessMessage(const buzz::XmlElement* message,
41                              const base::Closure& resume_callback) OVERRIDE;
42  virtual scoped_ptr<buzz::XmlElement> GetNextMessage() OVERRIDE;
43  virtual scoped_ptr<ChannelAuthenticator>
44      CreateChannelAuthenticator() const OVERRIDE;
45
46 protected:
47  // XML tag names for third party authentication fields.
48  static const buzz::StaticQName kTokenUrlTag;
49  static const buzz::StaticQName kTokenScopeTag;
50  static const buzz::StaticQName kTokenTag;
51
52  explicit ThirdPartyAuthenticatorBase(State initial_state);
53
54  // Gives the message to the underlying authenticator for processing.
55  void ProcessUnderlyingMessage(
56      const buzz::XmlElement* message,
57      const base::Closure& resume_callback);
58
59  // Processes the token-related elements of the message.
60  virtual void ProcessTokenMessage(
61      const buzz::XmlElement* message,
62      const base::Closure& resume_callback) = 0;
63
64  // Adds the token related XML elements to the message.
65  virtual void AddTokenElements(buzz::XmlElement* message) = 0;
66
67  scoped_ptr<Authenticator> underlying_;
68  State token_state_;
69  RejectionReason rejection_reason_;
70
71 private:
72  DISALLOW_COPY_AND_ASSIGN(ThirdPartyAuthenticatorBase);
73};
74
75}  // namespace protocol
76}  // namespace remoting
77
78#endif  // REMOTING_PROTOCOL_THIRD_PARTY_AUTHENTICATOR_BASE_H_
79