remoting/protocol/third_party_client_authenticator.h

   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_CLIENT_AUTHENTICATOR_H_
   6 #define REMOTING_PROTOCOL_THIRD_PARTY_CLIENT_AUTHENTICATOR_H_
   7
   8 #include <string>
   9
  10 #include "base/callback.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/memory/weak_ptr.h"
  13 #include "remoting/protocol/third_party_authenticator_base.h"
  14 #include "url/gurl.h"
  15
  16 class GURL;
  17
  18 namespace remoting {
  19 namespace protocol {
  20
  21 // Implements the client side of the third party authentication mechanism.
  22 // The client authenticator expects a |token_url| and |scope| in the first
  23 // message from the host, then calls the |TokenFetcher| asynchronously to
  24 // request a |token| and |shared_secret| from that url. If the server requires
  25 // interactive authentication, the |TokenFetcher| implementation will show the
  26 // appropriate UI. Once the |TokenFetcher| returns, the client sends the |token|
  27 // to the host, and uses the |shared_secret| to create an underlying
  28 // |V2Authenticator|, which is used to establish the encrypted connection.
  29 class ThirdPartyClientAuthenticator : public ThirdPartyAuthenticatorBase {
  30  public:
  31   class TokenFetcher {
  32    public:
  33     // Callback passed to |FetchThirdPartyToken|, and called once the client
  34     // authentication finishes. |token| is an opaque string that should be sent
  35     // directly to the host. |shared_secret| should be used by the client to
  36     // create a V2Authenticator. In case of failure, the callback is called with
  37     // an empty |token| and |shared_secret|.
  38     typedef base::Callback<void(
  39         const std::string& token,
  40         const std::string& shared_secret)> TokenFetchedCallback;
  41
  42     virtual ~TokenFetcher() {}
  43
  44     // Fetches a third party token from |token_url|. |host_public_key| is sent
  45     // to the server so it can later authenticate the host. |scope| is a string
  46     // with a space-separated list of attributes for this connection (e.g.
  47     // "hostjid:abc@example.com/123 clientjid:def@example.org/456".
  48     // |token_fetched_callback| is called when the client authentication ends,
  49     // in the same thread |FetchThirdPartyToken| was originally called.
  50     // The request is canceled if the TokenFetcher is destroyed.
  51     virtual void FetchThirdPartyToken(
  52         const GURL& token_url,
  53         const std::string& scope,
  54         const TokenFetchedCallback& token_fetched_callback) = 0;
  55   };
  56
  57   // Creates a third-party client authenticator for the host with the given
  58   // |host_public_key|. |token_fetcher| is used to get the authentication token.
  59   explicit ThirdPartyClientAuthenticator(
  60       scoped_ptr<TokenFetcher> token_fetcher);
  61   ~ThirdPartyClientAuthenticator() override;
  62
  63  protected:
  64   // ThirdPartyAuthenticator implementation.
  65   void ProcessTokenMessage(const buzz::XmlElement* message,
  66                            const base::Closure& resume_callback) override;
  67   void AddTokenElements(buzz::XmlElement* message) override;
  68
  69  private:
  70   void OnThirdPartyTokenFetched(const base::Closure& resume_callback,
  71                                 const std::string& third_party_token,
  72                                 const std::string& shared_secret);
  73
  74   std::string token_;
  75   scoped_ptr<TokenFetcher> token_fetcher_;
  76
  77   DISALLOW_COPY_AND_ASSIGN(ThirdPartyClientAuthenticator);
  78 };
  79
  80
  81 }  // namespace protocol
  82 }  // namespace remoting
  83
  84 #endif  // REMOTING_PROTOCOL_THIRD_PARTY_CLIENT_AUTHENTICATOR_H_