remoting/protocol/third_party_host_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_HOST_AUTHENTICATOR_H_
   6 #define REMOTING_PROTOCOL_THIRD_PARTY_HOST_AUTHENTICATOR_H_
   7
   8 #include <string>
   9
  10 #include "base/callback.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "remoting/protocol/third_party_authenticator_base.h"
  13 #include "url/gurl.h"
  14
  15 namespace remoting {
  16
  17 class RsaKeyPair;
  18
  19 namespace protocol {
  20
  21 // Implements the host side of the third party authentication mechanism.
  22 // The host authenticator sends the |token_url| and |scope| obtained from the
  23 // |TokenValidator| to the client, and expects a |token| in response.
  24 // Once that token is received, it calls |TokenValidator| asynchronously to
  25 // validate it, and exchange it for a |shared_secret|. Once the |TokenValidator|
  26 // returns, the host uses the |shared_secret| to create an underlying
  27 // |V2Authenticator|, which is used to establish the encrypted connection.
  28 class ThirdPartyHostAuthenticator : public ThirdPartyAuthenticatorBase {
  29  public:
  30   class TokenValidator {
  31    public:
  32     // Callback passed to |ValidateThirdPartyToken|, and called once the host
  33     // authentication finishes. |shared_secret| should be used by the host to
  34     // create a V2Authenticator. In case of failure, the callback is called with
  35     // an empty |shared_secret|.
  36     typedef base::Callback<void(
  37                 const std::string& shared_secret)> TokenValidatedCallback;
  38
  39     virtual ~TokenValidator() {}
  40
  41     // Validates |token| with the server and exchanges it for a |shared_secret|.
  42     // |token_validated_callback| is called when the host authentication ends,
  43     // in the same thread |ValidateThirdPartyToken| was originally called.
  44     // The request is canceled if this object is destroyed.
  45     virtual void ValidateThirdPartyToken(
  46         const std::string& token,
  47         const TokenValidatedCallback& token_validated_callback) = 0;
  48
  49     // URL sent to the client, to be used by its |TokenFetcher| to get a token.
  50     virtual const GURL& token_url() const = 0;
  51
  52     // Space-separated list of connection attributes the host must send to the
  53     // client, and require the token received in response to match.
  54     virtual const std::string& token_scope() const = 0;
  55   };
  56
  57   class TokenValidatorFactory {
  58    public:
  59     virtual ~TokenValidatorFactory() {}
  60
  61     // Creates a TokenValidator. |local_jid| and |remote_jid| are used to create
  62     // a token scope that is restricted to the current connection's JIDs.
  63     virtual scoped_ptr<TokenValidator> CreateTokenValidator(
  64         const std::string& local_jid,
  65         const std::string& remote_jid) = 0;
  66   };
  67
  68   // Creates a third-party host authenticator. |local_cert| and |key_pair| are
  69   // used by the underlying V2Authenticator to create the SSL channels.
  70   // |token_validator| contains the token parameters to be sent to the client
  71   // and is used to obtain the shared secret.
  72   ThirdPartyHostAuthenticator(const std::string& local_cert,
  73                               scoped_refptr<RsaKeyPair> key_pair,
  74                               scoped_ptr<TokenValidator> token_validator);
  75   virtual ~ThirdPartyHostAuthenticator();
  76
  77  protected:
  78   // ThirdPartyAuthenticator implementation.
  79   virtual void ProcessTokenMessage(
  80       const buzz::XmlElement* message,
  81       const base::Closure& resume_callback) OVERRIDE;
  82   virtual void AddTokenElements(buzz::XmlElement* message) OVERRIDE;
  83
  84  private:
  85   void OnThirdPartyTokenValidated(const buzz::XmlElement* message,
  86                                   const base::Closure& resume_callback,
  87                                   const std::string& shared_secret);
  88
  89   std::string local_cert_;
  90   scoped_refptr<RsaKeyPair> key_pair_;
  91   scoped_ptr<TokenValidator> token_validator_;
  92
  93   DISALLOW_COPY_AND_ASSIGN(ThirdPartyHostAuthenticator);
  94 };
  95
  96 }  // namespace protocol
  97 }  // namespace remoting
  98
  99 #endif  // REMOTING_PROTOCOL_THIRD_PARTY_HOST_AUTHENTICATOR_H_