network_time_tracker: add temporary time protocol.

components/client_update_protocol/ecdsa.h

 // Copyright 2016 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 COMPONENTS_CLIENT_UPDATE_PROTOCOL_ECDSA_H_
 #define COMPONENTS_CLIENT_UPDATE_PROTOCOL_ECDSA_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 33 matching lines @@
   // to the URL.
   //
   // This method will store internal state in this instance used by calls to
   // ValidateResponse(); if you need to have multiple pings in flight,
   // initialize a separate CUP-ECDSA instance for each one.
   void SignRequest(const base::StringPiece& request_body,
                    std::string* query_params);
 
   // Validates a response given to a ping previously signed with
   // SignRequest(). |response_body| contains the body of the response in
-  // UTF-8. |server_proof| contains the ECDSA signature and observed request
-  // hash, which is passed in the ETag HTTP header. Returns true if the response
-  // is valid and the observed request hash matches the sent hash.  This method
-  // uses internal state that is set by a prior SignRequest() call.
+  // UTF-8. |signature| contains the ECDSA signature and observed request
+  // hash. Returns true if the response is valid and the observed request hash
+  // matches the sent hash.  This method uses internal state that is set by a
+  // prior SignRequest() call.
   bool ValidateResponse(const base::StringPiece& response_body,
-                        const base::StringPiece& server_etag);
+                        const base::StringPiece& signature);
+
+  // Sets the key and nonce that were used to generate a signature that is baked
+  // into a unit test.
+  void OverrideNonceForTesting(int key_version, uint32_t nonce);
 
  private:
-  friend class CupEcdsaTest;
-
   Ecdsa(int key_version, const base::StringPiece& public_key);
 
   // The server keeps multiple signing keys; a version must be sent so that
   // the correct signing key is used to sign the assembled message.
   const int pub_key_version_;
 
   // The ECDSA public key to use for verifying response signatures.
   const std::vector<uint8_t> public_key_;
 
   // The SHA-256 hash of the XML request.  This is modified on each call to
   // SignRequest(), and checked by ValidateResponse().
   std::vector<uint8_t> request_hash_;
 
   // The query string containing key version and nonce in UTF-8 form.  This is
   // modified on each call to SignRequest(), and checked by ValidateResponse().
   std::string request_query_cup2key_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Ecdsa);
 };
 
 }  // namespace client_update_protocol
 
 #endif  // COMPONENTS_CLIENT_UPDATE_PROTOCOL_ECDSA_H_