Certificate Transparency: Fetching consistency proofs.

components/certificate_transparency/log_proof_fetcher.h

Index: components/certificate_transparency/log_proof_fetcher.h
diff --git a/components/certificate_transparency/log_proof_fetcher.h b/components/certificate_transparency/log_proof_fetcher.h
index ba952e365d6f77177184a9c70648e2b9f6ef6b09..0a062e1eb29a4b83937c871eea971b694e5c8812 100644
--- a/components/certificate_transparency/log_proof_fetcher.h
+++ b/components/certificate_transparency/log_proof_fetcher.h
@@ -53,6 +53,14 @@ class LogProofFetcher : public net::URLRequest::Delegate {
   using FetchFailedCallback = base::Callback<
       void(const std::string& log_id, int net_error, int http_response_code)>;
 
+  // Callback for successful retrieval of consistency proofs between two
+  // STHs. Called with the log_id of the log the consistency belongs to (as
+  // supplied by the caller to FetchConsistencyProof) and the vector of
+  // proof nodes.
+  using ConsistencyProofFetchedCallback =
+      base::Callback<void(const std::string& log_id,
+                          const std::vector<std::string>& consistency_proof)>;
+
   explicit LogProofFetcher(net::URLRequestContext* request_context);
   ~LogProofFetcher() override;
 
@@ -73,6 +81,20 @@ class LogProofFetcher : public net::URLRequest::Delegate {
       const SignedTreeHeadFetchedCallback& fetched_callback,
       const FetchFailedCallback& failed_callback);
 
+  // Fetch a consistency proof between the Merkle trees identified by
+  // |old_tree_size| and |new_tree_size| of the log identified by |log_id|
+  // from |base_log_url|.
+  //
+  // See the documentation of FetchSignedTreeHead regarding request destruction
+  // and multiple requests to the same log.
+  void FetchConsistencyProof(
+      const GURL& base_log_url,
+      const std::string& log_id,
+      size_t old_tree_size,
+      size_t new_tree_size,
+      const ConsistencyProofFetchedCallback& fetched_callback,
+      const FetchFailedCallback& failed_callback);
+
   // net::URLRequest::Delegate
   void OnResponseStarted(net::URLRequest* request) override;
   void OnReadCompleted(net::URLRequest* request, int bytes_read) override;
@@ -107,11 +129,24 @@ class LogProofFetcher : public net::URLRequest::Delegate {
                              scoped_ptr<base::Value> parsed_json);
   void OnSTHJsonParseError(net::URLRequest* request, const std::string& error);
 
+  // Callbacks for parsing the consistency proof's JSON by the SafeJsonParser
+  void OnConsistencyProofJsonParseSuccess(net::URLRequest* request,
+                                          scoped_ptr<base::Value> parsed_json);
+  void OnConsistencyProofJsonParseError(net::URLRequest* request,
+                                        const std::string& error);
+
+  // Creates a new URLRequest with the right flags for log requests.
+  net::URLRequest* CreateRequest(const GURL& url);
+
   net::URLRequestContext* const request_context_;
 
   // Owns the contained requests, as well as FetchState.
   std::map<net::URLRequest*, FetchState*> inflight_requests_;
 
+  std::map<size_t, SignedTreeHeadFetchedCallback> sth_fetch_callbacks_;
+  std::map<size_t, ConsistencyProofFetchedCallback>
+      consistency_fetch_callbacks_;
+
   base::WeakPtrFactory<LogProofFetcher> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(LogProofFetcher);