Certificate Transparency: Start tracking logs' state

components/certificate_transparency/tree_state_tracker.h

Index: components/certificate_transparency/tree_state_tracker.h
diff --git a/components/certificate_transparency/tree_state_tracker.h b/components/certificate_transparency/tree_state_tracker.h
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+++ b/components/certificate_transparency/tree_state_tracker.h
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+// Copyright 2015 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_CERTIFICATE_TRANSPARENCY_TREE_STATE_TRACKER_H_
+#define COMPONENTS_CERTIFICATE_TRANSPARENCY_TREE_STATE_TRACKER_H_
+
+#include <map>
+#include <set>
+#include <string>
+#include <vector>
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "net/cert/ct_observer.h"
+
+namespace net {
+class CTLogVerifier;
+class X509Certificate;
+
+namespace ct {
+struct SignedCertificateTimestamp;
+struct SignedTreeHead;
+}  // namespace ct
+
+}  // namespace net
+
+namespace certificate_transparency {
+
+// Tracks the state of the Merkle Trees of CT logs Chromium
+// knows about. For now, only stores Signed Tree Heads.
+class TreeStateTracker : public net::ct::CTObserver {
+ public:
+  explicit TreeStateTracker(
+      const std::vector<scoped_refptr<const net::CTLogVerifier>>& ct_logs);
+  ~TreeStateTracker() override;
+
+  void OnSCTVerified(net::X509Certificate* cert,
+                     const net::ct::SignedCertificateTimestamp* sct) override;
+
+  void NewSTHObserved(const net::ct::SignedTreeHead& sth) override;
+
+ private:
+  void LoadSTHs();
+
+  // Handling TreeStateStorage results
+  void OnSTHLoaded(const net::ct::SignedTreeHead& sth);
+
+  // Update the STH in the map and on disk.
+  void UpdateVerifiedSTH(const std::string& log_id,
+                         const net::ct::SignedTreeHead& verified_sth);
+
+  // Holds the latest STH fetched and verified for each log.
+  std::map<std::string, net::ct::SignedTreeHead> verified_sths_;
+  // List of CT logs to track.
+  std::map<std::string, scoped_refptr<const net::CTLogVerifier>> ct_logs_;
+  // List of SCTs for each log.
+  /*
+  std::map<std::string, std::set<scoped_refptr<ct::SignedCertificateTimestamp>>>
+      pending_scts_;
+      */
+  // Is load pending?
+  bool initial_load_pending_;
+
+  DISALLOW_COPY_AND_ASSIGN(TreeStateTracker);
+};
+
+}  // namespace certificate_transparency
+
+#endif  // COMPONENTS_CERTIFICATE_TRANSPARENCY_TREE_STATE_TRACKER_H_