network_time_tracker: add temporary time protocol.

This adds queries of the temporary secure time server, with signature
verification, and a very conservative scheduler.  (Checks once per hour,
queries only if sync believed to be lost.)

BUG=589700

Committed: https://crrev.com/ee2016a374b73ba35508ae26837755a23b3defa4
Cr-Commit-Position: refs/heads/master@{#392208}

Review-Url: https://codereview.chromium.org/1835823002
Cr-Commit-Position: refs/heads/master@{#392711}

chrome/browser/browser_process_impl.cc

@@ -268,15 +268,16 @@ void BrowserProcessImpl::StartTearDown() {
   tearing_down_ = true;
   DCHECK(IsShuttingDown());
   // We need to destroy the MetricsServicesManager, IntranetRedirectDetector,
-  // PromoResourceService, and SafeBrowsing ClientSideDetectionService (owned by
-  // the SafeBrowsingService) before the io_thread_ gets destroyed, since their
-  // destructors can call the URLFetcher destructor, which does a
-  // PostDelayedTask operation on the IO thread. (The IO thread will handle that
-  // URLFetcher operation before going away.)
+  // PromoResourceService, NetworkTimeTracker, and SafeBrowsing
+  // ClientSideDetectionService (owned by the SafeBrowsingService) before the
+  // io_thread_ gets destroyed, since their destructors can call the URLFetcher
+  // destructor, which does a PostDelayedTask operation on the IO thread. (The
+  // IO thread will handle that URLFetcher operation before going away.)
   metrics_services_manager_.reset();
   intranet_redirect_detector_.reset();
   if (safe_browsing_service_.get())
     safe_browsing_service()->ShutDown();
+  network_time_tracker_.reset();
 #if defined(ENABLE_PLUGIN_INSTALLATION)
   plugins_resource_service_.reset();
 #endif
@@ -747,7 +748,8 @@ network_time::NetworkTimeTracker* BrowserProcessImpl::network_time_tracker() {
   if (!network_time_tracker_) {
     network_time_tracker_.reset(new network_time::NetworkTimeTracker(
         base::WrapUnique(new base::DefaultClock()),
-        base::WrapUnique(new base::DefaultTickClock()), local_state()));
+        base::WrapUnique(new base::DefaultTickClock()), local_state(),
+        system_request_context()));
   }
   return network_time_tracker_.get();
 }

chrome/test/base/testing_browser_process.cc

@@ -357,7 +357,7 @@ TestingBrowserProcess::network_time_tracker() {
     network_time_tracker_.reset(new network_time::NetworkTimeTracker(
         std::unique_ptr<base::Clock>(new base::DefaultClock()),
         std::unique_ptr<base::TickClock>(new base::DefaultTickClock()),
-        local_state_));
+        local_state_, system_request_context()));
   }
   return network_time_tracker_.get();
 }

components/client_update_protocol/ecdsa.cc

@@ -98,9 +98,13 @@ std::unique_ptr<Ecdsa> Ecdsa::Create(int key_version,
   return base::WrapUnique(new Ecdsa(key_version, public_key));
 }
 
+void Ecdsa::OverrideNonceForTesting(int key_version, uint32_t nonce) {
+  DCHECK(!request_query_cup2key_.empty());
+  request_query_cup2key_ = base::StringPrintf("%d:%u", pub_key_version_, nonce);
+}
+
 void Ecdsa::SignRequest(const base::StringPiece& request_body,
                         std::string* query_params) {
-  DCHECK(!request_body.empty());
   DCHECK(query_params);
 
   // Generate a random nonce to use for freshness, build the cup2key query

components/client_update_protocol/ecdsa.h

@@ -51,16 +51,18 @@ class Ecdsa {
 
   // 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);
 
- private:
-  friend class CupEcdsaTest;
+  // 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:
   Ecdsa(int key_version, const base::StringPiece& public_key);
 
   // The server keeps multiple signing keys; a version must be sent so that

components/client_update_protocol/ecdsa_unittest.cc

@@ -46,11 +46,6 @@ class CupEcdsaTest : public testing::Test {
     ASSERT_TRUE(cup_.get());
   }
 
-  void OverrideNonce(uint32_t nonce) {
-    cup_->request_query_cup2key_ =
-        base::StringPrintf("%d:%u", cup_->pub_key_version_, nonce);
-  }
-
   Ecdsa& CUP() { return *cup_.get(); }
 
  private:
@@ -86,7 +81,7 @@ TEST_F(CupEcdsaTest, ValidateResponse_TestETagParsing) {
   // Invalid ETags must be gracefully rejected without a crash.
   std::string query_discard;
   CUP().SignRequest("Request_A", &query_discard);
-  OverrideNonce(12345);
+  CUP().OverrideNonceForTesting(8, 12345);
 
   // Expect a pass for a well-formed etag.
   EXPECT_TRUE(CUP().ValidateResponse(
@@ -238,7 +233,7 @@ TEST_F(CupEcdsaTest, ValidateResponse_TestETagParsing) {
 TEST_F(CupEcdsaTest, ValidateResponse_TestSigning) {
   std::string query_discard;
   CUP().SignRequest("Request_A", &query_discard);
-  OverrideNonce(12345);
+  CUP().OverrideNonceForTesting(8, 12345);
 
   // How to generate an ECDSA signature:
   //   echo -n Request_A | sha256sum | cut -d " " -f 1 > h

components/network_time/BUILD.gn

@@ -13,7 +13,9 @@ static_library("network_time") {
   deps = [
     "//base",
     "//base:i18n",
+    "//components/client_update_protocol",
     "//components/prefs",
+    "//net",
   ]
 }
 
@@ -27,7 +29,10 @@ source_set("unit_tests") {
     ":network_time",
     "//base",
     "//base/test:test_support",
+    "//components/client_update_protocol",
     "//components/prefs:test_support",
+    "//net",
+    "//net:test_support",
     "//testing/gtest",
   ]
 }

components/network_time/DEPS

@@ -1,3 +1,5 @@
 include_rules = [
+  "+components/client_update_protocol",
   "+components/prefs",
+  "+net",
 ]