Anti-DDoS enhancements: Log to net log, UMA stats, improved policy.

net/base/backoff_entry_unittest.cc

 // Copyright (c) 2011 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.
 
 #include "net/base/backoff_entry.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 using base::TimeDelta;
 using base::TimeTicks;
 using net::BackoffEntry;
 
 BackoffEntry::Policy base_policy = { 0, 1000, 2.0, 0.0, 20000, 2000 };
 
 class TestBackoffEntry : public BackoffEntry {
  public:
   explicit TestBackoffEntry(const Policy* const policy)
       : BackoffEntry(policy),
         now_(TimeTicks()) {
     // Work around initialization in constructor not picking up
     // fake time.
     SetCustomReleaseTime(TimeTicks());
   }
 
   virtual ~TestBackoffEntry() {}
 
-  virtual TimeTicks GetTimeNow() const {
+  virtual TimeTicks ImplGetTimeNow() const OVERRIDE {
     return now_;
   }
 
   void set_now(const TimeTicks& now) {
     now_ = now;
   }
 
  private:
   TimeTicks now_;
 
@@ skipping 62 matching lines @@
   EXPECT_FALSE(entry.ShouldRejectRequest());
   entry.InformOfRequest(false);
   EXPECT_TRUE(entry.ShouldRejectRequest());
 }
 
 TEST(BackoffEntryTest, ReleaseTimeCalculation) {
   TestBackoffEntry entry(&base_policy);
 
   // With zero errors, should return "now".
   TimeTicks result = entry.GetReleaseTime();
-  EXPECT_EQ(entry.GetTimeNow(), result);
+  EXPECT_EQ(entry.ImplGetTimeNow(), result);
 
   // 1 error.
   entry.InformOfRequest(false);
   result = entry.GetReleaseTime();
-  EXPECT_EQ(entry.GetTimeNow() + TimeDelta::FromMilliseconds(1000), result);
+  EXPECT_EQ(entry.ImplGetTimeNow() + TimeDelta::FromMilliseconds(1000), result);
 
   // 2 errors.
   entry.InformOfRequest(false);
   result = entry.GetReleaseTime();
-  EXPECT_EQ(entry.GetTimeNow() + TimeDelta::FromMilliseconds(2000), result);
+  EXPECT_EQ(entry.ImplGetTimeNow() + TimeDelta::FromMilliseconds(2000), result);
 
   // 3 errors.
   entry.InformOfRequest(false);
   result = entry.GetReleaseTime();
-  EXPECT_EQ(entry.GetTimeNow() + TimeDelta::FromMilliseconds(4000), result);
+  EXPECT_EQ(entry.ImplGetTimeNow() + TimeDelta::FromMilliseconds(4000), result);
 
   // 6 errors (to check it doesn't pass maximum).
   entry.InformOfRequest(false);
   entry.InformOfRequest(false);
   entry.InformOfRequest(false);
   result = entry.GetReleaseTime();
-  EXPECT_EQ(entry.GetTimeNow() + TimeDelta::FromMilliseconds(20000), result);
+  EXPECT_EQ(
+      entry.ImplGetTimeNow() + TimeDelta::FromMilliseconds(20000), result);
 }
 
 TEST(BackoffEntryTest, ReleaseTimeCalculationWithJitter) {
   for (int i = 0; i < 10; ++i) {
     BackoffEntry::Policy jittery_policy = base_policy;
     jittery_policy.jitter_factor = 0.2;
 
     TestBackoffEntry entry(&jittery_policy);
 
     entry.InformOfRequest(false);
     entry.InformOfRequest(false);
     entry.InformOfRequest(false);
     TimeTicks result = entry.GetReleaseTime();
-    EXPECT_LE(entry.GetTimeNow() + TimeDelta::FromMilliseconds(3200), result);
-    EXPECT_GE(entry.GetTimeNow() + TimeDelta::FromMilliseconds(4000), result);
+    EXPECT_LE(
+        entry.ImplGetTimeNow() + TimeDelta::FromMilliseconds(3200), result);
+    EXPECT_GE(
+        entry.ImplGetTimeNow() + TimeDelta::FromMilliseconds(4000), result);
   }
 }
 
 TEST(BackoffEntryTest, FailureThenSuccess) {
   TestBackoffEntry entry(&base_policy);
 
   // Failure count 1, establishes horizon.
   entry.InformOfRequest(false);
   TimeTicks release_time = entry.GetReleaseTime();
   EXPECT_EQ(TimeTicks() + TimeDelta::FromMilliseconds(1000), release_time);
@@ skipping 35 matching lines @@
   BackoffEntry::Policy lenient_policy = base_policy;
   lenient_policy.num_errors_to_ignore = 1;
   TestBackoffEntry custom(&lenient_policy);
   TimeTicks custom_horizon = TimeTicks() + TimeDelta::FromDays(3);
   custom.SetCustomReleaseTime(custom_horizon);
   custom.InformOfRequest(false);  // This must not reset the horizon.
   EXPECT_EQ(custom_horizon, custom.GetReleaseTime());
 }
 
 }  // namespace