net/quic/quic_received_packet_manager_test.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/quic/quic_received_packet_manager.h"
   6
   7 #include <algorithm>
   8 #include <vector>
   9
  10 #include "net/quic/quic_connection_stats.h"
  11 #include "net/quic/test_tools/quic_received_packet_manager_peer.h"
  12 #include "testing/gmock/include/gmock/gmock.h"
  13 #include "testing/gtest/include/gtest/gtest.h"
  14
  15 using std::pair;
  16 using std::vector;
  17
  18 namespace net {
  19 namespace test {
  20
  21 class EntropyTrackerPeer {
  22  public:
  23   static QuicPacketNumber first_gap(
  24       const QuicReceivedPacketManager::EntropyTracker& tracker) {
  25     return tracker.first_gap_;
  26   }
  27   static QuicPacketNumber largest_observed(
  28       const QuicReceivedPacketManager::EntropyTracker& tracker) {
  29     return tracker.largest_observed_;
  30   }
  31   static int packets_entropy_size(
  32       const QuicReceivedPacketManager::EntropyTracker& tracker) {
  33     return tracker.packets_entropy_.size();
  34   }
  35   static bool IsTrackingPacket(
  36       const QuicReceivedPacketManager::EntropyTracker& tracker,
  37       QuicPacketNumber packet_number) {
  38     return packet_number >= tracker.first_gap_ &&
  39            packet_number <
  40                (tracker.first_gap_ + tracker.packets_entropy_.size()) &&
  41            tracker.packets_entropy_[packet_number - tracker.first_gap_].second;
  42   }
  43 };
  44
  45 namespace {
  46
  47 // Entropy of individual packets is not tracked if there are no gaps.
  48 TEST(EntropyTrackerTest, NoGaps) {
  49   QuicReceivedPacketManager::EntropyTracker tracker;
  50
  51   tracker.RecordPacketEntropyHash(1, 23);
  52   tracker.RecordPacketEntropyHash(2, 42);
  53
  54   EXPECT_EQ(23 ^ 42, tracker.EntropyHash(2));
  55   EXPECT_EQ(3u, EntropyTrackerPeer::first_gap(tracker));
  56
  57   EXPECT_EQ(2u, EntropyTrackerPeer::largest_observed(tracker));
  58   EXPECT_EQ(0, EntropyTrackerPeer::packets_entropy_size(tracker));
  59   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 1));
  60   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 2));
  61 }
  62
  63 // Entropy of individual packets is tracked as long as there are gaps.
  64 // Filling the first gap results in entropy getting garbage collected.
  65 TEST(EntropyTrackerTest, FillGaps) {
  66   QuicReceivedPacketManager::EntropyTracker tracker;
  67
  68   tracker.RecordPacketEntropyHash(2, 5);
  69   tracker.RecordPacketEntropyHash(5, 17);
  70   tracker.RecordPacketEntropyHash(6, 23);
  71   tracker.RecordPacketEntropyHash(9, 42);
  72
  73   EXPECT_EQ(1u, EntropyTrackerPeer::first_gap(tracker));
  74   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
  75   EXPECT_EQ(9, EntropyTrackerPeer::packets_entropy_size(tracker));
  76
  77   EXPECT_EQ(5, tracker.EntropyHash(2));
  78   EXPECT_EQ(5 ^ 17, tracker.EntropyHash(5));
  79   EXPECT_EQ(5 ^ 17 ^ 23, tracker.EntropyHash(6));
  80   EXPECT_EQ(5 ^ 17 ^ 23 ^ 42, tracker.EntropyHash(9));
  81
  82   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 1));
  83   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 2));
  84   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 5));
  85   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 6));
  86   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 9));
  87
  88   // Fill the gap at 1.
  89   tracker.RecordPacketEntropyHash(1, 2);
  90
  91   EXPECT_EQ(3u, EntropyTrackerPeer::first_gap(tracker));
  92   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
  93   EXPECT_EQ(7, EntropyTrackerPeer::packets_entropy_size(tracker));
  94
  95   EXPECT_EQ(2 ^ 5 ^ 17, tracker.EntropyHash(5));
  96   EXPECT_EQ(2 ^ 5 ^ 17 ^ 23, tracker.EntropyHash(6));
  97   EXPECT_EQ(2 ^ 5 ^ 17 ^ 23 ^ 42, tracker.EntropyHash(9));
  98
  99   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 1));
 100   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 2));
 101   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 5));
 102   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 6));
 103   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 9));
 104
 105   // Fill the gap at 4.
 106   tracker.RecordPacketEntropyHash(4, 2);
 107
 108   EXPECT_EQ(3u, EntropyTrackerPeer::first_gap(tracker));
 109   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
 110   EXPECT_EQ(7, EntropyTrackerPeer::packets_entropy_size(tracker));
 111
 112   EXPECT_EQ(5, tracker.EntropyHash(4));
 113   EXPECT_EQ(5 ^ 17, tracker.EntropyHash(5));
 114   EXPECT_EQ(5 ^ 17 ^ 23, tracker.EntropyHash(6));
 115   EXPECT_EQ(5 ^ 17 ^ 23 ^ 42, tracker.EntropyHash(9));
 116
 117   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 3));
 118   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 4));
 119   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 5));
 120   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 6));
 121   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 9));
 122
 123   // Fill the gap at 3.  Entropy for packets 3 to 6 are forgotten.
 124   tracker.RecordPacketEntropyHash(3, 2);
 125
 126   EXPECT_EQ(7u, EntropyTrackerPeer::first_gap(tracker));
 127   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
 128   EXPECT_EQ(3, EntropyTrackerPeer::packets_entropy_size(tracker));
 129
 130   EXPECT_EQ(2 ^ 5 ^ 17 ^ 23 ^ 42, tracker.EntropyHash(9));
 131
 132   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 3));
 133   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 4));
 134   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 5));
 135   EXPECT_FALSE(EntropyTrackerPeer::IsTrackingPacket(tracker, 6));
 136   EXPECT_TRUE(EntropyTrackerPeer::IsTrackingPacket(tracker, 9));
 137
 138   // Fill in the rest.
 139   tracker.RecordPacketEntropyHash(7, 2);
 140   tracker.RecordPacketEntropyHash(8, 2);
 141
 142   EXPECT_EQ(10u, EntropyTrackerPeer::first_gap(tracker));
 143   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
 144   EXPECT_EQ(0, EntropyTrackerPeer::packets_entropy_size(tracker));
 145
 146   EXPECT_EQ(2 ^ 5 ^ 17 ^ 23 ^ 42, tracker.EntropyHash(9));
 147 }
 148
 149 TEST(EntropyTrackerTest, SetCumulativeEntropyUpTo) {
 150   QuicReceivedPacketManager::EntropyTracker tracker;
 151
 152   tracker.RecordPacketEntropyHash(2, 5);
 153   tracker.RecordPacketEntropyHash(5, 17);
 154   tracker.RecordPacketEntropyHash(6, 23);
 155   tracker.RecordPacketEntropyHash(9, 42);
 156
 157   EXPECT_EQ(1u, EntropyTrackerPeer::first_gap(tracker));
 158   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
 159   EXPECT_EQ(9, EntropyTrackerPeer::packets_entropy_size(tracker));
 160
 161   // Inform the tracker about value of the hash at a gap.
 162   tracker.SetCumulativeEntropyUpTo(3, 7);
 163   EXPECT_EQ(3u, EntropyTrackerPeer::first_gap(tracker));
 164   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
 165   EXPECT_EQ(7, EntropyTrackerPeer::packets_entropy_size(tracker));
 166
 167   EXPECT_EQ(7 ^ 17, tracker.EntropyHash(5));
 168   EXPECT_EQ(7 ^ 17 ^ 23, tracker.EntropyHash(6));
 169   EXPECT_EQ(7 ^ 17 ^ 23 ^ 42, tracker.EntropyHash(9));
 170
 171   // Inform the tracker about value of the hash at a known location.
 172   tracker.SetCumulativeEntropyUpTo(6, 1);
 173   EXPECT_EQ(7u, EntropyTrackerPeer::first_gap(tracker));
 174   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
 175   EXPECT_EQ(3, EntropyTrackerPeer::packets_entropy_size(tracker));
 176
 177   EXPECT_EQ(1 ^ 23 ^ 42, tracker.EntropyHash(9));
 178
 179   // Inform the tracker about value of the hash at the last location.
 180   tracker.SetCumulativeEntropyUpTo(9, 21);
 181   EXPECT_EQ(10u, EntropyTrackerPeer::first_gap(tracker));
 182   EXPECT_EQ(9u, EntropyTrackerPeer::largest_observed(tracker));
 183   EXPECT_EQ(0, EntropyTrackerPeer::packets_entropy_size(tracker));
 184
 185   EXPECT_EQ(42 ^ 21, tracker.EntropyHash(9));
 186 }
 187
 188 class QuicReceivedPacketManagerTest : public ::testing::Test {
 189  protected:
 190   QuicReceivedPacketManagerTest() : received_manager_(&stats_) {}
 191
 192   void RecordPacketReceipt(QuicPacketNumber packet_number,
 193                            QuicPacketEntropyHash entropy_hash) {
 194     RecordPacketReceipt(packet_number, entropy_hash, QuicTime::Zero());
 195   }
 196
 197   void RecordPacketReceipt(QuicPacketNumber packet_number,
 198                            QuicPacketEntropyHash entropy_hash,
 199                            QuicTime receipt_time) {
 200     QuicPacketHeader header;
 201     header.packet_packet_number = packet_number;
 202     header.entropy_hash = entropy_hash;
 203     received_manager_.RecordPacketReceived(0u, header, receipt_time);
 204   }
 205
 206   void RecordPacketRevived(QuicPacketNumber packet_number) {
 207     received_manager_.RecordPacketRevived(packet_number);
 208   }
 209
 210   QuicConnectionStats stats_;
 211   QuicReceivedPacketManager received_manager_;
 212 };
 213
 214 TEST_F(QuicReceivedPacketManagerTest, ReceivedPacketEntropyHash) {
 215   vector<pair<QuicPacketNumber, QuicPacketEntropyHash>> entropies;
 216   entropies.push_back(std::make_pair(1, 12));
 217   entropies.push_back(std::make_pair(7, 1));
 218   entropies.push_back(std::make_pair(2, 33));
 219   entropies.push_back(std::make_pair(5, 3));
 220   entropies.push_back(std::make_pair(8, 34));
 221
 222   for (size_t i = 0; i < entropies.size(); ++i) {
 223     RecordPacketReceipt(entropies[i].first, entropies[i].second);
 224   }
 225
 226   std::sort(entropies.begin(), entropies.end());
 227
 228   QuicPacketEntropyHash hash = 0;
 229   size_t index = 0;
 230   for (size_t i = 1; i <= (*entropies.rbegin()).first; ++i) {
 231     if (entropies[index].first == i) {
 232       hash ^= entropies[index].second;
 233       ++index;
 234     }
 235     if (i < 3) continue;
 236     EXPECT_EQ(hash, received_manager_.EntropyHash(i));
 237   }
 238   // Reorder by 5 when 2 is received after 7.
 239   EXPECT_EQ(5u, stats_.max_sequence_reordering);
 240   EXPECT_EQ(0, stats_.max_time_reordering_us);
 241   EXPECT_EQ(2u, stats_.packets_reordered);
 242 }
 243
 244 TEST_F(QuicReceivedPacketManagerTest, EntropyHashBelowLeastObserved) {
 245   EXPECT_EQ(0, received_manager_.EntropyHash(0));
 246   RecordPacketReceipt(4, 5);
 247   EXPECT_EQ(0, received_manager_.EntropyHash(3));
 248 }
 249
 250 TEST_F(QuicReceivedPacketManagerTest, EntropyHashAboveLargestObserved) {
 251   EXPECT_EQ(0, received_manager_.EntropyHash(0));
 252   RecordPacketReceipt(4, 5);
 253   EXPECT_EQ(0, received_manager_.EntropyHash(3));
 254 }
 255
 256 TEST_F(QuicReceivedPacketManagerTest, SetCumulativeEntropyUpTo) {
 257   vector<pair<QuicPacketNumber, QuicPacketEntropyHash>> entropies;
 258   entropies.push_back(std::make_pair(1, 12));
 259   entropies.push_back(std::make_pair(2, 1));
 260   entropies.push_back(std::make_pair(3, 33));
 261   entropies.push_back(std::make_pair(4, 3));
 262   entropies.push_back(std::make_pair(6, 34));
 263   entropies.push_back(std::make_pair(7, 29));
 264
 265   QuicPacketEntropyHash entropy_hash = 0;
 266   for (size_t i = 0; i < entropies.size(); ++i) {
 267     RecordPacketReceipt(entropies[i].first, entropies[i].second);
 268     entropy_hash ^= entropies[i].second;
 269   }
 270   EXPECT_EQ(entropy_hash, received_manager_.EntropyHash(7));
 271
 272   // Now set the entropy hash up to 5 to be 100.
 273   entropy_hash ^= 100;
 274   for (size_t i = 0; i < 4; ++i) {
 275     entropy_hash ^= entropies[i].second;
 276   }
 277   QuicReceivedPacketManagerPeer::SetCumulativeEntropyUpTo(
 278       &received_manager_, 5, 100);
 279   EXPECT_EQ(entropy_hash, received_manager_.EntropyHash(7));
 280
 281   QuicReceivedPacketManagerPeer::SetCumulativeEntropyUpTo(
 282       &received_manager_, 1, 50);
 283   EXPECT_EQ(entropy_hash, received_manager_.EntropyHash(7));
 284
 285   // No reordering.
 286   EXPECT_EQ(0u, stats_.max_sequence_reordering);
 287   EXPECT_EQ(0, stats_.max_time_reordering_us);
 288   EXPECT_EQ(0u, stats_.packets_reordered);
 289 }
 290
 291 TEST_F(QuicReceivedPacketManagerTest, DontWaitForPacketsBefore) {
 292   QuicPacketHeader header;
 293   header.packet_packet_number = 2u;
 294   received_manager_.RecordPacketReceived(0u, header, QuicTime::Zero());
 295   header.packet_packet_number = 7u;
 296   received_manager_.RecordPacketReceived(0u, header, QuicTime::Zero());
 297   EXPECT_TRUE(received_manager_.IsAwaitingPacket(3u));
 298   EXPECT_TRUE(received_manager_.IsAwaitingPacket(6u));
 299   EXPECT_TRUE(QuicReceivedPacketManagerPeer::DontWaitForPacketsBefore(
 300       &received_manager_, 4));
 301   EXPECT_FALSE(received_manager_.IsAwaitingPacket(3u));
 302   EXPECT_TRUE(received_manager_.IsAwaitingPacket(6u));
 303 }
 304
 305 TEST_F(QuicReceivedPacketManagerTest, UpdateReceivedPacketInfo) {
 306   QuicPacketHeader header;
 307   header.packet_packet_number = 2u;
 308   QuicTime two_ms = QuicTime::Zero().Add(QuicTime::Delta::FromMilliseconds(2));
 309   received_manager_.RecordPacketReceived(0u, header, two_ms);
 310
 311   QuicAckFrame ack;
 312   received_manager_.UpdateReceivedPacketInfo(&ack, QuicTime::Zero());
 313   // When UpdateReceivedPacketInfo with a time earlier than the time of the
 314   // largest observed packet, make sure that the delta is 0, not negative.
 315   EXPECT_EQ(QuicTime::Delta::Zero(), ack.delta_time_largest_observed);
 316   EXPECT_FALSE(ack.received_packet_times.empty());
 317
 318   QuicTime four_ms = QuicTime::Zero().Add(QuicTime::Delta::FromMilliseconds(4));
 319   received_manager_.UpdateReceivedPacketInfo(&ack, four_ms);
 320   // When UpdateReceivedPacketInfo after not having received a new packet,
 321   // the delta should still be accurate.
 322   EXPECT_EQ(QuicTime::Delta::FromMilliseconds(2),
 323             ack.delta_time_largest_observed);
 324 }
 325
 326 TEST_F(QuicReceivedPacketManagerTest, UpdateReceivedConnectionStats) {
 327   RecordPacketReceipt(1, 0);
 328   RecordPacketReceipt(6, 0);
 329   RecordPacketReceipt(
 330       2, 0, QuicTime::Zero().Add(QuicTime::Delta::FromMilliseconds(1)));
 331
 332   EXPECT_EQ(4u, stats_.max_sequence_reordering);
 333   EXPECT_EQ(1000, stats_.max_time_reordering_us);
 334   EXPECT_EQ(1u, stats_.packets_reordered);
 335 }
 336
 337 TEST_F(QuicReceivedPacketManagerTest, RevivedPacket) {
 338   RecordPacketReceipt(1, 0);
 339   RecordPacketReceipt(3, 0);
 340   RecordPacketRevived(2);
 341
 342   QuicAckFrame ack;
 343   received_manager_.UpdateReceivedPacketInfo(&ack, QuicTime::Zero());
 344   EXPECT_EQ(1u, ack.missing_packets.size());
 345   EXPECT_EQ(2u, *ack.missing_packets.begin());
 346   EXPECT_EQ(1u, ack.revived_packets.size());
 347   EXPECT_EQ(2u, *ack.missing_packets.begin());
 348 }
 349
 350 TEST_F(QuicReceivedPacketManagerTest, PacketRevivedThenReceived) {
 351   RecordPacketReceipt(1, 0);
 352   RecordPacketReceipt(3, 0);
 353   RecordPacketRevived(2);
 354   RecordPacketReceipt(2, 0);
 355
 356   QuicAckFrame ack;
 357   received_manager_.UpdateReceivedPacketInfo(&ack, QuicTime::Zero());
 358   EXPECT_TRUE(ack.missing_packets.empty());
 359   EXPECT_TRUE(ack.revived_packets.empty());
 360 }
 361
 362
 363 }  // namespace
 364 }  // namespace test
 365 }  // namespace net