Change the wire format of the ack frame to include a compressed version

net/quic/quic_framer_test.cc

 // Copyright (c) 2012 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/quic/quic_framer.h"
 
 #include <algorithm>
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 442 matching lines @@
 
   // Checks if the supplied string matches data in the supplied StreamFrame.
   void CheckStreamFrameData(string str, QuicStreamFrame* frame) {
     scoped_ptr<string> frame_data(frame->GetDataAsString());
     EXPECT_EQ(str, *frame_data);
   }
 
   void CheckStreamFrameBoundaries(unsigned char* packet,
                                   size_t stream_id_size,
                                   bool include_version) {
-    // Now test framing boundaries
+    // Now test framing boundaries.
     for (size_t i = kQuicFrameTypeSize; i < GetMinStreamFrameSize(); ++i) {
       string expected_error;
       if (i < kQuicFrameTypeSize + stream_id_size) {
         expected_error = "Unable to read stream_id.";
       } else if (i < kQuicFrameTypeSize + stream_id_size +
                  kQuicMaxStreamOffsetSize) {
         expected_error = "Unable to read offset.";
       } else {
         expected_error = "Unable to read frame data.";
       }
@@ skipping 201 matching lines @@
   EXPECT_FALSE(visitor_.header_->public_header.reset_flag);
   EXPECT_FALSE(visitor_.header_->public_header.version_flag);
   EXPECT_FALSE(visitor_.header_->fec_flag);
   EXPECT_FALSE(visitor_.header_->entropy_flag);
   EXPECT_EQ(0, visitor_.header_->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.header_->packet_sequence_number);
   EXPECT_EQ(NOT_IN_FEC_GROUP, visitor_.header_->is_in_fec_group);
   EXPECT_EQ(0x00u, visitor_.header_->fec_group);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0;
        i < GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP);
        ++i) {
     string expected_error;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
     } else if (i < GetSequenceNumberOffset(!kIncludeVersion)) {
       expected_error = "Unable to read ConnectionId.";
     } else if (i < GetPrivateFlagsOffset(!kIncludeVersion)) {
@@ skipping 32 matching lines @@
   EXPECT_FALSE(visitor_.header_->public_header.reset_flag);
   EXPECT_FALSE(visitor_.header_->public_header.version_flag);
   EXPECT_FALSE(visitor_.header_->fec_flag);
   EXPECT_FALSE(visitor_.header_->entropy_flag);
   EXPECT_EQ(0, visitor_.header_->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.header_->packet_sequence_number);
   EXPECT_EQ(NOT_IN_FEC_GROUP, visitor_.header_->is_in_fec_group);
   EXPECT_EQ(0x00u, visitor_.header_->fec_group);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0;
        i < GetPacketHeaderSize(PACKET_4BYTE_CONNECTION_ID, !kIncludeVersion,
                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP);
        ++i) {
     string expected_error;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
     } else if (i < GetSequenceNumberOffset(PACKET_4BYTE_CONNECTION_ID,
                                            !kIncludeVersion)) {
       expected_error = "Unable to read ConnectionId.";
@@ skipping 35 matching lines @@
   EXPECT_FALSE(visitor_.header_->public_header.reset_flag);
   EXPECT_FALSE(visitor_.header_->public_header.version_flag);
   EXPECT_FALSE(visitor_.header_->fec_flag);
   EXPECT_FALSE(visitor_.header_->entropy_flag);
   EXPECT_EQ(0, visitor_.header_->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.header_->packet_sequence_number);
   EXPECT_EQ(NOT_IN_FEC_GROUP, visitor_.header_->is_in_fec_group);
   EXPECT_EQ(0x00u, visitor_.header_->fec_group);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0;
        i < GetPacketHeaderSize(PACKET_1BYTE_CONNECTION_ID, !kIncludeVersion,
                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP);
        ++i) {
     string expected_error;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
     } else if (i < GetSequenceNumberOffset(PACKET_1BYTE_CONNECTION_ID,
                                            !kIncludeVersion)) {
       expected_error = "Unable to read ConnectionId.";
@@ skipping 34 matching lines @@
   EXPECT_FALSE(visitor_.header_->public_header.reset_flag);
   EXPECT_FALSE(visitor_.header_->public_header.version_flag);
   EXPECT_FALSE(visitor_.header_->fec_flag);
   EXPECT_FALSE(visitor_.header_->entropy_flag);
   EXPECT_EQ(0, visitor_.header_->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.header_->packet_sequence_number);
   EXPECT_EQ(NOT_IN_FEC_GROUP, visitor_.header_->is_in_fec_group);
   EXPECT_EQ(0x00u, visitor_.header_->fec_group);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0;
        i < GetPacketHeaderSize(PACKET_0BYTE_CONNECTION_ID, !kIncludeVersion,
                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP);
        ++i) {
     string expected_error;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
     } else if (i < GetSequenceNumberOffset(PACKET_0BYTE_CONNECTION_ID,
                                            !kIncludeVersion)) {
       expected_error = "Unable to read ConnectionId.";
@@ skipping 36 matching lines @@
   EXPECT_TRUE(visitor_.header_->public_header.version_flag);
   EXPECT_EQ(GetParam(), visitor_.header_->public_header.versions[0]);
   EXPECT_FALSE(visitor_.header_->fec_flag);
   EXPECT_FALSE(visitor_.header_->entropy_flag);
   EXPECT_EQ(0, visitor_.header_->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.header_->packet_sequence_number);
   EXPECT_EQ(NOT_IN_FEC_GROUP, visitor_.header_->is_in_fec_group);
   EXPECT_EQ(0x00u, visitor_.header_->fec_group);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0;
        i < GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, kIncludeVersion,
                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP);
        ++i) {
     string expected_error;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
     } else if (i < kVersionOffset) {
       expected_error = "Unable to read ConnectionId.";
     } else if (i <  GetSequenceNumberOffset(kIncludeVersion)) {
@@ skipping 34 matching lines @@
   EXPECT_FALSE(visitor_.header_->public_header.reset_flag);
   EXPECT_FALSE(visitor_.header_->public_header.version_flag);
   EXPECT_FALSE(visitor_.header_->fec_flag);
   EXPECT_FALSE(visitor_.header_->entropy_flag);
   EXPECT_EQ(0, visitor_.header_->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.header_->packet_sequence_number);
   EXPECT_EQ(NOT_IN_FEC_GROUP, visitor_.header_->is_in_fec_group);
   EXPECT_EQ(0x00u, visitor_.header_->fec_group);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0;
        i < GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
                                PACKET_4BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP);
        ++i) {
     string expected_error;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
     } else if (i < GetSequenceNumberOffset(!kIncludeVersion)) {
       expected_error = "Unable to read ConnectionId.";
     } else if (i < GetPrivateFlagsOffset(!kIncludeVersion,
@@ skipping 34 matching lines @@
   EXPECT_FALSE(visitor_.header_->public_header.reset_flag);
   EXPECT_FALSE(visitor_.header_->public_header.version_flag);
   EXPECT_FALSE(visitor_.header_->fec_flag);
   EXPECT_FALSE(visitor_.header_->entropy_flag);
   EXPECT_EQ(0, visitor_.header_->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.header_->packet_sequence_number);
   EXPECT_EQ(NOT_IN_FEC_GROUP, visitor_.header_->is_in_fec_group);
   EXPECT_EQ(0x00u, visitor_.header_->fec_group);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0;
        i < GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
                                PACKET_2BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP);
        ++i) {
     string expected_error;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
     } else if (i < GetSequenceNumberOffset(!kIncludeVersion)) {
       expected_error = "Unable to read ConnectionId.";
     } else if (i < GetPrivateFlagsOffset(!kIncludeVersion,
@@ skipping 34 matching lines @@
   EXPECT_FALSE(visitor_.header_->public_header.reset_flag);
   EXPECT_FALSE(visitor_.header_->public_header.version_flag);
   EXPECT_FALSE(visitor_.header_->fec_flag);
   EXPECT_FALSE(visitor_.header_->entropy_flag);
   EXPECT_EQ(0, visitor_.header_->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.header_->packet_sequence_number);
   EXPECT_EQ(NOT_IN_FEC_GROUP, visitor_.header_->is_in_fec_group);
   EXPECT_EQ(0x00u, visitor_.header_->fec_group);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0;
        i < GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
                                PACKET_1BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP);
        ++i) {
     string expected_error;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
     } else if (i < GetSequenceNumberOffset(!kIncludeVersion)) {
       expected_error = "Unable to read ConnectionId.";
     } else if (i < GetPrivateFlagsOffset(!kIncludeVersion,
@@ skipping 218 matching lines @@
 
   ASSERT_EQ(1u, visitor_.stream_frames_.size());
   EXPECT_EQ(0u, visitor_.ack_frames_.size());
   EXPECT_EQ(static_cast<uint64>(0x01020304),
             visitor_.stream_frames_[0]->stream_id);
   EXPECT_TRUE(visitor_.stream_frames_[0]->fin);
   EXPECT_EQ(GG_UINT64_C(0xBA98FEDC32107654),
             visitor_.stream_frames_[0]->offset);
   CheckStreamFrameData("hello world!", visitor_.stream_frames_[0]);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   CheckStreamFrameBoundaries(packet, kQuicMaxStreamIdSize, !kIncludeVersion);
 }
 
 TEST_P(QuicFramerTest, StreamFrame3ByteStreamId) {
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
     0x3C,
     // connection_id
     0x10, 0x32, 0x54, 0x76,
     0x98, 0xBA, 0xDC, 0xFE,
@@ skipping 27 matching lines @@
 
   ASSERT_EQ(1u, visitor_.stream_frames_.size());
   EXPECT_EQ(0u, visitor_.ack_frames_.size());
   EXPECT_EQ(GG_UINT64_C(0x00020304),
             visitor_.stream_frames_[0]->stream_id);
   EXPECT_TRUE(visitor_.stream_frames_[0]->fin);
   EXPECT_EQ(GG_UINT64_C(0xBA98FEDC32107654),
             visitor_.stream_frames_[0]->offset);
   CheckStreamFrameData("hello world!", visitor_.stream_frames_[0]);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   const size_t stream_id_size = 3;
   CheckStreamFrameBoundaries(packet, stream_id_size, !kIncludeVersion);
 }
 
 TEST_P(QuicFramerTest, StreamFrame2ByteStreamId) {
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
     0x3C,
     // connection_id
     0x10, 0x32, 0x54, 0x76,
@@ skipping 28 matching lines @@
 
   ASSERT_EQ(1u, visitor_.stream_frames_.size());
   EXPECT_EQ(0u, visitor_.ack_frames_.size());
   EXPECT_EQ(static_cast<uint64>(0x00000304),
             visitor_.stream_frames_[0]->stream_id);
   EXPECT_TRUE(visitor_.stream_frames_[0]->fin);
   EXPECT_EQ(GG_UINT64_C(0xBA98FEDC32107654),
             visitor_.stream_frames_[0]->offset);
   CheckStreamFrameData("hello world!", visitor_.stream_frames_[0]);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   const size_t stream_id_size = 2;
   CheckStreamFrameBoundaries(packet, stream_id_size, !kIncludeVersion);
 }
 
 TEST_P(QuicFramerTest, StreamFrame1ByteStreamId) {
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
     0x3C,
     // connection_id
     0x10, 0x32, 0x54, 0x76,
@@ skipping 28 matching lines @@
 
   ASSERT_EQ(1u, visitor_.stream_frames_.size());
   EXPECT_EQ(0u, visitor_.ack_frames_.size());
   EXPECT_EQ(static_cast<uint64>(0x00000004),
             visitor_.stream_frames_[0]->stream_id);
   EXPECT_TRUE(visitor_.stream_frames_[0]->fin);
   EXPECT_EQ(GG_UINT64_C(0xBA98FEDC32107654),
             visitor_.stream_frames_[0]->offset);
   CheckStreamFrameData("hello world!", visitor_.stream_frames_[0]);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   const size_t stream_id_size = 1;
   CheckStreamFrameBoundaries(packet, stream_id_size, !kIncludeVersion);
 }
 
 TEST_P(QuicFramerTest, StreamFrameWithVersion) {
   unsigned char packet[] = {
     // public flags (version, 8 byte connection_id)
     0x3D,
     // connection_id
     0x10, 0x32, 0x54, 0x76,
@@ skipping 32 matching lines @@
 
   ASSERT_EQ(1u, visitor_.stream_frames_.size());
   EXPECT_EQ(0u, visitor_.ack_frames_.size());
   EXPECT_EQ(static_cast<uint64>(0x01020304),
             visitor_.stream_frames_[0]->stream_id);
   EXPECT_TRUE(visitor_.stream_frames_[0]->fin);
   EXPECT_EQ(GG_UINT64_C(0xBA98FEDC32107654),
             visitor_.stream_frames_[0]->offset);
   CheckStreamFrameData("hello world!", visitor_.stream_frames_[0]);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   CheckStreamFrameBoundaries(packet, kQuicMaxStreamIdSize, kIncludeVersion);
 }
 
 TEST_P(QuicFramerTest, RejectPacket) {
   visitor_.accept_packet_ = false;
 
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
     0x3C,
     // connection_id
@@ skipping 155 matching lines @@
 
   ASSERT_EQ(1u, visitor_.stream_frames_.size());
   EXPECT_EQ(0u, visitor_.ack_frames_.size());
   EXPECT_EQ(GG_UINT64_C(0x01020304), visitor_.stream_frames_[0]->stream_id);
   EXPECT_TRUE(visitor_.stream_frames_[0]->fin);
   EXPECT_EQ(GG_UINT64_C(0xBA98FEDC32107654),
             visitor_.stream_frames_[0]->offset);
   CheckStreamFrameData("hello world!", visitor_.stream_frames_[0]);
 }
 
-TEST_P(QuicFramerTest, AckFrame) {
+TEST_P(QuicFramerTest, AckFramev22) {
+  if (version_ > QUIC_VERSION_22) {
+    return;
+  }
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
     0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
+    0x6C,
+    // entropy hash of all received packets.
+    0xBA,
+    // largest observed packet sequence number
+    0xBF, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // Zero delta time.
+    0x0, 0x0,
+    // num missing packets
+    0x01,
+    // missing packet delta
+    0x01,
+    // 0 more missing packets in range.
+    0x00,
+    // Number of revived packets.
+    0x00,
+  };
+
+  QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
+  EXPECT_TRUE(framer_.ProcessPacket(encrypted));
+
+  EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
+  ASSERT_TRUE(visitor_.header_.get());
+  EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
+
+  EXPECT_EQ(0u, visitor_.stream_frames_.size());
+  ASSERT_EQ(1u, visitor_.ack_frames_.size());
+  const QuicAckFrame& frame = *visitor_.ack_frames_[0];
+  EXPECT_EQ(0xBA, frame.entropy_hash);
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABF), frame.largest_observed);
+  ASSERT_EQ(1u, frame.missing_packets.size());
+  SequenceNumberSet::const_iterator missing_iter =
+      frame.missing_packets.begin();
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABE), *missing_iter);
+
+  const size_t kReceivedEntropyOffset = kQuicFrameTypeSize;
+  const size_t kLargestObservedOffset = kReceivedEntropyOffset +
+      kQuicEntropyHashSize;
+  const size_t kMissingDeltaTimeOffset = kLargestObservedOffset +
+      PACKET_6BYTE_SEQUENCE_NUMBER;
+  const size_t kNumMissingPacketOffset = kMissingDeltaTimeOffset +
+      kQuicDeltaTimeLargestObservedSize;
+  const size_t kMissingPacketsOffset = kNumMissingPacketOffset +
+      kNumberOfNackRangesSize;
+  const size_t kMissingPacketsRange = kMissingPacketsOffset +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  const size_t kRevivedPacketsLength = kMissingPacketsRange +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  // Now test framing boundaries.
+  const size_t ack_frame_size = kRevivedPacketsLength +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  for (size_t i = kQuicFrameTypeSize; i < ack_frame_size; ++i) {
+    string expected_error;
+    if (i < kLargestObservedOffset) {
+      expected_error = "Unable to read entropy hash for received packets.";
+    } else if (i < kMissingDeltaTimeOffset) {
+      expected_error = "Unable to read largest observed.";
+    } else if (i < kNumMissingPacketOffset) {
+      expected_error = "Unable to read delta time largest observed.";
+    } else if (i < kMissingPacketsOffset) {
+      expected_error = "Unable to read num missing packet ranges.";
+    } else if (i < kMissingPacketsRange) {
+      expected_error = "Unable to read missing sequence number delta.";
+    } else if (i < kRevivedPacketsLength) {
+      expected_error = "Unable to read missing sequence number range.";
+    } else {
+      expected_error = "Unable to read num revived packets.";
+    }
+    CheckProcessingFails(
+        packet,
+        i + GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
+                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP),
+        expected_error, QUIC_INVALID_ACK_DATA);
+  }
+}
+
+
+TEST_P(QuicFramerTest, AckFrameTwoTimestamp) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
+    0x6C,
+    // entropy hash of all received packets.
+    0xBA,
+    // largest observed packet sequence number
+    0xBF, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // Zero delta time.
+    0x0, 0x0,
+    // Number of timestamps.
+    0x02,
+    // Delta from largest observed.
+    0x01,
+    // Delta time.
+    0x10, 0x32, 0x54, 0x76,
+    // Delta from largest observed.
+    0x02,
+    // Delta time.
+    0x10, 0x32,
+    // num missing packets
+    0x01,
+    // missing packet delta
+    0x01,
+    // 0 more missing packets in range.
+    0x00,
+    // Number of revived packets.
+    0x00,
+  };
+
+  QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
+  EXPECT_TRUE(framer_.ProcessPacket(encrypted));
+
+  EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
+  ASSERT_TRUE(visitor_.header_.get());
+  EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
+
+  EXPECT_EQ(0u, visitor_.stream_frames_.size());
+  ASSERT_EQ(1u, visitor_.ack_frames_.size());
+  const QuicAckFrame& frame = *visitor_.ack_frames_[0];
+  EXPECT_EQ(0xBA, frame.entropy_hash);
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABF), frame.largest_observed);
+  ASSERT_EQ(1u, frame.missing_packets.size());
+  ASSERT_EQ(2u, frame.received_packet_times.size());
+  SequenceNumberSet::const_iterator missing_iter =
+      frame.missing_packets.begin();
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABE), *missing_iter);
+
+  const size_t kReceivedEntropyOffset = kQuicFrameTypeSize;
+  const size_t kLargestObservedOffset = kReceivedEntropyOffset +
+      kQuicEntropyHashSize;
+  const size_t kMissingDeltaTimeOffset = kLargestObservedOffset +
+      PACKET_6BYTE_SEQUENCE_NUMBER;
+  const size_t kNumTimestampsOffset = kMissingDeltaTimeOffset +
+      kQuicDeltaTimeLargestObservedSize;
+  const size_t kTimestampDeltaLargestObserved1 = kNumTimestampsOffset +
+      kQuicNumTimestampsSize;
+  const size_t kTimestampTimeDeltaLargestObserved1 =
+      kTimestampDeltaLargestObserved1 + 1;
+  const size_t kTimestampDeltaLargestObserved2 =
+      kTimestampTimeDeltaLargestObserved1 + 4;
+  const size_t kTimestampTimeDeltaLargestObserved2 =
+      kTimestampDeltaLargestObserved2 + 1;
+  const size_t kNumMissingPacketOffset =
+      kTimestampTimeDeltaLargestObserved2 + 2;
+  const size_t kMissingPacketsOffset = kNumMissingPacketOffset +
+      kNumberOfNackRangesSize;
+  const size_t kMissingPacketsRange = kMissingPacketsOffset +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  const size_t kRevivedPacketsLength = kMissingPacketsRange +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  // Now test framing boundaries.
+  const size_t ack_frame_size = kRevivedPacketsLength +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  for (size_t i = kQuicFrameTypeSize; i < ack_frame_size; ++i) {
+    string expected_error;
+    if (i < kLargestObservedOffset) {
+      expected_error = "Unable to read entropy hash for received packets.";
+    } else if (i < kMissingDeltaTimeOffset) {
+      expected_error = "Unable to read largest observed.";
+    } else if (i < kNumTimestampsOffset) {
+      expected_error = "Unable to read delta time largest observed.";
+    } else if (i < kTimestampDeltaLargestObserved1) {
+      expected_error = "Unable to read num received packets.";
+    } else if (i < kTimestampTimeDeltaLargestObserved1) {
+      expected_error = "Unable to read sequence delta in received packets.";
+    } else if (i < kTimestampDeltaLargestObserved2) {
+      expected_error = "Unable to read time delta in received packets.";
+    } else if (i < kTimestampTimeDeltaLargestObserved2) {
+      expected_error = "Unable to read sequence delta in received packets.";
+    } else if (i < kNumMissingPacketOffset) {
+      expected_error =
+          "Unable to read incremental time delta in received packets.";
+    } else if (i < kMissingPacketsOffset) {
+      expected_error = "Unable to read num missing packet ranges.";
+    } else if (i < kMissingPacketsRange) {
+      expected_error = "Unable to read missing sequence number delta.";
+    } else if (i < kRevivedPacketsLength) {
+      expected_error = "Unable to read missing sequence number range.";
+    } else {
+      expected_error = "Unable to read num revived packets.";
+    }
+    CheckProcessingFails(
+        packet,
+        i + GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
+                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP),
+        expected_error, QUIC_INVALID_ACK_DATA);
+  }
+}
+
+
+TEST_P(QuicFramerTest, AckFrameOneTimestamp) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
+    0x6C,
+    // entropy hash of all received packets.
+    0xBA,
+    // largest observed packet sequence number
+    0xBF, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // Zero delta time.
+    0x0, 0x0,
+    // Number of timestamps.
+    0x01,
+    // Delta from largest observed.
+    0x01,
+    // Delta time.
+    0x10, 0x32, 0x54, 0x76,
+    // num missing packets
+    0x01,
+    // missing packet delta
+    0x01,
+    // 0 more missing packets in range.
+    0x00,
+    // Number of revived packets.
+    0x00,
+  };
+
+  QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
+  EXPECT_TRUE(framer_.ProcessPacket(encrypted));
+
+  EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
+  ASSERT_TRUE(visitor_.header_.get());
+  EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
+
+  EXPECT_EQ(0u, visitor_.stream_frames_.size());
+  ASSERT_EQ(1u, visitor_.ack_frames_.size());
+  const QuicAckFrame& frame = *visitor_.ack_frames_[0];
+  EXPECT_EQ(0xBA, frame.entropy_hash);
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABF), frame.largest_observed);
+  ASSERT_EQ(1u, frame.missing_packets.size());
+  ASSERT_EQ(1u, frame.received_packet_times.size());
+  SequenceNumberSet::const_iterator missing_iter =
+      frame.missing_packets.begin();
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABE), *missing_iter);
+
+  const size_t kReceivedEntropyOffset = kQuicFrameTypeSize;
+  const size_t kLargestObservedOffset = kReceivedEntropyOffset +
+      kQuicEntropyHashSize;
+  const size_t kMissingDeltaTimeOffset = kLargestObservedOffset +
+      PACKET_6BYTE_SEQUENCE_NUMBER;
+  const size_t kNumTimestampsOffset = kMissingDeltaTimeOffset +
+      kQuicDeltaTimeLargestObservedSize;
+  const size_t kTimestampDeltaLargestObserved = kNumTimestampsOffset +
+      kQuicNumTimestampsSize;
+  const size_t kTimestampTimeDeltaLargestObserved =
+    kTimestampDeltaLargestObserved + 1;
+  const size_t kNumMissingPacketOffset = kTimestampTimeDeltaLargestObserved + 4;
+  const size_t kMissingPacketsOffset = kNumMissingPacketOffset +
+      kNumberOfNackRangesSize;
+  const size_t kMissingPacketsRange = kMissingPacketsOffset +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  const size_t kRevivedPacketsLength = kMissingPacketsRange +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  // Now test framing boundaries.
+  const size_t ack_frame_size = kRevivedPacketsLength +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  for (size_t i = kQuicFrameTypeSize; i < ack_frame_size; ++i) {
+    string expected_error;
+    if (i < kLargestObservedOffset) {
+      expected_error = "Unable to read entropy hash for received packets.";
+    } else if (i < kMissingDeltaTimeOffset) {
+      expected_error = "Unable to read largest observed.";
+    } else if (i < kNumTimestampsOffset) {
+      expected_error = "Unable to read delta time largest observed.";
+    } else if (i < kTimestampDeltaLargestObserved) {
+      expected_error = "Unable to read num received packets.";
+    } else if (i < kTimestampTimeDeltaLargestObserved) {
+      expected_error = "Unable to read sequence delta in received packets.";
+    } else if (i < kNumMissingPacketOffset) {
+      expected_error = "Unable to read time delta in received packets.";
+    } else if (i < kMissingPacketsOffset) {
+      expected_error = "Unable to read num missing packet ranges.";
+    } else if (i < kMissingPacketsRange) {
+      expected_error = "Unable to read missing sequence number delta.";
+    } else if (i < kRevivedPacketsLength) {
+      expected_error = "Unable to read missing sequence number range.";
+    } else {
+      expected_error = "Unable to read num revived packets.";
+    }
+    CheckProcessingFails(
+        packet,
+        i + GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
+                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP),
+        expected_error, QUIC_INVALID_ACK_DATA);
+  }
+}
+
+
+TEST_P(QuicFramerTest, AckFrame) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
+    0x6C,
+    // entropy hash of all received packets.
+    0xBA,
+    // largest observed packet sequence number
+    0xBF, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // Zero delta time.
+    0x0, 0x0,
+    // Number of timestamps.
+    0x00,
+    // num missing packets
+    0x01,
+    // missing packet delta
+    0x01,
+    // 0 more missing packets in range.
+    0x00,
+    // Number of revived packets.
+    0x00,
+  };
+
+  QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
+  EXPECT_TRUE(framer_.ProcessPacket(encrypted));
+
+  EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
+  ASSERT_TRUE(visitor_.header_.get());
+  EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
+
+  EXPECT_EQ(0u, visitor_.stream_frames_.size());
+  ASSERT_EQ(1u, visitor_.ack_frames_.size());
+  const QuicAckFrame& frame = *visitor_.ack_frames_[0];
+  EXPECT_EQ(0xBA, frame.entropy_hash);
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABF), frame.largest_observed);
+  ASSERT_EQ(1u, frame.missing_packets.size());
+  SequenceNumberSet::const_iterator missing_iter =
+      frame.missing_packets.begin();
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABE), *missing_iter);
+
+  const size_t kReceivedEntropyOffset = kQuicFrameTypeSize;
+  const size_t kLargestObservedOffset = kReceivedEntropyOffset +
+      kQuicEntropyHashSize;
+  const size_t kMissingDeltaTimeOffset = kLargestObservedOffset +
+      PACKET_6BYTE_SEQUENCE_NUMBER;
+  const size_t kNumTimestampsOffset = kMissingDeltaTimeOffset +
+      kQuicDeltaTimeLargestObservedSize;
+  const size_t kNumMissingPacketOffset = kNumTimestampsOffset +
+      kQuicNumTimestampsSize;
+  const size_t kMissingPacketsOffset = kNumMissingPacketOffset +
+      kNumberOfNackRangesSize;
+  const size_t kMissingPacketsRange = kMissingPacketsOffset +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  const size_t kRevivedPacketsLength = kMissingPacketsRange +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  // Now test framing boundaries.
+  const size_t ack_frame_size = kRevivedPacketsLength +
+      PACKET_1BYTE_SEQUENCE_NUMBER;
+  for (size_t i = kQuicFrameTypeSize; i < ack_frame_size; ++i) {
+    string expected_error;
+    if (i < kLargestObservedOffset) {
+      expected_error = "Unable to read entropy hash for received packets.";
+    } else if (i < kMissingDeltaTimeOffset) {
+      expected_error = "Unable to read largest observed.";
+    } else if (i < kNumTimestampsOffset) {
+      expected_error = "Unable to read delta time largest observed.";
+    } else if (i < kNumMissingPacketOffset) {
+      expected_error = "Unable to read num received packets.";
+    } else if (i < kMissingPacketsOffset) {
+      expected_error = "Unable to read num missing packet ranges.";
+    } else if (i < kMissingPacketsRange) {
+      expected_error = "Unable to read missing sequence number delta.";
+    } else if (i < kRevivedPacketsLength) {
+      expected_error = "Unable to read missing sequence number range.";
+    } else {
+      expected_error = "Unable to read num revived packets.";
+    }
+    CheckProcessingFails(
+        packet,
+        i + GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
+                                PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP),
+        expected_error, QUIC_INVALID_ACK_DATA);
+  }
+}
+
+TEST_P(QuicFramerTest, AckFrameRevivedPackets) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
     // connection_id
     0x10, 0x32, 0x54, 0x76,
     0x98, 0xBA, 0xDC, 0xFE,
     // packet sequence number
     0xA8, 0x9A, 0x78, 0x56,
     0x34, 0x12,
     // private flags (entropy)
     0x01,
 
     // frame type (ack frame)
     // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
     0x6C,
     // entropy hash of all received packets.
     0xBA,
     // largest observed packet sequence number
     0xBF, 0x9A, 0x78, 0x56,
     0x34, 0x12,
     // Zero delta time.
     0x0, 0x0,
+    // num received packets.
+    0x00,
     // num missing packets
     0x01,
     // missing packet delta
     0x01,
     // 0 more missing packets in range.
     0x00,
     // Number of revived packets.
+    0x01,
+    // Revived packet sequence number.
+    0xBE, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // Number of revived packets.
     0x00,
   };
 
   QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
   EXPECT_TRUE(framer_.ProcessPacket(encrypted));
 
   EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(0u, visitor_.stream_frames_.size());
   ASSERT_EQ(1u, visitor_.ack_frames_.size());
   const QuicAckFrame& frame = *visitor_.ack_frames_[0];
   EXPECT_EQ(0xBA, frame.entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x0123456789ABF), frame.largest_observed);
   ASSERT_EQ(1u, frame.missing_packets.size());
   SequenceNumberSet::const_iterator missing_iter =
       frame.missing_packets.begin();
   EXPECT_EQ(GG_UINT64_C(0x0123456789ABE), *missing_iter);
 
   const size_t kReceivedEntropyOffset = kQuicFrameTypeSize;
   const size_t kLargestObservedOffset = kReceivedEntropyOffset +
       kQuicEntropyHashSize;
   const size_t kMissingDeltaTimeOffset = kLargestObservedOffset +
       PACKET_6BYTE_SEQUENCE_NUMBER;
-  const size_t kNumMissingPacketOffset = kMissingDeltaTimeOffset +
+  const size_t kNumTimestampsOffset = kMissingDeltaTimeOffset +
       kQuicDeltaTimeLargestObservedSize;
+  const size_t kNumMissingPacketOffset = kNumTimestampsOffset +
+      kQuicNumTimestampsSize;
   const size_t kMissingPacketsOffset = kNumMissingPacketOffset +
       kNumberOfNackRangesSize;
   const size_t kMissingPacketsRange = kMissingPacketsOffset +
       PACKET_1BYTE_SEQUENCE_NUMBER;
   const size_t kRevivedPacketsLength = kMissingPacketsRange +
       PACKET_1BYTE_SEQUENCE_NUMBER;
-  // Now test framing boundaries
-  const size_t ack_frame_size = kRevivedPacketsLength +
+  const size_t kRevivedPacketSequenceNumberLength = kRevivedPacketsLength +
       PACKET_1BYTE_SEQUENCE_NUMBER;
+  // Now test framing boundaries.
+  const size_t ack_frame_size = kRevivedPacketSequenceNumberLength +
+      PACKET_6BYTE_SEQUENCE_NUMBER;
   for (size_t i = kQuicFrameTypeSize; i < ack_frame_size; ++i) {
     string expected_error;
-    if (i < kLargestObservedOffset) {
+    if (i < kReceivedEntropyOffset) {
+      expected_error = "Unable to read least unacked delta.";
+    } else if (i < kLargestObservedOffset) {
       expected_error = "Unable to read entropy hash for received packets.";
     } else if (i < kMissingDeltaTimeOffset) {
       expected_error = "Unable to read largest observed.";
+    } else if (i < kNumTimestampsOffset) {
+      expected_error = "Unable to read delta time largest observed.";
     } else if (i < kNumMissingPacketOffset) {
-      expected_error = "Unable to read delta time largest observed.";
+      expected_error = "Unable to read num received packets.";
     } else if (i < kMissingPacketsOffset) {
       expected_error = "Unable to read num missing packet ranges.";
     } else if (i < kMissingPacketsRange) {
       expected_error = "Unable to read missing sequence number delta.";
     } else if (i < kRevivedPacketsLength) {
       expected_error = "Unable to read missing sequence number range.";
+    } else if (i < kRevivedPacketSequenceNumberLength) {
+      expected_error = "Unable to read num revived packets.";
     } else {
-      expected_error = "Unable to read num revived packets.";
+      expected_error = "Unable to read revived packet.";
     }
     CheckProcessingFails(
         packet,
         i + GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
                                 PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP),
         expected_error, QUIC_INVALID_ACK_DATA);
   }
 }
 
-TEST_P(QuicFramerTest, AckFrameRevivedPackets) {
+TEST_P(QuicFramerTest, AckFrameRevivedPacketsv22) {
+  if (version_ > QUIC_VERSION_22) {
+    return;
+  }
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
     0x3C,
     // connection_id
     0x10, 0x32, 0x54, 0x76,
     0x98, 0xBA, 0xDC, 0xFE,
     // packet sequence number
     0xA8, 0x9A, 0x78, 0x56,
     0x34, 0x12,
     // private flags (entropy)
@@ skipping 13 matching lines @@
     0x01,
     // missing packet delta
     0x01,
     // 0 more missing packets in range.
     0x00,
     // Number of revived packets.
     0x01,
     // Revived packet sequence number.
     0xBE, 0x9A, 0x78, 0x56,
     0x34, 0x12,
+    // Number of revived packets.
+    0x00,
   };
 
   QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
   EXPECT_TRUE(framer_.ProcessPacket(encrypted));
 
   EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(0u, visitor_.stream_frames_.size());
@@ skipping 14 matching lines @@
   const size_t kNumMissingPacketOffset = kMissingDeltaTimeOffset +
       kQuicDeltaTimeLargestObservedSize;
   const size_t kMissingPacketsOffset = kNumMissingPacketOffset +
       kNumberOfNackRangesSize;
   const size_t kMissingPacketsRange = kMissingPacketsOffset +
       PACKET_1BYTE_SEQUENCE_NUMBER;
   const size_t kRevivedPacketsLength = kMissingPacketsRange +
       PACKET_1BYTE_SEQUENCE_NUMBER;
   const size_t kRevivedPacketSequenceNumberLength = kRevivedPacketsLength +
       PACKET_1BYTE_SEQUENCE_NUMBER;
-  // Now test framing boundaries
+  // Now test framing boundaries.
   const size_t ack_frame_size = kRevivedPacketSequenceNumberLength +
       PACKET_6BYTE_SEQUENCE_NUMBER;
   for (size_t i = kQuicFrameTypeSize; i < ack_frame_size; ++i) {
     string expected_error;
     if (i < kReceivedEntropyOffset) {
       expected_error = "Unable to read least unacked delta.";
     } else if (i < kLargestObservedOffset) {
       expected_error = "Unable to read entropy hash for received packets.";
     } else if (i < kMissingDeltaTimeOffset) {
       expected_error = "Unable to read largest observed.";
@@ skipping 11 matching lines @@
       expected_error = "Unable to read revived packet.";
     }
     CheckProcessingFails(
         packet,
         i + GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
                                 PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP),
         expected_error, QUIC_INVALID_ACK_DATA);
   }
 }
 
-TEST_P(QuicFramerTest, AckFrameNoNacks) {
+TEST_P(QuicFramerTest, AckFrameNoNacksv22) {
+  if (version_ > QUIC_VERSION_22) {
+    return;
+  }
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
     0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (no nacks, not truncated, 6 byte largest observed, 1 byte delta)
+    0x4C,
+    // entropy hash of all received packets.
+    0xBA,
+    // largest observed packet sequence number
+    0xBF, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // Zero delta time.
+    0x0, 0x0,
+  };
+
+  QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
+  EXPECT_TRUE(framer_.ProcessPacket(encrypted));
+
+  EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
+  ASSERT_TRUE(visitor_.header_.get());
+  EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
+
+  EXPECT_EQ(0u, visitor_.stream_frames_.size());
+  ASSERT_EQ(1u, visitor_.ack_frames_.size());
+  QuicAckFrame* frame = visitor_.ack_frames_[0];
+  EXPECT_EQ(0xBA, frame->entropy_hash);
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABF), frame->largest_observed);
+  ASSERT_EQ(0u, frame->missing_packets.size());
+
+  // Verify that the packet re-serializes identically.
+  QuicFrames frames;
+  frames.push_back(QuicFrame(frame));
+  scoped_ptr<QuicPacket> data(BuildDataPacket(*visitor_.header_, frames));
+  ASSERT_TRUE(data != NULL);
+
+  test::CompareCharArraysWithHexError("constructed packet",
+                                      data->data(), data->length(),
+                                      AsChars(packet), arraysize(packet));
+}
+
+TEST_P(QuicFramerTest, AckFrameNoNacks) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
     // connection_id
     0x10, 0x32, 0x54, 0x76,
     0x98, 0xBA, 0xDC, 0xFE,
     // packet sequence number
     0xA8, 0x9A, 0x78, 0x56,
     0x34, 0x12,
     // private flags (entropy)
     0x01,
 
     // frame type (ack frame)
     // (no nacks, not truncated, 6 byte largest observed, 1 byte delta)
     0x4C,
     // entropy hash of all received packets.
     0xBA,
     // largest observed packet sequence number
     0xBF, 0x9A, 0x78, 0x56,
     0x34, 0x12,
     // Zero delta time.
     0x0, 0x0,
+    // Number of received packets.
+    0x00,
   };
 
   QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
   EXPECT_TRUE(framer_.ProcessPacket(encrypted));
 
   EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(0u, visitor_.stream_frames_.size());
   ASSERT_EQ(1u, visitor_.ack_frames_.size());
   QuicAckFrame* frame = visitor_.ack_frames_[0];
   EXPECT_EQ(0xBA, frame->entropy_hash);
   EXPECT_EQ(GG_UINT64_C(0x0123456789ABF), frame->largest_observed);
   ASSERT_EQ(0u, frame->missing_packets.size());
 
   // Verify that the packet re-serializes identically.
   QuicFrames frames;
   frames.push_back(QuicFrame(frame));
   scoped_ptr<QuicPacket> data(BuildDataPacket(*visitor_.header_, frames));
   ASSERT_TRUE(data != NULL);
 
   test::CompareCharArraysWithHexError("constructed packet",
                                       data->data(), data->length(),
                                       AsChars(packet), arraysize(packet));
 }
 
+TEST_P(QuicFramerTest, AckFrame500Nacksv22) {
+  if (version_ > QUIC_VERSION_22) {
+    return;
+  }
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
+    0x6C,
+    // entropy hash of all received packets.
+    0xBA,
+    // largest observed packet sequence number
+    0xBF, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // Zero delta time.
+    0x0, 0x0,
+    // num missing packet ranges
+    0x02,
+    // missing packet delta
+    0x01,
+    // 243 more missing packets in range.
+    // The ranges are listed in this order so the re-constructed packet matches.
+    0xF3,
+    // No gap between ranges
+    0x00,
+    // 255 more missing packets in range.
+    0xFF,
+    // No revived packets.
+    0x00,
+  };
+
+  QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
+  EXPECT_TRUE(framer_.ProcessPacket(encrypted));
+
+  EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
+  ASSERT_TRUE(visitor_.header_.get());
+  EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
+
+  EXPECT_EQ(0u, visitor_.stream_frames_.size());
+  ASSERT_EQ(1u, visitor_.ack_frames_.size());
+  QuicAckFrame* frame = visitor_.ack_frames_[0];
+  EXPECT_EQ(0xBA, frame->entropy_hash);
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABF), frame->largest_observed);
+  EXPECT_EQ(0u, frame->revived_packets.size());
+  ASSERT_EQ(500u, frame->missing_packets.size());
+  SequenceNumberSet::const_iterator first_missing_iter =
+      frame->missing_packets.begin();
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABE) - 499, *first_missing_iter);
+  SequenceNumberSet::const_reverse_iterator last_missing_iter =
+      frame->missing_packets.rbegin();
+  EXPECT_EQ(GG_UINT64_C(0x0123456789ABE), *last_missing_iter);
+
+  // Verify that the packet re-serializes identically.
+  QuicFrames frames;
+  frames.push_back(QuicFrame(frame));
+  scoped_ptr<QuicPacket> data(BuildDataPacket(*visitor_.header_, frames));
+  ASSERT_TRUE(data != NULL);
+
+  test::CompareCharArraysWithHexError("constructed packet",
+                                      data->data(), data->length(),
+                                      AsChars(packet), arraysize(packet));
+}
+
 TEST_P(QuicFramerTest, AckFrame500Nacks) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
     0x3C,
     // connection_id
     0x10, 0x32, 0x54, 0x76,
     0x98, 0xBA, 0xDC, 0xFE,
     // packet sequence number
     0xA8, 0x9A, 0x78, 0x56,
     0x34, 0x12,
     // private flags (entropy)
     0x01,
 
     // frame type (ack frame)
     // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
     0x6C,
     // entropy hash of all received packets.
     0xBA,
     // largest observed packet sequence number
     0xBF, 0x9A, 0x78, 0x56,
     0x34, 0x12,
     // Zero delta time.
     0x0, 0x0,
+    // No received packets.
+    0x00,
     // num missing packet ranges
     0x02,
     // missing packet delta
     0x01,
     // 243 more missing packets in range.
     // The ranges are listed in this order so the re-constructed packet matches.
     0xF3,
     // No gap between ranges
     0x00,
     // 255 more missing packets in range.
@@ skipping 62 matching lines @@
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(0u, visitor_.stream_frames_.size());
   ASSERT_EQ(1u, visitor_.congestion_feedback_frames_.size());
   const QuicCongestionFeedbackFrame& frame =
       *visitor_.congestion_feedback_frames_[0];
   ASSERT_EQ(kTCP, frame.type);
   EXPECT_EQ(0x4030u, frame.tcp.receive_window);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = kQuicFrameTypeSize; i < 4; ++i) {
     string expected_error;
     if (i < 2) {
       expected_error = "Unable to read congestion feedback type.";
     } else if (i < 4) {
       expected_error = "Unable to read receive window.";
     }
     CheckProcessingFails(
         packet,
         i + GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
@@ skipping 121 matching lines @@
   EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(GG_UINT64_C(0x01020304), visitor_.rst_stream_frame_.stream_id);
   EXPECT_EQ(0x01, visitor_.rst_stream_frame_.error_code);
   EXPECT_EQ("because I can", visitor_.rst_stream_frame_.error_details);
   EXPECT_EQ(GG_UINT64_C(0x0807060504030201),
             visitor_.rst_stream_frame_.byte_offset);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = kQuicFrameTypeSize;
        i < QuicFramer::GetMinRstStreamFrameSize(); ++i) {
     string expected_error;
     if (i < kQuicFrameTypeSize + kQuicMaxStreamIdSize) {
       expected_error = "Unable to read stream_id.";
     } else if (i < kQuicFrameTypeSize + kQuicMaxStreamIdSize +
                        + kQuicMaxStreamOffsetSize) {
       expected_error = "Unable to read rst stream sent byte offset.";
     } else if (i < kQuicFrameTypeSize + kQuicMaxStreamIdSize +
                        + kQuicMaxStreamOffsetSize + kQuicErrorCodeSize) {
@@ skipping 43 matching lines @@
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(0u, visitor_.stream_frames_.size());
 
   EXPECT_EQ(0x11, visitor_.connection_close_frame_.error_code);
   EXPECT_EQ("because I can", visitor_.connection_close_frame_.error_details);
 
   ASSERT_EQ(0u, visitor_.ack_frames_.size());
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = kQuicFrameTypeSize;
        i < QuicFramer::GetMinConnectionCloseFrameSize(); ++i) {
     string expected_error;
     if (i < kQuicFrameTypeSize + kQuicErrorCodeSize) {
       expected_error = "Unable to read connection close error code.";
     } else {
       expected_error = "Unable to read connection close error details.";
     }
     CheckProcessingFails(
         packet,
@@ skipping 37 matching lines @@
   EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(GG_UINT64_C(0x01020304),
             visitor_.goaway_frame_.last_good_stream_id);
   EXPECT_EQ(0x9, visitor_.goaway_frame_.error_code);
   EXPECT_EQ("because I can", visitor_.goaway_frame_.reason_phrase);
 
   const size_t reason_size = arraysize("because I can") - 1;
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = kQuicFrameTypeSize;
        i < QuicFramer::GetMinGoAwayFrameSize() + reason_size; ++i) {
     string expected_error;
     if (i < kQuicFrameTypeSize + kQuicErrorCodeSize) {
       expected_error = "Unable to read go away error code.";
     } else if (i < kQuicFrameTypeSize + kQuicErrorCodeSize +
                kQuicMaxStreamIdSize) {
       expected_error = "Unable to read last good stream id.";
     } else {
       expected_error = "Unable to read goaway reason.";
@@ skipping 34 matching lines @@
 
   EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(GG_UINT64_C(0x01020304),
             visitor_.window_update_frame_.stream_id);
   EXPECT_EQ(GG_UINT64_C(0x0c0b0a0908070605),
             visitor_.window_update_frame_.byte_offset);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = kQuicFrameTypeSize;
        i < QuicFramer::GetWindowUpdateFrameSize(); ++i) {
     string expected_error;
     if (i < kQuicFrameTypeSize + kQuicMaxStreamIdSize) {
       expected_error = "Unable to read stream_id.";
     } else {
       expected_error = "Unable to read window byte_offset.";
     }
     CheckProcessingFails(
         packet,
@@ skipping 26 matching lines @@
 
   EXPECT_TRUE(framer_.ProcessPacket(encrypted));
 
   EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
   ASSERT_TRUE(visitor_.header_.get());
   EXPECT_TRUE(CheckDecryption(encrypted, !kIncludeVersion));
 
   EXPECT_EQ(GG_UINT64_C(0x01020304),
             visitor_.blocked_frame_.stream_id);
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = kQuicFrameTypeSize; i < QuicFramer::GetBlockedFrameSize();
        ++i) {
     string expected_error = "Unable to read stream_id.";
     CheckProcessingFails(
         packet,
         i + GetPacketHeaderSize(PACKET_8BYTE_CONNECTION_ID, !kIncludeVersion,
                                 PACKET_6BYTE_SEQUENCE_NUMBER, NOT_IN_FEC_GROUP),
         expected_error, QUIC_INVALID_BLOCKED_DATA);
   }
 }
@@ skipping 66 matching lines @@
             visitor_.public_reset_packet_->public_header.connection_id);
   EXPECT_TRUE(visitor_.public_reset_packet_->public_header.reset_flag);
   EXPECT_FALSE(visitor_.public_reset_packet_->public_header.version_flag);
   EXPECT_EQ(GG_UINT64_C(0xABCDEF0123456789),
             visitor_.public_reset_packet_->nonce_proof);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.public_reset_packet_->rejected_sequence_number);
   EXPECT_TRUE(
       visitor_.public_reset_packet_->client_address.address().empty());
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0; i < arraysize(packet); ++i) {
     string expected_error;
     DVLOG(1) << "iteration: " << i;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
       CheckProcessingFails(packet, i, expected_error,
                            QUIC_INVALID_PACKET_HEADER);
     } else if (i < kPublicResetPacketMessageTagOffset) {
       expected_error = "Unable to read ConnectionId.";
       CheckProcessingFails(packet, i, expected_error,
@@ skipping 85 matching lines @@
   EXPECT_FALSE(visitor_.public_reset_packet_->public_header.version_flag);
   EXPECT_EQ(GG_UINT64_C(0xABCDEF0123456789),
             visitor_.public_reset_packet_->nonce_proof);
   EXPECT_EQ(GG_UINT64_C(0x123456789ABC),
             visitor_.public_reset_packet_->rejected_sequence_number);
   EXPECT_EQ("4.31.198.44",
             IPAddressToString(visitor_.public_reset_packet_->
                 client_address.address()));
   EXPECT_EQ(443, visitor_.public_reset_packet_->client_address.port());
 
-  // Now test framing boundaries
+  // Now test framing boundaries.
   for (size_t i = 0; i < arraysize(packet); ++i) {
     string expected_error;
     DVLOG(1) << "iteration: " << i;
     if (i < kConnectionIdOffset) {
       expected_error = "Unable to read public flags.";
       CheckProcessingFails(packet, i, expected_error,
                            QUIC_INVALID_PACKET_HEADER);
     } else if (i < kPublicResetPacketMessageTagOffset) {
       expected_error = "Unable to read ConnectionId.";
       CheckProcessingFails(packet, i, expected_error,
@@ skipping 441 matching lines @@
     'Q', '0', GetQuicVersionDigitTens(), GetQuicVersionDigitOnes(),
   };
 
   QuicVersionVector versions;
   versions.push_back(GetParam());
   scoped_ptr<QuicEncryptedPacket> data(
       framer_.BuildVersionNegotiationPacket(header, versions));
 
   test::CompareCharArraysWithHexError("constructed packet",
                                       data->data(), data->length(),
+                                      AsChars(packet), arraysize(packet));
+}
+
+TEST_P(QuicFramerTest, BuildAckFramePacketv22) {
+  if (version_ > QUIC_VERSION_22) {
+    return;
+  }
+  QuicPacketHeader header;
+  header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
+  header.public_header.reset_flag = false;
+  header.public_header.version_flag = false;
+  header.fec_flag = false;
+  header.entropy_flag = true;
+  header.packet_sequence_number = GG_UINT64_C(0x770123456789AA8);
+  header.fec_group = 0;
+
+  QuicAckFrame ack_frame;
+  ack_frame.entropy_hash = 0x43;
+  ack_frame.largest_observed = GG_UINT64_C(0x770123456789ABF);
+  ack_frame.delta_time_largest_observed = QuicTime::Delta::Zero();
+  ack_frame.missing_packets.insert(
+      GG_UINT64_C(0x770123456789ABE));
+
+  QuicFrames frames;
+  frames.push_back(QuicFrame(&ack_frame));
+
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
+    0x6C,
+    // entropy hash of all received packets.
+    0x43,
+    // largest observed packet sequence number
+    0xBF, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // Zero delta time.
+    0x0, 0x0,
+    // num missing packet ranges
+    0x01,
+    // missing packet delta
+    0x01,
+    // 0 more missing packets in range.
+    0x00,
+    // 0 revived packets.
+    0x00,
+  };
+
+  scoped_ptr<QuicPacket> data(BuildDataPacket(header, frames));
+  ASSERT_TRUE(data != NULL);
+
+  test::CompareCharArraysWithHexError("constructed packet",
+                                      data->data(), data->length(),
                                       AsChars(packet), arraysize(packet));
 }
 
 TEST_P(QuicFramerTest, BuildAckFramePacket) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
   QuicPacketHeader header;
   header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
   header.public_header.reset_flag = false;
   header.public_header.version_flag = false;
   header.fec_flag = false;
   header.entropy_flag = true;
   header.packet_sequence_number = GG_UINT64_C(0x770123456789AA8);
   header.fec_group = 0;
 
   QuicAckFrame ack_frame;
@@ skipping 21 matching lines @@
     // frame type (ack frame)
     // (has nacks, not truncated, 6 byte largest observed, 1 byte delta)
     0x6C,
     // entropy hash of all received packets.
     0x43,
     // largest observed packet sequence number
     0xBF, 0x9A, 0x78, 0x56,
     0x34, 0x12,
     // Zero delta time.
     0x0, 0x0,
+    // num received packets.
+    0x00,
     // num missing packet ranges
     0x01,
     // missing packet delta
     0x01,
     // 0 more missing packets in range.
     0x00,
     // 0 revived packets.
     0x00,
   };
 
   scoped_ptr<QuicPacket> data(BuildDataPacket(header, frames));
   ASSERT_TRUE(data != NULL);
 
   test::CompareCharArraysWithHexError("constructed packet",
                                       data->data(), data->length(),
                                       AsChars(packet), arraysize(packet));
 }
 
 // TODO(jri): Add test for tuncated packets in which the original ack frame had
 // revived packets. (In both the large and small packet cases below).
-TEST_P(QuicFramerTest, BuildTruncatedAckFrameLargePacket) {
+
+TEST_P(QuicFramerTest, BuildTruncatedAckFrameLargePacketv22) {
+  if (version_ > QUIC_VERSION_22) {
+    return;
+  }
   QuicPacketHeader header;
   header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
   header.public_header.reset_flag = false;
+  header.public_header.version_flag = false;
+  header.fec_flag = false;
+  header.entropy_flag = true;
+  header.packet_sequence_number = GG_UINT64_C(0x770123456789AA8);
+  header.fec_group = 0;
+
+  QuicAckFrame ack_frame;
+  // This entropy hash is different from what shows up in the packet below,
+  // since entropy is recomputed by the framer on ack truncation (by
+  // TestEntropyCalculator for this test.)
+  ack_frame.entropy_hash = 0x43;
+  ack_frame.largest_observed = 2 * 300;
+  ack_frame.delta_time_largest_observed = QuicTime::Delta::Zero();
+  for (size_t i = 1; i < 2 * 300; i += 2) {
+    ack_frame.missing_packets.insert(i);
+  }
+
+  QuicFrames frames;
+  frames.push_back(QuicFrame(&ack_frame));
+
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (has nacks, is truncated, 2 byte largest observed, 1 byte delta)
+    0x74,
+    // entropy hash of all received packets, set to 1 by TestEntropyCalculator
+    // since ack is truncated.
+    0x01,
+    // 2-byte largest observed packet sequence number.
+    // Expected to be 510 (0x1FE), since only 255 nack ranges can fit.
+    0xFE, 0x01,
+    // Zero delta time.
+    0x0, 0x0,
+    // num missing packet ranges (limited to 255 by size of this field).
+    0xFF,
+    // {missing packet delta, further missing packets in range}
+    // 6 nack ranges x 42 + 3 nack ranges
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+
+    // 0 revived packets.
+    0x00,
+  };
+
+  scoped_ptr<QuicPacket> data(
+      framer_.BuildDataPacket(header, frames, kMaxPacketSize).packet);
+  ASSERT_TRUE(data != NULL);
+
+  test::CompareCharArraysWithHexError("constructed packet",
+                                      data->data(), data->length(),
+                                      AsChars(packet), arraysize(packet));
+}
+
+TEST_P(QuicFramerTest, BuildTruncatedAckFrameLargePacket) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
+  QuicPacketHeader header;
+  header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
+  header.public_header.reset_flag = false;
   header.public_header.version_flag = false;
   header.fec_flag = false;
   header.entropy_flag = true;
   header.packet_sequence_number = GG_UINT64_C(0x770123456789AA8);
   header.fec_group = 0;
 
   QuicAckFrame ack_frame;
   // This entropy hash is different from what shows up in the packet below,
   // since entropy is recomputed by the framer on ack truncation (by
   // TestEntropyCalculator for this test.)
@@ skipping 89 matching lines @@
   scoped_ptr<QuicPacket> data(
       framer_.BuildDataPacket(header, frames, kMaxPacketSize).packet);
   ASSERT_TRUE(data != NULL);
 
   test::CompareCharArraysWithHexError("constructed packet",
                                       data->data(), data->length(),
                                       AsChars(packet), arraysize(packet));
 }
 
 
-TEST_P(QuicFramerTest, BuildTruncatedAckFrameSmallPacket) {
+TEST_P(QuicFramerTest, BuildTruncatedAckFrameSmallPacketv22) {
+  if (version_ > QUIC_VERSION_22) {
+    return;
+  }
   QuicPacketHeader header;
   header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
   header.public_header.reset_flag = false;
+  header.public_header.version_flag = false;
+  header.fec_flag = false;
+  header.entropy_flag = true;
+  header.packet_sequence_number = GG_UINT64_C(0x770123456789AA8);
+  header.fec_group = 0;
+
+  QuicAckFrame ack_frame;
+  // This entropy hash is different from what shows up in the packet below,
+  // since entropy is recomputed by the framer on ack truncation (by
+  // TestEntropyCalculator for this test.)
+  ack_frame.entropy_hash = 0x43;
+  ack_frame.largest_observed = 2 * 300;
+  ack_frame.delta_time_largest_observed = QuicTime::Delta::Zero();
+  for (size_t i = 1; i < 2 * 300; i += 2) {
+    ack_frame.missing_packets.insert(i);
+  }
+
+  QuicFrames frames;
+  frames.push_back(QuicFrame(&ack_frame));
+
+  unsigned char packet[] = {
+    // public flags (8 byte connection_id)
+    0x3C,
+    // connection_id
+    0x10, 0x32, 0x54, 0x76,
+    0x98, 0xBA, 0xDC, 0xFE,
+    // packet sequence number
+    0xA8, 0x9A, 0x78, 0x56,
+    0x34, 0x12,
+    // private flags (entropy)
+    0x01,
+
+    // frame type (ack frame)
+    // (has nacks, is truncated, 2 byte largest observed, 1 byte delta)
+    0x74,
+    // entropy hash of all received packets, set to 1 by TestEntropyCalculator
+    // since ack is truncated.
+    0x01,
+    // 2-byte largest observed packet sequence number.
+    // Expected to be 12 (0x0C), since only 6 nack ranges can fit.
+    0x0C, 0x00,
+    // Zero delta time.
+    0x0, 0x0,
+    // num missing packet ranges (limited to 6 by packet size of 37).
+    0x06,
+    // {missing packet delta, further missing packets in range}
+    // 6 nack ranges
+    0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00, 0x01, 0x00,
+    // 0 revived packets.
+    0x00,
+  };
+
+  scoped_ptr<QuicPacket> data(
+      framer_.BuildDataPacket(header, frames, 37u).packet);
+  ASSERT_TRUE(data != NULL);
+  // Expect 1 byte unused since at least 2 bytes are needed to fit more nacks.
+  EXPECT_EQ(36u, data->length());
+  test::CompareCharArraysWithHexError("constructed packet",
+                                      data->data(), data->length(),
+                                      AsChars(packet), arraysize(packet));
+}
+
+TEST_P(QuicFramerTest, BuildTruncatedAckFrameSmallPacket) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
+  QuicPacketHeader header;
+  header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
+  header.public_header.reset_flag = false;
   header.public_header.version_flag = false;
   header.fec_flag = false;
   header.entropy_flag = true;
   header.packet_sequence_number = GG_UINT64_C(0x770123456789AA8);
   header.fec_group = 0;
 
   QuicAckFrame ack_frame;
   // This entropy hash is different from what shows up in the packet below,
   // since entropy is recomputed by the framer on ack truncation (by
   // TestEntropyCalculator for this test.)
@@ skipping 145 matching lines @@
   header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
   header.public_header.reset_flag = false;
   header.public_header.version_flag = false;
   header.fec_flag = false;
   header.entropy_flag = false;
   header.packet_sequence_number = GG_UINT64_C(0x123456789ABC);
   header.fec_group = 0;
 
   QuicCongestionFeedbackFrame congestion_feedback_frame;
   congestion_feedback_frame.type =
-      static_cast<CongestionFeedbackType>(kTimestamp + 1);
+      static_cast<CongestionFeedbackType>(kTCP + 1);
 
   QuicFrames frames;
   frames.push_back(QuicFrame(&congestion_feedback_frame));
 
   scoped_ptr<QuicPacket> data;
   EXPECT_DFATAL(
       data.reset(BuildDataPacket(header, frames)),
       "AppendCongestionFeedbackFrame failed");
   ASSERT_TRUE(data == NULL);
 }
@@ skipping 536 matching lines @@
   EXPECT_EQ(510u, processed_ack_frame.largest_observed);
   ASSERT_EQ(255u, processed_ack_frame.missing_packets.size());
   SequenceNumberSet::const_iterator missing_iter =
       processed_ack_frame.missing_packets.begin();
   EXPECT_EQ(1u, *missing_iter);
   SequenceNumberSet::const_reverse_iterator last_missing_iter =
       processed_ack_frame.missing_packets.rbegin();
   EXPECT_EQ(509u, *last_missing_iter);
 }
 
-TEST_P(QuicFramerTest, AckTruncationSmallPacket) {
+TEST_P(QuicFramerTest, AckTruncationSmallPacketv22) {
+  if (version_ > QUIC_VERSION_22) {
+    return;
+  }
   QuicPacketHeader header;
   header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
   header.public_header.reset_flag = false;
+  header.public_header.version_flag = false;
+  header.fec_flag = false;
+  header.entropy_flag = false;
+  header.packet_sequence_number = GG_UINT64_C(0x123456789ABC);
+  header.fec_group = 0;
+
+  // Create a packet with just the ack.
+  QuicAckFrame ack_frame = MakeAckFrameWithNackRanges(300, 0u);
+  QuicFrame frame;
+  frame.type = ACK_FRAME;
+  frame.ack_frame = &ack_frame;
+  QuicFrames frames;
+  frames.push_back(frame);
+
+  // Build an ack packet with truncation due to limit in number of nack ranges.
+  scoped_ptr<QuicPacket> raw_ack_packet(
+      framer_.BuildDataPacket(header, frames, 500).packet);
+  ASSERT_TRUE(raw_ack_packet != NULL);
+  scoped_ptr<QuicEncryptedPacket> ack_packet(
+      framer_.EncryptPacket(ENCRYPTION_NONE, header.packet_sequence_number,
+                            *raw_ack_packet));
+  // Now make sure we can turn our ack packet back into an ack frame.
+  ASSERT_TRUE(framer_.ProcessPacket(*ack_packet));
+  ASSERT_EQ(1u, visitor_.ack_frames_.size());
+  QuicAckFrame& processed_ack_frame = *visitor_.ack_frames_[0];
+  EXPECT_TRUE(processed_ack_frame.is_truncated);
+  EXPECT_EQ(476u, processed_ack_frame.largest_observed);
+  ASSERT_EQ(238u, processed_ack_frame.missing_packets.size());
+  SequenceNumberSet::const_iterator missing_iter =
+      processed_ack_frame.missing_packets.begin();
+  EXPECT_EQ(1u, *missing_iter);
+  SequenceNumberSet::const_reverse_iterator last_missing_iter =
+      processed_ack_frame.missing_packets.rbegin();
+  EXPECT_EQ(475u, *last_missing_iter);
+}
+
+
+TEST_P(QuicFramerTest, AckTruncationSmallPacket) {
+  if (version_ <= QUIC_VERSION_22) {
+    return;
+  }
+  QuicPacketHeader header;
+  header.public_header.connection_id = GG_UINT64_C(0xFEDCBA9876543210);
+  header.public_header.reset_flag = false;
   header.public_header.version_flag = false;
   header.fec_flag = false;
   header.entropy_flag = false;
   header.packet_sequence_number = GG_UINT64_C(0x123456789ABC);
   header.fec_group = 0;
 
   // Create a packet with just the ack.
   QuicAckFrame ack_frame = MakeAckFrameWithNackRanges(300, 0u);
   QuicFrame frame;
   frame.type = ACK_FRAME;
@@ skipping 197 matching lines @@
   EXPECT_CALL(visitor, OnPacketComplete());
   EXPECT_CALL(visitor, OnUnauthenticatedPublicHeader(_)).WillOnce(Return(true));
 
   QuicEncryptedPacket encrypted(AsChars(packet), arraysize(packet), false);
   EXPECT_TRUE(framer_.ProcessPacket(encrypted));
   EXPECT_EQ(QUIC_NO_ERROR, framer_.error());
 }
 
 }  // namespace test
 }  // namespace net