This CL adds methods to manipulate RTP header extension, particularly

content/browser/renderer_host/p2p/socket_host_unittest.cc

+// Copyright (c) 2014 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 "content/browser/renderer_host/p2p/socket_host.h"
+
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "content/browser/renderer_host/p2p/socket_host_test_utils.h"
+#include "net/base/ip_endpoint.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+// Rtp message with invalid length.
+static unsigned char kRtpMsgWithInvalidLength[] = {
+  0x94, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+  0xAA, 0xBB, 0xCC, 0XDD,  // SSRC
+  0xDD, 0xCC, 0xBB, 0xAA   // Only 1 CSRC, but CC count is 4.
+};
+
+// Rtp message with single byte header extension, invalid extension length.
+static unsigned char kRtpMessageWithInvalidExtnLength[] = {

[Solis, 2014/03/03 10:22:29]

Stick to either Msg or Message.

[Mallinath (Gone from Chromium), 2014/03/04 00:15:46]

Done.

[Mallinath (Gone from Chromium), 2014/03/04 00:15:46]

Sticking to Msg

On 2014/03/03 10:22:29, Solis wrote:

+  0x90, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+  0xBE, 0xDE, 0x0A, 0x00   // Extn length - 0x0A00
+};
+
+// Valid rtp Message with 2 byte header extension.
+static unsigned char kRtpMsgWith2ByteExtnHeader[] = {
+  0x90, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+  0xAA, 0xBB, 0xCC, 0XDD,  // SSRC
+  0x10, 0x00, 0x00, 0x01,  // 2 Byte header extension
+  0x01, 0x00, 0x00, 0x00
+};
+
+// Stun Indication message with Zero length
+static unsigned char kTurnSendIndicationMsgWithNoAttributes[] = {
+  0x00, 0x16, 0x00, 0x00,  // Zero length
+  0x21, 0x12, 0xA4, 0x42,  // magic cookie
+  '0', '1', '2', '3',      // transaction id
+  '4', '5', '6', '7',
+  '8', '9', 'a', 'b',
+};
+
+// Stun Send Indication message with invalid length in stun header.
+static unsigned char kTurnSendIndicationMsgWithInvalidLength[] = {
+  0x00, 0x16, 0xFF, 0x00,  // length of 0xFF00
+  0x21, 0x12, 0xA4, 0x42,  // magic cookie
+  '0', '1', '2', '3',      // transaction id
+  '4', '5', '6', '7',
+  '8', '9', 'a', 'b',
+};
+
+// Stun Send Indication message with no DATA attribute in message.
+static unsigned char kTurnSendIndicatinMsgWithNoDataAttribute[] = {
+  0x00, 0x16, 0x00, 0x08,  // length of
+  0x21, 0x12, 0xA4, 0x42,  // magic cookie
+  '0', '1', '2', '3',      // transaction id
+  '4', '5', '6', '7',
+  '8', '9', 'a', 'b',
+  0x00, 0x20, 0x00, 0x04,  // Mapped address.
+  0x00, 0x00, 0x00, 0x00
+};
+
+// A valid STUN indication message with a valid RTP header in data attribute
+// payload field and no extension bit set.
+static unsigned char kTurnSendIndicationMsgWithoutRtpExtension[] = {
+  0x00, 0x16, 0x00, 0x18,  // length of
+  0x21, 0x12, 0xA4, 0x42,  // magic cookie
+  '0', '1', '2', '3',      // transaction id
+  '4', '5', '6', '7',
+  '8', '9', 'a', 'b',
+  0x00, 0x20, 0x00, 0x04,  // Mapped address.
+  0x00, 0x00, 0x00, 0x00,
+  0x00, 0x13, 0x00, 0x0C,  // Data attribute.
+  0x80, 0x00, 0x00, 0x00,  // RTP packet.
+  0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+};
+
+// A valid STUN indication message with a valid RTP header and a extension
+// header.
+static unsigned char kTurnSendIndicationMsgWithAbsSendTimeExtension[] = {
+  0x00, 0x16, 0x00, 0x20,  // length of
+  0x21, 0x12, 0xA4, 0x42,  // magic cookie
+  '0', '1', '2', '3',      // transaction id
+  '4', '5', '6', '7',
+  '8', '9', 'a', 'b',
+  0x00, 0x20, 0x00, 0x04,  // Mapped address.
+  0x00, 0x00, 0x00, 0x00,
+  0x00, 0x13, 0x00, 0x14,  // Data attribute.
+  0x90, 0x00, 0x00, 0x00,  // RTP packet.
+  0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+  0xBE, 0xDE, 0x00, 0x01,
+  0x32, 0xaa, 0xbb, 0xcc,
+};
+
+// A valid TURN channel header, but not RTP packet.
+static unsigned char kTurnChannelMessageNoRtpPacket[] = {
+  0x40, 0x00, 0x00, 0x04,
+  0xaa, 0xbb, 0xcc, 0xdd,
+};
+
+// Turn ChannelMessage with zero length of payload.
+static unsigned char kTurnChannelMessageWithZeroLength[] = {
+  0x40, 0x00, 0x00, 0x00
+};
+
+// Turn ChannelMessage, wrapping a RTP packet without extension.
+static unsigned char kTurnChannelMessageWithRtpPacket[] = {
+  0x40, 0x00, 0x00, 0x0C,
+  0x80, 0x00, 0x00, 0x00,  // RTP packet.
+  0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+};
+
+// Turn ChannelMessage, wrapping a RTP packet with AbsSendTime Extension.
+static unsigned char kTurnChannelMessageWithAbsSendTimeExtension[] = {
+  0x40, 0x00, 0x00, 0x14,
+  0x90, 0x00, 0x00, 0x00,  // RTP packet.
+  0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+  0xBE, 0xDE, 0x00, 0x01,
+  0x32, 0xaa, 0xbb, 0xcc,
+};
+
+// RTP packet with single byte extension header of length 4 bytes.
+// Extension id = 3 and length = 3
+static unsigned char kRtpPacketWithAbsSendTimeExtension[] = {
+  0x90, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00,
+  0xBE, 0xDE, 0x00, 0x01,
+  0x32, 0xaa, 0xbb, 0xcc,
+};
+
+namespace content {
+
+// This test verifies parsing of all invalid raw packets.
+TEST(P2PSocketHostTest, TestInvalidRawRtpMessages) {
+  int start_pos = -1, rtp_length = -1;
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kRtpMsgWithInvalidLength),
+      sizeof(kRtpMsgWithInvalidLength),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(-1, start_pos);
+  EXPECT_EQ(-1, rtp_length);
+
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kRtpMessageWithInvalidExtnLength),
+      sizeof(kRtpMessageWithInvalidExtnLength),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(-1, start_pos);
+  EXPECT_EQ(-1, rtp_length);
+}
+
+// Verify invalid TURN send indication messages. Messages are proper STUN
+// messages with incorrect values in attributes.
+TEST(P2PSocketHostTest, TestInvalidTurnSendIndicationMessages) {
+  int start_pos = -1, rtp_length = -1;
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithNoAttributes),
+      sizeof(kTurnSendIndicationMsgWithNoAttributes),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(-1, start_pos);
+  EXPECT_EQ(-1, rtp_length);
+
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithInvalidLength),
+      sizeof(kTurnSendIndicationMsgWithInvalidLength),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(-1, start_pos);
+  EXPECT_EQ(-1, rtp_length);
+
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicatinMsgWithNoDataAttribute),
+      sizeof(kTurnSendIndicatinMsgWithNoDataAttribute),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(-1, start_pos);
+  EXPECT_EQ(-1, rtp_length);
+
+  // Initializing out params to very large value.

[Solis, 2014/03/03 10:22:29]

You should only need one test per message. Pick a default that will 1. cause
indexing to shoot off into unallocated memory if the inputs are used without
internal initialization (causing an access fault), and 2. is un unlikely result.
-1 doesn't satisfy the first criteria. INT_MAX is a better choice.

[Mallinath (Gone from Chromium), 2014/03/04 00:15:46]

Done.

+  start_pos = INT_MAX;
+  rtp_length = INT_MAX;
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithNoAttributes),
+      sizeof(kTurnSendIndicationMsgWithNoAttributes),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(INT_MAX, start_pos);
+  EXPECT_EQ(INT_MAX, rtp_length);
+
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithInvalidLength),
+      sizeof(kTurnSendIndicationMsgWithInvalidLength),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(INT_MAX, start_pos);
+  EXPECT_EQ(INT_MAX, rtp_length);
+
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicatinMsgWithNoDataAttribute),
+      sizeof(kTurnSendIndicatinMsgWithNoDataAttribute),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(INT_MAX, start_pos);
+  EXPECT_EQ(INT_MAX, rtp_length);
+}
+
+// This test verifies incorrectly formed TURN channel messages.
+TEST(P2PSocketHostTest, TestInvalidTurnChannelMessages) {
+  int start_pos = -1, rtp_length = -1;
+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnChannelMessageNoRtpPacket),
+      sizeof(kTurnChannelMessageNoRtpPacket),
+      &start_pos, &rtp_length));
+

[Solis, 2014/03/03 10:22:29]

EXPECT_EQ(-1, ...) here as well

[Mallinath (Gone from Chromium), 2014/03/04 00:15:46]

Done.

+  EXPECT_FALSE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnChannelMessageWithZeroLength),
+      sizeof(kTurnChannelMessageWithZeroLength),
+      &start_pos, &rtp_length));
+}
+
+// This test verifies parsing of a valid RTP packet which has 2byte header
+// extension instead of a 1 byte header extension.
+TEST(P2PSocketHostTest, TestValid2ByteExtnHdrRtpMessage) {
+  int start_pos = -1, rtp_length = -1;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kRtpMsgWith2ByteExtnHeader),
+      sizeof(kRtpMsgWith2ByteExtnHeader),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(20, rtp_length);
+  EXPECT_EQ(0, start_pos);
+}
+
+// This test verifies parsing of a valid RTP packet which has 1 byte header
+// AbsSendTime extension in it.
+TEST(P2PSocketHostTest, TestValidRtpPacketWithAbsSendTimeExtension) {
+  int start_pos = -1, rtp_length = -1;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kRtpPacketWithAbsSendTimeExtension),

[Solis, 2014/03/03 10:22:29]

Why is this in a separate test case here, and another one in
TestValidTurnSendIndicationMessages?

[Mallinath (Gone from Chromium), 2014/03/04 00:15:46]

It was by mistake.

On 2014/03/03 10:22:29, Solis wrote:

+      sizeof(kRtpPacketWithAbsSendTimeExtension),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(20, rtp_length);
+  EXPECT_EQ(0, start_pos);
+}
+
+// This test verifies parsing of a valid TURN Send Indication messages.
+TEST(P2PSocketHostTest, TestValidTurnSendIndicationMessages) {
+  int start_pos = -1, rtp_length = -1;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithoutRtpExtension),
+      sizeof(kTurnSendIndicationMsgWithoutRtpExtension),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(12, rtp_length);
+  EXPECT_EQ(32, start_pos);
+
+  start_pos = -1, rtp_length = -1;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithAbsSendTimeExtension),
+      sizeof(kTurnSendIndicationMsgWithAbsSendTimeExtension),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(20, rtp_length);
+  EXPECT_EQ(32, start_pos);
+
+  // Initializing out params to very large value.
+  start_pos = INT_MAX, rtp_length = INT_MAX;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithoutRtpExtension),
+      sizeof(kTurnSendIndicationMsgWithoutRtpExtension),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(12, rtp_length);
+  EXPECT_EQ(32, start_pos);
+
+  start_pos = INT_MAX, rtp_length = INT_MAX;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithAbsSendTimeExtension),
+      sizeof(kTurnSendIndicationMsgWithAbsSendTimeExtension),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(20, rtp_length);
+  EXPECT_EQ(32, start_pos);
+
+  start_pos = INT_MAX, rtp_length = INT_MAX;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kRtpPacketWithAbsSendTimeExtension),
+      sizeof(kRtpPacketWithAbsSendTimeExtension),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(20, rtp_length);
+  EXPECT_EQ(0, start_pos);
+}
+
+// This test verifies parsing of valid TURN Channel Messages.
+TEST(P2PSocketHostTest, TestValidTurnChannelMessages) {
+  int start_pos = -1, rtp_length = -1;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnChannelMessageWithRtpPacket),
+      sizeof(kTurnChannelMessageWithRtpPacket), &start_pos, &rtp_length));
+  EXPECT_EQ(12, rtp_length);
+  EXPECT_EQ(4, start_pos);
+
+  start_pos = -1, rtp_length = -1;
+  EXPECT_TRUE(packet_processing_helpers::GetRtpPacketStartPositionAndLength(
+      reinterpret_cast<char*>(kTurnChannelMessageWithAbsSendTimeExtension),
+      sizeof(kTurnChannelMessageWithAbsSendTimeExtension),
+      &start_pos, &rtp_length));
+  EXPECT_EQ(20, rtp_length);
+  EXPECT_EQ(4, start_pos);
+}
+
+// This test verifies seraching of RTP exension ID supplied as input in a

[Solis, 2014/03/03 10:22:29]

spelling
it looks to me the comment is wrong btw.

[Mallinath (Gone from Chromium), 2014/03/04 00:15:46]

Done.

+// RTP packet. If it finds it will be update the the timestamp.
+TEST(P2PSocketHostTest, TestUpdateAbsSendTimeExtensionIn2ByteHeaderExtn) {
+  EXPECT_FALSE(packet_processing_helpers::MaybeUpdateRtpAbsSendTimeExtn(
+    reinterpret_cast<char*>(kRtpMsgWith2ByteExtnHeader),
+    sizeof(kRtpMsgWith2ByteExtnHeader), 3));
+}
+
+// This test verifies updating AbsSendTime extension in a Turn Send Indication
+// message.
+TEST(P2PSocketHostTest, TestUpdateAbsSendTimeExtensionInTurnSendIndication) {
+  EXPECT_TRUE(packet_processing_helpers::MaybeUpdateRtpAbsSendTimeExtn(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithoutRtpExtension),
+      sizeof(kTurnSendIndicationMsgWithoutRtpExtension), 3));
+
+  EXPECT_TRUE(packet_processing_helpers::MaybeUpdateRtpAbsSendTimeExtn(
+      reinterpret_cast<char*>(kTurnSendIndicationMsgWithAbsSendTimeExtension),
+      sizeof(kTurnSendIndicationMsgWithAbsSendTimeExtension), 3));
+}
+
+// This test verifies updating AbsSendTime extension in a raw rtp message.
+TEST(P2PSocketHostTest, TestUpdateAbsSendTimeExtensionInRtpPacket) {
+  EXPECT_TRUE(packet_processing_helpers::MaybeUpdateRtpAbsSendTimeExtn(
+      reinterpret_cast<char*>(kRtpPacketWithAbsSendTimeExtension),
+      sizeof(kRtpPacketWithAbsSendTimeExtension), 3));
+}
+
+}  // namespace content