webrtc/modules/rtp_rtcp/source/rtcp_utility.cc

1351 lines
35 KiB
C++

/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "rtcp_utility.h"
#include <cstring> // memcpy
#include <cmath> // ceil
#include <cassert>
namespace webrtc {
RTCPUtility::RTCPCnameInformation::RTCPCnameInformation() :
length(0)
{
memset(name, 0, sizeof(name));
}
RTCPUtility::RTCPCnameInformation::~RTCPCnameInformation()
{
}
///////////
// RTCPParserV2 : currently read only
RTCPUtility::RTCPParserV2::RTCPParserV2( const WebRtc_UWord8* rtcpData,
size_t rtcpDataLength,
bool rtcpReducedSizeEnable)
:
_ptrRTCPDataBegin(rtcpData),
_RTCPReducedSizeEnable(rtcpReducedSizeEnable),
_ptrRTCPDataEnd(rtcpData + rtcpDataLength),
_validPacket(false),
_ptrRTCPData(rtcpData),
_state(State_TopLevel),
_numberOfBlocks(0),
_packetType(kRtcpNotValidCode)
{
Validate();
}
RTCPUtility::RTCPParserV2::~RTCPParserV2()
{
}
ptrdiff_t
RTCPUtility::RTCPParserV2::LengthLeft() const
{
return (_ptrRTCPDataEnd- _ptrRTCPData);
}
RTCPUtility::RTCPPacketTypes
RTCPUtility::RTCPParserV2::PacketType() const
{
return _packetType;
}
const RTCPUtility::RTCPPacket&
RTCPUtility::RTCPParserV2::Packet() const
{
return _packet;
}
RTCPUtility::RTCPPacketTypes
RTCPUtility::RTCPParserV2::Begin()
{
_ptrRTCPData = _ptrRTCPDataBegin;
return Iterate();
}
RTCPUtility::RTCPPacketTypes
RTCPUtility::RTCPParserV2::Iterate()
{
// Reset packet type
_packetType = kRtcpNotValidCode;
if (IsValid())
{
switch (_state)
{
case State_TopLevel:
IterateTopLevel();
break;
case State_ReportBlockItem:
IterateReportBlockItem();
break;
case State_SDESChunk:
IterateSDESChunk();
break;
case State_BYEItem:
IterateBYEItem();
break;
case State_RTPFB_NACKItem:
IterateNACKItem();
break;
case State_RTPFB_TMMBRItem:
IterateTMMBRItem();
break;
case State_RTPFB_TMMBNItem:
IterateTMMBNItem();
break;
case State_PSFB_SLIItem:
IterateSLIItem();
break;
case State_PSFB_RPSIItem:
IterateRPSIItem();
break;
case State_PSFB_FIRItem:
IterateFIRItem();
break;
case State_AppItem:
IterateAppItem();
break;
default:
assert(false); // Invalid state!
break;
}
}
return _packetType;
}
void
RTCPUtility::RTCPParserV2::IterateTopLevel()
{
for (;;)
{
RTCPCommonHeader header;
const bool success = RTCPParseCommonHeader(_ptrRTCPData,
_ptrRTCPDataEnd,
header);
if (!success)
{
return;
}
_ptrRTCPBlockEnd = _ptrRTCPData + header.LengthInOctets;
if (_ptrRTCPBlockEnd > _ptrRTCPDataEnd)
{
// Bad block!
return;
}
switch (header.PT)
{
case PT_SR:
{
// number of Report blocks
_numberOfBlocks = header.IC;
ParseSR();
return;
}
case PT_RR:
{
// number of Report blocks
_numberOfBlocks = header.IC;
ParseRR();
return;
}
case PT_SDES:
{
// number of SDES blocks
_numberOfBlocks = header.IC;
const bool ok = ParseSDES();
if (!ok)
{
// Nothing supported found, continue to next block!
break;
}
return;
}
case PT_BYE:
{
_numberOfBlocks = header.IC;
const bool ok = ParseBYE();
if (!ok)
{
// Nothing supported found, continue to next block!
break;
}
return;
}
case PT_RTPFB: // Fall through!
case PT_PSFB:
{
const bool ok = ParseFBCommon(header);
if (!ok)
{
// Nothing supported found, continue to next block!
break;
}
return;
}
case PT_APP:
{
const bool ok = ParseAPP(header);
if (!ok)
{
// Nothing supported found, continue to next block!
break;
}
return;
}
case PT_XR:
{
const bool ok = ParseXR();
if (!ok)
{
// Nothing supported found, continue to next block!
break;
}
return;
}
default:
// Not supported! Skip!
EndCurrentBlock();
break;
}
}
}
void
RTCPUtility::RTCPParserV2::IterateReportBlockItem()
{
const bool success = ParseReportBlockItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateSDESChunk()
{
const bool success = ParseSDESChunk();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateBYEItem()
{
const bool success = ParseBYEItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateNACKItem()
{
const bool success = ParseNACKItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateTMMBRItem()
{
const bool success = ParseTMMBRItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateTMMBNItem()
{
const bool success = ParseTMMBNItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateSLIItem()
{
const bool success = ParseSLIItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateRPSIItem()
{
const bool success = ParseRPSIItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateFIRItem()
{
const bool success = ParseFIRItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::IterateAppItem()
{
const bool success = ParseAPPItem();
if (!success)
{
Iterate();
}
}
void
RTCPUtility::RTCPParserV2::Validate()
{
if (_ptrRTCPData == NULL)
{
return; // NOT VALID
}
RTCPCommonHeader header;
const bool success = RTCPParseCommonHeader(_ptrRTCPDataBegin,
_ptrRTCPDataEnd,
header);
if (!success)
{
return; // NOT VALID!
}
// * if (!reducedSize) : first packet must be RR or SR.
//
// * The padding bit (P) should be zero for the first packet of a
// compound RTCP packet because padding should only be applied,
// if it is needed, to the last packet. (NOT CHECKED!)
//
// * The length fields of the individual RTCP packets must add up
// to the overall length of the compound RTCP packet as
// received. This is a fairly strong check. (NOT CHECKED!)
if (!_RTCPReducedSizeEnable)
{
if ((header.PT != PT_SR) && (header.PT != PT_RR))
{
return; // NOT VALID
}
}
_validPacket = true;
}
bool
RTCPUtility::RTCPParserV2::IsValid() const
{
return _validPacket;
}
void
RTCPUtility::RTCPParserV2::EndCurrentBlock()
{
_ptrRTCPData = _ptrRTCPBlockEnd;
}
bool
RTCPUtility::RTCPParseCommonHeader( const WebRtc_UWord8* ptrDataBegin,
const WebRtc_UWord8* ptrDataEnd,
RTCPCommonHeader& parsedHeader)
{
if (!ptrDataBegin || !ptrDataEnd)
{
return false;
}
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// |V=2|P| IC | PT | length |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
// Common header for all RTCP packets, 4 octets.
if ((ptrDataEnd - ptrDataBegin) < 4)
{
return false;
}
parsedHeader.V = ptrDataBegin[0] >> 6;
parsedHeader.P = ((ptrDataBegin[0] & 0x20) == 0) ? false : true;
parsedHeader.IC = ptrDataBegin[0] & 0x1f;
parsedHeader.PT = ptrDataBegin[1];
parsedHeader.LengthInOctets = (ptrDataBegin[2] << 8) + ptrDataBegin[3] + 1;
parsedHeader.LengthInOctets *= 4;
if(parsedHeader.LengthInOctets == 0)
{
return false;
}
// Check if RTP version field == 2
if (parsedHeader.V != 2)
{
return false;
}
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseRR()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 8)
{
return false;
}
_ptrRTCPData += 4; // Skip header
_packetType = kRtcpRrCode;
_packet.RR.SenderSSRC = *_ptrRTCPData++ << 24;
_packet.RR.SenderSSRC += *_ptrRTCPData++ << 16;
_packet.RR.SenderSSRC += *_ptrRTCPData++ << 8;
_packet.RR.SenderSSRC += *_ptrRTCPData++;
_packet.RR.NumberOfReportBlocks = _numberOfBlocks;
// State transition
_state = State_ReportBlockItem;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseSR()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 28)
{
EndCurrentBlock();
return false;
}
_ptrRTCPData += 4; // Skip header
_packetType = kRtcpSrCode;
_packet.SR.SenderSSRC = *_ptrRTCPData++ << 24;
_packet.SR.SenderSSRC += *_ptrRTCPData++ << 16;
_packet.SR.SenderSSRC += *_ptrRTCPData++ << 8;
_packet.SR.SenderSSRC += *_ptrRTCPData++;
_packet.SR.NTPMostSignificant = *_ptrRTCPData++ << 24;
_packet.SR.NTPMostSignificant += *_ptrRTCPData++ << 16;
_packet.SR.NTPMostSignificant += *_ptrRTCPData++ << 8;
_packet.SR.NTPMostSignificant += *_ptrRTCPData++;
_packet.SR.NTPLeastSignificant = *_ptrRTCPData++ << 24;
_packet.SR.NTPLeastSignificant += *_ptrRTCPData++ << 16;
_packet.SR.NTPLeastSignificant += *_ptrRTCPData++ << 8;
_packet.SR.NTPLeastSignificant += *_ptrRTCPData++;
_packet.SR.RTPTimestamp = *_ptrRTCPData++ << 24;
_packet.SR.RTPTimestamp += *_ptrRTCPData++ << 16;
_packet.SR.RTPTimestamp += *_ptrRTCPData++ << 8;
_packet.SR.RTPTimestamp += *_ptrRTCPData++;
_packet.SR.SenderPacketCount = *_ptrRTCPData++ << 24;
_packet.SR.SenderPacketCount += *_ptrRTCPData++ << 16;
_packet.SR.SenderPacketCount += *_ptrRTCPData++ << 8;
_packet.SR.SenderPacketCount += *_ptrRTCPData++;
_packet.SR.SenderOctetCount = *_ptrRTCPData++ << 24;
_packet.SR.SenderOctetCount += *_ptrRTCPData++ << 16;
_packet.SR.SenderOctetCount += *_ptrRTCPData++ << 8;
_packet.SR.SenderOctetCount += *_ptrRTCPData++;
_packet.SR.NumberOfReportBlocks = _numberOfBlocks;
// State transition
if(_numberOfBlocks != 0)
{
_state = State_ReportBlockItem;
}else
{
// don't go to state report block item if 0 report blocks
_state = State_TopLevel;
EndCurrentBlock();
}
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseReportBlockItem()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 24 || _numberOfBlocks <= 0)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packet.ReportBlockItem.SSRC = *_ptrRTCPData++ << 24;
_packet.ReportBlockItem.SSRC += *_ptrRTCPData++ << 16;
_packet.ReportBlockItem.SSRC += *_ptrRTCPData++ << 8;
_packet.ReportBlockItem.SSRC += *_ptrRTCPData++;
_packet.ReportBlockItem.FractionLost = *_ptrRTCPData++;
_packet.ReportBlockItem.CumulativeNumOfPacketsLost = *_ptrRTCPData++ << 16;
_packet.ReportBlockItem.CumulativeNumOfPacketsLost += *_ptrRTCPData++ << 8;
_packet.ReportBlockItem.CumulativeNumOfPacketsLost += *_ptrRTCPData++;
_packet.ReportBlockItem.ExtendedHighestSequenceNumber = *_ptrRTCPData++ << 24;
_packet.ReportBlockItem.ExtendedHighestSequenceNumber += *_ptrRTCPData++ << 16;
_packet.ReportBlockItem.ExtendedHighestSequenceNumber += *_ptrRTCPData++ << 8;
_packet.ReportBlockItem.ExtendedHighestSequenceNumber += *_ptrRTCPData++;
_packet.ReportBlockItem.Jitter = *_ptrRTCPData++ << 24;
_packet.ReportBlockItem.Jitter += *_ptrRTCPData++ << 16;
_packet.ReportBlockItem.Jitter += *_ptrRTCPData++ << 8;
_packet.ReportBlockItem.Jitter += *_ptrRTCPData++;
_packet.ReportBlockItem.LastSR = *_ptrRTCPData++ << 24;
_packet.ReportBlockItem.LastSR += *_ptrRTCPData++ << 16;
_packet.ReportBlockItem.LastSR += *_ptrRTCPData++ << 8;
_packet.ReportBlockItem.LastSR += *_ptrRTCPData++;
_packet.ReportBlockItem.DelayLastSR = *_ptrRTCPData++ << 24;
_packet.ReportBlockItem.DelayLastSR += *_ptrRTCPData++ << 16;
_packet.ReportBlockItem.DelayLastSR += *_ptrRTCPData++ << 8;
_packet.ReportBlockItem.DelayLastSR += *_ptrRTCPData++;
_numberOfBlocks--;
_packetType = kRtcpReportBlockItemCode;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseSDES()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 8)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_ptrRTCPData += 4; // Skip header
_state = State_SDESChunk;
_packetType = kRtcpSdesCode;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseSDESChunk()
{
if(_numberOfBlocks <= 0)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_numberOfBlocks--;
// Find CName item in a SDES chunk.
while (_ptrRTCPData < _ptrRTCPBlockEnd)
{
const ptrdiff_t dataLen = _ptrRTCPBlockEnd - _ptrRTCPData;
if (dataLen < 4)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
WebRtc_UWord32 SSRC = *_ptrRTCPData++ << 24;
SSRC += *_ptrRTCPData++ << 16;
SSRC += *_ptrRTCPData++ << 8;
SSRC += *_ptrRTCPData++;
const bool foundCname = ParseSDESItem();
if (foundCname)
{
_packet.CName.SenderSSRC = SSRC; // Add SSRC
return true;
}
}
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
bool
RTCPUtility::RTCPParserV2::ParseSDESItem()
{
// Find CName
// Only the CNAME item is mandatory. RFC 3550 page 46
bool foundCName = false;
size_t itemOctetsRead = 0;
while (_ptrRTCPData < _ptrRTCPBlockEnd)
{
const WebRtc_UWord8 tag = *_ptrRTCPData++;
++itemOctetsRead;
if (tag == 0)
{
// End tag! 4 oct aligned
while ((itemOctetsRead++ % 4) != 0)
{
++_ptrRTCPData;
}
return foundCName;
}
if (_ptrRTCPData < _ptrRTCPBlockEnd)
{
const WebRtc_UWord8 len = *_ptrRTCPData++;
++itemOctetsRead;
if (tag == 1)
{
// CNAME
// Sanity
if ((_ptrRTCPData + len) >= _ptrRTCPBlockEnd)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
for (unsigned int i = 0; i < len; ++i)
{
const WebRtc_UWord8 c = _ptrRTCPData[i];
if ((c < ' ') || (c > '{') || (c == '%') || (c == '\\'))
{
// Illegal char
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packet.CName.CName[i] = c;
}
_packetType = kRtcpSdesChunkCode;
_packet.CName.CNameLength = len;
foundCName = true;
}
_ptrRTCPData += len;
itemOctetsRead += len;
}
}
// No end tag found!
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
bool
RTCPUtility::RTCPParserV2::ParseBYE()
{
_ptrRTCPData += 4; // Skip header
_state = State_BYEItem;
return ParseBYEItem();
}
bool
RTCPUtility::RTCPParserV2::ParseBYEItem()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 4 || _numberOfBlocks == 0)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packetType = kRtcpByeCode;
_packet.BYE.SenderSSRC = *_ptrRTCPData++ << 24;
_packet.BYE.SenderSSRC += *_ptrRTCPData++ << 16;
_packet.BYE.SenderSSRC += *_ptrRTCPData++ << 8;
_packet.BYE.SenderSSRC += *_ptrRTCPData++;
// we can have several CSRCs attached
// sanity
if(length >= 4*_numberOfBlocks)
{
_ptrRTCPData += (_numberOfBlocks -1)*4;
}
_numberOfBlocks = 0;
return true;
}
/*
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|V=2|P|reserved | PT=XR=207 | length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SSRC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: report blocks :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
bool RTCPUtility::RTCPParserV2::ParseXR()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 8)
{
EndCurrentBlock();
return false;
}
_ptrRTCPData += 4; // Skip header
_packet.XR.OriginatorSSRC = *_ptrRTCPData++ << 24;
_packet.XR.OriginatorSSRC += *_ptrRTCPData++ << 16;
_packet.XR.OriginatorSSRC += *_ptrRTCPData++ << 8;
_packet.XR.OriginatorSSRC += *_ptrRTCPData++;
return ParseXRItem();
}
/*
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BT | type-specific | block length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: type-specific block contents :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
bool
RTCPUtility::RTCPParserV2::ParseXRItem()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 4) //
{
EndCurrentBlock();
return false;
}
WebRtc_UWord8 blockType = *_ptrRTCPData++;
WebRtc_UWord8 typeSpecific = *_ptrRTCPData++;
WebRtc_UWord16 blockLength = *_ptrRTCPData++ << 8;
blockLength = *_ptrRTCPData++;
if(blockType == 7 && typeSpecific == 0)
{
if(blockLength != 8)
{
EndCurrentBlock();
return false;
}
return ParseXRVOIPMetricItem();
}else
{
EndCurrentBlock();
return false;
}
}
/*
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BT=7 | reserved | block length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SSRC of source |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| loss rate | discard rate | burst density | gap density |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| burst duration | gap duration |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| round trip delay | end system delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| signal level | noise level | RERL | Gmin |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| R factor | ext. R factor | MOS-LQ | MOS-CQ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RX config | reserved | JB nominal |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| JB maximum | JB abs max |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
bool
RTCPUtility::RTCPParserV2::ParseXRVOIPMetricItem()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 28)
{
EndCurrentBlock();
return false;
}
_packetType = kRtcpXrVoipMetricCode;
_packet.XRVOIPMetricItem.SSRC = *_ptrRTCPData++ << 24;
_packet.XRVOIPMetricItem.SSRC += *_ptrRTCPData++ << 16;
_packet.XRVOIPMetricItem.SSRC += *_ptrRTCPData++ << 8;
_packet.XRVOIPMetricItem.SSRC += *_ptrRTCPData++;
_packet.XRVOIPMetricItem.lossRate = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.discardRate = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.burstDensity = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.gapDensity = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.burstDuration = *_ptrRTCPData++ << 8;
_packet.XRVOIPMetricItem.burstDuration += *_ptrRTCPData++;
_packet.XRVOIPMetricItem.gapDuration = *_ptrRTCPData++ << 8;
_packet.XRVOIPMetricItem.gapDuration += *_ptrRTCPData++;
_packet.XRVOIPMetricItem.roundTripDelay = *_ptrRTCPData++ << 8;
_packet.XRVOIPMetricItem.roundTripDelay += *_ptrRTCPData++;
_packet.XRVOIPMetricItem.endSystemDelay = *_ptrRTCPData++ << 8;
_packet.XRVOIPMetricItem.endSystemDelay += *_ptrRTCPData++;
_packet.XRVOIPMetricItem.signalLevel = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.noiseLevel = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.RERL = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.Gmin = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.Rfactor = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.extRfactor = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.MOSLQ = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.MOSCQ = *_ptrRTCPData++;
_packet.XRVOIPMetricItem.RXconfig = *_ptrRTCPData++;
_ptrRTCPData++; // skip reserved
_packet.XRVOIPMetricItem.JBnominal = *_ptrRTCPData++ << 8;
_packet.XRVOIPMetricItem.JBnominal += *_ptrRTCPData++;
_packet.XRVOIPMetricItem.JBmax = *_ptrRTCPData++ << 8;
_packet.XRVOIPMetricItem.JBmax += *_ptrRTCPData++;
_packet.XRVOIPMetricItem.JBabsMax = *_ptrRTCPData++ << 8;
_packet.XRVOIPMetricItem.JBabsMax += *_ptrRTCPData++;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseFBCommon(const RTCPCommonHeader& header)
{
assert((header.PT == PT_RTPFB) || (header.PT == PT_PSFB)); // Parser logic check
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 12) // 4 * 3, RFC4585 section 6.1
{
EndCurrentBlock();
return false;
}
_ptrRTCPData += 4; // Skip RTCP header
WebRtc_UWord32 senderSSRC = *_ptrRTCPData++ << 24;
senderSSRC += *_ptrRTCPData++ << 16;
senderSSRC += *_ptrRTCPData++ << 8;
senderSSRC += *_ptrRTCPData++;
WebRtc_UWord32 mediaSSRC = *_ptrRTCPData++ << 24;
mediaSSRC += *_ptrRTCPData++ << 16;
mediaSSRC += *_ptrRTCPData++ << 8;
mediaSSRC += *_ptrRTCPData++;
if (header.PT == PT_RTPFB)
{
// Transport layer feedback
switch (header.IC)
{
case 1:
{
// NACK
_packetType = kRtcpRtpfbNackCode;
_packet.NACK.SenderSSRC = senderSSRC;
_packet.NACK.MediaSSRC = mediaSSRC;
_state = State_RTPFB_NACKItem;
return true;
}
case 2:
{
// used to be ACK is this code point, which is removed
// conficts with http://tools.ietf.org/html/draft-levin-avt-rtcp-burst-00
break;
}
case 3:
{
// TMMBR
_packetType = kRtcpRtpfbTmmbrCode;
_packet.TMMBR.SenderSSRC = senderSSRC;
_packet.TMMBR.MediaSSRC = mediaSSRC;
_state = State_RTPFB_TMMBRItem;
return true;
}
case 4:
{
// TMMBN
_packetType = kRtcpRtpfbTmmbnCode;
_packet.TMMBN.SenderSSRC = senderSSRC;
_packet.TMMBN.MediaSSRC = mediaSSRC;
_state = State_RTPFB_TMMBNItem;
return true;
}
case 5:
{
// RTCP-SR-REQ Rapid Synchronisation of RTP Flows
// draft-perkins-avt-rapid-rtp-sync-03.txt
// trigger a new RTCP SR
_packetType = kRtcpRtpfbSrReqCode;
// Note: No state transition, SR REQ is empty!
return true;
}
default:
break;
}
EndCurrentBlock();
return false;
}
else if (header.PT == PT_PSFB)
{
// Payload specific feedback
switch (header.IC)
{
case 1:
// PLI
_packetType = kRtcpPsfbPliCode;
_packet.PLI.SenderSSRC = senderSSRC;
_packet.PLI.MediaSSRC = mediaSSRC;
// Note: No state transition, PLI FCI is empty!
return true;
case 2:
// SLI
_packetType = kRtcpPsfbSliCode;
_packet.SLI.SenderSSRC = senderSSRC;
_packet.SLI.MediaSSRC = mediaSSRC;
_state = State_PSFB_SLIItem;
return true;
case 3:
_packetType = kRtcpPsfbRpsiCode;
_packet.RPSI.SenderSSRC = senderSSRC;
_packet.RPSI.MediaSSRC = mediaSSRC;
_state = State_PSFB_RPSIItem;
return true;
case 4:
// FIR
_packetType = kRtcpPsfbFirCode;
_packet.FIR.SenderSSRC = senderSSRC;
_packet.FIR.MediaSSRC = mediaSSRC;
_state = State_PSFB_FIRItem;
return true;
default:
break;
}
EndCurrentBlock();
return false;
}
else
{
assert(false);
EndCurrentBlock();
return false;
}
}
bool
RTCPUtility::RTCPParserV2::ParseRPSIItem()
{
// RFC 4585 6.3.3. Reference Picture Selection Indication (RPSI)
/*
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| PB |0| Payload Type| Native RPSI bit string |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| defined per codec ... | Padding (0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 4)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
if(length > 2+RTCP_RPSI_DATA_SIZE)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packetType = kRtcpPsfbRpsiCode;
WebRtc_UWord8 paddingBits = *_ptrRTCPData++;
_packet.RPSI.PayloadType = *_ptrRTCPData++;
memcpy(_packet.RPSI.NativeBitString, _ptrRTCPData, length-2);
_packet.RPSI.NumberOfValidBits = WebRtc_UWord16(length-2)*8 - paddingBits;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseNACKItem()
{
// RFC 4585 6.2.1. Generic NACK
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 4)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packetType = kRtcpRtpfbNackItemCode;
_packet.NACKItem.PacketID = *_ptrRTCPData++ << 8;
_packet.NACKItem.PacketID += *_ptrRTCPData++;
_packet.NACKItem.BitMask = *_ptrRTCPData++ << 8;
_packet.NACKItem.BitMask += *_ptrRTCPData++;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseTMMBRItem()
{
// RFC 5104 4.2.1. Temporary Maximum Media Stream Bit Rate Request (TMMBR)
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 8)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packetType = kRtcpRtpfbTmmbrItemCode;
_packet.TMMBRItem.SSRC = *_ptrRTCPData++ << 24;
_packet.TMMBRItem.SSRC += *_ptrRTCPData++ << 16;
_packet.TMMBRItem.SSRC += *_ptrRTCPData++ << 8;
_packet.TMMBRItem.SSRC += *_ptrRTCPData++;
WebRtc_UWord8 mxtbrExp = (_ptrRTCPData[0] >> 2) & 0x3F;
WebRtc_UWord32 mxtbrMantissa = (_ptrRTCPData[0] & 0x03) << 15;
mxtbrMantissa += (_ptrRTCPData[1] << 7);
mxtbrMantissa += (_ptrRTCPData[2] >> 1) & 0x7F;
WebRtc_UWord32 measuredOH = (_ptrRTCPData[2] & 0x01) << 8;
measuredOH += _ptrRTCPData[3];
_ptrRTCPData += 4; // Fwd read data
_packet.TMMBRItem.MaxTotalMediaBitRate = ((mxtbrMantissa << mxtbrExp) / 1000);
_packet.TMMBRItem.MeasuredOverhead = measuredOH;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseTMMBNItem()
{
// RFC 5104 4.2.2. Temporary Maximum Media Stream Bit Rate Notification (TMMBN)
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 8)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packetType = kRtcpRtpfbTmmbnItemCode;
_packet.TMMBNItem.SSRC = *_ptrRTCPData++ << 24;
_packet.TMMBNItem.SSRC += *_ptrRTCPData++ << 16;
_packet.TMMBNItem.SSRC += *_ptrRTCPData++ << 8;
_packet.TMMBNItem.SSRC += *_ptrRTCPData++;
WebRtc_UWord8 mxtbrExp = (_ptrRTCPData[0] >> 2) & 0x3F;
WebRtc_UWord32 mxtbrMantissa = (_ptrRTCPData[0] & 0x03) << 15;
mxtbrMantissa += (_ptrRTCPData[1] << 7);
mxtbrMantissa += (_ptrRTCPData[2] >> 1) & 0x7F;
WebRtc_UWord32 measuredOH = (_ptrRTCPData[2] & 0x01) << 8;
measuredOH += _ptrRTCPData[3];
_ptrRTCPData += 4; // Fwd read data
_packet.TMMBNItem.MaxTotalMediaBitRate = ((mxtbrMantissa << mxtbrExp) / 1000);
_packet.TMMBNItem.MeasuredOverhead = measuredOH;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseSLIItem()
{
// RFC 5104 6.3.2. Slice Loss Indication (SLI)
/*
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| First | Number | PictureID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 4)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packetType = kRtcpPsfbSliItemCode;
WebRtc_UWord32 buffer;
buffer = *_ptrRTCPData++ << 24;
buffer += *_ptrRTCPData++ << 16;
buffer += *_ptrRTCPData++ << 8;
buffer += *_ptrRTCPData++;
_packet.SLIItem.FirstMB = WebRtc_UWord16((buffer>>19) & 0x1fff);
_packet.SLIItem.NumberOfMB = WebRtc_UWord16((buffer>>6) & 0x1fff);
_packet.SLIItem.PictureId = WebRtc_UWord8(buffer & 0x3f);
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseFIRItem()
{
// RFC 5104 4.3.1. Full Intra Request (FIR)
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 8)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packetType = kRtcpPsfbFirItemCode;
_packet.FIRItem.SSRC = *_ptrRTCPData++ << 24;
_packet.FIRItem.SSRC += *_ptrRTCPData++ << 16;
_packet.FIRItem.SSRC += *_ptrRTCPData++ << 8;
_packet.FIRItem.SSRC += *_ptrRTCPData++;
_packet.FIRItem.CommandSequenceNumber = *_ptrRTCPData++;
_ptrRTCPData += 3; // Skip "Reserved" bytes.
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseAPP( const RTCPCommonHeader& header)
{
ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 12) // 4 * 3, RFC 3550 6.7 APP: Application-Defined RTCP Packet
{
EndCurrentBlock();
return false;
}
_ptrRTCPData += 4; // Skip RTCP header
WebRtc_UWord32 senderSSRC = *_ptrRTCPData++ << 24;
senderSSRC += *_ptrRTCPData++ << 16;
senderSSRC += *_ptrRTCPData++ << 8;
senderSSRC += *_ptrRTCPData++;
WebRtc_UWord32 name = *_ptrRTCPData++ << 24;
name += *_ptrRTCPData++ << 16;
name += *_ptrRTCPData++ << 8;
name += *_ptrRTCPData++;
length = _ptrRTCPBlockEnd - _ptrRTCPData;
_packetType = kRtcpAppCode;
_packet.APP.SubType = header.IC;
_packet.APP.Name = name;
_state = State_AppItem;
return true;
}
bool
RTCPUtility::RTCPParserV2::ParseAPPItem()
{
const ptrdiff_t length = _ptrRTCPBlockEnd - _ptrRTCPData;
if (length < 4)
{
_state = State_TopLevel;
EndCurrentBlock();
return false;
}
_packetType = kRtcpAppItemCode;
if(length > kRtcpAppCode_DATA_SIZE)
{
memcpy(_packet.APP.Data, _ptrRTCPData, kRtcpAppCode_DATA_SIZE);
_packet.APP.Size = kRtcpAppCode_DATA_SIZE;
_ptrRTCPData += kRtcpAppCode_DATA_SIZE;
}else
{
memcpy(_packet.APP.Data, _ptrRTCPData, length);
_packet.APP.Size = (WebRtc_UWord16)length;
_ptrRTCPData += length;
}
return true;
}
RTCPUtility::RTCPPacketIterator::RTCPPacketIterator(
WebRtc_UWord8* rtcpData,
size_t rtcpDataLength)
:
_ptrBegin(rtcpData),
_ptrEnd(rtcpData + rtcpDataLength)
{
}
RTCPUtility::RTCPPacketIterator::~RTCPPacketIterator()
{
}
const RTCPUtility::RTCPCommonHeader*
RTCPUtility::RTCPPacketIterator::Begin()
{
_ptrBlock = _ptrBegin;
return Iterate();
}
const RTCPUtility::RTCPCommonHeader*
RTCPUtility::RTCPPacketIterator::Iterate()
{
const bool success = RTCPParseCommonHeader(_ptrBlock, _ptrEnd, _header);
if (!success)
{
_ptrBlock = NULL;
return NULL;
}
_ptrBlock += _header.LengthInOctets;
if (_ptrBlock > _ptrEnd)
{
_ptrBlock = NULL;
return NULL;
}
return &_header;
}
const RTCPUtility::RTCPCommonHeader*
RTCPUtility::RTCPPacketIterator::Current()
{
if (!_ptrBlock)
{
return NULL;
}
return &_header;
}
} // namespace webrtc