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Merged
levy merged 4 commits into from
Sep 14, 2026
Merged

ieee80211: correct Block Ack and aggregation frame representations #1188

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75099f1
ieee80211: fix: Block Ack action wire encoding
mgonzalezlopezudc Sep 11, 2026
b4a6bd8
ieee80211: fix: HT MPDU delimiter wire encoding
mgonzalezlopezudc Sep 11, 2026
1322a98
ieee80211: fix: management timestamp consumption
mgonzalezlopezudc Sep 11, 2026
0ff8df4
ieee80211: fix: A-MSDU header addresses and lengths
mgonzalezlopezudc Sep 11, 2026
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2 changes: 1 addition & 1 deletion src/inet/linklayer/ieee80211/mac/Ieee80211Frame.msg
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Original file line number Diff line number Diff line change
Expand Up @@ -312,7 +312,7 @@ class Ieee80211AddbaResponse extends Ieee80211ActionFrame
//
class Ieee80211Delba extends Ieee80211ActionFrame
{
chunkLength = LENGTH_DELBA;
chunkLength = LENGTH_DELBA - B(4); // FCS is carried by Ieee80211MacTrailer
category = 3; // Category field is set to 3 (representing DELBA). (1 byte)
blockAckAction = 2; // Block Ack Action field is set to 2 (representing DELBA). (1 byte)

Expand Down
108 changes: 62 additions & 46 deletions src/inet/linklayer/ieee80211/mac/Ieee80211MacHeaderSerializer.cc
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Expand Up @@ -7,6 +7,7 @@

#include "inet/linklayer/ieee80211/mac/Ieee80211MacHeaderSerializer.h"

#include "inet/common/checksum/Checksum.h"
#include "inet/common/packet/serializer/ChunkSerializerRegistry.h"

namespace inet {
Expand Down Expand Up @@ -64,6 +65,19 @@ uint16_t packSequenceControl(uint8_t fragmentNumber, uint16_t sequenceNumber)
return (fragmentNumber & 0xF) | ((sequenceNumber & 0xFFF) << 4);
}

uint16_t packBlockAckParameters(bool aMsduSupported, bool blockAckPolicy, uint8_t tid, uint16_t bufferSize)
{
// IEEE Std 802.11-2024, 9.4.1.13, Figure 9-151.
return aMsduSupported | (blockAckPolicy << 1) | ((tid & 0xF) << 2) | ((bufferSize & 0x3FF) << 6);
}

uint8_t computeMpduDelimiterCrc(uint16_t delimiter)
{
// IEEE Std 802.11-2024, 9.7.2: x^8 + x^2 + x + 1, complemented remainder.
const uint8_t bytes[] = {uint8_t(delimiter), uint8_t(delimiter >> 8)};
return generic_crc8(bytes, sizeof(bytes), 0x07, 0xFF, true, true, 0xFF);
}

void writeSequenceControl(MemoryOutputStream& stream, uint8_t fragmentNumber, uint16_t sequenceNumber)
{
stream.writeUint16Le(packSequenceControl(fragmentNumber, sequenceNumber));
Expand Down Expand Up @@ -126,24 +140,25 @@ const Ptr<Chunk> Ieee80211MsduSubframeHeaderSerializer::deserializeFields(Memory
void Ieee80211MpduSubframeHeaderSerializer::serializeFields(MemoryOutputStream& stream, const Ptr<const Chunk>& chunk) const
{
auto mpduSubframe = dynamicPtrCast<const Ieee80211MpduSubframeHeader>(chunk);
stream.writeUint4(0);
stream.writeUint4(mpduSubframe->getLength() >> 8);
stream.writeUint8(mpduSubframe->getLength() & 0xFF);
stream.writeByte(0);
// IEEE Std 802.11-2024, 9.7.1, Figures 9-1329/9-1330: HT length occupies B4-B15.
int length = mpduSubframe->getLength();
if (length < 0 || length > 0xFFF)
throw cRuntimeError("HT MPDU delimiter length is outside the 12-bit range: %d", length);
uint16_t delimiter = length << 4;
stream.writeUint16Le(delimiter);
stream.writeByte(computeMpduDelimiterCrc(delimiter));
stream.writeByte(0x4E);
}

const Ptr<Chunk> Ieee80211MpduSubframeHeaderSerializer::deserializeFields(MemoryInputStream& stream, const std::type_info&) const
{
auto mpduSubframe = makeShared<Ieee80211MpduSubframeHeader>();
stream.readUint4();
// IEEE Std 802.11-2024, 9.7.1, Table 9-659 and Figure 9-1330:
// in an HT PPDU, MPDU Length Low is 12 bits and MPDU Length High is reserved.
int length = stream.readUint4() << 8;
length |= stream.readUint8();
mpduSubframe->setLength(length);
stream.readByte();
stream.readByte();
auto delimiter = stream.readUint16Le();
mpduSubframe->setLength(delimiter >> 4);
auto crc = stream.readByte();
auto signature = stream.readByte();
if (crc != computeMpduDelimiterCrc(delimiter) || signature != 0x4E)
mpduSubframe->markIncorrect();
return mpduSubframe;
}

Expand Down Expand Up @@ -195,36 +210,32 @@ void Ieee80211MacHeaderSerializer::serializeFields(MemoryOutputStream& stream, c
auto addbaRequest = dynamicPtrCast<const Ieee80211AddbaRequest>(chunk);
stream.writeByte(addbaRequest->getBlockAckAction());
stream.writeByte(addbaRequest->getDialogToken());
stream.writeBit(addbaRequest->getAMsduSupported());
stream.writeBit(addbaRequest->getBlockAckPolicy());
stream.writeUint4(addbaRequest->getTid());
stream.writeNBitsOfUint64Be(addbaRequest->getBufferSize(), 10);
stream.writeUint16Be(addbaRequest->getBlockAckTimeoutValue().inUnit(SIMTIME_US) / 1024);
stream.writeUint4(addbaRequest->get_fragmentNumber());
stream.writeNBitsOfUint64Be(addbaRequest->getStartingSequenceNumber().get(), 12);
stream.writeUint16Le(packBlockAckParameters(addbaRequest->getAMsduSupported(),
addbaRequest->getBlockAckPolicy(), addbaRequest->getTid(), addbaRequest->getBufferSize()));
stream.writeUint16Le(addbaRequest->getBlockAckTimeoutValue().inUnit(SIMTIME_US) / 1024);
// IEEE Std 802.11-2024, 9.6.4.2: Fragment Number is zero.
writeSequenceControl(stream, 0, addbaRequest->getStartingSequenceNumber().get());
ASSERT(stream.getLength() - startPos == addbaRequest->getChunkLength());
break;
}
case 1: {
auto addbaResponse = dynamicPtrCast<const Ieee80211AddbaResponse>(chunk);
stream.writeByte(addbaResponse->getBlockAckAction());
stream.writeByte(addbaResponse->getDialogToken());
stream.writeUint16Be(addbaResponse->getStatusCode());
stream.writeBit(addbaResponse->getAMsduSupported());
stream.writeBit(addbaResponse->getBlockAckPolicy());
stream.writeUint4(addbaResponse->getTid());
stream.writeNBitsOfUint64Be(addbaResponse->getBufferSize(), 10);
stream.writeUint16Be(addbaResponse->getBlockAckTimeoutValue().inUnit(SIMTIME_US) / 1024);
stream.writeUint16Le(addbaResponse->getStatusCode());
stream.writeUint16Le(packBlockAckParameters(addbaResponse->getAMsduSupported(),
addbaResponse->getBlockAckPolicy(), addbaResponse->getTid(), addbaResponse->getBufferSize()));
stream.writeUint16Le(addbaResponse->getBlockAckTimeoutValue().inUnit(SIMTIME_US) / 1024);
ASSERT(stream.getLength() - startPos == addbaResponse->getChunkLength());
break;
}
case 2: {
auto delba = dynamicPtrCast<const Ieee80211Delba>(chunk);
stream.writeByte(delba->getBlockAckAction());
stream.writeNBitsOfUint64Be(delba->getReserved(), 11);
stream.writeBit(delba->getInitiator());
stream.writeUint4(delba->getTid());
stream.writeUint16Be(delba->getReasonCode());
// IEEE Std 802.11-2024, 9.4.1.16, Figure 9-154.
stream.writeUint16Le((delba->getReserved() & 0x7FF) |
(delba->getInitiator() << 11) | ((delba->getTid() & 0xF) << 12));
stream.writeUint16Le(delba->getReasonCode());
ASSERT(stream.getLength() - startPos == delba->getChunkLength());
break;
}
Expand Down Expand Up @@ -437,13 +448,15 @@ const Ptr<Chunk> Ieee80211MacHeaderSerializer::deserializeFields(MemoryInputStre
copyActionFrameFields(addbaRequest, actionFrame);
addbaRequest->setBlockAckAction(blockAckAction);
addbaRequest->setDialogToken(stream.readByte());
addbaRequest->setAMsduSupported(stream.readBit());
addbaRequest->setBlockAckPolicy(stream.readBit());
addbaRequest->setTid(stream.readUint4());
addbaRequest->setBufferSize(stream.readNBitsToUint64Be(10));
addbaRequest->setBlockAckTimeoutValue(SimTime(stream.readUint16Be() * 1024, SIMTIME_US));
addbaRequest->set_fragmentNumber(stream.readUint4());
addbaRequest->setStartingSequenceNumber(SequenceNumberCyclic(stream.readNBitsToUint64Be(12)));
auto parameters = stream.readUint16Le();
addbaRequest->setAMsduSupported(parameters & 1);
addbaRequest->setBlockAckPolicy(parameters & 2);
addbaRequest->setTid((parameters >> 2) & 0xF);
addbaRequest->setBufferSize(parameters >> 6);
addbaRequest->setBlockAckTimeoutValue(SimTime(stream.readUint16Le() * 1024, SIMTIME_US));
readSequenceControl(stream, fragmentNumber, sequenceNumber);
addbaRequest->set_fragmentNumber(fragmentNumber);
addbaRequest->setStartingSequenceNumber(sequenceNumber);
return addbaRequest;
}
case 1: {
Expand All @@ -452,22 +465,25 @@ const Ptr<Chunk> Ieee80211MacHeaderSerializer::deserializeFields(MemoryInputStre
copyActionFrameFields(addbaResponse, actionFrame);
addbaResponse->setBlockAckAction(blockAckAction);
addbaResponse->setDialogToken(stream.readByte());
addbaResponse->setStatusCode(stream.readUint16Be());
addbaResponse->setAMsduSupported(stream.readBit());
addbaResponse->setBlockAckPolicy(stream.readBit());
addbaResponse->setTid(stream.readUint4());
addbaResponse->setBufferSize(stream.readNBitsToUint64Be(10));
addbaResponse->setBlockAckTimeoutValue(SimTime(stream.readUint16Be() * 1024, SIMTIME_US));
addbaResponse->setStatusCode(stream.readUint16Le());
auto parameters = stream.readUint16Le();
addbaResponse->setAMsduSupported(parameters & 1);
addbaResponse->setBlockAckPolicy(parameters & 2);
addbaResponse->setTid((parameters >> 2) & 0xF);
addbaResponse->setBufferSize(parameters >> 6);
addbaResponse->setBlockAckTimeoutValue(SimTime(stream.readUint16Le() * 1024, SIMTIME_US));
return addbaResponse;
}
case 2: {
auto delba = makeShared<Ieee80211Delba>();
copyBasicFields(delba, macHeader);
copyActionFrameFields(delba, actionFrame);
delba->setBlockAckAction(blockAckAction);
delba->setReserved(stream.readNBitsToUint64Be(11));
delba->setInitiator(stream.readBit());
delba->setTid(stream.readUint4());
delba->setReasonCode(stream.readUint16Be());
auto parameters = stream.readUint16Le();
delba->setReserved(parameters & 0x7FF);
delba->setInitiator(parameters & 0x800);
delba->setTid(parameters >> 12);
delba->setReasonCode(stream.readUint16Le());
return delba;
}
default:
Expand Down
17 changes: 16 additions & 1 deletion src/inet/linklayer/ieee80211/mac/aggregation/MsduAggregation.cc
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Expand Up @@ -84,9 +84,24 @@ Packet *MsduAggregation::aggregateFrames(std::vector<Packet *> *frames)
amsduHeader->setFromDS(fromDS);
amsduHeader->setAMsduPresent(true);
amsduHeader->setReceiverAddress(ra);
// IEEE Std 802.11-2024, 9.3.2.2.1: aggregation preserves the common RA and TA.
amsduHeader->setTransmitterAddress(firstHeader->getTransmitterAddress());
amsduHeader->setTid(tid);
amsduHeader->addChunkLength(QOSCONTROL_PART_LENGTH);
// TODO set addr3 and addr4 according to fromDS and toDS.
// IEEE Std 802.11-2024, 9.3.2.1.1, Figure 9-119.
if (toDS && fromDS)
amsduHeader->addChunkLength(B(6));
// IEEE Std 802.11-2024, 9.3.2.1.2, Table 9-60: Basic A-MSDUs carry the
// BSSID in Address3 and, when present, Address4. In the AP-to-AP case,
// the BSSID is the address of the transmitting AP.
if (fromDS)
amsduHeader->setAddress3(firstHeader->getTransmitterAddress());
else if (toDS)
amsduHeader->setAddress3(ra);
else
amsduHeader->setAddress3(firstHeader->getAddress3());
if (toDS && fromDS)
amsduHeader->setAddress4(firstHeader->getTransmitterAddress());
aggregatedFrame->insertAtFront(amsduHeader);
aggregatedFrame->insertAtBack(makeShared<Ieee80211MacTrailer>());
aggregatedFrame->setName(aggregatedName.c_str());
Expand Down
4 changes: 4 additions & 0 deletions src/inet/linklayer/ieee80211/mac/aggregation/MsduDeaggregation.cc
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Expand Up @@ -19,6 +19,7 @@ void MsduDeaggregation::setExplodedFrameAddress(const Ptr<Ieee80211DataHeader>&
if (fromDS == 0 && toDS == 0) { // STA to STA
header->setTransmitterAddress(aMsduHeader->getTransmitterAddress());
header->setReceiverAddress(aMsduHeader->getReceiverAddress());
header->setAddress3(aMsduHeader->getAddress3());
}
else if (fromDS == 1 && toDS == 0) { // AP to STA
header->setTransmitterAddress(aMsduHeader->getTransmitterAddress());
Expand Down Expand Up @@ -64,6 +65,9 @@ std::vector<Packet *> *MsduDeaggregation::deaggregateFrame(Packet *aggregatedFra
header->addChunkLength(QOSCONTROL_PART_LENGTH);
header->setToDS(amsduHeader->getToDS());
header->setFromDS(amsduHeader->getFromDS());
// IEEE Std 802.11-2024, 9.3.2.1.1, Figure 9-119: Address4 adds six octets.
if (header->getToDS() && header->getFromDS())
header->addChunkLength(B(6));
header->setTid(tid);
header->setSequenceNumber(SequenceNumberCyclic(0));
setExplodedFrameAddress(header, msduSubframeHeader, amsduHeader);
Expand Down
10 changes: 6 additions & 4 deletions src/inet/linklayer/ieee80211/mgmt/Ieee80211MgmtFrameSerializer.cc
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Expand Up @@ -758,8 +758,9 @@ const Ptr<Chunk> Ieee80211MgmtFrameSerializer::deserializeFields(MemoryInputStre
else if (typeInfo == typeid(Ieee80211BeaconFrame)) {
auto frame = makeShared<Ieee80211BeaconFrame>();

simtime_t timetstamp;
timetstamp.setRaw(stream.readUint64Le()); // TODO store timestamp
// IEEE Std 802.11-2024, 9.4.1.10 and 11.1.3.1: unsigned TSF counter in microseconds.
// The model does not retain TSF; no conversion to simulation-resolution ticks is needed.
stream.readUint64Le();

frame->setBeaconInterval(SimTime((int64_t)stream.readUint16Le() * 1024, SIMTIME_US));
stream.readUint16Le(); // Capability
Expand All @@ -775,8 +776,9 @@ const Ptr<Chunk> Ieee80211MgmtFrameSerializer::deserializeFields(MemoryInputStre
else if (typeInfo == typeid(Ieee80211ProbeResponseFrame)) {
auto frame = makeShared<Ieee80211ProbeResponseFrame>();

simtime_t timestamp;
timestamp.setRaw(stream.readUint64Le()); // TODO store timestamp
// IEEE Std 802.11-2024, 9.4.1.10 and 11.1.3.1: unsigned TSF counter in microseconds.
// The model does not retain TSF; no conversion to simulation-resolution ticks is needed.
stream.readUint64Le();

frame->setBeaconInterval(SimTime((int64_t)stream.readUint16Le() * 1024, SIMTIME_US));
stream.readUint16Le();
Expand Down
8 changes: 4 additions & 4 deletions tests/fingerprint/examples.csv
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Expand Up @@ -7,7 +7,7 @@
# /examples/adhoc/ieee80211/, -f omnetpp.ini -c Ping2 -r 0, 100s, 0000-0000/tplx;0000-0000/~tNl;0000-0000/~tND, ERROR, wireless adhoc # [Config Ping2] # interactive config, needed a *.numHosts parameter
/examples/adhoc/qos/, -f omnetpp.ini -c MacNonQos -r 0, 10s, 5749-0281/tplx;f38a-cb93/~tNl;fd9b-683f/~tND;0eb8-3e3b/tyf, PASS, wireless adhoc Ipv4
/examples/adhoc/qos/, -f omnetpp.ini -c MacQos -r 0, 10s, 1486-cbae/tplx;521b-977a/~tNl;91c2-9aa9/~tND;2c1e-66e5/tyf, PASS, wireless adhoc Ipv4
/examples/adhoc/qos/, -f omnetpp.ini -c MacQos -r 1, 10s, 783f-d09a/tplx;13d1-ec15/~tNl;5aaf-cc7c/~tND;a587-3a4d/tyf, PASS, wireless adhoc Ipv4
/examples/adhoc/qos/, -f omnetpp.ini -c MacQos -r 1, 10s, 783f-d09a/tplx;13d1-ec15/~tNl;a50d-9ad8/~tND;a587-3a4d/tyf, PASS, wireless adhoc Ipv4
/examples/adhoc/qos/, -f omnetpp.ini -c Fragmentation, 10s, 9c66-e6f0/tplx;cc9e-d1a6/~tNl;53c8-e1b0/~tND;33b7-00f9/tyf, PASS, wireless adhoc Ipv4
/examples/adhoc/qos/, -f omnetpp.ini -c MsduAggregation, 10s, 85bd-85c6/tplx;22f6-085d/~tNl;dc0d-4e19/~tND;df04-18f7/tyf, PASS, wireless adhoc Ipv4

Expand Down Expand Up @@ -655,10 +655,10 @@
/examples/wireless/power/, -f omnetpp.ini -c General -r 0, 100s, 6fae-d558/tplx;b8ea-b2fc/~tNl;5ea8-2cea/~tND, PASS, wireless Ipv4

/examples/wireless/qos/, -f omnetpp.ini -c MacNonQos -r 0, 10s, f252-8a4b/tplx;481d-4747/~tNl;5962-e45d/~tND;6097-a429/tyf, PASS, wireless Ipv4
/examples/wireless/qos/, -f omnetpp.ini -c MacQos -r 0, 10s, 31b0-6212/tplx;82ec-9fde/~tNl;540d-c0a4/~tND;9f3c-4512/tyf, PASS, wireless Ipv4
/examples/wireless/qos/, -f omnetpp.ini -c MacQos -r 0, 10s, 31b0-6212/tplx;82ec-9fde/~tNl;9839-8fb0/~tND;9f3c-4512/tyf, PASS, wireless Ipv4
/examples/wireless/qos/, -f omnetpp.ini -c MacQosWithoutAggregation -r 0, 10s, acd6-0108/tplx;b339-294a/~tNl;75d4-11f9/~tND;a4c3-19bf/tyf, PASS, wireless Ipv4
/examples/wireless/qos/, -f omnetpp.ini -c MacQosWithRtsCts -r 0, 10s, 9ece-fbfb/tplx;c1af-29ff/~tNl;8fe3-d7a6/~tND;b2d6-1329/tyf, PASS, wireless Ipv4
/examples/wireless/qos/, -f omnetpp.ini -c MacQosWithBlockAck -r 0, 10s, d094-b008/tplx;173a-e3fb/~tNl;7147-4f5b/~tND;08b5-d005/tyf, PASS, wireless Ipv4
/examples/wireless/qos/, -f omnetpp.ini -c MacQosWithRtsCts -r 0, 10s, 9ece-fbfb/tplx;c1af-29ff/~tNl;4757-c17b/~tND;b2d6-1329/tyf, PASS, wireless Ipv4
/examples/wireless/qos/, -f omnetpp.ini -c MacQosWithBlockAck -r 0, 10s, d094-b008/tplx;173a-e3fb/~tNl;6541-bd60/~tND;08b5-d005/tyf, PASS, wireless Ipv4

/examples/wireless/ratecontrol/, -f omnetpp.ini -c Mac -r 0, 100s, bf30-2f13/tplx;7b2f-653d/~tNl;6e1e-3b7b/~tND;19fe-8b0e/tyf, PASS, wireless

Expand Down
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