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package ackhandler
import (
mocklogging "github.com/quic-go/quic-go/internal/mocks/logging"
"github.com/quic-go/quic-go/internal/protocol"
"github.com/quic-go/quic-go/internal/utils"
"github.com/quic-go/quic-go/logging"
. "github.com/onsi/ginkgo/v2"
. "github.com/onsi/gomega"
)
var _ = Describe("ECN tracker", func() {
var ecnTracker *ecnTracker
var tracer *mocklogging.MockConnectionTracer
getAckedPackets := func(pns ...protocol.PacketNumber) []*packet {
var packets []*packet
for _, p := range pns {
packets = append(packets, &packet{PacketNumber: p})
}
return packets
}
BeforeEach(func() {
var tr *logging.ConnectionTracer
tr, tracer = mocklogging.NewMockConnectionTracer(mockCtrl)
ecnTracker = newECNTracker(utils.DefaultLogger, tr)
})
It("sends exactly 10 testing packets", func() {
tracer.EXPECT().ECNStateUpdated(logging.ECNStateTesting, logging.ECNTriggerNoTrigger)
for i := 0; i < 9; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
// Do this twice to make sure only sent packets are counted
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
ecnTracker.SentPacket(protocol.PacketNumber(10+i), protocol.ECT0)
}
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
tracer.EXPECT().ECNStateUpdated(logging.ECNStateUnknown, logging.ECNTriggerNoTrigger)
ecnTracker.SentPacket(20, protocol.ECT0)
// In unknown state, packets shouldn't be ECN-marked.
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
})
sendAllTestingPackets := func() {
tracer.EXPECT().ECNStateUpdated(logging.ECNStateTesting, logging.ECNTriggerNoTrigger)
tracer.EXPECT().ECNStateUpdated(logging.ECNStateUnknown, logging.ECNTriggerNoTrigger)
for i := 0; i < 10; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECT0)
}
}
It("fails ECN validation if all ECN testing packets are lost", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
for i := 0; i < 9; i++ {
ecnTracker.LostPacket(protocol.PacketNumber(i))
}
// We don't care about the loss of non-testing packets
ecnTracker.LostPacket(15)
// Now lose the last testing packet.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedLostAllTestingPackets)
ecnTracker.LostPacket(9)
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
// We still don't care about more non-testing packets being lost
ecnTracker.LostPacket(16)
})
It("only detects ECN mangling after sending all testing packets", func() {
tracer.EXPECT().ECNStateUpdated(logging.ECNStateTesting, logging.ECNTriggerNoTrigger)
for i := 0; i < 9; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECT0)
ecnTracker.LostPacket(protocol.PacketNumber(i))
}
// Send the last testing packet, and receive a
tracer.EXPECT().ECNStateUpdated(logging.ECNStateUnknown, logging.ECNTriggerNoTrigger)
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
ecnTracker.SentPacket(9, protocol.ECT0)
// Now lose the last testing packet.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedLostAllTestingPackets)
ecnTracker.LostPacket(9)
})
It("passes ECN validation when a testing packet is acknowledged, while still in testing state", func() {
tracer.EXPECT().ECNStateUpdated(logging.ECNStateTesting, logging.ECNTriggerNoTrigger)
for i := 0; i < 5; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECT0)
}
tracer.EXPECT().ECNStateUpdated(logging.ECNStateCapable, logging.ECNTriggerNoTrigger)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(3), 1, 0, 0)).To(BeFalse())
// make sure we continue sending ECT(0) packets
for i := 5; i < 100; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECT0)
}
})
It("passes ECN validation when a testing packet is acknowledged, while in unknown state", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// Lose some packets to make sure this doesn't influence the outcome.
for i := 0; i < 5; i++ {
ecnTracker.LostPacket(protocol.PacketNumber(i))
}
tracer.EXPECT().ECNStateUpdated(logging.ECNStateCapable, logging.ECNTriggerNoTrigger)
Expect(ecnTracker.HandleNewlyAcked([]*packet{{PacketNumber: 7}}, 1, 0, 0)).To(BeFalse())
})
It("fails ECN validation when the ACK contains more ECN counts than we sent packets", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// only 10 ECT(0) packets were sent, but the ACK claims to have received 12 of them
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedMoreECNCountsThanSent)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12), 12, 0, 0)).To(BeFalse())
})
It("fails ECN validation when the ACK contains ECN counts for the wrong code point", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// We sent ECT(0), but this ACK acknowledges ECT(1).
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedMoreECNCountsThanSent)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12), 0, 1, 0)).To(BeFalse())
})
It("fails ECN validation when the ACK doesn't contain ECN counts", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// First only acknowledge packets sent without ECN marks.
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(12, 13, 14), 0, 0, 0)).To(BeFalse())
// Now acknowledge some packets sent with ECN marks.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedNoECNCounts)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(1, 2, 3, 15), 0, 0, 0)).To(BeFalse())
})
It("fails ECN validation when an ACK decreases ECN counts", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
tracer.EXPECT().ECNStateUpdated(logging.ECNStateCapable, logging.ECNTriggerNoTrigger)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(1, 2, 3, 12), 3, 0, 0)).To(BeFalse())
// Now acknowledge some more packets, but decrease the ECN counts. Obviously, this doesn't make any sense.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedDecreasedECNCounts)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(4, 5, 6, 13), 2, 0, 0)).To(BeFalse())
// make sure that new ACKs are ignored
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(7, 8, 9, 14), 5, 0, 0)).To(BeFalse())
})
// This can happen if ACK are lost / reordered.
It("doesn't fail validation if the ACK contains more ECN counts than it acknowledges packets", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
tracer.EXPECT().ECNStateUpdated(logging.ECNStateCapable, logging.ECNTriggerNoTrigger)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(1, 2, 3, 12), 8, 0, 0)).To(BeFalse())
})
It("fails ECN validation when the ACK doesn't contain enough ECN counts", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// First only acknowledge some packets sent with ECN marks.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateCapable, logging.ECNTriggerNoTrigger)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(1, 2, 3, 12), 2, 0, 1)).To(BeTrue())
// Now acknowledge some more packets sent with ECN marks, but don't increase the counters enough.
// This ACK acknowledges 3 more ECN-marked packets, but the counters only increase by 2.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedTooFewECNCounts)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(4, 5, 6, 15), 3, 0, 2)).To(BeFalse())
})
It("detects ECN mangling if all testing packets are marked CE", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// ECN capability not confirmed yet, therefore CE marks are not regarded as congestion events
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(0, 1, 2, 3), 0, 0, 4)).To(BeFalse())
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(4, 5, 6, 10, 11, 12), 0, 0, 7)).To(BeFalse())
// With the next ACK, all testing packets will now have been marked CE.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedManglingDetected)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(7, 8, 9, 13), 0, 0, 10)).To(BeFalse())
})
It("only detects ECN mangling after sending all testing packets", func() {
tracer.EXPECT().ECNStateUpdated(logging.ECNStateTesting, logging.ECNTriggerNoTrigger)
for i := 0; i < 9; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECT0)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(protocol.PacketNumber(i)), 0, 0, int64(i+1))).To(BeFalse())
}
// Send the last testing packet, and receive a
tracer.EXPECT().ECNStateUpdated(logging.ECNStateUnknown, logging.ECNTriggerNoTrigger)
Expect(ecnTracker.Mode()).To(Equal(protocol.ECT0))
ecnTracker.SentPacket(9, protocol.ECT0)
// This ACK now reports the last testing packets as CE as well.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedManglingDetected)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(9), 0, 0, 10)).To(BeFalse())
})
It("detects ECN mangling, if some testing packets are marked CE, and then others are lost", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// ECN capability not confirmed yet, therefore CE marks are not regarded as congestion events
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(0, 1, 2, 3), 0, 0, 4)).To(BeFalse())
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(6, 7, 8, 9), 0, 0, 8)).To(BeFalse())
// Lose one of the two unacknowledged packets.
ecnTracker.LostPacket(4)
// By losing the last unacknowledged testing packets, we should detect the mangling.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedManglingDetected)
ecnTracker.LostPacket(5)
})
It("detects ECN mangling, if some testing packets are lost, and then others are marked CE", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// Lose a few packets.
ecnTracker.LostPacket(0)
ecnTracker.LostPacket(1)
ecnTracker.LostPacket(2)
// ECN capability not confirmed yet, therefore CE marks are not regarded as congestion events
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(3, 4, 5, 6, 7, 8), 0, 0, 6)).To(BeFalse())
// By CE-marking the last unacknowledged testing packets, we should detect the mangling.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateFailed, logging.ECNFailedManglingDetected)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(9), 0, 0, 7)).To(BeFalse())
})
It("declares congestion", func() {
sendAllTestingPackets()
for i := 10; i < 20; i++ {
Expect(ecnTracker.Mode()).To(Equal(protocol.ECNNon))
ecnTracker.SentPacket(protocol.PacketNumber(i), protocol.ECNNon)
}
// Receive one CE count.
tracer.EXPECT().ECNStateUpdated(logging.ECNStateCapable, logging.ECNTriggerNoTrigger)
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(1, 2, 3, 12), 2, 0, 1)).To(BeTrue())
// No increase in CE. No congestion.
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(4, 5, 6, 13), 5, 0, 1)).To(BeFalse())
// Increase in CE. More congestion.
Expect(ecnTracker.HandleNewlyAcked(getAckedPackets(7, 8, 9, 14), 7, 0, 2)).To(BeTrue())
})
})
|
