329 lines
12 KiB
Go
329 lines
12 KiB
Go
package ackhandler
|
|
|
|
import (
|
|
"time"
|
|
|
|
"github.com/lucas-clemente/quic-go/frames"
|
|
"github.com/lucas-clemente/quic-go/protocol"
|
|
|
|
. "github.com/onsi/ginkgo"
|
|
. "github.com/onsi/gomega"
|
|
)
|
|
|
|
var _ = Describe("receivedPacketHandler", func() {
|
|
var (
|
|
handler *receivedPacketHandler
|
|
ackAlarmCallbackCalled bool
|
|
)
|
|
|
|
ackAlarmCallback := func(time.Time) {
|
|
ackAlarmCallbackCalled = true
|
|
}
|
|
|
|
BeforeEach(func() {
|
|
ackAlarmCallbackCalled = false
|
|
handler = NewReceivedPacketHandler(ackAlarmCallback).(*receivedPacketHandler)
|
|
})
|
|
|
|
Context("accepting packets", func() {
|
|
It("handles a packet that arrives late", func() {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(1), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedPacket(protocol.PacketNumber(3), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedPacket(protocol.PacketNumber(2), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
})
|
|
|
|
It("rejects packets with packet number 0", func() {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(0), true)
|
|
Expect(err).To(MatchError(errInvalidPacketNumber))
|
|
})
|
|
|
|
It("rejects a duplicate package", func() {
|
|
for i := 1; i < 5; i++ {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(i), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
}
|
|
err := handler.ReceivedPacket(4, true)
|
|
Expect(err).To(MatchError(ErrDuplicatePacket))
|
|
})
|
|
|
|
It("ignores a packet with PacketNumber less than the LeastUnacked of a previously received StopWaiting", func() {
|
|
err := handler.ReceivedPacket(5, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedStopWaiting(&frames.StopWaitingFrame{LeastUnacked: 10})
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedPacket(9, true)
|
|
Expect(err).To(MatchError(ErrPacketSmallerThanLastStopWaiting))
|
|
})
|
|
|
|
It("does not ignore a packet with PacketNumber equal to LeastUnacked of a previously received StopWaiting", func() {
|
|
err := handler.ReceivedPacket(5, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedStopWaiting(&frames.StopWaitingFrame{LeastUnacked: 10})
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedPacket(10, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
})
|
|
|
|
It("saves the time when each packet arrived", func() {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(3), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.largestObservedReceivedTime).To(BeTemporally("~", time.Now(), 10*time.Millisecond))
|
|
})
|
|
|
|
It("updates the largestObserved and the largestObservedReceivedTime", func() {
|
|
handler.largestObserved = 3
|
|
handler.largestObservedReceivedTime = time.Now().Add(-1 * time.Second)
|
|
err := handler.ReceivedPacket(5, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.largestObserved).To(Equal(protocol.PacketNumber(5)))
|
|
Expect(handler.largestObservedReceivedTime).To(BeTemporally("~", time.Now(), 10*time.Millisecond))
|
|
})
|
|
|
|
It("doesn't update the largestObserved and the largestObservedReceivedTime for a belated packet", func() {
|
|
timestamp := time.Now().Add(-1 * time.Second)
|
|
handler.largestObserved = 5
|
|
handler.largestObservedReceivedTime = timestamp
|
|
err := handler.ReceivedPacket(4, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.largestObserved).To(Equal(protocol.PacketNumber(5)))
|
|
Expect(handler.largestObservedReceivedTime).To(Equal(timestamp))
|
|
})
|
|
|
|
It("doesn't store more than MaxTrackedReceivedPackets packets", func() {
|
|
err := handler.ReceivedPacket(1, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
for i := protocol.PacketNumber(3); i < 3+protocol.MaxTrackedReceivedPackets-1; i++ {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(i), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
}
|
|
err = handler.ReceivedPacket(protocol.PacketNumber(protocol.MaxTrackedReceivedPackets)+10, true)
|
|
Expect(err).To(MatchError(errTooManyOutstandingReceivedPackets))
|
|
})
|
|
|
|
It("passes on errors from receivedPacketHistory", func() {
|
|
var err error
|
|
for i := protocol.PacketNumber(0); i < 5*protocol.MaxTrackedReceivedAckRanges; i++ {
|
|
err = handler.ReceivedPacket(2*i+1, true)
|
|
// this will eventually return an error
|
|
// details about when exactly the receivedPacketHistory errors are tested there
|
|
if err != nil {
|
|
break
|
|
}
|
|
}
|
|
Expect(err).To(MatchError(errTooManyOutstandingReceivedAckRanges))
|
|
})
|
|
})
|
|
|
|
Context("handling STOP_WAITING frames", func() {
|
|
It("increases the ignorePacketsBelow number", func() {
|
|
err := handler.ReceivedStopWaiting(&frames.StopWaitingFrame{LeastUnacked: protocol.PacketNumber(12)})
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ignorePacketsBelow).To(Equal(protocol.PacketNumber(11)))
|
|
})
|
|
|
|
It("increase the ignorePacketsBelow number, even if all packets below the LeastUnacked were already acked", func() {
|
|
for i := 1; i < 20; i++ {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(i), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
}
|
|
err := handler.ReceivedStopWaiting(&frames.StopWaitingFrame{LeastUnacked: protocol.PacketNumber(12)})
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ignorePacketsBelow).To(Equal(protocol.PacketNumber(11)))
|
|
})
|
|
|
|
It("does not decrease the ignorePacketsBelow number when an out-of-order StopWaiting arrives", func() {
|
|
err := handler.ReceivedStopWaiting(&frames.StopWaitingFrame{LeastUnacked: protocol.PacketNumber(12)})
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ignorePacketsBelow).To(Equal(protocol.PacketNumber(11)))
|
|
err = handler.ReceivedStopWaiting(&frames.StopWaitingFrame{LeastUnacked: protocol.PacketNumber(6)})
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ignorePacketsBelow).To(Equal(protocol.PacketNumber(11)))
|
|
})
|
|
})
|
|
|
|
Context("ACKs", func() {
|
|
Context("queueing ACKs", func() {
|
|
receiveAndAck10Packets := func() {
|
|
for i := 1; i <= 10; i++ {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(i), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
}
|
|
Expect(handler.GetAckFrame()).ToNot(BeNil())
|
|
Expect(handler.ackQueued).To(BeFalse())
|
|
ackAlarmCallbackCalled = false
|
|
}
|
|
|
|
It("always queues an ACK for the first packet", func() {
|
|
err := handler.ReceivedPacket(1, false)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ackQueued).To(BeTrue())
|
|
Expect(ackAlarmCallbackCalled).To(BeFalse())
|
|
})
|
|
|
|
It("only queues one ACK for many non-retransmittable packets", func() {
|
|
receiveAndAck10Packets()
|
|
for i := 11; i < 10+protocol.MaxPacketsReceivedBeforeAckSend; i++ {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(i), false)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ackQueued).To(BeFalse())
|
|
}
|
|
err := handler.ReceivedPacket(10+protocol.MaxPacketsReceivedBeforeAckSend, false)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ackQueued).To(BeTrue())
|
|
Expect(ackAlarmCallbackCalled).To(BeFalse())
|
|
})
|
|
|
|
It("queues an ACK for every second retransmittable packet, if they are arriving fast", func() {
|
|
receiveAndAck10Packets()
|
|
err := handler.ReceivedPacket(11, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ackQueued).To(BeFalse())
|
|
Expect(ackAlarmCallbackCalled).To(BeTrue())
|
|
ackAlarmCallbackCalled = false
|
|
err = handler.ReceivedPacket(12, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ackQueued).To(BeTrue())
|
|
Expect(ackAlarmCallbackCalled).To(BeFalse())
|
|
})
|
|
|
|
It("only sets the timer when receiving a retransmittable packets", func() {
|
|
receiveAndAck10Packets()
|
|
err := handler.ReceivedPacket(11, false)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ackQueued).To(BeFalse())
|
|
Expect(handler.ackAlarm).To(BeZero())
|
|
err = handler.ReceivedPacket(12, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ackQueued).To(BeFalse())
|
|
Expect(handler.ackAlarm).ToNot(BeZero())
|
|
Expect(ackAlarmCallbackCalled).To(BeTrue())
|
|
})
|
|
|
|
It("queues an ACK if it was reported missing before", func() {
|
|
receiveAndAck10Packets()
|
|
err := handler.ReceivedPacket(11, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedPacket(13, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
ack := handler.GetAckFrame() // ACK: 1 and 3, missing: 2
|
|
Expect(ack).ToNot(BeNil())
|
|
Expect(ack.HasMissingRanges()).To(BeTrue())
|
|
Expect(handler.ackQueued).To(BeFalse())
|
|
err = handler.ReceivedPacket(12, false)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
Expect(handler.ackQueued).To(BeTrue())
|
|
})
|
|
|
|
It("queues an ACK if it creates a new missing range", func() {
|
|
receiveAndAck10Packets()
|
|
for i := 11; i < 16; i++ {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(i), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
}
|
|
Expect(handler.GetAckFrame()).ToNot(BeNil())
|
|
handler.ReceivedPacket(20, true) // we now know that packets 16 to 19 are missing
|
|
Expect(handler.ackQueued).To(BeTrue())
|
|
})
|
|
})
|
|
|
|
Context("ACK generation", func() {
|
|
BeforeEach(func() {
|
|
handler.ackQueued = true
|
|
})
|
|
|
|
It("generates a simple ACK frame", func() {
|
|
err := handler.ReceivedPacket(1, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedPacket(2, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
ack := handler.GetAckFrame()
|
|
Expect(ack).ToNot(BeNil())
|
|
Expect(ack.LargestAcked).To(Equal(protocol.PacketNumber(2)))
|
|
Expect(ack.LowestAcked).To(Equal(protocol.PacketNumber(1)))
|
|
Expect(ack.AckRanges).To(BeEmpty())
|
|
})
|
|
|
|
It("saves the last sent ACK", func() {
|
|
err := handler.ReceivedPacket(1, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
ack := handler.GetAckFrame()
|
|
Expect(ack).ToNot(BeNil())
|
|
Expect(handler.lastAck).To(Equal(ack))
|
|
err = handler.ReceivedPacket(2, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
handler.ackQueued = true
|
|
ack = handler.GetAckFrame()
|
|
Expect(ack).ToNot(BeNil())
|
|
Expect(handler.lastAck).To(Equal(ack))
|
|
})
|
|
|
|
It("generates an ACK frame with missing packets", func() {
|
|
err := handler.ReceivedPacket(1, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
err = handler.ReceivedPacket(4, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
ack := handler.GetAckFrame()
|
|
Expect(ack).ToNot(BeNil())
|
|
Expect(ack.LargestAcked).To(Equal(protocol.PacketNumber(4)))
|
|
Expect(ack.LowestAcked).To(Equal(protocol.PacketNumber(1)))
|
|
Expect(ack.AckRanges).To(HaveLen(2))
|
|
Expect(ack.AckRanges[0]).To(Equal(frames.AckRange{FirstPacketNumber: 4, LastPacketNumber: 4}))
|
|
Expect(ack.AckRanges[1]).To(Equal(frames.AckRange{FirstPacketNumber: 1, LastPacketNumber: 1}))
|
|
})
|
|
|
|
It("deletes packets from the packetHistory after receiving a StopWaiting, after continuously received packets", func() {
|
|
for i := 1; i <= 12; i++ {
|
|
err := handler.ReceivedPacket(protocol.PacketNumber(i), true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
}
|
|
err := handler.ReceivedStopWaiting(&frames.StopWaitingFrame{LeastUnacked: protocol.PacketNumber(6)})
|
|
Expect(err).ToNot(HaveOccurred())
|
|
// check that the packets were deleted from the receivedPacketHistory by checking the values in an ACK frame
|
|
ack := handler.GetAckFrame()
|
|
Expect(ack).ToNot(BeNil())
|
|
Expect(ack.LargestAcked).To(Equal(protocol.PacketNumber(12)))
|
|
Expect(ack.LowestAcked).To(Equal(protocol.PacketNumber(6)))
|
|
Expect(ack.HasMissingRanges()).To(BeFalse())
|
|
})
|
|
|
|
It("resets all counters needed for the ACK queueing decision when sending an ACK", func() {
|
|
err := handler.ReceivedPacket(1, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
handler.ackAlarm = time.Now().Add(-time.Minute)
|
|
Expect(handler.GetAckFrame()).ToNot(BeNil())
|
|
Expect(handler.packetsReceivedSinceLastAck).To(BeZero())
|
|
Expect(handler.ackAlarm).To(BeZero())
|
|
Expect(handler.retransmittablePacketsReceivedSinceLastAck).To(BeZero())
|
|
Expect(handler.ackQueued).To(BeFalse())
|
|
})
|
|
|
|
It("doesn't generate an ACK when none is queued and the timer is not set", func() {
|
|
err := handler.ReceivedPacket(1, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
handler.ackQueued = false
|
|
handler.ackAlarm = time.Time{}
|
|
Expect(handler.GetAckFrame()).To(BeNil())
|
|
})
|
|
|
|
It("doesn't generate an ACK when none is queued and the timer has not yet expired", func() {
|
|
err := handler.ReceivedPacket(1, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
handler.ackQueued = false
|
|
handler.ackAlarm = time.Now().Add(time.Minute)
|
|
Expect(handler.GetAckFrame()).To(BeNil())
|
|
})
|
|
|
|
It("generates an ACK when the timer has expired", func() {
|
|
err := handler.ReceivedPacket(1, true)
|
|
Expect(err).ToNot(HaveOccurred())
|
|
handler.ackQueued = false
|
|
handler.ackAlarm = time.Now().Add(-time.Minute)
|
|
Expect(handler.GetAckFrame()).ToNot(BeNil())
|
|
})
|
|
})
|
|
})
|
|
})
|