uquic/internal/wire/ack_frame_test.go

368 lines
12 KiB
Go

package wire
import (
"bytes"
"io"
"time"
"github.com/lucas-clemente/quic-go/internal/protocol"
. "github.com/onsi/ginkgo"
. "github.com/onsi/gomega"
)
var _ = Describe("ACK Frame (for IETF QUIC)", func() {
Context("parsing", func() {
It("parses an ACK frame without any ranges", func() {
data := []byte{0xd}
data = append(data, encodeVarInt(100)...) // largest acked
data = append(data, encodeVarInt(0)...) // delay
data = append(data, encodeVarInt(0)...) // num blocks
data = append(data, encodeVarInt(10)...) // first ack block
b := bytes.NewReader(data)
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame.LargestAcked()).To(Equal(protocol.PacketNumber(100)))
Expect(frame.LowestAcked()).To(Equal(protocol.PacketNumber(90)))
Expect(frame.HasMissingRanges()).To(BeFalse())
Expect(b.Len()).To(BeZero())
})
It("parses an ACK frame that only acks a single packet", func() {
data := []byte{0xd}
data = append(data, encodeVarInt(55)...) // largest acked
data = append(data, encodeVarInt(0)...) // delay
data = append(data, encodeVarInt(0)...) // num blocks
data = append(data, encodeVarInt(0)...) // first ack block
b := bytes.NewReader(data)
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame.LargestAcked()).To(Equal(protocol.PacketNumber(55)))
Expect(frame.LowestAcked()).To(Equal(protocol.PacketNumber(55)))
Expect(frame.HasMissingRanges()).To(BeFalse())
Expect(b.Len()).To(BeZero())
})
It("accepts an ACK frame that acks all packets from 0 to largest", func() {
data := []byte{0xd}
data = append(data, encodeVarInt(20)...) // largest acked
data = append(data, encodeVarInt(0)...) // delay
data = append(data, encodeVarInt(0)...) // num blocks
data = append(data, encodeVarInt(20)...) // first ack block
b := bytes.NewReader(data)
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame.LargestAcked()).To(Equal(protocol.PacketNumber(20)))
Expect(frame.LowestAcked()).To(Equal(protocol.PacketNumber(0)))
Expect(frame.HasMissingRanges()).To(BeFalse())
Expect(b.Len()).To(BeZero())
})
It("rejects an ACK frame that has a first ACK block which is larger than LargestAcked", func() {
data := []byte{0xd}
data = append(data, encodeVarInt(20)...) // largest acked
data = append(data, encodeVarInt(0)...) // delay
data = append(data, encodeVarInt(0)...) // num blocks
data = append(data, encodeVarInt(21)...) // first ack block
b := bytes.NewReader(data)
_, err := parseAckFrame(b, versionIETFFrames)
Expect(err).To(MatchError("invalid first ACK range"))
})
It("parses an ACK frame that has a single block", func() {
data := []byte{0xd}
data = append(data, encodeVarInt(1000)...) // largest acked
data = append(data, encodeVarInt(0)...) // delay
data = append(data, encodeVarInt(1)...) // num blocks
data = append(data, encodeVarInt(100)...) // first ack block
data = append(data, encodeVarInt(98)...) // gap
data = append(data, encodeVarInt(50)...) // ack block
b := bytes.NewReader(data)
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame.LargestAcked()).To(Equal(protocol.PacketNumber(1000)))
Expect(frame.LowestAcked()).To(Equal(protocol.PacketNumber(750)))
Expect(frame.HasMissingRanges()).To(BeTrue())
Expect(frame.AckRanges).To(Equal([]AckRange{
{Largest: 1000, Smallest: 900},
{Largest: 800, Smallest: 750},
}))
Expect(b.Len()).To(BeZero())
})
It("parses an ACK frame that has a multiple blocks", func() {
data := []byte{0xd}
data = append(data, encodeVarInt(100)...) // largest acked
data = append(data, encodeVarInt(0)...) // delay
data = append(data, encodeVarInt(2)...) // num blocks
data = append(data, encodeVarInt(0)...) // first ack block
data = append(data, encodeVarInt(0)...) // gap
data = append(data, encodeVarInt(0)...) // ack block
data = append(data, encodeVarInt(1)...) // gap
data = append(data, encodeVarInt(1)...) // ack block
b := bytes.NewReader(data)
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame.LargestAcked()).To(Equal(protocol.PacketNumber(100)))
Expect(frame.LowestAcked()).To(Equal(protocol.PacketNumber(94)))
Expect(frame.HasMissingRanges()).To(BeTrue())
Expect(frame.AckRanges).To(Equal([]AckRange{
{Largest: 100, Smallest: 100},
{Largest: 98, Smallest: 98},
{Largest: 95, Smallest: 94},
}))
Expect(b.Len()).To(BeZero())
})
It("errors on EOF", func() {
data := []byte{0xd}
data = append(data, encodeVarInt(1000)...) // largest acked
data = append(data, encodeVarInt(0)...) // delay
data = append(data, encodeVarInt(1)...) // num blocks
data = append(data, encodeVarInt(100)...) // first ack block
data = append(data, encodeVarInt(98)...) // gap
data = append(data, encodeVarInt(50)...) // ack block
_, err := parseAckFrame(bytes.NewReader(data), versionIETFFrames)
Expect(err).NotTo(HaveOccurred())
for i := range data {
_, err := parseAckFrame(bytes.NewReader(data[0:i]), versionIETFFrames)
Expect(err).To(MatchError(io.EOF))
}
})
})
Context("when writing", func() {
It("writes a simple frame", func() {
buf := &bytes.Buffer{}
f := &AckFrame{
AckRanges: []AckRange{{Smallest: 100, Largest: 1337}},
}
err := f.Write(buf, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
expected := []byte{0xd}
expected = append(expected, encodeVarInt(1337)...) // largest acked
expected = append(expected, 0) // delay
expected = append(expected, encodeVarInt(0)...) // num ranges
expected = append(expected, encodeVarInt(1337-100)...)
Expect(buf.Bytes()).To(Equal(expected))
})
It("writes a frame that acks a single packet", func() {
buf := &bytes.Buffer{}
f := &AckFrame{
AckRanges: []AckRange{{Smallest: 0xdeadbeef, Largest: 0xdeadbeef}},
DelayTime: 18 * time.Millisecond,
}
err := f.Write(buf, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(f.Length(versionIETFFrames)).To(BeEquivalentTo(buf.Len()))
b := bytes.NewReader(buf.Bytes())
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame).To(Equal(f))
Expect(frame.HasMissingRanges()).To(BeFalse())
Expect(frame.DelayTime).To(Equal(f.DelayTime))
Expect(b.Len()).To(BeZero())
})
It("writes a frame that acks many packets", func() {
buf := &bytes.Buffer{}
f := &AckFrame{
AckRanges: []AckRange{{Smallest: 0x1337, Largest: 0xdeadbeef}},
}
err := f.Write(buf, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(f.Length(versionIETFFrames)).To(BeEquivalentTo(buf.Len()))
b := bytes.NewReader(buf.Bytes())
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame).To(Equal(f))
Expect(frame.HasMissingRanges()).To(BeFalse())
Expect(b.Len()).To(BeZero())
})
It("writes a frame with a a single gap", func() {
buf := &bytes.Buffer{}
f := &AckFrame{
AckRanges: []AckRange{
{Smallest: 400, Largest: 1000},
{Smallest: 100, Largest: 200},
},
}
Expect(f.validateAckRanges()).To(BeTrue())
err := f.Write(buf, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(f.Length(versionIETFFrames)).To(BeEquivalentTo(buf.Len()))
b := bytes.NewReader(buf.Bytes())
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame).To(Equal(f))
Expect(frame.HasMissingRanges()).To(BeTrue())
Expect(b.Len()).To(BeZero())
})
It("writes a frame with multiple ranges", func() {
buf := &bytes.Buffer{}
f := &AckFrame{
AckRanges: []AckRange{
{Smallest: 10, Largest: 10},
{Smallest: 8, Largest: 8},
{Smallest: 5, Largest: 6},
{Smallest: 1, Largest: 3},
},
}
Expect(f.validateAckRanges()).To(BeTrue())
err := f.Write(buf, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(f.Length(versionIETFFrames)).To(BeEquivalentTo(buf.Len()))
b := bytes.NewReader(buf.Bytes())
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame).To(Equal(f))
Expect(frame.HasMissingRanges()).To(BeTrue())
Expect(b.Len()).To(BeZero())
})
It("limits the maximum size of the ACK frame", func() {
buf := &bytes.Buffer{}
const numRanges = 1000
ackRanges := make([]AckRange, numRanges)
for i := protocol.PacketNumber(1); i <= numRanges; i++ {
ackRanges[numRanges-i] = AckRange{Smallest: 2 * i, Largest: 2 * i}
}
f := &AckFrame{AckRanges: ackRanges}
Expect(f.validateAckRanges()).To(BeTrue())
err := f.Write(buf, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(f.Length(versionIETFFrames)).To(BeEquivalentTo(buf.Len()))
// make sure the ACK frame is *a little bit* smaller than the MaxAckFrameSize
Expect(buf.Len()).To(BeNumerically(">", protocol.MaxAckFrameSize-5))
Expect(buf.Len()).To(BeNumerically("<=", protocol.MaxAckFrameSize))
b := bytes.NewReader(buf.Bytes())
frame, err := parseAckFrame(b, versionIETFFrames)
Expect(err).ToNot(HaveOccurred())
Expect(frame.HasMissingRanges()).To(BeTrue())
Expect(b.Len()).To(BeZero())
Expect(len(frame.AckRanges)).To(BeNumerically("<", numRanges)) // make sure we dropped some ranges
})
})
Context("ACK range validator", func() {
It("rejects ACKs without ranges", func() {
Expect((&AckFrame{}).validateAckRanges()).To(BeFalse())
})
It("accepts an ACK without NACK Ranges", func() {
ack := AckFrame{
AckRanges: []AckRange{{Smallest: 1, Largest: 7}},
}
Expect(ack.validateAckRanges()).To(BeTrue())
})
It("rejects ACK ranges with Smallest greater than Largest", func() {
ack := AckFrame{
AckRanges: []AckRange{
{Smallest: 8, Largest: 10},
{Smallest: 4, Largest: 3},
},
}
Expect(ack.validateAckRanges()).To(BeFalse())
})
It("rejects ACK ranges in the wrong order", func() {
ack := AckFrame{
AckRanges: []AckRange{
{Smallest: 2, Largest: 2},
{Smallest: 6, Largest: 7},
},
}
Expect(ack.validateAckRanges()).To(BeFalse())
})
It("rejects with overlapping ACK ranges", func() {
ack := AckFrame{
AckRanges: []AckRange{
{Smallest: 5, Largest: 7},
{Smallest: 2, Largest: 5},
},
}
Expect(ack.validateAckRanges()).To(BeFalse())
})
It("rejects ACK ranges that are part of a larger ACK range", func() {
ack := AckFrame{
AckRanges: []AckRange{
{Smallest: 4, Largest: 7},
{Smallest: 5, Largest: 6},
},
}
Expect(ack.validateAckRanges()).To(BeFalse())
})
It("rejects with directly adjacent ACK ranges", func() {
ack := AckFrame{
AckRanges: []AckRange{
{Smallest: 5, Largest: 7},
{Smallest: 2, Largest: 4},
},
}
Expect(ack.validateAckRanges()).To(BeFalse())
})
It("accepts an ACK with one lost packet", func() {
ack := AckFrame{
AckRanges: []AckRange{
{Smallest: 5, Largest: 10},
{Smallest: 1, Largest: 3},
},
}
Expect(ack.validateAckRanges()).To(BeTrue())
})
It("accepts an ACK with multiple lost packets", func() {
ack := AckFrame{
AckRanges: []AckRange{
{Smallest: 15, Largest: 20},
{Smallest: 10, Largest: 12},
{Smallest: 1, Largest: 3},
},
}
Expect(ack.validateAckRanges()).To(BeTrue())
})
})
Context("check if ACK frame acks a certain packet", func() {
It("works with an ACK without any ranges", func() {
f := AckFrame{
AckRanges: []AckRange{{Smallest: 5, Largest: 10}},
}
Expect(f.AcksPacket(1)).To(BeFalse())
Expect(f.AcksPacket(4)).To(BeFalse())
Expect(f.AcksPacket(5)).To(BeTrue())
Expect(f.AcksPacket(8)).To(BeTrue())
Expect(f.AcksPacket(10)).To(BeTrue())
Expect(f.AcksPacket(11)).To(BeFalse())
Expect(f.AcksPacket(20)).To(BeFalse())
})
It("works with an ACK with multiple ACK ranges", func() {
f := AckFrame{
AckRanges: []AckRange{
{Smallest: 15, Largest: 20},
{Smallest: 5, Largest: 8},
},
}
Expect(f.AcksPacket(4)).To(BeFalse())
Expect(f.AcksPacket(5)).To(BeTrue())
Expect(f.AcksPacket(6)).To(BeTrue())
Expect(f.AcksPacket(7)).To(BeTrue())
Expect(f.AcksPacket(8)).To(BeTrue())
Expect(f.AcksPacket(9)).To(BeFalse())
Expect(f.AcksPacket(14)).To(BeFalse())
Expect(f.AcksPacket(15)).To(BeTrue())
Expect(f.AcksPacket(18)).To(BeTrue())
Expect(f.AcksPacket(19)).To(BeTrue())
Expect(f.AcksPacket(20)).To(BeTrue())
Expect(f.AcksPacket(21)).To(BeFalse())
})
})
})