github.com/mikelsr/quic-go@v0.36.1-0.20230701132136-1d9415b66898/internal/wire/version_negotiation_test.go (about)

     1  package wire
     2  
     3  import (
     4  	"encoding/binary"
     5  	mrand "math/rand"
     6  
     7  	"golang.org/x/exp/rand"
     8  
     9  	"github.com/mikelsr/quic-go/internal/protocol"
    10  
    11  	. "github.com/onsi/ginkgo/v2"
    12  	. "github.com/onsi/gomega"
    13  )
    14  
    15  var _ = Describe("Version Negotiation Packets", func() {
    16  	randConnID := func(l int) protocol.ArbitraryLenConnectionID {
    17  		b := make(protocol.ArbitraryLenConnectionID, l)
    18  		_, err := mrand.Read(b)
    19  		Expect(err).ToNot(HaveOccurred())
    20  		return b
    21  	}
    22  
    23  	It("parses a Version Negotiation packet", func() {
    24  		srcConnID := randConnID(rand.Intn(255) + 1)
    25  		destConnID := randConnID(rand.Intn(255) + 1)
    26  		versions := []protocol.VersionNumber{0x22334455, 0x33445566}
    27  		data := []byte{0x80, 0, 0, 0, 0}
    28  		data = append(data, uint8(len(destConnID)))
    29  		data = append(data, destConnID...)
    30  		data = append(data, uint8(len(srcConnID)))
    31  		data = append(data, srcConnID...)
    32  		for _, v := range versions {
    33  			data = append(data, []byte{0, 0, 0, 0}...)
    34  			binary.BigEndian.PutUint32(data[len(data)-4:], uint32(v))
    35  		}
    36  		Expect(IsVersionNegotiationPacket(data)).To(BeTrue())
    37  		dest, src, supportedVersions, err := ParseVersionNegotiationPacket(data)
    38  		Expect(err).ToNot(HaveOccurred())
    39  		Expect(dest).To(Equal(destConnID))
    40  		Expect(src).To(Equal(srcConnID))
    41  		Expect(supportedVersions).To(Equal(versions))
    42  	})
    43  
    44  	It("errors if it contains versions of the wrong length", func() {
    45  		connID := protocol.ArbitraryLenConnectionID{1, 2, 3, 4, 5, 6, 7, 8}
    46  		versions := []protocol.VersionNumber{0x22334455, 0x33445566}
    47  		data := ComposeVersionNegotiation(connID, connID, versions)
    48  		_, _, _, err := ParseVersionNegotiationPacket(data[:len(data)-2])
    49  		Expect(err).To(MatchError("Version Negotiation packet has a version list with an invalid length"))
    50  	})
    51  
    52  	It("errors if the version list is empty", func() {
    53  		connID := protocol.ArbitraryLenConnectionID{1, 2, 3, 4, 5, 6, 7, 8}
    54  		versions := []protocol.VersionNumber{0x22334455}
    55  		data := ComposeVersionNegotiation(connID, connID, versions)
    56  		// remove 8 bytes (two versions), since ComposeVersionNegotiation also added a reserved version number
    57  		data = data[:len(data)-8]
    58  		_, _, _, err := ParseVersionNegotiationPacket(data)
    59  		Expect(err).To(MatchError("Version Negotiation packet has empty version list"))
    60  	})
    61  
    62  	It("adds a reserved version", func() {
    63  		srcConnID := protocol.ArbitraryLenConnectionID{0xde, 0xad, 0xbe, 0xef, 0xca, 0xfe, 0x13, 0x37}
    64  		destConnID := protocol.ArbitraryLenConnectionID{1, 2, 3, 4, 5, 6, 7, 8}
    65  		versions := []protocol.VersionNumber{1001, 1003}
    66  		data := ComposeVersionNegotiation(destConnID, srcConnID, versions)
    67  		Expect(IsLongHeaderPacket(data[0])).To(BeTrue())
    68  		v, err := ParseVersion(data)
    69  		Expect(err).ToNot(HaveOccurred())
    70  		Expect(v).To(BeZero())
    71  		dest, src, supportedVersions, err := ParseVersionNegotiationPacket(data)
    72  		Expect(err).ToNot(HaveOccurred())
    73  		Expect(dest).To(Equal(destConnID))
    74  		Expect(src).To(Equal(srcConnID))
    75  		// the supported versions should include one reserved version number
    76  		Expect(supportedVersions).To(HaveLen(len(versions) + 1))
    77  		for _, v := range versions {
    78  			Expect(supportedVersions).To(ContainElement(v))
    79  		}
    80  		var reservedVersion protocol.VersionNumber
    81  	versionLoop:
    82  		for _, ver := range supportedVersions {
    83  			for _, v := range versions {
    84  				if v == ver {
    85  					continue versionLoop
    86  				}
    87  			}
    88  			reservedVersion = ver
    89  		}
    90  		Expect(reservedVersion).ToNot(BeZero())
    91  		Expect(reservedVersion&0x0f0f0f0f == 0x0a0a0a0a).To(BeTrue()) // check that it's a greased version number
    92  	})
    93  })