cloudflared-mirror/packet/packet_test.go

105 lines
2.7 KiB
Go

package packet
import (
"bytes"
"net/netip"
"testing"
"github.com/google/gopacket/layers"
"github.com/stretchr/testify/require"
"golang.org/x/net/icmp"
"golang.org/x/net/ipv4"
"golang.org/x/net/ipv6"
)
func TestNewICMPTTLExceedPacket(t *testing.T) {
ipv4Packet := IP{
Src: netip.MustParseAddr("192.168.1.1"),
Dst: netip.MustParseAddr("10.0.0.1"),
Protocol: layers.IPProtocolICMPv4,
TTL: 0,
}
icmpV4Packet := ICMP{
IP: &ipv4Packet,
Message: &icmp.Message{
Type: ipv4.ICMPTypeEcho,
Code: 0,
Body: &icmp.Echo{
ID: 25821,
Seq: 58129,
Data: []byte("test ttl=0"),
},
},
}
assertTTLExceedPacket(t, &icmpV4Packet)
icmpV4Packet.Body = &icmp.Echo{
ID: 3487,
Seq: 19183,
Data: make([]byte, ipv4MinMTU),
}
assertTTLExceedPacket(t, &icmpV4Packet)
ipv6Packet := IP{
Src: netip.MustParseAddr("fd51:2391:523:f4ee::1"),
Dst: netip.MustParseAddr("fd51:2391:697:f4ee::2"),
Protocol: layers.IPProtocolICMPv6,
TTL: 0,
}
icmpV6Packet := ICMP{
IP: &ipv6Packet,
Message: &icmp.Message{
Type: ipv6.ICMPTypeEchoRequest,
Code: 0,
Body: &icmp.Echo{
ID: 25821,
Seq: 58129,
Data: []byte("test ttl=0"),
},
},
}
assertTTLExceedPacket(t, &icmpV6Packet)
icmpV6Packet.Body = &icmp.Echo{
ID: 1497,
Seq: 39284,
Data: make([]byte, ipv6MinMTU),
}
assertTTLExceedPacket(t, &icmpV6Packet)
}
func assertTTLExceedPacket(t *testing.T, pk *ICMP) {
encoder := NewEncoder()
rawPacket, err := encoder.Encode(pk)
require.NoError(t, err)
minMTU := ipv4MinMTU
headerLen := ipv4MinHeaderLen
routerIP := netip.MustParseAddr("172.16.0.3")
if pk.Dst.Is6() {
minMTU = ipv6MinMTU
headerLen = ipv6HeaderLen
routerIP = netip.MustParseAddr("fd51:2391:697:f4ee::3")
}
ttlExceedPacket := NewICMPTTLExceedPacket(pk.IP, rawPacket, routerIP)
require.Equal(t, routerIP, ttlExceedPacket.Src)
require.Equal(t, pk.Src, ttlExceedPacket.Dst)
require.Equal(t, pk.Protocol, ttlExceedPacket.Protocol)
require.Equal(t, DefaultTTL, ttlExceedPacket.TTL)
timeExceed, ok := ttlExceedPacket.Body.(*icmp.TimeExceeded)
require.True(t, ok)
if len(rawPacket.Data) > minMTU {
require.True(t, bytes.Equal(timeExceed.Data, rawPacket.Data[:minMTU-headerLen-icmpHeaderLen]))
} else {
require.True(t, bytes.Equal(timeExceed.Data, rawPacket.Data))
}
rawTTLExceedPacket, err := encoder.Encode(ttlExceedPacket)
require.NoError(t, err)
if len(rawPacket.Data) > minMTU {
require.Len(t, rawTTLExceedPacket.Data, minMTU)
} else {
require.Len(t, rawTTLExceedPacket.Data, headerLen+icmpHeaderLen+len(rawPacket.Data))
require.True(t, bytes.Equal(rawPacket.Data, rawTTLExceedPacket.Data[headerLen+icmpHeaderLen:]))
}
}