Function TestDNSPacketWriteAnswer

layers/dns_test.go:1095–1130

(t *testing.T)

}

func TestDNSPacketWriteAnswer(t *testing.T) {
	dns := &DNS{ID: 0x1234, QR: true, OpCode: DNSOpCodeQuery, ResponseCode: DNSResponseCodeNoErr, Answers: []DNSResourceRecord{
		DNSResourceRecord{
			Name:  []byte("www.example.com"),
			Type:  DNSTypeA,
			Class: DNSClassIN,
			IP:    net.IPv4(127, 0, 0, 1),
		},
		DNSResourceRecord{
			Name:  []byte("www.example.com"),
			Type:  DNSTypeAAAA,
			Class: DNSClassIN,
			IP:    net.IP{15: 1},
		},
	}}
	buf := gopacket.NewSerializeBuffer()
	opts := gopacket.SerializeOptions{ComputeChecksums: true, FixLengths: true}
	if err := gopacket.SerializeLayers(buf, opts, dns); err != nil {
		t.Fatal(err)
	}
	dns2 := &DNS{}
	if err := dns2.DecodeFromBytes(buf.Bytes(), gopacket.NilDecodeFeedback); err != nil {
		t.Fatalf("could not decode: %v", err)
	}
	if want, got := 2, len(dns2.Answers); want != got {
		t.Fatalf("num answers, want %d got %d", want, got)
	} else if got, want := string(dns2.Answers[0].Name), "www.example.com"; got != want {
		t.Fatalf("unexpected first answer name %q, want %q", got, want)
	} else if got, want := string(dns2.Answers[1].Name), "www.example.com"; got != want {
		t.Fatalf("unexpected second answer name %q, want %q", got, want)
	}
	t.Log(gopacket.LayerString(dns2))
	if want, got := 86, len(buf.Bytes()); want != got {
		t.Fatalf("Encoded size, want %d got %d", want, got)
	}
}