update_sender_test.go

	tests := []struct {
		Name     string
		Prefix   bnet.Prefix
		Expected []byte
	}{
		{
			Name:   "IPv6 MP_UNREACH_NLRI",
			Prefix: bnet.NewPfx(bnet.IPv6FromBlocks(0x2804, 0x148c, 0, 0, 0, 0, 0, 0), 32),
			Expected: []byte{
				0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, // BGP Marker
				0x00, 0x22, // BGP Message Length
				0x02,       // BGP Message Type == Update
				0x00, 0x00, // WithDraw Octet length
				0x00, 0x0b, // Length
				0x80,       // Flags
				0x0f,       // Attribute Code
				0x08,       // Attribute length
				0x00, 0x02, // AFI
				0x01,                         // SAFI
				0x20, 0x28, 0x04, 0x14, 0x8c, // Prefix
			},
		},
	}
	for _, test := range tests {
		t.Run(test.Name, func(t *testing.T) {
			buf := bytes.NewBuffer([]byte{})

			u := &UpdateSender{
				fsm: &FSM{
					supportsMultiProtocol: true,
				},
				afi:     packet.IPv6AFI,
				safi:    packet.UnicastSAFI,
				options: &packet.EncodeOptions{},
			}

			err := u.withDrawPrefixesMultiProtocol(buf, test.Prefix, &route.Path{})
			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}

			assert.Equal(t, test.Expected, buf.Bytes())
		})
	}
}

func TestWithDrawPrefixesAddPath(t *testing.T) {
	testcases := []struct {
		Name          string
		Prefix        bnet.Prefix
		Path          *route.Path
		Expected      []byte
		ExpectedError error
	}{
		{
			Name:   "Normal withdraw",
			Prefix: bnet.NewPfx(bnet.IPv4(1413010532), 24),
			Path: &route.Path{
				Type: route.BGPPathType,
				BGPPath: &route.BGPPath{
					PathIdentifier: 1,
				},
			},
			Expected: []byte{
				0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, // BGP Marker
				0x00, 0x1f, // BGP Message Length
				0x02,       // BGP Message Type == Update
				0x00, 0x08, // WithDraw Octet length
				0x00, 0x00, 0x00, 0x01, // NLRI Path Identifier
				0x18,             // Prefix Length
				0x54, 0x38, 0xd4, // Prefix,
				0x00, 0x00, // Total Path Attribute Length
			},
			ExpectedError: nil,
		},
		{
			Name:   "Non bgp withdraw",
			Prefix: bnet.NewPfx(bnet.IPv4(1413010532), 24),
			Path: &route.Path{
				Type: route.StaticPathType,
			},
			Expected:      []byte{},
			ExpectedError: errors.New("wrong path type, expected BGPPathType"),
		},
		{
			Name:   "Nil BGPPathType",
			Prefix: bnet.NewPfx(bnet.IPv4(1413010532), 24),
			Path: &route.Path{
				Type: route.BGPPathType,
			},
			Expected:      []byte{},
			ExpectedError: errors.New("got nil BGPPath"),
		},
	}
	for _, tc := range testcases {
		buf := bytes.NewBuffer([]byte{})

		u := &UpdateSender{
			fsm: &FSM{},
			options: &packet.EncodeOptions{
				UseAddPath: true,
			},
		}

		err := u.withDrawPrefixesAddPath(buf, tc.Prefix, tc.Path)
		assert.Equal(t, tc.ExpectedError, err, "error mismatch in testcase %v", tc.Name)
		assert.Equal(t, tc.Expected, buf.Bytes(), "expected different bytes in testcase %v", tc.Name)
	}
}