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|
package arp
import (
"bytes"
"errors"
"io"
"net"
"testing"
)
func TestClientRequestNoIPv4Address(t *testing.T) {
c := &Client{}
_, got := c.Resolve(net.IPv4zero)
if want := errNoIPv4Addr; want != got {
t.Fatalf("unexpected error for no IPv4 address:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestInvalidSourceHardwareAddr(t *testing.T) {
c := &Client{
ifi: &net.Interface{},
ip: net.IPv4zero,
}
_, got := c.Resolve(net.IPv4zero)
if want := ErrInvalidHardwareAddr; want != got {
t.Fatalf("unexpected error for invalid source hardware address:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestIPv6Address(t *testing.T) {
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0, 0, 0, 0, 0, 0},
},
ip: net.IPv4zero,
}
_, got := c.Resolve(net.IPv6loopback)
if want := ErrInvalidIP; want != got {
t.Fatalf("unexpected error for IPv6 address:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestErrWriteTo(t *testing.T) {
errWriteTo := errors.New("test error")
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0, 0, 0, 0, 0, 0},
},
ip: net.IPv4zero,
p: &errWriteToPacketConn{
err: errWriteTo,
},
}
_, got := c.Resolve(net.IPv4zero)
if want := errWriteTo; want != got {
t.Fatalf("unexpected error during WriteTo:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestErrReadFrom(t *testing.T) {
errReadFrom := errors.New("test error")
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0, 0, 0, 0, 0, 0},
},
ip: net.IPv4zero,
p: &errReadFromPacketConn{
err: errReadFrom,
},
}
_, got := c.Resolve(net.IPv4zero)
if want := errReadFrom; want != got {
t.Fatalf("unexpected error during ReadFrom:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestEthernetFrameUnexpectedEOF(t *testing.T) {
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0, 0, 0, 0, 0, 0},
},
ip: net.IPv4zero,
p: &bufferReadFromPacketConn{
b: bytes.NewBuffer([]byte{0}),
},
}
_, got := c.Resolve(net.IPv4zero)
if want := io.ErrUnexpectedEOF; want != got {
t.Fatalf("unexpected error while reading ethernet frame:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestEthernetFrameWrongDestinationHardwareAddr(t *testing.T) {
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0xde, 0xad, 0xbe, 0xef, 0xde, 0xad},
},
ip: net.IPv4zero,
p: &bufferReadFromPacketConn{
b: bytes.NewBuffer(append([]byte{
// Ethernet frame with wrong destination hardware address
0, 0, 0, 0, 0, 0, // Wrong destination
0, 0, 0, 0, 0, 0,
0x00, 0x00,
}, make([]byte, 46)...)),
},
}
_, got := c.Resolve(net.IPv4zero)
if want := io.EOF; want != got {
t.Fatalf("unexpected error while reading ethernet frame with wrong destination hardware address:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestEthernetFrameWrongEtherType(t *testing.T) {
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0, 0, 0, 0, 0, 0},
},
ip: net.IPv4zero,
p: &bufferReadFromPacketConn{
b: bytes.NewBuffer(append([]byte{
// Ethernet frame with non-ARP EtherType
0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0,
0x00, 0x00, // Wrong EtherType
}, make([]byte, 46)...)),
},
}
_, got := c.Resolve(net.IPv4zero)
if want := io.EOF; want != got {
t.Fatalf("unexpected error while reading ethernet frame with wrong EtherType:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestARPPacketUnexpectedEOF(t *testing.T) {
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0, 0, 0, 0, 0, 0},
},
ip: net.IPv4zero,
p: &bufferReadFromPacketConn{
b: bytes.NewBuffer(append([]byte{
// Ethernet frame
0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0,
0x08, 0x06,
// ARP packet with misleading hardware address length
0, 0,
0, 0,
255, 255, // Misleading hardware address length
}, make([]byte, 40)...)),
},
}
_, got := c.Resolve(net.IPv4zero)
if want := io.ErrUnexpectedEOF; want != got {
t.Fatalf("unexpected error while reading ARP packet:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestARPRequestInsteadOfResponse(t *testing.T) {
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0, 0, 0, 0, 0, 0},
},
ip: net.IPv4zero,
p: &bufferReadFromPacketConn{
b: bytes.NewBuffer(append([]byte{
// Ethernet frame
0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0,
0x08, 0x06,
// ARP request, not response
0, 1,
0x08, 0x06,
6,
4,
0, 1, // Request, not Response
0, 0, 0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0, 0, 0,
0, 0, 0, 0,
}, make([]byte, 46)...)),
},
}
_, got := c.Resolve(net.IPv4zero)
if want := io.EOF; want != got {
t.Fatalf("unexpected error while reading ARP response with wrong operation type:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestARPResponseWrongSenderIP(t *testing.T) {
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0, 0, 0, 0, 0, 0},
},
ip: net.IPv4(192, 168, 1, 1).To4(),
p: &bufferReadFromPacketConn{
b: bytes.NewBuffer(append([]byte{
// Ethernet frame
0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0,
0x08, 0x06,
// ARP Packet not bound for this IP address
0, 1,
0x08, 0x06,
6,
4,
0, 2,
0, 0, 0, 0, 0, 0,
192, 168, 1, 10, // Wrong IP address
0, 0, 0, 0, 0, 0,
192, 168, 1, 1,
}, make([]byte, 46)...)),
},
}
_, got := c.Resolve(net.IPv4zero)
if want := io.EOF; want != got {
t.Fatalf("unexpected error while reading ARP response with wrong sender IP:\n- want: %v\n- got: %v",
want, got)
}
}
func TestClientRequestOK(t *testing.T) {
c := &Client{
ifi: &net.Interface{
HardwareAddr: net.HardwareAddr{0xde, 0xad, 0xbe, 0xef, 0xde, 0xad},
},
ip: net.IPv4(192, 168, 1, 1).To4(),
p: &bufferReadFromPacketConn{
b: bytes.NewBuffer(append([]byte{
// Ethernet frame
0xde, 0xad, 0xbe, 0xef, 0xde, 0xad,
0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff,
0x08, 0x06,
// ARP Packet
0, 1,
0x08, 0x06,
6,
4,
0, 2,
0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff,
192, 168, 1, 10,
0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, // mac needn't match ours
192, 168, 1, 2, // ip needn't match ours
}, make([]byte, 40)...)),
},
}
wantHW := net.HardwareAddr{0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff}
gotHW, err := c.Resolve(net.IPv4(192, 168, 1, 10))
if err != nil {
t.Fatal(err)
}
if want, got := wantHW, gotHW; !bytes.Equal(want, got) {
t.Fatalf("unexpected hardware address for request:\n- want: %v\n- got: %v",
want, got)
}
}
// bufferReadFromPacketConn is a net.PacketConn which copies bytes from its
// embedded buffer into b when when its ReadFrom method is called.
type bufferReadFromPacketConn struct {
b *bytes.Buffer
noopPacketConn
}
func (p *bufferReadFromPacketConn) ReadFrom(b []byte) (int, net.Addr, error) {
n, err := p.b.Read(b)
return n, nil, err
}
// errWriteToPacketConn is a net.PacketConn which always returns its embedded
// error when its WriteTo method is called.
type errWriteToPacketConn struct {
err error
noopPacketConn
}
func (p *errWriteToPacketConn) WriteTo(b []byte, addr net.Addr) (int, error) { return 0, p.err }
// errReadFromPacketConn is a net.PacketConn which always returns its embedded
// error when its ReadFrom method is called.
type errReadFromPacketConn struct {
err error
noopPacketConn
}
func (p *errReadFromPacketConn) ReadFrom(b []byte) (int, net.Addr, error) { return 0, nil, p.err }
|
