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package dhcpv4
import (
"bytes"
"net"
"testing"
"github.com/insomniacslk/dhcp/iana"
"github.com/stretchr/testify/require"
"github.com/u-root/u-root/pkg/uio"
)
func TestGetExternalIPv4Addrs(t *testing.T) {
addrs4and6 := []net.Addr{
&net.IPAddr{IP: net.IP{1, 2, 3, 4}},
&net.IPAddr{IP: net.IP{4, 3, 2, 1}},
&net.IPNet{IP: net.IP{4, 3, 2, 0}},
&net.IPAddr{IP: net.IP{1, 2, 3, 4, 1, 1, 1, 1}},
&net.IPAddr{IP: net.IP{4, 3, 2, 1, 1, 1, 1, 1}},
&net.IPAddr{}, // nil IP
&net.IPAddr{IP: net.IP{127, 0, 0, 1}}, // loopback IP
}
expected := []net.IP{
net.IP{1, 2, 3, 4},
net.IP{4, 3, 2, 1},
net.IP{4, 3, 2, 0},
}
actual, err := GetExternalIPv4Addrs(addrs4and6)
require.NoError(t, err)
require.Equal(t, expected, actual)
}
func TestFromBytes(t *testing.T) {
data := []byte{
1, // dhcp request
1, // ethernet hw type
6, // hw addr length
3, // hop count
0xaa, 0xbb, 0xcc, 0xdd, // transaction ID, big endian (network)
0, 3, // number of seconds
0, 1, // broadcast
0, 0, 0, 0, // client IP address
0, 0, 0, 0, // your IP address
0, 0, 0, 0, // server IP address
0, 0, 0, 0, // gateway IP address
0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // client MAC address + padding
}
// server host name
expectedHostname := []byte{}
for i := 0; i < 64; i++ {
expectedHostname = append(expectedHostname, 0)
}
data = append(data, expectedHostname...)
// boot file name
expectedBootfilename := []byte{}
for i := 0; i < 128; i++ {
expectedBootfilename = append(expectedBootfilename, 0)
}
data = append(data, expectedBootfilename...)
// magic cookie, then no options
data = append(data, magicCookie[:]...)
d, err := FromBytes(data)
require.NoError(t, err)
require.Equal(t, d.OpCode, OpcodeBootRequest)
require.Equal(t, d.HWType, iana.HWTypeEthernet)
require.Equal(t, d.HopCount, byte(3))
require.Equal(t, d.TransactionID, TransactionID{0xaa, 0xbb, 0xcc, 0xdd})
require.Equal(t, d.NumSeconds, uint16(3))
require.Equal(t, d.Flags, uint16(1))
require.True(t, d.ClientIPAddr.Equal(net.IPv4zero))
require.True(t, d.YourIPAddr.Equal(net.IPv4zero))
require.True(t, d.GatewayIPAddr.Equal(net.IPv4zero))
require.Equal(t, d.ClientHWAddr, net.HardwareAddr{0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff})
require.Equal(t, d.ServerHostName, "")
require.Equal(t, d.BootFileName, "")
// no need to check Magic Cookie as it is already validated in FromBytes
// above
}
func TestFromBytesZeroLength(t *testing.T) {
data := []byte{}
_, err := FromBytes(data)
require.Error(t, err)
}
func TestFromBytesShortLength(t *testing.T) {
data := []byte{1, 1, 6, 0}
_, err := FromBytes(data)
require.Error(t, err)
}
func TestFromBytesInvalidOptions(t *testing.T) {
data := []byte{
1, // dhcp request
1, // ethernet hw type
6, // hw addr length
0, // hop count
0xaa, 0xbb, 0xcc, 0xdd, // transaction ID
3, 0, // number of seconds
1, 0, // broadcast
0, 0, 0, 0, // client IP address
0, 0, 0, 0, // your IP address
0, 0, 0, 0, // server IP address
0, 0, 0, 0, // gateway IP address
0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // client MAC address + padding
}
// server host name
for i := 0; i < 64; i++ {
data = append(data, 0)
}
// boot file name
for i := 0; i < 128; i++ {
data = append(data, 0)
}
// invalid magic cookie, forcing option parsing to fail
data = append(data, []byte{99, 130, 83, 98}...)
_, err := FromBytes(data)
require.Error(t, err)
}
func TestToStringMethods(t *testing.T) {
d, err := New()
if err != nil {
t.Fatal(err)
}
// FlagsToString
d.SetUnicast()
require.Equal(t, "Unicast", d.FlagsToString())
d.SetBroadcast()
require.Equal(t, "Broadcast", d.FlagsToString())
d.Flags = 0xffff
require.Equal(t, "Broadcast (reserved bits not zeroed)", d.FlagsToString())
}
func TestNewToBytes(t *testing.T) {
// the following bytes match what dhcpv4.New would create. Keep them in
// sync!
expected := []byte{
1, // Opcode BootRequest
1, // HwType Ethernet
6, // HwAddrLen
0, // HopCount
0x11, 0x22, 0x33, 0x44, // TransactionID
0, 0, // NumSeconds
0, 0, // Flags
0, 0, 0, 0, // ClientIPAddr
0, 0, 0, 0, // YourIPAddr
0, 0, 0, 0, // ServerIPAddr
0, 0, 0, 0, // GatewayIPAddr
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // ClientHwAddr
}
// ServerHostName
expected = append(expected, bytes.Repeat([]byte{0}, 64)...)
// BootFileName
expected = append(expected, bytes.Repeat([]byte{0}, 128)...)
// Magic Cookie
expected = append(expected, magicCookie[:]...)
// Minimum message length padding.
//
// 236 + 4 byte cookie + 59 bytes padding + 1 byte end.
expected = append(expected, bytes.Repeat([]byte{0}, 59)...)
// End
expected = append(expected, 0xff)
d, err := New()
require.NoError(t, err)
// fix TransactionID to match the expected one, since it's randomly
// generated in New()
d.TransactionID = TransactionID{0x11, 0x22, 0x33, 0x44}
got := d.ToBytes()
require.Equal(t, expected, got)
}
func TestGetOption(t *testing.T) {
d, err := New()
if err != nil {
t.Fatal(err)
}
hostnameOpt := OptGeneric(OptionHostName, []byte("darkstar"))
bootFileOpt := OptBootFileName("boot.img")
d.UpdateOption(hostnameOpt)
d.UpdateOption(bootFileOpt)
require.Equal(t, d.GetOneOption(OptionHostName), []byte("darkstar"))
require.Equal(t, d.GetOneOption(OptionBootfileName), []byte("boot.img"))
require.Equal(t, d.GetOneOption(OptionRouter), []byte(nil))
}
func TestUpdateOption(t *testing.T) {
d, err := New()
require.NoError(t, err)
hostnameOpt := OptGeneric(OptionHostName, []byte("darkstar"))
bootFileOpt1 := OptBootFileName("boot.img")
bootFileOpt2 := OptBootFileName("boot2.img")
d.UpdateOption(hostnameOpt)
d.UpdateOption(bootFileOpt1)
d.UpdateOption(bootFileOpt2)
options := d.Options
require.Equal(t, len(options), 2)
require.Equal(t, d.GetOneOption(OptionHostName), []byte("darkstar"))
require.Equal(t, d.GetOneOption(OptionBootfileName), []byte("boot2.img"))
}
func TestDHCPv4NewRequestFromOffer(t *testing.T) {
offer, err := New()
require.NoError(t, err)
offer.SetBroadcast()
offer.UpdateOption(OptMessageType(MessageTypeOffer))
_, err = NewRequestFromOffer(offer)
require.Error(t, err)
// Now add the option so it doesn't error out.
offer.UpdateOption(OptServerIdentifier(net.IPv4(192, 168, 0, 1)))
// Broadcast request
var req *DHCPv4
req, err = NewRequestFromOffer(offer)
require.NoError(t, err)
require.Equal(t, MessageTypeRequest, req.MessageType())
require.False(t, req.IsUnicast())
require.True(t, req.IsBroadcast())
// Following options are standard in other dhcp clients (isc-dhclient/udhcp) and required
// for final ACK to have all info for a proper lease setup (like used in u-root/pkgs/dhclient).
require.True(t, req.IsOptionRequested(OptionRouter))
require.True(t, req.IsOptionRequested(OptionSubnetMask))
require.True(t, req.IsOptionRequested(OptionDomainName))
require.True(t, req.IsOptionRequested(OptionDomainNameServer))
// Unicast request
offer.SetUnicast()
req, err = NewRequestFromOffer(offer)
require.NoError(t, err)
require.True(t, req.IsUnicast())
require.False(t, req.IsBroadcast())
}
func TestDHCPv4NewRequestFromOfferWithModifier(t *testing.T) {
offer, err := New()
require.NoError(t, err)
offer.UpdateOption(OptMessageType(MessageTypeOffer))
offer.UpdateOption(OptServerIdentifier(net.IPv4(192, 168, 0, 1)))
userClass := WithUserClass("linuxboot", false)
req, err := NewRequestFromOffer(offer, userClass)
require.NoError(t, err)
require.Equal(t, MessageTypeRequest, req.MessageType())
}
func TestNewReplyFromRequest(t *testing.T) {
discover, err := New()
require.NoError(t, err)
discover.GatewayIPAddr = net.IPv4(192, 168, 0, 1)
reply, err := NewReplyFromRequest(discover)
require.NoError(t, err)
require.Equal(t, discover.TransactionID, reply.TransactionID)
require.Equal(t, discover.GatewayIPAddr, reply.GatewayIPAddr)
}
func TestNewReplyFromRequestWithModifier(t *testing.T) {
discover, err := New()
require.NoError(t, err)
discover.GatewayIPAddr = net.IPv4(192, 168, 0, 1)
userClass := WithUserClass("linuxboot", false)
reply, err := NewReplyFromRequest(discover, userClass)
require.NoError(t, err)
require.Equal(t, discover.TransactionID, reply.TransactionID)
}
func TestDHCPv4MessageTypeNil(t *testing.T) {
m, err := New()
require.NoError(t, err)
require.Equal(t, MessageTypeNone, m.MessageType())
}
func TestNewDiscovery(t *testing.T) {
hwAddr := net.HardwareAddr{1, 2, 3, 4, 5, 6}
m, err := NewDiscovery(hwAddr)
require.NoError(t, err)
require.Equal(t, MessageTypeDiscover, m.MessageType())
// Validate fields of DISCOVER packet.
require.Equal(t, OpcodeBootRequest, m.OpCode)
require.Equal(t, iana.HWTypeEthernet, m.HWType)
require.Equal(t, hwAddr, m.ClientHWAddr)
require.True(t, m.Options.Has(OptionParameterRequestList))
}
func TestNewInform(t *testing.T) {
hwAddr := net.HardwareAddr{1, 2, 3, 4, 5, 6}
localIP := net.IPv4(10, 10, 11, 11)
m, err := NewInform(hwAddr, localIP)
require.NoError(t, err)
require.Equal(t, OpcodeBootRequest, m.OpCode)
require.Equal(t, iana.HWTypeEthernet, m.HWType)
require.Equal(t, hwAddr, m.ClientHWAddr)
require.Equal(t, MessageTypeInform, m.MessageType())
require.True(t, m.ClientIPAddr.Equal(localIP))
}
func TestIsOptionRequested(t *testing.T) {
pkt, err := New()
require.NoError(t, err)
require.False(t, pkt.IsOptionRequested(OptionDomainNameServer))
optprl := OptParameterRequestList(OptionDomainNameServer)
pkt.UpdateOption(optprl)
require.True(t, pkt.IsOptionRequested(OptionDomainNameServer))
}
// TODO
// test Summary() and String()
func TestSummary(t *testing.T) {
packet, err := New(WithMessageType(MessageTypeInform))
packet.TransactionID = [4]byte{1, 1, 1, 1}
require.NoError(t, err)
want := "DHCPv4 Message\n" +
" opcode: BootRequest\n" +
" hwtype: Ethernet\n" +
" hopcount: 0\n" +
" transaction ID: 0x01010101\n" +
" num seconds: 0\n" +
" flags: Unicast (0x00)\n" +
" client IP: 0.0.0.0\n" +
" your IP: 0.0.0.0\n" +
" server IP: 0.0.0.0\n" +
" gateway IP: 0.0.0.0\n" +
" client MAC: \n" +
" server hostname: \n" +
" bootfile name: \n" +
" options:\n" +
" DHCP Message Type: INFORM\n"
require.Equal(t, want, packet.Summary())
}
func Test_withIP(t *testing.T) {
buff := uio.NewBigEndianBuffer(make([]byte, 0, 20))
// Converting a string into IP, ip1 will be in 16 byte format
ip1 := net.ParseIP("10.0.0.1")
writeIP(buff, ip1)
b := buff.Buffer
require.Equal(t, b.Len(), 4, "Testing no of bytes written by writeIP func")
}
|
