mirror of
https://github.com/cwinfo/yggdrasil-go.git
synced 2024-11-22 10:40:27 +00:00
Remove ndp.go and add icmpv6.go
This commit is contained in:
Neil Alexander
parent
38567fffef
commit
be0d6feeba
203
src/yggdrasil/icmpv6.go
Normal file
203
src/yggdrasil/icmpv6.go
Normal file
@ -0,0 +1,203 @@
|
|||||||
|
package yggdrasil
|
||||||
|
|
||||||
|
// The NDP functions are needed when you are running with a
|
||||||
|
// TAP adapter - as the operating system expects neighbor solicitations
|
||||||
|
// for on-link traffic, this goroutine provides them
|
||||||
|
|
||||||
|
import "golang.org/x/net/icmp"
|
||||||
|
import "encoding/binary"
|
||||||
|
import "unsafe" // TODO investigate if this can be done without resorting to unsafe
|
||||||
|
|
||||||
|
type macAddress [6]byte
|
||||||
|
type ipv6Address [16]byte
|
||||||
|
|
||||||
|
const ETHER = 14
|
||||||
|
const IPV6 = 40
|
||||||
|
|
||||||
|
type icmpv6 struct {
|
||||||
|
tun *tunDevice
|
||||||
|
peermac macAddress
|
||||||
|
peerlladdr ipv6Address
|
||||||
|
mymac macAddress
|
||||||
|
mylladdr ipv6Address
|
||||||
|
recv chan []byte
|
||||||
|
}
|
||||||
|
|
||||||
|
type etherHeader struct {
|
||||||
|
destination macAddress
|
||||||
|
source macAddress
|
||||||
|
ethertype [2]byte
|
||||||
|
}
|
||||||
|
|
||||||
|
type ipv6Header struct {
|
||||||
|
preamble [4]byte
|
||||||
|
length [2]byte
|
||||||
|
nextheader byte
|
||||||
|
hoplimit byte
|
||||||
|
source ipv6Address
|
||||||
|
destination ipv6Address
|
||||||
|
}
|
||||||
|
|
||||||
|
type icmpv6Header struct {
|
||||||
|
messagetype byte
|
||||||
|
code byte
|
||||||
|
checksum uint16
|
||||||
|
}
|
||||||
|
|
||||||
|
type icmpv6PseudoHeader struct {
|
||||||
|
source ipv6Address
|
||||||
|
destination ipv6Address
|
||||||
|
length [4]byte
|
||||||
|
zero [3]byte
|
||||||
|
nextheader byte
|
||||||
|
}
|
||||||
|
|
||||||
|
type icmpv6Payload struct {
|
||||||
|
ether etherHeader
|
||||||
|
ipv6 ipv6Header
|
||||||
|
icmpv6 icmpv6Header
|
||||||
|
flags [4]byte
|
||||||
|
targetaddress ipv6Address
|
||||||
|
optiontype byte
|
||||||
|
optionlength byte
|
||||||
|
linklayeraddress macAddress
|
||||||
|
}
|
||||||
|
|
||||||
|
type icmpv6Packet struct {
|
||||||
|
ipv6 ipv6Header
|
||||||
|
payload icmpv6Payload
|
||||||
|
}
|
||||||
|
|
||||||
|
type icmpv6Frame struct {
|
||||||
|
ether etherHeader
|
||||||
|
packet icmpv6Packet
|
||||||
|
}
|
||||||
|
|
||||||
|
func (i *icmpv6) init(t *tunDevice) {
|
||||||
|
i.tun = t
|
||||||
|
i.recv = make(chan []byte)
|
||||||
|
copy(i.mymac[:], []byte{0x02, 0x00, 0x00, 0x00, 0x00, 0x02})
|
||||||
|
copy(i.mylladdr[:], []byte{
|
||||||
|
0xFE, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
|
||||||
|
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0xFE})
|
||||||
|
go i.listen()
|
||||||
|
}
|
||||||
|
|
||||||
|
func (i *icmpv6) listen() {
|
||||||
|
for {
|
||||||
|
datain := <-i.recv
|
||||||
|
|
||||||
|
if i.tun.iface.IsTAP() {
|
||||||
|
// TAP mode
|
||||||
|
dataout := make([]byte, ETHER+IPV6+32)
|
||||||
|
i.read_tap(datain, dataout)
|
||||||
|
i.tun.iface.Write(dataout)
|
||||||
|
} else {
|
||||||
|
// TUN mode
|
||||||
|
dataout := make([]byte, IPV6+32)
|
||||||
|
i.read_tun(datain, dataout)
|
||||||
|
i.tun.iface.Write(dataout)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
func (i *icmpv6) read_tap(datain []byte, dataout []byte) {
|
||||||
|
// Set up
|
||||||
|
in := (*icmpv6Frame)(unsafe.Pointer(&datain[0]))
|
||||||
|
out := (*icmpv6Frame)(unsafe.Pointer(&dataout[0]))
|
||||||
|
|
||||||
|
// Store the peer MAC address
|
||||||
|
copy(i.peermac[:6], in.ether.source[:6])
|
||||||
|
|
||||||
|
// Ignore non-IPv6 frames
|
||||||
|
if binary.BigEndian.Uint16(in.ether.ethertype[:]) != uint16(0x86DD) {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
|
||||||
|
// Populate the out ethernet headers
|
||||||
|
copy(out.ether.destination[:], in.ether.destination[:])
|
||||||
|
copy(out.ether.source[:], i.mymac[:])
|
||||||
|
binary.BigEndian.PutUint16(out.ether.ethertype[:], uint16(0x86DD))
|
||||||
|
|
||||||
|
// And for now just copy the rest of the packet we were sent
|
||||||
|
copy(dataout[ETHER:ETHER+IPV6], datain[ETHER:ETHER+IPV6])
|
||||||
|
|
||||||
|
// Then pass the IP packet onto the next function
|
||||||
|
i.read_tun(datain[ETHER:], dataout[ETHER:])
|
||||||
|
}
|
||||||
|
|
||||||
|
func (i *icmpv6) read_tun(datain []byte, dataout []byte) {
|
||||||
|
// Set up
|
||||||
|
in := (*icmpv6Packet)(unsafe.Pointer(&datain[0]))
|
||||||
|
out := (*icmpv6Packet)(unsafe.Pointer(&dataout[0]))
|
||||||
|
|
||||||
|
// Store the peer link-local address
|
||||||
|
copy(i.peerlladdr[:16], in.ipv6.source[:16])
|
||||||
|
|
||||||
|
// Ignore non-ICMPv6 packets
|
||||||
|
if in.ipv6.nextheader != uint8(0x3A) {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
|
||||||
|
// What is the ICMPv6 message type?
|
||||||
|
switch in.payload.icmpv6.messagetype {
|
||||||
|
case uint8(135):
|
||||||
|
i.handle_ndp(&in.payload, &out.payload)
|
||||||
|
break
|
||||||
|
}
|
||||||
|
|
||||||
|
// Update the source and destination addresses in the IPv6 header
|
||||||
|
copy(out.ipv6.destination[:], in.ipv6.source[:])
|
||||||
|
copy(out.ipv6.source[:], i.mylladdr[:])
|
||||||
|
binary.BigEndian.PutUint16(out.ipv6.length[:], uint16(32))
|
||||||
|
|
||||||
|
// Copy the payload
|
||||||
|
copy(dataout[IPV6:], datain[IPV6:])
|
||||||
|
|
||||||
|
// Calculate the checksum
|
||||||
|
i.calculate_checksum(dataout)
|
||||||
|
}
|
||||||
|
|
||||||
|
func (i *icmpv6) calculate_checksum(dataout []byte) {
|
||||||
|
// Set up
|
||||||
|
out := (*icmpv6Packet)(unsafe.Pointer(&dataout[0]))
|
||||||
|
|
||||||
|
// Generate the pseudo-header for the checksum
|
||||||
|
ps := make([]byte, 44)
|
||||||
|
pseudo := (*icmpv6PseudoHeader)(unsafe.Pointer(&ps[0]))
|
||||||
|
copy(pseudo.destination[:], out.ipv6.destination[:])
|
||||||
|
copy(pseudo.source[:], out.ipv6.source[:])
|
||||||
|
binary.BigEndian.PutUint32(pseudo.length[:], uint32(binary.BigEndian.Uint16(out.ipv6.length[:])))
|
||||||
|
pseudo.nextheader = out.ipv6.nextheader
|
||||||
|
|
||||||
|
// Lazy-man's checksum using the icmp library
|
||||||
|
icmpv6, err := icmp.ParseMessage(0x3A, dataout[IPV6:])
|
||||||
|
if err != nil {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
|
||||||
|
// And copy the payload
|
||||||
|
payload, err := icmpv6.Marshal(ps)
|
||||||
|
if err != nil {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
copy(dataout[IPV6:], payload)
|
||||||
|
}
|
||||||
|
|
||||||
|
func (i *icmpv6) handle_ndp(in *icmpv6Payload, out *icmpv6Payload) {
|
||||||
|
// Ignore NDP requests for anything outside of fd00::/8
|
||||||
|
if in.targetaddress[0] != 0xFD {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
|
||||||
|
// Update the ICMPv6 headers
|
||||||
|
out.icmpv6.messagetype = uint8(136)
|
||||||
|
out.icmpv6.code = uint8(0)
|
||||||
|
|
||||||
|
// Update the ICMPv6 payload
|
||||||
|
copy(out.targetaddress[:], in.targetaddress[:])
|
||||||
|
out.optiontype = uint8(2)
|
||||||
|
out.optionlength = uint8(1)
|
||||||
|
copy(out.linklayeraddress[:], i.mymac[:])
|
||||||
|
binary.BigEndian.PutUint32(out.flags[:], uint32(0x20000000))
|
||||||
|
}
|
||||||
@ -1,165 +0,0 @@
|
|||||||
package yggdrasil
|
|
||||||
|
|
||||||
// The NDP functions are needed when you are running with a
|
|
||||||
// TAP adapter - as the operating system expects neighbor solicitations
|
|
||||||
// for on-link traffic, this goroutine provides them
|
|
||||||
|
|
||||||
import "golang.org/x/net/icmp"
|
|
||||||
import "encoding/binary"
|
|
||||||
import "unsafe" // TODO investigate if this can be done without resorting to unsafe
|
|
||||||
|
|
||||||
type macAddress [6]byte
|
|
||||||
type ipv6Address [16]byte
|
|
||||||
|
|
||||||
const ETHER = 14
|
|
||||||
const IPV6 = 40
|
|
||||||
|
|
||||||
type ndp struct {
|
|
||||||
tun *tunDevice
|
|
||||||
peermac macAddress
|
|
||||||
peerlladdr ipv6Address
|
|
||||||
mymac macAddress
|
|
||||||
mylladdr ipv6Address
|
|
||||||
recv chan []byte
|
|
||||||
}
|
|
||||||
|
|
||||||
type etherHeader struct {
|
|
||||||
destination macAddress
|
|
||||||
source macAddress
|
|
||||||
ethertype [2]byte
|
|
||||||
}
|
|
||||||
|
|
||||||
type ipv6Header struct {
|
|
||||||
preamble [4]byte
|
|
||||||
length [2]byte
|
|
||||||
nextheader byte
|
|
||||||
hoplimit byte
|
|
||||||
source ipv6Address
|
|
||||||
destination ipv6Address
|
|
||||||
}
|
|
||||||
|
|
||||||
type icmpv6Header struct {
|
|
||||||
messagetype byte
|
|
||||||
code byte
|
|
||||||
checksum uint16
|
|
||||||
}
|
|
||||||
|
|
||||||
type icmpv6PseudoHeader struct {
|
|
||||||
source ipv6Address
|
|
||||||
destination ipv6Address
|
|
||||||
length [4]byte
|
|
||||||
zero [3]byte
|
|
||||||
nextheader byte
|
|
||||||
}
|
|
||||||
|
|
||||||
type icmpv6Packet struct {
|
|
||||||
ether etherHeader
|
|
||||||
ipv6 ipv6Header
|
|
||||||
icmpv6 icmpv6Header
|
|
||||||
flags [4]byte
|
|
||||||
targetaddress ipv6Address
|
|
||||||
optiontype byte
|
|
||||||
optionlength byte
|
|
||||||
linklayeraddress macAddress
|
|
||||||
}
|
|
||||||
|
|
||||||
func (n *ndp) init(t *tunDevice) {
|
|
||||||
n.tun = t
|
|
||||||
n.recv = make(chan []byte)
|
|
||||||
copy(n.mymac[:], []byte{0x02, 0x00, 0x00, 0x00, 0x00, 0x02})
|
|
||||||
copy(n.mylladdr[:], []byte{
|
|
||||||
0xFE, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
|
|
||||||
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0xFE})
|
|
||||||
go n.listen()
|
|
||||||
}
|
|
||||||
|
|
||||||
func (n *ndp) listen() {
|
|
||||||
for {
|
|
||||||
// Receive from the channel and check if we're using TAP instead
|
|
||||||
// of TUN mode - NDP is only relevant for TAP
|
|
||||||
datain := <-n.recv
|
|
||||||
if !n.tun.iface.IsTAP() {
|
|
||||||
continue
|
|
||||||
}
|
|
||||||
|
|
||||||
// Create our return frame buffer and also the unsafe pointers to
|
|
||||||
// map them to the structs
|
|
||||||
dataout := make([]byte, ETHER+IPV6+32)
|
|
||||||
in := (*icmpv6Packet)(unsafe.Pointer(&datain[0]))
|
|
||||||
out := (*icmpv6Packet)(unsafe.Pointer(&dataout[0]))
|
|
||||||
|
|
||||||
// Store peer MAC address and link-local IP address -
|
|
||||||
// these will be used later by tun.go
|
|
||||||
copy(n.peermac[:6], in.ether.source[:6])
|
|
||||||
copy(n.peerlladdr[:16], in.ipv6.source[:16])
|
|
||||||
|
|
||||||
// Ignore non-IPv6 packets
|
|
||||||
if binary.BigEndian.Uint16(in.ether.ethertype[:]) != uint16(0x86DD) {
|
|
||||||
continue
|
|
||||||
}
|
|
||||||
|
|
||||||
// Ignore non-ICMPv6 packets
|
|
||||||
if in.ipv6.nextheader != uint8(0x3A) {
|
|
||||||
continue
|
|
||||||
}
|
|
||||||
|
|
||||||
// Ignore non-NDP Solicitation packets
|
|
||||||
if in.icmpv6.messagetype != uint8(135) {
|
|
||||||
continue
|
|
||||||
}
|
|
||||||
|
|
||||||
// Ignore NDP requests for anything outside of fd00::/8
|
|
||||||
if in.targetaddress[0] != 0xFD {
|
|
||||||
continue
|
|
||||||
}
|
|
||||||
|
|
||||||
// Populate the out ethernet headers
|
|
||||||
copy(out.ether.destination[:], in.ether.destination[:])
|
|
||||||
copy(out.ether.source[:], n.mymac[:])
|
|
||||||
binary.BigEndian.PutUint16(out.ether.ethertype[:], uint16(0x86DD))
|
|
||||||
|
|
||||||
// And for now just copy the rest of the packet we were sent
|
|
||||||
copy(dataout[ETHER:ETHER+IPV6], datain[ETHER:ETHER+IPV6])
|
|
||||||
|
|
||||||
// Update the source and destination addresses in the IPv6 header
|
|
||||||
copy(out.ipv6.destination[:], in.ipv6.source[:])
|
|
||||||
copy(out.ipv6.source[:], n.mylladdr[:])
|
|
||||||
binary.BigEndian.PutUint16(out.ipv6.length[:], uint16(32))
|
|
||||||
|
|
||||||
// Copy the payload
|
|
||||||
copy(dataout[ETHER+IPV6:], datain[ETHER+IPV6:])
|
|
||||||
|
|
||||||
// Update the ICMPv6 headers
|
|
||||||
out.icmpv6.messagetype = uint8(136)
|
|
||||||
out.icmpv6.code = uint8(0)
|
|
||||||
|
|
||||||
// Update the ICMPv6 payload
|
|
||||||
copy(out.targetaddress[:], in.targetaddress[:])
|
|
||||||
out.optiontype = uint8(2)
|
|
||||||
out.optionlength = uint8(1)
|
|
||||||
copy(out.linklayeraddress[:], n.mymac[:])
|
|
||||||
binary.BigEndian.PutUint32(out.flags[:], uint32(0x20000000))
|
|
||||||
|
|
||||||
// Generate the pseudo-header for the checksum
|
|
||||||
ps := make([]byte, 44)
|
|
||||||
pseudo := (*icmpv6PseudoHeader)(unsafe.Pointer(&ps[0]))
|
|
||||||
copy(pseudo.destination[:], out.ipv6.destination[:])
|
|
||||||
copy(pseudo.source[:], out.ipv6.source[:])
|
|
||||||
binary.BigEndian.PutUint32(pseudo.length[:], uint32(binary.BigEndian.Uint16(out.ipv6.length[:])))
|
|
||||||
pseudo.nextheader = out.ipv6.nextheader
|
|
||||||
|
|
||||||
// Lazy-man's checksum using the icmp library
|
|
||||||
icmpv6, err := icmp.ParseMessage(0x3A, dataout[ETHER+IPV6:])
|
|
||||||
if err != nil {
|
|
||||||
continue
|
|
||||||
}
|
|
||||||
payload, err := icmpv6.Marshal(ps)
|
|
||||||
if err != nil {
|
|
||||||
continue
|
|
||||||
}
|
|
||||||
copy(dataout[ETHER+IPV6:], payload)
|
|
||||||
|
|
||||||
// Send the frame back to the TAP adapter
|
|
||||||
n.tun.iface.Write(dataout)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
@ -17,17 +17,17 @@ type tunInterface interface {
|
|||||||
}
|
}
|
||||||
|
|
||||||
type tunDevice struct {
|
type tunDevice struct {
|
||||||
core *Core
|
core *Core
|
||||||
ndp ndp
|
icmpv6 icmpv6
|
||||||
send chan<- []byte
|
send chan<- []byte
|
||||||
recv <-chan []byte
|
recv <-chan []byte
|
||||||
mtu int
|
mtu int
|
||||||
iface tunInterface
|
iface tunInterface
|
||||||
}
|
}
|
||||||
|
|
||||||
func (tun *tunDevice) init(core *Core) {
|
func (tun *tunDevice) init(core *Core) {
|
||||||
tun.core = core
|
tun.core = core
|
||||||
tun.ndp.init(tun)
|
tun.icmpv6.init(tun)
|
||||||
}
|
}
|
||||||
|
|
||||||
func (tun *tunDevice) write() error {
|
func (tun *tunDevice) write() error {
|
||||||
@ -36,11 +36,11 @@ func (tun *tunDevice) write() error {
|
|||||||
if tun.iface.IsTAP() {
|
if tun.iface.IsTAP() {
|
||||||
var frame ethernet.Frame
|
var frame ethernet.Frame
|
||||||
frame.Prepare(
|
frame.Prepare(
|
||||||
tun.ndp.peermac[:6], // Destination MAC address
|
tun.icmpv6.peermac[:6], // Destination MAC address
|
||||||
tun.ndp.mymac[:6], // Source MAC address
|
tun.icmpv6.mymac[:6], // Source MAC address
|
||||||
ethernet.NotTagged, // VLAN tagging
|
ethernet.NotTagged, // VLAN tagging
|
||||||
ethernet.IPv6, // Ethertype
|
ethernet.IPv6, // Ethertype
|
||||||
len(data)) // Payload length
|
len(data)) // Payload length
|
||||||
copy(frame[ETHER_HEADER_LENGTH:], data[:])
|
copy(frame[ETHER_HEADER_LENGTH:], data[:])
|
||||||
if _, err := tun.iface.Write(frame); err != nil {
|
if _, err := tun.iface.Write(frame); err != nil {
|
||||||
panic(err)
|
panic(err)
|
||||||
@ -68,9 +68,6 @@ func (tun *tunDevice) read() error {
|
|||||||
o := 0
|
o := 0
|
||||||
if tun.iface.IsTAP() {
|
if tun.iface.IsTAP() {
|
||||||
o = ETHER_HEADER_LENGTH
|
o = ETHER_HEADER_LENGTH
|
||||||
b := make([]byte, n)
|
|
||||||
copy(b, buf)
|
|
||||||
tun.ndp.recv <- b
|
|
||||||
}
|
}
|
||||||
if buf[o]&0xf0 != 0x60 ||
|
if buf[o]&0xf0 != 0x60 ||
|
||||||
n != 256*int(buf[o+4])+int(buf[o+5])+IPv6_HEADER_LENGTH+o {
|
n != 256*int(buf[o+4])+int(buf[o+5])+IPv6_HEADER_LENGTH+o {
|
||||||
@ -78,6 +75,12 @@ func (tun *tunDevice) read() error {
|
|||||||
//panic("Should not happen in testing")
|
//panic("Should not happen in testing")
|
||||||
continue
|
continue
|
||||||
}
|
}
|
||||||
|
if buf[o+6] == 58 {
|
||||||
|
// Found an ICMPv6 packet
|
||||||
|
b := make([]byte, n)
|
||||||
|
copy(b, buf)
|
||||||
|
tun.icmpv6.recv <- b
|
||||||
|
}
|
||||||
packet := append(util_getBytes(), buf[o:n]...)
|
packet := append(util_getBytes(), buf[o:n]...)
|
||||||
tun.send <- packet
|
tun.send <- packet
|
||||||
}
|
}
|
||||||
|
|||||||
Loading…
Reference in New Issue
Block a user