Added new UDPBind interface

This commit is contained in:
Mathias Hall-Andersen 2017-10-08 22:03:32 +02:00
parent 2d856045a0
commit a72b0f7ae5
6 changed files with 236 additions and 214 deletions

View file

@ -5,6 +5,14 @@ import (
"net"
)
type UDPBind interface {
SetMark(value uint32) error
ReceiveIPv6(buff []byte, end *Endpoint) (int, error)
ReceiveIPv4(buff []byte, end *Endpoint) (int, error)
Send(buff []byte, end *Endpoint) error
Close() error
}
func parseEndpoint(s string) (*net.UDPAddr, error) {
// ensure that the host is an IP address
@ -26,19 +34,6 @@ func parseEndpoint(s string) (*net.UDPAddr, error) {
return addr, err
}
func ListenerClose(l *Listener) (err error) {
if l.active {
err = CloseIPv4Socket(l.sock)
l.active = false
}
return
}
func (l *Listener) Init() {
l.update = make(chan struct{}, 1)
ListenerClose(l)
}
func ListeningUpdate(device *Device) error {
netc := &device.net
netc.mutex.Lock()
@ -46,11 +41,7 @@ func ListeningUpdate(device *Device) error {
// close existing sockets
if err := ListenerClose(&netc.ipv4); err != nil {
return err
}
if err := ListenerClose(&netc.ipv6); err != nil {
if err := device.net.bind.Close(); err != nil {
return err
}
@ -58,45 +49,22 @@ func ListeningUpdate(device *Device) error {
if device.tun.isUp.Get() {
// listen on IPv4
// bind to new port
{
list := &netc.ipv6
sock, port, err := CreateIPv4Socket(netc.port)
if err != nil {
return err
}
netc.port = port
list.sock = sock
list.active = true
if err := SetMark(list.sock, netc.fwmark); err != nil {
ListenerClose(list)
return err
}
signalSend(list.update)
var err error
netc.bind, netc.port, err = CreateUDPBind(netc.port)
if err != nil {
return err
}
// listen on IPv6
// set mark
{
list := &netc.ipv6
sock, port, err := CreateIPv6Socket(netc.port)
if err != nil {
return err
}
netc.port = port
list.sock = sock
list.active = true
if err := SetMark(list.sock, netc.fwmark); err != nil {
ListenerClose(list)
return err
}
signalSend(list.update)
err = netc.bind.SetMark(netc.fwmark)
if err != nil {
return err
}
// TODO: clear endpoint caches
// TODO: clear endpoint (src) caches
}
return nil
@ -106,16 +74,5 @@ func ListeningClose(device *Device) error {
netc := &device.net
netc.mutex.Lock()
defer netc.mutex.Unlock()
if err := ListenerClose(&netc.ipv4); err != nil {
return err
}
signalSend(netc.ipv4.update)
if err := ListenerClose(&netc.ipv6); err != nil {
return err
}
signalSend(netc.ipv6.update)
return nil
return netc.bind.Close()
}

View file

@ -14,35 +14,158 @@ import (
"unsafe"
)
import "fmt"
/* Supports source address caching
*
* Currently there is no way to achieve this within the net package:
* See e.g. https://github.com/golang/go/issues/17930
* So this code is platform dependent.
*
* It is important that the endpoint is only updated after the packet content has been authenticated!
* So this code is remains platform dependent.
*/
type Endpoint struct {
// source (selected based on dst type)
// (could use RawSockaddrAny and unsafe)
// TODO: Merge
src6 unix.RawSockaddrInet6
src4 unix.RawSockaddrInet4
src4if int32
dst unix.RawSockaddrAny
src unix.RawSockaddrInet6
dst unix.RawSockaddrInet6
}
type Socket int
type IPv4Source struct {
src unix.RawSockaddrInet4
Ifindex int32
}
/* Returns a byte representation of the source field(s)
* for use in "under load" cookie computations.
*/
func (endpoint *Endpoint) Source() []byte {
return nil
type Bind struct {
sock4 int
sock6 int
}
func CreateUDPBind(port uint16) (UDPBind, uint16, error) {
var err error
var bind Bind
bind.sock6, port, err = create6(port)
if err != nil {
return nil, port, err
}
bind.sock4, port, err = create4(port)
if err != nil {
unix.Close(bind.sock6)
}
return &bind, port, err
}
func (bind *Bind) SetMark(value uint32) error {
err := unix.SetsockoptInt(
bind.sock6,
unix.SOL_SOCKET,
unix.SO_MARK,
int(value),
)
if err != nil {
return err
}
return unix.SetsockoptInt(
bind.sock4,
unix.SOL_SOCKET,
unix.SO_MARK,
int(value),
)
}
func (bind *Bind) Close() error {
err1 := unix.Close(bind.sock6)
err2 := unix.Close(bind.sock4)
if err1 != nil {
return err1
}
return err2
}
func (bind *Bind) ReceiveIPv6(buff []byte, end *Endpoint) (int, error) {
return receive6(
bind.sock6,
buff,
end,
)
}
func (bind *Bind) ReceiveIPv4(buff []byte, end *Endpoint) (int, error) {
return receive4(
bind.sock4,
buff,
end,
)
}
func (bind *Bind) Send(buff []byte, end *Endpoint) error {
switch end.src.Family {
case unix.AF_INET6:
return send6(bind.sock6, end, buff)
case unix.AF_INET:
return send4(bind.sock4, end, buff)
default:
return errors.New("Unknown address family of source")
}
}
func sockaddrToString(addr unix.RawSockaddrInet6) string {
var udpAddr net.UDPAddr
switch addr.Family {
case unix.AF_INET6:
udpAddr.Port = int(addr.Port)
udpAddr.IP = addr.Addr[:]
return udpAddr.String()
case unix.AF_INET:
ptr := (*unix.RawSockaddrInet4)(unsafe.Pointer(&addr))
udpAddr.Port = int(ptr.Port)
udpAddr.IP = net.IPv4(
ptr.Addr[0],
ptr.Addr[1],
ptr.Addr[2],
ptr.Addr[3],
)
return udpAddr.String()
default:
return "<unknown address family>"
}
}
func (end *Endpoint) DestinationIP() net.IP {
switch end.dst.Family {
case unix.AF_INET6:
return end.dst.Addr[:]
case unix.AF_INET:
ptr := (*unix.RawSockaddrInet4)(unsafe.Pointer(&end.dst))
return net.IPv4(
ptr.Addr[0],
ptr.Addr[1],
ptr.Addr[2],
ptr.Addr[3],
)
default:
return nil
}
}
func (end *Endpoint) SourceToBytes() []byte {
ptr := unsafe.Pointer(&end.src)
arr := (*[unix.SizeofSockaddrInet6]byte)(ptr)
return arr[:]
}
func (end *Endpoint) SourceToString() string {
return sockaddrToString(end.src)
}
func (end *Endpoint) DestinationToString() string {
return sockaddrToString(end.dst)
}
func (end *Endpoint) ClearSrc() {
end.src = unix.RawSockaddrInet6{}
}
func zoneToUint32(zone string) (uint32, error) {
@ -56,7 +179,7 @@ func zoneToUint32(zone string) (uint32, error) {
return uint32(n), err
}
func CreateIPv4Socket(port uint16) (Socket, uint16, error) {
func create4(port uint16) (int, uint16, error) {
// create socket
@ -100,18 +223,10 @@ func CreateIPv4Socket(port uint16) (Socket, uint16, error) {
unix.Close(fd)
}
return Socket(fd), uint16(addr.Port), err
return fd, uint16(addr.Port), err
}
func CloseIPv4Socket(sock Socket) error {
return unix.Close(int(sock))
}
func CloseIPv6Socket(sock Socket) error {
return unix.Close(int(sock))
}
func CreateIPv6Socket(port uint16) (Socket, uint16, error) {
func create6(port uint16) (int, uint16, error) {
// create socket
@ -166,13 +281,7 @@ func CreateIPv6Socket(port uint16) (Socket, uint16, error) {
unix.Close(fd)
}
return Socket(fd), uint16(addr.Port), err
}
func (end *Endpoint) ClearSrc() {
end.src4if = 0
end.src4 = unix.RawSockaddrInet4{}
end.src6 = unix.RawSockaddrInet6{}
return fd, uint16(addr.Port), err
}
func (end *Endpoint) Set(s string) error {
@ -187,23 +296,23 @@ func (end *Endpoint) Set(s string) error {
if err != nil {
return err
}
ptr := (*unix.RawSockaddrInet6)(unsafe.Pointer(&end.dst))
ptr.Family = unix.AF_INET6
ptr.Port = uint16(addr.Port)
ptr.Flowinfo = 0
ptr.Scope_id = zone
copy(ptr.Addr[:], ipv6[:])
dst := &end.dst
dst.Family = unix.AF_INET6
dst.Port = uint16(addr.Port)
dst.Flowinfo = 0
dst.Scope_id = zone
copy(dst.Addr[:], ipv6[:])
end.ClearSrc()
return nil
}
ipv4 := addr.IP.To4()
if ipv4 != nil {
ptr := (*unix.RawSockaddrInet4)(unsafe.Pointer(&end.dst))
ptr.Family = unix.AF_INET
ptr.Port = uint16(addr.Port)
ptr.Zero = [8]byte{}
copy(ptr.Addr[:], ipv4)
dst := (*unix.RawSockaddrInet4)(unsafe.Pointer(&end.dst))
dst.Family = unix.AF_INET
dst.Port = uint16(addr.Port)
dst.Zero = [8]byte{}
copy(dst.Addr[:], ipv4)
end.ClearSrc()
return nil
}
@ -211,7 +320,7 @@ func (end *Endpoint) Set(s string) error {
return errors.New("Failed to recognize IP address format")
}
func send6(sock uintptr, end *Endpoint, buff []byte) error {
func send6(sock int, end *Endpoint, buff []byte) error {
// construct message header
@ -229,8 +338,8 @@ func send6(sock uintptr, end *Endpoint, buff []byte) error {
Len: unix.SizeofInet6Pktinfo,
},
unix.Inet6Pktinfo{
Addr: end.src6.Addr,
Ifindex: end.src6.Scope_id,
Addr: end.src.Addr,
Ifindex: end.src.Scope_id,
},
}
@ -248,7 +357,7 @@ func send6(sock uintptr, end *Endpoint, buff []byte) error {
_, _, errno := unix.Syscall(
unix.SYS_SENDMSG,
sock,
uintptr(sock),
uintptr(unsafe.Pointer(&msghdr)),
0,
)
@ -258,7 +367,7 @@ func send6(sock uintptr, end *Endpoint, buff []byte) error {
return errno
}
func send4(sock uintptr, end *Endpoint, buff []byte) error {
func send4(sock int, end *Endpoint, buff []byte) error {
// construct message header
@ -266,6 +375,8 @@ func send4(sock uintptr, end *Endpoint, buff []byte) error {
iovec.Base = (*byte)(unsafe.Pointer(&buff[0]))
iovec.SetLen(len(buff))
src4 := (*IPv4Source)(unsafe.Pointer(&end.src))
cmsg := struct {
cmsghdr unix.Cmsghdr
pktinfo unix.Inet4Pktinfo
@ -276,8 +387,8 @@ func send4(sock uintptr, end *Endpoint, buff []byte) error {
Len: unix.SizeofInet4Pktinfo,
},
unix.Inet4Pktinfo{
Spec_dst: end.src4.Addr,
Ifindex: end.src4if,
Spec_dst: src4.src.Addr,
Ifindex: src4.Ifindex,
},
}
@ -295,7 +406,7 @@ func send4(sock uintptr, end *Endpoint, buff []byte) error {
_, _, errno := unix.Syscall(
unix.SYS_SENDMSG,
sock,
uintptr(sock),
uintptr(unsafe.Pointer(&msghdr)),
0,
)
@ -305,28 +416,7 @@ func send4(sock uintptr, end *Endpoint, buff []byte) error {
return errno
}
func (end *Endpoint) Send(c *net.UDPConn, buff []byte) error {
// extract underlying file descriptor
file, err := c.File()
if err != nil {
return err
}
sock := file.Fd()
// send depending on address family of dst
family := *((*uint16)(unsafe.Pointer(&end.dst)))
if family == unix.AF_INET {
return send4(sock, end, buff)
} else if family == unix.AF_INET6 {
return send6(sock, end, buff)
}
return errors.New("Unknown address family of source")
}
func (end *Endpoint) ReceiveIPv4(sock Socket, buff []byte) (int, error) {
func receive4(sock int, buff []byte, end *Endpoint) (int, error) {
// contruct message header
@ -360,22 +450,21 @@ func (end *Endpoint) ReceiveIPv4(sock Socket, buff []byte) (int, error) {
return 0, errno
}
fmt.Println(msghdr)
fmt.Println(cmsg)
// update source cache
if cmsg.cmsghdr.Level == unix.IPPROTO_IP &&
cmsg.cmsghdr.Type == unix.IP_PKTINFO &&
cmsg.cmsghdr.Len >= unix.SizeofInet4Pktinfo {
end.src4.Addr = cmsg.pktinfo.Spec_dst
end.src4if = cmsg.pktinfo.Ifindex
src4 := (*IPv4Source)(unsafe.Pointer(&end.src))
src4.src.Family = unix.AF_INET
src4.src.Addr = cmsg.pktinfo.Spec_dst
src4.Ifindex = cmsg.pktinfo.Ifindex
}
return int(size), nil
}
func (end *Endpoint) ReceiveIPv6(sock Socket, buff []byte) (int, error) {
func receive6(sock int, buff []byte, end *Endpoint) (int, error) {
// contruct message header
@ -414,18 +503,10 @@ func (end *Endpoint) ReceiveIPv6(sock Socket, buff []byte) (int, error) {
if cmsg.cmsghdr.Level == unix.IPPROTO_IPV6 &&
cmsg.cmsghdr.Type == unix.IPV6_PKTINFO &&
cmsg.cmsghdr.Len >= unix.SizeofInet6Pktinfo {
end.src6.Addr = cmsg.pktinfo.Addr
end.src6.Scope_id = cmsg.pktinfo.Ifindex
end.src.Family = unix.AF_INET6
end.src.Addr = cmsg.pktinfo.Addr
end.src.Scope_id = cmsg.pktinfo.Ifindex
}
return int(size), nil
}
func SetMark(sock Socket, value uint32) error {
return unix.SetsockoptInt(
int(sock),
unix.SOL_SOCKET,
unix.SO_MARK,
int(value),
)
}

View file

@ -5,10 +5,8 @@ import (
"crypto/rand"
"golang.org/x/crypto/blake2s"
"golang.org/x/crypto/chacha20poly1305"
"net"
"sync"
"time"
"unsafe"
)
type CookieChecker struct {
@ -76,7 +74,7 @@ func (st *CookieChecker) CheckMAC1(msg []byte) bool {
return hmac.Equal(mac1[:], msg[smac1:smac2])
}
func (st *CookieChecker) CheckMAC2(msg []byte, src *net.UDPAddr) bool {
func (st *CookieChecker) CheckMAC2(msg []byte, src []byte) bool {
st.mutex.RLock()
defer st.mutex.RUnlock()
@ -89,8 +87,7 @@ func (st *CookieChecker) CheckMAC2(msg []byte, src *net.UDPAddr) bool {
var cookie [blake2s.Size128]byte
func() {
mac, _ := blake2s.New128(st.mac2.secret[:])
mac.Write(src.IP)
mac.Write((*[unsafe.Sizeof(src.Port)]byte)(unsafe.Pointer(&src.Port))[:])
mac.Write(src)
mac.Sum(cookie[:0])
}()
@ -111,7 +108,7 @@ func (st *CookieChecker) CheckMAC2(msg []byte, src *net.UDPAddr) bool {
func (st *CookieChecker) CreateReply(
msg []byte,
recv uint32,
src *net.UDPAddr,
src []byte,
) (*MessageCookieReply, error) {
st.mutex.RLock()
@ -136,8 +133,7 @@ func (st *CookieChecker) CreateReply(
var cookie [blake2s.Size128]byte
func() {
mac, _ := blake2s.New128(st.mac2.secret[:])
mac.Write(src.IP)
mac.Write((*[unsafe.Sizeof(src.Port)]byte)(unsafe.Pointer(&src.Port))[:])
mac.Write(src)
mac.Sum(cookie[:0])
}()

View file

@ -1,18 +1,14 @@
package main
import (
"golang.org/x/net/ipv4"
"golang.org/x/net/ipv6"
"runtime"
"sync"
"sync/atomic"
"time"
)
type Listener struct {
sock Socket
active bool
update chan struct{}
}
type Device struct {
log *Logger // collection of loggers for levels
idCounter uint // for assigning debug ids to peers
@ -27,8 +23,7 @@ type Device struct {
}
net struct {
mutex sync.RWMutex
ipv4 Listener
ipv6 Listener
bind UDPBind
port uint16
fwmark uint32
}
@ -43,9 +38,8 @@ type Device struct {
handshake chan QueueHandshakeElement
}
signal struct {
stop chan struct{} // halts all go routines
updateIPv4Socket chan struct{} // a net.conn was set (consumed by the receiver routine)
updateIPv6Socket chan struct{} // a net.conn was set (consumed by the receiver routine)
stop chan struct{}
updateBind chan struct{}
}
underLoadUntil atomic.Value
ratelimiter Ratelimiter
@ -146,8 +140,6 @@ func NewDevice(tun TUNDevice, logLevel int) *Device {
device.tun.device = tun
device.indices.Init()
device.net.ipv4.Init()
device.net.ipv6.Init()
device.ratelimiter.Init()
device.routingTable.Reset()
@ -181,8 +173,8 @@ func NewDevice(tun TUNDevice, logLevel int) *Device {
go device.RoutineReadFromTUN()
go device.RoutineTUNEventReader()
go device.ratelimiter.RoutineGarbageCollector(device.signal.stop)
go device.RoutineReceiveIncomming(&device.net.ipv4)
go device.RoutineReceiveIncomming(&device.net.ipv6)
go device.RoutineReceiveIncomming(ipv4.Version)
go device.RoutineReceiveIncomming(ipv6.Version)
return device
}

View file

@ -4,7 +4,6 @@ import (
"encoding/base64"
"errors"
"fmt"
"net"
"sync"
"time"
)
@ -15,8 +14,8 @@ type Peer struct {
persistentKeepaliveInterval uint64
keyPairs KeyPairs
handshake Handshake
endpoint Endpoint
device *Device
endpoint *net.UDPAddr
stats struct {
txBytes uint64 // bytes send to peer (endpoint)
rxBytes uint64 // bytes received from peer
@ -134,7 +133,7 @@ func (peer *Peer) String() string {
return fmt.Sprintf(
"peer(%d %s %s)",
peer.id,
peer.endpoint.String(),
peer.endpoint.DestinationToString(),
base64.StdEncoding.EncodeToString(peer.handshake.remoteStatic[:]),
)
}

View file

@ -97,17 +97,6 @@ func (device *Device) RoutineReceiveIncomming(IPVersion int) {
logDebug := device.log.Debug
logDebug.Println("Routine, receive incomming, started")
var listener *Listener
switch IPVersion {
case ipv4.Version:
listener = &device.net.ipv4
case ipv6.Version:
listener = &device.net.ipv6
default:
return
}
for {
// wait for new conn
@ -118,15 +107,14 @@ func (device *Device) RoutineReceiveIncomming(IPVersion int) {
case <-device.signal.stop:
return
case <-listener.update:
case <-device.signal.updateBind:
// fetch new socket
device.net.mutex.RLock()
sock := listener.sock
okay := listener.active
bind := device.net.bind
device.net.mutex.RUnlock()
if !okay {
if bind == nil {
continue
}
@ -145,10 +133,13 @@ func (device *Device) RoutineReceiveIncomming(IPVersion int) {
var endpoint Endpoint
if IPVersion == ipv6.Version {
size, err = endpoint.ReceiveIPv4(sock, buffer[:])
} else {
size, err = endpoint.ReceiveIPv6(sock, buffer[:])
switch IPVersion {
case ipv4.Version:
size, err = bind.ReceiveIPv4(buffer[:], &endpoint)
case ipv6.Version:
size, err = bind.ReceiveIPv6(buffer[:], &endpoint)
default:
return
}
if err != nil {
@ -340,15 +331,19 @@ func (device *Device) RoutineHandshake() {
return
}
srcBytes := elem.endpoint.SourceToBytes()
if device.IsUnderLoad() {
if !device.mac.CheckMAC2(elem.packet, elem.source) {
// verify MAC2 field
if !device.mac.CheckMAC2(elem.packet, srcBytes) {
// construct cookie reply
logDebug.Println("Sending cookie reply to:", elem.source.String())
logDebug.Println("Sending cookie reply to:", elem.endpoint.SourceToString())
sender := binary.LittleEndian.Uint32(elem.packet[4:8]) // "sender" always follows "type"
reply, err := device.mac.CreateReply(elem.packet, sender, elem.source)
reply, err := device.mac.CreateReply(elem.packet, sender, srcBytes)
if err != nil {
logError.Println("Failed to create cookie reply:", err)
return
@ -358,9 +353,9 @@ func (device *Device) RoutineHandshake() {
writer := bytes.NewBuffer(temp[:0])
binary.Write(writer, binary.LittleEndian, reply)
_, err = device.net.conn.WriteToUDP(
device.net.bind.Send(
writer.Bytes(),
elem.source,
&elem.endpoint,
)
if err != nil {
logDebug.Println("Failed to send cookie reply:", err)
@ -368,7 +363,11 @@ func (device *Device) RoutineHandshake() {
continue
}
if !device.ratelimiter.Allow(elem.source.IP) {
// check ratelimiter
if !device.ratelimiter.Allow(
elem.endpoint.DestinationIP(),
) {
continue
}
}
@ -399,8 +398,7 @@ func (device *Device) RoutineHandshake() {
if peer == nil {
logInfo.Println(
"Recieved invalid initiation message from",
elem.source.IP.String(),
elem.source.Port,
elem.endpoint.DestinationToString(),
)
continue
}
@ -414,7 +412,7 @@ func (device *Device) RoutineHandshake() {
// TODO: Discover destination address also, only update on change
peer.mutex.Lock()
peer.endpoint = elem.source
peer.endpoint = elem.endpoint
peer.mutex.Unlock()
// create response
@ -460,8 +458,7 @@ func (device *Device) RoutineHandshake() {
if peer == nil {
logInfo.Println(
"Recieved invalid response message from",
elem.source.IP.String(),
elem.source.Port,
elem.endpoint.DestinationToString(),
)
continue
}