Chore: improve redir getorigdst

This commit is contained in:
Dreamacro 2022-12-22 12:00:56 +08:00
parent 90b40a8e5a
commit a6c144038b

View file

@ -1,12 +1,16 @@
package redir package redir
import ( import (
"encoding/binary"
"errors" "errors"
"net" "net"
"net/netip"
"syscall" "syscall"
"unsafe" "unsafe"
"github.com/Dreamacro/clash/transport/socks5" "github.com/Dreamacro/clash/transport/socks5"
"golang.org/x/sys/unix"
) )
const ( const (
@ -25,27 +29,22 @@ func parserPacket(conn net.Conn) (socks5.Addr, error) {
return nil, err return nil, err
} }
var addr socks5.Addr var addr netip.AddrPort
rc.Control(func(fd uintptr) { rc.Control(func(fd uintptr) {
addr, err = getorigdst(fd) addr, err = getorigdst(fd)
}) })
return addr, err return socks5.AddrFromStdAddrPort(addr), err
} }
// Call getorigdst() from linux/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c // Call getorigdst() from linux/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
func getorigdst(fd uintptr) (socks5.Addr, error) { func getorigdst(fd uintptr) (netip.AddrPort, error) {
raw := syscall.RawSockaddrInet4{} addr := unix.RawSockaddrInet4{}
siz := uint32(unsafe.Sizeof(raw)) size := uint32(unsafe.Sizeof(addr))
if err := socketcall(GETSOCKOPT, fd, syscall.IPPROTO_IP, SO_ORIGINAL_DST, uintptr(unsafe.Pointer(&raw)), uintptr(unsafe.Pointer(&siz)), 0); err != nil { if err := socketcall(GETSOCKOPT, fd, syscall.IPPROTO_IP, SO_ORIGINAL_DST, uintptr(unsafe.Pointer(&addr)), uintptr(unsafe.Pointer(&size)), 0); err != nil {
return nil, err return netip.AddrPort{}, err
} }
port := binary.BigEndian.Uint16((*(*[2]byte)(unsafe.Pointer(&addr.Port)))[:])
addr := make([]byte, 1+net.IPv4len+2) return netip.AddrPortFrom(netip.AddrFrom4(addr.Addr), port), nil
addr[0] = socks5.AtypIPv4
copy(addr[1:1+net.IPv4len], raw.Addr[:])
port := (*[2]byte)(unsafe.Pointer(&raw.Port)) // big-endian
addr[1+net.IPv4len], addr[1+net.IPv4len+1] = port[0], port[1]
return addr, nil
} }