sing-box/common/process/searcher_darwin.go
2022-07-30 09:04:01 +08:00

124 lines
2.6 KiB
Go

package process
import (
"context"
"encoding/binary"
"net/netip"
"os"
"syscall"
"unsafe"
"github.com/sagernet/sing-box/log"
N "github.com/sagernet/sing/common/network"
"golang.org/x/sys/unix"
)
var _ Searcher = (*darwinSearcher)(nil)
type darwinSearcher struct{}
func NewSearcher(logger log.ContextLogger) (Searcher, error) {
return &darwinSearcher{}, nil
}
func (d *darwinSearcher) FindProcessInfo(ctx context.Context, network string, srcIP netip.Addr, srcPort int) (*Info, error) {
processName, err := findProcessName(network, srcIP, srcPort)
if err != nil {
return nil, err
}
return &Info{ProcessPath: processName, UserId: -1}, nil
}
func findProcessName(network string, ip netip.Addr, port int) (string, error) {
var spath string
switch network {
case N.NetworkTCP:
spath = "net.inet.tcp.pcblist_n"
case N.NetworkUDP:
spath = "net.inet.udp.pcblist_n"
default:
return "", os.ErrInvalid
}
isIPv4 := ip.Is4()
value, err := syscall.Sysctl(spath)
if err != nil {
return "", err
}
buf := []byte(value)
// from darwin-xnu/bsd/netinet/in_pcblist.c:get_pcblist_n
// size/offset are round up (aligned) to 8 bytes in darwin
// rup8(sizeof(xinpcb_n)) + rup8(sizeof(xsocket_n)) +
// 2 * rup8(sizeof(xsockbuf_n)) + rup8(sizeof(xsockstat_n))
itemSize := 384
if network == N.NetworkTCP {
// rup8(sizeof(xtcpcb_n))
itemSize += 208
}
// skip the first xinpgen(24 bytes) block
for i := 24; i+itemSize <= len(buf); i += itemSize {
// offset of xinpcb_n and xsocket_n
inp, so := i, i+104
srcPort := binary.BigEndian.Uint16(buf[inp+18 : inp+20])
if uint16(port) != srcPort {
continue
}
// xinpcb_n.inp_vflag
flag := buf[inp+44]
var srcIP netip.Addr
switch {
case flag&0x1 > 0 && isIPv4:
// ipv4
srcIP = netip.AddrFrom4(*(*[4]byte)(buf[inp+76 : inp+80]))
case flag&0x2 > 0 && !isIPv4:
// ipv6
srcIP = netip.AddrFrom16(*(*[16]byte)(buf[inp+64 : inp+80]))
default:
continue
}
if ip != srcIP {
continue
}
// xsocket_n.so_last_pid
pid := readNativeUint32(buf[so+68 : so+72])
return getExecPathFromPID(pid)
}
return "", ErrNotFound
}
func getExecPathFromPID(pid uint32) (string, error) {
const (
procpidpathinfo = 0xb
procpidpathinfosize = 1024
proccallnumpidinfo = 0x2
)
buf := make([]byte, procpidpathinfosize)
_, _, errno := syscall.Syscall6(
syscall.SYS_PROC_INFO,
proccallnumpidinfo,
uintptr(pid),
procpidpathinfo,
0,
uintptr(unsafe.Pointer(&buf[0])),
procpidpathinfosize)
if errno != 0 {
return "", errno
}
return unix.ByteSliceToString(buf), nil
}
func readNativeUint32(b []byte) uint32 {
return *(*uint32)(unsafe.Pointer(&b[0]))
}