Fix Linux process search matching the wrong socket

2026-09-21 23:46:51 +00:00 · 2026-09-06 15:51:35 +08:00
parent 288411b0b9
commit 4ef3432c0d
3 changed files with 234 additions and 28 deletions
@@ -0,0 +1,108 @@
+//go:build linux
+
+package process
+
+import (
+	"context"
+	"net"
+	"net/netip"
+	"os"
+	"syscall"
+	"testing"
+
+	"github.com/sagernet/sing-box/log"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+
+	"github.com/stretchr/testify/require"
+)
+
+func socketInode(t *testing.T, conn syscall.Conn) uint32 {
+	rawConn, err := conn.SyscallConn()
+	require.NoError(t, err)
+	var inode uint32
+	err = rawConn.Control(func(fd uintptr) {
+		var stat syscall.Stat_t
+		require.NoError(t, syscall.Fstat(int(fd), &stat))
+		inode = uint32(stat.Ino)
+	})
+	require.NoError(t, err)
+	return inode
+}
+
+func TestDumpSocketDiagTCP(t *testing.T) {
+	t.Parallel()
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	require.NoError(t, err)
+	defer listener.Close()
+	first, err := (&net.Dialer{LocalAddr: &net.TCPAddr{IP: net.IPv4(127, 0, 0, 2)}}).Dial("tcp", listener.Addr().String())
+	require.NoError(t, err)
+	defer first.Close()
+	second, err := (&net.Dialer{LocalAddr: &net.TCPAddr{IP: net.IPv4(127, 0, 0, 3), Port: int(M.AddrPortFromNet(first.LocalAddr()).Port())}}).Dial("tcp", listener.Addr().String())
+	require.NoError(t, err)
+	defer second.Close()
+	destination := M.AddrPortFromNet(listener.Addr())
+	for _, conn := range []net.Conn{second, first} {
+		inode, uid, err := dumpSocketDiag(syscall.AF_INET, syscall.IPPROTO_TCP, M.AddrPortFromNet(conn.LocalAddr()), destination)
+		require.NoError(t, err)
+		require.Equal(t, socketInode(t, conn.(syscall.Conn)), inode)
+		require.Equal(t, uint32(os.Getuid()), uid)
+		inode, _, err = dumpSocketDiag(syscall.AF_INET, syscall.IPPROTO_TCP, M.AddrPortFromNet(conn.LocalAddr()), netip.AddrPort{})
+		require.NoError(t, err)
+		require.Equal(t, socketInode(t, conn.(syscall.Conn)), inode)
+	}
+	_, _, err = dumpSocketDiag(syscall.AF_INET, syscall.IPPROTO_TCP, netip.AddrPortFrom(netip.AddrFrom4([4]byte{127, 0, 0, 4}), M.AddrPortFromNet(first.LocalAddr()).Port()), destination)
+	require.ErrorIs(t, err, ErrNotFound)
+}
+
+func TestDumpSocketDiagUDP(t *testing.T) {
+	t.Parallel()
+	first, err := net.ListenUDP("udp4", &net.UDPAddr{IP: net.IPv4(127, 0, 0, 2)})
+	require.NoError(t, err)
+	defer first.Close()
+	port := M.AddrPortFromNet(first.LocalAddr()).Port()
+	second, err := net.ListenUDP("udp4", &net.UDPAddr{IP: net.IPv4(127, 0, 0, 3), Port: int(port)})
+	require.NoError(t, err)
+	defer second.Close()
+	for _, conn := range []*net.UDPConn{second, first} {
+		inode, _, err := dumpSocketDiag(syscall.AF_INET, syscall.IPPROTO_UDP, M.AddrPortFromNet(conn.LocalAddr()), netip.AddrPort{})
+		require.NoError(t, err)
+		require.Equal(t, socketInode(t, conn), inode)
+	}
+	_, _, err = dumpSocketDiag(syscall.AF_INET, syscall.IPPROTO_UDP, netip.AddrPortFrom(netip.AddrFrom4([4]byte{127, 0, 0, 4}), port), netip.AddrPort{})
+	require.ErrorIs(t, err, ErrNotFound)
+
+	wildcard, err := net.ListenUDP("udp4", &net.UDPAddr{})
+	require.NoError(t, err)
+	defer wildcard.Close()
+	inode, _, err := dumpSocketDiag(syscall.AF_INET, syscall.IPPROTO_UDP, netip.AddrPortFrom(netip.AddrFrom4([4]byte{127, 0, 0, 4}), M.AddrPortFromNet(wildcard.LocalAddr()).Port()), netip.AddrPort{})
+	require.NoError(t, err)
+	require.Equal(t, socketInode(t, wildcard), inode)
+}
+
+func TestLinuxSearcherFindProcessInfo(t *testing.T) {
+	t.Parallel()
+	searcher, err := NewSearcher(Config{Logger: log.NewNOPFactory().NewLogger("test")})
+	require.NoError(t, err)
+	defer searcher.Close()
+	executable, err := os.Executable()
+	require.NoError(t, err)
+
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	require.NoError(t, err)
+	defer listener.Close()
+	tcpConn, err := net.Dial("tcp", listener.Addr().String())
+	require.NoError(t, err)
+	defer tcpConn.Close()
+	info, err := searcher.FindProcessInfo(context.Background(), N.NetworkTCP, M.AddrPortFromNet(tcpConn.LocalAddr()), M.AddrPortFromNet(listener.Addr()))
+	require.NoError(t, err)
+	require.Equal(t, executable, info.ProcessPath)
+	require.Equal(t, int32(os.Getuid()), info.UserId)
+
+	udpConn, err := net.ListenUDP("udp4", &net.UDPAddr{})
+	require.NoError(t, err)
+	defer udpConn.Close()
+	info, err = searcher.FindProcessInfo(context.Background(), N.NetworkUDP, netip.AddrPortFrom(netip.AddrFrom4([4]byte{127, 0, 0, 1}), M.AddrPortFromNet(udpConn.LocalAddr()).Port()), netip.AddrPortFrom(netip.AddrFrom4([4]byte{127, 0, 0, 1}), 53))
+	require.NoError(t, err)
+	require.Equal(t, executable, info.ProcessPath)
+}