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package tunservice
import (
"encoding/binary"
"fmt"
"net"
"net/netip"
"os"
"testing"
)
// procWord writes 4 bytes of an address as /proc/net does on this machine.
func procWord(b []byte) string { return fmt.Sprintf("%08X", binary.NativeEndian.Uint32(b)) }
func TestProcNetAddressesAreRead(t *testing.T) {
v4 := netip.MustParseAddr("198.18.0.1").As4()
v6 := netip.MustParseAddr("fdfe:dcba:9876::1").As16()
var hex6 string
for i := 0; i < 16; i += 4 {
hex6 += procWord(v6[i : i+4])
}
for s, want := range map[string]string{
procWord(v4[:]) + ":C350": "198.18.0.1:50000",
hex6 + ":0050": "[fdfe:dcba:9876::1]:80",
} {
got, ok := parseProcAddr(s)
if !ok || got.String() != want {
t.Errorf("parseProcAddr(%q) = %s %v, want %s", s, got, ok, want)
}
}
for _, bad := range []string{"", "0100007F", "XYZ:0050", "0100007F:XYZ", "01007F:0050"} {
if _, ok := parseProcAddr(bad); ok {
t.Errorf("parseProcAddr(%q) read an address", bad)
}
}
}
func TestASocketIsFoundInATable(t *testing.T) {
lo := netip.MustParseAddr("198.18.0.1").As4()
any4 := [4]byte{}
table := fmt.Sprintf(` sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode
0: %s:C350 08080808:0035 01 00000000:00000000 00:00000000 00000000 1000 0 4242 1 0000000000000000 100 0 0 10 0
1: %s:C351 00000000:0000 07 00000000:00000000 00:00000000 00000000 999 0 4343 2 0000000000000000 0
`, procWord(lo[:]), procWord(any4[:]))
if inode, uid, ok := findSocket([]byte(table), false, netip.MustParseAddrPort("198.18.0.1:50000")); !ok || inode != 4242 || uid != 1000 {
t.Errorf("TCP: %d %d %v", inode, uid, ok)
}
// A UDP socket bound to any address answers for every address.
if inode, uid, ok := findSocket([]byte(table), true, netip.MustParseAddrPort("198.18.0.1:50001")); !ok || inode != 4343 || uid != 999 {
t.Errorf("UDP on any address: %d %d %v", inode, uid, ok)
}
if _, _, ok := findSocket([]byte(table), false, netip.MustParseAddrPort("198.18.0.1:50001")); ok {
t.Error("a TCP socket on any address was taken for one with an address")
}
}
// The program of a connection is found by its local address: this test's
// own TCP connection and UDP socket.
func TestTheProgramOfAConnectionIsFound(t *testing.T) {
self, err := os.Executable()
if err != nil {
t.Fatal(err)
}
ln, err := net.Listen("tcp4", "127.0.0.1:0")
if err != nil {
t.Fatal(err)
}
defer ln.Close()
c, err := net.Dial("tcp4", ln.Addr().String())
if err != nil {
t.Fatal(err)
}
defer c.Close()
u, err := net.ListenUDP("udp4", &net.UDPAddr{})
if err != nil {
t.Fatal(err)
}
defer u.Close()
for _, s := range []struct {
udp bool
addr netip.AddrPort
}{
{false, c.LocalAddr().(*net.TCPAddr).AddrPort()},
{true, netip.AddrPortFrom(netip.MustParseAddr("198.18.0.1"), u.LocalAddr().(*net.UDPAddr).AddrPort().Port())},
} {
path, err := ownerPath(s.udp, s.addr)
if err != nil || path != self {
t.Errorf("udp=%v %s: %q %v, want %q", s.udp, s.addr, path, err, self)
}
}
if path, err := ownerPath(false, netip.MustParseAddrPort("198.18.0.1:1")); err == nil {
t.Errorf("a socket nobody has was found: %q", path)
}
}
arblant