Files
visor/test/iptables/iptables_unsafe.go
Ayush RanjanandgVisor bot c650f6a0e7 [op] Replace syscall package usage with golang.org/x/sys/unix in test/.
The syscall package has been deprecated in favor of golang.org/x/sys.

Note that syscall is still used in some places because the following don't seem
to have an equivalent in unix package:
- syscall.SysProcIDMap
- syscall.Credential

Updates #214

PiperOrigin-RevId: 361332034
2021-03-06 09:54:09 -08:00

65 lines
1.9 KiB
Go

// Copyright 2020 The gVisor Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package iptables
import (
"fmt"
"unsafe"
"golang.org/x/sys/unix"
)
type originalDstError struct {
errno unix.Errno
}
func (e originalDstError) Error() string {
return fmt.Sprintf("errno (%d) when calling getsockopt(SO_ORIGINAL_DST): %v", int(e.errno), e.errno.Error())
}
// SO_ORIGINAL_DST gets the original destination of a redirected packet via
// getsockopt.
const SO_ORIGINAL_DST = 80
func originalDestination4(connfd int) (unix.RawSockaddrInet4, error) {
var addr unix.RawSockaddrInet4
var addrLen uint32 = unix.SizeofSockaddrInet4
if errno := originalDestination(connfd, unix.SOL_IP, unsafe.Pointer(&addr), &addrLen); errno != 0 {
return unix.RawSockaddrInet4{}, originalDstError{errno}
}
return addr, nil
}
func originalDestination6(connfd int) (unix.RawSockaddrInet6, error) {
var addr unix.RawSockaddrInet6
var addrLen uint32 = unix.SizeofSockaddrInet6
if errno := originalDestination(connfd, unix.SOL_IPV6, unsafe.Pointer(&addr), &addrLen); errno != 0 {
return unix.RawSockaddrInet6{}, originalDstError{errno}
}
return addr, nil
}
func originalDestination(connfd int, level uintptr, optval unsafe.Pointer, optlen *uint32) unix.Errno {
_, _, errno := unix.Syscall6(
unix.SYS_GETSOCKOPT,
uintptr(connfd),
level,
SO_ORIGINAL_DST,
uintptr(optval),
uintptr(unsafe.Pointer(optlen)),
0)
return errno
}