lsf_linux.mx raw

   1  // Copyright 2011 The Go Authors. All rights reserved.
   2  // Use of this source code is governed by a BSD-style
   3  // license that can be found in the LICENSE file.
   4  
   5  // Linux socket filter
   6  
   7  package syscall
   8  
   9  import (
  10  	"unsafe"
  11  )
  12  
  13  // Deprecated: Use golang.org/x/net/bpf instead.
  14  func LsfStmt(code, k int) *SockFilter {
  15  	return &SockFilter{Code: uint16(code), K: uint32(k)}
  16  }
  17  
  18  // Deprecated: Use golang.org/x/net/bpf instead.
  19  func LsfJump(code, k, jt, jf int) *SockFilter {
  20  	return &SockFilter{Code: uint16(code), Jt: uint8(jt), Jf: uint8(jf), K: uint32(k)}
  21  }
  22  
  23  // Deprecated: Use golang.org/x/net/bpf instead.
  24  func LsfSocket(ifindex, proto int) (int, error) {
  25  	var lsall SockaddrLinklayer
  26  	// This is missing SOCK_CLOEXEC, but adding the flag
  27  	// could break callers.
  28  	s, e := Socket(AF_PACKET, SOCK_RAW, proto)
  29  	if e != nil {
  30  		return 0, e
  31  	}
  32  	p := (*[2]byte)(unsafe.Pointer(&lsall.Protocol))
  33  	p[0] = byte(proto >> 8)
  34  	p[1] = byte(proto)
  35  	lsall.Ifindex = ifindex
  36  	e = Bind(s, &lsall)
  37  	if e != nil {
  38  		Close(s)
  39  		return 0, e
  40  	}
  41  	return s, nil
  42  }
  43  
  44  type iflags struct {
  45  	name  [IFNAMSIZ]byte
  46  	flags uint16
  47  }
  48  
  49  // Deprecated: Use golang.org/x/net/bpf instead.
  50  func SetLsfPromisc(name string, m bool) error {
  51  	s, e := Socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC, 0)
  52  	if e != nil {
  53  		return e
  54  	}
  55  	defer Close(s)
  56  	var ifl iflags
  57  	copy(ifl.name[:], []byte(name))
  58  	_, _, ep := Syscall(SYS_IOCTL, uintptr(s), SIOCGIFFLAGS, uintptr(unsafe.Pointer(&ifl)))
  59  	if ep != 0 {
  60  		return Errno(ep)
  61  	}
  62  	if m {
  63  		ifl.flags |= uint16(IFF_PROMISC)
  64  	} else {
  65  		ifl.flags &^= uint16(IFF_PROMISC)
  66  	}
  67  	_, _, ep = Syscall(SYS_IOCTL, uintptr(s), SIOCSIFFLAGS, uintptr(unsafe.Pointer(&ifl)))
  68  	if ep != 0 {
  69  		return Errno(ep)
  70  	}
  71  	return nil
  72  }
  73  
  74  // Deprecated: Use golang.org/x/net/bpf instead.
  75  func AttachLsf(fd int, i []SockFilter) error {
  76  	var p SockFprog
  77  	p.Len = uint16(len(i))
  78  	p.Filter = (*SockFilter)(unsafe.Pointer(&i[0]))
  79  	return setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, unsafe.Pointer(&p), unsafe.Sizeof(p))
  80  }
  81  
  82  // Deprecated: Use golang.org/x/net/bpf instead.
  83  func DetachLsf(fd int) error {
  84  	var dummy int
  85  	return setsockopt(fd, SOL_SOCKET, SO_DETACH_FILTER, unsafe.Pointer(&dummy), unsafe.Sizeof(dummy))
  86  }
  87