1// Copyright 2016 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
5package ipv4
6
7import (
8	"net"
9	"syscall"
10	"unsafe"
11
12	"golang.org/x/net/internal/iana"
13	"golang.org/x/net/internal/socket"
14
15	"golang.org/x/sys/unix"
16)
17
18const sockoptReceiveInterface = unix.IP_RECVIF
19
20var (
21	ctlOpts = [ctlMax]ctlOpt{
22		ctlTTL:        {unix.IP_RECVTTL, 4, marshalTTL, parseTTL},
23		ctlPacketInfo: {unix.IP_PKTINFO, sizeofInetPktinfo, marshalPacketInfo, parsePacketInfo},
24	}
25
26	sockOpts = map[int]sockOpt{
27		ssoTOS:                {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_TOS, Len: 4}},
28		ssoTTL:                {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_TTL, Len: 4}},
29		ssoMulticastTTL:       {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_TTL, Len: 1}},
30		ssoMulticastInterface: {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_IF, Len: 4}},
31		ssoMulticastLoopback:  {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_LOOP, Len: 1}},
32		ssoReceiveTTL:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVTTL, Len: 4}},
33		ssoPacketInfo:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVPKTINFO, Len: 4}},
34		ssoHeaderPrepend:      {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_HDRINCL, Len: 4}},
35		ssoJoinGroup:          {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_JOIN_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq},
36		ssoLeaveGroup:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_LEAVE_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq},
37		ssoJoinSourceGroup:    {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_JOIN_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
38		ssoLeaveSourceGroup:   {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_LEAVE_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
39		ssoBlockSourceGroup:   {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_BLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
40		ssoUnblockSourceGroup: {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_UNBLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
41	}
42)
43
44func (pi *inetPktinfo) setIfindex(i int) {
45	pi.Ifindex = uint32(i)
46}
47
48func (gr *groupReq) setGroup(grp net.IP) {
49	sa := (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gr)) + 4))
50	sa.Family = syscall.AF_INET
51	copy(sa.Addr[:], grp)
52}
53
54func (gsr *groupSourceReq) setSourceGroup(grp, src net.IP) {
55	sa := (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gsr)) + 4))
56	sa.Family = syscall.AF_INET
57	copy(sa.Addr[:], grp)
58	sa = (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gsr)) + 260))
59	sa.Family = syscall.AF_INET
60	copy(sa.Addr[:], src)
61}
62