1// Copyright 2014 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, 1, marshalTTL, parseTTL},
23		ctlDst:        {unix.IP_RECVDSTADDR, net.IPv4len, marshalDst, parseDst},
24		ctlInterface:  {unix.IP_RECVIF, syscall.SizeofSockaddrDatalink, marshalInterface, parseInterface},
25		ctlPacketInfo: {unix.IP_PKTINFO, sizeofInetPktinfo, marshalPacketInfo, parsePacketInfo},
26	}
27
28	sockOpts = map[int]*sockOpt{
29		ssoTOS:                {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_TOS, Len: 4}},
30		ssoTTL:                {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_TTL, Len: 4}},
31		ssoMulticastTTL:       {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_TTL, Len: 1}},
32		ssoMulticastInterface: {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_IF, Len: unix.SizeofIPMreqn}, typ: ssoTypeIPMreqn},
33		ssoMulticastLoopback:  {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_LOOP, Len: 4}},
34		ssoReceiveTTL:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVTTL, Len: 4}},
35		ssoReceiveDst:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVDSTADDR, Len: 4}},
36		ssoReceiveInterface:   {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVIF, Len: 4}},
37		ssoHeaderPrepend:      {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_HDRINCL, Len: 4}},
38		ssoStripHeader:        {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_STRIPHDR, Len: 4}},
39		ssoJoinGroup:          {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_JOIN_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq},
40		ssoLeaveGroup:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_LEAVE_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq},
41		ssoJoinSourceGroup:    {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_JOIN_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
42		ssoLeaveSourceGroup:   {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_LEAVE_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
43		ssoBlockSourceGroup:   {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_BLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
44		ssoUnblockSourceGroup: {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.MCAST_UNBLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
45		ssoPacketInfo:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVPKTINFO, Len: 4}},
46	}
47)
48
49func (pi *inetPktinfo) setIfindex(i int) {
50	pi.Ifindex = uint32(i)
51}
52
53func (gr *groupReq) setGroup(grp net.IP) {
54	sa := (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gr)) + 4))
55	sa.Len = sizeofSockaddrInet
56	sa.Family = syscall.AF_INET
57	copy(sa.Addr[:], grp)
58}
59
60func (gsr *groupSourceReq) setSourceGroup(grp, src net.IP) {
61	sa := (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gsr)) + 4))
62	sa.Len = sizeofSockaddrInet
63	sa.Family = syscall.AF_INET
64	copy(sa.Addr[:], grp)
65	sa = (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gsr)) + 132))
66	sa.Len = sizeofSockaddrInet
67	sa.Family = syscall.AF_INET
68	copy(sa.Addr[:], src)
69}
70