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	"runtime"
10	"strings"
11	"syscall"
12	"unsafe"
13
14	"golang.org/x/net/internal/iana"
15	"golang.org/x/net/internal/socket"
16
17	"golang.org/x/sys/unix"
18)
19
20const sockoptReceiveInterface = unix.IP_RECVIF
21
22var (
23	ctlOpts = [ctlMax]ctlOpt{
24		ctlTTL:       {unix.IP_RECVTTL, 1, marshalTTL, parseTTL},
25		ctlDst:       {unix.IP_RECVDSTADDR, net.IPv4len, marshalDst, parseDst},
26		ctlInterface: {unix.IP_RECVIF, syscall.SizeofSockaddrDatalink, marshalInterface, parseInterface},
27	}
28
29	sockOpts = map[int]*sockOpt{
30		ssoTOS:                {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_TOS, Len: 4}},
31		ssoTTL:                {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_TTL, Len: 4}},
32		ssoMulticastTTL:       {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_TTL, Len: 1}},
33		ssoMulticastInterface: {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_IF, Len: 4}},
34		ssoMulticastLoopback:  {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_LOOP, Len: 4}},
35		ssoReceiveTTL:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVTTL, Len: 4}},
36		ssoReceiveDst:         {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVDSTADDR, Len: 4}},
37		ssoReceiveInterface:   {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_RECVIF, Len: 4}},
38		ssoHeaderPrepend:      {Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_HDRINCL, 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	}
46)
47
48func init() {
49	freebsdVersion, _ = syscall.SysctlUint32("kern.osreldate")
50	if freebsdVersion >= 1000000 {
51		sockOpts[ssoMulticastInterface] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: unix.IP_MULTICAST_IF, Len: unix.SizeofIPMreqn}, typ: ssoTypeIPMreqn}
52	}
53	if runtime.GOOS == "freebsd" && runtime.GOARCH == "386" {
54		archs, _ := syscall.Sysctl("kern.supported_archs")
55		for _, s := range strings.Fields(archs) {
56			if s == "amd64" {
57				compatFreeBSD32 = true
58				break
59			}
60		}
61	}
62}
63
64func (gr *groupReq) setGroup(grp net.IP) {
65	sa := (*sockaddrInet)(unsafe.Pointer(&gr.Group))
66	sa.Len = sizeofSockaddrInet
67	sa.Family = syscall.AF_INET
68	copy(sa.Addr[:], grp)
69}
70
71func (gsr *groupSourceReq) setSourceGroup(grp, src net.IP) {
72	sa := (*sockaddrInet)(unsafe.Pointer(&gsr.Group))
73	sa.Len = sizeofSockaddrInet
74	sa.Family = syscall.AF_INET
75	copy(sa.Addr[:], grp)
76	sa = (*sockaddrInet)(unsafe.Pointer(&gsr.Source))
77	sa.Len = sizeofSockaddrInet
78	sa.Family = syscall.AF_INET
79	copy(sa.Addr[:], src)
80}
81