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
18var (
19	ctlOpts = [ctlMax]ctlOpt{
20		ctlTTL:       {sysIP_RECVTTL, 1, marshalTTL, parseTTL},
21		ctlDst:       {sysIP_RECVDSTADDR, net.IPv4len, marshalDst, parseDst},
22		ctlInterface: {sysIP_RECVIF, syscall.SizeofSockaddrDatalink, marshalInterface, parseInterface},
23	}
24
25	sockOpts = map[int]*sockOpt{
26		ssoTOS:                {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_TOS, Len: 4}},
27		ssoTTL:                {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_TTL, Len: 4}},
28		ssoMulticastTTL:       {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_MULTICAST_TTL, Len: 1}},
29		ssoMulticastInterface: {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_MULTICAST_IF, Len: 4}},
30		ssoMulticastLoopback:  {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_MULTICAST_LOOP, Len: 4}},
31		ssoReceiveTTL:         {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_RECVTTL, Len: 4}},
32		ssoReceiveDst:         {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_RECVDSTADDR, Len: 4}},
33		ssoReceiveInterface:   {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_RECVIF, Len: 4}},
34		ssoHeaderPrepend:      {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_HDRINCL, Len: 4}},
35		ssoJoinGroup:          {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_JOIN_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq},
36		ssoLeaveGroup:         {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_LEAVE_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq},
37		ssoJoinSourceGroup:    {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_JOIN_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
38		ssoLeaveSourceGroup:   {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_LEAVE_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
39		ssoBlockSourceGroup:   {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_BLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
40		ssoUnblockSourceGroup: {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_UNBLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
41	}
42)
43
44func init() {
45	freebsdVersion, _ = syscall.SysctlUint32("kern.osreldate")
46	if freebsdVersion >= 1000000 {
47		sockOpts[ssoMulticastInterface] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_MULTICAST_IF, Len: sizeofIPMreqn}, typ: ssoTypeIPMreqn}
48	}
49	if runtime.GOOS == "freebsd" && runtime.GOARCH == "386" {
50		archs, _ := syscall.Sysctl("kern.supported_archs")
51		for _, s := range strings.Fields(archs) {
52			if s == "amd64" {
53				compatFreeBSD32 = true
54				break
55			}
56		}
57	}
58}
59
60func (gr *groupReq) setGroup(grp net.IP) {
61	sa := (*sockaddrInet)(unsafe.Pointer(&gr.Group))
62	sa.Len = sizeofSockaddrInet
63	sa.Family = syscall.AF_INET
64	copy(sa.Addr[:], grp)
65}
66
67func (gsr *groupSourceReq) setSourceGroup(grp, src net.IP) {
68	sa := (*sockaddrInet)(unsafe.Pointer(&gsr.Group))
69	sa.Len = sizeofSockaddrInet
70	sa.Family = syscall.AF_INET
71	copy(sa.Addr[:], grp)
72	sa = (*sockaddrInet)(unsafe.Pointer(&gsr.Source))
73	sa.Len = sizeofSockaddrInet
74	sa.Family = syscall.AF_INET
75	copy(sa.Addr[:], src)
76}
77