David K. Bainbridge | 215e024 | 2017-09-05 23:18:24 -0700 | [diff] [blame] | 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 | |
| 5 | package ipv4 |
| 6 | |
| 7 | import ( |
| 8 | "net" |
| 9 | "strconv" |
| 10 | "strings" |
| 11 | "syscall" |
| 12 | "unsafe" |
| 13 | |
| 14 | "golang.org/x/net/internal/iana" |
| 15 | "golang.org/x/net/internal/socket" |
| 16 | ) |
| 17 | |
| 18 | var ( |
| 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 | ssoStripHeader: {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_STRIPHDR, Len: 4}}, |
| 36 | ssoJoinGroup: {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_ADD_MEMBERSHIP, Len: sizeofIPMreq}, typ: ssoTypeIPMreq}, |
| 37 | ssoLeaveGroup: {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_DROP_MEMBERSHIP, Len: sizeofIPMreq}, typ: ssoTypeIPMreq}, |
| 38 | } |
| 39 | ) |
| 40 | |
| 41 | func init() { |
| 42 | // Seems like kern.osreldate is veiled on latest OS X. We use |
| 43 | // kern.osrelease instead. |
| 44 | s, err := syscall.Sysctl("kern.osrelease") |
| 45 | if err != nil { |
| 46 | return |
| 47 | } |
| 48 | ss := strings.Split(s, ".") |
| 49 | if len(ss) == 0 { |
| 50 | return |
| 51 | } |
| 52 | // The IP_PKTINFO and protocol-independent multicast API were |
| 53 | // introduced in OS X 10.7 (Darwin 11). But it looks like |
| 54 | // those features require OS X 10.8 (Darwin 12) or above. |
| 55 | // See http://support.apple.com/kb/HT1633. |
| 56 | if mjver, err := strconv.Atoi(ss[0]); err != nil || mjver < 12 { |
| 57 | return |
| 58 | } |
| 59 | ctlOpts[ctlPacketInfo].name = sysIP_PKTINFO |
| 60 | ctlOpts[ctlPacketInfo].length = sizeofInetPktinfo |
| 61 | ctlOpts[ctlPacketInfo].marshal = marshalPacketInfo |
| 62 | ctlOpts[ctlPacketInfo].parse = parsePacketInfo |
| 63 | sockOpts[ssoPacketInfo] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_RECVPKTINFO, Len: 4}} |
| 64 | sockOpts[ssoMulticastInterface] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_MULTICAST_IF, Len: sizeofIPMreqn}, typ: ssoTypeIPMreqn} |
| 65 | sockOpts[ssoJoinGroup] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_JOIN_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq} |
| 66 | sockOpts[ssoLeaveGroup] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_LEAVE_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq} |
| 67 | sockOpts[ssoJoinSourceGroup] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_JOIN_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq} |
| 68 | sockOpts[ssoLeaveSourceGroup] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_LEAVE_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq} |
| 69 | sockOpts[ssoBlockSourceGroup] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_BLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq} |
| 70 | sockOpts[ssoUnblockSourceGroup] = &sockOpt{Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_UNBLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq} |
| 71 | } |
| 72 | |
| 73 | func (pi *inetPktinfo) setIfindex(i int) { |
| 74 | pi.Ifindex = uint32(i) |
| 75 | } |
| 76 | |
| 77 | func (gr *groupReq) setGroup(grp net.IP) { |
| 78 | sa := (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gr)) + 4)) |
| 79 | sa.Len = sizeofSockaddrInet |
| 80 | sa.Family = syscall.AF_INET |
| 81 | copy(sa.Addr[:], grp) |
| 82 | } |
| 83 | |
| 84 | func (gsr *groupSourceReq) setSourceGroup(grp, src net.IP) { |
| 85 | sa := (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gsr)) + 4)) |
| 86 | sa.Len = sizeofSockaddrInet |
| 87 | sa.Family = syscall.AF_INET |
| 88 | copy(sa.Addr[:], grp) |
| 89 | sa = (*sockaddrInet)(unsafe.Pointer(uintptr(unsafe.Pointer(gsr)) + 132)) |
| 90 | sa.Len = sizeofSockaddrInet |
| 91 | sa.Family = syscall.AF_INET |
| 92 | copy(sa.Addr[:], src) |
| 93 | } |