// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package ipv4
import (
"net"
"syscall"
"unsafe"
)
var (
ctlOpts = [ctlMax]ctlOpt{
ctlTTL: {sysIP_RECVTTL, 1, marshalTTL, parseTTL},
ctlDst: {sysIP_RECVDSTADDR, net.IPv4len, marshalDst, parseDst},
ctlInterface: {sysIP_RECVIF, syscall.SizeofSockaddrDatalink, marshalInterface, parseInterface},
}
sockOpts = [ssoMax]sockOpt{
ssoTOS: {sysIP_TOS, ssoTypeInt},
ssoTTL: {sysIP_TTL, ssoTypeInt},
ssoMulticastTTL: {sysIP_MULTICAST_TTL, ssoTypeByte},
ssoMulticastInterface: {sysIP_MULTICAST_IF, ssoTypeInterface},
ssoMulticastLoopback: {sysIP_MULTICAST_LOOP, ssoTypeInt},
ssoReceiveTTL: {sysIP_RECVTTL, ssoTypeInt},
ssoReceiveDst: {sysIP_RECVDSTADDR, ssoTypeInt},
ssoReceiveInterface: {sysIP_RECVIF, ssoTypeInt},
ssoHeaderPrepend: {sysIP_HDRINCL, ssoTypeInt},
ssoStripHeader: {sysIP_STRIPHDR, ssoTypeInt},
ssoJoinGroup: {sysIP_ADD_MEMBERSHIP, ssoTypeIPMreq},
ssoLeaveGroup: {sysIP_DROP_MEMBERSHIP, ssoTypeIPMreq},
}
)
func init() {
// Seems like kern.osreldate is veiled on latest OS X. We use
// kern.osrelease instead.
osver, err := syscall.Sysctl("kern.osrelease")
if err != nil {
return
}
var i int
for i = range osver {
if osver[i] == '.' {
break
}
}
// The IP_PKTINFO and protocol-independent multicast API were
// introduced in OS X 10.7 (Darwin 11.0.0). But it looks like
// those features require OS X 10.8 (Darwin 12.0.0) and above.
// See http://support.apple.com/kb/HT1633.
if i > 2 || i == 2 && osver[0] >= '1' && osver[1] >= '2' {
ctlOpts[ctlPacketInfo].name = sysIP_PKTINFO
ctlOpts[ctlPacketInfo].length = sysSizeofInetPktinfo
ctlOpts[ctlPacketInfo].marshal = marshalPacketInfo
ctlOpts[ctlPacketInfo].parse = parsePacketInfo
sockOpts[ssoPacketInfo].name = sysIP_RECVPKTINFO
sockOpts[ssoPacketInfo].typ = ssoTypeInt
sockOpts[ssoMulticastInterface].typ = ssoTypeIPMreqn
sockOpts[ssoJoinGroup].name = sysMCAST_JOIN_GROUP
sockOpts[ssoJoinGroup].typ = ssoTypeGroupReq
sockOpts[ssoLeaveGroup].name = sysMCAST_LEAVE_GROUP
sockOpts[ssoLeaveGroup].typ = ssoTypeGroupReq
sockOpts[ssoJoinSourceGroup].name = sysMCAST_JOIN_SOURCE_GROUP
sockOpts[ssoJoinSourceGroup].typ = ssoTypeGroupSourceReq
sockOpts[ssoLeaveSourceGroup].name = sysMCAST_LEAVE_SOURCE_GROUP
sockOpts[ssoLeaveSourceGroup].typ = ssoTypeGroupSourceReq
sockOpts[ssoBlockSourceGroup].name = sysMCAST_BLOCK_SOURCE
sockOpts[ssoBlockSourceGroup].typ = ssoTypeGroupSourceReq
sockOpts[ssoUnblockSourceGroup].name = sysMCAST_UNBLOCK_SOURCE
sockOpts[ssoUnblockSourceGroup].typ = ssoTypeGroupSourceReq
}
}
func (pi *sysInetPktinfo) setIfindex(i int) {
pi.Ifindex = uint32(i)
}
func (gr *sysGroupReq) setGroup(grp net.IP) {
sa := (*sysSockaddrInet)(unsafe.Pointer(&gr.Pad_cgo_0[0]))
sa.Len = sysSizeofSockaddrInet
sa.Family = syscall.AF_INET
copy(sa.Addr[:], grp)
}
func (gsr *sysGroupSourceReq) setSourceGroup(grp, src net.IP) {
sa := (*sysSockaddrInet)(unsafe.Pointer(&gsr.Pad_cgo_0[0]))
sa.Len = sysSizeofSockaddrInet
sa.Family = syscall.AF_INET
copy(sa.Addr[:], grp)
sa = (*sysSockaddrInet)(unsafe.Pointer(&gsr.Pad_cgo_1[0]))
sa.Len = sysSizeofSockaddrInet
sa.Family = syscall.AF_INET
copy(sa.Addr[:], src)
}