func marshalControlMessage(cm *ControlMessage) (oob []byte) {
if cm == nil {
return
}
l, off := 0, 0
pion := false
if cm.Src.To4() != nil || cm.IfIndex != 0 {
pion = true
l += syscall.CmsgSpace(syscall.SizeofInet4Pktinfo)
}
if l > 0 {
oob = make([]byte, l)
if pion {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIP
m.Type = syscall.IP_PKTINFO
m.SetLen(syscall.CmsgLen(syscall.SizeofInet4Pktinfo))
pi := (*syscall.Inet4Pktinfo)(unsafe.Pointer(&oob[off+syscall.CmsgLen(0)]))
if ip := cm.Src.To4(); ip != nil {
copy(pi.Addr[:], ip)
}
if cm.IfIndex != 0 {
pi.Ifindex = int32(cm.IfIndex)
}
off += syscall.CmsgSpace(syscall.SizeofInet4Pktinfo)
}
}
return
}
func newControlMessage(opt *rawOpt) (oob []byte) {
opt.Lock()
defer opt.Unlock()
l, off := 0, 0
if opt.isset(FlagHopLimit) {
l += syscall.CmsgSpace(4)
}
if opt.isset(pktinfo) {
l += syscall.CmsgSpace(sysSizeofPacketInfo)
}
if l > 0 {
oob = make([]byte, l)
if opt.isset(FlagHopLimit) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = sysSockopt2292HopLimit
m.SetLen(syscall.CmsgLen(4))
off += syscall.CmsgSpace(4)
}
if opt.isset(pktinfo) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = sysSockopt2292PacketInfo
m.SetLen(syscall.CmsgLen(sysSizeofPacketInfo))
off += syscall.CmsgSpace(sysSizeofPacketInfo)
}
}
return
}
func newControlMessage(opt *rawOpt) (oob []byte) {
opt.Lock()
defer opt.Unlock()
l, off := 0, 0
if opt.isset(FlagTTL) {
l += syscall.CmsgSpace(1)
}
if opt.isset(pktinfo) {
l += syscall.CmsgSpace(syscall.SizeofInet4Pktinfo)
}
if l > 0 {
oob = make([]byte, l)
if opt.isset(FlagTTL) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIP
m.Type = syscall.IP_RECVTTL
m.SetLen(syscall.CmsgLen(1))
off += syscall.CmsgSpace(1)
}
if opt.isset(pktinfo) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIP
m.Type = syscall.IP_PKTINFO
m.SetLen(syscall.CmsgLen(syscall.SizeofInet4Pktinfo))
off += syscall.CmsgSpace(syscall.SizeofInet4Pktinfo)
}
}
return
}
func newControlMessage(opt *rawOpt) (oob []byte) {
opt.RLock()
var l int
if opt.isset(FlagTrafficClass) && ctlOpts[ctlTrafficClass].name > 0 {
l += syscall.CmsgSpace(ctlOpts[ctlTrafficClass].length)
}
if opt.isset(FlagHopLimit) && ctlOpts[ctlHopLimit].name > 0 {
l += syscall.CmsgSpace(ctlOpts[ctlHopLimit].length)
}
if opt.isset(flagPacketInfo) && ctlOpts[ctlPacketInfo].name > 0 {
l += syscall.CmsgSpace(ctlOpts[ctlPacketInfo].length)
}
if opt.isset(FlagPathMTU) && ctlOpts[ctlPathMTU].name > 0 {
l += syscall.CmsgSpace(ctlOpts[ctlPathMTU].length)
}
if l > 0 {
oob = make([]byte, l)
b := oob
if opt.isset(FlagTrafficClass) && ctlOpts[ctlTrafficClass].name > 0 {
b = ctlOpts[ctlTrafficClass].marshal(b, nil)
}
if opt.isset(FlagHopLimit) && ctlOpts[ctlHopLimit].name > 0 {
b = ctlOpts[ctlHopLimit].marshal(b, nil)
}
if opt.isset(flagPacketInfo) && ctlOpts[ctlPacketInfo].name > 0 {
b = ctlOpts[ctlPacketInfo].marshal(b, nil)
}
if opt.isset(FlagPathMTU) && ctlOpts[ctlPathMTU].name > 0 {
b = ctlOpts[ctlPathMTU].marshal(b, nil)
}
}
opt.RUnlock()
return
}
func newControlMessage(opt *rawOpt) (oob []byte) {
opt.lock()
defer opt.unlock()
if opt.isset(FlagTTL) {
b := make([]byte, syscall.CmsgSpace(1))
cmsg := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
cmsg.Level = ianaProtocolIP
cmsg.Type = syscall.IP_RECVTTL
cmsg.SetLen(syscall.CmsgLen(1))
oob = append(oob, b...)
}
if opt.isset(FlagDst) {
b := make([]byte, syscall.CmsgSpace(net.IPv4len))
cmsg := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
cmsg.Level = ianaProtocolIP
cmsg.Type = syscall.IP_RECVDSTADDR
cmsg.SetLen(syscall.CmsgLen(net.IPv4len))
oob = append(oob, b...)
}
if opt.isset(FlagInterface) {
b := make([]byte, syscall.CmsgSpace(syscall.SizeofSockaddrDatalink))
cmsg := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
cmsg.Level = ianaProtocolIP
cmsg.Type = syscall.IP_RECVIF
cmsg.SetLen(syscall.CmsgLen(syscall.SizeofSockaddrDatalink))
oob = append(oob, b...)
}
return
}
func (opt *rawOpt) oobLen() (l int) {
if opt.isset(FlagTTL) {
l += syscall.CmsgSpace(1)
}
if opt.isset(FlagSrc | FlagDst | FlagInterface) {
l += syscall.CmsgSpace(sysSizeofPacketInfo)
}
return
}
func marshalTTL(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIP
m.Type = sysIP_RECVTTL
m.SetLen(syscall.CmsgLen(1))
return b[syscall.CmsgSpace(1):]
}
func marshalDst(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIP
m.Type = sysIP_RECVDSTADDR
m.SetLen(syscall.CmsgLen(net.IPv4len))
return b[syscall.CmsgSpace(net.IPv4len):]
}
func marshalInterface(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIP
m.Type = sysIP_RECVIF
m.SetLen(syscall.CmsgLen(syscall.SizeofSockaddrDatalink))
return b[syscall.CmsgSpace(syscall.SizeofSockaddrDatalink):]
}
func marshalControlMessage(cm *ControlMessage) (oob []byte) {
if cm == nil {
return
}
pi := &syscall.Inet4Pktinfo{}
pion := false
if ip := cm.Src.To4(); ip != nil {
copy(pi.Spec_dst[:], ip[:net.IPv4len])
pion = true
}
if cm.IfIndex != 0 {
pi.Ifindex = int32(cm.IfIndex)
pion = true
}
if pion {
b := make([]byte, syscall.CmsgSpace(syscall.SizeofInet4Pktinfo))
cmsg := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
cmsg.Level = ianaProtocolIP
cmsg.Type = syscall.IP_PKTINFO
cmsg.SetLen(syscall.CmsgLen(syscall.SizeofInet4Pktinfo))
data := b[syscall.CmsgLen(0):]
copy(data[:syscall.SizeofInet4Pktinfo], (*[syscall.SizeofInet4Pktinfo]byte)(unsafe.Pointer(pi))[:syscall.SizeofInet4Pktinfo])
oob = append(oob, b...)
}
return
}
func marshalPathMTU(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIPv6
m.Type = sysIPV6_PATHMTU
m.SetLen(syscall.CmsgLen(sysSizeofIPv6Mtuinfo))
return b[syscall.CmsgSpace(sysSizeofIPv6Mtuinfo):]
}
// http://golang.org/src/pkg/syscall/sockcmsg_linux.go
// UnixCredentials encodes credentials into a socket control message
// for sending to another process. This can be used for
// authentication.
func UnixCredentials(ucred *Ucred) []byte {
b := make([]byte, syscall.CmsgSpace(SizeofUcred))
h := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
h.Level = syscall.SOL_SOCKET
h.Type = syscall.SCM_CREDS
h.SetLen(syscall.CmsgLen(SizeofUcred))
*((*Ucred)(cmsgData(h))) = *ucred
return b
}
func (opt *rawOpt) oobLen() (l int) {
if opt.isset(FlagTTL) {
l += syscall.CmsgSpace(1)
}
if supportsPacketInfo {
if opt.isset(FlagSrc | FlagDst | FlagInterface) {
l += syscall.CmsgSpace(sysSizeofPacketInfo)
}
} else {
if opt.isset(FlagDst) {
l += syscall.CmsgSpace(net.IPv4len)
}
if opt.isset(FlagInterface) {
l += syscall.CmsgSpace(syscall.SizeofSockaddrDatalink)
}
}
return
}
func (opt *rawOpt) marshalControlMessage() (oob []byte) {
var off int
oob = make([]byte, opt.oobLen())
if opt.isset(FlagTTL) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIP
m.Type = sysSockoptReceiveTTL
m.SetLen(syscall.CmsgLen(1))
off += syscall.CmsgSpace(1)
}
if opt.isset(FlagSrc | FlagDst | FlagInterface) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[0]))
m.Level = ianaProtocolIP
m.Type = sysSockoptPacketInfo
m.SetLen(syscall.CmsgLen(sysSizeofPacketInfo))
off += syscall.CmsgSpace(sysSizeofPacketInfo)
}
return
}
func marshalControlMessage(cm *ControlMessage) (oob []byte) {
if cm == nil {
return
}
var l int
tclass := false
if ctlOpts[ctlTrafficClass].name > 0 && cm.TrafficClass > 0 {
tclass = true
l += syscall.CmsgSpace(ctlOpts[ctlTrafficClass].length)
}
hoplimit := false
if ctlOpts[ctlHopLimit].name > 0 && cm.HopLimit > 0 {
hoplimit = true
l += syscall.CmsgSpace(ctlOpts[ctlHopLimit].length)
}
pktinfo := false
if ctlOpts[ctlPacketInfo].name > 0 && (cm.Src.To16() != nil && cm.Src.To4() == nil || cm.IfIndex > 0) {
pktinfo = true
l += syscall.CmsgSpace(ctlOpts[ctlPacketInfo].length)
}
nexthop := false
if ctlOpts[ctlNextHop].name > 0 && cm.NextHop.To16() != nil && cm.NextHop.To4() == nil {
nexthop = true
l += syscall.CmsgSpace(ctlOpts[ctlNextHop].length)
}
if l > 0 {
oob = make([]byte, l)
b := oob
if tclass {
b = ctlOpts[ctlTrafficClass].marshal(b, cm)
}
if hoplimit {
b = ctlOpts[ctlHopLimit].marshal(b, cm)
}
if pktinfo {
b = ctlOpts[ctlPacketInfo].marshal(b, cm)
}
if nexthop {
b = ctlOpts[ctlNextHop].marshal(b, cm)
}
}
return
}
func marshalNextHop(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIPv6
m.Type = sysIPV6_NEXTHOP
m.SetLen(syscall.CmsgLen(sysSizeofSockaddrInet6))
if cm != nil {
sa := (*sysSockaddrInet6)(unsafe.Pointer(&b[syscall.CmsgLen(0)]))
sa.setSockaddr(cm.NextHop, cm.IfIndex)
}
return b[syscall.CmsgSpace(sysSizeofSockaddrInet6):]
}
func marshalHopLimit(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIPv6
m.Type = sysIPV6_HOPLIMIT
m.SetLen(syscall.CmsgLen(4))
if cm != nil {
data := b[syscall.CmsgLen(0):]
nativeEndian.PutUint32(data[:4], uint32(cm.HopLimit))
}
return b[syscall.CmsgSpace(4):]
}
func marshal2292HopLimit(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = ianaProtocolIPv6
m.Type = sysIPV6_2292HOPLIMIT
m.SetLen(syscall.CmsgLen(4))
if cm != nil {
data := b[syscall.CmsgLen(0):]
*(*int32)(unsafe.Pointer(&data[:4][0])) = int32(cm.HopLimit)
}
return b[syscall.CmsgSpace(4):]
}
func marshalHopLimit(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIPv6
m.Type = sysIPV6_HOPLIMIT
m.SetLen(syscall.CmsgLen(4))
if cm != nil {
data := b[syscall.CmsgLen(0):]
// TODO(mikio): fix potential misaligned memory access
*(*int32)(unsafe.Pointer(&data[:4][0])) = int32(cm.HopLimit)
}
return b[syscall.CmsgSpace(4):]
}
func newControlMessage(opt *rawOpt) (oob []byte) {
opt.lock()
defer opt.unlock()
if opt.isset(FlagTTL) {
b := make([]byte, syscall.CmsgSpace(1))
cmsg := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
cmsg.Level = ianaProtocolIP
cmsg.Type = syscall.IP_RECVTTL
cmsg.SetLen(syscall.CmsgLen(1))
oob = append(oob, b...)
}
if opt.isset(pktinfo) {
b := make([]byte, syscall.CmsgSpace(syscall.SizeofInet4Pktinfo))
cmsg := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
cmsg.Level = ianaProtocolIP
cmsg.Type = syscall.IP_PKTINFO
cmsg.SetLen(syscall.CmsgLen(syscall.SizeofInet4Pktinfo))
oob = append(oob, b...)
}
return
}
func newControlMessage(opt *rawOpt) (oob []byte) {
opt.RLock()
var l int
if opt.isset(FlagTTL) {
l += syscall.CmsgSpace(ctlOpts[ctlTTL].length)
}
if ctlOpts[ctlPacketInfo].name > 0 {
if opt.isset(FlagSrc | FlagDst | FlagInterface) {
l += syscall.CmsgSpace(ctlOpts[ctlPacketInfo].length)
}
} else {
if opt.isset(FlagDst) {
l += syscall.CmsgSpace(ctlOpts[ctlDst].length)
}
if opt.isset(FlagInterface) {
l += syscall.CmsgSpace(ctlOpts[ctlInterface].length)
}
}
if l > 0 {
oob = make([]byte, l)
b := oob
if opt.isset(FlagTTL) {
b = ctlOpts[ctlTTL].marshal(b, nil)
}
if ctlOpts[ctlPacketInfo].name > 0 {
if opt.isset(FlagSrc | FlagDst | FlagInterface) {
b = ctlOpts[ctlPacketInfo].marshal(b, nil)
}
} else {
if opt.isset(FlagDst) {
b = ctlOpts[ctlDst].marshal(b, nil)
}
if opt.isset(FlagInterface) {
b = ctlOpts[ctlInterface].marshal(b, nil)
}
}
}
opt.RUnlock()
return
}
func newControlMessage(opt *rawOpt) (oob []byte) {
opt.Lock()
defer opt.Unlock()
l, off := 0, 0
if opt.isset(FlagTrafficClass) {
l += syscall.CmsgSpace(4)
}
if opt.isset(FlagHopLimit) {
l += syscall.CmsgSpace(4)
}
if opt.isset(pktinfo) {
l += syscall.CmsgSpace(syscall.SizeofInet6Pktinfo)
}
if opt.isset(FlagPathMTU) {
l += syscall.CmsgSpace(syscall.SizeofIPv6MTUInfo)
}
if l > 0 {
oob = make([]byte, l)
if opt.isset(FlagTrafficClass) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = syscall.IPV6_RECVTCLASS
m.SetLen(syscall.CmsgLen(4))
off += syscall.CmsgSpace(4)
}
if opt.isset(FlagHopLimit) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = syscall.IPV6_RECVHOPLIMIT
m.SetLen(syscall.CmsgLen(4))
off += syscall.CmsgSpace(4)
}
if opt.isset(pktinfo) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = syscall.IPV6_RECVPKTINFO
m.SetLen(syscall.CmsgLen(syscall.SizeofInet6Pktinfo))
off += syscall.CmsgSpace(syscall.SizeofInet6Pktinfo)
}
if opt.isset(FlagPathMTU) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = syscall.IPV6_RECVPATHMTU
m.SetLen(syscall.CmsgLen(syscall.SizeofIPv6MTUInfo))
off += syscall.CmsgSpace(syscall.SizeofIPv6MTUInfo)
}
}
return
}
func (conn *UnixConn) receiveUnix(buf []byte) (int, error) {
oob := make([]byte, syscall.CmsgSpace(4))
bufn, oobn, _, _, err := conn.ReadMsgUnix(buf, oob)
if err != nil {
return 0, err
}
fd := extractFd(oob[:oobn])
if fd != -1 {
f := os.NewFile(uintptr(fd), "")
conn.fds = append(conn.fds, f)
}
return bufn, nil
}
func (opt *rawOpt) marshalControlMessage() (oob []byte) {
var off int
oob = make([]byte, opt.oobLen())
if opt.isset(FlagTTL) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIP
m.Type = sysSockoptReceiveTTL
m.SetLen(syscall.CmsgLen(1))
off += syscall.CmsgSpace(1)
}
if supportsPacketInfo {
if opt.isset(FlagSrc | FlagDst | FlagInterface) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIP
m.Type = sysSockoptPacketInfo
m.SetLen(syscall.CmsgLen(sysSizeofPacketInfo))
off += syscall.CmsgSpace(sysSizeofPacketInfo)
}
} else {
if opt.isset(FlagDst) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIP
m.Type = sysSockoptReceiveDst
m.SetLen(syscall.CmsgLen(net.IPv4len))
off += syscall.CmsgSpace(net.IPv4len)
}
if opt.isset(FlagInterface) {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIP
m.Type = sysSockoptReceiveInterface
m.SetLen(syscall.CmsgLen(syscall.SizeofSockaddrDatalink))
off += syscall.CmsgSpace(syscall.SizeofSockaddrDatalink)
}
}
return
}
func marshalPacketInfo(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIP
m.Type = sysIP_PKTINFO
m.SetLen(syscall.CmsgLen(sysSizeofInetPktinfo))
if cm != nil {
pi := (*sysInetPktinfo)(unsafe.Pointer(&b[syscall.CmsgLen(0)]))
if ip := cm.Src.To4(); ip != nil {
copy(pi.Spec_dst[:], ip)
}
if cm.IfIndex > 0 {
pi.setIfindex(cm.IfIndex)
}
}
return b[syscall.CmsgSpace(sysSizeofInetPktinfo):]
}
func marshal2292PacketInfo(b []byte, cm *ControlMessage) []byte {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0]))
m.Level = iana.ProtocolIPv6
m.Type = sysIPV6_2292PKTINFO
m.SetLen(syscall.CmsgLen(sizeofInet6Pktinfo))
if cm != nil {
pi := (*inet6Pktinfo)(unsafe.Pointer(&b[syscall.CmsgLen(0)]))
if ip := cm.Src.To16(); ip != nil && ip.To4() == nil {
copy(pi.Addr[:], ip)
}
if cm.IfIndex > 0 {
pi.setIfindex(cm.IfIndex)
}
}
return b[syscall.CmsgSpace(sizeofInet6Pktinfo):]
}
func marshalControlMessage(cm *ControlMessage) (oob []byte) {
if cm == nil {
return
}
l, off := 0, 0
if cm.HopLimit > 0 {
l += syscall.CmsgSpace(4)
}
pion := false
if cm.Src.To4() == nil && cm.Src.To16() != nil || cm.IfIndex != 0 {
pion = true
l += syscall.CmsgSpace(sysSizeofPacketInfo)
}
if len(cm.NextHop) == net.IPv6len {
l += syscall.CmsgSpace(syscall.SizeofSockaddrInet6)
}
if l > 0 {
oob = make([]byte, l)
if cm.HopLimit > 0 {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = sysSockopt2292HopLimit
m.SetLen(syscall.CmsgLen(4))
data := oob[off+syscall.CmsgLen(0):]
*(*byte)(unsafe.Pointer(&data[:1][0])) = byte(cm.HopLimit)
off += syscall.CmsgSpace(4)
}
if pion {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = sysSockopt2292PacketInfo
m.SetLen(syscall.CmsgLen(sysSizeofPacketInfo))
pi := (*sysPacketInfo)(unsafe.Pointer(&oob[off+syscall.CmsgLen(0)]))
if ip := cm.Src.To16(); ip != nil && ip.To4() == nil {
copy(pi.IP[:], ip)
}
if cm.IfIndex != 0 {
pi.IfIndex = uint32(cm.IfIndex)
}
off += syscall.CmsgSpace(sysSizeofPacketInfo)
}
if len(cm.NextHop) == net.IPv6len {
m := (*syscall.Cmsghdr)(unsafe.Pointer(&oob[off]))
m.Level = ianaProtocolIPv6
m.Type = sysSockopt2292NextHop
m.SetLen(syscall.CmsgLen(syscall.SizeofSockaddrInet6))
sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(&oob[off+syscall.CmsgLen(0)]))
sa.Len = syscall.SizeofSockaddrInet6
sa.Family = syscall.AF_INET6
copy(sa.Addr[:], cm.NextHop)
off += syscall.CmsgSpace(syscall.SizeofSockaddrInet6)
}
}
return
}
func marshalControlMessage(cm *ControlMessage) (oob []byte) {
if cm == nil {
return nil
}
var l int
pktinfo := false
if ctlOpts[ctlPacketInfo].name > 0 && (cm.Src.To4() != nil || cm.IfIndex > 0) {
pktinfo = true
l += syscall.CmsgSpace(ctlOpts[ctlPacketInfo].length)
}
if l > 0 {
oob = make([]byte, l)
b := oob
if pktinfo {
b = ctlOpts[ctlPacketInfo].marshal(b, cm)
}
}
return
}
// Get receives file descriptors from a Unix domain socket.
//
// Num specifies the expected number of file descriptors in one message.
// Internal files' names to be assigned are specified via optional filenames
// argument.
//
// You need to close all files in the returned slice. The slice can be
// non-empty even if this function returns an error.
//
// Use net.FileConn() if you're receiving a network connection.
func Get(via *net.UnixConn, num int, filenames []string) ([]*os.File, error) {
if num < 1 {
return nil, nil
}
// get the underlying socket
viaf, err := via.File()
if err != nil {
return nil, err
}
socket := int(viaf.Fd())
defer viaf.Close()
// recvmsg
buf := make([]byte, syscall.CmsgSpace(num*4))
_, _, _, _, err = syscall.Recvmsg(socket, nil, buf, 0)
if err != nil {
return nil, err
}
// parse control msgs
var msgs []syscall.SocketControlMessage
msgs, err = syscall.ParseSocketControlMessage(buf)
// convert fds to files
res := make([]*os.File, 0, len(msgs))
for i := 0; i < len(msgs) && err == nil; i++ {
var fds []int
fds, err = syscall.ParseUnixRights(&msgs[i])
for fi, fd := range fds {
var filename string
if fi < len(filenames) {
filename = filenames[fi]
}
res = append(res, os.NewFile(uintptr(fd), filename))
}
}
return res, err
}
func marshalControlMessage(cm *ControlMessage) (oob []byte) {
if cm == nil {
return nil
}
var l int
if ctlOpts[ctlPacketInfo].name > 0 {
if cm.Src.To4() != nil || cm.IfIndex != 0 {
l += syscall.CmsgSpace(ctlOpts[ctlPacketInfo].length)
}
}
if l > 0 {
oob = make([]byte, l)
b := oob
if ctlOpts[ctlPacketInfo].name > 0 {
if cm.Src.To4() != nil || cm.IfIndex != 0 {
b = ctlOpts[ctlPacketInfo].marshal(b, cm)
}
}
}
return
}