diff --git a/unum/vendor/golang.org/x/net/ipv4/sys_linux.go b/unum/vendor/golang.org/x/net/ipv4/sys_linux.go
new file mode 100644
index 0000000..60defe1
--- /dev/null
+++ b/unum/vendor/golang.org/x/net/ipv4/sys_linux.go
@@ -0,0 +1,59 @@
+// 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"
+
+	"golang.org/x/net/internal/iana"
+	"golang.org/x/net/internal/socket"
+)
+
+var (
+	ctlOpts = [ctlMax]ctlOpt{
+		ctlTTL:        {sysIP_TTL, 1, marshalTTL, parseTTL},
+		ctlPacketInfo: {sysIP_PKTINFO, sizeofInetPktinfo, marshalPacketInfo, parsePacketInfo},
+	}
+
+	sockOpts = map[int]*sockOpt{
+		ssoTOS:                {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_TOS, Len: 4}},
+		ssoTTL:                {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_TTL, Len: 4}},
+		ssoMulticastTTL:       {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_MULTICAST_TTL, Len: 4}},
+		ssoMulticastInterface: {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_MULTICAST_IF, Len: sizeofIPMreqn}, typ: ssoTypeIPMreqn},
+		ssoMulticastLoopback:  {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_MULTICAST_LOOP, Len: 4}},
+		ssoReceiveTTL:         {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_RECVTTL, Len: 4}},
+		ssoPacketInfo:         {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_PKTINFO, Len: 4}},
+		ssoHeaderPrepend:      {Option: socket.Option{Level: iana.ProtocolIP, Name: sysIP_HDRINCL, Len: 4}},
+		ssoICMPFilter:         {Option: socket.Option{Level: iana.ProtocolReserved, Name: sysICMP_FILTER, Len: sizeofICMPFilter}},
+		ssoJoinGroup:          {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_JOIN_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq},
+		ssoLeaveGroup:         {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_LEAVE_GROUP, Len: sizeofGroupReq}, typ: ssoTypeGroupReq},
+		ssoJoinSourceGroup:    {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_JOIN_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
+		ssoLeaveSourceGroup:   {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_LEAVE_SOURCE_GROUP, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
+		ssoBlockSourceGroup:   {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_BLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
+		ssoUnblockSourceGroup: {Option: socket.Option{Level: iana.ProtocolIP, Name: sysMCAST_UNBLOCK_SOURCE, Len: sizeofGroupSourceReq}, typ: ssoTypeGroupSourceReq},
+		ssoAttachFilter:       {Option: socket.Option{Level: sysSOL_SOCKET, Name: sysSO_ATTACH_FILTER, Len: sizeofSockFprog}},
+	}
+)
+
+func (pi *inetPktinfo) setIfindex(i int) {
+	pi.Ifindex = int32(i)
+}
+
+func (gr *groupReq) setGroup(grp net.IP) {
+	sa := (*sockaddrInet)(unsafe.Pointer(&gr.Group))
+	sa.Family = syscall.AF_INET
+	copy(sa.Addr[:], grp)
+}
+
+func (gsr *groupSourceReq) setSourceGroup(grp, src net.IP) {
+	sa := (*sockaddrInet)(unsafe.Pointer(&gsr.Group))
+	sa.Family = syscall.AF_INET
+	copy(sa.Addr[:], grp)
+	sa = (*sockaddrInet)(unsafe.Pointer(&gsr.Source))
+	sa.Family = syscall.AF_INET
+	copy(sa.Addr[:], src)
+}