diff --git a/ipv4/batch.go b/ipv4/batch.go
new file mode 100644
index 00000000..b4454992
--- /dev/null
+++ b/ipv4/batch.go
@@ -0,0 +1,191 @@
+// Copyright 2017 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.
+
+// +build go1.9
+
+package ipv4
+
+import (
+	"net"
+	"runtime"
+	"syscall"
+
+	"golang.org/x/net/internal/socket"
+)
+
+// BUG(mikio): On Windows, the ReadBatch and WriteBatch methods of
+// PacketConn are not implemented.
+
+// BUG(mikio): On Windows, the ReadBatch and WriteBatch methods of
+// RawConn are not implemented.
+
+// A Message represents an IO message.
+//
+//	type Message struct {
+//		Buffers [][]byte
+//		OOB     []byte
+//		Addr    net.Addr
+//		N       int
+//		NN      int
+//		Flags   int
+//	}
+//
+// The Buffers fields represents a list of contiguous buffers, which
+// can be used for vectored IO, for example, putting a header and a
+// payload in each slice.
+// When writing, the Buffers field must contain at least one byte to
+// write.
+// When reading, the Buffers field will always contain a byte to read.
+//
+// The OOB field contains protocol-specific control or miscellaneous
+// ancillary data known as out-of-band data.
+// It can be nil when not required.
+//
+// The Addr field specifies a destination address when writing.
+// It can be nil when the underlying protocol of the endpoint uses
+// connection-oriented communication.
+// After a successful read, it may contain the source address on the
+// received packet.
+//
+// The N field indicates the number of bytes read or written from/to
+// Buffers.
+//
+// The NN field indicates the number of bytes read or written from/to
+// OOB.
+//
+// The Flags field contains protocol-specific information on the
+// received message.
+type Message = socket.Message
+
+// ReadBatch reads a batch of messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_PEEK.
+//
+// On a successful read it returns the number of messages received, up
+// to len(ms).
+//
+// On Linux, a batch read will be optimized.
+// On other platforms, this method will read only a single message.
+//
+// Unlike the ReadFrom method, it doesn't strip the IPv4 header
+// followed by option headers from the received IPv4 datagram when the
+// underlying transport is net.IPConn. Each Buffers field of Message
+// must be large enough to accommodate an IPv4 header and option
+// headers.
+func (c *payloadHandler) ReadBatch(ms []Message, flags int) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	switch runtime.GOOS {
+	case "linux":
+		n, err := c.RecvMsgs([]socket.Message(ms), flags)
+		if err != nil {
+			err = &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+		}
+		return n, err
+	default:
+		n := 1
+		err := c.RecvMsg(&ms[0], flags)
+		if err != nil {
+			n = 0
+			err = &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+		}
+		return n, err
+	}
+}
+
+// WriteBatch writes a batch of messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_DONTROUTE.
+//
+// It returns the number of messages written on a successful write.
+//
+// On Linux, a batch write will be optimized.
+// On other platforms, this method will write only a single message.
+func (c *payloadHandler) WriteBatch(ms []Message, flags int) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	switch runtime.GOOS {
+	case "linux":
+		n, err := c.SendMsgs([]socket.Message(ms), flags)
+		if err != nil {
+			err = &net.OpError{Op: "write", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+		}
+		return n, err
+	default:
+		n := 1
+		err := c.SendMsg(&ms[0], flags)
+		if err != nil {
+			n = 0
+			err = &net.OpError{Op: "write", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+		}
+		return n, err
+	}
+}
+
+// ReadBatch reads a batch of messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_PEEK.
+//
+// On a successful read it returns the number of messages received, up
+// to len(ms).
+//
+// On Linux, a batch read will be optimized.
+// On other platforms, this method will read only a single message.
+func (c *packetHandler) ReadBatch(ms []Message, flags int) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	switch runtime.GOOS {
+	case "linux":
+		n, err := c.RecvMsgs([]socket.Message(ms), flags)
+		if err != nil {
+			err = &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+		}
+		return n, err
+	default:
+		n := 1
+		err := c.RecvMsg(&ms[0], flags)
+		if err != nil {
+			n = 0
+			err = &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+		}
+		return n, err
+	}
+}
+
+// WriteBatch writes a batch of messages.
+//
+// The provided flags is a set of platform-dependent flags, such as
+// syscall.MSG_DONTROUTE.
+//
+// It returns the number of messages written on a successful write.
+//
+// On Linux, a batch write will be optimized.
+// On other platforms, this method will write only a single message.
+func (c *packetHandler) WriteBatch(ms []Message, flags int) (int, error) {
+	if !c.ok() {
+		return 0, syscall.EINVAL
+	}
+	switch runtime.GOOS {
+	case "linux":
+		n, err := c.SendMsgs([]socket.Message(ms), flags)
+		if err != nil {
+			err = &net.OpError{Op: "write", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+		}
+		return n, err
+	default:
+		n := 1
+		err := c.SendMsg(&ms[0], flags)
+		if err != nil {
+			n = 0
+			err = &net.OpError{Op: "write", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+		}
+		return n, err
+	}
+}
diff --git a/ipv4/control.go b/ipv4/control.go
index da4da2dd..fc99327a 100644
--- a/ipv4/control.go
+++ b/ipv4/control.go
@@ -8,6 +8,9 @@ import (
 	"fmt"
 	"net"
 	"sync"
+
+	"golang.org/x/net/internal/iana"
+	"golang.org/x/net/internal/socket"
 )
 
 type rawOpt struct {
@@ -51,6 +54,77 @@ func (cm *ControlMessage) String() string {
 	return fmt.Sprintf("ttl=%d src=%v dst=%v ifindex=%d", cm.TTL, cm.Src, cm.Dst, cm.IfIndex)
 }
 
+// Marshal returns the binary encoding of cm.
+func (cm *ControlMessage) Marshal() []byte {
+	if cm == nil {
+		return nil
+	}
+	var m socket.ControlMessage
+	if ctlOpts[ctlPacketInfo].name > 0 && (cm.Src.To4() != nil || cm.IfIndex > 0) {
+		m = socket.NewControlMessage([]int{ctlOpts[ctlPacketInfo].length})
+	}
+	if len(m) > 0 {
+		ctlOpts[ctlPacketInfo].marshal(m, cm)
+	}
+	return m
+}
+
+// Parse parses b as a control message and stores the result in cm.
+func (cm *ControlMessage) Parse(b []byte) error {
+	ms, err := socket.ControlMessage(b).Parse()
+	if err != nil {
+		return err
+	}
+	for _, m := range ms {
+		lvl, typ, l, err := m.ParseHeader()
+		if err != nil {
+			return err
+		}
+		if lvl != iana.ProtocolIP {
+			continue
+		}
+		switch typ {
+		case ctlOpts[ctlTTL].name:
+			ctlOpts[ctlTTL].parse(cm, m.Data(l))
+		case ctlOpts[ctlDst].name:
+			ctlOpts[ctlDst].parse(cm, m.Data(l))
+		case ctlOpts[ctlInterface].name:
+			ctlOpts[ctlInterface].parse(cm, m.Data(l))
+		case ctlOpts[ctlPacketInfo].name:
+			ctlOpts[ctlPacketInfo].parse(cm, m.Data(l))
+		}
+	}
+	return nil
+}
+
+// NewControlMessage returns a new control message.
+//
+// The returned message is large enough for options specified by cf.
+func NewControlMessage(cf ControlFlags) []byte {
+	opt := rawOpt{cflags: cf}
+	var l int
+	if opt.isset(FlagTTL) && ctlOpts[ctlTTL].name > 0 {
+		l += socket.ControlMessageSpace(ctlOpts[ctlTTL].length)
+	}
+	if ctlOpts[ctlPacketInfo].name > 0 {
+		if opt.isset(FlagSrc | FlagDst | FlagInterface) {
+			l += socket.ControlMessageSpace(ctlOpts[ctlPacketInfo].length)
+		}
+	} else {
+		if opt.isset(FlagDst) && ctlOpts[ctlDst].name > 0 {
+			l += socket.ControlMessageSpace(ctlOpts[ctlDst].length)
+		}
+		if opt.isset(FlagInterface) && ctlOpts[ctlInterface].name > 0 {
+			l += socket.ControlMessageSpace(ctlOpts[ctlInterface].length)
+		}
+	}
+	var b []byte
+	if l > 0 {
+		b = make([]byte, l)
+	}
+	return b
+}
+
 // Ancillary data socket options
 const (
 	ctlTTL        = iota // header field
diff --git a/ipv4/control_bsd.go b/ipv4/control_bsd.go
index 3f27f994..77e7ad5b 100644
--- a/ipv4/control_bsd.go
+++ b/ipv4/control_bsd.go
@@ -12,26 +12,26 @@ import (
 	"unsafe"
 
 	"golang.org/x/net/internal/iana"
+	"golang.org/x/net/internal/socket"
 )
 
 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):]
+	m := socket.ControlMessage(b)
+	m.MarshalHeader(iana.ProtocolIP, sysIP_RECVDSTADDR, net.IPv4len)
+	return m.Next(net.IPv4len)
 }
 
 func parseDst(cm *ControlMessage, b []byte) {
-	cm.Dst = b[:net.IPv4len]
+	if len(cm.Dst) < net.IPv4len {
+		cm.Dst = make(net.IP, net.IPv4len)
+	}
+	copy(cm.Dst, b[: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):]
+	m := socket.ControlMessage(b)
+	m.MarshalHeader(iana.ProtocolIP, sysIP_RECVIF, syscall.SizeofSockaddrDatalink)
+	return m.Next(syscall.SizeofSockaddrDatalink)
 }
 
 func parseInterface(cm *ControlMessage, b []byte) {
diff --git a/ipv4/control_pktinfo.go b/ipv4/control_pktinfo.go
index 9ed97734..425338f3 100644
--- a/ipv4/control_pktinfo.go
+++ b/ipv4/control_pktinfo.go
@@ -7,19 +7,18 @@
 package ipv4
 
 import (
-	"syscall"
+	"net"
 	"unsafe"
 
 	"golang.org/x/net/internal/iana"
+	"golang.org/x/net/internal/socket"
 )
 
 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(sizeofInetPktinfo))
+	m := socket.ControlMessage(b)
+	m.MarshalHeader(iana.ProtocolIP, sysIP_PKTINFO, sizeofInetPktinfo)
 	if cm != nil {
-		pi := (*inetPktinfo)(unsafe.Pointer(&b[syscall.CmsgLen(0)]))
+		pi := (*inetPktinfo)(unsafe.Pointer(&m.Data(sizeofInetPktinfo)[0]))
 		if ip := cm.Src.To4(); ip != nil {
 			copy(pi.Spec_dst[:], ip)
 		}
@@ -27,11 +26,14 @@ func marshalPacketInfo(b []byte, cm *ControlMessage) []byte {
 			pi.setIfindex(cm.IfIndex)
 		}
 	}
-	return b[syscall.CmsgSpace(sizeofInetPktinfo):]
+	return m.Next(sizeofInetPktinfo)
 }
 
 func parsePacketInfo(cm *ControlMessage, b []byte) {
 	pi := (*inetPktinfo)(unsafe.Pointer(&b[0]))
 	cm.IfIndex = int(pi.Ifindex)
-	cm.Dst = pi.Addr[:]
+	if len(cm.Dst) < net.IPv4len {
+		cm.Dst = make(net.IP, net.IPv4len)
+	}
+	copy(cm.Dst, pi.Addr[:])
 }
diff --git a/ipv4/control_stub.go b/ipv4/control_stub.go
index de9b1a09..5a2f7d8d 100644
--- a/ipv4/control_stub.go
+++ b/ipv4/control_stub.go
@@ -11,15 +11,3 @@ import "golang.org/x/net/internal/socket"
 func setControlMessage(c *socket.Conn, opt *rawOpt, cf ControlFlags, on bool) error {
 	return errOpNoSupport
 }
-
-func newControlMessage(opt *rawOpt) []byte {
-	return nil
-}
-
-func parseControlMessage(b []byte) (*ControlMessage, error) {
-	return nil, errOpNoSupport
-}
-
-func marshalControlMessage(cm *ControlMessage) []byte {
-	return nil
-}
diff --git a/ipv4/control_unix.go b/ipv4/control_unix.go
index 91115201..e1ae8167 100644
--- a/ipv4/control_unix.go
+++ b/ipv4/control_unix.go
@@ -7,8 +7,6 @@
 package ipv4
 
 import (
-	"os"
-	"syscall"
 	"unsafe"
 
 	"golang.org/x/net/internal/iana"
@@ -64,84 +62,10 @@ func setControlMessage(c *socket.Conn, opt *rawOpt, cf ControlFlags, on bool) er
 	return nil
 }
 
-func newControlMessage(opt *rawOpt) (oob []byte) {
-	opt.RLock()
-	var l int
-	if opt.isset(FlagTTL) && ctlOpts[ctlTTL].name > 0 {
-		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) && ctlOpts[ctlDst].name > 0 {
-			l += syscall.CmsgSpace(ctlOpts[ctlDst].length)
-		}
-		if opt.isset(FlagInterface) && ctlOpts[ctlInterface].name > 0 {
-			l += syscall.CmsgSpace(ctlOpts[ctlInterface].length)
-		}
-	}
-	if l > 0 {
-		oob = make([]byte, l)
-	}
-	opt.RUnlock()
-	return
-}
-
-func parseControlMessage(b []byte) (*ControlMessage, error) {
-	if len(b) == 0 {
-		return nil, nil
-	}
-	cmsgs, err := syscall.ParseSocketControlMessage(b)
-	if err != nil {
-		return nil, os.NewSyscallError("parse socket control message", err)
-	}
-	cm := &ControlMessage{}
-	for _, m := range cmsgs {
-		if m.Header.Level != iana.ProtocolIP {
-			continue
-		}
-		switch int(m.Header.Type) {
-		case ctlOpts[ctlTTL].name:
-			ctlOpts[ctlTTL].parse(cm, m.Data[:])
-		case ctlOpts[ctlDst].name:
-			ctlOpts[ctlDst].parse(cm, m.Data[:])
-		case ctlOpts[ctlInterface].name:
-			ctlOpts[ctlInterface].parse(cm, m.Data[:])
-		case ctlOpts[ctlPacketInfo].name:
-			ctlOpts[ctlPacketInfo].parse(cm, m.Data[:])
-		}
-	}
-	return cm, nil
-}
-
-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
-}
-
 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):]
+	m := socket.ControlMessage(b)
+	m.MarshalHeader(iana.ProtocolIP, sysIP_RECVTTL, 1)
+	return m.Next(1)
 }
 
 func parseTTL(cm *ControlMessage, b []byte) {
diff --git a/ipv4/control_windows.go b/ipv4/control_windows.go
index 5560fcf2..ce55c664 100644
--- a/ipv4/control_windows.go
+++ b/ipv4/control_windows.go
@@ -14,18 +14,3 @@ func setControlMessage(c *socket.Conn, opt *rawOpt, cf ControlFlags, on bool) er
 	// TODO(mikio): implement this
 	return syscall.EWINDOWS
 }
-
-func newControlMessage(opt *rawOpt) []byte {
-	// TODO(mikio): implement this
-	return nil
-}
-
-func parseControlMessage(b []byte) (*ControlMessage, error) {
-	// TODO(mikio): implement this
-	return nil, syscall.EWINDOWS
-}
-
-func marshalControlMessage(cm *ControlMessage) []byte {
-	// TODO(mikio): implement this
-	return nil
-}
diff --git a/ipv4/endpoint.go b/ipv4/endpoint.go
index f173ed40..2ab87736 100644
--- a/ipv4/endpoint.go
+++ b/ipv4/endpoint.go
@@ -105,12 +105,7 @@ func NewPacketConn(c net.PacketConn) *PacketConn {
 	p := &PacketConn{
 		genericOpt:     genericOpt{Conn: cc},
 		dgramOpt:       dgramOpt{Conn: cc},
-		payloadHandler: payloadHandler{PacketConn: c},
-	}
-	if _, ok := c.(*net.IPConn); ok {
-		if so, ok := sockOpts[ssoStripHeader]; ok {
-			so.SetInt(p.dgramOpt.Conn, boolint(true))
-		}
+		payloadHandler: payloadHandler{PacketConn: c, Conn: cc},
 	}
 	return p
 }
@@ -140,7 +135,7 @@ func (c *RawConn) SetDeadline(t time.Time) error {
 	if !c.packetHandler.ok() {
 		return syscall.EINVAL
 	}
-	return c.packetHandler.c.SetDeadline(t)
+	return c.packetHandler.IPConn.SetDeadline(t)
 }
 
 // SetReadDeadline sets the read deadline associated with the
@@ -149,7 +144,7 @@ func (c *RawConn) SetReadDeadline(t time.Time) error {
 	if !c.packetHandler.ok() {
 		return syscall.EINVAL
 	}
-	return c.packetHandler.c.SetReadDeadline(t)
+	return c.packetHandler.IPConn.SetReadDeadline(t)
 }
 
 // SetWriteDeadline sets the write deadline associated with the
@@ -158,7 +153,7 @@ func (c *RawConn) SetWriteDeadline(t time.Time) error {
 	if !c.packetHandler.ok() {
 		return syscall.EINVAL
 	}
-	return c.packetHandler.c.SetWriteDeadline(t)
+	return c.packetHandler.IPConn.SetWriteDeadline(t)
 }
 
 // Close closes the endpoint.
@@ -166,7 +161,7 @@ func (c *RawConn) Close() error {
 	if !c.packetHandler.ok() {
 		return syscall.EINVAL
 	}
-	return c.packetHandler.c.Close()
+	return c.packetHandler.IPConn.Close()
 }
 
 // NewRawConn returns a new RawConn using c as its underlying
@@ -179,7 +174,7 @@ func NewRawConn(c net.PacketConn) (*RawConn, error) {
 	r := &RawConn{
 		genericOpt:    genericOpt{Conn: cc},
 		dgramOpt:      dgramOpt{Conn: cc},
-		packetHandler: packetHandler{c: c.(*net.IPConn)},
+		packetHandler: packetHandler{IPConn: c.(*net.IPConn), Conn: cc},
 	}
 	so, ok := sockOpts[ssoHeaderPrepend]
 	if !ok {
diff --git a/ipv4/header.go b/ipv4/header.go
index 6480597f..8bb0f0f4 100644
--- a/ipv4/header.go
+++ b/ipv4/header.go
@@ -51,7 +51,7 @@ func (h *Header) String() string {
 	return fmt.Sprintf("ver=%d hdrlen=%d tos=%#x totallen=%d id=%#x flags=%#x fragoff=%#x ttl=%d proto=%d cksum=%#x src=%v dst=%v", h.Version, h.Len, h.TOS, h.TotalLen, h.ID, h.Flags, h.FragOff, h.TTL, h.Protocol, h.Checksum, h.Src, h.Dst)
 }
 
-// Marshal returns the binary encoding of the IPv4 header h.
+// Marshal returns the binary encoding of h.
 func (h *Header) Marshal() ([]byte, error) {
 	if h == nil {
 		return nil, syscall.EINVAL
@@ -98,26 +98,24 @@ func (h *Header) Marshal() ([]byte, error) {
 	return b, nil
 }
 
-// ParseHeader parses b as an IPv4 header.
-func ParseHeader(b []byte) (*Header, error) {
-	if len(b) < HeaderLen {
-		return nil, errHeaderTooShort
+// Parse parses b as an IPv4 header and sotres the result in h.
+func (h *Header) Parse(b []byte) error {
+	if h == nil || len(b) < HeaderLen {
+		return errHeaderTooShort
 	}
 	hdrlen := int(b[0]&0x0f) << 2
 	if hdrlen > len(b) {
-		return nil, errBufferTooShort
-	}
-	h := &Header{
-		Version:  int(b[0] >> 4),
-		Len:      hdrlen,
-		TOS:      int(b[1]),
-		ID:       int(binary.BigEndian.Uint16(b[4:6])),
-		TTL:      int(b[8]),
-		Protocol: int(b[9]),
-		Checksum: int(binary.BigEndian.Uint16(b[10:12])),
-		Src:      net.IPv4(b[12], b[13], b[14], b[15]),
-		Dst:      net.IPv4(b[16], b[17], b[18], b[19]),
+		return errBufferTooShort
 	}
+	h.Version = int(b[0] >> 4)
+	h.Len = hdrlen
+	h.TOS = int(b[1])
+	h.ID = int(binary.BigEndian.Uint16(b[4:6]))
+	h.TTL = int(b[8])
+	h.Protocol = int(b[9])
+	h.Checksum = int(binary.BigEndian.Uint16(b[10:12]))
+	h.Src = net.IPv4(b[12], b[13], b[14], b[15])
+	h.Dst = net.IPv4(b[16], b[17], b[18], b[19])
 	switch runtime.GOOS {
 	case "darwin", "dragonfly", "netbsd":
 		h.TotalLen = int(socket.NativeEndian.Uint16(b[2:4])) + hdrlen
@@ -139,9 +137,23 @@ func ParseHeader(b []byte) (*Header, error) {
 	}
 	h.Flags = HeaderFlags(h.FragOff&0xe000) >> 13
 	h.FragOff = h.FragOff & 0x1fff
-	if hdrlen-HeaderLen > 0 {
-		h.Options = make([]byte, hdrlen-HeaderLen)
-		copy(h.Options, b[HeaderLen:])
+	optlen := hdrlen - HeaderLen
+	if optlen > 0 && len(b) >= hdrlen {
+		if cap(h.Options) < optlen {
+			h.Options = make([]byte, optlen)
+		} else {
+			h.Options = h.Options[:optlen]
+		}
+		copy(h.Options, b[HeaderLen:hdrlen])
+	}
+	return nil
+}
+
+// ParseHeader parses b as an IPv4 header.
+func ParseHeader(b []byte) (*Header, error) {
+	h := new(Header)
+	if err := h.Parse(b); err != nil {
+		return nil, err
 	}
 	return h, nil
 }
diff --git a/ipv4/header_test.go b/ipv4/header_test.go
index 8dd6fc60..a246aeea 100644
--- a/ipv4/header_test.go
+++ b/ipv4/header_test.go
@@ -17,138 +17,212 @@ import (
 )
 
 type headerTest struct {
-	wireHeaderFromKernel          [HeaderLen]byte
-	wireHeaderToKernel            [HeaderLen]byte
-	wireHeaderFromTradBSDKernel   [HeaderLen]byte
-	wireHeaderToTradBSDKernel     [HeaderLen]byte
-	wireHeaderFromFreeBSD10Kernel [HeaderLen]byte
-	wireHeaderToFreeBSD10Kernel   [HeaderLen]byte
+	wireHeaderFromKernel          []byte
+	wireHeaderToKernel            []byte
+	wireHeaderFromTradBSDKernel   []byte
+	wireHeaderToTradBSDKernel     []byte
+	wireHeaderFromFreeBSD10Kernel []byte
+	wireHeaderToFreeBSD10Kernel   []byte
 	*Header
 }
 
-var headerLittleEndianTest = headerTest{
+var headerLittleEndianTests = []headerTest{
 	// TODO(mikio): Add platform dependent wire header formats when
 	// we support new platforms.
-	wireHeaderFromKernel: [HeaderLen]byte{
-		0x45, 0x01, 0xbe, 0xef,
-		0xca, 0xfe, 0x45, 0xdc,
-		0xff, 0x01, 0xde, 0xad,
-		172, 16, 254, 254,
-		192, 168, 0, 1,
+	{
+		wireHeaderFromKernel: []byte{
+			0x45, 0x01, 0xbe, 0xef,
+			0xca, 0xfe, 0x45, 0xdc,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+		},
+		wireHeaderToKernel: []byte{
+			0x45, 0x01, 0xbe, 0xef,
+			0xca, 0xfe, 0x45, 0xdc,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+		},
+		wireHeaderFromTradBSDKernel: []byte{
+			0x45, 0x01, 0xdb, 0xbe,
+			0xca, 0xfe, 0xdc, 0x45,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+		},
+		wireHeaderToTradBSDKernel: []byte{
+			0x45, 0x01, 0xef, 0xbe,
+			0xca, 0xfe, 0xdc, 0x45,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+		},
+		wireHeaderFromFreeBSD10Kernel: []byte{
+			0x45, 0x01, 0xef, 0xbe,
+			0xca, 0xfe, 0xdc, 0x45,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+		},
+		wireHeaderToFreeBSD10Kernel: []byte{
+			0x45, 0x01, 0xef, 0xbe,
+			0xca, 0xfe, 0xdc, 0x45,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+		},
+		Header: &Header{
+			Version:  Version,
+			Len:      HeaderLen,
+			TOS:      1,
+			TotalLen: 0xbeef,
+			ID:       0xcafe,
+			Flags:    DontFragment,
+			FragOff:  1500,
+			TTL:      255,
+			Protocol: 1,
+			Checksum: 0xdead,
+			Src:      net.IPv4(172, 16, 254, 254),
+			Dst:      net.IPv4(192, 168, 0, 1),
+		},
 	},
-	wireHeaderToKernel: [HeaderLen]byte{
-		0x45, 0x01, 0xbe, 0xef,
-		0xca, 0xfe, 0x45, 0xdc,
-		0xff, 0x01, 0xde, 0xad,
-		172, 16, 254, 254,
-		192, 168, 0, 1,
-	},
-	wireHeaderFromTradBSDKernel: [HeaderLen]byte{
-		0x45, 0x01, 0xdb, 0xbe,
-		0xca, 0xfe, 0xdc, 0x45,
-		0xff, 0x01, 0xde, 0xad,
-		172, 16, 254, 254,
-		192, 168, 0, 1,
-	},
-	wireHeaderToTradBSDKernel: [HeaderLen]byte{
-		0x45, 0x01, 0xef, 0xbe,
-		0xca, 0xfe, 0xdc, 0x45,
-		0xff, 0x01, 0xde, 0xad,
-		172, 16, 254, 254,
-		192, 168, 0, 1,
-	},
-	wireHeaderFromFreeBSD10Kernel: [HeaderLen]byte{
-		0x45, 0x01, 0xef, 0xbe,
-		0xca, 0xfe, 0xdc, 0x45,
-		0xff, 0x01, 0xde, 0xad,
-		172, 16, 254, 254,
-		192, 168, 0, 1,
-	},
-	wireHeaderToFreeBSD10Kernel: [HeaderLen]byte{
-		0x45, 0x01, 0xef, 0xbe,
-		0xca, 0xfe, 0xdc, 0x45,
-		0xff, 0x01, 0xde, 0xad,
-		172, 16, 254, 254,
-		192, 168, 0, 1,
-	},
-	Header: &Header{
-		Version:  Version,
-		Len:      HeaderLen,
-		TOS:      1,
-		TotalLen: 0xbeef,
-		ID:       0xcafe,
-		Flags:    DontFragment,
-		FragOff:  1500,
-		TTL:      255,
-		Protocol: 1,
-		Checksum: 0xdead,
-		Src:      net.IPv4(172, 16, 254, 254),
-		Dst:      net.IPv4(192, 168, 0, 1),
+
+	// with option headers
+	{
+		wireHeaderFromKernel: []byte{
+			0x46, 0x01, 0xbe, 0xf3,
+			0xca, 0xfe, 0x45, 0xdc,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+			0xff, 0xfe, 0xfe, 0xff,
+		},
+		wireHeaderToKernel: []byte{
+			0x46, 0x01, 0xbe, 0xf3,
+			0xca, 0xfe, 0x45, 0xdc,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+			0xff, 0xfe, 0xfe, 0xff,
+		},
+		wireHeaderFromTradBSDKernel: []byte{
+			0x46, 0x01, 0xdb, 0xbe,
+			0xca, 0xfe, 0xdc, 0x45,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+			0xff, 0xfe, 0xfe, 0xff,
+		},
+		wireHeaderToTradBSDKernel: []byte{
+			0x46, 0x01, 0xf3, 0xbe,
+			0xca, 0xfe, 0xdc, 0x45,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+			0xff, 0xfe, 0xfe, 0xff,
+		},
+		wireHeaderFromFreeBSD10Kernel: []byte{
+			0x46, 0x01, 0xf3, 0xbe,
+			0xca, 0xfe, 0xdc, 0x45,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+			0xff, 0xfe, 0xfe, 0xff,
+		},
+		wireHeaderToFreeBSD10Kernel: []byte{
+			0x46, 0x01, 0xf3, 0xbe,
+			0xca, 0xfe, 0xdc, 0x45,
+			0xff, 0x01, 0xde, 0xad,
+			172, 16, 254, 254,
+			192, 168, 0, 1,
+			0xff, 0xfe, 0xfe, 0xff,
+		},
+		Header: &Header{
+			Version:  Version,
+			Len:      HeaderLen + 4,
+			TOS:      1,
+			TotalLen: 0xbef3,
+			ID:       0xcafe,
+			Flags:    DontFragment,
+			FragOff:  1500,
+			TTL:      255,
+			Protocol: 1,
+			Checksum: 0xdead,
+			Src:      net.IPv4(172, 16, 254, 254),
+			Dst:      net.IPv4(192, 168, 0, 1),
+			Options:  []byte{0xff, 0xfe, 0xfe, 0xff},
+		},
 	},
 }
 
 func TestMarshalHeader(t *testing.T) {
-	tt := &headerLittleEndianTest
 	if socket.NativeEndian != binary.LittleEndian {
 		t.Skip("no test for non-little endian machine yet")
 	}
 
-	b, err := tt.Header.Marshal()
-	if err != nil {
-		t.Fatal(err)
-	}
-	var wh []byte
-	switch runtime.GOOS {
-	case "darwin", "dragonfly", "netbsd":
-		wh = tt.wireHeaderToTradBSDKernel[:]
-	case "freebsd":
-		switch {
-		case freebsdVersion < 1000000:
-			wh = tt.wireHeaderToTradBSDKernel[:]
-		case 1000000 <= freebsdVersion && freebsdVersion < 1100000:
-			wh = tt.wireHeaderToFreeBSD10Kernel[:]
-		default:
-			wh = tt.wireHeaderToKernel[:]
+	for _, tt := range headerLittleEndianTests {
+		b, err := tt.Header.Marshal()
+		if err != nil {
+			t.Fatal(err)
+		}
+		var wh []byte
+		switch runtime.GOOS {
+		case "darwin", "dragonfly", "netbsd":
+			wh = tt.wireHeaderToTradBSDKernel
+		case "freebsd":
+			switch {
+			case freebsdVersion < 1000000:
+				wh = tt.wireHeaderToTradBSDKernel
+			case 1000000 <= freebsdVersion && freebsdVersion < 1100000:
+				wh = tt.wireHeaderToFreeBSD10Kernel
+			default:
+				wh = tt.wireHeaderToKernel
+			}
+		default:
+			wh = tt.wireHeaderToKernel
+		}
+		if !bytes.Equal(b, wh) {
+			t.Fatalf("got %#v; want %#v", b, wh)
 		}
-	default:
-		wh = tt.wireHeaderToKernel[:]
-	}
-	if !bytes.Equal(b, wh) {
-		t.Fatalf("got %#v; want %#v", b, wh)
 	}
 }
 
 func TestParseHeader(t *testing.T) {
-	tt := &headerLittleEndianTest
 	if socket.NativeEndian != binary.LittleEndian {
 		t.Skip("no test for big endian machine yet")
 	}
 
-	var wh []byte
-	switch runtime.GOOS {
-	case "darwin", "dragonfly", "netbsd":
-		wh = tt.wireHeaderFromTradBSDKernel[:]
-	case "freebsd":
-		switch {
-		case freebsdVersion < 1000000:
-			wh = tt.wireHeaderFromTradBSDKernel[:]
-		case 1000000 <= freebsdVersion && freebsdVersion < 1100000:
-			wh = tt.wireHeaderFromFreeBSD10Kernel[:]
+	for _, tt := range headerLittleEndianTests {
+		var wh []byte
+		switch runtime.GOOS {
+		case "darwin", "dragonfly", "netbsd":
+			wh = tt.wireHeaderFromTradBSDKernel
+		case "freebsd":
+			switch {
+			case freebsdVersion < 1000000:
+				wh = tt.wireHeaderFromTradBSDKernel
+			case 1000000 <= freebsdVersion && freebsdVersion < 1100000:
+				wh = tt.wireHeaderFromFreeBSD10Kernel
+			default:
+				wh = tt.wireHeaderFromKernel
+			}
 		default:
-			wh = tt.wireHeaderFromKernel[:]
+			wh = tt.wireHeaderFromKernel
+		}
+		h, err := ParseHeader(wh)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := h.Parse(wh); err != nil {
+			t.Fatal(err)
+		}
+		if !reflect.DeepEqual(h, tt.Header) {
+			t.Fatalf("got %#v; want %#v", h, tt.Header)
+		}
+		s := h.String()
+		if strings.Contains(s, ",") {
+			t.Fatalf("should be space-separated values: %s", s)
 		}
-	default:
-		wh = tt.wireHeaderFromKernel[:]
-	}
-	h, err := ParseHeader(wh)
-	if err != nil {
-		t.Fatal(err)
-	}
-	if !reflect.DeepEqual(h, tt.Header) {
-		t.Fatalf("got %#v; want %#v", h, tt.Header)
-	}
-	s := h.String()
-	if strings.Contains(s, ",") {
-		t.Fatalf("should be space-separated values: %s", s)
 	}
 }
diff --git a/ipv4/packet.go b/ipv4/packet.go
index d43723ca..f00f5b05 100644
--- a/ipv4/packet.go
+++ b/ipv4/packet.go
@@ -7,6 +7,8 @@ package ipv4
 import (
 	"net"
 	"syscall"
+
+	"golang.org/x/net/internal/socket"
 )
 
 // BUG(mikio): On Windows, the ReadFrom and WriteTo methods of RawConn
@@ -14,11 +16,12 @@ import (
 
 // A packetHandler represents the IPv4 datagram handler.
 type packetHandler struct {
-	c *net.IPConn
+	*net.IPConn
+	*socket.Conn
 	rawOpt
 }
 
-func (c *packetHandler) ok() bool { return c != nil && c.c != nil }
+func (c *packetHandler) ok() bool { return c != nil && c.IPConn != nil && c.Conn != nil }
 
 // ReadFrom reads an IPv4 datagram from the endpoint c, copying the
 // datagram into b. It returns the received datagram as the IPv4
@@ -27,25 +30,7 @@ func (c *packetHandler) ReadFrom(b []byte) (h *Header, p []byte, cm *ControlMess
 	if !c.ok() {
 		return nil, nil, nil, syscall.EINVAL
 	}
-	oob := newControlMessage(&c.rawOpt)
-	n, oobn, _, src, err := c.c.ReadMsgIP(b, oob)
-	if err != nil {
-		return nil, nil, nil, err
-	}
-	var hs []byte
-	if hs, p, err = slicePacket(b[:n]); err != nil {
-		return nil, nil, nil, err
-	}
-	if h, err = ParseHeader(hs); err != nil {
-		return nil, nil, nil, err
-	}
-	if cm, err = parseControlMessage(oob[:oobn]); err != nil {
-		return nil, nil, nil, err
-	}
-	if src != nil && cm != nil {
-		cm.Src = src.IP
-	}
-	return
+	return c.readFrom(b)
 }
 
 func slicePacket(b []byte) (h, p []byte, err error) {
@@ -80,21 +65,5 @@ func (c *packetHandler) WriteTo(h *Header, p []byte, cm *ControlMessage) error {
 	if !c.ok() {
 		return syscall.EINVAL
 	}
-	oob := marshalControlMessage(cm)
-	wh, err := h.Marshal()
-	if err != nil {
-		return err
-	}
-	dst := &net.IPAddr{}
-	if cm != nil {
-		if ip := cm.Dst.To4(); ip != nil {
-			dst.IP = ip
-		}
-	}
-	if dst.IP == nil {
-		dst.IP = h.Dst
-	}
-	wh = append(wh, p...)
-	_, _, err = c.c.WriteMsgIP(wh, oob, dst)
-	return err
+	return c.writeTo(h, p, cm)
 }
diff --git a/ipv4/packet_go1_8.go b/ipv4/packet_go1_8.go
new file mode 100644
index 00000000..b47d1868
--- /dev/null
+++ b/ipv4/packet_go1_8.go
@@ -0,0 +1,56 @@
+// Copyright 2012 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.
+
+// +build !go1.9
+
+package ipv4
+
+import "net"
+
+func (c *packetHandler) readFrom(b []byte) (h *Header, p []byte, cm *ControlMessage, err error) {
+	c.rawOpt.RLock()
+	oob := NewControlMessage(c.rawOpt.cflags)
+	c.rawOpt.RUnlock()
+	n, nn, _, src, err := c.ReadMsgIP(b, oob)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+	var hs []byte
+	if hs, p, err = slicePacket(b[:n]); err != nil {
+		return nil, nil, nil, err
+	}
+	if h, err = ParseHeader(hs); err != nil {
+		return nil, nil, nil, err
+	}
+	if nn > 0 {
+		cm = new(ControlMessage)
+		if err := cm.Parse(oob[:nn]); err != nil {
+			return nil, nil, nil, err
+		}
+	}
+	if src != nil && cm != nil {
+		cm.Src = src.IP
+	}
+	return
+}
+
+func (c *packetHandler) writeTo(h *Header, p []byte, cm *ControlMessage) error {
+	oob := cm.Marshal()
+	wh, err := h.Marshal()
+	if err != nil {
+		return err
+	}
+	dst := new(net.IPAddr)
+	if cm != nil {
+		if ip := cm.Dst.To4(); ip != nil {
+			dst.IP = ip
+		}
+	}
+	if dst.IP == nil {
+		dst.IP = h.Dst
+	}
+	wh = append(wh, p...)
+	_, _, err = c.WriteMsgIP(wh, oob, dst)
+	return err
+}
diff --git a/ipv4/packet_go1_9.go b/ipv4/packet_go1_9.go
new file mode 100644
index 00000000..285fdb0e
--- /dev/null
+++ b/ipv4/packet_go1_9.go
@@ -0,0 +1,67 @@
+// Copyright 2017 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.
+
+// +build go1.9
+
+package ipv4
+
+import (
+	"net"
+
+	"golang.org/x/net/internal/socket"
+)
+
+func (c *packetHandler) readFrom(b []byte) (h *Header, p []byte, cm *ControlMessage, err error) {
+	c.rawOpt.RLock()
+	m := socket.Message{
+		Buffers: [][]byte{b},
+		OOB:     NewControlMessage(c.rawOpt.cflags),
+	}
+	c.rawOpt.RUnlock()
+	if err := c.RecvMsg(&m, 0); err != nil {
+		return nil, nil, nil, &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+	}
+	var hs []byte
+	if hs, p, err = slicePacket(b[:m.N]); err != nil {
+		return nil, nil, nil, &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+	}
+	if h, err = ParseHeader(hs); err != nil {
+		return nil, nil, nil, &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+	}
+	if m.NN > 0 {
+		cm = new(ControlMessage)
+		if err := cm.Parse(m.OOB[:m.NN]); err != nil {
+			return nil, nil, nil, &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+		}
+	}
+	if src, ok := m.Addr.(*net.IPAddr); ok && cm != nil {
+		cm.Src = src.IP
+	}
+	return
+}
+
+func (c *packetHandler) writeTo(h *Header, p []byte, cm *ControlMessage) error {
+	m := socket.Message{
+		OOB: cm.Marshal(),
+	}
+	wh, err := h.Marshal()
+	if err != nil {
+		return err
+	}
+	m.Buffers = [][]byte{wh, p}
+	dst := new(net.IPAddr)
+	if cm != nil {
+		if ip := cm.Dst.To4(); ip != nil {
+			dst.IP = ip
+		}
+	}
+	if dst.IP == nil {
+		dst.IP = h.Dst
+	}
+	m.Addr = dst
+	if err := c.SendMsg(&m, 0); err != nil {
+		return &net.OpError{Op: "write", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+	}
+	return nil
+}
diff --git a/ipv4/payload.go b/ipv4/payload.go
index be130e42..f95f811a 100644
--- a/ipv4/payload.go
+++ b/ipv4/payload.go
@@ -4,7 +4,11 @@
 
 package ipv4
 
-import "net"
+import (
+	"net"
+
+	"golang.org/x/net/internal/socket"
+)
 
 // BUG(mikio): On Windows, the ControlMessage for ReadFrom and WriteTo
 // methods of PacketConn is not implemented.
@@ -12,7 +16,8 @@ import "net"
 // A payloadHandler represents the IPv4 datagram payload handler.
 type payloadHandler struct {
 	net.PacketConn
+	*socket.Conn
 	rawOpt
 }
 
-func (c *payloadHandler) ok() bool { return c != nil && c.PacketConn != nil }
+func (c *payloadHandler) ok() bool { return c != nil && c.PacketConn != nil && c.Conn != nil }
diff --git a/ipv4/payload_cmsg.go b/ipv4/payload_cmsg.go
index 9a155d25..3f06d760 100644
--- a/ipv4/payload_cmsg.go
+++ b/ipv4/payload_cmsg.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !plan9,!windows
+// +build !nacl,!plan9,!windows
 
 package ipv4
 
@@ -19,37 +19,7 @@ func (c *payloadHandler) ReadFrom(b []byte) (n int, cm *ControlMessage, src net.
 	if !c.ok() {
 		return 0, nil, nil, syscall.EINVAL
 	}
-	oob := newControlMessage(&c.rawOpt)
-	var oobn int
-	switch c := c.PacketConn.(type) {
-	case *net.UDPConn:
-		if n, oobn, _, src, err = c.ReadMsgUDP(b, oob); err != nil {
-			return 0, nil, nil, err
-		}
-	case *net.IPConn:
-		if _, ok := sockOpts[ssoStripHeader]; ok {
-			if n, oobn, _, src, err = c.ReadMsgIP(b, oob); err != nil {
-				return 0, nil, nil, err
-			}
-		} else {
-			nb := make([]byte, maxHeaderLen+len(b))
-			if n, oobn, _, src, err = c.ReadMsgIP(nb, oob); err != nil {
-				return 0, nil, nil, err
-			}
-			hdrlen := int(nb[0]&0x0f) << 2
-			copy(b, nb[hdrlen:])
-			n -= hdrlen
-		}
-	default:
-		return 0, nil, nil, errInvalidConnType
-	}
-	if cm, err = parseControlMessage(oob[:oobn]); err != nil {
-		return 0, nil, nil, err
-	}
-	if cm != nil {
-		cm.Src = netAddrToIP4(src)
-	}
-	return
+	return c.readFrom(b)
 }
 
 // WriteTo writes a payload of the IPv4 datagram, to the destination
@@ -62,20 +32,5 @@ func (c *payloadHandler) WriteTo(b []byte, cm *ControlMessage, dst net.Addr) (n
 	if !c.ok() {
 		return 0, syscall.EINVAL
 	}
-	oob := marshalControlMessage(cm)
-	if dst == nil {
-		return 0, errMissingAddress
-	}
-	switch c := c.PacketConn.(type) {
-	case *net.UDPConn:
-		n, _, err = c.WriteMsgUDP(b, oob, dst.(*net.UDPAddr))
-	case *net.IPConn:
-		n, _, err = c.WriteMsgIP(b, oob, dst.(*net.IPAddr))
-	default:
-		return 0, errInvalidConnType
-	}
-	if err != nil {
-		return 0, err
-	}
-	return
+	return c.writeTo(b, cm, dst)
 }
diff --git a/ipv4/payload_cmsg_go1_8.go b/ipv4/payload_cmsg_go1_8.go
new file mode 100644
index 00000000..0a9c33a1
--- /dev/null
+++ b/ipv4/payload_cmsg_go1_8.go
@@ -0,0 +1,59 @@
+// Copyright 2012 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.
+
+// +build !go1.9
+// +build !nacl,!plan9,!windows
+
+package ipv4
+
+import "net"
+
+func (c *payloadHandler) readFrom(b []byte) (n int, cm *ControlMessage, src net.Addr, err error) {
+	c.rawOpt.RLock()
+	oob := NewControlMessage(c.rawOpt.cflags)
+	c.rawOpt.RUnlock()
+	var nn int
+	switch c := c.PacketConn.(type) {
+	case *net.UDPConn:
+		if n, nn, _, src, err = c.ReadMsgUDP(b, oob); err != nil {
+			return 0, nil, nil, err
+		}
+	case *net.IPConn:
+		nb := make([]byte, maxHeaderLen+len(b))
+		if n, nn, _, src, err = c.ReadMsgIP(nb, oob); err != nil {
+			return 0, nil, nil, err
+		}
+		hdrlen := int(nb[0]&0x0f) << 2
+		copy(b, nb[hdrlen:])
+		n -= hdrlen
+	default:
+		return 0, nil, nil, &net.OpError{Op: "read", Net: c.LocalAddr().Network(), Source: c.LocalAddr(), Err: errInvalidConnType}
+	}
+	if nn > 0 {
+		cm = new(ControlMessage)
+		if err = cm.Parse(oob[:nn]); err != nil {
+			return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+		}
+	}
+	if cm != nil {
+		cm.Src = netAddrToIP4(src)
+	}
+	return
+}
+
+func (c *payloadHandler) writeTo(b []byte, cm *ControlMessage, dst net.Addr) (n int, err error) {
+	oob := cm.Marshal()
+	if dst == nil {
+		return 0, &net.OpError{Op: "write", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: errMissingAddress}
+	}
+	switch c := c.PacketConn.(type) {
+	case *net.UDPConn:
+		n, _, err = c.WriteMsgUDP(b, oob, dst.(*net.UDPAddr))
+	case *net.IPConn:
+		n, _, err = c.WriteMsgIP(b, oob, dst.(*net.IPAddr))
+	default:
+		return 0, &net.OpError{Op: "write", Net: c.LocalAddr().Network(), Source: c.LocalAddr(), Err: errInvalidConnType}
+	}
+	return
+}
diff --git a/ipv4/payload_cmsg_go1_9.go b/ipv4/payload_cmsg_go1_9.go
new file mode 100644
index 00000000..e697f35f
--- /dev/null
+++ b/ipv4/payload_cmsg_go1_9.go
@@ -0,0 +1,67 @@
+// Copyright 2017 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.
+
+// +build go1.9
+// +build !nacl,!plan9,!windows
+
+package ipv4
+
+import (
+	"net"
+
+	"golang.org/x/net/internal/socket"
+)
+
+func (c *payloadHandler) readFrom(b []byte) (int, *ControlMessage, net.Addr, error) {
+	c.rawOpt.RLock()
+	m := socket.Message{
+		OOB: NewControlMessage(c.rawOpt.cflags),
+	}
+	c.rawOpt.RUnlock()
+	switch c.PacketConn.(type) {
+	case *net.UDPConn:
+		m.Buffers = [][]byte{b}
+		if err := c.RecvMsg(&m, 0); err != nil {
+			return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+		}
+	case *net.IPConn:
+		h := make([]byte, HeaderLen)
+		m.Buffers = [][]byte{h, b}
+		if err := c.RecvMsg(&m, 0); err != nil {
+			return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+		}
+		hdrlen := int(h[0]&0x0f) << 2
+		if hdrlen > len(h) {
+			d := hdrlen - len(h)
+			copy(b, b[d:])
+			m.N -= d
+		} else {
+			m.N -= hdrlen
+		}
+	default:
+		return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: errInvalidConnType}
+	}
+	var cm *ControlMessage
+	if m.NN > 0 {
+		cm = new(ControlMessage)
+		if err := cm.Parse(m.OOB[:m.NN]); err != nil {
+			return 0, nil, nil, &net.OpError{Op: "read", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+		}
+		cm.Src = netAddrToIP4(m.Addr)
+	}
+	return m.N, cm, m.Addr, nil
+}
+
+func (c *payloadHandler) writeTo(b []byte, cm *ControlMessage, dst net.Addr) (int, error) {
+	m := socket.Message{
+		Buffers: [][]byte{b},
+		OOB:     cm.Marshal(),
+		Addr:    dst,
+	}
+	err := c.SendMsg(&m, 0)
+	if err != nil {
+		err = &net.OpError{Op: "write", Net: c.PacketConn.LocalAddr().Network(), Source: c.PacketConn.LocalAddr(), Err: err}
+	}
+	return m.N, err
+}
diff --git a/ipv4/payload_nocmsg.go b/ipv4/payload_nocmsg.go
index 6f9d5b0e..3926de70 100644
--- a/ipv4/payload_nocmsg.go
+++ b/ipv4/payload_nocmsg.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build plan9 windows
+// +build nacl plan9 windows
 
 package ipv4
 
diff --git a/ipv4/readwrite_go1_8_test.go b/ipv4/readwrite_go1_8_test.go
new file mode 100644
index 00000000..1cd926e7
--- /dev/null
+++ b/ipv4/readwrite_go1_8_test.go
@@ -0,0 +1,248 @@
+// Copyright 2012 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.
+
+// +build !go1.9
+
+package ipv4_test
+
+import (
+	"bytes"
+	"fmt"
+	"net"
+	"runtime"
+	"strings"
+	"sync"
+	"testing"
+
+	"golang.org/x/net/internal/iana"
+	"golang.org/x/net/internal/nettest"
+	"golang.org/x/net/ipv4"
+)
+
+func BenchmarkPacketConnReadWriteUnicast(b *testing.B) {
+	switch runtime.GOOS {
+	case "nacl", "plan9", "windows":
+		b.Skipf("not supported on %s", runtime.GOOS)
+	}
+
+	payload := []byte("HELLO-R-U-THERE")
+	iph, err := (&ipv4.Header{
+		Version:  ipv4.Version,
+		Len:      ipv4.HeaderLen,
+		TotalLen: ipv4.HeaderLen + len(payload),
+		TTL:      1,
+		Protocol: iana.ProtocolReserved,
+		Src:      net.IPv4(192, 0, 2, 1),
+		Dst:      net.IPv4(192, 0, 2, 254),
+	}).Marshal()
+	if err != nil {
+		b.Fatal(err)
+	}
+	greh := []byte{0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00}
+	datagram := append(greh, append(iph, payload...)...)
+	bb := make([]byte, 128)
+	cm := ipv4.ControlMessage{
+		Src: net.IPv4(127, 0, 0, 1),
+	}
+	if ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback); ifi != nil {
+		cm.IfIndex = ifi.Index
+	}
+
+	b.Run("UDP", func(b *testing.B) {
+		c, err := nettest.NewLocalPacketListener("udp4")
+		if err != nil {
+			b.Skipf("not supported on %s/%s: %v", runtime.GOOS, runtime.GOARCH, err)
+		}
+		defer c.Close()
+		p := ipv4.NewPacketConn(c)
+		dst := c.LocalAddr()
+		cf := ipv4.FlagTTL | ipv4.FlagInterface
+		if err := p.SetControlMessage(cf, true); err != nil {
+			b.Fatal(err)
+		}
+		b.Run("Net", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := c.WriteTo(payload, dst); err != nil {
+					b.Fatal(err)
+				}
+				if _, _, err := c.ReadFrom(bb); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+		b.Run("ToFrom", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := p.WriteTo(payload, &cm, dst); err != nil {
+					b.Fatal(err)
+				}
+				if _, _, _, err := p.ReadFrom(bb); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	})
+	b.Run("IP", func(b *testing.B) {
+		switch runtime.GOOS {
+		case "netbsd":
+			b.Skip("need to configure gre on netbsd")
+		case "openbsd":
+			b.Skip("net.inet.gre.allow=0 by default on openbsd")
+		}
+
+		c, err := net.ListenPacket(fmt.Sprintf("ip4:%d", iana.ProtocolGRE), "127.0.0.1")
+		if err != nil {
+			b.Skipf("not supported on %s/%s: %v", runtime.GOOS, runtime.GOARCH, err)
+		}
+		defer c.Close()
+		p := ipv4.NewPacketConn(c)
+		dst := c.LocalAddr()
+		cf := ipv4.FlagTTL | ipv4.FlagInterface
+		if err := p.SetControlMessage(cf, true); err != nil {
+			b.Fatal(err)
+		}
+		b.Run("Net", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := c.WriteTo(datagram, dst); err != nil {
+					b.Fatal(err)
+				}
+				if _, _, err := c.ReadFrom(bb); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+		b.Run("ToFrom", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := p.WriteTo(datagram, &cm, dst); err != nil {
+					b.Fatal(err)
+				}
+				if _, _, _, err := p.ReadFrom(bb); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	})
+}
+
+func TestPacketConnConcurrentReadWriteUnicast(t *testing.T) {
+	switch runtime.GOOS {
+	case "nacl", "plan9", "windows":
+		t.Skipf("not supported on %s", runtime.GOOS)
+	}
+
+	payload := []byte("HELLO-R-U-THERE")
+	iph, err := (&ipv4.Header{
+		Version:  ipv4.Version,
+		Len:      ipv4.HeaderLen,
+		TotalLen: ipv4.HeaderLen + len(payload),
+		TTL:      1,
+		Protocol: iana.ProtocolReserved,
+		Src:      net.IPv4(192, 0, 2, 1),
+		Dst:      net.IPv4(192, 0, 2, 254),
+	}).Marshal()
+	if err != nil {
+		t.Fatal(err)
+	}
+	greh := []byte{0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00}
+	datagram := append(greh, append(iph, payload...)...)
+
+	t.Run("UDP", func(t *testing.T) {
+		c, err := nettest.NewLocalPacketListener("udp4")
+		if err != nil {
+			t.Skipf("not supported on %s/%s: %v", runtime.GOOS, runtime.GOARCH, err)
+		}
+		defer c.Close()
+		p := ipv4.NewPacketConn(c)
+		t.Run("ToFrom", func(t *testing.T) {
+			testPacketConnConcurrentReadWriteUnicast(t, p, payload, c.LocalAddr())
+		})
+	})
+	t.Run("IP", func(t *testing.T) {
+		switch runtime.GOOS {
+		case "netbsd":
+			t.Skip("need to configure gre on netbsd")
+		case "openbsd":
+			t.Skip("net.inet.gre.allow=0 by default on openbsd")
+		}
+
+		c, err := net.ListenPacket(fmt.Sprintf("ip4:%d", iana.ProtocolGRE), "127.0.0.1")
+		if err != nil {
+			t.Skipf("not supported on %s/%s: %v", runtime.GOOS, runtime.GOARCH, err)
+		}
+		defer c.Close()
+		p := ipv4.NewPacketConn(c)
+		t.Run("ToFrom", func(t *testing.T) {
+			testPacketConnConcurrentReadWriteUnicast(t, p, datagram, c.LocalAddr())
+		})
+	})
+}
+
+func testPacketConnConcurrentReadWriteUnicast(t *testing.T, p *ipv4.PacketConn, data []byte, dst net.Addr) {
+	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
+	cf := ipv4.FlagTTL | ipv4.FlagSrc | ipv4.FlagDst | ipv4.FlagInterface
+
+	if err := p.SetControlMessage(cf, true); err != nil { // probe before test
+		if nettest.ProtocolNotSupported(err) {
+			t.Skipf("not supported on %s", runtime.GOOS)
+		}
+		t.Fatal(err)
+	}
+
+	var wg sync.WaitGroup
+	reader := func() {
+		defer wg.Done()
+		b := make([]byte, 128)
+		n, cm, _, err := p.ReadFrom(b)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		if !bytes.Equal(b[:n], data) {
+			t.Errorf("got %#v; want %#v", b[:n], data)
+			return
+		}
+		s := cm.String()
+		if strings.Contains(s, ",") {
+			t.Errorf("should be space-separated values: %s", s)
+			return
+		}
+	}
+	writer := func(toggle bool) {
+		defer wg.Done()
+		cm := ipv4.ControlMessage{
+			Src: net.IPv4(127, 0, 0, 1),
+		}
+		if ifi != nil {
+			cm.IfIndex = ifi.Index
+		}
+		if err := p.SetControlMessage(cf, toggle); err != nil {
+			t.Error(err)
+			return
+		}
+		n, err := p.WriteTo(data, &cm, dst)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		if n != len(data) {
+			t.Errorf("got %d; want %d", n, len(data))
+			return
+		}
+	}
+
+	const N = 10
+	wg.Add(N)
+	for i := 0; i < N; i++ {
+		go reader()
+	}
+	wg.Add(2 * N)
+	for i := 0; i < 2*N; i++ {
+		go writer(i%2 != 0)
+
+	}
+	wg.Add(N)
+	for i := 0; i < N; i++ {
+		go reader()
+	}
+	wg.Wait()
+}
diff --git a/ipv4/readwrite_go1_9_test.go b/ipv4/readwrite_go1_9_test.go
new file mode 100644
index 00000000..365de022
--- /dev/null
+++ b/ipv4/readwrite_go1_9_test.go
@@ -0,0 +1,388 @@
+// Copyright 2017 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.
+
+// +build go1.9
+
+package ipv4_test
+
+import (
+	"bytes"
+	"fmt"
+	"net"
+	"runtime"
+	"strings"
+	"sync"
+	"testing"
+
+	"golang.org/x/net/internal/iana"
+	"golang.org/x/net/internal/nettest"
+	"golang.org/x/net/ipv4"
+)
+
+func BenchmarkPacketConnReadWriteUnicast(b *testing.B) {
+	switch runtime.GOOS {
+	case "nacl", "plan9", "windows":
+		b.Skipf("not supported on %s", runtime.GOOS)
+	}
+
+	payload := []byte("HELLO-R-U-THERE")
+	iph, err := (&ipv4.Header{
+		Version:  ipv4.Version,
+		Len:      ipv4.HeaderLen,
+		TotalLen: ipv4.HeaderLen + len(payload),
+		TTL:      1,
+		Protocol: iana.ProtocolReserved,
+		Src:      net.IPv4(192, 0, 2, 1),
+		Dst:      net.IPv4(192, 0, 2, 254),
+	}).Marshal()
+	if err != nil {
+		b.Fatal(err)
+	}
+	greh := []byte{0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00}
+	datagram := append(greh, append(iph, payload...)...)
+	bb := make([]byte, 128)
+	cm := ipv4.ControlMessage{
+		Src: net.IPv4(127, 0, 0, 1),
+	}
+	if ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback); ifi != nil {
+		cm.IfIndex = ifi.Index
+	}
+
+	b.Run("UDP", func(b *testing.B) {
+		c, err := nettest.NewLocalPacketListener("udp4")
+		if err != nil {
+			b.Skipf("not supported on %s/%s: %v", runtime.GOOS, runtime.GOARCH, err)
+		}
+		defer c.Close()
+		p := ipv4.NewPacketConn(c)
+		dst := c.LocalAddr()
+		cf := ipv4.FlagTTL | ipv4.FlagInterface
+		if err := p.SetControlMessage(cf, true); err != nil {
+			b.Fatal(err)
+		}
+		wms := []ipv4.Message{
+			{
+				Buffers: [][]byte{payload},
+				Addr:    dst,
+				OOB:     cm.Marshal(),
+			},
+		}
+		rms := []ipv4.Message{
+			{
+				Buffers: [][]byte{bb},
+				OOB:     ipv4.NewControlMessage(cf),
+			},
+		}
+		b.Run("Net", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := c.WriteTo(payload, dst); err != nil {
+					b.Fatal(err)
+				}
+				if _, _, err := c.ReadFrom(bb); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+		b.Run("ToFrom", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := p.WriteTo(payload, &cm, dst); err != nil {
+					b.Fatal(err)
+				}
+				if _, _, _, err := p.ReadFrom(bb); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+		b.Run("Batch", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := p.WriteBatch(wms, 0); err != nil {
+					b.Fatal(err)
+				}
+				if _, err := p.ReadBatch(rms, 0); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	})
+	b.Run("IP", func(b *testing.B) {
+		switch runtime.GOOS {
+		case "netbsd":
+			b.Skip("need to configure gre on netbsd")
+		case "openbsd":
+			b.Skip("net.inet.gre.allow=0 by default on openbsd")
+		}
+
+		c, err := net.ListenPacket(fmt.Sprintf("ip4:%d", iana.ProtocolGRE), "127.0.0.1")
+		if err != nil {
+			b.Skipf("not supported on %s/%s: %v", runtime.GOOS, runtime.GOARCH, err)
+		}
+		defer c.Close()
+		p := ipv4.NewPacketConn(c)
+		dst := c.LocalAddr()
+		cf := ipv4.FlagTTL | ipv4.FlagInterface
+		if err := p.SetControlMessage(cf, true); err != nil {
+			b.Fatal(err)
+		}
+		wms := []ipv4.Message{
+			{
+				Buffers: [][]byte{datagram},
+				Addr:    dst,
+				OOB:     cm.Marshal(),
+			},
+		}
+		rms := []ipv4.Message{
+			{
+				Buffers: [][]byte{bb},
+				OOB:     ipv4.NewControlMessage(cf),
+			},
+		}
+		b.Run("Net", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := c.WriteTo(datagram, dst); err != nil {
+					b.Fatal(err)
+				}
+				if _, _, err := c.ReadFrom(bb); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+		b.Run("ToFrom", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := p.WriteTo(datagram, &cm, dst); err != nil {
+					b.Fatal(err)
+				}
+				if _, _, _, err := p.ReadFrom(bb); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+		b.Run("Batch", func(b *testing.B) {
+			for i := 0; i < b.N; i++ {
+				if _, err := p.WriteBatch(wms, 0); err != nil {
+					b.Fatal(err)
+				}
+				if _, err := p.ReadBatch(rms, 0); err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	})
+}
+
+func TestPacketConnConcurrentReadWriteUnicast(t *testing.T) {
+	switch runtime.GOOS {
+	case "nacl", "plan9", "windows":
+		t.Skipf("not supported on %s", runtime.GOOS)
+	}
+
+	payload := []byte("HELLO-R-U-THERE")
+	iph, err := (&ipv4.Header{
+		Version:  ipv4.Version,
+		Len:      ipv4.HeaderLen,
+		TotalLen: ipv4.HeaderLen + len(payload),
+		TTL:      1,
+		Protocol: iana.ProtocolReserved,
+		Src:      net.IPv4(192, 0, 2, 1),
+		Dst:      net.IPv4(192, 0, 2, 254),
+	}).Marshal()
+	if err != nil {
+		t.Fatal(err)
+	}
+	greh := []byte{0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00}
+	datagram := append(greh, append(iph, payload...)...)
+
+	t.Run("UDP", func(t *testing.T) {
+		c, err := nettest.NewLocalPacketListener("udp4")
+		if err != nil {
+			t.Skipf("not supported on %s/%s: %v", runtime.GOOS, runtime.GOARCH, err)
+		}
+		defer c.Close()
+		p := ipv4.NewPacketConn(c)
+		t.Run("ToFrom", func(t *testing.T) {
+			testPacketConnConcurrentReadWriteUnicast(t, p, payload, c.LocalAddr(), false)
+		})
+		t.Run("Batch", func(t *testing.T) {
+			testPacketConnConcurrentReadWriteUnicast(t, p, payload, c.LocalAddr(), true)
+		})
+	})
+	t.Run("IP", func(t *testing.T) {
+		switch runtime.GOOS {
+		case "netbsd":
+			t.Skip("need to configure gre on netbsd")
+		case "openbsd":
+			t.Skip("net.inet.gre.allow=0 by default on openbsd")
+		}
+
+		c, err := net.ListenPacket(fmt.Sprintf("ip4:%d", iana.ProtocolGRE), "127.0.0.1")
+		if err != nil {
+			t.Skipf("not supported on %s/%s: %v", runtime.GOOS, runtime.GOARCH, err)
+		}
+		defer c.Close()
+		p := ipv4.NewPacketConn(c)
+		t.Run("ToFrom", func(t *testing.T) {
+			testPacketConnConcurrentReadWriteUnicast(t, p, datagram, c.LocalAddr(), false)
+		})
+		t.Run("Batch", func(t *testing.T) {
+			testPacketConnConcurrentReadWriteUnicast(t, p, datagram, c.LocalAddr(), true)
+		})
+	})
+}
+
+func testPacketConnConcurrentReadWriteUnicast(t *testing.T, p *ipv4.PacketConn, data []byte, dst net.Addr, batch bool) {
+	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
+	cf := ipv4.FlagTTL | ipv4.FlagSrc | ipv4.FlagDst | ipv4.FlagInterface
+
+	if err := p.SetControlMessage(cf, true); err != nil { // probe before test
+		if nettest.ProtocolNotSupported(err) {
+			t.Skipf("not supported on %s", runtime.GOOS)
+		}
+		t.Fatal(err)
+	}
+
+	var wg sync.WaitGroup
+	reader := func() {
+		defer wg.Done()
+		b := make([]byte, 128)
+		n, cm, _, err := p.ReadFrom(b)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		if !bytes.Equal(b[:n], data) {
+			t.Errorf("got %#v; want %#v", b[:n], data)
+			return
+		}
+		s := cm.String()
+		if strings.Contains(s, ",") {
+			t.Errorf("should be space-separated values: %s", s)
+			return
+		}
+	}
+	batchReader := func() {
+		defer wg.Done()
+		ms := []ipv4.Message{
+			{
+				Buffers: [][]byte{make([]byte, 128)},
+				OOB:     ipv4.NewControlMessage(cf),
+			},
+		}
+		n, err := p.ReadBatch(ms, 0)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		if n != len(ms) {
+			t.Errorf("got %d; want %d", n, len(ms))
+			return
+		}
+		var cm ipv4.ControlMessage
+		if err := cm.Parse(ms[0].OOB[:ms[0].NN]); err != nil {
+			t.Error(err)
+			return
+		}
+		var b []byte
+		if _, ok := dst.(*net.IPAddr); ok {
+			var h ipv4.Header
+			if err := h.Parse(ms[0].Buffers[0][:ms[0].N]); err != nil {
+				t.Error(err)
+				return
+			}
+			b = ms[0].Buffers[0][h.Len:ms[0].N]
+		} else {
+			b = ms[0].Buffers[0][:ms[0].N]
+		}
+		if !bytes.Equal(b, data) {
+			t.Errorf("got %#v; want %#v", b, data)
+			return
+		}
+		s := cm.String()
+		if strings.Contains(s, ",") {
+			t.Errorf("should be space-separated values: %s", s)
+			return
+		}
+	}
+	writer := func(toggle bool) {
+		defer wg.Done()
+		cm := ipv4.ControlMessage{
+			Src: net.IPv4(127, 0, 0, 1),
+		}
+		if ifi != nil {
+			cm.IfIndex = ifi.Index
+		}
+		if err := p.SetControlMessage(cf, toggle); err != nil {
+			t.Error(err)
+			return
+		}
+		n, err := p.WriteTo(data, &cm, dst)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		if n != len(data) {
+			t.Errorf("got %d; want %d", n, len(data))
+			return
+		}
+	}
+	batchWriter := func(toggle bool) {
+		defer wg.Done()
+		cm := ipv4.ControlMessage{
+			Src: net.IPv4(127, 0, 0, 1),
+		}
+		if ifi != nil {
+			cm.IfIndex = ifi.Index
+		}
+		if err := p.SetControlMessage(cf, toggle); err != nil {
+			t.Error(err)
+			return
+		}
+		ms := []ipv4.Message{
+			{
+				Buffers: [][]byte{data},
+				OOB:     cm.Marshal(),
+				Addr:    dst,
+			},
+		}
+		n, err := p.WriteBatch(ms, 0)
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		if n != len(ms) {
+			t.Errorf("got %d; want %d", n, len(ms))
+			return
+		}
+		if ms[0].N != len(data) {
+			t.Errorf("got %d; want %d", ms[0].N, len(data))
+			return
+		}
+	}
+
+	const N = 10
+	wg.Add(N)
+	for i := 0; i < N; i++ {
+		if batch {
+			go batchReader()
+		} else {
+			go reader()
+		}
+	}
+	wg.Add(2 * N)
+	for i := 0; i < 2*N; i++ {
+		if batch {
+			go batchWriter(i%2 != 0)
+		} else {
+			go writer(i%2 != 0)
+		}
+
+	}
+	wg.Add(N)
+	for i := 0; i < N; i++ {
+		if batch {
+			go batchReader()
+		} else {
+			go reader()
+		}
+	}
+	wg.Wait()
+}