go.net/ipv6: restore use of syscall

This CL restores use of syscall functions and constants that
doesn't break the build on Go 1.1 and beyond.

LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/92320046

ipv6/sockopt_rfc2292_unix.go

@@ -8,6 +8,7 @@ package ipv6
 
 import (
 	"os"
+	"syscall"
 	"unsafe"
 )
 
@@ -20,31 +21,27 @@ func setIPv6ReceiveTrafficClass(fd int, v bool) error {
 }
 
 func ipv6ReceiveHopLimit(fd int) (bool, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockopt2292HopLimit, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockopt2292HopLimit)
+	if err != nil {
 		return false, os.NewSyscallError("getsockopt", err)
 	}
 	return v == 1, nil
 }
 
 func setIPv6ReceiveHopLimit(fd int, v bool) error {
-	vv := int32(boolint(v))
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockopt2292HopLimit, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockopt2292HopLimit, boolint(v)))
 }
 
 func ipv6ReceivePacketInfo(fd int) (bool, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockopt2292PacketInfo, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockopt2292PacketInfo)
+	if err != nil {
 		return false, os.NewSyscallError("getsockopt", err)
 	}
 	return v == 1, nil
 }
 
 func setIPv6ReceivePacketInfo(fd int, v bool) error {
-	vv := int32(boolint(v))
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockopt2292PacketInfo, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockopt2292PacketInfo, boolint(v)))
 }
 
 func ipv6PathMTU(fd int) (int, error) {

ipv6/sockopt_rfc3493_bsd.go

@@ -8,13 +8,12 @@ package ipv6
 
 import (
 	"os"
-	"unsafe"
+	"syscall"
 )
 
 func setIPv6Checksum(fd int, on bool, offset int) error {
 	if !on {
 		offset = -1
 	}
-	v := int32(offset)
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptChecksum, unsafe.Pointer(&v), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptChecksum, offset))
 }

ipv6/sockopt_rfc3493_linux.go

@@ -6,13 +6,12 @@ package ipv6
 
 import (
 	"os"
-	"unsafe"
+	"syscall"
 )
 
 func setIPv6Checksum(fd int, on bool, offset int) error {
 	if !on {
 		offset = -1
 	}
-	v := int32(offset)
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolReserved, sysSockoptChecksum, unsafe.Pointer(&v), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolReserved, sysSockoptChecksum, offset))
 }

ipv6/sockopt_rfc3493_unix.go

@@ -9,74 +9,67 @@ package ipv6
 import (
 	"net"
 	"os"
+	"syscall"
 	"unsafe"
 )
 
 func ipv6TrafficClass(fd int) (int, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptTrafficClass, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptTrafficClass)
+	if err != nil {
 		return 0, os.NewSyscallError("getsockopt", err)
 	}
-	return int(v), nil
+	return v, nil
 }
 
 func setIPv6TrafficClass(fd, v int) error {
-	vv := int32(v)
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptTrafficClass, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptTrafficClass, v))
 }
 
 func ipv6HopLimit(fd int) (int, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptUnicastHopLimit, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptUnicastHopLimit)
+	if err != nil {
 		return 0, os.NewSyscallError("getsockopt", err)
 	}
-	return int(v), nil
+	return v, nil
 }
 
 func setIPv6HopLimit(fd, v int) error {
-	vv := int32(v)
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptUnicastHopLimit, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptUnicastHopLimit, v))
 }
 
 func ipv6Checksum(fd int) (bool, int, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptChecksum, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptChecksum)
+	if err != nil {
 		return false, 0, os.NewSyscallError("getsockopt", err)
 	}
 	on := true
 	if v == -1 {
 		on = false
 	}
-	return on, int(v), nil
+	return on, v, nil
 }
 
 func ipv6MulticastHopLimit(fd int) (int, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptMulticastHopLimit, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptMulticastHopLimit)
+	if err != nil {
 		return 0, os.NewSyscallError("getsockopt", err)
 	}
-	return int(v), nil
+	return v, nil
 }
 
 func setIPv6MulticastHopLimit(fd, v int) error {
-	vv := int32(v)
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptMulticastHopLimit, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptMulticastHopLimit, v))
 }
 
 func ipv6MulticastInterface(fd int) (*net.Interface, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptMulticastInterface, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptMulticastInterface)
+	if err != nil {
 		return nil, os.NewSyscallError("getsockopt", err)
 	}
 	if v == 0 {
 		return nil, nil
 	}
-	ifi, err := net.InterfaceByIndex(int(v))
+	ifi, err := net.InterfaceByIndex(v)
 	if err != nil {
 		return nil, err
 	}
@@ -84,25 +77,23 @@ func ipv6MulticastInterface(fd int) (*net.Interface, error) {
 }
 
 func setIPv6MulticastInterface(fd int, ifi *net.Interface) error {
-	var v int32
+	var v int
 	if ifi != nil {
-		v = int32(ifi.Index)
+		v = ifi.Index
 	}
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptMulticastInterface, unsafe.Pointer(&v), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptMulticastInterface, v))
 }
 
 func ipv6MulticastLoopback(fd int) (bool, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptMulticastLoopback, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptMulticastLoopback)
+	if err != nil {
 		return false, os.NewSyscallError("getsockopt", err)
 	}
 	return v == 1, nil
 }
 
 func setIPv6MulticastLoopback(fd int, v bool) error {
-	vv := int32(boolint(v))
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptMulticastLoopback, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptMulticastLoopback, boolint(v)))
 }
 
 func joinIPv6Group(fd int, ifi *net.Interface, grp net.IP) error {

ipv6/sockopt_rfc3542_unix.go

@@ -8,49 +8,44 @@ package ipv6
 
 import (
 	"os"
+	"syscall"
 	"unsafe"
 )
 
 func ipv6ReceiveTrafficClass(fd int) (bool, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptReceiveTrafficClass, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptReceiveTrafficClass)
+	if err != nil {
 		return false, os.NewSyscallError("getsockopt", err)
 	}
 	return v == 1, nil
 }
 
 func setIPv6ReceiveTrafficClass(fd int, v bool) error {
-	vv := int32(boolint(v))
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptReceiveTrafficClass, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptReceiveTrafficClass, boolint(v)))
 }
 
 func ipv6ReceiveHopLimit(fd int) (bool, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptReceiveHopLimit, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptReceiveHopLimit)
+	if err != nil {
 		return false, os.NewSyscallError("getsockopt", err)
 	}
 	return v == 1, nil
 }
 
 func setIPv6ReceiveHopLimit(fd int, v bool) error {
-	vv := int32(boolint(v))
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptReceiveHopLimit, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptReceiveHopLimit, boolint(v)))
 }
 
 func ipv6ReceivePacketInfo(fd int) (bool, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptReceivePacketInfo, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptReceivePacketInfo)
+	if err != nil {
 		return false, os.NewSyscallError("getsockopt", err)
 	}
 	return v == 1, nil
 }
 
 func setIPv6ReceivePacketInfo(fd int, v bool) error {
-	vv := int32(boolint(v))
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptReceivePacketInfo, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptReceivePacketInfo, boolint(v)))
 }
 
 func ipv6PathMTU(fd int) (int, error) {
@@ -63,17 +58,15 @@ func ipv6PathMTU(fd int) (int, error) {
 }
 
 func ipv6ReceivePathMTU(fd int) (bool, error) {
-	var v int32
-	l := sysSockoptLen(4)
-	if err := getsockopt(fd, ianaProtocolIPv6, sysSockoptReceivePathMTU, unsafe.Pointer(&v), &l); err != nil {
+	v, err := syscall.GetsockoptInt(fd, ianaProtocolIPv6, sysSockoptReceivePathMTU)
+	if err != nil {
 		return false, os.NewSyscallError("getsockopt", err)
 	}
 	return v == 1, nil
 }
 
 func setIPv6ReceivePathMTU(fd int, v bool) error {
-	vv := int32(boolint(v))
-	return os.NewSyscallError("setsockopt", setsockopt(fd, ianaProtocolIPv6, sysSockoptReceivePathMTU, unsafe.Pointer(&vv), 4))
+	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, ianaProtocolIPv6, sysSockoptReceivePathMTU, boolint(v)))
 }
 
 func ipv6ICMPFilter(fd int) (*ICMPFilter, error) {

ipv6/sys_bsd.go

@@ -11,33 +11,22 @@ import (
 	"syscall"
 )
 
-// RFC 3493 options
-const (
-	// See /usr/include/netinet6/in6.h.
-	sysSockoptUnicastHopLimit    = 0x4
-	sysSockoptMulticastHopLimit  = 0xa
-	sysSockoptMulticastInterface = 0x9
-	sysSockoptMulticastLoopback  = 0xb
-	sysSockoptJoinGroup          = 0xc
-	sysSockoptLeaveGroup         = 0xd
-)
-
 // RFC 3542 options
 const (
 	// See /usr/include/netinet6/in6.h.
-	sysSockoptReceiveTrafficClass = 0x39
-	sysSockoptTrafficClass        = 0x3d
-	sysSockoptReceiveHopLimit     = 0x25
-	sysSockoptHopLimit            = 0x2f
-	sysSockoptReceivePacketInfo   = 0x24
-	sysSockoptPacketInfo          = 0x2e
-	sysSockoptReceivePathMTU      = 0x2b
-	sysSockoptPathMTU             = 0x2c
-	sysSockoptNextHop             = 0x30
-	sysSockoptChecksum            = 0x1a
+	sysSockoptReceiveTrafficClass = syscall.IPV6_RECVTCLASS
+	sysSockoptTrafficClass        = syscall.IPV6_TCLASS
+	sysSockoptReceiveHopLimit     = syscall.IPV6_RECVHOPLIMIT
+	sysSockoptHopLimit            = syscall.IPV6_HOPLIMIT
+	sysSockoptReceivePacketInfo   = syscall.IPV6_RECVPKTINFO
+	sysSockoptPacketInfo          = syscall.IPV6_PKTINFO
+	sysSockoptReceivePathMTU      = syscall.IPV6_RECVPATHMTU
+	sysSockoptPathMTU             = syscall.IPV6_PATHMTU
+	sysSockoptNextHop             = syscall.IPV6_NEXTHOP
+	sysSockoptChecksum            = syscall.IPV6_CHECKSUM
 
 	// See /usr/include/netinet6/in6.h.
-	sysSockoptICMPFilter = 0x12
+	sysSockoptICMPFilter = 0x12 // syscall.ICMP6_FILTER
 )
 
 func setSockaddr(sa *syscall.RawSockaddrInet6, ip net.IP, ifindex int) {

ipv6/sys_darwin.go

@@ -12,38 +12,27 @@ import (
 // RFC 2292 options
 const (
 	// See /usr/include/netinet6/in6.h.
-	sysSockopt2292HopLimit   = 0x14
-	sysSockopt2292PacketInfo = 0x13
-	sysSockopt2292NextHop    = 0x15
-)
-
-// RFC 3493 options
-const (
-	// See /usr/include/netinet6/in6.h.
-	sysSockoptUnicastHopLimit    = 0x4
-	sysSockoptMulticastHopLimit  = 0xa
-	sysSockoptMulticastInterface = 0x9
-	sysSockoptMulticastLoopback  = 0xb
-	sysSockoptJoinGroup          = 0xc
-	sysSockoptLeaveGroup         = 0xd
+	sysSockopt2292HopLimit   = syscall.IPV6_2292HOPLIMIT
+	sysSockopt2292PacketInfo = syscall.IPV6_2292PKTINFO
+	sysSockopt2292NextHop    = syscall.IPV6_2292NEXTHOP
 )
 
 // RFC 3542 options
 const (
 	// See /usr/include/netinet6/in6.h.
-	sysSockoptReceiveTrafficClass = 0x23
-	sysSockoptTrafficClass        = 0x24
-	sysSockoptReceiveHopLimit     = 0x25
-	sysSockoptHopLimit            = 0x2f
-	sysSockoptReceivePacketInfo   = 0x3d
-	sysSockoptPacketInfo          = 0x2e
-	sysSockoptReceivePathMTU      = 0x2b
-	sysSockoptPathMTU             = 0x2c
-	sysSockoptNextHop             = 0x30
-	sysSockoptChecksum            = 0x1a
+	sysSockoptReceiveTrafficClass = 0x23 // IPV6_RECVTCLASS
+	sysSockoptTrafficClass        = 0x24 // IPV6_TCLASS
+	sysSockoptReceiveHopLimit     = 0x25 // IPV6_RECVHOPLIMIT
+	sysSockoptHopLimit            = 0x2f // IPV6_HOPLIMIT
+	sysSockoptReceivePacketInfo   = 0x3d // IPV6_RECVPKTINFO
+	sysSockoptPacketInfo          = 0x2e // IPV6_PKTINFO
+	sysSockoptReceivePathMTU      = 0x2b // IPV6_RECVPATHMTU
+	sysSockoptPathMTU             = 0x2c // IPV6_PATHMTU
+	sysSockoptNextHop             = 0x30 // IPV6_NEXTHOP
+	sysSockoptChecksum            = 0x1a // IPV6_CHECKSUM
 
 	// See /usr/include/netinet6/in6.h.
-	sysSockoptICMPFilter = 0x12
+	sysSockoptICMPFilter = 0x12 // ICMP6_FILTER
 )
 
 func setSockaddr(sa *syscall.RawSockaddrInet6, ip net.IP, ifindex int) {

ipv6/sys_linux.go

@@ -9,33 +9,22 @@ import (
 	"syscall"
 )
 
-// RFC 3493 options
-const (
-	// See /usr/include/linux/in6.h.
-	sysSockoptUnicastHopLimit    = 0x10
-	sysSockoptMulticastHopLimit  = 0x12
-	sysSockoptMulticastInterface = 0x11
-	sysSockoptMulticastLoopback  = 0x13
-	sysSockoptJoinGroup          = 0x14
-	sysSockoptLeaveGroup         = 0x15
-)
-
 // RFC 3542 options
 const (
 	// See /usr/include/linux/ipv6.h,in6.h.
-	sysSockoptReceiveTrafficClass = 0x42
-	sysSockoptTrafficClass        = 0x43
-	sysSockoptReceiveHopLimit     = 0x33
-	sysSockoptHopLimit            = 0x34
-	sysSockoptReceivePacketInfo   = 0x31
-	sysSockoptPacketInfo          = 0x32
-	sysSockoptReceivePathMTU      = 0x3c
-	sysSockoptPathMTU             = 0x3d
-	sysSockoptNextHop             = 0x9
-	sysSockoptChecksum            = 0x7
+	sysSockoptReceiveTrafficClass = syscall.IPV6_RECVTCLASS
+	sysSockoptTrafficClass        = syscall.IPV6_TCLASS
+	sysSockoptReceiveHopLimit     = syscall.IPV6_RECVHOPLIMIT
+	sysSockoptHopLimit            = syscall.IPV6_HOPLIMIT
+	sysSockoptReceivePacketInfo   = syscall.IPV6_RECVPKTINFO
+	sysSockoptPacketInfo          = syscall.IPV6_PKTINFO
+	sysSockoptReceivePathMTU      = 0x3c // IPV6_RECVPATHMTU
+	sysSockoptPathMTU             = 0x3d // IPV6_PATHMTU
+	sysSockoptNextHop             = syscall.IPV6_NEXTHOP
+	sysSockoptChecksum            = syscall.IPV6_CHECKSUM
 
 	// See /usr/include/linux/icmpv6.h.
-	sysSockoptICMPFilter = 0x1
+	sysSockoptICMPFilter = 0x1 // syscall.ICMPV6_FILTER
 )
 
 func setSockaddr(sa *syscall.RawSockaddrInet6, ip net.IP, ifindex int) {

ipv6/sys_unix.go

@@ -8,6 +8,16 @@ package ipv6
 
 import "syscall"
 
+// RFC 3493 options
+const (
+	sysSockoptUnicastHopLimit    = syscall.IPV6_UNICAST_HOPS
+	sysSockoptMulticastHopLimit  = syscall.IPV6_MULTICAST_HOPS
+	sysSockoptMulticastInterface = syscall.IPV6_MULTICAST_IF
+	sysSockoptMulticastLoopback  = syscall.IPV6_MULTICAST_LOOP
+	sysSockoptJoinGroup          = syscall.IPV6_JOIN_GROUP
+	sysSockoptLeaveGroup         = syscall.IPV6_LEAVE_GROUP
+)
+
 const sysSizeofMTUInfo = 0x20
 
 type sysMTUInfo struct {

ipv6/sys_windows.go

@@ -12,18 +12,18 @@ import (
 // RFC 3493 options
 const (
 	// See ws2tcpip.h.
-	sysSockoptUnicastHopLimit    = 0x4
-	sysSockoptMulticastHopLimit  = 0xa
-	sysSockoptMulticastInterface = 0x9
-	sysSockoptMulticastLoopback  = 0xb
-	sysSockoptJoinGroup          = 0xc
-	sysSockoptLeaveGroup         = 0xd
+	sysSockoptUnicastHopLimit    = syscall.IPV6_UNICAST_HOPS
+	sysSockoptMulticastHopLimit  = syscall.IPV6_MULTICAST_HOPS
+	sysSockoptMulticastInterface = syscall.IPV6_MULTICAST_IF
+	sysSockoptMulticastLoopback  = syscall.IPV6_MULTICAST_LOOP
+	sysSockoptJoinGroup          = syscall.IPV6_JOIN_GROUP
+	sysSockoptLeaveGroup         = syscall.IPV6_LEAVE_GROUP
 )
 
 // RFC 3542 options
 const (
 	// See ws2tcpip.h.
-	sysSockoptPacketInfo = 0x13
+	sysSockoptPacketInfo = 0x13 // IPV6_PKTINFO
 )
 
 func setSockaddr(sa *syscall.RawSockaddrInet6, ip net.IP, ifindex int) {