syscall: update routing message support for BSD variants

R=rsc
CC=golang-dev
https://golang.org/cl/4826056

14 files changed, 244 insertions, 69 deletions

diff --git a/src/pkg/syscall/Makefile b/src/pkg/syscall/Makefile
index fa0fe8ba9f..f626d09987 100644
--- a/src/pkg/syscall/Makefile
+++ b/src/pkg/syscall/Makefile
@@ -20,6 +20,7 @@ GOFILES_freebsd=\
 	bpf_bsd.go\
 	exec_unix.go\
 	route_bsd.go\
+	route_freebsd.go\
 	sockcmsg_unix.go\
 	syscall_bsd.go\
 	syscall_unix.go\
@@ -28,6 +29,7 @@ GOFILES_darwin=\
 	bpf_bsd.go\
 	exec_unix.go\
 	route_bsd.go\
+	route_darwin.go\
 	sockcmsg_unix.go\
 	syscall_bsd.go\
 	syscall_unix.go\
diff --git a/src/pkg/syscall/route_bsd.go b/src/pkg/syscall/route_bsd.go
index 7821a6d29b..e41667c140 100644
--- a/src/pkg/syscall/route_bsd.go
+++ b/src/pkg/syscall/route_bsd.go
@@ -65,32 +65,6 @@ type anyMessage struct {
 	Type    uint8
 }
 
-func (any *anyMessage) toRoutingMessage(buf []byte) RoutingMessage {
-	switch any.Type {
-	case RTM_ADD, RTM_DELETE, RTM_CHANGE, RTM_GET, RTM_LOSING, RTM_REDIRECT, RTM_MISS, RTM_LOCK, RTM_RESOLVE:
-		p := (*RouteMessage)(unsafe.Pointer(any))
-		rtm := &RouteMessage{}
-		rtm.Header = p.Header
-		rtm.Data = buf[SizeofRtMsghdr:any.Msglen]
-		return rtm
-	case RTM_IFINFO:
-		p := (*InterfaceMessage)(unsafe.Pointer(any))
-		ifm := &InterfaceMessage{}
-		ifm.Header = p.Header
-		ifm.Data = buf[SizeofIfMsghdr:any.Msglen]
-		return ifm
-	case RTM_NEWADDR, RTM_DELADDR:
-		p := (*InterfaceAddrMessage)(unsafe.Pointer(any))
-		ifam := &InterfaceAddrMessage{}
-		ifam.Header = p.Header
-		ifam.Data = buf[SizeofIfaMsghdr:any.Msglen]
-		return ifam
-	case RTM_NEWMADDR, RTM_DELMADDR:
-		// TODO: implement this in the near future
-	}
-	return nil
-}
-
 // RouteMessage represents a routing message containing routing
 // entries.
 type RouteMessage struct {
@@ -128,16 +102,16 @@ type InterfaceAddrMessage struct {
 	Data   []byte
 }
 
-const rtaMask = RTA_IFA | RTA_NETMASK | RTA_BRD
+const rtaIfaMask = RTA_IFA | RTA_NETMASK | RTA_BRD
 
 func (m *InterfaceAddrMessage) sockaddr() (sas []Sockaddr) {
-	if m.Header.Addrs&rtaMask == 0 {
+	if m.Header.Addrs&rtaIfaMask == 0 {
 		return nil
 	}
 
 	buf := m.Data[:]
 	for i := uint(0); i < RTAX_MAX; i++ {
-		if m.Header.Addrs&rtaMask&(1<<i) == 0 {
+		if m.Header.Addrs&rtaIfaMask&(1<<i) == 0 {
 			continue
 		}
 		rsa := (*RawSockaddr)(unsafe.Pointer(&buf[0]))
@@ -157,6 +131,35 @@ func (m *InterfaceAddrMessage) sockaddr() (sas []Sockaddr) {
 	return sas
 }
 
+const rtaIfmaMask = RTA_GATEWAY | RTA_IFP | RTA_IFA
+
+func (m *InterfaceMulticastAddrMessage) sockaddr() (sas []Sockaddr) {
+	if m.Header.Addrs&rtaIfmaMask == 0 {
+		return nil
+	}
+
+	buf := m.Data[:]
+	for i := uint(0); i < RTAX_MAX; i++ {
+		if m.Header.Addrs&rtaIfmaMask&(1<<i) == 0 {
+			continue
+		}
+		rsa := (*RawSockaddr)(unsafe.Pointer(&buf[0]))
+		switch i {
+		case RTAX_IFA:
+			sa, e := anyToSockaddr((*RawSockaddrAny)(unsafe.Pointer(rsa)))
+			if e != 0 {
+				return nil
+			}
+			sas = append(sas, sa)
+		case RTAX_GATEWAY, RTAX_IFP:
+			// nothing to do
+		}
+		buf = buf[rsaAlignOf(int(rsa.Len)):]
+	}
+
+	return sas
+}
+
 // ParseRoutingMessage parses buf as routing messages and returns
 // the slice containing the RoutingMessage interfaces.
 func ParseRoutingMessage(buf []byte) (msgs []RoutingMessage, errno int) {
diff --git a/src/pkg/syscall/route_darwin.go b/src/pkg/syscall/route_darwin.go
new file mode 100644
index 0000000000..8f79b708d6
--- /dev/null
+++ b/src/pkg/syscall/route_darwin.go
@@ -0,0 +1,48 @@
+// Copyright 2011 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.
+
+// Routing sockets and messages for Darwin
+
+package syscall
+
+import (
+	"unsafe"
+)
+
+func (any *anyMessage) toRoutingMessage(buf []byte) RoutingMessage {
+	switch any.Type {
+	case RTM_ADD, RTM_DELETE, RTM_CHANGE, RTM_GET, RTM_LOSING, RTM_REDIRECT, RTM_MISS, RTM_LOCK, RTM_RESOLVE:
+		p := (*RouteMessage)(unsafe.Pointer(any))
+		rtm := &RouteMessage{}
+		rtm.Header = p.Header
+		rtm.Data = buf[SizeofRtMsghdr:any.Msglen]
+		return rtm
+	case RTM_IFINFO:
+		p := (*InterfaceMessage)(unsafe.Pointer(any))
+		ifm := &InterfaceMessage{}
+		ifm.Header = p.Header
+		ifm.Data = buf[SizeofIfMsghdr:any.Msglen]
+		return ifm
+	case RTM_NEWADDR, RTM_DELADDR:
+		p := (*InterfaceAddrMessage)(unsafe.Pointer(any))
+		ifam := &InterfaceAddrMessage{}
+		ifam.Header = p.Header
+		ifam.Data = buf[SizeofIfaMsghdr:any.Msglen]
+		return ifam
+	case RTM_NEWMADDR2, RTM_DELMADDR:
+		p := (*InterfaceMulticastAddrMessage)(unsafe.Pointer(any))
+		ifmam := &InterfaceMulticastAddrMessage{}
+		ifmam.Header = p.Header
+		ifmam.Data = buf[SizeofIfmaMsghdr2:any.Msglen]
+		return ifmam
+	}
+	return nil
+}
+
+// InterfaceMulticastAddrMessage represents a routing message
+// containing network interface address entries.
+type InterfaceMulticastAddrMessage struct {
+	Header IfmaMsghdr2
+	Data   []byte
+}
diff --git a/src/pkg/syscall/route_freebsd.go b/src/pkg/syscall/route_freebsd.go
new file mode 100644
index 0000000000..128e93cf90
--- /dev/null
+++ b/src/pkg/syscall/route_freebsd.go
@@ -0,0 +1,48 @@
+// Copyright 2011 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.
+
+// Routing sockets and messages for FreeBSD
+
+package syscall
+
+import (
+	"unsafe"
+)
+
+func (any *anyMessage) toRoutingMessage(buf []byte) RoutingMessage {
+	switch any.Type {
+	case RTM_ADD, RTM_DELETE, RTM_CHANGE, RTM_GET, RTM_LOSING, RTM_REDIRECT, RTM_MISS, RTM_LOCK, RTM_RESOLVE:
+		p := (*RouteMessage)(unsafe.Pointer(any))
+		rtm := &RouteMessage{}
+		rtm.Header = p.Header
+		rtm.Data = buf[SizeofRtMsghdr:any.Msglen]
+		return rtm
+	case RTM_IFINFO:
+		p := (*InterfaceMessage)(unsafe.Pointer(any))
+		ifm := &InterfaceMessage{}
+		ifm.Header = p.Header
+		ifm.Data = buf[SizeofIfMsghdr:any.Msglen]
+		return ifm
+	case RTM_NEWADDR, RTM_DELADDR:
+		p := (*InterfaceAddrMessage)(unsafe.Pointer(any))
+		ifam := &InterfaceAddrMessage{}
+		ifam.Header = p.Header
+		ifam.Data = buf[SizeofIfaMsghdr:any.Msglen]
+		return ifam
+	case RTM_NEWMADDR, RTM_DELMADDR:
+		p := (*InterfaceMulticastAddrMessage)(unsafe.Pointer(any))
+		ifmam := &InterfaceMulticastAddrMessage{}
+		ifmam.Header = p.Header
+		ifmam.Data = buf[SizeofIfmaMsghdr:any.Msglen]
+		return ifmam
+	}
+	return nil
+}
+
+// InterfaceMulticastAddrMessage represents a routing message
+// containing network interface address entries.
+type InterfaceMulticastAddrMessage struct {
+	Header IfmaMsghdr
+	Data   []byte
+}
diff --git a/src/pkg/syscall/types_darwin.c b/src/pkg/syscall/types_darwin.c
index ecccd5bd92..730d7f7b66 100644
--- a/src/pkg/syscall/types_darwin.c
+++ b/src/pkg/syscall/types_darwin.c
@@ -149,6 +149,8 @@ enum {
 	$SizeofIfMsghdr = sizeof(struct if_msghdr),
 	$SizeofIfData = sizeof(struct if_data),
 	$SizeofIfaMsghdr = sizeof(struct ifa_msghdr),
+	$SizeofIfmaMsghdr = sizeof(struct ifma_msghdr),
+	$SizeofIfmaMsghdr2 = sizeof(struct ifma_msghdr2),
 	$SizeofRtMsghdr = sizeof(struct rt_msghdr),
 	$SizeofRtMetrics = sizeof(struct rt_metrics),
 };
@@ -156,6 +158,8 @@ enum {
 typedef struct if_msghdr $IfMsghdr;
 typedef struct if_data $IfData;
 typedef struct ifa_msghdr $IfaMsghdr;
+typedef struct ifma_msghdr $IfmaMsghdr;
+typedef struct ifma_msghdr2 $IfmaMsghdr2;
 typedef struct rt_msghdr $RtMsghdr;
 typedef struct rt_metrics $RtMetrics;
 
diff --git a/src/pkg/syscall/types_freebsd.c b/src/pkg/syscall/types_freebsd.c
index 97636550ac..1494661cfe 100644
--- a/src/pkg/syscall/types_freebsd.c
+++ b/src/pkg/syscall/types_freebsd.c
@@ -157,6 +157,7 @@ enum {
 	$SizeofIfMsghdr = sizeof(struct if_msghdr),
 	$SizeofIfData = sizeof(struct if_data),
 	$SizeofIfaMsghdr = sizeof(struct ifa_msghdr),
+	$SizeofIfmaMsghdr = sizeof(struct ifma_msghdr),
 	$SizeofRtMsghdr = sizeof(struct rt_msghdr),
 	$SizeofRtMetrics = sizeof(struct rt_metrics),
 };
@@ -164,6 +165,7 @@ enum {
 typedef struct if_msghdr $IfMsghdr;
 typedef struct if_data $IfData;
 typedef struct ifa_msghdr $IfaMsghdr;
+typedef struct ifma_msghdr $IfmaMsghdr;
 typedef struct rt_msghdr $RtMsghdr;
 typedef struct rt_metrics $RtMetrics;
 
diff --git a/src/pkg/syscall/zsyscall_darwin_386.go b/src/pkg/syscall/zsyscall_darwin_386.go
index 436953ecaa..6d7c3da8a9 100644
--- a/src/pkg/syscall/zsyscall_darwin_386.go
+++ b/src/pkg/syscall/zsyscall_darwin_386.go
@@ -33,16 +33,6 @@ func wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe() (r int, w int, errno int) {
-	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
-	r = int(r0)
-	w = int(r1)
-	errno = int(e1)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, errno int) {
 	r0, _, e1 := Syscall(SYS_ACCEPT, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
 	fd = int(r0)
@@ -244,6 +234,16 @@ func ptrace(request int, pid int, addr uintptr, data uintptr) (errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func pipe() (r int, w int, errno int) {
+	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
+	r = int(r0)
+	w = int(r1)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func kill(pid int, signum int, posix int) (errno int) {
 	_, _, e1 := Syscall(SYS_KILL, uintptr(pid), uintptr(signum), uintptr(posix))
 	errno = int(e1)
diff --git a/src/pkg/syscall/zsyscall_darwin_amd64.go b/src/pkg/syscall/zsyscall_darwin_amd64.go
index 1ba4c3cfe5..25d8772862 100644
--- a/src/pkg/syscall/zsyscall_darwin_amd64.go
+++ b/src/pkg/syscall/zsyscall_darwin_amd64.go
@@ -33,16 +33,6 @@ func wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe() (r int, w int, errno int) {
-	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
-	r = int(r0)
-	w = int(r1)
-	errno = int(e1)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, errno int) {
 	r0, _, e1 := Syscall(SYS_ACCEPT, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
 	fd = int(r0)
@@ -244,6 +234,16 @@ func ptrace(request int, pid int, addr uintptr, data uintptr) (errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func pipe() (r int, w int, errno int) {
+	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
+	r = int(r0)
+	w = int(r1)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func kill(pid int, signum int, posix int) (errno int) {
 	_, _, e1 := Syscall(SYS_KILL, uintptr(pid), uintptr(signum), uintptr(posix))
 	errno = int(e1)
diff --git a/src/pkg/syscall/zsyscall_freebsd_386.go b/src/pkg/syscall/zsyscall_freebsd_386.go
index d152e43806..03c19ff651 100644
--- a/src/pkg/syscall/zsyscall_freebsd_386.go
+++ b/src/pkg/syscall/zsyscall_freebsd_386.go
@@ -33,16 +33,6 @@ func wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe() (r int, w int, errno int) {
-	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
-	r = int(r0)
-	w = int(r1)
-	errno = int(e1)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, errno int) {
 	r0, _, e1 := Syscall(SYS_ACCEPT, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
 	fd = int(r0)
@@ -236,6 +226,16 @@ func munmap(addr uintptr, length uintptr) (errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func pipe() (r int, w int, errno int) {
+	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
+	r = int(r0)
+	w = int(r1)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Access(path string, mode uint32) (errno int) {
 	_, _, e1 := Syscall(SYS_ACCESS, uintptr(unsafe.Pointer(StringBytePtr(path))), uintptr(mode), 0)
 	errno = int(e1)
diff --git a/src/pkg/syscall/zsyscall_freebsd_amd64.go b/src/pkg/syscall/zsyscall_freebsd_amd64.go
index 156b087e39..756c200af9 100644
--- a/src/pkg/syscall/zsyscall_freebsd_amd64.go
+++ b/src/pkg/syscall/zsyscall_freebsd_amd64.go
@@ -33,16 +33,6 @@ func wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe() (r int, w int, errno int) {
-	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
-	r = int(r0)
-	w = int(r1)
-	errno = int(e1)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, errno int) {
 	r0, _, e1 := Syscall(SYS_ACCEPT, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
 	fd = int(r0)
@@ -236,6 +226,16 @@ func munmap(addr uintptr, length uintptr) (errno int) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func pipe() (r int, w int, errno int) {
+	r0, r1, e1 := RawSyscall(SYS_PIPE, 0, 0, 0)
+	r = int(r0)
+	w = int(r1)
+	errno = int(e1)
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Access(path string, mode uint32) (errno int) {
 	_, _, e1 := Syscall(SYS_ACCESS, uintptr(unsafe.Pointer(StringBytePtr(path))), uintptr(mode), 0)
 	errno = int(e1)
diff --git a/src/pkg/syscall/ztypes_darwin_386.go b/src/pkg/syscall/ztypes_darwin_386.go
index ba6e590c4f..0ec74f3792 100644
--- a/src/pkg/syscall/ztypes_darwin_386.go
+++ b/src/pkg/syscall/ztypes_darwin_386.go
@@ -29,6 +29,8 @@ const (
 	SizeofIfMsghdr         = 0x70
 	SizeofIfData           = 0x60
 	SizeofIfaMsghdr        = 0x14
+	SizeofIfmaMsghdr       = 0x10
+	SizeofIfmaMsghdr2      = 0x14
 	SizeofRtMsghdr         = 0x5c
 	SizeofRtMetrics        = 0x38
 	SizeofBpfVersion       = 0x4
@@ -322,6 +324,27 @@ type IfaMsghdr struct {
 	Metric       int32
 }
 
+type IfmaMsghdr struct {
+	Msglen       uint16
+	Version      uint8
+	Type         uint8
+	Addrs        int32
+	Flags        int32
+	Index        uint16
+	Pad_godefs_0 [2]byte
+}
+
+type IfmaMsghdr2 struct {
+	Msglen       uint16
+	Version      uint8
+	Type         uint8
+	Addrs        int32
+	Flags        int32
+	Index        uint16
+	Pad_godefs_0 [2]byte
+	Refcount     int32
+}
+
 type RtMsghdr struct {
 	Msglen       uint16
 	Version      uint8
diff --git a/src/pkg/syscall/ztypes_darwin_amd64.go b/src/pkg/syscall/ztypes_darwin_amd64.go
index 59c832812b..f0e8a92489 100644
--- a/src/pkg/syscall/ztypes_darwin_amd64.go
+++ b/src/pkg/syscall/ztypes_darwin_amd64.go
@@ -29,6 +29,8 @@ const (
 	SizeofIfMsghdr         = 0x70
 	SizeofIfData           = 0x60
 	SizeofIfaMsghdr        = 0x14
+	SizeofIfmaMsghdr       = 0x10
+	SizeofIfmaMsghdr2      = 0x14
 	SizeofRtMsghdr         = 0x5c
 	SizeofRtMetrics        = 0x38
 	SizeofBpfVersion       = 0x4
@@ -332,6 +334,27 @@ type IfaMsghdr struct {
 	Metric       int32
 }
 
+type IfmaMsghdr struct {
+	Msglen       uint16
+	Version      uint8
+	Type         uint8
+	Addrs        int32
+	Flags        int32
+	Index        uint16
+	Pad_godefs_0 [2]byte
+}
+
+type IfmaMsghdr2 struct {
+	Msglen       uint16
+	Version      uint8
+	Type         uint8
+	Addrs        int32
+	Flags        int32
+	Index        uint16
+	Pad_godefs_0 [2]byte
+	Refcount     int32
+}
+
 type RtMsghdr struct {
 	Msglen       uint16
 	Version      uint8
diff --git a/src/pkg/syscall/ztypes_freebsd_386.go b/src/pkg/syscall/ztypes_freebsd_386.go
index 6304d3b813..01cf2fbda7 100644
--- a/src/pkg/syscall/ztypes_freebsd_386.go
+++ b/src/pkg/syscall/ztypes_freebsd_386.go
@@ -43,6 +43,7 @@ const (
 	SizeofIfMsghdr         = 0x60
 	SizeofIfData           = 0x50
 	SizeofIfaMsghdr        = 0x14
+	SizeofIfmaMsghdr       = 0x10
 	SizeofRtMsghdr         = 0x5c
 	SizeofRtMetrics        = 0x38
 	SizeofBpfVersion       = 0x4
@@ -315,6 +316,16 @@ type IfaMsghdr struct {
 	Metric       int32
 }
 
+type IfmaMsghdr struct {
+	Msglen       uint16
+	Version      uint8
+	Type         uint8
+	Addrs        int32
+	Flags        int32
+	Index        uint16
+	Pad_godefs_0 [2]byte
+}
+
 type RtMsghdr struct {
 	Msglen       uint16
 	Version      uint8
diff --git a/src/pkg/syscall/ztypes_freebsd_amd64.go b/src/pkg/syscall/ztypes_freebsd_amd64.go
index ef5a51c4d8..d6a05ae68a 100644
--- a/src/pkg/syscall/ztypes_freebsd_amd64.go
+++ b/src/pkg/syscall/ztypes_freebsd_amd64.go
@@ -43,6 +43,7 @@ const (
 	SizeofIfMsghdr         = 0xa8
 	SizeofIfData           = 0x98
 	SizeofIfaMsghdr        = 0x14
+	SizeofIfmaMsghdr       = 0x10
 	SizeofRtMsghdr         = 0x98
 	SizeofRtMetrics        = 0x70
 	SizeofBpfVersion       = 0x4
@@ -318,6 +319,16 @@ type IfaMsghdr struct {
 	Metric       int32
 }
 
+type IfmaMsghdr struct {
+	Msglen       uint16
+	Version      uint8
+	Type         uint8
+	Addrs        int32
+	Flags        int32
+	Index        uint16
+	Pad_godefs_0 [2]byte
+}
+
 type RtMsghdr struct {
 	Msglen       uint16
 	Version      uint8