syscall: add netlink support for linux/386, linux/amd64, linux/arm

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/4535078

1 files changed, 26 insertions, 1 deletions

diff --git a/src/pkg/syscall/syscall_linux.go b/src/pkg/syscall/syscall_linux.go
index 4a3797c20c..cd040530e7 100644
--- a/src/pkg/syscall/syscall_linux.go
+++ b/src/pkg/syscall/syscall_linux.go
@@ -290,8 +290,33 @@ func (sa *SockaddrLinklayer) sockaddr() (uintptr, _Socklen, int) {
 	return uintptr(unsafe.Pointer(&sa.raw)), SizeofSockaddrLinklayer, 0
 }
 
+type SockaddrNetlink struct {
+	Family uint16
+	Pad    uint16
+	Pid    uint32
+	Groups uint32
+	raw    RawSockaddrNetlink
+}
+
+func (sa *SockaddrNetlink) sockaddr() (uintptr, _Socklen, int) {
+	sa.raw.Family = AF_NETLINK
+	sa.raw.Pad = sa.Pad
+	sa.raw.Pid = sa.Pid
+	sa.raw.Groups = sa.Groups
+	return uintptr(unsafe.Pointer(&sa.raw)), SizeofSockaddrNetlink, 0
+}
+
 func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, int) {
 	switch rsa.Addr.Family {
+	case AF_NETLINK:
+		pp := (*RawSockaddrNetlink)(unsafe.Pointer(rsa))
+		sa := new(SockaddrNetlink)
+		sa.Family = pp.Family
+		sa.Pad = pp.Pad
+		sa.Pid = pp.Pid
+		sa.Groups = pp.Groups
+		return sa, 0
+
 	case AF_PACKET:
 		pp := (*RawSockaddrLinklayer)(unsafe.Pointer(rsa))
 		sa := new(SockaddrLinklayer)
@@ -489,7 +514,7 @@ func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from
 	oobn = int(msg.Controllen)
 	recvflags = int(msg.Flags)
 	// source address is only specified if the socket is unconnected
-	if rsa.Addr.Family != 0 {
+	if rsa.Addr.Family != AF_UNSPEC {
 		from, errno = anyToSockaddr(&rsa)
 	}
 	return