--- /dev/null
+// 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.
+
+// Netlink sockets and messages
+
+package syscall
+
+import (
+ "unsafe"
+)
+
+// Round the length of a netlink message up to align it properly.
+func nlmAlignOf(msglen int) int {
+ return (msglen + NLMSG_ALIGNTO - 1) & ^(NLMSG_ALIGNTO - 1)
+}
+
+// Round the length of a netlink route attribute up to align it
+// properly.
+func rtaAlignOf(attrlen int) int {
+ return (attrlen + RTA_ALIGNTO - 1) & ^(RTA_ALIGNTO - 1)
+}
+
+// NetlinkRouteRequest represents the request message to receive
+// routing and link states from the kernel.
+type NetlinkRouteRequest struct {
+ Header NlMsghdr
+ Data RtGenmsg
+}
+
+func (rr *NetlinkRouteRequest) toWireFormat() []byte {
+ b := make([]byte, rr.Header.Len)
+ b[0] = byte(rr.Header.Len)
+ b[1] = byte(rr.Header.Len >> 8)
+ b[2] = byte(rr.Header.Len >> 16)
+ b[3] = byte(rr.Header.Len >> 24)
+ b[4] = byte(rr.Header.Type)
+ b[5] = byte(rr.Header.Type >> 8)
+ b[6] = byte(rr.Header.Flags)
+ b[7] = byte(rr.Header.Flags >> 8)
+ b[8] = byte(rr.Header.Seq)
+ b[9] = byte(rr.Header.Seq >> 8)
+ b[10] = byte(rr.Header.Seq >> 16)
+ b[11] = byte(rr.Header.Seq >> 24)
+ b[12] = byte(rr.Header.Pid)
+ b[13] = byte(rr.Header.Pid >> 8)
+ b[14] = byte(rr.Header.Pid >> 16)
+ b[15] = byte(rr.Header.Pid >> 24)
+ b[16] = byte(rr.Data.Family)
+ return b
+}
+
+func newNetlinkRouteRequest(proto, seq, family int) []byte {
+ rr := &NetlinkRouteRequest{}
+ rr.Header.Len = NLMSG_HDRLEN + SizeofRtGenmsg
+ rr.Header.Type = uint16(proto)
+ rr.Header.Flags = NLM_F_DUMP | NLM_F_REQUEST
+ rr.Header.Seq = uint32(seq)
+ rr.Data.Family = uint8(family)
+ return rr.toWireFormat()
+}
+
+// NetlinkRIB returns routing information base, as known as RIB,
+// which consists of network facility information, states and
+// parameters.
+func NetlinkRIB(proto, family int) ([]byte, int) {
+ var (
+ s int
+ e int
+ lsanl SockaddrNetlink
+ seq int
+ tab []byte
+ )
+
+ s, e = Socket(AF_NETLINK, SOCK_RAW, 0)
+ if e != 0 {
+ return nil, e
+ }
+ defer Close(s)
+
+ lsanl.Family = AF_NETLINK
+ e = Bind(s, &lsanl)
+ if e != 0 {
+ return nil, e
+ }
+
+ seq++
+ wb := newNetlinkRouteRequest(proto, seq, family)
+ e = Sendto(s, wb, 0, &lsanl)
+ if e != 0 {
+ return nil, e
+ }
+
+ for {
+ var (
+ rb []byte
+ nr int
+ lsa Sockaddr
+ )
+
+ rb = make([]byte, Getpagesize())
+ nr, _, e = Recvfrom(s, rb, 0)
+ if e != 0 {
+ return nil, e
+ }
+ if nr < NLMSG_HDRLEN {
+ return nil, EINVAL
+ }
+ rb = rb[:nr]
+ tab = append(tab, rb...)
+
+ msgs, _ := ParseNetlinkMessage(rb)
+ for _, m := range msgs {
+ if lsa, e = Getsockname(s); e != 0 {
+ return nil, e
+ }
+ switch v := lsa.(type) {
+ case *SockaddrNetlink:
+ if m.Header.Seq != uint32(seq) || m.Header.Pid != v.Pid {
+ return nil, EINVAL
+ }
+ default:
+ return nil, EINVAL
+ }
+ if m.Header.Type == NLMSG_DONE {
+ goto done
+ }
+ if m.Header.Type == NLMSG_ERROR {
+ return nil, EINVAL
+ }
+ }
+ }
+
+done:
+ return tab, 0
+}
+
+// NetlinkMessage represents the netlink message.
+type NetlinkMessage struct {
+ Header NlMsghdr
+ Data []byte
+}
+
+// ParseNetlinkMessage parses buf as netlink messages and returns
+// the slice containing the NetlinkMessage structs.
+func ParseNetlinkMessage(buf []byte) ([]NetlinkMessage, int) {
+ var (
+ h *NlMsghdr
+ dbuf []byte
+ dlen int
+ e int
+ msgs []NetlinkMessage
+ )
+
+ for len(buf) >= NLMSG_HDRLEN {
+ h, dbuf, dlen, e = netlinkMessageHeaderAndData(buf)
+ if e != 0 {
+ break
+ }
+ m := NetlinkMessage{}
+ m.Header = *h
+ m.Data = dbuf[:h.Len-NLMSG_HDRLEN]
+ msgs = append(msgs, m)
+ buf = buf[dlen:]
+ }
+
+ return msgs, e
+}
+
+func netlinkMessageHeaderAndData(buf []byte) (*NlMsghdr, []byte, int, int) {
+ h := (*NlMsghdr)(unsafe.Pointer(&buf[0]))
+ if h.Len < NLMSG_HDRLEN || int(h.Len) > len(buf) {
+ return nil, nil, 0, EINVAL
+ }
+ return h, buf[NLMSG_HDRLEN:], nlmAlignOf(int(h.Len)), 0
+}
+
+// NetlinkRouteAttr represents the netlink route attribute.
+type NetlinkRouteAttr struct {
+ Attr RtAttr
+ Value []byte
+}
+
+// ParseNetlinkRouteAttr parses msg's payload as netlink route
+// attributes and returns the slice containing the NetlinkRouteAttr
+// structs.
+func ParseNetlinkRouteAttr(msg *NetlinkMessage) ([]NetlinkRouteAttr, int) {
+ var (
+ buf []byte
+ a *RtAttr
+ alen int
+ vbuf []byte
+ e int
+ attrs []NetlinkRouteAttr
+ )
+
+ switch msg.Header.Type {
+ case RTM_NEWLINK:
+ buf = msg.Data[SizeofIfInfomsg:]
+ case RTM_NEWADDR:
+ buf = msg.Data[SizeofIfAddrmsg:]
+ default:
+ return nil, EINVAL
+ }
+
+ for len(buf) >= SizeofRtAttr {
+ a, vbuf, alen, e = netlinkRouteAttrAndValue(buf)
+ if e != 0 {
+ break
+ }
+ ra := NetlinkRouteAttr{}
+ ra.Attr = *a
+ ra.Value = vbuf[:a.Len-SizeofRtAttr]
+ attrs = append(attrs, ra)
+ buf = buf[alen:]
+ }
+
+ return attrs, 0
+}
+
+func netlinkRouteAttrAndValue(buf []byte) (*RtAttr, []byte, int, int) {
+ h := (*RtAttr)(unsafe.Pointer(&buf[0]))
+ if h.Len < SizeofRtAttr || int(h.Len) > len(buf) {
+ return nil, nil, 0, EINVAL
+ }
+ return h, buf[SizeofRtAttr:], rtaAlignOf(int(h.Len)), 0
+}
$IFLA_NET_NS_PID = IFLA_NET_NS_PID,
$IFLA_IFALIAS = IFLA_IFALIAS,
$IFLA_MAX = IFLA_MAX,
+ $RT_SCOPE_UNIVERSE = RT_SCOPE_UNIVERSE,
+ $RT_SCOPE_SITE = RT_SCOPE_SITE,
+ $RT_SCOPE_LINK = RT_SCOPE_LINK,
+ $RT_SCOPE_HOST = RT_SCOPE_HOST,
+ $RT_SCOPE_NOWHERE = RT_SCOPE_NOWHERE,
+ $RT_TABLE_UNSPEC = RT_TABLE_UNSPEC,
+ $RT_TABLE_COMPAT = RT_TABLE_COMPAT,
+ $RT_TABLE_DEFAULT = RT_TABLE_DEFAULT,
+ $RT_TABLE_MAIN = RT_TABLE_MAIN,
+ $RT_TABLE_LOCAL = RT_TABLE_LOCAL,
+ $RT_TABLE_MAX = RT_TABLE_MAX,
+ $RTA_UNSPEC = RTA_UNSPEC,
+ $RTA_DST = RTA_DST,
+ $RTA_SRC = RTA_SRC,
+ $RTA_IIF = RTA_IIF,
+ $RTA_OIF = RTA_OIF,
+ $RTA_GATEWAY = RTA_GATEWAY,
+ $RTA_PRIORITY = RTA_PRIORITY,
+ $RTA_PREFSRC = RTA_PREFSRC,
+ $RTA_METRICS = RTA_METRICS,
+ $RTA_MULTIPATH = RTA_MULTIPATH,
+ $RTA_FLOW = RTA_FLOW,
+ $RTA_CACHEINFO = RTA_CACHEINFO,
+ $RTA_TABLE = RTA_TABLE,
+ $RTN_UNSPEC = RTN_UNSPEC,
+ $RTN_UNICAST = RTN_UNICAST,
+ $RTN_LOCAL = RTN_LOCAL,
+ $RTN_BROADCAST = RTN_BROADCAST,
+ $RTN_ANYCAST = RTN_ANYCAST,
+ $RTN_MULTICAST = RTN_MULTICAST,
+ $RTN_BLACKHOLE = RTN_BLACKHOLE,
+ $RTN_UNREACHABLE = RTN_UNREACHABLE,
+ $RTN_PROHIBIT = RTN_PROHIBIT,
+ $RTN_THROW = RTN_THROW,
+ $RTN_NAT = RTN_NAT,
+ $RTN_XRESOLVE = RTN_XRESOLVE,
$SizeofNlMsghdr = sizeof(struct nlmsghdr),
$SizeofNlMsgerr = sizeof(struct nlmsgerr),
$SizeofRtGenmsg = sizeof(struct rtgenmsg),
$SizeofIfInfomsg = sizeof(struct ifinfomsg),
$SizeofIfAddrmsg = sizeof(struct ifaddrmsg),
$SizeofRtmsg = sizeof(struct rtmsg),
+ $SizeofRtNexthop = sizeof(struct rtnexthop),
};
typedef struct nlmsghdr $NlMsghdr;
typedef struct ifinfomsg $IfInfomsg;
typedef struct ifaddrmsg $IfAddrmsg;
typedef struct rtmsg $RtMsg;
+typedef struct rtnexthop $RtNexthop;
// Inotify