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syscall, net: use native endianness for Linux netlink messages

Tested using 6g and gccgo on x86_64 GNU/Linux and using gccgo
on PowerPC GNU/Linux (which is big-endian).

R=golang-dev, bradfitz, mikioh.mikioh, iant
CC=golang-dev
https://golang.org/cl/5975073
This commit is contained in:
Ian Lance Taylor 2012-04-04 17:41:36 -07:00
parent 22690e6621
commit 35bc9d17df
2 changed files with 16 additions and 23 deletions

View File

@ -64,7 +64,7 @@ func newLink(ifim *syscall.IfInfomsg, attrs []syscall.NetlinkRouteAttr) Interfac
case syscall.IFLA_IFNAME:
ifi.Name = string(a.Value[:len(a.Value)-1])
case syscall.IFLA_MTU:
ifi.MTU = int(uint32(a.Value[3])<<24 | uint32(a.Value[2])<<16 | uint32(a.Value[1])<<8 | uint32(a.Value[0]))
ifi.MTU = int(*(*uint32)(unsafe.Pointer(&a.Value[:4][0])))
}
}
return ifi
@ -193,10 +193,14 @@ func parseProcNetIGMP(path string, ifi *Interface) []Addr {
name = f[1]
case len(f[0]) == 8:
if ifi == nil || name == ifi.Name {
// The Linux kernel puts the IP
// address in /proc/net/igmp in native
// endianness.
for i := 0; i+1 < len(f[0]); i += 2 {
b[i/2], _ = xtoi2(f[0][i:i+2], 0)
}
ifma := IPAddr{IP: IPv4(b[3], b[2], b[1], b[0])}
i := *(*uint32)(unsafe.Pointer(&b[:4][0]))
ifma := IPAddr{IP: IPv4(byte(i>>24), byte(i>>16), byte(i>>8), byte(i))}
ifmat = append(ifmat, ifma.toAddr())
}
}

View File

@ -30,29 +30,18 @@ type NetlinkRouteRequest struct {
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)
*(*uint32)(unsafe.Pointer(&b[0:4][0])) = rr.Header.Len
*(*uint16)(unsafe.Pointer(&b[4:6][0])) = rr.Header.Type
*(*uint16)(unsafe.Pointer(&b[6:8][0])) = rr.Header.Flags
*(*uint32)(unsafe.Pointer(&b[8:12][0])) = rr.Header.Seq
*(*uint32)(unsafe.Pointer(&b[12:16][0])) = rr.Header.Pid
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.Len = uint32(NLMSG_HDRLEN + SizeofRtGenmsg)
rr.Header.Type = uint16(proto)
rr.Header.Flags = NLM_F_DUMP | NLM_F_REQUEST
rr.Header.Seq = uint32(seq)
@ -156,7 +145,7 @@ func ParseNetlinkMessage(buf []byte) ([]NetlinkMessage, error) {
}
m := NetlinkMessage{}
m.Header = *h
m.Data = dbuf[:h.Len-NLMSG_HDRLEN]
m.Data = dbuf[:int(h.Len)-NLMSG_HDRLEN]
msgs = append(msgs, m)
buf = buf[dlen:]
}
@ -166,7 +155,7 @@ func ParseNetlinkMessage(buf []byte) ([]NetlinkMessage, error) {
func netlinkMessageHeaderAndData(buf []byte) (*NlMsghdr, []byte, int, error) {
h := (*NlMsghdr)(unsafe.Pointer(&buf[0]))
if h.Len < NLMSG_HDRLEN || int(h.Len) > len(buf) {
if int(h.Len) < NLMSG_HDRLEN || int(h.Len) > len(buf) {
return nil, nil, 0, EINVAL
}
return h, buf[NLMSG_HDRLEN:], nlmAlignOf(int(h.Len)), nil
@ -209,7 +198,7 @@ func ParseNetlinkRouteAttr(msg *NetlinkMessage) ([]NetlinkRouteAttr, error) {
}
ra := NetlinkRouteAttr{}
ra.Attr = *a
ra.Value = vbuf[:a.Len-SizeofRtAttr]
ra.Value = vbuf[:int(a.Len)-SizeofRtAttr]
attrs = append(attrs, ra)
buf = buf[alen:]
}
@ -219,7 +208,7 @@ func ParseNetlinkRouteAttr(msg *NetlinkMessage) ([]NetlinkRouteAttr, error) {
func netlinkRouteAttrAndValue(buf []byte) (*RtAttr, []byte, int, error) {
h := (*RtAttr)(unsafe.Pointer(&buf[0]))
if h.Len < SizeofRtAttr || int(h.Len) > len(buf) {
if int(h.Len) < SizeofRtAttr || int(h.Len) > len(buf) {
return nil, nil, 0, EINVAL
}
return h, buf[SizeofRtAttr:], rtaAlignOf(int(h.Len)), nil