ip/dhcp6d: ignore short and from non-local source packets

This commit is contained in:
cinap_lenrek 2018-06-11 19:32:44 +02:00
parent 71402b2ea1
commit 232382bfc1

View file

@ -113,6 +113,21 @@ findifc(char *net, uchar ip[IPaddrlen])
return nil;
}
static Iplifc*
localonifc(Ipifc *ifc, uchar ip[IPaddrlen])
{
Iplifc *lifc;
uchar net[IPaddrlen];
for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){
maskip(ip, lifc->mask, net);
if(ipcmp(net, lifc->net) == 0)
return lifc;
}
return nil;
}
static int
openlisten(char *net)
{
@ -310,21 +325,27 @@ main(int argc, char *argv[])
break;
}
while((n = read(fd, ibuf, sizeof(ibuf))) > Udphdrsize+4){
r->req.p = ibuf+Udphdrsize;
r->req.e = ibuf+n;
while((n = read(fd, ibuf, sizeof(ibuf))) > 0){
if(n < Udphdrsize+4)
continue;
r->udp = (Udphdr*)ibuf;
if(isv4(r->udp->raddr))
continue;
if((r->ifc = findifc(netmtpt, r->udp->ifcaddr)) == nil)
continue;
if(localonifc(r->ifc, r->udp->raddr) == nil)
continue;
memmove(obuf, ibuf, Udphdrsize);
r->udp = (Udphdr*)obuf;
r->req.p = ibuf+Udphdrsize;
r->req.e = ibuf+n;
r->resp.p = obuf+Udphdrsize;
r->resp.e = &obuf[sizeof(obuf)];
r->tra = r->req.p[1]<<16 | r->req.p[2]<<8 | r->req.p[3];
r->req.t = r->req.p[0];
if((r->ifc = findifc(netmtpt, r->udp->ifcaddr)) == nil)
continue;
if(debug)
fprint(2, "%I->%I(%s) typ=%d tra=%x\n",
r->udp->raddr, r->udp->laddr, r->ifc->dev,