kuznet@ms2.inr.ac.ru writes:
> > of type ETH_P_ALL such that I intercept all packets.
>
> ptype is protocol multiplexor, rather than filter.
Sure. However, I think it should be possible for protocol handler to
modify the skb and tell net_rx_action() to reexamine it. That would make
stripping link-level headers easy. Currently we have to:
- call netif_rx to requeue skb (ie. in syncppp.c - this is bad), or
- requeue it in (link-level) protocol handler (unneded complication), or
- add IPv4/IPv6/IPX/whatever protocol dispatcher and call {ip,ipv6...}_rcv
routines from link-level proto handler (very bad, breaks code separation).
It would be, in my opinion, best for net_rx_action() to:
/* this calls all net taps - no pt_prev required */
for (ptype = ptype_all; ptype; ptype = ptype->next) {
if (!ptype->dev || ptype->dev == skb->dev) {
atomic_inc(&skb->users);
ptype->func(skb, ...); /* ignore return value */
/* func() is not allowed to alter skb */
}
}
/* Bridging code? */
/* this finds proto handler and passes skb to it, eventually
restarting when the handler asks */
restart:
type = skb->protocol;
for (ptype=ptype_base[ntohs(type)&15]; ptype; ptype=ptype->next) {
if (ptype->type == type &&
(!ptype->dev || ptype->dev == skb->dev)) {
atomic_inc(&skb->users);
switch (ptype->func(skb, ...)) {
case RCV_RESTART
goto restart;
case RCV_ACCEPTED; /* skb altered/destroyed */
goto end;
default: /* skb unaltered, try next handler */
}
}
end:
skb_free() if required;
Do we need to try another handler if previous one accepted the packet?
deliver_to_old_ones() should be dropped/fixed asap as well.
What do you think?
-- Krzysztof Halasa Network Administrator- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri Jun 16 2000 - 19:20:58 EDT