int ipxitf_pprop (struct ipx_interface * intrfc, struct sk_buff * skb);
if its more than IPX_MAX_PPROP_HOPS hops or if it is smaller than a IPX header + the room for IPX_MAX_PPROP_HOPS hops we drop it, not even processing it locally, if it has exact IPX_MAX_PPROP_HOPS we don't broadcast it, but process it locally. See chapter 5 of Novell's ``IPX RIP and SAP Router Specification'', Part Number 107-000029-001.
If it is valid, check if we have pprop broadcasting enabled by the user, if not, just return zero for local processing.
If it is enabled check the packet and don't broadcast it if we have already seen this packet.
send it to the interfaces that aren't on the packet visited nets array, just after the IPX header.
Returns -EINVAL for invalid packets, so that the calling function drops the packet without local processing. 0 if packet is to be locally processed.