[lwip-devel] etharp.c updating

[Leon Woestenberg]

Hello,

etharp.c version 1.162: "Fixed ARP input processing: only add a new
entry if a request was directed as us (RFC 826, Packet Reception),
otherwise only update existing entries; internalized some functions"

changes:

etharp_ip_input(struct netif *netif, struct pbuf *p)
<...>
  update_arp_entry(netif, &(iphdr->src), &(ethhdr->src), 0);

to:

etharp_ip_input(struct netif *netif, struct pbuf *p)
<...>
  update_arp_entry(netif, &(iphdr->src), &(ethhdr->src), ETHARP_FIND_ONLY);

However, I think the former behaviour (update on any ARP) was correct:

         "As specified in [36], any node receiving any ARP packet (Request
         or Reply) MUST update its local ARP cache with the Sender
         Protocol and Hardware Addresses in the ARP packet, if the
         receiving node has an entry for that IP address already in its
         ARP cache.  This requirement in the ARP protocol applies even
         for ARP Request packets, and for ARP Reply packets that do not
         match any ARP Request transmitted by the receiving node [36]"

   [36]  Plummer, D., "Ethernet Address Resolution Protocol: Or
         converting network protocol addresses to 48.bit Ethernet
         address for transmission on Ethernet hardware", STD 37, RFC
         826, November 1982.


Regards,
-- 
Leon