_ (l3_type_not_ip4, "L3 type not IP4") \
_ (l3_src_address_not_local, "IP4 source address not local to subnet") \
_ (l3_dst_address_not_local, "IP4 destination address not local to subnet") \
+ _ (l3_dst_address_unset, "IP4 destination address is unset") \
_ (l3_src_address_is_local, "IP4 source address matches local interface") \
_ (l3_src_address_learned, "ARP request IP4 source address learned") \
_ (replies_received, "ARP replies received") \
(arp0->l3_type !=
clib_net_to_host_u16 (ETHERNET_TYPE_IP4) ?
ETHERNET_ARP_ERROR_l3_type_not_ip4 : error0);
+ error0 =
+ (0 == arp0->ip4_over_ethernet[0].ip4.as_u32 ?
+ ETHERNET_ARP_ERROR_l3_dst_address_unset : error0);
sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
}
}
- if (!(FIB_ENTRY_FLAG_CONNECTED & dst_flags))
+ if (fib_entry_is_sourced (dst_fei, FIB_SOURCE_ADJ))
+ {
+ /*
+ * We matched an adj-fib on ths source subnet (a /32 previously
+ * added as a result of ARP). If this request is a gratuitous
+ * ARP, then learn from it.
+ * The check for matching an adj-fib, is to prevent hosts
+ * from spamming us with gratuitous ARPS that might otherwise
+ * blow our ARP cache
+ */
+ if (arp0->ip4_over_ethernet[0].ip4.as_u32 ==
+ arp0->ip4_over_ethernet[1].ip4.as_u32)
+ error0 = arp_learn (vnm, am, sw_if_index0,
+ &arp0->ip4_over_ethernet[0]);
+ goto drop2;
+ }
+ else if (!(FIB_ENTRY_FLAG_CONNECTED & dst_flags))
{
error0 = ETHERNET_ARP_ERROR_l3_dst_address_not_local;
goto drop1;
/* Learn or update sender's mapping only for replies to addresses
* that are local to the subnet */
if (arp0->opcode ==
- clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_reply) &&
- dst_is_local0)
+ clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_reply))
{
- error0 = arp_learn (vnm, am, sw_if_index0,
- &arp0->ip4_over_ethernet[0]);
+ if (dst_is_local0)
+ error0 = arp_learn (vnm, am, sw_if_index0,
+ &arp0->ip4_over_ethernet[0]);
+ else
+ /* a reply for a non-local destination could be a GARP.
+ * GARPs for hosts we know were handled above, so this one
+ * we drop */
+ error0 = ETHERNET_ARP_ERROR_l3_dst_address_not_local;
+
goto drop1;
}
else if (arp0->opcode ==
continue;
drop1:
- if (0 == arp0->ip4_over_ethernet[0].ip4.as_u32 ||
- (arp0->ip4_over_ethernet[0].ip4.as_u32 ==
- arp0->ip4_over_ethernet[1].ip4.as_u32))
+ if (arp0->ip4_over_ethernet[0].ip4.as_u32 ==
+ arp0->ip4_over_ethernet[1].ip4.as_u32)
{
error0 = ETHERNET_ARP_ERROR_gratuitous_arp;
goto drop2;
}
void
-send_ip4_garp (vlib_main_t * vm, const vnet_hw_interface_t * hi)
+send_ip4_garp (vlib_main_t * vm, u32 sw_if_index)
{
ip4_main_t *i4m = &ip4_main;
- ip4_address_t *ip4_addr =
- ip4_interface_first_address (i4m, hi->sw_if_index, 0);
+ ip4_address_t *ip4_addr = ip4_interface_first_address (i4m, sw_if_index, 0);
- send_ip4_garp_w_addr (vm, ip4_addr, hi);
+ send_ip4_garp_w_addr (vm, ip4_addr, sw_if_index);
}
void
send_ip4_garp_w_addr (vlib_main_t * vm,
- const ip4_address_t * ip4_addr,
- const vnet_hw_interface_t * hi)
+ const ip4_address_t * ip4_addr, u32 sw_if_index)
{
ip4_main_t *i4m = &ip4_main;
- u32 sw_if_index = hi->sw_if_index;
+ vnet_main_t *vnm = vnet_get_main ();
+ u8 *rewrite, rewrite_len;
+ vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
if (ip4_addr)
{
/* Setup MAC header with ARP Etype and broadcast DMAC */
vlib_buffer_t *b = vlib_get_buffer (vm, bi);
- vlib_buffer_advance (b, -sizeof (ethernet_header_t));
+ rewrite =
+ ethernet_build_rewrite (vnm, sw_if_index, VNET_LINK_ARP,
+ VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST);
+ rewrite_len = vec_len (rewrite);
+ vlib_buffer_advance (b, -rewrite_len);
ethernet_header_t *e = vlib_buffer_get_current (b);
- e->type = clib_host_to_net_u16 (ETHERNET_TYPE_ARP);
- clib_memcpy (e->src_address, hi->hw_address, sizeof (e->src_address));
- memset (e->dst_address, 0xff, sizeof (e->dst_address));
+ clib_memcpy (e->dst_address, rewrite, rewrite_len);
+ vec_free (rewrite);
/* Send GARP packet out the specified interface */
vnet_buffer (b)->sw_if_index[VLIB_RX] =