arp: Don't resolve own, configured IPv4 address

DHCP clients might try to resolve the assigned address to check if it's
already in use: don't resolve the configured IPv4 address.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
Stefano Brivio 2021-08-20 01:13:02 +02:00
parent 77c72b31ed
commit 64c0f20ab3

4
arp.c
View file

@ -63,6 +63,10 @@ int arp(struct ctx *c, struct ethhdr *eh, size_t len)
if (*((uint32_t *)&am->sip) && !memcmp(am->sip, am->tip, 4))
return 1;
/* Don't resolve our own address, either. */
if (!memcmp(am->tip, &c->addr4, 4))
return 1;
ah->ar_op = htons(ARPOP_REPLY);
memcpy(am->tha, am->sha, ETH_ALEN);
memcpy(am->sha, c->mac, ETH_ALEN);