udp: Actually use host resolver to forward DNS queries

Instead of the address of the first resolver we advertise to
the guest or namespace.

This was one of the intentions behind commit 3a2afde87d ("conf,
udp: Drop mostly duplicated dns_send arrays, rename related fields"),
but I forgot to implement this part. In practice, they are usually
the same thing, unless /etc/resolv.conf points to a loopback address.

Fixes: 3a2afde87d ("conf, udp: Drop mostly duplicated dns_send arrays, rename related fields")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Tested-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Stefano Brivio 2023-02-23 12:21:29 +00:00
parent 4ddbcb9c0c
commit ddf7097a71

4
udp.c
View file

@ -867,7 +867,7 @@ int udp_tap_handler(struct ctx *c, int af, const void *addr,
} else if (IN4_ARE_ADDR_EQUAL(&s_in.sin_addr,
&c->ip4.dns_match) &&
ntohs(s_in.sin_port) == 53) {
s_in.sin_addr = c->ip4.dns[0];
s_in.sin_addr = c->ip4.dns_host;
}
} else {
s_in6 = (struct sockaddr_in6) {
@ -890,7 +890,7 @@ int udp_tap_handler(struct ctx *c, int af, const void *addr,
s_in6.sin6_addr = c->ip6.addr_seen;
} else if (IN6_ARE_ADDR_EQUAL(addr, &c->ip6.dns_match) &&
ntohs(s_in6.sin6_port) == 53) {
s_in6.sin6_addr = c->ip6.dns[0];
s_in6.sin6_addr = c->ip6.dns_host;
} else if (IN6_IS_ADDR_LINKLOCAL(&s_in6.sin6_addr)) {
bind_addr = &c->ip6.addr_ll;
}