static void dns_handler(int err, const struct dnshdr *hdr, struct list *ansl,
struct list *authl, struct list *addl, void *arg)
{
struct rst *rst = arg;
struct dnsrr *rr;
struct sa srv;
(void)err;
(void)hdr;
(void)authl;
(void)addl;
rr = dns_rrlist_find(ansl, rst->host, DNS_TYPE_A, DNS_CLASS_IN, true);
if (!rr) {
re_printf("rst: unable to resolve: %s\n", rst->host);
tmr_start(&rst->tmr, RETRY_WAIT, reconnect, rst);
return;
}
sa_set_in(&srv, rr->rdata.a.addr, rst->port);
err = tcp_connect(&rst->tc, &srv, estab_handler, recv_handler,
close_handler, rst);
if (err) {
re_printf("rst: tcp connect error: %m\n", err);
tmr_start(&rst->tmr, RETRY_WAIT, reconnect, rst);
return;
}
}
static void aaaa_handler(int err, const struct dnshdr *hdr, struct list *ansl,
struct list *authl, struct list *addl, void *arg)
{
struct stun_dns *dns = arg;
struct dnsrr *rr;
(void)hdr;
(void)authl;
(void)addl;
/* Find A answers */
rr = dns_rrlist_find(ansl, NULL, DNS_TYPE_AAAA, DNS_CLASS_IN, false);
if (!rr) {
err = err ? err : EDESTADDRREQ;
goto out;
}
sa_set_in6(&dns->srv, rr->rdata.aaaa.addr, sa_port(&dns->srv));
DEBUG_INFO("AAAA answer: %j\n", &dns->srv);
out:
resolved(dns, err);
}
static void srv_handler(int err, const struct dnshdr *hdr, struct list *ansl,
struct list *authl, struct list *addl, void *arg)
{
struct stun_dns *dns = arg;
struct dnsrr *rr, *arr;
(void)hdr;
(void)authl;
dns_rrlist_sort(ansl, DNS_TYPE_SRV);
/* Find SRV answers */
rr = dns_rrlist_find(ansl, NULL, DNS_TYPE_SRV, DNS_CLASS_IN, false);
if (!rr) {
DEBUG_INFO("no SRV entry, trying A lookup on \"%s\"\n",
dns->domain);
sa_set_in(&dns->srv, 0, dns->port);
err = a_or_aaaa_query(dns, dns->domain);
if (err)
goto out;
return;
}
DEBUG_INFO("SRV answer: %s:%u\n", rr->rdata.srv.target,
rr->rdata.srv.port);
/* Look for Additional information */
switch (dns->af) {
case AF_INET:
arr = dns_rrlist_find(addl, rr->rdata.srv.target,
DNS_TYPE_A, DNS_CLASS_IN, true);
if (arr) {
sa_set_in(&dns->srv, arr->rdata.a.addr,
rr->rdata.srv.port);
DEBUG_INFO("additional A: %j\n", &dns->srv);
goto out;
}
break;
#ifdef HAVE_INET6
case AF_INET6:
arr = dns_rrlist_find(addl, rr->rdata.srv.target,
DNS_TYPE_AAAA, DNS_CLASS_IN, true);
if (arr) {
sa_set_in6(&dns->srv, arr->rdata.aaaa.addr,
rr->rdata.srv.port);
DEBUG_INFO("additional AAAA: %j\n", &dns->srv);
goto out;
}
break;
#endif
}
sa_set_in(&dns->srv, 0, rr->rdata.srv.port);
err = a_or_aaaa_query(dns, rr->rdata.srv.target);
if (err) {
DEBUG_WARNING("SRV: A lookup failed (%m)\n", err);
goto out;
}
DEBUG_INFO("SRV handler: doing A/AAAA lookup..\n");
return;
out:
resolved(dns, err);
}
