static int dns_module_check_timeout(eventer_t e, int mask, void *closure,
struct timeval *now) {
struct dns_check_info *ci;
ci = closure;
ci->timeout_event = NULL;
dns_check_log_results(ci);
__deactivate_ci(ci);
return 0;
}
static int dns_check_send(noit_module_t *self, noit_check_t *check,
noit_check_t *cause) {
void *vnv_pair = NULL;
struct dns_nameval *nv_pair;
eventer_t newe;
struct timeval p_int, now;
struct dns_check_info *ci = check->closure;
const char *config_val;
const char *rtype = NULL;
const char *nameserver = NULL;
int port = 0;
const char *port_str = NULL;
const char *want_sort = NULL;
const char *ctype = "IN";
const char *query = NULL;
char interpolated_nameserver[1024];
char interpolated_query[1024];
noit_hash_table check_attrs_hash = NOIT_HASH_EMPTY;
BAIL_ON_RUNNING_CHECK(check);
gettimeofday(&now, NULL);
memcpy(&check->last_fire_time, &now, sizeof(now));
ci->current.state = NP_BAD;
ci->current.available = NP_UNAVAILABLE;
ci->timed_out = 1;
ci->nrr = 0;
ci->sort = 1;
if(!strcmp(check->name, "in-addr.arpa") ||
(strlen(check->name) >= sizeof("::in-addr.arpa") - 1 &&
!strcmp(check->name + strlen(check->name) - sizeof("::in-addr.arpa") + 1,
"::in-addr.arpa"))) {
/* in-addr.arpa defaults:
* nameserver to NULL
* rtype to PTR
* query to %[:inaddrarpa:target]
*/
nameserver = NULL;
rtype = "PTR";
query = "%[:inaddrarpa:target_ip]";
}
else {
nameserver = "%[target_ip]";
rtype = "A";
query = "%[name]";
}
if(noit_hash_retr_str(check->config, "port", strlen("port"),
&port_str)) {
port = atoi(port_str);
}
#define CONFIG_OVERRIDE(a) \
if(noit_hash_retr_str(check->config, #a, strlen(#a), \
&config_val) && \
strlen(config_val) > 0) \
a = config_val
CONFIG_OVERRIDE(ctype);
CONFIG_OVERRIDE(nameserver);
CONFIG_OVERRIDE(rtype);
CONFIG_OVERRIDE(query);
CONFIG_OVERRIDE(want_sort);
if(nameserver && !strcmp(nameserver, "default")) nameserver = NULL;
if(want_sort && strcasecmp(want_sort, "on") && strcasecmp(want_sort, "true"))
ci->sort = 0;
noit_check_make_attrs(check, &check_attrs_hash);
if(nameserver) {
noit_check_interpolate(interpolated_nameserver,
sizeof(interpolated_nameserver),
nameserver,
&check_attrs_hash, check->config);
nameserver = interpolated_nameserver;
}
if(query) {
noit_check_interpolate(interpolated_query,
sizeof(interpolated_query),
query,
&check_attrs_hash, check->config);
query = interpolated_query;
}
noit_hash_destroy(&check_attrs_hash, NULL, NULL);
check->flags |= NP_RUNNING;
noitL(nldeb, "dns_check_send(%p,%s,%s,%s,%s,%s)\n",
self, check->target, nameserver ? nameserver : "default",
query ? query : "null", ctype, rtype);
__activate_ci(ci);
/* If this ci has a handle and it isn't the one we need,
* we should release it
*/
if(ci->h &&
((ci->h->ns == NULL && nameserver != NULL) ||
(ci->h->ns != NULL && nameserver == NULL) ||
(ci->h->ns && strcmp(ci->h->ns, nameserver)))) {
dns_ctx_release(ci->h);
ci->h = NULL;
}
/* use the cached one, unless we don't have one */
if(!ci->h) ci->h = dns_ctx_alloc(nameserver, port);
if(!ci->h) ci->error = strdup("bad nameserver");
/* Lookup out class */
if(!noit_hash_retrieve(&dns_ctypes, ctype, strlen(ctype),
&vnv_pair)) {
if(ci->error) free(ci->error);
ci->error = strdup("bad class");
}
else {
nv_pair = (struct dns_nameval *)vnv_pair;
ci->query_ctype = nv_pair->val;
}
/* Lookup out rr type */
if(!noit_hash_retrieve(&dns_rtypes, rtype, strlen(rtype),
&vnv_pair)) {
if(ci->error) free(ci->error);
ci->error = strdup("bad rr type");
}
else {
nv_pair = (struct dns_nameval *)vnv_pair;
ci->query_rtype = nv_pair->val;
}
if(!ci->error) {
/* Submit the query */
int abs;
if(!dns_ptodn(query, strlen(query), ci->dn, sizeof(ci->dn), &abs) ||
!dns_submit_dn(ci->h->ctx, ci->dn, ci->query_ctype, ci->query_rtype,
abs | DNS_NOSRCH, NULL, dns_cb, ci)) {
ci->error = strdup("submission error");
}
else {
dns_timeouts(ci->h->ctx, -1, now.tv_sec);
}
}
/* we could have completed by now... if so, we've nothing to do */
if(!__isactive_ci(ci)) return 0;
if(ci->error) {
/* Errors here are easy, fail and avoid scheduling a timeout */
ci->check->flags &= ~NP_RUNNING;
dns_check_log_results(ci);
__deactivate_ci(ci);
return 0;
}
newe = eventer_alloc();
newe->mask = EVENTER_TIMER;
gettimeofday(&now, NULL);
p_int.tv_sec = check->timeout / 1000;
p_int.tv_usec = (check->timeout % 1000) * 1000;
add_timeval(now, p_int, &newe->whence);
newe->closure = ci;
newe->callback = dns_check_timeout;
ci->timeout_event = newe;
eventer_add(newe);
return 0;
}
static void dns_cb(struct dns_ctx *ctx, void *result, void *data) {
int r = dns_status(ctx);
int len, i;
struct dns_check_info *ci = data;
struct dns_parse p;
struct dns_rr rr;
unsigned nrr;
unsigned char dn[DNS_MAXDN];
const unsigned char *pkt, *cur, *end;
char *result_str[MAX_RR] = { NULL };
char *result_combined = NULL;
/* If out ci isn't active, we must have timed out already */
if(!__isactive_ci(ci)) {
if(result) free(result);
return;
}
ci->timed_out = 0;
/* If we don't have a result, explode */
if (!result) {
ci->error = strdup(dns_strerror(r));
goto cleanup;
}
/* Process the packet */
pkt = result; end = pkt + r; cur = dns_payload(pkt);
dns_getdn(pkt, &cur, end, dn, sizeof(dn));
dns_initparse(&p, NULL, pkt, cur, end);
p.dnsp_qcls = 0;
p.dnsp_qtyp = 0;
nrr = 0;
while((r = dns_nextrr(&p, &rr)) > 0) {
if (!dns_dnequal(dn, rr.dnsrr_dn)) continue;
if ((ci->query_ctype == DNS_C_ANY || ci->query_ctype == rr.dnsrr_cls) &&
(ci->query_rtype == DNS_T_ANY || ci->query_rtype == rr.dnsrr_typ))
++nrr;
else if (rr.dnsrr_typ == DNS_T_CNAME && !nrr) {
if (dns_getdn(pkt, &rr.dnsrr_dptr, end,
p.dnsp_dnbuf, sizeof(p.dnsp_dnbuf)) <= 0 ||
rr.dnsrr_dptr != rr.dnsrr_dend) {
ci->error = strdup("protocol error");
break;
}
else {
int32_t on = 1;
/* This actually updates what we're looking for */
dns_dntodn(p.dnsp_dnbuf, ci->dn, sizeof(dn));
noit_stats_set_metric(ci->check, &ci->current, "cname", METRIC_INT32, &on);
/* Now follow the leader */
noitL(nldeb, "%s. CNAME %s.\n", dns_dntosp(dn),
dns_dntosp(p.dnsp_dnbuf));
dns_dntodn(p.dnsp_dnbuf, dn, sizeof(dn));
noitL(nldeb, " ---> '%s'\n", dns_dntosp(dn));
}
}
}
if (!r && !nrr) {
ci->error = strdup("no data");
}
dns_rewind(&p, NULL);
p.dnsp_qtyp = ci->query_rtype == DNS_T_ANY ? 0 : ci->query_rtype;
p.dnsp_qcls = ci->query_ctype == DNS_C_ANY ? 0 : ci->query_ctype;
while(dns_nextrr(&p, &rr) && ci->nrr < MAX_RR)
decode_rr(ci, &p, &rr, &result_str[ci->nrr]);
if(ci->sort)
qsort(result_str, ci->nrr, sizeof(*result_str), cstring_cmp);
/* calculate the length and allocate on the stack */
len = 0;
for(i=0; i<ci->nrr; i++) len += strlen(result_str[i]) + 2;
result_combined = alloca(len);
result_combined[0] = '\0';
/* string it together */
len = 0;
for(i=0; i<ci->nrr; i++) {
int slen;
if(i) { memcpy(result_combined + len, ", ", 2); len += 2; }
slen = strlen(result_str[i]);
memcpy(result_combined + len, result_str[i], slen);
len += slen;
result_combined[len] = '\0';
free(result_str[i]); /* free as we go */
}
noit_stats_set_metric(ci->check, &ci->current, "answer", METRIC_STRING, result_combined);
cleanup:
if(result) free(result);
if(ci->timeout_event) {
eventer_t e = eventer_remove(ci->timeout_event);
ci->timeout_event = NULL;
if(e) eventer_free(e);
}
ci->check->flags &= ~NP_RUNNING;
dns_check_log_results(ci);
__deactivate_ci(ci);
}