ldns_resolver* createResolver(const char *dnsserver) {
ldns_resolver *res = NULL;
ldns_status status;
ldns_rdf *ns_rdf;
if (dnsserver) {
// Use the given DNS server
res = ldns_resolver_new();
if (!res)
return NULL;
// Create rdf from dnsserver
ns_rdf = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A, dnsserver);
#ifdef USE_IPV6
if (!ns_rdf)
ns_rdf = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA, dnsserver);
#endif
if (!ns_rdf) {
ldns_resolver_deep_free(res);
return NULL;
} else {
status = ldns_resolver_push_nameserver(res, ns_rdf);
ldns_rdf_deep_free(ns_rdf);
if (status != LDNS_STATUS_OK) {
ldns_resolver_free(res);
return NULL;
}
}
} else {
// Use a DNS server from resolv.conf
status = ldns_resolver_new_frm_file(&res, NULL);
if (status != LDNS_STATUS_OK) {
ldns_resolver_free(res);
return NULL;
}
}
// Enable TCP if requested
ldns_resolver_set_usevc(res, mp_ldns_usevc);
return res;
}
/* same naive method as in drill0.9
* We resolver _ALL_ the names, which is ofcourse not needed
* We _do_ use the local resolver to do that, so it still is
* fast, but it can be made to run much faster
*/
ldns_pkt *
do_trace(ldns_resolver *local_res, ldns_rdf *name, ldns_rr_type t,
ldns_rr_class c)
{
ldns_resolver *res;
ldns_pkt *p;
ldns_rr_list *new_nss_a;
ldns_rr_list *new_nss_aaaa;
ldns_rr_list *final_answer;
ldns_rr_list *new_nss;
ldns_rr_list *ns_addr;
uint16_t loop_count;
ldns_rdf *pop;
ldns_status status;
size_t i;
loop_count = 0;
new_nss_a = NULL;
new_nss_aaaa = NULL;
new_nss = NULL;
ns_addr = NULL;
final_answer = NULL;
p = ldns_pkt_new();
res = ldns_resolver_new();
if (!p) {
if (res) {
ldns_resolver_free(res);
}
error("Memory allocation failed");
return NULL;
}
if (!res) {
ldns_pkt_free(p);
error("Memory allocation failed");
return NULL;
}
/* transfer some properties of local_res to res,
* because they were given on the commandline */
ldns_resolver_set_ip6(res,
ldns_resolver_ip6(local_res));
ldns_resolver_set_port(res,
ldns_resolver_port(local_res));
ldns_resolver_set_debug(res,
ldns_resolver_debug(local_res));
ldns_resolver_set_dnssec(res,
ldns_resolver_dnssec(local_res));
ldns_resolver_set_fail(res,
ldns_resolver_fail(local_res));
ldns_resolver_set_usevc(res,
ldns_resolver_usevc(local_res));
ldns_resolver_set_random(res,
ldns_resolver_random(local_res));
ldns_resolver_set_recursive(res, false);
/* setup the root nameserver in the new resolver */
status = ldns_resolver_push_nameserver_rr_list(res, global_dns_root);
if (status != LDNS_STATUS_OK) {
fprintf(stderr, "Error adding root servers to resolver: %s\n", ldns_get_errorstr_by_id(status));
ldns_rr_list_print(stdout, global_dns_root);
ldns_resolver_free(res);
ldns_pkt_free(p);
return NULL;
}
/* this must be a real query to local_res */
status = ldns_resolver_send(&p, res, ldns_dname_new_frm_str("."), LDNS_RR_TYPE_NS, c, 0);
/* p can still be NULL */
if (ldns_pkt_empty(p)) {
warning("No root server information received");
}
if (status == LDNS_STATUS_OK) {
if (!ldns_pkt_empty(p)) {
drill_pkt_print(stdout, local_res, p);
}
} else {
error("cannot use local resolver");
return NULL;
}
status = ldns_resolver_send(&p, res, name, t, c, 0);
while(status == LDNS_STATUS_OK &&
ldns_pkt_reply_type(p) == LDNS_PACKET_REFERRAL) {
if (!p) {
/* some error occurred, bail out */
return NULL;
}
new_nss_a = ldns_pkt_rr_list_by_type(p,
LDNS_RR_TYPE_A, LDNS_SECTION_ADDITIONAL);
new_nss_aaaa = ldns_pkt_rr_list_by_type(p,
LDNS_RR_TYPE_AAAA, LDNS_SECTION_ADDITIONAL);
new_nss = ldns_pkt_rr_list_by_type(p,
LDNS_RR_TYPE_NS, LDNS_SECTION_AUTHORITY);
if (verbosity != -1) {
ldns_rr_list_print(stdout, new_nss);
}
/* checks itself for verbosity */
drill_pkt_print_footer(stdout, local_res, p);
/* remove the old nameserver from the resolver */
while(ldns_resolver_pop_nameserver(res)) { /* do it */ }
/* also check for new_nss emptyness */
if (!new_nss_aaaa && !new_nss_a) {
/*
* no nameserver found!!!
* try to resolve the names we do got
*/
for(i = 0; i < ldns_rr_list_rr_count(new_nss); i++) {
/* get the name of the nameserver */
pop = ldns_rr_rdf(ldns_rr_list_rr(new_nss, i), 0);
if (!pop) {
break;
}
ldns_rr_list_print(stdout, new_nss);
ldns_rdf_print(stdout, pop);
/* retrieve it's addresses */
ns_addr = ldns_rr_list_cat_clone(ns_addr,
ldns_get_rr_list_addr_by_name(local_res, pop, c, 0));
}
if (ns_addr) {
if (ldns_resolver_push_nameserver_rr_list(res, ns_addr) !=
LDNS_STATUS_OK) {
error("Error adding new nameservers");
ldns_pkt_free(p);
return NULL;
}
ldns_rr_list_free(ns_addr);
} else {
ldns_rr_list_print(stdout, ns_addr);
error("Could not find the nameserver ip addr; abort");
ldns_pkt_free(p);
return NULL;
}
}
/* add the new ones */
if (new_nss_aaaa) {
if (ldns_resolver_push_nameserver_rr_list(res, new_nss_aaaa) !=
LDNS_STATUS_OK) {
error("adding new nameservers");
ldns_pkt_free(p);
return NULL;
}
}
if (new_nss_a) {
if (ldns_resolver_push_nameserver_rr_list(res, new_nss_a) !=
LDNS_STATUS_OK) {
error("adding new nameservers");
ldns_pkt_free(p);
return NULL;
}
}
if (loop_count++ > 20) {
/* unlikely that we are doing something usefull */
error("Looks like we are looping");
ldns_pkt_free(p);
return NULL;
}
status = ldns_resolver_send(&p, res, name, t, c, 0);
new_nss_aaaa = NULL;
new_nss_a = NULL;
ns_addr = NULL;
}
status = ldns_resolver_send(&p, res, name, t, c, 0);
if (!p) {
return NULL;
}
new_nss = ldns_pkt_authority(p);
final_answer = ldns_pkt_answer(p);
if (verbosity != -1) {
ldns_rr_list_print(stdout, final_answer);
ldns_rr_list_print(stdout, new_nss);
}
drill_pkt_print_footer(stdout, local_res, p);
ldns_pkt_free(p);
return NULL;
}
int main(int argc, char **argv) {
/* Local Vars */
int i;
int soa_valid = 0;
int ns_valid = 0;
ldns_rdf *rd_domain;
ldns_rdf *rd_trace;
ldns_rdf *rd_cdomain;
ldns_pkt *pkt;
ldns_resolver *res;
ldns_rr *rr;
ldns_rr_list *rrl;
ldns_rr_list *rrl_domain_soa;
ldns_rr_list *rrl_domain_soa_rrsig;
ldns_rr_list *rrl_domain_ns;
ldns_rr_list *rrl_domain_ns_rrsig;
ldns_rr_list *rrl_valid_keys;
ldns_status status;
/* Set signal handling and alarm */
if (signal(SIGALRM, timeout_alarm_handler) == SIG_ERR)
critical("Setup SIGALRM trap failed!");
/* Process check arguments */
if (process_arguments(argc, argv) != OK)
unknown("Parsing arguments failed!");
/* Start plugin timeout */
alarm(mp_timeout);
rd_domain = ldns_dname_new_frm_str(domainname);
if (!rd_domain)
unknown("Illegal domain name");
rd_trace = ldns_dname_new_frm_str(domaintrace);
if (!rd_trace)
unknown("Illegal trace domain name");
/* Check domain is subdomain from trace start */
if (!ldns_dname_is_subdomain(rd_domain, rd_trace)) {
ldns_rr_list_deep_free(trusted_keys);
ldns_rdf_deep_free(rd_domain);
ldns_rdf_deep_free(rd_trace);
unknown("'%s' is not a subdomain of '%s'.", domainname,
domaintrace);
}
/* Add trusted keys for trace domain to rrl_valid_keys. */
rrl_valid_keys = ldns_rr_list_new();
for(i = 0; i < ldns_rr_list_rr_count(trusted_keys); i++) {
rr = ldns_rr_list_rr(trusted_keys, i);
if (ldns_dname_compare(ldns_rr_owner(rr),rd_trace) == 0)
ldns_rr_list_push_rr(rrl_valid_keys, ldns_rr_clone(rr));
}
ldns_rr_list_deep_free(trusted_keys);
if (ldns_rr_list_rr_count(rrl_valid_keys) == 0) {
ldns_rdf_deep_free(rd_domain);
ldns_rdf_deep_free(rd_trace);
ldns_rr_list_deep_free(rrl_valid_keys);
critical("No trusted key for trace start '%s'", domaintrace?domaintrace:".");
}
if (mp_verbose >= 2) {
printf("--[ Trusted keys used ]-------------------------------------\n");
ldns_rr_list_sort(rrl_valid_keys);
ldns_rr_list_print(stdout, rrl_valid_keys);
printf("------------------------------------------------------------\n");
}
/* create a new resolver with dns_server or server from /etc/resolv.conf */
res = createResolver(hostname);
if (!res) {
ldns_rdf_deep_free(rd_domain);
ldns_rdf_deep_free(rd_trace);
ldns_rr_list_deep_free(rrl_valid_keys);
unknown("Creating resolver failed.");
}
resolverEnableDnssec(res);
ldns_resolver_set_dnssec_anchors(res, rrl_valid_keys);
/* check domain exists */
pkt = mp_ldns_resolver_query(res, rd_domain, LDNS_RR_TYPE_SOA,
LDNS_RR_CLASS_IN, LDNS_RD);
if (pkt == NULL || ldns_pkt_get_rcode(pkt) != LDNS_RCODE_NOERROR) {
ldns_rdf_deep_free(rd_domain);
ldns_rdf_deep_free(rd_trace);
ldns_resolver_deep_free(res);
if (pkt && ldns_pkt_get_rcode(pkt) == LDNS_RCODE_NXDOMAIN) {
ldns_pkt_free(pkt);
critical("Domain '%s' don't exist.", domainname);
}
ldns_pkt_free(pkt);
critical("Unable to get SOA for %s.", domainname);
}
rrl_domain_soa = ldns_pkt_rr_list_by_name_and_type(pkt, rd_domain,
LDNS_RR_TYPE_SOA,
LDNS_SECTION_ANSWER);
if (rrl_domain_soa == NULL || ldns_rr_list_rr_count(rrl_domain_soa) == 0) {
ldns_rdf_deep_free(rd_domain);
ldns_rdf_deep_free(rd_trace);
ldns_resolver_deep_free(res);
ldns_pkt_free(pkt);
critical("Domain '%s' not found.", domainname);
}
rrl_domain_soa_rrsig = ldns_dnssec_pkt_get_rrsigs_for_name_and_type(pkt,
rd_domain, LDNS_RR_TYPE_SOA);
if (rrl_domain_soa_rrsig == NULL ||
ldns_rr_list_rr_count(rrl_domain_soa_rrsig) == 0) {
free(domaintrace);
ldns_rdf_deep_free(rd_domain);
ldns_rdf_deep_free(rd_trace);
ldns_resolver_deep_free(res);
ldns_pkt_free(pkt);
ldns_rr_list_deep_free(rrl_domain_soa);
critical("Domain '%s' not signed.", domainname);
}
ldns_pkt_free(pkt);
pkt = ldns_resolver_query(res, rd_domain, LDNS_RR_TYPE_NS,
LDNS_RR_CLASS_IN, LDNS_RD);
rrl_domain_ns = ldns_pkt_rr_list_by_name_and_type(pkt, rd_domain,
LDNS_RR_TYPE_NS,
LDNS_SECTION_ANSWER);
rrl_domain_ns_rrsig = ldns_dnssec_pkt_get_rrsigs_for_name_and_type(pkt,
rd_domain,
LDNS_RR_TYPE_NS);
ldns_pkt_free(pkt);
if (mp_verbose >= 2) {
printf("--[ Checked Domain ]----------------------------------------\n");
ldns_rr_list_print(stdout, rrl_domain_soa);
printf("------------------------------------------------------------\n");
ldns_rr_list_print(stdout, rrl_domain_soa_rrsig);
printf("------------------------------------------------------------\n");
ldns_rr_list_print(stdout, rrl_domain_ns);
printf("------------------------------------------------------------\n");
ldns_rr_list_print(stdout, rrl_domain_ns_rrsig);
printf("------------------------------------------------------------\n");
}
/* create a new resolver with dns_server or server from /etc/resolv.conf */
ldns_resolver_free(res);
res = createResolver(resolver);
if (!res) {
ldns_rdf_deep_free(rd_domain);
ldns_rdf_deep_free(rd_trace);
ldns_rr_list_deep_free(rrl_valid_keys);
unknown("Creating resolver failed.");
}
resolverEnableDnssec(res);
ldns_resolver_set_dnssec_anchors(res, rrl_valid_keys);
/* Fetch valid keys from top down */
i = ldns_dname_label_count(rd_domain) - ldns_dname_label_count(rd_trace);
for (; i>=0; i--) {
rd_cdomain = ldns_dname_clone_from(rd_domain, i);
if (mp_verbose) {
char *str = ldns_rdf2str(rd_cdomain);
printf("Trace: %s\n", str);
free(str);
}
rrl = ldns_fetch_valid_domain_keys(res, rd_cdomain, rrl_valid_keys, &status);
if (mp_verbose >= 2) {
printf("--[ Valid Keys ]----------------------------------------\n");
ldns_rr_list_sort(rrl);
ldns_rr_list_print(stdout, rrl);
printf("------------------------------------------------------------\n");
}
ldns_rr_list_cat(rrl_valid_keys, rrl);
ldns_rr_list_free(rrl);
ldns_rdf_deep_free(rd_cdomain);
}
ldns_rdf_deep_free(rd_trace);
ldns_rdf_deep_free(rd_domain);
/* Validate SOA */
for(i = 0; i < ldns_rr_list_rr_count(rrl_domain_soa_rrsig); i++) {
rr = ldns_rr_list_rr(rrl_domain_soa_rrsig, i);
status = ldns_verify_rrsig_keylist(rrl_domain_soa, rr, rrl_valid_keys, NULL);
if (status == LDNS_STATUS_OK)
soa_valid++;
else if (mp_verbose > 0)
fprintf(stderr, "ldns_verify_rrsig_keylist SOA failed: %s\n",
ldns_get_errorstr_by_id(status));
}
ldns_rr_list_deep_free(rrl_domain_soa);
ldns_rr_list_deep_free(rrl_domain_soa_rrsig);
if (soa_valid == 0) {
critical("No valid Signatur for SOA of '%s'", domainname);
free(domainname);
free(domaintrace);
ldns_resolver_deep_free(res);
ldns_rr_list_deep_free(rrl_domain_ns);
ldns_rr_list_deep_free(rrl_domain_ns_rrsig);
return checkState;
}
/* Validate NS */
for(i = 0; i < ldns_rr_list_rr_count(rrl_domain_ns_rrsig); i++) {
rr = ldns_rr_list_rr(rrl_domain_ns_rrsig, i);
status = ldns_verify_rrsig_keylist(rrl_domain_ns, rr, rrl_valid_keys, NULL);
if (status == LDNS_STATUS_OK)
ns_valid++;
else if (mp_verbose > 0)
fprintf(stderr, "ldns_verify_rrsig_keylist NS failed: %s\n",
ldns_get_errorstr_by_id(status));
}
ldns_rr_list_deep_free(rrl_domain_ns);
ldns_rr_list_deep_free(rrl_domain_ns_rrsig);
ldns_resolver_deep_free(res);
if (ns_valid == 0) {
critical("No valid Signatur for NS of '%s'", domainname);
free(domainname);
free(domaintrace);
return checkState;
}
ok("Trust for '%s' successfull traces from '%s'", domainname,
domaintrace);
free(domainname);
free(domaintrace);
return checkState;
}
