4 * resolver implementation
6 * a Net::DNS like library for C
8 * (c) NLnet Labs, 2004-2006
10 * See the file LICENSE for the license
13 #include <ldns/config.h>
15 #include <ldns/ldns.h>
18 /* Access function for reading
19 * and setting the different Resolver
24 ldns_resolver_port(const ldns_resolver *r)
30 ldns_resolver_edns_udp_size(const ldns_resolver *r)
32 return r->_edns_udp_size;
36 ldns_resolver_retry(const ldns_resolver *r)
42 ldns_resolver_retrans(const ldns_resolver *r)
48 ldns_resolver_fallback(const ldns_resolver *r)
54 ldns_resolver_ip6(const ldns_resolver *r)
60 ldns_resolver_recursive(const ldns_resolver *r)
66 ldns_resolver_debug(const ldns_resolver *r)
72 ldns_resolver_dnsrch(const ldns_resolver *r)
78 ldns_resolver_fail(const ldns_resolver *r)
84 ldns_resolver_defnames(const ldns_resolver *r)
90 ldns_resolver_domain(const ldns_resolver *r)
96 ldns_resolver_searchlist(const ldns_resolver *r)
98 return r->_searchlist;
102 ldns_resolver_nameservers(const ldns_resolver *r)
104 return r->_nameservers;
108 ldns_resolver_nameserver_count(const ldns_resolver *r)
110 return r->_nameserver_count;
114 ldns_resolver_dnssec(const ldns_resolver *r)
120 ldns_resolver_dnssec_cd(const ldns_resolver *r)
122 return r->_dnssec_cd;
126 ldns_resolver_dnssec_anchors(const ldns_resolver *r)
128 return r->_dnssec_anchors;
132 ldns_resolver_trusted_key(const ldns_resolver *r, ldns_rr_list * keys, ldns_rr_list * trusted_keys)
137 ldns_rr_list * trust_anchors;
140 if (!r || !keys) { return false; }
142 trust_anchors = ldns_resolver_dnssec_anchors(r);
144 if (!trust_anchors) { return false; }
146 for (i = 0; i < ldns_rr_list_rr_count(keys); i++) {
148 cur_rr = ldns_rr_list_rr(keys, i);
149 if (ldns_rr_list_contains_rr(trust_anchors, cur_rr)) {
150 if (trusted_keys) { ldns_rr_list_push_rr(trusted_keys, cur_rr); }
159 ldns_resolver_igntc(const ldns_resolver *r)
165 ldns_resolver_usevc(const ldns_resolver *r)
171 ldns_resolver_rtt(const ldns_resolver *r)
177 ldns_resolver_nameserver_rtt(const ldns_resolver *r, size_t pos)
183 rtt = ldns_resolver_rtt(r);
185 if (pos >= ldns_resolver_nameserver_count(r)) {
195 ldns_resolver_timeout(const ldns_resolver *r)
201 ldns_resolver_tsig_keyname(const ldns_resolver *r)
203 return r->_tsig_keyname;
207 ldns_resolver_tsig_algorithm(const ldns_resolver *r)
209 return r->_tsig_algorithm;
213 ldns_resolver_tsig_keydata(const ldns_resolver *r)
215 return r->_tsig_keydata;
219 ldns_resolver_random(const ldns_resolver *r)
225 ldns_resolver_searchlist_count(const ldns_resolver *r)
227 return r->_searchlist_count;
232 ldns_resolver_set_port(ldns_resolver *r, uint16_t p)
238 ldns_resolver_pop_nameserver(ldns_resolver *r)
240 ldns_rdf **nameservers;
247 ns_count = ldns_resolver_nameserver_count(r);
248 nameservers = ldns_resolver_nameservers(r);
249 rtt = ldns_resolver_rtt(r);
250 if (ns_count == 0 || !nameservers) {
254 pop = nameservers[ns_count - 1];
256 nameservers = LDNS_XREALLOC(nameservers, ldns_rdf *, (ns_count - 1));
257 rtt = LDNS_XREALLOC(rtt, size_t, (ns_count - 1));
260 ldns_resolver_set_nameservers(r, nameservers);
262 ldns_resolver_set_rtt(r, rtt);
264 ldns_resolver_dec_nameserver_count(r);
269 ldns_resolver_push_nameserver(ldns_resolver *r, ldns_rdf *n)
271 ldns_rdf **nameservers;
275 if (ldns_rdf_get_type(n) != LDNS_RDF_TYPE_A &&
276 ldns_rdf_get_type(n) != LDNS_RDF_TYPE_AAAA) {
277 return LDNS_STATUS_ERR;
280 ns_count = ldns_resolver_nameserver_count(r);
281 nameservers = ldns_resolver_nameservers(r);
282 rtt = ldns_resolver_rtt(r);
284 /* make room for the next one */
286 nameservers = LDNS_XMALLOC(ldns_rdf *, 1);
288 nameservers = LDNS_XREALLOC(nameservers, ldns_rdf *, (ns_count + 1));
291 return LDNS_STATUS_MEM_ERR;
293 /* set the new value in the resolver */
294 ldns_resolver_set_nameservers(r, nameservers);
296 /* don't forget the rtt */
298 rtt = LDNS_XMALLOC(size_t, 1);
300 rtt = LDNS_XREALLOC(rtt, size_t, (ns_count + 1));
303 return LDNS_STATUS_MEM_ERR;
305 /* slide n in its slot. */
306 /* we clone it here, because then we can free the original
307 * rr's where it stood */
308 nameservers[ns_count] = ldns_rdf_clone(n);
309 rtt[ns_count] = LDNS_RESOLV_RTT_MIN;
310 ldns_resolver_incr_nameserver_count(r);
311 ldns_resolver_set_rtt(r, rtt);
312 return LDNS_STATUS_OK;
316 ldns_resolver_push_nameserver_rr(ldns_resolver *r, ldns_rr *rr)
319 if ((!rr) || (ldns_rr_get_type(rr) != LDNS_RR_TYPE_A &&
320 ldns_rr_get_type(rr) != LDNS_RR_TYPE_AAAA)) {
321 return LDNS_STATUS_ERR;
323 address = ldns_rr_rdf(rr, 0); /* extract the ip number */
325 return ldns_resolver_push_nameserver(r, address);
327 return LDNS_STATUS_ERR;
332 ldns_resolver_push_nameserver_rr_list(ldns_resolver *r, ldns_rr_list *rrlist)
338 stat = LDNS_STATUS_OK;
340 for(i = 0; i < ldns_rr_list_rr_count(rrlist); i++) {
341 rr = ldns_rr_list_rr(rrlist, i);
342 if (ldns_resolver_push_nameserver_rr(r, rr) != LDNS_STATUS_OK) {
343 stat = LDNS_STATUS_ERR;
349 return LDNS_STATUS_ERR;
354 ldns_resolver_set_edns_udp_size(ldns_resolver *r, uint16_t s)
356 r->_edns_udp_size = s;
360 ldns_resolver_set_recursive(ldns_resolver *r, bool re)
366 ldns_resolver_set_dnssec(ldns_resolver *r, bool d)
372 ldns_resolver_set_dnssec_cd(ldns_resolver *r, bool d)
378 ldns_resolver_set_dnssec_anchors(ldns_resolver *r, ldns_rr_list * l)
380 r->_dnssec_anchors = l;
384 ldns_resolver_push_dnssec_anchor(ldns_resolver *r, ldns_rr *rr)
386 ldns_rr_list * trust_anchors;
388 if ((!rr) || (ldns_rr_get_type(rr) != LDNS_RR_TYPE_DNSKEY)) {
389 return LDNS_STATUS_ERR;
392 if (!(trust_anchors = ldns_resolver_dnssec_anchors(r))) { /* Initialize */
393 trust_anchors = ldns_rr_list_new();
394 ldns_resolver_set_dnssec_anchors(r, trust_anchors);
397 return (ldns_rr_list_push_rr(trust_anchors, ldns_rr_clone(rr))) ? LDNS_STATUS_OK : LDNS_STATUS_ERR;
401 ldns_resolver_set_igntc(ldns_resolver *r, bool i)
407 ldns_resolver_set_usevc(ldns_resolver *r, bool vc)
413 ldns_resolver_set_debug(ldns_resolver *r, bool d)
419 ldns_resolver_set_ip6(ldns_resolver *r, uint8_t ip6)
425 ldns_resolver_set_fail(ldns_resolver *r, bool f)
431 ldns_resolver_set_searchlist_count(ldns_resolver *r, size_t c)
433 r->_searchlist_count = c;
437 ldns_resolver_set_nameserver_count(ldns_resolver *r, size_t c)
439 r->_nameserver_count = c;
443 ldns_resolver_set_dnsrch(ldns_resolver *r, bool d)
449 ldns_resolver_set_retry(ldns_resolver *r, uint8_t retry)
455 ldns_resolver_set_retrans(ldns_resolver *r, uint8_t retrans)
457 r->_retrans = retrans;
461 ldns_resolver_set_fallback(ldns_resolver *r, bool fallback)
463 r->_fallback = fallback;
467 ldns_resolver_set_nameservers(ldns_resolver *r, ldns_rdf **n)
473 ldns_resolver_set_defnames(ldns_resolver *r, bool d)
479 ldns_resolver_set_rtt(ldns_resolver *r, size_t *rtt)
485 ldns_resolver_set_nameserver_rtt(ldns_resolver *r, size_t pos, size_t value)
491 rtt = ldns_resolver_rtt(r);
493 if (pos >= ldns_resolver_nameserver_count(r)) {
502 ldns_resolver_incr_nameserver_count(ldns_resolver *r)
506 c = ldns_resolver_nameserver_count(r);
507 ldns_resolver_set_nameserver_count(r, ++c);
511 ldns_resolver_dec_nameserver_count(ldns_resolver *r)
515 c = ldns_resolver_nameserver_count(r);
519 ldns_resolver_set_nameserver_count(r, --c);
524 ldns_resolver_set_domain(ldns_resolver *r, ldns_rdf *d)
530 ldns_resolver_set_timeout(ldns_resolver *r, struct timeval timeout)
532 r->_timeout.tv_sec = timeout.tv_sec;
533 r->_timeout.tv_usec = timeout.tv_usec;
537 ldns_resolver_push_searchlist(ldns_resolver *r, ldns_rdf *d)
539 ldns_rdf **searchlist;
542 if (ldns_rdf_get_type(d) != LDNS_RDF_TYPE_DNAME) {
546 list_count = ldns_resolver_searchlist_count(r);
547 searchlist = ldns_resolver_searchlist(r);
549 searchlist = LDNS_XREALLOC(searchlist, ldns_rdf *, (list_count + 1));
551 r->_searchlist = searchlist;
553 searchlist[list_count] = ldns_rdf_clone(d);
554 ldns_resolver_set_searchlist_count(r, list_count + 1);
555 } /* no way to report mem err */
559 ldns_resolver_set_tsig_keyname(ldns_resolver *r, char *tsig_keyname)
561 LDNS_FREE(r->_tsig_keyname);
562 r->_tsig_keyname = strdup(tsig_keyname);
566 ldns_resolver_set_tsig_algorithm(ldns_resolver *r, char *tsig_algorithm)
568 LDNS_FREE(r->_tsig_algorithm);
569 r->_tsig_algorithm = strdup(tsig_algorithm);
573 ldns_resolver_set_tsig_keydata(ldns_resolver *r, char *tsig_keydata)
575 LDNS_FREE(r->_tsig_keydata);
576 r->_tsig_keydata = strdup(tsig_keydata);
580 ldns_resolver_set_random(ldns_resolver *r, bool b)
585 /* more sophisticated functions */
587 ldns_resolver_new(void)
591 r = LDNS_MALLOC(ldns_resolver);
596 r->_searchlist = NULL;
597 r->_nameservers = NULL;
600 /* defaults are filled out */
601 ldns_resolver_set_searchlist_count(r, 0);
602 ldns_resolver_set_nameserver_count(r, 0);
603 ldns_resolver_set_usevc(r, 0);
604 ldns_resolver_set_port(r, LDNS_PORT);
605 ldns_resolver_set_domain(r, NULL);
606 ldns_resolver_set_defnames(r, false);
607 ldns_resolver_set_retry(r, 3);
608 ldns_resolver_set_retrans(r, 2);
609 ldns_resolver_set_fallback(r, true);
610 ldns_resolver_set_fail(r, false);
611 ldns_resolver_set_edns_udp_size(r, 0);
612 ldns_resolver_set_dnssec(r, false);
613 ldns_resolver_set_dnssec_cd(r, false);
614 ldns_resolver_set_dnssec_anchors(r, NULL);
615 ldns_resolver_set_ip6(r, LDNS_RESOLV_INETANY);
616 ldns_resolver_set_igntc(r, false);
617 ldns_resolver_set_recursive(r, false);
618 ldns_resolver_set_dnsrch(r, true);
620 /* randomize the nameserver to be queried
621 * when there are multiple
623 ldns_resolver_set_random(r, true);
625 ldns_resolver_set_debug(r, 0);
627 r->_timeout.tv_sec = LDNS_DEFAULT_TIMEOUT_SEC;
628 r->_timeout.tv_usec = LDNS_DEFAULT_TIMEOUT_USEC;
630 /* TODO: fd=0 is actually a valid socket (stdin),
633 r->_axfr_soa_count = 0;
635 r->_cur_axfr_pkt = NULL;
637 r->_tsig_keyname = NULL;
638 r->_tsig_keydata = NULL;
639 r->_tsig_algorithm = NULL;
644 ldns_resolver_new_frm_fp(ldns_resolver **res, FILE *fp)
646 return ldns_resolver_new_frm_fp_l(res, fp, NULL);
650 ldns_resolver_new_frm_fp_l(ldns_resolver **res, FILE *fp, int *line_nr)
653 const char *keyword[LDNS_RESOLV_KEYWORDS];
654 char word[LDNS_MAX_LINELEN + 1];
663 int lnr = 0, oldline;
664 if(!line_nr) line_nr = &lnr;
669 * 1: default domain dname
670 * 2: NS aaaa or a record
673 /* recognized keywords */
674 keyword[LDNS_RESOLV_NAMESERVER] = "nameserver";
675 keyword[LDNS_RESOLV_DEFDOMAIN] = "domain";
676 keyword[LDNS_RESOLV_SEARCH] = "search";
677 /* these two are read but not used atm TODO */
678 keyword[LDNS_RESOLV_SORTLIST] = "sortlist";
679 keyword[LDNS_RESOLV_OPTIONS] = "options";
680 keyword[LDNS_RESOLV_ANCHOR] = "anchor";
681 expect = LDNS_RESOLV_KEYWORD;
683 r = ldns_resolver_new();
685 return LDNS_STATUS_MEM_ERR;
691 expect = LDNS_RESOLV_KEYWORD;
694 if (word[0] == '#') {
696 if(oldline == *line_nr) {
697 /* skip until end of line */
701 } while(c != EOF && c != '\n');
702 if(c=='\n' && line_nr) (*line_nr)++;
704 /* and read next to prepare for further parsing */
710 case LDNS_RESOLV_KEYWORD:
712 gtr = ldns_fget_token_l(fp, word, LDNS_PARSE_NORMAL, 0, line_nr);
714 if(word[0] == '#') continue;
715 for(i = 0; i < LDNS_RESOLV_KEYWORDS; i++) {
716 if (strcasecmp(keyword[i], word) == 0) {
717 /* chosen the keyword and
718 * expect values carefully
724 /* no keyword recognized */
725 if (expect == LDNS_RESOLV_KEYWORD) {
728 ldns_resolver_deep_free(r);
729 return LDNS_STATUS_SYNTAX_KEYWORD_ERR;
734 case LDNS_RESOLV_DEFDOMAIN:
735 /* default domain dname */
736 gtr = ldns_fget_token_l(fp, word, LDNS_PARSE_NORMAL, 0, line_nr);
738 return LDNS_STATUS_SYNTAX_MISSING_VALUE_ERR;
741 expect = LDNS_RESOLV_KEYWORD;
744 tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, word);
746 ldns_resolver_deep_free(r);
747 return LDNS_STATUS_SYNTAX_DNAME_ERR;
750 /* DOn't free, because we copy the pointer */
751 ldns_resolver_set_domain(r, tmp);
752 expect = LDNS_RESOLV_KEYWORD;
754 case LDNS_RESOLV_NAMESERVER:
755 /* NS aaaa or a record */
756 gtr = ldns_fget_token_l(fp, word, LDNS_PARSE_NORMAL, 0, line_nr);
758 return LDNS_STATUS_SYNTAX_MISSING_VALUE_ERR;
761 expect = LDNS_RESOLV_KEYWORD;
764 if(strchr(word, '%')) {
765 /* snip off interface labels,
766 * fe80::222:19ff:fe31:4222%eth0 */
767 strchr(word, '%')[0]=0;
769 tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA, word);
772 tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A, word);
774 /* could not parse it, exit */
776 ldns_resolver_deep_free(r);
777 return LDNS_STATUS_SYNTAX_ERR;
779 (void)ldns_resolver_push_nameserver(r, tmp);
780 ldns_rdf_deep_free(tmp);
781 expect = LDNS_RESOLV_KEYWORD;
783 case LDNS_RESOLV_SEARCH:
784 /* search list domain dname */
785 gtr = ldns_fget_token_l(fp, word, LDNS_PARSE_SKIP_SPACE, 0, line_nr);
786 b = LDNS_MALLOC(ldns_buffer);
788 ldns_resolver_deep_free(r);
789 return LDNS_STATUS_MEM_ERR;
792 ldns_buffer_new_frm_data(b, word, (size_t) gtr);
793 if(ldns_buffer_status(b) != LDNS_STATUS_OK) {
795 ldns_resolver_deep_free(r);
796 return LDNS_STATUS_MEM_ERR;
798 bgtr = ldns_bget_token(b, word, LDNS_PARSE_NORMAL, (size_t) gtr + 1);
802 expect = LDNS_RESOLV_KEYWORD;
806 tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, word);
808 ldns_resolver_deep_free(r);
810 return LDNS_STATUS_SYNTAX_DNAME_ERR;
813 ldns_resolver_push_searchlist(r, tmp);
815 ldns_rdf_deep_free(tmp);
816 bgtr = ldns_bget_token(b, word, LDNS_PARSE_NORMAL,
821 expect = LDNS_RESOLV_KEYWORD;
823 case LDNS_RESOLV_SORTLIST:
824 gtr = ldns_fget_token_l(fp, word, LDNS_PARSE_SKIP_SPACE, 0, line_nr);
825 /* sortlist not implemented atm */
826 expect = LDNS_RESOLV_KEYWORD;
828 case LDNS_RESOLV_OPTIONS:
829 gtr = ldns_fget_token_l(fp, word, LDNS_PARSE_SKIP_SPACE, 0, line_nr);
830 /* options not implemented atm */
831 expect = LDNS_RESOLV_KEYWORD;
833 case LDNS_RESOLV_ANCHOR:
834 /* a file containing a DNSSEC trust anchor */
835 gtr = ldns_fget_token_l(fp, word, LDNS_PARSE_NORMAL, 0, line_nr);
837 ldns_resolver_deep_free(r);
838 return LDNS_STATUS_SYNTAX_MISSING_VALUE_ERR;
841 expect = LDNS_RESOLV_KEYWORD;
846 tmp_rr = ldns_read_anchor_file(word);
847 (void) ldns_resolver_push_dnssec_anchor(r, tmp_rr);
848 ldns_rr_free(tmp_rr);
850 expect = LDNS_RESOLV_KEYWORD;
857 return LDNS_STATUS_OK;
859 ldns_resolver_deep_free(r);
860 return LDNS_STATUS_NULL;
865 ldns_resolver_new_frm_file(ldns_resolver **res, const char *filename)
872 fp = fopen(LDNS_RESOLV_CONF, "r");
875 fp = fopen(filename, "r");
878 return LDNS_STATUS_FILE_ERR;
881 s = ldns_resolver_new_frm_fp(&r, fp);
883 if (s == LDNS_STATUS_OK) {
886 return LDNS_STATUS_OK;
888 return LDNS_STATUS_NULL;
895 ldns_resolver_free(ldns_resolver *res)
901 ldns_resolver_deep_free(ldns_resolver *res)
906 if (res->_searchlist) {
907 for (i = 0; i < ldns_resolver_searchlist_count(res); i++) {
908 ldns_rdf_deep_free(res->_searchlist[i]);
910 LDNS_FREE(res->_searchlist);
912 if (res->_nameservers) {
913 for (i = 0; i < res->_nameserver_count; i++) {
914 ldns_rdf_deep_free(res->_nameservers[i]);
916 LDNS_FREE(res->_nameservers);
918 if (ldns_resolver_domain(res)) {
919 ldns_rdf_deep_free(ldns_resolver_domain(res));
921 if (res->_tsig_keyname) {
922 LDNS_FREE(res->_tsig_keyname);
924 if (res->_tsig_keydata) {
925 LDNS_FREE(res->_tsig_keydata);
927 if (res->_tsig_algorithm) {
928 LDNS_FREE(res->_tsig_algorithm);
931 if (res->_cur_axfr_pkt) {
932 ldns_pkt_free(res->_cur_axfr_pkt);
936 LDNS_FREE(res->_rtt);
938 if (res->_dnssec_anchors) {
939 ldns_rr_list_deep_free(res->_dnssec_anchors);
946 ldns_resolver_search(const ldns_resolver *r,const ldns_rdf *name,
947 ldns_rr_type t, ldns_rr_class c, uint16_t flags)
952 ldns_rdf **search_list;
956 str_dname = ldns_rdf2str(name);
958 if (ldns_dname_str_absolute(str_dname)) {
960 return ldns_resolver_query(r, name, t, c, flags);
961 } else if (ldns_resolver_dnsrch(r)) {
962 search_list = ldns_resolver_searchlist(r);
963 for (i = 0; i < ldns_resolver_searchlist_count(r); i++) {
964 new_name = ldns_dname_cat_clone(name, search_list[i]);
966 p = ldns_resolver_query(r, new_name, t, c, flags);
967 ldns_rdf_free(new_name);
969 if (ldns_pkt_get_rcode(p) == LDNS_RCODE_NOERROR) {
982 ldns_resolver_query(const ldns_resolver *r, const ldns_rdf *name,
983 ldns_rr_type t, ldns_rr_class c, uint16_t flags)
991 if (!ldns_resolver_defnames(r)) {
992 status = ldns_resolver_send(&pkt, (ldns_resolver *)r, name,
994 if (status == LDNS_STATUS_OK) {
1004 if (!ldns_resolver_domain(r)) {
1005 /* _defnames is set, but the domain is not....?? */
1006 status = ldns_resolver_send(&pkt, (ldns_resolver *)r, name,
1008 if (status == LDNS_STATUS_OK) {
1018 newname = ldns_dname_cat_clone((const ldns_rdf*)name, ldns_resolver_domain(r));
1026 (void)ldns_resolver_send(&pkt, (ldns_resolver *)r, newname, t, c,
1029 ldns_rdf_free(newname);
1035 ldns_resolver_backup_rtt(ldns_resolver *r)
1038 size_t *old_rtt = ldns_resolver_rtt(r);
1040 if (old_rtt && ldns_resolver_nameserver_count(r)) {
1041 new_rtt = LDNS_XMALLOC(size_t
1042 , ldns_resolver_nameserver_count(r));
1043 memcpy(new_rtt, old_rtt, sizeof(size_t)
1044 * ldns_resolver_nameserver_count(r));
1045 ldns_resolver_set_rtt(r, new_rtt);
1052 ldns_resolver_restore_rtt(ldns_resolver *r, size_t *old_rtt)
1054 size_t *cur_rtt = ldns_resolver_rtt(r);
1059 ldns_resolver_set_rtt(r, old_rtt);
1063 ldns_resolver_send_pkt(ldns_pkt **answer, ldns_resolver *r,
1064 ldns_pkt *query_pkt)
1066 ldns_pkt *answer_pkt = NULL;
1067 ldns_status stat = LDNS_STATUS_OK;
1070 stat = ldns_send(&answer_pkt, (ldns_resolver *)r, query_pkt);
1071 if (stat != LDNS_STATUS_OK) {
1073 ldns_pkt_free(answer_pkt);
1077 /* if tc=1 fall back to EDNS and/or TCP */
1078 /* check for tcp first (otherwise we don't care about tc=1) */
1079 if (!ldns_resolver_usevc(r) && ldns_resolver_fallback(r)) {
1080 if (ldns_pkt_tc(answer_pkt)) {
1081 /* was EDNS0 set? */
1082 if (ldns_pkt_edns_udp_size(query_pkt) == 0) {
1083 ldns_pkt_set_edns_udp_size(query_pkt
1085 ldns_pkt_free(answer_pkt);
1086 /* Nameservers should not become
1087 * unreachable because fragments are
1088 * dropped (network error). We might
1089 * still have success with TCP.
1090 * Therefore maintain reachability
1091 * statuses of the nameservers by
1092 * backup and restore the rtt list.
1094 rtt = ldns_resolver_backup_rtt(r);
1095 stat = ldns_send(&answer_pkt, r
1097 ldns_resolver_restore_rtt(r, rtt);
1099 /* either way, if it is still truncated, use TCP */
1100 if (stat != LDNS_STATUS_OK ||
1101 ldns_pkt_tc(answer_pkt)) {
1102 ldns_resolver_set_usevc(r, true);
1103 ldns_pkt_free(answer_pkt);
1104 stat = ldns_send(&answer_pkt, r, query_pkt);
1105 ldns_resolver_set_usevc(r, false);
1112 *answer = answer_pkt;
1119 ldns_resolver_prepare_query_pkt(ldns_pkt **query_pkt, ldns_resolver *r,
1120 const ldns_rdf *name, ldns_rr_type t,
1121 ldns_rr_class c, uint16_t flags)
1125 /* prepare a question pkt from the parameters
1126 * and then send this */
1127 *query_pkt = ldns_pkt_query_new(ldns_rdf_clone(name), t, c, flags);
1129 return LDNS_STATUS_ERR;
1132 /* set DO bit if necessary */
1133 if (ldns_resolver_dnssec(r)) {
1134 if (ldns_resolver_edns_udp_size(r) == 0) {
1135 ldns_resolver_set_edns_udp_size(r, 4096);
1137 ldns_pkt_set_edns_do(*query_pkt, true);
1138 if (ldns_resolver_dnssec_cd(r) || (flags & LDNS_CD)) {
1139 ldns_pkt_set_cd(*query_pkt, true);
1143 /* transfer the udp_edns_size from the resolver to the packet */
1144 if (ldns_resolver_edns_udp_size(r) != 0) {
1145 ldns_pkt_set_edns_udp_size(*query_pkt, ldns_resolver_edns_udp_size(r));
1148 /* set the timestamp */
1149 now.tv_sec = time(NULL);
1151 ldns_pkt_set_timestamp(*query_pkt, now);
1154 if (ldns_resolver_debug(r)) {
1155 ldns_pkt_print(stdout, *query_pkt);
1158 /* only set the id if it is not set yet */
1159 if (ldns_pkt_id(*query_pkt) == 0) {
1160 ldns_pkt_set_random_id(*query_pkt);
1163 return LDNS_STATUS_OK;
1168 ldns_resolver_send(ldns_pkt **answer, ldns_resolver *r, const ldns_rdf *name,
1169 ldns_rr_type t, ldns_rr_class c, uint16_t flags)
1171 ldns_pkt *query_pkt;
1172 ldns_pkt *answer_pkt;
1176 assert(name != NULL);
1180 /* do all the preprocessing here, then fire of an query to
1187 c= LDNS_RR_CLASS_IN;
1189 if (0 == ldns_resolver_nameserver_count(r)) {
1190 return LDNS_STATUS_RES_NO_NS;
1192 if (ldns_rdf_get_type(name) != LDNS_RDF_TYPE_DNAME) {
1193 return LDNS_STATUS_RES_QUERY;
1196 status = ldns_resolver_prepare_query_pkt(&query_pkt, r, name,
1198 if (status != LDNS_STATUS_OK) {
1202 /* if tsig values are set, tsign it */
1203 /* TODO: make last 3 arguments optional too? maybe make complete
1204 rr instead of seperate values in resolver (and packet)
1206 should this go in pkt_prepare?
1208 if (ldns_resolver_tsig_keyname(r) && ldns_resolver_tsig_keydata(r)) {
1210 status = ldns_pkt_tsig_sign(query_pkt,
1211 ldns_resolver_tsig_keyname(r),
1212 ldns_resolver_tsig_keydata(r),
1213 300, ldns_resolver_tsig_algorithm(r), NULL);
1214 if (status != LDNS_STATUS_OK) {
1215 return LDNS_STATUS_CRYPTO_TSIG_ERR;
1218 return LDNS_STATUS_CRYPTO_TSIG_ERR;
1219 #endif /* HAVE_SSL */
1222 status = ldns_resolver_send_pkt(&answer_pkt, r, query_pkt);
1223 ldns_pkt_free(query_pkt);
1225 /* allows answer to be NULL when not interested in return value */
1227 *answer = answer_pkt;
1233 ldns_axfr_next(ldns_resolver *resolver)
1236 uint8_t *packet_wire;
1237 size_t packet_wire_size;
1238 ldns_lookup_table *rcode;
1241 /* check if start() has been called */
1242 if (!resolver || resolver->_socket == 0) {
1246 if (resolver->_cur_axfr_pkt) {
1247 if (resolver->_axfr_i == ldns_pkt_ancount(resolver->_cur_axfr_pkt)) {
1248 ldns_pkt_free(resolver->_cur_axfr_pkt);
1249 resolver->_cur_axfr_pkt = NULL;
1250 return ldns_axfr_next(resolver);
1252 cur_rr = ldns_rr_clone(ldns_rr_list_rr(
1253 ldns_pkt_answer(resolver->_cur_axfr_pkt),
1254 resolver->_axfr_i));
1255 resolver->_axfr_i++;
1256 if (ldns_rr_get_type(cur_rr) == LDNS_RR_TYPE_SOA) {
1257 resolver->_axfr_soa_count++;
1258 if (resolver->_axfr_soa_count >= 2) {
1260 close(resolver->_socket);
1262 closesocket(resolver->_socket);
1264 resolver->_socket = 0;
1265 ldns_pkt_free(resolver->_cur_axfr_pkt);
1266 resolver->_cur_axfr_pkt = NULL;
1271 packet_wire = ldns_tcp_read_wire(resolver->_socket, &packet_wire_size);
1275 status = ldns_wire2pkt(&resolver->_cur_axfr_pkt, packet_wire,
1279 resolver->_axfr_i = 0;
1280 if (status != LDNS_STATUS_OK) {
1281 /* TODO: make status return type of this function (...api change) */
1282 fprintf(stderr, "Error parsing rr during AXFR: %s\n", ldns_get_errorstr_by_id(status));
1284 /* RoRi: we must now also close the socket, otherwise subsequent uses of the
1285 same resolver structure will fail because the link is still open or
1286 in an undefined state */
1288 close(resolver->_socket);
1290 closesocket(resolver->_socket);
1292 resolver->_socket = 0;
1295 } else if (ldns_pkt_get_rcode(resolver->_cur_axfr_pkt) != 0) {
1296 rcode = ldns_lookup_by_id(ldns_rcodes, (int) ldns_pkt_get_rcode(resolver->_cur_axfr_pkt));
1297 fprintf(stderr, "Error in AXFR: %s\n", rcode->name);
1299 /* RoRi: we must now also close the socket, otherwise subsequent uses of the
1300 same resolver structure will fail because the link is still open or
1301 in an undefined state */
1303 close(resolver->_socket);
1305 closesocket(resolver->_socket);
1307 resolver->_socket = 0;
1311 return ldns_axfr_next(resolver);
1319 ldns_axfr_complete(const ldns_resolver *res)
1321 /* complete when soa count is 2? */
1322 return res->_axfr_soa_count == 2;
1326 ldns_axfr_last_pkt(const ldns_resolver *res)
1328 return res->_cur_axfr_pkt;
1331 /* random isn't really that good */
1333 ldns_resolver_nameservers_randomize(ldns_resolver *r)
1336 ldns_rdf **ns, *tmp;
1338 /* should I check for ldns_resolver_random?? */
1341 ns = ldns_resolver_nameservers(r);
1342 for (i = 0; i < ldns_resolver_nameserver_count(r); i++) {
1343 j = ldns_get_random() % ldns_resolver_nameserver_count(r);
1348 ldns_resolver_set_nameservers(r, ns);