1 /*
2 * iterator/iter_utils.c - iterative resolver module utility functions.
3 *
4 * Copyright (c) 2007, NLnet Labs. All rights reserved.
5 *
6 * This software is open source.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * Redistributions of source code must retain the above copyright notice,
13 * this list of conditions and the following disclaimer.
14 *
15 * Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 *
19 * Neither the name of the NLNET LABS nor the names of its contributors may
20 * be used to endorse or promote products derived from this software without
21 * specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 /**
37 * \file
38 *
39 * This file contains functions to assist the iterator module.
40 * Configuration options. Forward zones.
41 */
42 #include "config.h"
43 #include "iterator/iter_utils.h"
44 #include "iterator/iterator.h"
45 #include "iterator/iter_hints.h"
46 #include "iterator/iter_fwd.h"
47 #include "iterator/iter_donotq.h"
48 #include "iterator/iter_delegpt.h"
49 #include "iterator/iter_priv.h"
50 #include "services/cache/infra.h"
51 #include "services/cache/dns.h"
52 #include "services/cache/rrset.h"
53 #include "services/outside_network.h"
54 #include "util/net_help.h"
55 #include "util/module.h"
56 #include "util/log.h"
57 #include "util/config_file.h"
58 #include "util/regional.h"
59 #include "util/data/msgparse.h"
60 #include "util/data/dname.h"
61 #include "util/random.h"
62 #include "util/fptr_wlist.h"
63 #include "validator/val_anchor.h"
64 #include "validator/val_kcache.h"
65 #include "validator/val_kentry.h"
66 #include "validator/val_utils.h"
67 #include "validator/val_sigcrypt.h"
68 #include "sldns/sbuffer.h"
69 #include "sldns/str2wire.h"
70
71 /** time when nameserver glue is said to be 'recent' */
72 #define SUSPICION_RECENT_EXPIRY 86400
73
74 /** if NAT64 is enabled and no NAT64 prefix is configured, first fall back to
75 * DNS64 prefix. If that is not configured, fall back to this default value.
76 */
77 static const char DEFAULT_NAT64_PREFIX[] = "64:ff9b::/96";
78
79 /** fillup fetch policy array */
80 static int
fetch_fill(int * target_fetch_policy,int max_dependency_depth,const char * str)81 fetch_fill(int* target_fetch_policy, int max_dependency_depth, const char* str)
82 {
83 char* s = (char*)str, *e;
84 int i;
85 for(i=0; i<max_dependency_depth+1; i++) {
86 target_fetch_policy[i] = strtol(s, &e, 10);
87 if(s == e) {
88 log_err("cannot parse fetch policy number %s", s);
89 return 0;
90 }
91 s = e;
92 }
93 return 1;
94 }
95
96 /** Read config string that represents the target fetch policy */
97 int
read_fetch_policy(int ** target_fetch_policy,int * max_dependency_depth,const char * str)98 read_fetch_policy(int** target_fetch_policy, int* max_dependency_depth,
99 const char* str)
100 {
101 int count = cfg_count_numbers(str);
102 if(count < 1) {
103 log_err("Cannot parse target fetch policy: \"%s\"", str);
104 return 0;
105 }
106 *max_dependency_depth = count - 1;
107 *target_fetch_policy = (int*)calloc(
108 (size_t)(*max_dependency_depth)+1, sizeof(int));
109 if(!*target_fetch_policy) {
110 log_err("alloc fetch policy: out of memory");
111 return 0;
112 }
113 if(!fetch_fill(*target_fetch_policy, *max_dependency_depth, str))
114 return 0;
115 return 1;
116 }
117
118 struct rbtree_type*
caps_white_create(void)119 caps_white_create(void)
120 {
121 struct rbtree_type* caps_white = rbtree_create(name_tree_compare);
122 if(!caps_white)
123 log_err("out of memory");
124 return caps_white;
125 }
126
127 /** delete caps_whitelist element */
128 static void
caps_free(struct rbnode_type * n,void * ATTR_UNUSED (d))129 caps_free(struct rbnode_type* n, void* ATTR_UNUSED(d))
130 {
131 if(n) {
132 free(((struct name_tree_node*)n)->name);
133 free(n);
134 }
135 }
136
137 void
caps_white_delete(struct rbtree_type * caps_white)138 caps_white_delete(struct rbtree_type* caps_white)
139 {
140 if(!caps_white)
141 return;
142 traverse_postorder(caps_white, caps_free, NULL);
143 free(caps_white);
144 }
145
146 int
caps_white_apply_cfg(rbtree_type * ntree,struct config_file * cfg)147 caps_white_apply_cfg(rbtree_type* ntree, struct config_file* cfg)
148 {
149 struct config_strlist* p;
150 for(p=cfg->caps_whitelist; p; p=p->next) {
151 struct name_tree_node* n;
152 size_t len;
153 uint8_t* nm = sldns_str2wire_dname(p->str, &len);
154 if(!nm) {
155 log_err("could not parse %s", p->str);
156 return 0;
157 }
158 n = (struct name_tree_node*)calloc(1, sizeof(*n));
159 if(!n) {
160 log_err("out of memory");
161 free(nm);
162 return 0;
163 }
164 n->node.key = n;
165 n->name = nm;
166 n->len = len;
167 n->labs = dname_count_labels(nm);
168 n->dclass = LDNS_RR_CLASS_IN;
169 if(!name_tree_insert(ntree, n, nm, len, n->labs, n->dclass)) {
170 /* duplicate element ignored, idempotent */
171 free(n->name);
172 free(n);
173 }
174 }
175 name_tree_init_parents(ntree);
176 return 1;
177 }
178
179 int
nat64_apply_cfg(struct iter_nat64 * nat64,struct config_file * cfg)180 nat64_apply_cfg(struct iter_nat64* nat64, struct config_file* cfg)
181 {
182 const char *nat64_prefix;
183
184 nat64_prefix = cfg->nat64_prefix;
185 if(!nat64_prefix)
186 nat64_prefix = cfg->dns64_prefix;
187 if(!nat64_prefix)
188 nat64_prefix = DEFAULT_NAT64_PREFIX;
189 if(!netblockstrtoaddr(nat64_prefix, 0, &nat64->nat64_prefix_addr,
190 &nat64->nat64_prefix_addrlen, &nat64->nat64_prefix_net)) {
191 log_err("cannot parse nat64-prefix netblock: %s", nat64_prefix);
192 return 0;
193 }
194 if(!addr_is_ip6(&nat64->nat64_prefix_addr,
195 nat64->nat64_prefix_addrlen)) {
196 log_err("nat64-prefix is not IPv6: %s", cfg->nat64_prefix);
197 return 0;
198 }
199 if(!prefixnet_is_nat64(nat64->nat64_prefix_net)) {
200 log_err("nat64-prefix length it not 32, 40, 48, 56, 64 or 96: %s",
201 nat64_prefix);
202 return 0;
203 }
204 nat64->use_nat64 = cfg->do_nat64;
205 return 1;
206 }
207
208 int
iter_apply_cfg(struct iter_env * iter_env,struct config_file * cfg)209 iter_apply_cfg(struct iter_env* iter_env, struct config_file* cfg)
210 {
211 int i;
212 /* target fetch policy */
213 if(!read_fetch_policy(&iter_env->target_fetch_policy,
214 &iter_env->max_dependency_depth, cfg->target_fetch_policy))
215 return 0;
216 for(i=0; i<iter_env->max_dependency_depth+1; i++)
217 verbose(VERB_QUERY, "target fetch policy for level %d is %d",
218 i, iter_env->target_fetch_policy[i]);
219
220 if(!iter_env->donotq)
221 iter_env->donotq = donotq_create();
222 if(!iter_env->donotq || !donotq_apply_cfg(iter_env->donotq, cfg)) {
223 log_err("Could not set donotqueryaddresses");
224 return 0;
225 }
226 if(!iter_env->priv)
227 iter_env->priv = priv_create();
228 if(!iter_env->priv || !priv_apply_cfg(iter_env->priv, cfg)) {
229 log_err("Could not set private addresses");
230 return 0;
231 }
232 if(cfg->caps_whitelist) {
233 if(!iter_env->caps_white)
234 iter_env->caps_white = caps_white_create();
235 if(!iter_env->caps_white || !caps_white_apply_cfg(
236 iter_env->caps_white, cfg)) {
237 log_err("Could not set capsforid whitelist");
238 return 0;
239 }
240
241 }
242
243 if(!nat64_apply_cfg(&iter_env->nat64, cfg)) {
244 log_err("Could not setup nat64");
245 return 0;
246 }
247
248 iter_env->supports_ipv6 = cfg->do_ip6;
249 iter_env->supports_ipv4 = cfg->do_ip4;
250 iter_env->outbound_msg_retry = cfg->outbound_msg_retry;
251 iter_env->max_sent_count = cfg->max_sent_count;
252 iter_env->max_query_restarts = cfg->max_query_restarts;
253 return 1;
254 }
255
256 /** filter out unsuitable targets.
257 * Applies NAT64 if needed as well by replacing the IPv4 with the synthesized
258 * IPv6 address.
259 * @param iter_env: iterator environment with ipv6-support flag.
260 * @param env: module environment with infra cache.
261 * @param name: zone name
262 * @param namelen: length of name
263 * @param qtype: query type (host order).
264 * @param now: current time
265 * @param a: address in delegation point we are examining.
266 * @return an integer that signals the target suitability.
267 * as follows:
268 * -1: The address should be omitted from the list.
269 * Because:
270 * o The address is bogus (DNSSEC validation failure).
271 * o Listed as donotquery
272 * o is ipv6 but no ipv6 support (in operating system).
273 * o is ipv4 but no ipv4 support (in operating system).
274 * o is lame
275 * Otherwise, an rtt in milliseconds.
276 * 0 .. USEFUL_SERVER_TOP_TIMEOUT-1
277 * The roundtrip time timeout estimate. less than 2 minutes.
278 * Note that util/rtt.c has a MIN_TIMEOUT of 50 msec, thus
279 * values 0 .. 49 are not used, unless that is changed.
280 * USEFUL_SERVER_TOP_TIMEOUT
281 * This value exactly is given for unresponsive blacklisted.
282 * USEFUL_SERVER_TOP_TIMEOUT+1
283 * For non-blacklisted servers: huge timeout, but has traffic.
284 * USEFUL_SERVER_TOP_TIMEOUT*1 ..
285 * parent-side lame servers get this penalty. A dispreferential
286 * server. (lame in delegpt).
287 * USEFUL_SERVER_TOP_TIMEOUT*2 ..
288 * dnsseclame servers get penalty
289 * USEFUL_SERVER_TOP_TIMEOUT*3 ..
290 * recursion lame servers get penalty
291 * UNKNOWN_SERVER_NICENESS
292 * If no information is known about the server, this is
293 * returned. 376 msec or so.
294 * +BLACKLIST_PENALTY (of USEFUL_TOP_TIMEOUT*4) for dnssec failed IPs.
295 *
296 * When a final value is chosen that is dnsseclame ; dnsseclameness checking
297 * is turned off (so we do not discard the reply).
298 * When a final value is chosen that is recursionlame; RD bit is set on query.
299 * Because of the numbers this means recursionlame also have dnssec lameness
300 * checking turned off.
301 */
302 static int
iter_filter_unsuitable(struct iter_env * iter_env,struct module_env * env,uint8_t * name,size_t namelen,uint16_t qtype,time_t now,struct delegpt_addr * a)303 iter_filter_unsuitable(struct iter_env* iter_env, struct module_env* env,
304 uint8_t* name, size_t namelen, uint16_t qtype, time_t now,
305 struct delegpt_addr* a)
306 {
307 int rtt, lame, reclame, dnsseclame;
308 if(a->bogus)
309 return -1; /* address of server is bogus */
310 if(donotq_lookup(iter_env->donotq, &a->addr, a->addrlen)) {
311 if(iter_env->nat64.use_nat64 &&
312 addr_is_ip6(&a->addr, a->addrlen) &&
313 a->addrlen == iter_env->nat64.nat64_prefix_addrlen &&
314 addr_in_common(&a->addr, 128,
315 &iter_env->nat64.nat64_prefix_addr,
316 iter_env->nat64.nat64_prefix_net,
317 iter_env->nat64.nat64_prefix_addrlen) ==
318 iter_env->nat64.nat64_prefix_net) {
319 /* The NAT64 is enabled, and address is IPv6, it is
320 * in the NAT64 prefix. It is allowed.
321 * So that in an IPv6-only cluster without internet
322 * access, that makes the NAT64 translation continue
323 * to work. The NAT64 prefix is allowed. */
324 /* Otherwise, after a timeout, the already NAT64
325 * translated address would be treated differently,
326 * and that causes confusion. */
327 log_addr(VERB_ALGO, "the addr is on the donotquery "
328 "list, but allowed because it is NAT64",
329 &a->addr, a->addrlen);
330 } else {
331 log_addr(VERB_ALGO, "skip addr on the donotquery list",
332 &a->addr, a->addrlen);
333 return -1; /* server is on the donotquery list */
334 }
335 }
336 if(!iter_env->supports_ipv6 && addr_is_ip6(&a->addr, a->addrlen)) {
337 return -1; /* there is no ip6 available */
338 }
339 if(!iter_env->supports_ipv4 && !iter_env->nat64.use_nat64 &&
340 !addr_is_ip6(&a->addr, a->addrlen)) {
341 return -1; /* there is no ip4 available */
342 }
343 if(iter_env->nat64.use_nat64 && !addr_is_ip6(&a->addr, a->addrlen)) {
344 struct sockaddr_storage real_addr;
345 socklen_t real_addrlen;
346 addr_to_nat64(&a->addr, &iter_env->nat64.nat64_prefix_addr,
347 iter_env->nat64.nat64_prefix_addrlen,
348 iter_env->nat64.nat64_prefix_net,
349 &real_addr, &real_addrlen);
350 log_name_addr(VERB_QUERY, "NAT64 apply: from: ",
351 name, &a->addr, a->addrlen);
352 log_name_addr(VERB_QUERY, "NAT64 apply: to: ",
353 name, &real_addr, real_addrlen);
354 a->addr = real_addr;
355 a->addrlen = real_addrlen;
356 }
357 /* check lameness - need zone , class info */
358 if(infra_get_lame_rtt(env->infra_cache, &a->addr, a->addrlen,
359 name, namelen, qtype, &lame, &dnsseclame, &reclame,
360 &rtt, now)) {
361 log_addr(VERB_ALGO, "servselect", &a->addr, a->addrlen);
362 verbose(VERB_ALGO, " rtt=%d%s%s%s%s%s", rtt,
363 lame?" LAME":"",
364 dnsseclame?" DNSSEC_LAME":"",
365 a->dnsseclame?" ADDR_DNSSEC_LAME":"",
366 reclame?" REC_LAME":"",
367 a->lame?" ADDR_LAME":"");
368 if(lame)
369 return -1; /* server is lame */
370 else if(rtt >= USEFUL_SERVER_TOP_TIMEOUT)
371 /* server is unresponsive,
372 * we used to return TOP_TIMEOUT, but fairly useless,
373 * because if == TOP_TIMEOUT is dropped because
374 * blacklisted later, instead, remove it here, so
375 * other choices (that are not blacklisted) can be
376 * tried */
377 return -1;
378 /* select remainder from worst to best */
379 else if(reclame)
380 return rtt+USEFUL_SERVER_TOP_TIMEOUT*3; /* nonpref */
381 else if(dnsseclame || a->dnsseclame)
382 return rtt+USEFUL_SERVER_TOP_TIMEOUT*2; /* nonpref */
383 else if(a->lame)
384 return rtt+USEFUL_SERVER_TOP_TIMEOUT+1; /* nonpref */
385 else return rtt;
386 }
387 /* no server information present */
388 if(a->dnsseclame)
389 return UNKNOWN_SERVER_NICENESS+USEFUL_SERVER_TOP_TIMEOUT*2; /* nonpref */
390 else if(a->lame)
391 return USEFUL_SERVER_TOP_TIMEOUT+1+UNKNOWN_SERVER_NICENESS; /* nonpref */
392 return UNKNOWN_SERVER_NICENESS;
393 }
394
395 /** lookup RTT information, and also store fastest rtt (if any) */
396 static int
iter_fill_rtt(struct iter_env * iter_env,struct module_env * env,uint8_t * name,size_t namelen,uint16_t qtype,time_t now,struct delegpt * dp,int * best_rtt,struct sock_list * blacklist,size_t * num_suitable_results)397 iter_fill_rtt(struct iter_env* iter_env, struct module_env* env,
398 uint8_t* name, size_t namelen, uint16_t qtype, time_t now,
399 struct delegpt* dp, int* best_rtt, struct sock_list* blacklist,
400 size_t* num_suitable_results)
401 {
402 int got_it = 0;
403 struct delegpt_addr* a;
404 *num_suitable_results = 0;
405
406 if(dp->bogus)
407 return 0; /* NS bogus, all bogus, nothing found */
408 for(a=dp->result_list; a; a = a->next_result) {
409 a->sel_rtt = iter_filter_unsuitable(iter_env, env,
410 name, namelen, qtype, now, a);
411 if(a->sel_rtt != -1) {
412 if(sock_list_find(blacklist, &a->addr, a->addrlen))
413 a->sel_rtt += BLACKLIST_PENALTY;
414
415 if(!got_it) {
416 *best_rtt = a->sel_rtt;
417 got_it = 1;
418 } else if(a->sel_rtt < *best_rtt) {
419 *best_rtt = a->sel_rtt;
420 }
421 (*num_suitable_results)++;
422 }
423 }
424 return got_it;
425 }
426
427 /** compare two rtts, return -1, 0 or 1 */
428 static int
rtt_compare(const void * x,const void * y)429 rtt_compare(const void* x, const void* y)
430 {
431 if(*(int*)x == *(int*)y)
432 return 0;
433 if(*(int*)x > *(int*)y)
434 return 1;
435 return -1;
436 }
437
438 /** get RTT for the Nth fastest server */
439 static int
nth_rtt(struct delegpt_addr * result_list,size_t num_results,size_t n)440 nth_rtt(struct delegpt_addr* result_list, size_t num_results, size_t n)
441 {
442 int rtt_band;
443 size_t i;
444 int* rtt_list, *rtt_index;
445
446 if(num_results < 1 || n >= num_results) {
447 return -1;
448 }
449
450 rtt_list = calloc(num_results, sizeof(int));
451 if(!rtt_list) {
452 log_err("malloc failure: allocating rtt_list");
453 return -1;
454 }
455 rtt_index = rtt_list;
456
457 for(i=0; i<num_results && result_list; i++) {
458 if(result_list->sel_rtt != -1) {
459 *rtt_index = result_list->sel_rtt;
460 rtt_index++;
461 }
462 result_list=result_list->next_result;
463 }
464 qsort(rtt_list, num_results, sizeof(*rtt_list), rtt_compare);
465
466 log_assert(n > 0);
467 rtt_band = rtt_list[n-1];
468 free(rtt_list);
469
470 return rtt_band;
471 }
472
473 /** filter the address list, putting best targets at front,
474 * returns number of best targets (or 0, no suitable targets) */
475 static int
iter_filter_order(struct iter_env * iter_env,struct module_env * env,uint8_t * name,size_t namelen,uint16_t qtype,time_t now,struct delegpt * dp,int * selected_rtt,int open_target,struct sock_list * blacklist,time_t prefetch)476 iter_filter_order(struct iter_env* iter_env, struct module_env* env,
477 uint8_t* name, size_t namelen, uint16_t qtype, time_t now,
478 struct delegpt* dp, int* selected_rtt, int open_target,
479 struct sock_list* blacklist, time_t prefetch)
480 {
481 int got_num = 0, low_rtt = 0, swap_to_front, rtt_band = RTT_BAND, nth;
482 int alllame = 0;
483 size_t num_results;
484 struct delegpt_addr* a, *n, *prev=NULL;
485
486 /* fillup sel_rtt and find best rtt in the bunch */
487 got_num = iter_fill_rtt(iter_env, env, name, namelen, qtype, now, dp,
488 &low_rtt, blacklist, &num_results);
489 if(got_num == 0)
490 return 0;
491 if(low_rtt >= USEFUL_SERVER_TOP_TIMEOUT &&
492 /* If all missing (or not fully resolved) targets are lame,
493 * then use the remaining lame address. */
494 ((delegpt_count_missing_targets(dp, &alllame) > 0 && !alllame) ||
495 open_target > 0)) {
496 verbose(VERB_ALGO, "Bad choices, trying to get more choice");
497 return 0; /* we want more choice. The best choice is a bad one.
498 return 0 to force the caller to fetch more */
499 }
500
501 if(env->cfg->fast_server_permil != 0 && prefetch == 0 &&
502 num_results > env->cfg->fast_server_num &&
503 ub_random_max(env->rnd, 1000) < env->cfg->fast_server_permil) {
504 /* the query is not prefetch, but for a downstream client,
505 * there are more servers available then the fastest N we want
506 * to choose from. Limit our choice to the fastest servers. */
507 nth = nth_rtt(dp->result_list, num_results,
508 env->cfg->fast_server_num);
509 if(nth > 0) {
510 rtt_band = nth - low_rtt;
511 if(rtt_band > RTT_BAND)
512 rtt_band = RTT_BAND;
513 }
514 }
515
516 got_num = 0;
517 a = dp->result_list;
518 while(a) {
519 /* skip unsuitable targets */
520 if(a->sel_rtt == -1) {
521 prev = a;
522 a = a->next_result;
523 continue;
524 }
525 /* classify the server address and determine what to do */
526 swap_to_front = 0;
527 if(a->sel_rtt >= low_rtt && a->sel_rtt - low_rtt <= rtt_band) {
528 got_num++;
529 swap_to_front = 1;
530 } else if(a->sel_rtt<low_rtt && low_rtt-a->sel_rtt<=rtt_band) {
531 got_num++;
532 swap_to_front = 1;
533 }
534 /* swap to front if necessary, or move to next result */
535 if(swap_to_front && prev) {
536 n = a->next_result;
537 prev->next_result = n;
538 a->next_result = dp->result_list;
539 dp->result_list = a;
540 a = n;
541 } else {
542 prev = a;
543 a = a->next_result;
544 }
545 }
546 *selected_rtt = low_rtt;
547
548 if (env->cfg->prefer_ip6) {
549 int got_num6 = 0;
550 int low_rtt6 = 0;
551 int i;
552 int attempt = -1; /* filter to make sure addresses have
553 less attempts on them than the first, to force round
554 robin when all the IPv6 addresses fail */
555 int num4ok = 0; /* number ip4 at low attempt count */
556 int num4_lowrtt = 0;
557 prev = NULL;
558 a = dp->result_list;
559 for(i = 0; i < got_num; i++) {
560 if(!a) break; /* robustness */
561 swap_to_front = 0;
562 if(a->addr.ss_family != AF_INET6 && attempt == -1) {
563 /* if we only have ip4 at low attempt count,
564 * then ip6 is failing, and we need to
565 * select one of the remaining IPv4 addrs */
566 attempt = a->attempts;
567 num4ok++;
568 num4_lowrtt = a->sel_rtt;
569 } else if(a->addr.ss_family != AF_INET6 && attempt == a->attempts) {
570 num4ok++;
571 if(num4_lowrtt == 0 || a->sel_rtt < num4_lowrtt) {
572 num4_lowrtt = a->sel_rtt;
573 }
574 }
575 if(a->addr.ss_family == AF_INET6) {
576 if(attempt == -1) {
577 attempt = a->attempts;
578 } else if(a->attempts > attempt) {
579 break;
580 }
581 got_num6++;
582 swap_to_front = 1;
583 if(low_rtt6 == 0 || a->sel_rtt < low_rtt6) {
584 low_rtt6 = a->sel_rtt;
585 }
586 }
587 /* swap to front if IPv6, or move to next result */
588 if(swap_to_front && prev) {
589 n = a->next_result;
590 prev->next_result = n;
591 a->next_result = dp->result_list;
592 dp->result_list = a;
593 a = n;
594 } else {
595 prev = a;
596 a = a->next_result;
597 }
598 }
599 if(got_num6 > 0) {
600 got_num = got_num6;
601 *selected_rtt = low_rtt6;
602 } else if(num4ok > 0) {
603 got_num = num4ok;
604 *selected_rtt = num4_lowrtt;
605 }
606 } else if (env->cfg->prefer_ip4) {
607 int got_num4 = 0;
608 int low_rtt4 = 0;
609 int i;
610 int attempt = -1; /* filter to make sure addresses have
611 less attempts on them than the first, to force round
612 robin when all the IPv4 addresses fail */
613 int num6ok = 0; /* number ip6 at low attempt count */
614 int num6_lowrtt = 0;
615 prev = NULL;
616 a = dp->result_list;
617 for(i = 0; i < got_num; i++) {
618 if(!a) break; /* robustness */
619 swap_to_front = 0;
620 if(a->addr.ss_family != AF_INET && attempt == -1) {
621 /* if we only have ip6 at low attempt count,
622 * then ip4 is failing, and we need to
623 * select one of the remaining IPv6 addrs */
624 attempt = a->attempts;
625 num6ok++;
626 num6_lowrtt = a->sel_rtt;
627 } else if(a->addr.ss_family != AF_INET && attempt == a->attempts) {
628 num6ok++;
629 if(num6_lowrtt == 0 || a->sel_rtt < num6_lowrtt) {
630 num6_lowrtt = a->sel_rtt;
631 }
632 }
633 if(a->addr.ss_family == AF_INET) {
634 if(attempt == -1) {
635 attempt = a->attempts;
636 } else if(a->attempts > attempt) {
637 break;
638 }
639 got_num4++;
640 swap_to_front = 1;
641 if(low_rtt4 == 0 || a->sel_rtt < low_rtt4) {
642 low_rtt4 = a->sel_rtt;
643 }
644 }
645 /* swap to front if IPv4, or move to next result */
646 if(swap_to_front && prev) {
647 n = a->next_result;
648 prev->next_result = n;
649 a->next_result = dp->result_list;
650 dp->result_list = a;
651 a = n;
652 } else {
653 prev = a;
654 a = a->next_result;
655 }
656 }
657 if(got_num4 > 0) {
658 got_num = got_num4;
659 *selected_rtt = low_rtt4;
660 } else if(num6ok > 0) {
661 got_num = num6ok;
662 *selected_rtt = num6_lowrtt;
663 }
664 }
665 return got_num;
666 }
667
668 struct delegpt_addr*
iter_server_selection(struct iter_env * iter_env,struct module_env * env,struct delegpt * dp,uint8_t * name,size_t namelen,uint16_t qtype,int * dnssec_lame,int * chase_to_rd,int open_target,struct sock_list * blacklist,time_t prefetch)669 iter_server_selection(struct iter_env* iter_env,
670 struct module_env* env, struct delegpt* dp,
671 uint8_t* name, size_t namelen, uint16_t qtype, int* dnssec_lame,
672 int* chase_to_rd, int open_target, struct sock_list* blacklist,
673 time_t prefetch)
674 {
675 int sel;
676 int selrtt;
677 struct delegpt_addr* a, *prev;
678 int num = iter_filter_order(iter_env, env, name, namelen, qtype,
679 *env->now, dp, &selrtt, open_target, blacklist, prefetch);
680
681 if(num == 0)
682 return NULL;
683 verbose(VERB_ALGO, "selrtt %d", selrtt);
684 if(selrtt > BLACKLIST_PENALTY) {
685 if(selrtt-BLACKLIST_PENALTY > USEFUL_SERVER_TOP_TIMEOUT*3) {
686 verbose(VERB_ALGO, "chase to "
687 "blacklisted recursion lame server");
688 *chase_to_rd = 1;
689 }
690 if(selrtt-BLACKLIST_PENALTY > USEFUL_SERVER_TOP_TIMEOUT*2) {
691 verbose(VERB_ALGO, "chase to "
692 "blacklisted dnssec lame server");
693 *dnssec_lame = 1;
694 }
695 } else {
696 if(selrtt > USEFUL_SERVER_TOP_TIMEOUT*3) {
697 verbose(VERB_ALGO, "chase to recursion lame server");
698 *chase_to_rd = 1;
699 }
700 if(selrtt > USEFUL_SERVER_TOP_TIMEOUT*2) {
701 verbose(VERB_ALGO, "chase to dnssec lame server");
702 *dnssec_lame = 1;
703 }
704 if(selrtt == USEFUL_SERVER_TOP_TIMEOUT) {
705 verbose(VERB_ALGO, "chase to blacklisted lame server");
706 return NULL;
707 }
708 }
709
710 if(num == 1) {
711 a = dp->result_list;
712 if(++a->attempts < iter_env->outbound_msg_retry)
713 return a;
714 dp->result_list = a->next_result;
715 return a;
716 }
717
718 /* randomly select a target from the list */
719 log_assert(num > 1);
720 /* grab secure random number, to pick unexpected server.
721 * also we need it to be threadsafe. */
722 sel = ub_random_max(env->rnd, num);
723 a = dp->result_list;
724 prev = NULL;
725 while(sel > 0 && a) {
726 prev = a;
727 a = a->next_result;
728 sel--;
729 }
730 if(!a) /* robustness */
731 return NULL;
732 if(++a->attempts < iter_env->outbound_msg_retry)
733 return a;
734 /* remove it from the delegation point result list */
735 if(prev)
736 prev->next_result = a->next_result;
737 else dp->result_list = a->next_result;
738 return a;
739 }
740
741 struct dns_msg*
dns_alloc_msg(sldns_buffer * pkt,struct msg_parse * msg,struct regional * region)742 dns_alloc_msg(sldns_buffer* pkt, struct msg_parse* msg,
743 struct regional* region)
744 {
745 struct dns_msg* m = (struct dns_msg*)regional_alloc(region,
746 sizeof(struct dns_msg));
747 if(!m)
748 return NULL;
749 memset(m, 0, sizeof(*m));
750 if(!parse_create_msg(pkt, msg, NULL, &m->qinfo, &m->rep, region)) {
751 log_err("malloc failure: allocating incoming dns_msg");
752 return NULL;
753 }
754 return m;
755 }
756
757 struct dns_msg*
dns_copy_msg(struct dns_msg * from,struct regional * region)758 dns_copy_msg(struct dns_msg* from, struct regional* region)
759 {
760 struct dns_msg* m = (struct dns_msg*)regional_alloc(region,
761 sizeof(struct dns_msg));
762 if(!m)
763 return NULL;
764 m->qinfo = from->qinfo;
765 if(!(m->qinfo.qname = regional_alloc_init(region, from->qinfo.qname,
766 from->qinfo.qname_len)))
767 return NULL;
768 if(!(m->rep = reply_info_copy(from->rep, NULL, region)))
769 return NULL;
770 return m;
771 }
772
773 void
iter_dns_store(struct module_env * env,struct query_info * msgqinf,struct reply_info * msgrep,int is_referral,time_t leeway,int pside,struct regional * region,uint16_t flags,time_t qstarttime,int is_valrec)774 iter_dns_store(struct module_env* env, struct query_info* msgqinf,
775 struct reply_info* msgrep, int is_referral, time_t leeway, int pside,
776 struct regional* region, uint16_t flags, time_t qstarttime,
777 int is_valrec)
778 {
779 if(!dns_cache_store(env, msgqinf, msgrep, is_referral, leeway,
780 pside, region, flags, qstarttime, is_valrec))
781 log_err("out of memory: cannot store data in cache");
782 }
783
784 int
iter_ns_probability(struct ub_randstate * rnd,int n,int m)785 iter_ns_probability(struct ub_randstate* rnd, int n, int m)
786 {
787 int sel;
788 if(n == m) /* 100% chance */
789 return 1;
790 /* we do not need secure random numbers here, but
791 * we do need it to be threadsafe, so we use this */
792 sel = ub_random_max(rnd, m);
793 return (sel < n);
794 }
795
796 /** detect dependency cycle for query and target */
797 static int
causes_cycle(struct module_qstate * qstate,uint8_t * name,size_t namelen,uint16_t t,uint16_t c)798 causes_cycle(struct module_qstate* qstate, uint8_t* name, size_t namelen,
799 uint16_t t, uint16_t c)
800 {
801 struct query_info qinf;
802 qinf.qname = name;
803 qinf.qname_len = namelen;
804 qinf.qtype = t;
805 qinf.qclass = c;
806 qinf.local_alias = NULL;
807 fptr_ok(fptr_whitelist_modenv_detect_cycle(
808 qstate->env->detect_cycle));
809 return (*qstate->env->detect_cycle)(qstate, &qinf,
810 (uint16_t)(BIT_RD|BIT_CD), qstate->is_priming,
811 qstate->is_valrec);
812 }
813
814 void
iter_mark_cycle_targets(struct module_qstate * qstate,struct delegpt * dp)815 iter_mark_cycle_targets(struct module_qstate* qstate, struct delegpt* dp)
816 {
817 struct delegpt_ns* ns;
818 for(ns = dp->nslist; ns; ns = ns->next) {
819 if(ns->resolved)
820 continue;
821 /* see if this ns as target causes dependency cycle */
822 if(causes_cycle(qstate, ns->name, ns->namelen,
823 LDNS_RR_TYPE_AAAA, qstate->qinfo.qclass) ||
824 causes_cycle(qstate, ns->name, ns->namelen,
825 LDNS_RR_TYPE_A, qstate->qinfo.qclass)) {
826 log_nametypeclass(VERB_QUERY, "skipping target due "
827 "to dependency cycle (harden-glue: no may "
828 "fix some of the cycles)",
829 ns->name, LDNS_RR_TYPE_A,
830 qstate->qinfo.qclass);
831 ns->resolved = 1;
832 }
833 }
834 }
835
836 void
iter_mark_pside_cycle_targets(struct module_qstate * qstate,struct delegpt * dp)837 iter_mark_pside_cycle_targets(struct module_qstate* qstate, struct delegpt* dp)
838 {
839 struct delegpt_ns* ns;
840 for(ns = dp->nslist; ns; ns = ns->next) {
841 if(ns->done_pside4 && ns->done_pside6)
842 continue;
843 /* see if this ns as target causes dependency cycle */
844 if(causes_cycle(qstate, ns->name, ns->namelen,
845 LDNS_RR_TYPE_A, qstate->qinfo.qclass)) {
846 log_nametypeclass(VERB_QUERY, "skipping target due "
847 "to dependency cycle", ns->name,
848 LDNS_RR_TYPE_A, qstate->qinfo.qclass);
849 ns->done_pside4 = 1;
850 }
851 if(causes_cycle(qstate, ns->name, ns->namelen,
852 LDNS_RR_TYPE_AAAA, qstate->qinfo.qclass)) {
853 log_nametypeclass(VERB_QUERY, "skipping target due "
854 "to dependency cycle", ns->name,
855 LDNS_RR_TYPE_AAAA, qstate->qinfo.qclass);
856 ns->done_pside6 = 1;
857 }
858 }
859 }
860
861 int
iter_dp_is_useless(struct query_info * qinfo,uint16_t qflags,struct delegpt * dp,int supports_ipv4,int supports_ipv6,int use_nat64)862 iter_dp_is_useless(struct query_info* qinfo, uint16_t qflags,
863 struct delegpt* dp, int supports_ipv4, int supports_ipv6,
864 int use_nat64)
865 {
866 struct delegpt_ns* ns;
867 struct delegpt_addr* a;
868
869 if(supports_ipv6 && use_nat64)
870 supports_ipv4 = 1;
871
872 /* check:
873 * o RD qflag is on.
874 * o no addresses are provided.
875 * o all NS items are required glue.
876 * OR
877 * o RD qflag is on.
878 * o no addresses are provided.
879 * o the query is for one of the nameservers in dp,
880 * and that nameserver is a glue-name for this dp.
881 */
882 if(!(qflags&BIT_RD))
883 return 0;
884 /* either available or unused targets,
885 * if they exist, the dp is not useless. */
886 for(a = dp->usable_list; a; a = a->next_usable) {
887 if(!addr_is_ip6(&a->addr, a->addrlen) && supports_ipv4)
888 return 0;
889 else if(addr_is_ip6(&a->addr, a->addrlen) && supports_ipv6)
890 return 0;
891 }
892 for(a = dp->result_list; a; a = a->next_result) {
893 if(!addr_is_ip6(&a->addr, a->addrlen) && supports_ipv4)
894 return 0;
895 else if(addr_is_ip6(&a->addr, a->addrlen) && supports_ipv6)
896 return 0;
897 }
898
899 /* see if query is for one of the nameservers, which is glue */
900 if( ((qinfo->qtype == LDNS_RR_TYPE_A && supports_ipv4) ||
901 (qinfo->qtype == LDNS_RR_TYPE_AAAA && supports_ipv6)) &&
902 dname_subdomain_c(qinfo->qname, dp->name) &&
903 delegpt_find_ns(dp, qinfo->qname, qinfo->qname_len))
904 return 1;
905
906 for(ns = dp->nslist; ns; ns = ns->next) {
907 if(ns->resolved) /* skip failed targets */
908 continue;
909 if(!dname_subdomain_c(ns->name, dp->name))
910 return 0; /* one address is not required glue */
911 }
912 return 1;
913 }
914
915 int
iter_qname_indicates_dnssec(struct module_env * env,struct query_info * qinfo)916 iter_qname_indicates_dnssec(struct module_env* env, struct query_info *qinfo)
917 {
918 struct trust_anchor* a;
919 if(!env || !env->anchors || !qinfo || !qinfo->qname)
920 return 0;
921 /* a trust anchor exists above the name? */
922 if((a=anchors_lookup(env->anchors, qinfo->qname, qinfo->qname_len,
923 qinfo->qclass))) {
924 if(a->numDS == 0 && a->numDNSKEY == 0) {
925 /* insecure trust point */
926 lock_basic_unlock(&a->lock);
927 return 0;
928 }
929 lock_basic_unlock(&a->lock);
930 return 1;
931 }
932 /* no trust anchor above it. */
933 return 0;
934 }
935
936 int
iter_indicates_dnssec(struct module_env * env,struct delegpt * dp,struct dns_msg * msg,uint16_t dclass)937 iter_indicates_dnssec(struct module_env* env, struct delegpt* dp,
938 struct dns_msg* msg, uint16_t dclass)
939 {
940 struct trust_anchor* a;
941 /* information not available, !env->anchors can be common */
942 if(!env || !env->anchors || !dp || !dp->name)
943 return 0;
944 /* a trust anchor exists with this name, RRSIGs expected */
945 if((a=anchor_find(env->anchors, dp->name, dp->namelabs, dp->namelen,
946 dclass))) {
947 if(a->numDS == 0 && a->numDNSKEY == 0) {
948 /* insecure trust point */
949 lock_basic_unlock(&a->lock);
950 return 0;
951 }
952 lock_basic_unlock(&a->lock);
953 return 1;
954 }
955 /* see if DS rrset was given, in AUTH section */
956 if(msg && msg->rep &&
957 reply_find_rrset_section_ns(msg->rep, dp->name, dp->namelen,
958 LDNS_RR_TYPE_DS, dclass))
959 return 1;
960 /* look in key cache */
961 if(env->key_cache) {
962 struct key_entry_key* kk = key_cache_obtain(env->key_cache,
963 dp->name, dp->namelen, dclass, env->scratch, *env->now);
964 if(kk) {
965 if(query_dname_compare(kk->name, dp->name) == 0) {
966 if(key_entry_isgood(kk) || key_entry_isbad(kk)) {
967 regional_free_all(env->scratch);
968 return 1;
969 } else if(key_entry_isnull(kk)) {
970 regional_free_all(env->scratch);
971 return 0;
972 }
973 }
974 regional_free_all(env->scratch);
975 }
976 }
977 return 0;
978 }
979
980 int
iter_msg_has_dnssec(struct dns_msg * msg)981 iter_msg_has_dnssec(struct dns_msg* msg)
982 {
983 size_t i;
984 if(!msg || !msg->rep)
985 return 0;
986 for(i=0; i<msg->rep->an_numrrsets + msg->rep->ns_numrrsets; i++) {
987 if(((struct packed_rrset_data*)msg->rep->rrsets[i]->
988 entry.data)->rrsig_count > 0)
989 return 1;
990 }
991 /* empty message has no DNSSEC info, with DNSSEC the reply is
992 * not empty (NSEC) */
993 return 0;
994 }
995
iter_msg_from_zone(struct dns_msg * msg,struct delegpt * dp,enum response_type type,uint16_t dclass)996 int iter_msg_from_zone(struct dns_msg* msg, struct delegpt* dp,
997 enum response_type type, uint16_t dclass)
998 {
999 if(!msg || !dp || !msg->rep || !dp->name)
1000 return 0;
1001 /* SOA RRset - always from reply zone */
1002 if(reply_find_rrset_section_an(msg->rep, dp->name, dp->namelen,
1003 LDNS_RR_TYPE_SOA, dclass) ||
1004 reply_find_rrset_section_ns(msg->rep, dp->name, dp->namelen,
1005 LDNS_RR_TYPE_SOA, dclass))
1006 return 1;
1007 if(type == RESPONSE_TYPE_REFERRAL) {
1008 size_t i;
1009 /* if it adds a single label, i.e. we expect .com,
1010 * and referral to example.com. NS ... , then origin zone
1011 * is .com. For a referral to sub.example.com. NS ... then
1012 * we do not know, since example.com. may be in between. */
1013 for(i=0; i<msg->rep->an_numrrsets+msg->rep->ns_numrrsets;
1014 i++) {
1015 struct ub_packed_rrset_key* s = msg->rep->rrsets[i];
1016 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NS &&
1017 ntohs(s->rk.rrset_class) == dclass) {
1018 int l = dname_count_labels(s->rk.dname);
1019 if(l == dp->namelabs + 1 &&
1020 dname_strict_subdomain(s->rk.dname,
1021 l, dp->name, dp->namelabs))
1022 return 1;
1023 }
1024 }
1025 return 0;
1026 }
1027 log_assert(type==RESPONSE_TYPE_ANSWER || type==RESPONSE_TYPE_CNAME);
1028 /* not a referral, and not lame delegation (upwards), so,
1029 * any NS rrset must be from the zone itself */
1030 if(reply_find_rrset_section_an(msg->rep, dp->name, dp->namelen,
1031 LDNS_RR_TYPE_NS, dclass) ||
1032 reply_find_rrset_section_ns(msg->rep, dp->name, dp->namelen,
1033 LDNS_RR_TYPE_NS, dclass))
1034 return 1;
1035 /* a DNSKEY set is expected at the zone apex as well */
1036 /* this is for 'minimal responses' for DNSKEYs */
1037 if(reply_find_rrset_section_an(msg->rep, dp->name, dp->namelen,
1038 LDNS_RR_TYPE_DNSKEY, dclass))
1039 return 1;
1040 return 0;
1041 }
1042
1043 /**
1044 * check equality of two rrsets
1045 * @param k1: rrset
1046 * @param k2: rrset
1047 * @return true if equal
1048 */
1049 static int
rrset_equal(struct ub_packed_rrset_key * k1,struct ub_packed_rrset_key * k2)1050 rrset_equal(struct ub_packed_rrset_key* k1, struct ub_packed_rrset_key* k2)
1051 {
1052 struct packed_rrset_data* d1 = (struct packed_rrset_data*)
1053 k1->entry.data;
1054 struct packed_rrset_data* d2 = (struct packed_rrset_data*)
1055 k2->entry.data;
1056 size_t i, t;
1057 if(k1->rk.dname_len != k2->rk.dname_len ||
1058 k1->rk.flags != k2->rk.flags ||
1059 k1->rk.type != k2->rk.type ||
1060 k1->rk.rrset_class != k2->rk.rrset_class ||
1061 query_dname_compare(k1->rk.dname, k2->rk.dname) != 0)
1062 return 0;
1063 if( /* do not check ttl: d1->ttl != d2->ttl || */
1064 d1->count != d2->count ||
1065 d1->rrsig_count != d2->rrsig_count ||
1066 d1->trust != d2->trust ||
1067 d1->security != d2->security)
1068 return 0;
1069 t = d1->count + d1->rrsig_count;
1070 for(i=0; i<t; i++) {
1071 if(d1->rr_len[i] != d2->rr_len[i] ||
1072 /* no ttl check: d1->rr_ttl[i] != d2->rr_ttl[i] ||*/
1073 memcmp(d1->rr_data[i], d2->rr_data[i],
1074 d1->rr_len[i]) != 0)
1075 return 0;
1076 }
1077 return 1;
1078 }
1079
1080 /** compare rrsets and sort canonically. Compares rrset name, type, class.
1081 * return 0 if equal, +1 if x > y, and -1 if x < y.
1082 */
1083 static int
rrset_canonical_sort_cmp(const void * x,const void * y)1084 rrset_canonical_sort_cmp(const void* x, const void* y)
1085 {
1086 struct ub_packed_rrset_key* rrx = *(struct ub_packed_rrset_key**)x;
1087 struct ub_packed_rrset_key* rry = *(struct ub_packed_rrset_key**)y;
1088 int r = dname_canonical_compare(rrx->rk.dname, rry->rk.dname);
1089 if(r != 0)
1090 return r;
1091 if(rrx->rk.type != rry->rk.type) {
1092 if(ntohs(rrx->rk.type) > ntohs(rry->rk.type))
1093 return 1;
1094 else return -1;
1095 }
1096 if(rrx->rk.rrset_class != rry->rk.rrset_class) {
1097 if(ntohs(rrx->rk.rrset_class) > ntohs(rry->rk.rrset_class))
1098 return 1;
1099 else return -1;
1100 }
1101 return 0;
1102 }
1103
1104 int
reply_equal(struct reply_info * p,struct reply_info * q,struct regional * region)1105 reply_equal(struct reply_info* p, struct reply_info* q, struct regional* region)
1106 {
1107 size_t i;
1108 struct ub_packed_rrset_key** sorted_p, **sorted_q;
1109 if(p->flags != q->flags ||
1110 p->qdcount != q->qdcount ||
1111 /* do not check TTL, this may differ */
1112 /*
1113 p->ttl != q->ttl ||
1114 p->prefetch_ttl != q->prefetch_ttl ||
1115 */
1116 p->security != q->security ||
1117 p->an_numrrsets != q->an_numrrsets ||
1118 p->ns_numrrsets != q->ns_numrrsets ||
1119 p->ar_numrrsets != q->ar_numrrsets ||
1120 p->rrset_count != q->rrset_count)
1121 return 0;
1122 /* sort the rrsets in the authority and additional sections before
1123 * compare, the query and answer sections are ordered in the sequence
1124 * they should have (eg. one after the other for aliases). */
1125 sorted_p = (struct ub_packed_rrset_key**)regional_alloc_init(
1126 region, p->rrsets, sizeof(*sorted_p)*p->rrset_count);
1127 if(!sorted_p) return 0;
1128 log_assert(p->an_numrrsets + p->ns_numrrsets + p->ar_numrrsets <=
1129 p->rrset_count);
1130 qsort(sorted_p + p->an_numrrsets, p->ns_numrrsets,
1131 sizeof(*sorted_p), rrset_canonical_sort_cmp);
1132 qsort(sorted_p + p->an_numrrsets + p->ns_numrrsets, p->ar_numrrsets,
1133 sizeof(*sorted_p), rrset_canonical_sort_cmp);
1134
1135 sorted_q = (struct ub_packed_rrset_key**)regional_alloc_init(
1136 region, q->rrsets, sizeof(*sorted_q)*q->rrset_count);
1137 if(!sorted_q) {
1138 regional_free_all(region);
1139 return 0;
1140 }
1141 log_assert(q->an_numrrsets + q->ns_numrrsets + q->ar_numrrsets <=
1142 q->rrset_count);
1143 qsort(sorted_q + q->an_numrrsets, q->ns_numrrsets,
1144 sizeof(*sorted_q), rrset_canonical_sort_cmp);
1145 qsort(sorted_q + q->an_numrrsets + q->ns_numrrsets, q->ar_numrrsets,
1146 sizeof(*sorted_q), rrset_canonical_sort_cmp);
1147
1148 /* compare the rrsets */
1149 for(i=0; i<p->rrset_count; i++) {
1150 if(!rrset_equal(sorted_p[i], sorted_q[i])) {
1151 if(!rrset_canonical_equal(region, sorted_p[i],
1152 sorted_q[i])) {
1153 regional_free_all(region);
1154 return 0;
1155 }
1156 }
1157 }
1158 regional_free_all(region);
1159 return 1;
1160 }
1161
1162 void
caps_strip_reply(struct reply_info * rep)1163 caps_strip_reply(struct reply_info* rep)
1164 {
1165 size_t i;
1166 if(!rep) return;
1167 /* see if message is a referral, in which case the additional and
1168 * NS record cannot be removed */
1169 /* referrals have the AA flag unset (strict check, not elsewhere in
1170 * unbound, but for 0x20 this is very convenient). */
1171 if(!(rep->flags&BIT_AA))
1172 return;
1173 /* remove the additional section from the reply */
1174 if(rep->ar_numrrsets != 0) {
1175 verbose(VERB_ALGO, "caps fallback: removing additional section");
1176 rep->rrset_count -= rep->ar_numrrsets;
1177 rep->ar_numrrsets = 0;
1178 }
1179 /* is there an NS set in the authority section to remove? */
1180 /* the failure case (Cisco firewalls) only has one rrset in authsec */
1181 for(i=rep->an_numrrsets; i<rep->an_numrrsets+rep->ns_numrrsets; i++) {
1182 struct ub_packed_rrset_key* s = rep->rrsets[i];
1183 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NS) {
1184 /* remove NS rrset and break from loop (loop limits
1185 * have changed) */
1186 /* move last rrset into this position (there is no
1187 * additional section any more) */
1188 verbose(VERB_ALGO, "caps fallback: removing NS rrset");
1189 if(i < rep->rrset_count-1)
1190 rep->rrsets[i]=rep->rrsets[rep->rrset_count-1];
1191 rep->rrset_count --;
1192 rep->ns_numrrsets --;
1193 break;
1194 }
1195 }
1196 }
1197
caps_failed_rcode(struct reply_info * rep)1198 int caps_failed_rcode(struct reply_info* rep)
1199 {
1200 return !(FLAGS_GET_RCODE(rep->flags) == LDNS_RCODE_NOERROR ||
1201 FLAGS_GET_RCODE(rep->flags) == LDNS_RCODE_NXDOMAIN);
1202 }
1203
1204 void
iter_store_parentside_rrset(struct module_env * env,struct ub_packed_rrset_key * rrset)1205 iter_store_parentside_rrset(struct module_env* env,
1206 struct ub_packed_rrset_key* rrset)
1207 {
1208 struct rrset_ref ref;
1209 rrset = packed_rrset_copy_alloc(rrset, env->alloc, *env->now);
1210 if(!rrset) {
1211 log_err("malloc failure in store_parentside_rrset");
1212 return;
1213 }
1214 rrset->rk.flags |= PACKED_RRSET_PARENT_SIDE;
1215 rrset->entry.hash = rrset_key_hash(&rrset->rk);
1216 ref.key = rrset;
1217 ref.id = rrset->id;
1218 /* ignore ret: if it was in the cache, ref updated */
1219 (void)rrset_cache_update(env->rrset_cache, &ref, env->alloc, *env->now);
1220 }
1221
1222 /** fetch NS record from reply, if any */
1223 static struct ub_packed_rrset_key*
reply_get_NS_rrset(struct reply_info * rep)1224 reply_get_NS_rrset(struct reply_info* rep)
1225 {
1226 size_t i;
1227 for(i=0; i<rep->rrset_count; i++) {
1228 if(rep->rrsets[i]->rk.type == htons(LDNS_RR_TYPE_NS)) {
1229 return rep->rrsets[i];
1230 }
1231 }
1232 return NULL;
1233 }
1234
1235 void
iter_store_parentside_NS(struct module_env * env,struct reply_info * rep)1236 iter_store_parentside_NS(struct module_env* env, struct reply_info* rep)
1237 {
1238 struct ub_packed_rrset_key* rrset = reply_get_NS_rrset(rep);
1239 if(rrset) {
1240 log_rrset_key(VERB_ALGO, "store parent-side NS", rrset);
1241 iter_store_parentside_rrset(env, rrset);
1242 }
1243 }
1244
iter_store_parentside_neg(struct module_env * env,struct query_info * qinfo,struct reply_info * rep)1245 void iter_store_parentside_neg(struct module_env* env,
1246 struct query_info* qinfo, struct reply_info* rep)
1247 {
1248 /* TTL: NS from referral in iq->deleg_msg,
1249 * or first RR from iq->response,
1250 * or servfail5secs if !iq->response */
1251 time_t ttl = NORR_TTL;
1252 struct ub_packed_rrset_key* neg;
1253 struct packed_rrset_data* newd;
1254 if(rep) {
1255 struct ub_packed_rrset_key* rrset = reply_get_NS_rrset(rep);
1256 if(!rrset && rep->rrset_count != 0) rrset = rep->rrsets[0];
1257 if(rrset) ttl = ub_packed_rrset_ttl(rrset);
1258 }
1259 /* create empty rrset to store */
1260 neg = (struct ub_packed_rrset_key*)regional_alloc(env->scratch,
1261 sizeof(struct ub_packed_rrset_key));
1262 if(!neg) {
1263 log_err("out of memory in store_parentside_neg");
1264 return;
1265 }
1266 memset(&neg->entry, 0, sizeof(neg->entry));
1267 neg->entry.key = neg;
1268 neg->rk.type = htons(qinfo->qtype);
1269 neg->rk.rrset_class = htons(qinfo->qclass);
1270 neg->rk.flags = 0;
1271 neg->rk.dname = regional_alloc_init(env->scratch, qinfo->qname,
1272 qinfo->qname_len);
1273 if(!neg->rk.dname) {
1274 log_err("out of memory in store_parentside_neg");
1275 return;
1276 }
1277 neg->rk.dname_len = qinfo->qname_len;
1278 neg->entry.hash = rrset_key_hash(&neg->rk);
1279 newd = (struct packed_rrset_data*)regional_alloc_zero(env->scratch,
1280 sizeof(struct packed_rrset_data) + sizeof(size_t) +
1281 sizeof(uint8_t*) + sizeof(time_t) + sizeof(uint16_t));
1282 if(!newd) {
1283 log_err("out of memory in store_parentside_neg");
1284 return;
1285 }
1286 neg->entry.data = newd;
1287 newd->ttl = ttl;
1288 /* entry must have one RR, otherwise not valid in cache.
1289 * put in one RR with empty rdata: those are ignored as nameserver */
1290 newd->count = 1;
1291 newd->rrsig_count = 0;
1292 newd->trust = rrset_trust_ans_noAA;
1293 newd->rr_len = (size_t*)((uint8_t*)newd +
1294 sizeof(struct packed_rrset_data));
1295 newd->rr_len[0] = 0 /* zero len rdata */ + sizeof(uint16_t);
1296 packed_rrset_ptr_fixup(newd);
1297 newd->rr_ttl[0] = newd->ttl;
1298 sldns_write_uint16(newd->rr_data[0], 0 /* zero len rdata */);
1299 /* store it */
1300 log_rrset_key(VERB_ALGO, "store parent-side negative", neg);
1301 iter_store_parentside_rrset(env, neg);
1302 }
1303
1304 int
iter_lookup_parent_NS_from_cache(struct module_env * env,struct delegpt * dp,struct regional * region,struct query_info * qinfo)1305 iter_lookup_parent_NS_from_cache(struct module_env* env, struct delegpt* dp,
1306 struct regional* region, struct query_info* qinfo)
1307 {
1308 struct ub_packed_rrset_key* akey;
1309 akey = rrset_cache_lookup(env->rrset_cache, dp->name,
1310 dp->namelen, LDNS_RR_TYPE_NS, qinfo->qclass,
1311 PACKED_RRSET_PARENT_SIDE, *env->now, 0);
1312 if(akey) {
1313 log_rrset_key(VERB_ALGO, "found parent-side NS in cache", akey);
1314 dp->has_parent_side_NS = 1;
1315 /* and mark the new names as lame */
1316 if(!delegpt_rrset_add_ns(dp, region, akey, 1)) {
1317 lock_rw_unlock(&akey->entry.lock);
1318 return 0;
1319 }
1320 lock_rw_unlock(&akey->entry.lock);
1321 }
1322 return 1;
1323 }
1324
iter_lookup_parent_glue_from_cache(struct module_env * env,struct delegpt * dp,struct regional * region,struct query_info * qinfo)1325 int iter_lookup_parent_glue_from_cache(struct module_env* env,
1326 struct delegpt* dp, struct regional* region, struct query_info* qinfo)
1327 {
1328 struct ub_packed_rrset_key* akey;
1329 struct delegpt_ns* ns;
1330 size_t num = delegpt_count_targets(dp);
1331 for(ns = dp->nslist; ns; ns = ns->next) {
1332 if(ns->cache_lookup_count > ITERATOR_NAME_CACHELOOKUP_MAX_PSIDE)
1333 continue;
1334 ns->cache_lookup_count++;
1335 /* get cached parentside A */
1336 akey = rrset_cache_lookup(env->rrset_cache, ns->name,
1337 ns->namelen, LDNS_RR_TYPE_A, qinfo->qclass,
1338 PACKED_RRSET_PARENT_SIDE, *env->now, 0);
1339 if(akey) {
1340 log_rrset_key(VERB_ALGO, "found parent-side", akey);
1341 ns->done_pside4 = 1;
1342 /* a negative-cache-element has no addresses it adds */
1343 if(!delegpt_add_rrset_A(dp, region, akey, 1, NULL))
1344 log_err("malloc failure in lookup_parent_glue");
1345 lock_rw_unlock(&akey->entry.lock);
1346 }
1347 /* get cached parentside AAAA */
1348 akey = rrset_cache_lookup(env->rrset_cache, ns->name,
1349 ns->namelen, LDNS_RR_TYPE_AAAA, qinfo->qclass,
1350 PACKED_RRSET_PARENT_SIDE, *env->now, 0);
1351 if(akey) {
1352 log_rrset_key(VERB_ALGO, "found parent-side", akey);
1353 ns->done_pside6 = 1;
1354 /* a negative-cache-element has no addresses it adds */
1355 if(!delegpt_add_rrset_AAAA(dp, region, akey, 1, NULL))
1356 log_err("malloc failure in lookup_parent_glue");
1357 lock_rw_unlock(&akey->entry.lock);
1358 }
1359 }
1360 /* see if new (but lame) addresses have become available */
1361 return delegpt_count_targets(dp) != num;
1362 }
1363
1364 int
iter_get_next_root(struct iter_hints * hints,struct iter_forwards * fwd,uint16_t * c)1365 iter_get_next_root(struct iter_hints* hints, struct iter_forwards* fwd,
1366 uint16_t* c)
1367 {
1368 uint16_t c1 = *c, c2 = *c;
1369 int r1, r2;
1370 int nolock = 1;
1371
1372 /* prelock both forwards and hints for atomic read. */
1373 lock_rw_rdlock(&fwd->lock);
1374 lock_rw_rdlock(&hints->lock);
1375 r1 = hints_next_root(hints, &c1, nolock);
1376 r2 = forwards_next_root(fwd, &c2, nolock);
1377 lock_rw_unlock(&fwd->lock);
1378 lock_rw_unlock(&hints->lock);
1379
1380 if(!r1 && !r2) /* got none, end of list */
1381 return 0;
1382 else if(!r1) /* got one, return that */
1383 *c = c2;
1384 else if(!r2)
1385 *c = c1;
1386 else if(c1 < c2) /* got both take smallest */
1387 *c = c1;
1388 else *c = c2;
1389 return 1;
1390 }
1391
1392 void
iter_scrub_ds(struct dns_msg * msg,struct ub_packed_rrset_key * ns,uint8_t * z)1393 iter_scrub_ds(struct dns_msg* msg, struct ub_packed_rrset_key* ns, uint8_t* z)
1394 {
1395 /* Only the DS record for the delegation itself is expected.
1396 * We allow DS for everything between the bailiwick and the
1397 * zonecut, thus DS records must be at or above the zonecut.
1398 * And the DS records must be below the server authority zone.
1399 * The answer section is already scrubbed. */
1400 size_t i = msg->rep->an_numrrsets;
1401 while(i < (msg->rep->an_numrrsets + msg->rep->ns_numrrsets)) {
1402 struct ub_packed_rrset_key* s = msg->rep->rrsets[i];
1403 if(ntohs(s->rk.type) == LDNS_RR_TYPE_DS &&
1404 (!ns || !dname_subdomain_c(ns->rk.dname, s->rk.dname)
1405 || query_dname_compare(z, s->rk.dname) == 0)) {
1406 log_nametypeclass(VERB_ALGO, "removing irrelevant DS",
1407 s->rk.dname, ntohs(s->rk.type),
1408 ntohs(s->rk.rrset_class));
1409 memmove(msg->rep->rrsets+i, msg->rep->rrsets+i+1,
1410 sizeof(struct ub_packed_rrset_key*) *
1411 (msg->rep->rrset_count-i-1));
1412 msg->rep->ns_numrrsets--;
1413 msg->rep->rrset_count--;
1414 /* stay at same i, but new record */
1415 continue;
1416 }
1417 i++;
1418 }
1419 }
1420
1421 void
iter_scrub_nxdomain(struct dns_msg * msg)1422 iter_scrub_nxdomain(struct dns_msg* msg)
1423 {
1424 if(msg->rep->an_numrrsets == 0)
1425 return;
1426
1427 memmove(msg->rep->rrsets, msg->rep->rrsets+msg->rep->an_numrrsets,
1428 sizeof(struct ub_packed_rrset_key*) *
1429 (msg->rep->rrset_count-msg->rep->an_numrrsets));
1430 msg->rep->rrset_count -= msg->rep->an_numrrsets;
1431 msg->rep->an_numrrsets = 0;
1432 }
1433
iter_dec_attempts(struct delegpt * dp,int d,int outbound_msg_retry)1434 void iter_dec_attempts(struct delegpt* dp, int d, int outbound_msg_retry)
1435 {
1436 struct delegpt_addr* a;
1437 for(a=dp->target_list; a; a = a->next_target) {
1438 if(a->attempts >= outbound_msg_retry) {
1439 /* add back to result list */
1440 delegpt_add_to_result_list(dp, a);
1441 }
1442 if(a->attempts > d)
1443 a->attempts -= d;
1444 else a->attempts = 0;
1445 }
1446 }
1447
iter_merge_retry_counts(struct delegpt * dp,struct delegpt * old,int outbound_msg_retry)1448 void iter_merge_retry_counts(struct delegpt* dp, struct delegpt* old,
1449 int outbound_msg_retry)
1450 {
1451 struct delegpt_addr* a, *o, *prev;
1452 for(a=dp->target_list; a; a = a->next_target) {
1453 o = delegpt_find_addr(old, &a->addr, a->addrlen);
1454 if(o) {
1455 log_addr(VERB_ALGO, "copy attempt count previous dp",
1456 &a->addr, a->addrlen);
1457 a->attempts = o->attempts;
1458 }
1459 }
1460 prev = NULL;
1461 a = dp->usable_list;
1462 while(a) {
1463 if(a->attempts >= outbound_msg_retry) {
1464 log_addr(VERB_ALGO, "remove from usable list dp",
1465 &a->addr, a->addrlen);
1466 /* remove from result list */
1467 if(prev)
1468 prev->next_usable = a->next_usable;
1469 else dp->usable_list = a->next_usable;
1470 /* prev stays the same */
1471 a = a->next_usable;
1472 continue;
1473 }
1474 prev = a;
1475 a = a->next_usable;
1476 }
1477 }
1478
1479 int
iter_ds_toolow(struct dns_msg * msg,struct delegpt * dp)1480 iter_ds_toolow(struct dns_msg* msg, struct delegpt* dp)
1481 {
1482 /* if for query example.com, there is example.com SOA or a subdomain
1483 * of example.com, then we are too low and need to fetch NS. */
1484 size_t i;
1485 /* if we have a DNAME or CNAME we are probably wrong */
1486 /* if we have a qtype DS in the answer section, its fine */
1487 for(i=0; i < msg->rep->an_numrrsets; i++) {
1488 struct ub_packed_rrset_key* s = msg->rep->rrsets[i];
1489 if(ntohs(s->rk.type) == LDNS_RR_TYPE_DNAME ||
1490 ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME) {
1491 /* not the right answer, maybe too low, check the
1492 * RRSIG signer name (if there is any) for a hint
1493 * that it is from the dp zone anyway */
1494 uint8_t* sname;
1495 size_t slen;
1496 val_find_rrset_signer(s, &sname, &slen);
1497 if(sname && query_dname_compare(dp->name, sname)==0)
1498 return 0; /* it is fine, from the right dp */
1499 return 1;
1500 }
1501 if(ntohs(s->rk.type) == LDNS_RR_TYPE_DS)
1502 return 0; /* fine, we have a DS record */
1503 }
1504 for(i=msg->rep->an_numrrsets;
1505 i < msg->rep->an_numrrsets + msg->rep->ns_numrrsets; i++) {
1506 struct ub_packed_rrset_key* s = msg->rep->rrsets[i];
1507 if(ntohs(s->rk.type) == LDNS_RR_TYPE_SOA) {
1508 if(dname_subdomain_c(s->rk.dname, msg->qinfo.qname))
1509 return 1; /* point is too low */
1510 if(query_dname_compare(s->rk.dname, dp->name)==0)
1511 return 0; /* right dp */
1512 }
1513 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC ||
1514 ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) {
1515 uint8_t* sname;
1516 size_t slen;
1517 val_find_rrset_signer(s, &sname, &slen);
1518 if(sname && query_dname_compare(dp->name, sname)==0)
1519 return 0; /* it is fine, from the right dp */
1520 return 1;
1521 }
1522 }
1523 /* we do not know */
1524 return 1;
1525 }
1526
iter_dp_cangodown(struct query_info * qinfo,struct delegpt * dp)1527 int iter_dp_cangodown(struct query_info* qinfo, struct delegpt* dp)
1528 {
1529 /* no delegation point, do not see how we can go down,
1530 * robust check, it should really exist */
1531 if(!dp) return 0;
1532
1533 /* see if dp equals the qname, then we cannot go down further */
1534 if(query_dname_compare(qinfo->qname, dp->name) == 0)
1535 return 0;
1536 /* if dp is one label above the name we also cannot go down further */
1537 if(dname_count_labels(qinfo->qname) == dp->namelabs+1)
1538 return 0;
1539 return 1;
1540 }
1541
1542 int
iter_stub_fwd_no_cache(struct module_qstate * qstate,struct query_info * qinf,uint8_t ** retdpname,size_t * retdpnamelen,uint8_t * dpname_storage,size_t dpname_storage_len)1543 iter_stub_fwd_no_cache(struct module_qstate *qstate, struct query_info *qinf,
1544 uint8_t** retdpname, size_t* retdpnamelen, uint8_t* dpname_storage,
1545 size_t dpname_storage_len)
1546 {
1547 struct iter_hints_stub *stub;
1548 struct delegpt *dp;
1549 int nolock = 1;
1550
1551 log_assert((retdpname && retdpnamelen
1552 && dpname_storage && dpname_storage_len > 0) ||
1553 (retdpname == NULL && retdpnamelen == NULL
1554 && dpname_storage == NULL && dpname_storage_len == 0));
1555
1556 /* Check for stub. */
1557 /* Lock both forwards and hints for atomic read. */
1558 lock_rw_rdlock(&qstate->env->fwds->lock);
1559 lock_rw_rdlock(&qstate->env->hints->lock);
1560 stub = hints_lookup_stub(qstate->env->hints, qinf->qname,
1561 qinf->qclass, NULL, nolock);
1562 dp = forwards_lookup(qstate->env->fwds, qinf->qname, qinf->qclass,
1563 nolock);
1564
1565 /* see if forward or stub is more pertinent */
1566 if(stub && stub->dp && dp) {
1567 if(dname_strict_subdomain(dp->name, dp->namelabs,
1568 stub->dp->name, stub->dp->namelabs)) {
1569 stub = NULL; /* ignore stub, forward is lower */
1570 } else {
1571 dp = NULL; /* ignore forward, stub is lower */
1572 }
1573 }
1574
1575 /* check stub */
1576 if (stub != NULL && stub->dp != NULL) {
1577 enum verbosity_value level = VERB_ALGO;
1578 int stub_no_cache = stub->dp->no_cache;
1579 lock_rw_unlock(&qstate->env->fwds->lock);
1580 if(verbosity >= level && stub_no_cache) {
1581 char qname[LDNS_MAX_DOMAINLEN];
1582 char dpname[LDNS_MAX_DOMAINLEN];
1583 dname_str(qinf->qname, qname);
1584 dname_str(stub->dp->name, dpname);
1585 verbose(level, "stub for %s %s has no_cache", qname, dpname);
1586 }
1587 if(retdpname) {
1588 if(stub->dp->namelen > dpname_storage_len) {
1589 verbose(VERB_ALGO, "no cache stub dpname too long");
1590 lock_rw_unlock(&qstate->env->hints->lock);
1591 *retdpname = NULL;
1592 *retdpnamelen = 0;
1593 return stub_no_cache;
1594 }
1595 memmove(dpname_storage, stub->dp->name,
1596 stub->dp->namelen);
1597 *retdpname = dpname_storage;
1598 *retdpnamelen = stub->dp->namelen;
1599 }
1600 lock_rw_unlock(&qstate->env->hints->lock);
1601 return stub_no_cache;
1602 }
1603
1604 /* Check for forward. */
1605 if (dp) {
1606 enum verbosity_value level = VERB_ALGO;
1607 int dp_no_cache = dp->no_cache;
1608 lock_rw_unlock(&qstate->env->hints->lock);
1609 if(verbosity >= level && dp_no_cache) {
1610 char qname[LDNS_MAX_DOMAINLEN];
1611 char dpname[LDNS_MAX_DOMAINLEN];
1612 dname_str(qinf->qname, qname);
1613 dname_str(dp->name, dpname);
1614 verbose(level, "forward for %s %s has no_cache", qname, dpname);
1615 }
1616 if(retdpname) {
1617 if(dp->namelen > dpname_storage_len) {
1618 verbose(VERB_ALGO, "no cache dpname too long");
1619 lock_rw_unlock(&qstate->env->fwds->lock);
1620 *retdpname = NULL;
1621 *retdpnamelen = 0;
1622 return dp_no_cache;
1623 }
1624 memmove(dpname_storage, dp->name, dp->namelen);
1625 *retdpname = dpname_storage;
1626 *retdpnamelen = dp->namelen;
1627 }
1628 lock_rw_unlock(&qstate->env->fwds->lock);
1629 return dp_no_cache;
1630 }
1631 lock_rw_unlock(&qstate->env->fwds->lock);
1632 lock_rw_unlock(&qstate->env->hints->lock);
1633 if(retdpname) {
1634 *retdpname = NULL;
1635 *retdpnamelen = 0;
1636 }
1637 return 0;
1638 }
1639
iterator_set_ip46_support(struct module_stack * mods,struct module_env * env,struct outside_network * outnet)1640 void iterator_set_ip46_support(struct module_stack* mods,
1641 struct module_env* env, struct outside_network* outnet)
1642 {
1643 int m = modstack_find(mods, "iterator");
1644 struct iter_env* ie = NULL;
1645 if(m == -1)
1646 return;
1647 ie = (struct iter_env*)env->modinfo[m];
1648 if(outnet->pending == NULL)
1649 return; /* we are in testbound, no rbtree for UDP */
1650 if(outnet->num_ip4 == 0)
1651 ie->supports_ipv4 = 0;
1652 if(outnet->num_ip6 == 0)
1653 ie->supports_ipv6 = 0;
1654 }
1655
1656 void
limit_nsec_ttl(struct dns_msg * msg)1657 limit_nsec_ttl(struct dns_msg* msg)
1658 {
1659 /* Limit NSEC and NSEC3 TTL in response, RFC9077 */
1660 size_t i;
1661 int found = 0;
1662 time_t soa_ttl = 0;
1663 /* Limit the NSEC and NSEC3 TTL values to the SOA TTL and SOA minimum
1664 * TTL. That has already been applied to the SOA record ttl. */
1665 for(i=0; i<msg->rep->rrset_count; i++) {
1666 struct ub_packed_rrset_key* s = msg->rep->rrsets[i];
1667 if(ntohs(s->rk.type) == LDNS_RR_TYPE_SOA) {
1668 struct packed_rrset_data* soadata = (struct packed_rrset_data*)s->entry.data;
1669 found = 1;
1670 soa_ttl = soadata->ttl;
1671 break;
1672 }
1673 }
1674 if(!found)
1675 return;
1676 for(i=0; i<msg->rep->rrset_count; i++) {
1677 struct ub_packed_rrset_key* s = msg->rep->rrsets[i];
1678 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC ||
1679 ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) {
1680 struct packed_rrset_data* data = (struct packed_rrset_data*)s->entry.data;
1681 /* Limit the negative TTL. */
1682 if(data->ttl > soa_ttl) {
1683 if(verbosity >= VERB_ALGO) {
1684 char buf[256];
1685 snprintf(buf, sizeof(buf),
1686 "limiting TTL %d of %s record to the SOA TTL of %d for",
1687 (int)data->ttl, ((ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC)?"NSEC":"NSEC3"), (int)soa_ttl);
1688 log_nametypeclass(VERB_ALGO, buf,
1689 s->rk.dname, ntohs(s->rk.type),
1690 ntohs(s->rk.rrset_class));
1691 }
1692 data->ttl = soa_ttl;
1693 }
1694 }
1695 }
1696 }
1697
1698 void
iter_make_minimal(struct reply_info * rep)1699 iter_make_minimal(struct reply_info* rep)
1700 {
1701 size_t rem = rep->ns_numrrsets + rep->ar_numrrsets;
1702 rep->ns_numrrsets = 0;
1703 rep->ar_numrrsets = 0;
1704 rep->rrset_count -= rem;
1705 }
1706