1 /*
2 * validator/validator.c - secure validator DNS query response module
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 a module that performs validation of DNS queries.
40 * According to RFC 4034.
41 */
42 #include "config.h"
43 #include <ctype.h>
44 #include "validator/validator.h"
45 #include "validator/val_anchor.h"
46 #include "validator/val_kcache.h"
47 #include "validator/val_kentry.h"
48 #include "validator/val_utils.h"
49 #include "validator/val_nsec.h"
50 #include "validator/val_nsec3.h"
51 #include "validator/val_neg.h"
52 #include "validator/val_sigcrypt.h"
53 #include "validator/autotrust.h"
54 #include "services/cache/dns.h"
55 #include "services/cache/rrset.h"
56 #include "util/data/dname.h"
57 #include "util/module.h"
58 #include "util/log.h"
59 #include "util/net_help.h"
60 #include "util/regional.h"
61 #include "util/config_file.h"
62 #include "util/fptr_wlist.h"
63 #include "sldns/rrdef.h"
64 #include "sldns/wire2str.h"
65 #include "sldns/str2wire.h"
66
67 /** Max number of RRSIGs to validate at once, suspend query for later. */
68 #define MAX_VALIDATE_AT_ONCE 8
69 /** Max number of validation suspends allowed, error out otherwise. */
70 #define MAX_VALIDATION_SUSPENDS 16
71
72 /* forward decl for cache response and normal super inform calls of a DS */
73 static void process_ds_response(struct module_qstate* qstate,
74 struct val_qstate* vq, int id, int rcode, struct dns_msg* msg,
75 struct query_info* qinfo, struct sock_list* origin, int* suspend,
76 struct module_qstate* sub_qstate);
77
78
79 /* Updates the suplied EDE (RFC8914) code selectively so we don't lose
80 * a more specific code */
81 static void
update_reason_bogus(struct reply_info * rep,sldns_ede_code reason_bogus)82 update_reason_bogus(struct reply_info* rep, sldns_ede_code reason_bogus)
83 {
84 if(reason_bogus == LDNS_EDE_NONE) return;
85 if(reason_bogus == LDNS_EDE_DNSSEC_BOGUS
86 && rep->reason_bogus != LDNS_EDE_NONE
87 && rep->reason_bogus != LDNS_EDE_DNSSEC_BOGUS) return;
88 rep->reason_bogus = reason_bogus;
89 }
90
91
92 /** fill up nsec3 key iterations config entry */
93 static int
fill_nsec3_iter(struct val_env * ve,char * s,int c)94 fill_nsec3_iter(struct val_env* ve, char* s, int c)
95 {
96 char* e;
97 int i;
98 free(ve->nsec3_keysize);
99 free(ve->nsec3_maxiter);
100 ve->nsec3_keysize = (size_t*)calloc((size_t)c, sizeof(size_t));
101 ve->nsec3_maxiter = (size_t*)calloc((size_t)c, sizeof(size_t));
102 if(!ve->nsec3_keysize || !ve->nsec3_maxiter) {
103 log_err("out of memory");
104 return 0;
105 }
106 for(i=0; i<c; i++) {
107 ve->nsec3_keysize[i] = (size_t)strtol(s, &e, 10);
108 if(s == e) {
109 log_err("cannot parse: %s", s);
110 return 0;
111 }
112 s = e;
113 ve->nsec3_maxiter[i] = (size_t)strtol(s, &e, 10);
114 if(s == e) {
115 log_err("cannot parse: %s", s);
116 return 0;
117 }
118 s = e;
119 if(i>0 && ve->nsec3_keysize[i-1] >= ve->nsec3_keysize[i]) {
120 log_err("nsec3 key iterations not ascending: %d %d",
121 (int)ve->nsec3_keysize[i-1],
122 (int)ve->nsec3_keysize[i]);
123 return 0;
124 }
125 verbose(VERB_ALGO, "validator nsec3cfg keysz %d mxiter %d",
126 (int)ve->nsec3_keysize[i], (int)ve->nsec3_maxiter[i]);
127 }
128 return 1;
129 }
130
131 /** apply config settings to validator */
132 static int
val_apply_cfg(struct module_env * env,struct val_env * val_env,struct config_file * cfg)133 val_apply_cfg(struct module_env* env, struct val_env* val_env,
134 struct config_file* cfg)
135 {
136 int c;
137 val_env->bogus_ttl = (uint32_t)cfg->bogus_ttl;
138 if(!env->anchors)
139 env->anchors = anchors_create();
140 if(!env->anchors) {
141 log_err("out of memory");
142 return 0;
143 }
144 if (env->key_cache)
145 val_env->kcache = env->key_cache;
146 if(!val_env->kcache)
147 val_env->kcache = key_cache_create(cfg);
148 if(!val_env->kcache) {
149 log_err("out of memory");
150 return 0;
151 }
152 env->key_cache = val_env->kcache;
153 if(!anchors_apply_cfg(env->anchors, cfg)) {
154 log_err("validator: error in trustanchors config");
155 return 0;
156 }
157 val_env->date_override = cfg->val_date_override;
158 val_env->skew_min = cfg->val_sig_skew_min;
159 val_env->skew_max = cfg->val_sig_skew_max;
160 val_env->max_restart = cfg->val_max_restart;
161 c = cfg_count_numbers(cfg->val_nsec3_key_iterations);
162 if(c < 1 || (c&1)) {
163 log_err("validator: unparsable or odd nsec3 key "
164 "iterations: %s", cfg->val_nsec3_key_iterations);
165 return 0;
166 }
167 val_env->nsec3_keyiter_count = c/2;
168 if(!fill_nsec3_iter(val_env, cfg->val_nsec3_key_iterations, c/2)) {
169 log_err("validator: cannot apply nsec3 key iterations");
170 return 0;
171 }
172 if (env->neg_cache)
173 val_env->neg_cache = env->neg_cache;
174 if(!val_env->neg_cache)
175 val_env->neg_cache = val_neg_create(cfg,
176 val_env->nsec3_maxiter[val_env->nsec3_keyiter_count-1]);
177 if(!val_env->neg_cache) {
178 log_err("out of memory");
179 return 0;
180 }
181 env->neg_cache = val_env->neg_cache;
182 return 1;
183 }
184
185 #ifdef USE_ECDSA_EVP_WORKAROUND
186 void ecdsa_evp_workaround_init(void);
187 #endif
188 int
val_init(struct module_env * env,int id)189 val_init(struct module_env* env, int id)
190 {
191 struct val_env* val_env = (struct val_env*)calloc(1,
192 sizeof(struct val_env));
193 if(!val_env) {
194 log_err("malloc failure");
195 return 0;
196 }
197 env->modinfo[id] = (void*)val_env;
198 env->need_to_validate = 1;
199 lock_basic_init(&val_env->bogus_lock);
200 lock_protect(&val_env->bogus_lock, &val_env->num_rrset_bogus,
201 sizeof(val_env->num_rrset_bogus));
202 #ifdef USE_ECDSA_EVP_WORKAROUND
203 ecdsa_evp_workaround_init();
204 #endif
205 if(!val_apply_cfg(env, val_env, env->cfg)) {
206 log_err("validator: could not apply configuration settings.");
207 return 0;
208 }
209 if(env->cfg->disable_edns_do) {
210 struct trust_anchor* anchor = anchors_find_any_noninsecure(
211 env->anchors);
212 if(anchor) {
213 char b[LDNS_MAX_DOMAINLEN+2];
214 dname_str(anchor->name, b);
215 log_warn("validator: disable-edns-do is enabled, but there is a trust anchor for '%s'. Since DNSSEC could not work, the disable-edns-do setting is turned off. Continuing without it.", b);
216 lock_basic_unlock(&anchor->lock);
217 env->cfg->disable_edns_do = 0;
218 }
219 }
220
221 return 1;
222 }
223
224 void
val_deinit(struct module_env * env,int id)225 val_deinit(struct module_env* env, int id)
226 {
227 struct val_env* val_env;
228 if(!env || !env->modinfo[id])
229 return;
230 val_env = (struct val_env*)env->modinfo[id];
231 lock_basic_destroy(&val_env->bogus_lock);
232 anchors_delete(env->anchors);
233 env->anchors = NULL;
234 key_cache_delete(val_env->kcache);
235 env->key_cache = NULL;
236 neg_cache_delete(val_env->neg_cache);
237 env->neg_cache = NULL;
238 free(val_env->nsec3_keysize);
239 free(val_env->nsec3_maxiter);
240 free(val_env);
241 env->modinfo[id] = NULL;
242 }
243
244 /** fill in message structure */
245 static struct val_qstate*
val_new_getmsg(struct module_qstate * qstate,struct val_qstate * vq)246 val_new_getmsg(struct module_qstate* qstate, struct val_qstate* vq)
247 {
248 if(!qstate->return_msg || qstate->return_rcode != LDNS_RCODE_NOERROR) {
249 /* create a message to verify */
250 verbose(VERB_ALGO, "constructing reply for validation");
251 vq->orig_msg = (struct dns_msg*)regional_alloc(qstate->region,
252 sizeof(struct dns_msg));
253 if(!vq->orig_msg)
254 return NULL;
255 vq->orig_msg->qinfo = qstate->qinfo;
256 vq->orig_msg->rep = (struct reply_info*)regional_alloc(
257 qstate->region, sizeof(struct reply_info));
258 if(!vq->orig_msg->rep)
259 return NULL;
260 memset(vq->orig_msg->rep, 0, sizeof(struct reply_info));
261 vq->orig_msg->rep->flags = (uint16_t)(qstate->return_rcode&0xf)
262 |BIT_QR|BIT_RA|(qstate->query_flags|(BIT_CD|BIT_RD));
263 vq->orig_msg->rep->qdcount = 1;
264 vq->orig_msg->rep->reason_bogus = LDNS_EDE_NONE;
265 } else {
266 vq->orig_msg = qstate->return_msg;
267 }
268 vq->qchase = qstate->qinfo;
269 /* chase reply will be an edited (sub)set of the orig msg rrset ptrs */
270 vq->chase_reply = regional_alloc_init(qstate->region,
271 vq->orig_msg->rep,
272 sizeof(struct reply_info) - sizeof(struct rrset_ref));
273 if(!vq->chase_reply)
274 return NULL;
275 if(vq->orig_msg->rep->rrset_count > RR_COUNT_MAX)
276 return NULL; /* protect against integer overflow */
277 /* Over allocate (+an_numrrsets) in case we need to put extra DNAME
278 * records for unsigned CNAME repetitions */
279 vq->chase_reply->rrsets = regional_alloc(qstate->region,
280 sizeof(struct ub_packed_rrset_key*) *
281 (vq->orig_msg->rep->rrset_count
282 + vq->orig_msg->rep->an_numrrsets));
283 if(!vq->chase_reply->rrsets)
284 return NULL;
285 memmove(vq->chase_reply->rrsets, vq->orig_msg->rep->rrsets,
286 sizeof(struct ub_packed_rrset_key*) *
287 vq->orig_msg->rep->rrset_count);
288 vq->rrset_skip = 0;
289 return vq;
290 }
291
292 /** allocate new validator query state */
293 static struct val_qstate*
val_new(struct module_qstate * qstate,int id)294 val_new(struct module_qstate* qstate, int id)
295 {
296 struct val_qstate* vq = (struct val_qstate*)regional_alloc(
297 qstate->region, sizeof(*vq));
298 log_assert(!qstate->minfo[id]);
299 if(!vq)
300 return NULL;
301 memset(vq, 0, sizeof(*vq));
302 qstate->minfo[id] = vq;
303 vq->state = VAL_INIT_STATE;
304 return val_new_getmsg(qstate, vq);
305 }
306
307 /** reset validator query state for query restart */
308 static void
val_restart(struct val_qstate * vq)309 val_restart(struct val_qstate* vq)
310 {
311 struct comm_timer* temp_timer;
312 int restart_count;
313 if(!vq) return;
314 temp_timer = vq->suspend_timer;
315 restart_count = vq->restart_count+1;
316 memset(vq, 0, sizeof(*vq));
317 vq->suspend_timer = temp_timer;
318 vq->restart_count = restart_count;
319 vq->state = VAL_INIT_STATE;
320 }
321
322 /**
323 * Exit validation with an error status
324 *
325 * @param qstate: query state
326 * @param id: validator id.
327 * @return false, for use by caller to return to stop processing.
328 */
329 static int
val_error(struct module_qstate * qstate,int id)330 val_error(struct module_qstate* qstate, int id)
331 {
332 qstate->ext_state[id] = module_error;
333 qstate->return_rcode = LDNS_RCODE_SERVFAIL;
334 return 0;
335 }
336
337 /**
338 * Check to see if a given response needs to go through the validation
339 * process. Typical reasons for this routine to return false are: CD bit was
340 * on in the original request, or the response is a kind of message that
341 * is unvalidatable (i.e., SERVFAIL, REFUSED, etc.)
342 *
343 * @param qstate: query state.
344 * @param ret_rc: rcode for this message (if noerror - examine ret_msg).
345 * @param ret_msg: return msg, can be NULL; look at rcode instead.
346 * @return true if the response could use validation (although this does not
347 * mean we can actually validate this response).
348 */
349 static int
needs_validation(struct module_qstate * qstate,int ret_rc,struct dns_msg * ret_msg)350 needs_validation(struct module_qstate* qstate, int ret_rc,
351 struct dns_msg* ret_msg)
352 {
353 int rcode;
354
355 /* If the CD bit is on in the original request, then you could think
356 * that we don't bother to validate anything.
357 * But this is signalled internally with the valrec flag.
358 * User queries are validated with BIT_CD to make our cache clean
359 * so that bogus messages get retried by the upstream also for
360 * downstream validators that set BIT_CD.
361 * For DNS64 bit_cd signals no dns64 processing, but we want to
362 * provide validation there too */
363 /*
364 if(qstate->query_flags & BIT_CD) {
365 verbose(VERB_ALGO, "not validating response due to CD bit");
366 return 0;
367 }
368 */
369 if(qstate->is_valrec) {
370 verbose(VERB_ALGO, "not validating response, is valrec"
371 "(validation recursion lookup)");
372 return 0;
373 }
374
375 if(ret_rc != LDNS_RCODE_NOERROR || !ret_msg)
376 rcode = ret_rc;
377 else rcode = (int)FLAGS_GET_RCODE(ret_msg->rep->flags);
378
379 if(rcode != LDNS_RCODE_NOERROR && rcode != LDNS_RCODE_NXDOMAIN) {
380 if(verbosity >= VERB_ALGO) {
381 char rc[16];
382 rc[0]=0;
383 (void)sldns_wire2str_rcode_buf(rcode, rc, sizeof(rc));
384 verbose(VERB_ALGO, "cannot validate non-answer, rcode %s", rc);
385 }
386 return 0;
387 }
388
389 /* cannot validate positive RRSIG response. (negatives can) */
390 if(qstate->qinfo.qtype == LDNS_RR_TYPE_RRSIG &&
391 rcode == LDNS_RCODE_NOERROR && ret_msg &&
392 ret_msg->rep->an_numrrsets > 0) {
393 verbose(VERB_ALGO, "cannot validate RRSIG, no sigs on sigs.");
394 return 0;
395 }
396 return 1;
397 }
398
399 /**
400 * Check to see if the response has already been validated.
401 * @param ret_msg: return msg, can be NULL
402 * @return true if the response has already been validated
403 */
404 static int
already_validated(struct dns_msg * ret_msg)405 already_validated(struct dns_msg* ret_msg)
406 {
407 /* validate unchecked, and re-validate bogus messages */
408 if (ret_msg && ret_msg->rep->security > sec_status_bogus)
409 {
410 verbose(VERB_ALGO, "response has already been validated: %s",
411 sec_status_to_string(ret_msg->rep->security));
412 return 1;
413 }
414 return 0;
415 }
416
417 /**
418 * Generate a request for DNS data.
419 *
420 * @param qstate: query state that is the parent.
421 * @param id: module id.
422 * @param name: what name to query for.
423 * @param namelen: length of name.
424 * @param qtype: query type.
425 * @param qclass: query class.
426 * @param flags: additional flags, such as the CD bit (BIT_CD), or 0.
427 * @param newq: If the subquery is newly created, it is returned,
428 * otherwise NULL is returned
429 * @param detached: true if this qstate should not attach to the subquery
430 * @return false on alloc failure.
431 */
432 static int
generate_request(struct module_qstate * qstate,int id,uint8_t * name,size_t namelen,uint16_t qtype,uint16_t qclass,uint16_t flags,struct module_qstate ** newq,int detached)433 generate_request(struct module_qstate* qstate, int id, uint8_t* name,
434 size_t namelen, uint16_t qtype, uint16_t qclass, uint16_t flags,
435 struct module_qstate** newq, int detached)
436 {
437 struct val_qstate* vq = (struct val_qstate*)qstate->minfo[id];
438 struct query_info ask;
439 int valrec;
440 ask.qname = name;
441 ask.qname_len = namelen;
442 ask.qtype = qtype;
443 ask.qclass = qclass;
444 ask.local_alias = NULL;
445 log_query_info(VERB_ALGO, "generate request", &ask);
446 /* enable valrec flag to avoid recursion to the same validation
447 * routine, this lookup is simply a lookup. */
448 valrec = 1;
449
450 fptr_ok(fptr_whitelist_modenv_detect_cycle(qstate->env->detect_cycle));
451 if((*qstate->env->detect_cycle)(qstate, &ask,
452 (uint16_t)(BIT_RD|flags), 0, valrec)) {
453 verbose(VERB_ALGO, "Could not generate request: cycle detected");
454 return 0;
455 }
456
457 if(detached) {
458 struct mesh_state* sub = NULL;
459 fptr_ok(fptr_whitelist_modenv_add_sub(
460 qstate->env->add_sub));
461 if(!(*qstate->env->add_sub)(qstate, &ask,
462 (uint16_t)(BIT_RD|flags), 0, valrec, newq, &sub)){
463 log_err("Could not generate request: out of memory");
464 return 0;
465 }
466 }
467 else {
468 fptr_ok(fptr_whitelist_modenv_attach_sub(
469 qstate->env->attach_sub));
470 if(!(*qstate->env->attach_sub)(qstate, &ask,
471 (uint16_t)(BIT_RD|flags), 0, valrec, newq)){
472 log_err("Could not generate request: out of memory");
473 return 0;
474 }
475 }
476 /* newq; validator does not need state created for that
477 * query, and its a 'normal' for iterator as well */
478 if(*newq) {
479 /* add our blacklist to the query blacklist */
480 sock_list_merge(&(*newq)->blacklist, (*newq)->region,
481 vq->chain_blacklist);
482 }
483 qstate->ext_state[id] = module_wait_subquery;
484 return 1;
485 }
486
487 /**
488 * Generate, send and detach key tag signaling query.
489 *
490 * @param qstate: query state.
491 * @param id: module id.
492 * @param ta: trust anchor, locked.
493 * @return false on a processing error.
494 */
495 static int
generate_keytag_query(struct module_qstate * qstate,int id,struct trust_anchor * ta)496 generate_keytag_query(struct module_qstate* qstate, int id,
497 struct trust_anchor* ta)
498 {
499 /* 3 bytes for "_ta", 5 bytes per tag (4 bytes + "-") */
500 #define MAX_LABEL_TAGS (LDNS_MAX_LABELLEN-3)/5
501 size_t i, numtag;
502 uint16_t tags[MAX_LABEL_TAGS];
503 char tagstr[LDNS_MAX_LABELLEN+1] = "_ta"; /* +1 for NULL byte */
504 size_t tagstr_left = sizeof(tagstr) - strlen(tagstr);
505 char* tagstr_pos = tagstr + strlen(tagstr);
506 uint8_t dnamebuf[LDNS_MAX_DOMAINLEN+1]; /* +1 for label length byte */
507 size_t dnamebuf_len = sizeof(dnamebuf);
508 uint8_t* keytagdname;
509 struct module_qstate* newq = NULL;
510 enum module_ext_state ext_state = qstate->ext_state[id];
511
512 numtag = anchor_list_keytags(ta, tags, MAX_LABEL_TAGS);
513 if(numtag == 0)
514 return 0;
515
516 for(i=0; i<numtag; i++) {
517 /* Buffer can't overflow; numtag is limited to tags that fit in
518 * the buffer. */
519 snprintf(tagstr_pos, tagstr_left, "-%04x", (unsigned)tags[i]);
520 tagstr_left -= strlen(tagstr_pos);
521 tagstr_pos += strlen(tagstr_pos);
522 }
523
524 sldns_str2wire_dname_buf_origin(tagstr, dnamebuf, &dnamebuf_len,
525 ta->name, ta->namelen);
526 if(!(keytagdname = (uint8_t*)regional_alloc_init(qstate->region,
527 dnamebuf, dnamebuf_len))) {
528 log_err("could not generate key tag query: out of memory");
529 return 0;
530 }
531
532 log_nametypeclass(VERB_OPS, "generate keytag query", keytagdname,
533 LDNS_RR_TYPE_NULL, ta->dclass);
534 if(!generate_request(qstate, id, keytagdname, dnamebuf_len,
535 LDNS_RR_TYPE_NULL, ta->dclass, 0, &newq, 1)) {
536 verbose(VERB_ALGO, "failed to generate key tag signaling request");
537 return 0;
538 }
539
540 /* Not interested in subquery response. Restore the ext_state,
541 * that might be changed by generate_request() */
542 qstate->ext_state[id] = ext_state;
543
544 return 1;
545 }
546
547 /**
548 * Get keytag as uint16_t from string
549 *
550 * @param start: start of string containing keytag
551 * @param keytag: pointer where to store the extracted keytag
552 * @return: 1 if keytag was extracted, else 0.
553 */
554 static int
sentinel_get_keytag(char * start,uint16_t * keytag)555 sentinel_get_keytag(char* start, uint16_t* keytag) {
556 char* keytag_str;
557 char* e = NULL;
558 keytag_str = calloc(1, SENTINEL_KEYTAG_LEN + 1 /* null byte */);
559 if(!keytag_str)
560 return 0;
561 memmove(keytag_str, start, SENTINEL_KEYTAG_LEN);
562 keytag_str[SENTINEL_KEYTAG_LEN] = '\0';
563 *keytag = (uint16_t)strtol(keytag_str, &e, 10);
564 if(!e || *e != '\0') {
565 free(keytag_str);
566 return 0;
567 }
568 free(keytag_str);
569 return 1;
570 }
571
572 /**
573 * Prime trust anchor for use.
574 * Generate and dispatch a priming query for the given trust anchor.
575 * The trust anchor can be DNSKEY or DS and does not have to be signed.
576 *
577 * @param qstate: query state.
578 * @param vq: validator query state.
579 * @param id: module id.
580 * @param toprime: what to prime.
581 * @return false on a processing error.
582 */
583 static int
prime_trust_anchor(struct module_qstate * qstate,struct val_qstate * vq,int id,struct trust_anchor * toprime)584 prime_trust_anchor(struct module_qstate* qstate, struct val_qstate* vq,
585 int id, struct trust_anchor* toprime)
586 {
587 struct module_qstate* newq = NULL;
588 int ret = generate_request(qstate, id, toprime->name, toprime->namelen,
589 LDNS_RR_TYPE_DNSKEY, toprime->dclass, BIT_CD, &newq, 0);
590
591 if(newq && qstate->env->cfg->trust_anchor_signaling &&
592 !generate_keytag_query(qstate, id, toprime)) {
593 verbose(VERB_ALGO, "keytag signaling query failed");
594 return 0;
595 }
596
597 if(!ret) {
598 verbose(VERB_ALGO, "Could not prime trust anchor");
599 return 0;
600 }
601 /* ignore newq; validator does not need state created for that
602 * query, and its a 'normal' for iterator as well */
603 vq->wait_prime_ta = 1; /* to elicit PRIME_RESP_STATE processing
604 from the validator inform_super() routine */
605 /* store trust anchor name for later lookup when prime returns */
606 vq->trust_anchor_name = regional_alloc_init(qstate->region,
607 toprime->name, toprime->namelen);
608 vq->trust_anchor_len = toprime->namelen;
609 vq->trust_anchor_labs = toprime->namelabs;
610 if(!vq->trust_anchor_name) {
611 log_err("Could not prime trust anchor: out of memory");
612 return 0;
613 }
614 return 1;
615 }
616
617 /**
618 * Validate if the ANSWER and AUTHORITY sections contain valid rrsets.
619 * They must be validly signed with the given key.
620 * Tries to validate ADDITIONAL rrsets as well, but only to check them.
621 * Allows unsigned CNAME after a DNAME that expands the DNAME.
622 *
623 * Note that by the time this method is called, the process of finding the
624 * trusted DNSKEY rrset that signs this response must already have been
625 * completed.
626 *
627 * @param qstate: query state.
628 * @param vq: validator query state.
629 * @param env: module env for verify.
630 * @param ve: validator env for verify.
631 * @param chase_reply: answer to validate.
632 * @param key_entry: the key entry, which is trusted, and which matches
633 * the signer of the answer. The key entry isgood().
634 * @param suspend: returned true if the task takes too long and needs to
635 * suspend to continue the effort later.
636 * @return false if any of the rrsets in the an or ns sections of the message
637 * fail to verify. The message is then set to bogus.
638 */
639 static int
validate_msg_signatures(struct module_qstate * qstate,struct val_qstate * vq,struct module_env * env,struct val_env * ve,struct reply_info * chase_reply,struct key_entry_key * key_entry,int * suspend)640 validate_msg_signatures(struct module_qstate* qstate, struct val_qstate* vq,
641 struct module_env* env, struct val_env* ve,
642 struct reply_info* chase_reply, struct key_entry_key* key_entry,
643 int* suspend)
644 {
645 uint8_t* sname;
646 size_t i, slen;
647 struct ub_packed_rrset_key* s;
648 enum sec_status sec;
649 int num_verifies = 0, verified, have_state = 0;
650 char reasonbuf[256];
651 char* reason = NULL;
652 sldns_ede_code reason_bogus = LDNS_EDE_DNSSEC_BOGUS;
653 *suspend = 0;
654 if(vq->msg_signatures_state) {
655 /* Pick up the state, and reset it, may not be needed now. */
656 vq->msg_signatures_state = 0;
657 have_state = 1;
658 }
659
660 /* validate the ANSWER section */
661 for(i=0; i<chase_reply->an_numrrsets; i++) {
662 if(have_state && i <= vq->msg_signatures_index)
663 continue;
664 s = chase_reply->rrsets[i];
665 /* Skip the CNAME following a (validated) DNAME.
666 * Because of the normalization routines in the iterator,
667 * there will always be an unsigned CNAME following a DNAME
668 * (unless qtype=DNAME in the answer part). */
669 if(i>0 && ntohs(chase_reply->rrsets[i-1]->rk.type) ==
670 LDNS_RR_TYPE_DNAME &&
671 ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME &&
672 ((struct packed_rrset_data*)chase_reply->rrsets[i-1]->entry.data)->security == sec_status_secure &&
673 dname_strict_subdomain_c(s->rk.dname, chase_reply->rrsets[i-1]->rk.dname)
674 ) {
675 /* CNAME was synthesized by our own iterator */
676 /* since the DNAME verified, mark the CNAME as secure */
677 ((struct packed_rrset_data*)s->entry.data)->security =
678 sec_status_secure;
679 ((struct packed_rrset_data*)s->entry.data)->trust =
680 rrset_trust_validated;
681 continue;
682 }
683
684 /* Verify the answer rrset */
685 sec = val_verify_rrset_entry(env, ve, s, key_entry, &reason,
686 &reason_bogus, LDNS_SECTION_ANSWER, qstate, &verified,
687 reasonbuf, sizeof(reasonbuf));
688 /* If the (answer) rrset failed to validate, then this
689 * message is BAD. */
690 if(sec != sec_status_secure) {
691 log_nametypeclass(VERB_QUERY, "validator: response "
692 "has failed ANSWER rrset:", s->rk.dname,
693 ntohs(s->rk.type), ntohs(s->rk.rrset_class));
694 errinf_ede(qstate, reason, reason_bogus);
695 if(ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME)
696 errinf(qstate, "for CNAME");
697 else if(ntohs(s->rk.type) == LDNS_RR_TYPE_DNAME)
698 errinf(qstate, "for DNAME");
699 errinf_origin(qstate, qstate->reply_origin);
700 chase_reply->security = sec_status_bogus;
701 update_reason_bogus(chase_reply, reason_bogus);
702
703 return 0;
704 }
705
706 num_verifies += verified;
707 if(num_verifies > MAX_VALIDATE_AT_ONCE &&
708 i+1 < (env->cfg->val_clean_additional?
709 chase_reply->an_numrrsets+chase_reply->ns_numrrsets:
710 chase_reply->rrset_count)) {
711 /* If the number of RRSIGs exceeds the maximum in
712 * one go, suspend. Only suspend if there is a next
713 * rrset to verify, i+1<loopmax. Store where to
714 * continue later. */
715 *suspend = 1;
716 vq->msg_signatures_state = 1;
717 vq->msg_signatures_index = i;
718 verbose(VERB_ALGO, "msg signature validation "
719 "suspended");
720 return 0;
721 }
722 }
723
724 /* validate the AUTHORITY section */
725 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+
726 chase_reply->ns_numrrsets; i++) {
727 if(have_state && i <= vq->msg_signatures_index)
728 continue;
729 s = chase_reply->rrsets[i];
730 sec = val_verify_rrset_entry(env, ve, s, key_entry, &reason,
731 &reason_bogus, LDNS_SECTION_AUTHORITY, qstate,
732 &verified, reasonbuf, sizeof(reasonbuf));
733 /* If anything in the authority section fails to be secure,
734 * we have a bad message. */
735 if(sec != sec_status_secure) {
736 log_nametypeclass(VERB_QUERY, "validator: response "
737 "has failed AUTHORITY rrset:", s->rk.dname,
738 ntohs(s->rk.type), ntohs(s->rk.rrset_class));
739 errinf_ede(qstate, reason, reason_bogus);
740 errinf_origin(qstate, qstate->reply_origin);
741 errinf_rrset(qstate, s);
742 chase_reply->security = sec_status_bogus;
743 update_reason_bogus(chase_reply, reason_bogus);
744 return 0;
745 }
746 num_verifies += verified;
747 if(num_verifies > MAX_VALIDATE_AT_ONCE &&
748 i+1 < (env->cfg->val_clean_additional?
749 chase_reply->an_numrrsets+chase_reply->ns_numrrsets:
750 chase_reply->rrset_count)) {
751 *suspend = 1;
752 vq->msg_signatures_state = 1;
753 vq->msg_signatures_index = i;
754 verbose(VERB_ALGO, "msg signature validation "
755 "suspended");
756 return 0;
757 }
758 }
759
760 /* If set, the validator should clean the additional section of
761 * secure messages. */
762 if(!env->cfg->val_clean_additional)
763 return 1;
764 /* attempt to validate the ADDITIONAL section rrsets */
765 for(i=chase_reply->an_numrrsets+chase_reply->ns_numrrsets;
766 i<chase_reply->rrset_count; i++) {
767 if(have_state && i <= vq->msg_signatures_index)
768 continue;
769 s = chase_reply->rrsets[i];
770 /* only validate rrs that have signatures with the key */
771 /* leave others unchecked, those get removed later on too */
772 val_find_rrset_signer(s, &sname, &slen);
773
774 verified = 0;
775 if(sname && query_dname_compare(sname, key_entry->name)==0)
776 (void)val_verify_rrset_entry(env, ve, s, key_entry,
777 &reason, NULL, LDNS_SECTION_ADDITIONAL, qstate,
778 &verified, reasonbuf, sizeof(reasonbuf));
779 /* the additional section can fail to be secure,
780 * it is optional, check signature in case we need
781 * to clean the additional section later. */
782 num_verifies += verified;
783 if(num_verifies > MAX_VALIDATE_AT_ONCE &&
784 i+1 < chase_reply->rrset_count) {
785 *suspend = 1;
786 vq->msg_signatures_state = 1;
787 vq->msg_signatures_index = i;
788 verbose(VERB_ALGO, "msg signature validation "
789 "suspended");
790 return 0;
791 }
792 }
793
794 return 1;
795 }
796
797 void
validate_suspend_timer_cb(void * arg)798 validate_suspend_timer_cb(void* arg)
799 {
800 struct module_qstate* qstate = (struct module_qstate*)arg;
801 verbose(VERB_ALGO, "validate_suspend timer, continue");
802 mesh_run(qstate->env->mesh, qstate->mesh_info, module_event_pass,
803 NULL);
804 }
805
806 /** Setup timer to continue validation of msg signatures later */
807 static int
validate_suspend_setup_timer(struct module_qstate * qstate,struct val_qstate * vq,int id,enum val_state resume_state)808 validate_suspend_setup_timer(struct module_qstate* qstate,
809 struct val_qstate* vq, int id, enum val_state resume_state)
810 {
811 struct timeval tv;
812 int usec, slack, base;
813 if(vq->suspend_count >= MAX_VALIDATION_SUSPENDS) {
814 verbose(VERB_ALGO, "validate_suspend timer: "
815 "reached MAX_VALIDATION_SUSPENDS (%d); error out",
816 MAX_VALIDATION_SUSPENDS);
817 errinf(qstate, "max validation suspends reached, "
818 "too many RRSIG validations");
819 return 0;
820 }
821 verbose(VERB_ALGO, "validate_suspend timer, set for suspend");
822 vq->state = resume_state;
823 qstate->ext_state[id] = module_wait_reply;
824 if(!vq->suspend_timer) {
825 vq->suspend_timer = comm_timer_create(
826 qstate->env->worker_base,
827 validate_suspend_timer_cb, qstate);
828 if(!vq->suspend_timer) {
829 log_err("validate_suspend_setup_timer: "
830 "out of memory for comm_timer_create");
831 return 0;
832 }
833 }
834 /* The timer is activated later, after other events in the event
835 * loop have been processed. The query state can also be deleted,
836 * when the list is full and query states are dropped. */
837 /* Extend wait time if there are a lot of queries or if this one
838 * is taking long, to keep around cpu time for ordinary queries. */
839 usec = 50000; /* 50 msec */
840 slack = 0;
841 if(qstate->env->mesh->all.count >= qstate->env->mesh->max_reply_states)
842 slack += 3;
843 else if(qstate->env->mesh->all.count >= qstate->env->mesh->max_reply_states/2)
844 slack += 2;
845 else if(qstate->env->mesh->all.count >= qstate->env->mesh->max_reply_states/4)
846 slack += 1;
847 if(vq->suspend_count > 3)
848 slack += 3;
849 else if(vq->suspend_count > 0)
850 slack += vq->suspend_count;
851 if(slack != 0 && slack <= 12 /* No numeric overflow. */) {
852 usec = usec << slack;
853 }
854 /* Spread such timeouts within 90%-100% of the original timer. */
855 base = usec * 9/10;
856 usec = base + ub_random_max(qstate->env->rnd, usec-base);
857 tv.tv_usec = (usec % 1000000);
858 tv.tv_sec = (usec / 1000000);
859 vq->suspend_count ++;
860 comm_timer_set(vq->suspend_timer, &tv);
861 return 1;
862 }
863
864 /**
865 * Detect wrong truncated response (say from BIND 9.6.1 that is forwarding
866 * and saw the NS record without signatures from a referral).
867 * The positive response has a mangled authority section.
868 * Remove that authority section and the additional section.
869 * @param rep: reply
870 * @return true if a wrongly truncated response.
871 */
872 static int
detect_wrongly_truncated(struct reply_info * rep)873 detect_wrongly_truncated(struct reply_info* rep)
874 {
875 size_t i;
876 /* only NS in authority, and it is bogus */
877 if(rep->ns_numrrsets != 1 || rep->an_numrrsets == 0)
878 return 0;
879 if(ntohs(rep->rrsets[ rep->an_numrrsets ]->rk.type) != LDNS_RR_TYPE_NS)
880 return 0;
881 if(((struct packed_rrset_data*)rep->rrsets[ rep->an_numrrsets ]
882 ->entry.data)->security == sec_status_secure)
883 return 0;
884 /* answer section is present and secure */
885 for(i=0; i<rep->an_numrrsets; i++) {
886 if(((struct packed_rrset_data*)rep->rrsets[ i ]
887 ->entry.data)->security != sec_status_secure)
888 return 0;
889 }
890 verbose(VERB_ALGO, "truncating to minimal response");
891 return 1;
892 }
893
894 /**
895 * For messages that are not referrals, if the chase reply contains an
896 * unsigned NS record in the authority section it could have been
897 * inserted by a (BIND) forwarder that thinks the zone is insecure, and
898 * that has an NS record without signatures in cache. Remove the NS
899 * record since the reply does not hinge on that record (in the authority
900 * section), but do not remove it if it removes the last record from the
901 * answer+authority sections.
902 * @param chase_reply: the chased reply, we have a key for this contents,
903 * so we should have signatures for these rrsets and not having
904 * signatures means it will be bogus.
905 * @param orig_reply: original reply, remove NS from there as well because
906 * we cannot mark the NS record as DNSSEC valid because it is not
907 * validated by signatures.
908 */
909 static void
remove_spurious_authority(struct reply_info * chase_reply,struct reply_info * orig_reply)910 remove_spurious_authority(struct reply_info* chase_reply,
911 struct reply_info* orig_reply)
912 {
913 size_t i, found = 0;
914 int remove = 0;
915 /* if no answer and only 1 auth RRset, do not remove that one */
916 if(chase_reply->an_numrrsets == 0 && chase_reply->ns_numrrsets == 1)
917 return;
918 /* search authority section for unsigned NS records */
919 for(i = chase_reply->an_numrrsets;
920 i < chase_reply->an_numrrsets+chase_reply->ns_numrrsets; i++) {
921 struct packed_rrset_data* d = (struct packed_rrset_data*)
922 chase_reply->rrsets[i]->entry.data;
923 if(ntohs(chase_reply->rrsets[i]->rk.type) == LDNS_RR_TYPE_NS
924 && d->rrsig_count == 0) {
925 found = i;
926 remove = 1;
927 break;
928 }
929 }
930 /* see if we found the entry */
931 if(!remove) return;
932 log_rrset_key(VERB_ALGO, "Removing spurious unsigned NS record "
933 "(likely inserted by forwarder)", chase_reply->rrsets[found]);
934
935 /* find rrset in orig_reply */
936 for(i = orig_reply->an_numrrsets;
937 i < orig_reply->an_numrrsets+orig_reply->ns_numrrsets; i++) {
938 if(ntohs(orig_reply->rrsets[i]->rk.type) == LDNS_RR_TYPE_NS
939 && query_dname_compare(orig_reply->rrsets[i]->rk.dname,
940 chase_reply->rrsets[found]->rk.dname) == 0) {
941 /* remove from orig_msg */
942 val_reply_remove_auth(orig_reply, i);
943 break;
944 }
945 }
946 /* remove rrset from chase_reply */
947 val_reply_remove_auth(chase_reply, found);
948 }
949
950 /**
951 * Given a "positive" response -- a response that contains an answer to the
952 * question, and no CNAME chain, validate this response.
953 *
954 * The answer and authority RRsets must already be verified as secure.
955 *
956 * @param env: module env for verify.
957 * @param ve: validator env for verify.
958 * @param qchase: query that was made.
959 * @param chase_reply: answer to that query to validate.
960 * @param kkey: the key entry, which is trusted, and which matches
961 * the signer of the answer. The key entry isgood().
962 * @param qstate: query state for the region.
963 * @param vq: validator state for the nsec3 cache table.
964 * @param nsec3_calculations: current nsec3 hash calculations.
965 * @param suspend: returned true if the task takes too long and needs to
966 * suspend to continue the effort later.
967 */
968 static void
validate_positive_response(struct module_env * env,struct val_env * ve,struct query_info * qchase,struct reply_info * chase_reply,struct key_entry_key * kkey,struct module_qstate * qstate,struct val_qstate * vq,int * nsec3_calculations,int * suspend)969 validate_positive_response(struct module_env* env, struct val_env* ve,
970 struct query_info* qchase, struct reply_info* chase_reply,
971 struct key_entry_key* kkey, struct module_qstate* qstate,
972 struct val_qstate* vq, int* nsec3_calculations, int* suspend)
973 {
974 uint8_t* wc = NULL;
975 size_t wl;
976 int wc_cached = 0;
977 int wc_NSEC_ok = 0;
978 int nsec3s_seen = 0;
979 size_t i;
980 struct ub_packed_rrset_key* s;
981 *suspend = 0;
982
983 /* validate the ANSWER section - this will be the answer itself */
984 for(i=0; i<chase_reply->an_numrrsets; i++) {
985 s = chase_reply->rrsets[i];
986
987 /* Check to see if the rrset is the result of a wildcard
988 * expansion. If so, an additional check will need to be
989 * made in the authority section. */
990 if(!val_rrset_wildcard(s, &wc, &wl)) {
991 log_nametypeclass(VERB_QUERY, "Positive response has "
992 "inconsistent wildcard sigs:", s->rk.dname,
993 ntohs(s->rk.type), ntohs(s->rk.rrset_class));
994 chase_reply->security = sec_status_bogus;
995 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
996 return;
997 }
998 if(wc && !wc_cached && env->cfg->aggressive_nsec) {
999 rrset_cache_update_wildcard(env->rrset_cache, s, wc, wl,
1000 env->alloc, *env->now);
1001 wc_cached = 1;
1002 }
1003
1004 }
1005
1006 /* validate the AUTHORITY section as well - this will generally be
1007 * the NS rrset (which could be missing, no problem) */
1008 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+
1009 chase_reply->ns_numrrsets; i++) {
1010 s = chase_reply->rrsets[i];
1011
1012 /* If this is a positive wildcard response, and we have a
1013 * (just verified) NSEC record, try to use it to 1) prove
1014 * that qname doesn't exist and 2) that the correct wildcard
1015 * was used. */
1016 if(wc != NULL && ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) {
1017 if(val_nsec_proves_positive_wildcard(s, qchase, wc)) {
1018 wc_NSEC_ok = 1;
1019 }
1020 /* if not, continue looking for proof */
1021 }
1022
1023 /* Otherwise, if this is a positive wildcard response and
1024 * we have NSEC3 records */
1025 if(wc != NULL && ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) {
1026 nsec3s_seen = 1;
1027 }
1028 }
1029
1030 /* If this was a positive wildcard response that we haven't already
1031 * proven, and we have NSEC3 records, try to prove it using the NSEC3
1032 * records. */
1033 if(wc != NULL && !wc_NSEC_ok && nsec3s_seen &&
1034 nsec3_cache_table_init(&vq->nsec3_cache_table, qstate->region)) {
1035 enum sec_status sec = nsec3_prove_wildcard(env, ve,
1036 chase_reply->rrsets+chase_reply->an_numrrsets,
1037 chase_reply->ns_numrrsets, qchase, kkey, wc,
1038 &vq->nsec3_cache_table, nsec3_calculations);
1039 if(sec == sec_status_insecure) {
1040 verbose(VERB_ALGO, "Positive wildcard response is "
1041 "insecure");
1042 chase_reply->security = sec_status_insecure;
1043 return;
1044 } else if(sec == sec_status_secure) {
1045 wc_NSEC_ok = 1;
1046 } else if(sec == sec_status_unchecked) {
1047 *suspend = 1;
1048 return;
1049 }
1050 }
1051
1052 /* If after all this, we still haven't proven the positive wildcard
1053 * response, fail. */
1054 if(wc != NULL && !wc_NSEC_ok) {
1055 verbose(VERB_QUERY, "positive response was wildcard "
1056 "expansion and did not prove original data "
1057 "did not exist");
1058 chase_reply->security = sec_status_bogus;
1059 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1060 return;
1061 }
1062
1063 verbose(VERB_ALGO, "Successfully validated positive response");
1064 chase_reply->security = sec_status_secure;
1065 }
1066
1067 /**
1068 * Validate a NOERROR/NODATA signed response -- a response that has a
1069 * NOERROR Rcode but no ANSWER section RRsets. This consists of making
1070 * certain that the authority section NSEC/NSEC3s proves that the qname
1071 * does exist and the qtype doesn't.
1072 *
1073 * The answer and authority RRsets must already be verified as secure.
1074 *
1075 * @param env: module env for verify.
1076 * @param ve: validator env for verify.
1077 * @param qchase: query that was made.
1078 * @param chase_reply: answer to that query to validate.
1079 * @param kkey: the key entry, which is trusted, and which matches
1080 * the signer of the answer. The key entry isgood().
1081 * @param qstate: query state for the region.
1082 * @param vq: validator state for the nsec3 cache table.
1083 * @param nsec3_calculations: current nsec3 hash calculations.
1084 * @param suspend: returned true if the task takes too long and needs to
1085 * suspend to continue the effort later.
1086 */
1087 static void
validate_nodata_response(struct module_env * env,struct val_env * ve,struct query_info * qchase,struct reply_info * chase_reply,struct key_entry_key * kkey,struct module_qstate * qstate,struct val_qstate * vq,int * nsec3_calculations,int * suspend)1088 validate_nodata_response(struct module_env* env, struct val_env* ve,
1089 struct query_info* qchase, struct reply_info* chase_reply,
1090 struct key_entry_key* kkey, struct module_qstate* qstate,
1091 struct val_qstate* vq, int* nsec3_calculations, int* suspend)
1092 {
1093 /* Since we are here, there must be nothing in the ANSWER section to
1094 * validate. */
1095 /* (Note: CNAME/DNAME responses will not directly get here --
1096 * instead, they are chased down into individual CNAME validations,
1097 * and at the end of the cname chain a POSITIVE, or CNAME_NOANSWER
1098 * validation.) */
1099
1100 /* validate the AUTHORITY section */
1101 int has_valid_nsec = 0; /* If true, then the NODATA has been proven.*/
1102 uint8_t* ce = NULL; /* for wildcard nodata responses. This is the
1103 proven closest encloser. */
1104 uint8_t* wc = NULL; /* for wildcard nodata responses. wildcard nsec */
1105 int nsec3s_seen = 0; /* nsec3s seen */
1106 struct ub_packed_rrset_key* s;
1107 size_t i;
1108 *suspend = 0;
1109
1110 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+
1111 chase_reply->ns_numrrsets; i++) {
1112 s = chase_reply->rrsets[i];
1113 /* If we encounter an NSEC record, try to use it to prove
1114 * NODATA.
1115 * This needs to handle the ENT NODATA case. */
1116 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) {
1117 if(nsec_proves_nodata(s, qchase, &wc)) {
1118 has_valid_nsec = 1;
1119 /* sets wc-encloser if wildcard applicable */
1120 }
1121 if(val_nsec_proves_name_error(s, qchase->qname)) {
1122 ce = nsec_closest_encloser(qchase->qname, s);
1123 }
1124 if(val_nsec_proves_insecuredelegation(s, qchase)) {
1125 verbose(VERB_ALGO, "delegation is insecure");
1126 chase_reply->security = sec_status_insecure;
1127 return;
1128 }
1129 } else if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) {
1130 nsec3s_seen = 1;
1131 }
1132 }
1133
1134 /* check to see if we have a wildcard NODATA proof. */
1135
1136 /* The wildcard NODATA is 1 NSEC proving that qname does not exist
1137 * (and also proving what the closest encloser is), and 1 NSEC
1138 * showing the matching wildcard, which must be *.closest_encloser. */
1139 if(wc && !ce)
1140 has_valid_nsec = 0;
1141 else if(wc && ce) {
1142 if(query_dname_compare(wc, ce) != 0) {
1143 has_valid_nsec = 0;
1144 }
1145 }
1146
1147 if(!has_valid_nsec && nsec3s_seen &&
1148 nsec3_cache_table_init(&vq->nsec3_cache_table, qstate->region)) {
1149 enum sec_status sec = nsec3_prove_nodata(env, ve,
1150 chase_reply->rrsets+chase_reply->an_numrrsets,
1151 chase_reply->ns_numrrsets, qchase, kkey,
1152 &vq->nsec3_cache_table, nsec3_calculations);
1153 if(sec == sec_status_insecure) {
1154 verbose(VERB_ALGO, "NODATA response is insecure");
1155 chase_reply->security = sec_status_insecure;
1156 return;
1157 } else if(sec == sec_status_secure) {
1158 has_valid_nsec = 1;
1159 } else if(sec == sec_status_unchecked) {
1160 /* check is incomplete; suspend */
1161 *suspend = 1;
1162 return;
1163 }
1164 }
1165
1166 if(!has_valid_nsec) {
1167 verbose(VERB_QUERY, "NODATA response failed to prove NODATA "
1168 "status with NSEC/NSEC3");
1169 if(verbosity >= VERB_ALGO)
1170 log_dns_msg("Failed NODATA", qchase, chase_reply);
1171 chase_reply->security = sec_status_bogus;
1172 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1173 return;
1174 }
1175
1176 verbose(VERB_ALGO, "successfully validated NODATA response.");
1177 chase_reply->security = sec_status_secure;
1178 }
1179
1180 /**
1181 * Validate a NAMEERROR signed response -- a response that has a NXDOMAIN
1182 * Rcode.
1183 * This consists of making certain that the authority section NSEC proves
1184 * that the qname doesn't exist and the covering wildcard also doesn't exist..
1185 *
1186 * The answer and authority RRsets must have already been verified as secure.
1187 *
1188 * @param env: module env for verify.
1189 * @param ve: validator env for verify.
1190 * @param qchase: query that was made.
1191 * @param chase_reply: answer to that query to validate.
1192 * @param kkey: the key entry, which is trusted, and which matches
1193 * the signer of the answer. The key entry isgood().
1194 * @param rcode: adjusted RCODE, in case of RCODE/proof mismatch leniency.
1195 * @param qstate: query state for the region.
1196 * @param vq: validator state for the nsec3 cache table.
1197 * @param nsec3_calculations: current nsec3 hash calculations.
1198 * @param suspend: returned true if the task takes too long and needs to
1199 * suspend to continue the effort later.
1200 */
1201 static void
validate_nameerror_response(struct module_env * env,struct val_env * ve,struct query_info * qchase,struct reply_info * chase_reply,struct key_entry_key * kkey,int * rcode,struct module_qstate * qstate,struct val_qstate * vq,int * nsec3_calculations,int * suspend)1202 validate_nameerror_response(struct module_env* env, struct val_env* ve,
1203 struct query_info* qchase, struct reply_info* chase_reply,
1204 struct key_entry_key* kkey, int* rcode,
1205 struct module_qstate* qstate, struct val_qstate* vq,
1206 int* nsec3_calculations, int* suspend)
1207 {
1208 int has_valid_nsec = 0;
1209 int has_valid_wnsec = 0;
1210 int nsec3s_seen = 0;
1211 struct ub_packed_rrset_key* s;
1212 size_t i;
1213 uint8_t* ce;
1214 int ce_labs = 0;
1215 int prev_ce_labs = 0;
1216 *suspend = 0;
1217
1218 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+
1219 chase_reply->ns_numrrsets; i++) {
1220 s = chase_reply->rrsets[i];
1221 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) {
1222 if(val_nsec_proves_name_error(s, qchase->qname))
1223 has_valid_nsec = 1;
1224 ce = nsec_closest_encloser(qchase->qname, s);
1225 ce_labs = dname_count_labels(ce);
1226 /* Use longest closest encloser to prove wildcard. */
1227 if(ce_labs > prev_ce_labs ||
1228 (ce_labs == prev_ce_labs &&
1229 has_valid_wnsec == 0)) {
1230 if(val_nsec_proves_no_wc(s, qchase->qname,
1231 qchase->qname_len))
1232 has_valid_wnsec = 1;
1233 else
1234 has_valid_wnsec = 0;
1235 }
1236 prev_ce_labs = ce_labs;
1237 if(val_nsec_proves_insecuredelegation(s, qchase)) {
1238 verbose(VERB_ALGO, "delegation is insecure");
1239 chase_reply->security = sec_status_insecure;
1240 return;
1241 }
1242 } else if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3)
1243 nsec3s_seen = 1;
1244 }
1245
1246 if((!has_valid_nsec || !has_valid_wnsec) && nsec3s_seen &&
1247 nsec3_cache_table_init(&vq->nsec3_cache_table, qstate->region)) {
1248 /* use NSEC3 proof, both answer and auth rrsets, in case
1249 * NSEC3s end up in the answer (due to qtype=NSEC3 or so) */
1250 chase_reply->security = nsec3_prove_nameerror(env, ve,
1251 chase_reply->rrsets, chase_reply->an_numrrsets+
1252 chase_reply->ns_numrrsets, qchase, kkey,
1253 &vq->nsec3_cache_table, nsec3_calculations);
1254 if(chase_reply->security == sec_status_unchecked) {
1255 *suspend = 1;
1256 return;
1257 } else if(chase_reply->security != sec_status_secure) {
1258 verbose(VERB_QUERY, "NameError response failed nsec, "
1259 "nsec3 proof was %s", sec_status_to_string(
1260 chase_reply->security));
1261 return;
1262 }
1263 has_valid_nsec = 1;
1264 has_valid_wnsec = 1;
1265 }
1266
1267 /* If the message fails to prove either condition, it is bogus. */
1268 if(!has_valid_nsec) {
1269 validate_nodata_response(env, ve, qchase, chase_reply, kkey,
1270 qstate, vq, nsec3_calculations, suspend);
1271 if(*suspend) return;
1272 verbose(VERB_QUERY, "NameError response has failed to prove: "
1273 "qname does not exist");
1274 /* Be lenient with RCODE in NSEC NameError responses */
1275 if(chase_reply->security == sec_status_secure) {
1276 *rcode = LDNS_RCODE_NOERROR;
1277 } else {
1278 chase_reply->security = sec_status_bogus;
1279 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1280 }
1281 return;
1282 }
1283
1284 if(!has_valid_wnsec) {
1285 validate_nodata_response(env, ve, qchase, chase_reply, kkey,
1286 qstate, vq, nsec3_calculations, suspend);
1287 if(*suspend) return;
1288 verbose(VERB_QUERY, "NameError response has failed to prove: "
1289 "covering wildcard does not exist");
1290 /* Be lenient with RCODE in NSEC NameError responses */
1291 if (chase_reply->security == sec_status_secure) {
1292 *rcode = LDNS_RCODE_NOERROR;
1293 } else {
1294 chase_reply->security = sec_status_bogus;
1295 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1296 }
1297 return;
1298 }
1299
1300 /* Otherwise, we consider the message secure. */
1301 verbose(VERB_ALGO, "successfully validated NAME ERROR response.");
1302 chase_reply->security = sec_status_secure;
1303 }
1304
1305 /**
1306 * Given a referral response, validate rrsets and take least trusted rrset
1307 * as the current validation status.
1308 *
1309 * Note that by the time this method is called, the process of finding the
1310 * trusted DNSKEY rrset that signs this response must already have been
1311 * completed.
1312 *
1313 * @param chase_reply: answer to validate.
1314 */
1315 static void
validate_referral_response(struct reply_info * chase_reply)1316 validate_referral_response(struct reply_info* chase_reply)
1317 {
1318 size_t i;
1319 enum sec_status s;
1320 /* message security equals lowest rrset security */
1321 chase_reply->security = sec_status_secure;
1322 for(i=0; i<chase_reply->rrset_count; i++) {
1323 s = ((struct packed_rrset_data*)chase_reply->rrsets[i]
1324 ->entry.data)->security;
1325 if(s < chase_reply->security)
1326 chase_reply->security = s;
1327 }
1328 verbose(VERB_ALGO, "validated part of referral response as %s",
1329 sec_status_to_string(chase_reply->security));
1330 }
1331
1332 /**
1333 * Given an "ANY" response -- a response that contains an answer to a
1334 * qtype==ANY question, with answers. This does no checking that all
1335 * types are present.
1336 *
1337 * NOTE: it may be possible to get parent-side delegation point records
1338 * here, which won't all be signed. Right now, this routine relies on the
1339 * upstream iterative resolver to not return these responses -- instead
1340 * treating them as referrals.
1341 *
1342 * NOTE: RFC 4035 is silent on this issue, so this may change upon
1343 * clarification. Clarification draft -05 says to not check all types are
1344 * present.
1345 *
1346 * Note that by the time this method is called, the process of finding the
1347 * trusted DNSKEY rrset that signs this response must already have been
1348 * completed.
1349 *
1350 * @param env: module env for verify.
1351 * @param ve: validator env for verify.
1352 * @param qchase: query that was made.
1353 * @param chase_reply: answer to that query to validate.
1354 * @param kkey: the key entry, which is trusted, and which matches
1355 * the signer of the answer. The key entry isgood().
1356 * @param qstate: query state for the region.
1357 * @param vq: validator state for the nsec3 cache table.
1358 * @param nsec3_calculations: current nsec3 hash calculations.
1359 * @param suspend: returned true if the task takes too long and needs to
1360 * suspend to continue the effort later.
1361 */
1362 static void
validate_any_response(struct module_env * env,struct val_env * ve,struct query_info * qchase,struct reply_info * chase_reply,struct key_entry_key * kkey,struct module_qstate * qstate,struct val_qstate * vq,int * nsec3_calculations,int * suspend)1363 validate_any_response(struct module_env* env, struct val_env* ve,
1364 struct query_info* qchase, struct reply_info* chase_reply,
1365 struct key_entry_key* kkey, struct module_qstate* qstate,
1366 struct val_qstate* vq, int* nsec3_calculations, int* suspend)
1367 {
1368 /* all answer and auth rrsets already verified */
1369 /* but check if a wildcard response is given, then check NSEC/NSEC3
1370 * for qname denial to see if wildcard is applicable */
1371 uint8_t* wc = NULL;
1372 size_t wl;
1373 int wc_NSEC_ok = 0;
1374 int nsec3s_seen = 0;
1375 size_t i;
1376 struct ub_packed_rrset_key* s;
1377 *suspend = 0;
1378
1379 if(qchase->qtype != LDNS_RR_TYPE_ANY) {
1380 log_err("internal error: ANY validation called for non-ANY");
1381 chase_reply->security = sec_status_bogus;
1382 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1383 return;
1384 }
1385
1386 /* validate the ANSWER section - this will be the answer itself */
1387 for(i=0; i<chase_reply->an_numrrsets; i++) {
1388 s = chase_reply->rrsets[i];
1389
1390 /* Check to see if the rrset is the result of a wildcard
1391 * expansion. If so, an additional check will need to be
1392 * made in the authority section. */
1393 if(!val_rrset_wildcard(s, &wc, &wl)) {
1394 log_nametypeclass(VERB_QUERY, "Positive ANY response"
1395 " has inconsistent wildcard sigs:",
1396 s->rk.dname, ntohs(s->rk.type),
1397 ntohs(s->rk.rrset_class));
1398 chase_reply->security = sec_status_bogus;
1399 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1400 return;
1401 }
1402 }
1403
1404 /* if it was a wildcard, check for NSEC/NSEC3s in both answer
1405 * and authority sections (NSEC may be moved to the ANSWER section) */
1406 if(wc != NULL)
1407 for(i=0; i<chase_reply->an_numrrsets+chase_reply->ns_numrrsets;
1408 i++) {
1409 s = chase_reply->rrsets[i];
1410
1411 /* If this is a positive wildcard response, and we have a
1412 * (just verified) NSEC record, try to use it to 1) prove
1413 * that qname doesn't exist and 2) that the correct wildcard
1414 * was used. */
1415 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) {
1416 if(val_nsec_proves_positive_wildcard(s, qchase, wc)) {
1417 wc_NSEC_ok = 1;
1418 }
1419 /* if not, continue looking for proof */
1420 }
1421
1422 /* Otherwise, if this is a positive wildcard response and
1423 * we have NSEC3 records */
1424 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) {
1425 nsec3s_seen = 1;
1426 }
1427 }
1428
1429 /* If this was a positive wildcard response that we haven't already
1430 * proven, and we have NSEC3 records, try to prove it using the NSEC3
1431 * records. */
1432 if(wc != NULL && !wc_NSEC_ok && nsec3s_seen &&
1433 nsec3_cache_table_init(&vq->nsec3_cache_table, qstate->region)) {
1434 /* look both in answer and auth section for NSEC3s */
1435 enum sec_status sec = nsec3_prove_wildcard(env, ve,
1436 chase_reply->rrsets,
1437 chase_reply->an_numrrsets+chase_reply->ns_numrrsets,
1438 qchase, kkey, wc, &vq->nsec3_cache_table,
1439 nsec3_calculations);
1440 if(sec == sec_status_insecure) {
1441 verbose(VERB_ALGO, "Positive ANY wildcard response is "
1442 "insecure");
1443 chase_reply->security = sec_status_insecure;
1444 return;
1445 } else if(sec == sec_status_secure) {
1446 wc_NSEC_ok = 1;
1447 } else if(sec == sec_status_unchecked) {
1448 *suspend = 1;
1449 return;
1450 }
1451 }
1452
1453 /* If after all this, we still haven't proven the positive wildcard
1454 * response, fail. */
1455 if(wc != NULL && !wc_NSEC_ok) {
1456 verbose(VERB_QUERY, "positive ANY response was wildcard "
1457 "expansion and did not prove original data "
1458 "did not exist");
1459 chase_reply->security = sec_status_bogus;
1460 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1461 return;
1462 }
1463
1464 verbose(VERB_ALGO, "Successfully validated positive ANY response");
1465 chase_reply->security = sec_status_secure;
1466 }
1467
1468 /**
1469 * Validate CNAME response, or DNAME+CNAME.
1470 * This is just like a positive proof, except that this is about a
1471 * DNAME+CNAME. Possible wildcard proof.
1472 * Difference with positive proof is that this routine refuses
1473 * wildcarded DNAMEs.
1474 *
1475 * The answer and authority rrsets must already be verified as secure.
1476 *
1477 * @param env: module env for verify.
1478 * @param ve: validator env for verify.
1479 * @param qchase: query that was made.
1480 * @param chase_reply: answer to that query to validate.
1481 * @param kkey: the key entry, which is trusted, and which matches
1482 * the signer of the answer. The key entry isgood().
1483 * @param qstate: query state for the region.
1484 * @param vq: validator state for the nsec3 cache table.
1485 * @param nsec3_calculations: current nsec3 hash calculations.
1486 * @param suspend: returned true if the task takes too long and needs to
1487 * suspend to continue the effort later.
1488 */
1489 static void
validate_cname_response(struct module_env * env,struct val_env * ve,struct query_info * qchase,struct reply_info * chase_reply,struct key_entry_key * kkey,struct module_qstate * qstate,struct val_qstate * vq,int * nsec3_calculations,int * suspend)1490 validate_cname_response(struct module_env* env, struct val_env* ve,
1491 struct query_info* qchase, struct reply_info* chase_reply,
1492 struct key_entry_key* kkey, struct module_qstate* qstate,
1493 struct val_qstate* vq, int* nsec3_calculations, int* suspend)
1494 {
1495 uint8_t* wc = NULL;
1496 size_t wl;
1497 int wc_NSEC_ok = 0;
1498 int nsec3s_seen = 0;
1499 size_t i;
1500 struct ub_packed_rrset_key* s;
1501 *suspend = 0;
1502
1503 /* validate the ANSWER section - this will be the CNAME (+DNAME) */
1504 for(i=0; i<chase_reply->an_numrrsets; i++) {
1505 s = chase_reply->rrsets[i];
1506
1507 /* Check to see if the rrset is the result of a wildcard
1508 * expansion. If so, an additional check will need to be
1509 * made in the authority section. */
1510 if(!val_rrset_wildcard(s, &wc, &wl)) {
1511 log_nametypeclass(VERB_QUERY, "Cname response has "
1512 "inconsistent wildcard sigs:", s->rk.dname,
1513 ntohs(s->rk.type), ntohs(s->rk.rrset_class));
1514 chase_reply->security = sec_status_bogus;
1515 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1516 return;
1517 }
1518
1519 /* Refuse wildcarded DNAMEs rfc 4597.
1520 * Do not follow a wildcarded DNAME because
1521 * its synthesized CNAME expansion is underdefined */
1522 if(qchase->qtype != LDNS_RR_TYPE_DNAME &&
1523 ntohs(s->rk.type) == LDNS_RR_TYPE_DNAME && wc) {
1524 log_nametypeclass(VERB_QUERY, "cannot validate a "
1525 "wildcarded DNAME:", s->rk.dname,
1526 ntohs(s->rk.type), ntohs(s->rk.rrset_class));
1527 chase_reply->security = sec_status_bogus;
1528 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1529 return;
1530 }
1531
1532 /* If we have found a CNAME, stop looking for one.
1533 * The iterator has placed the CNAME chain in correct
1534 * order. */
1535 if (ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME) {
1536 break;
1537 }
1538 }
1539
1540 /* AUTHORITY section */
1541 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+
1542 chase_reply->ns_numrrsets; i++) {
1543 s = chase_reply->rrsets[i];
1544
1545 /* If this is a positive wildcard response, and we have a
1546 * (just verified) NSEC record, try to use it to 1) prove
1547 * that qname doesn't exist and 2) that the correct wildcard
1548 * was used. */
1549 if(wc != NULL && ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) {
1550 if(val_nsec_proves_positive_wildcard(s, qchase, wc)) {
1551 wc_NSEC_ok = 1;
1552 }
1553 /* if not, continue looking for proof */
1554 }
1555
1556 /* Otherwise, if this is a positive wildcard response and
1557 * we have NSEC3 records */
1558 if(wc != NULL && ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) {
1559 nsec3s_seen = 1;
1560 }
1561 }
1562
1563 /* If this was a positive wildcard response that we haven't already
1564 * proven, and we have NSEC3 records, try to prove it using the NSEC3
1565 * records. */
1566 if(wc != NULL && !wc_NSEC_ok && nsec3s_seen &&
1567 nsec3_cache_table_init(&vq->nsec3_cache_table, qstate->region)) {
1568 enum sec_status sec = nsec3_prove_wildcard(env, ve,
1569 chase_reply->rrsets+chase_reply->an_numrrsets,
1570 chase_reply->ns_numrrsets, qchase, kkey, wc,
1571 &vq->nsec3_cache_table, nsec3_calculations);
1572 if(sec == sec_status_insecure) {
1573 verbose(VERB_ALGO, "wildcard CNAME response is "
1574 "insecure");
1575 chase_reply->security = sec_status_insecure;
1576 return;
1577 } else if(sec == sec_status_secure) {
1578 wc_NSEC_ok = 1;
1579 } else if(sec == sec_status_unchecked) {
1580 *suspend = 1;
1581 return;
1582 }
1583 }
1584
1585 /* If after all this, we still haven't proven the positive wildcard
1586 * response, fail. */
1587 if(wc != NULL && !wc_NSEC_ok) {
1588 verbose(VERB_QUERY, "CNAME response was wildcard "
1589 "expansion and did not prove original data "
1590 "did not exist");
1591 chase_reply->security = sec_status_bogus;
1592 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1593 return;
1594 }
1595
1596 verbose(VERB_ALGO, "Successfully validated CNAME response");
1597 chase_reply->security = sec_status_secure;
1598 }
1599
1600 /**
1601 * Validate CNAME NOANSWER response, no more data after a CNAME chain.
1602 * This can be a NODATA or a NAME ERROR case, but not both at the same time.
1603 * We don't know because the rcode has been set to NOERROR by the CNAME.
1604 *
1605 * The answer and authority rrsets must already be verified as secure.
1606 *
1607 * @param env: module env for verify.
1608 * @param ve: validator env for verify.
1609 * @param qchase: query that was made.
1610 * @param chase_reply: answer to that query to validate.
1611 * @param kkey: the key entry, which is trusted, and which matches
1612 * the signer of the answer. The key entry isgood().
1613 * @param qstate: query state for the region.
1614 * @param vq: validator state for the nsec3 cache table.
1615 * @param nsec3_calculations: current nsec3 hash calculations.
1616 * @param suspend: returned true if the task takes too long and needs to
1617 * suspend to continue the effort later.
1618 */
1619 static void
validate_cname_noanswer_response(struct module_env * env,struct val_env * ve,struct query_info * qchase,struct reply_info * chase_reply,struct key_entry_key * kkey,struct module_qstate * qstate,struct val_qstate * vq,int * nsec3_calculations,int * suspend)1620 validate_cname_noanswer_response(struct module_env* env, struct val_env* ve,
1621 struct query_info* qchase, struct reply_info* chase_reply,
1622 struct key_entry_key* kkey, struct module_qstate* qstate,
1623 struct val_qstate* vq, int* nsec3_calculations, int* suspend)
1624 {
1625 int nodata_valid_nsec = 0; /* If true, then NODATA has been proven.*/
1626 uint8_t* ce = NULL; /* for wildcard nodata responses. This is the
1627 proven closest encloser. */
1628 uint8_t* wc = NULL; /* for wildcard nodata responses. wildcard nsec */
1629 int nxdomain_valid_nsec = 0; /* if true, nameerror has been proven */
1630 int nxdomain_valid_wnsec = 0;
1631 int nsec3s_seen = 0; /* nsec3s seen */
1632 struct ub_packed_rrset_key* s;
1633 size_t i;
1634 uint8_t* nsec_ce; /* Used to find the NSEC with the longest ce */
1635 int ce_labs = 0;
1636 int prev_ce_labs = 0;
1637 *suspend = 0;
1638
1639 /* the AUTHORITY section */
1640 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+
1641 chase_reply->ns_numrrsets; i++) {
1642 s = chase_reply->rrsets[i];
1643
1644 /* If we encounter an NSEC record, try to use it to prove
1645 * NODATA. This needs to handle the ENT NODATA case.
1646 * Also try to prove NAMEERROR, and absence of a wildcard */
1647 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) {
1648 if(nsec_proves_nodata(s, qchase, &wc)) {
1649 nodata_valid_nsec = 1;
1650 /* set wc encloser if wildcard applicable */
1651 }
1652 if(val_nsec_proves_name_error(s, qchase->qname)) {
1653 ce = nsec_closest_encloser(qchase->qname, s);
1654 nxdomain_valid_nsec = 1;
1655 }
1656 nsec_ce = nsec_closest_encloser(qchase->qname, s);
1657 ce_labs = dname_count_labels(nsec_ce);
1658 /* Use longest closest encloser to prove wildcard. */
1659 if(ce_labs > prev_ce_labs ||
1660 (ce_labs == prev_ce_labs &&
1661 nxdomain_valid_wnsec == 0)) {
1662 if(val_nsec_proves_no_wc(s, qchase->qname,
1663 qchase->qname_len))
1664 nxdomain_valid_wnsec = 1;
1665 else
1666 nxdomain_valid_wnsec = 0;
1667 }
1668 prev_ce_labs = ce_labs;
1669 if(val_nsec_proves_insecuredelegation(s, qchase)) {
1670 verbose(VERB_ALGO, "delegation is insecure");
1671 chase_reply->security = sec_status_insecure;
1672 return;
1673 }
1674 } else if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) {
1675 nsec3s_seen = 1;
1676 }
1677 }
1678
1679 /* check to see if we have a wildcard NODATA proof. */
1680
1681 /* The wildcard NODATA is 1 NSEC proving that qname does not exists
1682 * (and also proving what the closest encloser is), and 1 NSEC
1683 * showing the matching wildcard, which must be *.closest_encloser. */
1684 if(wc && !ce)
1685 nodata_valid_nsec = 0;
1686 else if(wc && ce) {
1687 if(query_dname_compare(wc, ce) != 0) {
1688 nodata_valid_nsec = 0;
1689 }
1690 }
1691 if(nxdomain_valid_nsec && !nxdomain_valid_wnsec) {
1692 /* name error is missing wildcard denial proof */
1693 nxdomain_valid_nsec = 0;
1694 }
1695
1696 if(nodata_valid_nsec && nxdomain_valid_nsec) {
1697 verbose(VERB_QUERY, "CNAMEchain to noanswer proves that name "
1698 "exists and not exists, bogus");
1699 chase_reply->security = sec_status_bogus;
1700 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1701 return;
1702 }
1703 if(!nodata_valid_nsec && !nxdomain_valid_nsec && nsec3s_seen &&
1704 nsec3_cache_table_init(&vq->nsec3_cache_table, qstate->region)) {
1705 int nodata;
1706 enum sec_status sec = nsec3_prove_nxornodata(env, ve,
1707 chase_reply->rrsets+chase_reply->an_numrrsets,
1708 chase_reply->ns_numrrsets, qchase, kkey, &nodata,
1709 &vq->nsec3_cache_table, nsec3_calculations);
1710 if(sec == sec_status_insecure) {
1711 verbose(VERB_ALGO, "CNAMEchain to noanswer response "
1712 "is insecure");
1713 chase_reply->security = sec_status_insecure;
1714 return;
1715 } else if(sec == sec_status_secure) {
1716 if(nodata)
1717 nodata_valid_nsec = 1;
1718 else nxdomain_valid_nsec = 1;
1719 } else if(sec == sec_status_unchecked) {
1720 *suspend = 1;
1721 return;
1722 }
1723 }
1724
1725 if(!nodata_valid_nsec && !nxdomain_valid_nsec) {
1726 verbose(VERB_QUERY, "CNAMEchain to noanswer response failed "
1727 "to prove status with NSEC/NSEC3");
1728 if(verbosity >= VERB_ALGO)
1729 log_dns_msg("Failed CNAMEnoanswer", qchase, chase_reply);
1730 chase_reply->security = sec_status_bogus;
1731 update_reason_bogus(chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1732 return;
1733 }
1734
1735 if(nodata_valid_nsec)
1736 verbose(VERB_ALGO, "successfully validated CNAME chain to a "
1737 "NODATA response.");
1738 else verbose(VERB_ALGO, "successfully validated CNAME chain to a "
1739 "NAMEERROR response.");
1740 chase_reply->security = sec_status_secure;
1741 }
1742
1743 /**
1744 * Process init state for validator.
1745 * Process the INIT state. First tier responses start in the INIT state.
1746 * This is where they are vetted for validation suitability, and the initial
1747 * key search is done.
1748 *
1749 * Currently, events the come through this routine will be either promoted
1750 * to FINISHED/CNAME_RESP (no validation needed), FINDKEY (next step to
1751 * validation), or will be (temporarily) retired and a new priming request
1752 * event will be generated.
1753 *
1754 * @param qstate: query state.
1755 * @param vq: validator query state.
1756 * @param ve: validator shared global environment.
1757 * @param id: module id.
1758 * @return true if the event should be processed further on return, false if
1759 * not.
1760 */
1761 static int
processInit(struct module_qstate * qstate,struct val_qstate * vq,struct val_env * ve,int id)1762 processInit(struct module_qstate* qstate, struct val_qstate* vq,
1763 struct val_env* ve, int id)
1764 {
1765 uint8_t* lookup_name;
1766 size_t lookup_len;
1767 struct trust_anchor* anchor;
1768 enum val_classification subtype = val_classify_response(
1769 qstate->query_flags, &qstate->qinfo, &vq->qchase,
1770 vq->orig_msg->rep, vq->rrset_skip);
1771 if(vq->restart_count > ve->max_restart) {
1772 verbose(VERB_ALGO, "restart count exceeded");
1773 return val_error(qstate, id);
1774 }
1775
1776 /* correctly initialize reason_bogus */
1777 update_reason_bogus(vq->chase_reply, LDNS_EDE_DNSSEC_BOGUS);
1778
1779 verbose(VERB_ALGO, "validator classification %s",
1780 val_classification_to_string(subtype));
1781 if(subtype == VAL_CLASS_REFERRAL &&
1782 vq->rrset_skip < vq->orig_msg->rep->rrset_count) {
1783 /* referral uses the rrset name as qchase, to find keys for
1784 * that rrset */
1785 vq->qchase.qname = vq->orig_msg->rep->
1786 rrsets[vq->rrset_skip]->rk.dname;
1787 vq->qchase.qname_len = vq->orig_msg->rep->
1788 rrsets[vq->rrset_skip]->rk.dname_len;
1789 vq->qchase.qtype = ntohs(vq->orig_msg->rep->
1790 rrsets[vq->rrset_skip]->rk.type);
1791 vq->qchase.qclass = ntohs(vq->orig_msg->rep->
1792 rrsets[vq->rrset_skip]->rk.rrset_class);
1793 }
1794 lookup_name = vq->qchase.qname;
1795 lookup_len = vq->qchase.qname_len;
1796 /* for type DS look at the parent side for keys/trustanchor */
1797 /* also for NSEC not at apex */
1798 if(vq->qchase.qtype == LDNS_RR_TYPE_DS ||
1799 (vq->qchase.qtype == LDNS_RR_TYPE_NSEC &&
1800 vq->orig_msg->rep->rrset_count > vq->rrset_skip &&
1801 ntohs(vq->orig_msg->rep->rrsets[vq->rrset_skip]->rk.type) ==
1802 LDNS_RR_TYPE_NSEC &&
1803 !(vq->orig_msg->rep->rrsets[vq->rrset_skip]->
1804 rk.flags&PACKED_RRSET_NSEC_AT_APEX))) {
1805 dname_remove_label(&lookup_name, &lookup_len);
1806 }
1807
1808 val_mark_indeterminate(vq->chase_reply, qstate->env->anchors,
1809 qstate->env->rrset_cache, qstate->env);
1810 vq->key_entry = NULL;
1811 vq->empty_DS_name = NULL;
1812 vq->ds_rrset = 0;
1813 anchor = anchors_lookup(qstate->env->anchors,
1814 lookup_name, lookup_len, vq->qchase.qclass);
1815
1816 /* Determine the signer/lookup name */
1817 val_find_signer(subtype, &vq->qchase, vq->orig_msg->rep,
1818 vq->rrset_skip, &vq->signer_name, &vq->signer_len);
1819 if(vq->signer_name != NULL &&
1820 !dname_subdomain_c(lookup_name, vq->signer_name)) {
1821 log_nametypeclass(VERB_ALGO, "this signer name is not a parent "
1822 "of lookupname, omitted", vq->signer_name, 0, 0);
1823 vq->signer_name = NULL;
1824 }
1825 if(vq->signer_name == NULL) {
1826 log_nametypeclass(VERB_ALGO, "no signer, using", lookup_name,
1827 0, 0);
1828 } else {
1829 lookup_name = vq->signer_name;
1830 lookup_len = vq->signer_len;
1831 log_nametypeclass(VERB_ALGO, "signer is", lookup_name, 0, 0);
1832 }
1833
1834 /* for NXDOMAIN it could be signed by a parent of the trust anchor */
1835 if(subtype == VAL_CLASS_NAMEERROR && vq->signer_name &&
1836 anchor && dname_strict_subdomain_c(anchor->name, lookup_name)){
1837 lock_basic_unlock(&anchor->lock);
1838 anchor = anchors_lookup(qstate->env->anchors,
1839 lookup_name, lookup_len, vq->qchase.qclass);
1840 if(!anchor) { /* unsigned parent denies anchor*/
1841 verbose(VERB_QUERY, "unsigned parent zone denies"
1842 " trust anchor, indeterminate");
1843 vq->chase_reply->security = sec_status_indeterminate;
1844 update_reason_bogus(vq->chase_reply, LDNS_EDE_DNSSEC_INDETERMINATE);
1845 vq->state = VAL_FINISHED_STATE;
1846 return 1;
1847 }
1848 verbose(VERB_ALGO, "trust anchor NXDOMAIN by signed parent");
1849 } else if(subtype == VAL_CLASS_POSITIVE &&
1850 qstate->qinfo.qtype == LDNS_RR_TYPE_DNSKEY &&
1851 query_dname_compare(lookup_name, qstate->qinfo.qname) == 0) {
1852 /* is a DNSKEY so lookup a bit higher since we want to
1853 * get it from a parent or from trustanchor */
1854 dname_remove_label(&lookup_name, &lookup_len);
1855 }
1856
1857 if(vq->rrset_skip > 0 || subtype == VAL_CLASS_CNAME ||
1858 subtype == VAL_CLASS_REFERRAL) {
1859 /* extract this part of orig_msg into chase_reply for
1860 * the eventual VALIDATE stage */
1861 val_fill_reply(vq->chase_reply, vq->orig_msg->rep,
1862 vq->rrset_skip, lookup_name, lookup_len,
1863 vq->signer_name);
1864 if(verbosity >= VERB_ALGO)
1865 log_dns_msg("chased extract", &vq->qchase,
1866 vq->chase_reply);
1867 }
1868
1869 vq->key_entry = key_cache_obtain(ve->kcache, lookup_name, lookup_len,
1870 vq->qchase.qclass, qstate->region, *qstate->env->now);
1871
1872 /* there is no key and no trust anchor */
1873 if(vq->key_entry == NULL && anchor == NULL) {
1874 /*response isn't under a trust anchor, so we cannot validate.*/
1875 vq->chase_reply->security = sec_status_indeterminate;
1876 update_reason_bogus(vq->chase_reply, LDNS_EDE_DNSSEC_INDETERMINATE);
1877 /* go to finished state to cache this result */
1878 vq->state = VAL_FINISHED_STATE;
1879 return 1;
1880 }
1881 /* if not key, or if keyentry is *above* the trustanchor, i.e.
1882 * the keyentry is based on another (higher) trustanchor */
1883 else if(vq->key_entry == NULL || (anchor &&
1884 dname_strict_subdomain_c(anchor->name, vq->key_entry->name))) {
1885 /* trust anchor is an 'unsigned' trust anchor */
1886 if(anchor && anchor->numDS == 0 && anchor->numDNSKEY == 0) {
1887 vq->chase_reply->security = sec_status_insecure;
1888 val_mark_insecure(vq->chase_reply, anchor->name,
1889 qstate->env->rrset_cache, qstate->env);
1890 lock_basic_unlock(&anchor->lock);
1891 /* go to finished state to cache this result */
1892 vq->state = VAL_FINISHED_STATE;
1893 return 1;
1894 }
1895 /* fire off a trust anchor priming query. */
1896 verbose(VERB_DETAIL, "prime trust anchor");
1897 if(!prime_trust_anchor(qstate, vq, id, anchor)) {
1898 lock_basic_unlock(&anchor->lock);
1899 return val_error(qstate, id);
1900 }
1901 lock_basic_unlock(&anchor->lock);
1902 /* and otherwise, don't continue processing this event.
1903 * (it will be reactivated when the priming query returns). */
1904 vq->state = VAL_FINDKEY_STATE;
1905 return 0;
1906 }
1907 if(anchor) {
1908 lock_basic_unlock(&anchor->lock);
1909 }
1910
1911 if(key_entry_isnull(vq->key_entry)) {
1912 /* response is under a null key, so we cannot validate
1913 * However, we do set the status to INSECURE, since it is
1914 * essentially proven insecure. */
1915 vq->chase_reply->security = sec_status_insecure;
1916 val_mark_insecure(vq->chase_reply, vq->key_entry->name,
1917 qstate->env->rrset_cache, qstate->env);
1918 /* go to finished state to cache this result */
1919 vq->state = VAL_FINISHED_STATE;
1920 return 1;
1921 } else if(key_entry_isbad(vq->key_entry)) {
1922 /* Bad keys should have the relevant EDE code and text */
1923 sldns_ede_code ede = key_entry_get_reason_bogus(vq->key_entry);
1924 /* key is bad, chain is bad, reply is bogus */
1925 errinf_dname(qstate, "key for validation", vq->key_entry->name);
1926 errinf_ede(qstate, "is marked as invalid", ede);
1927 errinf(qstate, "because of a previous");
1928 errinf(qstate, key_entry_get_reason(vq->key_entry));
1929
1930 /* no retries, stop bothering the authority until timeout */
1931 vq->restart_count = ve->max_restart;
1932 vq->chase_reply->security = sec_status_bogus;
1933 update_reason_bogus(vq->chase_reply, ede);
1934 vq->state = VAL_FINISHED_STATE;
1935 return 1;
1936 }
1937
1938 /* otherwise, we have our "closest" cached key -- continue
1939 * processing in the next state. */
1940 vq->state = VAL_FINDKEY_STATE;
1941 return 1;
1942 }
1943
1944 /**
1945 * Process the FINDKEY state. Generally this just calculates the next name
1946 * to query and either issues a DS or a DNSKEY query. It will check to see
1947 * if the correct key has already been reached, in which case it will
1948 * advance the event to the next state.
1949 *
1950 * @param qstate: query state.
1951 * @param vq: validator query state.
1952 * @param id: module id.
1953 * @return true if the event should be processed further on return, false if
1954 * not.
1955 */
1956 static int
processFindKey(struct module_qstate * qstate,struct val_qstate * vq,int id)1957 processFindKey(struct module_qstate* qstate, struct val_qstate* vq, int id)
1958 {
1959 uint8_t* target_key_name, *current_key_name;
1960 size_t target_key_len;
1961 int strip_lab;
1962 struct module_qstate* newq = NULL;
1963
1964 log_query_info(VERB_ALGO, "validator: FindKey", &vq->qchase);
1965 /* We know that state.key_entry is not 0 or bad key -- if it were,
1966 * then previous processing should have directed this event to
1967 * a different state.
1968 * It could be an isnull key, which signals the DNSKEY failed
1969 * with retry and has to be looked up again. */
1970 log_assert(vq->key_entry && !key_entry_isbad(vq->key_entry));
1971 if(key_entry_isnull(vq->key_entry)) {
1972 if(!generate_request(qstate, id, vq->ds_rrset->rk.dname,
1973 vq->ds_rrset->rk.dname_len, LDNS_RR_TYPE_DNSKEY,
1974 vq->qchase.qclass, BIT_CD, &newq, 0)) {
1975 verbose(VERB_ALGO, "error generating DNSKEY request");
1976 return val_error(qstate, id);
1977 }
1978 return 0;
1979 }
1980
1981 target_key_name = vq->signer_name;
1982 target_key_len = vq->signer_len;
1983 if(!target_key_name) {
1984 target_key_name = vq->qchase.qname;
1985 target_key_len = vq->qchase.qname_len;
1986 }
1987
1988 current_key_name = vq->key_entry->name;
1989
1990 /* If our current key entry matches our target, then we are done. */
1991 if(query_dname_compare(target_key_name, current_key_name) == 0) {
1992 vq->state = VAL_VALIDATE_STATE;
1993 return 1;
1994 }
1995
1996 if(vq->empty_DS_name) {
1997 /* if the last empty nonterminal/emptyDS name we detected is
1998 * below the current key, use that name to make progress
1999 * along the chain of trust */
2000 if(query_dname_compare(target_key_name,
2001 vq->empty_DS_name) == 0) {
2002 /* do not query for empty_DS_name again */
2003 verbose(VERB_ALGO, "Cannot retrieve DS for signature");
2004 errinf_ede(qstate, "no signatures", LDNS_EDE_RRSIGS_MISSING);
2005 errinf_origin(qstate, qstate->reply_origin);
2006 vq->chase_reply->security = sec_status_bogus;
2007 update_reason_bogus(vq->chase_reply, LDNS_EDE_RRSIGS_MISSING);
2008 vq->state = VAL_FINISHED_STATE;
2009 return 1;
2010 }
2011 current_key_name = vq->empty_DS_name;
2012 }
2013
2014 log_nametypeclass(VERB_ALGO, "current keyname", current_key_name,
2015 LDNS_RR_TYPE_DNSKEY, LDNS_RR_CLASS_IN);
2016 log_nametypeclass(VERB_ALGO, "target keyname", target_key_name,
2017 LDNS_RR_TYPE_DNSKEY, LDNS_RR_CLASS_IN);
2018 /* assert we are walking down the DNS tree */
2019 if(!dname_subdomain_c(target_key_name, current_key_name)) {
2020 verbose(VERB_ALGO, "bad signer name");
2021 vq->chase_reply->security = sec_status_bogus;
2022 vq->state = VAL_FINISHED_STATE;
2023 return 1;
2024 }
2025 /* so this value is >= -1 */
2026 strip_lab = dname_count_labels(target_key_name) -
2027 dname_count_labels(current_key_name) - 1;
2028 log_assert(strip_lab >= -1);
2029 verbose(VERB_ALGO, "striplab %d", strip_lab);
2030 if(strip_lab > 0) {
2031 dname_remove_labels(&target_key_name, &target_key_len,
2032 strip_lab);
2033 }
2034 log_nametypeclass(VERB_ALGO, "next keyname", target_key_name,
2035 LDNS_RR_TYPE_DNSKEY, LDNS_RR_CLASS_IN);
2036
2037 /* The next step is either to query for the next DS, or to query
2038 * for the next DNSKEY. */
2039 if(vq->ds_rrset)
2040 log_nametypeclass(VERB_ALGO, "DS RRset", vq->ds_rrset->rk.dname, LDNS_RR_TYPE_DS, LDNS_RR_CLASS_IN);
2041 else verbose(VERB_ALGO, "No DS RRset");
2042
2043 if(vq->ds_rrset && query_dname_compare(vq->ds_rrset->rk.dname,
2044 vq->key_entry->name) != 0) {
2045 if(!generate_request(qstate, id, vq->ds_rrset->rk.dname,
2046 vq->ds_rrset->rk.dname_len, LDNS_RR_TYPE_DNSKEY,
2047 vq->qchase.qclass, BIT_CD, &newq, 0)) {
2048 verbose(VERB_ALGO, "error generating DNSKEY request");
2049 return val_error(qstate, id);
2050 }
2051 return 0;
2052 }
2053
2054 if(!vq->ds_rrset || query_dname_compare(vq->ds_rrset->rk.dname,
2055 target_key_name) != 0) {
2056 /* check if there is a cache entry : pick up an NSEC if
2057 * there is no DS, check if that NSEC has DS-bit unset, and
2058 * thus can disprove the secure delegation we seek.
2059 * We can then use that NSEC even in the absence of a SOA
2060 * record that would be required by the iterator to supply
2061 * a completely protocol-correct response.
2062 * Uses negative cache for NSEC3 lookup of DS responses. */
2063 /* only if cache not blacklisted, of course */
2064 struct dns_msg* msg;
2065 int suspend;
2066 if(vq->sub_ds_msg) {
2067 /* We have a suspended DS reply from a sub-query;
2068 * process it. */
2069 verbose(VERB_ALGO, "Process suspended sub DS response");
2070 msg = vq->sub_ds_msg;
2071 process_ds_response(qstate, vq, id, LDNS_RCODE_NOERROR,
2072 msg, &msg->qinfo, NULL, &suspend, NULL);
2073 if(suspend) {
2074 /* we'll come back here later to continue */
2075 if(!validate_suspend_setup_timer(qstate, vq,
2076 id, VAL_FINDKEY_STATE))
2077 return val_error(qstate, id);
2078 return 0;
2079 }
2080 vq->sub_ds_msg = NULL;
2081 return 1; /* continue processing ds-response results */
2082 } else if(!qstate->blacklist && !vq->chain_blacklist &&
2083 (msg=val_find_DS(qstate->env, target_key_name,
2084 target_key_len, vq->qchase.qclass, qstate->region,
2085 vq->key_entry->name)) ) {
2086 verbose(VERB_ALGO, "Process cached DS response");
2087 process_ds_response(qstate, vq, id, LDNS_RCODE_NOERROR,
2088 msg, &msg->qinfo, NULL, &suspend, NULL);
2089 if(suspend) {
2090 /* we'll come back here later to continue */
2091 if(!validate_suspend_setup_timer(qstate, vq,
2092 id, VAL_FINDKEY_STATE))
2093 return val_error(qstate, id);
2094 return 0;
2095 }
2096 return 1; /* continue processing ds-response results */
2097 }
2098 if(!generate_request(qstate, id, target_key_name,
2099 target_key_len, LDNS_RR_TYPE_DS, vq->qchase.qclass,
2100 BIT_CD, &newq, 0)) {
2101 verbose(VERB_ALGO, "error generating DS request");
2102 return val_error(qstate, id);
2103 }
2104 return 0;
2105 }
2106
2107 /* Otherwise, it is time to query for the DNSKEY */
2108 if(!generate_request(qstate, id, vq->ds_rrset->rk.dname,
2109 vq->ds_rrset->rk.dname_len, LDNS_RR_TYPE_DNSKEY,
2110 vq->qchase.qclass, BIT_CD, &newq, 0)) {
2111 verbose(VERB_ALGO, "error generating DNSKEY request");
2112 return val_error(qstate, id);
2113 }
2114
2115 return 0;
2116 }
2117
2118 /**
2119 * Process the VALIDATE stage, the init and findkey stages are finished,
2120 * and the right keys are available to validate the response.
2121 * Or, there are no keys available, in order to invalidate the response.
2122 *
2123 * After validation, the status is recorded in the message and rrsets,
2124 * and finished state is started.
2125 *
2126 * @param qstate: query state.
2127 * @param vq: validator query state.
2128 * @param ve: validator shared global environment.
2129 * @param id: module id.
2130 * @return true if the event should be processed further on return, false if
2131 * not.
2132 */
2133 static int
processValidate(struct module_qstate * qstate,struct val_qstate * vq,struct val_env * ve,int id)2134 processValidate(struct module_qstate* qstate, struct val_qstate* vq,
2135 struct val_env* ve, int id)
2136 {
2137 enum val_classification subtype;
2138 int rcode, suspend, nsec3_calculations = 0;
2139
2140 if(!vq->key_entry) {
2141 verbose(VERB_ALGO, "validate: no key entry, failed");
2142 return val_error(qstate, id);
2143 }
2144
2145 /* This is the default next state. */
2146 vq->state = VAL_FINISHED_STATE;
2147
2148 /* Unsigned responses must be underneath a "null" key entry.*/
2149 if(key_entry_isnull(vq->key_entry)) {
2150 verbose(VERB_DETAIL, "Verified that %sresponse is INSECURE",
2151 vq->signer_name?"":"unsigned ");
2152 vq->chase_reply->security = sec_status_insecure;
2153 val_mark_insecure(vq->chase_reply, vq->key_entry->name,
2154 qstate->env->rrset_cache, qstate->env);
2155 key_cache_insert(ve->kcache, vq->key_entry,
2156 qstate->env->cfg->val_log_level >= 2);
2157 return 1;
2158 }
2159
2160 if(key_entry_isbad(vq->key_entry)) {
2161 log_nametypeclass(VERB_DETAIL, "Could not establish a chain "
2162 "of trust to keys for", vq->key_entry->name,
2163 LDNS_RR_TYPE_DNSKEY, vq->key_entry->key_class);
2164 vq->chase_reply->security = sec_status_bogus;
2165 update_reason_bogus(vq->chase_reply,
2166 key_entry_get_reason_bogus(vq->key_entry));
2167 errinf_ede(qstate, "while building chain of trust",
2168 key_entry_get_reason_bogus(vq->key_entry));
2169 if(vq->restart_count >= ve->max_restart)
2170 key_cache_insert(ve->kcache, vq->key_entry,
2171 qstate->env->cfg->val_log_level >= 2);
2172 return 1;
2173 }
2174
2175 /* signerName being null is the indicator that this response was
2176 * unsigned */
2177 if(vq->signer_name == NULL) {
2178 log_query_info(VERB_ALGO, "processValidate: state has no "
2179 "signer name", &vq->qchase);
2180 verbose(VERB_DETAIL, "Could not establish validation of "
2181 "INSECURE status of unsigned response.");
2182 errinf_ede(qstate, "no signatures", LDNS_EDE_RRSIGS_MISSING);
2183 errinf_origin(qstate, qstate->reply_origin);
2184 vq->chase_reply->security = sec_status_bogus;
2185 update_reason_bogus(vq->chase_reply, LDNS_EDE_RRSIGS_MISSING);
2186 return 1;
2187 }
2188 subtype = val_classify_response(qstate->query_flags, &qstate->qinfo,
2189 &vq->qchase, vq->orig_msg->rep, vq->rrset_skip);
2190 if(subtype != VAL_CLASS_REFERRAL)
2191 remove_spurious_authority(vq->chase_reply, vq->orig_msg->rep);
2192
2193 /* check signatures in the message;
2194 * answer and authority must be valid, additional is only checked. */
2195 if(!validate_msg_signatures(qstate, vq, qstate->env, ve,
2196 vq->chase_reply, vq->key_entry, &suspend)) {
2197 if(suspend) {
2198 if(!validate_suspend_setup_timer(qstate, vq,
2199 id, VAL_VALIDATE_STATE))
2200 return val_error(qstate, id);
2201 return 0;
2202 }
2203 /* workaround bad recursor out there that truncates (even
2204 * with EDNS4k) to 512 by removing RRSIG from auth section
2205 * for positive replies*/
2206 if((subtype == VAL_CLASS_POSITIVE || subtype == VAL_CLASS_ANY
2207 || subtype == VAL_CLASS_CNAME) &&
2208 detect_wrongly_truncated(vq->orig_msg->rep)) {
2209 /* truncate the message some more */
2210 vq->orig_msg->rep->ns_numrrsets = 0;
2211 vq->orig_msg->rep->ar_numrrsets = 0;
2212 vq->orig_msg->rep->rrset_count =
2213 vq->orig_msg->rep->an_numrrsets;
2214 vq->chase_reply->ns_numrrsets = 0;
2215 vq->chase_reply->ar_numrrsets = 0;
2216 vq->chase_reply->rrset_count =
2217 vq->chase_reply->an_numrrsets;
2218 qstate->errinf = NULL;
2219 }
2220 else {
2221 verbose(VERB_DETAIL, "Validate: message contains "
2222 "bad rrsets");
2223 return 1;
2224 }
2225 }
2226
2227 switch(subtype) {
2228 case VAL_CLASS_POSITIVE:
2229 verbose(VERB_ALGO, "Validating a positive response");
2230 validate_positive_response(qstate->env, ve,
2231 &vq->qchase, vq->chase_reply, vq->key_entry,
2232 qstate, vq, &nsec3_calculations, &suspend);
2233 if(suspend) {
2234 if(!validate_suspend_setup_timer(qstate,
2235 vq, id, VAL_VALIDATE_STATE))
2236 return val_error(qstate, id);
2237 return 0;
2238 }
2239 verbose(VERB_DETAIL, "validate(positive): %s",
2240 sec_status_to_string(
2241 vq->chase_reply->security));
2242 break;
2243
2244 case VAL_CLASS_NODATA:
2245 verbose(VERB_ALGO, "Validating a nodata response");
2246 validate_nodata_response(qstate->env, ve,
2247 &vq->qchase, vq->chase_reply, vq->key_entry,
2248 qstate, vq, &nsec3_calculations, &suspend);
2249 if(suspend) {
2250 if(!validate_suspend_setup_timer(qstate,
2251 vq, id, VAL_VALIDATE_STATE))
2252 return val_error(qstate, id);
2253 return 0;
2254 }
2255 verbose(VERB_DETAIL, "validate(nodata): %s",
2256 sec_status_to_string(
2257 vq->chase_reply->security));
2258 break;
2259
2260 case VAL_CLASS_NAMEERROR:
2261 rcode = (int)FLAGS_GET_RCODE(vq->orig_msg->rep->flags);
2262 verbose(VERB_ALGO, "Validating a nxdomain response");
2263 validate_nameerror_response(qstate->env, ve,
2264 &vq->qchase, vq->chase_reply, vq->key_entry, &rcode,
2265 qstate, vq, &nsec3_calculations, &suspend);
2266 if(suspend) {
2267 if(!validate_suspend_setup_timer(qstate,
2268 vq, id, VAL_VALIDATE_STATE))
2269 return val_error(qstate, id);
2270 return 0;
2271 }
2272 verbose(VERB_DETAIL, "validate(nxdomain): %s",
2273 sec_status_to_string(
2274 vq->chase_reply->security));
2275 FLAGS_SET_RCODE(vq->orig_msg->rep->flags, rcode);
2276 FLAGS_SET_RCODE(vq->chase_reply->flags, rcode);
2277 break;
2278
2279 case VAL_CLASS_CNAME:
2280 verbose(VERB_ALGO, "Validating a cname response");
2281 validate_cname_response(qstate->env, ve,
2282 &vq->qchase, vq->chase_reply, vq->key_entry,
2283 qstate, vq, &nsec3_calculations, &suspend);
2284 if(suspend) {
2285 if(!validate_suspend_setup_timer(qstate,
2286 vq, id, VAL_VALIDATE_STATE))
2287 return val_error(qstate, id);
2288 return 0;
2289 }
2290 verbose(VERB_DETAIL, "validate(cname): %s",
2291 sec_status_to_string(
2292 vq->chase_reply->security));
2293 break;
2294
2295 case VAL_CLASS_CNAMENOANSWER:
2296 verbose(VERB_ALGO, "Validating a cname noanswer "
2297 "response");
2298 validate_cname_noanswer_response(qstate->env, ve,
2299 &vq->qchase, vq->chase_reply, vq->key_entry,
2300 qstate, vq, &nsec3_calculations, &suspend);
2301 if(suspend) {
2302 if(!validate_suspend_setup_timer(qstate,
2303 vq, id, VAL_VALIDATE_STATE))
2304 return val_error(qstate, id);
2305 return 0;
2306 }
2307 verbose(VERB_DETAIL, "validate(cname_noanswer): %s",
2308 sec_status_to_string(
2309 vq->chase_reply->security));
2310 break;
2311
2312 case VAL_CLASS_REFERRAL:
2313 verbose(VERB_ALGO, "Validating a referral response");
2314 validate_referral_response(vq->chase_reply);
2315 verbose(VERB_DETAIL, "validate(referral): %s",
2316 sec_status_to_string(
2317 vq->chase_reply->security));
2318 break;
2319
2320 case VAL_CLASS_ANY:
2321 verbose(VERB_ALGO, "Validating a positive ANY "
2322 "response");
2323 validate_any_response(qstate->env, ve, &vq->qchase,
2324 vq->chase_reply, vq->key_entry, qstate, vq,
2325 &nsec3_calculations, &suspend);
2326 if(suspend) {
2327 if(!validate_suspend_setup_timer(qstate,
2328 vq, id, VAL_VALIDATE_STATE))
2329 return val_error(qstate, id);
2330 return 0;
2331 }
2332 verbose(VERB_DETAIL, "validate(positive_any): %s",
2333 sec_status_to_string(
2334 vq->chase_reply->security));
2335 break;
2336
2337 default:
2338 log_err("validate: unhandled response subtype: %d",
2339 subtype);
2340 }
2341 if(vq->chase_reply->security == sec_status_bogus) {
2342 if(subtype == VAL_CLASS_POSITIVE)
2343 errinf(qstate, "wildcard");
2344 else errinf(qstate, val_classification_to_string(subtype));
2345 errinf(qstate, "proof failed");
2346 errinf_origin(qstate, qstate->reply_origin);
2347 }
2348
2349 return 1;
2350 }
2351
2352 /**
2353 * The Finished state. The validation status (good or bad) has been determined.
2354 *
2355 * @param qstate: query state.
2356 * @param vq: validator query state.
2357 * @param ve: validator shared global environment.
2358 * @param id: module id.
2359 * @return true if the event should be processed further on return, false if
2360 * not.
2361 */
2362 static int
processFinished(struct module_qstate * qstate,struct val_qstate * vq,struct val_env * ve,int id)2363 processFinished(struct module_qstate* qstate, struct val_qstate* vq,
2364 struct val_env* ve, int id)
2365 {
2366 enum val_classification subtype = val_classify_response(
2367 qstate->query_flags, &qstate->qinfo, &vq->qchase,
2368 vq->orig_msg->rep, vq->rrset_skip);
2369
2370 /* store overall validation result in orig_msg */
2371 if(vq->rrset_skip == 0) {
2372 vq->orig_msg->rep->security = vq->chase_reply->security;
2373 update_reason_bogus(vq->orig_msg->rep, vq->chase_reply->reason_bogus);
2374 } else if(subtype != VAL_CLASS_REFERRAL ||
2375 vq->rrset_skip < vq->orig_msg->rep->an_numrrsets +
2376 vq->orig_msg->rep->ns_numrrsets) {
2377 /* ignore sec status of additional section if a referral
2378 * type message skips there and
2379 * use the lowest security status as end result. */
2380 if(vq->chase_reply->security < vq->orig_msg->rep->security) {
2381 vq->orig_msg->rep->security =
2382 vq->chase_reply->security;
2383 update_reason_bogus(vq->orig_msg->rep, vq->chase_reply->reason_bogus);
2384 }
2385 }
2386
2387 if(subtype == VAL_CLASS_REFERRAL) {
2388 /* for a referral, move to next unchecked rrset and check it*/
2389 vq->rrset_skip = val_next_unchecked(vq->orig_msg->rep,
2390 vq->rrset_skip);
2391 if(vq->rrset_skip < vq->orig_msg->rep->rrset_count) {
2392 /* and restart for this rrset */
2393 verbose(VERB_ALGO, "validator: go to next rrset");
2394 vq->chase_reply->security = sec_status_unchecked;
2395 vq->state = VAL_INIT_STATE;
2396 return 1;
2397 }
2398 /* referral chase is done */
2399 }
2400 if(vq->chase_reply->security != sec_status_bogus &&
2401 subtype == VAL_CLASS_CNAME) {
2402 /* chase the CNAME; process next part of the message */
2403 if(!val_chase_cname(&vq->qchase, vq->orig_msg->rep,
2404 &vq->rrset_skip)) {
2405 verbose(VERB_ALGO, "validator: failed to chase CNAME");
2406 vq->orig_msg->rep->security = sec_status_bogus;
2407 update_reason_bogus(vq->orig_msg->rep, LDNS_EDE_DNSSEC_BOGUS);
2408 } else {
2409 /* restart process for new qchase at rrset_skip */
2410 log_query_info(VERB_ALGO, "validator: chased to",
2411 &vq->qchase);
2412 vq->chase_reply->security = sec_status_unchecked;
2413 vq->state = VAL_INIT_STATE;
2414 return 1;
2415 }
2416 }
2417
2418 if(vq->orig_msg->rep->security == sec_status_secure) {
2419 /* If the message is secure, check that all rrsets are
2420 * secure (i.e. some inserted RRset for CNAME chain with
2421 * a different signer name). And drop additional rrsets
2422 * that are not secure (if clean-additional option is set) */
2423 /* this may cause the msg to be marked bogus */
2424 val_check_nonsecure(qstate->env, vq->orig_msg->rep);
2425 if(vq->orig_msg->rep->security == sec_status_secure) {
2426 log_query_info(VERB_DETAIL, "validation success",
2427 &qstate->qinfo);
2428 if(!qstate->no_cache_store) {
2429 val_neg_addreply(qstate->env->neg_cache,
2430 vq->orig_msg->rep);
2431 }
2432 }
2433 }
2434
2435 /* if the result is bogus - set message ttl to bogus ttl to avoid
2436 * endless bogus revalidation */
2437 if(vq->orig_msg->rep->security == sec_status_bogus) {
2438 struct msgreply_entry* e;
2439
2440 /* see if we can try again to fetch data */
2441 if(vq->restart_count < ve->max_restart) {
2442 verbose(VERB_ALGO, "validation failed, "
2443 "blacklist and retry to fetch data");
2444 val_blacklist(&qstate->blacklist, qstate->region,
2445 qstate->reply_origin, 0);
2446 qstate->reply_origin = NULL;
2447 qstate->errinf = NULL;
2448 val_restart(vq);
2449 verbose(VERB_ALGO, "pass back to next module");
2450 qstate->ext_state[id] = module_restart_next;
2451 return 0;
2452 }
2453
2454 if(qstate->env->cfg->serve_expired &&
2455 (e=msg_cache_lookup(qstate->env, qstate->qinfo.qname,
2456 qstate->qinfo.qname_len, qstate->qinfo.qtype,
2457 qstate->qinfo.qclass, qstate->query_flags,
2458 0 /*now; allow expired*/,
2459 1 /*wr; we may update the data*/))) {
2460 struct reply_info* rep = (struct reply_info*)e->entry.data;
2461 if(rep && rep->security > sec_status_bogus &&
2462 (!qstate->env->cfg->serve_expired_ttl ||
2463 qstate->env->cfg->serve_expired_ttl_reset ||
2464 *qstate->env->now <= rep->serve_expired_ttl)) {
2465 verbose(VERB_ALGO, "validation failed but "
2466 "previously cached valid response "
2467 "exists; set serve-expired-norec-ttl "
2468 "for response in cache");
2469 rep->serve_expired_norec_ttl = NORR_TTL +
2470 *qstate->env->now;
2471 if(qstate->env->cfg->serve_expired_ttl_reset &&
2472 *qstate->env->now + qstate->env->cfg->serve_expired_ttl
2473 > rep->serve_expired_ttl) {
2474 verbose(VERB_ALGO, "reset serve-expired-ttl for "
2475 "valid response in cache");
2476 rep->serve_expired_ttl = *qstate->env->now +
2477 qstate->env->cfg->serve_expired_ttl;
2478 }
2479 /* Return an error response.
2480 * If serve-expired-client-timeout is enabled,
2481 * the client-timeout logic will try to find an
2482 * (expired) answer in the cache as last
2483 * resort. If it is not enabled, expired
2484 * answers are already used before the mesh
2485 * activation. */
2486 qstate->return_rcode = LDNS_RCODE_SERVFAIL;
2487 qstate->return_msg = NULL;
2488 qstate->ext_state[id] = module_finished;
2489 lock_rw_unlock(&e->entry.lock);
2490 return 0;
2491 }
2492 lock_rw_unlock(&e->entry.lock);
2493 }
2494
2495 vq->orig_msg->rep->ttl = ve->bogus_ttl;
2496 vq->orig_msg->rep->prefetch_ttl =
2497 PREFETCH_TTL_CALC(vq->orig_msg->rep->ttl);
2498 vq->orig_msg->rep->serve_expired_ttl =
2499 vq->orig_msg->rep->ttl + qstate->env->cfg->serve_expired_ttl;
2500 if((qstate->env->cfg->val_log_level >= 1 ||
2501 qstate->env->cfg->log_servfail) &&
2502 !qstate->env->cfg->val_log_squelch) {
2503 if(qstate->env->cfg->val_log_level < 2 &&
2504 !qstate->env->cfg->log_servfail)
2505 log_query_info(NO_VERBOSE, "validation failure",
2506 &qstate->qinfo);
2507 else {
2508 char* err_str = errinf_to_str_bogus(qstate,
2509 qstate->region);
2510 if(err_str) {
2511 log_info("%s", err_str);
2512 vq->orig_msg->rep->reason_bogus_str = err_str;
2513 }
2514 }
2515 }
2516 /*
2517 * If set, the validator will not make messages bogus, instead
2518 * indeterminate is issued, so that no clients receive SERVFAIL.
2519 * This allows an operator to run validation 'shadow' without
2520 * hurting responses to clients.
2521 */
2522 /* If we are in permissive mode, bogus gets indeterminate */
2523 if(qstate->env->cfg->val_permissive_mode)
2524 vq->orig_msg->rep->security = sec_status_indeterminate;
2525 }
2526
2527 if(vq->orig_msg->rep->security == sec_status_secure &&
2528 qstate->env->cfg->root_key_sentinel &&
2529 (qstate->qinfo.qtype == LDNS_RR_TYPE_A ||
2530 qstate->qinfo.qtype == LDNS_RR_TYPE_AAAA)) {
2531 char* keytag_start;
2532 uint16_t keytag;
2533 if(*qstate->qinfo.qname == strlen(SENTINEL_IS) +
2534 SENTINEL_KEYTAG_LEN &&
2535 dname_lab_startswith(qstate->qinfo.qname, SENTINEL_IS,
2536 &keytag_start)) {
2537 if(sentinel_get_keytag(keytag_start, &keytag) &&
2538 !anchor_has_keytag(qstate->env->anchors,
2539 (uint8_t*)"", 1, 0, vq->qchase.qclass, keytag)) {
2540 vq->orig_msg->rep->security =
2541 sec_status_secure_sentinel_fail;
2542 }
2543 } else if(*qstate->qinfo.qname == strlen(SENTINEL_NOT) +
2544 SENTINEL_KEYTAG_LEN &&
2545 dname_lab_startswith(qstate->qinfo.qname, SENTINEL_NOT,
2546 &keytag_start)) {
2547 if(sentinel_get_keytag(keytag_start, &keytag) &&
2548 anchor_has_keytag(qstate->env->anchors,
2549 (uint8_t*)"", 1, 0, vq->qchase.qclass, keytag)) {
2550 vq->orig_msg->rep->security =
2551 sec_status_secure_sentinel_fail;
2552 }
2553 }
2554 }
2555
2556 /* Update rep->reason_bogus as it is the one being cached */
2557 update_reason_bogus(vq->orig_msg->rep, errinf_to_reason_bogus(qstate));
2558 /* store results in cache */
2559 if(qstate->query_flags&BIT_RD) {
2560 /* if secure, this will override cache anyway, no need
2561 * to check if from parentNS */
2562 if(!qstate->no_cache_store) {
2563 if(!dns_cache_store(qstate->env, &vq->orig_msg->qinfo,
2564 vq->orig_msg->rep, 0, qstate->prefetch_leeway,
2565 0, qstate->region, qstate->query_flags,
2566 qstate->qstarttime)) {
2567 log_err("out of memory caching validator results");
2568 }
2569 }
2570 } else {
2571 /* for a referral, store the verified RRsets */
2572 /* and this does not get prefetched, so no leeway */
2573 if(!dns_cache_store(qstate->env, &vq->orig_msg->qinfo,
2574 vq->orig_msg->rep, 1, 0, 0, qstate->region,
2575 qstate->query_flags, qstate->qstarttime)) {
2576 log_err("out of memory caching validator results");
2577 }
2578 }
2579 qstate->return_rcode = LDNS_RCODE_NOERROR;
2580 qstate->return_msg = vq->orig_msg;
2581 qstate->ext_state[id] = module_finished;
2582 return 0;
2583 }
2584
2585 /**
2586 * Handle validator state.
2587 * If a method returns true, the next state is started. If false, then
2588 * processing will stop.
2589 * @param qstate: query state.
2590 * @param vq: validator query state.
2591 * @param ve: validator shared global environment.
2592 * @param id: module id.
2593 */
2594 static void
val_handle(struct module_qstate * qstate,struct val_qstate * vq,struct val_env * ve,int id)2595 val_handle(struct module_qstate* qstate, struct val_qstate* vq,
2596 struct val_env* ve, int id)
2597 {
2598 int cont = 1;
2599 while(cont) {
2600 verbose(VERB_ALGO, "val handle processing q with state %s",
2601 val_state_to_string(vq->state));
2602 switch(vq->state) {
2603 case VAL_INIT_STATE:
2604 cont = processInit(qstate, vq, ve, id);
2605 break;
2606 case VAL_FINDKEY_STATE:
2607 cont = processFindKey(qstate, vq, id);
2608 break;
2609 case VAL_VALIDATE_STATE:
2610 cont = processValidate(qstate, vq, ve, id);
2611 break;
2612 case VAL_FINISHED_STATE:
2613 cont = processFinished(qstate, vq, ve, id);
2614 break;
2615 default:
2616 log_warn("validator: invalid state %d",
2617 vq->state);
2618 cont = 0;
2619 break;
2620 }
2621 }
2622 }
2623
2624 void
val_operate(struct module_qstate * qstate,enum module_ev event,int id,struct outbound_entry * outbound)2625 val_operate(struct module_qstate* qstate, enum module_ev event, int id,
2626 struct outbound_entry* outbound)
2627 {
2628 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id];
2629 struct val_qstate* vq = (struct val_qstate*)qstate->minfo[id];
2630 verbose(VERB_QUERY, "validator[module %d] operate: extstate:%s "
2631 "event:%s", id, strextstate(qstate->ext_state[id]),
2632 strmodulevent(event));
2633 log_query_info(VERB_QUERY, "validator operate: query",
2634 &qstate->qinfo);
2635 if(vq && qstate->qinfo.qname != vq->qchase.qname)
2636 log_query_info(VERB_QUERY, "validator operate: chased to",
2637 &vq->qchase);
2638 (void)outbound;
2639 if(event == module_event_new ||
2640 (event == module_event_pass && vq == NULL)) {
2641
2642 /* pass request to next module, to get it */
2643 verbose(VERB_ALGO, "validator: pass to next module");
2644 qstate->ext_state[id] = module_wait_module;
2645 return;
2646 }
2647 if(event == module_event_moddone) {
2648 /* check if validation is needed */
2649 verbose(VERB_ALGO, "validator: nextmodule returned");
2650
2651 if(!needs_validation(qstate, qstate->return_rcode,
2652 qstate->return_msg)) {
2653 /* no need to validate this */
2654 if(qstate->return_msg)
2655 qstate->return_msg->rep->security =
2656 sec_status_indeterminate;
2657 qstate->ext_state[id] = module_finished;
2658 return;
2659 }
2660 if(already_validated(qstate->return_msg)) {
2661 qstate->ext_state[id] = module_finished;
2662 return;
2663 }
2664 if(qstate->rpz_applied) {
2665 verbose(VERB_ALGO, "rpz applied, mark it as insecure");
2666 if(qstate->return_msg)
2667 qstate->return_msg->rep->security =
2668 sec_status_insecure;
2669 qstate->ext_state[id] = module_finished;
2670 return;
2671 }
2672 /* qclass ANY should have validation result from spawned
2673 * queries. If we get here, it is bogus or an internal error */
2674 if(qstate->qinfo.qclass == LDNS_RR_CLASS_ANY) {
2675 verbose(VERB_ALGO, "cannot validate classANY: bogus");
2676 if(qstate->return_msg) {
2677 qstate->return_msg->rep->security =
2678 sec_status_bogus;
2679 update_reason_bogus(qstate->return_msg->rep, LDNS_EDE_DNSSEC_BOGUS);
2680 }
2681 qstate->ext_state[id] = module_finished;
2682 return;
2683 }
2684 /* create state to start validation */
2685 qstate->ext_state[id] = module_error; /* override this */
2686 if(!vq) {
2687 vq = val_new(qstate, id);
2688 if(!vq) {
2689 log_err("validator: malloc failure");
2690 qstate->ext_state[id] = module_error;
2691 return;
2692 }
2693 } else if(!vq->orig_msg) {
2694 if(!val_new_getmsg(qstate, vq)) {
2695 log_err("validator: malloc failure");
2696 qstate->ext_state[id] = module_error;
2697 return;
2698 }
2699 }
2700 val_handle(qstate, vq, ve, id);
2701 return;
2702 }
2703 if(event == module_event_pass) {
2704 qstate->ext_state[id] = module_error; /* override this */
2705 /* continue processing, since val_env exists */
2706 val_handle(qstate, vq, ve, id);
2707 return;
2708 }
2709 log_err("validator: bad event %s", strmodulevent(event));
2710 qstate->ext_state[id] = module_error;
2711 return;
2712 }
2713
2714 /**
2715 * Evaluate the response to a priming request.
2716 *
2717 * @param dnskey_rrset: DNSKEY rrset (can be NULL if none) in prime reply.
2718 * (this rrset is allocated in the wrong region, not the qstate).
2719 * @param ta: trust anchor.
2720 * @param qstate: qstate that needs key.
2721 * @param id: module id.
2722 * @param sub_qstate: the sub query state, that is the lookup that fetched
2723 * the trust anchor data, it contains error information for the answer.
2724 * @return new key entry or NULL on allocation failure.
2725 * The key entry will either contain a validated DNSKEY rrset, or
2726 * represent a Null key (query failed, but validation did not), or a
2727 * Bad key (validation failed).
2728 */
2729 static struct key_entry_key*
primeResponseToKE(struct ub_packed_rrset_key * dnskey_rrset,struct trust_anchor * ta,struct module_qstate * qstate,int id,struct module_qstate * sub_qstate)2730 primeResponseToKE(struct ub_packed_rrset_key* dnskey_rrset,
2731 struct trust_anchor* ta, struct module_qstate* qstate, int id,
2732 struct module_qstate* sub_qstate)
2733 {
2734 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id];
2735 struct key_entry_key* kkey = NULL;
2736 enum sec_status sec = sec_status_unchecked;
2737 char reasonbuf[256];
2738 char* reason = NULL;
2739 sldns_ede_code reason_bogus = LDNS_EDE_DNSSEC_BOGUS;
2740 int downprot = qstate->env->cfg->harden_algo_downgrade;
2741
2742 if(!dnskey_rrset) {
2743 char* err = errinf_to_str_misc(sub_qstate);
2744 char rstr[1024];
2745 log_nametypeclass(VERB_OPS, "failed to prime trust anchor -- "
2746 "could not fetch DNSKEY rrset",
2747 ta->name, LDNS_RR_TYPE_DNSKEY, ta->dclass);
2748 reason_bogus = LDNS_EDE_DNSKEY_MISSING;
2749 if(!err) {
2750 snprintf(rstr, sizeof(rstr), "no DNSKEY rrset");
2751 } else {
2752 snprintf(rstr, sizeof(rstr), "no DNSKEY rrset "
2753 "[%s]", err);
2754 }
2755 if(qstate->env->cfg->harden_dnssec_stripped) {
2756 errinf_ede(qstate, rstr, reason_bogus);
2757 kkey = key_entry_create_bad(qstate->region, ta->name,
2758 ta->namelen, ta->dclass, BOGUS_KEY_TTL,
2759 reason_bogus, rstr, *qstate->env->now);
2760 } else kkey = key_entry_create_null(qstate->region, ta->name,
2761 ta->namelen, ta->dclass, NULL_KEY_TTL,
2762 reason_bogus, rstr, *qstate->env->now);
2763 if(!kkey) {
2764 log_err("out of memory: allocate fail prime key");
2765 return NULL;
2766 }
2767 return kkey;
2768 }
2769 /* attempt to verify with trust anchor DS and DNSKEY */
2770 kkey = val_verify_new_DNSKEYs_with_ta(qstate->region, qstate->env, ve,
2771 dnskey_rrset, ta->ds_rrset, ta->dnskey_rrset, downprot,
2772 &reason, &reason_bogus, qstate, reasonbuf, sizeof(reasonbuf));
2773 if(!kkey) {
2774 log_err("out of memory: verifying prime TA");
2775 return NULL;
2776 }
2777 if(key_entry_isgood(kkey))
2778 sec = sec_status_secure;
2779 else
2780 sec = sec_status_bogus;
2781 verbose(VERB_DETAIL, "validate keys with anchor(DS): %s",
2782 sec_status_to_string(sec));
2783
2784 if(sec != sec_status_secure) {
2785 log_nametypeclass(VERB_OPS, "failed to prime trust anchor -- "
2786 "DNSKEY rrset is not secure",
2787 ta->name, LDNS_RR_TYPE_DNSKEY, ta->dclass);
2788 /* NOTE: in this case, we should probably reject the trust
2789 * anchor for longer, perhaps forever. */
2790 if(qstate->env->cfg->harden_dnssec_stripped) {
2791 errinf_ede(qstate, reason, reason_bogus);
2792 kkey = key_entry_create_bad(qstate->region, ta->name,
2793 ta->namelen, ta->dclass, BOGUS_KEY_TTL,
2794 reason_bogus, reason,
2795 *qstate->env->now);
2796 } else kkey = key_entry_create_null(qstate->region, ta->name,
2797 ta->namelen, ta->dclass, NULL_KEY_TTL,
2798 reason_bogus, reason,
2799 *qstate->env->now);
2800 if(!kkey) {
2801 log_err("out of memory: allocate null prime key");
2802 return NULL;
2803 }
2804 return kkey;
2805 }
2806
2807 log_nametypeclass(VERB_DETAIL, "Successfully primed trust anchor",
2808 ta->name, LDNS_RR_TYPE_DNSKEY, ta->dclass);
2809 return kkey;
2810 }
2811
2812 /**
2813 * In inform supers, with the resulting message and rcode and the current
2814 * keyset in the super state, validate the DS response, returning a KeyEntry.
2815 *
2816 * @param qstate: query state that is validating and asked for a DS.
2817 * @param vq: validator query state
2818 * @param id: module id.
2819 * @param rcode: rcode result value.
2820 * @param msg: result message (if rcode is OK).
2821 * @param qinfo: from the sub query state, query info.
2822 * @param ke: the key entry to return. It returns
2823 * is_bad if the DS response fails to validate, is_null if the
2824 * DS response indicated an end to secure space, is_good if the DS
2825 * validated. It returns ke=NULL if the DS response indicated that the
2826 * request wasn't a delegation point.
2827 * @param sub_qstate: the sub query state, that is the lookup that fetched
2828 * the trust anchor data, it contains error information for the answer.
2829 * Can be NULL.
2830 * @return
2831 * 0 on success,
2832 * 1 on servfail error (malloc failure),
2833 * 2 on NSEC3 suspend.
2834 */
2835 static int
ds_response_to_ke(struct module_qstate * qstate,struct val_qstate * vq,int id,int rcode,struct dns_msg * msg,struct query_info * qinfo,struct key_entry_key ** ke,struct module_qstate * sub_qstate)2836 ds_response_to_ke(struct module_qstate* qstate, struct val_qstate* vq,
2837 int id, int rcode, struct dns_msg* msg, struct query_info* qinfo,
2838 struct key_entry_key** ke, struct module_qstate* sub_qstate)
2839 {
2840 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id];
2841 char reasonbuf[256];
2842 char* reason = NULL;
2843 sldns_ede_code reason_bogus = LDNS_EDE_DNSSEC_BOGUS;
2844 enum val_classification subtype;
2845 int verified;
2846 if(rcode != LDNS_RCODE_NOERROR) {
2847 char rc[16];
2848 rc[0]=0;
2849 (void)sldns_wire2str_rcode_buf(rcode, rc, sizeof(rc));
2850 /* errors here pretty much break validation */
2851 verbose(VERB_DETAIL, "DS response was error, thus bogus");
2852 errinf(qstate, rc);
2853 reason = "no DS";
2854 if(sub_qstate) {
2855 char* err = errinf_to_str_misc(sub_qstate);
2856 if(err) {
2857 char buf[1024];
2858 snprintf(buf, sizeof(buf), "[%s]", err);
2859 errinf(qstate, buf);
2860 }
2861 }
2862 reason_bogus = LDNS_EDE_NETWORK_ERROR;
2863 errinf_ede(qstate, reason, reason_bogus);
2864 goto return_bogus;
2865 }
2866
2867 subtype = val_classify_response(BIT_RD, qinfo, qinfo, msg->rep, 0);
2868 if(subtype == VAL_CLASS_POSITIVE) {
2869 struct ub_packed_rrset_key* ds;
2870 enum sec_status sec;
2871 ds = reply_find_answer_rrset(qinfo, msg->rep);
2872 /* If there was no DS rrset, then we have mis-classified
2873 * this message. */
2874 if(!ds) {
2875 log_warn("internal error: POSITIVE DS response was "
2876 "missing DS.");
2877 reason = "no DS record";
2878 errinf_ede(qstate, reason, reason_bogus);
2879 goto return_bogus;
2880 }
2881 /* Verify only returns BOGUS or SECURE. If the rrset is
2882 * bogus, then we are done. */
2883 sec = val_verify_rrset_entry(qstate->env, ve, ds,
2884 vq->key_entry, &reason, &reason_bogus,
2885 LDNS_SECTION_ANSWER, qstate, &verified, reasonbuf,
2886 sizeof(reasonbuf));
2887 if(sec != sec_status_secure) {
2888 verbose(VERB_DETAIL, "DS rrset in DS response did "
2889 "not verify");
2890 errinf_ede(qstate, reason, reason_bogus);
2891 goto return_bogus;
2892 }
2893
2894 /* If the DS rrset validates, we still have to make sure
2895 * that they are usable. */
2896 if(!val_dsset_isusable(ds)) {
2897 /* If they aren't usable, then we treat it like
2898 * there was no DS. */
2899 *ke = key_entry_create_null(qstate->region,
2900 qinfo->qname, qinfo->qname_len, qinfo->qclass,
2901 ub_packed_rrset_ttl(ds),
2902 LDNS_EDE_UNSUPPORTED_DS_DIGEST, NULL,
2903 *qstate->env->now);
2904 return (*ke) == NULL;
2905 }
2906
2907 /* Otherwise, we return the positive response. */
2908 log_query_info(VERB_DETAIL, "validated DS", qinfo);
2909 *ke = key_entry_create_rrset(qstate->region,
2910 qinfo->qname, qinfo->qname_len, qinfo->qclass, ds,
2911 NULL, LDNS_EDE_NONE, NULL, *qstate->env->now);
2912 return (*ke) == NULL;
2913 } else if(subtype == VAL_CLASS_NODATA ||
2914 subtype == VAL_CLASS_NAMEERROR) {
2915 /* NODATA means that the qname exists, but that there was
2916 * no DS. This is a pretty normal case. */
2917 time_t proof_ttl = 0;
2918 enum sec_status sec;
2919
2920 /* make sure there are NSECs or NSEC3s with signatures */
2921 if(!val_has_signed_nsecs(msg->rep, &reason)) {
2922 verbose(VERB_ALGO, "no NSECs: %s", reason);
2923 reason_bogus = LDNS_EDE_NSEC_MISSING;
2924 errinf_ede(qstate, reason, reason_bogus);
2925 goto return_bogus;
2926 }
2927
2928 /* For subtype Name Error.
2929 * attempt ANS 2.8.1.0 compatibility where it sets rcode
2930 * to nxdomain, but really this is an Nodata/Noerror response.
2931 * Find and prove the empty nonterminal in that case */
2932
2933 /* Try to prove absence of the DS with NSEC */
2934 sec = val_nsec_prove_nodata_dsreply(
2935 qstate->env, ve, qinfo, msg->rep, vq->key_entry,
2936 &proof_ttl, &reason, &reason_bogus, qstate,
2937 reasonbuf, sizeof(reasonbuf));
2938 switch(sec) {
2939 case sec_status_secure:
2940 verbose(VERB_DETAIL, "NSEC RRset for the "
2941 "referral proved no DS.");
2942 *ke = key_entry_create_null(qstate->region,
2943 qinfo->qname, qinfo->qname_len,
2944 qinfo->qclass, proof_ttl,
2945 LDNS_EDE_NONE, NULL,
2946 *qstate->env->now);
2947 return (*ke) == NULL;
2948 case sec_status_insecure:
2949 verbose(VERB_DETAIL, "NSEC RRset for the "
2950 "referral proved not a delegation point");
2951 *ke = NULL;
2952 return 0;
2953 case sec_status_bogus:
2954 verbose(VERB_DETAIL, "NSEC RRset for the "
2955 "referral did not prove no DS.");
2956 errinf(qstate, reason);
2957 goto return_bogus;
2958 case sec_status_unchecked:
2959 default:
2960 /* NSEC proof did not work, try next */
2961 break;
2962 }
2963
2964 if(!nsec3_cache_table_init(&vq->nsec3_cache_table, qstate->region)) {
2965 log_err("malloc failure in ds_response_to_ke for "
2966 "NSEC3 cache");
2967 reason = "malloc failure";
2968 errinf_ede(qstate, reason, 0);
2969 goto return_bogus;
2970 }
2971 sec = nsec3_prove_nods(qstate->env, ve,
2972 msg->rep->rrsets + msg->rep->an_numrrsets,
2973 msg->rep->ns_numrrsets, qinfo, vq->key_entry, &reason,
2974 &reason_bogus, qstate, &vq->nsec3_cache_table,
2975 reasonbuf, sizeof(reasonbuf));
2976 switch(sec) {
2977 case sec_status_insecure:
2978 /* case insecure also continues to unsigned
2979 * space. If nsec3-iter-count too high or
2980 * optout, then treat below as unsigned */
2981 case sec_status_secure:
2982 verbose(VERB_DETAIL, "NSEC3s for the "
2983 "referral proved no DS.");
2984 *ke = key_entry_create_null(qstate->region,
2985 qinfo->qname, qinfo->qname_len,
2986 qinfo->qclass, proof_ttl,
2987 LDNS_EDE_NONE, NULL,
2988 *qstate->env->now);
2989 return (*ke) == NULL;
2990 case sec_status_indeterminate:
2991 verbose(VERB_DETAIL, "NSEC3s for the "
2992 "referral proved no delegation");
2993 *ke = NULL;
2994 return 0;
2995 case sec_status_bogus:
2996 verbose(VERB_DETAIL, "NSEC3s for the "
2997 "referral did not prove no DS.");
2998 errinf_ede(qstate, reason, reason_bogus);
2999 goto return_bogus;
3000 case sec_status_unchecked:
3001 return 2;
3002 default:
3003 /* NSEC3 proof did not work */
3004 break;
3005 }
3006
3007 /* Apparently, no available NSEC/NSEC3 proved NODATA, so
3008 * this is BOGUS. */
3009 verbose(VERB_DETAIL, "DS %s ran out of options, so return "
3010 "bogus", val_classification_to_string(subtype));
3011 reason = "no DS but also no proof of that";
3012 errinf_ede(qstate, reason, reason_bogus);
3013 goto return_bogus;
3014 } else if(subtype == VAL_CLASS_CNAME ||
3015 subtype == VAL_CLASS_CNAMENOANSWER) {
3016 /* if the CNAME matches the exact name we want and is signed
3017 * properly, then also, we are sure that no DS exists there,
3018 * much like a NODATA proof */
3019 enum sec_status sec;
3020 struct ub_packed_rrset_key* cname;
3021 cname = reply_find_rrset_section_an(msg->rep, qinfo->qname,
3022 qinfo->qname_len, LDNS_RR_TYPE_CNAME, qinfo->qclass);
3023 if(!cname) {
3024 reason = "validator classified CNAME but no "
3025 "CNAME of the queried name for DS";
3026 errinf_ede(qstate, reason, reason_bogus);
3027 goto return_bogus;
3028 }
3029 if(((struct packed_rrset_data*)cname->entry.data)->rrsig_count
3030 == 0) {
3031 if(msg->rep->an_numrrsets != 0 && ntohs(msg->rep->
3032 rrsets[0]->rk.type)==LDNS_RR_TYPE_DNAME) {
3033 reason = "DS got DNAME answer";
3034 } else {
3035 reason = "DS got unsigned CNAME answer";
3036 }
3037 errinf_ede(qstate, reason, reason_bogus);
3038 goto return_bogus;
3039 }
3040 sec = val_verify_rrset_entry(qstate->env, ve, cname,
3041 vq->key_entry, &reason, &reason_bogus,
3042 LDNS_SECTION_ANSWER, qstate, &verified, reasonbuf,
3043 sizeof(reasonbuf));
3044 if(sec == sec_status_secure) {
3045 verbose(VERB_ALGO, "CNAME validated, "
3046 "proof that DS does not exist");
3047 /* and that it is not a referral point */
3048 *ke = NULL;
3049 return 0;
3050 }
3051 errinf(qstate, "CNAME in DS response was not secure.");
3052 errinf_ede(qstate, reason, reason_bogus);
3053 goto return_bogus;
3054 } else {
3055 verbose(VERB_QUERY, "Encountered an unhandled type of "
3056 "DS response, thus bogus.");
3057 errinf(qstate, "no DS and");
3058 reason = "no DS";
3059 if(FLAGS_GET_RCODE(msg->rep->flags) != LDNS_RCODE_NOERROR) {
3060 char rc[16];
3061 rc[0]=0;
3062 (void)sldns_wire2str_rcode_buf((int)FLAGS_GET_RCODE(
3063 msg->rep->flags), rc, sizeof(rc));
3064 errinf(qstate, rc);
3065 } else errinf(qstate, val_classification_to_string(subtype));
3066 errinf(qstate, "message fails to prove that");
3067 goto return_bogus;
3068 }
3069 return_bogus:
3070 *ke = key_entry_create_bad(qstate->region, qinfo->qname,
3071 qinfo->qname_len, qinfo->qclass, BOGUS_KEY_TTL,
3072 reason_bogus, reason, *qstate->env->now);
3073 return (*ke) == NULL;
3074 }
3075
3076 /**
3077 * Process DS response. Called from inform_supers.
3078 * Because it is in inform_supers, the mesh itself is busy doing callbacks
3079 * for a state that is to be deleted soon; don't touch the mesh; instead
3080 * set a state in the super, as the super will be reactivated soon.
3081 * Perform processing to determine what state to set in the super.
3082 *
3083 * @param qstate: query state that is validating and asked for a DS.
3084 * @param vq: validator query state
3085 * @param id: module id.
3086 * @param rcode: rcode result value.
3087 * @param msg: result message (if rcode is OK).
3088 * @param qinfo: from the sub query state, query info.
3089 * @param origin: the origin of msg.
3090 * @param suspend: returned true if the task takes too long and needs to
3091 * suspend to continue the effort later.
3092 * @param sub_qstate: the sub query state, that is the lookup that fetched
3093 * the trust anchor data, it contains error information for the answer.
3094 * Can be NULL.
3095 */
3096 static void
process_ds_response(struct module_qstate * qstate,struct val_qstate * vq,int id,int rcode,struct dns_msg * msg,struct query_info * qinfo,struct sock_list * origin,int * suspend,struct module_qstate * sub_qstate)3097 process_ds_response(struct module_qstate* qstate, struct val_qstate* vq,
3098 int id, int rcode, struct dns_msg* msg, struct query_info* qinfo,
3099 struct sock_list* origin, int* suspend,
3100 struct module_qstate* sub_qstate)
3101 {
3102 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id];
3103 struct key_entry_key* dske = NULL;
3104 uint8_t* olds = vq->empty_DS_name;
3105 int ret;
3106 *suspend = 0;
3107 vq->empty_DS_name = NULL;
3108 if(sub_qstate && sub_qstate->rpz_applied) {
3109 verbose(VERB_ALGO, "rpz was applied to the DS lookup, "
3110 "make it insecure");
3111 vq->key_entry = NULL;
3112 vq->state = VAL_FINISHED_STATE;
3113 vq->chase_reply->security = sec_status_insecure;
3114 return;
3115 }
3116 ret = ds_response_to_ke(qstate, vq, id, rcode, msg, qinfo, &dske,
3117 sub_qstate);
3118 if(ret != 0) {
3119 switch(ret) {
3120 case 1:
3121 log_err("malloc failure in process_ds_response");
3122 vq->key_entry = NULL; /* make it error */
3123 vq->state = VAL_VALIDATE_STATE;
3124 return;
3125 case 2:
3126 *suspend = 1;
3127 return;
3128 default:
3129 log_err("unhandled error value for ds_response_to_ke");
3130 vq->key_entry = NULL; /* make it error */
3131 vq->state = VAL_VALIDATE_STATE;
3132 return;
3133 }
3134 }
3135 if(dske == NULL) {
3136 vq->empty_DS_name = regional_alloc_init(qstate->region,
3137 qinfo->qname, qinfo->qname_len);
3138 if(!vq->empty_DS_name) {
3139 log_err("malloc failure in empty_DS_name");
3140 vq->key_entry = NULL; /* make it error */
3141 vq->state = VAL_VALIDATE_STATE;
3142 return;
3143 }
3144 vq->empty_DS_len = qinfo->qname_len;
3145 vq->chain_blacklist = NULL;
3146 /* ds response indicated that we aren't on a delegation point.
3147 * Keep the forState.state on FINDKEY. */
3148 } else if(key_entry_isgood(dske)) {
3149 vq->ds_rrset = key_entry_get_rrset(dske, qstate->region);
3150 if(!vq->ds_rrset) {
3151 log_err("malloc failure in process DS");
3152 vq->key_entry = NULL; /* make it error */
3153 vq->state = VAL_VALIDATE_STATE;
3154 return;
3155 }
3156 vq->chain_blacklist = NULL; /* fresh blacklist for next part*/
3157 /* Keep the forState.state on FINDKEY. */
3158 } else if(key_entry_isbad(dske)
3159 && vq->restart_count < ve->max_restart) {
3160 vq->empty_DS_name = olds;
3161 val_blacklist(&vq->chain_blacklist, qstate->region, origin, 1);
3162 qstate->errinf = NULL;
3163 vq->restart_count++;
3164 } else {
3165 if(key_entry_isbad(dske)) {
3166 errinf_origin(qstate, origin);
3167 errinf_dname(qstate, "for DS", qinfo->qname);
3168 }
3169 /* NOTE: the reason for the DS to be not good (that is,
3170 * either bad or null) should have been logged by
3171 * dsResponseToKE. */
3172 vq->key_entry = dske;
3173 /* The FINDKEY phase has ended, so move on. */
3174 vq->state = VAL_VALIDATE_STATE;
3175 }
3176 }
3177
3178 /**
3179 * Process DNSKEY response. Called from inform_supers.
3180 * Sets the key entry in the state.
3181 * Because it is in inform_supers, the mesh itself is busy doing callbacks
3182 * for a state that is to be deleted soon; don't touch the mesh; instead
3183 * set a state in the super, as the super will be reactivated soon.
3184 * Perform processing to determine what state to set in the super.
3185 *
3186 * @param qstate: query state that is validating and asked for a DNSKEY.
3187 * @param vq: validator query state
3188 * @param id: module id.
3189 * @param rcode: rcode result value.
3190 * @param msg: result message (if rcode is OK).
3191 * @param qinfo: from the sub query state, query info.
3192 * @param origin: the origin of msg.
3193 * @param sub_qstate: the sub query state, that is the lookup that fetched
3194 * the trust anchor data, it contains error information for the answer.
3195 */
3196 static void
process_dnskey_response(struct module_qstate * qstate,struct val_qstate * vq,int id,int rcode,struct dns_msg * msg,struct query_info * qinfo,struct sock_list * origin,struct module_qstate * sub_qstate)3197 process_dnskey_response(struct module_qstate* qstate, struct val_qstate* vq,
3198 int id, int rcode, struct dns_msg* msg, struct query_info* qinfo,
3199 struct sock_list* origin, struct module_qstate* sub_qstate)
3200 {
3201 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id];
3202 struct key_entry_key* old = vq->key_entry;
3203 struct ub_packed_rrset_key* dnskey = NULL;
3204 int downprot;
3205 char reasonbuf[256];
3206 char* reason = NULL;
3207 sldns_ede_code reason_bogus = LDNS_EDE_DNSSEC_BOGUS;
3208
3209 if(sub_qstate && sub_qstate->rpz_applied) {
3210 verbose(VERB_ALGO, "rpz was applied to the DNSKEY lookup, "
3211 "make it insecure");
3212 vq->key_entry = NULL;
3213 vq->state = VAL_FINISHED_STATE;
3214 vq->chase_reply->security = sec_status_insecure;
3215 return;
3216 }
3217
3218 if(rcode == LDNS_RCODE_NOERROR)
3219 dnskey = reply_find_answer_rrset(qinfo, msg->rep);
3220
3221 if(dnskey == NULL) {
3222 char* err;
3223 char rstr[1024];
3224 /* bad response */
3225 verbose(VERB_DETAIL, "Missing DNSKEY RRset in response to "
3226 "DNSKEY query.");
3227
3228 if(vq->restart_count < ve->max_restart) {
3229 val_blacklist(&vq->chain_blacklist, qstate->region,
3230 origin, 1);
3231 qstate->errinf = NULL;
3232 vq->restart_count++;
3233 return;
3234 }
3235 err = errinf_to_str_misc(sub_qstate);
3236 if(!err) {
3237 snprintf(rstr, sizeof(rstr), "No DNSKEY record");
3238 } else {
3239 snprintf(rstr, sizeof(rstr), "No DNSKEY record "
3240 "[%s]", err);
3241 }
3242 reason_bogus = LDNS_EDE_DNSKEY_MISSING;
3243 vq->key_entry = key_entry_create_bad(qstate->region,
3244 qinfo->qname, qinfo->qname_len, qinfo->qclass,
3245 BOGUS_KEY_TTL, reason_bogus, rstr, *qstate->env->now);
3246 if(!vq->key_entry) {
3247 log_err("alloc failure in missing dnskey response");
3248 /* key_entry is NULL for failure in Validate */
3249 }
3250 errinf_ede(qstate, rstr, reason_bogus);
3251 errinf_origin(qstate, origin);
3252 errinf_dname(qstate, "for key", qinfo->qname);
3253 vq->state = VAL_VALIDATE_STATE;
3254 return;
3255 }
3256 if(!vq->ds_rrset) {
3257 log_err("internal error: no DS rrset for new DNSKEY response");
3258 vq->key_entry = NULL;
3259 vq->state = VAL_VALIDATE_STATE;
3260 return;
3261 }
3262 downprot = qstate->env->cfg->harden_algo_downgrade;
3263 vq->key_entry = val_verify_new_DNSKEYs(qstate->region, qstate->env,
3264 ve, dnskey, vq->ds_rrset, downprot, &reason, &reason_bogus,
3265 qstate, reasonbuf, sizeof(reasonbuf));
3266
3267 if(!vq->key_entry) {
3268 log_err("out of memory in verify new DNSKEYs");
3269 vq->state = VAL_VALIDATE_STATE;
3270 return;
3271 }
3272 /* If the key entry isBad or isNull, then we can move on to the next
3273 * state. */
3274 if(!key_entry_isgood(vq->key_entry)) {
3275 if(key_entry_isbad(vq->key_entry)) {
3276 if(vq->restart_count < ve->max_restart) {
3277 val_blacklist(&vq->chain_blacklist,
3278 qstate->region, origin, 1);
3279 qstate->errinf = NULL;
3280 vq->restart_count++;
3281 vq->key_entry = old;
3282 return;
3283 }
3284 verbose(VERB_DETAIL, "Did not match a DS to a DNSKEY, "
3285 "thus bogus.");
3286 errinf_ede(qstate, reason, reason_bogus);
3287 errinf_origin(qstate, origin);
3288 errinf_dname(qstate, "for key", qinfo->qname);
3289 }
3290 vq->chain_blacklist = NULL;
3291 vq->state = VAL_VALIDATE_STATE;
3292 return;
3293 }
3294 vq->chain_blacklist = NULL;
3295 qstate->errinf = NULL;
3296
3297 /* The DNSKEY validated, so cache it as a trusted key rrset. */
3298 key_cache_insert(ve->kcache, vq->key_entry,
3299 qstate->env->cfg->val_log_level >= 2);
3300
3301 /* If good, we stay in the FINDKEY state. */
3302 log_query_info(VERB_DETAIL, "validated DNSKEY", qinfo);
3303 }
3304
3305 /**
3306 * Process prime response
3307 * Sets the key entry in the state.
3308 *
3309 * @param qstate: query state that is validating and primed a trust anchor.
3310 * @param vq: validator query state
3311 * @param id: module id.
3312 * @param rcode: rcode result value.
3313 * @param msg: result message (if rcode is OK).
3314 * @param origin: the origin of msg.
3315 * @param sub_qstate: the sub query state, that is the lookup that fetched
3316 * the trust anchor data, it contains error information for the answer.
3317 */
3318 static void
process_prime_response(struct module_qstate * qstate,struct val_qstate * vq,int id,int rcode,struct dns_msg * msg,struct sock_list * origin,struct module_qstate * sub_qstate)3319 process_prime_response(struct module_qstate* qstate, struct val_qstate* vq,
3320 int id, int rcode, struct dns_msg* msg, struct sock_list* origin,
3321 struct module_qstate* sub_qstate)
3322 {
3323 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id];
3324 struct ub_packed_rrset_key* dnskey_rrset = NULL;
3325 struct trust_anchor* ta = anchor_find(qstate->env->anchors,
3326 vq->trust_anchor_name, vq->trust_anchor_labs,
3327 vq->trust_anchor_len, vq->qchase.qclass);
3328 if(!ta) {
3329 /* trust anchor revoked, restart with less anchors */
3330 vq->state = VAL_INIT_STATE;
3331 if(!vq->trust_anchor_name)
3332 vq->state = VAL_VALIDATE_STATE; /* break a loop */
3333 vq->trust_anchor_name = NULL;
3334 return;
3335 }
3336 /* Fetch and validate the keyEntry that corresponds to the
3337 * current trust anchor. */
3338 if(rcode == LDNS_RCODE_NOERROR) {
3339 dnskey_rrset = reply_find_rrset_section_an(msg->rep,
3340 ta->name, ta->namelen, LDNS_RR_TYPE_DNSKEY,
3341 ta->dclass);
3342 }
3343
3344 if(ta->autr) {
3345 if(!autr_process_prime(qstate->env, ve, ta, dnskey_rrset,
3346 qstate)) {
3347 /* trust anchor revoked, restart with less anchors */
3348 vq->state = VAL_INIT_STATE;
3349 vq->trust_anchor_name = NULL;
3350 return;
3351 }
3352 }
3353 vq->key_entry = primeResponseToKE(dnskey_rrset, ta, qstate, id,
3354 sub_qstate);
3355 lock_basic_unlock(&ta->lock);
3356 if(vq->key_entry) {
3357 if(key_entry_isbad(vq->key_entry)
3358 && vq->restart_count < ve->max_restart) {
3359 val_blacklist(&vq->chain_blacklist, qstate->region,
3360 origin, 1);
3361 qstate->errinf = NULL;
3362 vq->restart_count++;
3363 vq->key_entry = NULL;
3364 vq->state = VAL_INIT_STATE;
3365 return;
3366 }
3367 vq->chain_blacklist = NULL;
3368 errinf_origin(qstate, origin);
3369 errinf_dname(qstate, "for trust anchor", ta->name);
3370 /* store the freshly primed entry in the cache */
3371 key_cache_insert(ve->kcache, vq->key_entry,
3372 qstate->env->cfg->val_log_level >= 2);
3373 }
3374
3375 /* If the result of the prime is a null key, skip the FINDKEY state.*/
3376 if(!vq->key_entry || key_entry_isnull(vq->key_entry) ||
3377 key_entry_isbad(vq->key_entry)) {
3378 vq->state = VAL_VALIDATE_STATE;
3379 }
3380 /* the qstate will be reactivated after inform_super is done */
3381 }
3382
3383 /*
3384 * inform validator super.
3385 *
3386 * @param qstate: query state that finished.
3387 * @param id: module id.
3388 * @param super: the qstate to inform.
3389 */
3390 void
val_inform_super(struct module_qstate * qstate,int id,struct module_qstate * super)3391 val_inform_super(struct module_qstate* qstate, int id,
3392 struct module_qstate* super)
3393 {
3394 struct val_qstate* vq = (struct val_qstate*)super->minfo[id];
3395 log_query_info(VERB_ALGO, "validator: inform_super, sub is",
3396 &qstate->qinfo);
3397 log_query_info(VERB_ALGO, "super is", &super->qinfo);
3398 if(!vq) {
3399 verbose(VERB_ALGO, "super: has no validator state");
3400 return;
3401 }
3402 if(vq->wait_prime_ta) {
3403 vq->wait_prime_ta = 0;
3404 process_prime_response(super, vq, id, qstate->return_rcode,
3405 qstate->return_msg, qstate->reply_origin, qstate);
3406 return;
3407 }
3408 if(qstate->qinfo.qtype == LDNS_RR_TYPE_DS) {
3409 int suspend;
3410 process_ds_response(super, vq, id, qstate->return_rcode,
3411 qstate->return_msg, &qstate->qinfo,
3412 qstate->reply_origin, &suspend, qstate);
3413 /* If NSEC3 was needed during validation, NULL the NSEC3 cache;
3414 * it will be re-initiated if needed later on.
3415 * Validation (and the cache table) are happening/allocated in
3416 * the super qstate whilst the RRs are allocated (and pointed
3417 * to) in this sub qstate. */
3418 if(vq->nsec3_cache_table.ct) {
3419 vq->nsec3_cache_table.ct = NULL;
3420 }
3421 if(suspend) {
3422 /* deep copy the return_msg to vq->sub_ds_msg; it will
3423 * be resumed later in the super state with the caveat
3424 * that the initial calculations will be re-caclulated
3425 * and re-suspended there before continuing. */
3426 vq->sub_ds_msg = dns_msg_deepcopy_region(
3427 qstate->return_msg, super->region);
3428 }
3429 return;
3430 } else if(qstate->qinfo.qtype == LDNS_RR_TYPE_DNSKEY) {
3431 process_dnskey_response(super, vq, id, qstate->return_rcode,
3432 qstate->return_msg, &qstate->qinfo,
3433 qstate->reply_origin, qstate);
3434 return;
3435 }
3436 log_err("internal error in validator: no inform_supers possible");
3437 }
3438
3439 void
val_clear(struct module_qstate * qstate,int id)3440 val_clear(struct module_qstate* qstate, int id)
3441 {
3442 struct val_qstate* vq;
3443 if(!qstate)
3444 return;
3445 vq = (struct val_qstate*)qstate->minfo[id];
3446 if(vq) {
3447 if(vq->suspend_timer) {
3448 comm_timer_delete(vq->suspend_timer);
3449 }
3450 }
3451 /* everything is allocated in the region, so assign NULL */
3452 qstate->minfo[id] = NULL;
3453 }
3454
3455 size_t
val_get_mem(struct module_env * env,int id)3456 val_get_mem(struct module_env* env, int id)
3457 {
3458 struct val_env* ve = (struct val_env*)env->modinfo[id];
3459 if(!ve)
3460 return 0;
3461 return sizeof(*ve) + key_cache_get_mem(ve->kcache) +
3462 val_neg_get_mem(ve->neg_cache) +
3463 sizeof(size_t)*2*ve->nsec3_keyiter_count;
3464 }
3465
3466 /**
3467 * The validator function block
3468 */
3469 static struct module_func_block val_block = {
3470 "validator",
3471 NULL, NULL, &val_init, &val_deinit, &val_operate, &val_inform_super,
3472 &val_clear, &val_get_mem
3473 };
3474
3475 struct module_func_block*
val_get_funcblock(void)3476 val_get_funcblock(void)
3477 {
3478 return &val_block;
3479 }
3480
3481 const char*
val_state_to_string(enum val_state state)3482 val_state_to_string(enum val_state state)
3483 {
3484 switch(state) {
3485 case VAL_INIT_STATE: return "VAL_INIT_STATE";
3486 case VAL_FINDKEY_STATE: return "VAL_FINDKEY_STATE";
3487 case VAL_VALIDATE_STATE: return "VAL_VALIDATE_STATE";
3488 case VAL_FINISHED_STATE: return "VAL_FINISHED_STATE";
3489 }
3490 return "UNKNOWN VALIDATOR STATE";
3491 }
3492
3493