2 * respip/respip.c - filtering response IP module
8 * This file contains a module that inspects a result of recursive resolution
9 * to see if any IP address record should trigger a special action.
10 * If applicable these actions can modify the original response.
14 #include "services/localzone.h"
15 #include "services/cache/dns.h"
16 #include "sldns/str2wire.h"
17 #include "util/config_file.h"
18 #include "util/fptr_wlist.h"
19 #include "util/module.h"
20 #include "util/net_help.h"
21 #include "util/regional.h"
22 #include "util/data/msgreply.h"
23 #include "util/storage/dnstree.h"
24 #include "respip/respip.h"
25 #include "services/view.h"
26 #include "sldns/rrdef.h"
29 * Conceptual set of IP addresses for response AAAA or A records that should
30 * trigger special actions.
33 struct regional* region;
34 struct rbtree_type ip_tree;
35 char* const* tagname; /* shallow copy of tag names, for logging */
36 int num_tags; /* number of tagname entries */
39 /** An address span with response control information */
41 /** node in address tree */
42 struct addr_tree_node node;
45 /** length of the taglist (in bytes) */
47 /** action for this address span */
48 enum respip_action action;
49 /** "local data" for this node */
50 struct ub_packed_rrset_key* data;
53 /** Subset of resp_addr.node, used for inform-variant logging */
54 struct respip_addr_info {
55 struct sockaddr_storage addr;
60 /** Query state regarding the response-ip module. */
63 * The general state. Unless CNAME chasing takes place, all processing
64 * is completed in this state without any other asynchronous event.
69 * A subquery for CNAME chasing is completed.
71 RESPIP_SUBQUERY_FINISHED
74 /** Per query state for the response-ip module. */
75 struct respip_qstate {
76 enum respip_state state;
80 respip_set_create(void)
82 struct respip_set* set = calloc(1, sizeof(*set));
85 set->region = regional_create();
90 addr_tree_init(&set->ip_tree);
95 respip_set_delete(struct respip_set* set)
99 regional_destroy(set->region);
104 respip_set_get_tree(struct respip_set* set)
108 return &set->ip_tree;
111 /** returns the node in the address tree for the specified netblock string;
112 * non-existent node will be created if 'create' is true */
113 static struct resp_addr*
114 respip_find_or_create(struct respip_set* set, const char* ipstr, int create)
116 struct resp_addr* node;
117 struct sockaddr_storage addr;
121 if(!netblockstrtoaddr(ipstr, 0, &addr, &addrlen, &net)) {
122 log_err("cannot parse netblock: '%s'", ipstr);
125 node = (struct resp_addr*)addr_tree_find(&set->ip_tree, &addr, addrlen, net);
126 if(!node && create) {
127 node = regional_alloc_zero(set->region, sizeof(*node));
129 log_err("out of memory");
132 node->action = respip_none;
133 if(!addr_tree_insert(&set->ip_tree, &node->node, &addr,
135 /* We know we didn't find it, so this should be
137 log_warn("unexpected: duplicate address: %s", ipstr);
144 respip_tag_cfg(struct respip_set* set, const char* ipstr,
145 const uint8_t* taglist, size_t taglen)
147 struct resp_addr* node;
149 if(!(node=respip_find_or_create(set, ipstr, 1)))
152 log_warn("duplicate response-address-tag for '%s', overridden.",
155 node->taglist = regional_alloc_init(set->region, taglist, taglen);
157 log_err("out of memory");
160 node->taglen = taglen;
164 /** set action for the node specified by the netblock string */
166 respip_action_cfg(struct respip_set* set, const char* ipstr,
169 struct resp_addr* node;
170 enum respip_action action;
172 if(!(node=respip_find_or_create(set, ipstr, 1)))
174 if(node->action != respip_none) {
175 log_warn("duplicate response-ip action for '%s', overridden.",
178 if(strcmp(actnstr, "deny") == 0)
179 action = respip_deny;
180 else if(strcmp(actnstr, "redirect") == 0)
181 action = respip_redirect;
182 else if(strcmp(actnstr, "inform") == 0)
183 action = respip_inform;
184 else if(strcmp(actnstr, "inform_deny") == 0)
185 action = respip_inform_deny;
186 else if(strcmp(actnstr, "always_transparent") == 0)
187 action = respip_always_transparent;
188 else if(strcmp(actnstr, "always_refuse") == 0)
189 action = respip_always_refuse;
190 else if(strcmp(actnstr, "always_nxdomain") == 0)
191 action = respip_always_nxdomain;
193 log_err("unknown response-ip action %s", actnstr);
196 node->action = action;
200 /** allocate and initialize an rrset structure; this function is based
201 * on new_local_rrset() from the localzone.c module */
202 static struct ub_packed_rrset_key*
203 new_rrset(struct regional* region, uint16_t rrtype, uint16_t rrclass)
205 struct packed_rrset_data* pd;
206 struct ub_packed_rrset_key* rrset = regional_alloc_zero(
207 region, sizeof(*rrset));
209 log_err("out of memory");
212 rrset->entry.key = rrset;
213 pd = regional_alloc_zero(region, sizeof(*pd));
215 log_err("out of memory");
218 pd->trust = rrset_trust_prim_noglue;
219 pd->security = sec_status_insecure;
220 rrset->entry.data = pd;
221 rrset->rk.dname = regional_alloc_zero(region, 1);
222 if(!rrset->rk.dname) {
223 log_err("out of memory");
226 rrset->rk.dname_len = 1;
227 rrset->rk.type = htons(rrtype);
228 rrset->rk.rrset_class = htons(rrclass);
232 /** enter local data as resource records into a response-ip node */
234 respip_enter_rr(struct regional* region, struct resp_addr* raddr,
235 const char* rrstr, const char* netblock)
238 uint16_t rrtype = 0, rrclass = 0;
240 uint8_t rr[LDNS_RR_BUF_SIZE];
241 uint8_t* rdata = NULL;
242 size_t rdata_len = 0;
245 struct packed_rrset_data* pd;
248 if(raddr->action != respip_redirect) {
249 log_err("cannot parse response-ip-data %s: response-ip "
250 "action for %s is not redirect", rrstr, netblock);
253 ret = snprintf(buf, sizeof(buf), ". %s", rrstr);
254 if(ret < 0 || ret >= (int)sizeof(buf)) {
255 strlcpy(bufshort, rrstr, sizeof(bufshort));
256 log_err("bad response-ip-data: %s...", bufshort);
259 if(!rrstr_get_rr_content(buf, &nm, &rrtype, &rrclass, &ttl, rr, sizeof(rr),
260 &rdata, &rdata_len)) {
261 log_err("bad response-ip-data: %s", rrstr);
265 sa = (struct sockaddr*)&raddr->node.addr;
266 if (rrtype == LDNS_RR_TYPE_CNAME && raddr->data) {
267 log_err("CNAME response-ip data (%s) can not co-exist with other "
268 "response-ip data for netblock %s", rrstr, netblock);
270 } else if (raddr->data &&
271 raddr->data->rk.type == htons(LDNS_RR_TYPE_CNAME)) {
272 log_err("response-ip data (%s) can not be added; CNAME response-ip "
273 "data already in place for netblock %s", rrstr, netblock);
275 } else if((rrtype != LDNS_RR_TYPE_CNAME) &&
276 ((sa->sa_family == AF_INET && rrtype != LDNS_RR_TYPE_A) ||
277 (sa->sa_family == AF_INET6 && rrtype != LDNS_RR_TYPE_AAAA))) {
278 log_err("response-ip data %s record type does not correspond "
279 "to netblock %s address family", rrstr, netblock);
284 raddr->data = new_rrset(region, rrtype, rrclass);
288 pd = raddr->data->entry.data;
289 return rrset_insert_rr(region, pd, rdata, rdata_len, ttl, rrstr);
293 respip_data_cfg(struct respip_set* set, const char* ipstr, const char* rrstr)
295 struct resp_addr* node;
297 node=respip_find_or_create(set, ipstr, 0);
298 if(!node || node->action == respip_none) {
299 log_err("cannot parse response-ip-data %s: "
300 "response-ip node for %s not found", rrstr, ipstr);
303 return respip_enter_rr(set->region, node, rrstr, ipstr);
307 respip_set_apply_cfg(struct respip_set* set, char* const* tagname, int num_tags,
308 struct config_strbytelist* respip_tags,
309 struct config_str2list* respip_actions,
310 struct config_str2list* respip_data)
312 struct config_strbytelist* p;
313 struct config_str2list* pa;
314 struct config_str2list* pd;
316 set->tagname = tagname;
317 set->num_tags = num_tags;
321 struct config_strbytelist* np = p->next;
323 log_assert(p->str && p->str2);
324 if(!respip_tag_cfg(set, p->str, p->str2, p->str2len)) {
325 config_del_strbytelist(p);
336 struct config_str2list* np = pa->next;
337 log_assert(pa->str && pa->str2);
338 if(!respip_action_cfg(set, pa->str, pa->str2)) {
339 config_deldblstrlist(pa);
350 struct config_str2list* np = pd->next;
351 log_assert(pd->str && pd->str2);
352 if(!respip_data_cfg(set, pd->str, pd->str2)) {
353 config_deldblstrlist(pd);
366 respip_global_apply_cfg(struct respip_set* set, struct config_file* cfg)
368 int ret = respip_set_apply_cfg(set, cfg->tagname, cfg->num_tags,
369 cfg->respip_tags, cfg->respip_actions, cfg->respip_data);
370 cfg->respip_data = NULL;
371 cfg->respip_actions = NULL;
372 cfg->respip_tags = NULL;
376 /** Iterate through raw view data and apply the view-specific respip
377 * configuration; at this point we should have already seen all the views,
378 * so if any of the views that respip data refer to does not exist, that's
379 * an error. This additional iteration through view configuration data
380 * is expected to not have significant performance impact (or rather, its
381 * performance impact is not expected to be prohibitive in the configuration
385 respip_views_apply_cfg(struct views* vs, struct config_file* cfg,
386 int* have_view_respip_cfg)
388 struct config_view* cv;
392 for(cv = cfg->views; cv; cv = cv->next) {
394 /** if no respip config for this view then there's
395 * nothing to do; note that even though respip data must go
396 * with respip action, we're checking for both here because
397 * we want to catch the case where the respip action is missing
398 * while the data is present */
399 if(!cv->respip_actions && !cv->respip_data)
402 if(!(v = views_find_view(vs, cv->name, 1))) {
403 log_err("view '%s' unexpectedly missing", cv->name);
407 v->respip_set = respip_set_create();
409 log_err("out of memory");
410 lock_rw_unlock(&v->lock);
414 ret = respip_set_apply_cfg(v->respip_set, NULL, 0, NULL,
415 cv->respip_actions, cv->respip_data);
416 lock_rw_unlock(&v->lock);
418 log_err("Error while applying respip configuration "
419 "for view '%s'", cv->name);
422 *have_view_respip_cfg = (*have_view_respip_cfg ||
423 v->respip_set->ip_tree.count);
424 cv->respip_actions = NULL;
425 cv->respip_data = NULL;
431 * make a deep copy of 'key' in 'region'.
432 * This is largely derived from packed_rrset_copy_region() and
433 * packed_rrset_ptr_fixup(), but differs in the following points:
435 * - It doesn't assume all data in 'key' are in a contiguous memory region.
436 * Although that would be the case in most cases, 'key' can be passed from
437 * a lower-level module and it might not build the rrset to meet the
438 * assumption. In fact, an rrset specified as response-ip-data or generated
439 * in local_data_find_tag_datas() breaks the assumption. So it would be
440 * safer not to naively rely on the assumption. On the other hand, this
441 * function ensures the copied rrset data are in a contiguous region so
442 * that it won't cause a disruption even if an upper layer module naively
443 * assumes the memory layout.
444 * - It doesn't copy RRSIGs (if any) in 'key'. The rrset will be used in
445 * a reply that was already faked, so it doesn't make much sense to provide
446 * partial sigs even if they are valid themselves.
447 * - It doesn't adjust TTLs as it basically has to be a verbatim copy of 'key'
448 * just allocated in 'region' (the assumption is necessary TTL adjustment
449 * has been already done in 'key').
451 * This function returns the copied rrset key on success, and NULL on memory
452 * allocation failure.
454 static struct ub_packed_rrset_key*
455 copy_rrset(const struct ub_packed_rrset_key* key, struct regional* region)
457 struct ub_packed_rrset_key* ck = regional_alloc(region,
458 sizeof(struct ub_packed_rrset_key));
459 struct packed_rrset_data* d;
460 struct packed_rrset_data* data = key->entry.data;
464 /* derived from packed_rrset_copy_region(), but don't use
465 * packed_rrset_sizeof() and do exclude RRSIGs */
469 memset(&ck->entry, 0, sizeof(ck->entry));
470 ck->entry.hash = key->entry.hash;
473 ck->rk.dname = regional_alloc_init(region, key->rk.dname,
478 dsize = sizeof(struct packed_rrset_data) + data->count *
479 (sizeof(size_t)+sizeof(uint8_t*)+sizeof(time_t));
480 for(i=0; i<data->count; i++)
481 dsize += data->rr_len[i];
482 d = regional_alloc(region, dsize);
489 /* derived from packed_rrset_ptr_fixup() with copying the data */
490 d->rr_len = (size_t*)((uint8_t*)d + sizeof(struct packed_rrset_data));
491 d->rr_data = (uint8_t**)&(d->rr_len[d->count]);
492 d->rr_ttl = (time_t*)&(d->rr_data[d->count]);
493 nextrdata = (uint8_t*)&(d->rr_ttl[d->count]);
494 for(i=0; i<d->count; i++) {
495 d->rr_len[i] = data->rr_len[i];
496 d->rr_ttl[i] = data->rr_ttl[i];
497 d->rr_data[i] = nextrdata;
498 memcpy(d->rr_data[i], data->rr_data[i], data->rr_len[i]);
499 nextrdata += d->rr_len[i];
506 respip_init(struct module_env* env, int id)
514 respip_deinit(struct module_env* env, int id)
520 /** Convert a packed AAAA or A RRset to sockaddr. */
522 rdata2sockaddr(const struct packed_rrset_data* rd, uint16_t rtype, size_t i,
523 struct sockaddr_storage* ss, socklen_t* addrlenp)
525 /* unbound can accept and cache odd-length AAAA/A records, so we have
526 * to validate the length. */
527 if(rtype == LDNS_RR_TYPE_A && rd->rr_len[i] == 6) {
528 struct sockaddr_in* sa4 = (struct sockaddr_in*)ss;
530 memset(sa4, 0, sizeof(*sa4));
531 sa4->sin_family = AF_INET;
532 memcpy(&sa4->sin_addr, rd->rr_data[i] + 2,
533 sizeof(sa4->sin_addr));
534 *addrlenp = sizeof(*sa4);
536 } else if(rtype == LDNS_RR_TYPE_AAAA && rd->rr_len[i] == 18) {
537 struct sockaddr_in6* sa6 = (struct sockaddr_in6*)ss;
539 memset(sa6, 0, sizeof(*sa6));
540 sa6->sin6_family = AF_INET6;
541 memcpy(&sa6->sin6_addr, rd->rr_data[i] + 2,
542 sizeof(sa6->sin6_addr));
543 *addrlenp = sizeof(*sa6);
550 * Search the given 'iptree' for response address information that matches
551 * any of the IP addresses in an AAAA or A in the answer section of the
552 * response (stored in 'rep'). If found, a pointer to the matched resp_addr
553 * structure will be returned, and '*rrset_id' is set to the index in
554 * rep->rrsets for the RRset that contains the matching IP address record
555 * (the index is normally 0, but can be larger than that if this is a CNAME
556 * chain or type-ANY response).
558 static const struct resp_addr*
559 respip_addr_lookup(const struct reply_info *rep, struct rbtree_type* iptree,
563 struct resp_addr* ra;
564 struct sockaddr_storage ss;
567 for(i=0; i<rep->an_numrrsets; i++) {
569 const struct packed_rrset_data* rd;
570 uint16_t rtype = ntohs(rep->rrsets[i]->rk.type);
572 if(rtype != LDNS_RR_TYPE_A && rtype != LDNS_RR_TYPE_AAAA)
574 rd = rep->rrsets[i]->entry.data;
575 for(j = 0; j < rd->count; j++) {
576 if(!rdata2sockaddr(rd, rtype, j, &ss, &addrlen))
578 ra = (struct resp_addr*)addr_tree_lookup(iptree, &ss,
591 * Create a new reply_info based on 'rep'. The new info is based on
592 * the passed 'rep', but ignores any rrsets except for the first 'an_numrrsets'
593 * RRsets in the answer section. These answer rrsets are copied to the
594 * new info, up to 'copy_rrsets' rrsets (which must not be larger than
595 * 'an_numrrsets'). If an_numrrsets > copy_rrsets, the remaining rrsets array
596 * entries will be kept empty so the caller can fill them later. When rrsets
597 * are copied, they are shallow copied. The caller must ensure that the
598 * copied rrsets are valid throughout its lifetime and must provide appropriate
599 * mutex if it can be shared by multiple threads.
601 static struct reply_info *
602 make_new_reply_info(const struct reply_info* rep, struct regional* region,
603 size_t an_numrrsets, size_t copy_rrsets)
605 struct reply_info* new_rep;
608 /* create a base struct. we specify 'insecure' security status as
609 * the modified response won't be DNSSEC-valid. In our faked response
610 * the authority and additional sections will be empty (except possible
611 * EDNS0 OPT RR in the additional section appended on sending it out),
612 * so the total number of RRsets is an_numrrsets. */
613 new_rep = construct_reply_info_base(region, rep->flags,
614 rep->qdcount, rep->ttl, rep->prefetch_ttl, an_numrrsets,
615 0, 0, an_numrrsets, sec_status_insecure);
618 if(!reply_info_alloc_rrset_keys(new_rep, NULL, region))
620 for(i=0; i<copy_rrsets; i++)
621 new_rep->rrsets[i] = rep->rrsets[i];
627 * See if response-ip or tag data should override the original answer rrset
628 * (which is rep->rrsets[rrset_id]) and if so override it.
629 * This is (mostly) equivalent to localzone.c:local_data_answer() but for
630 * response-ip actions.
631 * Note that this function distinguishes error conditions from "success but
632 * not overridden". This is because we want to avoid accidentally applying
633 * the "no data" action in case of error.
634 * @param raddr: address span that requires an action
635 * @param action: action to apply
636 * @param qtype: original query type
637 * @param rep: original reply message
638 * @param rrset_id: the rrset ID in 'rep' to which the action should apply
639 * @param new_repp: see respip_rewrite_reply
640 * @param tag: if >= 0 the tag ID used to determine the action and data
641 * @param tag_datas: data corresponding to 'tag'.
642 * @param tag_datas_size: size of 'tag_datas'
643 * @param tagname: array of tag names, used for logging
644 * @param num_tags: size of 'tagname', used for logging
645 * @param redirect_rrsetp: ptr to redirect record
646 * @param region: region for building new reply
647 * @return 1 if overridden, 0 if not overridden, -1 on error.
650 respip_data_answer(const struct resp_addr* raddr, enum respip_action action,
651 uint16_t qtype, const struct reply_info* rep,
652 size_t rrset_id, struct reply_info** new_repp, int tag,
653 struct config_strlist** tag_datas, size_t tag_datas_size,
654 char* const* tagname, int num_tags,
655 struct ub_packed_rrset_key** redirect_rrsetp, struct regional* region)
657 struct ub_packed_rrset_key* rp = raddr->data;
658 struct reply_info* new_rep;
659 *redirect_rrsetp = NULL;
661 if(action == respip_redirect && tag != -1 &&
662 (size_t)tag<tag_datas_size && tag_datas[tag]) {
663 struct query_info dataqinfo;
664 struct ub_packed_rrset_key r;
666 /* Extract parameters of the original answer rrset that can be
667 * rewritten below, in the form of query_info. Note that these
668 * can be different from the info of the original query if the
669 * rrset is a CNAME target.*/
670 memset(&dataqinfo, 0, sizeof(dataqinfo));
671 dataqinfo.qname = rep->rrsets[rrset_id]->rk.dname;
672 dataqinfo.qname_len = rep->rrsets[rrset_id]->rk.dname_len;
673 dataqinfo.qtype = ntohs(rep->rrsets[rrset_id]->rk.type);
674 dataqinfo.qclass = ntohs(rep->rrsets[rrset_id]->rk.rrset_class);
676 memset(&r, 0, sizeof(r));
677 if(local_data_find_tag_datas(&dataqinfo, tag_datas[tag], &r,
680 "response-ip redirect with tag data [%d] %s",
681 tag, (tag<num_tags?tagname[tag]:"null"));
682 /* use copy_rrset() to 'normalize' memory layout */
683 rp = copy_rrset(&r, region);
691 /* If we are using response-ip-data, we need to make a copy of rrset
692 * to replace the rrset's dname. Note that, unlike local data, we
693 * rename the dname for other actions than redirect. This is because
694 * response-ip-data isn't associated to any specific name. */
695 if(rp == raddr->data) {
696 rp = copy_rrset(rp, region);
699 rp->rk.dname = rep->rrsets[rrset_id]->rk.dname;
700 rp->rk.dname_len = rep->rrsets[rrset_id]->rk.dname_len;
703 /* Build a new reply with redirect rrset. We keep any preceding CNAMEs
704 * and replace the address rrset that triggers the action. If it's
705 * type ANY query, however, no other answer records should be kept
706 * (note that it can't be a CNAME chain in this case due to
708 if(qtype == LDNS_RR_TYPE_ANY)
710 new_rep = make_new_reply_info(rep, region, rrset_id + 1, rrset_id);
713 rp->rk.flags |= PACKED_RRSET_FIXEDTTL; /* avoid adjusting TTL */
714 new_rep->rrsets[rrset_id] = rp;
716 *redirect_rrsetp = rp;
722 * apply response ip action in case where no action data is provided.
723 * this is similar to localzone.c:lz_zone_answer() but simplified due to
724 * the characteristics of response ip:
725 * - 'deny' variants will be handled at the caller side
726 * - no specific processing for 'transparent' variants: unlike local zones,
727 * there is no such a case of 'no data but name existing'. so all variants
728 * just mean 'transparent if no data'.
729 * @param qtype: query type
730 * @param action: found action
734 * @param region: region for building new reply
735 * @return 1 on success, 0 on error.
738 respip_nodata_answer(uint16_t qtype, enum respip_action action,
739 const struct reply_info *rep, size_t rrset_id,
740 struct reply_info** new_repp, struct regional* region)
742 struct reply_info* new_rep;
744 if(action == respip_refuse || action == respip_always_refuse) {
745 new_rep = make_new_reply_info(rep, region, 0, 0);
748 FLAGS_SET_RCODE(new_rep->flags, LDNS_RCODE_REFUSED);
751 } else if(action == respip_static || action == respip_redirect ||
752 action == respip_always_nxdomain) {
753 /* Since we don't know about other types of the owner name,
754 * we generally return NOERROR/NODATA unless an NXDOMAIN action
755 * is explicitly specified. */
756 int rcode = (action == respip_always_nxdomain)?
757 LDNS_RCODE_NXDOMAIN:LDNS_RCODE_NOERROR;
759 /* We should empty the answer section except for any preceding
760 * CNAMEs (in that case rrset_id > 0). Type-ANY case is
761 * special as noted in respip_data_answer(). */
762 if(qtype == LDNS_RR_TYPE_ANY)
764 new_rep = make_new_reply_info(rep, region, rrset_id, rrset_id);
767 FLAGS_SET_RCODE(new_rep->flags, rcode);
775 /** Populate action info structure with the results of response-ip action
776 * processing, iff as the result of response-ip processing we are actually
777 * taking some action. Only action is set if action_only is true.
778 * Returns true on success, false on failure.
781 populate_action_info(struct respip_action_info* actinfo,
782 enum respip_action action, const struct resp_addr* raddr,
783 const struct ub_packed_rrset_key* ATTR_UNUSED(rrset),
784 int ATTR_UNUSED(tag), const struct respip_set* ATTR_UNUSED(ipset),
785 int ATTR_UNUSED(action_only), struct regional* region)
787 if(action == respip_none || !raddr)
789 actinfo->action = action;
791 /* for inform variants, make a copy of the matched address block for
792 * later logging. We make a copy to proactively avoid disruption if
793 * and when we allow a dynamic update to the respip tree. */
794 if(action == respip_inform || action == respip_inform_deny) {
795 struct respip_addr_info* a =
796 regional_alloc_zero(region, sizeof(*a));
798 log_err("out of memory");
801 a->addr = raddr->node.addr;
802 a->addrlen = raddr->node.addrlen;
803 a->net = raddr->node.net;
804 actinfo->addrinfo = a;
811 respip_rewrite_reply(const struct query_info* qinfo,
812 const struct respip_client_info* cinfo, const struct reply_info* rep,
813 struct reply_info** new_repp, struct respip_action_info* actinfo,
814 struct ub_packed_rrset_key** alias_rrset, int search_only,
815 struct regional* region)
817 const uint8_t* ctaglist;
819 const uint8_t* tag_actions;
820 size_t tag_actions_size;
821 struct config_strlist** tag_datas;
822 size_t tag_datas_size;
823 struct view* view = NULL;
824 struct respip_set* ipset = NULL;
826 enum respip_action action = respip_none;
828 const struct resp_addr* raddr = NULL;
830 struct ub_packed_rrset_key* redirect_rrset = NULL;
834 ctaglist = cinfo->taglist;
835 ctaglen = cinfo->taglen;
836 tag_actions = cinfo->tag_actions;
837 tag_actions_size = cinfo->tag_actions_size;
838 tag_datas = cinfo->tag_datas;
839 tag_datas_size = cinfo->tag_datas_size;
841 ipset = cinfo->respip_set;
843 /** Try to use response-ip config from the view first; use
844 * global response-ip config if we don't have the view or we don't
845 * have the matching per-view config (and the view allows the use
846 * of global data in this case).
847 * Note that we lock the view even if we only use view members that
848 * currently don't change after creation. This is for safety for
849 * future possible changes as the view documentation seems to expect
850 * any of its member can change in the view's lifetime.
851 * Note also that we assume 'view' is valid in this function, which
852 * should be safe (see unbound bug #1191) */
854 lock_rw_rdlock(&view->lock);
855 if(view->respip_set) {
856 if((raddr = respip_addr_lookup(rep,
857 &view->respip_set->ip_tree, &rrset_id))) {
858 /** for per-view respip directives the action
859 * can only be direct (i.e. not tag-based) */
860 action = raddr->action;
863 if(!raddr && !view->isfirst)
866 if(!raddr && ipset && (raddr = respip_addr_lookup(rep, &ipset->ip_tree,
868 action = (enum respip_action)local_data_find_tag_action(
869 raddr->taglist, raddr->taglen, ctaglist, ctaglen,
870 tag_actions, tag_actions_size,
871 (enum localzone_type)raddr->action, &tag,
872 ipset->tagname, ipset->num_tags);
874 if(raddr && !search_only) {
877 /* first, see if we have response-ip or tag action for the
878 * action except for 'always' variants. */
879 if(action != respip_always_refuse
880 && action != respip_always_transparent
881 && action != respip_always_nxdomain
882 && (result = respip_data_answer(raddr, action,
883 qinfo->qtype, rep, rrset_id, new_repp, tag, tag_datas,
884 tag_datas_size, ipset->tagname, ipset->num_tags,
885 &redirect_rrset, region)) < 0) {
890 /* if no action data applied, take action specific to the
891 * action without data. */
892 if(!result && !respip_nodata_answer(qinfo->qtype, action, rep,
893 rrset_id, new_repp, region)) {
900 lock_rw_unlock(&view->lock);
903 /* If we're redirecting the original answer to a
904 * CNAME, record the CNAME rrset so the caller can take
905 * the appropriate action. Note that we don't check the
906 * action type; it should normally be 'redirect', but it
907 * can be of other type when a data-dependent tag action
908 * uses redirect response-ip data.
911 redirect_rrset->rk.type == ntohs(LDNS_RR_TYPE_CNAME) &&
912 qinfo->qtype != LDNS_RR_TYPE_ANY)
913 *alias_rrset = redirect_rrset;
914 /* on success, populate respip result structure */
915 ret = populate_action_info(actinfo, action, raddr,
916 redirect_rrset, tag, ipset, search_only, region);
922 generate_cname_request(struct module_qstate* qstate,
923 struct ub_packed_rrset_key* alias_rrset)
925 struct module_qstate* subq = NULL;
926 struct query_info subqi;
928 memset(&subqi, 0, sizeof(subqi));
929 get_cname_target(alias_rrset, &subqi.qname, &subqi.qname_len);
931 return 0; /* unexpected: not a valid CNAME RDATA */
932 subqi.qtype = qstate->qinfo.qtype;
933 subqi.qclass = qstate->qinfo.qclass;
934 fptr_ok(fptr_whitelist_modenv_attach_sub(qstate->env->attach_sub));
935 return (*qstate->env->attach_sub)(qstate, &subqi, BIT_RD, 0, 0, &subq);
939 respip_operate(struct module_qstate* qstate, enum module_ev event, int id,
940 struct outbound_entry* outbound)
942 struct respip_qstate* rq = (struct respip_qstate*)qstate->minfo[id];
944 log_query_info(VERB_QUERY, "respip operate: query", &qstate->qinfo);
947 if(event == module_event_new || event == module_event_pass) {
949 rq = regional_alloc_zero(qstate->region, sizeof(*rq));
952 rq->state = RESPIP_INIT;
953 qstate->minfo[id] = rq;
955 if(rq->state == RESPIP_SUBQUERY_FINISHED) {
956 qstate->ext_state[id] = module_finished;
959 verbose(VERB_ALGO, "respip: pass to next module");
960 qstate->ext_state[id] = module_wait_module;
961 } else if(event == module_event_moddone) {
962 /* If the reply may be subject to response-ip rewriting
963 * according to the query type, check the actions. If a
964 * rewrite is necessary, we'll replace the reply in qstate
965 * with the new one. */
966 enum module_ext_state next_state = module_finished;
968 if((qstate->qinfo.qtype == LDNS_RR_TYPE_A ||
969 qstate->qinfo.qtype == LDNS_RR_TYPE_AAAA ||
970 qstate->qinfo.qtype == LDNS_RR_TYPE_ANY) &&
971 qstate->return_msg && qstate->return_msg->rep) {
972 struct respip_action_info actinfo = {respip_none, NULL};
973 struct reply_info* new_rep = qstate->return_msg->rep;
974 struct ub_packed_rrset_key* alias_rrset = NULL;
976 if(!respip_rewrite_reply(&qstate->qinfo,
977 qstate->client_info, qstate->return_msg->rep,
978 &new_rep, &actinfo, &alias_rrset, 0,
982 if(actinfo.action != respip_none) {
983 /* save action info for logging on a
984 * per-front-end-query basis */
985 if(!(qstate->respip_action_info =
986 regional_alloc_init(qstate->region,
987 &actinfo, sizeof(actinfo))))
989 log_err("out of memory");
993 qstate->respip_action_info = NULL;
995 if (new_rep == qstate->return_msg->rep &&
996 (actinfo.action == respip_deny ||
997 actinfo.action == respip_inform_deny)) {
998 /* for deny-variant actions (unless response-ip
999 * data is applied), mark the query state so
1000 * the response will be dropped for all
1002 qstate->is_drop = 1;
1003 } else if(alias_rrset) {
1004 if(!generate_cname_request(qstate, alias_rrset))
1006 next_state = module_wait_subquery;
1008 qstate->return_msg->rep = new_rep;
1010 qstate->ext_state[id] = next_state;
1012 qstate->ext_state[id] = module_finished;
1017 qstate->return_rcode = LDNS_RCODE_SERVFAIL;
1018 qstate->return_msg = NULL;
1022 respip_merge_cname(struct reply_info* base_rep,
1023 const struct query_info* qinfo, const struct reply_info* tgt_rep,
1024 const struct respip_client_info* cinfo, int must_validate,
1025 struct reply_info** new_repp, struct regional* region)
1027 struct reply_info* new_rep;
1028 struct reply_info* tmp_rep = NULL; /* just a placeholder */
1029 struct ub_packed_rrset_key* alias_rrset = NULL; /* ditto */
1032 struct respip_action_info actinfo = {respip_none, NULL};
1034 /* If the query for the CNAME target would result in an unusual rcode,
1035 * we generally translate it as a failure for the base query
1036 * (which would then be translated into SERVFAIL). The only exception
1037 * is NXDOMAIN and YXDOMAIN, which are passed to the end client(s).
1038 * The YXDOMAIN case would be rare but still possible (when
1039 * DNSSEC-validated DNAME has been cached but synthesizing CNAME
1040 * can't be generated due to length limitation) */
1041 tgt_rcode = FLAGS_GET_RCODE(tgt_rep->flags);
1042 if((tgt_rcode != LDNS_RCODE_NOERROR &&
1043 tgt_rcode != LDNS_RCODE_NXDOMAIN &&
1044 tgt_rcode != LDNS_RCODE_YXDOMAIN) ||
1045 (must_validate && tgt_rep->security <= sec_status_bogus)) {
1049 /* see if the target reply would be subject to a response-ip action. */
1050 if(!respip_rewrite_reply(qinfo, cinfo, tgt_rep, &tmp_rep, &actinfo,
1051 &alias_rrset, 1, region))
1053 if(actinfo.action != respip_none) {
1054 log_info("CNAME target of redirect response-ip action would "
1055 "be subject to response-ip action, too; stripped");
1056 *new_repp = base_rep;
1060 /* Append target reply to the base. Since we cannot assume
1061 * tgt_rep->rrsets is valid throughout the lifetime of new_rep
1062 * or it can be safely shared by multiple threads, we need to make a
1064 new_rep = make_new_reply_info(base_rep, region,
1065 base_rep->an_numrrsets + tgt_rep->an_numrrsets,
1066 base_rep->an_numrrsets);
1069 for(i=0,j=base_rep->an_numrrsets; i<tgt_rep->an_numrrsets; i++,j++) {
1070 new_rep->rrsets[j] = copy_rrset(tgt_rep->rrsets[i], region);
1071 if(!new_rep->rrsets[j])
1075 FLAGS_SET_RCODE(new_rep->flags, tgt_rcode);
1076 *new_repp = new_rep;
1081 respip_inform_super(struct module_qstate* qstate, int id,
1082 struct module_qstate* super)
1084 struct respip_qstate* rq = (struct respip_qstate*)super->minfo[id];
1085 struct reply_info* new_rep = NULL;
1087 rq->state = RESPIP_SUBQUERY_FINISHED;
1089 /* respip subquery should have always been created with a valid reply
1091 log_assert(super->return_msg && super->return_msg->rep);
1093 /* return_msg can be NULL when, e.g., the sub query resulted in
1094 * SERVFAIL, in which case we regard it as a failure of the original
1095 * query. Other checks are probably redundant, but we check them
1097 if(!qstate->return_msg || !qstate->return_msg->rep ||
1098 qstate->return_rcode != LDNS_RCODE_NOERROR)
1101 if(!respip_merge_cname(super->return_msg->rep, &qstate->qinfo,
1102 qstate->return_msg->rep, super->client_info,
1103 super->env->need_to_validate, &new_rep, super->region))
1105 super->return_msg->rep = new_rep;
1109 super->return_rcode = LDNS_RCODE_SERVFAIL;
1110 super->return_msg = NULL;
1115 respip_clear(struct module_qstate* qstate, int id)
1117 qstate->minfo[id] = NULL;
1121 respip_get_mem(struct module_env* env, int id)
1129 * The response-ip function block
1131 static struct module_func_block respip_block = {
1133 &respip_init, &respip_deinit, &respip_operate, &respip_inform_super,
1134 &respip_clear, &respip_get_mem
1137 struct module_func_block*
1138 respip_get_funcblock(void)
1140 return &respip_block;
1144 resp_addr_get_action(const struct resp_addr* addr)
1146 return addr ? addr->action : respip_none;
1149 struct ub_packed_rrset_key*
1150 resp_addr_get_rrset(struct resp_addr* addr)
1152 return addr ? addr->data : NULL;
1156 respip_set_is_empty(const struct respip_set* set)
1158 return set ? set->ip_tree.count == 0 : 1;
1162 respip_inform_print(struct respip_addr_info* respip_addr, uint8_t* qname,
1163 uint16_t qtype, uint16_t qclass, struct local_rrset* local_alias,
1164 struct comm_reply* repinfo)
1166 char srcip[128], respip[128], txt[512];
1170 qname = local_alias->rrset->rk.dname;
1171 port = (unsigned)((repinfo->addr.ss_family == AF_INET) ?
1172 ntohs(((struct sockaddr_in*)&repinfo->addr)->sin_port) :
1173 ntohs(((struct sockaddr_in6*)&repinfo->addr)->sin6_port));
1174 addr_to_str(&repinfo->addr, repinfo->addrlen, srcip, sizeof(srcip));
1175 addr_to_str(&respip_addr->addr, respip_addr->addrlen,
1176 respip, sizeof(respip));
1177 snprintf(txt, sizeof(txt), "%s/%d inform %s@%u", respip,
1178 respip_addr->net, srcip, port);
1179 log_nametypeclass(0, txt, qname, qtype, qclass);