1 /*
2 * daemon/acl_list.h - client access control storage for the server.
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 helps the server keep out queries from outside sources, that
40 * should not be answered.
41 */
42 #include "config.h"
43 #include "daemon/acl_list.h"
44 #include "util/regional.h"
45 #include "util/log.h"
46 #include "util/config_file.h"
47 #include "util/net_help.h"
48 #include "services/localzone.h"
49 #include "sldns/str2wire.h"
50
51 struct acl_list*
acl_list_create(void)52 acl_list_create(void)
53 {
54 struct acl_list* acl = (struct acl_list*)calloc(1,
55 sizeof(struct acl_list));
56 if(!acl)
57 return NULL;
58 acl->region = regional_create();
59 if(!acl->region) {
60 acl_list_delete(acl);
61 return NULL;
62 }
63 return acl;
64 }
65
66 void
acl_list_delete(struct acl_list * acl)67 acl_list_delete(struct acl_list* acl)
68 {
69 if(!acl)
70 return;
71 regional_destroy(acl->region);
72 free(acl);
73 }
74
75 /** insert new address into acl_list structure */
76 static struct acl_addr*
acl_list_insert(struct acl_list * acl,struct sockaddr_storage * addr,socklen_t addrlen,int net,enum acl_access control,int complain_duplicates)77 acl_list_insert(struct acl_list* acl, struct sockaddr_storage* addr,
78 socklen_t addrlen, int net, enum acl_access control,
79 int complain_duplicates)
80 {
81 struct acl_addr* node = regional_alloc_zero(acl->region,
82 sizeof(struct acl_addr));
83 if(!node)
84 return NULL;
85 node->control = control;
86 if(!addr_tree_insert(&acl->tree, &node->node, addr, addrlen, net)) {
87 if(complain_duplicates)
88 verbose(VERB_QUERY, "duplicate acl address ignored.");
89 }
90 return node;
91 }
92
93 /** apply acl_list string */
94 static int
acl_list_str_cfg(struct acl_list * acl,const char * str,const char * s2,int complain_duplicates)95 acl_list_str_cfg(struct acl_list* acl, const char* str, const char* s2,
96 int complain_duplicates)
97 {
98 struct sockaddr_storage addr;
99 int net;
100 socklen_t addrlen;
101 enum acl_access control;
102 if(strcmp(s2, "allow") == 0)
103 control = acl_allow;
104 else if(strcmp(s2, "deny") == 0)
105 control = acl_deny;
106 else if(strcmp(s2, "refuse") == 0)
107 control = acl_refuse;
108 else if(strcmp(s2, "deny_non_local") == 0)
109 control = acl_deny_non_local;
110 else if(strcmp(s2, "refuse_non_local") == 0)
111 control = acl_refuse_non_local;
112 else if(strcmp(s2, "allow_snoop") == 0)
113 control = acl_allow_snoop;
114 else if(strcmp(s2, "allow_setrd") == 0)
115 control = acl_allow_setrd;
116 else {
117 log_err("access control type %s unknown", str);
118 return 0;
119 }
120 if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) {
121 log_err("cannot parse access control: %s %s", str, s2);
122 return 0;
123 }
124 if(!acl_list_insert(acl, &addr, addrlen, net, control,
125 complain_duplicates)) {
126 log_err("out of memory");
127 return 0;
128 }
129 return 1;
130 }
131
132 /** find or create node (NULL on parse or error) */
133 static struct acl_addr*
acl_find_or_create(struct acl_list * acl,const char * str)134 acl_find_or_create(struct acl_list* acl, const char* str)
135 {
136 struct acl_addr* node;
137 struct sockaddr_storage addr;
138 int net;
139 socklen_t addrlen;
140 if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) {
141 log_err("cannot parse netblock: %s", str);
142 return NULL;
143 }
144 /* find or create node */
145 if(!(node=(struct acl_addr*)addr_tree_find(&acl->tree, &addr,
146 addrlen, net))) {
147 /* create node, type 'allow' since otherwise tags are
148 * pointless, can override with specific access-control: cfg */
149 if(!(node=(struct acl_addr*)acl_list_insert(acl, &addr,
150 addrlen, net, acl_allow, 1))) {
151 log_err("out of memory");
152 return NULL;
153 }
154 }
155 return node;
156 }
157
158 /** apply acl_tag string */
159 static int
acl_list_tags_cfg(struct acl_list * acl,const char * str,uint8_t * bitmap,size_t bitmaplen)160 acl_list_tags_cfg(struct acl_list* acl, const char* str, uint8_t* bitmap,
161 size_t bitmaplen)
162 {
163 struct acl_addr* node;
164 if(!(node=acl_find_or_create(acl, str)))
165 return 0;
166 node->taglen = bitmaplen;
167 node->taglist = regional_alloc_init(acl->region, bitmap, bitmaplen);
168 if(!node->taglist) {
169 log_err("out of memory");
170 return 0;
171 }
172 return 1;
173 }
174
175 /** apply acl_view string */
176 static int
acl_list_view_cfg(struct acl_list * acl,const char * str,const char * str2,struct views * vs)177 acl_list_view_cfg(struct acl_list* acl, const char* str, const char* str2,
178 struct views* vs)
179 {
180 struct acl_addr* node;
181 if(!(node=acl_find_or_create(acl, str)))
182 return 0;
183 node->view = views_find_view(vs, str2, 0 /* get read lock*/);
184 if(!node->view) {
185 log_err("no view with name: %s", str2);
186 return 0;
187 }
188 lock_rw_unlock(&node->view->lock);
189 return 1;
190 }
191
192 /** apply acl_tag_action string */
193 static int
acl_list_tag_action_cfg(struct acl_list * acl,struct config_file * cfg,const char * str,const char * tag,const char * action)194 acl_list_tag_action_cfg(struct acl_list* acl, struct config_file* cfg,
195 const char* str, const char* tag, const char* action)
196 {
197 struct acl_addr* node;
198 int tagid;
199 enum localzone_type t;
200 if(!(node=acl_find_or_create(acl, str)))
201 return 0;
202 /* allocate array if not yet */
203 if(!node->tag_actions) {
204 node->tag_actions = (uint8_t*)regional_alloc_zero(acl->region,
205 sizeof(*node->tag_actions)*cfg->num_tags);
206 if(!node->tag_actions) {
207 log_err("out of memory");
208 return 0;
209 }
210 node->tag_actions_size = (size_t)cfg->num_tags;
211 }
212 /* parse tag */
213 if((tagid=find_tag_id(cfg, tag)) == -1) {
214 log_err("cannot parse tag (define-tag it): %s %s", str, tag);
215 return 0;
216 }
217 if((size_t)tagid >= node->tag_actions_size) {
218 log_err("tagid too large for array %s %s", str, tag);
219 return 0;
220 }
221 if(!local_zone_str2type(action, &t)) {
222 log_err("cannot parse access control action type: %s %s %s",
223 str, tag, action);
224 return 0;
225 }
226 node->tag_actions[tagid] = (uint8_t)t;
227 return 1;
228 }
229
230 /** check wire data parse */
231 static int
check_data(const char * data,const struct config_strlist * head)232 check_data(const char* data, const struct config_strlist* head)
233 {
234 char buf[65536];
235 uint8_t rr[LDNS_RR_BUF_SIZE];
236 size_t len = sizeof(rr);
237 int res;
238 /* '.' is sufficient for validation, and it makes the call to
239 * sldns_wirerr_get_type() simpler below. */
240 snprintf(buf, sizeof(buf), "%s %s", ".", data);
241 res = sldns_str2wire_rr_buf(buf, rr, &len, NULL, 3600, NULL, 0,
242 NULL, 0);
243
244 /* Reject it if we would end up having CNAME and other data (including
245 * another CNAME) for the same tag. */
246 if(res == 0 && head) {
247 const char* err_data = NULL;
248
249 if(sldns_wirerr_get_type(rr, len, 1) == LDNS_RR_TYPE_CNAME) {
250 /* adding CNAME while other data already exists. */
251 err_data = data;
252 } else {
253 snprintf(buf, sizeof(buf), "%s %s", ".", head->str);
254 len = sizeof(rr);
255 res = sldns_str2wire_rr_buf(buf, rr, &len, NULL, 3600,
256 NULL, 0, NULL, 0);
257 if(res != 0) {
258 /* This should be impossible here as head->str
259 * has been validated, but we check it just in
260 * case. */
261 return 0;
262 }
263 if(sldns_wirerr_get_type(rr, len, 1) ==
264 LDNS_RR_TYPE_CNAME) /* already have CNAME */
265 err_data = head->str;
266 }
267 if(err_data) {
268 log_err("redirect tag data '%s' must not coexist with "
269 "other data.", err_data);
270 return 0;
271 }
272 }
273 if(res == 0)
274 return 1;
275 log_err("rr data [char %d] parse error %s",
276 (int)LDNS_WIREPARSE_OFFSET(res)-2,
277 sldns_get_errorstr_parse(res));
278 return 0;
279 }
280
281 /** apply acl_tag_data string */
282 static int
acl_list_tag_data_cfg(struct acl_list * acl,struct config_file * cfg,const char * str,const char * tag,const char * data)283 acl_list_tag_data_cfg(struct acl_list* acl, struct config_file* cfg,
284 const char* str, const char* tag, const char* data)
285 {
286 struct acl_addr* node;
287 int tagid;
288 char* dupdata;
289 if(!(node=acl_find_or_create(acl, str)))
290 return 0;
291 /* allocate array if not yet */
292 if(!node->tag_datas) {
293 node->tag_datas = (struct config_strlist**)regional_alloc_zero(
294 acl->region, sizeof(*node->tag_datas)*cfg->num_tags);
295 if(!node->tag_datas) {
296 log_err("out of memory");
297 return 0;
298 }
299 node->tag_datas_size = (size_t)cfg->num_tags;
300 }
301 /* parse tag */
302 if((tagid=find_tag_id(cfg, tag)) == -1) {
303 log_err("cannot parse tag (define-tag it): %s %s", str, tag);
304 return 0;
305 }
306 if((size_t)tagid >= node->tag_datas_size) {
307 log_err("tagid too large for array %s %s", str, tag);
308 return 0;
309 }
310
311 /* check data? */
312 if(!check_data(data, node->tag_datas[tagid])) {
313 log_err("cannot parse access-control-tag data: %s %s '%s'",
314 str, tag, data);
315 return 0;
316 }
317
318 dupdata = regional_strdup(acl->region, data);
319 if(!dupdata) {
320 log_err("out of memory");
321 return 0;
322 }
323 if(!cfg_region_strlist_insert(acl->region,
324 &(node->tag_datas[tagid]), dupdata)) {
325 log_err("out of memory");
326 return 0;
327 }
328 return 1;
329 }
330
331 /** read acl_list config */
332 static int
read_acl_list(struct acl_list * acl,struct config_file * cfg)333 read_acl_list(struct acl_list* acl, struct config_file* cfg)
334 {
335 struct config_str2list* p;
336 for(p = cfg->acls; p; p = p->next) {
337 log_assert(p->str && p->str2);
338 if(!acl_list_str_cfg(acl, p->str, p->str2, 1))
339 return 0;
340 }
341 return 1;
342 }
343
344 /** read acl tags config */
345 static int
read_acl_tags(struct acl_list * acl,struct config_file * cfg)346 read_acl_tags(struct acl_list* acl, struct config_file* cfg)
347 {
348 struct config_strbytelist* np, *p = cfg->acl_tags;
349 cfg->acl_tags = NULL;
350 while(p) {
351 log_assert(p->str && p->str2);
352 if(!acl_list_tags_cfg(acl, p->str, p->str2, p->str2len)) {
353 config_del_strbytelist(p);
354 return 0;
355 }
356 /* free the items as we go to free up memory */
357 np = p->next;
358 free(p->str);
359 free(p->str2);
360 free(p);
361 p = np;
362 }
363 return 1;
364 }
365
366 /** read acl view config */
367 static int
read_acl_view(struct acl_list * acl,struct config_file * cfg,struct views * v)368 read_acl_view(struct acl_list* acl, struct config_file* cfg, struct views* v)
369 {
370 struct config_str2list* np, *p = cfg->acl_view;
371 cfg->acl_view = NULL;
372 while(p) {
373 log_assert(p->str && p->str2);
374 if(!acl_list_view_cfg(acl, p->str, p->str2, v)) {
375 return 0;
376 }
377 /* free the items as we go to free up memory */
378 np = p->next;
379 free(p->str);
380 free(p->str2);
381 free(p);
382 p = np;
383 }
384 return 1;
385 }
386
387 /** read acl tag actions config */
388 static int
read_acl_tag_actions(struct acl_list * acl,struct config_file * cfg)389 read_acl_tag_actions(struct acl_list* acl, struct config_file* cfg)
390 {
391 struct config_str3list* p, *np;
392 p = cfg->acl_tag_actions;
393 cfg->acl_tag_actions = NULL;
394 while(p) {
395 log_assert(p->str && p->str2 && p->str3);
396 if(!acl_list_tag_action_cfg(acl, cfg, p->str, p->str2,
397 p->str3)) {
398 config_deltrplstrlist(p);
399 return 0;
400 }
401 /* free the items as we go to free up memory */
402 np = p->next;
403 free(p->str);
404 free(p->str2);
405 free(p->str3);
406 free(p);
407 p = np;
408 }
409 return 1;
410 }
411
412 /** read acl tag datas config */
413 static int
read_acl_tag_datas(struct acl_list * acl,struct config_file * cfg)414 read_acl_tag_datas(struct acl_list* acl, struct config_file* cfg)
415 {
416 struct config_str3list* p, *np;
417 p = cfg->acl_tag_datas;
418 cfg->acl_tag_datas = NULL;
419 while(p) {
420 log_assert(p->str && p->str2 && p->str3);
421 if(!acl_list_tag_data_cfg(acl, cfg, p->str, p->str2, p->str3)) {
422 config_deltrplstrlist(p);
423 return 0;
424 }
425 /* free the items as we go to free up memory */
426 np = p->next;
427 free(p->str);
428 free(p->str2);
429 free(p->str3);
430 free(p);
431 p = np;
432 }
433 return 1;
434 }
435
436 int
acl_list_apply_cfg(struct acl_list * acl,struct config_file * cfg,struct views * v)437 acl_list_apply_cfg(struct acl_list* acl, struct config_file* cfg,
438 struct views* v)
439 {
440 regional_free_all(acl->region);
441 addr_tree_init(&acl->tree);
442 if(!read_acl_list(acl, cfg))
443 return 0;
444 if(!read_acl_view(acl, cfg, v))
445 return 0;
446 if(!read_acl_tags(acl, cfg))
447 return 0;
448 if(!read_acl_tag_actions(acl, cfg))
449 return 0;
450 if(!read_acl_tag_datas(acl, cfg))
451 return 0;
452 /* insert defaults, with '0' to ignore them if they are duplicates */
453 if(!acl_list_str_cfg(acl, "0.0.0.0/0", "refuse", 0))
454 return 0;
455 if(!acl_list_str_cfg(acl, "127.0.0.0/8", "allow", 0))
456 return 0;
457 if(cfg->do_ip6) {
458 if(!acl_list_str_cfg(acl, "::0/0", "refuse", 0))
459 return 0;
460 if(!acl_list_str_cfg(acl, "::1", "allow", 0))
461 return 0;
462 if(!acl_list_str_cfg(acl, "::ffff:127.0.0.1", "allow", 0))
463 return 0;
464 }
465 addr_tree_init_parents(&acl->tree);
466 return 1;
467 }
468
469 enum acl_access
acl_get_control(struct acl_addr * acl)470 acl_get_control(struct acl_addr* acl)
471 {
472 if(acl) return acl->control;
473 return acl_deny;
474 }
475
476 struct acl_addr*
acl_addr_lookup(struct acl_list * acl,struct sockaddr_storage * addr,socklen_t addrlen)477 acl_addr_lookup(struct acl_list* acl, struct sockaddr_storage* addr,
478 socklen_t addrlen)
479 {
480 return (struct acl_addr*)addr_tree_lookup(&acl->tree,
481 addr, addrlen);
482 }
483
484 size_t
acl_list_get_mem(struct acl_list * acl)485 acl_list_get_mem(struct acl_list* acl)
486 {
487 if(!acl) return 0;
488 return sizeof(*acl) + regional_get_mem(acl->region);
489 }
490