1 /*
2 * libunbound/context.c - validating context for unbound internal use
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 the validator context structure.
40 */
41 #include "config.h"
42 #include "libunbound/context.h"
43 #include "util/module.h"
44 #include "util/config_file.h"
45 #include "util/net_help.h"
46 #include "services/modstack.h"
47 #include "services/localzone.h"
48 #include "services/cache/rrset.h"
49 #include "services/cache/infra.h"
50 #include "services/authzone.h"
51 #include "services/listen_dnsport.h"
52 #include "util/data/msgreply.h"
53 #include "util/storage/slabhash.h"
54 #include "util/edns.h"
55 #include "sldns/sbuffer.h"
56
57 int
context_finalize(struct ub_ctx * ctx)58 context_finalize(struct ub_ctx* ctx)
59 {
60 int is_rpz = 0;
61 struct config_file* cfg = ctx->env->cfg;
62 verbosity = cfg->verbosity;
63 if(ctx_logfile_overridden && !ctx->logfile_override) {
64 log_file(NULL); /* clear that override */
65 ctx_logfile_overridden = 0;
66 }
67 if(ctx->logfile_override) {
68 ctx_logfile_overridden = 1;
69 log_file(ctx->log_out);
70 } else {
71 log_init(cfg->logfile, cfg->use_syslog, NULL);
72 }
73 cfg_apply_local_port_policy(cfg, 65536);
74 config_apply(cfg);
75 if(!modstack_setup(&ctx->mods, cfg->module_conf, ctx->env))
76 return UB_INITFAIL;
77 listen_setup_locks();
78 log_edns_known_options(VERB_ALGO, ctx->env);
79 ctx->local_zones = local_zones_create();
80 if(!ctx->local_zones)
81 return UB_NOMEM;
82 if(!local_zones_apply_cfg(ctx->local_zones, cfg))
83 return UB_INITFAIL;
84 if(!auth_zones_apply_cfg(ctx->env->auth_zones, cfg, 1, &is_rpz,
85 ctx->env, &ctx->mods))
86 return UB_INITFAIL;
87 if(!edns_strings_apply_cfg(ctx->env->edns_strings, cfg))
88 return UB_INITFAIL;
89 if(!slabhash_is_size(ctx->env->msg_cache, cfg->msg_cache_size,
90 cfg->msg_cache_slabs)) {
91 slabhash_delete(ctx->env->msg_cache);
92 ctx->env->msg_cache = slabhash_create(cfg->msg_cache_slabs,
93 HASH_DEFAULT_STARTARRAY, cfg->msg_cache_size,
94 msgreply_sizefunc, query_info_compare,
95 query_entry_delete, reply_info_delete, NULL);
96 if(!ctx->env->msg_cache)
97 return UB_NOMEM;
98 }
99 ctx->env->rrset_cache = rrset_cache_adjust(ctx->env->rrset_cache,
100 ctx->env->cfg, ctx->env->alloc);
101 if(!ctx->env->rrset_cache)
102 return UB_NOMEM;
103 ctx->env->infra_cache = infra_adjust(ctx->env->infra_cache, cfg);
104 if(!ctx->env->infra_cache)
105 return UB_NOMEM;
106 ctx->finalized = 1;
107 return UB_NOERROR;
108 }
109
context_query_cmp(const void * a,const void * b)110 int context_query_cmp(const void* a, const void* b)
111 {
112 if( *(int*)a < *(int*)b )
113 return -1;
114 if( *(int*)a > *(int*)b )
115 return 1;
116 return 0;
117 }
118
119 void
context_query_delete(struct ctx_query * q)120 context_query_delete(struct ctx_query* q)
121 {
122 if(!q) return;
123 ub_resolve_free(q->res);
124 free(q->msg);
125 free(q);
126 }
127
128 /** How many times to try to find an unused query-id-number for async */
129 #define NUM_ID_TRIES 100000
130 /** find next useful id number of 0 on error */
131 static int
find_id(struct ub_ctx * ctx,int * id)132 find_id(struct ub_ctx* ctx, int* id)
133 {
134 size_t tries = 0;
135 ctx->next_querynum++;
136 while(rbtree_search(&ctx->queries, &ctx->next_querynum)) {
137 ctx->next_querynum++; /* numerical wraparound is fine */
138 if(tries++ > NUM_ID_TRIES)
139 return 0;
140 }
141 *id = ctx->next_querynum;
142 return 1;
143 }
144
145 struct ctx_query*
context_new(struct ub_ctx * ctx,const char * name,int rrtype,int rrclass,ub_callback_type cb,ub_event_callback_type cb_event,void * cbarg)146 context_new(struct ub_ctx* ctx, const char* name, int rrtype, int rrclass,
147 ub_callback_type cb, ub_event_callback_type cb_event, void* cbarg)
148 {
149 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q));
150 if(!q) return NULL;
151 lock_basic_lock(&ctx->cfglock);
152 if(!find_id(ctx, &q->querynum)) {
153 lock_basic_unlock(&ctx->cfglock);
154 free(q);
155 return NULL;
156 }
157 lock_basic_unlock(&ctx->cfglock);
158 q->node.key = &q->querynum;
159 q->async = (cb != NULL || cb_event != NULL);
160 q->cb = cb;
161 q->cb_event = cb_event;
162 q->cb_arg = cbarg;
163 q->res = (struct ub_result*)calloc(1, sizeof(*q->res));
164 if(!q->res) {
165 free(q);
166 return NULL;
167 }
168 q->res->qname = strdup(name);
169 if(!q->res->qname) {
170 free(q->res);
171 free(q);
172 return NULL;
173 }
174 q->res->qtype = rrtype;
175 q->res->qclass = rrclass;
176
177 /* add to query list */
178 lock_basic_lock(&ctx->cfglock);
179 if(q->async)
180 ctx->num_async ++;
181 (void)rbtree_insert(&ctx->queries, &q->node);
182 lock_basic_unlock(&ctx->cfglock);
183 return q;
184 }
185
186 struct alloc_cache*
context_obtain_alloc(struct ub_ctx * ctx,int locking)187 context_obtain_alloc(struct ub_ctx* ctx, int locking)
188 {
189 struct alloc_cache* a;
190 int tnum = 0;
191 if(locking) {
192 lock_basic_lock(&ctx->cfglock);
193 }
194 a = ctx->alloc_list;
195 if(a)
196 ctx->alloc_list = a->super; /* snip off list */
197 else tnum = ctx->thr_next_num++;
198 if(locking) {
199 lock_basic_unlock(&ctx->cfglock);
200 }
201 if(a) {
202 a->super = &ctx->superalloc;
203 return a;
204 }
205 a = (struct alloc_cache*)calloc(1, sizeof(*a));
206 if(!a)
207 return NULL;
208 alloc_init(a, &ctx->superalloc, tnum);
209 return a;
210 }
211
212 void
context_release_alloc(struct ub_ctx * ctx,struct alloc_cache * alloc,int locking)213 context_release_alloc(struct ub_ctx* ctx, struct alloc_cache* alloc,
214 int locking)
215 {
216 if(!ctx || !alloc)
217 return;
218 if(locking) {
219 lock_basic_lock(&ctx->cfglock);
220 }
221 alloc->super = ctx->alloc_list;
222 ctx->alloc_list = alloc;
223 if(locking) {
224 lock_basic_unlock(&ctx->cfglock);
225 }
226 }
227
228 uint8_t*
context_serialize_new_query(struct ctx_query * q,uint32_t * len)229 context_serialize_new_query(struct ctx_query* q, uint32_t* len)
230 {
231 /* format for new query is
232 * o uint32 cmd
233 * o uint32 id
234 * o uint32 type
235 * o uint32 class
236 * o rest queryname (string)
237 */
238 uint8_t* p;
239 size_t slen = strlen(q->res->qname) + 1/*end of string*/;
240 *len = sizeof(uint32_t)*4 + slen;
241 p = (uint8_t*)malloc(*len);
242 if(!p) return NULL;
243 sldns_write_uint32(p, UB_LIBCMD_NEWQUERY);
244 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
245 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)q->res->qtype);
246 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->res->qclass);
247 memmove(p+4*sizeof(uint32_t), q->res->qname, slen);
248 return p;
249 }
250
251 struct ctx_query*
context_deserialize_new_query(struct ub_ctx * ctx,uint8_t * p,uint32_t len)252 context_deserialize_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len)
253 {
254 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q));
255 if(!q) return NULL;
256 if(len < 4*sizeof(uint32_t)+1) {
257 free(q);
258 return NULL;
259 }
260 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY);
261 q->querynum = (int)sldns_read_uint32(p+sizeof(uint32_t));
262 q->node.key = &q->querynum;
263 q->async = 1;
264 q->res = (struct ub_result*)calloc(1, sizeof(*q->res));
265 if(!q->res) {
266 free(q);
267 return NULL;
268 }
269 q->res->qtype = (int)sldns_read_uint32(p+2*sizeof(uint32_t));
270 q->res->qclass = (int)sldns_read_uint32(p+3*sizeof(uint32_t));
271 q->res->qname = strdup((char*)(p+4*sizeof(uint32_t)));
272 if(!q->res->qname) {
273 free(q->res);
274 free(q);
275 return NULL;
276 }
277
278 /** add to query list */
279 ctx->num_async++;
280 (void)rbtree_insert(&ctx->queries, &q->node);
281 return q;
282 }
283
284 struct ctx_query*
context_lookup_new_query(struct ub_ctx * ctx,uint8_t * p,uint32_t len)285 context_lookup_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len)
286 {
287 struct ctx_query* q;
288 int querynum;
289 if(len < 4*sizeof(uint32_t)+1) {
290 return NULL;
291 }
292 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY);
293 querynum = (int)sldns_read_uint32(p+sizeof(uint32_t));
294 q = (struct ctx_query*)rbtree_search(&ctx->queries, &querynum);
295 if(!q) {
296 return NULL;
297 }
298 log_assert(q->async);
299 return q;
300 }
301
302 uint8_t*
context_serialize_answer(struct ctx_query * q,int err,sldns_buffer * pkt,uint32_t * len)303 context_serialize_answer(struct ctx_query* q, int err, sldns_buffer* pkt,
304 uint32_t* len)
305 {
306 /* answer format
307 * o uint32 cmd
308 * o uint32 id
309 * o uint32 error_code
310 * o uint32 msg_security
311 * o uint32 was_ratelimited
312 * o uint32 length of why_bogus string (+1 for eos); 0 absent.
313 * o why_bogus_string
314 * o the remainder is the answer msg from resolver lookup.
315 * remainder can be length 0.
316 */
317 size_t size_of_uint32s = 6 * sizeof(uint32_t);
318 size_t pkt_len = pkt?sldns_buffer_remaining(pkt):0;
319 size_t wlen = (pkt&&q->res->why_bogus)?strlen(q->res->why_bogus)+1:0;
320 uint8_t* p;
321 *len = size_of_uint32s + pkt_len + wlen;
322 p = (uint8_t*)malloc(*len);
323 if(!p) return NULL;
324 sldns_write_uint32(p, UB_LIBCMD_ANSWER);
325 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
326 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)err);
327 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->msg_security);
328 sldns_write_uint32(p+4*sizeof(uint32_t), (uint32_t)q->res->was_ratelimited);
329 sldns_write_uint32(p+5*sizeof(uint32_t), (uint32_t)wlen);
330 if(wlen > 0)
331 memmove(p+size_of_uint32s, q->res->why_bogus, wlen);
332 if(pkt_len > 0)
333 memmove(p+size_of_uint32s+wlen,
334 sldns_buffer_begin(pkt), pkt_len);
335 return p;
336 }
337
338 struct ctx_query*
context_deserialize_answer(struct ub_ctx * ctx,uint8_t * p,uint32_t len,int * err)339 context_deserialize_answer(struct ub_ctx* ctx,
340 uint8_t* p, uint32_t len, int* err)
341 {
342 size_t size_of_uint32s = 6 * sizeof(uint32_t);
343 struct ctx_query* q = NULL ;
344 int id;
345 size_t wlen;
346 if(len < size_of_uint32s) return NULL;
347 log_assert( sldns_read_uint32(p) == UB_LIBCMD_ANSWER);
348 id = (int)sldns_read_uint32(p+sizeof(uint32_t));
349 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id);
350 if(!q) return NULL;
351 *err = (int)sldns_read_uint32(p+2*sizeof(uint32_t));
352 q->msg_security = sldns_read_uint32(p+3*sizeof(uint32_t));
353 q->res->was_ratelimited = (int)sldns_read_uint32(p+4*sizeof(uint32_t));
354 wlen = (size_t)sldns_read_uint32(p+5*sizeof(uint32_t));
355 if(len > size_of_uint32s && wlen > 0) {
356 if(len >= size_of_uint32s+wlen)
357 q->res->why_bogus = (char*)memdup(
358 p+size_of_uint32s, wlen);
359 if(!q->res->why_bogus) {
360 /* pass malloc failure to the user callback */
361 q->msg_len = 0;
362 *err = UB_NOMEM;
363 return q;
364 }
365 q->res->why_bogus[wlen-1] = 0; /* zero terminated for sure */
366 }
367 if(len > size_of_uint32s+wlen) {
368 q->msg_len = len - size_of_uint32s - wlen;
369 q->msg = (uint8_t*)memdup(p+size_of_uint32s+wlen,
370 q->msg_len);
371 if(!q->msg) {
372 /* pass malloc failure to the user callback */
373 q->msg_len = 0;
374 *err = UB_NOMEM;
375 return q;
376 }
377 }
378 return q;
379 }
380
381 uint8_t*
context_serialize_cancel(struct ctx_query * q,uint32_t * len)382 context_serialize_cancel(struct ctx_query* q, uint32_t* len)
383 {
384 /* format of cancel:
385 * o uint32 cmd
386 * o uint32 async-id */
387 uint8_t* p = (uint8_t*)reallocarray(NULL, sizeof(uint32_t), 2);
388 if(!p) return NULL;
389 *len = 2*sizeof(uint32_t);
390 sldns_write_uint32(p, UB_LIBCMD_CANCEL);
391 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
392 return p;
393 }
394
context_deserialize_cancel(struct ub_ctx * ctx,uint8_t * p,uint32_t len)395 struct ctx_query* context_deserialize_cancel(struct ub_ctx* ctx,
396 uint8_t* p, uint32_t len)
397 {
398 struct ctx_query* q;
399 int id;
400 if(len != 2*sizeof(uint32_t)) return NULL;
401 log_assert( sldns_read_uint32(p) == UB_LIBCMD_CANCEL);
402 id = (int)sldns_read_uint32(p+sizeof(uint32_t));
403 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id);
404 return q;
405 }
406
407 uint8_t*
context_serialize_quit(uint32_t * len)408 context_serialize_quit(uint32_t* len)
409 {
410 uint32_t* p = (uint32_t*)malloc(sizeof(uint32_t));
411 if(!p)
412 return NULL;
413 *len = sizeof(uint32_t);
414 sldns_write_uint32(p, UB_LIBCMD_QUIT);
415 return (uint8_t*)p;
416 }
417
context_serial_getcmd(uint8_t * p,uint32_t len)418 enum ub_ctx_cmd context_serial_getcmd(uint8_t* p, uint32_t len)
419 {
420 uint32_t v;
421 if((size_t)len < sizeof(v))
422 return UB_LIBCMD_QUIT;
423 v = sldns_read_uint32(p);
424 return v;
425 }
426