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 ctx->pipe_pid = getpid();
74 cfg_apply_local_port_policy(cfg, 65536);
75 config_apply(cfg);
76 if(!modstack_setup(&ctx->mods, cfg->module_conf, ctx->env))
77 return UB_INITFAIL;
78 listen_setup_locks();
79 log_edns_known_options(VERB_ALGO, ctx->env);
80 ctx->local_zones = local_zones_create();
81 if(!ctx->local_zones)
82 return UB_NOMEM;
83 if(!local_zones_apply_cfg(ctx->local_zones, cfg))
84 return UB_INITFAIL;
85 if(!auth_zones_apply_cfg(ctx->env->auth_zones, cfg, 1, &is_rpz,
86 ctx->env, &ctx->mods))
87 return UB_INITFAIL;
88 if(!edns_strings_apply_cfg(ctx->env->edns_strings, cfg))
89 return UB_INITFAIL;
90 if(!slabhash_is_size(ctx->env->msg_cache, cfg->msg_cache_size,
91 cfg->msg_cache_slabs)) {
92 slabhash_delete(ctx->env->msg_cache);
93 ctx->env->msg_cache = slabhash_create(cfg->msg_cache_slabs,
94 HASH_DEFAULT_STARTARRAY, cfg->msg_cache_size,
95 msgreply_sizefunc, query_info_compare,
96 query_entry_delete, reply_info_delete, NULL);
97 if(!ctx->env->msg_cache)
98 return UB_NOMEM;
99 }
100 ctx->env->rrset_cache = rrset_cache_adjust(ctx->env->rrset_cache,
101 ctx->env->cfg, ctx->env->alloc);
102 if(!ctx->env->rrset_cache)
103 return UB_NOMEM;
104 ctx->env->infra_cache = infra_adjust(ctx->env->infra_cache, cfg);
105 if(!ctx->env->infra_cache)
106 return UB_NOMEM;
107 ctx->finalized = 1;
108 return UB_NOERROR;
109 }
110
context_query_cmp(const void * a,const void * b)111 int context_query_cmp(const void* a, const void* b)
112 {
113 if( *(int*)a < *(int*)b )
114 return -1;
115 if( *(int*)a > *(int*)b )
116 return 1;
117 return 0;
118 }
119
120 void
context_query_delete(struct ctx_query * q)121 context_query_delete(struct ctx_query* q)
122 {
123 if(!q) return;
124 ub_resolve_free(q->res);
125 free(q->msg);
126 free(q);
127 }
128
129 /** How many times to try to find an unused query-id-number for async */
130 #define NUM_ID_TRIES 100000
131 /** find next useful id number of 0 on error */
132 static int
find_id(struct ub_ctx * ctx,int * id)133 find_id(struct ub_ctx* ctx, int* id)
134 {
135 size_t tries = 0;
136 ctx->next_querynum++;
137 while(rbtree_search(&ctx->queries, &ctx->next_querynum)) {
138 ctx->next_querynum++; /* numerical wraparound is fine */
139 if(tries++ > NUM_ID_TRIES)
140 return 0;
141 }
142 *id = ctx->next_querynum;
143 return 1;
144 }
145
146 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)147 context_new(struct ub_ctx* ctx, const char* name, int rrtype, int rrclass,
148 ub_callback_type cb, ub_event_callback_type cb_event, void* cbarg)
149 {
150 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q));
151 if(!q) return NULL;
152 lock_basic_lock(&ctx->cfglock);
153 if(!find_id(ctx, &q->querynum)) {
154 lock_basic_unlock(&ctx->cfglock);
155 free(q);
156 return NULL;
157 }
158 lock_basic_unlock(&ctx->cfglock);
159 q->node.key = &q->querynum;
160 q->async = (cb != NULL || cb_event != NULL);
161 q->cb = cb;
162 q->cb_event = cb_event;
163 q->cb_arg = cbarg;
164 q->res = (struct ub_result*)calloc(1, sizeof(*q->res));
165 if(!q->res) {
166 free(q);
167 return NULL;
168 }
169 q->res->qname = strdup(name);
170 if(!q->res->qname) {
171 free(q->res);
172 free(q);
173 return NULL;
174 }
175 q->res->qtype = rrtype;
176 q->res->qclass = rrclass;
177
178 /* add to query list */
179 lock_basic_lock(&ctx->cfglock);
180 if(q->async)
181 ctx->num_async ++;
182 (void)rbtree_insert(&ctx->queries, &q->node);
183 lock_basic_unlock(&ctx->cfglock);
184 return q;
185 }
186
187 struct alloc_cache*
context_obtain_alloc(struct ub_ctx * ctx,int locking)188 context_obtain_alloc(struct ub_ctx* ctx, int locking)
189 {
190 struct alloc_cache* a;
191 int tnum = 0;
192 if(locking) {
193 lock_basic_lock(&ctx->cfglock);
194 }
195 a = ctx->alloc_list;
196 if(a)
197 ctx->alloc_list = a->super; /* snip off list */
198 else tnum = ctx->thr_next_num++;
199 if(locking) {
200 lock_basic_unlock(&ctx->cfglock);
201 }
202 if(a) {
203 a->super = &ctx->superalloc;
204 return a;
205 }
206 a = (struct alloc_cache*)calloc(1, sizeof(*a));
207 if(!a)
208 return NULL;
209 alloc_init(a, &ctx->superalloc, tnum);
210 return a;
211 }
212
213 void
context_release_alloc(struct ub_ctx * ctx,struct alloc_cache * alloc,int locking)214 context_release_alloc(struct ub_ctx* ctx, struct alloc_cache* alloc,
215 int locking)
216 {
217 if(!ctx || !alloc)
218 return;
219 if(locking) {
220 lock_basic_lock(&ctx->cfglock);
221 }
222 alloc->super = ctx->alloc_list;
223 ctx->alloc_list = alloc;
224 if(locking) {
225 lock_basic_unlock(&ctx->cfglock);
226 }
227 }
228
229 uint8_t*
context_serialize_new_query(struct ctx_query * q,uint32_t * len)230 context_serialize_new_query(struct ctx_query* q, uint32_t* len)
231 {
232 /* format for new query is
233 * o uint32 cmd
234 * o uint32 id
235 * o uint32 type
236 * o uint32 class
237 * o rest queryname (string)
238 */
239 uint8_t* p;
240 size_t slen = strlen(q->res->qname) + 1/*end of string*/;
241 *len = sizeof(uint32_t)*4 + slen;
242 p = (uint8_t*)malloc(*len);
243 if(!p) return NULL;
244 sldns_write_uint32(p, UB_LIBCMD_NEWQUERY);
245 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
246 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)q->res->qtype);
247 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->res->qclass);
248 memmove(p+4*sizeof(uint32_t), q->res->qname, slen);
249 return p;
250 }
251
252 struct ctx_query*
context_deserialize_new_query(struct ub_ctx * ctx,uint8_t * p,uint32_t len)253 context_deserialize_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len)
254 {
255 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q));
256 if(!q) return NULL;
257 if(len < 4*sizeof(uint32_t)+1) {
258 free(q);
259 return NULL;
260 }
261 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY);
262 q->querynum = (int)sldns_read_uint32(p+sizeof(uint32_t));
263 q->node.key = &q->querynum;
264 q->async = 1;
265 q->res = (struct ub_result*)calloc(1, sizeof(*q->res));
266 if(!q->res) {
267 free(q);
268 return NULL;
269 }
270 q->res->qtype = (int)sldns_read_uint32(p+2*sizeof(uint32_t));
271 q->res->qclass = (int)sldns_read_uint32(p+3*sizeof(uint32_t));
272 q->res->qname = strdup((char*)(p+4*sizeof(uint32_t)));
273 if(!q->res->qname) {
274 free(q->res);
275 free(q);
276 return NULL;
277 }
278
279 /** add to query list */
280 ctx->num_async++;
281 (void)rbtree_insert(&ctx->queries, &q->node);
282 return q;
283 }
284
285 struct ctx_query*
context_lookup_new_query(struct ub_ctx * ctx,uint8_t * p,uint32_t len)286 context_lookup_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len)
287 {
288 struct ctx_query* q;
289 int querynum;
290 if(len < 4*sizeof(uint32_t)+1) {
291 return NULL;
292 }
293 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY);
294 querynum = (int)sldns_read_uint32(p+sizeof(uint32_t));
295 q = (struct ctx_query*)rbtree_search(&ctx->queries, &querynum);
296 if(!q) {
297 return NULL;
298 }
299 log_assert(q->async);
300 return q;
301 }
302
303 uint8_t*
context_serialize_answer(struct ctx_query * q,int err,sldns_buffer * pkt,uint32_t * len)304 context_serialize_answer(struct ctx_query* q, int err, sldns_buffer* pkt,
305 uint32_t* len)
306 {
307 /* answer format
308 * o uint32 cmd
309 * o uint32 id
310 * o uint32 error_code
311 * o uint32 msg_security
312 * o uint32 was_ratelimited
313 * o uint32 length of why_bogus string (+1 for eos); 0 absent.
314 * o why_bogus_string
315 * o the remainder is the answer msg from resolver lookup.
316 * remainder can be length 0.
317 */
318 size_t size_of_uint32s = 6 * sizeof(uint32_t);
319 size_t pkt_len = pkt?sldns_buffer_remaining(pkt):0;
320 size_t wlen = (pkt&&q->res->why_bogus)?strlen(q->res->why_bogus)+1:0;
321 uint8_t* p;
322 *len = size_of_uint32s + pkt_len + wlen;
323 p = (uint8_t*)malloc(*len);
324 if(!p) return NULL;
325 sldns_write_uint32(p, UB_LIBCMD_ANSWER);
326 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
327 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)err);
328 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->msg_security);
329 sldns_write_uint32(p+4*sizeof(uint32_t), (uint32_t)q->res->was_ratelimited);
330 sldns_write_uint32(p+5*sizeof(uint32_t), (uint32_t)wlen);
331 if(wlen > 0)
332 memmove(p+size_of_uint32s, q->res->why_bogus, wlen);
333 if(pkt_len > 0)
334 memmove(p+size_of_uint32s+wlen,
335 sldns_buffer_begin(pkt), pkt_len);
336 return p;
337 }
338
339 struct ctx_query*
context_deserialize_answer(struct ub_ctx * ctx,uint8_t * p,uint32_t len,int * err)340 context_deserialize_answer(struct ub_ctx* ctx,
341 uint8_t* p, uint32_t len, int* err)
342 {
343 size_t size_of_uint32s = 6 * sizeof(uint32_t);
344 struct ctx_query* q = NULL ;
345 int id;
346 size_t wlen;
347 if(len < size_of_uint32s) return NULL;
348 log_assert( sldns_read_uint32(p) == UB_LIBCMD_ANSWER);
349 id = (int)sldns_read_uint32(p+sizeof(uint32_t));
350 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id);
351 if(!q) return NULL;
352 *err = (int)sldns_read_uint32(p+2*sizeof(uint32_t));
353 q->msg_security = sldns_read_uint32(p+3*sizeof(uint32_t));
354 q->res->was_ratelimited = (int)sldns_read_uint32(p+4*sizeof(uint32_t));
355 wlen = (size_t)sldns_read_uint32(p+5*sizeof(uint32_t));
356 if(len > size_of_uint32s && wlen > 0) {
357 if(len >= size_of_uint32s+wlen)
358 q->res->why_bogus = (char*)memdup(
359 p+size_of_uint32s, wlen);
360 if(!q->res->why_bogus) {
361 /* pass malloc failure to the user callback */
362 q->msg_len = 0;
363 *err = UB_NOMEM;
364 return q;
365 }
366 q->res->why_bogus[wlen-1] = 0; /* zero terminated for sure */
367 }
368 if(len > size_of_uint32s+wlen) {
369 q->msg_len = len - size_of_uint32s - wlen;
370 q->msg = (uint8_t*)memdup(p+size_of_uint32s+wlen,
371 q->msg_len);
372 if(!q->msg) {
373 /* pass malloc failure to the user callback */
374 q->msg_len = 0;
375 *err = UB_NOMEM;
376 return q;
377 }
378 }
379 return q;
380 }
381
382 uint8_t*
context_serialize_cancel(struct ctx_query * q,uint32_t * len)383 context_serialize_cancel(struct ctx_query* q, uint32_t* len)
384 {
385 /* format of cancel:
386 * o uint32 cmd
387 * o uint32 async-id */
388 uint8_t* p = (uint8_t*)reallocarray(NULL, sizeof(uint32_t), 2);
389 if(!p) return NULL;
390 *len = 2*sizeof(uint32_t);
391 sldns_write_uint32(p, UB_LIBCMD_CANCEL);
392 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
393 return p;
394 }
395
context_deserialize_cancel(struct ub_ctx * ctx,uint8_t * p,uint32_t len)396 struct ctx_query* context_deserialize_cancel(struct ub_ctx* ctx,
397 uint8_t* p, uint32_t len)
398 {
399 struct ctx_query* q;
400 int id;
401 if(len != 2*sizeof(uint32_t)) return NULL;
402 log_assert( sldns_read_uint32(p) == UB_LIBCMD_CANCEL);
403 id = (int)sldns_read_uint32(p+sizeof(uint32_t));
404 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id);
405 return q;
406 }
407
408 uint8_t*
context_serialize_quit(uint32_t * len)409 context_serialize_quit(uint32_t* len)
410 {
411 uint32_t* p = (uint32_t*)malloc(sizeof(uint32_t));
412 if(!p)
413 return NULL;
414 *len = sizeof(uint32_t);
415 sldns_write_uint32(p, UB_LIBCMD_QUIT);
416 return (uint8_t*)p;
417 }
418
context_serial_getcmd(uint8_t * p,uint32_t len)419 enum ub_ctx_cmd context_serial_getcmd(uint8_t* p, uint32_t len)
420 {
421 uint32_t v;
422 if((size_t)len < sizeof(v))
423 return UB_LIBCMD_QUIT;
424 v = sldns_read_uint32(p);
425 return v;
426 }
427