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 #include "iterator/iter_fwd.h"
57 #include "iterator/iter_hints.h"
58
59 int
context_finalize(struct ub_ctx * ctx)60 context_finalize(struct ub_ctx* ctx)
61 {
62 int is_rpz = 0;
63 struct config_file* cfg = ctx->env->cfg;
64 verbosity = cfg->verbosity;
65 if(ctx_logfile_overridden && !ctx->logfile_override) {
66 log_file(NULL); /* clear that override */
67 ctx_logfile_overridden = 0;
68 }
69 if(ctx->logfile_override) {
70 ctx_logfile_overridden = 1;
71 log_file(ctx->log_out);
72 } else {
73 log_init(cfg->logfile, cfg->use_syslog, NULL);
74 }
75 ctx->pipe_pid = getpid();
76 cfg_apply_local_port_policy(cfg, 65536);
77 config_apply(cfg);
78 if(!modstack_setup(&ctx->mods, cfg->module_conf, ctx->env))
79 return UB_INITFAIL;
80 listen_setup_locks();
81 log_edns_known_options(VERB_ALGO, ctx->env);
82 ctx->local_zones = local_zones_create();
83 if(!ctx->local_zones)
84 return UB_NOMEM;
85 if(!local_zones_apply_cfg(ctx->local_zones, cfg))
86 return UB_INITFAIL;
87 if(!auth_zones_apply_cfg(ctx->env->auth_zones, cfg, 1, &is_rpz,
88 ctx->env, &ctx->mods))
89 return UB_INITFAIL;
90 if(!(ctx->env->fwds = forwards_create()) ||
91 !forwards_apply_cfg(ctx->env->fwds, cfg))
92 return UB_INITFAIL;
93 if(!(ctx->env->hints = hints_create()) ||
94 !hints_apply_cfg(ctx->env->hints, cfg))
95 return UB_INITFAIL;
96 if(!edns_strings_apply_cfg(ctx->env->edns_strings, cfg))
97 return UB_INITFAIL;
98 if(!slabhash_is_size(ctx->env->msg_cache, cfg->msg_cache_size,
99 cfg->msg_cache_slabs)) {
100 slabhash_delete(ctx->env->msg_cache);
101 ctx->env->msg_cache = slabhash_create(cfg->msg_cache_slabs,
102 HASH_DEFAULT_STARTARRAY, cfg->msg_cache_size,
103 msgreply_sizefunc, query_info_compare,
104 query_entry_delete, reply_info_delete, NULL);
105 if(!ctx->env->msg_cache)
106 return UB_NOMEM;
107 }
108 ctx->env->rrset_cache = rrset_cache_adjust(ctx->env->rrset_cache,
109 ctx->env->cfg, ctx->env->alloc);
110 if(!ctx->env->rrset_cache)
111 return UB_NOMEM;
112 ctx->env->infra_cache = infra_adjust(ctx->env->infra_cache, cfg);
113 if(!ctx->env->infra_cache)
114 return UB_NOMEM;
115 ctx->finalized = 1;
116 return UB_NOERROR;
117 }
118
context_query_cmp(const void * a,const void * b)119 int context_query_cmp(const void* a, const void* b)
120 {
121 if( *(int*)a < *(int*)b )
122 return -1;
123 if( *(int*)a > *(int*)b )
124 return 1;
125 return 0;
126 }
127
128 void
context_query_delete(struct ctx_query * q)129 context_query_delete(struct ctx_query* q)
130 {
131 if(!q) return;
132 ub_resolve_free(q->res);
133 free(q->msg);
134 free(q);
135 }
136
137 /** How many times to try to find an unused query-id-number for async */
138 #define NUM_ID_TRIES 100000
139 /** find next useful id number of 0 on error */
140 static int
find_id(struct ub_ctx * ctx,int * id)141 find_id(struct ub_ctx* ctx, int* id)
142 {
143 size_t tries = 0;
144 ctx->next_querynum++;
145 while(rbtree_search(&ctx->queries, &ctx->next_querynum)) {
146 ctx->next_querynum++; /* numerical wraparound is fine */
147 if(tries++ > NUM_ID_TRIES)
148 return 0;
149 }
150 *id = ctx->next_querynum;
151 return 1;
152 }
153
154 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)155 context_new(struct ub_ctx* ctx, const char* name, int rrtype, int rrclass,
156 ub_callback_type cb, ub_event_callback_type cb_event, void* cbarg)
157 {
158 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q));
159 if(!q) return NULL;
160 lock_basic_lock(&ctx->cfglock);
161 if(!find_id(ctx, &q->querynum)) {
162 lock_basic_unlock(&ctx->cfglock);
163 free(q);
164 return NULL;
165 }
166 lock_basic_unlock(&ctx->cfglock);
167 q->node.key = &q->querynum;
168 q->async = (cb != NULL || cb_event != NULL);
169 q->cb = cb;
170 q->cb_event = cb_event;
171 q->cb_arg = cbarg;
172 q->res = (struct ub_result*)calloc(1, sizeof(*q->res));
173 if(!q->res) {
174 free(q);
175 return NULL;
176 }
177 q->res->qname = strdup(name);
178 if(!q->res->qname) {
179 free(q->res);
180 free(q);
181 return NULL;
182 }
183 q->res->qtype = rrtype;
184 q->res->qclass = rrclass;
185
186 /* add to query list */
187 lock_basic_lock(&ctx->cfglock);
188 if(q->async)
189 ctx->num_async ++;
190 (void)rbtree_insert(&ctx->queries, &q->node);
191 lock_basic_unlock(&ctx->cfglock);
192 return q;
193 }
194
195 struct alloc_cache*
context_obtain_alloc(struct ub_ctx * ctx,int locking)196 context_obtain_alloc(struct ub_ctx* ctx, int locking)
197 {
198 struct alloc_cache* a;
199 int tnum = 0;
200 if(locking) {
201 lock_basic_lock(&ctx->cfglock);
202 }
203 a = ctx->alloc_list;
204 if(a)
205 ctx->alloc_list = a->super; /* snip off list */
206 else tnum = ctx->thr_next_num++;
207 if(locking) {
208 lock_basic_unlock(&ctx->cfglock);
209 }
210 if(a) {
211 a->super = &ctx->superalloc;
212 return a;
213 }
214 a = (struct alloc_cache*)calloc(1, sizeof(*a));
215 if(!a)
216 return NULL;
217 alloc_init(a, &ctx->superalloc, tnum);
218 return a;
219 }
220
221 void
context_release_alloc(struct ub_ctx * ctx,struct alloc_cache * alloc,int locking)222 context_release_alloc(struct ub_ctx* ctx, struct alloc_cache* alloc,
223 int locking)
224 {
225 if(!ctx || !alloc)
226 return;
227 if(locking) {
228 lock_basic_lock(&ctx->cfglock);
229 }
230 alloc->super = ctx->alloc_list;
231 ctx->alloc_list = alloc;
232 if(locking) {
233 lock_basic_unlock(&ctx->cfglock);
234 }
235 }
236
237 uint8_t*
context_serialize_new_query(struct ctx_query * q,uint32_t * len)238 context_serialize_new_query(struct ctx_query* q, uint32_t* len)
239 {
240 /* format for new query is
241 * o uint32 cmd
242 * o uint32 id
243 * o uint32 type
244 * o uint32 class
245 * o rest queryname (string)
246 */
247 uint8_t* p;
248 size_t slen = strlen(q->res->qname) + 1/*end of string*/;
249 *len = sizeof(uint32_t)*4 + slen;
250 p = (uint8_t*)malloc(*len);
251 if(!p) return NULL;
252 sldns_write_uint32(p, UB_LIBCMD_NEWQUERY);
253 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
254 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)q->res->qtype);
255 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->res->qclass);
256 memmove(p+4*sizeof(uint32_t), q->res->qname, slen);
257 return p;
258 }
259
260 struct ctx_query*
context_deserialize_new_query(struct ub_ctx * ctx,uint8_t * p,uint32_t len)261 context_deserialize_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len)
262 {
263 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q));
264 if(!q) return NULL;
265 if(len < 4*sizeof(uint32_t)+1) {
266 free(q);
267 return NULL;
268 }
269 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY);
270 q->querynum = (int)sldns_read_uint32(p+sizeof(uint32_t));
271 q->node.key = &q->querynum;
272 q->async = 1;
273 q->res = (struct ub_result*)calloc(1, sizeof(*q->res));
274 if(!q->res) {
275 free(q);
276 return NULL;
277 }
278 q->res->qtype = (int)sldns_read_uint32(p+2*sizeof(uint32_t));
279 q->res->qclass = (int)sldns_read_uint32(p+3*sizeof(uint32_t));
280 q->res->qname = strdup((char*)(p+4*sizeof(uint32_t)));
281 if(!q->res->qname) {
282 free(q->res);
283 free(q);
284 return NULL;
285 }
286
287 /** add to query list */
288 ctx->num_async++;
289 (void)rbtree_insert(&ctx->queries, &q->node);
290 return q;
291 }
292
293 struct ctx_query*
context_lookup_new_query(struct ub_ctx * ctx,uint8_t * p,uint32_t len)294 context_lookup_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len)
295 {
296 struct ctx_query* q;
297 int querynum;
298 if(len < 4*sizeof(uint32_t)+1) {
299 return NULL;
300 }
301 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY);
302 querynum = (int)sldns_read_uint32(p+sizeof(uint32_t));
303 q = (struct ctx_query*)rbtree_search(&ctx->queries, &querynum);
304 if(!q) {
305 return NULL;
306 }
307 log_assert(q->async);
308 return q;
309 }
310
311 uint8_t*
context_serialize_answer(struct ctx_query * q,int err,sldns_buffer * pkt,uint32_t * len)312 context_serialize_answer(struct ctx_query* q, int err, sldns_buffer* pkt,
313 uint32_t* len)
314 {
315 /* answer format
316 * o uint32 cmd
317 * o uint32 id
318 * o uint32 error_code
319 * o uint32 msg_security
320 * o uint32 was_ratelimited
321 * o uint32 length of why_bogus string (+1 for eos); 0 absent.
322 * o why_bogus_string
323 * o the remainder is the answer msg from resolver lookup.
324 * remainder can be length 0.
325 */
326 size_t size_of_uint32s = 6 * sizeof(uint32_t);
327 size_t pkt_len = pkt?sldns_buffer_remaining(pkt):0;
328 size_t wlen = (pkt&&q->res->why_bogus)?strlen(q->res->why_bogus)+1:0;
329 uint8_t* p;
330 *len = size_of_uint32s + pkt_len + wlen;
331 p = (uint8_t*)malloc(*len);
332 if(!p) return NULL;
333 sldns_write_uint32(p, UB_LIBCMD_ANSWER);
334 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
335 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)err);
336 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->msg_security);
337 sldns_write_uint32(p+4*sizeof(uint32_t), (uint32_t)q->res->was_ratelimited);
338 sldns_write_uint32(p+5*sizeof(uint32_t), (uint32_t)wlen);
339 if(wlen > 0)
340 memmove(p+size_of_uint32s, q->res->why_bogus, wlen);
341 if(pkt_len > 0)
342 memmove(p+size_of_uint32s+wlen,
343 sldns_buffer_begin(pkt), pkt_len);
344 return p;
345 }
346
347 struct ctx_query*
context_deserialize_answer(struct ub_ctx * ctx,uint8_t * p,uint32_t len,int * err)348 context_deserialize_answer(struct ub_ctx* ctx,
349 uint8_t* p, uint32_t len, int* err)
350 {
351 size_t size_of_uint32s = 6 * sizeof(uint32_t);
352 struct ctx_query* q = NULL ;
353 int id;
354 size_t wlen;
355 if(len < size_of_uint32s) return NULL;
356 log_assert( sldns_read_uint32(p) == UB_LIBCMD_ANSWER);
357 id = (int)sldns_read_uint32(p+sizeof(uint32_t));
358 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id);
359 if(!q) return NULL;
360 *err = (int)sldns_read_uint32(p+2*sizeof(uint32_t));
361 q->msg_security = sldns_read_uint32(p+3*sizeof(uint32_t));
362 q->res->was_ratelimited = (int)sldns_read_uint32(p+4*sizeof(uint32_t));
363 wlen = (size_t)sldns_read_uint32(p+5*sizeof(uint32_t));
364 if(len > size_of_uint32s && wlen > 0) {
365 if(len >= size_of_uint32s+wlen)
366 q->res->why_bogus = (char*)memdup(
367 p+size_of_uint32s, wlen);
368 if(!q->res->why_bogus) {
369 /* pass malloc failure to the user callback */
370 q->msg_len = 0;
371 *err = UB_NOMEM;
372 return q;
373 }
374 q->res->why_bogus[wlen-1] = 0; /* zero terminated for sure */
375 }
376 if(len > size_of_uint32s+wlen) {
377 q->msg_len = len - size_of_uint32s - wlen;
378 q->msg = (uint8_t*)memdup(p+size_of_uint32s+wlen,
379 q->msg_len);
380 if(!q->msg) {
381 /* pass malloc failure to the user callback */
382 q->msg_len = 0;
383 *err = UB_NOMEM;
384 return q;
385 }
386 }
387 return q;
388 }
389
390 uint8_t*
context_serialize_cancel(struct ctx_query * q,uint32_t * len)391 context_serialize_cancel(struct ctx_query* q, uint32_t* len)
392 {
393 /* format of cancel:
394 * o uint32 cmd
395 * o uint32 async-id */
396 uint8_t* p = (uint8_t*)reallocarray(NULL, sizeof(uint32_t), 2);
397 if(!p) return NULL;
398 *len = 2*sizeof(uint32_t);
399 sldns_write_uint32(p, UB_LIBCMD_CANCEL);
400 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum);
401 return p;
402 }
403
context_deserialize_cancel(struct ub_ctx * ctx,uint8_t * p,uint32_t len)404 struct ctx_query* context_deserialize_cancel(struct ub_ctx* ctx,
405 uint8_t* p, uint32_t len)
406 {
407 struct ctx_query* q;
408 int id;
409 if(len != 2*sizeof(uint32_t)) return NULL;
410 log_assert( sldns_read_uint32(p) == UB_LIBCMD_CANCEL);
411 id = (int)sldns_read_uint32(p+sizeof(uint32_t));
412 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id);
413 return q;
414 }
415
416 uint8_t*
context_serialize_quit(uint32_t * len)417 context_serialize_quit(uint32_t* len)
418 {
419 uint32_t* p = (uint32_t*)malloc(sizeof(uint32_t));
420 if(!p)
421 return NULL;
422 *len = sizeof(uint32_t);
423 sldns_write_uint32(p, UB_LIBCMD_QUIT);
424 return (uint8_t*)p;
425 }
426
context_serial_getcmd(uint8_t * p,uint32_t len)427 enum ub_ctx_cmd context_serial_getcmd(uint8_t* p, uint32_t len)
428 {
429 uint32_t v;
430 if((size_t)len < sizeof(v))
431 return UB_LIBCMD_QUIT;
432 v = sldns_read_uint32(p);
433 return v;
434 }
435