1 /*
2 * Copyright (C) 2004-2012, 2014, 2016 Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (C) 1999-2002 Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and/or distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15 * PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 /* $Id$ */
19
20 #include <config.h>
21
22 #include <isc/mem.h>
23 #include <isc/string.h> /* Required for HP/UX (and others?) */
24 #include <isc/util.h>
25
26 #include <isccfg/namedconf.h>
27 #include <isccfg/aclconf.h>
28
29 #include <dns/acl.h>
30 #include <dns/iptable.h>
31 #include <dns/fixedname.h>
32 #include <dns/log.h>
33
34 #define LOOP_MAGIC ISC_MAGIC('L','O','O','P')
35
36 isc_result_t
cfg_aclconfctx_create(isc_mem_t * mctx,cfg_aclconfctx_t ** ret)37 cfg_aclconfctx_create(isc_mem_t *mctx, cfg_aclconfctx_t **ret) {
38 isc_result_t result;
39 cfg_aclconfctx_t *actx;
40
41 REQUIRE(mctx != NULL);
42 REQUIRE(ret != NULL && *ret == NULL);
43
44 actx = isc_mem_get(mctx, sizeof(*actx));
45 if (actx == NULL)
46 return (ISC_R_NOMEMORY);
47
48 result = isc_refcount_init(&actx->references, 1);
49 if (result != ISC_R_SUCCESS)
50 goto cleanup;
51
52 actx->mctx = NULL;
53 isc_mem_attach(mctx, &actx->mctx);
54 ISC_LIST_INIT(actx->named_acl_cache);
55
56 *ret = actx;
57 return (ISC_R_SUCCESS);
58
59 cleanup:
60 isc_mem_put(mctx, actx, sizeof(*actx));
61 return (result);
62 }
63
64 void
cfg_aclconfctx_attach(cfg_aclconfctx_t * src,cfg_aclconfctx_t ** dest)65 cfg_aclconfctx_attach(cfg_aclconfctx_t *src, cfg_aclconfctx_t **dest) {
66 REQUIRE(src != NULL);
67 REQUIRE(dest != NULL && *dest == NULL);
68
69 isc_refcount_increment(&src->references, NULL);
70 *dest = src;
71 }
72
73 void
cfg_aclconfctx_detach(cfg_aclconfctx_t ** actxp)74 cfg_aclconfctx_detach(cfg_aclconfctx_t **actxp) {
75 cfg_aclconfctx_t *actx;
76 dns_acl_t *dacl, *next;
77 unsigned int refs;
78
79 REQUIRE(actxp != NULL && *actxp != NULL);
80
81 actx = *actxp;
82
83 isc_refcount_decrement(&actx->references, &refs);
84 if (refs == 0) {
85 for (dacl = ISC_LIST_HEAD(actx->named_acl_cache);
86 dacl != NULL;
87 dacl = next)
88 {
89 next = ISC_LIST_NEXT(dacl, nextincache);
90 ISC_LIST_UNLINK(actx->named_acl_cache, dacl,
91 nextincache);
92 dns_acl_detach(&dacl);
93 }
94 isc_mem_putanddetach(&actx->mctx, actx, sizeof(*actx));
95 }
96
97 *actxp = NULL;
98 }
99
100 /*
101 * Find the definition of the named acl whose name is "name".
102 */
103 static isc_result_t
get_acl_def(const cfg_obj_t * cctx,const char * name,const cfg_obj_t ** ret)104 get_acl_def(const cfg_obj_t *cctx, const char *name, const cfg_obj_t **ret) {
105 isc_result_t result;
106 const cfg_obj_t *acls = NULL;
107 const cfg_listelt_t *elt;
108
109 result = cfg_map_get(cctx, "acl", &acls);
110 if (result != ISC_R_SUCCESS)
111 return (result);
112 for (elt = cfg_list_first(acls);
113 elt != NULL;
114 elt = cfg_list_next(elt)) {
115 const cfg_obj_t *acl = cfg_listelt_value(elt);
116 const char *aclname = cfg_obj_asstring(cfg_tuple_get(acl, "name"));
117 if (strcasecmp(aclname, name) == 0) {
118 if (ret != NULL) {
119 *ret = cfg_tuple_get(acl, "value");
120 }
121 return (ISC_R_SUCCESS);
122 }
123 }
124 return (ISC_R_NOTFOUND);
125 }
126
127 static isc_result_t
convert_named_acl(const cfg_obj_t * nameobj,const cfg_obj_t * cctx,isc_log_t * lctx,cfg_aclconfctx_t * ctx,isc_mem_t * mctx,unsigned int nest_level,dns_acl_t ** target)128 convert_named_acl(const cfg_obj_t *nameobj, const cfg_obj_t *cctx,
129 isc_log_t *lctx, cfg_aclconfctx_t *ctx,
130 isc_mem_t *mctx, unsigned int nest_level,
131 dns_acl_t **target)
132 {
133 isc_result_t result;
134 const cfg_obj_t *cacl = NULL;
135 dns_acl_t *dacl;
136 dns_acl_t loop;
137 const char *aclname = cfg_obj_asstring(nameobj);
138
139 /* Look for an already-converted version. */
140 for (dacl = ISC_LIST_HEAD(ctx->named_acl_cache);
141 dacl != NULL;
142 dacl = ISC_LIST_NEXT(dacl, nextincache))
143 {
144 if (strcasecmp(aclname, dacl->name) == 0) {
145 if (ISC_MAGIC_VALID(dacl, LOOP_MAGIC)) {
146 cfg_obj_log(nameobj, lctx, ISC_LOG_ERROR,
147 "acl loop detected: %s", aclname);
148 return (ISC_R_FAILURE);
149 }
150 dns_acl_attach(dacl, target);
151 return (ISC_R_SUCCESS);
152 }
153 }
154 /* Not yet converted. Convert now. */
155 result = get_acl_def(cctx, aclname, &cacl);
156 if (result != ISC_R_SUCCESS) {
157 cfg_obj_log(nameobj, lctx, ISC_LOG_WARNING,
158 "undefined ACL '%s'", aclname);
159 return (result);
160 }
161 /*
162 * Add a loop detection element.
163 */
164 memset(&loop, 0, sizeof(loop));
165 ISC_LINK_INIT(&loop, nextincache);
166 DE_CONST(aclname, loop.name);
167 loop.magic = LOOP_MAGIC;
168 ISC_LIST_APPEND(ctx->named_acl_cache, &loop, nextincache);
169 result = cfg_acl_fromconfig(cacl, cctx, lctx, ctx, mctx,
170 nest_level, &dacl);
171 ISC_LIST_UNLINK(ctx->named_acl_cache, &loop, nextincache);
172 loop.magic = 0;
173 loop.name = NULL;
174 if (result != ISC_R_SUCCESS)
175 return (result);
176 dacl->name = isc_mem_strdup(dacl->mctx, aclname);
177 if (dacl->name == NULL)
178 return (ISC_R_NOMEMORY);
179 ISC_LIST_APPEND(ctx->named_acl_cache, dacl, nextincache);
180 dns_acl_attach(dacl, target);
181 return (ISC_R_SUCCESS);
182 }
183
184 static isc_result_t
convert_keyname(const cfg_obj_t * keyobj,isc_log_t * lctx,isc_mem_t * mctx,dns_name_t * dnsname)185 convert_keyname(const cfg_obj_t *keyobj, isc_log_t *lctx, isc_mem_t *mctx,
186 dns_name_t *dnsname)
187 {
188 isc_result_t result;
189 isc_buffer_t buf;
190 dns_fixedname_t fixname;
191 unsigned int keylen;
192 const char *txtname = cfg_obj_asstring(keyobj);
193
194 keylen = strlen(txtname);
195 isc_buffer_constinit(&buf, txtname, keylen);
196 isc_buffer_add(&buf, keylen);
197 dns_fixedname_init(&fixname);
198 result = dns_name_fromtext(dns_fixedname_name(&fixname), &buf,
199 dns_rootname, 0, NULL);
200 if (result != ISC_R_SUCCESS) {
201 cfg_obj_log(keyobj, lctx, ISC_LOG_WARNING,
202 "key name '%s' is not a valid domain name",
203 txtname);
204 return (result);
205 }
206 return (dns_name_dup(dns_fixedname_name(&fixname), mctx, dnsname));
207 }
208
209 /*
210 * Recursively pre-parse an ACL definition to find the total number
211 * of non-IP-prefix elements (localhost, localnets, key) in all nested
212 * ACLs, so that the parent will have enough space allocated for the
213 * elements table after all the nested ACLs have been merged in to the
214 * parent.
215 */
216 static isc_result_t
count_acl_elements(const cfg_obj_t * caml,const cfg_obj_t * cctx,isc_log_t * lctx,cfg_aclconfctx_t * ctx,isc_mem_t * mctx,isc_uint32_t * count,isc_boolean_t * has_negative)217 count_acl_elements(const cfg_obj_t *caml, const cfg_obj_t *cctx,
218 isc_log_t *lctx, cfg_aclconfctx_t *ctx, isc_mem_t *mctx,
219 isc_uint32_t *count, isc_boolean_t *has_negative)
220 {
221 const cfg_listelt_t *elt;
222 isc_result_t result;
223 isc_uint32_t n = 0;
224
225 REQUIRE(count != NULL);
226
227 if (has_negative != NULL)
228 *has_negative = ISC_FALSE;
229
230 for (elt = cfg_list_first(caml);
231 elt != NULL;
232 elt = cfg_list_next(elt)) {
233 const cfg_obj_t *ce = cfg_listelt_value(elt);
234
235 /* negated element; just get the value. */
236 if (cfg_obj_istuple(ce)) {
237 ce = cfg_tuple_get(ce, "value");
238 if (has_negative != NULL)
239 *has_negative = ISC_TRUE;
240 }
241
242 if (cfg_obj_istype(ce, &cfg_type_keyref)) {
243 n++;
244 } else if (cfg_obj_islist(ce)) {
245 isc_boolean_t negative;
246 isc_uint32_t sub;
247 result = count_acl_elements(ce, cctx, lctx, ctx, mctx,
248 &sub, &negative);
249 if (result != ISC_R_SUCCESS)
250 return (result);
251 n += sub;
252 if (negative)
253 n++;
254 } else if (cfg_obj_isstring(ce)) {
255 const char *name = cfg_obj_asstring(ce);
256 if (strcasecmp(name, "localhost") == 0 ||
257 strcasecmp(name, "localnets") == 0 ||
258 strcasecmp(name, "none") == 0)
259 {
260 n++;
261 } else if (strcasecmp(name, "any") != 0) {
262 dns_acl_t *inneracl = NULL;
263 /*
264 * Convert any named acls we reference now if
265 * they have not already been converted.
266 */
267 result = convert_named_acl(ce, cctx, lctx, ctx,
268 mctx, 0, &inneracl);
269 if (result == ISC_R_SUCCESS) {
270 if (inneracl->has_negatives)
271 n++;
272 else
273 n += inneracl->length;
274 dns_acl_detach(&inneracl);
275 } else
276 return (result);
277 }
278 }
279 }
280
281 *count = n;
282 return (ISC_R_SUCCESS);
283 }
284
285 isc_result_t
cfg_acl_fromconfig(const cfg_obj_t * caml,const cfg_obj_t * cctx,isc_log_t * lctx,cfg_aclconfctx_t * ctx,isc_mem_t * mctx,unsigned int nest_level,dns_acl_t ** target)286 cfg_acl_fromconfig(const cfg_obj_t *caml, const cfg_obj_t *cctx,
287 isc_log_t *lctx, cfg_aclconfctx_t *ctx,
288 isc_mem_t *mctx, unsigned int nest_level,
289 dns_acl_t **target)
290 {
291 return (cfg_acl_fromconfig2(caml, cctx, lctx, ctx, mctx,
292 nest_level, 0, target));
293 }
294
295 isc_result_t
cfg_acl_fromconfig2(const cfg_obj_t * caml,const cfg_obj_t * cctx,isc_log_t * lctx,cfg_aclconfctx_t * ctx,isc_mem_t * mctx,unsigned int nest_level,isc_uint16_t family,dns_acl_t ** target)296 cfg_acl_fromconfig2(const cfg_obj_t *caml, const cfg_obj_t *cctx,
297 isc_log_t *lctx, cfg_aclconfctx_t *ctx,
298 isc_mem_t *mctx, unsigned int nest_level,
299 isc_uint16_t family, dns_acl_t **target)
300 {
301 isc_result_t result;
302 dns_acl_t *dacl = NULL, *inneracl = NULL;
303 dns_aclelement_t *de;
304 const cfg_listelt_t *elt;
305 dns_iptable_t *iptab;
306 int new_nest_level = 0;
307
308 if (nest_level != 0)
309 new_nest_level = nest_level - 1;
310
311 REQUIRE(target != NULL);
312 REQUIRE(*target == NULL || DNS_ACL_VALID(*target));
313
314 if (*target != NULL) {
315 /*
316 * If target already points to an ACL, then we're being
317 * called recursively to configure a nested ACL. The
318 * nested ACL's contents should just be absorbed into its
319 * parent ACL.
320 */
321 dns_acl_attach(*target, &dacl);
322 dns_acl_detach(target);
323 } else {
324 /*
325 * Need to allocate a new ACL structure. Count the items
326 * in the ACL definition that will require space in the
327 * elements table. (Note that if nest_level is nonzero,
328 * *everything* goes in the elements table.)
329 */
330 isc_uint32_t nelem;
331
332 if (nest_level == 0) {
333 result = count_acl_elements(caml, cctx, lctx, ctx,
334 mctx, &nelem, NULL);
335 if (result != ISC_R_SUCCESS)
336 return (result);
337 } else
338 nelem = cfg_list_length(caml, ISC_FALSE);
339
340 result = dns_acl_create(mctx, nelem, &dacl);
341 if (result != ISC_R_SUCCESS)
342 return (result);
343 }
344
345 de = dacl->elements;
346 for (elt = cfg_list_first(caml);
347 elt != NULL;
348 elt = cfg_list_next(elt)) {
349 const cfg_obj_t *ce = cfg_listelt_value(elt);
350 isc_boolean_t neg;
351
352 INSIST(dacl->length <= dacl->alloc);
353
354 if (cfg_obj_istuple(ce)) {
355 /* This must be a negated element. */
356 ce = cfg_tuple_get(ce, "value");
357 neg = ISC_TRUE;
358 dacl->has_negatives = ISC_TRUE;
359 } else
360 neg = ISC_FALSE;
361
362 /*
363 * If nest_level is nonzero, then every element is
364 * to be stored as a separate, nested ACL rather than
365 * merged into the main iptable.
366 */
367 iptab = dacl->iptable;
368
369 if (nest_level != 0) {
370 result = dns_acl_create(mctx,
371 cfg_list_length(ce, ISC_FALSE),
372 &de->nestedacl);
373 if (result != ISC_R_SUCCESS)
374 goto cleanup;
375 iptab = de->nestedacl->iptable;
376 }
377
378 if (cfg_obj_isnetprefix(ce)) {
379 /* Network prefix */
380 isc_netaddr_t addr;
381 unsigned int bitlen;
382
383 cfg_obj_asnetprefix(ce, &addr, &bitlen);
384 if (family != 0 && family != addr.family) {
385 char buf[ISC_NETADDR_FORMATSIZE + 1];
386 isc_netaddr_format(&addr, buf, sizeof(buf));
387 cfg_obj_log(ce, lctx, ISC_LOG_WARNING,
388 "'%s': incorrect address family; "
389 "ignoring", buf);
390 if (nest_level != 0)
391 dns_acl_detach(&de->nestedacl);
392 continue;
393 }
394
395 /*
396 * If nesting ACLs (nest_level != 0), we negate
397 * the nestedacl element, not the iptable entry.
398 */
399 result = dns_iptable_addprefix(iptab, &addr, bitlen,
400 ISC_TF(nest_level != 0 || !neg));
401 if (result != ISC_R_SUCCESS)
402 goto cleanup;
403
404 if (nest_level > 0) {
405 INSIST(dacl->length < dacl->alloc);
406 de->type = dns_aclelementtype_nestedacl;
407 de->negative = neg;
408 } else
409 continue;
410 } else if (cfg_obj_islist(ce)) {
411 /*
412 * If we're nesting ACLs, put the nested
413 * ACL onto the elements list; otherwise
414 * merge it into *this* ACL. We nest ACLs
415 * in two cases: 1) sortlist, 2) if the
416 * nested ACL contains negated members.
417 */
418 if (inneracl != NULL)
419 dns_acl_detach(&inneracl);
420 result = cfg_acl_fromconfig(ce, cctx, lctx,
421 ctx, mctx, new_nest_level,
422 &inneracl);
423 if (result != ISC_R_SUCCESS)
424 goto cleanup;
425 nested_acl:
426 if (nest_level > 0 || inneracl->has_negatives) {
427 INSIST(dacl->length < dacl->alloc);
428 de->type = dns_aclelementtype_nestedacl;
429 de->negative = neg;
430 if (de->nestedacl != NULL)
431 dns_acl_detach(&de->nestedacl);
432 dns_acl_attach(inneracl,
433 &de->nestedacl);
434 dns_acl_detach(&inneracl);
435 /* Fall through. */
436 } else {
437 INSIST(dacl->length + inneracl->length
438 <= dacl->alloc);
439 dns_acl_merge(dacl, inneracl,
440 ISC_TF(!neg));
441 de += inneracl->length; /* elements added */
442 dns_acl_detach(&inneracl);
443 INSIST(dacl->length <= dacl->alloc);
444 continue;
445 }
446 } else if (cfg_obj_istype(ce, &cfg_type_keyref)) {
447 /* Key name. */
448 INSIST(dacl->length < dacl->alloc);
449 de->type = dns_aclelementtype_keyname;
450 de->negative = neg;
451 dns_name_init(&de->keyname, NULL);
452 result = convert_keyname(ce, lctx, mctx,
453 &de->keyname);
454 if (result != ISC_R_SUCCESS)
455 goto cleanup;
456 } else if (cfg_obj_isstring(ce)) {
457 /* ACL name. */
458 const char *name = cfg_obj_asstring(ce);
459 if (strcasecmp(name, "any") == 0) {
460 /* Iptable entry with zero bit length. */
461 result = dns_iptable_addprefix(iptab, NULL, 0,
462 ISC_TF(nest_level != 0 || !neg));
463 if (result != ISC_R_SUCCESS)
464 goto cleanup;
465
466 if (nest_level != 0) {
467 INSIST(dacl->length < dacl->alloc);
468 de->type = dns_aclelementtype_nestedacl;
469 de->negative = neg;
470 } else
471 continue;
472 } else if (strcasecmp(name, "none") == 0) {
473 /* none == !any */
474 /*
475 * We don't unconditional set
476 * dacl->has_negatives and
477 * de->negative to true so we can handle
478 * "!none;".
479 */
480 result = dns_iptable_addprefix(iptab, NULL, 0,
481 ISC_TF(nest_level != 0 || neg));
482 if (result != ISC_R_SUCCESS)
483 goto cleanup;
484
485 if (!neg)
486 dacl->has_negatives = !neg;
487
488 if (nest_level != 0) {
489 INSIST(dacl->length < dacl->alloc);
490 de->type = dns_aclelementtype_nestedacl;
491 de->negative = !neg;
492 } else
493 continue;
494 } else if (strcasecmp(name, "localhost") == 0) {
495 INSIST(dacl->length < dacl->alloc);
496 de->type = dns_aclelementtype_localhost;
497 de->negative = neg;
498 } else if (strcasecmp(name, "localnets") == 0) {
499 INSIST(dacl->length < dacl->alloc);
500 de->type = dns_aclelementtype_localnets;
501 de->negative = neg;
502 } else {
503 if (inneracl != NULL)
504 dns_acl_detach(&inneracl);
505 /*
506 * This call should just find the cached
507 * of the named acl.
508 */
509 result = convert_named_acl(ce, cctx, lctx, ctx,
510 mctx, new_nest_level,
511 &inneracl);
512 if (result != ISC_R_SUCCESS)
513 goto cleanup;
514
515 goto nested_acl;
516 }
517 } else {
518 cfg_obj_log(ce, lctx, ISC_LOG_WARNING,
519 "address match list contains "
520 "unsupported element type");
521 result = ISC_R_FAILURE;
522 goto cleanup;
523 }
524
525 /*
526 * This should only be reached for localhost, localnets
527 * and keyname elements, and nested ACLs if nest_level is
528 * nonzero (i.e., in sortlists).
529 */
530 if (de->nestedacl != NULL &&
531 de->type != dns_aclelementtype_nestedacl)
532 dns_acl_detach(&de->nestedacl);
533
534 dacl->node_count++;
535 de->node_num = dacl->node_count;
536
537 dacl->length++;
538 de++;
539 INSIST(dacl->length <= dacl->alloc);
540 }
541
542 dns_acl_attach(dacl, target);
543 result = ISC_R_SUCCESS;
544
545 cleanup:
546 if (inneracl != NULL)
547 dns_acl_detach(&inneracl);
548 dns_acl_detach(&dacl);
549 return (result);
550 }
551