contrib/bind-9.5.2/lib/isccfg/aclconf.c

   1 /*
   2  * Copyright (C) 2004-2009  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: aclconf.c,v 1.17.2.7 2009/01/19 23:47:03 tbox Exp $ */
  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 void
  37 cfg_aclconfctx_init(cfg_aclconfctx_t *ctx) {
  38         ISC_LIST_INIT(ctx->named_acl_cache);
  39 }
  40
  41 void
  42 cfg_aclconfctx_destroy(cfg_aclconfctx_t *ctx) {
  43         dns_acl_t *dacl, *next;
  44
  45         for (dacl = ISC_LIST_HEAD(ctx->named_acl_cache);
  46              dacl != NULL;
  47              dacl = next)
  48         {
  49                 next = ISC_LIST_NEXT(dacl, nextincache);
  50                 dns_acl_detach(&dacl);
  51         }
  52 }
  53
  54 /*
  55  * Find the definition of the named acl whose name is "name".
  56  */
  57 static isc_result_t
  58 get_acl_def(const cfg_obj_t *cctx, const char *name, const cfg_obj_t **ret) {
  59         isc_result_t result;
  60         const cfg_obj_t *acls = NULL;
  61         const cfg_listelt_t *elt;
  62
  63         result = cfg_map_get(cctx, "acl", &acls);
  64         if (result != ISC_R_SUCCESS)
  65                 return (result);
  66         for (elt = cfg_list_first(acls);
  67              elt != NULL;
  68              elt = cfg_list_next(elt)) {
  69                 const cfg_obj_t *acl = cfg_listelt_value(elt);
  70                 const char *aclname = cfg_obj_asstring(cfg_tuple_get(acl, "name"));
  71                 if (strcasecmp(aclname, name) == 0) {
  72                         if (ret != NULL) {
  73                                 *ret = cfg_tuple_get(acl, "value");
  74                         }
  75                         return (ISC_R_SUCCESS);
  76                 }
  77         }
  78         return (ISC_R_NOTFOUND);
  79 }
  80
  81 static isc_result_t
  82 convert_named_acl(const cfg_obj_t *nameobj, const cfg_obj_t *cctx,
  83                   isc_log_t *lctx, cfg_aclconfctx_t *ctx,
  84                   isc_mem_t *mctx, unsigned int nest_level,
  85                   dns_acl_t **target)
  86 {
  87         isc_result_t result;
  88         const cfg_obj_t *cacl = NULL;
  89         dns_acl_t *dacl;
  90         dns_acl_t loop;
  91         const char *aclname = cfg_obj_asstring(nameobj);
  92
  93         /* Look for an already-converted version. */
  94         for (dacl = ISC_LIST_HEAD(ctx->named_acl_cache);
  95              dacl != NULL;
  96              dacl = ISC_LIST_NEXT(dacl, nextincache))
  97         {
  98                 if (strcasecmp(aclname, dacl->name) == 0) {
  99                         if (ISC_MAGIC_VALID(dacl, LOOP_MAGIC)) {
 100                                 cfg_obj_log(nameobj, lctx, ISC_LOG_ERROR,
 101                                             "acl loop detected: %s", aclname);
 102                                 return (ISC_R_FAILURE);
 103                         }
 104                         dns_acl_attach(dacl, target);
 105                         return (ISC_R_SUCCESS);
 106                 }
 107         }
 108         /* Not yet converted.  Convert now. */
 109         result = get_acl_def(cctx, aclname, &cacl);
 110         if (result != ISC_R_SUCCESS) {
 111                 cfg_obj_log(nameobj, lctx, ISC_LOG_WARNING,
 112                             "undefined ACL '%s'", aclname);
 113                 return (result);
 114         }
 115         /*
 116          * Add a loop detection element.
 117          */
 118         memset(&loop, 0, sizeof(loop));
 119         ISC_LINK_INIT(&loop, nextincache);
 120         DE_CONST(aclname, loop.name);
 121         loop.magic = LOOP_MAGIC;
 122         ISC_LIST_APPEND(ctx->named_acl_cache, &loop, nextincache);
 123         result = cfg_acl_fromconfig(cacl, cctx, lctx, ctx, mctx,
 124                                     nest_level, &dacl);
 125         ISC_LIST_UNLINK(ctx->named_acl_cache, &loop, nextincache);
 126         loop.magic = 0;
 127         loop.name = NULL;
 128         if (result != ISC_R_SUCCESS)
 129                 return (result);
 130         dacl->name = isc_mem_strdup(dacl->mctx, aclname);
 131         if (dacl->name == NULL)
 132                 return (ISC_R_NOMEMORY);
 133         ISC_LIST_APPEND(ctx->named_acl_cache, dacl, nextincache);
 134         dns_acl_attach(dacl, target);
 135         return (ISC_R_SUCCESS);
 136 }
 137
 138 static isc_result_t
 139 convert_keyname(const cfg_obj_t *keyobj, isc_log_t *lctx, isc_mem_t *mctx,
 140                 dns_name_t *dnsname)
 141 {
 142         isc_result_t result;
 143         isc_buffer_t buf;
 144         dns_fixedname_t fixname;
 145         unsigned int keylen;
 146         const char *txtname = cfg_obj_asstring(keyobj);
 147
 148         keylen = strlen(txtname);
 149         isc_buffer_init(&buf, txtname, keylen);
 150         isc_buffer_add(&buf, keylen);
 151         dns_fixedname_init(&fixname);
 152         result = dns_name_fromtext(dns_fixedname_name(&fixname), &buf,
 153                                    dns_rootname, ISC_FALSE, NULL);
 154         if (result != ISC_R_SUCCESS) {
 155                 cfg_obj_log(keyobj, lctx, ISC_LOG_WARNING,
 156                             "key name '%s' is not a valid domain name",
 157                             txtname);
 158                 return (result);
 159         }
 160         return (dns_name_dup(dns_fixedname_name(&fixname), mctx, dnsname));
 161 }
 162
 163 /*
 164  * Recursively pre-parse an ACL definition to find the total number
 165  * of non-IP-prefix elements (localhost, localnets, key) in all nested
 166  * ACLs, so that the parent will have enough space allocated for the
 167  * elements table after all the nested ACLs have been merged in to the
 168  * parent.
 169  */
 170 static int
 171 count_acl_elements(const cfg_obj_t *caml, const cfg_obj_t *cctx)
 172 {
 173         const cfg_listelt_t *elt;
 174         const cfg_obj_t *cacl = NULL;
 175         isc_result_t result;
 176         int n = 0;
 177
 178         for (elt = cfg_list_first(caml);
 179              elt != NULL;
 180              elt = cfg_list_next(elt)) {
 181                 const cfg_obj_t *ce = cfg_listelt_value(elt);
 182
 183                 /* negated element; just get the value. */
 184                 if (cfg_obj_istuple(ce))
 185                         ce = cfg_tuple_get(ce, "value");
 186
 187                 if (cfg_obj_istype(ce, &cfg_type_keyref)) {
 188                         n++;
 189                 } else if (cfg_obj_islist(ce)) {
 190                         n += count_acl_elements(ce, cctx);
 191                 } else if (cfg_obj_isstring(ce)) {
 192                         const char *name = cfg_obj_asstring(ce);
 193                         if (strcasecmp(name, "localhost") == 0 ||
 194                             strcasecmp(name, "localnets") == 0) {
 195                                 n++;
 196                         } else if (strcasecmp(name, "any") != 0 &&
 197                                    strcasecmp(name, "none") != 0) {
 198                                 result = get_acl_def(cctx, name, &cacl);
 199                                 if (result == ISC_R_SUCCESS)
 200                                         n += count_acl_elements(cacl, cctx) + 1;
 201                         }
 202                 }
 203         }
 204
 205         return n;
 206 }
 207
 208 isc_result_t
 209 cfg_acl_fromconfig(const cfg_obj_t *caml,
 210                    const cfg_obj_t *cctx,
 211                    isc_log_t *lctx,
 212                    cfg_aclconfctx_t *ctx,
 213                    isc_mem_t *mctx,
 214                    unsigned int nest_level,
 215                    dns_acl_t **target)
 216 {
 217         isc_result_t result;
 218         dns_acl_t *dacl = NULL, *inneracl = NULL;
 219         dns_aclelement_t *de;
 220         const cfg_listelt_t *elt;
 221         dns_iptable_t *iptab;
 222         int new_nest_level = 0;
 223
 224         if (nest_level != 0)
 225                 new_nest_level = nest_level - 1;
 226
 227         REQUIRE(target != NULL);
 228         REQUIRE(*target == NULL || DNS_ACL_VALID(*target));
 229
 230         if (*target != NULL) {
 231                 /*
 232                  * If target already points to an ACL, then we're being
 233                  * called recursively to configure a nested ACL.  The
 234                  * nested ACL's contents should just be absorbed into its
 235                  * parent ACL.
 236                  */
 237                 dns_acl_attach(*target, &dacl);
 238                 dns_acl_detach(target);
 239         } else {
 240                 /*
 241                  * Need to allocate a new ACL structure.  Count the items
 242                  * in the ACL definition that will require space in the
 243                  * elements table.  (Note that if nest_level is nonzero,
 244                  * *everything* goes in the elements table.)
 245                  */
 246                 int nelem;
 247
 248                 if (nest_level == 0)
 249                         nelem = count_acl_elements(caml, cctx);
 250                 else
 251                         nelem = cfg_list_length(caml, ISC_FALSE);
 252
 253                 result = dns_acl_create(mctx, nelem, &dacl);
 254                 if (result != ISC_R_SUCCESS)
 255                         return (result);
 256         }
 257
 258         de = dacl->elements;
 259         for (elt = cfg_list_first(caml);
 260              elt != NULL;
 261              elt = cfg_list_next(elt)) {
 262                 const cfg_obj_t *ce = cfg_listelt_value(elt);
 263                 isc_boolean_t   neg;
 264
 265                 if (cfg_obj_istuple(ce)) {
 266                         /* This must be a negated element. */
 267                         ce = cfg_tuple_get(ce, "value");
 268                         neg = ISC_TRUE;
 269                         dacl->has_negatives = ISC_TRUE;
 270                 } else
 271                         neg = ISC_FALSE;
 272
 273                 /*
 274                  * If nest_level is nonzero, then every element is
 275                  * to be stored as a separate, nested ACL rather than
 276                  * merged into the main iptable.
 277                  */
 278                 iptab = dacl->iptable;
 279
 280                 if (nest_level != 0) {
 281                         result = dns_acl_create(mctx,
 282                                                 cfg_list_length(ce, ISC_FALSE),
 283                                                 &de->nestedacl);
 284                         if (result != ISC_R_SUCCESS)
 285                                 goto cleanup;
 286                         iptab = de->nestedacl->iptable;
 287                 }
 288
 289                 if (cfg_obj_isnetprefix(ce)) {
 290                         /* Network prefix */
 291                         isc_netaddr_t   addr;
 292                         unsigned int    bitlen;
 293
 294                         cfg_obj_asnetprefix(ce, &addr, &bitlen);
 295
 296                         /*
 297                          * If nesting ACLs (nest_level != 0), we negate
 298                          * the nestedacl element, not the iptable entry.
 299                          */
 300                         result = dns_iptable_addprefix(iptab, &addr, bitlen,
 301                                               ISC_TF(nest_level != 0 || !neg));
 302                         if (result != ISC_R_SUCCESS)
 303                                 goto cleanup;
 304
 305                         if (nest_level > 0) {
 306                                 de->type = dns_aclelementtype_nestedacl;
 307                                 de->negative = neg;
 308                         } else
 309                                 continue;
 310                 } else if (cfg_obj_islist(ce)) {
 311                         /*
 312                          * If we're nesting ACLs, put the nested
 313                          * ACL onto the elements list; otherwise
 314                          * merge it into *this* ACL.  We nest ACLs
 315                          * in two cases: 1) sortlist, 2) if the
 316                          * nested ACL contains negated members.
 317                          */
 318                         if (inneracl != NULL)
 319                                 dns_acl_detach(&inneracl);
 320                         result = cfg_acl_fromconfig(ce, cctx, lctx,
 321                                                     ctx, mctx, new_nest_level,
 322                                                     &inneracl);
 323                         if (result != ISC_R_SUCCESS)
 324                                 goto cleanup;
 325 nested_acl:
 326                         if (nest_level > 0 || inneracl->has_negatives) {
 327                                 de->type = dns_aclelementtype_nestedacl;
 328                                 de->negative = neg;
 329                                 if (de->nestedacl != NULL)
 330                                         dns_acl_detach(&de->nestedacl);
 331                                 dns_acl_attach(inneracl,
 332                                                &de->nestedacl);
 333                                 dns_acl_detach(&inneracl);
 334                                 /* Fall through. */
 335                         } else {
 336                                 dns_acl_merge(dacl, inneracl,
 337                                               ISC_TF(!neg));
 338                                 de += inneracl->length;  /* elements added */
 339                                 dns_acl_detach(&inneracl);
 340                                 continue;
 341                         }
 342                 } else if (cfg_obj_istype(ce, &cfg_type_keyref)) {
 343                         /* Key name. */
 344                         de->type = dns_aclelementtype_keyname;
 345                         de->negative = neg;
 346                         dns_name_init(&de->keyname, NULL);
 347                         result = convert_keyname(ce, lctx, mctx,
 348                                                  &de->keyname);
 349                         if (result != ISC_R_SUCCESS)
 350                                 goto cleanup;
 351                 } else if (cfg_obj_isstring(ce)) {
 352                         /* ACL name. */
 353                         const char *name = cfg_obj_asstring(ce);
 354                         if (strcasecmp(name, "any") == 0) {
 355                                 /* Iptable entry with zero bit length. */
 356                                 result = dns_iptable_addprefix(iptab, NULL, 0,
 357                                               ISC_TF(nest_level != 0 || !neg));
 358                                 if (result != ISC_R_SUCCESS)
 359                                         goto cleanup;
 360
 361                                 if (nest_level != 0) {
 362                                         de->type = dns_aclelementtype_nestedacl;
 363                                         de->negative = neg;
 364                                 } else
 365                                         continue;
 366                         } else if (strcasecmp(name, "none") == 0) {
 367                                 /* none == !any */
 368                                 /*
 369                                  * We don't unconditional set
 370                                  * dacl->has_negatives and
 371                                  * de->negative to true so we can handle
 372                                  * "!none;".
 373                                  */
 374                                 result = dns_iptable_addprefix(iptab, NULL, 0,
 375                                               ISC_TF(nest_level != 0 || neg));
 376                                 if (result != ISC_R_SUCCESS)
 377                                         goto cleanup;
 378
 379                                 if (!neg)
 380                                         dacl->has_negatives = !neg;
 381
 382                                 if (nest_level != 0) {
 383                                         de->type = dns_aclelementtype_nestedacl;
 384                                         de->negative = !neg;
 385                                 } else
 386                                         continue;
 387                         } else if (strcasecmp(name, "localhost") == 0) {
 388                                 de->type = dns_aclelementtype_localhost;
 389                                 de->negative = neg;
 390                         } else if (strcasecmp(name, "localnets") == 0) {
 391                                 de->type = dns_aclelementtype_localnets;
 392                                 de->negative = neg;
 393                         } else {
 394                                 if (inneracl != NULL)
 395                                         dns_acl_detach(&inneracl);
 396                                 result = convert_named_acl(ce, cctx, lctx, ctx,
 397                                                            mctx, new_nest_level,
 398                                                            &inneracl);
 399                                 if (result != ISC_R_SUCCESS)
 400                                         goto cleanup;
 401
 402                                 goto nested_acl;
 403                         }
 404                 } else {
 405                         cfg_obj_log(ce, lctx, ISC_LOG_WARNING,
 406                                     "address match list contains "
 407                                     "unsupported element type");
 408                         result = ISC_R_FAILURE;
 409                         goto cleanup;
 410                 }
 411
 412                 /*
 413                  * This should only be reached for localhost, localnets
 414                  * and keyname elements, and nested ACLs if nest_level is
 415                  * nonzero (i.e., in sortlists).
 416                  */
 417                 if (de->nestedacl != NULL &&
 418                     de->type != dns_aclelementtype_nestedacl)
 419                         dns_acl_detach(&de->nestedacl);
 420
 421                 dacl->node_count++;
 422                 de->node_num = dacl->node_count;
 423
 424                 dacl->length++;
 425                 de++;
 426                 INSIST(dacl->length <= dacl->alloc);
 427         }
 428
 429         dns_acl_attach(dacl, target);
 430         result = ISC_R_SUCCESS;
 431
 432  cleanup:
 433         if (inneracl != NULL)
 434                 dns_acl_detach(&inneracl);
 435         dns_acl_detach(&dacl);
 436         return (result);
 437 }