unbound/iterator/iter_delegpt.h

   1 /*
   2  * iterator/iter_delegpt.h - delegation point with NS and address information.
   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 implements the Delegation Point. It contains a list of name servers
  40  * and their addresses if known.
  41  */
  42
  43 #ifndef ITERATOR_ITER_DELEGPT_H
  44 #define ITERATOR_ITER_DELEGPT_H
  45 #include "util/log.h"
  46 struct regional;
  47 struct delegpt_ns;
  48 struct delegpt_addr;
  49 struct dns_msg;
  50 struct ub_packed_rrset_key;
  51 struct msgreply_entry;
  52
  53 /**
  54  * Delegation Point.
  55  * For a domain name, the NS rrset, and the A and AAAA records for those.
  56  */
  57 struct delegpt {
  58         /** the domain name of the delegation point. */
  59         uint8_t* name;
  60         /** length of the delegation point name */
  61         size_t namelen;
  62         /** number of labels in delegation point */
  63         int namelabs;
  64
  65         /** the nameservers, names from the NS RRset rdata. */
  66         struct delegpt_ns* nslist;
  67         /** the target addresses for delegation */
  68         struct delegpt_addr* target_list;
  69         /** the list of usable targets; subset of target_list
  70          * the items in this list are not part of the result list.  */
  71         struct delegpt_addr* usable_list;
  72         /** the list of returned targets; subset of target_list */
  73         struct delegpt_addr* result_list;
  74
  75         /** if true, the NS RRset was bogus. All info is bad. */
  76         int bogus;
  77         /** if true, the parent-side NS record has been applied:
  78          * its names have been added and their addresses can follow later.
  79          * Also true if the delegationpoint was created from a delegation
  80          * message and thus contains the parent-side-info already. */
  81         uint8_t has_parent_side_NS;
  82         /** for assertions on type of delegpt */
  83         uint8_t dp_type_mlc;
  84 };
  85
  86 /**
  87  * Nameservers for a delegation point.
  88  */
  89 struct delegpt_ns {
  90         /** next in list */
  91         struct delegpt_ns* next;
  92         /** name of nameserver */
  93         uint8_t* name;
  94         /** length of name */
  95         size_t namelen;
  96         /**
  97          * If the name has been resolved. false if not queried for yet.
  98          * true if the A, AAAA queries have been generated.
  99          * marked true if those queries fail.
 100          * and marked true if got4 and got6 are both true.
 101          */
 102         int resolved;
 103         /** if the ipv4 address is in the delegpt */
 104         uint8_t got4;
 105         /** if the ipv6 address is in the delegpt */
 106         uint8_t got6;
 107         /**
 108          * If the name is parent-side only and thus dispreferred.
 109          * Its addresses become dispreferred as well
 110          */
 111         uint8_t lame;
 112         /** if the parent-side ipv4 address has been looked up (last resort).
 113          * Also enabled if a parent-side cache entry exists, or a parent-side
 114          * negative-cache entry exists. */
 115         uint8_t done_pside4;
 116         /** if the parent-side ipv6 address has been looked up (last resort).
 117          * Also enabled if a parent-side cache entry exists, or a parent-side
 118          * negative-cache entry exists. */
 119         uint8_t done_pside6;
 120 };
 121
 122 /**
 123  * Address of target nameserver in delegation point.
 124  */
 125 struct delegpt_addr {
 126         /** next delegation point in results */
 127         struct delegpt_addr* next_result;
 128         /** next delegation point in usable list */
 129         struct delegpt_addr* next_usable;
 130         /** next delegation point in all targets list */
 131         struct delegpt_addr* next_target;
 132
 133         /** delegation point address */
 134         struct sockaddr_storage addr;
 135         /** length of addr */
 136         socklen_t addrlen;
 137         /** number of attempts for this addr */
 138         int attempts;
 139         /** rtt stored here in the selection algorithm */
 140         int sel_rtt;
 141         /** if true, the A or AAAA RR was bogus, so this address is bad.
 142          * Also check the dp->bogus to see if everything is bogus. */
 143         uint8_t bogus;
 144         /** if true, this address is dispreferred: it is a lame IP address */
 145         uint8_t lame;
 146         /** if the address is dnsseclame, but this cannot be cached, this
 147          * option is useful to mark the address dnsseclame.
 148          * This value is not copied in addr-copy and dp-copy. */
 149         uint8_t dnsseclame;
 150 };
 151
 152 /**
 153  * Create new delegation point.
 154  * @param regional: where to allocate it.
 155  * @return new delegation point or NULL on error.
 156  */
 157 struct delegpt* delegpt_create(struct regional* regional);
 158
 159 /**
 160  * Create a copy of a delegation point.
 161  * @param dp: delegation point to copy.
 162  * @param regional: where to allocate it.
 163  * @return new delegation point or NULL on error.
 164  */
 165 struct delegpt* delegpt_copy(struct delegpt* dp, struct regional* regional);
 166
 167 /**
 168  * Set name of delegation point.
 169  * @param dp: delegation point.
 170  * @param regional: where to allocate the name copy.
 171  * @param name: name to use.
 172  * @return false on error.
 173  */
 174 int delegpt_set_name(struct delegpt* dp, struct regional* regional,
 175         uint8_t* name);
 176
 177 /**
 178  * Add a name to the delegation point.
 179  * @param dp: delegation point.
 180  * @param regional: where to allocate the info.
 181  * @param name: domain name in wire format.
 182  * @param lame: name is lame, disprefer it.
 183  * @return false on error.
 184  */
 185 int delegpt_add_ns(struct delegpt* dp, struct regional* regional,
 186         uint8_t* name, uint8_t lame);
 187
 188 /**
 189  * Add NS rrset; calls add_ns repeatedly.
 190  * @param dp: delegation point.
 191  * @param regional: where to allocate the info.
 192  * @param ns_rrset: NS rrset.
 193  * @param lame: rrset is lame, disprefer it.
 194  * @return 0 on alloc error.
 195  */
 196 int delegpt_rrset_add_ns(struct delegpt* dp, struct regional* regional,
 197         struct ub_packed_rrset_key* ns_rrset, uint8_t lame);
 198
 199 /**
 200  * Add target address to the delegation point.
 201  * @param dp: delegation point.
 202  * @param regional: where to allocate the info.
 203  * @param name: name for which target was found (must be in nslist).
 204  *      This name is marked resolved.
 205  * @param namelen: length of name.
 206  * @param addr: the address.
 207  * @param addrlen: the length of addr.
 208  * @param bogus: security status for the address, pass true if bogus.
 209  * @param lame: address is lame.
 210  * @return false on error.
 211  */
 212 int delegpt_add_target(struct delegpt* dp, struct regional* regional,
 213         uint8_t* name, size_t namelen, struct sockaddr_storage* addr,
 214         socklen_t addrlen, uint8_t bogus, uint8_t lame);
 215
 216 /**
 217  * Add A RRset to delegpt.
 218  * @param dp: delegation point.
 219  * @param regional: where to allocate the info.
 220  * @param rrset: RRset A to add.
 221  * @param lame: rrset is lame, disprefer it.
 222  * @return 0 on alloc error.
 223  */
 224 int delegpt_add_rrset_A(struct delegpt* dp, struct regional* regional,
 225         struct ub_packed_rrset_key* rrset, uint8_t lame);
 226
 227 /**
 228  * Add AAAA RRset to delegpt.
 229  * @param dp: delegation point.
 230  * @param regional: where to allocate the info.
 231  * @param rrset: RRset AAAA to add.
 232  * @param lame: rrset is lame, disprefer it.
 233  * @return 0 on alloc error.
 234  */
 235 int delegpt_add_rrset_AAAA(struct delegpt* dp, struct regional* regional,
 236         struct ub_packed_rrset_key* rrset, uint8_t lame);
 237
 238 /**
 239  * Add any RRset to delegpt.
 240  * Does not check for duplicates added.
 241  * @param dp: delegation point.
 242  * @param regional: where to allocate the info.
 243  * @param rrset: RRset to add, NS, A, AAAA.
 244  * @param lame: rrset is lame, disprefer it.
 245  * @return 0 on alloc error.
 246  */
 247 int delegpt_add_rrset(struct delegpt* dp, struct regional* regional,
 248         struct ub_packed_rrset_key* rrset, uint8_t lame);
 249
 250 /**
 251  * Add address to the delegation point. No servername is associated or checked.
 252  * @param dp: delegation point.
 253  * @param regional: where to allocate the info.
 254  * @param addr: the address.
 255  * @param addrlen: the length of addr.
 256  * @param bogus: if address is bogus.
 257  * @param lame: if address is lame.
 258  * @return false on error.
 259  */
 260 int delegpt_add_addr(struct delegpt* dp, struct regional* regional,
 261         struct sockaddr_storage* addr, socklen_t addrlen,
 262         uint8_t bogus, uint8_t lame);
 263
 264 /**
 265  * Find NS record in name list of delegation point.
 266  * @param dp: delegation point.
 267  * @param name: name of nameserver to look for, uncompressed wireformat.
 268  * @param namelen: length of name.
 269  * @return the ns structure or NULL if not found.
 270  */
 271 struct delegpt_ns* delegpt_find_ns(struct delegpt* dp, uint8_t* name,
 272         size_t namelen);
 273
 274 /**
 275  * Find address record in total list of delegation point.
 276  * @param dp: delegation point.
 277  * @param addr: address
 278  * @param addrlen: length of addr
 279  * @return the addr structure or NULL if not found.
 280  */
 281 struct delegpt_addr* delegpt_find_addr(struct delegpt* dp,
 282         struct sockaddr_storage* addr, socklen_t addrlen);
 283
 284 /**
 285  * Print the delegation point to the log. For debugging.
 286  * @param v: verbosity value that is needed to emit to log.
 287  * @param dp: delegation point.
 288  */
 289 void delegpt_log(enum verbosity_value v, struct delegpt* dp);
 290
 291 /** count NS and number missing for logging */
 292 void delegpt_count_ns(struct delegpt* dp, size_t* numns, size_t* missing);
 293
 294 /** count addresses, and number in result and available lists, for logging */
 295 void delegpt_count_addr(struct delegpt* dp, size_t* numaddr, size_t* numres,
 296         size_t* numavail);
 297
 298 /**
 299  * Add all usable targets to the result list.
 300  * @param dp: delegation point.
 301  */
 302 void delegpt_add_unused_targets(struct delegpt* dp);
 303
 304 /**
 305  * Count number of missing targets. These are ns names with no resolved flag.
 306  * @param dp: delegation point.
 307  * @return number of missing targets (or 0).
 308  */
 309 size_t delegpt_count_missing_targets(struct delegpt* dp);
 310
 311 /** count total number of targets in dp */
 312 size_t delegpt_count_targets(struct delegpt* dp);
 313
 314 /**
 315  * Create new delegation point from a dns message
 316  *
 317  * Note that this method does not actually test to see if the message is an
 318  * actual referral. It really is just checking to see if it can construct a
 319  * delegation point, so the message could be of some other type (some ANSWER
 320  * messages, some CNAME messages, generally.) Note that the resulting
 321  * DelegationPoint will contain targets for all "relevant" glue (i.e.,
 322  * address records whose ownernames match the target of one of the NS
 323  * records), so if policy dictates that some glue should be discarded beyond
 324  * that, discard it before calling this method. Note that this method will
 325  * find "glue" in either the ADDITIONAL section or the ANSWER section.
 326  *
 327  * @param msg: the dns message, referral.
 328  * @param regional: where to allocate delegation point.
 329  * @return new delegation point or NULL on alloc error, or if the
 330  *         message was not appropriate.
 331  */
 332 struct delegpt* delegpt_from_message(struct dns_msg* msg,
 333         struct regional* regional);
 334
 335 /**
 336  * Add negative message to delegation point.
 337  * @param dp: delegation point.
 338  * @param msg: the message added, marks off A or AAAA from an NS entry.
 339  */
 340 void delegpt_add_neg_msg(struct delegpt* dp, struct msgreply_entry* msg);
 341
 342 /**
 343  * Register the fact that there is no ipv6 and thus AAAAs are not going
 344  * to be queried for or be useful.
 345  * @param dp: the delegation point. Updated to reflect no ipv6.
 346  */
 347 void delegpt_no_ipv6(struct delegpt* dp);
 348
 349 /**
 350  * Register the fact that there is no ipv4 and thus As are not going
 351  * to be queried for or be useful.
 352  * @param dp: the delegation point. Updated to reflect no ipv4.
 353  */
 354 void delegpt_no_ipv4(struct delegpt* dp);
 355
 356 /**
 357  * create malloced delegation point, with the given name
 358  * @param name: uncompressed wireformat of degegpt name.
 359  * @return NULL on alloc failure
 360  */
 361 struct delegpt* delegpt_create_mlc(uint8_t* name);
 362
 363 /**
 364  * free malloced delegation point.
 365  * @param dp: must have been created with delegpt_create_mlc, free'd.
 366  */
 367 void delegpt_free_mlc(struct delegpt* dp);
 368
 369 /**
 370  * Set name of delegation point.
 371  * @param dp: delegation point. malloced.
 372  * @param name: name to use.
 373  * @return false on error.
 374  */
 375 int delegpt_set_name_mlc(struct delegpt* dp, uint8_t* name);
 376
 377 /**
 378  * add a name to malloced delegation point.
 379  * @param dp: must have been created with delegpt_create_mlc.
 380  * @param name: the name to add.
 381  * @param lame: the name is lame, disprefer.
 382  * @return false on error.
 383  */
 384 int delegpt_add_ns_mlc(struct delegpt* dp, uint8_t* name, uint8_t lame);
 385
 386 /**
 387  * add an address to a malloced delegation point.
 388  * @param dp: must have been created with delegpt_create_mlc.
 389  * @param addr: the address.
 390  * @param addrlen: the length of addr.
 391  * @param bogus: if address is bogus.
 392  * @param lame: if address is lame.
 393  * @return false on error.
 394  */
 395 int delegpt_add_addr_mlc(struct delegpt* dp, struct sockaddr_storage* addr,
 396         socklen_t addrlen, uint8_t bogus, uint8_t lame);
 397
 398 /**
 399  * Add target address to the delegation point.
 400  * @param dp: must have been created with delegpt_create_mlc.
 401  * @param name: name for which target was found (must be in nslist).
 402  *      This name is marked resolved.
 403  * @param namelen: length of name.
 404  * @param addr: the address.
 405  * @param addrlen: the length of addr.
 406  * @param bogus: security status for the address, pass true if bogus.
 407  * @param lame: address is lame.
 408  * @return false on error.
 409  */
 410 int delegpt_add_target_mlc(struct delegpt* dp, uint8_t* name, size_t namelen,
 411         struct sockaddr_storage* addr, socklen_t addrlen, uint8_t bogus,
 412         uint8_t lame);
 413
 414 /** get memory in use by dp */
 415 size_t delegpt_get_mem(struct delegpt* dp);
 416
 417 #endif /* ITERATOR_ITER_DELEGPT_H */