1 /* 2 * dnssec.h -- defines for the Domain Name System (SEC) (DNSSEC) 3 * 4 * Copyright (c) 2005-2008, NLnet Labs. All rights reserved. 5 * 6 * See LICENSE for the license. 7 * 8 * A bunch of defines that are used in the DNS 9 */ 10 11 /** 12 * \file dnssec.h 13 * 14 * This module contains base functions for DNSSEC operations 15 * (RFC4033 t/m RFC4035). 16 * 17 * Since those functions heavily rely op cryptographic operations, 18 * this module is dependent on openssl. 19 * 20 */ 21 22 23 #ifndef LDNS_DNSSEC_H 24 #define LDNS_DNSSEC_H 25 26 #ifdef HAVE_SSL 27 #include <openssl/ssl.h> 28 #include <openssl/evp.h> 29 #endif /* HAVE_SSL */ 30 #include <ldns/common.h> 31 #include <ldns/packet.h> 32 #include <ldns/keys.h> 33 #include <ldns/zone.h> 34 #include <ldns/resolver.h> 35 #include <ldns/dnssec_zone.h> 36 37 #ifdef __cplusplus 38 extern "C" { 39 #endif 40 41 #define LDNS_MAX_KEYLEN 2048 42 #define LDNS_DNSSEC_KEYPROTO 3 43 /* default time before sigs expire */ 44 #define LDNS_DEFAULT_EXP_TIME 2419200 /* 4 weeks */ 45 46 /** return values for the old-signature callback */ 47 #define LDNS_SIGNATURE_LEAVE_ADD_NEW 0 48 #define LDNS_SIGNATURE_LEAVE_NO_ADD 1 49 #define LDNS_SIGNATURE_REMOVE_ADD_NEW 2 50 #define LDNS_SIGNATURE_REMOVE_NO_ADD 3 51 52 /** 53 * Returns the first RRSIG rr that corresponds to the rrset 54 * with the given name and type 55 * 56 * \param[in] name The dname of the RRset covered by the RRSIG to find 57 * \param[in] type The type of the RRset covered by the RRSIG to find 58 * \param[in] rrs List of rrs to search in 59 * \returns Pointer to the first RRsig ldns_rr found, or NULL if it is 60 * not present 61 */ 62 ldns_rr *ldns_dnssec_get_rrsig_for_name_and_type(const ldns_rdf *name, 63 const ldns_rr_type type, 64 const ldns_rr_list *rrs); 65 66 /** 67 * Returns the DNSKEY that corresponds to the given RRSIG rr from the list, if 68 * any 69 * 70 * \param[in] rrsig The rrsig to find the DNSKEY for 71 * \param[in] rrs The rr list to find the key in 72 * \return The DNSKEY that corresponds to the given RRSIG, or NULL if it was 73 * not found. 74 */ 75 ldns_rr *ldns_dnssec_get_dnskey_for_rrsig(const ldns_rr *rrsig, const ldns_rr_list *rrs); 76 77 /** 78 * Returns the rdata field that contains the bitmap of the covered types of 79 * the given NSEC record 80 * 81 * \param[in] nsec The nsec to get the covered type bitmap of 82 * \return An ldns_rdf containing the bitmap, or NULL on error 83 */ 84 ldns_rdf *ldns_nsec_get_bitmap(ldns_rr *nsec); 85 86 87 #define LDNS_NSEC3_MAX_ITERATIONS 65535 88 89 /** 90 * Returns the dname of the closest (provable) encloser 91 */ 92 ldns_rdf * 93 ldns_dnssec_nsec3_closest_encloser(ldns_rdf *qname, 94 ldns_rr_type qtype, 95 ldns_rr_list *nsec3s); 96 97 /** 98 * Checks whether the packet contains rrsigs 99 */ 100 bool 101 ldns_dnssec_pkt_has_rrsigs(const ldns_pkt *pkt); 102 103 /** 104 * Returns a ldns_rr_list containing the signatures covering the given name 105 * and type 106 */ 107 ldns_rr_list *ldns_dnssec_pkt_get_rrsigs_for_name_and_type(const ldns_pkt *pkt, ldns_rdf *name, ldns_rr_type type); 108 109 /** 110 * Returns a ldns_rr_list containing the signatures covering the given type 111 */ 112 ldns_rr_list *ldns_dnssec_pkt_get_rrsigs_for_type(const ldns_pkt *pkt, ldns_rr_type type); 113 114 /** 115 * calculates a keytag of a key for use in DNSSEC. 116 * 117 * \param[in] key the key as an RR to use for the calc. 118 * \return the keytag 119 */ 120 uint16_t ldns_calc_keytag(const ldns_rr *key); 121 122 /** 123 * Calculates keytag of DNSSEC key, operates on wireformat rdata. 124 * \param[in] key the key as uncompressed wireformat rdata. 125 * \param[in] keysize length of key data. 126 * \return the keytag 127 */ 128 uint16_t ldns_calc_keytag_raw(uint8_t* key, size_t keysize); 129 130 #ifdef HAVE_SSL 131 /** 132 * converts a buffer holding key material to a DSA key in openssl. 133 * 134 * \param[in] key the key to convert 135 * \return a DSA * structure with the key material 136 */ 137 DSA *ldns_key_buf2dsa(ldns_buffer *key); 138 /** 139 * Like ldns_key_buf2dsa, but uses raw buffer. 140 * \param[in] key the uncompressed wireformat of the key. 141 * \param[in] len length of key data 142 * \return a DSA * structure with the key material 143 */ 144 DSA *ldns_key_buf2dsa_raw(unsigned char* key, size_t len); 145 146 /** 147 * Utility function to calculate hash using generic EVP_MD pointer. 148 * \param[in] data the data to hash. 149 * \param[in] len length of data. 150 * \param[out] dest the destination of the hash, must be large enough. 151 * \param[in] md the message digest to use. 152 * \return true if worked, false on failure. 153 */ 154 int ldns_digest_evp(unsigned char* data, unsigned int len, 155 unsigned char* dest, const EVP_MD* md); 156 157 /** 158 * Converts a holding buffer with key material to EVP PKEY in openssl. 159 * Only available if ldns was compiled with GOST. 160 * \param[in] key data to convert 161 * \param[in] keylen length of the key data 162 * \return the key or NULL on error. 163 */ 164 EVP_PKEY* ldns_gost2pkey_raw(unsigned char* key, size_t keylen); 165 166 /** 167 * Converts a holding buffer with key material to EVP PKEY in openssl. 168 * Only available if ldns was compiled with ECDSA. 169 * \param[in] key data to convert 170 * \param[in] keylen length of the key data 171 * \param[in] algo precise algorithm to initialize ECC group values. 172 * \return the key or NULL on error. 173 */ 174 EVP_PKEY* ldns_ecdsa2pkey_raw(unsigned char* key, size_t keylen, uint8_t algo); 175 176 #endif /* HAVE_SSL */ 177 178 #ifdef HAVE_SSL 179 /** 180 * converts a buffer holding key material to a RSA key in openssl. 181 * 182 * \param[in] key the key to convert 183 * \return a RSA * structure with the key material 184 */ 185 RSA *ldns_key_buf2rsa(ldns_buffer *key); 186 187 /** 188 * Like ldns_key_buf2rsa, but uses raw buffer. 189 * \param[in] key the uncompressed wireformat of the key. 190 * \param[in] len length of key data 191 * \return a RSA * structure with the key material 192 */ 193 RSA *ldns_key_buf2rsa_raw(unsigned char* key, size_t len); 194 #endif /* HAVE_SSL */ 195 196 /** 197 * returns a new DS rr that represents the given key rr. 198 * 199 * \param[in] *key the key to convert 200 * \param[in] h the hash to use LDNS_SHA1/LDNS_SHA256 201 * \return ldns_rr* a new rr pointer to a DS 202 */ 203 ldns_rr *ldns_key_rr2ds(const ldns_rr *key, ldns_hash h); 204 205 /** 206 * Create the type bitmap for an NSEC(3) record 207 */ 208 ldns_rdf * 209 ldns_dnssec_create_nsec_bitmap(ldns_rr_type rr_type_list[], 210 size_t size, 211 ldns_rr_type nsec_type); 212 213 /** 214 * Creates NSEC 215 */ 216 ldns_rr * 217 ldns_dnssec_create_nsec(ldns_dnssec_name *from, 218 ldns_dnssec_name *to, 219 ldns_rr_type nsec_type); 220 221 222 /** 223 * Creates NSEC3 224 */ 225 ldns_rr * 226 ldns_dnssec_create_nsec3(ldns_dnssec_name *from, 227 ldns_dnssec_name *to, 228 ldns_rdf *zone_name, 229 uint8_t algorithm, 230 uint8_t flags, 231 uint16_t iterations, 232 uint8_t salt_length, 233 uint8_t *salt); 234 235 /** 236 * Create a NSEC record 237 * \param[in] cur_owner the current owner which should be taken as the starting point 238 * \param[in] next_owner the rrlist which the nsec rr should point to 239 * \param[in] rrs all rrs from the zone, to find all RR types of cur_owner in 240 * \return a ldns_rr with the nsec record in it 241 */ 242 ldns_rr * ldns_create_nsec(ldns_rdf *cur_owner, ldns_rdf *next_owner, ldns_rr_list *rrs); 243 244 /** 245 * Calculates the hashed name using the given parameters 246 * \param[in] *name The owner name to calculate the hash for 247 * \param[in] algorithm The hash algorithm to use 248 * \param[in] iterations The number of hash iterations to use 249 * \param[in] salt_length The length of the salt in bytes 250 * \param[in] salt The salt to use 251 * \return The hashed owner name rdf, without the domain name 252 */ 253 ldns_rdf *ldns_nsec3_hash_name(ldns_rdf *name, uint8_t algorithm, uint16_t iterations, uint8_t salt_length, uint8_t *salt); 254 255 /** 256 * Sets all the NSEC3 options. The rr to set them in must be initialized with _new() and 257 * type LDNS_RR_TYPE_NSEC3 258 * \param[in] *rr The RR to set the values in 259 * \param[in] algorithm The NSEC3 hash algorithm 260 * \param[in] flags The flags field 261 * \param[in] iterations The number of hash iterations 262 * \param[in] salt_length The length of the salt in bytes 263 * \param[in] salt The salt bytes 264 */ 265 void ldns_nsec3_add_param_rdfs(ldns_rr *rr, 266 uint8_t algorithm, 267 uint8_t flags, 268 uint16_t iterations, 269 uint8_t salt_length, 270 uint8_t *salt); 271 272 /* this will NOT return the NSEC3 completed, you will have to run the 273 finalize function on the rrlist later! */ 274 ldns_rr * 275 ldns_create_nsec3(ldns_rdf *cur_owner, 276 ldns_rdf *cur_zone, 277 ldns_rr_list *rrs, 278 uint8_t algorithm, 279 uint8_t flags, 280 uint16_t iterations, 281 uint8_t salt_length, 282 uint8_t *salt, 283 bool emptynonterminal); 284 285 /** 286 * Returns the hash algorithm used in the given NSEC3 RR 287 * \param[in] *nsec3_rr The RR to read from 288 * \return The algorithm identifier, or 0 on error 289 */ 290 uint8_t ldns_nsec3_algorithm(const ldns_rr *nsec3_rr); 291 292 /** 293 * Returns flags field 294 */ 295 uint8_t 296 ldns_nsec3_flags(const ldns_rr *nsec3_rr); 297 298 /** 299 * Returns true if the opt-out flag has been set in the given NSEC3 RR 300 * \param[in] *nsec3_rr The RR to read from 301 * \return true if the RR has type NSEC3 and the opt-out bit has been set, false otherwise 302 */ 303 bool ldns_nsec3_optout(const ldns_rr *nsec3_rr); 304 305 /** 306 * Returns the number of hash iterations used in the given NSEC3 RR 307 * \param[in] *nsec3_rr The RR to read from 308 * \return The number of iterations 309 */ 310 uint16_t ldns_nsec3_iterations(const ldns_rr *nsec3_rr); 311 312 /** 313 * Returns the salt used in the given NSEC3 RR 314 * \param[in] *nsec3_rr The RR to read from 315 * \return The salt rdf, or NULL on error 316 */ 317 ldns_rdf *ldns_nsec3_salt(const ldns_rr *nsec3_rr); 318 319 /** 320 * Returns the length of the salt used in the given NSEC3 RR 321 * \param[in] *nsec3_rr The RR to read from 322 * \return The length of the salt in bytes 323 */ 324 uint8_t ldns_nsec3_salt_length(const ldns_rr *nsec3_rr); 325 326 /** 327 * Returns the salt bytes used in the given NSEC3 RR 328 * \param[in] *nsec3_rr The RR to read from 329 * \return The salt in bytes, this is alloced, so you need to free it 330 */ 331 uint8_t *ldns_nsec3_salt_data(const ldns_rr *nsec3_rr); 332 333 /** 334 * Returns the first label of the next ownername in the NSEC3 chain (ie. without the domain) 335 * \param[in] nsec3_rr The RR to read from 336 * \return The first label of the next owner name in the NSEC3 chain, or NULL on error 337 */ 338 ldns_rdf *ldns_nsec3_next_owner(const ldns_rr *nsec3_rr); 339 340 /** 341 * Returns the bitmap specifying the covered types of the given NSEC3 RR 342 * \param[in] *nsec3_rr The RR to read from 343 * \return The covered type bitmap rdf 344 */ 345 ldns_rdf *ldns_nsec3_bitmap(const ldns_rr *nsec3_rr); 346 347 /** 348 * Calculates the hashed name using the parameters of the given NSEC3 RR 349 * \param[in] *nsec The RR to use the parameters from 350 * \param[in] *name The owner name to calculate the hash for 351 * \return The hashed owner name rdf, without the domain name 352 */ 353 ldns_rdf *ldns_nsec3_hash_name_frm_nsec3(const ldns_rr *nsec, ldns_rdf *name); 354 355 /** 356 * Checks coverage of NSEC RR type bitmap 357 * \param[in] nsec_bitmap The NSEC bitmap rdata field to check 358 * \param[in] type The type to check 359 * \return true if the NSEC RR covers the type 360 */ 361 bool ldns_nsec_bitmap_covers_type(const ldns_rdf *nsec_bitmap, ldns_rr_type type); 362 363 /** 364 * Checks coverage of NSEC(3) RR name span 365 * Remember that nsec and name must both be in canonical form (ie use 366 * \ref ldns_rr2canonical and \ref ldns_dname2canonical prior to calling this 367 * function) 368 * 369 * \param[in] nsec The NSEC RR to check 370 * \param[in] name The owner dname to check, if the nsec record is a NSEC3 record, this should be the hashed name 371 * \return true if the NSEC RR covers the owner name 372 */ 373 bool ldns_nsec_covers_name(const ldns_rr *nsec, const ldns_rdf *name); 374 375 #ifdef HAVE_SSL 376 /** 377 * verify a packet 378 * \param[in] p the packet 379 * \param[in] t the rr set type to check 380 * \param[in] o the rr set name to check 381 * \param[in] k list of keys 382 * \param[in] s list of sigs (may be null) 383 * \param[out] good_keys keys which validated the packet 384 * \return status 385 * 386 */ 387 ldns_status ldns_pkt_verify(ldns_pkt *p, ldns_rr_type t, ldns_rdf *o, ldns_rr_list *k, ldns_rr_list *s, ldns_rr_list *good_keys); 388 #endif 389 390 /** 391 * chains nsec3 list 392 */ 393 ldns_status 394 ldns_dnssec_chain_nsec3_list(ldns_rr_list *nsec3_rrs); 395 396 /** 397 * compare for nsec3 sort 398 */ 399 int 400 qsort_rr_compare_nsec3(const void *a, const void *b); 401 402 /** 403 * sort nsec3 list 404 */ 405 void 406 ldns_rr_list_sort_nsec3(ldns_rr_list *unsorted); 407 408 /** 409 * Default callback function to always leave present signatures, and 410 * add new ones 411 * \param[in] sig The signature to check for removal (unused) 412 * \param[in] n Optional argument (unused) 413 * \return LDNS_SIGNATURE_LEAVE_ADD_NEW 414 */ 415 int ldns_dnssec_default_add_to_signatures(ldns_rr *sig, void *n); 416 /** 417 * Default callback function to always leave present signatures, and 418 * add no new ones for the keys of these signatures 419 * \param[in] sig The signature to check for removal (unused) 420 * \param[in] n Optional argument (unused) 421 * \return LDNS_SIGNATURE_LEAVE_NO_ADD 422 */ 423 int ldns_dnssec_default_leave_signatures(ldns_rr *sig, void *n); 424 /** 425 * Default callback function to always remove present signatures, but 426 * add no new ones 427 * \param[in] sig The signature to check for removal (unused) 428 * \param[in] n Optional argument (unused) 429 * \return LDNS_SIGNATURE_REMOVE_NO_ADD 430 */ 431 int ldns_dnssec_default_delete_signatures(ldns_rr *sig, void *n); 432 /** 433 * Default callback function to always leave present signatures, and 434 * add new ones 435 * \param[in] sig The signature to check for removal (unused) 436 * \param[in] n Optional argument (unused) 437 * \return LDNS_SIGNATURE_REMOVE_ADD_NEW 438 */ 439 int ldns_dnssec_default_replace_signatures(ldns_rr *sig, void *n); 440 441 #ifdef HAVE_SSL 442 /** 443 * Converts the DSA signature from ASN1 representation (RFC2459, as 444 * used by OpenSSL) to raw signature data as used in DNS (rfc2536) 445 * 446 * \param[in] sig The signature in RFC2459 format 447 * \param[in] sig_len The length of the signature 448 * \return a new rdf with the signature 449 */ 450 ldns_rdf * 451 ldns_convert_dsa_rrsig_asn12rdf(const ldns_buffer *sig, 452 const long sig_len); 453 454 /** 455 * Converts the RRSIG signature RDF (in rfc2536 format) to a buffer 456 * with the signature in rfc2459 format 457 * 458 * \param[out] target_buffer buffer to place the signature data 459 * \param[in] sig_rdf The signature rdf to convert 460 * \return LDNS_STATUS_OK on success, error code otherwise 461 */ 462 ldns_status 463 ldns_convert_dsa_rrsig_rdf2asn1(ldns_buffer *target_buffer, 464 const ldns_rdf *sig_rdf); 465 466 /** 467 * Converts the ECDSA signature from ASN1 representation (as 468 * used by OpenSSL) to raw signature data as used in DNS 469 * This routine is only present if ldns is compiled with ecdsa support. 470 * 471 * \param[in] sig The signature in ASN1 format 472 * \param[in] sig_len The length of the signature 473 * \return a new rdf with the signature 474 */ 475 ldns_rdf * 476 ldns_convert_ecdsa_rrsig_asn12rdf(const ldns_buffer *sig, const long sig_len); 477 478 /** 479 * Converts the RRSIG signature RDF (from DNS) to a buffer with the 480 * signature in ASN1 format as openssl uses it. 481 * This routine is only present if ldns is compiled with ecdsa support. 482 * 483 * \param[out] target_buffer buffer to place the signature data in ASN1. 484 * \param[in] sig_rdf The signature rdf to convert 485 * \return LDNS_STATUS_OK on success, error code otherwise 486 */ 487 ldns_status 488 ldns_convert_ecdsa_rrsig_rdf2asn1(ldns_buffer *target_buffer, 489 const ldns_rdf *sig_rdf); 490 491 #endif /* HAVE_SSL */ 492 493 #ifdef __cplusplus 494 } 495 #endif 496 497 #endif /* LDNS_DNSSEC_H */ 498