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 #include <ldns/common.h> 27 #if LDNS_BUILD_CONFIG_HAVE_SSL 28 #include <openssl/ssl.h> 29 #include <openssl/evp.h> 30 #endif /* LDNS_BUILD_CONFIG_HAVE_SSL */ 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 #if LDNS_BUILD_CONFIG_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 /* LDNS_BUILD_CONFIG_HAVE_SSL */ 177 178 #if LDNS_BUILD_CONFIG_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 /* LDNS_BUILD_CONFIG_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 * returns whether a rrset of the given type is found in the rrsets. 215 * 216 * \param[in] rrsets the rrsets to be tested 217 * \param[in] type the type to test for 218 * \return int 1 if the type was found, 0 otherwise. 219 */ 220 int 221 ldns_dnssec_rrsets_contains_type (ldns_dnssec_rrsets *rrsets, ldns_rr_type type); 222 223 /** 224 * Creates NSEC 225 */ 226 ldns_rr * 227 ldns_dnssec_create_nsec(ldns_dnssec_name *from, 228 ldns_dnssec_name *to, 229 ldns_rr_type nsec_type); 230 231 232 /** 233 * Creates NSEC3 234 */ 235 ldns_rr * 236 ldns_dnssec_create_nsec3(ldns_dnssec_name *from, 237 ldns_dnssec_name *to, 238 ldns_rdf *zone_name, 239 uint8_t algorithm, 240 uint8_t flags, 241 uint16_t iterations, 242 uint8_t salt_length, 243 uint8_t *salt); 244 245 /** 246 * Create a NSEC record 247 * \param[in] cur_owner the current owner which should be taken as the starting point 248 * \param[in] next_owner the rrlist which the nsec rr should point to 249 * \param[in] rrs all rrs from the zone, to find all RR types of cur_owner in 250 * \return a ldns_rr with the nsec record in it 251 */ 252 ldns_rr * ldns_create_nsec(ldns_rdf *cur_owner, ldns_rdf *next_owner, ldns_rr_list *rrs); 253 254 /** 255 * Calculates the hashed name using the given parameters 256 * \param[in] *name The owner name to calculate the hash for 257 * \param[in] algorithm The hash algorithm to use 258 * \param[in] iterations The number of hash iterations to use 259 * \param[in] salt_length The length of the salt in bytes 260 * \param[in] salt The salt to use 261 * \return The hashed owner name rdf, without the domain name 262 */ 263 ldns_rdf *ldns_nsec3_hash_name(ldns_rdf *name, uint8_t algorithm, uint16_t iterations, uint8_t salt_length, uint8_t *salt); 264 265 /** 266 * Sets all the NSEC3 options. The rr to set them in must be initialized with _new() and 267 * type LDNS_RR_TYPE_NSEC3 268 * \param[in] *rr The RR to set the values in 269 * \param[in] algorithm The NSEC3 hash algorithm 270 * \param[in] flags The flags field 271 * \param[in] iterations The number of hash iterations 272 * \param[in] salt_length The length of the salt in bytes 273 * \param[in] salt The salt bytes 274 */ 275 void ldns_nsec3_add_param_rdfs(ldns_rr *rr, 276 uint8_t algorithm, 277 uint8_t flags, 278 uint16_t iterations, 279 uint8_t salt_length, 280 uint8_t *salt); 281 282 /* this will NOT return the NSEC3 completed, you will have to run the 283 finalize function on the rrlist later! */ 284 ldns_rr * 285 ldns_create_nsec3(ldns_rdf *cur_owner, 286 ldns_rdf *cur_zone, 287 ldns_rr_list *rrs, 288 uint8_t algorithm, 289 uint8_t flags, 290 uint16_t iterations, 291 uint8_t salt_length, 292 uint8_t *salt, 293 bool emptynonterminal); 294 295 /** 296 * Returns the hash algorithm used in the given NSEC3 RR 297 * \param[in] *nsec3_rr The RR to read from 298 * \return The algorithm identifier, or 0 on error 299 */ 300 uint8_t ldns_nsec3_algorithm(const ldns_rr *nsec3_rr); 301 302 /** 303 * Returns flags field 304 */ 305 uint8_t 306 ldns_nsec3_flags(const ldns_rr *nsec3_rr); 307 308 /** 309 * Returns true if the opt-out flag has been set in the given NSEC3 RR 310 * \param[in] *nsec3_rr The RR to read from 311 * \return true if the RR has type NSEC3 and the opt-out bit has been set, false otherwise 312 */ 313 bool ldns_nsec3_optout(const ldns_rr *nsec3_rr); 314 315 /** 316 * Returns the number of hash iterations used in the given NSEC3 RR 317 * \param[in] *nsec3_rr The RR to read from 318 * \return The number of iterations 319 */ 320 uint16_t ldns_nsec3_iterations(const ldns_rr *nsec3_rr); 321 322 /** 323 * Returns the salt used in the given NSEC3 RR 324 * \param[in] *nsec3_rr The RR to read from 325 * \return The salt rdf, or NULL on error 326 */ 327 ldns_rdf *ldns_nsec3_salt(const ldns_rr *nsec3_rr); 328 329 /** 330 * Returns the length of the salt used in the given NSEC3 RR 331 * \param[in] *nsec3_rr The RR to read from 332 * \return The length of the salt in bytes 333 */ 334 uint8_t ldns_nsec3_salt_length(const ldns_rr *nsec3_rr); 335 336 /** 337 * Returns the salt bytes used in the given NSEC3 RR 338 * \param[in] *nsec3_rr The RR to read from 339 * \return The salt in bytes, this is alloced, so you need to free it 340 */ 341 uint8_t *ldns_nsec3_salt_data(const ldns_rr *nsec3_rr); 342 343 /** 344 * Returns the first label of the next ownername in the NSEC3 chain (ie. without the domain) 345 * \param[in] nsec3_rr The RR to read from 346 * \return The first label of the next owner name in the NSEC3 chain, or NULL on error 347 */ 348 ldns_rdf *ldns_nsec3_next_owner(const ldns_rr *nsec3_rr); 349 350 /** 351 * Returns the bitmap specifying the covered types of the given NSEC3 RR 352 * \param[in] *nsec3_rr The RR to read from 353 * \return The covered type bitmap rdf 354 */ 355 ldns_rdf *ldns_nsec3_bitmap(const ldns_rr *nsec3_rr); 356 357 /** 358 * Calculates the hashed name using the parameters of the given NSEC3 RR 359 * \param[in] *nsec The RR to use the parameters from 360 * \param[in] *name The owner name to calculate the hash for 361 * \return The hashed owner name rdf, without the domain name 362 */ 363 ldns_rdf *ldns_nsec3_hash_name_frm_nsec3(const ldns_rr *nsec, ldns_rdf *name); 364 365 /** 366 * Checks coverage of NSEC RR type bitmap 367 * \param[in] nsec_bitmap The NSEC bitmap rdata field to check 368 * \param[in] type The type to check 369 * \return true if the NSEC RR covers the type 370 */ 371 bool ldns_nsec_bitmap_covers_type(const ldns_rdf *nsec_bitmap, ldns_rr_type type); 372 373 /** 374 * Checks coverage of NSEC(3) RR name span 375 * Remember that nsec and name must both be in canonical form (ie use 376 * \ref ldns_rr2canonical and \ref ldns_dname2canonical prior to calling this 377 * function) 378 * 379 * \param[in] nsec The NSEC RR to check 380 * \param[in] name The owner dname to check, if the nsec record is a NSEC3 record, this should be the hashed name 381 * \return true if the NSEC RR covers the owner name 382 */ 383 bool ldns_nsec_covers_name(const ldns_rr *nsec, const ldns_rdf *name); 384 385 #if LDNS_BUILD_CONFIG_HAVE_SSL 386 /** 387 * verify a packet 388 * \param[in] p the packet 389 * \param[in] t the rr set type to check 390 * \param[in] o the rr set name to check 391 * \param[in] k list of keys 392 * \param[in] s list of sigs (may be null) 393 * \param[out] good_keys keys which validated the packet 394 * \return status 395 * 396 */ 397 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); 398 #endif 399 400 /** 401 * chains nsec3 list 402 */ 403 ldns_status 404 ldns_dnssec_chain_nsec3_list(ldns_rr_list *nsec3_rrs); 405 406 /** 407 * compare for nsec3 sort 408 */ 409 int 410 qsort_rr_compare_nsec3(const void *a, const void *b); 411 412 /** 413 * sort nsec3 list 414 */ 415 void 416 ldns_rr_list_sort_nsec3(ldns_rr_list *unsorted); 417 418 /** 419 * Default callback function to always leave present signatures, and 420 * add new ones 421 * \param[in] sig The signature to check for removal (unused) 422 * \param[in] n Optional argument (unused) 423 * \return LDNS_SIGNATURE_LEAVE_ADD_NEW 424 */ 425 int ldns_dnssec_default_add_to_signatures(ldns_rr *sig, void *n); 426 /** 427 * Default callback function to always leave present signatures, and 428 * add no new ones for the keys of these signatures 429 * \param[in] sig The signature to check for removal (unused) 430 * \param[in] n Optional argument (unused) 431 * \return LDNS_SIGNATURE_LEAVE_NO_ADD 432 */ 433 int ldns_dnssec_default_leave_signatures(ldns_rr *sig, void *n); 434 /** 435 * Default callback function to always remove present signatures, but 436 * add no new ones 437 * \param[in] sig The signature to check for removal (unused) 438 * \param[in] n Optional argument (unused) 439 * \return LDNS_SIGNATURE_REMOVE_NO_ADD 440 */ 441 int ldns_dnssec_default_delete_signatures(ldns_rr *sig, void *n); 442 /** 443 * Default callback function to always leave present signatures, and 444 * add new ones 445 * \param[in] sig The signature to check for removal (unused) 446 * \param[in] n Optional argument (unused) 447 * \return LDNS_SIGNATURE_REMOVE_ADD_NEW 448 */ 449 int ldns_dnssec_default_replace_signatures(ldns_rr *sig, void *n); 450 451 #if LDNS_BUILD_CONFIG_HAVE_SSL 452 /** 453 * Converts the DSA signature from ASN1 representation (RFC2459, as 454 * used by OpenSSL) to raw signature data as used in DNS (rfc2536) 455 * 456 * \param[in] sig The signature in RFC2459 format 457 * \param[in] sig_len The length of the signature 458 * \return a new rdf with the signature 459 */ 460 ldns_rdf * 461 ldns_convert_dsa_rrsig_asn12rdf(const ldns_buffer *sig, 462 const long sig_len); 463 464 /** 465 * Converts the RRSIG signature RDF (in rfc2536 format) to a buffer 466 * with the signature in rfc2459 format 467 * 468 * \param[out] target_buffer buffer to place the signature data 469 * \param[in] sig_rdf The signature rdf to convert 470 * \return LDNS_STATUS_OK on success, error code otherwise 471 */ 472 ldns_status 473 ldns_convert_dsa_rrsig_rdf2asn1(ldns_buffer *target_buffer, 474 const ldns_rdf *sig_rdf); 475 476 /** 477 * Converts the ECDSA signature from ASN1 representation (as 478 * used by OpenSSL) to raw signature data as used in DNS 479 * This routine is only present if ldns is compiled with ecdsa support. 480 * 481 * \param[in] sig The signature in ASN1 format 482 * \param[in] sig_len The length of the signature 483 * \return a new rdf with the signature 484 */ 485 ldns_rdf * 486 ldns_convert_ecdsa_rrsig_asn12rdf(const ldns_buffer *sig, const long sig_len); 487 488 /** 489 * Converts the RRSIG signature RDF (from DNS) to a buffer with the 490 * signature in ASN1 format as openssl uses it. 491 * This routine is only present if ldns is compiled with ecdsa support. 492 * 493 * \param[out] target_buffer buffer to place the signature data in ASN1. 494 * \param[in] sig_rdf The signature rdf to convert 495 * \return LDNS_STATUS_OK on success, error code otherwise 496 */ 497 ldns_status 498 ldns_convert_ecdsa_rrsig_rdf2asn1(ldns_buffer *target_buffer, 499 const ldns_rdf *sig_rdf); 500 501 #endif /* LDNS_BUILD_CONFIG_HAVE_SSL */ 502 503 #ifdef __cplusplus 504 } 505 #endif 506 507 #endif /* LDNS_DNSSEC_H */ 508