src/resolve/resolved-dns-rr.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   Copyright 2014 Lennart Poettering
   6  ***/
   7
   8 #include <netinet/in.h>
   9
  10 #include "bitmap.h"
  11 #include "dns-type.h"
  12 #include "hashmap.h"
  13 #include "in-addr-util.h"
  14 #include "list.h"
  15 #include "string-util.h"
  16
  17 typedef struct DnsResourceKey DnsResourceKey;
  18 typedef struct DnsResourceRecord DnsResourceRecord;
  19 typedef struct DnsTxtItem DnsTxtItem;
  20
  21 /* DNSKEY RR flags */
  22 #define DNSKEY_FLAG_SEP      (UINT16_C(1) << 0)
  23 #define DNSKEY_FLAG_REVOKE   (UINT16_C(1) << 7)
  24 #define DNSKEY_FLAG_ZONE_KEY (UINT16_C(1) << 8)
  25
  26 /* mDNS RR flags */
  27 #define MDNS_RR_CACHE_FLUSH  (UINT16_C(1) << 15)
  28
  29 /* DNSSEC algorithm identifiers, see
  30  * http://tools.ietf.org/html/rfc4034#appendix-A.1 and
  31  * https://www.iana.org/assignments/dns-sec-alg-numbers/dns-sec-alg-numbers.xhtml */
  32 enum {
  33         DNSSEC_ALGORITHM_RSAMD5 = 1,
  34         DNSSEC_ALGORITHM_DH,
  35         DNSSEC_ALGORITHM_DSA,
  36         DNSSEC_ALGORITHM_ECC,
  37         DNSSEC_ALGORITHM_RSASHA1,
  38         DNSSEC_ALGORITHM_DSA_NSEC3_SHA1,
  39         DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1,
  40         DNSSEC_ALGORITHM_RSASHA256 = 8,        /* RFC 5702 */
  41         DNSSEC_ALGORITHM_RSASHA512 = 10,       /* RFC 5702 */
  42         DNSSEC_ALGORITHM_ECC_GOST = 12,        /* RFC 5933 */
  43         DNSSEC_ALGORITHM_ECDSAP256SHA256 = 13, /* RFC 6605 */
  44         DNSSEC_ALGORITHM_ECDSAP384SHA384 = 14, /* RFC 6605 */
  45         DNSSEC_ALGORITHM_ED25519 = 15,         /* RFC 8080 */
  46         DNSSEC_ALGORITHM_ED448 = 16,           /* RFC 8080 */
  47         DNSSEC_ALGORITHM_INDIRECT = 252,
  48         DNSSEC_ALGORITHM_PRIVATEDNS,
  49         DNSSEC_ALGORITHM_PRIVATEOID,
  50         _DNSSEC_ALGORITHM_MAX_DEFINED
  51 };
  52
  53 /* DNSSEC digest identifiers, see
  54  * https://www.iana.org/assignments/ds-rr-types/ds-rr-types.xhtml */
  55 enum {
  56         DNSSEC_DIGEST_SHA1 = 1,
  57         DNSSEC_DIGEST_SHA256 = 2,              /* RFC 4509 */
  58         DNSSEC_DIGEST_GOST_R_34_11_94 = 3,     /* RFC 5933 */
  59         DNSSEC_DIGEST_SHA384 = 4,              /* RFC 6605 */
  60         _DNSSEC_DIGEST_MAX_DEFINED
  61 };
  62
  63 /* DNSSEC NSEC3 hash algorithms, see
  64  * https://www.iana.org/assignments/dnssec-nsec3-parameters/dnssec-nsec3-parameters.xhtml */
  65 enum {
  66         NSEC3_ALGORITHM_SHA1 = 1,
  67         _NSEC3_ALGORITHM_MAX_DEFINED
  68 };
  69
  70 struct DnsResourceKey {
  71         unsigned n_ref; /* (unsigned -1) for const keys, see below */
  72         uint16_t class, type;
  73         char *_name; /* don't access directly, use dns_resource_key_name()! */
  74 };
  75
  76 /* Creates a temporary resource key. This is only useful to quickly
  77  * look up something, without allocating a full DnsResourceKey object
  78  * for it. Note that it is not OK to take references to this kind of
  79  * resource key object. */
  80 #define DNS_RESOURCE_KEY_CONST(c, t, n)                 \
  81         ((DnsResourceKey) {                             \
  82                 .n_ref = (unsigned) -1,                 \
  83                 .class = c,                             \
  84                 .type = t,                              \
  85                 ._name = (char*) n,                     \
  86         })
  87
  88 struct DnsTxtItem {
  89         size_t length;
  90         LIST_FIELDS(DnsTxtItem, items);
  91         uint8_t data[];
  92 };
  93
  94 struct DnsResourceRecord {
  95         unsigned n_ref;
  96         DnsResourceKey *key;
  97
  98         char *to_string;
  99
 100         uint32_t ttl;
 101         usec_t expiry; /* RRSIG signature expiry */
 102
 103         /* How many labels to strip to determine "signer" of the RRSIG (aka, the zone). -1 if not signed. */
 104         unsigned n_skip_labels_signer;
 105         /* How many labels to strip to determine "synthesizing source" of this RR, i.e. the wildcard's immediate parent. -1 if not signed. */
 106         unsigned n_skip_labels_source;
 107
 108         bool unparseable:1;
 109
 110         bool wire_format_canonical:1;
 111         void *wire_format;
 112         size_t wire_format_size;
 113         size_t wire_format_rdata_offset;
 114
 115         union {
 116                 struct {
 117                         void *data;
 118                         size_t data_size;
 119                 } generic, opt;
 120
 121                 struct {
 122                         uint16_t priority;
 123                         uint16_t weight;
 124                         uint16_t port;
 125                         char *name;
 126                 } srv;
 127
 128                 struct {
 129                         char *name;
 130                 } ptr, ns, cname, dname;
 131
 132                 struct {
 133                         char *cpu;
 134                         char *os;
 135                 } hinfo;
 136
 137                 struct {
 138                         DnsTxtItem *items;
 139                 } txt, spf;
 140
 141                 struct {
 142                         struct in_addr in_addr;
 143                 } a;
 144
 145                 struct {
 146                         struct in6_addr in6_addr;
 147                 } aaaa;
 148
 149                 struct {
 150                         char *mname;
 151                         char *rname;
 152                         uint32_t serial;
 153                         uint32_t refresh;
 154                         uint32_t retry;
 155                         uint32_t expire;
 156                         uint32_t minimum;
 157                 } soa;
 158
 159                 struct {
 160                         uint16_t priority;
 161                         char *exchange;
 162                 } mx;
 163
 164                 /* https://tools.ietf.org/html/rfc1876 */
 165                 struct {
 166                         uint8_t version;
 167                         uint8_t size;
 168                         uint8_t horiz_pre;
 169                         uint8_t vert_pre;
 170                         uint32_t latitude;
 171                         uint32_t longitude;
 172                         uint32_t altitude;
 173                 } loc;
 174
 175                 /* https://tools.ietf.org/html/rfc4255#section-3.1 */
 176                 struct {
 177                         uint8_t algorithm;
 178                         uint8_t fptype;
 179                         void *fingerprint;
 180                         size_t fingerprint_size;
 181                 } sshfp;
 182
 183                 /* http://tools.ietf.org/html/rfc4034#section-2.1 */
 184                 struct {
 185                         uint16_t flags;
 186                         uint8_t protocol;
 187                         uint8_t algorithm;
 188                         void* key;
 189                         size_t key_size;
 190                 } dnskey;
 191
 192                 /* http://tools.ietf.org/html/rfc4034#section-3.1 */
 193                 struct {
 194                         uint16_t type_covered;
 195                         uint8_t algorithm;
 196                         uint8_t labels;
 197                         uint32_t original_ttl;
 198                         uint32_t expiration;
 199                         uint32_t inception;
 200                         uint16_t key_tag;
 201                         char *signer;
 202                         void *signature;
 203                         size_t signature_size;
 204                 } rrsig;
 205
 206                 /* https://tools.ietf.org/html/rfc4034#section-4.1 */
 207                 struct {
 208                         char *next_domain_name;
 209                         Bitmap *types;
 210                 } nsec;
 211
 212                 /* https://tools.ietf.org/html/rfc4034#section-5.1 */
 213                 struct {
 214                         uint16_t key_tag;
 215                         uint8_t algorithm;
 216                         uint8_t digest_type;
 217                         void *digest;
 218                         size_t digest_size;
 219                 } ds;
 220
 221                 struct {
 222                         uint8_t algorithm;
 223                         uint8_t flags;
 224                         uint16_t iterations;
 225                         void *salt;
 226                         size_t salt_size;
 227                         void *next_hashed_name;
 228                         size_t next_hashed_name_size;
 229                         Bitmap *types;
 230                 } nsec3;
 231
 232                 /* https://tools.ietf.org/html/draft-ietf-dane-protocol-23 */
 233                 struct {
 234                         uint8_t cert_usage;
 235                         uint8_t selector;
 236                         uint8_t matching_type;
 237                         void *data;
 238                         size_t data_size;
 239                 } tlsa;
 240
 241                 /* https://tools.ietf.org/html/rfc6844 */
 242                 struct {
 243                         uint8_t flags;
 244                         char *tag;
 245                         void *value;
 246                         size_t value_size;
 247                 } caa;
 248         };
 249 };
 250
 251 static inline const void* DNS_RESOURCE_RECORD_RDATA(DnsResourceRecord *rr) {
 252         if (!rr)
 253                 return NULL;
 254
 255         if (!rr->wire_format)
 256                 return NULL;
 257
 258         assert(rr->wire_format_rdata_offset <= rr->wire_format_size);
 259         return (uint8_t*) rr->wire_format + rr->wire_format_rdata_offset;
 260 }
 261
 262 static inline size_t DNS_RESOURCE_RECORD_RDATA_SIZE(DnsResourceRecord *rr) {
 263         if (!rr)
 264                 return 0;
 265         if (!rr->wire_format)
 266                 return 0;
 267
 268         assert(rr->wire_format_rdata_offset <= rr->wire_format_size);
 269         return rr->wire_format_size - rr->wire_format_rdata_offset;
 270 }
 271
 272 static inline uint8_t DNS_RESOURCE_RECORD_OPT_VERSION_SUPPORTED(DnsResourceRecord *rr) {
 273         assert(rr);
 274         assert(rr->key->type == DNS_TYPE_OPT);
 275
 276         return ((rr->ttl >> 16) & 0xFF) == 0;
 277 }
 278
 279 DnsResourceKey* dns_resource_key_new(uint16_t class, uint16_t type, const char *name);
 280 DnsResourceKey* dns_resource_key_new_redirect(const DnsResourceKey *key, const DnsResourceRecord *cname);
 281 int dns_resource_key_new_append_suffix(DnsResourceKey **ret, DnsResourceKey *key, char *name);
 282 DnsResourceKey* dns_resource_key_new_consume(uint16_t class, uint16_t type, char *name);
 283 DnsResourceKey* dns_resource_key_ref(DnsResourceKey *key);
 284 DnsResourceKey* dns_resource_key_unref(DnsResourceKey *key);
 285 const char* dns_resource_key_name(const DnsResourceKey *key);
 286 bool dns_resource_key_is_address(const DnsResourceKey *key);
 287 bool dns_resource_key_is_dnssd_ptr(const DnsResourceKey *key);
 288 int dns_resource_key_equal(const DnsResourceKey *a, const DnsResourceKey *b);
 289 int dns_resource_key_match_rr(const DnsResourceKey *key, DnsResourceRecord *rr, const char *search_domain);
 290 int dns_resource_key_match_cname_or_dname(const DnsResourceKey *key, const DnsResourceKey *cname, const char *search_domain);
 291 int dns_resource_key_match_soa(const DnsResourceKey *key, const DnsResourceKey *soa);
 292
 293 /* _DNS_{CLASS,TYPE}_STRING_MAX include one byte for NUL, which we use for space instead below.
 294  * DNS_HOSTNAME_MAX does not include the NUL byte, so we need to add 1. */
 295 #define DNS_RESOURCE_KEY_STRING_MAX (_DNS_CLASS_STRING_MAX + _DNS_TYPE_STRING_MAX + DNS_HOSTNAME_MAX + 1)
 296
 297 char* dns_resource_key_to_string(const DnsResourceKey *key, char *buf, size_t buf_size);
 298 ssize_t dns_resource_record_payload(DnsResourceRecord *rr, void **out);
 299
 300 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceKey*, dns_resource_key_unref);
 301
 302 static inline bool dns_key_is_shared(const DnsResourceKey *key) {
 303         return IN_SET(key->type, DNS_TYPE_PTR);
 304 }
 305
 306 bool dns_resource_key_reduce(DnsResourceKey **a, DnsResourceKey **b);
 307
 308 DnsResourceRecord* dns_resource_record_new(DnsResourceKey *key);
 309 DnsResourceRecord* dns_resource_record_new_full(uint16_t class, uint16_t type, const char *name);
 310 DnsResourceRecord* dns_resource_record_ref(DnsResourceRecord *rr);
 311 DnsResourceRecord* dns_resource_record_unref(DnsResourceRecord *rr);
 312 int dns_resource_record_new_reverse(DnsResourceRecord **ret, int family, const union in_addr_union *address, const char *name);
 313 int dns_resource_record_new_address(DnsResourceRecord **ret, int family, const union in_addr_union *address, const char *name);
 314 int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecord *b);
 315 const char* dns_resource_record_to_string(DnsResourceRecord *rr);
 316 DnsResourceRecord *dns_resource_record_copy(DnsResourceRecord *rr);
 317 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceRecord*, dns_resource_record_unref);
 318
 319 int dns_resource_record_to_wire_format(DnsResourceRecord *rr, bool canonical);
 320
 321 int dns_resource_record_signer(DnsResourceRecord *rr, const char **ret);
 322 int dns_resource_record_source(DnsResourceRecord *rr, const char **ret);
 323 int dns_resource_record_is_signer(DnsResourceRecord *rr, const char *zone);
 324 int dns_resource_record_is_synthetic(DnsResourceRecord *rr);
 325
 326 int dns_resource_record_clamp_ttl(DnsResourceRecord **rr, uint32_t max_ttl);
 327
 328 DnsTxtItem *dns_txt_item_free_all(DnsTxtItem *i);
 329 bool dns_txt_item_equal(DnsTxtItem *a, DnsTxtItem *b);
 330 DnsTxtItem *dns_txt_item_copy(DnsTxtItem *i);
 331 int dns_txt_item_new_empty(DnsTxtItem **ret);
 332
 333 void dns_resource_record_hash_func(const void *i, struct siphash *state);
 334
 335 extern const struct hash_ops dns_resource_key_hash_ops;
 336 extern const struct hash_ops dns_resource_record_hash_ops;
 337
 338 int dnssec_algorithm_to_string_alloc(int i, char **ret);
 339 int dnssec_algorithm_from_string(const char *s) _pure_;
 340
 341 int dnssec_digest_to_string_alloc(int i, char **ret);
 342 int dnssec_digest_from_string(const char *s) _pure_;