src/resolve/resolved-dns-rr.h

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2 #pragma once
   3
   4 #include <netinet/in.h>
   5
   6 #include "bitmap.h"
   7 #include "dns-def.h"
   8 #include "dns-type.h"
   9 #include "hashmap.h"
  10 #include "in-addr-util.h"
  11 #include "list.h"
  12 #include "string-util.h"
  13 #include "time-util.h"
  14
  15 typedef struct DnsResourceKey DnsResourceKey;
  16 typedef struct DnsResourceRecord DnsResourceRecord;
  17 typedef struct DnsTxtItem DnsTxtItem;
  18
  19 /* DNSKEY RR flags */
  20 #define DNSKEY_FLAG_SEP            (UINT16_C(1) << 0)
  21 #define DNSKEY_FLAG_REVOKE         (UINT16_C(1) << 7)
  22 #define DNSKEY_FLAG_ZONE_KEY       (UINT16_C(1) << 8)
  23
  24 /* mDNS RR flags */
  25 #define MDNS_RR_CACHE_FLUSH_OR_QU  (UINT16_C(1) << 15)
  26
  27 /* DNSSEC algorithm identifiers, see
  28  * http://tools.ietf.org/html/rfc4034#appendix-A.1 and
  29  * https://www.iana.org/assignments/dns-sec-alg-numbers/dns-sec-alg-numbers.xhtml */
  30 enum {
  31         DNSSEC_ALGORITHM_RSAMD5 = 1,
  32         DNSSEC_ALGORITHM_DH,
  33         DNSSEC_ALGORITHM_DSA,
  34         DNSSEC_ALGORITHM_ECC,
  35         DNSSEC_ALGORITHM_RSASHA1,
  36         DNSSEC_ALGORITHM_DSA_NSEC3_SHA1,
  37         DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1,
  38         DNSSEC_ALGORITHM_RSASHA256 = 8,        /* RFC 5702 */
  39         DNSSEC_ALGORITHM_RSASHA512 = 10,       /* RFC 5702 */
  40         DNSSEC_ALGORITHM_ECC_GOST = 12,        /* RFC 5933 */
  41         DNSSEC_ALGORITHM_ECDSAP256SHA256 = 13, /* RFC 6605 */
  42         DNSSEC_ALGORITHM_ECDSAP384SHA384 = 14, /* RFC 6605 */
  43         DNSSEC_ALGORITHM_ED25519 = 15,         /* RFC 8080 */
  44         DNSSEC_ALGORITHM_ED448 = 16,           /* RFC 8080 */
  45         DNSSEC_ALGORITHM_INDIRECT = 252,
  46         DNSSEC_ALGORITHM_PRIVATEDNS,
  47         DNSSEC_ALGORITHM_PRIVATEOID,
  48         _DNSSEC_ALGORITHM_MAX_DEFINED
  49 };
  50
  51 /* DNSSEC digest identifiers, see
  52  * https://www.iana.org/assignments/ds-rr-types/ds-rr-types.xhtml */
  53 enum {
  54         DNSSEC_DIGEST_SHA1 = 1,
  55         DNSSEC_DIGEST_SHA256 = 2,              /* RFC 4509 */
  56         DNSSEC_DIGEST_GOST_R_34_11_94 = 3,     /* RFC 5933 */
  57         DNSSEC_DIGEST_SHA384 = 4,              /* RFC 6605 */
  58         _DNSSEC_DIGEST_MAX_DEFINED
  59 };
  60
  61 /* DNSSEC NSEC3 hash algorithms, see
  62  * https://www.iana.org/assignments/dnssec-nsec3-parameters/dnssec-nsec3-parameters.xhtml */
  63 enum {
  64         NSEC3_ALGORITHM_SHA1 = 1,
  65         _NSEC3_ALGORITHM_MAX_DEFINED
  66 };
  67
  68 struct DnsResourceKey {
  69         unsigned n_ref; /* (unsigned -1) for const keys, see below */
  70         uint16_t class, type;
  71         char *_name; /* don't access directly, use dns_resource_key_name()! */
  72 };
  73
  74 /* Creates a temporary resource key. This is only useful to quickly
  75  * look up something, without allocating a full DnsResourceKey object
  76  * for it. Note that it is not OK to take references to this kind of
  77  * resource key object. */
  78 #define DNS_RESOURCE_KEY_CONST(c, t, n)                 \
  79         ((DnsResourceKey) {                             \
  80                 .n_ref = UINT_MAX,                      \
  81                 .class = c,                             \
  82                 .type = t,                              \
  83                 ._name = (char*) n,                     \
  84         })
  85
  86 struct DnsTxtItem {
  87         size_t length;
  88         LIST_FIELDS(DnsTxtItem, items);
  89         uint8_t data[];
  90 };
  91
  92 struct DnsResourceRecord {
  93         unsigned n_ref;
  94         uint32_t ttl;
  95         usec_t expiry; /* RRSIG signature expiry */
  96
  97         DnsResourceKey *key;
  98
  99         char *to_string;
 100
 101         /* How many labels to strip to determine "signer" of the RRSIG (aka, the zone). -1 if not signed. */
 102         uint8_t n_skip_labels_signer;
 103         /* How many labels to strip to determine "synthesizing source" of this RR, i.e. the wildcard's immediate parent. -1 if not signed. */
 104         uint8_t n_skip_labels_source;
 105
 106         bool unparsable;
 107         bool wire_format_canonical;
 108
 109         void *wire_format;
 110         size_t wire_format_size;
 111         size_t wire_format_rdata_offset;
 112
 113         union {
 114                 struct {
 115                         void *data;
 116                         size_t data_size;
 117                 } generic, opt;
 118
 119                 struct {
 120                         char *name;
 121                         uint16_t priority;
 122                         uint16_t weight;
 123                         uint16_t port;
 124                 } srv;
 125
 126                 struct {
 127                         char *name;
 128                 } ptr, ns, cname, dname;
 129
 130                 struct {
 131                         char *cpu;
 132                         char *os;
 133                 } hinfo;
 134
 135                 struct {
 136                         DnsTxtItem *items;
 137                 } txt, spf;
 138
 139                 struct {
 140                         struct in_addr in_addr;
 141                 } a;
 142
 143                 struct {
 144                         struct in6_addr in6_addr;
 145                 } aaaa;
 146
 147                 struct {
 148                         char *mname;
 149                         char *rname;
 150                         uint32_t serial;
 151                         uint32_t refresh;
 152                         uint32_t retry;
 153                         uint32_t expire;
 154                         uint32_t minimum;
 155                 } soa;
 156
 157                 struct {
 158                         char *exchange;
 159                         uint16_t priority;
 160                 } mx;
 161
 162                 /* https://tools.ietf.org/html/rfc1876 */
 163                 struct {
 164                         uint8_t version;
 165                         uint8_t size;
 166                         uint8_t horiz_pre;
 167                         uint8_t vert_pre;
 168                         uint32_t latitude;
 169                         uint32_t longitude;
 170                         uint32_t altitude;
 171                 } loc;
 172
 173                 /* https://tools.ietf.org/html/rfc4255#section-3.1 */
 174                 struct {
 175                         void *fingerprint;
 176                         size_t fingerprint_size;
 177
 178                         uint8_t algorithm;
 179                         uint8_t fptype;
 180                 } sshfp;
 181
 182                 /* http://tools.ietf.org/html/rfc4034#section-2.1 */
 183                 struct {
 184                         void* key;
 185                         size_t key_size;
 186
 187                         uint16_t flags;
 188                         uint8_t protocol;
 189                         uint8_t algorithm;
 190                 } dnskey;
 191
 192                 /* http://tools.ietf.org/html/rfc4034#section-3.1 */
 193                 struct {
 194                         char *signer;
 195                         void *signature;
 196                         size_t signature_size;
 197
 198                         uint16_t type_covered;
 199                         uint8_t algorithm;
 200                         uint8_t labels;
 201                         uint32_t original_ttl;
 202                         uint32_t expiration;
 203                         uint32_t inception;
 204                         uint16_t key_tag;
 205                 } rrsig;
 206
 207                 /* https://tools.ietf.org/html/rfc4034#section-4.1 */
 208                 struct {
 209                         char *next_domain_name;
 210                         Bitmap *types;
 211                 } nsec;
 212
 213                 /* https://tools.ietf.org/html/rfc4034#section-5.1 */
 214                 struct {
 215                         void *digest;
 216                         size_t digest_size;
 217
 218                         uint16_t key_tag;
 219                         uint8_t algorithm;
 220                         uint8_t digest_type;
 221                 } ds;
 222
 223                 struct {
 224                         Bitmap *types;
 225                         void *salt;
 226                         size_t salt_size;
 227                         void *next_hashed_name;
 228                         size_t next_hashed_name_size;
 229
 230                         uint8_t algorithm;
 231                         uint8_t flags;
 232                         uint16_t iterations;
 233                 } nsec3;
 234
 235                 /* https://tools.ietf.org/html/draft-ietf-dane-protocol-23 */
 236                 struct {
 237                         void *data;
 238                         size_t data_size;
 239
 240                         uint8_t cert_usage;
 241                         uint8_t selector;
 242                         uint8_t matching_type;
 243                 } tlsa;
 244
 245                 /* https://tools.ietf.org/html/rfc6844 */
 246                 struct {
 247                         char *tag;
 248                         void *value;
 249                         size_t value_size;
 250
 251                         uint8_t flags;
 252                 } caa;
 253         };
 254
 255         /* Note: fields should be ordered to minimize alignment gaps. Use pahole! */
 256 };
 257
 258 /* We use uint8_t for label counts above, and UINT8_MAX/-1 has special meaning. */
 259 assert_cc(DNS_N_LABELS_MAX < UINT8_MAX);
 260
 261 static inline const void* DNS_RESOURCE_RECORD_RDATA(const DnsResourceRecord *rr) {
 262         if (!rr)
 263                 return NULL;
 264
 265         if (!rr->wire_format)
 266                 return NULL;
 267
 268         assert(rr->wire_format_rdata_offset <= rr->wire_format_size);
 269         return (uint8_t*) rr->wire_format + rr->wire_format_rdata_offset;
 270 }
 271
 272 static inline size_t DNS_RESOURCE_RECORD_RDATA_SIZE(const DnsResourceRecord *rr) {
 273         if (!rr)
 274                 return 0;
 275         if (!rr->wire_format)
 276                 return 0;
 277
 278         assert(rr->wire_format_rdata_offset <= rr->wire_format_size);
 279         return rr->wire_format_size - rr->wire_format_rdata_offset;
 280 }
 281
 282 static inline uint8_t DNS_RESOURCE_RECORD_OPT_VERSION_SUPPORTED(const DnsResourceRecord *rr) {
 283         assert(rr);
 284         assert(rr->key->type == DNS_TYPE_OPT);
 285
 286         return ((rr->ttl >> 16) & 0xFF) == 0;
 287 }
 288
 289 DnsResourceKey* dns_resource_key_new(uint16_t class, uint16_t type, const char *name);
 290 DnsResourceKey* dns_resource_key_new_redirect(const DnsResourceKey *key, const DnsResourceRecord *cname);
 291 int dns_resource_key_new_append_suffix(DnsResourceKey **ret, DnsResourceKey *key, char *name);
 292 DnsResourceKey* dns_resource_key_new_consume(uint16_t class, uint16_t type, char *name);
 293 DnsResourceKey* dns_resource_key_ref(DnsResourceKey *key);
 294 DnsResourceKey* dns_resource_key_unref(DnsResourceKey *key);
 295 const char* dns_resource_key_name(const DnsResourceKey *key);
 296 bool dns_resource_key_is_address(const DnsResourceKey *key);
 297 bool dns_resource_key_is_dnssd_ptr(const DnsResourceKey *key);
 298 int dns_resource_key_equal(const DnsResourceKey *a, const DnsResourceKey *b);
 299 int dns_resource_key_match_rr(const DnsResourceKey *key, DnsResourceRecord *rr, const char *search_domain);
 300 int dns_resource_key_match_cname_or_dname(const DnsResourceKey *key, const DnsResourceKey *cname, const char *search_domain);
 301 int dns_resource_key_match_soa(const DnsResourceKey *key, const DnsResourceKey *soa);
 302
 303 /* _DNS_{CLASS,TYPE}_STRING_MAX include one byte for NUL, which we use for space instead below.
 304  * DNS_HOSTNAME_MAX does not include the NUL byte, so we need to add 1. */
 305 #define DNS_RESOURCE_KEY_STRING_MAX (_DNS_CLASS_STRING_MAX + _DNS_TYPE_STRING_MAX + DNS_HOSTNAME_MAX + 1)
 306
 307 char* dns_resource_key_to_string(const DnsResourceKey *key, char *buf, size_t buf_size);
 308 ssize_t dns_resource_record_payload(DnsResourceRecord *rr, void **out);
 309
 310 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceKey*, dns_resource_key_unref);
 311
 312 static inline bool dns_key_is_shared(const DnsResourceKey *key) {
 313         return IN_SET(key->type, DNS_TYPE_PTR);
 314 }
 315
 316 bool dns_resource_key_reduce(DnsResourceKey **a, DnsResourceKey **b);
 317
 318 DnsResourceRecord* dns_resource_record_new(DnsResourceKey *key);
 319 DnsResourceRecord* dns_resource_record_new_full(uint16_t class, uint16_t type, const char *name);
 320 DnsResourceRecord* dns_resource_record_ref(DnsResourceRecord *rr);
 321 DnsResourceRecord* dns_resource_record_unref(DnsResourceRecord *rr);
 322
 323 #define DNS_RR_REPLACE(a, b)                    \
 324         do {                                    \
 325                 typeof(a)* _a = &(a);           \
 326                 typeof(b) _b = (b);             \
 327                 dns_resource_record_unref(*_a); \
 328                 *_a = _b;                       \
 329         } while(0)
 330
 331 int dns_resource_record_new_reverse(DnsResourceRecord **ret, int family, const union in_addr_union *address, const char *name);
 332 int dns_resource_record_new_address(DnsResourceRecord **ret, int family, const union in_addr_union *address, const char *name);
 333 int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecord *b);
 334 int dns_resource_record_payload_equal(const DnsResourceRecord *a, const DnsResourceRecord *b);
 335
 336 const char* dns_resource_record_to_string(DnsResourceRecord *rr);
 337 DnsResourceRecord *dns_resource_record_copy(DnsResourceRecord *rr);
 338 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceRecord*, dns_resource_record_unref);
 339
 340 int dns_resource_record_to_wire_format(DnsResourceRecord *rr, bool canonical);
 341
 342 int dns_resource_record_signer(DnsResourceRecord *rr, const char **ret);
 343 int dns_resource_record_source(DnsResourceRecord *rr, const char **ret);
 344 int dns_resource_record_is_signer(DnsResourceRecord *rr, const char *zone);
 345 int dns_resource_record_is_synthetic(DnsResourceRecord *rr);
 346
 347 int dns_resource_record_clamp_ttl(DnsResourceRecord **rr, uint32_t max_ttl);
 348
 349 bool dns_resource_record_is_link_local_address(DnsResourceRecord *rr);
 350
 351 int dns_resource_record_get_cname_target(DnsResourceKey *key, DnsResourceRecord *cname, char **ret);
 352
 353 DnsTxtItem *dns_txt_item_free_all(DnsTxtItem *i);
 354 bool dns_txt_item_equal(DnsTxtItem *a, DnsTxtItem *b);
 355 DnsTxtItem *dns_txt_item_copy(DnsTxtItem *i);
 356 int dns_txt_item_new_empty(DnsTxtItem **ret);
 357
 358 void dns_resource_record_hash_func(const DnsResourceRecord *i, struct siphash *state);
 359 int dns_resource_record_compare_func(const DnsResourceRecord *x, const DnsResourceRecord *y);
 360
 361 extern const struct hash_ops dns_resource_key_hash_ops;
 362 extern const struct hash_ops dns_resource_record_hash_ops;
 363
 364 int dnssec_algorithm_to_string_alloc(int i, char **ret);
 365 int dnssec_algorithm_from_string(const char *s) _pure_;
 366
 367 int dnssec_digest_to_string_alloc(int i, char **ret);
 368 int dnssec_digest_from_string(const char *s) _pure_;