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Commit | Line | Data |
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db9ecf05 | 1 | /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
2b442ac8 | 2 | |
2b442ac8 LP |
3 | #include "alloc-util.h" |
4 | #include "dns-domain.h" | |
cb9eeb06 MCO |
5 | #include "fd-util.h" |
6 | #include "fileio.h" | |
91e023d8 | 7 | #include "gcrypt-util.h" |
72667f08 | 8 | #include "hexdecoct.h" |
0a970718 | 9 | #include "memory-util.h" |
2b442ac8 LP |
10 | #include "resolved-dns-dnssec.h" |
11 | #include "resolved-dns-packet.h" | |
760877e9 | 12 | #include "sort-util.h" |
24710c48 | 13 | #include "string-table.h" |
2b442ac8 | 14 | |
2b442ac8 LP |
15 | #define VERIFY_RRS_MAX 256 |
16 | #define MAX_KEY_SIZE (32*1024) | |
17 | ||
896c5672 LP |
18 | /* Permit a maximum clock skew of 1h 10min. This should be enough to deal with DST confusion */ |
19 | #define SKEW_MAX (1*USEC_PER_HOUR + 10*USEC_PER_MINUTE) | |
20 | ||
3a33c81b LP |
21 | /* Maximum number of NSEC3 iterations we'll do. RFC5155 says 2500 shall be the maximum useful value */ |
22 | #define NSEC3_ITERATIONS_MAX 2500 | |
a8f158b9 | 23 | |
2b442ac8 LP |
24 | /* |
25 | * The DNSSEC Chain of trust: | |
26 | * | |
27 | * Normal RRs are protected via RRSIG RRs in combination with DNSKEY RRs, all in the same zone | |
28 | * DNSKEY RRs are either protected like normal RRs, or via a DS from a zone "higher" up the tree | |
29 | * DS RRs are protected like normal RRs | |
30 | * | |
31 | * Example chain: | |
32 | * Normal RR → RRSIG/DNSKEY+ → DS → RRSIG/DNSKEY+ → DS → ... → DS → RRSIG/DNSKEY+ → DS | |
33 | */ | |
34 | ||
0c857028 | 35 | uint16_t dnssec_keytag(DnsResourceRecord *dnskey, bool mask_revoke) { |
2b442ac8 | 36 | const uint8_t *p; |
0c857028 | 37 | uint32_t sum, f; |
2b442ac8 LP |
38 | size_t i; |
39 | ||
40 | /* The algorithm from RFC 4034, Appendix B. */ | |
41 | ||
42 | assert(dnskey); | |
43 | assert(dnskey->key->type == DNS_TYPE_DNSKEY); | |
44 | ||
0c857028 LP |
45 | f = (uint32_t) dnskey->dnskey.flags; |
46 | ||
47 | if (mask_revoke) | |
48 | f &= ~DNSKEY_FLAG_REVOKE; | |
49 | ||
50 | sum = f + ((((uint32_t) dnskey->dnskey.protocol) << 8) + (uint32_t) dnskey->dnskey.algorithm); | |
2b442ac8 LP |
51 | |
52 | p = dnskey->dnskey.key; | |
53 | ||
54 | for (i = 0; i < dnskey->dnskey.key_size; i++) | |
55 | sum += (i & 1) == 0 ? (uint32_t) p[i] << 8 : (uint32_t) p[i]; | |
56 | ||
57 | sum += (sum >> 16) & UINT32_C(0xFFFF); | |
58 | ||
59 | return sum & UINT32_C(0xFFFF); | |
60 | } | |
61 | ||
349cc4a5 | 62 | #if HAVE_GCRYPT |
47091522 | 63 | |
93bab288 YW |
64 | static int rr_compare(DnsResourceRecord * const *a, DnsResourceRecord * const *b) { |
65 | const DnsResourceRecord *x = *a, *y = *b; | |
2b442ac8 LP |
66 | size_t m; |
67 | int r; | |
68 | ||
69 | /* Let's order the RRs according to RFC 4034, Section 6.3 */ | |
70 | ||
71 | assert(x); | |
93bab288 | 72 | assert(x->wire_format); |
2b442ac8 | 73 | assert(y); |
93bab288 | 74 | assert(y->wire_format); |
2b442ac8 | 75 | |
93bab288 | 76 | m = MIN(DNS_RESOURCE_RECORD_RDATA_SIZE(x), DNS_RESOURCE_RECORD_RDATA_SIZE(y)); |
2b442ac8 | 77 | |
93bab288 | 78 | r = memcmp(DNS_RESOURCE_RECORD_RDATA(x), DNS_RESOURCE_RECORD_RDATA(y), m); |
2b442ac8 LP |
79 | if (r != 0) |
80 | return r; | |
81 | ||
93bab288 | 82 | return CMP(DNS_RESOURCE_RECORD_RDATA_SIZE(x), DNS_RESOURCE_RECORD_RDATA_SIZE(y)); |
2b442ac8 LP |
83 | } |
84 | ||
ea3a892f | 85 | static int dnssec_rsa_verify_raw( |
2b442ac8 LP |
86 | const char *hash_algorithm, |
87 | const void *signature, size_t signature_size, | |
88 | const void *data, size_t data_size, | |
89 | const void *exponent, size_t exponent_size, | |
90 | const void *modulus, size_t modulus_size) { | |
91 | ||
92 | gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; | |
93 | gcry_mpi_t n = NULL, e = NULL, s = NULL; | |
94 | gcry_error_t ge; | |
95 | int r; | |
96 | ||
97 | assert(hash_algorithm); | |
98 | ||
99 | ge = gcry_mpi_scan(&s, GCRYMPI_FMT_USG, signature, signature_size, NULL); | |
100 | if (ge != 0) { | |
101 | r = -EIO; | |
102 | goto finish; | |
103 | } | |
104 | ||
105 | ge = gcry_mpi_scan(&e, GCRYMPI_FMT_USG, exponent, exponent_size, NULL); | |
106 | if (ge != 0) { | |
107 | r = -EIO; | |
108 | goto finish; | |
109 | } | |
110 | ||
111 | ge = gcry_mpi_scan(&n, GCRYMPI_FMT_USG, modulus, modulus_size, NULL); | |
112 | if (ge != 0) { | |
113 | r = -EIO; | |
114 | goto finish; | |
115 | } | |
116 | ||
117 | ge = gcry_sexp_build(&signature_sexp, | |
118 | NULL, | |
119 | "(sig-val (rsa (s %m)))", | |
120 | s); | |
121 | ||
122 | if (ge != 0) { | |
123 | r = -EIO; | |
124 | goto finish; | |
125 | } | |
126 | ||
127 | ge = gcry_sexp_build(&data_sexp, | |
128 | NULL, | |
129 | "(data (flags pkcs1) (hash %s %b))", | |
130 | hash_algorithm, | |
131 | (int) data_size, | |
132 | data); | |
133 | if (ge != 0) { | |
134 | r = -EIO; | |
135 | goto finish; | |
136 | } | |
137 | ||
138 | ge = gcry_sexp_build(&public_key_sexp, | |
139 | NULL, | |
140 | "(public-key (rsa (n %m) (e %m)))", | |
141 | n, | |
142 | e); | |
143 | if (ge != 0) { | |
144 | r = -EIO; | |
145 | goto finish; | |
146 | } | |
147 | ||
148 | ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp); | |
d12bf2bd | 149 | if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE) |
2b442ac8 | 150 | r = 0; |
d12bf2bd LP |
151 | else if (ge != 0) { |
152 | log_debug("RSA signature check failed: %s", gpg_strerror(ge)); | |
2b442ac8 | 153 | r = -EIO; |
d12bf2bd | 154 | } else |
2b442ac8 LP |
155 | r = 1; |
156 | ||
157 | finish: | |
158 | if (e) | |
159 | gcry_mpi_release(e); | |
160 | if (n) | |
161 | gcry_mpi_release(n); | |
162 | if (s) | |
163 | gcry_mpi_release(s); | |
164 | ||
165 | if (public_key_sexp) | |
166 | gcry_sexp_release(public_key_sexp); | |
167 | if (signature_sexp) | |
168 | gcry_sexp_release(signature_sexp); | |
169 | if (data_sexp) | |
170 | gcry_sexp_release(data_sexp); | |
171 | ||
172 | return r; | |
173 | } | |
174 | ||
ea3a892f LP |
175 | static int dnssec_rsa_verify( |
176 | const char *hash_algorithm, | |
177 | const void *hash, size_t hash_size, | |
178 | DnsResourceRecord *rrsig, | |
179 | DnsResourceRecord *dnskey) { | |
180 | ||
181 | size_t exponent_size, modulus_size; | |
182 | void *exponent, *modulus; | |
183 | ||
184 | assert(hash_algorithm); | |
185 | assert(hash); | |
186 | assert(hash_size > 0); | |
187 | assert(rrsig); | |
188 | assert(dnskey); | |
189 | ||
190 | if (*(uint8_t*) dnskey->dnskey.key == 0) { | |
191 | /* exponent is > 255 bytes long */ | |
192 | ||
193 | exponent = (uint8_t*) dnskey->dnskey.key + 3; | |
194 | exponent_size = | |
ac04adbe TG |
195 | ((size_t) (((uint8_t*) dnskey->dnskey.key)[1]) << 8) | |
196 | ((size_t) ((uint8_t*) dnskey->dnskey.key)[2]); | |
ea3a892f LP |
197 | |
198 | if (exponent_size < 256) | |
199 | return -EINVAL; | |
200 | ||
201 | if (3 + exponent_size >= dnskey->dnskey.key_size) | |
202 | return -EINVAL; | |
203 | ||
204 | modulus = (uint8_t*) dnskey->dnskey.key + 3 + exponent_size; | |
205 | modulus_size = dnskey->dnskey.key_size - 3 - exponent_size; | |
206 | ||
207 | } else { | |
208 | /* exponent is <= 255 bytes long */ | |
209 | ||
210 | exponent = (uint8_t*) dnskey->dnskey.key + 1; | |
211 | exponent_size = (size_t) ((uint8_t*) dnskey->dnskey.key)[0]; | |
212 | ||
213 | if (exponent_size <= 0) | |
214 | return -EINVAL; | |
215 | ||
216 | if (1 + exponent_size >= dnskey->dnskey.key_size) | |
217 | return -EINVAL; | |
218 | ||
219 | modulus = (uint8_t*) dnskey->dnskey.key + 1 + exponent_size; | |
220 | modulus_size = dnskey->dnskey.key_size - 1 - exponent_size; | |
221 | } | |
222 | ||
223 | return dnssec_rsa_verify_raw( | |
224 | hash_algorithm, | |
225 | rrsig->rrsig.signature, rrsig->rrsig.signature_size, | |
226 | hash, hash_size, | |
227 | exponent, exponent_size, | |
228 | modulus, modulus_size); | |
229 | } | |
230 | ||
e0240c64 LP |
231 | static int dnssec_ecdsa_verify_raw( |
232 | const char *hash_algorithm, | |
233 | const char *curve, | |
234 | const void *signature_r, size_t signature_r_size, | |
235 | const void *signature_s, size_t signature_s_size, | |
236 | const void *data, size_t data_size, | |
237 | const void *key, size_t key_size) { | |
238 | ||
239 | gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; | |
240 | gcry_mpi_t q = NULL, r = NULL, s = NULL; | |
241 | gcry_error_t ge; | |
242 | int k; | |
243 | ||
244 | assert(hash_algorithm); | |
245 | ||
246 | ge = gcry_mpi_scan(&r, GCRYMPI_FMT_USG, signature_r, signature_r_size, NULL); | |
247 | if (ge != 0) { | |
248 | k = -EIO; | |
249 | goto finish; | |
250 | } | |
251 | ||
252 | ge = gcry_mpi_scan(&s, GCRYMPI_FMT_USG, signature_s, signature_s_size, NULL); | |
253 | if (ge != 0) { | |
254 | k = -EIO; | |
255 | goto finish; | |
256 | } | |
257 | ||
258 | ge = gcry_mpi_scan(&q, GCRYMPI_FMT_USG, key, key_size, NULL); | |
259 | if (ge != 0) { | |
260 | k = -EIO; | |
261 | goto finish; | |
262 | } | |
263 | ||
264 | ge = gcry_sexp_build(&signature_sexp, | |
265 | NULL, | |
266 | "(sig-val (ecdsa (r %m) (s %m)))", | |
267 | r, | |
268 | s); | |
269 | if (ge != 0) { | |
270 | k = -EIO; | |
271 | goto finish; | |
272 | } | |
273 | ||
274 | ge = gcry_sexp_build(&data_sexp, | |
275 | NULL, | |
276 | "(data (flags rfc6979) (hash %s %b))", | |
277 | hash_algorithm, | |
278 | (int) data_size, | |
279 | data); | |
280 | if (ge != 0) { | |
281 | k = -EIO; | |
282 | goto finish; | |
283 | } | |
284 | ||
285 | ge = gcry_sexp_build(&public_key_sexp, | |
286 | NULL, | |
287 | "(public-key (ecc (curve %s) (q %m)))", | |
288 | curve, | |
289 | q); | |
290 | if (ge != 0) { | |
291 | k = -EIO; | |
292 | goto finish; | |
293 | } | |
294 | ||
295 | ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp); | |
296 | if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE) | |
297 | k = 0; | |
298 | else if (ge != 0) { | |
299 | log_debug("ECDSA signature check failed: %s", gpg_strerror(ge)); | |
300 | k = -EIO; | |
301 | } else | |
302 | k = 1; | |
303 | finish: | |
304 | if (r) | |
305 | gcry_mpi_release(r); | |
306 | if (s) | |
307 | gcry_mpi_release(s); | |
308 | if (q) | |
309 | gcry_mpi_release(q); | |
310 | ||
311 | if (public_key_sexp) | |
312 | gcry_sexp_release(public_key_sexp); | |
313 | if (signature_sexp) | |
314 | gcry_sexp_release(signature_sexp); | |
315 | if (data_sexp) | |
316 | gcry_sexp_release(data_sexp); | |
317 | ||
318 | return k; | |
319 | } | |
320 | ||
321 | static int dnssec_ecdsa_verify( | |
322 | const char *hash_algorithm, | |
323 | int algorithm, | |
324 | const void *hash, size_t hash_size, | |
325 | DnsResourceRecord *rrsig, | |
326 | DnsResourceRecord *dnskey) { | |
327 | ||
328 | const char *curve; | |
329 | size_t key_size; | |
330 | uint8_t *q; | |
331 | ||
332 | assert(hash); | |
333 | assert(hash_size); | |
334 | assert(rrsig); | |
335 | assert(dnskey); | |
336 | ||
337 | if (algorithm == DNSSEC_ALGORITHM_ECDSAP256SHA256) { | |
338 | key_size = 32; | |
339 | curve = "NIST P-256"; | |
340 | } else if (algorithm == DNSSEC_ALGORITHM_ECDSAP384SHA384) { | |
341 | key_size = 48; | |
342 | curve = "NIST P-384"; | |
343 | } else | |
344 | return -EOPNOTSUPP; | |
345 | ||
346 | if (dnskey->dnskey.key_size != key_size * 2) | |
347 | return -EINVAL; | |
348 | ||
349 | if (rrsig->rrsig.signature_size != key_size * 2) | |
350 | return -EINVAL; | |
351 | ||
6e9417f5 | 352 | q = newa(uint8_t, key_size*2 + 1); |
e0240c64 LP |
353 | q[0] = 0x04; /* Prepend 0x04 to indicate an uncompressed key */ |
354 | memcpy(q+1, dnskey->dnskey.key, key_size*2); | |
355 | ||
356 | return dnssec_ecdsa_verify_raw( | |
357 | hash_algorithm, | |
358 | curve, | |
359 | rrsig->rrsig.signature, key_size, | |
360 | (uint8_t*) rrsig->rrsig.signature + key_size, key_size, | |
361 | hash, hash_size, | |
362 | q, key_size*2+1); | |
363 | } | |
364 | ||
cb9eeb06 MCO |
365 | #if GCRYPT_VERSION_NUMBER >= 0x010600 |
366 | static int dnssec_eddsa_verify_raw( | |
367 | const char *curve, | |
368 | const void *signature_r, size_t signature_r_size, | |
369 | const void *signature_s, size_t signature_s_size, | |
370 | const void *data, size_t data_size, | |
371 | const void *key, size_t key_size) { | |
372 | ||
373 | gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; | |
374 | gcry_error_t ge; | |
375 | int k; | |
376 | ||
377 | ge = gcry_sexp_build(&signature_sexp, | |
378 | NULL, | |
379 | "(sig-val (eddsa (r %b) (s %b)))", | |
380 | (int) signature_r_size, | |
381 | signature_r, | |
382 | (int) signature_s_size, | |
383 | signature_s); | |
384 | if (ge != 0) { | |
385 | k = -EIO; | |
386 | goto finish; | |
387 | } | |
388 | ||
389 | ge = gcry_sexp_build(&data_sexp, | |
390 | NULL, | |
391 | "(data (flags eddsa) (hash-algo sha512) (value %b))", | |
392 | (int) data_size, | |
393 | data); | |
394 | if (ge != 0) { | |
395 | k = -EIO; | |
396 | goto finish; | |
397 | } | |
398 | ||
399 | ge = gcry_sexp_build(&public_key_sexp, | |
400 | NULL, | |
401 | "(public-key (ecc (curve %s) (flags eddsa) (q %b)))", | |
402 | curve, | |
403 | (int) key_size, | |
404 | key); | |
405 | if (ge != 0) { | |
406 | k = -EIO; | |
407 | goto finish; | |
408 | } | |
409 | ||
410 | ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp); | |
411 | if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE) | |
412 | k = 0; | |
413 | else if (ge != 0) { | |
414 | log_debug("EdDSA signature check failed: %s", gpg_strerror(ge)); | |
415 | k = -EIO; | |
416 | } else | |
417 | k = 1; | |
418 | finish: | |
419 | if (public_key_sexp) | |
420 | gcry_sexp_release(public_key_sexp); | |
421 | if (signature_sexp) | |
422 | gcry_sexp_release(signature_sexp); | |
423 | if (data_sexp) | |
424 | gcry_sexp_release(data_sexp); | |
425 | ||
426 | return k; | |
427 | } | |
428 | ||
429 | static int dnssec_eddsa_verify( | |
430 | int algorithm, | |
431 | const void *data, size_t data_size, | |
432 | DnsResourceRecord *rrsig, | |
433 | DnsResourceRecord *dnskey) { | |
434 | const char *curve; | |
435 | size_t key_size; | |
436 | ||
437 | if (algorithm == DNSSEC_ALGORITHM_ED25519) { | |
438 | curve = "Ed25519"; | |
439 | key_size = 32; | |
440 | } else | |
441 | return -EOPNOTSUPP; | |
442 | ||
443 | if (dnskey->dnskey.key_size != key_size) | |
444 | return -EINVAL; | |
445 | ||
446 | if (rrsig->rrsig.signature_size != key_size * 2) | |
447 | return -EINVAL; | |
448 | ||
449 | return dnssec_eddsa_verify_raw( | |
450 | curve, | |
451 | rrsig->rrsig.signature, key_size, | |
452 | (uint8_t*) rrsig->rrsig.signature + key_size, key_size, | |
453 | data, data_size, | |
454 | dnskey->dnskey.key, key_size); | |
455 | } | |
456 | #endif | |
457 | ||
2b442ac8 LP |
458 | static void md_add_uint8(gcry_md_hd_t md, uint8_t v) { |
459 | gcry_md_write(md, &v, sizeof(v)); | |
460 | } | |
461 | ||
462 | static void md_add_uint16(gcry_md_hd_t md, uint16_t v) { | |
463 | v = htobe16(v); | |
464 | gcry_md_write(md, &v, sizeof(v)); | |
465 | } | |
466 | ||
cb9eeb06 MCO |
467 | static void fwrite_uint8(FILE *fp, uint8_t v) { |
468 | fwrite(&v, sizeof(v), 1, fp); | |
469 | } | |
470 | ||
471 | static void fwrite_uint16(FILE *fp, uint16_t v) { | |
472 | v = htobe16(v); | |
473 | fwrite(&v, sizeof(v), 1, fp); | |
474 | } | |
475 | ||
476 | static void fwrite_uint32(FILE *fp, uint32_t v) { | |
2b442ac8 | 477 | v = htobe32(v); |
cb9eeb06 | 478 | fwrite(&v, sizeof(v), 1, fp); |
2b442ac8 LP |
479 | } |
480 | ||
97c67192 LP |
481 | static int dnssec_rrsig_prepare(DnsResourceRecord *rrsig) { |
482 | int n_key_labels, n_signer_labels; | |
483 | const char *name; | |
484 | int r; | |
485 | ||
486 | /* Checks whether the specified RRSIG RR is somewhat valid, and initializes the .n_skip_labels_source and | |
487 | * .n_skip_labels_signer fields so that we can use them later on. */ | |
488 | ||
489 | assert(rrsig); | |
490 | assert(rrsig->key->type == DNS_TYPE_RRSIG); | |
491 | ||
492 | /* Check if this RRSIG RR is already prepared */ | |
f5fbe71d | 493 | if (rrsig->n_skip_labels_source != UINT_MAX) |
97c67192 LP |
494 | return 0; |
495 | ||
496 | if (rrsig->rrsig.inception > rrsig->rrsig.expiration) | |
497 | return -EINVAL; | |
498 | ||
1c02e7ba | 499 | name = dns_resource_key_name(rrsig->key); |
97c67192 LP |
500 | |
501 | n_key_labels = dns_name_count_labels(name); | |
502 | if (n_key_labels < 0) | |
503 | return n_key_labels; | |
504 | if (rrsig->rrsig.labels > n_key_labels) | |
505 | return -EINVAL; | |
506 | ||
507 | n_signer_labels = dns_name_count_labels(rrsig->rrsig.signer); | |
508 | if (n_signer_labels < 0) | |
509 | return n_signer_labels; | |
510 | if (n_signer_labels > rrsig->rrsig.labels) | |
511 | return -EINVAL; | |
512 | ||
513 | r = dns_name_skip(name, n_key_labels - n_signer_labels, &name); | |
514 | if (r < 0) | |
515 | return r; | |
516 | if (r == 0) | |
517 | return -EINVAL; | |
518 | ||
519 | /* Check if the signer is really a suffix of us */ | |
520 | r = dns_name_equal(name, rrsig->rrsig.signer); | |
521 | if (r < 0) | |
522 | return r; | |
523 | if (r == 0) | |
524 | return -EINVAL; | |
525 | ||
526 | rrsig->n_skip_labels_source = n_key_labels - rrsig->rrsig.labels; | |
527 | rrsig->n_skip_labels_signer = n_key_labels - n_signer_labels; | |
528 | ||
529 | return 0; | |
530 | } | |
531 | ||
2a326321 LP |
532 | static int dnssec_rrsig_expired(DnsResourceRecord *rrsig, usec_t realtime) { |
533 | usec_t expiration, inception, skew; | |
534 | ||
535 | assert(rrsig); | |
536 | assert(rrsig->key->type == DNS_TYPE_RRSIG); | |
537 | ||
538 | if (realtime == USEC_INFINITY) | |
539 | realtime = now(CLOCK_REALTIME); | |
540 | ||
541 | expiration = rrsig->rrsig.expiration * USEC_PER_SEC; | |
542 | inception = rrsig->rrsig.inception * USEC_PER_SEC; | |
543 | ||
5ae5cd40 | 544 | /* Consider inverted validity intervals as expired */ |
2a326321 | 545 | if (inception > expiration) |
5ae5cd40 | 546 | return true; |
2a326321 | 547 | |
896c5672 LP |
548 | /* Permit a certain amount of clock skew of 10% of the valid |
549 | * time range. This takes inspiration from unbound's | |
550 | * resolver. */ | |
2a326321 | 551 | skew = (expiration - inception) / 10; |
896c5672 LP |
552 | if (skew > SKEW_MAX) |
553 | skew = SKEW_MAX; | |
2a326321 LP |
554 | |
555 | if (inception < skew) | |
556 | inception = 0; | |
557 | else | |
558 | inception -= skew; | |
559 | ||
560 | if (expiration + skew < expiration) | |
561 | expiration = USEC_INFINITY; | |
562 | else | |
563 | expiration += skew; | |
564 | ||
565 | return realtime < inception || realtime > expiration; | |
566 | } | |
567 | ||
ca994e85 | 568 | static int algorithm_to_gcrypt_md(uint8_t algorithm) { |
fbf1a66d | 569 | |
6af47493 LP |
570 | /* Translates a DNSSEC signature algorithm into a gcrypt |
571 | * digest identifier. | |
572 | * | |
573 | * Note that we implement all algorithms listed as "Must | |
574 | * implement" and "Recommended to Implement" in RFC6944. We | |
575 | * don't implement any algorithms that are listed as | |
576 | * "Optional" or "Must Not Implement". Specifically, we do not | |
577 | * implement RSAMD5, DSASHA1, DH, DSA-NSEC3-SHA1, and | |
578 | * GOST-ECC. */ | |
fbf1a66d LP |
579 | |
580 | switch (algorithm) { | |
581 | ||
582 | case DNSSEC_ALGORITHM_RSASHA1: | |
583 | case DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1: | |
584 | return GCRY_MD_SHA1; | |
585 | ||
586 | case DNSSEC_ALGORITHM_RSASHA256: | |
e0240c64 | 587 | case DNSSEC_ALGORITHM_ECDSAP256SHA256: |
fbf1a66d LP |
588 | return GCRY_MD_SHA256; |
589 | ||
e0240c64 LP |
590 | case DNSSEC_ALGORITHM_ECDSAP384SHA384: |
591 | return GCRY_MD_SHA384; | |
592 | ||
fbf1a66d LP |
593 | case DNSSEC_ALGORITHM_RSASHA512: |
594 | return GCRY_MD_SHA512; | |
595 | ||
596 | default: | |
597 | return -EOPNOTSUPP; | |
598 | } | |
599 | } | |
600 | ||
97c67192 LP |
601 | static void dnssec_fix_rrset_ttl( |
602 | DnsResourceRecord *list[], | |
603 | unsigned n, | |
604 | DnsResourceRecord *rrsig, | |
605 | usec_t realtime) { | |
606 | ||
607 | unsigned k; | |
608 | ||
609 | assert(list); | |
610 | assert(n > 0); | |
611 | assert(rrsig); | |
612 | ||
613 | for (k = 0; k < n; k++) { | |
614 | DnsResourceRecord *rr = list[k]; | |
615 | ||
616 | /* Pick the TTL as the minimum of the RR's TTL, the | |
617 | * RR's original TTL according to the RRSIG and the | |
618 | * RRSIG's own TTL, see RFC 4035, Section 5.3.3 */ | |
619 | rr->ttl = MIN3(rr->ttl, rrsig->rrsig.original_ttl, rrsig->ttl); | |
620 | rr->expiry = rrsig->rrsig.expiration * USEC_PER_SEC; | |
621 | ||
622 | /* Copy over information about the signer and wildcard source of synthesis */ | |
623 | rr->n_skip_labels_source = rrsig->n_skip_labels_source; | |
624 | rr->n_skip_labels_signer = rrsig->n_skip_labels_signer; | |
625 | } | |
626 | ||
627 | rrsig->expiry = rrsig->rrsig.expiration * USEC_PER_SEC; | |
628 | } | |
629 | ||
2a326321 LP |
630 | int dnssec_verify_rrset( |
631 | DnsAnswer *a, | |
0c857028 | 632 | const DnsResourceKey *key, |
2a326321 LP |
633 | DnsResourceRecord *rrsig, |
634 | DnsResourceRecord *dnskey, | |
547973de LP |
635 | usec_t realtime, |
636 | DnssecResult *result) { | |
2a326321 | 637 | |
5e55cde9 | 638 | uint8_t wire_format_name[DNS_WIRE_FORMAT_HOSTNAME_MAX]; |
2b442ac8 | 639 | DnsResourceRecord **list, *rr; |
588c53d0 | 640 | const char *source, *name; |
8530efc1 | 641 | _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL; |
ca994e85 | 642 | int r, md_algorithm; |
2b442ac8 | 643 | size_t k, n = 0; |
cb9eeb06 MCO |
644 | size_t sig_size = 0; |
645 | _cleanup_free_ char *sig_data = NULL; | |
646 | _cleanup_fclose_ FILE *f = NULL; | |
588c53d0 LP |
647 | size_t hash_size; |
648 | void *hash; | |
7715f91d | 649 | bool wildcard; |
2b442ac8 LP |
650 | |
651 | assert(key); | |
652 | assert(rrsig); | |
653 | assert(dnskey); | |
547973de | 654 | assert(result); |
2a326321 LP |
655 | assert(rrsig->key->type == DNS_TYPE_RRSIG); |
656 | assert(dnskey->key->type == DNS_TYPE_DNSKEY); | |
2b442ac8 | 657 | |
c629ff58 | 658 | /* Verifies that the RRSet matches the specified "key" in "a", |
2b442ac8 | 659 | * using the signature "rrsig" and the key "dnskey". It's |
c629ff58 | 660 | * assumed that RRSIG and DNSKEY match. */ |
2b442ac8 | 661 | |
97c67192 LP |
662 | r = dnssec_rrsig_prepare(rrsig); |
663 | if (r == -EINVAL) { | |
664 | *result = DNSSEC_INVALID; | |
665 | return r; | |
666 | } | |
667 | if (r < 0) | |
668 | return r; | |
669 | ||
2a326321 LP |
670 | r = dnssec_rrsig_expired(rrsig, realtime); |
671 | if (r < 0) | |
672 | return r; | |
547973de LP |
673 | if (r > 0) { |
674 | *result = DNSSEC_SIGNATURE_EXPIRED; | |
675 | return 0; | |
676 | } | |
2a326321 | 677 | |
1c02e7ba | 678 | name = dns_resource_key_name(key); |
588c53d0 LP |
679 | |
680 | /* Some keys may only appear signed in the zone apex, and are invalid anywhere else. (SOA, NS...) */ | |
681 | if (dns_type_apex_only(rrsig->rrsig.type_covered)) { | |
682 | r = dns_name_equal(rrsig->rrsig.signer, name); | |
683 | if (r < 0) | |
684 | return r; | |
685 | if (r == 0) { | |
686 | *result = DNSSEC_INVALID; | |
687 | return 0; | |
688 | } | |
689 | } | |
690 | ||
691 | /* OTOH DS RRs may not appear in the zone apex, but are valid everywhere else. */ | |
692 | if (rrsig->rrsig.type_covered == DNS_TYPE_DS) { | |
693 | r = dns_name_equal(rrsig->rrsig.signer, name); | |
694 | if (r < 0) | |
695 | return r; | |
696 | if (r > 0) { | |
697 | *result = DNSSEC_INVALID; | |
698 | return 0; | |
699 | } | |
700 | } | |
701 | ||
7715f91d | 702 | /* Determine the "Source of Synthesis" and whether this is a wildcard RRSIG */ |
588c53d0 | 703 | r = dns_name_suffix(name, rrsig->rrsig.labels, &source); |
7715f91d LP |
704 | if (r < 0) |
705 | return r; | |
e8233bce LP |
706 | if (r > 0 && !dns_type_may_wildcard(rrsig->rrsig.type_covered)) { |
707 | /* We refuse to validate NSEC3 or SOA RRs that are synthesized from wildcards */ | |
708 | *result = DNSSEC_INVALID; | |
709 | return 0; | |
710 | } | |
7160eb1b LP |
711 | if (r == 1) { |
712 | /* If we stripped a single label, then let's see if that maybe was "*". If so, we are not really | |
713 | * synthesized from a wildcard, we are the wildcard itself. Treat that like a normal name. */ | |
588c53d0 | 714 | r = dns_name_startswith(name, "*"); |
7160eb1b LP |
715 | if (r < 0) |
716 | return r; | |
717 | if (r > 0) | |
588c53d0 | 718 | source = name; |
7160eb1b LP |
719 | |
720 | wildcard = r == 0; | |
721 | } else | |
722 | wildcard = r > 0; | |
7715f91d | 723 | |
2b442ac8 | 724 | /* Collect all relevant RRs in a single array, so that we can look at the RRset */ |
0f23174c | 725 | list = newa(DnsResourceRecord *, dns_answer_size(a)); |
2b442ac8 LP |
726 | |
727 | DNS_ANSWER_FOREACH(rr, a) { | |
728 | r = dns_resource_key_equal(key, rr->key); | |
729 | if (r < 0) | |
730 | return r; | |
731 | if (r == 0) | |
732 | continue; | |
733 | ||
734 | /* We need the wire format for ordering, and digest calculation */ | |
735 | r = dns_resource_record_to_wire_format(rr, true); | |
736 | if (r < 0) | |
737 | return r; | |
738 | ||
739 | list[n++] = rr; | |
935a999f TG |
740 | |
741 | if (n > VERIFY_RRS_MAX) | |
742 | return -E2BIG; | |
2b442ac8 LP |
743 | } |
744 | ||
745 | if (n <= 0) | |
746 | return -ENODATA; | |
747 | ||
748 | /* Bring the RRs into canonical order */ | |
93bab288 | 749 | typesafe_qsort(list, n, rr_compare); |
2b442ac8 | 750 | |
2fe21124 | 751 | f = open_memstream_unlocked(&sig_data, &sig_size); |
cb9eeb06 MCO |
752 | if (!f) |
753 | return -ENOMEM; | |
2b442ac8 | 754 | |
cb9eeb06 MCO |
755 | fwrite_uint16(f, rrsig->rrsig.type_covered); |
756 | fwrite_uint8(f, rrsig->rrsig.algorithm); | |
757 | fwrite_uint8(f, rrsig->rrsig.labels); | |
758 | fwrite_uint32(f, rrsig->rrsig.original_ttl); | |
759 | fwrite_uint32(f, rrsig->rrsig.expiration); | |
760 | fwrite_uint32(f, rrsig->rrsig.inception); | |
761 | fwrite_uint16(f, rrsig->rrsig.key_tag); | |
2b442ac8 LP |
762 | |
763 | r = dns_name_to_wire_format(rrsig->rrsig.signer, wire_format_name, sizeof(wire_format_name), true); | |
764 | if (r < 0) | |
8530efc1 | 765 | return r; |
cb9eeb06 | 766 | fwrite(wire_format_name, 1, r, f); |
2b442ac8 | 767 | |
7715f91d LP |
768 | /* Convert the source of synthesis into wire format */ |
769 | r = dns_name_to_wire_format(source, wire_format_name, sizeof(wire_format_name), true); | |
770 | if (r < 0) | |
8530efc1 | 771 | return r; |
7715f91d | 772 | |
2b442ac8 LP |
773 | for (k = 0; k < n; k++) { |
774 | size_t l; | |
7715f91d | 775 | |
2b442ac8 LP |
776 | rr = list[k]; |
777 | ||
7715f91d LP |
778 | /* Hash the source of synthesis. If this is a wildcard, then prefix it with the *. label */ |
779 | if (wildcard) | |
cb9eeb06 MCO |
780 | fwrite((uint8_t[]) { 1, '*'}, sizeof(uint8_t), 2, f); |
781 | fwrite(wire_format_name, 1, r, f); | |
2b442ac8 | 782 | |
cb9eeb06 MCO |
783 | fwrite_uint16(f, rr->key->type); |
784 | fwrite_uint16(f, rr->key->class); | |
785 | fwrite_uint32(f, rrsig->rrsig.original_ttl); | |
2b442ac8 | 786 | |
85aeaccc | 787 | l = DNS_RESOURCE_RECORD_RDATA_SIZE(rr); |
2b442ac8 LP |
788 | assert(l <= 0xFFFF); |
789 | ||
cb9eeb06 MCO |
790 | fwrite_uint16(f, (uint16_t) l); |
791 | fwrite(DNS_RESOURCE_RECORD_RDATA(rr), 1, l, f); | |
2b442ac8 LP |
792 | } |
793 | ||
cb9eeb06 MCO |
794 | r = fflush_and_check(f); |
795 | if (r < 0) | |
796 | return r; | |
797 | ||
798 | initialize_libgcrypt(false); | |
799 | ||
800 | switch (rrsig->rrsig.algorithm) { | |
801 | #if GCRYPT_VERSION_NUMBER >= 0x010600 | |
802 | case DNSSEC_ALGORITHM_ED25519: | |
803 | break; | |
804 | #else | |
805 | case DNSSEC_ALGORITHM_ED25519: | |
806 | #endif | |
807 | case DNSSEC_ALGORITHM_ED448: | |
808 | *result = DNSSEC_UNSUPPORTED_ALGORITHM; | |
8530efc1 | 809 | return 0; |
cb9eeb06 MCO |
810 | default: |
811 | /* OK, the RRs are now in canonical order. Let's calculate the digest */ | |
812 | md_algorithm = algorithm_to_gcrypt_md(rrsig->rrsig.algorithm); | |
813 | if (md_algorithm == -EOPNOTSUPP) { | |
814 | *result = DNSSEC_UNSUPPORTED_ALGORITHM; | |
8530efc1 | 815 | return 0; |
cb9eeb06 | 816 | } |
8530efc1 ZJS |
817 | if (md_algorithm < 0) |
818 | return md_algorithm; | |
cb9eeb06 MCO |
819 | |
820 | gcry_md_open(&md, md_algorithm, 0); | |
8530efc1 ZJS |
821 | if (!md) |
822 | return -EIO; | |
cb9eeb06 MCO |
823 | |
824 | hash_size = gcry_md_get_algo_dlen(md_algorithm); | |
825 | assert(hash_size > 0); | |
826 | ||
827 | gcry_md_write(md, sig_data, sig_size); | |
828 | ||
829 | hash = gcry_md_read(md, 0); | |
8530efc1 ZJS |
830 | if (!hash) |
831 | return -EIO; | |
2b442ac8 LP |
832 | } |
833 | ||
e0240c64 LP |
834 | switch (rrsig->rrsig.algorithm) { |
835 | ||
836 | case DNSSEC_ALGORITHM_RSASHA1: | |
837 | case DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1: | |
838 | case DNSSEC_ALGORITHM_RSASHA256: | |
839 | case DNSSEC_ALGORITHM_RSASHA512: | |
840 | r = dnssec_rsa_verify( | |
ca994e85 | 841 | gcry_md_algo_name(md_algorithm), |
e0240c64 LP |
842 | hash, hash_size, |
843 | rrsig, | |
844 | dnskey); | |
845 | break; | |
846 | ||
847 | case DNSSEC_ALGORITHM_ECDSAP256SHA256: | |
848 | case DNSSEC_ALGORITHM_ECDSAP384SHA384: | |
849 | r = dnssec_ecdsa_verify( | |
ca994e85 | 850 | gcry_md_algo_name(md_algorithm), |
e0240c64 LP |
851 | rrsig->rrsig.algorithm, |
852 | hash, hash_size, | |
853 | rrsig, | |
854 | dnskey); | |
855 | break; | |
cb9eeb06 MCO |
856 | #if GCRYPT_VERSION_NUMBER >= 0x010600 |
857 | case DNSSEC_ALGORITHM_ED25519: | |
858 | r = dnssec_eddsa_verify( | |
859 | rrsig->rrsig.algorithm, | |
860 | sig_data, sig_size, | |
861 | rrsig, | |
862 | dnskey); | |
863 | break; | |
864 | #endif | |
e0240c64 | 865 | } |
2b442ac8 | 866 | if (r < 0) |
8530efc1 | 867 | return r; |
2b442ac8 | 868 | |
97c67192 LP |
869 | /* Now, fix the ttl, expiry, and remember the synthesizing source and the signer */ |
870 | if (r > 0) | |
871 | dnssec_fix_rrset_ttl(list, n, rrsig, realtime); | |
872 | ||
873 | if (r == 0) | |
0c7bff0a LP |
874 | *result = DNSSEC_INVALID; |
875 | else if (wildcard) | |
876 | *result = DNSSEC_VALIDATED_WILDCARD; | |
877 | else | |
878 | *result = DNSSEC_VALIDATED; | |
97c67192 | 879 | |
8530efc1 | 880 | return 0; |
2b442ac8 LP |
881 | } |
882 | ||
0c857028 | 883 | int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, bool revoked_ok) { |
2b442ac8 LP |
884 | |
885 | assert(rrsig); | |
886 | assert(dnskey); | |
887 | ||
888 | /* Checks if the specified DNSKEY RR matches the key used for | |
889 | * the signature in the specified RRSIG RR */ | |
890 | ||
891 | if (rrsig->key->type != DNS_TYPE_RRSIG) | |
892 | return -EINVAL; | |
893 | ||
894 | if (dnskey->key->type != DNS_TYPE_DNSKEY) | |
895 | return 0; | |
896 | if (dnskey->key->class != rrsig->key->class) | |
897 | return 0; | |
898 | if ((dnskey->dnskey.flags & DNSKEY_FLAG_ZONE_KEY) == 0) | |
899 | return 0; | |
0c857028 | 900 | if (!revoked_ok && (dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE)) |
28b8191e | 901 | return 0; |
2b442ac8 LP |
902 | if (dnskey->dnskey.protocol != 3) |
903 | return 0; | |
904 | if (dnskey->dnskey.algorithm != rrsig->rrsig.algorithm) | |
905 | return 0; | |
906 | ||
0c857028 | 907 | if (dnssec_keytag(dnskey, false) != rrsig->rrsig.key_tag) |
2b442ac8 LP |
908 | return 0; |
909 | ||
1c02e7ba | 910 | return dns_name_equal(dns_resource_key_name(dnskey->key), rrsig->rrsig.signer); |
2b442ac8 LP |
911 | } |
912 | ||
105e1512 | 913 | int dnssec_key_match_rrsig(const DnsResourceKey *key, DnsResourceRecord *rrsig) { |
2b442ac8 LP |
914 | assert(key); |
915 | assert(rrsig); | |
916 | ||
917 | /* Checks if the specified RRSIG RR protects the RRSet of the specified RR key. */ | |
918 | ||
919 | if (rrsig->key->type != DNS_TYPE_RRSIG) | |
920 | return 0; | |
921 | if (rrsig->key->class != key->class) | |
922 | return 0; | |
923 | if (rrsig->rrsig.type_covered != key->type) | |
924 | return 0; | |
925 | ||
1c02e7ba | 926 | return dns_name_equal(dns_resource_key_name(rrsig->key), dns_resource_key_name(key)); |
2b442ac8 LP |
927 | } |
928 | ||
2a326321 LP |
929 | int dnssec_verify_rrset_search( |
930 | DnsAnswer *a, | |
0c857028 | 931 | const DnsResourceKey *key, |
2a326321 | 932 | DnsAnswer *validated_dnskeys, |
547973de | 933 | usec_t realtime, |
0c7bff0a LP |
934 | DnssecResult *result, |
935 | DnsResourceRecord **ret_rrsig) { | |
2a326321 | 936 | |
203f1b35 | 937 | bool found_rrsig = false, found_invalid = false, found_expired_rrsig = false, found_unsupported_algorithm = false; |
2b442ac8 LP |
938 | DnsResourceRecord *rrsig; |
939 | int r; | |
940 | ||
941 | assert(key); | |
547973de | 942 | assert(result); |
2b442ac8 | 943 | |
105e1512 | 944 | /* Verifies all RRs from "a" that match the key "key" against DNSKEYs in "validated_dnskeys" */ |
2b442ac8 LP |
945 | |
946 | if (!a || a->n_rrs <= 0) | |
947 | return -ENODATA; | |
948 | ||
949 | /* Iterate through each RRSIG RR. */ | |
950 | DNS_ANSWER_FOREACH(rrsig, a) { | |
951 | DnsResourceRecord *dnskey; | |
105e1512 | 952 | DnsAnswerFlags flags; |
2b442ac8 | 953 | |
203f1b35 | 954 | /* Is this an RRSIG RR that applies to RRs matching our key? */ |
2b442ac8 LP |
955 | r = dnssec_key_match_rrsig(key, rrsig); |
956 | if (r < 0) | |
957 | return r; | |
958 | if (r == 0) | |
959 | continue; | |
960 | ||
961 | found_rrsig = true; | |
962 | ||
547973de | 963 | /* Look for a matching key */ |
105e1512 | 964 | DNS_ANSWER_FOREACH_FLAGS(dnskey, flags, validated_dnskeys) { |
547973de | 965 | DnssecResult one_result; |
2b442ac8 | 966 | |
105e1512 LP |
967 | if ((flags & DNS_ANSWER_AUTHENTICATED) == 0) |
968 | continue; | |
969 | ||
203f1b35 | 970 | /* Is this a DNSKEY RR that matches they key of our RRSIG? */ |
0c857028 | 971 | r = dnssec_rrsig_match_dnskey(rrsig, dnskey, false); |
2b442ac8 LP |
972 | if (r < 0) |
973 | return r; | |
974 | if (r == 0) | |
975 | continue; | |
976 | ||
2a326321 LP |
977 | /* Take the time here, if it isn't set yet, so |
978 | * that we do all validations with the same | |
979 | * time. */ | |
980 | if (realtime == USEC_INFINITY) | |
981 | realtime = now(CLOCK_REALTIME); | |
982 | ||
2b442ac8 LP |
983 | /* Yay, we found a matching RRSIG with a matching |
984 | * DNSKEY, awesome. Now let's verify all entries of | |
985 | * the RRSet against the RRSIG and DNSKEY | |
986 | * combination. */ | |
987 | ||
547973de | 988 | r = dnssec_verify_rrset(a, key, rrsig, dnskey, realtime, &one_result); |
203f1b35 | 989 | if (r < 0) |
2b442ac8 | 990 | return r; |
203f1b35 LP |
991 | |
992 | switch (one_result) { | |
993 | ||
994 | case DNSSEC_VALIDATED: | |
0c7bff0a | 995 | case DNSSEC_VALIDATED_WILDCARD: |
203f1b35 | 996 | /* Yay, the RR has been validated, |
ee3d6aff | 997 | * return immediately, but fix up the expiry */ |
0c7bff0a LP |
998 | if (ret_rrsig) |
999 | *ret_rrsig = rrsig; | |
1000 | ||
1001 | *result = one_result; | |
547973de | 1002 | return 0; |
2b442ac8 | 1003 | |
203f1b35 LP |
1004 | case DNSSEC_INVALID: |
1005 | /* If the signature is invalid, let's try another | |
1006 | key and/or signature. After all they | |
1007 | key_tags and stuff are not unique, and | |
1008 | might be shared by multiple keys. */ | |
1009 | found_invalid = true; | |
1010 | continue; | |
1011 | ||
1012 | case DNSSEC_UNSUPPORTED_ALGORITHM: | |
1013 | /* If the key algorithm is | |
1014 | unsupported, try another | |
1015 | RRSIG/DNSKEY pair, but remember we | |
1016 | encountered this, so that we can | |
1017 | return a proper error when we | |
1018 | encounter nothing better. */ | |
1019 | found_unsupported_algorithm = true; | |
1020 | continue; | |
1021 | ||
1022 | case DNSSEC_SIGNATURE_EXPIRED: | |
1023 | /* If the signature is expired, try | |
1024 | another one, but remember it, so | |
1025 | that we can return this */ | |
1026 | found_expired_rrsig = true; | |
1027 | continue; | |
1028 | ||
1029 | default: | |
1030 | assert_not_reached("Unexpected DNSSEC validation result"); | |
1031 | } | |
2b442ac8 LP |
1032 | } |
1033 | } | |
1034 | ||
203f1b35 LP |
1035 | if (found_expired_rrsig) |
1036 | *result = DNSSEC_SIGNATURE_EXPIRED; | |
1037 | else if (found_unsupported_algorithm) | |
1038 | *result = DNSSEC_UNSUPPORTED_ALGORITHM; | |
1039 | else if (found_invalid) | |
547973de LP |
1040 | *result = DNSSEC_INVALID; |
1041 | else if (found_rrsig) | |
1042 | *result = DNSSEC_MISSING_KEY; | |
1043 | else | |
1044 | *result = DNSSEC_NO_SIGNATURE; | |
2b442ac8 | 1045 | |
0c7bff0a LP |
1046 | if (ret_rrsig) |
1047 | *ret_rrsig = NULL; | |
1048 | ||
547973de | 1049 | return 0; |
2b442ac8 LP |
1050 | } |
1051 | ||
105e1512 LP |
1052 | int dnssec_has_rrsig(DnsAnswer *a, const DnsResourceKey *key) { |
1053 | DnsResourceRecord *rr; | |
1054 | int r; | |
1055 | ||
5238e957 | 1056 | /* Checks whether there's at least one RRSIG in 'a' that protects RRs of the specified key */ |
105e1512 LP |
1057 | |
1058 | DNS_ANSWER_FOREACH(rr, a) { | |
1059 | r = dnssec_key_match_rrsig(key, rr); | |
1060 | if (r < 0) | |
1061 | return r; | |
1062 | if (r > 0) | |
1063 | return 1; | |
1064 | } | |
1065 | ||
1066 | return 0; | |
1067 | } | |
1068 | ||
ca994e85 | 1069 | static int digest_to_gcrypt_md(uint8_t algorithm) { |
a1972a91 | 1070 | |
fbf1a66d | 1071 | /* Translates a DNSSEC digest algorithm into a gcrypt digest identifier */ |
a1972a91 LP |
1072 | |
1073 | switch (algorithm) { | |
1074 | ||
1075 | case DNSSEC_DIGEST_SHA1: | |
1076 | return GCRY_MD_SHA1; | |
1077 | ||
1078 | case DNSSEC_DIGEST_SHA256: | |
1079 | return GCRY_MD_SHA256; | |
1080 | ||
af22c65b LP |
1081 | case DNSSEC_DIGEST_SHA384: |
1082 | return GCRY_MD_SHA384; | |
1083 | ||
a1972a91 LP |
1084 | default: |
1085 | return -EOPNOTSUPP; | |
1086 | } | |
1087 | } | |
1088 | ||
96bb7673 | 1089 | int dnssec_verify_dnskey_by_ds(DnsResourceRecord *dnskey, DnsResourceRecord *ds, bool mask_revoke) { |
5e55cde9 | 1090 | uint8_t wire_format[DNS_WIRE_FORMAT_HOSTNAME_MAX]; |
15c53310 | 1091 | _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL; |
a1972a91 | 1092 | size_t hash_size; |
ca994e85 | 1093 | int md_algorithm, r; |
2b442ac8 | 1094 | void *result; |
2b442ac8 LP |
1095 | |
1096 | assert(dnskey); | |
1097 | assert(ds); | |
1098 | ||
1099 | /* Implements DNSKEY verification by a DS, according to RFC 4035, section 5.2 */ | |
1100 | ||
1101 | if (dnskey->key->type != DNS_TYPE_DNSKEY) | |
1102 | return -EINVAL; | |
1103 | if (ds->key->type != DNS_TYPE_DS) | |
1104 | return -EINVAL; | |
1105 | if ((dnskey->dnskey.flags & DNSKEY_FLAG_ZONE_KEY) == 0) | |
1106 | return -EKEYREJECTED; | |
0c857028 LP |
1107 | if (!mask_revoke && (dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE)) |
1108 | return -EKEYREJECTED; | |
2b442ac8 LP |
1109 | if (dnskey->dnskey.protocol != 3) |
1110 | return -EKEYREJECTED; | |
1111 | ||
2b442ac8 LP |
1112 | if (dnskey->dnskey.algorithm != ds->ds.algorithm) |
1113 | return 0; | |
0c857028 | 1114 | if (dnssec_keytag(dnskey, mask_revoke) != ds->ds.key_tag) |
2b442ac8 LP |
1115 | return 0; |
1116 | ||
91e023d8 | 1117 | initialize_libgcrypt(false); |
0638401a | 1118 | |
ca994e85 LP |
1119 | md_algorithm = digest_to_gcrypt_md(ds->ds.digest_type); |
1120 | if (md_algorithm < 0) | |
1121 | return md_algorithm; | |
2b442ac8 | 1122 | |
ca994e85 | 1123 | hash_size = gcry_md_get_algo_dlen(md_algorithm); |
a1972a91 | 1124 | assert(hash_size > 0); |
2b442ac8 | 1125 | |
a1972a91 LP |
1126 | if (ds->ds.digest_size != hash_size) |
1127 | return 0; | |
2b442ac8 | 1128 | |
c910c520 | 1129 | r = dns_name_to_wire_format(dns_resource_key_name(dnskey->key), wire_format, sizeof(wire_format), true); |
a1972a91 LP |
1130 | if (r < 0) |
1131 | return r; | |
2b442ac8 | 1132 | |
ca994e85 | 1133 | gcry_md_open(&md, md_algorithm, 0); |
2b442ac8 LP |
1134 | if (!md) |
1135 | return -EIO; | |
1136 | ||
c910c520 | 1137 | gcry_md_write(md, wire_format, r); |
0c857028 LP |
1138 | if (mask_revoke) |
1139 | md_add_uint16(md, dnskey->dnskey.flags & ~DNSKEY_FLAG_REVOKE); | |
1140 | else | |
1141 | md_add_uint16(md, dnskey->dnskey.flags); | |
2b442ac8 LP |
1142 | md_add_uint8(md, dnskey->dnskey.protocol); |
1143 | md_add_uint8(md, dnskey->dnskey.algorithm); | |
1144 | gcry_md_write(md, dnskey->dnskey.key, dnskey->dnskey.key_size); | |
1145 | ||
1146 | result = gcry_md_read(md, 0); | |
15c53310 ZJS |
1147 | if (!result) |
1148 | return -EIO; | |
2b442ac8 | 1149 | |
c910c520 | 1150 | return memcmp(result, ds->ds.digest, ds->ds.digest_size) == 0; |
2b442ac8 | 1151 | } |
24710c48 | 1152 | |
96bb7673 | 1153 | int dnssec_verify_dnskey_by_ds_search(DnsResourceRecord *dnskey, DnsAnswer *validated_ds) { |
547973de | 1154 | DnsResourceRecord *ds; |
105e1512 | 1155 | DnsAnswerFlags flags; |
547973de LP |
1156 | int r; |
1157 | ||
1158 | assert(dnskey); | |
1159 | ||
1160 | if (dnskey->key->type != DNS_TYPE_DNSKEY) | |
1161 | return 0; | |
1162 | ||
105e1512 LP |
1163 | DNS_ANSWER_FOREACH_FLAGS(ds, flags, validated_ds) { |
1164 | ||
1165 | if ((flags & DNS_ANSWER_AUTHENTICATED) == 0) | |
1166 | continue; | |
547973de LP |
1167 | |
1168 | if (ds->key->type != DNS_TYPE_DS) | |
1169 | continue; | |
d1c4ee32 LP |
1170 | if (ds->key->class != dnskey->key->class) |
1171 | continue; | |
1172 | ||
1c02e7ba | 1173 | r = dns_name_equal(dns_resource_key_name(dnskey->key), dns_resource_key_name(ds->key)); |
d1c4ee32 LP |
1174 | if (r < 0) |
1175 | return r; | |
1176 | if (r == 0) | |
1177 | continue; | |
1178 | ||
96bb7673 | 1179 | r = dnssec_verify_dnskey_by_ds(dnskey, ds, false); |
54b778e7 LP |
1180 | if (IN_SET(r, -EKEYREJECTED, -EOPNOTSUPP)) |
1181 | return 0; /* The DNSKEY is revoked or otherwise invalid, or we don't support the digest algorithm */ | |
547973de LP |
1182 | if (r < 0) |
1183 | return r; | |
1184 | if (r > 0) | |
1185 | return 1; | |
1186 | } | |
1187 | ||
1188 | return 0; | |
1189 | } | |
1190 | ||
d15ad742 LP |
1191 | static int nsec3_hash_to_gcrypt_md(uint8_t algorithm) { |
1192 | ||
1193 | /* Translates a DNSSEC NSEC3 hash algorithm into a gcrypt digest identifier */ | |
1194 | ||
1195 | switch (algorithm) { | |
1196 | ||
1197 | case NSEC3_ALGORITHM_SHA1: | |
1198 | return GCRY_MD_SHA1; | |
1199 | ||
1200 | default: | |
1201 | return -EOPNOTSUPP; | |
1202 | } | |
1203 | } | |
1204 | ||
1d3db294 | 1205 | int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) { |
5e55cde9 | 1206 | uint8_t wire_format[DNS_WIRE_FORMAT_HOSTNAME_MAX]; |
72667f08 LP |
1207 | gcry_md_hd_t md = NULL; |
1208 | size_t hash_size; | |
1209 | int algorithm; | |
1210 | void *result; | |
1211 | unsigned k; | |
1212 | int r; | |
1213 | ||
1214 | assert(nsec3); | |
1215 | assert(name); | |
1216 | assert(ret); | |
1217 | ||
1218 | if (nsec3->key->type != DNS_TYPE_NSEC3) | |
1219 | return -EINVAL; | |
1220 | ||
baaa35ad ZJS |
1221 | if (nsec3->nsec3.iterations > NSEC3_ITERATIONS_MAX) |
1222 | return log_debug_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), | |
1223 | "Ignoring NSEC3 RR %s with excessive number of iterations.", | |
1224 | dns_resource_record_to_string(nsec3)); | |
a8f158b9 | 1225 | |
d15ad742 | 1226 | algorithm = nsec3_hash_to_gcrypt_md(nsec3->nsec3.algorithm); |
72667f08 LP |
1227 | if (algorithm < 0) |
1228 | return algorithm; | |
1229 | ||
91e023d8 | 1230 | initialize_libgcrypt(false); |
72667f08 LP |
1231 | |
1232 | hash_size = gcry_md_get_algo_dlen(algorithm); | |
1233 | assert(hash_size > 0); | |
1234 | ||
1235 | if (nsec3->nsec3.next_hashed_name_size != hash_size) | |
1236 | return -EINVAL; | |
1237 | ||
1238 | r = dns_name_to_wire_format(name, wire_format, sizeof(wire_format), true); | |
1239 | if (r < 0) | |
1240 | return r; | |
1241 | ||
1242 | gcry_md_open(&md, algorithm, 0); | |
1243 | if (!md) | |
1244 | return -EIO; | |
1245 | ||
1246 | gcry_md_write(md, wire_format, r); | |
1247 | gcry_md_write(md, nsec3->nsec3.salt, nsec3->nsec3.salt_size); | |
1248 | ||
1249 | result = gcry_md_read(md, 0); | |
1250 | if (!result) { | |
1251 | r = -EIO; | |
1252 | goto finish; | |
1253 | } | |
1254 | ||
1255 | for (k = 0; k < nsec3->nsec3.iterations; k++) { | |
1256 | uint8_t tmp[hash_size]; | |
1257 | memcpy(tmp, result, hash_size); | |
1258 | ||
1259 | gcry_md_reset(md); | |
1260 | gcry_md_write(md, tmp, hash_size); | |
1261 | gcry_md_write(md, nsec3->nsec3.salt, nsec3->nsec3.salt_size); | |
1262 | ||
1263 | result = gcry_md_read(md, 0); | |
1264 | if (!result) { | |
1265 | r = -EIO; | |
1266 | goto finish; | |
1267 | } | |
1268 | } | |
1269 | ||
1270 | memcpy(ret, result, hash_size); | |
1271 | r = (int) hash_size; | |
1272 | ||
1273 | finish: | |
1274 | gcry_md_close(md); | |
1275 | return r; | |
1276 | } | |
1277 | ||
3f5ecaad | 1278 | static int nsec3_is_good(DnsResourceRecord *rr, DnsResourceRecord *nsec3) { |
db5b0e92 LP |
1279 | const char *a, *b; |
1280 | int r; | |
1281 | ||
1282 | assert(rr); | |
1283 | ||
db5b0e92 LP |
1284 | if (rr->key->type != DNS_TYPE_NSEC3) |
1285 | return 0; | |
1286 | ||
1f133e0d | 1287 | /* RFC 5155, Section 8.2 says we MUST ignore NSEC3 RRs with flags != 0 or 1 */ |
db5b0e92 LP |
1288 | if (!IN_SET(rr->nsec3.flags, 0, 1)) |
1289 | return 0; | |
1290 | ||
d15ad742 LP |
1291 | /* Ignore NSEC3 RRs whose algorithm we don't know */ |
1292 | if (nsec3_hash_to_gcrypt_md(rr->nsec3.algorithm) < 0) | |
1293 | return 0; | |
a8f158b9 LP |
1294 | /* Ignore NSEC3 RRs with an excessive number of required iterations */ |
1295 | if (rr->nsec3.iterations > NSEC3_ITERATIONS_MAX) | |
1296 | return 0; | |
d15ad742 | 1297 | |
cbd100ac LP |
1298 | /* Ignore NSEC3 RRs generated from wildcards. If these NSEC3 RRs weren't correctly signed we can't make this |
1299 | * check (since rr->n_skip_labels_source is -1), but that's OK, as we won't trust them anyway in that case. */ | |
f5fbe71d | 1300 | if (!IN_SET(rr->n_skip_labels_source, 0, UINT_MAX)) |
93a3b929 LP |
1301 | return 0; |
1302 | /* Ignore NSEC3 RRs that are located anywhere else than one label below the zone */ | |
f5fbe71d | 1303 | if (!IN_SET(rr->n_skip_labels_signer, 1, UINT_MAX)) |
93a3b929 LP |
1304 | return 0; |
1305 | ||
db5b0e92 LP |
1306 | if (!nsec3) |
1307 | return 1; | |
1308 | ||
1309 | /* If a second NSEC3 RR is specified, also check if they are from the same zone. */ | |
1310 | ||
1311 | if (nsec3 == rr) /* Shortcut */ | |
1312 | return 1; | |
1313 | ||
1314 | if (rr->key->class != nsec3->key->class) | |
1315 | return 0; | |
1316 | if (rr->nsec3.algorithm != nsec3->nsec3.algorithm) | |
1317 | return 0; | |
1318 | if (rr->nsec3.iterations != nsec3->nsec3.iterations) | |
1319 | return 0; | |
1320 | if (rr->nsec3.salt_size != nsec3->nsec3.salt_size) | |
1321 | return 0; | |
1f66559c | 1322 | if (memcmp_safe(rr->nsec3.salt, nsec3->nsec3.salt, rr->nsec3.salt_size) != 0) |
db5b0e92 LP |
1323 | return 0; |
1324 | ||
1c02e7ba | 1325 | a = dns_resource_key_name(rr->key); |
db5b0e92 | 1326 | r = dns_name_parent(&a); /* strip off hash */ |
f20db199 | 1327 | if (r <= 0) |
db5b0e92 | 1328 | return r; |
db5b0e92 | 1329 | |
1c02e7ba | 1330 | b = dns_resource_key_name(nsec3->key); |
db5b0e92 | 1331 | r = dns_name_parent(&b); /* strip off hash */ |
f20db199 | 1332 | if (r <= 0) |
db5b0e92 | 1333 | return r; |
db5b0e92 | 1334 | |
93a3b929 | 1335 | /* Make sure both have the same parent */ |
db5b0e92 LP |
1336 | return dns_name_equal(a, b); |
1337 | } | |
1338 | ||
cdbffec0 LP |
1339 | static int nsec3_hashed_domain_format(const uint8_t *hashed, size_t hashed_size, const char *zone, char **ret) { |
1340 | _cleanup_free_ char *l = NULL; | |
1341 | char *j; | |
1342 | ||
1343 | assert(hashed); | |
1344 | assert(hashed_size > 0); | |
1345 | assert(zone); | |
1346 | assert(ret); | |
1347 | ||
1348 | l = base32hexmem(hashed, hashed_size, false); | |
1349 | if (!l) | |
1350 | return -ENOMEM; | |
1351 | ||
605405c6 | 1352 | j = strjoin(l, ".", zone); |
cdbffec0 LP |
1353 | if (!j) |
1354 | return -ENOMEM; | |
1355 | ||
1356 | *ret = j; | |
1357 | return (int) hashed_size; | |
1358 | } | |
1359 | ||
1360 | static int nsec3_hashed_domain_make(DnsResourceRecord *nsec3, const char *domain, const char *zone, char **ret) { | |
105e1512 | 1361 | uint8_t hashed[DNSSEC_HASH_SIZE_MAX]; |
6f76ec5a TG |
1362 | int hashed_size; |
1363 | ||
1364 | assert(nsec3); | |
1365 | assert(domain); | |
1366 | assert(zone); | |
1367 | assert(ret); | |
1368 | ||
1369 | hashed_size = dnssec_nsec3_hash(nsec3, domain, hashed); | |
1370 | if (hashed_size < 0) | |
1371 | return hashed_size; | |
1372 | ||
cdbffec0 | 1373 | return nsec3_hashed_domain_format(hashed, (size_t) hashed_size, zone, ret); |
6f76ec5a TG |
1374 | } |
1375 | ||
35ad41d3 TG |
1376 | /* See RFC 5155, Section 8 |
1377 | * First try to find a NSEC3 record that matches our query precisely, if that fails, find the closest | |
1378 | * enclosure. Secondly, find a proof that there is no closer enclosure and either a proof that there | |
1379 | * is no wildcard domain as a direct descendant of the closest enclosure, or find an NSEC3 record that | |
1380 | * matches the wildcard domain. | |
1381 | * | |
1382 | * Based on this we can prove either the existence of the record in @key, or NXDOMAIN or NODATA, or | |
d51c4fca | 1383 | * that there is no proof either way. The latter is the case if a proof of non-existence of a given |
35ad41d3 TG |
1384 | * name uses an NSEC3 record with the opt-out bit set. Lastly, if we are given insufficient NSEC3 records |
1385 | * to conclude anything we indicate this by returning NO_RR. */ | |
d3760be0 | 1386 | static int dnssec_test_nsec3(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) { |
d41084a5 LP |
1387 | _cleanup_free_ char *next_closer_domain = NULL, *wildcard_domain = NULL; |
1388 | const char *zone, *p, *pp = NULL, *wildcard; | |
7e35195f | 1389 | DnsResourceRecord *rr, *enclosure_rr, *zone_rr, *wildcard_rr = NULL; |
105e1512 LP |
1390 | DnsAnswerFlags flags; |
1391 | int hashed_size, r; | |
35ad41d3 | 1392 | bool a, no_closer = false, no_wildcard = false, optout = false; |
72667f08 LP |
1393 | |
1394 | assert(key); | |
1395 | assert(result); | |
1396 | ||
d1511b33 TG |
1397 | /* First step, find the zone name and the NSEC3 parameters of the zone. |
1398 | * it is sufficient to look for the longest common suffix we find with | |
1399 | * any NSEC3 RR in the response. Any NSEC3 record will do as all NSEC3 | |
1400 | * records from a given zone in a response must use the same | |
1401 | * parameters. */ | |
1c02e7ba | 1402 | zone = dns_resource_key_name(key); |
13b78323 | 1403 | for (;;) { |
7e35195f | 1404 | DNS_ANSWER_FOREACH_FLAGS(zone_rr, flags, answer) { |
3f5ecaad | 1405 | r = nsec3_is_good(zone_rr, NULL); |
db5b0e92 LP |
1406 | if (r < 0) |
1407 | return r; | |
1408 | if (r == 0) | |
13b78323 LP |
1409 | continue; |
1410 | ||
1c02e7ba | 1411 | r = dns_name_equal_skip(dns_resource_key_name(zone_rr->key), 1, zone); |
13b78323 LP |
1412 | if (r < 0) |
1413 | return r; | |
1414 | if (r > 0) | |
d1511b33 | 1415 | goto found_zone; |
13b78323 LP |
1416 | } |
1417 | ||
1418 | /* Strip one label from the front */ | |
d1511b33 | 1419 | r = dns_name_parent(&zone); |
13b78323 LP |
1420 | if (r < 0) |
1421 | return r; | |
1422 | if (r == 0) | |
1423 | break; | |
1424 | } | |
1425 | ||
1426 | *result = DNSSEC_NSEC_NO_RR; | |
1427 | return 0; | |
1428 | ||
d1511b33 | 1429 | found_zone: |
13b78323 | 1430 | /* Second step, find the closest encloser NSEC3 RR in 'answer' that matches 'key' */ |
1c02e7ba | 1431 | p = dns_resource_key_name(key); |
105e1512 | 1432 | for (;;) { |
6f76ec5a | 1433 | _cleanup_free_ char *hashed_domain = NULL; |
72667f08 | 1434 | |
cdbffec0 | 1435 | hashed_size = nsec3_hashed_domain_make(zone_rr, p, zone, &hashed_domain); |
db5b0e92 LP |
1436 | if (hashed_size == -EOPNOTSUPP) { |
1437 | *result = DNSSEC_NSEC_UNSUPPORTED_ALGORITHM; | |
1438 | return 0; | |
1439 | } | |
1440 | if (hashed_size < 0) | |
1441 | return hashed_size; | |
72667f08 | 1442 | |
d1511b33 | 1443 | DNS_ANSWER_FOREACH_FLAGS(enclosure_rr, flags, answer) { |
db5b0e92 | 1444 | |
3f5ecaad | 1445 | r = nsec3_is_good(enclosure_rr, zone_rr); |
72667f08 LP |
1446 | if (r < 0) |
1447 | return r; | |
105e1512 LP |
1448 | if (r == 0) |
1449 | continue; | |
1450 | ||
d1511b33 | 1451 | if (enclosure_rr->nsec3.next_hashed_name_size != (size_t) hashed_size) |
db5b0e92 | 1452 | continue; |
105e1512 | 1453 | |
1c02e7ba | 1454 | r = dns_name_equal(dns_resource_key_name(enclosure_rr->key), hashed_domain); |
72667f08 LP |
1455 | if (r < 0) |
1456 | return r; | |
ed29bfdc LP |
1457 | if (r > 0) { |
1458 | a = flags & DNS_ANSWER_AUTHENTICATED; | |
13b78323 | 1459 | goto found_closest_encloser; |
ed29bfdc | 1460 | } |
105e1512 LP |
1461 | } |
1462 | ||
1463 | /* We didn't find the closest encloser with this name, | |
1464 | * but let's remember this domain name, it might be | |
1465 | * the next closer name */ | |
1466 | ||
1467 | pp = p; | |
1468 | ||
1469 | /* Strip one label from the front */ | |
1470 | r = dns_name_parent(&p); | |
1471 | if (r < 0) | |
1472 | return r; | |
1473 | if (r == 0) | |
72667f08 | 1474 | break; |
105e1512 | 1475 | } |
72667f08 | 1476 | |
105e1512 LP |
1477 | *result = DNSSEC_NSEC_NO_RR; |
1478 | return 0; | |
72667f08 | 1479 | |
13b78323 | 1480 | found_closest_encloser: |
105e1512 | 1481 | /* We found a closest encloser in 'p'; next closer is 'pp' */ |
72667f08 | 1482 | |
105e1512 | 1483 | if (!pp) { |
352af308 LP |
1484 | /* We have an exact match! If we area looking for a DS RR, then we must insist that we got the NSEC3 RR |
1485 | * from the parent. Otherwise the one from the child. Do so, by checking whether SOA and NS are | |
1486 | * appropriately set. */ | |
1487 | ||
1488 | if (key->type == DNS_TYPE_DS) { | |
1489 | if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_SOA)) | |
1490 | return -EBADMSG; | |
1491 | } else { | |
1492 | if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_NS) && | |
1493 | !bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_SOA)) | |
1494 | return -EBADMSG; | |
1495 | } | |
1496 | ||
105e1512 | 1497 | /* No next closer NSEC3 RR. That means there's a direct NSEC3 RR for our key. */ |
146035b3 TG |
1498 | if (bitmap_isset(enclosure_rr->nsec3.types, key->type)) |
1499 | *result = DNSSEC_NSEC_FOUND; | |
1500 | else if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_CNAME)) | |
1501 | *result = DNSSEC_NSEC_CNAME; | |
1502 | else | |
1503 | *result = DNSSEC_NSEC_NODATA; | |
1504 | ||
d3760be0 LP |
1505 | if (authenticated) |
1506 | *authenticated = a; | |
1507 | if (ttl) | |
1508 | *ttl = enclosure_rr->ttl; | |
146035b3 | 1509 | |
105e1512 LP |
1510 | return 0; |
1511 | } | |
72667f08 | 1512 | |
352af308 LP |
1513 | /* Ensure this is not a DNAME domain, see RFC5155, section 8.3. */ |
1514 | if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_DNAME)) | |
1515 | return -EBADMSG; | |
1516 | ||
1517 | /* Ensure that this data is from the delegated domain | |
1518 | * (i.e. originates from the "lower" DNS server), and isn't | |
1519 | * just glue records (i.e. doesn't originate from the "upper" | |
1520 | * DNS server). */ | |
1521 | if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_NS) && | |
1522 | !bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_SOA)) | |
1523 | return -EBADMSG; | |
1524 | ||
35ad41d3 TG |
1525 | /* Prove that there is no next closer and whether or not there is a wildcard domain. */ |
1526 | ||
d41084a5 | 1527 | wildcard = strjoina("*.", p); |
cdbffec0 | 1528 | r = nsec3_hashed_domain_make(enclosure_rr, wildcard, zone, &wildcard_domain); |
105e1512 LP |
1529 | if (r < 0) |
1530 | return r; | |
1531 | if (r != hashed_size) | |
1532 | return -EBADMSG; | |
72667f08 | 1533 | |
cdbffec0 | 1534 | r = nsec3_hashed_domain_make(enclosure_rr, pp, zone, &next_closer_domain); |
105e1512 LP |
1535 | if (r < 0) |
1536 | return r; | |
1537 | if (r != hashed_size) | |
1538 | return -EBADMSG; | |
72667f08 | 1539 | |
105e1512 | 1540 | DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) { |
cdbffec0 | 1541 | _cleanup_free_ char *next_hashed_domain = NULL; |
105e1512 | 1542 | |
3f5ecaad | 1543 | r = nsec3_is_good(rr, zone_rr); |
105e1512 LP |
1544 | if (r < 0) |
1545 | return r; | |
1546 | if (r == 0) | |
1547 | continue; | |
1548 | ||
cdbffec0 LP |
1549 | r = nsec3_hashed_domain_format(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size, zone, &next_hashed_domain); |
1550 | if (r < 0) | |
1551 | return r; | |
105e1512 | 1552 | |
1c02e7ba | 1553 | r = dns_name_between(dns_resource_key_name(rr->key), next_closer_domain, next_hashed_domain); |
105e1512 LP |
1554 | if (r < 0) |
1555 | return r; | |
1556 | if (r > 0) { | |
1557 | if (rr->nsec3.flags & 1) | |
35ad41d3 | 1558 | optout = true; |
105e1512 | 1559 | |
35ad41d3 TG |
1560 | a = a && (flags & DNS_ANSWER_AUTHENTICATED); |
1561 | ||
1562 | no_closer = true; | |
1563 | } | |
1564 | ||
1c02e7ba | 1565 | r = dns_name_equal(dns_resource_key_name(rr->key), wildcard_domain); |
35ad41d3 TG |
1566 | if (r < 0) |
1567 | return r; | |
1568 | if (r > 0) { | |
1569 | a = a && (flags & DNS_ANSWER_AUTHENTICATED); | |
1570 | ||
1571 | wildcard_rr = rr; | |
1572 | } | |
1573 | ||
1c02e7ba | 1574 | r = dns_name_between(dns_resource_key_name(rr->key), wildcard_domain, next_hashed_domain); |
35ad41d3 TG |
1575 | if (r < 0) |
1576 | return r; | |
1577 | if (r > 0) { | |
1578 | if (rr->nsec3.flags & 1) | |
1579 | /* This only makes sense if we have a wildcard delegation, which is | |
1580 | * very unlikely, see RFC 4592, Section 4.2, but we cannot rely on | |
1581 | * this not happening, so hence cannot simply conclude NXDOMAIN as | |
1582 | * we would wish */ | |
1583 | optout = true; | |
1584 | ||
1585 | a = a && (flags & DNS_ANSWER_AUTHENTICATED); | |
1586 | ||
1587 | no_wildcard = true; | |
105e1512 LP |
1588 | } |
1589 | } | |
1590 | ||
35ad41d3 TG |
1591 | if (wildcard_rr && no_wildcard) |
1592 | return -EBADMSG; | |
1593 | ||
1594 | if (!no_closer) { | |
1595 | *result = DNSSEC_NSEC_NO_RR; | |
35ad41d3 TG |
1596 | return 0; |
1597 | } | |
1598 | ||
1599 | if (wildcard_rr) { | |
1600 | /* A wildcard exists that matches our query. */ | |
1601 | if (optout) | |
1602 | /* This is not specified in any RFC to the best of my knowledge, but | |
1603 | * if the next closer enclosure is covered by an opt-out NSEC3 RR | |
1604 | * it means that we cannot prove that the source of synthesis is | |
1605 | * correct, as there may be a closer match. */ | |
1606 | *result = DNSSEC_NSEC_OPTOUT; | |
1607 | else if (bitmap_isset(wildcard_rr->nsec3.types, key->type)) | |
1608 | *result = DNSSEC_NSEC_FOUND; | |
1609 | else if (bitmap_isset(wildcard_rr->nsec3.types, DNS_TYPE_CNAME)) | |
1610 | *result = DNSSEC_NSEC_CNAME; | |
1611 | else | |
1612 | *result = DNSSEC_NSEC_NODATA; | |
1613 | } else { | |
1614 | if (optout) | |
1615 | /* The RFC only specifies that we have to care for optout for NODATA for | |
1616 | * DS records. However, children of an insecure opt-out delegation should | |
1617 | * also be considered opt-out, rather than verified NXDOMAIN. | |
1618 | * Note that we do not require a proof of wildcard non-existence if the | |
1619 | * next closer domain is covered by an opt-out, as that would not provide | |
1620 | * any additional information. */ | |
1621 | *result = DNSSEC_NSEC_OPTOUT; | |
1622 | else if (no_wildcard) | |
1623 | *result = DNSSEC_NSEC_NXDOMAIN; | |
1624 | else { | |
1625 | *result = DNSSEC_NSEC_NO_RR; | |
1626 | ||
1627 | return 0; | |
1628 | } | |
1629 | } | |
1630 | ||
d3760be0 LP |
1631 | if (authenticated) |
1632 | *authenticated = a; | |
1633 | ||
1634 | if (ttl) | |
1635 | *ttl = enclosure_rr->ttl; | |
35ad41d3 | 1636 | |
105e1512 LP |
1637 | return 0; |
1638 | } | |
1639 | ||
ab481675 LP |
1640 | static int dnssec_nsec_wildcard_equal(DnsResourceRecord *rr, const char *name) { |
1641 | char label[DNS_LABEL_MAX]; | |
1642 | const char *n; | |
1643 | int r; | |
1644 | ||
1645 | assert(rr); | |
1646 | assert(rr->key->type == DNS_TYPE_NSEC); | |
1647 | ||
1648 | /* Checks whether the specified RR has a name beginning in "*.", and if the rest is a suffix of our name */ | |
1649 | ||
1650 | if (rr->n_skip_labels_source != 1) | |
1651 | return 0; | |
1652 | ||
1c02e7ba | 1653 | n = dns_resource_key_name(rr->key); |
7470cc4c | 1654 | r = dns_label_unescape(&n, label, sizeof label, 0); |
ab481675 LP |
1655 | if (r <= 0) |
1656 | return r; | |
1657 | if (r != 1 || label[0] != '*') | |
1658 | return 0; | |
1659 | ||
1660 | return dns_name_endswith(name, n); | |
1661 | } | |
1662 | ||
1663 | static int dnssec_nsec_in_path(DnsResourceRecord *rr, const char *name) { | |
b9282bc1 LP |
1664 | const char *nn, *common_suffix; |
1665 | int r; | |
1666 | ||
1667 | assert(rr); | |
1668 | assert(rr->key->type == DNS_TYPE_NSEC); | |
1669 | ||
1670 | /* Checks whether the specified nsec RR indicates that name is an empty non-terminal (ENT) | |
1671 | * | |
1672 | * A couple of examples: | |
1673 | * | |
1674 | * NSEC bar → waldo.foo.bar: indicates that foo.bar exists and is an ENT | |
1675 | * NSEC waldo.foo.bar → yyy.zzz.xoo.bar: indicates that xoo.bar and zzz.xoo.bar exist and are ENTs | |
1676 | * NSEC yyy.zzz.xoo.bar → bar: indicates pretty much nothing about ENTs | |
1677 | */ | |
1678 | ||
1679 | /* First, determine parent of next domain. */ | |
1680 | nn = rr->nsec.next_domain_name; | |
1681 | r = dns_name_parent(&nn); | |
1682 | if (r <= 0) | |
1683 | return r; | |
1684 | ||
1685 | /* If the name we just determined is not equal or child of the name we are interested in, then we can't say | |
1686 | * anything at all. */ | |
1687 | r = dns_name_endswith(nn, name); | |
1688 | if (r <= 0) | |
1689 | return r; | |
1690 | ||
61233823 | 1691 | /* If the name we are interested in is not a prefix of the common suffix of the NSEC RR's owner and next domain names, then we can't say anything either. */ |
1c02e7ba | 1692 | r = dns_name_common_suffix(dns_resource_key_name(rr->key), rr->nsec.next_domain_name, &common_suffix); |
b9282bc1 LP |
1693 | if (r < 0) |
1694 | return r; | |
1695 | ||
1696 | return dns_name_endswith(name, common_suffix); | |
1697 | } | |
1698 | ||
ab481675 LP |
1699 | static int dnssec_nsec_from_parent_zone(DnsResourceRecord *rr, const char *name) { |
1700 | int r; | |
1701 | ||
1702 | assert(rr); | |
1703 | assert(rr->key->type == DNS_TYPE_NSEC); | |
1704 | ||
1705 | /* Checks whether this NSEC originates to the parent zone or the child zone. */ | |
1706 | ||
1707 | r = dns_name_parent(&name); | |
1708 | if (r <= 0) | |
1709 | return r; | |
1710 | ||
1c02e7ba | 1711 | r = dns_name_equal(name, dns_resource_key_name(rr->key)); |
ab481675 LP |
1712 | if (r <= 0) |
1713 | return r; | |
1714 | ||
1715 | /* DNAME, and NS without SOA is an indication for a delegation. */ | |
1716 | if (bitmap_isset(rr->nsec.types, DNS_TYPE_DNAME)) | |
1717 | return 1; | |
1718 | ||
1719 | if (bitmap_isset(rr->nsec.types, DNS_TYPE_NS) && !bitmap_isset(rr->nsec.types, DNS_TYPE_SOA)) | |
1720 | return 1; | |
1721 | ||
1722 | return 0; | |
1723 | } | |
1724 | ||
1725 | static int dnssec_nsec_covers(DnsResourceRecord *rr, const char *name) { | |
0b491556 | 1726 | const char *signer; |
ab481675 LP |
1727 | int r; |
1728 | ||
1729 | assert(rr); | |
1730 | assert(rr->key->type == DNS_TYPE_NSEC); | |
1731 | ||
0b491556 LP |
1732 | /* Checks whether the name is covered by this NSEC RR. This means, that the name is somewhere below the NSEC's |
1733 | * signer name, and between the NSEC's two names. */ | |
ab481675 | 1734 | |
0b491556 | 1735 | r = dns_resource_record_signer(rr, &signer); |
ab481675 LP |
1736 | if (r < 0) |
1737 | return r; | |
1738 | ||
0b491556 LP |
1739 | r = dns_name_endswith(name, signer); /* this NSEC isn't suitable the name is not in the signer's domain */ |
1740 | if (r <= 0) | |
1741 | return r; | |
ab481675 | 1742 | |
0b491556 | 1743 | return dns_name_between(dns_resource_key_name(rr->key), name, rr->nsec.next_domain_name); |
ab481675 LP |
1744 | } |
1745 | ||
13e6f383 AT |
1746 | static int dnssec_nsec_generate_wildcard(DnsResourceRecord *rr, const char *name, char **wc) { |
1747 | const char *common_suffix1, *common_suffix2, *signer; | |
1748 | int r, labels1, labels2; | |
d86c982a LP |
1749 | |
1750 | assert(rr); | |
1751 | assert(rr->key->type == DNS_TYPE_NSEC); | |
1752 | ||
13e6f383 | 1753 | /* Generates "Wildcard at the Closest Encloser" for the given name and NSEC RR. */ |
d86c982a | 1754 | |
0b491556 | 1755 | r = dns_resource_record_signer(rr, &signer); |
d86c982a LP |
1756 | if (r < 0) |
1757 | return r; | |
1758 | ||
0b491556 | 1759 | r = dns_name_endswith(name, signer); /* this NSEC isn't suitable the name is not in the signer's domain */ |
d86c982a LP |
1760 | if (r <= 0) |
1761 | return r; | |
1762 | ||
13e6f383 | 1763 | r = dns_name_common_suffix(name, dns_resource_key_name(rr->key), &common_suffix1); |
0b491556 LP |
1764 | if (r < 0) |
1765 | return r; | |
0b491556 | 1766 | |
13e6f383 AT |
1767 | r = dns_name_common_suffix(name, rr->nsec.next_domain_name, &common_suffix2); |
1768 | if (r < 0) | |
1769 | return r; | |
1770 | ||
1771 | labels1 = dns_name_count_labels(common_suffix1); | |
1772 | if (labels1 < 0) | |
1773 | return labels1; | |
1774 | ||
1775 | labels2 = dns_name_count_labels(common_suffix2); | |
1776 | if (labels2 < 0) | |
1777 | return labels2; | |
1778 | ||
1779 | if (labels1 > labels2) | |
1780 | r = dns_name_concat("*", common_suffix1, 0, wc); | |
1781 | else | |
1782 | r = dns_name_concat("*", common_suffix2, 0, wc); | |
1783 | ||
97c2ea26 LP |
1784 | if (r < 0) |
1785 | return r; | |
1786 | ||
13e6f383 | 1787 | return 0; |
d86c982a LP |
1788 | } |
1789 | ||
0c7bff0a | 1790 | int dnssec_nsec_test(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) { |
d86c982a LP |
1791 | bool have_nsec3 = false, covering_rr_authenticated = false, wildcard_rr_authenticated = false; |
1792 | DnsResourceRecord *rr, *covering_rr = NULL, *wildcard_rr = NULL; | |
105e1512 | 1793 | DnsAnswerFlags flags; |
b9282bc1 | 1794 | const char *name; |
105e1512 LP |
1795 | int r; |
1796 | ||
1797 | assert(key); | |
1798 | assert(result); | |
1799 | ||
1800 | /* Look for any NSEC/NSEC3 RRs that say something about the specified key. */ | |
1801 | ||
1c02e7ba | 1802 | name = dns_resource_key_name(key); |
b9282bc1 | 1803 | |
105e1512 LP |
1804 | DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) { |
1805 | ||
1806 | if (rr->key->class != key->class) | |
1807 | continue; | |
1808 | ||
ab481675 | 1809 | have_nsec3 = have_nsec3 || (rr->key->type == DNS_TYPE_NSEC3); |
105e1512 | 1810 | |
ab481675 LP |
1811 | if (rr->key->type != DNS_TYPE_NSEC) |
1812 | continue; | |
1813 | ||
1814 | /* The following checks only make sense for NSEC RRs that are not expanded from a wildcard */ | |
1815 | r = dns_resource_record_is_synthetic(rr); | |
2f4c2db2 LP |
1816 | if (r == -ENODATA) /* No signing RR known. */ |
1817 | continue; | |
ab481675 LP |
1818 | if (r < 0) |
1819 | return r; | |
1820 | if (r > 0) | |
1821 | continue; | |
105e1512 | 1822 | |
ab481675 | 1823 | /* Check if this is a direct match. If so, we have encountered a NODATA case */ |
1c02e7ba | 1824 | r = dns_name_equal(dns_resource_key_name(rr->key), name); |
ab481675 LP |
1825 | if (r < 0) |
1826 | return r; | |
1827 | if (r == 0) { | |
1828 | /* If it's not a direct match, maybe it's a wild card match? */ | |
1829 | r = dnssec_nsec_wildcard_equal(rr, name); | |
105e1512 LP |
1830 | if (r < 0) |
1831 | return r; | |
ab481675 LP |
1832 | } |
1833 | if (r > 0) { | |
1834 | if (key->type == DNS_TYPE_DS) { | |
1835 | /* If we look for a DS RR and the server sent us the NSEC RR of the child zone | |
1836 | * we have a problem. For DS RRs we want the NSEC RR from the parent */ | |
1837 | if (bitmap_isset(rr->nsec.types, DNS_TYPE_SOA)) | |
1838 | continue; | |
1839 | } else { | |
1840 | /* For all RR types, ensure that if NS is set SOA is set too, so that we know | |
1841 | * we got the child's NSEC. */ | |
1842 | if (bitmap_isset(rr->nsec.types, DNS_TYPE_NS) && | |
1843 | !bitmap_isset(rr->nsec.types, DNS_TYPE_SOA)) | |
1844 | continue; | |
72667f08 LP |
1845 | } |
1846 | ||
ab481675 LP |
1847 | if (bitmap_isset(rr->nsec.types, key->type)) |
1848 | *result = DNSSEC_NSEC_FOUND; | |
1849 | else if (bitmap_isset(rr->nsec.types, DNS_TYPE_CNAME)) | |
1850 | *result = DNSSEC_NSEC_CNAME; | |
1851 | else | |
b9282bc1 | 1852 | *result = DNSSEC_NSEC_NODATA; |
d3760be0 | 1853 | |
ab481675 LP |
1854 | if (authenticated) |
1855 | *authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
1856 | if (ttl) | |
1857 | *ttl = rr->ttl; | |
d3760be0 | 1858 | |
ab481675 LP |
1859 | return 0; |
1860 | } | |
b9282bc1 | 1861 | |
ab481675 LP |
1862 | /* Check if the name we are looking for is an empty non-terminal within the owner or next name |
1863 | * of the NSEC RR. */ | |
1864 | r = dnssec_nsec_in_path(rr, name); | |
1865 | if (r < 0) | |
1866 | return r; | |
1867 | if (r > 0) { | |
1868 | *result = DNSSEC_NSEC_NODATA; | |
b9282bc1 | 1869 | |
ab481675 LP |
1870 | if (authenticated) |
1871 | *authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
1872 | if (ttl) | |
1873 | *ttl = rr->ttl; | |
b9282bc1 | 1874 | |
ab481675 LP |
1875 | return 0; |
1876 | } | |
72667f08 | 1877 | |
ab481675 LP |
1878 | /* The following two "covering" checks, are not useful if the NSEC is from the parent */ |
1879 | r = dnssec_nsec_from_parent_zone(rr, name); | |
1880 | if (r < 0) | |
1881 | return r; | |
1882 | if (r > 0) | |
1883 | continue; | |
1884 | ||
1885 | /* Check if this NSEC RR proves the absence of an explicit RR under this name */ | |
1886 | r = dnssec_nsec_covers(rr, name); | |
1887 | if (r < 0) | |
1888 | return r; | |
1889 | if (r > 0 && (!covering_rr || !covering_rr_authenticated)) { | |
1890 | covering_rr = rr; | |
1891 | covering_rr_authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
1892 | } | |
13e6f383 | 1893 | } |
ab481675 | 1894 | |
13e6f383 AT |
1895 | if (covering_rr) { |
1896 | _cleanup_free_ char *wc = NULL; | |
1897 | r = dnssec_nsec_generate_wildcard(covering_rr, name, &wc); | |
ab481675 LP |
1898 | if (r < 0) |
1899 | return r; | |
13e6f383 AT |
1900 | |
1901 | DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) { | |
1902 | ||
1903 | if (rr->key->class != key->class) | |
1904 | continue; | |
1905 | ||
1906 | if (rr->key->type != DNS_TYPE_NSEC) | |
1907 | continue; | |
1908 | ||
1909 | /* Check if this NSEC RR proves the nonexistence of the wildcard */ | |
1910 | r = dnssec_nsec_covers(rr, wc); | |
1911 | if (r < 0) | |
1912 | return r; | |
1913 | if (r > 0 && (!wildcard_rr || !wildcard_rr_authenticated)) { | |
1914 | wildcard_rr = rr; | |
1915 | wildcard_rr_authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
1916 | } | |
72667f08 LP |
1917 | } |
1918 | } | |
1919 | ||
d86c982a LP |
1920 | if (covering_rr && wildcard_rr) { |
1921 | /* If we could prove that neither the name itself, nor the wildcard at the closest encloser exists, we | |
1922 | * proved the NXDOMAIN case. */ | |
1923 | *result = DNSSEC_NSEC_NXDOMAIN; | |
1924 | ||
1925 | if (authenticated) | |
1926 | *authenticated = covering_rr_authenticated && wildcard_rr_authenticated; | |
1927 | if (ttl) | |
1928 | *ttl = MIN(covering_rr->ttl, wildcard_rr->ttl); | |
1929 | ||
1930 | return 0; | |
1931 | } | |
1932 | ||
105e1512 LP |
1933 | /* OK, this was not sufficient. Let's see if NSEC3 can help. */ |
1934 | if (have_nsec3) | |
d3760be0 | 1935 | return dnssec_test_nsec3(answer, key, result, authenticated, ttl); |
105e1512 | 1936 | |
5238e957 | 1937 | /* No appropriate NSEC RR found, report this. */ |
72667f08 LP |
1938 | *result = DNSSEC_NSEC_NO_RR; |
1939 | return 0; | |
1940 | } | |
1941 | ||
421cc89d | 1942 | static int dnssec_nsec_test_enclosed(DnsAnswer *answer, uint16_t type, const char *name, const char *zone, bool *authenticated) { |
0c7bff0a LP |
1943 | DnsResourceRecord *rr; |
1944 | DnsAnswerFlags flags; | |
1945 | int r; | |
1946 | ||
1947 | assert(name); | |
1948 | assert(zone); | |
1949 | ||
1950 | /* Checks whether there's an NSEC/NSEC3 that proves that the specified 'name' is non-existing in the specified | |
1951 | * 'zone'. The 'zone' must be a suffix of the 'name'. */ | |
1952 | ||
1953 | DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) { | |
1954 | bool found = false; | |
1955 | ||
e926785a LP |
1956 | if (rr->key->type != type && type != DNS_TYPE_ANY) |
1957 | continue; | |
1958 | ||
0c7bff0a LP |
1959 | switch (rr->key->type) { |
1960 | ||
1961 | case DNS_TYPE_NSEC: | |
97c67192 LP |
1962 | |
1963 | /* We only care for NSEC RRs from the indicated zone */ | |
1964 | r = dns_resource_record_is_signer(rr, zone); | |
1965 | if (r < 0) | |
1966 | return r; | |
1967 | if (r == 0) | |
1968 | continue; | |
1969 | ||
1c02e7ba | 1970 | r = dns_name_between(dns_resource_key_name(rr->key), name, rr->nsec.next_domain_name); |
0c7bff0a LP |
1971 | if (r < 0) |
1972 | return r; | |
1973 | ||
1974 | found = r > 0; | |
1975 | break; | |
1976 | ||
1977 | case DNS_TYPE_NSEC3: { | |
1978 | _cleanup_free_ char *hashed_domain = NULL, *next_hashed_domain = NULL; | |
1979 | ||
97c67192 LP |
1980 | /* We only care for NSEC3 RRs from the indicated zone */ |
1981 | r = dns_resource_record_is_signer(rr, zone); | |
1982 | if (r < 0) | |
1983 | return r; | |
1984 | if (r == 0) | |
1985 | continue; | |
1986 | ||
0c7bff0a LP |
1987 | r = nsec3_is_good(rr, NULL); |
1988 | if (r < 0) | |
1989 | return r; | |
1990 | if (r == 0) | |
1991 | break; | |
1992 | ||
1993 | /* Format the domain we are testing with the NSEC3 RR's hash function */ | |
1994 | r = nsec3_hashed_domain_make( | |
1995 | rr, | |
1996 | name, | |
1997 | zone, | |
1998 | &hashed_domain); | |
1999 | if (r < 0) | |
2000 | return r; | |
2001 | if ((size_t) r != rr->nsec3.next_hashed_name_size) | |
2002 | break; | |
2003 | ||
2004 | /* Format the NSEC3's next hashed name as proper domain name */ | |
2005 | r = nsec3_hashed_domain_format( | |
2006 | rr->nsec3.next_hashed_name, | |
2007 | rr->nsec3.next_hashed_name_size, | |
2008 | zone, | |
2009 | &next_hashed_domain); | |
2010 | if (r < 0) | |
2011 | return r; | |
2012 | ||
1c02e7ba | 2013 | r = dns_name_between(dns_resource_key_name(rr->key), hashed_domain, next_hashed_domain); |
0c7bff0a LP |
2014 | if (r < 0) |
2015 | return r; | |
2016 | ||
2017 | found = r > 0; | |
2018 | break; | |
2019 | } | |
2020 | ||
2021 | default: | |
2022 | continue; | |
2023 | } | |
2024 | ||
2025 | if (found) { | |
2026 | if (authenticated) | |
2027 | *authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
2028 | return 1; | |
2029 | } | |
2030 | } | |
2031 | ||
2032 | return 0; | |
2033 | } | |
2034 | ||
e926785a LP |
2035 | static int dnssec_test_positive_wildcard_nsec3( |
2036 | DnsAnswer *answer, | |
2037 | const char *name, | |
2038 | const char *source, | |
2039 | const char *zone, | |
2040 | bool *authenticated) { | |
2041 | ||
2042 | const char *next_closer = NULL; | |
2043 | int r; | |
2044 | ||
2045 | /* Run a positive NSEC3 wildcard proof. Specifically: | |
2046 | * | |
c629ff58 | 2047 | * A proof that the "next closer" of the generating wildcard does not exist. |
e926785a LP |
2048 | * |
2049 | * Note a key difference between the NSEC3 and NSEC versions of the proof. NSEC RRs don't have to exist for | |
2050 | * empty non-transients. NSEC3 RRs however have to. This means it's sufficient to check if the next closer name | |
2051 | * exists for the NSEC3 RR and we are done. | |
2052 | * | |
2053 | * To prove that a.b.c.d.e.f is rightfully synthesized from a wildcard *.d.e.f all we have to check is that | |
2054 | * c.d.e.f does not exist. */ | |
2055 | ||
2056 | for (;;) { | |
2057 | next_closer = name; | |
2058 | r = dns_name_parent(&name); | |
f20db199 | 2059 | if (r <= 0) |
e926785a | 2060 | return r; |
e926785a LP |
2061 | |
2062 | r = dns_name_equal(name, source); | |
2063 | if (r < 0) | |
2064 | return r; | |
2065 | if (r > 0) | |
2066 | break; | |
2067 | } | |
2068 | ||
2069 | return dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC3, next_closer, zone, authenticated); | |
2070 | } | |
2071 | ||
2072 | static int dnssec_test_positive_wildcard_nsec( | |
2073 | DnsAnswer *answer, | |
2074 | const char *name, | |
2075 | const char *source, | |
2076 | const char *zone, | |
2077 | bool *_authenticated) { | |
2078 | ||
2079 | bool authenticated = true; | |
2080 | int r; | |
2081 | ||
2082 | /* Run a positive NSEC wildcard proof. Specifically: | |
2083 | * | |
2084 | * A proof that there's neither a wildcard name nor a non-wildcard name that is a suffix of the name "name" and | |
2085 | * a prefix of the synthesizing source "source" in the zone "zone". | |
2086 | * | |
2087 | * See RFC 5155, Section 8.8 and RFC 4035, Section 5.3.4 | |
2088 | * | |
2089 | * Note that if we want to prove that a.b.c.d.e.f is rightfully synthesized from a wildcard *.d.e.f, then we | |
2090 | * have to prove that none of the following exist: | |
2091 | * | |
2092 | * 1) a.b.c.d.e.f | |
2093 | * 2) *.b.c.d.e.f | |
2094 | * 3) b.c.d.e.f | |
2095 | * 4) *.c.d.e.f | |
2096 | * 5) c.d.e.f | |
e926785a LP |
2097 | */ |
2098 | ||
2099 | for (;;) { | |
2100 | _cleanup_free_ char *wc = NULL; | |
2101 | bool a = false; | |
2102 | ||
2103 | /* Check if there's an NSEC or NSEC3 RR that proves that the mame we determined is really non-existing, | |
2104 | * i.e between the owner name and the next name of an NSEC RR. */ | |
2105 | r = dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC, name, zone, &a); | |
2106 | if (r <= 0) | |
2107 | return r; | |
2108 | ||
2109 | authenticated = authenticated && a; | |
2110 | ||
2111 | /* Strip one label off */ | |
2112 | r = dns_name_parent(&name); | |
2113 | if (r <= 0) | |
2114 | return r; | |
2115 | ||
2116 | /* Did we reach the source of synthesis? */ | |
2117 | r = dns_name_equal(name, source); | |
2118 | if (r < 0) | |
2119 | return r; | |
2120 | if (r > 0) { | |
2121 | /* Successful exit */ | |
2122 | *_authenticated = authenticated; | |
2123 | return 1; | |
2124 | } | |
2125 | ||
2126 | /* Safety check, that the source of synthesis is still our suffix */ | |
2127 | r = dns_name_endswith(name, source); | |
2128 | if (r < 0) | |
2129 | return r; | |
2130 | if (r == 0) | |
2131 | return -EBADMSG; | |
2132 | ||
2133 | /* Replace the label we stripped off with an asterisk */ | |
b910cc72 | 2134 | wc = strjoin("*.", name); |
e926785a LP |
2135 | if (!wc) |
2136 | return -ENOMEM; | |
2137 | ||
2138 | /* And check if the proof holds for the asterisk name, too */ | |
2139 | r = dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC, wc, zone, &a); | |
2140 | if (r <= 0) | |
2141 | return r; | |
2142 | ||
2143 | authenticated = authenticated && a; | |
2144 | /* In the next iteration we'll check the non-asterisk-prefixed version */ | |
2145 | } | |
2146 | } | |
2147 | ||
2148 | int dnssec_test_positive_wildcard( | |
2149 | DnsAnswer *answer, | |
2150 | const char *name, | |
2151 | const char *source, | |
2152 | const char *zone, | |
2153 | bool *authenticated) { | |
2154 | ||
2155 | int r; | |
2156 | ||
2157 | assert(name); | |
2158 | assert(source); | |
2159 | assert(zone); | |
2160 | assert(authenticated); | |
2161 | ||
2162 | r = dns_answer_contains_zone_nsec3(answer, zone); | |
2163 | if (r < 0) | |
2164 | return r; | |
2165 | if (r > 0) | |
2166 | return dnssec_test_positive_wildcard_nsec3(answer, name, source, zone, authenticated); | |
2167 | else | |
2168 | return dnssec_test_positive_wildcard_nsec(answer, name, source, zone, authenticated); | |
2169 | } | |
2170 | ||
47091522 MO |
2171 | #else |
2172 | ||
2173 | int dnssec_verify_rrset( | |
2174 | DnsAnswer *a, | |
2175 | const DnsResourceKey *key, | |
2176 | DnsResourceRecord *rrsig, | |
2177 | DnsResourceRecord *dnskey, | |
2178 | usec_t realtime, | |
2179 | DnssecResult *result) { | |
2180 | ||
2181 | return -EOPNOTSUPP; | |
2182 | } | |
2183 | ||
2184 | int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, bool revoked_ok) { | |
2185 | ||
2186 | return -EOPNOTSUPP; | |
2187 | } | |
2188 | ||
2189 | int dnssec_key_match_rrsig(const DnsResourceKey *key, DnsResourceRecord *rrsig) { | |
2190 | ||
2191 | return -EOPNOTSUPP; | |
2192 | } | |
2193 | ||
2194 | int dnssec_verify_rrset_search( | |
2195 | DnsAnswer *a, | |
2196 | const DnsResourceKey *key, | |
2197 | DnsAnswer *validated_dnskeys, | |
2198 | usec_t realtime, | |
2199 | DnssecResult *result, | |
2200 | DnsResourceRecord **ret_rrsig) { | |
2201 | ||
2202 | return -EOPNOTSUPP; | |
2203 | } | |
2204 | ||
2205 | int dnssec_has_rrsig(DnsAnswer *a, const DnsResourceKey *key) { | |
2206 | ||
2207 | return -EOPNOTSUPP; | |
2208 | } | |
2209 | ||
2210 | int dnssec_verify_dnskey_by_ds(DnsResourceRecord *dnskey, DnsResourceRecord *ds, bool mask_revoke) { | |
2211 | ||
2212 | return -EOPNOTSUPP; | |
2213 | } | |
2214 | ||
2215 | int dnssec_verify_dnskey_by_ds_search(DnsResourceRecord *dnskey, DnsAnswer *validated_ds) { | |
2216 | ||
2217 | return -EOPNOTSUPP; | |
2218 | } | |
2219 | ||
2220 | int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) { | |
2221 | ||
2222 | return -EOPNOTSUPP; | |
2223 | } | |
2224 | ||
2225 | int dnssec_nsec_test(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) { | |
2226 | ||
2227 | return -EOPNOTSUPP; | |
2228 | } | |
2229 | ||
2230 | int dnssec_test_positive_wildcard( | |
2231 | DnsAnswer *answer, | |
2232 | const char *name, | |
2233 | const char *source, | |
2234 | const char *zone, | |
2235 | bool *authenticated) { | |
2236 | ||
2237 | return -EOPNOTSUPP; | |
2238 | } | |
2239 | ||
2240 | #endif | |
2241 | ||
547973de LP |
2242 | static const char* const dnssec_result_table[_DNSSEC_RESULT_MAX] = { |
2243 | [DNSSEC_VALIDATED] = "validated", | |
0c7bff0a | 2244 | [DNSSEC_VALIDATED_WILDCARD] = "validated-wildcard", |
547973de | 2245 | [DNSSEC_INVALID] = "invalid", |
203f1b35 LP |
2246 | [DNSSEC_SIGNATURE_EXPIRED] = "signature-expired", |
2247 | [DNSSEC_UNSUPPORTED_ALGORITHM] = "unsupported-algorithm", | |
547973de LP |
2248 | [DNSSEC_NO_SIGNATURE] = "no-signature", |
2249 | [DNSSEC_MISSING_KEY] = "missing-key", | |
203f1b35 | 2250 | [DNSSEC_UNSIGNED] = "unsigned", |
547973de | 2251 | [DNSSEC_FAILED_AUXILIARY] = "failed-auxiliary", |
72667f08 | 2252 | [DNSSEC_NSEC_MISMATCH] = "nsec-mismatch", |
b652d4a2 | 2253 | [DNSSEC_INCOMPATIBLE_SERVER] = "incompatible-server", |
547973de LP |
2254 | }; |
2255 | DEFINE_STRING_TABLE_LOOKUP(dnssec_result, DnssecResult); | |
59c5b597 LP |
2256 | |
2257 | static const char* const dnssec_verdict_table[_DNSSEC_VERDICT_MAX] = { | |
2258 | [DNSSEC_SECURE] = "secure", | |
2259 | [DNSSEC_INSECURE] = "insecure", | |
2260 | [DNSSEC_BOGUS] = "bogus", | |
2261 | [DNSSEC_INDETERMINATE] = "indeterminate", | |
2262 | }; | |
2263 | DEFINE_STRING_TABLE_LOOKUP(dnssec_verdict, DnssecVerdict); |