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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" |
2485b7e2 | 10 | #include "memstream-util.h" |
0351cbb9 | 11 | #include "openssl-util.h" |
2b442ac8 LP |
12 | #include "resolved-dns-dnssec.h" |
13 | #include "resolved-dns-packet.h" | |
760877e9 | 14 | #include "sort-util.h" |
24710c48 | 15 | #include "string-table.h" |
2b442ac8 | 16 | |
dcec950c | 17 | #if PREFER_OPENSSL && OPENSSL_VERSION_MAJOR >= 3 |
acfdfb86 ZJS |
18 | # pragma GCC diagnostic push |
19 | # pragma GCC diagnostic ignored "-Wdeprecated-declarations" | |
20 | DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(RSA*, RSA_free, NULL); | |
21 | DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(EC_KEY*, EC_KEY_free, NULL); | |
22 | # pragma GCC diagnostic pop | |
23 | #endif | |
24 | ||
2b442ac8 LP |
25 | #define VERIFY_RRS_MAX 256 |
26 | #define MAX_KEY_SIZE (32*1024) | |
27 | ||
896c5672 LP |
28 | /* Permit a maximum clock skew of 1h 10min. This should be enough to deal with DST confusion */ |
29 | #define SKEW_MAX (1*USEC_PER_HOUR + 10*USEC_PER_MINUTE) | |
30 | ||
eba29112 RP |
31 | /* Maximum number of NSEC3 iterations we'll do. RFC5155 says 2500 shall be the maximum useful value, but |
32 | * RFC9276 § 3.2 says that we should reduce the acceptable iteration count */ | |
33 | #define NSEC3_ITERATIONS_MAX 100 | |
a8f158b9 | 34 | |
2b442ac8 LP |
35 | /* |
36 | * The DNSSEC Chain of trust: | |
37 | * | |
38 | * Normal RRs are protected via RRSIG RRs in combination with DNSKEY RRs, all in the same zone | |
39 | * DNSKEY RRs are either protected like normal RRs, or via a DS from a zone "higher" up the tree | |
40 | * DS RRs are protected like normal RRs | |
41 | * | |
42 | * Example chain: | |
43 | * Normal RR → RRSIG/DNSKEY+ → DS → RRSIG/DNSKEY+ → DS → ... → DS → RRSIG/DNSKEY+ → DS | |
44 | */ | |
45 | ||
0c857028 | 46 | uint16_t dnssec_keytag(DnsResourceRecord *dnskey, bool mask_revoke) { |
2b442ac8 | 47 | const uint8_t *p; |
0c857028 | 48 | uint32_t sum, f; |
2b442ac8 LP |
49 | |
50 | /* The algorithm from RFC 4034, Appendix B. */ | |
51 | ||
52 | assert(dnskey); | |
53 | assert(dnskey->key->type == DNS_TYPE_DNSKEY); | |
54 | ||
0c857028 LP |
55 | f = (uint32_t) dnskey->dnskey.flags; |
56 | ||
57 | if (mask_revoke) | |
58 | f &= ~DNSKEY_FLAG_REVOKE; | |
59 | ||
60 | sum = f + ((((uint32_t) dnskey->dnskey.protocol) << 8) + (uint32_t) dnskey->dnskey.algorithm); | |
2b442ac8 LP |
61 | |
62 | p = dnskey->dnskey.key; | |
63 | ||
6f1d18ae | 64 | for (size_t i = 0; i < dnskey->dnskey.key_size; i++) |
2b442ac8 LP |
65 | sum += (i & 1) == 0 ? (uint32_t) p[i] << 8 : (uint32_t) p[i]; |
66 | ||
67 | sum += (sum >> 16) & UINT32_C(0xFFFF); | |
68 | ||
69 | return sum & UINT32_C(0xFFFF); | |
70 | } | |
71 | ||
0351cbb9 | 72 | #if HAVE_OPENSSL_OR_GCRYPT |
47091522 | 73 | |
93bab288 YW |
74 | static int rr_compare(DnsResourceRecord * const *a, DnsResourceRecord * const *b) { |
75 | const DnsResourceRecord *x = *a, *y = *b; | |
2b442ac8 LP |
76 | size_t m; |
77 | int r; | |
78 | ||
79 | /* Let's order the RRs according to RFC 4034, Section 6.3 */ | |
80 | ||
81 | assert(x); | |
93bab288 | 82 | assert(x->wire_format); |
2b442ac8 | 83 | assert(y); |
93bab288 | 84 | assert(y->wire_format); |
2b442ac8 | 85 | |
93bab288 | 86 | m = MIN(DNS_RESOURCE_RECORD_RDATA_SIZE(x), DNS_RESOURCE_RECORD_RDATA_SIZE(y)); |
2b442ac8 | 87 | |
93bab288 | 88 | r = memcmp(DNS_RESOURCE_RECORD_RDATA(x), DNS_RESOURCE_RECORD_RDATA(y), m); |
2b442ac8 LP |
89 | if (r != 0) |
90 | return r; | |
91 | ||
93bab288 | 92 | return CMP(DNS_RESOURCE_RECORD_RDATA_SIZE(x), DNS_RESOURCE_RECORD_RDATA_SIZE(y)); |
2b442ac8 LP |
93 | } |
94 | ||
ea3a892f | 95 | static int dnssec_rsa_verify_raw( |
0351cbb9 | 96 | hash_algorithm_t hash_algorithm, |
2b442ac8 LP |
97 | const void *signature, size_t signature_size, |
98 | const void *data, size_t data_size, | |
99 | const void *exponent, size_t exponent_size, | |
100 | const void *modulus, size_t modulus_size) { | |
acfdfb86 | 101 | int r; |
2b442ac8 | 102 | |
0351cbb9 | 103 | #if PREFER_OPENSSL |
acfdfb86 ZJS |
104 | # pragma GCC diagnostic push |
105 | # pragma GCC diagnostic ignored "-Wdeprecated-declarations" | |
0351cbb9 KK |
106 | _cleanup_(RSA_freep) RSA *rpubkey = NULL; |
107 | _cleanup_(EVP_PKEY_freep) EVP_PKEY *epubkey = NULL; | |
108 | _cleanup_(EVP_PKEY_CTX_freep) EVP_PKEY_CTX *ctx = NULL; | |
109 | _cleanup_(BN_freep) BIGNUM *e = NULL, *m = NULL; | |
0351cbb9 KK |
110 | |
111 | assert(hash_algorithm); | |
112 | ||
113 | e = BN_bin2bn(exponent, exponent_size, NULL); | |
114 | if (!e) | |
115 | return -EIO; | |
116 | ||
117 | m = BN_bin2bn(modulus, modulus_size, NULL); | |
118 | if (!m) | |
119 | return -EIO; | |
120 | ||
121 | rpubkey = RSA_new(); | |
122 | if (!rpubkey) | |
123 | return -ENOMEM; | |
124 | ||
6e732313 | 125 | if (RSA_set0_key(rpubkey, m, e, NULL) <= 0) |
0351cbb9 | 126 | return -EIO; |
6e732313 | 127 | e = m = NULL; |
0351cbb9 KK |
128 | |
129 | assert((size_t) RSA_size(rpubkey) == signature_size); | |
130 | ||
131 | epubkey = EVP_PKEY_new(); | |
132 | if (!epubkey) | |
133 | return -ENOMEM; | |
134 | ||
135 | if (EVP_PKEY_assign_RSA(epubkey, RSAPublicKey_dup(rpubkey)) <= 0) | |
136 | return -EIO; | |
137 | ||
138 | ctx = EVP_PKEY_CTX_new(epubkey, NULL); | |
139 | if (!ctx) | |
140 | return -ENOMEM; | |
141 | ||
142 | if (EVP_PKEY_verify_init(ctx) <= 0) | |
143 | return -EIO; | |
144 | ||
145 | if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) <= 0) | |
146 | return -EIO; | |
147 | ||
148 | if (EVP_PKEY_CTX_set_signature_md(ctx, hash_algorithm) <= 0) | |
149 | return -EIO; | |
150 | ||
151 | r = EVP_PKEY_verify(ctx, signature, signature_size, data, data_size); | |
152 | if (r < 0) | |
153 | return log_debug_errno(SYNTHETIC_ERRNO(EIO), | |
154 | "Signature verification failed: 0x%lx", ERR_get_error()); | |
155 | ||
acfdfb86 | 156 | # pragma GCC diagnostic pop |
0351cbb9 | 157 | #else |
2b442ac8 LP |
158 | gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; |
159 | gcry_mpi_t n = NULL, e = NULL, s = NULL; | |
160 | gcry_error_t ge; | |
2b442ac8 LP |
161 | |
162 | assert(hash_algorithm); | |
163 | ||
164 | ge = gcry_mpi_scan(&s, GCRYMPI_FMT_USG, signature, signature_size, NULL); | |
165 | if (ge != 0) { | |
166 | r = -EIO; | |
167 | goto finish; | |
168 | } | |
169 | ||
170 | ge = gcry_mpi_scan(&e, GCRYMPI_FMT_USG, exponent, exponent_size, NULL); | |
171 | if (ge != 0) { | |
172 | r = -EIO; | |
173 | goto finish; | |
174 | } | |
175 | ||
176 | ge = gcry_mpi_scan(&n, GCRYMPI_FMT_USG, modulus, modulus_size, NULL); | |
177 | if (ge != 0) { | |
178 | r = -EIO; | |
179 | goto finish; | |
180 | } | |
181 | ||
182 | ge = gcry_sexp_build(&signature_sexp, | |
183 | NULL, | |
184 | "(sig-val (rsa (s %m)))", | |
185 | s); | |
186 | ||
187 | if (ge != 0) { | |
188 | r = -EIO; | |
189 | goto finish; | |
190 | } | |
191 | ||
192 | ge = gcry_sexp_build(&data_sexp, | |
193 | NULL, | |
194 | "(data (flags pkcs1) (hash %s %b))", | |
195 | hash_algorithm, | |
196 | (int) data_size, | |
197 | data); | |
198 | if (ge != 0) { | |
199 | r = -EIO; | |
200 | goto finish; | |
201 | } | |
202 | ||
203 | ge = gcry_sexp_build(&public_key_sexp, | |
204 | NULL, | |
205 | "(public-key (rsa (n %m) (e %m)))", | |
206 | n, | |
207 | e); | |
208 | if (ge != 0) { | |
209 | r = -EIO; | |
210 | goto finish; | |
211 | } | |
212 | ||
213 | ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp); | |
d12bf2bd | 214 | if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE) |
2b442ac8 | 215 | r = 0; |
0351cbb9 KK |
216 | else if (ge != 0) |
217 | r = log_debug_errno(SYNTHETIC_ERRNO(EIO), | |
218 | "RSA signature check failed: %s", gpg_strerror(ge)); | |
219 | else | |
2b442ac8 LP |
220 | r = 1; |
221 | ||
222 | finish: | |
223 | if (e) | |
224 | gcry_mpi_release(e); | |
225 | if (n) | |
226 | gcry_mpi_release(n); | |
227 | if (s) | |
228 | gcry_mpi_release(s); | |
229 | ||
230 | if (public_key_sexp) | |
231 | gcry_sexp_release(public_key_sexp); | |
232 | if (signature_sexp) | |
233 | gcry_sexp_release(signature_sexp); | |
234 | if (data_sexp) | |
235 | gcry_sexp_release(data_sexp); | |
0351cbb9 | 236 | #endif |
acfdfb86 | 237 | return r; |
2b442ac8 LP |
238 | } |
239 | ||
ea3a892f | 240 | static int dnssec_rsa_verify( |
0351cbb9 | 241 | hash_algorithm_t hash_algorithm, |
ea3a892f LP |
242 | const void *hash, size_t hash_size, |
243 | DnsResourceRecord *rrsig, | |
244 | DnsResourceRecord *dnskey) { | |
245 | ||
246 | size_t exponent_size, modulus_size; | |
247 | void *exponent, *modulus; | |
248 | ||
249 | assert(hash_algorithm); | |
250 | assert(hash); | |
251 | assert(hash_size > 0); | |
252 | assert(rrsig); | |
253 | assert(dnskey); | |
254 | ||
255 | if (*(uint8_t*) dnskey->dnskey.key == 0) { | |
256 | /* exponent is > 255 bytes long */ | |
257 | ||
258 | exponent = (uint8_t*) dnskey->dnskey.key + 3; | |
259 | exponent_size = | |
ac04adbe TG |
260 | ((size_t) (((uint8_t*) dnskey->dnskey.key)[1]) << 8) | |
261 | ((size_t) ((uint8_t*) dnskey->dnskey.key)[2]); | |
ea3a892f LP |
262 | |
263 | if (exponent_size < 256) | |
264 | return -EINVAL; | |
265 | ||
266 | if (3 + exponent_size >= dnskey->dnskey.key_size) | |
267 | return -EINVAL; | |
268 | ||
269 | modulus = (uint8_t*) dnskey->dnskey.key + 3 + exponent_size; | |
270 | modulus_size = dnskey->dnskey.key_size - 3 - exponent_size; | |
271 | ||
272 | } else { | |
273 | /* exponent is <= 255 bytes long */ | |
274 | ||
275 | exponent = (uint8_t*) dnskey->dnskey.key + 1; | |
276 | exponent_size = (size_t) ((uint8_t*) dnskey->dnskey.key)[0]; | |
277 | ||
278 | if (exponent_size <= 0) | |
279 | return -EINVAL; | |
280 | ||
281 | if (1 + exponent_size >= dnskey->dnskey.key_size) | |
282 | return -EINVAL; | |
283 | ||
284 | modulus = (uint8_t*) dnskey->dnskey.key + 1 + exponent_size; | |
285 | modulus_size = dnskey->dnskey.key_size - 1 - exponent_size; | |
286 | } | |
287 | ||
288 | return dnssec_rsa_verify_raw( | |
289 | hash_algorithm, | |
290 | rrsig->rrsig.signature, rrsig->rrsig.signature_size, | |
291 | hash, hash_size, | |
292 | exponent, exponent_size, | |
293 | modulus, modulus_size); | |
294 | } | |
295 | ||
e0240c64 | 296 | static int dnssec_ecdsa_verify_raw( |
0351cbb9 KK |
297 | hash_algorithm_t hash_algorithm, |
298 | elliptic_curve_t curve, | |
e0240c64 LP |
299 | const void *signature_r, size_t signature_r_size, |
300 | const void *signature_s, size_t signature_s_size, | |
301 | const void *data, size_t data_size, | |
302 | const void *key, size_t key_size) { | |
acfdfb86 | 303 | int k; |
e0240c64 | 304 | |
0351cbb9 | 305 | #if PREFER_OPENSSL |
acfdfb86 ZJS |
306 | # pragma GCC diagnostic push |
307 | # pragma GCC diagnostic ignored "-Wdeprecated-declarations" | |
0351cbb9 KK |
308 | _cleanup_(EC_GROUP_freep) EC_GROUP *ec_group = NULL; |
309 | _cleanup_(EC_POINT_freep) EC_POINT *p = NULL; | |
310 | _cleanup_(EC_KEY_freep) EC_KEY *eckey = NULL; | |
311 | _cleanup_(BN_CTX_freep) BN_CTX *bctx = NULL; | |
312 | _cleanup_(BN_freep) BIGNUM *r = NULL, *s = NULL; | |
313 | _cleanup_(ECDSA_SIG_freep) ECDSA_SIG *sig = NULL; | |
0351cbb9 KK |
314 | |
315 | assert(hash_algorithm); | |
316 | ||
317 | ec_group = EC_GROUP_new_by_curve_name(curve); | |
318 | if (!ec_group) | |
319 | return -ENOMEM; | |
320 | ||
321 | p = EC_POINT_new(ec_group); | |
322 | if (!p) | |
323 | return -ENOMEM; | |
324 | ||
325 | bctx = BN_CTX_new(); | |
326 | if (!bctx) | |
327 | return -ENOMEM; | |
328 | ||
329 | if (EC_POINT_oct2point(ec_group, p, key, key_size, bctx) <= 0) | |
330 | return -EIO; | |
331 | ||
332 | eckey = EC_KEY_new(); | |
333 | if (!eckey) | |
334 | return -ENOMEM; | |
335 | ||
336 | if (EC_KEY_set_group(eckey, ec_group) <= 0) | |
337 | return -EIO; | |
338 | ||
339 | if (EC_KEY_set_public_key(eckey, p) <= 0) | |
340 | return log_debug_errno(SYNTHETIC_ERRNO(EIO), | |
341 | "EC_POINT_bn2point failed: 0x%lx", ERR_get_error()); | |
342 | ||
343 | assert(EC_KEY_check_key(eckey) == 1); | |
344 | ||
345 | r = BN_bin2bn(signature_r, signature_r_size, NULL); | |
346 | if (!r) | |
347 | return -EIO; | |
348 | ||
349 | s = BN_bin2bn(signature_s, signature_s_size, NULL); | |
350 | if (!s) | |
351 | return -EIO; | |
352 | ||
30fd9a2d | 353 | /* TODO: We should eventually use the EVP API once it supports ECDSA signature verification */ |
0351cbb9 KK |
354 | |
355 | sig = ECDSA_SIG_new(); | |
356 | if (!sig) | |
357 | return -ENOMEM; | |
358 | ||
6e732313 | 359 | if (ECDSA_SIG_set0(sig, r, s) <= 0) |
0351cbb9 | 360 | return -EIO; |
6e732313 | 361 | r = s = NULL; |
0351cbb9 KK |
362 | |
363 | k = ECDSA_do_verify(data, data_size, sig, eckey); | |
364 | if (k < 0) | |
365 | return log_debug_errno(SYNTHETIC_ERRNO(EIO), | |
366 | "Signature verification failed: 0x%lx", ERR_get_error()); | |
367 | ||
acfdfb86 | 368 | # pragma GCC diagnostic pop |
0351cbb9 | 369 | #else |
e0240c64 LP |
370 | gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; |
371 | gcry_mpi_t q = NULL, r = NULL, s = NULL; | |
372 | gcry_error_t ge; | |
e0240c64 LP |
373 | |
374 | assert(hash_algorithm); | |
375 | ||
376 | ge = gcry_mpi_scan(&r, GCRYMPI_FMT_USG, signature_r, signature_r_size, NULL); | |
377 | if (ge != 0) { | |
378 | k = -EIO; | |
379 | goto finish; | |
380 | } | |
381 | ||
382 | ge = gcry_mpi_scan(&s, GCRYMPI_FMT_USG, signature_s, signature_s_size, NULL); | |
383 | if (ge != 0) { | |
384 | k = -EIO; | |
385 | goto finish; | |
386 | } | |
387 | ||
388 | ge = gcry_mpi_scan(&q, GCRYMPI_FMT_USG, key, key_size, NULL); | |
389 | if (ge != 0) { | |
390 | k = -EIO; | |
391 | goto finish; | |
392 | } | |
393 | ||
394 | ge = gcry_sexp_build(&signature_sexp, | |
395 | NULL, | |
396 | "(sig-val (ecdsa (r %m) (s %m)))", | |
397 | r, | |
398 | s); | |
399 | if (ge != 0) { | |
400 | k = -EIO; | |
401 | goto finish; | |
402 | } | |
403 | ||
404 | ge = gcry_sexp_build(&data_sexp, | |
405 | NULL, | |
406 | "(data (flags rfc6979) (hash %s %b))", | |
407 | hash_algorithm, | |
408 | (int) data_size, | |
409 | data); | |
410 | if (ge != 0) { | |
411 | k = -EIO; | |
412 | goto finish; | |
413 | } | |
414 | ||
415 | ge = gcry_sexp_build(&public_key_sexp, | |
416 | NULL, | |
417 | "(public-key (ecc (curve %s) (q %m)))", | |
418 | curve, | |
419 | q); | |
420 | if (ge != 0) { | |
421 | k = -EIO; | |
422 | goto finish; | |
423 | } | |
424 | ||
425 | ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp); | |
426 | if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE) | |
427 | k = 0; | |
428 | else if (ge != 0) { | |
429 | log_debug("ECDSA signature check failed: %s", gpg_strerror(ge)); | |
430 | k = -EIO; | |
431 | } else | |
432 | k = 1; | |
433 | finish: | |
434 | if (r) | |
435 | gcry_mpi_release(r); | |
436 | if (s) | |
437 | gcry_mpi_release(s); | |
438 | if (q) | |
439 | gcry_mpi_release(q); | |
440 | ||
441 | if (public_key_sexp) | |
442 | gcry_sexp_release(public_key_sexp); | |
443 | if (signature_sexp) | |
444 | gcry_sexp_release(signature_sexp); | |
445 | if (data_sexp) | |
446 | gcry_sexp_release(data_sexp); | |
0351cbb9 | 447 | #endif |
acfdfb86 | 448 | return k; |
e0240c64 LP |
449 | } |
450 | ||
451 | static int dnssec_ecdsa_verify( | |
0351cbb9 | 452 | hash_algorithm_t hash_algorithm, |
e0240c64 LP |
453 | int algorithm, |
454 | const void *hash, size_t hash_size, | |
455 | DnsResourceRecord *rrsig, | |
456 | DnsResourceRecord *dnskey) { | |
457 | ||
0351cbb9 | 458 | elliptic_curve_t curve; |
e0240c64 LP |
459 | size_t key_size; |
460 | uint8_t *q; | |
461 | ||
462 | assert(hash); | |
463 | assert(hash_size); | |
464 | assert(rrsig); | |
465 | assert(dnskey); | |
466 | ||
467 | if (algorithm == DNSSEC_ALGORITHM_ECDSAP256SHA256) { | |
0351cbb9 | 468 | curve = OPENSSL_OR_GCRYPT(NID_X9_62_prime256v1, "NIST P-256"); /* NIST P-256 */ |
e0240c64 | 469 | key_size = 32; |
e0240c64 | 470 | } else if (algorithm == DNSSEC_ALGORITHM_ECDSAP384SHA384) { |
0351cbb9 | 471 | curve = OPENSSL_OR_GCRYPT(NID_secp384r1, "NIST P-384"); /* NIST P-384 */ |
e0240c64 | 472 | key_size = 48; |
e0240c64 LP |
473 | } else |
474 | return -EOPNOTSUPP; | |
475 | ||
476 | if (dnskey->dnskey.key_size != key_size * 2) | |
477 | return -EINVAL; | |
478 | ||
479 | if (rrsig->rrsig.signature_size != key_size * 2) | |
480 | return -EINVAL; | |
481 | ||
6e9417f5 | 482 | q = newa(uint8_t, key_size*2 + 1); |
e0240c64 LP |
483 | q[0] = 0x04; /* Prepend 0x04 to indicate an uncompressed key */ |
484 | memcpy(q+1, dnskey->dnskey.key, key_size*2); | |
485 | ||
486 | return dnssec_ecdsa_verify_raw( | |
487 | hash_algorithm, | |
488 | curve, | |
489 | rrsig->rrsig.signature, key_size, | |
490 | (uint8_t*) rrsig->rrsig.signature + key_size, key_size, | |
491 | hash, hash_size, | |
492 | q, key_size*2+1); | |
493 | } | |
494 | ||
cb9eeb06 | 495 | static int dnssec_eddsa_verify_raw( |
0351cbb9 KK |
496 | elliptic_curve_t curve, |
497 | const uint8_t *signature, size_t signature_size, | |
498 | const uint8_t *data, size_t data_size, | |
499 | const uint8_t *key, size_t key_size) { | |
500 | ||
501 | #if PREFER_OPENSSL | |
502 | _cleanup_(EVP_PKEY_freep) EVP_PKEY *evkey = NULL; | |
503 | _cleanup_(EVP_PKEY_CTX_freep) EVP_PKEY_CTX *pctx = NULL; | |
504 | _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = NULL; | |
505 | int r; | |
506 | ||
507 | assert(curve == NID_ED25519); | |
508 | assert(signature_size == key_size * 2); | |
509 | ||
510 | uint8_t *q = newa(uint8_t, signature_size + 1); | |
511 | q[0] = 0x04; /* Prepend 0x04 to indicate an uncompressed key */ | |
512 | memcpy(q+1, signature, signature_size); | |
513 | ||
514 | evkey = EVP_PKEY_new_raw_public_key(EVP_PKEY_ED25519, NULL, key, key_size); | |
515 | if (!evkey) | |
516 | return log_debug_errno(SYNTHETIC_ERRNO(EIO), | |
517 | "EVP_PKEY_new_raw_public_key failed: 0x%lx", ERR_get_error()); | |
cb9eeb06 | 518 | |
0351cbb9 KK |
519 | pctx = EVP_PKEY_CTX_new(evkey, NULL); |
520 | if (!pctx) | |
521 | return -ENOMEM; | |
522 | ||
523 | ctx = EVP_MD_CTX_new(); | |
524 | if (!ctx) | |
525 | return -ENOMEM; | |
526 | ||
527 | /* This prevents EVP_DigestVerifyInit from managing pctx and complicating our free logic. */ | |
528 | EVP_MD_CTX_set_pkey_ctx(ctx, pctx); | |
529 | ||
530 | /* One might be tempted to use EVP_PKEY_verify_init, but see Ed25519(7ssl). */ | |
531 | if (EVP_DigestVerifyInit(ctx, &pctx, NULL, NULL, evkey) <= 0) | |
532 | return -EIO; | |
533 | ||
534 | r = EVP_DigestVerify(ctx, signature, signature_size, data, data_size); | |
535 | if (r < 0) | |
536 | return log_debug_errno(SYNTHETIC_ERRNO(EIO), | |
537 | "Signature verification failed: 0x%lx", ERR_get_error()); | |
538 | ||
539 | return r; | |
540 | ||
541 | #elif GCRYPT_VERSION_NUMBER >= 0x010600 | |
cb9eeb06 MCO |
542 | gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; |
543 | gcry_error_t ge; | |
544 | int k; | |
545 | ||
0351cbb9 KK |
546 | assert(signature_size == key_size * 2); |
547 | ||
cb9eeb06 MCO |
548 | ge = gcry_sexp_build(&signature_sexp, |
549 | NULL, | |
550 | "(sig-val (eddsa (r %b) (s %b)))", | |
0351cbb9 KK |
551 | (int) key_size, |
552 | signature, | |
553 | (int) key_size, | |
554 | signature + key_size); | |
cb9eeb06 MCO |
555 | if (ge != 0) { |
556 | k = -EIO; | |
557 | goto finish; | |
558 | } | |
559 | ||
560 | ge = gcry_sexp_build(&data_sexp, | |
561 | NULL, | |
562 | "(data (flags eddsa) (hash-algo sha512) (value %b))", | |
563 | (int) data_size, | |
564 | data); | |
565 | if (ge != 0) { | |
566 | k = -EIO; | |
567 | goto finish; | |
568 | } | |
569 | ||
570 | ge = gcry_sexp_build(&public_key_sexp, | |
571 | NULL, | |
572 | "(public-key (ecc (curve %s) (flags eddsa) (q %b)))", | |
573 | curve, | |
574 | (int) key_size, | |
575 | key); | |
576 | if (ge != 0) { | |
577 | k = -EIO; | |
578 | goto finish; | |
579 | } | |
580 | ||
581 | ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp); | |
582 | if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE) | |
583 | k = 0; | |
0351cbb9 KK |
584 | else if (ge != 0) |
585 | k = log_debug_errno(SYNTHETIC_ERRNO(EIO), | |
586 | "EdDSA signature check failed: %s", gpg_strerror(ge)); | |
587 | else | |
cb9eeb06 MCO |
588 | k = 1; |
589 | finish: | |
590 | if (public_key_sexp) | |
591 | gcry_sexp_release(public_key_sexp); | |
592 | if (signature_sexp) | |
593 | gcry_sexp_release(signature_sexp); | |
594 | if (data_sexp) | |
595 | gcry_sexp_release(data_sexp); | |
596 | ||
597 | return k; | |
0351cbb9 KK |
598 | #else |
599 | return -EOPNOTSUPP; | |
600 | #endif | |
cb9eeb06 MCO |
601 | } |
602 | ||
603 | static int dnssec_eddsa_verify( | |
604 | int algorithm, | |
605 | const void *data, size_t data_size, | |
606 | DnsResourceRecord *rrsig, | |
607 | DnsResourceRecord *dnskey) { | |
0351cbb9 | 608 | elliptic_curve_t curve; |
cb9eeb06 MCO |
609 | size_t key_size; |
610 | ||
611 | if (algorithm == DNSSEC_ALGORITHM_ED25519) { | |
0351cbb9 | 612 | curve = OPENSSL_OR_GCRYPT(NID_ED25519, "Ed25519"); |
cb9eeb06 MCO |
613 | key_size = 32; |
614 | } else | |
615 | return -EOPNOTSUPP; | |
616 | ||
617 | if (dnskey->dnskey.key_size != key_size) | |
618 | return -EINVAL; | |
619 | ||
620 | if (rrsig->rrsig.signature_size != key_size * 2) | |
621 | return -EINVAL; | |
622 | ||
623 | return dnssec_eddsa_verify_raw( | |
624 | curve, | |
0351cbb9 | 625 | rrsig->rrsig.signature, rrsig->rrsig.signature_size, |
cb9eeb06 MCO |
626 | data, data_size, |
627 | dnskey->dnskey.key, key_size); | |
628 | } | |
cb9eeb06 | 629 | |
1cd7a2c1 KK |
630 | static int md_add_uint8(hash_context_t ctx, uint8_t v) { |
631 | #if PREFER_OPENSSL | |
632 | return EVP_DigestUpdate(ctx, &v, sizeof(v)); | |
633 | #else | |
634 | gcry_md_write(ctx, &v, sizeof(v)); | |
635 | return 0; | |
636 | #endif | |
2b442ac8 LP |
637 | } |
638 | ||
1cd7a2c1 | 639 | static int md_add_uint16(hash_context_t ctx, uint16_t v) { |
2b442ac8 | 640 | v = htobe16(v); |
1cd7a2c1 KK |
641 | #if PREFER_OPENSSL |
642 | return EVP_DigestUpdate(ctx, &v, sizeof(v)); | |
643 | #else | |
644 | gcry_md_write(ctx, &v, sizeof(v)); | |
645 | return 0; | |
646 | #endif | |
2b442ac8 LP |
647 | } |
648 | ||
cb9eeb06 MCO |
649 | static void fwrite_uint8(FILE *fp, uint8_t v) { |
650 | fwrite(&v, sizeof(v), 1, fp); | |
651 | } | |
652 | ||
653 | static void fwrite_uint16(FILE *fp, uint16_t v) { | |
654 | v = htobe16(v); | |
655 | fwrite(&v, sizeof(v), 1, fp); | |
656 | } | |
657 | ||
658 | static void fwrite_uint32(FILE *fp, uint32_t v) { | |
2b442ac8 | 659 | v = htobe32(v); |
cb9eeb06 | 660 | fwrite(&v, sizeof(v), 1, fp); |
2b442ac8 LP |
661 | } |
662 | ||
97c67192 LP |
663 | static int dnssec_rrsig_prepare(DnsResourceRecord *rrsig) { |
664 | int n_key_labels, n_signer_labels; | |
665 | const char *name; | |
666 | int r; | |
667 | ||
98e80bf9 ZJS |
668 | /* Checks whether the specified RRSIG RR is somewhat valid, and initializes the .n_skip_labels_source |
669 | * and .n_skip_labels_signer fields so that we can use them later on. */ | |
97c67192 LP |
670 | |
671 | assert(rrsig); | |
672 | assert(rrsig->key->type == DNS_TYPE_RRSIG); | |
673 | ||
674 | /* Check if this RRSIG RR is already prepared */ | |
98e80bf9 | 675 | if (rrsig->n_skip_labels_source != UINT8_MAX) |
97c67192 LP |
676 | return 0; |
677 | ||
678 | if (rrsig->rrsig.inception > rrsig->rrsig.expiration) | |
679 | return -EINVAL; | |
680 | ||
1c02e7ba | 681 | name = dns_resource_key_name(rrsig->key); |
97c67192 LP |
682 | |
683 | n_key_labels = dns_name_count_labels(name); | |
684 | if (n_key_labels < 0) | |
685 | return n_key_labels; | |
686 | if (rrsig->rrsig.labels > n_key_labels) | |
687 | return -EINVAL; | |
688 | ||
689 | n_signer_labels = dns_name_count_labels(rrsig->rrsig.signer); | |
690 | if (n_signer_labels < 0) | |
691 | return n_signer_labels; | |
692 | if (n_signer_labels > rrsig->rrsig.labels) | |
693 | return -EINVAL; | |
694 | ||
695 | r = dns_name_skip(name, n_key_labels - n_signer_labels, &name); | |
696 | if (r < 0) | |
697 | return r; | |
698 | if (r == 0) | |
699 | return -EINVAL; | |
700 | ||
701 | /* Check if the signer is really a suffix of us */ | |
702 | r = dns_name_equal(name, rrsig->rrsig.signer); | |
703 | if (r < 0) | |
704 | return r; | |
705 | if (r == 0) | |
706 | return -EINVAL; | |
707 | ||
98e80bf9 | 708 | assert(n_key_labels < UINT8_MAX); /* UINT8_MAX/-1 means unsigned. */ |
97c67192 LP |
709 | rrsig->n_skip_labels_source = n_key_labels - rrsig->rrsig.labels; |
710 | rrsig->n_skip_labels_signer = n_key_labels - n_signer_labels; | |
711 | ||
712 | return 0; | |
713 | } | |
714 | ||
2a326321 LP |
715 | static int dnssec_rrsig_expired(DnsResourceRecord *rrsig, usec_t realtime) { |
716 | usec_t expiration, inception, skew; | |
717 | ||
718 | assert(rrsig); | |
719 | assert(rrsig->key->type == DNS_TYPE_RRSIG); | |
720 | ||
721 | if (realtime == USEC_INFINITY) | |
722 | realtime = now(CLOCK_REALTIME); | |
723 | ||
724 | expiration = rrsig->rrsig.expiration * USEC_PER_SEC; | |
725 | inception = rrsig->rrsig.inception * USEC_PER_SEC; | |
726 | ||
5ae5cd40 | 727 | /* Consider inverted validity intervals as expired */ |
2a326321 | 728 | if (inception > expiration) |
5ae5cd40 | 729 | return true; |
2a326321 | 730 | |
896c5672 LP |
731 | /* Permit a certain amount of clock skew of 10% of the valid |
732 | * time range. This takes inspiration from unbound's | |
733 | * resolver. */ | |
2a326321 | 734 | skew = (expiration - inception) / 10; |
896c5672 LP |
735 | if (skew > SKEW_MAX) |
736 | skew = SKEW_MAX; | |
2a326321 LP |
737 | |
738 | if (inception < skew) | |
739 | inception = 0; | |
740 | else | |
741 | inception -= skew; | |
742 | ||
743 | if (expiration + skew < expiration) | |
744 | expiration = USEC_INFINITY; | |
745 | else | |
746 | expiration += skew; | |
747 | ||
748 | return realtime < inception || realtime > expiration; | |
749 | } | |
750 | ||
0351cbb9 | 751 | static hash_md_t algorithm_to_implementation_id(uint8_t algorithm) { |
fbf1a66d | 752 | |
0351cbb9 | 753 | /* Translates a DNSSEC signature algorithm into an openssl/gcrypt digest identifier. |
6af47493 | 754 | * |
0351cbb9 KK |
755 | * Note that we implement all algorithms listed as "Must implement" and "Recommended to Implement" in |
756 | * RFC6944. We don't implement any algorithms that are listed as "Optional" or "Must Not Implement". | |
757 | * Specifically, we do not implement RSAMD5, DSASHA1, DH, DSA-NSEC3-SHA1, and GOST-ECC. */ | |
fbf1a66d LP |
758 | |
759 | switch (algorithm) { | |
760 | ||
761 | case DNSSEC_ALGORITHM_RSASHA1: | |
762 | case DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1: | |
0351cbb9 | 763 | return OPENSSL_OR_GCRYPT(EVP_sha1(), GCRY_MD_SHA1); |
fbf1a66d LP |
764 | |
765 | case DNSSEC_ALGORITHM_RSASHA256: | |
e0240c64 | 766 | case DNSSEC_ALGORITHM_ECDSAP256SHA256: |
0351cbb9 | 767 | return OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256); |
fbf1a66d | 768 | |
e0240c64 | 769 | case DNSSEC_ALGORITHM_ECDSAP384SHA384: |
0351cbb9 | 770 | return OPENSSL_OR_GCRYPT(EVP_sha384(), GCRY_MD_SHA384); |
e0240c64 | 771 | |
fbf1a66d | 772 | case DNSSEC_ALGORITHM_RSASHA512: |
0351cbb9 | 773 | return OPENSSL_OR_GCRYPT(EVP_sha512(), GCRY_MD_SHA512); |
fbf1a66d LP |
774 | |
775 | default: | |
0351cbb9 | 776 | return OPENSSL_OR_GCRYPT(NULL, -EOPNOTSUPP); |
fbf1a66d LP |
777 | } |
778 | } | |
779 | ||
97c67192 LP |
780 | static void dnssec_fix_rrset_ttl( |
781 | DnsResourceRecord *list[], | |
782 | unsigned n, | |
cd2cdba2 | 783 | DnsResourceRecord *rrsig) { |
97c67192 | 784 | |
97c67192 LP |
785 | assert(list); |
786 | assert(n > 0); | |
787 | assert(rrsig); | |
788 | ||
6f1d18ae | 789 | for (unsigned k = 0; k < n; k++) { |
97c67192 LP |
790 | DnsResourceRecord *rr = list[k]; |
791 | ||
792 | /* Pick the TTL as the minimum of the RR's TTL, the | |
793 | * RR's original TTL according to the RRSIG and the | |
794 | * RRSIG's own TTL, see RFC 4035, Section 5.3.3 */ | |
795 | rr->ttl = MIN3(rr->ttl, rrsig->rrsig.original_ttl, rrsig->ttl); | |
796 | rr->expiry = rrsig->rrsig.expiration * USEC_PER_SEC; | |
797 | ||
798 | /* Copy over information about the signer and wildcard source of synthesis */ | |
799 | rr->n_skip_labels_source = rrsig->n_skip_labels_source; | |
800 | rr->n_skip_labels_signer = rrsig->n_skip_labels_signer; | |
801 | } | |
802 | ||
803 | rrsig->expiry = rrsig->rrsig.expiration * USEC_PER_SEC; | |
804 | } | |
805 | ||
cc1ecbaa ZJS |
806 | static int dnssec_rrset_serialize_sig( |
807 | DnsResourceRecord *rrsig, | |
808 | const char *source, | |
809 | DnsResourceRecord **list, | |
810 | size_t list_len, | |
811 | bool wildcard, | |
812 | char **ret_sig_data, | |
813 | size_t *ret_sig_size) { | |
814 | ||
2485b7e2 | 815 | _cleanup_(memstream_done) MemStream m = {}; |
cc1ecbaa ZJS |
816 | uint8_t wire_format_name[DNS_WIRE_FORMAT_HOSTNAME_MAX]; |
817 | DnsResourceRecord *rr; | |
2485b7e2 | 818 | FILE *f; |
cc1ecbaa ZJS |
819 | int r; |
820 | ||
821 | assert(rrsig); | |
822 | assert(source); | |
823 | assert(list || list_len == 0); | |
824 | assert(ret_sig_data); | |
825 | assert(ret_sig_size); | |
826 | ||
2485b7e2 | 827 | f = memstream_init(&m); |
cc1ecbaa ZJS |
828 | if (!f) |
829 | return -ENOMEM; | |
830 | ||
831 | fwrite_uint16(f, rrsig->rrsig.type_covered); | |
832 | fwrite_uint8(f, rrsig->rrsig.algorithm); | |
833 | fwrite_uint8(f, rrsig->rrsig.labels); | |
834 | fwrite_uint32(f, rrsig->rrsig.original_ttl); | |
835 | fwrite_uint32(f, rrsig->rrsig.expiration); | |
836 | fwrite_uint32(f, rrsig->rrsig.inception); | |
837 | fwrite_uint16(f, rrsig->rrsig.key_tag); | |
838 | ||
839 | r = dns_name_to_wire_format(rrsig->rrsig.signer, wire_format_name, sizeof(wire_format_name), true); | |
840 | if (r < 0) | |
841 | return r; | |
842 | fwrite(wire_format_name, 1, r, f); | |
843 | ||
844 | /* Convert the source of synthesis into wire format */ | |
845 | r = dns_name_to_wire_format(source, wire_format_name, sizeof(wire_format_name), true); | |
846 | if (r < 0) | |
847 | return r; | |
848 | ||
849 | for (size_t k = 0; k < list_len; k++) { | |
850 | size_t l; | |
851 | ||
852 | rr = list[k]; | |
853 | ||
854 | /* Hash the source of synthesis. If this is a wildcard, then prefix it with the *. label */ | |
855 | if (wildcard) | |
856 | fwrite((uint8_t[]) { 1, '*'}, sizeof(uint8_t), 2, f); | |
857 | fwrite(wire_format_name, 1, r, f); | |
858 | ||
859 | fwrite_uint16(f, rr->key->type); | |
860 | fwrite_uint16(f, rr->key->class); | |
861 | fwrite_uint32(f, rrsig->rrsig.original_ttl); | |
862 | ||
863 | l = DNS_RESOURCE_RECORD_RDATA_SIZE(rr); | |
864 | assert(l <= 0xFFFF); | |
865 | ||
866 | fwrite_uint16(f, (uint16_t) l); | |
867 | fwrite(DNS_RESOURCE_RECORD_RDATA(rr), 1, l, f); | |
868 | } | |
869 | ||
2485b7e2 | 870 | return memstream_finalize(&m, ret_sig_data, ret_sig_size); |
cc1ecbaa ZJS |
871 | } |
872 | ||
667dac6e ZJS |
873 | static int dnssec_rrset_verify_sig( |
874 | DnsResourceRecord *rrsig, | |
875 | DnsResourceRecord *dnskey, | |
876 | const char *sig_data, | |
877 | size_t sig_size) { | |
878 | ||
879 | assert(rrsig); | |
880 | assert(dnskey); | |
881 | assert(sig_data); | |
882 | assert(sig_size > 0); | |
883 | ||
0351cbb9 KK |
884 | hash_md_t md_algorithm; |
885 | ||
886 | #if PREFER_OPENSSL | |
887 | uint8_t hash[EVP_MAX_MD_SIZE]; | |
888 | unsigned hash_size; | |
889 | #else | |
667dac6e ZJS |
890 | _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL; |
891 | void *hash; | |
892 | size_t hash_size; | |
8707c9b2 | 893 | int r; |
667dac6e | 894 | |
8707c9b2 LB |
895 | r = initialize_libgcrypt(false); |
896 | if (r < 0) | |
897 | return r; | |
0351cbb9 | 898 | #endif |
667dac6e ZJS |
899 | |
900 | switch (rrsig->rrsig.algorithm) { | |
901 | case DNSSEC_ALGORITHM_ED25519: | |
0351cbb9 | 902 | #if PREFER_OPENSSL || GCRYPT_VERSION_NUMBER >= 0x010600 |
667dac6e ZJS |
903 | return dnssec_eddsa_verify( |
904 | rrsig->rrsig.algorithm, | |
905 | sig_data, sig_size, | |
906 | rrsig, | |
907 | dnskey); | |
908 | #endif | |
909 | case DNSSEC_ALGORITHM_ED448: | |
910 | return -EOPNOTSUPP; | |
911 | default: | |
912 | /* OK, the RRs are now in canonical order. Let's calculate the digest */ | |
0351cbb9 KK |
913 | md_algorithm = algorithm_to_implementation_id(rrsig->rrsig.algorithm); |
914 | #if PREFER_OPENSSL | |
915 | if (!md_algorithm) | |
916 | return -EOPNOTSUPP; | |
917 | ||
918 | _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = EVP_MD_CTX_new(); | |
919 | if (!ctx) | |
920 | return -ENOMEM; | |
921 | ||
922 | if (EVP_DigestInit_ex(ctx, md_algorithm, NULL) <= 0) | |
923 | return -EIO; | |
924 | ||
925 | if (EVP_DigestUpdate(ctx, sig_data, sig_size) <= 0) | |
926 | return -EIO; | |
927 | ||
928 | if (EVP_DigestFinal_ex(ctx, hash, &hash_size) <= 0) | |
929 | return -EIO; | |
930 | ||
931 | assert(hash_size > 0); | |
932 | ||
933 | #else | |
667dac6e ZJS |
934 | if (md_algorithm < 0) |
935 | return md_algorithm; | |
936 | ||
937 | gcry_error_t err = gcry_md_open(&md, md_algorithm, 0); | |
938 | if (gcry_err_code(err) != GPG_ERR_NO_ERROR || !md) | |
939 | return -EIO; | |
940 | ||
941 | hash_size = gcry_md_get_algo_dlen(md_algorithm); | |
942 | assert(hash_size > 0); | |
943 | ||
944 | gcry_md_write(md, sig_data, sig_size); | |
945 | ||
946 | hash = gcry_md_read(md, 0); | |
947 | if (!hash) | |
948 | return -EIO; | |
0351cbb9 | 949 | #endif |
667dac6e ZJS |
950 | } |
951 | ||
952 | switch (rrsig->rrsig.algorithm) { | |
953 | ||
954 | case DNSSEC_ALGORITHM_RSASHA1: | |
955 | case DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1: | |
956 | case DNSSEC_ALGORITHM_RSASHA256: | |
957 | case DNSSEC_ALGORITHM_RSASHA512: | |
958 | return dnssec_rsa_verify( | |
0351cbb9 | 959 | OPENSSL_OR_GCRYPT(md_algorithm, gcry_md_algo_name(md_algorithm)), |
667dac6e ZJS |
960 | hash, hash_size, |
961 | rrsig, | |
962 | dnskey); | |
963 | ||
964 | case DNSSEC_ALGORITHM_ECDSAP256SHA256: | |
965 | case DNSSEC_ALGORITHM_ECDSAP384SHA384: | |
966 | return dnssec_ecdsa_verify( | |
0351cbb9 | 967 | OPENSSL_OR_GCRYPT(md_algorithm, gcry_md_algo_name(md_algorithm)), |
667dac6e ZJS |
968 | rrsig->rrsig.algorithm, |
969 | hash, hash_size, | |
970 | rrsig, | |
971 | dnskey); | |
972 | ||
973 | default: | |
974 | assert_not_reached(); | |
975 | } | |
976 | } | |
977 | ||
2a326321 LP |
978 | int dnssec_verify_rrset( |
979 | DnsAnswer *a, | |
0c857028 | 980 | const DnsResourceKey *key, |
2a326321 LP |
981 | DnsResourceRecord *rrsig, |
982 | DnsResourceRecord *dnskey, | |
547973de LP |
983 | usec_t realtime, |
984 | DnssecResult *result) { | |
2a326321 | 985 | |
2b442ac8 | 986 | DnsResourceRecord **list, *rr; |
588c53d0 | 987 | const char *source, *name; |
cb9eeb06 | 988 | _cleanup_free_ char *sig_data = NULL; |
d1b8e56a YW |
989 | size_t sig_size = 0; /* avoid false maybe-uninitialized warning */ |
990 | size_t n = 0; | |
7715f91d | 991 | bool wildcard; |
667dac6e | 992 | int r; |
2b442ac8 LP |
993 | |
994 | assert(key); | |
995 | assert(rrsig); | |
996 | assert(dnskey); | |
547973de | 997 | assert(result); |
2a326321 LP |
998 | assert(rrsig->key->type == DNS_TYPE_RRSIG); |
999 | assert(dnskey->key->type == DNS_TYPE_DNSKEY); | |
2b442ac8 | 1000 | |
c629ff58 | 1001 | /* Verifies that the RRSet matches the specified "key" in "a", |
2b442ac8 | 1002 | * using the signature "rrsig" and the key "dnskey". It's |
c629ff58 | 1003 | * assumed that RRSIG and DNSKEY match. */ |
2b442ac8 | 1004 | |
97c67192 LP |
1005 | r = dnssec_rrsig_prepare(rrsig); |
1006 | if (r == -EINVAL) { | |
1007 | *result = DNSSEC_INVALID; | |
1008 | return r; | |
1009 | } | |
1010 | if (r < 0) | |
1011 | return r; | |
1012 | ||
2a326321 LP |
1013 | r = dnssec_rrsig_expired(rrsig, realtime); |
1014 | if (r < 0) | |
1015 | return r; | |
547973de LP |
1016 | if (r > 0) { |
1017 | *result = DNSSEC_SIGNATURE_EXPIRED; | |
1018 | return 0; | |
1019 | } | |
2a326321 | 1020 | |
1c02e7ba | 1021 | name = dns_resource_key_name(key); |
588c53d0 LP |
1022 | |
1023 | /* Some keys may only appear signed in the zone apex, and are invalid anywhere else. (SOA, NS...) */ | |
1024 | if (dns_type_apex_only(rrsig->rrsig.type_covered)) { | |
1025 | r = dns_name_equal(rrsig->rrsig.signer, name); | |
1026 | if (r < 0) | |
1027 | return r; | |
1028 | if (r == 0) { | |
1029 | *result = DNSSEC_INVALID; | |
1030 | return 0; | |
1031 | } | |
1032 | } | |
1033 | ||
1034 | /* OTOH DS RRs may not appear in the zone apex, but are valid everywhere else. */ | |
1035 | if (rrsig->rrsig.type_covered == DNS_TYPE_DS) { | |
1036 | r = dns_name_equal(rrsig->rrsig.signer, name); | |
1037 | if (r < 0) | |
1038 | return r; | |
1039 | if (r > 0) { | |
1040 | *result = DNSSEC_INVALID; | |
1041 | return 0; | |
1042 | } | |
1043 | } | |
1044 | ||
7715f91d | 1045 | /* Determine the "Source of Synthesis" and whether this is a wildcard RRSIG */ |
588c53d0 | 1046 | r = dns_name_suffix(name, rrsig->rrsig.labels, &source); |
7715f91d LP |
1047 | if (r < 0) |
1048 | return r; | |
e8233bce LP |
1049 | if (r > 0 && !dns_type_may_wildcard(rrsig->rrsig.type_covered)) { |
1050 | /* We refuse to validate NSEC3 or SOA RRs that are synthesized from wildcards */ | |
1051 | *result = DNSSEC_INVALID; | |
1052 | return 0; | |
1053 | } | |
7160eb1b LP |
1054 | if (r == 1) { |
1055 | /* If we stripped a single label, then let's see if that maybe was "*". If so, we are not really | |
1056 | * synthesized from a wildcard, we are the wildcard itself. Treat that like a normal name. */ | |
588c53d0 | 1057 | r = dns_name_startswith(name, "*"); |
7160eb1b LP |
1058 | if (r < 0) |
1059 | return r; | |
1060 | if (r > 0) | |
588c53d0 | 1061 | source = name; |
7160eb1b LP |
1062 | |
1063 | wildcard = r == 0; | |
1064 | } else | |
1065 | wildcard = r > 0; | |
7715f91d | 1066 | |
2b442ac8 | 1067 | /* Collect all relevant RRs in a single array, so that we can look at the RRset */ |
0f23174c | 1068 | list = newa(DnsResourceRecord *, dns_answer_size(a)); |
2b442ac8 LP |
1069 | |
1070 | DNS_ANSWER_FOREACH(rr, a) { | |
1071 | r = dns_resource_key_equal(key, rr->key); | |
1072 | if (r < 0) | |
1073 | return r; | |
1074 | if (r == 0) | |
1075 | continue; | |
1076 | ||
1077 | /* We need the wire format for ordering, and digest calculation */ | |
1078 | r = dns_resource_record_to_wire_format(rr, true); | |
1079 | if (r < 0) | |
1080 | return r; | |
1081 | ||
1082 | list[n++] = rr; | |
935a999f TG |
1083 | |
1084 | if (n > VERIFY_RRS_MAX) | |
1085 | return -E2BIG; | |
2b442ac8 LP |
1086 | } |
1087 | ||
1088 | if (n <= 0) | |
1089 | return -ENODATA; | |
1090 | ||
1091 | /* Bring the RRs into canonical order */ | |
93bab288 | 1092 | typesafe_qsort(list, n, rr_compare); |
2b442ac8 | 1093 | |
cc1ecbaa ZJS |
1094 | r = dnssec_rrset_serialize_sig(rrsig, source, list, n, wildcard, |
1095 | &sig_data, &sig_size); | |
cb9eeb06 MCO |
1096 | if (r < 0) |
1097 | return r; | |
1098 | ||
667dac6e ZJS |
1099 | r = dnssec_rrset_verify_sig(rrsig, dnskey, sig_data, sig_size); |
1100 | if (r == -EOPNOTSUPP) { | |
cb9eeb06 | 1101 | *result = DNSSEC_UNSUPPORTED_ALGORITHM; |
8530efc1 | 1102 | return 0; |
e0240c64 | 1103 | } |
2b442ac8 | 1104 | if (r < 0) |
8530efc1 | 1105 | return r; |
2b442ac8 | 1106 | |
97c67192 LP |
1107 | /* Now, fix the ttl, expiry, and remember the synthesizing source and the signer */ |
1108 | if (r > 0) | |
cd2cdba2 | 1109 | dnssec_fix_rrset_ttl(list, n, rrsig); |
97c67192 LP |
1110 | |
1111 | if (r == 0) | |
0c7bff0a LP |
1112 | *result = DNSSEC_INVALID; |
1113 | else if (wildcard) | |
1114 | *result = DNSSEC_VALIDATED_WILDCARD; | |
1115 | else | |
1116 | *result = DNSSEC_VALIDATED; | |
97c67192 | 1117 | |
8530efc1 | 1118 | return 0; |
2b442ac8 LP |
1119 | } |
1120 | ||
0c857028 | 1121 | int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, bool revoked_ok) { |
2b442ac8 LP |
1122 | |
1123 | assert(rrsig); | |
1124 | assert(dnskey); | |
1125 | ||
1126 | /* Checks if the specified DNSKEY RR matches the key used for | |
1127 | * the signature in the specified RRSIG RR */ | |
1128 | ||
1129 | if (rrsig->key->type != DNS_TYPE_RRSIG) | |
1130 | return -EINVAL; | |
1131 | ||
1132 | if (dnskey->key->type != DNS_TYPE_DNSKEY) | |
1133 | return 0; | |
1134 | if (dnskey->key->class != rrsig->key->class) | |
1135 | return 0; | |
1136 | if ((dnskey->dnskey.flags & DNSKEY_FLAG_ZONE_KEY) == 0) | |
1137 | return 0; | |
0c857028 | 1138 | if (!revoked_ok && (dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE)) |
28b8191e | 1139 | return 0; |
2b442ac8 LP |
1140 | if (dnskey->dnskey.protocol != 3) |
1141 | return 0; | |
1142 | if (dnskey->dnskey.algorithm != rrsig->rrsig.algorithm) | |
1143 | return 0; | |
1144 | ||
0c857028 | 1145 | if (dnssec_keytag(dnskey, false) != rrsig->rrsig.key_tag) |
2b442ac8 LP |
1146 | return 0; |
1147 | ||
1c02e7ba | 1148 | return dns_name_equal(dns_resource_key_name(dnskey->key), rrsig->rrsig.signer); |
2b442ac8 LP |
1149 | } |
1150 | ||
105e1512 | 1151 | int dnssec_key_match_rrsig(const DnsResourceKey *key, DnsResourceRecord *rrsig) { |
2b442ac8 LP |
1152 | assert(key); |
1153 | assert(rrsig); | |
1154 | ||
1155 | /* Checks if the specified RRSIG RR protects the RRSet of the specified RR key. */ | |
1156 | ||
1157 | if (rrsig->key->type != DNS_TYPE_RRSIG) | |
1158 | return 0; | |
1159 | if (rrsig->key->class != key->class) | |
1160 | return 0; | |
1161 | if (rrsig->rrsig.type_covered != key->type) | |
1162 | return 0; | |
1163 | ||
1c02e7ba | 1164 | return dns_name_equal(dns_resource_key_name(rrsig->key), dns_resource_key_name(key)); |
2b442ac8 LP |
1165 | } |
1166 | ||
2a326321 LP |
1167 | int dnssec_verify_rrset_search( |
1168 | DnsAnswer *a, | |
0c857028 | 1169 | const DnsResourceKey *key, |
2a326321 | 1170 | DnsAnswer *validated_dnskeys, |
547973de | 1171 | usec_t realtime, |
0c7bff0a LP |
1172 | DnssecResult *result, |
1173 | DnsResourceRecord **ret_rrsig) { | |
2a326321 | 1174 | |
203f1b35 | 1175 | bool found_rrsig = false, found_invalid = false, found_expired_rrsig = false, found_unsupported_algorithm = false; |
67d0ce88 | 1176 | unsigned nvalidations = 0; |
2b442ac8 LP |
1177 | DnsResourceRecord *rrsig; |
1178 | int r; | |
1179 | ||
1180 | assert(key); | |
547973de | 1181 | assert(result); |
2b442ac8 | 1182 | |
105e1512 | 1183 | /* Verifies all RRs from "a" that match the key "key" against DNSKEYs in "validated_dnskeys" */ |
2b442ac8 | 1184 | |
6edf21db | 1185 | if (dns_answer_isempty(a)) |
2b442ac8 LP |
1186 | return -ENODATA; |
1187 | ||
1188 | /* Iterate through each RRSIG RR. */ | |
1189 | DNS_ANSWER_FOREACH(rrsig, a) { | |
1190 | DnsResourceRecord *dnskey; | |
105e1512 | 1191 | DnsAnswerFlags flags; |
2b442ac8 | 1192 | |
203f1b35 | 1193 | /* Is this an RRSIG RR that applies to RRs matching our key? */ |
2b442ac8 LP |
1194 | r = dnssec_key_match_rrsig(key, rrsig); |
1195 | if (r < 0) | |
1196 | return r; | |
1197 | if (r == 0) | |
1198 | continue; | |
1199 | ||
1200 | found_rrsig = true; | |
1201 | ||
547973de | 1202 | /* Look for a matching key */ |
105e1512 | 1203 | DNS_ANSWER_FOREACH_FLAGS(dnskey, flags, validated_dnskeys) { |
547973de | 1204 | DnssecResult one_result; |
2b442ac8 | 1205 | |
105e1512 LP |
1206 | if ((flags & DNS_ANSWER_AUTHENTICATED) == 0) |
1207 | continue; | |
1208 | ||
203f1b35 | 1209 | /* Is this a DNSKEY RR that matches they key of our RRSIG? */ |
0c857028 | 1210 | r = dnssec_rrsig_match_dnskey(rrsig, dnskey, false); |
2b442ac8 LP |
1211 | if (r < 0) |
1212 | return r; | |
1213 | if (r == 0) | |
1214 | continue; | |
1215 | ||
2a326321 LP |
1216 | /* Take the time here, if it isn't set yet, so |
1217 | * that we do all validations with the same | |
1218 | * time. */ | |
1219 | if (realtime == USEC_INFINITY) | |
1220 | realtime = now(CLOCK_REALTIME); | |
1221 | ||
67d0ce88 RP |
1222 | /* Have we seen an unreasonable number of invalid signaures? */ |
1223 | if (nvalidations > DNSSEC_INVALID_MAX) { | |
1224 | if (ret_rrsig) | |
1225 | *ret_rrsig = NULL; | |
1226 | *result = DNSSEC_TOO_MANY_VALIDATIONS; | |
1227 | return (int) nvalidations; | |
1228 | } | |
1229 | ||
2b442ac8 LP |
1230 | /* Yay, we found a matching RRSIG with a matching |
1231 | * DNSKEY, awesome. Now let's verify all entries of | |
1232 | * the RRSet against the RRSIG and DNSKEY | |
1233 | * combination. */ | |
1234 | ||
547973de | 1235 | r = dnssec_verify_rrset(a, key, rrsig, dnskey, realtime, &one_result); |
203f1b35 | 1236 | if (r < 0) |
2b442ac8 | 1237 | return r; |
203f1b35 | 1238 | |
67d0ce88 RP |
1239 | nvalidations++; |
1240 | ||
203f1b35 LP |
1241 | switch (one_result) { |
1242 | ||
1243 | case DNSSEC_VALIDATED: | |
0c7bff0a | 1244 | case DNSSEC_VALIDATED_WILDCARD: |
203f1b35 | 1245 | /* Yay, the RR has been validated, |
ee3d6aff | 1246 | * return immediately, but fix up the expiry */ |
0c7bff0a LP |
1247 | if (ret_rrsig) |
1248 | *ret_rrsig = rrsig; | |
1249 | ||
1250 | *result = one_result; | |
67d0ce88 | 1251 | return (int) nvalidations; |
2b442ac8 | 1252 | |
203f1b35 LP |
1253 | case DNSSEC_INVALID: |
1254 | /* If the signature is invalid, let's try another | |
1255 | key and/or signature. After all they | |
1256 | key_tags and stuff are not unique, and | |
1257 | might be shared by multiple keys. */ | |
1258 | found_invalid = true; | |
1259 | continue; | |
1260 | ||
1261 | case DNSSEC_UNSUPPORTED_ALGORITHM: | |
1262 | /* If the key algorithm is | |
1263 | unsupported, try another | |
1264 | RRSIG/DNSKEY pair, but remember we | |
1265 | encountered this, so that we can | |
1266 | return a proper error when we | |
1267 | encounter nothing better. */ | |
1268 | found_unsupported_algorithm = true; | |
1269 | continue; | |
1270 | ||
1271 | case DNSSEC_SIGNATURE_EXPIRED: | |
1272 | /* If the signature is expired, try | |
1273 | another one, but remember it, so | |
1274 | that we can return this */ | |
1275 | found_expired_rrsig = true; | |
1276 | continue; | |
1277 | ||
1278 | default: | |
04499a70 | 1279 | assert_not_reached(); |
203f1b35 | 1280 | } |
2b442ac8 LP |
1281 | } |
1282 | } | |
1283 | ||
203f1b35 LP |
1284 | if (found_expired_rrsig) |
1285 | *result = DNSSEC_SIGNATURE_EXPIRED; | |
1286 | else if (found_unsupported_algorithm) | |
1287 | *result = DNSSEC_UNSUPPORTED_ALGORITHM; | |
1288 | else if (found_invalid) | |
547973de LP |
1289 | *result = DNSSEC_INVALID; |
1290 | else if (found_rrsig) | |
1291 | *result = DNSSEC_MISSING_KEY; | |
1292 | else | |
1293 | *result = DNSSEC_NO_SIGNATURE; | |
2b442ac8 | 1294 | |
0c7bff0a LP |
1295 | if (ret_rrsig) |
1296 | *ret_rrsig = NULL; | |
1297 | ||
67d0ce88 | 1298 | return (int) nvalidations; |
2b442ac8 LP |
1299 | } |
1300 | ||
105e1512 LP |
1301 | int dnssec_has_rrsig(DnsAnswer *a, const DnsResourceKey *key) { |
1302 | DnsResourceRecord *rr; | |
1303 | int r; | |
1304 | ||
5238e957 | 1305 | /* Checks whether there's at least one RRSIG in 'a' that protects RRs of the specified key */ |
105e1512 LP |
1306 | |
1307 | DNS_ANSWER_FOREACH(rr, a) { | |
1308 | r = dnssec_key_match_rrsig(key, rr); | |
1309 | if (r < 0) | |
1310 | return r; | |
1311 | if (r > 0) | |
1312 | return 1; | |
1313 | } | |
1314 | ||
1315 | return 0; | |
1316 | } | |
1317 | ||
1cd7a2c1 | 1318 | static hash_md_t digest_to_hash_md(uint8_t algorithm) { |
a1972a91 | 1319 | |
1cd7a2c1 | 1320 | /* Translates a DNSSEC digest algorithm into an openssl/gcrypt digest identifier */ |
a1972a91 LP |
1321 | |
1322 | switch (algorithm) { | |
1323 | ||
1324 | case DNSSEC_DIGEST_SHA1: | |
1cd7a2c1 | 1325 | return OPENSSL_OR_GCRYPT(EVP_sha1(), GCRY_MD_SHA1); |
a1972a91 LP |
1326 | |
1327 | case DNSSEC_DIGEST_SHA256: | |
1cd7a2c1 | 1328 | return OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256); |
a1972a91 | 1329 | |
af22c65b | 1330 | case DNSSEC_DIGEST_SHA384: |
1cd7a2c1 | 1331 | return OPENSSL_OR_GCRYPT(EVP_sha384(), GCRY_MD_SHA384); |
af22c65b | 1332 | |
a1972a91 | 1333 | default: |
1cd7a2c1 | 1334 | return OPENSSL_OR_GCRYPT(NULL, -EOPNOTSUPP); |
a1972a91 LP |
1335 | } |
1336 | } | |
1337 | ||
96bb7673 | 1338 | int dnssec_verify_dnskey_by_ds(DnsResourceRecord *dnskey, DnsResourceRecord *ds, bool mask_revoke) { |
5e55cde9 | 1339 | uint8_t wire_format[DNS_WIRE_FORMAT_HOSTNAME_MAX]; |
72270f29 | 1340 | size_t encoded_length; |
1cd7a2c1 | 1341 | int r; |
2b442ac8 LP |
1342 | |
1343 | assert(dnskey); | |
1344 | assert(ds); | |
1345 | ||
1346 | /* Implements DNSKEY verification by a DS, according to RFC 4035, section 5.2 */ | |
1347 | ||
1348 | if (dnskey->key->type != DNS_TYPE_DNSKEY) | |
1349 | return -EINVAL; | |
1350 | if (ds->key->type != DNS_TYPE_DS) | |
1351 | return -EINVAL; | |
1352 | if ((dnskey->dnskey.flags & DNSKEY_FLAG_ZONE_KEY) == 0) | |
1353 | return -EKEYREJECTED; | |
0c857028 LP |
1354 | if (!mask_revoke && (dnskey->dnskey.flags & DNSKEY_FLAG_REVOKE)) |
1355 | return -EKEYREJECTED; | |
2b442ac8 LP |
1356 | if (dnskey->dnskey.protocol != 3) |
1357 | return -EKEYREJECTED; | |
1358 | ||
2b442ac8 LP |
1359 | if (dnskey->dnskey.algorithm != ds->ds.algorithm) |
1360 | return 0; | |
0c857028 | 1361 | if (dnssec_keytag(dnskey, mask_revoke) != ds->ds.key_tag) |
2b442ac8 LP |
1362 | return 0; |
1363 | ||
1cd7a2c1 KK |
1364 | r = dns_name_to_wire_format(dns_resource_key_name(dnskey->key), wire_format, sizeof wire_format, true); |
1365 | if (r < 0) | |
1366 | return r; | |
72270f29 | 1367 | encoded_length = r; |
0638401a | 1368 | |
1cd7a2c1 | 1369 | hash_md_t md_algorithm = digest_to_hash_md(ds->ds.digest_type); |
2b442ac8 | 1370 | |
1cd7a2c1 KK |
1371 | #if PREFER_OPENSSL |
1372 | if (!md_algorithm) | |
1373 | return -EOPNOTSUPP; | |
1374 | ||
1375 | _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = NULL; | |
1376 | uint8_t result[EVP_MAX_MD_SIZE]; | |
1377 | ||
1378 | unsigned hash_size = EVP_MD_size(md_algorithm); | |
a1972a91 | 1379 | assert(hash_size > 0); |
2b442ac8 | 1380 | |
a1972a91 LP |
1381 | if (ds->ds.digest_size != hash_size) |
1382 | return 0; | |
2b442ac8 | 1383 | |
1cd7a2c1 KK |
1384 | ctx = EVP_MD_CTX_new(); |
1385 | if (!ctx) | |
1386 | return -ENOMEM; | |
1387 | ||
1388 | if (EVP_DigestInit_ex(ctx, md_algorithm, NULL) <= 0) | |
1389 | return -EIO; | |
1390 | ||
72270f29 | 1391 | if (EVP_DigestUpdate(ctx, wire_format, encoded_length) <= 0) |
1cd7a2c1 KK |
1392 | return -EIO; |
1393 | ||
1394 | if (mask_revoke) | |
1395 | md_add_uint16(ctx, dnskey->dnskey.flags & ~DNSKEY_FLAG_REVOKE); | |
1396 | else | |
1397 | md_add_uint16(ctx, dnskey->dnskey.flags); | |
1398 | ||
1399 | r = md_add_uint8(ctx, dnskey->dnskey.protocol); | |
1400 | if (r <= 0) | |
a1972a91 | 1401 | return r; |
1cd7a2c1 KK |
1402 | r = md_add_uint8(ctx, dnskey->dnskey.algorithm); |
1403 | if (r <= 0) | |
1404 | return r; | |
1405 | if (EVP_DigestUpdate(ctx, dnskey->dnskey.key, dnskey->dnskey.key_size) <= 0) | |
1406 | return -EIO; | |
1407 | ||
1408 | if (EVP_DigestFinal_ex(ctx, result, NULL) <= 0) | |
1409 | return -EIO; | |
1410 | ||
1411 | #else | |
1412 | if (md_algorithm < 0) | |
1413 | return -EOPNOTSUPP; | |
1414 | ||
8707c9b2 LB |
1415 | r = initialize_libgcrypt(false); |
1416 | if (r < 0) | |
1417 | return r; | |
e28df392 | 1418 | |
1cd7a2c1 | 1419 | _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL; |
2b442ac8 | 1420 | |
1cd7a2c1 KK |
1421 | size_t hash_size = gcry_md_get_algo_dlen(md_algorithm); |
1422 | assert(hash_size > 0); | |
1423 | ||
1424 | if (ds->ds.digest_size != hash_size) | |
1425 | return 0; | |
1426 | ||
1427 | gcry_error_t err = gcry_md_open(&md, md_algorithm, 0); | |
248b1e0a | 1428 | if (gcry_err_code(err) != GPG_ERR_NO_ERROR || !md) |
2b442ac8 LP |
1429 | return -EIO; |
1430 | ||
72270f29 | 1431 | gcry_md_write(md, wire_format, encoded_length); |
0c857028 LP |
1432 | if (mask_revoke) |
1433 | md_add_uint16(md, dnskey->dnskey.flags & ~DNSKEY_FLAG_REVOKE); | |
1434 | else | |
1435 | md_add_uint16(md, dnskey->dnskey.flags); | |
2b442ac8 LP |
1436 | md_add_uint8(md, dnskey->dnskey.protocol); |
1437 | md_add_uint8(md, dnskey->dnskey.algorithm); | |
1438 | gcry_md_write(md, dnskey->dnskey.key, dnskey->dnskey.key_size); | |
1439 | ||
1cd7a2c1 | 1440 | void *result = gcry_md_read(md, 0); |
15c53310 ZJS |
1441 | if (!result) |
1442 | return -EIO; | |
1cd7a2c1 | 1443 | #endif |
2b442ac8 | 1444 | |
c910c520 | 1445 | return memcmp(result, ds->ds.digest, ds->ds.digest_size) == 0; |
2b442ac8 | 1446 | } |
24710c48 | 1447 | |
96bb7673 | 1448 | int dnssec_verify_dnskey_by_ds_search(DnsResourceRecord *dnskey, DnsAnswer *validated_ds) { |
547973de | 1449 | DnsResourceRecord *ds; |
105e1512 | 1450 | DnsAnswerFlags flags; |
547973de LP |
1451 | int r; |
1452 | ||
1453 | assert(dnskey); | |
1454 | ||
1455 | if (dnskey->key->type != DNS_TYPE_DNSKEY) | |
1456 | return 0; | |
1457 | ||
105e1512 LP |
1458 | DNS_ANSWER_FOREACH_FLAGS(ds, flags, validated_ds) { |
1459 | ||
1460 | if ((flags & DNS_ANSWER_AUTHENTICATED) == 0) | |
1461 | continue; | |
547973de LP |
1462 | |
1463 | if (ds->key->type != DNS_TYPE_DS) | |
1464 | continue; | |
d1c4ee32 LP |
1465 | if (ds->key->class != dnskey->key->class) |
1466 | continue; | |
1467 | ||
1c02e7ba | 1468 | r = dns_name_equal(dns_resource_key_name(dnskey->key), dns_resource_key_name(ds->key)); |
d1c4ee32 LP |
1469 | if (r < 0) |
1470 | return r; | |
1471 | if (r == 0) | |
1472 | continue; | |
1473 | ||
96bb7673 | 1474 | r = dnssec_verify_dnskey_by_ds(dnskey, ds, false); |
54b778e7 LP |
1475 | if (IN_SET(r, -EKEYREJECTED, -EOPNOTSUPP)) |
1476 | return 0; /* The DNSKEY is revoked or otherwise invalid, or we don't support the digest algorithm */ | |
547973de LP |
1477 | if (r < 0) |
1478 | return r; | |
1479 | if (r > 0) | |
1480 | return 1; | |
1481 | } | |
1482 | ||
1483 | return 0; | |
1484 | } | |
1485 | ||
1736344e | 1486 | static hash_md_t nsec3_hash_to_hash_md(uint8_t algorithm) { |
d15ad742 | 1487 | |
1736344e | 1488 | /* Translates a DNSSEC NSEC3 hash algorithm into an openssl/gcrypt digest identifier */ |
d15ad742 LP |
1489 | |
1490 | switch (algorithm) { | |
1491 | ||
1492 | case NSEC3_ALGORITHM_SHA1: | |
1736344e | 1493 | return OPENSSL_OR_GCRYPT(EVP_sha1(), GCRY_MD_SHA1); |
d15ad742 LP |
1494 | |
1495 | default: | |
1736344e | 1496 | return OPENSSL_OR_GCRYPT(NULL, -EOPNOTSUPP); |
d15ad742 LP |
1497 | } |
1498 | } | |
1499 | ||
1d3db294 | 1500 | int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) { |
5e55cde9 | 1501 | uint8_t wire_format[DNS_WIRE_FORMAT_HOSTNAME_MAX]; |
72667f08 LP |
1502 | int r; |
1503 | ||
1504 | assert(nsec3); | |
1505 | assert(name); | |
1506 | assert(ret); | |
1507 | ||
1508 | if (nsec3->key->type != DNS_TYPE_NSEC3) | |
1509 | return -EINVAL; | |
1510 | ||
baaa35ad ZJS |
1511 | if (nsec3->nsec3.iterations > NSEC3_ITERATIONS_MAX) |
1512 | return log_debug_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), | |
1513 | "Ignoring NSEC3 RR %s with excessive number of iterations.", | |
1514 | dns_resource_record_to_string(nsec3)); | |
a8f158b9 | 1515 | |
1736344e KK |
1516 | hash_md_t algorithm = nsec3_hash_to_hash_md(nsec3->nsec3.algorithm); |
1517 | #if PREFER_OPENSSL | |
1518 | if (!algorithm) | |
1519 | return -EOPNOTSUPP; | |
1520 | ||
1521 | size_t hash_size = EVP_MD_size(algorithm); | |
1522 | assert(hash_size > 0); | |
1523 | ||
1524 | if (nsec3->nsec3.next_hashed_name_size != hash_size) | |
1525 | return -EINVAL; | |
1526 | ||
1527 | _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = EVP_MD_CTX_new(); | |
1528 | if (!ctx) | |
1529 | return -ENOMEM; | |
1530 | ||
1531 | if (EVP_DigestInit_ex(ctx, algorithm, NULL) <= 0) | |
1532 | return -EIO; | |
1533 | ||
1534 | r = dns_name_to_wire_format(name, wire_format, sizeof(wire_format), true); | |
1535 | if (r < 0) | |
1536 | return r; | |
1537 | ||
1538 | if (EVP_DigestUpdate(ctx, wire_format, r) <= 0) | |
1539 | return -EIO; | |
1540 | if (EVP_DigestUpdate(ctx, nsec3->nsec3.salt, nsec3->nsec3.salt_size) <= 0) | |
1541 | return -EIO; | |
1542 | ||
1543 | uint8_t result[EVP_MAX_MD_SIZE]; | |
1544 | if (EVP_DigestFinal_ex(ctx, result, NULL) <= 0) | |
1545 | return -EIO; | |
1546 | ||
1547 | for (unsigned k = 0; k < nsec3->nsec3.iterations; k++) { | |
1548 | if (EVP_DigestInit_ex(ctx, algorithm, NULL) <= 0) | |
1549 | return -EIO; | |
1550 | if (EVP_DigestUpdate(ctx, result, hash_size) <= 0) | |
1551 | return -EIO; | |
1552 | if (EVP_DigestUpdate(ctx, nsec3->nsec3.salt, nsec3->nsec3.salt_size) <= 0) | |
1553 | return -EIO; | |
1554 | ||
1555 | if (EVP_DigestFinal_ex(ctx, result, NULL) <= 0) | |
1556 | return -EIO; | |
1557 | } | |
1558 | #else | |
72667f08 LP |
1559 | if (algorithm < 0) |
1560 | return algorithm; | |
1561 | ||
8707c9b2 LB |
1562 | r = initialize_libgcrypt(false); |
1563 | if (r < 0) | |
1564 | return r; | |
72667f08 | 1565 | |
72270f29 | 1566 | size_t encoded_length; |
1736344e | 1567 | unsigned hash_size = gcry_md_get_algo_dlen(algorithm); |
72667f08 LP |
1568 | assert(hash_size > 0); |
1569 | ||
1570 | if (nsec3->nsec3.next_hashed_name_size != hash_size) | |
1571 | return -EINVAL; | |
1572 | ||
1573 | r = dns_name_to_wire_format(name, wire_format, sizeof(wire_format), true); | |
1574 | if (r < 0) | |
1575 | return r; | |
72270f29 | 1576 | encoded_length = r; |
72667f08 | 1577 | |
1736344e KK |
1578 | _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL; |
1579 | gcry_error_t err = gcry_md_open(&md, algorithm, 0); | |
248b1e0a | 1580 | if (gcry_err_code(err) != GPG_ERR_NO_ERROR || !md) |
72667f08 LP |
1581 | return -EIO; |
1582 | ||
72270f29 | 1583 | gcry_md_write(md, wire_format, encoded_length); |
72667f08 LP |
1584 | gcry_md_write(md, nsec3->nsec3.salt, nsec3->nsec3.salt_size); |
1585 | ||
1736344e | 1586 | void *result = gcry_md_read(md, 0); |
677ba9d0 LB |
1587 | if (!result) |
1588 | return -EIO; | |
72667f08 | 1589 | |
6f1d18ae | 1590 | for (unsigned k = 0; k < nsec3->nsec3.iterations; k++) { |
72667f08 LP |
1591 | uint8_t tmp[hash_size]; |
1592 | memcpy(tmp, result, hash_size); | |
1593 | ||
1594 | gcry_md_reset(md); | |
1595 | gcry_md_write(md, tmp, hash_size); | |
1596 | gcry_md_write(md, nsec3->nsec3.salt, nsec3->nsec3.salt_size); | |
1597 | ||
1598 | result = gcry_md_read(md, 0); | |
677ba9d0 LB |
1599 | if (!result) |
1600 | return -EIO; | |
72667f08 | 1601 | } |
1736344e | 1602 | #endif |
72667f08 LP |
1603 | |
1604 | memcpy(ret, result, hash_size); | |
677ba9d0 | 1605 | return (int) hash_size; |
72667f08 LP |
1606 | } |
1607 | ||
3f5ecaad | 1608 | static int nsec3_is_good(DnsResourceRecord *rr, DnsResourceRecord *nsec3) { |
db5b0e92 LP |
1609 | const char *a, *b; |
1610 | int r; | |
1611 | ||
1612 | assert(rr); | |
1613 | ||
db5b0e92 LP |
1614 | if (rr->key->type != DNS_TYPE_NSEC3) |
1615 | return 0; | |
1616 | ||
1f133e0d | 1617 | /* RFC 5155, Section 8.2 says we MUST ignore NSEC3 RRs with flags != 0 or 1 */ |
db5b0e92 LP |
1618 | if (!IN_SET(rr->nsec3.flags, 0, 1)) |
1619 | return 0; | |
1620 | ||
d15ad742 | 1621 | /* Ignore NSEC3 RRs whose algorithm we don't know */ |
1736344e KK |
1622 | #if PREFER_OPENSSL |
1623 | if (!nsec3_hash_to_hash_md(rr->nsec3.algorithm)) | |
1624 | return 0; | |
1625 | #else | |
1626 | if (nsec3_hash_to_hash_md(rr->nsec3.algorithm) < 0) | |
d15ad742 | 1627 | return 0; |
1736344e KK |
1628 | #endif |
1629 | ||
a8f158b9 LP |
1630 | /* Ignore NSEC3 RRs with an excessive number of required iterations */ |
1631 | if (rr->nsec3.iterations > NSEC3_ITERATIONS_MAX) | |
1632 | return 0; | |
d15ad742 | 1633 | |
cbd100ac LP |
1634 | /* Ignore NSEC3 RRs generated from wildcards. If these NSEC3 RRs weren't correctly signed we can't make this |
1635 | * check (since rr->n_skip_labels_source is -1), but that's OK, as we won't trust them anyway in that case. */ | |
98e80bf9 | 1636 | if (!IN_SET(rr->n_skip_labels_source, 0, UINT8_MAX)) |
93a3b929 LP |
1637 | return 0; |
1638 | /* Ignore NSEC3 RRs that are located anywhere else than one label below the zone */ | |
98e80bf9 | 1639 | if (!IN_SET(rr->n_skip_labels_signer, 1, UINT8_MAX)) |
93a3b929 LP |
1640 | return 0; |
1641 | ||
db5b0e92 LP |
1642 | if (!nsec3) |
1643 | return 1; | |
1644 | ||
1645 | /* If a second NSEC3 RR is specified, also check if they are from the same zone. */ | |
1646 | ||
1647 | if (nsec3 == rr) /* Shortcut */ | |
1648 | return 1; | |
1649 | ||
1650 | if (rr->key->class != nsec3->key->class) | |
1651 | return 0; | |
1652 | if (rr->nsec3.algorithm != nsec3->nsec3.algorithm) | |
1653 | return 0; | |
1654 | if (rr->nsec3.iterations != nsec3->nsec3.iterations) | |
1655 | return 0; | |
1656 | if (rr->nsec3.salt_size != nsec3->nsec3.salt_size) | |
1657 | return 0; | |
1f66559c | 1658 | if (memcmp_safe(rr->nsec3.salt, nsec3->nsec3.salt, rr->nsec3.salt_size) != 0) |
db5b0e92 LP |
1659 | return 0; |
1660 | ||
1c02e7ba | 1661 | a = dns_resource_key_name(rr->key); |
db5b0e92 | 1662 | r = dns_name_parent(&a); /* strip off hash */ |
f20db199 | 1663 | if (r <= 0) |
db5b0e92 | 1664 | return r; |
db5b0e92 | 1665 | |
1c02e7ba | 1666 | b = dns_resource_key_name(nsec3->key); |
db5b0e92 | 1667 | r = dns_name_parent(&b); /* strip off hash */ |
f20db199 | 1668 | if (r <= 0) |
db5b0e92 | 1669 | return r; |
db5b0e92 | 1670 | |
93a3b929 | 1671 | /* Make sure both have the same parent */ |
db5b0e92 LP |
1672 | return dns_name_equal(a, b); |
1673 | } | |
1674 | ||
cdbffec0 LP |
1675 | static int nsec3_hashed_domain_format(const uint8_t *hashed, size_t hashed_size, const char *zone, char **ret) { |
1676 | _cleanup_free_ char *l = NULL; | |
1677 | char *j; | |
1678 | ||
1679 | assert(hashed); | |
1680 | assert(hashed_size > 0); | |
1681 | assert(zone); | |
1682 | assert(ret); | |
1683 | ||
1684 | l = base32hexmem(hashed, hashed_size, false); | |
1685 | if (!l) | |
1686 | return -ENOMEM; | |
1687 | ||
605405c6 | 1688 | j = strjoin(l, ".", zone); |
cdbffec0 LP |
1689 | if (!j) |
1690 | return -ENOMEM; | |
1691 | ||
1692 | *ret = j; | |
1693 | return (int) hashed_size; | |
1694 | } | |
1695 | ||
1696 | static int nsec3_hashed_domain_make(DnsResourceRecord *nsec3, const char *domain, const char *zone, char **ret) { | |
105e1512 | 1697 | uint8_t hashed[DNSSEC_HASH_SIZE_MAX]; |
6f76ec5a TG |
1698 | int hashed_size; |
1699 | ||
1700 | assert(nsec3); | |
1701 | assert(domain); | |
1702 | assert(zone); | |
1703 | assert(ret); | |
1704 | ||
1705 | hashed_size = dnssec_nsec3_hash(nsec3, domain, hashed); | |
1706 | if (hashed_size < 0) | |
1707 | return hashed_size; | |
1708 | ||
cdbffec0 | 1709 | return nsec3_hashed_domain_format(hashed, (size_t) hashed_size, zone, ret); |
6f76ec5a TG |
1710 | } |
1711 | ||
35ad41d3 TG |
1712 | /* See RFC 5155, Section 8 |
1713 | * First try to find a NSEC3 record that matches our query precisely, if that fails, find the closest | |
1714 | * enclosure. Secondly, find a proof that there is no closer enclosure and either a proof that there | |
1715 | * is no wildcard domain as a direct descendant of the closest enclosure, or find an NSEC3 record that | |
1716 | * matches the wildcard domain. | |
1717 | * | |
1718 | * Based on this we can prove either the existence of the record in @key, or NXDOMAIN or NODATA, or | |
d51c4fca | 1719 | * that there is no proof either way. The latter is the case if a proof of non-existence of a given |
35ad41d3 TG |
1720 | * name uses an NSEC3 record with the opt-out bit set. Lastly, if we are given insufficient NSEC3 records |
1721 | * to conclude anything we indicate this by returning NO_RR. */ | |
d3760be0 | 1722 | static int dnssec_test_nsec3(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) { |
d41084a5 LP |
1723 | _cleanup_free_ char *next_closer_domain = NULL, *wildcard_domain = NULL; |
1724 | const char *zone, *p, *pp = NULL, *wildcard; | |
7e35195f | 1725 | DnsResourceRecord *rr, *enclosure_rr, *zone_rr, *wildcard_rr = NULL; |
105e1512 LP |
1726 | DnsAnswerFlags flags; |
1727 | int hashed_size, r; | |
35ad41d3 | 1728 | bool a, no_closer = false, no_wildcard = false, optout = false; |
72667f08 LP |
1729 | |
1730 | assert(key); | |
1731 | assert(result); | |
1732 | ||
d1511b33 TG |
1733 | /* First step, find the zone name and the NSEC3 parameters of the zone. |
1734 | * it is sufficient to look for the longest common suffix we find with | |
1735 | * any NSEC3 RR in the response. Any NSEC3 record will do as all NSEC3 | |
1736 | * records from a given zone in a response must use the same | |
1737 | * parameters. */ | |
1c02e7ba | 1738 | zone = dns_resource_key_name(key); |
13b78323 | 1739 | for (;;) { |
7e35195f | 1740 | DNS_ANSWER_FOREACH_FLAGS(zone_rr, flags, answer) { |
3f5ecaad | 1741 | r = nsec3_is_good(zone_rr, NULL); |
db5b0e92 LP |
1742 | if (r < 0) |
1743 | return r; | |
1744 | if (r == 0) | |
13b78323 LP |
1745 | continue; |
1746 | ||
1c02e7ba | 1747 | r = dns_name_equal_skip(dns_resource_key_name(zone_rr->key), 1, zone); |
13b78323 LP |
1748 | if (r < 0) |
1749 | return r; | |
1750 | if (r > 0) | |
d1511b33 | 1751 | goto found_zone; |
13b78323 LP |
1752 | } |
1753 | ||
1754 | /* Strip one label from the front */ | |
d1511b33 | 1755 | r = dns_name_parent(&zone); |
13b78323 LP |
1756 | if (r < 0) |
1757 | return r; | |
1758 | if (r == 0) | |
1759 | break; | |
1760 | } | |
1761 | ||
1762 | *result = DNSSEC_NSEC_NO_RR; | |
1763 | return 0; | |
1764 | ||
d1511b33 | 1765 | found_zone: |
13b78323 | 1766 | /* Second step, find the closest encloser NSEC3 RR in 'answer' that matches 'key' */ |
1c02e7ba | 1767 | p = dns_resource_key_name(key); |
105e1512 | 1768 | for (;;) { |
6f76ec5a | 1769 | _cleanup_free_ char *hashed_domain = NULL; |
72667f08 | 1770 | |
cdbffec0 | 1771 | hashed_size = nsec3_hashed_domain_make(zone_rr, p, zone, &hashed_domain); |
db5b0e92 LP |
1772 | if (hashed_size == -EOPNOTSUPP) { |
1773 | *result = DNSSEC_NSEC_UNSUPPORTED_ALGORITHM; | |
1774 | return 0; | |
1775 | } | |
1776 | if (hashed_size < 0) | |
1777 | return hashed_size; | |
72667f08 | 1778 | |
d1511b33 | 1779 | DNS_ANSWER_FOREACH_FLAGS(enclosure_rr, flags, answer) { |
db5b0e92 | 1780 | |
3f5ecaad | 1781 | r = nsec3_is_good(enclosure_rr, zone_rr); |
72667f08 LP |
1782 | if (r < 0) |
1783 | return r; | |
105e1512 LP |
1784 | if (r == 0) |
1785 | continue; | |
1786 | ||
d1511b33 | 1787 | if (enclosure_rr->nsec3.next_hashed_name_size != (size_t) hashed_size) |
db5b0e92 | 1788 | continue; |
105e1512 | 1789 | |
1c02e7ba | 1790 | r = dns_name_equal(dns_resource_key_name(enclosure_rr->key), hashed_domain); |
72667f08 LP |
1791 | if (r < 0) |
1792 | return r; | |
ed29bfdc LP |
1793 | if (r > 0) { |
1794 | a = flags & DNS_ANSWER_AUTHENTICATED; | |
13b78323 | 1795 | goto found_closest_encloser; |
ed29bfdc | 1796 | } |
105e1512 LP |
1797 | } |
1798 | ||
1799 | /* We didn't find the closest encloser with this name, | |
1800 | * but let's remember this domain name, it might be | |
1801 | * the next closer name */ | |
1802 | ||
1803 | pp = p; | |
1804 | ||
1805 | /* Strip one label from the front */ | |
1806 | r = dns_name_parent(&p); | |
1807 | if (r < 0) | |
1808 | return r; | |
1809 | if (r == 0) | |
72667f08 | 1810 | break; |
105e1512 | 1811 | } |
72667f08 | 1812 | |
105e1512 LP |
1813 | *result = DNSSEC_NSEC_NO_RR; |
1814 | return 0; | |
72667f08 | 1815 | |
13b78323 | 1816 | found_closest_encloser: |
105e1512 | 1817 | /* We found a closest encloser in 'p'; next closer is 'pp' */ |
72667f08 | 1818 | |
105e1512 | 1819 | if (!pp) { |
352af308 LP |
1820 | /* We have an exact match! If we area looking for a DS RR, then we must insist that we got the NSEC3 RR |
1821 | * from the parent. Otherwise the one from the child. Do so, by checking whether SOA and NS are | |
1822 | * appropriately set. */ | |
1823 | ||
1824 | if (key->type == DNS_TYPE_DS) { | |
1825 | if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_SOA)) | |
1826 | return -EBADMSG; | |
1827 | } else { | |
1828 | if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_NS) && | |
1829 | !bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_SOA)) | |
1830 | return -EBADMSG; | |
1831 | } | |
1832 | ||
105e1512 | 1833 | /* No next closer NSEC3 RR. That means there's a direct NSEC3 RR for our key. */ |
146035b3 TG |
1834 | if (bitmap_isset(enclosure_rr->nsec3.types, key->type)) |
1835 | *result = DNSSEC_NSEC_FOUND; | |
1836 | else if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_CNAME)) | |
1837 | *result = DNSSEC_NSEC_CNAME; | |
1838 | else | |
1839 | *result = DNSSEC_NSEC_NODATA; | |
1840 | ||
d3760be0 LP |
1841 | if (authenticated) |
1842 | *authenticated = a; | |
1843 | if (ttl) | |
1844 | *ttl = enclosure_rr->ttl; | |
146035b3 | 1845 | |
105e1512 LP |
1846 | return 0; |
1847 | } | |
72667f08 | 1848 | |
352af308 LP |
1849 | /* Ensure this is not a DNAME domain, see RFC5155, section 8.3. */ |
1850 | if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_DNAME)) | |
1851 | return -EBADMSG; | |
1852 | ||
1853 | /* Ensure that this data is from the delegated domain | |
1854 | * (i.e. originates from the "lower" DNS server), and isn't | |
1855 | * just glue records (i.e. doesn't originate from the "upper" | |
1856 | * DNS server). */ | |
1857 | if (bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_NS) && | |
1858 | !bitmap_isset(enclosure_rr->nsec3.types, DNS_TYPE_SOA)) | |
1859 | return -EBADMSG; | |
1860 | ||
35ad41d3 TG |
1861 | /* Prove that there is no next closer and whether or not there is a wildcard domain. */ |
1862 | ||
d41084a5 | 1863 | wildcard = strjoina("*.", p); |
cdbffec0 | 1864 | r = nsec3_hashed_domain_make(enclosure_rr, wildcard, zone, &wildcard_domain); |
105e1512 LP |
1865 | if (r < 0) |
1866 | return r; | |
1867 | if (r != hashed_size) | |
1868 | return -EBADMSG; | |
72667f08 | 1869 | |
cdbffec0 | 1870 | r = nsec3_hashed_domain_make(enclosure_rr, pp, zone, &next_closer_domain); |
105e1512 LP |
1871 | if (r < 0) |
1872 | return r; | |
1873 | if (r != hashed_size) | |
1874 | return -EBADMSG; | |
72667f08 | 1875 | |
105e1512 | 1876 | DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) { |
cdbffec0 | 1877 | _cleanup_free_ char *next_hashed_domain = NULL; |
105e1512 | 1878 | |
3f5ecaad | 1879 | r = nsec3_is_good(rr, zone_rr); |
105e1512 LP |
1880 | if (r < 0) |
1881 | return r; | |
1882 | if (r == 0) | |
1883 | continue; | |
1884 | ||
cdbffec0 LP |
1885 | r = nsec3_hashed_domain_format(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size, zone, &next_hashed_domain); |
1886 | if (r < 0) | |
1887 | return r; | |
105e1512 | 1888 | |
1c02e7ba | 1889 | r = dns_name_between(dns_resource_key_name(rr->key), next_closer_domain, next_hashed_domain); |
105e1512 LP |
1890 | if (r < 0) |
1891 | return r; | |
1892 | if (r > 0) { | |
1893 | if (rr->nsec3.flags & 1) | |
35ad41d3 | 1894 | optout = true; |
105e1512 | 1895 | |
35ad41d3 TG |
1896 | a = a && (flags & DNS_ANSWER_AUTHENTICATED); |
1897 | ||
1898 | no_closer = true; | |
1899 | } | |
1900 | ||
1c02e7ba | 1901 | r = dns_name_equal(dns_resource_key_name(rr->key), wildcard_domain); |
35ad41d3 TG |
1902 | if (r < 0) |
1903 | return r; | |
1904 | if (r > 0) { | |
1905 | a = a && (flags & DNS_ANSWER_AUTHENTICATED); | |
1906 | ||
1907 | wildcard_rr = rr; | |
1908 | } | |
1909 | ||
1c02e7ba | 1910 | r = dns_name_between(dns_resource_key_name(rr->key), wildcard_domain, next_hashed_domain); |
35ad41d3 TG |
1911 | if (r < 0) |
1912 | return r; | |
1913 | if (r > 0) { | |
1914 | if (rr->nsec3.flags & 1) | |
1915 | /* This only makes sense if we have a wildcard delegation, which is | |
1916 | * very unlikely, see RFC 4592, Section 4.2, but we cannot rely on | |
1917 | * this not happening, so hence cannot simply conclude NXDOMAIN as | |
1918 | * we would wish */ | |
1919 | optout = true; | |
1920 | ||
1921 | a = a && (flags & DNS_ANSWER_AUTHENTICATED); | |
1922 | ||
1923 | no_wildcard = true; | |
105e1512 LP |
1924 | } |
1925 | } | |
1926 | ||
35ad41d3 TG |
1927 | if (wildcard_rr && no_wildcard) |
1928 | return -EBADMSG; | |
1929 | ||
1930 | if (!no_closer) { | |
1931 | *result = DNSSEC_NSEC_NO_RR; | |
35ad41d3 TG |
1932 | return 0; |
1933 | } | |
1934 | ||
1935 | if (wildcard_rr) { | |
1936 | /* A wildcard exists that matches our query. */ | |
1937 | if (optout) | |
1938 | /* This is not specified in any RFC to the best of my knowledge, but | |
1939 | * if the next closer enclosure is covered by an opt-out NSEC3 RR | |
1940 | * it means that we cannot prove that the source of synthesis is | |
1941 | * correct, as there may be a closer match. */ | |
1942 | *result = DNSSEC_NSEC_OPTOUT; | |
1943 | else if (bitmap_isset(wildcard_rr->nsec3.types, key->type)) | |
1944 | *result = DNSSEC_NSEC_FOUND; | |
1945 | else if (bitmap_isset(wildcard_rr->nsec3.types, DNS_TYPE_CNAME)) | |
1946 | *result = DNSSEC_NSEC_CNAME; | |
1947 | else | |
1948 | *result = DNSSEC_NSEC_NODATA; | |
1949 | } else { | |
1950 | if (optout) | |
1951 | /* The RFC only specifies that we have to care for optout for NODATA for | |
1952 | * DS records. However, children of an insecure opt-out delegation should | |
1953 | * also be considered opt-out, rather than verified NXDOMAIN. | |
1954 | * Note that we do not require a proof of wildcard non-existence if the | |
1955 | * next closer domain is covered by an opt-out, as that would not provide | |
1956 | * any additional information. */ | |
1957 | *result = DNSSEC_NSEC_OPTOUT; | |
1958 | else if (no_wildcard) | |
1959 | *result = DNSSEC_NSEC_NXDOMAIN; | |
1960 | else { | |
1961 | *result = DNSSEC_NSEC_NO_RR; | |
1962 | ||
1963 | return 0; | |
1964 | } | |
1965 | } | |
1966 | ||
d3760be0 LP |
1967 | if (authenticated) |
1968 | *authenticated = a; | |
1969 | ||
1970 | if (ttl) | |
1971 | *ttl = enclosure_rr->ttl; | |
35ad41d3 | 1972 | |
105e1512 LP |
1973 | return 0; |
1974 | } | |
1975 | ||
ab481675 | 1976 | static int dnssec_nsec_wildcard_equal(DnsResourceRecord *rr, const char *name) { |
fd7e9887 | 1977 | char label[DNS_LABEL_MAX+1]; |
ab481675 LP |
1978 | const char *n; |
1979 | int r; | |
1980 | ||
1981 | assert(rr); | |
1982 | assert(rr->key->type == DNS_TYPE_NSEC); | |
1983 | ||
1984 | /* Checks whether the specified RR has a name beginning in "*.", and if the rest is a suffix of our name */ | |
1985 | ||
1986 | if (rr->n_skip_labels_source != 1) | |
1987 | return 0; | |
1988 | ||
1c02e7ba | 1989 | n = dns_resource_key_name(rr->key); |
7470cc4c | 1990 | r = dns_label_unescape(&n, label, sizeof label, 0); |
ab481675 LP |
1991 | if (r <= 0) |
1992 | return r; | |
1993 | if (r != 1 || label[0] != '*') | |
1994 | return 0; | |
1995 | ||
1996 | return dns_name_endswith(name, n); | |
1997 | } | |
1998 | ||
1999 | static int dnssec_nsec_in_path(DnsResourceRecord *rr, const char *name) { | |
b9282bc1 LP |
2000 | const char *nn, *common_suffix; |
2001 | int r; | |
2002 | ||
2003 | assert(rr); | |
2004 | assert(rr->key->type == DNS_TYPE_NSEC); | |
2005 | ||
2006 | /* Checks whether the specified nsec RR indicates that name is an empty non-terminal (ENT) | |
2007 | * | |
2008 | * A couple of examples: | |
2009 | * | |
2010 | * NSEC bar → waldo.foo.bar: indicates that foo.bar exists and is an ENT | |
2011 | * NSEC waldo.foo.bar → yyy.zzz.xoo.bar: indicates that xoo.bar and zzz.xoo.bar exist and are ENTs | |
2012 | * NSEC yyy.zzz.xoo.bar → bar: indicates pretty much nothing about ENTs | |
2013 | */ | |
2014 | ||
2015 | /* First, determine parent of next domain. */ | |
2016 | nn = rr->nsec.next_domain_name; | |
2017 | r = dns_name_parent(&nn); | |
2018 | if (r <= 0) | |
2019 | return r; | |
2020 | ||
2021 | /* If the name we just determined is not equal or child of the name we are interested in, then we can't say | |
2022 | * anything at all. */ | |
2023 | r = dns_name_endswith(nn, name); | |
2024 | if (r <= 0) | |
2025 | return r; | |
2026 | ||
61233823 | 2027 | /* 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 | 2028 | r = dns_name_common_suffix(dns_resource_key_name(rr->key), rr->nsec.next_domain_name, &common_suffix); |
b9282bc1 LP |
2029 | if (r < 0) |
2030 | return r; | |
2031 | ||
2032 | return dns_name_endswith(name, common_suffix); | |
2033 | } | |
2034 | ||
ab481675 LP |
2035 | static int dnssec_nsec_from_parent_zone(DnsResourceRecord *rr, const char *name) { |
2036 | int r; | |
2037 | ||
2038 | assert(rr); | |
2039 | assert(rr->key->type == DNS_TYPE_NSEC); | |
2040 | ||
2041 | /* Checks whether this NSEC originates to the parent zone or the child zone. */ | |
2042 | ||
2043 | r = dns_name_parent(&name); | |
2044 | if (r <= 0) | |
2045 | return r; | |
2046 | ||
1c02e7ba | 2047 | r = dns_name_equal(name, dns_resource_key_name(rr->key)); |
ab481675 LP |
2048 | if (r <= 0) |
2049 | return r; | |
2050 | ||
2051 | /* DNAME, and NS without SOA is an indication for a delegation. */ | |
2052 | if (bitmap_isset(rr->nsec.types, DNS_TYPE_DNAME)) | |
2053 | return 1; | |
2054 | ||
2055 | if (bitmap_isset(rr->nsec.types, DNS_TYPE_NS) && !bitmap_isset(rr->nsec.types, DNS_TYPE_SOA)) | |
2056 | return 1; | |
2057 | ||
2058 | return 0; | |
2059 | } | |
2060 | ||
2061 | static int dnssec_nsec_covers(DnsResourceRecord *rr, const char *name) { | |
0b491556 | 2062 | const char *signer; |
ab481675 LP |
2063 | int r; |
2064 | ||
2065 | assert(rr); | |
2066 | assert(rr->key->type == DNS_TYPE_NSEC); | |
2067 | ||
0b491556 LP |
2068 | /* Checks whether the name is covered by this NSEC RR. This means, that the name is somewhere below the NSEC's |
2069 | * signer name, and between the NSEC's two names. */ | |
ab481675 | 2070 | |
0b491556 | 2071 | r = dns_resource_record_signer(rr, &signer); |
ab481675 LP |
2072 | if (r < 0) |
2073 | return r; | |
2074 | ||
0b491556 LP |
2075 | r = dns_name_endswith(name, signer); /* this NSEC isn't suitable the name is not in the signer's domain */ |
2076 | if (r <= 0) | |
2077 | return r; | |
ab481675 | 2078 | |
0b491556 | 2079 | return dns_name_between(dns_resource_key_name(rr->key), name, rr->nsec.next_domain_name); |
ab481675 LP |
2080 | } |
2081 | ||
13e6f383 AT |
2082 | static int dnssec_nsec_generate_wildcard(DnsResourceRecord *rr, const char *name, char **wc) { |
2083 | const char *common_suffix1, *common_suffix2, *signer; | |
2084 | int r, labels1, labels2; | |
d86c982a LP |
2085 | |
2086 | assert(rr); | |
2087 | assert(rr->key->type == DNS_TYPE_NSEC); | |
2088 | ||
13e6f383 | 2089 | /* Generates "Wildcard at the Closest Encloser" for the given name and NSEC RR. */ |
d86c982a | 2090 | |
0b491556 | 2091 | r = dns_resource_record_signer(rr, &signer); |
d86c982a LP |
2092 | if (r < 0) |
2093 | return r; | |
2094 | ||
0b491556 | 2095 | r = dns_name_endswith(name, signer); /* this NSEC isn't suitable the name is not in the signer's domain */ |
d86c982a LP |
2096 | if (r <= 0) |
2097 | return r; | |
2098 | ||
13e6f383 | 2099 | r = dns_name_common_suffix(name, dns_resource_key_name(rr->key), &common_suffix1); |
0b491556 LP |
2100 | if (r < 0) |
2101 | return r; | |
0b491556 | 2102 | |
13e6f383 AT |
2103 | r = dns_name_common_suffix(name, rr->nsec.next_domain_name, &common_suffix2); |
2104 | if (r < 0) | |
2105 | return r; | |
2106 | ||
2107 | labels1 = dns_name_count_labels(common_suffix1); | |
2108 | if (labels1 < 0) | |
2109 | return labels1; | |
2110 | ||
2111 | labels2 = dns_name_count_labels(common_suffix2); | |
2112 | if (labels2 < 0) | |
2113 | return labels2; | |
2114 | ||
2115 | if (labels1 > labels2) | |
2116 | r = dns_name_concat("*", common_suffix1, 0, wc); | |
2117 | else | |
2118 | r = dns_name_concat("*", common_suffix2, 0, wc); | |
2119 | ||
97c2ea26 LP |
2120 | if (r < 0) |
2121 | return r; | |
2122 | ||
13e6f383 | 2123 | return 0; |
d86c982a LP |
2124 | } |
2125 | ||
0c7bff0a | 2126 | int dnssec_nsec_test(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) { |
d86c982a LP |
2127 | bool have_nsec3 = false, covering_rr_authenticated = false, wildcard_rr_authenticated = false; |
2128 | DnsResourceRecord *rr, *covering_rr = NULL, *wildcard_rr = NULL; | |
105e1512 | 2129 | DnsAnswerFlags flags; |
b9282bc1 | 2130 | const char *name; |
105e1512 LP |
2131 | int r; |
2132 | ||
2133 | assert(key); | |
2134 | assert(result); | |
2135 | ||
2136 | /* Look for any NSEC/NSEC3 RRs that say something about the specified key. */ | |
2137 | ||
1c02e7ba | 2138 | name = dns_resource_key_name(key); |
b9282bc1 | 2139 | |
105e1512 LP |
2140 | DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) { |
2141 | ||
2142 | if (rr->key->class != key->class) | |
2143 | continue; | |
2144 | ||
ab481675 | 2145 | have_nsec3 = have_nsec3 || (rr->key->type == DNS_TYPE_NSEC3); |
105e1512 | 2146 | |
ab481675 LP |
2147 | if (rr->key->type != DNS_TYPE_NSEC) |
2148 | continue; | |
2149 | ||
2150 | /* The following checks only make sense for NSEC RRs that are not expanded from a wildcard */ | |
2151 | r = dns_resource_record_is_synthetic(rr); | |
2f4c2db2 LP |
2152 | if (r == -ENODATA) /* No signing RR known. */ |
2153 | continue; | |
ab481675 LP |
2154 | if (r < 0) |
2155 | return r; | |
2156 | if (r > 0) | |
2157 | continue; | |
105e1512 | 2158 | |
ab481675 | 2159 | /* Check if this is a direct match. If so, we have encountered a NODATA case */ |
1c02e7ba | 2160 | r = dns_name_equal(dns_resource_key_name(rr->key), name); |
ab481675 LP |
2161 | if (r < 0) |
2162 | return r; | |
2163 | if (r == 0) { | |
2164 | /* If it's not a direct match, maybe it's a wild card match? */ | |
2165 | r = dnssec_nsec_wildcard_equal(rr, name); | |
105e1512 LP |
2166 | if (r < 0) |
2167 | return r; | |
ab481675 LP |
2168 | } |
2169 | if (r > 0) { | |
2170 | if (key->type == DNS_TYPE_DS) { | |
2171 | /* If we look for a DS RR and the server sent us the NSEC RR of the child zone | |
2172 | * we have a problem. For DS RRs we want the NSEC RR from the parent */ | |
2173 | if (bitmap_isset(rr->nsec.types, DNS_TYPE_SOA)) | |
2174 | continue; | |
2175 | } else { | |
2176 | /* For all RR types, ensure that if NS is set SOA is set too, so that we know | |
2177 | * we got the child's NSEC. */ | |
2178 | if (bitmap_isset(rr->nsec.types, DNS_TYPE_NS) && | |
2179 | !bitmap_isset(rr->nsec.types, DNS_TYPE_SOA)) | |
2180 | continue; | |
72667f08 LP |
2181 | } |
2182 | ||
ab481675 LP |
2183 | if (bitmap_isset(rr->nsec.types, key->type)) |
2184 | *result = DNSSEC_NSEC_FOUND; | |
2185 | else if (bitmap_isset(rr->nsec.types, DNS_TYPE_CNAME)) | |
2186 | *result = DNSSEC_NSEC_CNAME; | |
2187 | else | |
b9282bc1 | 2188 | *result = DNSSEC_NSEC_NODATA; |
d3760be0 | 2189 | |
ab481675 LP |
2190 | if (authenticated) |
2191 | *authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
2192 | if (ttl) | |
2193 | *ttl = rr->ttl; | |
d3760be0 | 2194 | |
ab481675 LP |
2195 | return 0; |
2196 | } | |
b9282bc1 | 2197 | |
ab481675 LP |
2198 | /* Check if the name we are looking for is an empty non-terminal within the owner or next name |
2199 | * of the NSEC RR. */ | |
2200 | r = dnssec_nsec_in_path(rr, name); | |
2201 | if (r < 0) | |
2202 | return r; | |
2203 | if (r > 0) { | |
2204 | *result = DNSSEC_NSEC_NODATA; | |
b9282bc1 | 2205 | |
ab481675 LP |
2206 | if (authenticated) |
2207 | *authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
2208 | if (ttl) | |
2209 | *ttl = rr->ttl; | |
b9282bc1 | 2210 | |
ab481675 LP |
2211 | return 0; |
2212 | } | |
72667f08 | 2213 | |
ab481675 LP |
2214 | /* The following two "covering" checks, are not useful if the NSEC is from the parent */ |
2215 | r = dnssec_nsec_from_parent_zone(rr, name); | |
2216 | if (r < 0) | |
2217 | return r; | |
2218 | if (r > 0) | |
2219 | continue; | |
2220 | ||
2221 | /* Check if this NSEC RR proves the absence of an explicit RR under this name */ | |
2222 | r = dnssec_nsec_covers(rr, name); | |
2223 | if (r < 0) | |
2224 | return r; | |
2225 | if (r > 0 && (!covering_rr || !covering_rr_authenticated)) { | |
2226 | covering_rr = rr; | |
2227 | covering_rr_authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
2228 | } | |
13e6f383 | 2229 | } |
ab481675 | 2230 | |
13e6f383 AT |
2231 | if (covering_rr) { |
2232 | _cleanup_free_ char *wc = NULL; | |
2233 | r = dnssec_nsec_generate_wildcard(covering_rr, name, &wc); | |
ab481675 LP |
2234 | if (r < 0) |
2235 | return r; | |
13e6f383 AT |
2236 | |
2237 | DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) { | |
2238 | ||
2239 | if (rr->key->class != key->class) | |
2240 | continue; | |
2241 | ||
2242 | if (rr->key->type != DNS_TYPE_NSEC) | |
2243 | continue; | |
2244 | ||
2245 | /* Check if this NSEC RR proves the nonexistence of the wildcard */ | |
2246 | r = dnssec_nsec_covers(rr, wc); | |
2247 | if (r < 0) | |
2248 | return r; | |
2249 | if (r > 0 && (!wildcard_rr || !wildcard_rr_authenticated)) { | |
2250 | wildcard_rr = rr; | |
2251 | wildcard_rr_authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
2252 | } | |
72667f08 LP |
2253 | } |
2254 | } | |
2255 | ||
d86c982a LP |
2256 | if (covering_rr && wildcard_rr) { |
2257 | /* If we could prove that neither the name itself, nor the wildcard at the closest encloser exists, we | |
2258 | * proved the NXDOMAIN case. */ | |
2259 | *result = DNSSEC_NSEC_NXDOMAIN; | |
2260 | ||
2261 | if (authenticated) | |
2262 | *authenticated = covering_rr_authenticated && wildcard_rr_authenticated; | |
2263 | if (ttl) | |
2264 | *ttl = MIN(covering_rr->ttl, wildcard_rr->ttl); | |
2265 | ||
2266 | return 0; | |
2267 | } | |
2268 | ||
105e1512 LP |
2269 | /* OK, this was not sufficient. Let's see if NSEC3 can help. */ |
2270 | if (have_nsec3) | |
d3760be0 | 2271 | return dnssec_test_nsec3(answer, key, result, authenticated, ttl); |
105e1512 | 2272 | |
5238e957 | 2273 | /* No appropriate NSEC RR found, report this. */ |
72667f08 LP |
2274 | *result = DNSSEC_NSEC_NO_RR; |
2275 | return 0; | |
2276 | } | |
2277 | ||
421cc89d | 2278 | static int dnssec_nsec_test_enclosed(DnsAnswer *answer, uint16_t type, const char *name, const char *zone, bool *authenticated) { |
0c7bff0a LP |
2279 | DnsResourceRecord *rr; |
2280 | DnsAnswerFlags flags; | |
2281 | int r; | |
2282 | ||
2283 | assert(name); | |
2284 | assert(zone); | |
2285 | ||
2286 | /* Checks whether there's an NSEC/NSEC3 that proves that the specified 'name' is non-existing in the specified | |
2287 | * 'zone'. The 'zone' must be a suffix of the 'name'. */ | |
2288 | ||
2289 | DNS_ANSWER_FOREACH_FLAGS(rr, flags, answer) { | |
2290 | bool found = false; | |
2291 | ||
e926785a LP |
2292 | if (rr->key->type != type && type != DNS_TYPE_ANY) |
2293 | continue; | |
2294 | ||
0c7bff0a LP |
2295 | switch (rr->key->type) { |
2296 | ||
2297 | case DNS_TYPE_NSEC: | |
97c67192 LP |
2298 | |
2299 | /* We only care for NSEC RRs from the indicated zone */ | |
2300 | r = dns_resource_record_is_signer(rr, zone); | |
2301 | if (r < 0) | |
2302 | return r; | |
2303 | if (r == 0) | |
2304 | continue; | |
2305 | ||
1c02e7ba | 2306 | r = dns_name_between(dns_resource_key_name(rr->key), name, rr->nsec.next_domain_name); |
0c7bff0a LP |
2307 | if (r < 0) |
2308 | return r; | |
2309 | ||
2310 | found = r > 0; | |
2311 | break; | |
2312 | ||
2313 | case DNS_TYPE_NSEC3: { | |
2314 | _cleanup_free_ char *hashed_domain = NULL, *next_hashed_domain = NULL; | |
2315 | ||
97c67192 LP |
2316 | /* We only care for NSEC3 RRs from the indicated zone */ |
2317 | r = dns_resource_record_is_signer(rr, zone); | |
2318 | if (r < 0) | |
2319 | return r; | |
2320 | if (r == 0) | |
2321 | continue; | |
2322 | ||
0c7bff0a LP |
2323 | r = nsec3_is_good(rr, NULL); |
2324 | if (r < 0) | |
2325 | return r; | |
2326 | if (r == 0) | |
2327 | break; | |
2328 | ||
2329 | /* Format the domain we are testing with the NSEC3 RR's hash function */ | |
2330 | r = nsec3_hashed_domain_make( | |
2331 | rr, | |
2332 | name, | |
2333 | zone, | |
2334 | &hashed_domain); | |
2335 | if (r < 0) | |
2336 | return r; | |
2337 | if ((size_t) r != rr->nsec3.next_hashed_name_size) | |
2338 | break; | |
2339 | ||
2340 | /* Format the NSEC3's next hashed name as proper domain name */ | |
2341 | r = nsec3_hashed_domain_format( | |
2342 | rr->nsec3.next_hashed_name, | |
2343 | rr->nsec3.next_hashed_name_size, | |
2344 | zone, | |
2345 | &next_hashed_domain); | |
2346 | if (r < 0) | |
2347 | return r; | |
2348 | ||
1c02e7ba | 2349 | r = dns_name_between(dns_resource_key_name(rr->key), hashed_domain, next_hashed_domain); |
0c7bff0a LP |
2350 | if (r < 0) |
2351 | return r; | |
2352 | ||
2353 | found = r > 0; | |
2354 | break; | |
2355 | } | |
2356 | ||
2357 | default: | |
2358 | continue; | |
2359 | } | |
2360 | ||
2361 | if (found) { | |
2362 | if (authenticated) | |
2363 | *authenticated = flags & DNS_ANSWER_AUTHENTICATED; | |
2364 | return 1; | |
2365 | } | |
2366 | } | |
2367 | ||
2368 | return 0; | |
2369 | } | |
2370 | ||
e926785a LP |
2371 | static int dnssec_test_positive_wildcard_nsec3( |
2372 | DnsAnswer *answer, | |
2373 | const char *name, | |
2374 | const char *source, | |
2375 | const char *zone, | |
2376 | bool *authenticated) { | |
2377 | ||
2378 | const char *next_closer = NULL; | |
2379 | int r; | |
2380 | ||
2381 | /* Run a positive NSEC3 wildcard proof. Specifically: | |
2382 | * | |
c629ff58 | 2383 | * A proof that the "next closer" of the generating wildcard does not exist. |
e926785a LP |
2384 | * |
2385 | * Note a key difference between the NSEC3 and NSEC versions of the proof. NSEC RRs don't have to exist for | |
2386 | * empty non-transients. NSEC3 RRs however have to. This means it's sufficient to check if the next closer name | |
2387 | * exists for the NSEC3 RR and we are done. | |
2388 | * | |
2389 | * 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 | |
2390 | * c.d.e.f does not exist. */ | |
2391 | ||
2392 | for (;;) { | |
2393 | next_closer = name; | |
2394 | r = dns_name_parent(&name); | |
f20db199 | 2395 | if (r <= 0) |
e926785a | 2396 | return r; |
e926785a LP |
2397 | |
2398 | r = dns_name_equal(name, source); | |
2399 | if (r < 0) | |
2400 | return r; | |
2401 | if (r > 0) | |
2402 | break; | |
2403 | } | |
2404 | ||
2405 | return dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC3, next_closer, zone, authenticated); | |
2406 | } | |
2407 | ||
2408 | static int dnssec_test_positive_wildcard_nsec( | |
2409 | DnsAnswer *answer, | |
2410 | const char *name, | |
2411 | const char *source, | |
2412 | const char *zone, | |
2413 | bool *_authenticated) { | |
2414 | ||
2415 | bool authenticated = true; | |
2416 | int r; | |
2417 | ||
2418 | /* Run a positive NSEC wildcard proof. Specifically: | |
2419 | * | |
2420 | * A proof that there's neither a wildcard name nor a non-wildcard name that is a suffix of the name "name" and | |
2421 | * a prefix of the synthesizing source "source" in the zone "zone". | |
2422 | * | |
2423 | * See RFC 5155, Section 8.8 and RFC 4035, Section 5.3.4 | |
2424 | * | |
2425 | * 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 | |
2426 | * have to prove that none of the following exist: | |
2427 | * | |
2428 | * 1) a.b.c.d.e.f | |
2429 | * 2) *.b.c.d.e.f | |
2430 | * 3) b.c.d.e.f | |
2431 | * 4) *.c.d.e.f | |
2432 | * 5) c.d.e.f | |
e926785a LP |
2433 | */ |
2434 | ||
2435 | for (;;) { | |
2436 | _cleanup_free_ char *wc = NULL; | |
2437 | bool a = false; | |
2438 | ||
2439 | /* Check if there's an NSEC or NSEC3 RR that proves that the mame we determined is really non-existing, | |
2440 | * i.e between the owner name and the next name of an NSEC RR. */ | |
2441 | r = dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC, name, zone, &a); | |
2442 | if (r <= 0) | |
2443 | return r; | |
2444 | ||
2445 | authenticated = authenticated && a; | |
2446 | ||
2447 | /* Strip one label off */ | |
2448 | r = dns_name_parent(&name); | |
2449 | if (r <= 0) | |
2450 | return r; | |
2451 | ||
2452 | /* Did we reach the source of synthesis? */ | |
2453 | r = dns_name_equal(name, source); | |
2454 | if (r < 0) | |
2455 | return r; | |
2456 | if (r > 0) { | |
2457 | /* Successful exit */ | |
2458 | *_authenticated = authenticated; | |
2459 | return 1; | |
2460 | } | |
2461 | ||
2462 | /* Safety check, that the source of synthesis is still our suffix */ | |
2463 | r = dns_name_endswith(name, source); | |
2464 | if (r < 0) | |
2465 | return r; | |
2466 | if (r == 0) | |
2467 | return -EBADMSG; | |
2468 | ||
2469 | /* Replace the label we stripped off with an asterisk */ | |
b910cc72 | 2470 | wc = strjoin("*.", name); |
e926785a LP |
2471 | if (!wc) |
2472 | return -ENOMEM; | |
2473 | ||
2474 | /* And check if the proof holds for the asterisk name, too */ | |
2475 | r = dnssec_nsec_test_enclosed(answer, DNS_TYPE_NSEC, wc, zone, &a); | |
2476 | if (r <= 0) | |
2477 | return r; | |
2478 | ||
2479 | authenticated = authenticated && a; | |
2480 | /* In the next iteration we'll check the non-asterisk-prefixed version */ | |
2481 | } | |
2482 | } | |
2483 | ||
2484 | int dnssec_test_positive_wildcard( | |
2485 | DnsAnswer *answer, | |
2486 | const char *name, | |
2487 | const char *source, | |
2488 | const char *zone, | |
2489 | bool *authenticated) { | |
2490 | ||
2491 | int r; | |
2492 | ||
2493 | assert(name); | |
2494 | assert(source); | |
2495 | assert(zone); | |
2496 | assert(authenticated); | |
2497 | ||
2498 | r = dns_answer_contains_zone_nsec3(answer, zone); | |
2499 | if (r < 0) | |
2500 | return r; | |
2501 | if (r > 0) | |
2502 | return dnssec_test_positive_wildcard_nsec3(answer, name, source, zone, authenticated); | |
2503 | else | |
2504 | return dnssec_test_positive_wildcard_nsec(answer, name, source, zone, authenticated); | |
2505 | } | |
2506 | ||
47091522 MO |
2507 | #else |
2508 | ||
2509 | int dnssec_verify_rrset( | |
2510 | DnsAnswer *a, | |
2511 | const DnsResourceKey *key, | |
2512 | DnsResourceRecord *rrsig, | |
2513 | DnsResourceRecord *dnskey, | |
2514 | usec_t realtime, | |
2515 | DnssecResult *result) { | |
2516 | ||
2517 | return -EOPNOTSUPP; | |
2518 | } | |
2519 | ||
2520 | int dnssec_rrsig_match_dnskey(DnsResourceRecord *rrsig, DnsResourceRecord *dnskey, bool revoked_ok) { | |
2521 | ||
2522 | return -EOPNOTSUPP; | |
2523 | } | |
2524 | ||
2525 | int dnssec_key_match_rrsig(const DnsResourceKey *key, DnsResourceRecord *rrsig) { | |
2526 | ||
2527 | return -EOPNOTSUPP; | |
2528 | } | |
2529 | ||
2530 | int dnssec_verify_rrset_search( | |
2531 | DnsAnswer *a, | |
2532 | const DnsResourceKey *key, | |
2533 | DnsAnswer *validated_dnskeys, | |
2534 | usec_t realtime, | |
2535 | DnssecResult *result, | |
2536 | DnsResourceRecord **ret_rrsig) { | |
2537 | ||
2538 | return -EOPNOTSUPP; | |
2539 | } | |
2540 | ||
2541 | int dnssec_has_rrsig(DnsAnswer *a, const DnsResourceKey *key) { | |
2542 | ||
2543 | return -EOPNOTSUPP; | |
2544 | } | |
2545 | ||
2546 | int dnssec_verify_dnskey_by_ds(DnsResourceRecord *dnskey, DnsResourceRecord *ds, bool mask_revoke) { | |
2547 | ||
2548 | return -EOPNOTSUPP; | |
2549 | } | |
2550 | ||
2551 | int dnssec_verify_dnskey_by_ds_search(DnsResourceRecord *dnskey, DnsAnswer *validated_ds) { | |
2552 | ||
2553 | return -EOPNOTSUPP; | |
2554 | } | |
2555 | ||
2556 | int dnssec_nsec3_hash(DnsResourceRecord *nsec3, const char *name, void *ret) { | |
2557 | ||
2558 | return -EOPNOTSUPP; | |
2559 | } | |
2560 | ||
2561 | int dnssec_nsec_test(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *result, bool *authenticated, uint32_t *ttl) { | |
2562 | ||
2563 | return -EOPNOTSUPP; | |
2564 | } | |
2565 | ||
2566 | int dnssec_test_positive_wildcard( | |
2567 | DnsAnswer *answer, | |
2568 | const char *name, | |
2569 | const char *source, | |
2570 | const char *zone, | |
2571 | bool *authenticated) { | |
2572 | ||
2573 | return -EOPNOTSUPP; | |
2574 | } | |
2575 | ||
2576 | #endif | |
2577 | ||
547973de | 2578 | static const char* const dnssec_result_table[_DNSSEC_RESULT_MAX] = { |
e3e64a1a ZJS |
2579 | [DNSSEC_VALIDATED] = "validated", |
2580 | [DNSSEC_VALIDATED_WILDCARD] = "validated-wildcard", | |
2581 | [DNSSEC_INVALID] = "invalid", | |
2582 | [DNSSEC_SIGNATURE_EXPIRED] = "signature-expired", | |
203f1b35 | 2583 | [DNSSEC_UNSUPPORTED_ALGORITHM] = "unsupported-algorithm", |
e3e64a1a ZJS |
2584 | [DNSSEC_NO_SIGNATURE] = "no-signature", |
2585 | [DNSSEC_MISSING_KEY] = "missing-key", | |
2586 | [DNSSEC_UNSIGNED] = "unsigned", | |
2587 | [DNSSEC_FAILED_AUXILIARY] = "failed-auxiliary", | |
2588 | [DNSSEC_NSEC_MISMATCH] = "nsec-mismatch", | |
2589 | [DNSSEC_INCOMPATIBLE_SERVER] = "incompatible-server", | |
a72cf22d | 2590 | [DNSSEC_UPSTREAM_FAILURE] = "upstream-failure", |
67d0ce88 | 2591 | [DNSSEC_TOO_MANY_VALIDATIONS] = "too-many-validations", |
547973de LP |
2592 | }; |
2593 | DEFINE_STRING_TABLE_LOOKUP(dnssec_result, DnssecResult); | |
59c5b597 LP |
2594 | |
2595 | static const char* const dnssec_verdict_table[_DNSSEC_VERDICT_MAX] = { | |
e3e64a1a ZJS |
2596 | [DNSSEC_SECURE] = "secure", |
2597 | [DNSSEC_INSECURE] = "insecure", | |
2598 | [DNSSEC_BOGUS] = "bogus", | |
59c5b597 LP |
2599 | [DNSSEC_INDETERMINATE] = "indeterminate", |
2600 | }; | |
2601 | DEFINE_STRING_TABLE_LOOKUP(dnssec_verdict, DnssecVerdict); |