1 /*
2 * validator/val_secalgo.c - validator security algorithm functions.
3 *
4 * Copyright (c) 2012, NLnet Labs. All rights reserved.
5 *
6 * This software is open source.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * Redistributions of source code must retain the above copyright notice,
13 * this list of conditions and the following disclaimer.
14 *
15 * Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 *
19 * Neither the name of the NLNET LABS nor the names of its contributors may
20 * be used to endorse or promote products derived from this software without
21 * specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 /**
37 * \file
38 *
39 * This file contains helper functions for the validator module.
40 * These functions take raw data buffers, formatted for crypto verification,
41 * and do the library calls (for the crypto library in use).
42 */
43 #include "config.h"
44 /* packed_rrset on top to define enum types (forced by c99 standard) */
45 #include "util/data/packed_rrset.h"
46 #include "validator/val_secalgo.h"
47 #include "validator/val_nsec3.h"
48 #include "util/log.h"
49 #include "sldns/rrdef.h"
50 #include "sldns/keyraw.h"
51 #include "sldns/sbuffer.h"
52
53 #if !defined(HAVE_SSL) && !defined(HAVE_NSS) && !defined(HAVE_NETTLE)
54 #error "Need crypto library to do digital signature cryptography"
55 #endif
56
57 /** fake DSA support for unit tests */
58 int fake_dsa = 0;
59 /** fake SHA1 support for unit tests */
60 int fake_sha1 = 0;
61
62 /* OpenSSL implementation */
63 #ifdef HAVE_SSL
64 #ifdef HAVE_OPENSSL_ERR_H
65 #include <openssl/err.h>
66 #endif
67
68 #ifdef HAVE_OPENSSL_RAND_H
69 #include <openssl/rand.h>
70 #endif
71
72 #ifdef HAVE_OPENSSL_CONF_H
73 #include <openssl/conf.h>
74 #endif
75
76 #ifdef HAVE_OPENSSL_ENGINE_H
77 #include <openssl/engine.h>
78 #endif
79
80 #if defined(HAVE_OPENSSL_DSA_H) && defined(USE_DSA)
81 #include <openssl/dsa.h>
82 #endif
83
84 /**
85 * Output a libcrypto openssl error to the logfile.
86 * @param str: string to add to it.
87 * @param e: the error to output, error number from ERR_get_error().
88 */
89 static void
log_crypto_error(const char * str,unsigned long e)90 log_crypto_error(const char* str, unsigned long e)
91 {
92 char buf[128];
93 /* or use ERR_error_string if ERR_error_string_n is not avail TODO */
94 ERR_error_string_n(e, buf, sizeof(buf));
95 /* buf now contains */
96 /* error:[error code]:[library name]:[function name]:[reason string] */
97 log_err("%s crypto %s", str, buf);
98 }
99
100 /* return size of digest if supported, or 0 otherwise */
101 size_t
nsec3_hash_algo_size_supported(int id)102 nsec3_hash_algo_size_supported(int id)
103 {
104 switch(id) {
105 case NSEC3_HASH_SHA1:
106 return SHA_DIGEST_LENGTH;
107 default:
108 return 0;
109 }
110 }
111
112 /* perform nsec3 hash. return false on failure */
113 int
secalgo_nsec3_hash(int algo,unsigned char * buf,size_t len,unsigned char * res)114 secalgo_nsec3_hash(int algo, unsigned char* buf, size_t len,
115 unsigned char* res)
116 {
117 switch(algo) {
118 case NSEC3_HASH_SHA1:
119 #ifdef OPENSSL_FIPS
120 if(!sldns_digest_evp(buf, len, res, EVP_sha1()))
121 log_crypto_error("could not digest with EVP_sha1",
122 ERR_get_error());
123 #else
124 (void)SHA1(buf, len, res);
125 #endif
126 return 1;
127 default:
128 return 0;
129 }
130 }
131
132 void
secalgo_hash_sha256(unsigned char * buf,size_t len,unsigned char * res)133 secalgo_hash_sha256(unsigned char* buf, size_t len, unsigned char* res)
134 {
135 #ifdef OPENSSL_FIPS
136 if(!sldns_digest_evp(buf, len, res, EVP_sha256()))
137 log_crypto_error("could not digest with EVP_sha256",
138 ERR_get_error());
139 #else
140 (void)SHA256(buf, len, res);
141 #endif
142 }
143
144 /** hash structure for keeping track of running hashes */
145 struct secalgo_hash {
146 /** the openssl message digest context */
147 EVP_MD_CTX* ctx;
148 };
149
150 /** create secalgo hash with hash type */
secalgo_hash_create_md(const EVP_MD * md)151 static struct secalgo_hash* secalgo_hash_create_md(const EVP_MD* md)
152 {
153 struct secalgo_hash* h;
154 if(!md)
155 return NULL;
156 h = calloc(1, sizeof(*h));
157 if(!h)
158 return NULL;
159 h->ctx = EVP_MD_CTX_create();
160 if(!h->ctx) {
161 free(h);
162 return NULL;
163 }
164 if(!EVP_DigestInit_ex(h->ctx, md, NULL)) {
165 EVP_MD_CTX_destroy(h->ctx);
166 free(h);
167 return NULL;
168 }
169 return h;
170 }
171
secalgo_hash_create_sha384(void)172 struct secalgo_hash* secalgo_hash_create_sha384(void)
173 {
174 return secalgo_hash_create_md(EVP_sha384());
175 }
176
secalgo_hash_create_sha512(void)177 struct secalgo_hash* secalgo_hash_create_sha512(void)
178 {
179 return secalgo_hash_create_md(EVP_sha512());
180 }
181
secalgo_hash_update(struct secalgo_hash * hash,uint8_t * data,size_t len)182 int secalgo_hash_update(struct secalgo_hash* hash, uint8_t* data, size_t len)
183 {
184 return EVP_DigestUpdate(hash->ctx, (unsigned char*)data,
185 (unsigned int)len);
186 }
187
secalgo_hash_final(struct secalgo_hash * hash,uint8_t * result,size_t maxlen,size_t * resultlen)188 int secalgo_hash_final(struct secalgo_hash* hash, uint8_t* result,
189 size_t maxlen, size_t* resultlen)
190 {
191 if(EVP_MD_CTX_size(hash->ctx) > (int)maxlen) {
192 *resultlen = 0;
193 log_err("secalgo_hash_final: hash buffer too small");
194 return 0;
195 }
196 *resultlen = EVP_MD_CTX_size(hash->ctx);
197 return EVP_DigestFinal_ex(hash->ctx, result, NULL);
198 }
199
secalgo_hash_delete(struct secalgo_hash * hash)200 void secalgo_hash_delete(struct secalgo_hash* hash)
201 {
202 if(!hash) return;
203 EVP_MD_CTX_destroy(hash->ctx);
204 free(hash);
205 }
206
207 /**
208 * Return size of DS digest according to its hash algorithm.
209 * @param algo: DS digest algo.
210 * @return size in bytes of digest, or 0 if not supported.
211 */
212 size_t
ds_digest_size_supported(int algo)213 ds_digest_size_supported(int algo)
214 {
215 switch(algo) {
216 case LDNS_SHA1:
217 #if defined(HAVE_EVP_SHA1) && defined(USE_SHA1)
218 return SHA_DIGEST_LENGTH;
219 #else
220 if(fake_sha1) return 20;
221 return 0;
222 #endif
223 #ifdef HAVE_EVP_SHA256
224 case LDNS_SHA256:
225 return SHA256_DIGEST_LENGTH;
226 #endif
227 #ifdef USE_GOST
228 case LDNS_HASH_GOST:
229 /* we support GOST if it can be loaded */
230 (void)sldns_key_EVP_load_gost_id();
231 if(EVP_get_digestbyname("md_gost94"))
232 return 32;
233 else return 0;
234 #endif
235 #ifdef USE_ECDSA
236 case LDNS_SHA384:
237 return SHA384_DIGEST_LENGTH;
238 #endif
239 default: break;
240 }
241 return 0;
242 }
243
244 #ifdef USE_GOST
245 /** Perform GOST hash */
246 static int
do_gost94(unsigned char * data,size_t len,unsigned char * dest)247 do_gost94(unsigned char* data, size_t len, unsigned char* dest)
248 {
249 const EVP_MD* md = EVP_get_digestbyname("md_gost94");
250 if(!md)
251 return 0;
252 return sldns_digest_evp(data, (unsigned int)len, dest, md);
253 }
254 #endif
255
256 int
secalgo_ds_digest(int algo,unsigned char * buf,size_t len,unsigned char * res)257 secalgo_ds_digest(int algo, unsigned char* buf, size_t len,
258 unsigned char* res)
259 {
260 switch(algo) {
261 #if defined(HAVE_EVP_SHA1) && defined(USE_SHA1)
262 case LDNS_SHA1:
263 #ifdef OPENSSL_FIPS
264 if(!sldns_digest_evp(buf, len, res, EVP_sha1()))
265 log_crypto_error("could not digest with EVP_sha1",
266 ERR_get_error());
267 #else
268 (void)SHA1(buf, len, res);
269 #endif
270 return 1;
271 #endif
272 #ifdef HAVE_EVP_SHA256
273 case LDNS_SHA256:
274 #ifdef OPENSSL_FIPS
275 if(!sldns_digest_evp(buf, len, res, EVP_sha256()))
276 log_crypto_error("could not digest with EVP_sha256",
277 ERR_get_error());
278 #else
279 (void)SHA256(buf, len, res);
280 #endif
281 return 1;
282 #endif
283 #ifdef USE_GOST
284 case LDNS_HASH_GOST:
285 if(do_gost94(buf, len, res))
286 return 1;
287 break;
288 #endif
289 #ifdef USE_ECDSA
290 case LDNS_SHA384:
291 #ifdef OPENSSL_FIPS
292 if(!sldns_digest_evp(buf, len, res, EVP_sha384()))
293 log_crypto_error("could not digest with EVP_sha384",
294 ERR_get_error());
295 #else
296 (void)SHA384(buf, len, res);
297 #endif
298 return 1;
299 #endif
300 default:
301 verbose(VERB_QUERY, "unknown DS digest algorithm %d",
302 algo);
303 break;
304 }
305 return 0;
306 }
307
308 /** return true if DNSKEY algorithm id is supported */
309 int
dnskey_algo_id_is_supported(int id)310 dnskey_algo_id_is_supported(int id)
311 {
312 switch(id) {
313 case LDNS_RSAMD5:
314 /* RFC 6725 deprecates RSAMD5 */
315 return 0;
316 case LDNS_DSA:
317 case LDNS_DSA_NSEC3:
318 #if defined(USE_DSA) && defined(USE_SHA1)
319 return 1;
320 #else
321 if(fake_dsa || fake_sha1) return 1;
322 return 0;
323 #endif
324
325 case LDNS_RSASHA1:
326 case LDNS_RSASHA1_NSEC3:
327 #ifdef USE_SHA1
328 return 1;
329 #else
330 if(fake_sha1) return 1;
331 return 0;
332 #endif
333
334 #if defined(HAVE_EVP_SHA256) && defined(USE_SHA2)
335 case LDNS_RSASHA256:
336 #endif
337 #if defined(HAVE_EVP_SHA512) && defined(USE_SHA2)
338 case LDNS_RSASHA512:
339 #endif
340 #ifdef USE_ECDSA
341 case LDNS_ECDSAP256SHA256:
342 case LDNS_ECDSAP384SHA384:
343 #endif
344 #ifdef USE_ED25519
345 case LDNS_ED25519:
346 #endif
347 #ifdef USE_ED448
348 case LDNS_ED448:
349 #endif
350 #if (defined(HAVE_EVP_SHA256) && defined(USE_SHA2)) || (defined(HAVE_EVP_SHA512) && defined(USE_SHA2)) || defined(USE_ECDSA) || defined(USE_ED25519) || defined(USE_ED448)
351 return 1;
352 #endif
353
354 #ifdef USE_GOST
355 case LDNS_ECC_GOST:
356 /* we support GOST if it can be loaded */
357 return sldns_key_EVP_load_gost_id();
358 #endif
359 default:
360 return 0;
361 }
362 }
363
364 #ifdef USE_DSA
365 /**
366 * Setup DSA key digest in DER encoding ...
367 * @param sig: input is signature output alloced ptr (unless failure).
368 * caller must free alloced ptr if this routine returns true.
369 * @param len: input is initial siglen, output is output len.
370 * @return false on failure.
371 */
372 static int
setup_dsa_sig(unsigned char ** sig,unsigned int * len)373 setup_dsa_sig(unsigned char** sig, unsigned int* len)
374 {
375 unsigned char* orig = *sig;
376 unsigned int origlen = *len;
377 int newlen;
378 BIGNUM *R, *S;
379 DSA_SIG *dsasig;
380
381 /* extract the R and S field from the sig buffer */
382 if(origlen < 1 + 2*SHA_DIGEST_LENGTH)
383 return 0;
384 R = BN_new();
385 if(!R) return 0;
386 (void) BN_bin2bn(orig + 1, SHA_DIGEST_LENGTH, R);
387 S = BN_new();
388 if(!S) return 0;
389 (void) BN_bin2bn(orig + 21, SHA_DIGEST_LENGTH, S);
390 dsasig = DSA_SIG_new();
391 if(!dsasig) return 0;
392
393 #ifdef HAVE_DSA_SIG_SET0
394 if(!DSA_SIG_set0(dsasig, R, S)) return 0;
395 #else
396 # ifndef S_SPLINT_S
397 dsasig->r = R;
398 dsasig->s = S;
399 # endif /* S_SPLINT_S */
400 #endif
401 *sig = NULL;
402 newlen = i2d_DSA_SIG(dsasig, sig);
403 if(newlen < 0) {
404 DSA_SIG_free(dsasig);
405 free(*sig);
406 return 0;
407 }
408 *len = (unsigned int)newlen;
409 DSA_SIG_free(dsasig);
410 return 1;
411 }
412 #endif /* USE_DSA */
413
414 #ifdef USE_ECDSA
415 /**
416 * Setup the ECDSA signature in its encoding that the library wants.
417 * Converts from plain numbers to ASN formatted.
418 * @param sig: input is signature, output alloced ptr (unless failure).
419 * caller must free alloced ptr if this routine returns true.
420 * @param len: input is initial siglen, output is output len.
421 * @return false on failure.
422 */
423 static int
setup_ecdsa_sig(unsigned char ** sig,unsigned int * len)424 setup_ecdsa_sig(unsigned char** sig, unsigned int* len)
425 {
426 /* convert from two BIGNUMs in the rdata buffer, to ASN notation.
427 * ASN preamble: 30440220 <R 32bytefor256> 0220 <S 32bytefor256>
428 * the '20' is the length of that field (=bnsize).
429 i * the '44' is the total remaining length.
430 * if negative, start with leading zero.
431 * if starts with 00s, remove them from the number.
432 */
433 uint8_t pre[] = {0x30, 0x44, 0x02, 0x20};
434 int pre_len = 4;
435 uint8_t mid[] = {0x02, 0x20};
436 int mid_len = 2;
437 int raw_sig_len, r_high, s_high, r_rem=0, s_rem=0;
438 int bnsize = (int)((*len)/2);
439 unsigned char* d = *sig;
440 uint8_t* p;
441 /* if too short or not even length, fails */
442 if(*len < 16 || bnsize*2 != (int)*len)
443 return 0;
444
445 /* strip leading zeroes from r (but not last one) */
446 while(r_rem < bnsize-1 && d[r_rem] == 0)
447 r_rem++;
448 /* strip leading zeroes from s (but not last one) */
449 while(s_rem < bnsize-1 && d[bnsize+s_rem] == 0)
450 s_rem++;
451
452 r_high = ((d[0+r_rem]&0x80)?1:0);
453 s_high = ((d[bnsize+s_rem]&0x80)?1:0);
454 raw_sig_len = pre_len + r_high + bnsize - r_rem + mid_len +
455 s_high + bnsize - s_rem;
456 *sig = (unsigned char*)malloc((size_t)raw_sig_len);
457 if(!*sig)
458 return 0;
459 p = (uint8_t*)*sig;
460 p[0] = pre[0];
461 p[1] = (uint8_t)(raw_sig_len-2);
462 p[2] = pre[2];
463 p[3] = (uint8_t)(bnsize + r_high - r_rem);
464 p += 4;
465 if(r_high) {
466 *p = 0;
467 p += 1;
468 }
469 memmove(p, d+r_rem, (size_t)bnsize-r_rem);
470 p += bnsize-r_rem;
471 memmove(p, mid, (size_t)mid_len-1);
472 p += mid_len-1;
473 *p = (uint8_t)(bnsize + s_high - s_rem);
474 p += 1;
475 if(s_high) {
476 *p = 0;
477 p += 1;
478 }
479 memmove(p, d+bnsize+s_rem, (size_t)bnsize-s_rem);
480 *len = (unsigned int)raw_sig_len;
481 return 1;
482 }
483 #endif /* USE_ECDSA */
484
485 #ifdef USE_ECDSA_EVP_WORKAROUND
486 static EVP_MD ecdsa_evp_256_md;
487 static EVP_MD ecdsa_evp_384_md;
ecdsa_evp_workaround_init(void)488 void ecdsa_evp_workaround_init(void)
489 {
490 /* openssl before 1.0.0 fixes RSA with the SHA256
491 * hash in EVP. We create one for ecdsa_sha256 */
492 ecdsa_evp_256_md = *EVP_sha256();
493 ecdsa_evp_256_md.required_pkey_type[0] = EVP_PKEY_EC;
494 ecdsa_evp_256_md.verify = (void*)ECDSA_verify;
495
496 ecdsa_evp_384_md = *EVP_sha384();
497 ecdsa_evp_384_md.required_pkey_type[0] = EVP_PKEY_EC;
498 ecdsa_evp_384_md.verify = (void*)ECDSA_verify;
499 }
500 #endif /* USE_ECDSA_EVP_WORKAROUND */
501
502 /**
503 * Setup key and digest for verification. Adjust sig if necessary.
504 *
505 * @param algo: key algorithm
506 * @param evp_key: EVP PKEY public key to create.
507 * @param digest_type: digest type to use
508 * @param key: key to setup for.
509 * @param keylen: length of key.
510 * @return false on failure.
511 */
512 static int
setup_key_digest(int algo,EVP_PKEY ** evp_key,const EVP_MD ** digest_type,unsigned char * key,size_t keylen)513 setup_key_digest(int algo, EVP_PKEY** evp_key, const EVP_MD** digest_type,
514 unsigned char* key, size_t keylen)
515 {
516 switch(algo) {
517 #if defined(USE_DSA) && defined(USE_SHA1)
518 case LDNS_DSA:
519 case LDNS_DSA_NSEC3:
520 *evp_key = sldns_key_dsa2pkey_raw(key, keylen);
521 if(!*evp_key) {
522 verbose(VERB_QUERY, "verify: sldns_key_dsa2pkey failed");
523 return 0;
524 }
525 #ifdef HAVE_EVP_DSS1
526 *digest_type = EVP_dss1();
527 #else
528 *digest_type = EVP_sha1();
529 #endif
530
531 break;
532 #endif /* USE_DSA && USE_SHA1 */
533
534 #if defined(USE_SHA1) || (defined(HAVE_EVP_SHA256) && defined(USE_SHA2)) || (defined(HAVE_EVP_SHA512) && defined(USE_SHA2))
535 #ifdef USE_SHA1
536 case LDNS_RSASHA1:
537 case LDNS_RSASHA1_NSEC3:
538 #endif
539 #if defined(HAVE_EVP_SHA256) && defined(USE_SHA2)
540 case LDNS_RSASHA256:
541 #endif
542 #if defined(HAVE_EVP_SHA512) && defined(USE_SHA2)
543 case LDNS_RSASHA512:
544 #endif
545 *evp_key = sldns_key_rsa2pkey_raw(key, keylen);
546 if(!*evp_key) {
547 verbose(VERB_QUERY, "verify: sldns_key_rsa2pkey SHA failed");
548 return 0;
549 }
550
551 /* select SHA version */
552 #if defined(HAVE_EVP_SHA256) && defined(USE_SHA2)
553 if(algo == LDNS_RSASHA256)
554 *digest_type = EVP_sha256();
555 else
556 #endif
557 #if defined(HAVE_EVP_SHA512) && defined(USE_SHA2)
558 if(algo == LDNS_RSASHA512)
559 *digest_type = EVP_sha512();
560 else
561 #endif
562 #ifdef USE_SHA1
563 *digest_type = EVP_sha1();
564 #else
565 { verbose(VERB_QUERY, "no digest available"); return 0; }
566 #endif
567 break;
568 #endif /* defined(USE_SHA1) || (defined(HAVE_EVP_SHA256) && defined(USE_SHA2)) || (defined(HAVE_EVP_SHA512) && defined(USE_SHA2)) */
569
570 case LDNS_RSAMD5:
571 *evp_key = sldns_key_rsa2pkey_raw(key, keylen);
572 if(!*evp_key) {
573 verbose(VERB_QUERY, "verify: sldns_key_rsa2pkey MD5 failed");
574 return 0;
575 }
576 *digest_type = EVP_md5();
577
578 break;
579 #ifdef USE_GOST
580 case LDNS_ECC_GOST:
581 *evp_key = sldns_gost2pkey_raw(key, keylen);
582 if(!*evp_key) {
583 verbose(VERB_QUERY, "verify: "
584 "sldns_gost2pkey_raw failed");
585 return 0;
586 }
587 *digest_type = EVP_get_digestbyname("md_gost94");
588 if(!*digest_type) {
589 verbose(VERB_QUERY, "verify: "
590 "EVP_getdigest md_gost94 failed");
591 return 0;
592 }
593 break;
594 #endif
595 #ifdef USE_ECDSA
596 case LDNS_ECDSAP256SHA256:
597 *evp_key = sldns_ecdsa2pkey_raw(key, keylen,
598 LDNS_ECDSAP256SHA256);
599 if(!*evp_key) {
600 verbose(VERB_QUERY, "verify: "
601 "sldns_ecdsa2pkey_raw failed");
602 return 0;
603 }
604 #ifdef USE_ECDSA_EVP_WORKAROUND
605 *digest_type = &ecdsa_evp_256_md;
606 #else
607 *digest_type = EVP_sha256();
608 #endif
609 break;
610 case LDNS_ECDSAP384SHA384:
611 *evp_key = sldns_ecdsa2pkey_raw(key, keylen,
612 LDNS_ECDSAP384SHA384);
613 if(!*evp_key) {
614 verbose(VERB_QUERY, "verify: "
615 "sldns_ecdsa2pkey_raw failed");
616 return 0;
617 }
618 #ifdef USE_ECDSA_EVP_WORKAROUND
619 *digest_type = &ecdsa_evp_384_md;
620 #else
621 *digest_type = EVP_sha384();
622 #endif
623 break;
624 #endif /* USE_ECDSA */
625 #ifdef USE_ED25519
626 case LDNS_ED25519:
627 *evp_key = sldns_ed255192pkey_raw(key, keylen);
628 if(!*evp_key) {
629 verbose(VERB_QUERY, "verify: "
630 "sldns_ed255192pkey_raw failed");
631 return 0;
632 }
633 *digest_type = NULL;
634 break;
635 #endif /* USE_ED25519 */
636 #ifdef USE_ED448
637 case LDNS_ED448:
638 *evp_key = sldns_ed4482pkey_raw(key, keylen);
639 if(!*evp_key) {
640 verbose(VERB_QUERY, "verify: "
641 "sldns_ed4482pkey_raw failed");
642 return 0;
643 }
644 *digest_type = NULL;
645 break;
646 #endif /* USE_ED448 */
647 default:
648 verbose(VERB_QUERY, "verify: unknown algorithm %d",
649 algo);
650 return 0;
651 }
652 return 1;
653 }
654
655 /**
656 * Check a canonical sig+rrset and signature against a dnskey
657 * @param buf: buffer with data to verify, the first rrsig part and the
658 * canonicalized rrset.
659 * @param algo: DNSKEY algorithm.
660 * @param sigblock: signature rdata field from RRSIG
661 * @param sigblock_len: length of sigblock data.
662 * @param key: public key data from DNSKEY RR.
663 * @param keylen: length of keydata.
664 * @param reason: bogus reason in more detail.
665 * @return secure if verification succeeded, bogus on crypto failure,
666 * unchecked on format errors and alloc failures.
667 */
668 enum sec_status
verify_canonrrset(sldns_buffer * buf,int algo,unsigned char * sigblock,unsigned int sigblock_len,unsigned char * key,unsigned int keylen,char ** reason)669 verify_canonrrset(sldns_buffer* buf, int algo, unsigned char* sigblock,
670 unsigned int sigblock_len, unsigned char* key, unsigned int keylen,
671 char** reason)
672 {
673 const EVP_MD *digest_type;
674 EVP_MD_CTX* ctx;
675 int res, dofree = 0, docrypto_free = 0;
676 EVP_PKEY *evp_key = NULL;
677
678 #ifndef USE_DSA
679 if((algo == LDNS_DSA || algo == LDNS_DSA_NSEC3) &&(fake_dsa||fake_sha1))
680 return sec_status_secure;
681 #endif
682 #ifndef USE_SHA1
683 if(fake_sha1 && (algo == LDNS_DSA || algo == LDNS_DSA_NSEC3 || algo == LDNS_RSASHA1 || algo == LDNS_RSASHA1_NSEC3))
684 return sec_status_secure;
685 #endif
686
687 if(!setup_key_digest(algo, &evp_key, &digest_type, key, keylen)) {
688 verbose(VERB_QUERY, "verify: failed to setup key");
689 *reason = "use of key for crypto failed";
690 EVP_PKEY_free(evp_key);
691 return sec_status_bogus;
692 }
693 #ifdef USE_DSA
694 /* if it is a DSA signature in bind format, convert to DER format */
695 if((algo == LDNS_DSA || algo == LDNS_DSA_NSEC3) &&
696 sigblock_len == 1+2*SHA_DIGEST_LENGTH) {
697 if(!setup_dsa_sig(&sigblock, &sigblock_len)) {
698 verbose(VERB_QUERY, "verify: failed to setup DSA sig");
699 *reason = "use of key for DSA crypto failed";
700 EVP_PKEY_free(evp_key);
701 return sec_status_bogus;
702 }
703 docrypto_free = 1;
704 }
705 #endif
706 #if defined(USE_ECDSA) && defined(USE_DSA)
707 else
708 #endif
709 #ifdef USE_ECDSA
710 if(algo == LDNS_ECDSAP256SHA256 || algo == LDNS_ECDSAP384SHA384) {
711 /* EVP uses ASN prefix on sig, which is not in the wire data */
712 if(!setup_ecdsa_sig(&sigblock, &sigblock_len)) {
713 verbose(VERB_QUERY, "verify: failed to setup ECDSA sig");
714 *reason = "use of signature for ECDSA crypto failed";
715 EVP_PKEY_free(evp_key);
716 return sec_status_bogus;
717 }
718 dofree = 1;
719 }
720 #endif /* USE_ECDSA */
721
722 /* do the signature cryptography work */
723 #ifdef HAVE_EVP_MD_CTX_NEW
724 ctx = EVP_MD_CTX_new();
725 #else
726 ctx = (EVP_MD_CTX*)malloc(sizeof(*ctx));
727 if(ctx) EVP_MD_CTX_init(ctx);
728 #endif
729 if(!ctx) {
730 log_err("EVP_MD_CTX_new: malloc failure");
731 EVP_PKEY_free(evp_key);
732 if(dofree) free(sigblock);
733 else if(docrypto_free) OPENSSL_free(sigblock);
734 return sec_status_unchecked;
735 }
736 #ifndef HAVE_EVP_DIGESTVERIFY
737 if(EVP_DigestInit(ctx, digest_type) == 0) {
738 verbose(VERB_QUERY, "verify: EVP_DigestInit failed");
739 #ifdef HAVE_EVP_MD_CTX_NEW
740 EVP_MD_CTX_destroy(ctx);
741 #else
742 EVP_MD_CTX_cleanup(ctx);
743 free(ctx);
744 #endif
745 EVP_PKEY_free(evp_key);
746 if(dofree) free(sigblock);
747 else if(docrypto_free) OPENSSL_free(sigblock);
748 return sec_status_unchecked;
749 }
750 if(EVP_DigestUpdate(ctx, (unsigned char*)sldns_buffer_begin(buf),
751 (unsigned int)sldns_buffer_limit(buf)) == 0) {
752 verbose(VERB_QUERY, "verify: EVP_DigestUpdate failed");
753 #ifdef HAVE_EVP_MD_CTX_NEW
754 EVP_MD_CTX_destroy(ctx);
755 #else
756 EVP_MD_CTX_cleanup(ctx);
757 free(ctx);
758 #endif
759 EVP_PKEY_free(evp_key);
760 if(dofree) free(sigblock);
761 else if(docrypto_free) OPENSSL_free(sigblock);
762 return sec_status_unchecked;
763 }
764
765 res = EVP_VerifyFinal(ctx, sigblock, sigblock_len, evp_key);
766 #else /* HAVE_EVP_DIGESTVERIFY */
767 if(EVP_DigestVerifyInit(ctx, NULL, digest_type, NULL, evp_key) == 0) {
768 verbose(VERB_QUERY, "verify: EVP_DigestVerifyInit failed");
769 #ifdef HAVE_EVP_MD_CTX_NEW
770 EVP_MD_CTX_destroy(ctx);
771 #else
772 EVP_MD_CTX_cleanup(ctx);
773 free(ctx);
774 #endif
775 EVP_PKEY_free(evp_key);
776 if(dofree) free(sigblock);
777 else if(docrypto_free) OPENSSL_free(sigblock);
778 return sec_status_unchecked;
779 }
780 res = EVP_DigestVerify(ctx, sigblock, sigblock_len,
781 (unsigned char*)sldns_buffer_begin(buf),
782 sldns_buffer_limit(buf));
783 #endif
784 #ifdef HAVE_EVP_MD_CTX_NEW
785 EVP_MD_CTX_destroy(ctx);
786 #else
787 EVP_MD_CTX_cleanup(ctx);
788 free(ctx);
789 #endif
790 EVP_PKEY_free(evp_key);
791
792 if(dofree) free(sigblock);
793 else if(docrypto_free) OPENSSL_free(sigblock);
794
795 if(res == 1) {
796 return sec_status_secure;
797 } else if(res == 0) {
798 verbose(VERB_QUERY, "verify: signature mismatch");
799 *reason = "signature crypto failed";
800 return sec_status_bogus;
801 }
802
803 log_crypto_error("verify:", ERR_get_error());
804 return sec_status_unchecked;
805 }
806
807 /**************************************************/
808 #elif defined(HAVE_NSS)
809 /* libnss implementation */
810 /* nss3 */
811 #include "sechash.h"
812 #include "pk11pub.h"
813 #include "keyhi.h"
814 #include "secerr.h"
815 #include "cryptohi.h"
816 /* nspr4 */
817 #include "prerror.h"
818
819 /* return size of digest if supported, or 0 otherwise */
820 size_t
nsec3_hash_algo_size_supported(int id)821 nsec3_hash_algo_size_supported(int id)
822 {
823 switch(id) {
824 case NSEC3_HASH_SHA1:
825 return SHA1_LENGTH;
826 default:
827 return 0;
828 }
829 }
830
831 /* perform nsec3 hash. return false on failure */
832 int
secalgo_nsec3_hash(int algo,unsigned char * buf,size_t len,unsigned char * res)833 secalgo_nsec3_hash(int algo, unsigned char* buf, size_t len,
834 unsigned char* res)
835 {
836 switch(algo) {
837 case NSEC3_HASH_SHA1:
838 (void)HASH_HashBuf(HASH_AlgSHA1, res, buf, (unsigned long)len);
839 return 1;
840 default:
841 return 0;
842 }
843 }
844
845 void
secalgo_hash_sha256(unsigned char * buf,size_t len,unsigned char * res)846 secalgo_hash_sha256(unsigned char* buf, size_t len, unsigned char* res)
847 {
848 (void)HASH_HashBuf(HASH_AlgSHA256, res, buf, (unsigned long)len);
849 }
850
851 /** the secalgo hash structure */
852 struct secalgo_hash {
853 /** hash context */
854 HASHContext* ctx;
855 };
856
857 /** create hash struct of type */
secalgo_hash_create_type(HASH_HashType tp)858 static struct secalgo_hash* secalgo_hash_create_type(HASH_HashType tp)
859 {
860 struct secalgo_hash* h = calloc(1, sizeof(*h));
861 if(!h)
862 return NULL;
863 h->ctx = HASH_Create(tp);
864 if(!h->ctx) {
865 free(h);
866 return NULL;
867 }
868 return h;
869 }
870
secalgo_hash_create_sha384(void)871 struct secalgo_hash* secalgo_hash_create_sha384(void)
872 {
873 return secalgo_hash_create_type(HASH_AlgSHA384);
874 }
875
secalgo_hash_create_sha512(void)876 struct secalgo_hash* secalgo_hash_create_sha512(void)
877 {
878 return secalgo_hash_create_type(HASH_AlgSHA512);
879 }
880
secalgo_hash_update(struct secalgo_hash * hash,uint8_t * data,size_t len)881 int secalgo_hash_update(struct secalgo_hash* hash, uint8_t* data, size_t len)
882 {
883 HASH_Update(hash->ctx, (unsigned char*)data, (unsigned int)len);
884 return 1;
885 }
886
secalgo_hash_final(struct secalgo_hash * hash,uint8_t * result,size_t maxlen,size_t * resultlen)887 int secalgo_hash_final(struct secalgo_hash* hash, uint8_t* result,
888 size_t maxlen, size_t* resultlen)
889 {
890 unsigned int reslen = 0;
891 if(HASH_ResultLenContext(hash->ctx) > (unsigned int)maxlen) {
892 *resultlen = 0;
893 log_err("secalgo_hash_final: hash buffer too small");
894 return 0;
895 }
896 HASH_End(hash->ctx, (unsigned char*)result, &reslen,
897 (unsigned int)maxlen);
898 *resultlen = (size_t)reslen;
899 return 1;
900 }
901
secalgo_hash_delete(struct secalgo_hash * hash)902 void secalgo_hash_delete(struct secalgo_hash* hash)
903 {
904 if(!hash) return;
905 HASH_Destroy(hash->ctx);
906 free(hash);
907 }
908
909 size_t
ds_digest_size_supported(int algo)910 ds_digest_size_supported(int algo)
911 {
912 /* uses libNSS */
913 switch(algo) {
914 #ifdef USE_SHA1
915 case LDNS_SHA1:
916 return SHA1_LENGTH;
917 #endif
918 #ifdef USE_SHA2
919 case LDNS_SHA256:
920 return SHA256_LENGTH;
921 #endif
922 #ifdef USE_ECDSA
923 case LDNS_SHA384:
924 return SHA384_LENGTH;
925 #endif
926 /* GOST not supported in NSS */
927 case LDNS_HASH_GOST:
928 default: break;
929 }
930 return 0;
931 }
932
933 int
secalgo_ds_digest(int algo,unsigned char * buf,size_t len,unsigned char * res)934 secalgo_ds_digest(int algo, unsigned char* buf, size_t len,
935 unsigned char* res)
936 {
937 /* uses libNSS */
938 switch(algo) {
939 #ifdef USE_SHA1
940 case LDNS_SHA1:
941 return HASH_HashBuf(HASH_AlgSHA1, res, buf, len)
942 == SECSuccess;
943 #endif
944 #if defined(USE_SHA2)
945 case LDNS_SHA256:
946 return HASH_HashBuf(HASH_AlgSHA256, res, buf, len)
947 == SECSuccess;
948 #endif
949 #ifdef USE_ECDSA
950 case LDNS_SHA384:
951 return HASH_HashBuf(HASH_AlgSHA384, res, buf, len)
952 == SECSuccess;
953 #endif
954 case LDNS_HASH_GOST:
955 default:
956 verbose(VERB_QUERY, "unknown DS digest algorithm %d",
957 algo);
958 break;
959 }
960 return 0;
961 }
962
963 int
dnskey_algo_id_is_supported(int id)964 dnskey_algo_id_is_supported(int id)
965 {
966 /* uses libNSS */
967 switch(id) {
968 case LDNS_RSAMD5:
969 /* RFC 6725 deprecates RSAMD5 */
970 return 0;
971 #if defined(USE_SHA1) || defined(USE_SHA2)
972 #if defined(USE_DSA) && defined(USE_SHA1)
973 case LDNS_DSA:
974 case LDNS_DSA_NSEC3:
975 #endif
976 #ifdef USE_SHA1
977 case LDNS_RSASHA1:
978 case LDNS_RSASHA1_NSEC3:
979 #endif
980 #ifdef USE_SHA2
981 case LDNS_RSASHA256:
982 #endif
983 #ifdef USE_SHA2
984 case LDNS_RSASHA512:
985 #endif
986 return 1;
987 #endif /* SHA1 or SHA2 */
988
989 #ifdef USE_ECDSA
990 case LDNS_ECDSAP256SHA256:
991 case LDNS_ECDSAP384SHA384:
992 return PK11_TokenExists(CKM_ECDSA);
993 #endif
994 case LDNS_ECC_GOST:
995 default:
996 return 0;
997 }
998 }
999
1000 /* return a new public key for NSS */
nss_key_create(KeyType ktype)1001 static SECKEYPublicKey* nss_key_create(KeyType ktype)
1002 {
1003 SECKEYPublicKey* key;
1004 PLArenaPool* arena = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);
1005 if(!arena) {
1006 log_err("out of memory, PORT_NewArena failed");
1007 return NULL;
1008 }
1009 key = PORT_ArenaZNew(arena, SECKEYPublicKey);
1010 if(!key) {
1011 log_err("out of memory, PORT_ArenaZNew failed");
1012 PORT_FreeArena(arena, PR_FALSE);
1013 return NULL;
1014 }
1015 key->arena = arena;
1016 key->keyType = ktype;
1017 key->pkcs11Slot = NULL;
1018 key->pkcs11ID = CK_INVALID_HANDLE;
1019 return key;
1020 }
1021
nss_buf2ecdsa(unsigned char * key,size_t len,int algo)1022 static SECKEYPublicKey* nss_buf2ecdsa(unsigned char* key, size_t len, int algo)
1023 {
1024 SECKEYPublicKey* pk;
1025 SECItem pub = {siBuffer, NULL, 0};
1026 SECItem params = {siBuffer, NULL, 0};
1027 static unsigned char param256[] = {
1028 /* OBJECTIDENTIFIER 1.2.840.10045.3.1.7 (P-256)
1029 * {iso(1) member-body(2) us(840) ansi-x962(10045) curves(3) prime(1) prime256v1(7)} */
1030 0x06, 0x08, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07
1031 };
1032 static unsigned char param384[] = {
1033 /* OBJECTIDENTIFIER 1.3.132.0.34 (P-384)
1034 * {iso(1) identified-organization(3) certicom(132) curve(0) ansip384r1(34)} */
1035 0x06, 0x05, 0x2b, 0x81, 0x04, 0x00, 0x22
1036 };
1037 unsigned char buf[256+2]; /* sufficient for 2*384/8+1 */
1038
1039 /* check length, which uncompressed must be 2 bignums */
1040 if(algo == LDNS_ECDSAP256SHA256) {
1041 if(len != 2*256/8) return NULL;
1042 /* ECCurve_X9_62_PRIME_256V1 */
1043 } else if(algo == LDNS_ECDSAP384SHA384) {
1044 if(len != 2*384/8) return NULL;
1045 /* ECCurve_X9_62_PRIME_384R1 */
1046 } else return NULL;
1047
1048 buf[0] = 0x04; /* POINT_FORM_UNCOMPRESSED */
1049 memmove(buf+1, key, len);
1050 pub.data = buf;
1051 pub.len = len+1;
1052 if(algo == LDNS_ECDSAP256SHA256) {
1053 params.data = param256;
1054 params.len = sizeof(param256);
1055 } else {
1056 params.data = param384;
1057 params.len = sizeof(param384);
1058 }
1059
1060 pk = nss_key_create(ecKey);
1061 if(!pk)
1062 return NULL;
1063 pk->u.ec.size = (len/2)*8;
1064 if(SECITEM_CopyItem(pk->arena, &pk->u.ec.publicValue, &pub)) {
1065 SECKEY_DestroyPublicKey(pk);
1066 return NULL;
1067 }
1068 if(SECITEM_CopyItem(pk->arena, &pk->u.ec.DEREncodedParams, ¶ms)) {
1069 SECKEY_DestroyPublicKey(pk);
1070 return NULL;
1071 }
1072
1073 return pk;
1074 }
1075
1076 #if defined(USE_DSA) && defined(USE_SHA1)
nss_buf2dsa(unsigned char * key,size_t len)1077 static SECKEYPublicKey* nss_buf2dsa(unsigned char* key, size_t len)
1078 {
1079 SECKEYPublicKey* pk;
1080 uint8_t T;
1081 uint16_t length;
1082 uint16_t offset;
1083 SECItem Q = {siBuffer, NULL, 0};
1084 SECItem P = {siBuffer, NULL, 0};
1085 SECItem G = {siBuffer, NULL, 0};
1086 SECItem Y = {siBuffer, NULL, 0};
1087
1088 if(len == 0)
1089 return NULL;
1090 T = (uint8_t)key[0];
1091 length = (64 + T * 8);
1092 offset = 1;
1093
1094 if (T > 8) {
1095 return NULL;
1096 }
1097 if(len < (size_t)1 + SHA1_LENGTH + 3*length)
1098 return NULL;
1099
1100 Q.data = key+offset;
1101 Q.len = SHA1_LENGTH;
1102 offset += SHA1_LENGTH;
1103
1104 P.data = key+offset;
1105 P.len = length;
1106 offset += length;
1107
1108 G.data = key+offset;
1109 G.len = length;
1110 offset += length;
1111
1112 Y.data = key+offset;
1113 Y.len = length;
1114 offset += length;
1115
1116 pk = nss_key_create(dsaKey);
1117 if(!pk)
1118 return NULL;
1119 if(SECITEM_CopyItem(pk->arena, &pk->u.dsa.params.prime, &P)) {
1120 SECKEY_DestroyPublicKey(pk);
1121 return NULL;
1122 }
1123 if(SECITEM_CopyItem(pk->arena, &pk->u.dsa.params.subPrime, &Q)) {
1124 SECKEY_DestroyPublicKey(pk);
1125 return NULL;
1126 }
1127 if(SECITEM_CopyItem(pk->arena, &pk->u.dsa.params.base, &G)) {
1128 SECKEY_DestroyPublicKey(pk);
1129 return NULL;
1130 }
1131 if(SECITEM_CopyItem(pk->arena, &pk->u.dsa.publicValue, &Y)) {
1132 SECKEY_DestroyPublicKey(pk);
1133 return NULL;
1134 }
1135 return pk;
1136 }
1137 #endif /* USE_DSA && USE_SHA1 */
1138
nss_buf2rsa(unsigned char * key,size_t len)1139 static SECKEYPublicKey* nss_buf2rsa(unsigned char* key, size_t len)
1140 {
1141 SECKEYPublicKey* pk;
1142 uint16_t exp;
1143 uint16_t offset;
1144 uint16_t int16;
1145 SECItem modulus = {siBuffer, NULL, 0};
1146 SECItem exponent = {siBuffer, NULL, 0};
1147 if(len == 0)
1148 return NULL;
1149 if(key[0] == 0) {
1150 if(len < 3)
1151 return NULL;
1152 /* the exponent is too large so it's places further */
1153 memmove(&int16, key+1, 2);
1154 exp = ntohs(int16);
1155 offset = 3;
1156 } else {
1157 exp = key[0];
1158 offset = 1;
1159 }
1160
1161 /* key length at least one */
1162 if(len < (size_t)offset + exp + 1)
1163 return NULL;
1164
1165 exponent.data = key+offset;
1166 exponent.len = exp;
1167 offset += exp;
1168 modulus.data = key+offset;
1169 modulus.len = (len - offset);
1170
1171 pk = nss_key_create(rsaKey);
1172 if(!pk)
1173 return NULL;
1174 if(SECITEM_CopyItem(pk->arena, &pk->u.rsa.modulus, &modulus)) {
1175 SECKEY_DestroyPublicKey(pk);
1176 return NULL;
1177 }
1178 if(SECITEM_CopyItem(pk->arena, &pk->u.rsa.publicExponent, &exponent)) {
1179 SECKEY_DestroyPublicKey(pk);
1180 return NULL;
1181 }
1182 return pk;
1183 }
1184
1185 /**
1186 * Setup key and digest for verification. Adjust sig if necessary.
1187 *
1188 * @param algo: key algorithm
1189 * @param evp_key: EVP PKEY public key to create.
1190 * @param digest_type: digest type to use
1191 * @param key: key to setup for.
1192 * @param keylen: length of key.
1193 * @param prefix: if returned, the ASN prefix for the hashblob.
1194 * @param prefixlen: length of the prefix.
1195 * @return false on failure.
1196 */
1197 static int
nss_setup_key_digest(int algo,SECKEYPublicKey ** pubkey,HASH_HashType * htype,unsigned char * key,size_t keylen,unsigned char ** prefix,size_t * prefixlen)1198 nss_setup_key_digest(int algo, SECKEYPublicKey** pubkey, HASH_HashType* htype,
1199 unsigned char* key, size_t keylen, unsigned char** prefix,
1200 size_t* prefixlen)
1201 {
1202 /* uses libNSS */
1203
1204 /* hash prefix for md5, RFC2537 */
1205 static unsigned char p_md5[] = {0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a,
1206 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04, 0x10};
1207 /* hash prefix to prepend to hash output, from RFC3110 */
1208 static unsigned char p_sha1[] = {0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2B,
1209 0x0E, 0x03, 0x02, 0x1A, 0x05, 0x00, 0x04, 0x14};
1210 /* from RFC5702 */
1211 static unsigned char p_sha256[] = {0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60,
1212 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20};
1213 static unsigned char p_sha512[] = {0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60,
1214 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40};
1215 /* from RFC6234 */
1216 /* for future RSASHA384 ..
1217 static unsigned char p_sha384[] = {0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60,
1218 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00, 0x04, 0x30};
1219 */
1220
1221 switch(algo) {
1222
1223 #if defined(USE_SHA1) || defined(USE_SHA2)
1224 #if defined(USE_DSA) && defined(USE_SHA1)
1225 case LDNS_DSA:
1226 case LDNS_DSA_NSEC3:
1227 *pubkey = nss_buf2dsa(key, keylen);
1228 if(!*pubkey) {
1229 log_err("verify: malloc failure in crypto");
1230 return 0;
1231 }
1232 *htype = HASH_AlgSHA1;
1233 /* no prefix for DSA verification */
1234 break;
1235 #endif
1236 #ifdef USE_SHA1
1237 case LDNS_RSASHA1:
1238 case LDNS_RSASHA1_NSEC3:
1239 #endif
1240 #ifdef USE_SHA2
1241 case LDNS_RSASHA256:
1242 #endif
1243 #ifdef USE_SHA2
1244 case LDNS_RSASHA512:
1245 #endif
1246 *pubkey = nss_buf2rsa(key, keylen);
1247 if(!*pubkey) {
1248 log_err("verify: malloc failure in crypto");
1249 return 0;
1250 }
1251 /* select SHA version */
1252 #ifdef USE_SHA2
1253 if(algo == LDNS_RSASHA256) {
1254 *htype = HASH_AlgSHA256;
1255 *prefix = p_sha256;
1256 *prefixlen = sizeof(p_sha256);
1257 } else
1258 #endif
1259 #ifdef USE_SHA2
1260 if(algo == LDNS_RSASHA512) {
1261 *htype = HASH_AlgSHA512;
1262 *prefix = p_sha512;
1263 *prefixlen = sizeof(p_sha512);
1264 } else
1265 #endif
1266 #ifdef USE_SHA1
1267 {
1268 *htype = HASH_AlgSHA1;
1269 *prefix = p_sha1;
1270 *prefixlen = sizeof(p_sha1);
1271 }
1272 #else
1273 {
1274 verbose(VERB_QUERY, "verify: no digest algo");
1275 return 0;
1276 }
1277 #endif
1278
1279 break;
1280 #endif /* SHA1 or SHA2 */
1281
1282 case LDNS_RSAMD5:
1283 *pubkey = nss_buf2rsa(key, keylen);
1284 if(!*pubkey) {
1285 log_err("verify: malloc failure in crypto");
1286 return 0;
1287 }
1288 *htype = HASH_AlgMD5;
1289 *prefix = p_md5;
1290 *prefixlen = sizeof(p_md5);
1291
1292 break;
1293 #ifdef USE_ECDSA
1294 case LDNS_ECDSAP256SHA256:
1295 *pubkey = nss_buf2ecdsa(key, keylen,
1296 LDNS_ECDSAP256SHA256);
1297 if(!*pubkey) {
1298 log_err("verify: malloc failure in crypto");
1299 return 0;
1300 }
1301 *htype = HASH_AlgSHA256;
1302 /* no prefix for DSA verification */
1303 break;
1304 case LDNS_ECDSAP384SHA384:
1305 *pubkey = nss_buf2ecdsa(key, keylen,
1306 LDNS_ECDSAP384SHA384);
1307 if(!*pubkey) {
1308 log_err("verify: malloc failure in crypto");
1309 return 0;
1310 }
1311 *htype = HASH_AlgSHA384;
1312 /* no prefix for DSA verification */
1313 break;
1314 #endif /* USE_ECDSA */
1315 case LDNS_ECC_GOST:
1316 default:
1317 verbose(VERB_QUERY, "verify: unknown algorithm %d",
1318 algo);
1319 return 0;
1320 }
1321 return 1;
1322 }
1323
1324 /**
1325 * Check a canonical sig+rrset and signature against a dnskey
1326 * @param buf: buffer with data to verify, the first rrsig part and the
1327 * canonicalized rrset.
1328 * @param algo: DNSKEY algorithm.
1329 * @param sigblock: signature rdata field from RRSIG
1330 * @param sigblock_len: length of sigblock data.
1331 * @param key: public key data from DNSKEY RR.
1332 * @param keylen: length of keydata.
1333 * @param reason: bogus reason in more detail.
1334 * @return secure if verification succeeded, bogus on crypto failure,
1335 * unchecked on format errors and alloc failures.
1336 */
1337 enum sec_status
verify_canonrrset(sldns_buffer * buf,int algo,unsigned char * sigblock,unsigned int sigblock_len,unsigned char * key,unsigned int keylen,char ** reason)1338 verify_canonrrset(sldns_buffer* buf, int algo, unsigned char* sigblock,
1339 unsigned int sigblock_len, unsigned char* key, unsigned int keylen,
1340 char** reason)
1341 {
1342 /* uses libNSS */
1343 /* large enough for the different hashes */
1344 unsigned char hash[HASH_LENGTH_MAX];
1345 unsigned char hash2[HASH_LENGTH_MAX*2];
1346 HASH_HashType htype = 0;
1347 SECKEYPublicKey* pubkey = NULL;
1348 SECItem secsig = {siBuffer, sigblock, sigblock_len};
1349 SECItem sechash = {siBuffer, hash, 0};
1350 SECStatus res;
1351 unsigned char* prefix = NULL; /* prefix for hash, RFC3110, RFC5702 */
1352 size_t prefixlen = 0;
1353 int err;
1354
1355 if(!nss_setup_key_digest(algo, &pubkey, &htype, key, keylen,
1356 &prefix, &prefixlen)) {
1357 verbose(VERB_QUERY, "verify: failed to setup key");
1358 *reason = "use of key for crypto failed";
1359 SECKEY_DestroyPublicKey(pubkey);
1360 return sec_status_bogus;
1361 }
1362
1363 #if defined(USE_DSA) && defined(USE_SHA1)
1364 /* need to convert DSA, ECDSA signatures? */
1365 if((algo == LDNS_DSA || algo == LDNS_DSA_NSEC3)) {
1366 if(sigblock_len == 1+2*SHA1_LENGTH) {
1367 secsig.data ++;
1368 secsig.len --;
1369 } else {
1370 SECItem* p = DSAU_DecodeDerSig(&secsig);
1371 if(!p) {
1372 verbose(VERB_QUERY, "verify: failed DER decode");
1373 *reason = "signature DER decode failed";
1374 SECKEY_DestroyPublicKey(pubkey);
1375 return sec_status_bogus;
1376 }
1377 if(SECITEM_CopyItem(pubkey->arena, &secsig, p)) {
1378 log_err("alloc failure in DER decode");
1379 SECKEY_DestroyPublicKey(pubkey);
1380 SECITEM_FreeItem(p, PR_TRUE);
1381 return sec_status_unchecked;
1382 }
1383 SECITEM_FreeItem(p, PR_TRUE);
1384 }
1385 }
1386 #endif /* USE_DSA */
1387
1388 /* do the signature cryptography work */
1389 /* hash the data */
1390 sechash.len = HASH_ResultLen(htype);
1391 if(sechash.len > sizeof(hash)) {
1392 verbose(VERB_QUERY, "verify: hash too large for buffer");
1393 SECKEY_DestroyPublicKey(pubkey);
1394 return sec_status_unchecked;
1395 }
1396 if(HASH_HashBuf(htype, hash, (unsigned char*)sldns_buffer_begin(buf),
1397 (unsigned int)sldns_buffer_limit(buf)) != SECSuccess) {
1398 verbose(VERB_QUERY, "verify: HASH_HashBuf failed");
1399 SECKEY_DestroyPublicKey(pubkey);
1400 return sec_status_unchecked;
1401 }
1402 if(prefix) {
1403 int hashlen = sechash.len;
1404 if(prefixlen+hashlen > sizeof(hash2)) {
1405 verbose(VERB_QUERY, "verify: hashprefix too large");
1406 SECKEY_DestroyPublicKey(pubkey);
1407 return sec_status_unchecked;
1408 }
1409 sechash.data = hash2;
1410 sechash.len = prefixlen+hashlen;
1411 memcpy(sechash.data, prefix, prefixlen);
1412 memmove(sechash.data+prefixlen, hash, hashlen);
1413 }
1414
1415 /* verify the signature */
1416 res = PK11_Verify(pubkey, &secsig, &sechash, NULL /*wincx*/);
1417 SECKEY_DestroyPublicKey(pubkey);
1418
1419 if(res == SECSuccess) {
1420 return sec_status_secure;
1421 }
1422 err = PORT_GetError();
1423 if(err != SEC_ERROR_BAD_SIGNATURE) {
1424 /* failed to verify */
1425 verbose(VERB_QUERY, "verify: PK11_Verify failed: %s",
1426 PORT_ErrorToString(err));
1427 /* if it is not supported, like ECC is removed, we get,
1428 * SEC_ERROR_NO_MODULE */
1429 if(err == SEC_ERROR_NO_MODULE)
1430 return sec_status_unchecked;
1431 /* but other errors are commonly returned
1432 * for a bad signature from NSS. Thus we return bogus,
1433 * not unchecked */
1434 *reason = "signature crypto failed";
1435 return sec_status_bogus;
1436 }
1437 verbose(VERB_QUERY, "verify: signature mismatch: %s",
1438 PORT_ErrorToString(err));
1439 *reason = "signature crypto failed";
1440 return sec_status_bogus;
1441 }
1442
1443 #elif defined(HAVE_NETTLE)
1444
1445 #include "sha.h"
1446 #include "bignum.h"
1447 #include "macros.h"
1448 #include "rsa.h"
1449 #include "dsa.h"
1450 #ifdef HAVE_NETTLE_DSA_COMPAT_H
1451 #include "dsa-compat.h"
1452 #endif
1453 #include "asn1.h"
1454 #ifdef USE_ECDSA
1455 #include "ecdsa.h"
1456 #include "ecc-curve.h"
1457 #endif
1458 #ifdef HAVE_NETTLE_EDDSA_H
1459 #include "eddsa.h"
1460 #endif
1461
1462 static int
_digest_nettle(int algo,uint8_t * buf,size_t len,unsigned char * res)1463 _digest_nettle(int algo, uint8_t* buf, size_t len,
1464 unsigned char* res)
1465 {
1466 switch(algo) {
1467 case SHA1_DIGEST_SIZE:
1468 {
1469 struct sha1_ctx ctx;
1470 sha1_init(&ctx);
1471 sha1_update(&ctx, len, buf);
1472 sha1_digest(&ctx, SHA1_DIGEST_SIZE, res);
1473 return 1;
1474 }
1475 case SHA256_DIGEST_SIZE:
1476 {
1477 struct sha256_ctx ctx;
1478 sha256_init(&ctx);
1479 sha256_update(&ctx, len, buf);
1480 sha256_digest(&ctx, SHA256_DIGEST_SIZE, res);
1481 return 1;
1482 }
1483 case SHA384_DIGEST_SIZE:
1484 {
1485 struct sha384_ctx ctx;
1486 sha384_init(&ctx);
1487 sha384_update(&ctx, len, buf);
1488 sha384_digest(&ctx, SHA384_DIGEST_SIZE, res);
1489 return 1;
1490 }
1491 case SHA512_DIGEST_SIZE:
1492 {
1493 struct sha512_ctx ctx;
1494 sha512_init(&ctx);
1495 sha512_update(&ctx, len, buf);
1496 sha512_digest(&ctx, SHA512_DIGEST_SIZE, res);
1497 return 1;
1498 }
1499 default:
1500 break;
1501 }
1502 return 0;
1503 }
1504
1505 /* return size of digest if supported, or 0 otherwise */
1506 size_t
nsec3_hash_algo_size_supported(int id)1507 nsec3_hash_algo_size_supported(int id)
1508 {
1509 switch(id) {
1510 case NSEC3_HASH_SHA1:
1511 return SHA1_DIGEST_SIZE;
1512 default:
1513 return 0;
1514 }
1515 }
1516
1517 /* perform nsec3 hash. return false on failure */
1518 int
secalgo_nsec3_hash(int algo,unsigned char * buf,size_t len,unsigned char * res)1519 secalgo_nsec3_hash(int algo, unsigned char* buf, size_t len,
1520 unsigned char* res)
1521 {
1522 switch(algo) {
1523 case NSEC3_HASH_SHA1:
1524 return _digest_nettle(SHA1_DIGEST_SIZE, (uint8_t*)buf, len,
1525 res);
1526 default:
1527 return 0;
1528 }
1529 }
1530
1531 void
secalgo_hash_sha256(unsigned char * buf,size_t len,unsigned char * res)1532 secalgo_hash_sha256(unsigned char* buf, size_t len, unsigned char* res)
1533 {
1534 _digest_nettle(SHA256_DIGEST_SIZE, (uint8_t*)buf, len, res);
1535 }
1536
1537 /** secalgo hash structure */
1538 struct secalgo_hash {
1539 /** if it is 384 or 512 */
1540 int active;
1541 /** context for sha384 */
1542 struct sha384_ctx ctx384;
1543 /** context for sha512 */
1544 struct sha512_ctx ctx512;
1545 };
1546
secalgo_hash_create_sha384(void)1547 struct secalgo_hash* secalgo_hash_create_sha384(void)
1548 {
1549 struct secalgo_hash* h = calloc(1, sizeof(*h));
1550 if(!h)
1551 return NULL;
1552 h->active = 384;
1553 sha384_init(&h->ctx384);
1554 return h;
1555 }
1556
secalgo_hash_create_sha512(void)1557 struct secalgo_hash* secalgo_hash_create_sha512(void)
1558 {
1559 struct secalgo_hash* h = calloc(1, sizeof(*h));
1560 if(!h)
1561 return NULL;
1562 h->active = 512;
1563 sha512_init(&h->ctx512);
1564 return h;
1565 }
1566
secalgo_hash_update(struct secalgo_hash * hash,uint8_t * data,size_t len)1567 int secalgo_hash_update(struct secalgo_hash* hash, uint8_t* data, size_t len)
1568 {
1569 if(hash->active == 384) {
1570 sha384_update(&hash->ctx384, len, data);
1571 } else if(hash->active == 512) {
1572 sha512_update(&hash->ctx512, len, data);
1573 } else {
1574 return 0;
1575 }
1576 return 1;
1577 }
1578
secalgo_hash_final(struct secalgo_hash * hash,uint8_t * result,size_t maxlen,size_t * resultlen)1579 int secalgo_hash_final(struct secalgo_hash* hash, uint8_t* result,
1580 size_t maxlen, size_t* resultlen)
1581 {
1582 if(hash->active == 384) {
1583 if(SHA384_DIGEST_SIZE > maxlen) {
1584 *resultlen = 0;
1585 log_err("secalgo_hash_final: hash buffer too small");
1586 return 0;
1587 }
1588 *resultlen = SHA384_DIGEST_SIZE;
1589 sha384_digest(&hash->ctx384, SHA384_DIGEST_SIZE,
1590 (unsigned char*)result);
1591 } else if(hash->active == 512) {
1592 if(SHA512_DIGEST_SIZE > maxlen) {
1593 *resultlen = 0;
1594 log_err("secalgo_hash_final: hash buffer too small");
1595 return 0;
1596 }
1597 *resultlen = SHA512_DIGEST_SIZE;
1598 sha512_digest(&hash->ctx512, SHA512_DIGEST_SIZE,
1599 (unsigned char*)result);
1600 } else {
1601 *resultlen = 0;
1602 return 0;
1603 }
1604 return 1;
1605 }
1606
secalgo_hash_delete(struct secalgo_hash * hash)1607 void secalgo_hash_delete(struct secalgo_hash* hash)
1608 {
1609 if(!hash) return;
1610 free(hash);
1611 }
1612
1613 /**
1614 * Return size of DS digest according to its hash algorithm.
1615 * @param algo: DS digest algo.
1616 * @return size in bytes of digest, or 0 if not supported.
1617 */
1618 size_t
ds_digest_size_supported(int algo)1619 ds_digest_size_supported(int algo)
1620 {
1621 switch(algo) {
1622 case LDNS_SHA1:
1623 #ifdef USE_SHA1
1624 return SHA1_DIGEST_SIZE;
1625 #else
1626 if(fake_sha1) return 20;
1627 return 0;
1628 #endif
1629 #ifdef USE_SHA2
1630 case LDNS_SHA256:
1631 return SHA256_DIGEST_SIZE;
1632 #endif
1633 #ifdef USE_ECDSA
1634 case LDNS_SHA384:
1635 return SHA384_DIGEST_SIZE;
1636 #endif
1637 /* GOST not supported */
1638 case LDNS_HASH_GOST:
1639 default:
1640 break;
1641 }
1642 return 0;
1643 }
1644
1645 int
secalgo_ds_digest(int algo,unsigned char * buf,size_t len,unsigned char * res)1646 secalgo_ds_digest(int algo, unsigned char* buf, size_t len,
1647 unsigned char* res)
1648 {
1649 switch(algo) {
1650 #ifdef USE_SHA1
1651 case LDNS_SHA1:
1652 return _digest_nettle(SHA1_DIGEST_SIZE, buf, len, res);
1653 #endif
1654 #if defined(USE_SHA2)
1655 case LDNS_SHA256:
1656 return _digest_nettle(SHA256_DIGEST_SIZE, buf, len, res);
1657 #endif
1658 #ifdef USE_ECDSA
1659 case LDNS_SHA384:
1660 return _digest_nettle(SHA384_DIGEST_SIZE, buf, len, res);
1661
1662 #endif
1663 case LDNS_HASH_GOST:
1664 default:
1665 verbose(VERB_QUERY, "unknown DS digest algorithm %d",
1666 algo);
1667 break;
1668 }
1669 return 0;
1670 }
1671
1672 int
dnskey_algo_id_is_supported(int id)1673 dnskey_algo_id_is_supported(int id)
1674 {
1675 /* uses libnettle */
1676 switch(id) {
1677 case LDNS_DSA:
1678 case LDNS_DSA_NSEC3:
1679 #if defined(USE_DSA) && defined(USE_SHA1)
1680 return 1;
1681 #else
1682 if(fake_dsa || fake_sha1) return 1;
1683 return 0;
1684 #endif
1685 case LDNS_RSASHA1:
1686 case LDNS_RSASHA1_NSEC3:
1687 #ifdef USE_SHA1
1688 return 1;
1689 #else
1690 if(fake_sha1) return 1;
1691 return 0;
1692 #endif
1693 #ifdef USE_SHA2
1694 case LDNS_RSASHA256:
1695 case LDNS_RSASHA512:
1696 #endif
1697 #ifdef USE_ECDSA
1698 case LDNS_ECDSAP256SHA256:
1699 case LDNS_ECDSAP384SHA384:
1700 #endif
1701 return 1;
1702 #ifdef USE_ED25519
1703 case LDNS_ED25519:
1704 return 1;
1705 #endif
1706 case LDNS_RSAMD5: /* RFC 6725 deprecates RSAMD5 */
1707 case LDNS_ECC_GOST:
1708 default:
1709 return 0;
1710 }
1711 }
1712
1713 #if defined(USE_DSA) && defined(USE_SHA1)
1714 static char *
_verify_nettle_dsa(sldns_buffer * buf,unsigned char * sigblock,unsigned int sigblock_len,unsigned char * key,unsigned int keylen)1715 _verify_nettle_dsa(sldns_buffer* buf, unsigned char* sigblock,
1716 unsigned int sigblock_len, unsigned char* key, unsigned int keylen)
1717 {
1718 uint8_t digest[SHA1_DIGEST_SIZE];
1719 uint8_t key_t_value;
1720 int res = 0;
1721 size_t offset;
1722 struct dsa_public_key pubkey;
1723 struct dsa_signature signature;
1724 unsigned int expected_len;
1725
1726 /* Extract DSA signature from the record */
1727 nettle_dsa_signature_init(&signature);
1728 /* Signature length: 41 bytes - RFC 2536 sec. 3 */
1729 if(sigblock_len == 41) {
1730 if(key[0] != sigblock[0])
1731 return "invalid T value in DSA signature or pubkey";
1732 nettle_mpz_set_str_256_u(signature.r, 20, sigblock+1);
1733 nettle_mpz_set_str_256_u(signature.s, 20, sigblock+1+20);
1734 } else {
1735 /* DER encoded, decode the ASN1 notated R and S bignums */
1736 /* SEQUENCE { r INTEGER, s INTEGER } */
1737 struct asn1_der_iterator i, seq;
1738 if(asn1_der_iterator_first(&i, sigblock_len,
1739 (uint8_t*)sigblock) != ASN1_ITERATOR_CONSTRUCTED
1740 || i.type != ASN1_SEQUENCE)
1741 return "malformed DER encoded DSA signature";
1742 /* decode this element of i using the seq iterator */
1743 if(asn1_der_decode_constructed(&i, &seq) !=
1744 ASN1_ITERATOR_PRIMITIVE || seq.type != ASN1_INTEGER)
1745 return "malformed DER encoded DSA signature";
1746 if(!asn1_der_get_bignum(&seq, signature.r, 20*8))
1747 return "malformed DER encoded DSA signature";
1748 if(asn1_der_iterator_next(&seq) != ASN1_ITERATOR_PRIMITIVE
1749 || seq.type != ASN1_INTEGER)
1750 return "malformed DER encoded DSA signature";
1751 if(!asn1_der_get_bignum(&seq, signature.s, 20*8))
1752 return "malformed DER encoded DSA signature";
1753 if(asn1_der_iterator_next(&i) != ASN1_ITERATOR_END)
1754 return "malformed DER encoded DSA signature";
1755 }
1756
1757 /* Validate T values constraints - RFC 2536 sec. 2 & sec. 3 */
1758 key_t_value = key[0];
1759 if (key_t_value > 8) {
1760 return "invalid T value in DSA pubkey";
1761 }
1762
1763 /* Pubkey minimum length: 21 bytes - RFC 2536 sec. 2 */
1764 if (keylen < 21) {
1765 return "DSA pubkey too short";
1766 }
1767
1768 expected_len = 1 + /* T */
1769 20 + /* Q */
1770 (64 + key_t_value*8) + /* P */
1771 (64 + key_t_value*8) + /* G */
1772 (64 + key_t_value*8); /* Y */
1773 if (keylen != expected_len ) {
1774 return "invalid DSA pubkey length";
1775 }
1776
1777 /* Extract DSA pubkey from the record */
1778 nettle_dsa_public_key_init(&pubkey);
1779 offset = 1;
1780 nettle_mpz_set_str_256_u(pubkey.q, 20, key+offset);
1781 offset += 20;
1782 nettle_mpz_set_str_256_u(pubkey.p, (64 + key_t_value*8), key+offset);
1783 offset += (64 + key_t_value*8);
1784 nettle_mpz_set_str_256_u(pubkey.g, (64 + key_t_value*8), key+offset);
1785 offset += (64 + key_t_value*8);
1786 nettle_mpz_set_str_256_u(pubkey.y, (64 + key_t_value*8), key+offset);
1787
1788 /* Digest content of "buf" and verify its DSA signature in "sigblock"*/
1789 res = _digest_nettle(SHA1_DIGEST_SIZE, (unsigned char*)sldns_buffer_begin(buf),
1790 (unsigned int)sldns_buffer_limit(buf), (unsigned char*)digest);
1791 res &= dsa_sha1_verify_digest(&pubkey, digest, &signature);
1792
1793 /* Clear and return */
1794 nettle_dsa_signature_clear(&signature);
1795 nettle_dsa_public_key_clear(&pubkey);
1796 if (!res)
1797 return "DSA signature verification failed";
1798 else
1799 return NULL;
1800 }
1801 #endif /* USE_DSA */
1802
1803 static char *
_verify_nettle_rsa(sldns_buffer * buf,unsigned int digest_size,char * sigblock,unsigned int sigblock_len,uint8_t * key,unsigned int keylen)1804 _verify_nettle_rsa(sldns_buffer* buf, unsigned int digest_size, char* sigblock,
1805 unsigned int sigblock_len, uint8_t* key, unsigned int keylen)
1806 {
1807 uint16_t exp_len = 0;
1808 size_t exp_offset = 0, mod_offset = 0;
1809 struct rsa_public_key pubkey;
1810 mpz_t signature;
1811 int res = 0;
1812
1813 /* RSA pubkey parsing as per RFC 3110 sec. 2 */
1814 if( keylen <= 1) {
1815 return "null RSA key";
1816 }
1817 if (key[0] != 0) {
1818 /* 1-byte length */
1819 exp_len = key[0];
1820 exp_offset = 1;
1821 } else {
1822 /* 1-byte NUL + 2-bytes exponent length */
1823 if (keylen < 3) {
1824 return "incorrect RSA key length";
1825 }
1826 exp_len = READ_UINT16(key+1);
1827 if (exp_len == 0)
1828 return "null RSA exponent length";
1829 exp_offset = 3;
1830 }
1831 /* Check that we are not over-running input length */
1832 if (keylen < exp_offset + exp_len + 1) {
1833 return "RSA key content shorter than expected";
1834 }
1835 mod_offset = exp_offset + exp_len;
1836 nettle_rsa_public_key_init(&pubkey);
1837 pubkey.size = keylen - mod_offset;
1838 nettle_mpz_set_str_256_u(pubkey.e, exp_len, &key[exp_offset]);
1839 nettle_mpz_set_str_256_u(pubkey.n, pubkey.size, &key[mod_offset]);
1840
1841 /* Digest content of "buf" and verify its RSA signature in "sigblock"*/
1842 nettle_mpz_init_set_str_256_u(signature, sigblock_len, (uint8_t*)sigblock);
1843 switch (digest_size) {
1844 case SHA1_DIGEST_SIZE:
1845 {
1846 uint8_t digest[SHA1_DIGEST_SIZE];
1847 res = _digest_nettle(SHA1_DIGEST_SIZE, (unsigned char*)sldns_buffer_begin(buf),
1848 (unsigned int)sldns_buffer_limit(buf), (unsigned char*)digest);
1849 res &= rsa_sha1_verify_digest(&pubkey, digest, signature);
1850 break;
1851 }
1852 case SHA256_DIGEST_SIZE:
1853 {
1854 uint8_t digest[SHA256_DIGEST_SIZE];
1855 res = _digest_nettle(SHA256_DIGEST_SIZE, (unsigned char*)sldns_buffer_begin(buf),
1856 (unsigned int)sldns_buffer_limit(buf), (unsigned char*)digest);
1857 res &= rsa_sha256_verify_digest(&pubkey, digest, signature);
1858 break;
1859 }
1860 case SHA512_DIGEST_SIZE:
1861 {
1862 uint8_t digest[SHA512_DIGEST_SIZE];
1863 res = _digest_nettle(SHA512_DIGEST_SIZE, (unsigned char*)sldns_buffer_begin(buf),
1864 (unsigned int)sldns_buffer_limit(buf), (unsigned char*)digest);
1865 res &= rsa_sha512_verify_digest(&pubkey, digest, signature);
1866 break;
1867 }
1868 default:
1869 break;
1870 }
1871
1872 /* Clear and return */
1873 nettle_rsa_public_key_clear(&pubkey);
1874 mpz_clear(signature);
1875 if (!res) {
1876 return "RSA signature verification failed";
1877 } else {
1878 return NULL;
1879 }
1880 }
1881
1882 #ifdef USE_ECDSA
1883 static char *
_verify_nettle_ecdsa(sldns_buffer * buf,unsigned int digest_size,unsigned char * sigblock,unsigned int sigblock_len,unsigned char * key,unsigned int keylen)1884 _verify_nettle_ecdsa(sldns_buffer* buf, unsigned int digest_size, unsigned char* sigblock,
1885 unsigned int sigblock_len, unsigned char* key, unsigned int keylen)
1886 {
1887 int res = 0;
1888 struct ecc_point pubkey;
1889 struct dsa_signature signature;
1890
1891 /* Always matched strength, as per RFC 6605 sec. 1 */
1892 if (sigblock_len != 2*digest_size || keylen != 2*digest_size) {
1893 return "wrong ECDSA signature length";
1894 }
1895
1896 /* Parse ECDSA signature as per RFC 6605 sec. 4 */
1897 nettle_dsa_signature_init(&signature);
1898 switch (digest_size) {
1899 case SHA256_DIGEST_SIZE:
1900 {
1901 uint8_t digest[SHA256_DIGEST_SIZE];
1902 mpz_t x, y;
1903 nettle_ecc_point_init(&pubkey, nettle_get_secp_256r1());
1904 nettle_mpz_init_set_str_256_u(x, SHA256_DIGEST_SIZE, key);
1905 nettle_mpz_init_set_str_256_u(y, SHA256_DIGEST_SIZE, key+SHA256_DIGEST_SIZE);
1906 nettle_mpz_set_str_256_u(signature.r, SHA256_DIGEST_SIZE, sigblock);
1907 nettle_mpz_set_str_256_u(signature.s, SHA256_DIGEST_SIZE, sigblock+SHA256_DIGEST_SIZE);
1908 res = _digest_nettle(SHA256_DIGEST_SIZE, (unsigned char*)sldns_buffer_begin(buf),
1909 (unsigned int)sldns_buffer_limit(buf), (unsigned char*)digest);
1910 res &= nettle_ecc_point_set(&pubkey, x, y);
1911 res &= nettle_ecdsa_verify (&pubkey, SHA256_DIGEST_SIZE, digest, &signature);
1912 mpz_clear(x);
1913 mpz_clear(y);
1914 nettle_ecc_point_clear(&pubkey);
1915 break;
1916 }
1917 case SHA384_DIGEST_SIZE:
1918 {
1919 uint8_t digest[SHA384_DIGEST_SIZE];
1920 mpz_t x, y;
1921 nettle_ecc_point_init(&pubkey, nettle_get_secp_384r1());
1922 nettle_mpz_init_set_str_256_u(x, SHA384_DIGEST_SIZE, key);
1923 nettle_mpz_init_set_str_256_u(y, SHA384_DIGEST_SIZE, key+SHA384_DIGEST_SIZE);
1924 nettle_mpz_set_str_256_u(signature.r, SHA384_DIGEST_SIZE, sigblock);
1925 nettle_mpz_set_str_256_u(signature.s, SHA384_DIGEST_SIZE, sigblock+SHA384_DIGEST_SIZE);
1926 res = _digest_nettle(SHA384_DIGEST_SIZE, (unsigned char*)sldns_buffer_begin(buf),
1927 (unsigned int)sldns_buffer_limit(buf), (unsigned char*)digest);
1928 res &= nettle_ecc_point_set(&pubkey, x, y);
1929 res &= nettle_ecdsa_verify (&pubkey, SHA384_DIGEST_SIZE, digest, &signature);
1930 mpz_clear(x);
1931 mpz_clear(y);
1932 nettle_ecc_point_clear(&pubkey);
1933 break;
1934 }
1935 default:
1936 return "unknown ECDSA algorithm";
1937 }
1938
1939 /* Clear and return */
1940 nettle_dsa_signature_clear(&signature);
1941 if (!res)
1942 return "ECDSA signature verification failed";
1943 else
1944 return NULL;
1945 }
1946 #endif
1947
1948 #ifdef USE_ED25519
1949 static char *
_verify_nettle_ed25519(sldns_buffer * buf,unsigned char * sigblock,unsigned int sigblock_len,unsigned char * key,unsigned int keylen)1950 _verify_nettle_ed25519(sldns_buffer* buf, unsigned char* sigblock,
1951 unsigned int sigblock_len, unsigned char* key, unsigned int keylen)
1952 {
1953 int res = 0;
1954
1955 if(sigblock_len != ED25519_SIGNATURE_SIZE) {
1956 return "wrong ED25519 signature length";
1957 }
1958 if(keylen != ED25519_KEY_SIZE) {
1959 return "wrong ED25519 key length";
1960 }
1961
1962 res = ed25519_sha512_verify((uint8_t*)key, sldns_buffer_limit(buf),
1963 sldns_buffer_begin(buf), (uint8_t*)sigblock);
1964
1965 if (!res)
1966 return "ED25519 signature verification failed";
1967 else
1968 return NULL;
1969 }
1970 #endif
1971
1972 /**
1973 * Check a canonical sig+rrset and signature against a dnskey
1974 * @param buf: buffer with data to verify, the first rrsig part and the
1975 * canonicalized rrset.
1976 * @param algo: DNSKEY algorithm.
1977 * @param sigblock: signature rdata field from RRSIG
1978 * @param sigblock_len: length of sigblock data.
1979 * @param key: public key data from DNSKEY RR.
1980 * @param keylen: length of keydata.
1981 * @param reason: bogus reason in more detail.
1982 * @return secure if verification succeeded, bogus on crypto failure,
1983 * unchecked on format errors and alloc failures.
1984 */
1985 enum sec_status
verify_canonrrset(sldns_buffer * buf,int algo,unsigned char * sigblock,unsigned int sigblock_len,unsigned char * key,unsigned int keylen,char ** reason)1986 verify_canonrrset(sldns_buffer* buf, int algo, unsigned char* sigblock,
1987 unsigned int sigblock_len, unsigned char* key, unsigned int keylen,
1988 char** reason)
1989 {
1990 unsigned int digest_size = 0;
1991
1992 if (sigblock_len == 0 || keylen == 0) {
1993 *reason = "null signature";
1994 return sec_status_bogus;
1995 }
1996
1997 #ifndef USE_DSA
1998 if((algo == LDNS_DSA || algo == LDNS_DSA_NSEC3) &&(fake_dsa||fake_sha1))
1999 return sec_status_secure;
2000 #endif
2001 #ifndef USE_SHA1
2002 if(fake_sha1 && (algo == LDNS_DSA || algo == LDNS_DSA_NSEC3 || algo == LDNS_RSASHA1 || algo == LDNS_RSASHA1_NSEC3))
2003 return sec_status_secure;
2004 #endif
2005
2006 switch(algo) {
2007 #if defined(USE_DSA) && defined(USE_SHA1)
2008 case LDNS_DSA:
2009 case LDNS_DSA_NSEC3:
2010 *reason = _verify_nettle_dsa(buf, sigblock, sigblock_len, key, keylen);
2011 if (*reason != NULL)
2012 return sec_status_bogus;
2013 else
2014 return sec_status_secure;
2015 #endif /* USE_DSA */
2016
2017 #ifdef USE_SHA1
2018 case LDNS_RSASHA1:
2019 case LDNS_RSASHA1_NSEC3:
2020 digest_size = (digest_size ? digest_size : SHA1_DIGEST_SIZE);
2021 #endif
2022 /* double fallthrough annotation to please gcc parser */
2023 /* fallthrough */
2024 #ifdef USE_SHA2
2025 /* fallthrough */
2026 case LDNS_RSASHA256:
2027 digest_size = (digest_size ? digest_size : SHA256_DIGEST_SIZE);
2028 /* fallthrough */
2029 case LDNS_RSASHA512:
2030 digest_size = (digest_size ? digest_size : SHA512_DIGEST_SIZE);
2031
2032 #endif
2033 *reason = _verify_nettle_rsa(buf, digest_size, (char*)sigblock,
2034 sigblock_len, key, keylen);
2035 if (*reason != NULL)
2036 return sec_status_bogus;
2037 else
2038 return sec_status_secure;
2039
2040 #ifdef USE_ECDSA
2041 case LDNS_ECDSAP256SHA256:
2042 digest_size = (digest_size ? digest_size : SHA256_DIGEST_SIZE);
2043 /* fallthrough */
2044 case LDNS_ECDSAP384SHA384:
2045 digest_size = (digest_size ? digest_size : SHA384_DIGEST_SIZE);
2046 *reason = _verify_nettle_ecdsa(buf, digest_size, sigblock,
2047 sigblock_len, key, keylen);
2048 if (*reason != NULL)
2049 return sec_status_bogus;
2050 else
2051 return sec_status_secure;
2052 #endif
2053 #ifdef USE_ED25519
2054 case LDNS_ED25519:
2055 *reason = _verify_nettle_ed25519(buf, sigblock, sigblock_len,
2056 key, keylen);
2057 if (*reason != NULL)
2058 return sec_status_bogus;
2059 else
2060 return sec_status_secure;
2061 #endif
2062 case LDNS_RSAMD5:
2063 case LDNS_ECC_GOST:
2064 default:
2065 *reason = "unable to verify signature, unknown algorithm";
2066 return sec_status_bogus;
2067 }
2068 }
2069
2070 #endif /* HAVE_SSL or HAVE_NSS or HAVE_NETTLE */
2071