1 /*
2 * Copyright 2006-2023 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 /*
11 * RSA low level APIs are deprecated for public use, but still ok for
12 * internal use.
13 */
14 #include "internal/deprecated.h"
15
16 #include <stdio.h>
17 #include "internal/cryptlib.h"
18 #include <openssl/asn1t.h>
19 #include <openssl/x509.h>
20 #include <openssl/bn.h>
21 #include <openssl/core_names.h>
22 #include <openssl/param_build.h>
23 #include "crypto/asn1.h"
24 #include "crypto/evp.h"
25 #include "crypto/rsa.h"
26 #include "rsa_local.h"
27
28 /* Set any parameters associated with pkey */
rsa_param_encode(const EVP_PKEY * pkey,ASN1_STRING ** pstr,int * pstrtype)29 static int rsa_param_encode(const EVP_PKEY *pkey,
30 ASN1_STRING **pstr, int *pstrtype)
31 {
32 const RSA *rsa = pkey->pkey.rsa;
33
34 *pstr = NULL;
35 /* If RSA it's just NULL type */
36 if (RSA_test_flags(rsa, RSA_FLAG_TYPE_MASK) != RSA_FLAG_TYPE_RSASSAPSS) {
37 *pstrtype = V_ASN1_NULL;
38 return 1;
39 }
40 /* If no PSS parameters we omit parameters entirely */
41 if (rsa->pss == NULL) {
42 *pstrtype = V_ASN1_UNDEF;
43 return 1;
44 }
45 /* Encode PSS parameters */
46 if (ASN1_item_pack(rsa->pss, ASN1_ITEM_rptr(RSA_PSS_PARAMS), pstr) == NULL)
47 return 0;
48
49 *pstrtype = V_ASN1_SEQUENCE;
50 return 1;
51 }
52 /* Decode any parameters and set them in RSA structure */
rsa_pub_encode(X509_PUBKEY * pk,const EVP_PKEY * pkey)53 static int rsa_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
54 {
55 unsigned char *penc = NULL;
56 int penclen;
57 ASN1_STRING *str;
58 int strtype;
59
60 if (!rsa_param_encode(pkey, &str, &strtype))
61 return 0;
62 penclen = i2d_RSAPublicKey(pkey->pkey.rsa, &penc);
63 if (penclen <= 0) {
64 ASN1_STRING_free(str);
65 return 0;
66 }
67 if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(pkey->ameth->pkey_id),
68 strtype, str, penc, penclen))
69 return 1;
70
71 OPENSSL_free(penc);
72 ASN1_STRING_free(str);
73 return 0;
74 }
75
rsa_pub_decode(EVP_PKEY * pkey,const X509_PUBKEY * pubkey)76 static int rsa_pub_decode(EVP_PKEY *pkey, const X509_PUBKEY *pubkey)
77 {
78 const unsigned char *p;
79 int pklen;
80 X509_ALGOR *alg;
81 RSA *rsa = NULL;
82
83 if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &alg, pubkey))
84 return 0;
85 if ((rsa = d2i_RSAPublicKey(NULL, &p, pklen)) == NULL)
86 return 0;
87 if (!ossl_rsa_param_decode(rsa, alg)) {
88 RSA_free(rsa);
89 return 0;
90 }
91
92 RSA_clear_flags(rsa, RSA_FLAG_TYPE_MASK);
93 switch (pkey->ameth->pkey_id) {
94 case EVP_PKEY_RSA:
95 RSA_set_flags(rsa, RSA_FLAG_TYPE_RSA);
96 break;
97 case EVP_PKEY_RSA_PSS:
98 RSA_set_flags(rsa, RSA_FLAG_TYPE_RSASSAPSS);
99 break;
100 default:
101 /* Leave the type bits zero */
102 break;
103 }
104
105 if (!EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa)) {
106 RSA_free(rsa);
107 return 0;
108 }
109 return 1;
110 }
111
rsa_pub_cmp(const EVP_PKEY * a,const EVP_PKEY * b)112 static int rsa_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
113 {
114 /*
115 * Don't check the public/private key, this is mostly for smart
116 * cards.
117 */
118 if (((RSA_flags(a->pkey.rsa) & RSA_METHOD_FLAG_NO_CHECK))
119 || (RSA_flags(b->pkey.rsa) & RSA_METHOD_FLAG_NO_CHECK)) {
120 return 1;
121 }
122
123 if (BN_cmp(b->pkey.rsa->n, a->pkey.rsa->n) != 0
124 || BN_cmp(b->pkey.rsa->e, a->pkey.rsa->e) != 0)
125 return 0;
126 return 1;
127 }
128
old_rsa_priv_decode(EVP_PKEY * pkey,const unsigned char ** pder,int derlen)129 static int old_rsa_priv_decode(EVP_PKEY *pkey,
130 const unsigned char **pder, int derlen)
131 {
132 RSA *rsa;
133
134 if ((rsa = d2i_RSAPrivateKey(NULL, pder, derlen)) == NULL)
135 return 0;
136 EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa);
137 return 1;
138 }
139
old_rsa_priv_encode(const EVP_PKEY * pkey,unsigned char ** pder)140 static int old_rsa_priv_encode(const EVP_PKEY *pkey, unsigned char **pder)
141 {
142 return i2d_RSAPrivateKey(pkey->pkey.rsa, pder);
143 }
144
rsa_priv_encode(PKCS8_PRIV_KEY_INFO * p8,const EVP_PKEY * pkey)145 static int rsa_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
146 {
147 unsigned char *rk = NULL;
148 int rklen;
149 ASN1_STRING *str;
150 int strtype;
151
152 if (!rsa_param_encode(pkey, &str, &strtype))
153 return 0;
154 rklen = i2d_RSAPrivateKey(pkey->pkey.rsa, &rk);
155
156 if (rklen <= 0) {
157 ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
158 ASN1_STRING_free(str);
159 return 0;
160 }
161
162 if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(pkey->ameth->pkey_id), 0,
163 strtype, str, rk, rklen)) {
164 ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
165 ASN1_STRING_free(str);
166 OPENSSL_clear_free(rk, rklen);
167 return 0;
168 }
169
170 return 1;
171 }
172
rsa_priv_decode(EVP_PKEY * pkey,const PKCS8_PRIV_KEY_INFO * p8)173 static int rsa_priv_decode(EVP_PKEY *pkey, const PKCS8_PRIV_KEY_INFO *p8)
174 {
175 int ret = 0;
176 RSA *rsa = ossl_rsa_key_from_pkcs8(p8, NULL, NULL);
177
178 if (rsa != NULL) {
179 ret = 1;
180 EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa);
181 }
182 return ret;
183 }
184
int_rsa_size(const EVP_PKEY * pkey)185 static int int_rsa_size(const EVP_PKEY *pkey)
186 {
187 return RSA_size(pkey->pkey.rsa);
188 }
189
rsa_bits(const EVP_PKEY * pkey)190 static int rsa_bits(const EVP_PKEY *pkey)
191 {
192 return BN_num_bits(pkey->pkey.rsa->n);
193 }
194
rsa_security_bits(const EVP_PKEY * pkey)195 static int rsa_security_bits(const EVP_PKEY *pkey)
196 {
197 return RSA_security_bits(pkey->pkey.rsa);
198 }
199
int_rsa_free(EVP_PKEY * pkey)200 static void int_rsa_free(EVP_PKEY *pkey)
201 {
202 RSA_free(pkey->pkey.rsa);
203 }
204
rsa_pss_param_print(BIO * bp,int pss_key,RSA_PSS_PARAMS * pss,int indent)205 static int rsa_pss_param_print(BIO *bp, int pss_key, RSA_PSS_PARAMS *pss,
206 int indent)
207 {
208 int rv = 0;
209 X509_ALGOR *maskHash = NULL;
210
211 if (!BIO_indent(bp, indent, 128))
212 goto err;
213 if (pss_key) {
214 if (pss == NULL) {
215 if (BIO_puts(bp, "No PSS parameter restrictions\n") <= 0)
216 return 0;
217 return 1;
218 } else {
219 if (BIO_puts(bp, "PSS parameter restrictions:") <= 0)
220 return 0;
221 }
222 } else if (pss == NULL) {
223 if (BIO_puts(bp,"(INVALID PSS PARAMETERS)\n") <= 0)
224 return 0;
225 return 1;
226 }
227 if (BIO_puts(bp, "\n") <= 0)
228 goto err;
229 if (pss_key)
230 indent += 2;
231 if (!BIO_indent(bp, indent, 128))
232 goto err;
233 if (BIO_puts(bp, "Hash Algorithm: ") <= 0)
234 goto err;
235
236 if (pss->hashAlgorithm) {
237 if (i2a_ASN1_OBJECT(bp, pss->hashAlgorithm->algorithm) <= 0)
238 goto err;
239 } else if (BIO_puts(bp, "sha1 (default)") <= 0) {
240 goto err;
241 }
242
243 if (BIO_puts(bp, "\n") <= 0)
244 goto err;
245
246 if (!BIO_indent(bp, indent, 128))
247 goto err;
248
249 if (BIO_puts(bp, "Mask Algorithm: ") <= 0)
250 goto err;
251 if (pss->maskGenAlgorithm) {
252 if (i2a_ASN1_OBJECT(bp, pss->maskGenAlgorithm->algorithm) <= 0)
253 goto err;
254 if (BIO_puts(bp, " with ") <= 0)
255 goto err;
256 maskHash = ossl_x509_algor_mgf1_decode(pss->maskGenAlgorithm);
257 if (maskHash != NULL) {
258 if (i2a_ASN1_OBJECT(bp, maskHash->algorithm) <= 0)
259 goto err;
260 } else if (BIO_puts(bp, "INVALID") <= 0) {
261 goto err;
262 }
263 } else if (BIO_puts(bp, "mgf1 with sha1 (default)") <= 0) {
264 goto err;
265 }
266 BIO_puts(bp, "\n");
267
268 if (!BIO_indent(bp, indent, 128))
269 goto err;
270 if (BIO_printf(bp, "%s Salt Length: 0x", pss_key ? "Minimum" : "") <= 0)
271 goto err;
272 if (pss->saltLength) {
273 if (i2a_ASN1_INTEGER(bp, pss->saltLength) <= 0)
274 goto err;
275 } else if (BIO_puts(bp, "14 (default)") <= 0) {
276 goto err;
277 }
278 BIO_puts(bp, "\n");
279
280 if (!BIO_indent(bp, indent, 128))
281 goto err;
282 if (BIO_puts(bp, "Trailer Field: 0x") <= 0)
283 goto err;
284 if (pss->trailerField) {
285 if (i2a_ASN1_INTEGER(bp, pss->trailerField) <= 0)
286 goto err;
287 } else if (BIO_puts(bp, "01 (default)") <= 0) {
288 goto err;
289 }
290 BIO_puts(bp, "\n");
291
292 rv = 1;
293
294 err:
295 X509_ALGOR_free(maskHash);
296 return rv;
297
298 }
299
pkey_rsa_print(BIO * bp,const EVP_PKEY * pkey,int off,int priv)300 static int pkey_rsa_print(BIO *bp, const EVP_PKEY *pkey, int off, int priv)
301 {
302 const RSA *x = pkey->pkey.rsa;
303 char *str;
304 const char *s;
305 int ret = 0, mod_len = 0, ex_primes;
306
307 if (x->n != NULL)
308 mod_len = BN_num_bits(x->n);
309 ex_primes = sk_RSA_PRIME_INFO_num(x->prime_infos);
310
311 if (!BIO_indent(bp, off, 128))
312 goto err;
313
314 if (BIO_printf(bp, "%s ", pkey_is_pss(pkey) ? "RSA-PSS" : "RSA") <= 0)
315 goto err;
316
317 if (priv && x->d) {
318 if (BIO_printf(bp, "Private-Key: (%d bit, %d primes)\n",
319 mod_len, ex_primes <= 0 ? 2 : ex_primes + 2) <= 0)
320 goto err;
321 str = "modulus:";
322 s = "publicExponent:";
323 } else {
324 if (BIO_printf(bp, "Public-Key: (%d bit)\n", mod_len) <= 0)
325 goto err;
326 str = "Modulus:";
327 s = "Exponent:";
328 }
329 if (!ASN1_bn_print(bp, str, x->n, NULL, off))
330 goto err;
331 if (!ASN1_bn_print(bp, s, x->e, NULL, off))
332 goto err;
333 if (priv) {
334 int i;
335
336 if (!ASN1_bn_print(bp, "privateExponent:", x->d, NULL, off))
337 goto err;
338 if (!ASN1_bn_print(bp, "prime1:", x->p, NULL, off))
339 goto err;
340 if (!ASN1_bn_print(bp, "prime2:", x->q, NULL, off))
341 goto err;
342 if (!ASN1_bn_print(bp, "exponent1:", x->dmp1, NULL, off))
343 goto err;
344 if (!ASN1_bn_print(bp, "exponent2:", x->dmq1, NULL, off))
345 goto err;
346 if (!ASN1_bn_print(bp, "coefficient:", x->iqmp, NULL, off))
347 goto err;
348 for (i = 0; i < sk_RSA_PRIME_INFO_num(x->prime_infos); i++) {
349 /* print multi-prime info */
350 BIGNUM *bn = NULL;
351 RSA_PRIME_INFO *pinfo;
352 int j;
353
354 pinfo = sk_RSA_PRIME_INFO_value(x->prime_infos, i);
355 for (j = 0; j < 3; j++) {
356 if (!BIO_indent(bp, off, 128))
357 goto err;
358 switch (j) {
359 case 0:
360 if (BIO_printf(bp, "prime%d:", i + 3) <= 0)
361 goto err;
362 bn = pinfo->r;
363 break;
364 case 1:
365 if (BIO_printf(bp, "exponent%d:", i + 3) <= 0)
366 goto err;
367 bn = pinfo->d;
368 break;
369 case 2:
370 if (BIO_printf(bp, "coefficient%d:", i + 3) <= 0)
371 goto err;
372 bn = pinfo->t;
373 break;
374 default:
375 break;
376 }
377 if (!ASN1_bn_print(bp, "", bn, NULL, off))
378 goto err;
379 }
380 }
381 }
382 if (pkey_is_pss(pkey) && !rsa_pss_param_print(bp, 1, x->pss, off))
383 goto err;
384 ret = 1;
385 err:
386 return ret;
387 }
388
rsa_pub_print(BIO * bp,const EVP_PKEY * pkey,int indent,ASN1_PCTX * ctx)389 static int rsa_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent,
390 ASN1_PCTX *ctx)
391 {
392 return pkey_rsa_print(bp, pkey, indent, 0);
393 }
394
rsa_priv_print(BIO * bp,const EVP_PKEY * pkey,int indent,ASN1_PCTX * ctx)395 static int rsa_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent,
396 ASN1_PCTX *ctx)
397 {
398 return pkey_rsa_print(bp, pkey, indent, 1);
399 }
400
rsa_sig_print(BIO * bp,const X509_ALGOR * sigalg,const ASN1_STRING * sig,int indent,ASN1_PCTX * pctx)401 static int rsa_sig_print(BIO *bp, const X509_ALGOR *sigalg,
402 const ASN1_STRING *sig, int indent, ASN1_PCTX *pctx)
403 {
404 if (OBJ_obj2nid(sigalg->algorithm) == EVP_PKEY_RSA_PSS) {
405 int rv;
406 RSA_PSS_PARAMS *pss = ossl_rsa_pss_decode(sigalg);
407
408 rv = rsa_pss_param_print(bp, 0, pss, indent);
409 RSA_PSS_PARAMS_free(pss);
410 if (!rv)
411 return 0;
412 } else if (BIO_puts(bp, "\n") <= 0) {
413 return 0;
414 }
415 if (sig)
416 return X509_signature_dump(bp, sig, indent);
417 return 1;
418 }
419
rsa_pkey_ctrl(EVP_PKEY * pkey,int op,long arg1,void * arg2)420 static int rsa_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
421 {
422 const EVP_MD *md;
423 const EVP_MD *mgf1md;
424 int min_saltlen;
425
426 switch (op) {
427 case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
428 if (pkey->pkey.rsa->pss != NULL) {
429 if (!ossl_rsa_pss_get_param(pkey->pkey.rsa->pss, &md, &mgf1md,
430 &min_saltlen)) {
431 ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR);
432 return 0;
433 }
434 *(int *)arg2 = EVP_MD_get_type(md);
435 /* Return of 2 indicates this MD is mandatory */
436 return 2;
437 }
438 *(int *)arg2 = NID_sha256;
439 return 1;
440
441 default:
442 return -2;
443 }
444 }
445
446 /*
447 * Convert EVP_PKEY_CTX in PSS mode into corresponding algorithm parameter,
448 * suitable for setting an AlgorithmIdentifier.
449 */
450
rsa_ctx_to_pss(EVP_PKEY_CTX * pkctx)451 static RSA_PSS_PARAMS *rsa_ctx_to_pss(EVP_PKEY_CTX *pkctx)
452 {
453 const EVP_MD *sigmd, *mgf1md;
454 EVP_PKEY *pk = EVP_PKEY_CTX_get0_pkey(pkctx);
455 int saltlen;
456
457 if (EVP_PKEY_CTX_get_signature_md(pkctx, &sigmd) <= 0)
458 return NULL;
459 if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
460 return NULL;
461 if (EVP_PKEY_CTX_get_rsa_pss_saltlen(pkctx, &saltlen) <= 0)
462 return NULL;
463 if (saltlen == -1) {
464 saltlen = EVP_MD_get_size(sigmd);
465 } else if (saltlen == -2 || saltlen == -3) {
466 saltlen = EVP_PKEY_get_size(pk) - EVP_MD_get_size(sigmd) - 2;
467 if ((EVP_PKEY_get_bits(pk) & 0x7) == 1)
468 saltlen--;
469 if (saltlen < 0)
470 return NULL;
471 }
472
473 return ossl_rsa_pss_params_create(sigmd, mgf1md, saltlen);
474 }
475
ossl_rsa_pss_params_create(const EVP_MD * sigmd,const EVP_MD * mgf1md,int saltlen)476 RSA_PSS_PARAMS *ossl_rsa_pss_params_create(const EVP_MD *sigmd,
477 const EVP_MD *mgf1md, int saltlen)
478 {
479 RSA_PSS_PARAMS *pss = RSA_PSS_PARAMS_new();
480
481 if (pss == NULL)
482 goto err;
483 if (saltlen != 20) {
484 pss->saltLength = ASN1_INTEGER_new();
485 if (pss->saltLength == NULL)
486 goto err;
487 if (!ASN1_INTEGER_set(pss->saltLength, saltlen))
488 goto err;
489 }
490 if (!ossl_x509_algor_new_from_md(&pss->hashAlgorithm, sigmd))
491 goto err;
492 if (mgf1md == NULL)
493 mgf1md = sigmd;
494 if (!ossl_x509_algor_md_to_mgf1(&pss->maskGenAlgorithm, mgf1md))
495 goto err;
496 if (!ossl_x509_algor_new_from_md(&pss->maskHash, mgf1md))
497 goto err;
498 return pss;
499 err:
500 RSA_PSS_PARAMS_free(pss);
501 return NULL;
502 }
503
ossl_rsa_ctx_to_pss_string(EVP_PKEY_CTX * pkctx)504 ASN1_STRING *ossl_rsa_ctx_to_pss_string(EVP_PKEY_CTX *pkctx)
505 {
506 RSA_PSS_PARAMS *pss = rsa_ctx_to_pss(pkctx);
507 ASN1_STRING *os;
508
509 if (pss == NULL)
510 return NULL;
511
512 os = ASN1_item_pack(pss, ASN1_ITEM_rptr(RSA_PSS_PARAMS), NULL);
513 RSA_PSS_PARAMS_free(pss);
514 return os;
515 }
516
517 /*
518 * From PSS AlgorithmIdentifier set public key parameters. If pkey isn't NULL
519 * then the EVP_MD_CTX is setup and initialised. If it is NULL parameters are
520 * passed to pkctx instead.
521 */
522
ossl_rsa_pss_to_ctx(EVP_MD_CTX * ctx,EVP_PKEY_CTX * pkctx,const X509_ALGOR * sigalg,EVP_PKEY * pkey)523 int ossl_rsa_pss_to_ctx(EVP_MD_CTX *ctx, EVP_PKEY_CTX *pkctx,
524 const X509_ALGOR *sigalg, EVP_PKEY *pkey)
525 {
526 int rv = -1;
527 int saltlen;
528 const EVP_MD *mgf1md = NULL, *md = NULL;
529 RSA_PSS_PARAMS *pss;
530
531 /* Sanity check: make sure it is PSS */
532 if (OBJ_obj2nid(sigalg->algorithm) != EVP_PKEY_RSA_PSS) {
533 ERR_raise(ERR_LIB_RSA, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
534 return -1;
535 }
536 /* Decode PSS parameters */
537 pss = ossl_rsa_pss_decode(sigalg);
538
539 if (!ossl_rsa_pss_get_param(pss, &md, &mgf1md, &saltlen)) {
540 ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PSS_PARAMETERS);
541 goto err;
542 }
543
544 /* We have all parameters now set up context */
545 if (pkey) {
546 if (!EVP_DigestVerifyInit(ctx, &pkctx, md, NULL, pkey))
547 goto err;
548 } else {
549 const EVP_MD *checkmd;
550 if (EVP_PKEY_CTX_get_signature_md(pkctx, &checkmd) <= 0)
551 goto err;
552 if (EVP_MD_get_type(md) != EVP_MD_get_type(checkmd)) {
553 ERR_raise(ERR_LIB_RSA, RSA_R_DIGEST_DOES_NOT_MATCH);
554 goto err;
555 }
556 }
557
558 if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_PSS_PADDING) <= 0)
559 goto err;
560
561 if (EVP_PKEY_CTX_set_rsa_pss_saltlen(pkctx, saltlen) <= 0)
562 goto err;
563
564 if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
565 goto err;
566 /* Carry on */
567 rv = 1;
568
569 err:
570 RSA_PSS_PARAMS_free(pss);
571 return rv;
572 }
573
rsa_pss_verify_param(const EVP_MD ** pmd,const EVP_MD ** pmgf1md,int * psaltlen,int * ptrailerField)574 static int rsa_pss_verify_param(const EVP_MD **pmd, const EVP_MD **pmgf1md,
575 int *psaltlen, int *ptrailerField)
576 {
577 if (psaltlen != NULL && *psaltlen < 0) {
578 ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_SALT_LENGTH);
579 return 0;
580 }
581 /*
582 * low-level routines support only trailer field 0xbc (value 1) and
583 * PKCS#1 says we should reject any other value anyway.
584 */
585 if (ptrailerField != NULL && *ptrailerField != 1) {
586 ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_TRAILER);
587 return 0;
588 }
589 return 1;
590 }
591
ossl_rsa_pss_get_param(const RSA_PSS_PARAMS * pss,const EVP_MD ** pmd,const EVP_MD ** pmgf1md,int * psaltlen)592 int ossl_rsa_pss_get_param(const RSA_PSS_PARAMS *pss, const EVP_MD **pmd,
593 const EVP_MD **pmgf1md, int *psaltlen)
594 {
595 /*
596 * Callers do not care about the trailer field, and yet, we must
597 * pass it from get_param to verify_param, since the latter checks
598 * its value.
599 *
600 * When callers start caring, it's a simple thing to add another
601 * argument to this function.
602 */
603 int trailerField = 0;
604
605 return ossl_rsa_pss_get_param_unverified(pss, pmd, pmgf1md, psaltlen,
606 &trailerField)
607 && rsa_pss_verify_param(pmd, pmgf1md, psaltlen, &trailerField);
608 }
609
610 /*
611 * Customised RSA item verification routine. This is called when a signature
612 * is encountered requiring special handling. We currently only handle PSS.
613 */
614
rsa_item_verify(EVP_MD_CTX * ctx,const ASN1_ITEM * it,const void * asn,const X509_ALGOR * sigalg,const ASN1_BIT_STRING * sig,EVP_PKEY * pkey)615 static int rsa_item_verify(EVP_MD_CTX *ctx, const ASN1_ITEM *it,
616 const void *asn, const X509_ALGOR *sigalg,
617 const ASN1_BIT_STRING *sig, EVP_PKEY *pkey)
618 {
619 /* Sanity check: make sure it is PSS */
620 if (OBJ_obj2nid(sigalg->algorithm) != EVP_PKEY_RSA_PSS) {
621 ERR_raise(ERR_LIB_RSA, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
622 return -1;
623 }
624 if (ossl_rsa_pss_to_ctx(ctx, NULL, sigalg, pkey) > 0) {
625 /* Carry on */
626 return 2;
627 }
628 return -1;
629 }
630
rsa_item_sign(EVP_MD_CTX * ctx,const ASN1_ITEM * it,const void * asn,X509_ALGOR * alg1,X509_ALGOR * alg2,ASN1_BIT_STRING * sig)631 static int rsa_item_sign(EVP_MD_CTX *ctx, const ASN1_ITEM *it, const void *asn,
632 X509_ALGOR *alg1, X509_ALGOR *alg2,
633 ASN1_BIT_STRING *sig)
634 {
635 int pad_mode;
636 EVP_PKEY_CTX *pkctx = EVP_MD_CTX_get_pkey_ctx(ctx);
637
638 if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
639 return 0;
640 if (pad_mode == RSA_PKCS1_PADDING)
641 return 2;
642 if (pad_mode == RSA_PKCS1_PSS_PADDING) {
643 unsigned char aid[128];
644 size_t aid_len = 0;
645 OSSL_PARAM params[2];
646
647 if (evp_pkey_ctx_is_legacy(pkctx)) {
648 /* No provider -> we cannot query it for algorithm ID. */
649 ASN1_STRING *os1 = NULL;
650
651 os1 = ossl_rsa_ctx_to_pss_string(pkctx);
652 if (os1 == NULL)
653 return 0;
654 /* Duplicate parameters if we have to */
655 if (alg2 != NULL) {
656 ASN1_STRING *os2 = ASN1_STRING_dup(os1);
657
658 if (os2 == NULL) {
659 ASN1_STRING_free(os1);
660 return 0;
661 }
662 if (!X509_ALGOR_set0(alg2, OBJ_nid2obj(EVP_PKEY_RSA_PSS),
663 V_ASN1_SEQUENCE, os2)) {
664 ASN1_STRING_free(os1);
665 ASN1_STRING_free(os2);
666 return 0;
667 }
668 }
669 if (!X509_ALGOR_set0(alg1, OBJ_nid2obj(EVP_PKEY_RSA_PSS),
670 V_ASN1_SEQUENCE, os1)) {
671 ASN1_STRING_free(os1);
672 return 0;
673 }
674 return 3;
675 }
676
677 params[0] = OSSL_PARAM_construct_octet_string(
678 OSSL_SIGNATURE_PARAM_ALGORITHM_ID, aid, sizeof(aid));
679 params[1] = OSSL_PARAM_construct_end();
680
681 if (EVP_PKEY_CTX_get_params(pkctx, params) <= 0)
682 return 0;
683 if ((aid_len = params[0].return_size) == 0)
684 return 0;
685
686 if (alg1 != NULL) {
687 const unsigned char *pp = aid;
688
689 if (d2i_X509_ALGOR(&alg1, &pp, aid_len) == NULL)
690 return 0;
691 }
692 if (alg2 != NULL) {
693 const unsigned char *pp = aid;
694
695 if (d2i_X509_ALGOR(&alg2, &pp, aid_len) == NULL)
696 return 0;
697 }
698
699 return 3;
700 }
701 return 2;
702 }
703
rsa_sig_info_set(X509_SIG_INFO * siginf,const X509_ALGOR * sigalg,const ASN1_STRING * sig)704 static int rsa_sig_info_set(X509_SIG_INFO *siginf, const X509_ALGOR *sigalg,
705 const ASN1_STRING *sig)
706 {
707 int rv = 0;
708 int mdnid, saltlen;
709 uint32_t flags;
710 const EVP_MD *mgf1md = NULL, *md = NULL;
711 RSA_PSS_PARAMS *pss;
712 int secbits;
713
714 /* Sanity check: make sure it is PSS */
715 if (OBJ_obj2nid(sigalg->algorithm) != EVP_PKEY_RSA_PSS)
716 return 0;
717 /* Decode PSS parameters */
718 pss = ossl_rsa_pss_decode(sigalg);
719 if (!ossl_rsa_pss_get_param(pss, &md, &mgf1md, &saltlen))
720 goto err;
721 mdnid = EVP_MD_get_type(md);
722 /*
723 * For TLS need SHA256, SHA384 or SHA512, digest and MGF1 digest must
724 * match and salt length must equal digest size
725 */
726 if ((mdnid == NID_sha256 || mdnid == NID_sha384 || mdnid == NID_sha512)
727 && mdnid == EVP_MD_get_type(mgf1md)
728 && saltlen == EVP_MD_get_size(md))
729 flags = X509_SIG_INFO_TLS;
730 else
731 flags = 0;
732 /* Note: security bits half number of digest bits */
733 secbits = EVP_MD_get_size(md) * 4;
734 /*
735 * SHA1 and MD5 are known to be broken. Reduce security bits so that
736 * they're no longer accepted at security level 1. The real values don't
737 * really matter as long as they're lower than 80, which is our security
738 * level 1.
739 * https://eprint.iacr.org/2020/014 puts a chosen-prefix attack for SHA1 at
740 * 2^63.4
741 * https://documents.epfl.ch/users/l/le/lenstra/public/papers/lat.pdf
742 * puts a chosen-prefix attack for MD5 at 2^39.
743 */
744 if (mdnid == NID_sha1)
745 secbits = 64;
746 else if (mdnid == NID_md5_sha1)
747 secbits = 68;
748 else if (mdnid == NID_md5)
749 secbits = 39;
750 X509_SIG_INFO_set(siginf, mdnid, EVP_PKEY_RSA_PSS, secbits,
751 flags);
752 rv = 1;
753 err:
754 RSA_PSS_PARAMS_free(pss);
755 return rv;
756 }
757
rsa_pkey_check(const EVP_PKEY * pkey)758 static int rsa_pkey_check(const EVP_PKEY *pkey)
759 {
760 return RSA_check_key_ex(pkey->pkey.rsa, NULL);
761 }
762
rsa_pkey_dirty_cnt(const EVP_PKEY * pkey)763 static size_t rsa_pkey_dirty_cnt(const EVP_PKEY *pkey)
764 {
765 return pkey->pkey.rsa->dirty_cnt;
766 }
767
768 /*
769 * There is no need to do RSA_test_flags(rsa, RSA_FLAG_TYPE_RSASSAPSS)
770 * checks in this method since the caller tests EVP_KEYMGMT_is_a() first.
771 */
rsa_int_export_to(const EVP_PKEY * from,int rsa_type,void * to_keydata,OSSL_FUNC_keymgmt_import_fn * importer,OSSL_LIB_CTX * libctx,const char * propq)772 static int rsa_int_export_to(const EVP_PKEY *from, int rsa_type,
773 void *to_keydata,
774 OSSL_FUNC_keymgmt_import_fn *importer,
775 OSSL_LIB_CTX *libctx, const char *propq)
776 {
777 RSA *rsa = from->pkey.rsa;
778 OSSL_PARAM_BLD *tmpl = OSSL_PARAM_BLD_new();
779 OSSL_PARAM *params = NULL;
780 int selection = 0;
781 int rv = 0;
782
783 if (tmpl == NULL)
784 return 0;
785 /* Public parameters must always be present */
786 if (RSA_get0_n(rsa) == NULL || RSA_get0_e(rsa) == NULL)
787 goto err;
788
789 if (!ossl_rsa_todata(rsa, tmpl, NULL, 1))
790 goto err;
791
792 selection |= OSSL_KEYMGMT_SELECT_PUBLIC_KEY;
793 if (RSA_get0_d(rsa) != NULL)
794 selection |= OSSL_KEYMGMT_SELECT_PRIVATE_KEY;
795
796 if (rsa->pss != NULL) {
797 const EVP_MD *md = NULL, *mgf1md = NULL;
798 int md_nid, mgf1md_nid, saltlen, trailerfield;
799 RSA_PSS_PARAMS_30 pss_params;
800
801 if (!ossl_rsa_pss_get_param_unverified(rsa->pss, &md, &mgf1md,
802 &saltlen, &trailerfield))
803 goto err;
804 md_nid = EVP_MD_get_type(md);
805 mgf1md_nid = EVP_MD_get_type(mgf1md);
806 if (!ossl_rsa_pss_params_30_set_defaults(&pss_params)
807 || !ossl_rsa_pss_params_30_set_hashalg(&pss_params, md_nid)
808 || !ossl_rsa_pss_params_30_set_maskgenhashalg(&pss_params,
809 mgf1md_nid)
810 || !ossl_rsa_pss_params_30_set_saltlen(&pss_params, saltlen)
811 || !ossl_rsa_pss_params_30_todata(&pss_params, tmpl, NULL))
812 goto err;
813 selection |= OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS;
814 }
815
816 if ((params = OSSL_PARAM_BLD_to_param(tmpl)) == NULL)
817 goto err;
818
819 /* We export, the provider imports */
820 rv = importer(to_keydata, selection, params);
821
822 err:
823 OSSL_PARAM_free(params);
824 OSSL_PARAM_BLD_free(tmpl);
825 return rv;
826 }
827
rsa_int_import_from(const OSSL_PARAM params[],void * vpctx,int rsa_type)828 static int rsa_int_import_from(const OSSL_PARAM params[], void *vpctx,
829 int rsa_type)
830 {
831 EVP_PKEY_CTX *pctx = vpctx;
832 EVP_PKEY *pkey = EVP_PKEY_CTX_get0_pkey(pctx);
833 RSA *rsa = ossl_rsa_new_with_ctx(pctx->libctx);
834 RSA_PSS_PARAMS_30 rsa_pss_params = { 0, };
835 int pss_defaults_set = 0;
836 int ok = 0;
837
838 if (rsa == NULL) {
839 ERR_raise(ERR_LIB_DH, ERR_R_MALLOC_FAILURE);
840 return 0;
841 }
842
843 RSA_clear_flags(rsa, RSA_FLAG_TYPE_MASK);
844 RSA_set_flags(rsa, rsa_type);
845
846 if (!ossl_rsa_pss_params_30_fromdata(&rsa_pss_params, &pss_defaults_set,
847 params, pctx->libctx))
848 goto err;
849
850 switch (rsa_type) {
851 case RSA_FLAG_TYPE_RSA:
852 /*
853 * Were PSS parameters filled in?
854 * In that case, something's wrong
855 */
856 if (!ossl_rsa_pss_params_30_is_unrestricted(&rsa_pss_params))
857 goto err;
858 break;
859 case RSA_FLAG_TYPE_RSASSAPSS:
860 /*
861 * Were PSS parameters filled in? In that case, create the old
862 * RSA_PSS_PARAMS structure. Otherwise, this is an unrestricted key.
863 */
864 if (!ossl_rsa_pss_params_30_is_unrestricted(&rsa_pss_params)) {
865 /* Create the older RSA_PSS_PARAMS from RSA_PSS_PARAMS_30 data */
866 int mdnid = ossl_rsa_pss_params_30_hashalg(&rsa_pss_params);
867 int mgf1mdnid = ossl_rsa_pss_params_30_maskgenhashalg(&rsa_pss_params);
868 int saltlen = ossl_rsa_pss_params_30_saltlen(&rsa_pss_params);
869 const EVP_MD *md = EVP_get_digestbynid(mdnid);
870 const EVP_MD *mgf1md = EVP_get_digestbynid(mgf1mdnid);
871
872 if ((rsa->pss = ossl_rsa_pss_params_create(md, mgf1md,
873 saltlen)) == NULL)
874 goto err;
875 }
876 break;
877 default:
878 /* RSA key sub-types we don't know how to handle yet */
879 goto err;
880 }
881
882 if (!ossl_rsa_fromdata(rsa, params, 1))
883 goto err;
884
885 switch (rsa_type) {
886 case RSA_FLAG_TYPE_RSA:
887 ok = EVP_PKEY_assign_RSA(pkey, rsa);
888 break;
889 case RSA_FLAG_TYPE_RSASSAPSS:
890 ok = EVP_PKEY_assign(pkey, EVP_PKEY_RSA_PSS, rsa);
891 break;
892 }
893
894 err:
895 if (!ok)
896 RSA_free(rsa);
897 return ok;
898 }
899
rsa_pkey_export_to(const EVP_PKEY * from,void * to_keydata,OSSL_FUNC_keymgmt_import_fn * importer,OSSL_LIB_CTX * libctx,const char * propq)900 static int rsa_pkey_export_to(const EVP_PKEY *from, void *to_keydata,
901 OSSL_FUNC_keymgmt_import_fn *importer,
902 OSSL_LIB_CTX *libctx, const char *propq)
903 {
904 return rsa_int_export_to(from, RSA_FLAG_TYPE_RSA, to_keydata,
905 importer, libctx, propq);
906 }
907
rsa_pss_pkey_export_to(const EVP_PKEY * from,void * to_keydata,OSSL_FUNC_keymgmt_import_fn * importer,OSSL_LIB_CTX * libctx,const char * propq)908 static int rsa_pss_pkey_export_to(const EVP_PKEY *from, void *to_keydata,
909 OSSL_FUNC_keymgmt_import_fn *importer,
910 OSSL_LIB_CTX *libctx, const char *propq)
911 {
912 return rsa_int_export_to(from, RSA_FLAG_TYPE_RSASSAPSS, to_keydata,
913 importer, libctx, propq);
914 }
915
rsa_pkey_import_from(const OSSL_PARAM params[],void * vpctx)916 static int rsa_pkey_import_from(const OSSL_PARAM params[], void *vpctx)
917 {
918 return rsa_int_import_from(params, vpctx, RSA_FLAG_TYPE_RSA);
919 }
920
rsa_pss_pkey_import_from(const OSSL_PARAM params[],void * vpctx)921 static int rsa_pss_pkey_import_from(const OSSL_PARAM params[], void *vpctx)
922 {
923 return rsa_int_import_from(params, vpctx, RSA_FLAG_TYPE_RSASSAPSS);
924 }
925
rsa_pkey_copy(EVP_PKEY * to,EVP_PKEY * from)926 static int rsa_pkey_copy(EVP_PKEY *to, EVP_PKEY *from)
927 {
928 RSA *rsa = from->pkey.rsa;
929 RSA *dupkey = NULL;
930 int ret;
931
932 if (rsa != NULL) {
933 dupkey = ossl_rsa_dup(rsa, OSSL_KEYMGMT_SELECT_ALL);
934 if (dupkey == NULL)
935 return 0;
936 }
937
938 ret = EVP_PKEY_assign(to, from->type, dupkey);
939 if (!ret)
940 RSA_free(dupkey);
941 return ret;
942 }
943
944 const EVP_PKEY_ASN1_METHOD ossl_rsa_asn1_meths[2] = {
945 {
946 EVP_PKEY_RSA,
947 EVP_PKEY_RSA,
948 ASN1_PKEY_SIGPARAM_NULL,
949
950 "RSA",
951 "OpenSSL RSA method",
952
953 rsa_pub_decode,
954 rsa_pub_encode,
955 rsa_pub_cmp,
956 rsa_pub_print,
957
958 rsa_priv_decode,
959 rsa_priv_encode,
960 rsa_priv_print,
961
962 int_rsa_size,
963 rsa_bits,
964 rsa_security_bits,
965
966 0, 0, 0, 0, 0, 0,
967
968 rsa_sig_print,
969 int_rsa_free,
970 rsa_pkey_ctrl,
971 old_rsa_priv_decode,
972 old_rsa_priv_encode,
973 rsa_item_verify,
974 rsa_item_sign,
975 rsa_sig_info_set,
976 rsa_pkey_check,
977
978 0, 0,
979 0, 0, 0, 0,
980
981 rsa_pkey_dirty_cnt,
982 rsa_pkey_export_to,
983 rsa_pkey_import_from,
984 rsa_pkey_copy
985 },
986
987 {
988 EVP_PKEY_RSA2,
989 EVP_PKEY_RSA,
990 ASN1_PKEY_ALIAS}
991 };
992
993 const EVP_PKEY_ASN1_METHOD ossl_rsa_pss_asn1_meth = {
994 EVP_PKEY_RSA_PSS,
995 EVP_PKEY_RSA_PSS,
996 ASN1_PKEY_SIGPARAM_NULL,
997
998 "RSA-PSS",
999 "OpenSSL RSA-PSS method",
1000
1001 rsa_pub_decode,
1002 rsa_pub_encode,
1003 rsa_pub_cmp,
1004 rsa_pub_print,
1005
1006 rsa_priv_decode,
1007 rsa_priv_encode,
1008 rsa_priv_print,
1009
1010 int_rsa_size,
1011 rsa_bits,
1012 rsa_security_bits,
1013
1014 0, 0, 0, 0, 0, 0,
1015
1016 rsa_sig_print,
1017 int_rsa_free,
1018 rsa_pkey_ctrl,
1019 0, 0,
1020 rsa_item_verify,
1021 rsa_item_sign,
1022 rsa_sig_info_set,
1023 rsa_pkey_check,
1024
1025 0, 0,
1026 0, 0, 0, 0,
1027
1028 rsa_pkey_dirty_cnt,
1029 rsa_pss_pkey_export_to,
1030 rsa_pss_pkey_import_from,
1031 rsa_pkey_copy
1032 };
1033