xref: /freebsd/crypto/openssl/crypto/rsa/rsa_ameth.c (revision d9f0ce31900a48d1a2bfc1c8c86f79d1e831451a)
1 /* crypto/rsa/rsa_ameth.c */
2 /*
3  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
4  * 2006.
5  */
6 /* ====================================================================
7  * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. All advertising materials mentioning features or use of this
22  *    software must display the following acknowledgment:
23  *    "This product includes software developed by the OpenSSL Project
24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25  *
26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27  *    endorse or promote products derived from this software without
28  *    prior written permission. For written permission, please contact
29  *    licensing@OpenSSL.org.
30  *
31  * 5. Products derived from this software may not be called "OpenSSL"
32  *    nor may "OpenSSL" appear in their names without prior written
33  *    permission of the OpenSSL Project.
34  *
35  * 6. Redistributions of any form whatsoever must retain the following
36  *    acknowledgment:
37  *    "This product includes software developed by the OpenSSL Project
38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51  * OF THE POSSIBILITY OF SUCH DAMAGE.
52  * ====================================================================
53  *
54  * This product includes cryptographic software written by Eric Young
55  * (eay@cryptsoft.com).  This product includes software written by Tim
56  * Hudson (tjh@cryptsoft.com).
57  *
58  */
59 
60 #include <stdio.h>
61 #include "cryptlib.h"
62 #include <openssl/asn1t.h>
63 #include <openssl/x509.h>
64 #include <openssl/rsa.h>
65 #include <openssl/bn.h>
66 #ifndef OPENSSL_NO_CMS
67 # include <openssl/cms.h>
68 #endif
69 #include "asn1_locl.h"
70 
71 static int rsa_cms_sign(CMS_SignerInfo *si);
72 static int rsa_cms_verify(CMS_SignerInfo *si);
73 static int rsa_cms_decrypt(CMS_RecipientInfo *ri);
74 static int rsa_cms_encrypt(CMS_RecipientInfo *ri);
75 
76 static int rsa_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
77 {
78     unsigned char *penc = NULL;
79     int penclen;
80     penclen = i2d_RSAPublicKey(pkey->pkey.rsa, &penc);
81     if (penclen <= 0)
82         return 0;
83     if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_RSA),
84                                V_ASN1_NULL, NULL, penc, penclen))
85         return 1;
86 
87     OPENSSL_free(penc);
88     return 0;
89 }
90 
91 static int rsa_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
92 {
93     const unsigned char *p;
94     int pklen;
95     RSA *rsa = NULL;
96     if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, NULL, pubkey))
97         return 0;
98     if (!(rsa = d2i_RSAPublicKey(NULL, &p, pklen))) {
99         RSAerr(RSA_F_RSA_PUB_DECODE, ERR_R_RSA_LIB);
100         return 0;
101     }
102     EVP_PKEY_assign_RSA(pkey, rsa);
103     return 1;
104 }
105 
106 static int rsa_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
107 {
108     if (BN_cmp(b->pkey.rsa->n, a->pkey.rsa->n) != 0
109         || BN_cmp(b->pkey.rsa->e, a->pkey.rsa->e) != 0)
110         return 0;
111     return 1;
112 }
113 
114 static int old_rsa_priv_decode(EVP_PKEY *pkey,
115                                const unsigned char **pder, int derlen)
116 {
117     RSA *rsa;
118     if (!(rsa = d2i_RSAPrivateKey(NULL, pder, derlen))) {
119         RSAerr(RSA_F_OLD_RSA_PRIV_DECODE, ERR_R_RSA_LIB);
120         return 0;
121     }
122     EVP_PKEY_assign_RSA(pkey, rsa);
123     return 1;
124 }
125 
126 static int old_rsa_priv_encode(const EVP_PKEY *pkey, unsigned char **pder)
127 {
128     return i2d_RSAPrivateKey(pkey->pkey.rsa, pder);
129 }
130 
131 static int rsa_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
132 {
133     unsigned char *rk = NULL;
134     int rklen;
135     rklen = i2d_RSAPrivateKey(pkey->pkey.rsa, &rk);
136 
137     if (rklen <= 0) {
138         RSAerr(RSA_F_RSA_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
139         return 0;
140     }
141 
142     if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_rsaEncryption), 0,
143                          V_ASN1_NULL, NULL, rk, rklen)) {
144         RSAerr(RSA_F_RSA_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
145         return 0;
146     }
147 
148     return 1;
149 }
150 
151 static int rsa_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
152 {
153     const unsigned char *p;
154     int pklen;
155     if (!PKCS8_pkey_get0(NULL, &p, &pklen, NULL, p8))
156         return 0;
157     return old_rsa_priv_decode(pkey, &p, pklen);
158 }
159 
160 static int int_rsa_size(const EVP_PKEY *pkey)
161 {
162     return RSA_size(pkey->pkey.rsa);
163 }
164 
165 static int rsa_bits(const EVP_PKEY *pkey)
166 {
167     return BN_num_bits(pkey->pkey.rsa->n);
168 }
169 
170 static void int_rsa_free(EVP_PKEY *pkey)
171 {
172     RSA_free(pkey->pkey.rsa);
173 }
174 
175 static void update_buflen(const BIGNUM *b, size_t *pbuflen)
176 {
177     size_t i;
178     if (!b)
179         return;
180     if (*pbuflen < (i = (size_t)BN_num_bytes(b)))
181         *pbuflen = i;
182 }
183 
184 static int do_rsa_print(BIO *bp, const RSA *x, int off, int priv)
185 {
186     char *str;
187     const char *s;
188     unsigned char *m = NULL;
189     int ret = 0, mod_len = 0;
190     size_t buf_len = 0;
191 
192     update_buflen(x->n, &buf_len);
193     update_buflen(x->e, &buf_len);
194 
195     if (priv) {
196         update_buflen(x->d, &buf_len);
197         update_buflen(x->p, &buf_len);
198         update_buflen(x->q, &buf_len);
199         update_buflen(x->dmp1, &buf_len);
200         update_buflen(x->dmq1, &buf_len);
201         update_buflen(x->iqmp, &buf_len);
202     }
203 
204     m = (unsigned char *)OPENSSL_malloc(buf_len + 10);
205     if (m == NULL) {
206         RSAerr(RSA_F_DO_RSA_PRINT, ERR_R_MALLOC_FAILURE);
207         goto err;
208     }
209 
210     if (x->n != NULL)
211         mod_len = BN_num_bits(x->n);
212 
213     if (!BIO_indent(bp, off, 128))
214         goto err;
215 
216     if (priv && x->d) {
217         if (BIO_printf(bp, "Private-Key: (%d bit)\n", mod_len)
218             <= 0)
219             goto err;
220         str = "modulus:";
221         s = "publicExponent:";
222     } else {
223         if (BIO_printf(bp, "Public-Key: (%d bit)\n", mod_len)
224             <= 0)
225             goto err;
226         str = "Modulus:";
227         s = "Exponent:";
228     }
229     if (!ASN1_bn_print(bp, str, x->n, m, off))
230         goto err;
231     if (!ASN1_bn_print(bp, s, x->e, m, off))
232         goto err;
233     if (priv) {
234         if (!ASN1_bn_print(bp, "privateExponent:", x->d, m, off))
235             goto err;
236         if (!ASN1_bn_print(bp, "prime1:", x->p, m, off))
237             goto err;
238         if (!ASN1_bn_print(bp, "prime2:", x->q, m, off))
239             goto err;
240         if (!ASN1_bn_print(bp, "exponent1:", x->dmp1, m, off))
241             goto err;
242         if (!ASN1_bn_print(bp, "exponent2:", x->dmq1, m, off))
243             goto err;
244         if (!ASN1_bn_print(bp, "coefficient:", x->iqmp, m, off))
245             goto err;
246     }
247     ret = 1;
248  err:
249     if (m != NULL)
250         OPENSSL_free(m);
251     return (ret);
252 }
253 
254 static int rsa_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent,
255                          ASN1_PCTX *ctx)
256 {
257     return do_rsa_print(bp, pkey->pkey.rsa, indent, 0);
258 }
259 
260 static int rsa_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent,
261                           ASN1_PCTX *ctx)
262 {
263     return do_rsa_print(bp, pkey->pkey.rsa, indent, 1);
264 }
265 
266 /* Given an MGF1 Algorithm ID decode to an Algorithm Identifier */
267 static X509_ALGOR *rsa_mgf1_decode(X509_ALGOR *alg)
268 {
269     const unsigned char *p;
270     int plen;
271     if (alg == NULL || alg->parameter == NULL)
272         return NULL;
273     if (OBJ_obj2nid(alg->algorithm) != NID_mgf1)
274         return NULL;
275     if (alg->parameter->type != V_ASN1_SEQUENCE)
276         return NULL;
277 
278     p = alg->parameter->value.sequence->data;
279     plen = alg->parameter->value.sequence->length;
280     return d2i_X509_ALGOR(NULL, &p, plen);
281 }
282 
283 static RSA_PSS_PARAMS *rsa_pss_decode(const X509_ALGOR *alg,
284                                       X509_ALGOR **pmaskHash)
285 {
286     const unsigned char *p;
287     int plen;
288     RSA_PSS_PARAMS *pss;
289 
290     *pmaskHash = NULL;
291 
292     if (!alg->parameter || alg->parameter->type != V_ASN1_SEQUENCE)
293         return NULL;
294     p = alg->parameter->value.sequence->data;
295     plen = alg->parameter->value.sequence->length;
296     pss = d2i_RSA_PSS_PARAMS(NULL, &p, plen);
297 
298     if (!pss)
299         return NULL;
300 
301     *pmaskHash = rsa_mgf1_decode(pss->maskGenAlgorithm);
302 
303     return pss;
304 }
305 
306 static int rsa_pss_param_print(BIO *bp, RSA_PSS_PARAMS *pss,
307                                X509_ALGOR *maskHash, int indent)
308 {
309     int rv = 0;
310     if (!pss) {
311         if (BIO_puts(bp, " (INVALID PSS PARAMETERS)\n") <= 0)
312             return 0;
313         return 1;
314     }
315     if (BIO_puts(bp, "\n") <= 0)
316         goto err;
317     if (!BIO_indent(bp, indent, 128))
318         goto err;
319     if (BIO_puts(bp, "Hash Algorithm: ") <= 0)
320         goto err;
321 
322     if (pss->hashAlgorithm) {
323         if (i2a_ASN1_OBJECT(bp, pss->hashAlgorithm->algorithm) <= 0)
324             goto err;
325     } else if (BIO_puts(bp, "sha1 (default)") <= 0)
326         goto err;
327 
328     if (BIO_puts(bp, "\n") <= 0)
329         goto err;
330 
331     if (!BIO_indent(bp, indent, 128))
332         goto err;
333 
334     if (BIO_puts(bp, "Mask Algorithm: ") <= 0)
335         goto err;
336     if (pss->maskGenAlgorithm) {
337         if (i2a_ASN1_OBJECT(bp, pss->maskGenAlgorithm->algorithm) <= 0)
338             goto err;
339         if (BIO_puts(bp, " with ") <= 0)
340             goto err;
341         if (maskHash) {
342             if (i2a_ASN1_OBJECT(bp, maskHash->algorithm) <= 0)
343                 goto err;
344         } else if (BIO_puts(bp, "INVALID") <= 0)
345             goto err;
346     } else if (BIO_puts(bp, "mgf1 with sha1 (default)") <= 0)
347         goto err;
348     BIO_puts(bp, "\n");
349 
350     if (!BIO_indent(bp, indent, 128))
351         goto err;
352     if (BIO_puts(bp, "Salt Length: 0x") <= 0)
353         goto err;
354     if (pss->saltLength) {
355         if (i2a_ASN1_INTEGER(bp, pss->saltLength) <= 0)
356             goto err;
357     } else if (BIO_puts(bp, "14 (default)") <= 0)
358         goto err;
359     BIO_puts(bp, "\n");
360 
361     if (!BIO_indent(bp, indent, 128))
362         goto err;
363     if (BIO_puts(bp, "Trailer Field: 0x") <= 0)
364         goto err;
365     if (pss->trailerField) {
366         if (i2a_ASN1_INTEGER(bp, pss->trailerField) <= 0)
367             goto err;
368     } else if (BIO_puts(bp, "BC (default)") <= 0)
369         goto err;
370     BIO_puts(bp, "\n");
371 
372     rv = 1;
373 
374  err:
375     return rv;
376 
377 }
378 
379 static int rsa_sig_print(BIO *bp, const X509_ALGOR *sigalg,
380                          const ASN1_STRING *sig, int indent, ASN1_PCTX *pctx)
381 {
382     if (OBJ_obj2nid(sigalg->algorithm) == NID_rsassaPss) {
383         int rv;
384         RSA_PSS_PARAMS *pss;
385         X509_ALGOR *maskHash;
386         pss = rsa_pss_decode(sigalg, &maskHash);
387         rv = rsa_pss_param_print(bp, pss, maskHash, indent);
388         if (pss)
389             RSA_PSS_PARAMS_free(pss);
390         if (maskHash)
391             X509_ALGOR_free(maskHash);
392         if (!rv)
393             return 0;
394     } else if (!sig && BIO_puts(bp, "\n") <= 0)
395         return 0;
396     if (sig)
397         return X509_signature_dump(bp, sig, indent);
398     return 1;
399 }
400 
401 static int rsa_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
402 {
403     X509_ALGOR *alg = NULL;
404     switch (op) {
405 
406     case ASN1_PKEY_CTRL_PKCS7_SIGN:
407         if (arg1 == 0)
408             PKCS7_SIGNER_INFO_get0_algs(arg2, NULL, NULL, &alg);
409         break;
410 
411     case ASN1_PKEY_CTRL_PKCS7_ENCRYPT:
412         if (arg1 == 0)
413             PKCS7_RECIP_INFO_get0_alg(arg2, &alg);
414         break;
415 #ifndef OPENSSL_NO_CMS
416     case ASN1_PKEY_CTRL_CMS_SIGN:
417         if (arg1 == 0)
418             return rsa_cms_sign(arg2);
419         else if (arg1 == 1)
420             return rsa_cms_verify(arg2);
421         break;
422 
423     case ASN1_PKEY_CTRL_CMS_ENVELOPE:
424         if (arg1 == 0)
425             return rsa_cms_encrypt(arg2);
426         else if (arg1 == 1)
427             return rsa_cms_decrypt(arg2);
428         break;
429 
430     case ASN1_PKEY_CTRL_CMS_RI_TYPE:
431         *(int *)arg2 = CMS_RECIPINFO_TRANS;
432         return 1;
433 #endif
434 
435     case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
436         *(int *)arg2 = NID_sha256;
437         return 1;
438 
439     default:
440         return -2;
441 
442     }
443 
444     if (alg)
445         X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
446 
447     return 1;
448 
449 }
450 
451 /* allocate and set algorithm ID from EVP_MD, default SHA1 */
452 static int rsa_md_to_algor(X509_ALGOR **palg, const EVP_MD *md)
453 {
454     if (EVP_MD_type(md) == NID_sha1)
455         return 1;
456     *palg = X509_ALGOR_new();
457     if (!*palg)
458         return 0;
459     X509_ALGOR_set_md(*palg, md);
460     return 1;
461 }
462 
463 /* Allocate and set MGF1 algorithm ID from EVP_MD */
464 static int rsa_md_to_mgf1(X509_ALGOR **palg, const EVP_MD *mgf1md)
465 {
466     X509_ALGOR *algtmp = NULL;
467     ASN1_STRING *stmp = NULL;
468     *palg = NULL;
469     if (EVP_MD_type(mgf1md) == NID_sha1)
470         return 1;
471     /* need to embed algorithm ID inside another */
472     if (!rsa_md_to_algor(&algtmp, mgf1md))
473         goto err;
474     if (!ASN1_item_pack(algtmp, ASN1_ITEM_rptr(X509_ALGOR), &stmp))
475          goto err;
476     *palg = X509_ALGOR_new();
477     if (!*palg)
478         goto err;
479     X509_ALGOR_set0(*palg, OBJ_nid2obj(NID_mgf1), V_ASN1_SEQUENCE, stmp);
480     stmp = NULL;
481  err:
482     if (stmp)
483         ASN1_STRING_free(stmp);
484     if (algtmp)
485         X509_ALGOR_free(algtmp);
486     if (*palg)
487         return 1;
488     return 0;
489 }
490 
491 /* convert algorithm ID to EVP_MD, default SHA1 */
492 static const EVP_MD *rsa_algor_to_md(X509_ALGOR *alg)
493 {
494     const EVP_MD *md;
495     if (!alg)
496         return EVP_sha1();
497     md = EVP_get_digestbyobj(alg->algorithm);
498     if (md == NULL)
499         RSAerr(RSA_F_RSA_ALGOR_TO_MD, RSA_R_UNKNOWN_DIGEST);
500     return md;
501 }
502 
503 /* convert MGF1 algorithm ID to EVP_MD, default SHA1 */
504 static const EVP_MD *rsa_mgf1_to_md(X509_ALGOR *alg, X509_ALGOR *maskHash)
505 {
506     const EVP_MD *md;
507     if (!alg)
508         return EVP_sha1();
509     /* Check mask and lookup mask hash algorithm */
510     if (OBJ_obj2nid(alg->algorithm) != NID_mgf1) {
511         RSAerr(RSA_F_RSA_MGF1_TO_MD, RSA_R_UNSUPPORTED_MASK_ALGORITHM);
512         return NULL;
513     }
514     if (!maskHash) {
515         RSAerr(RSA_F_RSA_MGF1_TO_MD, RSA_R_UNSUPPORTED_MASK_PARAMETER);
516         return NULL;
517     }
518     md = EVP_get_digestbyobj(maskHash->algorithm);
519     if (md == NULL) {
520         RSAerr(RSA_F_RSA_MGF1_TO_MD, RSA_R_UNKNOWN_MASK_DIGEST);
521         return NULL;
522     }
523     return md;
524 }
525 
526 /*
527  * Convert EVP_PKEY_CTX is PSS mode into corresponding algorithm parameter,
528  * suitable for setting an AlgorithmIdentifier.
529  */
530 
531 static ASN1_STRING *rsa_ctx_to_pss(EVP_PKEY_CTX *pkctx)
532 {
533     const EVP_MD *sigmd, *mgf1md;
534     RSA_PSS_PARAMS *pss = NULL;
535     ASN1_STRING *os = NULL;
536     EVP_PKEY *pk = EVP_PKEY_CTX_get0_pkey(pkctx);
537     int saltlen, rv = 0;
538     if (EVP_PKEY_CTX_get_signature_md(pkctx, &sigmd) <= 0)
539         goto err;
540     if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
541         goto err;
542     if (!EVP_PKEY_CTX_get_rsa_pss_saltlen(pkctx, &saltlen))
543         goto err;
544     if (saltlen == -1)
545         saltlen = EVP_MD_size(sigmd);
546     else if (saltlen == -2) {
547         saltlen = EVP_PKEY_size(pk) - EVP_MD_size(sigmd) - 2;
548         if (((EVP_PKEY_bits(pk) - 1) & 0x7) == 0)
549             saltlen--;
550     }
551     pss = RSA_PSS_PARAMS_new();
552     if (!pss)
553         goto err;
554     if (saltlen != 20) {
555         pss->saltLength = ASN1_INTEGER_new();
556         if (!pss->saltLength)
557             goto err;
558         if (!ASN1_INTEGER_set(pss->saltLength, saltlen))
559             goto err;
560     }
561     if (!rsa_md_to_algor(&pss->hashAlgorithm, sigmd))
562         goto err;
563     if (!rsa_md_to_mgf1(&pss->maskGenAlgorithm, mgf1md))
564         goto err;
565     /* Finally create string with pss parameter encoding. */
566     if (!ASN1_item_pack(pss, ASN1_ITEM_rptr(RSA_PSS_PARAMS), &os))
567          goto err;
568     rv = 1;
569  err:
570     if (pss)
571         RSA_PSS_PARAMS_free(pss);
572     if (rv)
573         return os;
574     if (os)
575         ASN1_STRING_free(os);
576     return NULL;
577 }
578 
579 /*
580  * From PSS AlgorithmIdentifier set public key parameters. If pkey isn't NULL
581  * then the EVP_MD_CTX is setup and initalised. If it is NULL parameters are
582  * passed to pkctx instead.
583  */
584 
585 static int rsa_pss_to_ctx(EVP_MD_CTX *ctx, EVP_PKEY_CTX *pkctx,
586                           X509_ALGOR *sigalg, EVP_PKEY *pkey)
587 {
588     int rv = -1;
589     int saltlen;
590     const EVP_MD *mgf1md = NULL, *md = NULL;
591     RSA_PSS_PARAMS *pss;
592     X509_ALGOR *maskHash;
593     /* Sanity check: make sure it is PSS */
594     if (OBJ_obj2nid(sigalg->algorithm) != NID_rsassaPss) {
595         RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
596         return -1;
597     }
598     /* Decode PSS parameters */
599     pss = rsa_pss_decode(sigalg, &maskHash);
600 
601     if (pss == NULL) {
602         RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_INVALID_PSS_PARAMETERS);
603         goto err;
604     }
605     mgf1md = rsa_mgf1_to_md(pss->maskGenAlgorithm, maskHash);
606     if (!mgf1md)
607         goto err;
608     md = rsa_algor_to_md(pss->hashAlgorithm);
609     if (!md)
610         goto err;
611 
612     if (pss->saltLength) {
613         saltlen = ASN1_INTEGER_get(pss->saltLength);
614 
615         /*
616          * Could perform more salt length sanity checks but the main RSA
617          * routines will trap other invalid values anyway.
618          */
619         if (saltlen < 0) {
620             RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_INVALID_SALT_LENGTH);
621             goto err;
622         }
623     } else
624         saltlen = 20;
625 
626     /*
627      * low-level routines support only trailer field 0xbc (value 1) and
628      * PKCS#1 says we should reject any other value anyway.
629      */
630     if (pss->trailerField && ASN1_INTEGER_get(pss->trailerField) != 1) {
631         RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_INVALID_TRAILER);
632         goto err;
633     }
634 
635     /* We have all parameters now set up context */
636 
637     if (pkey) {
638         if (!EVP_DigestVerifyInit(ctx, &pkctx, md, NULL, pkey))
639             goto err;
640     } else {
641         const EVP_MD *checkmd;
642         if (EVP_PKEY_CTX_get_signature_md(pkctx, &checkmd) <= 0)
643             goto err;
644         if (EVP_MD_type(md) != EVP_MD_type(checkmd)) {
645             RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_DIGEST_DOES_NOT_MATCH);
646             goto err;
647         }
648     }
649 
650     if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_PSS_PADDING) <= 0)
651         goto err;
652 
653     if (EVP_PKEY_CTX_set_rsa_pss_saltlen(pkctx, saltlen) <= 0)
654         goto err;
655 
656     if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
657         goto err;
658     /* Carry on */
659     rv = 1;
660 
661  err:
662     RSA_PSS_PARAMS_free(pss);
663     if (maskHash)
664         X509_ALGOR_free(maskHash);
665     return rv;
666 }
667 
668 static int rsa_cms_verify(CMS_SignerInfo *si)
669 {
670     int nid, nid2;
671     X509_ALGOR *alg;
672     EVP_PKEY_CTX *pkctx = CMS_SignerInfo_get0_pkey_ctx(si);
673     CMS_SignerInfo_get0_algs(si, NULL, NULL, NULL, &alg);
674     nid = OBJ_obj2nid(alg->algorithm);
675     if (nid == NID_rsaEncryption)
676         return 1;
677     if (nid == NID_rsassaPss)
678         return rsa_pss_to_ctx(NULL, pkctx, alg, NULL);
679     /* Workaround for some implementation that use a signature OID */
680     if (OBJ_find_sigid_algs(nid, NULL, &nid2)) {
681         if (nid2 == NID_rsaEncryption)
682             return 1;
683     }
684     return 0;
685 }
686 
687 /*
688  * Customised RSA item verification routine. This is called when a signature
689  * is encountered requiring special handling. We currently only handle PSS.
690  */
691 
692 static int rsa_item_verify(EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
693                            X509_ALGOR *sigalg, ASN1_BIT_STRING *sig,
694                            EVP_PKEY *pkey)
695 {
696     /* Sanity check: make sure it is PSS */
697     if (OBJ_obj2nid(sigalg->algorithm) != NID_rsassaPss) {
698         RSAerr(RSA_F_RSA_ITEM_VERIFY, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
699         return -1;
700     }
701     if (rsa_pss_to_ctx(ctx, NULL, sigalg, pkey) > 0) {
702         /* Carry on */
703         return 2;
704     }
705     return -1;
706 }
707 
708 static int rsa_cms_sign(CMS_SignerInfo *si)
709 {
710     int pad_mode = RSA_PKCS1_PADDING;
711     X509_ALGOR *alg;
712     EVP_PKEY_CTX *pkctx = CMS_SignerInfo_get0_pkey_ctx(si);
713     ASN1_STRING *os = NULL;
714     CMS_SignerInfo_get0_algs(si, NULL, NULL, NULL, &alg);
715     if (pkctx) {
716         if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
717             return 0;
718     }
719     if (pad_mode == RSA_PKCS1_PADDING) {
720         X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
721         return 1;
722     }
723     /* We don't support it */
724     if (pad_mode != RSA_PKCS1_PSS_PADDING)
725         return 0;
726     os = rsa_ctx_to_pss(pkctx);
727     if (!os)
728         return 0;
729     X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsassaPss), V_ASN1_SEQUENCE, os);
730     return 1;
731 }
732 
733 static int rsa_item_sign(EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
734                          X509_ALGOR *alg1, X509_ALGOR *alg2,
735                          ASN1_BIT_STRING *sig)
736 {
737     int pad_mode;
738     EVP_PKEY_CTX *pkctx = ctx->pctx;
739     if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
740         return 0;
741     if (pad_mode == RSA_PKCS1_PADDING)
742         return 2;
743     if (pad_mode == RSA_PKCS1_PSS_PADDING) {
744         ASN1_STRING *os1 = NULL;
745         os1 = rsa_ctx_to_pss(pkctx);
746         if (!os1)
747             return 0;
748         /* Duplicate parameters if we have to */
749         if (alg2) {
750             ASN1_STRING *os2 = ASN1_STRING_dup(os1);
751             if (!os2) {
752                 ASN1_STRING_free(os1);
753                 return 0;
754             }
755             X509_ALGOR_set0(alg2, OBJ_nid2obj(NID_rsassaPss),
756                             V_ASN1_SEQUENCE, os2);
757         }
758         X509_ALGOR_set0(alg1, OBJ_nid2obj(NID_rsassaPss),
759                         V_ASN1_SEQUENCE, os1);
760         return 3;
761     }
762     return 2;
763 }
764 
765 static RSA_OAEP_PARAMS *rsa_oaep_decode(const X509_ALGOR *alg,
766                                         X509_ALGOR **pmaskHash)
767 {
768     const unsigned char *p;
769     int plen;
770     RSA_OAEP_PARAMS *pss;
771 
772     *pmaskHash = NULL;
773 
774     if (!alg->parameter || alg->parameter->type != V_ASN1_SEQUENCE)
775         return NULL;
776     p = alg->parameter->value.sequence->data;
777     plen = alg->parameter->value.sequence->length;
778     pss = d2i_RSA_OAEP_PARAMS(NULL, &p, plen);
779 
780     if (!pss)
781         return NULL;
782 
783     *pmaskHash = rsa_mgf1_decode(pss->maskGenFunc);
784 
785     return pss;
786 }
787 
788 static int rsa_cms_decrypt(CMS_RecipientInfo *ri)
789 {
790     EVP_PKEY_CTX *pkctx;
791     X509_ALGOR *cmsalg;
792     int nid;
793     int rv = -1;
794     unsigned char *label = NULL;
795     int labellen = 0;
796     const EVP_MD *mgf1md = NULL, *md = NULL;
797     RSA_OAEP_PARAMS *oaep;
798     X509_ALGOR *maskHash;
799     pkctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
800     if (!pkctx)
801         return 0;
802     if (!CMS_RecipientInfo_ktri_get0_algs(ri, NULL, NULL, &cmsalg))
803         return -1;
804     nid = OBJ_obj2nid(cmsalg->algorithm);
805     if (nid == NID_rsaEncryption)
806         return 1;
807     if (nid != NID_rsaesOaep) {
808         RSAerr(RSA_F_RSA_CMS_DECRYPT, RSA_R_UNSUPPORTED_ENCRYPTION_TYPE);
809         return -1;
810     }
811     /* Decode OAEP parameters */
812     oaep = rsa_oaep_decode(cmsalg, &maskHash);
813 
814     if (oaep == NULL) {
815         RSAerr(RSA_F_RSA_CMS_DECRYPT, RSA_R_INVALID_OAEP_PARAMETERS);
816         goto err;
817     }
818 
819     mgf1md = rsa_mgf1_to_md(oaep->maskGenFunc, maskHash);
820     if (!mgf1md)
821         goto err;
822     md = rsa_algor_to_md(oaep->hashFunc);
823     if (!md)
824         goto err;
825 
826     if (oaep->pSourceFunc) {
827         X509_ALGOR *plab = oaep->pSourceFunc;
828         if (OBJ_obj2nid(plab->algorithm) != NID_pSpecified) {
829             RSAerr(RSA_F_RSA_CMS_DECRYPT, RSA_R_UNSUPPORTED_LABEL_SOURCE);
830             goto err;
831         }
832         if (plab->parameter->type != V_ASN1_OCTET_STRING) {
833             RSAerr(RSA_F_RSA_CMS_DECRYPT, RSA_R_INVALID_LABEL);
834             goto err;
835         }
836 
837         label = plab->parameter->value.octet_string->data;
838         /* Stop label being freed when OAEP parameters are freed */
839         plab->parameter->value.octet_string->data = NULL;
840         labellen = plab->parameter->value.octet_string->length;
841     }
842 
843     if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_OAEP_PADDING) <= 0)
844         goto err;
845     if (EVP_PKEY_CTX_set_rsa_oaep_md(pkctx, md) <= 0)
846         goto err;
847     if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
848         goto err;
849     if (EVP_PKEY_CTX_set0_rsa_oaep_label(pkctx, label, labellen) <= 0)
850         goto err;
851     /* Carry on */
852     rv = 1;
853 
854  err:
855     RSA_OAEP_PARAMS_free(oaep);
856     if (maskHash)
857         X509_ALGOR_free(maskHash);
858     return rv;
859 }
860 
861 static int rsa_cms_encrypt(CMS_RecipientInfo *ri)
862 {
863     const EVP_MD *md, *mgf1md;
864     RSA_OAEP_PARAMS *oaep = NULL;
865     ASN1_STRING *os = NULL;
866     X509_ALGOR *alg;
867     EVP_PKEY_CTX *pkctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
868     int pad_mode = RSA_PKCS1_PADDING, rv = 0, labellen;
869     unsigned char *label;
870     CMS_RecipientInfo_ktri_get0_algs(ri, NULL, NULL, &alg);
871     if (pkctx) {
872         if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
873             return 0;
874     }
875     if (pad_mode == RSA_PKCS1_PADDING) {
876         X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
877         return 1;
878     }
879     /* Not supported */
880     if (pad_mode != RSA_PKCS1_OAEP_PADDING)
881         return 0;
882     if (EVP_PKEY_CTX_get_rsa_oaep_md(pkctx, &md) <= 0)
883         goto err;
884     if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
885         goto err;
886     labellen = EVP_PKEY_CTX_get0_rsa_oaep_label(pkctx, &label);
887     if (labellen < 0)
888         goto err;
889     oaep = RSA_OAEP_PARAMS_new();
890     if (!oaep)
891         goto err;
892     if (!rsa_md_to_algor(&oaep->hashFunc, md))
893         goto err;
894     if (!rsa_md_to_mgf1(&oaep->maskGenFunc, mgf1md))
895         goto err;
896     if (labellen > 0) {
897         ASN1_OCTET_STRING *los = ASN1_OCTET_STRING_new();
898         oaep->pSourceFunc = X509_ALGOR_new();
899         if (!oaep->pSourceFunc)
900             goto err;
901         if (!los)
902             goto err;
903         if (!ASN1_OCTET_STRING_set(los, label, labellen)) {
904             ASN1_OCTET_STRING_free(los);
905             goto err;
906         }
907         X509_ALGOR_set0(oaep->pSourceFunc, OBJ_nid2obj(NID_pSpecified),
908                         V_ASN1_OCTET_STRING, los);
909     }
910     /* create string with pss parameter encoding. */
911     if (!ASN1_item_pack(oaep, ASN1_ITEM_rptr(RSA_OAEP_PARAMS), &os))
912          goto err;
913     X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaesOaep), V_ASN1_SEQUENCE, os);
914     os = NULL;
915     rv = 1;
916  err:
917     if (oaep)
918         RSA_OAEP_PARAMS_free(oaep);
919     if (os)
920         ASN1_STRING_free(os);
921     return rv;
922 }
923 
924 const EVP_PKEY_ASN1_METHOD rsa_asn1_meths[] = {
925     {
926      EVP_PKEY_RSA,
927      EVP_PKEY_RSA,
928      ASN1_PKEY_SIGPARAM_NULL,
929 
930      "RSA",
931      "OpenSSL RSA method",
932 
933      rsa_pub_decode,
934      rsa_pub_encode,
935      rsa_pub_cmp,
936      rsa_pub_print,
937 
938      rsa_priv_decode,
939      rsa_priv_encode,
940      rsa_priv_print,
941 
942      int_rsa_size,
943      rsa_bits,
944 
945      0, 0, 0, 0, 0, 0,
946 
947      rsa_sig_print,
948      int_rsa_free,
949      rsa_pkey_ctrl,
950      old_rsa_priv_decode,
951      old_rsa_priv_encode,
952      rsa_item_verify,
953      rsa_item_sign},
954 
955     {
956      EVP_PKEY_RSA2,
957      EVP_PKEY_RSA,
958      ASN1_PKEY_ALIAS}
959 };
960