Extend PSS padding code to support different digests for MGF1 and message.
[openssl.git] / crypto / rsa / rsa_pmeth.c
1 /* crypto/rsa/rsa_pmeth.c */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3  * project 2006.
4  */
5 /* ====================================================================
6  * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.
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  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer. 
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
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30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58
59 #include <stdio.h>
60 #include "cryptlib.h"
61 #include <openssl/asn1t.h>
62 #include <openssl/x509.h>
63 #include <openssl/rsa.h>
64 #include <openssl/bn.h>
65 #include <openssl/evp.h>
66 #include "evp_locl.h"
67 #include "rsa_locl.h"
68
69 /* RSA pkey context structure */
70
71 typedef struct
72         {
73         /* Key gen parameters */
74         int nbits;
75         BIGNUM *pub_exp;
76         /* Keygen callback info */
77         int gentmp[2];
78         /* RSA padding mode */
79         int pad_mode;
80         /* message digest */
81         const EVP_MD *md;
82         /* message digest for MGF1 */
83         const EVP_MD *mgf1md;
84         /* PSS/OAEP salt length */
85         int saltlen;
86         /* Temp buffer */
87         unsigned char *tbuf;
88         } RSA_PKEY_CTX;
89
90 static int pkey_rsa_init(EVP_PKEY_CTX *ctx)
91         {
92         RSA_PKEY_CTX *rctx;
93         rctx = OPENSSL_malloc(sizeof(RSA_PKEY_CTX));
94         if (!rctx)
95                 return 0;
96         rctx->nbits = 1024;
97         rctx->pub_exp = NULL;
98         rctx->pad_mode = RSA_PKCS1_PADDING;
99         rctx->md = NULL;
100         rctx->mgf1md = NULL;
101         rctx->tbuf = NULL;
102
103         rctx->saltlen = -2;
104
105         ctx->data = rctx;
106         ctx->keygen_info = rctx->gentmp;
107         ctx->keygen_info_count = 2;
108         
109         return 1;
110         }
111
112 static int pkey_rsa_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
113         {
114         RSA_PKEY_CTX *dctx, *sctx;
115         if (!pkey_rsa_init(dst))
116                 return 0;
117         sctx = src->data;
118         dctx = dst->data;
119         dctx->nbits = sctx->nbits;
120         if (sctx->pub_exp)
121                 {
122                 dctx->pub_exp = BN_dup(sctx->pub_exp);
123                 if (!dctx->pub_exp)
124                         return 0;
125                 }
126         dctx->pad_mode = sctx->pad_mode;
127         dctx->md = sctx->md;
128         return 1;
129         }
130
131 static int setup_tbuf(RSA_PKEY_CTX *ctx, EVP_PKEY_CTX *pk)
132         {
133         if (ctx->tbuf)
134                 return 1;
135         ctx->tbuf = OPENSSL_malloc(EVP_PKEY_size(pk->pkey));
136         if (!ctx->tbuf)
137                 return 0;
138         return 1;
139         }
140
141 static void pkey_rsa_cleanup(EVP_PKEY_CTX *ctx)
142         {
143         RSA_PKEY_CTX *rctx = ctx->data;
144         if (rctx)
145                 {
146                 if (rctx->pub_exp)
147                         BN_free(rctx->pub_exp);
148                 if (rctx->tbuf)
149                         OPENSSL_free(rctx->tbuf);
150                 OPENSSL_free(rctx);
151                 }
152         }
153
154 static int pkey_rsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen,
155                                         const unsigned char *tbs, size_t tbslen)
156         {
157         int ret;
158         RSA_PKEY_CTX *rctx = ctx->data;
159         RSA *rsa = ctx->pkey->pkey.rsa;
160
161         if (rctx->md)
162                 {
163                 if (tbslen != (size_t)EVP_MD_size(rctx->md))
164                         {
165                         RSAerr(RSA_F_PKEY_RSA_SIGN,
166                                         RSA_R_INVALID_DIGEST_LENGTH);
167                         return -1;
168                         }
169                 if (rctx->pad_mode == RSA_X931_PADDING)
170                         {
171                         if (!setup_tbuf(rctx, ctx))
172                                 return -1;
173                         memcpy(rctx->tbuf, tbs, tbslen);
174                         rctx->tbuf[tbslen] =
175                                 RSA_X931_hash_id(EVP_MD_type(rctx->md));
176                         ret = RSA_private_encrypt(tbslen + 1, rctx->tbuf,
177                                                 sig, rsa, RSA_X931_PADDING);
178                         }
179                 else if (rctx->pad_mode == RSA_PKCS1_PADDING)
180                         {
181                         unsigned int sltmp;
182                         ret = RSA_sign(EVP_MD_type(rctx->md),
183                                                 tbs, tbslen, sig, &sltmp, rsa);
184                         if (ret <= 0)
185                                 return ret;
186                         ret = sltmp;
187                         }
188                 else if (rctx->pad_mode == RSA_PKCS1_PSS_PADDING)
189                         {
190                         const EVP_MD *pssmd;
191                         pssmd = rctx->mgf1md;
192                         if (pssmd == NULL)
193                                 pssmd = rctx->md;
194                         if (!setup_tbuf(rctx, ctx))
195                                 return -1;
196                         if (!RSA_padding_add_PKCS1_PSS(rsa, rctx->tbuf, tbs,
197                                                 pssmd, rctx->saltlen))
198                                 return -1;
199                         ret = RSA_private_encrypt(RSA_size(rsa), rctx->tbuf,
200                                                 sig, rsa, RSA_NO_PADDING);
201                         }
202                 else
203                         return -1;
204                 }
205         else
206                 ret = RSA_private_encrypt(tbslen, tbs, sig, ctx->pkey->pkey.rsa,
207                                                         rctx->pad_mode);
208         if (ret < 0)
209                 return ret;
210         *siglen = ret;
211         return 1;
212         }
213
214
215 static int pkey_rsa_verifyrecover(EVP_PKEY_CTX *ctx,
216                                         unsigned char *rout, size_t *routlen,
217                                         const unsigned char *sig, size_t siglen)
218         {
219         int ret;
220         RSA_PKEY_CTX *rctx = ctx->data;
221
222         if (rctx->md)
223                 {
224                 if (rctx->pad_mode == RSA_X931_PADDING)
225                         {
226                         if (!setup_tbuf(rctx, ctx))
227                                 return -1;
228                         ret = RSA_public_decrypt(siglen, sig,
229                                                 rctx->tbuf, ctx->pkey->pkey.rsa,
230                                                 RSA_X931_PADDING);
231                         if (ret < 1)
232                                 return 0;
233                         ret--;
234                         if (rctx->tbuf[ret] !=
235                                 RSA_X931_hash_id(EVP_MD_type(rctx->md)))
236                                 {
237                                 RSAerr(RSA_F_PKEY_RSA_VERIFYRECOVER,
238                                                 RSA_R_ALGORITHM_MISMATCH);
239                                 return 0;
240                                 }
241                         if (ret != EVP_MD_size(rctx->md))
242                                 {
243                                 RSAerr(RSA_F_PKEY_RSA_VERIFYRECOVER,
244                                         RSA_R_INVALID_DIGEST_LENGTH);
245                                 return 0;
246                                 }
247                         if (rout)
248                                 memcpy(rout, rctx->tbuf, ret);
249                         }
250                 else if (rctx->pad_mode == RSA_PKCS1_PADDING)
251                         {
252                         size_t sltmp;
253                         ret = int_rsa_verify(EVP_MD_type(rctx->md),
254                                                 NULL, 0, rout, &sltmp,
255                                         sig, siglen, ctx->pkey->pkey.rsa);
256                         ret = sltmp;
257                         }
258                 else
259                         return -1;
260                 }
261         else
262                 ret = RSA_public_decrypt(siglen, sig, rout, ctx->pkey->pkey.rsa,
263                                                         rctx->pad_mode);
264         if (ret < 0)
265                 return ret;
266         *routlen = ret;
267         return 1;
268         }
269
270 static int pkey_rsa_verify(EVP_PKEY_CTX *ctx,
271                                         const unsigned char *sig, size_t siglen,
272                                         const unsigned char *tbs, size_t tbslen)
273         {
274         RSA_PKEY_CTX *rctx = ctx->data;
275         RSA *rsa = ctx->pkey->pkey.rsa;
276         size_t rslen;
277         if (rctx->md)
278                 {
279                 if (rctx->pad_mode == RSA_PKCS1_PADDING)
280                         return RSA_verify(EVP_MD_type(rctx->md), tbs, tbslen,
281                                         sig, siglen, rsa);
282                 if (rctx->pad_mode == RSA_X931_PADDING)
283                         {
284                         if (pkey_rsa_verifyrecover(ctx, NULL, &rslen,
285                                         sig, siglen) <= 0)
286                                 return 0;
287                         }
288                 else if (rctx->pad_mode == RSA_PKCS1_PSS_PADDING)
289                         {
290                         int ret;
291                         const EVP_MD *pssmd;
292                         pssmd = rctx->mgf1md;
293                         if (pssmd == NULL)
294                                 pssmd = rctx->md;
295                         if (!setup_tbuf(rctx, ctx))
296                                 return -1;
297                         ret = RSA_public_decrypt(siglen, sig, rctx->tbuf,
298                                                         rsa, RSA_NO_PADDING);
299                         if (ret <= 0)
300                                 return 0;
301                         ret = RSA_verify_PKCS1_PSS(rsa, tbs, pssmd,
302                                                 rctx->tbuf, rctx->saltlen);
303                         if (ret <= 0)
304                                 return 0;
305                         return 1;
306                         }
307                 else
308                         return -1;
309                 }
310         else
311                 {
312                 if (!setup_tbuf(rctx, ctx))
313                         return -1;
314                 rslen = RSA_public_decrypt(siglen, sig, rctx->tbuf,
315                                                 rsa, rctx->pad_mode);
316                 if (rslen == 0)
317                         return 0;
318                 }
319
320         if ((rslen != tbslen) || memcmp(tbs, rctx->tbuf, rslen))
321                 return 0;
322
323         return 1;
324                         
325         }
326         
327
328 static int pkey_rsa_encrypt(EVP_PKEY_CTX *ctx,
329                                         unsigned char *out, size_t *outlen,
330                                         const unsigned char *in, size_t inlen)
331         {
332         int ret;
333         RSA_PKEY_CTX *rctx = ctx->data;
334         ret = RSA_public_encrypt(inlen, in, out, ctx->pkey->pkey.rsa,
335                                                         rctx->pad_mode);
336         if (ret < 0)
337                 return ret;
338         *outlen = ret;
339         return 1;
340         }
341
342 static int pkey_rsa_decrypt(EVP_PKEY_CTX *ctx,
343                                         unsigned char *out, size_t *outlen,
344                                         const unsigned char *in, size_t inlen)
345         {
346         int ret;
347         RSA_PKEY_CTX *rctx = ctx->data;
348         ret = RSA_private_decrypt(inlen, in, out, ctx->pkey->pkey.rsa,
349                                                         rctx->pad_mode);
350         if (ret < 0)
351                 return ret;
352         *outlen = ret;
353         return 1;
354         }
355
356 static int check_padding_md(const EVP_MD *md, int padding)
357         {
358         if (!md)
359                 return 1;
360
361         if (padding == RSA_NO_PADDING)
362                 {
363                 RSAerr(RSA_F_CHECK_PADDING_MD, RSA_R_INVALID_PADDING_MODE);
364                 return 0;
365                 }
366
367         if (padding == RSA_X931_PADDING)
368                 {
369                 if (RSA_X931_hash_id(EVP_MD_type(md)) == -1)
370                         {
371                         RSAerr(RSA_F_CHECK_PADDING_MD,
372                                                 RSA_R_INVALID_X931_DIGEST);
373                         return 0;
374                         }
375                 return 1;
376                 }
377
378         return 1;
379         }
380                         
381
382 static int pkey_rsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
383         {
384         RSA_PKEY_CTX *rctx = ctx->data;
385         switch (type)
386                 {
387                 case EVP_PKEY_CTRL_RSA_PADDING:
388                 if ((p1 >= RSA_PKCS1_PADDING) && (p1 <= RSA_PKCS1_PSS_PADDING))
389                         {
390                         if (!check_padding_md(rctx->md, p1))
391                                 return 0;
392                         if (p1 == RSA_PKCS1_PSS_PADDING) 
393                                 {
394                                 if (!(ctx->operation &
395                                      (EVP_PKEY_OP_SIGN | EVP_PKEY_OP_VERIFY)))
396                                         goto bad_pad;
397                                 if (!rctx->md)
398                                         rctx->md = EVP_sha1();
399                                 }
400                         if (p1 == RSA_PKCS1_OAEP_PADDING) 
401                                 {
402                                 if (!(ctx->operation & EVP_PKEY_OP_TYPE_CRYPT))
403                                         goto bad_pad;
404                                 if (!rctx->md)
405                                         rctx->md = EVP_sha1();
406                                 }
407                         rctx->pad_mode = p1;
408                         return 1;
409                         }
410                 bad_pad:
411                 RSAerr(RSA_F_PKEY_RSA_CTRL,
412                                 RSA_R_ILLEGAL_OR_UNSUPPORTED_PADDING_MODE);
413                 return -2;
414
415                 case EVP_PKEY_CTRL_RSA_PSS_SALTLEN:
416                 if (p1 < -2)
417                         return -2;
418                 if (rctx->pad_mode != RSA_PKCS1_PSS_PADDING)
419                         {
420                         RSAerr(RSA_F_PKEY_RSA_CTRL, RSA_R_INVALID_PSS_SALTLEN);
421                         return -2;
422                         }
423                 rctx->saltlen = p1;
424                 return 1;
425
426                 case EVP_PKEY_CTRL_RSA_KEYGEN_BITS:
427                 if (p1 < 256)
428                         {
429                         RSAerr(RSA_F_PKEY_RSA_CTRL, RSA_R_INVALID_KEYBITS);
430                         return -2;
431                         }
432                 rctx->nbits = p1;
433                 return 1;
434
435                 case EVP_PKEY_CTRL_RSA_KEYGEN_PUBEXP:
436                 if (!p2)
437                         return -2;
438                 rctx->pub_exp = p2;
439                 return 1;
440
441                 case EVP_PKEY_CTRL_MD:
442                 if (!check_padding_md(p2, rctx->pad_mode))
443                         return 0;
444                 rctx->md = p2;
445                 return 1;
446
447                 case EVP_PKEY_CTRL_RSA_MGF1_MD:
448                 rctx->mgf1md = p2;
449                 return 1;
450
451                 case EVP_PKEY_CTRL_DIGESTINIT:
452                 case EVP_PKEY_CTRL_PKCS7_ENCRYPT:
453                 case EVP_PKEY_CTRL_PKCS7_DECRYPT:
454                 case EVP_PKEY_CTRL_PKCS7_SIGN:
455 #ifndef OPENSSL_NO_CMS
456                 case EVP_PKEY_CTRL_CMS_ENCRYPT:
457                 case EVP_PKEY_CTRL_CMS_DECRYPT:
458                 case EVP_PKEY_CTRL_CMS_SIGN:
459 #endif
460                 return 1;
461                 case EVP_PKEY_CTRL_PEER_KEY:
462                         RSAerr(RSA_F_PKEY_RSA_CTRL,
463                         RSA_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
464                         return -2;      
465
466                 default:
467                 return -2;
468
469                 }
470         }
471                         
472 static int pkey_rsa_ctrl_str(EVP_PKEY_CTX *ctx,
473                         const char *type, const char *value)
474         {
475         if (!value)
476                 {
477                 RSAerr(RSA_F_PKEY_RSA_CTRL_STR, RSA_R_VALUE_MISSING);
478                 return 0;
479                 }
480         if (!strcmp(type, "rsa_padding_mode"))
481                 {
482                 int pm;
483                 if (!strcmp(value, "pkcs1"))
484                         pm = RSA_PKCS1_PADDING;
485                 else if (!strcmp(value, "sslv23"))
486                         pm = RSA_SSLV23_PADDING;
487                 else if (!strcmp(value, "none"))
488                         pm = RSA_NO_PADDING;
489                 else if (!strcmp(value, "oeap"))
490                         pm = RSA_PKCS1_OAEP_PADDING;
491                 else if (!strcmp(value, "x931"))
492                         pm = RSA_X931_PADDING;
493                 else if (!strcmp(value, "pss"))
494                         pm = RSA_PKCS1_PSS_PADDING;
495                 else
496                         {
497                         RSAerr(RSA_F_PKEY_RSA_CTRL_STR,
498                                                 RSA_R_UNKNOWN_PADDING_TYPE);
499                         return -2;
500                         }
501                 return EVP_PKEY_CTX_set_rsa_padding(ctx, pm);
502                 }
503
504         if (!strcmp(type, "rsa_pss_saltlen"))
505                 {
506                 int saltlen;
507                 saltlen = atoi(value);
508                 return EVP_PKEY_CTX_set_rsa_pss_saltlen(ctx, saltlen);
509                 }
510
511         if (!strcmp(type, "rsa_keygen_bits"))
512                 {
513                 int nbits;
514                 nbits = atoi(value);
515                 return EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, nbits);
516                 }
517
518         if (!strcmp(type, "rsa_keygen_pubexp"))
519                 {
520                 int ret;
521                 BIGNUM *pubexp = NULL;
522                 if (!BN_asc2bn(&pubexp, value))
523                         return 0;
524                 ret = EVP_PKEY_CTX_set_rsa_keygen_pubexp(ctx, pubexp);
525                 if (ret <= 0)
526                         BN_free(pubexp);
527                 return ret;
528                 }
529
530         return -2;
531         }
532
533 static int pkey_rsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
534         {
535         RSA *rsa = NULL;
536         RSA_PKEY_CTX *rctx = ctx->data;
537         BN_GENCB *pcb, cb;
538         int ret;
539         if (!rctx->pub_exp)
540                 {
541                 rctx->pub_exp = BN_new();
542                 if (!rctx->pub_exp || !BN_set_word(rctx->pub_exp, RSA_F4))
543                         return 0;
544                 }
545         rsa = RSA_new();
546         if (!rsa)
547                 return 0;
548         if (ctx->pkey_gencb)
549                 {
550                 pcb = &cb;
551                 evp_pkey_set_cb_translate(pcb, ctx);
552                 }
553         else
554                 pcb = NULL;
555         ret = RSA_generate_key_ex(rsa, rctx->nbits, rctx->pub_exp, pcb);
556         if (ret > 0)
557                 EVP_PKEY_assign_RSA(pkey, rsa);
558         else
559                 RSA_free(rsa);
560         return ret;
561         }
562
563 const EVP_PKEY_METHOD rsa_pkey_meth = 
564         {
565         EVP_PKEY_RSA,
566         EVP_PKEY_FLAG_AUTOARGLEN,
567         pkey_rsa_init,
568         pkey_rsa_copy,
569         pkey_rsa_cleanup,
570
571         0,0,
572
573         0,
574         pkey_rsa_keygen,
575
576         0,
577         pkey_rsa_sign,
578
579         0,
580         pkey_rsa_verify,
581
582         0,
583         pkey_rsa_verifyrecover,
584
585
586         0,0,0,0,
587
588         0,
589         pkey_rsa_encrypt,
590
591         0,
592         pkey_rsa_decrypt,
593
594         0,0,
595
596         pkey_rsa_ctrl,
597         pkey_rsa_ctrl_str
598
599
600         };