1 /* crypto/rsa/rsa_eay.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
61 #include <openssl/bn.h>
62 #include <openssl/rsa.h>
63 #include <openssl/rand.h>
64 #include <openssl/engine.h>
68 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
69 unsigned char *to, RSA *rsa,int padding);
70 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
71 unsigned char *to, RSA *rsa,int padding);
72 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
73 unsigned char *to, RSA *rsa,int padding);
74 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
75 unsigned char *to, RSA *rsa,int padding);
76 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa);
77 static int RSA_eay_init(RSA *rsa);
78 static int RSA_eay_finish(RSA *rsa);
79 static RSA_METHOD rsa_pkcs1_eay_meth={
80 "Eric Young's PKCS#1 RSA",
81 RSA_eay_public_encrypt,
82 RSA_eay_public_decrypt, /* signature verification */
83 RSA_eay_private_encrypt, /* signing */
84 RSA_eay_private_decrypt,
86 BN_mod_exp_mont, /* XXX probably we should not use Montgomery if e == 3 */
95 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
97 return(&rsa_pkcs1_eay_meth);
100 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
101 unsigned char *to, RSA *rsa, int padding)
104 int i,j,k,num=0,r= -1;
105 unsigned char *buf=NULL;
110 if ((ctx=BN_CTX_new()) == NULL) goto err;
111 num=BN_num_bytes(rsa->n);
112 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
114 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
120 case RSA_PKCS1_PADDING:
121 i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
123 #ifndef OPENSSL_NO_SHA
124 case RSA_PKCS1_OAEP_PADDING:
125 i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
128 case RSA_SSLV23_PADDING:
129 i=RSA_padding_add_SSLv23(buf,num,from,flen);
132 i=RSA_padding_add_none(buf,num,from,flen);
135 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
138 if (i <= 0) goto err;
140 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
142 if (BN_ucmp(&f, rsa->n) >= 0)
144 /* usually the padding functions would catch this */
145 RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
149 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
151 BN_MONT_CTX* bn_mont_ctx;
152 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
154 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
156 BN_MONT_CTX_free(bn_mont_ctx);
159 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
161 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
162 if (rsa->_method_mod_n == NULL)
164 rsa->_method_mod_n = bn_mont_ctx;
167 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
170 BN_MONT_CTX_free(bn_mont_ctx);
173 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
174 rsa->_method_mod_n)) goto err;
176 /* put in leading 0 bytes if the number is less than the
177 * length of the modulus */
178 j=BN_num_bytes(&ret);
179 i=BN_bn2bin(&ret,&(to[num-j]));
180 for (k=0; k<(num-i); k++)
185 if (ctx != NULL) BN_CTX_free(ctx);
197 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
198 unsigned char *to, RSA *rsa, int padding)
201 int i,j,k,num=0,r= -1;
202 unsigned char *buf=NULL;
208 if ((ctx=BN_CTX_new()) == NULL) goto err;
209 num=BN_num_bytes(rsa->n);
210 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
212 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
218 case RSA_PKCS1_PADDING:
219 i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
222 i=RSA_padding_add_none(buf,num,from,flen);
224 case RSA_SSLV23_PADDING:
226 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
229 if (i <= 0) goto err;
231 if (BN_bin2bn(buf,num,&f) == NULL) goto err;
233 if (BN_ucmp(&f, rsa->n) >= 0)
235 /* usually the padding functions would catch this */
236 RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
240 if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
241 RSA_blinding_on(rsa,ctx);
242 if (rsa->flags & RSA_FLAG_BLINDING)
243 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
245 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
248 (rsa->dmp1 != NULL) &&
249 (rsa->dmq1 != NULL) &&
250 (rsa->iqmp != NULL)) )
251 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
254 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err;
257 if (rsa->flags & RSA_FLAG_BLINDING)
258 if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err;
260 /* put in leading 0 bytes if the number is less than the
261 * length of the modulus */
262 j=BN_num_bytes(&ret);
263 i=BN_bn2bin(&ret,&(to[num-j]));
264 for (k=0; k<(num-i); k++)
269 if (ctx != NULL) BN_CTX_free(ctx);
280 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
281 unsigned char *to, RSA *rsa, int padding)
286 unsigned char *buf=NULL;
292 if (ctx == NULL) goto err;
294 num=BN_num_bytes(rsa->n);
296 if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
298 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
302 /* This check was for equality but PGP does evil things
303 * and chops off the top '0' bytes */
306 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
310 /* make data into a big number */
311 if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err;
313 if (BN_ucmp(&f, rsa->n) >= 0)
315 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
319 if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
320 RSA_blinding_on(rsa,ctx);
321 if (rsa->flags & RSA_FLAG_BLINDING)
322 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
325 if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
328 (rsa->dmp1 != NULL) &&
329 (rsa->dmq1 != NULL) &&
330 (rsa->iqmp != NULL)) )
331 { if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
334 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL))
338 if (rsa->flags & RSA_FLAG_BLINDING)
339 if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err;
342 j=BN_bn2bin(&ret,p); /* j is only used with no-padding mode */
346 case RSA_PKCS1_PADDING:
347 r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
349 #ifndef OPENSSL_NO_SHA
350 case RSA_PKCS1_OAEP_PADDING:
351 r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
354 case RSA_SSLV23_PADDING:
355 r=RSA_padding_check_SSLv23(to,num,buf,j,num);
358 r=RSA_padding_check_none(to,num,buf,j,num);
361 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
365 RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
368 if (ctx != NULL) BN_CTX_free(ctx);
379 /* signature verification */
380 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
381 unsigned char *to, RSA *rsa, int padding)
386 unsigned char *buf=NULL;
392 if (ctx == NULL) goto err;
394 num=BN_num_bytes(rsa->n);
395 buf=(unsigned char *)OPENSSL_malloc(num);
398 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
402 /* This check was for equality but PGP does evil things
403 * and chops off the top '0' bytes */
406 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
410 if (BN_bin2bn(from,flen,&f) == NULL) goto err;
412 if (BN_ucmp(&f, rsa->n) >= 0)
414 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
419 if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
421 BN_MONT_CTX* bn_mont_ctx;
422 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
424 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->n,ctx))
426 BN_MONT_CTX_free(bn_mont_ctx);
429 if (rsa->_method_mod_n == NULL) /* other thread may have finished first */
431 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
432 if (rsa->_method_mod_n == NULL)
434 rsa->_method_mod_n = bn_mont_ctx;
437 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
440 BN_MONT_CTX_free(bn_mont_ctx);
443 if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
444 rsa->_method_mod_n)) goto err;
451 case RSA_PKCS1_PADDING:
452 r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
455 r=RSA_padding_check_none(to,num,buf,i,num);
458 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
462 RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
465 if (ctx != NULL) BN_CTX_free(ctx);
476 static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
485 if ((ctx=BN_CTX_new()) == NULL) goto err;
487 if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
489 if (rsa->_method_mod_p == NULL)
491 BN_MONT_CTX* bn_mont_ctx;
492 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
494 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->p,ctx))
496 BN_MONT_CTX_free(bn_mont_ctx);
499 if (rsa->_method_mod_p == NULL) /* other thread may have finished first */
501 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
502 if (rsa->_method_mod_p == NULL)
504 rsa->_method_mod_p = bn_mont_ctx;
507 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
510 BN_MONT_CTX_free(bn_mont_ctx);
513 if (rsa->_method_mod_q == NULL)
515 BN_MONT_CTX* bn_mont_ctx;
516 if ((bn_mont_ctx=BN_MONT_CTX_new()) == NULL)
518 if (!BN_MONT_CTX_set(bn_mont_ctx,rsa->q,ctx))
520 BN_MONT_CTX_free(bn_mont_ctx);
523 if (rsa->_method_mod_q == NULL) /* other thread may have finished first */
525 CRYPTO_w_lock(CRYPTO_LOCK_RSA);
526 if (rsa->_method_mod_q == NULL)
528 rsa->_method_mod_q = bn_mont_ctx;
531 CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
534 BN_MONT_CTX_free(bn_mont_ctx);
538 if (!BN_mod(&r1,I,rsa->q,ctx)) goto err;
539 if (!rsa->meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx,
540 rsa->_method_mod_q)) goto err;
542 if (!BN_mod(&r1,I,rsa->p,ctx)) goto err;
543 if (!rsa->meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx,
544 rsa->_method_mod_p)) goto err;
546 if (!BN_sub(r0,r0,&m1)) goto err;
547 /* This will help stop the size of r0 increasing, which does
548 * affect the multiply if it optimised for a power of 2 size */
550 if (!BN_add(r0,r0,rsa->p)) goto err;
552 if (!BN_mul(&r1,r0,rsa->iqmp,ctx)) goto err;
553 if (!BN_mod(r0,&r1,rsa->p,ctx)) goto err;
554 /* If p < q it is occasionally possible for the correction of
555 * adding 'p' if r0 is negative above to leave the result still
556 * negative. This can break the private key operations: the following
557 * second correction should *always* correct this rare occurrence.
558 * This will *never* happen with OpenSSL generated keys because
559 * they ensure p > q [steve]
562 if (!BN_add(r0,r0,rsa->p)) goto err;
563 if (!BN_mul(&r1,r0,rsa->q,ctx)) goto err;
564 if (!BN_add(r0,&r1,&m1)) goto err;
566 if (rsa->e && rsa->n)
568 if (!rsa->meth->bn_mod_exp(&vrfy,r0,rsa->e,rsa->n,ctx,NULL)) goto err;
569 /* If 'I' was greater than (or equal to) rsa->n, the operation
570 * will be equivalent to using 'I mod n'. However, the result of
571 * the verify will *always* be less than 'n' so we don't check
572 * for absolute equality, just congruency. */
573 if (!BN_sub(&vrfy, &vrfy, I)) goto err;
574 if (!BN_mod(&vrfy, &vrfy, rsa->n, ctx)) goto err;
576 if (!BN_add(&vrfy, &vrfy, rsa->n)) goto err;
577 if (!BN_is_zero(&vrfy))
578 /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
579 * miscalculated CRT output, just do a raw (slower)
580 * mod_exp and return that instead. */
581 if (!rsa->meth->bn_mod_exp(r0,I,rsa->d,rsa->n,ctx,NULL)) goto err;
587 BN_clear_free(&vrfy);
592 static int RSA_eay_init(RSA *rsa)
594 rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
598 static int RSA_eay_finish(RSA *rsa)
600 if (rsa->_method_mod_n != NULL)
601 BN_MONT_CTX_free(rsa->_method_mod_n);
602 if (rsa->_method_mod_p != NULL)
603 BN_MONT_CTX_free(rsa->_method_mod_p);
604 if (rsa->_method_mod_q != NULL)
605 BN_MONT_CTX_free(rsa->_method_mod_q);