openssl/crypto/rsa/rsa_eay.c

490 lines
13 KiB
C

/* crypto/rsa/rsa_eay.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <stdio.h>
#include "cryptlib.h"
#include <openssl/bn.h>
#include <openssl/rsa.h>
#include <openssl/rand.h>
static int RSA_eay_public_encrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa,int padding);
static int RSA_eay_private_encrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa,int padding);
static int RSA_eay_public_decrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa,int padding);
static int RSA_eay_private_decrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa,int padding);
static int RSA_eay_mod_exp(BIGNUM *r0, BIGNUM *i, RSA *rsa);
static int RSA_eay_init(RSA *rsa);
static int RSA_eay_finish(RSA *rsa);
static RSA_METHOD rsa_pkcs1_eay_meth={
"Eric Young's PKCS#1 RSA",
RSA_eay_public_encrypt,
RSA_eay_public_decrypt,
RSA_eay_private_encrypt,
RSA_eay_private_decrypt,
RSA_eay_mod_exp,
BN_mod_exp_mont,
RSA_eay_init,
RSA_eay_finish,
0,
NULL,
};
RSA_METHOD *RSA_PKCS1_SSLeay(void)
{
return(&rsa_pkcs1_eay_meth);
}
static int RSA_eay_public_encrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa, int padding)
{
BIGNUM f,ret;
int i,j,k,num=0,r= -1;
unsigned char *buf=NULL;
BN_CTX *ctx=NULL;
BN_init(&f);
BN_init(&ret);
if ((ctx=BN_CTX_new()) == NULL) goto err;
num=BN_num_bytes(rsa->n);
if ((buf=(unsigned char *)Malloc(num)) == NULL)
{
RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
goto err;
}
switch (padding)
{
case RSA_PKCS1_PADDING:
i=RSA_padding_add_PKCS1_type_2(buf,num,from,flen);
break;
#ifndef NO_SHA
case RSA_PKCS1_OAEP_PADDING:
i=RSA_padding_add_PKCS1_OAEP(buf,num,from,flen,NULL,0);
break;
#endif
case RSA_SSLV23_PADDING:
i=RSA_padding_add_SSLv23(buf,num,from,flen);
break;
case RSA_NO_PADDING:
i=RSA_padding_add_none(buf,num,from,flen);
break;
default:
RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
goto err;
}
if (i <= 0) goto err;
if (BN_bin2bn(buf,num,&f) == NULL) goto err;
if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
{
if ((rsa->_method_mod_n=BN_MONT_CTX_new()) != NULL)
if (!BN_MONT_CTX_set(rsa->_method_mod_n,rsa->n,ctx))
goto err;
}
if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
rsa->_method_mod_n)) goto err;
/* put in leading 0 bytes if the number is less than the
* length of the modulus */
j=BN_num_bytes(&ret);
i=BN_bn2bin(&ret,&(to[num-j]));
for (k=0; k<(num-i); k++)
to[k]=0;
r=num;
err:
if (ctx != NULL) BN_CTX_free(ctx);
BN_clear_free(&f);
BN_clear_free(&ret);
if (buf != NULL)
{
memset(buf,0,num);
Free(buf);
}
return(r);
}
static int RSA_eay_private_encrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa, int padding)
{
BIGNUM f,ret;
int i,j,k,num=0,r= -1;
unsigned char *buf=NULL;
BN_CTX *ctx=NULL;
BN_init(&f);
BN_init(&ret);
if ((ctx=BN_CTX_new()) == NULL) goto err;
num=BN_num_bytes(rsa->n);
if ((buf=(unsigned char *)Malloc(num)) == NULL)
{
RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
goto err;
}
switch (padding)
{
case RSA_PKCS1_PADDING:
i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
break;
case RSA_NO_PADDING:
i=RSA_padding_add_none(buf,num,from,flen);
break;
case RSA_SSLV23_PADDING:
default:
RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
goto err;
}
if (i <= 0) goto err;
if (BN_bin2bn(buf,num,&f) == NULL) goto err;
if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
RSA_blinding_on(rsa,ctx);
if (rsa->flags & RSA_FLAG_BLINDING)
if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
((rsa->p != NULL) &&
(rsa->q != NULL) &&
(rsa->dmp1 != NULL) &&
(rsa->dmq1 != NULL) &&
(rsa->iqmp != NULL)) )
{ if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
else
{
if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL)) goto err;
}
if (rsa->flags & RSA_FLAG_BLINDING)
if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err;
/* put in leading 0 bytes if the number is less than the
* length of the modulus */
j=BN_num_bytes(&ret);
i=BN_bn2bin(&ret,&(to[num-j]));
for (k=0; k<(num-i); k++)
to[k]=0;
r=num;
err:
if (ctx != NULL) BN_CTX_free(ctx);
BN_clear_free(&ret);
BN_clear_free(&f);
if (buf != NULL)
{
memset(buf,0,num);
Free(buf);
}
return(r);
}
static int RSA_eay_private_decrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa, int padding)
{
BIGNUM f,ret;
int j,num=0,r= -1;
unsigned char *p;
unsigned char *buf=NULL;
BN_CTX *ctx=NULL;
BN_init(&f);
BN_init(&ret);
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
num=BN_num_bytes(rsa->n);
if ((buf=(unsigned char *)Malloc(num)) == NULL)
{
RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
goto err;
}
/* This check was for equallity but PGP does evil things
* and chops off the top '0' bytes */
if (flen > num)
{
RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
goto err;
}
/* make data into a big number */
if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err;
if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
RSA_blinding_on(rsa,ctx);
if (rsa->flags & RSA_FLAG_BLINDING)
if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
/* do the decrypt */
if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
((rsa->p != NULL) &&
(rsa->q != NULL) &&
(rsa->dmp1 != NULL) &&
(rsa->dmq1 != NULL) &&
(rsa->iqmp != NULL)) )
{ if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err; }
else
{
if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->d,rsa->n,ctx,NULL))
goto err;
}
if (rsa->flags & RSA_FLAG_BLINDING)
if (!BN_BLINDING_invert(&ret,rsa->blinding,ctx)) goto err;
p=buf;
j=BN_bn2bin(&ret,p); /* j is only used with no-padding mode */
switch (padding)
{
case RSA_PKCS1_PADDING:
r=RSA_padding_check_PKCS1_type_2(to,num,buf,j,num);
break;
#ifndef NO_SHA
case RSA_PKCS1_OAEP_PADDING:
r=RSA_padding_check_PKCS1_OAEP(to,num,buf,j,num,NULL,0);
break;
#endif
case RSA_SSLV23_PADDING:
r=RSA_padding_check_SSLv23(to,num,buf,j,num);
break;
case RSA_NO_PADDING:
r=RSA_padding_check_none(to,num,buf,j,num);
break;
default:
RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
goto err;
}
if (r < 0)
RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
err:
if (ctx != NULL) BN_CTX_free(ctx);
BN_clear_free(&f);
BN_clear_free(&ret);
if (buf != NULL)
{
memset(buf,0,num);
Free(buf);
}
return(r);
}
static int RSA_eay_public_decrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa, int padding)
{
BIGNUM f,ret;
int i,num=0,r= -1;
unsigned char *p;
unsigned char *buf=NULL;
BN_CTX *ctx=NULL;
BN_init(&f);
BN_init(&ret);
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
num=BN_num_bytes(rsa->n);
buf=(unsigned char *)Malloc(num);
if (buf == NULL)
{
RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
goto err;
}
/* This check was for equallity but PGP does evil things
* and chops off the top '0' bytes */
if (flen > num)
{
RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_GREATER_THAN_MOD_LEN);
goto err;
}
if (BN_bin2bn(from,flen,&f) == NULL) goto err;
/* do the decrypt */
if ((rsa->_method_mod_n == NULL) && (rsa->flags & RSA_FLAG_CACHE_PUBLIC))
{
if ((rsa->_method_mod_n=BN_MONT_CTX_new()) != NULL)
if (!BN_MONT_CTX_set(rsa->_method_mod_n,rsa->n,ctx))
goto err;
}
if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
rsa->_method_mod_n)) goto err;
p=buf;
i=BN_bn2bin(&ret,p);
switch (padding)
{
case RSA_PKCS1_PADDING:
r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
break;
case RSA_NO_PADDING:
r=RSA_padding_check_none(to,num,buf,i,num);
break;
default:
RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_UNKNOWN_PADDING_TYPE);
goto err;
}
if (r < 0)
RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
err:
if (ctx != NULL) BN_CTX_free(ctx);
BN_clear_free(&f);
BN_clear_free(&ret);
if (buf != NULL)
{
memset(buf,0,num);
Free(buf);
}
return(r);
}
static int RSA_eay_mod_exp(BIGNUM *r0, BIGNUM *I, RSA *rsa)
{
BIGNUM r1,m1;
int ret=0;
BN_CTX *ctx;
if ((ctx=BN_CTX_new()) == NULL) goto err;
BN_init(&m1);
BN_init(&r1);
if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
{
if (rsa->_method_mod_p == NULL)
{
if ((rsa->_method_mod_p=BN_MONT_CTX_new()) != NULL)
if (!BN_MONT_CTX_set(rsa->_method_mod_p,rsa->p,
ctx))
goto err;
}
if (rsa->_method_mod_q == NULL)
{
if ((rsa->_method_mod_q=BN_MONT_CTX_new()) != NULL)
if (!BN_MONT_CTX_set(rsa->_method_mod_q,rsa->q,
ctx))
goto err;
}
}
if (!BN_mod(&r1,I,rsa->q,ctx)) goto err;
if (!rsa->meth->bn_mod_exp(&m1,&r1,rsa->dmq1,rsa->q,ctx,
rsa->_method_mod_q)) goto err;
if (!BN_mod(&r1,I,rsa->p,ctx)) goto err;
if (!rsa->meth->bn_mod_exp(r0,&r1,rsa->dmp1,rsa->p,ctx,
rsa->_method_mod_p)) goto err;
if (!BN_sub(r0,r0,&m1)) goto err;
/* This will help stop the size of r0 increasing, which does
* affect the multiply if it optimised for a power of 2 size */
if (r0->neg)
if (!BN_add(r0,r0,rsa->p)) goto err;
if (!BN_mul(&r1,r0,rsa->iqmp,ctx)) goto err;
if (!BN_mod(r0,&r1,rsa->p,ctx)) goto err;
/* If p < q it is occasionally possible for the correction of
* adding 'p' if r0 is negative above to leave the result still
* negative. This can break the private key operations: the following
* second correction should *always* correct this rare occurrence.
* This will *never* happen with OpenSSL generated keys because
* they ensure p > q [steve]
*/
if (r0->neg)
if (!BN_add(r0,r0,rsa->p)) goto err;
if (!BN_mul(&r1,r0,rsa->q,ctx)) goto err;
if (!BN_add(r0,&r1,&m1)) goto err;
ret=1;
err:
BN_clear_free(&m1);
BN_clear_free(&r1);
BN_CTX_free(ctx);
return(ret);
}
static int RSA_eay_init(RSA *rsa)
{
rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
return(1);
}
static int RSA_eay_finish(RSA *rsa)
{
if (rsa->_method_mod_n != NULL)
BN_MONT_CTX_free(rsa->_method_mod_n);
if (rsa->_method_mod_p != NULL)
BN_MONT_CTX_free(rsa->_method_mod_p);
if (rsa->_method_mod_q != NULL)
BN_MONT_CTX_free(rsa->_method_mod_q);
return(1);
}