ref: dc96f164a2b72ccb209ae98ce50a11087cbe44f8
dir: /sys/src/ape/lib/openssl/crypto/rsa/rsa_gen.c/
/* crypto/rsa/rsa_gen.c */
/* Copyright (C) 1995-1998 Eric Young ([email protected])
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young ([email protected]).
* 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 ([email protected]).
*
* 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 ([email protected])"
* 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 ([email protected])"
*
* 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.]
*/
/* NB: these functions have been "upgraded", the deprecated versions (which are
* compatibility wrappers using these functions) are in rsa_depr.c.
* - Geoff
*/
#include <stdio.h>
#include <time.h>
#include "cryptlib.h"
#include <openssl/bn.h>
#include <openssl/rsa.h>
static int rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb);
/* NB: this wrapper would normally be placed in rsa_lib.c and the static
* implementation would probably be in rsa_eay.c. Nonetheless, is kept here so
* that we don't introduce a new linker dependency. Eg. any application that
* wasn't previously linking object code related to key-generation won't have to
* now just because key-generation is part of RSA_METHOD. */
int RSA_generate_key_ex(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)
{
if(rsa->meth->rsa_keygen)
return rsa->meth->rsa_keygen(rsa, bits, e_value, cb);
return rsa_builtin_keygen(rsa, bits, e_value, cb);
}
static int rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)
{
BIGNUM *r0=NULL,*r1=NULL,*r2=NULL,*r3=NULL,*tmp;
BIGNUM local_r0,local_d,local_p;
BIGNUM *pr0,*d,*p;
int bitsp,bitsq,ok= -1,n=0;
BN_CTX *ctx=NULL;
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
BN_CTX_start(ctx);
r0 = BN_CTX_get(ctx);
r1 = BN_CTX_get(ctx);
r2 = BN_CTX_get(ctx);
r3 = BN_CTX_get(ctx);
if (r3 == NULL) goto err;
bitsp=(bits+1)/2;
bitsq=bits-bitsp;
/* We need the RSA components non-NULL */
if(!rsa->n && ((rsa->n=BN_new()) == NULL)) goto err;
if(!rsa->d && ((rsa->d=BN_new()) == NULL)) goto err;
if(!rsa->e && ((rsa->e=BN_new()) == NULL)) goto err;
if(!rsa->p && ((rsa->p=BN_new()) == NULL)) goto err;
if(!rsa->q && ((rsa->q=BN_new()) == NULL)) goto err;
if(!rsa->dmp1 && ((rsa->dmp1=BN_new()) == NULL)) goto err;
if(!rsa->dmq1 && ((rsa->dmq1=BN_new()) == NULL)) goto err;
if(!rsa->iqmp && ((rsa->iqmp=BN_new()) == NULL)) goto err;
BN_copy(rsa->e, e_value);
/* generate p and q */
for (;;)
{
if(!BN_generate_prime_ex(rsa->p, bitsp, 0, NULL, NULL, cb))
goto err;
if (!BN_sub(r2,rsa->p,BN_value_one())) goto err;
if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
if (BN_is_one(r1)) break;
if(!BN_GENCB_call(cb, 2, n++))
goto err;
}
if(!BN_GENCB_call(cb, 3, 0))
goto err;
for (;;)
{
/* When generating ridiculously small keys, we can get stuck
* continually regenerating the same prime values. Check for
* this and bail if it happens 3 times. */
unsigned int degenerate = 0;
do
{
if(!BN_generate_prime_ex(rsa->q, bitsq, 0, NULL, NULL, cb))
goto err;
} while((BN_cmp(rsa->p, rsa->q) == 0) && (++degenerate < 3));
if(degenerate == 3)
{
ok = 0; /* we set our own err */
RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,RSA_R_KEY_SIZE_TOO_SMALL);
goto err;
}
if (!BN_sub(r2,rsa->q,BN_value_one())) goto err;
if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
if (BN_is_one(r1))
break;
if(!BN_GENCB_call(cb, 2, n++))
goto err;
}
if(!BN_GENCB_call(cb, 3, 1))
goto err;
if (BN_cmp(rsa->p,rsa->q) < 0)
{
tmp=rsa->p;
rsa->p=rsa->q;
rsa->q=tmp;
}
/* calculate n */
if (!BN_mul(rsa->n,rsa->p,rsa->q,ctx)) goto err;
/* calculate d */
if (!BN_sub(r1,rsa->p,BN_value_one())) goto err; /* p-1 */
if (!BN_sub(r2,rsa->q,BN_value_one())) goto err; /* q-1 */
if (!BN_mul(r0,r1,r2,ctx)) goto err; /* (p-1)(q-1) */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
pr0 = &local_r0;
BN_with_flags(pr0, r0, BN_FLG_CONSTTIME);
}
else
pr0 = r0;
if (!BN_mod_inverse(rsa->d,rsa->e,pr0,ctx)) goto err; /* d */
/* set up d for correct BN_FLG_CONSTTIME flag */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
d = &local_d;
BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
}
else
d = rsa->d;
/* calculate d mod (p-1) */
if (!BN_mod(rsa->dmp1,d,r1,ctx)) goto err;
/* calculate d mod (q-1) */
if (!BN_mod(rsa->dmq1,d,r2,ctx)) goto err;
/* calculate inverse of q mod p */
if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
{
p = &local_p;
BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
}
else
p = rsa->p;
if (!BN_mod_inverse(rsa->iqmp,rsa->q,p,ctx)) goto err;
ok=1;
err:
if (ok == -1)
{
RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,ERR_LIB_BN);
ok=0;
}
if (ctx != NULL)
{
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
return ok;
}