openssl/crypto/dsa/dsa_lib.c
Dr. Stephen Henson 31360957fb DH keys have an (until now) unused 'q' parameter. When creating
from DSA copy q across and if q present generate DH key in the
correct range.
2011-04-07 15:01:48 +00:00

316 lines
8.3 KiB
C

/* crypto/dsa/dsa_lib.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.]
*/
/* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
#include <stdio.h>
#include "cryptlib.h"
#include <openssl/bn.h>
#include <openssl/dsa.h>
#include <openssl/asn1.h>
#ifndef OPENSSL_NO_ENGINE
#include <openssl/engine.h>
#endif
#ifndef OPENSSL_NO_DH
#include <openssl/dh.h>
#endif
const char DSA_version[]="DSA" OPENSSL_VERSION_PTEXT;
static const DSA_METHOD *default_DSA_method = NULL;
void DSA_set_default_method(const DSA_METHOD *meth)
{
default_DSA_method = meth;
}
const DSA_METHOD *DSA_get_default_method(void)
{
if(!default_DSA_method)
default_DSA_method = DSA_OpenSSL();
return default_DSA_method;
}
DSA *DSA_new(void)
{
return DSA_new_method(NULL);
}
int DSA_set_method(DSA *dsa, const DSA_METHOD *meth)
{
/* NB: The caller is specifically setting a method, so it's not up to us
* to deal with which ENGINE it comes from. */
const DSA_METHOD *mtmp;
mtmp = dsa->meth;
if (mtmp->finish) mtmp->finish(dsa);
#ifndef OPENSSL_NO_ENGINE
if (dsa->engine)
{
ENGINE_finish(dsa->engine);
dsa->engine = NULL;
}
#endif
dsa->meth = meth;
if (meth->init) meth->init(dsa);
return 1;
}
DSA *DSA_new_method(ENGINE *engine)
{
DSA *ret;
ret=(DSA *)OPENSSL_malloc(sizeof(DSA));
if (ret == NULL)
{
DSAerr(DSA_F_DSA_NEW_METHOD,ERR_R_MALLOC_FAILURE);
return(NULL);
}
ret->meth = DSA_get_default_method();
#ifndef OPENSSL_NO_ENGINE
if (engine)
{
if (!ENGINE_init(engine))
{
DSAerr(DSA_F_DSA_NEW_METHOD, ERR_R_ENGINE_LIB);
OPENSSL_free(ret);
return NULL;
}
ret->engine = engine;
}
else
ret->engine = ENGINE_get_default_DSA();
if(ret->engine)
{
ret->meth = ENGINE_get_DSA(ret->engine);
if(!ret->meth)
{
DSAerr(DSA_F_DSA_NEW_METHOD,
ERR_R_ENGINE_LIB);
ENGINE_finish(ret->engine);
OPENSSL_free(ret);
return NULL;
}
}
#endif
ret->pad=0;
ret->version=0;
ret->write_params=1;
ret->p=NULL;
ret->q=NULL;
ret->g=NULL;
ret->pub_key=NULL;
ret->priv_key=NULL;
ret->kinv=NULL;
ret->r=NULL;
ret->method_mont_p=NULL;
ret->references=1;
ret->flags=ret->meth->flags;
CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
if ((ret->meth->init != NULL) && !ret->meth->init(ret))
{
#ifndef OPENSSL_NO_ENGINE
if (ret->engine)
ENGINE_finish(ret->engine);
#endif
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data);
OPENSSL_free(ret);
ret=NULL;
}
return(ret);
}
void DSA_free(DSA *r)
{
int i;
if (r == NULL) return;
i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_DSA);
#ifdef REF_PRINT
REF_PRINT("DSA",r);
#endif
if (i > 0) return;
#ifdef REF_CHECK
if (i < 0)
{
fprintf(stderr,"DSA_free, bad reference count\n");
abort();
}
#endif
if(r->meth->finish)
r->meth->finish(r);
#ifndef OPENSSL_NO_ENGINE
if(r->engine)
ENGINE_finish(r->engine);
#endif
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, r, &r->ex_data);
if (r->p != NULL) BN_clear_free(r->p);
if (r->q != NULL) BN_clear_free(r->q);
if (r->g != NULL) BN_clear_free(r->g);
if (r->pub_key != NULL) BN_clear_free(r->pub_key);
if (r->priv_key != NULL) BN_clear_free(r->priv_key);
if (r->kinv != NULL) BN_clear_free(r->kinv);
if (r->r != NULL) BN_clear_free(r->r);
OPENSSL_free(r);
}
int DSA_up_ref(DSA *r)
{
int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DSA);
#ifdef REF_PRINT
REF_PRINT("DSA",r);
#endif
#ifdef REF_CHECK
if (i < 2)
{
fprintf(stderr, "DSA_up_ref, bad reference count\n");
abort();
}
#endif
return ((i > 1) ? 1 : 0);
}
int DSA_size(const DSA *r)
{
int ret,i;
ASN1_INTEGER bs;
unsigned char buf[4]; /* 4 bytes looks really small.
However, i2d_ASN1_INTEGER() will not look
beyond the first byte, as long as the second
parameter is NULL. */
i=BN_num_bits(r->q);
bs.length=(i+7)/8;
bs.data=buf;
bs.type=V_ASN1_INTEGER;
/* If the top bit is set the asn1 encoding is 1 larger. */
buf[0]=0xff;
i=i2d_ASN1_INTEGER(&bs,NULL);
i+=i; /* r and s */
ret=ASN1_object_size(1,i,V_ASN1_SEQUENCE);
return(ret);
}
int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
{
return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DSA, argl, argp,
new_func, dup_func, free_func);
}
int DSA_set_ex_data(DSA *d, int idx, void *arg)
{
return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));
}
void *DSA_get_ex_data(DSA *d, int idx)
{
return(CRYPTO_get_ex_data(&d->ex_data,idx));
}
#ifndef OPENSSL_NO_DH
DH *DSA_dup_DH(const DSA *r)
{
/* DSA has p, q, g, optional pub_key, optional priv_key.
* DH has p, optional length, g, optional pub_key, optional priv_key,
* optional q.
*/
DH *ret = NULL;
if (r == NULL)
goto err;
ret = DH_new();
if (ret == NULL)
goto err;
if (r->p != NULL)
if ((ret->p = BN_dup(r->p)) == NULL)
goto err;
if (r->q != NULL)
{
ret->length = BN_num_bits(r->q);
if ((ret->q = BN_dup(r->q)) == NULL)
goto err;
}
if (r->g != NULL)
if ((ret->g = BN_dup(r->g)) == NULL)
goto err;
if (r->pub_key != NULL)
if ((ret->pub_key = BN_dup(r->pub_key)) == NULL)
goto err;
if (r->priv_key != NULL)
if ((ret->priv_key = BN_dup(r->priv_key)) == NULL)
goto err;
return ret;
err:
if (ret != NULL)
DH_free(ret);
return NULL;
}
#endif