/* crypto/engine/e_gmp.c */
/* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
* project 2003.
*/
/* ====================================================================
* Copyright (c) 1999-2001 The OpenSSL Project. All rights reserved.
*
* 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 above 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 acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* licensing@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED 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 OpenSSL PROJECT OR
* ITS 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.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
/* This engine is not (currently) compiled in by default. Do enable it,
* reconfigure OpenSSL with "enable-gmp -lgmp". The GMP libraries and
* headers must reside in one of the paths searched by the compiler/linker,
* otherwise paths must be specified - eg. try configuring with
* "enable-gmp -I<includepath> -L<libpath> -lgmp". YMMV. */
/* As for what this does - it's a largely unoptimised implementation of an
* ENGINE that uses the GMP library to perform RSA private key operations. To
* obtain more information about what "unoptimised" means, see my original mail
* on the subject (though ignore the build instructions which have since
* changed);
*
* http://www.mail-archive.com/openssl-dev@openssl.org/msg12227.html
*
* On my athlon system at least, it appears the builtin OpenSSL code is now
* slightly faster, which is to say that the RSA-related MPI performance
* between OpenSSL's BIGNUM and GMP's mpz implementations is probably pretty
* balanced for this chip, and so the performance degradation in this ENGINE by
* having to convert to/from GMP formats (and not being able to cache
* montgomery forms) is probably the difference. However, if some unconfirmed
* reports from users is anything to go by, the situation on some other
* chipsets might be a good deal more favourable to the GMP version (eg. PPC).
* Feedback welcome. */
#include <stdio.h>
#include <string.h>
#include <openssl/crypto.h>
#include <openssl/buffer.h>
#include <openssl/engine.h>
#ifndef OPENSSL_NO_RSA
#include <openssl/rsa.h>
#endif
#include <openssl/bn.h>
#ifndef OPENSSL_NO_HW
#ifndef OPENSSL_NO_GMP
#include <gmp.h>
#define E_GMP_LIB_NAME "gmp engine"
#include "e_gmp_err.c"
static int e_gmp_destroy(ENGINE *e);
static int e_gmp_init(ENGINE *e);
static int e_gmp_finish(ENGINE *e);
static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
#ifndef OPENSSL_NO_RSA
/* RSA stuff */
static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa, BN_CTX *ctx);
static int e_gmp_rsa_finish(RSA *r);
#endif
/* The definitions for control commands specific to this engine */
/* #define E_GMP_CMD_SO_PATH ENGINE_CMD_BASE */
static const ENGINE_CMD_DEFN e_gmp_cmd_defns[] = {
#if 0
{E_GMP_CMD_SO_PATH,
"SO_PATH",
"Specifies the path to the 'e_gmp' shared library",
ENGINE_CMD_FLAG_STRING},
#endif
{0, NULL, NULL, 0}
};
#ifndef OPENSSL_NO_RSA
/* Our internal RSA_METHOD that we provide pointers to */
static RSA_METHOD e_gmp_rsa =
{
"GMP RSA method",
NULL,
NULL,
NULL,
NULL,
e_gmp_rsa_mod_exp,
NULL,
NULL,
e_gmp_rsa_finish,
/* These flags initialise montgomery crud that GMP ignores, however it
* makes sure the public key ops (which are done in openssl) don't seem
* *slower* than usual :-) */
RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE,
NULL,
NULL,
NULL
};
#endif
/* Constants used when creating the ENGINE */
static const char *engine_e_gmp_id = "gmp";
static const char *engine_e_gmp_name = "GMP engine support";
/* This internal function is used by ENGINE_gmp() and possibly by the
* "dynamic" ENGINE support too */
static int bind_helper(ENGINE *e)
{
#ifndef OPENSSL_NO_RSA
const RSA_METHOD *meth1;
#endif
if(!ENGINE_set_id(e, engine_e_gmp_id) ||
!ENGINE_set_name(e, engine_e_gmp_name) ||
#ifndef OPENSSL_NO_RSA
!ENGINE_set_RSA(e, &e_gmp_rsa) ||
#endif
!ENGINE_set_destroy_function(e, e_gmp_destroy) ||
!ENGINE_set_init_function(e, e_gmp_init) ||
!ENGINE_set_finish_function(e, e_gmp_finish) ||
!ENGINE_set_ctrl_function(e, e_gmp_ctrl) ||
!ENGINE_set_cmd_defns(e, e_gmp_cmd_defns))
return 0;
#ifndef OPENSSL_NO_RSA
meth1 = RSA_PKCS1_SSLeay();
e_gmp_rsa.rsa_pub_enc = meth1->rsa_pub_enc;
e_gmp_rsa.rsa_pub_dec = meth1->rsa_pub_dec;
e_gmp_rsa.rsa_priv_enc = meth1->rsa_priv_enc;
e_gmp_rsa.rsa_priv_dec = meth1->rsa_priv_dec;
e_gmp_rsa.bn_mod_exp = meth1->bn_mod_exp;
#endif
/* Ensure the e_gmp error handling is set up */
ERR_load_GMP_strings();
return 1;
}
static ENGINE *engine_gmp(void)
{
ENGINE *ret = ENGINE_new();
if(!ret)
return NULL;
if(!bind_helper(ret))
{
ENGINE_free(ret);
return NULL;
}
return ret;
}
void ENGINE_load_gmp(void)
{
/* Copied from eng_[openssl|dyn].c */
ENGINE *toadd = engine_gmp();
if(!toadd) return;
ENGINE_add(toadd);
ENGINE_free(toadd);
ERR_clear_error();
}
#ifndef OPENSSL_NO_RSA
/* Used to attach our own key-data to an RSA structure */
static int hndidx_rsa = -1;
#endif
static int e_gmp_destroy(ENGINE *e)
{
ERR_unload_GMP_strings();
return 1;
}
/* (de)initialisation functions. */
static int e_gmp_init(ENGINE *e)
{
#ifndef OPENSSL_NO_RSA
if (hndidx_rsa == -1)
hndidx_rsa = RSA_get_ex_new_index(0,
"GMP-based RSA key handle",
NULL, NULL, NULL);
#endif
if (hndidx_rsa == -1)
return 0;
return 1;
}
static int e_gmp_finish(ENGINE *e)
{
return 1;
}
static int e_gmp_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void))
{
int to_return = 1;
switch(cmd)
{
#if 0
case E_GMP_CMD_SO_PATH:
/* ... */
#endif
/* The command isn't understood by this engine */
default:
GMPerr(GMP_F_E_GMP_CTRL,
GMP_R_CTRL_COMMAND_NOT_IMPLEMENTED);
to_return = 0;
break;
}
return to_return;
}
/* Most often limb sizes will be the same. If not, we use hex conversion
* which is neat, but extremely inefficient. */
static int bn2gmp(const BIGNUM *bn, mpz_t g)
{
bn_check_top(bn);
if(((sizeof(bn->d[0]) * 8) == GMP_NUMB_BITS) &&
(BN_BITS2 == GMP_NUMB_BITS))
{
/* The common case */
if(!_mpz_realloc (g, bn->top))
return 0;
memcpy(&g->_mp_d[0], &bn->d[0], bn->top * sizeof(bn->d[0]));
g->_mp_size = bn->top;
if(bn->neg)
g->_mp_size = -g->_mp_size;
return 1;
}
else
{
int toret;
char *tmpchar = BN_bn2hex(bn);
if(!tmpchar) return 0;
toret = (mpz_set_str(g, tmpchar, 16) == 0 ? 1 : 0);
OPENSSL_free(tmpchar);
return toret;
}
}
static int gmp2bn(mpz_t g, BIGNUM *bn)
{
if(((sizeof(bn->d[0]) * 8) == GMP_NUMB_BITS) &&
(BN_BITS2 == GMP_NUMB_BITS))
{
/* The common case */
int s = (g->_mp_size >= 0) ? g->_mp_size : -g->_mp_size;
BN_zero(bn);
if(bn_expand2 (bn, s) == NULL)
return 0;
bn->top = s;
memcpy(&bn->d[0], &g->_mp_d[0], s * sizeof(bn->d[0]));
bn_correct_top(bn);
bn->neg = g->_mp_size >= 0 ? 0 : 1;
return 1;
}
else
{
int toret;
char *tmpchar = OPENSSL_malloc(mpz_sizeinbase(g, 16) + 10);
if(!tmpchar) return 0;
mpz_get_str(tmpchar, 16, g);
toret = BN_hex2bn(&bn, tmpchar);
OPENSSL_free(tmpchar);
return toret;
}
}
#ifndef OPENSSL_NO_RSA
typedef struct st_e_gmp_rsa_ctx
{
int public_only;
mpz_t n;
mpz_t d;
mpz_t e;
mpz_t p;
mpz_t q;
mpz_t dmp1;
mpz_t dmq1;
mpz_t iqmp;
mpz_t r0, r1, I0, m1;
} E_GMP_RSA_CTX;
static E_GMP_RSA_CTX *e_gmp_get_rsa(RSA *rsa)
{
E_GMP_RSA_CTX *hptr = RSA_get_ex_data(rsa, hndidx_rsa);
if(hptr) return hptr;
hptr = OPENSSL_malloc(sizeof(E_GMP_RSA_CTX));
if(!hptr) return NULL;
/* These inits could probably be replaced by more intelligent
* mpz_init2() versions, to reduce malloc-thrashing. */
mpz_init(hptr->n);
mpz_init(hptr->d);
mpz_init(hptr->e);
mpz_init(hptr->p);
mpz_init(hptr->q);
mpz_init(hptr->dmp1);
mpz_init(hptr->dmq1);
mpz_init(hptr->iqmp);
mpz_init(hptr->r0);
mpz_init(hptr->r1);
mpz_init(hptr->I0);
mpz_init(hptr->m1);
if(!bn2gmp(rsa->n, hptr->n) || !bn2gmp(rsa->e, hptr->e))
goto err;
if(!rsa->p || !rsa->q || !rsa->d || !rsa->dmp1 || !rsa->dmq1 || !rsa->iqmp)
{
hptr->public_only = 1;
return hptr;
}
if(!bn2gmp(rsa->d, hptr->d) || !bn2gmp(rsa->p, hptr->p) ||
!bn2gmp(rsa->q, hptr->q) || !bn2gmp(rsa->dmp1, hptr->dmp1) ||
!bn2gmp(rsa->dmq1, hptr->dmq1) || !bn2gmp(rsa->iqmp, hptr->iqmp))
goto err;
hptr->public_only = 0;
RSA_set_ex_data(rsa, hndidx_rsa, hptr);
return hptr;
err:
mpz_clear(hptr->n);
mpz_clear(hptr->d);
mpz_clear(hptr->e);
mpz_clear(hptr->p);
mpz_clear(hptr->q);
mpz_clear(hptr->dmp1);
mpz_clear(hptr->dmq1);
mpz_clear(hptr->iqmp);
mpz_clear(hptr->r0);
mpz_clear(hptr->r1);
mpz_clear(hptr->I0);
mpz_clear(hptr->m1);
OPENSSL_free(hptr);
return NULL;
}
static int e_gmp_rsa_finish(RSA *rsa)
{
E_GMP_RSA_CTX *hptr = RSA_get_ex_data(rsa, hndidx_rsa);
if(!hptr) return 0;
mpz_clear(hptr->n);
mpz_clear(hptr->d);
mpz_clear(hptr->e);
mpz_clear(hptr->p);
mpz_clear(hptr->q);
mpz_clear(hptr->dmp1);
mpz_clear(hptr->dmq1);
mpz_clear(hptr->iqmp);
mpz_clear(hptr->r0);
mpz_clear(hptr->r1);
mpz_clear(hptr->I0);
mpz_clear(hptr->m1);
OPENSSL_free(hptr);
RSA_set_ex_data(rsa, hndidx_rsa, NULL);
return 1;
}
static int e_gmp_rsa_mod_exp(BIGNUM *r, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
{
E_GMP_RSA_CTX *hptr;
int to_return = 0;
hptr = e_gmp_get_rsa(rsa);
if(!hptr)
{
GMPerr(GMP_F_E_GMP_RSA_MOD_EXP,
GMP_R_KEY_CONTEXT_ERROR);
return 0;
}
if(hptr->public_only)
{
GMPerr(GMP_F_E_GMP_RSA_MOD_EXP,
GMP_R_MISSING_KEY_COMPONENTS);
return 0;
}
/* ugh!!! */
if(!bn2gmp(I, hptr->I0))
return 0;
/* This is basically the CRT logic in crypto/rsa/rsa_eay.c reworded into
* GMP-speak. It may be that GMP's API facilitates cleaner formulations
* of this stuff, eg. better handling of negatives, or functions that
* combine operations. */
mpz_mod(hptr->r1, hptr->I0, hptr->q);
mpz_powm(hptr->m1, hptr->r1, hptr->dmq1, hptr->q);
mpz_mod(hptr->r1, hptr->I0, hptr->p);
mpz_powm(hptr->r0, hptr->r1, hptr->dmp1, hptr->p);
mpz_sub(hptr->r0, hptr->r0, hptr->m1);
if(mpz_sgn(hptr->r0) < 0)
mpz_add(hptr->r0, hptr->r0, hptr->p);
mpz_mul(hptr->r1, hptr->r0, hptr->iqmp);
mpz_mod(hptr->r0, hptr->r1, hptr->p);
if(mpz_sgn(hptr->r0) < 0)
mpz_add(hptr->r0, hptr->r0, hptr->p);
mpz_mul(hptr->r1, hptr->r0, hptr->q);
mpz_add(hptr->r0, hptr->r1, hptr->m1);
/* ugh!!! */
if(gmp2bn(hptr->r0, r))
to_return = 1;
return 1;
}
#endif
#endif /* !OPENSSL_NO_GMP */
/* This stuff is needed if this ENGINE is being compiled into a self-contained
* shared-library. */
#ifndef OPENSSL_NO_DYNAMIC_ENGINE
IMPLEMENT_DYNAMIC_CHECK_FN()
#ifndef OPENSSL_NO_GMP
static int bind_fn(ENGINE *e, const char *id)
{
if(id && (strcmp(id, engine_e_gmp_id) != 0))
return 0;
if(!bind_helper(e))
return 0;
return 1;
}
IMPLEMENT_DYNAMIC_BIND_FN(bind_fn)
#else
OPENSSL_EXPORT
int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns);
OPENSSL_EXPORT
int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns) { return 0; }
#endif
#endif /* !OPENSSL_NO_DYNAMIC_ENGINE */
#endif /* !OPENSSL_NO_HW */
