src/parsec/disk-image/parsec/parsec-benchmark/pkgs/libs/ssl/src/engines/e_gmp.c - public/gem5-resources - Git at Google

 /* 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>
 #include <openssl/rsa.h>
 #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) { return 0; }
 #endif
 #endif /* OPENSSL_NO_DYNAMIC_ENGINE */

 #endif /* !OPENSSL_NO_HW */
	/* 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>
	#include <openssl/rsa.h>
	#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) { return 0; }
	#endif
	#endif /* OPENSSL_NO_DYNAMIC_ENGINE */

	#endif /* !OPENSSL_NO_HW */