[thirdparty/openssl.git] / crypto / ec / ecp_nist.c

/* crypto/ec/ecp_nist.c */
/*
 * Written by Nils Larsch for the OpenSSL project.
 */
/* ====================================================================
 * Copyright (c) 1998-2002 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
 *    openssl-core@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).
 *
 */
/* ====================================================================
 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
 * Portions of this software developed by SUN MICROSYSTEMS, INC.,
 * and contributed to the OpenSSL project.
 */

#include <openssl/err.h>
#include <openssl/obj_mac.h>
#include "ec_lcl.h"

const EC_METHOD *EC_GFp_nist_method(void)
	{
	static const EC_METHOD ret = {
		NID_X9_62_prime_field,
		ec_GFp_nist_group_init,
		ec_GFp_nist_group_finish,
		ec_GFp_nist_group_clear_finish,
		ec_GFp_nist_group_copy,
		ec_GFp_nist_group_set_curve,
		ec_GFp_simple_group_get_curve,
		ec_GFp_simple_group_get_degree,
		ec_GFp_simple_group_check_discriminant,
		ec_GFp_simple_point_init,
		ec_GFp_simple_point_finish,
		ec_GFp_simple_point_clear_finish,
		ec_GFp_simple_point_copy,
		ec_GFp_simple_point_set_to_infinity,
		ec_GFp_simple_set_Jprojective_coordinates_GFp,
		ec_GFp_simple_get_Jprojective_coordinates_GFp,
		ec_GFp_simple_point_set_affine_coordinates,
		ec_GFp_simple_point_get_affine_coordinates,
		ec_GFp_simple_set_compressed_coordinates,
		ec_GFp_simple_point2oct,
		ec_GFp_simple_oct2point,
		ec_GFp_simple_add,
		ec_GFp_simple_dbl,
		ec_GFp_simple_invert,
		0 /* mul */,
		0 /* precompute_mult */,
		ec_GFp_simple_is_at_infinity,
		ec_GFp_simple_is_on_curve,
		ec_GFp_simple_cmp,
		ec_GFp_simple_make_affine,
		ec_GFp_simple_points_make_affine,
		ec_GFp_nist_field_mul,
		ec_GFp_nist_field_sqr,
		0 /* field_div */,
		0 /* field_encode */,
		0 /* field_decode */,
		0 /* field_set_to_one */ };

	return &ret;
	}

#if BN_BITS2 == 64 && UINT_MAX != 4294967295UL && ULONG_MAX != 4294967295UL
#define	NO_32_BIT_TYPE
#endif

int ec_GFp_nist_group_init(EC_GROUP *group)
	{
	int ok;

	ok = ec_GFp_simple_group_init(group);
	group->field_data1 = NULL;
	return ok;
	}

void ec_GFp_nist_group_finish(EC_GROUP *group)
	{
	BN_free(&group->field);
	BN_free(&group->a);
	BN_free(&group->b);
	}


void ec_GFp_nist_group_clear_finish(EC_GROUP *group)
	{
	BN_clear_free(&group->field);
	BN_clear_free(&group->a);
	BN_clear_free(&group->b);
	}


int ec_GFp_nist_group_set_curve(EC_GROUP *group, const BIGNUM *p,
	const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
	{
	int ret = 0;
	BN_CTX *new_ctx = NULL;
	BIGNUM *tmp_bn;
	
	if (ctx == NULL)
		if ((ctx = new_ctx = BN_CTX_new()) == NULL) return 0;

	BN_CTX_start(ctx);
	if ((tmp_bn = BN_CTX_get(ctx)) == NULL) goto err;

	if (BN_ucmp(BN_get0_nist_prime_192(), p) == 0)
		group->field_mod_func = BN_nist_mod_192;
	else if (BN_ucmp(BN_get0_nist_prime_224(), p) == 0)
		{
#if !defined(NO_32_BIT_TYPE) || defined(OPENSSL_NO_ASM)
		group->field_mod_func = BN_nist_mod_224;
#else
		ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE_GFP, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
		goto err;
#endif
		}
	else if (BN_ucmp(BN_get0_nist_prime_256(), p) == 0)
		{
#if !defined(NO_32_BIT_TYPE) || defined(OPENSSL_NO_ASM)
		group->field_mod_func = BN_nist_mod_256;
#else
		ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE_GFP, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
		goto err;
#endif
		}
	else if (BN_ucmp(BN_get0_nist_prime_384(), p) == 0)
		{
#if !defined(NO_32_BIT_TYPE) || defined(OPENSSL_NO_ASM)
		group->field_mod_func = BN_nist_mod_384;
#else
		ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE_GFP, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
		goto err;
#endif
		}
	else if (BN_ucmp(BN_get0_nist_prime_521(), p) == 0)
		/* this one works in the NO_32_BIT_TYPE case */
		group->field_mod_func = BN_nist_mod_521;
	else
		{
		ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE_GFP, EC_R_NOT_A_NIST_PRIME);
		goto err;
		}

	/* group->field */
	if (!BN_copy(&group->field, p)) goto err;
	BN_set_sign(&group->field, 0);

	/* group->a */
	if (!group->field_mod_func(&group->a, a, p, ctx)) goto err;

	/* group->b */
	if (!group->field_mod_func(&group->b, b, p, ctx)) goto err;

	/* group->a_is_minus3 */
	if (!BN_add_word(tmp_bn, 3)) goto err;
	group->a_is_minus3 = (0 == BN_cmp(tmp_bn, &group->field));

	ret = 1;

 err:
	BN_CTX_end(ctx);
	if (new_ctx != NULL)
		BN_CTX_free(new_ctx);
	return ret;
	}

int ec_GFp_nist_group_copy(EC_GROUP *dest, const EC_GROUP *src)
	{
	if (dest == NULL || src == NULL)
		return 0;

	if (!BN_copy(&dest->field, &src->field))
		return 0;
	if (!BN_copy(&dest->a, &src->a))
		return 0;
	if (!BN_copy(&dest->b, &src->b))
		return 0;

	dest->curve_name  = src->curve_name;

	dest->a_is_minus3 = src->a_is_minus3;

	dest->field_data1 = src->field_data1;

	return 1;
	}

int ec_GFp_nist_field_mul(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a,
	const BIGNUM *b, BN_CTX *ctx)
	{
	int	ret=0;
	BN_CTX	*ctx_new=NULL;

	if (!group || !r || !a || !b)
		{
		ECerr(EC_F_EC_GFP_NIST_FIELD_MUL, ERR_R_PASSED_NULL_PARAMETER);
		goto err;
		}
	if (!ctx)
		if ((ctx_new = ctx = BN_CTX_new()) == NULL) goto err;

	if (!BN_mul(r, a, b, ctx)) goto err;
	if (!group->field_mod_func(r, r, &group->field, ctx))
		goto err;

	ret=1;
err:
	if (ctx_new)
		BN_CTX_free(ctx_new);
	return ret;
	}

int ec_GFp_nist_field_sqr(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a,
	BN_CTX *ctx)
	{
	int	ret=0;
	BN_CTX	*ctx_new=NULL;

	if (!group || !r || !a)
		{
		ECerr(EC_F_EC_GFP_NIST_FIELD_SQR, EC_R_PASSED_NULL_PARAMETER);
		goto err;
		}
	if (!ctx)
		if ((ctx_new = ctx = BN_CTX_new()) == NULL) goto err;

	if (!BN_sqr(r, a, ctx)) goto err;
	if (!group->field_mod_func(r, r, &group->field, ctx))
		goto err;

	ret=1;
err:
	if (ctx_new)
		BN_CTX_free(ctx_new);
	return ret;
	}
Commit	Line	Data
38e3c581	1	/* crypto/ec/ecp_nist.c */
5c6bf031 BM	2	/*
	3	* Written by Nils Larsch for the OpenSSL project.
	4	*/
38e3c581	5	/* ====================================================================
5c6bf031	6	* Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
38e3c581 BM	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	11	*
	12	* 1. Redistributions of source code must retain the above copyright
	13	* notice, this list of conditions and the following disclaimer.
	14	*
	15	* 2. Redistributions in binary form must reproduce the above copyright
	16	* notice, this list of conditions and the following disclaimer in
	17	* the documentation and/or other materials provided with the
	18	* distribution.
	19	*
	20	* 3. All advertising materials mentioning features or use of this
	21	* software must display the following acknowledgment:
	22	* "This product includes software developed by the OpenSSL Project
	23	* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
	24	*
	25	* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
	26	* endorse or promote products derived from this software without
	27	* prior written permission. For written permission, please contact
	28	* openssl-core@openssl.org.
	29	*
	30	* 5. Products derived from this software may not be called "OpenSSL"
	31	* nor may "OpenSSL" appear in their names without prior written
	32	* permission of the OpenSSL Project.
	33	*
	34	* 6. Redistributions of any form whatsoever must retain the following
	35	* acknowledgment:
	36	* "This product includes software developed by the OpenSSL Project
	37	* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
	38	*
	39	* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
	40	* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	41	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	42	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
	43	* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	44	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	45	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	46	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	47	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	48	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	49	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
	50	* OF THE POSSIBILITY OF SUCH DAMAGE.
	51	* ====================================================================
	52	*
	53	* This product includes cryptographic software written by Eric Young
	54	* (eay@cryptsoft.com). This product includes software written by Tim
	55	* Hudson (tjh@cryptsoft.com).
	56	*
	57	*/
7793f30e BM	58	/* ====================================================================
	59	* Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
	60	* Portions of this software developed by SUN MICROSYSTEMS, INC.,
	61	* and contributed to the OpenSSL project.
	62	*/
38e3c581	63
5c6bf031 BM	64	#include <openssl/err.h>
5c6bf031 BM	65	#include <openssl/obj_mac.h>
38e3c581	66	#include "ec_lcl.h"
0657bf9c	67
0657bf9c BM	68	const EC_METHOD *EC_GFp_nist_method(void)
0657bf9c BM	69	{
58fc6229	70	static const EC_METHOD ret = {
5c6bf031	71	NID_X9_62_prime_field,
f1f25544	72	ec_GFp_nist_group_init,
2e0db076 BM	73	ec_GFp_nist_group_finish,
2e0db076 BM	74	ec_GFp_nist_group_clear_finish,
60428dbf	75	ec_GFp_nist_group_copy,
35b73a1f BM	76	ec_GFp_nist_group_set_curve,
35b73a1f BM	77	ec_GFp_simple_group_get_curve,
7793f30e	78	ec_GFp_simple_group_get_degree,
17d6bb81	79	ec_GFp_simple_group_check_discriminant,
58fc6229 BM	80	ec_GFp_simple_point_init,
	81	ec_GFp_simple_point_finish,
	82	ec_GFp_simple_point_clear_finish,
	83	ec_GFp_simple_point_copy,
226cc7de	84	ec_GFp_simple_point_set_to_infinity,
1d5bd6cf BM	85	ec_GFp_simple_set_Jprojective_coordinates_GFp,
1d5bd6cf BM	86	ec_GFp_simple_get_Jprojective_coordinates_GFp,
35b73a1f BM	87	ec_GFp_simple_point_set_affine_coordinates,
	88	ec_GFp_simple_point_get_affine_coordinates,
	89	ec_GFp_simple_set_compressed_coordinates,
58fc6229 BM	90	ec_GFp_simple_point2oct,
	91	ec_GFp_simple_oct2point,
	92	ec_GFp_simple_add,
	93	ec_GFp_simple_dbl,
1d5bd6cf	94	ec_GFp_simple_invert,
7793f30e BM	95	0 /* mul */,
7793f30e BM	96	0 /* precompute_mult */,
58fc6229 BM	97	ec_GFp_simple_is_at_infinity,
58fc6229 BM	98	ec_GFp_simple_is_on_curve,
1d5bd6cf	99	ec_GFp_simple_cmp,
58fc6229	100	ec_GFp_simple_make_affine,
48fe4d62	101	ec_GFp_simple_points_make_affine,
60428dbf	102	ec_GFp_nist_field_mul,
58fc6229	103	ec_GFp_nist_field_sqr,
7793f30e	104	0 /* field_div */,
156e8557	105	0 /* field_encode */,
48fe4d62 BM	106	0 /* field_decode */,
48fe4d62 BM	107	0 /* field_set_to_one */ };
0657bf9c BM	108
	109	return &ret;
	110	}
60428dbf	111
5c6bf031 BM	112	#if BN_BITS2 == 64 && UINT_MAX != 4294967295UL && ULONG_MAX != 4294967295UL
	113	#define NO_32_BIT_TYPE
	114	#endif
60428dbf BM	115
	116	int ec_GFp_nist_group_init(EC_GROUP *group)
	117	{
	118	int ok;
	119
	120	ok = ec_GFp_simple_group_init(group);
48fe4d62	121	group->field_data1 = NULL;
60428dbf BM	122	return ok;
	123	}
	124
5c6bf031 BM	125	void ec_GFp_nist_group_finish(EC_GROUP *group)
	126	{
	127	BN_free(&group->field);
	128	BN_free(&group->a);
	129	BN_free(&group->b);
	130	}
	131
	132
	133	void ec_GFp_nist_group_clear_finish(EC_GROUP *group)
	134	{
	135	BN_clear_free(&group->field);
	136	BN_clear_free(&group->a);
	137	BN_clear_free(&group->b);
	138	}
	139
	140
	141	int ec_GFp_nist_group_set_curve(EC_GROUP group, const BIGNUM p,
	142	const BIGNUM a, const BIGNUM b, BN_CTX *ctx)
	143	{
	144	int ret = 0;
	145	BN_CTX *new_ctx = NULL;
	146	BIGNUM *tmp_bn;
	147
	148	if (ctx == NULL)
	149	if ((ctx = new_ctx = BN_CTX_new()) == NULL) return 0;
	150
	151	BN_CTX_start(ctx);
	152	if ((tmp_bn = BN_CTX_get(ctx)) == NULL) goto err;
	153
	154	if (BN_ucmp(BN_get0_nist_prime_192(), p) == 0)
19b8d06a	155	group->field_mod_func = BN_nist_mod_192;
5c6bf031	156	else if (BN_ucmp(BN_get0_nist_prime_224(), p) == 0)
62dd6f16	157	{
19b8d06a BM	158	#if !defined(NO_32_BIT_TYPE) \|\| defined(OPENSSL_NO_ASM)
19b8d06a BM	159	group->field_mod_func = BN_nist_mod_224;
5c6bf031	160	#else
19b8d06a	161	ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE_GFP, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
5c6bf031 BM	162	goto err;
5c6bf031 BM	163	#endif
62dd6f16	164	}
5c6bf031	165	else if (BN_ucmp(BN_get0_nist_prime_256(), p) == 0)
62dd6f16	166	{
19b8d06a BM	167	#if !defined(NO_32_BIT_TYPE) \|\| defined(OPENSSL_NO_ASM)
19b8d06a BM	168	group->field_mod_func = BN_nist_mod_256;
5c6bf031	169	#else
19b8d06a	170	ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE_GFP, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
5c6bf031 BM	171	goto err;
5c6bf031 BM	172	#endif
62dd6f16	173	}
5c6bf031	174	else if (BN_ucmp(BN_get0_nist_prime_384(), p) == 0)
62dd6f16	175	{
19b8d06a BM	176	#if !defined(NO_32_BIT_TYPE) \|\| defined(OPENSSL_NO_ASM)
19b8d06a BM	177	group->field_mod_func = BN_nist_mod_384;
5c6bf031	178	#else
19b8d06a	179	ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE_GFP, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
5c6bf031 BM	180	goto err;
5c6bf031 BM	181	#endif
62dd6f16	182	}
5c6bf031	183	else if (BN_ucmp(BN_get0_nist_prime_521(), p) == 0)
19b8d06a BM	184	/* this one works in the NO_32_BIT_TYPE case */
19b8d06a BM	185	group->field_mod_func = BN_nist_mod_521;
5c6bf031 BM	186	else
5c6bf031 BM	187	{
19b8d06a	188	ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE_GFP, EC_R_NOT_A_NIST_PRIME);
5c6bf031 BM	189	goto err;
	190	}
	191
	192	/* group->field */
	193	if (!BN_copy(&group->field, p)) goto err;
b53e44e5	194	BN_set_sign(&group->field, 0);
5c6bf031 BM	195
5c6bf031 BM	196	/* group->a */
19b8d06a	197	if (!group->field_mod_func(&group->a, a, p, ctx)) goto err;
5c6bf031 BM	198
5c6bf031 BM	199	/* group->b */
19b8d06a	200	if (!group->field_mod_func(&group->b, b, p, ctx)) goto err;
5c6bf031 BM	201
	202	/* group->a_is_minus3 */
	203	if (!BN_add_word(tmp_bn, 3)) goto err;
	204	group->a_is_minus3 = (0 == BN_cmp(tmp_bn, &group->field));
	205
	206	ret = 1;
	207
	208	err:
	209	BN_CTX_end(ctx);
	210	if (new_ctx != NULL)
	211	BN_CTX_free(new_ctx);
	212	return ret;
	213	}
	214
	215	int ec_GFp_nist_group_copy(EC_GROUP dest, const EC_GROUP src)
	216	{
	217	if (dest == NULL \|\| src == NULL)
	218	return 0;
	219
	220	if (!BN_copy(&dest->field, &src->field))
	221	return 0;
	222	if (!BN_copy(&dest->a, &src->a))
	223	return 0;
	224	if (!BN_copy(&dest->b, &src->b))
	225	return 0;
60428dbf	226
5c6bf031	227	dest->curve_name = src->curve_name;
60428dbf	228
5c6bf031	229	dest->a_is_minus3 = src->a_is_minus3;
60428dbf	230
5c6bf031 BM	231	dest->field_data1 = src->field_data1;
	232
	233	return 1;
	234	}
60428dbf	235
5c6bf031 BM	236	int ec_GFp_nist_field_mul(const EC_GROUP group, BIGNUM r, const BIGNUM *a,
	237	const BIGNUM b, BN_CTX ctx)
	238	{
	239	int ret=0;
	240	BN_CTX *ctx_new=NULL;
60428dbf	241
5c6bf031 BM	242	if (!group \|\| !r \|\| !a \|\| !b)
	243	{
	244	ECerr(EC_F_EC_GFP_NIST_FIELD_MUL, ERR_R_PASSED_NULL_PARAMETER);
	245	goto err;
	246	}
	247	if (!ctx)
	248	if ((ctx_new = ctx = BN_CTX_new()) == NULL) goto err;
60428dbf	249
5c6bf031	250	if (!BN_mul(r, a, b, ctx)) goto err;
19b8d06a	251	if (!group->field_mod_func(r, r, &group->field, ctx))
5c6bf031	252	goto err;
60428dbf	253
5c6bf031 BM	254	ret=1;
	255	err:
	256	if (ctx_new)
	257	BN_CTX_free(ctx_new);
	258	return ret;
	259	}
60428dbf	260
5c6bf031 BM	261	int ec_GFp_nist_field_sqr(const EC_GROUP group, BIGNUM r, const BIGNUM *a,
	262	BN_CTX *ctx)
	263	{
	264	int ret=0;
	265	BN_CTX *ctx_new=NULL;
60428dbf	266
5c6bf031 BM	267	if (!group \|\| !r \|\| !a)
	268	{
	269	ECerr(EC_F_EC_GFP_NIST_FIELD_SQR, EC_R_PASSED_NULL_PARAMETER);
	270	goto err;
	271	}
	272	if (!ctx)
	273	if ((ctx_new = ctx = BN_CTX_new()) == NULL) goto err;
60428dbf	274
5c6bf031	275	if (!BN_sqr(r, a, ctx)) goto err;
19b8d06a	276	if (!group->field_mod_func(r, r, &group->field, ctx))
5c6bf031	277	goto err;
60428dbf	278
5c6bf031 BM	279	ret=1;
	280	err:
	281	if (ctx_new)
	282	BN_CTX_free(ctx_new);
	283	return ret;
	284	}