openssl/ec_curve.c

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/* crypto/ec/ec_curve.c */
/*
* Written by Nils Larsch for the OpenSSL project.
*/
/* ====================================================================
* Copyright (c) 1998-2010 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 the attached software ("Contribution") are developed by
* SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
*
* The Contribution is licensed pursuant to the OpenSSL open source
* license provided above.
*
* The elliptic curve binary polynomial software is originally written by
* Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems Laboratories.
*
*/
#include "ec_lcl.h"
#include <openssl/err.h>
#include <openssl/obj_mac.h>
#include <openssl/opensslconf.h>
typedef struct {
int field_type, /* either NID_X9_62_prime_field or
* NID_X9_62_characteristic_two_field */
seed_len,
param_len;
unsigned int cofactor; /* promoted to BN_ULONG */
} EC_CURVE_DATA;
static const struct { EC_CURVE_DATA h; unsigned char data[20+48*6]; }
_EC_NIST_PRIME_384 = {
{ NID_X9_62_prime_field,20,48,1 },
{ 0xA3,0x35,0x92,0x6A,0xA3,0x19,0xA2,0x7A,0x1D,0x00, /* seed */
0x89,0x6A,0x67,0x73,0xA4,0x82,0x7A,0xCD,0xAC,0x73,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, /* p */
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFE,0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, /* a */
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFE,0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0xFF,0xFF,0xFF,0xFC,
0xB3,0x31,0x2F,0xA7,0xE2,0x3E,0xE7,0xE4,0x98,0x8E, /* b */
0x05,0x6B,0xE3,0xF8,0x2D,0x19,0x18,0x1D,0x9C,0x6E,
0xFE,0x81,0x41,0x12,0x03,0x14,0x08,0x8F,0x50,0x13,
0x87,0x5A,0xC6,0x56,0x39,0x8D,0x8A,0x2E,0xD1,0x9D,
0x2A,0x85,0xC8,0xED,0xD3,0xEC,0x2A,0xEF,
0xAA,0x87,0xCA,0x22,0xBE,0x8B,0x05,0x37,0x8E,0xB1, /* x */
0xC7,0x1E,0xF3,0x20,0xAD,0x74,0x6E,0x1D,0x3B,0x62,
0x8B,0xA7,0x9B,0x98,0x59,0xF7,0x41,0xE0,0x82,0x54,
0x2A,0x38,0x55,0x02,0xF2,0x5D,0xBF,0x55,0x29,0x6C,
0x3A,0x54,0x5E,0x38,0x72,0x76,0x0A,0xB7,
0x36,0x17,0xde,0x4a,0x96,0x26,0x2c,0x6f,0x5d,0x9e, /* y */
0x98,0xbf,0x92,0x92,0xdc,0x29,0xf8,0xf4,0x1d,0xbd,
0x28,0x9a,0x14,0x7c,0xe9,0xda,0x31,0x13,0xb5,0xf0,
0xb8,0xc0,0x0a,0x60,0xb1,0xce,0x1d,0x7e,0x81,0x9d,
0x7a,0x43,0x1d,0x7c,0x90,0xea,0x0e,0x5f,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF, /* order */
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xC7,0x63,0x4D,0x81,0xF4,0x37,
0x2D,0xDF,0x58,0x1A,0x0D,0xB2,0x48,0xB0,0xA7,0x7A,
0xEC,0xEC,0x19,0x6A,0xCC,0xC5,0x29,0x73 }
};
static const struct { EC_CURVE_DATA h; unsigned char data[20+32*6]; }
_EC_X9_62_PRIME_256V1 = {
{ NID_X9_62_prime_field,20,32,1 },
{ 0xC4,0x9D,0x36,0x08,0x86,0xE7,0x04,0x93,0x6A,0x66, /* seed */
0x78,0xE1,0x13,0x9D,0x26,0xB7,0x81,0x9F,0x7E,0x90,
0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x01,0x00,0x00, /* p */
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x01,0x00,0x00, /* a */
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFC,
0x5A,0xC6,0x35,0xD8,0xAA,0x3A,0x93,0xE7,0xB3,0xEB, /* b */
0xBD,0x55,0x76,0x98,0x86,0xBC,0x65,0x1D,0x06,0xB0,
0xCC,0x53,0xB0,0xF6,0x3B,0xCE,0x3C,0x3E,0x27,0xD2,
0x60,0x4B,
0x6B,0x17,0xD1,0xF2,0xE1,0x2C,0x42,0x47,0xF8,0xBC, /* x */
0xE6,0xE5,0x63,0xA4,0x40,0xF2,0x77,0x03,0x7D,0x81,
0x2D,0xEB,0x33,0xA0,0xF4,0xA1,0x39,0x45,0xD8,0x98,
0xC2,0x96,
0x4f,0xe3,0x42,0xe2,0xfe,0x1a,0x7f,0x9b,0x8e,0xe7, /* y */
0xeb,0x4a,0x7c,0x0f,0x9e,0x16,0x2b,0xce,0x33,0x57,
0x6b,0x31,0x5e,0xce,0xcb,0xb6,0x40,0x68,0x37,0xbf,
0x51,0xf5,
0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0xFF,0xFF, /* order */
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xBC,0xE6,0xFA,0xAD,
0xA7,0x17,0x9E,0x84,0xF3,0xB9,0xCA,0xC2,0xFC,0x63,
0x25,0x51 }
};
typedef struct _ec_list_element_st {
int nid;
const EC_CURVE_DATA *data;
const EC_METHOD *(*meth)(void);
const char *comment;
} ec_list_element;
static const ec_list_element curve_list[] = {
/* prime field curves */
/* secg curves */
/* SECG secp256r1 is the same as X9.62 prime256v1 and hence omitted */
{ NID_secp384r1, &_EC_NIST_PRIME_384.h, 0, "NIST/SECG curve over a 384 bit prime field" },
#ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
{ NID_X9_62_prime256v1, &_EC_X9_62_PRIME_256V1.h, EC_GFp_nistp256_method, "X9.62/SECG curve over a 256 bit prime field" },
#else
{ NID_X9_62_prime256v1, &_EC_X9_62_PRIME_256V1.h, 0, "X9.62/SECG curve over a 256 bit prime field" },
#endif
};
#define curve_list_length (sizeof(curve_list)/sizeof(ec_list_element))
static EC_GROUP *ec_group_new_from_data(const ec_list_element curve)
{
EC_GROUP *group=NULL;
EC_POINT *P=NULL;
BN_CTX *ctx=NULL;
BIGNUM *p=NULL, *a=NULL, *b=NULL, *x=NULL, *y=NULL, *order=NULL;
int ok=0;
int seed_len,param_len;
const EC_METHOD *meth;
const EC_CURVE_DATA *data;
const unsigned char *params;
if ((ctx = BN_CTX_new()) == NULL)
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_MALLOC_FAILURE);
goto err;
}
data = curve.data;
seed_len = data->seed_len;
param_len = data->param_len;
params = (const unsigned char *)(data+1); /* skip header */
params += seed_len; /* skip seed */
if (!(p = BN_bin2bn(params+0*param_len, param_len, NULL))
|| !(a = BN_bin2bn(params+1*param_len, param_len, NULL))
|| !(b = BN_bin2bn(params+2*param_len, param_len, NULL)))
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_BN_LIB);
goto err;
}
if (curve.meth != 0)
{
meth = curve.meth();
if (((group = EC_GROUP_new(meth)) == NULL) ||
(!(group->meth->group_set_curve(group, p, a, b, ctx))))
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
}
else if (data->field_type == NID_X9_62_prime_field)
{
if ((group = EC_GROUP_new_curve_GFp(p, a, b, ctx)) == NULL)
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
}
#ifndef OPENSSL_NO_EC2M
else /* field_type == NID_X9_62_characteristic_two_field */
{
if ((group = EC_GROUP_new_curve_GF2m(p, a, b, ctx)) == NULL)
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
}
#endif
if ((P = EC_POINT_new(group)) == NULL)
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
if (!(x = BN_bin2bn(params+3*param_len, param_len, NULL))
|| !(y = BN_bin2bn(params+4*param_len, param_len, NULL)))
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_BN_LIB);
goto err;
}
if (!EC_POINT_set_affine_coordinates_GFp(group, P, x, y, ctx))
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
if (!(order = BN_bin2bn(params+5*param_len, param_len, NULL))
|| !BN_set_word(x, (BN_ULONG)data->cofactor))
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_BN_LIB);
goto err;
}
if (!EC_GROUP_set_generator(group, P, order, x))
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
if (seed_len)
{
if (!EC_GROUP_set_seed(group, params-seed_len, seed_len))
{
ECerr(EC_F_EC_GROUP_NEW_FROM_DATA, ERR_R_EC_LIB);
goto err;
}
}
ok=1;
err:
if (!ok)
{
EC_GROUP_free(group);
group = NULL;
}
if (P)
EC_POINT_free(P);
if (ctx)
BN_CTX_free(ctx);
if (p)
BN_free(p);
if (a)
BN_free(a);
if (b)
BN_free(b);
if (order)
BN_free(order);
if (x)
BN_free(x);
if (y)
BN_free(y);
return group;
}
EC_GROUP *EC_GROUP_new_by_curve_name(int nid)
{
size_t i;
EC_GROUP *ret = NULL;
if (nid <= 0)
return NULL;
for (i=0; i<curve_list_length; i++)
if (curve_list[i].nid == nid)
{
ret = ec_group_new_from_data(curve_list[i]);
break;
}
if (ret == NULL)
{
ECerr(EC_F_EC_GROUP_NEW_BY_CURVE_NAME, EC_R_UNKNOWN_GROUP);
return NULL;
}
EC_GROUP_set_curve_name(ret, nid);
return ret;
}
size_t EC_get_builtin_curves(EC_builtin_curve *r, size_t nitems)
{
size_t i, min;
if (r == NULL || nitems == 0)
return curve_list_length;
min = nitems < curve_list_length ? nitems : curve_list_length;
for (i = 0; i < min; i++)
{
r[i].nid = curve_list[i].nid;
r[i].comment = curve_list[i].comment;
}
return curve_list_length;
}