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copy_conditional(x_out, x1, z2_is_zero);
copy_conditional(y_out, y2, z1_is_zero);
copy_conditional(y_out, y1, z2_is_zero);
copy_conditional(z_out, z2, z1_is_zero);
copy_conditional(z_out, z1, z2_is_zero);
felem_assign(x3, x_out);
felem_assign(y3, y_out);
felem_assign(z3, z_out);
}
/* select_point selects the |idx|th point from a precomputation table and
* copies it to out. */
static void select_point(const u64 idx, unsigned int size, const felem pre_comp[/*size*/][3], felem out[3])
{
unsigned i, j;
limb *outlimbs = &out[0][0];
memset(outlimbs, 0, 3 * sizeof(felem));
for (i = 0; i < size; i++)
{
const limb *inlimbs = &pre_comp[i][0][0];
u64 mask = i ^ idx;
mask |= mask >> 4;
mask |= mask >> 2;
mask |= mask >> 1;
mask &= 1;
mask--;
for (j = 0; j < 4 * 3; j++)
outlimbs[j] |= inlimbs[j] & mask;
}
}
/* get_bit returns the |i|th bit in |in| */
static char get_bit(const felem_bytearray in, unsigned i)
{
if (i >= 224)
return 0;
return (in[i >> 3] >> (i & 7)) & 1;
}
/* Interleaved point multiplication using precomputed point multiples:
* The small point multiples 0*P, 1*P, ..., 16*P are in pre_comp[],
* the scalars in scalars[]. If g_scalar is non-NULL, we also add this multiple
* of the generator, using certain (large) precomputed multiples in g_pre_comp.
* Output point (X, Y, Z) is stored in x_out, y_out, z_out */
static void batch_mul(felem x_out, felem y_out, felem z_out,
const felem_bytearray scalars[], const unsigned num_points, const u8 *g_scalar,
const int mixed, const felem pre_comp[][17][3], const felem g_pre_comp[2][16][3])
{
int i, skip;
unsigned num;
unsigned gen_mul = (g_scalar != NULL);
felem nq[3], tmp[4];
u64 bits;
u8 sign, digit;
/* set nq to the point at infinity */
memset(nq, 0, 3 * sizeof(felem));
/* Loop over all scalars msb-to-lsb, interleaving additions
* of multiples of the generator (two in each of the last 28 rounds)
* and additions of other points multiples (every 5th round).
*/
skip = 1; /* save two point operations in the first round */
for (i = (num_points ? 220 : 27); i >= 0; --i)
{
/* double */
if (!skip)
point_double(nq[0], nq[1], nq[2], nq[0], nq[1], nq[2]);
/* add multiples of the generator */
if (gen_mul && (i <= 27))
{
/* first, look 28 bits upwards */
bits = get_bit(g_scalar, i + 196) << 3;
bits |= get_bit(g_scalar, i + 140) << 2;
bits |= get_bit(g_scalar, i + 84) << 1;
bits |= get_bit(g_scalar, i + 28);
/* select the point to add, in constant time */
select_point(bits, 16, g_pre_comp[1], tmp);
if (!skip)
{
point_add(nq[0], nq[1], nq[2],
nq[0], nq[1], nq[2],
1 /* mixed */, tmp[0], tmp[1], tmp[2]);
}
else
{
memcpy(nq, tmp, 3 * sizeof(felem));
skip = 0;
}
/* second, look at the current position */
bits = get_bit(g_scalar, i + 168) << 3;
bits |= get_bit(g_scalar, i + 112) << 2;
bits |= get_bit(g_scalar, i + 56) << 1;
bits |= get_bit(g_scalar, i);
/* select the point to add, in constant time */
select_point(bits, 16, g_pre_comp[0], tmp);
point_add(nq[0], nq[1], nq[2],
nq[0], nq[1], nq[2],
1 /* mixed */, tmp[0], tmp[1], tmp[2]);
}
/* do other additions every 5 doublings */
if (num_points && (i % 5 == 0))
{
/* loop over all scalars */
for (num = 0; num < num_points; ++num)
{
bits = get_bit(scalars[num], i + 4) << 5;
bits |= get_bit(scalars[num], i + 3) << 4;
bits |= get_bit(scalars[num], i + 2) << 3;
bits |= get_bit(scalars[num], i + 1) << 2;
bits |= get_bit(scalars[num], i) << 1;
bits |= get_bit(scalars[num], i - 1);
ec_GFp_nistp_recode_scalar_bits(&sign, &digit, bits);
/* select the point to add or subtract */
select_point(digit, 17, pre_comp[num], tmp);
felem_neg(tmp[3], tmp[1]); /* (X, -Y, Z) is the negative point */
copy_conditional(tmp[1], tmp[3], sign);
if (!skip)
{
point_add(nq[0], nq[1], nq[2],
nq[0], nq[1], nq[2],
mixed, tmp[0], tmp[1], tmp[2]);
}
else
{
memcpy(nq, tmp, 3 * sizeof(felem));
skip = 0;
}
}
}
}
felem_assign(x_out, nq[0]);
felem_assign(y_out, nq[1]);
felem_assign(z_out, nq[2]);
}
/******************************************************************************/
/* FUNCTIONS TO MANAGE PRECOMPUTATION
*/
static NISTP224_PRE_COMP *nistp224_pre_comp_new()
{
NISTP224_PRE_COMP *ret = NULL;
ret = (NISTP224_PRE_COMP *) OPENSSL_malloc(sizeof *ret);
if (!ret)
{
ECerr(EC_F_NISTP224_PRE_COMP_NEW, ERR_R_MALLOC_FAILURE);
return ret;
}
memset(ret->g_pre_comp, 0, sizeof(ret->g_pre_comp));
ret->references = 1;
return ret;
}
static void *nistp224_pre_comp_dup(void *src_)
{
NISTP224_PRE_COMP *src = src_;
/* no need to actually copy, these objects never change! */
CRYPTO_add(&src->references, 1, CRYPTO_LOCK_EC_PRE_COMP);
return src_;
}
static void nistp224_pre_comp_free(void *pre_)
{
int i;
NISTP224_PRE_COMP *pre = pre_;
if (!pre)
return;
i = CRYPTO_add(&pre->references, -1, CRYPTO_LOCK_EC_PRE_COMP);
if (i > 0)
return;
OPENSSL_free(pre);
}
static void nistp224_pre_comp_clear_free(void *pre_)
{
int i;
NISTP224_PRE_COMP *pre = pre_;
if (!pre)
return;
i = CRYPTO_add(&pre->references, -1, CRYPTO_LOCK_EC_PRE_COMP);
if (i > 0)
return;
OPENSSL_cleanse(pre, sizeof *pre);
OPENSSL_free(pre);
}
/******************************************************************************/
/* OPENSSL EC_METHOD FUNCTIONS
*/
int ec_GFp_nistp224_group_init(EC_GROUP *group)
{
int ret;
ret = ec_GFp_simple_group_init(group);
group->a_is_minus3 = 1;
return ret;
}
int ec_GFp_nistp224_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 *curve_p, *curve_a, *curve_b;
if (ctx == NULL)
if ((ctx = new_ctx = BN_CTX_new()) == NULL) return 0;
BN_CTX_start(ctx);
if (((curve_p = BN_CTX_get(ctx)) == NULL) ||
((curve_a = BN_CTX_get(ctx)) == NULL) ||
((curve_b = BN_CTX_get(ctx)) == NULL)) goto err;
BN_bin2bn(nistp224_curve_params[0], sizeof(felem_bytearray), curve_p);
BN_bin2bn(nistp224_curve_params[1], sizeof(felem_bytearray), curve_a);
BN_bin2bn(nistp224_curve_params[2], sizeof(felem_bytearray), curve_b);
if ((BN_cmp(curve_p, p)) || (BN_cmp(curve_a, a)) ||
(BN_cmp(curve_b, b)))
{
ECerr(EC_F_EC_GFP_NISTP224_GROUP_SET_CURVE,
EC_R_WRONG_CURVE_PARAMETERS);
goto err;
}
group->field_mod_func = BN_nist_mod_224;
ret = ec_GFp_simple_group_set_curve(group, p, a, b, ctx);
err:
BN_CTX_end(ctx);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
return ret;
}
/* Takes the Jacobian coordinates (X, Y, Z) of a point and returns
* (X', Y') = (X/Z^2, Y/Z^3) */
int ec_GFp_nistp224_point_get_affine_coordinates(const EC_GROUP *group,
const EC_POINT *point, BIGNUM *x, BIGNUM *y, BN_CTX *ctx)
{
felem z1, z2, x_in, y_in, x_out, y_out;
widefelem tmp;
if (EC_POINT_is_at_infinity(group, point))
{
ECerr(EC_F_EC_GFP_NISTP224_POINT_GET_AFFINE_COORDINATES,
EC_R_POINT_AT_INFINITY);
return 0;
}
if ((!BN_to_felem(x_in, &point->X)) || (!BN_to_felem(y_in, &point->Y)) ||
(!BN_to_felem(z1, &point->Z))) return 0;
felem_inv(z2, z1);
felem_square(tmp, z2); felem_reduce(z1, tmp);
felem_mul(tmp, x_in, z1); felem_reduce(x_in, tmp);
felem_contract(x_out, x_in);
if (x != NULL)
{
if (!felem_to_BN(x, x_out)) {
ECerr(EC_F_EC_GFP_NISTP224_POINT_GET_AFFINE_COORDINATES,
ERR_R_BN_LIB);
return 0;
}
}
felem_mul(tmp, z1, z2); felem_reduce(z1, tmp);
felem_mul(tmp, y_in, z1); felem_reduce(y_in, tmp);
felem_contract(y_out, y_in);
if (y != NULL)
{
if (!felem_to_BN(y, y_out)) {
ECerr(EC_F_EC_GFP_NISTP224_POINT_GET_AFFINE_COORDINATES,
ERR_R_BN_LIB);
return 0;
}
}
return 1;
}
static void make_points_affine(size_t num, felem points[/*num*/][3], felem tmp_felems[/*num+1*/])
{
/* Runs in constant time, unless an input is the point at infinity
* (which normally shouldn't happen). */
ec_GFp_nistp_points_make_affine_internal(
num,
points,
sizeof(felem),
tmp_felems,
(void (*)(void *)) felem_one,
(int (*)(const void *)) felem_is_zero_int,
(void (*)(void *, const void *)) felem_assign,
(void (*)(void *, const void *)) felem_square_reduce,
(void (*)(void *, const void *, const void *)) felem_mul_reduce,
(void (*)(void *, const void *)) felem_inv,
(void (*)(void *, const void *)) felem_contract);
}
/* Computes scalar*generator + \sum scalars[i]*points[i], ignoring NULL values
* Result is stored in r (r can equal one of the inputs). */
int ec_GFp_nistp224_points_mul(const EC_GROUP *group, EC_POINT *r,
const BIGNUM *scalar, size_t num, const EC_POINT *points[],
const BIGNUM *scalars[], BN_CTX *ctx)
{
int ret = 0;
int j;
unsigned i;
int mixed = 0;
BN_CTX *new_ctx = NULL;
BIGNUM *x, *y, *z, *tmp_scalar;
felem_bytearray g_secret;
felem_bytearray *secrets = NULL;
felem (*pre_comp)[17][3] = NULL;
felem *tmp_felems = NULL;
felem_bytearray tmp;
unsigned num_bytes;
int have_pre_comp = 0;
size_t num_points = num;
felem x_in, y_in, z_in, x_out, y_out, z_out;
NISTP224_PRE_COMP *pre = NULL;
const felem (*g_pre_comp)[16][3] = NULL;
EC_POINT *generator = NULL;
const EC_POINT *p = NULL;
const BIGNUM *p_scalar = NULL;
if (ctx == NULL)
if ((ctx = new_ctx = BN_CTX_new()) == NULL) return 0;
BN_CTX_start(ctx);
if (((x = BN_CTX_get(ctx)) == NULL) ||
((y = BN_CTX_get(ctx)) == NULL) ||
((z = BN_CTX_get(ctx)) == NULL) ||
((tmp_scalar = BN_CTX_get(ctx)) == NULL))
goto err;
if (scalar != NULL)
{
pre = EC_EX_DATA_get_data(group->extra_data,
nistp224_pre_comp_dup, nistp224_pre_comp_free,
nistp224_pre_comp_clear_free);
if (pre)
/* we have precomputation, try to use it */
g_pre_comp = (const felem (*)[16][3]) pre->g_pre_comp;
else
/* try to use the standard precomputation */
g_pre_comp = &gmul[0];
generator = EC_POINT_new(group);
if (generator == NULL)
goto err;
/* get the generator from precomputation */
if (!felem_to_BN(x, g_pre_comp[0][1][0]) ||
!felem_to_BN(y, g_pre_comp[0][1][1]) ||
!felem_to_BN(z, g_pre_comp[0][1][2]))
{
ECerr(EC_F_EC_GFP_NISTP224_POINTS_MUL, ERR_R_BN_LIB);
goto err;
}
if (!EC_POINT_set_Jprojective_coordinates_GFp(group,
generator, x, y, z, ctx))
goto err;
if (0 == EC_POINT_cmp(group, generator, group->generator, ctx))
/* precomputation matches generator */
have_pre_comp = 1;
else
/* we don't have valid precomputation:
* treat the generator as a random point */
num_points = num_points + 1;
}
if (num_points > 0)
{
if (num_points >= 3)
{
/* unless we precompute multiples for just one or two points,
* converting those into affine form is time well spent */
mixed = 1;
}
secrets = OPENSSL_malloc(num_points * sizeof(felem_bytearray));
pre_comp = OPENSSL_malloc(num_points * 17 * 3 * sizeof(felem));
if (mixed)
tmp_felems = OPENSSL_malloc((num_points * 17 + 1) * sizeof(felem));
if ((secrets == NULL) || (pre_comp == NULL) || (mixed && (tmp_felems == NULL)))
{
ECerr(EC_F_EC_GFP_NISTP224_POINTS_MUL, ERR_R_MALLOC_FAILURE);
goto err;
}
/* we treat NULL scalars as 0, and NULL points as points at infinity,
* i.e., they contribute nothing to the linear combination */
memset(secrets, 0, num_points * sizeof(felem_bytearray));
memset(pre_comp, 0, num_points * 17 * 3 * sizeof(felem));
for (i = 0; i < num_points; ++i)
{
if (i == num)
/* the generator */
{
p = EC_GROUP_get0_generator(group);
p_scalar = scalar;
}
else
/* the i^th point */
{
p = points[i];
p_scalar = scalars[i];
}
if ((p_scalar != NULL) && (p != NULL))
{
/* reduce scalar to 0 <= scalar < 2^224 */
if ((BN_num_bits(p_scalar) > 224) || (BN_is_negative(p_scalar)))
{
/* this is an unusual input, and we don't guarantee
* constant-timeness */
if (!BN_nnmod(tmp_scalar, p_scalar, &group->order, ctx))
{
ECerr(EC_F_EC_GFP_NISTP224_POINTS_MUL, ERR_R_BN_LIB);
goto err;
}
num_bytes = BN_bn2bin(tmp_scalar, tmp);
}
else
num_bytes = BN_bn2bin(p_scalar, tmp);
flip_endian(secrets[i], tmp, num_bytes);
/* precompute multiples */
if ((!BN_to_felem(x_out, &p->X)) ||
(!BN_to_felem(y_out, &p->Y)) ||
(!BN_to_felem(z_out, &p->Z))) goto err;
felem_assign(pre_comp[i][1][0], x_out);
felem_assign(pre_comp[i][1][1], y_out);
felem_assign(pre_comp[i][1][2], z_out);
for (j = 2; j <= 16; ++j)
{
if (j & 1)
{
point_add(
pre_comp[i][j][0], pre_comp[i][j][1], pre_comp[i][j][2],
pre_comp[i][1][0], pre_comp[i][1][1], pre_comp[i][1][2],
0, pre_comp[i][j-1][0], pre_comp[i][j-1][1], pre_comp[i][j-1][2]);
}
else
{
point_double(
pre_comp[i][j][0], pre_comp[i][j][1], pre_comp[i][j][2],
pre_comp[i][j/2][0], pre_comp[i][j/2][1], pre_comp[i][j/2][2]);
}
}
}
}
if (mixed)
make_points_affine(num_points * 17, pre_comp[0], tmp_felems);
}
/* the scalar for the generator */
if ((scalar != NULL) && (have_pre_comp))
{
memset(g_secret, 0, sizeof g_secret);
/* reduce scalar to 0 <= scalar < 2^224 */
if ((BN_num_bits(scalar) > 224) || (BN_is_negative(scalar)))
{
/* this is an unusual input, and we don't guarantee
* constant-timeness */
if (!BN_nnmod(tmp_scalar, scalar, &group->order, ctx))
{
ECerr(EC_F_EC_GFP_NISTP224_POINTS_MUL, ERR_R_BN_LIB);
goto err;
}
num_bytes = BN_bn2bin(tmp_scalar, tmp);
}
else
num_bytes = BN_bn2bin(scalar, tmp);
flip_endian(g_secret, tmp, num_bytes);
/* do the multiplication with generator precomputation*/
batch_mul(x_out, y_out, z_out,
(const felem_bytearray (*)) secrets, num_points,
g_secret,
mixed, (const felem (*)[17][3]) pre_comp,
g_pre_comp);
}
else
/* do the multiplication without generator precomputation */
batch_mul(x_out, y_out, z_out,
(const felem_bytearray (*)) secrets, num_points,
NULL, mixed, (const felem (*)[17][3]) pre_comp, NULL);
/* reduce the output to its unique minimal representation */
felem_contract(x_in, x_out);
felem_contract(y_in, y_out);
felem_contract(z_in, z_out);
if ((!felem_to_BN(x, x_in)) || (!felem_to_BN(y, y_in)) ||
(!felem_to_BN(z, z_in)))
{
ECerr(EC_F_EC_GFP_NISTP224_POINTS_MUL, ERR_R_BN_LIB);
goto err;
}
ret = EC_POINT_set_Jprojective_coordinates_GFp(group, r, x, y, z, ctx);
err:
BN_CTX_end(ctx);
if (generator != NULL)
EC_POINT_free(generator);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
if (secrets != NULL)
OPENSSL_free(secrets);
if (pre_comp != NULL)
OPENSSL_free(pre_comp);
if (tmp_felems != NULL)
OPENSSL_free(tmp_felems);
return ret;
}
int ec_GFp_nistp224_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
{
int ret = 0;
NISTP224_PRE_COMP *pre = NULL;
int i, j;
BN_CTX *new_ctx = NULL;
BIGNUM *x, *y;
EC_POINT *generator = NULL;
felem tmp_felems[32];
/* throw away old precomputation */
EC_EX_DATA_free_data(&group->extra_data, nistp224_pre_comp_dup,
nistp224_pre_comp_free, nistp224_pre_comp_clear_free);
if (ctx == NULL)
if ((ctx = new_ctx = BN_CTX_new()) == NULL) return 0;
BN_CTX_start(ctx);
if (((x = BN_CTX_get(ctx)) == NULL) ||
((y = BN_CTX_get(ctx)) == NULL))
goto err;
/* get the generator */
if (group->generator == NULL) goto err;
generator = EC_POINT_new(group);
if (generator == NULL)
goto err;
BN_bin2bn(nistp224_curve_params[3], sizeof (felem_bytearray), x);
BN_bin2bn(nistp224_curve_params[4], sizeof (felem_bytearray), y);
if (!EC_POINT_set_affine_coordinates_GFp(group, generator, x, y, ctx))
goto err;
if ((pre = nistp224_pre_comp_new()) == NULL)
goto err;
/* if the generator is the standard one, use built-in precomputation */
if (0 == EC_POINT_cmp(group, generator, group->generator, ctx))
{
memcpy(pre->g_pre_comp, gmul, sizeof(pre->g_pre_comp));
ret = 1;
goto err;
}
if ((!BN_to_felem(pre->g_pre_comp[0][1][0], &group->generator->X)) ||
(!BN_to_felem(pre->g_pre_comp[0][1][1], &group->generator->Y)) ||
(!BN_to_felem(pre->g_pre_comp[0][1][2], &group->generator->Z)))
goto err;
/* compute 2^56*G, 2^112*G, 2^168*G for the first table,
* 2^28*G, 2^84*G, 2^140*G, 2^196*G for the second one
*/
for (i = 1; i <= 8; i <<= 1)
{
point_double(
pre->g_pre_comp[1][i][0], pre->g_pre_comp[1][i][1], pre->g_pre_comp[1][i][2],
pre->g_pre_comp[0][i][0], pre->g_pre_comp[0][i][1], pre->g_pre_comp[0][i][2]);
for (j = 0; j < 27; ++j)
{
point_double(
pre->g_pre_comp[1][i][0], pre->g_pre_comp[1][i][1], pre->g_pre_comp[1][i][2],
pre->g_pre_comp[1][i][0], pre->g_pre_comp[1][i][1], pre->g_pre_comp[1][i][2]);
}
if (i == 8)
break;
point_double(
pre->g_pre_comp[0][2*i][0], pre->g_pre_comp[0][2*i][1], pre->g_pre_comp[0][2*i][2],
pre->g_pre_comp[1][i][0], pre->g_pre_comp[1][i][1], pre->g_pre_comp[1][i][2]);
for (j = 0; j < 27; ++j)
{
point_double(
pre->g_pre_comp[0][2*i][0], pre->g_pre_comp[0][2*i][1], pre->g_pre_comp[0][2*i][2],
pre->g_pre_comp[0][2*i][0], pre->g_pre_comp[0][2*i][1], pre->g_pre_comp[0][2*i][2]);
}
}
for (i = 0; i < 2; i++)
{
/* g_pre_comp[i][0] is the point at infinity */
memset(pre->g_pre_comp[i][0], 0, sizeof(pre->g_pre_comp[i][0]));
/* the remaining multiples */
/* 2^56*G + 2^112*G resp. 2^84*G + 2^140*G */
point_add(
pre->g_pre_comp[i][6][0], pre->g_pre_comp[i][6][1],
pre->g_pre_comp[i][6][2], pre->g_pre_comp[i][4][0],
pre->g_pre_comp[i][4][1], pre->g_pre_comp[i][4][2],
0, pre->g_pre_comp[i][2][0], pre->g_pre_comp[i][2][1],
pre->g_pre_comp[i][2][2]);
/* 2^56*G + 2^168*G resp. 2^84*G + 2^196*G */
point_add(
pre->g_pre_comp[i][10][0], pre->g_pre_comp[i][10][1],
pre->g_pre_comp[i][10][2], pre->g_pre_comp[i][8][0],
pre->g_pre_comp[i][8][1], pre->g_pre_comp[i][8][2],
0, pre->g_pre_comp[i][2][0], pre->g_pre_comp[i][2][1],
pre->g_pre_comp[i][2][2]);
/* 2^112*G + 2^168*G resp. 2^140*G + 2^196*G */
point_add(
pre->g_pre_comp[i][12][0], pre->g_pre_comp[i][12][1],
pre->g_pre_comp[i][12][2], pre->g_pre_comp[i][8][0],
pre->g_pre_comp[i][8][1], pre->g_pre_comp[i][8][2],
0, pre->g_pre_comp[i][4][0], pre->g_pre_comp[i][4][1],
pre->g_pre_comp[i][4][2]);
/* 2^56*G + 2^112*G + 2^168*G resp. 2^84*G + 2^140*G + 2^196*G */
point_add(
pre->g_pre_comp[i][14][0], pre->g_pre_comp[i][14][1],
pre->g_pre_comp[i][14][2], pre->g_pre_comp[i][12][0],
pre->g_pre_comp[i][12][1], pre->g_pre_comp[i][12][2],
0, pre->g_pre_comp[i][2][0], pre->g_pre_comp[i][2][1],
pre->g_pre_comp[i][2][2]);
for (j = 1; j < 8; ++j)
{
/* odd multiples: add G resp. 2^28*G */
point_add(
pre->g_pre_comp[i][2*j+1][0], pre->g_pre_comp[i][2*j+1][1],
pre->g_pre_comp[i][2*j+1][2], pre->g_pre_comp[i][2*j][0],
pre->g_pre_comp[i][2*j][1], pre->g_pre_comp[i][2*j][2],
0, pre->g_pre_comp[i][1][0], pre->g_pre_comp[i][1][1],
pre->g_pre_comp[i][1][2]);
}
}
make_points_affine(31, &(pre->g_pre_comp[0][1]), tmp_felems);
if (!EC_EX_DATA_set_data(&group->extra_data, pre, nistp224_pre_comp_dup,
nistp224_pre_comp_free, nistp224_pre_comp_clear_free))
goto err;
ret = 1;
pre = NULL;
err:
BN_CTX_end(ctx);
if (generator != NULL)
EC_POINT_free(generator);
if (new_ctx != NULL)
BN_CTX_free(new_ctx);
if (pre)
nistp224_pre_comp_free(pre);
return ret;
}
int ec_GFp_nistp224_have_precompute_mult(const EC_GROUP *group)
{
if (EC_EX_DATA_get_data(group->extra_data, nistp224_pre_comp_dup,
nistp224_pre_comp_free, nistp224_pre_comp_clear_free)
!= NULL)
return 1;
else
return 0;
}
#else
static void *dummy=&dummy;
#endif