X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fec%2Fecp_nistp256.c;h=4d284fa326cf639aebe48cce9fa14d99e5b23ae0;hp=6fce22eb61613e5c6944676371ab3af2fd82b8d5;hb=4fe2ee3a449a8ca2886584e221f34ff0ef5de119;hpb=4b45c6e52b208deff7da333d1c7f84bcd3986609 diff --git a/crypto/ec/ecp_nistp256.c b/crypto/ec/ecp_nistp256.c index 6fce22eb61..4d284fa326 100644 --- a/crypto/ec/ecp_nistp256.c +++ b/crypto/ec/ecp_nistp256.c @@ -1,7 +1,12 @@ -/* crypto/ec/ecp_nistp256.c */ /* - * Written by Adam Langley (Google) for the OpenSSL project + * Copyright 2011-2018 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the Apache License 2.0 (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html */ + /* Copyright 2011 Google Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); @@ -27,26 +32,27 @@ */ #include -#ifndef OPENSSL_NO_EC_NISTP_64_GCC_128 +#ifdef OPENSSL_NO_EC_NISTP_64_GCC_128 +NON_EMPTY_TRANSLATION_UNIT +#else # include # include # include # include "ec_lcl.h" -# if defined(__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)) +# if defined(__SIZEOF_INT128__) && __SIZEOF_INT128__==16 /* even with gcc, the typedef won't work for 32-bit platforms */ typedef __uint128_t uint128_t; /* nonstandard; implemented by gcc on 64-bit * platforms */ typedef __int128_t int128_t; # else -# error "Need GCC 3.1 or later to define type uint128_t" +# error "Your compiler doesn't appear to support 128-bit integer types" # endif typedef uint8_t u8; typedef uint32_t u32; typedef uint64_t u64; -typedef int64_t s64; /* * The underlying field. P256 operates over GF(2^256-2^224+2^192+2^96-1). We @@ -140,34 +146,21 @@ static void smallfelem_to_bin32(u8 out[32], const smallfelem in) *((u64 *)&out[24]) = in[3]; } -/* To preserve endianness when using BN_bn2bin and BN_bin2bn */ -static void flip_endian(u8 *out, const u8 *in, unsigned len) -{ - unsigned i; - for (i = 0; i < len; ++i) - out[i] = in[len - 1 - i]; -} - /* BN_to_felem converts an OpenSSL BIGNUM into an felem */ static int BN_to_felem(felem out, const BIGNUM *bn) { - felem_bytearray b_in; felem_bytearray b_out; - unsigned num_bytes; + int num_bytes; - /* BN_bn2bin eats leading zeroes */ - memset(b_out, 0, sizeof b_out); - num_bytes = BN_num_bytes(bn); - if (num_bytes > sizeof b_out) { + if (BN_is_negative(bn)) { ECerr(EC_F_BN_TO_FELEM, EC_R_BIGNUM_OUT_OF_RANGE); return 0; } - if (BN_is_negative(bn)) { + num_bytes = BN_bn2lebinpad(bn, b_out, sizeof(b_out)); + if (num_bytes < 0) { ECerr(EC_F_BN_TO_FELEM, EC_R_BIGNUM_OUT_OF_RANGE); return 0; } - num_bytes = BN_bn2bin(bn, b_in); - flip_endian(b_out, b_in, num_bytes); bin32_to_felem(out, b_out); return 1; } @@ -175,10 +168,9 @@ static int BN_to_felem(felem out, const BIGNUM *bn) /* felem_to_BN converts an felem into an OpenSSL BIGNUM */ static BIGNUM *smallfelem_to_BN(BIGNUM *out, const smallfelem in) { - felem_bytearray b_in, b_out; - smallfelem_to_bin32(b_in, in); - flip_endian(b_out, b_in, sizeof b_out); - return BN_bin2bn(b_out, sizeof b_out, out); + felem_bytearray b_out; + smallfelem_to_bin32(b_out, in); + return BN_lebin2bn(b_out, sizeof(b_out), out); } /*- @@ -387,7 +379,7 @@ static void felem_shrink(smallfelem out, const felem in) { felem tmp; u64 a, b, mask; - s64 high, low; + u64 high, low; static const u64 kPrime3Test = 0x7fffffff00000001ul; /* 2^63 - 2^32 + 1 */ /* Carry 2->3 */ @@ -428,29 +420,31 @@ static void felem_shrink(smallfelem out, const felem in) * In order to make space in tmp[3] for the carry from 2 -> 3, we * conditionally subtract kPrime if tmp[3] is large enough. */ - high = tmp[3] >> 64; + high = (u64)(tmp[3] >> 64); /* As tmp[3] < 2^65, high is either 1 or 0 */ - high <<= 63; - high >>= 63; + high = 0 - high; /*- * high is: * all ones if the high word of tmp[3] is 1 - * all zeros if the high word of tmp[3] if 0 */ - low = tmp[3]; - mask = low >> 63; + * all zeros if the high word of tmp[3] if 0 + */ + low = (u64)tmp[3]; + mask = 0 - (low >> 63); /*- * mask is: * all ones if the MSB of low is 1 - * all zeros if the MSB of low if 0 */ + * all zeros if the MSB of low if 0 + */ low &= bottom63bits; low -= kPrime3Test; /* if low was greater than kPrime3Test then the MSB is zero */ low = ~low; - low >>= 63; + low = 0 - (low >> 63); /*- * low is: * all ones if low was > kPrime3Test - * all zeros if low was <= kPrime3Test */ + * all zeros if low was <= kPrime3Test + */ mask = (mask & low) | high; tmp[0] -= mask & kPrime[0]; tmp[1] -= mask & kPrime[1]; @@ -884,7 +878,7 @@ static void felem_contract(smallfelem out, const felem in) equal &= equal << 4; equal &= equal << 2; equal &= equal << 1; - equal = ((s64) equal) >> 63; + equal = 0 - (equal >> 63); all_equal_so_far &= equal; } @@ -951,7 +945,7 @@ static limb smallfelem_is_zero(const smallfelem small) is_zero &= is_zero << 4; is_zero &= is_zero << 2; is_zero &= is_zero << 1; - is_zero = ((s64) is_zero) >> 63; + is_zero = 0 - (is_zero >> 63); is_p = (small[0] ^ kPrime[0]) | (small[1] ^ kPrime[1]) | @@ -963,7 +957,7 @@ static limb smallfelem_is_zero(const smallfelem small) is_p &= is_p << 4; is_p &= is_p << 2; is_p &= is_p << 1; - is_p = ((s64) is_p) >> 63; + is_p = 0 - (is_p >> 63); is_zero |= is_p; @@ -972,7 +966,7 @@ static limb smallfelem_is_zero(const smallfelem small) return result; } -static int smallfelem_is_zero_int(const smallfelem small) +static int smallfelem_is_zero_int(const void *small) { return (int)(smallfelem_is_zero(small) & ((limb) 1)); } @@ -1227,7 +1221,7 @@ static void copy_small_conditional(felem out, const smallfelem in, limb mask) } /*- - * point_add calcuates (x1, y1, z1) + (x2, y2, z2) + * point_add calculates (x1, y1, z1) + (x2, y2, z2) * * The method is taken from: * http://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-add-2007-bl, @@ -1624,7 +1618,8 @@ static void select_point(const u64 idx, unsigned int size, { unsigned i, j; u64 *outlimbs = &out[0][0]; - memset(outlimbs, 0, 3 * sizeof(smallfelem)); + + memset(out, 0, sizeof(*out) * 3); for (i = 0; i < size; i++) { const u64 *inlimbs = (u64 *)&pre_comp[i][0][0]; @@ -1668,7 +1663,7 @@ static void batch_mul(felem x_out, felem y_out, felem z_out, u8 sign, digit; /* set nq to the point at infinity */ - memset(nq, 0, 3 * sizeof(felem)); + memset(nq, 0, sizeof(nq)); /* * Loop over all scalars msb-to-lsb, interleaving additions of multiples @@ -1755,10 +1750,11 @@ static void batch_mul(felem x_out, felem y_out, felem z_out, } /* Precomputation for the group generator. */ -typedef struct { +struct nistp256_pre_comp_st { smallfelem g_pre_comp[2][16][3]; - int references; -} NISTP256_PRE_COMP; + CRYPTO_REF_COUNT references; + CRYPTO_RWLOCK *lock; +}; const EC_METHOD *EC_GFp_nistp256_method(void) { @@ -1772,6 +1768,7 @@ const EC_METHOD *EC_GFp_nistp256_method(void) ec_GFp_nistp256_group_set_curve, ec_GFp_simple_group_get_curve, ec_GFp_simple_group_get_degree, + ec_group_simple_order_bits, ec_GFp_simple_group_check_discriminant, ec_GFp_simple_point_init, ec_GFp_simple_point_finish, @@ -1799,9 +1796,27 @@ const EC_METHOD *EC_GFp_nistp256_method(void) ec_GFp_nist_field_mul, ec_GFp_nist_field_sqr, 0 /* field_div */ , + ec_GFp_simple_field_inv, 0 /* field_encode */ , 0 /* field_decode */ , - 0 /* field_set_to_one */ + 0, /* field_set_to_one */ + ec_key_simple_priv2oct, + ec_key_simple_oct2priv, + 0, /* set private */ + ec_key_simple_generate_key, + ec_key_simple_check_key, + ec_key_simple_generate_public_key, + 0, /* keycopy */ + 0, /* keyfinish */ + ecdh_simple_compute_key, + ecdsa_simple_sign_setup, + ecdsa_simple_sign_sig, + ecdsa_simple_verify_sig, + 0, /* field_inverse_mod_ord */ + 0, /* blind_coordinates */ + 0, /* ladder_pre */ + 0, /* ladder_step */ + 0 /* ladder_post */ }; return &ret; @@ -1812,57 +1827,49 @@ const EC_METHOD *EC_GFp_nistp256_method(void) * FUNCTIONS TO MANAGE PRECOMPUTATION */ -static NISTP256_PRE_COMP *nistp256_pre_comp_new() +static NISTP256_PRE_COMP *nistp256_pre_comp_new(void) { - NISTP256_PRE_COMP *ret = NULL; - ret = OPENSSL_malloc(sizeof *ret); - if (!ret) { + NISTP256_PRE_COMP *ret = OPENSSL_zalloc(sizeof(*ret)); + + if (ret == NULL) { ECerr(EC_F_NISTP256_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 *nistp256_pre_comp_dup(void *src_) -{ - NISTP256_PRE_COMP *src = src_; - - /* no need to actually copy, these objects never change! */ - CRYPTO_add(&src->references, 1, CRYPTO_LOCK_EC_PRE_COMP); + ret->references = 1; - return src_; + ret->lock = CRYPTO_THREAD_lock_new(); + if (ret->lock == NULL) { + ECerr(EC_F_NISTP256_PRE_COMP_NEW, ERR_R_MALLOC_FAILURE); + OPENSSL_free(ret); + return NULL; + } + return ret; } -static void nistp256_pre_comp_free(void *pre_) +NISTP256_PRE_COMP *EC_nistp256_pre_comp_dup(NISTP256_PRE_COMP *p) { int i; - NISTP256_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); + if (p != NULL) + CRYPTO_UP_REF(&p->references, &i, p->lock); + return p; } -static void nistp256_pre_comp_clear_free(void *pre_) +void EC_nistp256_pre_comp_free(NISTP256_PRE_COMP *pre) { int i; - NISTP256_PRE_COMP *pre = pre_; - if (!pre) + if (pre == NULL) return; - i = CRYPTO_add(&pre->references, -1, CRYPTO_LOCK_EC_PRE_COMP); + CRYPTO_DOWN_REF(&pre->references, &i, pre->lock); + REF_PRINT_COUNT("EC_nistp256", x); if (i > 0) return; + REF_ASSERT_ISNT(i < 0); - OPENSSL_clear_free(pre, sizeof *pre); + CRYPTO_THREAD_lock_free(pre->lock); + OPENSSL_free(pre); } /******************************************************************************/ @@ -1883,16 +1890,21 @@ int ec_GFp_nistp256_group_set_curve(EC_GROUP *group, const BIGNUM *p, BN_CTX *ctx) { int ret = 0; - BN_CTX *new_ctx = NULL; BIGNUM *curve_p, *curve_a, *curve_b; +#ifndef FIPS_MODE + BN_CTX *new_ctx = NULL; if (ctx == NULL) - if ((ctx = new_ctx = BN_CTX_new()) == NULL) - return 0; + ctx = new_ctx = BN_CTX_new(); +#endif + if (ctx == 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)) + curve_p = BN_CTX_get(ctx); + curve_a = BN_CTX_get(ctx); + curve_b = BN_CTX_get(ctx); + if (curve_b == NULL) goto err; BN_bin2bn(nistp256_curve_params[0], sizeof(felem_bytearray), curve_p); BN_bin2bn(nistp256_curve_params[1], sizeof(felem_bytearray), curve_a); @@ -1906,8 +1918,9 @@ int ec_GFp_nistp256_group_set_curve(EC_GROUP *group, const BIGNUM *p, 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); +#ifndef FIPS_MODE + BN_CTX_free(new_ctx); +#endif return ret; } @@ -1973,7 +1986,6 @@ static void make_points_affine(size_t num, smallfelem points[][3], sizeof(smallfelem), tmp_smallfelems, (void (*)(void *))smallfelem_one, - (int (*)(const void *)) smallfelem_is_zero_int, (void (*)(void *, const void *)) smallfelem_assign, @@ -2002,14 +2014,13 @@ int ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r, int ret = 0; int j; int mixed = 0; - BN_CTX *new_ctx = NULL; BIGNUM *x, *y, *z, *tmp_scalar; felem_bytearray g_secret; felem_bytearray *secrets = NULL; - smallfelem(*pre_comp)[17][3] = NULL; + smallfelem (*pre_comp)[17][3] = NULL; smallfelem *tmp_smallfelems = NULL; - felem_bytearray tmp; - unsigned i, num_bytes; + unsigned i; + int num_bytes; int have_pre_comp = 0; size_t num_points = num; smallfelem x_in, y_in, z_in; @@ -2020,21 +2031,16 @@ int ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r, 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)) + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + z = BN_CTX_get(ctx); + tmp_scalar = BN_CTX_get(ctx); + if (tmp_scalar == NULL) goto err; if (scalar != NULL) { - pre = EC_EX_DATA_get_data(group->extra_data, - nistp256_pre_comp_dup, - nistp256_pre_comp_free, - nistp256_pre_comp_clear_free); + pre = group->pre_comp.nistp256; if (pre) /* we have precomputation, try to use it */ g_pre_comp = (const smallfelem(*)[16][3])pre->g_pre_comp; @@ -2073,11 +2079,11 @@ int ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r, */ mixed = 1; } - secrets = OPENSSL_malloc(num_points * sizeof(felem_bytearray)); - pre_comp = OPENSSL_malloc(num_points * 17 * 3 * sizeof(smallfelem)); + secrets = OPENSSL_malloc(sizeof(*secrets) * num_points); + pre_comp = OPENSSL_malloc(sizeof(*pre_comp) * num_points); if (mixed) tmp_smallfelems = - OPENSSL_malloc((num_points * 17 + 1) * sizeof(smallfelem)); + OPENSSL_malloc(sizeof(*tmp_smallfelems) * (num_points * 17 + 1)); if ((secrets == NULL) || (pre_comp == NULL) || (mixed && (tmp_smallfelems == NULL))) { ECerr(EC_F_EC_GFP_NISTP256_POINTS_MUL, ERR_R_MALLOC_FAILURE); @@ -2088,20 +2094,18 @@ int ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r, * 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(smallfelem)); + memset(secrets, 0, sizeof(*secrets) * num_points); + memset(pre_comp, 0, sizeof(*pre_comp) * num_points); for (i = 0; i < num_points; ++i) { - if (i == num) + if (i == num) { /* * we didn't have a valid precomputation, so we pick the * generator */ - { p = EC_GROUP_get0_generator(group); p_scalar = scalar; - } else + } else { /* the i^th point */ - { p = points[i]; p_scalar = scalars[i]; } @@ -2117,10 +2121,16 @@ int ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r, ECerr(EC_F_EC_GFP_NISTP256_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); + num_bytes = BN_bn2lebinpad(tmp_scalar, + secrets[i], sizeof(secrets[i])); + } else { + num_bytes = BN_bn2lebinpad(p_scalar, + secrets[i], sizeof(secrets[i])); + } + if (num_bytes < 0) { + ECerr(EC_F_EC_GFP_NISTP256_POINTS_MUL, ERR_R_BN_LIB); + goto err; + } /* precompute multiples */ if ((!BN_to_felem(x_out, p->X)) || (!BN_to_felem(y_out, p->Y)) || @@ -2165,20 +2175,21 @@ int ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r, ECerr(EC_F_EC_GFP_NISTP256_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); + num_bytes = BN_bn2lebinpad(tmp_scalar, g_secret, sizeof(g_secret)); + } else { + num_bytes = BN_bn2lebinpad(scalar, g_secret, sizeof(g_secret)); + } /* do the multiplication with generator precomputation */ batch_mul(x_out, y_out, z_out, (const felem_bytearray(*))secrets, num_points, g_secret, mixed, (const smallfelem(*)[17][3])pre_comp, g_pre_comp); - } else + } else { /* do the multiplication without generator precomputation */ batch_mul(x_out, y_out, z_out, (const felem_bytearray(*))secrets, num_points, NULL, mixed, (const smallfelem(*)[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); @@ -2193,14 +2204,9 @@ int ec_GFp_nistp256_points_mul(const EC_GROUP *group, EC_POINT *r, err: BN_CTX_end(ctx); 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_smallfelems != NULL) - OPENSSL_free(tmp_smallfelems); + OPENSSL_free(secrets); + OPENSSL_free(pre_comp); + OPENSSL_free(tmp_smallfelems); return ret; } @@ -2209,21 +2215,28 @@ int ec_GFp_nistp256_precompute_mult(EC_GROUP *group, BN_CTX *ctx) int ret = 0; NISTP256_PRE_COMP *pre = NULL; int i, j; - BN_CTX *new_ctx = NULL; BIGNUM *x, *y; EC_POINT *generator = NULL; smallfelem tmp_smallfelems[32]; felem x_tmp, y_tmp, z_tmp; +#ifndef FIPS_MODE + BN_CTX *new_ctx = NULL; +#endif /* throw away old precomputation */ - EC_EX_DATA_free_data(&group->extra_data, nistp256_pre_comp_dup, - nistp256_pre_comp_free, - nistp256_pre_comp_clear_free); + EC_pre_comp_free(group); + +#ifndef FIPS_MODE if (ctx == NULL) - if ((ctx = new_ctx = BN_CTX_new()) == NULL) - return 0; + ctx = new_ctx = BN_CTX_new(); +#endif + if (ctx == NULL) + return 0; + BN_CTX_start(ctx); - if (((x = BN_CTX_get(ctx)) == NULL) || ((y = BN_CTX_get(ctx)) == NULL)) + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + if (y == NULL) goto err; /* get the generator */ if (group->generator == NULL) @@ -2233,7 +2246,7 @@ int ec_GFp_nistp256_precompute_mult(EC_GROUP *group, BN_CTX *ctx) goto err; BN_bin2bn(nistp256_curve_params[3], sizeof(felem_bytearray), x); BN_bin2bn(nistp256_curve_params[4], sizeof(felem_bytearray), y); - if (!EC_POINT_set_affine_coordinates_GFp(group, generator, x, y, ctx)) + if (!EC_POINT_set_affine_coordinates(group, generator, x, y, ctx)) goto err; if ((pre = nistp256_pre_comp_new()) == NULL) goto err; @@ -2242,8 +2255,7 @@ int ec_GFp_nistp256_precompute_mult(EC_GROUP *group, BN_CTX *ctx) */ 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; + goto done; } if ((!BN_to_felem(x_tmp, group->generator->X)) || (!BN_to_felem(y_tmp, group->generator->Y)) || @@ -2330,31 +2342,23 @@ int ec_GFp_nistp256_precompute_mult(EC_GROUP *group, BN_CTX *ctx) } make_points_affine(31, &(pre->g_pre_comp[0][1]), tmp_smallfelems); - if (!EC_EX_DATA_set_data(&group->extra_data, pre, nistp256_pre_comp_dup, - nistp256_pre_comp_free, - nistp256_pre_comp_clear_free)) - goto err; - ret = 1; + done: + SETPRECOMP(group, nistp256, pre); pre = NULL; + ret = 1; + err: BN_CTX_end(ctx); EC_POINT_free(generator); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); - nistp256_pre_comp_free(pre); +#ifndef FIPS_MODE + BN_CTX_free(new_ctx); +#endif + EC_nistp256_pre_comp_free(pre); return ret; } int ec_GFp_nistp256_have_precompute_mult(const EC_GROUP *group) { - if (EC_EX_DATA_get_data(group->extra_data, nistp256_pre_comp_dup, - nistp256_pre_comp_free, - nistp256_pre_comp_clear_free) - != NULL) - return 1; - else - return 0; + return HAVEPRECOMP(group, nistp256); } -#else -static void *dummy = &dummy; #endif