1 /* 2 * Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved. 3 * Copyright 2014-2016 Cryptography Research, Inc. 4 * 5 * Licensed under the OpenSSL license (the "License"). You may not use 6 * this file except in compliance with the License. You can obtain a copy 7 * in the file LICENSE in the source distribution or at 8 * https://www.openssl.org/source/license.html 9 * 10 * Originally written by Mike Hamburg 11 */ 12 13 #ifndef OSSL_CRYPTO_EC_CURVE448_ARCH_32_F_IMPL_H 14 # define OSSL_CRYPTO_EC_CURVE448_ARCH_32_F_IMPL_H 15 16 # define GF_HEADROOM 2 17 # define LIMB(x) ((x) & ((1 << 28) - 1)), ((x) >> 28) 18 # define FIELD_LITERAL(a, b, c, d, e, f, g, h) \ 19 {{LIMB(a), LIMB(b), LIMB(c), LIMB(d), LIMB(e), LIMB(f), LIMB(g), LIMB(h)}} 20 21 # define LIMB_PLACE_VALUE(i) 28 22 23 void gf_add_RAW(gf out, const gf a, const gf b) 24 { 25 unsigned int i; 26 27 for (i = 0; i < NLIMBS; i++) 28 out->limb[i] = a->limb[i] + b->limb[i]; 29 } 30 31 void gf_sub_RAW(gf out, const gf a, const gf b) 32 { 33 unsigned int i; 34 35 for (i = 0; i < NLIMBS; i++) 36 out->limb[i] = a->limb[i] - b->limb[i]; 37 } 38 39 void gf_bias(gf a, int amt) 40 { 41 unsigned int i; 42 uint32_t co1 = ((1 << 28) - 1) * amt, co2 = co1 - amt; 43 44 for (i = 0; i < NLIMBS; i++) 45 a->limb[i] += (i == NLIMBS / 2) ? co2 : co1; 46 } 47 48 void gf_weak_reduce(gf a) 49 { 50 uint32_t mask = (1 << 28) - 1; 51 uint32_t tmp = a->limb[NLIMBS - 1] >> 28; 52 unsigned int i; 53 54 a->limb[NLIMBS / 2] += tmp; 55 for (i = NLIMBS - 1; i > 0; i--) 56 a->limb[i] = (a->limb[i] & mask) + (a->limb[i - 1] >> 28); 57 a->limb[0] = (a->limb[0] & mask) + tmp; 58 } 59 60 #endif /* OSSL_CRYPTO_EC_CURVE448_ARCH_32_F_IMPL_H */ 61