1*66bae5e7Schristos /* 2*66bae5e7Schristos * Copyright 2017-2021 The OpenSSL Project Authors. All Rights Reserved. 3*66bae5e7Schristos * Copyright 2014 Cryptography Research, Inc. 4*66bae5e7Schristos * 5*66bae5e7Schristos * Licensed under the Apache License 2.0 (the "License"). You may not use 6*66bae5e7Schristos * this file except in compliance with the License. You can obtain a copy 7*66bae5e7Schristos * in the file LICENSE in the source distribution or at 8*66bae5e7Schristos * https://www.openssl.org/source/license.html 9*66bae5e7Schristos * 10*66bae5e7Schristos * Originally written by Mike Hamburg 11*66bae5e7Schristos */ 12*66bae5e7Schristos 13*66bae5e7Schristos #include "e_os.h" 14*66bae5e7Schristos #include <openssl/macros.h> 15*66bae5e7Schristos #include "internal/numbers.h" 16*66bae5e7Schristos 17*66bae5e7Schristos #ifdef UINT128_MAX 18*66bae5e7Schristos /* We have support for 128 bit ints, so do nothing here */ 19*66bae5e7Schristos NON_EMPTY_TRANSLATION_UNIT 20*66bae5e7Schristos #else 21*66bae5e7Schristos 22*66bae5e7Schristos # include "../field.h" 23*66bae5e7Schristos 24*66bae5e7Schristos void gf_mul(gf_s * RESTRICT cs, const gf as, const gf bs) 25*66bae5e7Schristos { 26*66bae5e7Schristos const uint32_t *a = as->limb, *b = bs->limb; 27*66bae5e7Schristos uint32_t *c = cs->limb; 28*66bae5e7Schristos uint64_t accum0 = 0, accum1 = 0, accum2 = 0; 29*66bae5e7Schristos uint32_t mask = (1 << 28) - 1; 30*66bae5e7Schristos uint32_t aa[8], bb[8]; 31*66bae5e7Schristos int i, j; 32*66bae5e7Schristos 33*66bae5e7Schristos for (i = 0; i < 8; i++) { 34*66bae5e7Schristos aa[i] = a[i] + a[i + 8]; 35*66bae5e7Schristos bb[i] = b[i] + b[i + 8]; 36*66bae5e7Schristos } 37*66bae5e7Schristos 38*66bae5e7Schristos for (j = 0; j < 8; j++) { 39*66bae5e7Schristos accum2 = 0; 40*66bae5e7Schristos for (i = 0; i < j + 1; i++) { 41*66bae5e7Schristos accum2 += widemul(a[j - i], b[i]); 42*66bae5e7Schristos accum1 += widemul(aa[j - i], bb[i]); 43*66bae5e7Schristos accum0 += widemul(a[8 + j - i], b[8 + i]); 44*66bae5e7Schristos } 45*66bae5e7Schristos accum1 -= accum2; 46*66bae5e7Schristos accum0 += accum2; 47*66bae5e7Schristos accum2 = 0; 48*66bae5e7Schristos for (i = j + 1; i < 8; i++) { 49*66bae5e7Schristos accum0 -= widemul(a[8 + j - i], b[i]); 50*66bae5e7Schristos accum2 += widemul(aa[8 + j - i], bb[i]); 51*66bae5e7Schristos accum1 += widemul(a[16 + j - i], b[8 + i]); 52*66bae5e7Schristos } 53*66bae5e7Schristos accum1 += accum2; 54*66bae5e7Schristos accum0 += accum2; 55*66bae5e7Schristos c[j] = ((uint32_t)(accum0)) & mask; 56*66bae5e7Schristos c[j + 8] = ((uint32_t)(accum1)) & mask; 57*66bae5e7Schristos accum0 >>= 28; 58*66bae5e7Schristos accum1 >>= 28; 59*66bae5e7Schristos } 60*66bae5e7Schristos 61*66bae5e7Schristos accum0 += accum1; 62*66bae5e7Schristos accum0 += c[8]; 63*66bae5e7Schristos accum1 += c[0]; 64*66bae5e7Schristos c[8] = ((uint32_t)(accum0)) & mask; 65*66bae5e7Schristos c[0] = ((uint32_t)(accum1)) & mask; 66*66bae5e7Schristos 67*66bae5e7Schristos accum0 >>= 28; 68*66bae5e7Schristos accum1 >>= 28; 69*66bae5e7Schristos c[9] += ((uint32_t)(accum0)); 70*66bae5e7Schristos c[1] += ((uint32_t)(accum1)); 71*66bae5e7Schristos } 72*66bae5e7Schristos 73*66bae5e7Schristos void gf_mulw_unsigned(gf_s * RESTRICT cs, const gf as, uint32_t b) 74*66bae5e7Schristos { 75*66bae5e7Schristos const uint32_t *a = as->limb; 76*66bae5e7Schristos uint32_t *c = cs->limb; 77*66bae5e7Schristos uint64_t accum0 = 0, accum8 = 0; 78*66bae5e7Schristos uint32_t mask = (1 << 28) - 1; 79*66bae5e7Schristos int i; 80*66bae5e7Schristos 81*66bae5e7Schristos assert(b <= mask); 82*66bae5e7Schristos 83*66bae5e7Schristos for (i = 0; i < 8; i++) { 84*66bae5e7Schristos accum0 += widemul(b, a[i]); 85*66bae5e7Schristos accum8 += widemul(b, a[i + 8]); 86*66bae5e7Schristos c[i] = accum0 & mask; 87*66bae5e7Schristos accum0 >>= 28; 88*66bae5e7Schristos c[i + 8] = accum8 & mask; 89*66bae5e7Schristos accum8 >>= 28; 90*66bae5e7Schristos } 91*66bae5e7Schristos 92*66bae5e7Schristos accum0 += accum8 + c[8]; 93*66bae5e7Schristos c[8] = ((uint32_t)accum0) & mask; 94*66bae5e7Schristos c[9] += (uint32_t)(accum0 >> 28); 95*66bae5e7Schristos 96*66bae5e7Schristos accum8 += c[0]; 97*66bae5e7Schristos c[0] = ((uint32_t)accum8) & mask; 98*66bae5e7Schristos c[1] += (uint32_t)(accum8 >> 28); 99*66bae5e7Schristos } 100*66bae5e7Schristos 101*66bae5e7Schristos void gf_sqr(gf_s * RESTRICT cs, const gf as) 102*66bae5e7Schristos { 103*66bae5e7Schristos gf_mul(cs, as, as); /* Performs better with a dedicated square */ 104*66bae5e7Schristos } 105*66bae5e7Schristos #endif 106