| /* |
| * Copyright 2017-2021 The OpenSSL Project Authors. All Rights Reserved. |
| * Copyright 2014 Cryptography Research, Inc. |
| * |
| * 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 |
| * |
| * Originally written by Mike Hamburg |
| */ |
| |
| #include "internal/e_os.h" |
| #include <openssl/macros.h> |
| #include "internal/numbers.h" |
| |
| #ifdef UINT128_MAX |
| /* We have support for 128 bit ints, so do nothing here */ |
| NON_EMPTY_TRANSLATION_UNIT |
| #else |
| |
| # include "../field.h" |
| |
| void gf_mul(gf_s * RESTRICT cs, const gf as, const gf bs) |
| { |
| const uint32_t *a = as->limb, *b = bs->limb; |
| uint32_t *c = cs->limb; |
| uint64_t accum0 = 0, accum1 = 0, accum2 = 0; |
| uint32_t mask = (1 << 28) - 1; |
| uint32_t aa[8], bb[8]; |
| int i, j; |
| |
| for (i = 0; i < 8; i++) { |
| aa[i] = a[i] + a[i + 8]; |
| bb[i] = b[i] + b[i + 8]; |
| } |
| |
| for (j = 0; j < 8; j++) { |
| accum2 = 0; |
| for (i = 0; i < j + 1; i++) { |
| accum2 += widemul(a[j - i], b[i]); |
| accum1 += widemul(aa[j - i], bb[i]); |
| accum0 += widemul(a[8 + j - i], b[8 + i]); |
| } |
| accum1 -= accum2; |
| accum0 += accum2; |
| accum2 = 0; |
| for (i = j + 1; i < 8; i++) { |
| accum0 -= widemul(a[8 + j - i], b[i]); |
| accum2 += widemul(aa[8 + j - i], bb[i]); |
| accum1 += widemul(a[16 + j - i], b[8 + i]); |
| } |
| accum1 += accum2; |
| accum0 += accum2; |
| c[j] = ((uint32_t)(accum0)) & mask; |
| c[j + 8] = ((uint32_t)(accum1)) & mask; |
| accum0 >>= 28; |
| accum1 >>= 28; |
| } |
| |
| accum0 += accum1; |
| accum0 += c[8]; |
| accum1 += c[0]; |
| c[8] = ((uint32_t)(accum0)) & mask; |
| c[0] = ((uint32_t)(accum1)) & mask; |
| |
| accum0 >>= 28; |
| accum1 >>= 28; |
| c[9] += ((uint32_t)(accum0)); |
| c[1] += ((uint32_t)(accum1)); |
| } |
| |
| void gf_mulw_unsigned(gf_s * RESTRICT cs, const gf as, uint32_t b) |
| { |
| const uint32_t *a = as->limb; |
| uint32_t *c = cs->limb; |
| uint64_t accum0 = 0, accum8 = 0; |
| uint32_t mask = (1 << 28) - 1; |
| int i; |
| |
| assert(b <= mask); |
| |
| for (i = 0; i < 8; i++) { |
| accum0 += widemul(b, a[i]); |
| accum8 += widemul(b, a[i + 8]); |
| c[i] = accum0 & mask; |
| accum0 >>= 28; |
| c[i + 8] = accum8 & mask; |
| accum8 >>= 28; |
| } |
| |
| accum0 += accum8 + c[8]; |
| c[8] = ((uint32_t)accum0) & mask; |
| c[9] += (uint32_t)(accum0 >> 28); |
| |
| accum8 += c[0]; |
| c[0] = ((uint32_t)accum8) & mask; |
| c[1] += (uint32_t)(accum8 >> 28); |
| } |
| |
| void gf_sqr(gf_s * RESTRICT cs, const gf as) |
| { |
| gf_mul(cs, as, as); /* Performs better with a dedicated square */ |
| } |
| #endif |