1 /* 2 * Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved. 3 * Copyright 2014 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 HEADER_WORD_H 14 # define HEADER_WORD_H 15 16 # include <string.h> 17 # include <assert.h> 18 # include <stdlib.h> 19 # include <openssl/e_os2.h> 20 # include "arch_intrinsics.h" 21 # include "curve448utils.h" 22 23 # if (ARCH_WORD_BITS == 64) 24 typedef uint64_t word_t, mask_t; 25 typedef __uint128_t dword_t; 26 typedef int32_t hsword_t; 27 typedef int64_t sword_t; 28 typedef __int128_t dsword_t; 29 # elif (ARCH_WORD_BITS == 32) 30 typedef uint32_t word_t, mask_t; 31 typedef uint64_t dword_t; 32 typedef int16_t hsword_t; 33 typedef int32_t sword_t; 34 typedef int64_t dsword_t; 35 # else 36 # error "For now, we only support 32- and 64-bit architectures." 37 # endif 38 39 /* 40 * Scalar limbs are keyed off of the API word size instead of the arch word 41 * size. 42 */ 43 # if C448_WORD_BITS == 64 44 # define SC_LIMB(x) (x) 45 # elif C448_WORD_BITS == 32 46 # define SC_LIMB(x) ((uint32_t)(x)),((x) >> 32) 47 # else 48 # error "For now we only support 32- and 64-bit architectures." 49 # endif 50 51 /* 52 * The plan on booleans: The external interface uses c448_bool_t, but this 53 * might be a different size than our particular arch's word_t (and thus 54 * mask_t). Also, the caller isn't guaranteed to pass it as nonzero. So 55 * bool_to_mask converts word sizes and checks nonzero. On the flip side, 56 * mask_t is always -1 or 0, but it might be a different size than 57 * c448_bool_t. On the third hand, we have success vs boolean types, but 58 * that's handled in common.h: it converts between c448_bool_t and 59 * c448_error_t. 60 */ 61 static ossl_inline c448_bool_t mask_to_bool(mask_t m) 62 { 63 return (c448_sword_t)(sword_t)m; 64 } 65 66 static ossl_inline mask_t bool_to_mask(c448_bool_t m) 67 { 68 /* On most arches this will be optimized to a simple cast. */ 69 mask_t ret = 0; 70 unsigned int i; 71 unsigned int limit = sizeof(c448_bool_t) / sizeof(mask_t); 72 73 if (limit < 1) 74 limit = 1; 75 for (i = 0; i < limit; i++) 76 ret |= ~word_is_zero(m >> (i * 8 * sizeof(word_t))); 77 78 return ret; 79 } 80 81 #endif /* HEADER_WORD_H */ 82