/* MIT License * * Copyright (c) 2016-2020 INRIA, CMU and Microsoft Corporation * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include "internal/Hacl_Chacha20.h" const uint32_t Hacl_Impl_Chacha20_Vec_chacha20_constants[4U] = { (uint32_t)0x61707865U, (uint32_t)0x3320646eU, (uint32_t)0x79622d32U, (uint32_t)0x6b206574U }; static inline void quarter_round(uint32_t *st, uint32_t a, uint32_t b, uint32_t c, uint32_t d) { uint32_t sta = st[a]; uint32_t stb0 = st[b]; uint32_t std0 = st[d]; uint32_t sta10 = sta + stb0; uint32_t std10 = std0 ^ sta10; uint32_t std2 = std10 << (uint32_t)16U | std10 >> (uint32_t)16U; st[a] = sta10; st[d] = std2; uint32_t sta0 = st[c]; uint32_t stb1 = st[d]; uint32_t std3 = st[b]; uint32_t sta11 = sta0 + stb1; uint32_t std11 = std3 ^ sta11; uint32_t std20 = std11 << (uint32_t)12U | std11 >> (uint32_t)20U; st[c] = sta11; st[b] = std20; uint32_t sta2 = st[a]; uint32_t stb2 = st[b]; uint32_t std4 = st[d]; uint32_t sta12 = sta2 + stb2; uint32_t std12 = std4 ^ sta12; uint32_t std21 = std12 << (uint32_t)8U | std12 >> (uint32_t)24U; st[a] = sta12; st[d] = std21; uint32_t sta3 = st[c]; uint32_t stb = st[d]; uint32_t std = st[b]; uint32_t sta1 = sta3 + stb; uint32_t std1 = std ^ sta1; uint32_t std22 = std1 << (uint32_t)7U | std1 >> (uint32_t)25U; st[c] = sta1; st[b] = std22; } static inline void double_round(uint32_t *st) { quarter_round(st, (uint32_t)0U, (uint32_t)4U, (uint32_t)8U, (uint32_t)12U); quarter_round(st, (uint32_t)1U, (uint32_t)5U, (uint32_t)9U, (uint32_t)13U); quarter_round(st, (uint32_t)2U, (uint32_t)6U, (uint32_t)10U, (uint32_t)14U); quarter_round(st, (uint32_t)3U, (uint32_t)7U, (uint32_t)11U, (uint32_t)15U); quarter_round(st, (uint32_t)0U, (uint32_t)5U, (uint32_t)10U, (uint32_t)15U); quarter_round(st, (uint32_t)1U, (uint32_t)6U, (uint32_t)11U, (uint32_t)12U); quarter_round(st, (uint32_t)2U, (uint32_t)7U, (uint32_t)8U, (uint32_t)13U); quarter_round(st, (uint32_t)3U, (uint32_t)4U, (uint32_t)9U, (uint32_t)14U); } static inline void rounds(uint32_t *st) { double_round(st); double_round(st); double_round(st); double_round(st); double_round(st); double_round(st); double_round(st); double_round(st); double_round(st); double_round(st); } static inline void chacha20_core(uint32_t *k, uint32_t *ctx, uint32_t ctr) { memcpy(k, ctx, (uint32_t)16U * sizeof (uint32_t)); uint32_t ctr_u32 = ctr; k[12U] = k[12U] + ctr_u32; rounds(k); for (uint32_t i = (uint32_t)0U; i < (uint32_t)16U; i++) { uint32_t *os = k; uint32_t x = k[i] + ctx[i]; os[i] = x; } k[12U] = k[12U] + ctr_u32; } static const uint32_t chacha20_constants[4U] = { (uint32_t)0x61707865U, (uint32_t)0x3320646eU, (uint32_t)0x79622d32U, (uint32_t)0x6b206574U }; static inline void chacha20_init(uint32_t *ctx, uint8_t *k, uint8_t *n, uint32_t ctr) { uint32_t *uu____0 = ctx; for (uint32_t i = (uint32_t)0U; i < (uint32_t)4U; i++) { uint32_t *os = uu____0; uint32_t x = chacha20_constants[i]; os[i] = x; } uint32_t *uu____1 = ctx + (uint32_t)4U; for (uint32_t i = (uint32_t)0U; i < (uint32_t)8U; i++) { uint32_t *os = uu____1; uint8_t *bj = k + i * (uint32_t)4U; uint32_t u = load32_le(bj); uint32_t r = u; uint32_t x = r; os[i] = x; } ctx[12U] = ctr; uint32_t *uu____2 = ctx + (uint32_t)13U; for (uint32_t i = (uint32_t)0U; i < (uint32_t)3U; i++) { uint32_t *os = uu____2; uint8_t *bj = n + i * (uint32_t)4U; uint32_t u = load32_le(bj); uint32_t r = u; uint32_t x = r; os[i] = x; } } static inline void chacha20_encrypt_block(uint32_t *ctx, uint8_t *out, uint32_t incr, uint8_t *text) { uint32_t k[16U] = { 0U }; chacha20_core(k, ctx, incr); uint32_t bl[16U] = { 0U }; for (uint32_t i = (uint32_t)0U; i < (uint32_t)16U; i++) { uint32_t *os = bl; uint8_t *bj = text + i * (uint32_t)4U; uint32_t u = load32_le(bj); uint32_t r = u; uint32_t x = r; os[i] = x; } for (uint32_t i = (uint32_t)0U; i < (uint32_t)16U; i++) { uint32_t *os = bl; uint32_t x = bl[i] ^ k[i]; os[i] = x; } for (uint32_t i = (uint32_t)0U; i < (uint32_t)16U; i++) { store32_le(out + i * (uint32_t)4U, bl[i]); } } static inline void chacha20_encrypt_last(uint32_t *ctx, uint32_t len, uint8_t *out, uint32_t incr, uint8_t *text) { uint8_t plain[64U] = { 0U }; memcpy(plain, text, len * sizeof (uint8_t)); chacha20_encrypt_block(ctx, plain, incr, plain); memcpy(out, plain, len * sizeof (uint8_t)); } static inline void chacha20_update(uint32_t *ctx, uint32_t len, uint8_t *out, uint8_t *text) { uint32_t rem = len % (uint32_t)64U; uint32_t nb = len / (uint32_t)64U; uint32_t rem1 = len % (uint32_t)64U; for (uint32_t i = (uint32_t)0U; i < nb; i++) { chacha20_encrypt_block(ctx, out + i * (uint32_t)64U, i, text + i * (uint32_t)64U); } if (rem1 > (uint32_t)0U) { chacha20_encrypt_last(ctx, rem, out + nb * (uint32_t)64U, nb, text + nb * (uint32_t)64U); } } void Hacl_Chacha20_chacha20_encrypt( uint32_t len, uint8_t *out, uint8_t *text, uint8_t *key, uint8_t *n, uint32_t ctr ) { uint32_t ctx[16U] = { 0U }; chacha20_init(ctx, key, n, ctr); chacha20_update(ctx, len, out, text); } void Hacl_Chacha20_chacha20_decrypt( uint32_t len, uint8_t *out, uint8_t *cipher, uint8_t *key, uint8_t *n, uint32_t ctr ) { uint32_t ctx[16U] = { 0U }; chacha20_init(ctx, key, n, ctr); chacha20_update(ctx, len, out, cipher); }