3 * The Salsa20 stream cipher.
6 /* nettle, low-level cryptographics library
8 * Copyright (C) 2012 Simon Josefsson
10 * The nettle library is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published by
12 * the Free Software Foundation; either version 2.1 of the License, or (at your
13 * option) any later version.
15 * The nettle library is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
17 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
18 * License for more details.
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with the nettle library; see the file COPYING.LIB. If not, write to
22 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
27 salsa20-ref.c version 20051118
44 salsa20_crypt(struct salsa20_ctx *ctx,
54 uint32_t x[_SALSA20_INPUT_LENGTH];
56 _salsa20_core (x, ctx->input, 20);
58 ctx->input[9] += (++ctx->input[8] == 0);
60 /* stopping at 2^70 length per nonce is user's responsibility */
62 if (length <= SALSA20_BLOCK_SIZE)
64 memxor3 (c, m, (uint8_t *) x, length);
67 memxor3 (c, m, (uint8_t *) x, SALSA20_BLOCK_SIZE);
69 length -= SALSA20_BLOCK_SIZE;
70 c += SALSA20_BLOCK_SIZE;
71 m += SALSA20_BLOCK_SIZE;