diff options
Diffstat (limited to 'crypto/chacha20_generic.c')
-rw-r--r-- | crypto/chacha20_generic.c | 137 |
1 files changed, 0 insertions, 137 deletions
diff --git a/crypto/chacha20_generic.c b/crypto/chacha20_generic.c deleted file mode 100644 index 3ae96587caf9..000000000000 --- a/crypto/chacha20_generic.c +++ /dev/null @@ -1,137 +0,0 @@ -/* - * ChaCha20 256-bit cipher algorithm, RFC7539 - * - * Copyright (C) 2015 Martin Willi - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - */ - -#include <asm/unaligned.h> -#include <crypto/algapi.h> -#include <crypto/chacha20.h> -#include <crypto/internal/skcipher.h> -#include <linux/module.h> - -static void chacha20_docrypt(u32 *state, u8 *dst, const u8 *src, - unsigned int bytes) -{ - /* aligned to potentially speed up crypto_xor() */ - u8 stream[CHACHA20_BLOCK_SIZE] __aligned(sizeof(long)); - - if (dst != src) - memcpy(dst, src, bytes); - - while (bytes >= CHACHA20_BLOCK_SIZE) { - chacha20_block(state, stream); - crypto_xor(dst, stream, CHACHA20_BLOCK_SIZE); - bytes -= CHACHA20_BLOCK_SIZE; - dst += CHACHA20_BLOCK_SIZE; - } - if (bytes) { - chacha20_block(state, stream); - crypto_xor(dst, stream, bytes); - } -} - -void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv) -{ - state[0] = 0x61707865; /* "expa" */ - state[1] = 0x3320646e; /* "nd 3" */ - state[2] = 0x79622d32; /* "2-by" */ - state[3] = 0x6b206574; /* "te k" */ - state[4] = ctx->key[0]; - state[5] = ctx->key[1]; - state[6] = ctx->key[2]; - state[7] = ctx->key[3]; - state[8] = ctx->key[4]; - state[9] = ctx->key[5]; - state[10] = ctx->key[6]; - state[11] = ctx->key[7]; - state[12] = get_unaligned_le32(iv + 0); - state[13] = get_unaligned_le32(iv + 4); - state[14] = get_unaligned_le32(iv + 8); - state[15] = get_unaligned_le32(iv + 12); -} -EXPORT_SYMBOL_GPL(crypto_chacha20_init); - -int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, - unsigned int keysize) -{ - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); - int i; - - if (keysize != CHACHA20_KEY_SIZE) - return -EINVAL; - - for (i = 0; i < ARRAY_SIZE(ctx->key); i++) - ctx->key[i] = get_unaligned_le32(key + i * sizeof(u32)); - - return 0; -} -EXPORT_SYMBOL_GPL(crypto_chacha20_setkey); - -int crypto_chacha20_crypt(struct skcipher_request *req) -{ - struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); - struct skcipher_walk walk; - u32 state[16]; - int err; - - err = skcipher_walk_virt(&walk, req, true); - - crypto_chacha20_init(state, ctx, walk.iv); - - while (walk.nbytes > 0) { - unsigned int nbytes = walk.nbytes; - - if (nbytes < walk.total) - nbytes = round_down(nbytes, walk.stride); - - chacha20_docrypt(state, walk.dst.virt.addr, walk.src.virt.addr, - nbytes); - err = skcipher_walk_done(&walk, walk.nbytes - nbytes); - } - - return err; -} -EXPORT_SYMBOL_GPL(crypto_chacha20_crypt); - -static struct skcipher_alg alg = { - .base.cra_name = "chacha20", - .base.cra_driver_name = "chacha20-generic", - .base.cra_priority = 100, - .base.cra_blocksize = 1, - .base.cra_ctxsize = sizeof(struct chacha20_ctx), - .base.cra_module = THIS_MODULE, - - .min_keysize = CHACHA20_KEY_SIZE, - .max_keysize = CHACHA20_KEY_SIZE, - .ivsize = CHACHA20_IV_SIZE, - .chunksize = CHACHA20_BLOCK_SIZE, - .setkey = crypto_chacha20_setkey, - .encrypt = crypto_chacha20_crypt, - .decrypt = crypto_chacha20_crypt, -}; - -static int __init chacha20_generic_mod_init(void) -{ - return crypto_register_skcipher(&alg); -} - -static void __exit chacha20_generic_mod_fini(void) -{ - crypto_unregister_skcipher(&alg); -} - -module_init(chacha20_generic_mod_init); -module_exit(chacha20_generic_mod_fini); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Martin Willi <martin@strongswan.org>"); -MODULE_DESCRIPTION("chacha20 cipher algorithm"); -MODULE_ALIAS_CRYPTO("chacha20"); -MODULE_ALIAS_CRYPTO("chacha20-generic"); |