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-rw-r--r--crypto/chacha20_generic.c137
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");