serpent_sse2_glue.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Glue Code for SSE2 assembler versions of Serpent Cipher
  4 *
  5 * Copyright (c) 2011 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
  6 *
  7 * Glue code based on aesni-intel_glue.c by:
  8 *  Copyright (C) 2008, Intel Corp.
  9 *    Author: Huang Ying <ying.huang@intel.com>
 10 *
 11 * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by:
 12 *   Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
 13 */
 14
 15#include <linux/module.h>
 16#include <linux/types.h>
 17#include <linux/crypto.h>
 18#include <linux/err.h>
 19#include <crypto/algapi.h>
 20#include <crypto/b128ops.h>
 21#include <crypto/serpent.h>
 22
 23#include "serpent-sse2.h"
 24#include "ecb_cbc_helpers.h"
 25
 26static int serpent_setkey_skcipher(struct crypto_skcipher *tfm,
 27				   const u8 *key, unsigned int keylen)
 28{
 29	return __serpent_setkey(crypto_skcipher_ctx(tfm), key, keylen);
 30}
 31
 32static void serpent_decrypt_cbc_xway(const void *ctx, u8 *dst, const u8 *src)
 33{
 34	u8 buf[SERPENT_PARALLEL_BLOCKS - 1][SERPENT_BLOCK_SIZE];
 35	const u8 *s = src;
 36
 37	if (dst == src)
 38		s = memcpy(buf, src, sizeof(buf));
 39	serpent_dec_blk_xway(ctx, dst, src);
 40	crypto_xor(dst + SERPENT_BLOCK_SIZE, s, sizeof(buf));
 41}
 42
 43static int ecb_encrypt(struct skcipher_request *req)
 44{
 45	ECB_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
 46	ECB_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_enc_blk_xway);
 47	ECB_BLOCK(1, __serpent_encrypt);
 48	ECB_WALK_END();
 49}
 50
 51static int ecb_decrypt(struct skcipher_request *req)
 52{
 53	ECB_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
 54	ECB_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_dec_blk_xway);
 55	ECB_BLOCK(1, __serpent_decrypt);
 56	ECB_WALK_END();
 57}
 58
 59static int cbc_encrypt(struct skcipher_request *req)
 60{
 61	CBC_WALK_START(req, SERPENT_BLOCK_SIZE, -1);
 62	CBC_ENC_BLOCK(__serpent_encrypt);
 63	CBC_WALK_END();
 64}
 65
 66static int cbc_decrypt(struct skcipher_request *req)
 67{
 68	CBC_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
 69	CBC_DEC_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_decrypt_cbc_xway);
 70	CBC_DEC_BLOCK(1, __serpent_decrypt);
 71	CBC_WALK_END();
 72}
 73
 74static struct skcipher_alg serpent_algs[] = {
 75	{
 76		.base.cra_name		= "ecb(serpent)",
 77		.base.cra_driver_name	= "ecb-serpent-sse2",
 78		.base.cra_priority	= 400,
 79		.base.cra_blocksize	= SERPENT_BLOCK_SIZE,
 80		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
 81		.base.cra_module	= THIS_MODULE,
 82		.min_keysize		= SERPENT_MIN_KEY_SIZE,
 83		.max_keysize		= SERPENT_MAX_KEY_SIZE,
 84		.setkey			= serpent_setkey_skcipher,
 85		.encrypt		= ecb_encrypt,
 86		.decrypt		= ecb_decrypt,
 87	}, {
 88		.base.cra_name		= "cbc(serpent)",
 89		.base.cra_driver_name	= "cbc-serpent-sse2",
 90		.base.cra_priority	= 400,
 91		.base.cra_blocksize	= SERPENT_BLOCK_SIZE,
 92		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
 93		.base.cra_module	= THIS_MODULE,
 94		.min_keysize		= SERPENT_MIN_KEY_SIZE,
 95		.max_keysize		= SERPENT_MAX_KEY_SIZE,
 96		.ivsize			= SERPENT_BLOCK_SIZE,
 97		.setkey			= serpent_setkey_skcipher,
 98		.encrypt		= cbc_encrypt,
 99		.decrypt		= cbc_decrypt,
100	},
101};
102
103static int __init serpent_sse2_init(void)
104{
105	if (!boot_cpu_has(X86_FEATURE_XMM2)) {
106		printk(KERN_INFO "SSE2 instructions are not detected.\n");
107		return -ENODEV;
108	}
109
110	return crypto_register_skciphers(serpent_algs,
111					 ARRAY_SIZE(serpent_algs));
112}
113
114static void __exit serpent_sse2_exit(void)
115{
116	crypto_unregister_skciphers(serpent_algs, ARRAY_SIZE(serpent_algs));
117}
118
119module_init(serpent_sse2_init);
120module_exit(serpent_sse2_exit);
121
122MODULE_DESCRIPTION("Serpent Cipher Algorithm, SSE2 optimized");
123MODULE_LICENSE("GPL");
124MODULE_ALIAS_CRYPTO("serpent");