xref: /linux/arch/x86/crypto/serpent_sse2_glue.c (revision fb7399cf2d0b33825b8039f95c45395c7deba25c)
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 
26 static 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 
32 static 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 
43 static 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 
51 static 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 
59 static 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 
66 static 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 
74 static 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 
103 static 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 
114 static void __exit serpent_sse2_exit(void)
115 {
116 	crypto_unregister_skciphers(serpent_algs, ARRAY_SIZE(serpent_algs));
117 }
118 
119 module_init(serpent_sse2_init);
120 module_exit(serpent_sse2_exit);
121 
122 MODULE_DESCRIPTION("Serpent Cipher Algorithm, SSE2 optimized");
123 MODULE_LICENSE("GPL");
124 MODULE_ALIAS_CRYPTO("serpent");
125