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/internal/simd.h>
22 #include <crypto/serpent.h>
23 
24 #include "serpent-sse2.h"
25 #include "ecb_cbc_helpers.h"
26 
serpent_setkey_skcipher(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)27 static int serpent_setkey_skcipher(struct crypto_skcipher *tfm,
28 				   const u8 *key, unsigned int keylen)
29 {
30 	return __serpent_setkey(crypto_skcipher_ctx(tfm), key, keylen);
31 }
32 
serpent_decrypt_cbc_xway(const void * ctx,u8 * dst,const u8 * src)33 static void serpent_decrypt_cbc_xway(const void *ctx, u8 *dst, const u8 *src)
34 {
35 	u8 buf[SERPENT_PARALLEL_BLOCKS - 1][SERPENT_BLOCK_SIZE];
36 	const u8 *s = src;
37 
38 	if (dst == src)
39 		s = memcpy(buf, src, sizeof(buf));
40 	serpent_dec_blk_xway(ctx, dst, src);
41 	crypto_xor(dst + SERPENT_BLOCK_SIZE, s, sizeof(buf));
42 }
43 
ecb_encrypt(struct skcipher_request * req)44 static int ecb_encrypt(struct skcipher_request *req)
45 {
46 	ECB_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
47 	ECB_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_enc_blk_xway);
48 	ECB_BLOCK(1, __serpent_encrypt);
49 	ECB_WALK_END();
50 }
51 
ecb_decrypt(struct skcipher_request * req)52 static int ecb_decrypt(struct skcipher_request *req)
53 {
54 	ECB_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
55 	ECB_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_dec_blk_xway);
56 	ECB_BLOCK(1, __serpent_decrypt);
57 	ECB_WALK_END();
58 }
59 
cbc_encrypt(struct skcipher_request * req)60 static int cbc_encrypt(struct skcipher_request *req)
61 {
62 	CBC_WALK_START(req, SERPENT_BLOCK_SIZE, -1);
63 	CBC_ENC_BLOCK(__serpent_encrypt);
64 	CBC_WALK_END();
65 }
66 
cbc_decrypt(struct skcipher_request * req)67 static int cbc_decrypt(struct skcipher_request *req)
68 {
69 	CBC_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
70 	CBC_DEC_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_decrypt_cbc_xway);
71 	CBC_DEC_BLOCK(1, __serpent_decrypt);
72 	CBC_WALK_END();
73 }
74 
75 static struct skcipher_alg serpent_algs[] = {
76 	{
77 		.base.cra_name		= "__ecb(serpent)",
78 		.base.cra_driver_name	= "__ecb-serpent-sse2",
79 		.base.cra_priority	= 400,
80 		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
81 		.base.cra_blocksize	= SERPENT_BLOCK_SIZE,
82 		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
83 		.base.cra_module	= THIS_MODULE,
84 		.min_keysize		= SERPENT_MIN_KEY_SIZE,
85 		.max_keysize		= SERPENT_MAX_KEY_SIZE,
86 		.setkey			= serpent_setkey_skcipher,
87 		.encrypt		= ecb_encrypt,
88 		.decrypt		= ecb_decrypt,
89 	}, {
90 		.base.cra_name		= "__cbc(serpent)",
91 		.base.cra_driver_name	= "__cbc-serpent-sse2",
92 		.base.cra_priority	= 400,
93 		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
94 		.base.cra_blocksize	= SERPENT_BLOCK_SIZE,
95 		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
96 		.base.cra_module	= THIS_MODULE,
97 		.min_keysize		= SERPENT_MIN_KEY_SIZE,
98 		.max_keysize		= SERPENT_MAX_KEY_SIZE,
99 		.ivsize			= SERPENT_BLOCK_SIZE,
100 		.setkey			= serpent_setkey_skcipher,
101 		.encrypt		= cbc_encrypt,
102 		.decrypt		= cbc_decrypt,
103 	},
104 };
105 
106 static struct simd_skcipher_alg *serpent_simd_algs[ARRAY_SIZE(serpent_algs)];
107 
serpent_sse2_init(void)108 static int __init serpent_sse2_init(void)
109 {
110 	if (!boot_cpu_has(X86_FEATURE_XMM2)) {
111 		printk(KERN_INFO "SSE2 instructions are not detected.\n");
112 		return -ENODEV;
113 	}
114 
115 	return simd_register_skciphers_compat(serpent_algs,
116 					      ARRAY_SIZE(serpent_algs),
117 					      serpent_simd_algs);
118 }
119 
serpent_sse2_exit(void)120 static void __exit serpent_sse2_exit(void)
121 {
122 	simd_unregister_skciphers(serpent_algs, ARRAY_SIZE(serpent_algs),
123 				  serpent_simd_algs);
124 }
125 
126 module_init(serpent_sse2_init);
127 module_exit(serpent_sse2_exit);
128 
129 MODULE_DESCRIPTION("Serpent Cipher Algorithm, SSE2 optimized");
130 MODULE_LICENSE("GPL");
131 MODULE_ALIAS_CRYPTO("serpent");
132