1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Glue Code for x86_64/AVX2 assembler optimized version of Serpent
4  *
5  * Copyright © 2012-2013 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
6  */
7 
8 #include <linux/module.h>
9 #include <linux/types.h>
10 #include <linux/crypto.h>
11 #include <linux/err.h>
12 #include <crypto/algapi.h>
13 #include <crypto/internal/simd.h>
14 #include <crypto/serpent.h>
15 
16 #include "serpent-avx.h"
17 #include "ecb_cbc_helpers.h"
18 
19 #define SERPENT_AVX2_PARALLEL_BLOCKS 16
20 
21 /* 16-way AVX2 parallel cipher functions */
22 asmlinkage void serpent_ecb_enc_16way(const void *ctx, u8 *dst, const u8 *src);
23 asmlinkage void serpent_ecb_dec_16way(const void *ctx, u8 *dst, const u8 *src);
24 asmlinkage void serpent_cbc_dec_16way(const void *ctx, u8 *dst, const u8 *src);
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 int ecb_encrypt(struct skcipher_request *req)
33 {
34 	ECB_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
35 	ECB_BLOCK(SERPENT_AVX2_PARALLEL_BLOCKS, serpent_ecb_enc_16way);
36 	ECB_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_ecb_enc_8way_avx);
37 	ECB_BLOCK(1, __serpent_encrypt);
38 	ECB_WALK_END();
39 }
40 
41 static int ecb_decrypt(struct skcipher_request *req)
42 {
43 	ECB_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
44 	ECB_BLOCK(SERPENT_AVX2_PARALLEL_BLOCKS, serpent_ecb_dec_16way);
45 	ECB_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_ecb_dec_8way_avx);
46 	ECB_BLOCK(1, __serpent_decrypt);
47 	ECB_WALK_END();
48 }
49 
50 static int cbc_encrypt(struct skcipher_request *req)
51 {
52 	CBC_WALK_START(req, SERPENT_BLOCK_SIZE, -1);
53 	CBC_ENC_BLOCK(__serpent_encrypt);
54 	CBC_WALK_END();
55 }
56 
57 static int cbc_decrypt(struct skcipher_request *req)
58 {
59 	CBC_WALK_START(req, SERPENT_BLOCK_SIZE, SERPENT_PARALLEL_BLOCKS);
60 	CBC_DEC_BLOCK(SERPENT_AVX2_PARALLEL_BLOCKS, serpent_cbc_dec_16way);
61 	CBC_DEC_BLOCK(SERPENT_PARALLEL_BLOCKS, serpent_cbc_dec_8way_avx);
62 	CBC_DEC_BLOCK(1, __serpent_decrypt);
63 	CBC_WALK_END();
64 }
65 
66 static struct skcipher_alg serpent_algs[] = {
67 	{
68 		.base.cra_name		= "__ecb(serpent)",
69 		.base.cra_driver_name	= "__ecb-serpent-avx2",
70 		.base.cra_priority	= 600,
71 		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
72 		.base.cra_blocksize	= SERPENT_BLOCK_SIZE,
73 		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
74 		.base.cra_module	= THIS_MODULE,
75 		.min_keysize		= SERPENT_MIN_KEY_SIZE,
76 		.max_keysize		= SERPENT_MAX_KEY_SIZE,
77 		.setkey			= serpent_setkey_skcipher,
78 		.encrypt		= ecb_encrypt,
79 		.decrypt		= ecb_decrypt,
80 	}, {
81 		.base.cra_name		= "__cbc(serpent)",
82 		.base.cra_driver_name	= "__cbc-serpent-avx2",
83 		.base.cra_priority	= 600,
84 		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
85 		.base.cra_blocksize	= SERPENT_BLOCK_SIZE,
86 		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
87 		.base.cra_module	= THIS_MODULE,
88 		.min_keysize		= SERPENT_MIN_KEY_SIZE,
89 		.max_keysize		= SERPENT_MAX_KEY_SIZE,
90 		.ivsize			= SERPENT_BLOCK_SIZE,
91 		.setkey			= serpent_setkey_skcipher,
92 		.encrypt		= cbc_encrypt,
93 		.decrypt		= cbc_decrypt,
94 	},
95 };
96 
97 static struct simd_skcipher_alg *serpent_simd_algs[ARRAY_SIZE(serpent_algs)];
98 
99 static int __init init(void)
100 {
101 	const char *feature_name;
102 
103 	if (!boot_cpu_has(X86_FEATURE_AVX2) || !boot_cpu_has(X86_FEATURE_OSXSAVE)) {
104 		pr_info("AVX2 instructions are not detected.\n");
105 		return -ENODEV;
106 	}
107 	if (!cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM,
108 				&feature_name)) {
109 		pr_info("CPU feature '%s' is not supported.\n", feature_name);
110 		return -ENODEV;
111 	}
112 
113 	return simd_register_skciphers_compat(serpent_algs,
114 					      ARRAY_SIZE(serpent_algs),
115 					      serpent_simd_algs);
116 }
117 
118 static void __exit fini(void)
119 {
120 	simd_unregister_skciphers(serpent_algs, ARRAY_SIZE(serpent_algs),
121 				  serpent_simd_algs);
122 }
123 
124 module_init(init);
125 module_exit(fini);
126 
127 MODULE_LICENSE("GPL");
128 MODULE_DESCRIPTION("Serpent Cipher Algorithm, AVX2 optimized");
129 MODULE_ALIAS_CRYPTO("serpent");
130 MODULE_ALIAS_CRYPTO("serpent-asm");
131