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 * CTR part based on code (crypto/ctr.c) by:
14 *   (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
15 */
16
17#include <linux/module.h>
18#include <linux/types.h>
19#include <linux/crypto.h>
20#include <linux/err.h>
21#include <crypto/algapi.h>
22#include <crypto/b128ops.h>
23#include <crypto/internal/simd.h>
24#include <crypto/serpent.h>
25#include <asm/crypto/serpent-sse2.h>
26#include <asm/crypto/glue_helper.h>
27
28static int serpent_setkey_skcipher(struct crypto_skcipher *tfm,
29				   const u8 *key, unsigned int keylen)
30{
31	return __serpent_setkey(crypto_skcipher_ctx(tfm), key, keylen);
32}
33
34static void serpent_decrypt_cbc_xway(const void *ctx, u8 *d, const u8 *s)
35{
36	u128 ivs[SERPENT_PARALLEL_BLOCKS - 1];
37	u128 *dst = (u128 *)d;
38	const u128 *src = (const u128 *)s;
39	unsigned int j;
40
41	for (j = 0; j < SERPENT_PARALLEL_BLOCKS - 1; j++)
42		ivs[j] = src[j];
43
44	serpent_dec_blk_xway(ctx, (u8 *)dst, (u8 *)src);
45
46	for (j = 0; j < SERPENT_PARALLEL_BLOCKS - 1; j++)
47		u128_xor(dst + (j + 1), dst + (j + 1), ivs + j);
48}
49
50static void serpent_crypt_ctr(const void *ctx, u8 *d, const u8 *s, le128 *iv)
51{
52	be128 ctrblk;
53	u128 *dst = (u128 *)d;
54	const u128 *src = (const u128 *)s;
55
56	le128_to_be128(&ctrblk, iv);
57	le128_inc(iv);
58
59	__serpent_encrypt(ctx, (u8 *)&ctrblk, (u8 *)&ctrblk);
60	u128_xor(dst, src, (u128 *)&ctrblk);
61}
62
63static void serpent_crypt_ctr_xway(const void *ctx, u8 *d, const u8 *s,
64				   le128 *iv)
65{
66	be128 ctrblks[SERPENT_PARALLEL_BLOCKS];
67	u128 *dst = (u128 *)d;
68	const u128 *src = (const u128 *)s;
69	unsigned int i;
70
71	for (i = 0; i < SERPENT_PARALLEL_BLOCKS; i++) {
72		if (dst != src)
73			dst[i] = src[i];
74
75		le128_to_be128(&ctrblks[i], iv);
76		le128_inc(iv);
77	}
78
79	serpent_enc_blk_xway_xor(ctx, (u8 *)dst, (u8 *)ctrblks);
80}
81
82static const struct common_glue_ctx serpent_enc = {
83	.num_funcs = 2,
84	.fpu_blocks_limit = SERPENT_PARALLEL_BLOCKS,
85
86	.funcs = { {
87		.num_blocks = SERPENT_PARALLEL_BLOCKS,
88		.fn_u = { .ecb = serpent_enc_blk_xway }
89	}, {
90		.num_blocks = 1,
91		.fn_u = { .ecb = __serpent_encrypt }
92	} }
93};
94
95static const struct common_glue_ctx serpent_ctr = {
96	.num_funcs = 2,
97	.fpu_blocks_limit = SERPENT_PARALLEL_BLOCKS,
98
99	.funcs = { {
100		.num_blocks = SERPENT_PARALLEL_BLOCKS,
101		.fn_u = { .ctr = serpent_crypt_ctr_xway }
102	}, {
103		.num_blocks = 1,
104		.fn_u = { .ctr = serpent_crypt_ctr }
105	} }
106};
107
108static const struct common_glue_ctx serpent_dec = {
109	.num_funcs = 2,
110	.fpu_blocks_limit = SERPENT_PARALLEL_BLOCKS,
111
112	.funcs = { {
113		.num_blocks = SERPENT_PARALLEL_BLOCKS,
114		.fn_u = { .ecb = serpent_dec_blk_xway }
115	}, {
116		.num_blocks = 1,
117		.fn_u = { .ecb = __serpent_decrypt }
118	} }
119};
120
121static const struct common_glue_ctx serpent_dec_cbc = {
122	.num_funcs = 2,
123	.fpu_blocks_limit = SERPENT_PARALLEL_BLOCKS,
124
125	.funcs = { {
126		.num_blocks = SERPENT_PARALLEL_BLOCKS,
127		.fn_u = { .cbc = serpent_decrypt_cbc_xway }
128	}, {
129		.num_blocks = 1,
130		.fn_u = { .cbc = __serpent_decrypt }
131	} }
132};
133
134static int ecb_encrypt(struct skcipher_request *req)
135{
136	return glue_ecb_req_128bit(&serpent_enc, req);
137}
138
139static int ecb_decrypt(struct skcipher_request *req)
140{
141	return glue_ecb_req_128bit(&serpent_dec, req);
142}
143
144static int cbc_encrypt(struct skcipher_request *req)
145{
146	return glue_cbc_encrypt_req_128bit(__serpent_encrypt,
147					   req);
148}
149
150static int cbc_decrypt(struct skcipher_request *req)
151{
152	return glue_cbc_decrypt_req_128bit(&serpent_dec_cbc, req);
153}
154
155static int ctr_crypt(struct skcipher_request *req)
156{
157	return glue_ctr_req_128bit(&serpent_ctr, req);
158}
159
160static struct skcipher_alg serpent_algs[] = {
161	{
162		.base.cra_name		= "__ecb(serpent)",
163		.base.cra_driver_name	= "__ecb-serpent-sse2",
164		.base.cra_priority	= 400,
165		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
166		.base.cra_blocksize	= SERPENT_BLOCK_SIZE,
167		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
168		.base.cra_module	= THIS_MODULE,
169		.min_keysize		= SERPENT_MIN_KEY_SIZE,
170		.max_keysize		= SERPENT_MAX_KEY_SIZE,
171		.setkey			= serpent_setkey_skcipher,
172		.encrypt		= ecb_encrypt,
173		.decrypt		= ecb_decrypt,
174	}, {
175		.base.cra_name		= "__cbc(serpent)",
176		.base.cra_driver_name	= "__cbc-serpent-sse2",
177		.base.cra_priority	= 400,
178		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
179		.base.cra_blocksize	= SERPENT_BLOCK_SIZE,
180		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
181		.base.cra_module	= THIS_MODULE,
182		.min_keysize		= SERPENT_MIN_KEY_SIZE,
183		.max_keysize		= SERPENT_MAX_KEY_SIZE,
184		.ivsize			= SERPENT_BLOCK_SIZE,
185		.setkey			= serpent_setkey_skcipher,
186		.encrypt		= cbc_encrypt,
187		.decrypt		= cbc_decrypt,
188	}, {
189		.base.cra_name		= "__ctr(serpent)",
190		.base.cra_driver_name	= "__ctr-serpent-sse2",
191		.base.cra_priority	= 400,
192		.base.cra_flags		= CRYPTO_ALG_INTERNAL,
193		.base.cra_blocksize	= 1,
194		.base.cra_ctxsize	= sizeof(struct serpent_ctx),
195		.base.cra_module	= THIS_MODULE,
196		.min_keysize		= SERPENT_MIN_KEY_SIZE,
197		.max_keysize		= SERPENT_MAX_KEY_SIZE,
198		.ivsize			= SERPENT_BLOCK_SIZE,
199		.chunksize		= SERPENT_BLOCK_SIZE,
200		.setkey			= serpent_setkey_skcipher,
201		.encrypt		= ctr_crypt,
202		.decrypt		= ctr_crypt,
203	},
204};
205
206static struct simd_skcipher_alg *serpent_simd_algs[ARRAY_SIZE(serpent_algs)];
207
208static int __init serpent_sse2_init(void)
209{
210	if (!boot_cpu_has(X86_FEATURE_XMM2)) {
211		printk(KERN_INFO "SSE2 instructions are not detected.\n");
212		return -ENODEV;
213	}
214
215	return simd_register_skciphers_compat(serpent_algs,
216					      ARRAY_SIZE(serpent_algs),
217					      serpent_simd_algs);
218}
219
220static void __exit serpent_sse2_exit(void)
221{
222	simd_unregister_skciphers(serpent_algs, ARRAY_SIZE(serpent_algs),
223				  serpent_simd_algs);
224}
225
226module_init(serpent_sse2_init);
227module_exit(serpent_sse2_exit);
228
229MODULE_DESCRIPTION("Serpent Cipher Algorithm, SSE2 optimized");
230MODULE_LICENSE("GPL");
231MODULE_ALIAS_CRYPTO("serpent");
232