1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Glue Code for 3-way parallel assembler optimized version of Twofish
4 *
5 * Copyright (c) 2011 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
6 */
7
8 #include <asm/crypto/glue_helper.h>
9 #include <asm/crypto/twofish.h>
10 #include <crypto/algapi.h>
11 #include <crypto/b128ops.h>
12 #include <crypto/internal/skcipher.h>
13 #include <crypto/twofish.h>
14 #include <linux/crypto.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/types.h>
18
19 EXPORT_SYMBOL_GPL(__twofish_enc_blk_3way);
20 EXPORT_SYMBOL_GPL(twofish_dec_blk_3way);
21
twofish_setkey_skcipher(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)22 static int twofish_setkey_skcipher(struct crypto_skcipher *tfm,
23 const u8 *key, unsigned int keylen)
24 {
25 return twofish_setkey(&tfm->base, key, keylen);
26 }
27
twofish_enc_blk_3way(const void * ctx,u8 * dst,const u8 * src)28 static inline void twofish_enc_blk_3way(const void *ctx, u8 *dst, const u8 *src)
29 {
30 __twofish_enc_blk_3way(ctx, dst, src, false);
31 }
32
twofish_enc_blk_xor_3way(const void * ctx,u8 * dst,const u8 * src)33 static inline void twofish_enc_blk_xor_3way(const void *ctx, u8 *dst,
34 const u8 *src)
35 {
36 __twofish_enc_blk_3way(ctx, dst, src, true);
37 }
38
twofish_dec_blk_cbc_3way(const void * ctx,u8 * d,const u8 * s)39 void twofish_dec_blk_cbc_3way(const void *ctx, u8 *d, const u8 *s)
40 {
41 u128 ivs[2];
42 u128 *dst = (u128 *)d;
43 const u128 *src = (const u128 *)s;
44
45 ivs[0] = src[0];
46 ivs[1] = src[1];
47
48 twofish_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src);
49
50 u128_xor(&dst[1], &dst[1], &ivs[0]);
51 u128_xor(&dst[2], &dst[2], &ivs[1]);
52 }
53 EXPORT_SYMBOL_GPL(twofish_dec_blk_cbc_3way);
54
twofish_enc_blk_ctr(const void * ctx,u8 * d,const u8 * s,le128 * iv)55 void twofish_enc_blk_ctr(const void *ctx, u8 *d, const u8 *s, le128 *iv)
56 {
57 be128 ctrblk;
58 u128 *dst = (u128 *)d;
59 const u128 *src = (const u128 *)s;
60
61 if (dst != src)
62 *dst = *src;
63
64 le128_to_be128(&ctrblk, iv);
65 le128_inc(iv);
66
67 twofish_enc_blk(ctx, (u8 *)&ctrblk, (u8 *)&ctrblk);
68 u128_xor(dst, dst, (u128 *)&ctrblk);
69 }
70 EXPORT_SYMBOL_GPL(twofish_enc_blk_ctr);
71
twofish_enc_blk_ctr_3way(const void * ctx,u8 * d,const u8 * s,le128 * iv)72 void twofish_enc_blk_ctr_3way(const void *ctx, u8 *d, const u8 *s, le128 *iv)
73 {
74 be128 ctrblks[3];
75 u128 *dst = (u128 *)d;
76 const u128 *src = (const u128 *)s;
77
78 if (dst != src) {
79 dst[0] = src[0];
80 dst[1] = src[1];
81 dst[2] = src[2];
82 }
83
84 le128_to_be128(&ctrblks[0], iv);
85 le128_inc(iv);
86 le128_to_be128(&ctrblks[1], iv);
87 le128_inc(iv);
88 le128_to_be128(&ctrblks[2], iv);
89 le128_inc(iv);
90
91 twofish_enc_blk_xor_3way(ctx, (u8 *)dst, (u8 *)ctrblks);
92 }
93 EXPORT_SYMBOL_GPL(twofish_enc_blk_ctr_3way);
94
95 static const struct common_glue_ctx twofish_enc = {
96 .num_funcs = 2,
97 .fpu_blocks_limit = -1,
98
99 .funcs = { {
100 .num_blocks = 3,
101 .fn_u = { .ecb = twofish_enc_blk_3way }
102 }, {
103 .num_blocks = 1,
104 .fn_u = { .ecb = twofish_enc_blk }
105 } }
106 };
107
108 static const struct common_glue_ctx twofish_ctr = {
109 .num_funcs = 2,
110 .fpu_blocks_limit = -1,
111
112 .funcs = { {
113 .num_blocks = 3,
114 .fn_u = { .ctr = twofish_enc_blk_ctr_3way }
115 }, {
116 .num_blocks = 1,
117 .fn_u = { .ctr = twofish_enc_blk_ctr }
118 } }
119 };
120
121 static const struct common_glue_ctx twofish_dec = {
122 .num_funcs = 2,
123 .fpu_blocks_limit = -1,
124
125 .funcs = { {
126 .num_blocks = 3,
127 .fn_u = { .ecb = twofish_dec_blk_3way }
128 }, {
129 .num_blocks = 1,
130 .fn_u = { .ecb = twofish_dec_blk }
131 } }
132 };
133
134 static const struct common_glue_ctx twofish_dec_cbc = {
135 .num_funcs = 2,
136 .fpu_blocks_limit = -1,
137
138 .funcs = { {
139 .num_blocks = 3,
140 .fn_u = { .cbc = twofish_dec_blk_cbc_3way }
141 }, {
142 .num_blocks = 1,
143 .fn_u = { .cbc = twofish_dec_blk }
144 } }
145 };
146
ecb_encrypt(struct skcipher_request * req)147 static int ecb_encrypt(struct skcipher_request *req)
148 {
149 return glue_ecb_req_128bit(&twofish_enc, req);
150 }
151
ecb_decrypt(struct skcipher_request * req)152 static int ecb_decrypt(struct skcipher_request *req)
153 {
154 return glue_ecb_req_128bit(&twofish_dec, req);
155 }
156
cbc_encrypt(struct skcipher_request * req)157 static int cbc_encrypt(struct skcipher_request *req)
158 {
159 return glue_cbc_encrypt_req_128bit(twofish_enc_blk, req);
160 }
161
cbc_decrypt(struct skcipher_request * req)162 static int cbc_decrypt(struct skcipher_request *req)
163 {
164 return glue_cbc_decrypt_req_128bit(&twofish_dec_cbc, req);
165 }
166
ctr_crypt(struct skcipher_request * req)167 static int ctr_crypt(struct skcipher_request *req)
168 {
169 return glue_ctr_req_128bit(&twofish_ctr, req);
170 }
171
172 static struct skcipher_alg tf_skciphers[] = {
173 {
174 .base.cra_name = "ecb(twofish)",
175 .base.cra_driver_name = "ecb-twofish-3way",
176 .base.cra_priority = 300,
177 .base.cra_blocksize = TF_BLOCK_SIZE,
178 .base.cra_ctxsize = sizeof(struct twofish_ctx),
179 .base.cra_module = THIS_MODULE,
180 .min_keysize = TF_MIN_KEY_SIZE,
181 .max_keysize = TF_MAX_KEY_SIZE,
182 .setkey = twofish_setkey_skcipher,
183 .encrypt = ecb_encrypt,
184 .decrypt = ecb_decrypt,
185 }, {
186 .base.cra_name = "cbc(twofish)",
187 .base.cra_driver_name = "cbc-twofish-3way",
188 .base.cra_priority = 300,
189 .base.cra_blocksize = TF_BLOCK_SIZE,
190 .base.cra_ctxsize = sizeof(struct twofish_ctx),
191 .base.cra_module = THIS_MODULE,
192 .min_keysize = TF_MIN_KEY_SIZE,
193 .max_keysize = TF_MAX_KEY_SIZE,
194 .ivsize = TF_BLOCK_SIZE,
195 .setkey = twofish_setkey_skcipher,
196 .encrypt = cbc_encrypt,
197 .decrypt = cbc_decrypt,
198 }, {
199 .base.cra_name = "ctr(twofish)",
200 .base.cra_driver_name = "ctr-twofish-3way",
201 .base.cra_priority = 300,
202 .base.cra_blocksize = 1,
203 .base.cra_ctxsize = sizeof(struct twofish_ctx),
204 .base.cra_module = THIS_MODULE,
205 .min_keysize = TF_MIN_KEY_SIZE,
206 .max_keysize = TF_MAX_KEY_SIZE,
207 .ivsize = TF_BLOCK_SIZE,
208 .chunksize = TF_BLOCK_SIZE,
209 .setkey = twofish_setkey_skcipher,
210 .encrypt = ctr_crypt,
211 .decrypt = ctr_crypt,
212 },
213 };
214
is_blacklisted_cpu(void)215 static bool is_blacklisted_cpu(void)
216 {
217 if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
218 return false;
219
220 if (boot_cpu_data.x86 == 0x06 &&
221 (boot_cpu_data.x86_model == 0x1c ||
222 boot_cpu_data.x86_model == 0x26 ||
223 boot_cpu_data.x86_model == 0x36)) {
224 /*
225 * On Atom, twofish-3way is slower than original assembler
226 * implementation. Twofish-3way trades off some performance in
227 * storing blocks in 64bit registers to allow three blocks to
228 * be processed parallel. Parallel operation then allows gaining
229 * more performance than was trade off, on out-of-order CPUs.
230 * However Atom does not benefit from this parallellism and
231 * should be blacklisted.
232 */
233 return true;
234 }
235
236 if (boot_cpu_data.x86 == 0x0f) {
237 /*
238 * On Pentium 4, twofish-3way is slower than original assembler
239 * implementation because excessive uses of 64bit rotate and
240 * left-shifts (which are really slow on P4) needed to store and
241 * handle 128bit block in two 64bit registers.
242 */
243 return true;
244 }
245
246 return false;
247 }
248
249 static int force;
250 module_param(force, int, 0);
251 MODULE_PARM_DESC(force, "Force module load, ignore CPU blacklist");
252
init(void)253 static int __init init(void)
254 {
255 if (!force && is_blacklisted_cpu()) {
256 printk(KERN_INFO
257 "twofish-x86_64-3way: performance on this CPU "
258 "would be suboptimal: disabling "
259 "twofish-x86_64-3way.\n");
260 return -ENODEV;
261 }
262
263 return crypto_register_skciphers(tf_skciphers,
264 ARRAY_SIZE(tf_skciphers));
265 }
266
fini(void)267 static void __exit fini(void)
268 {
269 crypto_unregister_skciphers(tf_skciphers, ARRAY_SIZE(tf_skciphers));
270 }
271
272 module_init(init);
273 module_exit(fini);
274
275 MODULE_LICENSE("GPL");
276 MODULE_DESCRIPTION("Twofish Cipher Algorithm, 3-way parallel asm optimized");
277 MODULE_ALIAS_CRYPTO("twofish");
278 MODULE_ALIAS_CRYPTO("twofish-asm");
279