1 /*
2 * Shared glue code for 128bit block ciphers
3 *
4 * Copyright © 2012-2013 Jussi Kivilinna <jussi.kivilinna@iki.fi>
5 *
6 * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by:
7 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
8 * CTR part based on code (crypto/ctr.c) by:
9 * (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
24 * USA
25 *
26 */
27
28 #include <linux/module.h>
29 #include <crypto/b128ops.h>
30 #include <crypto/lrw.h>
31 #include <crypto/xts.h>
32 #include <asm/crypto/glue_helper.h>
33 #include <crypto/scatterwalk.h>
34
__glue_ecb_crypt_128bit(const struct common_glue_ctx * gctx,struct blkcipher_desc * desc,struct blkcipher_walk * walk)35 static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
36 struct blkcipher_desc *desc,
37 struct blkcipher_walk *walk)
38 {
39 void *ctx = crypto_blkcipher_ctx(desc->tfm);
40 const unsigned int bsize = 128 / 8;
41 unsigned int nbytes, i, func_bytes;
42 bool fpu_enabled = false;
43 int err;
44
45 err = blkcipher_walk_virt(desc, walk);
46
47 while ((nbytes = walk->nbytes)) {
48 u8 *wsrc = walk->src.virt.addr;
49 u8 *wdst = walk->dst.virt.addr;
50
51 fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
52 desc, fpu_enabled, nbytes);
53
54 for (i = 0; i < gctx->num_funcs; i++) {
55 func_bytes = bsize * gctx->funcs[i].num_blocks;
56
57 /* Process multi-block batch */
58 if (nbytes >= func_bytes) {
59 do {
60 gctx->funcs[i].fn_u.ecb(ctx, wdst,
61 wsrc);
62
63 wsrc += func_bytes;
64 wdst += func_bytes;
65 nbytes -= func_bytes;
66 } while (nbytes >= func_bytes);
67
68 if (nbytes < bsize)
69 goto done;
70 }
71 }
72
73 done:
74 err = blkcipher_walk_done(desc, walk, nbytes);
75 }
76
77 glue_fpu_end(fpu_enabled);
78 return err;
79 }
80
glue_ecb_crypt_128bit(const struct common_glue_ctx * gctx,struct blkcipher_desc * desc,struct scatterlist * dst,struct scatterlist * src,unsigned int nbytes)81 int glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
82 struct blkcipher_desc *desc, struct scatterlist *dst,
83 struct scatterlist *src, unsigned int nbytes)
84 {
85 struct blkcipher_walk walk;
86
87 blkcipher_walk_init(&walk, dst, src, nbytes);
88 return __glue_ecb_crypt_128bit(gctx, desc, &walk);
89 }
90 EXPORT_SYMBOL_GPL(glue_ecb_crypt_128bit);
91
__glue_cbc_encrypt_128bit(const common_glue_func_t fn,struct blkcipher_desc * desc,struct blkcipher_walk * walk)92 static unsigned int __glue_cbc_encrypt_128bit(const common_glue_func_t fn,
93 struct blkcipher_desc *desc,
94 struct blkcipher_walk *walk)
95 {
96 void *ctx = crypto_blkcipher_ctx(desc->tfm);
97 const unsigned int bsize = 128 / 8;
98 unsigned int nbytes = walk->nbytes;
99 u128 *src = (u128 *)walk->src.virt.addr;
100 u128 *dst = (u128 *)walk->dst.virt.addr;
101 u128 *iv = (u128 *)walk->iv;
102
103 do {
104 u128_xor(dst, src, iv);
105 fn(ctx, (u8 *)dst, (u8 *)dst);
106 iv = dst;
107
108 src += 1;
109 dst += 1;
110 nbytes -= bsize;
111 } while (nbytes >= bsize);
112
113 *(u128 *)walk->iv = *iv;
114 return nbytes;
115 }
116
glue_cbc_encrypt_128bit(const common_glue_func_t fn,struct blkcipher_desc * desc,struct scatterlist * dst,struct scatterlist * src,unsigned int nbytes)117 int glue_cbc_encrypt_128bit(const common_glue_func_t fn,
118 struct blkcipher_desc *desc,
119 struct scatterlist *dst,
120 struct scatterlist *src, unsigned int nbytes)
121 {
122 struct blkcipher_walk walk;
123 int err;
124
125 blkcipher_walk_init(&walk, dst, src, nbytes);
126 err = blkcipher_walk_virt(desc, &walk);
127
128 while ((nbytes = walk.nbytes)) {
129 nbytes = __glue_cbc_encrypt_128bit(fn, desc, &walk);
130 err = blkcipher_walk_done(desc, &walk, nbytes);
131 }
132
133 return err;
134 }
135 EXPORT_SYMBOL_GPL(glue_cbc_encrypt_128bit);
136
137 static unsigned int
__glue_cbc_decrypt_128bit(const struct common_glue_ctx * gctx,struct blkcipher_desc * desc,struct blkcipher_walk * walk)138 __glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx,
139 struct blkcipher_desc *desc,
140 struct blkcipher_walk *walk)
141 {
142 void *ctx = crypto_blkcipher_ctx(desc->tfm);
143 const unsigned int bsize = 128 / 8;
144 unsigned int nbytes = walk->nbytes;
145 u128 *src = (u128 *)walk->src.virt.addr;
146 u128 *dst = (u128 *)walk->dst.virt.addr;
147 u128 last_iv;
148 unsigned int num_blocks, func_bytes;
149 unsigned int i;
150
151 /* Start of the last block. */
152 src += nbytes / bsize - 1;
153 dst += nbytes / bsize - 1;
154
155 last_iv = *src;
156
157 for (i = 0; i < gctx->num_funcs; i++) {
158 num_blocks = gctx->funcs[i].num_blocks;
159 func_bytes = bsize * num_blocks;
160
161 /* Process multi-block batch */
162 if (nbytes >= func_bytes) {
163 do {
164 nbytes -= func_bytes - bsize;
165 src -= num_blocks - 1;
166 dst -= num_blocks - 1;
167
168 gctx->funcs[i].fn_u.cbc(ctx, dst, src);
169
170 nbytes -= bsize;
171 if (nbytes < bsize)
172 goto done;
173
174 u128_xor(dst, dst, src - 1);
175 src -= 1;
176 dst -= 1;
177 } while (nbytes >= func_bytes);
178
179 if (nbytes < bsize)
180 goto done;
181 }
182 }
183
184 done:
185 u128_xor(dst, dst, (u128 *)walk->iv);
186 *(u128 *)walk->iv = last_iv;
187
188 return nbytes;
189 }
190
glue_cbc_decrypt_128bit(const struct common_glue_ctx * gctx,struct blkcipher_desc * desc,struct scatterlist * dst,struct scatterlist * src,unsigned int nbytes)191 int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx,
192 struct blkcipher_desc *desc,
193 struct scatterlist *dst,
194 struct scatterlist *src, unsigned int nbytes)
195 {
196 const unsigned int bsize = 128 / 8;
197 bool fpu_enabled = false;
198 struct blkcipher_walk walk;
199 int err;
200
201 blkcipher_walk_init(&walk, dst, src, nbytes);
202 err = blkcipher_walk_virt(desc, &walk);
203
204 while ((nbytes = walk.nbytes)) {
205 fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
206 desc, fpu_enabled, nbytes);
207 nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk);
208 err = blkcipher_walk_done(desc, &walk, nbytes);
209 }
210
211 glue_fpu_end(fpu_enabled);
212 return err;
213 }
214 EXPORT_SYMBOL_GPL(glue_cbc_decrypt_128bit);
215
glue_ctr_crypt_final_128bit(const common_glue_ctr_func_t fn_ctr,struct blkcipher_desc * desc,struct blkcipher_walk * walk)216 static void glue_ctr_crypt_final_128bit(const common_glue_ctr_func_t fn_ctr,
217 struct blkcipher_desc *desc,
218 struct blkcipher_walk *walk)
219 {
220 void *ctx = crypto_blkcipher_ctx(desc->tfm);
221 u8 *src = (u8 *)walk->src.virt.addr;
222 u8 *dst = (u8 *)walk->dst.virt.addr;
223 unsigned int nbytes = walk->nbytes;
224 le128 ctrblk;
225 u128 tmp;
226
227 be128_to_le128(&ctrblk, (be128 *)walk->iv);
228
229 memcpy(&tmp, src, nbytes);
230 fn_ctr(ctx, &tmp, &tmp, &ctrblk);
231 memcpy(dst, &tmp, nbytes);
232
233 le128_to_be128((be128 *)walk->iv, &ctrblk);
234 }
235
__glue_ctr_crypt_128bit(const struct common_glue_ctx * gctx,struct blkcipher_desc * desc,struct blkcipher_walk * walk)236 static unsigned int __glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
237 struct blkcipher_desc *desc,
238 struct blkcipher_walk *walk)
239 {
240 const unsigned int bsize = 128 / 8;
241 void *ctx = crypto_blkcipher_ctx(desc->tfm);
242 unsigned int nbytes = walk->nbytes;
243 u128 *src = (u128 *)walk->src.virt.addr;
244 u128 *dst = (u128 *)walk->dst.virt.addr;
245 le128 ctrblk;
246 unsigned int num_blocks, func_bytes;
247 unsigned int i;
248
249 be128_to_le128(&ctrblk, (be128 *)walk->iv);
250
251 /* Process multi-block batch */
252 for (i = 0; i < gctx->num_funcs; i++) {
253 num_blocks = gctx->funcs[i].num_blocks;
254 func_bytes = bsize * num_blocks;
255
256 if (nbytes >= func_bytes) {
257 do {
258 gctx->funcs[i].fn_u.ctr(ctx, dst, src, &ctrblk);
259
260 src += num_blocks;
261 dst += num_blocks;
262 nbytes -= func_bytes;
263 } while (nbytes >= func_bytes);
264
265 if (nbytes < bsize)
266 goto done;
267 }
268 }
269
270 done:
271 le128_to_be128((be128 *)walk->iv, &ctrblk);
272 return nbytes;
273 }
274
glue_ctr_crypt_128bit(const struct common_glue_ctx * gctx,struct blkcipher_desc * desc,struct scatterlist * dst,struct scatterlist * src,unsigned int nbytes)275 int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
276 struct blkcipher_desc *desc, struct scatterlist *dst,
277 struct scatterlist *src, unsigned int nbytes)
278 {
279 const unsigned int bsize = 128 / 8;
280 bool fpu_enabled = false;
281 struct blkcipher_walk walk;
282 int err;
283
284 blkcipher_walk_init(&walk, dst, src, nbytes);
285 err = blkcipher_walk_virt_block(desc, &walk, bsize);
286
287 while ((nbytes = walk.nbytes) >= bsize) {
288 fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
289 desc, fpu_enabled, nbytes);
290 nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk);
291 err = blkcipher_walk_done(desc, &walk, nbytes);
292 }
293
294 glue_fpu_end(fpu_enabled);
295
296 if (walk.nbytes) {
297 glue_ctr_crypt_final_128bit(
298 gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk);
299 err = blkcipher_walk_done(desc, &walk, 0);
300 }
301
302 return err;
303 }
304 EXPORT_SYMBOL_GPL(glue_ctr_crypt_128bit);
305
__glue_xts_crypt_128bit(const struct common_glue_ctx * gctx,void * ctx,struct blkcipher_desc * desc,struct blkcipher_walk * walk)306 static unsigned int __glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
307 void *ctx,
308 struct blkcipher_desc *desc,
309 struct blkcipher_walk *walk)
310 {
311 const unsigned int bsize = 128 / 8;
312 unsigned int nbytes = walk->nbytes;
313 u128 *src = (u128 *)walk->src.virt.addr;
314 u128 *dst = (u128 *)walk->dst.virt.addr;
315 unsigned int num_blocks, func_bytes;
316 unsigned int i;
317
318 /* Process multi-block batch */
319 for (i = 0; i < gctx->num_funcs; i++) {
320 num_blocks = gctx->funcs[i].num_blocks;
321 func_bytes = bsize * num_blocks;
322
323 if (nbytes >= func_bytes) {
324 do {
325 gctx->funcs[i].fn_u.xts(ctx, dst, src,
326 (le128 *)walk->iv);
327
328 src += num_blocks;
329 dst += num_blocks;
330 nbytes -= func_bytes;
331 } while (nbytes >= func_bytes);
332
333 if (nbytes < bsize)
334 goto done;
335 }
336 }
337
338 done:
339 return nbytes;
340 }
341
342 /* for implementations implementing faster XTS IV generator */
glue_xts_crypt_128bit(const struct common_glue_ctx * gctx,struct blkcipher_desc * desc,struct scatterlist * dst,struct scatterlist * src,unsigned int nbytes,void (* tweak_fn)(void * ctx,u8 * dst,const u8 * src),void * tweak_ctx,void * crypt_ctx)343 int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
344 struct blkcipher_desc *desc, struct scatterlist *dst,
345 struct scatterlist *src, unsigned int nbytes,
346 void (*tweak_fn)(void *ctx, u8 *dst, const u8 *src),
347 void *tweak_ctx, void *crypt_ctx)
348 {
349 const unsigned int bsize = 128 / 8;
350 bool fpu_enabled = false;
351 struct blkcipher_walk walk;
352 int err;
353
354 blkcipher_walk_init(&walk, dst, src, nbytes);
355
356 err = blkcipher_walk_virt(desc, &walk);
357 nbytes = walk.nbytes;
358 if (!nbytes)
359 return err;
360
361 /* set minimum length to bsize, for tweak_fn */
362 fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit,
363 desc, fpu_enabled,
364 nbytes < bsize ? bsize : nbytes);
365
366 /* calculate first value of T */
367 tweak_fn(tweak_ctx, walk.iv, walk.iv);
368
369 while (nbytes) {
370 nbytes = __glue_xts_crypt_128bit(gctx, crypt_ctx, desc, &walk);
371
372 err = blkcipher_walk_done(desc, &walk, nbytes);
373 nbytes = walk.nbytes;
374 }
375
376 glue_fpu_end(fpu_enabled);
377
378 return err;
379 }
380 EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit);
381
glue_xts_crypt_128bit_one(void * ctx,u128 * dst,const u128 * src,le128 * iv,common_glue_func_t fn)382 void glue_xts_crypt_128bit_one(void *ctx, u128 *dst, const u128 *src, le128 *iv,
383 common_glue_func_t fn)
384 {
385 le128 ivblk = *iv;
386
387 /* generate next IV */
388 le128_gf128mul_x_ble(iv, &ivblk);
389
390 /* CC <- T xor C */
391 u128_xor(dst, src, (u128 *)&ivblk);
392
393 /* PP <- D(Key2,CC) */
394 fn(ctx, (u8 *)dst, (u8 *)dst);
395
396 /* P <- T xor PP */
397 u128_xor(dst, dst, (u128 *)&ivblk);
398 }
399 EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit_one);
400
401 MODULE_LICENSE("GPL");
402