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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Glue code for AES implementation for SPE instructions (PPC)
4 *
5 * Based on generic implementation. The assembler module takes care
6 * about the SPE registers so it can run from interrupt context.
7 *
8 * Copyright (c) 2015 Markus Stockhausen <stockhausen@collogia.de>
9 */
10
11#include <crypto/aes.h>
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/types.h>
15#include <linux/errno.h>
16#include <linux/crypto.h>
17#include <asm/byteorder.h>
18#include <asm/switch_to.h>
19#include <crypto/algapi.h>
20#include <crypto/internal/skcipher.h>
21#include <crypto/xts.h>
22#include <crypto/gf128mul.h>
23#include <crypto/scatterwalk.h>
24
25/*
26 * MAX_BYTES defines the number of bytes that are allowed to be processed
27 * between preempt_disable() and preempt_enable(). e500 cores can issue two
28 * instructions per clock cycle using one 32/64 bit unit (SU1) and one 32
29 * bit unit (SU2). One of these can be a memory access that is executed via
30 * a single load and store unit (LSU). XTS-AES-256 takes ~780 operations per
31 * 16 byte block or 25 cycles per byte. Thus 768 bytes of input data
32 * will need an estimated maximum of 20,000 cycles. Headroom for cache misses
33 * included. Even with the low end model clocked at 667 MHz this equals to a
34 * critical time window of less than 30us. The value has been chosen to
35 * process a 512 byte disk block in one or a large 1400 bytes IPsec network
36 * packet in two runs.
37 *
38 */
39#define MAX_BYTES 768
40
41struct ppc_aes_ctx {
42 u32 key_enc[AES_MAX_KEYLENGTH_U32];
43 u32 key_dec[AES_MAX_KEYLENGTH_U32];
44 u32 rounds;
45};
46
47struct ppc_xts_ctx {
48 u32 key_enc[AES_MAX_KEYLENGTH_U32];
49 u32 key_dec[AES_MAX_KEYLENGTH_U32];
50 u32 key_twk[AES_MAX_KEYLENGTH_U32];
51 u32 rounds;
52};
53
54extern void ppc_encrypt_aes(u8 *out, const u8 *in, u32 *key_enc, u32 rounds);
55extern void ppc_decrypt_aes(u8 *out, const u8 *in, u32 *key_dec, u32 rounds);
56extern void ppc_encrypt_ecb(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
57 u32 bytes);
58extern void ppc_decrypt_ecb(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
59 u32 bytes);
60extern void ppc_encrypt_cbc(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
61 u32 bytes, u8 *iv);
62extern void ppc_decrypt_cbc(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
63 u32 bytes, u8 *iv);
64extern void ppc_crypt_ctr (u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
65 u32 bytes, u8 *iv);
66extern void ppc_encrypt_xts(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
67 u32 bytes, u8 *iv, u32 *key_twk);
68extern void ppc_decrypt_xts(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
69 u32 bytes, u8 *iv, u32 *key_twk);
70
71extern void ppc_expand_key_128(u32 *key_enc, const u8 *key);
72extern void ppc_expand_key_192(u32 *key_enc, const u8 *key);
73extern void ppc_expand_key_256(u32 *key_enc, const u8 *key);
74
75extern void ppc_generate_decrypt_key(u32 *key_dec,u32 *key_enc,
76 unsigned int key_len);
77
78static void spe_begin(void)
79{
80 /* disable preemption and save users SPE registers if required */
81 preempt_disable();
82 enable_kernel_spe();
83}
84
85static void spe_end(void)
86{
87 disable_kernel_spe();
88 /* reenable preemption */
89 preempt_enable();
90}
91
92static int ppc_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
93 unsigned int key_len)
94{
95 struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
96
97 switch (key_len) {
98 case AES_KEYSIZE_128:
99 ctx->rounds = 4;
100 ppc_expand_key_128(ctx->key_enc, in_key);
101 break;
102 case AES_KEYSIZE_192:
103 ctx->rounds = 5;
104 ppc_expand_key_192(ctx->key_enc, in_key);
105 break;
106 case AES_KEYSIZE_256:
107 ctx->rounds = 6;
108 ppc_expand_key_256(ctx->key_enc, in_key);
109 break;
110 default:
111 return -EINVAL;
112 }
113
114 ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);
115
116 return 0;
117}
118
119static int ppc_aes_setkey_skcipher(struct crypto_skcipher *tfm,
120 const u8 *in_key, unsigned int key_len)
121{
122 return ppc_aes_setkey(crypto_skcipher_tfm(tfm), in_key, key_len);
123}
124
125static int ppc_xts_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
126 unsigned int key_len)
127{
128 struct ppc_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
129 int err;
130
131 err = xts_verify_key(tfm, in_key, key_len);
132 if (err)
133 return err;
134
135 key_len >>= 1;
136
137 switch (key_len) {
138 case AES_KEYSIZE_128:
139 ctx->rounds = 4;
140 ppc_expand_key_128(ctx->key_enc, in_key);
141 ppc_expand_key_128(ctx->key_twk, in_key + AES_KEYSIZE_128);
142 break;
143 case AES_KEYSIZE_192:
144 ctx->rounds = 5;
145 ppc_expand_key_192(ctx->key_enc, in_key);
146 ppc_expand_key_192(ctx->key_twk, in_key + AES_KEYSIZE_192);
147 break;
148 case AES_KEYSIZE_256:
149 ctx->rounds = 6;
150 ppc_expand_key_256(ctx->key_enc, in_key);
151 ppc_expand_key_256(ctx->key_twk, in_key + AES_KEYSIZE_256);
152 break;
153 default:
154 return -EINVAL;
155 }
156
157 ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);
158
159 return 0;
160}
161
162static void ppc_aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
163{
164 struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
165
166 spe_begin();
167 ppc_encrypt_aes(out, in, ctx->key_enc, ctx->rounds);
168 spe_end();
169}
170
171static void ppc_aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
172{
173 struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
174
175 spe_begin();
176 ppc_decrypt_aes(out, in, ctx->key_dec, ctx->rounds);
177 spe_end();
178}
179
180static int ppc_ecb_crypt(struct skcipher_request *req, bool enc)
181{
182 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
183 struct ppc_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
184 struct skcipher_walk walk;
185 unsigned int nbytes;
186 int err;
187
188 err = skcipher_walk_virt(&walk, req, false);
189
190 while ((nbytes = walk.nbytes) != 0) {
191 nbytes = min_t(unsigned int, nbytes, MAX_BYTES);
192 nbytes = round_down(nbytes, AES_BLOCK_SIZE);
193
194 spe_begin();
195 if (enc)
196 ppc_encrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
197 ctx->key_enc, ctx->rounds, nbytes);
198 else
199 ppc_decrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
200 ctx->key_dec, ctx->rounds, nbytes);
201 spe_end();
202
203 err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
204 }
205
206 return err;
207}
208
209static int ppc_ecb_encrypt(struct skcipher_request *req)
210{
211 return ppc_ecb_crypt(req, true);
212}
213
214static int ppc_ecb_decrypt(struct skcipher_request *req)
215{
216 return ppc_ecb_crypt(req, false);
217}
218
219static int ppc_cbc_crypt(struct skcipher_request *req, bool enc)
220{
221 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
222 struct ppc_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
223 struct skcipher_walk walk;
224 unsigned int nbytes;
225 int err;
226
227 err = skcipher_walk_virt(&walk, req, false);
228
229 while ((nbytes = walk.nbytes) != 0) {
230 nbytes = min_t(unsigned int, nbytes, MAX_BYTES);
231 nbytes = round_down(nbytes, AES_BLOCK_SIZE);
232
233 spe_begin();
234 if (enc)
235 ppc_encrypt_cbc(walk.dst.virt.addr, walk.src.virt.addr,
236 ctx->key_enc, ctx->rounds, nbytes,
237 walk.iv);
238 else
239 ppc_decrypt_cbc(walk.dst.virt.addr, walk.src.virt.addr,
240 ctx->key_dec, ctx->rounds, nbytes,
241 walk.iv);
242 spe_end();
243
244 err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
245 }
246
247 return err;
248}
249
250static int ppc_cbc_encrypt(struct skcipher_request *req)
251{
252 return ppc_cbc_crypt(req, true);
253}
254
255static int ppc_cbc_decrypt(struct skcipher_request *req)
256{
257 return ppc_cbc_crypt(req, false);
258}
259
260static int ppc_ctr_crypt(struct skcipher_request *req)
261{
262 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
263 struct ppc_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
264 struct skcipher_walk walk;
265 unsigned int nbytes;
266 int err;
267
268 err = skcipher_walk_virt(&walk, req, false);
269
270 while ((nbytes = walk.nbytes) != 0) {
271 nbytes = min_t(unsigned int, nbytes, MAX_BYTES);
272 if (nbytes < walk.total)
273 nbytes = round_down(nbytes, AES_BLOCK_SIZE);
274
275 spe_begin();
276 ppc_crypt_ctr(walk.dst.virt.addr, walk.src.virt.addr,
277 ctx->key_enc, ctx->rounds, nbytes, walk.iv);
278 spe_end();
279
280 err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
281 }
282
283 return err;
284}
285
286static int ppc_xts_crypt(struct skcipher_request *req, bool enc)
287{
288 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
289 struct ppc_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
290 struct skcipher_walk walk;
291 unsigned int nbytes;
292 int err;
293 u32 *twk;
294
295 err = skcipher_walk_virt(&walk, req, false);
296 twk = ctx->key_twk;
297
298 while ((nbytes = walk.nbytes) != 0) {
299 nbytes = min_t(unsigned int, nbytes, MAX_BYTES);
300 nbytes = round_down(nbytes, AES_BLOCK_SIZE);
301
302 spe_begin();
303 if (enc)
304 ppc_encrypt_xts(walk.dst.virt.addr, walk.src.virt.addr,
305 ctx->key_enc, ctx->rounds, nbytes,
306 walk.iv, twk);
307 else
308 ppc_decrypt_xts(walk.dst.virt.addr, walk.src.virt.addr,
309 ctx->key_dec, ctx->rounds, nbytes,
310 walk.iv, twk);
311 spe_end();
312
313 twk = NULL;
314 err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
315 }
316
317 return err;
318}
319
320static int ppc_xts_encrypt(struct skcipher_request *req)
321{
322 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
323 struct ppc_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
324 int tail = req->cryptlen % AES_BLOCK_SIZE;
325 int offset = req->cryptlen - tail - AES_BLOCK_SIZE;
326 struct skcipher_request subreq;
327 u8 b[2][AES_BLOCK_SIZE];
328 int err;
329
330 if (req->cryptlen < AES_BLOCK_SIZE)
331 return -EINVAL;
332
333 if (tail) {
334 subreq = *req;
335 skcipher_request_set_crypt(&subreq, req->src, req->dst,
336 req->cryptlen - tail, req->iv);
337 req = &subreq;
338 }
339
340 err = ppc_xts_crypt(req, true);
341 if (err || !tail)
342 return err;
343
344 scatterwalk_map_and_copy(b[0], req->dst, offset, AES_BLOCK_SIZE, 0);
345 memcpy(b[1], b[0], tail);
346 scatterwalk_map_and_copy(b[0], req->src, offset + AES_BLOCK_SIZE, tail, 0);
347
348 spe_begin();
349 ppc_encrypt_xts(b[0], b[0], ctx->key_enc, ctx->rounds, AES_BLOCK_SIZE,
350 req->iv, NULL);
351 spe_end();
352
353 scatterwalk_map_and_copy(b[0], req->dst, offset, AES_BLOCK_SIZE + tail, 1);
354
355 return 0;
356}
357
358static int ppc_xts_decrypt(struct skcipher_request *req)
359{
360 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
361 struct ppc_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
362 int tail = req->cryptlen % AES_BLOCK_SIZE;
363 int offset = req->cryptlen - tail - AES_BLOCK_SIZE;
364 struct skcipher_request subreq;
365 u8 b[3][AES_BLOCK_SIZE];
366 le128 twk;
367 int err;
368
369 if (req->cryptlen < AES_BLOCK_SIZE)
370 return -EINVAL;
371
372 if (tail) {
373 subreq = *req;
374 skcipher_request_set_crypt(&subreq, req->src, req->dst,
375 offset, req->iv);
376 req = &subreq;
377 }
378
379 err = ppc_xts_crypt(req, false);
380 if (err || !tail)
381 return err;
382
383 scatterwalk_map_and_copy(b[1], req->src, offset, AES_BLOCK_SIZE + tail, 0);
384
385 spe_begin();
386 if (!offset)
387 ppc_encrypt_ecb(req->iv, req->iv, ctx->key_twk, ctx->rounds,
388 AES_BLOCK_SIZE);
389
390 gf128mul_x_ble(&twk, (le128 *)req->iv);
391
392 ppc_decrypt_xts(b[1], b[1], ctx->key_dec, ctx->rounds, AES_BLOCK_SIZE,
393 (u8 *)&twk, NULL);
394 memcpy(b[0], b[2], tail);
395 memcpy(b[0] + tail, b[1] + tail, AES_BLOCK_SIZE - tail);
396 ppc_decrypt_xts(b[0], b[0], ctx->key_dec, ctx->rounds, AES_BLOCK_SIZE,
397 req->iv, NULL);
398 spe_end();
399
400 scatterwalk_map_and_copy(b[0], req->dst, offset, AES_BLOCK_SIZE + tail, 1);
401
402 return 0;
403}
404
405/*
406 * Algorithm definitions. Disabling alignment (cra_alignmask=0) was chosen
407 * because the e500 platform can handle unaligned reads/writes very efficiently.
408 * This improves IPsec thoughput by another few percent. Additionally we assume
409 * that AES context is always aligned to at least 8 bytes because it is created
410 * with kmalloc() in the crypto infrastructure
411 */
412
413static struct crypto_alg aes_cipher_alg = {
414 .cra_name = "aes",
415 .cra_driver_name = "aes-ppc-spe",
416 .cra_priority = 300,
417 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
418 .cra_blocksize = AES_BLOCK_SIZE,
419 .cra_ctxsize = sizeof(struct ppc_aes_ctx),
420 .cra_alignmask = 0,
421 .cra_module = THIS_MODULE,
422 .cra_u = {
423 .cipher = {
424 .cia_min_keysize = AES_MIN_KEY_SIZE,
425 .cia_max_keysize = AES_MAX_KEY_SIZE,
426 .cia_setkey = ppc_aes_setkey,
427 .cia_encrypt = ppc_aes_encrypt,
428 .cia_decrypt = ppc_aes_decrypt
429 }
430 }
431};
432
433static struct skcipher_alg aes_skcipher_algs[] = {
434 {
435 .base.cra_name = "ecb(aes)",
436 .base.cra_driver_name = "ecb-ppc-spe",
437 .base.cra_priority = 300,
438 .base.cra_blocksize = AES_BLOCK_SIZE,
439 .base.cra_ctxsize = sizeof(struct ppc_aes_ctx),
440 .base.cra_module = THIS_MODULE,
441 .min_keysize = AES_MIN_KEY_SIZE,
442 .max_keysize = AES_MAX_KEY_SIZE,
443 .setkey = ppc_aes_setkey_skcipher,
444 .encrypt = ppc_ecb_encrypt,
445 .decrypt = ppc_ecb_decrypt,
446 }, {
447 .base.cra_name = "cbc(aes)",
448 .base.cra_driver_name = "cbc-ppc-spe",
449 .base.cra_priority = 300,
450 .base.cra_blocksize = AES_BLOCK_SIZE,
451 .base.cra_ctxsize = sizeof(struct ppc_aes_ctx),
452 .base.cra_module = THIS_MODULE,
453 .min_keysize = AES_MIN_KEY_SIZE,
454 .max_keysize = AES_MAX_KEY_SIZE,
455 .ivsize = AES_BLOCK_SIZE,
456 .setkey = ppc_aes_setkey_skcipher,
457 .encrypt = ppc_cbc_encrypt,
458 .decrypt = ppc_cbc_decrypt,
459 }, {
460 .base.cra_name = "ctr(aes)",
461 .base.cra_driver_name = "ctr-ppc-spe",
462 .base.cra_priority = 300,
463 .base.cra_blocksize = 1,
464 .base.cra_ctxsize = sizeof(struct ppc_aes_ctx),
465 .base.cra_module = THIS_MODULE,
466 .min_keysize = AES_MIN_KEY_SIZE,
467 .max_keysize = AES_MAX_KEY_SIZE,
468 .ivsize = AES_BLOCK_SIZE,
469 .setkey = ppc_aes_setkey_skcipher,
470 .encrypt = ppc_ctr_crypt,
471 .decrypt = ppc_ctr_crypt,
472 .chunksize = AES_BLOCK_SIZE,
473 }, {
474 .base.cra_name = "xts(aes)",
475 .base.cra_driver_name = "xts-ppc-spe",
476 .base.cra_priority = 300,
477 .base.cra_blocksize = AES_BLOCK_SIZE,
478 .base.cra_ctxsize = sizeof(struct ppc_xts_ctx),
479 .base.cra_module = THIS_MODULE,
480 .min_keysize = AES_MIN_KEY_SIZE * 2,
481 .max_keysize = AES_MAX_KEY_SIZE * 2,
482 .ivsize = AES_BLOCK_SIZE,
483 .setkey = ppc_xts_setkey,
484 .encrypt = ppc_xts_encrypt,
485 .decrypt = ppc_xts_decrypt,
486 }
487};
488
489static int __init ppc_aes_mod_init(void)
490{
491 int err;
492
493 err = crypto_register_alg(&aes_cipher_alg);
494 if (err)
495 return err;
496
497 err = crypto_register_skciphers(aes_skcipher_algs,
498 ARRAY_SIZE(aes_skcipher_algs));
499 if (err)
500 crypto_unregister_alg(&aes_cipher_alg);
501 return err;
502}
503
504static void __exit ppc_aes_mod_fini(void)
505{
506 crypto_unregister_alg(&aes_cipher_alg);
507 crypto_unregister_skciphers(aes_skcipher_algs,
508 ARRAY_SIZE(aes_skcipher_algs));
509}
510
511module_init(ppc_aes_mod_init);
512module_exit(ppc_aes_mod_fini);
513
514MODULE_LICENSE("GPL");
515MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS, SPE optimized");
516
517MODULE_ALIAS_CRYPTO("aes");
518MODULE_ALIAS_CRYPTO("ecb(aes)");
519MODULE_ALIAS_CRYPTO("cbc(aes)");
520MODULE_ALIAS_CRYPTO("ctr(aes)");
521MODULE_ALIAS_CRYPTO("xts(aes)");
522MODULE_ALIAS_CRYPTO("aes-ppc-spe");
1/*
2 * Glue code for AES implementation for SPE instructions (PPC)
3 *
4 * Based on generic implementation. The assembler module takes care
5 * about the SPE registers so it can run from interrupt context.
6 *
7 * Copyright (c) 2015 Markus Stockhausen <stockhausen@collogia.de>
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the Free
11 * Software Foundation; either version 2 of the License, or (at your option)
12 * any later version.
13 *
14 */
15
16#include <crypto/aes.h>
17#include <linux/module.h>
18#include <linux/init.h>
19#include <linux/types.h>
20#include <linux/errno.h>
21#include <linux/crypto.h>
22#include <asm/byteorder.h>
23#include <asm/switch_to.h>
24#include <crypto/algapi.h>
25#include <crypto/xts.h>
26
27/*
28 * MAX_BYTES defines the number of bytes that are allowed to be processed
29 * between preempt_disable() and preempt_enable(). e500 cores can issue two
30 * instructions per clock cycle using one 32/64 bit unit (SU1) and one 32
31 * bit unit (SU2). One of these can be a memory access that is executed via
32 * a single load and store unit (LSU). XTS-AES-256 takes ~780 operations per
33 * 16 byte block block or 25 cycles per byte. Thus 768 bytes of input data
34 * will need an estimated maximum of 20,000 cycles. Headroom for cache misses
35 * included. Even with the low end model clocked at 667 MHz this equals to a
36 * critical time window of less than 30us. The value has been chosen to
37 * process a 512 byte disk block in one or a large 1400 bytes IPsec network
38 * packet in two runs.
39 *
40 */
41#define MAX_BYTES 768
42
43struct ppc_aes_ctx {
44 u32 key_enc[AES_MAX_KEYLENGTH_U32];
45 u32 key_dec[AES_MAX_KEYLENGTH_U32];
46 u32 rounds;
47};
48
49struct ppc_xts_ctx {
50 u32 key_enc[AES_MAX_KEYLENGTH_U32];
51 u32 key_dec[AES_MAX_KEYLENGTH_U32];
52 u32 key_twk[AES_MAX_KEYLENGTH_U32];
53 u32 rounds;
54};
55
56extern void ppc_encrypt_aes(u8 *out, const u8 *in, u32 *key_enc, u32 rounds);
57extern void ppc_decrypt_aes(u8 *out, const u8 *in, u32 *key_dec, u32 rounds);
58extern void ppc_encrypt_ecb(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
59 u32 bytes);
60extern void ppc_decrypt_ecb(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
61 u32 bytes);
62extern void ppc_encrypt_cbc(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
63 u32 bytes, u8 *iv);
64extern void ppc_decrypt_cbc(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
65 u32 bytes, u8 *iv);
66extern void ppc_crypt_ctr (u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
67 u32 bytes, u8 *iv);
68extern void ppc_encrypt_xts(u8 *out, const u8 *in, u32 *key_enc, u32 rounds,
69 u32 bytes, u8 *iv, u32 *key_twk);
70extern void ppc_decrypt_xts(u8 *out, const u8 *in, u32 *key_dec, u32 rounds,
71 u32 bytes, u8 *iv, u32 *key_twk);
72
73extern void ppc_expand_key_128(u32 *key_enc, const u8 *key);
74extern void ppc_expand_key_192(u32 *key_enc, const u8 *key);
75extern void ppc_expand_key_256(u32 *key_enc, const u8 *key);
76
77extern void ppc_generate_decrypt_key(u32 *key_dec,u32 *key_enc,
78 unsigned int key_len);
79
80static void spe_begin(void)
81{
82 /* disable preemption and save users SPE registers if required */
83 preempt_disable();
84 enable_kernel_spe();
85}
86
87static void spe_end(void)
88{
89 disable_kernel_spe();
90 /* reenable preemption */
91 preempt_enable();
92}
93
94static int ppc_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
95 unsigned int key_len)
96{
97 struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
98
99 if (key_len != AES_KEYSIZE_128 &&
100 key_len != AES_KEYSIZE_192 &&
101 key_len != AES_KEYSIZE_256) {
102 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
103 return -EINVAL;
104 }
105
106 switch (key_len) {
107 case AES_KEYSIZE_128:
108 ctx->rounds = 4;
109 ppc_expand_key_128(ctx->key_enc, in_key);
110 break;
111 case AES_KEYSIZE_192:
112 ctx->rounds = 5;
113 ppc_expand_key_192(ctx->key_enc, in_key);
114 break;
115 case AES_KEYSIZE_256:
116 ctx->rounds = 6;
117 ppc_expand_key_256(ctx->key_enc, in_key);
118 break;
119 }
120
121 ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);
122
123 return 0;
124}
125
126static int ppc_xts_setkey(struct crypto_tfm *tfm, const u8 *in_key,
127 unsigned int key_len)
128{
129 struct ppc_xts_ctx *ctx = crypto_tfm_ctx(tfm);
130 int err;
131
132 err = xts_check_key(tfm, in_key, key_len);
133 if (err)
134 return err;
135
136 key_len >>= 1;
137
138 if (key_len != AES_KEYSIZE_128 &&
139 key_len != AES_KEYSIZE_192 &&
140 key_len != AES_KEYSIZE_256) {
141 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
142 return -EINVAL;
143 }
144
145 switch (key_len) {
146 case AES_KEYSIZE_128:
147 ctx->rounds = 4;
148 ppc_expand_key_128(ctx->key_enc, in_key);
149 ppc_expand_key_128(ctx->key_twk, in_key + AES_KEYSIZE_128);
150 break;
151 case AES_KEYSIZE_192:
152 ctx->rounds = 5;
153 ppc_expand_key_192(ctx->key_enc, in_key);
154 ppc_expand_key_192(ctx->key_twk, in_key + AES_KEYSIZE_192);
155 break;
156 case AES_KEYSIZE_256:
157 ctx->rounds = 6;
158 ppc_expand_key_256(ctx->key_enc, in_key);
159 ppc_expand_key_256(ctx->key_twk, in_key + AES_KEYSIZE_256);
160 break;
161 }
162
163 ppc_generate_decrypt_key(ctx->key_dec, ctx->key_enc, key_len);
164
165 return 0;
166}
167
168static void ppc_aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
169{
170 struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
171
172 spe_begin();
173 ppc_encrypt_aes(out, in, ctx->key_enc, ctx->rounds);
174 spe_end();
175}
176
177static void ppc_aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
178{
179 struct ppc_aes_ctx *ctx = crypto_tfm_ctx(tfm);
180
181 spe_begin();
182 ppc_decrypt_aes(out, in, ctx->key_dec, ctx->rounds);
183 spe_end();
184}
185
186static int ppc_ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
187 struct scatterlist *src, unsigned int nbytes)
188{
189 struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
190 struct blkcipher_walk walk;
191 unsigned int ubytes;
192 int err;
193
194 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
195 blkcipher_walk_init(&walk, dst, src, nbytes);
196 err = blkcipher_walk_virt(desc, &walk);
197
198 while ((nbytes = walk.nbytes)) {
199 ubytes = nbytes > MAX_BYTES ?
200 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
201 nbytes -= ubytes;
202
203 spe_begin();
204 ppc_encrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
205 ctx->key_enc, ctx->rounds, nbytes);
206 spe_end();
207
208 err = blkcipher_walk_done(desc, &walk, ubytes);
209 }
210
211 return err;
212}
213
214static int ppc_ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
215 struct scatterlist *src, unsigned int nbytes)
216{
217 struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
218 struct blkcipher_walk walk;
219 unsigned int ubytes;
220 int err;
221
222 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
223 blkcipher_walk_init(&walk, dst, src, nbytes);
224 err = blkcipher_walk_virt(desc, &walk);
225
226 while ((nbytes = walk.nbytes)) {
227 ubytes = nbytes > MAX_BYTES ?
228 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
229 nbytes -= ubytes;
230
231 spe_begin();
232 ppc_decrypt_ecb(walk.dst.virt.addr, walk.src.virt.addr,
233 ctx->key_dec, ctx->rounds, nbytes);
234 spe_end();
235
236 err = blkcipher_walk_done(desc, &walk, ubytes);
237 }
238
239 return err;
240}
241
242static int ppc_cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
243 struct scatterlist *src, unsigned int nbytes)
244{
245 struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
246 struct blkcipher_walk walk;
247 unsigned int ubytes;
248 int err;
249
250 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
251 blkcipher_walk_init(&walk, dst, src, nbytes);
252 err = blkcipher_walk_virt(desc, &walk);
253
254 while ((nbytes = walk.nbytes)) {
255 ubytes = nbytes > MAX_BYTES ?
256 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
257 nbytes -= ubytes;
258
259 spe_begin();
260 ppc_encrypt_cbc(walk.dst.virt.addr, walk.src.virt.addr,
261 ctx->key_enc, ctx->rounds, nbytes, walk.iv);
262 spe_end();
263
264 err = blkcipher_walk_done(desc, &walk, ubytes);
265 }
266
267 return err;
268}
269
270static int ppc_cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
271 struct scatterlist *src, unsigned int nbytes)
272{
273 struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
274 struct blkcipher_walk walk;
275 unsigned int ubytes;
276 int err;
277
278 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
279 blkcipher_walk_init(&walk, dst, src, nbytes);
280 err = blkcipher_walk_virt(desc, &walk);
281
282 while ((nbytes = walk.nbytes)) {
283 ubytes = nbytes > MAX_BYTES ?
284 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
285 nbytes -= ubytes;
286
287 spe_begin();
288 ppc_decrypt_cbc(walk.dst.virt.addr, walk.src.virt.addr,
289 ctx->key_dec, ctx->rounds, nbytes, walk.iv);
290 spe_end();
291
292 err = blkcipher_walk_done(desc, &walk, ubytes);
293 }
294
295 return err;
296}
297
298static int ppc_ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
299 struct scatterlist *src, unsigned int nbytes)
300{
301 struct ppc_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
302 struct blkcipher_walk walk;
303 unsigned int pbytes, ubytes;
304 int err;
305
306 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
307 blkcipher_walk_init(&walk, dst, src, nbytes);
308 err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
309
310 while ((pbytes = walk.nbytes)) {
311 pbytes = pbytes > MAX_BYTES ? MAX_BYTES : pbytes;
312 pbytes = pbytes == nbytes ?
313 nbytes : pbytes & ~(AES_BLOCK_SIZE - 1);
314 ubytes = walk.nbytes - pbytes;
315
316 spe_begin();
317 ppc_crypt_ctr(walk.dst.virt.addr, walk.src.virt.addr,
318 ctx->key_enc, ctx->rounds, pbytes , walk.iv);
319 spe_end();
320
321 nbytes -= pbytes;
322 err = blkcipher_walk_done(desc, &walk, ubytes);
323 }
324
325 return err;
326}
327
328static int ppc_xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
329 struct scatterlist *src, unsigned int nbytes)
330{
331 struct ppc_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
332 struct blkcipher_walk walk;
333 unsigned int ubytes;
334 int err;
335 u32 *twk;
336
337 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
338 blkcipher_walk_init(&walk, dst, src, nbytes);
339 err = blkcipher_walk_virt(desc, &walk);
340 twk = ctx->key_twk;
341
342 while ((nbytes = walk.nbytes)) {
343 ubytes = nbytes > MAX_BYTES ?
344 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
345 nbytes -= ubytes;
346
347 spe_begin();
348 ppc_encrypt_xts(walk.dst.virt.addr, walk.src.virt.addr,
349 ctx->key_enc, ctx->rounds, nbytes, walk.iv, twk);
350 spe_end();
351
352 twk = NULL;
353 err = blkcipher_walk_done(desc, &walk, ubytes);
354 }
355
356 return err;
357}
358
359static int ppc_xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
360 struct scatterlist *src, unsigned int nbytes)
361{
362 struct ppc_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
363 struct blkcipher_walk walk;
364 unsigned int ubytes;
365 int err;
366 u32 *twk;
367
368 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
369 blkcipher_walk_init(&walk, dst, src, nbytes);
370 err = blkcipher_walk_virt(desc, &walk);
371 twk = ctx->key_twk;
372
373 while ((nbytes = walk.nbytes)) {
374 ubytes = nbytes > MAX_BYTES ?
375 nbytes - MAX_BYTES : nbytes & (AES_BLOCK_SIZE - 1);
376 nbytes -= ubytes;
377
378 spe_begin();
379 ppc_decrypt_xts(walk.dst.virt.addr, walk.src.virt.addr,
380 ctx->key_dec, ctx->rounds, nbytes, walk.iv, twk);
381 spe_end();
382
383 twk = NULL;
384 err = blkcipher_walk_done(desc, &walk, ubytes);
385 }
386
387 return err;
388}
389
390/*
391 * Algorithm definitions. Disabling alignment (cra_alignmask=0) was chosen
392 * because the e500 platform can handle unaligned reads/writes very efficently.
393 * This improves IPsec thoughput by another few percent. Additionally we assume
394 * that AES context is always aligned to at least 8 bytes because it is created
395 * with kmalloc() in the crypto infrastructure
396 *
397 */
398static struct crypto_alg aes_algs[] = { {
399 .cra_name = "aes",
400 .cra_driver_name = "aes-ppc-spe",
401 .cra_priority = 300,
402 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
403 .cra_blocksize = AES_BLOCK_SIZE,
404 .cra_ctxsize = sizeof(struct ppc_aes_ctx),
405 .cra_alignmask = 0,
406 .cra_module = THIS_MODULE,
407 .cra_u = {
408 .cipher = {
409 .cia_min_keysize = AES_MIN_KEY_SIZE,
410 .cia_max_keysize = AES_MAX_KEY_SIZE,
411 .cia_setkey = ppc_aes_setkey,
412 .cia_encrypt = ppc_aes_encrypt,
413 .cia_decrypt = ppc_aes_decrypt
414 }
415 }
416}, {
417 .cra_name = "ecb(aes)",
418 .cra_driver_name = "ecb-ppc-spe",
419 .cra_priority = 300,
420 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
421 .cra_blocksize = AES_BLOCK_SIZE,
422 .cra_ctxsize = sizeof(struct ppc_aes_ctx),
423 .cra_alignmask = 0,
424 .cra_type = &crypto_blkcipher_type,
425 .cra_module = THIS_MODULE,
426 .cra_u = {
427 .blkcipher = {
428 .min_keysize = AES_MIN_KEY_SIZE,
429 .max_keysize = AES_MAX_KEY_SIZE,
430 .ivsize = AES_BLOCK_SIZE,
431 .setkey = ppc_aes_setkey,
432 .encrypt = ppc_ecb_encrypt,
433 .decrypt = ppc_ecb_decrypt,
434 }
435 }
436}, {
437 .cra_name = "cbc(aes)",
438 .cra_driver_name = "cbc-ppc-spe",
439 .cra_priority = 300,
440 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
441 .cra_blocksize = AES_BLOCK_SIZE,
442 .cra_ctxsize = sizeof(struct ppc_aes_ctx),
443 .cra_alignmask = 0,
444 .cra_type = &crypto_blkcipher_type,
445 .cra_module = THIS_MODULE,
446 .cra_u = {
447 .blkcipher = {
448 .min_keysize = AES_MIN_KEY_SIZE,
449 .max_keysize = AES_MAX_KEY_SIZE,
450 .ivsize = AES_BLOCK_SIZE,
451 .setkey = ppc_aes_setkey,
452 .encrypt = ppc_cbc_encrypt,
453 .decrypt = ppc_cbc_decrypt,
454 }
455 }
456}, {
457 .cra_name = "ctr(aes)",
458 .cra_driver_name = "ctr-ppc-spe",
459 .cra_priority = 300,
460 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
461 .cra_blocksize = 1,
462 .cra_ctxsize = sizeof(struct ppc_aes_ctx),
463 .cra_alignmask = 0,
464 .cra_type = &crypto_blkcipher_type,
465 .cra_module = THIS_MODULE,
466 .cra_u = {
467 .blkcipher = {
468 .min_keysize = AES_MIN_KEY_SIZE,
469 .max_keysize = AES_MAX_KEY_SIZE,
470 .ivsize = AES_BLOCK_SIZE,
471 .setkey = ppc_aes_setkey,
472 .encrypt = ppc_ctr_crypt,
473 .decrypt = ppc_ctr_crypt,
474 }
475 }
476}, {
477 .cra_name = "xts(aes)",
478 .cra_driver_name = "xts-ppc-spe",
479 .cra_priority = 300,
480 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
481 .cra_blocksize = AES_BLOCK_SIZE,
482 .cra_ctxsize = sizeof(struct ppc_xts_ctx),
483 .cra_alignmask = 0,
484 .cra_type = &crypto_blkcipher_type,
485 .cra_module = THIS_MODULE,
486 .cra_u = {
487 .blkcipher = {
488 .min_keysize = AES_MIN_KEY_SIZE * 2,
489 .max_keysize = AES_MAX_KEY_SIZE * 2,
490 .ivsize = AES_BLOCK_SIZE,
491 .setkey = ppc_xts_setkey,
492 .encrypt = ppc_xts_encrypt,
493 .decrypt = ppc_xts_decrypt,
494 }
495 }
496} };
497
498static int __init ppc_aes_mod_init(void)
499{
500 return crypto_register_algs(aes_algs, ARRAY_SIZE(aes_algs));
501}
502
503static void __exit ppc_aes_mod_fini(void)
504{
505 crypto_unregister_algs(aes_algs, ARRAY_SIZE(aes_algs));
506}
507
508module_init(ppc_aes_mod_init);
509module_exit(ppc_aes_mod_fini);
510
511MODULE_LICENSE("GPL");
512MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS, SPE optimized");
513
514MODULE_ALIAS_CRYPTO("aes");
515MODULE_ALIAS_CRYPTO("ecb(aes)");
516MODULE_ALIAS_CRYPTO("cbc(aes)");
517MODULE_ALIAS_CRYPTO("ctr(aes)");
518MODULE_ALIAS_CRYPTO("xts(aes)");
519MODULE_ALIAS_CRYPTO("aes-ppc-spe");