1
2
3
4
5
6
7
8
9
10
11#include <asm/hwcap.h>
12#include <asm/neon.h>
13#include <asm/hwcap.h>
14#include <crypto/aes.h>
15#include <crypto/internal/simd.h>
16#include <crypto/internal/skcipher.h>
17#include <linux/cpufeature.h>
18#include <linux/module.h>
19#include <crypto/xts.h>
20
21MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS using ARMv8 Crypto Extensions");
22MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
23MODULE_LICENSE("GPL v2");
24
25
26asmlinkage u32 ce_aes_sub(u32 input);
27asmlinkage void ce_aes_invert(void *dst, void *src);
28
29asmlinkage void ce_aes_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[],
30 int rounds, int blocks);
31asmlinkage void ce_aes_ecb_decrypt(u8 out[], u8 const in[], u8 const rk[],
32 int rounds, int blocks);
33
34asmlinkage void ce_aes_cbc_encrypt(u8 out[], u8 const in[], u8 const rk[],
35 int rounds, int blocks, u8 iv[]);
36asmlinkage void ce_aes_cbc_decrypt(u8 out[], u8 const in[], u8 const rk[],
37 int rounds, int blocks, u8 iv[]);
38
39asmlinkage void ce_aes_ctr_encrypt(u8 out[], u8 const in[], u8 const rk[],
40 int rounds, int blocks, u8 ctr[]);
41
42asmlinkage void ce_aes_xts_encrypt(u8 out[], u8 const in[], u8 const rk1[],
43 int rounds, int blocks, u8 iv[],
44 u8 const rk2[], int first);
45asmlinkage void ce_aes_xts_decrypt(u8 out[], u8 const in[], u8 const rk1[],
46 int rounds, int blocks, u8 iv[],
47 u8 const rk2[], int first);
48
49struct aes_block {
50 u8 b[AES_BLOCK_SIZE];
51};
52
53static int num_rounds(struct crypto_aes_ctx *ctx)
54{
55
56
57
58
59
60
61
62 return 6 + ctx->key_length / 4;
63}
64
65static int ce_aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
66 unsigned int key_len)
67{
68
69
70
71 static u8 const rcon[] = {
72 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36,
73 };
74
75 u32 kwords = key_len / sizeof(u32);
76 struct aes_block *key_enc, *key_dec;
77 int i, j;
78
79 if (key_len != AES_KEYSIZE_128 &&
80 key_len != AES_KEYSIZE_192 &&
81 key_len != AES_KEYSIZE_256)
82 return -EINVAL;
83
84 memcpy(ctx->key_enc, in_key, key_len);
85 ctx->key_length = key_len;
86
87 kernel_neon_begin();
88 for (i = 0; i < sizeof(rcon); i++) {
89 u32 *rki = ctx->key_enc + (i * kwords);
90 u32 *rko = rki + kwords;
91
92#ifndef CONFIG_CPU_BIG_ENDIAN
93 rko[0] = ror32(ce_aes_sub(rki[kwords - 1]), 8);
94 rko[0] = rko[0] ^ rki[0] ^ rcon[i];
95#else
96 rko[0] = rol32(ce_aes_sub(rki[kwords - 1]), 8);
97 rko[0] = rko[0] ^ rki[0] ^ (rcon[i] << 24);
98#endif
99 rko[1] = rko[0] ^ rki[1];
100 rko[2] = rko[1] ^ rki[2];
101 rko[3] = rko[2] ^ rki[3];
102
103 if (key_len == AES_KEYSIZE_192) {
104 if (i >= 7)
105 break;
106 rko[4] = rko[3] ^ rki[4];
107 rko[5] = rko[4] ^ rki[5];
108 } else if (key_len == AES_KEYSIZE_256) {
109 if (i >= 6)
110 break;
111 rko[4] = ce_aes_sub(rko[3]) ^ rki[4];
112 rko[5] = rko[4] ^ rki[5];
113 rko[6] = rko[5] ^ rki[6];
114 rko[7] = rko[6] ^ rki[7];
115 }
116 }
117
118
119
120
121
122
123
124 key_enc = (struct aes_block *)ctx->key_enc;
125 key_dec = (struct aes_block *)ctx->key_dec;
126 j = num_rounds(ctx);
127
128 key_dec[0] = key_enc[j];
129 for (i = 1, j--; j > 0; i++, j--)
130 ce_aes_invert(key_dec + i, key_enc + j);
131 key_dec[i] = key_enc[0];
132
133 kernel_neon_end();
134 return 0;
135}
136
137static int ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
138 unsigned int key_len)
139{
140 struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
141 int ret;
142
143 ret = ce_aes_expandkey(ctx, in_key, key_len);
144 if (!ret)
145 return 0;
146
147 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
148 return -EINVAL;
149}
150
151struct crypto_aes_xts_ctx {
152 struct crypto_aes_ctx key1;
153 struct crypto_aes_ctx __aligned(8) key2;
154};
155
156static int xts_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
157 unsigned int key_len)
158{
159 struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
160 int ret;
161
162 ret = xts_verify_key(tfm, in_key, key_len);
163 if (ret)
164 return ret;
165
166 ret = ce_aes_expandkey(&ctx->key1, in_key, key_len / 2);
167 if (!ret)
168 ret = ce_aes_expandkey(&ctx->key2, &in_key[key_len / 2],
169 key_len / 2);
170 if (!ret)
171 return 0;
172
173 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
174 return -EINVAL;
175}
176
177static int ecb_encrypt(struct skcipher_request *req)
178{
179 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
180 struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
181 struct skcipher_walk walk;
182 unsigned int blocks;
183 int err;
184
185 err = skcipher_walk_virt(&walk, req, true);
186
187 kernel_neon_begin();
188 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
189 ce_aes_ecb_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
190 (u8 *)ctx->key_enc, num_rounds(ctx), blocks);
191 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
192 }
193 kernel_neon_end();
194 return err;
195}
196
197static int ecb_decrypt(struct skcipher_request *req)
198{
199 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
200 struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
201 struct skcipher_walk walk;
202 unsigned int blocks;
203 int err;
204
205 err = skcipher_walk_virt(&walk, req, true);
206
207 kernel_neon_begin();
208 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
209 ce_aes_ecb_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
210 (u8 *)ctx->key_dec, num_rounds(ctx), blocks);
211 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
212 }
213 kernel_neon_end();
214 return err;
215}
216
217static int cbc_encrypt(struct skcipher_request *req)
218{
219 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
220 struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
221 struct skcipher_walk walk;
222 unsigned int blocks;
223 int err;
224
225 err = skcipher_walk_virt(&walk, req, true);
226
227 kernel_neon_begin();
228 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
229 ce_aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
230 (u8 *)ctx->key_enc, num_rounds(ctx), blocks,
231 walk.iv);
232 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
233 }
234 kernel_neon_end();
235 return err;
236}
237
238static int cbc_decrypt(struct skcipher_request *req)
239{
240 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
241 struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
242 struct skcipher_walk walk;
243 unsigned int blocks;
244 int err;
245
246 err = skcipher_walk_virt(&walk, req, true);
247
248 kernel_neon_begin();
249 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
250 ce_aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
251 (u8 *)ctx->key_dec, num_rounds(ctx), blocks,
252 walk.iv);
253 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
254 }
255 kernel_neon_end();
256 return err;
257}
258
259static int ctr_encrypt(struct skcipher_request *req)
260{
261 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
262 struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
263 struct skcipher_walk walk;
264 int err, blocks;
265
266 err = skcipher_walk_virt(&walk, req, true);
267
268 kernel_neon_begin();
269 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
270 ce_aes_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
271 (u8 *)ctx->key_enc, num_rounds(ctx), blocks,
272 walk.iv);
273 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
274 }
275 if (walk.nbytes) {
276 u8 __aligned(8) tail[AES_BLOCK_SIZE];
277 unsigned int nbytes = walk.nbytes;
278 u8 *tdst = walk.dst.virt.addr;
279 u8 *tsrc = walk.src.virt.addr;
280
281
282
283
284 blocks = -1;
285
286 ce_aes_ctr_encrypt(tail, NULL, (u8 *)ctx->key_enc,
287 num_rounds(ctx), blocks, walk.iv);
288 crypto_xor_cpy(tdst, tsrc, tail, nbytes);
289 err = skcipher_walk_done(&walk, 0);
290 }
291 kernel_neon_end();
292
293 return err;
294}
295
296static int xts_encrypt(struct skcipher_request *req)
297{
298 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
299 struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
300 int err, first, rounds = num_rounds(&ctx->key1);
301 struct skcipher_walk walk;
302 unsigned int blocks;
303
304 err = skcipher_walk_virt(&walk, req, true);
305
306 kernel_neon_begin();
307 for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
308 ce_aes_xts_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
309 (u8 *)ctx->key1.key_enc, rounds, blocks,
310 walk.iv, (u8 *)ctx->key2.key_enc, first);
311 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
312 }
313 kernel_neon_end();
314
315 return err;
316}
317
318static int xts_decrypt(struct skcipher_request *req)
319{
320 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
321 struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
322 int err, first, rounds = num_rounds(&ctx->key1);
323 struct skcipher_walk walk;
324 unsigned int blocks;
325
326 err = skcipher_walk_virt(&walk, req, true);
327
328 kernel_neon_begin();
329 for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
330 ce_aes_xts_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
331 (u8 *)ctx->key1.key_dec, rounds, blocks,
332 walk.iv, (u8 *)ctx->key2.key_enc, first);
333 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
334 }
335 kernel_neon_end();
336
337 return err;
338}
339
340static struct skcipher_alg aes_algs[] = { {
341 .base = {
342 .cra_name = "__ecb(aes)",
343 .cra_driver_name = "__ecb-aes-ce",
344 .cra_priority = 300,
345 .cra_flags = CRYPTO_ALG_INTERNAL,
346 .cra_blocksize = AES_BLOCK_SIZE,
347 .cra_ctxsize = sizeof(struct crypto_aes_ctx),
348 .cra_module = THIS_MODULE,
349 },
350 .min_keysize = AES_MIN_KEY_SIZE,
351 .max_keysize = AES_MAX_KEY_SIZE,
352 .setkey = ce_aes_setkey,
353 .encrypt = ecb_encrypt,
354 .decrypt = ecb_decrypt,
355}, {
356 .base = {
357 .cra_name = "__cbc(aes)",
358 .cra_driver_name = "__cbc-aes-ce",
359 .cra_priority = 300,
360 .cra_flags = CRYPTO_ALG_INTERNAL,
361 .cra_blocksize = AES_BLOCK_SIZE,
362 .cra_ctxsize = sizeof(struct crypto_aes_ctx),
363 .cra_module = THIS_MODULE,
364 },
365 .min_keysize = AES_MIN_KEY_SIZE,
366 .max_keysize = AES_MAX_KEY_SIZE,
367 .ivsize = AES_BLOCK_SIZE,
368 .setkey = ce_aes_setkey,
369 .encrypt = cbc_encrypt,
370 .decrypt = cbc_decrypt,
371}, {
372 .base = {
373 .cra_name = "__ctr(aes)",
374 .cra_driver_name = "__ctr-aes-ce",
375 .cra_priority = 300,
376 .cra_flags = CRYPTO_ALG_INTERNAL,
377 .cra_blocksize = 1,
378 .cra_ctxsize = sizeof(struct crypto_aes_ctx),
379 .cra_module = THIS_MODULE,
380 },
381 .min_keysize = AES_MIN_KEY_SIZE,
382 .max_keysize = AES_MAX_KEY_SIZE,
383 .ivsize = AES_BLOCK_SIZE,
384 .chunksize = AES_BLOCK_SIZE,
385 .setkey = ce_aes_setkey,
386 .encrypt = ctr_encrypt,
387 .decrypt = ctr_encrypt,
388}, {
389 .base = {
390 .cra_name = "__xts(aes)",
391 .cra_driver_name = "__xts-aes-ce",
392 .cra_priority = 300,
393 .cra_flags = CRYPTO_ALG_INTERNAL,
394 .cra_blocksize = AES_BLOCK_SIZE,
395 .cra_ctxsize = sizeof(struct crypto_aes_xts_ctx),
396 .cra_module = THIS_MODULE,
397 },
398 .min_keysize = 2 * AES_MIN_KEY_SIZE,
399 .max_keysize = 2 * AES_MAX_KEY_SIZE,
400 .ivsize = AES_BLOCK_SIZE,
401 .setkey = xts_set_key,
402 .encrypt = xts_encrypt,
403 .decrypt = xts_decrypt,
404} };
405
406static struct simd_skcipher_alg *aes_simd_algs[ARRAY_SIZE(aes_algs)];
407
408static void aes_exit(void)
409{
410 int i;
411
412 for (i = 0; i < ARRAY_SIZE(aes_simd_algs) && aes_simd_algs[i]; i++)
413 simd_skcipher_free(aes_simd_algs[i]);
414
415 crypto_unregister_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
416}
417
418static int __init aes_init(void)
419{
420 struct simd_skcipher_alg *simd;
421 const char *basename;
422 const char *algname;
423 const char *drvname;
424 int err;
425 int i;
426
427 err = crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
428 if (err)
429 return err;
430
431 for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
432 algname = aes_algs[i].base.cra_name + 2;
433 drvname = aes_algs[i].base.cra_driver_name + 2;
434 basename = aes_algs[i].base.cra_driver_name;
435 simd = simd_skcipher_create_compat(algname, drvname, basename);
436 err = PTR_ERR(simd);
437 if (IS_ERR(simd))
438 goto unregister_simds;
439
440 aes_simd_algs[i] = simd;
441 }
442
443 return 0;
444
445unregister_simds:
446 aes_exit();
447 return err;
448}
449
450module_cpu_feature_match(AES, aes_init);
451module_exit(aes_exit);
452
