2 * Bit sliced AES using NEON instructions
4 * Copyright (C) 2016 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
13 #include <crypto/aes.h>
14 #include <crypto/internal/simd.h>
15 #include <crypto/internal/skcipher.h>
16 #include <crypto/xts.h>
17 #include <linux/module.h>
19 #include "aes-ctr-fallback.h"
21 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
22 MODULE_LICENSE("GPL v2");
24 MODULE_ALIAS_CRYPTO("ecb(aes)");
25 MODULE_ALIAS_CRYPTO("cbc(aes)");
26 MODULE_ALIAS_CRYPTO("ctr(aes)");
27 MODULE_ALIAS_CRYPTO("xts(aes)");
29 asmlinkage void aesbs_convert_key(u8 out[], u32 const rk[], int rounds);
31 asmlinkage void aesbs_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[],
32 int rounds, int blocks);
33 asmlinkage void aesbs_ecb_decrypt(u8 out[], u8 const in[], u8 const rk[],
34 int rounds, int blocks);
36 asmlinkage void aesbs_cbc_decrypt(u8 out[], u8 const in[], u8 const rk[],
37 int rounds, int blocks, u8 iv[]);
39 asmlinkage void aesbs_ctr_encrypt(u8 out[], u8 const in[], u8 const rk[],
40 int rounds, int blocks, u8 iv[], u8 final[]);
42 asmlinkage void aesbs_xts_encrypt(u8 out[], u8 const in[], u8 const rk[],
43 int rounds, int blocks, u8 iv[]);
44 asmlinkage void aesbs_xts_decrypt(u8 out[], u8 const in[], u8 const rk[],
45 int rounds, int blocks, u8 iv[]);
47 /* borrowed from aes-neon-blk.ko */
48 asmlinkage void neon_aes_ecb_encrypt(u8 out[], u8 const in[], u32 const rk[],
49 int rounds, int blocks, int first);
50 asmlinkage void neon_aes_cbc_encrypt(u8 out[], u8 const in[], u32 const rk[],
51 int rounds, int blocks, u8 iv[],
55 u8 rk[13 * (8 * AES_BLOCK_SIZE) + 32];
57 } __aligned(AES_BLOCK_SIZE);
59 struct aesbs_cbc_ctx {
61 u32 enc[AES_MAX_KEYLENGTH_U32];
64 struct aesbs_ctr_ctx {
65 struct aesbs_ctx key; /* must be first member */
66 struct crypto_aes_ctx fallback;
69 struct aesbs_xts_ctx {
71 u32 twkey[AES_MAX_KEYLENGTH_U32];
74 static int aesbs_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
77 struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
78 struct crypto_aes_ctx rk;
81 err = crypto_aes_expand_key(&rk, in_key, key_len);
85 ctx->rounds = 6 + key_len / 4;
88 aesbs_convert_key(ctx->rk, rk.key_enc, ctx->rounds);
94 static int __ecb_crypt(struct skcipher_request *req,
95 void (*fn)(u8 out[], u8 const in[], u8 const rk[],
96 int rounds, int blocks))
98 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
99 struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
100 struct skcipher_walk walk;
103 err = skcipher_walk_virt(&walk, req, true);
106 while (walk.nbytes >= AES_BLOCK_SIZE) {
107 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
109 if (walk.nbytes < walk.total)
110 blocks = round_down(blocks,
111 walk.stride / AES_BLOCK_SIZE);
113 fn(walk.dst.virt.addr, walk.src.virt.addr, ctx->rk,
114 ctx->rounds, blocks);
115 err = skcipher_walk_done(&walk,
116 walk.nbytes - blocks * AES_BLOCK_SIZE);
123 static int ecb_encrypt(struct skcipher_request *req)
125 return __ecb_crypt(req, aesbs_ecb_encrypt);
128 static int ecb_decrypt(struct skcipher_request *req)
130 return __ecb_crypt(req, aesbs_ecb_decrypt);
133 static int aesbs_cbc_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
134 unsigned int key_len)
136 struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
137 struct crypto_aes_ctx rk;
140 err = crypto_aes_expand_key(&rk, in_key, key_len);
144 ctx->key.rounds = 6 + key_len / 4;
146 memcpy(ctx->enc, rk.key_enc, sizeof(ctx->enc));
149 aesbs_convert_key(ctx->key.rk, rk.key_enc, ctx->key.rounds);
155 static int cbc_encrypt(struct skcipher_request *req)
157 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
158 struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
159 struct skcipher_walk walk;
162 err = skcipher_walk_virt(&walk, req, true);
165 while (walk.nbytes >= AES_BLOCK_SIZE) {
166 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
168 /* fall back to the non-bitsliced NEON implementation */
169 neon_aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
170 ctx->enc, ctx->key.rounds, blocks, walk.iv,
172 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
179 static int cbc_decrypt(struct skcipher_request *req)
181 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
182 struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
183 struct skcipher_walk walk;
186 err = skcipher_walk_virt(&walk, req, true);
189 while (walk.nbytes >= AES_BLOCK_SIZE) {
190 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
192 if (walk.nbytes < walk.total)
193 blocks = round_down(blocks,
194 walk.stride / AES_BLOCK_SIZE);
196 aesbs_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
197 ctx->key.rk, ctx->key.rounds, blocks,
199 err = skcipher_walk_done(&walk,
200 walk.nbytes - blocks * AES_BLOCK_SIZE);
207 static int aesbs_ctr_setkey_sync(struct crypto_skcipher *tfm, const u8 *in_key,
208 unsigned int key_len)
210 struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
213 err = crypto_aes_expand_key(&ctx->fallback, in_key, key_len);
217 ctx->key.rounds = 6 + key_len / 4;
220 aesbs_convert_key(ctx->key.rk, ctx->fallback.key_enc, ctx->key.rounds);
226 static int ctr_encrypt(struct skcipher_request *req)
228 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
229 struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
230 struct skcipher_walk walk;
231 u8 buf[AES_BLOCK_SIZE];
234 err = skcipher_walk_virt(&walk, req, true);
237 while (walk.nbytes > 0) {
238 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
239 u8 *final = (walk.total % AES_BLOCK_SIZE) ? buf : NULL;
241 if (walk.nbytes < walk.total) {
242 blocks = round_down(blocks,
243 walk.stride / AES_BLOCK_SIZE);
247 aesbs_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
248 ctx->rk, ctx->rounds, blocks, walk.iv, final);
251 u8 *dst = walk.dst.virt.addr + blocks * AES_BLOCK_SIZE;
252 u8 *src = walk.src.virt.addr + blocks * AES_BLOCK_SIZE;
254 crypto_xor_cpy(dst, src, final,
255 walk.total % AES_BLOCK_SIZE);
257 err = skcipher_walk_done(&walk, 0);
260 err = skcipher_walk_done(&walk,
261 walk.nbytes - blocks * AES_BLOCK_SIZE);
268 static int aesbs_xts_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
269 unsigned int key_len)
271 struct aesbs_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
272 struct crypto_aes_ctx rk;
275 err = xts_verify_key(tfm, in_key, key_len);
280 err = crypto_aes_expand_key(&rk, in_key + key_len, key_len);
284 memcpy(ctx->twkey, rk.key_enc, sizeof(ctx->twkey));
286 return aesbs_setkey(tfm, in_key, key_len);
289 static int ctr_encrypt_sync(struct skcipher_request *req)
291 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
292 struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
295 return aes_ctr_encrypt_fallback(&ctx->fallback, req);
297 return ctr_encrypt(req);
300 static int __xts_crypt(struct skcipher_request *req,
301 void (*fn)(u8 out[], u8 const in[], u8 const rk[],
302 int rounds, int blocks, u8 iv[]))
304 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
305 struct aesbs_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
306 struct skcipher_walk walk;
309 err = skcipher_walk_virt(&walk, req, true);
315 neon_aes_ecb_encrypt(walk.iv, walk.iv, ctx->twkey,
316 ctx->key.rounds, 1, 1);
318 while (walk.nbytes >= AES_BLOCK_SIZE) {
319 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
321 if (walk.nbytes < walk.total)
322 blocks = round_down(blocks,
323 walk.stride / AES_BLOCK_SIZE);
325 fn(walk.dst.virt.addr, walk.src.virt.addr, ctx->key.rk,
326 ctx->key.rounds, blocks, walk.iv);
327 err = skcipher_walk_done(&walk,
328 walk.nbytes - blocks * AES_BLOCK_SIZE);
335 static int xts_encrypt(struct skcipher_request *req)
337 return __xts_crypt(req, aesbs_xts_encrypt);
340 static int xts_decrypt(struct skcipher_request *req)
342 return __xts_crypt(req, aesbs_xts_decrypt);
345 static struct skcipher_alg aes_algs[] = { {
346 .base.cra_name = "__ecb(aes)",
347 .base.cra_driver_name = "__ecb-aes-neonbs",
348 .base.cra_priority = 250,
349 .base.cra_blocksize = AES_BLOCK_SIZE,
350 .base.cra_ctxsize = sizeof(struct aesbs_ctx),
351 .base.cra_module = THIS_MODULE,
352 .base.cra_flags = CRYPTO_ALG_INTERNAL,
354 .min_keysize = AES_MIN_KEY_SIZE,
355 .max_keysize = AES_MAX_KEY_SIZE,
356 .walksize = 8 * AES_BLOCK_SIZE,
357 .setkey = aesbs_setkey,
358 .encrypt = ecb_encrypt,
359 .decrypt = ecb_decrypt,
361 .base.cra_name = "__cbc(aes)",
362 .base.cra_driver_name = "__cbc-aes-neonbs",
363 .base.cra_priority = 250,
364 .base.cra_blocksize = AES_BLOCK_SIZE,
365 .base.cra_ctxsize = sizeof(struct aesbs_cbc_ctx),
366 .base.cra_module = THIS_MODULE,
367 .base.cra_flags = CRYPTO_ALG_INTERNAL,
369 .min_keysize = AES_MIN_KEY_SIZE,
370 .max_keysize = AES_MAX_KEY_SIZE,
371 .walksize = 8 * AES_BLOCK_SIZE,
372 .ivsize = AES_BLOCK_SIZE,
373 .setkey = aesbs_cbc_setkey,
374 .encrypt = cbc_encrypt,
375 .decrypt = cbc_decrypt,
377 .base.cra_name = "__ctr(aes)",
378 .base.cra_driver_name = "__ctr-aes-neonbs",
379 .base.cra_priority = 250,
380 .base.cra_blocksize = 1,
381 .base.cra_ctxsize = sizeof(struct aesbs_ctx),
382 .base.cra_module = THIS_MODULE,
383 .base.cra_flags = CRYPTO_ALG_INTERNAL,
385 .min_keysize = AES_MIN_KEY_SIZE,
386 .max_keysize = AES_MAX_KEY_SIZE,
387 .chunksize = AES_BLOCK_SIZE,
388 .walksize = 8 * AES_BLOCK_SIZE,
389 .ivsize = AES_BLOCK_SIZE,
390 .setkey = aesbs_setkey,
391 .encrypt = ctr_encrypt,
392 .decrypt = ctr_encrypt,
394 .base.cra_name = "ctr(aes)",
395 .base.cra_driver_name = "ctr-aes-neonbs",
396 .base.cra_priority = 250 - 1,
397 .base.cra_blocksize = 1,
398 .base.cra_ctxsize = sizeof(struct aesbs_ctr_ctx),
399 .base.cra_module = THIS_MODULE,
401 .min_keysize = AES_MIN_KEY_SIZE,
402 .max_keysize = AES_MAX_KEY_SIZE,
403 .chunksize = AES_BLOCK_SIZE,
404 .walksize = 8 * AES_BLOCK_SIZE,
405 .ivsize = AES_BLOCK_SIZE,
406 .setkey = aesbs_ctr_setkey_sync,
407 .encrypt = ctr_encrypt_sync,
408 .decrypt = ctr_encrypt_sync,
410 .base.cra_name = "__xts(aes)",
411 .base.cra_driver_name = "__xts-aes-neonbs",
412 .base.cra_priority = 250,
413 .base.cra_blocksize = AES_BLOCK_SIZE,
414 .base.cra_ctxsize = sizeof(struct aesbs_xts_ctx),
415 .base.cra_module = THIS_MODULE,
416 .base.cra_flags = CRYPTO_ALG_INTERNAL,
418 .min_keysize = 2 * AES_MIN_KEY_SIZE,
419 .max_keysize = 2 * AES_MAX_KEY_SIZE,
420 .walksize = 8 * AES_BLOCK_SIZE,
421 .ivsize = AES_BLOCK_SIZE,
422 .setkey = aesbs_xts_setkey,
423 .encrypt = xts_encrypt,
424 .decrypt = xts_decrypt,
427 static struct simd_skcipher_alg *aes_simd_algs[ARRAY_SIZE(aes_algs)];
429 static void aes_exit(void)
433 for (i = 0; i < ARRAY_SIZE(aes_simd_algs); i++)
434 if (aes_simd_algs[i])
435 simd_skcipher_free(aes_simd_algs[i]);
437 crypto_unregister_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
440 static int __init aes_init(void)
442 struct simd_skcipher_alg *simd;
443 const char *basename;
449 if (!(elf_hwcap & HWCAP_ASIMD))
452 err = crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
456 for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
457 if (!(aes_algs[i].base.cra_flags & CRYPTO_ALG_INTERNAL))
460 algname = aes_algs[i].base.cra_name + 2;
461 drvname = aes_algs[i].base.cra_driver_name + 2;
462 basename = aes_algs[i].base.cra_driver_name;
463 simd = simd_skcipher_create_compat(algname, drvname, basename);
466 goto unregister_simds;
468 aes_simd_algs[i] = simd;
477 module_init(aes_init);
478 module_exit(aes_exit);