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);
50 asmlinkage void neon_aes_cbc_encrypt(u8 out[], u8 const in[], u32 const rk[],
51 int rounds, int blocks, u8 iv[]);
54 u8 rk[13 * (8 * AES_BLOCK_SIZE) + 32];
56 } __aligned(AES_BLOCK_SIZE);
58 struct aesbs_cbc_ctx {
60 u32 enc[AES_MAX_KEYLENGTH_U32];
63 struct aesbs_ctr_ctx {
64 struct aesbs_ctx key; /* must be first member */
65 struct crypto_aes_ctx fallback;
68 struct aesbs_xts_ctx {
70 u32 twkey[AES_MAX_KEYLENGTH_U32];
73 static int aesbs_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
76 struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
77 struct crypto_aes_ctx rk;
80 err = crypto_aes_expand_key(&rk, in_key, key_len);
84 ctx->rounds = 6 + key_len / 4;
87 aesbs_convert_key(ctx->rk, rk.key_enc, ctx->rounds);
93 static int __ecb_crypt(struct skcipher_request *req,
94 void (*fn)(u8 out[], u8 const in[], u8 const rk[],
95 int rounds, int blocks))
97 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
98 struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
99 struct skcipher_walk walk;
102 err = skcipher_walk_virt(&walk, req, false);
104 while (walk.nbytes >= AES_BLOCK_SIZE) {
105 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
107 if (walk.nbytes < walk.total)
108 blocks = round_down(blocks,
109 walk.stride / AES_BLOCK_SIZE);
112 fn(walk.dst.virt.addr, walk.src.virt.addr, ctx->rk,
113 ctx->rounds, blocks);
115 err = skcipher_walk_done(&walk,
116 walk.nbytes - blocks * AES_BLOCK_SIZE);
122 static int ecb_encrypt(struct skcipher_request *req)
124 return __ecb_crypt(req, aesbs_ecb_encrypt);
127 static int ecb_decrypt(struct skcipher_request *req)
129 return __ecb_crypt(req, aesbs_ecb_decrypt);
132 static int aesbs_cbc_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
133 unsigned int key_len)
135 struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
136 struct crypto_aes_ctx rk;
139 err = crypto_aes_expand_key(&rk, in_key, key_len);
143 ctx->key.rounds = 6 + key_len / 4;
145 memcpy(ctx->enc, rk.key_enc, sizeof(ctx->enc));
148 aesbs_convert_key(ctx->key.rk, rk.key_enc, ctx->key.rounds);
154 static int cbc_encrypt(struct skcipher_request *req)
156 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
157 struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
158 struct skcipher_walk walk;
161 err = skcipher_walk_virt(&walk, req, false);
163 while (walk.nbytes >= AES_BLOCK_SIZE) {
164 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
166 /* fall back to the non-bitsliced NEON implementation */
168 neon_aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
169 ctx->enc, ctx->key.rounds, blocks,
172 err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
177 static int cbc_decrypt(struct skcipher_request *req)
179 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
180 struct aesbs_cbc_ctx *ctx = crypto_skcipher_ctx(tfm);
181 struct skcipher_walk walk;
184 err = skcipher_walk_virt(&walk, req, false);
186 while (walk.nbytes >= AES_BLOCK_SIZE) {
187 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
189 if (walk.nbytes < walk.total)
190 blocks = round_down(blocks,
191 walk.stride / AES_BLOCK_SIZE);
194 aesbs_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
195 ctx->key.rk, ctx->key.rounds, blocks,
198 err = skcipher_walk_done(&walk,
199 walk.nbytes - blocks * AES_BLOCK_SIZE);
205 static int aesbs_ctr_setkey_sync(struct crypto_skcipher *tfm, const u8 *in_key,
206 unsigned int key_len)
208 struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
211 err = crypto_aes_expand_key(&ctx->fallback, in_key, key_len);
215 ctx->key.rounds = 6 + key_len / 4;
218 aesbs_convert_key(ctx->key.rk, ctx->fallback.key_enc, ctx->key.rounds);
224 static int ctr_encrypt(struct skcipher_request *req)
226 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
227 struct aesbs_ctx *ctx = crypto_skcipher_ctx(tfm);
228 struct skcipher_walk walk;
229 u8 buf[AES_BLOCK_SIZE];
232 err = skcipher_walk_virt(&walk, req, false);
234 while (walk.nbytes > 0) {
235 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
236 u8 *final = (walk.total % AES_BLOCK_SIZE) ? buf : NULL;
238 if (walk.nbytes < walk.total) {
239 blocks = round_down(blocks,
240 walk.stride / AES_BLOCK_SIZE);
245 aesbs_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
246 ctx->rk, ctx->rounds, blocks, walk.iv, final);
250 u8 *dst = walk.dst.virt.addr + blocks * AES_BLOCK_SIZE;
251 u8 *src = walk.src.virt.addr + blocks * AES_BLOCK_SIZE;
253 crypto_xor_cpy(dst, src, final,
254 walk.total % AES_BLOCK_SIZE);
256 err = skcipher_walk_done(&walk, 0);
259 err = skcipher_walk_done(&walk,
260 walk.nbytes - blocks * AES_BLOCK_SIZE);
265 static int aesbs_xts_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
266 unsigned int key_len)
268 struct aesbs_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
269 struct crypto_aes_ctx rk;
272 err = xts_verify_key(tfm, in_key, key_len);
277 err = crypto_aes_expand_key(&rk, in_key + key_len, key_len);
281 memcpy(ctx->twkey, rk.key_enc, sizeof(ctx->twkey));
283 return aesbs_setkey(tfm, in_key, key_len);
286 static int ctr_encrypt_sync(struct skcipher_request *req)
288 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
289 struct aesbs_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
291 if (!crypto_simd_usable())
292 return aes_ctr_encrypt_fallback(&ctx->fallback, req);
294 return ctr_encrypt(req);
297 static int __xts_crypt(struct skcipher_request *req,
298 void (*fn)(u8 out[], u8 const in[], u8 const rk[],
299 int rounds, int blocks, u8 iv[]))
301 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
302 struct aesbs_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
303 struct skcipher_walk walk;
306 err = skcipher_walk_virt(&walk, req, false);
311 neon_aes_ecb_encrypt(walk.iv, walk.iv, ctx->twkey, ctx->key.rounds, 1);
314 while (walk.nbytes >= AES_BLOCK_SIZE) {
315 unsigned int blocks = walk.nbytes / AES_BLOCK_SIZE;
317 if (walk.nbytes < walk.total)
318 blocks = round_down(blocks,
319 walk.stride / AES_BLOCK_SIZE);
322 fn(walk.dst.virt.addr, walk.src.virt.addr, ctx->key.rk,
323 ctx->key.rounds, blocks, walk.iv);
325 err = skcipher_walk_done(&walk,
326 walk.nbytes - blocks * AES_BLOCK_SIZE);
331 static int xts_encrypt(struct skcipher_request *req)
333 return __xts_crypt(req, aesbs_xts_encrypt);
336 static int xts_decrypt(struct skcipher_request *req)
338 return __xts_crypt(req, aesbs_xts_decrypt);
341 static struct skcipher_alg aes_algs[] = { {
342 .base.cra_name = "__ecb(aes)",
343 .base.cra_driver_name = "__ecb-aes-neonbs",
344 .base.cra_priority = 250,
345 .base.cra_blocksize = AES_BLOCK_SIZE,
346 .base.cra_ctxsize = sizeof(struct aesbs_ctx),
347 .base.cra_module = THIS_MODULE,
348 .base.cra_flags = CRYPTO_ALG_INTERNAL,
350 .min_keysize = AES_MIN_KEY_SIZE,
351 .max_keysize = AES_MAX_KEY_SIZE,
352 .walksize = 8 * AES_BLOCK_SIZE,
353 .setkey = aesbs_setkey,
354 .encrypt = ecb_encrypt,
355 .decrypt = ecb_decrypt,
357 .base.cra_name = "__cbc(aes)",
358 .base.cra_driver_name = "__cbc-aes-neonbs",
359 .base.cra_priority = 250,
360 .base.cra_blocksize = AES_BLOCK_SIZE,
361 .base.cra_ctxsize = sizeof(struct aesbs_cbc_ctx),
362 .base.cra_module = THIS_MODULE,
363 .base.cra_flags = CRYPTO_ALG_INTERNAL,
365 .min_keysize = AES_MIN_KEY_SIZE,
366 .max_keysize = AES_MAX_KEY_SIZE,
367 .walksize = 8 * AES_BLOCK_SIZE,
368 .ivsize = AES_BLOCK_SIZE,
369 .setkey = aesbs_cbc_setkey,
370 .encrypt = cbc_encrypt,
371 .decrypt = cbc_decrypt,
373 .base.cra_name = "__ctr(aes)",
374 .base.cra_driver_name = "__ctr-aes-neonbs",
375 .base.cra_priority = 250,
376 .base.cra_blocksize = 1,
377 .base.cra_ctxsize = sizeof(struct aesbs_ctx),
378 .base.cra_module = THIS_MODULE,
379 .base.cra_flags = CRYPTO_ALG_INTERNAL,
381 .min_keysize = AES_MIN_KEY_SIZE,
382 .max_keysize = AES_MAX_KEY_SIZE,
383 .chunksize = AES_BLOCK_SIZE,
384 .walksize = 8 * AES_BLOCK_SIZE,
385 .ivsize = AES_BLOCK_SIZE,
386 .setkey = aesbs_setkey,
387 .encrypt = ctr_encrypt,
388 .decrypt = ctr_encrypt,
390 .base.cra_name = "ctr(aes)",
391 .base.cra_driver_name = "ctr-aes-neonbs",
392 .base.cra_priority = 250 - 1,
393 .base.cra_blocksize = 1,
394 .base.cra_ctxsize = sizeof(struct aesbs_ctr_ctx),
395 .base.cra_module = THIS_MODULE,
397 .min_keysize = AES_MIN_KEY_SIZE,
398 .max_keysize = AES_MAX_KEY_SIZE,
399 .chunksize = AES_BLOCK_SIZE,
400 .walksize = 8 * AES_BLOCK_SIZE,
401 .ivsize = AES_BLOCK_SIZE,
402 .setkey = aesbs_ctr_setkey_sync,
403 .encrypt = ctr_encrypt_sync,
404 .decrypt = ctr_encrypt_sync,
406 .base.cra_name = "__xts(aes)",
407 .base.cra_driver_name = "__xts-aes-neonbs",
408 .base.cra_priority = 250,
409 .base.cra_blocksize = AES_BLOCK_SIZE,
410 .base.cra_ctxsize = sizeof(struct aesbs_xts_ctx),
411 .base.cra_module = THIS_MODULE,
412 .base.cra_flags = CRYPTO_ALG_INTERNAL,
414 .min_keysize = 2 * AES_MIN_KEY_SIZE,
415 .max_keysize = 2 * AES_MAX_KEY_SIZE,
416 .walksize = 8 * AES_BLOCK_SIZE,
417 .ivsize = AES_BLOCK_SIZE,
418 .setkey = aesbs_xts_setkey,
419 .encrypt = xts_encrypt,
420 .decrypt = xts_decrypt,
423 static struct simd_skcipher_alg *aes_simd_algs[ARRAY_SIZE(aes_algs)];
425 static void aes_exit(void)
429 for (i = 0; i < ARRAY_SIZE(aes_simd_algs); i++)
430 if (aes_simd_algs[i])
431 simd_skcipher_free(aes_simd_algs[i]);
433 crypto_unregister_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
436 static int __init aes_init(void)
438 struct simd_skcipher_alg *simd;
439 const char *basename;
445 if (!cpu_have_named_feature(ASIMD))
448 err = crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
452 for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
453 if (!(aes_algs[i].base.cra_flags & CRYPTO_ALG_INTERNAL))
456 algname = aes_algs[i].base.cra_name + 2;
457 drvname = aes_algs[i].base.cra_driver_name + 2;
458 basename = aes_algs[i].base.cra_driver_name;
459 simd = simd_skcipher_create_compat(algname, drvname, basename);
462 goto unregister_simds;
464 aes_simd_algs[i] = simd;
473 module_init(aes_init);
474 module_exit(aes_exit);