lib/genalloc: fix the overflow when size is too big
[linux-2.6-microblaze.git] / crypto / aegis128-core.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * The AEGIS-128 Authenticated-Encryption Algorithm
4  *
5  * Copyright (c) 2017-2018 Ondrej Mosnacek <omosnacek@gmail.com>
6  * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
7  */
8
9 #include <crypto/algapi.h>
10 #include <crypto/internal/aead.h>
11 #include <crypto/internal/simd.h>
12 #include <crypto/internal/skcipher.h>
13 #include <crypto/scatterwalk.h>
14 #include <linux/err.h>
15 #include <linux/init.h>
16 #include <linux/jump_label.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/scatterlist.h>
20
21 #include <asm/simd.h>
22
23 #include "aegis.h"
24
25 #define AEGIS128_NONCE_SIZE 16
26 #define AEGIS128_STATE_BLOCKS 5
27 #define AEGIS128_KEY_SIZE 16
28 #define AEGIS128_MIN_AUTH_SIZE 8
29 #define AEGIS128_MAX_AUTH_SIZE 16
30
31 struct aegis_state {
32         union aegis_block blocks[AEGIS128_STATE_BLOCKS];
33 };
34
35 struct aegis_ctx {
36         union aegis_block key;
37 };
38
39 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_simd);
40
41 static const union aegis_block crypto_aegis_const[2] = {
42         { .words64 = {
43                 cpu_to_le64(U64_C(0x0d08050302010100)),
44                 cpu_to_le64(U64_C(0x6279e99059372215)),
45         } },
46         { .words64 = {
47                 cpu_to_le64(U64_C(0xf12fc26d55183ddb)),
48                 cpu_to_le64(U64_C(0xdd28b57342311120)),
49         } },
50 };
51
52 static bool aegis128_do_simd(void)
53 {
54 #ifdef CONFIG_CRYPTO_AEGIS128_SIMD
55         if (static_branch_likely(&have_simd))
56                 return crypto_simd_usable();
57 #endif
58         return false;
59 }
60
61 bool crypto_aegis128_have_simd(void);
62 void crypto_aegis128_update_simd(struct aegis_state *state, const void *msg);
63 void crypto_aegis128_init_simd(struct aegis_state *state,
64                                const union aegis_block *key,
65                                const u8 *iv);
66 void crypto_aegis128_encrypt_chunk_simd(struct aegis_state *state, u8 *dst,
67                                         const u8 *src, unsigned int size);
68 void crypto_aegis128_decrypt_chunk_simd(struct aegis_state *state, u8 *dst,
69                                         const u8 *src, unsigned int size);
70 int crypto_aegis128_final_simd(struct aegis_state *state,
71                                union aegis_block *tag_xor,
72                                unsigned int assoclen,
73                                unsigned int cryptlen,
74                                unsigned int authsize);
75
76 static void crypto_aegis128_update(struct aegis_state *state)
77 {
78         union aegis_block tmp;
79         unsigned int i;
80
81         tmp = state->blocks[AEGIS128_STATE_BLOCKS - 1];
82         for (i = AEGIS128_STATE_BLOCKS - 1; i > 0; i--)
83                 crypto_aegis_aesenc(&state->blocks[i], &state->blocks[i - 1],
84                                     &state->blocks[i]);
85         crypto_aegis_aesenc(&state->blocks[0], &tmp, &state->blocks[0]);
86 }
87
88 static void crypto_aegis128_update_a(struct aegis_state *state,
89                                      const union aegis_block *msg,
90                                      bool do_simd)
91 {
92         if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) && do_simd) {
93                 crypto_aegis128_update_simd(state, msg);
94                 return;
95         }
96
97         crypto_aegis128_update(state);
98         crypto_aegis_block_xor(&state->blocks[0], msg);
99 }
100
101 static void crypto_aegis128_update_u(struct aegis_state *state, const void *msg,
102                                      bool do_simd)
103 {
104         if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) && do_simd) {
105                 crypto_aegis128_update_simd(state, msg);
106                 return;
107         }
108
109         crypto_aegis128_update(state);
110         crypto_xor(state->blocks[0].bytes, msg, AEGIS_BLOCK_SIZE);
111 }
112
113 static void crypto_aegis128_init(struct aegis_state *state,
114                                  const union aegis_block *key,
115                                  const u8 *iv)
116 {
117         union aegis_block key_iv;
118         unsigned int i;
119
120         key_iv = *key;
121         crypto_xor(key_iv.bytes, iv, AEGIS_BLOCK_SIZE);
122
123         state->blocks[0] = key_iv;
124         state->blocks[1] = crypto_aegis_const[1];
125         state->blocks[2] = crypto_aegis_const[0];
126         state->blocks[3] = *key;
127         state->blocks[4] = *key;
128
129         crypto_aegis_block_xor(&state->blocks[3], &crypto_aegis_const[0]);
130         crypto_aegis_block_xor(&state->blocks[4], &crypto_aegis_const[1]);
131
132         for (i = 0; i < 5; i++) {
133                 crypto_aegis128_update_a(state, key, false);
134                 crypto_aegis128_update_a(state, &key_iv, false);
135         }
136 }
137
138 static void crypto_aegis128_ad(struct aegis_state *state,
139                                const u8 *src, unsigned int size,
140                                bool do_simd)
141 {
142         if (AEGIS_ALIGNED(src)) {
143                 const union aegis_block *src_blk =
144                                 (const union aegis_block *)src;
145
146                 while (size >= AEGIS_BLOCK_SIZE) {
147                         crypto_aegis128_update_a(state, src_blk, do_simd);
148
149                         size -= AEGIS_BLOCK_SIZE;
150                         src_blk++;
151                 }
152         } else {
153                 while (size >= AEGIS_BLOCK_SIZE) {
154                         crypto_aegis128_update_u(state, src, do_simd);
155
156                         size -= AEGIS_BLOCK_SIZE;
157                         src += AEGIS_BLOCK_SIZE;
158                 }
159         }
160 }
161
162 static void crypto_aegis128_wipe_chunk(struct aegis_state *state, u8 *dst,
163                                        const u8 *src, unsigned int size)
164 {
165         memzero_explicit(dst, size);
166 }
167
168 static void crypto_aegis128_encrypt_chunk(struct aegis_state *state, u8 *dst,
169                                           const u8 *src, unsigned int size)
170 {
171         union aegis_block tmp;
172
173         if (AEGIS_ALIGNED(src) && AEGIS_ALIGNED(dst)) {
174                 while (size >= AEGIS_BLOCK_SIZE) {
175                         union aegis_block *dst_blk =
176                                         (union aegis_block *)dst;
177                         const union aegis_block *src_blk =
178                                         (const union aegis_block *)src;
179
180                         tmp = state->blocks[2];
181                         crypto_aegis_block_and(&tmp, &state->blocks[3]);
182                         crypto_aegis_block_xor(&tmp, &state->blocks[4]);
183                         crypto_aegis_block_xor(&tmp, &state->blocks[1]);
184                         crypto_aegis_block_xor(&tmp, src_blk);
185
186                         crypto_aegis128_update_a(state, src_blk, false);
187
188                         *dst_blk = tmp;
189
190                         size -= AEGIS_BLOCK_SIZE;
191                         src += AEGIS_BLOCK_SIZE;
192                         dst += AEGIS_BLOCK_SIZE;
193                 }
194         } else {
195                 while (size >= AEGIS_BLOCK_SIZE) {
196                         tmp = state->blocks[2];
197                         crypto_aegis_block_and(&tmp, &state->blocks[3]);
198                         crypto_aegis_block_xor(&tmp, &state->blocks[4]);
199                         crypto_aegis_block_xor(&tmp, &state->blocks[1]);
200                         crypto_xor(tmp.bytes, src, AEGIS_BLOCK_SIZE);
201
202                         crypto_aegis128_update_u(state, src, false);
203
204                         memcpy(dst, tmp.bytes, AEGIS_BLOCK_SIZE);
205
206                         size -= AEGIS_BLOCK_SIZE;
207                         src += AEGIS_BLOCK_SIZE;
208                         dst += AEGIS_BLOCK_SIZE;
209                 }
210         }
211
212         if (size > 0) {
213                 union aegis_block msg = {};
214                 memcpy(msg.bytes, src, size);
215
216                 tmp = state->blocks[2];
217                 crypto_aegis_block_and(&tmp, &state->blocks[3]);
218                 crypto_aegis_block_xor(&tmp, &state->blocks[4]);
219                 crypto_aegis_block_xor(&tmp, &state->blocks[1]);
220
221                 crypto_aegis128_update_a(state, &msg, false);
222
223                 crypto_aegis_block_xor(&msg, &tmp);
224
225                 memcpy(dst, msg.bytes, size);
226         }
227 }
228
229 static void crypto_aegis128_decrypt_chunk(struct aegis_state *state, u8 *dst,
230                                           const u8 *src, unsigned int size)
231 {
232         union aegis_block tmp;
233
234         if (AEGIS_ALIGNED(src) && AEGIS_ALIGNED(dst)) {
235                 while (size >= AEGIS_BLOCK_SIZE) {
236                         union aegis_block *dst_blk =
237                                         (union aegis_block *)dst;
238                         const union aegis_block *src_blk =
239                                         (const union aegis_block *)src;
240
241                         tmp = state->blocks[2];
242                         crypto_aegis_block_and(&tmp, &state->blocks[3]);
243                         crypto_aegis_block_xor(&tmp, &state->blocks[4]);
244                         crypto_aegis_block_xor(&tmp, &state->blocks[1]);
245                         crypto_aegis_block_xor(&tmp, src_blk);
246
247                         crypto_aegis128_update_a(state, &tmp, false);
248
249                         *dst_blk = tmp;
250
251                         size -= AEGIS_BLOCK_SIZE;
252                         src += AEGIS_BLOCK_SIZE;
253                         dst += AEGIS_BLOCK_SIZE;
254                 }
255         } else {
256                 while (size >= AEGIS_BLOCK_SIZE) {
257                         tmp = state->blocks[2];
258                         crypto_aegis_block_and(&tmp, &state->blocks[3]);
259                         crypto_aegis_block_xor(&tmp, &state->blocks[4]);
260                         crypto_aegis_block_xor(&tmp, &state->blocks[1]);
261                         crypto_xor(tmp.bytes, src, AEGIS_BLOCK_SIZE);
262
263                         crypto_aegis128_update_a(state, &tmp, false);
264
265                         memcpy(dst, tmp.bytes, AEGIS_BLOCK_SIZE);
266
267                         size -= AEGIS_BLOCK_SIZE;
268                         src += AEGIS_BLOCK_SIZE;
269                         dst += AEGIS_BLOCK_SIZE;
270                 }
271         }
272
273         if (size > 0) {
274                 union aegis_block msg = {};
275                 memcpy(msg.bytes, src, size);
276
277                 tmp = state->blocks[2];
278                 crypto_aegis_block_and(&tmp, &state->blocks[3]);
279                 crypto_aegis_block_xor(&tmp, &state->blocks[4]);
280                 crypto_aegis_block_xor(&tmp, &state->blocks[1]);
281                 crypto_aegis_block_xor(&msg, &tmp);
282
283                 memset(msg.bytes + size, 0, AEGIS_BLOCK_SIZE - size);
284
285                 crypto_aegis128_update_a(state, &msg, false);
286
287                 memcpy(dst, msg.bytes, size);
288         }
289 }
290
291 static void crypto_aegis128_process_ad(struct aegis_state *state,
292                                        struct scatterlist *sg_src,
293                                        unsigned int assoclen,
294                                        bool do_simd)
295 {
296         struct scatter_walk walk;
297         union aegis_block buf;
298         unsigned int pos = 0;
299
300         scatterwalk_start(&walk, sg_src);
301         while (assoclen != 0) {
302                 unsigned int size = scatterwalk_clamp(&walk, assoclen);
303                 unsigned int left = size;
304                 void *mapped = scatterwalk_map(&walk);
305                 const u8 *src = (const u8 *)mapped;
306
307                 if (pos + size >= AEGIS_BLOCK_SIZE) {
308                         if (pos > 0) {
309                                 unsigned int fill = AEGIS_BLOCK_SIZE - pos;
310                                 memcpy(buf.bytes + pos, src, fill);
311                                 crypto_aegis128_update_a(state, &buf, do_simd);
312                                 pos = 0;
313                                 left -= fill;
314                                 src += fill;
315                         }
316
317                         crypto_aegis128_ad(state, src, left, do_simd);
318                         src += left & ~(AEGIS_BLOCK_SIZE - 1);
319                         left &= AEGIS_BLOCK_SIZE - 1;
320                 }
321
322                 memcpy(buf.bytes + pos, src, left);
323
324                 pos += left;
325                 assoclen -= size;
326                 scatterwalk_unmap(mapped);
327                 scatterwalk_advance(&walk, size);
328                 scatterwalk_done(&walk, 0, assoclen);
329         }
330
331         if (pos > 0) {
332                 memset(buf.bytes + pos, 0, AEGIS_BLOCK_SIZE - pos);
333                 crypto_aegis128_update_a(state, &buf, do_simd);
334         }
335 }
336
337 static __always_inline
338 int crypto_aegis128_process_crypt(struct aegis_state *state,
339                                   struct skcipher_walk *walk,
340                                   void (*crypt)(struct aegis_state *state,
341                                                 u8 *dst, const u8 *src,
342                                                 unsigned int size))
343 {
344         int err = 0;
345
346         while (walk->nbytes) {
347                 unsigned int nbytes = walk->nbytes;
348
349                 if (nbytes < walk->total)
350                         nbytes = round_down(nbytes, walk->stride);
351
352                 crypt(state, walk->dst.virt.addr, walk->src.virt.addr, nbytes);
353
354                 err = skcipher_walk_done(walk, walk->nbytes - nbytes);
355         }
356         return err;
357 }
358
359 static void crypto_aegis128_final(struct aegis_state *state,
360                                   union aegis_block *tag_xor,
361                                   u64 assoclen, u64 cryptlen)
362 {
363         u64 assocbits = assoclen * 8;
364         u64 cryptbits = cryptlen * 8;
365
366         union aegis_block tmp;
367         unsigned int i;
368
369         tmp.words64[0] = cpu_to_le64(assocbits);
370         tmp.words64[1] = cpu_to_le64(cryptbits);
371
372         crypto_aegis_block_xor(&tmp, &state->blocks[3]);
373
374         for (i = 0; i < 7; i++)
375                 crypto_aegis128_update_a(state, &tmp, false);
376
377         for (i = 0; i < AEGIS128_STATE_BLOCKS; i++)
378                 crypto_aegis_block_xor(tag_xor, &state->blocks[i]);
379 }
380
381 static int crypto_aegis128_setkey(struct crypto_aead *aead, const u8 *key,
382                                   unsigned int keylen)
383 {
384         struct aegis_ctx *ctx = crypto_aead_ctx(aead);
385
386         if (keylen != AEGIS128_KEY_SIZE)
387                 return -EINVAL;
388
389         memcpy(ctx->key.bytes, key, AEGIS128_KEY_SIZE);
390         return 0;
391 }
392
393 static int crypto_aegis128_setauthsize(struct crypto_aead *tfm,
394                                        unsigned int authsize)
395 {
396         if (authsize > AEGIS128_MAX_AUTH_SIZE)
397                 return -EINVAL;
398         if (authsize < AEGIS128_MIN_AUTH_SIZE)
399                 return -EINVAL;
400         return 0;
401 }
402
403 static int crypto_aegis128_encrypt_generic(struct aead_request *req)
404 {
405         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
406         union aegis_block tag = {};
407         unsigned int authsize = crypto_aead_authsize(tfm);
408         struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
409         unsigned int cryptlen = req->cryptlen;
410         struct skcipher_walk walk;
411         struct aegis_state state;
412
413         skcipher_walk_aead_encrypt(&walk, req, false);
414         crypto_aegis128_init(&state, &ctx->key, req->iv);
415         crypto_aegis128_process_ad(&state, req->src, req->assoclen, false);
416         crypto_aegis128_process_crypt(&state, &walk,
417                                       crypto_aegis128_encrypt_chunk);
418         crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen);
419
420         scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen,
421                                  authsize, 1);
422         return 0;
423 }
424
425 static int crypto_aegis128_decrypt_generic(struct aead_request *req)
426 {
427         static const u8 zeros[AEGIS128_MAX_AUTH_SIZE] = {};
428         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
429         union aegis_block tag;
430         unsigned int authsize = crypto_aead_authsize(tfm);
431         unsigned int cryptlen = req->cryptlen - authsize;
432         struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
433         struct skcipher_walk walk;
434         struct aegis_state state;
435
436         scatterwalk_map_and_copy(tag.bytes, req->src, req->assoclen + cryptlen,
437                                  authsize, 0);
438
439         skcipher_walk_aead_decrypt(&walk, req, false);
440         crypto_aegis128_init(&state, &ctx->key, req->iv);
441         crypto_aegis128_process_ad(&state, req->src, req->assoclen, false);
442         crypto_aegis128_process_crypt(&state, &walk,
443                                       crypto_aegis128_decrypt_chunk);
444         crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen);
445
446         if (unlikely(crypto_memneq(tag.bytes, zeros, authsize))) {
447                 /*
448                  * From Chapter 4. 'Security Analysis' of the AEGIS spec [0]
449                  *
450                  * "3. If verification fails, the decrypted plaintext and the
451                  *     wrong authentication tag should not be given as output."
452                  *
453                  * [0] https://competitions.cr.yp.to/round3/aegisv11.pdf
454                  */
455                 skcipher_walk_aead_decrypt(&walk, req, false);
456                 crypto_aegis128_process_crypt(NULL, &walk,
457                                               crypto_aegis128_wipe_chunk);
458                 memzero_explicit(&tag, sizeof(tag));
459                 return -EBADMSG;
460         }
461         return 0;
462 }
463
464 static int crypto_aegis128_encrypt_simd(struct aead_request *req)
465 {
466         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
467         union aegis_block tag = {};
468         unsigned int authsize = crypto_aead_authsize(tfm);
469         struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
470         unsigned int cryptlen = req->cryptlen;
471         struct skcipher_walk walk;
472         struct aegis_state state;
473
474         if (!aegis128_do_simd())
475                 return crypto_aegis128_encrypt_generic(req);
476
477         skcipher_walk_aead_encrypt(&walk, req, false);
478         crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
479         crypto_aegis128_process_ad(&state, req->src, req->assoclen, true);
480         crypto_aegis128_process_crypt(&state, &walk,
481                                       crypto_aegis128_encrypt_chunk_simd);
482         crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen, 0);
483
484         scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen,
485                                  authsize, 1);
486         return 0;
487 }
488
489 static int crypto_aegis128_decrypt_simd(struct aead_request *req)
490 {
491         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
492         union aegis_block tag;
493         unsigned int authsize = crypto_aead_authsize(tfm);
494         unsigned int cryptlen = req->cryptlen - authsize;
495         struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
496         struct skcipher_walk walk;
497         struct aegis_state state;
498
499         if (!aegis128_do_simd())
500                 return crypto_aegis128_decrypt_generic(req);
501
502         scatterwalk_map_and_copy(tag.bytes, req->src, req->assoclen + cryptlen,
503                                  authsize, 0);
504
505         skcipher_walk_aead_decrypt(&walk, req, false);
506         crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
507         crypto_aegis128_process_ad(&state, req->src, req->assoclen, true);
508         crypto_aegis128_process_crypt(&state, &walk,
509                                       crypto_aegis128_decrypt_chunk_simd);
510
511         if (unlikely(crypto_aegis128_final_simd(&state, &tag, req->assoclen,
512                                                 cryptlen, authsize))) {
513                 skcipher_walk_aead_decrypt(&walk, req, false);
514                 crypto_aegis128_process_crypt(NULL, &walk,
515                                               crypto_aegis128_wipe_chunk);
516                 return -EBADMSG;
517         }
518         return 0;
519 }
520
521 static struct aead_alg crypto_aegis128_alg_generic = {
522         .setkey                 = crypto_aegis128_setkey,
523         .setauthsize            = crypto_aegis128_setauthsize,
524         .encrypt                = crypto_aegis128_encrypt_generic,
525         .decrypt                = crypto_aegis128_decrypt_generic,
526
527         .ivsize                 = AEGIS128_NONCE_SIZE,
528         .maxauthsize            = AEGIS128_MAX_AUTH_SIZE,
529         .chunksize              = AEGIS_BLOCK_SIZE,
530
531         .base.cra_blocksize     = 1,
532         .base.cra_ctxsize       = sizeof(struct aegis_ctx),
533         .base.cra_alignmask     = 0,
534         .base.cra_priority      = 100,
535         .base.cra_name          = "aegis128",
536         .base.cra_driver_name   = "aegis128-generic",
537         .base.cra_module        = THIS_MODULE,
538 };
539
540 static struct aead_alg crypto_aegis128_alg_simd = {
541         .setkey                 = crypto_aegis128_setkey,
542         .setauthsize            = crypto_aegis128_setauthsize,
543         .encrypt                = crypto_aegis128_encrypt_simd,
544         .decrypt                = crypto_aegis128_decrypt_simd,
545
546         .ivsize                 = AEGIS128_NONCE_SIZE,
547         .maxauthsize            = AEGIS128_MAX_AUTH_SIZE,
548         .chunksize              = AEGIS_BLOCK_SIZE,
549
550         .base.cra_blocksize     = 1,
551         .base.cra_ctxsize       = sizeof(struct aegis_ctx),
552         .base.cra_alignmask     = 0,
553         .base.cra_priority      = 200,
554         .base.cra_name          = "aegis128",
555         .base.cra_driver_name   = "aegis128-simd",
556         .base.cra_module        = THIS_MODULE,
557 };
558
559 static int __init crypto_aegis128_module_init(void)
560 {
561         int ret;
562
563         ret = crypto_register_aead(&crypto_aegis128_alg_generic);
564         if (ret)
565                 return ret;
566
567         if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) &&
568             crypto_aegis128_have_simd()) {
569                 ret = crypto_register_aead(&crypto_aegis128_alg_simd);
570                 if (ret) {
571                         crypto_unregister_aead(&crypto_aegis128_alg_generic);
572                         return ret;
573                 }
574                 static_branch_enable(&have_simd);
575         }
576         return 0;
577 }
578
579 static void __exit crypto_aegis128_module_exit(void)
580 {
581         if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) &&
582             crypto_aegis128_have_simd())
583                 crypto_unregister_aead(&crypto_aegis128_alg_simd);
584
585         crypto_unregister_aead(&crypto_aegis128_alg_generic);
586 }
587
588 subsys_initcall(crypto_aegis128_module_init);
589 module_exit(crypto_aegis128_module_exit);
590
591 MODULE_LICENSE("GPL");
592 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
593 MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm");
594 MODULE_ALIAS_CRYPTO("aegis128");
595 MODULE_ALIAS_CRYPTO("aegis128-generic");
596 MODULE_ALIAS_CRYPTO("aegis128-simd");