1 /*
2 * The MORUS-640 Authenticated-Encryption Algorithm
3 *
4 * Copyright (c) 2016-2018 Ondrej Mosnacek <omosnacek@gmail.com>
5 * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 */
12
13 #include <asm/unaligned.h>
14 #include <crypto/algapi.h>
15 #include <crypto/internal/aead.h>
16 #include <crypto/internal/skcipher.h>
17 #include <crypto/morus_common.h>
18 #include <crypto/scatterwalk.h>
19 #include <linux/err.h>
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/scatterlist.h>
24
25 #define MORUS640_WORD_SIZE 4
26 #define MORUS640_BLOCK_SIZE (MORUS_BLOCK_WORDS * MORUS640_WORD_SIZE)
27 #define MORUS640_BLOCK_ALIGN (__alignof__(__le32))
28 #define MORUS640_ALIGNED(p) IS_ALIGNED((uintptr_t)p, MORUS640_BLOCK_ALIGN)
29
30 struct morus640_block {
31 u32 words[MORUS_BLOCK_WORDS];
32 };
33
34 union morus640_block_in {
35 __le32 words[MORUS_BLOCK_WORDS];
36 u8 bytes[MORUS640_BLOCK_SIZE];
37 };
38
39 struct morus640_state {
40 struct morus640_block s[MORUS_STATE_BLOCKS];
41 };
42
43 struct morus640_ctx {
44 struct morus640_block key;
45 };
46
47 struct morus640_ops {
48 int (*skcipher_walk_init)(struct skcipher_walk *walk,
49 struct aead_request *req, bool atomic);
50
51 void (*crypt_chunk)(struct morus640_state *state,
52 u8 *dst, const u8 *src, unsigned int size);
53 };
54
55 static const struct morus640_block crypto_morus640_const[2] = {
56 { .words = {
57 U32_C(0x02010100),
58 U32_C(0x0d080503),
59 U32_C(0x59372215),
60 U32_C(0x6279e990),
61 } },
62 { .words = {
63 U32_C(0x55183ddb),
64 U32_C(0xf12fc26d),
65 U32_C(0x42311120),
66 U32_C(0xdd28b573),
67 } },
68 };
69
crypto_morus640_round(struct morus640_block * b0,struct morus640_block * b1,struct morus640_block * b2,struct morus640_block * b3,struct morus640_block * b4,const struct morus640_block * m,unsigned int b,unsigned int w)70 static void crypto_morus640_round(struct morus640_block *b0,
71 struct morus640_block *b1,
72 struct morus640_block *b2,
73 struct morus640_block *b3,
74 struct morus640_block *b4,
75 const struct morus640_block *m,
76 unsigned int b, unsigned int w)
77 {
78 unsigned int i;
79 struct morus640_block tmp;
80
81 for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
82 b0->words[i] ^= b1->words[i] & b2->words[i];
83 b0->words[i] ^= b3->words[i];
84 b0->words[i] ^= m->words[i];
85 b0->words[i] = rol32(b0->words[i], b);
86 }
87
88 tmp = *b3;
89 for (i = 0; i < MORUS_BLOCK_WORDS; i++)
90 b3->words[(i + w) % MORUS_BLOCK_WORDS] = tmp.words[i];
91 }
92
crypto_morus640_update(struct morus640_state * state,const struct morus640_block * m)93 static void crypto_morus640_update(struct morus640_state *state,
94 const struct morus640_block *m)
95 {
96 static const struct morus640_block z = {};
97
98 struct morus640_block *s = state->s;
99
100 crypto_morus640_round(&s[0], &s[1], &s[2], &s[3], &s[4], &z, 5, 1);
101 crypto_morus640_round(&s[1], &s[2], &s[3], &s[4], &s[0], m, 31, 2);
102 crypto_morus640_round(&s[2], &s[3], &s[4], &s[0], &s[1], m, 7, 3);
103 crypto_morus640_round(&s[3], &s[4], &s[0], &s[1], &s[2], m, 22, 2);
104 crypto_morus640_round(&s[4], &s[0], &s[1], &s[2], &s[3], m, 13, 1);
105 }
106
crypto_morus640_load_a(struct morus640_block * dst,const u8 * src)107 static void crypto_morus640_load_a(struct morus640_block *dst, const u8 *src)
108 {
109 unsigned int i;
110 for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
111 dst->words[i] = le32_to_cpu(*(const __le32 *)src);
112 src += MORUS640_WORD_SIZE;
113 }
114 }
115
crypto_morus640_load_u(struct morus640_block * dst,const u8 * src)116 static void crypto_morus640_load_u(struct morus640_block *dst, const u8 *src)
117 {
118 unsigned int i;
119 for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
120 dst->words[i] = get_unaligned_le32(src);
121 src += MORUS640_WORD_SIZE;
122 }
123 }
124
crypto_morus640_load(struct morus640_block * dst,const u8 * src)125 static void crypto_morus640_load(struct morus640_block *dst, const u8 *src)
126 {
127 if (MORUS640_ALIGNED(src))
128 crypto_morus640_load_a(dst, src);
129 else
130 crypto_morus640_load_u(dst, src);
131 }
132
crypto_morus640_store_a(u8 * dst,const struct morus640_block * src)133 static void crypto_morus640_store_a(u8 *dst, const struct morus640_block *src)
134 {
135 unsigned int i;
136 for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
137 *(__le32 *)dst = cpu_to_le32(src->words[i]);
138 dst += MORUS640_WORD_SIZE;
139 }
140 }
141
crypto_morus640_store_u(u8 * dst,const struct morus640_block * src)142 static void crypto_morus640_store_u(u8 *dst, const struct morus640_block *src)
143 {
144 unsigned int i;
145 for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
146 put_unaligned_le32(src->words[i], dst);
147 dst += MORUS640_WORD_SIZE;
148 }
149 }
150
crypto_morus640_store(u8 * dst,const struct morus640_block * src)151 static void crypto_morus640_store(u8 *dst, const struct morus640_block *src)
152 {
153 if (MORUS640_ALIGNED(dst))
154 crypto_morus640_store_a(dst, src);
155 else
156 crypto_morus640_store_u(dst, src);
157 }
158
crypto_morus640_ad(struct morus640_state * state,const u8 * src,unsigned int size)159 static void crypto_morus640_ad(struct morus640_state *state, const u8 *src,
160 unsigned int size)
161 {
162 struct morus640_block m;
163
164 if (MORUS640_ALIGNED(src)) {
165 while (size >= MORUS640_BLOCK_SIZE) {
166 crypto_morus640_load_a(&m, src);
167 crypto_morus640_update(state, &m);
168
169 size -= MORUS640_BLOCK_SIZE;
170 src += MORUS640_BLOCK_SIZE;
171 }
172 } else {
173 while (size >= MORUS640_BLOCK_SIZE) {
174 crypto_morus640_load_u(&m, src);
175 crypto_morus640_update(state, &m);
176
177 size -= MORUS640_BLOCK_SIZE;
178 src += MORUS640_BLOCK_SIZE;
179 }
180 }
181 }
182
crypto_morus640_core(const struct morus640_state * state,struct morus640_block * blk)183 static void crypto_morus640_core(const struct morus640_state *state,
184 struct morus640_block *blk)
185 {
186 unsigned int i;
187
188 for (i = 0; i < MORUS_BLOCK_WORDS; i++)
189 blk->words[(i + 3) % MORUS_BLOCK_WORDS] ^= state->s[1].words[i];
190
191 for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
192 blk->words[i] ^= state->s[0].words[i];
193 blk->words[i] ^= state->s[2].words[i] & state->s[3].words[i];
194 }
195 }
196
crypto_morus640_encrypt_chunk(struct morus640_state * state,u8 * dst,const u8 * src,unsigned int size)197 static void crypto_morus640_encrypt_chunk(struct morus640_state *state, u8 *dst,
198 const u8 *src, unsigned int size)
199 {
200 struct morus640_block c, m;
201
202 if (MORUS640_ALIGNED(src) && MORUS640_ALIGNED(dst)) {
203 while (size >= MORUS640_BLOCK_SIZE) {
204 crypto_morus640_load_a(&m, src);
205 c = m;
206 crypto_morus640_core(state, &c);
207 crypto_morus640_store_a(dst, &c);
208 crypto_morus640_update(state, &m);
209
210 src += MORUS640_BLOCK_SIZE;
211 dst += MORUS640_BLOCK_SIZE;
212 size -= MORUS640_BLOCK_SIZE;
213 }
214 } else {
215 while (size >= MORUS640_BLOCK_SIZE) {
216 crypto_morus640_load_u(&m, src);
217 c = m;
218 crypto_morus640_core(state, &c);
219 crypto_morus640_store_u(dst, &c);
220 crypto_morus640_update(state, &m);
221
222 src += MORUS640_BLOCK_SIZE;
223 dst += MORUS640_BLOCK_SIZE;
224 size -= MORUS640_BLOCK_SIZE;
225 }
226 }
227
228 if (size > 0) {
229 union morus640_block_in tail;
230
231 memcpy(tail.bytes, src, size);
232 memset(tail.bytes + size, 0, MORUS640_BLOCK_SIZE - size);
233
234 crypto_morus640_load_a(&m, tail.bytes);
235 c = m;
236 crypto_morus640_core(state, &c);
237 crypto_morus640_store_a(tail.bytes, &c);
238 crypto_morus640_update(state, &m);
239
240 memcpy(dst, tail.bytes, size);
241 }
242 }
243
crypto_morus640_decrypt_chunk(struct morus640_state * state,u8 * dst,const u8 * src,unsigned int size)244 static void crypto_morus640_decrypt_chunk(struct morus640_state *state, u8 *dst,
245 const u8 *src, unsigned int size)
246 {
247 struct morus640_block m;
248
249 if (MORUS640_ALIGNED(src) && MORUS640_ALIGNED(dst)) {
250 while (size >= MORUS640_BLOCK_SIZE) {
251 crypto_morus640_load_a(&m, src);
252 crypto_morus640_core(state, &m);
253 crypto_morus640_store_a(dst, &m);
254 crypto_morus640_update(state, &m);
255
256 src += MORUS640_BLOCK_SIZE;
257 dst += MORUS640_BLOCK_SIZE;
258 size -= MORUS640_BLOCK_SIZE;
259 }
260 } else {
261 while (size >= MORUS640_BLOCK_SIZE) {
262 crypto_morus640_load_u(&m, src);
263 crypto_morus640_core(state, &m);
264 crypto_morus640_store_u(dst, &m);
265 crypto_morus640_update(state, &m);
266
267 src += MORUS640_BLOCK_SIZE;
268 dst += MORUS640_BLOCK_SIZE;
269 size -= MORUS640_BLOCK_SIZE;
270 }
271 }
272
273 if (size > 0) {
274 union morus640_block_in tail;
275
276 memcpy(tail.bytes, src, size);
277 memset(tail.bytes + size, 0, MORUS640_BLOCK_SIZE - size);
278
279 crypto_morus640_load_a(&m, tail.bytes);
280 crypto_morus640_core(state, &m);
281 crypto_morus640_store_a(tail.bytes, &m);
282 memset(tail.bytes + size, 0, MORUS640_BLOCK_SIZE - size);
283 crypto_morus640_load_a(&m, tail.bytes);
284 crypto_morus640_update(state, &m);
285
286 memcpy(dst, tail.bytes, size);
287 }
288 }
289
crypto_morus640_init(struct morus640_state * state,const struct morus640_block * key,const u8 * iv)290 static void crypto_morus640_init(struct morus640_state *state,
291 const struct morus640_block *key,
292 const u8 *iv)
293 {
294 static const struct morus640_block z = {};
295
296 unsigned int i;
297
298 crypto_morus640_load(&state->s[0], iv);
299 state->s[1] = *key;
300 for (i = 0; i < MORUS_BLOCK_WORDS; i++)
301 state->s[2].words[i] = U32_C(0xFFFFFFFF);
302 state->s[3] = crypto_morus640_const[0];
303 state->s[4] = crypto_morus640_const[1];
304
305 for (i = 0; i < 16; i++)
306 crypto_morus640_update(state, &z);
307
308 for (i = 0; i < MORUS_BLOCK_WORDS; i++)
309 state->s[1].words[i] ^= key->words[i];
310 }
311
crypto_morus640_process_ad(struct morus640_state * state,struct scatterlist * sg_src,unsigned int assoclen)312 static void crypto_morus640_process_ad(struct morus640_state *state,
313 struct scatterlist *sg_src,
314 unsigned int assoclen)
315 {
316 struct scatter_walk walk;
317 struct morus640_block m;
318 union morus640_block_in buf;
319 unsigned int pos = 0;
320
321 scatterwalk_start(&walk, sg_src);
322 while (assoclen != 0) {
323 unsigned int size = scatterwalk_clamp(&walk, assoclen);
324 unsigned int left = size;
325 void *mapped = scatterwalk_map(&walk);
326 const u8 *src = (const u8 *)mapped;
327
328 if (pos + size >= MORUS640_BLOCK_SIZE) {
329 if (pos > 0) {
330 unsigned int fill = MORUS640_BLOCK_SIZE - pos;
331 memcpy(buf.bytes + pos, src, fill);
332
333 crypto_morus640_load_a(&m, buf.bytes);
334 crypto_morus640_update(state, &m);
335
336 pos = 0;
337 left -= fill;
338 src += fill;
339 }
340
341 crypto_morus640_ad(state, src, left);
342 src += left & ~(MORUS640_BLOCK_SIZE - 1);
343 left &= MORUS640_BLOCK_SIZE - 1;
344 }
345
346 memcpy(buf.bytes + pos, src, left);
347
348 pos += left;
349 assoclen -= size;
350 scatterwalk_unmap(mapped);
351 scatterwalk_advance(&walk, size);
352 scatterwalk_done(&walk, 0, assoclen);
353 }
354
355 if (pos > 0) {
356 memset(buf.bytes + pos, 0, MORUS640_BLOCK_SIZE - pos);
357
358 crypto_morus640_load_a(&m, buf.bytes);
359 crypto_morus640_update(state, &m);
360 }
361 }
362
crypto_morus640_process_crypt(struct morus640_state * state,struct aead_request * req,const struct morus640_ops * ops)363 static void crypto_morus640_process_crypt(struct morus640_state *state,
364 struct aead_request *req,
365 const struct morus640_ops *ops)
366 {
367 struct skcipher_walk walk;
368 u8 *dst;
369 const u8 *src;
370
371 ops->skcipher_walk_init(&walk, req, false);
372
373 while (walk.nbytes) {
374 src = walk.src.virt.addr;
375 dst = walk.dst.virt.addr;
376
377 ops->crypt_chunk(state, dst, src, walk.nbytes);
378
379 skcipher_walk_done(&walk, 0);
380 }
381 }
382
crypto_morus640_final(struct morus640_state * state,struct morus640_block * tag_xor,u64 assoclen,u64 cryptlen)383 static void crypto_morus640_final(struct morus640_state *state,
384 struct morus640_block *tag_xor,
385 u64 assoclen, u64 cryptlen)
386 {
387 u64 assocbits = assoclen * 8;
388 u64 cryptbits = cryptlen * 8;
389
390 u32 assocbits_lo = (u32)assocbits;
391 u32 assocbits_hi = (u32)(assocbits >> 32);
392 u32 cryptbits_lo = (u32)cryptbits;
393 u32 cryptbits_hi = (u32)(cryptbits >> 32);
394
395 struct morus640_block tmp;
396 unsigned int i;
397
398 tmp.words[0] = cpu_to_le32(assocbits_lo);
399 tmp.words[1] = cpu_to_le32(assocbits_hi);
400 tmp.words[2] = cpu_to_le32(cryptbits_lo);
401 tmp.words[3] = cpu_to_le32(cryptbits_hi);
402
403 for (i = 0; i < MORUS_BLOCK_WORDS; i++)
404 state->s[4].words[i] ^= state->s[0].words[i];
405
406 for (i = 0; i < 10; i++)
407 crypto_morus640_update(state, &tmp);
408
409 crypto_morus640_core(state, tag_xor);
410 }
411
crypto_morus640_setkey(struct crypto_aead * aead,const u8 * key,unsigned int keylen)412 static int crypto_morus640_setkey(struct crypto_aead *aead, const u8 *key,
413 unsigned int keylen)
414 {
415 struct morus640_ctx *ctx = crypto_aead_ctx(aead);
416
417 if (keylen != MORUS640_BLOCK_SIZE) {
418 crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
419 return -EINVAL;
420 }
421
422 crypto_morus640_load(&ctx->key, key);
423 return 0;
424 }
425
crypto_morus640_setauthsize(struct crypto_aead * tfm,unsigned int authsize)426 static int crypto_morus640_setauthsize(struct crypto_aead *tfm,
427 unsigned int authsize)
428 {
429 return (authsize <= MORUS_MAX_AUTH_SIZE) ? 0 : -EINVAL;
430 }
431
crypto_morus640_crypt(struct aead_request * req,struct morus640_block * tag_xor,unsigned int cryptlen,const struct morus640_ops * ops)432 static void crypto_morus640_crypt(struct aead_request *req,
433 struct morus640_block *tag_xor,
434 unsigned int cryptlen,
435 const struct morus640_ops *ops)
436 {
437 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
438 struct morus640_ctx *ctx = crypto_aead_ctx(tfm);
439 struct morus640_state state;
440
441 crypto_morus640_init(&state, &ctx->key, req->iv);
442 crypto_morus640_process_ad(&state, req->src, req->assoclen);
443 crypto_morus640_process_crypt(&state, req, ops);
444 crypto_morus640_final(&state, tag_xor, req->assoclen, cryptlen);
445 }
446
crypto_morus640_encrypt(struct aead_request * req)447 static int crypto_morus640_encrypt(struct aead_request *req)
448 {
449 static const struct morus640_ops ops = {
450 .skcipher_walk_init = skcipher_walk_aead_encrypt,
451 .crypt_chunk = crypto_morus640_encrypt_chunk,
452 };
453
454 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
455 struct morus640_block tag = {};
456 union morus640_block_in tag_out;
457 unsigned int authsize = crypto_aead_authsize(tfm);
458 unsigned int cryptlen = req->cryptlen;
459
460 crypto_morus640_crypt(req, &tag, cryptlen, &ops);
461 crypto_morus640_store(tag_out.bytes, &tag);
462
463 scatterwalk_map_and_copy(tag_out.bytes, req->dst,
464 req->assoclen + cryptlen, authsize, 1);
465 return 0;
466 }
467
crypto_morus640_decrypt(struct aead_request * req)468 static int crypto_morus640_decrypt(struct aead_request *req)
469 {
470 static const struct morus640_ops ops = {
471 .skcipher_walk_init = skcipher_walk_aead_decrypt,
472 .crypt_chunk = crypto_morus640_decrypt_chunk,
473 };
474 static const u8 zeros[MORUS640_BLOCK_SIZE] = {};
475
476 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
477 union morus640_block_in tag_in;
478 struct morus640_block tag;
479 unsigned int authsize = crypto_aead_authsize(tfm);
480 unsigned int cryptlen = req->cryptlen - authsize;
481
482 scatterwalk_map_and_copy(tag_in.bytes, req->src,
483 req->assoclen + cryptlen, authsize, 0);
484
485 crypto_morus640_load(&tag, tag_in.bytes);
486 crypto_morus640_crypt(req, &tag, cryptlen, &ops);
487 crypto_morus640_store(tag_in.bytes, &tag);
488
489 return crypto_memneq(tag_in.bytes, zeros, authsize) ? -EBADMSG : 0;
490 }
491
crypto_morus640_init_tfm(struct crypto_aead * tfm)492 static int crypto_morus640_init_tfm(struct crypto_aead *tfm)
493 {
494 return 0;
495 }
496
crypto_morus640_exit_tfm(struct crypto_aead * tfm)497 static void crypto_morus640_exit_tfm(struct crypto_aead *tfm)
498 {
499 }
500
501 static struct aead_alg crypto_morus640_alg = {
502 .setkey = crypto_morus640_setkey,
503 .setauthsize = crypto_morus640_setauthsize,
504 .encrypt = crypto_morus640_encrypt,
505 .decrypt = crypto_morus640_decrypt,
506 .init = crypto_morus640_init_tfm,
507 .exit = crypto_morus640_exit_tfm,
508
509 .ivsize = MORUS_NONCE_SIZE,
510 .maxauthsize = MORUS_MAX_AUTH_SIZE,
511 .chunksize = MORUS640_BLOCK_SIZE,
512
513 .base = {
514 .cra_blocksize = 1,
515 .cra_ctxsize = sizeof(struct morus640_ctx),
516 .cra_alignmask = 0,
517
518 .cra_priority = 100,
519
520 .cra_name = "morus640",
521 .cra_driver_name = "morus640-generic",
522
523 .cra_module = THIS_MODULE,
524 }
525 };
526
crypto_morus640_module_init(void)527 static int __init crypto_morus640_module_init(void)
528 {
529 return crypto_register_aead(&crypto_morus640_alg);
530 }
531
crypto_morus640_module_exit(void)532 static void __exit crypto_morus640_module_exit(void)
533 {
534 crypto_unregister_aead(&crypto_morus640_alg);
535 }
536
537 module_init(crypto_morus640_module_init);
538 module_exit(crypto_morus640_module_exit);
539
540 MODULE_LICENSE("GPL");
541 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
542 MODULE_DESCRIPTION("MORUS-640 AEAD algorithm");
543 MODULE_ALIAS_CRYPTO("morus640");
544 MODULE_ALIAS_CRYPTO("morus640-generic");
545
