crypto/morus640.c

   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
  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
  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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 383 static void crypto_morus640_final(struct morus640_state *state,
 384                                   struct morus640_block *tag_xor,
 385                                   u64 assoclen, u64 cryptlen)
 386 {
 387         struct morus640_block tmp;
 388         unsigned int i;
 389
 390         tmp.words[0] = lower_32_bits(assoclen * 8);
 391         tmp.words[1] = upper_32_bits(assoclen * 8);
 392         tmp.words[2] = lower_32_bits(cryptlen * 8);
 393         tmp.words[3] = upper_32_bits(cryptlen * 8);
 394
 395         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 396                 state->s[4].words[i] ^= state->s[0].words[i];
 397
 398         for (i = 0; i < 10; i++)
 399                 crypto_morus640_update(state, &tmp);
 400
 401         crypto_morus640_core(state, tag_xor);
 402 }
 403
 404 static int crypto_morus640_setkey(struct crypto_aead *aead, const u8 *key,
 405                                   unsigned int keylen)
 406 {
 407         struct morus640_ctx *ctx = crypto_aead_ctx(aead);
 408
 409         if (keylen != MORUS640_BLOCK_SIZE) {
 410                 crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
 411                 return -EINVAL;
 412         }
 413
 414         crypto_morus640_load(&ctx->key, key);
 415         return 0;
 416 }
 417
 418 static int crypto_morus640_setauthsize(struct crypto_aead *tfm,
 419                                        unsigned int authsize)
 420 {
 421         return (authsize <= MORUS_MAX_AUTH_SIZE) ? 0 : -EINVAL;
 422 }
 423
 424 static void crypto_morus640_crypt(struct aead_request *req,
 425                                   struct morus640_block *tag_xor,
 426                                   unsigned int cryptlen,
 427                                   const struct morus640_ops *ops)
 428 {
 429         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 430         struct morus640_ctx *ctx = crypto_aead_ctx(tfm);
 431         struct morus640_state state;
 432
 433         crypto_morus640_init(&state, &ctx->key, req->iv);
 434         crypto_morus640_process_ad(&state, req->src, req->assoclen);
 435         crypto_morus640_process_crypt(&state, req, ops);
 436         crypto_morus640_final(&state, tag_xor, req->assoclen, cryptlen);
 437 }
 438
 439 static int crypto_morus640_encrypt(struct aead_request *req)
 440 {
 441         static const struct morus640_ops ops = {
 442                 .skcipher_walk_init = skcipher_walk_aead_encrypt,
 443                 .crypt_chunk = crypto_morus640_encrypt_chunk,
 444         };
 445
 446         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 447         struct morus640_block tag = {};
 448         union morus640_block_in tag_out;
 449         unsigned int authsize = crypto_aead_authsize(tfm);
 450         unsigned int cryptlen = req->cryptlen;
 451
 452         crypto_morus640_crypt(req, &tag, cryptlen, &ops);
 453         crypto_morus640_store(tag_out.bytes, &tag);
 454
 455         scatterwalk_map_and_copy(tag_out.bytes, req->dst,
 456                                  req->assoclen + cryptlen, authsize, 1);
 457         return 0;
 458 }
 459
 460 static int crypto_morus640_decrypt(struct aead_request *req)
 461 {
 462         static const struct morus640_ops ops = {
 463                 .skcipher_walk_init = skcipher_walk_aead_decrypt,
 464                 .crypt_chunk = crypto_morus640_decrypt_chunk,
 465         };
 466         static const u8 zeros[MORUS640_BLOCK_SIZE] = {};
 467
 468         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 469         union morus640_block_in tag_in;
 470         struct morus640_block tag;
 471         unsigned int authsize = crypto_aead_authsize(tfm);
 472         unsigned int cryptlen = req->cryptlen - authsize;
 473
 474         scatterwalk_map_and_copy(tag_in.bytes, req->src,
 475                                  req->assoclen + cryptlen, authsize, 0);
 476
 477         crypto_morus640_load(&tag, tag_in.bytes);
 478         crypto_morus640_crypt(req, &tag, cryptlen, &ops);
 479         crypto_morus640_store(tag_in.bytes, &tag);
 480
 481         return crypto_memneq(tag_in.bytes, zeros, authsize) ? -EBADMSG : 0;
 482 }
 483
 484 static int crypto_morus640_init_tfm(struct crypto_aead *tfm)
 485 {
 486         return 0;
 487 }
 488
 489 static void crypto_morus640_exit_tfm(struct crypto_aead *tfm)
 490 {
 491 }
 492
 493 static struct aead_alg crypto_morus640_alg = {
 494         .setkey = crypto_morus640_setkey,
 495         .setauthsize = crypto_morus640_setauthsize,
 496         .encrypt = crypto_morus640_encrypt,
 497         .decrypt = crypto_morus640_decrypt,
 498         .init = crypto_morus640_init_tfm,
 499         .exit = crypto_morus640_exit_tfm,
 500
 501         .ivsize = MORUS_NONCE_SIZE,
 502         .maxauthsize = MORUS_MAX_AUTH_SIZE,
 503         .chunksize = MORUS640_BLOCK_SIZE,
 504
 505         .base = {
 506                 .cra_blocksize = 1,
 507                 .cra_ctxsize = sizeof(struct morus640_ctx),
 508                 .cra_alignmask = 0,
 509
 510                 .cra_priority = 100,
 511
 512                 .cra_name = "morus640",
 513                 .cra_driver_name = "morus640-generic",
 514
 515                 .cra_module = THIS_MODULE,
 516         }
 517 };
 518
 519 static int __init crypto_morus640_module_init(void)
 520 {
 521         return crypto_register_aead(&crypto_morus640_alg);
 522 }
 523
 524 static void __exit crypto_morus640_module_exit(void)
 525 {
 526         crypto_unregister_aead(&crypto_morus640_alg);
 527 }
 528
 529 module_init(crypto_morus640_module_init);
 530 module_exit(crypto_morus640_module_exit);
 531
 532 MODULE_LICENSE("GPL");
 533 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
 534 MODULE_DESCRIPTION("MORUS-640 AEAD algorithm");
 535 MODULE_ALIAS_CRYPTO("morus640");
 536 MODULE_ALIAS_CRYPTO("morus640-generic");