crypto/morus1280.c

   1 /*
   2  * The MORUS-1280 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 MORUS1280_WORD_SIZE 8
  26 #define MORUS1280_BLOCK_SIZE (MORUS_BLOCK_WORDS * MORUS1280_WORD_SIZE)
  27 #define MORUS1280_BLOCK_ALIGN (__alignof__(__le64))
  28 #define MORUS1280_ALIGNED(p) IS_ALIGNED((uintptr_t)p, MORUS1280_BLOCK_ALIGN)
  29
  30 struct morus1280_block {
  31         u64 words[MORUS_BLOCK_WORDS];
  32 };
  33
  34 union morus1280_block_in {
  35         __le64 words[MORUS_BLOCK_WORDS];
  36         u8 bytes[MORUS1280_BLOCK_SIZE];
  37 };
  38
  39 struct morus1280_state {
  40         struct morus1280_block s[MORUS_STATE_BLOCKS];
  41 };
  42
  43 struct morus1280_ctx {
  44         struct morus1280_block key;
  45 };
  46
  47 struct morus1280_ops {
  48         int (*skcipher_walk_init)(struct skcipher_walk *walk,
  49                                   struct aead_request *req, bool atomic);
  50
  51         void (*crypt_chunk)(struct morus1280_state *state,
  52                             u8 *dst, const u8 *src, unsigned int size);
  53 };
  54
  55 static const struct morus1280_block crypto_morus1280_const[1] = {
  56         { .words = {
  57                 U64_C(0x0d08050302010100),
  58                 U64_C(0x6279e99059372215),
  59                 U64_C(0xf12fc26d55183ddb),
  60                 U64_C(0xdd28b57342311120),
  61         } },
  62 };
  63
  64 static void crypto_morus1280_round(struct morus1280_block *b0,
  65                                    struct morus1280_block *b1,
  66                                    struct morus1280_block *b2,
  67                                    struct morus1280_block *b3,
  68                                    struct morus1280_block *b4,
  69                                    const struct morus1280_block *m,
  70                                    unsigned int b, unsigned int w)
  71 {
  72         unsigned int i;
  73         struct morus1280_block tmp;
  74
  75         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
  76                 b0->words[i] ^= b1->words[i] & b2->words[i];
  77                 b0->words[i] ^= b3->words[i];
  78                 b0->words[i] ^= m->words[i];
  79                 b0->words[i] = rol64(b0->words[i], b);
  80         }
  81
  82         tmp = *b3;
  83         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
  84                 b3->words[(i + w) % MORUS_BLOCK_WORDS] = tmp.words[i];
  85 }
  86
  87 static void crypto_morus1280_update(struct morus1280_state *state,
  88                                     const struct morus1280_block *m)
  89 {
  90         static const struct morus1280_block z = {};
  91
  92         struct morus1280_block *s = state->s;
  93
  94         crypto_morus1280_round(&s[0], &s[1], &s[2], &s[3], &s[4], &z, 13, 1);
  95         crypto_morus1280_round(&s[1], &s[2], &s[3], &s[4], &s[0], m,  46, 2);
  96         crypto_morus1280_round(&s[2], &s[3], &s[4], &s[0], &s[1], m,  38, 3);
  97         crypto_morus1280_round(&s[3], &s[4], &s[0], &s[1], &s[2], m,   7, 2);
  98         crypto_morus1280_round(&s[4], &s[0], &s[1], &s[2], &s[3], m,   4, 1);
  99 }
 100
 101 static void crypto_morus1280_load_a(struct morus1280_block *dst, const u8 *src)
 102 {
 103         unsigned int i;
 104         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 105                 dst->words[i] = le64_to_cpu(*(const __le64 *)src);
 106                 src += MORUS1280_WORD_SIZE;
 107         }
 108 }
 109
 110 static void crypto_morus1280_load_u(struct morus1280_block *dst, const u8 *src)
 111 {
 112         unsigned int i;
 113         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 114                 dst->words[i] = get_unaligned_le64(src);
 115                 src += MORUS1280_WORD_SIZE;
 116         }
 117 }
 118
 119 static void crypto_morus1280_load(struct morus1280_block *dst, const u8 *src)
 120 {
 121         if (MORUS1280_ALIGNED(src))
 122                 crypto_morus1280_load_a(dst, src);
 123         else
 124                 crypto_morus1280_load_u(dst, src);
 125 }
 126
 127 static void crypto_morus1280_store_a(u8 *dst, const struct morus1280_block *src)
 128 {
 129         unsigned int i;
 130         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 131                 *(__le64 *)dst = cpu_to_le64(src->words[i]);
 132                 dst += MORUS1280_WORD_SIZE;
 133         }
 134 }
 135
 136 static void crypto_morus1280_store_u(u8 *dst, const struct morus1280_block *src)
 137 {
 138         unsigned int i;
 139         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 140                 put_unaligned_le64(src->words[i], dst);
 141                 dst += MORUS1280_WORD_SIZE;
 142         }
 143 }
 144
 145 static void crypto_morus1280_store(u8 *dst, const struct morus1280_block *src)
 146 {
 147         if (MORUS1280_ALIGNED(dst))
 148                 crypto_morus1280_store_a(dst, src);
 149         else
 150                 crypto_morus1280_store_u(dst, src);
 151 }
 152
 153 static void crypto_morus1280_ad(struct morus1280_state *state, const u8 *src,
 154                                 unsigned int size)
 155 {
 156         struct morus1280_block m;
 157
 158         if (MORUS1280_ALIGNED(src)) {
 159                 while (size >= MORUS1280_BLOCK_SIZE) {
 160                         crypto_morus1280_load_a(&m, src);
 161                         crypto_morus1280_update(state, &m);
 162
 163                         size -= MORUS1280_BLOCK_SIZE;
 164                         src += MORUS1280_BLOCK_SIZE;
 165                 }
 166         } else {
 167                 while (size >= MORUS1280_BLOCK_SIZE) {
 168                         crypto_morus1280_load_u(&m, src);
 169                         crypto_morus1280_update(state, &m);
 170
 171                         size -= MORUS1280_BLOCK_SIZE;
 172                         src += MORUS1280_BLOCK_SIZE;
 173                 }
 174         }
 175 }
 176
 177 static void crypto_morus1280_core(const struct morus1280_state *state,
 178                                   struct morus1280_block *blk)
 179 {
 180         unsigned int i;
 181
 182         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 183                 blk->words[(i + 3) % MORUS_BLOCK_WORDS] ^= state->s[1].words[i];
 184
 185         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 186                 blk->words[i] ^= state->s[0].words[i];
 187                 blk->words[i] ^= state->s[2].words[i] & state->s[3].words[i];
 188         }
 189 }
 190
 191 static void crypto_morus1280_encrypt_chunk(struct morus1280_state *state,
 192                                            u8 *dst, const u8 *src,
 193                                            unsigned int size)
 194 {
 195         struct morus1280_block c, m;
 196
 197         if (MORUS1280_ALIGNED(src) && MORUS1280_ALIGNED(dst)) {
 198                 while (size >= MORUS1280_BLOCK_SIZE) {
 199                         crypto_morus1280_load_a(&m, src);
 200                         c = m;
 201                         crypto_morus1280_core(state, &c);
 202                         crypto_morus1280_store_a(dst, &c);
 203                         crypto_morus1280_update(state, &m);
 204
 205                         src += MORUS1280_BLOCK_SIZE;
 206                         dst += MORUS1280_BLOCK_SIZE;
 207                         size -= MORUS1280_BLOCK_SIZE;
 208                 }
 209         } else {
 210                 while (size >= MORUS1280_BLOCK_SIZE) {
 211                         crypto_morus1280_load_u(&m, src);
 212                         c = m;
 213                         crypto_morus1280_core(state, &c);
 214                         crypto_morus1280_store_u(dst, &c);
 215                         crypto_morus1280_update(state, &m);
 216
 217                         src += MORUS1280_BLOCK_SIZE;
 218                         dst += MORUS1280_BLOCK_SIZE;
 219                         size -= MORUS1280_BLOCK_SIZE;
 220                 }
 221         }
 222
 223         if (size > 0) {
 224                 union morus1280_block_in tail;
 225
 226                 memcpy(tail.bytes, src, size);
 227                 memset(tail.bytes + size, 0, MORUS1280_BLOCK_SIZE - size);
 228
 229                 crypto_morus1280_load_a(&m, tail.bytes);
 230                 c = m;
 231                 crypto_morus1280_core(state, &c);
 232                 crypto_morus1280_store_a(tail.bytes, &c);
 233                 crypto_morus1280_update(state, &m);
 234
 235                 memcpy(dst, tail.bytes, size);
 236         }
 237 }
 238
 239 static void crypto_morus1280_decrypt_chunk(struct morus1280_state *state,
 240                                            u8 *dst, const u8 *src,
 241                                            unsigned int size)
 242 {
 243         struct morus1280_block m;
 244
 245         if (MORUS1280_ALIGNED(src) && MORUS1280_ALIGNED(dst)) {
 246                 while (size >= MORUS1280_BLOCK_SIZE) {
 247                         crypto_morus1280_load_a(&m, src);
 248                         crypto_morus1280_core(state, &m);
 249                         crypto_morus1280_store_a(dst, &m);
 250                         crypto_morus1280_update(state, &m);
 251
 252                         src += MORUS1280_BLOCK_SIZE;
 253                         dst += MORUS1280_BLOCK_SIZE;
 254                         size -= MORUS1280_BLOCK_SIZE;
 255                 }
 256         } else {
 257                 while (size >= MORUS1280_BLOCK_SIZE) {
 258                         crypto_morus1280_load_u(&m, src);
 259                         crypto_morus1280_core(state, &m);
 260                         crypto_morus1280_store_u(dst, &m);
 261                         crypto_morus1280_update(state, &m);
 262
 263                         src += MORUS1280_BLOCK_SIZE;
 264                         dst += MORUS1280_BLOCK_SIZE;
 265                         size -= MORUS1280_BLOCK_SIZE;
 266                 }
 267         }
 268
 269         if (size > 0) {
 270                 union morus1280_block_in tail;
 271
 272                 memcpy(tail.bytes, src, size);
 273                 memset(tail.bytes + size, 0, MORUS1280_BLOCK_SIZE - size);
 274
 275                 crypto_morus1280_load_a(&m, tail.bytes);
 276                 crypto_morus1280_core(state, &m);
 277                 crypto_morus1280_store_a(tail.bytes, &m);
 278                 memset(tail.bytes + size, 0, MORUS1280_BLOCK_SIZE - size);
 279                 crypto_morus1280_load_a(&m, tail.bytes);
 280                 crypto_morus1280_update(state, &m);
 281
 282                 memcpy(dst, tail.bytes, size);
 283         }
 284 }
 285
 286 static void crypto_morus1280_init(struct morus1280_state *state,
 287                                   const struct morus1280_block *key,
 288                                   const u8 *iv)
 289 {
 290         static const struct morus1280_block z = {};
 291
 292         union morus1280_block_in tmp;
 293         unsigned int i;
 294
 295         memcpy(tmp.bytes, iv, MORUS_NONCE_SIZE);
 296         memset(tmp.bytes + MORUS_NONCE_SIZE, 0,
 297                MORUS1280_BLOCK_SIZE - MORUS_NONCE_SIZE);
 298
 299         crypto_morus1280_load(&state->s[0], tmp.bytes);
 300         state->s[1] = *key;
 301         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 302                 state->s[2].words[i] = U64_C(0xFFFFFFFFFFFFFFFF);
 303         state->s[3] = z;
 304         state->s[4] = crypto_morus1280_const[0];
 305
 306         for (i = 0; i < 16; i++)
 307                 crypto_morus1280_update(state, &z);
 308
 309         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 310                 state->s[1].words[i] ^= key->words[i];
 311 }
 312
 313 static void crypto_morus1280_process_ad(struct morus1280_state *state,
 314                                         struct scatterlist *sg_src,
 315                                         unsigned int assoclen)
 316 {
 317         struct scatter_walk walk;
 318         struct morus1280_block m;
 319         union morus1280_block_in buf;
 320         unsigned int pos = 0;
 321
 322         scatterwalk_start(&walk, sg_src);
 323         while (assoclen != 0) {
 324                 unsigned int size = scatterwalk_clamp(&walk, assoclen);
 325                 unsigned int left = size;
 326                 void *mapped = scatterwalk_map(&walk);
 327                 const u8 *src = (const u8 *)mapped;
 328
 329                 if (pos + size >= MORUS1280_BLOCK_SIZE) {
 330                         if (pos > 0) {
 331                                 unsigned int fill = MORUS1280_BLOCK_SIZE - pos;
 332                                 memcpy(buf.bytes + pos, src, fill);
 333
 334                                 crypto_morus1280_load_a(&m, buf.bytes);
 335                                 crypto_morus1280_update(state, &m);
 336
 337                                 pos = 0;
 338                                 left -= fill;
 339                                 src += fill;
 340                         }
 341
 342                         crypto_morus1280_ad(state, src, left);
 343                         src += left & ~(MORUS1280_BLOCK_SIZE - 1);
 344                         left &= MORUS1280_BLOCK_SIZE - 1;
 345                 }
 346
 347                 memcpy(buf.bytes + pos, src, left);
 348
 349                 pos += left;
 350                 assoclen -= size;
 351                 scatterwalk_unmap(mapped);
 352                 scatterwalk_advance(&walk, size);
 353                 scatterwalk_done(&walk, 0, assoclen);
 354         }
 355
 356         if (pos > 0) {
 357                 memset(buf.bytes + pos, 0, MORUS1280_BLOCK_SIZE - pos);
 358
 359                 crypto_morus1280_load_a(&m, buf.bytes);
 360                 crypto_morus1280_update(state, &m);
 361         }
 362 }
 363
 364 static void crypto_morus1280_process_crypt(struct morus1280_state *state,
 365                                            struct aead_request *req,
 366                                            const struct morus1280_ops *ops)
 367 {
 368         struct skcipher_walk walk;
 369
 370         ops->skcipher_walk_init(&walk, req, false);
 371
 372         while (walk.nbytes) {
 373                 unsigned int nbytes = walk.nbytes;
 374
 375                 if (nbytes < walk.total)
 376                         nbytes = round_down(nbytes, walk.stride);
 377
 378                 ops->crypt_chunk(state, walk.dst.virt.addr, walk.src.virt.addr,
 379                                  nbytes);
 380
 381                 skcipher_walk_done(&walk, walk.nbytes - nbytes);
 382         }
 383 }
 384
 385 static void crypto_morus1280_final(struct morus1280_state *state,
 386                                    struct morus1280_block *tag_xor,
 387                                    u64 assoclen, u64 cryptlen)
 388 {
 389         struct morus1280_block tmp;
 390         unsigned int i;
 391
 392         tmp.words[0] = assoclen * 8;
 393         tmp.words[1] = cryptlen * 8;
 394         tmp.words[2] = 0;
 395         tmp.words[3] = 0;
 396
 397         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 398                 state->s[4].words[i] ^= state->s[0].words[i];
 399
 400         for (i = 0; i < 10; i++)
 401                 crypto_morus1280_update(state, &tmp);
 402
 403         crypto_morus1280_core(state, tag_xor);
 404 }
 405
 406 static int crypto_morus1280_setkey(struct crypto_aead *aead, const u8 *key,
 407                                    unsigned int keylen)
 408 {
 409         struct morus1280_ctx *ctx = crypto_aead_ctx(aead);
 410         union morus1280_block_in tmp;
 411
 412         if (keylen == MORUS1280_BLOCK_SIZE)
 413                 crypto_morus1280_load(&ctx->key, key);
 414         else if (keylen == MORUS1280_BLOCK_SIZE / 2) {
 415                 memcpy(tmp.bytes, key, keylen);
 416                 memcpy(tmp.bytes + keylen, key, keylen);
 417
 418                 crypto_morus1280_load(&ctx->key, tmp.bytes);
 419         } else {
 420                 crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
 421                 return -EINVAL;
 422         }
 423
 424         return 0;
 425 }
 426
 427 static int crypto_morus1280_setauthsize(struct crypto_aead *tfm,
 428                                         unsigned int authsize)
 429 {
 430         return (authsize <= MORUS_MAX_AUTH_SIZE) ? 0 : -EINVAL;
 431 }
 432
 433 static void crypto_morus1280_crypt(struct aead_request *req,
 434                                    struct morus1280_block *tag_xor,
 435                                    unsigned int cryptlen,
 436                                    const struct morus1280_ops *ops)
 437 {
 438         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 439         struct morus1280_ctx *ctx = crypto_aead_ctx(tfm);
 440         struct morus1280_state state;
 441
 442         crypto_morus1280_init(&state, &ctx->key, req->iv);
 443         crypto_morus1280_process_ad(&state, req->src, req->assoclen);
 444         crypto_morus1280_process_crypt(&state, req, ops);
 445         crypto_morus1280_final(&state, tag_xor, req->assoclen, cryptlen);
 446 }
 447
 448 static int crypto_morus1280_encrypt(struct aead_request *req)
 449 {
 450         static const struct morus1280_ops ops = {
 451                 .skcipher_walk_init = skcipher_walk_aead_encrypt,
 452                 .crypt_chunk = crypto_morus1280_encrypt_chunk,
 453         };
 454
 455         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 456         struct morus1280_block tag = {};
 457         union morus1280_block_in tag_out;
 458         unsigned int authsize = crypto_aead_authsize(tfm);
 459         unsigned int cryptlen = req->cryptlen;
 460
 461         crypto_morus1280_crypt(req, &tag, cryptlen, &ops);
 462         crypto_morus1280_store(tag_out.bytes, &tag);
 463
 464         scatterwalk_map_and_copy(tag_out.bytes, req->dst,
 465                                  req->assoclen + cryptlen, authsize, 1);
 466         return 0;
 467 }
 468
 469 static int crypto_morus1280_decrypt(struct aead_request *req)
 470 {
 471         static const struct morus1280_ops ops = {
 472                 .skcipher_walk_init = skcipher_walk_aead_decrypt,
 473                 .crypt_chunk = crypto_morus1280_decrypt_chunk,
 474         };
 475         static const u8 zeros[MORUS1280_BLOCK_SIZE] = {};
 476
 477         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 478         union morus1280_block_in tag_in;
 479         struct morus1280_block tag;
 480         unsigned int authsize = crypto_aead_authsize(tfm);
 481         unsigned int cryptlen = req->cryptlen - authsize;
 482
 483         scatterwalk_map_and_copy(tag_in.bytes, req->src,
 484                                  req->assoclen + cryptlen, authsize, 0);
 485
 486         crypto_morus1280_load(&tag, tag_in.bytes);
 487         crypto_morus1280_crypt(req, &tag, cryptlen, &ops);
 488         crypto_morus1280_store(tag_in.bytes, &tag);
 489
 490         return crypto_memneq(tag_in.bytes, zeros, authsize) ? -EBADMSG : 0;
 491 }
 492
 493 static int crypto_morus1280_init_tfm(struct crypto_aead *tfm)
 494 {
 495         return 0;
 496 }
 497
 498 static void crypto_morus1280_exit_tfm(struct crypto_aead *tfm)
 499 {
 500 }
 501
 502 static struct aead_alg crypto_morus1280_alg = {
 503         .setkey = crypto_morus1280_setkey,
 504         .setauthsize = crypto_morus1280_setauthsize,
 505         .encrypt = crypto_morus1280_encrypt,
 506         .decrypt = crypto_morus1280_decrypt,
 507         .init = crypto_morus1280_init_tfm,
 508         .exit = crypto_morus1280_exit_tfm,
 509
 510         .ivsize = MORUS_NONCE_SIZE,
 511         .maxauthsize = MORUS_MAX_AUTH_SIZE,
 512         .chunksize = MORUS1280_BLOCK_SIZE,
 513
 514         .base = {
 515                 .cra_blocksize = 1,
 516                 .cra_ctxsize = sizeof(struct morus1280_ctx),
 517                 .cra_alignmask = 0,
 518
 519                 .cra_priority = 100,
 520
 521                 .cra_name = "morus1280",
 522                 .cra_driver_name = "morus1280-generic",
 523
 524                 .cra_module = THIS_MODULE,
 525         }
 526 };
 527
 528
 529 static int __init crypto_morus1280_module_init(void)
 530 {
 531         return crypto_register_aead(&crypto_morus1280_alg);
 532 }
 533
 534 static void __exit crypto_morus1280_module_exit(void)
 535 {
 536         crypto_unregister_aead(&crypto_morus1280_alg);
 537 }
 538
 539 module_init(crypto_morus1280_module_init);
 540 module_exit(crypto_morus1280_module_exit);
 541
 542 MODULE_LICENSE("GPL");
 543 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
 544 MODULE_DESCRIPTION("MORUS-1280 AEAD algorithm");
 545 MODULE_ALIAS_CRYPTO("morus1280");
 546 MODULE_ALIAS_CRYPTO("morus1280-generic");