crypto/morus1280.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * The MORUS-1280 Authenticated-Encryption Algorithm
   4  *
   5  * Copyright (c) 2016-2018 Ondrej Mosnacek <omosnacek@gmail.com>
   6  * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
   7  */
   8
   9 #include <asm/unaligned.h>
  10 #include <crypto/algapi.h>
  11 #include <crypto/internal/aead.h>
  12 #include <crypto/internal/skcipher.h>
  13 #include <crypto/morus_common.h>
  14 #include <crypto/scatterwalk.h>
  15 #include <linux/err.h>
  16 #include <linux/init.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/scatterlist.h>
  20
  21 #define MORUS1280_WORD_SIZE 8
  22 #define MORUS1280_BLOCK_SIZE (MORUS_BLOCK_WORDS * MORUS1280_WORD_SIZE)
  23 #define MORUS1280_BLOCK_ALIGN (__alignof__(__le64))
  24 #define MORUS1280_ALIGNED(p) IS_ALIGNED((uintptr_t)p, MORUS1280_BLOCK_ALIGN)
  25
  26 struct morus1280_block {
  27         u64 words[MORUS_BLOCK_WORDS];
  28 };
  29
  30 union morus1280_block_in {
  31         __le64 words[MORUS_BLOCK_WORDS];
  32         u8 bytes[MORUS1280_BLOCK_SIZE];
  33 };
  34
  35 struct morus1280_state {
  36         struct morus1280_block s[MORUS_STATE_BLOCKS];
  37 };
  38
  39 struct morus1280_ctx {
  40         struct morus1280_block key;
  41 };
  42
  43 struct morus1280_ops {
  44         int (*skcipher_walk_init)(struct skcipher_walk *walk,
  45                                   struct aead_request *req, bool atomic);
  46
  47         void (*crypt_chunk)(struct morus1280_state *state,
  48                             u8 *dst, const u8 *src, unsigned int size);
  49 };
  50
  51 static const struct morus1280_block crypto_morus1280_const[1] = {
  52         { .words = {
  53                 U64_C(0x0d08050302010100),
  54                 U64_C(0x6279e99059372215),
  55                 U64_C(0xf12fc26d55183ddb),
  56                 U64_C(0xdd28b57342311120),
  57         } },
  58 };
  59
  60 static void crypto_morus1280_round(struct morus1280_block *b0,
  61                                    struct morus1280_block *b1,
  62                                    struct morus1280_block *b2,
  63                                    struct morus1280_block *b3,
  64                                    struct morus1280_block *b4,
  65                                    const struct morus1280_block *m,
  66                                    unsigned int b, unsigned int w)
  67 {
  68         unsigned int i;
  69         struct morus1280_block tmp;
  70
  71         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
  72                 b0->words[i] ^= b1->words[i] & b2->words[i];
  73                 b0->words[i] ^= b3->words[i];
  74                 b0->words[i] ^= m->words[i];
  75                 b0->words[i] = rol64(b0->words[i], b);
  76         }
  77
  78         tmp = *b3;
  79         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
  80                 b3->words[(i + w) % MORUS_BLOCK_WORDS] = tmp.words[i];
  81 }
  82
  83 static void crypto_morus1280_update(struct morus1280_state *state,
  84                                     const struct morus1280_block *m)
  85 {
  86         static const struct morus1280_block z = {};
  87
  88         struct morus1280_block *s = state->s;
  89
  90         crypto_morus1280_round(&s[0], &s[1], &s[2], &s[3], &s[4], &z, 13, 1);
  91         crypto_morus1280_round(&s[1], &s[2], &s[3], &s[4], &s[0], m,  46, 2);
  92         crypto_morus1280_round(&s[2], &s[3], &s[4], &s[0], &s[1], m,  38, 3);
  93         crypto_morus1280_round(&s[3], &s[4], &s[0], &s[1], &s[2], m,   7, 2);
  94         crypto_morus1280_round(&s[4], &s[0], &s[1], &s[2], &s[3], m,   4, 1);
  95 }
  96
  97 static void crypto_morus1280_load_a(struct morus1280_block *dst, const u8 *src)
  98 {
  99         unsigned int i;
 100         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 101                 dst->words[i] = le64_to_cpu(*(const __le64 *)src);
 102                 src += MORUS1280_WORD_SIZE;
 103         }
 104 }
 105
 106 static void crypto_morus1280_load_u(struct morus1280_block *dst, const u8 *src)
 107 {
 108         unsigned int i;
 109         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 110                 dst->words[i] = get_unaligned_le64(src);
 111                 src += MORUS1280_WORD_SIZE;
 112         }
 113 }
 114
 115 static void crypto_morus1280_load(struct morus1280_block *dst, const u8 *src)
 116 {
 117         if (MORUS1280_ALIGNED(src))
 118                 crypto_morus1280_load_a(dst, src);
 119         else
 120                 crypto_morus1280_load_u(dst, src);
 121 }
 122
 123 static void crypto_morus1280_store_a(u8 *dst, const struct morus1280_block *src)
 124 {
 125         unsigned int i;
 126         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 127                 *(__le64 *)dst = cpu_to_le64(src->words[i]);
 128                 dst += MORUS1280_WORD_SIZE;
 129         }
 130 }
 131
 132 static void crypto_morus1280_store_u(u8 *dst, const struct morus1280_block *src)
 133 {
 134         unsigned int i;
 135         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 136                 put_unaligned_le64(src->words[i], dst);
 137                 dst += MORUS1280_WORD_SIZE;
 138         }
 139 }
 140
 141 static void crypto_morus1280_store(u8 *dst, const struct morus1280_block *src)
 142 {
 143         if (MORUS1280_ALIGNED(dst))
 144                 crypto_morus1280_store_a(dst, src);
 145         else
 146                 crypto_morus1280_store_u(dst, src);
 147 }
 148
 149 static void crypto_morus1280_ad(struct morus1280_state *state, const u8 *src,
 150                                 unsigned int size)
 151 {
 152         struct morus1280_block m;
 153
 154         if (MORUS1280_ALIGNED(src)) {
 155                 while (size >= MORUS1280_BLOCK_SIZE) {
 156                         crypto_morus1280_load_a(&m, src);
 157                         crypto_morus1280_update(state, &m);
 158
 159                         size -= MORUS1280_BLOCK_SIZE;
 160                         src += MORUS1280_BLOCK_SIZE;
 161                 }
 162         } else {
 163                 while (size >= MORUS1280_BLOCK_SIZE) {
 164                         crypto_morus1280_load_u(&m, src);
 165                         crypto_morus1280_update(state, &m);
 166
 167                         size -= MORUS1280_BLOCK_SIZE;
 168                         src += MORUS1280_BLOCK_SIZE;
 169                 }
 170         }
 171 }
 172
 173 static void crypto_morus1280_core(const struct morus1280_state *state,
 174                                   struct morus1280_block *blk)
 175 {
 176         unsigned int i;
 177
 178         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 179                 blk->words[(i + 3) % MORUS_BLOCK_WORDS] ^= state->s[1].words[i];
 180
 181         for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
 182                 blk->words[i] ^= state->s[0].words[i];
 183                 blk->words[i] ^= state->s[2].words[i] & state->s[3].words[i];
 184         }
 185 }
 186
 187 static void crypto_morus1280_encrypt_chunk(struct morus1280_state *state,
 188                                            u8 *dst, const u8 *src,
 189                                            unsigned int size)
 190 {
 191         struct morus1280_block c, m;
 192
 193         if (MORUS1280_ALIGNED(src) && MORUS1280_ALIGNED(dst)) {
 194                 while (size >= MORUS1280_BLOCK_SIZE) {
 195                         crypto_morus1280_load_a(&m, src);
 196                         c = m;
 197                         crypto_morus1280_core(state, &c);
 198                         crypto_morus1280_store_a(dst, &c);
 199                         crypto_morus1280_update(state, &m);
 200
 201                         src += MORUS1280_BLOCK_SIZE;
 202                         dst += MORUS1280_BLOCK_SIZE;
 203                         size -= MORUS1280_BLOCK_SIZE;
 204                 }
 205         } else {
 206                 while (size >= MORUS1280_BLOCK_SIZE) {
 207                         crypto_morus1280_load_u(&m, src);
 208                         c = m;
 209                         crypto_morus1280_core(state, &c);
 210                         crypto_morus1280_store_u(dst, &c);
 211                         crypto_morus1280_update(state, &m);
 212
 213                         src += MORUS1280_BLOCK_SIZE;
 214                         dst += MORUS1280_BLOCK_SIZE;
 215                         size -= MORUS1280_BLOCK_SIZE;
 216                 }
 217         }
 218
 219         if (size > 0) {
 220                 union morus1280_block_in tail;
 221
 222                 memcpy(tail.bytes, src, size);
 223                 memset(tail.bytes + size, 0, MORUS1280_BLOCK_SIZE - size);
 224
 225                 crypto_morus1280_load_a(&m, tail.bytes);
 226                 c = m;
 227                 crypto_morus1280_core(state, &c);
 228                 crypto_morus1280_store_a(tail.bytes, &c);
 229                 crypto_morus1280_update(state, &m);
 230
 231                 memcpy(dst, tail.bytes, size);
 232         }
 233 }
 234
 235 static void crypto_morus1280_decrypt_chunk(struct morus1280_state *state,
 236                                            u8 *dst, const u8 *src,
 237                                            unsigned int size)
 238 {
 239         struct morus1280_block m;
 240
 241         if (MORUS1280_ALIGNED(src) && MORUS1280_ALIGNED(dst)) {
 242                 while (size >= MORUS1280_BLOCK_SIZE) {
 243                         crypto_morus1280_load_a(&m, src);
 244                         crypto_morus1280_core(state, &m);
 245                         crypto_morus1280_store_a(dst, &m);
 246                         crypto_morus1280_update(state, &m);
 247
 248                         src += MORUS1280_BLOCK_SIZE;
 249                         dst += MORUS1280_BLOCK_SIZE;
 250                         size -= MORUS1280_BLOCK_SIZE;
 251                 }
 252         } else {
 253                 while (size >= MORUS1280_BLOCK_SIZE) {
 254                         crypto_morus1280_load_u(&m, src);
 255                         crypto_morus1280_core(state, &m);
 256                         crypto_morus1280_store_u(dst, &m);
 257                         crypto_morus1280_update(state, &m);
 258
 259                         src += MORUS1280_BLOCK_SIZE;
 260                         dst += MORUS1280_BLOCK_SIZE;
 261                         size -= MORUS1280_BLOCK_SIZE;
 262                 }
 263         }
 264
 265         if (size > 0) {
 266                 union morus1280_block_in tail;
 267
 268                 memcpy(tail.bytes, src, size);
 269                 memset(tail.bytes + size, 0, MORUS1280_BLOCK_SIZE - size);
 270
 271                 crypto_morus1280_load_a(&m, tail.bytes);
 272                 crypto_morus1280_core(state, &m);
 273                 crypto_morus1280_store_a(tail.bytes, &m);
 274                 memset(tail.bytes + size, 0, MORUS1280_BLOCK_SIZE - size);
 275                 crypto_morus1280_load_a(&m, tail.bytes);
 276                 crypto_morus1280_update(state, &m);
 277
 278                 memcpy(dst, tail.bytes, size);
 279         }
 280 }
 281
 282 static void crypto_morus1280_init(struct morus1280_state *state,
 283                                   const struct morus1280_block *key,
 284                                   const u8 *iv)
 285 {
 286         static const struct morus1280_block z = {};
 287
 288         union morus1280_block_in tmp;
 289         unsigned int i;
 290
 291         memcpy(tmp.bytes, iv, MORUS_NONCE_SIZE);
 292         memset(tmp.bytes + MORUS_NONCE_SIZE, 0,
 293                MORUS1280_BLOCK_SIZE - MORUS_NONCE_SIZE);
 294
 295         crypto_morus1280_load(&state->s[0], tmp.bytes);
 296         state->s[1] = *key;
 297         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 298                 state->s[2].words[i] = U64_C(0xFFFFFFFFFFFFFFFF);
 299         state->s[3] = z;
 300         state->s[4] = crypto_morus1280_const[0];
 301
 302         for (i = 0; i < 16; i++)
 303                 crypto_morus1280_update(state, &z);
 304
 305         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 306                 state->s[1].words[i] ^= key->words[i];
 307 }
 308
 309 static void crypto_morus1280_process_ad(struct morus1280_state *state,
 310                                         struct scatterlist *sg_src,
 311                                         unsigned int assoclen)
 312 {
 313         struct scatter_walk walk;
 314         struct morus1280_block m;
 315         union morus1280_block_in buf;
 316         unsigned int pos = 0;
 317
 318         scatterwalk_start(&walk, sg_src);
 319         while (assoclen != 0) {
 320                 unsigned int size = scatterwalk_clamp(&walk, assoclen);
 321                 unsigned int left = size;
 322                 void *mapped = scatterwalk_map(&walk);
 323                 const u8 *src = (const u8 *)mapped;
 324
 325                 if (pos + size >= MORUS1280_BLOCK_SIZE) {
 326                         if (pos > 0) {
 327                                 unsigned int fill = MORUS1280_BLOCK_SIZE - pos;
 328                                 memcpy(buf.bytes + pos, src, fill);
 329
 330                                 crypto_morus1280_load_a(&m, buf.bytes);
 331                                 crypto_morus1280_update(state, &m);
 332
 333                                 pos = 0;
 334                                 left -= fill;
 335                                 src += fill;
 336                         }
 337
 338                         crypto_morus1280_ad(state, src, left);
 339                         src += left & ~(MORUS1280_BLOCK_SIZE - 1);
 340                         left &= MORUS1280_BLOCK_SIZE - 1;
 341                 }
 342
 343                 memcpy(buf.bytes + pos, src, left);
 344
 345                 pos += left;
 346                 assoclen -= size;
 347                 scatterwalk_unmap(mapped);
 348                 scatterwalk_advance(&walk, size);
 349                 scatterwalk_done(&walk, 0, assoclen);
 350         }
 351
 352         if (pos > 0) {
 353                 memset(buf.bytes + pos, 0, MORUS1280_BLOCK_SIZE - pos);
 354
 355                 crypto_morus1280_load_a(&m, buf.bytes);
 356                 crypto_morus1280_update(state, &m);
 357         }
 358 }
 359
 360 static void crypto_morus1280_process_crypt(struct morus1280_state *state,
 361                                            struct aead_request *req,
 362                                            const struct morus1280_ops *ops)
 363 {
 364         struct skcipher_walk walk;
 365
 366         ops->skcipher_walk_init(&walk, req, false);
 367
 368         while (walk.nbytes) {
 369                 unsigned int nbytes = walk.nbytes;
 370
 371                 if (nbytes < walk.total)
 372                         nbytes = round_down(nbytes, walk.stride);
 373
 374                 ops->crypt_chunk(state, walk.dst.virt.addr, walk.src.virt.addr,
 375                                  nbytes);
 376
 377                 skcipher_walk_done(&walk, walk.nbytes - nbytes);
 378         }
 379 }
 380
 381 static void crypto_morus1280_final(struct morus1280_state *state,
 382                                    struct morus1280_block *tag_xor,
 383                                    u64 assoclen, u64 cryptlen)
 384 {
 385         struct morus1280_block tmp;
 386         unsigned int i;
 387
 388         tmp.words[0] = assoclen * 8;
 389         tmp.words[1] = cryptlen * 8;
 390         tmp.words[2] = 0;
 391         tmp.words[3] = 0;
 392
 393         for (i = 0; i < MORUS_BLOCK_WORDS; i++)
 394                 state->s[4].words[i] ^= state->s[0].words[i];
 395
 396         for (i = 0; i < 10; i++)
 397                 crypto_morus1280_update(state, &tmp);
 398
 399         crypto_morus1280_core(state, tag_xor);
 400 }
 401
 402 static int crypto_morus1280_setkey(struct crypto_aead *aead, const u8 *key,
 403                                    unsigned int keylen)
 404 {
 405         struct morus1280_ctx *ctx = crypto_aead_ctx(aead);
 406         union morus1280_block_in tmp;
 407
 408         if (keylen == MORUS1280_BLOCK_SIZE)
 409                 crypto_morus1280_load(&ctx->key, key);
 410         else if (keylen == MORUS1280_BLOCK_SIZE / 2) {
 411                 memcpy(tmp.bytes, key, keylen);
 412                 memcpy(tmp.bytes + keylen, key, keylen);
 413
 414                 crypto_morus1280_load(&ctx->key, tmp.bytes);
 415         } else {
 416                 crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
 417                 return -EINVAL;
 418         }
 419
 420         return 0;
 421 }
 422
 423 static int crypto_morus1280_setauthsize(struct crypto_aead *tfm,
 424                                         unsigned int authsize)
 425 {
 426         return (authsize <= MORUS_MAX_AUTH_SIZE) ? 0 : -EINVAL;
 427 }
 428
 429 static void crypto_morus1280_crypt(struct aead_request *req,
 430                                    struct morus1280_block *tag_xor,
 431                                    unsigned int cryptlen,
 432                                    const struct morus1280_ops *ops)
 433 {
 434         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 435         struct morus1280_ctx *ctx = crypto_aead_ctx(tfm);
 436         struct morus1280_state state;
 437
 438         crypto_morus1280_init(&state, &ctx->key, req->iv);
 439         crypto_morus1280_process_ad(&state, req->src, req->assoclen);
 440         crypto_morus1280_process_crypt(&state, req, ops);
 441         crypto_morus1280_final(&state, tag_xor, req->assoclen, cryptlen);
 442 }
 443
 444 static int crypto_morus1280_encrypt(struct aead_request *req)
 445 {
 446         static const struct morus1280_ops ops = {
 447                 .skcipher_walk_init = skcipher_walk_aead_encrypt,
 448                 .crypt_chunk = crypto_morus1280_encrypt_chunk,
 449         };
 450
 451         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 452         struct morus1280_block tag = {};
 453         union morus1280_block_in tag_out;
 454         unsigned int authsize = crypto_aead_authsize(tfm);
 455         unsigned int cryptlen = req->cryptlen;
 456
 457         crypto_morus1280_crypt(req, &tag, cryptlen, &ops);
 458         crypto_morus1280_store(tag_out.bytes, &tag);
 459
 460         scatterwalk_map_and_copy(tag_out.bytes, req->dst,
 461                                  req->assoclen + cryptlen, authsize, 1);
 462         return 0;
 463 }
 464
 465 static int crypto_morus1280_decrypt(struct aead_request *req)
 466 {
 467         static const struct morus1280_ops ops = {
 468                 .skcipher_walk_init = skcipher_walk_aead_decrypt,
 469                 .crypt_chunk = crypto_morus1280_decrypt_chunk,
 470         };
 471         static const u8 zeros[MORUS1280_BLOCK_SIZE] = {};
 472
 473         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 474         union morus1280_block_in tag_in;
 475         struct morus1280_block tag;
 476         unsigned int authsize = crypto_aead_authsize(tfm);
 477         unsigned int cryptlen = req->cryptlen - authsize;
 478
 479         scatterwalk_map_and_copy(tag_in.bytes, req->src,
 480                                  req->assoclen + cryptlen, authsize, 0);
 481
 482         crypto_morus1280_load(&tag, tag_in.bytes);
 483         crypto_morus1280_crypt(req, &tag, cryptlen, &ops);
 484         crypto_morus1280_store(tag_in.bytes, &tag);
 485
 486         return crypto_memneq(tag_in.bytes, zeros, authsize) ? -EBADMSG : 0;
 487 }
 488
 489 static int crypto_morus1280_init_tfm(struct crypto_aead *tfm)
 490 {
 491         return 0;
 492 }
 493
 494 static void crypto_morus1280_exit_tfm(struct crypto_aead *tfm)
 495 {
 496 }
 497
 498 static struct aead_alg crypto_morus1280_alg = {
 499         .setkey = crypto_morus1280_setkey,
 500         .setauthsize = crypto_morus1280_setauthsize,
 501         .encrypt = crypto_morus1280_encrypt,
 502         .decrypt = crypto_morus1280_decrypt,
 503         .init = crypto_morus1280_init_tfm,
 504         .exit = crypto_morus1280_exit_tfm,
 505
 506         .ivsize = MORUS_NONCE_SIZE,
 507         .maxauthsize = MORUS_MAX_AUTH_SIZE,
 508         .chunksize = MORUS1280_BLOCK_SIZE,
 509
 510         .base = {
 511                 .cra_blocksize = 1,
 512                 .cra_ctxsize = sizeof(struct morus1280_ctx),
 513                 .cra_alignmask = 0,
 514
 515                 .cra_priority = 100,
 516
 517                 .cra_name = "morus1280",
 518                 .cra_driver_name = "morus1280-generic",
 519
 520                 .cra_module = THIS_MODULE,
 521         }
 522 };
 523
 524
 525 static int __init crypto_morus1280_module_init(void)
 526 {
 527         return crypto_register_aead(&crypto_morus1280_alg);
 528 }
 529
 530 static void __exit crypto_morus1280_module_exit(void)
 531 {
 532         crypto_unregister_aead(&crypto_morus1280_alg);
 533 }
 534
 535 subsys_initcall(crypto_morus1280_module_init);
 536 module_exit(crypto_morus1280_module_exit);
 537
 538 MODULE_LICENSE("GPL");
 539 MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
 540 MODULE_DESCRIPTION("MORUS-1280 AEAD algorithm");
 541 MODULE_ALIAS_CRYPTO("morus1280");
 542 MODULE_ALIAS_CRYPTO("morus1280-generic");