gost_grasshopper_cipher.c

   1 /*
   2  * Maxim Tishkov 2016
   3  * This file is distributed under the same license as OpenSSL
   4  */
   5
   6 #include "gost_grasshopper_cipher.h"
   7 #include "gost_grasshopper_defines.h"
   8 #include "gost_grasshopper_math.h"
   9 #include "gost_grasshopper_core.h"
  10
  11 #include <openssl/evp.h>
  12 #include <openssl/rand.h>
  13 #include <openssl/err.h>
  14
  15 #include <string.h>
  16 #include <byteswap.h>
  17
  18 #include "gost_lcl.h"
  19 #include "e_gost_err.h"
  20
  21 enum GRASSHOPPER_CIPHER_TYPE {
  22     GRASSHOPPER_CIPHER_ECB = 0,
  23     GRASSHOPPER_CIPHER_CBC,
  24     GRASSHOPPER_CIPHER_OFB,
  25     GRASSHOPPER_CIPHER_CFB,
  26     GRASSHOPPER_CIPHER_CTR,
  27     GRASSHOPPER_CIPHER_CTRACPKM,
  28                 GRASSHOPPER_CIPHER_MGM,
  29 };
  30
  31 static EVP_CIPHER *gost_grasshopper_ciphers[7] = {
  32     [GRASSHOPPER_CIPHER_ECB] = NULL,
  33     [GRASSHOPPER_CIPHER_CBC] = NULL,
  34     [GRASSHOPPER_CIPHER_OFB] = NULL,
  35     [GRASSHOPPER_CIPHER_CFB] = NULL,
  36     [GRASSHOPPER_CIPHER_CTR] = NULL,
  37     [GRASSHOPPER_CIPHER_CTRACPKM] = NULL,
  38                 [GRASSHOPPER_CIPHER_MGM] = NULL,
  39 };
  40
  41 static GRASSHOPPER_INLINE void
  42 gost_grasshopper_cipher_destroy_ofb(gost_grasshopper_cipher_ctx * c);
  43 static GRASSHOPPER_INLINE void
  44 gost_grasshopper_cipher_destroy_ctr(gost_grasshopper_cipher_ctx * c);
  45 static GRASSHOPPER_INLINE void
  46 gost_grasshopper_cipher_destroy_mgm(gost_grasshopper_cipher_ctx * c);
  47
  48 struct GRASSHOPPER_CIPHER_PARAMS {
  49     int nid;
  50     grasshopper_init_cipher_func init_cipher;
  51     grasshopper_do_cipher_func do_cipher;
  52     grasshopper_destroy_cipher_func destroy_cipher;
  53     int block_size;
  54     int ctx_size;
  55     int iv_size;
  56     bool padding;
  57 };
  58
  59 static struct GRASSHOPPER_CIPHER_PARAMS gost_cipher_params[7] = {
  60     [GRASSHOPPER_CIPHER_ECB] = {
  61                                 NID_grasshopper_ecb,
  62                                 gost_grasshopper_cipher_init_ecb,
  63                                 gost_grasshopper_cipher_do_ecb,
  64                                 NULL,
  65                                 16,
  66                                 sizeof(gost_grasshopper_cipher_ctx),
  67                                 0,
  68                                 true}
  69     ,
  70     [GRASSHOPPER_CIPHER_CBC] = {
  71                                 NID_grasshopper_cbc,
  72                                 gost_grasshopper_cipher_init_cbc,
  73                                 gost_grasshopper_cipher_do_cbc,
  74                                 NULL,
  75                                 16,
  76                                 sizeof(gost_grasshopper_cipher_ctx),
  77                                 16,
  78                                 true}
  79     ,
  80     [GRASSHOPPER_CIPHER_OFB] = {
  81                                 NID_grasshopper_ofb,
  82                                 gost_grasshopper_cipher_init_ofb,
  83                                 gost_grasshopper_cipher_do_ofb,
  84                                 gost_grasshopper_cipher_destroy_ofb,
  85                                 1,
  86                                 sizeof(gost_grasshopper_cipher_ctx_ofb),
  87                                 16,
  88                                 false}
  89     ,
  90     [GRASSHOPPER_CIPHER_CFB] = {
  91                                 NID_grasshopper_cfb,
  92                                 gost_grasshopper_cipher_init_cfb,
  93                                 gost_grasshopper_cipher_do_cfb,
  94                                 NULL,
  95                                 1,
  96                                 sizeof(gost_grasshopper_cipher_ctx),
  97                                 16,
  98                                 false}
  99     ,
 100     [GRASSHOPPER_CIPHER_CTR] = {
 101                                 NID_grasshopper_ctr,
 102                                 gost_grasshopper_cipher_init_ctr,
 103                                 gost_grasshopper_cipher_do_ctr,
 104                                 gost_grasshopper_cipher_destroy_ctr,
 105                                 1,
 106                                 sizeof(gost_grasshopper_cipher_ctx_ctr),
 107                                 /* IV size is set to match full block, to make it responsibility of
 108                                  * user to assign correct values (IV || 0), and to make naive context
 109                                  * copy possible (for software such as openssh) */
 110                                 16,
 111                                 false}
 112     ,
 113     [GRASSHOPPER_CIPHER_CTRACPKM] = {
 114                                      NID_id_tc26_cipher_gostr3412_2015_kuznyechik_ctracpkm,
 115                                      gost_grasshopper_cipher_init_ctracpkm,
 116                                      gost_grasshopper_cipher_do_ctracpkm,
 117                                      gost_grasshopper_cipher_destroy_ctr,
 118                                      1,
 119                                      sizeof(gost_grasshopper_cipher_ctx_ctr),
 120                                      16,
 121                                      false}
 122     ,
 123 #ifdef NID_kuznyechik_mgm
 124     [GRASSHOPPER_CIPHER_MGM] = {
 125                                 NID_kuznyechik_mgm,
 126                                 gost_grasshopper_cipher_init_mgm,
 127                                 gost_grasshopper_cipher_do_mgm,
 128                                 gost_grasshopper_cipher_destroy_mgm,
 129                                 1,
 130                                 sizeof(gost_grasshopper_cipher_ctx_mgm),
 131                                 16,
 132                                 false}
 133     ,
 134 #else
 135     [GRASSHOPPER_CIPHER_MGM] = {
 136                                 NID_undef,
 137                                 NULL,
 138                                 NULL,
 139                                 NULL,
 140                                 0,
 141                                 0,
 142                                 0,
 143                                 false}
 144     ,
 145 #endif
 146 };
 147
 148 /* first 256 bit of D from draft-irtf-cfrg-re-keying-12 */
 149 static const unsigned char ACPKM_D_2018[] = {
 150     0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /*  64 bit */
 151     0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 128 bit */
 152     0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
 153     0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 256 bit */
 154 };
 155
 156 static void acpkm_next(gost_grasshopper_cipher_ctx * c)
 157 {
 158     unsigned char newkey[GRASSHOPPER_KEY_SIZE];
 159     const int J = GRASSHOPPER_KEY_SIZE / GRASSHOPPER_BLOCK_SIZE;
 160     int n;
 161
 162     for (n = 0; n < J; n++) {
 163         const unsigned char *D_n = &ACPKM_D_2018[n * GRASSHOPPER_BLOCK_SIZE];
 164
 165         grasshopper_encrypt_block(&c->encrypt_round_keys,
 166                                   (grasshopper_w128_t *) D_n,
 167                                   (grasshopper_w128_t *) & newkey[n *
 168                                                                   GRASSHOPPER_BLOCK_SIZE],
 169                                   &c->buffer);
 170     }
 171     gost_grasshopper_cipher_key(c, newkey);
 172 }
 173
 174 /* Set 256 bit  key into context */
 175 GRASSHOPPER_INLINE void
 176 gost_grasshopper_cipher_key(gost_grasshopper_cipher_ctx * c, const uint8_t *k)
 177 {
 178     int i;
 179     for (i = 0; i < 2; i++) {
 180         grasshopper_copy128(&c->key.k.k[i],
 181                             (const grasshopper_w128_t *)(k + i * 16));
 182     }
 183
 184     grasshopper_set_encrypt_key(&c->encrypt_round_keys, &c->key);
 185     grasshopper_set_decrypt_key(&c->decrypt_round_keys, &c->key);
 186 }
 187
 188 /* Set master 256-bit key to be used in TLSTREE calculation into context */
 189 GRASSHOPPER_INLINE void
 190 gost_grasshopper_master_key(gost_grasshopper_cipher_ctx * c, const uint8_t *k)
 191 {
 192     int i;
 193     for (i = 0; i < 2; i++) {
 194         grasshopper_copy128(&c->master_key.k.k[i],
 195                             (const grasshopper_w128_t *)(k + i * 16));
 196     }
 197 }
 198
 199 /* Cleans up key from context */
 200 GRASSHOPPER_INLINE void
 201 gost_grasshopper_cipher_destroy(gost_grasshopper_cipher_ctx * c)
 202 {
 203     int i;
 204     for (i = 0; i < 2; i++) {
 205         grasshopper_zero128(&c->key.k.k[i]);
 206         grasshopper_zero128(&c->master_key.k.k[i]);
 207     }
 208     for (i = 0; i < GRASSHOPPER_ROUND_KEYS_COUNT; i++) {
 209         grasshopper_zero128(&c->encrypt_round_keys.k[i]);
 210     }
 211     for (i = 0; i < GRASSHOPPER_ROUND_KEYS_COUNT; i++) {
 212         grasshopper_zero128(&c->decrypt_round_keys.k[i]);
 213     }
 214     grasshopper_zero128(&c->buffer);
 215 }
 216
 217 static GRASSHOPPER_INLINE void
 218 gost_grasshopper_cipher_destroy_ofb(gost_grasshopper_cipher_ctx * c)
 219 {
 220     gost_grasshopper_cipher_ctx_ofb *ctx =
 221         (gost_grasshopper_cipher_ctx_ofb *) c;
 222
 223     grasshopper_zero128(&ctx->buffer1);
 224 }
 225
 226 static GRASSHOPPER_INLINE void
 227 gost_grasshopper_cipher_destroy_ctr(gost_grasshopper_cipher_ctx * c)
 228 {
 229     gost_grasshopper_cipher_ctx_ctr *ctx =
 230         (gost_grasshopper_cipher_ctx_ctr *) c;
 231
 232     grasshopper_zero128(&ctx->partial_buffer);
 233 }
 234
 235 static GRASSHOPPER_INLINE void
 236 gost_grasshopper_cipher_destroy_mgm(gost_grasshopper_cipher_ctx * c)
 237 {
 238     gost_grasshopper_cipher_ctx_mgm *ctx =
 239         (gost_grasshopper_cipher_ctx_mgm *) c;
 240
 241     grasshopper_zero128(&ctx->partial_buffer);
 242 }
 243
 244 int gost_grasshopper_cipher_init(EVP_CIPHER_CTX *ctx,
 245                                  const unsigned char *key,
 246                                  const unsigned char *iv, int enc)
 247 {
 248     gost_grasshopper_cipher_ctx *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 249
 250     if (EVP_CIPHER_CTX_get_app_data(ctx) == NULL) {
 251         EVP_CIPHER_CTX_set_app_data(ctx, EVP_CIPHER_CTX_get_cipher_data(ctx));
 252     }
 253
 254     if (key != NULL) {
 255         gost_grasshopper_cipher_key(c, key);
 256         gost_grasshopper_master_key(c, key);
 257     }
 258
 259     if (iv != NULL) {
 260         if (c->type == GRASSHOPPER_CIPHER_MGM) {
 261                                         gost_grasshopper_cipher_ctx_mgm *m = (gost_grasshopper_cipher_ctx_mgm *)c;
 262
 263                                         /* 1st bit should be 0*/
 264                                         if (iv[0] > 127) {
 265                                                 GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_INIT, GOST_R_INVALID_IV_LENGTH);
 266                                                 return 0;
 267                                         }
 268                                         memcpy(m->mgm_iv, iv, 16);
 269                                         *(unsigned char *)(m->mgm_iv) += 128;
 270                                 }
 271         memcpy((unsigned char *)EVP_CIPHER_CTX_original_iv(ctx), iv,
 272                EVP_CIPHER_CTX_iv_length(ctx));
 273     }
 274
 275     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx),
 276            EVP_CIPHER_CTX_original_iv(ctx), EVP_CIPHER_CTX_iv_length(ctx));
 277
 278     grasshopper_zero128(&c->buffer);
 279
 280     return 1;
 281 }
 282
 283 GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ecb(EVP_CIPHER_CTX *ctx, const unsigned char
 284                                                         *key, const unsigned char
 285                                                         *iv, int enc)
 286 {
 287     gost_grasshopper_cipher_ctx *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 288     c->type = GRASSHOPPER_CIPHER_ECB;
 289     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 290 }
 291
 292 GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_cbc(EVP_CIPHER_CTX *ctx, const unsigned char
 293                                                         *key, const unsigned char
 294                                                         *iv, int enc)
 295 {
 296     gost_grasshopper_cipher_ctx *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 297     c->type = GRASSHOPPER_CIPHER_CBC;
 298     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 299 }
 300
 301 GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ofb(EVP_CIPHER_CTX *ctx, const unsigned char
 302                                                         *key, const unsigned char
 303                                                         *iv, int enc)
 304 {
 305     gost_grasshopper_cipher_ctx_ofb *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 306
 307     c->c.type = GRASSHOPPER_CIPHER_OFB;
 308
 309     grasshopper_zero128(&c->buffer1);
 310
 311     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 312 }
 313
 314 GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_cfb(EVP_CIPHER_CTX *ctx, const unsigned char
 315                                                         *key, const unsigned char
 316                                                         *iv, int enc)
 317 {
 318     gost_grasshopper_cipher_ctx *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 319     c->type = GRASSHOPPER_CIPHER_CFB;
 320     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 321 }
 322
 323 GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ctr(EVP_CIPHER_CTX *ctx, const unsigned char
 324                                                         *key, const unsigned char
 325                                                         *iv, int enc)
 326 {
 327     gost_grasshopper_cipher_ctx_ctr *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 328
 329     c->c.type = GRASSHOPPER_CIPHER_CTR;
 330     EVP_CIPHER_CTX_set_num(ctx, 0);
 331
 332     grasshopper_zero128(&c->partial_buffer);
 333
 334     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 335 }
 336
 337 GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ctracpkm(EVP_CIPHER_CTX
 338                                                              *ctx, const unsigned
 339                                                              char *key, const unsigned
 340                                                              char *iv, int enc)
 341 {
 342     gost_grasshopper_cipher_ctx_ctr *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 343
 344     /* NB: setting type makes EVP do_cipher callback useless */
 345     c->c.type = GRASSHOPPER_CIPHER_CTRACPKM;
 346     EVP_CIPHER_CTX_set_num(ctx, 0);
 347     c->section_size = 4096;
 348
 349     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 350 }
 351
 352 GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_mgm(EVP_CIPHER_CTX *ctx, const unsigned char
 353                                                         *key, const unsigned char
 354                                                         *iv, int enc)
 355 {
 356     gost_grasshopper_cipher_ctx_mgm *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 357
 358     c->c.type = GRASSHOPPER_CIPHER_MGM;
 359                 c->taglen = 16;
 360     EVP_CIPHER_CTX_set_num(ctx, 0);
 361
 362     grasshopper_zero128(&c->partial_buffer);
 363
 364     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 365 }
 366
 367 GRASSHOPPER_INLINE int gost_grasshopper_cipher_do(EVP_CIPHER_CTX *ctx,
 368                                                   unsigned char *out,
 369                                                   const unsigned char *in,
 370                                                   size_t inl)
 371 {
 372     gost_grasshopper_cipher_ctx *c =
 373         (gost_grasshopper_cipher_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
 374     struct GRASSHOPPER_CIPHER_PARAMS *params = &gost_cipher_params[c->type];
 375
 376     return params->do_cipher(ctx, out, in, inl);
 377 }
 378
 379 int gost_grasshopper_cipher_do_ecb(EVP_CIPHER_CTX *ctx, unsigned char *out,
 380                                    const unsigned char *in, size_t inl)
 381 {
 382     gost_grasshopper_cipher_ctx *c =
 383         (gost_grasshopper_cipher_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
 384     bool encrypting = (bool) EVP_CIPHER_CTX_encrypting(ctx);
 385     const unsigned char *current_in = in;
 386     unsigned char *current_out = out;
 387     size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
 388     size_t i;
 389
 390     for (i = 0; i < blocks;
 391          i++, current_in += GRASSHOPPER_BLOCK_SIZE, current_out +=
 392          GRASSHOPPER_BLOCK_SIZE) {
 393         if (encrypting) {
 394             grasshopper_encrypt_block(&c->encrypt_round_keys,
 395                                       (grasshopper_w128_t *) current_in,
 396                                       (grasshopper_w128_t *) current_out,
 397                                       &c->buffer);
 398         } else {
 399             grasshopper_decrypt_block(&c->decrypt_round_keys,
 400                                       (grasshopper_w128_t *) current_in,
 401                                       (grasshopper_w128_t *) current_out,
 402                                       &c->buffer);
 403         }
 404     }
 405
 406     return 1;
 407 }
 408
 409 int gost_grasshopper_cipher_do_cbc(EVP_CIPHER_CTX *ctx, unsigned char *out,
 410                                    const unsigned char *in, size_t inl)
 411 {
 412     gost_grasshopper_cipher_ctx *c =
 413         (gost_grasshopper_cipher_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
 414     unsigned char *iv = EVP_CIPHER_CTX_iv_noconst(ctx);
 415     bool encrypting = (bool) EVP_CIPHER_CTX_encrypting(ctx);
 416     const unsigned char *current_in = in;
 417     unsigned char *current_out = out;
 418     grasshopper_w128_t *currentInputBlock;
 419     grasshopper_w128_t *currentOutputBlock;
 420     size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
 421     size_t i;
 422     grasshopper_w128_t *currentBlock;
 423
 424     currentBlock = (grasshopper_w128_t *) iv;
 425
 426     for (i = 0; i < blocks;
 427          i++, current_in += GRASSHOPPER_BLOCK_SIZE, current_out +=
 428          GRASSHOPPER_BLOCK_SIZE) {
 429         currentInputBlock = (grasshopper_w128_t *) current_in;
 430         currentOutputBlock = (grasshopper_w128_t *) current_out;
 431         if (encrypting) {
 432             grasshopper_append128(currentBlock, currentInputBlock);
 433             grasshopper_encrypt_block(&c->encrypt_round_keys, currentBlock,
 434                                       currentOutputBlock, &c->buffer);
 435             grasshopper_copy128(currentBlock, currentOutputBlock);
 436         } else {
 437             grasshopper_w128_t tmp;
 438
 439             grasshopper_copy128(&tmp, currentInputBlock);
 440             grasshopper_decrypt_block(&c->decrypt_round_keys,
 441                                       currentInputBlock, currentOutputBlock,
 442                                       &c->buffer);
 443             grasshopper_append128(currentOutputBlock, currentBlock);
 444             grasshopper_copy128(currentBlock, &tmp);
 445         }
 446     }
 447
 448     return 1;
 449 }
 450
 451 void inc_counter(unsigned char *counter, size_t counter_bytes)
 452 {
 453     unsigned char c;
 454     unsigned int n = counter_bytes;
 455
 456     do {
 457         --n;
 458         c = counter[n];
 459         ++c;
 460         counter[n] = c;
 461         if (c)
 462             return;
 463     } while (n);
 464 }
 465
 466 /* increment counter (128-bit int) by 1 */
 467 static void ctr128_inc(unsigned char *counter)
 468 {
 469     inc_counter(counter, 16);
 470 }
 471
 472 int gost_grasshopper_cipher_do_ctr(EVP_CIPHER_CTX *ctx, unsigned char *out,
 473                                    const unsigned char *in, size_t inl)
 474 {
 475     gost_grasshopper_cipher_ctx_ctr *c = (gost_grasshopper_cipher_ctx_ctr *)
 476         EVP_CIPHER_CTX_get_cipher_data(ctx);
 477     unsigned char *iv = EVP_CIPHER_CTX_iv_noconst(ctx);
 478     const unsigned char *current_in = in;
 479     unsigned char *current_out = out;
 480     grasshopper_w128_t *currentInputBlock;
 481     grasshopper_w128_t *currentOutputBlock;
 482     unsigned int n = EVP_CIPHER_CTX_num(ctx);
 483     size_t lasted;
 484     size_t i;
 485
 486     while (n && inl) {
 487         *(current_out++) = *(current_in++) ^ c->partial_buffer.b[n];
 488         --inl;
 489         n = (n + 1) % GRASSHOPPER_BLOCK_SIZE;
 490     }
 491     EVP_CIPHER_CTX_set_num(ctx, n);
 492     size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
 493
 494     grasshopper_w128_t *iv_buffer = (grasshopper_w128_t *) iv;
 495     grasshopper_w128_t tmp;
 496
 497     // full parts
 498     for (i = 0; i < blocks; i++) {
 499         currentInputBlock = (grasshopper_w128_t *) current_in;
 500         currentOutputBlock = (grasshopper_w128_t *) current_out;
 501         grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer,
 502                                   &c->partial_buffer, &c->c.buffer);
 503         grasshopper_plus128(&tmp, &c->partial_buffer, currentInputBlock);
 504         grasshopper_copy128(currentOutputBlock, &tmp);
 505         ctr128_inc(iv_buffer->b);
 506         current_in += GRASSHOPPER_BLOCK_SIZE;
 507         current_out += GRASSHOPPER_BLOCK_SIZE;
 508     }
 509
 510     // last part
 511     lasted = inl - blocks * GRASSHOPPER_BLOCK_SIZE;
 512     if (lasted > 0) {
 513         currentInputBlock = (grasshopper_w128_t *) current_in;
 514         currentOutputBlock = (grasshopper_w128_t *) current_out;
 515         grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer,
 516                                   &c->partial_buffer, &c->c.buffer);
 517         for (i = 0; i < lasted; i++) {
 518             currentOutputBlock->b[i] =
 519                 c->partial_buffer.b[i] ^ currentInputBlock->b[i];
 520         }
 521         EVP_CIPHER_CTX_set_num(ctx, i);
 522         ctr128_inc(iv_buffer->b);
 523     }
 524
 525     return 1;
 526 }
 527
 528 #define GRASSHOPPER_BLOCK_MASK (GRASSHOPPER_BLOCK_SIZE - 1)
 529 static inline void apply_acpkm_grasshopper(gost_grasshopper_cipher_ctx_ctr *
 530                                            ctx, unsigned int *num)
 531 {
 532     if (!ctx->section_size || (*num < ctx->section_size))
 533         return;
 534     acpkm_next(&ctx->c);
 535     *num &= GRASSHOPPER_BLOCK_MASK;
 536 }
 537
 538 /* If meshing is not configured via ctrl (setting section_size)
 539  * this function works exactly like plain ctr */
 540 int gost_grasshopper_cipher_do_ctracpkm(EVP_CIPHER_CTX *ctx,
 541                                         unsigned char *out,
 542                                         const unsigned char *in, size_t inl)
 543 {
 544     gost_grasshopper_cipher_ctx_ctr *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 545     unsigned char *iv = EVP_CIPHER_CTX_iv_noconst(ctx);
 546     unsigned int num = EVP_CIPHER_CTX_num(ctx);
 547
 548     while ((num & GRASSHOPPER_BLOCK_MASK) && inl) {
 549         *out++ = *in++ ^ c->partial_buffer.b[num & GRASSHOPPER_BLOCK_MASK];
 550         --inl;
 551         num++;
 552     }
 553     size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
 554     size_t i;
 555     grasshopper_w128_t tmp;
 556
 557     // full parts
 558     for (i = 0; i < blocks; i++) {
 559         apply_acpkm_grasshopper(c, &num);
 560         grasshopper_encrypt_block(&c->c.encrypt_round_keys,
 561                                   (grasshopper_w128_t *) iv,
 562                                   (grasshopper_w128_t *) & c->partial_buffer,
 563                                   &c->c.buffer);
 564         grasshopper_plus128(&tmp, &c->partial_buffer,
 565                             (grasshopper_w128_t *) in);
 566         grasshopper_copy128((grasshopper_w128_t *) out, &tmp);
 567         ctr128_inc(iv);
 568         in += GRASSHOPPER_BLOCK_SIZE;
 569         out += GRASSHOPPER_BLOCK_SIZE;
 570         num += GRASSHOPPER_BLOCK_SIZE;
 571     }
 572
 573     // last part
 574     size_t lasted = inl - blocks * GRASSHOPPER_BLOCK_SIZE;
 575     if (lasted > 0) {
 576         apply_acpkm_grasshopper(c, &num);
 577         grasshopper_encrypt_block(&c->c.encrypt_round_keys,
 578                                   (grasshopper_w128_t *) iv,
 579                                   &c->partial_buffer, &c->c.buffer);
 580         for (i = 0; i < lasted; i++)
 581             out[i] = c->partial_buffer.b[i] ^ in[i];
 582         ctr128_inc(iv);
 583         num += lasted;
 584     }
 585     EVP_CIPHER_CTX_set_num(ctx, num);
 586
 587     return 1;
 588 }
 589
 590 /* ----------------------------------------------------------------------------------------------- */
 591 /*! Функция реализует операцию умножения двух элементов конечного поля \f$ \mathbb F_{2^{128}}\f$,
 592     порожденного неприводимым многочленом
 593     \f$ f(x) = x^{128} + x^7 + x^2 + x + 1 \in \mathbb F_2[x]\f$. Для умножения используется
 594     простейшая реализация, основанная на приведении по модулю после каждого шага алгоритма.        */
 595 /* ----------------------------------------------------------------------------------------------- */
 596 static void gf128_mul_uint64(uint64_t *z, uint64_t *x, uint64_t *y)
 597 {
 598  int i = 0, n = 0;
 599  uint64_t t, s0, s1;
 600
 601         BUF_reverse((unsigned char *)x, NULL, 16);
 602         BUF_reverse((unsigned char *)y, NULL, 16);
 603
 604 #ifdef L_ENDIAN
 605   s0 = x[0];
 606         s1 = x[1];
 607 #else
 608   s0 = bswap_64(x[0]);
 609         s1 = bswap_64(x[1]);
 610 #endif
 611
 612         memset(z, 0, sizeof(uint64_t)*2);
 613
 614  /* lower half */
 615 #ifdef L_ENDIAN
 616   t = y[0];
 617 #else
 618   t = bswap_64(y[0]);
 619 #endif
 620
 621  for( i = 0; i < 64; i++ ) {
 622    if( t&0x1 ) { z[0] ^= s0; z[1] ^= s1; }
 623    t >>= 1;
 624    n = s1 >> 63;
 625    s1 <<= 1; s1 ^= ( s0 >> 63 ); s0 <<= 1;
 626    if(n) s0 ^= 0x87;
 627  }
 628
 629  /* upper half */
 630 #ifdef L_ENDIAN
 631   t = y[1];
 632 #else
 633   t = bswap_64(y[1]);
 634 #endif
 635
 636  for( i = 0; i < 63; i++ ) {
 637    if( t&0x1 ) { z[0] ^= s0; z[1] ^= s1; }
 638    t >>= 1;
 639    n = s1 >> 63;
 640    s1 <<= 1; s1 ^= ( s0 >> 63 ); s0 <<= 1;
 641    if( n ) s0 ^= 0x87;
 642  }
 643
 644  if( t&0x1 ) {
 645    z[0] ^= s0;
 646    z[1] ^= s1;
 647  }
 648 #ifndef L_ENDIAN
 649    z[0] = bswap_64(z[0]);
 650    z[1] = bswap_64(z[1]);
 651 #endif
 652         BUF_reverse((unsigned char *)z, NULL, 16);
 653 }
 654
 655 static void hexdump(FILE *f, const char *title, const unsigned char *s, int l)
 656 {
 657     int n = 0;
 658
 659     fprintf(f, "%s", title);
 660     for (; n < l; ++n) {
 661         if ((n % 16) == 0)
 662             fprintf(f, "\n%04x", n);
 663         fprintf(f, " %02x", s[n]);
 664     }
 665     fprintf(f, "\n");
 666 }
 667
 668 int gost_grasshopper_cipher_do_mgm(EVP_CIPHER_CTX *ctx, unsigned char *out,
 669                                    const unsigned char *in, size_t inl)
 670 {
 671     gost_grasshopper_cipher_ctx_mgm *c = (gost_grasshopper_cipher_ctx_mgm *)
 672         EVP_CIPHER_CTX_get_cipher_data(ctx);
 673     unsigned char *iv = EVP_CIPHER_CTX_iv_noconst(ctx);
 674     const unsigned char *current_in = in;
 675     unsigned char *current_out = out;
 676     grasshopper_w128_t *currentInputBlock;
 677     grasshopper_w128_t *currentOutputBlock;
 678     unsigned int n = EVP_CIPHER_CTX_num(ctx);
 679     size_t lasted;
 680     size_t i;
 681
 682     size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
 683                 int rest_len = n % GRASSHOPPER_BLOCK_SIZE;
 684                 grasshopper_w128_t h;
 685
 686     grasshopper_w128_t *iv_buffer = (grasshopper_w128_t *) iv;
 687     grasshopper_w128_t tmp;
 688
 689 /* ======== Here we deal with associated data =========== */
 690                 if (out == NULL && c->mgm_state == mgm_associated_data) {
 691                         if (n == 0) {
 692         grasshopper_encrypt_block(&c->c.encrypt_round_keys, c->mgm_iv,
 693                                   &c->partial_buffer, &c->c.buffer);
 694                                 memcpy(c->mgm_iv, &c->partial_buffer, GRASSHOPPER_BLOCK_SIZE);
 695                                 hexdump(stderr, "Tag", c->tag, 16);
 696                         }
 697
 698                         if (rest_len != 0) {
 699                                 /* Finalize partial_data */
 700                                 if (inl + rest_len < GRASSHOPPER_BLOCK_SIZE) {
 701                                         memcpy(c->mgm_partial_buffer.b+rest_len, current_in, inl);
 702                                         n += inl;
 703                                         EVP_CIPHER_CTX_set_num(ctx, n);
 704                                         return 1;
 705                                 } else {
 706                                         memcpy(c->mgm_partial_buffer.b+rest_len, current_in, GRASSHOPPER_BLOCK_SIZE - rest_len);
 707
 708                                         grasshopper_encrypt_block(&c->c.encrypt_round_keys, c->mgm_iv,
 709                                                         &h, &c->c.buffer);
 710                                         inc_counter(c->mgm_iv->b, 8);
 711
 712                                 hexdump(stderr, "Hnext", h.b, 16);
 713                                 hexdump(stderr, "Adata", c->mgm_partial_buffer.b, 16);
 714                                         /* Galois multiply Hi * Ai */
 715                                         gf128_mul_uint64(tmp.q, h.q, c->mgm_partial_buffer.q);
 716
 717                                         /* XOR to c->tag */
 718                                         grasshopper_plus128(&h, (grasshopper_w128_t *)c->tag, &tmp);
 719                                         grasshopper_copy128((grasshopper_w128_t *)c->tag, &h);
 720                                 hexdump(stderr, "Tag", c->tag, 16);
 721
 722                                         current_in += GRASSHOPPER_BLOCK_SIZE - rest_len;
 723                                         inl -= (GRASSHOPPER_BLOCK_SIZE - rest_len);
 724                                         n += GRASSHOPPER_BLOCK_SIZE - rest_len;
 725                                 }
 726                         }
 727
 728                         while (inl >= GRASSHOPPER_BLOCK_SIZE) {
 729         currentInputBlock = (grasshopper_w128_t *) current_in;
 730
 731         grasshopper_encrypt_block(&c->c.encrypt_round_keys, c->mgm_iv,
 732                                   &h, &c->c.buffer);
 733                                 inc_counter(c->mgm_iv->b, 8);
 734
 735                                 hexdump(stderr, "Hnext", h.b, 16);
 736                                 hexdump(stderr, "Adata", currentInputBlock->b, 16);
 737                                 /* Galois multiply */
 738                                 gf128_mul_uint64(tmp.q, h.q, currentInputBlock->q);
 739
 740                                 /* XOR to c->tag */
 741                                 grasshopper_plus128(&h, (grasshopper_w128_t *)c->tag, &tmp);
 742                                 grasshopper_copy128((grasshopper_w128_t *)c->tag, &h);
 743                                 hexdump(stderr, "Tag", c->tag, 16);
 744
 745                                 current_in += GRASSHOPPER_BLOCK_SIZE;
 746                                 inl -= GRASSHOPPER_BLOCK_SIZE;
 747                                 n += GRASSHOPPER_BLOCK_SIZE;
 748                         }
 749
 750                         if (inl > 0)
 751                         {
 752                                 memcpy(c->mgm_partial_buffer.b, current_in, inl);
 753                                 n += inl;
 754                         }
 755
 756                         EVP_CIPHER_CTX_set_num(ctx, n);
 757                         return 1;
 758                 }
 759
 760                 if (out == NULL && in != NULL && inl !=0 && c->mgm_state == mgm_main_data) {
 761                         GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_DO_MGM, GOST_R_BAD_ORDER);
 762                         return 0;
 763                 }
 764
 765                 if (out != NULL && c->mgm_state == mgm_associated_data) {
 766                         memset(c->mgm_partial_buffer.b+rest_len, 0, GRASSHOPPER_BLOCK_SIZE - rest_len);
 767
 768                         grasshopper_encrypt_block(&c->c.encrypt_round_keys, c->mgm_iv,
 769                                         &h, &c->c.buffer);
 770                         inc_counter(c->mgm_iv->b, 8);
 771
 772                         hexdump(stderr, "Hnext", h.b, 16);
 773                         hexdump(stderr, "Padded Adata", c->mgm_partial_buffer.b, 16);
 774                         /* Galois multiply Hi * Ai */
 775                         gf128_mul_uint64(tmp.q, h.q, c->mgm_partial_buffer.q);
 776
 777                         /* XOR to c->tag */
 778                         grasshopper_plus128(&h, (grasshopper_w128_t *)c->tag, &tmp);
 779                         grasshopper_copy128((grasshopper_w128_t *)c->tag, &h);
 780                                 hexdump(stderr, "Tag", c->tag, 16);
 781
 782                         /* We finish processing associated data */
 783                         /* Pad rest of mgm_partial_buffer */
 784                         /* Process last block */
 785                         c->ad_length = n;
 786                         n = 0;
 787                         EVP_CIPHER_CTX_set_num(ctx, 0);
 788                         c->mgm_state = mgm_main_data;
 789
 790                         fprintf(stderr, "============= Deal with main data\n");
 791                 }
 792
 793 /* ======== Here we deal with main data =========== */
 794     if (n == 0) {
 795                         /* actual IV derived from nonce */
 796       grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer,
 797                                   &c->partial_buffer, &c->c.buffer);
 798                         memcpy(iv, c->partial_buffer.b, GRASSHOPPER_BLOCK_SIZE);
 799                         //hexdump(stderr, "Y1", iv, 16);
 800                 }
 801
 802     while (rest_len && inl) {
 803         *(current_out++) = *(current_in++) ^ c->partial_buffer.b[rest_len];
 804         --inl;
 805         n++;
 806                                 rest_len++;
 807                                 if (rest_len == GRASSHOPPER_BLOCK_SIZE)
 808                                 {
 809                                         rest_len = 0;
 810                                 }
 811     }
 812     EVP_CIPHER_CTX_set_num(ctx, n);
 813
 814     // full parts
 815     for (i = 0; i < blocks; i++) {
 816         currentInputBlock = (grasshopper_w128_t *) current_in;
 817         currentOutputBlock = (grasshopper_w128_t *) current_out;
 818         grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer,
 819                                   &c->partial_buffer, &c->c.buffer);
 820         grasshopper_plus128(&tmp, &c->partial_buffer, currentInputBlock);
 821         grasshopper_copy128(currentOutputBlock, &tmp);
 822                         //hexdump(stderr, "Ciphertext", currentOutputBlock->b, 16);
 823
 824                                 grasshopper_encrypt_block(&c->c.encrypt_round_keys, c->mgm_iv,
 825                                                         &h, &c->c.buffer);
 826                                 inc_counter(c->mgm_iv->b, 8);
 827                         hexdump(stderr, "Hnext", h.b, 16);
 828                         hexdump(stderr, "Ciphertext", currentOutputBlock->b, 16);
 829                                 /* Galois multiply Hi * Ai */
 830                                 gf128_mul_uint64(tmp.q, h.q, currentOutputBlock->q);
 831
 832                                 /* XOR to c->tag */
 833                                 grasshopper_plus128(&h, (grasshopper_w128_t *)c->tag, &tmp);
 834                                 grasshopper_copy128((grasshopper_w128_t *)c->tag, &h);
 835                                 hexdump(stderr, "Tag", c->tag, 16);
 836
 837         ctr128_inc(iv_buffer->b);
 838         current_in += GRASSHOPPER_BLOCK_SIZE;
 839         current_out += GRASSHOPPER_BLOCK_SIZE;
 840                                 n += GRASSHOPPER_BLOCK_SIZE;
 841     }
 842
 843     // last part
 844     lasted = inl - blocks * GRASSHOPPER_BLOCK_SIZE;
 845     if (lasted > 0) {
 846         currentInputBlock = (grasshopper_w128_t *) current_in;
 847         currentOutputBlock = (grasshopper_w128_t *) current_out;
 848         grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer,
 849                                   &c->partial_buffer, &c->c.buffer);
 850         for (i = 0; i < lasted; i++) {
 851             currentOutputBlock->b[i] =
 852                 c->partial_buffer.b[i] ^ currentInputBlock->b[i];
 853         }
 854                                 grasshopper_copy128(&c->partial_buffer, currentOutputBlock);
 855         EVP_CIPHER_CTX_set_num(ctx, n+i);
 856         ctr128_inc(iv_buffer->b);
 857     }
 858
 859                 /* Final step */
 860                 if (in == NULL && inl == 0)
 861                 {
 862                         unsigned char len_buf[16];
 863                         uint64_t a_len = 0, p_len = 0;
 864
 865                         if (rest_len != 0)
 866                         {
 867                                 memset(c->partial_buffer.b+rest_len, 0, GRASSHOPPER_BLOCK_SIZE - rest_len);
 868                                 grasshopper_encrypt_block(&c->c.encrypt_round_keys, c->mgm_iv,
 869                                                         &h, &c->c.buffer);
 870                                 inc_counter(c->mgm_iv->b, 8);
 871                         hexdump(stderr, "Hnext", h.b, 16);
 872                         hexdump(stderr, "Padded ciphertext", c->partial_buffer.b, 16);
 873                                 /* Galois multiply Hi * Ai */
 874                                 gf128_mul_uint64(tmp.q, h.q, c->partial_buffer.q);
 875
 876                                 /* XOR to c->tag */
 877                                 grasshopper_plus128(&h, (grasshopper_w128_t *)c->tag, &tmp);
 878                                 grasshopper_copy128((grasshopper_w128_t *)c->tag, &h);
 879                                 hexdump(stderr, "Tag", c->tag, 16);
 880                         }
 881
 882                         a_len = c->ad_length << 3;
 883                         p_len = (c->mgm_state == mgm_associated_data) ? 0 : n << 3;
 884
 885 #ifdef L_ENDIAN
 886                         a_len = bswap_64(a_len);
 887                         p_len = bswap_64(p_len);
 888 #endif
 889                         memset(len_buf, 0, 16);
 890
 891                         memcpy(len_buf, &a_len, sizeof(a_len));
 892                         memcpy(len_buf+sizeof(a_len), &p_len, sizeof(p_len));
 893                         grasshopper_encrypt_block(&c->c.encrypt_round_keys, c->mgm_iv,
 894                                                         &h, &c->c.buffer);
 895
 896                         hexdump(stderr, "Hlast", h.b, 16);
 897                         hexdump(stderr, "Lenbuf", len_buf, 16);
 898                         /* Galois multiply Hi * Ai */
 899                         gf128_mul_uint64(tmp.q, h.q, (uint64_t *)len_buf);
 900
 901                         /* XOR to c->tag */
 902                         grasshopper_plus128(&h, (grasshopper_w128_t *)c->tag, &tmp);
 903                         grasshopper_copy128((grasshopper_w128_t *)c->tag, &h);
 904                                 hexdump(stderr, "Tag", c->tag, 16);
 905
 906                         /* Final tag calculation */
 907       grasshopper_encrypt_block(&c->c.encrypt_round_keys, (grasshopper_w128_t *)c->tag,
 908                                   (grasshopper_w128_t *)c->final_tag, &c->c.buffer);
 909                 }
 910
 911     return 1;
 912 }
 913
 914 /*
 915  * Fixed 128-bit IV implementation make shift regiser redundant.
 916  */
 917 static void gost_grasshopper_cnt_next(gost_grasshopper_cipher_ctx_ofb * ctx,
 918                                       grasshopper_w128_t * iv,
 919                                       grasshopper_w128_t * buf)
 920 {
 921     memcpy(&ctx->buffer1, iv, 16);
 922     grasshopper_encrypt_block(&ctx->c.encrypt_round_keys, &ctx->buffer1,
 923                               buf, &ctx->c.buffer);
 924     memcpy(iv, buf, 16);
 925 }
 926
 927 int gost_grasshopper_cipher_do_ofb(EVP_CIPHER_CTX *ctx, unsigned char *out,
 928                                    const unsigned char *in, size_t inl)
 929 {
 930     gost_grasshopper_cipher_ctx_ofb *c = (gost_grasshopper_cipher_ctx_ofb *)
 931         EVP_CIPHER_CTX_get_cipher_data(ctx);
 932     const unsigned char *in_ptr = in;
 933     unsigned char *out_ptr = out;
 934     unsigned char *buf = EVP_CIPHER_CTX_buf_noconst(ctx);
 935     unsigned char *iv = EVP_CIPHER_CTX_iv_noconst(ctx);
 936     int num = EVP_CIPHER_CTX_num(ctx);
 937     size_t i = 0;
 938     size_t j;
 939
 940     /* process partial block if any */
 941     if (num > 0) {
 942         for (j = (size_t)num, i = 0; j < GRASSHOPPER_BLOCK_SIZE && i < inl;
 943              j++, i++, in_ptr++, out_ptr++) {
 944             *out_ptr = buf[j] ^ (*in_ptr);
 945         }
 946         if (j == GRASSHOPPER_BLOCK_SIZE) {
 947             EVP_CIPHER_CTX_set_num(ctx, 0);
 948         } else {
 949             EVP_CIPHER_CTX_set_num(ctx, (int)j);
 950             return 1;
 951         }
 952     }
 953
 954     for (; i + GRASSHOPPER_BLOCK_SIZE <
 955          inl;
 956          i += GRASSHOPPER_BLOCK_SIZE, in_ptr +=
 957          GRASSHOPPER_BLOCK_SIZE, out_ptr += GRASSHOPPER_BLOCK_SIZE) {
 958         /*
 959          * block cipher current iv
 960          */
 961         /* Encrypt */
 962         gost_grasshopper_cnt_next(c, (grasshopper_w128_t *) iv,
 963                                   (grasshopper_w128_t *) buf);
 964
 965         /*
 966          * xor next block of input text with it and output it
 967          */
 968         /*
 969          * output this block
 970          */
 971         for (j = 0; j < GRASSHOPPER_BLOCK_SIZE; j++) {
 972             out_ptr[j] = buf[j] ^ in_ptr[j];
 973         }
 974     }
 975
 976     /* Process rest of buffer */
 977     if (i < inl) {
 978         gost_grasshopper_cnt_next(c, (grasshopper_w128_t *) iv,
 979                                   (grasshopper_w128_t *) buf);
 980         for (j = 0; i < inl; j++, i++) {
 981             out_ptr[j] = buf[j] ^ in_ptr[j];
 982         }
 983         EVP_CIPHER_CTX_set_num(ctx, (int)j);
 984     } else {
 985         EVP_CIPHER_CTX_set_num(ctx, 0);
 986     }
 987
 988     return 1;
 989 }
 990
 991 int gost_grasshopper_cipher_do_cfb(EVP_CIPHER_CTX *ctx, unsigned char *out,
 992                                    const unsigned char *in, size_t inl)
 993 {
 994     gost_grasshopper_cipher_ctx *c =
 995         (gost_grasshopper_cipher_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
 996     const unsigned char *in_ptr = in;
 997     unsigned char *out_ptr = out;
 998     unsigned char *buf = EVP_CIPHER_CTX_buf_noconst(ctx);
 999     unsigned char *iv = EVP_CIPHER_CTX_iv_noconst(ctx);
1000     bool encrypting = (bool) EVP_CIPHER_CTX_encrypting(ctx);
1001     int num = EVP_CIPHER_CTX_num(ctx);
1002     size_t i = 0;
1003     size_t j = 0;
1004
1005     /* process partial block if any */
1006     if (num > 0) {
1007         for (j = (size_t)num, i = 0; j < GRASSHOPPER_BLOCK_SIZE && i < inl;
1008              j++, i++, in_ptr++, out_ptr++) {
1009             if (!encrypting) {
1010                 buf[j + GRASSHOPPER_BLOCK_SIZE] = *in_ptr;
1011             }
1012             *out_ptr = buf[j] ^ (*in_ptr);
1013             if (encrypting) {
1014                 buf[j + GRASSHOPPER_BLOCK_SIZE] = *out_ptr;
1015             }
1016         }
1017         if (j == GRASSHOPPER_BLOCK_SIZE) {
1018             memcpy(iv, buf + GRASSHOPPER_BLOCK_SIZE, GRASSHOPPER_BLOCK_SIZE);
1019             EVP_CIPHER_CTX_set_num(ctx, 0);
1020         } else {
1021             EVP_CIPHER_CTX_set_num(ctx, (int)j);
1022             return 1;
1023         }
1024     }
1025
1026     for (; i + GRASSHOPPER_BLOCK_SIZE <
1027          inl;
1028          i += GRASSHOPPER_BLOCK_SIZE, in_ptr +=
1029          GRASSHOPPER_BLOCK_SIZE, out_ptr += GRASSHOPPER_BLOCK_SIZE) {
1030         /*
1031          * block cipher current iv
1032          */
1033         grasshopper_encrypt_block(&c->encrypt_round_keys,
1034                                   (grasshopper_w128_t *) iv,
1035                                   (grasshopper_w128_t *) buf, &c->buffer);
1036         /*
1037          * xor next block of input text with it and output it
1038          */
1039         /*
1040          * output this block
1041          */
1042         if (!encrypting) {
1043             memcpy(iv, in_ptr, GRASSHOPPER_BLOCK_SIZE);
1044         }
1045         for (j = 0; j < GRASSHOPPER_BLOCK_SIZE; j++) {
1046             out_ptr[j] = buf[j] ^ in_ptr[j];
1047         }
1048         /* Encrypt */
1049         /* Next iv is next block of cipher text */
1050         if (encrypting) {
1051             memcpy(iv, out_ptr, GRASSHOPPER_BLOCK_SIZE);
1052         }
1053     }
1054
1055     /* Process rest of buffer */
1056     if (i < inl) {
1057         grasshopper_encrypt_block(&c->encrypt_round_keys,
1058                                   (grasshopper_w128_t *) iv,
1059                                   (grasshopper_w128_t *) buf, &c->buffer);
1060         if (!encrypting) {
1061             memcpy(buf + GRASSHOPPER_BLOCK_SIZE, in_ptr, inl - i);
1062         }
1063         for (j = 0; i < inl; j++, i++) {
1064             out_ptr[j] = buf[j] ^ in_ptr[j];
1065         }
1066         EVP_CIPHER_CTX_set_num(ctx, (int)j);
1067         if (encrypting) {
1068             memcpy(buf + GRASSHOPPER_BLOCK_SIZE, out_ptr, j);
1069         }
1070     } else {
1071         EVP_CIPHER_CTX_set_num(ctx, 0);
1072     }
1073
1074     return 1;
1075 }
1076
1077 int gost_grasshopper_cipher_cleanup(EVP_CIPHER_CTX *ctx)
1078 {
1079     gost_grasshopper_cipher_ctx *c =
1080         (gost_grasshopper_cipher_ctx *) EVP_CIPHER_CTX_get_cipher_data(ctx);
1081
1082     if (!c)
1083         return 1;
1084
1085     struct GRASSHOPPER_CIPHER_PARAMS *params = &gost_cipher_params[c->type];
1086
1087     gost_grasshopper_cipher_destroy(c);
1088     if (params->destroy_cipher != NULL) {
1089         params->destroy_cipher(c);
1090     }
1091
1092     EVP_CIPHER_CTX_set_app_data(ctx, NULL);
1093
1094     return 1;
1095 }
1096
1097 int gost_grasshopper_set_asn1_parameters(EVP_CIPHER_CTX *ctx, ASN1_TYPE *params)
1098 {
1099     int len = 0;
1100     unsigned char *buf = NULL;
1101     ASN1_OCTET_STRING *os = NULL;
1102
1103     os = ASN1_OCTET_STRING_new();
1104
1105     if (!os || !ASN1_OCTET_STRING_set(os, buf, len)) {
1106         OPENSSL_free(buf);
1107         GOSTerr(GOST_F_GOST_GRASSHOPPER_SET_ASN1_PARAMETERS,
1108                 ERR_R_MALLOC_FAILURE);
1109         return 0;
1110     }
1111     OPENSSL_free(buf);
1112
1113     ASN1_TYPE_set(params, V_ASN1_SEQUENCE, os);
1114     return 1;
1115 }
1116
1117 GRASSHOPPER_INLINE int gost_grasshopper_get_asn1_parameters(EVP_CIPHER_CTX
1118                                                             *ctx, ASN1_TYPE
1119                                                             *params)
1120 {
1121     int ret = -1;
1122
1123     if (ASN1_TYPE_get(params) != V_ASN1_SEQUENCE) {
1124         return ret;
1125     }
1126
1127     return 1;
1128 }
1129
1130 int gost_grasshopper_cipher_ctl(EVP_CIPHER_CTX *ctx, int type, int arg,
1131                                 void *ptr)
1132 {
1133     switch (type) {
1134     case EVP_CTRL_RAND_KEY:{
1135             if (RAND_bytes
1136                 ((unsigned char *)ptr, EVP_CIPHER_CTX_key_length(ctx)) <= 0) {
1137                 GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_CTL, GOST_R_RNG_ERROR);
1138                 return -1;
1139             }
1140             break;
1141         }
1142     case EVP_CTRL_KEY_MESH:{
1143             gost_grasshopper_cipher_ctx_ctr *c =
1144                 EVP_CIPHER_CTX_get_cipher_data(ctx);
1145             if (c->c.type != GRASSHOPPER_CIPHER_CTRACPKM || !arg
1146                 || (arg % GRASSHOPPER_BLOCK_SIZE))
1147                 return -1;
1148             c->section_size = arg;
1149             break;
1150         }
1151 #ifdef EVP_CTRL_TLS1_2_TLSTREE
1152     case EVP_CTRL_TLS1_2_TLSTREE:
1153         {
1154           unsigned char newkey[32];
1155           int mode = EVP_CIPHER_CTX_mode(ctx);
1156           static const unsigned char zeroseq[8];
1157           gost_grasshopper_cipher_ctx_ctr *ctr_ctx = NULL;
1158           gost_grasshopper_cipher_ctx *c = NULL;
1159
1160           unsigned char adjusted_iv[16];
1161           unsigned char seq[8];
1162           int j, carry;
1163           if (mode != EVP_CIPH_CTR_MODE)
1164             return -1;
1165
1166           ctr_ctx = (gost_grasshopper_cipher_ctx_ctr *)
1167             EVP_CIPHER_CTX_get_cipher_data(ctx);
1168           c = &(ctr_ctx->c);
1169
1170           memcpy(seq, ptr, 8);
1171           if (EVP_CIPHER_CTX_encrypting(ctx)) {
1172             /*
1173              * OpenSSL increments seq after mac calculation.
1174              * As we have Mac-Then-Encrypt, we need decrement it here on encryption
1175              * to derive the key correctly.
1176              * */
1177             if (memcmp(seq, zeroseq, 8) != 0)
1178             {
1179               for(j=7; j>=0; j--)
1180               {
1181                 if (seq[j] != 0) {seq[j]--; break;}
1182                 else seq[j]  = 0xFF;
1183               }
1184             }
1185           }
1186           if (gost_tlstree(NID_grasshopper_cbc, c->master_key.k.b, newkey,
1187                 (const unsigned char *)seq) > 0) {
1188             memset(adjusted_iv, 0, 16);
1189             memcpy(adjusted_iv, EVP_CIPHER_CTX_original_iv(ctx), 8);
1190             for(j=7,carry=0; j>=0; j--)
1191             {
1192               int adj_byte = adjusted_iv[j]+seq[j]+carry;
1193               carry = (adj_byte > 255) ? 1 : 0;
1194               adjusted_iv[j] = adj_byte & 0xFF;
1195             }
1196             EVP_CIPHER_CTX_set_num(ctx, 0);
1197             memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), adjusted_iv, 16);
1198
1199             gost_grasshopper_cipher_key(c, newkey);
1200             return 1;
1201           }
1202         }
1203         return -1;
1204 #endif
1205                 case EVP_CTRL_AEAD_GET_TAG:
1206                 case EVP_CTRL_AEAD_SET_TAG:
1207                 {
1208           gost_grasshopper_cipher_ctx_mgm *mgm_ctx = NULL;
1209           gost_grasshopper_cipher_ctx *c = NULL;
1210                                         int taglen = arg;
1211                                         unsigned char* tag = ptr;
1212
1213           mgm_ctx = (gost_grasshopper_cipher_ctx_mgm *)
1214             EVP_CIPHER_CTX_get_cipher_data(ctx);
1215                                         c = (gost_grasshopper_cipher_ctx *)mgm_ctx;
1216
1217                                         if (c->type != GRASSHOPPER_CIPHER_MGM)
1218                                                 return -1;
1219
1220                                         if (taglen > 16) {
1221                                                 GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_CTL, GOST_R_INVALID_TAG_LENGTH);
1222                                                 return -1;
1223                                         }
1224
1225                                         if (type == EVP_CTRL_AEAD_GET_TAG)
1226                                                 memcpy(tag, mgm_ctx->final_tag, taglen);
1227                                         else
1228                                                 memcpy(mgm_ctx->final_tag, tag, taglen);
1229
1230                                         return 1;
1231                 }
1232     default:
1233         GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_CTL,
1234                 GOST_R_UNSUPPORTED_CIPHER_CTL_COMMAND);
1235         return -1;
1236     }
1237     return 1;
1238 }
1239
1240 GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper_create(int
1241                                                               cipher_type, int
1242                                                               block_size)
1243 {
1244     return EVP_CIPHER_meth_new(cipher_type, block_size /* block_size */ ,
1245                                GRASSHOPPER_KEY_SIZE /* key_size */ );
1246 }
1247
1248 const int cipher_gost_grasshopper_setup(EVP_CIPHER *cipher, uint8_t mode,
1249                                         int iv_size, bool padding, int extra_flags)
1250 {
1251     return EVP_CIPHER_meth_set_iv_length(cipher, iv_size)
1252         && EVP_CIPHER_meth_set_flags(cipher,
1253                                      (unsigned long)(mode |
1254                                                      ((!padding) ?
1255                                                       EVP_CIPH_NO_PADDING :
1256                                                       0) | ((iv_size >
1257                                                              0) ?
1258                                                             EVP_CIPH_CUSTOM_IV
1259                                                             : 0) |
1260                                                      EVP_CIPH_RAND_KEY |
1261                                                      EVP_CIPH_ALWAYS_CALL_INIT | extra_flags)
1262         )
1263         && EVP_CIPHER_meth_set_cleanup(cipher, gost_grasshopper_cipher_cleanup)
1264         && EVP_CIPHER_meth_set_set_asn1_params(cipher,
1265                                                gost_grasshopper_set_asn1_parameters)
1266         && EVP_CIPHER_meth_set_get_asn1_params(cipher,
1267                                                gost_grasshopper_get_asn1_parameters)
1268         && EVP_CIPHER_meth_set_ctrl(cipher, gost_grasshopper_cipher_ctl)
1269         && EVP_CIPHER_meth_set_do_cipher(cipher, gost_grasshopper_cipher_do);
1270 }
1271
1272 const GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper(uint8_t mode,
1273                                                              uint8_t num)
1274 {
1275     EVP_CIPHER **cipher;
1276     struct GRASSHOPPER_CIPHER_PARAMS *params;
1277
1278     cipher = &gost_grasshopper_ciphers[num];
1279
1280     if (*cipher == NULL) {
1281         params = &gost_cipher_params[num];
1282
1283         int nid = params->nid;
1284         grasshopper_init_cipher_func init_cipher = params->init_cipher;
1285         int block_size = params->block_size;
1286         int ctx_size = params->ctx_size;
1287         int iv_size = params->iv_size;
1288         bool padding = params->padding;
1289
1290                                 int extra_flags = (num == GRASSHOPPER_CIPHER_MGM) ?
1291                                         EVP_CIPH_FLAG_CUSTOM_CIPHER | EVP_CIPH_FLAG_AEAD_CIPHER : 0;
1292
1293         *cipher = cipher_gost_grasshopper_create(nid, block_size);
1294         if (*cipher == NULL) {
1295             return NULL;
1296         }
1297
1298         if (!cipher_gost_grasshopper_setup(*cipher, mode, iv_size, padding, extra_flags)
1299             || !EVP_CIPHER_meth_set_init(*cipher, init_cipher)
1300             || !EVP_CIPHER_meth_set_impl_ctx_size(*cipher, ctx_size)) {
1301             EVP_CIPHER_meth_free(*cipher);
1302             *cipher = NULL;
1303         }
1304     }
1305
1306     return *cipher;
1307 }
1308
1309 const GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper_ecb()
1310 {
1311     return cipher_gost_grasshopper(EVP_CIPH_ECB_MODE, GRASSHOPPER_CIPHER_ECB);
1312 }
1313
1314 const GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper_cbc()
1315 {
1316     return cipher_gost_grasshopper(EVP_CIPH_CBC_MODE, GRASSHOPPER_CIPHER_CBC);
1317 }
1318
1319 const GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper_ofb()
1320 {
1321     return cipher_gost_grasshopper(EVP_CIPH_OFB_MODE, GRASSHOPPER_CIPHER_OFB);
1322 }
1323
1324 const GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper_cfb()
1325 {
1326     return cipher_gost_grasshopper(EVP_CIPH_CFB_MODE, GRASSHOPPER_CIPHER_CFB);
1327 }
1328
1329 const GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper_ctr()
1330 {
1331     return cipher_gost_grasshopper(EVP_CIPH_CTR_MODE, GRASSHOPPER_CIPHER_CTR);
1332 }
1333
1334 const GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper_ctracpkm()
1335 {
1336     return cipher_gost_grasshopper(EVP_CIPH_CTR_MODE,
1337                                    GRASSHOPPER_CIPHER_CTRACPKM);
1338 }
1339
1340 const GRASSHOPPER_INLINE EVP_CIPHER *cipher_gost_grasshopper_mgm()
1341 {
1342 #ifndef NID_kuznyechik_mgm
1343                 return NULL;
1344 #else
1345     return cipher_gost_grasshopper(EVP_CIPH_CTR_MODE, GRASSHOPPER_CIPHER_MGM);
1346 #endif
1347 }
1348
1349 void cipher_gost_grasshopper_destroy(void)
1350 {
1351     EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_ECB]);
1352     gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_ECB] = NULL;
1353     EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CBC]);
1354     gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CBC] = NULL;
1355     EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_OFB]);
1356     gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_OFB] = NULL;
1357     EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CFB]);
1358     gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CFB] = NULL;
1359     EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CTR]);
1360     gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CTR] = NULL;
1361     EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CTRACPKM]);
1362     gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CTRACPKM] = NULL;
1363     EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_MGM]);
1364     gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_MGM] = NULL;
1365 }