arch/s390/crypto/des_s390.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * s390 implementation of the DES Cipher Algorithm.
   5  *
   6  * Copyright IBM Corp. 2003,2007
   7  * Author(s): Thomas Spatzier
   8  *            Jan Glauber (jan.glauber@de.ibm.com)
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  */
  16
  17 #include <linux/init.h>
  18 #include <linux/module.h>
  19 #include <linux/crypto.h>
  20 #include <crypto/algapi.h>
  21 #include <crypto/des.h>
  22
  23 #include "crypt_s390.h"
  24
  25 #define DES3_192_KEY_SIZE       (3 * DES_KEY_SIZE)
  26
  27 struct crypt_s390_des_ctx {
  28         u8 iv[DES_BLOCK_SIZE];
  29         u8 key[DES_KEY_SIZE];
  30 };
  31
  32 struct crypt_s390_des3_192_ctx {
  33         u8 iv[DES_BLOCK_SIZE];
  34         u8 key[DES3_192_KEY_SIZE];
  35 };
  36
  37 static int des_setkey(struct crypto_tfm *tfm, const u8 *key,
  38                       unsigned int keylen)
  39 {
  40         struct crypt_s390_des_ctx *dctx = crypto_tfm_ctx(tfm);
  41         u32 *flags = &tfm->crt_flags;
  42         u32 tmp[DES_EXPKEY_WORDS];
  43
  44         /* check for weak keys */
  45         if (!des_ekey(tmp, key) && (*flags & CRYPTO_TFM_REQ_WEAK_KEY)) {
  46                 *flags |= CRYPTO_TFM_RES_WEAK_KEY;
  47                 return -EINVAL;
  48         }
  49
  50         memcpy(dctx->key, key, keylen);
  51         return 0;
  52 }
  53
  54 static void des_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
  55 {
  56         struct crypt_s390_des_ctx *dctx = crypto_tfm_ctx(tfm);
  57
  58         crypt_s390_km(KM_DEA_ENCRYPT, dctx->key, out, in, DES_BLOCK_SIZE);
  59 }
  60
  61 static void des_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
  62 {
  63         struct crypt_s390_des_ctx *dctx = crypto_tfm_ctx(tfm);
  64
  65         crypt_s390_km(KM_DEA_DECRYPT, dctx->key, out, in, DES_BLOCK_SIZE);
  66 }
  67
  68 static struct crypto_alg des_alg = {
  69         .cra_name               =       "des",
  70         .cra_driver_name        =       "des-s390",
  71         .cra_priority           =       CRYPT_S390_PRIORITY,
  72         .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
  73         .cra_blocksize          =       DES_BLOCK_SIZE,
  74         .cra_ctxsize            =       sizeof(struct crypt_s390_des_ctx),
  75         .cra_module             =       THIS_MODULE,
  76         .cra_list               =       LIST_HEAD_INIT(des_alg.cra_list),
  77         .cra_u                  =       {
  78                 .cipher = {
  79                         .cia_min_keysize        =       DES_KEY_SIZE,
  80                         .cia_max_keysize        =       DES_KEY_SIZE,
  81                         .cia_setkey             =       des_setkey,
  82                         .cia_encrypt            =       des_encrypt,
  83                         .cia_decrypt            =       des_decrypt,
  84                 }
  85         }
  86 };
  87
  88 static int ecb_desall_crypt(struct blkcipher_desc *desc, long func,
  89                             void *param, struct blkcipher_walk *walk)
  90 {
  91         int ret = blkcipher_walk_virt(desc, walk);
  92         unsigned int nbytes;
  93
  94         while ((nbytes = walk->nbytes)) {
  95                 /* only use complete blocks */
  96                 unsigned int n = nbytes & ~(DES_BLOCK_SIZE - 1);
  97                 u8 *out = walk->dst.virt.addr;
  98                 u8 *in = walk->src.virt.addr;
  99
 100                 ret = crypt_s390_km(func, param, out, in, n);
 101                 BUG_ON((ret < 0) || (ret != n));
 102
 103                 nbytes &= DES_BLOCK_SIZE - 1;
 104                 ret = blkcipher_walk_done(desc, walk, nbytes);
 105         }
 106
 107         return ret;
 108 }
 109
 110 static int cbc_desall_crypt(struct blkcipher_desc *desc, long func,
 111                             void *param, struct blkcipher_walk *walk)
 112 {
 113         int ret = blkcipher_walk_virt(desc, walk);
 114         unsigned int nbytes = walk->nbytes;
 115
 116         if (!nbytes)
 117                 goto out;
 118
 119         memcpy(param, walk->iv, DES_BLOCK_SIZE);
 120         do {
 121                 /* only use complete blocks */
 122                 unsigned int n = nbytes & ~(DES_BLOCK_SIZE - 1);
 123                 u8 *out = walk->dst.virt.addr;
 124                 u8 *in = walk->src.virt.addr;
 125
 126                 ret = crypt_s390_kmc(func, param, out, in, n);
 127                 BUG_ON((ret < 0) || (ret != n));
 128
 129                 nbytes &= DES_BLOCK_SIZE - 1;
 130                 ret = blkcipher_walk_done(desc, walk, nbytes);
 131         } while ((nbytes = walk->nbytes));
 132         memcpy(walk->iv, param, DES_BLOCK_SIZE);
 133
 134 out:
 135         return ret;
 136 }
 137
 138 static int ecb_des_encrypt(struct blkcipher_desc *desc,
 139                            struct scatterlist *dst, struct scatterlist *src,
 140                            unsigned int nbytes)
 141 {
 142         struct crypt_s390_des_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
 143         struct blkcipher_walk walk;
 144
 145         blkcipher_walk_init(&walk, dst, src, nbytes);
 146         return ecb_desall_crypt(desc, KM_DEA_ENCRYPT, sctx->key, &walk);
 147 }
 148
 149 static int ecb_des_decrypt(struct blkcipher_desc *desc,
 150                            struct scatterlist *dst, struct scatterlist *src,
 151                            unsigned int nbytes)
 152 {
 153         struct crypt_s390_des_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
 154         struct blkcipher_walk walk;
 155
 156         blkcipher_walk_init(&walk, dst, src, nbytes);
 157         return ecb_desall_crypt(desc, KM_DEA_DECRYPT, sctx->key, &walk);
 158 }
 159
 160 static struct crypto_alg ecb_des_alg = {
 161         .cra_name               =       "ecb(des)",
 162         .cra_driver_name        =       "ecb-des-s390",
 163         .cra_priority           =       CRYPT_S390_COMPOSITE_PRIORITY,
 164         .cra_flags              =       CRYPTO_ALG_TYPE_BLKCIPHER,
 165         .cra_blocksize          =       DES_BLOCK_SIZE,
 166         .cra_ctxsize            =       sizeof(struct crypt_s390_des_ctx),
 167         .cra_type               =       &crypto_blkcipher_type,
 168         .cra_module             =       THIS_MODULE,
 169         .cra_list               =       LIST_HEAD_INIT(ecb_des_alg.cra_list),
 170         .cra_u                  =       {
 171                 .blkcipher = {
 172                         .min_keysize            =       DES_KEY_SIZE,
 173                         .max_keysize            =       DES_KEY_SIZE,
 174                         .setkey                 =       des_setkey,
 175                         .encrypt                =       ecb_des_encrypt,
 176                         .decrypt                =       ecb_des_decrypt,
 177                 }
 178         }
 179 };
 180
 181 static int cbc_des_encrypt(struct blkcipher_desc *desc,
 182                            struct scatterlist *dst, struct scatterlist *src,
 183                            unsigned int nbytes)
 184 {
 185         struct crypt_s390_des_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
 186         struct blkcipher_walk walk;
 187
 188         blkcipher_walk_init(&walk, dst, src, nbytes);
 189         return cbc_desall_crypt(desc, KMC_DEA_ENCRYPT, sctx->iv, &walk);
 190 }
 191
 192 static int cbc_des_decrypt(struct blkcipher_desc *desc,
 193                            struct scatterlist *dst, struct scatterlist *src,
 194                            unsigned int nbytes)
 195 {
 196         struct crypt_s390_des_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
 197         struct blkcipher_walk walk;
 198
 199         blkcipher_walk_init(&walk, dst, src, nbytes);
 200         return cbc_desall_crypt(desc, KMC_DEA_DECRYPT, sctx->iv, &walk);
 201 }
 202
 203 static struct crypto_alg cbc_des_alg = {
 204         .cra_name               =       "cbc(des)",
 205         .cra_driver_name        =       "cbc-des-s390",
 206         .cra_priority           =       CRYPT_S390_COMPOSITE_PRIORITY,
 207         .cra_flags              =       CRYPTO_ALG_TYPE_BLKCIPHER,
 208         .cra_blocksize          =       DES_BLOCK_SIZE,
 209         .cra_ctxsize            =       sizeof(struct crypt_s390_des_ctx),
 210         .cra_type               =       &crypto_blkcipher_type,
 211         .cra_module             =       THIS_MODULE,
 212         .cra_list               =       LIST_HEAD_INIT(cbc_des_alg.cra_list),
 213         .cra_u                  =       {
 214                 .blkcipher = {
 215                         .min_keysize            =       DES_KEY_SIZE,
 216                         .max_keysize            =       DES_KEY_SIZE,
 217                         .ivsize                 =       DES_BLOCK_SIZE,
 218                         .setkey                 =       des_setkey,
 219                         .encrypt                =       cbc_des_encrypt,
 220                         .decrypt                =       cbc_des_decrypt,
 221                 }
 222         }
 223 };
 224
 225 /*
 226  * RFC2451:
 227  *
 228  *   For DES-EDE3, there is no known need to reject weak or
 229  *   complementation keys.  Any weakness is obviated by the use of
 230  *   multiple keys.
 231  *
 232  *   However, if the first two or last two independent 64-bit keys are
 233  *   equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
 234  *   same as DES.  Implementers MUST reject keys that exhibit this
 235  *   property.
 236  *
 237  */
 238 static int des3_192_setkey(struct crypto_tfm *tfm, const u8 *key,
 239                            unsigned int keylen)
 240 {
 241         struct crypt_s390_des3_192_ctx *dctx = crypto_tfm_ctx(tfm);
 242         u32 *flags = &tfm->crt_flags;
 243
 244         if (!(memcmp(key, &key[DES_KEY_SIZE], DES_KEY_SIZE) &&
 245             memcmp(&key[DES_KEY_SIZE], &key[DES_KEY_SIZE * 2],
 246                    DES_KEY_SIZE)) &&
 247             (*flags & CRYPTO_TFM_REQ_WEAK_KEY)) {
 248                 *flags |= CRYPTO_TFM_RES_WEAK_KEY;
 249                 return -EINVAL;
 250         }
 251         memcpy(dctx->key, key, keylen);
 252         return 0;
 253 }
 254
 255 static void des3_192_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
 256 {
 257         struct crypt_s390_des3_192_ctx *dctx = crypto_tfm_ctx(tfm);
 258
 259         crypt_s390_km(KM_TDEA_192_ENCRYPT, dctx->key, dst, (void*)src,
 260                       DES_BLOCK_SIZE);
 261 }
 262
 263 static void des3_192_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
 264 {
 265         struct crypt_s390_des3_192_ctx *dctx = crypto_tfm_ctx(tfm);
 266
 267         crypt_s390_km(KM_TDEA_192_DECRYPT, dctx->key, dst, (void*)src,
 268                       DES_BLOCK_SIZE);
 269 }
 270
 271 static struct crypto_alg des3_192_alg = {
 272         .cra_name               =       "des3_ede",
 273         .cra_driver_name        =       "des3_ede-s390",
 274         .cra_priority           =       CRYPT_S390_PRIORITY,
 275         .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
 276         .cra_blocksize          =       DES_BLOCK_SIZE,
 277         .cra_ctxsize            =       sizeof(struct crypt_s390_des3_192_ctx),
 278         .cra_module             =       THIS_MODULE,
 279         .cra_list               =       LIST_HEAD_INIT(des3_192_alg.cra_list),
 280         .cra_u                  =       {
 281                 .cipher = {
 282                         .cia_min_keysize        =       DES3_192_KEY_SIZE,
 283                         .cia_max_keysize        =       DES3_192_KEY_SIZE,
 284                         .cia_setkey             =       des3_192_setkey,
 285                         .cia_encrypt            =       des3_192_encrypt,
 286                         .cia_decrypt            =       des3_192_decrypt,
 287                 }
 288         }
 289 };
 290
 291 static int ecb_des3_192_encrypt(struct blkcipher_desc *desc,
 292                                 struct scatterlist *dst,
 293                                 struct scatterlist *src, unsigned int nbytes)
 294 {
 295         struct crypt_s390_des3_192_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
 296         struct blkcipher_walk walk;
 297
 298         blkcipher_walk_init(&walk, dst, src, nbytes);
 299         return ecb_desall_crypt(desc, KM_TDEA_192_ENCRYPT, sctx->key, &walk);
 300 }
 301
 302 static int ecb_des3_192_decrypt(struct blkcipher_desc *desc,
 303                                 struct scatterlist *dst,
 304                                 struct scatterlist *src, unsigned int nbytes)
 305 {
 306         struct crypt_s390_des3_192_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
 307         struct blkcipher_walk walk;
 308
 309         blkcipher_walk_init(&walk, dst, src, nbytes);
 310         return ecb_desall_crypt(desc, KM_TDEA_192_DECRYPT, sctx->key, &walk);
 311 }
 312
 313 static struct crypto_alg ecb_des3_192_alg = {
 314         .cra_name               =       "ecb(des3_ede)",
 315         .cra_driver_name        =       "ecb-des3_ede-s390",
 316         .cra_priority           =       CRYPT_S390_COMPOSITE_PRIORITY,
 317         .cra_flags              =       CRYPTO_ALG_TYPE_BLKCIPHER,
 318         .cra_blocksize          =       DES_BLOCK_SIZE,
 319         .cra_ctxsize            =       sizeof(struct crypt_s390_des3_192_ctx),
 320         .cra_type               =       &crypto_blkcipher_type,
 321         .cra_module             =       THIS_MODULE,
 322         .cra_list               =       LIST_HEAD_INIT(
 323                                                 ecb_des3_192_alg.cra_list),
 324         .cra_u                  =       {
 325                 .blkcipher = {
 326                         .min_keysize            =       DES3_192_KEY_SIZE,
 327                         .max_keysize            =       DES3_192_KEY_SIZE,
 328                         .setkey                 =       des3_192_setkey,
 329                         .encrypt                =       ecb_des3_192_encrypt,
 330                         .decrypt                =       ecb_des3_192_decrypt,
 331                 }
 332         }
 333 };
 334
 335 static int cbc_des3_192_encrypt(struct blkcipher_desc *desc,
 336                                 struct scatterlist *dst,
 337                                 struct scatterlist *src, unsigned int nbytes)
 338 {
 339         struct crypt_s390_des3_192_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
 340         struct blkcipher_walk walk;
 341
 342         blkcipher_walk_init(&walk, dst, src, nbytes);
 343         return cbc_desall_crypt(desc, KMC_TDEA_192_ENCRYPT, sctx->iv, &walk);
 344 }
 345
 346 static int cbc_des3_192_decrypt(struct blkcipher_desc *desc,
 347                                 struct scatterlist *dst,
 348                                 struct scatterlist *src, unsigned int nbytes)
 349 {
 350         struct crypt_s390_des3_192_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
 351         struct blkcipher_walk walk;
 352
 353         blkcipher_walk_init(&walk, dst, src, nbytes);
 354         return cbc_desall_crypt(desc, KMC_TDEA_192_DECRYPT, sctx->iv, &walk);
 355 }
 356
 357 static struct crypto_alg cbc_des3_192_alg = {
 358         .cra_name               =       "cbc(des3_ede)",
 359         .cra_driver_name        =       "cbc-des3_ede-s390",
 360         .cra_priority           =       CRYPT_S390_COMPOSITE_PRIORITY,
 361         .cra_flags              =       CRYPTO_ALG_TYPE_BLKCIPHER,
 362         .cra_blocksize          =       DES_BLOCK_SIZE,
 363         .cra_ctxsize            =       sizeof(struct crypt_s390_des3_192_ctx),
 364         .cra_type               =       &crypto_blkcipher_type,
 365         .cra_module             =       THIS_MODULE,
 366         .cra_list               =       LIST_HEAD_INIT(
 367                                                 cbc_des3_192_alg.cra_list),
 368         .cra_u                  =       {
 369                 .blkcipher = {
 370                         .min_keysize            =       DES3_192_KEY_SIZE,
 371                         .max_keysize            =       DES3_192_KEY_SIZE,
 372                         .ivsize                 =       DES_BLOCK_SIZE,
 373                         .setkey                 =       des3_192_setkey,
 374                         .encrypt                =       cbc_des3_192_encrypt,
 375                         .decrypt                =       cbc_des3_192_decrypt,
 376                 }
 377         }
 378 };
 379
 380 static int des_s390_init(void)
 381 {
 382         int ret;
 383
 384         if (!crypt_s390_func_available(KM_DEA_ENCRYPT) ||
 385             !crypt_s390_func_available(KM_TDEA_192_ENCRYPT))
 386                 return -EOPNOTSUPP;
 387
 388         ret = crypto_register_alg(&des_alg);
 389         if (ret)
 390                 goto des_err;
 391         ret = crypto_register_alg(&ecb_des_alg);
 392         if (ret)
 393                 goto ecb_des_err;
 394         ret = crypto_register_alg(&cbc_des_alg);
 395         if (ret)
 396                 goto cbc_des_err;
 397         ret = crypto_register_alg(&des3_192_alg);
 398         if (ret)
 399                 goto des3_192_err;
 400         ret = crypto_register_alg(&ecb_des3_192_alg);
 401         if (ret)
 402                 goto ecb_des3_192_err;
 403         ret = crypto_register_alg(&cbc_des3_192_alg);
 404         if (ret)
 405                 goto cbc_des3_192_err;
 406 out:
 407         return ret;
 408
 409 cbc_des3_192_err:
 410         crypto_unregister_alg(&ecb_des3_192_alg);
 411 ecb_des3_192_err:
 412         crypto_unregister_alg(&des3_192_alg);
 413 des3_192_err:
 414         crypto_unregister_alg(&cbc_des_alg);
 415 cbc_des_err:
 416         crypto_unregister_alg(&ecb_des_alg);
 417 ecb_des_err:
 418         crypto_unregister_alg(&des_alg);
 419 des_err:
 420         goto out;
 421 }
 422
 423 static void __exit des_s390_exit(void)
 424 {
 425         crypto_unregister_alg(&cbc_des3_192_alg);
 426         crypto_unregister_alg(&ecb_des3_192_alg);
 427         crypto_unregister_alg(&des3_192_alg);
 428         crypto_unregister_alg(&cbc_des_alg);
 429         crypto_unregister_alg(&ecb_des_alg);
 430         crypto_unregister_alg(&des_alg);
 431 }
 432
 433 module_init(des_s390_init);
 434 module_exit(des_s390_exit);
 435
 436 MODULE_ALIAS("des");
 437 MODULE_ALIAS("des3_ede");
 438
 439 MODULE_LICENSE("GPL");
 440 MODULE_DESCRIPTION("DES & Triple DES EDE Cipher Algorithms");