include/linux/crypto.h

   1 /*
   2  * Scatterlist Cryptographic API.
   3  *
   4  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
   5  * Copyright (c) 2002 David S. Miller (davem@redhat.com)
   6  * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
   7  *
   8  * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
   9  * and Nettle, by Niels Möller.
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU General Public License as published by the Free
  13  * Software Foundation; either version 2 of the License, or (at your option)
  14  * any later version.
  15  *
  16  */
  17 #ifndef _LINUX_CRYPTO_H
  18 #define _LINUX_CRYPTO_H
  19
  20 #include <asm/atomic.h>
  21 #include <linux/module.h>
  22 #include <linux/kernel.h>
  23 #include <linux/types.h>
  24 #include <linux/list.h>
  25 #include <linux/slab.h>
  26 #include <linux/string.h>
  27 #include <linux/uaccess.h>
  28
  29 /*
  30  * Algorithm masks and types.
  31  */
  32 #define CRYPTO_ALG_TYPE_MASK            0x0000000f
  33 #define CRYPTO_ALG_TYPE_CIPHER          0x00000001
  34 #define CRYPTO_ALG_TYPE_DIGEST          0x00000002
  35 #define CRYPTO_ALG_TYPE_COMPRESS        0x00000004
  36
  37 #define CRYPTO_ALG_LARVAL               0x00000010
  38 #define CRYPTO_ALG_DEAD                 0x00000020
  39 #define CRYPTO_ALG_DYING                0x00000040
  40
  41 /*
  42  * Transform masks and values (for crt_flags).
  43  */
  44 #define CRYPTO_TFM_MODE_MASK            0x000000ff
  45 #define CRYPTO_TFM_REQ_MASK             0x000fff00
  46 #define CRYPTO_TFM_RES_MASK             0xfff00000
  47
  48 #define CRYPTO_TFM_MODE_ECB             0x00000001
  49 #define CRYPTO_TFM_MODE_CBC             0x00000002
  50 #define CRYPTO_TFM_MODE_CFB             0x00000004
  51 #define CRYPTO_TFM_MODE_CTR             0x00000008
  52
  53 #define CRYPTO_TFM_REQ_WEAK_KEY         0x00000100
  54 #define CRYPTO_TFM_REQ_MAY_SLEEP        0x00000200
  55 #define CRYPTO_TFM_RES_WEAK_KEY         0x00100000
  56 #define CRYPTO_TFM_RES_BAD_KEY_LEN      0x00200000
  57 #define CRYPTO_TFM_RES_BAD_KEY_SCHED    0x00400000
  58 #define CRYPTO_TFM_RES_BAD_BLOCK_LEN    0x00800000
  59 #define CRYPTO_TFM_RES_BAD_FLAGS        0x01000000
  60
  61 /*
  62  * Miscellaneous stuff.
  63  */
  64 #define CRYPTO_UNSPEC                   0
  65 #define CRYPTO_MAX_ALG_NAME             64
  66
  67 #define CRYPTO_DIR_ENCRYPT              1
  68 #define CRYPTO_DIR_DECRYPT              0
  69
  70 /*
  71  * The macro CRYPTO_MINALIGN_ATTR (along with the void * type in the actual
  72  * declaration) is used to ensure that the crypto_tfm context structure is
  73  * aligned correctly for the given architecture so that there are no alignment
  74  * faults for C data types.  In particular, this is required on platforms such
  75  * as arm where pointers are 32-bit aligned but there are data types such as
  76  * u64 which require 64-bit alignment.
  77  */
  78 #if defined(ARCH_KMALLOC_MINALIGN)
  79 #define CRYPTO_MINALIGN ARCH_KMALLOC_MINALIGN
  80 #elif defined(ARCH_SLAB_MINALIGN)
  81 #define CRYPTO_MINALIGN ARCH_SLAB_MINALIGN
  82 #endif
  83
  84 #ifdef CRYPTO_MINALIGN
  85 #define CRYPTO_MINALIGN_ATTR __attribute__ ((__aligned__(CRYPTO_MINALIGN)))
  86 #else
  87 #define CRYPTO_MINALIGN_ATTR
  88 #endif
  89
  90 struct scatterlist;
  91 struct crypto_tfm;
  92
  93 struct cipher_desc {
  94         struct crypto_tfm *tfm;
  95         void (*crfn)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
  96         unsigned int (*prfn)(const struct cipher_desc *desc, u8 *dst,
  97                              const u8 *src, unsigned int nbytes);
  98         void *info;
  99 };
 100
 101 /*
 102  * Algorithms: modular crypto algorithm implementations, managed
 103  * via crypto_register_alg() and crypto_unregister_alg().
 104  */
 105 struct cipher_alg {
 106         unsigned int cia_min_keysize;
 107         unsigned int cia_max_keysize;
 108         int (*cia_setkey)(struct crypto_tfm *tfm, const u8 *key,
 109                           unsigned int keylen);
 110         void (*cia_encrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
 111         void (*cia_decrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
 112
 113         unsigned int (*cia_encrypt_ecb)(const struct cipher_desc *desc,
 114                                         u8 *dst, const u8 *src,
 115                                         unsigned int nbytes);
 116         unsigned int (*cia_decrypt_ecb)(const struct cipher_desc *desc,
 117                                         u8 *dst, const u8 *src,
 118                                         unsigned int nbytes);
 119         unsigned int (*cia_encrypt_cbc)(const struct cipher_desc *desc,
 120                                         u8 *dst, const u8 *src,
 121                                         unsigned int nbytes);
 122         unsigned int (*cia_decrypt_cbc)(const struct cipher_desc *desc,
 123                                         u8 *dst, const u8 *src,
 124                                         unsigned int nbytes);
 125 };
 126
 127 struct digest_alg {
 128         unsigned int dia_digestsize;
 129         void (*dia_init)(struct crypto_tfm *tfm);
 130         void (*dia_update)(struct crypto_tfm *tfm, const u8 *data,
 131                            unsigned int len);
 132         void (*dia_final)(struct crypto_tfm *tfm, u8 *out);
 133         int (*dia_setkey)(struct crypto_tfm *tfm, const u8 *key,
 134                           unsigned int keylen);
 135 };
 136
 137 struct compress_alg {
 138         int (*coa_compress)(struct crypto_tfm *tfm, const u8 *src,
 139                             unsigned int slen, u8 *dst, unsigned int *dlen);
 140         int (*coa_decompress)(struct crypto_tfm *tfm, const u8 *src,
 141                               unsigned int slen, u8 *dst, unsigned int *dlen);
 142 };
 143
 144 #define cra_cipher      cra_u.cipher
 145 #define cra_digest      cra_u.digest
 146 #define cra_compress    cra_u.compress
 147
 148 struct crypto_alg {
 149         struct list_head cra_list;
 150         struct list_head cra_users;
 151
 152         u32 cra_flags;
 153         unsigned int cra_blocksize;
 154         unsigned int cra_ctxsize;
 155         unsigned int cra_alignmask;
 156
 157         int cra_priority;
 158         atomic_t cra_refcnt;
 159
 160         char cra_name[CRYPTO_MAX_ALG_NAME];
 161         char cra_driver_name[CRYPTO_MAX_ALG_NAME];
 162
 163         union {
 164                 struct cipher_alg cipher;
 165                 struct digest_alg digest;
 166                 struct compress_alg compress;
 167         } cra_u;
 168
 169         int (*cra_init)(struct crypto_tfm *tfm);
 170         void (*cra_exit)(struct crypto_tfm *tfm);
 171         void (*cra_destroy)(struct crypto_alg *alg);
 172
 173         struct module *cra_module;
 174 };
 175
 176 /*
 177  * Algorithm registration interface.
 178  */
 179 int crypto_register_alg(struct crypto_alg *alg);
 180 int crypto_unregister_alg(struct crypto_alg *alg);
 181
 182 /*
 183  * Algorithm query interface.
 184  */
 185 #ifdef CONFIG_CRYPTO
 186 int crypto_alg_available(const char *name, u32 flags);
 187 #else
 188 static inline int crypto_alg_available(const char *name, u32 flags)
 189 {
 190         return 0;
 191 }
 192 #endif
 193
 194 /*
 195  * Transforms: user-instantiated objects which encapsulate algorithms
 196  * and core processing logic.  Managed via crypto_alloc_tfm() and
 197  * crypto_free_tfm(), as well as the various helpers below.
 198  */
 199
 200 struct cipher_tfm {
 201         void *cit_iv;
 202         unsigned int cit_ivsize;
 203         u32 cit_mode;
 204         int (*cit_setkey)(struct crypto_tfm *tfm,
 205                           const u8 *key, unsigned int keylen);
 206         int (*cit_encrypt)(struct crypto_tfm *tfm,
 207                            struct scatterlist *dst,
 208                            struct scatterlist *src,
 209                            unsigned int nbytes);
 210         int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
 211                               struct scatterlist *dst,
 212                               struct scatterlist *src,
 213                               unsigned int nbytes, u8 *iv);
 214         int (*cit_decrypt)(struct crypto_tfm *tfm,
 215                            struct scatterlist *dst,
 216                            struct scatterlist *src,
 217                            unsigned int nbytes);
 218         int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
 219                            struct scatterlist *dst,
 220                            struct scatterlist *src,
 221                            unsigned int nbytes, u8 *iv);
 222         void (*cit_xor_block)(u8 *dst, const u8 *src);
 223 };
 224
 225 struct digest_tfm {
 226         void (*dit_init)(struct crypto_tfm *tfm);
 227         void (*dit_update)(struct crypto_tfm *tfm,
 228                            struct scatterlist *sg, unsigned int nsg);
 229         void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
 230         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 231                            unsigned int nsg, u8 *out);
 232         int (*dit_setkey)(struct crypto_tfm *tfm,
 233                           const u8 *key, unsigned int keylen);
 234 #ifdef CONFIG_CRYPTO_HMAC
 235         void *dit_hmac_block;
 236 #endif
 237 };
 238
 239 struct compress_tfm {
 240         int (*cot_compress)(struct crypto_tfm *tfm,
 241                             const u8 *src, unsigned int slen,
 242                             u8 *dst, unsigned int *dlen);
 243         int (*cot_decompress)(struct crypto_tfm *tfm,
 244                               const u8 *src, unsigned int slen,
 245                               u8 *dst, unsigned int *dlen);
 246 };
 247
 248 #define crt_cipher      crt_u.cipher
 249 #define crt_digest      crt_u.digest
 250 #define crt_compress    crt_u.compress
 251
 252 struct crypto_tfm {
 253
 254         u32 crt_flags;
 255
 256         union {
 257                 struct cipher_tfm cipher;
 258                 struct digest_tfm digest;
 259                 struct compress_tfm compress;
 260         } crt_u;
 261
 262         struct crypto_alg *__crt_alg;
 263
 264         void *__crt_ctx[] CRYPTO_MINALIGN_ATTR;
 265 };
 266
 267 enum {
 268         CRYPTOA_UNSPEC,
 269         CRYPTOA_ALG,
 270 };
 271
 272 struct crypto_attr_alg {
 273         char name[CRYPTO_MAX_ALG_NAME];
 274 };
 275
 276 /*
 277  * Transform user interface.
 278  */
 279
 280 /*
 281  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 282  * If that fails and the kernel supports dynamically loadable modules, it
 283  * will then attempt to load a module of the same name or alias.  A refcount
 284  * is grabbed on the algorithm which is then associated with the new transform.
 285  *
 286  * crypto_free_tfm() frees up the transform and any associated resources,
 287  * then drops the refcount on the associated algorithm.
 288  */
 289 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 290 void crypto_free_tfm(struct crypto_tfm *tfm);
 291
 292 /*
 293  * Transform helpers which query the underlying algorithm.
 294  */
 295 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 296 {
 297         return tfm->__crt_alg->cra_name;
 298 }
 299
 300 static inline const char *crypto_tfm_alg_driver_name(struct crypto_tfm *tfm)
 301 {
 302         return tfm->__crt_alg->cra_driver_name;
 303 }
 304
 305 static inline int crypto_tfm_alg_priority(struct crypto_tfm *tfm)
 306 {
 307         return tfm->__crt_alg->cra_priority;
 308 }
 309
 310 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 311 {
 312         return module_name(tfm->__crt_alg->cra_module);
 313 }
 314
 315 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 316 {
 317         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 318 }
 319
 320 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 321 {
 322         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 323         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 324 }
 325
 326 static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
 327 {
 328         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 329         return tfm->__crt_alg->cra_cipher.cia_max_keysize;
 330 }
 331
 332 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 333 {
 334         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 335         return tfm->crt_cipher.cit_ivsize;
 336 }
 337
 338 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 339 {
 340         return tfm->__crt_alg->cra_blocksize;
 341 }
 342
 343 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 344 {
 345         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 346         return tfm->__crt_alg->cra_digest.dia_digestsize;
 347 }
 348
 349 static inline unsigned int crypto_tfm_alg_alignmask(struct crypto_tfm *tfm)
 350 {
 351         return tfm->__crt_alg->cra_alignmask;
 352 }
 353
 354 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
 355 {
 356         return tfm->__crt_ctx;
 357 }
 358
 359 static inline unsigned int crypto_tfm_ctx_alignment(void)
 360 {
 361         struct crypto_tfm *tfm;
 362         return __alignof__(tfm->__crt_ctx);
 363 }
 364
 365 /*
 366  * API wrappers.
 367  */
 368 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 369 {
 370         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 371         tfm->crt_digest.dit_init(tfm);
 372 }
 373
 374 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 375                                         struct scatterlist *sg,
 376                                         unsigned int nsg)
 377 {
 378         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 379         tfm->crt_digest.dit_update(tfm, sg, nsg);
 380 }
 381
 382 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 383 {
 384         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 385         tfm->crt_digest.dit_final(tfm, out);
 386 }
 387
 388 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 389                                         struct scatterlist *sg,
 390                                         unsigned int nsg, u8 *out)
 391 {
 392         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 393         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 394 }
 395
 396 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 397                                        const u8 *key, unsigned int keylen)
 398 {
 399         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 400         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 401 }
 402
 403 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 404                                        const u8 *key, unsigned int keylen)
 405 {
 406         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 407         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 408 }
 409
 410 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 411                                         struct scatterlist *dst,
 412                                         struct scatterlist *src,
 413                                         unsigned int nbytes)
 414 {
 415         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 416         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 417 }
 418
 419 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 420                                            struct scatterlist *dst,
 421                                            struct scatterlist *src,
 422                                            unsigned int nbytes, u8 *iv)
 423 {
 424         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 425         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 426 }
 427
 428 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 429                                         struct scatterlist *dst,
 430                                         struct scatterlist *src,
 431                                         unsigned int nbytes)
 432 {
 433         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 434         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 435 }
 436
 437 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 438                                            struct scatterlist *dst,
 439                                            struct scatterlist *src,
 440                                            unsigned int nbytes, u8 *iv)
 441 {
 442         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 443         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 444 }
 445
 446 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 447                                         const u8 *src, unsigned int len)
 448 {
 449         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 450         memcpy(tfm->crt_cipher.cit_iv, src, len);
 451 }
 452
 453 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 454                                         u8 *dst, unsigned int len)
 455 {
 456         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 457         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 458 }
 459
 460 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 461                                        const u8 *src, unsigned int slen,
 462                                        u8 *dst, unsigned int *dlen)
 463 {
 464         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 465         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 466 }
 467
 468 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 469                                          const u8 *src, unsigned int slen,
 470                                          u8 *dst, unsigned int *dlen)
 471 {
 472         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 473         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 474 }
 475
 476 /*
 477  * HMAC support.
 478  */
 479 #ifdef CONFIG_CRYPTO_HMAC
 480 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 481 void crypto_hmac_update(struct crypto_tfm *tfm,
 482                         struct scatterlist *sg, unsigned int nsg);
 483 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 484                        unsigned int *keylen, u8 *out);
 485 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 486                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 487 #endif  /* CONFIG_CRYPTO_HMAC */
 488
 489 #endif  /* _LINUX_CRYPTO_H */
 490