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  *
   7  * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
   8  * and Nettle, by Niels Möller.
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 2 of the License, or (at your option)
  13  * any later version.
  14  *
  15  */
  16 #ifndef _LINUX_CRYPTO_H
  17 #define _LINUX_CRYPTO_H
  18
  19 #include <linux/config.h>
  20 #include <linux/module.h>
  21 #include <linux/kernel.h>
  22 #include <linux/types.h>
  23 #include <linux/list.h>
  24 #include <linux/string.h>
  25 #include <asm/page.h>
  26
  27 /*
  28  * Algorithm masks and types.
  29  */
  30 #define CRYPTO_ALG_TYPE_MASK            0x000000ff
  31 #define CRYPTO_ALG_TYPE_CIPHER          0x00000001
  32 #define CRYPTO_ALG_TYPE_DIGEST          0x00000002
  33 #define CRYPTO_ALG_TYPE_COMPRESS        0x00000004
  34
  35 /*
  36  * Transform masks and values (for crt_flags).
  37  */
  38 #define CRYPTO_TFM_MODE_MASK            0x000000ff
  39 #define CRYPTO_TFM_REQ_MASK             0x000fff00
  40 #define CRYPTO_TFM_RES_MASK             0xfff00000
  41
  42 #define CRYPTO_TFM_MODE_ECB             0x00000001
  43 #define CRYPTO_TFM_MODE_CBC             0x00000002
  44 #define CRYPTO_TFM_MODE_CFB             0x00000004
  45 #define CRYPTO_TFM_MODE_CTR             0x00000008
  46
  47 #define CRYPTO_TFM_REQ_WEAK_KEY         0x00000100
  48 #define CRYPTO_TFM_RES_WEAK_KEY         0x00100000
  49 #define CRYPTO_TFM_RES_BAD_KEY_LEN      0x00200000
  50 #define CRYPTO_TFM_RES_BAD_KEY_SCHED    0x00400000
  51 #define CRYPTO_TFM_RES_BAD_BLOCK_LEN    0x00800000
  52 #define CRYPTO_TFM_RES_BAD_FLAGS        0x01000000
  53
  54 /*
  55  * Miscellaneous stuff.
  56  */
  57 #define CRYPTO_UNSPEC                   0
  58 #define CRYPTO_MAX_ALG_NAME             64
  59
  60 #define CRYPTO_DIR_ENCRYPT              1
  61 #define CRYPTO_DIR_DECRYPT              0
  62
  63 struct scatterlist;
  64
  65 /*
  66  * Algorithms: modular crypto algorithm implementations, managed
  67  * via crypto_register_alg() and crypto_unregister_alg().
  68  */
  69 struct cipher_alg {
  70         unsigned int cia_min_keysize;
  71         unsigned int cia_max_keysize;
  72         int (*cia_setkey)(void *ctx, const u8 *key,
  73                           unsigned int keylen, u32 *flags);
  74         void (*cia_encrypt)(void *ctx, u8 *dst, const u8 *src);
  75         void (*cia_decrypt)(void *ctx, u8 *dst, const u8 *src);
  76 };
  77
  78 struct digest_alg {
  79         unsigned int dia_digestsize;
  80         void (*dia_init)(void *ctx);
  81         void (*dia_update)(void *ctx, const u8 *data, unsigned int len);
  82         void (*dia_final)(void *ctx, u8 *out);
  83         int (*dia_setkey)(void *ctx, const u8 *key,
  84                           unsigned int keylen, u32 *flags);
  85 };
  86
  87 struct compress_alg {
  88         int (*coa_init)(void *ctx);
  89         void (*coa_exit)(void *ctx);
  90         int (*coa_compress)(void *ctx, const u8 *src, unsigned int slen,
  91                             u8 *dst, unsigned int *dlen);
  92         int (*coa_decompress)(void *ctx, const u8 *src, unsigned int slen,
  93                               u8 *dst, unsigned int *dlen);
  94 };
  95
  96 #define cra_cipher      cra_u.cipher
  97 #define cra_digest      cra_u.digest
  98 #define cra_compress    cra_u.compress
  99
 100 struct crypto_alg {
 101         struct list_head cra_list;
 102         u32 cra_flags;
 103         unsigned int cra_blocksize;
 104         unsigned int cra_ctxsize;
 105         const char cra_name[CRYPTO_MAX_ALG_NAME];
 106
 107         union {
 108                 struct cipher_alg cipher;
 109                 struct digest_alg digest;
 110                 struct compress_alg compress;
 111         } cra_u;
 112
 113         struct module *cra_module;
 114 };
 115
 116 /*
 117  * Algorithm registration interface.
 118  */
 119 int crypto_register_alg(struct crypto_alg *alg);
 120 int crypto_unregister_alg(struct crypto_alg *alg);
 121
 122 /*
 123  * Algorithm query interface.
 124  */
 125 #ifdef CONFIG_CRYPTO
 126 int crypto_alg_available(const char *name, u32 flags);
 127 #else
 128 static inline int crypto_alg_available(const char *name, u32 flags)
 129 {
 130         return 0;
 131 }
 132 #endif
 133
 134 /*
 135  * Transforms: user-instantiated objects which encapsulate algorithms
 136  * and core processing logic.  Managed via crypto_alloc_tfm() and
 137  * crypto_free_tfm(), as well as the various helpers below.
 138  */
 139 struct crypto_tfm;
 140
 141 struct cipher_tfm {
 142         void *cit_iv;
 143         unsigned int cit_ivsize;
 144         u32 cit_mode;
 145         int (*cit_setkey)(struct crypto_tfm *tfm,
 146                           const u8 *key, unsigned int keylen);
 147         int (*cit_encrypt)(struct crypto_tfm *tfm,
 148                            struct scatterlist *dst,
 149                            struct scatterlist *src,
 150                            unsigned int nbytes);
 151         int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
 152                               struct scatterlist *dst,
 153                               struct scatterlist *src,
 154                               unsigned int nbytes, u8 *iv);
 155         int (*cit_decrypt)(struct crypto_tfm *tfm,
 156                            struct scatterlist *dst,
 157                            struct scatterlist *src,
 158                            unsigned int nbytes);
 159         int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
 160                            struct scatterlist *dst,
 161                            struct scatterlist *src,
 162                            unsigned int nbytes, u8 *iv);
 163         void (*cit_xor_block)(u8 *dst, const u8 *src);
 164 };
 165
 166 struct digest_tfm {
 167         void (*dit_init)(struct crypto_tfm *tfm);
 168         void (*dit_update)(struct crypto_tfm *tfm,
 169                            struct scatterlist *sg, unsigned int nsg);
 170         void (*dit_update_kernel)(struct crypto_tfm *tfm,
 171                                   const void *data, size_t count);
 172         void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
 173         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 174                            unsigned int nsg, u8 *out);
 175         int (*dit_setkey)(struct crypto_tfm *tfm,
 176                           const u8 *key, unsigned int keylen);
 177 #ifdef CONFIG_CRYPTO_HMAC
 178         void *dit_hmac_block;
 179 #endif
 180 };
 181
 182 struct compress_tfm {
 183         int (*cot_compress)(struct crypto_tfm *tfm,
 184                             const u8 *src, unsigned int slen,
 185                             u8 *dst, unsigned int *dlen);
 186         int (*cot_decompress)(struct crypto_tfm *tfm,
 187                               const u8 *src, unsigned int slen,
 188                               u8 *dst, unsigned int *dlen);
 189 };
 190
 191 #define crt_cipher      crt_u.cipher
 192 #define crt_digest      crt_u.digest
 193 #define crt_compress    crt_u.compress
 194
 195 struct crypto_tfm {
 196
 197         u32 crt_flags;
 198
 199         union {
 200                 struct cipher_tfm cipher;
 201                 struct digest_tfm digest;
 202                 struct compress_tfm compress;
 203         } crt_u;
 204
 205         struct crypto_alg *__crt_alg;
 206 };
 207
 208 /*
 209  * Transform user interface.
 210  */
 211
 212 /*
 213  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 214  * If that fails and the kernel supports dynamically loadable modules, it
 215  * will then attempt to load a module of the same name or alias.  A refcount
 216  * is grabbed on the algorithm which is then associated with the new transform.
 217  *
 218  * crypto_alloc_tfm2() is similar, but allows module loading to be suppressed.
 219  *
 220  * crypto_free_tfm() frees up the transform and any associated resources,
 221  * then drops the refcount on the associated algorithm.
 222  */
 223 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 224 struct crypto_tfm *crypto_alloc_tfm2(const char *alg_name, u32 tfm_flags,
 225                                      int nomodload);
 226 void crypto_free_tfm(struct crypto_tfm *tfm);
 227
 228 /*
 229  * Transform helpers which query the underlying algorithm.
 230  */
 231 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 232 {
 233         return tfm->__crt_alg->cra_name;
 234 }
 235
 236 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 237 {
 238         return module_name(tfm->__crt_alg->cra_module);
 239 }
 240
 241 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 242 {
 243         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 244 }
 245
 246 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 247 {
 248         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 249         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 250 }
 251
 252 static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
 253 {
 254         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 255         return tfm->__crt_alg->cra_cipher.cia_max_keysize;
 256 }
 257
 258 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 259 {
 260         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 261         return tfm->crt_cipher.cit_ivsize;
 262 }
 263
 264 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 265 {
 266         return tfm->__crt_alg->cra_blocksize;
 267 }
 268
 269 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 270 {
 271         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 272         return tfm->__crt_alg->cra_digest.dia_digestsize;
 273 }
 274
 275 /*
 276  * API wrappers.
 277  */
 278 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 279 {
 280         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 281         tfm->crt_digest.dit_init(tfm);
 282 }
 283
 284 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 285                                         struct scatterlist *sg,
 286                                         unsigned int nsg)
 287 {
 288         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 289         tfm->crt_digest.dit_update(tfm, sg, nsg);
 290 }
 291
 292 static inline void crypto_digest_update_kernel(struct crypto_tfm *tfm,
 293                                                const void *data,
 294                                                size_t count)
 295 {
 296         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 297         tfm->crt_digest.dit_update_kernel(tfm, data, count);
 298 }
 299
 300 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 301 {
 302         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 303         tfm->crt_digest.dit_final(tfm, out);
 304 }
 305
 306 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 307                                         struct scatterlist *sg,
 308                                         unsigned int nsg, u8 *out)
 309 {
 310         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 311         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 312 }
 313
 314 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 315                                        const u8 *key, unsigned int keylen)
 316 {
 317         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 318         if (tfm->crt_digest.dit_setkey == NULL)
 319                 return -ENOSYS;
 320         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 321 }
 322
 323 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 324                                        const u8 *key, unsigned int keylen)
 325 {
 326         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 327         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 328 }
 329
 330 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 331                                         struct scatterlist *dst,
 332                                         struct scatterlist *src,
 333                                         unsigned int nbytes)
 334 {
 335         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 336         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 337 }
 338
 339 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 340                                            struct scatterlist *dst,
 341                                            struct scatterlist *src,
 342                                            unsigned int nbytes, u8 *iv)
 343 {
 344         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 345         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 346         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 347 }
 348
 349 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 350                                         struct scatterlist *dst,
 351                                         struct scatterlist *src,
 352                                         unsigned int nbytes)
 353 {
 354         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 355         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 356 }
 357
 358 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 359                                            struct scatterlist *dst,
 360                                            struct scatterlist *src,
 361                                            unsigned int nbytes, u8 *iv)
 362 {
 363         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 364         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 365         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 366 }
 367
 368 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 369                                         const u8 *src, unsigned int len)
 370 {
 371         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 372         memcpy(tfm->crt_cipher.cit_iv, src, len);
 373 }
 374
 375 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 376                                         u8 *dst, unsigned int len)
 377 {
 378         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 379         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 380 }
 381
 382 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 383                                        const u8 *src, unsigned int slen,
 384                                        u8 *dst, unsigned int *dlen)
 385 {
 386         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 387         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 388 }
 389
 390 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 391                                          const u8 *src, unsigned int slen,
 392                                          u8 *dst, unsigned int *dlen)
 393 {
 394         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 395         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 396 }
 397
 398 /*
 399  * HMAC support.
 400  */
 401 #ifdef CONFIG_CRYPTO_HMAC
 402 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 403 void crypto_hmac_update(struct crypto_tfm *tfm,
 404                         struct scatterlist *sg, unsigned int nsg);
 405 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 406                        unsigned int *keylen, u8 *out);
 407 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 408                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 409 #endif  /* CONFIG_CRYPTO_HMAC */
 410
 411 #endif  /* _LINUX_CRYPTO_H */
 412