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