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_final)(struct crypto_tfm *tfm, u8 *out);
 171         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 172                            unsigned int nsg, u8 *out);
 173         int (*dit_setkey)(struct crypto_tfm *tfm,
 174                           const u8 *key, unsigned int keylen);
 175 #ifdef CONFIG_CRYPTO_HMAC
 176         void *dit_hmac_block;
 177 #endif
 178 };
 179
 180 struct compress_tfm {
 181         int (*cot_compress)(struct crypto_tfm *tfm,
 182                             const u8 *src, unsigned int slen,
 183                             u8 *dst, unsigned int *dlen);
 184         int (*cot_decompress)(struct crypto_tfm *tfm,
 185                               const u8 *src, unsigned int slen,
 186                               u8 *dst, unsigned int *dlen);
 187 };
 188
 189 #define crt_cipher      crt_u.cipher
 190 #define crt_digest      crt_u.digest
 191 #define crt_compress    crt_u.compress
 192
 193 struct crypto_tfm {
 194
 195         u32 crt_flags;
 196
 197         union {
 198                 struct cipher_tfm cipher;
 199                 struct digest_tfm digest;
 200                 struct compress_tfm compress;
 201         } crt_u;
 202
 203         struct crypto_alg *__crt_alg;
 204 };
 205
 206 /*
 207  * Transform user interface.
 208  */
 209
 210 /*
 211  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 212  * If that fails and the kernel supports dynamically loadable modules, it
 213  * will then attempt to load a module of the same name or alias.  A refcount
 214  * is grabbed on the algorithm which is then associated with the new transform.
 215  *
 216  * crypto_free_tfm() frees up the transform and any associated resources,
 217  * then drops the refcount on the associated algorithm.
 218  */
 219 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 220 void crypto_free_tfm(struct crypto_tfm *tfm);
 221
 222 /*
 223  * Transform helpers which query the underlying algorithm.
 224  */
 225 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 226 {
 227         return tfm->__crt_alg->cra_name;
 228 }
 229
 230 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 231 {
 232         return module_name(tfm->__crt_alg->cra_module);
 233 }
 234
 235 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 236 {
 237         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 238 }
 239
 240 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 241 {
 242         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 243         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 244 }
 245
 246 static inline unsigned int crypto_tfm_alg_max_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_max_keysize;
 250 }
 251
 252 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 253 {
 254         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 255         return tfm->crt_cipher.cit_ivsize;
 256 }
 257
 258 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 259 {
 260         return tfm->__crt_alg->cra_blocksize;
 261 }
 262
 263 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 264 {
 265         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 266         return tfm->__crt_alg->cra_digest.dia_digestsize;
 267 }
 268
 269 /*
 270  * API wrappers.
 271  */
 272 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 273 {
 274         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 275         tfm->crt_digest.dit_init(tfm);
 276 }
 277
 278 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 279                                         struct scatterlist *sg,
 280                                         unsigned int nsg)
 281 {
 282         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 283         tfm->crt_digest.dit_update(tfm, sg, nsg);
 284 }
 285
 286 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 287 {
 288         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 289         tfm->crt_digest.dit_final(tfm, out);
 290 }
 291
 292 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 293                                         struct scatterlist *sg,
 294                                         unsigned int nsg, u8 *out)
 295 {
 296         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 297         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 298 }
 299
 300 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 301                                        const u8 *key, unsigned int keylen)
 302 {
 303         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 304         if (tfm->crt_digest.dit_setkey == NULL)
 305                 return -ENOSYS;
 306         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 307 }
 308
 309 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 310                                        const u8 *key, unsigned int keylen)
 311 {
 312         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 313         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 314 }
 315
 316 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 317                                         struct scatterlist *dst,
 318                                         struct scatterlist *src,
 319                                         unsigned int nbytes)
 320 {
 321         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 322         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 323 }
 324
 325 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 326                                            struct scatterlist *dst,
 327                                            struct scatterlist *src,
 328                                            unsigned int nbytes, u8 *iv)
 329 {
 330         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 331         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 332         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 333 }
 334
 335 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 336                                         struct scatterlist *dst,
 337                                         struct scatterlist *src,
 338                                         unsigned int nbytes)
 339 {
 340         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 341         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 342 }
 343
 344 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 345                                            struct scatterlist *dst,
 346                                            struct scatterlist *src,
 347                                            unsigned int nbytes, u8 *iv)
 348 {
 349         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 350         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 351         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 352 }
 353
 354 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 355                                         const u8 *src, unsigned int len)
 356 {
 357         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 358         memcpy(tfm->crt_cipher.cit_iv, src, len);
 359 }
 360
 361 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 362                                         u8 *dst, unsigned int len)
 363 {
 364         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 365         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 366 }
 367
 368 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 369                                        const u8 *src, unsigned int slen,
 370                                        u8 *dst, unsigned int *dlen)
 371 {
 372         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 373         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 374 }
 375
 376 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 377                                          const u8 *src, unsigned int slen,
 378                                          u8 *dst, unsigned int *dlen)
 379 {
 380         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 381         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 382 }
 383
 384 /*
 385  * HMAC support.
 386  */
 387 #ifdef CONFIG_CRYPTO_HMAC
 388 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 389 void crypto_hmac_update(struct crypto_tfm *tfm,
 390                         struct scatterlist *sg, unsigned int nsg);
 391 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 392                        unsigned int *keylen, u8 *out);
 393 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 394                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 395 #endif  /* CONFIG_CRYPTO_HMAC */
 396
 397 #endif  /* _LINUX_CRYPTO_H */
 398