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_final)(struct crypto_tfm *tfm, u8 *out);
 160         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 161                            unsigned int nsg, u8 *out);
 162         int (*dit_setkey)(struct crypto_tfm *tfm,
 163                           const u8 *key, unsigned int keylen);
 164 #ifdef CONFIG_CRYPTO_HMAC
 165         void *dit_hmac_block;
 166 #endif
 167 };
 168
 169 struct compress_tfm {
 170         int (*cot_compress)(struct crypto_tfm *tfm,
 171                             const u8 *src, unsigned int slen,
 172                             u8 *dst, unsigned int *dlen);
 173         int (*cot_decompress)(struct crypto_tfm *tfm,
 174                               const u8 *src, unsigned int slen,
 175                               u8 *dst, unsigned int *dlen);
 176 };
 177
 178 #define crt_cipher      crt_u.cipher
 179 #define crt_digest      crt_u.digest
 180 #define crt_compress    crt_u.compress
 181
 182 struct crypto_tfm {
 183
 184         u32 crt_flags;
 185
 186         union {
 187                 struct cipher_tfm cipher;
 188                 struct digest_tfm digest;
 189                 struct compress_tfm compress;
 190         } crt_u;
 191
 192         struct crypto_alg *__crt_alg;
 193 };
 194
 195 /*
 196  * Transform user interface.
 197  */
 198
 199 /*
 200  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 201  * If that fails and the kernel supports dynamically loadable modules, it
 202  * will then attempt to load a module of the same name or alias.  A refcount
 203  * is grabbed on the algorithm which is then associated with the new transform.
 204  *
 205  * crypto_free_tfm() frees up the transform and any associated resources,
 206  * then drops the refcount on the associated algorithm.
 207  */
 208 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 209 void crypto_free_tfm(struct crypto_tfm *tfm);
 210
 211 /*
 212  * Transform helpers which query the underlying algorithm.
 213  */
 214 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 215 {
 216         return tfm->__crt_alg->cra_name;
 217 }
 218
 219 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 220 {
 221         return module_name(tfm->__crt_alg->cra_module);
 222 }
 223
 224 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 225 {
 226         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 227 }
 228
 229 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 230 {
 231         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 232         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 233 }
 234
 235 static inline unsigned int crypto_tfm_alg_max_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_max_keysize;
 239 }
 240
 241 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 242 {
 243         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 244         return tfm->crt_cipher.cit_ivsize;
 245 }
 246
 247 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 248 {
 249         return tfm->__crt_alg->cra_blocksize;
 250 }
 251
 252 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 253 {
 254         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 255         return tfm->__crt_alg->cra_digest.dia_digestsize;
 256 }
 257
 258 /*
 259  * API wrappers.
 260  */
 261 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 262 {
 263         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 264         tfm->crt_digest.dit_init(tfm);
 265 }
 266
 267 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 268                                         struct scatterlist *sg,
 269                                         unsigned int nsg)
 270 {
 271         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 272         tfm->crt_digest.dit_update(tfm, sg, nsg);
 273 }
 274
 275 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 276 {
 277         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 278         tfm->crt_digest.dit_final(tfm, out);
 279 }
 280
 281 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 282                                         struct scatterlist *sg,
 283                                         unsigned int nsg, u8 *out)
 284 {
 285         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 286         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 287 }
 288
 289 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 290                                        const u8 *key, unsigned int keylen)
 291 {
 292         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 293         if (tfm->crt_digest.dit_setkey == NULL)
 294                 return -ENOSYS;
 295         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 296 }
 297
 298 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 299                                        const u8 *key, unsigned int keylen)
 300 {
 301         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 302         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 303 }
 304
 305 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 306                                         struct scatterlist *dst,
 307                                         struct scatterlist *src,
 308                                         unsigned int nbytes)
 309 {
 310         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 311         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 312 }
 313
 314 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 315                                            struct scatterlist *dst,
 316                                            struct scatterlist *src,
 317                                            unsigned int nbytes, u8 *iv)
 318 {
 319         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 320         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 321         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 322 }
 323
 324 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 325                                         struct scatterlist *dst,
 326                                         struct scatterlist *src,
 327                                         unsigned int nbytes)
 328 {
 329         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 330         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 331 }
 332
 333 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 334                                            struct scatterlist *dst,
 335                                            struct scatterlist *src,
 336                                            unsigned int nbytes, u8 *iv)
 337 {
 338         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 339         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 340         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 341 }
 342
 343 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 344                                         const u8 *src, unsigned int len)
 345 {
 346         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 347         memcpy(tfm->crt_cipher.cit_iv, src, len);
 348 }
 349
 350 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 351                                         u8 *dst, unsigned int len)
 352 {
 353         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 354         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 355 }
 356
 357 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 358                                        const u8 *src, unsigned int slen,
 359                                        u8 *dst, unsigned int *dlen)
 360 {
 361         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 362         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 363 }
 364
 365 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 366                                          const u8 *src, unsigned int slen,
 367                                          u8 *dst, unsigned int *dlen)
 368 {
 369         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 370         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 371 }
 372
 373 /*
 374  * HMAC support.
 375  */
 376 #ifdef CONFIG_CRYPTO_HMAC
 377 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 378 void crypto_hmac_update(struct crypto_tfm *tfm,
 379                         struct scatterlist *sg, unsigned int nsg);
 380 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 381                        unsigned int *keylen, u8 *out);
 382 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 383                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 384 #endif  /* CONFIG_CRYPTO_HMAC */
 385
 386 #endif  /* _LINUX_CRYPTO_H */
 387