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 };
  80
  81 struct compress_alg {
  82         int (*coa_init)(void *ctx);
  83         void (*coa_exit)(void *ctx);
  84         int (*coa_compress)(void *ctx, const u8 *src, unsigned int slen,
  85                             u8 *dst, unsigned int *dlen);
  86         int (*coa_decompress)(void *ctx, const u8 *src, unsigned int slen,
  87                               u8 *dst, unsigned int *dlen);
  88 };
  89
  90 #define cra_cipher      cra_u.cipher
  91 #define cra_digest      cra_u.digest
  92 #define cra_compress    cra_u.compress
  93
  94 struct crypto_alg {
  95         struct list_head cra_list;
  96         u32 cra_flags;
  97         unsigned int cra_blocksize;
  98         unsigned int cra_ctxsize;
  99         const char cra_name[CRYPTO_MAX_ALG_NAME];
 100
 101         union {
 102                 struct cipher_alg cipher;
 103                 struct digest_alg digest;
 104                 struct compress_alg compress;
 105         } cra_u;
 106
 107         struct module *cra_module;
 108 };
 109
 110 /*
 111  * Algorithm registration interface.
 112  */
 113 int crypto_register_alg(struct crypto_alg *alg);
 114 int crypto_unregister_alg(struct crypto_alg *alg);
 115
 116 /*
 117  * Algorithm query interface.
 118  */
 119 int crypto_alg_available(const char *name, u32 flags);
 120
 121 /*
 122  * Transforms: user-instantiated objects which encapsulate algorithms
 123  * and core processing logic.  Managed via crypto_alloc_tfm() and
 124  * crypto_free_tfm(), as well as the various helpers below.
 125  */
 126 struct crypto_tfm;
 127
 128 struct cipher_tfm {
 129         void *cit_iv;
 130         unsigned int cit_ivsize;
 131         u32 cit_mode;
 132         int (*cit_setkey)(struct crypto_tfm *tfm,
 133                           const u8 *key, unsigned int keylen);
 134         int (*cit_encrypt)(struct crypto_tfm *tfm,
 135                            struct scatterlist *dst,
 136                            struct scatterlist *src,
 137                            unsigned int nbytes);
 138         int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
 139                               struct scatterlist *dst,
 140                               struct scatterlist *src,
 141                               unsigned int nbytes, u8 *iv);
 142         int (*cit_decrypt)(struct crypto_tfm *tfm,
 143                            struct scatterlist *dst,
 144                            struct scatterlist *src,
 145                            unsigned int nbytes);
 146         int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
 147                            struct scatterlist *dst,
 148                            struct scatterlist *src,
 149                            unsigned int nbytes, u8 *iv);
 150         void (*cit_xor_block)(u8 *dst, const u8 *src);
 151 };
 152
 153 struct digest_tfm {
 154         void (*dit_init)(struct crypto_tfm *tfm);
 155         void (*dit_update)(struct crypto_tfm *tfm,
 156                            struct scatterlist *sg, unsigned int nsg);
 157         void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
 158         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 159                            unsigned int nsg, u8 *out);
 160 #ifdef CONFIG_CRYPTO_HMAC
 161         void *dit_hmac_block;
 162 #endif
 163 };
 164
 165 struct compress_tfm {
 166         int (*cot_compress)(struct crypto_tfm *tfm,
 167                             const u8 *src, unsigned int slen,
 168                             u8 *dst, unsigned int *dlen);
 169         int (*cot_decompress)(struct crypto_tfm *tfm,
 170                               const u8 *src, unsigned int slen,
 171                               u8 *dst, unsigned int *dlen);
 172 };
 173
 174 #define crt_cipher      crt_u.cipher
 175 #define crt_digest      crt_u.digest
 176 #define crt_compress    crt_u.compress
 177
 178 struct crypto_tfm {
 179
 180         u32 crt_flags;
 181
 182         union {
 183                 struct cipher_tfm cipher;
 184                 struct digest_tfm digest;
 185                 struct compress_tfm compress;
 186         } crt_u;
 187
 188         struct crypto_alg *__crt_alg;
 189 };
 190
 191 /*
 192  * Transform user interface.
 193  */
 194
 195 /*
 196  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 197  * If that fails and the kernel supports dynamically loadable modules, it
 198  * will then attempt to load a module of the same name or alias.  A refcount
 199  * is grabbed on the algorithm which is then associated with the new transform.
 200  *
 201  * crypto_free_tfm() frees up the transform and any associated resources,
 202  * then drops the refcount on the associated algorithm.
 203  */
 204 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 205 void crypto_free_tfm(struct crypto_tfm *tfm);
 206
 207 /*
 208  * Transform helpers which query the underlying algorithm.
 209  */
 210 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 211 {
 212         return tfm->__crt_alg->cra_name;
 213 }
 214
 215 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 216 {
 217         return module_name(tfm->__crt_alg->cra_module);
 218 }
 219
 220 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 221 {
 222         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 223 }
 224
 225 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 226 {
 227         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 228         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 229 }
 230
 231 static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
 232 {
 233         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 234         return tfm->__crt_alg->cra_cipher.cia_max_keysize;
 235 }
 236
 237 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 238 {
 239         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 240         return tfm->crt_cipher.cit_ivsize;
 241 }
 242
 243 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 244 {
 245         return tfm->__crt_alg->cra_blocksize;
 246 }
 247
 248 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 249 {
 250         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 251         return tfm->__crt_alg->cra_digest.dia_digestsize;
 252 }
 253
 254 /*
 255  * API wrappers.
 256  */
 257 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 258 {
 259         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 260         tfm->crt_digest.dit_init(tfm);
 261 }
 262
 263 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 264                                         struct scatterlist *sg,
 265                                         unsigned int nsg)
 266 {
 267         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 268         tfm->crt_digest.dit_update(tfm, sg, nsg);
 269 }
 270
 271 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 272 {
 273         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 274         tfm->crt_digest.dit_final(tfm, out);
 275 }
 276
 277 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 278                                         struct scatterlist *sg,
 279                                         unsigned int nsg, u8 *out)
 280 {
 281         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 282         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 283 }
 284
 285 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 286                                        const u8 *key, unsigned int keylen)
 287 {
 288         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 289         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 290 }
 291
 292 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 293                                         struct scatterlist *dst,
 294                                         struct scatterlist *src,
 295                                         unsigned int nbytes)
 296 {
 297         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 298         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 299 }
 300
 301 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 302                                            struct scatterlist *dst,
 303                                            struct scatterlist *src,
 304                                            unsigned int nbytes, u8 *iv)
 305 {
 306         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 307         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 308         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 309 }
 310
 311 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 312                                         struct scatterlist *dst,
 313                                         struct scatterlist *src,
 314                                         unsigned int nbytes)
 315 {
 316         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 317         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 318 }
 319
 320 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 321                                            struct scatterlist *dst,
 322                                            struct scatterlist *src,
 323                                            unsigned int nbytes, u8 *iv)
 324 {
 325         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 326         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 327         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 328 }
 329
 330 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 331                                         const u8 *src, unsigned int len)
 332 {
 333         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 334         memcpy(tfm->crt_cipher.cit_iv, src, len);
 335 }
 336
 337 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 338                                         u8 *dst, unsigned int len)
 339 {
 340         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 341         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 342 }
 343
 344 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 345                                        const u8 *src, unsigned int slen,
 346                                        u8 *dst, unsigned int *dlen)
 347 {
 348         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 349         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 350 }
 351
 352 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 353                                          const u8 *src, unsigned int slen,
 354                                          u8 *dst, unsigned int *dlen)
 355 {
 356         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 357         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 358 }
 359
 360 /*
 361  * HMAC support.
 362  */
 363 #ifdef CONFIG_CRYPTO_HMAC
 364 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 365 void crypto_hmac_update(struct crypto_tfm *tfm,
 366                         struct scatterlist *sg, unsigned int nsg);
 367 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 368                        unsigned int *keylen, u8 *out);
 369 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 370                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 371 #endif  /* CONFIG_CRYPTO_HMAC */
 372
 373 #endif  /* _LINUX_CRYPTO_H */
 374