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 struct crypto_tfm;
  65
  66 struct cipher_desc {
  67         struct crypto_tfm *tfm;
  68         void (*crfn)(void *ctx, u8 *dst, const u8 *src);
  69         unsigned int (*prfn)(const struct cipher_desc *desc, u8 *dst,
  70                              const u8 *src, unsigned int nbytes);
  71         void *info;
  72 };
  73
  74 /*
  75  * Algorithms: modular crypto algorithm implementations, managed
  76  * via crypto_register_alg() and crypto_unregister_alg().
  77  */
  78 struct cipher_alg {
  79         unsigned int cia_min_keysize;
  80         unsigned int cia_max_keysize;
  81         int (*cia_setkey)(void *ctx, const u8 *key,
  82                           unsigned int keylen, u32 *flags);
  83         void (*cia_encrypt)(void *ctx, u8 *dst, const u8 *src);
  84         void (*cia_decrypt)(void *ctx, u8 *dst, const u8 *src);
  85
  86         unsigned int (*cia_encrypt_ecb)(const struct cipher_desc *desc,
  87                                         u8 *dst, const u8 *src,
  88                                         unsigned int nbytes);
  89         unsigned int (*cia_decrypt_ecb)(const struct cipher_desc *desc,
  90                                         u8 *dst, const u8 *src,
  91                                         unsigned int nbytes);
  92         unsigned int (*cia_encrypt_cbc)(const struct cipher_desc *desc,
  93                                         u8 *dst, const u8 *src,
  94                                         unsigned int nbytes);
  95         unsigned int (*cia_decrypt_cbc)(const struct cipher_desc *desc,
  96                                         u8 *dst, const u8 *src,
  97                                         unsigned int nbytes);
  98 };
  99
 100 struct digest_alg {
 101         unsigned int dia_digestsize;
 102         void (*dia_init)(void *ctx);
 103         void (*dia_update)(void *ctx, const u8 *data, unsigned int len);
 104         void (*dia_final)(void *ctx, u8 *out);
 105         int (*dia_setkey)(void *ctx, const u8 *key,
 106                           unsigned int keylen, u32 *flags);
 107 };
 108
 109 struct compress_alg {
 110         int (*coa_init)(void *ctx);
 111         void (*coa_exit)(void *ctx);
 112         int (*coa_compress)(void *ctx, const u8 *src, unsigned int slen,
 113                             u8 *dst, unsigned int *dlen);
 114         int (*coa_decompress)(void *ctx, const u8 *src, unsigned int slen,
 115                               u8 *dst, unsigned int *dlen);
 116 };
 117
 118 #define cra_cipher      cra_u.cipher
 119 #define cra_digest      cra_u.digest
 120 #define cra_compress    cra_u.compress
 121
 122 struct crypto_alg {
 123         struct list_head cra_list;
 124         u32 cra_flags;
 125         unsigned int cra_blocksize;
 126         unsigned int cra_ctxsize;
 127         const char cra_name[CRYPTO_MAX_ALG_NAME];
 128
 129         union {
 130                 struct cipher_alg cipher;
 131                 struct digest_alg digest;
 132                 struct compress_alg compress;
 133         } cra_u;
 134
 135         struct module *cra_module;
 136 };
 137
 138 /*
 139  * Algorithm registration interface.
 140  */
 141 int crypto_register_alg(struct crypto_alg *alg);
 142 int crypto_unregister_alg(struct crypto_alg *alg);
 143
 144 /*
 145  * Algorithm query interface.
 146  */
 147 #ifdef CONFIG_CRYPTO
 148 int crypto_alg_available(const char *name, u32 flags);
 149 #else
 150 static inline int crypto_alg_available(const char *name, u32 flags)
 151 {
 152         return 0;
 153 }
 154 #endif
 155
 156 /*
 157  * Transforms: user-instantiated objects which encapsulate algorithms
 158  * and core processing logic.  Managed via crypto_alloc_tfm() and
 159  * crypto_free_tfm(), as well as the various helpers below.
 160  */
 161
 162 struct cipher_tfm {
 163         void *cit_iv;
 164         unsigned int cit_ivsize;
 165         u32 cit_mode;
 166         int (*cit_setkey)(struct crypto_tfm *tfm,
 167                           const u8 *key, unsigned int keylen);
 168         int (*cit_encrypt)(struct crypto_tfm *tfm,
 169                            struct scatterlist *dst,
 170                            struct scatterlist *src,
 171                            unsigned int nbytes);
 172         int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
 173                               struct scatterlist *dst,
 174                               struct scatterlist *src,
 175                               unsigned int nbytes, u8 *iv);
 176         int (*cit_decrypt)(struct crypto_tfm *tfm,
 177                            struct scatterlist *dst,
 178                            struct scatterlist *src,
 179                            unsigned int nbytes);
 180         int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
 181                            struct scatterlist *dst,
 182                            struct scatterlist *src,
 183                            unsigned int nbytes, u8 *iv);
 184         void (*cit_xor_block)(u8 *dst, const u8 *src);
 185 };
 186
 187 struct digest_tfm {
 188         void (*dit_init)(struct crypto_tfm *tfm);
 189         void (*dit_update)(struct crypto_tfm *tfm,
 190                            struct scatterlist *sg, unsigned int nsg);
 191         void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
 192         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 193                            unsigned int nsg, u8 *out);
 194         int (*dit_setkey)(struct crypto_tfm *tfm,
 195                           const u8 *key, unsigned int keylen);
 196 #ifdef CONFIG_CRYPTO_HMAC
 197         void *dit_hmac_block;
 198 #endif
 199 };
 200
 201 struct compress_tfm {
 202         int (*cot_compress)(struct crypto_tfm *tfm,
 203                             const u8 *src, unsigned int slen,
 204                             u8 *dst, unsigned int *dlen);
 205         int (*cot_decompress)(struct crypto_tfm *tfm,
 206                               const u8 *src, unsigned int slen,
 207                               u8 *dst, unsigned int *dlen);
 208 };
 209
 210 #define crt_cipher      crt_u.cipher
 211 #define crt_digest      crt_u.digest
 212 #define crt_compress    crt_u.compress
 213
 214 struct crypto_tfm {
 215
 216         u32 crt_flags;
 217
 218         union {
 219                 struct cipher_tfm cipher;
 220                 struct digest_tfm digest;
 221                 struct compress_tfm compress;
 222         } crt_u;
 223
 224         struct crypto_alg *__crt_alg;
 225 };
 226
 227 /*
 228  * Transform user interface.
 229  */
 230
 231 /*
 232  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 233  * If that fails and the kernel supports dynamically loadable modules, it
 234  * will then attempt to load a module of the same name or alias.  A refcount
 235  * is grabbed on the algorithm which is then associated with the new transform.
 236  *
 237  * crypto_free_tfm() frees up the transform and any associated resources,
 238  * then drops the refcount on the associated algorithm.
 239  */
 240 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 241 void crypto_free_tfm(struct crypto_tfm *tfm);
 242
 243 /*
 244  * Transform helpers which query the underlying algorithm.
 245  */
 246 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 247 {
 248         return tfm->__crt_alg->cra_name;
 249 }
 250
 251 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 252 {
 253         return module_name(tfm->__crt_alg->cra_module);
 254 }
 255
 256 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 257 {
 258         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 259 }
 260
 261 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 262 {
 263         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 264         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 265 }
 266
 267 static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
 268 {
 269         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 270         return tfm->__crt_alg->cra_cipher.cia_max_keysize;
 271 }
 272
 273 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 274 {
 275         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 276         return tfm->crt_cipher.cit_ivsize;
 277 }
 278
 279 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 280 {
 281         return tfm->__crt_alg->cra_blocksize;
 282 }
 283
 284 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 285 {
 286         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 287         return tfm->__crt_alg->cra_digest.dia_digestsize;
 288 }
 289
 290 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
 291 {
 292         return (void *)&tfm[1];
 293 }
 294
 295 /*
 296  * API wrappers.
 297  */
 298 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 299 {
 300         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 301         tfm->crt_digest.dit_init(tfm);
 302 }
 303
 304 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 305                                         struct scatterlist *sg,
 306                                         unsigned int nsg)
 307 {
 308         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 309         tfm->crt_digest.dit_update(tfm, sg, nsg);
 310 }
 311
 312 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 313 {
 314         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 315         tfm->crt_digest.dit_final(tfm, out);
 316 }
 317
 318 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 319                                         struct scatterlist *sg,
 320                                         unsigned int nsg, u8 *out)
 321 {
 322         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 323         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 324 }
 325
 326 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 327                                        const u8 *key, unsigned int keylen)
 328 {
 329         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 330         if (tfm->crt_digest.dit_setkey == NULL)
 331                 return -ENOSYS;
 332         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 333 }
 334
 335 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 336                                        const u8 *key, unsigned int keylen)
 337 {
 338         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 339         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 340 }
 341
 342 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 343                                         struct scatterlist *dst,
 344                                         struct scatterlist *src,
 345                                         unsigned int nbytes)
 346 {
 347         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 348         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 349 }
 350
 351 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 352                                            struct scatterlist *dst,
 353                                            struct scatterlist *src,
 354                                            unsigned int nbytes, u8 *iv)
 355 {
 356         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 357         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 358         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 359 }
 360
 361 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 362                                         struct scatterlist *dst,
 363                                         struct scatterlist *src,
 364                                         unsigned int nbytes)
 365 {
 366         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 367         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 368 }
 369
 370 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 371                                            struct scatterlist *dst,
 372                                            struct scatterlist *src,
 373                                            unsigned int nbytes, u8 *iv)
 374 {
 375         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 376         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 377         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 378 }
 379
 380 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 381                                         const u8 *src, unsigned int len)
 382 {
 383         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 384         memcpy(tfm->crt_cipher.cit_iv, src, len);
 385 }
 386
 387 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 388                                         u8 *dst, unsigned int len)
 389 {
 390         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 391         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 392 }
 393
 394 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 395                                        const u8 *src, unsigned int slen,
 396                                        u8 *dst, unsigned int *dlen)
 397 {
 398         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 399         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 400 }
 401
 402 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 403                                          const u8 *src, unsigned int slen,
 404                                          u8 *dst, unsigned int *dlen)
 405 {
 406         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 407         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 408 }
 409
 410 /*
 411  * HMAC support.
 412  */
 413 #ifdef CONFIG_CRYPTO_HMAC
 414 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 415 void crypto_hmac_update(struct crypto_tfm *tfm,
 416                         struct scatterlist *sg, unsigned int nsg);
 417 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 418                        unsigned int *keylen, u8 *out);
 419 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 420                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 421 #endif  /* CONFIG_CRYPTO_HMAC */
 422
 423 #endif  /* _LINUX_CRYPTO_H */
 424