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  * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
   7  *
   8  * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
   9  * and Nettle, by Niels Möller.
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU General Public License as published by the Free
  13  * Software Foundation; either version 2 of the License, or (at your option)
  14  * any later version.
  15  *
  16  */
  17 #ifndef _LINUX_CRYPTO_H
  18 #define _LINUX_CRYPTO_H
  19
  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_REQ_MAY_SLEEP        0x00000200
  49 #define CRYPTO_TFM_RES_WEAK_KEY         0x00100000
  50 #define CRYPTO_TFM_RES_BAD_KEY_LEN      0x00200000
  51 #define CRYPTO_TFM_RES_BAD_KEY_SCHED    0x00400000
  52 #define CRYPTO_TFM_RES_BAD_BLOCK_LEN    0x00800000
  53 #define CRYPTO_TFM_RES_BAD_FLAGS        0x01000000
  54
  55 /*
  56  * Miscellaneous stuff.
  57  */
  58 #define CRYPTO_UNSPEC                   0
  59 #define CRYPTO_MAX_ALG_NAME             64
  60
  61 #define CRYPTO_DIR_ENCRYPT              1
  62 #define CRYPTO_DIR_DECRYPT              0
  63
  64 struct scatterlist;
  65 struct crypto_tfm;
  66
  67 struct cipher_desc {
  68         struct crypto_tfm *tfm;
  69         void (*crfn)(void *ctx, u8 *dst, const u8 *src);
  70         unsigned int (*prfn)(const struct cipher_desc *desc, u8 *dst,
  71                              const u8 *src, unsigned int nbytes);
  72         void *info;
  73 };
  74
  75 /*
  76  * Algorithms: modular crypto algorithm implementations, managed
  77  * via crypto_register_alg() and crypto_unregister_alg().
  78  */
  79 struct cipher_alg {
  80         unsigned int cia_min_keysize;
  81         unsigned int cia_max_keysize;
  82         int (*cia_setkey)(void *ctx, const u8 *key,
  83                           unsigned int keylen, u32 *flags);
  84         void (*cia_encrypt)(void *ctx, u8 *dst, const u8 *src);
  85         void (*cia_decrypt)(void *ctx, u8 *dst, const u8 *src);
  86
  87         unsigned int (*cia_encrypt_ecb)(const struct cipher_desc *desc,
  88                                         u8 *dst, const u8 *src,
  89                                         unsigned int nbytes);
  90         unsigned int (*cia_decrypt_ecb)(const struct cipher_desc *desc,
  91                                         u8 *dst, const u8 *src,
  92                                         unsigned int nbytes);
  93         unsigned int (*cia_encrypt_cbc)(const struct cipher_desc *desc,
  94                                         u8 *dst, const u8 *src,
  95                                         unsigned int nbytes);
  96         unsigned int (*cia_decrypt_cbc)(const struct cipher_desc *desc,
  97                                         u8 *dst, const u8 *src,
  98                                         unsigned int nbytes);
  99 };
 100
 101 struct digest_alg {
 102         unsigned int dia_digestsize;
 103         void (*dia_init)(void *ctx);
 104         void (*dia_update)(void *ctx, const u8 *data, unsigned int len);
 105         void (*dia_final)(void *ctx, u8 *out);
 106         int (*dia_setkey)(void *ctx, const u8 *key,
 107                           unsigned int keylen, u32 *flags);
 108 };
 109
 110 struct compress_alg {
 111         int (*coa_init)(void *ctx);
 112         void (*coa_exit)(void *ctx);
 113         int (*coa_compress)(void *ctx, const u8 *src, unsigned int slen,
 114                             u8 *dst, unsigned int *dlen);
 115         int (*coa_decompress)(void *ctx, const u8 *src, unsigned int slen,
 116                               u8 *dst, unsigned int *dlen);
 117 };
 118
 119 #define cra_cipher      cra_u.cipher
 120 #define cra_digest      cra_u.digest
 121 #define cra_compress    cra_u.compress
 122
 123 struct crypto_alg {
 124         struct list_head cra_list;
 125         u32 cra_flags;
 126         unsigned int cra_blocksize;
 127         unsigned int cra_ctxsize;
 128         unsigned int cra_alignmask;
 129
 130         int cra_priority;
 131
 132         const char cra_name[CRYPTO_MAX_ALG_NAME];
 133         const char cra_driver_name[CRYPTO_MAX_ALG_NAME];
 134
 135         union {
 136                 struct cipher_alg cipher;
 137                 struct digest_alg digest;
 138                 struct compress_alg compress;
 139         } cra_u;
 140
 141         struct module *cra_module;
 142 };
 143
 144 /*
 145  * Algorithm registration interface.
 146  */
 147 int crypto_register_alg(struct crypto_alg *alg);
 148 int crypto_unregister_alg(struct crypto_alg *alg);
 149
 150 /*
 151  * Algorithm query interface.
 152  */
 153 #ifdef CONFIG_CRYPTO
 154 int crypto_alg_available(const char *name, u32 flags);
 155 #else
 156 static inline int crypto_alg_available(const char *name, u32 flags)
 157 {
 158         return 0;
 159 }
 160 #endif
 161
 162 /*
 163  * Transforms: user-instantiated objects which encapsulate algorithms
 164  * and core processing logic.  Managed via crypto_alloc_tfm() and
 165  * crypto_free_tfm(), as well as the various helpers below.
 166  */
 167
 168 struct cipher_tfm {
 169         void *cit_iv;
 170         unsigned int cit_ivsize;
 171         u32 cit_mode;
 172         int (*cit_setkey)(struct crypto_tfm *tfm,
 173                           const u8 *key, unsigned int keylen);
 174         int (*cit_encrypt)(struct crypto_tfm *tfm,
 175                            struct scatterlist *dst,
 176                            struct scatterlist *src,
 177                            unsigned int nbytes);
 178         int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
 179                               struct scatterlist *dst,
 180                               struct scatterlist *src,
 181                               unsigned int nbytes, u8 *iv);
 182         int (*cit_decrypt)(struct crypto_tfm *tfm,
 183                            struct scatterlist *dst,
 184                            struct scatterlist *src,
 185                            unsigned int nbytes);
 186         int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
 187                            struct scatterlist *dst,
 188                            struct scatterlist *src,
 189                            unsigned int nbytes, u8 *iv);
 190         void (*cit_xor_block)(u8 *dst, const u8 *src);
 191 };
 192
 193 struct digest_tfm {
 194         void (*dit_init)(struct crypto_tfm *tfm);
 195         void (*dit_update)(struct crypto_tfm *tfm,
 196                            struct scatterlist *sg, unsigned int nsg);
 197         void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
 198         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 199                            unsigned int nsg, u8 *out);
 200         int (*dit_setkey)(struct crypto_tfm *tfm,
 201                           const u8 *key, unsigned int keylen);
 202 #ifdef CONFIG_CRYPTO_HMAC
 203         void *dit_hmac_block;
 204 #endif
 205 };
 206
 207 struct compress_tfm {
 208         int (*cot_compress)(struct crypto_tfm *tfm,
 209                             const u8 *src, unsigned int slen,
 210                             u8 *dst, unsigned int *dlen);
 211         int (*cot_decompress)(struct crypto_tfm *tfm,
 212                               const u8 *src, unsigned int slen,
 213                               u8 *dst, unsigned int *dlen);
 214 };
 215
 216 #define crt_cipher      crt_u.cipher
 217 #define crt_digest      crt_u.digest
 218 #define crt_compress    crt_u.compress
 219
 220 struct crypto_tfm {
 221
 222         u32 crt_flags;
 223
 224         union {
 225                 struct cipher_tfm cipher;
 226                 struct digest_tfm digest;
 227                 struct compress_tfm compress;
 228         } crt_u;
 229
 230         struct crypto_alg *__crt_alg;
 231
 232         char __crt_ctx[] __attribute__ ((__aligned__));
 233 };
 234
 235 /*
 236  * Transform user interface.
 237  */
 238
 239 /*
 240  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 241  * If that fails and the kernel supports dynamically loadable modules, it
 242  * will then attempt to load a module of the same name or alias.  A refcount
 243  * is grabbed on the algorithm which is then associated with the new transform.
 244  *
 245  * crypto_free_tfm() frees up the transform and any associated resources,
 246  * then drops the refcount on the associated algorithm.
 247  */
 248 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 249 void crypto_free_tfm(struct crypto_tfm *tfm);
 250
 251 /*
 252  * Transform helpers which query the underlying algorithm.
 253  */
 254 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 255 {
 256         return tfm->__crt_alg->cra_name;
 257 }
 258
 259 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 260 {
 261         return module_name(tfm->__crt_alg->cra_module);
 262 }
 263
 264 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 265 {
 266         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 267 }
 268
 269 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 270 {
 271         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 272         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 273 }
 274
 275 static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
 276 {
 277         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 278         return tfm->__crt_alg->cra_cipher.cia_max_keysize;
 279 }
 280
 281 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 282 {
 283         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 284         return tfm->crt_cipher.cit_ivsize;
 285 }
 286
 287 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 288 {
 289         return tfm->__crt_alg->cra_blocksize;
 290 }
 291
 292 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 293 {
 294         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 295         return tfm->__crt_alg->cra_digest.dia_digestsize;
 296 }
 297
 298 static inline unsigned int crypto_tfm_alg_alignmask(struct crypto_tfm *tfm)
 299 {
 300         return tfm->__crt_alg->cra_alignmask;
 301 }
 302
 303 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
 304 {
 305         return tfm->__crt_ctx;
 306 }
 307
 308 static inline unsigned int crypto_tfm_ctx_alignment(void)
 309 {
 310         struct crypto_tfm *tfm;
 311         return __alignof__(tfm->__crt_ctx);
 312 }
 313
 314 /*
 315  * API wrappers.
 316  */
 317 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 318 {
 319         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 320         tfm->crt_digest.dit_init(tfm);
 321 }
 322
 323 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 324                                         struct scatterlist *sg,
 325                                         unsigned int nsg)
 326 {
 327         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 328         tfm->crt_digest.dit_update(tfm, sg, nsg);
 329 }
 330
 331 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 332 {
 333         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 334         tfm->crt_digest.dit_final(tfm, out);
 335 }
 336
 337 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 338                                         struct scatterlist *sg,
 339                                         unsigned int nsg, u8 *out)
 340 {
 341         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 342         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 343 }
 344
 345 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 346                                        const u8 *key, unsigned int keylen)
 347 {
 348         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 349         if (tfm->crt_digest.dit_setkey == NULL)
 350                 return -ENOSYS;
 351         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 352 }
 353
 354 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 355                                        const u8 *key, unsigned int keylen)
 356 {
 357         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 358         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 359 }
 360
 361 static inline int crypto_cipher_encrypt(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_encrypt(tfm, dst, src, nbytes);
 368 }
 369
 370 static inline int crypto_cipher_encrypt_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_encrypt_iv(tfm, dst, src, nbytes, iv);
 378 }
 379
 380 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 381                                         struct scatterlist *dst,
 382                                         struct scatterlist *src,
 383                                         unsigned int nbytes)
 384 {
 385         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 386         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 387 }
 388
 389 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 390                                            struct scatterlist *dst,
 391                                            struct scatterlist *src,
 392                                            unsigned int nbytes, u8 *iv)
 393 {
 394         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 395         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 396         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 397 }
 398
 399 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 400                                         const u8 *src, unsigned int len)
 401 {
 402         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 403         memcpy(tfm->crt_cipher.cit_iv, src, len);
 404 }
 405
 406 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 407                                         u8 *dst, unsigned int len)
 408 {
 409         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 410         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 411 }
 412
 413 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 414                                        const u8 *src, unsigned int slen,
 415                                        u8 *dst, unsigned int *dlen)
 416 {
 417         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 418         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 419 }
 420
 421 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 422                                          const u8 *src, unsigned int slen,
 423                                          u8 *dst, unsigned int *dlen)
 424 {
 425         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 426         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 427 }
 428
 429 /*
 430  * HMAC support.
 431  */
 432 #ifdef CONFIG_CRYPTO_HMAC
 433 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 434 void crypto_hmac_update(struct crypto_tfm *tfm,
 435                         struct scatterlist *sg, unsigned int nsg);
 436 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 437                        unsigned int *keylen, u8 *out);
 438 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 439                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 440 #endif  /* CONFIG_CRYPTO_HMAC */
 441
 442 #endif  /* _LINUX_CRYPTO_H */
 443