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)(struct crypto_tfm *tfm, 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)(struct crypto_tfm *tfm, const u8 *key,
  83                           unsigned int keylen, u32 *flags);
  84         void (*cia_encrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
  85         void (*cia_decrypt)(struct crypto_tfm *tfm, 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)(struct crypto_tfm *tfm);
 104         void (*dia_update)(struct crypto_tfm *tfm, const u8 *data,
 105                            unsigned int len);
 106         void (*dia_final)(struct crypto_tfm *tfm, u8 *out);
 107         int (*dia_setkey)(struct crypto_tfm *tfm, const u8 *key,
 108                           unsigned int keylen, u32 *flags);
 109 };
 110
 111 struct compress_alg {
 112         int (*coa_compress)(struct crypto_tfm *tfm, const u8 *src,
 113                             unsigned int slen, u8 *dst, unsigned int *dlen);
 114         int (*coa_decompress)(struct crypto_tfm *tfm, const u8 *src,
 115                               unsigned int slen, 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         unsigned int cra_alignmask;
 128
 129         int cra_priority;
 130
 131         char cra_name[CRYPTO_MAX_ALG_NAME];
 132         char cra_driver_name[CRYPTO_MAX_ALG_NAME];
 133
 134         union {
 135                 struct cipher_alg cipher;
 136                 struct digest_alg digest;
 137                 struct compress_alg compress;
 138         } cra_u;
 139
 140         int (*cra_init)(struct crypto_tfm *tfm);
 141         void (*cra_exit)(struct crypto_tfm *tfm);
 142
 143         struct module *cra_module;
 144 };
 145
 146 /*
 147  * Algorithm registration interface.
 148  */
 149 int crypto_register_alg(struct crypto_alg *alg);
 150 int crypto_unregister_alg(struct crypto_alg *alg);
 151
 152 /*
 153  * Algorithm query interface.
 154  */
 155 #ifdef CONFIG_CRYPTO
 156 int crypto_alg_available(const char *name, u32 flags);
 157 #else
 158 static inline int crypto_alg_available(const char *name, u32 flags)
 159 {
 160         return 0;
 161 }
 162 #endif
 163
 164 /*
 165  * Transforms: user-instantiated objects which encapsulate algorithms
 166  * and core processing logic.  Managed via crypto_alloc_tfm() and
 167  * crypto_free_tfm(), as well as the various helpers below.
 168  */
 169
 170 struct cipher_tfm {
 171         void *cit_iv;
 172         unsigned int cit_ivsize;
 173         u32 cit_mode;
 174         int (*cit_setkey)(struct crypto_tfm *tfm,
 175                           const u8 *key, unsigned int keylen);
 176         int (*cit_encrypt)(struct crypto_tfm *tfm,
 177                            struct scatterlist *dst,
 178                            struct scatterlist *src,
 179                            unsigned int nbytes);
 180         int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
 181                               struct scatterlist *dst,
 182                               struct scatterlist *src,
 183                               unsigned int nbytes, u8 *iv);
 184         int (*cit_decrypt)(struct crypto_tfm *tfm,
 185                            struct scatterlist *dst,
 186                            struct scatterlist *src,
 187                            unsigned int nbytes);
 188         int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
 189                            struct scatterlist *dst,
 190                            struct scatterlist *src,
 191                            unsigned int nbytes, u8 *iv);
 192         void (*cit_xor_block)(u8 *dst, const u8 *src);
 193 };
 194
 195 struct digest_tfm {
 196         void (*dit_init)(struct crypto_tfm *tfm);
 197         void (*dit_update)(struct crypto_tfm *tfm,
 198                            struct scatterlist *sg, unsigned int nsg);
 199         void (*dit_update_kernel)(struct crypto_tfm *tfm,
 200                                   const void *data, size_t count);
 201         void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
 202         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 203                            unsigned int nsg, u8 *out);
 204         int (*dit_setkey)(struct crypto_tfm *tfm,
 205                           const u8 *key, unsigned int keylen);
 206 #ifdef CONFIG_CRYPTO_HMAC
 207         void *dit_hmac_block;
 208 #endif
 209 };
 210
 211 struct compress_tfm {
 212         int (*cot_compress)(struct crypto_tfm *tfm,
 213                             const u8 *src, unsigned int slen,
 214                             u8 *dst, unsigned int *dlen);
 215         int (*cot_decompress)(struct crypto_tfm *tfm,
 216                               const u8 *src, unsigned int slen,
 217                               u8 *dst, unsigned int *dlen);
 218 };
 219
 220 #define crt_cipher      crt_u.cipher
 221 #define crt_digest      crt_u.digest
 222 #define crt_compress    crt_u.compress
 223
 224 struct crypto_tfm {
 225
 226         u32 crt_flags;
 227
 228         union {
 229                 struct cipher_tfm cipher;
 230                 struct digest_tfm digest;
 231                 struct compress_tfm compress;
 232         } crt_u;
 233
 234         struct crypto_alg *__crt_alg;
 235
 236         char __crt_ctx[] __attribute__ ((__aligned__));
 237 };
 238
 239 /*
 240  * Transform user interface.
 241  */
 242
 243 /*
 244  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 245  * If that fails and the kernel supports dynamically loadable modules, it
 246  * will then attempt to load a module of the same name or alias.  A refcount
 247  * is grabbed on the algorithm which is then associated with the new transform.
 248  *
 249  * crypto_alloc_tfm2() is similar, but allows module loading to be suppressed.
 250  *
 251  * crypto_free_tfm() frees up the transform and any associated resources,
 252  * then drops the refcount on the associated algorithm.
 253  */
 254 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 255 struct crypto_tfm *crypto_alloc_tfm2(const char *alg_name, u32 tfm_flags,
 256                                      int nomodload);
 257 void crypto_free_tfm(struct crypto_tfm *tfm);
 258
 259 /*
 260  * Transform helpers which query the underlying algorithm.
 261  */
 262 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 263 {
 264         return tfm->__crt_alg->cra_name;
 265 }
 266
 267 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 268 {
 269         return module_name(tfm->__crt_alg->cra_module);
 270 }
 271
 272 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 273 {
 274         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 275 }
 276
 277 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 278 {
 279         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 280         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 281 }
 282
 283 static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
 284 {
 285         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 286         return tfm->__crt_alg->cra_cipher.cia_max_keysize;
 287 }
 288
 289 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 290 {
 291         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 292         return tfm->crt_cipher.cit_ivsize;
 293 }
 294
 295 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 296 {
 297         return tfm->__crt_alg->cra_blocksize;
 298 }
 299
 300 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 301 {
 302         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 303         return tfm->__crt_alg->cra_digest.dia_digestsize;
 304 }
 305
 306 static inline unsigned int crypto_tfm_alg_alignmask(struct crypto_tfm *tfm)
 307 {
 308         return tfm->__crt_alg->cra_alignmask;
 309 }
 310
 311 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
 312 {
 313         return tfm->__crt_ctx;
 314 }
 315
 316 static inline unsigned int crypto_tfm_ctx_alignment(void)
 317 {
 318         struct crypto_tfm *tfm;
 319         return __alignof__(tfm->__crt_ctx);
 320 }
 321
 322 /*
 323  * API wrappers.
 324  */
 325 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 326 {
 327         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 328         tfm->crt_digest.dit_init(tfm);
 329 }
 330
 331 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 332                                         struct scatterlist *sg,
 333                                         unsigned int nsg)
 334 {
 335         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 336         tfm->crt_digest.dit_update(tfm, sg, nsg);
 337 }
 338
 339 static inline void crypto_digest_update_kernel(struct crypto_tfm *tfm,
 340                                                const void *data,
 341                                                size_t count)
 342 {
 343         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 344         tfm->crt_digest.dit_update_kernel(tfm, data, count);
 345 }
 346
 347 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 348 {
 349         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 350         tfm->crt_digest.dit_final(tfm, out);
 351 }
 352
 353 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 354                                         struct scatterlist *sg,
 355                                         unsigned int nsg, u8 *out)
 356 {
 357         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 358         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 359 }
 360
 361 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 362                                        const u8 *key, unsigned int keylen)
 363 {
 364         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 365         if (tfm->crt_digest.dit_setkey == NULL)
 366                 return -ENOSYS;
 367         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 368 }
 369
 370 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 371                                        const u8 *key, unsigned int keylen)
 372 {
 373         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 374         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 375 }
 376
 377 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 378                                         struct scatterlist *dst,
 379                                         struct scatterlist *src,
 380                                         unsigned int nbytes)
 381 {
 382         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 383         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 384 }
 385
 386 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 387                                            struct scatterlist *dst,
 388                                            struct scatterlist *src,
 389                                            unsigned int nbytes, u8 *iv)
 390 {
 391         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 392         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 393         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 394 }
 395
 396 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 397                                         struct scatterlist *dst,
 398                                         struct scatterlist *src,
 399                                         unsigned int nbytes)
 400 {
 401         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 402         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 403 }
 404
 405 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 406                                            struct scatterlist *dst,
 407                                            struct scatterlist *src,
 408                                            unsigned int nbytes, u8 *iv)
 409 {
 410         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 411         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 412         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 413 }
 414
 415 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 416                                         const u8 *src, unsigned int len)
 417 {
 418         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 419         memcpy(tfm->crt_cipher.cit_iv, src, len);
 420 }
 421
 422 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 423                                         u8 *dst, unsigned int len)
 424 {
 425         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 426         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 427 }
 428
 429 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 430                                        const u8 *src, unsigned int slen,
 431                                        u8 *dst, unsigned int *dlen)
 432 {
 433         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 434         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 435 }
 436
 437 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 438                                          const u8 *src, unsigned int slen,
 439                                          u8 *dst, unsigned int *dlen)
 440 {
 441         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 442         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 443 }
 444
 445 /*
 446  * HMAC support.
 447  */
 448 #ifdef CONFIG_CRYPTO_HMAC
 449 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 450 void crypto_hmac_update(struct crypto_tfm *tfm,
 451                         struct scatterlist *sg, unsigned int nsg);
 452 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 453                        unsigned int *keylen, u8 *out);
 454 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 455                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 456 #endif  /* CONFIG_CRYPTO_HMAC */
 457
 458 #endif  /* _LINUX_CRYPTO_H */
 459