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_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         const char cra_name[CRYPTO_MAX_ALG_NAME];
 130
 131         union {
 132                 struct cipher_alg cipher;
 133                 struct digest_alg digest;
 134                 struct compress_alg compress;
 135         } cra_u;
 136
 137         struct module *cra_module;
 138 };
 139
 140 /*
 141  * Algorithm registration interface.
 142  */
 143 int crypto_register_alg(struct crypto_alg *alg);
 144 int crypto_unregister_alg(struct crypto_alg *alg);
 145
 146 /*
 147  * Algorithm query interface.
 148  */
 149 #ifdef CONFIG_CRYPTO
 150 int crypto_alg_available(const char *name, u32 flags);
 151 #else
 152 static inline int crypto_alg_available(const char *name, u32 flags)
 153 {
 154         return 0;
 155 }
 156 #endif
 157
 158 /*
 159  * Transforms: user-instantiated objects which encapsulate algorithms
 160  * and core processing logic.  Managed via crypto_alloc_tfm() and
 161  * crypto_free_tfm(), as well as the various helpers below.
 162  */
 163
 164 struct cipher_tfm {
 165         void *cit_iv;
 166         unsigned int cit_ivsize;
 167         u32 cit_mode;
 168         int (*cit_setkey)(struct crypto_tfm *tfm,
 169                           const u8 *key, unsigned int keylen);
 170         int (*cit_encrypt)(struct crypto_tfm *tfm,
 171                            struct scatterlist *dst,
 172                            struct scatterlist *src,
 173                            unsigned int nbytes);
 174         int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
 175                               struct scatterlist *dst,
 176                               struct scatterlist *src,
 177                               unsigned int nbytes, u8 *iv);
 178         int (*cit_decrypt)(struct crypto_tfm *tfm,
 179                            struct scatterlist *dst,
 180                            struct scatterlist *src,
 181                            unsigned int nbytes);
 182         int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
 183                            struct scatterlist *dst,
 184                            struct scatterlist *src,
 185                            unsigned int nbytes, u8 *iv);
 186         void (*cit_xor_block)(u8 *dst, const u8 *src);
 187 };
 188
 189 struct digest_tfm {
 190         void (*dit_init)(struct crypto_tfm *tfm);
 191         void (*dit_update)(struct crypto_tfm *tfm,
 192                            struct scatterlist *sg, unsigned int nsg);
 193         void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
 194         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 195                            unsigned int nsg, u8 *out);
 196         int (*dit_setkey)(struct crypto_tfm *tfm,
 197                           const u8 *key, unsigned int keylen);
 198 #ifdef CONFIG_CRYPTO_HMAC
 199         void *dit_hmac_block;
 200 #endif
 201 };
 202
 203 struct compress_tfm {
 204         int (*cot_compress)(struct crypto_tfm *tfm,
 205                             const u8 *src, unsigned int slen,
 206                             u8 *dst, unsigned int *dlen);
 207         int (*cot_decompress)(struct crypto_tfm *tfm,
 208                               const u8 *src, unsigned int slen,
 209                               u8 *dst, unsigned int *dlen);
 210 };
 211
 212 #define crt_cipher      crt_u.cipher
 213 #define crt_digest      crt_u.digest
 214 #define crt_compress    crt_u.compress
 215
 216 struct crypto_tfm {
 217
 218         u32 crt_flags;
 219
 220         union {
 221                 struct cipher_tfm cipher;
 222                 struct digest_tfm digest;
 223                 struct compress_tfm compress;
 224         } crt_u;
 225
 226         struct crypto_alg *__crt_alg;
 227 };
 228
 229 /*
 230  * Transform user interface.
 231  */
 232
 233 /*
 234  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 235  * If that fails and the kernel supports dynamically loadable modules, it
 236  * will then attempt to load a module of the same name or alias.  A refcount
 237  * is grabbed on the algorithm which is then associated with the new transform.
 238  *
 239  * crypto_free_tfm() frees up the transform and any associated resources,
 240  * then drops the refcount on the associated algorithm.
 241  */
 242 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 243 void crypto_free_tfm(struct crypto_tfm *tfm);
 244
 245 /*
 246  * Transform helpers which query the underlying algorithm.
 247  */
 248 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 249 {
 250         return tfm->__crt_alg->cra_name;
 251 }
 252
 253 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 254 {
 255         return module_name(tfm->__crt_alg->cra_module);
 256 }
 257
 258 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 259 {
 260         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 261 }
 262
 263 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 264 {
 265         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 266         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 267 }
 268
 269 static inline unsigned int crypto_tfm_alg_max_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_max_keysize;
 273 }
 274
 275 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 276 {
 277         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 278         return tfm->crt_cipher.cit_ivsize;
 279 }
 280
 281 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 282 {
 283         return tfm->__crt_alg->cra_blocksize;
 284 }
 285
 286 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 287 {
 288         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 289         return tfm->__crt_alg->cra_digest.dia_digestsize;
 290 }
 291
 292 static inline unsigned int crypto_tfm_alg_alignmask(struct crypto_tfm *tfm)
 293 {
 294         return tfm->__crt_alg->cra_alignmask;
 295 }
 296
 297 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
 298 {
 299         return (void *)&tfm[1];
 300 }
 301
 302 /*
 303  * API wrappers.
 304  */
 305 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 306 {
 307         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 308         tfm->crt_digest.dit_init(tfm);
 309 }
 310
 311 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 312                                         struct scatterlist *sg,
 313                                         unsigned int nsg)
 314 {
 315         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 316         tfm->crt_digest.dit_update(tfm, sg, nsg);
 317 }
 318
 319 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 320 {
 321         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 322         tfm->crt_digest.dit_final(tfm, out);
 323 }
 324
 325 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 326                                         struct scatterlist *sg,
 327                                         unsigned int nsg, u8 *out)
 328 {
 329         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 330         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 331 }
 332
 333 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 334                                        const u8 *key, unsigned int keylen)
 335 {
 336         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 337         if (tfm->crt_digest.dit_setkey == NULL)
 338                 return -ENOSYS;
 339         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 340 }
 341
 342 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 343                                        const u8 *key, unsigned int keylen)
 344 {
 345         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 346         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 347 }
 348
 349 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 350                                         struct scatterlist *dst,
 351                                         struct scatterlist *src,
 352                                         unsigned int nbytes)
 353 {
 354         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 355         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 356 }
 357
 358 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 359                                            struct scatterlist *dst,
 360                                            struct scatterlist *src,
 361                                            unsigned int nbytes, u8 *iv)
 362 {
 363         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 364         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 365         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 366 }
 367
 368 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 369                                         struct scatterlist *dst,
 370                                         struct scatterlist *src,
 371                                         unsigned int nbytes)
 372 {
 373         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 374         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 375 }
 376
 377 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 378                                            struct scatterlist *dst,
 379                                            struct scatterlist *src,
 380                                            unsigned int nbytes, u8 *iv)
 381 {
 382         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 383         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 384         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 385 }
 386
 387 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 388                                         const u8 *src, unsigned int len)
 389 {
 390         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 391         memcpy(tfm->crt_cipher.cit_iv, src, len);
 392 }
 393
 394 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 395                                         u8 *dst, unsigned int len)
 396 {
 397         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 398         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 399 }
 400
 401 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 402                                        const u8 *src, unsigned int slen,
 403                                        u8 *dst, unsigned int *dlen)
 404 {
 405         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 406         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 407 }
 408
 409 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 410                                          const u8 *src, unsigned int slen,
 411                                          u8 *dst, unsigned int *dlen)
 412 {
 413         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 414         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 415 }
 416
 417 /*
 418  * HMAC support.
 419  */
 420 #ifdef CONFIG_CRYPTO_HMAC
 421 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 422 void crypto_hmac_update(struct crypto_tfm *tfm,
 423                         struct scatterlist *sg, unsigned int nsg);
 424 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 425                        unsigned int *keylen, u8 *out);
 426 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 427                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 428 #endif  /* CONFIG_CRYPTO_HMAC */
 429
 430 #endif  /* _LINUX_CRYPTO_H */
 431