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_final)(struct crypto_tfm *tfm, u8 *out);
 200         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
 201                            unsigned int nsg, u8 *out);
 202         int (*dit_setkey)(struct crypto_tfm *tfm,
 203                           const u8 *key, unsigned int keylen);
 204 #ifdef CONFIG_CRYPTO_HMAC
 205         void *dit_hmac_block;
 206 #endif
 207 };
 208
 209 struct compress_tfm {
 210         int (*cot_compress)(struct crypto_tfm *tfm,
 211                             const u8 *src, unsigned int slen,
 212                             u8 *dst, unsigned int *dlen);
 213         int (*cot_decompress)(struct crypto_tfm *tfm,
 214                               const u8 *src, unsigned int slen,
 215                               u8 *dst, unsigned int *dlen);
 216 };
 217
 218 #define crt_cipher      crt_u.cipher
 219 #define crt_digest      crt_u.digest
 220 #define crt_compress    crt_u.compress
 221
 222 struct crypto_tfm {
 223
 224         u32 crt_flags;
 225
 226         union {
 227                 struct cipher_tfm cipher;
 228                 struct digest_tfm digest;
 229                 struct compress_tfm compress;
 230         } crt_u;
 231
 232         struct crypto_alg *__crt_alg;
 233
 234         char __crt_ctx[] __attribute__ ((__aligned__));
 235 };
 236
 237 /*
 238  * Transform user interface.
 239  */
 240
 241 /*
 242  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
 243  * If that fails and the kernel supports dynamically loadable modules, it
 244  * will then attempt to load a module of the same name or alias.  A refcount
 245  * is grabbed on the algorithm which is then associated with the new transform.
 246  *
 247  * crypto_free_tfm() frees up the transform and any associated resources,
 248  * then drops the refcount on the associated algorithm.
 249  */
 250 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
 251 void crypto_free_tfm(struct crypto_tfm *tfm);
 252
 253 /*
 254  * Transform helpers which query the underlying algorithm.
 255  */
 256 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
 257 {
 258         return tfm->__crt_alg->cra_name;
 259 }
 260
 261 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
 262 {
 263         return module_name(tfm->__crt_alg->cra_module);
 264 }
 265
 266 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 267 {
 268         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 269 }
 270
 271 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 272 {
 273         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 274         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 275 }
 276
 277 static inline unsigned int crypto_tfm_alg_max_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_max_keysize;
 281 }
 282
 283 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 284 {
 285         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 286         return tfm->crt_cipher.cit_ivsize;
 287 }
 288
 289 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 290 {
 291         return tfm->__crt_alg->cra_blocksize;
 292 }
 293
 294 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 295 {
 296         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 297         return tfm->__crt_alg->cra_digest.dia_digestsize;
 298 }
 299
 300 static inline unsigned int crypto_tfm_alg_alignmask(struct crypto_tfm *tfm)
 301 {
 302         return tfm->__crt_alg->cra_alignmask;
 303 }
 304
 305 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
 306 {
 307         return tfm->__crt_ctx;
 308 }
 309
 310 static inline unsigned int crypto_tfm_ctx_alignment(void)
 311 {
 312         struct crypto_tfm *tfm;
 313         return __alignof__(tfm->__crt_ctx);
 314 }
 315
 316 /*
 317  * API wrappers.
 318  */
 319 static inline void crypto_digest_init(struct crypto_tfm *tfm)
 320 {
 321         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 322         tfm->crt_digest.dit_init(tfm);
 323 }
 324
 325 static inline void crypto_digest_update(struct crypto_tfm *tfm,
 326                                         struct scatterlist *sg,
 327                                         unsigned int nsg)
 328 {
 329         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 330         tfm->crt_digest.dit_update(tfm, sg, nsg);
 331 }
 332
 333 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
 334 {
 335         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 336         tfm->crt_digest.dit_final(tfm, out);
 337 }
 338
 339 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
 340                                         struct scatterlist *sg,
 341                                         unsigned int nsg, u8 *out)
 342 {
 343         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 344         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
 345 }
 346
 347 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
 348                                        const u8 *key, unsigned int keylen)
 349 {
 350         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 351         if (tfm->crt_digest.dit_setkey == NULL)
 352                 return -ENOSYS;
 353         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
 354 }
 355
 356 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
 357                                        const u8 *key, unsigned int keylen)
 358 {
 359         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 360         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
 361 }
 362
 363 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 364                                         struct scatterlist *dst,
 365                                         struct scatterlist *src,
 366                                         unsigned int nbytes)
 367 {
 368         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 369         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 370 }
 371
 372 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
 373                                            struct scatterlist *dst,
 374                                            struct scatterlist *src,
 375                                            unsigned int nbytes, u8 *iv)
 376 {
 377         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 378         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 379         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
 380 }
 381
 382 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 383                                         struct scatterlist *dst,
 384                                         struct scatterlist *src,
 385                                         unsigned int nbytes)
 386 {
 387         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 388         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 389 }
 390
 391 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
 392                                            struct scatterlist *dst,
 393                                            struct scatterlist *src,
 394                                            unsigned int nbytes, u8 *iv)
 395 {
 396         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 397         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
 398         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
 399 }
 400
 401 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
 402                                         const u8 *src, unsigned int len)
 403 {
 404         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 405         memcpy(tfm->crt_cipher.cit_iv, src, len);
 406 }
 407
 408 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 409                                         u8 *dst, unsigned int len)
 410 {
 411         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 412         memcpy(dst, tfm->crt_cipher.cit_iv, len);
 413 }
 414
 415 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
 416                                        const u8 *src, unsigned int slen,
 417                                        u8 *dst, unsigned int *dlen)
 418 {
 419         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 420         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
 421 }
 422
 423 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
 424                                          const u8 *src, unsigned int slen,
 425                                          u8 *dst, unsigned int *dlen)
 426 {
 427         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 428         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
 429 }
 430
 431 /*
 432  * HMAC support.
 433  */
 434 #ifdef CONFIG_CRYPTO_HMAC
 435 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
 436 void crypto_hmac_update(struct crypto_tfm *tfm,
 437                         struct scatterlist *sg, unsigned int nsg);
 438 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
 439                        unsigned int *keylen, u8 *out);
 440 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
 441                  struct scatterlist *sg, unsigned int nsg, u8 *out);
 442 #endif  /* CONFIG_CRYPTO_HMAC */
 443
 444 #endif  /* _LINUX_CRYPTO_H */
 445