Linux-2.6.12-rc2
[linux-2.6.git] / 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
65 /*
66  * Algorithms: modular crypto algorithm implementations, managed
67  * via crypto_register_alg() and crypto_unregister_alg().
68  */
69 struct cipher_alg {
70         unsigned int cia_min_keysize;
71         unsigned int cia_max_keysize;
72         int (*cia_setkey)(void *ctx, const u8 *key,
73                           unsigned int keylen, u32 *flags);
74         void (*cia_encrypt)(void *ctx, u8 *dst, const u8 *src);
75         void (*cia_decrypt)(void *ctx, u8 *dst, const u8 *src);
76 };
77
78 struct digest_alg {
79         unsigned int dia_digestsize;
80         void (*dia_init)(void *ctx);
81         void (*dia_update)(void *ctx, const u8 *data, unsigned int len);
82         void (*dia_final)(void *ctx, u8 *out);
83         int (*dia_setkey)(void *ctx, const u8 *key,
84                           unsigned int keylen, u32 *flags);
85 };
86
87 struct compress_alg {
88         int (*coa_init)(void *ctx);
89         void (*coa_exit)(void *ctx);
90         int (*coa_compress)(void *ctx, const u8 *src, unsigned int slen,
91                             u8 *dst, unsigned int *dlen);
92         int (*coa_decompress)(void *ctx, const u8 *src, unsigned int slen,
93                               u8 *dst, unsigned int *dlen);
94 };
95
96 #define cra_cipher      cra_u.cipher
97 #define cra_digest      cra_u.digest
98 #define cra_compress    cra_u.compress
99
100 struct crypto_alg {
101         struct list_head cra_list;
102         u32 cra_flags;
103         unsigned int cra_blocksize;
104         unsigned int cra_ctxsize;
105         const char cra_name[CRYPTO_MAX_ALG_NAME];
106
107         union {
108                 struct cipher_alg cipher;
109                 struct digest_alg digest;
110                 struct compress_alg compress;
111         } cra_u;
112         
113         struct module *cra_module;
114 };
115
116 /*
117  * Algorithm registration interface.
118  */
119 int crypto_register_alg(struct crypto_alg *alg);
120 int crypto_unregister_alg(struct crypto_alg *alg);
121
122 /*
123  * Algorithm query interface.
124  */
125 #ifdef CONFIG_CRYPTO
126 int crypto_alg_available(const char *name, u32 flags);
127 #else
128 static inline int crypto_alg_available(const char *name, u32 flags)
129 {
130         return 0;
131 }
132 #endif
133
134 /*
135  * Transforms: user-instantiated objects which encapsulate algorithms
136  * and core processing logic.  Managed via crypto_alloc_tfm() and
137  * crypto_free_tfm(), as well as the various helpers below.
138  */
139 struct crypto_tfm;
140
141 struct cipher_tfm {
142         void *cit_iv;
143         unsigned int cit_ivsize;
144         u32 cit_mode;
145         int (*cit_setkey)(struct crypto_tfm *tfm,
146                           const u8 *key, unsigned int keylen);
147         int (*cit_encrypt)(struct crypto_tfm *tfm,
148                            struct scatterlist *dst,
149                            struct scatterlist *src,
150                            unsigned int nbytes);
151         int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
152                               struct scatterlist *dst,
153                               struct scatterlist *src,
154                               unsigned int nbytes, u8 *iv);
155         int (*cit_decrypt)(struct crypto_tfm *tfm,
156                            struct scatterlist *dst,
157                            struct scatterlist *src,
158                            unsigned int nbytes);
159         int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
160                            struct scatterlist *dst,
161                            struct scatterlist *src,
162                            unsigned int nbytes, u8 *iv);
163         void (*cit_xor_block)(u8 *dst, const u8 *src);
164 };
165
166 struct digest_tfm {
167         void (*dit_init)(struct crypto_tfm *tfm);
168         void (*dit_update)(struct crypto_tfm *tfm,
169                            struct scatterlist *sg, unsigned int nsg);
170         void (*dit_final)(struct crypto_tfm *tfm, u8 *out);
171         void (*dit_digest)(struct crypto_tfm *tfm, struct scatterlist *sg,
172                            unsigned int nsg, u8 *out);
173         int (*dit_setkey)(struct crypto_tfm *tfm,
174                           const u8 *key, unsigned int keylen);
175 #ifdef CONFIG_CRYPTO_HMAC
176         void *dit_hmac_block;
177 #endif
178 };
179
180 struct compress_tfm {
181         int (*cot_compress)(struct crypto_tfm *tfm,
182                             const u8 *src, unsigned int slen,
183                             u8 *dst, unsigned int *dlen);
184         int (*cot_decompress)(struct crypto_tfm *tfm,
185                               const u8 *src, unsigned int slen,
186                               u8 *dst, unsigned int *dlen);
187 };
188
189 #define crt_cipher      crt_u.cipher
190 #define crt_digest      crt_u.digest
191 #define crt_compress    crt_u.compress
192
193 struct crypto_tfm {
194
195         u32 crt_flags;
196         
197         union {
198                 struct cipher_tfm cipher;
199                 struct digest_tfm digest;
200                 struct compress_tfm compress;
201         } crt_u;
202         
203         struct crypto_alg *__crt_alg;
204 };
205
206 /* 
207  * Transform user interface.
208  */
209  
210 /*
211  * crypto_alloc_tfm() will first attempt to locate an already loaded algorithm.
212  * If that fails and the kernel supports dynamically loadable modules, it
213  * will then attempt to load a module of the same name or alias.  A refcount
214  * is grabbed on the algorithm which is then associated with the new transform.
215  *
216  * crypto_free_tfm() frees up the transform and any associated resources,
217  * then drops the refcount on the associated algorithm.
218  */
219 struct crypto_tfm *crypto_alloc_tfm(const char *alg_name, u32 tfm_flags);
220 void crypto_free_tfm(struct crypto_tfm *tfm);
221
222 /*
223  * Transform helpers which query the underlying algorithm.
224  */
225 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
226 {
227         return tfm->__crt_alg->cra_name;
228 }
229
230 static inline const char *crypto_tfm_alg_modname(struct crypto_tfm *tfm)
231 {
232         return module_name(tfm->__crt_alg->cra_module);
233 }
234
235 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
236 {
237         return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
238 }
239
240 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
241 {
242         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
243         return tfm->__crt_alg->cra_cipher.cia_min_keysize;
244 }
245
246 static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
247 {
248         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
249         return tfm->__crt_alg->cra_cipher.cia_max_keysize;
250 }
251
252 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
253 {
254         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
255         return tfm->crt_cipher.cit_ivsize;
256 }
257
258 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
259 {
260         return tfm->__crt_alg->cra_blocksize;
261 }
262
263 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
264 {
265         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
266         return tfm->__crt_alg->cra_digest.dia_digestsize;
267 }
268
269 /*
270  * API wrappers.
271  */
272 static inline void crypto_digest_init(struct crypto_tfm *tfm)
273 {
274         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
275         tfm->crt_digest.dit_init(tfm);
276 }
277
278 static inline void crypto_digest_update(struct crypto_tfm *tfm,
279                                         struct scatterlist *sg,
280                                         unsigned int nsg)
281 {
282         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
283         tfm->crt_digest.dit_update(tfm, sg, nsg);
284 }
285
286 static inline void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
287 {
288         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
289         tfm->crt_digest.dit_final(tfm, out);
290 }
291
292 static inline void crypto_digest_digest(struct crypto_tfm *tfm,
293                                         struct scatterlist *sg,
294                                         unsigned int nsg, u8 *out)
295 {
296         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
297         tfm->crt_digest.dit_digest(tfm, sg, nsg, out);
298 }
299
300 static inline int crypto_digest_setkey(struct crypto_tfm *tfm,
301                                        const u8 *key, unsigned int keylen)
302 {
303         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
304         if (tfm->crt_digest.dit_setkey == NULL)
305                 return -ENOSYS;
306         return tfm->crt_digest.dit_setkey(tfm, key, keylen);
307 }
308
309 static inline int crypto_cipher_setkey(struct crypto_tfm *tfm,
310                                        const u8 *key, unsigned int keylen)
311 {
312         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
313         return tfm->crt_cipher.cit_setkey(tfm, key, keylen);
314 }
315
316 static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
317                                         struct scatterlist *dst,
318                                         struct scatterlist *src,
319                                         unsigned int nbytes)
320 {
321         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
322         return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
323 }                                        
324
325 static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
326                                            struct scatterlist *dst,
327                                            struct scatterlist *src,
328                                            unsigned int nbytes, u8 *iv)
329 {
330         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
331         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
332         return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
333 }                                        
334
335 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
336                                         struct scatterlist *dst,
337                                         struct scatterlist *src,
338                                         unsigned int nbytes)
339 {
340         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
341         return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
342 }
343
344 static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
345                                            struct scatterlist *dst,
346                                            struct scatterlist *src,
347                                            unsigned int nbytes, u8 *iv)
348 {
349         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
350         BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
351         return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
352 }
353
354 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
355                                         const u8 *src, unsigned int len)
356 {
357         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
358         memcpy(tfm->crt_cipher.cit_iv, src, len);
359 }
360
361 static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
362                                         u8 *dst, unsigned int len)
363 {
364         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
365         memcpy(dst, tfm->crt_cipher.cit_iv, len);
366 }
367
368 static inline int crypto_comp_compress(struct crypto_tfm *tfm,
369                                        const u8 *src, unsigned int slen,
370                                        u8 *dst, unsigned int *dlen)
371 {
372         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
373         return tfm->crt_compress.cot_compress(tfm, src, slen, dst, dlen);
374 }
375
376 static inline int crypto_comp_decompress(struct crypto_tfm *tfm,
377                                          const u8 *src, unsigned int slen,
378                                          u8 *dst, unsigned int *dlen)
379 {
380         BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
381         return tfm->crt_compress.cot_decompress(tfm, src, slen, dst, dlen);
382 }
383
384 /*
385  * HMAC support.
386  */
387 #ifdef CONFIG_CRYPTO_HMAC
388 void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen);
389 void crypto_hmac_update(struct crypto_tfm *tfm,
390                         struct scatterlist *sg, unsigned int nsg);
391 void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
392                        unsigned int *keylen, u8 *out);
393 void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
394                  struct scatterlist *sg, unsigned int nsg, u8 *out);
395 #endif  /* CONFIG_CRYPTO_HMAC */
396
397 #endif  /* _LINUX_CRYPTO_H */
398