1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2  * All rights reserved.
3  *
4  * This package is an SSL implementation written
5  * by Eric Young (eay@cryptsoft.com).
6  * The implementation was written so as to conform with Netscapes SSL.
7  *
8  * This library is free for commercial and non-commercial use as long as
9  * the following conditions are aheared to.  The following conditions
10  * apply to all code found in this distribution, be it the RC4, RSA,
11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
12  * included with this distribution is covered by the same copyright terms
13  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
14  *
15  * Copyright remains Eric Young's, and as such any Copyright notices in
16  * the code are not to be removed.
17  * If this package is used in a product, Eric Young should be given attribution
18  * as the author of the parts of the library used.
19  * This can be in the form of a textual message at program startup or
20  * in documentation (online or textual) provided with the package.
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  * 1. Redistributions of source code must retain the copyright
26  *    notice, this list of conditions and the following disclaimer.
27  * 2. Redistributions in binary form must reproduce the above copyright
28  *    notice, this list of conditions and the following disclaimer in the
29  *    documentation and/or other materials provided with the distribution.
30  * 3. All advertising materials mentioning features or use of this software
31  *    must display the following acknowledgement:
32  *    "This product includes cryptographic software written by
33  *     Eric Young (eay@cryptsoft.com)"
34  *    The word 'cryptographic' can be left out if the rouines from the library
35  *    being used are not cryptographic related :-).
36  * 4. If you include any Windows specific code (or a derivative thereof) from
37  *    the apps directory (application code) you must include an acknowledgement:
38  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50  * SUCH DAMAGE.
51  *
52  * The licence and distribution terms for any publically available version or
53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
54  * copied and put under another distribution licence
55  * [including the GNU Public Licence.] */
56 
57 #ifndef OPENSSL_HEADER_CIPHER_H
58 #define OPENSSL_HEADER_CIPHER_H
59 
60 #include <openssl/base.h>
61 
62 #if defined(__cplusplus)
63 extern "C" {
64 #endif
65 
66 
67 /* Ciphers. */
68 
69 
70 /* Cipher primitives.
71  *
72  * The following functions return |EVP_CIPHER| objects that implement the named
73  * cipher algorithm. */
74 
75 OPENSSL_EXPORT const EVP_CIPHER *EVP_rc4(void);
76 
77 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_cbc(void);
78 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ecb(void);
79 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ede(void);
80 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ede_cbc(void);
81 OPENSSL_EXPORT const EVP_CIPHER *EVP_des_ede3_cbc(void);
82 
83 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_ecb(void);
84 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_cbc(void);
85 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_ctr(void);
86 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_ofb(void);
87 
88 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_ecb(void);
89 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_cbc(void);
90 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_ctr(void);
91 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_ofb(void);
92 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_xts(void);
93 
94 /* EVP_enc_null returns a 'cipher' that passes plaintext through as
95  * ciphertext. */
96 OPENSSL_EXPORT const EVP_CIPHER *EVP_enc_null(void);
97 
98 /* EVP_rc2_cbc returns a cipher that implements 128-bit RC2 in CBC mode. */
99 OPENSSL_EXPORT const EVP_CIPHER *EVP_rc2_cbc(void);
100 
101 /* EVP_rc2_40_cbc returns a cipher that implements 40-bit RC2 in CBC mode. This
102  * is obviously very, very weak and is included only in order to read PKCS#12
103  * files, which often encrypt the certificate chain using this cipher. It is
104  * deliberately not exported. */
105 const EVP_CIPHER *EVP_rc2_40_cbc(void);
106 
107 /* EVP_get_cipherbynid returns the cipher corresponding to the given NID, or
108  * NULL if no such cipher is known. */
109 OPENSSL_EXPORT const EVP_CIPHER *EVP_get_cipherbynid(int nid);
110 
111 
112 /* Cipher context allocation.
113  *
114  * An |EVP_CIPHER_CTX| represents the state of an encryption or decryption in
115  * progress. */
116 
117 /* EVP_CIPHER_CTX_init initialises an, already allocated, |EVP_CIPHER_CTX|. */
118 OPENSSL_EXPORT void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx);
119 
120 /* EVP_CIPHER_CTX_new allocates a fresh |EVP_CIPHER_CTX|, calls
121  * |EVP_CIPHER_CTX_init| and returns it, or NULL on allocation failure. */
122 OPENSSL_EXPORT EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void);
123 
124 /* EVP_CIPHER_CTX_cleanup frees any memory referenced by |ctx|. It returns
125  * one. */
126 OPENSSL_EXPORT int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *ctx);
127 
128 /* EVP_CIPHER_CTX_free calls |EVP_CIPHER_CTX_cleanup| on |ctx| and then frees
129  * |ctx| itself. */
130 OPENSSL_EXPORT void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx);
131 
132 /* EVP_CIPHER_CTX_copy sets |out| to be a duplicate of the current state of
133  * |in|. The |out| argument must have been previously initialised. */
134 OPENSSL_EXPORT int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out,
135                                        const EVP_CIPHER_CTX *in);
136 
137 
138 /* Cipher context configuration. */
139 
140 /* EVP_CipherInit_ex configures |ctx| for a fresh encryption (or decryption, if
141  * |enc| is zero) operation using |cipher|. If |ctx| has been previously
142  * configured with a cipher then |cipher|, |key| and |iv| may be |NULL| and
143  * |enc| may be -1 to reuse the previous values. The operation will use |key|
144  * as the key and |iv| as the IV (if any). These should have the correct
145  * lengths given by |EVP_CIPHER_key_length| and |EVP_CIPHER_iv_length|. It
146  * returns one on success and zero on error. */
147 OPENSSL_EXPORT int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx,
148                                      const EVP_CIPHER *cipher, ENGINE *engine,
149                                      const uint8_t *key, const uint8_t *iv,
150                                      int enc);
151 
152 /* EVP_EncryptInit_ex calls |EVP_CipherInit_ex| with |enc| equal to one. */
153 OPENSSL_EXPORT int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,
154                                       const EVP_CIPHER *cipher, ENGINE *impl,
155                                       const uint8_t *key, const uint8_t *iv);
156 
157 /* EVP_DecryptInit_ex calls |EVP_CipherInit_ex| with |enc| equal to zero. */
158 OPENSSL_EXPORT int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx,
159                                       const EVP_CIPHER *cipher, ENGINE *impl,
160                                       const uint8_t *key, const uint8_t *iv);
161 
162 
163 /* Cipher operations. */
164 
165 /* EVP_EncryptUpdate encrypts |in_len| bytes from |in| to |out|. The number
166  * of output bytes may be up to |in_len| plus the block length minus one and
167  * |out| must have sufficient space. The number of bytes actually output is
168  * written to |*out_len|. It returns one on success and zero otherwise. */
169 OPENSSL_EXPORT int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out,
170                                      int *out_len, const uint8_t *in,
171                                      int in_len);
172 
173 /* EVP_EncryptFinal_ex writes at most a block of ciphertext to |out| and sets
174  * |*out_len| to the number of bytes written. If padding is enabled (the
175  * default) then standard padding is applied to create the final block. If
176  * padding is disabled (with |EVP_CIPHER_CTX_set_padding|) then any partial
177  * block remaining will cause an error. The function returns one on success and
178  * zero otherwise. */
179 OPENSSL_EXPORT int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, uint8_t *out,
180                                        int *out_len);
181 
182 /* EVP_DecryptUpdate decrypts |in_len| bytes from |in| to |out|. The number of
183  * output bytes may be up to |in_len| plus the block length minus one and |out|
184  * must have sufficient space. The number of bytes actually output is written
185  * to |*out_len|. It returns one on success and zero otherwise. */
186 OPENSSL_EXPORT int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out,
187                                      int *out_len, const uint8_t *in,
188                                      int in_len);
189 
190 /* EVP_DecryptFinal_ex writes at most a block of ciphertext to |out| and sets
191  * |*out_len| to the number of bytes written. If padding is enabled (the
192  * default) then padding is removed from the final block.
193  *
194  * WARNING: it is unsafe to call this function with unauthenticted
195  * ciphertext if padding is enabled. */
196 OPENSSL_EXPORT int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out,
197                                        int *out_len);
198 
199 /* EVP_Cipher performs a one-shot encryption/decryption operation. No partial
200  * blocks are maintained between calls. However, any internal cipher state is
201  * still updated. For CBC-mode ciphers, the IV is updated to the final
202  * ciphertext block. For stream ciphers, the stream is advanced past the bytes
203  * used. It returns one on success and zero otherwise, unless |EVP_CIPHER_flags|
204  * has |EVP_CIPH_FLAG_CUSTOM_CIPHER| set. Then it returns the number of bytes
205  * written or -1 on error.
206  *
207  * WARNING: this differs from the usual return value convention when using
208  * |EVP_CIPH_FLAG_CUSTOM_CIPHER|.
209  *
210  * TODO(davidben): The normal ciphers currently never fail, even if, e.g.,
211  * |in_len| is not a multiple of the block size for CBC-mode decryption. The
212  * input just gets rounded up while the output gets truncated. This should
213  * either be officially documented or fail. */
214 OPENSSL_EXPORT int EVP_Cipher(EVP_CIPHER_CTX *ctx, uint8_t *out,
215                               const uint8_t *in, size_t in_len);
216 
217 /* EVP_CipherUpdate calls either |EVP_EncryptUpdate| or |EVP_DecryptUpdate|
218  * depending on how |ctx| has been setup. */
219 OPENSSL_EXPORT int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, uint8_t *out,
220                                     int *out_len, const uint8_t *in,
221                                     int in_len);
222 
223 /* EVP_CipherFinal_ex calls either |EVP_EncryptFinal_ex| or
224  * |EVP_DecryptFinal_ex| depending on how |ctx| has been setup. */
225 OPENSSL_EXPORT int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, uint8_t *out,
226                                       int *out_len);
227 
228 
229 /* Cipher context accessors. */
230 
231 /* EVP_CIPHER_CTX_cipher returns the |EVP_CIPHER| underlying |ctx|, or NULL if
232  * none has been set. */
233 OPENSSL_EXPORT const EVP_CIPHER *EVP_CIPHER_CTX_cipher(
234     const EVP_CIPHER_CTX *ctx);
235 
236 /* EVP_CIPHER_CTX_nid returns a NID identifying the |EVP_CIPHER| underlying
237  * |ctx| (e.g. |NID_aes_128_gcm|). It will crash if no cipher has been
238  * configured. */
239 OPENSSL_EXPORT int EVP_CIPHER_CTX_nid(const EVP_CIPHER_CTX *ctx);
240 
241 /* EVP_CIPHER_CTX_block_size returns the block size, in bytes, of the cipher
242  * underlying |ctx|, or one if the cipher is a stream cipher. It will crash if
243  * no cipher has been configured. */
244 OPENSSL_EXPORT unsigned EVP_CIPHER_CTX_block_size(const EVP_CIPHER_CTX *ctx);
245 
246 /* EVP_CIPHER_CTX_key_length returns the key size, in bytes, of the cipher
247  * underlying |ctx| or zero if no cipher has been configured. */
248 OPENSSL_EXPORT unsigned EVP_CIPHER_CTX_key_length(const EVP_CIPHER_CTX *ctx);
249 
250 /* EVP_CIPHER_CTX_iv_length returns the IV size, in bytes, of the cipher
251  * underlying |ctx|. It will crash if no cipher has been configured. */
252 OPENSSL_EXPORT unsigned EVP_CIPHER_CTX_iv_length(const EVP_CIPHER_CTX *ctx);
253 
254 /* EVP_CIPHER_CTX_get_app_data returns the opaque, application data pointer for
255  * |ctx|, or NULL if none has been set. */
256 OPENSSL_EXPORT void *EVP_CIPHER_CTX_get_app_data(const EVP_CIPHER_CTX *ctx);
257 
258 /* EVP_CIPHER_CTX_set_app_data sets the opaque, application data pointer for
259  * |ctx| to |data|. */
260 OPENSSL_EXPORT void EVP_CIPHER_CTX_set_app_data(EVP_CIPHER_CTX *ctx,
261                                                 void *data);
262 
263 /* EVP_CIPHER_CTX_flags returns a value which is the OR of zero or more
264  * |EVP_CIPH_*| flags. It will crash if no cipher has been configured. */
265 OPENSSL_EXPORT uint32_t EVP_CIPHER_CTX_flags(const EVP_CIPHER_CTX *ctx);
266 
267 /* EVP_CIPHER_CTX_mode returns one of the |EVP_CIPH_*| cipher mode values
268  * enumerated below. It will crash if no cipher has been configured. */
269 OPENSSL_EXPORT uint32_t EVP_CIPHER_CTX_mode(const EVP_CIPHER_CTX *ctx);
270 
271 /* EVP_CIPHER_CTX_ctrl is an |ioctl| like function. The |command| argument
272  * should be one of the |EVP_CTRL_*| values. The |arg| and |ptr| arguments are
273  * specific to the command in question. */
274 OPENSSL_EXPORT int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int command,
275                                        int arg, void *ptr);
276 
277 /* EVP_CIPHER_CTX_set_padding sets whether padding is enabled for |ctx| and
278  * returns one. Pass a non-zero |pad| to enable padding (the default) or zero
279  * to disable. */
280 OPENSSL_EXPORT int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad);
281 
282 /* EVP_CIPHER_CTX_set_key_length sets the key length for |ctx|. This is only
283  * valid for ciphers that can take a variable length key. It returns one on
284  * success and zero on error. */
285 OPENSSL_EXPORT int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *ctx, unsigned key_len);
286 
287 
288 /* Cipher accessors. */
289 
290 /* EVP_CIPHER_nid returns a NID identifing |cipher|. (For example,
291  * |NID_aes_128_gcm|.) */
292 OPENSSL_EXPORT int EVP_CIPHER_nid(const EVP_CIPHER *cipher);
293 
294 /* EVP_CIPHER_block_size returns the block size, in bytes, for |cipher|, or one
295  * if |cipher| is a stream cipher. */
296 OPENSSL_EXPORT unsigned EVP_CIPHER_block_size(const EVP_CIPHER *cipher);
297 
298 /* EVP_CIPHER_key_length returns the key size, in bytes, for |cipher|. If
299  * |cipher| can take a variable key length then this function returns the
300  * default key length and |EVP_CIPHER_flags| will return a value with
301  * |EVP_CIPH_VARIABLE_LENGTH| set. */
302 OPENSSL_EXPORT unsigned EVP_CIPHER_key_length(const EVP_CIPHER *cipher);
303 
304 /* EVP_CIPHER_iv_length returns the IV size, in bytes, of |cipher|, or zero if
305  * |cipher| doesn't take an IV. */
306 OPENSSL_EXPORT unsigned EVP_CIPHER_iv_length(const EVP_CIPHER *cipher);
307 
308 /* EVP_CIPHER_flags returns a value which is the OR of zero or more
309  * |EVP_CIPH_*| flags. */
310 OPENSSL_EXPORT uint32_t EVP_CIPHER_flags(const EVP_CIPHER *cipher);
311 
312 /* EVP_CIPHER_mode returns one of the cipher mode values enumerated below. */
313 OPENSSL_EXPORT uint32_t EVP_CIPHER_mode(const EVP_CIPHER *cipher);
314 
315 
316 /* Key derivation. */
317 
318 /* EVP_BytesToKey generates a key and IV for the cipher |type| by iterating
319  * |md| |count| times using |data| and |salt|. On entry, the |key| and |iv|
320  * buffers must have enough space to hold a key and IV for |type|. It returns
321  * the length of the key on success or zero on error. */
322 OPENSSL_EXPORT int EVP_BytesToKey(const EVP_CIPHER *type, const EVP_MD *md,
323                                   const uint8_t *salt, const uint8_t *data,
324                                   size_t data_len, unsigned count, uint8_t *key,
325                                   uint8_t *iv);
326 
327 
328 /* Cipher modes (for |EVP_CIPHER_mode|). */
329 
330 #define EVP_CIPH_STREAM_CIPHER 0x0
331 #define EVP_CIPH_ECB_MODE 0x1
332 #define EVP_CIPH_CBC_MODE 0x2
333 #define EVP_CIPH_CFB_MODE 0x3
334 #define EVP_CIPH_OFB_MODE 0x4
335 #define EVP_CIPH_CTR_MODE 0x5
336 #define EVP_CIPH_GCM_MODE 0x6
337 #define EVP_CIPH_XTS_MODE 0x7
338 
339 
340 /* Cipher flags (for |EVP_CIPHER_flags|). */
341 
342 /* EVP_CIPH_VARIABLE_LENGTH indicates that the cipher takes a variable length
343  * key. */
344 #define EVP_CIPH_VARIABLE_LENGTH 0x40
345 
346 /* EVP_CIPH_ALWAYS_CALL_INIT indicates that the |init| function for the cipher
347  * should always be called when initialising a new operation, even if the key
348  * is NULL to indicate that the same key is being used. */
349 #define EVP_CIPH_ALWAYS_CALL_INIT 0x80
350 
351 /* EVP_CIPH_CUSTOM_IV indicates that the cipher manages the IV itself rather
352  * than keeping it in the |iv| member of |EVP_CIPHER_CTX|. */
353 #define EVP_CIPH_CUSTOM_IV 0x100
354 
355 /* EVP_CIPH_CTRL_INIT indicates that EVP_CTRL_INIT should be used when
356  * initialising an |EVP_CIPHER_CTX|. */
357 #define EVP_CIPH_CTRL_INIT 0x200
358 
359 /* EVP_CIPH_FLAG_CUSTOM_CIPHER indicates that the cipher manages blocking
360  * itself. This causes EVP_(En|De)crypt_ex to be simple wrapper functions. */
361 #define EVP_CIPH_FLAG_CUSTOM_CIPHER 0x400
362 
363 /* EVP_CIPH_FLAG_AEAD_CIPHER specifies that the cipher is an AEAD. This is an
364  * older version of the proper AEAD interface. See aead.h for the current
365  * one. */
366 #define EVP_CIPH_FLAG_AEAD_CIPHER 0x800
367 
368 /* EVP_CIPH_CUSTOM_COPY indicates that the |ctrl| callback should be called
369  * with |EVP_CTRL_COPY| at the end of normal |EVP_CIPHER_CTX_copy|
370  * processing. */
371 #define EVP_CIPH_CUSTOM_COPY 0x1000
372 
373 
374 /* Deprecated functions */
375 
376 /* EVP_CipherInit acts like EVP_CipherInit_ex except that |EVP_CIPHER_CTX_init|
377  * is called on |cipher| first, if |cipher| is not NULL. */
378 OPENSSL_EXPORT int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
379                                   const uint8_t *key, const uint8_t *iv,
380                                   int enc);
381 
382 /* EVP_EncryptInit calls |EVP_CipherInit| with |enc| equal to one. */
383 OPENSSL_EXPORT int EVP_EncryptInit(EVP_CIPHER_CTX *ctx,
384                                    const EVP_CIPHER *cipher, const uint8_t *key,
385                                    const uint8_t *iv);
386 
387 /* EVP_DecryptInit calls |EVP_CipherInit| with |enc| equal to zero. */
388 OPENSSL_EXPORT int EVP_DecryptInit(EVP_CIPHER_CTX *ctx,
389                                    const EVP_CIPHER *cipher, const uint8_t *key,
390                                    const uint8_t *iv);
391 
392 /* EVP_add_cipher_alias does nothing and returns one. */
393 OPENSSL_EXPORT int EVP_add_cipher_alias(const char *a, const char *b);
394 
395 /* EVP_get_cipherbyname returns an |EVP_CIPHER| given a human readable name in
396  * |name|, or NULL if the name is unknown. */
397 OPENSSL_EXPORT const EVP_CIPHER *EVP_get_cipherbyname(const char *name);
398 
399 /* These AEADs are deprecated AES-GCM implementations that set
400  * |EVP_CIPH_FLAG_CUSTOM_CIPHER|. Use |EVP_aead_aes_128_gcm| and
401  * |EVP_aead_aes_256_gcm| instead. */
402 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_128_gcm(void);
403 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_256_gcm(void);
404 
405 /* These are deprecated, 192-bit version of AES. */
406 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_ecb(void);
407 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_cbc(void);
408 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_ctr(void);
409 OPENSSL_EXPORT const EVP_CIPHER *EVP_aes_192_gcm(void);
410 
411 
412 /* Private functions. */
413 
414 /* EVP_CIPH_NO_PADDING disables padding in block ciphers. */
415 #define EVP_CIPH_NO_PADDING 0x800
416 
417 /* EVP_CIPHER_CTX_ctrl commands. */
418 #define EVP_CTRL_INIT 0x0
419 #define EVP_CTRL_SET_KEY_LENGTH 0x1
420 #define EVP_CTRL_GET_RC2_KEY_BITS 0x2
421 #define EVP_CTRL_SET_RC2_KEY_BITS 0x3
422 #define EVP_CTRL_GET_RC5_ROUNDS 0x4
423 #define EVP_CTRL_SET_RC5_ROUNDS 0x5
424 #define EVP_CTRL_RAND_KEY 0x6
425 #define EVP_CTRL_PBE_PRF_NID 0x7
426 #define EVP_CTRL_COPY 0x8
427 #define EVP_CTRL_GCM_SET_IVLEN 0x9
428 #define EVP_CTRL_GCM_GET_TAG 0x10
429 #define EVP_CTRL_GCM_SET_TAG 0x11
430 #define EVP_CTRL_GCM_SET_IV_FIXED 0x12
431 #define EVP_CTRL_GCM_IV_GEN 0x13
432 #define EVP_CTRL_AEAD_SET_MAC_KEY 0x17
433 /* Set the GCM invocation field, decrypt only */
434 #define EVP_CTRL_GCM_SET_IV_INV 0x18
435 
436 /* GCM TLS constants */
437 /* Length of fixed part of IV derived from PRF */
438 #define EVP_GCM_TLS_FIXED_IV_LEN 4
439 /* Length of explicit part of IV part of TLS records */
440 #define EVP_GCM_TLS_EXPLICIT_IV_LEN 8
441 /* Length of tag for TLS */
442 #define EVP_GCM_TLS_TAG_LEN 16
443 
444 #define EVP_MAX_KEY_LENGTH 64
445 #define EVP_MAX_IV_LENGTH 16
446 #define EVP_MAX_BLOCK_LENGTH 32
447 
448 struct evp_cipher_ctx_st {
449   /* cipher contains the underlying cipher for this context. */
450   const EVP_CIPHER *cipher;
451 
452   /* app_data is a pointer to opaque, user data. */
453   void *app_data;      /* application stuff */
454 
455   /* cipher_data points to the |cipher| specific state. */
456   void *cipher_data;
457 
458   /* key_len contains the length of the key, which may differ from
459    * |cipher->key_len| if the cipher can take a variable key length. */
460   unsigned key_len;
461 
462   /* encrypt is one if encrypting and zero if decrypting. */
463   int encrypt;
464 
465   /* flags contains the OR of zero or more |EVP_CIPH_*| flags, above. */
466   uint32_t flags;
467 
468   /* oiv contains the original IV value. */
469   uint8_t oiv[EVP_MAX_IV_LENGTH];
470 
471   /* iv contains the current IV value, which may have been updated. */
472   uint8_t iv[EVP_MAX_IV_LENGTH];
473 
474   /* buf contains a partial block which is used by, for example, CTR mode to
475    * store unused keystream bytes. */
476   uint8_t buf[EVP_MAX_BLOCK_LENGTH];
477 
478   /* buf_len contains the number of bytes of a partial block contained in
479    * |buf|. */
480   int buf_len;
481 
482   /* num contains the number of bytes of |iv| which are valid for modes that
483    * manage partial blocks themselves. */
484   int num;
485 
486   /* final_used is non-zero if the |final| buffer contains plaintext. */
487   int final_used;
488 
489   /* block_mask contains |cipher->block_size| minus one. (The block size
490    * assumed to be a power of two.) */
491   int block_mask;
492 
493   uint8_t final[EVP_MAX_BLOCK_LENGTH]; /* possible final block */
494 } /* EVP_CIPHER_CTX */;
495 
496 typedef struct evp_cipher_info_st {
497   const EVP_CIPHER *cipher;
498   unsigned char iv[EVP_MAX_IV_LENGTH];
499 } EVP_CIPHER_INFO;
500 
501 struct evp_cipher_st {
502   /* type contains a NID identifing the cipher. (e.g. NID_aes_128_gcm.) */
503   int nid;
504 
505   /* block_size contains the block size, in bytes, of the cipher, or 1 for a
506    * stream cipher. */
507   unsigned block_size;
508 
509   /* key_len contains the key size, in bytes, for the cipher. If the cipher
510    * takes a variable key size then this contains the default size. */
511   unsigned key_len;
512 
513   /* iv_len contains the IV size, in bytes, or zero if inapplicable. */
514   unsigned iv_len;
515 
516   /* ctx_size contains the size, in bytes, of the per-key context for this
517    * cipher. */
518   unsigned ctx_size;
519 
520   /* flags contains the OR of a number of flags. See |EVP_CIPH_*|. */
521   uint32_t flags;
522 
523   /* app_data is a pointer to opaque, user data. */
524   void *app_data;
525 
526   int (*init)(EVP_CIPHER_CTX *ctx, const uint8_t *key, const uint8_t *iv,
527               int enc);
528 
529   int (*cipher)(EVP_CIPHER_CTX *ctx, uint8_t *out, const uint8_t *in,
530                 size_t inl);
531 
532   /* cleanup, if non-NULL, releases memory associated with the context. It is
533    * called if |EVP_CTRL_INIT| succeeds. Note that |init| may not have been
534    * called at this point. */
535   void (*cleanup)(EVP_CIPHER_CTX *);
536 
537   int (*ctrl)(EVP_CIPHER_CTX *, int type, int arg, void *ptr);
538 };
539 
540 
541 #if defined(__cplusplus)
542 }  /* extern C */
543 #endif
544 
545 #define CIPHER_R_AES_KEY_SETUP_FAILED 100
546 #define CIPHER_R_BAD_DECRYPT 101
547 #define CIPHER_R_BAD_KEY_LENGTH 102
548 #define CIPHER_R_BUFFER_TOO_SMALL 103
549 #define CIPHER_R_CTRL_NOT_IMPLEMENTED 104
550 #define CIPHER_R_CTRL_OPERATION_NOT_IMPLEMENTED 105
551 #define CIPHER_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH 106
552 #define CIPHER_R_INITIALIZATION_ERROR 107
553 #define CIPHER_R_INPUT_NOT_INITIALIZED 108
554 #define CIPHER_R_INVALID_AD_SIZE 109
555 #define CIPHER_R_INVALID_KEY_LENGTH 110
556 #define CIPHER_R_INVALID_NONCE_SIZE 111
557 #define CIPHER_R_INVALID_OPERATION 112
558 #define CIPHER_R_IV_TOO_LARGE 113
559 #define CIPHER_R_NO_CIPHER_SET 114
560 #define CIPHER_R_OUTPUT_ALIASES_INPUT 115
561 #define CIPHER_R_TAG_TOO_LARGE 116
562 #define CIPHER_R_TOO_LARGE 117
563 #define CIPHER_R_UNSUPPORTED_AD_SIZE 118
564 #define CIPHER_R_UNSUPPORTED_INPUT_SIZE 119
565 #define CIPHER_R_UNSUPPORTED_KEY_SIZE 120
566 #define CIPHER_R_UNSUPPORTED_NONCE_SIZE 121
567 #define CIPHER_R_UNSUPPORTED_TAG_SIZE 122
568 #define CIPHER_R_WRONG_FINAL_BLOCK_LENGTH 123
569 #define CIPHER_R_NO_DIRECTION_SET 124
570 
571 #endif  /* OPENSSL_HEADER_CIPHER_H */
572