1 /**
2 * \file cipher.h
3 *
4 * \brief This file contains an abstraction interface for use with the cipher
5 * primitives provided by the library. It provides a common interface to all of
6 * the available cipher operations.
7 *
8 * \author Adriaan de Jong <dejong@fox-it.com>
9 */
10 /*
11 * Copyright The Mbed TLS Contributors
12 * SPDX-License-Identifier: Apache-2.0
13 *
14 * Licensed under the Apache License, Version 2.0 (the "License"); you may
15 * not use this file except in compliance with the License.
16 * You may obtain a copy of the License at
17 *
18 * http://www.apache.org/licenses/LICENSE-2.0
19 *
20 * Unless required by applicable law or agreed to in writing, software
21 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
22 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
23 * See the License for the specific language governing permissions and
24 * limitations under the License.
25 */
26
27 #ifndef MBEDTLS_CIPHER_H
28 #define MBEDTLS_CIPHER_H
29 #include "mbedtls/private_access.h"
30
31 #include "mbedtls/build_info.h"
32
33 #include <stddef.h>
34 #include "mbedtls/platform_util.h"
35
36 #if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CCM_C) || defined(MBEDTLS_CHACHAPOLY_C)
37 #define MBEDTLS_CIPHER_MODE_AEAD
38 #endif
39
40 #if defined(MBEDTLS_CIPHER_MODE_CBC)
41 #define MBEDTLS_CIPHER_MODE_WITH_PADDING
42 #endif
43
44 #if defined(MBEDTLS_CIPHER_NULL_CIPHER) || \
45 defined(MBEDTLS_CHACHA20_C)
46 #define MBEDTLS_CIPHER_MODE_STREAM
47 #endif
48
49 #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
50 !defined(inline) && !defined(__cplusplus)
51 #define inline __inline
52 #endif
53
54 /** The selected feature is not available. */
55 #define MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE -0x6080
56 /** Bad input parameters. */
57 #define MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA -0x6100
58 /** Failed to allocate memory. */
59 #define MBEDTLS_ERR_CIPHER_ALLOC_FAILED -0x6180
60 /** Input data contains invalid padding and is rejected. */
61 #define MBEDTLS_ERR_CIPHER_INVALID_PADDING -0x6200
62 /** Decryption of block requires a full block. */
63 #define MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED -0x6280
64 /** Authentication failed (for AEAD modes). */
65 #define MBEDTLS_ERR_CIPHER_AUTH_FAILED -0x6300
66 /** The context is invalid. For example, because it was freed. */
67 #define MBEDTLS_ERR_CIPHER_INVALID_CONTEXT -0x6380
68
69 #define MBEDTLS_CIPHER_VARIABLE_IV_LEN 0x01 /**< Cipher accepts IVs of variable length. */
70 #define MBEDTLS_CIPHER_VARIABLE_KEY_LEN 0x02 /**< Cipher accepts keys of variable length. */
71
72 #ifdef __cplusplus
73 extern "C" {
74 #endif
75
76 /**
77 * \brief Supported cipher types.
78 *
79 * \warning DES is considered weak cipher and its use
80 * constitutes a security risk. Arm recommends considering stronger
81 * ciphers instead.
82 */
83 typedef enum {
84 MBEDTLS_CIPHER_ID_NONE = 0, /**< Placeholder to mark the end of cipher ID lists. */
85 MBEDTLS_CIPHER_ID_NULL, /**< The identity cipher, treated as a stream cipher. */
86 MBEDTLS_CIPHER_ID_AES, /**< The AES cipher. */
87 MBEDTLS_CIPHER_ID_DES, /**< The DES cipher. */
88 MBEDTLS_CIPHER_ID_3DES, /**< The Triple DES cipher. */
89 MBEDTLS_CIPHER_ID_CAMELLIA, /**< The Camellia cipher. */
90 MBEDTLS_CIPHER_ID_ARIA, /**< The Aria cipher. */
91 MBEDTLS_CIPHER_ID_CHACHA20, /**< The ChaCha20 cipher. */
92 } mbedtls_cipher_id_t;
93
94 /**
95 * \brief Supported {cipher type, cipher mode} pairs.
96 *
97 * \warning DES is considered weak cipher and its use
98 * constitutes a security risk. Arm recommends considering stronger
99 * ciphers instead.
100 */
101 typedef enum {
102 MBEDTLS_CIPHER_NONE = 0, /**< Placeholder to mark the end of cipher-pair lists. */
103 MBEDTLS_CIPHER_NULL, /**< The identity stream cipher. */
104 MBEDTLS_CIPHER_AES_128_ECB, /**< AES cipher with 128-bit ECB mode. */
105 MBEDTLS_CIPHER_AES_192_ECB, /**< AES cipher with 192-bit ECB mode. */
106 MBEDTLS_CIPHER_AES_256_ECB, /**< AES cipher with 256-bit ECB mode. */
107 MBEDTLS_CIPHER_AES_128_CBC, /**< AES cipher with 128-bit CBC mode. */
108 MBEDTLS_CIPHER_AES_192_CBC, /**< AES cipher with 192-bit CBC mode. */
109 MBEDTLS_CIPHER_AES_256_CBC, /**< AES cipher with 256-bit CBC mode. */
110 MBEDTLS_CIPHER_AES_128_CFB128, /**< AES cipher with 128-bit CFB128 mode. */
111 MBEDTLS_CIPHER_AES_192_CFB128, /**< AES cipher with 192-bit CFB128 mode. */
112 MBEDTLS_CIPHER_AES_256_CFB128, /**< AES cipher with 256-bit CFB128 mode. */
113 MBEDTLS_CIPHER_AES_128_CTR, /**< AES cipher with 128-bit CTR mode. */
114 MBEDTLS_CIPHER_AES_192_CTR, /**< AES cipher with 192-bit CTR mode. */
115 MBEDTLS_CIPHER_AES_256_CTR, /**< AES cipher with 256-bit CTR mode. */
116 MBEDTLS_CIPHER_AES_128_GCM, /**< AES cipher with 128-bit GCM mode. */
117 MBEDTLS_CIPHER_AES_192_GCM, /**< AES cipher with 192-bit GCM mode. */
118 MBEDTLS_CIPHER_AES_256_GCM, /**< AES cipher with 256-bit GCM mode. */
119 MBEDTLS_CIPHER_CAMELLIA_128_ECB, /**< Camellia cipher with 128-bit ECB mode. */
120 MBEDTLS_CIPHER_CAMELLIA_192_ECB, /**< Camellia cipher with 192-bit ECB mode. */
121 MBEDTLS_CIPHER_CAMELLIA_256_ECB, /**< Camellia cipher with 256-bit ECB mode. */
122 MBEDTLS_CIPHER_CAMELLIA_128_CBC, /**< Camellia cipher with 128-bit CBC mode. */
123 MBEDTLS_CIPHER_CAMELLIA_192_CBC, /**< Camellia cipher with 192-bit CBC mode. */
124 MBEDTLS_CIPHER_CAMELLIA_256_CBC, /**< Camellia cipher with 256-bit CBC mode. */
125 MBEDTLS_CIPHER_CAMELLIA_128_CFB128, /**< Camellia cipher with 128-bit CFB128 mode. */
126 MBEDTLS_CIPHER_CAMELLIA_192_CFB128, /**< Camellia cipher with 192-bit CFB128 mode. */
127 MBEDTLS_CIPHER_CAMELLIA_256_CFB128, /**< Camellia cipher with 256-bit CFB128 mode. */
128 MBEDTLS_CIPHER_CAMELLIA_128_CTR, /**< Camellia cipher with 128-bit CTR mode. */
129 MBEDTLS_CIPHER_CAMELLIA_192_CTR, /**< Camellia cipher with 192-bit CTR mode. */
130 MBEDTLS_CIPHER_CAMELLIA_256_CTR, /**< Camellia cipher with 256-bit CTR mode. */
131 MBEDTLS_CIPHER_CAMELLIA_128_GCM, /**< Camellia cipher with 128-bit GCM mode. */
132 MBEDTLS_CIPHER_CAMELLIA_192_GCM, /**< Camellia cipher with 192-bit GCM mode. */
133 MBEDTLS_CIPHER_CAMELLIA_256_GCM, /**< Camellia cipher with 256-bit GCM mode. */
134 MBEDTLS_CIPHER_DES_ECB, /**< DES cipher with ECB mode. */
135 MBEDTLS_CIPHER_DES_CBC, /**< DES cipher with CBC mode. */
136 MBEDTLS_CIPHER_DES_EDE_ECB, /**< DES cipher with EDE ECB mode. */
137 MBEDTLS_CIPHER_DES_EDE_CBC, /**< DES cipher with EDE CBC mode. */
138 MBEDTLS_CIPHER_DES_EDE3_ECB, /**< DES cipher with EDE3 ECB mode. */
139 MBEDTLS_CIPHER_DES_EDE3_CBC, /**< DES cipher with EDE3 CBC mode. */
140 MBEDTLS_CIPHER_AES_128_CCM, /**< AES cipher with 128-bit CCM mode. */
141 MBEDTLS_CIPHER_AES_192_CCM, /**< AES cipher with 192-bit CCM mode. */
142 MBEDTLS_CIPHER_AES_256_CCM, /**< AES cipher with 256-bit CCM mode. */
143 MBEDTLS_CIPHER_AES_128_CCM_STAR_NO_TAG, /**< AES cipher with 128-bit CCM_STAR_NO_TAG mode. */
144 MBEDTLS_CIPHER_AES_192_CCM_STAR_NO_TAG, /**< AES cipher with 192-bit CCM_STAR_NO_TAG mode. */
145 MBEDTLS_CIPHER_AES_256_CCM_STAR_NO_TAG, /**< AES cipher with 256-bit CCM_STAR_NO_TAG mode. */
146 MBEDTLS_CIPHER_CAMELLIA_128_CCM, /**< Camellia cipher with 128-bit CCM mode. */
147 MBEDTLS_CIPHER_CAMELLIA_192_CCM, /**< Camellia cipher with 192-bit CCM mode. */
148 MBEDTLS_CIPHER_CAMELLIA_256_CCM, /**< Camellia cipher with 256-bit CCM mode. */
149 MBEDTLS_CIPHER_CAMELLIA_128_CCM_STAR_NO_TAG, /**< Camellia cipher with 128-bit CCM_STAR_NO_TAG mode. */
150 MBEDTLS_CIPHER_CAMELLIA_192_CCM_STAR_NO_TAG, /**< Camellia cipher with 192-bit CCM_STAR_NO_TAG mode. */
151 MBEDTLS_CIPHER_CAMELLIA_256_CCM_STAR_NO_TAG, /**< Camellia cipher with 256-bit CCM_STAR_NO_TAG mode. */
152 MBEDTLS_CIPHER_ARIA_128_ECB, /**< Aria cipher with 128-bit key and ECB mode. */
153 MBEDTLS_CIPHER_ARIA_192_ECB, /**< Aria cipher with 192-bit key and ECB mode. */
154 MBEDTLS_CIPHER_ARIA_256_ECB, /**< Aria cipher with 256-bit key and ECB mode. */
155 MBEDTLS_CIPHER_ARIA_128_CBC, /**< Aria cipher with 128-bit key and CBC mode. */
156 MBEDTLS_CIPHER_ARIA_192_CBC, /**< Aria cipher with 192-bit key and CBC mode. */
157 MBEDTLS_CIPHER_ARIA_256_CBC, /**< Aria cipher with 256-bit key and CBC mode. */
158 MBEDTLS_CIPHER_ARIA_128_CFB128, /**< Aria cipher with 128-bit key and CFB-128 mode. */
159 MBEDTLS_CIPHER_ARIA_192_CFB128, /**< Aria cipher with 192-bit key and CFB-128 mode. */
160 MBEDTLS_CIPHER_ARIA_256_CFB128, /**< Aria cipher with 256-bit key and CFB-128 mode. */
161 MBEDTLS_CIPHER_ARIA_128_CTR, /**< Aria cipher with 128-bit key and CTR mode. */
162 MBEDTLS_CIPHER_ARIA_192_CTR, /**< Aria cipher with 192-bit key and CTR mode. */
163 MBEDTLS_CIPHER_ARIA_256_CTR, /**< Aria cipher with 256-bit key and CTR mode. */
164 MBEDTLS_CIPHER_ARIA_128_GCM, /**< Aria cipher with 128-bit key and GCM mode. */
165 MBEDTLS_CIPHER_ARIA_192_GCM, /**< Aria cipher with 192-bit key and GCM mode. */
166 MBEDTLS_CIPHER_ARIA_256_GCM, /**< Aria cipher with 256-bit key and GCM mode. */
167 MBEDTLS_CIPHER_ARIA_128_CCM, /**< Aria cipher with 128-bit key and CCM mode. */
168 MBEDTLS_CIPHER_ARIA_192_CCM, /**< Aria cipher with 192-bit key and CCM mode. */
169 MBEDTLS_CIPHER_ARIA_256_CCM, /**< Aria cipher with 256-bit key and CCM mode. */
170 MBEDTLS_CIPHER_ARIA_128_CCM_STAR_NO_TAG, /**< Aria cipher with 128-bit key and CCM_STAR_NO_TAG mode. */
171 MBEDTLS_CIPHER_ARIA_192_CCM_STAR_NO_TAG, /**< Aria cipher with 192-bit key and CCM_STAR_NO_TAG mode. */
172 MBEDTLS_CIPHER_ARIA_256_CCM_STAR_NO_TAG, /**< Aria cipher with 256-bit key and CCM_STAR_NO_TAG mode. */
173 MBEDTLS_CIPHER_AES_128_OFB, /**< AES 128-bit cipher in OFB mode. */
174 MBEDTLS_CIPHER_AES_192_OFB, /**< AES 192-bit cipher in OFB mode. */
175 MBEDTLS_CIPHER_AES_256_OFB, /**< AES 256-bit cipher in OFB mode. */
176 MBEDTLS_CIPHER_AES_128_XTS, /**< AES 128-bit cipher in XTS block mode. */
177 MBEDTLS_CIPHER_AES_256_XTS, /**< AES 256-bit cipher in XTS block mode. */
178 MBEDTLS_CIPHER_CHACHA20, /**< ChaCha20 stream cipher. */
179 MBEDTLS_CIPHER_CHACHA20_POLY1305, /**< ChaCha20-Poly1305 AEAD cipher. */
180 MBEDTLS_CIPHER_AES_128_KW, /**< AES cipher with 128-bit NIST KW mode. */
181 MBEDTLS_CIPHER_AES_192_KW, /**< AES cipher with 192-bit NIST KW mode. */
182 MBEDTLS_CIPHER_AES_256_KW, /**< AES cipher with 256-bit NIST KW mode. */
183 MBEDTLS_CIPHER_AES_128_KWP, /**< AES cipher with 128-bit NIST KWP mode. */
184 MBEDTLS_CIPHER_AES_192_KWP, /**< AES cipher with 192-bit NIST KWP mode. */
185 MBEDTLS_CIPHER_AES_256_KWP, /**< AES cipher with 256-bit NIST KWP mode. */
186 } mbedtls_cipher_type_t;
187
188 /** Supported cipher modes. */
189 typedef enum {
190 MBEDTLS_MODE_NONE = 0, /**< None. */
191 MBEDTLS_MODE_ECB, /**< The ECB cipher mode. */
192 MBEDTLS_MODE_CBC, /**< The CBC cipher mode. */
193 MBEDTLS_MODE_CFB, /**< The CFB cipher mode. */
194 MBEDTLS_MODE_OFB, /**< The OFB cipher mode. */
195 MBEDTLS_MODE_CTR, /**< The CTR cipher mode. */
196 MBEDTLS_MODE_GCM, /**< The GCM cipher mode. */
197 MBEDTLS_MODE_STREAM, /**< The stream cipher mode. */
198 MBEDTLS_MODE_CCM, /**< The CCM cipher mode. */
199 MBEDTLS_MODE_CCM_STAR_NO_TAG, /**< The CCM*-no-tag cipher mode. */
200 MBEDTLS_MODE_XTS, /**< The XTS cipher mode. */
201 MBEDTLS_MODE_CHACHAPOLY, /**< The ChaCha-Poly cipher mode. */
202 MBEDTLS_MODE_KW, /**< The SP800-38F KW mode */
203 MBEDTLS_MODE_KWP, /**< The SP800-38F KWP mode */
204 } mbedtls_cipher_mode_t;
205
206 /** Supported cipher padding types. */
207 typedef enum {
208 MBEDTLS_PADDING_PKCS7 = 0, /**< PKCS7 padding (default). */
209 MBEDTLS_PADDING_ONE_AND_ZEROS, /**< ISO/IEC 7816-4 padding. */
210 MBEDTLS_PADDING_ZEROS_AND_LEN, /**< ANSI X.923 padding. */
211 MBEDTLS_PADDING_ZEROS, /**< Zero padding (not reversible). */
212 MBEDTLS_PADDING_NONE, /**< Never pad (full blocks only). */
213 } mbedtls_cipher_padding_t;
214
215 /** Type of operation. */
216 typedef enum {
217 MBEDTLS_OPERATION_NONE = -1,
218 MBEDTLS_DECRYPT = 0,
219 MBEDTLS_ENCRYPT,
220 } mbedtls_operation_t;
221
222 enum {
223 /** Undefined key length. */
224 MBEDTLS_KEY_LENGTH_NONE = 0,
225 /** Key length, in bits (including parity), for DES keys. */
226 MBEDTLS_KEY_LENGTH_DES = 64,
227 /** Key length in bits, including parity, for DES in two-key EDE. */
228 MBEDTLS_KEY_LENGTH_DES_EDE = 128,
229 /** Key length in bits, including parity, for DES in three-key EDE. */
230 MBEDTLS_KEY_LENGTH_DES_EDE3 = 192,
231 };
232
233 /** Maximum length of any IV, in Bytes. */
234 /* This should ideally be derived automatically from list of ciphers.
235 * This should be kept in sync with MBEDTLS_SSL_MAX_IV_LENGTH defined
236 * in library/ssl_misc.h. */
237 #define MBEDTLS_MAX_IV_LENGTH 16
238
239 /** Maximum block size of any cipher, in Bytes. */
240 /* This should ideally be derived automatically from list of ciphers.
241 * This should be kept in sync with MBEDTLS_SSL_MAX_BLOCK_LENGTH defined
242 * in library/ssl_misc.h. */
243 #define MBEDTLS_MAX_BLOCK_LENGTH 16
244
245 /** Maximum key length, in Bytes. */
246 /* This should ideally be derived automatically from list of ciphers.
247 * For now, only check whether XTS is enabled which uses 64 Byte keys,
248 * and use 32 Bytes as an upper bound for the maximum key length otherwise.
249 * This should be kept in sync with MBEDTLS_SSL_MAX_BLOCK_LENGTH defined
250 * in library/ssl_misc.h, which however deliberately ignores the case of XTS
251 * since the latter isn't used in SSL/TLS. */
252 #if defined(MBEDTLS_CIPHER_MODE_XTS)
253 #define MBEDTLS_MAX_KEY_LENGTH 64
254 #else
255 #define MBEDTLS_MAX_KEY_LENGTH 32
256 #endif /* MBEDTLS_CIPHER_MODE_XTS */
257
258 /**
259 * Base cipher information (opaque struct).
260 */
261 typedef struct mbedtls_cipher_base_t mbedtls_cipher_base_t;
262
263 /**
264 * CMAC context (opaque struct).
265 */
266 typedef struct mbedtls_cmac_context_t mbedtls_cmac_context_t;
267
268 /**
269 * Cipher information. Allows calling cipher functions
270 * in a generic way.
271 *
272 * \note The library does not support custom cipher info structures,
273 * only built-in structures returned by the functions
274 * mbedtls_cipher_info_from_string(),
275 * mbedtls_cipher_info_from_type(),
276 * mbedtls_cipher_info_from_values(),
277 * mbedtls_cipher_info_from_psa().
278 */
279 typedef struct mbedtls_cipher_info_t
280 {
281 /** Full cipher identifier. For example,
282 * MBEDTLS_CIPHER_AES_256_CBC.
283 */
284 mbedtls_cipher_type_t MBEDTLS_PRIVATE(type);
285
286 /** The cipher mode. For example, MBEDTLS_MODE_CBC. */
287 mbedtls_cipher_mode_t MBEDTLS_PRIVATE(mode);
288
289 /** The cipher key length, in bits. This is the
290 * default length for variable sized ciphers.
291 * Includes parity bits for ciphers like DES.
292 */
293 unsigned int MBEDTLS_PRIVATE(key_bitlen);
294
295 /** Name of the cipher. */
296 const char * MBEDTLS_PRIVATE(name);
297
298 /** IV or nonce size, in Bytes.
299 * For ciphers that accept variable IV sizes,
300 * this is the recommended size.
301 */
302 unsigned int MBEDTLS_PRIVATE(iv_size);
303
304 /** Bitflag comprised of MBEDTLS_CIPHER_VARIABLE_IV_LEN and
305 * MBEDTLS_CIPHER_VARIABLE_KEY_LEN indicating whether the
306 * cipher supports variable IV or variable key sizes, respectively.
307 */
308 int MBEDTLS_PRIVATE(flags);
309
310 /** The block size, in Bytes. */
311 unsigned int MBEDTLS_PRIVATE(block_size);
312
313 /** Struct for base cipher information and functions. */
314 const mbedtls_cipher_base_t *MBEDTLS_PRIVATE(base);
315
316 } mbedtls_cipher_info_t;
317
318 /**
319 * Generic cipher context.
320 */
321 typedef struct mbedtls_cipher_context_t
322 {
323 /** Information about the associated cipher. */
324 const mbedtls_cipher_info_t *MBEDTLS_PRIVATE(cipher_info);
325
326 /** Key length to use. */
327 int MBEDTLS_PRIVATE(key_bitlen);
328
329 /** Operation that the key of the context has been
330 * initialized for.
331 */
332 mbedtls_operation_t MBEDTLS_PRIVATE(operation);
333
334 #if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
335 /** Padding functions to use, if relevant for
336 * the specific cipher mode.
337 */
338 void (*MBEDTLS_PRIVATE(add_padding))( unsigned char *output, size_t olen, size_t data_len );
339 int (*MBEDTLS_PRIVATE(get_padding))( unsigned char *input, size_t ilen, size_t *data_len );
340 #endif
341
342 /** Buffer for input that has not been processed yet. */
343 unsigned char MBEDTLS_PRIVATE(unprocessed_data)[MBEDTLS_MAX_BLOCK_LENGTH];
344
345 /** Number of Bytes that have not been processed yet. */
346 size_t MBEDTLS_PRIVATE(unprocessed_len);
347
348 /** Current IV or NONCE_COUNTER for CTR-mode, data unit (or sector) number
349 * for XTS-mode. */
350 unsigned char MBEDTLS_PRIVATE(iv)[MBEDTLS_MAX_IV_LENGTH];
351
352 /** IV size in Bytes, for ciphers with variable-length IVs. */
353 size_t MBEDTLS_PRIVATE(iv_size);
354
355 /** The cipher-specific context. */
356 void *MBEDTLS_PRIVATE(cipher_ctx);
357
358 #if defined(MBEDTLS_CMAC_C)
359 /** CMAC-specific context. */
360 mbedtls_cmac_context_t *MBEDTLS_PRIVATE(cmac_ctx);
361 #endif
362
363 #if defined(MBEDTLS_USE_PSA_CRYPTO)
364 /** Indicates whether the cipher operations should be performed
365 * by Mbed TLS' own crypto library or an external implementation
366 * of the PSA Crypto API.
367 * This is unset if the cipher context was established through
368 * mbedtls_cipher_setup(), and set if it was established through
369 * mbedtls_cipher_setup_psa().
370 */
371 unsigned char MBEDTLS_PRIVATE(psa_enabled);
372 #endif /* MBEDTLS_USE_PSA_CRYPTO */
373
374 } mbedtls_cipher_context_t;
375
376 /**
377 * \brief This function retrieves the list of ciphers supported
378 * by the generic cipher module.
379 *
380 * For any cipher identifier in the returned list, you can
381 * obtain the corresponding generic cipher information structure
382 * via mbedtls_cipher_info_from_type(), which can then be used
383 * to prepare a cipher context via mbedtls_cipher_setup().
384 *
385 *
386 * \return A statically-allocated array of cipher identifiers
387 * of type cipher_type_t. The last entry is zero.
388 */
389 const int *mbedtls_cipher_list( void );
390
391 /**
392 * \brief This function retrieves the cipher-information
393 * structure associated with the given cipher name.
394 *
395 * \param cipher_name Name of the cipher to search for. This must not be
396 * \c NULL.
397 *
398 * \return The cipher information structure associated with the
399 * given \p cipher_name.
400 * \return \c NULL if the associated cipher information is not found.
401 */
402 const mbedtls_cipher_info_t *mbedtls_cipher_info_from_string( const char *cipher_name );
403
404 /**
405 * \brief This function retrieves the cipher-information
406 * structure associated with the given cipher type.
407 *
408 * \param cipher_type Type of the cipher to search for.
409 *
410 * \return The cipher information structure associated with the
411 * given \p cipher_type.
412 * \return \c NULL if the associated cipher information is not found.
413 */
414 const mbedtls_cipher_info_t *mbedtls_cipher_info_from_type( const mbedtls_cipher_type_t cipher_type );
415
416 /**
417 * \brief This function retrieves the cipher-information
418 * structure associated with the given cipher ID,
419 * key size and mode.
420 *
421 * \param cipher_id The ID of the cipher to search for. For example,
422 * #MBEDTLS_CIPHER_ID_AES.
423 * \param key_bitlen The length of the key in bits.
424 * \param mode The cipher mode. For example, #MBEDTLS_MODE_CBC.
425 *
426 * \return The cipher information structure associated with the
427 * given \p cipher_id.
428 * \return \c NULL if the associated cipher information is not found.
429 */
430 const mbedtls_cipher_info_t *mbedtls_cipher_info_from_values( const mbedtls_cipher_id_t cipher_id,
431 int key_bitlen,
432 const mbedtls_cipher_mode_t mode );
433
434 /**
435 * \brief Retrieve the identifier for a cipher info structure.
436 *
437 * \param[in] info The cipher info structure to query.
438 * This may be \c NULL.
439 *
440 * \return The full cipher identifier (\c MBEDTLS_CIPHER_xxx).
441 * \return #MBEDTLS_CIPHER_NONE if \p info is \c NULL.
442 */
mbedtls_cipher_info_get_type(const mbedtls_cipher_info_t * info)443 static inline mbedtls_cipher_type_t mbedtls_cipher_info_get_type(
444 const mbedtls_cipher_info_t *info )
445 {
446 if( info == NULL )
447 return( MBEDTLS_CIPHER_NONE );
448 else
449 return( info->MBEDTLS_PRIVATE(type) );
450 }
451
452 /**
453 * \brief Retrieve the operation mode for a cipher info structure.
454 *
455 * \param[in] info The cipher info structure to query.
456 * This may be \c NULL.
457 *
458 * \return The cipher mode (\c MBEDTLS_MODE_xxx).
459 * \return #MBEDTLS_MODE_NONE if \p info is \c NULL.
460 */
mbedtls_cipher_info_get_mode(const mbedtls_cipher_info_t * info)461 static inline mbedtls_cipher_mode_t mbedtls_cipher_info_get_mode(
462 const mbedtls_cipher_info_t *info )
463 {
464 if( info == NULL )
465 return( MBEDTLS_MODE_NONE );
466 else
467 return( info->MBEDTLS_PRIVATE(mode) );
468 }
469
470 /**
471 * \brief Retrieve the key size for a cipher info structure.
472 *
473 * \param[in] info The cipher info structure to query.
474 * This may be \c NULL.
475 *
476 * \return The key length in bits.
477 * For variable-sized ciphers, this is the default length.
478 * For DES, this includes the parity bits.
479 * \return \c 0 if \p info is \c NULL.
480 */
mbedtls_cipher_info_get_key_bitlen(const mbedtls_cipher_info_t * info)481 static inline size_t mbedtls_cipher_info_get_key_bitlen(
482 const mbedtls_cipher_info_t *info )
483 {
484 if( info == NULL )
485 return( 0 );
486 else
487 return( info->MBEDTLS_PRIVATE(key_bitlen) );
488 }
489
490 /**
491 * \brief Retrieve the human-readable name for a
492 * cipher info structure.
493 *
494 * \param[in] info The cipher info structure to query.
495 * This may be \c NULL.
496 *
497 * \return The cipher name, which is a human readable string,
498 * with static storage duration.
499 * \return \c NULL if \c info is \p NULL.
500 */
mbedtls_cipher_info_get_name(const mbedtls_cipher_info_t * info)501 static inline const char *mbedtls_cipher_info_get_name(
502 const mbedtls_cipher_info_t *info )
503 {
504 if( info == NULL )
505 return( NULL );
506 else
507 return( info->MBEDTLS_PRIVATE(name) );
508 }
509
510 /**
511 * \brief This function initializes a \p cipher_context as NONE.
512 *
513 * \param ctx The context to be initialized. This must not be \c NULL.
514 */
515 void mbedtls_cipher_init( mbedtls_cipher_context_t *ctx );
516
517 /**
518 * \brief This function frees and clears the cipher-specific
519 * context of \p ctx. Freeing \p ctx itself remains the
520 * responsibility of the caller.
521 *
522 * \param ctx The context to be freed. If this is \c NULL, the
523 * function has no effect, otherwise this must point to an
524 * initialized context.
525 */
526 void mbedtls_cipher_free( mbedtls_cipher_context_t *ctx );
527
528
529 /**
530 * \brief This function prepares a cipher context for
531 * use with the given cipher primitive.
532 *
533 * \note After calling this function, you should call
534 * mbedtls_cipher_setkey() and, if the mode uses padding,
535 * mbedtls_cipher_set_padding_mode(), then for each
536 * message to encrypt or decrypt with this key, either:
537 * - mbedtls_cipher_crypt() for one-shot processing with
538 * non-AEAD modes;
539 * - mbedtls_cipher_auth_encrypt_ext() or
540 * mbedtls_cipher_auth_decrypt_ext() for one-shot
541 * processing with AEAD modes or NIST_KW;
542 * - for multi-part processing, see the documentation of
543 * mbedtls_cipher_reset().
544 *
545 * \param ctx The context to prepare. This must be initialized by
546 * a call to mbedtls_cipher_init() first.
547 * \param cipher_info The cipher to use.
548 *
549 * \return \c 0 on success.
550 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
551 * parameter-verification failure.
552 * \return #MBEDTLS_ERR_CIPHER_ALLOC_FAILED if allocation of the
553 * cipher-specific context fails.
554 */
555 int mbedtls_cipher_setup( mbedtls_cipher_context_t *ctx,
556 const mbedtls_cipher_info_t *cipher_info );
557
558 #if defined(MBEDTLS_USE_PSA_CRYPTO)
559 /**
560 * \brief This function initializes a cipher context for
561 * PSA-based use with the given cipher primitive.
562 *
563 * \note See #MBEDTLS_USE_PSA_CRYPTO for information on PSA.
564 *
565 * \param ctx The context to initialize. May not be \c NULL.
566 * \param cipher_info The cipher to use.
567 * \param taglen For AEAD ciphers, the length in bytes of the
568 * authentication tag to use. Subsequent uses of
569 * mbedtls_cipher_auth_encrypt_ext() or
570 * mbedtls_cipher_auth_decrypt_ext() must provide
571 * the same tag length.
572 * For non-AEAD ciphers, the value must be \c 0.
573 *
574 * \return \c 0 on success.
575 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
576 * parameter-verification failure.
577 * \return #MBEDTLS_ERR_CIPHER_ALLOC_FAILED if allocation of the
578 * cipher-specific context fails.
579 */
580 int mbedtls_cipher_setup_psa( mbedtls_cipher_context_t *ctx,
581 const mbedtls_cipher_info_t *cipher_info,
582 size_t taglen );
583 #endif /* MBEDTLS_USE_PSA_CRYPTO */
584
585 /**
586 * \brief This function returns the block size of the given cipher.
587 *
588 * \param ctx The context of the cipher. This must be initialized.
589 *
590 * \return The block size of the underlying cipher.
591 * \return \c 0 if \p ctx has not been initialized.
592 */
mbedtls_cipher_get_block_size(const mbedtls_cipher_context_t * ctx)593 static inline unsigned int mbedtls_cipher_get_block_size(
594 const mbedtls_cipher_context_t *ctx )
595 {
596 MBEDTLS_INTERNAL_VALIDATE_RET( ctx != NULL, 0 );
597 if( ctx->MBEDTLS_PRIVATE(cipher_info) == NULL )
598 return 0;
599
600 return ctx->MBEDTLS_PRIVATE(cipher_info)->MBEDTLS_PRIVATE(block_size);
601 }
602
603 /**
604 * \brief This function returns the mode of operation for
605 * the cipher. For example, MBEDTLS_MODE_CBC.
606 *
607 * \param ctx The context of the cipher. This must be initialized.
608 *
609 * \return The mode of operation.
610 * \return #MBEDTLS_MODE_NONE if \p ctx has not been initialized.
611 */
mbedtls_cipher_get_cipher_mode(const mbedtls_cipher_context_t * ctx)612 static inline mbedtls_cipher_mode_t mbedtls_cipher_get_cipher_mode(
613 const mbedtls_cipher_context_t *ctx )
614 {
615 MBEDTLS_INTERNAL_VALIDATE_RET( ctx != NULL, MBEDTLS_MODE_NONE );
616 if( ctx->MBEDTLS_PRIVATE(cipher_info) == NULL )
617 return MBEDTLS_MODE_NONE;
618
619 return ctx->MBEDTLS_PRIVATE(cipher_info)->MBEDTLS_PRIVATE(mode);
620 }
621
622 /**
623 * \brief This function returns the size of the IV or nonce
624 * of the cipher, in Bytes.
625 *
626 * \param ctx The context of the cipher. This must be initialized.
627 *
628 * \return The recommended IV size if no IV has been set.
629 * \return \c 0 for ciphers not using an IV or a nonce.
630 * \return The actual size if an IV has been set.
631 */
mbedtls_cipher_get_iv_size(const mbedtls_cipher_context_t * ctx)632 static inline int mbedtls_cipher_get_iv_size(
633 const mbedtls_cipher_context_t *ctx )
634 {
635 MBEDTLS_INTERNAL_VALIDATE_RET( ctx != NULL, 0 );
636 if( ctx->MBEDTLS_PRIVATE(cipher_info) == NULL )
637 return 0;
638
639 if( ctx->MBEDTLS_PRIVATE(iv_size) != 0 )
640 return (int) ctx->MBEDTLS_PRIVATE(iv_size);
641
642 return (int) ctx->MBEDTLS_PRIVATE(cipher_info)->MBEDTLS_PRIVATE(iv_size);
643 }
644
645 /**
646 * \brief This function returns the type of the given cipher.
647 *
648 * \param ctx The context of the cipher. This must be initialized.
649 *
650 * \return The type of the cipher.
651 * \return #MBEDTLS_CIPHER_NONE if \p ctx has not been initialized.
652 */
mbedtls_cipher_get_type(const mbedtls_cipher_context_t * ctx)653 static inline mbedtls_cipher_type_t mbedtls_cipher_get_type(
654 const mbedtls_cipher_context_t *ctx )
655 {
656 MBEDTLS_INTERNAL_VALIDATE_RET(
657 ctx != NULL, MBEDTLS_CIPHER_NONE );
658 if( ctx->MBEDTLS_PRIVATE(cipher_info) == NULL )
659 return MBEDTLS_CIPHER_NONE;
660
661 return ctx->MBEDTLS_PRIVATE(cipher_info)->MBEDTLS_PRIVATE(type);
662 }
663
664 /**
665 * \brief This function returns the name of the given cipher
666 * as a string.
667 *
668 * \param ctx The context of the cipher. This must be initialized.
669 *
670 * \return The name of the cipher.
671 * \return NULL if \p ctx has not been not initialized.
672 */
mbedtls_cipher_get_name(const mbedtls_cipher_context_t * ctx)673 static inline const char *mbedtls_cipher_get_name(
674 const mbedtls_cipher_context_t *ctx )
675 {
676 MBEDTLS_INTERNAL_VALIDATE_RET( ctx != NULL, 0 );
677 if( ctx->MBEDTLS_PRIVATE(cipher_info) == NULL )
678 return 0;
679
680 return ctx->MBEDTLS_PRIVATE(cipher_info)->MBEDTLS_PRIVATE(name);
681 }
682
683 /**
684 * \brief This function returns the key length of the cipher.
685 *
686 * \param ctx The context of the cipher. This must be initialized.
687 *
688 * \return The key length of the cipher in bits.
689 * \return #MBEDTLS_KEY_LENGTH_NONE if ctx \p has not been
690 * initialized.
691 */
mbedtls_cipher_get_key_bitlen(const mbedtls_cipher_context_t * ctx)692 static inline int mbedtls_cipher_get_key_bitlen(
693 const mbedtls_cipher_context_t *ctx )
694 {
695 MBEDTLS_INTERNAL_VALIDATE_RET(
696 ctx != NULL, MBEDTLS_KEY_LENGTH_NONE );
697 if( ctx->MBEDTLS_PRIVATE(cipher_info) == NULL )
698 return MBEDTLS_KEY_LENGTH_NONE;
699
700 return (int) ctx->MBEDTLS_PRIVATE(cipher_info)->MBEDTLS_PRIVATE(key_bitlen);
701 }
702
703 /**
704 * \brief This function returns the operation of the given cipher.
705 *
706 * \param ctx The context of the cipher. This must be initialized.
707 *
708 * \return The type of operation: #MBEDTLS_ENCRYPT or #MBEDTLS_DECRYPT.
709 * \return #MBEDTLS_OPERATION_NONE if \p ctx has not been initialized.
710 */
mbedtls_cipher_get_operation(const mbedtls_cipher_context_t * ctx)711 static inline mbedtls_operation_t mbedtls_cipher_get_operation(
712 const mbedtls_cipher_context_t *ctx )
713 {
714 MBEDTLS_INTERNAL_VALIDATE_RET(
715 ctx != NULL, MBEDTLS_OPERATION_NONE );
716 if( ctx->MBEDTLS_PRIVATE(cipher_info) == NULL )
717 return MBEDTLS_OPERATION_NONE;
718
719 return ctx->MBEDTLS_PRIVATE(operation);
720 }
721
722 /**
723 * \brief This function sets the key to use with the given context.
724 *
725 * \param ctx The generic cipher context. This must be initialized and
726 * bound to a cipher information structure.
727 * \param key The key to use. This must be a readable buffer of at
728 * least \p key_bitlen Bits.
729 * \param key_bitlen The key length to use, in Bits.
730 * \param operation The operation that the key will be used for:
731 * #MBEDTLS_ENCRYPT or #MBEDTLS_DECRYPT.
732 *
733 * \return \c 0 on success.
734 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
735 * parameter-verification failure.
736 * \return A cipher-specific error code on failure.
737 */
738 int mbedtls_cipher_setkey( mbedtls_cipher_context_t *ctx,
739 const unsigned char *key,
740 int key_bitlen,
741 const mbedtls_operation_t operation );
742
743 #if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
744 /**
745 * \brief This function sets the padding mode, for cipher modes
746 * that use padding.
747 *
748 * The default passing mode is PKCS7 padding.
749 *
750 * \param ctx The generic cipher context. This must be initialized and
751 * bound to a cipher information structure.
752 * \param mode The padding mode.
753 *
754 * \return \c 0 on success.
755 * \return #MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE
756 * if the selected padding mode is not supported.
757 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if the cipher mode
758 * does not support padding.
759 */
760 int mbedtls_cipher_set_padding_mode( mbedtls_cipher_context_t *ctx,
761 mbedtls_cipher_padding_t mode );
762 #endif /* MBEDTLS_CIPHER_MODE_WITH_PADDING */
763
764 /**
765 * \brief This function sets the initialization vector (IV)
766 * or nonce.
767 *
768 * \note Some ciphers do not use IVs nor nonce. For these
769 * ciphers, this function has no effect.
770 *
771 * \param ctx The generic cipher context. This must be initialized and
772 * bound to a cipher information structure.
773 * \param iv The IV to use, or NONCE_COUNTER for CTR-mode ciphers. This
774 * must be a readable buffer of at least \p iv_len Bytes.
775 * \param iv_len The IV length for ciphers with variable-size IV.
776 * This parameter is discarded by ciphers with fixed-size IV.
777 *
778 * \return \c 0 on success.
779 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
780 * parameter-verification failure.
781 */
782 int mbedtls_cipher_set_iv( mbedtls_cipher_context_t *ctx,
783 const unsigned char *iv,
784 size_t iv_len );
785
786 /**
787 * \brief This function resets the cipher state.
788 *
789 * \note With non-AEAD ciphers, the order of calls for each message
790 * is as follows:
791 * 1. mbedtls_cipher_set_iv() if the mode uses an IV/nonce.
792 * 2. mbedtls_cipher_reset()
793 * 3. mbedtls_cipher_update() one or more times
794 * 4. mbedtls_cipher_finish()
795 * .
796 * This sequence can be repeated to encrypt or decrypt multiple
797 * messages with the same key.
798 *
799 * \note With AEAD ciphers, the order of calls for each message
800 * is as follows:
801 * 1. mbedtls_cipher_set_iv() if the mode uses an IV/nonce.
802 * 2. mbedtls_cipher_reset()
803 * 3. mbedtls_cipher_update_ad()
804 * 4. mbedtls_cipher_update() one or more times
805 * 5. mbedtls_cipher_finish()
806 * 6. mbedtls_cipher_check_tag() (for decryption) or
807 * mbedtls_cipher_write_tag() (for encryption).
808 * .
809 * This sequence can be repeated to encrypt or decrypt multiple
810 * messages with the same key.
811 *
812 * \param ctx The generic cipher context. This must be bound to a key.
813 *
814 * \return \c 0 on success.
815 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
816 * parameter-verification failure.
817 */
818 int mbedtls_cipher_reset( mbedtls_cipher_context_t *ctx );
819
820 #if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CHACHAPOLY_C)
821 /**
822 * \brief This function adds additional data for AEAD ciphers.
823 * Currently supported with GCM and ChaCha20+Poly1305.
824 *
825 * \param ctx The generic cipher context. This must be initialized.
826 * \param ad The additional data to use. This must be a readable
827 * buffer of at least \p ad_len Bytes.
828 * \param ad_len The length of \p ad in Bytes.
829 *
830 * \return \c 0 on success.
831 * \return A specific error code on failure.
832 */
833 int mbedtls_cipher_update_ad( mbedtls_cipher_context_t *ctx,
834 const unsigned char *ad, size_t ad_len );
835 #endif /* MBEDTLS_GCM_C || MBEDTLS_CHACHAPOLY_C */
836
837 /**
838 * \brief The generic cipher update function. It encrypts or
839 * decrypts using the given cipher context. Writes as
840 * many block-sized blocks of data as possible to output.
841 * Any data that cannot be written immediately is either
842 * added to the next block, or flushed when
843 * mbedtls_cipher_finish() is called.
844 * Exception: For MBEDTLS_MODE_ECB, expects a single block
845 * in size. For example, 16 Bytes for AES.
846 *
847 * \param ctx The generic cipher context. This must be initialized and
848 * bound to a key.
849 * \param input The buffer holding the input data. This must be a
850 * readable buffer of at least \p ilen Bytes.
851 * \param ilen The length of the input data.
852 * \param output The buffer for the output data. This must be able to
853 * hold at least `ilen + block_size`. This must not be the
854 * same buffer as \p input.
855 * \param olen The length of the output data, to be updated with the
856 * actual number of Bytes written. This must not be
857 * \c NULL.
858 *
859 * \return \c 0 on success.
860 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
861 * parameter-verification failure.
862 * \return #MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE on an
863 * unsupported mode for a cipher.
864 * \return A cipher-specific error code on failure.
865 */
866 int mbedtls_cipher_update( mbedtls_cipher_context_t *ctx,
867 const unsigned char *input,
868 size_t ilen, unsigned char *output,
869 size_t *olen );
870
871 /**
872 * \brief The generic cipher finalization function. If data still
873 * needs to be flushed from an incomplete block, the data
874 * contained in it is padded to the size of
875 * the last block, and written to the \p output buffer.
876 *
877 * \param ctx The generic cipher context. This must be initialized and
878 * bound to a key.
879 * \param output The buffer to write data to. This needs to be a writable
880 * buffer of at least \p block_size Bytes.
881 * \param olen The length of the data written to the \p output buffer.
882 * This may not be \c NULL.
883 *
884 * \return \c 0 on success.
885 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
886 * parameter-verification failure.
887 * \return #MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED on decryption
888 * expecting a full block but not receiving one.
889 * \return #MBEDTLS_ERR_CIPHER_INVALID_PADDING on invalid padding
890 * while decrypting.
891 * \return A cipher-specific error code on failure.
892 */
893 int mbedtls_cipher_finish( mbedtls_cipher_context_t *ctx,
894 unsigned char *output, size_t *olen );
895
896 #if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CHACHAPOLY_C)
897 /**
898 * \brief This function writes a tag for AEAD ciphers.
899 * Currently supported with GCM and ChaCha20+Poly1305.
900 * This must be called after mbedtls_cipher_finish().
901 *
902 * \param ctx The generic cipher context. This must be initialized,
903 * bound to a key, and have just completed a cipher
904 * operation through mbedtls_cipher_finish() the tag for
905 * which should be written.
906 * \param tag The buffer to write the tag to. This must be a writable
907 * buffer of at least \p tag_len Bytes.
908 * \param tag_len The length of the tag to write.
909 *
910 * \return \c 0 on success.
911 * \return A specific error code on failure.
912 */
913 int mbedtls_cipher_write_tag( mbedtls_cipher_context_t *ctx,
914 unsigned char *tag, size_t tag_len );
915
916 /**
917 * \brief This function checks the tag for AEAD ciphers.
918 * Currently supported with GCM and ChaCha20+Poly1305.
919 * This must be called after mbedtls_cipher_finish().
920 *
921 * \param ctx The generic cipher context. This must be initialized.
922 * \param tag The buffer holding the tag. This must be a readable
923 * buffer of at least \p tag_len Bytes.
924 * \param tag_len The length of the tag to check.
925 *
926 * \return \c 0 on success.
927 * \return A specific error code on failure.
928 */
929 int mbedtls_cipher_check_tag( mbedtls_cipher_context_t *ctx,
930 const unsigned char *tag, size_t tag_len );
931 #endif /* MBEDTLS_GCM_C || MBEDTLS_CHACHAPOLY_C */
932
933 /**
934 * \brief The generic all-in-one encryption/decryption function,
935 * for all ciphers except AEAD constructs.
936 *
937 * \param ctx The generic cipher context. This must be initialized.
938 * \param iv The IV to use, or NONCE_COUNTER for CTR-mode ciphers.
939 * This must be a readable buffer of at least \p iv_len
940 * Bytes.
941 * \param iv_len The IV length for ciphers with variable-size IV.
942 * This parameter is discarded by ciphers with fixed-size
943 * IV.
944 * \param input The buffer holding the input data. This must be a
945 * readable buffer of at least \p ilen Bytes.
946 * \param ilen The length of the input data in Bytes.
947 * \param output The buffer for the output data. This must be able to
948 * hold at least `ilen + block_size`. This must not be the
949 * same buffer as \p input.
950 * \param olen The length of the output data, to be updated with the
951 * actual number of Bytes written. This must not be
952 * \c NULL.
953 *
954 * \note Some ciphers do not use IVs nor nonce. For these
955 * ciphers, use \p iv = NULL and \p iv_len = 0.
956 *
957 * \return \c 0 on success.
958 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
959 * parameter-verification failure.
960 * \return #MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED on decryption
961 * expecting a full block but not receiving one.
962 * \return #MBEDTLS_ERR_CIPHER_INVALID_PADDING on invalid padding
963 * while decrypting.
964 * \return A cipher-specific error code on failure.
965 */
966 int mbedtls_cipher_crypt( mbedtls_cipher_context_t *ctx,
967 const unsigned char *iv, size_t iv_len,
968 const unsigned char *input, size_t ilen,
969 unsigned char *output, size_t *olen );
970
971 #if defined(MBEDTLS_CIPHER_MODE_AEAD) || defined(MBEDTLS_NIST_KW_C)
972 /**
973 * \brief The authenticated encryption (AEAD/NIST_KW) function.
974 *
975 * \note For AEAD modes, the tag will be appended to the
976 * ciphertext, as recommended by RFC 5116.
977 * (NIST_KW doesn't have a separate tag.)
978 *
979 * \param ctx The generic cipher context. This must be initialized and
980 * bound to a key, with an AEAD algorithm or NIST_KW.
981 * \param iv The nonce to use. This must be a readable buffer of
982 * at least \p iv_len Bytes and may be \c NULL if \p
983 * iv_len is \c 0.
984 * \param iv_len The length of the nonce. For AEAD ciphers, this must
985 * satisfy the constraints imposed by the cipher used.
986 * For NIST_KW, this must be \c 0.
987 * \param ad The additional data to authenticate. This must be a
988 * readable buffer of at least \p ad_len Bytes, and may
989 * be \c NULL is \p ad_len is \c 0.
990 * \param ad_len The length of \p ad. For NIST_KW, this must be \c 0.
991 * \param input The buffer holding the input data. This must be a
992 * readable buffer of at least \p ilen Bytes, and may be
993 * \c NULL if \p ilen is \c 0.
994 * \param ilen The length of the input data.
995 * \param output The buffer for the output data. This must be a
996 * writable buffer of at least \p output_len Bytes, and
997 * must not be \c NULL.
998 * \param output_len The length of the \p output buffer in Bytes. For AEAD
999 * ciphers, this must be at least \p ilen + \p tag_len.
1000 * For NIST_KW, this must be at least \p ilen + 8
1001 * (rounded up to a multiple of 8 if KWP is used);
1002 * \p ilen + 15 is always a safe value.
1003 * \param olen This will be filled with the actual number of Bytes
1004 * written to the \p output buffer. This must point to a
1005 * writable object of type \c size_t.
1006 * \param tag_len The desired length of the authentication tag. For AEAD
1007 * ciphers, this must match the constraints imposed by
1008 * the cipher used, and in particular must not be \c 0.
1009 * For NIST_KW, this must be \c 0.
1010 *
1011 * \return \c 0 on success.
1012 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
1013 * parameter-verification failure.
1014 * \return A cipher-specific error code on failure.
1015 */
1016 int mbedtls_cipher_auth_encrypt_ext( mbedtls_cipher_context_t *ctx,
1017 const unsigned char *iv, size_t iv_len,
1018 const unsigned char *ad, size_t ad_len,
1019 const unsigned char *input, size_t ilen,
1020 unsigned char *output, size_t output_len,
1021 size_t *olen, size_t tag_len );
1022
1023 /**
1024 * \brief The authenticated encryption (AEAD/NIST_KW) function.
1025 *
1026 * \note If the data is not authentic, then the output buffer
1027 * is zeroed out to prevent the unauthentic plaintext being
1028 * used, making this interface safer.
1029 *
1030 * \note For AEAD modes, the tag must be appended to the
1031 * ciphertext, as recommended by RFC 5116.
1032 * (NIST_KW doesn't have a separate tag.)
1033 *
1034 * \param ctx The generic cipher context. This must be initialized and
1035 * bound to a key, with an AEAD algorithm or NIST_KW.
1036 * \param iv The nonce to use. This must be a readable buffer of
1037 * at least \p iv_len Bytes and may be \c NULL if \p
1038 * iv_len is \c 0.
1039 * \param iv_len The length of the nonce. For AEAD ciphers, this must
1040 * satisfy the constraints imposed by the cipher used.
1041 * For NIST_KW, this must be \c 0.
1042 * \param ad The additional data to authenticate. This must be a
1043 * readable buffer of at least \p ad_len Bytes, and may
1044 * be \c NULL is \p ad_len is \c 0.
1045 * \param ad_len The length of \p ad. For NIST_KW, this must be \c 0.
1046 * \param input The buffer holding the input data. This must be a
1047 * readable buffer of at least \p ilen Bytes, and may be
1048 * \c NULL if \p ilen is \c 0.
1049 * \param ilen The length of the input data. For AEAD ciphers this
1050 * must be at least \p tag_len. For NIST_KW this must be
1051 * at least \c 8.
1052 * \param output The buffer for the output data. This must be a
1053 * writable buffer of at least \p output_len Bytes, and
1054 * may be \c NULL if \p output_len is \c 0.
1055 * \param output_len The length of the \p output buffer in Bytes. For AEAD
1056 * ciphers, this must be at least \p ilen - \p tag_len.
1057 * For NIST_KW, this must be at least \p ilen - 8.
1058 * \param olen This will be filled with the actual number of Bytes
1059 * written to the \p output buffer. This must point to a
1060 * writable object of type \c size_t.
1061 * \param tag_len The actual length of the authentication tag. For AEAD
1062 * ciphers, this must match the constraints imposed by
1063 * the cipher used, and in particular must not be \c 0.
1064 * For NIST_KW, this must be \c 0.
1065 *
1066 * \return \c 0 on success.
1067 * \return #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on
1068 * parameter-verification failure.
1069 * \return #MBEDTLS_ERR_CIPHER_AUTH_FAILED if data is not authentic.
1070 * \return A cipher-specific error code on failure.
1071 */
1072 int mbedtls_cipher_auth_decrypt_ext( mbedtls_cipher_context_t *ctx,
1073 const unsigned char *iv, size_t iv_len,
1074 const unsigned char *ad, size_t ad_len,
1075 const unsigned char *input, size_t ilen,
1076 unsigned char *output, size_t output_len,
1077 size_t *olen, size_t tag_len );
1078 #endif /* MBEDTLS_CIPHER_MODE_AEAD || MBEDTLS_NIST_KW_C */
1079 #ifdef __cplusplus
1080 }
1081 #endif
1082
1083 #endif /* MBEDTLS_CIPHER_H */
1084