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1 /**
2  * \file psa/crypto_struct.h
3  *
4  * \brief PSA cryptography module: Mbed TLS structured type implementations
5  *
6  * \note This file may not be included directly. Applications must
7  * include psa/crypto.h.
8  *
9  * This file contains the definitions of some data structures with
10  * implementation-specific definitions.
11  *
12  * In implementations with isolation between the application and the
13  * cryptography module, it is expected that the front-end and the back-end
14  * would have different versions of this file.
15  *
16  * <h3>Design notes about multipart operation structures</h3>
17  *
18  * For multipart operations without driver delegation support, each multipart
19  * operation structure contains a `psa_algorithm_t alg` field which indicates
20  * which specific algorithm the structure is for. When the structure is not in
21  * use, `alg` is 0. Most of the structure consists of a union which is
22  * discriminated by `alg`.
23  *
24  * For multipart operations with driver delegation support, each multipart
25  * operation structure contains an `unsigned int id` field indicating which
26  * driver got assigned to do the operation. When the structure is not in use,
27  * 'id' is 0. The structure contains also a driver context which is the union
28  * of the contexts of all drivers able to handle the type of multipart
29  * operation.
30  *
31  * Note that when `alg` or `id` is 0, the content of other fields is undefined.
32  * In particular, it is not guaranteed that a freshly-initialized structure
33  * is all-zero: we initialize structures to something like `{0, 0}`, which
34  * is only guaranteed to initializes the first member of the union;
35  * GCC and Clang initialize the whole structure to 0 (at the time of writing),
36  * but MSVC and CompCert don't.
37  *
38  * In Mbed Crypto, multipart operation structures live independently from
39  * the key. This allows Mbed Crypto to free the key objects when destroying
40  * a key slot. If a multipart operation needs to remember the key after
41  * the setup function returns, the operation structure needs to contain a
42  * copy of the key.
43  */
44 /*
45  *  Copyright The Mbed TLS Contributors
46  *  SPDX-License-Identifier: Apache-2.0
47  *
48  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
49  *  not use this file except in compliance with the License.
50  *  You may obtain a copy of the License at
51  *
52  *  http://www.apache.org/licenses/LICENSE-2.0
53  *
54  *  Unless required by applicable law or agreed to in writing, software
55  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
56  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
57  *  See the License for the specific language governing permissions and
58  *  limitations under the License.
59  */
60 
61 #ifndef PSA_CRYPTO_STRUCT_H
62 #define PSA_CRYPTO_STRUCT_H
63 #include "mbedtls/private_access.h"
64 
65 #ifdef __cplusplus
66 extern "C" {
67 #endif
68 
69 /* Include the Mbed TLS configuration file, the way Mbed TLS does it
70  * in each of its header files. */
71 #include "mbedtls/build_info.h"
72 
73 #include "mbedtls/cmac.h"
74 #include "mbedtls/gcm.h"
75 #include "mbedtls/ccm.h"
76 #include "mbedtls/chachapoly.h"
77 
78 /* Include the context definition for the compiled-in drivers for the primitive
79  * algorithms. */
80 #include "psa/crypto_driver_contexts_primitives.h"
81 
82 struct psa_hash_operation_s
83 {
84     /** Unique ID indicating which driver got assigned to do the
85      * operation. Since driver contexts are driver-specific, swapping
86      * drivers halfway through the operation is not supported.
87      * ID values are auto-generated in psa_driver_wrappers.h.
88      * ID value zero means the context is not valid or not assigned to
89      * any driver (i.e. the driver context is not active, in use). */
90     unsigned int MBEDTLS_PRIVATE(id);
91     psa_driver_hash_context_t MBEDTLS_PRIVATE(ctx);
92 };
93 
94 #define PSA_HASH_OPERATION_INIT { 0, { 0 } }
psa_hash_operation_init(void)95 static inline struct psa_hash_operation_s psa_hash_operation_init( void )
96 {
97     const struct psa_hash_operation_s v = PSA_HASH_OPERATION_INIT;
98     return( v );
99 }
100 
101 struct psa_cipher_operation_s
102 {
103     /** Unique ID indicating which driver got assigned to do the
104      * operation. Since driver contexts are driver-specific, swapping
105      * drivers halfway through the operation is not supported.
106      * ID values are auto-generated in psa_crypto_driver_wrappers.h
107      * ID value zero means the context is not valid or not assigned to
108      * any driver (i.e. none of the driver contexts are active). */
109     unsigned int MBEDTLS_PRIVATE(id);
110 
111     unsigned int MBEDTLS_PRIVATE(iv_required) : 1;
112     unsigned int MBEDTLS_PRIVATE(iv_set) : 1;
113 
114     uint8_t MBEDTLS_PRIVATE(default_iv_length);
115 
116     psa_driver_cipher_context_t MBEDTLS_PRIVATE(ctx);
117 };
118 
119 #define PSA_CIPHER_OPERATION_INIT { 0, 0, 0, 0, { 0 } }
psa_cipher_operation_init(void)120 static inline struct psa_cipher_operation_s psa_cipher_operation_init( void )
121 {
122     const struct psa_cipher_operation_s v = PSA_CIPHER_OPERATION_INIT;
123     return( v );
124 }
125 
126 /* Include the context definition for the compiled-in drivers for the composite
127  * algorithms. */
128 #include "psa/crypto_driver_contexts_composites.h"
129 
130 struct psa_mac_operation_s
131 {
132     /** Unique ID indicating which driver got assigned to do the
133      * operation. Since driver contexts are driver-specific, swapping
134      * drivers halfway through the operation is not supported.
135      * ID values are auto-generated in psa_driver_wrappers.h
136      * ID value zero means the context is not valid or not assigned to
137      * any driver (i.e. none of the driver contexts are active). */
138     unsigned int MBEDTLS_PRIVATE(id);
139     uint8_t MBEDTLS_PRIVATE(mac_size);
140     unsigned int MBEDTLS_PRIVATE(is_sign) : 1;
141     psa_driver_mac_context_t MBEDTLS_PRIVATE(ctx);
142 };
143 
144 #define PSA_MAC_OPERATION_INIT { 0, 0, 0, { 0 } }
psa_mac_operation_init(void)145 static inline struct psa_mac_operation_s psa_mac_operation_init( void )
146 {
147     const struct psa_mac_operation_s v = PSA_MAC_OPERATION_INIT;
148     return( v );
149 }
150 
151 struct psa_aead_operation_s
152 {
153 
154     /** Unique ID indicating which driver got assigned to do the
155      * operation. Since driver contexts are driver-specific, swapping
156      * drivers halfway through the operation is not supported.
157      * ID values are auto-generated in psa_crypto_driver_wrappers.h
158      * ID value zero means the context is not valid or not assigned to
159      * any driver (i.e. none of the driver contexts are active). */
160     unsigned int MBEDTLS_PRIVATE(id);
161 
162     psa_algorithm_t MBEDTLS_PRIVATE(alg);
163     psa_key_type_t MBEDTLS_PRIVATE(key_type);
164 
165     size_t MBEDTLS_PRIVATE(ad_remaining);
166     size_t MBEDTLS_PRIVATE(body_remaining);
167 
168     unsigned int MBEDTLS_PRIVATE(nonce_set) : 1;
169     unsigned int MBEDTLS_PRIVATE(lengths_set) : 1;
170     unsigned int MBEDTLS_PRIVATE(ad_started) : 1;
171     unsigned int MBEDTLS_PRIVATE(body_started) : 1;
172     unsigned int MBEDTLS_PRIVATE(is_encrypt) : 1;
173 
174     psa_driver_aead_context_t MBEDTLS_PRIVATE(ctx);
175 };
176 
177 #define PSA_AEAD_OPERATION_INIT {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, {0}}
psa_aead_operation_init(void)178 static inline struct psa_aead_operation_s psa_aead_operation_init( void )
179 {
180     const struct psa_aead_operation_s v = PSA_AEAD_OPERATION_INIT;
181     return( v );
182 }
183 
184 #if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF)
185 typedef struct
186 {
187     uint8_t *MBEDTLS_PRIVATE(info);
188     size_t MBEDTLS_PRIVATE(info_length);
189 #if PSA_HASH_MAX_SIZE > 0xff
190 #error "PSA_HASH_MAX_SIZE does not fit in uint8_t"
191 #endif
192     uint8_t MBEDTLS_PRIVATE(offset_in_block);
193     uint8_t MBEDTLS_PRIVATE(block_number);
194     unsigned int MBEDTLS_PRIVATE(state) : 2;
195     unsigned int MBEDTLS_PRIVATE(info_set) : 1;
196     uint8_t MBEDTLS_PRIVATE(output_block)[PSA_HASH_MAX_SIZE];
197     uint8_t MBEDTLS_PRIVATE(prk)[PSA_HASH_MAX_SIZE];
198     struct psa_mac_operation_s MBEDTLS_PRIVATE(hmac);
199 } psa_hkdf_key_derivation_t;
200 #endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF */
201 
202 #if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) || \
203     defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
204 typedef enum
205 {
206     PSA_TLS12_PRF_STATE_INIT,       /* no input provided */
207     PSA_TLS12_PRF_STATE_SEED_SET,   /* seed has been set */
208     PSA_TLS12_PRF_STATE_KEY_SET,    /* key has been set */
209     PSA_TLS12_PRF_STATE_LABEL_SET,  /* label has been set */
210     PSA_TLS12_PRF_STATE_OUTPUT      /* output has been started */
211 } psa_tls12_prf_key_derivation_state_t;
212 
213 typedef struct psa_tls12_prf_key_derivation_s
214 {
215 #if PSA_HASH_MAX_SIZE > 0xff
216 #error "PSA_HASH_MAX_SIZE does not fit in uint8_t"
217 #endif
218 
219     /* Indicates how many bytes in the current HMAC block have
220      * not yet been read by the user. */
221     uint8_t MBEDTLS_PRIVATE(left_in_block);
222 
223     /* The 1-based number of the block. */
224     uint8_t MBEDTLS_PRIVATE(block_number);
225 
226     psa_tls12_prf_key_derivation_state_t MBEDTLS_PRIVATE(state);
227 
228     uint8_t *MBEDTLS_PRIVATE(secret);
229     size_t MBEDTLS_PRIVATE(secret_length);
230     uint8_t *MBEDTLS_PRIVATE(seed);
231     size_t MBEDTLS_PRIVATE(seed_length);
232     uint8_t *MBEDTLS_PRIVATE(label);
233     size_t MBEDTLS_PRIVATE(label_length);
234 
235     uint8_t MBEDTLS_PRIVATE(Ai)[PSA_HASH_MAX_SIZE];
236 
237     /* `HMAC_hash( prk, A( i ) + seed )` in the notation of RFC 5246, Sect. 5. */
238     uint8_t MBEDTLS_PRIVATE(output_block)[PSA_HASH_MAX_SIZE];
239 } psa_tls12_prf_key_derivation_t;
240 #endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) ||
241         * MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS */
242 
243 struct psa_key_derivation_s
244 {
245     psa_algorithm_t MBEDTLS_PRIVATE(alg);
246     unsigned int MBEDTLS_PRIVATE(can_output_key) : 1;
247     size_t MBEDTLS_PRIVATE(capacity);
248     union
249     {
250         /* Make the union non-empty even with no supported algorithms. */
251         uint8_t MBEDTLS_PRIVATE(dummy);
252 #if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF)
253         psa_hkdf_key_derivation_t MBEDTLS_PRIVATE(hkdf);
254 #endif
255 #if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) || \
256     defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
257         psa_tls12_prf_key_derivation_t MBEDTLS_PRIVATE(tls12_prf);
258 #endif
259     } MBEDTLS_PRIVATE(ctx);
260 };
261 
262 /* This only zeroes out the first byte in the union, the rest is unspecified. */
263 #define PSA_KEY_DERIVATION_OPERATION_INIT { 0, 0, 0, { 0 } }
psa_key_derivation_operation_init(void)264 static inline struct psa_key_derivation_s psa_key_derivation_operation_init(
265         void )
266 {
267     const struct psa_key_derivation_s v = PSA_KEY_DERIVATION_OPERATION_INIT;
268     return( v );
269 }
270 
271 struct psa_key_policy_s
272 {
273     psa_key_usage_t MBEDTLS_PRIVATE(usage);
274     psa_algorithm_t MBEDTLS_PRIVATE(alg);
275     psa_algorithm_t MBEDTLS_PRIVATE(alg2);
276 };
277 typedef struct psa_key_policy_s psa_key_policy_t;
278 
279 #define PSA_KEY_POLICY_INIT { 0, 0, 0 }
psa_key_policy_init(void)280 static inline struct psa_key_policy_s psa_key_policy_init( void )
281 {
282     const struct psa_key_policy_s v = PSA_KEY_POLICY_INIT;
283     return( v );
284 }
285 
286 /* The type used internally for key sizes.
287  * Public interfaces use size_t, but internally we use a smaller type. */
288 typedef uint16_t psa_key_bits_t;
289 /* The maximum value of the type used to represent bit-sizes.
290  * This is used to mark an invalid key size. */
291 #define PSA_KEY_BITS_TOO_LARGE          ( ( psa_key_bits_t ) -1 )
292 /* The maximum size of a key in bits.
293  * Currently defined as the maximum that can be represented, rounded down
294  * to a whole number of bytes.
295  * This is an uncast value so that it can be used in preprocessor
296  * conditionals. */
297 #define PSA_MAX_KEY_BITS 0xfff8
298 
299 /** A mask of flags that can be stored in key attributes.
300  *
301  * This type is also used internally to store flags in slots. Internal
302  * flags are defined in library/psa_crypto_core.h. Internal flags may have
303  * the same value as external flags if they are properly handled during
304  * key creation and in psa_get_key_attributes.
305  */
306 typedef uint16_t psa_key_attributes_flag_t;
307 
308 #define MBEDTLS_PSA_KA_FLAG_HAS_SLOT_NUMBER     \
309     ( (psa_key_attributes_flag_t) 0x0001 )
310 
311 /* A mask of key attribute flags used externally only.
312  * Only meant for internal checks inside the library. */
313 #define MBEDTLS_PSA_KA_MASK_EXTERNAL_ONLY (      \
314         MBEDTLS_PSA_KA_FLAG_HAS_SLOT_NUMBER |    \
315         0 )
316 
317 /* A mask of key attribute flags used both internally and externally.
318  * Currently there aren't any. */
319 #define MBEDTLS_PSA_KA_MASK_DUAL_USE (          \
320         0 )
321 
322 typedef struct
323 {
324     psa_key_type_t MBEDTLS_PRIVATE(type);
325     psa_key_bits_t MBEDTLS_PRIVATE(bits);
326     psa_key_lifetime_t MBEDTLS_PRIVATE(lifetime);
327     mbedtls_svc_key_id_t MBEDTLS_PRIVATE(id);
328     psa_key_policy_t MBEDTLS_PRIVATE(policy);
329     psa_key_attributes_flag_t MBEDTLS_PRIVATE(flags);
330 } psa_core_key_attributes_t;
331 
332 #define PSA_CORE_KEY_ATTRIBUTES_INIT { PSA_KEY_TYPE_NONE, 0,            \
333                                        PSA_KEY_LIFETIME_VOLATILE,       \
334                                        MBEDTLS_SVC_KEY_ID_INIT,         \
335                                        PSA_KEY_POLICY_INIT, 0 }
336 
337 struct psa_key_attributes_s
338 {
339     psa_core_key_attributes_t MBEDTLS_PRIVATE(core);
340 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
341     psa_key_slot_number_t MBEDTLS_PRIVATE(slot_number);
342 #endif /* MBEDTLS_PSA_CRYPTO_SE_C */
343     void *MBEDTLS_PRIVATE(domain_parameters);
344     size_t MBEDTLS_PRIVATE(domain_parameters_size);
345 };
346 
347 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
348 #define PSA_KEY_ATTRIBUTES_INIT { PSA_CORE_KEY_ATTRIBUTES_INIT, 0, NULL, 0 }
349 #else
350 #define PSA_KEY_ATTRIBUTES_INIT { PSA_CORE_KEY_ATTRIBUTES_INIT, NULL, 0 }
351 #endif
352 
psa_key_attributes_init(void)353 static inline struct psa_key_attributes_s psa_key_attributes_init( void )
354 {
355     const struct psa_key_attributes_s v = PSA_KEY_ATTRIBUTES_INIT;
356     return( v );
357 }
358 
psa_set_key_id(psa_key_attributes_t * attributes,mbedtls_svc_key_id_t key)359 static inline void psa_set_key_id( psa_key_attributes_t *attributes,
360                                    mbedtls_svc_key_id_t key )
361 {
362     psa_key_lifetime_t lifetime = attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(lifetime);
363 
364     attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(id) = key;
365 
366     if( PSA_KEY_LIFETIME_IS_VOLATILE( lifetime ) )
367     {
368         attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(lifetime) =
369             PSA_KEY_LIFETIME_FROM_PERSISTENCE_AND_LOCATION(
370                 PSA_KEY_LIFETIME_PERSISTENT,
371                 PSA_KEY_LIFETIME_GET_LOCATION( lifetime ) );
372     }
373 }
374 
psa_get_key_id(const psa_key_attributes_t * attributes)375 static inline mbedtls_svc_key_id_t psa_get_key_id(
376     const psa_key_attributes_t *attributes )
377 {
378     return( attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(id) );
379 }
380 
381 #ifdef MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER
mbedtls_set_key_owner_id(psa_key_attributes_t * attributes,mbedtls_key_owner_id_t owner)382 static inline void mbedtls_set_key_owner_id( psa_key_attributes_t *attributes,
383                                              mbedtls_key_owner_id_t owner )
384 {
385     attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(id).MBEDTLS_PRIVATE(owner) = owner;
386 }
387 #endif
388 
psa_set_key_lifetime(psa_key_attributes_t * attributes,psa_key_lifetime_t lifetime)389 static inline void psa_set_key_lifetime( psa_key_attributes_t *attributes,
390                                         psa_key_lifetime_t lifetime )
391 {
392     attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(lifetime) = lifetime;
393     if( PSA_KEY_LIFETIME_IS_VOLATILE( lifetime ) )
394     {
395 #ifdef MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER
396         attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(id).MBEDTLS_PRIVATE(key_id) = 0;
397 #else
398         attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(id) = 0;
399 #endif
400     }
401 }
402 
psa_get_key_lifetime(const psa_key_attributes_t * attributes)403 static inline psa_key_lifetime_t psa_get_key_lifetime(
404     const psa_key_attributes_t *attributes )
405 {
406     return( attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(lifetime) );
407 }
408 
psa_extend_key_usage_flags(psa_key_usage_t * usage_flags)409 static inline void psa_extend_key_usage_flags( psa_key_usage_t *usage_flags )
410 {
411     if( *usage_flags & PSA_KEY_USAGE_SIGN_HASH )
412         *usage_flags |= PSA_KEY_USAGE_SIGN_MESSAGE;
413 
414     if( *usage_flags & PSA_KEY_USAGE_VERIFY_HASH )
415         *usage_flags |= PSA_KEY_USAGE_VERIFY_MESSAGE;
416 }
417 
psa_set_key_usage_flags(psa_key_attributes_t * attributes,psa_key_usage_t usage_flags)418 static inline void psa_set_key_usage_flags(psa_key_attributes_t *attributes,
419                                            psa_key_usage_t usage_flags)
420 {
421     psa_extend_key_usage_flags( &usage_flags );
422     attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(policy).MBEDTLS_PRIVATE(usage) = usage_flags;
423 }
424 
psa_get_key_usage_flags(const psa_key_attributes_t * attributes)425 static inline psa_key_usage_t psa_get_key_usage_flags(
426     const psa_key_attributes_t *attributes )
427 {
428     return( attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(policy).MBEDTLS_PRIVATE(usage) );
429 }
430 
psa_set_key_algorithm(psa_key_attributes_t * attributes,psa_algorithm_t alg)431 static inline void psa_set_key_algorithm( psa_key_attributes_t *attributes,
432                                          psa_algorithm_t alg )
433 {
434     attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(policy).MBEDTLS_PRIVATE(alg) = alg;
435 }
436 
psa_get_key_algorithm(const psa_key_attributes_t * attributes)437 static inline psa_algorithm_t psa_get_key_algorithm(
438     const psa_key_attributes_t *attributes )
439 {
440     return( attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(policy).MBEDTLS_PRIVATE(alg) );
441 }
442 
443 /* This function is declared in crypto_extra.h, which comes after this
444  * header file, but we need the function here, so repeat the declaration. */
445 psa_status_t psa_set_key_domain_parameters( psa_key_attributes_t *attributes,
446                                            psa_key_type_t type,
447                                            const uint8_t *data,
448                                            size_t data_length );
449 
psa_set_key_type(psa_key_attributes_t * attributes,psa_key_type_t type)450 static inline void psa_set_key_type( psa_key_attributes_t *attributes,
451                                     psa_key_type_t type )
452 {
453     if( attributes->MBEDTLS_PRIVATE(domain_parameters) == NULL )
454     {
455         /* Common case: quick path */
456         attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(type) = type;
457     }
458     else
459     {
460         /* Call the bigger function to free the old domain paramteres.
461          * Ignore any errors which may arise due to type requiring
462          * non-default domain parameters, since this function can't
463          * report errors. */
464         (void) psa_set_key_domain_parameters( attributes, type, NULL, 0 );
465     }
466 }
467 
psa_get_key_type(const psa_key_attributes_t * attributes)468 static inline psa_key_type_t psa_get_key_type(
469     const psa_key_attributes_t *attributes )
470 {
471     return( attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(type) );
472 }
473 
psa_set_key_bits(psa_key_attributes_t * attributes,size_t bits)474 static inline void psa_set_key_bits( psa_key_attributes_t *attributes,
475                                     size_t bits )
476 {
477     if( bits > PSA_MAX_KEY_BITS )
478         attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(bits) = PSA_KEY_BITS_TOO_LARGE;
479     else
480         attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(bits) = (psa_key_bits_t) bits;
481 }
482 
psa_get_key_bits(const psa_key_attributes_t * attributes)483 static inline size_t psa_get_key_bits(
484     const psa_key_attributes_t *attributes )
485 {
486     return( attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(bits) );
487 }
488 
489 #ifdef __cplusplus
490 }
491 #endif
492 
493 #endif /* PSA_CRYPTO_STRUCT_H */
494