1 /*
2  *  PSA AEAD driver entry points
3  */
4 /*
5  *  Copyright The Mbed TLS Contributors
6  *  SPDX-License-Identifier: Apache-2.0
7  *
8  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
9  *  not use this file except in compliance with the License.
10  *  You may obtain a copy of the License at
11  *
12  *  http://www.apache.org/licenses/LICENSE-2.0
13  *
14  *  Unless required by applicable law or agreed to in writing, software
15  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
16  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17  *  See the License for the specific language governing permissions and
18  *  limitations under the License.
19  */
20 
21 #ifndef PSA_CRYPTO_AEAD_H
22 #define PSA_CRYPTO_AEAD_H
23 
24 #include <psa/crypto.h>
25 
26 /**
27  * \brief Process an authenticated encryption operation.
28  *
29  * \note The signature of this function is that of a PSA driver
30  *       aead_encrypt entry point. This function behaves as an aead_encrypt
31  *       entry point as defined in the PSA driver interface specification for
32  *       transparent drivers.
33  *
34  * \param[in]  attributes         The attributes of the key to use for the
35  *                                operation.
36  * \param[in]  key_buffer         The buffer containing the key context.
37  * \param      key_buffer_size    Size of the \p key_buffer buffer in bytes.
38  * \param      alg                The AEAD algorithm to compute.
39  * \param[in]  nonce              Nonce or IV to use.
40  * \param      nonce_length       Size of the nonce buffer in bytes. This must
41  *                                be appropriate for the selected algorithm.
42  *                                The default nonce size is
43  *                                PSA_AEAD_NONCE_LENGTH(key_type, alg) where
44  *                                key_type is the type of key.
45  * \param[in]  additional_data    Additional data that will be authenticated
46  *                                but not encrypted.
47  * \param      additional_data_length  Size of additional_data in bytes.
48  * \param[in]  plaintext          Data that will be authenticated and encrypted.
49  * \param      plaintext_length   Size of plaintext in bytes.
50  * \param[out] ciphertext         Output buffer for the authenticated and
51  *                                encrypted data. The additional data is not
52  *                                part of this output. For algorithms where the
53  *                                encrypted data and the authentication tag are
54  *                                defined as separate outputs, the
55  *                                authentication tag is appended to the
56  *                                encrypted data.
57  * \param      ciphertext_size    Size of the ciphertext buffer in bytes. This
58  *                                must be appropriate for the selected algorithm
59  *                                and key:
60  *                                - A sufficient output size is
61  *                                  PSA_AEAD_ENCRYPT_OUTPUT_SIZE(key_type, alg,
62  *                                  plaintext_length) where key_type is the type
63  *                                  of key.
64  *                                - PSA_AEAD_ENCRYPT_OUTPUT_MAX_SIZE(
65  *                                  plaintext_length) evaluates to the maximum
66  *                                  ciphertext size of any supported AEAD
67  *                                  encryption.
68  * \param[out] ciphertext_length  On success, the size of the output in the
69  *                                ciphertext buffer.
70  *
71  * \retval #PSA_SUCCESS Success.
72  * \retval #PSA_ERROR_NOT_SUPPORTED
73  *         \p alg is not supported.
74  * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
75  * \retval #PSA_ERROR_BUFFER_TOO_SMALL
76  *         ciphertext_size is too small.
77  * \retval #PSA_ERROR_CORRUPTION_DETECTED
78  */
79 psa_status_t mbedtls_psa_aead_encrypt(
80     const psa_key_attributes_t *attributes,
81     const uint8_t *key_buffer, size_t key_buffer_size,
82     psa_algorithm_t alg,
83     const uint8_t *nonce, size_t nonce_length,
84     const uint8_t *additional_data, size_t additional_data_length,
85     const uint8_t *plaintext, size_t plaintext_length,
86     uint8_t *ciphertext, size_t ciphertext_size, size_t *ciphertext_length );
87 
88 /**
89  * \brief Process an authenticated decryption operation.
90  *
91  * \note The signature of this function is that of a PSA driver
92  *       aead_decrypt entry point. This function behaves as an aead_decrypt
93  *       entry point as defined in the PSA driver interface specification for
94  *       transparent drivers.
95  *
96  * \param[in]  attributes         The attributes of the key to use for the
97  *                                operation.
98  * \param[in]  key_buffer         The buffer containing the key context.
99  * \param      key_buffer_size    Size of the \p key_buffer buffer in bytes.
100  * \param      alg                The AEAD algorithm to compute.
101  * \param[in]  nonce              Nonce or IV to use.
102  * \param      nonce_length       Size of the nonce buffer in bytes. This must
103  *                                be appropriate for the selected algorithm.
104  *                                The default nonce size is
105  *                                PSA_AEAD_NONCE_LENGTH(key_type, alg) where
106  *                                key_type is the type of key.
107  * \param[in]  additional_data    Additional data that has been authenticated
108  *                                but not encrypted.
109  * \param      additional_data_length  Size of additional_data in bytes.
110  * \param[in]  ciphertext         Data that has been authenticated and
111  *                                encrypted. For algorithms where the encrypted
112  *                                data and the authentication tag are defined
113  *                                as separate inputs, the buffer contains
114  *                                encrypted data followed by the authentication
115  *                                tag.
116  * \param      ciphertext_length  Size of ciphertext in bytes.
117  * \param[out] plaintext          Output buffer for the decrypted data.
118  * \param      plaintext_size     Size of the plaintext buffer in bytes. This
119  *                                must be appropriate for the selected algorithm
120  *                                and key:
121  *                                - A sufficient output size is
122  *                                  PSA_AEAD_DECRYPT_OUTPUT_SIZE(key_type, alg,
123  *                                  ciphertext_length) where key_type is the
124  *                                  type of key.
125  *                                - PSA_AEAD_DECRYPT_OUTPUT_MAX_SIZE(
126  *                                  ciphertext_length) evaluates to the maximum
127  *                                  plaintext size of any supported AEAD
128  *                                  decryption.
129  * \param[out] plaintext_length   On success, the size of the output in the
130  *                                plaintext buffer.
131  *
132  * \retval #PSA_SUCCESS Success.
133  * \retval #PSA_ERROR_INVALID_SIGNATURE
134  *         The cipher is not authentic.
135  * \retval #PSA_ERROR_NOT_SUPPORTED
136  *         \p alg is not supported.
137  * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
138  * \retval #PSA_ERROR_BUFFER_TOO_SMALL
139  *         plaintext_size is too small.
140  * \retval #PSA_ERROR_CORRUPTION_DETECTED
141  */
142 psa_status_t mbedtls_psa_aead_decrypt(
143     const psa_key_attributes_t *attributes,
144     const uint8_t *key_buffer, size_t key_buffer_size,
145     psa_algorithm_t alg,
146     const uint8_t *nonce, size_t nonce_length,
147     const uint8_t *additional_data, size_t additional_data_length,
148     const uint8_t *ciphertext, size_t ciphertext_length,
149     uint8_t *plaintext, size_t plaintext_size, size_t *plaintext_length );
150 
151 /** Set the key for a multipart authenticated encryption operation.
152  *
153  *  \note The signature of this function is that of a PSA driver
154  *       aead_encrypt_setup entry point. This function behaves as an
155  *       aead_encrypt_setup entry point as defined in the PSA driver interface
156  *       specification for transparent drivers.
157  *
158  * If an error occurs at any step after a call to
159  * mbedtls_psa_aead_encrypt_setup(), the operation is reset by the PSA core by a
160  * call to mbedtls_psa_aead_abort(). The PSA core may call
161  * mbedtls_psa_aead_abort() at any time after the operation has been
162  * initialized, and is required to when the operation is no longer needed.
163  *
164  * \param[in,out] operation     The operation object to set up. It must have
165  *                              been initialized as per the documentation for
166  *                              #mbedtls_psa_aead_operation_t and not yet in
167  *                              use.
168  * \param[in]  attributes       The attributes of the key to use for the
169  *                              operation.
170  * \param[in]  key_buffer       The buffer containing the key context.
171  * \param      key_buffer_size  Size of the \p key_buffer buffer in bytes.
172                                 It must be consistent with the size in bits
173                                 recorded in \p attributes.
174  * \param alg                   The AEAD algorithm to compute
175  *                              (\c PSA_ALG_XXX value such that
176  *                              #PSA_ALG_IS_AEAD(\p alg) is true).
177  *
178  * \retval #PSA_SUCCESS
179  *         Success.
180  * \retval #PSA_ERROR_INVALID_ARGUMENT
181  *         An invalid block length was supplied.
182  * \retval #PSA_ERROR_NOT_SUPPORTED
183  *         \p alg is not supported.
184  * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
185  *         Failed to allocate memory for key material
186  */
187 psa_status_t mbedtls_psa_aead_encrypt_setup(
188     mbedtls_psa_aead_operation_t *operation,
189     const psa_key_attributes_t *attributes,
190     const uint8_t *key_buffer,
191     size_t key_buffer_size,
192     psa_algorithm_t alg );
193 
194 /** Set the key for a multipart authenticated decryption operation.
195  *
196  * \note The signature of this function is that of a PSA driver
197  *       aead_decrypt_setup entry point. This function behaves as an
198  *       aead_decrypt_setup entry point as defined in the PSA driver interface
199  *       specification for transparent drivers.
200  *
201  * If an error occurs at any step after a call to
202  * mbedtls_psa_aead_decrypt_setup(), the PSA core resets the operation by a
203  * call to mbedtls_psa_aead_abort(). The PSA core may call
204  * mbedtls_psa_aead_abort() at any time after the operation has been
205  * initialized, and is required to when the operation is no longer needed.
206  *
207  * \param[in,out] operation     The operation object to set up. It must have
208  *                              been initialized as per the documentation for
209  *                              #mbedtls_psa_aead_operation_t and not yet in
210  *                              use.
211  * \param[in]  attributes       The attributes of the key to use for the
212  *                              operation.
213  * \param[in]  key_buffer       The buffer containing the key context.
214  * \param      key_buffer_size  Size of the \p key_buffer buffer in bytes.
215                                 It must be consistent with the size in bits
216                                 recorded in \p attributes.
217  * \param alg                   The AEAD algorithm to compute
218  *                              (\c PSA_ALG_XXX value such that
219  *                              #PSA_ALG_IS_AEAD(\p alg) is true).
220  *
221  * \retval #PSA_SUCCESS
222  *         Success.
223  * \retval #PSA_ERROR_INVALID_ARGUMENT
224  *         An invalid block length was supplied.
225  * \retval #PSA_ERROR_NOT_SUPPORTED
226  *         \p alg is not supported.
227  * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
228  *         Failed to allocate memory for key material
229  */
230 psa_status_t mbedtls_psa_aead_decrypt_setup(
231     mbedtls_psa_aead_operation_t *operation,
232     const psa_key_attributes_t *attributes,
233     const uint8_t *key_buffer,
234     size_t key_buffer_size,
235     psa_algorithm_t alg );
236 
237 /** Set the nonce for an authenticated encryption or decryption operation.
238  *
239  * \note The signature of this function is that of a PSA driver aead_set_nonce
240  *       entry point. This function behaves as an aead_set_nonce entry point as
241  *       defined in the PSA driver interface specification for transparent
242  *       drivers.
243  *
244  * This function sets the nonce for the authenticated
245  * encryption or decryption operation.
246  *
247  * The PSA core calls mbedtls_psa_aead_encrypt_setup() or
248  * mbedtls_psa_aead_decrypt_setup() before calling this function.
249  *
250  * If this function returns an error status, the PSA core will call
251  * mbedtls_psa_aead_abort().
252  *
253  * \param[in,out] operation     Active AEAD operation.
254  * \param[in] nonce             Buffer containing the nonce to use.
255  * \param nonce_length          Size of the nonce in bytes.
256  *
257  * \retval #PSA_SUCCESS
258  *         Success.
259  * \retval #PSA_ERROR_INVALID_ARGUMENT
260  *         The size of \p nonce is not acceptable for the chosen algorithm.
261  * \retval #PSA_ERROR_NOT_SUPPORTED
262  *         Algorithm previously set is not supported in this configuration of
263  *         the library.
264  */
265 psa_status_t mbedtls_psa_aead_set_nonce(
266     mbedtls_psa_aead_operation_t *operation,
267     const uint8_t *nonce,
268     size_t nonce_length );
269 
270 /** Declare the lengths of the message and additional data for AEAD.
271  *
272  * \note The signature of this function is that of a PSA driver aead_set_lengths
273  *       entry point. This function behaves as an aead_set_lengths entry point
274  *       as defined in the PSA driver interface specification for transparent
275  *       drivers.
276  *
277  * The PSA core calls this function before calling mbedtls_psa_aead_update_ad()
278  * or mbedtls_psa_aead_update() if the algorithm for the operation requires it.
279  * If the algorithm does not require it, calling this function is optional, but
280  * if this function is called then the implementation must enforce the lengths.
281  *
282  * The PSA core may call this function before or after setting the nonce with
283  * mbedtls_psa_aead_set_nonce().
284  *
285  * - For #PSA_ALG_CCM, calling this function is required.
286  * - For the other AEAD algorithms defined in this specification, calling
287  *   this function is not required.
288  *
289  * If this function returns an error status, the PSA core calls
290  * mbedtls_psa_aead_abort().
291  *
292  * \param[in,out] operation     Active AEAD operation.
293  * \param ad_length             Size of the non-encrypted additional
294  *                              authenticated data in bytes.
295  * \param plaintext_length      Size of the plaintext to encrypt in bytes.
296  *
297  * \retval #PSA_SUCCESS
298  *         Success.
299  * \retval #PSA_ERROR_INVALID_ARGUMENT
300  *         At least one of the lengths is not acceptable for the chosen
301  *         algorithm.
302  * \retval #PSA_ERROR_NOT_SUPPORTED
303  *         Algorithm previously set is not supported in this configuration of
304  *         the library.
305  */
306 psa_status_t mbedtls_psa_aead_set_lengths(
307     mbedtls_psa_aead_operation_t *operation,
308     size_t ad_length,
309     size_t plaintext_length );
310 
311 /** Pass additional data to an active AEAD operation.
312  *
313  *  \note The signature of this function is that of a PSA driver
314  *       aead_update_ad entry point. This function behaves as an aead_update_ad
315  *       entry point as defined in the PSA driver interface specification for
316  *       transparent drivers.
317  *
318  * Additional data is authenticated, but not encrypted.
319  *
320  * The PSA core can call this function multiple times to pass successive
321  * fragments of the additional data. It will not call this function after
322  * passing data to encrypt or decrypt with mbedtls_psa_aead_update().
323  *
324  * Before calling this function, the PSA core will:
325  *    1. Call either mbedtls_psa_aead_encrypt_setup() or
326  *       mbedtls_psa_aead_decrypt_setup().
327  *    2. Set the nonce with mbedtls_psa_aead_set_nonce().
328  *
329  * If this function returns an error status, the PSA core will call
330  * mbedtls_psa_aead_abort().
331  *
332  * \param[in,out] operation     Active AEAD operation.
333  * \param[in] input             Buffer containing the fragment of
334  *                              additional data.
335  * \param input_length          Size of the \p input buffer in bytes.
336  *
337  * \retval #PSA_SUCCESS
338  *         Success.
339  * \retval #PSA_ERROR_NOT_SUPPORTED
340  *         Algorithm previously set is not supported in this configuration of
341  *         the library.
342  */
343 psa_status_t mbedtls_psa_aead_update_ad(
344     mbedtls_psa_aead_operation_t *operation,
345     const uint8_t *input,
346     size_t input_length );
347 
348 /** Encrypt or decrypt a message fragment in an active AEAD operation.
349  *
350  *  \note The signature of this function is that of a PSA driver
351  *       aead_update entry point. This function behaves as an aead_update entry
352  *       point as defined in the PSA driver interface specification for
353  *       transparent drivers.
354  *
355  * Before calling this function, the PSA core will:
356  *    1. Call either mbedtls_psa_aead_encrypt_setup() or
357  *       mbedtls_psa_aead_decrypt_setup(). The choice of setup function
358  *       determines whether this function encrypts or decrypts its input.
359  *    2. Set the nonce with mbedtls_psa_aead_set_nonce().
360  *    3. Call mbedtls_psa_aead_update_ad() to pass all the additional data.
361  *
362  * If this function returns an error status, the PSA core will call
363  * mbedtls_psa_aead_abort().
364  *
365  * This function does not require the input to be aligned to any
366  * particular block boundary. If the implementation can only process
367  * a whole block at a time, it must consume all the input provided, but
368  * it may delay the end of the corresponding output until a subsequent
369  * call to mbedtls_psa_aead_update(), mbedtls_psa_aead_finish() provides
370  * sufficient input. The amount of data that can be delayed in this way is
371  * bounded by #PSA_AEAD_UPDATE_OUTPUT_SIZE.
372  *
373  * \param[in,out] operation     Active AEAD operation.
374  * \param[in] input             Buffer containing the message fragment to
375  *                              encrypt or decrypt.
376  * \param input_length          Size of the \p input buffer in bytes.
377  * \param[out] output           Buffer where the output is to be written.
378  * \param output_size           Size of the \p output buffer in bytes.
379  *                              This must be appropriate for the selected
380  *                                algorithm and key:
381  *                                - A sufficient output size is
382  *                                  #PSA_AEAD_UPDATE_OUTPUT_SIZE(\c key_type,
383  *                                  \c alg, \p input_length) where
384  *                                  \c key_type is the type of key and \c alg is
385  *                                  the algorithm that were used to set up the
386  *                                  operation.
387  *                                - #PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(\p
388  *                                  input_length) evaluates to the maximum
389  *                                  output size of any supported AEAD
390  *                                  algorithm.
391  * \param[out] output_length    On success, the number of bytes
392  *                              that make up the returned output.
393  *
394  * \retval #PSA_SUCCESS
395  *         Success.
396  *
397  * \retval #PSA_ERROR_BUFFER_TOO_SMALL
398  *         The size of the \p output buffer is too small.
399  *         #PSA_AEAD_UPDATE_OUTPUT_SIZE(\c key_type, \c alg, \p input_length) or
400  *         #PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(\p input_length) can be used to
401  *         determine the required buffer size.
402  */
403 psa_status_t mbedtls_psa_aead_update(
404     mbedtls_psa_aead_operation_t *operation,
405     const uint8_t *input,
406     size_t input_length,
407     uint8_t *output,
408     size_t output_size,
409     size_t *output_length );
410 
411 /** Finish encrypting a message in an AEAD operation.
412  *
413  *  \note The signature of this function is that of a PSA driver
414  *       aead_finish entry point. This function behaves as an aead_finish entry
415  *       point as defined in the PSA driver interface specification for
416  *       transparent drivers.
417  *
418  * The operation must have been set up by the PSA core with
419  * mbedtls_psa_aead_encrypt_setup().
420  *
421  * This function finishes the authentication of the additional data
422  * formed by concatenating the inputs passed to preceding calls to
423  * mbedtls_psa_aead_update_ad() with the plaintext formed by concatenating the
424  * inputs passed to preceding calls to mbedtls_psa_aead_update().
425  *
426  * This function has two output buffers:
427  * - \p ciphertext contains trailing ciphertext that was buffered from
428  *   preceding calls to mbedtls_psa_aead_update().
429  * - \p tag contains the authentication tag.
430  *
431  * Whether or not this function returns successfuly, the PSA core subsequently
432  * calls mbedtls_psa_aead_abort() to deactivate the operation.
433  *
434  * \param[in,out] operation     Active AEAD operation.
435  * \param[out] ciphertext       Buffer where the last part of the ciphertext
436  *                              is to be written.
437  * \param ciphertext_size       Size of the \p ciphertext buffer in bytes.
438  *                              This must be appropriate for the selected
439  *                              algorithm and key:
440  *                              - A sufficient output size is
441  *                                #PSA_AEAD_FINISH_OUTPUT_SIZE(\c key_type,
442  *                                \c alg) where \c key_type is the type of key
443  *                                and \c alg is the algorithm that were used to
444  *                                set up the operation.
445  *                              - #PSA_AEAD_FINISH_OUTPUT_MAX_SIZE evaluates to
446  *                                the maximum output size of any supported AEAD
447  *                                algorithm.
448  * \param[out] ciphertext_length On success, the number of bytes of
449  *                              returned ciphertext.
450  * \param[out] tag              Buffer where the authentication tag is
451  *                              to be written.
452  * \param tag_size              Size of the \p tag buffer in bytes.
453  *                              This must be appropriate for the selected
454  *                              algorithm and key:
455  *                              - The exact tag size is #PSA_AEAD_TAG_LENGTH(\c
456  *                                key_type, \c key_bits, \c alg) where
457  *                                \c key_type and \c key_bits are the type and
458  *                                bit-size of the key, and \c alg are the
459  *                                algorithm that were used in the call to
460  *                                mbedtls_psa_aead_encrypt_setup().
461  *                              - #PSA_AEAD_TAG_MAX_SIZE evaluates to the
462  *                                maximum tag size of any supported AEAD
463  *                                algorithm.
464  * \param[out] tag_length       On success, the number of bytes
465  *                              that make up the returned tag.
466  *
467  * \retval #PSA_SUCCESS
468  *         Success.
469  * \retval #PSA_ERROR_BUFFER_TOO_SMALL
470  *         The size of the \p tag buffer is too small.
471  *         #PSA_AEAD_TAG_LENGTH(\c key_type, key_bits, \c alg) or
472  *         #PSA_AEAD_TAG_MAX_SIZE can be used to determine the required \p tag
473  *         buffer size.
474  */
475 psa_status_t mbedtls_psa_aead_finish(
476     mbedtls_psa_aead_operation_t *operation,
477     uint8_t *ciphertext,
478     size_t ciphertext_size,
479     size_t *ciphertext_length,
480     uint8_t *tag,
481     size_t tag_size,
482     size_t *tag_length );
483 
484 /** Abort an AEAD operation.
485  *
486  *  \note The signature of this function is that of a PSA driver
487  *       aead_abort entry point. This function behaves as an aead_abort entry
488  *       point as defined in the PSA driver interface specification for
489  *       transparent drivers.
490  *
491  * Aborting an operation frees all associated resources except for the
492  * \p operation structure itself. Once aborted, the operation object
493  * can be reused for another operation by the PSA core by it calling
494  * mbedtls_psa_aead_encrypt_setup() or mbedtls_psa_aead_decrypt_setup() again.
495  *
496  * The PSA core may call this function any time after the operation object has
497  * been initialized as described in #mbedtls_psa_aead_operation_t.
498  *
499  * In particular, calling mbedtls_psa_aead_abort() after the operation has been
500  * terminated by a call to mbedtls_psa_aead_abort() or
501  * mbedtls_psa_aead_finish() is safe and has no effect.
502  *
503  * \param[in,out] operation     Initialized AEAD operation.
504  *
505  * \retval #PSA_SUCCESS
506  *         Success.
507  */
508 psa_status_t mbedtls_psa_aead_abort(
509     mbedtls_psa_aead_operation_t *operation );
510 
511 #endif /* PSA_CRYPTO_AEAD */
512