4 * \brief Public Key abstraction layer
7 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
8 * SPDX-License-Identifier: Apache-2.0
10 * Licensed under the Apache License, Version 2.0 (the "License"); you may
11 * not use this file except in compliance with the License.
12 * You may obtain a copy of the License at
14 * http://www.apache.org/licenses/LICENSE-2.0
16 * Unless required by applicable law or agreed to in writing, software
17 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
18 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
19 * See the License for the specific language governing permissions and
20 * limitations under the License.
22 * This file is part of mbed TLS (https://tls.mbed.org)
28 #if !defined(MBEDTLS_CONFIG_FILE)
31 #include MBEDTLS_CONFIG_FILE
36 #if defined(MBEDTLS_RSA_C)
40 #if defined(MBEDTLS_ECP_C)
44 #if defined(MBEDTLS_ECDSA_C)
48 #if defined(MBEDTLS_USE_PSA_CRYPTO)
49 #include "psa/crypto.h"
52 #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
53 !defined(inline) && !defined(__cplusplus)
54 #define inline __inline
57 #define MBEDTLS_ERR_PK_ALLOC_FAILED -0x3F80 /**< Memory allocation failed. */
58 #define MBEDTLS_ERR_PK_TYPE_MISMATCH -0x3F00 /**< Type mismatch, eg attempt to encrypt with an ECDSA key */
59 #define MBEDTLS_ERR_PK_BAD_INPUT_DATA -0x3E80 /**< Bad input parameters to function. */
60 #define MBEDTLS_ERR_PK_FILE_IO_ERROR -0x3E00 /**< Read/write of file failed. */
61 #define MBEDTLS_ERR_PK_KEY_INVALID_VERSION -0x3D80 /**< Unsupported key version */
62 #define MBEDTLS_ERR_PK_KEY_INVALID_FORMAT -0x3D00 /**< Invalid key tag or value. */
63 #define MBEDTLS_ERR_PK_UNKNOWN_PK_ALG -0x3C80 /**< Key algorithm is unsupported (only RSA and EC are supported). */
64 #define MBEDTLS_ERR_PK_PASSWORD_REQUIRED -0x3C00 /**< Private key password can't be empty. */
65 #define MBEDTLS_ERR_PK_PASSWORD_MISMATCH -0x3B80 /**< Given private key password does not allow for correct decryption. */
66 #define MBEDTLS_ERR_PK_INVALID_PUBKEY -0x3B00 /**< The pubkey tag or value is invalid (only RSA and EC are supported). */
67 #define MBEDTLS_ERR_PK_INVALID_ALG -0x3A80 /**< The algorithm tag or value is invalid. */
68 #define MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE -0x3A00 /**< Elliptic curve is unsupported (only NIST curves are supported). */
69 #define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE -0x3980 /**< Unavailable feature, e.g. RSA disabled for RSA key. */
70 #define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH -0x3900 /**< The buffer contains a valid signature followed by more data. */
72 /* MBEDTLS_ERR_PK_HW_ACCEL_FAILED is deprecated and should not be used. */
73 #define MBEDTLS_ERR_PK_HW_ACCEL_FAILED -0x3880 /**< PK hardware accelerator failed. */
80 * \brief Public key types
89 MBEDTLS_PK_RSASSA_PSS,
94 * \brief Options for RSASSA-PSS signature verification.
95 * See \c mbedtls_rsa_rsassa_pss_verify_ext()
97 typedef struct mbedtls_pk_rsassa_pss_options
99 mbedtls_md_type_t mgf1_hash_id;
100 int expected_salt_len;
102 } mbedtls_pk_rsassa_pss_options;
105 * \brief Types for interfacing with the debug module
109 MBEDTLS_PK_DEBUG_NONE = 0,
110 MBEDTLS_PK_DEBUG_MPI,
111 MBEDTLS_PK_DEBUG_ECP,
112 } mbedtls_pk_debug_type;
115 * \brief Item to send to the debug module
117 typedef struct mbedtls_pk_debug_item
119 mbedtls_pk_debug_type type;
122 } mbedtls_pk_debug_item;
124 /** Maximum number of item send for debugging, plus 1 */
125 #define MBEDTLS_PK_DEBUG_MAX_ITEMS 3
128 * \brief Public key information and operations
130 typedef struct mbedtls_pk_info_t mbedtls_pk_info_t;
133 * \brief Public key container
135 typedef struct mbedtls_pk_context
137 const mbedtls_pk_info_t * pk_info; /**< Public key information */
138 void * pk_ctx; /**< Underlying public key context */
139 } mbedtls_pk_context;
141 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
143 * \brief Context for resuming operations
147 const mbedtls_pk_info_t * pk_info; /**< Public key information */
148 void * rs_ctx; /**< Underlying restart context */
149 } mbedtls_pk_restart_ctx;
150 #else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
151 /* Now we can declare functions that take a pointer to that */
152 typedef void mbedtls_pk_restart_ctx;
153 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
155 #if defined(MBEDTLS_RSA_C)
157 * Quick access to an RSA context inside a PK context.
159 * \warning You must make sure the PK context actually holds an RSA context
160 * before using this function!
162 static inline mbedtls_rsa_context *mbedtls_pk_rsa( const mbedtls_pk_context pk )
164 return( (mbedtls_rsa_context *) (pk).pk_ctx );
166 #endif /* MBEDTLS_RSA_C */
168 #if defined(MBEDTLS_ECP_C)
170 * Quick access to an EC context inside a PK context.
172 * \warning You must make sure the PK context actually holds an EC context
173 * before using this function!
175 static inline mbedtls_ecp_keypair *mbedtls_pk_ec( const mbedtls_pk_context pk )
177 return( (mbedtls_ecp_keypair *) (pk).pk_ctx );
179 #endif /* MBEDTLS_ECP_C */
181 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
183 * \brief Types for RSA-alt abstraction
185 typedef int (*mbedtls_pk_rsa_alt_decrypt_func)( void *ctx, int mode, size_t *olen,
186 const unsigned char *input, unsigned char *output,
187 size_t output_max_len );
188 typedef int (*mbedtls_pk_rsa_alt_sign_func)( void *ctx,
189 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
190 int mode, mbedtls_md_type_t md_alg, unsigned int hashlen,
191 const unsigned char *hash, unsigned char *sig );
192 typedef size_t (*mbedtls_pk_rsa_alt_key_len_func)( void *ctx );
193 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
196 * \brief Return information associated with the given PK type
198 * \param pk_type PK type to search for.
200 * \return The PK info associated with the type or NULL if not found.
202 const mbedtls_pk_info_t *mbedtls_pk_info_from_type( mbedtls_pk_type_t pk_type );
205 * \brief Initialize a #mbedtls_pk_context (as NONE).
207 * \param ctx The context to initialize.
208 * This must not be \c NULL.
210 void mbedtls_pk_init( mbedtls_pk_context *ctx );
213 * \brief Free the components of a #mbedtls_pk_context.
215 * \param ctx The context to clear. It must have been initialized.
216 * If this is \c NULL, this function does nothing.
218 * \note For contexts that have been set up with
219 * mbedtls_pk_setup_opaque(), this does not free the underlying
220 * key slot and you still need to call psa_destroy_key()
221 * independently if you want to destroy that key.
223 void mbedtls_pk_free( mbedtls_pk_context *ctx );
225 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
227 * \brief Initialize a restart context
229 * \param ctx The context to initialize.
230 * This must not be \c NULL.
232 void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx );
235 * \brief Free the components of a restart context
237 * \param ctx The context to clear. It must have been initialized.
238 * If this is \c NULL, this function does nothing.
240 void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx );
241 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
244 * \brief Initialize a PK context with the information given
245 * and allocates the type-specific PK subcontext.
247 * \param ctx Context to initialize. It must not have been set
248 * up yet (type #MBEDTLS_PK_NONE).
249 * \param info Information to use
251 * \return 0 on success,
252 * MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input,
253 * MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
255 * \note For contexts holding an RSA-alt key, use
256 * \c mbedtls_pk_setup_rsa_alt() instead.
258 int mbedtls_pk_setup( mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info );
260 #if defined(MBEDTLS_USE_PSA_CRYPTO)
262 * \brief Initialize a PK context to wrap a PSA key slot.
264 * \note This function replaces mbedtls_pk_setup() for contexts
265 * that wrap a (possibly opaque) PSA key slot instead of
266 * storing and manipulating the key material directly.
268 * \param ctx The context to initialize. It must be empty (type NONE).
269 * \param key The PSA key slot to wrap, which must hold an ECC key pair
272 * \note The wrapped key slot must remain valid as long as the
273 * wrapping PK context is in use, that is at least between
274 * the point this function is called and the point
275 * mbedtls_pk_free() is called on this context. The wrapped
276 * key slot might then be independently used or destroyed.
278 * \note This function is currently only available for ECC key
279 * pairs (that is, ECC keys containing private key material).
280 * Support for other key types may be added later.
282 * \return \c 0 on success.
283 * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input
284 * (context already used, invalid key slot).
285 * \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the key is not an
287 * \return #MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
289 int mbedtls_pk_setup_opaque( mbedtls_pk_context *ctx, const psa_key_handle_t key );
290 #endif /* MBEDTLS_USE_PSA_CRYPTO */
292 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
294 * \brief Initialize an RSA-alt context
296 * \param ctx Context to initialize. It must not have been set
297 * up yet (type #MBEDTLS_PK_NONE).
298 * \param key RSA key pointer
299 * \param decrypt_func Decryption function
300 * \param sign_func Signing function
301 * \param key_len_func Function returning key length in bytes
303 * \return 0 on success, or MBEDTLS_ERR_PK_BAD_INPUT_DATA if the
304 * context wasn't already initialized as RSA_ALT.
306 * \note This function replaces \c mbedtls_pk_setup() for RSA-alt.
308 int mbedtls_pk_setup_rsa_alt( mbedtls_pk_context *ctx, void * key,
309 mbedtls_pk_rsa_alt_decrypt_func decrypt_func,
310 mbedtls_pk_rsa_alt_sign_func sign_func,
311 mbedtls_pk_rsa_alt_key_len_func key_len_func );
312 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
315 * \brief Get the size in bits of the underlying key
317 * \param ctx The context to query. It must have been initialized.
319 * \return Key size in bits, or 0 on error
321 size_t mbedtls_pk_get_bitlen( const mbedtls_pk_context *ctx );
324 * \brief Get the length in bytes of the underlying key
326 * \param ctx The context to query. It must have been initialized.
328 * \return Key length in bytes, or 0 on error
330 static inline size_t mbedtls_pk_get_len( const mbedtls_pk_context *ctx )
332 return( ( mbedtls_pk_get_bitlen( ctx ) + 7 ) / 8 );
336 * \brief Tell if a context can do the operation given by type
338 * \param ctx The context to query. It must have been initialized.
339 * \param type The desired type.
341 * \return 1 if the context can do operations on the given type.
342 * \return 0 if the context cannot do the operations on the given
343 * type. This is always the case for a context that has
344 * been initialized but not set up, or that has been
345 * cleared with mbedtls_pk_free().
347 int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type );
350 * \brief Verify signature (including padding if relevant).
352 * \param ctx The PK context to use. It must have been set up.
353 * \param md_alg Hash algorithm used (see notes)
354 * \param hash Hash of the message to sign
355 * \param hash_len Hash length or 0 (see notes)
356 * \param sig Signature to verify
357 * \param sig_len Signature length
359 * \return 0 on success (signature is valid),
360 * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid
361 * signature in sig but its length is less than \p siglen,
362 * or a specific error code.
364 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
365 * Use \c mbedtls_pk_verify_ext( MBEDTLS_PK_RSASSA_PSS, ... )
366 * to verify RSASSA_PSS signatures.
368 * \note If hash_len is 0, then the length associated with md_alg
369 * is used instead, or an error returned if it is invalid.
371 * \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
373 int mbedtls_pk_verify( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
374 const unsigned char *hash, size_t hash_len,
375 const unsigned char *sig, size_t sig_len );
378 * \brief Restartable version of \c mbedtls_pk_verify()
380 * \note Performs the same job as \c mbedtls_pk_verify(), but can
381 * return early and restart according to the limit set with
382 * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
383 * operations. For RSA, same as \c mbedtls_pk_verify().
385 * \param ctx The PK context to use. It must have been set up.
386 * \param md_alg Hash algorithm used (see notes)
387 * \param hash Hash of the message to sign
388 * \param hash_len Hash length or 0 (see notes)
389 * \param sig Signature to verify
390 * \param sig_len Signature length
391 * \param rs_ctx Restart context (NULL to disable restart)
393 * \return See \c mbedtls_pk_verify(), or
394 * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
395 * operations was reached: see \c mbedtls_ecp_set_max_ops().
397 int mbedtls_pk_verify_restartable( mbedtls_pk_context *ctx,
398 mbedtls_md_type_t md_alg,
399 const unsigned char *hash, size_t hash_len,
400 const unsigned char *sig, size_t sig_len,
401 mbedtls_pk_restart_ctx *rs_ctx );
404 * \brief Verify signature, with options.
405 * (Includes verification of the padding depending on type.)
407 * \param type Signature type (inc. possible padding type) to verify
408 * \param options Pointer to type-specific options, or NULL
409 * \param ctx The PK context to use. It must have been set up.
410 * \param md_alg Hash algorithm used (see notes)
411 * \param hash Hash of the message to sign
412 * \param hash_len Hash length or 0 (see notes)
413 * \param sig Signature to verify
414 * \param sig_len Signature length
416 * \return 0 on success (signature is valid),
417 * #MBEDTLS_ERR_PK_TYPE_MISMATCH if the PK context can't be
418 * used for this type of signatures,
419 * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid
420 * signature in sig but its length is less than \p siglen,
421 * or a specific error code.
423 * \note If hash_len is 0, then the length associated with md_alg
424 * is used instead, or an error returned if it is invalid.
426 * \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
428 * \note If type is MBEDTLS_PK_RSASSA_PSS, then options must point
429 * to a mbedtls_pk_rsassa_pss_options structure,
430 * otherwise it must be NULL.
432 int mbedtls_pk_verify_ext( mbedtls_pk_type_t type, const void *options,
433 mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
434 const unsigned char *hash, size_t hash_len,
435 const unsigned char *sig, size_t sig_len );
438 * \brief Make signature, including padding if relevant.
440 * \param ctx The PK context to use. It must have been set up
441 * with a private key.
442 * \param md_alg Hash algorithm used (see notes)
443 * \param hash Hash of the message to sign
444 * \param hash_len Hash length or 0 (see notes)
445 * \param sig Place to write the signature
446 * \param sig_len Number of bytes written
447 * \param f_rng RNG function
448 * \param p_rng RNG parameter
450 * \return 0 on success, or a specific error code.
452 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
453 * There is no interface in the PK module to make RSASSA-PSS
456 * \note If hash_len is 0, then the length associated with md_alg
457 * is used instead, or an error returned if it is invalid.
459 * \note For RSA, md_alg may be MBEDTLS_MD_NONE if hash_len != 0.
460 * For ECDSA, md_alg may never be MBEDTLS_MD_NONE.
462 int mbedtls_pk_sign( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
463 const unsigned char *hash, size_t hash_len,
464 unsigned char *sig, size_t *sig_len,
465 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
468 * \brief Restartable version of \c mbedtls_pk_sign()
470 * \note Performs the same job as \c mbedtls_pk_sign(), but can
471 * return early and restart according to the limit set with
472 * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
473 * operations. For RSA, same as \c mbedtls_pk_sign().
475 * \param ctx The PK context to use. It must have been set up
476 * with a private key.
477 * \param md_alg Hash algorithm used (see notes)
478 * \param hash Hash of the message to sign
479 * \param hash_len Hash length or 0 (see notes)
480 * \param sig Place to write the signature
481 * \param sig_len Number of bytes written
482 * \param f_rng RNG function
483 * \param p_rng RNG parameter
484 * \param rs_ctx Restart context (NULL to disable restart)
486 * \return See \c mbedtls_pk_sign(), or
487 * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
488 * operations was reached: see \c mbedtls_ecp_set_max_ops().
490 int mbedtls_pk_sign_restartable( mbedtls_pk_context *ctx,
491 mbedtls_md_type_t md_alg,
492 const unsigned char *hash, size_t hash_len,
493 unsigned char *sig, size_t *sig_len,
494 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
495 mbedtls_pk_restart_ctx *rs_ctx );
498 * \brief Decrypt message (including padding if relevant).
500 * \param ctx The PK context to use. It must have been set up
501 * with a private key.
502 * \param input Input to decrypt
503 * \param ilen Input size
504 * \param output Decrypted output
505 * \param olen Decrypted message length
506 * \param osize Size of the output buffer
507 * \param f_rng RNG function
508 * \param p_rng RNG parameter
510 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
512 * \return 0 on success, or a specific error code.
514 int mbedtls_pk_decrypt( mbedtls_pk_context *ctx,
515 const unsigned char *input, size_t ilen,
516 unsigned char *output, size_t *olen, size_t osize,
517 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
520 * \brief Encrypt message (including padding if relevant).
522 * \param ctx The PK context to use. It must have been set up.
523 * \param input Message to encrypt
524 * \param ilen Message size
525 * \param output Encrypted output
526 * \param olen Encrypted output length
527 * \param osize Size of the output buffer
528 * \param f_rng RNG function
529 * \param p_rng RNG parameter
531 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
533 * \return 0 on success, or a specific error code.
535 int mbedtls_pk_encrypt( mbedtls_pk_context *ctx,
536 const unsigned char *input, size_t ilen,
537 unsigned char *output, size_t *olen, size_t osize,
538 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
541 * \brief Check if a public-private pair of keys matches.
543 * \param pub Context holding a public key.
544 * \param prv Context holding a private (and public) key.
546 * \return \c 0 on success (keys were checked and match each other).
547 * \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the keys could not
548 * be checked - in that case they may or may not match.
549 * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA if a context is invalid.
550 * \return Another non-zero value if the keys do not match.
552 int mbedtls_pk_check_pair( const mbedtls_pk_context *pub, const mbedtls_pk_context *prv );
555 * \brief Export debug information
557 * \param ctx The PK context to use. It must have been initialized.
558 * \param items Place to write debug items
560 * \return 0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
562 int mbedtls_pk_debug( const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items );
565 * \brief Access the type name
567 * \param ctx The PK context to use. It must have been initialized.
569 * \return Type name on success, or "invalid PK"
571 const char * mbedtls_pk_get_name( const mbedtls_pk_context *ctx );
574 * \brief Get the key type
576 * \param ctx The PK context to use. It must have been initialized.
578 * \return Type on success.
579 * \return #MBEDTLS_PK_NONE for a context that has not been set up.
581 mbedtls_pk_type_t mbedtls_pk_get_type( const mbedtls_pk_context *ctx );
583 #if defined(MBEDTLS_PK_PARSE_C)
584 /** \ingroup pk_module */
586 * \brief Parse a private key in PEM or DER format
588 * \param ctx The PK context to fill. It must have been initialized
590 * \param key Input buffer to parse.
591 * The buffer must contain the input exactly, with no
592 * extra trailing material. For PEM, the buffer must
593 * contain a null-terminated string.
594 * \param keylen Size of \b key in bytes.
595 * For PEM data, this includes the terminating null byte,
596 * so \p keylen must be equal to `strlen(key) + 1`.
597 * \param pwd Optional password for decryption.
598 * Pass \c NULL if expecting a non-encrypted key.
599 * Pass a string of \p pwdlen bytes if expecting an encrypted
600 * key; a non-encrypted key will also be accepted.
601 * The empty password is not supported.
602 * \param pwdlen Size of the password in bytes.
603 * Ignored if \p pwd is \c NULL.
605 * \note On entry, ctx must be empty, either freshly initialised
606 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
607 * specific key type, check the result with mbedtls_pk_can_do().
609 * \note The key is also checked for correctness.
611 * \return 0 if successful, or a specific PK or PEM error code
613 int mbedtls_pk_parse_key( mbedtls_pk_context *ctx,
614 const unsigned char *key, size_t keylen,
615 const unsigned char *pwd, size_t pwdlen );
617 /** \ingroup pk_module */
619 * \brief Parse a public key in PEM or DER format
621 * \param ctx The PK context to fill. It must have been initialized
623 * \param key Input buffer to parse.
624 * The buffer must contain the input exactly, with no
625 * extra trailing material. For PEM, the buffer must
626 * contain a null-terminated string.
627 * \param keylen Size of \b key in bytes.
628 * For PEM data, this includes the terminating null byte,
629 * so \p keylen must be equal to `strlen(key) + 1`.
631 * \note On entry, ctx must be empty, either freshly initialised
632 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
633 * specific key type, check the result with mbedtls_pk_can_do().
635 * \note The key is also checked for correctness.
637 * \return 0 if successful, or a specific PK or PEM error code
639 int mbedtls_pk_parse_public_key( mbedtls_pk_context *ctx,
640 const unsigned char *key, size_t keylen );
642 #if defined(MBEDTLS_FS_IO)
643 /** \ingroup pk_module */
645 * \brief Load and parse a private key
647 * \param ctx The PK context to fill. It must have been initialized
649 * \param path filename to read the private key from
650 * \param password Optional password to decrypt the file.
651 * Pass \c NULL if expecting a non-encrypted key.
652 * Pass a null-terminated string if expecting an encrypted
653 * key; a non-encrypted key will also be accepted.
654 * The empty password is not supported.
656 * \note On entry, ctx must be empty, either freshly initialised
657 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
658 * specific key type, check the result with mbedtls_pk_can_do().
660 * \note The key is also checked for correctness.
662 * \return 0 if successful, or a specific PK or PEM error code
664 int mbedtls_pk_parse_keyfile( mbedtls_pk_context *ctx,
665 const char *path, const char *password );
667 /** \ingroup pk_module */
669 * \brief Load and parse a public key
671 * \param ctx The PK context to fill. It must have been initialized
673 * \param path filename to read the public key from
675 * \note On entry, ctx must be empty, either freshly initialised
676 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If
677 * you need a specific key type, check the result with
678 * mbedtls_pk_can_do().
680 * \note The key is also checked for correctness.
682 * \return 0 if successful, or a specific PK or PEM error code
684 int mbedtls_pk_parse_public_keyfile( mbedtls_pk_context *ctx, const char *path );
685 #endif /* MBEDTLS_FS_IO */
686 #endif /* MBEDTLS_PK_PARSE_C */
688 #if defined(MBEDTLS_PK_WRITE_C)
690 * \brief Write a private key to a PKCS#1 or SEC1 DER structure
691 * Note: data is written at the end of the buffer! Use the
692 * return value to determine where you should start
695 * \param ctx PK context which must contain a valid private key.
696 * \param buf buffer to write to
697 * \param size size of the buffer
699 * \return length of data written if successful, or a specific
702 int mbedtls_pk_write_key_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
705 * \brief Write a public key to a SubjectPublicKeyInfo DER structure
706 * Note: data is written at the end of the buffer! Use the
707 * return value to determine where you should start
710 * \param ctx PK context which must contain a valid public or private key.
711 * \param buf buffer to write to
712 * \param size size of the buffer
714 * \return length of data written if successful, or a specific
717 int mbedtls_pk_write_pubkey_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
719 #if defined(MBEDTLS_PEM_WRITE_C)
721 * \brief Write a public key to a PEM string
723 * \param ctx PK context which must contain a valid public or private key.
724 * \param buf Buffer to write to. The output includes a
725 * terminating null byte.
726 * \param size Size of the buffer in bytes.
728 * \return 0 if successful, or a specific error code
730 int mbedtls_pk_write_pubkey_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
733 * \brief Write a private key to a PKCS#1 or SEC1 PEM string
735 * \param ctx PK context which must contain a valid private key.
736 * \param buf Buffer to write to. The output includes a
737 * terminating null byte.
738 * \param size Size of the buffer in bytes.
740 * \return 0 if successful, or a specific error code
742 int mbedtls_pk_write_key_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
743 #endif /* MBEDTLS_PEM_WRITE_C */
744 #endif /* MBEDTLS_PK_WRITE_C */
747 * WARNING: Low-level functions. You probably do not want to use these unless
748 * you are certain you do ;)
751 #if defined(MBEDTLS_PK_PARSE_C)
753 * \brief Parse a SubjectPublicKeyInfo DER structure
755 * \param p the position in the ASN.1 data
756 * \param end end of the buffer
757 * \param pk The PK context to fill. It must have been initialized
760 * \return 0 if successful, or a specific PK error code
762 int mbedtls_pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
763 mbedtls_pk_context *pk );
764 #endif /* MBEDTLS_PK_PARSE_C */
766 #if defined(MBEDTLS_PK_WRITE_C)
768 * \brief Write a subjectPublicKey to ASN.1 data
769 * Note: function works backwards in data buffer
771 * \param p reference to current position pointer
772 * \param start start of the buffer (for bounds-checking)
773 * \param key PK context which must contain a valid public or private key.
775 * \return the length written or a negative error code
777 int mbedtls_pk_write_pubkey( unsigned char **p, unsigned char *start,
778 const mbedtls_pk_context *key );
779 #endif /* MBEDTLS_PK_WRITE_C */
782 * Internal module functions. You probably do not want to use these unless you
785 #if defined(MBEDTLS_FS_IO)
786 int mbedtls_pk_load_file( const char *path, unsigned char **buf, size_t *n );
789 #if defined(MBEDTLS_USE_PSA_CRYPTO)
791 * \brief Turn an EC key into an Opaque one
793 * \warning This is a temporary utility function for tests. It might
794 * change or be removed at any time without notice.
796 * \note Only ECDSA keys are supported so far. Signing with the
797 * specified hash is the only allowed use of that key.
799 * \param pk Input: the EC key to transfer to a PSA key slot.
800 * Output: a PK context wrapping that PSA key slot.
801 * \param slot Output: the chosen slot for storing the key.
802 * It's the caller's responsibility to destroy that slot
803 * after calling mbedtls_pk_free() on the PK context.
804 * \param hash_alg The hash algorithm to allow for use with that key.
806 * \return \c 0 if successful.
807 * \return An Mbed TLS error code otherwise.
809 int mbedtls_pk_wrap_as_opaque( mbedtls_pk_context *pk,
810 psa_key_handle_t *slot,
811 psa_algorithm_t hash_alg );
812 #endif /* MBEDTLS_USE_PSA_CRYPTO */
818 #endif /* MBEDTLS_PK_H */