1 /**
2 * \file pk.h
3 *
4 * \brief Public Key abstraction layer
5 */
6 /*
7 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
8 * SPDX-License-Identifier: Apache-2.0
9 *
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
13 *
14 * http://www.apache.org/licenses/LICENSE-2.0
15 *
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.
21 *
22 * This file is part of mbed TLS (https://tls.mbed.org)
23 */
24
25 #ifndef MBEDTLS_PK_H
26 #define MBEDTLS_PK_H
27
28 #if !defined(MBEDTLS_CONFIG_FILE)
29 #include "config.h"
30 #else
31 #include MBEDTLS_CONFIG_FILE
32 #endif
33
34 #include "md.h"
35
36 #if defined(MBEDTLS_RSA_C)
37 #include "rsa.h"
38 #endif
39
40 #if defined(MBEDTLS_ECP_C)
41 #include "ecp.h"
42 #endif
43
44 #if defined(MBEDTLS_ECDSA_C)
45 #include "ecdsa.h"
46 #endif
47
48 #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
49 !defined(inline) && !defined(__cplusplus)
50 #define inline __inline
51 #endif
52
53 #define MBEDTLS_ERR_PK_ALLOC_FAILED -0x3F80 /**< Memory allocation failed. */
54 #define MBEDTLS_ERR_PK_TYPE_MISMATCH -0x3F00 /**< Type mismatch, eg attempt to encrypt with an ECDSA key */
55 #define MBEDTLS_ERR_PK_BAD_INPUT_DATA -0x3E80 /**< Bad input parameters to function. */
56 #define MBEDTLS_ERR_PK_FILE_IO_ERROR -0x3E00 /**< Read/write of file failed. */
57 #define MBEDTLS_ERR_PK_KEY_INVALID_VERSION -0x3D80 /**< Unsupported key version */
58 #define MBEDTLS_ERR_PK_KEY_INVALID_FORMAT -0x3D00 /**< Invalid key tag or value. */
59 #define MBEDTLS_ERR_PK_UNKNOWN_PK_ALG -0x3C80 /**< Key algorithm is unsupported (only RSA and EC are supported). */
60 #define MBEDTLS_ERR_PK_PASSWORD_REQUIRED -0x3C00 /**< Private key password can't be empty. */
61 #define MBEDTLS_ERR_PK_PASSWORD_MISMATCH -0x3B80 /**< Given private key password does not allow for correct decryption. */
62 #define MBEDTLS_ERR_PK_INVALID_PUBKEY -0x3B00 /**< The pubkey tag or value is invalid (only RSA and EC are supported). */
63 #define MBEDTLS_ERR_PK_INVALID_ALG -0x3A80 /**< The algorithm tag or value is invalid. */
64 #define MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE -0x3A00 /**< Elliptic curve is unsupported (only NIST curves are supported). */
65 #define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE -0x3980 /**< Unavailable feature, e.g. RSA disabled for RSA key. */
66 #define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH -0x3900 /**< The buffer contains a valid signature followed by more data. */
67
68 /* MBEDTLS_ERR_PK_HW_ACCEL_FAILED is deprecated and should not be used. */
69 #define MBEDTLS_ERR_PK_HW_ACCEL_FAILED -0x3880 /**< PK hardware accelerator failed. */
70
71 #ifdef __cplusplus
72 extern "C" {
73 #endif
74
75 /**
76 * \brief Public key types
77 */
78 typedef enum {
79 MBEDTLS_PK_NONE=0,
80 MBEDTLS_PK_RSA,
81 MBEDTLS_PK_ECKEY,
82 MBEDTLS_PK_ECKEY_DH,
83 MBEDTLS_PK_ECDSA,
84 MBEDTLS_PK_RSA_ALT,
85 MBEDTLS_PK_RSASSA_PSS,
86 } mbedtls_pk_type_t;
87
88 /**
89 * \brief Options for RSASSA-PSS signature verification.
90 * See \c mbedtls_rsa_rsassa_pss_verify_ext()
91 */
92 typedef struct mbedtls_pk_rsassa_pss_options
93 {
94 mbedtls_md_type_t mgf1_hash_id;
95 int expected_salt_len;
96
97 } mbedtls_pk_rsassa_pss_options;
98
99 /**
100 * \brief Types for interfacing with the debug module
101 */
102 typedef enum
103 {
104 MBEDTLS_PK_DEBUG_NONE = 0,
105 MBEDTLS_PK_DEBUG_MPI,
106 MBEDTLS_PK_DEBUG_ECP,
107 } mbedtls_pk_debug_type;
108
109 /**
110 * \brief Item to send to the debug module
111 */
112 typedef struct mbedtls_pk_debug_item
113 {
114 mbedtls_pk_debug_type type;
115 const char *name;
116 void *value;
117 } mbedtls_pk_debug_item;
118
119 /** Maximum number of item send for debugging, plus 1 */
120 #define MBEDTLS_PK_DEBUG_MAX_ITEMS 3
121
122 /**
123 * \brief Public key information and operations
124 */
125 typedef struct mbedtls_pk_info_t mbedtls_pk_info_t;
126
127 /**
128 * \brief Public key container
129 */
130 typedef struct mbedtls_pk_context
131 {
132 const mbedtls_pk_info_t * pk_info; /**< Public key information */
133 void * pk_ctx; /**< Underlying public key context */
134 } mbedtls_pk_context;
135
136 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
137 /**
138 * \brief Context for resuming operations
139 */
140 typedef struct
141 {
142 const mbedtls_pk_info_t * pk_info; /**< Public key information */
143 void * rs_ctx; /**< Underlying restart context */
144 } mbedtls_pk_restart_ctx;
145 #else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
146 /* Now we can declare functions that take a pointer to that */
147 typedef void mbedtls_pk_restart_ctx;
148 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
149
150 #if defined(MBEDTLS_RSA_C)
151 /**
152 * Quick access to an RSA context inside a PK context.
153 *
154 * \warning You must make sure the PK context actually holds an RSA context
155 * before using this function!
156 */
mbedtls_pk_rsa(const mbedtls_pk_context pk)157 static inline mbedtls_rsa_context *mbedtls_pk_rsa( const mbedtls_pk_context pk )
158 {
159 return( (mbedtls_rsa_context *) (pk).pk_ctx );
160 }
161 #endif /* MBEDTLS_RSA_C */
162
163 #if defined(MBEDTLS_ECP_C)
164 /**
165 * Quick access to an EC context inside a PK context.
166 *
167 * \warning You must make sure the PK context actually holds an EC context
168 * before using this function!
169 */
mbedtls_pk_ec(const mbedtls_pk_context pk)170 static inline mbedtls_ecp_keypair *mbedtls_pk_ec( const mbedtls_pk_context pk )
171 {
172 return( (mbedtls_ecp_keypair *) (pk).pk_ctx );
173 }
174 #endif /* MBEDTLS_ECP_C */
175
176 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
177 /**
178 * \brief Types for RSA-alt abstraction
179 */
180 typedef int (*mbedtls_pk_rsa_alt_decrypt_func)( void *ctx, int mode, size_t *olen,
181 const unsigned char *input, unsigned char *output,
182 size_t output_max_len );
183 typedef int (*mbedtls_pk_rsa_alt_sign_func)( void *ctx,
184 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
185 int mode, mbedtls_md_type_t md_alg, unsigned int hashlen,
186 const unsigned char *hash, unsigned char *sig );
187 typedef size_t (*mbedtls_pk_rsa_alt_key_len_func)( void *ctx );
188 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
189
190 /**
191 * \brief Return information associated with the given PK type
192 *
193 * \param pk_type PK type to search for.
194 *
195 * \return The PK info associated with the type or NULL if not found.
196 */
197 const mbedtls_pk_info_t *mbedtls_pk_info_from_type( mbedtls_pk_type_t pk_type );
198
199 /**
200 * \brief Initialize a #mbedtls_pk_context (as NONE).
201 *
202 * \param ctx The context to initialize.
203 * This must not be \c NULL.
204 */
205 void mbedtls_pk_init( mbedtls_pk_context *ctx );
206
207 /**
208 * \brief Free the components of a #mbedtls_pk_context.
209 *
210 * \param ctx The context to clear. It must have been initialized.
211 * If this is \c NULL, this function does nothing.
212 */
213 void mbedtls_pk_free( mbedtls_pk_context *ctx );
214
215 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
216 /**
217 * \brief Initialize a restart context
218 *
219 * \param ctx The context to initialize.
220 * This must not be \c NULL.
221 */
222 void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx );
223
224 /**
225 * \brief Free the components of a restart context
226 *
227 * \param ctx The context to clear. It must have been initialized.
228 * If this is \c NULL, this function does nothing.
229 */
230 void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx );
231 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
232
233 /**
234 * \brief Initialize a PK context with the information given
235 * and allocates the type-specific PK subcontext.
236 *
237 * \param ctx Context to initialize. It must not have been set
238 * up yet (type #MBEDTLS_PK_NONE).
239 * \param info Information to use
240 *
241 * \return 0 on success,
242 * MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input,
243 * MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
244 *
245 * \note For contexts holding an RSA-alt key, use
246 * \c mbedtls_pk_setup_rsa_alt() instead.
247 */
248 int mbedtls_pk_setup( mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info );
249
250 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
251 /**
252 * \brief Initialize an RSA-alt context
253 *
254 * \param ctx Context to initialize. It must not have been set
255 * up yet (type #MBEDTLS_PK_NONE).
256 * \param key RSA key pointer
257 * \param decrypt_func Decryption function
258 * \param sign_func Signing function
259 * \param key_len_func Function returning key length in bytes
260 *
261 * \return 0 on success, or MBEDTLS_ERR_PK_BAD_INPUT_DATA if the
262 * context wasn't already initialized as RSA_ALT.
263 *
264 * \note This function replaces \c mbedtls_pk_setup() for RSA-alt.
265 */
266 int mbedtls_pk_setup_rsa_alt( mbedtls_pk_context *ctx, void * key,
267 mbedtls_pk_rsa_alt_decrypt_func decrypt_func,
268 mbedtls_pk_rsa_alt_sign_func sign_func,
269 mbedtls_pk_rsa_alt_key_len_func key_len_func );
270 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
271
272 /**
273 * \brief Get the size in bits of the underlying key
274 *
275 * \param ctx The context to query. It must have been initialized.
276 *
277 * \return Key size in bits, or 0 on error
278 */
279 size_t mbedtls_pk_get_bitlen( const mbedtls_pk_context *ctx );
280
281 /**
282 * \brief Get the length in bytes of the underlying key
283 *
284 * \param ctx The context to query. It must have been initialized.
285 *
286 * \return Key length in bytes, or 0 on error
287 */
mbedtls_pk_get_len(const mbedtls_pk_context * ctx)288 static inline size_t mbedtls_pk_get_len( const mbedtls_pk_context *ctx )
289 {
290 return( ( mbedtls_pk_get_bitlen( ctx ) + 7 ) / 8 );
291 }
292
293 /**
294 * \brief Tell if a context can do the operation given by type
295 *
296 * \param ctx The context to query. It must have been initialized.
297 * \param type The desired type.
298 *
299 * \return 1 if the context can do operations on the given type.
300 * \return 0 if the context cannot do the operations on the given
301 * type. This is always the case for a context that has
302 * been initialized but not set up, or that has been
303 * cleared with mbedtls_pk_free().
304 */
305 int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type );
306
307 /**
308 * \brief Verify signature (including padding if relevant).
309 *
310 * \param ctx The PK context to use. It must have been set up.
311 * \param md_alg Hash algorithm used (see notes)
312 * \param hash Hash of the message to sign
313 * \param hash_len Hash length or 0 (see notes)
314 * \param sig Signature to verify
315 * \param sig_len Signature length
316 *
317 * \return 0 on success (signature is valid),
318 * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid
319 * signature in sig but its length is less than \p siglen,
320 * or a specific error code.
321 *
322 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
323 * Use \c mbedtls_pk_verify_ext( MBEDTLS_PK_RSASSA_PSS, ... )
324 * to verify RSASSA_PSS signatures.
325 *
326 * \note If hash_len is 0, then the length associated with md_alg
327 * is used instead, or an error returned if it is invalid.
328 *
329 * \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
330 */
331 int mbedtls_pk_verify( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
332 const unsigned char *hash, size_t hash_len,
333 const unsigned char *sig, size_t sig_len );
334
335 /**
336 * \brief Restartable version of \c mbedtls_pk_verify()
337 *
338 * \note Performs the same job as \c mbedtls_pk_verify(), but can
339 * return early and restart according to the limit set with
340 * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
341 * operations. For RSA, same as \c mbedtls_pk_verify().
342 *
343 * \param ctx The PK context to use. It must have been set up.
344 * \param md_alg Hash algorithm used (see notes)
345 * \param hash Hash of the message to sign
346 * \param hash_len Hash length or 0 (see notes)
347 * \param sig Signature to verify
348 * \param sig_len Signature length
349 * \param rs_ctx Restart context (NULL to disable restart)
350 *
351 * \return See \c mbedtls_pk_verify(), or
352 * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
353 * operations was reached: see \c mbedtls_ecp_set_max_ops().
354 */
355 int mbedtls_pk_verify_restartable( mbedtls_pk_context *ctx,
356 mbedtls_md_type_t md_alg,
357 const unsigned char *hash, size_t hash_len,
358 const unsigned char *sig, size_t sig_len,
359 mbedtls_pk_restart_ctx *rs_ctx );
360
361 /**
362 * \brief Verify signature, with options.
363 * (Includes verification of the padding depending on type.)
364 *
365 * \param type Signature type (inc. possible padding type) to verify
366 * \param options Pointer to type-specific options, or NULL
367 * \param ctx The PK context to use. It must have been set up.
368 * \param md_alg Hash algorithm used (see notes)
369 * \param hash Hash of the message to sign
370 * \param hash_len Hash length or 0 (see notes)
371 * \param sig Signature to verify
372 * \param sig_len Signature length
373 *
374 * \return 0 on success (signature is valid),
375 * #MBEDTLS_ERR_PK_TYPE_MISMATCH if the PK context can't be
376 * used for this type of signatures,
377 * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid
378 * signature in sig but its length is less than \p siglen,
379 * or a specific error code.
380 *
381 * \note If hash_len is 0, then the length associated with md_alg
382 * is used instead, or an error returned if it is invalid.
383 *
384 * \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
385 *
386 * \note If type is MBEDTLS_PK_RSASSA_PSS, then options must point
387 * to a mbedtls_pk_rsassa_pss_options structure,
388 * otherwise it must be NULL.
389 */
390 int mbedtls_pk_verify_ext( mbedtls_pk_type_t type, const void *options,
391 mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
392 const unsigned char *hash, size_t hash_len,
393 const unsigned char *sig, size_t sig_len );
394
395 /**
396 * \brief Make signature, including padding if relevant.
397 *
398 * \param ctx The PK context to use. It must have been set up
399 * with a private key.
400 * \param md_alg Hash algorithm used (see notes)
401 * \param hash Hash of the message to sign
402 * \param hash_len Hash length or 0 (see notes)
403 * \param sig Place to write the signature
404 * \param sig_len Number of bytes written
405 * \param f_rng RNG function
406 * \param p_rng RNG parameter
407 *
408 * \return 0 on success, or a specific error code.
409 *
410 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
411 * There is no interface in the PK module to make RSASSA-PSS
412 * signatures yet.
413 *
414 * \note If hash_len is 0, then the length associated with md_alg
415 * is used instead, or an error returned if it is invalid.
416 *
417 * \note For RSA, md_alg may be MBEDTLS_MD_NONE if hash_len != 0.
418 * For ECDSA, md_alg may never be MBEDTLS_MD_NONE.
419 */
420 int mbedtls_pk_sign( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
421 const unsigned char *hash, size_t hash_len,
422 unsigned char *sig, size_t *sig_len,
423 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
424
425 /**
426 * \brief Restartable version of \c mbedtls_pk_sign()
427 *
428 * \note Performs the same job as \c mbedtls_pk_sign(), but can
429 * return early and restart according to the limit set with
430 * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
431 * operations. For RSA, same as \c mbedtls_pk_sign().
432 *
433 * \param ctx The PK context to use. It must have been set up
434 * with a private key.
435 * \param md_alg Hash algorithm used (see notes)
436 * \param hash Hash of the message to sign
437 * \param hash_len Hash length or 0 (see notes)
438 * \param sig Place to write the signature
439 * \param sig_len Number of bytes written
440 * \param f_rng RNG function
441 * \param p_rng RNG parameter
442 * \param rs_ctx Restart context (NULL to disable restart)
443 *
444 * \return See \c mbedtls_pk_sign(), or
445 * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
446 * operations was reached: see \c mbedtls_ecp_set_max_ops().
447 */
448 int mbedtls_pk_sign_restartable( mbedtls_pk_context *ctx,
449 mbedtls_md_type_t md_alg,
450 const unsigned char *hash, size_t hash_len,
451 unsigned char *sig, size_t *sig_len,
452 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
453 mbedtls_pk_restart_ctx *rs_ctx );
454
455 /**
456 * \brief Decrypt message (including padding if relevant).
457 *
458 * \param ctx The PK context to use. It must have been set up
459 * with a private key.
460 * \param input Input to decrypt
461 * \param ilen Input size
462 * \param output Decrypted output
463 * \param olen Decrypted message length
464 * \param osize Size of the output buffer
465 * \param f_rng RNG function
466 * \param p_rng RNG parameter
467 *
468 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
469 *
470 * \return 0 on success, or a specific error code.
471 */
472 int mbedtls_pk_decrypt( mbedtls_pk_context *ctx,
473 const unsigned char *input, size_t ilen,
474 unsigned char *output, size_t *olen, size_t osize,
475 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
476
477 /**
478 * \brief Encrypt message (including padding if relevant).
479 *
480 * \param ctx The PK context to use. It must have been set up.
481 * \param input Message to encrypt
482 * \param ilen Message size
483 * \param output Encrypted output
484 * \param olen Encrypted output length
485 * \param osize Size of the output buffer
486 * \param f_rng RNG function
487 * \param p_rng RNG parameter
488 *
489 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
490 *
491 * \return 0 on success, or a specific error code.
492 */
493 int mbedtls_pk_encrypt( mbedtls_pk_context *ctx,
494 const unsigned char *input, size_t ilen,
495 unsigned char *output, size_t *olen, size_t osize,
496 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
497
498 /**
499 * \brief Check if a public-private pair of keys matches.
500 *
501 * \param pub Context holding a public key.
502 * \param prv Context holding a private (and public) key.
503 *
504 * \return 0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
505 */
506 int mbedtls_pk_check_pair( const mbedtls_pk_context *pub, const mbedtls_pk_context *prv );
507
508 /**
509 * \brief Export debug information
510 *
511 * \param ctx The PK context to use. It must have been initialized.
512 * \param items Place to write debug items
513 *
514 * \return 0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
515 */
516 int mbedtls_pk_debug( const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items );
517
518 /**
519 * \brief Access the type name
520 *
521 * \param ctx The PK context to use. It must have been initialized.
522 *
523 * \return Type name on success, or "invalid PK"
524 */
525 const char * mbedtls_pk_get_name( const mbedtls_pk_context *ctx );
526
527 /**
528 * \brief Get the key type
529 *
530 * \param ctx The PK context to use. It must have been initialized.
531 *
532 * \return Type on success.
533 * \return #MBEDTLS_PK_NONE for a context that has not been set up.
534 */
535 mbedtls_pk_type_t mbedtls_pk_get_type( const mbedtls_pk_context *ctx );
536
537 #if defined(MBEDTLS_PK_PARSE_C)
538 /** \ingroup pk_module */
539 /**
540 * \brief Parse a private key in PEM or DER format
541 *
542 * \param ctx The PK context to fill. It must have been initialized
543 * but not set up.
544 * \param key Input buffer to parse.
545 * The buffer must contain the input exactly, with no
546 * extra trailing material. For PEM, the buffer must
547 * contain a null-terminated string.
548 * \param keylen Size of \b key in bytes.
549 * For PEM data, this includes the terminating null byte,
550 * so \p keylen must be equal to `strlen(key) + 1`.
551 * \param pwd Optional password for decryption.
552 * Pass \c NULL if expecting a non-encrypted key.
553 * Pass a string of \p pwdlen bytes if expecting an encrypted
554 * key; a non-encrypted key will also be accepted.
555 * The empty password is not supported.
556 * \param pwdlen Size of the password in bytes.
557 * Ignored if \p pwd is \c NULL.
558 *
559 * \note On entry, ctx must be empty, either freshly initialised
560 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
561 * specific key type, check the result with mbedtls_pk_can_do().
562 *
563 * \note The key is also checked for correctness.
564 *
565 * \return 0 if successful, or a specific PK or PEM error code
566 */
567 int mbedtls_pk_parse_key( mbedtls_pk_context *ctx,
568 const unsigned char *key, size_t keylen,
569 const unsigned char *pwd, size_t pwdlen );
570
571 /** \ingroup pk_module */
572 /**
573 * \brief Parse a public key in PEM or DER format
574 *
575 * \param ctx The PK context to fill. It must have been initialized
576 * but not set up.
577 * \param key Input buffer to parse.
578 * The buffer must contain the input exactly, with no
579 * extra trailing material. For PEM, the buffer must
580 * contain a null-terminated string.
581 * \param keylen Size of \b key in bytes.
582 * For PEM data, this includes the terminating null byte,
583 * so \p keylen must be equal to `strlen(key) + 1`.
584 *
585 * \note On entry, ctx must be empty, either freshly initialised
586 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
587 * specific key type, check the result with mbedtls_pk_can_do().
588 *
589 * \note The key is also checked for correctness.
590 *
591 * \return 0 if successful, or a specific PK or PEM error code
592 */
593 int mbedtls_pk_parse_public_key( mbedtls_pk_context *ctx,
594 const unsigned char *key, size_t keylen );
595
596 #if defined(MBEDTLS_FS_IO)
597 /** \ingroup pk_module */
598 /**
599 * \brief Load and parse a private key
600 *
601 * \param ctx The PK context to fill. It must have been initialized
602 * but not set up.
603 * \param path filename to read the private key from
604 * \param password Optional password to decrypt the file.
605 * Pass \c NULL if expecting a non-encrypted key.
606 * Pass a null-terminated string if expecting an encrypted
607 * key; a non-encrypted key will also be accepted.
608 * The empty password is not supported.
609 *
610 * \note On entry, ctx must be empty, either freshly initialised
611 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
612 * specific key type, check the result with mbedtls_pk_can_do().
613 *
614 * \note The key is also checked for correctness.
615 *
616 * \return 0 if successful, or a specific PK or PEM error code
617 */
618 int mbedtls_pk_parse_keyfile( mbedtls_pk_context *ctx,
619 const char *path, const char *password );
620
621 /** \ingroup pk_module */
622 /**
623 * \brief Load and parse a public key
624 *
625 * \param ctx The PK context to fill. It must have been initialized
626 * but not set up.
627 * \param path filename to read the public key from
628 *
629 * \note On entry, ctx must be empty, either freshly initialised
630 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If
631 * you need a specific key type, check the result with
632 * mbedtls_pk_can_do().
633 *
634 * \note The key is also checked for correctness.
635 *
636 * \return 0 if successful, or a specific PK or PEM error code
637 */
638 int mbedtls_pk_parse_public_keyfile( mbedtls_pk_context *ctx, const char *path );
639 #endif /* MBEDTLS_FS_IO */
640 #endif /* MBEDTLS_PK_PARSE_C */
641
642 #if defined(MBEDTLS_PK_WRITE_C)
643 /**
644 * \brief Write a private key to a PKCS#1 or SEC1 DER structure
645 * Note: data is written at the end of the buffer! Use the
646 * return value to determine where you should start
647 * using the buffer
648 *
649 * \param ctx PK context which must contain a valid private key.
650 * \param buf buffer to write to
651 * \param size size of the buffer
652 *
653 * \return length of data written if successful, or a specific
654 * error code
655 */
656 int mbedtls_pk_write_key_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
657
658 /**
659 * \brief Write a public key to a SubjectPublicKeyInfo DER structure
660 * Note: data is written at the end of the buffer! Use the
661 * return value to determine where you should start
662 * using the buffer
663 *
664 * \param ctx PK context which must contain a valid public or private key.
665 * \param buf buffer to write to
666 * \param size size of the buffer
667 *
668 * \return length of data written if successful, or a specific
669 * error code
670 */
671 int mbedtls_pk_write_pubkey_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
672
673 #if defined(MBEDTLS_PEM_WRITE_C)
674 /**
675 * \brief Write a public key to a PEM string
676 *
677 * \param ctx PK context which must contain a valid public or private key.
678 * \param buf Buffer to write to. The output includes a
679 * terminating null byte.
680 * \param size Size of the buffer in bytes.
681 *
682 * \return 0 if successful, or a specific error code
683 */
684 int mbedtls_pk_write_pubkey_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
685
686 /**
687 * \brief Write a private key to a PKCS#1 or SEC1 PEM string
688 *
689 * \param ctx PK context which must contain a valid private key.
690 * \param buf Buffer to write to. The output includes a
691 * terminating null byte.
692 * \param size Size of the buffer in bytes.
693 *
694 * \return 0 if successful, or a specific error code
695 */
696 int mbedtls_pk_write_key_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
697 #endif /* MBEDTLS_PEM_WRITE_C */
698 #endif /* MBEDTLS_PK_WRITE_C */
699
700 /*
701 * WARNING: Low-level functions. You probably do not want to use these unless
702 * you are certain you do ;)
703 */
704
705 #if defined(MBEDTLS_PK_PARSE_C)
706 /**
707 * \brief Parse a SubjectPublicKeyInfo DER structure
708 *
709 * \param p the position in the ASN.1 data
710 * \param end end of the buffer
711 * \param pk The PK context to fill. It must have been initialized
712 * but not set up.
713 *
714 * \return 0 if successful, or a specific PK error code
715 */
716 int mbedtls_pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
717 mbedtls_pk_context *pk );
718 #endif /* MBEDTLS_PK_PARSE_C */
719
720 #if defined(MBEDTLS_PK_WRITE_C)
721 /**
722 * \brief Write a subjectPublicKey to ASN.1 data
723 * Note: function works backwards in data buffer
724 *
725 * \param p reference to current position pointer
726 * \param start start of the buffer (for bounds-checking)
727 * \param key PK context which must contain a valid public or private key.
728 *
729 * \return the length written or a negative error code
730 */
731 int mbedtls_pk_write_pubkey( unsigned char **p, unsigned char *start,
732 const mbedtls_pk_context *key );
733 #endif /* MBEDTLS_PK_WRITE_C */
734
735 /*
736 * Internal module functions. You probably do not want to use these unless you
737 * know you do.
738 */
739 #if defined(MBEDTLS_FS_IO)
740 int mbedtls_pk_load_file( const char *path, unsigned char **buf, size_t *n );
741 #endif
742
743 #ifdef __cplusplus
744 }
745 #endif
746
747 #endif /* MBEDTLS_PK_H */
748