1 /**
2 * \file pk.h
3 *
4 * \brief Public Key abstraction layer
5 */
6 /*
7 * Copyright The Mbed TLS Contributors
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
23 #ifndef MBEDTLS_PK_H
24 #define MBEDTLS_PK_H
25
26 #if !defined(MBEDTLS_CONFIG_FILE)
27 #include "mbedtls/config.h"
28 #else
29 #include MBEDTLS_CONFIG_FILE
30 #endif
31
32 #include "mbedtls/md.h"
33
34 #if defined(MBEDTLS_RSA_C)
35 #include "mbedtls/rsa.h"
36 #endif
37
38 #if defined(MBEDTLS_ECP_C)
39 #include "mbedtls/ecp.h"
40 #endif
41
42 #if defined(MBEDTLS_ECDSA_C)
43 #include "mbedtls/ecdsa.h"
44 #endif
45
46 #if defined(MBEDTLS_USE_PSA_CRYPTO)
47 #include "psa/crypto.h"
48 #endif
49
50 #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
51 !defined(inline) && !defined(__cplusplus)
52 #define inline __inline
53 #endif
54
55 /** Memory allocation failed. */
56 #define MBEDTLS_ERR_PK_ALLOC_FAILED -0x3F80
57 /** Type mismatch, eg attempt to encrypt with an ECDSA key */
58 #define MBEDTLS_ERR_PK_TYPE_MISMATCH -0x3F00
59 /** Bad input parameters to function. */
60 #define MBEDTLS_ERR_PK_BAD_INPUT_DATA -0x3E80
61 /** Read/write of file failed. */
62 #define MBEDTLS_ERR_PK_FILE_IO_ERROR -0x3E00
63 /** Unsupported key version */
64 #define MBEDTLS_ERR_PK_KEY_INVALID_VERSION -0x3D80
65 /** Invalid key tag or value. */
66 #define MBEDTLS_ERR_PK_KEY_INVALID_FORMAT -0x3D00
67 /** Key algorithm is unsupported (only RSA and EC are supported). */
68 #define MBEDTLS_ERR_PK_UNKNOWN_PK_ALG -0x3C80
69 /** Private key password can't be empty. */
70 #define MBEDTLS_ERR_PK_PASSWORD_REQUIRED -0x3C00
71 /** Given private key password does not allow for correct decryption. */
72 #define MBEDTLS_ERR_PK_PASSWORD_MISMATCH -0x3B80
73 /** The pubkey tag or value is invalid (only RSA and EC are supported). */
74 #define MBEDTLS_ERR_PK_INVALID_PUBKEY -0x3B00
75 /** The algorithm tag or value is invalid. */
76 #define MBEDTLS_ERR_PK_INVALID_ALG -0x3A80
77 /** Elliptic curve is unsupported (only NIST curves are supported). */
78 #define MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE -0x3A00
79 /** Unavailable feature, e.g. RSA disabled for RSA key. */
80 #define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE -0x3980
81 /** The buffer contains a valid signature followed by more data. */
82 #define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH -0x3900
83
84 /* MBEDTLS_ERR_PK_HW_ACCEL_FAILED is deprecated and should not be used. */
85 /** PK hardware accelerator failed. */
86 #define MBEDTLS_ERR_PK_HW_ACCEL_FAILED -0x3880
87
88 #ifdef __cplusplus
89 extern "C" {
90 #endif
91
92 /**
93 * \brief Public key types
94 */
95 typedef enum {
96 MBEDTLS_PK_NONE=0,
97 MBEDTLS_PK_RSA,
98 MBEDTLS_PK_ECKEY,
99 MBEDTLS_PK_ECKEY_DH,
100 MBEDTLS_PK_ECDSA,
101 MBEDTLS_PK_RSA_ALT,
102 MBEDTLS_PK_RSASSA_PSS,
103 MBEDTLS_PK_OPAQUE,
104 } mbedtls_pk_type_t;
105
106 /**
107 * \brief Options for RSASSA-PSS signature verification.
108 * See \c mbedtls_rsa_rsassa_pss_verify_ext()
109 */
110 typedef struct mbedtls_pk_rsassa_pss_options
111 {
112 mbedtls_md_type_t mgf1_hash_id;
113 int expected_salt_len;
114
115 } mbedtls_pk_rsassa_pss_options;
116
117 /**
118 * \brief Maximum size of a signature made by mbedtls_pk_sign().
119 */
120 /* We need to set MBEDTLS_PK_SIGNATURE_MAX_SIZE to the maximum signature
121 * size among the supported signature types. Do it by starting at 0,
122 * then incrementally increasing to be large enough for each supported
123 * signature mechanism.
124 *
125 * The resulting value can be 0, for example if MBEDTLS_ECDH_C is enabled
126 * (which allows the pk module to be included) but neither MBEDTLS_ECDSA_C
127 * nor MBEDTLS_RSA_C nor any opaque signature mechanism (PSA or RSA_ALT).
128 */
129 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE 0
130
131 #if ( defined(MBEDTLS_RSA_C) || defined(MBEDTLS_PK_RSA_ALT_SUPPORT) ) && \
132 MBEDTLS_MPI_MAX_SIZE > MBEDTLS_PK_SIGNATURE_MAX_SIZE
133 /* For RSA, the signature can be as large as the bignum module allows.
134 * For RSA_ALT, the signature size is not necessarily tied to what the
135 * bignum module can do, but in the absence of any specific setting,
136 * we use that (rsa_alt_sign_wrap in pk_wrap will check). */
137 #undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
138 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE MBEDTLS_MPI_MAX_SIZE
139 #endif
140
141 #if defined(MBEDTLS_ECDSA_C) && \
142 MBEDTLS_ECDSA_MAX_LEN > MBEDTLS_PK_SIGNATURE_MAX_SIZE
143 /* For ECDSA, the ecdsa module exports a constant for the maximum
144 * signature size. */
145 #undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
146 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE MBEDTLS_ECDSA_MAX_LEN
147 #endif
148
149 #if defined(MBEDTLS_USE_PSA_CRYPTO)
150 #if PSA_SIGNATURE_MAX_SIZE > MBEDTLS_PK_SIGNATURE_MAX_SIZE
151 /* PSA_SIGNATURE_MAX_SIZE is the maximum size of a signature made
152 * through the PSA API in the PSA representation. */
153 #undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
154 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE PSA_SIGNATURE_MAX_SIZE
155 #endif
156
157 #if PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE + 11 > MBEDTLS_PK_SIGNATURE_MAX_SIZE
158 /* The Mbed TLS representation is different for ECDSA signatures:
159 * PSA uses the raw concatenation of r and s,
160 * whereas Mbed TLS uses the ASN.1 representation (SEQUENCE of two INTEGERs).
161 * Add the overhead of ASN.1: up to (1+2) + 2 * (1+2+1) for the
162 * types, lengths (represented by up to 2 bytes), and potential leading
163 * zeros of the INTEGERs and the SEQUENCE. */
164 #undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
165 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE ( PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE + 11 )
166 #endif
167 #endif /* defined(MBEDTLS_USE_PSA_CRYPTO) */
168
169 /**
170 * \brief Types for interfacing with the debug module
171 */
172 typedef enum
173 {
174 MBEDTLS_PK_DEBUG_NONE = 0,
175 MBEDTLS_PK_DEBUG_MPI,
176 MBEDTLS_PK_DEBUG_ECP,
177 } mbedtls_pk_debug_type;
178
179 /**
180 * \brief Item to send to the debug module
181 */
182 typedef struct mbedtls_pk_debug_item
183 {
184 mbedtls_pk_debug_type type;
185 const char *name;
186 void *value;
187 } mbedtls_pk_debug_item;
188
189 /** Maximum number of item send for debugging, plus 1 */
190 #define MBEDTLS_PK_DEBUG_MAX_ITEMS 3
191
192 /**
193 * \brief Public key information and operations
194 */
195 typedef struct mbedtls_pk_info_t mbedtls_pk_info_t;
196
197 /**
198 * \brief Public key container
199 */
200 typedef struct mbedtls_pk_context
201 {
202 const mbedtls_pk_info_t * pk_info; /**< Public key information */
203 void * pk_ctx; /**< Underlying public key context */
204 } mbedtls_pk_context;
205
206 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
207 /**
208 * \brief Context for resuming operations
209 */
210 typedef struct
211 {
212 const mbedtls_pk_info_t * pk_info; /**< Public key information */
213 void * rs_ctx; /**< Underlying restart context */
214 } mbedtls_pk_restart_ctx;
215 #else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
216 /* Now we can declare functions that take a pointer to that */
217 typedef void mbedtls_pk_restart_ctx;
218 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
219
220 #if defined(MBEDTLS_RSA_C)
221 /**
222 * Quick access to an RSA context inside a PK context.
223 *
224 * \warning You must make sure the PK context actually holds an RSA context
225 * before using this function!
226 */
mbedtls_pk_rsa(const mbedtls_pk_context pk)227 static inline mbedtls_rsa_context *mbedtls_pk_rsa( const mbedtls_pk_context pk )
228 {
229 return( (mbedtls_rsa_context *) (pk).pk_ctx );
230 }
231 #endif /* MBEDTLS_RSA_C */
232
233 #if defined(MBEDTLS_ECP_C)
234 /**
235 * Quick access to an EC context inside a PK context.
236 *
237 * \warning You must make sure the PK context actually holds an EC context
238 * before using this function!
239 */
mbedtls_pk_ec(const mbedtls_pk_context pk)240 static inline mbedtls_ecp_keypair *mbedtls_pk_ec( const mbedtls_pk_context pk )
241 {
242 return( (mbedtls_ecp_keypair *) (pk).pk_ctx );
243 }
244 #endif /* MBEDTLS_ECP_C */
245
246 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
247 /**
248 * \brief Types for RSA-alt abstraction
249 */
250 typedef int (*mbedtls_pk_rsa_alt_decrypt_func)( void *ctx, int mode, size_t *olen,
251 const unsigned char *input, unsigned char *output,
252 size_t output_max_len );
253 typedef int (*mbedtls_pk_rsa_alt_sign_func)( void *ctx,
254 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
255 int mode, mbedtls_md_type_t md_alg, unsigned int hashlen,
256 const unsigned char *hash, unsigned char *sig );
257 typedef size_t (*mbedtls_pk_rsa_alt_key_len_func)( void *ctx );
258 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
259
260 /**
261 * \brief Return information associated with the given PK type
262 *
263 * \param pk_type PK type to search for.
264 *
265 * \return The PK info associated with the type or NULL if not found.
266 */
267 const mbedtls_pk_info_t *mbedtls_pk_info_from_type( mbedtls_pk_type_t pk_type );
268
269 /**
270 * \brief Initialize a #mbedtls_pk_context (as NONE).
271 *
272 * \param ctx The context to initialize.
273 * This must not be \c NULL.
274 */
275 void mbedtls_pk_init( mbedtls_pk_context *ctx );
276
277 /**
278 * \brief Free the components of a #mbedtls_pk_context.
279 *
280 * \param ctx The context to clear. It must have been initialized.
281 * If this is \c NULL, this function does nothing.
282 *
283 * \note For contexts that have been set up with
284 * mbedtls_pk_setup_opaque(), this does not free the underlying
285 * PSA key and you still need to call psa_destroy_key()
286 * independently if you want to destroy that key.
287 */
288 void mbedtls_pk_free( mbedtls_pk_context *ctx );
289
290 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
291 /**
292 * \brief Initialize a restart context
293 *
294 * \param ctx The context to initialize.
295 * This must not be \c NULL.
296 */
297 void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx );
298
299 /**
300 * \brief Free the components of a restart context
301 *
302 * \param ctx The context to clear. It must have been initialized.
303 * If this is \c NULL, this function does nothing.
304 */
305 void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx );
306 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
307
308 /**
309 * \brief Initialize a PK context with the information given
310 * and allocates the type-specific PK subcontext.
311 *
312 * \param ctx Context to initialize. It must not have been set
313 * up yet (type #MBEDTLS_PK_NONE).
314 * \param info Information to use
315 *
316 * \return 0 on success,
317 * MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input,
318 * MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
319 *
320 * \note For contexts holding an RSA-alt key, use
321 * \c mbedtls_pk_setup_rsa_alt() instead.
322 */
323 int mbedtls_pk_setup( mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info );
324
325 #if defined(MBEDTLS_USE_PSA_CRYPTO)
326 /**
327 * \brief Initialize a PK context to wrap a PSA key.
328 *
329 * \note This function replaces mbedtls_pk_setup() for contexts
330 * that wrap a (possibly opaque) PSA key instead of
331 * storing and manipulating the key material directly.
332 *
333 * \param ctx The context to initialize. It must be empty (type NONE).
334 * \param key The PSA key to wrap, which must hold an ECC key pair
335 * (see notes below).
336 *
337 * \note The wrapped key must remain valid as long as the
338 * wrapping PK context is in use, that is at least between
339 * the point this function is called and the point
340 * mbedtls_pk_free() is called on this context. The wrapped
341 * key might then be independently used or destroyed.
342 *
343 * \note This function is currently only available for ECC key
344 * pairs (that is, ECC keys containing private key material).
345 * Support for other key types may be added later.
346 *
347 * \return \c 0 on success.
348 * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input
349 * (context already used, invalid key identifier).
350 * \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the key is not an
351 * ECC key pair.
352 * \return #MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
353 */
354 int mbedtls_pk_setup_opaque( mbedtls_pk_context *ctx,
355 const psa_key_id_t key );
356 #endif /* MBEDTLS_USE_PSA_CRYPTO */
357
358 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
359 /**
360 * \brief Initialize an RSA-alt context
361 *
362 * \param ctx Context to initialize. It must not have been set
363 * up yet (type #MBEDTLS_PK_NONE).
364 * \param key RSA key pointer
365 * \param decrypt_func Decryption function
366 * \param sign_func Signing function
367 * \param key_len_func Function returning key length in bytes
368 *
369 * \return 0 on success, or MBEDTLS_ERR_PK_BAD_INPUT_DATA if the
370 * context wasn't already initialized as RSA_ALT.
371 *
372 * \note This function replaces \c mbedtls_pk_setup() for RSA-alt.
373 */
374 int mbedtls_pk_setup_rsa_alt( mbedtls_pk_context *ctx, void * key,
375 mbedtls_pk_rsa_alt_decrypt_func decrypt_func,
376 mbedtls_pk_rsa_alt_sign_func sign_func,
377 mbedtls_pk_rsa_alt_key_len_func key_len_func );
378 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
379
380 /**
381 * \brief Get the size in bits of the underlying key
382 *
383 * \param ctx The context to query. It must have been initialized.
384 *
385 * \return Key size in bits, or 0 on error
386 */
387 size_t mbedtls_pk_get_bitlen( const mbedtls_pk_context *ctx );
388
389 /**
390 * \brief Get the length in bytes of the underlying key
391 *
392 * \param ctx The context to query. It must have been initialized.
393 *
394 * \return Key length in bytes, or 0 on error
395 */
mbedtls_pk_get_len(const mbedtls_pk_context * ctx)396 static inline size_t mbedtls_pk_get_len( const mbedtls_pk_context *ctx )
397 {
398 return( ( mbedtls_pk_get_bitlen( ctx ) + 7 ) / 8 );
399 }
400
401 /**
402 * \brief Tell if a context can do the operation given by type
403 *
404 * \param ctx The context to query. It must have been initialized.
405 * \param type The desired type.
406 *
407 * \return 1 if the context can do operations on the given type.
408 * \return 0 if the context cannot do the operations on the given
409 * type. This is always the case for a context that has
410 * been initialized but not set up, or that has been
411 * cleared with mbedtls_pk_free().
412 */
413 int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type );
414
415 /**
416 * \brief Verify signature (including padding if relevant).
417 *
418 * \param ctx The PK context to use. It must have been set up.
419 * \param md_alg Hash algorithm used (see notes)
420 * \param hash Hash of the message to sign
421 * \param hash_len Hash length or 0 (see notes)
422 * \param sig Signature to verify
423 * \param sig_len Signature length
424 *
425 * \return 0 on success (signature is valid),
426 * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid
427 * signature in sig but its length is less than \p siglen,
428 * or a specific error code.
429 *
430 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
431 * Use \c mbedtls_pk_verify_ext( MBEDTLS_PK_RSASSA_PSS, ... )
432 * to verify RSASSA_PSS signatures.
433 *
434 * \note If hash_len is 0, then the length associated with md_alg
435 * is used instead, or an error returned if it is invalid.
436 *
437 * \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
438 */
439 int mbedtls_pk_verify( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
440 const unsigned char *hash, size_t hash_len,
441 const unsigned char *sig, size_t sig_len );
442
443 /**
444 * \brief Restartable version of \c mbedtls_pk_verify()
445 *
446 * \note Performs the same job as \c mbedtls_pk_verify(), but can
447 * return early and restart according to the limit set with
448 * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
449 * operations. For RSA, same as \c mbedtls_pk_verify().
450 *
451 * \param ctx The PK context to use. It must have been set up.
452 * \param md_alg Hash algorithm used (see notes)
453 * \param hash Hash of the message to sign
454 * \param hash_len Hash length or 0 (see notes)
455 * \param sig Signature to verify
456 * \param sig_len Signature length
457 * \param rs_ctx Restart context (NULL to disable restart)
458 *
459 * \return See \c mbedtls_pk_verify(), or
460 * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
461 * operations was reached: see \c mbedtls_ecp_set_max_ops().
462 */
463 int mbedtls_pk_verify_restartable( mbedtls_pk_context *ctx,
464 mbedtls_md_type_t md_alg,
465 const unsigned char *hash, size_t hash_len,
466 const unsigned char *sig, size_t sig_len,
467 mbedtls_pk_restart_ctx *rs_ctx );
468
469 /**
470 * \brief Verify signature, with options.
471 * (Includes verification of the padding depending on type.)
472 *
473 * \param type Signature type (inc. possible padding type) to verify
474 * \param options Pointer to type-specific options, or NULL
475 * \param ctx The PK context to use. It must have been set up.
476 * \param md_alg Hash algorithm used (see notes)
477 * \param hash Hash of the message to sign
478 * \param hash_len Hash length or 0 (see notes)
479 * \param sig Signature to verify
480 * \param sig_len Signature length
481 *
482 * \return 0 on success (signature is valid),
483 * #MBEDTLS_ERR_PK_TYPE_MISMATCH if the PK context can't be
484 * used for this type of signatures,
485 * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid
486 * signature in sig but its length is less than \p siglen,
487 * or a specific error code.
488 *
489 * \note If hash_len is 0, then the length associated with md_alg
490 * is used instead, or an error returned if it is invalid.
491 *
492 * \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
493 *
494 * \note If type is MBEDTLS_PK_RSASSA_PSS, then options must point
495 * to a mbedtls_pk_rsassa_pss_options structure,
496 * otherwise it must be NULL.
497 */
498 int mbedtls_pk_verify_ext( mbedtls_pk_type_t type, const void *options,
499 mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
500 const unsigned char *hash, size_t hash_len,
501 const unsigned char *sig, size_t sig_len );
502
503 /**
504 * \brief Make signature, including padding if relevant.
505 *
506 * \param ctx The PK context to use. It must have been set up
507 * with a private key.
508 * \param md_alg Hash algorithm used (see notes)
509 * \param hash Hash of the message to sign
510 * \param hash_len Hash length or 0 (see notes)
511 * \param sig Place to write the signature.
512 * It must have enough room for the signature.
513 * #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough.
514 * You may use a smaller buffer if it is large enough
515 * given the key type.
516 * \param sig_len On successful return,
517 * the number of bytes written to \p sig.
518 * \param f_rng RNG function
519 * \param p_rng RNG parameter
520 *
521 * \return 0 on success, or a specific error code.
522 *
523 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
524 * There is no interface in the PK module to make RSASSA-PSS
525 * signatures yet.
526 *
527 * \note If hash_len is 0, then the length associated with md_alg
528 * is used instead, or an error returned if it is invalid.
529 *
530 * \note For RSA, md_alg may be MBEDTLS_MD_NONE if hash_len != 0.
531 * For ECDSA, md_alg may never be MBEDTLS_MD_NONE.
532 */
533 int mbedtls_pk_sign( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
534 const unsigned char *hash, size_t hash_len,
535 unsigned char *sig, size_t *sig_len,
536 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
537
538 /**
539 * \brief Restartable version of \c mbedtls_pk_sign()
540 *
541 * \note Performs the same job as \c mbedtls_pk_sign(), but can
542 * return early and restart according to the limit set with
543 * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
544 * operations. For RSA, same as \c mbedtls_pk_sign().
545 *
546 * \param ctx The PK context to use. It must have been set up
547 * with a private key.
548 * \param md_alg Hash algorithm used (see notes for mbedtls_pk_sign())
549 * \param hash Hash of the message to sign
550 * \param hash_len Hash length or 0 (see notes for mbedtls_pk_sign())
551 * \param sig Place to write the signature.
552 * It must have enough room for the signature.
553 * #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough.
554 * You may use a smaller buffer if it is large enough
555 * given the key type.
556 * \param sig_len On successful return,
557 * the number of bytes written to \p sig.
558 * \param f_rng RNG function
559 * \param p_rng RNG parameter
560 * \param rs_ctx Restart context (NULL to disable restart)
561 *
562 * \return See \c mbedtls_pk_sign().
563 * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
564 * operations was reached: see \c mbedtls_ecp_set_max_ops().
565 */
566 int mbedtls_pk_sign_restartable( mbedtls_pk_context *ctx,
567 mbedtls_md_type_t md_alg,
568 const unsigned char *hash, size_t hash_len,
569 unsigned char *sig, size_t *sig_len,
570 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
571 mbedtls_pk_restart_ctx *rs_ctx );
572
573 /**
574 * \brief Decrypt message (including padding if relevant).
575 *
576 * \param ctx The PK context to use. It must have been set up
577 * with a private key.
578 * \param input Input to decrypt
579 * \param ilen Input size
580 * \param output Decrypted output
581 * \param olen Decrypted message length
582 * \param osize Size of the output buffer
583 * \param f_rng RNG function
584 * \param p_rng RNG parameter
585 *
586 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
587 *
588 * \return 0 on success, or a specific error code.
589 */
590 int mbedtls_pk_decrypt( mbedtls_pk_context *ctx,
591 const unsigned char *input, size_t ilen,
592 unsigned char *output, size_t *olen, size_t osize,
593 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
594
595 /**
596 * \brief Encrypt message (including padding if relevant).
597 *
598 * \param ctx The PK context to use. It must have been set up.
599 * \param input Message to encrypt
600 * \param ilen Message size
601 * \param output Encrypted output
602 * \param olen Encrypted output length
603 * \param osize Size of the output buffer
604 * \param f_rng RNG function
605 * \param p_rng RNG parameter
606 *
607 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
608 *
609 * \return 0 on success, or a specific error code.
610 */
611 int mbedtls_pk_encrypt( mbedtls_pk_context *ctx,
612 const unsigned char *input, size_t ilen,
613 unsigned char *output, size_t *olen, size_t osize,
614 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
615
616 /**
617 * \brief Check if a public-private pair of keys matches.
618 *
619 * \param pub Context holding a public key.
620 * \param prv Context holding a private (and public) key.
621 *
622 * \return \c 0 on success (keys were checked and match each other).
623 * \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the keys could not
624 * be checked - in that case they may or may not match.
625 * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA if a context is invalid.
626 * \return Another non-zero value if the keys do not match.
627 */
628 int mbedtls_pk_check_pair( const mbedtls_pk_context *pub, const mbedtls_pk_context *prv );
629
630 /**
631 * \brief Export debug information
632 *
633 * \param ctx The PK context to use. It must have been initialized.
634 * \param items Place to write debug items
635 *
636 * \return 0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
637 */
638 int mbedtls_pk_debug( const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items );
639
640 /**
641 * \brief Access the type name
642 *
643 * \param ctx The PK context to use. It must have been initialized.
644 *
645 * \return Type name on success, or "invalid PK"
646 */
647 const char * mbedtls_pk_get_name( const mbedtls_pk_context *ctx );
648
649 /**
650 * \brief Get the key type
651 *
652 * \param ctx The PK context to use. It must have been initialized.
653 *
654 * \return Type on success.
655 * \return #MBEDTLS_PK_NONE for a context that has not been set up.
656 */
657 mbedtls_pk_type_t mbedtls_pk_get_type( const mbedtls_pk_context *ctx );
658
659 #if defined(MBEDTLS_PK_PARSE_C)
660 /** \ingroup pk_module */
661 /**
662 * \brief Parse a private key in PEM or DER format
663 *
664 * \param ctx The PK context to fill. It must have been initialized
665 * but not set up.
666 * \param key Input buffer to parse.
667 * The buffer must contain the input exactly, with no
668 * extra trailing material. For PEM, the buffer must
669 * contain a null-terminated string.
670 * \param keylen Size of \b key in bytes.
671 * For PEM data, this includes the terminating null byte,
672 * so \p keylen must be equal to `strlen(key) + 1`.
673 * \param pwd Optional password for decryption.
674 * Pass \c NULL if expecting a non-encrypted key.
675 * Pass a string of \p pwdlen bytes if expecting an encrypted
676 * key; a non-encrypted key will also be accepted.
677 * The empty password is not supported.
678 * \param pwdlen Size of the password in bytes.
679 * Ignored if \p pwd is \c NULL.
680 *
681 * \note On entry, ctx must be empty, either freshly initialised
682 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
683 * specific key type, check the result with mbedtls_pk_can_do().
684 *
685 * \note The key is also checked for correctness.
686 *
687 * \return 0 if successful, or a specific PK or PEM error code
688 */
689 int mbedtls_pk_parse_key( mbedtls_pk_context *ctx,
690 const unsigned char *key, size_t keylen,
691 const unsigned char *pwd, size_t pwdlen );
692
693 /** \ingroup pk_module */
694 /**
695 * \brief Parse a public key in PEM or DER format
696 *
697 * \param ctx The PK context to fill. It must have been initialized
698 * but not set up.
699 * \param key Input buffer to parse.
700 * The buffer must contain the input exactly, with no
701 * extra trailing material. For PEM, the buffer must
702 * contain a null-terminated string.
703 * \param keylen Size of \b key in bytes.
704 * For PEM data, this includes the terminating null byte,
705 * so \p keylen must be equal to `strlen(key) + 1`.
706 *
707 * \note On entry, ctx must be empty, either freshly initialised
708 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
709 * specific key type, check the result with mbedtls_pk_can_do().
710 *
711 * \note The key is also checked for correctness.
712 *
713 * \return 0 if successful, or a specific PK or PEM error code
714 */
715 int mbedtls_pk_parse_public_key( mbedtls_pk_context *ctx,
716 const unsigned char *key, size_t keylen );
717
718 #if defined(MBEDTLS_FS_IO)
719 /** \ingroup pk_module */
720 /**
721 * \brief Load and parse a private key
722 *
723 * \param ctx The PK context to fill. It must have been initialized
724 * but not set up.
725 * \param path filename to read the private key from
726 * \param password Optional password to decrypt the file.
727 * Pass \c NULL if expecting a non-encrypted key.
728 * Pass a null-terminated string if expecting an encrypted
729 * key; a non-encrypted key will also be accepted.
730 * The empty password is not supported.
731 *
732 * \note On entry, ctx must be empty, either freshly initialised
733 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
734 * specific key type, check the result with mbedtls_pk_can_do().
735 *
736 * \note The key is also checked for correctness.
737 *
738 * \return 0 if successful, or a specific PK or PEM error code
739 */
740 int mbedtls_pk_parse_keyfile( mbedtls_pk_context *ctx,
741 const char *path, const char *password );
742
743 /** \ingroup pk_module */
744 /**
745 * \brief Load and parse a public key
746 *
747 * \param ctx The PK context to fill. It must have been initialized
748 * but not set up.
749 * \param path filename to read the public key from
750 *
751 * \note On entry, ctx must be empty, either freshly initialised
752 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If
753 * you need a specific key type, check the result with
754 * mbedtls_pk_can_do().
755 *
756 * \note The key is also checked for correctness.
757 *
758 * \return 0 if successful, or a specific PK or PEM error code
759 */
760 int mbedtls_pk_parse_public_keyfile( mbedtls_pk_context *ctx, const char *path );
761 #endif /* MBEDTLS_FS_IO */
762 #endif /* MBEDTLS_PK_PARSE_C */
763
764 #if defined(MBEDTLS_PK_WRITE_C)
765 /**
766 * \brief Write a private key to a PKCS#1 or SEC1 DER structure
767 * Note: data is written at the end of the buffer! Use the
768 * return value to determine where you should start
769 * using the buffer
770 *
771 * \param ctx PK context which must contain a valid private key.
772 * \param buf buffer to write to
773 * \param size size of the buffer
774 *
775 * \return length of data written if successful, or a specific
776 * error code
777 */
778 int mbedtls_pk_write_key_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
779
780 /**
781 * \brief Write a public key to a SubjectPublicKeyInfo DER structure
782 * Note: data is written at the end of the buffer! Use the
783 * return value to determine where you should start
784 * using the buffer
785 *
786 * \param ctx PK context which must contain a valid public or private key.
787 * \param buf buffer to write to
788 * \param size size of the buffer
789 *
790 * \return length of data written if successful, or a specific
791 * error code
792 */
793 int mbedtls_pk_write_pubkey_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
794
795 #if defined(MBEDTLS_PEM_WRITE_C)
796 /**
797 * \brief Write a public key to a PEM string
798 *
799 * \param ctx PK context which must contain a valid public or private key.
800 * \param buf Buffer to write to. The output includes a
801 * terminating null byte.
802 * \param size Size of the buffer in bytes.
803 *
804 * \return 0 if successful, or a specific error code
805 */
806 int mbedtls_pk_write_pubkey_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
807
808 /**
809 * \brief Write a private key to a PKCS#1 or SEC1 PEM string
810 *
811 * \param ctx PK context which must contain a valid private key.
812 * \param buf Buffer to write to. The output includes a
813 * terminating null byte.
814 * \param size Size of the buffer in bytes.
815 *
816 * \return 0 if successful, or a specific error code
817 */
818 int mbedtls_pk_write_key_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
819 #endif /* MBEDTLS_PEM_WRITE_C */
820 #endif /* MBEDTLS_PK_WRITE_C */
821
822 /*
823 * WARNING: Low-level functions. You probably do not want to use these unless
824 * you are certain you do ;)
825 */
826
827 #if defined(MBEDTLS_PK_PARSE_C)
828 /**
829 * \brief Parse a SubjectPublicKeyInfo DER structure
830 *
831 * \param p the position in the ASN.1 data
832 * \param end end of the buffer
833 * \param pk The PK context to fill. It must have been initialized
834 * but not set up.
835 *
836 * \return 0 if successful, or a specific PK error code
837 */
838 int mbedtls_pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
839 mbedtls_pk_context *pk );
840 #endif /* MBEDTLS_PK_PARSE_C */
841
842 #if defined(MBEDTLS_PK_WRITE_C)
843 /**
844 * \brief Write a subjectPublicKey to ASN.1 data
845 * Note: function works backwards in data buffer
846 *
847 * \param p reference to current position pointer
848 * \param start start of the buffer (for bounds-checking)
849 * \param key PK context which must contain a valid public or private key.
850 *
851 * \return the length written or a negative error code
852 */
853 int mbedtls_pk_write_pubkey( unsigned char **p, unsigned char *start,
854 const mbedtls_pk_context *key );
855 #endif /* MBEDTLS_PK_WRITE_C */
856
857 /*
858 * Internal module functions. You probably do not want to use these unless you
859 * know you do.
860 */
861 #if defined(MBEDTLS_FS_IO)
862 int mbedtls_pk_load_file( const char *path, unsigned char **buf, size_t *n );
863 #endif
864
865 #if defined(MBEDTLS_USE_PSA_CRYPTO)
866 /**
867 * \brief Turn an EC key into an opaque one.
868 *
869 * \warning This is a temporary utility function for tests. It might
870 * change or be removed at any time without notice.
871 *
872 * \note Only ECDSA keys are supported so far. Signing with the
873 * specified hash is the only allowed use of that key.
874 *
875 * \param pk Input: the EC key to import to a PSA key.
876 * Output: a PK context wrapping that PSA key.
877 * \param key Output: a PSA key identifier.
878 * It's the caller's responsibility to call
879 * psa_destroy_key() on that key identifier after calling
880 * mbedtls_pk_free() on the PK context.
881 * \param hash_alg The hash algorithm to allow for use with that key.
882 *
883 * \return \c 0 if successful.
884 * \return An Mbed TLS error code otherwise.
885 */
886 int mbedtls_pk_wrap_as_opaque( mbedtls_pk_context *pk,
887 psa_key_id_t *key,
888 psa_algorithm_t hash_alg );
889 #endif /* MBEDTLS_USE_PSA_CRYPTO */
890
891 #ifdef __cplusplus
892 }
893 #endif
894
895 #endif /* MBEDTLS_PK_H */
896
