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 #include "mbedtls/private_access.h"
26
27 #include "mbedtls/build_info.h"
28
29 #include "mbedtls/md.h"
30
31 #if defined(MBEDTLS_RSA_C)
32 #include "mbedtls/rsa.h"
33 #endif
34
35 #if defined(MBEDTLS_ECP_C)
36 #include "mbedtls/ecp.h"
37 #endif
38
39 #if defined(MBEDTLS_ECDSA_C)
40 #include "mbedtls/ecdsa.h"
41 #endif
42
43 #if defined(MBEDTLS_USE_PSA_CRYPTO)
44 #include "psa/crypto.h"
45 #endif
46
47 #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
48 !defined(inline) && !defined(__cplusplus)
49 #define inline __inline
50 #endif
51
52 /** Memory allocation failed. */
53 #define MBEDTLS_ERR_PK_ALLOC_FAILED -0x3F80
54 /** Type mismatch, eg attempt to encrypt with an ECDSA key */
55 #define MBEDTLS_ERR_PK_TYPE_MISMATCH -0x3F00
56 /** Bad input parameters to function. */
57 #define MBEDTLS_ERR_PK_BAD_INPUT_DATA -0x3E80
58 /** Read/write of file failed. */
59 #define MBEDTLS_ERR_PK_FILE_IO_ERROR -0x3E00
60 /** Unsupported key version */
61 #define MBEDTLS_ERR_PK_KEY_INVALID_VERSION -0x3D80
62 /** Invalid key tag or value. */
63 #define MBEDTLS_ERR_PK_KEY_INVALID_FORMAT -0x3D00
64 /** Key algorithm is unsupported (only RSA and EC are supported). */
65 #define MBEDTLS_ERR_PK_UNKNOWN_PK_ALG -0x3C80
66 /** Private key password can't be empty. */
67 #define MBEDTLS_ERR_PK_PASSWORD_REQUIRED -0x3C00
68 /** Given private key password does not allow for correct decryption. */
69 #define MBEDTLS_ERR_PK_PASSWORD_MISMATCH -0x3B80
70 /** The pubkey tag or value is invalid (only RSA and EC are supported). */
71 #define MBEDTLS_ERR_PK_INVALID_PUBKEY -0x3B00
72 /** The algorithm tag or value is invalid. */
73 #define MBEDTLS_ERR_PK_INVALID_ALG -0x3A80
74 /** Elliptic curve is unsupported (only NIST curves are supported). */
75 #define MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE -0x3A00
76 /** Unavailable feature, e.g. RSA disabled for RSA key. */
77 #define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE -0x3980
78 /** The buffer contains a valid signature followed by more data. */
79 #define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH -0x3900
80 /** The output buffer is too small. */
81 #define MBEDTLS_ERR_PK_BUFFER_TOO_SMALL -0x3880
82
83 #ifdef __cplusplus
84 extern "C" {
85 #endif
86
87 /**
88 * \brief Public key types
89 */
90 typedef enum {
91 MBEDTLS_PK_NONE=0,
92 MBEDTLS_PK_RSA,
93 MBEDTLS_PK_ECKEY,
94 MBEDTLS_PK_ECKEY_DH,
95 MBEDTLS_PK_ECDSA,
96 MBEDTLS_PK_RSA_ALT,
97 MBEDTLS_PK_RSASSA_PSS,
98 MBEDTLS_PK_OPAQUE,
99 } mbedtls_pk_type_t;
100
101 /**
102 * \brief Options for RSASSA-PSS signature verification.
103 * See \c mbedtls_rsa_rsassa_pss_verify_ext()
104 */
105 typedef struct mbedtls_pk_rsassa_pss_options
106 {
107 mbedtls_md_type_t MBEDTLS_PRIVATE(mgf1_hash_id);
108 int MBEDTLS_PRIVATE(expected_salt_len);
109
110 } mbedtls_pk_rsassa_pss_options;
111
112 /**
113 * \brief Maximum size of a signature made by mbedtls_pk_sign().
114 */
115 /* We need to set MBEDTLS_PK_SIGNATURE_MAX_SIZE to the maximum signature
116 * size among the supported signature types. Do it by starting at 0,
117 * then incrementally increasing to be large enough for each supported
118 * signature mechanism.
119 *
120 * The resulting value can be 0, for example if MBEDTLS_ECDH_C is enabled
121 * (which allows the pk module to be included) but neither MBEDTLS_ECDSA_C
122 * nor MBEDTLS_RSA_C nor any opaque signature mechanism (PSA or RSA_ALT).
123 */
124 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE 0
125
126 #if ( defined(MBEDTLS_RSA_C) || defined(MBEDTLS_PK_RSA_ALT_SUPPORT) ) && \
127 MBEDTLS_MPI_MAX_SIZE > MBEDTLS_PK_SIGNATURE_MAX_SIZE
128 /* For RSA, the signature can be as large as the bignum module allows.
129 * For RSA_ALT, the signature size is not necessarily tied to what the
130 * bignum module can do, but in the absence of any specific setting,
131 * we use that (rsa_alt_sign_wrap in library/pk_wrap.h will check). */
132 #undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
133 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE MBEDTLS_MPI_MAX_SIZE
134 #endif
135
136 #if defined(MBEDTLS_ECDSA_C) && \
137 MBEDTLS_ECDSA_MAX_LEN > MBEDTLS_PK_SIGNATURE_MAX_SIZE
138 /* For ECDSA, the ecdsa module exports a constant for the maximum
139 * signature size. */
140 #undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
141 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE MBEDTLS_ECDSA_MAX_LEN
142 #endif
143
144 #if defined(MBEDTLS_USE_PSA_CRYPTO)
145 #if PSA_SIGNATURE_MAX_SIZE > MBEDTLS_PK_SIGNATURE_MAX_SIZE
146 /* PSA_SIGNATURE_MAX_SIZE is the maximum size of a signature made
147 * through the PSA API in the PSA representation. */
148 #undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
149 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE PSA_SIGNATURE_MAX_SIZE
150 #endif
151
152 #if PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE + 11 > MBEDTLS_PK_SIGNATURE_MAX_SIZE
153 /* The Mbed TLS representation is different for ECDSA signatures:
154 * PSA uses the raw concatenation of r and s,
155 * whereas Mbed TLS uses the ASN.1 representation (SEQUENCE of two INTEGERs).
156 * Add the overhead of ASN.1: up to (1+2) + 2 * (1+2+1) for the
157 * types, lengths (represented by up to 2 bytes), and potential leading
158 * zeros of the INTEGERs and the SEQUENCE. */
159 #undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
160 #define MBEDTLS_PK_SIGNATURE_MAX_SIZE ( PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE + 11 )
161 #endif
162 #endif /* defined(MBEDTLS_USE_PSA_CRYPTO) */
163
164 /**
165 * \brief Types for interfacing with the debug module
166 */
167 typedef enum
168 {
169 MBEDTLS_PK_DEBUG_NONE = 0,
170 MBEDTLS_PK_DEBUG_MPI,
171 MBEDTLS_PK_DEBUG_ECP,
172 } mbedtls_pk_debug_type;
173
174 /**
175 * \brief Item to send to the debug module
176 */
177 typedef struct mbedtls_pk_debug_item
178 {
179 mbedtls_pk_debug_type MBEDTLS_PRIVATE(type);
180 const char *MBEDTLS_PRIVATE(name);
181 void *MBEDTLS_PRIVATE(value);
182 } mbedtls_pk_debug_item;
183
184 /** Maximum number of item send for debugging, plus 1 */
185 #define MBEDTLS_PK_DEBUG_MAX_ITEMS 3
186
187 /**
188 * \brief Public key information and operations
189 *
190 * \note The library does not support custom pk info structures,
191 * only built-in structures returned by
192 * mbedtls_cipher_info_from_type().
193 */
194 typedef struct mbedtls_pk_info_t mbedtls_pk_info_t;
195
196 /**
197 * \brief Public key container
198 */
199 typedef struct mbedtls_pk_context
200 {
201 const mbedtls_pk_info_t * MBEDTLS_PRIVATE(pk_info); /**< Public key information */
202 void * MBEDTLS_PRIVATE(pk_ctx); /**< Underlying public key context */
203 } mbedtls_pk_context;
204
205 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
206 /**
207 * \brief Context for resuming operations
208 */
209 typedef struct
210 {
211 const mbedtls_pk_info_t * MBEDTLS_PRIVATE(pk_info); /**< Public key information */
212 void * MBEDTLS_PRIVATE(rs_ctx); /**< Underlying restart context */
213 } mbedtls_pk_restart_ctx;
214 #else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
215 /* Now we can declare functions that take a pointer to that */
216 typedef void mbedtls_pk_restart_ctx;
217 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
218
219 #if defined(MBEDTLS_RSA_C)
220 /**
221 * Quick access to an RSA context inside a PK context.
222 *
223 * \warning You must make sure the PK context actually holds an RSA context
224 * before using this function!
225 */
mbedtls_pk_rsa(const mbedtls_pk_context pk)226 static inline mbedtls_rsa_context *mbedtls_pk_rsa( const mbedtls_pk_context pk )
227 {
228 return( (mbedtls_rsa_context *) (pk).MBEDTLS_PRIVATE(pk_ctx) );
229 }
230 #endif /* MBEDTLS_RSA_C */
231
232 #if defined(MBEDTLS_ECP_C)
233 /**
234 * Quick access to an EC context inside a PK context.
235 *
236 * \warning You must make sure the PK context actually holds an EC context
237 * before using this function!
238 */
mbedtls_pk_ec(const mbedtls_pk_context pk)239 static inline mbedtls_ecp_keypair *mbedtls_pk_ec( const mbedtls_pk_context pk )
240 {
241 return( (mbedtls_ecp_keypair *) (pk).MBEDTLS_PRIVATE(pk_ctx) );
242 }
243 #endif /* MBEDTLS_ECP_C */
244
245 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
246 /**
247 * \brief Types for RSA-alt abstraction
248 */
249 typedef int (*mbedtls_pk_rsa_alt_decrypt_func)( void *ctx, size_t *olen,
250 const unsigned char *input, unsigned char *output,
251 size_t output_max_len );
252 typedef int (*mbedtls_pk_rsa_alt_sign_func)( void *ctx,
253 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
254 mbedtls_md_type_t md_alg, unsigned int hashlen,
255 const unsigned char *hash, unsigned char *sig );
256 typedef size_t (*mbedtls_pk_rsa_alt_key_len_func)( void *ctx );
257 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
258
259 /**
260 * \brief Return information associated with the given PK type
261 *
262 * \param pk_type PK type to search for.
263 *
264 * \return The PK info associated with the type or NULL if not found.
265 */
266 const mbedtls_pk_info_t *mbedtls_pk_info_from_type( mbedtls_pk_type_t pk_type );
267
268 /**
269 * \brief Initialize a #mbedtls_pk_context (as NONE).
270 *
271 * \param ctx The context to initialize.
272 * This must not be \c NULL.
273 */
274 void mbedtls_pk_init( mbedtls_pk_context *ctx );
275
276 /**
277 * \brief Free the components of a #mbedtls_pk_context.
278 *
279 * \param ctx The context to clear. It must have been initialized.
280 * If this is \c NULL, this function does nothing.
281 *
282 * \note For contexts that have been set up with
283 * mbedtls_pk_setup_opaque(), this does not free the underlying
284 * PSA key and you still need to call psa_destroy_key()
285 * independently if you want to destroy that key.
286 */
287 void mbedtls_pk_free( mbedtls_pk_context *ctx );
288
289 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
290 /**
291 * \brief Initialize a restart context
292 *
293 * \param ctx The context to initialize.
294 * This must not be \c NULL.
295 */
296 void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx );
297
298 /**
299 * \brief Free the components of a restart context
300 *
301 * \param ctx The context to clear. It must have been initialized.
302 * If this is \c NULL, this function does nothing.
303 */
304 void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx );
305 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
306
307 /**
308 * \brief Initialize a PK context with the information given
309 * and allocates the type-specific PK subcontext.
310 *
311 * \param ctx Context to initialize. It must not have been set
312 * up yet (type #MBEDTLS_PK_NONE).
313 * \param info Information to use
314 *
315 * \return 0 on success,
316 * MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input,
317 * MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
318 *
319 * \note For contexts holding an RSA-alt key, use
320 * \c mbedtls_pk_setup_rsa_alt() instead.
321 */
322 int mbedtls_pk_setup( mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info );
323
324 #if defined(MBEDTLS_USE_PSA_CRYPTO)
325 /**
326 * \brief Initialize a PK context to wrap a PSA key.
327 *
328 * \note This function replaces mbedtls_pk_setup() for contexts
329 * that wrap a (possibly opaque) PSA key instead of
330 * storing and manipulating the key material directly.
331 *
332 * \param ctx The context to initialize. It must be empty (type NONE).
333 * \param key The PSA key to wrap, which must hold an ECC key pair
334 * (see notes below).
335 *
336 * \note The wrapped key must remain valid as long as the
337 * wrapping PK context is in use, that is at least between
338 * the point this function is called and the point
339 * mbedtls_pk_free() is called on this context. The wrapped
340 * key might then be independently used or destroyed.
341 *
342 * \note This function is currently only available for ECC key
343 * pairs (that is, ECC keys containing private key material).
344 * Support for other key types may be added later.
345 *
346 * \return \c 0 on success.
347 * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input
348 * (context already used, invalid key identifier).
349 * \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the key is not an
350 * ECC key pair.
351 * \return #MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
352 */
353 int mbedtls_pk_setup_opaque( mbedtls_pk_context *ctx,
354 const psa_key_id_t key );
355 #endif /* MBEDTLS_USE_PSA_CRYPTO */
356
357 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
358 /**
359 * \brief Initialize an RSA-alt context
360 *
361 * \param ctx Context to initialize. It must not have been set
362 * up yet (type #MBEDTLS_PK_NONE).
363 * \param key RSA key pointer
364 * \param decrypt_func Decryption function
365 * \param sign_func Signing function
366 * \param key_len_func Function returning key length in bytes
367 *
368 * \return 0 on success, or MBEDTLS_ERR_PK_BAD_INPUT_DATA if the
369 * context wasn't already initialized as RSA_ALT.
370 *
371 * \note This function replaces \c mbedtls_pk_setup() for RSA-alt.
372 */
373 int mbedtls_pk_setup_rsa_alt( mbedtls_pk_context *ctx, void * key,
374 mbedtls_pk_rsa_alt_decrypt_func decrypt_func,
375 mbedtls_pk_rsa_alt_sign_func sign_func,
376 mbedtls_pk_rsa_alt_key_len_func key_len_func );
377 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
378
379 /**
380 * \brief Get the size in bits of the underlying key
381 *
382 * \param ctx The context to query. It must have been initialized.
383 *
384 * \return Key size in bits, or 0 on error
385 */
386 size_t mbedtls_pk_get_bitlen( const mbedtls_pk_context *ctx );
387
388 /**
389 * \brief Get the length in bytes of the underlying key
390 *
391 * \param ctx The context to query. It must have been initialized.
392 *
393 * \return Key length in bytes, or 0 on error
394 */
mbedtls_pk_get_len(const mbedtls_pk_context * ctx)395 static inline size_t mbedtls_pk_get_len( const mbedtls_pk_context *ctx )
396 {
397 return( ( mbedtls_pk_get_bitlen( ctx ) + 7 ) / 8 );
398 }
399
400 /**
401 * \brief Tell if a context can do the operation given by type
402 *
403 * \param ctx The context to query. It must have been initialized.
404 * \param type The desired type.
405 *
406 * \return 1 if the context can do operations on the given type.
407 * \return 0 if the context cannot do the operations on the given
408 * type. This is always the case for a context that has
409 * been initialized but not set up, or that has been
410 * cleared with mbedtls_pk_free().
411 */
412 int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type );
413
414 /**
415 * \brief Verify signature (including padding if relevant).
416 *
417 * \param ctx The PK context to use. It must have been set up.
418 * \param md_alg Hash algorithm used.
419 * This can be #MBEDTLS_MD_NONE if the signature algorithm
420 * does not rely on a hash algorithm (non-deterministic
421 * ECDSA, RSA PKCS#1 v1.5).
422 * For PKCS#1 v1.5, if \p md_alg is #MBEDTLS_MD_NONE, then
423 * \p hash is the DigestInfo structure used by RFC 8017
424 * §9.2 steps 3–6. If \p md_alg is a valid hash
425 * algorithm then \p hash is the digest itself, and this
426 * function calculates the DigestInfo encoding internally.
427 * \param hash Hash of the message to sign
428 * \param hash_len Hash length
429 * \param sig Signature to verify
430 * \param sig_len Signature length
431 *
432 * \return 0 on success (signature is valid),
433 * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid
434 * signature in sig but its length is less than \p siglen,
435 * or a specific error code.
436 *
437 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
438 * Use \c mbedtls_pk_verify_ext( MBEDTLS_PK_RSASSA_PSS, ... )
439 * to verify RSASSA_PSS signatures.
440 */
441 int mbedtls_pk_verify( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
442 const unsigned char *hash, size_t hash_len,
443 const unsigned char *sig, size_t sig_len );
444
445 /**
446 * \brief Restartable version of \c mbedtls_pk_verify()
447 *
448 * \note Performs the same job as \c mbedtls_pk_verify(), but can
449 * return early and restart according to the limit set with
450 * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
451 * operations. For RSA, same as \c mbedtls_pk_verify().
452 *
453 * \param ctx The PK context to use. It must have been set up.
454 * \param md_alg Hash algorithm used (see notes)
455 * \param hash Hash of the message to sign
456 * \param hash_len Hash length or 0 (see notes)
457 * \param sig Signature to verify
458 * \param sig_len Signature length
459 * \param rs_ctx Restart context (NULL to disable restart)
460 *
461 * \return See \c mbedtls_pk_verify(), or
462 * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
463 * operations was reached: see \c mbedtls_ecp_set_max_ops().
464 */
465 int mbedtls_pk_verify_restartable( mbedtls_pk_context *ctx,
466 mbedtls_md_type_t md_alg,
467 const unsigned char *hash, size_t hash_len,
468 const unsigned char *sig, size_t sig_len,
469 mbedtls_pk_restart_ctx *rs_ctx );
470
471 /**
472 * \brief Verify signature, with options.
473 * (Includes verification of the padding depending on type.)
474 *
475 * \param type Signature type (inc. possible padding type) to verify
476 * \param options Pointer to type-specific options, or NULL
477 * \param ctx The PK context to use. It must have been set up.
478 * \param md_alg Hash algorithm used (see notes)
479 * \param hash Hash of the message to sign
480 * \param hash_len Hash length or 0 (see notes)
481 * \param sig Signature to verify
482 * \param sig_len Signature length
483 *
484 * \return 0 on success (signature is valid),
485 * #MBEDTLS_ERR_PK_TYPE_MISMATCH if the PK context can't be
486 * used for this type of signatures,
487 * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid
488 * signature in sig but its length is less than \p siglen,
489 * or a specific error code.
490 *
491 * \note If hash_len is 0, then the length associated with md_alg
492 * is used instead, or an error returned if it is invalid.
493 *
494 * \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
495 *
496 * \note If type is MBEDTLS_PK_RSASSA_PSS, then options must point
497 * to a mbedtls_pk_rsassa_pss_options structure,
498 * otherwise it must be NULL.
499 */
500 int mbedtls_pk_verify_ext( mbedtls_pk_type_t type, const void *options,
501 mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
502 const unsigned char *hash, size_t hash_len,
503 const unsigned char *sig, size_t sig_len );
504
505 /**
506 * \brief Make signature, including padding if relevant.
507 *
508 * \param ctx The PK context to use. It must have been set up
509 * with a private key.
510 * \param md_alg Hash algorithm used (see notes)
511 * \param hash Hash of the message to sign
512 * \param hash_len Hash length
513 * \param sig Place to write the signature.
514 * It must have enough room for the signature.
515 * #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough.
516 * You may use a smaller buffer if it is large enough
517 * given the key type.
518 * \param sig_size The size of the \p sig buffer in bytes.
519 * \param sig_len On successful return,
520 * the number of bytes written to \p sig.
521 * \param f_rng RNG function, must not be \c NULL.
522 * \param p_rng RNG parameter
523 *
524 * \return 0 on success, or a specific error code.
525 *
526 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
527 * There is no interface in the PK module to make RSASSA-PSS
528 * signatures yet.
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_size, 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
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_size The size of the \p sig buffer in bytes.
557 * \param sig_len On successful return,
558 * the number of bytes written to \p sig.
559 * \param f_rng RNG function, must not be \c NULL.
560 * \param p_rng RNG parameter
561 * \param rs_ctx Restart context (NULL to disable restart)
562 *
563 * \return See \c mbedtls_pk_sign().
564 * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
565 * operations was reached: see \c mbedtls_ecp_set_max_ops().
566 */
567 int mbedtls_pk_sign_restartable( mbedtls_pk_context *ctx,
568 mbedtls_md_type_t md_alg,
569 const unsigned char *hash, size_t hash_len,
570 unsigned char *sig, size_t sig_size, size_t *sig_len,
571 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
572 mbedtls_pk_restart_ctx *rs_ctx );
573
574 /**
575 * \brief Decrypt message (including padding if relevant).
576 *
577 * \param ctx The PK context to use. It must have been set up
578 * with a private key.
579 * \param input Input to decrypt
580 * \param ilen Input size
581 * \param output Decrypted output
582 * \param olen Decrypted message length
583 * \param osize Size of the output buffer
584 * \param f_rng RNG function, must not be \c NULL.
585 * \param p_rng RNG parameter
586 *
587 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
588 *
589 * \return 0 on success, or a specific error code.
590 */
591 int mbedtls_pk_decrypt( mbedtls_pk_context *ctx,
592 const unsigned char *input, size_t ilen,
593 unsigned char *output, size_t *olen, size_t osize,
594 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
595
596 /**
597 * \brief Encrypt message (including padding if relevant).
598 *
599 * \param ctx The PK context to use. It must have been set up.
600 * \param input Message to encrypt
601 * \param ilen Message size
602 * \param output Encrypted output
603 * \param olen Encrypted output length
604 * \param osize Size of the output buffer
605 * \param f_rng RNG function, must not be \c NULL.
606 * \param p_rng RNG parameter
607 *
608 * \note \p f_rng is used for padding generation.
609 *
610 * \note For RSA keys, the default padding type is PKCS#1 v1.5.
611 *
612 * \return 0 on success, or a specific error code.
613 */
614 int mbedtls_pk_encrypt( mbedtls_pk_context *ctx,
615 const unsigned char *input, size_t ilen,
616 unsigned char *output, size_t *olen, size_t osize,
617 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
618
619 /**
620 * \brief Check if a public-private pair of keys matches.
621 *
622 * \param pub Context holding a public key.
623 * \param prv Context holding a private (and public) key.
624 * \param f_rng RNG function, must not be \c NULL.
625 * \param p_rng RNG parameter
626 *
627 * \return \c 0 on success (keys were checked and match each other).
628 * \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the keys could not
629 * be checked - in that case they may or may not match.
630 * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA if a context is invalid.
631 * \return Another non-zero value if the keys do not match.
632 */
633 int mbedtls_pk_check_pair( const mbedtls_pk_context *pub,
634 const mbedtls_pk_context *prv,
635 int (*f_rng)(void *, unsigned char *, size_t),
636 void *p_rng );
637
638 /**
639 * \brief Export debug information
640 *
641 * \param ctx The PK context to use. It must have been initialized.
642 * \param items Place to write debug items
643 *
644 * \return 0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
645 */
646 int mbedtls_pk_debug( const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items );
647
648 /**
649 * \brief Access the type name
650 *
651 * \param ctx The PK context to use. It must have been initialized.
652 *
653 * \return Type name on success, or "invalid PK"
654 */
655 const char * mbedtls_pk_get_name( const mbedtls_pk_context *ctx );
656
657 /**
658 * \brief Get the key type
659 *
660 * \param ctx The PK context to use. It must have been initialized.
661 *
662 * \return Type on success.
663 * \return #MBEDTLS_PK_NONE for a context that has not been set up.
664 */
665 mbedtls_pk_type_t mbedtls_pk_get_type( const mbedtls_pk_context *ctx );
666
667 #if defined(MBEDTLS_PK_PARSE_C)
668 /** \ingroup pk_module */
669 /**
670 * \brief Parse a private key in PEM or DER format
671 *
672 * \param ctx The PK context to fill. It must have been initialized
673 * but not set up.
674 * \param key Input buffer to parse.
675 * The buffer must contain the input exactly, with no
676 * extra trailing material. For PEM, the buffer must
677 * contain a null-terminated string.
678 * \param keylen Size of \b key in bytes.
679 * For PEM data, this includes the terminating null byte,
680 * so \p keylen must be equal to `strlen(key) + 1`.
681 * \param pwd Optional password for decryption.
682 * Pass \c NULL if expecting a non-encrypted key.
683 * Pass a string of \p pwdlen bytes if expecting an encrypted
684 * key; a non-encrypted key will also be accepted.
685 * The empty password is not supported.
686 * \param pwdlen Size of the password in bytes.
687 * Ignored if \p pwd is \c NULL.
688 * \param f_rng RNG function, must not be \c NULL. Used for blinding.
689 * \param p_rng RNG parameter
690 *
691 * \note On entry, ctx must be empty, either freshly initialised
692 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
693 * specific key type, check the result with mbedtls_pk_can_do().
694 *
695 * \note The key is also checked for correctness.
696 *
697 * \return 0 if successful, or a specific PK or PEM error code
698 */
699 int mbedtls_pk_parse_key( mbedtls_pk_context *ctx,
700 const unsigned char *key, size_t keylen,
701 const unsigned char *pwd, size_t pwdlen,
702 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
703
704 /** \ingroup pk_module */
705 /**
706 * \brief Parse a public key in PEM or DER format
707 *
708 * \param ctx The PK context to fill. It must have been initialized
709 * but not set up.
710 * \param key Input buffer to parse.
711 * The buffer must contain the input exactly, with no
712 * extra trailing material. For PEM, the buffer must
713 * contain a null-terminated string.
714 * \param keylen Size of \b key in bytes.
715 * For PEM data, this includes the terminating null byte,
716 * so \p keylen must be equal to `strlen(key) + 1`.
717 *
718 * \note On entry, ctx must be empty, either freshly initialised
719 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
720 * specific key type, check the result with mbedtls_pk_can_do().
721 *
722 * \note The key is also checked for correctness.
723 *
724 * \return 0 if successful, or a specific PK or PEM error code
725 */
726 int mbedtls_pk_parse_public_key( mbedtls_pk_context *ctx,
727 const unsigned char *key, size_t keylen );
728
729 #if defined(MBEDTLS_FS_IO)
730 /** \ingroup pk_module */
731 /**
732 * \brief Load and parse a private key
733 *
734 * \param ctx The PK context to fill. It must have been initialized
735 * but not set up.
736 * \param path filename to read the private key from
737 * \param password Optional password to decrypt the file.
738 * Pass \c NULL if expecting a non-encrypted key.
739 * Pass a null-terminated string if expecting an encrypted
740 * key; a non-encrypted key will also be accepted.
741 * The empty password is not supported.
742 * \param f_rng RNG function, must not be \c NULL. Used for blinding.
743 * \param p_rng RNG parameter
744 *
745 * \note On entry, ctx must be empty, either freshly initialised
746 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
747 * specific key type, check the result with mbedtls_pk_can_do().
748 *
749 * \note The key is also checked for correctness.
750 *
751 * \return 0 if successful, or a specific PK or PEM error code
752 */
753 int mbedtls_pk_parse_keyfile( mbedtls_pk_context *ctx,
754 const char *path, const char *password,
755 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
756
757 /** \ingroup pk_module */
758 /**
759 * \brief Load and parse a public key
760 *
761 * \param ctx The PK context to fill. It must have been initialized
762 * but not set up.
763 * \param path filename to read the public key from
764 *
765 * \note On entry, ctx must be empty, either freshly initialised
766 * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If
767 * you need a specific key type, check the result with
768 * mbedtls_pk_can_do().
769 *
770 * \note The key is also checked for correctness.
771 *
772 * \return 0 if successful, or a specific PK or PEM error code
773 */
774 int mbedtls_pk_parse_public_keyfile( mbedtls_pk_context *ctx, const char *path );
775 #endif /* MBEDTLS_FS_IO */
776 #endif /* MBEDTLS_PK_PARSE_C */
777
778 #if defined(MBEDTLS_PK_WRITE_C)
779 /**
780 * \brief Write a private key to a PKCS#1 or SEC1 DER structure
781 * Note: data is written at the end of the buffer! Use the
782 * return value to determine where you should start
783 * using the buffer
784 *
785 * \param ctx PK context which must contain a valid private key.
786 * \param buf buffer to write to
787 * \param size size of the buffer
788 *
789 * \return length of data written if successful, or a specific
790 * error code
791 */
792 int mbedtls_pk_write_key_der( const mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
793
794 /**
795 * \brief Write a public key to a SubjectPublicKeyInfo DER structure
796 * Note: data is written at the end of the buffer! Use the
797 * return value to determine where you should start
798 * using the buffer
799 *
800 * \param ctx PK context which must contain a valid public or private key.
801 * \param buf buffer to write to
802 * \param size size of the buffer
803 *
804 * \return length of data written if successful, or a specific
805 * error code
806 */
807 int mbedtls_pk_write_pubkey_der( const mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
808
809 #if defined(MBEDTLS_PEM_WRITE_C)
810 /**
811 * \brief Write a public key to a PEM string
812 *
813 * \param ctx PK context which must contain a valid public or private key.
814 * \param buf Buffer to write to. The output includes a
815 * terminating null byte.
816 * \param size Size of the buffer in bytes.
817 *
818 * \return 0 if successful, or a specific error code
819 */
820 int mbedtls_pk_write_pubkey_pem( const mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
821
822 /**
823 * \brief Write a private key to a PKCS#1 or SEC1 PEM string
824 *
825 * \param ctx PK context which must contain a valid private key.
826 * \param buf Buffer to write to. The output includes a
827 * terminating null byte.
828 * \param size Size of the buffer in bytes.
829 *
830 * \return 0 if successful, or a specific error code
831 */
832 int mbedtls_pk_write_key_pem( const mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
833 #endif /* MBEDTLS_PEM_WRITE_C */
834 #endif /* MBEDTLS_PK_WRITE_C */
835
836 /*
837 * WARNING: Low-level functions. You probably do not want to use these unless
838 * you are certain you do ;)
839 */
840
841 #if defined(MBEDTLS_PK_PARSE_C)
842 /**
843 * \brief Parse a SubjectPublicKeyInfo DER structure
844 *
845 * \param p the position in the ASN.1 data
846 * \param end end of the buffer
847 * \param pk The PK context to fill. It must have been initialized
848 * but not set up.
849 *
850 * \return 0 if successful, or a specific PK error code
851 */
852 int mbedtls_pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
853 mbedtls_pk_context *pk );
854 #endif /* MBEDTLS_PK_PARSE_C */
855
856 #if defined(MBEDTLS_PK_WRITE_C)
857 /**
858 * \brief Write a subjectPublicKey to ASN.1 data
859 * Note: function works backwards in data buffer
860 *
861 * \param p reference to current position pointer
862 * \param start start of the buffer (for bounds-checking)
863 * \param key PK context which must contain a valid public or private key.
864 *
865 * \return the length written or a negative error code
866 */
867 int mbedtls_pk_write_pubkey( unsigned char **p, unsigned char *start,
868 const mbedtls_pk_context *key );
869 #endif /* MBEDTLS_PK_WRITE_C */
870
871 /*
872 * Internal module functions. You probably do not want to use these unless you
873 * know you do.
874 */
875 #if defined(MBEDTLS_FS_IO)
876 int mbedtls_pk_load_file( const char *path, unsigned char **buf, size_t *n );
877 #endif
878
879 #if defined(MBEDTLS_USE_PSA_CRYPTO)
880 /**
881 * \brief Turn an EC key into an opaque one.
882 *
883 * \warning This is a temporary utility function for tests. It might
884 * change or be removed at any time without notice.
885 *
886 * \note Only ECDSA keys are supported so far. Signing with the
887 * specified hash is the only allowed use of that key.
888 *
889 * \param pk Input: the EC key to import to a PSA key.
890 * Output: a PK context wrapping that PSA key.
891 * \param key Output: a PSA key identifier.
892 * It's the caller's responsibility to call
893 * psa_destroy_key() on that key identifier after calling
894 * mbedtls_pk_free() on the PK context.
895 * \param hash_alg The hash algorithm to allow for use with that key.
896 *
897 * \return \c 0 if successful.
898 * \return An Mbed TLS error code otherwise.
899 */
900 int mbedtls_pk_wrap_as_opaque( mbedtls_pk_context *pk,
901 psa_key_id_t *key,
902 psa_algorithm_t hash_alg );
903 #endif /* MBEDTLS_USE_PSA_CRYPTO */
904
905 #ifdef __cplusplus
906 }
907 #endif
908
909 #endif /* MBEDTLS_PK_H */
910