1 /**
2 * \file ssl.h
3 *
4 * \brief SSL/TLS functions.
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 #ifndef MBEDTLS_SSL_H
23 #define MBEDTLS_SSL_H
24 #include "mbedtls/platform_util.h"
25 #include "mbedtls/private_access.h"
26
27 #include "mbedtls/build_info.h"
28
29 #include "mbedtls/bignum.h"
30 #include "mbedtls/ecp.h"
31
32 #include "mbedtls/ssl_ciphersuites.h"
33
34 #if defined(MBEDTLS_X509_CRT_PARSE_C)
35 #include "mbedtls/x509_crt.h"
36 #include "mbedtls/x509_crl.h"
37 #endif
38
39 #if defined(MBEDTLS_DHM_C)
40 #include "mbedtls/dhm.h"
41 #endif
42
43 /* Adding guard for MBEDTLS_ECDSA_C to ensure no compile errors due
44 * to guards also being in ssl_srv.c and ssl_cli.c. There is a gap
45 * in functionality that access to ecdh_ctx structure is needed for
46 * MBEDTLS_ECDSA_C which does not seem correct.
47 */
48 #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C)
49 #include "mbedtls/ecdh.h"
50 #endif
51
52 #if defined(MBEDTLS_HAVE_TIME)
53 #include "mbedtls/platform_time.h"
54 #endif
55
56 #if defined(MBEDTLS_USE_PSA_CRYPTO)
57 #include "psa/crypto.h"
58 #endif /* MBEDTLS_USE_PSA_CRYPTO */
59
60 /*
61 * SSL Error codes
62 */
63 /** A cryptographic operation is in progress. Try again later. */
64 #define MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS -0x7000
65 /** The requested feature is not available. */
66 #define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE -0x7080
67 /** Bad input parameters to function. */
68 #define MBEDTLS_ERR_SSL_BAD_INPUT_DATA -0x7100
69 /** Verification of the message MAC failed. */
70 #define MBEDTLS_ERR_SSL_INVALID_MAC -0x7180
71 /** An invalid SSL record was received. */
72 #define MBEDTLS_ERR_SSL_INVALID_RECORD -0x7200
73 /** The connection indicated an EOF. */
74 #define MBEDTLS_ERR_SSL_CONN_EOF -0x7280
75 /** A message could not be parsed due to a syntactic error. */
76 #define MBEDTLS_ERR_SSL_DECODE_ERROR -0x7300
77 /* Error space gap */
78 /** No RNG was provided to the SSL module. */
79 #define MBEDTLS_ERR_SSL_NO_RNG -0x7400
80 /** No client certification received from the client, but required by the authentication mode. */
81 #define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE -0x7480
82 /** Client received an extended server hello containing an unsupported extension */
83 #define MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION -0x7500
84 /** No ALPN protocols supported that the client advertises */
85 #define MBEDTLS_ERR_SSL_NO_APPLICATION_PROTOCOL -0x7580
86 /** The own private key or pre-shared key is not set, but needed. */
87 #define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED -0x7600
88 /** No CA Chain is set, but required to operate. */
89 #define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED -0x7680
90 /** An unexpected message was received from our peer. */
91 #define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE -0x7700
92 /** A fatal alert message was received from our peer. */
93 #define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE -0x7780
94 /** No server could be identified matching the client's SNI. */
95 #define MBEDTLS_ERR_SSL_UNRECOGNIZED_NAME -0x7800
96 /** The peer notified us that the connection is going to be closed. */
97 #define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY -0x7880
98 /* Error space gap */
99 /* Error space gap */
100 /** Processing of the Certificate handshake message failed. */
101 #define MBEDTLS_ERR_SSL_BAD_CERTIFICATE -0x7A00
102 /* Error space gap */
103 /* Error space gap */
104 /* Error space gap */
105 /* Error space gap */
106 /* Error space gap */
107 /* Error space gap */
108 /* Error space gap */
109 /* Error space gap */
110 /* Error space gap */
111 /** Memory allocation failed */
112 #define MBEDTLS_ERR_SSL_ALLOC_FAILED -0x7F00
113 /** Hardware acceleration function returned with error */
114 #define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED -0x7F80
115 /** Hardware acceleration function skipped / left alone data */
116 #define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH -0x6F80
117 /** Handshake protocol not within min/max boundaries */
118 #define MBEDTLS_ERR_SSL_BAD_PROTOCOL_VERSION -0x6E80
119 /** The handshake negotiation failed. */
120 #define MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE -0x6E00
121 /** Session ticket has expired. */
122 #define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED -0x6D80
123 /** Public key type mismatch (eg, asked for RSA key exchange and presented EC key) */
124 #define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH -0x6D00
125 /** Unknown identity received (eg, PSK identity) */
126 #define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY -0x6C80
127 /** Internal error (eg, unexpected failure in lower-level module) */
128 #define MBEDTLS_ERR_SSL_INTERNAL_ERROR -0x6C00
129 /** A counter would wrap (eg, too many messages exchanged). */
130 #define MBEDTLS_ERR_SSL_COUNTER_WRAPPING -0x6B80
131 /** Unexpected message at ServerHello in renegotiation. */
132 #define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO -0x6B00
133 /** DTLS client must retry for hello verification */
134 #define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED -0x6A80
135 /** A buffer is too small to receive or write a message */
136 #define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL -0x6A00
137 /* Error space gap */
138 /** No data of requested type currently available on underlying transport. */
139 #define MBEDTLS_ERR_SSL_WANT_READ -0x6900
140 /** Connection requires a write call. */
141 #define MBEDTLS_ERR_SSL_WANT_WRITE -0x6880
142 /** The operation timed out. */
143 #define MBEDTLS_ERR_SSL_TIMEOUT -0x6800
144 /** The client initiated a reconnect from the same port. */
145 #define MBEDTLS_ERR_SSL_CLIENT_RECONNECT -0x6780
146 /** Record header looks valid but is not expected. */
147 #define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD -0x6700
148 /** The alert message received indicates a non-fatal error. */
149 #define MBEDTLS_ERR_SSL_NON_FATAL -0x6680
150 /** A field in a message was incorrect or inconsistent with other fields. */
151 #define MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER -0x6600
152 /** Internal-only message signaling that further message-processing should be done */
153 #define MBEDTLS_ERR_SSL_CONTINUE_PROCESSING -0x6580
154 /** The asynchronous operation is not completed yet. */
155 #define MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS -0x6500
156 /** Internal-only message signaling that a message arrived early. */
157 #define MBEDTLS_ERR_SSL_EARLY_MESSAGE -0x6480
158 /* Error space gap */
159 /* Error space gap */
160 /* Error space gap */
161 /* Error space gap */
162 /* Error space gap */
163 /* Error space gap */
164 /* Error space gap */
165 /* Error space gap */
166 /** An encrypted DTLS-frame with an unexpected CID was received. */
167 #define MBEDTLS_ERR_SSL_UNEXPECTED_CID -0x6000
168 /** An operation failed due to an unexpected version or configuration. */
169 #define MBEDTLS_ERR_SSL_VERSION_MISMATCH -0x5F00
170 /** Invalid value in SSL config */
171 #define MBEDTLS_ERR_SSL_BAD_CONFIG -0x5E80
172
173 /*
174 * TLS 1.3 NamedGroup values
175 *
176 * From RF 8446
177 * enum {
178 * // Elliptic Curve Groups (ECDHE)
179 * secp256r1(0x0017), secp384r1(0x0018), secp521r1(0x0019),
180 * x25519(0x001D), x448(0x001E),
181 * // Finite Field Groups (DHE)
182 * ffdhe2048(0x0100), ffdhe3072(0x0101), ffdhe4096(0x0102),
183 * ffdhe6144(0x0103), ffdhe8192(0x0104),
184 * // Reserved Code Points
185 * ffdhe_private_use(0x01FC..0x01FF),
186 * ecdhe_private_use(0xFE00..0xFEFF),
187 * (0xFFFF)
188 * } NamedGroup;
189 *
190 */
191
192 /* Elliptic Curve Groups (ECDHE) */
193 #define MBEDTLS_SSL_IANA_TLS_GROUP_NONE 0
194 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP192K1 0x0012
195 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP192R1 0x0013
196 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP224K1 0x0014
197 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP224R1 0x0015
198 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP256K1 0x0016
199 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP256R1 0x0017
200 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP384R1 0x0018
201 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP521R1 0x0019
202 #define MBEDTLS_SSL_IANA_TLS_GROUP_BP256R1 0x001A
203 #define MBEDTLS_SSL_IANA_TLS_GROUP_BP384R1 0x001B
204 #define MBEDTLS_SSL_IANA_TLS_GROUP_BP512R1 0x001C
205 #define MBEDTLS_SSL_IANA_TLS_GROUP_X25519 0x001D
206 #define MBEDTLS_SSL_IANA_TLS_GROUP_X448 0x001E
207 /* Finite Field Groups (DHE) */
208 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE2048 0x0100
209 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE3072 0x0101
210 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE4096 0x0102
211 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE6144 0x0103
212 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE8192 0x0104
213
214 /*
215 * TLS 1.3 Key Exchange Modes
216 *
217 * Mbed TLS internal identifiers for use with the SSL configuration API
218 * mbedtls_ssl_conf_tls13_key_exchange_modes().
219 */
220
221 #define MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK ( 1u << 0 ) /*!< Pure-PSK TLS 1.3 key exchange,
222 * encompassing both externally agreed PSKs
223 * as well as resumption PSKs. */
224 #define MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL ( 1u << 1 ) /*!< Pure-Ephemeral TLS 1.3 key exchanges,
225 * including for example ECDHE and DHE
226 * key exchanges. */
227 #define MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_EPHEMERAL ( 1u << 2 ) /*!< PSK-Ephemeral TLS 1.3 key exchanges,
228 * using both a PSK and an ephemeral
229 * key exchange. */
230
231 /* Convenience macros for sets of key exchanges. */
232 #define MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_ALL \
233 ( MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK | \
234 MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_EPHEMERAL | \
235 MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL ) /*!< All TLS 1.3 key exchanges */
236 #define MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_ALL \
237 ( MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK | \
238 MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_EPHEMERAL ) /*!< All PSK-based TLS 1.3 key exchanges */
239 #define MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL_ALL \
240 ( MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL | \
241 MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_EPHEMERAL ) /*!< All ephemeral TLS 1.3 key exchanges */
242
243 /*
244 * Various constants
245 */
246
247 /* These are the high an low bytes of ProtocolVersion as defined by:
248 * - RFC 5246: ProtocolVersion version = { 3, 3 }; // TLS v1.2
249 * - RFC 8446: see section 4.2.1
250 */
251 #define MBEDTLS_SSL_MAJOR_VERSION_3 3
252 #define MBEDTLS_SSL_MINOR_VERSION_3 3 /*!< TLS v1.2 */
253 #define MBEDTLS_SSL_MINOR_VERSION_4 4 /*!< TLS v1.3 (experimental) */
254
255 #define MBEDTLS_SSL_TRANSPORT_STREAM 0 /*!< TLS */
256 #define MBEDTLS_SSL_TRANSPORT_DATAGRAM 1 /*!< DTLS */
257
258 #define MBEDTLS_SSL_MAX_HOST_NAME_LEN 255 /*!< Maximum host name defined in RFC 1035 */
259 #define MBEDTLS_SSL_MAX_ALPN_NAME_LEN 255 /*!< Maximum size in bytes of a protocol name in alpn ext., RFC 7301 */
260
261 #define MBEDTLS_SSL_MAX_ALPN_LIST_LEN 65535 /*!< Maximum size in bytes of list in alpn ext., RFC 7301 */
262
263 /* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
264 * NONE must be zero so that memset()ing structure to zero works */
265 #define MBEDTLS_SSL_MAX_FRAG_LEN_NONE 0 /*!< don't use this extension */
266 #define MBEDTLS_SSL_MAX_FRAG_LEN_512 1 /*!< MaxFragmentLength 2^9 */
267 #define MBEDTLS_SSL_MAX_FRAG_LEN_1024 2 /*!< MaxFragmentLength 2^10 */
268 #define MBEDTLS_SSL_MAX_FRAG_LEN_2048 3 /*!< MaxFragmentLength 2^11 */
269 #define MBEDTLS_SSL_MAX_FRAG_LEN_4096 4 /*!< MaxFragmentLength 2^12 */
270 #define MBEDTLS_SSL_MAX_FRAG_LEN_INVALID 5 /*!< first invalid value */
271
272 #define MBEDTLS_SSL_IS_CLIENT 0
273 #define MBEDTLS_SSL_IS_SERVER 1
274
275 #define MBEDTLS_SSL_EXTENDED_MS_DISABLED 0
276 #define MBEDTLS_SSL_EXTENDED_MS_ENABLED 1
277
278 #define MBEDTLS_SSL_CID_DISABLED 0
279 #define MBEDTLS_SSL_CID_ENABLED 1
280
281 #define MBEDTLS_SSL_ETM_DISABLED 0
282 #define MBEDTLS_SSL_ETM_ENABLED 1
283
284 #define MBEDTLS_SSL_COMPRESS_NULL 0
285
286 #define MBEDTLS_SSL_VERIFY_NONE 0
287 #define MBEDTLS_SSL_VERIFY_OPTIONAL 1
288 #define MBEDTLS_SSL_VERIFY_REQUIRED 2
289 #define MBEDTLS_SSL_VERIFY_UNSET 3 /* Used only for sni_authmode */
290
291 #define MBEDTLS_SSL_LEGACY_RENEGOTIATION 0
292 #define MBEDTLS_SSL_SECURE_RENEGOTIATION 1
293
294 #define MBEDTLS_SSL_RENEGOTIATION_DISABLED 0
295 #define MBEDTLS_SSL_RENEGOTIATION_ENABLED 1
296
297 #define MBEDTLS_SSL_ANTI_REPLAY_DISABLED 0
298 #define MBEDTLS_SSL_ANTI_REPLAY_ENABLED 1
299
300 #define MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED -1
301 #define MBEDTLS_SSL_RENEGO_MAX_RECORDS_DEFAULT 16
302
303 #define MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION 0
304 #define MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION 1
305 #define MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE 2
306
307 #define MBEDTLS_SSL_TRUNC_HMAC_DISABLED 0
308 #define MBEDTLS_SSL_TRUNC_HMAC_ENABLED 1
309 #define MBEDTLS_SSL_TRUNCATED_HMAC_LEN 10 /* 80 bits, rfc 6066 section 7 */
310
311 #define MBEDTLS_SSL_SESSION_TICKETS_DISABLED 0
312 #define MBEDTLS_SSL_SESSION_TICKETS_ENABLED 1
313
314 #define MBEDTLS_SSL_PRESET_DEFAULT 0
315 #define MBEDTLS_SSL_PRESET_SUITEB 2
316
317 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED 1
318 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 0
319
320 #define MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED 0
321 #define MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED 1
322
323 #define MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_CLIENT 1
324 #define MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER 0
325
326 /*
327 * Default range for DTLS retransmission timer value, in milliseconds.
328 * RFC 6347 4.2.4.1 says from 1 second to 60 seconds.
329 */
330 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN 1000
331 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX 60000
332
333 /**
334 * \name SECTION: Module settings
335 *
336 * The configuration options you can set for this module are in this section.
337 * Either change them in mbedtls_config.h or define them on the compiler command line.
338 * \{
339 */
340
341 /*
342 * Maximum fragment length in bytes,
343 * determines the size of each of the two internal I/O buffers.
344 *
345 * Note: the RFC defines the default size of SSL / TLS messages. If you
346 * change the value here, other clients / servers may not be able to
347 * communicate with you anymore. Only change this value if you control
348 * both sides of the connection and have it reduced at both sides, or
349 * if you're using the Max Fragment Length extension and you know all your
350 * peers are using it too!
351 */
352 #if !defined(MBEDTLS_SSL_IN_CONTENT_LEN)
353 #define MBEDTLS_SSL_IN_CONTENT_LEN 16384
354 #endif
355
356 #if !defined(MBEDTLS_SSL_OUT_CONTENT_LEN)
357 #define MBEDTLS_SSL_OUT_CONTENT_LEN 16384
358 #endif
359
360 /*
361 * Maximum number of heap-allocated bytes for the purpose of
362 * DTLS handshake message reassembly and future message buffering.
363 */
364 #if !defined(MBEDTLS_SSL_DTLS_MAX_BUFFERING)
365 #define MBEDTLS_SSL_DTLS_MAX_BUFFERING 32768
366 #endif
367
368 /*
369 * Maximum length of CIDs for incoming and outgoing messages.
370 */
371 #if !defined(MBEDTLS_SSL_CID_IN_LEN_MAX)
372 #define MBEDTLS_SSL_CID_IN_LEN_MAX 32
373 #endif
374
375 #if !defined(MBEDTLS_SSL_CID_OUT_LEN_MAX)
376 #define MBEDTLS_SSL_CID_OUT_LEN_MAX 32
377 #endif
378
379 #if !defined(MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY)
380 #define MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 16
381 #endif
382
383 /* \} name SECTION: Module settings */
384
385 /*
386 * Length of the verify data for secure renegotiation
387 */
388 #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 12
389
390 /*
391 * Signaling ciphersuite values (SCSV)
392 */
393 #define MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO 0xFF /**< renegotiation info ext */
394
395 /*
396 * Supported Signature and Hash algorithms (For TLS 1.2)
397 * RFC 5246 section 7.4.1.4.1
398 */
399 #define MBEDTLS_SSL_HASH_NONE 0
400 #define MBEDTLS_SSL_HASH_MD5 1
401 #define MBEDTLS_SSL_HASH_SHA1 2
402 #define MBEDTLS_SSL_HASH_SHA224 3
403 #define MBEDTLS_SSL_HASH_SHA256 4
404 #define MBEDTLS_SSL_HASH_SHA384 5
405 #define MBEDTLS_SSL_HASH_SHA512 6
406
407 #define MBEDTLS_SSL_SIG_ANON 0
408 #define MBEDTLS_SSL_SIG_RSA 1
409 #define MBEDTLS_SSL_SIG_ECDSA 3
410
411 /*
412 * TLS 1.3 signature algorithms
413 * RFC 8446, Section 4.2.2
414 */
415
416 /* RSASSA-PKCS1-v1_5 algorithms */
417 #define MBEDTLS_TLS13_SIG_RSA_PKCS1_SHA256 0x0401
418 #define MBEDTLS_TLS13_SIG_RSA_PKCS1_SHA384 0x0501
419 #define MBEDTLS_TLS13_SIG_RSA_PKCS1_SHA512 0x0601
420
421 /* ECDSA algorithms */
422 #define MBEDTLS_TLS13_SIG_ECDSA_SECP256R1_SHA256 0x0403
423 #define MBEDTLS_TLS13_SIG_ECDSA_SECP384R1_SHA384 0x0503
424 #define MBEDTLS_TLS13_SIG_ECDSA_SECP521R1_SHA512 0x0603
425
426 /* RSASSA-PSS algorithms with public key OID rsaEncryption */
427 #define MBEDTLS_TLS13_SIG_RSA_PSS_RSAE_SHA256 0x0804
428 #define MBEDTLS_TLS13_SIG_RSA_PSS_RSAE_SHA384 0x0805
429 #define MBEDTLS_TLS13_SIG_RSA_PSS_RSAE_SHA512 0x0806
430
431 /* EdDSA algorithms */
432 #define MBEDTLS_TLS13_SIG_ED25519 0x0807
433 #define MBEDTLS_TLS13_SIG_ED448 0x0808
434
435 /* RSASSA-PSS algorithms with public key OID RSASSA-PSS */
436 #define MBEDTLS_TLS13_SIG_RSA_PSS_PSS_SHA256 0x0809
437 #define MBEDTLS_TLS13_SIG_RSA_PSS_PSS_SHA384 0x080A
438 #define MBEDTLS_TLS13_SIG_RSA_PSS_PSS_SHA512 0x080B
439
440 /* LEGACY ALGORITHMS */
441 #define MBEDTLS_TLS13_SIG_RSA_PKCS1_SHA1 0x0201
442 #define MBEDTLS_TLS13_SIG_ECDSA_SHA1 0x0203
443
444 #define MBEDTLS_TLS13_SIG_NONE 0x0
445
446 /*
447 * Client Certificate Types
448 * RFC 5246 section 7.4.4 plus RFC 4492 section 5.5
449 */
450 #define MBEDTLS_SSL_CERT_TYPE_RSA_SIGN 1
451 #define MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN 64
452
453 /*
454 * Message, alert and handshake types
455 */
456 #define MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC 20
457 #define MBEDTLS_SSL_MSG_ALERT 21
458 #define MBEDTLS_SSL_MSG_HANDSHAKE 22
459 #define MBEDTLS_SSL_MSG_APPLICATION_DATA 23
460 #define MBEDTLS_SSL_MSG_CID 25
461
462 #define MBEDTLS_SSL_ALERT_LEVEL_WARNING 1
463 #define MBEDTLS_SSL_ALERT_LEVEL_FATAL 2
464
465 #define MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY 0 /* 0x00 */
466 #define MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE 10 /* 0x0A */
467 #define MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC 20 /* 0x14 */
468 #define MBEDTLS_SSL_ALERT_MSG_DECRYPTION_FAILED 21 /* 0x15 */
469 #define MBEDTLS_SSL_ALERT_MSG_RECORD_OVERFLOW 22 /* 0x16 */
470 #define MBEDTLS_SSL_ALERT_MSG_DECOMPRESSION_FAILURE 30 /* 0x1E */
471 #define MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE 40 /* 0x28 */
472 #define MBEDTLS_SSL_ALERT_MSG_NO_CERT 41 /* 0x29 */
473 #define MBEDTLS_SSL_ALERT_MSG_BAD_CERT 42 /* 0x2A */
474 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT 43 /* 0x2B */
475 #define MBEDTLS_SSL_ALERT_MSG_CERT_REVOKED 44 /* 0x2C */
476 #define MBEDTLS_SSL_ALERT_MSG_CERT_EXPIRED 45 /* 0x2D */
477 #define MBEDTLS_SSL_ALERT_MSG_CERT_UNKNOWN 46 /* 0x2E */
478 #define MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER 47 /* 0x2F */
479 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_CA 48 /* 0x30 */
480 #define MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED 49 /* 0x31 */
481 #define MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR 50 /* 0x32 */
482 #define MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR 51 /* 0x33 */
483 #define MBEDTLS_SSL_ALERT_MSG_EXPORT_RESTRICTION 60 /* 0x3C */
484 #define MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION 70 /* 0x46 */
485 #define MBEDTLS_SSL_ALERT_MSG_INSUFFICIENT_SECURITY 71 /* 0x47 */
486 #define MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR 80 /* 0x50 */
487 #define MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK 86 /* 0x56 */
488 #define MBEDTLS_SSL_ALERT_MSG_USER_CANCELED 90 /* 0x5A */
489 #define MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION 100 /* 0x64 */
490 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT 110 /* 0x6E */
491 #define MBEDTLS_SSL_ALERT_MSG_UNRECOGNIZED_NAME 112 /* 0x70 */
492 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY 115 /* 0x73 */
493 #define MBEDTLS_SSL_ALERT_MSG_NO_APPLICATION_PROTOCOL 120 /* 0x78 */
494
495 #define MBEDTLS_SSL_HS_HELLO_REQUEST 0
496 #define MBEDTLS_SSL_HS_CLIENT_HELLO 1
497 #define MBEDTLS_SSL_HS_SERVER_HELLO 2
498 #define MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST 3
499 #define MBEDTLS_SSL_HS_NEW_SESSION_TICKET 4
500 #define MBEDTLS_SSL_HS_ENCRYPTED_EXTENSIONS 8 // NEW IN TLS 1.3
501 #define MBEDTLS_SSL_HS_CERTIFICATE 11
502 #define MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE 12
503 #define MBEDTLS_SSL_HS_CERTIFICATE_REQUEST 13
504 #define MBEDTLS_SSL_HS_SERVER_HELLO_DONE 14
505 #define MBEDTLS_SSL_HS_CERTIFICATE_VERIFY 15
506 #define MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE 16
507 #define MBEDTLS_SSL_HS_FINISHED 20
508
509 /*
510 * TLS extensions
511 */
512 #define MBEDTLS_TLS_EXT_SERVERNAME 0
513 #define MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME 0
514
515 #define MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH 1
516
517 #define MBEDTLS_TLS_EXT_TRUNCATED_HMAC 4
518 #define MBEDTLS_TLS_EXT_STATUS_REQUEST 5 /* RFC 6066 TLS 1.2 and 1.3 */
519
520 #define MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES 10
521 #define MBEDTLS_TLS_EXT_SUPPORTED_GROUPS 10 /* RFC 8422,7919 TLS 1.2 and 1.3 */
522 #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS 11
523
524 #define MBEDTLS_TLS_EXT_SIG_ALG 13 /* RFC 8446 TLS 1.3 */
525 #define MBEDTLS_TLS_EXT_USE_SRTP 14
526 #define MBEDTLS_TLS_EXT_HEARTBEAT 15 /* RFC 6520 TLS 1.2 and 1.3 */
527 #define MBEDTLS_TLS_EXT_ALPN 16
528
529 #define MBEDTLS_TLS_EXT_SCT 18 /* RFC 6962 TLS 1.2 and 1.3 */
530 #define MBEDTLS_TLS_EXT_CLI_CERT_TYPE 19 /* RFC 7250 TLS 1.2 and 1.3 */
531 #define MBEDTLS_TLS_EXT_SERV_CERT_TYPE 20 /* RFC 7250 TLS 1.2 and 1.3 */
532 #define MBEDTLS_TLS_EXT_PADDING 21 /* RFC 7685 TLS 1.2 and 1.3 */
533 #define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC 22 /* 0x16 */
534 #define MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET 0x0017 /* 23 */
535
536 #define MBEDTLS_TLS_EXT_SESSION_TICKET 35
537
538 #define MBEDTLS_TLS_EXT_PRE_SHARED_KEY 41 /* RFC 8446 TLS 1.3 */
539 #define MBEDTLS_TLS_EXT_EARLY_DATA 42 /* RFC 8446 TLS 1.3 */
540 #define MBEDTLS_TLS_EXT_SUPPORTED_VERSIONS 43 /* RFC 8446 TLS 1.3 */
541 #define MBEDTLS_TLS_EXT_COOKIE 44 /* RFC 8446 TLS 1.3 */
542 #define MBEDTLS_TLS_EXT_PSK_KEY_EXCHANGE_MODES 45 /* RFC 8446 TLS 1.3 */
543
544 #define MBEDTLS_TLS_EXT_CERT_AUTH 47 /* RFC 8446 TLS 1.3 */
545 #define MBEDTLS_TLS_EXT_OID_FILTERS 48 /* RFC 8446 TLS 1.3 */
546 #define MBEDTLS_TLS_EXT_POST_HANDSHAKE_AUTH 49 /* RFC 8446 TLS 1.3 */
547 #define MBEDTLS_TLS_EXT_SIG_ALG_CERT 50 /* RFC 8446 TLS 1.3 */
548 #define MBEDTLS_TLS_EXT_KEY_SHARE 51 /* RFC 8446 TLS 1.3 */
549
550 /* The value of the CID extension is still TBD as of
551 * draft-ietf-tls-dtls-connection-id-05
552 * (https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05).
553 *
554 * A future minor revision of Mbed TLS may change the default value of
555 * this option to match evolving standards and usage.
556 */
557 #if !defined(MBEDTLS_TLS_EXT_CID)
558 #define MBEDTLS_TLS_EXT_CID 254 /* TBD */
559 #endif
560
561 #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP 256 /* experimental */
562
563 #define MBEDTLS_TLS_EXT_RENEGOTIATION_INFO 0xFF01
564
565 /*
566 * Size defines
567 */
568 #if !defined(MBEDTLS_PSK_MAX_LEN)
569 #define MBEDTLS_PSK_MAX_LEN 32 /* 256 bits */
570 #endif
571
572 /* Dummy type used only for its size */
573 union mbedtls_ssl_premaster_secret
574 {
575 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
576 unsigned char _pms_rsa[48]; /* RFC 5246 8.1.1 */
577 #endif
578 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)
579 unsigned char _pms_dhm[MBEDTLS_MPI_MAX_SIZE]; /* RFC 5246 8.1.2 */
580 #endif
581 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
582 defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
583 defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
584 defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
585 unsigned char _pms_ecdh[MBEDTLS_ECP_MAX_BYTES]; /* RFC 4492 5.10 */
586 #endif
587 #if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
588 unsigned char _pms_psk[4 + 2 * MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 2 */
589 #endif
590 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
591 unsigned char _pms_dhe_psk[4 + MBEDTLS_MPI_MAX_SIZE
592 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 3 */
593 #endif
594 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
595 unsigned char _pms_rsa_psk[52 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 4 */
596 #endif
597 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
598 unsigned char _pms_ecdhe_psk[4 + MBEDTLS_ECP_MAX_BYTES
599 + MBEDTLS_PSK_MAX_LEN]; /* RFC 5489 2 */
600 #endif
601 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
602 unsigned char _pms_ecjpake[32]; /* Thread spec: SHA-256 output */
603 #endif
604 };
605
606 #define MBEDTLS_PREMASTER_SIZE sizeof( union mbedtls_ssl_premaster_secret )
607
608 #define MBEDTLS_TLS1_3_MD_MAX_SIZE MBEDTLS_MD_MAX_SIZE
609
610 /* Length in number of bytes of the TLS sequence number */
611 #define MBEDTLS_SSL_SEQUENCE_NUMBER_LEN 8
612
613 #ifdef __cplusplus
614 extern "C" {
615 #endif
616
617 /*
618 * SSL state machine
619 */
620 typedef enum
621 {
622 MBEDTLS_SSL_HELLO_REQUEST,
623 MBEDTLS_SSL_CLIENT_HELLO,
624 MBEDTLS_SSL_SERVER_HELLO,
625 MBEDTLS_SSL_SERVER_CERTIFICATE,
626 MBEDTLS_SSL_SERVER_KEY_EXCHANGE,
627 MBEDTLS_SSL_CERTIFICATE_REQUEST,
628 MBEDTLS_SSL_SERVER_HELLO_DONE,
629 MBEDTLS_SSL_CLIENT_CERTIFICATE,
630 MBEDTLS_SSL_CLIENT_KEY_EXCHANGE,
631 MBEDTLS_SSL_CERTIFICATE_VERIFY,
632 MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC,
633 MBEDTLS_SSL_CLIENT_FINISHED,
634 MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC,
635 MBEDTLS_SSL_SERVER_FINISHED,
636 MBEDTLS_SSL_FLUSH_BUFFERS,
637 MBEDTLS_SSL_HANDSHAKE_WRAPUP,
638 MBEDTLS_SSL_HANDSHAKE_OVER,
639 MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET,
640 MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT,
641 #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
642 MBEDTLS_SSL_ENCRYPTED_EXTENSIONS,
643 MBEDTLS_SSL_CLIENT_CERTIFICATE_VERIFY,
644 #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
645 }
646 mbedtls_ssl_states;
647
648 /**
649 * \brief Callback type: send data on the network.
650 *
651 * \note That callback may be either blocking or non-blocking.
652 *
653 * \param ctx Context for the send callback (typically a file descriptor)
654 * \param buf Buffer holding the data to send
655 * \param len Length of the data to send
656 *
657 * \return The callback must return the number of bytes sent if any,
658 * or a non-zero error code.
659 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_WRITE
660 * must be returned when the operation would block.
661 *
662 * \note The callback is allowed to send fewer bytes than requested.
663 * It must always return the number of bytes actually sent.
664 */
665 typedef int mbedtls_ssl_send_t( void *ctx,
666 const unsigned char *buf,
667 size_t len );
668
669 /**
670 * \brief Callback type: receive data from the network.
671 *
672 * \note That callback may be either blocking or non-blocking.
673 *
674 * \param ctx Context for the receive callback (typically a file
675 * descriptor)
676 * \param buf Buffer to write the received data to
677 * \param len Length of the receive buffer
678 *
679 * \returns If data has been received, the positive number of bytes received.
680 * \returns \c 0 if the connection has been closed.
681 * \returns If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ
682 * must be returned when the operation would block.
683 * \returns Another negative error code on other kinds of failures.
684 *
685 * \note The callback may receive fewer bytes than the length of the
686 * buffer. It must always return the number of bytes actually
687 * received and written to the buffer.
688 */
689 typedef int mbedtls_ssl_recv_t( void *ctx,
690 unsigned char *buf,
691 size_t len );
692
693 /**
694 * \brief Callback type: receive data from the network, with timeout
695 *
696 * \note That callback must block until data is received, or the
697 * timeout delay expires, or the operation is interrupted by a
698 * signal.
699 *
700 * \param ctx Context for the receive callback (typically a file descriptor)
701 * \param buf Buffer to write the received data to
702 * \param len Length of the receive buffer
703 * \param timeout Maximum number of milliseconds to wait for data
704 * 0 means no timeout (potentially waiting forever)
705 *
706 * \return The callback must return the number of bytes received,
707 * or a non-zero error code:
708 * \c MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out,
709 * \c MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal.
710 *
711 * \note The callback may receive fewer bytes than the length of the
712 * buffer. It must always return the number of bytes actually
713 * received and written to the buffer.
714 */
715 typedef int mbedtls_ssl_recv_timeout_t( void *ctx,
716 unsigned char *buf,
717 size_t len,
718 uint32_t timeout );
719 /**
720 * \brief Callback type: set a pair of timers/delays to watch
721 *
722 * \param ctx Context pointer
723 * \param int_ms Intermediate delay in milliseconds
724 * \param fin_ms Final delay in milliseconds
725 * 0 cancels the current timer.
726 *
727 * \note This callback must at least store the necessary information
728 * for the associated \c mbedtls_ssl_get_timer_t callback to
729 * return correct information.
730 *
731 * \note If using a event-driven style of programming, an event must
732 * be generated when the final delay is passed. The event must
733 * cause a call to \c mbedtls_ssl_handshake() with the proper
734 * SSL context to be scheduled. Care must be taken to ensure
735 * that at most one such call happens at a time.
736 *
737 * \note Only one timer at a time must be running. Calling this
738 * function while a timer is running must cancel it. Cancelled
739 * timers must not generate any event.
740 */
741 typedef void mbedtls_ssl_set_timer_t( void * ctx,
742 uint32_t int_ms,
743 uint32_t fin_ms );
744
745 /**
746 * \brief Callback type: get status of timers/delays
747 *
748 * \param ctx Context pointer
749 *
750 * \return This callback must return:
751 * -1 if cancelled (fin_ms == 0),
752 * 0 if none of the delays have passed,
753 * 1 if only the intermediate delay has passed,
754 * 2 if the final delay has passed.
755 */
756 typedef int mbedtls_ssl_get_timer_t( void * ctx );
757
758 /* Defined below */
759 typedef struct mbedtls_ssl_session mbedtls_ssl_session;
760 typedef struct mbedtls_ssl_context mbedtls_ssl_context;
761 typedef struct mbedtls_ssl_config mbedtls_ssl_config;
762
763 /* Defined in library/ssl_misc.h */
764 typedef struct mbedtls_ssl_transform mbedtls_ssl_transform;
765 typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params;
766 typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t;
767 #if defined(MBEDTLS_X509_CRT_PARSE_C)
768 typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert;
769 #endif
770 #if defined(MBEDTLS_SSL_PROTO_DTLS)
771 typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item;
772 #endif
773
774 /**
775 * \brief Callback type: server-side session cache getter
776 *
777 * The session cache is logically a key value store, with
778 * keys being session IDs and values being instances of
779 * mbedtls_ssl_session.
780 *
781 * This callback retrieves an entry in this key-value store.
782 *
783 * \param data The address of the session cache structure to query.
784 * \param session_id The buffer holding the session ID to query.
785 * \param session_id_len The length of \p session_id in Bytes.
786 * \param session The address of the session structure to populate.
787 * It is initialized with mbdtls_ssl_session_init(),
788 * and the callback must always leave it in a state
789 * where it can safely be freed via
790 * mbedtls_ssl_session_free() independent of the
791 * return code of this function.
792 *
793 * \return \c 0 on success
794 * \return A non-zero return value on failure.
795 *
796 */
797 typedef int mbedtls_ssl_cache_get_t( void *data,
798 unsigned char const *session_id,
799 size_t session_id_len,
800 mbedtls_ssl_session *session );
801 /**
802 * \brief Callback type: server-side session cache setter
803 *
804 * The session cache is logically a key value store, with
805 * keys being session IDs and values being instances of
806 * mbedtls_ssl_session.
807 *
808 * This callback sets an entry in this key-value store.
809 *
810 * \param data The address of the session cache structure to modify.
811 * \param session_id The buffer holding the session ID to query.
812 * \param session_id_len The length of \p session_id in Bytes.
813 * \param session The address of the session to be stored in the
814 * session cache.
815 *
816 * \return \c 0 on success
817 * \return A non-zero return value on failure.
818 */
819 typedef int mbedtls_ssl_cache_set_t( void *data,
820 unsigned char const *session_id,
821 size_t session_id_len,
822 const mbedtls_ssl_session *session );
823
824 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
825 #if defined(MBEDTLS_X509_CRT_PARSE_C)
826 /**
827 * \brief Callback type: start external signature operation.
828 *
829 * This callback is called during an SSL handshake to start
830 * a signature decryption operation using an
831 * external processor. The parameter \p cert contains
832 * the public key; it is up to the callback function to
833 * determine how to access the associated private key.
834 *
835 * This function typically sends or enqueues a request, and
836 * does not wait for the operation to complete. This allows
837 * the handshake step to be non-blocking.
838 *
839 * The parameters \p ssl and \p cert are guaranteed to remain
840 * valid throughout the handshake. On the other hand, this
841 * function must save the contents of \p hash if the value
842 * is needed for later processing, because the \p hash buffer
843 * is no longer valid after this function returns.
844 *
845 * This function may call mbedtls_ssl_set_async_operation_data()
846 * to store an operation context for later retrieval
847 * by the resume or cancel callback.
848 *
849 * \note For RSA signatures, this function must produce output
850 * that is consistent with PKCS#1 v1.5 in the same way as
851 * mbedtls_rsa_pkcs1_sign(). Before the private key operation,
852 * apply the padding steps described in RFC 8017, section 9.2
853 * "EMSA-PKCS1-v1_5" as follows.
854 * - If \p md_alg is #MBEDTLS_MD_NONE, apply the PKCS#1 v1.5
855 * encoding, treating \p hash as the DigestInfo to be
856 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
857 * from step 3, with `T = hash` and `tLen = hash_len`.
858 * - If `md_alg != MBEDTLS_MD_NONE`, apply the PKCS#1 v1.5
859 * encoding, treating \p hash as the hash to be encoded and
860 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
861 * from step 2, with `digestAlgorithm` obtained by calling
862 * mbedtls_oid_get_oid_by_md() on \p md_alg.
863 *
864 * \note For ECDSA signatures, the output format is the DER encoding
865 * `Ecdsa-Sig-Value` defined in
866 * [RFC 4492 section 5.4](https://tools.ietf.org/html/rfc4492#section-5.4).
867 *
868 * \param ssl The SSL connection instance. It should not be
869 * modified other than via
870 * mbedtls_ssl_set_async_operation_data().
871 * \param cert Certificate containing the public key.
872 * In simple cases, this is one of the pointers passed to
873 * mbedtls_ssl_conf_own_cert() when configuring the SSL
874 * connection. However, if other callbacks are used, this
875 * property may not hold. For example, if an SNI callback
876 * is registered with mbedtls_ssl_conf_sni(), then
877 * this callback determines what certificate is used.
878 * \param md_alg Hash algorithm.
879 * \param hash Buffer containing the hash. This buffer is
880 * no longer valid when the function returns.
881 * \param hash_len Size of the \c hash buffer in bytes.
882 *
883 * \return 0 if the operation was started successfully and the SSL
884 * stack should call the resume callback immediately.
885 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
886 * was started successfully and the SSL stack should return
887 * immediately without calling the resume callback yet.
888 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
889 * processor does not support this key. The SSL stack will
890 * use the private key object instead.
891 * \return Any other error indicates a fatal failure and is
892 * propagated up the call chain. The callback should
893 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
894 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
895 * directed in the documentation of this callback.
896 */
897 typedef int mbedtls_ssl_async_sign_t( mbedtls_ssl_context *ssl,
898 mbedtls_x509_crt *cert,
899 mbedtls_md_type_t md_alg,
900 const unsigned char *hash,
901 size_t hash_len );
902
903 /**
904 * \brief Callback type: start external decryption operation.
905 *
906 * This callback is called during an SSL handshake to start
907 * an RSA decryption operation using an
908 * external processor. The parameter \p cert contains
909 * the public key; it is up to the callback function to
910 * determine how to access the associated private key.
911 *
912 * This function typically sends or enqueues a request, and
913 * does not wait for the operation to complete. This allows
914 * the handshake step to be non-blocking.
915 *
916 * The parameters \p ssl and \p cert are guaranteed to remain
917 * valid throughout the handshake. On the other hand, this
918 * function must save the contents of \p input if the value
919 * is needed for later processing, because the \p input buffer
920 * is no longer valid after this function returns.
921 *
922 * This function may call mbedtls_ssl_set_async_operation_data()
923 * to store an operation context for later retrieval
924 * by the resume or cancel callback.
925 *
926 * \warning RSA decryption as used in TLS is subject to a potential
927 * timing side channel attack first discovered by Bleichenbacher
928 * in 1998. This attack can be remotely exploitable
929 * in practice. To avoid this attack, you must ensure that
930 * if the callback performs an RSA decryption, the time it
931 * takes to execute and return the result does not depend
932 * on whether the RSA decryption succeeded or reported
933 * invalid padding.
934 *
935 * \param ssl The SSL connection instance. It should not be
936 * modified other than via
937 * mbedtls_ssl_set_async_operation_data().
938 * \param cert Certificate containing the public key.
939 * In simple cases, this is one of the pointers passed to
940 * mbedtls_ssl_conf_own_cert() when configuring the SSL
941 * connection. However, if other callbacks are used, this
942 * property may not hold. For example, if an SNI callback
943 * is registered with mbedtls_ssl_conf_sni(), then
944 * this callback determines what certificate is used.
945 * \param input Buffer containing the input ciphertext. This buffer
946 * is no longer valid when the function returns.
947 * \param input_len Size of the \p input buffer in bytes.
948 *
949 * \return 0 if the operation was started successfully and the SSL
950 * stack should call the resume callback immediately.
951 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
952 * was started successfully and the SSL stack should return
953 * immediately without calling the resume callback yet.
954 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
955 * processor does not support this key. The SSL stack will
956 * use the private key object instead.
957 * \return Any other error indicates a fatal failure and is
958 * propagated up the call chain. The callback should
959 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
960 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
961 * directed in the documentation of this callback.
962 */
963 typedef int mbedtls_ssl_async_decrypt_t( mbedtls_ssl_context *ssl,
964 mbedtls_x509_crt *cert,
965 const unsigned char *input,
966 size_t input_len );
967 #endif /* MBEDTLS_X509_CRT_PARSE_C */
968
969 /**
970 * \brief Callback type: resume external operation.
971 *
972 * This callback is called during an SSL handshake to resume
973 * an external operation started by the
974 * ::mbedtls_ssl_async_sign_t or
975 * ::mbedtls_ssl_async_decrypt_t callback.
976 *
977 * This function typically checks the status of a pending
978 * request or causes the request queue to make progress, and
979 * does not wait for the operation to complete. This allows
980 * the handshake step to be non-blocking.
981 *
982 * This function may call mbedtls_ssl_get_async_operation_data()
983 * to retrieve an operation context set by the start callback.
984 * It may call mbedtls_ssl_set_async_operation_data() to modify
985 * this context.
986 *
987 * Note that when this function returns a status other than
988 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, it must free any
989 * resources associated with the operation.
990 *
991 * \param ssl The SSL connection instance. It should not be
992 * modified other than via
993 * mbedtls_ssl_set_async_operation_data().
994 * \param output Buffer containing the output (signature or decrypted
995 * data) on success.
996 * \param output_len On success, number of bytes written to \p output.
997 * \param output_size Size of the \p output buffer in bytes.
998 *
999 * \return 0 if output of the operation is available in the
1000 * \p output buffer.
1001 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
1002 * is still in progress. Subsequent requests for progress
1003 * on the SSL connection will call the resume callback
1004 * again.
1005 * \return Any other error means that the operation is aborted.
1006 * The SSL handshake is aborted. The callback should
1007 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
1008 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
1009 * directed in the documentation of this callback.
1010 */
1011 typedef int mbedtls_ssl_async_resume_t( mbedtls_ssl_context *ssl,
1012 unsigned char *output,
1013 size_t *output_len,
1014 size_t output_size );
1015
1016 /**
1017 * \brief Callback type: cancel external operation.
1018 *
1019 * This callback is called if an SSL connection is closed
1020 * while an asynchronous operation is in progress. Note that
1021 * this callback is not called if the
1022 * ::mbedtls_ssl_async_resume_t callback has run and has
1023 * returned a value other than
1024 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, since in that case
1025 * the asynchronous operation has already completed.
1026 *
1027 * This function may call mbedtls_ssl_get_async_operation_data()
1028 * to retrieve an operation context set by the start callback.
1029 *
1030 * \param ssl The SSL connection instance. It should not be
1031 * modified.
1032 */
1033 typedef void mbedtls_ssl_async_cancel_t( mbedtls_ssl_context *ssl );
1034 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1035
1036 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) && \
1037 !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
1038 #define MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN 48
1039 #if defined(MBEDTLS_SHA256_C)
1040 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA256
1041 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 32
1042 #elif defined(MBEDTLS_SHA384_C)
1043 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA384
1044 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 48
1045 #elif defined(MBEDTLS_SHA1_C)
1046 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA1
1047 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 20
1048 #else
1049 /* This is already checked in check_config.h, but be sure. */
1050 #error "Bad configuration - need SHA-1, SHA-256 or SHA-512 enabled to compute digest of peer CRT."
1051 #endif
1052 #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED &&
1053 !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1054
1055 typedef struct
1056 {
1057 unsigned char client_application_traffic_secret_N[ MBEDTLS_TLS1_3_MD_MAX_SIZE ];
1058 unsigned char server_application_traffic_secret_N[ MBEDTLS_TLS1_3_MD_MAX_SIZE ];
1059 unsigned char exporter_master_secret [ MBEDTLS_TLS1_3_MD_MAX_SIZE ];
1060 unsigned char resumption_master_secret [ MBEDTLS_TLS1_3_MD_MAX_SIZE ];
1061 } mbedtls_ssl_tls1_3_application_secrets;
1062
1063 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1064
1065 #define MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH 255
1066 #define MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH 4
1067 /*
1068 * For code readability use a typedef for DTLS-SRTP profiles
1069 *
1070 * Use_srtp extension protection profiles values as defined in
1071 * http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
1072 *
1073 * Reminder: if this list is expanded mbedtls_ssl_check_srtp_profile_value
1074 * must be updated too.
1075 */
1076 #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80 ( (uint16_t) 0x0001)
1077 #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32 ( (uint16_t) 0x0002)
1078 #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80 ( (uint16_t) 0x0005)
1079 #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32 ( (uint16_t) 0x0006)
1080 /* This one is not iana defined, but for code readability. */
1081 #define MBEDTLS_TLS_SRTP_UNSET ( (uint16_t) 0x0000)
1082
1083 typedef uint16_t mbedtls_ssl_srtp_profile;
1084
1085 typedef struct mbedtls_dtls_srtp_info_t
1086 {
1087 /*! The SRTP profile that was negotiated. */
1088 mbedtls_ssl_srtp_profile MBEDTLS_PRIVATE(chosen_dtls_srtp_profile);
1089 /*! The length of mki_value. */
1090 uint16_t MBEDTLS_PRIVATE(mki_len);
1091 /*! The mki_value used, with max size of 256 bytes. */
1092 unsigned char MBEDTLS_PRIVATE(mki_value)[MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH];
1093 }
1094 mbedtls_dtls_srtp_info;
1095
1096 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1097
1098 /*
1099 * This structure is used for storing current session data.
1100 *
1101 * Note: when changing this definition, we need to check and update:
1102 * - in tests/suites/test_suite_ssl.function:
1103 * ssl_populate_session() and ssl_serialize_session_save_load()
1104 * - in library/ssl_tls.c:
1105 * mbedtls_ssl_session_init() and mbedtls_ssl_session_free()
1106 * mbedtls_ssl_session_save() and ssl_session_load()
1107 * ssl_session_copy()
1108 */
1109 struct mbedtls_ssl_session
1110 {
1111 #if defined(MBEDTLS_HAVE_TIME)
1112 mbedtls_time_t MBEDTLS_PRIVATE(start); /*!< starting time */
1113 #endif
1114 int MBEDTLS_PRIVATE(ciphersuite); /*!< chosen ciphersuite */
1115 int MBEDTLS_PRIVATE(compression); /*!< chosen compression */
1116 size_t MBEDTLS_PRIVATE(id_len); /*!< session id length */
1117 unsigned char MBEDTLS_PRIVATE(id)[32]; /*!< session identifier */
1118 unsigned char MBEDTLS_PRIVATE(master)[48]; /*!< the master secret */
1119
1120 unsigned char MBEDTLS_PRIVATE(exported);
1121
1122 /* This field is temporarily duplicated with mbedtls_ssl_context.minor_ver.
1123 * Once runtime negotiation of TLS 1.2 and TLS 1.3 is implemented, it needs
1124 * to be studied whether one of them can be removed. */
1125 unsigned char MBEDTLS_PRIVATE(minor_ver); /*!< The TLS version used in the session. */
1126
1127 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1128 #if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
1129 mbedtls_x509_crt *MBEDTLS_PRIVATE(peer_cert); /*!< peer X.509 cert chain */
1130 #else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1131 /*! The digest of the peer's end-CRT. This must be kept to detect CRT
1132 * changes during renegotiation, mitigating the triple handshake attack. */
1133 unsigned char *MBEDTLS_PRIVATE(peer_cert_digest);
1134 size_t MBEDTLS_PRIVATE(peer_cert_digest_len);
1135 mbedtls_md_type_t MBEDTLS_PRIVATE(peer_cert_digest_type);
1136 #endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1137 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1138 uint32_t MBEDTLS_PRIVATE(verify_result); /*!< verification result */
1139
1140 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
1141 unsigned char *MBEDTLS_PRIVATE(ticket); /*!< RFC 5077 session ticket */
1142 size_t MBEDTLS_PRIVATE(ticket_len); /*!< session ticket length */
1143 uint32_t MBEDTLS_PRIVATE(ticket_lifetime); /*!< ticket lifetime hint */
1144 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
1145
1146 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
1147 unsigned char MBEDTLS_PRIVATE(mfl_code); /*!< MaxFragmentLength negotiated by peer */
1148 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
1149
1150 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1151 int MBEDTLS_PRIVATE(encrypt_then_mac); /*!< flag for EtM activation */
1152 #endif
1153
1154 #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
1155 mbedtls_ssl_tls1_3_application_secrets MBEDTLS_PRIVATE(app_secrets);
1156 #endif
1157 };
1158
1159 /*
1160 * Identifiers for PRFs used in various versions of TLS.
1161 */
1162 typedef enum
1163 {
1164 MBEDTLS_SSL_TLS_PRF_NONE,
1165 MBEDTLS_SSL_TLS_PRF_SHA384,
1166 MBEDTLS_SSL_TLS_PRF_SHA256,
1167 MBEDTLS_SSL_HKDF_EXPAND_SHA384,
1168 MBEDTLS_SSL_HKDF_EXPAND_SHA256
1169 }
1170 mbedtls_tls_prf_types;
1171
1172 typedef enum
1173 {
1174 MBEDTLS_SSL_KEY_EXPORT_TLS12_MASTER_SECRET = 0,
1175 #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
1176 MBEDTLS_SSL_KEY_EXPORT_TLS13_CLIENT_EARLY_SECRET,
1177 MBEDTLS_SSL_KEY_EXPORT_TLS13_EARLY_EXPORTER_SECRET,
1178 MBEDTLS_SSL_KEY_EXPORT_TLS13_CLIENT_HANDSHAKE_TRAFFIC_SECRET,
1179 MBEDTLS_SSL_KEY_EXPORT_TLS13_SERVER_HANDSHAKE_TRAFFIC_SECRET,
1180 MBEDTLS_SSL_KEY_EXPORT_TLS13_CLIENT_APPLICATION_TRAFFIC_SECRET,
1181 MBEDTLS_SSL_KEY_EXPORT_TLS13_SERVER_APPLICATION_TRAFFIC_SECRET,
1182 #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
1183 } mbedtls_ssl_key_export_type;
1184
1185 /**
1186 * \brief Callback type: Export key alongside random values for
1187 * session identification, and PRF for
1188 * implementation of TLS key exporters.
1189 *
1190 * \param p_expkey Context for the callback.
1191 * \param type The type of the key that is being exported.
1192 * \param secret The address of the buffer holding the secret
1193 * that's being exporterd.
1194 * \param secret_len The length of \p secret in bytes.
1195 * \param client_random The client random bytes.
1196 * \param server_random The server random bytes.
1197 * \param tls_prf_type The identifier for the PRF used in the handshake
1198 * to which the key belongs.
1199 */
1200 typedef void mbedtls_ssl_export_keys_t( void *p_expkey,
1201 mbedtls_ssl_key_export_type type,
1202 const unsigned char *secret,
1203 size_t secret_len,
1204 const unsigned char client_random[32],
1205 const unsigned char server_random[32],
1206 mbedtls_tls_prf_types tls_prf_type );
1207
1208 /**
1209 * SSL/TLS configuration to be shared between mbedtls_ssl_context structures.
1210 */
1211 struct mbedtls_ssl_config
1212 {
1213 /* Group items by size (largest first) to minimize padding overhead */
1214
1215 /*
1216 * Pointers
1217 */
1218
1219 /** Allowed ciphersuites for (D)TLS 1.2 (0-terminated) */
1220 const int *MBEDTLS_PRIVATE(ciphersuite_list);
1221
1222 #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
1223 /** Allowed TLS 1.3 key exchange modes. */
1224 int MBEDTLS_PRIVATE(tls13_kex_modes);
1225 #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
1226
1227 /** Callback for printing debug output */
1228 void (*MBEDTLS_PRIVATE(f_dbg))(void *, int, const char *, int, const char *);
1229 void *MBEDTLS_PRIVATE(p_dbg); /*!< context for the debug function */
1230
1231 /** Callback for getting (pseudo-)random numbers */
1232 int (*MBEDTLS_PRIVATE(f_rng))(void *, unsigned char *, size_t);
1233 void *MBEDTLS_PRIVATE(p_rng); /*!< context for the RNG function */
1234
1235 /** Callback to retrieve a session from the cache */
1236 mbedtls_ssl_cache_get_t *MBEDTLS_PRIVATE(f_get_cache);
1237 /** Callback to store a session into the cache */
1238 mbedtls_ssl_cache_set_t *MBEDTLS_PRIVATE(f_set_cache);
1239 void *MBEDTLS_PRIVATE(p_cache); /*!< context for cache callbacks */
1240
1241 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
1242 /** Callback for setting cert according to SNI extension */
1243 int (*MBEDTLS_PRIVATE(f_sni))(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
1244 void *MBEDTLS_PRIVATE(p_sni); /*!< context for SNI callback */
1245 #endif
1246
1247 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1248 /** Callback to customize X.509 certificate chain verification */
1249 int (*MBEDTLS_PRIVATE(f_vrfy))(void *, mbedtls_x509_crt *, int, uint32_t *);
1250 void *MBEDTLS_PRIVATE(p_vrfy); /*!< context for X.509 verify calllback */
1251 #endif
1252
1253 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
1254 /** Callback to retrieve PSK key from identity */
1255 int (*MBEDTLS_PRIVATE(f_psk))(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
1256 void *MBEDTLS_PRIVATE(p_psk); /*!< context for PSK callback */
1257 #endif
1258
1259 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1260 /** Callback to create & write a cookie for ClientHello veirifcation */
1261 int (*MBEDTLS_PRIVATE(f_cookie_write))( void *, unsigned char **, unsigned char *,
1262 const unsigned char *, size_t );
1263 /** Callback to verify validity of a ClientHello cookie */
1264 int (*MBEDTLS_PRIVATE(f_cookie_check))( void *, const unsigned char *, size_t,
1265 const unsigned char *, size_t );
1266 void *MBEDTLS_PRIVATE(p_cookie); /*!< context for the cookie callbacks */
1267 #endif
1268
1269 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
1270 /** Callback to create & write a session ticket */
1271 int (*MBEDTLS_PRIVATE(f_ticket_write))( void *, const mbedtls_ssl_session *,
1272 unsigned char *, const unsigned char *, size_t *, uint32_t * );
1273 /** Callback to parse a session ticket into a session structure */
1274 int (*MBEDTLS_PRIVATE(f_ticket_parse))( void *, mbedtls_ssl_session *, unsigned char *, size_t);
1275 void *MBEDTLS_PRIVATE(p_ticket); /*!< context for the ticket callbacks */
1276 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
1277
1278 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1279 size_t MBEDTLS_PRIVATE(cid_len); /*!< The length of CIDs for incoming DTLS records. */
1280 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1281
1282 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1283 const mbedtls_x509_crt_profile *MBEDTLS_PRIVATE(cert_profile); /*!< verification profile */
1284 mbedtls_ssl_key_cert *MBEDTLS_PRIVATE(key_cert); /*!< own certificate/key pair(s) */
1285 mbedtls_x509_crt *MBEDTLS_PRIVATE(ca_chain); /*!< trusted CAs */
1286 mbedtls_x509_crl *MBEDTLS_PRIVATE(ca_crl); /*!< trusted CAs CRLs */
1287 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
1288 mbedtls_x509_crt_ca_cb_t MBEDTLS_PRIVATE(f_ca_cb);
1289 void *MBEDTLS_PRIVATE(p_ca_cb);
1290 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
1291 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1292
1293 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
1294 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1295 mbedtls_ssl_async_sign_t *MBEDTLS_PRIVATE(f_async_sign_start); /*!< start asynchronous signature operation */
1296 mbedtls_ssl_async_decrypt_t *MBEDTLS_PRIVATE(f_async_decrypt_start); /*!< start asynchronous decryption operation */
1297 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1298 mbedtls_ssl_async_resume_t *MBEDTLS_PRIVATE(f_async_resume); /*!< resume asynchronous operation */
1299 mbedtls_ssl_async_cancel_t *MBEDTLS_PRIVATE(f_async_cancel); /*!< cancel asynchronous operation */
1300 void *MBEDTLS_PRIVATE(p_async_config_data); /*!< Configuration data set by mbedtls_ssl_conf_async_private_cb(). */
1301 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1302
1303 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
1304 const int *MBEDTLS_PRIVATE(sig_hashes); /*!< allowed signature hashes */
1305
1306 #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
1307 const uint16_t *MBEDTLS_PRIVATE(tls13_sig_algs); /*!< allowed signature algorithms for TLS 1.3 */
1308 #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
1309 #endif
1310
1311 #if defined(MBEDTLS_ECP_C) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1312 const mbedtls_ecp_group_id *MBEDTLS_PRIVATE(curve_list); /*!< allowed curves */
1313 #endif
1314
1315 const uint16_t *MBEDTLS_PRIVATE(group_list); /*!< allowed IANA NamedGroups */
1316
1317 #if defined(MBEDTLS_DHM_C)
1318 mbedtls_mpi MBEDTLS_PRIVATE(dhm_P); /*!< prime modulus for DHM */
1319 mbedtls_mpi MBEDTLS_PRIVATE(dhm_G); /*!< generator for DHM */
1320 #endif
1321
1322 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
1323
1324 #if defined(MBEDTLS_USE_PSA_CRYPTO)
1325 psa_key_id_t MBEDTLS_PRIVATE(psk_opaque); /*!< PSA key slot holding opaque PSK. This field
1326 * should only be set via
1327 * mbedtls_ssl_conf_psk_opaque().
1328 * If either no PSK or a raw PSK have been
1329 * configured, this has value \c 0.
1330 */
1331 #endif /* MBEDTLS_USE_PSA_CRYPTO */
1332
1333 unsigned char *MBEDTLS_PRIVATE(psk); /*!< The raw pre-shared key. This field should
1334 * only be set via mbedtls_ssl_conf_psk().
1335 * If either no PSK or an opaque PSK
1336 * have been configured, this has value NULL. */
1337 size_t MBEDTLS_PRIVATE(psk_len); /*!< The length of the raw pre-shared key.
1338 * This field should only be set via
1339 * mbedtls_ssl_conf_psk().
1340 * Its value is non-zero if and only if
1341 * \c psk is not \c NULL. */
1342
1343 unsigned char *MBEDTLS_PRIVATE(psk_identity); /*!< The PSK identity for PSK negotiation.
1344 * This field should only be set via
1345 * mbedtls_ssl_conf_psk().
1346 * This is set if and only if either
1347 * \c psk or \c psk_opaque are set. */
1348 size_t MBEDTLS_PRIVATE(psk_identity_len);/*!< The length of PSK identity.
1349 * This field should only be set via
1350 * mbedtls_ssl_conf_psk().
1351 * Its value is non-zero if and only if
1352 * \c psk is not \c NULL or \c psk_opaque
1353 * is not \c 0. */
1354 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
1355
1356 #if defined(MBEDTLS_SSL_ALPN)
1357 const char **MBEDTLS_PRIVATE(alpn_list); /*!< ordered list of protocols */
1358 #endif
1359
1360 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1361 /*! ordered list of supported srtp profile */
1362 const mbedtls_ssl_srtp_profile *MBEDTLS_PRIVATE(dtls_srtp_profile_list);
1363 /*! number of supported profiles */
1364 size_t MBEDTLS_PRIVATE(dtls_srtp_profile_list_len);
1365 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1366
1367 /*
1368 * Numerical settings (int then char)
1369 */
1370
1371 uint32_t MBEDTLS_PRIVATE(read_timeout); /*!< timeout for mbedtls_ssl_read (ms) */
1372
1373 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1374 uint32_t MBEDTLS_PRIVATE(hs_timeout_min); /*!< initial value of the handshake
1375 retransmission timeout (ms) */
1376 uint32_t MBEDTLS_PRIVATE(hs_timeout_max); /*!< maximum value of the handshake
1377 retransmission timeout (ms) */
1378 #endif
1379
1380 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1381 int MBEDTLS_PRIVATE(renego_max_records); /*!< grace period for renegotiation */
1382 unsigned char MBEDTLS_PRIVATE(renego_period)[8]; /*!< value of the record counters
1383 that triggers renegotiation */
1384 #endif
1385
1386 unsigned int MBEDTLS_PRIVATE(badmac_limit); /*!< limit of records with a bad MAC */
1387
1388 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
1389 unsigned int MBEDTLS_PRIVATE(dhm_min_bitlen); /*!< min. bit length of the DHM prime */
1390 #endif
1391
1392 unsigned char MBEDTLS_PRIVATE(max_major_ver); /*!< max. major version used */
1393 unsigned char MBEDTLS_PRIVATE(max_minor_ver); /*!< max. minor version used */
1394 unsigned char MBEDTLS_PRIVATE(min_major_ver); /*!< min. major version used */
1395 unsigned char MBEDTLS_PRIVATE(min_minor_ver); /*!< min. minor version used */
1396
1397 /*
1398 * Flags (bitfields)
1399 */
1400
1401 unsigned int MBEDTLS_PRIVATE(endpoint) : 1; /*!< 0: client, 1: server */
1402 unsigned int MBEDTLS_PRIVATE(transport) : 1; /*!< stream (TLS) or datagram (DTLS) */
1403 unsigned int MBEDTLS_PRIVATE(authmode) : 2; /*!< MBEDTLS_SSL_VERIFY_XXX */
1404 /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE */
1405 unsigned int MBEDTLS_PRIVATE(allow_legacy_renegotiation) : 2 ; /*!< MBEDTLS_LEGACY_XXX */
1406 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
1407 unsigned int MBEDTLS_PRIVATE(mfl_code) : 3; /*!< desired fragment length */
1408 #endif
1409 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1410 unsigned int MBEDTLS_PRIVATE(encrypt_then_mac) : 1 ; /*!< negotiate encrypt-then-mac? */
1411 #endif
1412 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
1413 unsigned int MBEDTLS_PRIVATE(extended_ms) : 1; /*!< negotiate extended master secret? */
1414 #endif
1415 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1416 unsigned int MBEDTLS_PRIVATE(anti_replay) : 1; /*!< detect and prevent replay? */
1417 #endif
1418 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1419 unsigned int MBEDTLS_PRIVATE(disable_renegotiation) : 1; /*!< disable renegotiation? */
1420 #endif
1421 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
1422 unsigned int MBEDTLS_PRIVATE(session_tickets) : 1; /*!< use session tickets? */
1423 #endif
1424 #if defined(MBEDTLS_SSL_SRV_C)
1425 unsigned int MBEDTLS_PRIVATE(cert_req_ca_list) : 1; /*!< enable sending CA list in
1426 Certificate Request messages? */
1427 unsigned int MBEDTLS_PRIVATE(respect_cli_pref) : 1; /*!< pick the ciphersuite according to
1428 the client's preferences rather
1429 than ours */
1430 #endif
1431 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1432 unsigned int MBEDTLS_PRIVATE(ignore_unexpected_cid) : 1; /*!< Determines whether DTLS
1433 * record with unexpected CID
1434 * should lead to failure. */
1435 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1436 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1437 unsigned int MBEDTLS_PRIVATE(dtls_srtp_mki_support) : 1; /* support having mki_value
1438 in the use_srtp extension */
1439 #endif
1440 };
1441
1442 struct mbedtls_ssl_context
1443 {
1444 const mbedtls_ssl_config *MBEDTLS_PRIVATE(conf); /*!< configuration information */
1445
1446 /*
1447 * Miscellaneous
1448 */
1449 int MBEDTLS_PRIVATE(state); /*!< SSL handshake: current state */
1450 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1451 int MBEDTLS_PRIVATE(renego_status); /*!< Initial, in progress, pending? */
1452 int MBEDTLS_PRIVATE(renego_records_seen); /*!< Records since renego request, or with DTLS,
1453 number of retransmissions of request if
1454 renego_max_records is < 0 */
1455 #endif /* MBEDTLS_SSL_RENEGOTIATION */
1456
1457 int MBEDTLS_PRIVATE(major_ver); /*!< equal to MBEDTLS_SSL_MAJOR_VERSION_3 */
1458
1459 /* This field is temporarily duplicated with mbedtls_ssl_context.minor_ver.
1460 * Once runtime negotiation of TLS 1.2 and TLS 1.3 is implemented, it needs
1461 * to be studied whether one of them can be removed. */
1462 int MBEDTLS_PRIVATE(minor_ver); /*!< one of MBEDTLS_SSL_MINOR_VERSION_x macros */
1463 unsigned MBEDTLS_PRIVATE(badmac_seen); /*!< records with a bad MAC received */
1464
1465 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1466 /** Callback to customize X.509 certificate chain verification */
1467 int (*MBEDTLS_PRIVATE(f_vrfy))(void *, mbedtls_x509_crt *, int, uint32_t *);
1468 void *MBEDTLS_PRIVATE(p_vrfy); /*!< context for X.509 verify callback */
1469 #endif
1470
1471 mbedtls_ssl_send_t *MBEDTLS_PRIVATE(f_send); /*!< Callback for network send */
1472 mbedtls_ssl_recv_t *MBEDTLS_PRIVATE(f_recv); /*!< Callback for network receive */
1473 mbedtls_ssl_recv_timeout_t *MBEDTLS_PRIVATE(f_recv_timeout);
1474 /*!< Callback for network receive with timeout */
1475
1476 void *MBEDTLS_PRIVATE(p_bio); /*!< context for I/O operations */
1477
1478 /*
1479 * Session layer
1480 */
1481 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_in); /*!< current session data (in) */
1482 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_out); /*!< current session data (out) */
1483 mbedtls_ssl_session *MBEDTLS_PRIVATE(session); /*!< negotiated session data */
1484 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_negotiate); /*!< session data in negotiation */
1485
1486 mbedtls_ssl_handshake_params *MBEDTLS_PRIVATE(handshake); /*!< params required only during
1487 the handshake process */
1488
1489 /*
1490 * Record layer transformations
1491 */
1492 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_in); /*!< current transform params (in)
1493 * This is always a reference,
1494 * never an owning pointer. */
1495 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_out); /*!< current transform params (out)
1496 * This is always a reference,
1497 * never an owning pointer. */
1498 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform); /*!< negotiated transform params
1499 * This pointer owns the transform
1500 * it references. */
1501 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_negotiate); /*!< transform params in negotiation
1502 * This pointer owns the transform
1503 * it references. */
1504
1505 #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
1506 /*! The application data transform in TLS 1.3.
1507 * This pointer owns the transform it references. */
1508 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_application);
1509 #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
1510
1511 /*
1512 * Timers
1513 */
1514 void *MBEDTLS_PRIVATE(p_timer); /*!< context for the timer callbacks */
1515
1516 mbedtls_ssl_set_timer_t *MBEDTLS_PRIVATE(f_set_timer); /*!< set timer callback */
1517 mbedtls_ssl_get_timer_t *MBEDTLS_PRIVATE(f_get_timer); /*!< get timer callback */
1518
1519 /*
1520 * Record layer (incoming data)
1521 */
1522 unsigned char *MBEDTLS_PRIVATE(in_buf); /*!< input buffer */
1523 unsigned char *MBEDTLS_PRIVATE(in_ctr); /*!< 64-bit incoming message counter
1524 TLS: maintained by us
1525 DTLS: read from peer */
1526 unsigned char *MBEDTLS_PRIVATE(in_hdr); /*!< start of record header */
1527 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1528 unsigned char *MBEDTLS_PRIVATE(in_cid); /*!< The start of the CID;
1529 * (the end is marked by in_len). */
1530 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1531 unsigned char *MBEDTLS_PRIVATE(in_len); /*!< two-bytes message length field */
1532 unsigned char *MBEDTLS_PRIVATE(in_iv); /*!< ivlen-byte IV */
1533 unsigned char *MBEDTLS_PRIVATE(in_msg); /*!< message contents (in_iv+ivlen) */
1534 unsigned char *MBEDTLS_PRIVATE(in_offt); /*!< read offset in application data */
1535
1536 int MBEDTLS_PRIVATE(in_msgtype); /*!< record header: message type */
1537 size_t MBEDTLS_PRIVATE(in_msglen); /*!< record header: message length */
1538 size_t MBEDTLS_PRIVATE(in_left); /*!< amount of data read so far */
1539 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1540 size_t MBEDTLS_PRIVATE(in_buf_len); /*!< length of input buffer */
1541 #endif
1542 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1543 uint16_t MBEDTLS_PRIVATE(in_epoch); /*!< DTLS epoch for incoming records */
1544 size_t MBEDTLS_PRIVATE(next_record_offset); /*!< offset of the next record in datagram
1545 (equal to in_left if none) */
1546 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1547 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1548 uint64_t MBEDTLS_PRIVATE(in_window_top); /*!< last validated record seq_num */
1549 uint64_t MBEDTLS_PRIVATE(in_window); /*!< bitmask for replay detection */
1550 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
1551
1552 size_t MBEDTLS_PRIVATE(in_hslen); /*!< current handshake message length,
1553 including the handshake header */
1554 int MBEDTLS_PRIVATE(nb_zero); /*!< # of 0-length encrypted messages */
1555
1556 int MBEDTLS_PRIVATE(keep_current_message); /*!< drop or reuse current message
1557 on next call to record layer? */
1558
1559 /* The following three variables indicate if and, if yes,
1560 * what kind of alert is pending to be sent.
1561 */
1562 unsigned char MBEDTLS_PRIVATE(send_alert); /*!< Determines if a fatal alert
1563 should be sent. Values:
1564 - \c 0 , no alert is to be sent.
1565 - \c 1 , alert is to be sent. */
1566 unsigned char MBEDTLS_PRIVATE(alert_type); /*!< Type of alert if send_alert
1567 != 0 */
1568 int MBEDTLS_PRIVATE(alert_reason); /*!< The error code to be returned
1569 to the user once the fatal alert
1570 has been sent. */
1571
1572 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1573 uint8_t MBEDTLS_PRIVATE(disable_datagram_packing); /*!< Disable packing multiple records
1574 * within a single datagram. */
1575 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1576
1577 /*
1578 * Record layer (outgoing data)
1579 */
1580 unsigned char *MBEDTLS_PRIVATE(out_buf); /*!< output buffer */
1581 unsigned char *MBEDTLS_PRIVATE(out_ctr); /*!< 64-bit outgoing message counter */
1582 unsigned char *MBEDTLS_PRIVATE(out_hdr); /*!< start of record header */
1583 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1584 unsigned char *MBEDTLS_PRIVATE(out_cid); /*!< The start of the CID;
1585 * (the end is marked by in_len). */
1586 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1587 unsigned char *MBEDTLS_PRIVATE(out_len); /*!< two-bytes message length field */
1588 unsigned char *MBEDTLS_PRIVATE(out_iv); /*!< ivlen-byte IV */
1589 unsigned char *MBEDTLS_PRIVATE(out_msg); /*!< message contents (out_iv+ivlen) */
1590
1591 int MBEDTLS_PRIVATE(out_msgtype); /*!< record header: message type */
1592 size_t MBEDTLS_PRIVATE(out_msglen); /*!< record header: message length */
1593 size_t MBEDTLS_PRIVATE(out_left); /*!< amount of data not yet written */
1594 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1595 size_t MBEDTLS_PRIVATE(out_buf_len); /*!< length of output buffer */
1596 #endif
1597
1598 unsigned char MBEDTLS_PRIVATE(cur_out_ctr)[MBEDTLS_SSL_SEQUENCE_NUMBER_LEN]; /*!< Outgoing record sequence number. */
1599
1600 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1601 uint16_t MBEDTLS_PRIVATE(mtu); /*!< path mtu, used to fragment outgoing messages */
1602 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1603
1604 /*
1605 * PKI layer
1606 */
1607 int MBEDTLS_PRIVATE(client_auth); /*!< flag for client auth. */
1608
1609 /*
1610 * User settings
1611 */
1612 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1613 char *MBEDTLS_PRIVATE(hostname); /*!< expected peer CN for verification
1614 (and SNI if available) */
1615 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1616
1617 #if defined(MBEDTLS_SSL_ALPN)
1618 const char *MBEDTLS_PRIVATE(alpn_chosen); /*!< negotiated protocol */
1619 #endif /* MBEDTLS_SSL_ALPN */
1620
1621 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1622 /*
1623 * use_srtp extension
1624 */
1625 mbedtls_dtls_srtp_info MBEDTLS_PRIVATE(dtls_srtp_info);
1626 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1627
1628 /*
1629 * Information for DTLS hello verify
1630 */
1631 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1632 unsigned char *MBEDTLS_PRIVATE(cli_id); /*!< transport-level ID of the client */
1633 size_t MBEDTLS_PRIVATE(cli_id_len); /*!< length of cli_id */
1634 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
1635
1636 /*
1637 * Secure renegotiation
1638 */
1639 /* needed to know when to send extension on server */
1640 int MBEDTLS_PRIVATE(secure_renegotiation); /*!< does peer support legacy or
1641 secure renegotiation */
1642 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1643 size_t MBEDTLS_PRIVATE(verify_data_len); /*!< length of verify data stored */
1644 char MBEDTLS_PRIVATE(own_verify_data)[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
1645 char MBEDTLS_PRIVATE(peer_verify_data)[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
1646 #endif /* MBEDTLS_SSL_RENEGOTIATION */
1647
1648 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1649 /* CID configuration to use in subsequent handshakes. */
1650
1651 /*! The next incoming CID, chosen by the user and applying to
1652 * all subsequent handshakes. This may be different from the
1653 * CID currently used in case the user has re-configured the CID
1654 * after an initial handshake. */
1655 unsigned char MBEDTLS_PRIVATE(own_cid)[ MBEDTLS_SSL_CID_IN_LEN_MAX ];
1656 uint8_t MBEDTLS_PRIVATE(own_cid_len); /*!< The length of \c own_cid. */
1657 uint8_t MBEDTLS_PRIVATE(negotiate_cid); /*!< This indicates whether the CID extension should
1658 * be negotiated in the next handshake or not.
1659 * Possible values are #MBEDTLS_SSL_CID_ENABLED
1660 * and #MBEDTLS_SSL_CID_DISABLED. */
1661 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1662
1663 /** Callback to export key block and master secret */
1664 mbedtls_ssl_export_keys_t *MBEDTLS_PRIVATE(f_export_keys);
1665 void *MBEDTLS_PRIVATE(p_export_keys); /*!< context for key export callback */
1666 };
1667
1668 /**
1669 * \brief Return the name of the ciphersuite associated with the
1670 * given ID
1671 *
1672 * \param ciphersuite_id SSL ciphersuite ID
1673 *
1674 * \return a string containing the ciphersuite name
1675 */
1676 const char *mbedtls_ssl_get_ciphersuite_name( const int ciphersuite_id );
1677
1678 /**
1679 * \brief Return the ID of the ciphersuite associated with the
1680 * given name
1681 *
1682 * \param ciphersuite_name SSL ciphersuite name
1683 *
1684 * \return the ID with the ciphersuite or 0 if not found
1685 */
1686 int mbedtls_ssl_get_ciphersuite_id( const char *ciphersuite_name );
1687
1688 /**
1689 * \brief Initialize an SSL context
1690 * Just makes the context ready for mbedtls_ssl_setup() or
1691 * mbedtls_ssl_free()
1692 *
1693 * \param ssl SSL context
1694 */
1695 void mbedtls_ssl_init( mbedtls_ssl_context *ssl );
1696
1697 /**
1698 * \brief Set up an SSL context for use
1699 *
1700 * \note No copy of the configuration context is made, it can be
1701 * shared by many mbedtls_ssl_context structures.
1702 *
1703 * \warning The conf structure will be accessed during the session.
1704 * It must not be modified or freed as long as the session
1705 * is active.
1706 *
1707 * \warning This function must be called exactly once per context.
1708 * Calling mbedtls_ssl_setup again is not supported, even
1709 * if no session is active.
1710 *
1711 * \param ssl SSL context
1712 * \param conf SSL configuration to use
1713 *
1714 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED if
1715 * memory allocation failed
1716 */
1717 int mbedtls_ssl_setup( mbedtls_ssl_context *ssl,
1718 const mbedtls_ssl_config *conf );
1719
1720 /**
1721 * \brief Reset an already initialized SSL context for re-use
1722 * while retaining application-set variables, function
1723 * pointers and data.
1724 *
1725 * \param ssl SSL context
1726 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED or
1727 MBEDTLS_ERR_SSL_HW_ACCEL_FAILED
1728 */
1729 int mbedtls_ssl_session_reset( mbedtls_ssl_context *ssl );
1730
1731 /**
1732 * \brief Set the current endpoint type
1733 *
1734 * \param conf SSL configuration
1735 * \param endpoint must be MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
1736 */
1737 void mbedtls_ssl_conf_endpoint( mbedtls_ssl_config *conf, int endpoint );
1738
1739 /**
1740 * \brief Set the transport type (TLS or DTLS).
1741 * Default: TLS
1742 *
1743 * \note For DTLS, you must either provide a recv callback that
1744 * doesn't block, or one that handles timeouts, see
1745 * \c mbedtls_ssl_set_bio(). You also need to provide timer
1746 * callbacks with \c mbedtls_ssl_set_timer_cb().
1747 *
1748 * \param conf SSL configuration
1749 * \param transport transport type:
1750 * MBEDTLS_SSL_TRANSPORT_STREAM for TLS,
1751 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS.
1752 */
1753 void mbedtls_ssl_conf_transport( mbedtls_ssl_config *conf, int transport );
1754
1755 /**
1756 * \brief Set the certificate verification mode
1757 * Default: NONE on server, REQUIRED on client
1758 *
1759 * \param conf SSL configuration
1760 * \param authmode can be:
1761 *
1762 * MBEDTLS_SSL_VERIFY_NONE: peer certificate is not checked
1763 * (default on server)
1764 * (insecure on client)
1765 *
1766 * MBEDTLS_SSL_VERIFY_OPTIONAL: peer certificate is checked, however the
1767 * handshake continues even if verification failed;
1768 * mbedtls_ssl_get_verify_result() can be called after the
1769 * handshake is complete.
1770 *
1771 * MBEDTLS_SSL_VERIFY_REQUIRED: peer *must* present a valid certificate,
1772 * handshake is aborted if verification failed.
1773 * (default on client)
1774 *
1775 * \note On client, MBEDTLS_SSL_VERIFY_REQUIRED is the recommended mode.
1776 * With MBEDTLS_SSL_VERIFY_OPTIONAL, the user needs to call mbedtls_ssl_get_verify_result() at
1777 * the right time(s), which may not be obvious, while REQUIRED always perform
1778 * the verification as soon as possible. For example, REQUIRED was protecting
1779 * against the "triple handshake" attack even before it was found.
1780 */
1781 void mbedtls_ssl_conf_authmode( mbedtls_ssl_config *conf, int authmode );
1782
1783 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1784 /**
1785 * \brief Set the verification callback (Optional).
1786 *
1787 * If set, the provided verify callback is called for each
1788 * certificate in the peer's CRT chain, including the trusted
1789 * root. For more information, please see the documentation of
1790 * \c mbedtls_x509_crt_verify().
1791 *
1792 * \note For per context callbacks and contexts, please use
1793 * mbedtls_ssl_set_verify() instead.
1794 *
1795 * \param conf The SSL configuration to use.
1796 * \param f_vrfy The verification callback to use during CRT verification.
1797 * \param p_vrfy The opaque context to be passed to the callback.
1798 */
1799 void mbedtls_ssl_conf_verify( mbedtls_ssl_config *conf,
1800 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
1801 void *p_vrfy );
1802 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1803
1804 /**
1805 * \brief Set the random number generator callback
1806 *
1807 * \param conf SSL configuration
1808 * \param f_rng RNG function (mandatory)
1809 * \param p_rng RNG parameter
1810 */
1811 void mbedtls_ssl_conf_rng( mbedtls_ssl_config *conf,
1812 int (*f_rng)(void *, unsigned char *, size_t),
1813 void *p_rng );
1814
1815 /**
1816 * \brief Set the debug callback
1817 *
1818 * The callback has the following argument:
1819 * void * opaque context for the callback
1820 * int debug level
1821 * const char * file name
1822 * int line number
1823 * const char * message
1824 *
1825 * \param conf SSL configuration
1826 * \param f_dbg debug function
1827 * \param p_dbg debug parameter
1828 */
1829 void mbedtls_ssl_conf_dbg( mbedtls_ssl_config *conf,
1830 void (*f_dbg)(void *, int, const char *, int, const char *),
1831 void *p_dbg );
1832
1833 /**
1834 * \brief Set the underlying BIO callbacks for write, read and
1835 * read-with-timeout.
1836 *
1837 * \param ssl SSL context
1838 * \param p_bio parameter (context) shared by BIO callbacks
1839 * \param f_send write callback
1840 * \param f_recv read callback
1841 * \param f_recv_timeout blocking read callback with timeout.
1842 *
1843 * \note One of f_recv or f_recv_timeout can be NULL, in which case
1844 * the other is used. If both are non-NULL, f_recv_timeout is
1845 * used and f_recv is ignored (as if it were NULL).
1846 *
1847 * \note The two most common use cases are:
1848 * - non-blocking I/O, f_recv != NULL, f_recv_timeout == NULL
1849 * - blocking I/O, f_recv == NULL, f_recv_timout != NULL
1850 *
1851 * \note For DTLS, you need to provide either a non-NULL
1852 * f_recv_timeout callback, or a f_recv that doesn't block.
1853 *
1854 * \note See the documentations of \c mbedtls_ssl_send_t,
1855 * \c mbedtls_ssl_recv_t and \c mbedtls_ssl_recv_timeout_t for
1856 * the conventions those callbacks must follow.
1857 *
1858 * \note On some platforms, net_sockets.c provides
1859 * \c mbedtls_net_send(), \c mbedtls_net_recv() and
1860 * \c mbedtls_net_recv_timeout() that are suitable to be used
1861 * here.
1862 */
1863 void mbedtls_ssl_set_bio( mbedtls_ssl_context *ssl,
1864 void *p_bio,
1865 mbedtls_ssl_send_t *f_send,
1866 mbedtls_ssl_recv_t *f_recv,
1867 mbedtls_ssl_recv_timeout_t *f_recv_timeout );
1868
1869 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1870
1871 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1872
1873
1874 /**
1875 * \brief Configure the use of the Connection ID (CID)
1876 * extension in the next handshake.
1877 *
1878 * Reference: draft-ietf-tls-dtls-connection-id-05
1879 * https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05
1880 *
1881 * The DTLS CID extension allows the reliable association of
1882 * DTLS records to DTLS connections across changes in the
1883 * underlying transport (changed IP and Port metadata) by
1884 * adding explicit connection identifiers (CIDs) to the
1885 * headers of encrypted DTLS records. The desired CIDs are
1886 * configured by the application layer and are exchanged in
1887 * new `ClientHello` / `ServerHello` extensions during the
1888 * handshake, where each side indicates the CID it wants the
1889 * peer to use when writing encrypted messages. The CIDs are
1890 * put to use once records get encrypted: the stack discards
1891 * any incoming records that don't include the configured CID
1892 * in their header, and adds the peer's requested CID to the
1893 * headers of outgoing messages.
1894 *
1895 * This API enables or disables the use of the CID extension
1896 * in the next handshake and sets the value of the CID to
1897 * be used for incoming messages.
1898 *
1899 * \param ssl The SSL context to configure. This must be initialized.
1900 * \param enable This value determines whether the CID extension should
1901 * be used or not. Possible values are:
1902 * - MBEDTLS_SSL_CID_ENABLED to enable the use of the CID.
1903 * - MBEDTLS_SSL_CID_DISABLED (default) to disable the use
1904 * of the CID.
1905 * \param own_cid The address of the readable buffer holding the CID we want
1906 * the peer to use when sending encrypted messages to us.
1907 * This may be \c NULL if \p own_cid_len is \c 0.
1908 * This parameter is unused if \p enabled is set to
1909 * MBEDTLS_SSL_CID_DISABLED.
1910 * \param own_cid_len The length of \p own_cid.
1911 * This parameter is unused if \p enabled is set to
1912 * MBEDTLS_SSL_CID_DISABLED.
1913 *
1914 * \note The value of \p own_cid_len must match the value of the
1915 * \c len parameter passed to mbedtls_ssl_conf_cid()
1916 * when configuring the ::mbedtls_ssl_config that \p ssl
1917 * is bound to.
1918 *
1919 * \note This CID configuration applies to subsequent handshakes
1920 * performed on the SSL context \p ssl, but does not trigger
1921 * one. You still have to call `mbedtls_ssl_handshake()`
1922 * (for the initial handshake) or `mbedtls_ssl_renegotiate()`
1923 * (for a renegotiation handshake) explicitly after a
1924 * successful call to this function to run the handshake.
1925 *
1926 * \note This call cannot guarantee that the use of the CID
1927 * will be successfully negotiated in the next handshake,
1928 * because the peer might not support it. Specifically:
1929 * - On the Client, enabling the use of the CID through
1930 * this call implies that the `ClientHello` in the next
1931 * handshake will include the CID extension, thereby
1932 * offering the use of the CID to the server. Only if
1933 * the `ServerHello` contains the CID extension, too,
1934 * the CID extension will actually be put to use.
1935 * - On the Server, enabling the use of the CID through
1936 * this call implies that that the server will look for
1937 * the CID extension in a `ClientHello` from the client,
1938 * and, if present, reply with a CID extension in its
1939 * `ServerHello`.
1940 *
1941 * \note To check whether the use of the CID was negotiated
1942 * after the subsequent handshake has completed, please
1943 * use the API mbedtls_ssl_get_peer_cid().
1944 *
1945 * \warning If the use of the CID extension is enabled in this call
1946 * and the subsequent handshake negotiates its use, Mbed TLS
1947 * will silently drop every packet whose CID does not match
1948 * the CID configured in \p own_cid. It is the responsibility
1949 * of the user to adapt the underlying transport to take care
1950 * of CID-based demultiplexing before handing datagrams to
1951 * Mbed TLS.
1952 *
1953 * \return \c 0 on success. In this case, the CID configuration
1954 * applies to the next handshake.
1955 * \return A negative error code on failure.
1956 */
1957 int mbedtls_ssl_set_cid( mbedtls_ssl_context *ssl,
1958 int enable,
1959 unsigned char const *own_cid,
1960 size_t own_cid_len );
1961
1962 /**
1963 * \brief Get information about the use of the CID extension
1964 * in the current connection.
1965 *
1966 * \param ssl The SSL context to query.
1967 * \param enabled The address at which to store whether the CID extension
1968 * is currently in use or not. If the CID is in use,
1969 * `*enabled` is set to MBEDTLS_SSL_CID_ENABLED;
1970 * otherwise, it is set to MBEDTLS_SSL_CID_DISABLED.
1971 * \param peer_cid The address of the buffer in which to store the CID
1972 * chosen by the peer (if the CID extension is used).
1973 * This may be \c NULL in case the value of peer CID
1974 * isn't needed. If it is not \c NULL, \p peer_cid_len
1975 * must not be \c NULL.
1976 * \param peer_cid_len The address at which to store the size of the CID
1977 * chosen by the peer (if the CID extension is used).
1978 * This is also the number of Bytes in \p peer_cid that
1979 * have been written.
1980 * This may be \c NULL in case the length of the peer CID
1981 * isn't needed. If it is \c NULL, \p peer_cid must be
1982 * \c NULL, too.
1983 *
1984 * \note This applies to the state of the CID negotiated in
1985 * the last complete handshake. If a handshake is in
1986 * progress, this function will attempt to complete
1987 * the handshake first.
1988 *
1989 * \note If CID extensions have been exchanged but both client
1990 * and server chose to use an empty CID, this function
1991 * sets `*enabled` to #MBEDTLS_SSL_CID_DISABLED
1992 * (the rationale for this is that the resulting
1993 * communication is the same as if the CID extensions
1994 * hadn't been used).
1995 *
1996 * \return \c 0 on success.
1997 * \return A negative error code on failure.
1998 */
1999 int mbedtls_ssl_get_peer_cid( mbedtls_ssl_context *ssl,
2000 int *enabled,
2001 unsigned char peer_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ],
2002 size_t *peer_cid_len );
2003
2004 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
2005
2006 /**
2007 * \brief Set the Maximum Tranport Unit (MTU).
2008 * Special value: 0 means unset (no limit).
2009 * This represents the maximum size of a datagram payload
2010 * handled by the transport layer (usually UDP) as determined
2011 * by the network link and stack. In practice, this controls
2012 * the maximum size datagram the DTLS layer will pass to the
2013 * \c f_send() callback set using \c mbedtls_ssl_set_bio().
2014 *
2015 * \note The limit on datagram size is converted to a limit on
2016 * record payload by subtracting the current overhead of
2017 * encapsulation and encryption/authentication if any.
2018 *
2019 * \note This can be called at any point during the connection, for
2020 * example when a Path Maximum Transfer Unit (PMTU)
2021 * estimate becomes available from other sources,
2022 * such as lower (or higher) protocol layers.
2023 *
2024 * \note This setting only controls the size of the packets we send,
2025 * and does not restrict the size of the datagrams we're
2026 * willing to receive. Client-side, you can request the
2027 * server to use smaller records with \c
2028 * mbedtls_ssl_conf_max_frag_len().
2029 *
2030 * \note If both a MTU and a maximum fragment length have been
2031 * configured (or negotiated with the peer), the resulting
2032 * lower limit on record payload (see first note) is used.
2033 *
2034 * \note This can only be used to decrease the maximum size
2035 * of datagrams (hence records, see first note) sent. It
2036 * cannot be used to increase the maximum size of records over
2037 * the limit set by #MBEDTLS_SSL_OUT_CONTENT_LEN.
2038 *
2039 * \note Values lower than the current record layer expansion will
2040 * result in an error when trying to send data.
2041 *
2042 * \param ssl SSL context
2043 * \param mtu Value of the path MTU in bytes
2044 */
2045 void mbedtls_ssl_set_mtu( mbedtls_ssl_context *ssl, uint16_t mtu );
2046 #endif /* MBEDTLS_SSL_PROTO_DTLS */
2047
2048 #if defined(MBEDTLS_X509_CRT_PARSE_C)
2049 /**
2050 * \brief Set a connection-specific verification callback (optional).
2051 *
2052 * If set, the provided verify callback is called for each
2053 * certificate in the peer's CRT chain, including the trusted
2054 * root. For more information, please see the documentation of
2055 * \c mbedtls_x509_crt_verify().
2056 *
2057 * \note This call is analogous to mbedtls_ssl_conf_verify() but
2058 * binds the verification callback and context to an SSL context
2059 * as opposed to an SSL configuration.
2060 * If mbedtls_ssl_conf_verify() and mbedtls_ssl_set_verify()
2061 * are both used, mbedtls_ssl_set_verify() takes precedence.
2062 *
2063 * \param ssl The SSL context to use.
2064 * \param f_vrfy The verification callback to use during CRT verification.
2065 * \param p_vrfy The opaque context to be passed to the callback.
2066 */
2067 void mbedtls_ssl_set_verify( mbedtls_ssl_context *ssl,
2068 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2069 void *p_vrfy );
2070 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2071
2072 /**
2073 * \brief Set the timeout period for mbedtls_ssl_read()
2074 * (Default: no timeout.)
2075 *
2076 * \param conf SSL configuration context
2077 * \param timeout Timeout value in milliseconds.
2078 * Use 0 for no timeout (default).
2079 *
2080 * \note With blocking I/O, this will only work if a non-NULL
2081 * \c f_recv_timeout was set with \c mbedtls_ssl_set_bio().
2082 * With non-blocking I/O, this will only work if timer
2083 * callbacks were set with \c mbedtls_ssl_set_timer_cb().
2084 *
2085 * \note With non-blocking I/O, you may also skip this function
2086 * altogether and handle timeouts at the application layer.
2087 */
2088 void mbedtls_ssl_conf_read_timeout( mbedtls_ssl_config *conf, uint32_t timeout );
2089
2090 /**
2091 * \brief Check whether a buffer contains a valid and authentic record
2092 * that has not been seen before. (DTLS only).
2093 *
2094 * This function does not change the user-visible state
2095 * of the SSL context. Its sole purpose is to provide
2096 * an indication of the legitimacy of an incoming record.
2097 *
2098 * This can be useful e.g. in distributed server environments
2099 * using the DTLS Connection ID feature, in which connections
2100 * might need to be passed between service instances on a change
2101 * of peer address, but where such disruptive operations should
2102 * only happen after the validity of incoming records has been
2103 * confirmed.
2104 *
2105 * \param ssl The SSL context to use.
2106 * \param buf The address of the buffer holding the record to be checked.
2107 * This must be a read/write buffer of length \p buflen Bytes.
2108 * \param buflen The length of \p buf in Bytes.
2109 *
2110 * \note This routine only checks whether the provided buffer begins
2111 * with a valid and authentic record that has not been seen
2112 * before, but does not check potential data following the
2113 * initial record. In particular, it is possible to pass DTLS
2114 * datagrams containing multiple records, in which case only
2115 * the first record is checked.
2116 *
2117 * \note This function modifies the input buffer \p buf. If you need
2118 * to preserve the original record, you have to maintain a copy.
2119 *
2120 * \return \c 0 if the record is valid and authentic and has not been
2121 * seen before.
2122 * \return MBEDTLS_ERR_SSL_INVALID_MAC if the check completed
2123 * successfully but the record was found to be not authentic.
2124 * \return MBEDTLS_ERR_SSL_INVALID_RECORD if the check completed
2125 * successfully but the record was found to be invalid for
2126 * a reason different from authenticity checking.
2127 * \return MBEDTLS_ERR_SSL_UNEXPECTED_RECORD if the check completed
2128 * successfully but the record was found to be unexpected
2129 * in the state of the SSL context, including replayed records.
2130 * \return Another negative error code on different kinds of failure.
2131 * In this case, the SSL context becomes unusable and needs
2132 * to be freed or reset before reuse.
2133 */
2134 int mbedtls_ssl_check_record( mbedtls_ssl_context const *ssl,
2135 unsigned char *buf,
2136 size_t buflen );
2137
2138 /**
2139 * \brief Set the timer callbacks (Mandatory for DTLS.)
2140 *
2141 * \param ssl SSL context
2142 * \param p_timer parameter (context) shared by timer callbacks
2143 * \param f_set_timer set timer callback
2144 * \param f_get_timer get timer callback. Must return:
2145 *
2146 * \note See the documentation of \c mbedtls_ssl_set_timer_t and
2147 * \c mbedtls_ssl_get_timer_t for the conventions this pair of
2148 * callbacks must follow.
2149 *
2150 * \note On some platforms, timing.c provides
2151 * \c mbedtls_timing_set_delay() and
2152 * \c mbedtls_timing_get_delay() that are suitable for using
2153 * here, except if using an event-driven style.
2154 *
2155 * \note See also the "DTLS tutorial" article in our knowledge base.
2156 * https://tls.mbed.org/kb/how-to/dtls-tutorial
2157 */
2158 void mbedtls_ssl_set_timer_cb( mbedtls_ssl_context *ssl,
2159 void *p_timer,
2160 mbedtls_ssl_set_timer_t *f_set_timer,
2161 mbedtls_ssl_get_timer_t *f_get_timer );
2162
2163 /**
2164 * \brief Callback type: generate and write session ticket
2165 *
2166 * \note This describes what a callback implementation should do.
2167 * This callback should generate an encrypted and
2168 * authenticated ticket for the session and write it to the
2169 * output buffer. Here, ticket means the opaque ticket part
2170 * of the NewSessionTicket structure of RFC 5077.
2171 *
2172 * \param p_ticket Context for the callback
2173 * \param session SSL session to be written in the ticket
2174 * \param start Start of the output buffer
2175 * \param end End of the output buffer
2176 * \param tlen On exit, holds the length written
2177 * \param lifetime On exit, holds the lifetime of the ticket in seconds
2178 *
2179 * \return 0 if successful, or
2180 * a specific MBEDTLS_ERR_XXX code.
2181 */
2182 typedef int mbedtls_ssl_ticket_write_t( void *p_ticket,
2183 const mbedtls_ssl_session *session,
2184 unsigned char *start,
2185 const unsigned char *end,
2186 size_t *tlen,
2187 uint32_t *lifetime );
2188
2189 /**
2190 * \brief Callback type: parse and load session ticket
2191 *
2192 * \note This describes what a callback implementation should do.
2193 * This callback should parse a session ticket as generated
2194 * by the corresponding mbedtls_ssl_ticket_write_t function,
2195 * and, if the ticket is authentic and valid, load the
2196 * session.
2197 *
2198 * \note The implementation is allowed to modify the first len
2199 * bytes of the input buffer, eg to use it as a temporary
2200 * area for the decrypted ticket contents.
2201 *
2202 * \param p_ticket Context for the callback
2203 * \param session SSL session to be loaded
2204 * \param buf Start of the buffer containing the ticket
2205 * \param len Length of the ticket.
2206 *
2207 * \return 0 if successful, or
2208 * MBEDTLS_ERR_SSL_INVALID_MAC if not authentic, or
2209 * MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED if expired, or
2210 * any other non-zero code for other failures.
2211 */
2212 typedef int mbedtls_ssl_ticket_parse_t( void *p_ticket,
2213 mbedtls_ssl_session *session,
2214 unsigned char *buf,
2215 size_t len );
2216
2217 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
2218 /**
2219 * \brief Configure SSL session ticket callbacks (server only).
2220 * (Default: none.)
2221 *
2222 * \note On server, session tickets are enabled by providing
2223 * non-NULL callbacks.
2224 *
2225 * \note On client, use \c mbedtls_ssl_conf_session_tickets().
2226 *
2227 * \param conf SSL configuration context
2228 * \param f_ticket_write Callback for writing a ticket
2229 * \param f_ticket_parse Callback for parsing a ticket
2230 * \param p_ticket Context shared by the two callbacks
2231 */
2232 void mbedtls_ssl_conf_session_tickets_cb( mbedtls_ssl_config *conf,
2233 mbedtls_ssl_ticket_write_t *f_ticket_write,
2234 mbedtls_ssl_ticket_parse_t *f_ticket_parse,
2235 void *p_ticket );
2236 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
2237
2238 /**
2239 * \brief Configure a key export callback.
2240 * (Default: none.)
2241 *
2242 * This API can be used for two purposes:
2243 * - Debugging: Use this API to e.g. generate an NSSKeylog
2244 * file and use it to inspect encrypted traffic in tools
2245 * such as Wireshark.
2246 * - Application-specific export: Use this API to implement
2247 * key exporters, e.g. for EAP-TLS or DTLS-SRTP.
2248 *
2249 *
2250 * \param ssl The SSL context to which the export
2251 * callback should be attached.
2252 * \param f_export_keys The callback for the key export.
2253 * \param p_export_keys The opaque context pointer to be passed to the
2254 * callback \p f_export_keys.
2255 */
2256 void mbedtls_ssl_set_export_keys_cb( mbedtls_ssl_context *ssl,
2257 mbedtls_ssl_export_keys_t *f_export_keys,
2258 void *p_export_keys );
2259
2260 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
2261 /**
2262 * \brief Configure asynchronous private key operation callbacks.
2263 *
2264 * \param conf SSL configuration context
2265 * \param f_async_sign Callback to start a signature operation. See
2266 * the description of ::mbedtls_ssl_async_sign_t
2267 * for more information. This may be \c NULL if the
2268 * external processor does not support any signature
2269 * operation; in this case the private key object
2270 * associated with the certificate will be used.
2271 * \param f_async_decrypt Callback to start a decryption operation. See
2272 * the description of ::mbedtls_ssl_async_decrypt_t
2273 * for more information. This may be \c NULL if the
2274 * external processor does not support any decryption
2275 * operation; in this case the private key object
2276 * associated with the certificate will be used.
2277 * \param f_async_resume Callback to resume an asynchronous operation. See
2278 * the description of ::mbedtls_ssl_async_resume_t
2279 * for more information. This may not be \c NULL unless
2280 * \p f_async_sign and \p f_async_decrypt are both
2281 * \c NULL.
2282 * \param f_async_cancel Callback to cancel an asynchronous operation. See
2283 * the description of ::mbedtls_ssl_async_cancel_t
2284 * for more information. This may be \c NULL if
2285 * no cleanup is needed.
2286 * \param config_data A pointer to configuration data which can be
2287 * retrieved with
2288 * mbedtls_ssl_conf_get_async_config_data(). The
2289 * library stores this value without dereferencing it.
2290 */
2291 void mbedtls_ssl_conf_async_private_cb( mbedtls_ssl_config *conf,
2292 mbedtls_ssl_async_sign_t *f_async_sign,
2293 mbedtls_ssl_async_decrypt_t *f_async_decrypt,
2294 mbedtls_ssl_async_resume_t *f_async_resume,
2295 mbedtls_ssl_async_cancel_t *f_async_cancel,
2296 void *config_data );
2297
2298 /**
2299 * \brief Retrieve the configuration data set by
2300 * mbedtls_ssl_conf_async_private_cb().
2301 *
2302 * \param conf SSL configuration context
2303 * \return The configuration data set by
2304 * mbedtls_ssl_conf_async_private_cb().
2305 */
2306 void *mbedtls_ssl_conf_get_async_config_data( const mbedtls_ssl_config *conf );
2307
2308 /**
2309 * \brief Retrieve the asynchronous operation user context.
2310 *
2311 * \note This function may only be called while a handshake
2312 * is in progress.
2313 *
2314 * \param ssl The SSL context to access.
2315 *
2316 * \return The asynchronous operation user context that was last
2317 * set during the current handshake. If
2318 * mbedtls_ssl_set_async_operation_data() has not yet been
2319 * called during the current handshake, this function returns
2320 * \c NULL.
2321 */
2322 void *mbedtls_ssl_get_async_operation_data( const mbedtls_ssl_context *ssl );
2323
2324 /**
2325 * \brief Retrieve the asynchronous operation user context.
2326 *
2327 * \note This function may only be called while a handshake
2328 * is in progress.
2329 *
2330 * \param ssl The SSL context to access.
2331 * \param ctx The new value of the asynchronous operation user context.
2332 * Call mbedtls_ssl_get_async_operation_data() later during the
2333 * same handshake to retrieve this value.
2334 */
2335 void mbedtls_ssl_set_async_operation_data( mbedtls_ssl_context *ssl,
2336 void *ctx );
2337 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
2338
2339 /**
2340 * \brief Callback type: generate a cookie
2341 *
2342 * \param ctx Context for the callback
2343 * \param p Buffer to write to,
2344 * must be updated to point right after the cookie
2345 * \param end Pointer to one past the end of the output buffer
2346 * \param info Client ID info that was passed to
2347 * \c mbedtls_ssl_set_client_transport_id()
2348 * \param ilen Length of info in bytes
2349 *
2350 * \return The callback must return 0 on success,
2351 * or a negative error code.
2352 */
2353 typedef int mbedtls_ssl_cookie_write_t( void *ctx,
2354 unsigned char **p, unsigned char *end,
2355 const unsigned char *info, size_t ilen );
2356
2357 /**
2358 * \brief Callback type: verify a cookie
2359 *
2360 * \param ctx Context for the callback
2361 * \param cookie Cookie to verify
2362 * \param clen Length of cookie
2363 * \param info Client ID info that was passed to
2364 * \c mbedtls_ssl_set_client_transport_id()
2365 * \param ilen Length of info in bytes
2366 *
2367 * \return The callback must return 0 if cookie is valid,
2368 * or a negative error code.
2369 */
2370 typedef int mbedtls_ssl_cookie_check_t( void *ctx,
2371 const unsigned char *cookie, size_t clen,
2372 const unsigned char *info, size_t ilen );
2373
2374 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
2375 /**
2376 * \brief Register callbacks for DTLS cookies
2377 * (Server only. DTLS only.)
2378 *
2379 * Default: dummy callbacks that fail, in order to force you to
2380 * register working callbacks (and initialize their context).
2381 *
2382 * To disable HelloVerifyRequest, register NULL callbacks.
2383 *
2384 * \warning Disabling hello verification allows your server to be used
2385 * for amplification in DoS attacks against other hosts.
2386 * Only disable if you known this can't happen in your
2387 * particular environment.
2388 *
2389 * \note See comments on \c mbedtls_ssl_handshake() about handling
2390 * the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected
2391 * on the first handshake attempt when this is enabled.
2392 *
2393 * \note This is also necessary to handle client reconnection from
2394 * the same port as described in RFC 6347 section 4.2.8 (only
2395 * the variant with cookies is supported currently). See
2396 * comments on \c mbedtls_ssl_read() for details.
2397 *
2398 * \param conf SSL configuration
2399 * \param f_cookie_write Cookie write callback
2400 * \param f_cookie_check Cookie check callback
2401 * \param p_cookie Context for both callbacks
2402 */
2403 void mbedtls_ssl_conf_dtls_cookies( mbedtls_ssl_config *conf,
2404 mbedtls_ssl_cookie_write_t *f_cookie_write,
2405 mbedtls_ssl_cookie_check_t *f_cookie_check,
2406 void *p_cookie );
2407
2408 /**
2409 * \brief Set client's transport-level identification info.
2410 * (Server only. DTLS only.)
2411 *
2412 * This is usually the IP address (and port), but could be
2413 * anything identify the client depending on the underlying
2414 * network stack. Used for HelloVerifyRequest with DTLS.
2415 * This is *not* used to route the actual packets.
2416 *
2417 * \param ssl SSL context
2418 * \param info Transport-level info identifying the client (eg IP + port)
2419 * \param ilen Length of info in bytes
2420 *
2421 * \note An internal copy is made, so the info buffer can be reused.
2422 *
2423 * \return 0 on success,
2424 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client,
2425 * MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory.
2426 */
2427 int mbedtls_ssl_set_client_transport_id( mbedtls_ssl_context *ssl,
2428 const unsigned char *info,
2429 size_t ilen );
2430
2431 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
2432
2433 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
2434 /**
2435 * \brief Enable or disable anti-replay protection for DTLS.
2436 * (DTLS only, no effect on TLS.)
2437 * Default: enabled.
2438 *
2439 * \param conf SSL configuration
2440 * \param mode MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED.
2441 *
2442 * \warning Disabling this is a security risk unless the application
2443 * protocol handles duplicated packets in a safe way. You
2444 * should not disable this without careful consideration.
2445 * However, if your application already detects duplicated
2446 * packets and needs information about them to adjust its
2447 * transmission strategy, then you'll want to disable this.
2448 */
2449 void mbedtls_ssl_conf_dtls_anti_replay( mbedtls_ssl_config *conf, char mode );
2450 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
2451
2452 /**
2453 * \brief Set a limit on the number of records with a bad MAC
2454 * before terminating the connection.
2455 * (DTLS only, no effect on TLS.)
2456 * Default: 0 (disabled).
2457 *
2458 * \param conf SSL configuration
2459 * \param limit Limit, or 0 to disable.
2460 *
2461 * \note If the limit is N, then the connection is terminated when
2462 * the Nth non-authentic record is seen.
2463 *
2464 * \note Records with an invalid header are not counted, only the
2465 * ones going through the authentication-decryption phase.
2466 *
2467 * \note This is a security trade-off related to the fact that it's
2468 * often relatively easy for an active attacker ot inject UDP
2469 * datagrams. On one hand, setting a low limit here makes it
2470 * easier for such an attacker to forcibly terminated a
2471 * connection. On the other hand, a high limit or no limit
2472 * might make us waste resources checking authentication on
2473 * many bogus packets.
2474 */
2475 void mbedtls_ssl_conf_dtls_badmac_limit( mbedtls_ssl_config *conf, unsigned limit );
2476
2477 #if defined(MBEDTLS_SSL_PROTO_DTLS)
2478
2479 /**
2480 * \brief Allow or disallow packing of multiple handshake records
2481 * within a single datagram.
2482 *
2483 * \param ssl The SSL context to configure.
2484 * \param allow_packing This determines whether datagram packing may
2485 * be used or not. A value of \c 0 means that every
2486 * record will be sent in a separate datagram; a
2487 * value of \c 1 means that, if space permits,
2488 * multiple handshake messages (including CCS) belonging to
2489 * a single flight may be packed within a single datagram.
2490 *
2491 * \note This is enabled by default and should only be disabled
2492 * for test purposes, or if datagram packing causes
2493 * interoperability issues with peers that don't support it.
2494 *
2495 * \note Allowing datagram packing reduces the network load since
2496 * there's less overhead if multiple messages share the same
2497 * datagram. Also, it increases the handshake efficiency
2498 * since messages belonging to a single datagram will not
2499 * be reordered in transit, and so future message buffering
2500 * or flight retransmission (if no buffering is used) as
2501 * means to deal with reordering are needed less frequently.
2502 *
2503 * \note Application records are not affected by this option and
2504 * are currently always sent in separate datagrams.
2505 *
2506 */
2507 void mbedtls_ssl_set_datagram_packing( mbedtls_ssl_context *ssl,
2508 unsigned allow_packing );
2509
2510 /**
2511 * \brief Set retransmit timeout values for the DTLS handshake.
2512 * (DTLS only, no effect on TLS.)
2513 *
2514 * \param conf SSL configuration
2515 * \param min Initial timeout value in milliseconds.
2516 * Default: 1000 (1 second).
2517 * \param max Maximum timeout value in milliseconds.
2518 * Default: 60000 (60 seconds).
2519 *
2520 * \note Default values are from RFC 6347 section 4.2.4.1.
2521 *
2522 * \note The 'min' value should typically be slightly above the
2523 * expected round-trip time to your peer, plus whatever time
2524 * it takes for the peer to process the message. For example,
2525 * if your RTT is about 600ms and you peer needs up to 1s to
2526 * do the cryptographic operations in the handshake, then you
2527 * should set 'min' slightly above 1600. Lower values of 'min'
2528 * might cause spurious resends which waste network resources,
2529 * while larger value of 'min' will increase overall latency
2530 * on unreliable network links.
2531 *
2532 * \note The more unreliable your network connection is, the larger
2533 * your max / min ratio needs to be in order to achieve
2534 * reliable handshakes.
2535 *
2536 * \note Messages are retransmitted up to log2(ceil(max/min)) times.
2537 * For example, if min = 1s and max = 5s, the retransmit plan
2538 * goes: send ... 1s -> resend ... 2s -> resend ... 4s ->
2539 * resend ... 5s -> give up and return a timeout error.
2540 */
2541 void mbedtls_ssl_conf_handshake_timeout( mbedtls_ssl_config *conf, uint32_t min, uint32_t max );
2542 #endif /* MBEDTLS_SSL_PROTO_DTLS */
2543
2544 #if defined(MBEDTLS_SSL_SRV_C)
2545 /**
2546 * \brief Set the session cache callbacks (server-side only)
2547 * If not set, no session resuming is done (except if session
2548 * tickets are enabled too).
2549 *
2550 * The session cache has the responsibility to check for stale
2551 * entries based on timeout. See RFC 5246 for recommendations.
2552 *
2553 * Warning: session.peer_cert is cleared by the SSL/TLS layer on
2554 * connection shutdown, so do not cache the pointer! Either set
2555 * it to NULL or make a full copy of the certificate.
2556 *
2557 * The get callback is called once during the initial handshake
2558 * to enable session resuming. The get function has the
2559 * following parameters: (void *parameter, mbedtls_ssl_session *session)
2560 * If a valid entry is found, it should fill the master of
2561 * the session object with the cached values and return 0,
2562 * return 1 otherwise. Optionally peer_cert can be set as well
2563 * if it is properly present in cache entry.
2564 *
2565 * The set callback is called once during the initial handshake
2566 * to enable session resuming after the entire handshake has
2567 * been finished. The set function has the following parameters:
2568 * (void *parameter, const mbedtls_ssl_session *session). The function
2569 * should create a cache entry for future retrieval based on
2570 * the data in the session structure and should keep in mind
2571 * that the mbedtls_ssl_session object presented (and all its referenced
2572 * data) is cleared by the SSL/TLS layer when the connection is
2573 * terminated. It is recommended to add metadata to determine if
2574 * an entry is still valid in the future. Return 0 if
2575 * successfully cached, return 1 otherwise.
2576 *
2577 * \param conf SSL configuration
2578 * \param p_cache parmater (context) for both callbacks
2579 * \param f_get_cache session get callback
2580 * \param f_set_cache session set callback
2581 */
2582 void mbedtls_ssl_conf_session_cache( mbedtls_ssl_config *conf,
2583 void *p_cache,
2584 mbedtls_ssl_cache_get_t *f_get_cache,
2585 mbedtls_ssl_cache_set_t *f_set_cache );
2586 #endif /* MBEDTLS_SSL_SRV_C */
2587
2588 #if defined(MBEDTLS_SSL_CLI_C)
2589 /**
2590 * \brief Load a session for session resumption.
2591 *
2592 * Sessions loaded through this call will be considered
2593 * for session resumption in the next handshake.
2594 *
2595 * \note Even if this call succeeds, it is not guaranteed that
2596 * the next handshake will indeed be shortened through the
2597 * use of session resumption: The server is always free
2598 * to reject any attempt for resumption and fall back to
2599 * a full handshake.
2600 *
2601 * \note This function can handle a variety of mechanisms for session
2602 * resumption: For TLS 1.2, both session ID-based resumption and
2603 * ticket-based resumption will be considered. For TLS 1.3,
2604 * once implemented, sessions equate to tickets, and loading
2605 * one or more sessions via this call will lead to their
2606 * corresponding tickets being advertised as resumption PSKs
2607 * by the client.
2608 *
2609 * \note Calling this function multiple times will only be useful
2610 * once TLS 1.3 is supported. For TLS 1.2 connections, this
2611 * function should be called at most once.
2612 *
2613 * \param ssl The SSL context representing the connection which should
2614 * be attempted to be setup using session resumption. This
2615 * must be initialized via mbedtls_ssl_init() and bound to
2616 * an SSL configuration via mbedtls_ssl_setup(), but
2617 * the handshake must not yet have been started.
2618 * \param session The session to be considered for session resumption.
2619 * This must be a session previously exported via
2620 * mbedtls_ssl_get_session(), and potentially serialized and
2621 * deserialized through mbedtls_ssl_session_save() and
2622 * mbedtls_ssl_session_load() in the meantime.
2623 *
2624 * \return \c 0 if successful.
2625 * \return \c MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if the session
2626 * could not be loaded because of an implementation limitation.
2627 * This error is non-fatal, and has no observable effect on
2628 * the SSL context or the session that was attempted to be loaded.
2629 * \return Another negative error code on other kinds of failure.
2630 *
2631 * \sa mbedtls_ssl_get_session()
2632 * \sa mbedtls_ssl_session_load()
2633 */
2634 int mbedtls_ssl_set_session( mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session );
2635 #endif /* MBEDTLS_SSL_CLI_C */
2636
2637 /**
2638 * \brief Load serialized session data into a session structure.
2639 * On client, this can be used for loading saved sessions
2640 * before resuming them with mbedstls_ssl_set_session().
2641 * On server, this can be used for alternative implementations
2642 * of session cache or session tickets.
2643 *
2644 * \warning If a peer certificate chain is associated with the session,
2645 * the serialized state will only contain the peer's
2646 * end-entity certificate and the result of the chain
2647 * verification (unless verification was disabled), but not
2648 * the rest of the chain.
2649 *
2650 * \see mbedtls_ssl_session_save()
2651 * \see mbedtls_ssl_set_session()
2652 *
2653 * \param session The session structure to be populated. It must have been
2654 * initialised with mbedtls_ssl_session_init() but not
2655 * populated yet.
2656 * \param buf The buffer holding the serialized session data. It must be a
2657 * readable buffer of at least \p len bytes.
2658 * \param len The size of the serialized data in bytes.
2659 *
2660 * \return \c 0 if successful.
2661 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
2662 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
2663 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
2664 * was generated in a different version or configuration of
2665 * Mbed TLS.
2666 * \return Another negative value for other kinds of errors (for
2667 * example, unsupported features in the embedded certificate).
2668 */
2669 int mbedtls_ssl_session_load( mbedtls_ssl_session *session,
2670 const unsigned char *buf,
2671 size_t len );
2672
2673 /**
2674 * \brief Save session structure as serialized data in a buffer.
2675 * On client, this can be used for saving session data,
2676 * potentially in non-volatile storage, for resuming later.
2677 * On server, this can be used for alternative implementations
2678 * of session cache or session tickets.
2679 *
2680 * \see mbedtls_ssl_session_load()
2681 *
2682 * \param session The session structure to be saved.
2683 * \param buf The buffer to write the serialized data to. It must be a
2684 * writeable buffer of at least \p len bytes, or may be \c
2685 * NULL if \p len is \c 0.
2686 * \param buf_len The number of bytes available for writing in \p buf.
2687 * \param olen The size in bytes of the data that has been or would have
2688 * been written. It must point to a valid \c size_t.
2689 *
2690 * \note \p olen is updated to the correct value regardless of
2691 * whether \p buf_len was large enough. This makes it possible
2692 * to determine the necessary size by calling this function
2693 * with \p buf set to \c NULL and \p buf_len to \c 0.
2694 *
2695 * \return \c 0 if successful.
2696 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
2697 */
2698 int mbedtls_ssl_session_save( const mbedtls_ssl_session *session,
2699 unsigned char *buf,
2700 size_t buf_len,
2701 size_t *olen );
2702
2703 /**
2704 * \brief Set the list of allowed ciphersuites and the preference
2705 * order. First in the list has the highest preference.
2706 *
2707 * For TLS 1.2, the notion of ciphersuite determines both
2708 * the key exchange mechanism and the suite of symmetric
2709 * algorithms to be used during and after the handshake.
2710 *
2711 * For TLS 1.3 (in development), the notion of ciphersuite
2712 * only determines the suite of symmetric algorithms to be
2713 * used during and after the handshake, while key exchange
2714 * mechanisms are configured separately.
2715 *
2716 * In Mbed TLS, ciphersuites for both TLS 1.2 and TLS 1.3
2717 * are configured via this function. For users of TLS 1.3,
2718 * there will be separate API for the configuration of key
2719 * exchange mechanisms.
2720 *
2721 * The list of ciphersuites passed to this function may
2722 * contain a mixture of TLS 1.2 and TLS 1.3 ciphersuite
2723 * identifiers. This is useful if negotiation of TLS 1.3
2724 * should be attempted, but a fallback to TLS 1.2 would
2725 * be tolerated.
2726 *
2727 * \note By default, the server chooses its preferred
2728 * ciphersuite among those that the client supports. If
2729 * mbedtls_ssl_conf_preference_order() is called to prefer
2730 * the client's preferences, the server instead chooses
2731 * the client's preferred ciphersuite among those that
2732 * the server supports.
2733 *
2734 * \warning The ciphersuites array \p ciphersuites is not copied.
2735 * It must remain valid for the lifetime of the SSL
2736 * configuration \p conf.
2737 *
2738 * \param conf The SSL configuration to modify.
2739 * \param ciphersuites A 0-terminated list of IANA identifiers of supported
2740 * ciphersuites, accessible through \c MBEDTLS_TLS_XXX
2741 * and \c MBEDTLS_TLS1_3_XXX macros defined in
2742 * ssl_ciphersuites.h.
2743 */
2744 void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf,
2745 const int *ciphersuites );
2746
2747 #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
2748 /**
2749 * \brief Set the supported key exchange modes for TLS 1.3 connections.
2750 *
2751 * In contrast to TLS 1.2, the ciphersuite concept in TLS 1.3 does not
2752 * include the choice of key exchange mechanism. It is therefore not
2753 * covered by the API mbedtls_ssl_conf_ciphersuites(). See the
2754 * documentation of mbedtls_ssl_conf_ciphersuites() for more
2755 * information on the ciphersuite concept in TLS 1.2 and TLS 1.3.
2756 *
2757 * The present function is specific to TLS 1.3 and allows users to
2758 * configure the set of supported key exchange mechanisms in TLS 1.3.
2759 *
2760 * \param conf The SSL configuration the change should apply to.
2761 * \param kex_modes A bitwise combination of one or more of the following:
2762 * - MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK
2763 * This flag enables pure-PSK key exchanges.
2764 * - MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_EPHEMERAL
2765 * This flag enables combined PSK-ephemeral key exchanges.
2766 * - MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL
2767 * This flag enables pure-ephemeral key exchanges.
2768 * For convenience, the following pre-defined macros are
2769 * available for combinations of the above:
2770 * - MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_ALL
2771 * Includes all of pure-PSK, PSK-ephemeral and pure-ephemeral.
2772 * - MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_PSK_ALL
2773 * Includes both pure-PSK and combined PSK-ephemeral
2774 * key exchanges, but excludes pure-ephemeral key exchanges.
2775 * - MBEDTLS_SSL_TLS13_KEY_EXCHANGE_MODE_EPHEMERAL_ALL
2776 * Includes both pure-ephemeral and combined PSK-ephemeral
2777 * key exchanges.
2778 *
2779 * \note If a PSK-based key exchange mode shall be supported, applications
2780 * must also use the APIs mbedtls_ssl_conf_psk() or
2781 * mbedtls_ssl_conf_psk_cb() or mbedtls_ssl_conf_psk_opaque()
2782 * to configure the PSKs to be used.
2783 *
2784 * \note If a pure-ephemeral key exchange mode shall be supported,
2785 * server-side applications must also provide a certificate via
2786 * mbedtls_ssl_conf_own_cert().
2787 *
2788 */
2789
2790 void mbedtls_ssl_conf_tls13_key_exchange_modes( mbedtls_ssl_config* conf,
2791 const int kex_modes );
2792 #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
2793
2794 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
2795 #define MBEDTLS_SSL_UNEXPECTED_CID_IGNORE 0
2796 #define MBEDTLS_SSL_UNEXPECTED_CID_FAIL 1
2797 /**
2798 * \brief Specify the length of Connection IDs for incoming
2799 * encrypted DTLS records, as well as the behaviour
2800 * on unexpected CIDs.
2801 *
2802 * By default, the CID length is set to \c 0,
2803 * and unexpected CIDs are silently ignored.
2804 *
2805 * \param conf The SSL configuration to modify.
2806 * \param len The length in Bytes of the CID fields in encrypted
2807 * DTLS records using the CID mechanism. This must
2808 * not be larger than #MBEDTLS_SSL_CID_OUT_LEN_MAX.
2809 * \param ignore_other_cids This determines the stack's behaviour when
2810 * receiving a record with an unexpected CID.
2811 * Possible values are:
2812 * - #MBEDTLS_SSL_UNEXPECTED_CID_IGNORE
2813 * In this case, the record is silently ignored.
2814 * - #MBEDTLS_SSL_UNEXPECTED_CID_FAIL
2815 * In this case, the stack fails with the specific
2816 * error code #MBEDTLS_ERR_SSL_UNEXPECTED_CID.
2817 *
2818 * \note The CID specification allows implementations to either
2819 * use a common length for all incoming connection IDs or
2820 * allow variable-length incoming IDs. Mbed TLS currently
2821 * requires a common length for all connections sharing the
2822 * same SSL configuration; this allows simpler parsing of
2823 * record headers.
2824 *
2825 * \return \c 0 on success.
2826 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if \p own_cid_len
2827 * is too large.
2828 */
2829 int mbedtls_ssl_conf_cid( mbedtls_ssl_config *conf, size_t len,
2830 int ignore_other_cids );
2831 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
2832
2833 #if defined(MBEDTLS_X509_CRT_PARSE_C)
2834 /**
2835 * \brief Set the X.509 security profile used for verification
2836 *
2837 * \note The restrictions are enforced for all certificates in the
2838 * chain. However, signatures in the handshake are not covered
2839 * by this setting but by \b mbedtls_ssl_conf_sig_hashes().
2840 *
2841 * \param conf SSL configuration
2842 * \param profile Profile to use
2843 */
2844 void mbedtls_ssl_conf_cert_profile( mbedtls_ssl_config *conf,
2845 const mbedtls_x509_crt_profile *profile );
2846
2847 /**
2848 * \brief Set the data required to verify peer certificate
2849 *
2850 * \note See \c mbedtls_x509_crt_verify() for notes regarding the
2851 * parameters ca_chain (maps to trust_ca for that function)
2852 * and ca_crl.
2853 *
2854 * \param conf SSL configuration
2855 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
2856 * \param ca_crl trusted CA CRLs
2857 */
2858 void mbedtls_ssl_conf_ca_chain( mbedtls_ssl_config *conf,
2859 mbedtls_x509_crt *ca_chain,
2860 mbedtls_x509_crl *ca_crl );
2861
2862 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
2863 /**
2864 * \brief Set the trusted certificate callback.
2865 *
2866 * This API allows to register the set of trusted certificates
2867 * through a callback, instead of a linked list as configured
2868 * by mbedtls_ssl_conf_ca_chain().
2869 *
2870 * This is useful for example in contexts where a large number
2871 * of CAs are used, and the inefficiency of maintaining them
2872 * in a linked list cannot be tolerated. It is also useful when
2873 * the set of trusted CAs needs to be modified frequently.
2874 *
2875 * See the documentation of `mbedtls_x509_crt_ca_cb_t` for
2876 * more information.
2877 *
2878 * \param conf The SSL configuration to register the callback with.
2879 * \param f_ca_cb The trusted certificate callback to use when verifying
2880 * certificate chains.
2881 * \param p_ca_cb The context to be passed to \p f_ca_cb (for example,
2882 * a reference to a trusted CA database).
2883 *
2884 * \note This API is incompatible with mbedtls_ssl_conf_ca_chain():
2885 * Any call to this function overwrites the values set through
2886 * earlier calls to mbedtls_ssl_conf_ca_chain() or
2887 * mbedtls_ssl_conf_ca_cb().
2888 *
2889 * \note This API is incompatible with CA indication in
2890 * CertificateRequest messages: A server-side SSL context which
2891 * is bound to an SSL configuration that uses a CA callback
2892 * configured via mbedtls_ssl_conf_ca_cb(), and which requires
2893 * client authentication, will send an empty CA list in the
2894 * corresponding CertificateRequest message.
2895 *
2896 * \note This API is incompatible with mbedtls_ssl_set_hs_ca_chain():
2897 * If an SSL context is bound to an SSL configuration which uses
2898 * CA callbacks configured via mbedtls_ssl_conf_ca_cb(), then
2899 * calls to mbedtls_ssl_set_hs_ca_chain() have no effect.
2900 *
2901 * \note The use of this API disables the use of restartable ECC
2902 * during X.509 CRT signature verification (but doesn't affect
2903 * other uses).
2904 *
2905 * \warning This API is incompatible with the use of CRLs. Any call to
2906 * mbedtls_ssl_conf_ca_cb() unsets CRLs configured through
2907 * earlier calls to mbedtls_ssl_conf_ca_chain().
2908 *
2909 * \warning In multi-threaded environments, the callback \p f_ca_cb
2910 * must be thread-safe, and it is the user's responsibility
2911 * to guarantee this (for example through a mutex
2912 * contained in the callback context pointed to by \p p_ca_cb).
2913 */
2914 void mbedtls_ssl_conf_ca_cb( mbedtls_ssl_config *conf,
2915 mbedtls_x509_crt_ca_cb_t f_ca_cb,
2916 void *p_ca_cb );
2917 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
2918
2919 /**
2920 * \brief Set own certificate chain and private key
2921 *
2922 * \note own_cert should contain in order from the bottom up your
2923 * certificate chain. The top certificate (self-signed)
2924 * can be omitted.
2925 *
2926 * \note On server, this function can be called multiple times to
2927 * provision more than one cert/key pair (eg one ECDSA, one
2928 * RSA with SHA-256, one RSA with SHA-1). An adequate
2929 * certificate will be selected according to the client's
2930 * advertised capabilities. In case multiple certificates are
2931 * adequate, preference is given to the one set by the first
2932 * call to this function, then second, etc.
2933 *
2934 * \note On client, only the first call has any effect. That is,
2935 * only one client certificate can be provisioned. The
2936 * server's preferences in its CertficateRequest message will
2937 * be ignored and our only cert will be sent regardless of
2938 * whether it matches those preferences - the server can then
2939 * decide what it wants to do with it.
2940 *
2941 * \note The provided \p pk_key needs to match the public key in the
2942 * first certificate in \p own_cert, or all handshakes using
2943 * that certificate will fail. It is your responsibility
2944 * to ensure that; this function will not perform any check.
2945 * You may use mbedtls_pk_check_pair() in order to perform
2946 * this check yourself, but be aware that this function can
2947 * be computationally expensive on some key types.
2948 *
2949 * \param conf SSL configuration
2950 * \param own_cert own public certificate chain
2951 * \param pk_key own private key
2952 *
2953 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
2954 */
2955 int mbedtls_ssl_conf_own_cert( mbedtls_ssl_config *conf,
2956 mbedtls_x509_crt *own_cert,
2957 mbedtls_pk_context *pk_key );
2958 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2959
2960 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
2961 /**
2962 * \brief Configure pre-shared keys (PSKs) and their
2963 * identities to be used in PSK-based ciphersuites.
2964 *
2965 * Only one PSK can be registered, through either
2966 * mbedtls_ssl_conf_psk() or mbedtls_ssl_conf_psk_opaque().
2967 * If you attempt to register more than one PSK, this function
2968 * fails, though this may change in future versions, which
2969 * may add support for multiple PSKs.
2970 *
2971 * \note This is mainly useful for clients. Servers will usually
2972 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
2973 *
2974 * \note A PSK set by \c mbedtls_ssl_set_hs_psk() in the PSK callback
2975 * takes precedence over a PSK configured by this function.
2976 *
2977 * \param conf The SSL configuration to register the PSK with.
2978 * \param psk The pointer to the pre-shared key to use.
2979 * \param psk_len The length of the pre-shared key in bytes.
2980 * \param psk_identity The pointer to the pre-shared key identity.
2981 * \param psk_identity_len The length of the pre-shared key identity
2982 * in bytes.
2983 *
2984 * \note The PSK and its identity are copied internally and
2985 * hence need not be preserved by the caller for the lifetime
2986 * of the SSL configuration.
2987 *
2988 * \return \c 0 if successful.
2989 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no more PSKs
2990 * can be configured. In this case, the old PSK(s) remain intact.
2991 * \return Another negative error code on other kinds of failure.
2992 */
2993 int mbedtls_ssl_conf_psk( mbedtls_ssl_config *conf,
2994 const unsigned char *psk, size_t psk_len,
2995 const unsigned char *psk_identity, size_t psk_identity_len );
2996
2997 #if defined(MBEDTLS_USE_PSA_CRYPTO)
2998 /**
2999 * \brief Configure one or more opaque pre-shared keys (PSKs) and
3000 * their identities to be used in PSK-based ciphersuites.
3001 *
3002 * Only one PSK can be registered, through either
3003 * mbedtls_ssl_conf_psk() or mbedtls_ssl_conf_psk_opaque().
3004 * If you attempt to register more than one PSK, this function
3005 * fails, though this may change in future versions, which
3006 * may add support for multiple PSKs.
3007 *
3008 * \note This is mainly useful for clients. Servers will usually
3009 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
3010 *
3011 * \note An opaque PSK set by \c mbedtls_ssl_set_hs_psk_opaque() in
3012 * the PSK callback takes precedence over an opaque PSK
3013 * configured by this function.
3014 *
3015 * \param conf The SSL configuration to register the PSK with.
3016 * \param psk The identifier of the key slot holding the PSK.
3017 * Until \p conf is destroyed or this function is successfully
3018 * called again, the key slot \p psk must be populated with a
3019 * key of type PSA_ALG_CATEGORY_KEY_DERIVATION whose policy
3020 * allows its use for the key derivation algorithm applied
3021 * in the handshake.
3022 * \param psk_identity The pointer to the pre-shared key identity.
3023 * \param psk_identity_len The length of the pre-shared key identity
3024 * in bytes.
3025 *
3026 * \note The PSK identity hint is copied internally and hence need
3027 * not be preserved by the caller for the lifetime of the
3028 * SSL configuration.
3029 *
3030 * \return \c 0 if successful.
3031 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no more PSKs
3032 * can be configured. In this case, the old PSK(s) remain intact.
3033 * \return Another negative error code on other kinds of failure.
3034 */
3035 int mbedtls_ssl_conf_psk_opaque( mbedtls_ssl_config *conf,
3036 psa_key_id_t psk,
3037 const unsigned char *psk_identity,
3038 size_t psk_identity_len );
3039 #endif /* MBEDTLS_USE_PSA_CRYPTO */
3040
3041 /**
3042 * \brief Set the pre-shared Key (PSK) for the current handshake.
3043 *
3044 * \note This should only be called inside the PSK callback,
3045 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
3046 *
3047 * \note A PSK set by this function takes precedence over a PSK
3048 * configured by \c mbedtls_ssl_conf_psk().
3049 *
3050 * \param ssl The SSL context to configure a PSK for.
3051 * \param psk The pointer to the pre-shared key.
3052 * \param psk_len The length of the pre-shared key in bytes.
3053 *
3054 * \return \c 0 if successful.
3055 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
3056 */
3057 int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl,
3058 const unsigned char *psk, size_t psk_len );
3059
3060 #if defined(MBEDTLS_USE_PSA_CRYPTO)
3061 /**
3062 * \brief Set an opaque pre-shared Key (PSK) for the current handshake.
3063 *
3064 * \note This should only be called inside the PSK callback,
3065 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
3066 *
3067 * \note An opaque PSK set by this function takes precedence over an
3068 * opaque PSK configured by \c mbedtls_ssl_conf_psk_opaque().
3069 *
3070 * \param ssl The SSL context to configure a PSK for.
3071 * \param psk The identifier of the key slot holding the PSK.
3072 * For the duration of the current handshake, the key slot
3073 * must be populated with a key of type
3074 * PSA_ALG_CATEGORY_KEY_DERIVATION whose policy allows its
3075 * use for the key derivation algorithm
3076 * applied in the handshake.
3077 *
3078 * \return \c 0 if successful.
3079 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
3080 */
3081 int mbedtls_ssl_set_hs_psk_opaque( mbedtls_ssl_context *ssl,
3082 psa_key_id_t psk );
3083 #endif /* MBEDTLS_USE_PSA_CRYPTO */
3084
3085 /**
3086 * \brief Set the PSK callback (server-side only).
3087 *
3088 * If set, the PSK callback is called for each
3089 * handshake where a PSK-based ciphersuite was negotiated.
3090 * The caller provides the identity received and wants to
3091 * receive the actual PSK data and length.
3092 *
3093 * The callback has the following parameters:
3094 * - \c void*: The opaque pointer \p p_psk.
3095 * - \c mbedtls_ssl_context*: The SSL context to which
3096 * the operation applies.
3097 * - \c const unsigned char*: The PSK identity
3098 * selected by the client.
3099 * - \c size_t: The length of the PSK identity
3100 * selected by the client.
3101 *
3102 * If a valid PSK identity is found, the callback should use
3103 * \c mbedtls_ssl_set_hs_psk() or
3104 * \c mbedtls_ssl_set_hs_psk_opaque()
3105 * on the SSL context to set the correct PSK and return \c 0.
3106 * Any other return value will result in a denied PSK identity.
3107 *
3108 * \note A dynamic PSK (i.e. set by the PSK callback) takes
3109 * precedence over a static PSK (i.e. set by
3110 * \c mbedtls_ssl_conf_psk() or
3111 * \c mbedtls_ssl_conf_psk_opaque()).
3112 * This means that if you set a PSK callback using this
3113 * function, you don't need to set a PSK using
3114 * \c mbedtls_ssl_conf_psk() or
3115 * \c mbedtls_ssl_conf_psk_opaque()).
3116 *
3117 * \param conf The SSL configuration to register the callback with.
3118 * \param f_psk The callback for selecting and setting the PSK based
3119 * in the PSK identity chosen by the client.
3120 * \param p_psk A pointer to an opaque structure to be passed to
3121 * the callback, for example a PSK store.
3122 */
3123 void mbedtls_ssl_conf_psk_cb( mbedtls_ssl_config *conf,
3124 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *,
3125 size_t),
3126 void *p_psk );
3127 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
3128
3129 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
3130 /**
3131 * \brief Set the Diffie-Hellman public P and G values
3132 * from big-endian binary presentations.
3133 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN)
3134 *
3135 * \param conf SSL configuration
3136 * \param dhm_P Diffie-Hellman-Merkle modulus in big-endian binary form
3137 * \param P_len Length of DHM modulus
3138 * \param dhm_G Diffie-Hellman-Merkle generator in big-endian binary form
3139 * \param G_len Length of DHM generator
3140 *
3141 * \return 0 if successful
3142 */
3143 int mbedtls_ssl_conf_dh_param_bin( mbedtls_ssl_config *conf,
3144 const unsigned char *dhm_P, size_t P_len,
3145 const unsigned char *dhm_G, size_t G_len );
3146
3147 /**
3148 * \brief Set the Diffie-Hellman public P and G values,
3149 * read from existing context (server-side only)
3150 *
3151 * \param conf SSL configuration
3152 * \param dhm_ctx Diffie-Hellman-Merkle context
3153 *
3154 * \return 0 if successful
3155 */
3156 int mbedtls_ssl_conf_dh_param_ctx( mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx );
3157 #endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */
3158
3159 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
3160 /**
3161 * \brief Set the minimum length for Diffie-Hellman parameters.
3162 * (Client-side only.)
3163 * (Default: 1024 bits.)
3164 *
3165 * \param conf SSL configuration
3166 * \param bitlen Minimum bit length of the DHM prime
3167 */
3168 void mbedtls_ssl_conf_dhm_min_bitlen( mbedtls_ssl_config *conf,
3169 unsigned int bitlen );
3170 #endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */
3171
3172 #if defined(MBEDTLS_ECP_C)
3173 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
3174 /**
3175 * \brief Set the allowed curves in order of preference.
3176 *
3177 * On server: this only affects selection of the ECDHE curve;
3178 * the curves used for ECDH and ECDSA are determined by the
3179 * list of available certificates instead.
3180 *
3181 * On client: this affects the list of curves offered for any
3182 * use. The server can override our preference order.
3183 *
3184 * Both sides: limits the set of curves accepted for use in
3185 * ECDHE and in the peer's end-entity certificate.
3186 *
3187 * \deprecated Superseeded by mbedtls_ssl_conf_groups().
3188 *
3189 * \note This has no influence on which curves are allowed inside the
3190 * certificate chains, see \c mbedtls_ssl_conf_cert_profile()
3191 * for that. For the end-entity certificate however, the key
3192 * will be accepted only if it is allowed both by this list
3193 * and by the cert profile.
3194 *
3195 * \note This list should be ordered by decreasing preference
3196 * (preferred curve first).
3197 *
3198 * \note The default list is the same set of curves that
3199 * #mbedtls_x509_crt_profile_default allows, plus
3200 * ECDHE-only curves selected according to the same criteria.
3201 * The order favors curves with the lowest resource usage.
3202 *
3203 * \note New minor versions of Mbed TLS may extend this list,
3204 * for example if new curves are added to the library.
3205 * New minor versions of Mbed TLS will not remove items
3206 * from this list unless serious security concerns require it.
3207 * New minor versions of Mbed TLS may change the order in
3208 * keeping with the general principle of favoring the lowest
3209 * resource usage.
3210 *
3211 * \param conf SSL configuration
3212 * \param curves Ordered list of allowed curves,
3213 * terminated by MBEDTLS_ECP_DP_NONE.
3214 */
3215 void MBEDTLS_DEPRECATED mbedtls_ssl_conf_curves( mbedtls_ssl_config *conf,
3216 const mbedtls_ecp_group_id *curves );
3217 #endif /* MBEDTLS_DEPRECATED_REMOVED */
3218 #endif /* MBEDTLS_ECP_C */
3219
3220 /**
3221 * \brief Set the allowed groups in order of preference.
3222 *
3223 * On server: This only affects the choice of key agreement mechanism
3224 *
3225 * On client: this affects the list of groups offered for any
3226 * use. The server can override our preference order.
3227 *
3228 * Both sides: limits the set of groups accepted for use in
3229 * key sharing.
3230 *
3231 * \note This function replaces the deprecated mbedtls_ssl_conf_curves(),
3232 * which only allows ECP curves to be configured.
3233 *
3234 * \note The most recent invocation of either mbedtls_ssl_conf_curves()
3235 * or mbedtls_ssl_conf_groups() nullifies all previous invocations
3236 * of both.
3237 *
3238 * \note This list should be ordered by decreasing preference
3239 * (preferred group first).
3240 *
3241 * \note When this function is not called, a default list is used,
3242 * consisting of all supported curves at 255 bits and above,
3243 * and all supported finite fields at 2048 bits and above.
3244 * The order favors groups with the lowest resource usage.
3245 *
3246 * \note New minor versions of Mbed TLS will not remove items
3247 * from the default list unless serious security concerns require it.
3248 * New minor versions of Mbed TLS may change the order in
3249 * keeping with the general principle of favoring the lowest
3250 * resource usage.
3251 *
3252 * \param conf SSL configuration
3253 * \param groups List of allowed groups ordered by preference, terminated by 0.
3254 * Must contain valid IANA NamedGroup IDs (provided via either an integer
3255 * or using MBEDTLS_TLS13_NAMED_GROUP_XXX macros).
3256 */
3257 void mbedtls_ssl_conf_groups( mbedtls_ssl_config *conf,
3258 const uint16_t *groups );
3259
3260 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
3261 /**
3262 * \brief Set the allowed hashes for signatures during the handshake.
3263 *
3264 * \note This only affects which hashes are offered and can be used
3265 * for signatures during the handshake. Hashes for message
3266 * authentication and the TLS PRF are controlled by the
3267 * ciphersuite, see \c mbedtls_ssl_conf_ciphersuites(). Hashes
3268 * used for certificate signature are controlled by the
3269 * verification profile, see \c mbedtls_ssl_conf_cert_profile().
3270 *
3271 * \note This list should be ordered by decreasing preference
3272 * (preferred hash first).
3273 *
3274 * \note By default, all supported hashes whose length is at least
3275 * 256 bits are allowed. This is the same set as the default
3276 * for certificate verification
3277 * (#mbedtls_x509_crt_profile_default).
3278 * The preference order is currently unspecified and may
3279 * change in future versions.
3280 *
3281 * \note New minor versions of Mbed TLS may extend this list,
3282 * for example if new curves are added to the library.
3283 * New minor versions of Mbed TLS will not remove items
3284 * from this list unless serious security concerns require it.
3285 *
3286 * \param conf SSL configuration
3287 * \param hashes Ordered list of allowed signature hashes,
3288 * terminated by \c MBEDTLS_MD_NONE.
3289 */
3290 void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf,
3291 const int *hashes );
3292
3293 #if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
3294 /**
3295 * \brief Configure allowed signature algorithms for use in TLS 1.3
3296 *
3297 * \param conf The SSL configuration to use.
3298 * \param sig_algs List of allowed IANA values for TLS 1.3 signature algorithms,
3299 * terminated by \c MBEDTLS_TLS13_SIG_NONE. The list must remain
3300 * available throughout the lifetime of the conf object. Supported
3301 * values are available as \c MBEDTLS_TLS13_SIG_XXXX
3302 */
3303 void mbedtls_ssl_conf_sig_algs( mbedtls_ssl_config *conf,
3304 const uint16_t* sig_algs );
3305 #endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
3306 #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
3307
3308 #if defined(MBEDTLS_X509_CRT_PARSE_C)
3309 /**
3310 * \brief Set or reset the hostname to check against the received
3311 * server certificate. It sets the ServerName TLS extension,
3312 * too, if that extension is enabled. (client-side only)
3313 *
3314 * \param ssl SSL context
3315 * \param hostname the server hostname, may be NULL to clear hostname
3316
3317 * \note Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN.
3318 *
3319 * \return 0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on
3320 * allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on
3321 * too long input hostname.
3322 *
3323 * Hostname set to the one provided on success (cleared
3324 * when NULL). On allocation failure hostname is cleared.
3325 * On too long input failure, old hostname is unchanged.
3326 */
3327 int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname );
3328 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3329
3330 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
3331 /**
3332 * \brief Set own certificate and key for the current handshake
3333 *
3334 * \note Same as \c mbedtls_ssl_conf_own_cert() but for use within
3335 * the SNI callback.
3336 *
3337 * \param ssl SSL context
3338 * \param own_cert own public certificate chain
3339 * \param pk_key own private key
3340 *
3341 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
3342 */
3343 int mbedtls_ssl_set_hs_own_cert( mbedtls_ssl_context *ssl,
3344 mbedtls_x509_crt *own_cert,
3345 mbedtls_pk_context *pk_key );
3346
3347 /**
3348 * \brief Set the data required to verify peer certificate for the
3349 * current handshake
3350 *
3351 * \note Same as \c mbedtls_ssl_conf_ca_chain() but for use within
3352 * the SNI callback.
3353 *
3354 * \param ssl SSL context
3355 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
3356 * \param ca_crl trusted CA CRLs
3357 */
3358 void mbedtls_ssl_set_hs_ca_chain( mbedtls_ssl_context *ssl,
3359 mbedtls_x509_crt *ca_chain,
3360 mbedtls_x509_crl *ca_crl );
3361
3362 /**
3363 * \brief Set authmode for the current handshake.
3364 *
3365 * \note Same as \c mbedtls_ssl_conf_authmode() but for use within
3366 * the SNI callback.
3367 *
3368 * \param ssl SSL context
3369 * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or
3370 * MBEDTLS_SSL_VERIFY_REQUIRED
3371 */
3372 void mbedtls_ssl_set_hs_authmode( mbedtls_ssl_context *ssl,
3373 int authmode );
3374
3375 /**
3376 * \brief Set server side ServerName TLS extension callback
3377 * (optional, server-side only).
3378 *
3379 * If set, the ServerName callback is called whenever the
3380 * server receives a ServerName TLS extension from the client
3381 * during a handshake. The ServerName callback has the
3382 * following parameters: (void *parameter, mbedtls_ssl_context *ssl,
3383 * const unsigned char *hostname, size_t len). If a suitable
3384 * certificate is found, the callback must set the
3385 * certificate(s) and key(s) to use with \c
3386 * mbedtls_ssl_set_hs_own_cert() (can be called repeatedly),
3387 * and may optionally adjust the CA and associated CRL with \c
3388 * mbedtls_ssl_set_hs_ca_chain() as well as the client
3389 * authentication mode with \c mbedtls_ssl_set_hs_authmode(),
3390 * then must return 0. If no matching name is found, the
3391 * callback must either set a default cert, or
3392 * return non-zero to abort the handshake at this point.
3393 *
3394 * \param conf SSL configuration
3395 * \param f_sni verification function
3396 * \param p_sni verification parameter
3397 */
3398 void mbedtls_ssl_conf_sni( mbedtls_ssl_config *conf,
3399 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *,
3400 size_t),
3401 void *p_sni );
3402 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
3403
3404 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
3405 /**
3406 * \brief Set the EC J-PAKE password for current handshake.
3407 *
3408 * \note An internal copy is made, and destroyed as soon as the
3409 * handshake is completed, or when the SSL context is reset or
3410 * freed.
3411 *
3412 * \note The SSL context needs to be already set up. The right place
3413 * to call this function is between \c mbedtls_ssl_setup() or
3414 * \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake().
3415 *
3416 * \param ssl SSL context
3417 * \param pw EC J-PAKE password (pre-shared secret)
3418 * \param pw_len length of pw in bytes
3419 *
3420 * \return 0 on success, or a negative error code.
3421 */
3422 int mbedtls_ssl_set_hs_ecjpake_password( mbedtls_ssl_context *ssl,
3423 const unsigned char *pw,
3424 size_t pw_len );
3425 #endif /*MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
3426
3427 #if defined(MBEDTLS_SSL_ALPN)
3428 /**
3429 * \brief Set the supported Application Layer Protocols.
3430 *
3431 * \param conf SSL configuration
3432 * \param protos Pointer to a NULL-terminated list of supported protocols,
3433 * in decreasing preference order. The pointer to the list is
3434 * recorded by the library for later reference as required, so
3435 * the lifetime of the table must be atleast as long as the
3436 * lifetime of the SSL configuration structure.
3437 *
3438 * \return 0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA.
3439 */
3440 int mbedtls_ssl_conf_alpn_protocols( mbedtls_ssl_config *conf, const char **protos );
3441
3442 /**
3443 * \brief Get the name of the negotiated Application Layer Protocol.
3444 * This function should be called after the handshake is
3445 * completed.
3446 *
3447 * \param ssl SSL context
3448 *
3449 * \return Protcol name, or NULL if no protocol was negotiated.
3450 */
3451 const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl );
3452 #endif /* MBEDTLS_SSL_ALPN */
3453
3454 #if defined(MBEDTLS_SSL_DTLS_SRTP)
3455 #if defined(MBEDTLS_DEBUG_C)
mbedtls_ssl_get_srtp_profile_as_string(mbedtls_ssl_srtp_profile profile)3456 static inline const char *mbedtls_ssl_get_srtp_profile_as_string( mbedtls_ssl_srtp_profile profile )
3457 {
3458 switch( profile )
3459 {
3460 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80:
3461 return( "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80" );
3462 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32:
3463 return( "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" );
3464 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80:
3465 return( "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80" );
3466 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32:
3467 return( "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32" );
3468 default: break;
3469 }
3470 return( "" );
3471 }
3472 #endif /* MBEDTLS_DEBUG_C */
3473 /**
3474 * \brief Manage support for mki(master key id) value
3475 * in use_srtp extension.
3476 * MKI is an optional part of SRTP used for key management
3477 * and re-keying. See RFC3711 section 3.1 for details.
3478 * The default value is
3479 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED.
3480 *
3481 * \param conf The SSL configuration to manage mki support.
3482 * \param support_mki_value Enable or disable mki usage. Values are
3483 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED
3484 * or #MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED.
3485 */
3486 void mbedtls_ssl_conf_srtp_mki_value_supported( mbedtls_ssl_config *conf,
3487 int support_mki_value );
3488
3489 /**
3490 * \brief Set the supported DTLS-SRTP protection profiles.
3491 *
3492 * \param conf SSL configuration
3493 * \param profiles Pointer to a List of MBEDTLS_TLS_SRTP_UNSET terminated
3494 * supported protection profiles
3495 * in decreasing preference order.
3496 * The pointer to the list is recorded by the library
3497 * for later reference as required, so the lifetime
3498 * of the table must be at least as long as the lifetime
3499 * of the SSL configuration structure.
3500 * The list must not hold more than
3501 * MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH elements
3502 * (excluding the terminating MBEDTLS_TLS_SRTP_UNSET).
3503 *
3504 * \return 0 on success
3505 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA when the list of
3506 * protection profiles is incorrect.
3507 */
3508 int mbedtls_ssl_conf_dtls_srtp_protection_profiles
3509 ( mbedtls_ssl_config *conf,
3510 const mbedtls_ssl_srtp_profile *profiles );
3511
3512 /**
3513 * \brief Set the mki_value for the current DTLS-SRTP session.
3514 *
3515 * \param ssl SSL context to use.
3516 * \param mki_value The MKI value to set.
3517 * \param mki_len The length of the MKI value.
3518 *
3519 * \note This function is relevant on client side only.
3520 * The server discovers the mki value during handshake.
3521 * A mki value set on server side using this function
3522 * is ignored.
3523 *
3524 * \return 0 on success
3525 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA
3526 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE
3527 */
3528 int mbedtls_ssl_dtls_srtp_set_mki_value( mbedtls_ssl_context *ssl,
3529 unsigned char *mki_value,
3530 uint16_t mki_len );
3531 /**
3532 * \brief Get the negotiated DTLS-SRTP informations:
3533 * Protection profile and MKI value.
3534 *
3535 * \warning This function must be called after the handshake is
3536 * completed. The value returned by this function must
3537 * not be trusted or acted upon before the handshake completes.
3538 *
3539 * \param ssl The SSL context to query.
3540 * \param dtls_srtp_info The negotiated DTLS-SRTP informations:
3541 * - Protection profile in use.
3542 * A direct mapping of the iana defined value for protection
3543 * profile on an uint16_t.
3544 http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
3545 * #MBEDTLS_TLS_SRTP_UNSET if the use of SRTP was not negotiated
3546 * or peer's Hello packet was not parsed yet.
3547 * - mki size and value( if size is > 0 ).
3548 */
3549 void mbedtls_ssl_get_dtls_srtp_negotiation_result( const mbedtls_ssl_context *ssl,
3550 mbedtls_dtls_srtp_info *dtls_srtp_info );
3551 #endif /* MBEDTLS_SSL_DTLS_SRTP */
3552
3553 /**
3554 * \brief Set the maximum supported version sent from the client side
3555 * and/or accepted at the server side
3556 * (Default: MBEDTLS_SSL_MAX_MAJOR_VERSION, MBEDTLS_SSL_MAX_MINOR_VERSION)
3557 *
3558 * \note This ignores ciphersuites from higher versions.
3559 *
3560 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
3561 *
3562 * \param conf SSL configuration
3563 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
3564 * \param minor Minor version number (only MBEDTLS_SSL_MINOR_VERSION_3 supported)
3565 */
3566 void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor );
3567
3568 /**
3569 * \brief Set the minimum accepted SSL/TLS protocol version
3570 * (Default: TLS 1.2)
3571 *
3572 * \note Input outside of the SSL_MAX_XXXXX_VERSION and
3573 * SSL_MIN_XXXXX_VERSION range is ignored.
3574 *
3575 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
3576 *
3577 * \param conf SSL configuration
3578 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
3579 * \param minor Minor version number (only MBEDTLS_SSL_MINOR_VERSION_3 supported)
3580 */
3581 void mbedtls_ssl_conf_min_version( mbedtls_ssl_config *conf, int major, int minor );
3582
3583 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
3584 /**
3585 * \brief Enable or disable Encrypt-then-MAC
3586 * (Default: MBEDTLS_SSL_ETM_ENABLED)
3587 *
3588 * \note This should always be enabled, it is a security
3589 * improvement, and should not cause any interoperability
3590 * issue (used only if the peer supports it too).
3591 *
3592 * \param conf SSL configuration
3593 * \param etm MBEDTLS_SSL_ETM_ENABLED or MBEDTLS_SSL_ETM_DISABLED
3594 */
3595 void mbedtls_ssl_conf_encrypt_then_mac( mbedtls_ssl_config *conf, char etm );
3596 #endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
3597
3598 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
3599 /**
3600 * \brief Enable or disable Extended Master Secret negotiation.
3601 * (Default: MBEDTLS_SSL_EXTENDED_MS_ENABLED)
3602 *
3603 * \note This should always be enabled, it is a security fix to the
3604 * protocol, and should not cause any interoperability issue
3605 * (used only if the peer supports it too).
3606 *
3607 * \param conf SSL configuration
3608 * \param ems MBEDTLS_SSL_EXTENDED_MS_ENABLED or MBEDTLS_SSL_EXTENDED_MS_DISABLED
3609 */
3610 void mbedtls_ssl_conf_extended_master_secret( mbedtls_ssl_config *conf, char ems );
3611 #endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
3612
3613 #if defined(MBEDTLS_SSL_SRV_C)
3614 /**
3615 * \brief Whether to send a list of acceptable CAs in
3616 * CertificateRequest messages.
3617 * (Default: do send)
3618 *
3619 * \param conf SSL configuration
3620 * \param cert_req_ca_list MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or
3621 * MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED
3622 */
3623 void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf,
3624 char cert_req_ca_list );
3625 #endif /* MBEDTLS_SSL_SRV_C */
3626
3627 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
3628 /**
3629 * \brief Set the maximum fragment length to emit and/or negotiate.
3630 * (Typical: the smaller of #MBEDTLS_SSL_IN_CONTENT_LEN and
3631 * #MBEDTLS_SSL_OUT_CONTENT_LEN, usually `2^14` bytes)
3632 * (Server: set maximum fragment length to emit,
3633 * usually negotiated by the client during handshake)
3634 * (Client: set maximum fragment length to emit *and*
3635 * negotiate with the server during handshake)
3636 * (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE)
3637 *
3638 * \note On the client side, the maximum fragment length extension
3639 * *will not* be used, unless the maximum fragment length has
3640 * been set via this function to a value different than
3641 * #MBEDTLS_SSL_MAX_FRAG_LEN_NONE.
3642 *
3643 * \note With TLS, this currently only affects ApplicationData (sent
3644 * with \c mbedtls_ssl_read()), not handshake messages.
3645 * With DTLS, this affects both ApplicationData and handshake.
3646 *
3647 * \note This sets the maximum length for a record's payload,
3648 * excluding record overhead that will be added to it, see
3649 * \c mbedtls_ssl_get_record_expansion().
3650 *
3651 * \note For DTLS, it is also possible to set a limit for the total
3652 * size of daragrams passed to the transport layer, including
3653 * record overhead, see \c mbedtls_ssl_set_mtu().
3654 *
3655 * \param conf SSL configuration
3656 * \param mfl_code Code for maximum fragment length (allowed values:
3657 * MBEDTLS_SSL_MAX_FRAG_LEN_512, MBEDTLS_SSL_MAX_FRAG_LEN_1024,
3658 * MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096)
3659 *
3660 * \return 0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA
3661 */
3662 int mbedtls_ssl_conf_max_frag_len( mbedtls_ssl_config *conf, unsigned char mfl_code );
3663 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
3664
3665 #if defined(MBEDTLS_SSL_SRV_C)
3666 /**
3667 * \brief Pick the ciphersuites order according to the second parameter
3668 * in the SSL Server module (MBEDTLS_SSL_SRV_C).
3669 * (Default, if never called: MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER)
3670 *
3671 * \param conf SSL configuration
3672 * \param order Server or client (MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER
3673 * or MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_CLIENT)
3674 */
3675 void mbedtls_ssl_conf_preference_order( mbedtls_ssl_config *conf, int order );
3676 #endif /* MBEDTLS_SSL_SRV_C */
3677
3678 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
3679 /**
3680 * \brief Enable / Disable session tickets (client only).
3681 * (Default: MBEDTLS_SSL_SESSION_TICKETS_ENABLED.)
3682 *
3683 * \note On server, use \c mbedtls_ssl_conf_session_tickets_cb().
3684 *
3685 * \param conf SSL configuration
3686 * \param use_tickets Enable or disable (MBEDTLS_SSL_SESSION_TICKETS_ENABLED or
3687 * MBEDTLS_SSL_SESSION_TICKETS_DISABLED)
3688 */
3689 void mbedtls_ssl_conf_session_tickets( mbedtls_ssl_config *conf, int use_tickets );
3690 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
3691
3692 #if defined(MBEDTLS_SSL_RENEGOTIATION)
3693 /**
3694 * \brief Enable / Disable renegotiation support for connection when
3695 * initiated by peer
3696 * (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED)
3697 *
3698 * \warning It is recommended to always disable renegotation unless you
3699 * know you need it and you know what you're doing. In the
3700 * past, there have been several issues associated with
3701 * renegotiation or a poor understanding of its properties.
3702 *
3703 * \note Server-side, enabling renegotiation also makes the server
3704 * susceptible to a resource DoS by a malicious client.
3705 *
3706 * \param conf SSL configuration
3707 * \param renegotiation Enable or disable (MBEDTLS_SSL_RENEGOTIATION_ENABLED or
3708 * MBEDTLS_SSL_RENEGOTIATION_DISABLED)
3709 */
3710 void mbedtls_ssl_conf_renegotiation( mbedtls_ssl_config *conf, int renegotiation );
3711 #endif /* MBEDTLS_SSL_RENEGOTIATION */
3712
3713 /**
3714 * \brief Prevent or allow legacy renegotiation.
3715 * (Default: MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION)
3716 *
3717 * MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION allows connections to
3718 * be established even if the peer does not support
3719 * secure renegotiation, but does not allow renegotiation
3720 * to take place if not secure.
3721 * (Interoperable and secure option)
3722 *
3723 * MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION allows renegotiations
3724 * with non-upgraded peers. Allowing legacy renegotiation
3725 * makes the connection vulnerable to specific man in the
3726 * middle attacks. (See RFC 5746)
3727 * (Most interoperable and least secure option)
3728 *
3729 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE breaks off connections
3730 * if peer does not support secure renegotiation. Results
3731 * in interoperability issues with non-upgraded peers
3732 * that do not support renegotiation altogether.
3733 * (Most secure option, interoperability issues)
3734 *
3735 * \param conf SSL configuration
3736 * \param allow_legacy Prevent or allow (SSL_NO_LEGACY_RENEGOTIATION,
3737 * SSL_ALLOW_LEGACY_RENEGOTIATION or
3738 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE)
3739 */
3740 void mbedtls_ssl_conf_legacy_renegotiation( mbedtls_ssl_config *conf, int allow_legacy );
3741
3742 #if defined(MBEDTLS_SSL_RENEGOTIATION)
3743 /**
3744 * \brief Enforce renegotiation requests.
3745 * (Default: enforced, max_records = 16)
3746 *
3747 * When we request a renegotiation, the peer can comply or
3748 * ignore the request. This function allows us to decide
3749 * whether to enforce our renegotiation requests by closing
3750 * the connection if the peer doesn't comply.
3751 *
3752 * However, records could already be in transit from the peer
3753 * when the request is emitted. In order to increase
3754 * reliability, we can accept a number of records before the
3755 * expected handshake records.
3756 *
3757 * The optimal value is highly dependent on the specific usage
3758 * scenario.
3759 *
3760 * \note With DTLS and server-initiated renegotiation, the
3761 * HelloRequest is retransmited every time mbedtls_ssl_read() times
3762 * out or receives Application Data, until:
3763 * - max_records records have beens seen, if it is >= 0, or
3764 * - the number of retransmits that would happen during an
3765 * actual handshake has been reached.
3766 * Please remember the request might be lost a few times
3767 * if you consider setting max_records to a really low value.
3768 *
3769 * \warning On client, the grace period can only happen during
3770 * mbedtls_ssl_read(), as opposed to mbedtls_ssl_write() and mbedtls_ssl_renegotiate()
3771 * which always behave as if max_record was 0. The reason is,
3772 * if we receive application data from the server, we need a
3773 * place to write it, which only happens during mbedtls_ssl_read().
3774 *
3775 * \param conf SSL configuration
3776 * \param max_records Use MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to
3777 * enforce renegotiation, or a non-negative value to enforce
3778 * it but allow for a grace period of max_records records.
3779 */
3780 void mbedtls_ssl_conf_renegotiation_enforced( mbedtls_ssl_config *conf, int max_records );
3781
3782 /**
3783 * \brief Set record counter threshold for periodic renegotiation.
3784 * (Default: 2^48 - 1)
3785 *
3786 * Renegotiation is automatically triggered when a record
3787 * counter (outgoing or incoming) crosses the defined
3788 * threshold. The default value is meant to prevent the
3789 * connection from being closed when the counter is about to
3790 * reached its maximal value (it is not allowed to wrap).
3791 *
3792 * Lower values can be used to enforce policies such as "keys
3793 * must be refreshed every N packets with cipher X".
3794 *
3795 * The renegotiation period can be disabled by setting
3796 * conf->disable_renegotiation to
3797 * MBEDTLS_SSL_RENEGOTIATION_DISABLED.
3798 *
3799 * \note When the configured transport is
3800 * MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation
3801 * period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM,
3802 * the maximum renegotiation period is 2^64 - 1.
3803 *
3804 * \param conf SSL configuration
3805 * \param period The threshold value: a big-endian 64-bit number.
3806 */
3807 void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf,
3808 const unsigned char period[8] );
3809 #endif /* MBEDTLS_SSL_RENEGOTIATION */
3810
3811 /**
3812 * \brief Check if there is data already read from the
3813 * underlying transport but not yet processed.
3814 *
3815 * \param ssl SSL context
3816 *
3817 * \return 0 if nothing's pending, 1 otherwise.
3818 *
3819 * \note This is different in purpose and behaviour from
3820 * \c mbedtls_ssl_get_bytes_avail in that it considers
3821 * any kind of unprocessed data, not only unread
3822 * application data. If \c mbedtls_ssl_get_bytes
3823 * returns a non-zero value, this function will
3824 * also signal pending data, but the converse does
3825 * not hold. For example, in DTLS there might be
3826 * further records waiting to be processed from
3827 * the current underlying transport's datagram.
3828 *
3829 * \note If this function returns 1 (data pending), this
3830 * does not imply that a subsequent call to
3831 * \c mbedtls_ssl_read will provide any data;
3832 * e.g., the unprocessed data might turn out
3833 * to be an alert or a handshake message.
3834 *
3835 * \note This function is useful in the following situation:
3836 * If the SSL/TLS module successfully returns from an
3837 * operation - e.g. a handshake or an application record
3838 * read - and you're awaiting incoming data next, you
3839 * must not immediately idle on the underlying transport
3840 * to have data ready, but you need to check the value
3841 * of this function first. The reason is that the desired
3842 * data might already be read but not yet processed.
3843 * If, in contrast, a previous call to the SSL/TLS module
3844 * returned MBEDTLS_ERR_SSL_WANT_READ, it is not necessary
3845 * to call this function, as the latter error code entails
3846 * that all internal data has been processed.
3847 *
3848 */
3849 int mbedtls_ssl_check_pending( const mbedtls_ssl_context *ssl );
3850
3851 /**
3852 * \brief Return the number of application data bytes
3853 * remaining to be read from the current record.
3854 *
3855 * \param ssl SSL context
3856 *
3857 * \return How many bytes are available in the application
3858 * data record read buffer.
3859 *
3860 * \note When working over a datagram transport, this is
3861 * useful to detect the current datagram's boundary
3862 * in case \c mbedtls_ssl_read has written the maximal
3863 * amount of data fitting into the input buffer.
3864 *
3865 */
3866 size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl );
3867
3868 /**
3869 * \brief Return the result of the certificate verification
3870 *
3871 * \param ssl The SSL context to use.
3872 *
3873 * \return \c 0 if the certificate verification was successful.
3874 * \return \c -1u if the result is not available. This may happen
3875 * e.g. if the handshake aborts early, or a verification
3876 * callback returned a fatal error.
3877 * \return A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX
3878 * and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h.
3879 */
3880 uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl );
3881
3882 /**
3883 * \brief Return the name of the current ciphersuite
3884 *
3885 * \param ssl SSL context
3886 *
3887 * \return a string containing the ciphersuite name
3888 */
3889 const char *mbedtls_ssl_get_ciphersuite( const mbedtls_ssl_context *ssl );
3890
3891 /**
3892 * \brief Return the current TLS version
3893 *
3894 * \param ssl SSL context
3895 *
3896 * \return a string containing the TLS version
3897 */
3898 const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl );
3899
3900 /**
3901 * \brief Return the (maximum) number of bytes added by the record
3902 * layer: header + encryption/MAC overhead (inc. padding)
3903 *
3904 * \param ssl SSL context
3905 *
3906 * \return Current maximum record expansion in bytes
3907 */
3908 int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl );
3909
3910 /**
3911 * \brief Return the current maximum outgoing record payload in bytes.
3912 *
3913 * \note The logic to determine the maximum outgoing record payload is
3914 * version-specific. It takes into account various factors, such as
3915 * the mbedtls_config.h setting \c MBEDTLS_SSL_OUT_CONTENT_LEN, extensions
3916 * such as the max fragment length or record size limit extension if
3917 * used, and for DTLS the path MTU as configured and current
3918 * record expansion.
3919 *
3920 * \note With DTLS, \c mbedtls_ssl_write() will return an error if
3921 * called with a larger length value.
3922 * With TLS, \c mbedtls_ssl_write() will fragment the input if
3923 * necessary and return the number of bytes written; it is up
3924 * to the caller to call \c mbedtls_ssl_write() again in
3925 * order to send the remaining bytes if any.
3926 *
3927 * \sa mbedtls_ssl_get_max_out_record_payload()
3928 * \sa mbedtls_ssl_get_record_expansion()
3929 *
3930 * \param ssl SSL context
3931 *
3932 * \return Current maximum payload for an outgoing record,
3933 * or a negative error code.
3934 */
3935 int mbedtls_ssl_get_max_out_record_payload( const mbedtls_ssl_context *ssl );
3936
3937 /**
3938 * \brief Return the current maximum incoming record payload in bytes.
3939 *
3940 * \note The logic to determine the maximum outgoing record payload is
3941 * version-specific. It takes into account various factors, such as
3942 * the mbedtls_config.h setting \c MBEDTLS_SSL_IN_CONTENT_LEN, extensions
3943 * such as the max fragment length extension or record size limit
3944 * extension if used, and the current record expansion.
3945 *
3946 * \sa mbedtls_ssl_set_mtu()
3947 * \sa mbedtls_ssl_get_max_in_record_payload()
3948 * \sa mbedtls_ssl_get_record_expansion()
3949 *
3950 * \param ssl SSL context
3951 *
3952 * \return Current maximum payload for an outgoing record,
3953 * or a negative error code.
3954 */
3955 int mbedtls_ssl_get_max_in_record_payload( const mbedtls_ssl_context *ssl );
3956
3957 #if defined(MBEDTLS_X509_CRT_PARSE_C)
3958 /**
3959 * \brief Return the peer certificate from the current connection.
3960 *
3961 * \param ssl The SSL context to use. This must be initialized and setup.
3962 *
3963 * \return The current peer certificate, if available.
3964 * The returned certificate is owned by the SSL context and
3965 * is valid only until the next call to the SSL API.
3966 * \return \c NULL if no peer certificate is available. This might
3967 * be because the chosen ciphersuite doesn't use CRTs
3968 * (PSK-based ciphersuites, for example), or because
3969 * #MBEDTLS_SSL_KEEP_PEER_CERTIFICATE has been disabled,
3970 * allowing the stack to free the peer's CRT to save memory.
3971 *
3972 * \note For one-time inspection of the peer's certificate during
3973 * the handshake, consider registering an X.509 CRT verification
3974 * callback through mbedtls_ssl_conf_verify() instead of calling
3975 * this function. Using mbedtls_ssl_conf_verify() also comes at
3976 * the benefit of allowing you to influence the verification
3977 * process, for example by masking expected and tolerated
3978 * verification failures.
3979 *
3980 * \warning You must not use the pointer returned by this function
3981 * after any further call to the SSL API, including
3982 * mbedtls_ssl_read() and mbedtls_ssl_write(); this is
3983 * because the pointer might change during renegotiation,
3984 * which happens transparently to the user.
3985 * If you want to use the certificate across API calls,
3986 * you must make a copy.
3987 */
3988 const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert( const mbedtls_ssl_context *ssl );
3989 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3990
3991 #if defined(MBEDTLS_SSL_CLI_C)
3992 /**
3993 * \brief Export a session in order to resume it later.
3994 *
3995 * \param ssl The SSL context representing the connection for which to
3996 * to export a session structure for later resumption.
3997 * \param session The target structure in which to store the exported session.
3998 * This must have been initialized with mbedtls_ssl_init_session()
3999 * but otherwise be unused.
4000 *
4001 * \note This function can handle a variety of mechanisms for session
4002 * resumption: For TLS 1.2, both session ID-based resumption and
4003 * ticket-based resumption will be considered. For TLS 1.3,
4004 * once implemented, sessions equate to tickets, and calling
4005 * this function multiple times will export the available
4006 * tickets one a time until no further tickets are available,
4007 * in which case MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE will
4008 * be returned.
4009 *
4010 * \note Calling this function multiple times will only be useful
4011 * once TLS 1.3 is supported. For TLS 1.2 connections, this
4012 * function should be called at most once.
4013 *
4014 * \return \c 0 if successful. In this case, \p session can be used for
4015 * session resumption by passing it to mbedtls_ssl_set_session(),
4016 * and serialized for storage via mbedtls_ssl_session_save().
4017 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no further session
4018 * is available for export.
4019 * This error is a non-fatal, and has no observable effect on
4020 * the SSL context or the destination session.
4021 * \return Another negative error code on other kinds of failure.
4022 *
4023 * \sa mbedtls_ssl_set_session()
4024 * \sa mbedtls_ssl_session_save()
4025 */
4026 int mbedtls_ssl_get_session( const mbedtls_ssl_context *ssl,
4027 mbedtls_ssl_session *session );
4028 #endif /* MBEDTLS_SSL_CLI_C */
4029
4030 /**
4031 * \brief Perform the SSL handshake
4032 *
4033 * \param ssl SSL context
4034 *
4035 * \return \c 0 if successful.
4036 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4037 * if the handshake is incomplete and waiting for data to
4038 * be available for reading from or writing to the underlying
4039 * transport - in this case you must call this function again
4040 * when the underlying transport is ready for the operation.
4041 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4042 * operation is in progress (see
4043 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4044 * must call this function again when the operation is ready.
4045 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4046 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4047 * in this case you must call this function again to complete
4048 * the handshake when you're done attending other tasks.
4049 * \return #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED if DTLS is in use
4050 * and the client did not demonstrate reachability yet - in
4051 * this case you must stop using the context (see below).
4052 * \return Another SSL error code - in this case you must stop using
4053 * the context (see below).
4054 *
4055 * \warning If this function returns something other than
4056 * \c 0,
4057 * #MBEDTLS_ERR_SSL_WANT_READ,
4058 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4059 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4060 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
4061 * you must stop using the SSL context for reading or writing,
4062 * and either free it or call \c mbedtls_ssl_session_reset()
4063 * on it before re-using it for a new connection; the current
4064 * connection must be closed.
4065 *
4066 * \note If DTLS is in use, then you may choose to handle
4067 * #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging
4068 * purposes, as it is an expected return value rather than an
4069 * actual error, but you still need to reset/free the context.
4070 *
4071 * \note Remarks regarding event-driven DTLS:
4072 * If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
4073 * from the underlying transport layer is currently being processed,
4074 * and it is safe to idle until the timer or the underlying transport
4075 * signal a new event. This is not true for a successful handshake,
4076 * in which case the datagram of the underlying transport that is
4077 * currently being processed might or might not contain further
4078 * DTLS records.
4079 */
4080 int mbedtls_ssl_handshake( mbedtls_ssl_context *ssl );
4081
4082 /**
4083 * \brief Perform a single step of the SSL handshake
4084 *
4085 * \note The state of the context (ssl->state) will be at
4086 * the next state after this function returns \c 0. Do not
4087 * call this function if state is MBEDTLS_SSL_HANDSHAKE_OVER.
4088 *
4089 * \param ssl SSL context
4090 *
4091 * \return See mbedtls_ssl_handshake().
4092 *
4093 * \warning If this function returns something other than \c 0,
4094 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
4095 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4096 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
4097 * the SSL context for reading or writing, and either free it
4098 * or call \c mbedtls_ssl_session_reset() on it before
4099 * re-using it for a new connection; the current connection
4100 * must be closed.
4101 */
4102 int mbedtls_ssl_handshake_step( mbedtls_ssl_context *ssl );
4103
4104 #if defined(MBEDTLS_SSL_RENEGOTIATION)
4105 /**
4106 * \brief Initiate an SSL renegotiation on the running connection.
4107 * Client: perform the renegotiation right now.
4108 * Server: request renegotiation, which will be performed
4109 * during the next call to mbedtls_ssl_read() if honored by
4110 * client.
4111 *
4112 * \param ssl SSL context
4113 *
4114 * \return 0 if successful, or any mbedtls_ssl_handshake() return
4115 * value except #MBEDTLS_ERR_SSL_CLIENT_RECONNECT that can't
4116 * happen during a renegotiation.
4117 *
4118 * \warning If this function returns something other than \c 0,
4119 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
4120 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4121 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
4122 * the SSL context for reading or writing, and either free it
4123 * or call \c mbedtls_ssl_session_reset() on it before
4124 * re-using it for a new connection; the current connection
4125 * must be closed.
4126 *
4127 */
4128 int mbedtls_ssl_renegotiate( mbedtls_ssl_context *ssl );
4129 #endif /* MBEDTLS_SSL_RENEGOTIATION */
4130
4131 /**
4132 * \brief Read at most 'len' application data bytes
4133 *
4134 * \param ssl SSL context
4135 * \param buf buffer that will hold the data
4136 * \param len maximum number of bytes to read
4137 *
4138 * \return The (positive) number of bytes read if successful.
4139 * \return \c 0 if the read end of the underlying transport was closed
4140 * without sending a CloseNotify beforehand, which might happen
4141 * because of various reasons (internal error of an underlying
4142 * stack, non-conformant peer not sending a CloseNotify and
4143 * such) - in this case you must stop using the context
4144 * (see below).
4145 * \return #MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY if the underlying
4146 * transport is still functional, but the peer has
4147 * acknowledged to not send anything anymore.
4148 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4149 * if the handshake is incomplete and waiting for data to
4150 * be available for reading from or writing to the underlying
4151 * transport - in this case you must call this function again
4152 * when the underlying transport is ready for the operation.
4153 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4154 * operation is in progress (see
4155 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4156 * must call this function again when the operation is ready.
4157 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4158 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4159 * in this case you must call this function again to complete
4160 * the handshake when you're done attending other tasks.
4161 * \return #MBEDTLS_ERR_SSL_CLIENT_RECONNECT if we're at the server
4162 * side of a DTLS connection and the client is initiating a
4163 * new connection using the same source port. See below.
4164 * \return Another SSL error code - in this case you must stop using
4165 * the context (see below).
4166 *
4167 * \warning If this function returns something other than
4168 * a positive value,
4169 * #MBEDTLS_ERR_SSL_WANT_READ,
4170 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4171 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
4172 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
4173 * #MBEDTLS_ERR_SSL_CLIENT_RECONNECT,
4174 * you must stop using the SSL context for reading or writing,
4175 * and either free it or call \c mbedtls_ssl_session_reset()
4176 * on it before re-using it for a new connection; the current
4177 * connection must be closed.
4178 *
4179 * \note When this function returns #MBEDTLS_ERR_SSL_CLIENT_RECONNECT
4180 * (which can only happen server-side), it means that a client
4181 * is initiating a new connection using the same source port.
4182 * You can either treat that as a connection close and wait
4183 * for the client to resend a ClientHello, or directly
4184 * continue with \c mbedtls_ssl_handshake() with the same
4185 * context (as it has been reset internally). Either way, you
4186 * must make sure this is seen by the application as a new
4187 * connection: application state, if any, should be reset, and
4188 * most importantly the identity of the client must be checked
4189 * again. WARNING: not validating the identity of the client
4190 * again, or not transmitting the new identity to the
4191 * application layer, would allow authentication bypass!
4192 *
4193 * \note Remarks regarding event-driven DTLS:
4194 * - If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
4195 * from the underlying transport layer is currently being processed,
4196 * and it is safe to idle until the timer or the underlying transport
4197 * signal a new event.
4198 * - This function may return MBEDTLS_ERR_SSL_WANT_READ even if data was
4199 * initially available on the underlying transport, as this data may have
4200 * been only e.g. duplicated messages or a renegotiation request.
4201 * Therefore, you must be prepared to receive MBEDTLS_ERR_SSL_WANT_READ even
4202 * when reacting to an incoming-data event from the underlying transport.
4203 * - On success, the datagram of the underlying transport that is currently
4204 * being processed may contain further DTLS records. You should call
4205 * \c mbedtls_ssl_check_pending to check for remaining records.
4206 *
4207 */
4208 int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len );
4209
4210 /**
4211 * \brief Try to write exactly 'len' application data bytes
4212 *
4213 * \warning This function will do partial writes in some cases. If the
4214 * return value is non-negative but less than length, the
4215 * function must be called again with updated arguments:
4216 * buf + ret, len - ret (if ret is the return value) until
4217 * it returns a value equal to the last 'len' argument.
4218 *
4219 * \param ssl SSL context
4220 * \param buf buffer holding the data
4221 * \param len how many bytes must be written
4222 *
4223 * \return The (non-negative) number of bytes actually written if
4224 * successful (may be less than \p len).
4225 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4226 * if the handshake is incomplete and waiting for data to
4227 * be available for reading from or writing to the underlying
4228 * transport - in this case you must call this function again
4229 * when the underlying transport is ready for the operation.
4230 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4231 * operation is in progress (see
4232 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4233 * must call this function again when the operation is ready.
4234 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4235 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4236 * in this case you must call this function again to complete
4237 * the handshake when you're done attending other tasks.
4238 * \return Another SSL error code - in this case you must stop using
4239 * the context (see below).
4240 *
4241 * \warning If this function returns something other than
4242 * a non-negative value,
4243 * #MBEDTLS_ERR_SSL_WANT_READ,
4244 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4245 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4246 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
4247 * you must stop using the SSL context for reading or writing,
4248 * and either free it or call \c mbedtls_ssl_session_reset()
4249 * on it before re-using it for a new connection; the current
4250 * connection must be closed.
4251 *
4252 * \note When this function returns #MBEDTLS_ERR_SSL_WANT_WRITE/READ,
4253 * it must be called later with the *same* arguments,
4254 * until it returns a value greater that or equal to 0. When
4255 * the function returns #MBEDTLS_ERR_SSL_WANT_WRITE there may be
4256 * some partial data in the output buffer, however this is not
4257 * yet sent.
4258 *
4259 * \note If the requested length is greater than the maximum
4260 * fragment length (either the built-in limit or the one set
4261 * or negotiated with the peer), then:
4262 * - with TLS, less bytes than requested are written.
4263 * - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned.
4264 * \c mbedtls_ssl_get_max_out_record_payload() may be used to
4265 * query the active maximum fragment length.
4266 *
4267 * \note Attempting to write 0 bytes will result in an empty TLS
4268 * application record being sent.
4269 */
4270 int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len );
4271
4272 /**
4273 * \brief Send an alert message
4274 *
4275 * \param ssl SSL context
4276 * \param level The alert level of the message
4277 * (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL)
4278 * \param message The alert message (SSL_ALERT_MSG_*)
4279 *
4280 * \return 0 if successful, or a specific SSL error code.
4281 *
4282 * \note If this function returns something other than 0 or
4283 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
4284 * the SSL context for reading or writing, and either free it or
4285 * call \c mbedtls_ssl_session_reset() on it before re-using it
4286 * for a new connection; the current connection must be closed.
4287 */
4288 int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl,
4289 unsigned char level,
4290 unsigned char message );
4291 /**
4292 * \brief Notify the peer that the connection is being closed
4293 *
4294 * \param ssl SSL context
4295 *
4296 * \return 0 if successful, or a specific SSL error code.
4297 *
4298 * \note If this function returns something other than 0 or
4299 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
4300 * the SSL context for reading or writing, and either free it or
4301 * call \c mbedtls_ssl_session_reset() on it before re-using it
4302 * for a new connection; the current connection must be closed.
4303 */
4304 int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl );
4305
4306 /**
4307 * \brief Free referenced items in an SSL context and clear memory
4308 *
4309 * \param ssl SSL context
4310 */
4311 void mbedtls_ssl_free( mbedtls_ssl_context *ssl );
4312
4313 #if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION)
4314 /**
4315 * \brief Save an active connection as serialized data in a buffer.
4316 * This allows the freeing or re-using of the SSL context
4317 * while still picking up the connection later in a way that
4318 * it entirely transparent to the peer.
4319 *
4320 * \see mbedtls_ssl_context_load()
4321 *
4322 * \note This feature is currently only available under certain
4323 * conditions, see the documentation of the return value
4324 * #MBEDTLS_ERR_SSL_BAD_INPUT_DATA for details.
4325 *
4326 * \note When this function succeeds, it calls
4327 * mbedtls_ssl_session_reset() on \p ssl which as a result is
4328 * no longer associated with the connection that has been
4329 * serialized. This avoids creating copies of the connection
4330 * state. You're then free to either re-use the context
4331 * structure for a different connection, or call
4332 * mbedtls_ssl_free() on it. See the documentation of
4333 * mbedtls_ssl_session_reset() for more details.
4334 *
4335 * \param ssl The SSL context to save. On success, it is no longer
4336 * associated with the connection that has been serialized.
4337 * \param buf The buffer to write the serialized data to. It must be a
4338 * writeable buffer of at least \p buf_len bytes, or may be \c
4339 * NULL if \p buf_len is \c 0.
4340 * \param buf_len The number of bytes available for writing in \p buf.
4341 * \param olen The size in bytes of the data that has been or would have
4342 * been written. It must point to a valid \c size_t.
4343 *
4344 * \note \p olen is updated to the correct value regardless of
4345 * whether \p buf_len was large enough. This makes it possible
4346 * to determine the necessary size by calling this function
4347 * with \p buf set to \c NULL and \p buf_len to \c 0. However,
4348 * the value of \p olen is only guaranteed to be correct when
4349 * the function returns #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL or
4350 * \c 0. If the return value is different, then the value of
4351 * \p olen is undefined.
4352 *
4353 * \return \c 0 if successful.
4354 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
4355 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed
4356 * while reseting the context.
4357 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if a handshake is in
4358 * progress, or there is pending data for reading or sending,
4359 * or the connection does not use DTLS 1.2 with an AEAD
4360 * ciphersuite, or renegotiation is enabled.
4361 */
4362 int mbedtls_ssl_context_save( mbedtls_ssl_context *ssl,
4363 unsigned char *buf,
4364 size_t buf_len,
4365 size_t *olen );
4366
4367 /**
4368 * \brief Load serialized connection data to an SSL context.
4369 *
4370 * \see mbedtls_ssl_context_save()
4371 *
4372 * \warning The same serialized data must never be loaded into more
4373 * that one context. In order to ensure that, after
4374 * successfully loading serialized data to an SSL context, you
4375 * should immediately destroy or invalidate all copies of the
4376 * serialized data that was loaded. Loading the same data in
4377 * more than one context would cause severe security failures
4378 * including but not limited to loss of confidentiality.
4379 *
4380 * \note Before calling this function, the SSL context must be
4381 * prepared in one of the two following ways. The first way is
4382 * to take a context freshly initialised with
4383 * mbedtls_ssl_init() and call mbedtls_ssl_setup() on it with
4384 * the same ::mbedtls_ssl_config structure that was used in
4385 * the original connection. The second way is to
4386 * call mbedtls_ssl_session_reset() on a context that was
4387 * previously prepared as above but used in the meantime.
4388 * Either way, you must not use the context to perform a
4389 * handshake between calling mbedtls_ssl_setup() or
4390 * mbedtls_ssl_session_reset() and calling this function. You
4391 * may however call other setter functions in that time frame
4392 * as indicated in the note below.
4393 *
4394 * \note Before or after calling this function successfully, you
4395 * also need to configure some connection-specific callbacks
4396 * and settings before you can use the connection again
4397 * (unless they were already set before calling
4398 * mbedtls_ssl_session_reset() and the values are suitable for
4399 * the present connection). Specifically, you want to call
4400 * at least mbedtls_ssl_set_bio() and
4401 * mbedtls_ssl_set_timer_cb(). All other SSL setter functions
4402 * are not necessary to call, either because they're only used
4403 * in handshakes, or because the setting is already saved. You
4404 * might choose to call them anyway, for example in order to
4405 * share code between the cases of establishing a new
4406 * connection and the case of loading an already-established
4407 * connection.
4408 *
4409 * \note If you have new information about the path MTU, you want to
4410 * call mbedtls_ssl_set_mtu() after calling this function, as
4411 * otherwise this function would overwrite your
4412 * newly-configured value with the value that was active when
4413 * the context was saved.
4414 *
4415 * \note When this function returns an error code, it calls
4416 * mbedtls_ssl_free() on \p ssl. In this case, you need to
4417 * prepare the context with the usual sequence starting with a
4418 * call to mbedtls_ssl_init() if you want to use it again.
4419 *
4420 * \param ssl The SSL context structure to be populated. It must have
4421 * been prepared as described in the note above.
4422 * \param buf The buffer holding the serialized connection data. It must
4423 * be a readable buffer of at least \p len bytes.
4424 * \param len The size of the serialized data in bytes.
4425 *
4426 * \return \c 0 if successful.
4427 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
4428 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
4429 * comes from a different Mbed TLS version or build.
4430 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
4431 */
4432 int mbedtls_ssl_context_load( mbedtls_ssl_context *ssl,
4433 const unsigned char *buf,
4434 size_t len );
4435 #endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */
4436
4437 /**
4438 * \brief Initialize an SSL configuration context
4439 * Just makes the context ready for
4440 * mbedtls_ssl_config_defaults() or mbedtls_ssl_config_free().
4441 *
4442 * \note You need to call mbedtls_ssl_config_defaults() unless you
4443 * manually set all of the relevant fields yourself.
4444 *
4445 * \param conf SSL configuration context
4446 */
4447 void mbedtls_ssl_config_init( mbedtls_ssl_config *conf );
4448
4449 /**
4450 * \brief Load reasonnable default SSL configuration values.
4451 * (You need to call mbedtls_ssl_config_init() first.)
4452 *
4453 * \param conf SSL configuration context
4454 * \param endpoint MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
4455 * \param transport MBEDTLS_SSL_TRANSPORT_STREAM for TLS, or
4456 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS
4457 * \param preset a MBEDTLS_SSL_PRESET_XXX value
4458 *
4459 * \note See \c mbedtls_ssl_conf_transport() for notes on DTLS.
4460 *
4461 * \return 0 if successful, or
4462 * MBEDTLS_ERR_XXX_ALLOC_FAILED on memory allocation error.
4463 */
4464 int mbedtls_ssl_config_defaults( mbedtls_ssl_config *conf,
4465 int endpoint, int transport, int preset );
4466
4467 /**
4468 * \brief Free an SSL configuration context
4469 *
4470 * \param conf SSL configuration context
4471 */
4472 void mbedtls_ssl_config_free( mbedtls_ssl_config *conf );
4473
4474 /**
4475 * \brief Initialize SSL session structure
4476 *
4477 * \param session SSL session
4478 */
4479 void mbedtls_ssl_session_init( mbedtls_ssl_session *session );
4480
4481 /**
4482 * \brief Free referenced items in an SSL session including the
4483 * peer certificate and clear memory
4484 *
4485 * \note A session object can be freed even if the SSL context
4486 * that was used to retrieve the session is still in use.
4487 *
4488 * \param session SSL session
4489 */
4490 void mbedtls_ssl_session_free( mbedtls_ssl_session *session );
4491
4492 /**
4493 * \brief TLS-PRF function for key derivation.
4494 *
4495 * \param prf The tls_prf type function type to be used.
4496 * \param secret Secret for the key derivation function.
4497 * \param slen Length of the secret.
4498 * \param label String label for the key derivation function,
4499 * terminated with null character.
4500 * \param random Random bytes.
4501 * \param rlen Length of the random bytes buffer.
4502 * \param dstbuf The buffer holding the derived key.
4503 * \param dlen Length of the output buffer.
4504 *
4505 * \return 0 on success. An SSL specific error on failure.
4506 */
4507 int mbedtls_ssl_tls_prf( const mbedtls_tls_prf_types prf,
4508 const unsigned char *secret, size_t slen,
4509 const char *label,
4510 const unsigned char *random, size_t rlen,
4511 unsigned char *dstbuf, size_t dlen );
4512
4513 #ifdef __cplusplus
4514 }
4515 #endif
4516
4517 #endif /* ssl.h */
4518