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_TLS1_3_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_TLS1_3_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_TLS1_3_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_TLS1_3_KEY_EXCHANGE_MODE_ALL \
233 ( MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK | \
234 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL | \
235 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL ) /*!< All TLS 1.3 key exchanges */
236 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL \
237 ( MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK | \
238 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL ) /*!< All PSK-based TLS 1.3 key exchanges */
239 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL \
240 ( MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL | \
241 MBEDTLS_SSL_TLS1_3_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 */
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_TLS1_3_SIG_RSA_PKCS1_SHA256 0x0401
418 #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA384 0x0501
419 #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA512 0x0601
420
421 /* ECDSA algorithms */
422 #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP256R1_SHA256 0x0403
423 #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP384R1_SHA384 0x0503
424 #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP521R1_SHA512 0x0603
425
426 /* RSASSA-PSS algorithms with public key OID rsaEncryption */
427 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA256 0x0804
428 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA384 0x0805
429 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA512 0x0806
430
431 /* EdDSA algorithms */
432 #define MBEDTLS_TLS1_3_SIG_ED25519 0x0807
433 #define MBEDTLS_TLS1_3_SIG_ED448 0x0808
434
435 /* RSASSA-PSS algorithms with public key OID RSASSA-PSS */
436 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA256 0x0809
437 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA384 0x080A
438 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA512 0x080B
439
440 /* LEGACY ALGORITHMS */
441 #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA1 0x0201
442 #define MBEDTLS_TLS1_3_SIG_ECDSA_SHA1 0x0203
443
444 #define MBEDTLS_TLS1_3_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)
642 MBEDTLS_SSL_ENCRYPTED_EXTENSIONS,
643 MBEDTLS_SSL_CLIENT_CERTIFICATE_VERIFY,
644 #if defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE)
645 MBEDTLS_SSL_CLIENT_CCS_AFTER_SERVER_FINISHED,
646 #endif /* MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE */
647 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
648 }
649 mbedtls_ssl_states;
650
651 /**
652 * \brief Callback type: send data on the network.
653 *
654 * \note That callback may be either blocking or non-blocking.
655 *
656 * \param ctx Context for the send callback (typically a file descriptor)
657 * \param buf Buffer holding the data to send
658 * \param len Length of the data to send
659 *
660 * \return The callback must return the number of bytes sent if any,
661 * or a non-zero error code.
662 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_WRITE
663 * must be returned when the operation would block.
664 *
665 * \note The callback is allowed to send fewer bytes than requested.
666 * It must always return the number of bytes actually sent.
667 */
668 typedef int mbedtls_ssl_send_t( void *ctx,
669 const unsigned char *buf,
670 size_t len );
671
672 /**
673 * \brief Callback type: receive data from the network.
674 *
675 * \note That callback may be either blocking or non-blocking.
676 *
677 * \param ctx Context for the receive callback (typically a file
678 * descriptor)
679 * \param buf Buffer to write the received data to
680 * \param len Length of the receive buffer
681 *
682 * \returns If data has been received, the positive number of bytes received.
683 * \returns \c 0 if the connection has been closed.
684 * \returns If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ
685 * must be returned when the operation would block.
686 * \returns Another negative error code on other kinds of failures.
687 *
688 * \note The callback may receive fewer bytes than the length of the
689 * buffer. It must always return the number of bytes actually
690 * received and written to the buffer.
691 */
692 typedef int mbedtls_ssl_recv_t( void *ctx,
693 unsigned char *buf,
694 size_t len );
695
696 /**
697 * \brief Callback type: receive data from the network, with timeout
698 *
699 * \note That callback must block until data is received, or the
700 * timeout delay expires, or the operation is interrupted by a
701 * signal.
702 *
703 * \param ctx Context for the receive callback (typically a file descriptor)
704 * \param buf Buffer to write the received data to
705 * \param len Length of the receive buffer
706 * \param timeout Maximum number of milliseconds to wait for data
707 * 0 means no timeout (potentially waiting forever)
708 *
709 * \return The callback must return the number of bytes received,
710 * or a non-zero error code:
711 * \c MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out,
712 * \c MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal.
713 *
714 * \note The callback may receive fewer bytes than the length of the
715 * buffer. It must always return the number of bytes actually
716 * received and written to the buffer.
717 */
718 typedef int mbedtls_ssl_recv_timeout_t( void *ctx,
719 unsigned char *buf,
720 size_t len,
721 uint32_t timeout );
722 /**
723 * \brief Callback type: set a pair of timers/delays to watch
724 *
725 * \param ctx Context pointer
726 * \param int_ms Intermediate delay in milliseconds
727 * \param fin_ms Final delay in milliseconds
728 * 0 cancels the current timer.
729 *
730 * \note This callback must at least store the necessary information
731 * for the associated \c mbedtls_ssl_get_timer_t callback to
732 * return correct information.
733 *
734 * \note If using a event-driven style of programming, an event must
735 * be generated when the final delay is passed. The event must
736 * cause a call to \c mbedtls_ssl_handshake() with the proper
737 * SSL context to be scheduled. Care must be taken to ensure
738 * that at most one such call happens at a time.
739 *
740 * \note Only one timer at a time must be running. Calling this
741 * function while a timer is running must cancel it. Cancelled
742 * timers must not generate any event.
743 */
744 typedef void mbedtls_ssl_set_timer_t( void * ctx,
745 uint32_t int_ms,
746 uint32_t fin_ms );
747
748 /**
749 * \brief Callback type: get status of timers/delays
750 *
751 * \param ctx Context pointer
752 *
753 * \return This callback must return:
754 * -1 if cancelled (fin_ms == 0),
755 * 0 if none of the delays have passed,
756 * 1 if only the intermediate delay has passed,
757 * 2 if the final delay has passed.
758 */
759 typedef int mbedtls_ssl_get_timer_t( void * ctx );
760
761 /* Defined below */
762 typedef struct mbedtls_ssl_session mbedtls_ssl_session;
763 typedef struct mbedtls_ssl_context mbedtls_ssl_context;
764 typedef struct mbedtls_ssl_config mbedtls_ssl_config;
765
766 /* Defined in library/ssl_misc.h */
767 typedef struct mbedtls_ssl_transform mbedtls_ssl_transform;
768 typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params;
769 typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t;
770 #if defined(MBEDTLS_X509_CRT_PARSE_C)
771 typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert;
772 #endif
773 #if defined(MBEDTLS_SSL_PROTO_DTLS)
774 typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item;
775 #endif
776
777 /**
778 * \brief Callback type: server-side session cache getter
779 *
780 * The session cache is logically a key value store, with
781 * keys being session IDs and values being instances of
782 * mbedtls_ssl_session.
783 *
784 * This callback retrieves an entry in this key-value store.
785 *
786 * \param data The address of the session cache structure to query.
787 * \param session_id The buffer holding the session ID to query.
788 * \param session_id_len The length of \p session_id in Bytes.
789 * \param session The address of the session structure to populate.
790 * It is initialized with mbdtls_ssl_session_init(),
791 * and the callback must always leave it in a state
792 * where it can safely be freed via
793 * mbedtls_ssl_session_free() independent of the
794 * return code of this function.
795 *
796 * \return \c 0 on success
797 * \return A non-zero return value on failure.
798 *
799 */
800 typedef int mbedtls_ssl_cache_get_t( void *data,
801 unsigned char const *session_id,
802 size_t session_id_len,
803 mbedtls_ssl_session *session );
804 /**
805 * \brief Callback type: server-side session cache setter
806 *
807 * The session cache is logically a key value store, with
808 * keys being session IDs and values being instances of
809 * mbedtls_ssl_session.
810 *
811 * This callback sets an entry in this key-value store.
812 *
813 * \param data The address of the session cache structure to modify.
814 * \param session_id The buffer holding the session ID to query.
815 * \param session_id_len The length of \p session_id in Bytes.
816 * \param session The address of the session to be stored in the
817 * session cache.
818 *
819 * \return \c 0 on success
820 * \return A non-zero return value on failure.
821 */
822 typedef int mbedtls_ssl_cache_set_t( void *data,
823 unsigned char const *session_id,
824 size_t session_id_len,
825 const mbedtls_ssl_session *session );
826
827 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
828 #if defined(MBEDTLS_X509_CRT_PARSE_C)
829 /**
830 * \brief Callback type: start external signature operation.
831 *
832 * This callback is called during an SSL handshake to start
833 * a signature decryption operation using an
834 * external processor. The parameter \p cert contains
835 * the public key; it is up to the callback function to
836 * determine how to access the associated private key.
837 *
838 * This function typically sends or enqueues a request, and
839 * does not wait for the operation to complete. This allows
840 * the handshake step to be non-blocking.
841 *
842 * The parameters \p ssl and \p cert are guaranteed to remain
843 * valid throughout the handshake. On the other hand, this
844 * function must save the contents of \p hash if the value
845 * is needed for later processing, because the \p hash buffer
846 * is no longer valid after this function returns.
847 *
848 * This function may call mbedtls_ssl_set_async_operation_data()
849 * to store an operation context for later retrieval
850 * by the resume or cancel callback.
851 *
852 * \note For RSA signatures, this function must produce output
853 * that is consistent with PKCS#1 v1.5 in the same way as
854 * mbedtls_rsa_pkcs1_sign(). Before the private key operation,
855 * apply the padding steps described in RFC 8017, section 9.2
856 * "EMSA-PKCS1-v1_5" as follows.
857 * - If \p md_alg is #MBEDTLS_MD_NONE, apply the PKCS#1 v1.5
858 * encoding, treating \p hash as the DigestInfo to be
859 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
860 * from step 3, with `T = hash` and `tLen = hash_len`.
861 * - If `md_alg != MBEDTLS_MD_NONE`, apply the PKCS#1 v1.5
862 * encoding, treating \p hash as the hash to be encoded and
863 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
864 * from step 2, with `digestAlgorithm` obtained by calling
865 * mbedtls_oid_get_oid_by_md() on \p md_alg.
866 *
867 * \note For ECDSA signatures, the output format is the DER encoding
868 * `Ecdsa-Sig-Value` defined in
869 * [RFC 4492 section 5.4](https://tools.ietf.org/html/rfc4492#section-5.4).
870 *
871 * \param ssl The SSL connection instance. It should not be
872 * modified other than via
873 * mbedtls_ssl_set_async_operation_data().
874 * \param cert Certificate containing the public key.
875 * In simple cases, this is one of the pointers passed to
876 * mbedtls_ssl_conf_own_cert() when configuring the SSL
877 * connection. However, if other callbacks are used, this
878 * property may not hold. For example, if an SNI callback
879 * is registered with mbedtls_ssl_conf_sni(), then
880 * this callback determines what certificate is used.
881 * \param md_alg Hash algorithm.
882 * \param hash Buffer containing the hash. This buffer is
883 * no longer valid when the function returns.
884 * \param hash_len Size of the \c hash buffer in bytes.
885 *
886 * \return 0 if the operation was started successfully and the SSL
887 * stack should call the resume callback immediately.
888 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
889 * was started successfully and the SSL stack should return
890 * immediately without calling the resume callback yet.
891 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
892 * processor does not support this key. The SSL stack will
893 * use the private key object instead.
894 * \return Any other error indicates a fatal failure and is
895 * propagated up the call chain. The callback should
896 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
897 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
898 * directed in the documentation of this callback.
899 */
900 typedef int mbedtls_ssl_async_sign_t( mbedtls_ssl_context *ssl,
901 mbedtls_x509_crt *cert,
902 mbedtls_md_type_t md_alg,
903 const unsigned char *hash,
904 size_t hash_len );
905
906 /**
907 * \brief Callback type: start external decryption operation.
908 *
909 * This callback is called during an SSL handshake to start
910 * an RSA decryption operation using an
911 * external processor. The parameter \p cert contains
912 * the public key; it is up to the callback function to
913 * determine how to access the associated private key.
914 *
915 * This function typically sends or enqueues a request, and
916 * does not wait for the operation to complete. This allows
917 * the handshake step to be non-blocking.
918 *
919 * The parameters \p ssl and \p cert are guaranteed to remain
920 * valid throughout the handshake. On the other hand, this
921 * function must save the contents of \p input if the value
922 * is needed for later processing, because the \p input buffer
923 * is no longer valid after this function returns.
924 *
925 * This function may call mbedtls_ssl_set_async_operation_data()
926 * to store an operation context for later retrieval
927 * by the resume or cancel callback.
928 *
929 * \warning RSA decryption as used in TLS is subject to a potential
930 * timing side channel attack first discovered by Bleichenbacher
931 * in 1998. This attack can be remotely exploitable
932 * in practice. To avoid this attack, you must ensure that
933 * if the callback performs an RSA decryption, the time it
934 * takes to execute and return the result does not depend
935 * on whether the RSA decryption succeeded or reported
936 * invalid padding.
937 *
938 * \param ssl The SSL connection instance. It should not be
939 * modified other than via
940 * mbedtls_ssl_set_async_operation_data().
941 * \param cert Certificate containing the public key.
942 * In simple cases, this is one of the pointers passed to
943 * mbedtls_ssl_conf_own_cert() when configuring the SSL
944 * connection. However, if other callbacks are used, this
945 * property may not hold. For example, if an SNI callback
946 * is registered with mbedtls_ssl_conf_sni(), then
947 * this callback determines what certificate is used.
948 * \param input Buffer containing the input ciphertext. This buffer
949 * is no longer valid when the function returns.
950 * \param input_len Size of the \p input buffer in bytes.
951 *
952 * \return 0 if the operation was started successfully and the SSL
953 * stack should call the resume callback immediately.
954 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
955 * was started successfully and the SSL stack should return
956 * immediately without calling the resume callback yet.
957 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
958 * processor does not support this key. The SSL stack will
959 * use the private key object instead.
960 * \return Any other error indicates a fatal failure and is
961 * propagated up the call chain. The callback should
962 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
963 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
964 * directed in the documentation of this callback.
965 */
966 typedef int mbedtls_ssl_async_decrypt_t( mbedtls_ssl_context *ssl,
967 mbedtls_x509_crt *cert,
968 const unsigned char *input,
969 size_t input_len );
970 #endif /* MBEDTLS_X509_CRT_PARSE_C */
971
972 /**
973 * \brief Callback type: resume external operation.
974 *
975 * This callback is called during an SSL handshake to resume
976 * an external operation started by the
977 * ::mbedtls_ssl_async_sign_t or
978 * ::mbedtls_ssl_async_decrypt_t callback.
979 *
980 * This function typically checks the status of a pending
981 * request or causes the request queue to make progress, and
982 * does not wait for the operation to complete. This allows
983 * the handshake step to be non-blocking.
984 *
985 * This function may call mbedtls_ssl_get_async_operation_data()
986 * to retrieve an operation context set by the start callback.
987 * It may call mbedtls_ssl_set_async_operation_data() to modify
988 * this context.
989 *
990 * Note that when this function returns a status other than
991 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, it must free any
992 * resources associated with the operation.
993 *
994 * \param ssl The SSL connection instance. It should not be
995 * modified other than via
996 * mbedtls_ssl_set_async_operation_data().
997 * \param output Buffer containing the output (signature or decrypted
998 * data) on success.
999 * \param output_len On success, number of bytes written to \p output.
1000 * \param output_size Size of the \p output buffer in bytes.
1001 *
1002 * \return 0 if output of the operation is available in the
1003 * \p output buffer.
1004 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
1005 * is still in progress. Subsequent requests for progress
1006 * on the SSL connection will call the resume callback
1007 * again.
1008 * \return Any other error means that the operation is aborted.
1009 * The SSL handshake is aborted. The callback should
1010 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
1011 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
1012 * directed in the documentation of this callback.
1013 */
1014 typedef int mbedtls_ssl_async_resume_t( mbedtls_ssl_context *ssl,
1015 unsigned char *output,
1016 size_t *output_len,
1017 size_t output_size );
1018
1019 /**
1020 * \brief Callback type: cancel external operation.
1021 *
1022 * This callback is called if an SSL connection is closed
1023 * while an asynchronous operation is in progress. Note that
1024 * this callback is not called if the
1025 * ::mbedtls_ssl_async_resume_t callback has run and has
1026 * returned a value other than
1027 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, since in that case
1028 * the asynchronous operation has already completed.
1029 *
1030 * This function may call mbedtls_ssl_get_async_operation_data()
1031 * to retrieve an operation context set by the start callback.
1032 *
1033 * \param ssl The SSL connection instance. It should not be
1034 * modified.
1035 */
1036 typedef void mbedtls_ssl_async_cancel_t( mbedtls_ssl_context *ssl );
1037 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1038
1039 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) && \
1040 !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
1041 #define MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN 48
1042 #if defined(MBEDTLS_SHA256_C)
1043 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA256
1044 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 32
1045 #elif defined(MBEDTLS_SHA384_C)
1046 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA384
1047 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 48
1048 #elif defined(MBEDTLS_SHA1_C)
1049 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA1
1050 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 20
1051 #else
1052 /* This is already checked in check_config.h, but be sure. */
1053 #error "Bad configuration - need SHA-1, SHA-256 or SHA-512 enabled to compute digest of peer CRT."
1054 #endif
1055 #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED &&
1056 !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1057
1058 typedef struct
1059 {
1060 unsigned char client_application_traffic_secret_N[ MBEDTLS_TLS1_3_MD_MAX_SIZE ];
1061 unsigned char server_application_traffic_secret_N[ MBEDTLS_TLS1_3_MD_MAX_SIZE ];
1062 unsigned char exporter_master_secret [ MBEDTLS_TLS1_3_MD_MAX_SIZE ];
1063 unsigned char resumption_master_secret [ MBEDTLS_TLS1_3_MD_MAX_SIZE ];
1064 } mbedtls_ssl_tls13_application_secrets;
1065
1066 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1067
1068 #define MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH 255
1069 #define MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH 4
1070 /*
1071 * For code readability use a typedef for DTLS-SRTP profiles
1072 *
1073 * Use_srtp extension protection profiles values as defined in
1074 * http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
1075 *
1076 * Reminder: if this list is expanded mbedtls_ssl_check_srtp_profile_value
1077 * must be updated too.
1078 */
1079 #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80 ( (uint16_t) 0x0001)
1080 #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32 ( (uint16_t) 0x0002)
1081 #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80 ( (uint16_t) 0x0005)
1082 #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32 ( (uint16_t) 0x0006)
1083 /* This one is not iana defined, but for code readability. */
1084 #define MBEDTLS_TLS_SRTP_UNSET ( (uint16_t) 0x0000)
1085
1086 typedef uint16_t mbedtls_ssl_srtp_profile;
1087
1088 typedef struct mbedtls_dtls_srtp_info_t
1089 {
1090 /*! The SRTP profile that was negotiated. */
1091 mbedtls_ssl_srtp_profile MBEDTLS_PRIVATE(chosen_dtls_srtp_profile);
1092 /*! The length of mki_value. */
1093 uint16_t MBEDTLS_PRIVATE(mki_len);
1094 /*! The mki_value used, with max size of 256 bytes. */
1095 unsigned char MBEDTLS_PRIVATE(mki_value)[MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH];
1096 }
1097 mbedtls_dtls_srtp_info;
1098
1099 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1100
1101 /*
1102 * This structure is used for storing current session data.
1103 *
1104 * Note: when changing this definition, we need to check and update:
1105 * - in tests/suites/test_suite_ssl.function:
1106 * ssl_populate_session() and ssl_serialize_session_save_load()
1107 * - in library/ssl_tls.c:
1108 * mbedtls_ssl_session_init() and mbedtls_ssl_session_free()
1109 * mbedtls_ssl_session_save() and ssl_session_load()
1110 * ssl_session_copy()
1111 */
1112 struct mbedtls_ssl_session
1113 {
1114 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
1115 unsigned char MBEDTLS_PRIVATE(mfl_code); /*!< MaxFragmentLength negotiated by peer */
1116 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
1117
1118 unsigned char MBEDTLS_PRIVATE(exported);
1119
1120 /* This field is temporarily duplicated with mbedtls_ssl_context.minor_ver.
1121 * Once runtime negotiation of TLS 1.2 and TLS 1.3 is implemented, it needs
1122 * to be studied whether one of them can be removed. */
1123 unsigned char MBEDTLS_PRIVATE(minor_ver); /*!< The TLS version used in the session. */
1124
1125 #if defined(MBEDTLS_HAVE_TIME)
1126 mbedtls_time_t MBEDTLS_PRIVATE(start); /*!< starting time */
1127 #endif
1128 int MBEDTLS_PRIVATE(ciphersuite); /*!< chosen ciphersuite */
1129 int MBEDTLS_PRIVATE(compression); /*!< chosen compression */
1130 size_t MBEDTLS_PRIVATE(id_len); /*!< session id length */
1131 unsigned char MBEDTLS_PRIVATE(id)[32]; /*!< session identifier */
1132 unsigned char MBEDTLS_PRIVATE(master)[48]; /*!< the master secret */
1133
1134 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1135 #if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
1136 mbedtls_x509_crt *MBEDTLS_PRIVATE(peer_cert); /*!< peer X.509 cert chain */
1137 #else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1138 /*! The digest of the peer's end-CRT. This must be kept to detect CRT
1139 * changes during renegotiation, mitigating the triple handshake attack. */
1140 unsigned char *MBEDTLS_PRIVATE(peer_cert_digest);
1141 size_t MBEDTLS_PRIVATE(peer_cert_digest_len);
1142 mbedtls_md_type_t MBEDTLS_PRIVATE(peer_cert_digest_type);
1143 #endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1144 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1145 uint32_t MBEDTLS_PRIVATE(verify_result); /*!< verification result */
1146
1147 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
1148 unsigned char *MBEDTLS_PRIVATE(ticket); /*!< RFC 5077 session ticket */
1149 size_t MBEDTLS_PRIVATE(ticket_len); /*!< session ticket length */
1150 uint32_t MBEDTLS_PRIVATE(ticket_lifetime); /*!< ticket lifetime hint */
1151 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
1152
1153 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1154 int MBEDTLS_PRIVATE(encrypt_then_mac); /*!< flag for EtM activation */
1155 #endif
1156
1157 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1158 mbedtls_ssl_tls13_application_secrets MBEDTLS_PRIVATE(app_secrets);
1159 #endif
1160 };
1161
1162 /*
1163 * Identifiers for PRFs used in various versions of TLS.
1164 */
1165 typedef enum
1166 {
1167 MBEDTLS_SSL_TLS_PRF_NONE,
1168 MBEDTLS_SSL_TLS_PRF_SHA384,
1169 MBEDTLS_SSL_TLS_PRF_SHA256,
1170 MBEDTLS_SSL_HKDF_EXPAND_SHA384,
1171 MBEDTLS_SSL_HKDF_EXPAND_SHA256
1172 }
1173 mbedtls_tls_prf_types;
1174
1175 typedef enum
1176 {
1177 MBEDTLS_SSL_KEY_EXPORT_TLS12_MASTER_SECRET = 0,
1178 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1179 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_EARLY_SECRET,
1180 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_EARLY_EXPORTER_SECRET,
1181 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_HANDSHAKE_TRAFFIC_SECRET,
1182 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_SERVER_HANDSHAKE_TRAFFIC_SECRET,
1183 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_APPLICATION_TRAFFIC_SECRET,
1184 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_SERVER_APPLICATION_TRAFFIC_SECRET,
1185 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1186 } mbedtls_ssl_key_export_type;
1187
1188 /**
1189 * \brief Callback type: Export key alongside random values for
1190 * session identification, and PRF for
1191 * implementation of TLS key exporters.
1192 *
1193 * \param p_expkey Context for the callback.
1194 * \param type The type of the key that is being exported.
1195 * \param secret The address of the buffer holding the secret
1196 * that's being exporterd.
1197 * \param secret_len The length of \p secret in bytes.
1198 * \param client_random The client random bytes.
1199 * \param server_random The server random bytes.
1200 * \param tls_prf_type The identifier for the PRF used in the handshake
1201 * to which the key belongs.
1202 */
1203 typedef void mbedtls_ssl_export_keys_t( void *p_expkey,
1204 mbedtls_ssl_key_export_type type,
1205 const unsigned char *secret,
1206 size_t secret_len,
1207 const unsigned char client_random[32],
1208 const unsigned char server_random[32],
1209 mbedtls_tls_prf_types tls_prf_type );
1210
1211 /**
1212 * SSL/TLS configuration to be shared between mbedtls_ssl_context structures.
1213 */
1214 struct mbedtls_ssl_config
1215 {
1216 /* Group items mostly by size. This helps to reduce memory wasted to
1217 * padding. It also helps to keep smaller fields early in the structure,
1218 * so that elements tend to be in the 128-element direct access window
1219 * on Arm Thumb, which reduces the code size. */
1220
1221 unsigned char MBEDTLS_PRIVATE(max_major_ver); /*!< max. major version used */
1222 unsigned char MBEDTLS_PRIVATE(max_minor_ver); /*!< max. minor version used */
1223 unsigned char MBEDTLS_PRIVATE(min_major_ver); /*!< min. major version used */
1224 unsigned char MBEDTLS_PRIVATE(min_minor_ver); /*!< min. minor version used */
1225
1226 /*
1227 * Flags (could be bit-fields to save RAM, but separate bytes make
1228 * the code smaller on architectures with an instruction for direct
1229 * byte access).
1230 */
1231
1232 uint8_t MBEDTLS_PRIVATE(endpoint); /*!< 0: client, 1: server */
1233 uint8_t MBEDTLS_PRIVATE(transport); /*!< 0: stream (TLS), 1: datagram (DTLS) */
1234 uint8_t MBEDTLS_PRIVATE(authmode); /*!< MBEDTLS_SSL_VERIFY_XXX */
1235 /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE */
1236 uint8_t MBEDTLS_PRIVATE(allow_legacy_renegotiation); /*!< MBEDTLS_LEGACY_XXX */
1237 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
1238 uint8_t MBEDTLS_PRIVATE(mfl_code); /*!< desired fragment length indicator
1239 (MBEDTLS_SSL_MAX_FRAG_LEN_XXX) */
1240 #endif
1241 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1242 uint8_t MBEDTLS_PRIVATE(encrypt_then_mac); /*!< negotiate encrypt-then-mac? */
1243 #endif
1244 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
1245 uint8_t MBEDTLS_PRIVATE(extended_ms); /*!< negotiate extended master secret? */
1246 #endif
1247 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1248 uint8_t MBEDTLS_PRIVATE(anti_replay); /*!< detect and prevent replay? */
1249 #endif
1250 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1251 uint8_t MBEDTLS_PRIVATE(disable_renegotiation); /*!< disable renegotiation? */
1252 #endif
1253 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
1254 uint8_t MBEDTLS_PRIVATE(session_tickets); /*!< use session tickets? */
1255 #endif
1256 #if defined(MBEDTLS_SSL_SRV_C)
1257 uint8_t MBEDTLS_PRIVATE(cert_req_ca_list); /*!< enable sending CA list in
1258 Certificate Request messages? */
1259 uint8_t MBEDTLS_PRIVATE(respect_cli_pref); /*!< pick the ciphersuite according to
1260 the client's preferences rather
1261 than ours? */
1262 #endif
1263 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1264 uint8_t MBEDTLS_PRIVATE(ignore_unexpected_cid); /*!< Should DTLS record with
1265 * unexpected CID
1266 * lead to failure? */
1267 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1268 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1269 uint8_t MBEDTLS_PRIVATE(dtls_srtp_mki_support); /* support having mki_value
1270 in the use_srtp extension? */
1271 #endif
1272
1273 /*
1274 * Pointers
1275 */
1276
1277 /** Allowed ciphersuites for (D)TLS 1.2 (0-terminated) */
1278 const int *MBEDTLS_PRIVATE(ciphersuite_list);
1279
1280 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1281 /** Allowed TLS 1.3 key exchange modes. */
1282 int MBEDTLS_PRIVATE(tls13_kex_modes);
1283 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1284
1285 /** Callback for printing debug output */
1286 void (*MBEDTLS_PRIVATE(f_dbg))(void *, int, const char *, int, const char *);
1287 void *MBEDTLS_PRIVATE(p_dbg); /*!< context for the debug function */
1288
1289 /** Callback for getting (pseudo-)random numbers */
1290 int (*MBEDTLS_PRIVATE(f_rng))(void *, unsigned char *, size_t);
1291 void *MBEDTLS_PRIVATE(p_rng); /*!< context for the RNG function */
1292
1293 /** Callback to retrieve a session from the cache */
1294 mbedtls_ssl_cache_get_t *MBEDTLS_PRIVATE(f_get_cache);
1295 /** Callback to store a session into the cache */
1296 mbedtls_ssl_cache_set_t *MBEDTLS_PRIVATE(f_set_cache);
1297 void *MBEDTLS_PRIVATE(p_cache); /*!< context for cache callbacks */
1298
1299 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
1300 /** Callback for setting cert according to SNI extension */
1301 int (*MBEDTLS_PRIVATE(f_sni))(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
1302 void *MBEDTLS_PRIVATE(p_sni); /*!< context for SNI callback */
1303 #endif
1304
1305 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1306 /** Callback to customize X.509 certificate chain verification */
1307 int (*MBEDTLS_PRIVATE(f_vrfy))(void *, mbedtls_x509_crt *, int, uint32_t *);
1308 void *MBEDTLS_PRIVATE(p_vrfy); /*!< context for X.509 verify calllback */
1309 #endif
1310
1311 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
1312 /** Callback to retrieve PSK key from identity */
1313 int (*MBEDTLS_PRIVATE(f_psk))(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
1314 void *MBEDTLS_PRIVATE(p_psk); /*!< context for PSK callback */
1315 #endif
1316
1317 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1318 /** Callback to create & write a cookie for ClientHello veirifcation */
1319 int (*MBEDTLS_PRIVATE(f_cookie_write))( void *, unsigned char **, unsigned char *,
1320 const unsigned char *, size_t );
1321 /** Callback to verify validity of a ClientHello cookie */
1322 int (*MBEDTLS_PRIVATE(f_cookie_check))( void *, const unsigned char *, size_t,
1323 const unsigned char *, size_t );
1324 void *MBEDTLS_PRIVATE(p_cookie); /*!< context for the cookie callbacks */
1325 #endif
1326
1327 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
1328 /** Callback to create & write a session ticket */
1329 int (*MBEDTLS_PRIVATE(f_ticket_write))( void *, const mbedtls_ssl_session *,
1330 unsigned char *, const unsigned char *, size_t *, uint32_t * );
1331 /** Callback to parse a session ticket into a session structure */
1332 int (*MBEDTLS_PRIVATE(f_ticket_parse))( void *, mbedtls_ssl_session *, unsigned char *, size_t);
1333 void *MBEDTLS_PRIVATE(p_ticket); /*!< context for the ticket callbacks */
1334 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
1335
1336 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1337 size_t MBEDTLS_PRIVATE(cid_len); /*!< The length of CIDs for incoming DTLS records. */
1338 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1339
1340 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1341 const mbedtls_x509_crt_profile *MBEDTLS_PRIVATE(cert_profile); /*!< verification profile */
1342 mbedtls_ssl_key_cert *MBEDTLS_PRIVATE(key_cert); /*!< own certificate/key pair(s) */
1343 mbedtls_x509_crt *MBEDTLS_PRIVATE(ca_chain); /*!< trusted CAs */
1344 mbedtls_x509_crl *MBEDTLS_PRIVATE(ca_crl); /*!< trusted CAs CRLs */
1345 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
1346 mbedtls_x509_crt_ca_cb_t MBEDTLS_PRIVATE(f_ca_cb);
1347 void *MBEDTLS_PRIVATE(p_ca_cb);
1348 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
1349 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1350
1351 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
1352 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1353 mbedtls_ssl_async_sign_t *MBEDTLS_PRIVATE(f_async_sign_start); /*!< start asynchronous signature operation */
1354 mbedtls_ssl_async_decrypt_t *MBEDTLS_PRIVATE(f_async_decrypt_start); /*!< start asynchronous decryption operation */
1355 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1356 mbedtls_ssl_async_resume_t *MBEDTLS_PRIVATE(f_async_resume); /*!< resume asynchronous operation */
1357 mbedtls_ssl_async_cancel_t *MBEDTLS_PRIVATE(f_async_cancel); /*!< cancel asynchronous operation */
1358 void *MBEDTLS_PRIVATE(p_async_config_data); /*!< Configuration data set by mbedtls_ssl_conf_async_private_cb(). */
1359 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1360
1361 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
1362 const int *MBEDTLS_PRIVATE(sig_hashes); /*!< allowed signature hashes */
1363
1364 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1365 const uint16_t *MBEDTLS_PRIVATE(tls13_sig_algs); /*!< allowed signature algorithms for TLS 1.3 */
1366 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1367 #endif
1368
1369 #if defined(MBEDTLS_ECP_C) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1370 const mbedtls_ecp_group_id *MBEDTLS_PRIVATE(curve_list); /*!< allowed curves */
1371 #endif
1372
1373 const uint16_t *MBEDTLS_PRIVATE(group_list); /*!< allowed IANA NamedGroups */
1374
1375 #if defined(MBEDTLS_DHM_C)
1376 mbedtls_mpi MBEDTLS_PRIVATE(dhm_P); /*!< prime modulus for DHM */
1377 mbedtls_mpi MBEDTLS_PRIVATE(dhm_G); /*!< generator for DHM */
1378 #endif
1379
1380 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
1381
1382 #if defined(MBEDTLS_USE_PSA_CRYPTO)
1383 psa_key_id_t MBEDTLS_PRIVATE(psk_opaque); /*!< PSA key slot holding opaque PSK. This field
1384 * should only be set via
1385 * mbedtls_ssl_conf_psk_opaque().
1386 * If either no PSK or a raw PSK have been
1387 * configured, this has value \c 0.
1388 */
1389 #endif /* MBEDTLS_USE_PSA_CRYPTO */
1390
1391 unsigned char *MBEDTLS_PRIVATE(psk); /*!< The raw pre-shared key. This field should
1392 * only be set via mbedtls_ssl_conf_psk().
1393 * If either no PSK or an opaque PSK
1394 * have been configured, this has value NULL. */
1395 size_t MBEDTLS_PRIVATE(psk_len); /*!< The length of the raw pre-shared key.
1396 * This field should only be set via
1397 * mbedtls_ssl_conf_psk().
1398 * Its value is non-zero if and only if
1399 * \c psk is not \c NULL. */
1400
1401 unsigned char *MBEDTLS_PRIVATE(psk_identity); /*!< The PSK identity for PSK negotiation.
1402 * This field should only be set via
1403 * mbedtls_ssl_conf_psk().
1404 * This is set if and only if either
1405 * \c psk or \c psk_opaque are set. */
1406 size_t MBEDTLS_PRIVATE(psk_identity_len);/*!< The length of PSK identity.
1407 * This field should only be set via
1408 * mbedtls_ssl_conf_psk().
1409 * Its value is non-zero if and only if
1410 * \c psk is not \c NULL or \c psk_opaque
1411 * is not \c 0. */
1412 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
1413
1414 #if defined(MBEDTLS_SSL_ALPN)
1415 const char **MBEDTLS_PRIVATE(alpn_list); /*!< ordered list of protocols */
1416 #endif
1417
1418 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1419 /*! ordered list of supported srtp profile */
1420 const mbedtls_ssl_srtp_profile *MBEDTLS_PRIVATE(dtls_srtp_profile_list);
1421 /*! number of supported profiles */
1422 size_t MBEDTLS_PRIVATE(dtls_srtp_profile_list_len);
1423 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1424
1425 /*
1426 * Numerical settings (int)
1427 */
1428
1429 uint32_t MBEDTLS_PRIVATE(read_timeout); /*!< timeout for mbedtls_ssl_read (ms) */
1430
1431 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1432 uint32_t MBEDTLS_PRIVATE(hs_timeout_min); /*!< initial value of the handshake
1433 retransmission timeout (ms) */
1434 uint32_t MBEDTLS_PRIVATE(hs_timeout_max); /*!< maximum value of the handshake
1435 retransmission timeout (ms) */
1436 #endif
1437
1438 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1439 int MBEDTLS_PRIVATE(renego_max_records); /*!< grace period for renegotiation */
1440 unsigned char MBEDTLS_PRIVATE(renego_period)[8]; /*!< value of the record counters
1441 that triggers renegotiation */
1442 #endif
1443
1444 unsigned int MBEDTLS_PRIVATE(badmac_limit); /*!< limit of records with a bad MAC */
1445
1446 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
1447 unsigned int MBEDTLS_PRIVATE(dhm_min_bitlen); /*!< min. bit length of the DHM prime */
1448 #endif
1449 };
1450
1451 struct mbedtls_ssl_context
1452 {
1453 const mbedtls_ssl_config *MBEDTLS_PRIVATE(conf); /*!< configuration information */
1454
1455 /*
1456 * Miscellaneous
1457 */
1458 int MBEDTLS_PRIVATE(state); /*!< SSL handshake: current state */
1459 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1460 int MBEDTLS_PRIVATE(renego_status); /*!< Initial, in progress, pending? */
1461 int MBEDTLS_PRIVATE(renego_records_seen); /*!< Records since renego request, or with DTLS,
1462 number of retransmissions of request if
1463 renego_max_records is < 0 */
1464 #endif /* MBEDTLS_SSL_RENEGOTIATION */
1465
1466 int MBEDTLS_PRIVATE(major_ver); /*!< equal to MBEDTLS_SSL_MAJOR_VERSION_3 */
1467
1468 /* This field is temporarily duplicated with mbedtls_ssl_context.minor_ver.
1469 * Once runtime negotiation of TLS 1.2 and TLS 1.3 is implemented, it needs
1470 * to be studied whether one of them can be removed. */
1471 int MBEDTLS_PRIVATE(minor_ver); /*!< one of MBEDTLS_SSL_MINOR_VERSION_x macros */
1472 unsigned MBEDTLS_PRIVATE(badmac_seen); /*!< records with a bad MAC received */
1473
1474 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1475 /** Callback to customize X.509 certificate chain verification */
1476 int (*MBEDTLS_PRIVATE(f_vrfy))(void *, mbedtls_x509_crt *, int, uint32_t *);
1477 void *MBEDTLS_PRIVATE(p_vrfy); /*!< context for X.509 verify callback */
1478 #endif
1479
1480 mbedtls_ssl_send_t *MBEDTLS_PRIVATE(f_send); /*!< Callback for network send */
1481 mbedtls_ssl_recv_t *MBEDTLS_PRIVATE(f_recv); /*!< Callback for network receive */
1482 mbedtls_ssl_recv_timeout_t *MBEDTLS_PRIVATE(f_recv_timeout);
1483 /*!< Callback for network receive with timeout */
1484
1485 void *MBEDTLS_PRIVATE(p_bio); /*!< context for I/O operations */
1486
1487 /*
1488 * Session layer
1489 */
1490 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_in); /*!< current session data (in) */
1491 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_out); /*!< current session data (out) */
1492 mbedtls_ssl_session *MBEDTLS_PRIVATE(session); /*!< negotiated session data */
1493 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_negotiate); /*!< session data in negotiation */
1494
1495 mbedtls_ssl_handshake_params *MBEDTLS_PRIVATE(handshake); /*!< params required only during
1496 the handshake process */
1497
1498 /*
1499 * Record layer transformations
1500 */
1501 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_in); /*!< current transform params (in)
1502 * This is always a reference,
1503 * never an owning pointer. */
1504 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_out); /*!< current transform params (out)
1505 * This is always a reference,
1506 * never an owning pointer. */
1507 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform); /*!< negotiated transform params
1508 * This pointer owns the transform
1509 * it references. */
1510 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_negotiate); /*!< transform params in negotiation
1511 * This pointer owns the transform
1512 * it references. */
1513
1514 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1515 /*! The application data transform in TLS 1.3.
1516 * This pointer owns the transform it references. */
1517 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_application);
1518 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1519
1520 /*
1521 * Timers
1522 */
1523 void *MBEDTLS_PRIVATE(p_timer); /*!< context for the timer callbacks */
1524
1525 mbedtls_ssl_set_timer_t *MBEDTLS_PRIVATE(f_set_timer); /*!< set timer callback */
1526 mbedtls_ssl_get_timer_t *MBEDTLS_PRIVATE(f_get_timer); /*!< get timer callback */
1527
1528 /*
1529 * Record layer (incoming data)
1530 */
1531 unsigned char *MBEDTLS_PRIVATE(in_buf); /*!< input buffer */
1532 unsigned char *MBEDTLS_PRIVATE(in_ctr); /*!< 64-bit incoming message counter
1533 TLS: maintained by us
1534 DTLS: read from peer */
1535 unsigned char *MBEDTLS_PRIVATE(in_hdr); /*!< start of record header */
1536 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1537 unsigned char *MBEDTLS_PRIVATE(in_cid); /*!< The start of the CID;
1538 * (the end is marked by in_len). */
1539 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1540 unsigned char *MBEDTLS_PRIVATE(in_len); /*!< two-bytes message length field */
1541 unsigned char *MBEDTLS_PRIVATE(in_iv); /*!< ivlen-byte IV */
1542 unsigned char *MBEDTLS_PRIVATE(in_msg); /*!< message contents (in_iv+ivlen) */
1543 unsigned char *MBEDTLS_PRIVATE(in_offt); /*!< read offset in application data */
1544
1545 int MBEDTLS_PRIVATE(in_msgtype); /*!< record header: message type */
1546 size_t MBEDTLS_PRIVATE(in_msglen); /*!< record header: message length */
1547 size_t MBEDTLS_PRIVATE(in_left); /*!< amount of data read so far */
1548 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1549 size_t MBEDTLS_PRIVATE(in_buf_len); /*!< length of input buffer */
1550 #endif
1551 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1552 uint16_t MBEDTLS_PRIVATE(in_epoch); /*!< DTLS epoch for incoming records */
1553 size_t MBEDTLS_PRIVATE(next_record_offset); /*!< offset of the next record in datagram
1554 (equal to in_left if none) */
1555 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1556 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1557 uint64_t MBEDTLS_PRIVATE(in_window_top); /*!< last validated record seq_num */
1558 uint64_t MBEDTLS_PRIVATE(in_window); /*!< bitmask for replay detection */
1559 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
1560
1561 size_t MBEDTLS_PRIVATE(in_hslen); /*!< current handshake message length,
1562 including the handshake header */
1563 int MBEDTLS_PRIVATE(nb_zero); /*!< # of 0-length encrypted messages */
1564
1565 int MBEDTLS_PRIVATE(keep_current_message); /*!< drop or reuse current message
1566 on next call to record layer? */
1567
1568 /* The following three variables indicate if and, if yes,
1569 * what kind of alert is pending to be sent.
1570 */
1571 unsigned char MBEDTLS_PRIVATE(send_alert); /*!< Determines if a fatal alert
1572 should be sent. Values:
1573 - \c 0 , no alert is to be sent.
1574 - \c 1 , alert is to be sent. */
1575 unsigned char MBEDTLS_PRIVATE(alert_type); /*!< Type of alert if send_alert
1576 != 0 */
1577 int MBEDTLS_PRIVATE(alert_reason); /*!< The error code to be returned
1578 to the user once the fatal alert
1579 has been sent. */
1580
1581 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1582 uint8_t MBEDTLS_PRIVATE(disable_datagram_packing); /*!< Disable packing multiple records
1583 * within a single datagram. */
1584 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1585
1586 /*
1587 * Record layer (outgoing data)
1588 */
1589 unsigned char *MBEDTLS_PRIVATE(out_buf); /*!< output buffer */
1590 unsigned char *MBEDTLS_PRIVATE(out_ctr); /*!< 64-bit outgoing message counter */
1591 unsigned char *MBEDTLS_PRIVATE(out_hdr); /*!< start of record header */
1592 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1593 unsigned char *MBEDTLS_PRIVATE(out_cid); /*!< The start of the CID;
1594 * (the end is marked by in_len). */
1595 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1596 unsigned char *MBEDTLS_PRIVATE(out_len); /*!< two-bytes message length field */
1597 unsigned char *MBEDTLS_PRIVATE(out_iv); /*!< ivlen-byte IV */
1598 unsigned char *MBEDTLS_PRIVATE(out_msg); /*!< message contents (out_iv+ivlen) */
1599
1600 int MBEDTLS_PRIVATE(out_msgtype); /*!< record header: message type */
1601 size_t MBEDTLS_PRIVATE(out_msglen); /*!< record header: message length */
1602 size_t MBEDTLS_PRIVATE(out_left); /*!< amount of data not yet written */
1603 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1604 size_t MBEDTLS_PRIVATE(out_buf_len); /*!< length of output buffer */
1605 #endif
1606
1607 unsigned char MBEDTLS_PRIVATE(cur_out_ctr)[MBEDTLS_SSL_SEQUENCE_NUMBER_LEN]; /*!< Outgoing record sequence number. */
1608
1609 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1610 uint16_t MBEDTLS_PRIVATE(mtu); /*!< path mtu, used to fragment outgoing messages */
1611 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1612
1613 /*
1614 * PKI layer
1615 */
1616 int MBEDTLS_PRIVATE(client_auth); /*!< flag for client auth. */
1617
1618 /*
1619 * User settings
1620 */
1621 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1622 char *MBEDTLS_PRIVATE(hostname); /*!< expected peer CN for verification
1623 (and SNI if available) */
1624 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1625
1626 #if defined(MBEDTLS_SSL_ALPN)
1627 const char *MBEDTLS_PRIVATE(alpn_chosen); /*!< negotiated protocol */
1628 #endif /* MBEDTLS_SSL_ALPN */
1629
1630 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1631 /*
1632 * use_srtp extension
1633 */
1634 mbedtls_dtls_srtp_info MBEDTLS_PRIVATE(dtls_srtp_info);
1635 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1636
1637 /*
1638 * Information for DTLS hello verify
1639 */
1640 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1641 unsigned char *MBEDTLS_PRIVATE(cli_id); /*!< transport-level ID of the client */
1642 size_t MBEDTLS_PRIVATE(cli_id_len); /*!< length of cli_id */
1643 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
1644
1645 /*
1646 * Secure renegotiation
1647 */
1648 /* needed to know when to send extension on server */
1649 int MBEDTLS_PRIVATE(secure_renegotiation); /*!< does peer support legacy or
1650 secure renegotiation */
1651 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1652 size_t MBEDTLS_PRIVATE(verify_data_len); /*!< length of verify data stored */
1653 char MBEDTLS_PRIVATE(own_verify_data)[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
1654 char MBEDTLS_PRIVATE(peer_verify_data)[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
1655 #endif /* MBEDTLS_SSL_RENEGOTIATION */
1656
1657 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1658 /* CID configuration to use in subsequent handshakes. */
1659
1660 /*! The next incoming CID, chosen by the user and applying to
1661 * all subsequent handshakes. This may be different from the
1662 * CID currently used in case the user has re-configured the CID
1663 * after an initial handshake. */
1664 unsigned char MBEDTLS_PRIVATE(own_cid)[ MBEDTLS_SSL_CID_IN_LEN_MAX ];
1665 uint8_t MBEDTLS_PRIVATE(own_cid_len); /*!< The length of \c own_cid. */
1666 uint8_t MBEDTLS_PRIVATE(negotiate_cid); /*!< This indicates whether the CID extension should
1667 * be negotiated in the next handshake or not.
1668 * Possible values are #MBEDTLS_SSL_CID_ENABLED
1669 * and #MBEDTLS_SSL_CID_DISABLED. */
1670 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1671
1672 /** Callback to export key block and master secret */
1673 mbedtls_ssl_export_keys_t *MBEDTLS_PRIVATE(f_export_keys);
1674 void *MBEDTLS_PRIVATE(p_export_keys); /*!< context for key export callback */
1675 };
1676
1677 /**
1678 * \brief Return the name of the ciphersuite associated with the
1679 * given ID
1680 *
1681 * \param ciphersuite_id SSL ciphersuite ID
1682 *
1683 * \return a string containing the ciphersuite name
1684 */
1685 const char *mbedtls_ssl_get_ciphersuite_name( const int ciphersuite_id );
1686
1687 /**
1688 * \brief Return the ID of the ciphersuite associated with the
1689 * given name
1690 *
1691 * \param ciphersuite_name SSL ciphersuite name
1692 *
1693 * \return the ID with the ciphersuite or 0 if not found
1694 */
1695 int mbedtls_ssl_get_ciphersuite_id( const char *ciphersuite_name );
1696
1697 /**
1698 * \brief Initialize an SSL context
1699 * Just makes the context ready for mbedtls_ssl_setup() or
1700 * mbedtls_ssl_free()
1701 *
1702 * \param ssl SSL context
1703 */
1704 void mbedtls_ssl_init( mbedtls_ssl_context *ssl );
1705
1706 /**
1707 * \brief Set up an SSL context for use
1708 *
1709 * \note No copy of the configuration context is made, it can be
1710 * shared by many mbedtls_ssl_context structures.
1711 *
1712 * \warning The conf structure will be accessed during the session.
1713 * It must not be modified or freed as long as the session
1714 * is active.
1715 *
1716 * \warning This function must be called exactly once per context.
1717 * Calling mbedtls_ssl_setup again is not supported, even
1718 * if no session is active.
1719 *
1720 * \param ssl SSL context
1721 * \param conf SSL configuration to use
1722 *
1723 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED if
1724 * memory allocation failed
1725 */
1726 int mbedtls_ssl_setup( mbedtls_ssl_context *ssl,
1727 const mbedtls_ssl_config *conf );
1728
1729 /**
1730 * \brief Reset an already initialized SSL context for re-use
1731 * while retaining application-set variables, function
1732 * pointers and data.
1733 *
1734 * \param ssl SSL context
1735 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED or
1736 MBEDTLS_ERR_SSL_HW_ACCEL_FAILED
1737 */
1738 int mbedtls_ssl_session_reset( mbedtls_ssl_context *ssl );
1739
1740 /**
1741 * \brief Set the current endpoint type
1742 *
1743 * \param conf SSL configuration
1744 * \param endpoint must be MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
1745 */
1746 void mbedtls_ssl_conf_endpoint( mbedtls_ssl_config *conf, int endpoint );
1747
1748 /**
1749 * \brief Set the transport type (TLS or DTLS).
1750 * Default: TLS
1751 *
1752 * \note For DTLS, you must either provide a recv callback that
1753 * doesn't block, or one that handles timeouts, see
1754 * \c mbedtls_ssl_set_bio(). You also need to provide timer
1755 * callbacks with \c mbedtls_ssl_set_timer_cb().
1756 *
1757 * \param conf SSL configuration
1758 * \param transport transport type:
1759 * MBEDTLS_SSL_TRANSPORT_STREAM for TLS,
1760 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS.
1761 */
1762 void mbedtls_ssl_conf_transport( mbedtls_ssl_config *conf, int transport );
1763
1764 /**
1765 * \brief Set the certificate verification mode
1766 * Default: NONE on server, REQUIRED on client
1767 *
1768 * \param conf SSL configuration
1769 * \param authmode can be:
1770 *
1771 * MBEDTLS_SSL_VERIFY_NONE: peer certificate is not checked
1772 * (default on server)
1773 * (insecure on client)
1774 *
1775 * MBEDTLS_SSL_VERIFY_OPTIONAL: peer certificate is checked, however the
1776 * handshake continues even if verification failed;
1777 * mbedtls_ssl_get_verify_result() can be called after the
1778 * handshake is complete.
1779 *
1780 * MBEDTLS_SSL_VERIFY_REQUIRED: peer *must* present a valid certificate,
1781 * handshake is aborted if verification failed.
1782 * (default on client)
1783 *
1784 * \note On client, MBEDTLS_SSL_VERIFY_REQUIRED is the recommended mode.
1785 * With MBEDTLS_SSL_VERIFY_OPTIONAL, the user needs to call mbedtls_ssl_get_verify_result() at
1786 * the right time(s), which may not be obvious, while REQUIRED always perform
1787 * the verification as soon as possible. For example, REQUIRED was protecting
1788 * against the "triple handshake" attack even before it was found.
1789 */
1790 void mbedtls_ssl_conf_authmode( mbedtls_ssl_config *conf, int authmode );
1791
1792 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1793 /**
1794 * \brief Set the verification callback (Optional).
1795 *
1796 * If set, the provided verify callback is called for each
1797 * certificate in the peer's CRT chain, including the trusted
1798 * root. For more information, please see the documentation of
1799 * \c mbedtls_x509_crt_verify().
1800 *
1801 * \note For per context callbacks and contexts, please use
1802 * mbedtls_ssl_set_verify() instead.
1803 *
1804 * \param conf The SSL configuration to use.
1805 * \param f_vrfy The verification callback to use during CRT verification.
1806 * \param p_vrfy The opaque context to be passed to the callback.
1807 */
1808 void mbedtls_ssl_conf_verify( mbedtls_ssl_config *conf,
1809 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
1810 void *p_vrfy );
1811 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1812
1813 /**
1814 * \brief Set the random number generator callback
1815 *
1816 * \param conf SSL configuration
1817 * \param f_rng RNG function (mandatory)
1818 * \param p_rng RNG parameter
1819 */
1820 void mbedtls_ssl_conf_rng( mbedtls_ssl_config *conf,
1821 int (*f_rng)(void *, unsigned char *, size_t),
1822 void *p_rng );
1823
1824 /**
1825 * \brief Set the debug callback
1826 *
1827 * The callback has the following argument:
1828 * void * opaque context for the callback
1829 * int debug level
1830 * const char * file name
1831 * int line number
1832 * const char * message
1833 *
1834 * \param conf SSL configuration
1835 * \param f_dbg debug function
1836 * \param p_dbg debug parameter
1837 */
1838 void mbedtls_ssl_conf_dbg( mbedtls_ssl_config *conf,
1839 void (*f_dbg)(void *, int, const char *, int, const char *),
1840 void *p_dbg );
1841
1842 /**
1843 * \brief Set the underlying BIO callbacks for write, read and
1844 * read-with-timeout.
1845 *
1846 * \param ssl SSL context
1847 * \param p_bio parameter (context) shared by BIO callbacks
1848 * \param f_send write callback
1849 * \param f_recv read callback
1850 * \param f_recv_timeout blocking read callback with timeout.
1851 *
1852 * \note One of f_recv or f_recv_timeout can be NULL, in which case
1853 * the other is used. If both are non-NULL, f_recv_timeout is
1854 * used and f_recv is ignored (as if it were NULL).
1855 *
1856 * \note The two most common use cases are:
1857 * - non-blocking I/O, f_recv != NULL, f_recv_timeout == NULL
1858 * - blocking I/O, f_recv == NULL, f_recv_timout != NULL
1859 *
1860 * \note For DTLS, you need to provide either a non-NULL
1861 * f_recv_timeout callback, or a f_recv that doesn't block.
1862 *
1863 * \note See the documentations of \c mbedtls_ssl_send_t,
1864 * \c mbedtls_ssl_recv_t and \c mbedtls_ssl_recv_timeout_t for
1865 * the conventions those callbacks must follow.
1866 *
1867 * \note On some platforms, net_sockets.c provides
1868 * \c mbedtls_net_send(), \c mbedtls_net_recv() and
1869 * \c mbedtls_net_recv_timeout() that are suitable to be used
1870 * here.
1871 */
1872 void mbedtls_ssl_set_bio( mbedtls_ssl_context *ssl,
1873 void *p_bio,
1874 mbedtls_ssl_send_t *f_send,
1875 mbedtls_ssl_recv_t *f_recv,
1876 mbedtls_ssl_recv_timeout_t *f_recv_timeout );
1877
1878 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1879
1880 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1881
1882
1883 /**
1884 * \brief Configure the use of the Connection ID (CID)
1885 * extension in the next handshake.
1886 *
1887 * Reference: draft-ietf-tls-dtls-connection-id-05
1888 * https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05
1889 *
1890 * The DTLS CID extension allows the reliable association of
1891 * DTLS records to DTLS connections across changes in the
1892 * underlying transport (changed IP and Port metadata) by
1893 * adding explicit connection identifiers (CIDs) to the
1894 * headers of encrypted DTLS records. The desired CIDs are
1895 * configured by the application layer and are exchanged in
1896 * new `ClientHello` / `ServerHello` extensions during the
1897 * handshake, where each side indicates the CID it wants the
1898 * peer to use when writing encrypted messages. The CIDs are
1899 * put to use once records get encrypted: the stack discards
1900 * any incoming records that don't include the configured CID
1901 * in their header, and adds the peer's requested CID to the
1902 * headers of outgoing messages.
1903 *
1904 * This API enables or disables the use of the CID extension
1905 * in the next handshake and sets the value of the CID to
1906 * be used for incoming messages.
1907 *
1908 * \param ssl The SSL context to configure. This must be initialized.
1909 * \param enable This value determines whether the CID extension should
1910 * be used or not. Possible values are:
1911 * - MBEDTLS_SSL_CID_ENABLED to enable the use of the CID.
1912 * - MBEDTLS_SSL_CID_DISABLED (default) to disable the use
1913 * of the CID.
1914 * \param own_cid The address of the readable buffer holding the CID we want
1915 * the peer to use when sending encrypted messages to us.
1916 * This may be \c NULL if \p own_cid_len is \c 0.
1917 * This parameter is unused if \p enabled is set to
1918 * MBEDTLS_SSL_CID_DISABLED.
1919 * \param own_cid_len The length of \p own_cid.
1920 * This parameter is unused if \p enabled is set to
1921 * MBEDTLS_SSL_CID_DISABLED.
1922 *
1923 * \note The value of \p own_cid_len must match the value of the
1924 * \c len parameter passed to mbedtls_ssl_conf_cid()
1925 * when configuring the ::mbedtls_ssl_config that \p ssl
1926 * is bound to.
1927 *
1928 * \note This CID configuration applies to subsequent handshakes
1929 * performed on the SSL context \p ssl, but does not trigger
1930 * one. You still have to call `mbedtls_ssl_handshake()`
1931 * (for the initial handshake) or `mbedtls_ssl_renegotiate()`
1932 * (for a renegotiation handshake) explicitly after a
1933 * successful call to this function to run the handshake.
1934 *
1935 * \note This call cannot guarantee that the use of the CID
1936 * will be successfully negotiated in the next handshake,
1937 * because the peer might not support it. Specifically:
1938 * - On the Client, enabling the use of the CID through
1939 * this call implies that the `ClientHello` in the next
1940 * handshake will include the CID extension, thereby
1941 * offering the use of the CID to the server. Only if
1942 * the `ServerHello` contains the CID extension, too,
1943 * the CID extension will actually be put to use.
1944 * - On the Server, enabling the use of the CID through
1945 * this call implies that that the server will look for
1946 * the CID extension in a `ClientHello` from the client,
1947 * and, if present, reply with a CID extension in its
1948 * `ServerHello`.
1949 *
1950 * \note To check whether the use of the CID was negotiated
1951 * after the subsequent handshake has completed, please
1952 * use the API mbedtls_ssl_get_peer_cid().
1953 *
1954 * \warning If the use of the CID extension is enabled in this call
1955 * and the subsequent handshake negotiates its use, Mbed TLS
1956 * will silently drop every packet whose CID does not match
1957 * the CID configured in \p own_cid. It is the responsibility
1958 * of the user to adapt the underlying transport to take care
1959 * of CID-based demultiplexing before handing datagrams to
1960 * Mbed TLS.
1961 *
1962 * \return \c 0 on success. In this case, the CID configuration
1963 * applies to the next handshake.
1964 * \return A negative error code on failure.
1965 */
1966 int mbedtls_ssl_set_cid( mbedtls_ssl_context *ssl,
1967 int enable,
1968 unsigned char const *own_cid,
1969 size_t own_cid_len );
1970
1971 /**
1972 * \brief Get information about the use of the CID extension
1973 * in the current connection.
1974 *
1975 * \param ssl The SSL context to query.
1976 * \param enabled The address at which to store whether the CID extension
1977 * is currently in use or not. If the CID is in use,
1978 * `*enabled` is set to MBEDTLS_SSL_CID_ENABLED;
1979 * otherwise, it is set to MBEDTLS_SSL_CID_DISABLED.
1980 * \param peer_cid The address of the buffer in which to store the CID
1981 * chosen by the peer (if the CID extension is used).
1982 * This may be \c NULL in case the value of peer CID
1983 * isn't needed. If it is not \c NULL, \p peer_cid_len
1984 * must not be \c NULL.
1985 * \param peer_cid_len The address at which to store the size of the CID
1986 * chosen by the peer (if the CID extension is used).
1987 * This is also the number of Bytes in \p peer_cid that
1988 * have been written.
1989 * This may be \c NULL in case the length of the peer CID
1990 * isn't needed. If it is \c NULL, \p peer_cid must be
1991 * \c NULL, too.
1992 *
1993 * \note This applies to the state of the CID negotiated in
1994 * the last complete handshake. If a handshake is in
1995 * progress, this function will attempt to complete
1996 * the handshake first.
1997 *
1998 * \note If CID extensions have been exchanged but both client
1999 * and server chose to use an empty CID, this function
2000 * sets `*enabled` to #MBEDTLS_SSL_CID_DISABLED
2001 * (the rationale for this is that the resulting
2002 * communication is the same as if the CID extensions
2003 * hadn't been used).
2004 *
2005 * \return \c 0 on success.
2006 * \return A negative error code on failure.
2007 */
2008 int mbedtls_ssl_get_peer_cid( mbedtls_ssl_context *ssl,
2009 int *enabled,
2010 unsigned char peer_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ],
2011 size_t *peer_cid_len );
2012
2013 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
2014
2015 /**
2016 * \brief Set the Maximum Tranport Unit (MTU).
2017 * Special value: 0 means unset (no limit).
2018 * This represents the maximum size of a datagram payload
2019 * handled by the transport layer (usually UDP) as determined
2020 * by the network link and stack. In practice, this controls
2021 * the maximum size datagram the DTLS layer will pass to the
2022 * \c f_send() callback set using \c mbedtls_ssl_set_bio().
2023 *
2024 * \note The limit on datagram size is converted to a limit on
2025 * record payload by subtracting the current overhead of
2026 * encapsulation and encryption/authentication if any.
2027 *
2028 * \note This can be called at any point during the connection, for
2029 * example when a Path Maximum Transfer Unit (PMTU)
2030 * estimate becomes available from other sources,
2031 * such as lower (or higher) protocol layers.
2032 *
2033 * \note This setting only controls the size of the packets we send,
2034 * and does not restrict the size of the datagrams we're
2035 * willing to receive. Client-side, you can request the
2036 * server to use smaller records with \c
2037 * mbedtls_ssl_conf_max_frag_len().
2038 *
2039 * \note If both a MTU and a maximum fragment length have been
2040 * configured (or negotiated with the peer), the resulting
2041 * lower limit on record payload (see first note) is used.
2042 *
2043 * \note This can only be used to decrease the maximum size
2044 * of datagrams (hence records, see first note) sent. It
2045 * cannot be used to increase the maximum size of records over
2046 * the limit set by #MBEDTLS_SSL_OUT_CONTENT_LEN.
2047 *
2048 * \note Values lower than the current record layer expansion will
2049 * result in an error when trying to send data.
2050 *
2051 * \param ssl SSL context
2052 * \param mtu Value of the path MTU in bytes
2053 */
2054 void mbedtls_ssl_set_mtu( mbedtls_ssl_context *ssl, uint16_t mtu );
2055 #endif /* MBEDTLS_SSL_PROTO_DTLS */
2056
2057 #if defined(MBEDTLS_X509_CRT_PARSE_C)
2058 /**
2059 * \brief Set a connection-specific verification callback (optional).
2060 *
2061 * If set, the provided verify callback is called for each
2062 * certificate in the peer's CRT chain, including the trusted
2063 * root. For more information, please see the documentation of
2064 * \c mbedtls_x509_crt_verify().
2065 *
2066 * \note This call is analogous to mbedtls_ssl_conf_verify() but
2067 * binds the verification callback and context to an SSL context
2068 * as opposed to an SSL configuration.
2069 * If mbedtls_ssl_conf_verify() and mbedtls_ssl_set_verify()
2070 * are both used, mbedtls_ssl_set_verify() takes precedence.
2071 *
2072 * \param ssl The SSL context to use.
2073 * \param f_vrfy The verification callback to use during CRT verification.
2074 * \param p_vrfy The opaque context to be passed to the callback.
2075 */
2076 void mbedtls_ssl_set_verify( mbedtls_ssl_context *ssl,
2077 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2078 void *p_vrfy );
2079 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2080
2081 /**
2082 * \brief Set the timeout period for mbedtls_ssl_read()
2083 * (Default: no timeout.)
2084 *
2085 * \param conf SSL configuration context
2086 * \param timeout Timeout value in milliseconds.
2087 * Use 0 for no timeout (default).
2088 *
2089 * \note With blocking I/O, this will only work if a non-NULL
2090 * \c f_recv_timeout was set with \c mbedtls_ssl_set_bio().
2091 * With non-blocking I/O, this will only work if timer
2092 * callbacks were set with \c mbedtls_ssl_set_timer_cb().
2093 *
2094 * \note With non-blocking I/O, you may also skip this function
2095 * altogether and handle timeouts at the application layer.
2096 */
2097 void mbedtls_ssl_conf_read_timeout( mbedtls_ssl_config *conf, uint32_t timeout );
2098
2099 /**
2100 * \brief Check whether a buffer contains a valid and authentic record
2101 * that has not been seen before. (DTLS only).
2102 *
2103 * This function does not change the user-visible state
2104 * of the SSL context. Its sole purpose is to provide
2105 * an indication of the legitimacy of an incoming record.
2106 *
2107 * This can be useful e.g. in distributed server environments
2108 * using the DTLS Connection ID feature, in which connections
2109 * might need to be passed between service instances on a change
2110 * of peer address, but where such disruptive operations should
2111 * only happen after the validity of incoming records has been
2112 * confirmed.
2113 *
2114 * \param ssl The SSL context to use.
2115 * \param buf The address of the buffer holding the record to be checked.
2116 * This must be a read/write buffer of length \p buflen Bytes.
2117 * \param buflen The length of \p buf in Bytes.
2118 *
2119 * \note This routine only checks whether the provided buffer begins
2120 * with a valid and authentic record that has not been seen
2121 * before, but does not check potential data following the
2122 * initial record. In particular, it is possible to pass DTLS
2123 * datagrams containing multiple records, in which case only
2124 * the first record is checked.
2125 *
2126 * \note This function modifies the input buffer \p buf. If you need
2127 * to preserve the original record, you have to maintain a copy.
2128 *
2129 * \return \c 0 if the record is valid and authentic and has not been
2130 * seen before.
2131 * \return MBEDTLS_ERR_SSL_INVALID_MAC if the check completed
2132 * successfully but the record was found to be not authentic.
2133 * \return MBEDTLS_ERR_SSL_INVALID_RECORD if the check completed
2134 * successfully but the record was found to be invalid for
2135 * a reason different from authenticity checking.
2136 * \return MBEDTLS_ERR_SSL_UNEXPECTED_RECORD if the check completed
2137 * successfully but the record was found to be unexpected
2138 * in the state of the SSL context, including replayed records.
2139 * \return Another negative error code on different kinds of failure.
2140 * In this case, the SSL context becomes unusable and needs
2141 * to be freed or reset before reuse.
2142 */
2143 int mbedtls_ssl_check_record( mbedtls_ssl_context const *ssl,
2144 unsigned char *buf,
2145 size_t buflen );
2146
2147 /**
2148 * \brief Set the timer callbacks (Mandatory for DTLS.)
2149 *
2150 * \param ssl SSL context
2151 * \param p_timer parameter (context) shared by timer callbacks
2152 * \param f_set_timer set timer callback
2153 * \param f_get_timer get timer callback. Must return:
2154 *
2155 * \note See the documentation of \c mbedtls_ssl_set_timer_t and
2156 * \c mbedtls_ssl_get_timer_t for the conventions this pair of
2157 * callbacks must follow.
2158 *
2159 * \note On some platforms, timing.c provides
2160 * \c mbedtls_timing_set_delay() and
2161 * \c mbedtls_timing_get_delay() that are suitable for using
2162 * here, except if using an event-driven style.
2163 *
2164 * \note See also the "DTLS tutorial" article in our knowledge base.
2165 * https://tls.mbed.org/kb/how-to/dtls-tutorial
2166 */
2167 void mbedtls_ssl_set_timer_cb( mbedtls_ssl_context *ssl,
2168 void *p_timer,
2169 mbedtls_ssl_set_timer_t *f_set_timer,
2170 mbedtls_ssl_get_timer_t *f_get_timer );
2171
2172 /**
2173 * \brief Callback type: generate and write session ticket
2174 *
2175 * \note This describes what a callback implementation should do.
2176 * This callback should generate an encrypted and
2177 * authenticated ticket for the session and write it to the
2178 * output buffer. Here, ticket means the opaque ticket part
2179 * of the NewSessionTicket structure of RFC 5077.
2180 *
2181 * \param p_ticket Context for the callback
2182 * \param session SSL session to be written in the ticket
2183 * \param start Start of the output buffer
2184 * \param end End of the output buffer
2185 * \param tlen On exit, holds the length written
2186 * \param lifetime On exit, holds the lifetime of the ticket in seconds
2187 *
2188 * \return 0 if successful, or
2189 * a specific MBEDTLS_ERR_XXX code.
2190 */
2191 typedef int mbedtls_ssl_ticket_write_t( void *p_ticket,
2192 const mbedtls_ssl_session *session,
2193 unsigned char *start,
2194 const unsigned char *end,
2195 size_t *tlen,
2196 uint32_t *lifetime );
2197
2198 /**
2199 * \brief Callback type: parse and load session ticket
2200 *
2201 * \note This describes what a callback implementation should do.
2202 * This callback should parse a session ticket as generated
2203 * by the corresponding mbedtls_ssl_ticket_write_t function,
2204 * and, if the ticket is authentic and valid, load the
2205 * session.
2206 *
2207 * \note The implementation is allowed to modify the first len
2208 * bytes of the input buffer, eg to use it as a temporary
2209 * area for the decrypted ticket contents.
2210 *
2211 * \param p_ticket Context for the callback
2212 * \param session SSL session to be loaded
2213 * \param buf Start of the buffer containing the ticket
2214 * \param len Length of the ticket.
2215 *
2216 * \return 0 if successful, or
2217 * MBEDTLS_ERR_SSL_INVALID_MAC if not authentic, or
2218 * MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED if expired, or
2219 * any other non-zero code for other failures.
2220 */
2221 typedef int mbedtls_ssl_ticket_parse_t( void *p_ticket,
2222 mbedtls_ssl_session *session,
2223 unsigned char *buf,
2224 size_t len );
2225
2226 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
2227 /**
2228 * \brief Configure SSL session ticket callbacks (server only).
2229 * (Default: none.)
2230 *
2231 * \note On server, session tickets are enabled by providing
2232 * non-NULL callbacks.
2233 *
2234 * \note On client, use \c mbedtls_ssl_conf_session_tickets().
2235 *
2236 * \param conf SSL configuration context
2237 * \param f_ticket_write Callback for writing a ticket
2238 * \param f_ticket_parse Callback for parsing a ticket
2239 * \param p_ticket Context shared by the two callbacks
2240 */
2241 void mbedtls_ssl_conf_session_tickets_cb( mbedtls_ssl_config *conf,
2242 mbedtls_ssl_ticket_write_t *f_ticket_write,
2243 mbedtls_ssl_ticket_parse_t *f_ticket_parse,
2244 void *p_ticket );
2245 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
2246
2247 /**
2248 * \brief Configure a key export callback.
2249 * (Default: none.)
2250 *
2251 * This API can be used for two purposes:
2252 * - Debugging: Use this API to e.g. generate an NSSKeylog
2253 * file and use it to inspect encrypted traffic in tools
2254 * such as Wireshark.
2255 * - Application-specific export: Use this API to implement
2256 * key exporters, e.g. for EAP-TLS or DTLS-SRTP.
2257 *
2258 *
2259 * \param ssl The SSL context to which the export
2260 * callback should be attached.
2261 * \param f_export_keys The callback for the key export.
2262 * \param p_export_keys The opaque context pointer to be passed to the
2263 * callback \p f_export_keys.
2264 */
2265 void mbedtls_ssl_set_export_keys_cb( mbedtls_ssl_context *ssl,
2266 mbedtls_ssl_export_keys_t *f_export_keys,
2267 void *p_export_keys );
2268
2269 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
2270 /**
2271 * \brief Configure asynchronous private key operation callbacks.
2272 *
2273 * \param conf SSL configuration context
2274 * \param f_async_sign Callback to start a signature operation. See
2275 * the description of ::mbedtls_ssl_async_sign_t
2276 * for more information. This may be \c NULL if the
2277 * external processor does not support any signature
2278 * operation; in this case the private key object
2279 * associated with the certificate will be used.
2280 * \param f_async_decrypt Callback to start a decryption operation. See
2281 * the description of ::mbedtls_ssl_async_decrypt_t
2282 * for more information. This may be \c NULL if the
2283 * external processor does not support any decryption
2284 * operation; in this case the private key object
2285 * associated with the certificate will be used.
2286 * \param f_async_resume Callback to resume an asynchronous operation. See
2287 * the description of ::mbedtls_ssl_async_resume_t
2288 * for more information. This may not be \c NULL unless
2289 * \p f_async_sign and \p f_async_decrypt are both
2290 * \c NULL.
2291 * \param f_async_cancel Callback to cancel an asynchronous operation. See
2292 * the description of ::mbedtls_ssl_async_cancel_t
2293 * for more information. This may be \c NULL if
2294 * no cleanup is needed.
2295 * \param config_data A pointer to configuration data which can be
2296 * retrieved with
2297 * mbedtls_ssl_conf_get_async_config_data(). The
2298 * library stores this value without dereferencing it.
2299 */
2300 void mbedtls_ssl_conf_async_private_cb( mbedtls_ssl_config *conf,
2301 mbedtls_ssl_async_sign_t *f_async_sign,
2302 mbedtls_ssl_async_decrypt_t *f_async_decrypt,
2303 mbedtls_ssl_async_resume_t *f_async_resume,
2304 mbedtls_ssl_async_cancel_t *f_async_cancel,
2305 void *config_data );
2306
2307 /**
2308 * \brief Retrieve the configuration data set by
2309 * mbedtls_ssl_conf_async_private_cb().
2310 *
2311 * \param conf SSL configuration context
2312 * \return The configuration data set by
2313 * mbedtls_ssl_conf_async_private_cb().
2314 */
2315 void *mbedtls_ssl_conf_get_async_config_data( const mbedtls_ssl_config *conf );
2316
2317 /**
2318 * \brief Retrieve the asynchronous operation user context.
2319 *
2320 * \note This function may only be called while a handshake
2321 * is in progress.
2322 *
2323 * \param ssl The SSL context to access.
2324 *
2325 * \return The asynchronous operation user context that was last
2326 * set during the current handshake. If
2327 * mbedtls_ssl_set_async_operation_data() has not yet been
2328 * called during the current handshake, this function returns
2329 * \c NULL.
2330 */
2331 void *mbedtls_ssl_get_async_operation_data( const mbedtls_ssl_context *ssl );
2332
2333 /**
2334 * \brief Retrieve the asynchronous operation user context.
2335 *
2336 * \note This function may only be called while a handshake
2337 * is in progress.
2338 *
2339 * \param ssl The SSL context to access.
2340 * \param ctx The new value of the asynchronous operation user context.
2341 * Call mbedtls_ssl_get_async_operation_data() later during the
2342 * same handshake to retrieve this value.
2343 */
2344 void mbedtls_ssl_set_async_operation_data( mbedtls_ssl_context *ssl,
2345 void *ctx );
2346 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
2347
2348 /**
2349 * \brief Callback type: generate a cookie
2350 *
2351 * \param ctx Context for the callback
2352 * \param p Buffer to write to,
2353 * must be updated to point right after the cookie
2354 * \param end Pointer to one past the end of the output buffer
2355 * \param info Client ID info that was passed to
2356 * \c mbedtls_ssl_set_client_transport_id()
2357 * \param ilen Length of info in bytes
2358 *
2359 * \return The callback must return 0 on success,
2360 * or a negative error code.
2361 */
2362 typedef int mbedtls_ssl_cookie_write_t( void *ctx,
2363 unsigned char **p, unsigned char *end,
2364 const unsigned char *info, size_t ilen );
2365
2366 /**
2367 * \brief Callback type: verify a cookie
2368 *
2369 * \param ctx Context for the callback
2370 * \param cookie Cookie to verify
2371 * \param clen Length of cookie
2372 * \param info Client ID info that was passed to
2373 * \c mbedtls_ssl_set_client_transport_id()
2374 * \param ilen Length of info in bytes
2375 *
2376 * \return The callback must return 0 if cookie is valid,
2377 * or a negative error code.
2378 */
2379 typedef int mbedtls_ssl_cookie_check_t( void *ctx,
2380 const unsigned char *cookie, size_t clen,
2381 const unsigned char *info, size_t ilen );
2382
2383 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
2384 /**
2385 * \brief Register callbacks for DTLS cookies
2386 * (Server only. DTLS only.)
2387 *
2388 * Default: dummy callbacks that fail, in order to force you to
2389 * register working callbacks (and initialize their context).
2390 *
2391 * To disable HelloVerifyRequest, register NULL callbacks.
2392 *
2393 * \warning Disabling hello verification allows your server to be used
2394 * for amplification in DoS attacks against other hosts.
2395 * Only disable if you known this can't happen in your
2396 * particular environment.
2397 *
2398 * \note See comments on \c mbedtls_ssl_handshake() about handling
2399 * the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected
2400 * on the first handshake attempt when this is enabled.
2401 *
2402 * \note This is also necessary to handle client reconnection from
2403 * the same port as described in RFC 6347 section 4.2.8 (only
2404 * the variant with cookies is supported currently). See
2405 * comments on \c mbedtls_ssl_read() for details.
2406 *
2407 * \param conf SSL configuration
2408 * \param f_cookie_write Cookie write callback
2409 * \param f_cookie_check Cookie check callback
2410 * \param p_cookie Context for both callbacks
2411 */
2412 void mbedtls_ssl_conf_dtls_cookies( mbedtls_ssl_config *conf,
2413 mbedtls_ssl_cookie_write_t *f_cookie_write,
2414 mbedtls_ssl_cookie_check_t *f_cookie_check,
2415 void *p_cookie );
2416
2417 /**
2418 * \brief Set client's transport-level identification info.
2419 * (Server only. DTLS only.)
2420 *
2421 * This is usually the IP address (and port), but could be
2422 * anything identify the client depending on the underlying
2423 * network stack. Used for HelloVerifyRequest with DTLS.
2424 * This is *not* used to route the actual packets.
2425 *
2426 * \param ssl SSL context
2427 * \param info Transport-level info identifying the client (eg IP + port)
2428 * \param ilen Length of info in bytes
2429 *
2430 * \note An internal copy is made, so the info buffer can be reused.
2431 *
2432 * \return 0 on success,
2433 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client,
2434 * MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory.
2435 */
2436 int mbedtls_ssl_set_client_transport_id( mbedtls_ssl_context *ssl,
2437 const unsigned char *info,
2438 size_t ilen );
2439
2440 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
2441
2442 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
2443 /**
2444 * \brief Enable or disable anti-replay protection for DTLS.
2445 * (DTLS only, no effect on TLS.)
2446 * Default: enabled.
2447 *
2448 * \param conf SSL configuration
2449 * \param mode MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED.
2450 *
2451 * \warning Disabling this is a security risk unless the application
2452 * protocol handles duplicated packets in a safe way. You
2453 * should not disable this without careful consideration.
2454 * However, if your application already detects duplicated
2455 * packets and needs information about them to adjust its
2456 * transmission strategy, then you'll want to disable this.
2457 */
2458 void mbedtls_ssl_conf_dtls_anti_replay( mbedtls_ssl_config *conf, char mode );
2459 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
2460
2461 /**
2462 * \brief Set a limit on the number of records with a bad MAC
2463 * before terminating the connection.
2464 * (DTLS only, no effect on TLS.)
2465 * Default: 0 (disabled).
2466 *
2467 * \param conf SSL configuration
2468 * \param limit Limit, or 0 to disable.
2469 *
2470 * \note If the limit is N, then the connection is terminated when
2471 * the Nth non-authentic record is seen.
2472 *
2473 * \note Records with an invalid header are not counted, only the
2474 * ones going through the authentication-decryption phase.
2475 *
2476 * \note This is a security trade-off related to the fact that it's
2477 * often relatively easy for an active attacker ot inject UDP
2478 * datagrams. On one hand, setting a low limit here makes it
2479 * easier for such an attacker to forcibly terminated a
2480 * connection. On the other hand, a high limit or no limit
2481 * might make us waste resources checking authentication on
2482 * many bogus packets.
2483 */
2484 void mbedtls_ssl_conf_dtls_badmac_limit( mbedtls_ssl_config *conf, unsigned limit );
2485
2486 #if defined(MBEDTLS_SSL_PROTO_DTLS)
2487
2488 /**
2489 * \brief Allow or disallow packing of multiple handshake records
2490 * within a single datagram.
2491 *
2492 * \param ssl The SSL context to configure.
2493 * \param allow_packing This determines whether datagram packing may
2494 * be used or not. A value of \c 0 means that every
2495 * record will be sent in a separate datagram; a
2496 * value of \c 1 means that, if space permits,
2497 * multiple handshake messages (including CCS) belonging to
2498 * a single flight may be packed within a single datagram.
2499 *
2500 * \note This is enabled by default and should only be disabled
2501 * for test purposes, or if datagram packing causes
2502 * interoperability issues with peers that don't support it.
2503 *
2504 * \note Allowing datagram packing reduces the network load since
2505 * there's less overhead if multiple messages share the same
2506 * datagram. Also, it increases the handshake efficiency
2507 * since messages belonging to a single datagram will not
2508 * be reordered in transit, and so future message buffering
2509 * or flight retransmission (if no buffering is used) as
2510 * means to deal with reordering are needed less frequently.
2511 *
2512 * \note Application records are not affected by this option and
2513 * are currently always sent in separate datagrams.
2514 *
2515 */
2516 void mbedtls_ssl_set_datagram_packing( mbedtls_ssl_context *ssl,
2517 unsigned allow_packing );
2518
2519 /**
2520 * \brief Set retransmit timeout values for the DTLS handshake.
2521 * (DTLS only, no effect on TLS.)
2522 *
2523 * \param conf SSL configuration
2524 * \param min Initial timeout value in milliseconds.
2525 * Default: 1000 (1 second).
2526 * \param max Maximum timeout value in milliseconds.
2527 * Default: 60000 (60 seconds).
2528 *
2529 * \note Default values are from RFC 6347 section 4.2.4.1.
2530 *
2531 * \note The 'min' value should typically be slightly above the
2532 * expected round-trip time to your peer, plus whatever time
2533 * it takes for the peer to process the message. For example,
2534 * if your RTT is about 600ms and you peer needs up to 1s to
2535 * do the cryptographic operations in the handshake, then you
2536 * should set 'min' slightly above 1600. Lower values of 'min'
2537 * might cause spurious resends which waste network resources,
2538 * while larger value of 'min' will increase overall latency
2539 * on unreliable network links.
2540 *
2541 * \note The more unreliable your network connection is, the larger
2542 * your max / min ratio needs to be in order to achieve
2543 * reliable handshakes.
2544 *
2545 * \note Messages are retransmitted up to log2(ceil(max/min)) times.
2546 * For example, if min = 1s and max = 5s, the retransmit plan
2547 * goes: send ... 1s -> resend ... 2s -> resend ... 4s ->
2548 * resend ... 5s -> give up and return a timeout error.
2549 */
2550 void mbedtls_ssl_conf_handshake_timeout( mbedtls_ssl_config *conf, uint32_t min, uint32_t max );
2551 #endif /* MBEDTLS_SSL_PROTO_DTLS */
2552
2553 #if defined(MBEDTLS_SSL_SRV_C)
2554 /**
2555 * \brief Set the session cache callbacks (server-side only)
2556 * If not set, no session resuming is done (except if session
2557 * tickets are enabled too).
2558 *
2559 * The session cache has the responsibility to check for stale
2560 * entries based on timeout. See RFC 5246 for recommendations.
2561 *
2562 * Warning: session.peer_cert is cleared by the SSL/TLS layer on
2563 * connection shutdown, so do not cache the pointer! Either set
2564 * it to NULL or make a full copy of the certificate.
2565 *
2566 * The get callback is called once during the initial handshake
2567 * to enable session resuming. The get function has the
2568 * following parameters: (void *parameter, mbedtls_ssl_session *session)
2569 * If a valid entry is found, it should fill the master of
2570 * the session object with the cached values and return 0,
2571 * return 1 otherwise. Optionally peer_cert can be set as well
2572 * if it is properly present in cache entry.
2573 *
2574 * The set callback is called once during the initial handshake
2575 * to enable session resuming after the entire handshake has
2576 * been finished. The set function has the following parameters:
2577 * (void *parameter, const mbedtls_ssl_session *session). The function
2578 * should create a cache entry for future retrieval based on
2579 * the data in the session structure and should keep in mind
2580 * that the mbedtls_ssl_session object presented (and all its referenced
2581 * data) is cleared by the SSL/TLS layer when the connection is
2582 * terminated. It is recommended to add metadata to determine if
2583 * an entry is still valid in the future. Return 0 if
2584 * successfully cached, return 1 otherwise.
2585 *
2586 * \param conf SSL configuration
2587 * \param p_cache parmater (context) for both callbacks
2588 * \param f_get_cache session get callback
2589 * \param f_set_cache session set callback
2590 */
2591 void mbedtls_ssl_conf_session_cache( mbedtls_ssl_config *conf,
2592 void *p_cache,
2593 mbedtls_ssl_cache_get_t *f_get_cache,
2594 mbedtls_ssl_cache_set_t *f_set_cache );
2595 #endif /* MBEDTLS_SSL_SRV_C */
2596
2597 #if defined(MBEDTLS_SSL_CLI_C)
2598 /**
2599 * \brief Load a session for session resumption.
2600 *
2601 * Sessions loaded through this call will be considered
2602 * for session resumption in the next handshake.
2603 *
2604 * \note Even if this call succeeds, it is not guaranteed that
2605 * the next handshake will indeed be shortened through the
2606 * use of session resumption: The server is always free
2607 * to reject any attempt for resumption and fall back to
2608 * a full handshake.
2609 *
2610 * \note This function can handle a variety of mechanisms for session
2611 * resumption: For TLS 1.2, both session ID-based resumption and
2612 * ticket-based resumption will be considered. For TLS 1.3,
2613 * once implemented, sessions equate to tickets, and loading
2614 * one or more sessions via this call will lead to their
2615 * corresponding tickets being advertised as resumption PSKs
2616 * by the client.
2617 *
2618 * \note Calling this function multiple times will only be useful
2619 * once TLS 1.3 is supported. For TLS 1.2 connections, this
2620 * function should be called at most once.
2621 *
2622 * \param ssl The SSL context representing the connection which should
2623 * be attempted to be setup using session resumption. This
2624 * must be initialized via mbedtls_ssl_init() and bound to
2625 * an SSL configuration via mbedtls_ssl_setup(), but
2626 * the handshake must not yet have been started.
2627 * \param session The session to be considered for session resumption.
2628 * This must be a session previously exported via
2629 * mbedtls_ssl_get_session(), and potentially serialized and
2630 * deserialized through mbedtls_ssl_session_save() and
2631 * mbedtls_ssl_session_load() in the meantime.
2632 *
2633 * \return \c 0 if successful.
2634 * \return \c MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if the session
2635 * could not be loaded because of an implementation limitation.
2636 * This error is non-fatal, and has no observable effect on
2637 * the SSL context or the session that was attempted to be loaded.
2638 * \return Another negative error code on other kinds of failure.
2639 *
2640 * \sa mbedtls_ssl_get_session()
2641 * \sa mbedtls_ssl_session_load()
2642 */
2643 int mbedtls_ssl_set_session( mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session );
2644 #endif /* MBEDTLS_SSL_CLI_C */
2645
2646 /**
2647 * \brief Load serialized session data into a session structure.
2648 * On client, this can be used for loading saved sessions
2649 * before resuming them with mbedstls_ssl_set_session().
2650 * On server, this can be used for alternative implementations
2651 * of session cache or session tickets.
2652 *
2653 * \warning If a peer certificate chain is associated with the session,
2654 * the serialized state will only contain the peer's
2655 * end-entity certificate and the result of the chain
2656 * verification (unless verification was disabled), but not
2657 * the rest of the chain.
2658 *
2659 * \see mbedtls_ssl_session_save()
2660 * \see mbedtls_ssl_set_session()
2661 *
2662 * \param session The session structure to be populated. It must have been
2663 * initialised with mbedtls_ssl_session_init() but not
2664 * populated yet.
2665 * \param buf The buffer holding the serialized session data. It must be a
2666 * readable buffer of at least \p len bytes.
2667 * \param len The size of the serialized data in bytes.
2668 *
2669 * \return \c 0 if successful.
2670 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
2671 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
2672 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
2673 * was generated in a different version or configuration of
2674 * Mbed TLS.
2675 * \return Another negative value for other kinds of errors (for
2676 * example, unsupported features in the embedded certificate).
2677 */
2678 int mbedtls_ssl_session_load( mbedtls_ssl_session *session,
2679 const unsigned char *buf,
2680 size_t len );
2681
2682 /**
2683 * \brief Save session structure as serialized data in a buffer.
2684 * On client, this can be used for saving session data,
2685 * potentially in non-volatile storage, for resuming later.
2686 * On server, this can be used for alternative implementations
2687 * of session cache or session tickets.
2688 *
2689 * \see mbedtls_ssl_session_load()
2690 *
2691 * \param session The session structure to be saved.
2692 * \param buf The buffer to write the serialized data to. It must be a
2693 * writeable buffer of at least \p len bytes, or may be \c
2694 * NULL if \p len is \c 0.
2695 * \param buf_len The number of bytes available for writing in \p buf.
2696 * \param olen The size in bytes of the data that has been or would have
2697 * been written. It must point to a valid \c size_t.
2698 *
2699 * \note \p olen is updated to the correct value regardless of
2700 * whether \p buf_len was large enough. This makes it possible
2701 * to determine the necessary size by calling this function
2702 * with \p buf set to \c NULL and \p buf_len to \c 0.
2703 *
2704 * \return \c 0 if successful.
2705 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
2706 */
2707 int mbedtls_ssl_session_save( const mbedtls_ssl_session *session,
2708 unsigned char *buf,
2709 size_t buf_len,
2710 size_t *olen );
2711
2712 /**
2713 * \brief Set the list of allowed ciphersuites and the preference
2714 * order. First in the list has the highest preference.
2715 *
2716 * For TLS 1.2, the notion of ciphersuite determines both
2717 * the key exchange mechanism and the suite of symmetric
2718 * algorithms to be used during and after the handshake.
2719 *
2720 * For TLS 1.3 (in development), the notion of ciphersuite
2721 * only determines the suite of symmetric algorithms to be
2722 * used during and after the handshake, while key exchange
2723 * mechanisms are configured separately.
2724 *
2725 * In Mbed TLS, ciphersuites for both TLS 1.2 and TLS 1.3
2726 * are configured via this function. For users of TLS 1.3,
2727 * there will be separate API for the configuration of key
2728 * exchange mechanisms.
2729 *
2730 * The list of ciphersuites passed to this function may
2731 * contain a mixture of TLS 1.2 and TLS 1.3 ciphersuite
2732 * identifiers. This is useful if negotiation of TLS 1.3
2733 * should be attempted, but a fallback to TLS 1.2 would
2734 * be tolerated.
2735 *
2736 * \note By default, the server chooses its preferred
2737 * ciphersuite among those that the client supports. If
2738 * mbedtls_ssl_conf_preference_order() is called to prefer
2739 * the client's preferences, the server instead chooses
2740 * the client's preferred ciphersuite among those that
2741 * the server supports.
2742 *
2743 * \warning The ciphersuites array \p ciphersuites is not copied.
2744 * It must remain valid for the lifetime of the SSL
2745 * configuration \p conf.
2746 *
2747 * \param conf The SSL configuration to modify.
2748 * \param ciphersuites A 0-terminated list of IANA identifiers of supported
2749 * ciphersuites, accessible through \c MBEDTLS_TLS_XXX
2750 * and \c MBEDTLS_TLS1_3_XXX macros defined in
2751 * ssl_ciphersuites.h.
2752 */
2753 void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf,
2754 const int *ciphersuites );
2755
2756 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
2757 /**
2758 * \brief Set the supported key exchange modes for TLS 1.3 connections.
2759 *
2760 * In contrast to TLS 1.2, the ciphersuite concept in TLS 1.3 does not
2761 * include the choice of key exchange mechanism. It is therefore not
2762 * covered by the API mbedtls_ssl_conf_ciphersuites(). See the
2763 * documentation of mbedtls_ssl_conf_ciphersuites() for more
2764 * information on the ciphersuite concept in TLS 1.2 and TLS 1.3.
2765 *
2766 * The present function is specific to TLS 1.3 and allows users to
2767 * configure the set of supported key exchange mechanisms in TLS 1.3.
2768 *
2769 * \param conf The SSL configuration the change should apply to.
2770 * \param kex_modes A bitwise combination of one or more of the following:
2771 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK
2772 * This flag enables pure-PSK key exchanges.
2773 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL
2774 * This flag enables combined PSK-ephemeral key exchanges.
2775 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL
2776 * This flag enables pure-ephemeral key exchanges.
2777 * For convenience, the following pre-defined macros are
2778 * available for combinations of the above:
2779 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_ALL
2780 * Includes all of pure-PSK, PSK-ephemeral and pure-ephemeral.
2781 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL
2782 * Includes both pure-PSK and combined PSK-ephemeral
2783 * key exchanges, but excludes pure-ephemeral key exchanges.
2784 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL
2785 * Includes both pure-ephemeral and combined PSK-ephemeral
2786 * key exchanges.
2787 *
2788 * \note If a PSK-based key exchange mode shall be supported, applications
2789 * must also use the APIs mbedtls_ssl_conf_psk() or
2790 * mbedtls_ssl_conf_psk_cb() or mbedtls_ssl_conf_psk_opaque()
2791 * to configure the PSKs to be used.
2792 *
2793 * \note If a pure-ephemeral key exchange mode shall be supported,
2794 * server-side applications must also provide a certificate via
2795 * mbedtls_ssl_conf_own_cert().
2796 *
2797 */
2798
2799 void mbedtls_ssl_conf_tls13_key_exchange_modes( mbedtls_ssl_config* conf,
2800 const int kex_modes );
2801 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
2802
2803 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
2804 #define MBEDTLS_SSL_UNEXPECTED_CID_IGNORE 0
2805 #define MBEDTLS_SSL_UNEXPECTED_CID_FAIL 1
2806 /**
2807 * \brief Specify the length of Connection IDs for incoming
2808 * encrypted DTLS records, as well as the behaviour
2809 * on unexpected CIDs.
2810 *
2811 * By default, the CID length is set to \c 0,
2812 * and unexpected CIDs are silently ignored.
2813 *
2814 * \param conf The SSL configuration to modify.
2815 * \param len The length in Bytes of the CID fields in encrypted
2816 * DTLS records using the CID mechanism. This must
2817 * not be larger than #MBEDTLS_SSL_CID_OUT_LEN_MAX.
2818 * \param ignore_other_cids This determines the stack's behaviour when
2819 * receiving a record with an unexpected CID.
2820 * Possible values are:
2821 * - #MBEDTLS_SSL_UNEXPECTED_CID_IGNORE
2822 * In this case, the record is silently ignored.
2823 * - #MBEDTLS_SSL_UNEXPECTED_CID_FAIL
2824 * In this case, the stack fails with the specific
2825 * error code #MBEDTLS_ERR_SSL_UNEXPECTED_CID.
2826 *
2827 * \note The CID specification allows implementations to either
2828 * use a common length for all incoming connection IDs or
2829 * allow variable-length incoming IDs. Mbed TLS currently
2830 * requires a common length for all connections sharing the
2831 * same SSL configuration; this allows simpler parsing of
2832 * record headers.
2833 *
2834 * \return \c 0 on success.
2835 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if \p own_cid_len
2836 * is too large.
2837 */
2838 int mbedtls_ssl_conf_cid( mbedtls_ssl_config *conf, size_t len,
2839 int ignore_other_cids );
2840 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
2841
2842 #if defined(MBEDTLS_X509_CRT_PARSE_C)
2843 /**
2844 * \brief Set the X.509 security profile used for verification
2845 *
2846 * \note The restrictions are enforced for all certificates in the
2847 * chain. However, signatures in the handshake are not covered
2848 * by this setting but by \b mbedtls_ssl_conf_sig_hashes().
2849 *
2850 * \param conf SSL configuration
2851 * \param profile Profile to use
2852 */
2853 void mbedtls_ssl_conf_cert_profile( mbedtls_ssl_config *conf,
2854 const mbedtls_x509_crt_profile *profile );
2855
2856 /**
2857 * \brief Set the data required to verify peer certificate
2858 *
2859 * \note See \c mbedtls_x509_crt_verify() for notes regarding the
2860 * parameters ca_chain (maps to trust_ca for that function)
2861 * and ca_crl.
2862 *
2863 * \param conf SSL configuration
2864 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
2865 * \param ca_crl trusted CA CRLs
2866 */
2867 void mbedtls_ssl_conf_ca_chain( mbedtls_ssl_config *conf,
2868 mbedtls_x509_crt *ca_chain,
2869 mbedtls_x509_crl *ca_crl );
2870
2871 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
2872 /**
2873 * \brief Set the trusted certificate callback.
2874 *
2875 * This API allows to register the set of trusted certificates
2876 * through a callback, instead of a linked list as configured
2877 * by mbedtls_ssl_conf_ca_chain().
2878 *
2879 * This is useful for example in contexts where a large number
2880 * of CAs are used, and the inefficiency of maintaining them
2881 * in a linked list cannot be tolerated. It is also useful when
2882 * the set of trusted CAs needs to be modified frequently.
2883 *
2884 * See the documentation of `mbedtls_x509_crt_ca_cb_t` for
2885 * more information.
2886 *
2887 * \param conf The SSL configuration to register the callback with.
2888 * \param f_ca_cb The trusted certificate callback to use when verifying
2889 * certificate chains.
2890 * \param p_ca_cb The context to be passed to \p f_ca_cb (for example,
2891 * a reference to a trusted CA database).
2892 *
2893 * \note This API is incompatible with mbedtls_ssl_conf_ca_chain():
2894 * Any call to this function overwrites the values set through
2895 * earlier calls to mbedtls_ssl_conf_ca_chain() or
2896 * mbedtls_ssl_conf_ca_cb().
2897 *
2898 * \note This API is incompatible with CA indication in
2899 * CertificateRequest messages: A server-side SSL context which
2900 * is bound to an SSL configuration that uses a CA callback
2901 * configured via mbedtls_ssl_conf_ca_cb(), and which requires
2902 * client authentication, will send an empty CA list in the
2903 * corresponding CertificateRequest message.
2904 *
2905 * \note This API is incompatible with mbedtls_ssl_set_hs_ca_chain():
2906 * If an SSL context is bound to an SSL configuration which uses
2907 * CA callbacks configured via mbedtls_ssl_conf_ca_cb(), then
2908 * calls to mbedtls_ssl_set_hs_ca_chain() have no effect.
2909 *
2910 * \note The use of this API disables the use of restartable ECC
2911 * during X.509 CRT signature verification (but doesn't affect
2912 * other uses).
2913 *
2914 * \warning This API is incompatible with the use of CRLs. Any call to
2915 * mbedtls_ssl_conf_ca_cb() unsets CRLs configured through
2916 * earlier calls to mbedtls_ssl_conf_ca_chain().
2917 *
2918 * \warning In multi-threaded environments, the callback \p f_ca_cb
2919 * must be thread-safe, and it is the user's responsibility
2920 * to guarantee this (for example through a mutex
2921 * contained in the callback context pointed to by \p p_ca_cb).
2922 */
2923 void mbedtls_ssl_conf_ca_cb( mbedtls_ssl_config *conf,
2924 mbedtls_x509_crt_ca_cb_t f_ca_cb,
2925 void *p_ca_cb );
2926 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
2927
2928 /**
2929 * \brief Set own certificate chain and private key
2930 *
2931 * \note own_cert should contain in order from the bottom up your
2932 * certificate chain. The top certificate (self-signed)
2933 * can be omitted.
2934 *
2935 * \note On server, this function can be called multiple times to
2936 * provision more than one cert/key pair (eg one ECDSA, one
2937 * RSA with SHA-256, one RSA with SHA-1). An adequate
2938 * certificate will be selected according to the client's
2939 * advertised capabilities. In case multiple certificates are
2940 * adequate, preference is given to the one set by the first
2941 * call to this function, then second, etc.
2942 *
2943 * \note On client, only the first call has any effect. That is,
2944 * only one client certificate can be provisioned. The
2945 * server's preferences in its CertficateRequest message will
2946 * be ignored and our only cert will be sent regardless of
2947 * whether it matches those preferences - the server can then
2948 * decide what it wants to do with it.
2949 *
2950 * \note The provided \p pk_key needs to match the public key in the
2951 * first certificate in \p own_cert, or all handshakes using
2952 * that certificate will fail. It is your responsibility
2953 * to ensure that; this function will not perform any check.
2954 * You may use mbedtls_pk_check_pair() in order to perform
2955 * this check yourself, but be aware that this function can
2956 * be computationally expensive on some key types.
2957 *
2958 * \param conf SSL configuration
2959 * \param own_cert own public certificate chain
2960 * \param pk_key own private key
2961 *
2962 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
2963 */
2964 int mbedtls_ssl_conf_own_cert( mbedtls_ssl_config *conf,
2965 mbedtls_x509_crt *own_cert,
2966 mbedtls_pk_context *pk_key );
2967 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2968
2969 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
2970 /**
2971 * \brief Configure pre-shared keys (PSKs) and their
2972 * identities to be used in PSK-based ciphersuites.
2973 *
2974 * Only one PSK can be registered, through either
2975 * mbedtls_ssl_conf_psk() or mbedtls_ssl_conf_psk_opaque().
2976 * If you attempt to register more than one PSK, this function
2977 * fails, though this may change in future versions, which
2978 * may add support for multiple PSKs.
2979 *
2980 * \note This is mainly useful for clients. Servers will usually
2981 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
2982 *
2983 * \note A PSK set by \c mbedtls_ssl_set_hs_psk() in the PSK callback
2984 * takes precedence over a PSK configured by this function.
2985 *
2986 * \param conf The SSL configuration to register the PSK with.
2987 * \param psk The pointer to the pre-shared key to use.
2988 * \param psk_len The length of the pre-shared key in bytes.
2989 * \param psk_identity The pointer to the pre-shared key identity.
2990 * \param psk_identity_len The length of the pre-shared key identity
2991 * in bytes.
2992 *
2993 * \note The PSK and its identity are copied internally and
2994 * hence need not be preserved by the caller for the lifetime
2995 * of the SSL configuration.
2996 *
2997 * \return \c 0 if successful.
2998 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no more PSKs
2999 * can be configured. In this case, the old PSK(s) remain intact.
3000 * \return Another negative error code on other kinds of failure.
3001 */
3002 int mbedtls_ssl_conf_psk( mbedtls_ssl_config *conf,
3003 const unsigned char *psk, size_t psk_len,
3004 const unsigned char *psk_identity, size_t psk_identity_len );
3005
3006 #if defined(MBEDTLS_USE_PSA_CRYPTO)
3007 /**
3008 * \brief Configure one or more opaque pre-shared keys (PSKs) and
3009 * their identities to be used in PSK-based ciphersuites.
3010 *
3011 * Only one PSK can be registered, through either
3012 * mbedtls_ssl_conf_psk() or mbedtls_ssl_conf_psk_opaque().
3013 * If you attempt to register more than one PSK, this function
3014 * fails, though this may change in future versions, which
3015 * may add support for multiple PSKs.
3016 *
3017 * \note This is mainly useful for clients. Servers will usually
3018 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
3019 *
3020 * \note An opaque PSK set by \c mbedtls_ssl_set_hs_psk_opaque() in
3021 * the PSK callback takes precedence over an opaque PSK
3022 * configured by this function.
3023 *
3024 * \param conf The SSL configuration to register the PSK with.
3025 * \param psk The identifier of the key slot holding the PSK.
3026 * Until \p conf is destroyed or this function is successfully
3027 * called again, the key slot \p psk must be populated with a
3028 * key of type PSA_ALG_CATEGORY_KEY_DERIVATION whose policy
3029 * allows its use for the key derivation algorithm applied
3030 * in the handshake.
3031 * \param psk_identity The pointer to the pre-shared key identity.
3032 * \param psk_identity_len The length of the pre-shared key identity
3033 * in bytes.
3034 *
3035 * \note The PSK identity hint is copied internally and hence need
3036 * not be preserved by the caller for the lifetime of the
3037 * SSL configuration.
3038 *
3039 * \return \c 0 if successful.
3040 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no more PSKs
3041 * can be configured. In this case, the old PSK(s) remain intact.
3042 * \return Another negative error code on other kinds of failure.
3043 */
3044 int mbedtls_ssl_conf_psk_opaque( mbedtls_ssl_config *conf,
3045 psa_key_id_t psk,
3046 const unsigned char *psk_identity,
3047 size_t psk_identity_len );
3048 #endif /* MBEDTLS_USE_PSA_CRYPTO */
3049
3050 /**
3051 * \brief Set the pre-shared Key (PSK) for the current handshake.
3052 *
3053 * \note This should only be called inside the PSK callback,
3054 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
3055 *
3056 * \note A PSK set by this function takes precedence over a PSK
3057 * configured by \c mbedtls_ssl_conf_psk().
3058 *
3059 * \param ssl The SSL context to configure a PSK for.
3060 * \param psk The pointer to the pre-shared key.
3061 * \param psk_len The length of the pre-shared key in bytes.
3062 *
3063 * \return \c 0 if successful.
3064 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
3065 */
3066 int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl,
3067 const unsigned char *psk, size_t psk_len );
3068
3069 #if defined(MBEDTLS_USE_PSA_CRYPTO)
3070 /**
3071 * \brief Set an opaque pre-shared Key (PSK) for the current handshake.
3072 *
3073 * \note This should only be called inside the PSK callback,
3074 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
3075 *
3076 * \note An opaque PSK set by this function takes precedence over an
3077 * opaque PSK configured by \c mbedtls_ssl_conf_psk_opaque().
3078 *
3079 * \param ssl The SSL context to configure a PSK for.
3080 * \param psk The identifier of the key slot holding the PSK.
3081 * For the duration of the current handshake, the key slot
3082 * must be populated with a key of type
3083 * PSA_ALG_CATEGORY_KEY_DERIVATION whose policy allows its
3084 * use for the key derivation algorithm
3085 * applied in the handshake.
3086 *
3087 * \return \c 0 if successful.
3088 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
3089 */
3090 int mbedtls_ssl_set_hs_psk_opaque( mbedtls_ssl_context *ssl,
3091 psa_key_id_t psk );
3092 #endif /* MBEDTLS_USE_PSA_CRYPTO */
3093
3094 /**
3095 * \brief Set the PSK callback (server-side only).
3096 *
3097 * If set, the PSK callback is called for each
3098 * handshake where a PSK-based ciphersuite was negotiated.
3099 * The caller provides the identity received and wants to
3100 * receive the actual PSK data and length.
3101 *
3102 * The callback has the following parameters:
3103 * - \c void*: The opaque pointer \p p_psk.
3104 * - \c mbedtls_ssl_context*: The SSL context to which
3105 * the operation applies.
3106 * - \c const unsigned char*: The PSK identity
3107 * selected by the client.
3108 * - \c size_t: The length of the PSK identity
3109 * selected by the client.
3110 *
3111 * If a valid PSK identity is found, the callback should use
3112 * \c mbedtls_ssl_set_hs_psk() or
3113 * \c mbedtls_ssl_set_hs_psk_opaque()
3114 * on the SSL context to set the correct PSK and return \c 0.
3115 * Any other return value will result in a denied PSK identity.
3116 *
3117 * \note A dynamic PSK (i.e. set by the PSK callback) takes
3118 * precedence over a static PSK (i.e. set by
3119 * \c mbedtls_ssl_conf_psk() or
3120 * \c mbedtls_ssl_conf_psk_opaque()).
3121 * This means that if you set a PSK callback using this
3122 * function, you don't need to set a PSK using
3123 * \c mbedtls_ssl_conf_psk() or
3124 * \c mbedtls_ssl_conf_psk_opaque()).
3125 *
3126 * \param conf The SSL configuration to register the callback with.
3127 * \param f_psk The callback for selecting and setting the PSK based
3128 * in the PSK identity chosen by the client.
3129 * \param p_psk A pointer to an opaque structure to be passed to
3130 * the callback, for example a PSK store.
3131 */
3132 void mbedtls_ssl_conf_psk_cb( mbedtls_ssl_config *conf,
3133 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *,
3134 size_t),
3135 void *p_psk );
3136 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
3137
3138 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
3139 /**
3140 * \brief Set the Diffie-Hellman public P and G values
3141 * from big-endian binary presentations.
3142 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN)
3143 *
3144 * \param conf SSL configuration
3145 * \param dhm_P Diffie-Hellman-Merkle modulus in big-endian binary form
3146 * \param P_len Length of DHM modulus
3147 * \param dhm_G Diffie-Hellman-Merkle generator in big-endian binary form
3148 * \param G_len Length of DHM generator
3149 *
3150 * \return 0 if successful
3151 */
3152 int mbedtls_ssl_conf_dh_param_bin( mbedtls_ssl_config *conf,
3153 const unsigned char *dhm_P, size_t P_len,
3154 const unsigned char *dhm_G, size_t G_len );
3155
3156 /**
3157 * \brief Set the Diffie-Hellman public P and G values,
3158 * read from existing context (server-side only)
3159 *
3160 * \param conf SSL configuration
3161 * \param dhm_ctx Diffie-Hellman-Merkle context
3162 *
3163 * \return 0 if successful
3164 */
3165 int mbedtls_ssl_conf_dh_param_ctx( mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx );
3166 #endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */
3167
3168 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
3169 /**
3170 * \brief Set the minimum length for Diffie-Hellman parameters.
3171 * (Client-side only.)
3172 * (Default: 1024 bits.)
3173 *
3174 * \param conf SSL configuration
3175 * \param bitlen Minimum bit length of the DHM prime
3176 */
3177 void mbedtls_ssl_conf_dhm_min_bitlen( mbedtls_ssl_config *conf,
3178 unsigned int bitlen );
3179 #endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */
3180
3181 #if defined(MBEDTLS_ECP_C)
3182 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
3183 /**
3184 * \brief Set the allowed curves in order of preference.
3185 *
3186 * On server: this only affects selection of the ECDHE curve;
3187 * the curves used for ECDH and ECDSA are determined by the
3188 * list of available certificates instead.
3189 *
3190 * On client: this affects the list of curves offered for any
3191 * use. The server can override our preference order.
3192 *
3193 * Both sides: limits the set of curves accepted for use in
3194 * ECDHE and in the peer's end-entity certificate.
3195 *
3196 * \deprecated Superseeded by mbedtls_ssl_conf_groups().
3197 *
3198 * \note This has no influence on which curves are allowed inside the
3199 * certificate chains, see \c mbedtls_ssl_conf_cert_profile()
3200 * for that. For the end-entity certificate however, the key
3201 * will be accepted only if it is allowed both by this list
3202 * and by the cert profile.
3203 *
3204 * \note This list should be ordered by decreasing preference
3205 * (preferred curve first).
3206 *
3207 * \note The default list is the same set of curves that
3208 * #mbedtls_x509_crt_profile_default allows, plus
3209 * ECDHE-only curves selected according to the same criteria.
3210 * The order favors curves with the lowest resource usage.
3211 *
3212 * \note New minor versions of Mbed TLS may extend this list,
3213 * for example if new curves are added to the library.
3214 * New minor versions of Mbed TLS will not remove items
3215 * from this list unless serious security concerns require it.
3216 * New minor versions of Mbed TLS may change the order in
3217 * keeping with the general principle of favoring the lowest
3218 * resource usage.
3219 *
3220 * \param conf SSL configuration
3221 * \param curves Ordered list of allowed curves,
3222 * terminated by MBEDTLS_ECP_DP_NONE.
3223 */
3224 void MBEDTLS_DEPRECATED mbedtls_ssl_conf_curves( mbedtls_ssl_config *conf,
3225 const mbedtls_ecp_group_id *curves );
3226 #endif /* MBEDTLS_DEPRECATED_REMOVED */
3227 #endif /* MBEDTLS_ECP_C */
3228
3229 /**
3230 * \brief Set the allowed groups in order of preference.
3231 *
3232 * On server: This only affects the choice of key agreement mechanism
3233 *
3234 * On client: this affects the list of groups offered for any
3235 * use. The server can override our preference order.
3236 *
3237 * Both sides: limits the set of groups accepted for use in
3238 * key sharing.
3239 *
3240 * \note This function replaces the deprecated mbedtls_ssl_conf_curves(),
3241 * which only allows ECP curves to be configured.
3242 *
3243 * \note The most recent invocation of either mbedtls_ssl_conf_curves()
3244 * or mbedtls_ssl_conf_groups() nullifies all previous invocations
3245 * of both.
3246 *
3247 * \note This list should be ordered by decreasing preference
3248 * (preferred group first).
3249 *
3250 * \note When this function is not called, a default list is used,
3251 * consisting of all supported curves at 255 bits and above,
3252 * and all supported finite fields at 2048 bits and above.
3253 * The order favors groups with the lowest resource usage.
3254 *
3255 * \note New minor versions of Mbed TLS will not remove items
3256 * from the default list unless serious security concerns require it.
3257 * New minor versions of Mbed TLS may change the order in
3258 * keeping with the general principle of favoring the lowest
3259 * resource usage.
3260 *
3261 * \param conf SSL configuration
3262 * \param groups List of allowed groups ordered by preference, terminated by 0.
3263 * Must contain valid IANA NamedGroup IDs (provided via either an integer
3264 * or using MBEDTLS_TLS1_3_NAMED_GROUP_XXX macros).
3265 */
3266 void mbedtls_ssl_conf_groups( mbedtls_ssl_config *conf,
3267 const uint16_t *groups );
3268
3269 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
3270 /**
3271 * \brief Set the allowed hashes for signatures during the handshake.
3272 *
3273 * \note This only affects which hashes are offered and can be used
3274 * for signatures during the handshake. Hashes for message
3275 * authentication and the TLS PRF are controlled by the
3276 * ciphersuite, see \c mbedtls_ssl_conf_ciphersuites(). Hashes
3277 * used for certificate signature are controlled by the
3278 * verification profile, see \c mbedtls_ssl_conf_cert_profile().
3279 *
3280 * \note This list should be ordered by decreasing preference
3281 * (preferred hash first).
3282 *
3283 * \note By default, all supported hashes whose length is at least
3284 * 256 bits are allowed. This is the same set as the default
3285 * for certificate verification
3286 * (#mbedtls_x509_crt_profile_default).
3287 * The preference order is currently unspecified and may
3288 * change in future versions.
3289 *
3290 * \note New minor versions of Mbed TLS may extend this list,
3291 * for example if new curves are added to the library.
3292 * New minor versions of Mbed TLS will not remove items
3293 * from this list unless serious security concerns require it.
3294 *
3295 * \param conf SSL configuration
3296 * \param hashes Ordered list of allowed signature hashes,
3297 * terminated by \c MBEDTLS_MD_NONE.
3298 */
3299 void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf,
3300 const int *hashes );
3301
3302 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
3303 /**
3304 * \brief Configure allowed signature algorithms for use in TLS 1.3
3305 *
3306 * \param conf The SSL configuration to use.
3307 * \param sig_algs List of allowed IANA values for TLS 1.3 signature algorithms,
3308 * terminated by \c MBEDTLS_TLS1_3_SIG_NONE. The list must remain
3309 * available throughout the lifetime of the conf object. Supported
3310 * values are available as \c MBEDTLS_TLS1_3_SIG_XXXX
3311 */
3312 void mbedtls_ssl_conf_sig_algs( mbedtls_ssl_config *conf,
3313 const uint16_t* sig_algs );
3314 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
3315 #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
3316
3317 #if defined(MBEDTLS_X509_CRT_PARSE_C)
3318 /**
3319 * \brief Set or reset the hostname to check against the received
3320 * server certificate. It sets the ServerName TLS extension,
3321 * too, if that extension is enabled. (client-side only)
3322 *
3323 * \param ssl SSL context
3324 * \param hostname the server hostname, may be NULL to clear hostname
3325
3326 * \note Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN.
3327 *
3328 * \return 0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on
3329 * allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on
3330 * too long input hostname.
3331 *
3332 * Hostname set to the one provided on success (cleared
3333 * when NULL). On allocation failure hostname is cleared.
3334 * On too long input failure, old hostname is unchanged.
3335 */
3336 int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname );
3337 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3338
3339 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
3340 /**
3341 * \brief Set own certificate and key for the current handshake
3342 *
3343 * \note Same as \c mbedtls_ssl_conf_own_cert() but for use within
3344 * the SNI callback.
3345 *
3346 * \param ssl SSL context
3347 * \param own_cert own public certificate chain
3348 * \param pk_key own private key
3349 *
3350 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
3351 */
3352 int mbedtls_ssl_set_hs_own_cert( mbedtls_ssl_context *ssl,
3353 mbedtls_x509_crt *own_cert,
3354 mbedtls_pk_context *pk_key );
3355
3356 /**
3357 * \brief Set the data required to verify peer certificate for the
3358 * current handshake
3359 *
3360 * \note Same as \c mbedtls_ssl_conf_ca_chain() but for use within
3361 * the SNI callback.
3362 *
3363 * \param ssl SSL context
3364 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
3365 * \param ca_crl trusted CA CRLs
3366 */
3367 void mbedtls_ssl_set_hs_ca_chain( mbedtls_ssl_context *ssl,
3368 mbedtls_x509_crt *ca_chain,
3369 mbedtls_x509_crl *ca_crl );
3370
3371 /**
3372 * \brief Set authmode for the current handshake.
3373 *
3374 * \note Same as \c mbedtls_ssl_conf_authmode() but for use within
3375 * the SNI callback.
3376 *
3377 * \param ssl SSL context
3378 * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or
3379 * MBEDTLS_SSL_VERIFY_REQUIRED
3380 */
3381 void mbedtls_ssl_set_hs_authmode( mbedtls_ssl_context *ssl,
3382 int authmode );
3383
3384 /**
3385 * \brief Set server side ServerName TLS extension callback
3386 * (optional, server-side only).
3387 *
3388 * If set, the ServerName callback is called whenever the
3389 * server receives a ServerName TLS extension from the client
3390 * during a handshake. The ServerName callback has the
3391 * following parameters: (void *parameter, mbedtls_ssl_context *ssl,
3392 * const unsigned char *hostname, size_t len). If a suitable
3393 * certificate is found, the callback must set the
3394 * certificate(s) and key(s) to use with \c
3395 * mbedtls_ssl_set_hs_own_cert() (can be called repeatedly),
3396 * and may optionally adjust the CA and associated CRL with \c
3397 * mbedtls_ssl_set_hs_ca_chain() as well as the client
3398 * authentication mode with \c mbedtls_ssl_set_hs_authmode(),
3399 * then must return 0. If no matching name is found, the
3400 * callback must either set a default cert, or
3401 * return non-zero to abort the handshake at this point.
3402 *
3403 * \param conf SSL configuration
3404 * \param f_sni verification function
3405 * \param p_sni verification parameter
3406 */
3407 void mbedtls_ssl_conf_sni( mbedtls_ssl_config *conf,
3408 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *,
3409 size_t),
3410 void *p_sni );
3411 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
3412
3413 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
3414 /**
3415 * \brief Set the EC J-PAKE password for current handshake.
3416 *
3417 * \note An internal copy is made, and destroyed as soon as the
3418 * handshake is completed, or when the SSL context is reset or
3419 * freed.
3420 *
3421 * \note The SSL context needs to be already set up. The right place
3422 * to call this function is between \c mbedtls_ssl_setup() or
3423 * \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake().
3424 *
3425 * \param ssl SSL context
3426 * \param pw EC J-PAKE password (pre-shared secret)
3427 * \param pw_len length of pw in bytes
3428 *
3429 * \return 0 on success, or a negative error code.
3430 */
3431 int mbedtls_ssl_set_hs_ecjpake_password( mbedtls_ssl_context *ssl,
3432 const unsigned char *pw,
3433 size_t pw_len );
3434 #endif /*MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
3435
3436 #if defined(MBEDTLS_SSL_ALPN)
3437 /**
3438 * \brief Set the supported Application Layer Protocols.
3439 *
3440 * \param conf SSL configuration
3441 * \param protos Pointer to a NULL-terminated list of supported protocols,
3442 * in decreasing preference order. The pointer to the list is
3443 * recorded by the library for later reference as required, so
3444 * the lifetime of the table must be atleast as long as the
3445 * lifetime of the SSL configuration structure.
3446 *
3447 * \return 0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA.
3448 */
3449 int mbedtls_ssl_conf_alpn_protocols( mbedtls_ssl_config *conf, const char **protos );
3450
3451 /**
3452 * \brief Get the name of the negotiated Application Layer Protocol.
3453 * This function should be called after the handshake is
3454 * completed.
3455 *
3456 * \param ssl SSL context
3457 *
3458 * \return Protcol name, or NULL if no protocol was negotiated.
3459 */
3460 const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl );
3461 #endif /* MBEDTLS_SSL_ALPN */
3462
3463 #if defined(MBEDTLS_SSL_DTLS_SRTP)
3464 #if defined(MBEDTLS_DEBUG_C)
mbedtls_ssl_get_srtp_profile_as_string(mbedtls_ssl_srtp_profile profile)3465 static inline const char *mbedtls_ssl_get_srtp_profile_as_string( mbedtls_ssl_srtp_profile profile )
3466 {
3467 switch( profile )
3468 {
3469 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80:
3470 return( "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80" );
3471 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32:
3472 return( "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" );
3473 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80:
3474 return( "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80" );
3475 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32:
3476 return( "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32" );
3477 default: break;
3478 }
3479 return( "" );
3480 }
3481 #endif /* MBEDTLS_DEBUG_C */
3482 /**
3483 * \brief Manage support for mki(master key id) value
3484 * in use_srtp extension.
3485 * MKI is an optional part of SRTP used for key management
3486 * and re-keying. See RFC3711 section 3.1 for details.
3487 * The default value is
3488 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED.
3489 *
3490 * \param conf The SSL configuration to manage mki support.
3491 * \param support_mki_value Enable or disable mki usage. Values are
3492 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED
3493 * or #MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED.
3494 */
3495 void mbedtls_ssl_conf_srtp_mki_value_supported( mbedtls_ssl_config *conf,
3496 int support_mki_value );
3497
3498 /**
3499 * \brief Set the supported DTLS-SRTP protection profiles.
3500 *
3501 * \param conf SSL configuration
3502 * \param profiles Pointer to a List of MBEDTLS_TLS_SRTP_UNSET terminated
3503 * supported protection profiles
3504 * in decreasing preference order.
3505 * The pointer to the list is recorded by the library
3506 * for later reference as required, so the lifetime
3507 * of the table must be at least as long as the lifetime
3508 * of the SSL configuration structure.
3509 * The list must not hold more than
3510 * MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH elements
3511 * (excluding the terminating MBEDTLS_TLS_SRTP_UNSET).
3512 *
3513 * \return 0 on success
3514 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA when the list of
3515 * protection profiles is incorrect.
3516 */
3517 int mbedtls_ssl_conf_dtls_srtp_protection_profiles
3518 ( mbedtls_ssl_config *conf,
3519 const mbedtls_ssl_srtp_profile *profiles );
3520
3521 /**
3522 * \brief Set the mki_value for the current DTLS-SRTP session.
3523 *
3524 * \param ssl SSL context to use.
3525 * \param mki_value The MKI value to set.
3526 * \param mki_len The length of the MKI value.
3527 *
3528 * \note This function is relevant on client side only.
3529 * The server discovers the mki value during handshake.
3530 * A mki value set on server side using this function
3531 * is ignored.
3532 *
3533 * \return 0 on success
3534 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA
3535 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE
3536 */
3537 int mbedtls_ssl_dtls_srtp_set_mki_value( mbedtls_ssl_context *ssl,
3538 unsigned char *mki_value,
3539 uint16_t mki_len );
3540 /**
3541 * \brief Get the negotiated DTLS-SRTP informations:
3542 * Protection profile and MKI value.
3543 *
3544 * \warning This function must be called after the handshake is
3545 * completed. The value returned by this function must
3546 * not be trusted or acted upon before the handshake completes.
3547 *
3548 * \param ssl The SSL context to query.
3549 * \param dtls_srtp_info The negotiated DTLS-SRTP informations:
3550 * - Protection profile in use.
3551 * A direct mapping of the iana defined value for protection
3552 * profile on an uint16_t.
3553 http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
3554 * #MBEDTLS_TLS_SRTP_UNSET if the use of SRTP was not negotiated
3555 * or peer's Hello packet was not parsed yet.
3556 * - mki size and value( if size is > 0 ).
3557 */
3558 void mbedtls_ssl_get_dtls_srtp_negotiation_result( const mbedtls_ssl_context *ssl,
3559 mbedtls_dtls_srtp_info *dtls_srtp_info );
3560 #endif /* MBEDTLS_SSL_DTLS_SRTP */
3561
3562 /**
3563 * \brief Set the maximum supported version sent from the client side
3564 * and/or accepted at the server side
3565 * (Default: MBEDTLS_SSL_MAX_MAJOR_VERSION, MBEDTLS_SSL_MAX_MINOR_VERSION)
3566 *
3567 * \note This ignores ciphersuites from higher versions.
3568 *
3569 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
3570 *
3571 * \param conf SSL configuration
3572 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
3573 * \param minor Minor version number (only MBEDTLS_SSL_MINOR_VERSION_3 supported)
3574 */
3575 void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor );
3576
3577 /**
3578 * \brief Set the minimum accepted SSL/TLS protocol version
3579 * (Default: TLS 1.2)
3580 *
3581 * \note Input outside of the SSL_MAX_XXXXX_VERSION and
3582 * SSL_MIN_XXXXX_VERSION range is ignored.
3583 *
3584 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
3585 *
3586 * \param conf SSL configuration
3587 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
3588 * \param minor Minor version number (only MBEDTLS_SSL_MINOR_VERSION_3 supported)
3589 */
3590 void mbedtls_ssl_conf_min_version( mbedtls_ssl_config *conf, int major, int minor );
3591
3592 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
3593 /**
3594 * \brief Enable or disable Encrypt-then-MAC
3595 * (Default: MBEDTLS_SSL_ETM_ENABLED)
3596 *
3597 * \note This should always be enabled, it is a security
3598 * improvement, and should not cause any interoperability
3599 * issue (used only if the peer supports it too).
3600 *
3601 * \param conf SSL configuration
3602 * \param etm MBEDTLS_SSL_ETM_ENABLED or MBEDTLS_SSL_ETM_DISABLED
3603 */
3604 void mbedtls_ssl_conf_encrypt_then_mac( mbedtls_ssl_config *conf, char etm );
3605 #endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
3606
3607 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
3608 /**
3609 * \brief Enable or disable Extended Master Secret negotiation.
3610 * (Default: MBEDTLS_SSL_EXTENDED_MS_ENABLED)
3611 *
3612 * \note This should always be enabled, it is a security fix to the
3613 * protocol, and should not cause any interoperability issue
3614 * (used only if the peer supports it too).
3615 *
3616 * \param conf SSL configuration
3617 * \param ems MBEDTLS_SSL_EXTENDED_MS_ENABLED or MBEDTLS_SSL_EXTENDED_MS_DISABLED
3618 */
3619 void mbedtls_ssl_conf_extended_master_secret( mbedtls_ssl_config *conf, char ems );
3620 #endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
3621
3622 #if defined(MBEDTLS_SSL_SRV_C)
3623 /**
3624 * \brief Whether to send a list of acceptable CAs in
3625 * CertificateRequest messages.
3626 * (Default: do send)
3627 *
3628 * \param conf SSL configuration
3629 * \param cert_req_ca_list MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or
3630 * MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED
3631 */
3632 void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf,
3633 char cert_req_ca_list );
3634 #endif /* MBEDTLS_SSL_SRV_C */
3635
3636 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
3637 /**
3638 * \brief Set the maximum fragment length to emit and/or negotiate.
3639 * (Typical: the smaller of #MBEDTLS_SSL_IN_CONTENT_LEN and
3640 * #MBEDTLS_SSL_OUT_CONTENT_LEN, usually `2^14` bytes)
3641 * (Server: set maximum fragment length to emit,
3642 * usually negotiated by the client during handshake)
3643 * (Client: set maximum fragment length to emit *and*
3644 * negotiate with the server during handshake)
3645 * (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE)
3646 *
3647 * \note On the client side, the maximum fragment length extension
3648 * *will not* be used, unless the maximum fragment length has
3649 * been set via this function to a value different than
3650 * #MBEDTLS_SSL_MAX_FRAG_LEN_NONE.
3651 *
3652 * \note With TLS, this currently only affects ApplicationData (sent
3653 * with \c mbedtls_ssl_read()), not handshake messages.
3654 * With DTLS, this affects both ApplicationData and handshake.
3655 *
3656 * \note This sets the maximum length for a record's payload,
3657 * excluding record overhead that will be added to it, see
3658 * \c mbedtls_ssl_get_record_expansion().
3659 *
3660 * \note For DTLS, it is also possible to set a limit for the total
3661 * size of daragrams passed to the transport layer, including
3662 * record overhead, see \c mbedtls_ssl_set_mtu().
3663 *
3664 * \param conf SSL configuration
3665 * \param mfl_code Code for maximum fragment length (allowed values:
3666 * MBEDTLS_SSL_MAX_FRAG_LEN_512, MBEDTLS_SSL_MAX_FRAG_LEN_1024,
3667 * MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096)
3668 *
3669 * \return 0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA
3670 */
3671 int mbedtls_ssl_conf_max_frag_len( mbedtls_ssl_config *conf, unsigned char mfl_code );
3672 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
3673
3674 #if defined(MBEDTLS_SSL_SRV_C)
3675 /**
3676 * \brief Pick the ciphersuites order according to the second parameter
3677 * in the SSL Server module (MBEDTLS_SSL_SRV_C).
3678 * (Default, if never called: MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER)
3679 *
3680 * \param conf SSL configuration
3681 * \param order Server or client (MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER
3682 * or MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_CLIENT)
3683 */
3684 void mbedtls_ssl_conf_preference_order( mbedtls_ssl_config *conf, int order );
3685 #endif /* MBEDTLS_SSL_SRV_C */
3686
3687 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
3688 /**
3689 * \brief Enable / Disable session tickets (client only).
3690 * (Default: MBEDTLS_SSL_SESSION_TICKETS_ENABLED.)
3691 *
3692 * \note On server, use \c mbedtls_ssl_conf_session_tickets_cb().
3693 *
3694 * \param conf SSL configuration
3695 * \param use_tickets Enable or disable (MBEDTLS_SSL_SESSION_TICKETS_ENABLED or
3696 * MBEDTLS_SSL_SESSION_TICKETS_DISABLED)
3697 */
3698 void mbedtls_ssl_conf_session_tickets( mbedtls_ssl_config *conf, int use_tickets );
3699 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
3700
3701 #if defined(MBEDTLS_SSL_RENEGOTIATION)
3702 /**
3703 * \brief Enable / Disable renegotiation support for connection when
3704 * initiated by peer
3705 * (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED)
3706 *
3707 * \warning It is recommended to always disable renegotation unless you
3708 * know you need it and you know what you're doing. In the
3709 * past, there have been several issues associated with
3710 * renegotiation or a poor understanding of its properties.
3711 *
3712 * \note Server-side, enabling renegotiation also makes the server
3713 * susceptible to a resource DoS by a malicious client.
3714 *
3715 * \param conf SSL configuration
3716 * \param renegotiation Enable or disable (MBEDTLS_SSL_RENEGOTIATION_ENABLED or
3717 * MBEDTLS_SSL_RENEGOTIATION_DISABLED)
3718 */
3719 void mbedtls_ssl_conf_renegotiation( mbedtls_ssl_config *conf, int renegotiation );
3720 #endif /* MBEDTLS_SSL_RENEGOTIATION */
3721
3722 /**
3723 * \brief Prevent or allow legacy renegotiation.
3724 * (Default: MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION)
3725 *
3726 * MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION allows connections to
3727 * be established even if the peer does not support
3728 * secure renegotiation, but does not allow renegotiation
3729 * to take place if not secure.
3730 * (Interoperable and secure option)
3731 *
3732 * MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION allows renegotiations
3733 * with non-upgraded peers. Allowing legacy renegotiation
3734 * makes the connection vulnerable to specific man in the
3735 * middle attacks. (See RFC 5746)
3736 * (Most interoperable and least secure option)
3737 *
3738 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE breaks off connections
3739 * if peer does not support secure renegotiation. Results
3740 * in interoperability issues with non-upgraded peers
3741 * that do not support renegotiation altogether.
3742 * (Most secure option, interoperability issues)
3743 *
3744 * \param conf SSL configuration
3745 * \param allow_legacy Prevent or allow (SSL_NO_LEGACY_RENEGOTIATION,
3746 * SSL_ALLOW_LEGACY_RENEGOTIATION or
3747 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE)
3748 */
3749 void mbedtls_ssl_conf_legacy_renegotiation( mbedtls_ssl_config *conf, int allow_legacy );
3750
3751 #if defined(MBEDTLS_SSL_RENEGOTIATION)
3752 /**
3753 * \brief Enforce renegotiation requests.
3754 * (Default: enforced, max_records = 16)
3755 *
3756 * When we request a renegotiation, the peer can comply or
3757 * ignore the request. This function allows us to decide
3758 * whether to enforce our renegotiation requests by closing
3759 * the connection if the peer doesn't comply.
3760 *
3761 * However, records could already be in transit from the peer
3762 * when the request is emitted. In order to increase
3763 * reliability, we can accept a number of records before the
3764 * expected handshake records.
3765 *
3766 * The optimal value is highly dependent on the specific usage
3767 * scenario.
3768 *
3769 * \note With DTLS and server-initiated renegotiation, the
3770 * HelloRequest is retransmited every time mbedtls_ssl_read() times
3771 * out or receives Application Data, until:
3772 * - max_records records have beens seen, if it is >= 0, or
3773 * - the number of retransmits that would happen during an
3774 * actual handshake has been reached.
3775 * Please remember the request might be lost a few times
3776 * if you consider setting max_records to a really low value.
3777 *
3778 * \warning On client, the grace period can only happen during
3779 * mbedtls_ssl_read(), as opposed to mbedtls_ssl_write() and mbedtls_ssl_renegotiate()
3780 * which always behave as if max_record was 0. The reason is,
3781 * if we receive application data from the server, we need a
3782 * place to write it, which only happens during mbedtls_ssl_read().
3783 *
3784 * \param conf SSL configuration
3785 * \param max_records Use MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to
3786 * enforce renegotiation, or a non-negative value to enforce
3787 * it but allow for a grace period of max_records records.
3788 */
3789 void mbedtls_ssl_conf_renegotiation_enforced( mbedtls_ssl_config *conf, int max_records );
3790
3791 /**
3792 * \brief Set record counter threshold for periodic renegotiation.
3793 * (Default: 2^48 - 1)
3794 *
3795 * Renegotiation is automatically triggered when a record
3796 * counter (outgoing or incoming) crosses the defined
3797 * threshold. The default value is meant to prevent the
3798 * connection from being closed when the counter is about to
3799 * reached its maximal value (it is not allowed to wrap).
3800 *
3801 * Lower values can be used to enforce policies such as "keys
3802 * must be refreshed every N packets with cipher X".
3803 *
3804 * The renegotiation period can be disabled by setting
3805 * conf->disable_renegotiation to
3806 * MBEDTLS_SSL_RENEGOTIATION_DISABLED.
3807 *
3808 * \note When the configured transport is
3809 * MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation
3810 * period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM,
3811 * the maximum renegotiation period is 2^64 - 1.
3812 *
3813 * \param conf SSL configuration
3814 * \param period The threshold value: a big-endian 64-bit number.
3815 */
3816 void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf,
3817 const unsigned char period[8] );
3818 #endif /* MBEDTLS_SSL_RENEGOTIATION */
3819
3820 /**
3821 * \brief Check if there is data already read from the
3822 * underlying transport but not yet processed.
3823 *
3824 * \param ssl SSL context
3825 *
3826 * \return 0 if nothing's pending, 1 otherwise.
3827 *
3828 * \note This is different in purpose and behaviour from
3829 * \c mbedtls_ssl_get_bytes_avail in that it considers
3830 * any kind of unprocessed data, not only unread
3831 * application data. If \c mbedtls_ssl_get_bytes
3832 * returns a non-zero value, this function will
3833 * also signal pending data, but the converse does
3834 * not hold. For example, in DTLS there might be
3835 * further records waiting to be processed from
3836 * the current underlying transport's datagram.
3837 *
3838 * \note If this function returns 1 (data pending), this
3839 * does not imply that a subsequent call to
3840 * \c mbedtls_ssl_read will provide any data;
3841 * e.g., the unprocessed data might turn out
3842 * to be an alert or a handshake message.
3843 *
3844 * \note This function is useful in the following situation:
3845 * If the SSL/TLS module successfully returns from an
3846 * operation - e.g. a handshake or an application record
3847 * read - and you're awaiting incoming data next, you
3848 * must not immediately idle on the underlying transport
3849 * to have data ready, but you need to check the value
3850 * of this function first. The reason is that the desired
3851 * data might already be read but not yet processed.
3852 * If, in contrast, a previous call to the SSL/TLS module
3853 * returned MBEDTLS_ERR_SSL_WANT_READ, it is not necessary
3854 * to call this function, as the latter error code entails
3855 * that all internal data has been processed.
3856 *
3857 */
3858 int mbedtls_ssl_check_pending( const mbedtls_ssl_context *ssl );
3859
3860 /**
3861 * \brief Return the number of application data bytes
3862 * remaining to be read from the current record.
3863 *
3864 * \param ssl SSL context
3865 *
3866 * \return How many bytes are available in the application
3867 * data record read buffer.
3868 *
3869 * \note When working over a datagram transport, this is
3870 * useful to detect the current datagram's boundary
3871 * in case \c mbedtls_ssl_read has written the maximal
3872 * amount of data fitting into the input buffer.
3873 *
3874 */
3875 size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl );
3876
3877 /**
3878 * \brief Return the result of the certificate verification
3879 *
3880 * \param ssl The SSL context to use.
3881 *
3882 * \return \c 0 if the certificate verification was successful.
3883 * \return \c -1u if the result is not available. This may happen
3884 * e.g. if the handshake aborts early, or a verification
3885 * callback returned a fatal error.
3886 * \return A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX
3887 * and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h.
3888 */
3889 uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl );
3890
3891 /**
3892 * \brief Return the name of the current ciphersuite
3893 *
3894 * \param ssl SSL context
3895 *
3896 * \return a string containing the ciphersuite name
3897 */
3898 const char *mbedtls_ssl_get_ciphersuite( const mbedtls_ssl_context *ssl );
3899
3900 /**
3901 * \brief Return the current TLS version
3902 *
3903 * \param ssl SSL context
3904 *
3905 * \return a string containing the TLS version
3906 */
3907 const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl );
3908
3909 /**
3910 * \brief Return the (maximum) number of bytes added by the record
3911 * layer: header + encryption/MAC overhead (inc. padding)
3912 *
3913 * \param ssl SSL context
3914 *
3915 * \return Current maximum record expansion in bytes
3916 */
3917 int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl );
3918
3919 /**
3920 * \brief Return the current maximum outgoing record payload in bytes.
3921 *
3922 * \note The logic to determine the maximum outgoing record payload is
3923 * version-specific. It takes into account various factors, such as
3924 * the mbedtls_config.h setting \c MBEDTLS_SSL_OUT_CONTENT_LEN, extensions
3925 * such as the max fragment length or record size limit extension if
3926 * used, and for DTLS the path MTU as configured and current
3927 * record expansion.
3928 *
3929 * \note With DTLS, \c mbedtls_ssl_write() will return an error if
3930 * called with a larger length value.
3931 * With TLS, \c mbedtls_ssl_write() will fragment the input if
3932 * necessary and return the number of bytes written; it is up
3933 * to the caller to call \c mbedtls_ssl_write() again in
3934 * order to send the remaining bytes if any.
3935 *
3936 * \sa mbedtls_ssl_get_max_out_record_payload()
3937 * \sa mbedtls_ssl_get_record_expansion()
3938 *
3939 * \param ssl SSL context
3940 *
3941 * \return Current maximum payload for an outgoing record,
3942 * or a negative error code.
3943 */
3944 int mbedtls_ssl_get_max_out_record_payload( const mbedtls_ssl_context *ssl );
3945
3946 /**
3947 * \brief Return the current maximum incoming record payload in bytes.
3948 *
3949 * \note The logic to determine the maximum outgoing record payload is
3950 * version-specific. It takes into account various factors, such as
3951 * the mbedtls_config.h setting \c MBEDTLS_SSL_IN_CONTENT_LEN, extensions
3952 * such as the max fragment length extension or record size limit
3953 * extension if used, and the current record expansion.
3954 *
3955 * \sa mbedtls_ssl_set_mtu()
3956 * \sa mbedtls_ssl_get_max_in_record_payload()
3957 * \sa mbedtls_ssl_get_record_expansion()
3958 *
3959 * \param ssl SSL context
3960 *
3961 * \return Current maximum payload for an outgoing record,
3962 * or a negative error code.
3963 */
3964 int mbedtls_ssl_get_max_in_record_payload( const mbedtls_ssl_context *ssl );
3965
3966 #if defined(MBEDTLS_X509_CRT_PARSE_C)
3967 /**
3968 * \brief Return the peer certificate from the current connection.
3969 *
3970 * \param ssl The SSL context to use. This must be initialized and setup.
3971 *
3972 * \return The current peer certificate, if available.
3973 * The returned certificate is owned by the SSL context and
3974 * is valid only until the next call to the SSL API.
3975 * \return \c NULL if no peer certificate is available. This might
3976 * be because the chosen ciphersuite doesn't use CRTs
3977 * (PSK-based ciphersuites, for example), or because
3978 * #MBEDTLS_SSL_KEEP_PEER_CERTIFICATE has been disabled,
3979 * allowing the stack to free the peer's CRT to save memory.
3980 *
3981 * \note For one-time inspection of the peer's certificate during
3982 * the handshake, consider registering an X.509 CRT verification
3983 * callback through mbedtls_ssl_conf_verify() instead of calling
3984 * this function. Using mbedtls_ssl_conf_verify() also comes at
3985 * the benefit of allowing you to influence the verification
3986 * process, for example by masking expected and tolerated
3987 * verification failures.
3988 *
3989 * \warning You must not use the pointer returned by this function
3990 * after any further call to the SSL API, including
3991 * mbedtls_ssl_read() and mbedtls_ssl_write(); this is
3992 * because the pointer might change during renegotiation,
3993 * which happens transparently to the user.
3994 * If you want to use the certificate across API calls,
3995 * you must make a copy.
3996 */
3997 const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert( const mbedtls_ssl_context *ssl );
3998 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3999
4000 #if defined(MBEDTLS_SSL_CLI_C)
4001 /**
4002 * \brief Export a session in order to resume it later.
4003 *
4004 * \param ssl The SSL context representing the connection for which to
4005 * to export a session structure for later resumption.
4006 * \param session The target structure in which to store the exported session.
4007 * This must have been initialized with mbedtls_ssl_init_session()
4008 * but otherwise be unused.
4009 *
4010 * \note This function can handle a variety of mechanisms for session
4011 * resumption: For TLS 1.2, both session ID-based resumption and
4012 * ticket-based resumption will be considered. For TLS 1.3,
4013 * once implemented, sessions equate to tickets, and calling
4014 * this function multiple times will export the available
4015 * tickets one a time until no further tickets are available,
4016 * in which case MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE will
4017 * be returned.
4018 *
4019 * \note Calling this function multiple times will only be useful
4020 * once TLS 1.3 is supported. For TLS 1.2 connections, this
4021 * function should be called at most once.
4022 *
4023 * \return \c 0 if successful. In this case, \p session can be used for
4024 * session resumption by passing it to mbedtls_ssl_set_session(),
4025 * and serialized for storage via mbedtls_ssl_session_save().
4026 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no further session
4027 * is available for export.
4028 * This error is a non-fatal, and has no observable effect on
4029 * the SSL context or the destination session.
4030 * \return Another negative error code on other kinds of failure.
4031 *
4032 * \sa mbedtls_ssl_set_session()
4033 * \sa mbedtls_ssl_session_save()
4034 */
4035 int mbedtls_ssl_get_session( const mbedtls_ssl_context *ssl,
4036 mbedtls_ssl_session *session );
4037 #endif /* MBEDTLS_SSL_CLI_C */
4038
4039 /**
4040 * \brief Perform the SSL handshake
4041 *
4042 * \param ssl SSL context
4043 *
4044 * \return \c 0 if successful.
4045 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4046 * if the handshake is incomplete and waiting for data to
4047 * be available for reading from or writing to the underlying
4048 * transport - in this case you must call this function again
4049 * when the underlying transport is ready for the operation.
4050 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4051 * operation is in progress (see
4052 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4053 * must call this function again when the operation is ready.
4054 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4055 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4056 * in this case you must call this function again to complete
4057 * the handshake when you're done attending other tasks.
4058 * \return #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED if DTLS is in use
4059 * and the client did not demonstrate reachability yet - in
4060 * this case you must stop using the context (see below).
4061 * \return Another SSL error code - in this case you must stop using
4062 * the context (see below).
4063 *
4064 * \warning If this function returns something other than
4065 * \c 0,
4066 * #MBEDTLS_ERR_SSL_WANT_READ,
4067 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4068 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4069 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
4070 * you must stop using the SSL context for reading or writing,
4071 * and either free it or call \c mbedtls_ssl_session_reset()
4072 * on it before re-using it for a new connection; the current
4073 * connection must be closed.
4074 *
4075 * \note If DTLS is in use, then you may choose to handle
4076 * #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging
4077 * purposes, as it is an expected return value rather than an
4078 * actual error, but you still need to reset/free the context.
4079 *
4080 * \note Remarks regarding event-driven DTLS:
4081 * If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
4082 * from the underlying transport layer is currently being processed,
4083 * and it is safe to idle until the timer or the underlying transport
4084 * signal a new event. This is not true for a successful handshake,
4085 * in which case the datagram of the underlying transport that is
4086 * currently being processed might or might not contain further
4087 * DTLS records.
4088 */
4089 int mbedtls_ssl_handshake( mbedtls_ssl_context *ssl );
4090
4091 /**
4092 * \brief Perform a single step of the SSL handshake
4093 *
4094 * \note The state of the context (ssl->state) will be at
4095 * the next state after this function returns \c 0. Do not
4096 * call this function if state is MBEDTLS_SSL_HANDSHAKE_OVER.
4097 *
4098 * \param ssl SSL context
4099 *
4100 * \return See mbedtls_ssl_handshake().
4101 *
4102 * \warning If this function returns something other than \c 0,
4103 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
4104 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4105 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
4106 * the SSL context for reading or writing, and either free it
4107 * or call \c mbedtls_ssl_session_reset() on it before
4108 * re-using it for a new connection; the current connection
4109 * must be closed.
4110 */
4111 int mbedtls_ssl_handshake_step( mbedtls_ssl_context *ssl );
4112
4113 #if defined(MBEDTLS_SSL_RENEGOTIATION)
4114 /**
4115 * \brief Initiate an SSL renegotiation on the running connection.
4116 * Client: perform the renegotiation right now.
4117 * Server: request renegotiation, which will be performed
4118 * during the next call to mbedtls_ssl_read() if honored by
4119 * client.
4120 *
4121 * \param ssl SSL context
4122 *
4123 * \return 0 if successful, or any mbedtls_ssl_handshake() return
4124 * value except #MBEDTLS_ERR_SSL_CLIENT_RECONNECT that can't
4125 * happen during a renegotiation.
4126 *
4127 * \warning If this function returns something other than \c 0,
4128 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
4129 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4130 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
4131 * the SSL context for reading or writing, and either free it
4132 * or call \c mbedtls_ssl_session_reset() on it before
4133 * re-using it for a new connection; the current connection
4134 * must be closed.
4135 *
4136 */
4137 int mbedtls_ssl_renegotiate( mbedtls_ssl_context *ssl );
4138 #endif /* MBEDTLS_SSL_RENEGOTIATION */
4139
4140 /**
4141 * \brief Read at most 'len' application data bytes
4142 *
4143 * \param ssl SSL context
4144 * \param buf buffer that will hold the data
4145 * \param len maximum number of bytes to read
4146 *
4147 * \return The (positive) number of bytes read if successful.
4148 * \return \c 0 if the read end of the underlying transport was closed
4149 * without sending a CloseNotify beforehand, which might happen
4150 * because of various reasons (internal error of an underlying
4151 * stack, non-conformant peer not sending a CloseNotify and
4152 * such) - in this case you must stop using the context
4153 * (see below).
4154 * \return #MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY if the underlying
4155 * transport is still functional, but the peer has
4156 * acknowledged to not send anything anymore.
4157 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4158 * if the handshake is incomplete and waiting for data to
4159 * be available for reading from or writing to the underlying
4160 * transport - in this case you must call this function again
4161 * when the underlying transport is ready for the operation.
4162 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4163 * operation is in progress (see
4164 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4165 * must call this function again when the operation is ready.
4166 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4167 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4168 * in this case you must call this function again to complete
4169 * the handshake when you're done attending other tasks.
4170 * \return #MBEDTLS_ERR_SSL_CLIENT_RECONNECT if we're at the server
4171 * side of a DTLS connection and the client is initiating a
4172 * new connection using the same source port. See below.
4173 * \return Another SSL error code - in this case you must stop using
4174 * the context (see below).
4175 *
4176 * \warning If this function returns something other than
4177 * a positive value,
4178 * #MBEDTLS_ERR_SSL_WANT_READ,
4179 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4180 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
4181 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
4182 * #MBEDTLS_ERR_SSL_CLIENT_RECONNECT,
4183 * you must stop using the SSL context for reading or writing,
4184 * and either free it or call \c mbedtls_ssl_session_reset()
4185 * on it before re-using it for a new connection; the current
4186 * connection must be closed.
4187 *
4188 * \note When this function returns #MBEDTLS_ERR_SSL_CLIENT_RECONNECT
4189 * (which can only happen server-side), it means that a client
4190 * is initiating a new connection using the same source port.
4191 * You can either treat that as a connection close and wait
4192 * for the client to resend a ClientHello, or directly
4193 * continue with \c mbedtls_ssl_handshake() with the same
4194 * context (as it has been reset internally). Either way, you
4195 * must make sure this is seen by the application as a new
4196 * connection: application state, if any, should be reset, and
4197 * most importantly the identity of the client must be checked
4198 * again. WARNING: not validating the identity of the client
4199 * again, or not transmitting the new identity to the
4200 * application layer, would allow authentication bypass!
4201 *
4202 * \note Remarks regarding event-driven DTLS:
4203 * - If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
4204 * from the underlying transport layer is currently being processed,
4205 * and it is safe to idle until the timer or the underlying transport
4206 * signal a new event.
4207 * - This function may return MBEDTLS_ERR_SSL_WANT_READ even if data was
4208 * initially available on the underlying transport, as this data may have
4209 * been only e.g. duplicated messages or a renegotiation request.
4210 * Therefore, you must be prepared to receive MBEDTLS_ERR_SSL_WANT_READ even
4211 * when reacting to an incoming-data event from the underlying transport.
4212 * - On success, the datagram of the underlying transport that is currently
4213 * being processed may contain further DTLS records. You should call
4214 * \c mbedtls_ssl_check_pending to check for remaining records.
4215 *
4216 */
4217 int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len );
4218
4219 /**
4220 * \brief Try to write exactly 'len' application data bytes
4221 *
4222 * \warning This function will do partial writes in some cases. If the
4223 * return value is non-negative but less than length, the
4224 * function must be called again with updated arguments:
4225 * buf + ret, len - ret (if ret is the return value) until
4226 * it returns a value equal to the last 'len' argument.
4227 *
4228 * \param ssl SSL context
4229 * \param buf buffer holding the data
4230 * \param len how many bytes must be written
4231 *
4232 * \return The (non-negative) number of bytes actually written if
4233 * successful (may be less than \p len).
4234 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4235 * if the handshake is incomplete and waiting for data to
4236 * be available for reading from or writing to the underlying
4237 * transport - in this case you must call this function again
4238 * when the underlying transport is ready for the operation.
4239 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4240 * operation is in progress (see
4241 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4242 * must call this function again when the operation is ready.
4243 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4244 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4245 * in this case you must call this function again to complete
4246 * the handshake when you're done attending other tasks.
4247 * \return Another SSL error code - in this case you must stop using
4248 * the context (see below).
4249 *
4250 * \warning If this function returns something other than
4251 * a non-negative value,
4252 * #MBEDTLS_ERR_SSL_WANT_READ,
4253 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4254 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4255 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
4256 * you must stop using the SSL context for reading or writing,
4257 * and either free it or call \c mbedtls_ssl_session_reset()
4258 * on it before re-using it for a new connection; the current
4259 * connection must be closed.
4260 *
4261 * \note When this function returns #MBEDTLS_ERR_SSL_WANT_WRITE/READ,
4262 * it must be called later with the *same* arguments,
4263 * until it returns a value greater that or equal to 0. When
4264 * the function returns #MBEDTLS_ERR_SSL_WANT_WRITE there may be
4265 * some partial data in the output buffer, however this is not
4266 * yet sent.
4267 *
4268 * \note If the requested length is greater than the maximum
4269 * fragment length (either the built-in limit or the one set
4270 * or negotiated with the peer), then:
4271 * - with TLS, less bytes than requested are written.
4272 * - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned.
4273 * \c mbedtls_ssl_get_max_out_record_payload() may be used to
4274 * query the active maximum fragment length.
4275 *
4276 * \note Attempting to write 0 bytes will result in an empty TLS
4277 * application record being sent.
4278 */
4279 int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len );
4280
4281 /**
4282 * \brief Send an alert message
4283 *
4284 * \param ssl SSL context
4285 * \param level The alert level of the message
4286 * (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL)
4287 * \param message The alert message (SSL_ALERT_MSG_*)
4288 *
4289 * \return 0 if successful, or a specific SSL error code.
4290 *
4291 * \note If this function returns something other than 0 or
4292 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
4293 * the SSL context for reading or writing, and either free it or
4294 * call \c mbedtls_ssl_session_reset() on it before re-using it
4295 * for a new connection; the current connection must be closed.
4296 */
4297 int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl,
4298 unsigned char level,
4299 unsigned char message );
4300 /**
4301 * \brief Notify the peer that the connection is being closed
4302 *
4303 * \param ssl SSL context
4304 *
4305 * \return 0 if successful, or a specific SSL error code.
4306 *
4307 * \note If this function returns something other than 0 or
4308 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
4309 * the SSL context for reading or writing, and either free it or
4310 * call \c mbedtls_ssl_session_reset() on it before re-using it
4311 * for a new connection; the current connection must be closed.
4312 */
4313 int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl );
4314
4315 /**
4316 * \brief Free referenced items in an SSL context and clear memory
4317 *
4318 * \param ssl SSL context
4319 */
4320 void mbedtls_ssl_free( mbedtls_ssl_context *ssl );
4321
4322 #if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION)
4323 /**
4324 * \brief Save an active connection as serialized data in a buffer.
4325 * This allows the freeing or re-using of the SSL context
4326 * while still picking up the connection later in a way that
4327 * it entirely transparent to the peer.
4328 *
4329 * \see mbedtls_ssl_context_load()
4330 *
4331 * \note This feature is currently only available under certain
4332 * conditions, see the documentation of the return value
4333 * #MBEDTLS_ERR_SSL_BAD_INPUT_DATA for details.
4334 *
4335 * \note When this function succeeds, it calls
4336 * mbedtls_ssl_session_reset() on \p ssl which as a result is
4337 * no longer associated with the connection that has been
4338 * serialized. This avoids creating copies of the connection
4339 * state. You're then free to either re-use the context
4340 * structure for a different connection, or call
4341 * mbedtls_ssl_free() on it. See the documentation of
4342 * mbedtls_ssl_session_reset() for more details.
4343 *
4344 * \param ssl The SSL context to save. On success, it is no longer
4345 * associated with the connection that has been serialized.
4346 * \param buf The buffer to write the serialized data to. It must be a
4347 * writeable buffer of at least \p buf_len bytes, or may be \c
4348 * NULL if \p buf_len is \c 0.
4349 * \param buf_len The number of bytes available for writing in \p buf.
4350 * \param olen The size in bytes of the data that has been or would have
4351 * been written. It must point to a valid \c size_t.
4352 *
4353 * \note \p olen is updated to the correct value regardless of
4354 * whether \p buf_len was large enough. This makes it possible
4355 * to determine the necessary size by calling this function
4356 * with \p buf set to \c NULL and \p buf_len to \c 0. However,
4357 * the value of \p olen is only guaranteed to be correct when
4358 * the function returns #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL or
4359 * \c 0. If the return value is different, then the value of
4360 * \p olen is undefined.
4361 *
4362 * \return \c 0 if successful.
4363 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
4364 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed
4365 * while reseting the context.
4366 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if a handshake is in
4367 * progress, or there is pending data for reading or sending,
4368 * or the connection does not use DTLS 1.2 with an AEAD
4369 * ciphersuite, or renegotiation is enabled.
4370 */
4371 int mbedtls_ssl_context_save( mbedtls_ssl_context *ssl,
4372 unsigned char *buf,
4373 size_t buf_len,
4374 size_t *olen );
4375
4376 /**
4377 * \brief Load serialized connection data to an SSL context.
4378 *
4379 * \see mbedtls_ssl_context_save()
4380 *
4381 * \warning The same serialized data must never be loaded into more
4382 * that one context. In order to ensure that, after
4383 * successfully loading serialized data to an SSL context, you
4384 * should immediately destroy or invalidate all copies of the
4385 * serialized data that was loaded. Loading the same data in
4386 * more than one context would cause severe security failures
4387 * including but not limited to loss of confidentiality.
4388 *
4389 * \note Before calling this function, the SSL context must be
4390 * prepared in one of the two following ways. The first way is
4391 * to take a context freshly initialised with
4392 * mbedtls_ssl_init() and call mbedtls_ssl_setup() on it with
4393 * the same ::mbedtls_ssl_config structure that was used in
4394 * the original connection. The second way is to
4395 * call mbedtls_ssl_session_reset() on a context that was
4396 * previously prepared as above but used in the meantime.
4397 * Either way, you must not use the context to perform a
4398 * handshake between calling mbedtls_ssl_setup() or
4399 * mbedtls_ssl_session_reset() and calling this function. You
4400 * may however call other setter functions in that time frame
4401 * as indicated in the note below.
4402 *
4403 * \note Before or after calling this function successfully, you
4404 * also need to configure some connection-specific callbacks
4405 * and settings before you can use the connection again
4406 * (unless they were already set before calling
4407 * mbedtls_ssl_session_reset() and the values are suitable for
4408 * the present connection). Specifically, you want to call
4409 * at least mbedtls_ssl_set_bio() and
4410 * mbedtls_ssl_set_timer_cb(). All other SSL setter functions
4411 * are not necessary to call, either because they're only used
4412 * in handshakes, or because the setting is already saved. You
4413 * might choose to call them anyway, for example in order to
4414 * share code between the cases of establishing a new
4415 * connection and the case of loading an already-established
4416 * connection.
4417 *
4418 * \note If you have new information about the path MTU, you want to
4419 * call mbedtls_ssl_set_mtu() after calling this function, as
4420 * otherwise this function would overwrite your
4421 * newly-configured value with the value that was active when
4422 * the context was saved.
4423 *
4424 * \note When this function returns an error code, it calls
4425 * mbedtls_ssl_free() on \p ssl. In this case, you need to
4426 * prepare the context with the usual sequence starting with a
4427 * call to mbedtls_ssl_init() if you want to use it again.
4428 *
4429 * \param ssl The SSL context structure to be populated. It must have
4430 * been prepared as described in the note above.
4431 * \param buf The buffer holding the serialized connection data. It must
4432 * be a readable buffer of at least \p len bytes.
4433 * \param len The size of the serialized data in bytes.
4434 *
4435 * \return \c 0 if successful.
4436 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
4437 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
4438 * comes from a different Mbed TLS version or build.
4439 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
4440 */
4441 int mbedtls_ssl_context_load( mbedtls_ssl_context *ssl,
4442 const unsigned char *buf,
4443 size_t len );
4444 #endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */
4445
4446 /**
4447 * \brief Initialize an SSL configuration context
4448 * Just makes the context ready for
4449 * mbedtls_ssl_config_defaults() or mbedtls_ssl_config_free().
4450 *
4451 * \note You need to call mbedtls_ssl_config_defaults() unless you
4452 * manually set all of the relevant fields yourself.
4453 *
4454 * \param conf SSL configuration context
4455 */
4456 void mbedtls_ssl_config_init( mbedtls_ssl_config *conf );
4457
4458 /**
4459 * \brief Load reasonnable default SSL configuration values.
4460 * (You need to call mbedtls_ssl_config_init() first.)
4461 *
4462 * \param conf SSL configuration context
4463 * \param endpoint MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
4464 * \param transport MBEDTLS_SSL_TRANSPORT_STREAM for TLS, or
4465 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS
4466 * \param preset a MBEDTLS_SSL_PRESET_XXX value
4467 *
4468 * \note See \c mbedtls_ssl_conf_transport() for notes on DTLS.
4469 *
4470 * \return 0 if successful, or
4471 * MBEDTLS_ERR_XXX_ALLOC_FAILED on memory allocation error.
4472 */
4473 int mbedtls_ssl_config_defaults( mbedtls_ssl_config *conf,
4474 int endpoint, int transport, int preset );
4475
4476 /**
4477 * \brief Free an SSL configuration context
4478 *
4479 * \param conf SSL configuration context
4480 */
4481 void mbedtls_ssl_config_free( mbedtls_ssl_config *conf );
4482
4483 /**
4484 * \brief Initialize SSL session structure
4485 *
4486 * \param session SSL session
4487 */
4488 void mbedtls_ssl_session_init( mbedtls_ssl_session *session );
4489
4490 /**
4491 * \brief Free referenced items in an SSL session including the
4492 * peer certificate and clear memory
4493 *
4494 * \note A session object can be freed even if the SSL context
4495 * that was used to retrieve the session is still in use.
4496 *
4497 * \param session SSL session
4498 */
4499 void mbedtls_ssl_session_free( mbedtls_ssl_session *session );
4500
4501 /**
4502 * \brief TLS-PRF function for key derivation.
4503 *
4504 * \param prf The tls_prf type function type to be used.
4505 * \param secret Secret for the key derivation function.
4506 * \param slen Length of the secret.
4507 * \param label String label for the key derivation function,
4508 * terminated with null character.
4509 * \param random Random bytes.
4510 * \param rlen Length of the random bytes buffer.
4511 * \param dstbuf The buffer holding the derived key.
4512 * \param dlen Length of the output buffer.
4513 *
4514 * \return 0 on success. An SSL specific error on failure.
4515 */
4516 int mbedtls_ssl_tls_prf( const mbedtls_tls_prf_types prf,
4517 const unsigned char *secret, size_t slen,
4518 const char *label,
4519 const unsigned char *random, size_t rlen,
4520 unsigned char *dstbuf, size_t dlen );
4521
4522 #ifdef __cplusplus
4523 }
4524 #endif
4525
4526 #endif /* ssl.h */
4527