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 OR GPL-2.0-or-later
9 */
10 #ifndef MBEDTLS_SSL_H
11 #define MBEDTLS_SSL_H
12 #include "mbedtls/platform_util.h"
13 #include "mbedtls/private_access.h"
14
15 #include "mbedtls/build_info.h"
16
17 #include "mbedtls/bignum.h"
18 #include "mbedtls/ecp.h"
19
20 #include "mbedtls/ssl_ciphersuites.h"
21
22 #if defined(MBEDTLS_X509_CRT_PARSE_C)
23 #include "mbedtls/x509_crt.h"
24 #include "mbedtls/x509_crl.h"
25 #endif
26
27 #if defined(MBEDTLS_DHM_C)
28 #include "mbedtls/dhm.h"
29 #endif
30
31 #include "mbedtls/md.h"
32
33 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_ANY_ENABLED)
34 #include "mbedtls/ecdh.h"
35 #endif
36
37 #if defined(MBEDTLS_HAVE_TIME)
38 #include "mbedtls/platform_time.h"
39 #endif
40
41 #include "psa/crypto.h"
42
43 /*
44 * SSL Error codes
45 */
46 /** A cryptographic operation is in progress. Try again later. */
47 #define MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS -0x7000
48 /** The requested feature is not available. */
49 #define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE -0x7080
50 /** Bad input parameters to function. */
51 #define MBEDTLS_ERR_SSL_BAD_INPUT_DATA -0x7100
52 /** Verification of the message MAC failed. */
53 #define MBEDTLS_ERR_SSL_INVALID_MAC -0x7180
54 /** An invalid SSL record was received. */
55 #define MBEDTLS_ERR_SSL_INVALID_RECORD -0x7200
56 /** The connection indicated an EOF. */
57 #define MBEDTLS_ERR_SSL_CONN_EOF -0x7280
58 /** A message could not be parsed due to a syntactic error. */
59 #define MBEDTLS_ERR_SSL_DECODE_ERROR -0x7300
60 /* Error space gap */
61 /** No RNG was provided to the SSL module. */
62 #define MBEDTLS_ERR_SSL_NO_RNG -0x7400
63 /** No client certification received from the client, but required by the authentication mode. */
64 #define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE -0x7480
65 /** Client received an extended server hello containing an unsupported extension */
66 #define MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION -0x7500
67 /** No ALPN protocols supported that the client advertises */
68 #define MBEDTLS_ERR_SSL_NO_APPLICATION_PROTOCOL -0x7580
69 /** The own private key or pre-shared key is not set, but needed. */
70 #define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED -0x7600
71 /** No CA Chain is set, but required to operate. */
72 #define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED -0x7680
73 /** An unexpected message was received from our peer. */
74 #define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE -0x7700
75 /** A fatal alert message was received from our peer. */
76 #define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE -0x7780
77 /** No server could be identified matching the client's SNI. */
78 #define MBEDTLS_ERR_SSL_UNRECOGNIZED_NAME -0x7800
79 /** The peer notified us that the connection is going to be closed. */
80 #define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY -0x7880
81 /* Error space gap */
82 /* Error space gap */
83 /** Processing of the Certificate handshake message failed. */
84 #define MBEDTLS_ERR_SSL_BAD_CERTIFICATE -0x7A00
85 /* Error space gap */
86 /** A TLS 1.3 NewSessionTicket message has been received. */
87 #define MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET -0x7B00
88 /** Not possible to read early data */
89 #define MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA -0x7B80
90 /**
91 * Early data has been received as part of an on-going handshake.
92 * This error code can be returned only on server side if and only if early
93 * data has been enabled by means of the mbedtls_ssl_conf_early_data() API.
94 * This error code can then be returned by mbedtls_ssl_handshake(),
95 * mbedtls_ssl_handshake_step(), mbedtls_ssl_read() or mbedtls_ssl_write() if
96 * early data has been received as part of the handshake sequence they
97 * triggered. To read the early data, call mbedtls_ssl_read_early_data().
98 */
99 #define MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA -0x7C00
100 /** Not possible to write early data */
101 #define MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA -0x7C80
102 /* Error space gap */
103 /* Error space gap */
104 /* Error space gap */
105 /* Error space gap */
106 /** Cache entry not found */
107 #define MBEDTLS_ERR_SSL_CACHE_ENTRY_NOT_FOUND -0x7E80
108 /** Memory allocation failed */
109 #define MBEDTLS_ERR_SSL_ALLOC_FAILED -0x7F00
110 /** Hardware acceleration function returned with error */
111 #define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED -0x7F80
112 /** Hardware acceleration function skipped / left alone data */
113 #define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH -0x6F80
114 /** Handshake protocol not within min/max boundaries */
115 #define MBEDTLS_ERR_SSL_BAD_PROTOCOL_VERSION -0x6E80
116 /** The handshake negotiation failed. */
117 #define MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE -0x6E00
118 /** Session ticket has expired. */
119 #define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED -0x6D80
120 /** Public key type mismatch (eg, asked for RSA key exchange and presented EC key) */
121 #define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH -0x6D00
122 /** Unknown identity received (eg, PSK identity) */
123 #define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY -0x6C80
124 /** Internal error (eg, unexpected failure in lower-level module) */
125 #define MBEDTLS_ERR_SSL_INTERNAL_ERROR -0x6C00
126 /** A counter would wrap (eg, too many messages exchanged). */
127 #define MBEDTLS_ERR_SSL_COUNTER_WRAPPING -0x6B80
128 /** Unexpected message at ServerHello in renegotiation. */
129 #define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO -0x6B00
130 /** DTLS client must retry for hello verification */
131 #define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED -0x6A80
132 /** A buffer is too small to receive or write a message */
133 #define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL -0x6A00
134 /* Error space gap */
135 /** No data of requested type currently available on underlying transport. */
136 #define MBEDTLS_ERR_SSL_WANT_READ -0x6900
137 /** Connection requires a write call. */
138 #define MBEDTLS_ERR_SSL_WANT_WRITE -0x6880
139 /** The operation timed out. */
140 #define MBEDTLS_ERR_SSL_TIMEOUT -0x6800
141 /** The client initiated a reconnect from the same port. */
142 #define MBEDTLS_ERR_SSL_CLIENT_RECONNECT -0x6780
143 /** Record header looks valid but is not expected. */
144 #define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD -0x6700
145 /** The alert message received indicates a non-fatal error. */
146 #define MBEDTLS_ERR_SSL_NON_FATAL -0x6680
147 /** A field in a message was incorrect or inconsistent with other fields. */
148 #define MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER -0x6600
149 /** Internal-only message signaling that further message-processing should be done */
150 #define MBEDTLS_ERR_SSL_CONTINUE_PROCESSING -0x6580
151 /** The asynchronous operation is not completed yet. */
152 #define MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS -0x6500
153 /** Internal-only message signaling that a message arrived early. */
154 #define MBEDTLS_ERR_SSL_EARLY_MESSAGE -0x6480
155 /* Error space gap */
156 /* Error space gap */
157 /* Error space gap */
158 /* Error space gap */
159 /* Error space gap */
160 /* Error space gap */
161 /* Error space gap */
162 /* Error space gap */
163 /** An encrypted DTLS-frame with an unexpected CID was received. */
164 #define MBEDTLS_ERR_SSL_UNEXPECTED_CID -0x6000
165 /** An operation failed due to an unexpected version or configuration. */
166 #define MBEDTLS_ERR_SSL_VERSION_MISMATCH -0x5F00
167 /** Invalid value in SSL config */
168 #define MBEDTLS_ERR_SSL_BAD_CONFIG -0x5E80
169 /* Error space gap */
170 /** Attempt to verify a certificate without an expected hostname.
171 * This is usually insecure.
172 *
173 * In TLS clients, when a client authenticates a server through its
174 * certificate, the client normally checks three things:
175 * - the certificate chain must be valid;
176 * - the chain must start from a trusted CA;
177 * - the certificate must cover the server name that is expected by the client.
178 *
179 * Omitting any of these checks is generally insecure, and can allow a
180 * malicious server to impersonate a legitimate server.
181 *
182 * The third check may be safely skipped in some unusual scenarios,
183 * such as networks where eavesdropping is a risk but not active attacks,
184 * or a private PKI where the client equally trusts all servers that are
185 * accredited by the root CA.
186 *
187 * You should call mbedtls_ssl_set_hostname() with the expected server name
188 * before starting a TLS handshake on a client (unless the client is
189 * set up to only use PSK-based authentication, which does not rely on the
190 * host name). If you have determined that server name verification is not
191 * required for security in your scenario, call mbedtls_ssl_set_hostname()
192 * with \p NULL as the server name.
193 *
194 * This error is raised if all of the following conditions are met:
195 *
196 * - A TLS client is configured with the authentication mode
197 * #MBEDTLS_SSL_VERIFY_REQUIRED (default).
198 * - Certificate authentication is enabled.
199 * - The client does not call mbedtls_ssl_set_hostname().
200 * - The configuration option
201 * #MBEDTLS_SSL_CLI_ALLOW_WEAK_CERTIFICATE_VERIFICATION_WITHOUT_HOSTNAME
202 * is not enabled.
203 */
204 #define MBEDTLS_ERR_SSL_CERTIFICATE_VERIFICATION_WITHOUT_HOSTNAME -0x5D80
205
206 /*
207 * Constants from RFC 8446 for TLS 1.3 PSK modes
208 *
209 * Those are used in the Pre-Shared Key Exchange Modes extension.
210 * See Section 4.2.9 in RFC 8446.
211 */
212 #define MBEDTLS_SSL_TLS1_3_PSK_MODE_PURE 0 /* Pure PSK-based exchange */
213 #define MBEDTLS_SSL_TLS1_3_PSK_MODE_ECDHE 1 /* PSK+ECDHE-based exchange */
214
215 /*
216 * TLS 1.3 NamedGroup values
217 *
218 * From RF 8446
219 * enum {
220 * // Elliptic Curve Groups (ECDHE)
221 * secp256r1(0x0017), secp384r1(0x0018), secp521r1(0x0019),
222 * x25519(0x001D), x448(0x001E),
223 * // Finite Field Groups (DHE)
224 * ffdhe2048(0x0100), ffdhe3072(0x0101), ffdhe4096(0x0102),
225 * ffdhe6144(0x0103), ffdhe8192(0x0104),
226 * // Reserved Code Points
227 * ffdhe_private_use(0x01FC..0x01FF),
228 * ecdhe_private_use(0xFE00..0xFEFF),
229 * (0xFFFF)
230 * } NamedGroup;
231 *
232 */
233
234 /* Elliptic Curve Groups (ECDHE) */
235 #define MBEDTLS_SSL_IANA_TLS_GROUP_NONE 0
236 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP192K1 0x0012
237 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP192R1 0x0013
238 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP224K1 0x0014
239 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP224R1 0x0015
240 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP256K1 0x0016
241 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP256R1 0x0017
242 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP384R1 0x0018
243 #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP521R1 0x0019
244 #define MBEDTLS_SSL_IANA_TLS_GROUP_BP256R1 0x001A
245 #define MBEDTLS_SSL_IANA_TLS_GROUP_BP384R1 0x001B
246 #define MBEDTLS_SSL_IANA_TLS_GROUP_BP512R1 0x001C
247 #define MBEDTLS_SSL_IANA_TLS_GROUP_X25519 0x001D
248 #define MBEDTLS_SSL_IANA_TLS_GROUP_X448 0x001E
249 /* Finite Field Groups (DHE) */
250 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE2048 0x0100
251 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE3072 0x0101
252 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE4096 0x0102
253 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE6144 0x0103
254 #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE8192 0x0104
255
256 /*
257 * TLS 1.3 Key Exchange Modes
258 *
259 * Mbed TLS internal identifiers for use with the SSL configuration API
260 * mbedtls_ssl_conf_tls13_key_exchange_modes().
261 */
262
263 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK (1u << 0) /*!< Pure-PSK TLS 1.3 key exchange,
264 * encompassing both externally agreed PSKs
265 * as well as resumption PSKs. */
266 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL (1u << 1) /*!< Pure-Ephemeral TLS 1.3 key exchanges,
267 * including for example ECDHE and DHE
268 * key exchanges. */
269 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL (1u << 2) /*!< PSK-Ephemeral TLS 1.3 key exchanges,
270 * using both a PSK and an ephemeral
271 * key exchange. */
272
273 /* Convenience macros for sets of key exchanges. */
274 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_ALL \
275 (MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK | \
276 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL | \
277 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL) /*!< All TLS 1.3 key exchanges */
278 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL \
279 (MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK | \
280 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL) /*!< All PSK-based TLS 1.3 key exchanges */
281 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL \
282 (MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL | \
283 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL) /*!< All ephemeral TLS 1.3 key exchanges */
284
285 #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_NONE (0)
286
287 /*
288 * Various constants
289 */
290
291 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
292 /* These are the high and low bytes of ProtocolVersion as defined by:
293 * - RFC 5246: ProtocolVersion version = { 3, 3 }; // TLS v1.2
294 * - RFC 8446: see section 4.2.1
295 */
296 #define MBEDTLS_SSL_MAJOR_VERSION_3 3
297 #define MBEDTLS_SSL_MINOR_VERSION_3 3 /*!< TLS v1.2 */
298 #define MBEDTLS_SSL_MINOR_VERSION_4 4 /*!< TLS v1.3 */
299 #endif /* MBEDTLS_DEPRECATED_REMOVED */
300
301 #define MBEDTLS_SSL_TRANSPORT_STREAM 0 /*!< TLS */
302 #define MBEDTLS_SSL_TRANSPORT_DATAGRAM 1 /*!< DTLS */
303
304 #define MBEDTLS_SSL_MAX_HOST_NAME_LEN 255 /*!< Maximum host name defined in RFC 1035 */
305 #define MBEDTLS_SSL_MAX_ALPN_NAME_LEN 255 /*!< Maximum size in bytes of a protocol name in alpn ext., RFC 7301 */
306
307 #define MBEDTLS_SSL_MAX_ALPN_LIST_LEN 65535 /*!< Maximum size in bytes of list in alpn ext., RFC 7301 */
308
309 /* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
310 * NONE must be zero so that memset()ing structure to zero works */
311 #define MBEDTLS_SSL_MAX_FRAG_LEN_NONE 0 /*!< don't use this extension */
312 #define MBEDTLS_SSL_MAX_FRAG_LEN_512 1 /*!< MaxFragmentLength 2^9 */
313 #define MBEDTLS_SSL_MAX_FRAG_LEN_1024 2 /*!< MaxFragmentLength 2^10 */
314 #define MBEDTLS_SSL_MAX_FRAG_LEN_2048 3 /*!< MaxFragmentLength 2^11 */
315 #define MBEDTLS_SSL_MAX_FRAG_LEN_4096 4 /*!< MaxFragmentLength 2^12 */
316 #define MBEDTLS_SSL_MAX_FRAG_LEN_INVALID 5 /*!< first invalid value */
317
318 #define MBEDTLS_SSL_IS_CLIENT 0
319 #define MBEDTLS_SSL_IS_SERVER 1
320
321 #define MBEDTLS_SSL_EXTENDED_MS_DISABLED 0
322 #define MBEDTLS_SSL_EXTENDED_MS_ENABLED 1
323
324 #define MBEDTLS_SSL_CID_DISABLED 0
325 #define MBEDTLS_SSL_CID_ENABLED 1
326
327 #define MBEDTLS_SSL_ETM_DISABLED 0
328 #define MBEDTLS_SSL_ETM_ENABLED 1
329
330 #define MBEDTLS_SSL_COMPRESS_NULL 0
331
332 #define MBEDTLS_SSL_VERIFY_NONE 0
333 #define MBEDTLS_SSL_VERIFY_OPTIONAL 1
334 #define MBEDTLS_SSL_VERIFY_REQUIRED 2
335 #define MBEDTLS_SSL_VERIFY_UNSET 3 /* Used only for sni_authmode */
336
337 #define MBEDTLS_SSL_LEGACY_RENEGOTIATION 0
338 #define MBEDTLS_SSL_SECURE_RENEGOTIATION 1
339
340 #define MBEDTLS_SSL_RENEGOTIATION_DISABLED 0
341 #define MBEDTLS_SSL_RENEGOTIATION_ENABLED 1
342
343 #define MBEDTLS_SSL_ANTI_REPLAY_DISABLED 0
344 #define MBEDTLS_SSL_ANTI_REPLAY_ENABLED 1
345
346 #define MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED -1
347 #define MBEDTLS_SSL_RENEGO_MAX_RECORDS_DEFAULT 16
348
349 #define MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION 0
350 #define MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION 1
351 #define MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE 2
352
353 #define MBEDTLS_SSL_TRUNC_HMAC_DISABLED 0
354 #define MBEDTLS_SSL_TRUNC_HMAC_ENABLED 1
355 #define MBEDTLS_SSL_TRUNCATED_HMAC_LEN 10 /* 80 bits, rfc 6066 section 7 */
356
357 #define MBEDTLS_SSL_SESSION_TICKETS_DISABLED 0
358 #define MBEDTLS_SSL_SESSION_TICKETS_ENABLED 1
359
360 #define MBEDTLS_SSL_TLS1_3_SIGNAL_NEW_SESSION_TICKETS_DISABLED 0
361 #define MBEDTLS_SSL_TLS1_3_SIGNAL_NEW_SESSION_TICKETS_ENABLED 1
362
363 #define MBEDTLS_SSL_PRESET_DEFAULT 0
364 #define MBEDTLS_SSL_PRESET_SUITEB 2
365
366 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED 1
367 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 0
368
369 #define MBEDTLS_SSL_EARLY_DATA_DISABLED 0
370 #define MBEDTLS_SSL_EARLY_DATA_ENABLED 1
371
372 #define MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED 0
373 #define MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED 1
374
375 #define MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_CLIENT 1
376 #define MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER 0
377
378 #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS)
379 #if defined(PSA_WANT_ALG_SHA_384)
380 #define MBEDTLS_SSL_TLS1_3_TICKET_RESUMPTION_KEY_LEN 48
381 #elif defined(PSA_WANT_ALG_SHA_256)
382 #define MBEDTLS_SSL_TLS1_3_TICKET_RESUMPTION_KEY_LEN 32
383 #endif
384 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */
385 /*
386 * Default range for DTLS retransmission timer value, in milliseconds.
387 * RFC 6347 4.2.4.1 says from 1 second to 60 seconds.
388 */
389 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN 1000
390 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX 60000
391
392 /*
393 * Whether early data record should be discarded or not and how.
394 *
395 * The client has indicated early data and the server has rejected them.
396 * The server has then to skip past early data by either:
397 * - attempting to deprotect received records using the handshake traffic
398 * key, discarding records which fail deprotection (up to the configured
399 * max_early_data_size). Once a record is deprotected successfully,
400 * it is treated as the start of the client's second flight and the
401 * server proceeds as with an ordinary 1-RTT handshake.
402 * - skipping all records with an external content type of
403 * "application_data" (indicating that they are encrypted), up to the
404 * configured max_early_data_size. This is the expected behavior if the
405 * server has sent an HelloRetryRequest message. The server ignores
406 * application data message before 2nd ClientHello.
407 */
408 #define MBEDTLS_SSL_EARLY_DATA_NO_DISCARD 0
409 #define MBEDTLS_SSL_EARLY_DATA_TRY_TO_DEPROTECT_AND_DISCARD 1
410 #define MBEDTLS_SSL_EARLY_DATA_DISCARD 2
411
412 /**
413 * \name SECTION: Module settings
414 *
415 * The configuration options you can set for this module are in this section.
416 * Either change them in mbedtls_config.h or define them on the compiler command line.
417 * \{
418 */
419
420 /*
421 * Maximum fragment length in bytes,
422 * determines the size of each of the two internal I/O buffers.
423 *
424 * Note: the RFC defines the default size of SSL / TLS messages. If you
425 * change the value here, other clients / servers may not be able to
426 * communicate with you anymore. Only change this value if you control
427 * both sides of the connection and have it reduced at both sides, or
428 * if you're using the Max Fragment Length extension and you know all your
429 * peers are using it too!
430 */
431 #if !defined(MBEDTLS_SSL_IN_CONTENT_LEN)
432 #define MBEDTLS_SSL_IN_CONTENT_LEN 16384
433 #endif
434
435 #if !defined(MBEDTLS_SSL_OUT_CONTENT_LEN)
436 #define MBEDTLS_SSL_OUT_CONTENT_LEN 16384
437 #endif
438
439 /*
440 * Maximum number of heap-allocated bytes for the purpose of
441 * DTLS handshake message reassembly and future message buffering.
442 */
443 #if !defined(MBEDTLS_SSL_DTLS_MAX_BUFFERING)
444 #define MBEDTLS_SSL_DTLS_MAX_BUFFERING 32768
445 #endif
446
447 /*
448 * Maximum length of CIDs for incoming and outgoing messages.
449 */
450 #if !defined(MBEDTLS_SSL_CID_IN_LEN_MAX)
451 #define MBEDTLS_SSL_CID_IN_LEN_MAX 32
452 #endif
453
454 #if !defined(MBEDTLS_SSL_CID_OUT_LEN_MAX)
455 #define MBEDTLS_SSL_CID_OUT_LEN_MAX 32
456 #endif
457
458 #if !defined(MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY)
459 #define MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 16
460 #endif
461
462 #if !defined(MBEDTLS_SSL_MAX_EARLY_DATA_SIZE)
463 #define MBEDTLS_SSL_MAX_EARLY_DATA_SIZE 1024
464 #endif
465
466 #if !defined(MBEDTLS_SSL_TLS1_3_TICKET_AGE_TOLERANCE)
467 #define MBEDTLS_SSL_TLS1_3_TICKET_AGE_TOLERANCE 6000
468 #endif
469
470 #if !defined(MBEDTLS_SSL_TLS1_3_TICKET_NONCE_LENGTH)
471 #define MBEDTLS_SSL_TLS1_3_TICKET_NONCE_LENGTH 32
472 #endif
473
474 #if !defined(MBEDTLS_SSL_TLS1_3_DEFAULT_NEW_SESSION_TICKETS)
475 #define MBEDTLS_SSL_TLS1_3_DEFAULT_NEW_SESSION_TICKETS 1
476 #endif
477
478 /** \} name SECTION: Module settings */
479
480 /*
481 * Default to standard CID mode
482 */
483 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) && \
484 !defined(MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT)
485 #define MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT 0
486 #endif
487
488 /*
489 * Length of the verify data for secure renegotiation
490 */
491 #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 12
492
493 /*
494 * Signaling ciphersuite values (SCSV)
495 */
496 #define MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO 0xFF /**< renegotiation info ext */
497
498 /*
499 * Supported Signature and Hash algorithms (For TLS 1.2)
500 * RFC 5246 section 7.4.1.4.1
501 */
502 #define MBEDTLS_SSL_HASH_NONE 0
503 #define MBEDTLS_SSL_HASH_MD5 1
504 #define MBEDTLS_SSL_HASH_SHA1 2
505 #define MBEDTLS_SSL_HASH_SHA224 3
506 #define MBEDTLS_SSL_HASH_SHA256 4
507 #define MBEDTLS_SSL_HASH_SHA384 5
508 #define MBEDTLS_SSL_HASH_SHA512 6
509
510 #define MBEDTLS_SSL_SIG_ANON 0
511 #define MBEDTLS_SSL_SIG_RSA 1
512 #define MBEDTLS_SSL_SIG_ECDSA 3
513
514 /*
515 * TLS 1.3 signature algorithms
516 * RFC 8446, Section 4.2.3
517 */
518
519 /* RSASSA-PKCS1-v1_5 algorithms */
520 #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA256 0x0401
521 #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA384 0x0501
522 #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA512 0x0601
523
524 /* ECDSA algorithms */
525 #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP256R1_SHA256 0x0403
526 #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP384R1_SHA384 0x0503
527 #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP521R1_SHA512 0x0603
528
529 /* RSASSA-PSS algorithms with public key OID rsaEncryption */
530 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA256 0x0804
531 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA384 0x0805
532 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA512 0x0806
533
534 /* EdDSA algorithms */
535 #define MBEDTLS_TLS1_3_SIG_ED25519 0x0807
536 #define MBEDTLS_TLS1_3_SIG_ED448 0x0808
537
538 /* RSASSA-PSS algorithms with public key OID RSASSA-PSS */
539 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA256 0x0809
540 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA384 0x080A
541 #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA512 0x080B
542
543 /* LEGACY ALGORITHMS */
544 #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA1 0x0201
545 #define MBEDTLS_TLS1_3_SIG_ECDSA_SHA1 0x0203
546
547 #define MBEDTLS_TLS1_3_SIG_NONE 0x0
548
549 /*
550 * Client Certificate Types
551 * RFC 5246 section 7.4.4 plus RFC 4492 section 5.5
552 */
553 #define MBEDTLS_SSL_CERT_TYPE_RSA_SIGN 1
554 #define MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN 64
555
556 /*
557 * Message, alert and handshake types
558 */
559 #define MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC 20
560 #define MBEDTLS_SSL_MSG_ALERT 21
561 #define MBEDTLS_SSL_MSG_HANDSHAKE 22
562 #define MBEDTLS_SSL_MSG_APPLICATION_DATA 23
563 #define MBEDTLS_SSL_MSG_CID 25
564
565 #define MBEDTLS_SSL_ALERT_LEVEL_WARNING 1
566 #define MBEDTLS_SSL_ALERT_LEVEL_FATAL 2
567
568 #define MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY 0 /* 0x00 */
569 #define MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE 10 /* 0x0A */
570 #define MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC 20 /* 0x14 */
571 #define MBEDTLS_SSL_ALERT_MSG_DECRYPTION_FAILED 21 /* 0x15 */
572 #define MBEDTLS_SSL_ALERT_MSG_RECORD_OVERFLOW 22 /* 0x16 */
573 #define MBEDTLS_SSL_ALERT_MSG_DECOMPRESSION_FAILURE 30 /* 0x1E */
574 #define MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE 40 /* 0x28 */
575 #define MBEDTLS_SSL_ALERT_MSG_NO_CERT 41 /* 0x29 */
576 #define MBEDTLS_SSL_ALERT_MSG_BAD_CERT 42 /* 0x2A */
577 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT 43 /* 0x2B */
578 #define MBEDTLS_SSL_ALERT_MSG_CERT_REVOKED 44 /* 0x2C */
579 #define MBEDTLS_SSL_ALERT_MSG_CERT_EXPIRED 45 /* 0x2D */
580 #define MBEDTLS_SSL_ALERT_MSG_CERT_UNKNOWN 46 /* 0x2E */
581 #define MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER 47 /* 0x2F */
582 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_CA 48 /* 0x30 */
583 #define MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED 49 /* 0x31 */
584 #define MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR 50 /* 0x32 */
585 #define MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR 51 /* 0x33 */
586 #define MBEDTLS_SSL_ALERT_MSG_EXPORT_RESTRICTION 60 /* 0x3C */
587 #define MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION 70 /* 0x46 */
588 #define MBEDTLS_SSL_ALERT_MSG_INSUFFICIENT_SECURITY 71 /* 0x47 */
589 #define MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR 80 /* 0x50 */
590 #define MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK 86 /* 0x56 */
591 #define MBEDTLS_SSL_ALERT_MSG_USER_CANCELED 90 /* 0x5A */
592 #define MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION 100 /* 0x64 */
593 #define MBEDTLS_SSL_ALERT_MSG_MISSING_EXTENSION 109 /* 0x6d -- new in TLS 1.3 */
594 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT 110 /* 0x6E */
595 #define MBEDTLS_SSL_ALERT_MSG_UNRECOGNIZED_NAME 112 /* 0x70 */
596 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY 115 /* 0x73 */
597 #define MBEDTLS_SSL_ALERT_MSG_CERT_REQUIRED 116 /* 0x74 */
598 #define MBEDTLS_SSL_ALERT_MSG_NO_APPLICATION_PROTOCOL 120 /* 0x78 */
599
600 #define MBEDTLS_SSL_HS_HELLO_REQUEST 0
601 #define MBEDTLS_SSL_HS_CLIENT_HELLO 1
602 #define MBEDTLS_SSL_HS_SERVER_HELLO 2
603 #define MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST 3
604 #define MBEDTLS_SSL_HS_NEW_SESSION_TICKET 4
605 #define MBEDTLS_SSL_HS_END_OF_EARLY_DATA 5
606 #define MBEDTLS_SSL_HS_ENCRYPTED_EXTENSIONS 8
607 #define MBEDTLS_SSL_HS_CERTIFICATE 11
608 #define MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE 12
609 #define MBEDTLS_SSL_HS_CERTIFICATE_REQUEST 13
610 #define MBEDTLS_SSL_HS_SERVER_HELLO_DONE 14
611 #define MBEDTLS_SSL_HS_CERTIFICATE_VERIFY 15
612 #define MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE 16
613 #define MBEDTLS_SSL_HS_FINISHED 20
614 #define MBEDTLS_SSL_HS_MESSAGE_HASH 254
615
616 /*
617 * TLS extensions
618 */
619 #define MBEDTLS_TLS_EXT_SERVERNAME 0
620 #define MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME 0
621
622 #define MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH 1
623
624 #define MBEDTLS_TLS_EXT_TRUNCATED_HMAC 4
625 #define MBEDTLS_TLS_EXT_STATUS_REQUEST 5 /* RFC 6066 TLS 1.2 and 1.3 */
626
627 #define MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES 10
628 #define MBEDTLS_TLS_EXT_SUPPORTED_GROUPS 10 /* RFC 8422,7919 TLS 1.2 and 1.3 */
629 #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS 11
630
631 #define MBEDTLS_TLS_EXT_SIG_ALG 13 /* RFC 8446 TLS 1.3 */
632 #define MBEDTLS_TLS_EXT_USE_SRTP 14
633 #define MBEDTLS_TLS_EXT_HEARTBEAT 15 /* RFC 6520 TLS 1.2 and 1.3 */
634 #define MBEDTLS_TLS_EXT_ALPN 16
635
636 #define MBEDTLS_TLS_EXT_SCT 18 /* RFC 6962 TLS 1.2 and 1.3 */
637 #define MBEDTLS_TLS_EXT_CLI_CERT_TYPE 19 /* RFC 7250 TLS 1.2 and 1.3 */
638 #define MBEDTLS_TLS_EXT_SERV_CERT_TYPE 20 /* RFC 7250 TLS 1.2 and 1.3 */
639 #define MBEDTLS_TLS_EXT_PADDING 21 /* RFC 7685 TLS 1.2 and 1.3 */
640 #define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC 22 /* 0x16 */
641 #define MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET 0x0017 /* 23 */
642
643 #define MBEDTLS_TLS_EXT_RECORD_SIZE_LIMIT 28 /* RFC 8449 (implemented for TLS 1.3 only) */
644
645 #define MBEDTLS_TLS_EXT_SESSION_TICKET 35
646
647 #define MBEDTLS_TLS_EXT_PRE_SHARED_KEY 41 /* RFC 8446 TLS 1.3 */
648 #define MBEDTLS_TLS_EXT_EARLY_DATA 42 /* RFC 8446 TLS 1.3 */
649 #define MBEDTLS_TLS_EXT_SUPPORTED_VERSIONS 43 /* RFC 8446 TLS 1.3 */
650 #define MBEDTLS_TLS_EXT_COOKIE 44 /* RFC 8446 TLS 1.3 */
651 #define MBEDTLS_TLS_EXT_PSK_KEY_EXCHANGE_MODES 45 /* RFC 8446 TLS 1.3 */
652
653 #define MBEDTLS_TLS_EXT_CERT_AUTH 47 /* RFC 8446 TLS 1.3 */
654 #define MBEDTLS_TLS_EXT_OID_FILTERS 48 /* RFC 8446 TLS 1.3 */
655 #define MBEDTLS_TLS_EXT_POST_HANDSHAKE_AUTH 49 /* RFC 8446 TLS 1.3 */
656 #define MBEDTLS_TLS_EXT_SIG_ALG_CERT 50 /* RFC 8446 TLS 1.3 */
657 #define MBEDTLS_TLS_EXT_KEY_SHARE 51 /* RFC 8446 TLS 1.3 */
658
659 /*
660 * MBEDTLS_TLS_EXT_CID is required only when
661 * MBEDTLS_SSL_DTLS_CONNECTION_ID is defined.
662 */
663 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
664 #if MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT == 0
665 #define MBEDTLS_TLS_EXT_CID 54 /* RFC 9146 DTLS 1.2 CID */
666 #else
667 #define MBEDTLS_TLS_EXT_CID 254 /* Pre-RFC 9146 DTLS 1.2 CID */
668 #endif
669 #endif
670
671 #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP 256 /* experimental */
672
673 #define MBEDTLS_TLS_EXT_RENEGOTIATION_INFO 0xFF01
674
675 /*
676 * Size defines
677 */
678 #if !defined(MBEDTLS_PSK_MAX_LEN)
679 /*
680 * If the library supports TLS 1.3 tickets and the cipher suite
681 * TLS1-3-AES-256-GCM-SHA384, set the PSK maximum length to 48 instead of 32.
682 * That way, the TLS 1.3 client and server are able to resume sessions where
683 * the cipher suite is TLS1-3-AES-256-GCM-SHA384 (pre-shared keys are 48
684 * bytes long in that case).
685 */
686 #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && \
687 defined(MBEDTLS_SSL_SESSION_TICKETS) && \
688 defined(MBEDTLS_SSL_HAVE_AES) && defined(MBEDTLS_SSL_HAVE_GCM) && \
689 defined(MBEDTLS_MD_CAN_SHA384)
690 #define MBEDTLS_PSK_MAX_LEN 48 /* 384 bits */
691 #else
692 #define MBEDTLS_PSK_MAX_LEN 32 /* 256 bits */
693 #endif
694 #endif /* !MBEDTLS_PSK_MAX_LEN */
695
696 /* Dummy type used only for its size */
697 union mbedtls_ssl_premaster_secret {
698 unsigned char dummy; /* Make the union non-empty even with SSL disabled */
699 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
700 unsigned char _pms_rsa[48]; /* RFC 5246 8.1.1 */
701 #endif
702 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)
703 unsigned char _pms_dhm[MBEDTLS_MPI_MAX_SIZE]; /* RFC 5246 8.1.2 */
704 #endif
705 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
706 defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
707 defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
708 defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
709 unsigned char _pms_ecdh[MBEDTLS_ECP_MAX_BYTES]; /* RFC 4492 5.10 */
710 #endif
711 #if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
712 unsigned char _pms_psk[4 + 2 * MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 2 */
713 #endif
714 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
715 unsigned char _pms_dhe_psk[4 + MBEDTLS_MPI_MAX_SIZE
716 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 3 */
717 #endif
718 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
719 unsigned char _pms_rsa_psk[52 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 4 */
720 #endif
721 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
722 unsigned char _pms_ecdhe_psk[4 + MBEDTLS_ECP_MAX_BYTES
723 + MBEDTLS_PSK_MAX_LEN]; /* RFC 5489 2 */
724 #endif
725 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
726 unsigned char _pms_ecjpake[32]; /* Thread spec: SHA-256 output */
727 #endif
728 };
729
730 #define MBEDTLS_PREMASTER_SIZE sizeof(union mbedtls_ssl_premaster_secret)
731
732 #define MBEDTLS_TLS1_3_MD_MAX_SIZE PSA_HASH_MAX_SIZE
733
734
735 /* Length in number of bytes of the TLS sequence number */
736 #define MBEDTLS_SSL_SEQUENCE_NUMBER_LEN 8
737
738 /* Helper to state that client_random and server_random need to be stored
739 * after the handshake is complete. This is required for context serialization
740 * and for the keying material exporter in TLS 1.2. */
741 #if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION) || \
742 (defined(MBEDTLS_SSL_KEYING_MATERIAL_EXPORT) && defined(MBEDTLS_SSL_PROTO_TLS1_2))
743 #define MBEDTLS_SSL_KEEP_RANDBYTES
744 #endif
745
746 #ifdef __cplusplus
747 extern "C" {
748 #endif
749
750 /*
751 * SSL state machine
752 */
753 typedef enum {
754 MBEDTLS_SSL_HELLO_REQUEST,
755 MBEDTLS_SSL_CLIENT_HELLO,
756 MBEDTLS_SSL_SERVER_HELLO,
757 MBEDTLS_SSL_SERVER_CERTIFICATE,
758 MBEDTLS_SSL_SERVER_KEY_EXCHANGE,
759 MBEDTLS_SSL_CERTIFICATE_REQUEST,
760 MBEDTLS_SSL_SERVER_HELLO_DONE,
761 MBEDTLS_SSL_CLIENT_CERTIFICATE,
762 MBEDTLS_SSL_CLIENT_KEY_EXCHANGE,
763 MBEDTLS_SSL_CERTIFICATE_VERIFY,
764 MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC,
765 MBEDTLS_SSL_CLIENT_FINISHED,
766 MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC,
767 MBEDTLS_SSL_SERVER_FINISHED,
768 MBEDTLS_SSL_FLUSH_BUFFERS,
769 MBEDTLS_SSL_HANDSHAKE_WRAPUP,
770 MBEDTLS_SSL_NEW_SESSION_TICKET,
771 MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT,
772 MBEDTLS_SSL_HELLO_RETRY_REQUEST,
773 MBEDTLS_SSL_ENCRYPTED_EXTENSIONS,
774 MBEDTLS_SSL_END_OF_EARLY_DATA,
775 MBEDTLS_SSL_CLIENT_CERTIFICATE_VERIFY,
776 MBEDTLS_SSL_CLIENT_CCS_AFTER_SERVER_FINISHED,
777 MBEDTLS_SSL_CLIENT_CCS_BEFORE_2ND_CLIENT_HELLO,
778 MBEDTLS_SSL_SERVER_CCS_AFTER_SERVER_HELLO,
779 MBEDTLS_SSL_CLIENT_CCS_AFTER_CLIENT_HELLO,
780 MBEDTLS_SSL_SERVER_CCS_AFTER_HELLO_RETRY_REQUEST,
781 MBEDTLS_SSL_HANDSHAKE_OVER,
782 MBEDTLS_SSL_TLS1_3_NEW_SESSION_TICKET,
783 MBEDTLS_SSL_TLS1_3_NEW_SESSION_TICKET_FLUSH,
784 }
785 mbedtls_ssl_states;
786
787 /*
788 * Early data status, client side only.
789 */
790
791 #if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C)
792 typedef enum {
793 /*
794 * See documentation of mbedtls_ssl_get_early_data_status().
795 */
796 MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_INDICATED,
797 MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED,
798 MBEDTLS_SSL_EARLY_DATA_STATUS_REJECTED,
799 } mbedtls_ssl_early_data_status;
800 #endif /* MBEDTLS_SSL_EARLY_DATA && MBEDTLS_SSL_CLI_C */
801
802 /**
803 * \brief Callback type: send data on the network.
804 *
805 * \note That callback may be either blocking or non-blocking.
806 *
807 * \param ctx Context for the send callback (typically a file descriptor)
808 * \param buf Buffer holding the data to send
809 * \param len Length of the data to send
810 *
811 * \return The callback must return the number of bytes sent if any,
812 * or a non-zero error code.
813 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_WRITE
814 * must be returned when the operation would block.
815 *
816 * \note The callback is allowed to send fewer bytes than requested.
817 * It must always return the number of bytes actually sent.
818 */
819 typedef int mbedtls_ssl_send_t(void *ctx,
820 const unsigned char *buf,
821 size_t len);
822
823 /**
824 * \brief Callback type: receive data from the network.
825 *
826 * \note That callback may be either blocking or non-blocking.
827 *
828 * \param ctx Context for the receive callback (typically a file
829 * descriptor)
830 * \param buf Buffer to write the received data to
831 * \param len Length of the receive buffer
832 *
833 * \returns If data has been received, the positive number of bytes received.
834 * \returns \c 0 if the connection has been closed.
835 * \returns If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ
836 * must be returned when the operation would block.
837 * \returns Another negative error code on other kinds of failures.
838 *
839 * \note The callback may receive fewer bytes than the length of the
840 * buffer. It must always return the number of bytes actually
841 * received and written to the buffer.
842 */
843 typedef int mbedtls_ssl_recv_t(void *ctx,
844 unsigned char *buf,
845 size_t len);
846
847 /**
848 * \brief Callback type: receive data from the network, with timeout
849 *
850 * \note That callback must block until data is received, or the
851 * timeout delay expires, or the operation is interrupted by a
852 * signal.
853 *
854 * \param ctx Context for the receive callback (typically a file descriptor)
855 * \param buf Buffer to write the received data to
856 * \param len Length of the receive buffer
857 * \param timeout Maximum number of milliseconds to wait for data
858 * 0 means no timeout (potentially waiting forever)
859 *
860 * \return The callback must return the number of bytes received,
861 * or a non-zero error code:
862 * \c MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out,
863 * \c MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal.
864 *
865 * \note The callback may receive fewer bytes than the length of the
866 * buffer. It must always return the number of bytes actually
867 * received and written to the buffer.
868 */
869 typedef int mbedtls_ssl_recv_timeout_t(void *ctx,
870 unsigned char *buf,
871 size_t len,
872 uint32_t timeout);
873 /**
874 * \brief Callback type: set a pair of timers/delays to watch
875 *
876 * \param ctx Context pointer
877 * \param int_ms Intermediate delay in milliseconds
878 * \param fin_ms Final delay in milliseconds
879 * 0 cancels the current timer.
880 *
881 * \note This callback must at least store the necessary information
882 * for the associated \c mbedtls_ssl_get_timer_t callback to
883 * return correct information.
884 *
885 * \note If using an event-driven style of programming, an event must
886 * be generated when the final delay is passed. The event must
887 * cause a call to \c mbedtls_ssl_handshake() with the proper
888 * SSL context to be scheduled. Care must be taken to ensure
889 * that at most one such call happens at a time.
890 *
891 * \note Only one timer at a time must be running. Calling this
892 * function while a timer is running must cancel it. Cancelled
893 * timers must not generate any event.
894 */
895 typedef void mbedtls_ssl_set_timer_t(void *ctx,
896 uint32_t int_ms,
897 uint32_t fin_ms);
898
899 /**
900 * \brief Callback type: get status of timers/delays
901 *
902 * \param ctx Context pointer
903 *
904 * \return This callback must return:
905 * -1 if cancelled (fin_ms == 0),
906 * 0 if none of the delays have passed,
907 * 1 if only the intermediate delay has passed,
908 * 2 if the final delay has passed.
909 */
910 typedef int mbedtls_ssl_get_timer_t(void *ctx);
911
912 /* Defined below */
913 typedef struct mbedtls_ssl_session mbedtls_ssl_session;
914 typedef struct mbedtls_ssl_context mbedtls_ssl_context;
915 typedef struct mbedtls_ssl_config mbedtls_ssl_config;
916
917 /* Defined in library/ssl_misc.h */
918 typedef struct mbedtls_ssl_transform mbedtls_ssl_transform;
919 typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params;
920 typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t;
921 #if defined(MBEDTLS_X509_CRT_PARSE_C)
922 typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert;
923 #endif
924 #if defined(MBEDTLS_SSL_PROTO_DTLS)
925 typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item;
926 #endif
927
928 #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS)
929 #define MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_RESUMPTION \
930 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK /* 1U << 0 */
931 #define MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_EPHEMERAL_RESUMPTION \
932 MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL /* 1U << 2 */
933 #define MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_EARLY_DATA (1U << 3)
934
935 #define MBEDTLS_SSL_TLS1_3_TICKET_FLAGS_MASK \
936 (MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_RESUMPTION | \
937 MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_EPHEMERAL_RESUMPTION | \
938 MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_EARLY_DATA)
939 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */
940
941 /**
942 * \brief Callback type: server-side session cache getter
943 *
944 * The session cache is logically a key value store, with
945 * keys being session IDs and values being instances of
946 * mbedtls_ssl_session.
947 *
948 * This callback retrieves an entry in this key-value store.
949 *
950 * \param data The address of the session cache structure to query.
951 * \param session_id The buffer holding the session ID to query.
952 * \param session_id_len The length of \p session_id in Bytes.
953 * \param session The address of the session structure to populate.
954 * It is initialized with mbdtls_ssl_session_init(),
955 * and the callback must always leave it in a state
956 * where it can safely be freed via
957 * mbedtls_ssl_session_free() independent of the
958 * return code of this function.
959 *
960 * \return \c 0 on success
961 * \return A non-zero return value on failure.
962 *
963 */
964 typedef int mbedtls_ssl_cache_get_t(void *data,
965 unsigned char const *session_id,
966 size_t session_id_len,
967 mbedtls_ssl_session *session);
968 /**
969 * \brief Callback type: server-side session cache setter
970 *
971 * The session cache is logically a key value store, with
972 * keys being session IDs and values being instances of
973 * mbedtls_ssl_session.
974 *
975 * This callback sets an entry in this key-value store.
976 *
977 * \param data The address of the session cache structure to modify.
978 * \param session_id The buffer holding the session ID to query.
979 * \param session_id_len The length of \p session_id in Bytes.
980 * \param session The address of the session to be stored in the
981 * session cache.
982 *
983 * \return \c 0 on success
984 * \return A non-zero return value on failure.
985 */
986 typedef int mbedtls_ssl_cache_set_t(void *data,
987 unsigned char const *session_id,
988 size_t session_id_len,
989 const mbedtls_ssl_session *session);
990
991 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
992 #if defined(MBEDTLS_X509_CRT_PARSE_C)
993 /**
994 * \brief Callback type: start external signature operation.
995 *
996 * This callback is called during an SSL handshake to start
997 * a signature decryption operation using an
998 * external processor. The parameter \p cert contains
999 * the public key; it is up to the callback function to
1000 * determine how to access the associated private key.
1001 *
1002 * This function typically sends or enqueues a request, and
1003 * does not wait for the operation to complete. This allows
1004 * the handshake step to be non-blocking.
1005 *
1006 * The parameters \p ssl and \p cert are guaranteed to remain
1007 * valid throughout the handshake. On the other hand, this
1008 * function must save the contents of \p hash if the value
1009 * is needed for later processing, because the \p hash buffer
1010 * is no longer valid after this function returns.
1011 *
1012 * This function may call mbedtls_ssl_set_async_operation_data()
1013 * to store an operation context for later retrieval
1014 * by the resume or cancel callback.
1015 *
1016 * \note For RSA signatures, this function must produce output
1017 * that is consistent with PKCS#1 v1.5 in the same way as
1018 * mbedtls_rsa_pkcs1_sign(). Before the private key operation,
1019 * apply the padding steps described in RFC 8017, section 9.2
1020 * "EMSA-PKCS1-v1_5" as follows.
1021 * - If \p md_alg is #MBEDTLS_MD_NONE, apply the PKCS#1 v1.5
1022 * encoding, treating \p hash as the DigestInfo to be
1023 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
1024 * from step 3, with `T = hash` and `tLen = hash_len`.
1025 * - If `md_alg != MBEDTLS_MD_NONE`, apply the PKCS#1 v1.5
1026 * encoding, treating \p hash as the hash to be encoded and
1027 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
1028 * from step 2, with `digestAlgorithm` obtained by calling
1029 * mbedtls_oid_get_oid_by_md() on \p md_alg.
1030 *
1031 * \note For ECDSA signatures, the output format is the DER encoding
1032 * `Ecdsa-Sig-Value` defined in
1033 * [RFC 4492 section 5.4](https://tools.ietf.org/html/rfc4492#section-5.4).
1034 *
1035 * \param ssl The SSL connection instance. It should not be
1036 * modified other than via
1037 * mbedtls_ssl_set_async_operation_data().
1038 * \param cert Certificate containing the public key.
1039 * In simple cases, this is one of the pointers passed to
1040 * mbedtls_ssl_conf_own_cert() when configuring the SSL
1041 * connection. However, if other callbacks are used, this
1042 * property may not hold. For example, if an SNI callback
1043 * is registered with mbedtls_ssl_conf_sni(), then
1044 * this callback determines what certificate is used.
1045 * \param md_alg Hash algorithm.
1046 * \param hash Buffer containing the hash. This buffer is
1047 * no longer valid when the function returns.
1048 * \param hash_len Size of the \c hash buffer in bytes.
1049 *
1050 * \return 0 if the operation was started successfully and the SSL
1051 * stack should call the resume callback immediately.
1052 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
1053 * was started successfully and the SSL stack should return
1054 * immediately without calling the resume callback yet.
1055 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
1056 * processor does not support this key. The SSL stack will
1057 * use the private key object instead.
1058 * \return Any other error indicates a fatal failure and is
1059 * propagated up the call chain. The callback should
1060 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
1061 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
1062 * directed in the documentation of this callback.
1063 */
1064 typedef int mbedtls_ssl_async_sign_t(mbedtls_ssl_context *ssl,
1065 mbedtls_x509_crt *cert,
1066 mbedtls_md_type_t md_alg,
1067 const unsigned char *hash,
1068 size_t hash_len);
1069
1070 /**
1071 * \brief Callback type: start external decryption operation.
1072 *
1073 * This callback is called during an SSL handshake to start
1074 * an RSA decryption operation using an
1075 * external processor. The parameter \p cert contains
1076 * the public key; it is up to the callback function to
1077 * determine how to access the associated private key.
1078 *
1079 * This function typically sends or enqueues a request, and
1080 * does not wait for the operation to complete. This allows
1081 * the handshake step to be non-blocking.
1082 *
1083 * The parameters \p ssl and \p cert are guaranteed to remain
1084 * valid throughout the handshake. On the other hand, this
1085 * function must save the contents of \p input if the value
1086 * is needed for later processing, because the \p input buffer
1087 * is no longer valid after this function returns.
1088 *
1089 * This function may call mbedtls_ssl_set_async_operation_data()
1090 * to store an operation context for later retrieval
1091 * by the resume or cancel callback.
1092 *
1093 * \warning RSA decryption as used in TLS is subject to a potential
1094 * timing side channel attack first discovered by Bleichenbacher
1095 * in 1998. This attack can be remotely exploitable
1096 * in practice. To avoid this attack, you must ensure that
1097 * if the callback performs an RSA decryption, the time it
1098 * takes to execute and return the result does not depend
1099 * on whether the RSA decryption succeeded or reported
1100 * invalid padding.
1101 *
1102 * \param ssl The SSL connection instance. It should not be
1103 * modified other than via
1104 * mbedtls_ssl_set_async_operation_data().
1105 * \param cert Certificate containing the public key.
1106 * In simple cases, this is one of the pointers passed to
1107 * mbedtls_ssl_conf_own_cert() when configuring the SSL
1108 * connection. However, if other callbacks are used, this
1109 * property may not hold. For example, if an SNI callback
1110 * is registered with mbedtls_ssl_conf_sni(), then
1111 * this callback determines what certificate is used.
1112 * \param input Buffer containing the input ciphertext. This buffer
1113 * is no longer valid when the function returns.
1114 * \param input_len Size of the \p input buffer in bytes.
1115 *
1116 * \return 0 if the operation was started successfully and the SSL
1117 * stack should call the resume callback immediately.
1118 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
1119 * was started successfully and the SSL stack should return
1120 * immediately without calling the resume callback yet.
1121 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
1122 * processor does not support this key. The SSL stack will
1123 * use the private key object instead.
1124 * \return Any other error indicates a fatal failure and is
1125 * propagated up the call chain. The callback should
1126 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
1127 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
1128 * directed in the documentation of this callback.
1129 */
1130 typedef int mbedtls_ssl_async_decrypt_t(mbedtls_ssl_context *ssl,
1131 mbedtls_x509_crt *cert,
1132 const unsigned char *input,
1133 size_t input_len);
1134 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1135
1136 /**
1137 * \brief Callback type: resume external operation.
1138 *
1139 * This callback is called during an SSL handshake to resume
1140 * an external operation started by the
1141 * ::mbedtls_ssl_async_sign_t or
1142 * ::mbedtls_ssl_async_decrypt_t callback.
1143 *
1144 * This function typically checks the status of a pending
1145 * request or causes the request queue to make progress, and
1146 * does not wait for the operation to complete. This allows
1147 * the handshake step to be non-blocking.
1148 *
1149 * This function may call mbedtls_ssl_get_async_operation_data()
1150 * to retrieve an operation context set by the start callback.
1151 * It may call mbedtls_ssl_set_async_operation_data() to modify
1152 * this context.
1153 *
1154 * Note that when this function returns a status other than
1155 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, it must free any
1156 * resources associated with the operation.
1157 *
1158 * \param ssl The SSL connection instance. It should not be
1159 * modified other than via
1160 * mbedtls_ssl_set_async_operation_data().
1161 * \param output Buffer containing the output (signature or decrypted
1162 * data) on success.
1163 * \param output_len On success, number of bytes written to \p output.
1164 * \param output_size Size of the \p output buffer in bytes.
1165 *
1166 * \return 0 if output of the operation is available in the
1167 * \p output buffer.
1168 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
1169 * is still in progress. Subsequent requests for progress
1170 * on the SSL connection will call the resume callback
1171 * again.
1172 * \return Any other error means that the operation is aborted.
1173 * The SSL handshake is aborted. The callback should
1174 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
1175 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
1176 * directed in the documentation of this callback.
1177 */
1178 typedef int mbedtls_ssl_async_resume_t(mbedtls_ssl_context *ssl,
1179 unsigned char *output,
1180 size_t *output_len,
1181 size_t output_size);
1182
1183 /**
1184 * \brief Callback type: cancel external operation.
1185 *
1186 * This callback is called if an SSL connection is closed
1187 * while an asynchronous operation is in progress. Note that
1188 * this callback is not called if the
1189 * ::mbedtls_ssl_async_resume_t callback has run and has
1190 * returned a value other than
1191 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, since in that case
1192 * the asynchronous operation has already completed.
1193 *
1194 * This function may call mbedtls_ssl_get_async_operation_data()
1195 * to retrieve an operation context set by the start callback.
1196 *
1197 * \param ssl The SSL connection instance. It should not be
1198 * modified.
1199 */
1200 typedef void mbedtls_ssl_async_cancel_t(mbedtls_ssl_context *ssl);
1201 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1202
1203 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) && \
1204 !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
1205 #define MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN 48
1206 #if defined(MBEDTLS_MD_CAN_SHA256)
1207 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA256
1208 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 32
1209 #elif defined(MBEDTLS_MD_CAN_SHA384)
1210 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA384
1211 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 48
1212 #elif defined(MBEDTLS_MD_CAN_SHA1)
1213 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA1
1214 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 20
1215 #else
1216 /* This is already checked in check_config.h, but be sure. */
1217 #error "Bad configuration - need SHA-1, SHA-256 or SHA-512 enabled to compute digest of peer CRT."
1218 #endif
1219 #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED &&
1220 !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1221
1222 typedef struct {
1223 unsigned char client_application_traffic_secret_N[MBEDTLS_TLS1_3_MD_MAX_SIZE];
1224 unsigned char server_application_traffic_secret_N[MBEDTLS_TLS1_3_MD_MAX_SIZE];
1225 unsigned char exporter_master_secret[MBEDTLS_TLS1_3_MD_MAX_SIZE];
1226 unsigned char resumption_master_secret[MBEDTLS_TLS1_3_MD_MAX_SIZE];
1227 } mbedtls_ssl_tls13_application_secrets;
1228
1229 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1230
1231 #define MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH 255
1232 #define MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH 4
1233 /*
1234 * For code readability use a typedef for DTLS-SRTP profiles
1235 *
1236 * Use_srtp extension protection profiles values as defined in
1237 * http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
1238 *
1239 * Reminder: if this list is expanded mbedtls_ssl_check_srtp_profile_value
1240 * must be updated too.
1241 */
1242 #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80 ((uint16_t) 0x0001)
1243 #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32 ((uint16_t) 0x0002)
1244 #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80 ((uint16_t) 0x0005)
1245 #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32 ((uint16_t) 0x0006)
1246 /* This one is not iana defined, but for code readability. */
1247 #define MBEDTLS_TLS_SRTP_UNSET ((uint16_t) 0x0000)
1248
1249 typedef uint16_t mbedtls_ssl_srtp_profile;
1250
1251 typedef struct mbedtls_dtls_srtp_info_t {
1252 /*! The SRTP profile that was negotiated. */
1253 mbedtls_ssl_srtp_profile MBEDTLS_PRIVATE(chosen_dtls_srtp_profile);
1254 /*! The length of mki_value. */
1255 uint16_t MBEDTLS_PRIVATE(mki_len);
1256 /*! The mki_value used, with max size of 256 bytes. */
1257 unsigned char MBEDTLS_PRIVATE(mki_value)[MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH];
1258 }
1259 mbedtls_dtls_srtp_info;
1260
1261 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1262
1263 /** Human-friendly representation of the (D)TLS protocol version. */
1264 typedef enum {
1265 MBEDTLS_SSL_VERSION_UNKNOWN, /*!< Context not in use or version not yet negotiated. */
1266 MBEDTLS_SSL_VERSION_TLS1_2 = 0x0303, /*!< (D)TLS 1.2 */
1267 MBEDTLS_SSL_VERSION_TLS1_3 = 0x0304, /*!< (D)TLS 1.3 */
1268 } mbedtls_ssl_protocol_version;
1269
1270 /*
1271 * This structure is used for storing current session data.
1272 *
1273 * Note: when changing this definition, we need to check and update:
1274 * - in tests/suites/test_suite_ssl.function:
1275 * ssl_populate_session() and ssl_serialize_session_save_load()
1276 * - in library/ssl_tls.c:
1277 * mbedtls_ssl_session_init() and mbedtls_ssl_session_free()
1278 * mbedtls_ssl_session_save() and ssl_session_load()
1279 * ssl_session_copy()
1280 */
1281 struct mbedtls_ssl_session {
1282 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
1283 unsigned char MBEDTLS_PRIVATE(mfl_code); /*!< MaxFragmentLength negotiated by peer */
1284 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
1285
1286 /*!< RecordSizeLimit received from the peer */
1287 #if defined(MBEDTLS_SSL_RECORD_SIZE_LIMIT)
1288 uint16_t MBEDTLS_PRIVATE(record_size_limit);
1289 #endif /* MBEDTLS_SSL_RECORD_SIZE_LIMIT */
1290
1291 unsigned char MBEDTLS_PRIVATE(exported);
1292 uint8_t MBEDTLS_PRIVATE(endpoint); /*!< 0: client, 1: server */
1293
1294 /** TLS version negotiated in the session. Used if and when renegotiating
1295 * or resuming a session instead of the configured minor TLS version.
1296 */
1297 mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(tls_version);
1298
1299 #if defined(MBEDTLS_HAVE_TIME)
1300 mbedtls_time_t MBEDTLS_PRIVATE(start); /*!< start time of current session */
1301 #endif
1302 int MBEDTLS_PRIVATE(ciphersuite); /*!< chosen ciphersuite */
1303 size_t MBEDTLS_PRIVATE(id_len); /*!< session id length */
1304 unsigned char MBEDTLS_PRIVATE(id)[32]; /*!< session identifier */
1305 unsigned char MBEDTLS_PRIVATE(master)[48]; /*!< the master secret */
1306
1307 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1308 #if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
1309 mbedtls_x509_crt *MBEDTLS_PRIVATE(peer_cert); /*!< peer X.509 cert chain */
1310 #else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1311 /*! The digest of the peer's end-CRT. This must be kept to detect CRT
1312 * changes during renegotiation, mitigating the triple handshake attack. */
1313 unsigned char *MBEDTLS_PRIVATE(peer_cert_digest);
1314 size_t MBEDTLS_PRIVATE(peer_cert_digest_len);
1315 mbedtls_md_type_t MBEDTLS_PRIVATE(peer_cert_digest_type);
1316 #endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
1317 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1318 uint32_t MBEDTLS_PRIVATE(verify_result); /*!< verification result */
1319
1320 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
1321 unsigned char *MBEDTLS_PRIVATE(ticket); /*!< RFC 5077 session ticket */
1322 size_t MBEDTLS_PRIVATE(ticket_len); /*!< session ticket length */
1323 uint32_t MBEDTLS_PRIVATE(ticket_lifetime); /*!< ticket lifetime hint */
1324 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
1325
1326 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C) && \
1327 defined(MBEDTLS_HAVE_TIME)
1328 /*! When a ticket is created by a TLS server as part of an established TLS
1329 * session, the ticket creation time may need to be saved for the ticket
1330 * module to be able to check the ticket age when the ticket is used.
1331 * That's the purpose of this field.
1332 * Before creating a new ticket, an Mbed TLS server set this field with
1333 * its current time in milliseconds. This time may then be saved in the
1334 * session ticket data by the session ticket writing function and
1335 * recovered by the ticket parsing function later when the ticket is used.
1336 * The ticket module may then use this time to compute the ticket age and
1337 * determine if it has expired or not.
1338 * The Mbed TLS implementations of the session ticket writing and parsing
1339 * functions save and retrieve the ticket creation time as part of the
1340 * session ticket data. The session ticket parsing function relies on
1341 * the mbedtls_ssl_session_get_ticket_creation_time() API to get the
1342 * ticket creation time from the session ticket data.
1343 */
1344 mbedtls_ms_time_t MBEDTLS_PRIVATE(ticket_creation_time);
1345 #endif
1346
1347 #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS)
1348 uint32_t MBEDTLS_PRIVATE(ticket_age_add); /*!< Randomly generated value used to obscure the age of the ticket */
1349 uint8_t MBEDTLS_PRIVATE(ticket_flags); /*!< Ticket flags */
1350 uint8_t MBEDTLS_PRIVATE(resumption_key_len); /*!< resumption_key length */
1351 unsigned char MBEDTLS_PRIVATE(resumption_key)[MBEDTLS_SSL_TLS1_3_TICKET_RESUMPTION_KEY_LEN];
1352
1353 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) && defined(MBEDTLS_SSL_CLI_C)
1354 char *MBEDTLS_PRIVATE(hostname); /*!< host name binded with tickets */
1355 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION && MBEDTLS_SSL_CLI_C */
1356
1357 #if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_ALPN) && defined(MBEDTLS_SSL_SRV_C)
1358 char *ticket_alpn; /*!< ALPN negotiated in the session
1359 during which the ticket was generated. */
1360 #endif
1361
1362 #if defined(MBEDTLS_HAVE_TIME) && defined(MBEDTLS_SSL_CLI_C)
1363 /*! Time in milliseconds when the last ticket was received. */
1364 mbedtls_ms_time_t MBEDTLS_PRIVATE(ticket_reception_time);
1365 #endif
1366 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */
1367
1368 #if defined(MBEDTLS_SSL_EARLY_DATA)
1369 uint32_t MBEDTLS_PRIVATE(max_early_data_size); /*!< maximum amount of early data in tickets */
1370 #endif
1371
1372 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1373 int MBEDTLS_PRIVATE(encrypt_then_mac); /*!< flag for EtM activation */
1374 #endif
1375
1376 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1377 mbedtls_ssl_tls13_application_secrets MBEDTLS_PRIVATE(app_secrets);
1378 #endif
1379 };
1380
1381 /*
1382 * Identifiers for PRFs used in various versions of TLS.
1383 */
1384 typedef enum {
1385 MBEDTLS_SSL_TLS_PRF_NONE,
1386 MBEDTLS_SSL_TLS_PRF_SHA384,
1387 MBEDTLS_SSL_TLS_PRF_SHA256,
1388 MBEDTLS_SSL_HKDF_EXPAND_SHA384,
1389 MBEDTLS_SSL_HKDF_EXPAND_SHA256
1390 }
1391 mbedtls_tls_prf_types;
1392
1393 typedef enum {
1394 MBEDTLS_SSL_KEY_EXPORT_TLS12_MASTER_SECRET = 0,
1395 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1396 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_EARLY_SECRET,
1397 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_EARLY_EXPORTER_SECRET,
1398 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_HANDSHAKE_TRAFFIC_SECRET,
1399 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_SERVER_HANDSHAKE_TRAFFIC_SECRET,
1400 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_APPLICATION_TRAFFIC_SECRET,
1401 MBEDTLS_SSL_KEY_EXPORT_TLS1_3_SERVER_APPLICATION_TRAFFIC_SECRET,
1402 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1403 } mbedtls_ssl_key_export_type;
1404
1405 /**
1406 * \brief Callback type: Export key alongside random values for
1407 * session identification, and PRF for
1408 * implementation of TLS key exporters.
1409 *
1410 * \param p_expkey Context for the callback.
1411 * \param type The type of the key that is being exported.
1412 * \param secret The address of the buffer holding the secret
1413 * that's being exporterd.
1414 * \param secret_len The length of \p secret in bytes.
1415 * \param client_random The client random bytes.
1416 * \param server_random The server random bytes.
1417 * \param tls_prf_type The identifier for the PRF used in the handshake
1418 * to which the key belongs.
1419 */
1420 typedef void mbedtls_ssl_export_keys_t(void *p_expkey,
1421 mbedtls_ssl_key_export_type type,
1422 const unsigned char *secret,
1423 size_t secret_len,
1424 const unsigned char client_random[32],
1425 const unsigned char server_random[32],
1426 mbedtls_tls_prf_types tls_prf_type);
1427
1428 #if defined(MBEDTLS_SSL_SRV_C)
1429 /**
1430 * \brief Callback type: generic handshake callback
1431 *
1432 * \note Callbacks may use user_data funcs to set/get app user data.
1433 * See \c mbedtls_ssl_get_user_data_p()
1434 * \c mbedtls_ssl_get_user_data_n()
1435 * \c mbedtls_ssl_conf_get_user_data_p()
1436 * \c mbedtls_ssl_conf_get_user_data_n()
1437 *
1438 * \param ssl \c mbedtls_ssl_context on which the callback is run
1439 *
1440 * \return The return value of the callback is 0 if successful,
1441 * or a specific MBEDTLS_ERR_XXX code, which will cause
1442 * the handshake to be aborted.
1443 */
1444 typedef int (*mbedtls_ssl_hs_cb_t)(mbedtls_ssl_context *ssl);
1445 #endif
1446
1447 /* A type for storing user data in a library structure.
1448 *
1449 * The representation of type may change in future versions of the library.
1450 * Only the behaviors guaranteed by documented accessor functions are
1451 * guaranteed to remain stable.
1452 */
1453 typedef union {
1454 uintptr_t n; /* typically a handle to an associated object */
1455 void *p; /* typically a pointer to extra data */
1456 } mbedtls_ssl_user_data_t;
1457
1458 /**
1459 * SSL/TLS configuration to be shared between mbedtls_ssl_context structures.
1460 */
1461 struct mbedtls_ssl_config {
1462 /* Group items mostly by size. This helps to reduce memory wasted to
1463 * padding. It also helps to keep smaller fields early in the structure,
1464 * so that elements tend to be in the 128-element direct access window
1465 * on Arm Thumb, which reduces the code size. */
1466
1467 mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(max_tls_version); /*!< max. TLS version used */
1468 mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(min_tls_version); /*!< min. TLS version used */
1469
1470 /*
1471 * Flags (could be bit-fields to save RAM, but separate bytes make
1472 * the code smaller on architectures with an instruction for direct
1473 * byte access).
1474 */
1475
1476 uint8_t MBEDTLS_PRIVATE(endpoint); /*!< 0: client, 1: server */
1477 uint8_t MBEDTLS_PRIVATE(transport); /*!< 0: stream (TLS), 1: datagram (DTLS) */
1478 uint8_t MBEDTLS_PRIVATE(authmode); /*!< MBEDTLS_SSL_VERIFY_XXX */
1479 /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE */
1480 uint8_t MBEDTLS_PRIVATE(allow_legacy_renegotiation); /*!< MBEDTLS_LEGACY_XXX */
1481 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
1482 uint8_t MBEDTLS_PRIVATE(mfl_code); /*!< desired fragment length indicator
1483 (MBEDTLS_SSL_MAX_FRAG_LEN_XXX) */
1484 #endif
1485 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1486 uint8_t MBEDTLS_PRIVATE(encrypt_then_mac); /*!< negotiate encrypt-then-mac? */
1487 #endif
1488 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
1489 uint8_t MBEDTLS_PRIVATE(extended_ms); /*!< negotiate extended master secret? */
1490 #endif
1491 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1492 uint8_t MBEDTLS_PRIVATE(anti_replay); /*!< detect and prevent replay? */
1493 #endif
1494 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1495 uint8_t MBEDTLS_PRIVATE(disable_renegotiation); /*!< disable renegotiation? */
1496 #endif
1497 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && \
1498 defined(MBEDTLS_SSL_CLI_C)
1499 /** Encodes two booleans, one stating whether TLS 1.2 session tickets are
1500 * enabled or not, the other one whether the handling of TLS 1.3
1501 * NewSessionTicket messages is enabled or not. They are respectively set
1502 * by mbedtls_ssl_conf_session_tickets() and
1503 * mbedtls_ssl_conf_tls13_enable_signal_new_session_tickets().
1504 */
1505 uint8_t MBEDTLS_PRIVATE(session_tickets); /*!< use session tickets? */
1506 #endif
1507
1508 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && \
1509 defined(MBEDTLS_SSL_SRV_C) && \
1510 defined(MBEDTLS_SSL_PROTO_TLS1_3)
1511 uint16_t MBEDTLS_PRIVATE(new_session_tickets_count); /*!< number of NewSessionTicket */
1512 #endif
1513
1514 #if defined(MBEDTLS_SSL_SRV_C)
1515 uint8_t MBEDTLS_PRIVATE(cert_req_ca_list); /*!< enable sending CA list in
1516 Certificate Request messages? */
1517 uint8_t MBEDTLS_PRIVATE(respect_cli_pref); /*!< pick the ciphersuite according to
1518 the client's preferences rather
1519 than ours? */
1520 #endif
1521 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1522 uint8_t MBEDTLS_PRIVATE(ignore_unexpected_cid); /*!< Should DTLS record with
1523 * unexpected CID
1524 * lead to failure? */
1525 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1526 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1527 uint8_t MBEDTLS_PRIVATE(dtls_srtp_mki_support); /* support having mki_value
1528 in the use_srtp extension? */
1529 #endif
1530
1531 /*
1532 * Pointers
1533 */
1534
1535 /** Allowed ciphersuites for (D)TLS 1.2 (0-terminated) */
1536 const int *MBEDTLS_PRIVATE(ciphersuite_list);
1537
1538 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1539 /** Allowed TLS 1.3 key exchange modes. */
1540 int MBEDTLS_PRIVATE(tls13_kex_modes);
1541 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1542
1543 /** Callback for printing debug output */
1544 void(*MBEDTLS_PRIVATE(f_dbg))(void *, int, const char *, int, const char *);
1545 void *MBEDTLS_PRIVATE(p_dbg); /*!< context for the debug function */
1546
1547 /** Callback for getting (pseudo-)random numbers */
1548 int(*MBEDTLS_PRIVATE(f_rng))(void *, unsigned char *, size_t);
1549 void *MBEDTLS_PRIVATE(p_rng); /*!< context for the RNG function */
1550
1551 /** Callback to retrieve a session from the cache */
1552 mbedtls_ssl_cache_get_t *MBEDTLS_PRIVATE(f_get_cache);
1553 /** Callback to store a session into the cache */
1554 mbedtls_ssl_cache_set_t *MBEDTLS_PRIVATE(f_set_cache);
1555 void *MBEDTLS_PRIVATE(p_cache); /*!< context for cache callbacks */
1556
1557 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
1558 /** Callback for setting cert according to SNI extension */
1559 int(*MBEDTLS_PRIVATE(f_sni))(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
1560 void *MBEDTLS_PRIVATE(p_sni); /*!< context for SNI callback */
1561 #endif
1562
1563 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1564 /** Callback to customize X.509 certificate chain verification */
1565 int(*MBEDTLS_PRIVATE(f_vrfy))(void *, mbedtls_x509_crt *, int, uint32_t *);
1566 void *MBEDTLS_PRIVATE(p_vrfy); /*!< context for X.509 verify calllback */
1567 #endif
1568
1569 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED)
1570 #if defined(MBEDTLS_SSL_SRV_C)
1571 /** Callback to retrieve PSK key from identity */
1572 int(*MBEDTLS_PRIVATE(f_psk))(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
1573 void *MBEDTLS_PRIVATE(p_psk); /*!< context for PSK callback */
1574 #endif
1575 #endif
1576
1577 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1578 /** Callback to create & write a cookie for ClientHello verification */
1579 int(*MBEDTLS_PRIVATE(f_cookie_write))(void *, unsigned char **, unsigned char *,
1580 const unsigned char *, size_t);
1581 /** Callback to verify validity of a ClientHello cookie */
1582 int(*MBEDTLS_PRIVATE(f_cookie_check))(void *, const unsigned char *, size_t,
1583 const unsigned char *, size_t);
1584 void *MBEDTLS_PRIVATE(p_cookie); /*!< context for the cookie callbacks */
1585 #endif
1586
1587 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
1588 /** Callback to create & write a session ticket */
1589 int(*MBEDTLS_PRIVATE(f_ticket_write))(void *, const mbedtls_ssl_session *,
1590 unsigned char *, const unsigned char *, size_t *,
1591 uint32_t *);
1592 /** Callback to parse a session ticket into a session structure */
1593 int(*MBEDTLS_PRIVATE(f_ticket_parse))(void *, mbedtls_ssl_session *, unsigned char *, size_t);
1594 void *MBEDTLS_PRIVATE(p_ticket); /*!< context for the ticket callbacks */
1595 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
1596 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1597 size_t MBEDTLS_PRIVATE(cid_len); /*!< The length of CIDs for incoming DTLS records. */
1598 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1599
1600 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1601 const mbedtls_x509_crt_profile *MBEDTLS_PRIVATE(cert_profile); /*!< verification profile */
1602 mbedtls_ssl_key_cert *MBEDTLS_PRIVATE(key_cert); /*!< own certificate/key pair(s) */
1603 mbedtls_x509_crt *MBEDTLS_PRIVATE(ca_chain); /*!< trusted CAs */
1604 mbedtls_x509_crl *MBEDTLS_PRIVATE(ca_crl); /*!< trusted CAs CRLs */
1605 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
1606 mbedtls_x509_crt_ca_cb_t MBEDTLS_PRIVATE(f_ca_cb);
1607 void *MBEDTLS_PRIVATE(p_ca_cb);
1608 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
1609 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1610
1611 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
1612 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1613 mbedtls_ssl_async_sign_t *MBEDTLS_PRIVATE(f_async_sign_start); /*!< start asynchronous signature operation */
1614 mbedtls_ssl_async_decrypt_t *MBEDTLS_PRIVATE(f_async_decrypt_start); /*!< start asynchronous decryption operation */
1615 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1616 mbedtls_ssl_async_resume_t *MBEDTLS_PRIVATE(f_async_resume); /*!< resume asynchronous operation */
1617 mbedtls_ssl_async_cancel_t *MBEDTLS_PRIVATE(f_async_cancel); /*!< cancel asynchronous operation */
1618 void *MBEDTLS_PRIVATE(p_async_config_data); /*!< Configuration data set by mbedtls_ssl_conf_async_private_cb(). */
1619 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1620
1621 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
1622
1623 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
1624 const int *MBEDTLS_PRIVATE(sig_hashes); /*!< allowed signature hashes */
1625 #endif
1626 const uint16_t *MBEDTLS_PRIVATE(sig_algs); /*!< allowed signature algorithms */
1627 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
1628
1629 #if defined(MBEDTLS_ECP_C) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1630 const mbedtls_ecp_group_id *MBEDTLS_PRIVATE(curve_list); /*!< allowed curves */
1631 #endif
1632
1633 const uint16_t *MBEDTLS_PRIVATE(group_list); /*!< allowed IANA NamedGroups */
1634
1635 #if defined(MBEDTLS_DHM_C)
1636 mbedtls_mpi MBEDTLS_PRIVATE(dhm_P); /*!< prime modulus for DHM */
1637 mbedtls_mpi MBEDTLS_PRIVATE(dhm_G); /*!< generator for DHM */
1638 #endif
1639
1640 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED)
1641
1642 #if defined(MBEDTLS_USE_PSA_CRYPTO)
1643 mbedtls_svc_key_id_t MBEDTLS_PRIVATE(psk_opaque); /*!< PSA key slot holding opaque PSK. This field
1644 * should only be set via
1645 * mbedtls_ssl_conf_psk_opaque().
1646 * If either no PSK or a raw PSK have been
1647 * configured, this has value \c 0.
1648 */
1649 #endif /* MBEDTLS_USE_PSA_CRYPTO */
1650 unsigned char *MBEDTLS_PRIVATE(psk); /*!< The raw pre-shared key. This field should
1651 * only be set via mbedtls_ssl_conf_psk().
1652 * If either no PSK or an opaque PSK
1653 * have been configured, this has value NULL. */
1654 size_t MBEDTLS_PRIVATE(psk_len); /*!< The length of the raw pre-shared key.
1655 * This field should only be set via
1656 * mbedtls_ssl_conf_psk().
1657 * Its value is non-zero if and only if
1658 * \c psk is not \c NULL. */
1659
1660 unsigned char *MBEDTLS_PRIVATE(psk_identity); /*!< The PSK identity for PSK negotiation.
1661 * This field should only be set via
1662 * mbedtls_ssl_conf_psk().
1663 * This is set if and only if either
1664 * \c psk or \c psk_opaque are set. */
1665 size_t MBEDTLS_PRIVATE(psk_identity_len);/*!< The length of PSK identity.
1666 * This field should only be set via
1667 * mbedtls_ssl_conf_psk().
1668 * Its value is non-zero if and only if
1669 * \c psk is not \c NULL or \c psk_opaque
1670 * is not \c 0. */
1671 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED */
1672
1673 #if defined(MBEDTLS_SSL_EARLY_DATA)
1674 int MBEDTLS_PRIVATE(early_data_enabled); /*!< Early data enablement:
1675 * - MBEDTLS_SSL_EARLY_DATA_DISABLED,
1676 * - MBEDTLS_SSL_EARLY_DATA_ENABLED */
1677
1678 #if defined(MBEDTLS_SSL_SRV_C)
1679 /* The maximum amount of 0-RTT data. RFC 8446 section 4.6.1 */
1680 uint32_t MBEDTLS_PRIVATE(max_early_data_size);
1681 #endif /* MBEDTLS_SSL_SRV_C */
1682
1683 #endif /* MBEDTLS_SSL_EARLY_DATA */
1684
1685 #if defined(MBEDTLS_SSL_ALPN)
1686 const char **MBEDTLS_PRIVATE(alpn_list); /*!< ordered list of protocols */
1687 #endif
1688
1689 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1690 /*! ordered list of supported srtp profile */
1691 const mbedtls_ssl_srtp_profile *MBEDTLS_PRIVATE(dtls_srtp_profile_list);
1692 /*! number of supported profiles */
1693 size_t MBEDTLS_PRIVATE(dtls_srtp_profile_list_len);
1694 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1695
1696 /*
1697 * Numerical settings (int)
1698 */
1699
1700 uint32_t MBEDTLS_PRIVATE(read_timeout); /*!< timeout for mbedtls_ssl_read (ms) */
1701
1702 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1703 uint32_t MBEDTLS_PRIVATE(hs_timeout_min); /*!< initial value of the handshake
1704 retransmission timeout (ms) */
1705 uint32_t MBEDTLS_PRIVATE(hs_timeout_max); /*!< maximum value of the handshake
1706 retransmission timeout (ms) */
1707 #endif
1708
1709 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1710 int MBEDTLS_PRIVATE(renego_max_records); /*!< grace period for renegotiation */
1711 unsigned char MBEDTLS_PRIVATE(renego_period)[8]; /*!< value of the record counters
1712 that triggers renegotiation */
1713 #endif
1714
1715 unsigned int MBEDTLS_PRIVATE(badmac_limit); /*!< limit of records with a bad MAC */
1716
1717 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
1718 unsigned int MBEDTLS_PRIVATE(dhm_min_bitlen); /*!< min. bit length of the DHM prime */
1719 #endif
1720
1721 /** User data pointer or handle.
1722 *
1723 * The library sets this to \p 0 when creating a context and does not
1724 * access it afterwards.
1725 */
1726 mbedtls_ssl_user_data_t MBEDTLS_PRIVATE(user_data);
1727
1728 #if defined(MBEDTLS_SSL_SRV_C)
1729 mbedtls_ssl_hs_cb_t MBEDTLS_PRIVATE(f_cert_cb); /*!< certificate selection callback */
1730 #endif /* MBEDTLS_SSL_SRV_C */
1731
1732 #if defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED)
1733 const mbedtls_x509_crt *MBEDTLS_PRIVATE(dn_hints);/*!< acceptable client cert issuers */
1734 #endif
1735 };
1736
1737 struct mbedtls_ssl_context {
1738 const mbedtls_ssl_config *MBEDTLS_PRIVATE(conf); /*!< configuration information */
1739
1740 /*
1741 * Miscellaneous
1742 */
1743 int MBEDTLS_PRIVATE(state); /*!< SSL handshake: current state */
1744 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1745 int MBEDTLS_PRIVATE(renego_status); /*!< Initial, in progress, pending? */
1746 int MBEDTLS_PRIVATE(renego_records_seen); /*!< Records since renego request, or with DTLS,
1747 number of retransmissions of request if
1748 renego_max_records is < 0 */
1749 #endif /* MBEDTLS_SSL_RENEGOTIATION */
1750
1751 /**
1752 * Maximum TLS version to be negotiated, then negotiated TLS version.
1753 *
1754 * It is initialized as the configured maximum TLS version to be
1755 * negotiated by mbedtls_ssl_setup().
1756 *
1757 * When renegotiating or resuming a session, it is overwritten in the
1758 * ClientHello writing preparation stage with the previously negotiated
1759 * TLS version.
1760 *
1761 * On client side, it is updated to the TLS version selected by the server
1762 * for the handshake when the ServerHello is received.
1763 *
1764 * On server side, it is updated to the TLS version the server selects for
1765 * the handshake when the ClientHello is received.
1766 */
1767 mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(tls_version);
1768
1769 #if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C)
1770 /**
1771 * State of the negotiation and transfer of early data. Reset to
1772 * MBEDTLS_SSL_EARLY_DATA_STATE_IDLE when the context is reset.
1773 */
1774 int MBEDTLS_PRIVATE(early_data_state);
1775 #endif
1776
1777 /** Multipurpose field.
1778 *
1779 * - DTLS: records with a bad MAC received.
1780 * - TLS: accumulated length of handshake fragments (up to \c in_hslen).
1781 *
1782 * This field is multipurpose in order to preserve the ABI in the
1783 * Mbed TLS 3.6 LTS branch. Until 3.6.2, it was only used in DTLS
1784 * and called `badmac_seen`.
1785 */
1786 unsigned MBEDTLS_PRIVATE(badmac_seen_or_in_hsfraglen);
1787
1788 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1789 /** Callback to customize X.509 certificate chain verification */
1790 int(*MBEDTLS_PRIVATE(f_vrfy))(void *, mbedtls_x509_crt *, int, uint32_t *);
1791 void *MBEDTLS_PRIVATE(p_vrfy); /*!< context for X.509 verify callback */
1792 #endif
1793
1794 mbedtls_ssl_send_t *MBEDTLS_PRIVATE(f_send); /*!< Callback for network send */
1795 mbedtls_ssl_recv_t *MBEDTLS_PRIVATE(f_recv); /*!< Callback for network receive */
1796 mbedtls_ssl_recv_timeout_t *MBEDTLS_PRIVATE(f_recv_timeout);
1797 /*!< Callback for network receive with timeout */
1798
1799 void *MBEDTLS_PRIVATE(p_bio); /*!< context for I/O operations */
1800
1801 /*
1802 * Session layer
1803 */
1804 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_in); /*!< current session data (in) */
1805 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_out); /*!< current session data (out) */
1806 mbedtls_ssl_session *MBEDTLS_PRIVATE(session); /*!< negotiated session data */
1807 mbedtls_ssl_session *MBEDTLS_PRIVATE(session_negotiate); /*!< session data in negotiation */
1808
1809 mbedtls_ssl_handshake_params *MBEDTLS_PRIVATE(handshake); /*!< params required only during
1810 the handshake process */
1811
1812 /*
1813 * Record layer transformations
1814 */
1815 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_in); /*!< current transform params (in)
1816 * This is always a reference,
1817 * never an owning pointer. */
1818 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_out); /*!< current transform params (out)
1819 * This is always a reference,
1820 * never an owning pointer. */
1821 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform); /*!< negotiated transform params
1822 * This pointer owns the transform
1823 * it references. */
1824 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
1825 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_negotiate); /*!< transform params in negotiation
1826 * This pointer owns the transform
1827 * it references. */
1828 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
1829
1830 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1831 /*! The application data transform in TLS 1.3.
1832 * This pointer owns the transform it references. */
1833 mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_application);
1834 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1835
1836 /*
1837 * Timers
1838 */
1839 void *MBEDTLS_PRIVATE(p_timer); /*!< context for the timer callbacks */
1840
1841 mbedtls_ssl_set_timer_t *MBEDTLS_PRIVATE(f_set_timer); /*!< set timer callback */
1842 mbedtls_ssl_get_timer_t *MBEDTLS_PRIVATE(f_get_timer); /*!< get timer callback */
1843
1844 /*
1845 * Record layer (incoming data)
1846 */
1847 unsigned char *MBEDTLS_PRIVATE(in_buf); /*!< input buffer */
1848 unsigned char *MBEDTLS_PRIVATE(in_ctr); /*!< 64-bit incoming message counter
1849 TLS: maintained by us
1850 DTLS: read from peer */
1851 unsigned char *MBEDTLS_PRIVATE(in_hdr); /*!< start of record header */
1852 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1853 unsigned char *MBEDTLS_PRIVATE(in_cid); /*!< The start of the CID;
1854 * (the end is marked by in_len). */
1855 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1856 unsigned char *MBEDTLS_PRIVATE(in_len); /*!< two-bytes message length field */
1857 unsigned char *MBEDTLS_PRIVATE(in_iv); /*!< ivlen-byte IV */
1858 unsigned char *MBEDTLS_PRIVATE(in_msg); /*!< message contents (in_iv+ivlen) */
1859 unsigned char *MBEDTLS_PRIVATE(in_offt); /*!< read offset in application data */
1860
1861 int MBEDTLS_PRIVATE(in_msgtype); /*!< record header: message type */
1862 size_t MBEDTLS_PRIVATE(in_msglen); /*!< record header: message length */
1863 size_t MBEDTLS_PRIVATE(in_left); /*!< amount of data read so far */
1864 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1865 size_t MBEDTLS_PRIVATE(in_buf_len); /*!< length of input buffer */
1866 #endif
1867 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1868 uint16_t MBEDTLS_PRIVATE(in_epoch); /*!< DTLS epoch for incoming records */
1869 size_t MBEDTLS_PRIVATE(next_record_offset); /*!< offset of the next record in datagram
1870 (equal to in_left if none) */
1871 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1872 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1873 uint64_t MBEDTLS_PRIVATE(in_window_top); /*!< last validated record seq_num */
1874 uint64_t MBEDTLS_PRIVATE(in_window); /*!< bitmask for replay detection */
1875 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
1876
1877 size_t MBEDTLS_PRIVATE(in_hslen); /*!< current handshake message length,
1878 including the handshake header */
1879 int MBEDTLS_PRIVATE(nb_zero); /*!< # of 0-length encrypted messages */
1880
1881 int MBEDTLS_PRIVATE(keep_current_message); /*!< drop or reuse current message
1882 on next call to record layer? */
1883
1884 /* The following three variables indicate if and, if yes,
1885 * what kind of alert is pending to be sent.
1886 */
1887 unsigned char MBEDTLS_PRIVATE(send_alert); /*!< Determines if a fatal alert
1888 should be sent. Values:
1889 - \c 0 , no alert is to be sent.
1890 - \c 1 , alert is to be sent. */
1891 unsigned char MBEDTLS_PRIVATE(alert_type); /*!< Type of alert if send_alert
1892 != 0 */
1893 int MBEDTLS_PRIVATE(alert_reason); /*!< The error code to be returned
1894 to the user once the fatal alert
1895 has been sent. */
1896
1897 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1898 uint8_t MBEDTLS_PRIVATE(disable_datagram_packing); /*!< Disable packing multiple records
1899 * within a single datagram. */
1900 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1901
1902 #if defined(MBEDTLS_SSL_EARLY_DATA)
1903 #if defined(MBEDTLS_SSL_SRV_C)
1904 /*
1905 * One of:
1906 * MBEDTLS_SSL_EARLY_DATA_NO_DISCARD
1907 * MBEDTLS_SSL_EARLY_DATA_TRY_TO_DEPROTECT_AND_DISCARD
1908 * MBEDTLS_SSL_EARLY_DATA_DISCARD
1909 */
1910 uint8_t MBEDTLS_PRIVATE(discard_early_data_record);
1911 #endif
1912 uint32_t MBEDTLS_PRIVATE(total_early_data_size); /*!< Number of received/written early data bytes */
1913 #endif /* MBEDTLS_SSL_EARLY_DATA */
1914
1915 /*
1916 * Record layer (outgoing data)
1917 */
1918 unsigned char *MBEDTLS_PRIVATE(out_buf); /*!< output buffer */
1919 unsigned char *MBEDTLS_PRIVATE(out_ctr); /*!< 64-bit outgoing message counter */
1920 unsigned char *MBEDTLS_PRIVATE(out_hdr); /*!< start of record header */
1921 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1922 unsigned char *MBEDTLS_PRIVATE(out_cid); /*!< The start of the CID;
1923 * (the end is marked by in_len). */
1924 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1925 unsigned char *MBEDTLS_PRIVATE(out_len); /*!< two-bytes message length field */
1926 unsigned char *MBEDTLS_PRIVATE(out_iv); /*!< ivlen-byte IV */
1927 unsigned char *MBEDTLS_PRIVATE(out_msg); /*!< message contents (out_iv+ivlen) */
1928
1929 int MBEDTLS_PRIVATE(out_msgtype); /*!< record header: message type */
1930 size_t MBEDTLS_PRIVATE(out_msglen); /*!< record header: message length */
1931 size_t MBEDTLS_PRIVATE(out_left); /*!< amount of data not yet written */
1932 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1933 size_t MBEDTLS_PRIVATE(out_buf_len); /*!< length of output buffer */
1934 #endif
1935
1936 unsigned char MBEDTLS_PRIVATE(cur_out_ctr)[MBEDTLS_SSL_SEQUENCE_NUMBER_LEN]; /*!< Outgoing record sequence number. */
1937
1938 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1939 uint16_t MBEDTLS_PRIVATE(mtu); /*!< path mtu, used to fragment outgoing messages */
1940 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1941
1942 /*
1943 * User settings
1944 */
1945 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1946 /** Expected peer CN for verification.
1947 *
1948 * Also used on clients for SNI,
1949 * and for TLS 1.3 session resumption using tickets.
1950 *
1951 * The value of this field can be:
1952 * - \p NULL in a newly initialized or reset context.
1953 * - A heap-allocated copy of the last value passed to
1954 * mbedtls_ssl_set_hostname(), if the last call had a non-null
1955 * \p hostname argument.
1956 * - A special value to indicate that mbedtls_ssl_set_hostname()
1957 * was called with \p NULL (as opposed to never having been called).
1958 * See `mbedtls_ssl_get_hostname_pointer()` in `ssl_tls.c`.
1959 *
1960 * If this field contains the value \p NULL and the configuration option
1961 * #MBEDTLS_SSL_CLI_ALLOW_WEAK_CERTIFICATE_VERIFICATION_WITHOUT_HOSTNAME
1962 * is unset, on a TLS client, attempting to verify a server certificate
1963 * results in the error
1964 * #MBEDTLS_ERR_SSL_CERTIFICATE_VERIFICATION_WITHOUT_HOSTNAME.
1965 *
1966 * If this field contains the special value described above, or if
1967 * the value is \p NULL and the configuration option
1968 * #MBEDTLS_SSL_CLI_ALLOW_WEAK_CERTIFICATE_VERIFICATION_WITHOUT_HOSTNAME
1969 * is set, then the peer name verification is skipped, which may be
1970 * insecure, especially on a client. Furthermore, on a client, the
1971 * server_name extension is not sent, and the server name is ignored
1972 * in TLS 1.3 session resumption using tickets.
1973 */
1974 char *MBEDTLS_PRIVATE(hostname);
1975 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1976
1977 #if defined(MBEDTLS_SSL_ALPN)
1978 const char *MBEDTLS_PRIVATE(alpn_chosen); /*!< negotiated protocol */
1979 #endif /* MBEDTLS_SSL_ALPN */
1980
1981 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1982 /*
1983 * use_srtp extension
1984 */
1985 mbedtls_dtls_srtp_info MBEDTLS_PRIVATE(dtls_srtp_info);
1986 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1987
1988 /*
1989 * Information for DTLS hello verify
1990 */
1991 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1992 unsigned char *MBEDTLS_PRIVATE(cli_id); /*!< transport-level ID of the client */
1993 size_t MBEDTLS_PRIVATE(cli_id_len); /*!< length of cli_id */
1994 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
1995
1996 /*
1997 * Secure renegotiation
1998 */
1999 /* needed to know when to send extension on server */
2000 int MBEDTLS_PRIVATE(secure_renegotiation); /*!< does peer support legacy or
2001 secure renegotiation */
2002 #if defined(MBEDTLS_SSL_RENEGOTIATION)
2003 size_t MBEDTLS_PRIVATE(verify_data_len); /*!< length of verify data stored */
2004 char MBEDTLS_PRIVATE(own_verify_data)[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
2005 char MBEDTLS_PRIVATE(peer_verify_data)[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
2006 #endif /* MBEDTLS_SSL_RENEGOTIATION */
2007
2008 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
2009 /* CID configuration to use in subsequent handshakes. */
2010
2011 /*! The next incoming CID, chosen by the user and applying to
2012 * all subsequent handshakes. This may be different from the
2013 * CID currently used in case the user has re-configured the CID
2014 * after an initial handshake. */
2015 unsigned char MBEDTLS_PRIVATE(own_cid)[MBEDTLS_SSL_CID_IN_LEN_MAX];
2016 uint8_t MBEDTLS_PRIVATE(own_cid_len); /*!< The length of \c own_cid. */
2017 uint8_t MBEDTLS_PRIVATE(negotiate_cid); /*!< This indicates whether the CID extension should
2018 * be negotiated in the next handshake or not.
2019 * Possible values are #MBEDTLS_SSL_CID_ENABLED
2020 * and #MBEDTLS_SSL_CID_DISABLED. */
2021 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
2022
2023 /** Callback to export key block and master secret */
2024 mbedtls_ssl_export_keys_t *MBEDTLS_PRIVATE(f_export_keys);
2025 void *MBEDTLS_PRIVATE(p_export_keys); /*!< context for key export callback */
2026
2027 /** User data pointer or handle.
2028 *
2029 * The library sets this to \p 0 when creating a context and does not
2030 * access it afterwards.
2031 *
2032 * \warning Serializing and restoring an SSL context with
2033 * mbedtls_ssl_context_save() and mbedtls_ssl_context_load()
2034 * does not currently restore the user data.
2035 */
2036 mbedtls_ssl_user_data_t MBEDTLS_PRIVATE(user_data);
2037 };
2038
2039 /**
2040 * \brief Return the name of the ciphersuite associated with the
2041 * given ID
2042 *
2043 * \param ciphersuite_id SSL ciphersuite ID
2044 *
2045 * \return a string containing the ciphersuite name
2046 */
2047 const char *mbedtls_ssl_get_ciphersuite_name(const int ciphersuite_id);
2048
2049 /**
2050 * \brief Return the ID of the ciphersuite associated with the
2051 * given name
2052 *
2053 * \param ciphersuite_name SSL ciphersuite name
2054 *
2055 * \return the ID with the ciphersuite or 0 if not found
2056 */
2057 int mbedtls_ssl_get_ciphersuite_id(const char *ciphersuite_name);
2058
2059 /**
2060 * \brief Initialize an SSL context
2061 * Just makes the context ready for mbedtls_ssl_setup() or
2062 * mbedtls_ssl_free()
2063 *
2064 * \param ssl SSL context
2065 */
2066 void mbedtls_ssl_init(mbedtls_ssl_context *ssl);
2067
2068 /**
2069 * \brief Set up an SSL context for use
2070 *
2071 * \note No copy of the configuration context is made, it can be
2072 * shared by many mbedtls_ssl_context structures.
2073 *
2074 * \warning The conf structure will be accessed during the session.
2075 * It must not be modified or freed as long as the session
2076 * is active.
2077 *
2078 * \warning This function must be called exactly once per context.
2079 * Calling mbedtls_ssl_setup again is not supported, even
2080 * if no session is active.
2081 *
2082 * \warning After setting up a client context, if certificate-based
2083 * authentication is enabled, you should call
2084 * mbedtls_ssl_set_hostname() to specifiy the expected
2085 * name of the server. Without this, in most scenarios,
2086 * the TLS connection is insecure. See
2087 * #MBEDTLS_ERR_SSL_CERTIFICATE_VERIFICATION_WITHOUT_HOSTNAME
2088 * for more information.
2089 *
2090 * \note If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto
2091 * subsystem must have been initialized by calling
2092 * psa_crypto_init() before calling this function.
2093 *
2094 * \param ssl SSL context
2095 * \param conf SSL configuration to use
2096 *
2097 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED if
2098 * memory allocation failed
2099 */
2100 int mbedtls_ssl_setup(mbedtls_ssl_context *ssl,
2101 const mbedtls_ssl_config *conf);
2102
2103 /**
2104 * \brief Reset an already initialized SSL context for re-use
2105 * while retaining application-set variables, function
2106 * pointers and data.
2107 *
2108 * \param ssl SSL context
2109 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED or
2110 MBEDTLS_ERR_SSL_HW_ACCEL_FAILED
2111 */
2112 int mbedtls_ssl_session_reset(mbedtls_ssl_context *ssl);
2113
2114 /**
2115 * \brief Set the current endpoint type
2116 *
2117 * \param conf SSL configuration
2118 * \param endpoint must be MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
2119 */
2120 void mbedtls_ssl_conf_endpoint(mbedtls_ssl_config *conf, int endpoint);
2121
2122 /**
2123 * \brief Get the current endpoint type
2124 *
2125 * \param conf SSL configuration
2126 *
2127 * \return Endpoint type, either MBEDTLS_SSL_IS_CLIENT
2128 * or MBEDTLS_SSL_IS_SERVER
2129 */
mbedtls_ssl_conf_get_endpoint(const mbedtls_ssl_config * conf)2130 static inline int mbedtls_ssl_conf_get_endpoint(const mbedtls_ssl_config *conf)
2131 {
2132 return conf->MBEDTLS_PRIVATE(endpoint);
2133 }
2134
2135 /**
2136 * \brief Set the transport type (TLS or DTLS).
2137 * Default: TLS
2138 *
2139 * \note For DTLS, you must either provide a recv callback that
2140 * doesn't block, or one that handles timeouts, see
2141 * \c mbedtls_ssl_set_bio(). You also need to provide timer
2142 * callbacks with \c mbedtls_ssl_set_timer_cb().
2143 *
2144 * \param conf SSL configuration
2145 * \param transport transport type:
2146 * MBEDTLS_SSL_TRANSPORT_STREAM for TLS,
2147 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS.
2148 */
2149 void mbedtls_ssl_conf_transport(mbedtls_ssl_config *conf, int transport);
2150
2151 /**
2152 * \brief Set the certificate verification mode
2153 * Default: NONE on server, REQUIRED on client
2154 *
2155 * \param conf SSL configuration
2156 * \param authmode can be:
2157 *
2158 * MBEDTLS_SSL_VERIFY_NONE: peer certificate is not checked
2159 * (default on server)
2160 * (insecure on client)
2161 *
2162 * MBEDTLS_SSL_VERIFY_OPTIONAL: peer certificate is checked, however the
2163 * handshake continues even if verification failed;
2164 * mbedtls_ssl_get_verify_result() can be called after the
2165 * handshake is complete.
2166 *
2167 * MBEDTLS_SSL_VERIFY_REQUIRED: peer *must* present a valid certificate,
2168 * handshake is aborted if verification failed.
2169 * (default on client)
2170 *
2171 * \note On client, MBEDTLS_SSL_VERIFY_REQUIRED is the recommended mode.
2172 * With MBEDTLS_SSL_VERIFY_OPTIONAL, the user needs to call mbedtls_ssl_get_verify_result() at
2173 * the right time(s), which may not be obvious, while REQUIRED always perform
2174 * the verification as soon as possible. For example, REQUIRED was protecting
2175 * against the "triple handshake" attack even before it was found.
2176 */
2177 void mbedtls_ssl_conf_authmode(mbedtls_ssl_config *conf, int authmode);
2178
2179 #if defined(MBEDTLS_SSL_EARLY_DATA)
2180 /**
2181 * \brief Set the early data mode
2182 * Default: disabled on server and client
2183 *
2184 * \param conf The SSL configuration to use.
2185 * \param early_data_enabled can be:
2186 *
2187 * MBEDTLS_SSL_EARLY_DATA_DISABLED:
2188 * Early data functionality is disabled. This is the default on client and
2189 * server.
2190 *
2191 * MBEDTLS_SSL_EARLY_DATA_ENABLED:
2192 * Early data functionality is enabled and may be negotiated in the handshake.
2193 * Application using early data functionality needs to be aware that the
2194 * security properties for early data (also refered to as 0-RTT data) are
2195 * weaker than those for other kinds of TLS data. See the documentation of
2196 * mbedtls_ssl_write_early_data() and mbedtls_ssl_read_early_data() for more
2197 * information.
2198 * When early data functionality is enabled on server and only in that case,
2199 * the call to one of the APIs that trigger or resume an handshake sequence,
2200 * namely mbedtls_ssl_handshake(), mbedtls_ssl_handshake_step(),
2201 * mbedtls_ssl_read() or mbedtls_ssl_write() may return with the error code
2202 * MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA indicating that some early data have
2203 * been received. To read the early data, call mbedtls_ssl_read_early_data()
2204 * before calling the original function again.
2205 */
2206 void mbedtls_ssl_conf_early_data(mbedtls_ssl_config *conf,
2207 int early_data_enabled);
2208
2209 #if defined(MBEDTLS_SSL_SRV_C)
2210 /**
2211 * \brief Set the maximum amount of 0-RTT data in bytes
2212 * Default: #MBEDTLS_SSL_MAX_EARLY_DATA_SIZE
2213 *
2214 * This function sets the value of the max_early_data_size
2215 * field of the early data indication extension included in
2216 * the NewSessionTicket messages that the server may send.
2217 *
2218 * The value defines the maximum amount of 0-RTT data
2219 * in bytes that a client will be allowed to send when using
2220 * one of the tickets defined by the NewSessionTicket messages.
2221 *
2222 * \note When resuming a session using a ticket, if the server receives more
2223 * early data than allowed for the ticket, it terminates the connection.
2224 * The maximum amount of 0-RTT data should thus be large enough
2225 * to allow a minimum of early data to be exchanged.
2226 *
2227 * \param[in] conf The SSL configuration to use.
2228 * \param[in] max_early_data_size The maximum amount of 0-RTT data.
2229 *
2230 * \warning This interface DOES NOT influence/limit the amount of early data
2231 * that can be received through previously created and issued tickets,
2232 * which clients may have stored.
2233 */
2234 void mbedtls_ssl_conf_max_early_data_size(
2235 mbedtls_ssl_config *conf, uint32_t max_early_data_size);
2236 #endif /* MBEDTLS_SSL_SRV_C */
2237
2238 #endif /* MBEDTLS_SSL_EARLY_DATA */
2239
2240 #if defined(MBEDTLS_X509_CRT_PARSE_C)
2241 /**
2242 * \brief Set the verification callback (Optional).
2243 *
2244 * If set, the provided verify callback is called for each
2245 * certificate in the peer's CRT chain, including the trusted
2246 * root. For more information, please see the documentation of
2247 * \c mbedtls_x509_crt_verify().
2248 *
2249 * \note For per context callbacks and contexts, please use
2250 * mbedtls_ssl_set_verify() instead.
2251 *
2252 * \param conf The SSL configuration to use.
2253 * \param f_vrfy The verification callback to use during CRT verification.
2254 * \param p_vrfy The opaque context to be passed to the callback.
2255 */
2256 void mbedtls_ssl_conf_verify(mbedtls_ssl_config *conf,
2257 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2258 void *p_vrfy);
2259 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2260
2261 /**
2262 * \brief Set the random number generator callback
2263 *
2264 * \note The callback with its parameter must remain valid as
2265 * long as there is an SSL context that uses the
2266 * SSL configuration.
2267 *
2268 * \param conf SSL configuration
2269 * \param f_rng RNG function (mandatory)
2270 * \param p_rng RNG parameter
2271 */
2272 void mbedtls_ssl_conf_rng(mbedtls_ssl_config *conf,
2273 mbedtls_f_rng_t *f_rng,
2274 void *p_rng);
2275
2276 /**
2277 * \brief Set the debug callback
2278 *
2279 * The callback has the following argument:
2280 * void * opaque context for the callback
2281 * int debug level
2282 * const char * file name
2283 * int line number
2284 * const char * message
2285 *
2286 * \param conf SSL configuration
2287 * \param f_dbg debug function
2288 * \param p_dbg debug parameter
2289 */
2290 void mbedtls_ssl_conf_dbg(mbedtls_ssl_config *conf,
2291 void (*f_dbg)(void *, int, const char *, int, const char *),
2292 void *p_dbg);
2293
2294 /**
2295 * \brief Return the SSL configuration structure associated
2296 * with the given SSL context.
2297 *
2298 * \note The pointer returned by this function is guaranteed to
2299 * remain valid until the context is freed.
2300 *
2301 * \param ssl The SSL context to query.
2302 * \return Pointer to the SSL configuration associated with \p ssl.
2303 */
mbedtls_ssl_context_get_config(const mbedtls_ssl_context * ssl)2304 static inline const mbedtls_ssl_config *mbedtls_ssl_context_get_config(
2305 const mbedtls_ssl_context *ssl)
2306 {
2307 return ssl->MBEDTLS_PRIVATE(conf);
2308 }
2309
2310 /**
2311 * \brief Set the underlying BIO callbacks for write, read and
2312 * read-with-timeout.
2313 *
2314 * \param ssl SSL context
2315 * \param p_bio parameter (context) shared by BIO callbacks
2316 * \param f_send write callback
2317 * \param f_recv read callback
2318 * \param f_recv_timeout blocking read callback with timeout.
2319 *
2320 * \note One of f_recv or f_recv_timeout can be NULL, in which case
2321 * the other is used. If both are non-NULL, f_recv_timeout is
2322 * used and f_recv is ignored (as if it were NULL).
2323 *
2324 * \note The two most common use cases are:
2325 * - non-blocking I/O, f_recv != NULL, f_recv_timeout == NULL
2326 * - blocking I/O, f_recv == NULL, f_recv_timeout != NULL
2327 *
2328 * \note For DTLS, you need to provide either a non-NULL
2329 * f_recv_timeout callback, or a f_recv that doesn't block.
2330 *
2331 * \note See the documentations of \c mbedtls_ssl_send_t,
2332 * \c mbedtls_ssl_recv_t and \c mbedtls_ssl_recv_timeout_t for
2333 * the conventions those callbacks must follow.
2334 *
2335 * \note On some platforms, net_sockets.c provides
2336 * \c mbedtls_net_send(), \c mbedtls_net_recv() and
2337 * \c mbedtls_net_recv_timeout() that are suitable to be used
2338 * here.
2339 */
2340 void mbedtls_ssl_set_bio(mbedtls_ssl_context *ssl,
2341 void *p_bio,
2342 mbedtls_ssl_send_t *f_send,
2343 mbedtls_ssl_recv_t *f_recv,
2344 mbedtls_ssl_recv_timeout_t *f_recv_timeout);
2345
2346 #if defined(MBEDTLS_SSL_PROTO_DTLS)
2347
2348 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
2349
2350
2351 /**
2352 * \brief Configure the use of the Connection ID (CID)
2353 * extension in the next handshake.
2354 *
2355 * Reference: RFC 9146 (or draft-ietf-tls-dtls-connection-id-05
2356 * https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05
2357 * for legacy version)
2358 *
2359 * The DTLS CID extension allows the reliable association of
2360 * DTLS records to DTLS connections across changes in the
2361 * underlying transport (changed IP and Port metadata) by
2362 * adding explicit connection identifiers (CIDs) to the
2363 * headers of encrypted DTLS records. The desired CIDs are
2364 * configured by the application layer and are exchanged in
2365 * new `ClientHello` / `ServerHello` extensions during the
2366 * handshake, where each side indicates the CID it wants the
2367 * peer to use when writing encrypted messages. The CIDs are
2368 * put to use once records get encrypted: the stack discards
2369 * any incoming records that don't include the configured CID
2370 * in their header, and adds the peer's requested CID to the
2371 * headers of outgoing messages.
2372 *
2373 * This API enables or disables the use of the CID extension
2374 * in the next handshake and sets the value of the CID to
2375 * be used for incoming messages.
2376 *
2377 * \param ssl The SSL context to configure. This must be initialized.
2378 * \param enable This value determines whether the CID extension should
2379 * be used or not. Possible values are:
2380 * - MBEDTLS_SSL_CID_ENABLED to enable the use of the CID.
2381 * - MBEDTLS_SSL_CID_DISABLED (default) to disable the use
2382 * of the CID.
2383 * \param own_cid The address of the readable buffer holding the CID we want
2384 * the peer to use when sending encrypted messages to us.
2385 * This may be \c NULL if \p own_cid_len is \c 0.
2386 * This parameter is unused if \p enable is set to
2387 * MBEDTLS_SSL_CID_DISABLED.
2388 * \param own_cid_len The length of \p own_cid.
2389 * This parameter is unused if \p enable is set to
2390 * MBEDTLS_SSL_CID_DISABLED.
2391 *
2392 * \note The value of \p own_cid_len must match the value of the
2393 * \c len parameter passed to mbedtls_ssl_conf_cid()
2394 * when configuring the ::mbedtls_ssl_config that \p ssl
2395 * is bound to.
2396 *
2397 * \note This CID configuration applies to subsequent handshakes
2398 * performed on the SSL context \p ssl, but does not trigger
2399 * one. You still have to call `mbedtls_ssl_handshake()`
2400 * (for the initial handshake) or `mbedtls_ssl_renegotiate()`
2401 * (for a renegotiation handshake) explicitly after a
2402 * successful call to this function to run the handshake.
2403 *
2404 * \note This call cannot guarantee that the use of the CID
2405 * will be successfully negotiated in the next handshake,
2406 * because the peer might not support it. Specifically:
2407 * - On the Client, enabling the use of the CID through
2408 * this call implies that the `ClientHello` in the next
2409 * handshake will include the CID extension, thereby
2410 * offering the use of the CID to the server. Only if
2411 * the `ServerHello` contains the CID extension, too,
2412 * the CID extension will actually be put to use.
2413 * - On the Server, enabling the use of the CID through
2414 * this call implies that the server will look for
2415 * the CID extension in a `ClientHello` from the client,
2416 * and, if present, reply with a CID extension in its
2417 * `ServerHello`.
2418 *
2419 * \note To check whether the use of the CID was negotiated
2420 * after the subsequent handshake has completed, please
2421 * use the API mbedtls_ssl_get_peer_cid().
2422 *
2423 * \warning If the use of the CID extension is enabled in this call
2424 * and the subsequent handshake negotiates its use, Mbed TLS
2425 * will silently drop every packet whose CID does not match
2426 * the CID configured in \p own_cid. It is the responsibility
2427 * of the user to adapt the underlying transport to take care
2428 * of CID-based demultiplexing before handing datagrams to
2429 * Mbed TLS.
2430 *
2431 * \return \c 0 on success. In this case, the CID configuration
2432 * applies to the next handshake.
2433 * \return A negative error code on failure.
2434 */
2435 int mbedtls_ssl_set_cid(mbedtls_ssl_context *ssl,
2436 int enable,
2437 unsigned char const *own_cid,
2438 size_t own_cid_len);
2439
2440 /**
2441 * \brief Get information about our request for usage of the CID
2442 * extension in the current connection.
2443 *
2444 * \param ssl The SSL context to query.
2445 * \param enabled The address at which to store whether the CID extension
2446 * is requested to be used or not. If the CID is
2447 * requested, `*enabled` is set to
2448 * MBEDTLS_SSL_CID_ENABLED; otherwise, it is set to
2449 * MBEDTLS_SSL_CID_DISABLED.
2450 * \param own_cid The address of the buffer in which to store our own
2451 * CID (if the CID extension is requested). This may be
2452 * \c NULL in case the value of our CID isn't needed. If
2453 * it is not \c NULL, \p own_cid_len must not be \c NULL.
2454 * \param own_cid_len The address at which to store the size of our own CID
2455 * (if the CID extension is requested). This is also the
2456 * number of Bytes in \p own_cid that have been written.
2457 * This may be \c NULL in case the length of our own CID
2458 * isn't needed. If it is \c NULL, \p own_cid must be
2459 * \c NULL, too.
2460 *
2461 *\note If we are requesting an empty CID this function sets
2462 * `*enabled` to #MBEDTLS_SSL_CID_DISABLED (the rationale
2463 * for this is that the resulting outcome is the
2464 * same as if the CID extensions wasn't requested).
2465 *
2466 * \return \c 0 on success.
2467 * \return A negative error code on failure.
2468 */
2469 int mbedtls_ssl_get_own_cid(mbedtls_ssl_context *ssl,
2470 int *enabled,
2471 unsigned char own_cid[MBEDTLS_SSL_CID_IN_LEN_MAX],
2472 size_t *own_cid_len);
2473
2474 /**
2475 * \brief Get information about the use of the CID extension
2476 * in the current connection.
2477 *
2478 * \param ssl The SSL context to query.
2479 * \param enabled The address at which to store whether the CID extension
2480 * is currently in use or not. If the CID is in use,
2481 * `*enabled` is set to MBEDTLS_SSL_CID_ENABLED;
2482 * otherwise, it is set to MBEDTLS_SSL_CID_DISABLED.
2483 * \param peer_cid The address of the buffer in which to store the CID
2484 * chosen by the peer (if the CID extension is used).
2485 * This may be \c NULL in case the value of peer CID
2486 * isn't needed. If it is not \c NULL, \p peer_cid_len
2487 * must not be \c NULL.
2488 * \param peer_cid_len The address at which to store the size of the CID
2489 * chosen by the peer (if the CID extension is used).
2490 * This is also the number of Bytes in \p peer_cid that
2491 * have been written.
2492 * This may be \c NULL in case the length of the peer CID
2493 * isn't needed. If it is \c NULL, \p peer_cid must be
2494 * \c NULL, too.
2495 *
2496 * \note This applies to the state of the CID negotiated in
2497 * the last complete handshake. If a handshake is in
2498 * progress, this function will attempt to complete
2499 * the handshake first.
2500 *
2501 * \note If CID extensions have been exchanged but both client
2502 * and server chose to use an empty CID, this function
2503 * sets `*enabled` to #MBEDTLS_SSL_CID_DISABLED
2504 * (the rationale for this is that the resulting
2505 * communication is the same as if the CID extensions
2506 * hadn't been used).
2507 *
2508 * \return \c 0 on success.
2509 * \return A negative error code on failure.
2510 */
2511 int mbedtls_ssl_get_peer_cid(mbedtls_ssl_context *ssl,
2512 int *enabled,
2513 unsigned char peer_cid[MBEDTLS_SSL_CID_OUT_LEN_MAX],
2514 size_t *peer_cid_len);
2515
2516 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
2517
2518 /**
2519 * \brief Set the Maximum Transport Unit (MTU).
2520 * Special value: 0 means unset (no limit).
2521 * This represents the maximum size of a datagram payload
2522 * handled by the transport layer (usually UDP) as determined
2523 * by the network link and stack. In practice, this controls
2524 * the maximum size datagram the DTLS layer will pass to the
2525 * \c f_send() callback set using \c mbedtls_ssl_set_bio().
2526 *
2527 * \note The limit on datagram size is converted to a limit on
2528 * record payload by subtracting the current overhead of
2529 * encapsulation and encryption/authentication if any.
2530 *
2531 * \note This can be called at any point during the connection, for
2532 * example when a Path Maximum Transfer Unit (PMTU)
2533 * estimate becomes available from other sources,
2534 * such as lower (or higher) protocol layers.
2535 *
2536 * \note This setting only controls the size of the packets we send,
2537 * and does not restrict the size of the datagrams we're
2538 * willing to receive. Client-side, you can request the
2539 * server to use smaller records with \c
2540 * mbedtls_ssl_conf_max_frag_len().
2541 *
2542 * \note If both a MTU and a maximum fragment length have been
2543 * configured (or negotiated with the peer), the resulting
2544 * lower limit on record payload (see first note) is used.
2545 *
2546 * \note This can only be used to decrease the maximum size
2547 * of datagrams (hence records, see first note) sent. It
2548 * cannot be used to increase the maximum size of records over
2549 * the limit set by #MBEDTLS_SSL_OUT_CONTENT_LEN.
2550 *
2551 * \note Values lower than the current record layer expansion will
2552 * result in an error when trying to send data.
2553 *
2554 * \param ssl SSL context
2555 * \param mtu Value of the path MTU in bytes
2556 */
2557 void mbedtls_ssl_set_mtu(mbedtls_ssl_context *ssl, uint16_t mtu);
2558 #endif /* MBEDTLS_SSL_PROTO_DTLS */
2559
2560 #if defined(MBEDTLS_X509_CRT_PARSE_C)
2561 /**
2562 * \brief Set a connection-specific verification callback (optional).
2563 *
2564 * If set, the provided verify callback is called for each
2565 * certificate in the peer's CRT chain, including the trusted
2566 * root. For more information, please see the documentation of
2567 * \c mbedtls_x509_crt_verify().
2568 *
2569 * \note This call is analogous to mbedtls_ssl_conf_verify() but
2570 * binds the verification callback and context to an SSL context
2571 * as opposed to an SSL configuration.
2572 * If mbedtls_ssl_conf_verify() and mbedtls_ssl_set_verify()
2573 * are both used, mbedtls_ssl_set_verify() takes precedence.
2574 *
2575 * \param ssl The SSL context to use.
2576 * \param f_vrfy The verification callback to use during CRT verification.
2577 * \param p_vrfy The opaque context to be passed to the callback.
2578 */
2579 void mbedtls_ssl_set_verify(mbedtls_ssl_context *ssl,
2580 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2581 void *p_vrfy);
2582 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2583
2584 /**
2585 * \brief Set the timeout period for mbedtls_ssl_read()
2586 * (Default: no timeout.)
2587 *
2588 * \param conf SSL configuration context
2589 * \param timeout Timeout value in milliseconds.
2590 * Use 0 for no timeout (default).
2591 *
2592 * \note With blocking I/O, this will only work if a non-NULL
2593 * \c f_recv_timeout was set with \c mbedtls_ssl_set_bio().
2594 * With non-blocking I/O, this will only work if timer
2595 * callbacks were set with \c mbedtls_ssl_set_timer_cb().
2596 *
2597 * \note With non-blocking I/O, you may also skip this function
2598 * altogether and handle timeouts at the application layer.
2599 */
2600 void mbedtls_ssl_conf_read_timeout(mbedtls_ssl_config *conf, uint32_t timeout);
2601
2602 /**
2603 * \brief Check whether a buffer contains a valid and authentic record
2604 * that has not been seen before. (DTLS only).
2605 *
2606 * This function does not change the user-visible state
2607 * of the SSL context. Its sole purpose is to provide
2608 * an indication of the legitimacy of an incoming record.
2609 *
2610 * This can be useful e.g. in distributed server environments
2611 * using the DTLS Connection ID feature, in which connections
2612 * might need to be passed between service instances on a change
2613 * of peer address, but where such disruptive operations should
2614 * only happen after the validity of incoming records has been
2615 * confirmed.
2616 *
2617 * \param ssl The SSL context to use.
2618 * \param buf The address of the buffer holding the record to be checked.
2619 * This must be a read/write buffer of length \p buflen Bytes.
2620 * \param buflen The length of \p buf in Bytes.
2621 *
2622 * \note This routine only checks whether the provided buffer begins
2623 * with a valid and authentic record that has not been seen
2624 * before, but does not check potential data following the
2625 * initial record. In particular, it is possible to pass DTLS
2626 * datagrams containing multiple records, in which case only
2627 * the first record is checked.
2628 *
2629 * \note This function modifies the input buffer \p buf. If you need
2630 * to preserve the original record, you have to maintain a copy.
2631 *
2632 * \return \c 0 if the record is valid and authentic and has not been
2633 * seen before.
2634 * \return MBEDTLS_ERR_SSL_INVALID_MAC if the check completed
2635 * successfully but the record was found to be not authentic.
2636 * \return MBEDTLS_ERR_SSL_INVALID_RECORD if the check completed
2637 * successfully but the record was found to be invalid for
2638 * a reason different from authenticity checking.
2639 * \return MBEDTLS_ERR_SSL_UNEXPECTED_RECORD if the check completed
2640 * successfully but the record was found to be unexpected
2641 * in the state of the SSL context, including replayed records.
2642 * \return Another negative error code on different kinds of failure.
2643 * In this case, the SSL context becomes unusable and needs
2644 * to be freed or reset before reuse.
2645 */
2646 int mbedtls_ssl_check_record(mbedtls_ssl_context const *ssl,
2647 unsigned char *buf,
2648 size_t buflen);
2649
2650 /**
2651 * \brief Set the timer callbacks (Mandatory for DTLS.)
2652 *
2653 * \param ssl SSL context
2654 * \param p_timer parameter (context) shared by timer callbacks
2655 * \param f_set_timer set timer callback
2656 * \param f_get_timer get timer callback. Must return:
2657 *
2658 * \note See the documentation of \c mbedtls_ssl_set_timer_t and
2659 * \c mbedtls_ssl_get_timer_t for the conventions this pair of
2660 * callbacks must follow.
2661 *
2662 * \note On some platforms, timing.c provides
2663 * \c mbedtls_timing_set_delay() and
2664 * \c mbedtls_timing_get_delay() that are suitable for using
2665 * here, except if using an event-driven style.
2666 *
2667 * \note See also the "DTLS tutorial" article in our knowledge base.
2668 * https://mbed-tls.readthedocs.io/en/latest/kb/how-to/dtls-tutorial
2669 */
2670 void mbedtls_ssl_set_timer_cb(mbedtls_ssl_context *ssl,
2671 void *p_timer,
2672 mbedtls_ssl_set_timer_t *f_set_timer,
2673 mbedtls_ssl_get_timer_t *f_get_timer);
2674
2675 #if defined(MBEDTLS_SSL_SRV_C)
2676 /**
2677 * \brief Set the certificate selection callback (server-side only).
2678 *
2679 * If set, the callback is always called for each handshake,
2680 * after `ClientHello` processing has finished.
2681 *
2682 * \param conf The SSL configuration to register the callback with.
2683 * \param f_cert_cb The callback for selecting server certificate after
2684 * `ClientHello` processing has finished.
2685 */
mbedtls_ssl_conf_cert_cb(mbedtls_ssl_config * conf,mbedtls_ssl_hs_cb_t f_cert_cb)2686 static inline void mbedtls_ssl_conf_cert_cb(mbedtls_ssl_config *conf,
2687 mbedtls_ssl_hs_cb_t f_cert_cb)
2688 {
2689 conf->MBEDTLS_PRIVATE(f_cert_cb) = f_cert_cb;
2690 }
2691 #endif /* MBEDTLS_SSL_SRV_C */
2692
2693 /**
2694 * \brief Callback type: generate and write session ticket
2695 *
2696 * \note This describes what a callback implementation should do.
2697 * This callback should generate an encrypted and
2698 * authenticated ticket for the session and write it to the
2699 * output buffer. Here, ticket means the opaque ticket part
2700 * of the NewSessionTicket structure of RFC 5077.
2701 *
2702 * \param p_ticket Context for the callback
2703 * \param session SSL session to be written in the ticket
2704 * \param start Start of the output buffer
2705 * \param end End of the output buffer
2706 * \param tlen On exit, holds the length written
2707 * \param lifetime On exit, holds the lifetime of the ticket in seconds
2708 *
2709 * \return 0 if successful, or
2710 * a specific MBEDTLS_ERR_XXX code.
2711 */
2712 typedef int mbedtls_ssl_ticket_write_t(void *p_ticket,
2713 const mbedtls_ssl_session *session,
2714 unsigned char *start,
2715 const unsigned char *end,
2716 size_t *tlen,
2717 uint32_t *lifetime);
2718
2719 /**
2720 * \brief Callback type: parse and load session ticket
2721 *
2722 * \note This describes what a callback implementation should do.
2723 * This callback should parse a session ticket as generated
2724 * by the corresponding mbedtls_ssl_ticket_write_t function,
2725 * and, if the ticket is authentic and valid, load the
2726 * session.
2727 *
2728 * \note The implementation is allowed to modify the first len
2729 * bytes of the input buffer, eg to use it as a temporary
2730 * area for the decrypted ticket contents.
2731 *
2732 * \param p_ticket Context for the callback
2733 * \param session SSL session to be loaded
2734 * \param buf Start of the buffer containing the ticket
2735 * \param len Length of the ticket.
2736 *
2737 * \return 0 if successful, or
2738 * MBEDTLS_ERR_SSL_INVALID_MAC if not authentic, or
2739 * MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED if expired, or
2740 * any other non-zero code for other failures.
2741 */
2742 typedef int mbedtls_ssl_ticket_parse_t(void *p_ticket,
2743 mbedtls_ssl_session *session,
2744 unsigned char *buf,
2745 size_t len);
2746
2747 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
2748 /**
2749 * \brief Configure SSL session ticket callbacks (server only).
2750 * (Default: none.)
2751 *
2752 * \note On server, session tickets are enabled by providing
2753 * non-NULL callbacks.
2754 *
2755 * \note On client, use \c mbedtls_ssl_conf_session_tickets().
2756 *
2757 * \param conf SSL configuration context
2758 * \param f_ticket_write Callback for writing a ticket
2759 * \param f_ticket_parse Callback for parsing a ticket
2760 * \param p_ticket Context shared by the two callbacks
2761 */
2762 void mbedtls_ssl_conf_session_tickets_cb(mbedtls_ssl_config *conf,
2763 mbedtls_ssl_ticket_write_t *f_ticket_write,
2764 mbedtls_ssl_ticket_parse_t *f_ticket_parse,
2765 void *p_ticket);
2766
2767 #if defined(MBEDTLS_HAVE_TIME)
2768 /**
2769 * \brief Get the creation time of a session ticket.
2770 *
2771 * \note See the documentation of \c ticket_creation_time for information about
2772 * the intended usage of this function.
2773 *
2774 * \param session SSL session
2775 * \param ticket_creation_time On exit, holds the ticket creation time in
2776 * milliseconds.
2777 *
2778 * \return 0 on success,
2779 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if an input is not valid.
2780 */
mbedtls_ssl_session_get_ticket_creation_time(mbedtls_ssl_session * session,mbedtls_ms_time_t * ticket_creation_time)2781 static inline int mbedtls_ssl_session_get_ticket_creation_time(
2782 mbedtls_ssl_session *session, mbedtls_ms_time_t *ticket_creation_time)
2783 {
2784 if (session == NULL || ticket_creation_time == NULL ||
2785 session->MBEDTLS_PRIVATE(endpoint) != MBEDTLS_SSL_IS_SERVER) {
2786 return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
2787 }
2788
2789 *ticket_creation_time = session->MBEDTLS_PRIVATE(ticket_creation_time);
2790
2791 return 0;
2792 }
2793 #endif /* MBEDTLS_HAVE_TIME */
2794 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
2795
2796 /**
2797 * \brief Get the session-id buffer.
2798 *
2799 * \param session SSL session.
2800 *
2801 * \return The address of the session-id buffer.
2802 */
mbedtls_ssl_session_get_id(const mbedtls_ssl_session * session)2803 static inline unsigned const char (*mbedtls_ssl_session_get_id(const mbedtls_ssl_session *
2804 session))[32]
2805 {
2806 return &session->MBEDTLS_PRIVATE(id);
2807 }
2808
2809 /**
2810 * \brief Get the size of the session-id.
2811 *
2812 * \param session SSL session.
2813 *
2814 * \return size_t size of session-id buffer.
2815 */
mbedtls_ssl_session_get_id_len(const mbedtls_ssl_session * session)2816 static inline size_t mbedtls_ssl_session_get_id_len(const mbedtls_ssl_session *session)
2817 {
2818 return session->MBEDTLS_PRIVATE(id_len);
2819 }
2820
2821 /**
2822 * \brief Get the ciphersuite-id.
2823 *
2824 * \param session SSL session.
2825 *
2826 * \return int represetation for ciphersuite.
2827 */
mbedtls_ssl_session_get_ciphersuite_id(const mbedtls_ssl_session * session)2828 static inline int mbedtls_ssl_session_get_ciphersuite_id(const mbedtls_ssl_session *session)
2829 {
2830 return session->MBEDTLS_PRIVATE(ciphersuite);
2831 }
2832
2833 /**
2834 * \brief Configure a key export callback.
2835 * (Default: none.)
2836 *
2837 * This API can be used for two purposes:
2838 * - Debugging: Use this API to e.g. generate an NSSKeylog
2839 * file and use it to inspect encrypted traffic in tools
2840 * such as Wireshark.
2841 * - Application-specific export: Use this API to implement
2842 * key exporters, e.g. for EAP-TLS or DTLS-SRTP.
2843 *
2844 *
2845 * \param ssl The SSL context to which the export
2846 * callback should be attached.
2847 * \param f_export_keys The callback for the key export.
2848 * \param p_export_keys The opaque context pointer to be passed to the
2849 * callback \p f_export_keys.
2850 */
2851 void mbedtls_ssl_set_export_keys_cb(mbedtls_ssl_context *ssl,
2852 mbedtls_ssl_export_keys_t *f_export_keys,
2853 void *p_export_keys);
2854
2855 /** \brief Set the user data in an SSL configuration to a pointer.
2856 *
2857 * You can retrieve this value later with mbedtls_ssl_conf_get_user_data_p().
2858 *
2859 * \note The library stores \c p without accessing it. It is the responsibility
2860 * of the caller to ensure that the pointer remains valid.
2861 *
2862 * \param conf The SSL configuration context to modify.
2863 * \param p The new value of the user data.
2864 */
mbedtls_ssl_conf_set_user_data_p(mbedtls_ssl_config * conf,void * p)2865 static inline void mbedtls_ssl_conf_set_user_data_p(
2866 mbedtls_ssl_config *conf,
2867 void *p)
2868 {
2869 conf->MBEDTLS_PRIVATE(user_data).p = p;
2870 }
2871
2872 /** \brief Set the user data in an SSL configuration to an integer.
2873 *
2874 * You can retrieve this value later with mbedtls_ssl_conf_get_user_data_n().
2875 *
2876 * \param conf The SSL configuration context to modify.
2877 * \param n The new value of the user data.
2878 */
mbedtls_ssl_conf_set_user_data_n(mbedtls_ssl_config * conf,uintptr_t n)2879 static inline void mbedtls_ssl_conf_set_user_data_n(
2880 mbedtls_ssl_config *conf,
2881 uintptr_t n)
2882 {
2883 conf->MBEDTLS_PRIVATE(user_data).n = n;
2884 }
2885
2886 /** \brief Retrieve the user data in an SSL configuration as a pointer.
2887 *
2888 * This is the value last set with mbedtls_ssl_conf_set_user_data_p(), or
2889 * \c NULL if mbedtls_ssl_conf_set_user_data_p() has not previously been
2890 * called. The value is undefined if mbedtls_ssl_conf_set_user_data_n() has
2891 * been called without a subsequent call to mbedtls_ssl_conf_set_user_data_p().
2892 *
2893 * \param conf The SSL configuration context to modify.
2894 * \return The current value of the user data.
2895 */
mbedtls_ssl_conf_get_user_data_p(mbedtls_ssl_config * conf)2896 static inline void *mbedtls_ssl_conf_get_user_data_p(
2897 mbedtls_ssl_config *conf)
2898 {
2899 return conf->MBEDTLS_PRIVATE(user_data).p;
2900 }
2901
2902 /** \brief Retrieve the user data in an SSL configuration as an integer.
2903 *
2904 * This is the value last set with mbedtls_ssl_conf_set_user_data_n(), or
2905 * \c 0 if mbedtls_ssl_conf_set_user_data_n() has not previously been
2906 * called. The value is undefined if mbedtls_ssl_conf_set_user_data_p() has
2907 * been called without a subsequent call to mbedtls_ssl_conf_set_user_data_n().
2908 *
2909 * \param conf The SSL configuration context to modify.
2910 * \return The current value of the user data.
2911 */
mbedtls_ssl_conf_get_user_data_n(mbedtls_ssl_config * conf)2912 static inline uintptr_t mbedtls_ssl_conf_get_user_data_n(
2913 mbedtls_ssl_config *conf)
2914 {
2915 return conf->MBEDTLS_PRIVATE(user_data).n;
2916 }
2917
2918 /** \brief Set the user data in an SSL context to a pointer.
2919 *
2920 * You can retrieve this value later with mbedtls_ssl_get_user_data_p().
2921 *
2922 * \note The library stores \c p without accessing it. It is the responsibility
2923 * of the caller to ensure that the pointer remains valid.
2924 *
2925 * \param ssl The SSL context to modify.
2926 * \param p The new value of the user data.
2927 */
mbedtls_ssl_set_user_data_p(mbedtls_ssl_context * ssl,void * p)2928 static inline void mbedtls_ssl_set_user_data_p(
2929 mbedtls_ssl_context *ssl,
2930 void *p)
2931 {
2932 ssl->MBEDTLS_PRIVATE(user_data).p = p;
2933 }
2934
2935 /** \brief Set the user data in an SSL context to an integer.
2936 *
2937 * You can retrieve this value later with mbedtls_ssl_get_user_data_n().
2938 *
2939 * \param ssl The SSL context to modify.
2940 * \param n The new value of the user data.
2941 */
mbedtls_ssl_set_user_data_n(mbedtls_ssl_context * ssl,uintptr_t n)2942 static inline void mbedtls_ssl_set_user_data_n(
2943 mbedtls_ssl_context *ssl,
2944 uintptr_t n)
2945 {
2946 ssl->MBEDTLS_PRIVATE(user_data).n = n;
2947 }
2948
2949 /** \brief Retrieve the user data in an SSL context as a pointer.
2950 *
2951 * This is the value last set with mbedtls_ssl_set_user_data_p(), or
2952 * \c NULL if mbedtls_ssl_set_user_data_p() has not previously been
2953 * called. The value is undefined if mbedtls_ssl_set_user_data_n() has
2954 * been called without a subsequent call to mbedtls_ssl_set_user_data_p().
2955 *
2956 * \param ssl The SSL context to modify.
2957 * \return The current value of the user data.
2958 */
mbedtls_ssl_get_user_data_p(mbedtls_ssl_context * ssl)2959 static inline void *mbedtls_ssl_get_user_data_p(
2960 mbedtls_ssl_context *ssl)
2961 {
2962 return ssl->MBEDTLS_PRIVATE(user_data).p;
2963 }
2964
2965 /** \brief Retrieve the user data in an SSL context as an integer.
2966 *
2967 * This is the value last set with mbedtls_ssl_set_user_data_n(), or
2968 * \c 0 if mbedtls_ssl_set_user_data_n() has not previously been
2969 * called. The value is undefined if mbedtls_ssl_set_user_data_p() has
2970 * been called without a subsequent call to mbedtls_ssl_set_user_data_n().
2971 *
2972 * \param ssl The SSL context to modify.
2973 * \return The current value of the user data.
2974 */
mbedtls_ssl_get_user_data_n(mbedtls_ssl_context * ssl)2975 static inline uintptr_t mbedtls_ssl_get_user_data_n(
2976 mbedtls_ssl_context *ssl)
2977 {
2978 return ssl->MBEDTLS_PRIVATE(user_data).n;
2979 }
2980
2981 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
2982 /**
2983 * \brief Configure asynchronous private key operation callbacks.
2984 *
2985 * \param conf SSL configuration context
2986 * \param f_async_sign Callback to start a signature operation. See
2987 * the description of ::mbedtls_ssl_async_sign_t
2988 * for more information. This may be \c NULL if the
2989 * external processor does not support any signature
2990 * operation; in this case the private key object
2991 * associated with the certificate will be used.
2992 * \param f_async_decrypt Callback to start a decryption operation. See
2993 * the description of ::mbedtls_ssl_async_decrypt_t
2994 * for more information. This may be \c NULL if the
2995 * external processor does not support any decryption
2996 * operation; in this case the private key object
2997 * associated with the certificate will be used.
2998 * \param f_async_resume Callback to resume an asynchronous operation. See
2999 * the description of ::mbedtls_ssl_async_resume_t
3000 * for more information. This may not be \c NULL unless
3001 * \p f_async_sign and \p f_async_decrypt are both
3002 * \c NULL.
3003 * \param f_async_cancel Callback to cancel an asynchronous operation. See
3004 * the description of ::mbedtls_ssl_async_cancel_t
3005 * for more information. This may be \c NULL if
3006 * no cleanup is needed.
3007 * \param config_data A pointer to configuration data which can be
3008 * retrieved with
3009 * mbedtls_ssl_conf_get_async_config_data(). The
3010 * library stores this value without dereferencing it.
3011 */
3012 void mbedtls_ssl_conf_async_private_cb(mbedtls_ssl_config *conf,
3013 mbedtls_ssl_async_sign_t *f_async_sign,
3014 mbedtls_ssl_async_decrypt_t *f_async_decrypt,
3015 mbedtls_ssl_async_resume_t *f_async_resume,
3016 mbedtls_ssl_async_cancel_t *f_async_cancel,
3017 void *config_data);
3018
3019 /**
3020 * \brief Retrieve the configuration data set by
3021 * mbedtls_ssl_conf_async_private_cb().
3022 *
3023 * \param conf SSL configuration context
3024 * \return The configuration data set by
3025 * mbedtls_ssl_conf_async_private_cb().
3026 */
3027 void *mbedtls_ssl_conf_get_async_config_data(const mbedtls_ssl_config *conf);
3028
3029 /**
3030 * \brief Retrieve the asynchronous operation user context.
3031 *
3032 * \note This function may only be called while a handshake
3033 * is in progress.
3034 *
3035 * \param ssl The SSL context to access.
3036 *
3037 * \return The asynchronous operation user context that was last
3038 * set during the current handshake. If
3039 * mbedtls_ssl_set_async_operation_data() has not yet been
3040 * called during the current handshake, this function returns
3041 * \c NULL.
3042 */
3043 void *mbedtls_ssl_get_async_operation_data(const mbedtls_ssl_context *ssl);
3044
3045 /**
3046 * \brief Retrieve the asynchronous operation user context.
3047 *
3048 * \note This function may only be called while a handshake
3049 * is in progress.
3050 *
3051 * \param ssl The SSL context to access.
3052 * \param ctx The new value of the asynchronous operation user context.
3053 * Call mbedtls_ssl_get_async_operation_data() later during the
3054 * same handshake to retrieve this value.
3055 */
3056 void mbedtls_ssl_set_async_operation_data(mbedtls_ssl_context *ssl,
3057 void *ctx);
3058 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
3059
3060 /**
3061 * \brief Callback type: generate a cookie
3062 *
3063 * \param ctx Context for the callback
3064 * \param p Buffer to write to,
3065 * must be updated to point right after the cookie
3066 * \param end Pointer to one past the end of the output buffer
3067 * \param info Client ID info that was passed to
3068 * \c mbedtls_ssl_set_client_transport_id()
3069 * \param ilen Length of info in bytes
3070 *
3071 * \return The callback must return 0 on success,
3072 * or a negative error code.
3073 */
3074 typedef int mbedtls_ssl_cookie_write_t(void *ctx,
3075 unsigned char **p, unsigned char *end,
3076 const unsigned char *info, size_t ilen);
3077
3078 /**
3079 * \brief Callback type: verify a cookie
3080 *
3081 * \param ctx Context for the callback
3082 * \param cookie Cookie to verify
3083 * \param clen Length of cookie
3084 * \param info Client ID info that was passed to
3085 * \c mbedtls_ssl_set_client_transport_id()
3086 * \param ilen Length of info in bytes
3087 *
3088 * \return The callback must return 0 if cookie is valid,
3089 * or a negative error code.
3090 */
3091 typedef int mbedtls_ssl_cookie_check_t(void *ctx,
3092 const unsigned char *cookie, size_t clen,
3093 const unsigned char *info, size_t ilen);
3094
3095 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
3096 /**
3097 * \brief Register callbacks for DTLS cookies
3098 * (Server only. DTLS only.)
3099 *
3100 * Default: dummy callbacks that fail, in order to force you to
3101 * register working callbacks (and initialize their context).
3102 *
3103 * To disable HelloVerifyRequest, register NULL callbacks.
3104 *
3105 * \warning Disabling hello verification allows your server to be used
3106 * for amplification in DoS attacks against other hosts.
3107 * Only disable if you known this can't happen in your
3108 * particular environment.
3109 *
3110 * \note See comments on \c mbedtls_ssl_handshake() about handling
3111 * the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected
3112 * on the first handshake attempt when this is enabled.
3113 *
3114 * \note This is also necessary to handle client reconnection from
3115 * the same port as described in RFC 6347 section 4.2.8 (only
3116 * the variant with cookies is supported currently). See
3117 * comments on \c mbedtls_ssl_read() for details.
3118 *
3119 * \param conf SSL configuration
3120 * \param f_cookie_write Cookie write callback
3121 * \param f_cookie_check Cookie check callback
3122 * \param p_cookie Context for both callbacks
3123 */
3124 void mbedtls_ssl_conf_dtls_cookies(mbedtls_ssl_config *conf,
3125 mbedtls_ssl_cookie_write_t *f_cookie_write,
3126 mbedtls_ssl_cookie_check_t *f_cookie_check,
3127 void *p_cookie);
3128
3129 /**
3130 * \brief Set client's transport-level identification info.
3131 * (Server only. DTLS only.)
3132 *
3133 * This is usually the IP address (and port), but could be
3134 * anything identify the client depending on the underlying
3135 * network stack. Used for HelloVerifyRequest with DTLS.
3136 * This is *not* used to route the actual packets.
3137 *
3138 * \param ssl SSL context
3139 * \param info Transport-level info identifying the client (eg IP + port)
3140 * \param ilen Length of info in bytes
3141 *
3142 * \note An internal copy is made, so the info buffer can be reused.
3143 *
3144 * \return 0 on success,
3145 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client,
3146 * MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory.
3147 */
3148 int mbedtls_ssl_set_client_transport_id(mbedtls_ssl_context *ssl,
3149 const unsigned char *info,
3150 size_t ilen);
3151
3152 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
3153
3154 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
3155 /**
3156 * \brief Enable or disable anti-replay protection for DTLS.
3157 * (DTLS only, no effect on TLS.)
3158 * Default: enabled.
3159 *
3160 * \param conf SSL configuration
3161 * \param mode MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED.
3162 *
3163 * \warning Disabling this is a security risk unless the application
3164 * protocol handles duplicated packets in a safe way. You
3165 * should not disable this without careful consideration.
3166 * However, if your application already detects duplicated
3167 * packets and needs information about them to adjust its
3168 * transmission strategy, then you'll want to disable this.
3169 */
3170 void mbedtls_ssl_conf_dtls_anti_replay(mbedtls_ssl_config *conf, char mode);
3171 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
3172
3173 /**
3174 * \brief Set a limit on the number of records with a bad MAC
3175 * before terminating the connection.
3176 * (DTLS only, no effect on TLS.)
3177 * Default: 0 (disabled).
3178 *
3179 * \param conf SSL configuration
3180 * \param limit Limit, or 0 to disable.
3181 *
3182 * \note If the limit is N, then the connection is terminated when
3183 * the Nth non-authentic record is seen.
3184 *
3185 * \note Records with an invalid header are not counted, only the
3186 * ones going through the authentication-decryption phase.
3187 *
3188 * \note This is a security trade-off related to the fact that it's
3189 * often relatively easy for an active attacker to inject UDP
3190 * datagrams. On one hand, setting a low limit here makes it
3191 * easier for such an attacker to forcibly terminated a
3192 * connection. On the other hand, a high limit or no limit
3193 * might make us waste resources checking authentication on
3194 * many bogus packets.
3195 */
3196 void mbedtls_ssl_conf_dtls_badmac_limit(mbedtls_ssl_config *conf, unsigned limit);
3197
3198 #if defined(MBEDTLS_SSL_PROTO_DTLS)
3199
3200 /**
3201 * \brief Allow or disallow packing of multiple handshake records
3202 * within a single datagram.
3203 *
3204 * \param ssl The SSL context to configure.
3205 * \param allow_packing This determines whether datagram packing may
3206 * be used or not. A value of \c 0 means that every
3207 * record will be sent in a separate datagram; a
3208 * value of \c 1 means that, if space permits,
3209 * multiple handshake messages (including CCS) belonging to
3210 * a single flight may be packed within a single datagram.
3211 *
3212 * \note This is enabled by default and should only be disabled
3213 * for test purposes, or if datagram packing causes
3214 * interoperability issues with peers that don't support it.
3215 *
3216 * \note Allowing datagram packing reduces the network load since
3217 * there's less overhead if multiple messages share the same
3218 * datagram. Also, it increases the handshake efficiency
3219 * since messages belonging to a single datagram will not
3220 * be reordered in transit, and so future message buffering
3221 * or flight retransmission (if no buffering is used) as
3222 * means to deal with reordering are needed less frequently.
3223 *
3224 * \note Application records are not affected by this option and
3225 * are currently always sent in separate datagrams.
3226 *
3227 */
3228 void mbedtls_ssl_set_datagram_packing(mbedtls_ssl_context *ssl,
3229 unsigned allow_packing);
3230
3231 /**
3232 * \brief Set retransmit timeout values for the DTLS handshake.
3233 * (DTLS only, no effect on TLS.)
3234 *
3235 * \param conf SSL configuration
3236 * \param min Initial timeout value in milliseconds.
3237 * Default: 1000 (1 second).
3238 * \param max Maximum timeout value in milliseconds.
3239 * Default: 60000 (60 seconds).
3240 *
3241 * \note Default values are from RFC 6347 section 4.2.4.1.
3242 *
3243 * \note The 'min' value should typically be slightly above the
3244 * expected round-trip time to your peer, plus whatever time
3245 * it takes for the peer to process the message. For example,
3246 * if your RTT is about 600ms and you peer needs up to 1s to
3247 * do the cryptographic operations in the handshake, then you
3248 * should set 'min' slightly above 1600. Lower values of 'min'
3249 * might cause spurious resends which waste network resources,
3250 * while larger value of 'min' will increase overall latency
3251 * on unreliable network links.
3252 *
3253 * \note The more unreliable your network connection is, the larger
3254 * your max / min ratio needs to be in order to achieve
3255 * reliable handshakes.
3256 *
3257 * \note Messages are retransmitted up to log2(ceil(max/min)) times.
3258 * For example, if min = 1s and max = 5s, the retransmit plan
3259 * goes: send ... 1s -> resend ... 2s -> resend ... 4s ->
3260 * resend ... 5s -> give up and return a timeout error.
3261 */
3262 void mbedtls_ssl_conf_handshake_timeout(mbedtls_ssl_config *conf, uint32_t min, uint32_t max);
3263 #endif /* MBEDTLS_SSL_PROTO_DTLS */
3264
3265 #if defined(MBEDTLS_SSL_SRV_C)
3266 /**
3267 * \brief Set the session cache callbacks (server-side only)
3268 * If not set, no session resuming is done (except if session
3269 * tickets are enabled too).
3270 *
3271 * The session cache has the responsibility to check for stale
3272 * entries based on timeout. See RFC 5246 for recommendations.
3273 *
3274 * Warning: session.peer_cert is cleared by the SSL/TLS layer on
3275 * connection shutdown, so do not cache the pointer! Either set
3276 * it to NULL or make a full copy of the certificate.
3277 *
3278 * The get callback is called once during the initial handshake
3279 * to enable session resuming. The get function has the
3280 * following parameters: (void *parameter, mbedtls_ssl_session *session)
3281 * If a valid entry is found, it should fill the master of
3282 * the session object with the cached values and return 0,
3283 * return 1 otherwise. Optionally peer_cert can be set as well
3284 * if it is properly present in cache entry.
3285 *
3286 * The set callback is called once during the initial handshake
3287 * to enable session resuming after the entire handshake has
3288 * been finished. The set function has the following parameters:
3289 * (void *parameter, const mbedtls_ssl_session *session). The function
3290 * should create a cache entry for future retrieval based on
3291 * the data in the session structure and should keep in mind
3292 * that the mbedtls_ssl_session object presented (and all its referenced
3293 * data) is cleared by the SSL/TLS layer when the connection is
3294 * terminated. It is recommended to add metadata to determine if
3295 * an entry is still valid in the future. Return 0 if
3296 * successfully cached, return 1 otherwise.
3297 *
3298 * \param conf SSL configuration
3299 * \param p_cache parameter (context) for both callbacks
3300 * \param f_get_cache session get callback
3301 * \param f_set_cache session set callback
3302 */
3303 void mbedtls_ssl_conf_session_cache(mbedtls_ssl_config *conf,
3304 void *p_cache,
3305 mbedtls_ssl_cache_get_t *f_get_cache,
3306 mbedtls_ssl_cache_set_t *f_set_cache);
3307 #endif /* MBEDTLS_SSL_SRV_C */
3308
3309 #if defined(MBEDTLS_SSL_CLI_C)
3310 /**
3311 * \brief Load a session for session resumption.
3312 *
3313 * Sessions loaded through this call will be considered
3314 * for session resumption in the next handshake.
3315 *
3316 * \note Even if this call succeeds, it is not guaranteed that
3317 * the next handshake will indeed be shortened through the
3318 * use of session resumption: The server is always free
3319 * to reject any attempt for resumption and fall back to
3320 * a full handshake.
3321 *
3322 * \note This function can handle a variety of mechanisms for session
3323 * resumption: For TLS 1.2, both session ID-based resumption
3324 * and ticket-based resumption will be considered. For TLS 1.3,
3325 * sessions equate to tickets, and loading one session by
3326 * calling this function will lead to its corresponding ticket
3327 * being advertised as resumption PSK by the client. This
3328 * depends on session tickets being enabled (see
3329 * #MBEDTLS_SSL_SESSION_TICKETS configuration option) though.
3330 * If session tickets are disabled, a call to this function
3331 * with a TLS 1.3 session, will not have any effect on the next
3332 * handshake for the SSL context \p ssl.
3333 *
3334 * \param ssl The SSL context representing the connection which should
3335 * be attempted to be setup using session resumption. This
3336 * must be initialized via mbedtls_ssl_init() and bound to
3337 * an SSL configuration via mbedtls_ssl_setup(), but
3338 * the handshake must not yet have been started.
3339 * \param session The session to be considered for session resumption.
3340 * This must be a session previously exported via
3341 * mbedtls_ssl_get_session(), and potentially serialized and
3342 * deserialized through mbedtls_ssl_session_save() and
3343 * mbedtls_ssl_session_load() in the meantime.
3344 *
3345 * \return \c 0 if successful.
3346 * \return \c MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if the session
3347 * could not be loaded because one session has already been
3348 * loaded. This error is non-fatal, and has no observable
3349 * effect on the SSL context or the session that was attempted
3350 * to be loaded.
3351 * \return Another negative error code on other kinds of failure.
3352 *
3353 * \sa mbedtls_ssl_get_session()
3354 * \sa mbedtls_ssl_session_load()
3355 */
3356 int mbedtls_ssl_set_session(mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session);
3357 #endif /* MBEDTLS_SSL_CLI_C */
3358
3359 /**
3360 * \brief Load serialized session data into a session structure.
3361 * On client, this can be used for loading saved sessions
3362 * before resuming them with mbedtls_ssl_set_session().
3363 * On server, this can be used for alternative implementations
3364 * of session cache or session tickets.
3365 *
3366 * \warning If a peer certificate chain is associated with the session,
3367 * the serialized state will only contain the peer's
3368 * end-entity certificate and the result of the chain
3369 * verification (unless verification was disabled), but not
3370 * the rest of the chain.
3371 *
3372 * \see mbedtls_ssl_session_save()
3373 * \see mbedtls_ssl_set_session()
3374 *
3375 * \param session The session structure to be populated. It must have been
3376 * initialised with mbedtls_ssl_session_init() but not
3377 * populated yet.
3378 * \param buf The buffer holding the serialized session data. It must be a
3379 * readable buffer of at least \p len bytes.
3380 * \param len The size of the serialized data in bytes.
3381 *
3382 * \return \c 0 if successful.
3383 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
3384 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
3385 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
3386 * was generated in a different version or configuration of
3387 * Mbed TLS.
3388 * \return Another negative value for other kinds of errors (for
3389 * example, unsupported features in the embedded certificate).
3390 */
3391 int mbedtls_ssl_session_load(mbedtls_ssl_session *session,
3392 const unsigned char *buf,
3393 size_t len);
3394
3395 /**
3396 * \brief Save session structure as serialized data in a buffer.
3397 * On client, this can be used for saving session data,
3398 * potentially in non-volatile storage, for resuming later.
3399 * On server, this can be used for alternative implementations
3400 * of session cache or session tickets.
3401 *
3402 * \see mbedtls_ssl_session_load()
3403 *
3404 * \param session The session structure to be saved.
3405 * \param buf The buffer to write the serialized data to. It must be a
3406 * writeable buffer of at least \p buf_len bytes, or may be \c
3407 * NULL if \p buf_len is \c 0.
3408 * \param buf_len The number of bytes available for writing in \p buf.
3409 * \param olen The size in bytes of the data that has been or would have
3410 * been written. It must point to a valid \c size_t.
3411 *
3412 * \note \p olen is updated to the correct value regardless of
3413 * whether \p buf_len was large enough. This makes it possible
3414 * to determine the necessary size by calling this function
3415 * with \p buf set to \c NULL and \p buf_len to \c 0.
3416 *
3417 * \note For TLS 1.3 sessions, this feature is supported only if the
3418 * MBEDTLS_SSL_SESSION_TICKETS configuration option is enabled,
3419 * as in TLS 1.3 session resumption is possible only with
3420 * tickets.
3421 *
3422 * \return \c 0 if successful.
3423 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
3424 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if the
3425 * MBEDTLS_SSL_SESSION_TICKETS configuration option is disabled
3426 * and the session is a TLS 1.3 session.
3427 */
3428 int mbedtls_ssl_session_save(const mbedtls_ssl_session *session,
3429 unsigned char *buf,
3430 size_t buf_len,
3431 size_t *olen);
3432
3433 /**
3434 * \brief Set the list of allowed ciphersuites and the preference
3435 * order. First in the list has the highest preference.
3436 *
3437 * For TLS 1.2, the notion of ciphersuite determines both
3438 * the key exchange mechanism and the suite of symmetric
3439 * algorithms to be used during and after the handshake.
3440 *
3441 * For TLS 1.3 (in development), the notion of ciphersuite
3442 * only determines the suite of symmetric algorithms to be
3443 * used during and after the handshake, while key exchange
3444 * mechanisms are configured separately.
3445 *
3446 * In Mbed TLS, ciphersuites for both TLS 1.2 and TLS 1.3
3447 * are configured via this function. For users of TLS 1.3,
3448 * there will be separate API for the configuration of key
3449 * exchange mechanisms.
3450 *
3451 * The list of ciphersuites passed to this function may
3452 * contain a mixture of TLS 1.2 and TLS 1.3 ciphersuite
3453 * identifiers. This is useful if negotiation of TLS 1.3
3454 * should be attempted, but a fallback to TLS 1.2 would
3455 * be tolerated.
3456 *
3457 * \note By default, the server chooses its preferred
3458 * ciphersuite among those that the client supports. If
3459 * mbedtls_ssl_conf_preference_order() is called to prefer
3460 * the client's preferences, the server instead chooses
3461 * the client's preferred ciphersuite among those that
3462 * the server supports.
3463 *
3464 * \warning The ciphersuites array \p ciphersuites is not copied.
3465 * It must remain valid for the lifetime of the SSL
3466 * configuration \p conf.
3467 *
3468 * \param conf The SSL configuration to modify.
3469 * \param ciphersuites A 0-terminated list of IANA identifiers of supported
3470 * ciphersuites, accessible through \c MBEDTLS_TLS_XXX
3471 * and \c MBEDTLS_TLS1_3_XXX macros defined in
3472 * ssl_ciphersuites.h.
3473 */
3474 void mbedtls_ssl_conf_ciphersuites(mbedtls_ssl_config *conf,
3475 const int *ciphersuites);
3476
3477 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
3478 /**
3479 * \brief Set the supported key exchange modes for TLS 1.3 connections.
3480 *
3481 * In contrast to TLS 1.2, the ciphersuite concept in TLS 1.3 does not
3482 * include the choice of key exchange mechanism. It is therefore not
3483 * covered by the API mbedtls_ssl_conf_ciphersuites(). See the
3484 * documentation of mbedtls_ssl_conf_ciphersuites() for more
3485 * information on the ciphersuite concept in TLS 1.2 and TLS 1.3.
3486 *
3487 * The present function is specific to TLS 1.3 and allows users to
3488 * configure the set of supported key exchange mechanisms in TLS 1.3.
3489 *
3490 * \param conf The SSL configuration the change should apply to.
3491 * \param kex_modes A bitwise combination of one or more of the following:
3492 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK
3493 * This flag enables pure-PSK key exchanges.
3494 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL
3495 * This flag enables combined PSK-ephemeral key exchanges.
3496 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL
3497 * This flag enables pure-ephemeral key exchanges.
3498 * For convenience, the following pre-defined macros are
3499 * available for combinations of the above:
3500 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_ALL
3501 * Includes all of pure-PSK, PSK-ephemeral and pure-ephemeral.
3502 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL
3503 * Includes both pure-PSK and combined PSK-ephemeral
3504 * key exchanges, but excludes pure-ephemeral key exchanges.
3505 * - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL
3506 * Includes both pure-ephemeral and combined PSK-ephemeral
3507 * key exchanges.
3508 *
3509 * \note If a PSK-based key exchange mode shall be supported, applications
3510 * must also use the APIs mbedtls_ssl_conf_psk() or
3511 * mbedtls_ssl_conf_psk_cb() or mbedtls_ssl_conf_psk_opaque()
3512 * to configure the PSKs to be used.
3513 *
3514 * \note If a pure-ephemeral key exchange mode shall be supported,
3515 * server-side applications must also provide a certificate via
3516 * mbedtls_ssl_conf_own_cert().
3517 *
3518 */
3519
3520 void mbedtls_ssl_conf_tls13_key_exchange_modes(mbedtls_ssl_config *conf,
3521 const int kex_modes);
3522 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
3523
3524 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
3525 #define MBEDTLS_SSL_UNEXPECTED_CID_IGNORE 0
3526 #define MBEDTLS_SSL_UNEXPECTED_CID_FAIL 1
3527 /**
3528 * \brief Specify the length of Connection IDs for incoming
3529 * encrypted DTLS records, as well as the behaviour
3530 * on unexpected CIDs.
3531 *
3532 * By default, the CID length is set to \c 0,
3533 * and unexpected CIDs are silently ignored.
3534 *
3535 * \param conf The SSL configuration to modify.
3536 * \param len The length in Bytes of the CID fields in encrypted
3537 * DTLS records using the CID mechanism. This must
3538 * not be larger than #MBEDTLS_SSL_CID_OUT_LEN_MAX.
3539 * \param ignore_other_cids This determines the stack's behaviour when
3540 * receiving a record with an unexpected CID.
3541 * Possible values are:
3542 * - #MBEDTLS_SSL_UNEXPECTED_CID_IGNORE
3543 * In this case, the record is silently ignored.
3544 * - #MBEDTLS_SSL_UNEXPECTED_CID_FAIL
3545 * In this case, the stack fails with the specific
3546 * error code #MBEDTLS_ERR_SSL_UNEXPECTED_CID.
3547 *
3548 * \note The CID specification allows implementations to either
3549 * use a common length for all incoming connection IDs or
3550 * allow variable-length incoming IDs. Mbed TLS currently
3551 * requires a common length for all connections sharing the
3552 * same SSL configuration; this allows simpler parsing of
3553 * record headers.
3554 *
3555 * \return \c 0 on success.
3556 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if \p len
3557 * is too large.
3558 */
3559 int mbedtls_ssl_conf_cid(mbedtls_ssl_config *conf, size_t len,
3560 int ignore_other_cids);
3561 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
3562
3563 #if defined(MBEDTLS_X509_CRT_PARSE_C)
3564 /**
3565 * \brief Set the X.509 security profile used for verification
3566 *
3567 * \note The restrictions are enforced for all certificates in the
3568 * chain. However, signatures in the handshake are not covered
3569 * by this setting but by \b mbedtls_ssl_conf_sig_hashes().
3570 *
3571 * \param conf SSL configuration
3572 * \param profile Profile to use
3573 */
3574 void mbedtls_ssl_conf_cert_profile(mbedtls_ssl_config *conf,
3575 const mbedtls_x509_crt_profile *profile);
3576
3577 /**
3578 * \brief Set the data required to verify peer certificate
3579 *
3580 * \note See \c mbedtls_x509_crt_verify() for notes regarding the
3581 * parameters ca_chain (maps to trust_ca for that function)
3582 * and ca_crl.
3583 *
3584 * \param conf SSL configuration
3585 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
3586 * \param ca_crl trusted CA CRLs
3587 */
3588 void mbedtls_ssl_conf_ca_chain(mbedtls_ssl_config *conf,
3589 mbedtls_x509_crt *ca_chain,
3590 mbedtls_x509_crl *ca_crl);
3591
3592 #if defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED)
3593 /**
3594 * \brief Set DN hints sent to client in CertificateRequest message
3595 *
3596 * \note If not set, subject distinguished names (DNs) are taken
3597 * from \c mbedtls_ssl_conf_ca_chain()
3598 * or \c mbedtls_ssl_set_hs_ca_chain())
3599 *
3600 * \param conf SSL configuration
3601 * \param crt crt chain whose subject DNs are issuer DNs of client certs
3602 * from which the client should select client peer certificate.
3603 */
3604 static inline
mbedtls_ssl_conf_dn_hints(mbedtls_ssl_config * conf,const mbedtls_x509_crt * crt)3605 void mbedtls_ssl_conf_dn_hints(mbedtls_ssl_config *conf,
3606 const mbedtls_x509_crt *crt)
3607 {
3608 conf->MBEDTLS_PRIVATE(dn_hints) = crt;
3609 }
3610 #endif /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */
3611
3612 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
3613 /**
3614 * \brief Set the trusted certificate callback.
3615 *
3616 * This API allows to register the set of trusted certificates
3617 * through a callback, instead of a linked list as configured
3618 * by mbedtls_ssl_conf_ca_chain().
3619 *
3620 * This is useful for example in contexts where a large number
3621 * of CAs are used, and the inefficiency of maintaining them
3622 * in a linked list cannot be tolerated. It is also useful when
3623 * the set of trusted CAs needs to be modified frequently.
3624 *
3625 * See the documentation of `mbedtls_x509_crt_ca_cb_t` for
3626 * more information.
3627 *
3628 * \param conf The SSL configuration to register the callback with.
3629 * \param f_ca_cb The trusted certificate callback to use when verifying
3630 * certificate chains.
3631 * \param p_ca_cb The context to be passed to \p f_ca_cb (for example,
3632 * a reference to a trusted CA database).
3633 *
3634 * \note This API is incompatible with mbedtls_ssl_conf_ca_chain():
3635 * Any call to this function overwrites the values set through
3636 * earlier calls to mbedtls_ssl_conf_ca_chain() or
3637 * mbedtls_ssl_conf_ca_cb().
3638 *
3639 * \note This API is incompatible with CA indication in
3640 * CertificateRequest messages: A server-side SSL context which
3641 * is bound to an SSL configuration that uses a CA callback
3642 * configured via mbedtls_ssl_conf_ca_cb(), and which requires
3643 * client authentication, will send an empty CA list in the
3644 * corresponding CertificateRequest message.
3645 *
3646 * \note This API is incompatible with mbedtls_ssl_set_hs_ca_chain():
3647 * If an SSL context is bound to an SSL configuration which uses
3648 * CA callbacks configured via mbedtls_ssl_conf_ca_cb(), then
3649 * calls to mbedtls_ssl_set_hs_ca_chain() have no effect.
3650 *
3651 * \note The use of this API disables the use of restartable ECC
3652 * during X.509 CRT signature verification (but doesn't affect
3653 * other uses).
3654 *
3655 * \warning This API is incompatible with the use of CRLs. Any call to
3656 * mbedtls_ssl_conf_ca_cb() unsets CRLs configured through
3657 * earlier calls to mbedtls_ssl_conf_ca_chain().
3658 *
3659 * \warning In multi-threaded environments, the callback \p f_ca_cb
3660 * must be thread-safe, and it is the user's responsibility
3661 * to guarantee this (for example through a mutex
3662 * contained in the callback context pointed to by \p p_ca_cb).
3663 */
3664 void mbedtls_ssl_conf_ca_cb(mbedtls_ssl_config *conf,
3665 mbedtls_x509_crt_ca_cb_t f_ca_cb,
3666 void *p_ca_cb);
3667 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
3668
3669 /**
3670 * \brief Set own certificate chain and private key
3671 *
3672 * \note own_cert should contain in order from the bottom up your
3673 * certificate chain. The top certificate (self-signed)
3674 * can be omitted.
3675 *
3676 * \note On server, this function can be called multiple times to
3677 * provision more than one cert/key pair (eg one ECDSA, one
3678 * RSA with SHA-256, one RSA with SHA-1). An adequate
3679 * certificate will be selected according to the client's
3680 * advertised capabilities. In case multiple certificates are
3681 * adequate, preference is given to the one set by the first
3682 * call to this function, then second, etc.
3683 *
3684 * \note On client, only the first call has any effect. That is,
3685 * only one client certificate can be provisioned. The
3686 * server's preferences in its CertificateRequest message will
3687 * be ignored and our only cert will be sent regardless of
3688 * whether it matches those preferences - the server can then
3689 * decide what it wants to do with it.
3690 *
3691 * \note The provided \p pk_key needs to match the public key in the
3692 * first certificate in \p own_cert, or all handshakes using
3693 * that certificate will fail. It is your responsibility
3694 * to ensure that; this function will not perform any check.
3695 * You may use mbedtls_pk_check_pair() in order to perform
3696 * this check yourself, but be aware that this function can
3697 * be computationally expensive on some key types.
3698 *
3699 * \param conf SSL configuration
3700 * \param own_cert own public certificate chain
3701 * \param pk_key own private key
3702 *
3703 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
3704 */
3705 int mbedtls_ssl_conf_own_cert(mbedtls_ssl_config *conf,
3706 mbedtls_x509_crt *own_cert,
3707 mbedtls_pk_context *pk_key);
3708 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3709
3710 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED)
3711 /**
3712 * \brief Configure pre-shared keys (PSKs) and their
3713 * identities to be used in PSK-based ciphersuites.
3714 *
3715 * Only one PSK can be registered, through either
3716 * mbedtls_ssl_conf_psk() or mbedtls_ssl_conf_psk_opaque().
3717 * If you attempt to register more than one PSK, this function
3718 * fails, though this may change in future versions, which
3719 * may add support for multiple PSKs.
3720 *
3721 * \note This is mainly useful for clients. Servers will usually
3722 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
3723 *
3724 * \note A PSK set by \c mbedtls_ssl_set_hs_psk() in the PSK callback
3725 * takes precedence over a PSK configured by this function.
3726 *
3727 * \param conf The SSL configuration to register the PSK with.
3728 * \param psk The pointer to the pre-shared key to use.
3729 * \param psk_len The length of the pre-shared key in bytes.
3730 * \param psk_identity The pointer to the pre-shared key identity.
3731 * \param psk_identity_len The length of the pre-shared key identity
3732 * in bytes.
3733 *
3734 * \note The PSK and its identity are copied internally and
3735 * hence need not be preserved by the caller for the lifetime
3736 * of the SSL configuration.
3737 *
3738 * \return \c 0 if successful.
3739 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no more PSKs
3740 * can be configured. In this case, the old PSK(s) remain intact.
3741 * \return Another negative error code on other kinds of failure.
3742 */
3743 int mbedtls_ssl_conf_psk(mbedtls_ssl_config *conf,
3744 const unsigned char *psk, size_t psk_len,
3745 const unsigned char *psk_identity, size_t psk_identity_len);
3746
3747 #if defined(MBEDTLS_USE_PSA_CRYPTO)
3748 /**
3749 * \brief Configure one or more opaque pre-shared keys (PSKs) and
3750 * their identities to be used in PSK-based ciphersuites.
3751 *
3752 * Only one PSK can be registered, through either
3753 * mbedtls_ssl_conf_psk() or mbedtls_ssl_conf_psk_opaque().
3754 * If you attempt to register more than one PSK, this function
3755 * fails, though this may change in future versions, which
3756 * may add support for multiple PSKs.
3757 *
3758 * \note This is mainly useful for clients. Servers will usually
3759 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
3760 *
3761 * \note An opaque PSK set by \c mbedtls_ssl_set_hs_psk_opaque() in
3762 * the PSK callback takes precedence over an opaque PSK
3763 * configured by this function.
3764 *
3765 * \param conf The SSL configuration to register the PSK with.
3766 * \param psk The identifier of the key slot holding the PSK.
3767 * Until \p conf is destroyed or this function is successfully
3768 * called again, the key slot \p psk must be populated with a
3769 * key of type PSA_ALG_CATEGORY_KEY_DERIVATION whose policy
3770 * allows its use for the key derivation algorithm applied
3771 * in the handshake.
3772 * \param psk_identity The pointer to the pre-shared key identity.
3773 * \param psk_identity_len The length of the pre-shared key identity
3774 * in bytes.
3775 *
3776 * \note The PSK identity hint is copied internally and hence need
3777 * not be preserved by the caller for the lifetime of the
3778 * SSL configuration.
3779 *
3780 * \return \c 0 if successful.
3781 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no more PSKs
3782 * can be configured. In this case, the old PSK(s) remain intact.
3783 * \return Another negative error code on other kinds of failure.
3784 */
3785 int mbedtls_ssl_conf_psk_opaque(mbedtls_ssl_config *conf,
3786 mbedtls_svc_key_id_t psk,
3787 const unsigned char *psk_identity,
3788 size_t psk_identity_len);
3789 #endif /* MBEDTLS_USE_PSA_CRYPTO */
3790
3791 /**
3792 * \brief Set the pre-shared Key (PSK) for the current handshake.
3793 *
3794 * \note This should only be called inside the PSK callback,
3795 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
3796 *
3797 * \note A PSK set by this function takes precedence over a PSK
3798 * configured by \c mbedtls_ssl_conf_psk().
3799 *
3800 * \param ssl The SSL context to configure a PSK for.
3801 * \param psk The pointer to the pre-shared key.
3802 * \param psk_len The length of the pre-shared key in bytes.
3803 *
3804 * \return \c 0 if successful.
3805 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
3806 */
3807 int mbedtls_ssl_set_hs_psk(mbedtls_ssl_context *ssl,
3808 const unsigned char *psk, size_t psk_len);
3809
3810 #if defined(MBEDTLS_USE_PSA_CRYPTO)
3811 /**
3812 * \brief Set an opaque pre-shared Key (PSK) for the current handshake.
3813 *
3814 * \note This should only be called inside the PSK callback,
3815 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
3816 *
3817 * \note An opaque PSK set by this function takes precedence over an
3818 * opaque PSK configured by \c mbedtls_ssl_conf_psk_opaque().
3819 *
3820 * \param ssl The SSL context to configure a PSK for.
3821 * \param psk The identifier of the key slot holding the PSK.
3822 * For the duration of the current handshake, the key slot
3823 * must be populated with a key of type
3824 * PSA_ALG_CATEGORY_KEY_DERIVATION whose policy allows its
3825 * use for the key derivation algorithm
3826 * applied in the handshake.
3827 *
3828 * \return \c 0 if successful.
3829 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
3830 */
3831 int mbedtls_ssl_set_hs_psk_opaque(mbedtls_ssl_context *ssl,
3832 mbedtls_svc_key_id_t psk);
3833 #endif /* MBEDTLS_USE_PSA_CRYPTO */
3834
3835 #if defined(MBEDTLS_SSL_SRV_C)
3836 /**
3837 * \brief Set the PSK callback (server-side only).
3838 *
3839 * If set, the PSK callback is called for each
3840 * handshake where a PSK-based ciphersuite was negotiated.
3841 * The caller provides the identity received and wants to
3842 * receive the actual PSK data and length.
3843 *
3844 * The callback has the following parameters:
3845 * - \c void*: The opaque pointer \p p_psk.
3846 * - \c mbedtls_ssl_context*: The SSL context to which
3847 * the operation applies.
3848 * - \c const unsigned char*: The PSK identity
3849 * selected by the client.
3850 * - \c size_t: The length of the PSK identity
3851 * selected by the client.
3852 *
3853 * If a valid PSK identity is found, the callback should use
3854 * \c mbedtls_ssl_set_hs_psk() or
3855 * \c mbedtls_ssl_set_hs_psk_opaque()
3856 * on the SSL context to set the correct PSK and return \c 0.
3857 * Any other return value will result in a denied PSK identity.
3858 *
3859 * \note A dynamic PSK (i.e. set by the PSK callback) takes
3860 * precedence over a static PSK (i.e. set by
3861 * \c mbedtls_ssl_conf_psk() or
3862 * \c mbedtls_ssl_conf_psk_opaque()).
3863 * This means that if you set a PSK callback using this
3864 * function, you don't need to set a PSK using
3865 * \c mbedtls_ssl_conf_psk() or
3866 * \c mbedtls_ssl_conf_psk_opaque()).
3867 *
3868 * \param conf The SSL configuration to register the callback with.
3869 * \param f_psk The callback for selecting and setting the PSK based
3870 * in the PSK identity chosen by the client.
3871 * \param p_psk A pointer to an opaque structure to be passed to
3872 * the callback, for example a PSK store.
3873 */
3874 void mbedtls_ssl_conf_psk_cb(mbedtls_ssl_config *conf,
3875 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *,
3876 size_t),
3877 void *p_psk);
3878 #endif /* MBEDTLS_SSL_SRV_C */
3879 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED */
3880
3881 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
3882 /**
3883 * \brief Set the Diffie-Hellman public P and G values
3884 * from big-endian binary presentations.
3885 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN)
3886 *
3887 * \param conf SSL configuration
3888 * \param dhm_P Diffie-Hellman-Merkle modulus in big-endian binary form
3889 * \param P_len Length of DHM modulus
3890 * \param dhm_G Diffie-Hellman-Merkle generator in big-endian binary form
3891 * \param G_len Length of DHM generator
3892 *
3893 * \return 0 if successful
3894 */
3895 int mbedtls_ssl_conf_dh_param_bin(mbedtls_ssl_config *conf,
3896 const unsigned char *dhm_P, size_t P_len,
3897 const unsigned char *dhm_G, size_t G_len);
3898
3899 /**
3900 * \brief Set the Diffie-Hellman public P and G values,
3901 * read from existing context (server-side only)
3902 *
3903 * \param conf SSL configuration
3904 * \param dhm_ctx Diffie-Hellman-Merkle context
3905 *
3906 * \return 0 if successful
3907 */
3908 int mbedtls_ssl_conf_dh_param_ctx(mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx);
3909 #endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */
3910
3911 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
3912 /**
3913 * \brief Set the minimum length for Diffie-Hellman parameters.
3914 * (Client-side only.)
3915 * (Default: 1024 bits.)
3916 *
3917 * \param conf SSL configuration
3918 * \param bitlen Minimum bit length of the DHM prime
3919 */
3920 void mbedtls_ssl_conf_dhm_min_bitlen(mbedtls_ssl_config *conf,
3921 unsigned int bitlen);
3922 #endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */
3923
3924 #if defined(MBEDTLS_ECP_C)
3925 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
3926 /**
3927 * \brief Set the allowed curves in order of preference.
3928 *
3929 * On server: this only affects selection of the ECDHE curve;
3930 * the curves used for ECDH and ECDSA are determined by the
3931 * list of available certificates instead.
3932 *
3933 * On client: this affects the list of curves offered for any
3934 * use. The server can override our preference order.
3935 *
3936 * Both sides: limits the set of curves accepted for use in
3937 * ECDHE and in the peer's end-entity certificate.
3938 *
3939 * \deprecated Superseded by mbedtls_ssl_conf_groups().
3940 *
3941 * \note This has no influence on which curves are allowed inside the
3942 * certificate chains, see \c mbedtls_ssl_conf_cert_profile()
3943 * for that. For the end-entity certificate however, the key
3944 * will be accepted only if it is allowed both by this list
3945 * and by the cert profile.
3946 *
3947 * \note This list should be ordered by decreasing preference
3948 * (preferred curve first).
3949 *
3950 * \note The default list is the same set of curves that
3951 * #mbedtls_x509_crt_profile_default allows, plus
3952 * ECDHE-only curves selected according to the same criteria.
3953 * The order favors curves with the lowest resource usage.
3954 *
3955 * \note New minor versions of Mbed TLS may extend this list,
3956 * for example if new curves are added to the library.
3957 * New minor versions of Mbed TLS will not remove items
3958 * from this list unless serious security concerns require it.
3959 * New minor versions of Mbed TLS may change the order in
3960 * keeping with the general principle of favoring the lowest
3961 * resource usage.
3962 *
3963 * \param conf SSL configuration
3964 * \param curves Ordered list of allowed curves,
3965 * terminated by MBEDTLS_ECP_DP_NONE.
3966 */
3967 void MBEDTLS_DEPRECATED mbedtls_ssl_conf_curves(mbedtls_ssl_config *conf,
3968 const mbedtls_ecp_group_id *curves);
3969 #endif /* MBEDTLS_DEPRECATED_REMOVED */
3970 #endif /* MBEDTLS_ECP_C */
3971
3972 /**
3973 * \brief Set the allowed groups in order of preference.
3974 *
3975 * On server: This only affects the choice of key agreement mechanism
3976 *
3977 * On client: this affects the list of groups offered for any
3978 * use. The server can override our preference order.
3979 *
3980 * Both sides: limits the set of groups accepted for use in
3981 * key sharing.
3982 *
3983 * \note This function replaces the deprecated mbedtls_ssl_conf_curves(),
3984 * which only allows ECP curves to be configured.
3985 *
3986 * \note The most recent invocation of either mbedtls_ssl_conf_curves()
3987 * or mbedtls_ssl_conf_groups() nullifies all previous invocations
3988 * of both.
3989 *
3990 * \note This list should be ordered by decreasing preference
3991 * (preferred group first).
3992 *
3993 * \note When this function is not called, a default list is used,
3994 * consisting of all supported curves at 255 bits and above,
3995 * and all supported finite fields at 2048 bits and above.
3996 * The order favors groups with the lowest resource usage.
3997 *
3998 * \note New minor versions of Mbed TLS will not remove items
3999 * from the default list unless serious security concerns require it.
4000 * New minor versions of Mbed TLS may change the order in
4001 * keeping with the general principle of favoring the lowest
4002 * resource usage.
4003 *
4004 * \param conf SSL configuration
4005 * \param groups List of allowed groups ordered by preference, terminated by 0.
4006 * Must contain valid IANA NamedGroup IDs (provided via either an integer
4007 * or using MBEDTLS_TLS1_3_NAMED_GROUP_XXX macros).
4008 */
4009 void mbedtls_ssl_conf_groups(mbedtls_ssl_config *conf,
4010 const uint16_t *groups);
4011
4012 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
4013 #if !defined(MBEDTLS_DEPRECATED_REMOVED) && defined(MBEDTLS_SSL_PROTO_TLS1_2)
4014 /**
4015 * \brief Set the allowed hashes for signatures during the handshake.
4016 *
4017 * \note This only affects which hashes are offered and can be used
4018 * for signatures during the handshake. Hashes for message
4019 * authentication and the TLS PRF are controlled by the
4020 * ciphersuite, see \c mbedtls_ssl_conf_ciphersuites(). Hashes
4021 * used for certificate signature are controlled by the
4022 * verification profile, see \c mbedtls_ssl_conf_cert_profile().
4023 *
4024 * \deprecated Superseded by mbedtls_ssl_conf_sig_algs().
4025 *
4026 * \note This list should be ordered by decreasing preference
4027 * (preferred hash first).
4028 *
4029 * \note By default, all supported hashes whose length is at least
4030 * 256 bits are allowed. This is the same set as the default
4031 * for certificate verification
4032 * (#mbedtls_x509_crt_profile_default).
4033 * The preference order is currently unspecified and may
4034 * change in future versions.
4035 *
4036 * \note New minor versions of Mbed TLS may extend this list,
4037 * for example if new curves are added to the library.
4038 * New minor versions of Mbed TLS will not remove items
4039 * from this list unless serious security concerns require it.
4040 *
4041 * \param conf SSL configuration
4042 * \param hashes Ordered list of allowed signature hashes,
4043 * terminated by \c MBEDTLS_MD_NONE.
4044 */
4045 void MBEDTLS_DEPRECATED mbedtls_ssl_conf_sig_hashes(mbedtls_ssl_config *conf,
4046 const int *hashes);
4047 #endif /* !MBEDTLS_DEPRECATED_REMOVED && MBEDTLS_SSL_PROTO_TLS1_2 */
4048
4049 /**
4050 * \brief Configure allowed signature algorithms for use in TLS
4051 *
4052 * \param conf The SSL configuration to use.
4053 * \param sig_algs List of allowed IANA values for TLS 1.3 signature algorithms,
4054 * terminated by #MBEDTLS_TLS1_3_SIG_NONE. The list must remain
4055 * available throughout the lifetime of the conf object.
4056 * - For TLS 1.3, values of \c MBEDTLS_TLS1_3_SIG_XXXX should be
4057 * used.
4058 * - For TLS 1.2, values should be given as
4059 * "(HashAlgorithm << 8) | SignatureAlgorithm".
4060 */
4061 void mbedtls_ssl_conf_sig_algs(mbedtls_ssl_config *conf,
4062 const uint16_t *sig_algs);
4063 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
4064
4065 #if defined(MBEDTLS_X509_CRT_PARSE_C)
4066 /**
4067 * \brief Set or reset the hostname to check against the received
4068 * peer certificate. On a client, this also sets the
4069 * ServerName TLS extension, if that extension is enabled.
4070 * On a TLS 1.3 client, this also sets the server name in
4071 * the session resumption ticket, if that feature is enabled.
4072 *
4073 * \param ssl SSL context
4074 * \param hostname The server hostname. This may be \c NULL to clear
4075 * the hostname.
4076 *
4077 * \note Maximum hostname length #MBEDTLS_SSL_MAX_HOST_NAME_LEN.
4078 *
4079 * \note If the hostname is \c NULL on a client, then the server
4080 * is not authenticated: it only needs to have a valid
4081 * certificate, not a certificate matching its name.
4082 * Therefore you should always call this function on a client,
4083 * unless the connection is set up to only allow
4084 * pre-shared keys, or in scenarios where server
4085 * impersonation is not a concern. See the documentation of
4086 * #MBEDTLS_ERR_SSL_CERTIFICATE_VERIFICATION_WITHOUT_HOSTNAME
4087 * for more details.
4088 *
4089 * \return 0 if successful, #MBEDTLS_ERR_SSL_ALLOC_FAILED on
4090 * allocation failure, #MBEDTLS_ERR_SSL_BAD_INPUT_DATA on
4091 * too long input hostname.
4092 *
4093 * Hostname set to the one provided on success (cleared
4094 * when NULL). On allocation failure hostname is cleared.
4095 * On too long input failure, old hostname is unchanged.
4096 */
4097 int mbedtls_ssl_set_hostname(mbedtls_ssl_context *ssl, const char *hostname);
4098
4099 /**
4100 * \brief Get the hostname that checked against the received
4101 * server certificate. It is used to set the ServerName
4102 * TLS extension, too, if that extension is enabled.
4103 * (client-side only)
4104 *
4105 * \param ssl SSL context
4106 *
4107 * \return const pointer to the hostname value
4108 */
mbedtls_ssl_get_hostname(mbedtls_ssl_context * ssl)4109 static inline const char *mbedtls_ssl_get_hostname(mbedtls_ssl_context *ssl)
4110 {
4111 return ssl->MBEDTLS_PRIVATE(hostname);
4112 }
4113 #endif /* MBEDTLS_X509_CRT_PARSE_C */
4114
4115 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
4116 /**
4117 * \brief Retrieve SNI extension value for the current handshake.
4118 * Available in \c f_cert_cb of \c mbedtls_ssl_conf_cert_cb(),
4119 * this is the same value passed to \c f_sni callback of
4120 * \c mbedtls_ssl_conf_sni() and may be used instead of
4121 * \c mbedtls_ssl_conf_sni().
4122 *
4123 * \param ssl SSL context
4124 * \param name_len pointer into which to store length of returned value.
4125 * 0 if SNI extension is not present or not yet processed.
4126 *
4127 * \return const pointer to SNI extension value.
4128 * - value is valid only when called in \c f_cert_cb
4129 * registered with \c mbedtls_ssl_conf_cert_cb().
4130 * - value is NULL if SNI extension is not present.
4131 * - value is not '\0'-terminated. Use \c name_len for len.
4132 * - value must not be freed.
4133 */
4134 const unsigned char *mbedtls_ssl_get_hs_sni(mbedtls_ssl_context *ssl,
4135 size_t *name_len);
4136
4137 /**
4138 * \brief Set own certificate and key for the current handshake
4139 *
4140 * \note Same as \c mbedtls_ssl_conf_own_cert() but for use within
4141 * the SNI callback or the certificate selection callback.
4142 *
4143 * \note Passing null \c own_cert clears the certificate list for
4144 * the current handshake.
4145 *
4146 * \param ssl SSL context
4147 * \param own_cert own public certificate chain
4148 * \param pk_key own private key
4149 *
4150 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
4151 */
4152 int mbedtls_ssl_set_hs_own_cert(mbedtls_ssl_context *ssl,
4153 mbedtls_x509_crt *own_cert,
4154 mbedtls_pk_context *pk_key);
4155
4156 /**
4157 * \brief Set the data required to verify peer certificate for the
4158 * current handshake
4159 *
4160 * \note Same as \c mbedtls_ssl_conf_ca_chain() but for use within
4161 * the SNI callback or the certificate selection callback.
4162 *
4163 * \param ssl SSL context
4164 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
4165 * \param ca_crl trusted CA CRLs
4166 */
4167 void mbedtls_ssl_set_hs_ca_chain(mbedtls_ssl_context *ssl,
4168 mbedtls_x509_crt *ca_chain,
4169 mbedtls_x509_crl *ca_crl);
4170
4171 #if defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED)
4172 /**
4173 * \brief Set DN hints sent to client in CertificateRequest message
4174 *
4175 * \note Same as \c mbedtls_ssl_conf_dn_hints() but for use within
4176 * the SNI callback or the certificate selection callback.
4177 *
4178 * \param ssl SSL context
4179 * \param crt crt chain whose subject DNs are issuer DNs of client certs
4180 * from which the client should select client peer certificate.
4181 */
4182 void mbedtls_ssl_set_hs_dn_hints(mbedtls_ssl_context *ssl,
4183 const mbedtls_x509_crt *crt);
4184 #endif /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */
4185
4186 /**
4187 * \brief Set authmode for the current handshake.
4188 *
4189 * \note Same as \c mbedtls_ssl_conf_authmode() but for use within
4190 * the SNI callback or the certificate selection callback.
4191 *
4192 * \param ssl SSL context
4193 * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or
4194 * MBEDTLS_SSL_VERIFY_REQUIRED
4195 */
4196 void mbedtls_ssl_set_hs_authmode(mbedtls_ssl_context *ssl,
4197 int authmode);
4198
4199 /**
4200 * \brief Set server side ServerName TLS extension callback
4201 * (optional, server-side only).
4202 *
4203 * If set, the ServerName callback is called whenever the
4204 * server receives a ServerName TLS extension from the client
4205 * during a handshake. The ServerName callback has the
4206 * following parameters: (void *parameter, mbedtls_ssl_context *ssl,
4207 * const unsigned char *hostname, size_t len). If a suitable
4208 * certificate is found, the callback must set the
4209 * certificate(s) and key(s) to use with \c
4210 * mbedtls_ssl_set_hs_own_cert() (can be called repeatedly),
4211 * and may optionally adjust the CA and associated CRL with \c
4212 * mbedtls_ssl_set_hs_ca_chain() as well as the client
4213 * authentication mode with \c mbedtls_ssl_set_hs_authmode(),
4214 * then must return 0. If no matching name is found, the
4215 * callback may return non-zero to abort the handshake.
4216 *
4217 * \param conf SSL configuration
4218 * \param f_sni verification function
4219 * \param p_sni verification parameter
4220 */
4221 void mbedtls_ssl_conf_sni(mbedtls_ssl_config *conf,
4222 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *,
4223 size_t),
4224 void *p_sni);
4225 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
4226
4227 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
4228 /**
4229 * \brief Set the EC J-PAKE password for current handshake.
4230 *
4231 * \note An internal copy is made, and destroyed as soon as the
4232 * handshake is completed, or when the SSL context is reset or
4233 * freed.
4234 *
4235 * \note The SSL context needs to be already set up. The right place
4236 * to call this function is between \c mbedtls_ssl_setup() or
4237 * \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake().
4238 * Password cannot be empty (see RFC 8236).
4239 *
4240 * \param ssl SSL context
4241 * \param pw EC J-PAKE password (pre-shared secret). It cannot be empty
4242 * \param pw_len length of pw in bytes
4243 *
4244 * \return 0 on success, or a negative error code.
4245 */
4246 int mbedtls_ssl_set_hs_ecjpake_password(mbedtls_ssl_context *ssl,
4247 const unsigned char *pw,
4248 size_t pw_len);
4249
4250 /**
4251 * \brief Set the EC J-PAKE opaque password for current handshake.
4252 *
4253 * \note The key must remain valid until the handshake is over.
4254 *
4255 * \note The SSL context needs to be already set up. The right place
4256 * to call this function is between \c mbedtls_ssl_setup() or
4257 * \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake().
4258 *
4259 * \param ssl SSL context
4260 * \param pwd EC J-PAKE opaque password
4261 *
4262 * \return 0 on success, or a negative error code.
4263 */
4264 int mbedtls_ssl_set_hs_ecjpake_password_opaque(mbedtls_ssl_context *ssl,
4265 mbedtls_svc_key_id_t pwd);
4266 #endif /*MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
4267
4268 #if defined(MBEDTLS_SSL_ALPN)
4269 /**
4270 * \brief Set the supported Application Layer Protocols.
4271 *
4272 * \param conf SSL configuration
4273 * \param protos Pointer to a NULL-terminated list of supported protocols,
4274 * in decreasing preference order. The pointer to the list is
4275 * recorded by the library for later reference as required, so
4276 * the lifetime of the table must be at least as long as the
4277 * lifetime of the SSL configuration structure.
4278 *
4279 * \return 0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA.
4280 */
4281 int mbedtls_ssl_conf_alpn_protocols(mbedtls_ssl_config *conf, const char **protos);
4282
4283 /**
4284 * \brief Get the name of the negotiated Application Layer Protocol.
4285 * This function should be called after the handshake is
4286 * completed.
4287 *
4288 * \param ssl SSL context
4289 *
4290 * \return Protocol name, or NULL if no protocol was negotiated.
4291 */
4292 const char *mbedtls_ssl_get_alpn_protocol(const mbedtls_ssl_context *ssl);
4293 #endif /* MBEDTLS_SSL_ALPN */
4294
4295 #if defined(MBEDTLS_SSL_DTLS_SRTP)
4296 #if defined(MBEDTLS_DEBUG_C)
mbedtls_ssl_get_srtp_profile_as_string(mbedtls_ssl_srtp_profile profile)4297 static inline const char *mbedtls_ssl_get_srtp_profile_as_string(mbedtls_ssl_srtp_profile profile)
4298 {
4299 switch (profile) {
4300 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80:
4301 return "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80";
4302 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32:
4303 return "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32";
4304 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80:
4305 return "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80";
4306 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32:
4307 return "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32";
4308 default: break;
4309 }
4310 return "";
4311 }
4312 #endif /* MBEDTLS_DEBUG_C */
4313 /**
4314 * \brief Manage support for mki(master key id) value
4315 * in use_srtp extension.
4316 * MKI is an optional part of SRTP used for key management
4317 * and re-keying. See RFC3711 section 3.1 for details.
4318 * The default value is
4319 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED.
4320 *
4321 * \param conf The SSL configuration to manage mki support.
4322 * \param support_mki_value Enable or disable mki usage. Values are
4323 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED
4324 * or #MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED.
4325 */
4326 void mbedtls_ssl_conf_srtp_mki_value_supported(mbedtls_ssl_config *conf,
4327 int support_mki_value);
4328
4329 /**
4330 * \brief Set the supported DTLS-SRTP protection profiles.
4331 *
4332 * \param conf SSL configuration
4333 * \param profiles Pointer to a List of MBEDTLS_TLS_SRTP_UNSET terminated
4334 * supported protection profiles
4335 * in decreasing preference order.
4336 * The pointer to the list is recorded by the library
4337 * for later reference as required, so the lifetime
4338 * of the table must be at least as long as the lifetime
4339 * of the SSL configuration structure.
4340 * The list must not hold more than
4341 * MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH elements
4342 * (excluding the terminating MBEDTLS_TLS_SRTP_UNSET).
4343 *
4344 * \return 0 on success
4345 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA when the list of
4346 * protection profiles is incorrect.
4347 */
4348 int mbedtls_ssl_conf_dtls_srtp_protection_profiles
4349 (mbedtls_ssl_config *conf,
4350 const mbedtls_ssl_srtp_profile *profiles);
4351
4352 /**
4353 * \brief Set the mki_value for the current DTLS-SRTP session.
4354 *
4355 * \param ssl SSL context to use.
4356 * \param mki_value The MKI value to set.
4357 * \param mki_len The length of the MKI value.
4358 *
4359 * \note This function is relevant on client side only.
4360 * The server discovers the mki value during handshake.
4361 * A mki value set on server side using this function
4362 * is ignored.
4363 *
4364 * \return 0 on success
4365 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA
4366 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE
4367 */
4368 int mbedtls_ssl_dtls_srtp_set_mki_value(mbedtls_ssl_context *ssl,
4369 unsigned char *mki_value,
4370 uint16_t mki_len);
4371 /**
4372 * \brief Get the negotiated DTLS-SRTP information:
4373 * Protection profile and MKI value.
4374 *
4375 * \warning This function must be called after the handshake is
4376 * completed. The value returned by this function must
4377 * not be trusted or acted upon before the handshake completes.
4378 *
4379 * \param ssl The SSL context to query.
4380 * \param dtls_srtp_info The negotiated DTLS-SRTP information:
4381 * - Protection profile in use.
4382 * A direct mapping of the iana defined value for protection
4383 * profile on an uint16_t.
4384 http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
4385 * #MBEDTLS_TLS_SRTP_UNSET if the use of SRTP was not negotiated
4386 * or peer's Hello packet was not parsed yet.
4387 * - mki size and value( if size is > 0 ).
4388 */
4389 void mbedtls_ssl_get_dtls_srtp_negotiation_result(const mbedtls_ssl_context *ssl,
4390 mbedtls_dtls_srtp_info *dtls_srtp_info);
4391 #endif /* MBEDTLS_SSL_DTLS_SRTP */
4392
4393 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
4394 /**
4395 * \brief Set the maximum supported version sent from the client side
4396 * and/or accepted at the server side.
4397 *
4398 * See also the documentation of mbedtls_ssl_conf_min_version().
4399 *
4400 * \note This ignores ciphersuites from higher versions.
4401 *
4402 * \note This function is deprecated and has been replaced by
4403 * \c mbedtls_ssl_conf_max_tls_version().
4404 *
4405 * \param conf SSL configuration
4406 * \param major Major version number (#MBEDTLS_SSL_MAJOR_VERSION_3)
4407 * \param minor Minor version number
4408 * (#MBEDTLS_SSL_MINOR_VERSION_3 for (D)TLS 1.2,
4409 * #MBEDTLS_SSL_MINOR_VERSION_4 for TLS 1.3)
4410 */
4411 void MBEDTLS_DEPRECATED mbedtls_ssl_conf_max_version(mbedtls_ssl_config *conf, int major,
4412 int minor);
4413 #endif /* MBEDTLS_DEPRECATED_REMOVED */
4414
4415 /**
4416 * \brief Set the maximum supported version sent from the client side
4417 * and/or accepted at the server side.
4418 *
4419 * \note After the handshake, you can call
4420 * mbedtls_ssl_get_version_number() to see what version was
4421 * negotiated.
4422 *
4423 * \param conf SSL configuration
4424 * \param tls_version TLS protocol version number (\c mbedtls_ssl_protocol_version)
4425 * (#MBEDTLS_SSL_VERSION_UNKNOWN is not valid)
4426 */
mbedtls_ssl_conf_max_tls_version(mbedtls_ssl_config * conf,mbedtls_ssl_protocol_version tls_version)4427 static inline void mbedtls_ssl_conf_max_tls_version(mbedtls_ssl_config *conf,
4428 mbedtls_ssl_protocol_version tls_version)
4429 {
4430 conf->MBEDTLS_PRIVATE(max_tls_version) = tls_version;
4431 }
4432
4433 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
4434 /**
4435 * \brief Set the minimum accepted SSL/TLS protocol version
4436 *
4437 * \note By default, all supported versions are accepted.
4438 * Future versions of the library may disable older
4439 * protocol versions by default if they become deprecated.
4440 *
4441 * \note The following versions are supported (if enabled at
4442 * compile time):
4443 * - (D)TLS 1.2: \p major = #MBEDTLS_SSL_MAJOR_VERSION_3,
4444 * \p minor = #MBEDTLS_SSL_MINOR_VERSION_3
4445 * - TLS 1.3: \p major = #MBEDTLS_SSL_MAJOR_VERSION_3,
4446 * \p minor = #MBEDTLS_SSL_MINOR_VERSION_4
4447 *
4448 * Note that the numbers in the constant names are the
4449 * TLS internal protocol numbers, and the minor versions
4450 * differ by one from the human-readable versions!
4451 *
4452 * \note Input outside of the SSL_MAX_XXXXX_VERSION and
4453 * SSL_MIN_XXXXX_VERSION range is ignored.
4454 *
4455 * \note After the handshake, you can call
4456 * mbedtls_ssl_get_version_number() to see what version was
4457 * negotiated.
4458 *
4459 * \note This function is deprecated and has been replaced by
4460 * \c mbedtls_ssl_conf_min_tls_version().
4461 *
4462 * \param conf SSL configuration
4463 * \param major Major version number (#MBEDTLS_SSL_MAJOR_VERSION_3)
4464 * \param minor Minor version number
4465 * (#MBEDTLS_SSL_MINOR_VERSION_3 for (D)TLS 1.2,
4466 * #MBEDTLS_SSL_MINOR_VERSION_4 for TLS 1.3)
4467 */
4468 void MBEDTLS_DEPRECATED mbedtls_ssl_conf_min_version(mbedtls_ssl_config *conf, int major,
4469 int minor);
4470 #endif /* MBEDTLS_DEPRECATED_REMOVED */
4471
4472 /**
4473 * \brief Set the minimum supported version sent from the client side
4474 * and/or accepted at the server side.
4475 *
4476 * \note After the handshake, you can call
4477 * mbedtls_ssl_get_version_number() to see what version was
4478 * negotiated.
4479 *
4480 * \param conf SSL configuration
4481 * \param tls_version TLS protocol version number (\c mbedtls_ssl_protocol_version)
4482 * (#MBEDTLS_SSL_VERSION_UNKNOWN is not valid)
4483 */
mbedtls_ssl_conf_min_tls_version(mbedtls_ssl_config * conf,mbedtls_ssl_protocol_version tls_version)4484 static inline void mbedtls_ssl_conf_min_tls_version(mbedtls_ssl_config *conf,
4485 mbedtls_ssl_protocol_version tls_version)
4486 {
4487 conf->MBEDTLS_PRIVATE(min_tls_version) = tls_version;
4488 }
4489
4490 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
4491 /**
4492 * \brief Enable or disable Encrypt-then-MAC
4493 * (Default: MBEDTLS_SSL_ETM_ENABLED)
4494 *
4495 * \note This should always be enabled, it is a security
4496 * improvement, and should not cause any interoperability
4497 * issue (used only if the peer supports it too).
4498 *
4499 * \param conf SSL configuration
4500 * \param etm MBEDTLS_SSL_ETM_ENABLED or MBEDTLS_SSL_ETM_DISABLED
4501 */
4502 void mbedtls_ssl_conf_encrypt_then_mac(mbedtls_ssl_config *conf, char etm);
4503 #endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
4504
4505 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
4506 /**
4507 * \brief Enable or disable Extended Master Secret negotiation.
4508 * (Default: MBEDTLS_SSL_EXTENDED_MS_ENABLED)
4509 *
4510 * \note This should always be enabled, it is a security fix to the
4511 * protocol, and should not cause any interoperability issue
4512 * (used only if the peer supports it too).
4513 *
4514 * \param conf SSL configuration
4515 * \param ems MBEDTLS_SSL_EXTENDED_MS_ENABLED or MBEDTLS_SSL_EXTENDED_MS_DISABLED
4516 */
4517 void mbedtls_ssl_conf_extended_master_secret(mbedtls_ssl_config *conf, char ems);
4518 #endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
4519
4520 #if defined(MBEDTLS_SSL_SRV_C)
4521 /**
4522 * \brief Whether to send a list of acceptable CAs in
4523 * CertificateRequest messages.
4524 * (Default: do send)
4525 *
4526 * \param conf SSL configuration
4527 * \param cert_req_ca_list MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or
4528 * MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED
4529 */
4530 void mbedtls_ssl_conf_cert_req_ca_list(mbedtls_ssl_config *conf,
4531 char cert_req_ca_list);
4532 #endif /* MBEDTLS_SSL_SRV_C */
4533
4534 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
4535 /**
4536 * \brief Set the maximum fragment length to emit and/or negotiate.
4537 * (Typical: the smaller of #MBEDTLS_SSL_IN_CONTENT_LEN and
4538 * #MBEDTLS_SSL_OUT_CONTENT_LEN, usually `2^14` bytes)
4539 * (Server: set maximum fragment length to emit,
4540 * usually negotiated by the client during handshake)
4541 * (Client: set maximum fragment length to emit *and*
4542 * negotiate with the server during handshake)
4543 * (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE)
4544 *
4545 * \note On the client side, the maximum fragment length extension
4546 * *will not* be used, unless the maximum fragment length has
4547 * been set via this function to a value different than
4548 * #MBEDTLS_SSL_MAX_FRAG_LEN_NONE.
4549 *
4550 * \note With TLS, this currently only affects ApplicationData (sent
4551 * with \c mbedtls_ssl_read()), not handshake messages.
4552 * With DTLS, this affects both ApplicationData and handshake.
4553 *
4554 * \note Defragmentation of TLS handshake messages is supported
4555 * with some limitations. See the documentation of
4556 * mbedtls_ssl_handshake() for details.
4557 *
4558 * \note This sets the maximum length for a record's payload,
4559 * excluding record overhead that will be added to it, see
4560 * \c mbedtls_ssl_get_record_expansion().
4561 *
4562 * \note For DTLS, it is also possible to set a limit for the total
4563 * size of datagrams passed to the transport layer, including
4564 * record overhead, see \c mbedtls_ssl_set_mtu().
4565 *
4566 * \param conf SSL configuration
4567 * \param mfl_code Code for maximum fragment length (allowed values:
4568 * MBEDTLS_SSL_MAX_FRAG_LEN_512, MBEDTLS_SSL_MAX_FRAG_LEN_1024,
4569 * MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096)
4570 *
4571 * \return 0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA
4572 */
4573 int mbedtls_ssl_conf_max_frag_len(mbedtls_ssl_config *conf, unsigned char mfl_code);
4574 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
4575
4576 #if defined(MBEDTLS_SSL_SRV_C)
4577 /**
4578 * \brief Pick the ciphersuites order according to the second parameter
4579 * in the SSL Server module (MBEDTLS_SSL_SRV_C).
4580 * (Default, if never called: MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER)
4581 *
4582 * \param conf SSL configuration
4583 * \param order Server or client (MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER
4584 * or MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_CLIENT)
4585 */
4586 void mbedtls_ssl_conf_preference_order(mbedtls_ssl_config *conf, int order);
4587 #endif /* MBEDTLS_SSL_SRV_C */
4588
4589 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
4590 /**
4591 * \brief Enable / Disable TLS 1.2 session tickets (client only,
4592 * TLS 1.2 only). Enabled by default.
4593 *
4594 * \note On server, use \c mbedtls_ssl_conf_session_tickets_cb().
4595 *
4596 * \param conf SSL configuration
4597 * \param use_tickets Enable or disable (#MBEDTLS_SSL_SESSION_TICKETS_ENABLED or
4598 * #MBEDTLS_SSL_SESSION_TICKETS_DISABLED)
4599 */
4600 void mbedtls_ssl_conf_session_tickets(mbedtls_ssl_config *conf, int use_tickets);
4601
4602 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
4603 /**
4604 * \brief Enable / Disable handling of TLS 1.3 NewSessionTicket messages
4605 * (client only, TLS 1.3 only).
4606 *
4607 * The handling of TLS 1.3 NewSessionTicket messages is disabled by
4608 * default.
4609 *
4610 * In TLS 1.3, servers may send a NewSessionTicket message at any time,
4611 * and may send multiple NewSessionTicket messages. By default, TLS 1.3
4612 * clients ignore NewSessionTicket messages.
4613 *
4614 * To support session tickets in TLS 1.3 clients, call this function
4615 * with #MBEDTLS_SSL_TLS1_3_SIGNAL_NEW_SESSION_TICKETS_ENABLED. When
4616 * this is enabled, when a client receives a NewSessionTicket message,
4617 * the next call to a message processing functions (notably
4618 * mbedtls_ssl_handshake() and mbedtls_ssl_read()) will return
4619 * #MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET. The client should then
4620 * call mbedtls_ssl_get_session() to retrieve the session ticket before
4621 * calling the same message processing function again.
4622 *
4623 * \param conf SSL configuration
4624 * \param signal_new_session_tickets Enable or disable
4625 * (#MBEDTLS_SSL_TLS1_3_SIGNAL_NEW_SESSION_TICKETS_ENABLED or
4626 * #MBEDTLS_SSL_TLS1_3_SIGNAL_NEW_SESSION_TICKETS_DISABLED)
4627 */
4628 void mbedtls_ssl_conf_tls13_enable_signal_new_session_tickets(
4629 mbedtls_ssl_config *conf, int signal_new_session_tickets);
4630
4631 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
4632 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
4633
4634 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && \
4635 defined(MBEDTLS_SSL_SRV_C) && \
4636 defined(MBEDTLS_SSL_PROTO_TLS1_3)
4637 /**
4638 * \brief Number of NewSessionTicket messages for the server to send
4639 * after handshake completion.
4640 *
4641 * \note The default value is
4642 * \c MBEDTLS_SSL_TLS1_3_DEFAULT_NEW_SESSION_TICKETS.
4643 *
4644 * \note In case of a session resumption, this setting only partially apply.
4645 * At most one ticket is sent in that case to just renew the pool of
4646 * tickets of the client. The rationale is to avoid the number of
4647 * tickets on the server to become rapidly out of control when the
4648 * server has the same configuration for all its connection instances.
4649 *
4650 * \param conf SSL configuration
4651 * \param num_tickets Number of NewSessionTicket.
4652 *
4653 */
4654 void mbedtls_ssl_conf_new_session_tickets(mbedtls_ssl_config *conf,
4655 uint16_t num_tickets);
4656 #endif /* MBEDTLS_SSL_SESSION_TICKETS &&
4657 MBEDTLS_SSL_SRV_C &&
4658 MBEDTLS_SSL_PROTO_TLS1_3*/
4659
4660 #if defined(MBEDTLS_SSL_RENEGOTIATION)
4661 /**
4662 * \brief Enable / Disable renegotiation support for connection when
4663 * initiated by peer
4664 * (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED)
4665 *
4666 * \warning It is recommended to always disable renegotiation unless you
4667 * know you need it and you know what you're doing. In the
4668 * past, there have been several issues associated with
4669 * renegotiation or a poor understanding of its properties.
4670 *
4671 * \note Server-side, enabling renegotiation also makes the server
4672 * susceptible to a resource DoS by a malicious client.
4673 *
4674 * \param conf SSL configuration
4675 * \param renegotiation Enable or disable (MBEDTLS_SSL_RENEGOTIATION_ENABLED or
4676 * MBEDTLS_SSL_RENEGOTIATION_DISABLED)
4677 */
4678 void mbedtls_ssl_conf_renegotiation(mbedtls_ssl_config *conf, int renegotiation);
4679 #endif /* MBEDTLS_SSL_RENEGOTIATION */
4680
4681 /**
4682 * \brief Prevent or allow legacy renegotiation.
4683 * (Default: MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION)
4684 *
4685 * MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION allows connections to
4686 * be established even if the peer does not support
4687 * secure renegotiation, but does not allow renegotiation
4688 * to take place if not secure.
4689 * (Interoperable and secure option)
4690 *
4691 * MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION allows renegotiations
4692 * with non-upgraded peers. Allowing legacy renegotiation
4693 * makes the connection vulnerable to specific man in the
4694 * middle attacks. (See RFC 5746)
4695 * (Most interoperable and least secure option)
4696 *
4697 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE breaks off connections
4698 * if peer does not support secure renegotiation. Results
4699 * in interoperability issues with non-upgraded peers
4700 * that do not support renegotiation altogether.
4701 * (Most secure option, interoperability issues)
4702 *
4703 * \param conf SSL configuration
4704 * \param allow_legacy Prevent or allow (SSL_NO_LEGACY_RENEGOTIATION,
4705 * SSL_ALLOW_LEGACY_RENEGOTIATION or
4706 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE)
4707 */
4708 void mbedtls_ssl_conf_legacy_renegotiation(mbedtls_ssl_config *conf, int allow_legacy);
4709
4710 #if defined(MBEDTLS_SSL_RENEGOTIATION)
4711 /**
4712 * \brief Enforce renegotiation requests.
4713 * (Default: enforced, max_records = 16)
4714 *
4715 * When we request a renegotiation, the peer can comply or
4716 * ignore the request. This function allows us to decide
4717 * whether to enforce our renegotiation requests by closing
4718 * the connection if the peer doesn't comply.
4719 *
4720 * However, records could already be in transit from the peer
4721 * when the request is emitted. In order to increase
4722 * reliability, we can accept a number of records before the
4723 * expected handshake records.
4724 *
4725 * The optimal value is highly dependent on the specific usage
4726 * scenario.
4727 *
4728 * \note With DTLS and server-initiated renegotiation, the
4729 * HelloRequest is retransmitted every time mbedtls_ssl_read() times
4730 * out or receives Application Data, until:
4731 * - max_records records have beens seen, if it is >= 0, or
4732 * - the number of retransmits that would happen during an
4733 * actual handshake has been reached.
4734 * Please remember the request might be lost a few times
4735 * if you consider setting max_records to a really low value.
4736 *
4737 * \warning On client, the grace period can only happen during
4738 * mbedtls_ssl_read(), as opposed to mbedtls_ssl_write() and mbedtls_ssl_renegotiate()
4739 * which always behave as if max_record was 0. The reason is,
4740 * if we receive application data from the server, we need a
4741 * place to write it, which only happens during mbedtls_ssl_read().
4742 *
4743 * \param conf SSL configuration
4744 * \param max_records Use MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to
4745 * enforce renegotiation, or a non-negative value to enforce
4746 * it but allow for a grace period of max_records records.
4747 */
4748 void mbedtls_ssl_conf_renegotiation_enforced(mbedtls_ssl_config *conf, int max_records);
4749
4750 /**
4751 * \brief Set record counter threshold for periodic renegotiation.
4752 * (Default: 2^48 - 1)
4753 *
4754 * Renegotiation is automatically triggered when a record
4755 * counter (outgoing or incoming) crosses the defined
4756 * threshold. The default value is meant to prevent the
4757 * connection from being closed when the counter is about to
4758 * reached its maximal value (it is not allowed to wrap).
4759 *
4760 * Lower values can be used to enforce policies such as "keys
4761 * must be refreshed every N packets with cipher X".
4762 *
4763 * The renegotiation period can be disabled by setting
4764 * conf->disable_renegotiation to
4765 * MBEDTLS_SSL_RENEGOTIATION_DISABLED.
4766 *
4767 * \note When the configured transport is
4768 * MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation
4769 * period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM,
4770 * the maximum renegotiation period is 2^64 - 1.
4771 *
4772 * \param conf SSL configuration
4773 * \param period The threshold value: a big-endian 64-bit number.
4774 */
4775 void mbedtls_ssl_conf_renegotiation_period(mbedtls_ssl_config *conf,
4776 const unsigned char period[8]);
4777 #endif /* MBEDTLS_SSL_RENEGOTIATION */
4778
4779 /**
4780 * \brief Check if there is data already read from the
4781 * underlying transport but not yet processed.
4782 *
4783 * \param ssl SSL context
4784 *
4785 * \return 0 if nothing's pending, 1 otherwise.
4786 *
4787 * \note This is different in purpose and behaviour from
4788 * \c mbedtls_ssl_get_bytes_avail in that it considers
4789 * any kind of unprocessed data, not only unread
4790 * application data. If \c mbedtls_ssl_get_bytes
4791 * returns a non-zero value, this function will
4792 * also signal pending data, but the converse does
4793 * not hold. For example, in DTLS there might be
4794 * further records waiting to be processed from
4795 * the current underlying transport's datagram.
4796 *
4797 * \note If this function returns 1 (data pending), this
4798 * does not imply that a subsequent call to
4799 * \c mbedtls_ssl_read will provide any data;
4800 * e.g., the unprocessed data might turn out
4801 * to be an alert or a handshake message.
4802 *
4803 * \note This function is useful in the following situation:
4804 * If the SSL/TLS module successfully returns from an
4805 * operation - e.g. a handshake or an application record
4806 * read - and you're awaiting incoming data next, you
4807 * must not immediately idle on the underlying transport
4808 * to have data ready, but you need to check the value
4809 * of this function first. The reason is that the desired
4810 * data might already be read but not yet processed.
4811 * If, in contrast, a previous call to the SSL/TLS module
4812 * returned MBEDTLS_ERR_SSL_WANT_READ, it is not necessary
4813 * to call this function, as the latter error code entails
4814 * that all internal data has been processed.
4815 *
4816 */
4817 int mbedtls_ssl_check_pending(const mbedtls_ssl_context *ssl);
4818
4819 /**
4820 * \brief Return the number of application data bytes
4821 * remaining to be read from the current record.
4822 *
4823 * \param ssl SSL context
4824 *
4825 * \return How many bytes are available in the application
4826 * data record read buffer.
4827 *
4828 * \note When working over a datagram transport, this is
4829 * useful to detect the current datagram's boundary
4830 * in case \c mbedtls_ssl_read has written the maximal
4831 * amount of data fitting into the input buffer.
4832 *
4833 */
4834 size_t mbedtls_ssl_get_bytes_avail(const mbedtls_ssl_context *ssl);
4835
4836 /**
4837 * \brief Return the result of the certificate verification
4838 *
4839 * \param ssl The SSL context to use.
4840 *
4841 * \return \c 0 if the certificate verification was successful.
4842 * \return \c -1u if the result is not available. This may happen
4843 * e.g. if the handshake aborts early, or a verification
4844 * callback returned a fatal error.
4845 * \return A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX
4846 * and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h.
4847 */
4848 uint32_t mbedtls_ssl_get_verify_result(const mbedtls_ssl_context *ssl);
4849
4850 /**
4851 * \brief Return the id of the current ciphersuite
4852 *
4853 * \param ssl SSL context
4854 *
4855 * \return a ciphersuite id
4856 */
4857 int mbedtls_ssl_get_ciphersuite_id_from_ssl(const mbedtls_ssl_context *ssl);
4858
4859 /**
4860 * \brief Return the name of the current ciphersuite
4861 *
4862 * \param ssl SSL context
4863 *
4864 * \return a string containing the ciphersuite name
4865 */
4866 const char *mbedtls_ssl_get_ciphersuite(const mbedtls_ssl_context *ssl);
4867
4868
4869 /**
4870 * \brief Return the (D)TLS protocol version negotiated in the
4871 * given connection.
4872 *
4873 * \note If you call this function too early during the initial
4874 * handshake, before the two sides have agreed on a version,
4875 * this function returns #MBEDTLS_SSL_VERSION_UNKNOWN.
4876 *
4877 * \param ssl The SSL context to query.
4878 * \return The negotiated protocol version.
4879 */
mbedtls_ssl_get_version_number(const mbedtls_ssl_context * ssl)4880 static inline mbedtls_ssl_protocol_version mbedtls_ssl_get_version_number(
4881 const mbedtls_ssl_context *ssl)
4882 {
4883 return ssl->MBEDTLS_PRIVATE(tls_version);
4884 }
4885
4886 /**
4887 * \brief Return the current TLS version
4888 *
4889 * \param ssl SSL context
4890 *
4891 * \return a string containing the TLS version
4892 */
4893 const char *mbedtls_ssl_get_version(const mbedtls_ssl_context *ssl);
4894
4895 /**
4896 * \brief Return the (maximum) number of bytes added by the record
4897 * layer: header + encryption/MAC overhead (inc. padding)
4898 *
4899 * \param ssl SSL context
4900 *
4901 * \return Current maximum record expansion in bytes
4902 */
4903 int mbedtls_ssl_get_record_expansion(const mbedtls_ssl_context *ssl);
4904
4905 /**
4906 * \brief Return the current maximum outgoing record payload in bytes.
4907 *
4908 * \note The logic to determine the maximum outgoing record payload is
4909 * version-specific. It takes into account various factors, such as
4910 * the mbedtls_config.h setting \c MBEDTLS_SSL_OUT_CONTENT_LEN, extensions
4911 * such as the max fragment length or record size limit extension if
4912 * used, and for DTLS the path MTU as configured and current
4913 * record expansion.
4914 *
4915 * \note With DTLS, \c mbedtls_ssl_write() will return an error if
4916 * called with a larger length value.
4917 * With TLS, \c mbedtls_ssl_write() will fragment the input if
4918 * necessary and return the number of bytes written; it is up
4919 * to the caller to call \c mbedtls_ssl_write() again in
4920 * order to send the remaining bytes if any.
4921 *
4922 * \sa mbedtls_ssl_get_max_out_record_payload()
4923 * \sa mbedtls_ssl_get_record_expansion()
4924 *
4925 * \param ssl SSL context
4926 *
4927 * \return Current maximum payload for an outgoing record,
4928 * or a negative error code.
4929 */
4930 int mbedtls_ssl_get_max_out_record_payload(const mbedtls_ssl_context *ssl);
4931
4932 /**
4933 * \brief Return the current maximum incoming record payload in bytes.
4934 *
4935 * \note The logic to determine the maximum incoming record payload is
4936 * version-specific. It takes into account various factors, such as
4937 * the mbedtls_config.h setting \c MBEDTLS_SSL_IN_CONTENT_LEN, extensions
4938 * such as the max fragment length extension or record size limit
4939 * extension if used, and the current record expansion.
4940 *
4941 * \sa mbedtls_ssl_set_mtu()
4942 * \sa mbedtls_ssl_get_max_in_record_payload()
4943 * \sa mbedtls_ssl_get_record_expansion()
4944 *
4945 * \param ssl SSL context
4946 *
4947 * \return Current maximum payload for an incoming record,
4948 * or a negative error code.
4949 */
4950 int mbedtls_ssl_get_max_in_record_payload(const mbedtls_ssl_context *ssl);
4951
4952 #if defined(MBEDTLS_X509_CRT_PARSE_C)
4953 /**
4954 * \brief Return the peer certificate from the current connection.
4955 *
4956 * \param ssl The SSL context to use. This must be initialized and setup.
4957 *
4958 * \return The current peer certificate, if available.
4959 * The returned certificate is owned by the SSL context and
4960 * is valid only until the next call to the SSL API.
4961 * \return \c NULL if no peer certificate is available. This might
4962 * be because the chosen ciphersuite doesn't use CRTs
4963 * (PSK-based ciphersuites, for example), or because
4964 * #MBEDTLS_SSL_KEEP_PEER_CERTIFICATE has been disabled,
4965 * allowing the stack to free the peer's CRT to save memory.
4966 *
4967 * \note For one-time inspection of the peer's certificate during
4968 * the handshake, consider registering an X.509 CRT verification
4969 * callback through mbedtls_ssl_conf_verify() instead of calling
4970 * this function. Using mbedtls_ssl_conf_verify() also comes at
4971 * the benefit of allowing you to influence the verification
4972 * process, for example by masking expected and tolerated
4973 * verification failures.
4974 *
4975 * \warning You must not use the pointer returned by this function
4976 * after any further call to the SSL API, including
4977 * mbedtls_ssl_read() and mbedtls_ssl_write(); this is
4978 * because the pointer might change during renegotiation,
4979 * which happens transparently to the user.
4980 * If you want to use the certificate across API calls,
4981 * you must make a copy.
4982 */
4983 const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert(const mbedtls_ssl_context *ssl);
4984 #endif /* MBEDTLS_X509_CRT_PARSE_C */
4985
4986 #if defined(MBEDTLS_SSL_CLI_C)
4987 /**
4988 * \brief Export a session in order to resume it later.
4989 *
4990 * \param ssl The SSL context representing the connection for which to
4991 * to export a session structure for later resumption.
4992 * \param session The target structure in which to store the exported session.
4993 * This must have been initialized with mbedtls_ssl_session_init()
4994 * but otherwise be unused.
4995 *
4996 * \note This function can handle a variety of mechanisms for session
4997 * resumption: For TLS 1.2, both session ID-based resumption and
4998 * ticket-based resumption will be considered. For TLS 1.3,
4999 * sessions equate to tickets, and if session tickets are
5000 * enabled (see #MBEDTLS_SSL_SESSION_TICKETS configuration
5001 * option), this function exports the last received ticket and
5002 * the exported session may be used to resume the TLS 1.3
5003 * session. If session tickets are disabled, exported sessions
5004 * cannot be used to resume a TLS 1.3 session.
5005 *
5006 * \return \c 0 if successful. In this case, \p session can be used for
5007 * session resumption by passing it to mbedtls_ssl_set_session(),
5008 * and serialized for storage via mbedtls_ssl_session_save().
5009 * \return Another negative error code on other kinds of failure.
5010 *
5011 * \sa mbedtls_ssl_set_session()
5012 * \sa mbedtls_ssl_session_save()
5013 */
5014 int mbedtls_ssl_get_session(const mbedtls_ssl_context *ssl,
5015 mbedtls_ssl_session *session);
5016 #endif /* MBEDTLS_SSL_CLI_C */
5017
5018 /**
5019 * \brief Perform the SSL handshake
5020 *
5021 * \param ssl SSL context
5022 *
5023 * \return \c 0 if successful.
5024 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
5025 * if the handshake is incomplete and waiting for data to
5026 * be available for reading from or writing to the underlying
5027 * transport - in this case you must call this function again
5028 * when the underlying transport is ready for the operation.
5029 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
5030 * operation is in progress (see
5031 * mbedtls_ssl_conf_async_private_cb()) - in this case you
5032 * must call this function again when the operation is ready.
5033 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
5034 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
5035 * in this case you must call this function again to complete
5036 * the handshake when you're done attending other tasks.
5037 * \return #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED if DTLS is in use
5038 * and the client did not demonstrate reachability yet - in
5039 * this case you must stop using the context (see below).
5040 * \return #MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET if a TLS 1.3
5041 * NewSessionTicket message has been received. See the
5042 * documentation of mbedtls_ssl_read() for more information
5043 * about this error code.
5044 * \return #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA if early data, as
5045 * defined in RFC 8446 (TLS 1.3 specification), has been
5046 * received as part of the handshake. This is server specific
5047 * and may occur only if the early data feature has been
5048 * enabled on server (see mbedtls_ssl_conf_early_data()
5049 * documentation). You must call mbedtls_ssl_read_early_data()
5050 * to read the early data before resuming the handshake.
5051 * \return Another SSL error code - in this case you must stop using
5052 * the context (see below).
5053 *
5054 * \warning If this function returns something other than
5055 * \c 0,
5056 * #MBEDTLS_ERR_SSL_WANT_READ,
5057 * #MBEDTLS_ERR_SSL_WANT_WRITE,
5058 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
5059 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
5060 * #MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET or
5061 * #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA,
5062 * you must stop using the SSL context for reading or writing,
5063 * and either free it or call \c mbedtls_ssl_session_reset()
5064 * on it before re-using it for a new connection; the current
5065 * connection must be closed.
5066 *
5067 * \note If DTLS is in use, then you may choose to handle
5068 * #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging
5069 * purposes, as it is an expected return value rather than an
5070 * actual error, but you still need to reset/free the context.
5071 *
5072 * \note Remarks regarding event-driven DTLS:
5073 * If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
5074 * from the underlying transport layer is currently being processed,
5075 * and it is safe to idle until the timer or the underlying transport
5076 * signal a new event. This is not true for a successful handshake,
5077 * in which case the datagram of the underlying transport that is
5078 * currently being processed might or might not contain further
5079 * DTLS records.
5080 *
5081 * \note If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto
5082 * subsystem must have been initialized by calling
5083 * psa_crypto_init() before calling this function.
5084 * Otherwise, the handshake may call psa_crypto_init()
5085 * if a negotiation involving TLS 1.3 takes place (this may
5086 * be the case even if TLS 1.3 is offered but eventually
5087 * not selected).
5088 *
5089 * \note In TLS, reception of fragmented handshake messages is
5090 * supported with some limitations (those limitations do
5091 * not apply to DTLS, where defragmentation is fully
5092 * supported):
5093 * - On an Mbed TLS server that only accepts TLS 1.2,
5094 * the initial ClientHello message must not be fragmented.
5095 * A TLS 1.2 ClientHello may be fragmented if the server
5096 * also accepts TLS 1.3 connections (meaning
5097 * that #MBEDTLS_SSL_PROTO_TLS1_3 enabled, and the
5098 * accepted versions have not been restricted with
5099 * mbedtls_ssl_conf_max_tls_version() or the like).
5100 * - The first fragment of a handshake message must be
5101 * at least 4 bytes long.
5102 * - Non-handshake records must not be interleaved between
5103 * the fragments of a handshake message. (This is permitted
5104 * in TLS 1.2 but not in TLS 1.3, but Mbed TLS rejects it
5105 * even in TLS 1.2.)
5106 */
5107 int mbedtls_ssl_handshake(mbedtls_ssl_context *ssl);
5108
5109 /**
5110 * \brief After calling mbedtls_ssl_handshake() to start the SSL
5111 * handshake you can call this function to check whether the
5112 * handshake is over for a given SSL context. This function
5113 * should be also used to determine when to stop calling
5114 * mbedtls_handshake_step() for that context.
5115 *
5116 * \param ssl SSL context
5117 *
5118 * \return \c 1 if handshake is over, \c 0 if it is still ongoing.
5119 */
mbedtls_ssl_is_handshake_over(mbedtls_ssl_context * ssl)5120 static inline int mbedtls_ssl_is_handshake_over(mbedtls_ssl_context *ssl)
5121 {
5122 return ssl->MBEDTLS_PRIVATE(state) >= MBEDTLS_SSL_HANDSHAKE_OVER;
5123 }
5124
5125 /**
5126 * \brief Perform a single step of the SSL handshake
5127 *
5128 * \note The state of the context (ssl->state) will be at
5129 * the next state after this function returns \c 0. Do not
5130 * call this function if mbedtls_ssl_is_handshake_over()
5131 * returns \c 1.
5132 *
5133 * \warning Whilst in the past you may have used direct access to the
5134 * context state (ssl->state) in order to ascertain when to
5135 * stop calling this function and although you can still do
5136 * so with something like ssl->MBEDTLS_PRIVATE(state) or by
5137 * defining MBEDTLS_ALLOW_PRIVATE_ACCESS, this is now
5138 * considered deprecated and could be broken in any future
5139 * release. If you still find you have good reason for such
5140 * direct access, then please do contact the team to explain
5141 * this (raise an issue or post to the mailing list), so that
5142 * we can add a solution to your problem that will be
5143 * guaranteed to work in the future.
5144 *
5145 * \param ssl SSL context
5146 *
5147 * \return See mbedtls_ssl_handshake().
5148 *
5149 * \warning If this function returns something other than \c 0,
5150 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
5151 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
5152 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
5153 * #MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET or
5154 * #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA, you must stop using
5155 * the SSL context for reading or writing, and either free it
5156 * or call \c mbedtls_ssl_session_reset() on it before
5157 * re-using it for a new connection; the current connection
5158 * must be closed.
5159 */
5160 int mbedtls_ssl_handshake_step(mbedtls_ssl_context *ssl);
5161
5162 #if defined(MBEDTLS_SSL_RENEGOTIATION)
5163 /**
5164 * \brief Initiate an SSL renegotiation on the running connection.
5165 * Client: perform the renegotiation right now.
5166 * Server: request renegotiation, which will be performed
5167 * during the next call to mbedtls_ssl_read() if honored by
5168 * client.
5169 *
5170 * \param ssl SSL context
5171 *
5172 * \return 0 if successful, or any mbedtls_ssl_handshake() return
5173 * value except #MBEDTLS_ERR_SSL_CLIENT_RECONNECT that can't
5174 * happen during a renegotiation.
5175 *
5176 * \warning If this function returns something other than \c 0,
5177 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
5178 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
5179 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
5180 * the SSL context for reading or writing, and either free it
5181 * or call \c mbedtls_ssl_session_reset() on it before
5182 * re-using it for a new connection; the current connection
5183 * must be closed.
5184 *
5185 */
5186 int mbedtls_ssl_renegotiate(mbedtls_ssl_context *ssl);
5187 #endif /* MBEDTLS_SSL_RENEGOTIATION */
5188
5189 /**
5190 * \brief Read at most 'len' application data bytes
5191 *
5192 * \param ssl SSL context
5193 * \param buf buffer that will hold the data
5194 * \param len maximum number of bytes to read
5195 *
5196 * \return The (positive) number of bytes read if successful.
5197 * \return \c 0 if the read end of the underlying transport was closed
5198 * without sending a CloseNotify beforehand, which might happen
5199 * because of various reasons (internal error of an underlying
5200 * stack, non-conformant peer not sending a CloseNotify and
5201 * such) - in this case you must stop using the context
5202 * (see below).
5203 * \return #MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY if the underlying
5204 * transport is still functional, but the peer has
5205 * acknowledged to not send anything anymore.
5206 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
5207 * if the handshake is incomplete and waiting for data to
5208 * be available for reading from or writing to the underlying
5209 * transport - in this case you must call this function again
5210 * when the underlying transport is ready for the operation.
5211 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
5212 * operation is in progress (see
5213 * mbedtls_ssl_conf_async_private_cb()) - in this case you
5214 * must call this function again when the operation is ready.
5215 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
5216 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
5217 * in this case you must call this function again to complete
5218 * the handshake when you're done attending other tasks.
5219 * \return #MBEDTLS_ERR_SSL_CLIENT_RECONNECT if we're at the server
5220 * side of a DTLS connection and the client is initiating a
5221 * new connection using the same source port. See below.
5222 * \return #MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET if a TLS 1.3
5223 * NewSessionTicket message has been received.
5224 * This error code is only returned on the client side. It is
5225 * only returned if handling of TLS 1.3 NewSessionTicket
5226 * messages has been enabled through
5227 * mbedtls_ssl_conf_tls13_enable_signal_new_session_tickets().
5228 * This error code indicates that a TLS 1.3 NewSessionTicket
5229 * message has been received and parsed successfully by the
5230 * client. The ticket data can be retrieved from the SSL
5231 * context by calling mbedtls_ssl_get_session(). It remains
5232 * available until the next call to mbedtls_ssl_read().
5233 * \return #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA if early data, as
5234 * defined in RFC 8446 (TLS 1.3 specification), has been
5235 * received as part of the handshake. This is server specific
5236 * and may occur only if the early data feature has been
5237 * enabled on server (see mbedtls_ssl_conf_early_data()
5238 * documentation). You must call mbedtls_ssl_read_early_data()
5239 * to read the early data before resuming the handshake.
5240 * \return Another SSL error code - in this case you must stop using
5241 * the context (see below).
5242 *
5243 * \warning If this function returns something other than
5244 * a positive value,
5245 * #MBEDTLS_ERR_SSL_WANT_READ,
5246 * #MBEDTLS_ERR_SSL_WANT_WRITE,
5247 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
5248 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
5249 * #MBEDTLS_ERR_SSL_CLIENT_RECONNECT or
5250 * #MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET or
5251 * #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA,
5252 * you must stop using the SSL context for reading or writing,
5253 * and either free it or call \c mbedtls_ssl_session_reset()
5254 * on it before re-using it for a new connection; the current
5255 * connection must be closed.
5256 *
5257 * \note When this function returns #MBEDTLS_ERR_SSL_CLIENT_RECONNECT
5258 * (which can only happen server-side), it means that a client
5259 * is initiating a new connection using the same source port.
5260 * You can either treat that as a connection close and wait
5261 * for the client to resend a ClientHello, or directly
5262 * continue with \c mbedtls_ssl_handshake() with the same
5263 * context (as it has been reset internally). Either way, you
5264 * must make sure this is seen by the application as a new
5265 * connection: application state, if any, should be reset, and
5266 * most importantly the identity of the client must be checked
5267 * again. WARNING: not validating the identity of the client
5268 * again, or not transmitting the new identity to the
5269 * application layer, would allow authentication bypass!
5270 *
5271 * \note Remarks regarding event-driven DTLS:
5272 * - If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
5273 * from the underlying transport layer is currently being processed,
5274 * and it is safe to idle until the timer or the underlying transport
5275 * signal a new event.
5276 * - This function may return MBEDTLS_ERR_SSL_WANT_READ even if data was
5277 * initially available on the underlying transport, as this data may have
5278 * been only e.g. duplicated messages or a renegotiation request.
5279 * Therefore, you must be prepared to receive MBEDTLS_ERR_SSL_WANT_READ even
5280 * when reacting to an incoming-data event from the underlying transport.
5281 * - On success, the datagram of the underlying transport that is currently
5282 * being processed may contain further DTLS records. You should call
5283 * \c mbedtls_ssl_check_pending to check for remaining records.
5284 *
5285 */
5286 int mbedtls_ssl_read(mbedtls_ssl_context *ssl, unsigned char *buf, size_t len);
5287
5288 /**
5289 * \brief Try to write exactly 'len' application data bytes
5290 *
5291 * \warning This function will do partial writes in some cases. If the
5292 * return value is non-negative but less than length, the
5293 * function must be called again with updated arguments:
5294 * buf + ret, len - ret (if ret is the return value) until
5295 * it returns a value equal to the last 'len' argument.
5296 *
5297 * \param ssl SSL context
5298 * \param buf buffer holding the data
5299 * \param len how many bytes must be written
5300 *
5301 * \return The (non-negative) number of bytes actually written if
5302 * successful (may be less than \p len).
5303 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
5304 * if the handshake is incomplete and waiting for data to
5305 * be available for reading from or writing to the underlying
5306 * transport - in this case you must call this function again
5307 * when the underlying transport is ready for the operation.
5308 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
5309 * operation is in progress (see
5310 * mbedtls_ssl_conf_async_private_cb()) - in this case you
5311 * must call this function again when the operation is ready.
5312 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
5313 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
5314 * in this case you must call this function again to complete
5315 * the handshake when you're done attending other tasks.
5316 * \return #MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET if a TLS 1.3
5317 * NewSessionTicket message has been received. See the
5318 * documentation of mbedtls_ssl_read() for more information
5319 * about this error code.
5320 * \return #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA if early data, as
5321 * defined in RFC 8446 (TLS 1.3 specification), has been
5322 * received as part of the handshake. This is server specific
5323 * and may occur only if the early data feature has been
5324 * enabled on server (see mbedtls_ssl_conf_early_data()
5325 * documentation). You must call mbedtls_ssl_read_early_data()
5326 * to read the early data before resuming the handshake.
5327 * \return Another SSL error code - in this case you must stop using
5328 * the context (see below).
5329 *
5330 * \warning If this function returns something other than
5331 * a non-negative value,
5332 * #MBEDTLS_ERR_SSL_WANT_READ,
5333 * #MBEDTLS_ERR_SSL_WANT_WRITE,
5334 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
5335 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
5336 * #MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET or
5337 * #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA,
5338 * you must stop using the SSL context for reading or writing,
5339 * and either free it or call \c mbedtls_ssl_session_reset()
5340 * on it before re-using it for a new connection; the current
5341 * connection must be closed.
5342 *
5343 * \note When this function returns #MBEDTLS_ERR_SSL_WANT_WRITE/READ,
5344 * it must be called later with the *same* arguments,
5345 * until it returns a value greater than or equal to 0. When
5346 * the function returns #MBEDTLS_ERR_SSL_WANT_WRITE there may be
5347 * some partial data in the output buffer, however this is not
5348 * yet sent.
5349 *
5350 * \note If the requested length is greater than the maximum
5351 * fragment length (either the built-in limit or the one set
5352 * or negotiated with the peer), then:
5353 * - with TLS, less bytes than requested are written.
5354 * - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned.
5355 * \c mbedtls_ssl_get_max_out_record_payload() may be used to
5356 * query the active maximum fragment length.
5357 *
5358 * \note Attempting to write 0 bytes will result in an empty TLS
5359 * application record being sent.
5360 */
5361 int mbedtls_ssl_write(mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len);
5362
5363 /**
5364 * \brief Send an alert message
5365 *
5366 * \param ssl SSL context
5367 * \param level The alert level of the message
5368 * (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL)
5369 * \param message The alert message (SSL_ALERT_MSG_*)
5370 *
5371 * \return 0 if successful, or a specific SSL error code.
5372 *
5373 * \note If this function returns something other than 0 or
5374 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
5375 * the SSL context for reading or writing, and either free it or
5376 * call \c mbedtls_ssl_session_reset() on it before re-using it
5377 * for a new connection; the current connection must be closed.
5378 */
5379 int mbedtls_ssl_send_alert_message(mbedtls_ssl_context *ssl,
5380 unsigned char level,
5381 unsigned char message);
5382 /**
5383 * \brief Notify the peer that the connection is being closed
5384 *
5385 * \param ssl SSL context
5386 *
5387 * \return 0 if successful, or a specific SSL error code.
5388 *
5389 * \note If this function returns something other than 0 or
5390 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
5391 * the SSL context for reading or writing, and either free it or
5392 * call \c mbedtls_ssl_session_reset() on it before re-using it
5393 * for a new connection; the current connection must be closed.
5394 */
5395 int mbedtls_ssl_close_notify(mbedtls_ssl_context *ssl);
5396
5397 #if defined(MBEDTLS_SSL_EARLY_DATA)
5398
5399 #if defined(MBEDTLS_SSL_SRV_C)
5400 /**
5401 * \brief Read at most 'len' bytes of early data
5402 *
5403 * \note This API is server specific.
5404 *
5405 * \warning Early data is defined in the TLS 1.3 specification, RFC 8446.
5406 * IMPORTANT NOTE from section 2.3 of the specification:
5407 *
5408 * The security properties for 0-RTT data are weaker than
5409 * those for other kinds of TLS data. Specifically:
5410 * - This data is not forward secret, as it is encrypted
5411 * solely under keys derived using the offered PSK.
5412 * - There are no guarantees of non-replay between connections.
5413 * Protection against replay for ordinary TLS 1.3 1-RTT data
5414 * is provided via the server's Random value, but 0-RTT data
5415 * does not depend on the ServerHello and therefore has
5416 * weaker guarantees. This is especially relevant if the
5417 * data is authenticated either with TLS client
5418 * authentication or inside the application protocol. The
5419 * same warnings apply to any use of the
5420 * early_exporter_master_secret.
5421 *
5422 * \warning Mbed TLS does not implement any of the anti-replay defenses
5423 * defined in section 8 of the TLS 1.3 specification:
5424 * single-use of tickets or ClientHello recording within a
5425 * given time window.
5426 *
5427 * \note This function is used in conjunction with
5428 * mbedtls_ssl_handshake(), mbedtls_ssl_handshake_step(),
5429 * mbedtls_ssl_read() and mbedtls_ssl_write() to read early
5430 * data when these functions return
5431 * #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA.
5432 *
5433 * \param ssl SSL context, it must have been initialized and set up.
5434 * \param buf buffer that will hold the data
5435 * \param len maximum number of bytes to read
5436 *
5437 * \return The (positive) number of bytes read if successful.
5438 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
5439 * \return #MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA if it is not
5440 * possible to read early data for the SSL context \p ssl. Note
5441 * that this function is intended to be called for an SSL
5442 * context \p ssl only after a call to mbedtls_ssl_handshake(),
5443 * mbedtls_ssl_handshake_step(), mbedtls_ssl_read() or
5444 * mbedtls_ssl_write() for \p ssl that has returned
5445 * #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA.
5446 */
5447 int mbedtls_ssl_read_early_data(mbedtls_ssl_context *ssl,
5448 unsigned char *buf, size_t len);
5449 #endif /* MBEDTLS_SSL_SRV_C */
5450
5451 #if defined(MBEDTLS_SSL_CLI_C)
5452 /**
5453 * \brief Try to write exactly 'len' application data bytes while
5454 * performing the handshake (early data).
5455 *
5456 * \warning Early data is defined in the TLS 1.3 specification, RFC 8446.
5457 * IMPORTANT NOTE from section 2.3 of the specification:
5458 *
5459 * The security properties for 0-RTT data are weaker than
5460 * those for other kinds of TLS data. Specifically:
5461 * - This data is not forward secret, as it is encrypted
5462 * solely under keys derived using the offered PSK.
5463 * - There are no guarantees of non-replay between connections.
5464 * Protection against replay for ordinary TLS 1.3 1-RTT data
5465 * is provided via the server's Random value, but 0-RTT data
5466 * does not depend on the ServerHello and therefore has
5467 * weaker guarantees. This is especially relevant if the
5468 * data is authenticated either with TLS client
5469 * authentication or inside the application protocol. The
5470 * same warnings apply to any use of the
5471 * early_exporter_master_secret.
5472 *
5473 * \note This function behaves mainly as mbedtls_ssl_write(). The
5474 * specification of mbedtls_ssl_write() relevant to TLS 1.3
5475 * (thus not the parts specific to (D)TLS1.2) applies to this
5476 * function and the present documentation is mainly restricted
5477 * to the differences with mbedtls_ssl_write(). One noticeable
5478 * difference though is that mbedtls_ssl_write() aims to
5479 * complete the handshake before to write application data
5480 * while mbedtls_ssl_write_early() aims to drive the handshake
5481 * just past the point where it is not possible to send early
5482 * data anymore.
5483 *
5484 * \param ssl SSL context
5485 * \param buf buffer holding the data
5486 * \param len how many bytes must be written
5487 *
5488 * \return The (non-negative) number of bytes actually written if
5489 * successful (may be less than \p len).
5490 *
5491 * \return One additional specific error code compared to
5492 * mbedtls_ssl_write():
5493 * #MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA.
5494 *
5495 * #MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA is returned when it
5496 * is not possible to write early data for the SSL context
5497 * \p ssl.
5498 *
5499 * It may have been possible and it is not possible
5500 * anymore because the client received the server Finished
5501 * message, the server rejected early data or the maximum
5502 * number of allowed early data for the PSK in use has been
5503 * reached.
5504 *
5505 * It may never have been possible and will never be possible
5506 * for the SSL context \p ssl because the use of early data
5507 * is disabled for that context or more generally the context
5508 * is not suitably configured to enable early data or the first
5509 * call to the function was done while the handshake was
5510 * already completed.
5511 *
5512 * It is not possible to write early data for the SSL context
5513 * \p ssl and any subsequent call to this API will return this
5514 * error code. But this does not preclude for using it with
5515 * mbedtls_ssl_write(), mbedtls_ssl_read() or
5516 * mbedtls_ssl_handshake() and the handshake can be
5517 * completed by calling one of these APIs.
5518 *
5519 * \note This function may write early data only if the SSL context
5520 * has been configured for the handshake with a PSK for which
5521 * early data is allowed.
5522 *
5523 * \note To maximize the number of early data that can be written in
5524 * the course of the handshake, it is expected that this
5525 * function starts the handshake for the SSL context \p ssl.
5526 * But this is not mandatory.
5527 *
5528 * \note This function does not provide any information on whether
5529 * the server has accepted or will accept early data or not.
5530 * When it returns a positive value, it just means that it
5531 * has written early data to the server. To know whether the
5532 * server has accepted early data or not, you should call
5533 * mbedtls_ssl_get_early_data_status() with the handshake
5534 * completed.
5535 */
5536 int mbedtls_ssl_write_early_data(mbedtls_ssl_context *ssl,
5537 const unsigned char *buf, size_t len);
5538
5539 /**
5540 * \brief Get the status of the negotiation of the use of early data.
5541 *
5542 * \param ssl The SSL context to query
5543 *
5544 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if this function is called
5545 * from the server-side.
5546 *
5547 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if this function is called
5548 * prior to completion of the handshake.
5549 *
5550 * \return #MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_INDICATED if the client
5551 * has not indicated the use of early data to the server.
5552 *
5553 * \return #MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED if the client has
5554 * indicated the use of early data and the server has accepted
5555 * it.
5556 *
5557 * \return #MBEDTLS_SSL_EARLY_DATA_STATUS_REJECTED if the client has
5558 * indicated the use of early data but the server has rejected
5559 * it. In this situation, the client may want to re-send the
5560 * early data it may have tried to send by calling
5561 * mbedtls_ssl_write_early_data() as ordinary post-handshake
5562 * application data by calling mbedtls_ssl_write().
5563 *
5564 */
5565 int mbedtls_ssl_get_early_data_status(mbedtls_ssl_context *ssl);
5566 #endif /* MBEDTLS_SSL_CLI_C */
5567
5568 #endif /* MBEDTLS_SSL_EARLY_DATA */
5569
5570 /**
5571 * \brief Free referenced items in an SSL context and clear memory
5572 *
5573 * \param ssl SSL context
5574 */
5575 void mbedtls_ssl_free(mbedtls_ssl_context *ssl);
5576
5577 #if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION)
5578 /**
5579 * \brief Save an active connection as serialized data in a buffer.
5580 * This allows the freeing or re-using of the SSL context
5581 * while still picking up the connection later in a way that
5582 * it entirely transparent to the peer.
5583 *
5584 * \see mbedtls_ssl_context_load()
5585 *
5586 * \note The serialized data only contains the data that is
5587 * necessary to resume the connection: negotiated protocol
5588 * options, session identifier, keys, etc.
5589 * Loading a saved SSL context does not restore settings and
5590 * state related to how the application accesses the context,
5591 * such as configured callback functions, user data, pending
5592 * incoming or outgoing data, etc.
5593 *
5594 * \note This feature is currently only available under certain
5595 * conditions, see the documentation of the return value
5596 * #MBEDTLS_ERR_SSL_BAD_INPUT_DATA for details.
5597 *
5598 * \note When this function succeeds, it calls
5599 * mbedtls_ssl_session_reset() on \p ssl which as a result is
5600 * no longer associated with the connection that has been
5601 * serialized. This avoids creating copies of the connection
5602 * state. You're then free to either re-use the context
5603 * structure for a different connection, or call
5604 * mbedtls_ssl_free() on it. See the documentation of
5605 * mbedtls_ssl_session_reset() for more details.
5606 *
5607 * \param ssl The SSL context to save. On success, it is no longer
5608 * associated with the connection that has been serialized.
5609 * \param buf The buffer to write the serialized data to. It must be a
5610 * writeable buffer of at least \p buf_len bytes, or may be \c
5611 * NULL if \p buf_len is \c 0.
5612 * \param buf_len The number of bytes available for writing in \p buf.
5613 * \param olen The size in bytes of the data that has been or would have
5614 * been written. It must point to a valid \c size_t.
5615 *
5616 * \note \p olen is updated to the correct value regardless of
5617 * whether \p buf_len was large enough. This makes it possible
5618 * to determine the necessary size by calling this function
5619 * with \p buf set to \c NULL and \p buf_len to \c 0. However,
5620 * the value of \p olen is only guaranteed to be correct when
5621 * the function returns #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL or
5622 * \c 0. If the return value is different, then the value of
5623 * \p olen is undefined.
5624 *
5625 * \return \c 0 if successful.
5626 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
5627 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed
5628 * while resetting the context.
5629 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if a handshake is in
5630 * progress, or there is pending data for reading or sending,
5631 * or the connection does not use DTLS 1.2 with an AEAD
5632 * ciphersuite, or renegotiation is enabled.
5633 */
5634 int mbedtls_ssl_context_save(mbedtls_ssl_context *ssl,
5635 unsigned char *buf,
5636 size_t buf_len,
5637 size_t *olen);
5638
5639 /**
5640 * \brief Load serialized connection data to an SSL context.
5641 *
5642 * \see mbedtls_ssl_context_save()
5643 *
5644 * \warning The same serialized data must never be loaded into more
5645 * that one context. In order to ensure that, after
5646 * successfully loading serialized data to an SSL context, you
5647 * should immediately destroy or invalidate all copies of the
5648 * serialized data that was loaded. Loading the same data in
5649 * more than one context would cause severe security failures
5650 * including but not limited to loss of confidentiality.
5651 *
5652 * \note Before calling this function, the SSL context must be
5653 * prepared in one of the two following ways. The first way is
5654 * to take a context freshly initialised with
5655 * mbedtls_ssl_init() and call mbedtls_ssl_setup() on it with
5656 * the same ::mbedtls_ssl_config structure that was used in
5657 * the original connection. The second way is to
5658 * call mbedtls_ssl_session_reset() on a context that was
5659 * previously prepared as above but used in the meantime.
5660 * Either way, you must not use the context to perform a
5661 * handshake between calling mbedtls_ssl_setup() or
5662 * mbedtls_ssl_session_reset() and calling this function. You
5663 * may however call other setter functions in that time frame
5664 * as indicated in the note below.
5665 *
5666 * \note Before or after calling this function successfully, you
5667 * also need to configure some connection-specific callbacks
5668 * and settings before you can use the connection again
5669 * (unless they were already set before calling
5670 * mbedtls_ssl_session_reset() and the values are suitable for
5671 * the present connection). Specifically, you want to call
5672 * at least mbedtls_ssl_set_bio(),
5673 * mbedtls_ssl_set_timer_cb(), and
5674 * mbedtls_ssl_set_user_data_n() or
5675 * mbedtls_ssl_set_user_data_p() if they were set originally.
5676 * All other SSL setter functions
5677 * are not necessary to call, either because they're only used
5678 * in handshakes, or because the setting is already saved. You
5679 * might choose to call them anyway, for example in order to
5680 * share code between the cases of establishing a new
5681 * connection and the case of loading an already-established
5682 * connection.
5683 *
5684 * \note If you have new information about the path MTU, you want to
5685 * call mbedtls_ssl_set_mtu() after calling this function, as
5686 * otherwise this function would overwrite your
5687 * newly-configured value with the value that was active when
5688 * the context was saved.
5689 *
5690 * \note When this function returns an error code, it calls
5691 * mbedtls_ssl_free() on \p ssl. In this case, you need to
5692 * prepare the context with the usual sequence starting with a
5693 * call to mbedtls_ssl_init() if you want to use it again.
5694 *
5695 * \param ssl The SSL context structure to be populated. It must have
5696 * been prepared as described in the note above.
5697 * \param buf The buffer holding the serialized connection data. It must
5698 * be a readable buffer of at least \p len bytes.
5699 * \param len The size of the serialized data in bytes.
5700 *
5701 * \return \c 0 if successful.
5702 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
5703 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
5704 * comes from a different Mbed TLS version or build.
5705 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
5706 */
5707 int mbedtls_ssl_context_load(mbedtls_ssl_context *ssl,
5708 const unsigned char *buf,
5709 size_t len);
5710 #endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */
5711
5712 /**
5713 * \brief Initialize an SSL configuration context
5714 * Just makes the context ready for
5715 * mbedtls_ssl_config_defaults() or mbedtls_ssl_config_free().
5716 *
5717 * \note You need to call mbedtls_ssl_config_defaults() unless you
5718 * manually set all of the relevant fields yourself.
5719 *
5720 * \param conf SSL configuration context
5721 */
5722 void mbedtls_ssl_config_init(mbedtls_ssl_config *conf);
5723
5724 /**
5725 * \brief Load reasonable default SSL configuration values.
5726 * (You need to call mbedtls_ssl_config_init() first.)
5727 *
5728 * \param conf SSL configuration context
5729 * \param endpoint MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
5730 * \param transport MBEDTLS_SSL_TRANSPORT_STREAM for TLS, or
5731 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS
5732 * \param preset a MBEDTLS_SSL_PRESET_XXX value
5733 *
5734 * \note See \c mbedtls_ssl_conf_transport() for notes on DTLS.
5735 *
5736 * \return 0 if successful, or
5737 * MBEDTLS_ERR_XXX_ALLOC_FAILED on memory allocation error.
5738 */
5739 int mbedtls_ssl_config_defaults(mbedtls_ssl_config *conf,
5740 int endpoint, int transport, int preset);
5741
5742 /**
5743 * \brief Free an SSL configuration context
5744 *
5745 * \param conf SSL configuration context
5746 */
5747 void mbedtls_ssl_config_free(mbedtls_ssl_config *conf);
5748
5749 /**
5750 * \brief Initialize SSL session structure
5751 *
5752 * \param session SSL session
5753 */
5754 void mbedtls_ssl_session_init(mbedtls_ssl_session *session);
5755
5756 /**
5757 * \brief Free referenced items in an SSL session including the
5758 * peer certificate and clear memory
5759 *
5760 * \note A session object can be freed even if the SSL context
5761 * that was used to retrieve the session is still in use.
5762 *
5763 * \param session SSL session
5764 */
5765 void mbedtls_ssl_session_free(mbedtls_ssl_session *session);
5766
5767 /**
5768 * \brief TLS-PRF function for key derivation.
5769 *
5770 * \param prf The tls_prf type function type to be used.
5771 * \param secret Secret for the key derivation function.
5772 * \param slen Length of the secret.
5773 * \param label String label for the key derivation function,
5774 * terminated with null character.
5775 * \param random Random bytes.
5776 * \param rlen Length of the random bytes buffer.
5777 * \param dstbuf The buffer holding the derived key.
5778 * \param dlen Length of the output buffer.
5779 *
5780 * \return 0 on success. An SSL specific error on failure.
5781 */
5782 int mbedtls_ssl_tls_prf(const mbedtls_tls_prf_types prf,
5783 const unsigned char *secret, size_t slen,
5784 const char *label,
5785 const unsigned char *random, size_t rlen,
5786 unsigned char *dstbuf, size_t dlen);
5787
5788 #if defined(MBEDTLS_SSL_KEYING_MATERIAL_EXPORT)
5789 /* Maximum value for key_len in mbedtls_ssl_export_keying material. Depending on the TLS
5790 * version and the negotiated ciphersuite, larger keys could in principle be exported,
5791 * but for simplicity, we define one limit that works in all cases. TLS 1.3 with SHA256
5792 * has the strictest limit: 255 blocks of SHA256 output, or 8160 bytes. */
5793 #define MBEDTLS_SSL_EXPORT_MAX_KEY_LEN 8160
5794
5795 /**
5796 * \brief TLS-Exporter to derive shared symmetric keys between server and client.
5797 *
5798 * \param ssl SSL context from which to export keys. Must have finished the handshake.
5799 * \param out Output buffer of length at least key_len bytes.
5800 * \param key_len Length of the key to generate in bytes, must be at most
5801 * MBEDTLS_SSL_EXPORT_MAX_KEY_LEN (8160).
5802 * \param label Label for which to generate the key of length label_len.
5803 * \param label_len Length of label in bytes. Must be at most 249 in TLS 1.3.
5804 * \param context Context of the key. Can be NULL if context_len or use_context is 0.
5805 * \param context_len Length of context. Must be < 2^16 in TLS 1.2.
5806 * \param use_context Indicates if a context should be used in deriving the key.
5807 *
5808 * \note TLS 1.2 makes a distinction between a 0-length context and no context.
5809 * This is why the use_context argument exists. TLS 1.3 does not make
5810 * this distinction. If use_context is 0 and TLS 1.3 is used, context and
5811 * context_len are ignored and a 0-length context is used.
5812 *
5813 * \return 0 on success.
5814 * \return MBEDTLS_ERR_SSL_BAD_INPUT_DATA if the handshake is not yet completed.
5815 * \return An SSL-specific error on failure.
5816 */
5817 int mbedtls_ssl_export_keying_material(mbedtls_ssl_context *ssl,
5818 uint8_t *out, const size_t key_len,
5819 const char *label, const size_t label_len,
5820 const unsigned char *context, const size_t context_len,
5821 const int use_context);
5822 #endif
5823 #ifdef __cplusplus
5824 }
5825 #endif
5826
5827 #endif /* ssl.h */
5828