1 /**
2 * \file ssl.h
3 *
4 * \brief SSL/TLS functions.
5 */
6 /*
7 * Copyright The Mbed TLS Contributors
8 * SPDX-License-Identifier: Apache-2.0
9 *
10 * Licensed under the Apache License, Version 2.0 (the "License"); you may
11 * not use this file except in compliance with the License.
12 * You may obtain a copy of the License at
13 *
14 * http://www.apache.org/licenses/LICENSE-2.0
15 *
16 * Unless required by applicable law or agreed to in writing, software
17 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
18 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
19 * See the License for the specific language governing permissions and
20 * limitations under the License.
21 */
22 #ifndef MBEDTLS_SSL_H
23 #define MBEDTLS_SSL_H
24
25 #if !defined(MBEDTLS_CONFIG_FILE)
26 #include "mbedtls/config.h"
27 #else
28 #include MBEDTLS_CONFIG_FILE
29 #endif
30
31 #include "mbedtls/bignum.h"
32 #include "mbedtls/ecp.h"
33
34 #include "mbedtls/ssl_ciphersuites.h"
35
36 #if defined(MBEDTLS_X509_CRT_PARSE_C)
37 #include "mbedtls/x509_crt.h"
38 #include "mbedtls/x509_crl.h"
39 #endif
40
41 #if defined(MBEDTLS_DHM_C)
42 #include "mbedtls/dhm.h"
43 #endif
44
45 /* Adding guard for MBEDTLS_ECDSA_C to ensure no compile errors due
46 * to guards also being in ssl_srv.c and ssl_cli.c. There is a gap
47 * in functionality that access to ecdh_ctx structure is needed for
48 * MBEDTLS_ECDSA_C which does not seem correct.
49 */
50 #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C)
51 #include "mbedtls/ecdh.h"
52 #endif
53
54 #if defined(MBEDTLS_ZLIB_SUPPORT)
55
56 #if defined(MBEDTLS_DEPRECATED_WARNING)
57 #warning "Record compression support via MBEDTLS_ZLIB_SUPPORT is deprecated and will be removed in the next major revision of the library"
58 #endif
59
60 #if defined(MBEDTLS_DEPRECATED_REMOVED)
61 #error "Record compression support via MBEDTLS_ZLIB_SUPPORT is deprecated and cannot be used if MBEDTLS_DEPRECATED_REMOVED is set"
62 #endif
63
64 #include "zlib.h"
65 #endif
66
67 #if defined(MBEDTLS_HAVE_TIME)
68 #include "mbedtls/platform_time.h"
69 #endif
70
71 #if defined(MBEDTLS_USE_PSA_CRYPTO)
72 #include "psa/crypto.h"
73 #endif /* MBEDTLS_USE_PSA_CRYPTO */
74
75 /*
76 * SSL Error codes
77 */
78 #define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE -0x7080 /**< The requested feature is not available. */
79 #define MBEDTLS_ERR_SSL_BAD_INPUT_DATA -0x7100 /**< Bad input parameters to function. */
80 #define MBEDTLS_ERR_SSL_INVALID_MAC -0x7180 /**< Verification of the message MAC failed. */
81 #define MBEDTLS_ERR_SSL_INVALID_RECORD -0x7200 /**< An invalid SSL record was received. */
82 #define MBEDTLS_ERR_SSL_CONN_EOF -0x7280 /**< The connection indicated an EOF. */
83 #define MBEDTLS_ERR_SSL_UNKNOWN_CIPHER -0x7300 /**< An unknown cipher was received. */
84 #define MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN -0x7380 /**< The server has no ciphersuites in common with the client. */
85 #define MBEDTLS_ERR_SSL_NO_RNG -0x7400 /**< No RNG was provided to the SSL module. */
86 #define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE -0x7480 /**< No client certification received from the client, but required by the authentication mode. */
87 #define MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE -0x7500 /**< Our own certificate(s) is/are too large to send in an SSL message. */
88 #define MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED -0x7580 /**< The own certificate is not set, but needed by the server. */
89 #define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED -0x7600 /**< The own private key or pre-shared key is not set, but needed. */
90 #define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED -0x7680 /**< No CA Chain is set, but required to operate. */
91 #define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE -0x7700 /**< An unexpected message was received from our peer. */
92 #define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE -0x7780 /**< A fatal alert message was received from our peer. */
93 #define MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED -0x7800 /**< Verification of our peer failed. */
94 #define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY -0x7880 /**< The peer notified us that the connection is going to be closed. */
95 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO -0x7900 /**< Processing of the ClientHello handshake message failed. */
96 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO -0x7980 /**< Processing of the ServerHello handshake message failed. */
97 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE -0x7A00 /**< Processing of the Certificate handshake message failed. */
98 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST -0x7A80 /**< Processing of the CertificateRequest handshake message failed. */
99 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE -0x7B00 /**< Processing of the ServerKeyExchange handshake message failed. */
100 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE -0x7B80 /**< Processing of the ServerHelloDone handshake message failed. */
101 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE -0x7C00 /**< Processing of the ClientKeyExchange handshake message failed. */
102 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP -0x7C80 /**< Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Read Public. */
103 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_CS -0x7D00 /**< Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Calculate Secret. */
104 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY -0x7D80 /**< Processing of the CertificateVerify handshake message failed. */
105 #define MBEDTLS_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC -0x7E00 /**< Processing of the ChangeCipherSpec handshake message failed. */
106 #define MBEDTLS_ERR_SSL_BAD_HS_FINISHED -0x7E80 /**< Processing of the Finished handshake message failed. */
107 #define MBEDTLS_ERR_SSL_ALLOC_FAILED -0x7F00 /**< Memory allocation failed */
108 #define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED -0x7F80 /**< Hardware acceleration function returned with error */
109 #define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH -0x6F80 /**< Hardware acceleration function skipped / left alone data */
110 #define MBEDTLS_ERR_SSL_COMPRESSION_FAILED -0x6F00 /**< Processing of the compression / decompression failed */
111 #define MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION -0x6E80 /**< Handshake protocol not within min/max boundaries */
112 #define MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET -0x6E00 /**< Processing of the NewSessionTicket handshake message failed. */
113 #define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED -0x6D80 /**< Session ticket has expired. */
114 #define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH -0x6D00 /**< Public key type mismatch (eg, asked for RSA key exchange and presented EC key) */
115 #define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY -0x6C80 /**< Unknown identity received (eg, PSK identity) */
116 #define MBEDTLS_ERR_SSL_INTERNAL_ERROR -0x6C00 /**< Internal error (eg, unexpected failure in lower-level module) */
117 #define MBEDTLS_ERR_SSL_COUNTER_WRAPPING -0x6B80 /**< A counter would wrap (eg, too many messages exchanged). */
118 #define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO -0x6B00 /**< Unexpected message at ServerHello in renegotiation. */
119 #define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED -0x6A80 /**< DTLS client must retry for hello verification */
120 #define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL -0x6A00 /**< A buffer is too small to receive or write a message */
121 #define MBEDTLS_ERR_SSL_NO_USABLE_CIPHERSUITE -0x6980 /**< None of the common ciphersuites is usable (eg, no suitable certificate, see debug messages). */
122 #define MBEDTLS_ERR_SSL_WANT_READ -0x6900 /**< No data of requested type currently available on underlying transport. */
123 #define MBEDTLS_ERR_SSL_WANT_WRITE -0x6880 /**< Connection requires a write call. */
124 #define MBEDTLS_ERR_SSL_TIMEOUT -0x6800 /**< The operation timed out. */
125 #define MBEDTLS_ERR_SSL_CLIENT_RECONNECT -0x6780 /**< The client initiated a reconnect from the same port. */
126 #define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD -0x6700 /**< Record header looks valid but is not expected. */
127 #define MBEDTLS_ERR_SSL_NON_FATAL -0x6680 /**< The alert message received indicates a non-fatal error. */
128 #define MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH -0x6600 /**< Couldn't set the hash for verifying CertificateVerify */
129 #define MBEDTLS_ERR_SSL_CONTINUE_PROCESSING -0x6580 /**< Internal-only message signaling that further message-processing should be done */
130 #define MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS -0x6500 /**< The asynchronous operation is not completed yet. */
131 #define MBEDTLS_ERR_SSL_EARLY_MESSAGE -0x6480 /**< Internal-only message signaling that a message arrived early. */
132 #define MBEDTLS_ERR_SSL_UNEXPECTED_CID -0x6000 /**< An encrypted DTLS-frame with an unexpected CID was received. */
133 #define MBEDTLS_ERR_SSL_VERSION_MISMATCH -0x5F00 /**< An operation failed due to an unexpected version or configuration. */
134 #define MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS -0x7000 /**< A cryptographic operation is in progress. Try again later. */
135 #define MBEDTLS_ERR_SSL_BAD_CONFIG -0x5E80 /**< Invalid value in SSL config */
136
137 /*
138 * Various constants
139 */
140 #define MBEDTLS_SSL_MAJOR_VERSION_3 3
141 #define MBEDTLS_SSL_MINOR_VERSION_0 0 /*!< SSL v3.0 */
142 #define MBEDTLS_SSL_MINOR_VERSION_1 1 /*!< TLS v1.0 */
143 #define MBEDTLS_SSL_MINOR_VERSION_2 2 /*!< TLS v1.1 */
144 #define MBEDTLS_SSL_MINOR_VERSION_3 3 /*!< TLS v1.2 */
145 #define MBEDTLS_SSL_MINOR_VERSION_4 4 /*!< TLS v1.3 (experimental) */
146
147 #define MBEDTLS_SSL_TRANSPORT_STREAM 0 /*!< TLS */
148 #define MBEDTLS_SSL_TRANSPORT_DATAGRAM 1 /*!< DTLS */
149
150 #define MBEDTLS_SSL_MAX_HOST_NAME_LEN 255 /*!< Maximum host name defined in RFC 1035 */
151 #define MBEDTLS_SSL_MAX_ALPN_NAME_LEN 255 /*!< Maximum size in bytes of a protocol name in alpn ext., RFC 7301 */
152
153 #define MBEDTLS_SSL_MAX_ALPN_LIST_LEN 65535 /*!< Maximum size in bytes of list in alpn ext., RFC 7301 */
154
155 /* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
156 * NONE must be zero so that memset()ing structure to zero works */
157 #define MBEDTLS_SSL_MAX_FRAG_LEN_NONE 0 /*!< don't use this extension */
158 #define MBEDTLS_SSL_MAX_FRAG_LEN_512 1 /*!< MaxFragmentLength 2^9 */
159 #define MBEDTLS_SSL_MAX_FRAG_LEN_1024 2 /*!< MaxFragmentLength 2^10 */
160 #define MBEDTLS_SSL_MAX_FRAG_LEN_2048 3 /*!< MaxFragmentLength 2^11 */
161 #define MBEDTLS_SSL_MAX_FRAG_LEN_4096 4 /*!< MaxFragmentLength 2^12 */
162 #define MBEDTLS_SSL_MAX_FRAG_LEN_INVALID 5 /*!< first invalid value */
163
164 #define MBEDTLS_SSL_IS_CLIENT 0
165 #define MBEDTLS_SSL_IS_SERVER 1
166
167 #define MBEDTLS_SSL_IS_NOT_FALLBACK 0
168 #define MBEDTLS_SSL_IS_FALLBACK 1
169
170 #define MBEDTLS_SSL_EXTENDED_MS_DISABLED 0
171 #define MBEDTLS_SSL_EXTENDED_MS_ENABLED 1
172
173 #define MBEDTLS_SSL_CID_DISABLED 0
174 #define MBEDTLS_SSL_CID_ENABLED 1
175
176 #define MBEDTLS_SSL_ETM_DISABLED 0
177 #define MBEDTLS_SSL_ETM_ENABLED 1
178
179 #define MBEDTLS_SSL_COMPRESS_NULL 0
180 #define MBEDTLS_SSL_COMPRESS_DEFLATE 1
181
182 #define MBEDTLS_SSL_VERIFY_NONE 0
183 #define MBEDTLS_SSL_VERIFY_OPTIONAL 1
184 #define MBEDTLS_SSL_VERIFY_REQUIRED 2
185 #define MBEDTLS_SSL_VERIFY_UNSET 3 /* Used only for sni_authmode */
186
187 #define MBEDTLS_SSL_LEGACY_RENEGOTIATION 0
188 #define MBEDTLS_SSL_SECURE_RENEGOTIATION 1
189
190 #define MBEDTLS_SSL_RENEGOTIATION_DISABLED 0
191 #define MBEDTLS_SSL_RENEGOTIATION_ENABLED 1
192
193 #define MBEDTLS_SSL_ANTI_REPLAY_DISABLED 0
194 #define MBEDTLS_SSL_ANTI_REPLAY_ENABLED 1
195
196 #define MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED -1
197 #define MBEDTLS_SSL_RENEGO_MAX_RECORDS_DEFAULT 16
198
199 #define MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION 0
200 #define MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION 1
201 #define MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE 2
202
203 #define MBEDTLS_SSL_TRUNC_HMAC_DISABLED 0
204 #define MBEDTLS_SSL_TRUNC_HMAC_ENABLED 1
205 #define MBEDTLS_SSL_TRUNCATED_HMAC_LEN 10 /* 80 bits, rfc 6066 section 7 */
206
207 #define MBEDTLS_SSL_SESSION_TICKETS_DISABLED 0
208 #define MBEDTLS_SSL_SESSION_TICKETS_ENABLED 1
209
210 #define MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED 0
211 #define MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED 1
212
213 #define MBEDTLS_SSL_ARC4_ENABLED 0
214 #define MBEDTLS_SSL_ARC4_DISABLED 1
215
216 #define MBEDTLS_SSL_PRESET_DEFAULT 0
217 #define MBEDTLS_SSL_PRESET_SUITEB 2
218
219 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED 1
220 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 0
221
222 #define MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED 0
223 #define MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED 1
224
225 /*
226 * Default range for DTLS retransmission timer value, in milliseconds.
227 * RFC 6347 4.2.4.1 says from 1 second to 60 seconds.
228 */
229 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN 1000
230 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX 60000
231
232 /**
233 * \name SECTION: Module settings
234 *
235 * The configuration options you can set for this module are in this section.
236 * Either change them in config.h or define them on the compiler command line.
237 * \{
238 */
239
240 #if !defined(MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME)
241 #define MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME 86400 /**< Lifetime of session tickets (if enabled) */
242 #endif
243
244 /*
245 * Maximum fragment length in bytes,
246 * determines the size of each of the two internal I/O buffers.
247 *
248 * Note: the RFC defines the default size of SSL / TLS messages. If you
249 * change the value here, other clients / servers may not be able to
250 * communicate with you anymore. Only change this value if you control
251 * both sides of the connection and have it reduced at both sides, or
252 * if you're using the Max Fragment Length extension and you know all your
253 * peers are using it too!
254 */
255 #if !defined(MBEDTLS_SSL_MAX_CONTENT_LEN)
256 #define MBEDTLS_SSL_MAX_CONTENT_LEN 16384 /**< Size of the input / output buffer */
257 #endif
258
259 #if !defined(MBEDTLS_SSL_IN_CONTENT_LEN)
260 #define MBEDTLS_SSL_IN_CONTENT_LEN MBEDTLS_SSL_MAX_CONTENT_LEN
261 #endif
262
263 #if !defined(MBEDTLS_SSL_OUT_CONTENT_LEN)
264 #define MBEDTLS_SSL_OUT_CONTENT_LEN MBEDTLS_SSL_MAX_CONTENT_LEN
265 #endif
266
267 /*
268 * Maximum number of heap-allocated bytes for the purpose of
269 * DTLS handshake message reassembly and future message buffering.
270 */
271 #if !defined(MBEDTLS_SSL_DTLS_MAX_BUFFERING)
272 #define MBEDTLS_SSL_DTLS_MAX_BUFFERING 32768
273 #endif
274
275 /*
276 * Maximum length of CIDs for incoming and outgoing messages.
277 */
278 #if !defined(MBEDTLS_SSL_CID_IN_LEN_MAX)
279 #define MBEDTLS_SSL_CID_IN_LEN_MAX 32
280 #endif
281
282 #if !defined(MBEDTLS_SSL_CID_OUT_LEN_MAX)
283 #define MBEDTLS_SSL_CID_OUT_LEN_MAX 32
284 #endif
285
286 #if !defined(MBEDTLS_SSL_CID_PADDING_GRANULARITY)
287 #define MBEDTLS_SSL_CID_PADDING_GRANULARITY 16
288 #endif
289
290 #if !defined(MBEDTLS_SSL_TLS1_3_PADDING_GRANULARITY)
291 #define MBEDTLS_SSL_TLS1_3_PADDING_GRANULARITY 1
292 #endif
293
294 /* \} name SECTION: Module settings */
295
296 /*
297 * Length of the verify data for secure renegotiation
298 */
299 #if defined(MBEDTLS_SSL_PROTO_SSL3)
300 #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 36
301 #else
302 #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 12
303 #endif
304
305 /*
306 * Signaling ciphersuite values (SCSV)
307 */
308 #define MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO 0xFF /**< renegotiation info ext */
309 #define MBEDTLS_SSL_FALLBACK_SCSV_VALUE 0x5600 /**< RFC 7507 section 2 */
310
311 /*
312 * Supported Signature and Hash algorithms (For TLS 1.2)
313 * RFC 5246 section 7.4.1.4.1
314 */
315 #define MBEDTLS_SSL_HASH_NONE 0
316 #define MBEDTLS_SSL_HASH_MD5 1
317 #define MBEDTLS_SSL_HASH_SHA1 2
318 #define MBEDTLS_SSL_HASH_SHA224 3
319 #define MBEDTLS_SSL_HASH_SHA256 4
320 #define MBEDTLS_SSL_HASH_SHA384 5
321 #define MBEDTLS_SSL_HASH_SHA512 6
322
323 #define MBEDTLS_SSL_SIG_ANON 0
324 #define MBEDTLS_SSL_SIG_RSA 1
325 #define MBEDTLS_SSL_SIG_ECDSA 3
326
327 /*
328 * Client Certificate Types
329 * RFC 5246 section 7.4.4 plus RFC 4492 section 5.5
330 */
331 #define MBEDTLS_SSL_CERT_TYPE_RSA_SIGN 1
332 #define MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN 64
333
334 /*
335 * Message, alert and handshake types
336 */
337 #define MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC 20
338 #define MBEDTLS_SSL_MSG_ALERT 21
339 #define MBEDTLS_SSL_MSG_HANDSHAKE 22
340 #define MBEDTLS_SSL_MSG_APPLICATION_DATA 23
341 #define MBEDTLS_SSL_MSG_CID 25
342
343 #define MBEDTLS_SSL_ALERT_LEVEL_WARNING 1
344 #define MBEDTLS_SSL_ALERT_LEVEL_FATAL 2
345
346 #define MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY 0 /* 0x00 */
347 #define MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE 10 /* 0x0A */
348 #define MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC 20 /* 0x14 */
349 #define MBEDTLS_SSL_ALERT_MSG_DECRYPTION_FAILED 21 /* 0x15 */
350 #define MBEDTLS_SSL_ALERT_MSG_RECORD_OVERFLOW 22 /* 0x16 */
351 #define MBEDTLS_SSL_ALERT_MSG_DECOMPRESSION_FAILURE 30 /* 0x1E */
352 #define MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE 40 /* 0x28 */
353 #define MBEDTLS_SSL_ALERT_MSG_NO_CERT 41 /* 0x29 */
354 #define MBEDTLS_SSL_ALERT_MSG_BAD_CERT 42 /* 0x2A */
355 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT 43 /* 0x2B */
356 #define MBEDTLS_SSL_ALERT_MSG_CERT_REVOKED 44 /* 0x2C */
357 #define MBEDTLS_SSL_ALERT_MSG_CERT_EXPIRED 45 /* 0x2D */
358 #define MBEDTLS_SSL_ALERT_MSG_CERT_UNKNOWN 46 /* 0x2E */
359 #define MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER 47 /* 0x2F */
360 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_CA 48 /* 0x30 */
361 #define MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED 49 /* 0x31 */
362 #define MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR 50 /* 0x32 */
363 #define MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR 51 /* 0x33 */
364 #define MBEDTLS_SSL_ALERT_MSG_EXPORT_RESTRICTION 60 /* 0x3C */
365 #define MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION 70 /* 0x46 */
366 #define MBEDTLS_SSL_ALERT_MSG_INSUFFICIENT_SECURITY 71 /* 0x47 */
367 #define MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR 80 /* 0x50 */
368 #define MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK 86 /* 0x56 */
369 #define MBEDTLS_SSL_ALERT_MSG_USER_CANCELED 90 /* 0x5A */
370 #define MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION 100 /* 0x64 */
371 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT 110 /* 0x6E */
372 #define MBEDTLS_SSL_ALERT_MSG_UNRECOGNIZED_NAME 112 /* 0x70 */
373 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY 115 /* 0x73 */
374 #define MBEDTLS_SSL_ALERT_MSG_NO_APPLICATION_PROTOCOL 120 /* 0x78 */
375
376 #define MBEDTLS_SSL_HS_HELLO_REQUEST 0
377 #define MBEDTLS_SSL_HS_CLIENT_HELLO 1
378 #define MBEDTLS_SSL_HS_SERVER_HELLO 2
379 #define MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST 3
380 #define MBEDTLS_SSL_HS_NEW_SESSION_TICKET 4
381 #define MBEDTLS_SSL_HS_CERTIFICATE 11
382 #define MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE 12
383 #define MBEDTLS_SSL_HS_CERTIFICATE_REQUEST 13
384 #define MBEDTLS_SSL_HS_SERVER_HELLO_DONE 14
385 #define MBEDTLS_SSL_HS_CERTIFICATE_VERIFY 15
386 #define MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE 16
387 #define MBEDTLS_SSL_HS_FINISHED 20
388
389 /*
390 * TLS extensions
391 */
392 #define MBEDTLS_TLS_EXT_SERVERNAME 0
393 #define MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME 0
394
395 #define MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH 1
396
397 #define MBEDTLS_TLS_EXT_TRUNCATED_HMAC 4
398
399 #define MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES 10
400 #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS 11
401
402 #define MBEDTLS_TLS_EXT_SIG_ALG 13
403
404 #define MBEDTLS_TLS_EXT_USE_SRTP 14
405
406 #define MBEDTLS_TLS_EXT_ALPN 16
407
408 #define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC 22 /* 0x16 */
409 #define MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET 0x0017 /* 23 */
410
411 #define MBEDTLS_TLS_EXT_SESSION_TICKET 35
412
413 /* The value of the CID extension is still TBD as of
414 * draft-ietf-tls-dtls-connection-id-05
415 * (https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05) */
416 #define MBEDTLS_TLS_EXT_CID 254 /* TBD */
417
418 #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP 256 /* experimental */
419
420 #define MBEDTLS_TLS_EXT_RENEGOTIATION_INFO 0xFF01
421
422 /*
423 * Size defines
424 */
425 #if !defined(MBEDTLS_PSK_MAX_LEN)
426 #define MBEDTLS_PSK_MAX_LEN 32 /* 256 bits */
427 #endif
428
429 /* Dummy type used only for its size */
430 union mbedtls_ssl_premaster_secret
431 {
432 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
433 unsigned char _pms_rsa[48]; /* RFC 5246 8.1.1 */
434 #endif
435 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)
436 unsigned char _pms_dhm[MBEDTLS_MPI_MAX_SIZE]; /* RFC 5246 8.1.2 */
437 #endif
438 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
439 defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
440 defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
441 defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
442 unsigned char _pms_ecdh[MBEDTLS_ECP_MAX_BYTES]; /* RFC 4492 5.10 */
443 #endif
444 #if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
445 unsigned char _pms_psk[4 + 2 * MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 2 */
446 #endif
447 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
448 unsigned char _pms_dhe_psk[4 + MBEDTLS_MPI_MAX_SIZE
449 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 3 */
450 #endif
451 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
452 unsigned char _pms_rsa_psk[52 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 4 */
453 #endif
454 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
455 unsigned char _pms_ecdhe_psk[4 + MBEDTLS_ECP_MAX_BYTES
456 + MBEDTLS_PSK_MAX_LEN]; /* RFC 5489 2 */
457 #endif
458 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
459 unsigned char _pms_ecjpake[32]; /* Thread spec: SHA-256 output */
460 #endif
461 };
462
463 #define MBEDTLS_PREMASTER_SIZE sizeof( union mbedtls_ssl_premaster_secret )
464
465 #ifdef __cplusplus
466 extern "C" {
467 #endif
468
469 /*
470 * SSL state machine
471 */
472 typedef enum
473 {
474 MBEDTLS_SSL_HELLO_REQUEST,
475 MBEDTLS_SSL_CLIENT_HELLO,
476 MBEDTLS_SSL_SERVER_HELLO,
477 MBEDTLS_SSL_SERVER_CERTIFICATE,
478 MBEDTLS_SSL_SERVER_KEY_EXCHANGE,
479 MBEDTLS_SSL_CERTIFICATE_REQUEST,
480 MBEDTLS_SSL_SERVER_HELLO_DONE,
481 MBEDTLS_SSL_CLIENT_CERTIFICATE,
482 MBEDTLS_SSL_CLIENT_KEY_EXCHANGE,
483 MBEDTLS_SSL_CERTIFICATE_VERIFY,
484 MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC,
485 MBEDTLS_SSL_CLIENT_FINISHED,
486 MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC,
487 MBEDTLS_SSL_SERVER_FINISHED,
488 MBEDTLS_SSL_FLUSH_BUFFERS,
489 MBEDTLS_SSL_HANDSHAKE_WRAPUP,
490 MBEDTLS_SSL_HANDSHAKE_OVER,
491 MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET,
492 MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT,
493 }
494 mbedtls_ssl_states;
495
496 /*
497 * The tls_prf function types.
498 */
499 typedef enum
500 {
501 MBEDTLS_SSL_TLS_PRF_NONE,
502 MBEDTLS_SSL_TLS_PRF_SSL3,
503 MBEDTLS_SSL_TLS_PRF_TLS1,
504 MBEDTLS_SSL_TLS_PRF_SHA384,
505 MBEDTLS_SSL_TLS_PRF_SHA256
506 }
507 mbedtls_tls_prf_types;
508 /**
509 * \brief Callback type: send data on the network.
510 *
511 * \note That callback may be either blocking or non-blocking.
512 *
513 * \param ctx Context for the send callback (typically a file descriptor)
514 * \param buf Buffer holding the data to send
515 * \param len Length of the data to send
516 *
517 * \return The callback must return the number of bytes sent if any,
518 * or a non-zero error code.
519 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_WRITE
520 * must be returned when the operation would block.
521 *
522 * \note The callback is allowed to send fewer bytes than requested.
523 * It must always return the number of bytes actually sent.
524 */
525 typedef int mbedtls_ssl_send_t( void *ctx,
526 const unsigned char *buf,
527 size_t len );
528
529 /**
530 * \brief Callback type: receive data from the network.
531 *
532 * \note That callback may be either blocking or non-blocking.
533 *
534 * \param ctx Context for the receive callback (typically a file
535 * descriptor)
536 * \param buf Buffer to write the received data to
537 * \param len Length of the receive buffer
538 *
539 * \return The callback must return the number of bytes received,
540 * or a non-zero error code.
541 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ
542 * must be returned when the operation would block.
543 *
544 * \note The callback may receive fewer bytes than the length of the
545 * buffer. It must always return the number of bytes actually
546 * received and written to the buffer.
547 */
548 typedef int mbedtls_ssl_recv_t( void *ctx,
549 unsigned char *buf,
550 size_t len );
551
552 /**
553 * \brief Callback type: receive data from the network, with timeout
554 *
555 * \note That callback must block until data is received, or the
556 * timeout delay expires, or the operation is interrupted by a
557 * signal.
558 *
559 * \param ctx Context for the receive callback (typically a file descriptor)
560 * \param buf Buffer to write the received data to
561 * \param len Length of the receive buffer
562 * \param timeout Maximum nomber of millisecondes to wait for data
563 * 0 means no timeout (potentially waiting forever)
564 *
565 * \return The callback must return the number of bytes received,
566 * or a non-zero error code:
567 * \c MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out,
568 * \c MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal.
569 *
570 * \note The callback may receive fewer bytes than the length of the
571 * buffer. It must always return the number of bytes actually
572 * received and written to the buffer.
573 */
574 typedef int mbedtls_ssl_recv_timeout_t( void *ctx,
575 unsigned char *buf,
576 size_t len,
577 uint32_t timeout );
578 /**
579 * \brief Callback type: set a pair of timers/delays to watch
580 *
581 * \param ctx Context pointer
582 * \param int_ms Intermediate delay in milliseconds
583 * \param fin_ms Final delay in milliseconds
584 * 0 cancels the current timer.
585 *
586 * \note This callback must at least store the necessary information
587 * for the associated \c mbedtls_ssl_get_timer_t callback to
588 * return correct information.
589 *
590 * \note If using a event-driven style of programming, an event must
591 * be generated when the final delay is passed. The event must
592 * cause a call to \c mbedtls_ssl_handshake() with the proper
593 * SSL context to be scheduled. Care must be taken to ensure
594 * that at most one such call happens at a time.
595 *
596 * \note Only one timer at a time must be running. Calling this
597 * function while a timer is running must cancel it. Cancelled
598 * timers must not generate any event.
599 */
600 typedef void mbedtls_ssl_set_timer_t( void * ctx,
601 uint32_t int_ms,
602 uint32_t fin_ms );
603
604 /**
605 * \brief Callback type: get status of timers/delays
606 *
607 * \param ctx Context pointer
608 *
609 * \return This callback must return:
610 * -1 if cancelled (fin_ms == 0),
611 * 0 if none of the delays have passed,
612 * 1 if only the intermediate delay has passed,
613 * 2 if the final delay has passed.
614 */
615 typedef int mbedtls_ssl_get_timer_t( void * ctx );
616
617 /* Defined below */
618 typedef struct mbedtls_ssl_session mbedtls_ssl_session;
619 typedef struct mbedtls_ssl_context mbedtls_ssl_context;
620 typedef struct mbedtls_ssl_config mbedtls_ssl_config;
621
622 /* Defined in ssl_internal.h */
623 typedef struct mbedtls_ssl_transform mbedtls_ssl_transform;
624 typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params;
625 typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t;
626 #if defined(MBEDTLS_X509_CRT_PARSE_C)
627 typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert;
628 #endif
629 #if defined(MBEDTLS_SSL_PROTO_DTLS)
630 typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item;
631 #endif
632
633 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
634 #if defined(MBEDTLS_X509_CRT_PARSE_C)
635 /**
636 * \brief Callback type: start external signature operation.
637 *
638 * This callback is called during an SSL handshake to start
639 * a signature decryption operation using an
640 * external processor. The parameter \p cert contains
641 * the public key; it is up to the callback function to
642 * determine how to access the associated private key.
643 *
644 * This function typically sends or enqueues a request, and
645 * does not wait for the operation to complete. This allows
646 * the handshake step to be non-blocking.
647 *
648 * The parameters \p ssl and \p cert are guaranteed to remain
649 * valid throughout the handshake. On the other hand, this
650 * function must save the contents of \p hash if the value
651 * is needed for later processing, because the \p hash buffer
652 * is no longer valid after this function returns.
653 *
654 * This function may call mbedtls_ssl_set_async_operation_data()
655 * to store an operation context for later retrieval
656 * by the resume or cancel callback.
657 *
658 * \note For RSA signatures, this function must produce output
659 * that is consistent with PKCS#1 v1.5 in the same way as
660 * mbedtls_rsa_pkcs1_sign(). Before the private key operation,
661 * apply the padding steps described in RFC 8017, section 9.2
662 * "EMSA-PKCS1-v1_5" as follows.
663 * - If \p md_alg is #MBEDTLS_MD_NONE, apply the PKCS#1 v1.5
664 * encoding, treating \p hash as the DigestInfo to be
665 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
666 * from step 3, with `T = hash` and `tLen = hash_len`.
667 * - If `md_alg != MBEDTLS_MD_NONE`, apply the PKCS#1 v1.5
668 * encoding, treating \p hash as the hash to be encoded and
669 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
670 * from step 2, with `digestAlgorithm` obtained by calling
671 * mbedtls_oid_get_oid_by_md() on \p md_alg.
672 *
673 * \note For ECDSA signatures, the output format is the DER encoding
674 * `Ecdsa-Sig-Value` defined in
675 * [RFC 4492 section 5.4](https://tools.ietf.org/html/rfc4492#section-5.4).
676 *
677 * \param ssl The SSL connection instance. It should not be
678 * modified other than via
679 * mbedtls_ssl_set_async_operation_data().
680 * \param cert Certificate containing the public key.
681 * In simple cases, this is one of the pointers passed to
682 * mbedtls_ssl_conf_own_cert() when configuring the SSL
683 * connection. However, if other callbacks are used, this
684 * property may not hold. For example, if an SNI callback
685 * is registered with mbedtls_ssl_conf_sni(), then
686 * this callback determines what certificate is used.
687 * \param md_alg Hash algorithm.
688 * \param hash Buffer containing the hash. This buffer is
689 * no longer valid when the function returns.
690 * \param hash_len Size of the \c hash buffer in bytes.
691 *
692 * \return 0 if the operation was started successfully and the SSL
693 * stack should call the resume callback immediately.
694 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
695 * was started successfully and the SSL stack should return
696 * immediately without calling the resume callback yet.
697 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
698 * processor does not support this key. The SSL stack will
699 * use the private key object instead.
700 * \return Any other error indicates a fatal failure and is
701 * propagated up the call chain. The callback should
702 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
703 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
704 * directed in the documentation of this callback.
705 */
706 typedef int mbedtls_ssl_async_sign_t( mbedtls_ssl_context *ssl,
707 mbedtls_x509_crt *cert,
708 mbedtls_md_type_t md_alg,
709 const unsigned char *hash,
710 size_t hash_len );
711
712 /**
713 * \brief Callback type: start external decryption operation.
714 *
715 * This callback is called during an SSL handshake to start
716 * an RSA decryption operation using an
717 * external processor. The parameter \p cert contains
718 * the public key; it is up to the callback function to
719 * determine how to access the associated private key.
720 *
721 * This function typically sends or enqueues a request, and
722 * does not wait for the operation to complete. This allows
723 * the handshake step to be non-blocking.
724 *
725 * The parameters \p ssl and \p cert are guaranteed to remain
726 * valid throughout the handshake. On the other hand, this
727 * function must save the contents of \p input if the value
728 * is needed for later processing, because the \p input buffer
729 * is no longer valid after this function returns.
730 *
731 * This function may call mbedtls_ssl_set_async_operation_data()
732 * to store an operation context for later retrieval
733 * by the resume or cancel callback.
734 *
735 * \warning RSA decryption as used in TLS is subject to a potential
736 * timing side channel attack first discovered by Bleichenbacher
737 * in 1998. This attack can be remotely exploitable
738 * in practice. To avoid this attack, you must ensure that
739 * if the callback performs an RSA decryption, the time it
740 * takes to execute and return the result does not depend
741 * on whether the RSA decryption succeeded or reported
742 * invalid padding.
743 *
744 * \param ssl The SSL connection instance. It should not be
745 * modified other than via
746 * mbedtls_ssl_set_async_operation_data().
747 * \param cert Certificate containing the public key.
748 * In simple cases, this is one of the pointers passed to
749 * mbedtls_ssl_conf_own_cert() when configuring the SSL
750 * connection. However, if other callbacks are used, this
751 * property may not hold. For example, if an SNI callback
752 * is registered with mbedtls_ssl_conf_sni(), then
753 * this callback determines what certificate is used.
754 * \param input Buffer containing the input ciphertext. This buffer
755 * is no longer valid when the function returns.
756 * \param input_len Size of the \p input buffer in bytes.
757 *
758 * \return 0 if the operation was started successfully and the SSL
759 * stack should call the resume callback immediately.
760 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
761 * was started successfully and the SSL stack should return
762 * immediately without calling the resume callback yet.
763 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
764 * processor does not support this key. The SSL stack will
765 * use the private key object instead.
766 * \return Any other error indicates a fatal failure and is
767 * propagated up the call chain. The callback should
768 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
769 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
770 * directed in the documentation of this callback.
771 */
772 typedef int mbedtls_ssl_async_decrypt_t( mbedtls_ssl_context *ssl,
773 mbedtls_x509_crt *cert,
774 const unsigned char *input,
775 size_t input_len );
776 #endif /* MBEDTLS_X509_CRT_PARSE_C */
777
778 /**
779 * \brief Callback type: resume external operation.
780 *
781 * This callback is called during an SSL handshake to resume
782 * an external operation started by the
783 * ::mbedtls_ssl_async_sign_t or
784 * ::mbedtls_ssl_async_decrypt_t callback.
785 *
786 * This function typically checks the status of a pending
787 * request or causes the request queue to make progress, and
788 * does not wait for the operation to complete. This allows
789 * the handshake step to be non-blocking.
790 *
791 * This function may call mbedtls_ssl_get_async_operation_data()
792 * to retrieve an operation context set by the start callback.
793 * It may call mbedtls_ssl_set_async_operation_data() to modify
794 * this context.
795 *
796 * Note that when this function returns a status other than
797 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, it must free any
798 * resources associated with the operation.
799 *
800 * \param ssl The SSL connection instance. It should not be
801 * modified other than via
802 * mbedtls_ssl_set_async_operation_data().
803 * \param output Buffer containing the output (signature or decrypted
804 * data) on success.
805 * \param output_len On success, number of bytes written to \p output.
806 * \param output_size Size of the \p output buffer in bytes.
807 *
808 * \return 0 if output of the operation is available in the
809 * \p output buffer.
810 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
811 * is still in progress. Subsequent requests for progress
812 * on the SSL connection will call the resume callback
813 * again.
814 * \return Any other error means that the operation is aborted.
815 * The SSL handshake is aborted. The callback should
816 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
817 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
818 * directed in the documentation of this callback.
819 */
820 typedef int mbedtls_ssl_async_resume_t( mbedtls_ssl_context *ssl,
821 unsigned char *output,
822 size_t *output_len,
823 size_t output_size );
824
825 /**
826 * \brief Callback type: cancel external operation.
827 *
828 * This callback is called if an SSL connection is closed
829 * while an asynchronous operation is in progress. Note that
830 * this callback is not called if the
831 * ::mbedtls_ssl_async_resume_t callback has run and has
832 * returned a value other than
833 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, since in that case
834 * the asynchronous operation has already completed.
835 *
836 * This function may call mbedtls_ssl_get_async_operation_data()
837 * to retrieve an operation context set by the start callback.
838 *
839 * \param ssl The SSL connection instance. It should not be
840 * modified.
841 */
842 typedef void mbedtls_ssl_async_cancel_t( mbedtls_ssl_context *ssl );
843 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
844
845 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) && \
846 !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
847 #define MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN 48
848 #if defined(MBEDTLS_SHA256_C)
849 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA256
850 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 32
851 #elif defined(MBEDTLS_SHA512_C)
852 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA384
853 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 48
854 #elif defined(MBEDTLS_SHA1_C)
855 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA1
856 #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 20
857 #else
858 /* This is already checked in check_config.h, but be sure. */
859 #error "Bad configuration - need SHA-1, SHA-256 or SHA-512 enabled to compute digest of peer CRT."
860 #endif
861 #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED &&
862 !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
863
864 #if defined(MBEDTLS_SSL_DTLS_SRTP)
865
866 #define MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH 255
867 #define MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH 4
868 /*
869 * For code readability use a typedef for DTLS-SRTP profiles
870 *
871 * Use_srtp extension protection profiles values as defined in
872 * http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
873 *
874 * Reminder: if this list is expanded mbedtls_ssl_check_srtp_profile_value
875 * must be updated too.
876 */
877 #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80 ( (uint16_t) 0x0001)
878 #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32 ( (uint16_t) 0x0002)
879 #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80 ( (uint16_t) 0x0005)
880 #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32 ( (uint16_t) 0x0006)
881 /* This one is not iana defined, but for code readability. */
882 #define MBEDTLS_TLS_SRTP_UNSET ( (uint16_t) 0x0000)
883
884 typedef uint16_t mbedtls_ssl_srtp_profile;
885
886 typedef struct mbedtls_dtls_srtp_info_t
887 {
888 /*! The SRTP profile that was negotiated. */
889 mbedtls_ssl_srtp_profile chosen_dtls_srtp_profile;
890 /*! The length of mki_value. */
891 uint16_t mki_len;
892 /*! The mki_value used, with max size of 256 bytes. */
893 unsigned char mki_value[MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH];
894 }
895 mbedtls_dtls_srtp_info;
896
897 #endif /* MBEDTLS_SSL_DTLS_SRTP */
898
899 /*
900 * This structure is used for storing current session data.
901 *
902 * Note: when changing this definition, we need to check and update:
903 * - in tests/suites/test_suite_ssl.function:
904 * ssl_populate_session() and ssl_serialize_session_save_load()
905 * - in library/ssl_tls.c:
906 * mbedtls_ssl_session_init() and mbedtls_ssl_session_free()
907 * mbedtls_ssl_session_save() and ssl_session_load()
908 * ssl_session_copy()
909 */
910 struct mbedtls_ssl_session
911 {
912 #if defined(MBEDTLS_HAVE_TIME)
913 mbedtls_time_t start; /*!< starting time */
914 #endif
915 int ciphersuite; /*!< chosen ciphersuite */
916 int compression; /*!< chosen compression */
917 size_t id_len; /*!< session id length */
918 unsigned char id[32]; /*!< session identifier */
919 unsigned char master[48]; /*!< the master secret */
920
921 #if defined(MBEDTLS_X509_CRT_PARSE_C)
922 #if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
923 mbedtls_x509_crt *peer_cert; /*!< peer X.509 cert chain */
924 #else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
925 /*! The digest of the peer's end-CRT. This must be kept to detect CRT
926 * changes during renegotiation, mitigating the triple handshake attack. */
927 unsigned char *peer_cert_digest;
928 size_t peer_cert_digest_len;
929 mbedtls_md_type_t peer_cert_digest_type;
930 #endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
931 #endif /* MBEDTLS_X509_CRT_PARSE_C */
932 uint32_t verify_result; /*!< verification result */
933
934 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
935 unsigned char *ticket; /*!< RFC 5077 session ticket */
936 size_t ticket_len; /*!< session ticket length */
937 uint32_t ticket_lifetime; /*!< ticket lifetime hint */
938 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
939
940 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
941 unsigned char mfl_code; /*!< MaxFragmentLength negotiated by peer */
942 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
943
944 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
945 int trunc_hmac; /*!< flag for truncated hmac activation */
946 #endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
947
948 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
949 int encrypt_then_mac; /*!< flag for EtM activation */
950 #endif
951 };
952
953 /**
954 * SSL/TLS configuration to be shared between mbedtls_ssl_context structures.
955 */
956 struct mbedtls_ssl_config
957 {
958 /* Group items by size (largest first) to minimize padding overhead */
959
960 /*
961 * Pointers
962 */
963
964 const int *ciphersuite_list[4]; /*!< allowed ciphersuites per version */
965
966 /** Callback for printing debug output */
967 void (*f_dbg)(void *, int, const char *, int, const char *);
968 void *p_dbg; /*!< context for the debug function */
969
970 /** Callback for getting (pseudo-)random numbers */
971 int (*f_rng)(void *, unsigned char *, size_t);
972 void *p_rng; /*!< context for the RNG function */
973
974 /** Callback to retrieve a session from the cache */
975 int (*f_get_cache)(void *, mbedtls_ssl_session *);
976 /** Callback to store a session into the cache */
977 int (*f_set_cache)(void *, const mbedtls_ssl_session *);
978 void *p_cache; /*!< context for cache callbacks */
979
980 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
981 /** Callback for setting cert according to SNI extension */
982 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
983 void *p_sni; /*!< context for SNI callback */
984 #endif
985
986 #if defined(MBEDTLS_X509_CRT_PARSE_C)
987 /** Callback to customize X.509 certificate chain verification */
988 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *);
989 void *p_vrfy; /*!< context for X.509 verify calllback */
990 #endif
991
992 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
993 /** Callback to retrieve PSK key from identity */
994 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
995 void *p_psk; /*!< context for PSK callback */
996 #endif
997
998 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
999 /** Callback to create & write a cookie for ClientHello veirifcation */
1000 int (*f_cookie_write)( void *, unsigned char **, unsigned char *,
1001 const unsigned char *, size_t );
1002 /** Callback to verify validity of a ClientHello cookie */
1003 int (*f_cookie_check)( void *, const unsigned char *, size_t,
1004 const unsigned char *, size_t );
1005 void *p_cookie; /*!< context for the cookie callbacks */
1006 #endif
1007
1008 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
1009 /** Callback to create & write a session ticket */
1010 int (*f_ticket_write)( void *, const mbedtls_ssl_session *,
1011 unsigned char *, const unsigned char *, size_t *, uint32_t * );
1012 /** Callback to parse a session ticket into a session structure */
1013 int (*f_ticket_parse)( void *, mbedtls_ssl_session *, unsigned char *, size_t);
1014 void *p_ticket; /*!< context for the ticket callbacks */
1015 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
1016
1017 #if defined(MBEDTLS_SSL_EXPORT_KEYS)
1018 /** Callback to export key block and master secret */
1019 int (*f_export_keys)( void *, const unsigned char *,
1020 const unsigned char *, size_t, size_t, size_t );
1021 /** Callback to export key block, master secret,
1022 * tls_prf and random bytes. Should replace f_export_keys */
1023 int (*f_export_keys_ext)( void *, const unsigned char *,
1024 const unsigned char *, size_t, size_t, size_t,
1025 const unsigned char[32], const unsigned char[32],
1026 mbedtls_tls_prf_types );
1027 void *p_export_keys; /*!< context for key export callback */
1028 #endif
1029
1030 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1031 size_t cid_len; /*!< The length of CIDs for incoming DTLS records. */
1032 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1033
1034 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1035 const mbedtls_x509_crt_profile *cert_profile; /*!< verification profile */
1036 mbedtls_ssl_key_cert *key_cert; /*!< own certificate/key pair(s) */
1037 mbedtls_x509_crt *ca_chain; /*!< trusted CAs */
1038 mbedtls_x509_crl *ca_crl; /*!< trusted CAs CRLs */
1039 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
1040 mbedtls_x509_crt_ca_cb_t f_ca_cb;
1041 void *p_ca_cb;
1042 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
1043 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1044
1045 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
1046 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1047 mbedtls_ssl_async_sign_t *f_async_sign_start; /*!< start asynchronous signature operation */
1048 mbedtls_ssl_async_decrypt_t *f_async_decrypt_start; /*!< start asynchronous decryption operation */
1049 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1050 mbedtls_ssl_async_resume_t *f_async_resume; /*!< resume asynchronous operation */
1051 mbedtls_ssl_async_cancel_t *f_async_cancel; /*!< cancel asynchronous operation */
1052 void *p_async_config_data; /*!< Configuration data set by mbedtls_ssl_conf_async_private_cb(). */
1053 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1054
1055 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
1056 const int *sig_hashes; /*!< allowed signature hashes */
1057 #endif
1058
1059 #if defined(MBEDTLS_ECP_C)
1060 const mbedtls_ecp_group_id *curve_list; /*!< allowed curves */
1061 #endif
1062
1063 #if defined(MBEDTLS_DHM_C)
1064 mbedtls_mpi dhm_P; /*!< prime modulus for DHM */
1065 mbedtls_mpi dhm_G; /*!< generator for DHM */
1066 #endif
1067
1068 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
1069
1070 #if defined(MBEDTLS_USE_PSA_CRYPTO)
1071 psa_key_id_t psk_opaque; /*!< PSA key slot holding opaque PSK. This field
1072 * should only be set via
1073 * mbedtls_ssl_conf_psk_opaque().
1074 * If either no PSK or a raw PSK have been
1075 * configured, this has value \c 0.
1076 */
1077 #endif /* MBEDTLS_USE_PSA_CRYPTO */
1078
1079 unsigned char *psk; /*!< The raw pre-shared key. This field should
1080 * only be set via mbedtls_ssl_conf_psk().
1081 * If either no PSK or an opaque PSK
1082 * have been configured, this has value NULL. */
1083 size_t psk_len; /*!< The length of the raw pre-shared key.
1084 * This field should only be set via
1085 * mbedtls_ssl_conf_psk().
1086 * Its value is non-zero if and only if
1087 * \c psk is not \c NULL. */
1088
1089 unsigned char *psk_identity; /*!< The PSK identity for PSK negotiation.
1090 * This field should only be set via
1091 * mbedtls_ssl_conf_psk().
1092 * This is set if and only if either
1093 * \c psk or \c psk_opaque are set. */
1094 size_t psk_identity_len;/*!< The length of PSK identity.
1095 * This field should only be set via
1096 * mbedtls_ssl_conf_psk().
1097 * Its value is non-zero if and only if
1098 * \c psk is not \c NULL or \c psk_opaque
1099 * is not \c 0. */
1100 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
1101
1102 #if defined(MBEDTLS_SSL_ALPN)
1103 const char **alpn_list; /*!< ordered list of protocols */
1104 #endif
1105
1106 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1107 /*! ordered list of supported srtp profile */
1108 const mbedtls_ssl_srtp_profile *dtls_srtp_profile_list;
1109 /*! number of supported profiles */
1110 size_t dtls_srtp_profile_list_len;
1111 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1112
1113 /*
1114 * Numerical settings (int then char)
1115 */
1116
1117 uint32_t read_timeout; /*!< timeout for mbedtls_ssl_read (ms) */
1118
1119 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1120 uint32_t hs_timeout_min; /*!< initial value of the handshake
1121 retransmission timeout (ms) */
1122 uint32_t hs_timeout_max; /*!< maximum value of the handshake
1123 retransmission timeout (ms) */
1124 #endif
1125
1126 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1127 int renego_max_records; /*!< grace period for renegotiation */
1128 unsigned char renego_period[8]; /*!< value of the record counters
1129 that triggers renegotiation */
1130 #endif
1131
1132 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
1133 unsigned int badmac_limit; /*!< limit of records with a bad MAC */
1134 #endif
1135
1136 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
1137 unsigned int dhm_min_bitlen; /*!< min. bit length of the DHM prime */
1138 #endif
1139
1140 unsigned char max_major_ver; /*!< max. major version used */
1141 unsigned char max_minor_ver; /*!< max. minor version used */
1142 unsigned char min_major_ver; /*!< min. major version used */
1143 unsigned char min_minor_ver; /*!< min. minor version used */
1144
1145 /*
1146 * Flags (bitfields)
1147 */
1148
1149 unsigned int endpoint : 1; /*!< 0: client, 1: server */
1150 unsigned int transport : 1; /*!< stream (TLS) or datagram (DTLS) */
1151 unsigned int authmode : 2; /*!< MBEDTLS_SSL_VERIFY_XXX */
1152 /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE */
1153 unsigned int allow_legacy_renegotiation : 2 ; /*!< MBEDTLS_LEGACY_XXX */
1154 #if defined(MBEDTLS_ARC4_C)
1155 unsigned int arc4_disabled : 1; /*!< blacklist RC4 ciphersuites? */
1156 #endif
1157 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
1158 unsigned int mfl_code : 3; /*!< desired fragment length */
1159 #endif
1160 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1161 unsigned int encrypt_then_mac : 1 ; /*!< negotiate encrypt-then-mac? */
1162 #endif
1163 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
1164 unsigned int extended_ms : 1; /*!< negotiate extended master secret? */
1165 #endif
1166 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1167 unsigned int anti_replay : 1; /*!< detect and prevent replay? */
1168 #endif
1169 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
1170 unsigned int cbc_record_splitting : 1; /*!< do cbc record splitting */
1171 #endif
1172 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1173 unsigned int disable_renegotiation : 1; /*!< disable renegotiation? */
1174 #endif
1175 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
1176 unsigned int trunc_hmac : 1; /*!< negotiate truncated hmac? */
1177 #endif
1178 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
1179 unsigned int session_tickets : 1; /*!< use session tickets? */
1180 #endif
1181 #if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C)
1182 unsigned int fallback : 1; /*!< is this a fallback? */
1183 #endif
1184 #if defined(MBEDTLS_SSL_SRV_C)
1185 unsigned int cert_req_ca_list : 1; /*!< enable sending CA list in
1186 Certificate Request messages? */
1187 #endif
1188 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1189 unsigned int ignore_unexpected_cid : 1; /*!< Determines whether DTLS
1190 * record with unexpected CID
1191 * should lead to failure. */
1192 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1193 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1194 unsigned int dtls_srtp_mki_support : 1; /* support having mki_value
1195 in the use_srtp extension */
1196 #endif
1197 };
1198
1199 struct mbedtls_ssl_context
1200 {
1201 const mbedtls_ssl_config *conf; /*!< configuration information */
1202
1203 /*
1204 * Miscellaneous
1205 */
1206 int state; /*!< SSL handshake: current state */
1207 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1208 int renego_status; /*!< Initial, in progress, pending? */
1209 int renego_records_seen; /*!< Records since renego request, or with DTLS,
1210 number of retransmissions of request if
1211 renego_max_records is < 0 */
1212 #endif /* MBEDTLS_SSL_RENEGOTIATION */
1213
1214 int major_ver; /*!< equal to MBEDTLS_SSL_MAJOR_VERSION_3 */
1215 int minor_ver; /*!< either 0 (SSL3) or 1 (TLS1.0) */
1216
1217 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
1218 unsigned badmac_seen; /*!< records with a bad MAC received */
1219 #endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */
1220
1221 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1222 /** Callback to customize X.509 certificate chain verification */
1223 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *);
1224 void *p_vrfy; /*!< context for X.509 verify callback */
1225 #endif
1226
1227 mbedtls_ssl_send_t *f_send; /*!< Callback for network send */
1228 mbedtls_ssl_recv_t *f_recv; /*!< Callback for network receive */
1229 mbedtls_ssl_recv_timeout_t *f_recv_timeout;
1230 /*!< Callback for network receive with timeout */
1231
1232 void *p_bio; /*!< context for I/O operations */
1233
1234 /*
1235 * Session layer
1236 */
1237 mbedtls_ssl_session *session_in; /*!< current session data (in) */
1238 mbedtls_ssl_session *session_out; /*!< current session data (out) */
1239 mbedtls_ssl_session *session; /*!< negotiated session data */
1240 mbedtls_ssl_session *session_negotiate; /*!< session data in negotiation */
1241
1242 mbedtls_ssl_handshake_params *handshake; /*!< params required only during
1243 the handshake process */
1244
1245 /*
1246 * Record layer transformations
1247 */
1248 mbedtls_ssl_transform *transform_in; /*!< current transform params (in) */
1249 mbedtls_ssl_transform *transform_out; /*!< current transform params (in) */
1250 mbedtls_ssl_transform *transform; /*!< negotiated transform params */
1251 mbedtls_ssl_transform *transform_negotiate; /*!< transform params in negotiation */
1252
1253 /*
1254 * Timers
1255 */
1256 void *p_timer; /*!< context for the timer callbacks */
1257
1258 mbedtls_ssl_set_timer_t *f_set_timer; /*!< set timer callback */
1259 mbedtls_ssl_get_timer_t *f_get_timer; /*!< get timer callback */
1260
1261 /*
1262 * Record layer (incoming data)
1263 */
1264 unsigned char *in_buf; /*!< input buffer */
1265 unsigned char *in_ctr; /*!< 64-bit incoming message counter
1266 TLS: maintained by us
1267 DTLS: read from peer */
1268 unsigned char *in_hdr; /*!< start of record header */
1269 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1270 unsigned char *in_cid; /*!< The start of the CID;
1271 * (the end is marked by in_len). */
1272 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1273 unsigned char *in_len; /*!< two-bytes message length field */
1274 unsigned char *in_iv; /*!< ivlen-byte IV */
1275 unsigned char *in_msg; /*!< message contents (in_iv+ivlen) */
1276 unsigned char *in_offt; /*!< read offset in application data */
1277
1278 int in_msgtype; /*!< record header: message type */
1279 size_t in_msglen; /*!< record header: message length */
1280 size_t in_left; /*!< amount of data read so far */
1281 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1282 size_t in_buf_len; /*!< length of input buffer */
1283 #endif
1284 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1285 uint16_t in_epoch; /*!< DTLS epoch for incoming records */
1286 size_t next_record_offset; /*!< offset of the next record in datagram
1287 (equal to in_left if none) */
1288 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1289 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1290 uint64_t in_window_top; /*!< last validated record seq_num */
1291 uint64_t in_window; /*!< bitmask for replay detection */
1292 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
1293
1294 size_t in_hslen; /*!< current handshake message length,
1295 including the handshake header */
1296 int nb_zero; /*!< # of 0-length encrypted messages */
1297
1298 int keep_current_message; /*!< drop or reuse current message
1299 on next call to record layer? */
1300
1301 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1302 uint8_t disable_datagram_packing; /*!< Disable packing multiple records
1303 * within a single datagram. */
1304 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1305
1306 /*
1307 * Record layer (outgoing data)
1308 */
1309 unsigned char *out_buf; /*!< output buffer */
1310 unsigned char *out_ctr; /*!< 64-bit outgoing message counter */
1311 unsigned char *out_hdr; /*!< start of record header */
1312 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1313 unsigned char *out_cid; /*!< The start of the CID;
1314 * (the end is marked by in_len). */
1315 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1316 unsigned char *out_len; /*!< two-bytes message length field */
1317 unsigned char *out_iv; /*!< ivlen-byte IV */
1318 unsigned char *out_msg; /*!< message contents (out_iv+ivlen) */
1319
1320 int out_msgtype; /*!< record header: message type */
1321 size_t out_msglen; /*!< record header: message length */
1322 size_t out_left; /*!< amount of data not yet written */
1323 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1324 size_t out_buf_len; /*!< length of output buffer */
1325 #endif
1326
1327 unsigned char cur_out_ctr[8]; /*!< Outgoing record sequence number. */
1328
1329 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1330 uint16_t mtu; /*!< path mtu, used to fragment outgoing messages */
1331 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1332
1333 #if defined(MBEDTLS_ZLIB_SUPPORT)
1334 unsigned char *compress_buf; /*!< zlib data buffer */
1335 #endif /* MBEDTLS_ZLIB_SUPPORT */
1336 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
1337 signed char split_done; /*!< current record already splitted? */
1338 #endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */
1339
1340 /*
1341 * PKI layer
1342 */
1343 int client_auth; /*!< flag for client auth. */
1344
1345 /*
1346 * User settings
1347 */
1348 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1349 char *hostname; /*!< expected peer CN for verification
1350 (and SNI if available) */
1351 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1352
1353 #if defined(MBEDTLS_SSL_ALPN)
1354 const char *alpn_chosen; /*!< negotiated protocol */
1355 #endif /* MBEDTLS_SSL_ALPN */
1356
1357 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1358 /*
1359 * use_srtp extension
1360 */
1361 mbedtls_dtls_srtp_info dtls_srtp_info;
1362 #endif /* MBEDTLS_SSL_DTLS_SRTP */
1363
1364 /*
1365 * Information for DTLS hello verify
1366 */
1367 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1368 unsigned char *cli_id; /*!< transport-level ID of the client */
1369 size_t cli_id_len; /*!< length of cli_id */
1370 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
1371
1372 /*
1373 * Secure renegotiation
1374 */
1375 /* needed to know when to send extension on server */
1376 int secure_renegotiation; /*!< does peer support legacy or
1377 secure renegotiation */
1378 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1379 size_t verify_data_len; /*!< length of verify data stored */
1380 char own_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
1381 char peer_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
1382 #endif /* MBEDTLS_SSL_RENEGOTIATION */
1383
1384 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1385 /* CID configuration to use in subsequent handshakes. */
1386
1387 /*! The next incoming CID, chosen by the user and applying to
1388 * all subsequent handshakes. This may be different from the
1389 * CID currently used in case the user has re-configured the CID
1390 * after an initial handshake. */
1391 unsigned char own_cid[ MBEDTLS_SSL_CID_IN_LEN_MAX ];
1392 uint8_t own_cid_len; /*!< The length of \c own_cid. */
1393 uint8_t negotiate_cid; /*!< This indicates whether the CID extension should
1394 * be negotiated in the next handshake or not.
1395 * Possible values are #MBEDTLS_SSL_CID_ENABLED
1396 * and #MBEDTLS_SSL_CID_DISABLED. */
1397 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1398 };
1399
1400 #if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
1401
1402 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
1403
1404 #define MBEDTLS_SSL_CHANNEL_OUTBOUND MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( 0 )
1405 #define MBEDTLS_SSL_CHANNEL_INBOUND MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( 1 )
1406
1407 #if defined(MBEDTLS_DEPRECATED_WARNING)
1408 #define MBEDTLS_DEPRECATED __attribute__((deprecated))
1409 #else
1410 #define MBEDTLS_DEPRECATED
1411 #endif /* MBEDTLS_DEPRECATED_WARNING */
1412
1413 MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_init)(
1414 mbedtls_ssl_context *ssl,
1415 const unsigned char *key_enc, const unsigned char *key_dec,
1416 size_t keylen,
1417 const unsigned char *iv_enc, const unsigned char *iv_dec,
1418 size_t ivlen,
1419 const unsigned char *mac_enc, const unsigned char *mac_dec,
1420 size_t maclen);
1421 MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_activate)(
1422 mbedtls_ssl_context *ssl,
1423 int direction );
1424 MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_reset)(
1425 mbedtls_ssl_context *ssl );
1426 MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_write)(
1427 mbedtls_ssl_context *ssl );
1428 MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_read)(
1429 mbedtls_ssl_context *ssl );
1430 MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_finish)(
1431 mbedtls_ssl_context *ssl );
1432
1433 #undef MBEDTLS_DEPRECATED
1434 #endif /* !MBEDTLS_DEPRECATED_REMOVED */
1435
1436 #endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
1437
1438 /**
1439 * \brief Return the name of the ciphersuite associated with the
1440 * given ID
1441 *
1442 * \param ciphersuite_id SSL ciphersuite ID
1443 *
1444 * \return a string containing the ciphersuite name
1445 */
1446 const char *mbedtls_ssl_get_ciphersuite_name( const int ciphersuite_id );
1447
1448 /**
1449 * \brief Return the ID of the ciphersuite associated with the
1450 * given name
1451 *
1452 * \param ciphersuite_name SSL ciphersuite name
1453 *
1454 * \return the ID with the ciphersuite or 0 if not found
1455 */
1456 int mbedtls_ssl_get_ciphersuite_id( const char *ciphersuite_name );
1457
1458 /**
1459 * \brief Initialize an SSL context
1460 * Just makes the context ready for mbedtls_ssl_setup() or
1461 * mbedtls_ssl_free()
1462 *
1463 * \param ssl SSL context
1464 */
1465 void mbedtls_ssl_init( mbedtls_ssl_context *ssl );
1466
1467 /**
1468 * \brief Set up an SSL context for use
1469 *
1470 * \note No copy of the configuration context is made, it can be
1471 * shared by many mbedtls_ssl_context structures.
1472 *
1473 * \warning The conf structure will be accessed during the session.
1474 * It must not be modified or freed as long as the session
1475 * is active.
1476 *
1477 * \warning This function must be called exactly once per context.
1478 * Calling mbedtls_ssl_setup again is not supported, even
1479 * if no session is active.
1480 *
1481 * \param ssl SSL context
1482 * \param conf SSL configuration to use
1483 *
1484 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED if
1485 * memory allocation failed
1486 */
1487 int mbedtls_ssl_setup( mbedtls_ssl_context *ssl,
1488 const mbedtls_ssl_config *conf );
1489
1490 /**
1491 * \brief Reset an already initialized SSL context for re-use
1492 * while retaining application-set variables, function
1493 * pointers and data.
1494 *
1495 * \param ssl SSL context
1496 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED,
1497 MBEDTLS_ERR_SSL_HW_ACCEL_FAILED or
1498 * MBEDTLS_ERR_SSL_COMPRESSION_FAILED
1499 */
1500 int mbedtls_ssl_session_reset( mbedtls_ssl_context *ssl );
1501
1502 /**
1503 * \brief Set the current endpoint type
1504 *
1505 * \param conf SSL configuration
1506 * \param endpoint must be MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
1507 */
1508 void mbedtls_ssl_conf_endpoint( mbedtls_ssl_config *conf, int endpoint );
1509
1510 /**
1511 * \brief Set the transport type (TLS or DTLS).
1512 * Default: TLS
1513 *
1514 * \note For DTLS, you must either provide a recv callback that
1515 * doesn't block, or one that handles timeouts, see
1516 * \c mbedtls_ssl_set_bio(). You also need to provide timer
1517 * callbacks with \c mbedtls_ssl_set_timer_cb().
1518 *
1519 * \param conf SSL configuration
1520 * \param transport transport type:
1521 * MBEDTLS_SSL_TRANSPORT_STREAM for TLS,
1522 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS.
1523 */
1524 void mbedtls_ssl_conf_transport( mbedtls_ssl_config *conf, int transport );
1525
1526 /**
1527 * \brief Set the certificate verification mode
1528 * Default: NONE on server, REQUIRED on client
1529 *
1530 * \param conf SSL configuration
1531 * \param authmode can be:
1532 *
1533 * MBEDTLS_SSL_VERIFY_NONE: peer certificate is not checked
1534 * (default on server)
1535 * (insecure on client)
1536 *
1537 * MBEDTLS_SSL_VERIFY_OPTIONAL: peer certificate is checked, however the
1538 * handshake continues even if verification failed;
1539 * mbedtls_ssl_get_verify_result() can be called after the
1540 * handshake is complete.
1541 *
1542 * MBEDTLS_SSL_VERIFY_REQUIRED: peer *must* present a valid certificate,
1543 * handshake is aborted if verification failed.
1544 * (default on client)
1545 *
1546 * \note On client, MBEDTLS_SSL_VERIFY_REQUIRED is the recommended mode.
1547 * With MBEDTLS_SSL_VERIFY_OPTIONAL, the user needs to call mbedtls_ssl_get_verify_result() at
1548 * the right time(s), which may not be obvious, while REQUIRED always perform
1549 * the verification as soon as possible. For example, REQUIRED was protecting
1550 * against the "triple handshake" attack even before it was found.
1551 */
1552 void mbedtls_ssl_conf_authmode( mbedtls_ssl_config *conf, int authmode );
1553
1554 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1555 /**
1556 * \brief Set the verification callback (Optional).
1557 *
1558 * If set, the provided verify callback is called for each
1559 * certificate in the peer's CRT chain, including the trusted
1560 * root. For more information, please see the documentation of
1561 * \c mbedtls_x509_crt_verify().
1562 *
1563 * \note For per context callbacks and contexts, please use
1564 * mbedtls_ssl_set_verify() instead.
1565 *
1566 * \param conf The SSL configuration to use.
1567 * \param f_vrfy The verification callback to use during CRT verification.
1568 * \param p_vrfy The opaque context to be passed to the callback.
1569 */
1570 void mbedtls_ssl_conf_verify( mbedtls_ssl_config *conf,
1571 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
1572 void *p_vrfy );
1573 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1574
1575 /**
1576 * \brief Set the random number generator callback
1577 *
1578 * \param conf SSL configuration
1579 * \param f_rng RNG function
1580 * \param p_rng RNG parameter
1581 */
1582 void mbedtls_ssl_conf_rng( mbedtls_ssl_config *conf,
1583 int (*f_rng)(void *, unsigned char *, size_t),
1584 void *p_rng );
1585
1586 /**
1587 * \brief Set the debug callback
1588 *
1589 * The callback has the following argument:
1590 * void * opaque context for the callback
1591 * int debug level
1592 * const char * file name
1593 * int line number
1594 * const char * message
1595 *
1596 * \param conf SSL configuration
1597 * \param f_dbg debug function
1598 * \param p_dbg debug parameter
1599 */
1600 void mbedtls_ssl_conf_dbg( mbedtls_ssl_config *conf,
1601 void (*f_dbg)(void *, int, const char *, int, const char *),
1602 void *p_dbg );
1603
1604 /**
1605 * \brief Set the underlying BIO callbacks for write, read and
1606 * read-with-timeout.
1607 *
1608 * \param ssl SSL context
1609 * \param p_bio parameter (context) shared by BIO callbacks
1610 * \param f_send write callback
1611 * \param f_recv read callback
1612 * \param f_recv_timeout blocking read callback with timeout.
1613 *
1614 * \note One of f_recv or f_recv_timeout can be NULL, in which case
1615 * the other is used. If both are non-NULL, f_recv_timeout is
1616 * used and f_recv is ignored (as if it were NULL).
1617 *
1618 * \note The two most common use cases are:
1619 * - non-blocking I/O, f_recv != NULL, f_recv_timeout == NULL
1620 * - blocking I/O, f_recv == NULL, f_recv_timout != NULL
1621 *
1622 * \note For DTLS, you need to provide either a non-NULL
1623 * f_recv_timeout callback, or a f_recv that doesn't block.
1624 *
1625 * \note See the documentations of \c mbedtls_ssl_send_t,
1626 * \c mbedtls_ssl_recv_t and \c mbedtls_ssl_recv_timeout_t for
1627 * the conventions those callbacks must follow.
1628 *
1629 * \note On some platforms, net_sockets.c provides
1630 * \c mbedtls_net_send(), \c mbedtls_net_recv() and
1631 * \c mbedtls_net_recv_timeout() that are suitable to be used
1632 * here.
1633 */
1634 void mbedtls_ssl_set_bio( mbedtls_ssl_context *ssl,
1635 void *p_bio,
1636 mbedtls_ssl_send_t *f_send,
1637 mbedtls_ssl_recv_t *f_recv,
1638 mbedtls_ssl_recv_timeout_t *f_recv_timeout );
1639
1640 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1641
1642 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1643
1644
1645 /**
1646 * \brief Configure the use of the Connection ID (CID)
1647 * extension in the next handshake.
1648 *
1649 * Reference: draft-ietf-tls-dtls-connection-id-05
1650 * https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05
1651 *
1652 * The DTLS CID extension allows the reliable association of
1653 * DTLS records to DTLS connections across changes in the
1654 * underlying transport (changed IP and Port metadata) by
1655 * adding explicit connection identifiers (CIDs) to the
1656 * headers of encrypted DTLS records. The desired CIDs are
1657 * configured by the application layer and are exchanged in
1658 * new `ClientHello` / `ServerHello` extensions during the
1659 * handshake, where each side indicates the CID it wants the
1660 * peer to use when writing encrypted messages. The CIDs are
1661 * put to use once records get encrypted: the stack discards
1662 * any incoming records that don't include the configured CID
1663 * in their header, and adds the peer's requested CID to the
1664 * headers of outgoing messages.
1665 *
1666 * This API enables or disables the use of the CID extension
1667 * in the next handshake and sets the value of the CID to
1668 * be used for incoming messages.
1669 *
1670 * \param ssl The SSL context to configure. This must be initialized.
1671 * \param enable This value determines whether the CID extension should
1672 * be used or not. Possible values are:
1673 * - MBEDTLS_SSL_CID_ENABLED to enable the use of the CID.
1674 * - MBEDTLS_SSL_CID_DISABLED (default) to disable the use
1675 * of the CID.
1676 * \param own_cid The address of the readable buffer holding the CID we want
1677 * the peer to use when sending encrypted messages to us.
1678 * This may be \c NULL if \p own_cid_len is \c 0.
1679 * This parameter is unused if \p enabled is set to
1680 * MBEDTLS_SSL_CID_DISABLED.
1681 * \param own_cid_len The length of \p own_cid.
1682 * This parameter is unused if \p enabled is set to
1683 * MBEDTLS_SSL_CID_DISABLED.
1684 *
1685 * \note The value of \p own_cid_len must match the value of the
1686 * \c len parameter passed to mbedtls_ssl_conf_cid()
1687 * when configuring the ::mbedtls_ssl_config that \p ssl
1688 * is bound to.
1689 *
1690 * \note This CID configuration applies to subsequent handshakes
1691 * performed on the SSL context \p ssl, but does not trigger
1692 * one. You still have to call `mbedtls_ssl_handshake()`
1693 * (for the initial handshake) or `mbedtls_ssl_renegotiate()`
1694 * (for a renegotiation handshake) explicitly after a
1695 * successful call to this function to run the handshake.
1696 *
1697 * \note This call cannot guarantee that the use of the CID
1698 * will be successfully negotiated in the next handshake,
1699 * because the peer might not support it. Specifically:
1700 * - On the Client, enabling the use of the CID through
1701 * this call implies that the `ClientHello` in the next
1702 * handshake will include the CID extension, thereby
1703 * offering the use of the CID to the server. Only if
1704 * the `ServerHello` contains the CID extension, too,
1705 * the CID extension will actually be put to use.
1706 * - On the Server, enabling the use of the CID through
1707 * this call implies that that the server will look for
1708 * the CID extension in a `ClientHello` from the client,
1709 * and, if present, reply with a CID extension in its
1710 * `ServerHello`.
1711 *
1712 * \note To check whether the use of the CID was negotiated
1713 * after the subsequent handshake has completed, please
1714 * use the API mbedtls_ssl_get_peer_cid().
1715 *
1716 * \warning If the use of the CID extension is enabled in this call
1717 * and the subsequent handshake negotiates its use, Mbed TLS
1718 * will silently drop every packet whose CID does not match
1719 * the CID configured in \p own_cid. It is the responsibility
1720 * of the user to adapt the underlying transport to take care
1721 * of CID-based demultiplexing before handing datagrams to
1722 * Mbed TLS.
1723 *
1724 * \return \c 0 on success. In this case, the CID configuration
1725 * applies to the next handshake.
1726 * \return A negative error code on failure.
1727 */
1728 int mbedtls_ssl_set_cid( mbedtls_ssl_context *ssl,
1729 int enable,
1730 unsigned char const *own_cid,
1731 size_t own_cid_len );
1732
1733 /**
1734 * \brief Get information about the use of the CID extension
1735 * in the current connection.
1736 *
1737 * \param ssl The SSL context to query.
1738 * \param enabled The address at which to store whether the CID extension
1739 * is currently in use or not. If the CID is in use,
1740 * `*enabled` is set to MBEDTLS_SSL_CID_ENABLED;
1741 * otherwise, it is set to MBEDTLS_SSL_CID_DISABLED.
1742 * \param peer_cid The address of the buffer in which to store the CID
1743 * chosen by the peer (if the CID extension is used).
1744 * This may be \c NULL in case the value of peer CID
1745 * isn't needed. If it is not \c NULL, \p peer_cid_len
1746 * must not be \c NULL.
1747 * \param peer_cid_len The address at which to store the size of the CID
1748 * chosen by the peer (if the CID extension is used).
1749 * This is also the number of Bytes in \p peer_cid that
1750 * have been written.
1751 * This may be \c NULL in case the length of the peer CID
1752 * isn't needed. If it is \c NULL, \p peer_cid must be
1753 * \c NULL, too.
1754 *
1755 * \note This applies to the state of the CID negotiated in
1756 * the last complete handshake. If a handshake is in
1757 * progress, this function will attempt to complete
1758 * the handshake first.
1759 *
1760 * \note If CID extensions have been exchanged but both client
1761 * and server chose to use an empty CID, this function
1762 * sets `*enabled` to #MBEDTLS_SSL_CID_DISABLED
1763 * (the rationale for this is that the resulting
1764 * communication is the same as if the CID extensions
1765 * hadn't been used).
1766 *
1767 * \return \c 0 on success.
1768 * \return A negative error code on failure.
1769 */
1770 int mbedtls_ssl_get_peer_cid( mbedtls_ssl_context *ssl,
1771 int *enabled,
1772 unsigned char peer_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ],
1773 size_t *peer_cid_len );
1774
1775 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1776
1777 /**
1778 * \brief Set the Maximum Tranport Unit (MTU).
1779 * Special value: 0 means unset (no limit).
1780 * This represents the maximum size of a datagram payload
1781 * handled by the transport layer (usually UDP) as determined
1782 * by the network link and stack. In practice, this controls
1783 * the maximum size datagram the DTLS layer will pass to the
1784 * \c f_send() callback set using \c mbedtls_ssl_set_bio().
1785 *
1786 * \note The limit on datagram size is converted to a limit on
1787 * record payload by subtracting the current overhead of
1788 * encapsulation and encryption/authentication if any.
1789 *
1790 * \note This can be called at any point during the connection, for
1791 * example when a Path Maximum Transfer Unit (PMTU)
1792 * estimate becomes available from other sources,
1793 * such as lower (or higher) protocol layers.
1794 *
1795 * \note This setting only controls the size of the packets we send,
1796 * and does not restrict the size of the datagrams we're
1797 * willing to receive. Client-side, you can request the
1798 * server to use smaller records with \c
1799 * mbedtls_ssl_conf_max_frag_len().
1800 *
1801 * \note If both a MTU and a maximum fragment length have been
1802 * configured (or negotiated with the peer), the resulting
1803 * lower limit on record payload (see first note) is used.
1804 *
1805 * \note This can only be used to decrease the maximum size
1806 * of datagrams (hence records, see first note) sent. It
1807 * cannot be used to increase the maximum size of records over
1808 * the limit set by #MBEDTLS_SSL_OUT_CONTENT_LEN.
1809 *
1810 * \note Values lower than the current record layer expansion will
1811 * result in an error when trying to send data.
1812 *
1813 * \note Using record compression together with a non-zero MTU value
1814 * will result in an error when trying to send data.
1815 *
1816 * \param ssl SSL context
1817 * \param mtu Value of the path MTU in bytes
1818 */
1819 void mbedtls_ssl_set_mtu( mbedtls_ssl_context *ssl, uint16_t mtu );
1820 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1821
1822 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1823 /**
1824 * \brief Set a connection-specific verification callback (optional).
1825 *
1826 * If set, the provided verify callback is called for each
1827 * certificate in the peer's CRT chain, including the trusted
1828 * root. For more information, please see the documentation of
1829 * \c mbedtls_x509_crt_verify().
1830 *
1831 * \note This call is analogous to mbedtls_ssl_conf_verify() but
1832 * binds the verification callback and context to an SSL context
1833 * as opposed to an SSL configuration.
1834 * If mbedtls_ssl_conf_verify() and mbedtls_ssl_set_verify()
1835 * are both used, mbedtls_ssl_set_verify() takes precedence.
1836 *
1837 * \param ssl The SSL context to use.
1838 * \param f_vrfy The verification callback to use during CRT verification.
1839 * \param p_vrfy The opaque context to be passed to the callback.
1840 */
1841 void mbedtls_ssl_set_verify( mbedtls_ssl_context *ssl,
1842 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
1843 void *p_vrfy );
1844 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1845
1846 /**
1847 * \brief Set the timeout period for mbedtls_ssl_read()
1848 * (Default: no timeout.)
1849 *
1850 * \param conf SSL configuration context
1851 * \param timeout Timeout value in milliseconds.
1852 * Use 0 for no timeout (default).
1853 *
1854 * \note With blocking I/O, this will only work if a non-NULL
1855 * \c f_recv_timeout was set with \c mbedtls_ssl_set_bio().
1856 * With non-blocking I/O, this will only work if timer
1857 * callbacks were set with \c mbedtls_ssl_set_timer_cb().
1858 *
1859 * \note With non-blocking I/O, you may also skip this function
1860 * altogether and handle timeouts at the application layer.
1861 */
1862 void mbedtls_ssl_conf_read_timeout( mbedtls_ssl_config *conf, uint32_t timeout );
1863
1864 #if defined(MBEDTLS_SSL_RECORD_CHECKING)
1865 /**
1866 * \brief Check whether a buffer contains a valid and authentic record
1867 * that has not been seen before. (DTLS only).
1868 *
1869 * This function does not change the user-visible state
1870 * of the SSL context. Its sole purpose is to provide
1871 * an indication of the legitimacy of an incoming record.
1872 *
1873 * This can be useful e.g. in distributed server environments
1874 * using the DTLS Connection ID feature, in which connections
1875 * might need to be passed between service instances on a change
1876 * of peer address, but where such disruptive operations should
1877 * only happen after the validity of incoming records has been
1878 * confirmed.
1879 *
1880 * \param ssl The SSL context to use.
1881 * \param buf The address of the buffer holding the record to be checked.
1882 * This must be a read/write buffer of length \p buflen Bytes.
1883 * \param buflen The length of \p buf in Bytes.
1884 *
1885 * \note This routine only checks whether the provided buffer begins
1886 * with a valid and authentic record that has not been seen
1887 * before, but does not check potential data following the
1888 * initial record. In particular, it is possible to pass DTLS
1889 * datagrams containing multiple records, in which case only
1890 * the first record is checked.
1891 *
1892 * \note This function modifies the input buffer \p buf. If you need
1893 * to preserve the original record, you have to maintain a copy.
1894 *
1895 * \return \c 0 if the record is valid and authentic and has not been
1896 * seen before.
1897 * \return MBEDTLS_ERR_SSL_INVALID_MAC if the check completed
1898 * successfully but the record was found to be not authentic.
1899 * \return MBEDTLS_ERR_SSL_INVALID_RECORD if the check completed
1900 * successfully but the record was found to be invalid for
1901 * a reason different from authenticity checking.
1902 * \return MBEDTLS_ERR_SSL_UNEXPECTED_RECORD if the check completed
1903 * successfully but the record was found to be unexpected
1904 * in the state of the SSL context, including replayed records.
1905 * \return Another negative error code on different kinds of failure.
1906 * In this case, the SSL context becomes unusable and needs
1907 * to be freed or reset before reuse.
1908 */
1909 int mbedtls_ssl_check_record( mbedtls_ssl_context const *ssl,
1910 unsigned char *buf,
1911 size_t buflen );
1912 #endif /* MBEDTLS_SSL_RECORD_CHECKING */
1913
1914 /**
1915 * \brief Set the timer callbacks (Mandatory for DTLS.)
1916 *
1917 * \param ssl SSL context
1918 * \param p_timer parameter (context) shared by timer callbacks
1919 * \param f_set_timer set timer callback
1920 * \param f_get_timer get timer callback. Must return:
1921 *
1922 * \note See the documentation of \c mbedtls_ssl_set_timer_t and
1923 * \c mbedtls_ssl_get_timer_t for the conventions this pair of
1924 * callbacks must follow.
1925 *
1926 * \note On some platforms, timing.c provides
1927 * \c mbedtls_timing_set_delay() and
1928 * \c mbedtls_timing_get_delay() that are suitable for using
1929 * here, except if using an event-driven style.
1930 *
1931 * \note See also the "DTLS tutorial" article in our knowledge base.
1932 * https://tls.mbed.org/kb/how-to/dtls-tutorial
1933 */
1934 void mbedtls_ssl_set_timer_cb( mbedtls_ssl_context *ssl,
1935 void *p_timer,
1936 mbedtls_ssl_set_timer_t *f_set_timer,
1937 mbedtls_ssl_get_timer_t *f_get_timer );
1938
1939 /**
1940 * \brief Callback type: generate and write session ticket
1941 *
1942 * \note This describes what a callback implementation should do.
1943 * This callback should generate an encrypted and
1944 * authenticated ticket for the session and write it to the
1945 * output buffer. Here, ticket means the opaque ticket part
1946 * of the NewSessionTicket structure of RFC 5077.
1947 *
1948 * \param p_ticket Context for the callback
1949 * \param session SSL session to be written in the ticket
1950 * \param start Start of the output buffer
1951 * \param end End of the output buffer
1952 * \param tlen On exit, holds the length written
1953 * \param lifetime On exit, holds the lifetime of the ticket in seconds
1954 *
1955 * \return 0 if successful, or
1956 * a specific MBEDTLS_ERR_XXX code.
1957 */
1958 typedef int mbedtls_ssl_ticket_write_t( void *p_ticket,
1959 const mbedtls_ssl_session *session,
1960 unsigned char *start,
1961 const unsigned char *end,
1962 size_t *tlen,
1963 uint32_t *lifetime );
1964
1965 #if defined(MBEDTLS_SSL_EXPORT_KEYS)
1966 /**
1967 * \brief Callback type: Export key block and master secret
1968 *
1969 * \note This is required for certain uses of TLS, e.g. EAP-TLS
1970 * (RFC 5216) and Thread. The key pointers are ephemeral and
1971 * therefore must not be stored. The master secret and keys
1972 * should not be used directly except as an input to a key
1973 * derivation function.
1974 *
1975 * \param p_expkey Context for the callback
1976 * \param ms Pointer to master secret (fixed length: 48 bytes)
1977 * \param kb Pointer to key block, see RFC 5246 section 6.3
1978 * (variable length: 2 * maclen + 2 * keylen + 2 * ivlen).
1979 * \param maclen MAC length
1980 * \param keylen Key length
1981 * \param ivlen IV length
1982 *
1983 * \return 0 if successful, or
1984 * a specific MBEDTLS_ERR_XXX code.
1985 */
1986 typedef int mbedtls_ssl_export_keys_t( void *p_expkey,
1987 const unsigned char *ms,
1988 const unsigned char *kb,
1989 size_t maclen,
1990 size_t keylen,
1991 size_t ivlen );
1992
1993 /**
1994 * \brief Callback type: Export key block, master secret,
1995 * handshake randbytes and the tls_prf function
1996 * used to derive keys.
1997 *
1998 * \note This is required for certain uses of TLS, e.g. EAP-TLS
1999 * (RFC 5216) and Thread. The key pointers are ephemeral and
2000 * therefore must not be stored. The master secret and keys
2001 * should not be used directly except as an input to a key
2002 * derivation function.
2003 *
2004 * \param p_expkey Context for the callback.
2005 * \param ms Pointer to master secret (fixed length: 48 bytes).
2006 * \param kb Pointer to key block, see RFC 5246 section 6.3.
2007 * (variable length: 2 * maclen + 2 * keylen + 2 * ivlen).
2008 * \param maclen MAC length.
2009 * \param keylen Key length.
2010 * \param ivlen IV length.
2011 * \param client_random The client random bytes.
2012 * \param server_random The server random bytes.
2013 * \param tls_prf_type The tls_prf enum type.
2014 *
2015 * \return 0 if successful, or
2016 * a specific MBEDTLS_ERR_XXX code.
2017 */
2018 typedef int mbedtls_ssl_export_keys_ext_t( void *p_expkey,
2019 const unsigned char *ms,
2020 const unsigned char *kb,
2021 size_t maclen,
2022 size_t keylen,
2023 size_t ivlen,
2024 const unsigned char client_random[32],
2025 const unsigned char server_random[32],
2026 mbedtls_tls_prf_types tls_prf_type );
2027 #endif /* MBEDTLS_SSL_EXPORT_KEYS */
2028
2029 /**
2030 * \brief Callback type: parse and load session ticket
2031 *
2032 * \note This describes what a callback implementation should do.
2033 * This callback should parse a session ticket as generated
2034 * by the corresponding mbedtls_ssl_ticket_write_t function,
2035 * and, if the ticket is authentic and valid, load the
2036 * session.
2037 *
2038 * \note The implementation is allowed to modify the first len
2039 * bytes of the input buffer, eg to use it as a temporary
2040 * area for the decrypted ticket contents.
2041 *
2042 * \param p_ticket Context for the callback
2043 * \param session SSL session to be loaded
2044 * \param buf Start of the buffer containing the ticket
2045 * \param len Length of the ticket.
2046 *
2047 * \return 0 if successful, or
2048 * MBEDTLS_ERR_SSL_INVALID_MAC if not authentic, or
2049 * MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED if expired, or
2050 * any other non-zero code for other failures.
2051 */
2052 typedef int mbedtls_ssl_ticket_parse_t( void *p_ticket,
2053 mbedtls_ssl_session *session,
2054 unsigned char *buf,
2055 size_t len );
2056
2057 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
2058 /**
2059 * \brief Configure SSL session ticket callbacks (server only).
2060 * (Default: none.)
2061 *
2062 * \note On server, session tickets are enabled by providing
2063 * non-NULL callbacks.
2064 *
2065 * \note On client, use \c mbedtls_ssl_conf_session_tickets().
2066 *
2067 * \param conf SSL configuration context
2068 * \param f_ticket_write Callback for writing a ticket
2069 * \param f_ticket_parse Callback for parsing a ticket
2070 * \param p_ticket Context shared by the two callbacks
2071 */
2072 void mbedtls_ssl_conf_session_tickets_cb( mbedtls_ssl_config *conf,
2073 mbedtls_ssl_ticket_write_t *f_ticket_write,
2074 mbedtls_ssl_ticket_parse_t *f_ticket_parse,
2075 void *p_ticket );
2076 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
2077
2078 #if defined(MBEDTLS_SSL_EXPORT_KEYS)
2079 /**
2080 * \brief Configure key export callback.
2081 * (Default: none.)
2082 *
2083 * \note See \c mbedtls_ssl_export_keys_t.
2084 *
2085 * \param conf SSL configuration context
2086 * \param f_export_keys Callback for exporting keys
2087 * \param p_export_keys Context for the callback
2088 */
2089 void mbedtls_ssl_conf_export_keys_cb( mbedtls_ssl_config *conf,
2090 mbedtls_ssl_export_keys_t *f_export_keys,
2091 void *p_export_keys );
2092
2093 /**
2094 * \brief Configure extended key export callback.
2095 * (Default: none.)
2096 *
2097 * \note See \c mbedtls_ssl_export_keys_ext_t.
2098 * \warning Exported key material must not be used for any purpose
2099 * before the (D)TLS handshake is completed
2100 *
2101 * \param conf SSL configuration context
2102 * \param f_export_keys_ext Callback for exporting keys
2103 * \param p_export_keys Context for the callback
2104 */
2105 void mbedtls_ssl_conf_export_keys_ext_cb( mbedtls_ssl_config *conf,
2106 mbedtls_ssl_export_keys_ext_t *f_export_keys_ext,
2107 void *p_export_keys );
2108 #endif /* MBEDTLS_SSL_EXPORT_KEYS */
2109
2110 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
2111 /**
2112 * \brief Configure asynchronous private key operation callbacks.
2113 *
2114 * \param conf SSL configuration context
2115 * \param f_async_sign Callback to start a signature operation. See
2116 * the description of ::mbedtls_ssl_async_sign_t
2117 * for more information. This may be \c NULL if the
2118 * external processor does not support any signature
2119 * operation; in this case the private key object
2120 * associated with the certificate will be used.
2121 * \param f_async_decrypt Callback to start a decryption operation. See
2122 * the description of ::mbedtls_ssl_async_decrypt_t
2123 * for more information. This may be \c NULL if the
2124 * external processor does not support any decryption
2125 * operation; in this case the private key object
2126 * associated with the certificate will be used.
2127 * \param f_async_resume Callback to resume an asynchronous operation. See
2128 * the description of ::mbedtls_ssl_async_resume_t
2129 * for more information. This may not be \c NULL unless
2130 * \p f_async_sign and \p f_async_decrypt are both
2131 * \c NULL.
2132 * \param f_async_cancel Callback to cancel an asynchronous operation. See
2133 * the description of ::mbedtls_ssl_async_cancel_t
2134 * for more information. This may be \c NULL if
2135 * no cleanup is needed.
2136 * \param config_data A pointer to configuration data which can be
2137 * retrieved with
2138 * mbedtls_ssl_conf_get_async_config_data(). The
2139 * library stores this value without dereferencing it.
2140 */
2141 void mbedtls_ssl_conf_async_private_cb( mbedtls_ssl_config *conf,
2142 mbedtls_ssl_async_sign_t *f_async_sign,
2143 mbedtls_ssl_async_decrypt_t *f_async_decrypt,
2144 mbedtls_ssl_async_resume_t *f_async_resume,
2145 mbedtls_ssl_async_cancel_t *f_async_cancel,
2146 void *config_data );
2147
2148 /**
2149 * \brief Retrieve the configuration data set by
2150 * mbedtls_ssl_conf_async_private_cb().
2151 *
2152 * \param conf SSL configuration context
2153 * \return The configuration data set by
2154 * mbedtls_ssl_conf_async_private_cb().
2155 */
2156 void *mbedtls_ssl_conf_get_async_config_data( const mbedtls_ssl_config *conf );
2157
2158 /**
2159 * \brief Retrieve the asynchronous operation user context.
2160 *
2161 * \note This function may only be called while a handshake
2162 * is in progress.
2163 *
2164 * \param ssl The SSL context to access.
2165 *
2166 * \return The asynchronous operation user context that was last
2167 * set during the current handshake. If
2168 * mbedtls_ssl_set_async_operation_data() has not yet been
2169 * called during the current handshake, this function returns
2170 * \c NULL.
2171 */
2172 void *mbedtls_ssl_get_async_operation_data( const mbedtls_ssl_context *ssl );
2173
2174 /**
2175 * \brief Retrieve the asynchronous operation user context.
2176 *
2177 * \note This function may only be called while a handshake
2178 * is in progress.
2179 *
2180 * \param ssl The SSL context to access.
2181 * \param ctx The new value of the asynchronous operation user context.
2182 * Call mbedtls_ssl_get_async_operation_data() later during the
2183 * same handshake to retrieve this value.
2184 */
2185 void mbedtls_ssl_set_async_operation_data( mbedtls_ssl_context *ssl,
2186 void *ctx );
2187 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
2188
2189 /**
2190 * \brief Callback type: generate a cookie
2191 *
2192 * \param ctx Context for the callback
2193 * \param p Buffer to write to,
2194 * must be updated to point right after the cookie
2195 * \param end Pointer to one past the end of the output buffer
2196 * \param info Client ID info that was passed to
2197 * \c mbedtls_ssl_set_client_transport_id()
2198 * \param ilen Length of info in bytes
2199 *
2200 * \return The callback must return 0 on success,
2201 * or a negative error code.
2202 */
2203 typedef int mbedtls_ssl_cookie_write_t( void *ctx,
2204 unsigned char **p, unsigned char *end,
2205 const unsigned char *info, size_t ilen );
2206
2207 /**
2208 * \brief Callback type: verify a cookie
2209 *
2210 * \param ctx Context for the callback
2211 * \param cookie Cookie to verify
2212 * \param clen Length of cookie
2213 * \param info Client ID info that was passed to
2214 * \c mbedtls_ssl_set_client_transport_id()
2215 * \param ilen Length of info in bytes
2216 *
2217 * \return The callback must return 0 if cookie is valid,
2218 * or a negative error code.
2219 */
2220 typedef int mbedtls_ssl_cookie_check_t( void *ctx,
2221 const unsigned char *cookie, size_t clen,
2222 const unsigned char *info, size_t ilen );
2223
2224 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
2225 /**
2226 * \brief Register callbacks for DTLS cookies
2227 * (Server only. DTLS only.)
2228 *
2229 * Default: dummy callbacks that fail, in order to force you to
2230 * register working callbacks (and initialize their context).
2231 *
2232 * To disable HelloVerifyRequest, register NULL callbacks.
2233 *
2234 * \warning Disabling hello verification allows your server to be used
2235 * for amplification in DoS attacks against other hosts.
2236 * Only disable if you known this can't happen in your
2237 * particular environment.
2238 *
2239 * \note See comments on \c mbedtls_ssl_handshake() about handling
2240 * the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected
2241 * on the first handshake attempt when this is enabled.
2242 *
2243 * \note This is also necessary to handle client reconnection from
2244 * the same port as described in RFC 6347 section 4.2.8 (only
2245 * the variant with cookies is supported currently). See
2246 * comments on \c mbedtls_ssl_read() for details.
2247 *
2248 * \param conf SSL configuration
2249 * \param f_cookie_write Cookie write callback
2250 * \param f_cookie_check Cookie check callback
2251 * \param p_cookie Context for both callbacks
2252 */
2253 void mbedtls_ssl_conf_dtls_cookies( mbedtls_ssl_config *conf,
2254 mbedtls_ssl_cookie_write_t *f_cookie_write,
2255 mbedtls_ssl_cookie_check_t *f_cookie_check,
2256 void *p_cookie );
2257
2258 /**
2259 * \brief Set client's transport-level identification info.
2260 * (Server only. DTLS only.)
2261 *
2262 * This is usually the IP address (and port), but could be
2263 * anything identify the client depending on the underlying
2264 * network stack. Used for HelloVerifyRequest with DTLS.
2265 * This is *not* used to route the actual packets.
2266 *
2267 * \param ssl SSL context
2268 * \param info Transport-level info identifying the client (eg IP + port)
2269 * \param ilen Length of info in bytes
2270 *
2271 * \note An internal copy is made, so the info buffer can be reused.
2272 *
2273 * \return 0 on success,
2274 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client,
2275 * MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory.
2276 */
2277 int mbedtls_ssl_set_client_transport_id( mbedtls_ssl_context *ssl,
2278 const unsigned char *info,
2279 size_t ilen );
2280
2281 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
2282
2283 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
2284 /**
2285 * \brief Enable or disable anti-replay protection for DTLS.
2286 * (DTLS only, no effect on TLS.)
2287 * Default: enabled.
2288 *
2289 * \param conf SSL configuration
2290 * \param mode MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED.
2291 *
2292 * \warning Disabling this is a security risk unless the application
2293 * protocol handles duplicated packets in a safe way. You
2294 * should not disable this without careful consideration.
2295 * However, if your application already detects duplicated
2296 * packets and needs information about them to adjust its
2297 * transmission strategy, then you'll want to disable this.
2298 */
2299 void mbedtls_ssl_conf_dtls_anti_replay( mbedtls_ssl_config *conf, char mode );
2300 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
2301
2302 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
2303 /**
2304 * \brief Set a limit on the number of records with a bad MAC
2305 * before terminating the connection.
2306 * (DTLS only, no effect on TLS.)
2307 * Default: 0 (disabled).
2308 *
2309 * \param conf SSL configuration
2310 * \param limit Limit, or 0 to disable.
2311 *
2312 * \note If the limit is N, then the connection is terminated when
2313 * the Nth non-authentic record is seen.
2314 *
2315 * \note Records with an invalid header are not counted, only the
2316 * ones going through the authentication-decryption phase.
2317 *
2318 * \note This is a security trade-off related to the fact that it's
2319 * often relatively easy for an active attacker ot inject UDP
2320 * datagrams. On one hand, setting a low limit here makes it
2321 * easier for such an attacker to forcibly terminated a
2322 * connection. On the other hand, a high limit or no limit
2323 * might make us waste resources checking authentication on
2324 * many bogus packets.
2325 */
2326 void mbedtls_ssl_conf_dtls_badmac_limit( mbedtls_ssl_config *conf, unsigned limit );
2327 #endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */
2328
2329 #if defined(MBEDTLS_SSL_PROTO_DTLS)
2330
2331 /**
2332 * \brief Allow or disallow packing of multiple handshake records
2333 * within a single datagram.
2334 *
2335 * \param ssl The SSL context to configure.
2336 * \param allow_packing This determines whether datagram packing may
2337 * be used or not. A value of \c 0 means that every
2338 * record will be sent in a separate datagram; a
2339 * value of \c 1 means that, if space permits,
2340 * multiple handshake messages (including CCS) belonging to
2341 * a single flight may be packed within a single datagram.
2342 *
2343 * \note This is enabled by default and should only be disabled
2344 * for test purposes, or if datagram packing causes
2345 * interoperability issues with peers that don't support it.
2346 *
2347 * \note Allowing datagram packing reduces the network load since
2348 * there's less overhead if multiple messages share the same
2349 * datagram. Also, it increases the handshake efficiency
2350 * since messages belonging to a single datagram will not
2351 * be reordered in transit, and so future message buffering
2352 * or flight retransmission (if no buffering is used) as
2353 * means to deal with reordering are needed less frequently.
2354 *
2355 * \note Application records are not affected by this option and
2356 * are currently always sent in separate datagrams.
2357 *
2358 */
2359 void mbedtls_ssl_set_datagram_packing( mbedtls_ssl_context *ssl,
2360 unsigned allow_packing );
2361
2362 /**
2363 * \brief Set retransmit timeout values for the DTLS handshake.
2364 * (DTLS only, no effect on TLS.)
2365 *
2366 * \param conf SSL configuration
2367 * \param min Initial timeout value in milliseconds.
2368 * Default: 1000 (1 second).
2369 * \param max Maximum timeout value in milliseconds.
2370 * Default: 60000 (60 seconds).
2371 *
2372 * \note Default values are from RFC 6347 section 4.2.4.1.
2373 *
2374 * \note The 'min' value should typically be slightly above the
2375 * expected round-trip time to your peer, plus whatever time
2376 * it takes for the peer to process the message. For example,
2377 * if your RTT is about 600ms and you peer needs up to 1s to
2378 * do the cryptographic operations in the handshake, then you
2379 * should set 'min' slightly above 1600. Lower values of 'min'
2380 * might cause spurious resends which waste network resources,
2381 * while larger value of 'min' will increase overall latency
2382 * on unreliable network links.
2383 *
2384 * \note The more unreliable your network connection is, the larger
2385 * your max / min ratio needs to be in order to achieve
2386 * reliable handshakes.
2387 *
2388 * \note Messages are retransmitted up to log2(ceil(max/min)) times.
2389 * For example, if min = 1s and max = 5s, the retransmit plan
2390 * goes: send ... 1s -> resend ... 2s -> resend ... 4s ->
2391 * resend ... 5s -> give up and return a timeout error.
2392 */
2393 void mbedtls_ssl_conf_handshake_timeout( mbedtls_ssl_config *conf, uint32_t min, uint32_t max );
2394 #endif /* MBEDTLS_SSL_PROTO_DTLS */
2395
2396 #if defined(MBEDTLS_SSL_SRV_C)
2397 /**
2398 * \brief Set the session cache callbacks (server-side only)
2399 * If not set, no session resuming is done (except if session
2400 * tickets are enabled too).
2401 *
2402 * The session cache has the responsibility to check for stale
2403 * entries based on timeout. See RFC 5246 for recommendations.
2404 *
2405 * Warning: session.peer_cert is cleared by the SSL/TLS layer on
2406 * connection shutdown, so do not cache the pointer! Either set
2407 * it to NULL or make a full copy of the certificate.
2408 *
2409 * The get callback is called once during the initial handshake
2410 * to enable session resuming. The get function has the
2411 * following parameters: (void *parameter, mbedtls_ssl_session *session)
2412 * If a valid entry is found, it should fill the master of
2413 * the session object with the cached values and return 0,
2414 * return 1 otherwise. Optionally peer_cert can be set as well
2415 * if it is properly present in cache entry.
2416 *
2417 * The set callback is called once during the initial handshake
2418 * to enable session resuming after the entire handshake has
2419 * been finished. The set function has the following parameters:
2420 * (void *parameter, const mbedtls_ssl_session *session). The function
2421 * should create a cache entry for future retrieval based on
2422 * the data in the session structure and should keep in mind
2423 * that the mbedtls_ssl_session object presented (and all its referenced
2424 * data) is cleared by the SSL/TLS layer when the connection is
2425 * terminated. It is recommended to add metadata to determine if
2426 * an entry is still valid in the future. Return 0 if
2427 * successfully cached, return 1 otherwise.
2428 *
2429 * \param conf SSL configuration
2430 * \param p_cache parmater (context) for both callbacks
2431 * \param f_get_cache session get callback
2432 * \param f_set_cache session set callback
2433 */
2434 void mbedtls_ssl_conf_session_cache( mbedtls_ssl_config *conf,
2435 void *p_cache,
2436 int (*f_get_cache)(void *, mbedtls_ssl_session *),
2437 int (*f_set_cache)(void *, const mbedtls_ssl_session *) );
2438 #endif /* MBEDTLS_SSL_SRV_C */
2439
2440 #if defined(MBEDTLS_SSL_CLI_C)
2441 /**
2442 * \brief Request resumption of session (client-side only)
2443 * Session data is copied from presented session structure.
2444 *
2445 * \param ssl SSL context
2446 * \param session session context
2447 *
2448 * \return 0 if successful,
2449 * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed,
2450 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or
2451 * arguments are otherwise invalid
2452 *
2453 * \sa mbedtls_ssl_get_session()
2454 */
2455 int mbedtls_ssl_set_session( mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session );
2456 #endif /* MBEDTLS_SSL_CLI_C */
2457
2458 /**
2459 * \brief Load serialized session data into a session structure.
2460 * On client, this can be used for loading saved sessions
2461 * before resuming them with mbedstls_ssl_set_session().
2462 * On server, this can be used for alternative implementations
2463 * of session cache or session tickets.
2464 *
2465 * \warning If a peer certificate chain is associated with the session,
2466 * the serialized state will only contain the peer's
2467 * end-entity certificate and the result of the chain
2468 * verification (unless verification was disabled), but not
2469 * the rest of the chain.
2470 *
2471 * \see mbedtls_ssl_session_save()
2472 * \see mbedtls_ssl_set_session()
2473 *
2474 * \param session The session structure to be populated. It must have been
2475 * initialised with mbedtls_ssl_session_init() but not
2476 * populated yet.
2477 * \param buf The buffer holding the serialized session data. It must be a
2478 * readable buffer of at least \p len bytes.
2479 * \param len The size of the serialized data in bytes.
2480 *
2481 * \return \c 0 if successful.
2482 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
2483 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
2484 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
2485 * was generated in a different version or configuration of
2486 * Mbed TLS.
2487 * \return Another negative value for other kinds of errors (for
2488 * example, unsupported features in the embedded certificate).
2489 */
2490 int mbedtls_ssl_session_load( mbedtls_ssl_session *session,
2491 const unsigned char *buf,
2492 size_t len );
2493
2494 /**
2495 * \brief Save session structure as serialized data in a buffer.
2496 * On client, this can be used for saving session data,
2497 * potentially in non-volatile storage, for resuming later.
2498 * On server, this can be used for alternative implementations
2499 * of session cache or session tickets.
2500 *
2501 * \see mbedtls_ssl_session_load()
2502 * \see mbedtls_ssl_get_session_pointer()
2503 *
2504 * \param session The session structure to be saved.
2505 * \param buf The buffer to write the serialized data to. It must be a
2506 * writeable buffer of at least \p len bytes, or may be \c
2507 * NULL if \p len is \c 0.
2508 * \param buf_len The number of bytes available for writing in \p buf.
2509 * \param olen The size in bytes of the data that has been or would have
2510 * been written. It must point to a valid \c size_t.
2511 *
2512 * \note \p olen is updated to the correct value regardless of
2513 * whether \p buf_len was large enough. This makes it possible
2514 * to determine the necessary size by calling this function
2515 * with \p buf set to \c NULL and \p buf_len to \c 0.
2516 *
2517 * \return \c 0 if successful.
2518 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
2519 */
2520 int mbedtls_ssl_session_save( const mbedtls_ssl_session *session,
2521 unsigned char *buf,
2522 size_t buf_len,
2523 size_t *olen );
2524
2525 /**
2526 * \brief Get a pointer to the current session structure, for example
2527 * to serialize it.
2528 *
2529 * \warning Ownership of the session remains with the SSL context, and
2530 * the returned pointer is only guaranteed to be valid until
2531 * the next API call operating on the same \p ssl context.
2532 *
2533 * \see mbedtls_ssl_session_save()
2534 *
2535 * \param ssl The SSL context.
2536 *
2537 * \return A pointer to the current session if successful.
2538 * \return \c NULL if no session is active.
2539 */
2540 const mbedtls_ssl_session *mbedtls_ssl_get_session_pointer( const mbedtls_ssl_context *ssl );
2541
2542 /**
2543 * \brief Set the list of allowed ciphersuites and the preference
2544 * order. First in the list has the highest preference.
2545 * (Overrides all version-specific lists)
2546 *
2547 * The ciphersuites array is not copied, and must remain
2548 * valid for the lifetime of the ssl_config.
2549 *
2550 * Note: The server uses its own preferences
2551 * over the preference of the client unless
2552 * MBEDTLS_SSL_SRV_RESPECT_CLIENT_PREFERENCE is defined!
2553 *
2554 * \param conf SSL configuration
2555 * \param ciphersuites 0-terminated list of allowed ciphersuites
2556 */
2557 void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf,
2558 const int *ciphersuites );
2559
2560 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
2561 #define MBEDTLS_SSL_UNEXPECTED_CID_IGNORE 0
2562 #define MBEDTLS_SSL_UNEXPECTED_CID_FAIL 1
2563 /**
2564 * \brief Specify the length of Connection IDs for incoming
2565 * encrypted DTLS records, as well as the behaviour
2566 * on unexpected CIDs.
2567 *
2568 * By default, the CID length is set to \c 0,
2569 * and unexpected CIDs are silently ignored.
2570 *
2571 * \param conf The SSL configuration to modify.
2572 * \param len The length in Bytes of the CID fields in encrypted
2573 * DTLS records using the CID mechanism. This must
2574 * not be larger than #MBEDTLS_SSL_CID_OUT_LEN_MAX.
2575 * \param ignore_other_cids This determines the stack's behaviour when
2576 * receiving a record with an unexpected CID.
2577 * Possible values are:
2578 * - #MBEDTLS_SSL_UNEXPECTED_CID_IGNORE
2579 * In this case, the record is silently ignored.
2580 * - #MBEDTLS_SSL_UNEXPECTED_CID_FAIL
2581 * In this case, the stack fails with the specific
2582 * error code #MBEDTLS_ERR_SSL_UNEXPECTED_CID.
2583 *
2584 * \note The CID specification allows implementations to either
2585 * use a common length for all incoming connection IDs or
2586 * allow variable-length incoming IDs. Mbed TLS currently
2587 * requires a common length for all connections sharing the
2588 * same SSL configuration; this allows simpler parsing of
2589 * record headers.
2590 *
2591 * \return \c 0 on success.
2592 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if \p own_cid_len
2593 * is too large.
2594 */
2595 int mbedtls_ssl_conf_cid( mbedtls_ssl_config *conf, size_t len,
2596 int ignore_other_cids );
2597 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
2598
2599 /**
2600 * \brief Set the list of allowed ciphersuites and the
2601 * preference order for a specific version of the protocol.
2602 * (Only useful on the server side)
2603 *
2604 * The ciphersuites array is not copied, and must remain
2605 * valid for the lifetime of the ssl_config.
2606 *
2607 * \param conf SSL configuration
2608 * \param ciphersuites 0-terminated list of allowed ciphersuites
2609 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3
2610 * supported)
2611 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
2612 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
2613 * MBEDTLS_SSL_MINOR_VERSION_3 supported)
2614 *
2615 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0
2616 * and MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
2617 */
2618 void mbedtls_ssl_conf_ciphersuites_for_version( mbedtls_ssl_config *conf,
2619 const int *ciphersuites,
2620 int major, int minor );
2621
2622 #if defined(MBEDTLS_X509_CRT_PARSE_C)
2623 /**
2624 * \brief Set the X.509 security profile used for verification
2625 *
2626 * \note The restrictions are enforced for all certificates in the
2627 * chain. However, signatures in the handshake are not covered
2628 * by this setting but by \b mbedtls_ssl_conf_sig_hashes().
2629 *
2630 * \param conf SSL configuration
2631 * \param profile Profile to use
2632 */
2633 void mbedtls_ssl_conf_cert_profile( mbedtls_ssl_config *conf,
2634 const mbedtls_x509_crt_profile *profile );
2635
2636 /**
2637 * \brief Set the data required to verify peer certificate
2638 *
2639 * \note See \c mbedtls_x509_crt_verify() for notes regarding the
2640 * parameters ca_chain (maps to trust_ca for that function)
2641 * and ca_crl.
2642 *
2643 * \param conf SSL configuration
2644 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
2645 * \param ca_crl trusted CA CRLs
2646 */
2647 void mbedtls_ssl_conf_ca_chain( mbedtls_ssl_config *conf,
2648 mbedtls_x509_crt *ca_chain,
2649 mbedtls_x509_crl *ca_crl );
2650
2651 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
2652 /**
2653 * \brief Set the trusted certificate callback.
2654 *
2655 * This API allows to register the set of trusted certificates
2656 * through a callback, instead of a linked list as configured
2657 * by mbedtls_ssl_conf_ca_chain().
2658 *
2659 * This is useful for example in contexts where a large number
2660 * of CAs are used, and the inefficiency of maintaining them
2661 * in a linked list cannot be tolerated. It is also useful when
2662 * the set of trusted CAs needs to be modified frequently.
2663 *
2664 * See the documentation of `mbedtls_x509_crt_ca_cb_t` for
2665 * more information.
2666 *
2667 * \param conf The SSL configuration to register the callback with.
2668 * \param f_ca_cb The trusted certificate callback to use when verifying
2669 * certificate chains.
2670 * \param p_ca_cb The context to be passed to \p f_ca_cb (for example,
2671 * a reference to a trusted CA database).
2672 *
2673 * \note This API is incompatible with mbedtls_ssl_conf_ca_chain():
2674 * Any call to this function overwrites the values set through
2675 * earlier calls to mbedtls_ssl_conf_ca_chain() or
2676 * mbedtls_ssl_conf_ca_cb().
2677 *
2678 * \note This API is incompatible with CA indication in
2679 * CertificateRequest messages: A server-side SSL context which
2680 * is bound to an SSL configuration that uses a CA callback
2681 * configured via mbedtls_ssl_conf_ca_cb(), and which requires
2682 * client authentication, will send an empty CA list in the
2683 * corresponding CertificateRequest message.
2684 *
2685 * \note This API is incompatible with mbedtls_ssl_set_hs_ca_chain():
2686 * If an SSL context is bound to an SSL configuration which uses
2687 * CA callbacks configured via mbedtls_ssl_conf_ca_cb(), then
2688 * calls to mbedtls_ssl_set_hs_ca_chain() have no effect.
2689 *
2690 * \note The use of this API disables the use of restartable ECC
2691 * during X.509 CRT signature verification (but doesn't affect
2692 * other uses).
2693 *
2694 * \warning This API is incompatible with the use of CRLs. Any call to
2695 * mbedtls_ssl_conf_ca_cb() unsets CRLs configured through
2696 * earlier calls to mbedtls_ssl_conf_ca_chain().
2697 *
2698 * \warning In multi-threaded environments, the callback \p f_ca_cb
2699 * must be thread-safe, and it is the user's responsibility
2700 * to guarantee this (for example through a mutex
2701 * contained in the callback context pointed to by \p p_ca_cb).
2702 */
2703 void mbedtls_ssl_conf_ca_cb( mbedtls_ssl_config *conf,
2704 mbedtls_x509_crt_ca_cb_t f_ca_cb,
2705 void *p_ca_cb );
2706 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
2707
2708 /**
2709 * \brief Set own certificate chain and private key
2710 *
2711 * \note own_cert should contain in order from the bottom up your
2712 * certificate chain. The top certificate (self-signed)
2713 * can be omitted.
2714 *
2715 * \note On server, this function can be called multiple times to
2716 * provision more than one cert/key pair (eg one ECDSA, one
2717 * RSA with SHA-256, one RSA with SHA-1). An adequate
2718 * certificate will be selected according to the client's
2719 * advertised capabilities. In case multiple certificates are
2720 * adequate, preference is given to the one set by the first
2721 * call to this function, then second, etc.
2722 *
2723 * \note On client, only the first call has any effect. That is,
2724 * only one client certificate can be provisioned. The
2725 * server's preferences in its CertficateRequest message will
2726 * be ignored and our only cert will be sent regardless of
2727 * whether it matches those preferences - the server can then
2728 * decide what it wants to do with it.
2729 *
2730 * \note The provided \p pk_key needs to match the public key in the
2731 * first certificate in \p own_cert, or all handshakes using
2732 * that certificate will fail. It is your responsibility
2733 * to ensure that; this function will not perform any check.
2734 * You may use mbedtls_pk_check_pair() in order to perform
2735 * this check yourself, but be aware that this function can
2736 * be computationally expensive on some key types.
2737 *
2738 * \param conf SSL configuration
2739 * \param own_cert own public certificate chain
2740 * \param pk_key own private key
2741 *
2742 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
2743 */
2744 int mbedtls_ssl_conf_own_cert( mbedtls_ssl_config *conf,
2745 mbedtls_x509_crt *own_cert,
2746 mbedtls_pk_context *pk_key );
2747 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2748
2749 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
2750 /**
2751 * \brief Configure a pre-shared key (PSK) and identity
2752 * to be used in PSK-based ciphersuites.
2753 *
2754 * \note This is mainly useful for clients. Servers will usually
2755 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
2756 *
2757 * \note A PSK set by \c mbedtls_ssl_set_hs_psk() in the PSK callback
2758 * takes precedence over a PSK configured by this function.
2759 *
2760 * \warning Currently, clients can only register a single pre-shared key.
2761 * Calling this function or mbedtls_ssl_conf_psk_opaque() more
2762 * than once will overwrite values configured in previous calls.
2763 * Support for setting multiple PSKs on clients and selecting
2764 * one based on the identity hint is not a planned feature,
2765 * but feedback is welcomed.
2766 *
2767 * \param conf The SSL configuration to register the PSK with.
2768 * \param psk The pointer to the pre-shared key to use.
2769 * \param psk_len The length of the pre-shared key in bytes.
2770 * \param psk_identity The pointer to the pre-shared key identity.
2771 * \param psk_identity_len The length of the pre-shared key identity
2772 * in bytes.
2773 *
2774 * \note The PSK and its identity are copied internally and
2775 * hence need not be preserved by the caller for the lifetime
2776 * of the SSL configuration.
2777 *
2778 * \return \c 0 if successful.
2779 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
2780 */
2781 int mbedtls_ssl_conf_psk( mbedtls_ssl_config *conf,
2782 const unsigned char *psk, size_t psk_len,
2783 const unsigned char *psk_identity, size_t psk_identity_len );
2784
2785 #if defined(MBEDTLS_USE_PSA_CRYPTO)
2786 /**
2787 * \brief Configure an opaque pre-shared key (PSK) and identity
2788 * to be used in PSK-based ciphersuites.
2789 *
2790 * \note This is mainly useful for clients. Servers will usually
2791 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
2792 *
2793 * \note An opaque PSK set by \c mbedtls_ssl_set_hs_psk_opaque() in
2794 * the PSK callback takes precedence over an opaque PSK
2795 * configured by this function.
2796 *
2797 * \warning Currently, clients can only register a single pre-shared key.
2798 * Calling this function or mbedtls_ssl_conf_psk() more than
2799 * once will overwrite values configured in previous calls.
2800 * Support for setting multiple PSKs on clients and selecting
2801 * one based on the identity hint is not a planned feature,
2802 * but feedback is welcomed.
2803 *
2804 * \param conf The SSL configuration to register the PSK with.
2805 * \param psk The identifier of the key slot holding the PSK.
2806 * Until \p conf is destroyed or this function is successfully
2807 * called again, the key slot \p psk must be populated with a
2808 * key of type PSA_ALG_CATEGORY_KEY_DERIVATION whose policy
2809 * allows its use for the key derivation algorithm applied
2810 * in the handshake.
2811 * \param psk_identity The pointer to the pre-shared key identity.
2812 * \param psk_identity_len The length of the pre-shared key identity
2813 * in bytes.
2814 *
2815 * \note The PSK identity hint is copied internally and hence need
2816 * not be preserved by the caller for the lifetime of the
2817 * SSL configuration.
2818 *
2819 * \return \c 0 if successful.
2820 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
2821 */
2822 int mbedtls_ssl_conf_psk_opaque( mbedtls_ssl_config *conf,
2823 psa_key_id_t psk,
2824 const unsigned char *psk_identity,
2825 size_t psk_identity_len );
2826 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2827
2828 /**
2829 * \brief Set the pre-shared Key (PSK) for the current handshake.
2830 *
2831 * \note This should only be called inside the PSK callback,
2832 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
2833 *
2834 * \note A PSK set by this function takes precedence over a PSK
2835 * configured by \c mbedtls_ssl_conf_psk().
2836 *
2837 * \param ssl The SSL context to configure a PSK for.
2838 * \param psk The pointer to the pre-shared key.
2839 * \param psk_len The length of the pre-shared key in bytes.
2840 *
2841 * \return \c 0 if successful.
2842 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
2843 */
2844 int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl,
2845 const unsigned char *psk, size_t psk_len );
2846
2847 #if defined(MBEDTLS_USE_PSA_CRYPTO)
2848 /**
2849 * \brief Set an opaque pre-shared Key (PSK) for the current handshake.
2850 *
2851 * \note This should only be called inside the PSK callback,
2852 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
2853 *
2854 * \note An opaque PSK set by this function takes precedence over an
2855 * opaque PSK configured by \c mbedtls_ssl_conf_psk_opaque().
2856 *
2857 * \param ssl The SSL context to configure a PSK for.
2858 * \param psk The identifier of the key slot holding the PSK.
2859 * For the duration of the current handshake, the key slot
2860 * must be populated with a key of type
2861 * PSA_ALG_CATEGORY_KEY_DERIVATION whose policy allows its
2862 * use for the key derivation algorithm
2863 * applied in the handshake.
2864 *
2865 * \return \c 0 if successful.
2866 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
2867 */
2868 int mbedtls_ssl_set_hs_psk_opaque( mbedtls_ssl_context *ssl,
2869 psa_key_id_t psk );
2870 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2871
2872 /**
2873 * \brief Set the PSK callback (server-side only).
2874 *
2875 * If set, the PSK callback is called for each
2876 * handshake where a PSK-based ciphersuite was negotiated.
2877 * The caller provides the identity received and wants to
2878 * receive the actual PSK data and length.
2879 *
2880 * The callback has the following parameters:
2881 * - \c void*: The opaque pointer \p p_psk.
2882 * - \c mbedtls_ssl_context*: The SSL context to which
2883 * the operation applies.
2884 * - \c const unsigned char*: The PSK identity
2885 * selected by the client.
2886 * - \c size_t: The length of the PSK identity
2887 * selected by the client.
2888 *
2889 * If a valid PSK identity is found, the callback should use
2890 * \c mbedtls_ssl_set_hs_psk() or
2891 * \c mbedtls_ssl_set_hs_psk_opaque()
2892 * on the SSL context to set the correct PSK and return \c 0.
2893 * Any other return value will result in a denied PSK identity.
2894 *
2895 * \note A dynamic PSK (i.e. set by the PSK callback) takes
2896 * precedence over a static PSK (i.e. set by
2897 * \c mbedtls_ssl_conf_psk() or
2898 * \c mbedtls_ssl_conf_psk_opaque()).
2899 * This means that if you set a PSK callback using this
2900 * function, you don't need to set a PSK using
2901 * \c mbedtls_ssl_conf_psk() or
2902 * \c mbedtls_ssl_conf_psk_opaque()).
2903 *
2904 * \param conf The SSL configuration to register the callback with.
2905 * \param f_psk The callback for selecting and setting the PSK based
2906 * in the PSK identity chosen by the client.
2907 * \param p_psk A pointer to an opaque structure to be passed to
2908 * the callback, for example a PSK store.
2909 */
2910 void mbedtls_ssl_conf_psk_cb( mbedtls_ssl_config *conf,
2911 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *,
2912 size_t),
2913 void *p_psk );
2914 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
2915
2916 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
2917
2918 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
2919
2920 #if defined(MBEDTLS_DEPRECATED_WARNING)
2921 #define MBEDTLS_DEPRECATED __attribute__((deprecated))
2922 #else
2923 #define MBEDTLS_DEPRECATED
2924 #endif
2925
2926 /**
2927 * \brief Set the Diffie-Hellman public P and G values,
2928 * read as hexadecimal strings (server-side only)
2929 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG])
2930 *
2931 * \param conf SSL configuration
2932 * \param dhm_P Diffie-Hellman-Merkle modulus
2933 * \param dhm_G Diffie-Hellman-Merkle generator
2934 *
2935 * \deprecated Superseded by \c mbedtls_ssl_conf_dh_param_bin.
2936 *
2937 * \return 0 if successful
2938 */
2939 MBEDTLS_DEPRECATED int mbedtls_ssl_conf_dh_param( mbedtls_ssl_config *conf,
2940 const char *dhm_P,
2941 const char *dhm_G );
2942
2943 #endif /* MBEDTLS_DEPRECATED_REMOVED */
2944
2945 /**
2946 * \brief Set the Diffie-Hellman public P and G values
2947 * from big-endian binary presentations.
2948 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN)
2949 *
2950 * \param conf SSL configuration
2951 * \param dhm_P Diffie-Hellman-Merkle modulus in big-endian binary form
2952 * \param P_len Length of DHM modulus
2953 * \param dhm_G Diffie-Hellman-Merkle generator in big-endian binary form
2954 * \param G_len Length of DHM generator
2955 *
2956 * \return 0 if successful
2957 */
2958 int mbedtls_ssl_conf_dh_param_bin( mbedtls_ssl_config *conf,
2959 const unsigned char *dhm_P, size_t P_len,
2960 const unsigned char *dhm_G, size_t G_len );
2961
2962 /**
2963 * \brief Set the Diffie-Hellman public P and G values,
2964 * read from existing context (server-side only)
2965 *
2966 * \param conf SSL configuration
2967 * \param dhm_ctx Diffie-Hellman-Merkle context
2968 *
2969 * \return 0 if successful
2970 */
2971 int mbedtls_ssl_conf_dh_param_ctx( mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx );
2972 #endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */
2973
2974 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
2975 /**
2976 * \brief Set the minimum length for Diffie-Hellman parameters.
2977 * (Client-side only.)
2978 * (Default: 1024 bits.)
2979 *
2980 * \param conf SSL configuration
2981 * \param bitlen Minimum bit length of the DHM prime
2982 */
2983 void mbedtls_ssl_conf_dhm_min_bitlen( mbedtls_ssl_config *conf,
2984 unsigned int bitlen );
2985 #endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */
2986
2987 #if defined(MBEDTLS_ECP_C)
2988 /**
2989 * \brief Set the allowed curves in order of preference.
2990 * (Default: all defined curves.)
2991 *
2992 * On server: this only affects selection of the ECDHE curve;
2993 * the curves used for ECDH and ECDSA are determined by the
2994 * list of available certificates instead.
2995 *
2996 * On client: this affects the list of curves offered for any
2997 * use. The server can override our preference order.
2998 *
2999 * Both sides: limits the set of curves accepted for use in
3000 * ECDHE and in the peer's end-entity certificate.
3001 *
3002 * \note This has no influence on which curves are allowed inside the
3003 * certificate chains, see \c mbedtls_ssl_conf_cert_profile()
3004 * for that. For the end-entity certificate however, the key
3005 * will be accepted only if it is allowed both by this list
3006 * and by the cert profile.
3007 *
3008 * \note This list should be ordered by decreasing preference
3009 * (preferred curve first).
3010 *
3011 * \param conf SSL configuration
3012 * \param curves Ordered list of allowed curves,
3013 * terminated by MBEDTLS_ECP_DP_NONE.
3014 */
3015 void mbedtls_ssl_conf_curves( mbedtls_ssl_config *conf,
3016 const mbedtls_ecp_group_id *curves );
3017 #endif /* MBEDTLS_ECP_C */
3018
3019 #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
3020 /**
3021 * \brief Set the allowed hashes for signatures during the handshake.
3022 * (Default: all available hashes except MD5.)
3023 *
3024 * \note This only affects which hashes are offered and can be used
3025 * for signatures during the handshake. Hashes for message
3026 * authentication and the TLS PRF are controlled by the
3027 * ciphersuite, see \c mbedtls_ssl_conf_ciphersuites(). Hashes
3028 * used for certificate signature are controlled by the
3029 * verification profile, see \c mbedtls_ssl_conf_cert_profile().
3030 *
3031 * \note This list should be ordered by decreasing preference
3032 * (preferred hash first).
3033 *
3034 * \param conf SSL configuration
3035 * \param hashes Ordered list of allowed signature hashes,
3036 * terminated by \c MBEDTLS_MD_NONE.
3037 */
3038 void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf,
3039 const int *hashes );
3040 #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
3041
3042 #if defined(MBEDTLS_X509_CRT_PARSE_C)
3043 /**
3044 * \brief Set or reset the hostname to check against the received
3045 * server certificate. It sets the ServerName TLS extension,
3046 * too, if that extension is enabled. (client-side only)
3047 *
3048 * \param ssl SSL context
3049 * \param hostname the server hostname, may be NULL to clear hostname
3050
3051 * \note Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN.
3052 *
3053 * \return 0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on
3054 * allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on
3055 * too long input hostname.
3056 *
3057 * Hostname set to the one provided on success (cleared
3058 * when NULL). On allocation failure hostname is cleared.
3059 * On too long input failure, old hostname is unchanged.
3060 */
3061 int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname );
3062 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3063
3064 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
3065 /**
3066 * \brief Set own certificate and key for the current handshake
3067 *
3068 * \note Same as \c mbedtls_ssl_conf_own_cert() but for use within
3069 * the SNI callback.
3070 *
3071 * \param ssl SSL context
3072 * \param own_cert own public certificate chain
3073 * \param pk_key own private key
3074 *
3075 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
3076 */
3077 int mbedtls_ssl_set_hs_own_cert( mbedtls_ssl_context *ssl,
3078 mbedtls_x509_crt *own_cert,
3079 mbedtls_pk_context *pk_key );
3080
3081 /**
3082 * \brief Set the data required to verify peer certificate for the
3083 * current handshake
3084 *
3085 * \note Same as \c mbedtls_ssl_conf_ca_chain() but for use within
3086 * the SNI callback.
3087 *
3088 * \param ssl SSL context
3089 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
3090 * \param ca_crl trusted CA CRLs
3091 */
3092 void mbedtls_ssl_set_hs_ca_chain( mbedtls_ssl_context *ssl,
3093 mbedtls_x509_crt *ca_chain,
3094 mbedtls_x509_crl *ca_crl );
3095
3096 /**
3097 * \brief Set authmode for the current handshake.
3098 *
3099 * \note Same as \c mbedtls_ssl_conf_authmode() but for use within
3100 * the SNI callback.
3101 *
3102 * \param ssl SSL context
3103 * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or
3104 * MBEDTLS_SSL_VERIFY_REQUIRED
3105 */
3106 void mbedtls_ssl_set_hs_authmode( mbedtls_ssl_context *ssl,
3107 int authmode );
3108
3109 /**
3110 * \brief Set server side ServerName TLS extension callback
3111 * (optional, server-side only).
3112 *
3113 * If set, the ServerName callback is called whenever the
3114 * server receives a ServerName TLS extension from the client
3115 * during a handshake. The ServerName callback has the
3116 * following parameters: (void *parameter, mbedtls_ssl_context *ssl,
3117 * const unsigned char *hostname, size_t len). If a suitable
3118 * certificate is found, the callback must set the
3119 * certificate(s) and key(s) to use with \c
3120 * mbedtls_ssl_set_hs_own_cert() (can be called repeatedly),
3121 * and may optionally adjust the CA and associated CRL with \c
3122 * mbedtls_ssl_set_hs_ca_chain() as well as the client
3123 * authentication mode with \c mbedtls_ssl_set_hs_authmode(),
3124 * then must return 0. If no matching name is found, the
3125 * callback must either set a default cert, or
3126 * return non-zero to abort the handshake at this point.
3127 *
3128 * \param conf SSL configuration
3129 * \param f_sni verification function
3130 * \param p_sni verification parameter
3131 */
3132 void mbedtls_ssl_conf_sni( mbedtls_ssl_config *conf,
3133 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *,
3134 size_t),
3135 void *p_sni );
3136 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
3137
3138 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
3139 /**
3140 * \brief Set the EC J-PAKE password for current handshake.
3141 *
3142 * \note An internal copy is made, and destroyed as soon as the
3143 * handshake is completed, or when the SSL context is reset or
3144 * freed.
3145 *
3146 * \note The SSL context needs to be already set up. The right place
3147 * to call this function is between \c mbedtls_ssl_setup() or
3148 * \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake().
3149 *
3150 * \param ssl SSL context
3151 * \param pw EC J-PAKE password (pre-shared secret)
3152 * \param pw_len length of pw in bytes
3153 *
3154 * \return 0 on success, or a negative error code.
3155 */
3156 int mbedtls_ssl_set_hs_ecjpake_password( mbedtls_ssl_context *ssl,
3157 const unsigned char *pw,
3158 size_t pw_len );
3159 #endif /*MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
3160
3161 #if defined(MBEDTLS_SSL_ALPN)
3162 /**
3163 * \brief Set the supported Application Layer Protocols.
3164 *
3165 * \param conf SSL configuration
3166 * \param protos Pointer to a NULL-terminated list of supported protocols,
3167 * in decreasing preference order. The pointer to the list is
3168 * recorded by the library for later reference as required, so
3169 * the lifetime of the table must be atleast as long as the
3170 * lifetime of the SSL configuration structure.
3171 *
3172 * \return 0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA.
3173 */
3174 int mbedtls_ssl_conf_alpn_protocols( mbedtls_ssl_config *conf, const char **protos );
3175
3176 /**
3177 * \brief Get the name of the negotiated Application Layer Protocol.
3178 * This function should be called after the handshake is
3179 * completed.
3180 *
3181 * \param ssl SSL context
3182 *
3183 * \return Protcol name, or NULL if no protocol was negotiated.
3184 */
3185 const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl );
3186 #endif /* MBEDTLS_SSL_ALPN */
3187
3188 #if defined(MBEDTLS_SSL_DTLS_SRTP)
3189 #if defined(MBEDTLS_DEBUG_C)
mbedtls_ssl_get_srtp_profile_as_string(mbedtls_ssl_srtp_profile profile)3190 static inline const char *mbedtls_ssl_get_srtp_profile_as_string( mbedtls_ssl_srtp_profile profile )
3191 {
3192 switch( profile )
3193 {
3194 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80:
3195 return( "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80" );
3196 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32:
3197 return( "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" );
3198 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80:
3199 return( "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80" );
3200 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32:
3201 return( "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32" );
3202 default: break;
3203 }
3204 return( "" );
3205 }
3206 #endif /* MBEDTLS_DEBUG_C */
3207 /**
3208 * \brief Manage support for mki(master key id) value
3209 * in use_srtp extension.
3210 * MKI is an optional part of SRTP used for key management
3211 * and re-keying. See RFC3711 section 3.1 for details.
3212 * The default value is
3213 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED.
3214 *
3215 * \param conf The SSL configuration to manage mki support.
3216 * \param support_mki_value Enable or disable mki usage. Values are
3217 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED
3218 * or #MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED.
3219 */
3220 void mbedtls_ssl_conf_srtp_mki_value_supported( mbedtls_ssl_config *conf,
3221 int support_mki_value );
3222
3223 /**
3224 * \brief Set the supported DTLS-SRTP protection profiles.
3225 *
3226 * \param conf SSL configuration
3227 * \param profiles Pointer to a List of MBEDTLS_TLS_SRTP_UNSET terminated
3228 * supported protection profiles
3229 * in decreasing preference order.
3230 * The pointer to the list is recorded by the library
3231 * for later reference as required, so the lifetime
3232 * of the table must be at least as long as the lifetime
3233 * of the SSL configuration structure.
3234 * The list must not hold more than
3235 * MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH elements
3236 * (excluding the terminating MBEDTLS_TLS_SRTP_UNSET).
3237 *
3238 * \return 0 on success
3239 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA when the list of
3240 * protection profiles is incorrect.
3241 */
3242 int mbedtls_ssl_conf_dtls_srtp_protection_profiles
3243 ( mbedtls_ssl_config *conf,
3244 const mbedtls_ssl_srtp_profile *profiles );
3245
3246 /**
3247 * \brief Set the mki_value for the current DTLS-SRTP session.
3248 *
3249 * \param ssl SSL context to use.
3250 * \param mki_value The MKI value to set.
3251 * \param mki_len The length of the MKI value.
3252 *
3253 * \note This function is relevant on client side only.
3254 * The server discovers the mki value during handshake.
3255 * A mki value set on server side using this function
3256 * is ignored.
3257 *
3258 * \return 0 on success
3259 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA
3260 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE
3261 */
3262 int mbedtls_ssl_dtls_srtp_set_mki_value( mbedtls_ssl_context *ssl,
3263 unsigned char *mki_value,
3264 uint16_t mki_len );
3265 /**
3266 * \brief Get the negotiated DTLS-SRTP informations:
3267 * Protection profile and MKI value.
3268 *
3269 * \warning This function must be called after the handshake is
3270 * completed. The value returned by this function must
3271 * not be trusted or acted upon before the handshake completes.
3272 *
3273 * \param ssl The SSL context to query.
3274 * \param dtls_srtp_info The negotiated DTLS-SRTP informations:
3275 * - Protection profile in use.
3276 * A direct mapping of the iana defined value for protection
3277 * profile on an uint16_t.
3278 http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
3279 * #MBEDTLS_TLS_SRTP_UNSET if the use of SRTP was not negotiated
3280 * or peer's Hello packet was not parsed yet.
3281 * - mki size and value( if size is > 0 ).
3282 */
3283 void mbedtls_ssl_get_dtls_srtp_negotiation_result( const mbedtls_ssl_context *ssl,
3284 mbedtls_dtls_srtp_info *dtls_srtp_info );
3285 #endif /* MBEDTLS_SSL_DTLS_SRTP */
3286
3287 /**
3288 * \brief Set the maximum supported version sent from the client side
3289 * and/or accepted at the server side
3290 * (Default: MBEDTLS_SSL_MAX_MAJOR_VERSION, MBEDTLS_SSL_MAX_MINOR_VERSION)
3291 *
3292 * \note This ignores ciphersuites from higher versions.
3293 *
3294 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and
3295 * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
3296 *
3297 * \param conf SSL configuration
3298 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
3299 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
3300 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
3301 * MBEDTLS_SSL_MINOR_VERSION_3 supported)
3302 */
3303 void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor );
3304
3305 /**
3306 * \brief Set the minimum accepted SSL/TLS protocol version
3307 * (Default: TLS 1.0)
3308 *
3309 * \note Input outside of the SSL_MAX_XXXXX_VERSION and
3310 * SSL_MIN_XXXXX_VERSION range is ignored.
3311 *
3312 * \note MBEDTLS_SSL_MINOR_VERSION_0 (SSL v3) should be avoided.
3313 *
3314 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and
3315 * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
3316 *
3317 * \param conf SSL configuration
3318 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
3319 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
3320 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
3321 * MBEDTLS_SSL_MINOR_VERSION_3 supported)
3322 */
3323 void mbedtls_ssl_conf_min_version( mbedtls_ssl_config *conf, int major, int minor );
3324
3325 #if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C)
3326 /**
3327 * \brief Set the fallback flag (client-side only).
3328 * (Default: MBEDTLS_SSL_IS_NOT_FALLBACK).
3329 *
3330 * \note Set to MBEDTLS_SSL_IS_FALLBACK when preparing a fallback
3331 * connection, that is a connection with max_version set to a
3332 * lower value than the value you're willing to use. Such
3333 * fallback connections are not recommended but are sometimes
3334 * necessary to interoperate with buggy (version-intolerant)
3335 * servers.
3336 *
3337 * \warning You should NOT set this to MBEDTLS_SSL_IS_FALLBACK for
3338 * non-fallback connections! This would appear to work for a
3339 * while, then cause failures when the server is upgraded to
3340 * support a newer TLS version.
3341 *
3342 * \param conf SSL configuration
3343 * \param fallback MBEDTLS_SSL_IS_NOT_FALLBACK or MBEDTLS_SSL_IS_FALLBACK
3344 */
3345 void mbedtls_ssl_conf_fallback( mbedtls_ssl_config *conf, char fallback );
3346 #endif /* MBEDTLS_SSL_FALLBACK_SCSV && MBEDTLS_SSL_CLI_C */
3347
3348 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
3349 /**
3350 * \brief Enable or disable Encrypt-then-MAC
3351 * (Default: MBEDTLS_SSL_ETM_ENABLED)
3352 *
3353 * \note This should always be enabled, it is a security
3354 * improvement, and should not cause any interoperability
3355 * issue (used only if the peer supports it too).
3356 *
3357 * \param conf SSL configuration
3358 * \param etm MBEDTLS_SSL_ETM_ENABLED or MBEDTLS_SSL_ETM_DISABLED
3359 */
3360 void mbedtls_ssl_conf_encrypt_then_mac( mbedtls_ssl_config *conf, char etm );
3361 #endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
3362
3363 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
3364 /**
3365 * \brief Enable or disable Extended Master Secret negotiation.
3366 * (Default: MBEDTLS_SSL_EXTENDED_MS_ENABLED)
3367 *
3368 * \note This should always be enabled, it is a security fix to the
3369 * protocol, and should not cause any interoperability issue
3370 * (used only if the peer supports it too).
3371 *
3372 * \param conf SSL configuration
3373 * \param ems MBEDTLS_SSL_EXTENDED_MS_ENABLED or MBEDTLS_SSL_EXTENDED_MS_DISABLED
3374 */
3375 void mbedtls_ssl_conf_extended_master_secret( mbedtls_ssl_config *conf, char ems );
3376 #endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
3377
3378 #if defined(MBEDTLS_ARC4_C)
3379 /**
3380 * \brief Disable or enable support for RC4
3381 * (Default: MBEDTLS_SSL_ARC4_DISABLED)
3382 *
3383 * \warning Use of RC4 in DTLS/TLS has been prohibited by RFC 7465
3384 * for security reasons. Use at your own risk.
3385 *
3386 * \note This function is deprecated and will be removed in
3387 * a future version of the library.
3388 * RC4 is disabled by default at compile time and needs to be
3389 * actively enabled for use with legacy systems.
3390 *
3391 * \param conf SSL configuration
3392 * \param arc4 MBEDTLS_SSL_ARC4_ENABLED or MBEDTLS_SSL_ARC4_DISABLED
3393 */
3394 void mbedtls_ssl_conf_arc4_support( mbedtls_ssl_config *conf, char arc4 );
3395 #endif /* MBEDTLS_ARC4_C */
3396
3397 #if defined(MBEDTLS_SSL_SRV_C)
3398 /**
3399 * \brief Whether to send a list of acceptable CAs in
3400 * CertificateRequest messages.
3401 * (Default: do send)
3402 *
3403 * \param conf SSL configuration
3404 * \param cert_req_ca_list MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or
3405 * MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED
3406 */
3407 void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf,
3408 char cert_req_ca_list );
3409 #endif /* MBEDTLS_SSL_SRV_C */
3410
3411 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
3412 /**
3413 * \brief Set the maximum fragment length to emit and/or negotiate.
3414 * (Typical: the smaller of #MBEDTLS_SSL_IN_CONTENT_LEN and
3415 * #MBEDTLS_SSL_OUT_CONTENT_LEN, usually `2^14` bytes)
3416 * (Server: set maximum fragment length to emit,
3417 * usually negotiated by the client during handshake)
3418 * (Client: set maximum fragment length to emit *and*
3419 * negotiate with the server during handshake)
3420 * (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE)
3421 *
3422 * \note On the client side, the maximum fragment length extension
3423 * *will not* be used, unless the maximum fragment length has
3424 * been set via this function to a value different than
3425 * #MBEDTLS_SSL_MAX_FRAG_LEN_NONE.
3426 *
3427 * \note With TLS, this currently only affects ApplicationData (sent
3428 * with \c mbedtls_ssl_read()), not handshake messages.
3429 * With DTLS, this affects both ApplicationData and handshake.
3430 *
3431 * \note This sets the maximum length for a record's payload,
3432 * excluding record overhead that will be added to it, see
3433 * \c mbedtls_ssl_get_record_expansion().
3434 *
3435 * \note For DTLS, it is also possible to set a limit for the total
3436 * size of daragrams passed to the transport layer, including
3437 * record overhead, see \c mbedtls_ssl_set_mtu().
3438 *
3439 * \param conf SSL configuration
3440 * \param mfl_code Code for maximum fragment length (allowed values:
3441 * MBEDTLS_SSL_MAX_FRAG_LEN_512, MBEDTLS_SSL_MAX_FRAG_LEN_1024,
3442 * MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096)
3443 *
3444 * \return 0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA
3445 */
3446 int mbedtls_ssl_conf_max_frag_len( mbedtls_ssl_config *conf, unsigned char mfl_code );
3447 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
3448
3449 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
3450 /**
3451 * \brief Activate negotiation of truncated HMAC
3452 * (Default: MBEDTLS_SSL_TRUNC_HMAC_DISABLED)
3453 *
3454 * \param conf SSL configuration
3455 * \param truncate Enable or disable (MBEDTLS_SSL_TRUNC_HMAC_ENABLED or
3456 * MBEDTLS_SSL_TRUNC_HMAC_DISABLED)
3457 */
3458 void mbedtls_ssl_conf_truncated_hmac( mbedtls_ssl_config *conf, int truncate );
3459 #endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
3460
3461 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
3462 /**
3463 * \brief Enable / Disable 1/n-1 record splitting
3464 * (Default: MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED)
3465 *
3466 * \note Only affects SSLv3 and TLS 1.0, not higher versions.
3467 * Does not affect non-CBC ciphersuites in any version.
3468 *
3469 * \param conf SSL configuration
3470 * \param split MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED or
3471 * MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED
3472 */
3473 void mbedtls_ssl_conf_cbc_record_splitting( mbedtls_ssl_config *conf, char split );
3474 #endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */
3475
3476 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
3477 /**
3478 * \brief Enable / Disable session tickets (client only).
3479 * (Default: MBEDTLS_SSL_SESSION_TICKETS_ENABLED.)
3480 *
3481 * \note On server, use \c mbedtls_ssl_conf_session_tickets_cb().
3482 *
3483 * \param conf SSL configuration
3484 * \param use_tickets Enable or disable (MBEDTLS_SSL_SESSION_TICKETS_ENABLED or
3485 * MBEDTLS_SSL_SESSION_TICKETS_DISABLED)
3486 */
3487 void mbedtls_ssl_conf_session_tickets( mbedtls_ssl_config *conf, int use_tickets );
3488 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
3489
3490 #if defined(MBEDTLS_SSL_RENEGOTIATION)
3491 /**
3492 * \brief Enable / Disable renegotiation support for connection when
3493 * initiated by peer
3494 * (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED)
3495 *
3496 * \warning It is recommended to always disable renegotation unless you
3497 * know you need it and you know what you're doing. In the
3498 * past, there have been several issues associated with
3499 * renegotiation or a poor understanding of its properties.
3500 *
3501 * \note Server-side, enabling renegotiation also makes the server
3502 * susceptible to a resource DoS by a malicious client.
3503 *
3504 * \param conf SSL configuration
3505 * \param renegotiation Enable or disable (MBEDTLS_SSL_RENEGOTIATION_ENABLED or
3506 * MBEDTLS_SSL_RENEGOTIATION_DISABLED)
3507 */
3508 void mbedtls_ssl_conf_renegotiation( mbedtls_ssl_config *conf, int renegotiation );
3509 #endif /* MBEDTLS_SSL_RENEGOTIATION */
3510
3511 /**
3512 * \brief Prevent or allow legacy renegotiation.
3513 * (Default: MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION)
3514 *
3515 * MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION allows connections to
3516 * be established even if the peer does not support
3517 * secure renegotiation, but does not allow renegotiation
3518 * to take place if not secure.
3519 * (Interoperable and secure option)
3520 *
3521 * MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION allows renegotiations
3522 * with non-upgraded peers. Allowing legacy renegotiation
3523 * makes the connection vulnerable to specific man in the
3524 * middle attacks. (See RFC 5746)
3525 * (Most interoperable and least secure option)
3526 *
3527 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE breaks off connections
3528 * if peer does not support secure renegotiation. Results
3529 * in interoperability issues with non-upgraded peers
3530 * that do not support renegotiation altogether.
3531 * (Most secure option, interoperability issues)
3532 *
3533 * \param conf SSL configuration
3534 * \param allow_legacy Prevent or allow (SSL_NO_LEGACY_RENEGOTIATION,
3535 * SSL_ALLOW_LEGACY_RENEGOTIATION or
3536 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE)
3537 */
3538 void mbedtls_ssl_conf_legacy_renegotiation( mbedtls_ssl_config *conf, int allow_legacy );
3539
3540 #if defined(MBEDTLS_SSL_RENEGOTIATION)
3541 /**
3542 * \brief Enforce renegotiation requests.
3543 * (Default: enforced, max_records = 16)
3544 *
3545 * When we request a renegotiation, the peer can comply or
3546 * ignore the request. This function allows us to decide
3547 * whether to enforce our renegotiation requests by closing
3548 * the connection if the peer doesn't comply.
3549 *
3550 * However, records could already be in transit from the peer
3551 * when the request is emitted. In order to increase
3552 * reliability, we can accept a number of records before the
3553 * expected handshake records.
3554 *
3555 * The optimal value is highly dependent on the specific usage
3556 * scenario.
3557 *
3558 * \note With DTLS and server-initiated renegotiation, the
3559 * HelloRequest is retransmited every time mbedtls_ssl_read() times
3560 * out or receives Application Data, until:
3561 * - max_records records have beens seen, if it is >= 0, or
3562 * - the number of retransmits that would happen during an
3563 * actual handshake has been reached.
3564 * Please remember the request might be lost a few times
3565 * if you consider setting max_records to a really low value.
3566 *
3567 * \warning On client, the grace period can only happen during
3568 * mbedtls_ssl_read(), as opposed to mbedtls_ssl_write() and mbedtls_ssl_renegotiate()
3569 * which always behave as if max_record was 0. The reason is,
3570 * if we receive application data from the server, we need a
3571 * place to write it, which only happens during mbedtls_ssl_read().
3572 *
3573 * \param conf SSL configuration
3574 * \param max_records Use MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to
3575 * enforce renegotiation, or a non-negative value to enforce
3576 * it but allow for a grace period of max_records records.
3577 */
3578 void mbedtls_ssl_conf_renegotiation_enforced( mbedtls_ssl_config *conf, int max_records );
3579
3580 /**
3581 * \brief Set record counter threshold for periodic renegotiation.
3582 * (Default: 2^48 - 1)
3583 *
3584 * Renegotiation is automatically triggered when a record
3585 * counter (outgoing or incoming) crosses the defined
3586 * threshold. The default value is meant to prevent the
3587 * connection from being closed when the counter is about to
3588 * reached its maximal value (it is not allowed to wrap).
3589 *
3590 * Lower values can be used to enforce policies such as "keys
3591 * must be refreshed every N packets with cipher X".
3592 *
3593 * The renegotiation period can be disabled by setting
3594 * conf->disable_renegotiation to
3595 * MBEDTLS_SSL_RENEGOTIATION_DISABLED.
3596 *
3597 * \note When the configured transport is
3598 * MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation
3599 * period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM,
3600 * the maximum renegotiation period is 2^64 - 1.
3601 *
3602 * \param conf SSL configuration
3603 * \param period The threshold value: a big-endian 64-bit number.
3604 */
3605 void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf,
3606 const unsigned char period[8] );
3607 #endif /* MBEDTLS_SSL_RENEGOTIATION */
3608
3609 /**
3610 * \brief Check if there is data already read from the
3611 * underlying transport but not yet processed.
3612 *
3613 * \param ssl SSL context
3614 *
3615 * \return 0 if nothing's pending, 1 otherwise.
3616 *
3617 * \note This is different in purpose and behaviour from
3618 * \c mbedtls_ssl_get_bytes_avail in that it considers
3619 * any kind of unprocessed data, not only unread
3620 * application data. If \c mbedtls_ssl_get_bytes
3621 * returns a non-zero value, this function will
3622 * also signal pending data, but the converse does
3623 * not hold. For example, in DTLS there might be
3624 * further records waiting to be processed from
3625 * the current underlying transport's datagram.
3626 *
3627 * \note If this function returns 1 (data pending), this
3628 * does not imply that a subsequent call to
3629 * \c mbedtls_ssl_read will provide any data;
3630 * e.g., the unprocessed data might turn out
3631 * to be an alert or a handshake message.
3632 *
3633 * \note This function is useful in the following situation:
3634 * If the SSL/TLS module successfully returns from an
3635 * operation - e.g. a handshake or an application record
3636 * read - and you're awaiting incoming data next, you
3637 * must not immediately idle on the underlying transport
3638 * to have data ready, but you need to check the value
3639 * of this function first. The reason is that the desired
3640 * data might already be read but not yet processed.
3641 * If, in contrast, a previous call to the SSL/TLS module
3642 * returned MBEDTLS_ERR_SSL_WANT_READ, it is not necessary
3643 * to call this function, as the latter error code entails
3644 * that all internal data has been processed.
3645 *
3646 */
3647 int mbedtls_ssl_check_pending( const mbedtls_ssl_context *ssl );
3648
3649 /**
3650 * \brief Return the number of application data bytes
3651 * remaining to be read from the current record.
3652 *
3653 * \param ssl SSL context
3654 *
3655 * \return How many bytes are available in the application
3656 * data record read buffer.
3657 *
3658 * \note When working over a datagram transport, this is
3659 * useful to detect the current datagram's boundary
3660 * in case \c mbedtls_ssl_read has written the maximal
3661 * amount of data fitting into the input buffer.
3662 *
3663 */
3664 size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl );
3665
3666 /**
3667 * \brief Return the result of the certificate verification
3668 *
3669 * \param ssl The SSL context to use.
3670 *
3671 * \return \c 0 if the certificate verification was successful.
3672 * \return \c -1u if the result is not available. This may happen
3673 * e.g. if the handshake aborts early, or a verification
3674 * callback returned a fatal error.
3675 * \return A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX
3676 * and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h.
3677 */
3678 uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl );
3679
3680 /**
3681 * \brief Return the name of the current ciphersuite
3682 *
3683 * \param ssl SSL context
3684 *
3685 * \return a string containing the ciphersuite name
3686 */
3687 const char *mbedtls_ssl_get_ciphersuite( const mbedtls_ssl_context *ssl );
3688
3689 /**
3690 * \brief Return the current SSL version (SSLv3/TLSv1/etc)
3691 *
3692 * \param ssl SSL context
3693 *
3694 * \return a string containing the SSL version
3695 */
3696 const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl );
3697
3698 /**
3699 * \brief Return the (maximum) number of bytes added by the record
3700 * layer: header + encryption/MAC overhead (inc. padding)
3701 *
3702 * \note This function is not available (always returns an error)
3703 * when record compression is enabled.
3704 *
3705 * \param ssl SSL context
3706 *
3707 * \return Current maximum record expansion in bytes, or
3708 * MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if compression is
3709 * enabled, which makes expansion much less predictable
3710 */
3711 int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl );
3712
3713 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
3714 /**
3715 * \brief Return the maximum fragment length (payload, in bytes) for
3716 * the output buffer. For the client, this is the configured
3717 * value. For the server, it is the minimum of two - the
3718 * configured value and the negotiated one.
3719 *
3720 * \sa mbedtls_ssl_conf_max_frag_len()
3721 * \sa mbedtls_ssl_get_max_record_payload()
3722 *
3723 * \param ssl SSL context
3724 *
3725 * \return Current maximum fragment length for the output buffer.
3726 */
3727 size_t mbedtls_ssl_get_output_max_frag_len( const mbedtls_ssl_context *ssl );
3728
3729 /**
3730 * \brief Return the maximum fragment length (payload, in bytes) for
3731 * the input buffer. This is the negotiated maximum fragment
3732 * length, or, if there is none, MBEDTLS_SSL_MAX_CONTENT_LEN.
3733 * If it is not defined either, the value is 2^14. This function
3734 * works as its predecessor, \c mbedtls_ssl_get_max_frag_len().
3735 *
3736 * \sa mbedtls_ssl_conf_max_frag_len()
3737 * \sa mbedtls_ssl_get_max_record_payload()
3738 *
3739 * \param ssl SSL context
3740 *
3741 * \return Current maximum fragment length for the output buffer.
3742 */
3743 size_t mbedtls_ssl_get_input_max_frag_len( const mbedtls_ssl_context *ssl );
3744
3745 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
3746
3747 #if defined(MBEDTLS_DEPRECATED_WARNING)
3748 #define MBEDTLS_DEPRECATED __attribute__((deprecated))
3749 #else
3750 #define MBEDTLS_DEPRECATED
3751 #endif
3752
3753 /**
3754 * \brief This function is a deprecated approach to getting the max
3755 * fragment length. Its an alias for
3756 * \c mbedtls_ssl_get_output_max_frag_len(), as the behaviour
3757 * is the same. See \c mbedtls_ssl_get_output_max_frag_len() for
3758 * more detail.
3759 *
3760 * \sa mbedtls_ssl_get_input_max_frag_len()
3761 * \sa mbedtls_ssl_get_output_max_frag_len()
3762 *
3763 * \param ssl SSL context
3764 *
3765 * \return Current maximum fragment length for the output buffer.
3766 */
3767 MBEDTLS_DEPRECATED size_t mbedtls_ssl_get_max_frag_len(
3768 const mbedtls_ssl_context *ssl );
3769 #endif /* MBEDTLS_DEPRECATED_REMOVED */
3770 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
3771
3772 /**
3773 * \brief Return the current maximum outgoing record payload in bytes.
3774 * This takes into account the config.h setting \c
3775 * MBEDTLS_SSL_OUT_CONTENT_LEN, the configured and negotiated
3776 * max fragment length extension if used, and for DTLS the
3777 * path MTU as configured and current record expansion.
3778 *
3779 * \note With DTLS, \c mbedtls_ssl_write() will return an error if
3780 * called with a larger length value.
3781 * With TLS, \c mbedtls_ssl_write() will fragment the input if
3782 * necessary and return the number of bytes written; it is up
3783 * to the caller to call \c mbedtls_ssl_write() again in
3784 * order to send the remaining bytes if any.
3785 *
3786 * \note This function is not available (always returns an error)
3787 * when record compression is enabled.
3788 *
3789 * \sa mbedtls_ssl_set_mtu()
3790 * \sa mbedtls_ssl_get_output_max_frag_len()
3791 * \sa mbedtls_ssl_get_input_max_frag_len()
3792 * \sa mbedtls_ssl_get_record_expansion()
3793 *
3794 * \param ssl SSL context
3795 *
3796 * \return Current maximum payload for an outgoing record,
3797 * or a negative error code.
3798 */
3799 int mbedtls_ssl_get_max_out_record_payload( const mbedtls_ssl_context *ssl );
3800
3801 #if defined(MBEDTLS_X509_CRT_PARSE_C)
3802 /**
3803 * \brief Return the peer certificate from the current connection.
3804 *
3805 * \param ssl The SSL context to use. This must be initialized and setup.
3806 *
3807 * \return The current peer certificate, if available.
3808 * The returned certificate is owned by the SSL context and
3809 * is valid only until the next call to the SSL API.
3810 * \return \c NULL if no peer certificate is available. This might
3811 * be because the chosen ciphersuite doesn't use CRTs
3812 * (PSK-based ciphersuites, for example), or because
3813 * #MBEDTLS_SSL_KEEP_PEER_CERTIFICATE has been disabled,
3814 * allowing the stack to free the peer's CRT to save memory.
3815 *
3816 * \note For one-time inspection of the peer's certificate during
3817 * the handshake, consider registering an X.509 CRT verification
3818 * callback through mbedtls_ssl_conf_verify() instead of calling
3819 * this function. Using mbedtls_ssl_conf_verify() also comes at
3820 * the benefit of allowing you to influence the verification
3821 * process, for example by masking expected and tolerated
3822 * verification failures.
3823 *
3824 * \warning You must not use the pointer returned by this function
3825 * after any further call to the SSL API, including
3826 * mbedtls_ssl_read() and mbedtls_ssl_write(); this is
3827 * because the pointer might change during renegotiation,
3828 * which happens transparently to the user.
3829 * If you want to use the certificate across API calls,
3830 * you must make a copy.
3831 */
3832 const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert( const mbedtls_ssl_context *ssl );
3833 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3834
3835 #if defined(MBEDTLS_SSL_CLI_C)
3836 /**
3837 * \brief Save session in order to resume it later (client-side only)
3838 * Session data is copied to presented session structure.
3839 *
3840 *
3841 * \param ssl SSL context
3842 * \param session session context
3843 *
3844 * \return 0 if successful,
3845 * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed,
3846 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or
3847 * arguments are otherwise invalid.
3848 *
3849 * \note Only the server certificate is copied, and not the full chain,
3850 * so you should not attempt to validate the certificate again
3851 * by calling \c mbedtls_x509_crt_verify() on it.
3852 * Instead, you should use the results from the verification
3853 * in the original handshake by calling \c mbedtls_ssl_get_verify_result()
3854 * after loading the session again into a new SSL context
3855 * using \c mbedtls_ssl_set_session().
3856 *
3857 * \note Once the session object is not needed anymore, you should
3858 * free it by calling \c mbedtls_ssl_session_free().
3859 *
3860 * \sa mbedtls_ssl_set_session()
3861 */
3862 int mbedtls_ssl_get_session( const mbedtls_ssl_context *ssl, mbedtls_ssl_session *session );
3863 #endif /* MBEDTLS_SSL_CLI_C */
3864
3865 /**
3866 * \brief Perform the SSL handshake
3867 *
3868 * \param ssl SSL context
3869 *
3870 * \return \c 0 if successful.
3871 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
3872 * if the handshake is incomplete and waiting for data to
3873 * be available for reading from or writing to the underlying
3874 * transport - in this case you must call this function again
3875 * when the underlying transport is ready for the operation.
3876 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
3877 * operation is in progress (see
3878 * mbedtls_ssl_conf_async_private_cb()) - in this case you
3879 * must call this function again when the operation is ready.
3880 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
3881 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
3882 * in this case you must call this function again to complete
3883 * the handshake when you're done attending other tasks.
3884 * \return #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED if DTLS is in use
3885 * and the client did not demonstrate reachability yet - in
3886 * this case you must stop using the context (see below).
3887 * \return Another SSL error code - in this case you must stop using
3888 * the context (see below).
3889 *
3890 * \warning If this function returns something other than
3891 * \c 0,
3892 * #MBEDTLS_ERR_SSL_WANT_READ,
3893 * #MBEDTLS_ERR_SSL_WANT_WRITE,
3894 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
3895 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
3896 * you must stop using the SSL context for reading or writing,
3897 * and either free it or call \c mbedtls_ssl_session_reset()
3898 * on it before re-using it for a new connection; the current
3899 * connection must be closed.
3900 *
3901 * \note If DTLS is in use, then you may choose to handle
3902 * #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging
3903 * purposes, as it is an expected return value rather than an
3904 * actual error, but you still need to reset/free the context.
3905 *
3906 * \note Remarks regarding event-driven DTLS:
3907 * If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
3908 * from the underlying transport layer is currently being processed,
3909 * and it is safe to idle until the timer or the underlying transport
3910 * signal a new event. This is not true for a successful handshake,
3911 * in which case the datagram of the underlying transport that is
3912 * currently being processed might or might not contain further
3913 * DTLS records.
3914 */
3915 int mbedtls_ssl_handshake( mbedtls_ssl_context *ssl );
3916
3917 /**
3918 * \brief Perform a single step of the SSL handshake
3919 *
3920 * \note The state of the context (ssl->state) will be at
3921 * the next state after this function returns \c 0. Do not
3922 * call this function if state is MBEDTLS_SSL_HANDSHAKE_OVER.
3923 *
3924 * \param ssl SSL context
3925 *
3926 * \return See mbedtls_ssl_handshake().
3927 *
3928 * \warning If this function returns something other than \c 0,
3929 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
3930 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
3931 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
3932 * the SSL context for reading or writing, and either free it
3933 * or call \c mbedtls_ssl_session_reset() on it before
3934 * re-using it for a new connection; the current connection
3935 * must be closed.
3936 */
3937 int mbedtls_ssl_handshake_step( mbedtls_ssl_context *ssl );
3938
3939 #if defined(MBEDTLS_SSL_RENEGOTIATION)
3940 /**
3941 * \brief Initiate an SSL renegotiation on the running connection.
3942 * Client: perform the renegotiation right now.
3943 * Server: request renegotiation, which will be performed
3944 * during the next call to mbedtls_ssl_read() if honored by
3945 * client.
3946 *
3947 * \param ssl SSL context
3948 *
3949 * \return 0 if successful, or any mbedtls_ssl_handshake() return
3950 * value except #MBEDTLS_ERR_SSL_CLIENT_RECONNECT that can't
3951 * happen during a renegotiation.
3952 *
3953 * \warning If this function returns something other than \c 0,
3954 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
3955 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
3956 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
3957 * the SSL context for reading or writing, and either free it
3958 * or call \c mbedtls_ssl_session_reset() on it before
3959 * re-using it for a new connection; the current connection
3960 * must be closed.
3961 *
3962 */
3963 int mbedtls_ssl_renegotiate( mbedtls_ssl_context *ssl );
3964 #endif /* MBEDTLS_SSL_RENEGOTIATION */
3965
3966 /**
3967 * \brief Read at most 'len' application data bytes
3968 *
3969 * \param ssl SSL context
3970 * \param buf buffer that will hold the data
3971 * \param len maximum number of bytes to read
3972 *
3973 * \return The (positive) number of bytes read if successful.
3974 * \return \c 0 if the read end of the underlying transport was closed
3975 * without sending a CloseNotify beforehand, which might happen
3976 * because of various reasons (internal error of an underlying
3977 * stack, non-conformant peer not sending a CloseNotify and
3978 * such) - in this case you must stop using the context
3979 * (see below).
3980 * \return #MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY if the underlying
3981 * transport is still functional, but the peer has
3982 * acknowledged to not send anything anymore.
3983 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
3984 * if the handshake is incomplete and waiting for data to
3985 * be available for reading from or writing to the underlying
3986 * transport - in this case you must call this function again
3987 * when the underlying transport is ready for the operation.
3988 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
3989 * operation is in progress (see
3990 * mbedtls_ssl_conf_async_private_cb()) - in this case you
3991 * must call this function again when the operation is ready.
3992 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
3993 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
3994 * in this case you must call this function again to complete
3995 * the handshake when you're done attending other tasks.
3996 * \return #MBEDTLS_ERR_SSL_CLIENT_RECONNECT if we're at the server
3997 * side of a DTLS connection and the client is initiating a
3998 * new connection using the same source port. See below.
3999 * \return Another SSL error code - in this case you must stop using
4000 * the context (see below).
4001 *
4002 * \warning If this function returns something other than
4003 * a positive value,
4004 * #MBEDTLS_ERR_SSL_WANT_READ,
4005 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4006 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
4007 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
4008 * #MBEDTLS_ERR_SSL_CLIENT_RECONNECT,
4009 * you must stop using the SSL context for reading or writing,
4010 * and either free it or call \c mbedtls_ssl_session_reset()
4011 * on it before re-using it for a new connection; the current
4012 * connection must be closed.
4013 *
4014 * \note When this function returns #MBEDTLS_ERR_SSL_CLIENT_RECONNECT
4015 * (which can only happen server-side), it means that a client
4016 * is initiating a new connection using the same source port.
4017 * You can either treat that as a connection close and wait
4018 * for the client to resend a ClientHello, or directly
4019 * continue with \c mbedtls_ssl_handshake() with the same
4020 * context (as it has been reset internally). Either way, you
4021 * must make sure this is seen by the application as a new
4022 * connection: application state, if any, should be reset, and
4023 * most importantly the identity of the client must be checked
4024 * again. WARNING: not validating the identity of the client
4025 * again, or not transmitting the new identity to the
4026 * application layer, would allow authentication bypass!
4027 *
4028 * \note Remarks regarding event-driven DTLS:
4029 * - If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
4030 * from the underlying transport layer is currently being processed,
4031 * and it is safe to idle until the timer or the underlying transport
4032 * signal a new event.
4033 * - This function may return MBEDTLS_ERR_SSL_WANT_READ even if data was
4034 * initially available on the underlying transport, as this data may have
4035 * been only e.g. duplicated messages or a renegotiation request.
4036 * Therefore, you must be prepared to receive MBEDTLS_ERR_SSL_WANT_READ even
4037 * when reacting to an incoming-data event from the underlying transport.
4038 * - On success, the datagram of the underlying transport that is currently
4039 * being processed may contain further DTLS records. You should call
4040 * \c mbedtls_ssl_check_pending to check for remaining records.
4041 *
4042 */
4043 int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len );
4044
4045 /**
4046 * \brief Try to write exactly 'len' application data bytes
4047 *
4048 * \warning This function will do partial writes in some cases. If the
4049 * return value is non-negative but less than length, the
4050 * function must be called again with updated arguments:
4051 * buf + ret, len - ret (if ret is the return value) until
4052 * it returns a value equal to the last 'len' argument.
4053 *
4054 * \param ssl SSL context
4055 * \param buf buffer holding the data
4056 * \param len how many bytes must be written
4057 *
4058 * \return The (non-negative) number of bytes actually written if
4059 * successful (may be less than \p len).
4060 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4061 * if the handshake is incomplete and waiting for data to
4062 * be available for reading from or writing to the underlying
4063 * transport - in this case you must call this function again
4064 * when the underlying transport is ready for the operation.
4065 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4066 * operation is in progress (see
4067 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4068 * must call this function again when the operation is ready.
4069 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4070 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4071 * in this case you must call this function again to complete
4072 * the handshake when you're done attending other tasks.
4073 * \return Another SSL error code - in this case you must stop using
4074 * the context (see below).
4075 *
4076 * \warning If this function returns something other than
4077 * a non-negative value,
4078 * #MBEDTLS_ERR_SSL_WANT_READ,
4079 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4080 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4081 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
4082 * you must stop using the SSL context for reading or writing,
4083 * and either free it or call \c mbedtls_ssl_session_reset()
4084 * on it before re-using it for a new connection; the current
4085 * connection must be closed.
4086 *
4087 * \note When this function returns #MBEDTLS_ERR_SSL_WANT_WRITE/READ,
4088 * it must be called later with the *same* arguments,
4089 * until it returns a value greater that or equal to 0. When
4090 * the function returns #MBEDTLS_ERR_SSL_WANT_WRITE there may be
4091 * some partial data in the output buffer, however this is not
4092 * yet sent.
4093 *
4094 * \note If the requested length is greater than the maximum
4095 * fragment length (either the built-in limit or the one set
4096 * or negotiated with the peer), then:
4097 * - with TLS, less bytes than requested are written.
4098 * - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned.
4099 * \c mbedtls_ssl_get_output_max_frag_len() may be used to
4100 * query the active maximum fragment length.
4101 *
4102 * \note Attempting to write 0 bytes will result in an empty TLS
4103 * application record being sent.
4104 */
4105 int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len );
4106
4107 /**
4108 * \brief Send an alert message
4109 *
4110 * \param ssl SSL context
4111 * \param level The alert level of the message
4112 * (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL)
4113 * \param message The alert message (SSL_ALERT_MSG_*)
4114 *
4115 * \return 0 if successful, or a specific SSL error code.
4116 *
4117 * \note If this function returns something other than 0 or
4118 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
4119 * the SSL context for reading or writing, and either free it or
4120 * call \c mbedtls_ssl_session_reset() on it before re-using it
4121 * for a new connection; the current connection must be closed.
4122 */
4123 int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl,
4124 unsigned char level,
4125 unsigned char message );
4126 /**
4127 * \brief Notify the peer that the connection is being closed
4128 *
4129 * \param ssl SSL context
4130 *
4131 * \return 0 if successful, or a specific SSL error code.
4132 *
4133 * \note If this function returns something other than 0 or
4134 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
4135 * the SSL context for reading or writing, and either free it or
4136 * call \c mbedtls_ssl_session_reset() on it before re-using it
4137 * for a new connection; the current connection must be closed.
4138 */
4139 int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl );
4140
4141 /**
4142 * \brief Free referenced items in an SSL context and clear memory
4143 *
4144 * \param ssl SSL context
4145 */
4146 void mbedtls_ssl_free( mbedtls_ssl_context *ssl );
4147
4148 #if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION)
4149 /**
4150 * \brief Save an active connection as serialized data in a buffer.
4151 * This allows the freeing or re-using of the SSL context
4152 * while still picking up the connection later in a way that
4153 * it entirely transparent to the peer.
4154 *
4155 * \see mbedtls_ssl_context_load()
4156 *
4157 * \note This feature is currently only available under certain
4158 * conditions, see the documentation of the return value
4159 * #MBEDTLS_ERR_SSL_BAD_INPUT_DATA for details.
4160 *
4161 * \note When this function succeeds, it calls
4162 * mbedtls_ssl_session_reset() on \p ssl which as a result is
4163 * no longer associated with the connection that has been
4164 * serialized. This avoids creating copies of the connection
4165 * state. You're then free to either re-use the context
4166 * structure for a different connection, or call
4167 * mbedtls_ssl_free() on it. See the documentation of
4168 * mbedtls_ssl_session_reset() for more details.
4169 *
4170 * \param ssl The SSL context to save. On success, it is no longer
4171 * associated with the connection that has been serialized.
4172 * \param buf The buffer to write the serialized data to. It must be a
4173 * writeable buffer of at least \p buf_len bytes, or may be \c
4174 * NULL if \p buf_len is \c 0.
4175 * \param buf_len The number of bytes available for writing in \p buf.
4176 * \param olen The size in bytes of the data that has been or would have
4177 * been written. It must point to a valid \c size_t.
4178 *
4179 * \note \p olen is updated to the correct value regardless of
4180 * whether \p buf_len was large enough. This makes it possible
4181 * to determine the necessary size by calling this function
4182 * with \p buf set to \c NULL and \p buf_len to \c 0. However,
4183 * the value of \p olen is only guaranteed to be correct when
4184 * the function returns #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL or
4185 * \c 0. If the return value is different, then the value of
4186 * \p olen is undefined.
4187 *
4188 * \return \c 0 if successful.
4189 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
4190 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed
4191 * while reseting the context.
4192 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if a handshake is in
4193 * progress, or there is pending data for reading or sending,
4194 * or the connection does not use DTLS 1.2 with an AEAD
4195 * ciphersuite, or renegotiation is enabled.
4196 */
4197 int mbedtls_ssl_context_save( mbedtls_ssl_context *ssl,
4198 unsigned char *buf,
4199 size_t buf_len,
4200 size_t *olen );
4201
4202 /**
4203 * \brief Load serialized connection data to an SSL context.
4204 *
4205 * \see mbedtls_ssl_context_save()
4206 *
4207 * \warning The same serialized data must never be loaded into more
4208 * that one context. In order to ensure that, after
4209 * successfully loading serialized data to an SSL context, you
4210 * should immediately destroy or invalidate all copies of the
4211 * serialized data that was loaded. Loading the same data in
4212 * more than one context would cause severe security failures
4213 * including but not limited to loss of confidentiality.
4214 *
4215 * \note Before calling this function, the SSL context must be
4216 * prepared in one of the two following ways. The first way is
4217 * to take a context freshly initialised with
4218 * mbedtls_ssl_init() and call mbedtls_ssl_setup() on it with
4219 * the same ::mbedtls_ssl_config structure that was used in
4220 * the original connection. The second way is to
4221 * call mbedtls_ssl_session_reset() on a context that was
4222 * previously prepared as above but used in the meantime.
4223 * Either way, you must not use the context to perform a
4224 * handshake between calling mbedtls_ssl_setup() or
4225 * mbedtls_ssl_session_reset() and calling this function. You
4226 * may however call other setter functions in that time frame
4227 * as indicated in the note below.
4228 *
4229 * \note Before or after calling this function successfully, you
4230 * also need to configure some connection-specific callbacks
4231 * and settings before you can use the connection again
4232 * (unless they were already set before calling
4233 * mbedtls_ssl_session_reset() and the values are suitable for
4234 * the present connection). Specifically, you want to call
4235 * at least mbedtls_ssl_set_bio() and
4236 * mbedtls_ssl_set_timer_cb(). All other SSL setter functions
4237 * are not necessary to call, either because they're only used
4238 * in handshakes, or because the setting is already saved. You
4239 * might choose to call them anyway, for example in order to
4240 * share code between the cases of establishing a new
4241 * connection and the case of loading an already-established
4242 * connection.
4243 *
4244 * \note If you have new information about the path MTU, you want to
4245 * call mbedtls_ssl_set_mtu() after calling this function, as
4246 * otherwise this function would overwrite your
4247 * newly-configured value with the value that was active when
4248 * the context was saved.
4249 *
4250 * \note When this function returns an error code, it calls
4251 * mbedtls_ssl_free() on \p ssl. In this case, you need to
4252 * prepare the context with the usual sequence starting with a
4253 * call to mbedtls_ssl_init() if you want to use it again.
4254 *
4255 * \param ssl The SSL context structure to be populated. It must have
4256 * been prepared as described in the note above.
4257 * \param buf The buffer holding the serialized connection data. It must
4258 * be a readable buffer of at least \p len bytes.
4259 * \param len The size of the serialized data in bytes.
4260 *
4261 * \return \c 0 if successful.
4262 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
4263 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
4264 * comes from a different Mbed TLS version or build.
4265 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
4266 */
4267 int mbedtls_ssl_context_load( mbedtls_ssl_context *ssl,
4268 const unsigned char *buf,
4269 size_t len );
4270 #endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */
4271
4272 /**
4273 * \brief Initialize an SSL configuration context
4274 * Just makes the context ready for
4275 * mbedtls_ssl_config_defaults() or mbedtls_ssl_config_free().
4276 *
4277 * \note You need to call mbedtls_ssl_config_defaults() unless you
4278 * manually set all of the relevant fields yourself.
4279 *
4280 * \param conf SSL configuration context
4281 */
4282 void mbedtls_ssl_config_init( mbedtls_ssl_config *conf );
4283
4284 /**
4285 * \brief Load reasonnable default SSL configuration values.
4286 * (You need to call mbedtls_ssl_config_init() first.)
4287 *
4288 * \param conf SSL configuration context
4289 * \param endpoint MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
4290 * \param transport MBEDTLS_SSL_TRANSPORT_STREAM for TLS, or
4291 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS
4292 * \param preset a MBEDTLS_SSL_PRESET_XXX value
4293 *
4294 * \note See \c mbedtls_ssl_conf_transport() for notes on DTLS.
4295 *
4296 * \return 0 if successful, or
4297 * MBEDTLS_ERR_XXX_ALLOC_FAILED on memory allocation error.
4298 */
4299 int mbedtls_ssl_config_defaults( mbedtls_ssl_config *conf,
4300 int endpoint, int transport, int preset );
4301
4302 /**
4303 * \brief Free an SSL configuration context
4304 *
4305 * \param conf SSL configuration context
4306 */
4307 void mbedtls_ssl_config_free( mbedtls_ssl_config *conf );
4308
4309 /**
4310 * \brief Initialize SSL session structure
4311 *
4312 * \param session SSL session
4313 */
4314 void mbedtls_ssl_session_init( mbedtls_ssl_session *session );
4315
4316 /**
4317 * \brief Free referenced items in an SSL session including the
4318 * peer certificate and clear memory
4319 *
4320 * \note A session object can be freed even if the SSL context
4321 * that was used to retrieve the session is still in use.
4322 *
4323 * \param session SSL session
4324 */
4325 void mbedtls_ssl_session_free( mbedtls_ssl_session *session );
4326
4327 /**
4328 * \brief TLS-PRF function for key derivation.
4329 *
4330 * \param prf The tls_prf type funtion type to be used.
4331 * \param secret Secret for the key derivation function.
4332 * \param slen Length of the secret.
4333 * \param label String label for the key derivation function,
4334 * terminated with null character.
4335 * \param random Random bytes.
4336 * \param rlen Length of the random bytes buffer.
4337 * \param dstbuf The buffer holding the derived key.
4338 * \param dlen Length of the output buffer.
4339 *
4340 * \return 0 on sucess. An SSL specific error on failure.
4341 */
4342 int mbedtls_ssl_tls_prf( const mbedtls_tls_prf_types prf,
4343 const unsigned char *secret, size_t slen,
4344 const char *label,
4345 const unsigned char *random, size_t rlen,
4346 unsigned char *dstbuf, size_t dlen );
4347
4348 #ifdef __cplusplus
4349 }
4350 #endif
4351
4352 #endif /* ssl.h */
4353
