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 \
58 "Record compression support via MBEDTLS_ZLIB_SUPPORT is deprecated and will be removed in the next major revision of the library"
59#endif
60
61#if defined(MBEDTLS_DEPRECATED_REMOVED)
62#error \
63 "Record compression support via MBEDTLS_ZLIB_SUPPORT is deprecated and cannot be used if MBEDTLS_DEPRECATED_REMOVED is set"
64#endif
65
66#include "zlib.h"
67#endif
68
69#if defined(MBEDTLS_HAVE_TIME)
70#include "mbedtls/platform_time.h"
71#endif
72
73#if defined(MBEDTLS_USE_PSA_CRYPTO)
74#include "psa/crypto.h"
75#endif /* MBEDTLS_USE_PSA_CRYPTO */
76
77/*
78 * SSL Error codes
79 */
80/** The requested feature is not available. */
81#define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE -0x7080
82/** Bad input parameters to function. */
83#define MBEDTLS_ERR_SSL_BAD_INPUT_DATA -0x7100
84/** Verification of the message MAC failed. */
85#define MBEDTLS_ERR_SSL_INVALID_MAC -0x7180
86/** An invalid SSL record was received. */
87#define MBEDTLS_ERR_SSL_INVALID_RECORD -0x7200
88/** The connection indicated an EOF. */
89#define MBEDTLS_ERR_SSL_CONN_EOF -0x7280
90/** An unknown cipher was received. */
91#define MBEDTLS_ERR_SSL_UNKNOWN_CIPHER -0x7300
92/** The server has no ciphersuites in common with the client. */
93#define MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN -0x7380
94/** No RNG was provided to the SSL module. */
95#define MBEDTLS_ERR_SSL_NO_RNG -0x7400
96/** No client certification received from the client, but required by the authentication mode. */
97#define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE -0x7480
98/** Our own certificate(s) is/are too large to send in an SSL message. */
99#define MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE -0x7500
100/** The own certificate is not set, but needed by the server. */
101#define MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED -0x7580
102/** The own private key or pre-shared key is not set, but needed. */
103#define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED -0x7600
104/** No CA Chain is set, but required to operate. */
105#define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED -0x7680
106/** An unexpected message was received from our peer. */
107#define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE -0x7700
108/** A fatal alert message was received from our peer. */
109#define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE -0x7780
110/** Verification of our peer failed. */
111#define MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED -0x7800
112/** The peer notified us that the connection is going to be closed. */
113#define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY -0x7880
114/** Processing of the ClientHello handshake message failed. */
115#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO -0x7900
116/** Processing of the ServerHello handshake message failed. */
117#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO -0x7980
118/** Processing of the Certificate handshake message failed. */
119#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE -0x7A00
120/** Processing of the CertificateRequest handshake message failed. */
121#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST -0x7A80
122/** Processing of the ServerKeyExchange handshake message failed. */
123#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE -0x7B00
124/** Processing of the ServerHelloDone handshake message failed. */
125#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE -0x7B80
126/** Processing of the ClientKeyExchange handshake message failed. */
127#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE -0x7C00
128/** Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Read Public. */
129#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP -0x7C80
130/** Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Calculate Secret. */
131#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_CS -0x7D00
132/** Processing of the CertificateVerify handshake message failed. */
133#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY -0x7D80
134/** Processing of the ChangeCipherSpec handshake message failed. */
135#define MBEDTLS_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC -0x7E00
136/** Processing of the Finished handshake message failed. */
137#define MBEDTLS_ERR_SSL_BAD_HS_FINISHED -0x7E80
138/** Memory allocation failed */
139#define MBEDTLS_ERR_SSL_ALLOC_FAILED -0x7F00
140/** Hardware acceleration function returned with error */
141#define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED -0x7F80
142/** Hardware acceleration function skipped / left alone data */
143#define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH -0x6F80
144/** Processing of the compression / decompression failed */
145#define MBEDTLS_ERR_SSL_COMPRESSION_FAILED -0x6F00
146/** Handshake protocol not within min/max boundaries */
147#define MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION -0x6E80
148/** Processing of the NewSessionTicket handshake message failed. */
149#define MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET -0x6E00
150/** Session ticket has expired. */
151#define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED -0x6D80
152/** Public key type mismatch (eg, asked for RSA key exchange and presented EC key) */
153#define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH -0x6D00
154/** Unknown identity received (eg, PSK identity) */
155#define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY -0x6C80
156/** Internal error (eg, unexpected failure in lower-level module) */
157#define MBEDTLS_ERR_SSL_INTERNAL_ERROR -0x6C00
158/** A counter would wrap (eg, too many messages exchanged). */
159#define MBEDTLS_ERR_SSL_COUNTER_WRAPPING -0x6B80
160/** Unexpected message at ServerHello in renegotiation. */
161#define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO -0x6B00
162/** DTLS client must retry for hello verification */
163#define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED -0x6A80
164/** A buffer is too small to receive or write a message */
165#define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL -0x6A00
166/** None of the common ciphersuites is usable (eg, no suitable certificate, see debug messages). */
167#define MBEDTLS_ERR_SSL_NO_USABLE_CIPHERSUITE -0x6980
168/** No data of requested type currently available on underlying transport. */
169#define MBEDTLS_ERR_SSL_WANT_READ -0x6900
170/** Connection requires a write call. */
171#define MBEDTLS_ERR_SSL_WANT_WRITE -0x6880
172/** The operation timed out. */
173#define MBEDTLS_ERR_SSL_TIMEOUT -0x6800
174/** The client initiated a reconnect from the same port. */
175#define MBEDTLS_ERR_SSL_CLIENT_RECONNECT -0x6780
176/** Record header looks valid but is not expected. */
177#define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD -0x6700
178/** The alert message received indicates a non-fatal error. */
179#define MBEDTLS_ERR_SSL_NON_FATAL -0x6680
180/** Couldn't set the hash for verifying CertificateVerify */
181#define MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH -0x6600
182/** Internal-only message signaling that further message-processing should be done */
183#define MBEDTLS_ERR_SSL_CONTINUE_PROCESSING -0x6580
184/** The asynchronous operation is not completed yet. */
185#define MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS -0x6500
186/** Internal-only message signaling that a message arrived early. */
187#define MBEDTLS_ERR_SSL_EARLY_MESSAGE -0x6480
188/** An encrypted DTLS-frame with an unexpected CID was received. */
189#define MBEDTLS_ERR_SSL_UNEXPECTED_CID -0x6000
190/** An operation failed due to an unexpected version or configuration. */
191#define MBEDTLS_ERR_SSL_VERSION_MISMATCH -0x5F00
192/** A cryptographic operation is in progress. Try again later. */
193#define MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS -0x7000
194/** Invalid value in SSL config */
195#define MBEDTLS_ERR_SSL_BAD_CONFIG -0x5E80
196
197/*
198 * Various constants
199 */
200#define MBEDTLS_SSL_MAJOR_VERSION_3 3
201#define MBEDTLS_SSL_MINOR_VERSION_0 0 /*!< SSL v3.0 */
202#define MBEDTLS_SSL_MINOR_VERSION_1 1 /*!< TLS v1.0 */
203#define MBEDTLS_SSL_MINOR_VERSION_2 2 /*!< TLS v1.1 */
204#define MBEDTLS_SSL_MINOR_VERSION_3 3 /*!< TLS v1.2 */
205#define MBEDTLS_SSL_MINOR_VERSION_4 4 /*!< TLS v1.3 (experimental) */
206
207#define MBEDTLS_SSL_TRANSPORT_STREAM 0 /*!< TLS */
208#define MBEDTLS_SSL_TRANSPORT_DATAGRAM 1 /*!< DTLS */
209
210#define MBEDTLS_SSL_MAX_HOST_NAME_LEN 255 /*!< Maximum host name defined in RFC 1035 */
211#define MBEDTLS_SSL_MAX_ALPN_NAME_LEN 255 /*!< Maximum size in bytes of a protocol name in alpn ext., RFC 7301 */
212
213#define MBEDTLS_SSL_MAX_ALPN_LIST_LEN 65535 /*!< Maximum size in bytes of list in alpn ext., RFC 7301 */
214
215/* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
216 * NONE must be zero so that memset()ing structure to zero works */
217#define MBEDTLS_SSL_MAX_FRAG_LEN_NONE 0 /*!< don't use this extension */
218#define MBEDTLS_SSL_MAX_FRAG_LEN_512 1 /*!< MaxFragmentLength 2^9 */
219#define MBEDTLS_SSL_MAX_FRAG_LEN_1024 2 /*!< MaxFragmentLength 2^10 */
220#define MBEDTLS_SSL_MAX_FRAG_LEN_2048 3 /*!< MaxFragmentLength 2^11 */
221#define MBEDTLS_SSL_MAX_FRAG_LEN_4096 4 /*!< MaxFragmentLength 2^12 */
222#define MBEDTLS_SSL_MAX_FRAG_LEN_INVALID 5 /*!< first invalid value */
223
224#define MBEDTLS_SSL_IS_CLIENT 0
225#define MBEDTLS_SSL_IS_SERVER 1
226
227#define MBEDTLS_SSL_IS_NOT_FALLBACK 0
228#define MBEDTLS_SSL_IS_FALLBACK 1
229
230#define MBEDTLS_SSL_EXTENDED_MS_DISABLED 0
231#define MBEDTLS_SSL_EXTENDED_MS_ENABLED 1
232
233#define MBEDTLS_SSL_CID_DISABLED 0
234#define MBEDTLS_SSL_CID_ENABLED 1
235
236#define MBEDTLS_SSL_ETM_DISABLED 0
237#define MBEDTLS_SSL_ETM_ENABLED 1
238
239#define MBEDTLS_SSL_COMPRESS_NULL 0
240#define MBEDTLS_SSL_COMPRESS_DEFLATE 1
241
242#define MBEDTLS_SSL_VERIFY_NONE 0
243#define MBEDTLS_SSL_VERIFY_OPTIONAL 1
244#define MBEDTLS_SSL_VERIFY_REQUIRED 2
245#define MBEDTLS_SSL_VERIFY_UNSET 3 /* Used only for sni_authmode */
246
247#define MBEDTLS_SSL_LEGACY_RENEGOTIATION 0
248#define MBEDTLS_SSL_SECURE_RENEGOTIATION 1
249
250#define MBEDTLS_SSL_RENEGOTIATION_DISABLED 0
251#define MBEDTLS_SSL_RENEGOTIATION_ENABLED 1
252
253#define MBEDTLS_SSL_ANTI_REPLAY_DISABLED 0
254#define MBEDTLS_SSL_ANTI_REPLAY_ENABLED 1
255
256#define MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED -1
257#define MBEDTLS_SSL_RENEGO_MAX_RECORDS_DEFAULT 16
258
259#define MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION 0
260#define MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION 1
261#define MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE 2
262
263#define MBEDTLS_SSL_TRUNC_HMAC_DISABLED 0
264#define MBEDTLS_SSL_TRUNC_HMAC_ENABLED 1
265#define MBEDTLS_SSL_TRUNCATED_HMAC_LEN 10 /* 80 bits, rfc 6066 section 7 */
266
267#define MBEDTLS_SSL_SESSION_TICKETS_DISABLED 0
268#define MBEDTLS_SSL_SESSION_TICKETS_ENABLED 1
269
270#define MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED 0
271#define MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED 1
272
273#define MBEDTLS_SSL_ARC4_ENABLED 0
274#define MBEDTLS_SSL_ARC4_DISABLED 1
275
276#define MBEDTLS_SSL_PRESET_DEFAULT 0
277#define MBEDTLS_SSL_PRESET_SUITEB 2
278
279#define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED 1
280#define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 0
281
282#define MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED 0
283#define MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED 1
284
285/*
286 * Default range for DTLS retransmission timer value, in milliseconds.
287 * RFC 6347 4.2.4.1 says from 1 second to 60 seconds.
288 */
289#define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN 1000
290#define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX 60000
291
292/**
293 * \name SECTION: Module settings
294 *
295 * The configuration options you can set for this module are in this section.
296 * Either change them in config.h or define them on the compiler command line.
297 * \{
298 */
299
300#if !defined(MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME)
301#define MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME 86400 /**< Lifetime of session tickets (if enabled) */
302#endif
303
304/*
305 * Maximum fragment length in bytes,
306 * determines the size of each of the two internal I/O buffers.
307 *
308 * Note: the RFC defines the default size of SSL / TLS messages. If you
309 * change the value here, other clients / servers may not be able to
310 * communicate with you anymore. Only change this value if you control
311 * both sides of the connection and have it reduced at both sides, or
312 * if you're using the Max Fragment Length extension and you know all your
313 * peers are using it too!
314 */
315#if !defined(MBEDTLS_SSL_MAX_CONTENT_LEN)
316#define MBEDTLS_SSL_MAX_CONTENT_LEN 16384 /**< Size of the input / output buffer */
317#endif
318
319#if !defined(MBEDTLS_SSL_IN_CONTENT_LEN)
320#define MBEDTLS_SSL_IN_CONTENT_LEN MBEDTLS_SSL_MAX_CONTENT_LEN
321#endif
322
323#if !defined(MBEDTLS_SSL_OUT_CONTENT_LEN)
324#define MBEDTLS_SSL_OUT_CONTENT_LEN MBEDTLS_SSL_MAX_CONTENT_LEN
325#endif
326
327/*
328 * Maximum number of heap-allocated bytes for the purpose of
329 * DTLS handshake message reassembly and future message buffering.
330 */
331#if !defined(MBEDTLS_SSL_DTLS_MAX_BUFFERING)
332#define MBEDTLS_SSL_DTLS_MAX_BUFFERING 32768
333#endif
334
335/*
336 * Maximum length of CIDs for incoming and outgoing messages.
337 */
338#if !defined(MBEDTLS_SSL_CID_IN_LEN_MAX)
339#define MBEDTLS_SSL_CID_IN_LEN_MAX 32
340#endif
341
342#if !defined(MBEDTLS_SSL_CID_OUT_LEN_MAX)
343#define MBEDTLS_SSL_CID_OUT_LEN_MAX 32
344#endif
345
346#if !defined(MBEDTLS_SSL_CID_PADDING_GRANULARITY)
347#define MBEDTLS_SSL_CID_PADDING_GRANULARITY 16
348#endif
349
350#if !defined(MBEDTLS_SSL_TLS1_3_PADDING_GRANULARITY)
351#define MBEDTLS_SSL_TLS1_3_PADDING_GRANULARITY 1
352#endif
353
354/** \} name SECTION: Module settings */
355
356/*
357 * Length of the verify data for secure renegotiation
358 */
359#if defined(MBEDTLS_SSL_PROTO_SSL3)
360#define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 36
361#else
362#define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 12
363#endif
364
365/*
366 * Signaling ciphersuite values (SCSV)
367 */
368#define MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO 0xFF /**< renegotiation info ext */
369#define MBEDTLS_SSL_FALLBACK_SCSV_VALUE 0x5600 /**< RFC 7507 section 2 */
370
371/*
372 * Supported Signature and Hash algorithms (For TLS 1.2)
373 * RFC 5246 section 7.4.1.4.1
374 */
375#define MBEDTLS_SSL_HASH_NONE 0
376#define MBEDTLS_SSL_HASH_MD5 1
377#define MBEDTLS_SSL_HASH_SHA1 2
378#define MBEDTLS_SSL_HASH_SHA224 3
379#define MBEDTLS_SSL_HASH_SHA256 4
380#define MBEDTLS_SSL_HASH_SHA384 5
381#define MBEDTLS_SSL_HASH_SHA512 6
382
383#define MBEDTLS_SSL_SIG_ANON 0
384#define MBEDTLS_SSL_SIG_RSA 1
385#define MBEDTLS_SSL_SIG_ECDSA 3
386
387/*
388 * Client Certificate Types
389 * RFC 5246 section 7.4.4 plus RFC 4492 section 5.5
390 */
391#define MBEDTLS_SSL_CERT_TYPE_RSA_SIGN 1
392#define MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN 64
393
394/*
395 * Message, alert and handshake types
396 */
397#define MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC 20
398#define MBEDTLS_SSL_MSG_ALERT 21
399#define MBEDTLS_SSL_MSG_HANDSHAKE 22
400#define MBEDTLS_SSL_MSG_APPLICATION_DATA 23
401#define MBEDTLS_SSL_MSG_CID 25
402
403#define MBEDTLS_SSL_ALERT_LEVEL_WARNING 1
404#define MBEDTLS_SSL_ALERT_LEVEL_FATAL 2
405
406#define MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY 0 /* 0x00 */
407#define MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE 10 /* 0x0A */
408#define MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC 20 /* 0x14 */
409#define MBEDTLS_SSL_ALERT_MSG_DECRYPTION_FAILED 21 /* 0x15 */
410#define MBEDTLS_SSL_ALERT_MSG_RECORD_OVERFLOW 22 /* 0x16 */
411#define MBEDTLS_SSL_ALERT_MSG_DECOMPRESSION_FAILURE 30 /* 0x1E */
412#define MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE 40 /* 0x28 */
413#define MBEDTLS_SSL_ALERT_MSG_NO_CERT 41 /* 0x29 */
414#define MBEDTLS_SSL_ALERT_MSG_BAD_CERT 42 /* 0x2A */
415#define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT 43 /* 0x2B */
416#define MBEDTLS_SSL_ALERT_MSG_CERT_REVOKED 44 /* 0x2C */
417#define MBEDTLS_SSL_ALERT_MSG_CERT_EXPIRED 45 /* 0x2D */
418#define MBEDTLS_SSL_ALERT_MSG_CERT_UNKNOWN 46 /* 0x2E */
419#define MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER 47 /* 0x2F */
420#define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_CA 48 /* 0x30 */
421#define MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED 49 /* 0x31 */
422#define MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR 50 /* 0x32 */
423#define MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR 51 /* 0x33 */
424#define MBEDTLS_SSL_ALERT_MSG_EXPORT_RESTRICTION 60 /* 0x3C */
425#define MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION 70 /* 0x46 */
426#define MBEDTLS_SSL_ALERT_MSG_INSUFFICIENT_SECURITY 71 /* 0x47 */
427#define MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR 80 /* 0x50 */
428#define MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK 86 /* 0x56 */
429#define MBEDTLS_SSL_ALERT_MSG_USER_CANCELED 90 /* 0x5A */
430#define MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION 100 /* 0x64 */
431#define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT 110 /* 0x6E */
432#define MBEDTLS_SSL_ALERT_MSG_UNRECOGNIZED_NAME 112 /* 0x70 */
433#define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY 115 /* 0x73 */
434#define MBEDTLS_SSL_ALERT_MSG_NO_APPLICATION_PROTOCOL 120 /* 0x78 */
435
436#define MBEDTLS_SSL_HS_HELLO_REQUEST 0
437#define MBEDTLS_SSL_HS_CLIENT_HELLO 1
438#define MBEDTLS_SSL_HS_SERVER_HELLO 2
439#define MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST 3
440#define MBEDTLS_SSL_HS_NEW_SESSION_TICKET 4
441#define MBEDTLS_SSL_HS_CERTIFICATE 11
442#define MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE 12
443#define MBEDTLS_SSL_HS_CERTIFICATE_REQUEST 13
444#define MBEDTLS_SSL_HS_SERVER_HELLO_DONE 14
445#define MBEDTLS_SSL_HS_CERTIFICATE_VERIFY 15
446#define MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE 16
447#define MBEDTLS_SSL_HS_FINISHED 20
448
449/*
450 * TLS extensions
451 */
452#define MBEDTLS_TLS_EXT_SERVERNAME 0
453#define MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME 0
454
455#define MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH 1
456
457#define MBEDTLS_TLS_EXT_TRUNCATED_HMAC 4
458
459#define MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES 10
460#define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS 11
461
462#define MBEDTLS_TLS_EXT_SIG_ALG 13
463
464#define MBEDTLS_TLS_EXT_USE_SRTP 14
465
466#define MBEDTLS_TLS_EXT_ALPN 16
467
468#define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC 22 /* 0x16 */
469#define MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET 0x0017 /* 23 */
470
471#define MBEDTLS_TLS_EXT_SESSION_TICKET 35
472
473/* The value of the CID extension is still TBD as of
474 * draft-ietf-tls-dtls-connection-id-05
475 * (https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05).
476 *
477 * A future minor revision of Mbed TLS may change the default value of
478 * this option to match evolving standards and usage.
479 */
480#if !defined(MBEDTLS_TLS_EXT_CID)
481#define MBEDTLS_TLS_EXT_CID 254 /* TBD */
482#endif
483
484#define MBEDTLS_TLS_EXT_ECJPAKE_KKPP 256 /* experimental */
485
486#define MBEDTLS_TLS_EXT_RENEGOTIATION_INFO 0xFF01
487
488/*
489 * Size defines
490 */
491#if !defined(MBEDTLS_PSK_MAX_LEN)
492#define MBEDTLS_PSK_MAX_LEN 32 /* 256 bits */
493#endif
494
495/* Dummy type used only for its size */
496union mbedtls_ssl_premaster_secret {
497 unsigned char dummy; /* Make the union non-empty even with SSL disabled */
498#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
499 unsigned char _pms_rsa[48]; /* RFC 5246 8.1.1 */
500#endif
501#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)
502 unsigned char _pms_dhm[MBEDTLS_MPI_MAX_SIZE]; /* RFC 5246 8.1.2 */
503#endif
504#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
505 defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
506 defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
507 defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
508 unsigned char _pms_ecdh[MBEDTLS_ECP_MAX_BYTES]; /* RFC 4492 5.10 */
509#endif
510#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
511 unsigned char _pms_psk[4 + 2 * MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 2 */
512#endif
513#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
514 unsigned char _pms_dhe_psk[4 + MBEDTLS_MPI_MAX_SIZE
515 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 3 */
516#endif
517#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
518 unsigned char _pms_rsa_psk[52 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 4 */
519#endif
520#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
521 unsigned char _pms_ecdhe_psk[4 + MBEDTLS_ECP_MAX_BYTES
522 + MBEDTLS_PSK_MAX_LEN]; /* RFC 5489 2 */
523#endif
524#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
525 unsigned char _pms_ecjpake[32]; /* Thread spec: SHA-256 output */
526#endif
527};
528
529#define MBEDTLS_PREMASTER_SIZE sizeof(union mbedtls_ssl_premaster_secret)
530
531#ifdef __cplusplus
532extern "C" {
533#endif
534
535/*
536 * SSL state machine
537 */
538typedef enum {
539 MBEDTLS_SSL_HELLO_REQUEST,
540 MBEDTLS_SSL_CLIENT_HELLO,
541 MBEDTLS_SSL_SERVER_HELLO,
542 MBEDTLS_SSL_SERVER_CERTIFICATE,
543 MBEDTLS_SSL_SERVER_KEY_EXCHANGE,
544 MBEDTLS_SSL_CERTIFICATE_REQUEST,
545 MBEDTLS_SSL_SERVER_HELLO_DONE,
546 MBEDTLS_SSL_CLIENT_CERTIFICATE,
547 MBEDTLS_SSL_CLIENT_KEY_EXCHANGE,
548 MBEDTLS_SSL_CERTIFICATE_VERIFY,
549 MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC,
550 MBEDTLS_SSL_CLIENT_FINISHED,
551 MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC,
552 MBEDTLS_SSL_SERVER_FINISHED,
553 MBEDTLS_SSL_FLUSH_BUFFERS,
554 MBEDTLS_SSL_HANDSHAKE_WRAPUP,
555 MBEDTLS_SSL_HANDSHAKE_OVER,
556 MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET,
557 MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT,
558}
559mbedtls_ssl_states;
560
561/*
562 * The tls_prf function types.
563 */
564typedef enum {
565 MBEDTLS_SSL_TLS_PRF_NONE,
566 MBEDTLS_SSL_TLS_PRF_SSL3,
567 MBEDTLS_SSL_TLS_PRF_TLS1,
568 MBEDTLS_SSL_TLS_PRF_SHA384,
569 MBEDTLS_SSL_TLS_PRF_SHA256
570}
571mbedtls_tls_prf_types;
572/**
573 * \brief Callback type: send data on the network.
574 *
575 * \note That callback may be either blocking or non-blocking.
576 *
577 * \param ctx Context for the send callback (typically a file descriptor)
578 * \param buf Buffer holding the data to send
579 * \param len Length of the data to send
580 *
581 * \return The callback must return the number of bytes sent if any,
582 * or a non-zero error code.
583 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_WRITE
584 * must be returned when the operation would block.
585 *
586 * \note The callback is allowed to send fewer bytes than requested.
587 * It must always return the number of bytes actually sent.
588 */
589typedef int mbedtls_ssl_send_t(void *ctx,
590 const unsigned char *buf,
591 size_t len);
592
593/**
594 * \brief Callback type: receive data from the network.
595 *
596 * \note That callback may be either blocking or non-blocking.
597 *
598 * \param ctx Context for the receive callback (typically a file
599 * descriptor)
600 * \param buf Buffer to write the received data to
601 * \param len Length of the receive buffer
602 *
603 * \returns If data has been received, the positive number of bytes received.
604 * \returns \c 0 if the connection has been closed.
605 * \returns If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ
606 * must be returned when the operation would block.
607 * \returns Another negative error code on other kinds of failures.
608 *
609 * \note The callback may receive fewer bytes than the length of the
610 * buffer. It must always return the number of bytes actually
611 * received and written to the buffer.
612 */
613typedef int mbedtls_ssl_recv_t(void *ctx,
614 unsigned char *buf,
615 size_t len);
616
617/**
618 * \brief Callback type: receive data from the network, with timeout
619 *
620 * \note That callback must block until data is received, or the
621 * timeout delay expires, or the operation is interrupted by a
622 * signal.
623 *
624 * \param ctx Context for the receive callback (typically a file descriptor)
625 * \param buf Buffer to write the received data to
626 * \param len Length of the receive buffer
627 * \param timeout Maximum number of milliseconds to wait for data
628 * 0 means no timeout (potentially waiting forever)
629 *
630 * \return The callback must return the number of bytes received,
631 * or a non-zero error code:
632 * \c MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out,
633 * \c MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal.
634 *
635 * \note The callback may receive fewer bytes than the length of the
636 * buffer. It must always return the number of bytes actually
637 * received and written to the buffer.
638 */
639typedef int mbedtls_ssl_recv_timeout_t(void *ctx,
640 unsigned char *buf,
641 size_t len,
642 uint32_t timeout);
643/**
644 * \brief Callback type: set a pair of timers/delays to watch
645 *
646 * \param ctx Context pointer
647 * \param int_ms Intermediate delay in milliseconds
648 * \param fin_ms Final delay in milliseconds
649 * 0 cancels the current timer.
650 *
651 * \note This callback must at least store the necessary information
652 * for the associated \c mbedtls_ssl_get_timer_t callback to
653 * return correct information.
654 *
655 * \note If using an event-driven style of programming, an event must
656 * be generated when the final delay is passed. The event must
657 * cause a call to \c mbedtls_ssl_handshake() with the proper
658 * SSL context to be scheduled. Care must be taken to ensure
659 * that at most one such call happens at a time.
660 *
661 * \note Only one timer at a time must be running. Calling this
662 * function while a timer is running must cancel it. Cancelled
663 * timers must not generate any event.
664 */
665typedef void mbedtls_ssl_set_timer_t(void *ctx,
666 uint32_t int_ms,
667 uint32_t fin_ms);
668
669/**
670 * \brief Callback type: get status of timers/delays
671 *
672 * \param ctx Context pointer
673 *
674 * \return This callback must return:
675 * -1 if cancelled (fin_ms == 0),
676 * 0 if none of the delays have passed,
677 * 1 if only the intermediate delay has passed,
678 * 2 if the final delay has passed.
679 */
680typedef int mbedtls_ssl_get_timer_t(void *ctx);
681
682/* Defined below */
683typedef struct mbedtls_ssl_session mbedtls_ssl_session;
684typedef struct mbedtls_ssl_context mbedtls_ssl_context;
685typedef struct mbedtls_ssl_config mbedtls_ssl_config;
686
687/* Defined in ssl_internal.h */
688typedef struct mbedtls_ssl_transform mbedtls_ssl_transform;
689typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params;
690typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t;
691#if defined(MBEDTLS_X509_CRT_PARSE_C)
692typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert;
693#endif
694#if defined(MBEDTLS_SSL_PROTO_DTLS)
695typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item;
696#endif
697
698#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
699#if defined(MBEDTLS_X509_CRT_PARSE_C)
700/**
701 * \brief Callback type: start external signature operation.
702 *
703 * This callback is called during an SSL handshake to start
704 * a signature decryption operation using an
705 * external processor. The parameter \p cert contains
706 * the public key; it is up to the callback function to
707 * determine how to access the associated private key.
708 *
709 * This function typically sends or enqueues a request, and
710 * does not wait for the operation to complete. This allows
711 * the handshake step to be non-blocking.
712 *
713 * The parameters \p ssl and \p cert are guaranteed to remain
714 * valid throughout the handshake. On the other hand, this
715 * function must save the contents of \p hash if the value
716 * is needed for later processing, because the \p hash buffer
717 * is no longer valid after this function returns.
718 *
719 * This function may call mbedtls_ssl_set_async_operation_data()
720 * to store an operation context for later retrieval
721 * by the resume or cancel callback.
722 *
723 * \note For RSA signatures, this function must produce output
724 * that is consistent with PKCS#1 v1.5 in the same way as
725 * mbedtls_rsa_pkcs1_sign(). Before the private key operation,
726 * apply the padding steps described in RFC 8017, section 9.2
727 * "EMSA-PKCS1-v1_5" as follows.
728 * - If \p md_alg is #MBEDTLS_MD_NONE, apply the PKCS#1 v1.5
729 * encoding, treating \p hash as the DigestInfo to be
730 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
731 * from step 3, with `T = hash` and `tLen = hash_len`.
732 * - If `md_alg != MBEDTLS_MD_NONE`, apply the PKCS#1 v1.5
733 * encoding, treating \p hash as the hash to be encoded and
734 * padded. In other words, apply EMSA-PKCS1-v1_5 starting
735 * from step 2, with `digestAlgorithm` obtained by calling
736 * mbedtls_oid_get_oid_by_md() on \p md_alg.
737 *
738 * \note For ECDSA signatures, the output format is the DER encoding
739 * `Ecdsa-Sig-Value` defined in
740 * [RFC 4492 section 5.4](https://tools.ietf.org/html/rfc4492#section-5.4).
741 *
742 * \param ssl The SSL connection instance. It should not be
743 * modified other than via
744 * mbedtls_ssl_set_async_operation_data().
745 * \param cert Certificate containing the public key.
746 * In simple cases, this is one of the pointers passed to
747 * mbedtls_ssl_conf_own_cert() when configuring the SSL
748 * connection. However, if other callbacks are used, this
749 * property may not hold. For example, if an SNI callback
750 * is registered with mbedtls_ssl_conf_sni(), then
751 * this callback determines what certificate is used.
752 * \param md_alg Hash algorithm.
753 * \param hash Buffer containing the hash. This buffer is
754 * no longer valid when the function returns.
755 * \param hash_len Size of the \c hash buffer in bytes.
756 *
757 * \return 0 if the operation was started successfully and the SSL
758 * stack should call the resume callback immediately.
759 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
760 * was started successfully and the SSL stack should return
761 * immediately without calling the resume callback yet.
762 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
763 * processor does not support this key. The SSL stack will
764 * use the private key object instead.
765 * \return Any other error indicates a fatal failure and is
766 * propagated up the call chain. The callback should
767 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
768 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
769 * directed in the documentation of this callback.
770 */
771typedef int mbedtls_ssl_async_sign_t(mbedtls_ssl_context *ssl,
772 mbedtls_x509_crt *cert,
773 mbedtls_md_type_t md_alg,
774 const unsigned char *hash,
775 size_t hash_len);
776
777/**
778 * \brief Callback type: start external decryption operation.
779 *
780 * This callback is called during an SSL handshake to start
781 * an RSA decryption operation using an
782 * external processor. The parameter \p cert contains
783 * the public key; it is up to the callback function to
784 * determine how to access the associated private key.
785 *
786 * This function typically sends or enqueues a request, and
787 * does not wait for the operation to complete. This allows
788 * the handshake step to be non-blocking.
789 *
790 * The parameters \p ssl and \p cert are guaranteed to remain
791 * valid throughout the handshake. On the other hand, this
792 * function must save the contents of \p input if the value
793 * is needed for later processing, because the \p input buffer
794 * is no longer valid after this function returns.
795 *
796 * This function may call mbedtls_ssl_set_async_operation_data()
797 * to store an operation context for later retrieval
798 * by the resume or cancel callback.
799 *
800 * \warning RSA decryption as used in TLS is subject to a potential
801 * timing side channel attack first discovered by Bleichenbacher
802 * in 1998. This attack can be remotely exploitable
803 * in practice. To avoid this attack, you must ensure that
804 * if the callback performs an RSA decryption, the time it
805 * takes to execute and return the result does not depend
806 * on whether the RSA decryption succeeded or reported
807 * invalid padding.
808 *
809 * \param ssl The SSL connection instance. It should not be
810 * modified other than via
811 * mbedtls_ssl_set_async_operation_data().
812 * \param cert Certificate containing the public key.
813 * In simple cases, this is one of the pointers passed to
814 * mbedtls_ssl_conf_own_cert() when configuring the SSL
815 * connection. However, if other callbacks are used, this
816 * property may not hold. For example, if an SNI callback
817 * is registered with mbedtls_ssl_conf_sni(), then
818 * this callback determines what certificate is used.
819 * \param input Buffer containing the input ciphertext. This buffer
820 * is no longer valid when the function returns.
821 * \param input_len Size of the \p input buffer in bytes.
822 *
823 * \return 0 if the operation was started successfully and the SSL
824 * stack should call the resume callback immediately.
825 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
826 * was started successfully and the SSL stack should return
827 * immediately without calling the resume callback yet.
828 * \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
829 * processor does not support this key. The SSL stack will
830 * use the private key object instead.
831 * \return Any other error indicates a fatal failure and is
832 * propagated up the call chain. The callback should
833 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
834 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
835 * directed in the documentation of this callback.
836 */
837typedef int mbedtls_ssl_async_decrypt_t(mbedtls_ssl_context *ssl,
838 mbedtls_x509_crt *cert,
839 const unsigned char *input,
840 size_t input_len);
841#endif /* MBEDTLS_X509_CRT_PARSE_C */
842
843/**
844 * \brief Callback type: resume external operation.
845 *
846 * This callback is called during an SSL handshake to resume
847 * an external operation started by the
848 * ::mbedtls_ssl_async_sign_t or
849 * ::mbedtls_ssl_async_decrypt_t callback.
850 *
851 * This function typically checks the status of a pending
852 * request or causes the request queue to make progress, and
853 * does not wait for the operation to complete. This allows
854 * the handshake step to be non-blocking.
855 *
856 * This function may call mbedtls_ssl_get_async_operation_data()
857 * to retrieve an operation context set by the start callback.
858 * It may call mbedtls_ssl_set_async_operation_data() to modify
859 * this context.
860 *
861 * Note that when this function returns a status other than
862 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, it must free any
863 * resources associated with the operation.
864 *
865 * \param ssl The SSL connection instance. It should not be
866 * modified other than via
867 * mbedtls_ssl_set_async_operation_data().
868 * \param output Buffer containing the output (signature or decrypted
869 * data) on success.
870 * \param output_len On success, number of bytes written to \p output.
871 * \param output_size Size of the \p output buffer in bytes.
872 *
873 * \return 0 if output of the operation is available in the
874 * \p output buffer.
875 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
876 * is still in progress. Subsequent requests for progress
877 * on the SSL connection will call the resume callback
878 * again.
879 * \return Any other error means that the operation is aborted.
880 * The SSL handshake is aborted. The callback should
881 * use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
882 * use \c MBEDTLS_ERR_SSL_xxx error codes except as
883 * directed in the documentation of this callback.
884 */
885typedef int mbedtls_ssl_async_resume_t(mbedtls_ssl_context *ssl,
886 unsigned char *output,
887 size_t *output_len,
888 size_t output_size);
889
890/**
891 * \brief Callback type: cancel external operation.
892 *
893 * This callback is called if an SSL connection is closed
894 * while an asynchronous operation is in progress. Note that
895 * this callback is not called if the
896 * ::mbedtls_ssl_async_resume_t callback has run and has
897 * returned a value other than
898 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, since in that case
899 * the asynchronous operation has already completed.
900 *
901 * This function may call mbedtls_ssl_get_async_operation_data()
902 * to retrieve an operation context set by the start callback.
903 *
904 * \param ssl The SSL connection instance. It should not be
905 * modified.
906 */
907typedef void mbedtls_ssl_async_cancel_t(mbedtls_ssl_context *ssl);
908#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
909
910#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) && \
911 !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
912#define MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN 48
913#if defined(MBEDTLS_SHA256_C)
914#define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA256
915#define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 32
916#elif defined(MBEDTLS_SHA512_C)
917#define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA384
918#define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 48
919#elif defined(MBEDTLS_SHA1_C)
920#define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA1
921#define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN 20
922#else
923/* This is already checked in check_config.h, but be sure. */
924#error "Bad configuration - need SHA-1, SHA-256 or SHA-512 enabled to compute digest of peer CRT."
925#endif
926#endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED &&
927 !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
928
929#if defined(MBEDTLS_SSL_DTLS_SRTP)
930
931#define MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH 255
932#define MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH 4
933/*
934 * For code readability use a typedef for DTLS-SRTP profiles
935 *
936 * Use_srtp extension protection profiles values as defined in
937 * http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
938 *
939 * Reminder: if this list is expanded mbedtls_ssl_check_srtp_profile_value
940 * must be updated too.
941 */
942#define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80 ((uint16_t) 0x0001)
943#define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32 ((uint16_t) 0x0002)
944#define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80 ((uint16_t) 0x0005)
945#define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32 ((uint16_t) 0x0006)
946/* This one is not iana defined, but for code readability. */
947#define MBEDTLS_TLS_SRTP_UNSET ((uint16_t) 0x0000)
948
949typedef uint16_t mbedtls_ssl_srtp_profile;
950
951typedef struct mbedtls_dtls_srtp_info_t {
952 /*! The SRTP profile that was negotiated. */
953 mbedtls_ssl_srtp_profile chosen_dtls_srtp_profile;
954 /*! The length of mki_value. */
955 uint16_t mki_len;
956 /*! The mki_value used, with max size of 256 bytes. */
957 unsigned char mki_value[MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH];
958}
959mbedtls_dtls_srtp_info;
960
961#endif /* MBEDTLS_SSL_DTLS_SRTP */
962
963/*
964 * This structure is used for storing current session data.
965 *
966 * Note: when changing this definition, we need to check and update:
967 * - in tests/suites/test_suite_ssl.function:
968 * ssl_populate_session() and ssl_serialize_session_save_load()
969 * - in library/ssl_tls.c:
970 * mbedtls_ssl_session_init() and mbedtls_ssl_session_free()
971 * mbedtls_ssl_session_save() and ssl_session_load()
972 * ssl_session_copy()
973 */
974struct mbedtls_ssl_session {
975#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
976 unsigned char mfl_code; /*!< MaxFragmentLength negotiated by peer */
977#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
978
979#if defined(MBEDTLS_HAVE_TIME)
980 mbedtls_time_t start; /*!< starting time */
981#endif
982 int ciphersuite; /*!< chosen ciphersuite */
983 int compression; /*!< chosen compression */
984 size_t id_len; /*!< session id length */
985 unsigned char id[32]; /*!< session identifier */
986 unsigned char master[48]; /*!< the master secret */
987
988#if defined(MBEDTLS_X509_CRT_PARSE_C)
989#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
990 mbedtls_x509_crt *peer_cert; /*!< peer X.509 cert chain */
991#else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
992 /*! The digest of the peer's end-CRT. This must be kept to detect CRT
993 * changes during renegotiation, mitigating the triple handshake attack. */
994 unsigned char *peer_cert_digest;
995 size_t peer_cert_digest_len;
996 mbedtls_md_type_t peer_cert_digest_type;
997#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
998#endif /* MBEDTLS_X509_CRT_PARSE_C */
999 uint32_t verify_result; /*!< verification result */
1000
1001#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
1002 unsigned char *ticket; /*!< RFC 5077 session ticket */
1003 size_t ticket_len; /*!< session ticket length */
1004 uint32_t ticket_lifetime; /*!< ticket lifetime hint */
1005#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
1006
1007#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
1008 int trunc_hmac; /*!< flag for truncated hmac activation */
1009#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
1010
1011#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1012 int encrypt_then_mac; /*!< flag for EtM activation */
1013#endif
1014};
1015
1016/**
1017 * SSL/TLS configuration to be shared between mbedtls_ssl_context structures.
1018 */
1019struct mbedtls_ssl_config {
1020 /* Group items by size and reorder them to maximize usage of immediate offset access. */
1021
1022 /*
1023 * Numerical settings (char)
1024 */
1025
1026 unsigned char max_major_ver; /*!< max. major version used */
1027 unsigned char max_minor_ver; /*!< max. minor version used */
1028 unsigned char min_major_ver; /*!< min. major version used */
1029 unsigned char min_minor_ver; /*!< min. minor version used */
1030
1031 /*
1032 * Flags (could be bit-fields to save RAM, but separate bytes make
1033 * the code smaller on architectures with an instruction for direct
1034 * byte access).
1035 */
1036
1037 uint8_t endpoint /*bool*/; /*!< 0: client, 1: server */
1038 uint8_t transport /*bool*/; /*!< stream (TLS) or datagram (DTLS) */
1039 uint8_t authmode /*2 bits*/; /*!< MBEDTLS_SSL_VERIFY_XXX */
1040 /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE */
1041 uint8_t allow_legacy_renegotiation /*2 bits*/; /*!< MBEDTLS_LEGACY_XXX */
1042#if defined(MBEDTLS_ARC4_C)
1043 uint8_t arc4_disabled /*bool*/; /*!< blacklist RC4 ciphersuites? */
1044#endif
1045#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
1046 uint8_t mfl_code /*3 bits*/; /*!< desired fragment length */
1047#endif
1048#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1049 uint8_t encrypt_then_mac /*bool*/; /*!< negotiate encrypt-then-mac? */
1050#endif
1051#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
1052 uint8_t extended_ms /*bool*/; /*!< negotiate extended master secret? */
1053#endif
1054#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1055 uint8_t anti_replay /*bool*/; /*!< detect and prevent replay? */
1056#endif
1057#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
1058 uint8_t cbc_record_splitting /*bool*/; /*!< do cbc record splitting */
1059#endif
1060#if defined(MBEDTLS_SSL_RENEGOTIATION)
1061 uint8_t disable_renegotiation /*bool*/; /*!< disable renegotiation? */
1062#endif
1063#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
1064 uint8_t trunc_hmac /*bool*/; /*!< negotiate truncated hmac? */
1065#endif
1066#if defined(MBEDTLS_SSL_SESSION_TICKETS)
1067 uint8_t session_tickets /*bool*/; /*!< use session tickets? */
1068#endif
1069#if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C)
1070 uint8_t fallback /*bool*/; /*!< is this a fallback? */
1071#endif
1072#if defined(MBEDTLS_SSL_SRV_C)
1073 uint8_t cert_req_ca_list /*bool*/; /*!< enable sending CA list in
1074 Certificate Request messages? */
1075#endif
1076#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1077 uint8_t ignore_unexpected_cid /*bool*/; /*!< Determines whether DTLS
1078 * record with unexpected CID
1079 * should lead to failure. */
1080#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1081#if defined(MBEDTLS_SSL_DTLS_SRTP)
1082 uint8_t dtls_srtp_mki_support /*bool*/; /*!< support having mki_value
1083 in the use_srtp extension? */
1084#endif
1085
1086 /*
1087 * Numerical settings (int or larger)
1088 */
1089
1090 uint32_t read_timeout; /*!< timeout for mbedtls_ssl_read (ms) */
1091
1092#if defined(MBEDTLS_SSL_PROTO_DTLS)
1093 uint32_t hs_timeout_min; /*!< initial value of the handshake
1094 retransmission timeout (ms) */
1095 uint32_t hs_timeout_max; /*!< maximum value of the handshake
1096 retransmission timeout (ms) */
1097#endif
1098
1099#if defined(MBEDTLS_SSL_RENEGOTIATION)
1100 int renego_max_records; /*!< grace period for renegotiation */
1101 unsigned char renego_period[8]; /*!< value of the record counters
1102 that triggers renegotiation */
1103#endif
1104
1105#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
1106 unsigned int badmac_limit; /*!< limit of records with a bad MAC */
1107#endif
1108
1109#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
1110 unsigned int dhm_min_bitlen; /*!< min. bit length of the DHM prime */
1111#endif
1112
1113 /*
1114 * Pointers
1115 */
1116
1117 const int *ciphersuite_list[4]; /*!< allowed ciphersuites per version */
1118
1119 /** Callback for printing debug output */
1120 void (*f_dbg)(void *, int, const char *, int, const char *);
1121 void *p_dbg; /*!< context for the debug function */
1122
1123 /** Callback for getting (pseudo-)random numbers */
1124 int (*f_rng)(void *, unsigned char *, size_t);
1125 void *p_rng; /*!< context for the RNG function */
1126
1127 /** Callback to retrieve a session from the cache */
1128 int (*f_get_cache)(void *, mbedtls_ssl_session *);
1129 /** Callback to store a session into the cache */
1130 int (*f_set_cache)(void *, const mbedtls_ssl_session *);
1131 void *p_cache; /*!< context for cache callbacks */
1132
1133#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
1134 /** Callback for setting cert according to SNI extension */
1135 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
1136 void *p_sni; /*!< context for SNI callback */
1137#endif
1138
1139#if defined(MBEDTLS_X509_CRT_PARSE_C)
1140 /** Callback to customize X.509 certificate chain verification */
1141 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *);
1142 void *p_vrfy; /*!< context for X.509 verify calllback */
1143#endif
1144
1145#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
1146 /** Callback to retrieve PSK key from identity */
1147 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
1148 void *p_psk; /*!< context for PSK callback */
1149#endif
1150
1151#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1152 /** Callback to create & write a cookie for ClientHello verification */
1153 int (*f_cookie_write)(void *, unsigned char **, unsigned char *,
1154 const unsigned char *, size_t);
1155 /** Callback to verify validity of a ClientHello cookie */
1156 int (*f_cookie_check)(void *, const unsigned char *, size_t,
1157 const unsigned char *, size_t);
1158 void *p_cookie; /*!< context for the cookie callbacks */
1159#endif
1160
1161#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
1162 /** Callback to create & write a session ticket */
1163 int (*f_ticket_write)(void *, const mbedtls_ssl_session *,
1164 unsigned char *, const unsigned char *, size_t *, uint32_t *);
1165 /** Callback to parse a session ticket into a session structure */
1166 int (*f_ticket_parse)(void *, mbedtls_ssl_session *, unsigned char *, size_t);
1167 void *p_ticket; /*!< context for the ticket callbacks */
1168#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
1169
1170#if defined(MBEDTLS_SSL_EXPORT_KEYS)
1171 /** Callback to export key block and master secret */
1172 int (*f_export_keys)(void *, const unsigned char *,
1173 const unsigned char *, size_t, size_t, size_t);
1174 /** Callback to export key block, master secret,
1175 * tls_prf and random bytes. Should replace f_export_keys */
1176 int (*f_export_keys_ext)(void *, const unsigned char *,
1177 const unsigned char *, size_t, size_t, size_t,
1178 const unsigned char[32], const unsigned char[32],
1179 mbedtls_tls_prf_types);
1180 void *p_export_keys; /*!< context for key export callback */
1181#endif
1182
1183#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1184 size_t cid_len; /*!< The length of CIDs for incoming DTLS records. */
1185#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1186
1187#if defined(MBEDTLS_X509_CRT_PARSE_C)
1188 const mbedtls_x509_crt_profile *cert_profile; /*!< verification profile */
1189 mbedtls_ssl_key_cert *key_cert; /*!< own certificate/key pair(s) */
1190 mbedtls_x509_crt *ca_chain; /*!< trusted CAs */
1191 mbedtls_x509_crl *ca_crl; /*!< trusted CAs CRLs */
1192#if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
1193 mbedtls_x509_crt_ca_cb_t f_ca_cb;
1194 void *p_ca_cb;
1195#endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
1196#endif /* MBEDTLS_X509_CRT_PARSE_C */
1197
1198#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
1199#if defined(MBEDTLS_X509_CRT_PARSE_C)
1200 mbedtls_ssl_async_sign_t *f_async_sign_start; /*!< start asynchronous signature operation */
1201 mbedtls_ssl_async_decrypt_t *f_async_decrypt_start; /*!< start asynchronous decryption operation */
1202#endif /* MBEDTLS_X509_CRT_PARSE_C */
1203 mbedtls_ssl_async_resume_t *f_async_resume; /*!< resume asynchronous operation */
1204 mbedtls_ssl_async_cancel_t *f_async_cancel; /*!< cancel asynchronous operation */
1205 void *p_async_config_data; /*!< Configuration data set by mbedtls_ssl_conf_async_private_cb(). */
1206#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1207
1208#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
1209 const int *sig_hashes; /*!< allowed signature hashes */
1210#endif
1211
1212#if defined(MBEDTLS_ECP_C)
1213 const mbedtls_ecp_group_id *curve_list; /*!< allowed curves */
1214#endif
1215
1216#if defined(MBEDTLS_DHM_C)
1217 mbedtls_mpi dhm_P; /*!< prime modulus for DHM */
1218 mbedtls_mpi dhm_G; /*!< generator for DHM */
1219#endif
1220
1221#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
1222
1223#if defined(MBEDTLS_USE_PSA_CRYPTO)
1224 psa_key_id_t psk_opaque; /*!< PSA key slot holding opaque PSK. This field
1225 * should only be set via
1226 * mbedtls_ssl_conf_psk_opaque().
1227 * If either no PSK or a raw PSK have been
1228 * configured, this has value \c 0.
1229 */
1230#endif /* MBEDTLS_USE_PSA_CRYPTO */
1231
1232 unsigned char *psk; /*!< The raw pre-shared key. This field should
1233 * only be set via mbedtls_ssl_conf_psk().
1234 * If either no PSK or an opaque PSK
1235 * have been configured, this has value NULL. */
1236 size_t psk_len; /*!< The length of the raw pre-shared key.
1237 * This field should only be set via
1238 * mbedtls_ssl_conf_psk().
1239 * Its value is non-zero if and only if
1240 * \c psk is not \c NULL. */
1241
1242 unsigned char *psk_identity; /*!< The PSK identity for PSK negotiation.
1243 * This field should only be set via
1244 * mbedtls_ssl_conf_psk().
1245 * This is set if and only if either
1246 * \c psk or \c psk_opaque are set. */
1247 size_t psk_identity_len;/*!< The length of PSK identity.
1248 * This field should only be set via
1249 * mbedtls_ssl_conf_psk().
1250 * Its value is non-zero if and only if
1251 * \c psk is not \c NULL or \c psk_opaque
1252 * is not \c 0. */
1253#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
1254
1255#if defined(MBEDTLS_SSL_ALPN)
1256 const char **alpn_list; /*!< ordered list of protocols */
1257#endif
1258
1259#if defined(MBEDTLS_SSL_DTLS_SRTP)
1260 /*! ordered list of supported srtp profile */
1261 const mbedtls_ssl_srtp_profile *dtls_srtp_profile_list;
1262 /*! number of supported profiles */
1263 size_t dtls_srtp_profile_list_len;
1264#endif /* MBEDTLS_SSL_DTLS_SRTP */
1265};
1266
1267struct mbedtls_ssl_context {
1268 const mbedtls_ssl_config *conf; /*!< configuration information */
1269
1270 /*
1271 * Miscellaneous
1272 */
1273 int state; /*!< SSL handshake: current state */
1274#if defined(MBEDTLS_SSL_RENEGOTIATION)
1275 int renego_status; /*!< Initial, in progress, pending? */
1276 int renego_records_seen; /*!< Records since renego request, or with DTLS,
1277 number of retransmissions of request if
1278 renego_max_records is < 0 */
1279#endif /* MBEDTLS_SSL_RENEGOTIATION */
1280
1281 int major_ver; /*!< equal to MBEDTLS_SSL_MAJOR_VERSION_3 */
1282 int minor_ver; /*!< either 0 (SSL3) or 1 (TLS1.0) */
1283
1284#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
1285 unsigned badmac_seen; /*!< records with a bad MAC received */
1286#endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */
1287
1288#if defined(MBEDTLS_X509_CRT_PARSE_C)
1289 /** Callback to customize X.509 certificate chain verification */
1290 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *);
1291 void *p_vrfy; /*!< context for X.509 verify callback */
1292#endif
1293
1294 mbedtls_ssl_send_t *f_send; /*!< Callback for network send */
1295 mbedtls_ssl_recv_t *f_recv; /*!< Callback for network receive */
1296 mbedtls_ssl_recv_timeout_t *f_recv_timeout;
1297 /*!< Callback for network receive with timeout */
1298
1299 void *p_bio; /*!< context for I/O operations */
1300
1301 /*
1302 * Session layer
1303 */
1304 mbedtls_ssl_session *session_in; /*!< current session data (in) */
1305 mbedtls_ssl_session *session_out; /*!< current session data (out) */
1306 mbedtls_ssl_session *session; /*!< negotiated session data */
1307 mbedtls_ssl_session *session_negotiate; /*!< session data in negotiation */
1308
1309 mbedtls_ssl_handshake_params *handshake; /*!< params required only during
1310 the handshake process */
1311
1312 /*
1313 * Record layer transformations
1314 */
1315 mbedtls_ssl_transform *transform_in; /*!< current transform params (in) */
1316 mbedtls_ssl_transform *transform_out; /*!< current transform params (in) */
1317 mbedtls_ssl_transform *transform; /*!< negotiated transform params */
1318 mbedtls_ssl_transform *transform_negotiate; /*!< transform params in negotiation */
1319
1320 /*
1321 * Timers
1322 */
1323 void *p_timer; /*!< context for the timer callbacks */
1324
1325 mbedtls_ssl_set_timer_t *f_set_timer; /*!< set timer callback */
1326 mbedtls_ssl_get_timer_t *f_get_timer; /*!< get timer callback */
1327
1328 /*
1329 * Record layer (incoming data)
1330 */
1331 unsigned char *in_buf; /*!< input buffer */
1332 unsigned char *in_ctr; /*!< 64-bit incoming message counter
1333 TLS: maintained by us
1334 DTLS: read from peer */
1335 unsigned char *in_hdr; /*!< start of record header */
1336#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1337 unsigned char *in_cid; /*!< The start of the CID;
1338 * (the end is marked by in_len). */
1339#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1340 unsigned char *in_len; /*!< two-bytes message length field */
1341 unsigned char *in_iv; /*!< ivlen-byte IV */
1342 unsigned char *in_msg; /*!< message contents (in_iv+ivlen) */
1343 unsigned char *in_offt; /*!< read offset in application data */
1344
1345 int in_msgtype; /*!< record header: message type */
1346 size_t in_msglen; /*!< record header: message length */
1347 size_t in_left; /*!< amount of data read so far */
1348#if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1349 size_t in_buf_len; /*!< length of input buffer */
1350#endif
1351#if defined(MBEDTLS_SSL_PROTO_DTLS)
1352 uint16_t in_epoch; /*!< DTLS epoch for incoming records */
1353 size_t next_record_offset; /*!< offset of the next record in datagram
1354 (equal to in_left if none) */
1355#endif /* MBEDTLS_SSL_PROTO_DTLS */
1356#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1357 uint64_t in_window_top; /*!< last validated record seq_num */
1358 uint64_t in_window; /*!< bitmask for replay detection */
1359#endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
1360
1361 size_t in_hslen; /*!< current handshake message length,
1362 including the handshake header */
1363 int nb_zero; /*!< # of 0-length encrypted messages */
1364
1365 int keep_current_message; /*!< drop or reuse current message
1366 on next call to record layer? */
1367
1368#if defined(MBEDTLS_SSL_PROTO_DTLS)
1369 uint8_t disable_datagram_packing; /*!< Disable packing multiple records
1370 * within a single datagram. */
1371#endif /* MBEDTLS_SSL_PROTO_DTLS */
1372
1373 /*
1374 * Record layer (outgoing data)
1375 */
1376 unsigned char *out_buf; /*!< output buffer */
1377 unsigned char *out_ctr; /*!< 64-bit outgoing message counter */
1378 unsigned char *out_hdr; /*!< start of record header */
1379#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1380 unsigned char *out_cid; /*!< The start of the CID;
1381 * (the end is marked by in_len). */
1382#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1383 unsigned char *out_len; /*!< two-bytes message length field */
1384 unsigned char *out_iv; /*!< ivlen-byte IV */
1385 unsigned char *out_msg; /*!< message contents (out_iv+ivlen) */
1386
1387 int out_msgtype; /*!< record header: message type */
1388 size_t out_msglen; /*!< record header: message length */
1389 size_t out_left; /*!< amount of data not yet written */
1390#if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
1391 size_t out_buf_len; /*!< length of output buffer */
1392#endif
1393
1394 unsigned char cur_out_ctr[8]; /*!< Outgoing record sequence number. */
1395
1396#if defined(MBEDTLS_SSL_PROTO_DTLS)
1397 uint16_t mtu; /*!< path mtu, used to fragment outgoing messages */
1398#endif /* MBEDTLS_SSL_PROTO_DTLS */
1399
1400#if defined(MBEDTLS_ZLIB_SUPPORT)
1401 unsigned char *compress_buf; /*!< zlib data buffer */
1402#endif /* MBEDTLS_ZLIB_SUPPORT */
1403#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
1404 signed char split_done; /*!< current record already split? */
1405#endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */
1406
1407 /*
1408 * PKI layer
1409 */
1410 int client_auth; /*!< flag for client auth. */
1411
1412 /*
1413 * User settings
1414 */
1415#if defined(MBEDTLS_X509_CRT_PARSE_C)
1416 char *hostname; /*!< expected peer CN for verification
1417 (and SNI if available) */
1418#endif /* MBEDTLS_X509_CRT_PARSE_C */
1419
1420#if defined(MBEDTLS_SSL_ALPN)
1421 const char *alpn_chosen; /*!< negotiated protocol */
1422#endif /* MBEDTLS_SSL_ALPN */
1423
1424#if defined(MBEDTLS_SSL_DTLS_SRTP)
1425 /*
1426 * use_srtp extension
1427 */
1428 mbedtls_dtls_srtp_info dtls_srtp_info;
1429#endif /* MBEDTLS_SSL_DTLS_SRTP */
1430
1431 /*
1432 * Information for DTLS hello verify
1433 */
1434#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
1435 unsigned char *cli_id; /*!< transport-level ID of the client */
1436 size_t cli_id_len; /*!< length of cli_id */
1437#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
1438
1439 /*
1440 * Secure renegotiation
1441 */
1442 /* needed to know when to send extension on server */
1443 int secure_renegotiation; /*!< does peer support legacy or
1444 secure renegotiation */
1445#if defined(MBEDTLS_SSL_RENEGOTIATION)
1446 size_t verify_data_len; /*!< length of verify data stored */
1447 char own_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
1448 char peer_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
1449#endif /* MBEDTLS_SSL_RENEGOTIATION */
1450
1451#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1452 /* CID configuration to use in subsequent handshakes. */
1453
1454 /*! The next incoming CID, chosen by the user and applying to
1455 * all subsequent handshakes. This may be different from the
1456 * CID currently used in case the user has re-configured the CID
1457 * after an initial handshake. */
1458 unsigned char own_cid[MBEDTLS_SSL_CID_IN_LEN_MAX];
1459 uint8_t own_cid_len; /*!< The length of \c own_cid. */
1460 uint8_t negotiate_cid; /*!< This indicates whether the CID extension should
1461 * be negotiated in the next handshake or not.
1462 * Possible values are #MBEDTLS_SSL_CID_ENABLED
1463 * and #MBEDTLS_SSL_CID_DISABLED. */
1464#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1465};
1466
1467#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
1468
1469#if !defined(MBEDTLS_DEPRECATED_REMOVED)
1470
1471#define MBEDTLS_SSL_CHANNEL_OUTBOUND MBEDTLS_DEPRECATED_NUMERIC_CONSTANT(0)
1472#define MBEDTLS_SSL_CHANNEL_INBOUND MBEDTLS_DEPRECATED_NUMERIC_CONSTANT(1)
1473
1474#if defined(MBEDTLS_DEPRECATED_WARNING)
1475#define MBEDTLS_DEPRECATED __attribute__((deprecated))
1476#else
1477#define MBEDTLS_DEPRECATED
1478#endif /* MBEDTLS_DEPRECATED_WARNING */
1479
1480MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_init)(
1481 mbedtls_ssl_context *ssl,
1482 const unsigned char *key_enc, const unsigned char *key_dec,
1483 size_t keylen,
1484 const unsigned char *iv_enc, const unsigned char *iv_dec,
1485 size_t ivlen,
1486 const unsigned char *mac_enc, const unsigned char *mac_dec,
1487 size_t maclen);
1488MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_activate)(
1489 mbedtls_ssl_context *ssl,
1490 int direction);
1491MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_reset)(
1492 mbedtls_ssl_context *ssl);
1493MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_write)(
1494 mbedtls_ssl_context *ssl);
1495MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_read)(
1496 mbedtls_ssl_context *ssl);
1497MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_finish)(
1498 mbedtls_ssl_context *ssl);
1499
1500#undef MBEDTLS_DEPRECATED
1501#endif /* !MBEDTLS_DEPRECATED_REMOVED */
1502
1503#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
1504
1505/**
1506 * \brief Return the name of the ciphersuite associated with the
1507 * given ID
1508 *
1509 * \param ciphersuite_id SSL ciphersuite ID
1510 *
1511 * \return a string containing the ciphersuite name
1512 */
1513const char *mbedtls_ssl_get_ciphersuite_name(const int ciphersuite_id);
1514
1515/**
1516 * \brief Return the ID of the ciphersuite associated with the
1517 * given name
1518 *
1519 * \param ciphersuite_name SSL ciphersuite name
1520 *
1521 * \return the ID with the ciphersuite or 0 if not found
1522 */
1523int mbedtls_ssl_get_ciphersuite_id(const char *ciphersuite_name);
1524
1525/**
1526 * \brief Initialize an SSL context
1527 * Just makes the context ready for mbedtls_ssl_setup() or
1528 * mbedtls_ssl_free()
1529 *
1530 * \param ssl SSL context
1531 */
1532void mbedtls_ssl_init(mbedtls_ssl_context *ssl);
1533
1534/**
1535 * \brief Set up an SSL context for use
1536 *
1537 * \note No copy of the configuration context is made, it can be
1538 * shared by many mbedtls_ssl_context structures.
1539 *
1540 * \warning The conf structure will be accessed during the session.
1541 * It must not be modified or freed as long as the session
1542 * is active.
1543 *
1544 * \warning This function must be called exactly once per context.
1545 * Calling mbedtls_ssl_setup again is not supported, even
1546 * if no session is active.
1547 *
1548 * \note If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto
1549 * subsystem must have been initialized by calling
1550 * psa_crypto_init() before calling this function.
1551 *
1552 * \param ssl SSL context
1553 * \param conf SSL configuration to use
1554 *
1555 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED if
1556 * memory allocation failed
1557 */
1558int mbedtls_ssl_setup(mbedtls_ssl_context *ssl,
1559 const mbedtls_ssl_config *conf);
1560
1561/**
1562 * \brief Reset an already initialized SSL context for re-use
1563 * while retaining application-set variables, function
1564 * pointers and data.
1565 *
1566 * \param ssl SSL context
1567 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED,
1568 MBEDTLS_ERR_SSL_HW_ACCEL_FAILED or
1569 * MBEDTLS_ERR_SSL_COMPRESSION_FAILED
1570 */
1571int mbedtls_ssl_session_reset(mbedtls_ssl_context *ssl);
1572
1573/**
1574 * \brief Set the current endpoint type
1575 *
1576 * \param conf SSL configuration
1577 * \param endpoint must be MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
1578 */
1579void mbedtls_ssl_conf_endpoint(mbedtls_ssl_config *conf, int endpoint);
1580
1581/**
1582 * \brief Set the transport type (TLS or DTLS).
1583 * Default: TLS
1584 *
1585 * \note For DTLS, you must either provide a recv callback that
1586 * doesn't block, or one that handles timeouts, see
1587 * \c mbedtls_ssl_set_bio(). You also need to provide timer
1588 * callbacks with \c mbedtls_ssl_set_timer_cb().
1589 *
1590 * \param conf SSL configuration
1591 * \param transport transport type:
1592 * MBEDTLS_SSL_TRANSPORT_STREAM for TLS,
1593 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS.
1594 */
1595void mbedtls_ssl_conf_transport(mbedtls_ssl_config *conf, int transport);
1596
1597/**
1598 * \brief Set the certificate verification mode
1599 * Default: NONE on server, REQUIRED on client
1600 *
1601 * \param conf SSL configuration
1602 * \param authmode can be:
1603 *
1604 * MBEDTLS_SSL_VERIFY_NONE: peer certificate is not checked
1605 * (default on server)
1606 * (insecure on client)
1607 *
1608 * MBEDTLS_SSL_VERIFY_OPTIONAL: peer certificate is checked, however the
1609 * handshake continues even if verification failed;
1610 * mbedtls_ssl_get_verify_result() can be called after the
1611 * handshake is complete.
1612 *
1613 * MBEDTLS_SSL_VERIFY_REQUIRED: peer *must* present a valid certificate,
1614 * handshake is aborted if verification failed.
1615 * (default on client)
1616 *
1617 * \note On client, MBEDTLS_SSL_VERIFY_REQUIRED is the recommended mode.
1618 * With MBEDTLS_SSL_VERIFY_OPTIONAL, the user needs to call mbedtls_ssl_get_verify_result() at
1619 * the right time(s), which may not be obvious, while REQUIRED always perform
1620 * the verification as soon as possible. For example, REQUIRED was protecting
1621 * against the "triple handshake" attack even before it was found.
1622 */
1623void mbedtls_ssl_conf_authmode(mbedtls_ssl_config *conf, int authmode);
1624
1625#if defined(MBEDTLS_X509_CRT_PARSE_C)
1626/**
1627 * \brief Set the verification callback (Optional).
1628 *
1629 * If set, the provided verify callback is called for each
1630 * certificate in the peer's CRT chain, including the trusted
1631 * root. For more information, please see the documentation of
1632 * \c mbedtls_x509_crt_verify().
1633 *
1634 * \note For per context callbacks and contexts, please use
1635 * mbedtls_ssl_set_verify() instead.
1636 *
1637 * \param conf The SSL configuration to use.
1638 * \param f_vrfy The verification callback to use during CRT verification.
1639 * \param p_vrfy The opaque context to be passed to the callback.
1640 */
1641void mbedtls_ssl_conf_verify(mbedtls_ssl_config *conf,
1642 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
1643 void *p_vrfy);
1644#endif /* MBEDTLS_X509_CRT_PARSE_C */
1645
1646/**
1647 * \brief Set the random number generator callback
1648 *
1649 * \param conf SSL configuration
1650 * \param f_rng RNG function
1651 * \param p_rng RNG parameter
1652 */
1653void mbedtls_ssl_conf_rng(mbedtls_ssl_config *conf,
1654 int (*f_rng)(void *, unsigned char *, size_t),
1655 void *p_rng);
1656
1657/**
1658 * \brief Set the debug callback
1659 *
1660 * The callback has the following argument:
1661 * void * opaque context for the callback
1662 * int debug level
1663 * const char * file name
1664 * int line number
1665 * const char * message
1666 *
1667 * \param conf SSL configuration
1668 * \param f_dbg debug function
1669 * \param p_dbg debug parameter
1670 */
1671void mbedtls_ssl_conf_dbg(mbedtls_ssl_config *conf,
1672 void (*f_dbg)(void *, int, const char *, int, const char *),
1673 void *p_dbg);
1674
1675/**
1676 * \brief Set the underlying BIO callbacks for write, read and
1677 * read-with-timeout.
1678 *
1679 * \param ssl SSL context
1680 * \param p_bio parameter (context) shared by BIO callbacks
1681 * \param f_send write callback
1682 * \param f_recv read callback
1683 * \param f_recv_timeout blocking read callback with timeout.
1684 *
1685 * \note One of f_recv or f_recv_timeout can be NULL, in which case
1686 * the other is used. If both are non-NULL, f_recv_timeout is
1687 * used and f_recv is ignored (as if it were NULL).
1688 *
1689 * \note The two most common use cases are:
1690 * - non-blocking I/O, f_recv != NULL, f_recv_timeout == NULL
1691 * - blocking I/O, f_recv == NULL, f_recv_timeout != NULL
1692 *
1693 * \note For DTLS, you need to provide either a non-NULL
1694 * f_recv_timeout callback, or a f_recv that doesn't block.
1695 *
1696 * \note See the documentations of \c mbedtls_ssl_send_t,
1697 * \c mbedtls_ssl_recv_t and \c mbedtls_ssl_recv_timeout_t for
1698 * the conventions those callbacks must follow.
1699 *
1700 * \note On some platforms, net_sockets.c provides
1701 * \c mbedtls_net_send(), \c mbedtls_net_recv() and
1702 * \c mbedtls_net_recv_timeout() that are suitable to be used
1703 * here.
1704 */
1705void mbedtls_ssl_set_bio(mbedtls_ssl_context *ssl,
1706 void *p_bio,
1707 mbedtls_ssl_send_t *f_send,
1708 mbedtls_ssl_recv_t *f_recv,
1709 mbedtls_ssl_recv_timeout_t *f_recv_timeout);
1710
1711#if defined(MBEDTLS_SSL_PROTO_DTLS)
1712
1713#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1714
1715
1716/**
1717 * \brief Configure the use of the Connection ID (CID)
1718 * extension in the next handshake.
1719 *
1720 * Reference: draft-ietf-tls-dtls-connection-id-05
1721 * https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05
1722 *
1723 * The DTLS CID extension allows the reliable association of
1724 * DTLS records to DTLS connections across changes in the
1725 * underlying transport (changed IP and Port metadata) by
1726 * adding explicit connection identifiers (CIDs) to the
1727 * headers of encrypted DTLS records. The desired CIDs are
1728 * configured by the application layer and are exchanged in
1729 * new `ClientHello` / `ServerHello` extensions during the
1730 * handshake, where each side indicates the CID it wants the
1731 * peer to use when writing encrypted messages. The CIDs are
1732 * put to use once records get encrypted: the stack discards
1733 * any incoming records that don't include the configured CID
1734 * in their header, and adds the peer's requested CID to the
1735 * headers of outgoing messages.
1736 *
1737 * This API enables or disables the use of the CID extension
1738 * in the next handshake and sets the value of the CID to
1739 * be used for incoming messages.
1740 *
1741 * \param ssl The SSL context to configure. This must be initialized.
1742 * \param enable This value determines whether the CID extension should
1743 * be used or not. Possible values are:
1744 * - MBEDTLS_SSL_CID_ENABLED to enable the use of the CID.
1745 * - MBEDTLS_SSL_CID_DISABLED (default) to disable the use
1746 * of the CID.
1747 * \param own_cid The address of the readable buffer holding the CID we want
1748 * the peer to use when sending encrypted messages to us.
1749 * This may be \c NULL if \p own_cid_len is \c 0.
1750 * This parameter is unused if \p enable is set to
1751 * MBEDTLS_SSL_CID_DISABLED.
1752 * \param own_cid_len The length of \p own_cid.
1753 * This parameter is unused if \p enable is set to
1754 * MBEDTLS_SSL_CID_DISABLED.
1755 *
1756 * \note The value of \p own_cid_len must match the value of the
1757 * \c len parameter passed to mbedtls_ssl_conf_cid()
1758 * when configuring the ::mbedtls_ssl_config that \p ssl
1759 * is bound to.
1760 *
1761 * \note This CID configuration applies to subsequent handshakes
1762 * performed on the SSL context \p ssl, but does not trigger
1763 * one. You still have to call `mbedtls_ssl_handshake()`
1764 * (for the initial handshake) or `mbedtls_ssl_renegotiate()`
1765 * (for a renegotiation handshake) explicitly after a
1766 * successful call to this function to run the handshake.
1767 *
1768 * \note This call cannot guarantee that the use of the CID
1769 * will be successfully negotiated in the next handshake,
1770 * because the peer might not support it. Specifically:
1771 * - On the Client, enabling the use of the CID through
1772 * this call implies that the `ClientHello` in the next
1773 * handshake will include the CID extension, thereby
1774 * offering the use of the CID to the server. Only if
1775 * the `ServerHello` contains the CID extension, too,
1776 * the CID extension will actually be put to use.
1777 * - On the Server, enabling the use of the CID through
1778 * this call implies that that the server will look for
1779 * the CID extension in a `ClientHello` from the client,
1780 * and, if present, reply with a CID extension in its
1781 * `ServerHello`.
1782 *
1783 * \note To check whether the use of the CID was negotiated
1784 * after the subsequent handshake has completed, please
1785 * use the API mbedtls_ssl_get_peer_cid().
1786 *
1787 * \warning If the use of the CID extension is enabled in this call
1788 * and the subsequent handshake negotiates its use, Mbed TLS
1789 * will silently drop every packet whose CID does not match
1790 * the CID configured in \p own_cid. It is the responsibility
1791 * of the user to adapt the underlying transport to take care
1792 * of CID-based demultiplexing before handing datagrams to
1793 * Mbed TLS.
1794 *
1795 * \return \c 0 on success. In this case, the CID configuration
1796 * applies to the next handshake.
1797 * \return A negative error code on failure.
1798 */
1799int mbedtls_ssl_set_cid(mbedtls_ssl_context *ssl,
1800 int enable,
1801 unsigned char const *own_cid,
1802 size_t own_cid_len);
1803
1804/**
1805 * \brief Get information about the use of the CID extension
1806 * in the current connection.
1807 *
1808 * \param ssl The SSL context to query.
1809 * \param enabled The address at which to store whether the CID extension
1810 * is currently in use or not. If the CID is in use,
1811 * `*enabled` is set to MBEDTLS_SSL_CID_ENABLED;
1812 * otherwise, it is set to MBEDTLS_SSL_CID_DISABLED.
1813 * \param peer_cid The address of the buffer in which to store the CID
1814 * chosen by the peer (if the CID extension is used).
1815 * This may be \c NULL in case the value of peer CID
1816 * isn't needed. If it is not \c NULL, \p peer_cid_len
1817 * must not be \c NULL.
1818 * \param peer_cid_len The address at which to store the size of the CID
1819 * chosen by the peer (if the CID extension is used).
1820 * This is also the number of Bytes in \p peer_cid that
1821 * have been written.
1822 * This may be \c NULL in case the length of the peer CID
1823 * isn't needed. If it is \c NULL, \p peer_cid must be
1824 * \c NULL, too.
1825 *
1826 * \note This applies to the state of the CID negotiated in
1827 * the last complete handshake. If a handshake is in
1828 * progress, this function will attempt to complete
1829 * the handshake first.
1830 *
1831 * \note If CID extensions have been exchanged but both client
1832 * and server chose to use an empty CID, this function
1833 * sets `*enabled` to #MBEDTLS_SSL_CID_DISABLED
1834 * (the rationale for this is that the resulting
1835 * communication is the same as if the CID extensions
1836 * hadn't been used).
1837 *
1838 * \return \c 0 on success.
1839 * \return A negative error code on failure.
1840 */
1841int mbedtls_ssl_get_peer_cid(mbedtls_ssl_context *ssl,
1842 int *enabled,
1843 unsigned char peer_cid[MBEDTLS_SSL_CID_OUT_LEN_MAX],
1844 size_t *peer_cid_len);
1845
1846#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1847
1848/**
1849 * \brief Set the Maximum Transport Unit (MTU).
1850 * Special value: 0 means unset (no limit).
1851 * This represents the maximum size of a datagram payload
1852 * handled by the transport layer (usually UDP) as determined
1853 * by the network link and stack. In practice, this controls
1854 * the maximum size datagram the DTLS layer will pass to the
1855 * \c f_send() callback set using \c mbedtls_ssl_set_bio().
1856 *
1857 * \note The limit on datagram size is converted to a limit on
1858 * record payload by subtracting the current overhead of
1859 * encapsulation and encryption/authentication if any.
1860 *
1861 * \note This can be called at any point during the connection, for
1862 * example when a Path Maximum Transfer Unit (PMTU)
1863 * estimate becomes available from other sources,
1864 * such as lower (or higher) protocol layers.
1865 *
1866 * \note This setting only controls the size of the packets we send,
1867 * and does not restrict the size of the datagrams we're
1868 * willing to receive. Client-side, you can request the
1869 * server to use smaller records with \c
1870 * mbedtls_ssl_conf_max_frag_len().
1871 *
1872 * \note If both a MTU and a maximum fragment length have been
1873 * configured (or negotiated with the peer), the resulting
1874 * lower limit on record payload (see first note) is used.
1875 *
1876 * \note This can only be used to decrease the maximum size
1877 * of datagrams (hence records, see first note) sent. It
1878 * cannot be used to increase the maximum size of records over
1879 * the limit set by #MBEDTLS_SSL_OUT_CONTENT_LEN.
1880 *
1881 * \note Values lower than the current record layer expansion will
1882 * result in an error when trying to send data.
1883 *
1884 * \note Using record compression together with a non-zero MTU value
1885 * will result in an error when trying to send data.
1886 *
1887 * \param ssl SSL context
1888 * \param mtu Value of the path MTU in bytes
1889 */
1890void mbedtls_ssl_set_mtu(mbedtls_ssl_context *ssl, uint16_t mtu);
1891#endif /* MBEDTLS_SSL_PROTO_DTLS */
1892
1893#if defined(MBEDTLS_X509_CRT_PARSE_C)
1894/**
1895 * \brief Set a connection-specific verification callback (optional).
1896 *
1897 * If set, the provided verify callback is called for each
1898 * certificate in the peer's CRT chain, including the trusted
1899 * root. For more information, please see the documentation of
1900 * \c mbedtls_x509_crt_verify().
1901 *
1902 * \note This call is analogous to mbedtls_ssl_conf_verify() but
1903 * binds the verification callback and context to an SSL context
1904 * as opposed to an SSL configuration.
1905 * If mbedtls_ssl_conf_verify() and mbedtls_ssl_set_verify()
1906 * are both used, mbedtls_ssl_set_verify() takes precedence.
1907 *
1908 * \param ssl The SSL context to use.
1909 * \param f_vrfy The verification callback to use during CRT verification.
1910 * \param p_vrfy The opaque context to be passed to the callback.
1911 */
1912void mbedtls_ssl_set_verify(mbedtls_ssl_context *ssl,
1913 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
1914 void *p_vrfy);
1915#endif /* MBEDTLS_X509_CRT_PARSE_C */
1916
1917/**
1918 * \brief Set the timeout period for mbedtls_ssl_read()
1919 * (Default: no timeout.)
1920 *
1921 * \param conf SSL configuration context
1922 * \param timeout Timeout value in milliseconds.
1923 * Use 0 for no timeout (default).
1924 *
1925 * \note With blocking I/O, this will only work if a non-NULL
1926 * \c f_recv_timeout was set with \c mbedtls_ssl_set_bio().
1927 * With non-blocking I/O, this will only work if timer
1928 * callbacks were set with \c mbedtls_ssl_set_timer_cb().
1929 *
1930 * \note With non-blocking I/O, you may also skip this function
1931 * altogether and handle timeouts at the application layer.
1932 */
1933void mbedtls_ssl_conf_read_timeout(mbedtls_ssl_config *conf, uint32_t timeout);
1934
1935#if defined(MBEDTLS_SSL_RECORD_CHECKING)
1936/**
1937 * \brief Check whether a buffer contains a valid and authentic record
1938 * that has not been seen before. (DTLS only).
1939 *
1940 * This function does not change the user-visible state
1941 * of the SSL context. Its sole purpose is to provide
1942 * an indication of the legitimacy of an incoming record.
1943 *
1944 * This can be useful e.g. in distributed server environments
1945 * using the DTLS Connection ID feature, in which connections
1946 * might need to be passed between service instances on a change
1947 * of peer address, but where such disruptive operations should
1948 * only happen after the validity of incoming records has been
1949 * confirmed.
1950 *
1951 * \param ssl The SSL context to use.
1952 * \param buf The address of the buffer holding the record to be checked.
1953 * This must be a read/write buffer of length \p buflen Bytes.
1954 * \param buflen The length of \p buf in Bytes.
1955 *
1956 * \note This routine only checks whether the provided buffer begins
1957 * with a valid and authentic record that has not been seen
1958 * before, but does not check potential data following the
1959 * initial record. In particular, it is possible to pass DTLS
1960 * datagrams containing multiple records, in which case only
1961 * the first record is checked.
1962 *
1963 * \note This function modifies the input buffer \p buf. If you need
1964 * to preserve the original record, you have to maintain a copy.
1965 *
1966 * \return \c 0 if the record is valid and authentic and has not been
1967 * seen before.
1968 * \return MBEDTLS_ERR_SSL_INVALID_MAC if the check completed
1969 * successfully but the record was found to be not authentic.
1970 * \return MBEDTLS_ERR_SSL_INVALID_RECORD if the check completed
1971 * successfully but the record was found to be invalid for
1972 * a reason different from authenticity checking.
1973 * \return MBEDTLS_ERR_SSL_UNEXPECTED_RECORD if the check completed
1974 * successfully but the record was found to be unexpected
1975 * in the state of the SSL context, including replayed records.
1976 * \return Another negative error code on different kinds of failure.
1977 * In this case, the SSL context becomes unusable and needs
1978 * to be freed or reset before reuse.
1979 */
1980int mbedtls_ssl_check_record(mbedtls_ssl_context const *ssl,
1981 unsigned char *buf,
1982 size_t buflen);
1983#endif /* MBEDTLS_SSL_RECORD_CHECKING */
1984
1985/**
1986 * \brief Set the timer callbacks (Mandatory for DTLS.)
1987 *
1988 * \param ssl SSL context
1989 * \param p_timer parameter (context) shared by timer callbacks
1990 * \param f_set_timer set timer callback
1991 * \param f_get_timer get timer callback. Must return:
1992 *
1993 * \note See the documentation of \c mbedtls_ssl_set_timer_t and
1994 * \c mbedtls_ssl_get_timer_t for the conventions this pair of
1995 * callbacks must follow.
1996 *
1997 * \note On some platforms, timing.c provides
1998 * \c mbedtls_timing_set_delay() and
1999 * \c mbedtls_timing_get_delay() that are suitable for using
2000 * here, except if using an event-driven style.
2001 *
2002 * \note See also the "DTLS tutorial" article in our knowledge base.
2003 * https://mbed-tls.readthedocs.io/en/latest/kb/how-to/dtls-tutorial
2004 */
2005void mbedtls_ssl_set_timer_cb(mbedtls_ssl_context *ssl,
2006 void *p_timer,
2007 mbedtls_ssl_set_timer_t *f_set_timer,
2008 mbedtls_ssl_get_timer_t *f_get_timer);
2009
2010/**
2011 * \brief Callback type: generate and write session ticket
2012 *
2013 * \note This describes what a callback implementation should do.
2014 * This callback should generate an encrypted and
2015 * authenticated ticket for the session and write it to the
2016 * output buffer. Here, ticket means the opaque ticket part
2017 * of the NewSessionTicket structure of RFC 5077.
2018 *
2019 * \param p_ticket Context for the callback
2020 * \param session SSL session to be written in the ticket
2021 * \param start Start of the output buffer
2022 * \param end End of the output buffer
2023 * \param tlen On exit, holds the length written
2024 * \param lifetime On exit, holds the lifetime of the ticket in seconds
2025 *
2026 * \return 0 if successful, or
2027 * a specific MBEDTLS_ERR_XXX code.
2028 */
2029typedef int mbedtls_ssl_ticket_write_t(void *p_ticket,
2030 const mbedtls_ssl_session *session,
2031 unsigned char *start,
2032 const unsigned char *end,
2033 size_t *tlen,
2034 uint32_t *lifetime);
2035
2036#if defined(MBEDTLS_SSL_EXPORT_KEYS)
2037/**
2038 * \brief Callback type: Export key block and master secret
2039 *
2040 * \note This is required for certain uses of TLS, e.g. EAP-TLS
2041 * (RFC 5216) and Thread. The key pointers are ephemeral and
2042 * therefore must not be stored. The master secret and keys
2043 * should not be used directly except as an input to a key
2044 * derivation function.
2045 *
2046 * \param p_expkey Context for the callback
2047 * \param ms Pointer to master secret (fixed length: 48 bytes)
2048 * \param kb Pointer to key block, see RFC 5246 section 6.3
2049 * (variable length: 2 * maclen + 2 * keylen + 2 * ivlen).
2050 * \param maclen MAC length
2051 * \param keylen Key length
2052 * \param ivlen IV length
2053 *
2054 * \return 0 if successful, or
2055 * a specific MBEDTLS_ERR_XXX code.
2056 */
2057typedef int mbedtls_ssl_export_keys_t(void *p_expkey,
2058 const unsigned char *ms,
2059 const unsigned char *kb,
2060 size_t maclen,
2061 size_t keylen,
2062 size_t ivlen);
2063
2064/**
2065 * \brief Callback type: Export key block, master secret,
2066 * handshake randbytes and the tls_prf function
2067 * used to derive keys.
2068 *
2069 * \note This is required for certain uses of TLS, e.g. EAP-TLS
2070 * (RFC 5216) and Thread. The key pointers are ephemeral and
2071 * therefore must not be stored. The master secret and keys
2072 * should not be used directly except as an input to a key
2073 * derivation function.
2074 *
2075 * \param p_expkey Context for the callback.
2076 * \param ms Pointer to master secret (fixed length: 48 bytes).
2077 * \param kb Pointer to key block, see RFC 5246 section 6.3.
2078 * (variable length: 2 * maclen + 2 * keylen + 2 * ivlen).
2079 * \param maclen MAC length.
2080 * \param keylen Key length.
2081 * \param ivlen IV length.
2082 * \param client_random The client random bytes.
2083 * \param server_random The server random bytes.
2084 * \param tls_prf_type The tls_prf enum type.
2085 *
2086 * \return 0 if successful, or
2087 * a specific MBEDTLS_ERR_XXX code.
2088 */
2089typedef int mbedtls_ssl_export_keys_ext_t(void *p_expkey,
2090 const unsigned char *ms,
2091 const unsigned char *kb,
2092 size_t maclen,
2093 size_t keylen,
2094 size_t ivlen,
2095 const unsigned char client_random[32],
2096 const unsigned char server_random[32],
2097 mbedtls_tls_prf_types tls_prf_type);
2098#endif /* MBEDTLS_SSL_EXPORT_KEYS */
2099
2100/**
2101 * \brief Callback type: parse and load session ticket
2102 *
2103 * \note This describes what a callback implementation should do.
2104 * This callback should parse a session ticket as generated
2105 * by the corresponding mbedtls_ssl_ticket_write_t function,
2106 * and, if the ticket is authentic and valid, load the
2107 * session.
2108 *
2109 * \note The implementation is allowed to modify the first len
2110 * bytes of the input buffer, eg to use it as a temporary
2111 * area for the decrypted ticket contents.
2112 *
2113 * \param p_ticket Context for the callback
2114 * \param session SSL session to be loaded
2115 * \param buf Start of the buffer containing the ticket
2116 * \param len Length of the ticket.
2117 *
2118 * \return 0 if successful, or
2119 * MBEDTLS_ERR_SSL_INVALID_MAC if not authentic, or
2120 * MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED if expired, or
2121 * any other non-zero code for other failures.
2122 */
2123typedef int mbedtls_ssl_ticket_parse_t(void *p_ticket,
2124 mbedtls_ssl_session *session,
2125 unsigned char *buf,
2126 size_t len);
2127
2128#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)
2129/**
2130 * \brief Configure SSL session ticket callbacks (server only).
2131 * (Default: none.)
2132 *
2133 * \note On server, session tickets are enabled by providing
2134 * non-NULL callbacks.
2135 *
2136 * \note On client, use \c mbedtls_ssl_conf_session_tickets().
2137 *
2138 * \param conf SSL configuration context
2139 * \param f_ticket_write Callback for writing a ticket
2140 * \param f_ticket_parse Callback for parsing a ticket
2141 * \param p_ticket Context shared by the two callbacks
2142 */
2143void mbedtls_ssl_conf_session_tickets_cb(mbedtls_ssl_config *conf,
2144 mbedtls_ssl_ticket_write_t *f_ticket_write,
2145 mbedtls_ssl_ticket_parse_t *f_ticket_parse,
2146 void *p_ticket);
2147#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
2148
2149#if defined(MBEDTLS_SSL_EXPORT_KEYS)
2150/**
2151 * \brief Configure key export callback.
2152 * (Default: none.)
2153 *
2154 * \note See \c mbedtls_ssl_export_keys_t.
2155 *
2156 * \param conf SSL configuration context
2157 * \param f_export_keys Callback for exporting keys
2158 * \param p_export_keys Context for the callback
2159 */
2160void mbedtls_ssl_conf_export_keys_cb(mbedtls_ssl_config *conf,
2161 mbedtls_ssl_export_keys_t *f_export_keys,
2162 void *p_export_keys);
2163
2164/**
2165 * \brief Configure extended key export callback.
2166 * (Default: none.)
2167 *
2168 * \note See \c mbedtls_ssl_export_keys_ext_t.
2169 * \warning Exported key material must not be used for any purpose
2170 * before the (D)TLS handshake is completed
2171 *
2172 * \param conf SSL configuration context
2173 * \param f_export_keys_ext Callback for exporting keys
2174 * \param p_export_keys Context for the callback
2175 */
2176void mbedtls_ssl_conf_export_keys_ext_cb(mbedtls_ssl_config *conf,
2177 mbedtls_ssl_export_keys_ext_t *f_export_keys_ext,
2178 void *p_export_keys);
2179#endif /* MBEDTLS_SSL_EXPORT_KEYS */
2180
2181#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
2182/**
2183 * \brief Configure asynchronous private key operation callbacks.
2184 *
2185 * \param conf SSL configuration context
2186 * \param f_async_sign Callback to start a signature operation. See
2187 * the description of ::mbedtls_ssl_async_sign_t
2188 * for more information. This may be \c NULL if the
2189 * external processor does not support any signature
2190 * operation; in this case the private key object
2191 * associated with the certificate will be used.
2192 * \param f_async_decrypt Callback to start a decryption operation. See
2193 * the description of ::mbedtls_ssl_async_decrypt_t
2194 * for more information. This may be \c NULL if the
2195 * external processor does not support any decryption
2196 * operation; in this case the private key object
2197 * associated with the certificate will be used.
2198 * \param f_async_resume Callback to resume an asynchronous operation. See
2199 * the description of ::mbedtls_ssl_async_resume_t
2200 * for more information. This may not be \c NULL unless
2201 * \p f_async_sign and \p f_async_decrypt are both
2202 * \c NULL.
2203 * \param f_async_cancel Callback to cancel an asynchronous operation. See
2204 * the description of ::mbedtls_ssl_async_cancel_t
2205 * for more information. This may be \c NULL if
2206 * no cleanup is needed.
2207 * \param config_data A pointer to configuration data which can be
2208 * retrieved with
2209 * mbedtls_ssl_conf_get_async_config_data(). The
2210 * library stores this value without dereferencing it.
2211 */
2212void mbedtls_ssl_conf_async_private_cb(mbedtls_ssl_config *conf,
2213 mbedtls_ssl_async_sign_t *f_async_sign,
2214 mbedtls_ssl_async_decrypt_t *f_async_decrypt,
2215 mbedtls_ssl_async_resume_t *f_async_resume,
2216 mbedtls_ssl_async_cancel_t *f_async_cancel,
2217 void *config_data);
2218
2219/**
2220 * \brief Retrieve the configuration data set by
2221 * mbedtls_ssl_conf_async_private_cb().
2222 *
2223 * \param conf SSL configuration context
2224 * \return The configuration data set by
2225 * mbedtls_ssl_conf_async_private_cb().
2226 */
2227void *mbedtls_ssl_conf_get_async_config_data(const mbedtls_ssl_config *conf);
2228
2229/**
2230 * \brief Retrieve the asynchronous operation user context.
2231 *
2232 * \note This function may only be called while a handshake
2233 * is in progress.
2234 *
2235 * \param ssl The SSL context to access.
2236 *
2237 * \return The asynchronous operation user context that was last
2238 * set during the current handshake. If
2239 * mbedtls_ssl_set_async_operation_data() has not yet been
2240 * called during the current handshake, this function returns
2241 * \c NULL.
2242 */
2243void *mbedtls_ssl_get_async_operation_data(const mbedtls_ssl_context *ssl);
2244
2245/**
2246 * \brief Retrieve the asynchronous operation user context.
2247 *
2248 * \note This function may only be called while a handshake
2249 * is in progress.
2250 *
2251 * \param ssl The SSL context to access.
2252 * \param ctx The new value of the asynchronous operation user context.
2253 * Call mbedtls_ssl_get_async_operation_data() later during the
2254 * same handshake to retrieve this value.
2255 */
2256void mbedtls_ssl_set_async_operation_data(mbedtls_ssl_context *ssl,
2257 void *ctx);
2258#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
2259
2260/**
2261 * \brief Callback type: generate a cookie
2262 *
2263 * \param ctx Context for the callback
2264 * \param p Buffer to write to,
2265 * must be updated to point right after the cookie
2266 * \param end Pointer to one past the end of the output buffer
2267 * \param info Client ID info that was passed to
2268 * \c mbedtls_ssl_set_client_transport_id()
2269 * \param ilen Length of info in bytes
2270 *
2271 * \return The callback must return 0 on success,
2272 * or a negative error code.
2273 */
2274typedef int mbedtls_ssl_cookie_write_t(void *ctx,
2275 unsigned char **p, unsigned char *end,
2276 const unsigned char *info, size_t ilen);
2277
2278/**
2279 * \brief Callback type: verify a cookie
2280 *
2281 * \param ctx Context for the callback
2282 * \param cookie Cookie to verify
2283 * \param clen Length of cookie
2284 * \param info Client ID info that was passed to
2285 * \c mbedtls_ssl_set_client_transport_id()
2286 * \param ilen Length of info in bytes
2287 *
2288 * \return The callback must return 0 if cookie is valid,
2289 * or a negative error code.
2290 */
2291typedef int mbedtls_ssl_cookie_check_t(void *ctx,
2292 const unsigned char *cookie, size_t clen,
2293 const unsigned char *info, size_t ilen);
2294
2295#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
2296/**
2297 * \brief Register callbacks for DTLS cookies
2298 * (Server only. DTLS only.)
2299 *
2300 * Default: dummy callbacks that fail, in order to force you to
2301 * register working callbacks (and initialize their context).
2302 *
2303 * To disable HelloVerifyRequest, register NULL callbacks.
2304 *
2305 * \warning Disabling hello verification allows your server to be used
2306 * for amplification in DoS attacks against other hosts.
2307 * Only disable if you known this can't happen in your
2308 * particular environment.
2309 *
2310 * \note See comments on \c mbedtls_ssl_handshake() about handling
2311 * the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected
2312 * on the first handshake attempt when this is enabled.
2313 *
2314 * \note This is also necessary to handle client reconnection from
2315 * the same port as described in RFC 6347 section 4.2.8 (only
2316 * the variant with cookies is supported currently). See
2317 * comments on \c mbedtls_ssl_read() for details.
2318 *
2319 * \param conf SSL configuration
2320 * \param f_cookie_write Cookie write callback
2321 * \param f_cookie_check Cookie check callback
2322 * \param p_cookie Context for both callbacks
2323 */
2324void mbedtls_ssl_conf_dtls_cookies(mbedtls_ssl_config *conf,
2325 mbedtls_ssl_cookie_write_t *f_cookie_write,
2326 mbedtls_ssl_cookie_check_t *f_cookie_check,
2327 void *p_cookie);
2328
2329/**
2330 * \brief Set client's transport-level identification info.
2331 * (Server only. DTLS only.)
2332 *
2333 * This is usually the IP address (and port), but could be
2334 * anything identify the client depending on the underlying
2335 * network stack. Used for HelloVerifyRequest with DTLS.
2336 * This is *not* used to route the actual packets.
2337 *
2338 * \param ssl SSL context
2339 * \param info Transport-level info identifying the client (eg IP + port)
2340 * \param ilen Length of info in bytes
2341 *
2342 * \note An internal copy is made, so the info buffer can be reused.
2343 *
2344 * \return 0 on success,
2345 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client,
2346 * MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory.
2347 */
2348int mbedtls_ssl_set_client_transport_id(mbedtls_ssl_context *ssl,
2349 const unsigned char *info,
2350 size_t ilen);
2351
2352#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
2353
2354#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
2355/**
2356 * \brief Enable or disable anti-replay protection for DTLS.
2357 * (DTLS only, no effect on TLS.)
2358 * Default: enabled.
2359 *
2360 * \param conf SSL configuration
2361 * \param mode MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED.
2362 *
2363 * \warning Disabling this is a security risk unless the application
2364 * protocol handles duplicated packets in a safe way. You
2365 * should not disable this without careful consideration.
2366 * However, if your application already detects duplicated
2367 * packets and needs information about them to adjust its
2368 * transmission strategy, then you'll want to disable this.
2369 */
2370void mbedtls_ssl_conf_dtls_anti_replay(mbedtls_ssl_config *conf, char mode);
2371#endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
2372
2373#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
2374/**
2375 * \brief Set a limit on the number of records with a bad MAC
2376 * before terminating the connection.
2377 * (DTLS only, no effect on TLS.)
2378 * Default: 0 (disabled).
2379 *
2380 * \param conf SSL configuration
2381 * \param limit Limit, or 0 to disable.
2382 *
2383 * \note If the limit is N, then the connection is terminated when
2384 * the Nth non-authentic record is seen.
2385 *
2386 * \note Records with an invalid header are not counted, only the
2387 * ones going through the authentication-decryption phase.
2388 *
2389 * \note This is a security trade-off related to the fact that it's
2390 * often relatively easy for an active attacker to inject UDP
2391 * datagrams. On one hand, setting a low limit here makes it
2392 * easier for such an attacker to forcibly terminated a
2393 * connection. On the other hand, a high limit or no limit
2394 * might make us waste resources checking authentication on
2395 * many bogus packets.
2396 */
2397void mbedtls_ssl_conf_dtls_badmac_limit(mbedtls_ssl_config *conf, unsigned limit);
2398#endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */
2399
2400#if defined(MBEDTLS_SSL_PROTO_DTLS)
2401
2402/**
2403 * \brief Allow or disallow packing of multiple handshake records
2404 * within a single datagram.
2405 *
2406 * \param ssl The SSL context to configure.
2407 * \param allow_packing This determines whether datagram packing may
2408 * be used or not. A value of \c 0 means that every
2409 * record will be sent in a separate datagram; a
2410 * value of \c 1 means that, if space permits,
2411 * multiple handshake messages (including CCS) belonging to
2412 * a single flight may be packed within a single datagram.
2413 *
2414 * \note This is enabled by default and should only be disabled
2415 * for test purposes, or if datagram packing causes
2416 * interoperability issues with peers that don't support it.
2417 *
2418 * \note Allowing datagram packing reduces the network load since
2419 * there's less overhead if multiple messages share the same
2420 * datagram. Also, it increases the handshake efficiency
2421 * since messages belonging to a single datagram will not
2422 * be reordered in transit, and so future message buffering
2423 * or flight retransmission (if no buffering is used) as
2424 * means to deal with reordering are needed less frequently.
2425 *
2426 * \note Application records are not affected by this option and
2427 * are currently always sent in separate datagrams.
2428 *
2429 */
2430void mbedtls_ssl_set_datagram_packing(mbedtls_ssl_context *ssl,
2431 unsigned allow_packing);
2432
2433/**
2434 * \brief Set retransmit timeout values for the DTLS handshake.
2435 * (DTLS only, no effect on TLS.)
2436 *
2437 * \param conf SSL configuration
2438 * \param min Initial timeout value in milliseconds.
2439 * Default: 1000 (1 second).
2440 * \param max Maximum timeout value in milliseconds.
2441 * Default: 60000 (60 seconds).
2442 *
2443 * \note Default values are from RFC 6347 section 4.2.4.1.
2444 *
2445 * \note The 'min' value should typically be slightly above the
2446 * expected round-trip time to your peer, plus whatever time
2447 * it takes for the peer to process the message. For example,
2448 * if your RTT is about 600ms and you peer needs up to 1s to
2449 * do the cryptographic operations in the handshake, then you
2450 * should set 'min' slightly above 1600. Lower values of 'min'
2451 * might cause spurious resends which waste network resources,
2452 * while larger value of 'min' will increase overall latency
2453 * on unreliable network links.
2454 *
2455 * \note The more unreliable your network connection is, the larger
2456 * your max / min ratio needs to be in order to achieve
2457 * reliable handshakes.
2458 *
2459 * \note Messages are retransmitted up to log2(ceil(max/min)) times.
2460 * For example, if min = 1s and max = 5s, the retransmit plan
2461 * goes: send ... 1s -> resend ... 2s -> resend ... 4s ->
2462 * resend ... 5s -> give up and return a timeout error.
2463 */
2464void mbedtls_ssl_conf_handshake_timeout(mbedtls_ssl_config *conf, uint32_t min, uint32_t max);
2465#endif /* MBEDTLS_SSL_PROTO_DTLS */
2466
2467#if defined(MBEDTLS_SSL_SRV_C)
2468/**
2469 * \brief Set the session cache callbacks (server-side only)
2470 * If not set, no session resuming is done (except if session
2471 * tickets are enabled too).
2472 *
2473 * The session cache has the responsibility to check for stale
2474 * entries based on timeout. See RFC 5246 for recommendations.
2475 *
2476 * Warning: session.peer_cert is cleared by the SSL/TLS layer on
2477 * connection shutdown, so do not cache the pointer! Either set
2478 * it to NULL or make a full copy of the certificate.
2479 *
2480 * The get callback is called once during the initial handshake
2481 * to enable session resuming. The get function has the
2482 * following parameters: (void *parameter, mbedtls_ssl_session *session)
2483 * If a valid entry is found, it should fill the master of
2484 * the session object with the cached values and return 0,
2485 * return 1 otherwise. Optionally peer_cert can be set as well
2486 * if it is properly present in cache entry.
2487 *
2488 * The set callback is called once during the initial handshake
2489 * to enable session resuming after the entire handshake has
2490 * been finished. The set function has the following parameters:
2491 * (void *parameter, const mbedtls_ssl_session *session). The function
2492 * should create a cache entry for future retrieval based on
2493 * the data in the session structure and should keep in mind
2494 * that the mbedtls_ssl_session object presented (and all its referenced
2495 * data) is cleared by the SSL/TLS layer when the connection is
2496 * terminated. It is recommended to add metadata to determine if
2497 * an entry is still valid in the future. Return 0 if
2498 * successfully cached, return 1 otherwise.
2499 *
2500 * \param conf SSL configuration
2501 * \param p_cache parameter (context) for both callbacks
2502 * \param f_get_cache session get callback
2503 * \param f_set_cache session set callback
2504 */
2505void mbedtls_ssl_conf_session_cache(mbedtls_ssl_config *conf,
2506 void *p_cache,
2507 int (*f_get_cache)(void *, mbedtls_ssl_session *),
2508 int (*f_set_cache)(void *, const mbedtls_ssl_session *));
2509#endif /* MBEDTLS_SSL_SRV_C */
2510
2511#if defined(MBEDTLS_SSL_CLI_C)
2512/**
2513 * \brief Request resumption of session (client-side only)
2514 * Session data is copied from presented session structure.
2515 *
2516 * \param ssl SSL context
2517 * \param session session context
2518 *
2519 * \return 0 if successful,
2520 * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed,
2521 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or
2522 * arguments are otherwise invalid
2523 *
2524 * \sa mbedtls_ssl_get_session()
2525 */
2526int mbedtls_ssl_set_session(mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session);
2527#endif /* MBEDTLS_SSL_CLI_C */
2528
2529/**
2530 * \brief Load serialized session data into a session structure.
2531 * On client, this can be used for loading saved sessions
2532 * before resuming them with mbedtls_ssl_set_session().
2533 * On server, this can be used for alternative implementations
2534 * of session cache or session tickets.
2535 *
2536 * \warning If a peer certificate chain is associated with the session,
2537 * the serialized state will only contain the peer's
2538 * end-entity certificate and the result of the chain
2539 * verification (unless verification was disabled), but not
2540 * the rest of the chain.
2541 *
2542 * \see mbedtls_ssl_session_save()
2543 * \see mbedtls_ssl_set_session()
2544 *
2545 * \param session The session structure to be populated. It must have been
2546 * initialised with mbedtls_ssl_session_init() but not
2547 * populated yet.
2548 * \param buf The buffer holding the serialized session data. It must be a
2549 * readable buffer of at least \p len bytes.
2550 * \param len The size of the serialized data in bytes.
2551 *
2552 * \return \c 0 if successful.
2553 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
2554 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
2555 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
2556 * was generated in a different version or configuration of
2557 * Mbed TLS.
2558 * \return Another negative value for other kinds of errors (for
2559 * example, unsupported features in the embedded certificate).
2560 */
2561int mbedtls_ssl_session_load(mbedtls_ssl_session *session,
2562 const unsigned char *buf,
2563 size_t len);
2564
2565/**
2566 * \brief Save session structure as serialized data in a buffer.
2567 * On client, this can be used for saving session data,
2568 * potentially in non-volatile storage, for resuming later.
2569 * On server, this can be used for alternative implementations
2570 * of session cache or session tickets.
2571 *
2572 * \see mbedtls_ssl_session_load()
2573 * \see mbedtls_ssl_get_session_pointer()
2574 *
2575 * \param session The session structure to be saved.
2576 * \param buf The buffer to write the serialized data to. It must be a
2577 * writeable buffer of at least \p buf_len bytes, or may be \c
2578 * NULL if \p buf_len is \c 0.
2579 * \param buf_len The number of bytes available for writing in \p buf.
2580 * \param olen The size in bytes of the data that has been or would have
2581 * been written. It must point to a valid \c size_t.
2582 *
2583 * \note \p olen is updated to the correct value regardless of
2584 * whether \p buf_len was large enough. This makes it possible
2585 * to determine the necessary size by calling this function
2586 * with \p buf set to \c NULL and \p buf_len to \c 0.
2587 *
2588 * \return \c 0 if successful.
2589 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
2590 */
2591int mbedtls_ssl_session_save(const mbedtls_ssl_session *session,
2592 unsigned char *buf,
2593 size_t buf_len,
2594 size_t *olen);
2595
2596/**
2597 * \brief Get a pointer to the current session structure, for example
2598 * to serialize it.
2599 *
2600 * \warning Ownership of the session remains with the SSL context, and
2601 * the returned pointer is only guaranteed to be valid until
2602 * the next API call operating on the same \p ssl context.
2603 *
2604 * \see mbedtls_ssl_session_save()
2605 *
2606 * \param ssl The SSL context.
2607 *
2608 * \return A pointer to the current session if successful.
2609 * \return \c NULL if no session is active.
2610 */
2611const mbedtls_ssl_session *mbedtls_ssl_get_session_pointer(const mbedtls_ssl_context *ssl);
2612
2613/**
2614 * \brief Set the list of allowed ciphersuites and the preference
2615 * order. First in the list has the highest preference.
2616 * (Overrides all version-specific lists)
2617 *
2618 * The ciphersuites array is not copied, and must remain
2619 * valid for the lifetime of the ssl_config.
2620 *
2621 * Note: The server uses its own preferences
2622 * over the preference of the client unless
2623 * MBEDTLS_SSL_SRV_RESPECT_CLIENT_PREFERENCE is defined!
2624 *
2625 * \param conf SSL configuration
2626 * \param ciphersuites 0-terminated list of allowed ciphersuites
2627 */
2628void mbedtls_ssl_conf_ciphersuites(mbedtls_ssl_config *conf,
2629 const int *ciphersuites);
2630
2631#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
2632#define MBEDTLS_SSL_UNEXPECTED_CID_IGNORE 0
2633#define MBEDTLS_SSL_UNEXPECTED_CID_FAIL 1
2634/**
2635 * \brief Specify the length of Connection IDs for incoming
2636 * encrypted DTLS records, as well as the behaviour
2637 * on unexpected CIDs.
2638 *
2639 * By default, the CID length is set to \c 0,
2640 * and unexpected CIDs are silently ignored.
2641 *
2642 * \param conf The SSL configuration to modify.
2643 * \param len The length in Bytes of the CID fields in encrypted
2644 * DTLS records using the CID mechanism. This must
2645 * not be larger than #MBEDTLS_SSL_CID_OUT_LEN_MAX.
2646 * \param ignore_other_cids This determines the stack's behaviour when
2647 * receiving a record with an unexpected CID.
2648 * Possible values are:
2649 * - #MBEDTLS_SSL_UNEXPECTED_CID_IGNORE
2650 * In this case, the record is silently ignored.
2651 * - #MBEDTLS_SSL_UNEXPECTED_CID_FAIL
2652 * In this case, the stack fails with the specific
2653 * error code #MBEDTLS_ERR_SSL_UNEXPECTED_CID.
2654 *
2655 * \note The CID specification allows implementations to either
2656 * use a common length for all incoming connection IDs or
2657 * allow variable-length incoming IDs. Mbed TLS currently
2658 * requires a common length for all connections sharing the
2659 * same SSL configuration; this allows simpler parsing of
2660 * record headers.
2661 *
2662 * \return \c 0 on success.
2663 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if \p len
2664 * is too large.
2665 */
2666int mbedtls_ssl_conf_cid(mbedtls_ssl_config *conf, size_t len,
2667 int ignore_other_cids);
2668#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
2669
2670/**
2671 * \brief Set the list of allowed ciphersuites and the
2672 * preference order for a specific version of the protocol.
2673 * (Only useful on the server side)
2674 *
2675 * The ciphersuites array is not copied, and must remain
2676 * valid for the lifetime of the ssl_config.
2677 *
2678 * \param conf SSL configuration
2679 * \param ciphersuites 0-terminated list of allowed ciphersuites
2680 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3
2681 * supported)
2682 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
2683 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
2684 * MBEDTLS_SSL_MINOR_VERSION_3 supported)
2685 *
2686 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0
2687 * and MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
2688 */
2689void mbedtls_ssl_conf_ciphersuites_for_version(mbedtls_ssl_config *conf,
2690 const int *ciphersuites,
2691 int major, int minor);
2692
2693#if defined(MBEDTLS_X509_CRT_PARSE_C)
2694/**
2695 * \brief Set the X.509 security profile used for verification
2696 *
2697 * \note The restrictions are enforced for all certificates in the
2698 * chain. However, signatures in the handshake are not covered
2699 * by this setting but by \b mbedtls_ssl_conf_sig_hashes().
2700 *
2701 * \param conf SSL configuration
2702 * \param profile Profile to use
2703 */
2704void mbedtls_ssl_conf_cert_profile(mbedtls_ssl_config *conf,
2705 const mbedtls_x509_crt_profile *profile);
2706
2707/**
2708 * \brief Set the data required to verify peer certificate
2709 *
2710 * \note See \c mbedtls_x509_crt_verify() for notes regarding the
2711 * parameters ca_chain (maps to trust_ca for that function)
2712 * and ca_crl.
2713 *
2714 * \param conf SSL configuration
2715 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
2716 * \param ca_crl trusted CA CRLs
2717 */
2718void mbedtls_ssl_conf_ca_chain(mbedtls_ssl_config *conf,
2719 mbedtls_x509_crt *ca_chain,
2720 mbedtls_x509_crl *ca_crl);
2721
2722#if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
2723/**
2724 * \brief Set the trusted certificate callback.
2725 *
2726 * This API allows to register the set of trusted certificates
2727 * through a callback, instead of a linked list as configured
2728 * by mbedtls_ssl_conf_ca_chain().
2729 *
2730 * This is useful for example in contexts where a large number
2731 * of CAs are used, and the inefficiency of maintaining them
2732 * in a linked list cannot be tolerated. It is also useful when
2733 * the set of trusted CAs needs to be modified frequently.
2734 *
2735 * See the documentation of `mbedtls_x509_crt_ca_cb_t` for
2736 * more information.
2737 *
2738 * \param conf The SSL configuration to register the callback with.
2739 * \param f_ca_cb The trusted certificate callback to use when verifying
2740 * certificate chains.
2741 * \param p_ca_cb The context to be passed to \p f_ca_cb (for example,
2742 * a reference to a trusted CA database).
2743 *
2744 * \note This API is incompatible with mbedtls_ssl_conf_ca_chain():
2745 * Any call to this function overwrites the values set through
2746 * earlier calls to mbedtls_ssl_conf_ca_chain() or
2747 * mbedtls_ssl_conf_ca_cb().
2748 *
2749 * \note This API is incompatible with CA indication in
2750 * CertificateRequest messages: A server-side SSL context which
2751 * is bound to an SSL configuration that uses a CA callback
2752 * configured via mbedtls_ssl_conf_ca_cb(), and which requires
2753 * client authentication, will send an empty CA list in the
2754 * corresponding CertificateRequest message.
2755 *
2756 * \note This API is incompatible with mbedtls_ssl_set_hs_ca_chain():
2757 * If an SSL context is bound to an SSL configuration which uses
2758 * CA callbacks configured via mbedtls_ssl_conf_ca_cb(), then
2759 * calls to mbedtls_ssl_set_hs_ca_chain() have no effect.
2760 *
2761 * \note The use of this API disables the use of restartable ECC
2762 * during X.509 CRT signature verification (but doesn't affect
2763 * other uses).
2764 *
2765 * \warning This API is incompatible with the use of CRLs. Any call to
2766 * mbedtls_ssl_conf_ca_cb() unsets CRLs configured through
2767 * earlier calls to mbedtls_ssl_conf_ca_chain().
2768 *
2769 * \warning In multi-threaded environments, the callback \p f_ca_cb
2770 * must be thread-safe, and it is the user's responsibility
2771 * to guarantee this (for example through a mutex
2772 * contained in the callback context pointed to by \p p_ca_cb).
2773 */
2774void mbedtls_ssl_conf_ca_cb(mbedtls_ssl_config *conf,
2775 mbedtls_x509_crt_ca_cb_t f_ca_cb,
2776 void *p_ca_cb);
2777#endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
2778
2779/**
2780 * \brief Set own certificate chain and private key
2781 *
2782 * \note own_cert should contain in order from the bottom up your
2783 * certificate chain. The top certificate (self-signed)
2784 * can be omitted.
2785 *
2786 * \note On server, this function can be called multiple times to
2787 * provision more than one cert/key pair (eg one ECDSA, one
2788 * RSA with SHA-256, one RSA with SHA-1). An adequate
2789 * certificate will be selected according to the client's
2790 * advertised capabilities. In case multiple certificates are
2791 * adequate, preference is given to the one set by the first
2792 * call to this function, then second, etc.
2793 *
2794 * \note On client, only the first call has any effect. That is,
2795 * only one client certificate can be provisioned. The
2796 * server's preferences in its CertificateRequest message will
2797 * be ignored and our only cert will be sent regardless of
2798 * whether it matches those preferences - the server can then
2799 * decide what it wants to do with it.
2800 *
2801 * \note The provided \p pk_key needs to match the public key in the
2802 * first certificate in \p own_cert, or all handshakes using
2803 * that certificate will fail. It is your responsibility
2804 * to ensure that; this function will not perform any check.
2805 * You may use mbedtls_pk_check_pair() in order to perform
2806 * this check yourself, but be aware that this function can
2807 * be computationally expensive on some key types.
2808 *
2809 * \param conf SSL configuration
2810 * \param own_cert own public certificate chain
2811 * \param pk_key own private key
2812 *
2813 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
2814 */
2815int mbedtls_ssl_conf_own_cert(mbedtls_ssl_config *conf,
2816 mbedtls_x509_crt *own_cert,
2817 mbedtls_pk_context *pk_key);
2818#endif /* MBEDTLS_X509_CRT_PARSE_C */
2819
2820#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
2821/**
2822 * \brief Configure a pre-shared key (PSK) and identity
2823 * to be used in PSK-based ciphersuites.
2824 *
2825 * \note This is mainly useful for clients. Servers will usually
2826 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
2827 *
2828 * \note A PSK set by \c mbedtls_ssl_set_hs_psk() in the PSK callback
2829 * takes precedence over a PSK configured by this function.
2830 *
2831 * \warning Currently, clients can only register a single pre-shared key.
2832 * Calling this function or mbedtls_ssl_conf_psk_opaque() more
2833 * than once will overwrite values configured in previous calls.
2834 * Support for setting multiple PSKs on clients and selecting
2835 * one based on the identity hint is not a planned feature,
2836 * but feedback is welcomed.
2837 *
2838 * \param conf The SSL configuration to register the PSK with.
2839 * \param psk The pointer to the pre-shared key to use.
2840 * \param psk_len The length of the pre-shared key in bytes.
2841 * \param psk_identity The pointer to the pre-shared key identity.
2842 * \param psk_identity_len The length of the pre-shared key identity
2843 * in bytes.
2844 *
2845 * \note The PSK and its identity are copied internally and
2846 * hence need not be preserved by the caller for the lifetime
2847 * of the SSL configuration.
2848 *
2849 * \return \c 0 if successful.
2850 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
2851 */
2852int mbedtls_ssl_conf_psk(mbedtls_ssl_config *conf,
2853 const unsigned char *psk, size_t psk_len,
2854 const unsigned char *psk_identity, size_t psk_identity_len);
2855
2856#if defined(MBEDTLS_USE_PSA_CRYPTO)
2857/**
2858 * \brief Configure an opaque pre-shared key (PSK) and identity
2859 * to be used in PSK-based ciphersuites.
2860 *
2861 * \note This is mainly useful for clients. Servers will usually
2862 * want to use \c mbedtls_ssl_conf_psk_cb() instead.
2863 *
2864 * \note An opaque PSK set by \c mbedtls_ssl_set_hs_psk_opaque() in
2865 * the PSK callback takes precedence over an opaque PSK
2866 * configured by this function.
2867 *
2868 * \warning Currently, clients can only register a single pre-shared key.
2869 * Calling this function or mbedtls_ssl_conf_psk() more than
2870 * once will overwrite values configured in previous calls.
2871 * Support for setting multiple PSKs on clients and selecting
2872 * one based on the identity hint is not a planned feature,
2873 * but feedback is welcomed.
2874 *
2875 * \param conf The SSL configuration to register the PSK with.
2876 * \param psk The identifier of the key slot holding the PSK.
2877 * Until \p conf is destroyed or this function is successfully
2878 * called again, the key slot \p psk must be populated with a
2879 * key of type PSA_ALG_CATEGORY_KEY_DERIVATION whose policy
2880 * allows its use for the key derivation algorithm applied
2881 * in the handshake.
2882 * \param psk_identity The pointer to the pre-shared key identity.
2883 * \param psk_identity_len The length of the pre-shared key identity
2884 * in bytes.
2885 *
2886 * \note The PSK identity hint is copied internally and hence need
2887 * not be preserved by the caller for the lifetime of the
2888 * SSL configuration.
2889 *
2890 * \return \c 0 if successful.
2891 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
2892 */
2893int mbedtls_ssl_conf_psk_opaque(mbedtls_ssl_config *conf,
2894 psa_key_id_t psk,
2895 const unsigned char *psk_identity,
2896 size_t psk_identity_len);
2897#endif /* MBEDTLS_USE_PSA_CRYPTO */
2898
2899/**
2900 * \brief Set the pre-shared Key (PSK) for the current handshake.
2901 *
2902 * \note This should only be called inside the PSK callback,
2903 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
2904 *
2905 * \note A PSK set by this function takes precedence over a PSK
2906 * configured by \c mbedtls_ssl_conf_psk().
2907 *
2908 * \param ssl The SSL context to configure a PSK for.
2909 * \param psk The pointer to the pre-shared key.
2910 * \param psk_len The length of the pre-shared key in bytes.
2911 *
2912 * \return \c 0 if successful.
2913 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
2914 */
2915int mbedtls_ssl_set_hs_psk(mbedtls_ssl_context *ssl,
2916 const unsigned char *psk, size_t psk_len);
2917
2918#if defined(MBEDTLS_USE_PSA_CRYPTO)
2919/**
2920 * \brief Set an opaque pre-shared Key (PSK) for the current handshake.
2921 *
2922 * \note This should only be called inside the PSK callback,
2923 * i.e. the function passed to \c mbedtls_ssl_conf_psk_cb().
2924 *
2925 * \note An opaque PSK set by this function takes precedence over an
2926 * opaque PSK configured by \c mbedtls_ssl_conf_psk_opaque().
2927 *
2928 * \param ssl The SSL context to configure a PSK for.
2929 * \param psk The identifier of the key slot holding the PSK.
2930 * For the duration of the current handshake, the key slot
2931 * must be populated with a key of type
2932 * PSA_ALG_CATEGORY_KEY_DERIVATION whose policy allows its
2933 * use for the key derivation algorithm
2934 * applied in the handshake.
2935 *
2936 * \return \c 0 if successful.
2937 * \return An \c MBEDTLS_ERR_SSL_XXX error code on failure.
2938 */
2939int mbedtls_ssl_set_hs_psk_opaque(mbedtls_ssl_context *ssl,
2940 psa_key_id_t psk);
2941#endif /* MBEDTLS_USE_PSA_CRYPTO */
2942
2943/**
2944 * \brief Set the PSK callback (server-side only).
2945 *
2946 * If set, the PSK callback is called for each
2947 * handshake where a PSK-based ciphersuite was negotiated.
2948 * The caller provides the identity received and wants to
2949 * receive the actual PSK data and length.
2950 *
2951 * The callback has the following parameters:
2952 * - \c void*: The opaque pointer \p p_psk.
2953 * - \c mbedtls_ssl_context*: The SSL context to which
2954 * the operation applies.
2955 * - \c const unsigned char*: The PSK identity
2956 * selected by the client.
2957 * - \c size_t: The length of the PSK identity
2958 * selected by the client.
2959 *
2960 * If a valid PSK identity is found, the callback should use
2961 * \c mbedtls_ssl_set_hs_psk() or
2962 * \c mbedtls_ssl_set_hs_psk_opaque()
2963 * on the SSL context to set the correct PSK and return \c 0.
2964 * Any other return value will result in a denied PSK identity.
2965 *
2966 * \note A dynamic PSK (i.e. set by the PSK callback) takes
2967 * precedence over a static PSK (i.e. set by
2968 * \c mbedtls_ssl_conf_psk() or
2969 * \c mbedtls_ssl_conf_psk_opaque()).
2970 * This means that if you set a PSK callback using this
2971 * function, you don't need to set a PSK using
2972 * \c mbedtls_ssl_conf_psk() or
2973 * \c mbedtls_ssl_conf_psk_opaque()).
2974 *
2975 * \param conf The SSL configuration to register the callback with.
2976 * \param f_psk The callback for selecting and setting the PSK based
2977 * in the PSK identity chosen by the client.
2978 * \param p_psk A pointer to an opaque structure to be passed to
2979 * the callback, for example a PSK store.
2980 */
2981void mbedtls_ssl_conf_psk_cb(mbedtls_ssl_config *conf,
2982 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *,
2983 size_t),
2984 void *p_psk);
2985#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
2986
2987#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
2988
2989#if !defined(MBEDTLS_DEPRECATED_REMOVED)
2990
2991#if defined(MBEDTLS_DEPRECATED_WARNING)
2992#define MBEDTLS_DEPRECATED __attribute__((deprecated))
2993#else
2994#define MBEDTLS_DEPRECATED
2995#endif
2996
2997/**
2998 * \brief Set the Diffie-Hellman public P and G values,
2999 * read as hexadecimal strings (server-side only)
3000 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG])
3001 *
3002 * \param conf SSL configuration
3003 * \param dhm_P Diffie-Hellman-Merkle modulus
3004 * \param dhm_G Diffie-Hellman-Merkle generator
3005 *
3006 * \deprecated Superseded by \c mbedtls_ssl_conf_dh_param_bin.
3007 *
3008 * \return 0 if successful
3009 */
3010MBEDTLS_DEPRECATED int mbedtls_ssl_conf_dh_param(mbedtls_ssl_config *conf,
3011 const char *dhm_P,
3012 const char *dhm_G);
3013
3014#endif /* MBEDTLS_DEPRECATED_REMOVED */
3015
3016/**
3017 * \brief Set the Diffie-Hellman public P and G values
3018 * from big-endian binary presentations.
3019 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN)
3020 *
3021 * \param conf SSL configuration
3022 * \param dhm_P Diffie-Hellman-Merkle modulus in big-endian binary form
3023 * \param P_len Length of DHM modulus
3024 * \param dhm_G Diffie-Hellman-Merkle generator in big-endian binary form
3025 * \param G_len Length of DHM generator
3026 *
3027 * \return 0 if successful
3028 */
3029int mbedtls_ssl_conf_dh_param_bin(mbedtls_ssl_config *conf,
3030 const unsigned char *dhm_P, size_t P_len,
3031 const unsigned char *dhm_G, size_t G_len);
3032
3033/**
3034 * \brief Set the Diffie-Hellman public P and G values,
3035 * read from existing context (server-side only)
3036 *
3037 * \param conf SSL configuration
3038 * \param dhm_ctx Diffie-Hellman-Merkle context
3039 *
3040 * \return 0 if successful
3041 */
3042int mbedtls_ssl_conf_dh_param_ctx(mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx);
3043#endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */
3044
3045#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
3046/**
3047 * \brief Set the minimum length for Diffie-Hellman parameters.
3048 * (Client-side only.)
3049 * (Default: 1024 bits.)
3050 *
3051 * \param conf SSL configuration
3052 * \param bitlen Minimum bit length of the DHM prime
3053 */
3054void mbedtls_ssl_conf_dhm_min_bitlen(mbedtls_ssl_config *conf,
3055 unsigned int bitlen);
3056#endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */
3057
3058#if defined(MBEDTLS_ECP_C)
3059/**
3060 * \brief Set the allowed curves in order of preference.
3061 * (Default: all defined curves in order of decreasing size,
3062 * except that Montgomery curves come last. This order
3063 * is likely to change in a future version.)
3064 *
3065 * On server: this only affects selection of the ECDHE curve;
3066 * the curves used for ECDH and ECDSA are determined by the
3067 * list of available certificates instead.
3068 *
3069 * On client: this affects the list of curves offered for any
3070 * use. The server can override our preference order.
3071 *
3072 * Both sides: limits the set of curves accepted for use in
3073 * ECDHE and in the peer's end-entity certificate.
3074 *
3075 * \note This has no influence on which curves are allowed inside the
3076 * certificate chains, see \c mbedtls_ssl_conf_cert_profile()
3077 * for that. For the end-entity certificate however, the key
3078 * will be accepted only if it is allowed both by this list
3079 * and by the cert profile.
3080 *
3081 * \note This list should be ordered by decreasing preference
3082 * (preferred curve first).
3083 *
3084 * \param conf SSL configuration
3085 * \param curves Ordered list of allowed curves,
3086 * terminated by MBEDTLS_ECP_DP_NONE.
3087 */
3088void mbedtls_ssl_conf_curves(mbedtls_ssl_config *conf,
3089 const mbedtls_ecp_group_id *curves);
3090#endif /* MBEDTLS_ECP_C */
3091
3092#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
3093/**
3094 * \brief Set the allowed hashes for signatures during the handshake.
3095 * (Default: all SHA-2 hashes, largest first. Also SHA-1 if
3096 * the compile-time option
3097 * `MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE` is enabled.)
3098 *
3099 * \note This only affects which hashes are offered and can be used
3100 * for signatures during the handshake. Hashes for message
3101 * authentication and the TLS PRF are controlled by the
3102 * ciphersuite, see \c mbedtls_ssl_conf_ciphersuites(). Hashes
3103 * used for certificate signature are controlled by the
3104 * verification profile, see \c mbedtls_ssl_conf_cert_profile().
3105 *
3106 * \note This list should be ordered by decreasing preference
3107 * (preferred hash first).
3108 *
3109 * \param conf SSL configuration
3110 * \param hashes Ordered list of allowed signature hashes,
3111 * terminated by \c MBEDTLS_MD_NONE.
3112 */
3113void mbedtls_ssl_conf_sig_hashes(mbedtls_ssl_config *conf,
3114 const int *hashes);
3115#endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
3116
3117#if defined(MBEDTLS_X509_CRT_PARSE_C)
3118/**
3119 * \brief Set or reset the hostname to check against the received
3120 * server certificate. It sets the ServerName TLS extension,
3121 * too, if that extension is enabled. (client-side only)
3122 *
3123 * \param ssl SSL context
3124 * \param hostname the server hostname, may be NULL to clear hostname
3125
3126 * \note Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN.
3127 *
3128 * \return 0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on
3129 * allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on
3130 * too long input hostname.
3131 *
3132 * Hostname set to the one provided on success (cleared
3133 * when NULL). On allocation failure hostname is cleared.
3134 * On too long input failure, old hostname is unchanged.
3135 */
3136int mbedtls_ssl_set_hostname(mbedtls_ssl_context *ssl, const char *hostname);
3137#endif /* MBEDTLS_X509_CRT_PARSE_C */
3138
3139#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
3140/**
3141 * \brief Set own certificate and key for the current handshake
3142 *
3143 * \note Same as \c mbedtls_ssl_conf_own_cert() but for use within
3144 * the SNI callback.
3145 *
3146 * \param ssl SSL context
3147 * \param own_cert own public certificate chain
3148 * \param pk_key own private key
3149 *
3150 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
3151 */
3152int mbedtls_ssl_set_hs_own_cert(mbedtls_ssl_context *ssl,
3153 mbedtls_x509_crt *own_cert,
3154 mbedtls_pk_context *pk_key);
3155
3156/**
3157 * \brief Set the data required to verify peer certificate for the
3158 * current handshake
3159 *
3160 * \note Same as \c mbedtls_ssl_conf_ca_chain() but for use within
3161 * the SNI callback.
3162 *
3163 * \param ssl SSL context
3164 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
3165 * \param ca_crl trusted CA CRLs
3166 */
3167void mbedtls_ssl_set_hs_ca_chain(mbedtls_ssl_context *ssl,
3168 mbedtls_x509_crt *ca_chain,
3169 mbedtls_x509_crl *ca_crl);
3170
3171/**
3172 * \brief Set authmode for the current handshake.
3173 *
3174 * \note Same as \c mbedtls_ssl_conf_authmode() but for use within
3175 * the SNI callback.
3176 *
3177 * \param ssl SSL context
3178 * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or
3179 * MBEDTLS_SSL_VERIFY_REQUIRED
3180 */
3181void mbedtls_ssl_set_hs_authmode(mbedtls_ssl_context *ssl,
3182 int authmode);
3183
3184/**
3185 * \brief Set server side ServerName TLS extension callback
3186 * (optional, server-side only).
3187 *
3188 * If set, the ServerName callback is called whenever the
3189 * server receives a ServerName TLS extension from the client
3190 * during a handshake. The ServerName callback has the
3191 * following parameters: (void *parameter, mbedtls_ssl_context *ssl,
3192 * const unsigned char *hostname, size_t len). If a suitable
3193 * certificate is found, the callback must set the
3194 * certificate(s) and key(s) to use with \c
3195 * mbedtls_ssl_set_hs_own_cert() (can be called repeatedly),
3196 * and may optionally adjust the CA and associated CRL with \c
3197 * mbedtls_ssl_set_hs_ca_chain() as well as the client
3198 * authentication mode with \c mbedtls_ssl_set_hs_authmode(),
3199 * then must return 0. If no matching name is found, the
3200 * callback must either set a default cert, or
3201 * return non-zero to abort the handshake at this point.
3202 *
3203 * \param conf SSL configuration
3204 * \param f_sni verification function
3205 * \param p_sni verification parameter
3206 */
3207void mbedtls_ssl_conf_sni(mbedtls_ssl_config *conf,
3208 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *,
3209 size_t),
3210 void *p_sni);
3211#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
3212
3213#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
3214/**
3215 * \brief Set the EC J-PAKE password for current handshake.
3216 *
3217 * \note An internal copy is made, and destroyed as soon as the
3218 * handshake is completed, or when the SSL context is reset or
3219 * freed.
3220 *
3221 * \note The SSL context needs to be already set up. The right place
3222 * to call this function is between \c mbedtls_ssl_setup() or
3223 * \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake().
3224 *
3225 * \param ssl SSL context
3226 * \param pw EC J-PAKE password (pre-shared secret)
3227 * \param pw_len length of pw in bytes
3228 *
3229 * \return 0 on success, or a negative error code.
3230 */
3231int mbedtls_ssl_set_hs_ecjpake_password(mbedtls_ssl_context *ssl,
3232 const unsigned char *pw,
3233 size_t pw_len);
3234#endif /*MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
3235
3236#if defined(MBEDTLS_SSL_ALPN)
3237/**
3238 * \brief Set the supported Application Layer Protocols.
3239 *
3240 * \param conf SSL configuration
3241 * \param protos Pointer to a NULL-terminated list of supported protocols,
3242 * in decreasing preference order. The pointer to the list is
3243 * recorded by the library for later reference as required, so
3244 * the lifetime of the table must be at least as long as the
3245 * lifetime of the SSL configuration structure.
3246 *
3247 * \return 0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA.
3248 */
3249int mbedtls_ssl_conf_alpn_protocols(mbedtls_ssl_config *conf, const char **protos);
3250
3251/**
3252 * \brief Get the name of the negotiated Application Layer Protocol.
3253 * This function should be called after the handshake is
3254 * completed.
3255 *
3256 * \param ssl SSL context
3257 *
3258 * \return Protocol name, or NULL if no protocol was negotiated.
3259 */
3260const char *mbedtls_ssl_get_alpn_protocol(const mbedtls_ssl_context *ssl);
3261#endif /* MBEDTLS_SSL_ALPN */
3262
3263#if defined(MBEDTLS_SSL_DTLS_SRTP)
3264#if defined(MBEDTLS_DEBUG_C)
3265static inline const char *mbedtls_ssl_get_srtp_profile_as_string(mbedtls_ssl_srtp_profile profile)
3266{
3267 switch (profile) {
3268 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80:
3269 return "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80";
3270 case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32:
3271 return "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32";
3272 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80:
3273 return "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80";
3274 case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32:
3275 return "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32";
3276 default: break;
3277 }
3278 return "";
3279}
3280#endif /* MBEDTLS_DEBUG_C */
3281/**
3282 * \brief Manage support for mki(master key id) value
3283 * in use_srtp extension.
3284 * MKI is an optional part of SRTP used for key management
3285 * and re-keying. See RFC3711 section 3.1 for details.
3286 * The default value is
3287 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED.
3288 *
3289 * \param conf The SSL configuration to manage mki support.
3290 * \param support_mki_value Enable or disable mki usage. Values are
3291 * #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED
3292 * or #MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED.
3293 */
3294void mbedtls_ssl_conf_srtp_mki_value_supported(mbedtls_ssl_config *conf,
3295 int support_mki_value);
3296
3297/**
3298 * \brief Set the supported DTLS-SRTP protection profiles.
3299 *
3300 * \param conf SSL configuration
3301 * \param profiles Pointer to a List of MBEDTLS_TLS_SRTP_UNSET terminated
3302 * supported protection profiles
3303 * in decreasing preference order.
3304 * The pointer to the list is recorded by the library
3305 * for later reference as required, so the lifetime
3306 * of the table must be at least as long as the lifetime
3307 * of the SSL configuration structure.
3308 * The list must not hold more than
3309 * MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH elements
3310 * (excluding the terminating MBEDTLS_TLS_SRTP_UNSET).
3311 *
3312 * \return 0 on success
3313 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA when the list of
3314 * protection profiles is incorrect.
3315 */
3316int mbedtls_ssl_conf_dtls_srtp_protection_profiles
3317 (mbedtls_ssl_config *conf,
3318 const mbedtls_ssl_srtp_profile *profiles);
3319
3320/**
3321 * \brief Set the mki_value for the current DTLS-SRTP session.
3322 *
3323 * \param ssl SSL context to use.
3324 * \param mki_value The MKI value to set.
3325 * \param mki_len The length of the MKI value.
3326 *
3327 * \note This function is relevant on client side only.
3328 * The server discovers the mki value during handshake.
3329 * A mki value set on server side using this function
3330 * is ignored.
3331 *
3332 * \return 0 on success
3333 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA
3334 * \return #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE
3335 */
3336int mbedtls_ssl_dtls_srtp_set_mki_value(mbedtls_ssl_context *ssl,
3337 unsigned char *mki_value,
3338 uint16_t mki_len);
3339/**
3340 * \brief Get the negotiated DTLS-SRTP information:
3341 * Protection profile and MKI value.
3342 *
3343 * \warning This function must be called after the handshake is
3344 * completed. The value returned by this function must
3345 * not be trusted or acted upon before the handshake completes.
3346 *
3347 * \param ssl The SSL context to query.
3348 * \param dtls_srtp_info The negotiated DTLS-SRTP information:
3349 * - Protection profile in use.
3350 * A direct mapping of the iana defined value for protection
3351 * profile on an uint16_t.
3352 http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
3353 * #MBEDTLS_TLS_SRTP_UNSET if the use of SRTP was not negotiated
3354 * or peer's Hello packet was not parsed yet.
3355 * - mki size and value( if size is > 0 ).
3356 */
3357void mbedtls_ssl_get_dtls_srtp_negotiation_result(const mbedtls_ssl_context *ssl,
3358 mbedtls_dtls_srtp_info *dtls_srtp_info);
3359#endif /* MBEDTLS_SSL_DTLS_SRTP */
3360
3361/**
3362 * \brief Set the maximum supported version sent from the client side
3363 * and/or accepted at the server side
3364 * (Default: MBEDTLS_SSL_MAX_MAJOR_VERSION, MBEDTLS_SSL_MAX_MINOR_VERSION)
3365 *
3366 * \note This ignores ciphersuites from higher versions.
3367 *
3368 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and
3369 * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
3370 *
3371 * \param conf SSL configuration
3372 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
3373 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
3374 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
3375 * MBEDTLS_SSL_MINOR_VERSION_3 supported)
3376 */
3377void mbedtls_ssl_conf_max_version(mbedtls_ssl_config *conf, int major, int minor);
3378
3379/**
3380 * \brief Set the minimum accepted SSL/TLS protocol version
3381 * (Default: TLS 1.0)
3382 *
3383 * \note Input outside of the SSL_MAX_XXXXX_VERSION and
3384 * SSL_MIN_XXXXX_VERSION range is ignored.
3385 *
3386 * \note MBEDTLS_SSL_MINOR_VERSION_0 (SSL v3) should be avoided.
3387 *
3388 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and
3389 * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
3390 *
3391 * \param conf SSL configuration
3392 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
3393 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
3394 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
3395 * MBEDTLS_SSL_MINOR_VERSION_3 supported)
3396 */
3397void mbedtls_ssl_conf_min_version(mbedtls_ssl_config *conf, int major, int minor);
3398
3399#if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C)
3400/**
3401 * \brief Set the fallback flag (client-side only).
3402 * (Default: MBEDTLS_SSL_IS_NOT_FALLBACK).
3403 *
3404 * \note Set to MBEDTLS_SSL_IS_FALLBACK when preparing a fallback
3405 * connection, that is a connection with max_version set to a
3406 * lower value than the value you're willing to use. Such
3407 * fallback connections are not recommended but are sometimes
3408 * necessary to interoperate with buggy (version-intolerant)
3409 * servers.
3410 *
3411 * \warning You should NOT set this to MBEDTLS_SSL_IS_FALLBACK for
3412 * non-fallback connections! This would appear to work for a
3413 * while, then cause failures when the server is upgraded to
3414 * support a newer TLS version.
3415 *
3416 * \param conf SSL configuration
3417 * \param fallback MBEDTLS_SSL_IS_NOT_FALLBACK or MBEDTLS_SSL_IS_FALLBACK
3418 */
3419void mbedtls_ssl_conf_fallback(mbedtls_ssl_config *conf, char fallback);
3420#endif /* MBEDTLS_SSL_FALLBACK_SCSV && MBEDTLS_SSL_CLI_C */
3421
3422#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
3423/**
3424 * \brief Enable or disable Encrypt-then-MAC
3425 * (Default: MBEDTLS_SSL_ETM_ENABLED)
3426 *
3427 * \note This should always be enabled, it is a security
3428 * improvement, and should not cause any interoperability
3429 * issue (used only if the peer supports it too).
3430 *
3431 * \param conf SSL configuration
3432 * \param etm MBEDTLS_SSL_ETM_ENABLED or MBEDTLS_SSL_ETM_DISABLED
3433 */
3434void mbedtls_ssl_conf_encrypt_then_mac(mbedtls_ssl_config *conf, char etm);
3435#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
3436
3437#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
3438/**
3439 * \brief Enable or disable Extended Master Secret negotiation.
3440 * (Default: MBEDTLS_SSL_EXTENDED_MS_ENABLED)
3441 *
3442 * \note This should always be enabled, it is a security fix to the
3443 * protocol, and should not cause any interoperability issue
3444 * (used only if the peer supports it too).
3445 *
3446 * \param conf SSL configuration
3447 * \param ems MBEDTLS_SSL_EXTENDED_MS_ENABLED or MBEDTLS_SSL_EXTENDED_MS_DISABLED
3448 */
3449void mbedtls_ssl_conf_extended_master_secret(mbedtls_ssl_config *conf, char ems);
3450#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
3451
3452#if defined(MBEDTLS_ARC4_C)
3453/**
3454 * \brief Disable or enable support for RC4
3455 * (Default: MBEDTLS_SSL_ARC4_DISABLED)
3456 *
3457 * \warning Use of RC4 in DTLS/TLS has been prohibited by RFC 7465
3458 * for security reasons. Use at your own risk.
3459 *
3460 * \note This function is deprecated and will be removed in
3461 * a future version of the library.
3462 * RC4 is disabled by default at compile time and needs to be
3463 * actively enabled for use with legacy systems.
3464 *
3465 * \param conf SSL configuration
3466 * \param arc4 MBEDTLS_SSL_ARC4_ENABLED or MBEDTLS_SSL_ARC4_DISABLED
3467 */
3468void mbedtls_ssl_conf_arc4_support(mbedtls_ssl_config *conf, char arc4);
3469#endif /* MBEDTLS_ARC4_C */
3470
3471#if defined(MBEDTLS_SSL_SRV_C)
3472/**
3473 * \brief Whether to send a list of acceptable CAs in
3474 * CertificateRequest messages.
3475 * (Default: do send)
3476 *
3477 * \param conf SSL configuration
3478 * \param cert_req_ca_list MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or
3479 * MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED
3480 */
3481void mbedtls_ssl_conf_cert_req_ca_list(mbedtls_ssl_config *conf,
3482 char cert_req_ca_list);
3483#endif /* MBEDTLS_SSL_SRV_C */
3484
3485#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
3486/**
3487 * \brief Set the maximum fragment length to emit and/or negotiate.
3488 * (Typical: the smaller of #MBEDTLS_SSL_IN_CONTENT_LEN and
3489 * #MBEDTLS_SSL_OUT_CONTENT_LEN, usually `2^14` bytes)
3490 * (Server: set maximum fragment length to emit,
3491 * usually negotiated by the client during handshake)
3492 * (Client: set maximum fragment length to emit *and*
3493 * negotiate with the server during handshake)
3494 * (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE)
3495 *
3496 * \note On the client side, the maximum fragment length extension
3497 * *will not* be used, unless the maximum fragment length has
3498 * been set via this function to a value different than
3499 * #MBEDTLS_SSL_MAX_FRAG_LEN_NONE.
3500 *
3501 * \note With TLS, this currently only affects ApplicationData (sent
3502 * with \c mbedtls_ssl_read()), not handshake messages.
3503 * With DTLS, this affects both ApplicationData and handshake.
3504 *
3505 * \note This sets the maximum length for a record's payload,
3506 * excluding record overhead that will be added to it, see
3507 * \c mbedtls_ssl_get_record_expansion().
3508 *
3509 * \note For DTLS, it is also possible to set a limit for the total
3510 * size of datagrams passed to the transport layer, including
3511 * record overhead, see \c mbedtls_ssl_set_mtu().
3512 *
3513 * \param conf SSL configuration
3514 * \param mfl_code Code for maximum fragment length (allowed values:
3515 * MBEDTLS_SSL_MAX_FRAG_LEN_512, MBEDTLS_SSL_MAX_FRAG_LEN_1024,
3516 * MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096)
3517 *
3518 * \return 0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA
3519 */
3520int mbedtls_ssl_conf_max_frag_len(mbedtls_ssl_config *conf, unsigned char mfl_code);
3521#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
3522
3523#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
3524/**
3525 * \brief Activate negotiation of truncated HMAC
3526 * (Default: MBEDTLS_SSL_TRUNC_HMAC_DISABLED)
3527 *
3528 * \param conf SSL configuration
3529 * \param truncate Enable or disable (MBEDTLS_SSL_TRUNC_HMAC_ENABLED or
3530 * MBEDTLS_SSL_TRUNC_HMAC_DISABLED)
3531 */
3532void mbedtls_ssl_conf_truncated_hmac(mbedtls_ssl_config *conf, int truncate);
3533#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
3534
3535#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
3536/**
3537 * \brief Enable / Disable 1/n-1 record splitting
3538 * (Default: MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED)
3539 *
3540 * \note Only affects SSLv3 and TLS 1.0, not higher versions.
3541 * Does not affect non-CBC ciphersuites in any version.
3542 *
3543 * \param conf SSL configuration
3544 * \param split MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED or
3545 * MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED
3546 */
3547void mbedtls_ssl_conf_cbc_record_splitting(mbedtls_ssl_config *conf, char split);
3548#endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */
3549
3550#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
3551/**
3552 * \brief Enable / Disable session tickets (client only).
3553 * (Default: MBEDTLS_SSL_SESSION_TICKETS_ENABLED.)
3554 *
3555 * \note On server, use \c mbedtls_ssl_conf_session_tickets_cb().
3556 *
3557 * \param conf SSL configuration
3558 * \param use_tickets Enable or disable (MBEDTLS_SSL_SESSION_TICKETS_ENABLED or
3559 * MBEDTLS_SSL_SESSION_TICKETS_DISABLED)
3560 */
3561void mbedtls_ssl_conf_session_tickets(mbedtls_ssl_config *conf, int use_tickets);
3562#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
3563
3564#if defined(MBEDTLS_SSL_RENEGOTIATION)
3565/**
3566 * \brief Enable / Disable renegotiation support for connection when
3567 * initiated by peer
3568 * (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED)
3569 *
3570 * \warning It is recommended to always disable renegotiation unless you
3571 * know you need it and you know what you're doing. In the
3572 * past, there have been several issues associated with
3573 * renegotiation or a poor understanding of its properties.
3574 *
3575 * \note Server-side, enabling renegotiation also makes the server
3576 * susceptible to a resource DoS by a malicious client.
3577 *
3578 * \param conf SSL configuration
3579 * \param renegotiation Enable or disable (MBEDTLS_SSL_RENEGOTIATION_ENABLED or
3580 * MBEDTLS_SSL_RENEGOTIATION_DISABLED)
3581 */
3582void mbedtls_ssl_conf_renegotiation(mbedtls_ssl_config *conf, int renegotiation);
3583#endif /* MBEDTLS_SSL_RENEGOTIATION */
3584
3585/**
3586 * \brief Prevent or allow legacy renegotiation.
3587 * (Default: MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION)
3588 *
3589 * MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION allows connections to
3590 * be established even if the peer does not support
3591 * secure renegotiation, but does not allow renegotiation
3592 * to take place if not secure.
3593 * (Interoperable and secure option)
3594 *
3595 * MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION allows renegotiations
3596 * with non-upgraded peers. Allowing legacy renegotiation
3597 * makes the connection vulnerable to specific man in the
3598 * middle attacks. (See RFC 5746)
3599 * (Most interoperable and least secure option)
3600 *
3601 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE breaks off connections
3602 * if peer does not support secure renegotiation. Results
3603 * in interoperability issues with non-upgraded peers
3604 * that do not support renegotiation altogether.
3605 * (Most secure option, interoperability issues)
3606 *
3607 * \param conf SSL configuration
3608 * \param allow_legacy Prevent or allow (SSL_NO_LEGACY_RENEGOTIATION,
3609 * SSL_ALLOW_LEGACY_RENEGOTIATION or
3610 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE)
3611 */
3612void mbedtls_ssl_conf_legacy_renegotiation(mbedtls_ssl_config *conf, int allow_legacy);
3613
3614#if defined(MBEDTLS_SSL_RENEGOTIATION)
3615/**
3616 * \brief Enforce renegotiation requests.
3617 * (Default: enforced, max_records = 16)
3618 *
3619 * When we request a renegotiation, the peer can comply or
3620 * ignore the request. This function allows us to decide
3621 * whether to enforce our renegotiation requests by closing
3622 * the connection if the peer doesn't comply.
3623 *
3624 * However, records could already be in transit from the peer
3625 * when the request is emitted. In order to increase
3626 * reliability, we can accept a number of records before the
3627 * expected handshake records.
3628 *
3629 * The optimal value is highly dependent on the specific usage
3630 * scenario.
3631 *
3632 * \note With DTLS and server-initiated renegotiation, the
3633 * HelloRequest is retransmitted every time mbedtls_ssl_read() times
3634 * out or receives Application Data, until:
3635 * - max_records records have beens seen, if it is >= 0, or
3636 * - the number of retransmits that would happen during an
3637 * actual handshake has been reached.
3638 * Please remember the request might be lost a few times
3639 * if you consider setting max_records to a really low value.
3640 *
3641 * \warning On client, the grace period can only happen during
3642 * mbedtls_ssl_read(), as opposed to mbedtls_ssl_write() and mbedtls_ssl_renegotiate()
3643 * which always behave as if max_record was 0. The reason is,
3644 * if we receive application data from the server, we need a
3645 * place to write it, which only happens during mbedtls_ssl_read().
3646 *
3647 * \param conf SSL configuration
3648 * \param max_records Use MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to
3649 * enforce renegotiation, or a non-negative value to enforce
3650 * it but allow for a grace period of max_records records.
3651 */
3652void mbedtls_ssl_conf_renegotiation_enforced(mbedtls_ssl_config *conf, int max_records);
3653
3654/**
3655 * \brief Set record counter threshold for periodic renegotiation.
3656 * (Default: 2^48 - 1)
3657 *
3658 * Renegotiation is automatically triggered when a record
3659 * counter (outgoing or incoming) crosses the defined
3660 * threshold. The default value is meant to prevent the
3661 * connection from being closed when the counter is about to
3662 * reached its maximal value (it is not allowed to wrap).
3663 *
3664 * Lower values can be used to enforce policies such as "keys
3665 * must be refreshed every N packets with cipher X".
3666 *
3667 * The renegotiation period can be disabled by setting
3668 * conf->disable_renegotiation to
3669 * MBEDTLS_SSL_RENEGOTIATION_DISABLED.
3670 *
3671 * \note When the configured transport is
3672 * MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation
3673 * period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM,
3674 * the maximum renegotiation period is 2^64 - 1.
3675 *
3676 * \param conf SSL configuration
3677 * \param period The threshold value: a big-endian 64-bit number.
3678 */
3679void mbedtls_ssl_conf_renegotiation_period(mbedtls_ssl_config *conf,
3680 const unsigned char period[8]);
3681#endif /* MBEDTLS_SSL_RENEGOTIATION */
3682
3683/**
3684 * \brief Check if there is data already read from the
3685 * underlying transport but not yet processed.
3686 *
3687 * \param ssl SSL context
3688 *
3689 * \return 0 if nothing's pending, 1 otherwise.
3690 *
3691 * \note This is different in purpose and behaviour from
3692 * \c mbedtls_ssl_get_bytes_avail in that it considers
3693 * any kind of unprocessed data, not only unread
3694 * application data. If \c mbedtls_ssl_get_bytes
3695 * returns a non-zero value, this function will
3696 * also signal pending data, but the converse does
3697 * not hold. For example, in DTLS there might be
3698 * further records waiting to be processed from
3699 * the current underlying transport's datagram.
3700 *
3701 * \note If this function returns 1 (data pending), this
3702 * does not imply that a subsequent call to
3703 * \c mbedtls_ssl_read will provide any data;
3704 * e.g., the unprocessed data might turn out
3705 * to be an alert or a handshake message.
3706 *
3707 * \note This function is useful in the following situation:
3708 * If the SSL/TLS module successfully returns from an
3709 * operation - e.g. a handshake or an application record
3710 * read - and you're awaiting incoming data next, you
3711 * must not immediately idle on the underlying transport
3712 * to have data ready, but you need to check the value
3713 * of this function first. The reason is that the desired
3714 * data might already be read but not yet processed.
3715 * If, in contrast, a previous call to the SSL/TLS module
3716 * returned MBEDTLS_ERR_SSL_WANT_READ, it is not necessary
3717 * to call this function, as the latter error code entails
3718 * that all internal data has been processed.
3719 *
3720 */
3721int mbedtls_ssl_check_pending(const mbedtls_ssl_context *ssl);
3722
3723/**
3724 * \brief Return the number of application data bytes
3725 * remaining to be read from the current record.
3726 *
3727 * \param ssl SSL context
3728 *
3729 * \return How many bytes are available in the application
3730 * data record read buffer.
3731 *
3732 * \note When working over a datagram transport, this is
3733 * useful to detect the current datagram's boundary
3734 * in case \c mbedtls_ssl_read has written the maximal
3735 * amount of data fitting into the input buffer.
3736 *
3737 */
3738size_t mbedtls_ssl_get_bytes_avail(const mbedtls_ssl_context *ssl);
3739
3740/**
3741 * \brief Return the result of the certificate verification
3742 *
3743 * \param ssl The SSL context to use.
3744 *
3745 * \return \c 0 if the certificate verification was successful.
3746 * \return \c -1u if the result is not available. This may happen
3747 * e.g. if the handshake aborts early, or a verification
3748 * callback returned a fatal error.
3749 * \return A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX
3750 * and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h.
3751 */
3752uint32_t mbedtls_ssl_get_verify_result(const mbedtls_ssl_context *ssl);
3753
3754/**
3755 * \brief Return the name of the current ciphersuite
3756 *
3757 * \param ssl SSL context
3758 *
3759 * \return a string containing the ciphersuite name
3760 */
3761const char *mbedtls_ssl_get_ciphersuite(const mbedtls_ssl_context *ssl);
3762
3763/**
3764 * \brief Return the current SSL version (SSLv3/TLSv1/etc)
3765 *
3766 * \param ssl SSL context
3767 *
3768 * \return a string containing the SSL version
3769 */
3770const char *mbedtls_ssl_get_version(const mbedtls_ssl_context *ssl);
3771
3772/**
3773 * \brief Return the (maximum) number of bytes added by the record
3774 * layer: header + encryption/MAC overhead (inc. padding)
3775 *
3776 * \note This function is not available (always returns an error)
3777 * when record compression is enabled.
3778 *
3779 * \param ssl SSL context
3780 *
3781 * \return Current maximum record expansion in bytes, or
3782 * MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if compression is
3783 * enabled, which makes expansion much less predictable
3784 */
3785int mbedtls_ssl_get_record_expansion(const mbedtls_ssl_context *ssl);
3786
3787#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
3788/**
3789 * \brief Return the maximum fragment length (payload, in bytes) for
3790 * the output buffer. For the client, this is the configured
3791 * value. For the server, it is the minimum of two - the
3792 * configured value and the negotiated one.
3793 *
3794 * \sa mbedtls_ssl_conf_max_frag_len()
3795 * \sa mbedtls_ssl_get_max_record_payload()
3796 *
3797 * \param ssl SSL context
3798 *
3799 * \return Current maximum fragment length for the output buffer.
3800 */
3801size_t mbedtls_ssl_get_output_max_frag_len(const mbedtls_ssl_context *ssl);
3802
3803/**
3804 * \brief Return the maximum fragment length (payload, in bytes) for
3805 * the input buffer. This is the negotiated maximum fragment
3806 * length, or, if there is none, MBEDTLS_SSL_MAX_CONTENT_LEN.
3807 * If it is not defined either, the value is 2^14. This function
3808 * works as its predecessor, \c mbedtls_ssl_get_max_frag_len().
3809 *
3810 * \sa mbedtls_ssl_conf_max_frag_len()
3811 * \sa mbedtls_ssl_get_max_record_payload()
3812 *
3813 * \param ssl SSL context
3814 *
3815 * \return Current maximum fragment length for the output buffer.
3816 */
3817size_t mbedtls_ssl_get_input_max_frag_len(const mbedtls_ssl_context *ssl);
3818
3819#if !defined(MBEDTLS_DEPRECATED_REMOVED)
3820
3821#if defined(MBEDTLS_DEPRECATED_WARNING)
3822#define MBEDTLS_DEPRECATED __attribute__((deprecated))
3823#else
3824#define MBEDTLS_DEPRECATED
3825#endif
3826
3827/**
3828 * \brief This function is a deprecated approach to getting the max
3829 * fragment length. Its an alias for
3830 * \c mbedtls_ssl_get_output_max_frag_len(), as the behaviour
3831 * is the same. See \c mbedtls_ssl_get_output_max_frag_len() for
3832 * more detail.
3833 *
3834 * \sa mbedtls_ssl_get_input_max_frag_len()
3835 * \sa mbedtls_ssl_get_output_max_frag_len()
3836 *
3837 * \param ssl SSL context
3838 *
3839 * \return Current maximum fragment length for the output buffer.
3840 */
3841MBEDTLS_DEPRECATED size_t mbedtls_ssl_get_max_frag_len(
3842 const mbedtls_ssl_context *ssl);
3843#endif /* MBEDTLS_DEPRECATED_REMOVED */
3844#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
3845
3846/**
3847 * \brief Return the current maximum outgoing record payload in bytes.
3848 * This takes into account the config.h setting \c
3849 * MBEDTLS_SSL_OUT_CONTENT_LEN, the configured and negotiated
3850 * max fragment length extension if used, and for DTLS the
3851 * path MTU as configured and current record expansion.
3852 *
3853 * \note With DTLS, \c mbedtls_ssl_write() will return an error if
3854 * called with a larger length value.
3855 * With TLS, \c mbedtls_ssl_write() will fragment the input if
3856 * necessary and return the number of bytes written; it is up
3857 * to the caller to call \c mbedtls_ssl_write() again in
3858 * order to send the remaining bytes if any.
3859 *
3860 * \note This function is not available (always returns an error)
3861 * when record compression is enabled.
3862 *
3863 * \sa mbedtls_ssl_set_mtu()
3864 * \sa mbedtls_ssl_get_output_max_frag_len()
3865 * \sa mbedtls_ssl_get_input_max_frag_len()
3866 * \sa mbedtls_ssl_get_record_expansion()
3867 *
3868 * \param ssl SSL context
3869 *
3870 * \return Current maximum payload for an outgoing record,
3871 * or a negative error code.
3872 */
3873int mbedtls_ssl_get_max_out_record_payload(const mbedtls_ssl_context *ssl);
3874
3875#if defined(MBEDTLS_X509_CRT_PARSE_C)
3876/**
3877 * \brief Return the peer certificate from the current connection.
3878 *
3879 * \param ssl The SSL context to use. This must be initialized and setup.
3880 *
3881 * \return The current peer certificate, if available.
3882 * The returned certificate is owned by the SSL context and
3883 * is valid only until the next call to the SSL API.
3884 * \return \c NULL if no peer certificate is available. This might
3885 * be because the chosen ciphersuite doesn't use CRTs
3886 * (PSK-based ciphersuites, for example), or because
3887 * #MBEDTLS_SSL_KEEP_PEER_CERTIFICATE has been disabled,
3888 * allowing the stack to free the peer's CRT to save memory.
3889 *
3890 * \note For one-time inspection of the peer's certificate during
3891 * the handshake, consider registering an X.509 CRT verification
3892 * callback through mbedtls_ssl_conf_verify() instead of calling
3893 * this function. Using mbedtls_ssl_conf_verify() also comes at
3894 * the benefit of allowing you to influence the verification
3895 * process, for example by masking expected and tolerated
3896 * verification failures.
3897 *
3898 * \warning You must not use the pointer returned by this function
3899 * after any further call to the SSL API, including
3900 * mbedtls_ssl_read() and mbedtls_ssl_write(); this is
3901 * because the pointer might change during renegotiation,
3902 * which happens transparently to the user.
3903 * If you want to use the certificate across API calls,
3904 * you must make a copy.
3905 */
3906const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert(const mbedtls_ssl_context *ssl);
3907#endif /* MBEDTLS_X509_CRT_PARSE_C */
3908
3909#if defined(MBEDTLS_SSL_CLI_C)
3910/**
3911 * \brief Save session in order to resume it later (client-side only)
3912 * Session data is copied to presented session structure.
3913 *
3914 *
3915 * \param ssl SSL context
3916 * \param session session context
3917 *
3918 * \return 0 if successful,
3919 * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed,
3920 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or
3921 * arguments are otherwise invalid.
3922 *
3923 * \note Only the server certificate is copied, and not the full chain,
3924 * so you should not attempt to validate the certificate again
3925 * by calling \c mbedtls_x509_crt_verify() on it.
3926 * Instead, you should use the results from the verification
3927 * in the original handshake by calling \c mbedtls_ssl_get_verify_result()
3928 * after loading the session again into a new SSL context
3929 * using \c mbedtls_ssl_set_session().
3930 *
3931 * \note Once the session object is not needed anymore, you should
3932 * free it by calling \c mbedtls_ssl_session_free().
3933 *
3934 * \sa mbedtls_ssl_set_session()
3935 */
3936int mbedtls_ssl_get_session(const mbedtls_ssl_context *ssl, mbedtls_ssl_session *session);
3937#endif /* MBEDTLS_SSL_CLI_C */
3938
3939/**
3940 * \brief Perform the SSL handshake
3941 *
3942 * \param ssl SSL context
3943 *
3944 * \return \c 0 if successful.
3945 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
3946 * if the handshake is incomplete and waiting for data to
3947 * be available for reading from or writing to the underlying
3948 * transport - in this case you must call this function again
3949 * when the underlying transport is ready for the operation.
3950 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
3951 * operation is in progress (see
3952 * mbedtls_ssl_conf_async_private_cb()) - in this case you
3953 * must call this function again when the operation is ready.
3954 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
3955 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
3956 * in this case you must call this function again to complete
3957 * the handshake when you're done attending other tasks.
3958 * \return #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED if DTLS is in use
3959 * and the client did not demonstrate reachability yet - in
3960 * this case you must stop using the context (see below).
3961 * \return Another SSL error code - in this case you must stop using
3962 * the context (see below).
3963 *
3964 * \warning If this function returns something other than
3965 * \c 0,
3966 * #MBEDTLS_ERR_SSL_WANT_READ,
3967 * #MBEDTLS_ERR_SSL_WANT_WRITE,
3968 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
3969 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
3970 * you must stop using the SSL context for reading or writing,
3971 * and either free it or call \c mbedtls_ssl_session_reset()
3972 * on it before re-using it for a new connection; the current
3973 * connection must be closed.
3974 *
3975 * \note If DTLS is in use, then you may choose to handle
3976 * #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging
3977 * purposes, as it is an expected return value rather than an
3978 * actual error, but you still need to reset/free the context.
3979 *
3980 * \note Remarks regarding event-driven DTLS:
3981 * If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
3982 * from the underlying transport layer is currently being processed,
3983 * and it is safe to idle until the timer or the underlying transport
3984 * signal a new event. This is not true for a successful handshake,
3985 * in which case the datagram of the underlying transport that is
3986 * currently being processed might or might not contain further
3987 * DTLS records.
3988 *
3989 * \note If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto
3990 * subsystem must have been initialized by calling
3991 * psa_crypto_init() before calling this function.
3992 */
3993int mbedtls_ssl_handshake(mbedtls_ssl_context *ssl);
3994
3995/**
3996 * \brief Perform a single step of the SSL handshake
3997 *
3998 * \note The state of the context (ssl->state) will be at
3999 * the next state after this function returns \c 0. Do not
4000 * call this function if state is MBEDTLS_SSL_HANDSHAKE_OVER.
4001 *
4002 * \param ssl SSL context
4003 *
4004 * \return See mbedtls_ssl_handshake().
4005 *
4006 * \warning If this function returns something other than \c 0,
4007 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
4008 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4009 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
4010 * the SSL context for reading or writing, and either free it
4011 * or call \c mbedtls_ssl_session_reset() on it before
4012 * re-using it for a new connection; the current connection
4013 * must be closed.
4014 */
4015int mbedtls_ssl_handshake_step(mbedtls_ssl_context *ssl);
4016
4017#if defined(MBEDTLS_SSL_RENEGOTIATION)
4018/**
4019 * \brief Initiate an SSL renegotiation on the running connection.
4020 * Client: perform the renegotiation right now.
4021 * Server: request renegotiation, which will be performed
4022 * during the next call to mbedtls_ssl_read() if honored by
4023 * client.
4024 *
4025 * \param ssl SSL context
4026 *
4027 * \return 0 if successful, or any mbedtls_ssl_handshake() return
4028 * value except #MBEDTLS_ERR_SSL_CLIENT_RECONNECT that can't
4029 * happen during a renegotiation.
4030 *
4031 * \warning If this function returns something other than \c 0,
4032 * #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
4033 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4034 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
4035 * the SSL context for reading or writing, and either free it
4036 * or call \c mbedtls_ssl_session_reset() on it before
4037 * re-using it for a new connection; the current connection
4038 * must be closed.
4039 *
4040 */
4041int mbedtls_ssl_renegotiate(mbedtls_ssl_context *ssl);
4042#endif /* MBEDTLS_SSL_RENEGOTIATION */
4043
4044/**
4045 * \brief Read at most 'len' application data bytes
4046 *
4047 * \param ssl SSL context
4048 * \param buf buffer that will hold the data
4049 * \param len maximum number of bytes to read
4050 *
4051 * \return The (positive) number of bytes read if successful.
4052 * \return \c 0 if the read end of the underlying transport was closed
4053 * without sending a CloseNotify beforehand, which might happen
4054 * because of various reasons (internal error of an underlying
4055 * stack, non-conformant peer not sending a CloseNotify and
4056 * such) - in this case you must stop using the context
4057 * (see below).
4058 * \return #MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY if the underlying
4059 * transport is still functional, but the peer has
4060 * acknowledged to not send anything anymore.
4061 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4062 * if the handshake is incomplete and waiting for data to
4063 * be available for reading from or writing to the underlying
4064 * transport - in this case you must call this function again
4065 * when the underlying transport is ready for the operation.
4066 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4067 * operation is in progress (see
4068 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4069 * must call this function again when the operation is ready.
4070 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4071 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4072 * in this case you must call this function again to complete
4073 * the handshake when you're done attending other tasks.
4074 * \return #MBEDTLS_ERR_SSL_CLIENT_RECONNECT if we're at the server
4075 * side of a DTLS connection and the client is initiating a
4076 * new connection using the same source port. See below.
4077 * \return Another SSL error code - in this case you must stop using
4078 * the context (see below).
4079 *
4080 * \warning If this function returns something other than
4081 * a positive value,
4082 * #MBEDTLS_ERR_SSL_WANT_READ,
4083 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4084 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
4085 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
4086 * #MBEDTLS_ERR_SSL_CLIENT_RECONNECT,
4087 * you must stop using the SSL context for reading or writing,
4088 * and either free it or call \c mbedtls_ssl_session_reset()
4089 * on it before re-using it for a new connection; the current
4090 * connection must be closed.
4091 *
4092 * \note When this function returns #MBEDTLS_ERR_SSL_CLIENT_RECONNECT
4093 * (which can only happen server-side), it means that a client
4094 * is initiating a new connection using the same source port.
4095 * You can either treat that as a connection close and wait
4096 * for the client to resend a ClientHello, or directly
4097 * continue with \c mbedtls_ssl_handshake() with the same
4098 * context (as it has been reset internally). Either way, you
4099 * must make sure this is seen by the application as a new
4100 * connection: application state, if any, should be reset, and
4101 * most importantly the identity of the client must be checked
4102 * again. WARNING: not validating the identity of the client
4103 * again, or not transmitting the new identity to the
4104 * application layer, would allow authentication bypass!
4105 *
4106 * \note Remarks regarding event-driven DTLS:
4107 * - If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
4108 * from the underlying transport layer is currently being processed,
4109 * and it is safe to idle until the timer or the underlying transport
4110 * signal a new event.
4111 * - This function may return MBEDTLS_ERR_SSL_WANT_READ even if data was
4112 * initially available on the underlying transport, as this data may have
4113 * been only e.g. duplicated messages or a renegotiation request.
4114 * Therefore, you must be prepared to receive MBEDTLS_ERR_SSL_WANT_READ even
4115 * when reacting to an incoming-data event from the underlying transport.
4116 * - On success, the datagram of the underlying transport that is currently
4117 * being processed may contain further DTLS records. You should call
4118 * \c mbedtls_ssl_check_pending to check for remaining records.
4119 *
4120 */
4121int mbedtls_ssl_read(mbedtls_ssl_context *ssl, unsigned char *buf, size_t len);
4122
4123/**
4124 * \brief Try to write exactly 'len' application data bytes
4125 *
4126 * \warning This function will do partial writes in some cases. If the
4127 * return value is non-negative but less than length, the
4128 * function must be called again with updated arguments:
4129 * buf + ret, len - ret (if ret is the return value) until
4130 * it returns a value equal to the last 'len' argument.
4131 *
4132 * \param ssl SSL context
4133 * \param buf buffer holding the data
4134 * \param len how many bytes must be written
4135 *
4136 * \return The (non-negative) number of bytes actually written if
4137 * successful (may be less than \p len).
4138 * \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
4139 * if the handshake is incomplete and waiting for data to
4140 * be available for reading from or writing to the underlying
4141 * transport - in this case you must call this function again
4142 * when the underlying transport is ready for the operation.
4143 * \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
4144 * operation is in progress (see
4145 * mbedtls_ssl_conf_async_private_cb()) - in this case you
4146 * must call this function again when the operation is ready.
4147 * \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
4148 * operation is in progress (see mbedtls_ecp_set_max_ops()) -
4149 * in this case you must call this function again to complete
4150 * the handshake when you're done attending other tasks.
4151 * \return Another SSL error code - in this case you must stop using
4152 * the context (see below).
4153 *
4154 * \warning If this function returns something other than
4155 * a non-negative value,
4156 * #MBEDTLS_ERR_SSL_WANT_READ,
4157 * #MBEDTLS_ERR_SSL_WANT_WRITE,
4158 * #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
4159 * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
4160 * you must stop using the SSL context for reading or writing,
4161 * and either free it or call \c mbedtls_ssl_session_reset()
4162 * on it before re-using it for a new connection; the current
4163 * connection must be closed.
4164 *
4165 * \note When this function returns #MBEDTLS_ERR_SSL_WANT_WRITE/READ,
4166 * it must be called later with the *same* arguments,
4167 * until it returns a value greater that or equal to 0. When
4168 * the function returns #MBEDTLS_ERR_SSL_WANT_WRITE there may be
4169 * some partial data in the output buffer, however this is not
4170 * yet sent.
4171 *
4172 * \note If the requested length is greater than the maximum
4173 * fragment length (either the built-in limit or the one set
4174 * or negotiated with the peer), then:
4175 * - with TLS, less bytes than requested are written.
4176 * - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned.
4177 * \c mbedtls_ssl_get_output_max_frag_len() may be used to
4178 * query the active maximum fragment length.
4179 *
4180 * \note Attempting to write 0 bytes will result in an empty TLS
4181 * application record being sent.
4182 */
4183int mbedtls_ssl_write(mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len);
4184
4185/**
4186 * \brief Send an alert message
4187 *
4188 * \param ssl SSL context
4189 * \param level The alert level of the message
4190 * (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL)
4191 * \param message The alert message (SSL_ALERT_MSG_*)
4192 *
4193 * \return 0 if successful, or a specific SSL error code.
4194 *
4195 * \note If this function returns something other than 0 or
4196 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
4197 * the SSL context for reading or writing, and either free it or
4198 * call \c mbedtls_ssl_session_reset() on it before re-using it
4199 * for a new connection; the current connection must be closed.
4200 */
4201int mbedtls_ssl_send_alert_message(mbedtls_ssl_context *ssl,
4202 unsigned char level,
4203 unsigned char message);
4204/**
4205 * \brief Notify the peer that the connection is being closed
4206 *
4207 * \param ssl SSL context
4208 *
4209 * \return 0 if successful, or a specific SSL error code.
4210 *
4211 * \note If this function returns something other than 0 or
4212 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
4213 * the SSL context for reading or writing, and either free it or
4214 * call \c mbedtls_ssl_session_reset() on it before re-using it
4215 * for a new connection; the current connection must be closed.
4216 */
4217int mbedtls_ssl_close_notify(mbedtls_ssl_context *ssl);
4218
4219/**
4220 * \brief Free referenced items in an SSL context and clear memory
4221 *
4222 * \param ssl SSL context
4223 */
4224void mbedtls_ssl_free(mbedtls_ssl_context *ssl);
4225
4226#if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION)
4227/**
4228 * \brief Save an active connection as serialized data in a buffer.
4229 * This allows the freeing or re-using of the SSL context
4230 * while still picking up the connection later in a way that
4231 * it entirely transparent to the peer.
4232 *
4233 * \see mbedtls_ssl_context_load()
4234 *
4235 * \note This feature is currently only available under certain
4236 * conditions, see the documentation of the return value
4237 * #MBEDTLS_ERR_SSL_BAD_INPUT_DATA for details.
4238 *
4239 * \note When this function succeeds, it calls
4240 * mbedtls_ssl_session_reset() on \p ssl which as a result is
4241 * no longer associated with the connection that has been
4242 * serialized. This avoids creating copies of the connection
4243 * state. You're then free to either re-use the context
4244 * structure for a different connection, or call
4245 * mbedtls_ssl_free() on it. See the documentation of
4246 * mbedtls_ssl_session_reset() for more details.
4247 *
4248 * \param ssl The SSL context to save. On success, it is no longer
4249 * associated with the connection that has been serialized.
4250 * \param buf The buffer to write the serialized data to. It must be a
4251 * writeable buffer of at least \p buf_len bytes, or may be \c
4252 * NULL if \p buf_len is \c 0.
4253 * \param buf_len The number of bytes available for writing in \p buf.
4254 * \param olen The size in bytes of the data that has been or would have
4255 * been written. It must point to a valid \c size_t.
4256 *
4257 * \note \p olen is updated to the correct value regardless of
4258 * whether \p buf_len was large enough. This makes it possible
4259 * to determine the necessary size by calling this function
4260 * with \p buf set to \c NULL and \p buf_len to \c 0. However,
4261 * the value of \p olen is only guaranteed to be correct when
4262 * the function returns #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL or
4263 * \c 0. If the return value is different, then the value of
4264 * \p olen is undefined.
4265 *
4266 * \return \c 0 if successful.
4267 * \return #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small.
4268 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed
4269 * while resetting the context.
4270 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if a handshake is in
4271 * progress, or there is pending data for reading or sending,
4272 * or the connection does not use DTLS 1.2 with an AEAD
4273 * ciphersuite, or renegotiation is enabled.
4274 */
4275int mbedtls_ssl_context_save(mbedtls_ssl_context *ssl,
4276 unsigned char *buf,
4277 size_t buf_len,
4278 size_t *olen);
4279
4280/**
4281 * \brief Load serialized connection data to an SSL context.
4282 *
4283 * \see mbedtls_ssl_context_save()
4284 *
4285 * \warning The same serialized data must never be loaded into more
4286 * that one context. In order to ensure that, after
4287 * successfully loading serialized data to an SSL context, you
4288 * should immediately destroy or invalidate all copies of the
4289 * serialized data that was loaded. Loading the same data in
4290 * more than one context would cause severe security failures
4291 * including but not limited to loss of confidentiality.
4292 *
4293 * \note Before calling this function, the SSL context must be
4294 * prepared in one of the two following ways. The first way is
4295 * to take a context freshly initialised with
4296 * mbedtls_ssl_init() and call mbedtls_ssl_setup() on it with
4297 * the same ::mbedtls_ssl_config structure that was used in
4298 * the original connection. The second way is to
4299 * call mbedtls_ssl_session_reset() on a context that was
4300 * previously prepared as above but used in the meantime.
4301 * Either way, you must not use the context to perform a
4302 * handshake between calling mbedtls_ssl_setup() or
4303 * mbedtls_ssl_session_reset() and calling this function. You
4304 * may however call other setter functions in that time frame
4305 * as indicated in the note below.
4306 *
4307 * \note Before or after calling this function successfully, you
4308 * also need to configure some connection-specific callbacks
4309 * and settings before you can use the connection again
4310 * (unless they were already set before calling
4311 * mbedtls_ssl_session_reset() and the values are suitable for
4312 * the present connection). Specifically, you want to call
4313 * at least mbedtls_ssl_set_bio() and
4314 * mbedtls_ssl_set_timer_cb(). All other SSL setter functions
4315 * are not necessary to call, either because they're only used
4316 * in handshakes, or because the setting is already saved. You
4317 * might choose to call them anyway, for example in order to
4318 * share code between the cases of establishing a new
4319 * connection and the case of loading an already-established
4320 * connection.
4321 *
4322 * \note If you have new information about the path MTU, you want to
4323 * call mbedtls_ssl_set_mtu() after calling this function, as
4324 * otherwise this function would overwrite your
4325 * newly-configured value with the value that was active when
4326 * the context was saved.
4327 *
4328 * \note When this function returns an error code, it calls
4329 * mbedtls_ssl_free() on \p ssl. In this case, you need to
4330 * prepare the context with the usual sequence starting with a
4331 * call to mbedtls_ssl_init() if you want to use it again.
4332 *
4333 * \param ssl The SSL context structure to be populated. It must have
4334 * been prepared as described in the note above.
4335 * \param buf The buffer holding the serialized connection data. It must
4336 * be a readable buffer of at least \p len bytes.
4337 * \param len The size of the serialized data in bytes.
4338 *
4339 * \return \c 0 if successful.
4340 * \return #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed.
4341 * \return #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data
4342 * comes from a different Mbed TLS version or build.
4343 * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
4344 */
4345int mbedtls_ssl_context_load(mbedtls_ssl_context *ssl,
4346 const unsigned char *buf,
4347 size_t len);
4348#endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */
4349
4350/**
4351 * \brief Initialize an SSL configuration context
4352 * Just makes the context ready for
4353 * mbedtls_ssl_config_defaults() or mbedtls_ssl_config_free().
4354 *
4355 * \note You need to call mbedtls_ssl_config_defaults() unless you
4356 * manually set all of the relevant fields yourself.
4357 *
4358 * \param conf SSL configuration context
4359 */
4360void mbedtls_ssl_config_init(mbedtls_ssl_config *conf);
4361
4362/**
4363 * \brief Load reasonable default SSL configuration values.
4364 * (You need to call mbedtls_ssl_config_init() first.)
4365 *
4366 * \param conf SSL configuration context
4367 * \param endpoint MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER
4368 * \param transport MBEDTLS_SSL_TRANSPORT_STREAM for TLS, or
4369 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS
4370 * \param preset a MBEDTLS_SSL_PRESET_XXX value
4371 *
4372 * \note See \c mbedtls_ssl_conf_transport() for notes on DTLS.
4373 *
4374 * \return 0 if successful, or
4375 * MBEDTLS_ERR_XXX_ALLOC_FAILED on memory allocation error.
4376 */
4377int mbedtls_ssl_config_defaults(mbedtls_ssl_config *conf,
4378 int endpoint, int transport, int preset);
4379
4380/**
4381 * \brief Free an SSL configuration context
4382 *
4383 * \param conf SSL configuration context
4384 */
4385void mbedtls_ssl_config_free(mbedtls_ssl_config *conf);
4386
4387/**
4388 * \brief Initialize SSL session structure
4389 *
4390 * \param session SSL session
4391 */
4392void mbedtls_ssl_session_init(mbedtls_ssl_session *session);
4393
4394/**
4395 * \brief Free referenced items in an SSL session including the
4396 * peer certificate and clear memory
4397 *
4398 * \note A session object can be freed even if the SSL context
4399 * that was used to retrieve the session is still in use.
4400 *
4401 * \param session SSL session
4402 */
4403void mbedtls_ssl_session_free(mbedtls_ssl_session *session);
4404
4405/**
4406 * \brief TLS-PRF function for key derivation.
4407 *
4408 * \param prf The tls_prf type function type to be used.
4409 * \param secret Secret for the key derivation function.
4410 * \param slen Length of the secret.
4411 * \param label String label for the key derivation function,
4412 * terminated with null character.
4413 * \param random Random bytes.
4414 * \param rlen Length of the random bytes buffer.
4415 * \param dstbuf The buffer holding the derived key.
4416 * \param dlen Length of the output buffer.
4417 *
4418 * \return 0 on success. An SSL specific error on failure.
4419 */
4420int mbedtls_ssl_tls_prf(const mbedtls_tls_prf_types prf,
4421 const unsigned char *secret, size_t slen,
4422 const char *label,
4423 const unsigned char *random, size_t rlen,
4424 unsigned char *dstbuf, size_t dlen);
4425
4426#ifdef __cplusplus
4427}
4428#endif
4429
4430#endif /* ssl.h */
4431