xref: /optee_os/lib/libmbedtls/mbedtls/library/ssl_misc.h (revision 5d5d7d0b1c038a6836be9f0b38585f5aa6a4dd01)
1 /**
2  * \file ssl_misc.h
3  *
4  * \brief Internal functions shared by the SSL modules
5  */
6 /*
7  *  Copyright The Mbed TLS Contributors
8  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
9  */
10 #ifndef MBEDTLS_SSL_MISC_H
11 #define MBEDTLS_SSL_MISC_H
12 
13 #include "mbedtls/build_info.h"
14 #include "common.h"
15 
16 #include "mbedtls/error.h"
17 
18 #include "mbedtls/ssl.h"
19 #include "mbedtls/cipher.h"
20 
21 #if defined(MBEDTLS_USE_PSA_CRYPTO) || defined(MBEDTLS_SSL_PROTO_TLS1_3)
22 #include "psa/crypto.h"
23 #include "psa_util_internal.h"
24 #endif
25 
26 #if defined(MBEDTLS_MD_CAN_MD5)
27 #include "mbedtls/md5.h"
28 #endif
29 
30 #if defined(MBEDTLS_MD_CAN_SHA1)
31 #include "mbedtls/sha1.h"
32 #endif
33 
34 #if defined(MBEDTLS_MD_CAN_SHA256)
35 #include "mbedtls/sha256.h"
36 #endif
37 
38 #if defined(MBEDTLS_MD_CAN_SHA512)
39 #include "mbedtls/sha512.h"
40 #endif
41 
42 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) && \
43     !defined(MBEDTLS_USE_PSA_CRYPTO)
44 #include "mbedtls/ecjpake.h"
45 #endif
46 
47 #include "mbedtls/pk.h"
48 #include "ssl_ciphersuites_internal.h"
49 #include "x509_internal.h"
50 #include "pk_internal.h"
51 
52 
53 /* Shorthand for restartable ECC */
54 #if defined(MBEDTLS_ECP_RESTARTABLE) && \
55     defined(MBEDTLS_SSL_CLI_C) && \
56     defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
57     defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
58 #define MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED
59 #endif
60 
61 #define MBEDTLS_SSL_INITIAL_HANDSHAKE           0
62 #define MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS   1   /* In progress */
63 #define MBEDTLS_SSL_RENEGOTIATION_DONE          2   /* Done or aborted */
64 #define MBEDTLS_SSL_RENEGOTIATION_PENDING       3   /* Requested (server only) */
65 
66 /* Faked handshake message identity for HelloRetryRequest. */
67 #define MBEDTLS_SSL_TLS1_3_HS_HELLO_RETRY_REQUEST (-MBEDTLS_SSL_HS_SERVER_HELLO)
68 
69 /*
70  * Internal identity of handshake extensions
71  */
72 #define MBEDTLS_SSL_EXT_ID_UNRECOGNIZED                0
73 #define MBEDTLS_SSL_EXT_ID_SERVERNAME                  1
74 #define MBEDTLS_SSL_EXT_ID_SERVERNAME_HOSTNAME         1
75 #define MBEDTLS_SSL_EXT_ID_MAX_FRAGMENT_LENGTH         2
76 #define MBEDTLS_SSL_EXT_ID_STATUS_REQUEST              3
77 #define MBEDTLS_SSL_EXT_ID_SUPPORTED_GROUPS            4
78 #define MBEDTLS_SSL_EXT_ID_SUPPORTED_ELLIPTIC_CURVES   4
79 #define MBEDTLS_SSL_EXT_ID_SIG_ALG                     5
80 #define MBEDTLS_SSL_EXT_ID_USE_SRTP                    6
81 #define MBEDTLS_SSL_EXT_ID_HEARTBEAT                   7
82 #define MBEDTLS_SSL_EXT_ID_ALPN                        8
83 #define MBEDTLS_SSL_EXT_ID_SCT                         9
84 #define MBEDTLS_SSL_EXT_ID_CLI_CERT_TYPE              10
85 #define MBEDTLS_SSL_EXT_ID_SERV_CERT_TYPE             11
86 #define MBEDTLS_SSL_EXT_ID_PADDING                    12
87 #define MBEDTLS_SSL_EXT_ID_PRE_SHARED_KEY             13
88 #define MBEDTLS_SSL_EXT_ID_EARLY_DATA                 14
89 #define MBEDTLS_SSL_EXT_ID_SUPPORTED_VERSIONS         15
90 #define MBEDTLS_SSL_EXT_ID_COOKIE                     16
91 #define MBEDTLS_SSL_EXT_ID_PSK_KEY_EXCHANGE_MODES     17
92 #define MBEDTLS_SSL_EXT_ID_CERT_AUTH                  18
93 #define MBEDTLS_SSL_EXT_ID_OID_FILTERS                19
94 #define MBEDTLS_SSL_EXT_ID_POST_HANDSHAKE_AUTH        20
95 #define MBEDTLS_SSL_EXT_ID_SIG_ALG_CERT               21
96 #define MBEDTLS_SSL_EXT_ID_KEY_SHARE                  22
97 #define MBEDTLS_SSL_EXT_ID_TRUNCATED_HMAC             23
98 #define MBEDTLS_SSL_EXT_ID_SUPPORTED_POINT_FORMATS    24
99 #define MBEDTLS_SSL_EXT_ID_ENCRYPT_THEN_MAC           25
100 #define MBEDTLS_SSL_EXT_ID_EXTENDED_MASTER_SECRET     26
101 #define MBEDTLS_SSL_EXT_ID_SESSION_TICKET             27
102 #define MBEDTLS_SSL_EXT_ID_RECORD_SIZE_LIMIT          28
103 
104 /* Utility for translating IANA extension type. */
105 uint32_t mbedtls_ssl_get_extension_id(unsigned int extension_type);
106 uint32_t mbedtls_ssl_get_extension_mask(unsigned int extension_type);
107 /* Macros used to define mask constants */
108 #define MBEDTLS_SSL_EXT_MASK(id)       (1ULL << (MBEDTLS_SSL_EXT_ID_##id))
109 /* Reset value of extension mask */
110 #define MBEDTLS_SSL_EXT_MASK_NONE                                              0
111 
112 /* In messages containing extension requests, we should ignore unrecognized
113  * extensions. In messages containing extension responses, unrecognized
114  * extensions should result in handshake abortion. Messages containing
115  * extension requests include ClientHello, CertificateRequest and
116  * NewSessionTicket. Messages containing extension responses include
117  * ServerHello, HelloRetryRequest, EncryptedExtensions and Certificate.
118  *
119  * RFC 8446 section 4.1.3
120  *
121  * The ServerHello MUST only include extensions which are required to establish
122  * the cryptographic context and negotiate the protocol version.
123  *
124  * RFC 8446 section 4.2
125  *
126  * If an implementation receives an extension which it recognizes and which is
127  * not specified for the message in which it appears, it MUST abort the handshake
128  * with an "illegal_parameter" alert.
129  */
130 
131 /* Extensions that are not recognized by TLS 1.3 */
132 #define MBEDTLS_SSL_TLS1_3_EXT_MASK_UNRECOGNIZED                               \
133     (MBEDTLS_SSL_EXT_MASK(SUPPORTED_POINT_FORMATS)                | \
134      MBEDTLS_SSL_EXT_MASK(ENCRYPT_THEN_MAC)                       | \
135      MBEDTLS_SSL_EXT_MASK(EXTENDED_MASTER_SECRET)                 | \
136      MBEDTLS_SSL_EXT_MASK(SESSION_TICKET)                         | \
137      MBEDTLS_SSL_EXT_MASK(TRUNCATED_HMAC)                         | \
138      MBEDTLS_SSL_EXT_MASK(UNRECOGNIZED))
139 
140 /* RFC 8446 section 4.2. Allowed extensions for ClientHello */
141 #define MBEDTLS_SSL_TLS1_3_ALLOWED_EXTS_OF_CH                                  \
142     (MBEDTLS_SSL_EXT_MASK(SERVERNAME)                             | \
143      MBEDTLS_SSL_EXT_MASK(MAX_FRAGMENT_LENGTH)                    | \
144      MBEDTLS_SSL_EXT_MASK(STATUS_REQUEST)                         | \
145      MBEDTLS_SSL_EXT_MASK(SUPPORTED_GROUPS)                       | \
146      MBEDTLS_SSL_EXT_MASK(SIG_ALG)                                | \
147      MBEDTLS_SSL_EXT_MASK(USE_SRTP)                               | \
148      MBEDTLS_SSL_EXT_MASK(HEARTBEAT)                              | \
149      MBEDTLS_SSL_EXT_MASK(ALPN)                                   | \
150      MBEDTLS_SSL_EXT_MASK(SCT)                                    | \
151      MBEDTLS_SSL_EXT_MASK(CLI_CERT_TYPE)                          | \
152      MBEDTLS_SSL_EXT_MASK(SERV_CERT_TYPE)                         | \
153      MBEDTLS_SSL_EXT_MASK(PADDING)                                | \
154      MBEDTLS_SSL_EXT_MASK(KEY_SHARE)                              | \
155      MBEDTLS_SSL_EXT_MASK(PRE_SHARED_KEY)                         | \
156      MBEDTLS_SSL_EXT_MASK(PSK_KEY_EXCHANGE_MODES)                 | \
157      MBEDTLS_SSL_EXT_MASK(EARLY_DATA)                             | \
158      MBEDTLS_SSL_EXT_MASK(COOKIE)                                 | \
159      MBEDTLS_SSL_EXT_MASK(SUPPORTED_VERSIONS)                     | \
160      MBEDTLS_SSL_EXT_MASK(CERT_AUTH)                              | \
161      MBEDTLS_SSL_EXT_MASK(POST_HANDSHAKE_AUTH)                    | \
162      MBEDTLS_SSL_EXT_MASK(SIG_ALG_CERT)                           | \
163      MBEDTLS_SSL_EXT_MASK(RECORD_SIZE_LIMIT)                      | \
164      MBEDTLS_SSL_TLS1_3_EXT_MASK_UNRECOGNIZED)
165 
166 /* RFC 8446 section 4.2. Allowed extensions for EncryptedExtensions */
167 #define MBEDTLS_SSL_TLS1_3_ALLOWED_EXTS_OF_EE                                  \
168     (MBEDTLS_SSL_EXT_MASK(SERVERNAME)                             | \
169      MBEDTLS_SSL_EXT_MASK(MAX_FRAGMENT_LENGTH)                    | \
170      MBEDTLS_SSL_EXT_MASK(SUPPORTED_GROUPS)                       | \
171      MBEDTLS_SSL_EXT_MASK(USE_SRTP)                               | \
172      MBEDTLS_SSL_EXT_MASK(HEARTBEAT)                              | \
173      MBEDTLS_SSL_EXT_MASK(ALPN)                                   | \
174      MBEDTLS_SSL_EXT_MASK(CLI_CERT_TYPE)                          | \
175      MBEDTLS_SSL_EXT_MASK(SERV_CERT_TYPE)                         | \
176      MBEDTLS_SSL_EXT_MASK(EARLY_DATA)                             | \
177      MBEDTLS_SSL_EXT_MASK(RECORD_SIZE_LIMIT))
178 
179 /* RFC 8446 section 4.2. Allowed extensions for CertificateRequest */
180 #define MBEDTLS_SSL_TLS1_3_ALLOWED_EXTS_OF_CR                                  \
181     (MBEDTLS_SSL_EXT_MASK(STATUS_REQUEST)                         | \
182      MBEDTLS_SSL_EXT_MASK(SIG_ALG)                                | \
183      MBEDTLS_SSL_EXT_MASK(SCT)                                    | \
184      MBEDTLS_SSL_EXT_MASK(CERT_AUTH)                              | \
185      MBEDTLS_SSL_EXT_MASK(OID_FILTERS)                            | \
186      MBEDTLS_SSL_EXT_MASK(SIG_ALG_CERT)                           | \
187      MBEDTLS_SSL_TLS1_3_EXT_MASK_UNRECOGNIZED)
188 
189 /* RFC 8446 section 4.2. Allowed extensions for Certificate */
190 #define MBEDTLS_SSL_TLS1_3_ALLOWED_EXTS_OF_CT                                  \
191     (MBEDTLS_SSL_EXT_MASK(STATUS_REQUEST)                         | \
192      MBEDTLS_SSL_EXT_MASK(SCT))
193 
194 /* RFC 8446 section 4.2. Allowed extensions for ServerHello */
195 #define MBEDTLS_SSL_TLS1_3_ALLOWED_EXTS_OF_SH                                  \
196     (MBEDTLS_SSL_EXT_MASK(KEY_SHARE)                              | \
197      MBEDTLS_SSL_EXT_MASK(PRE_SHARED_KEY)                         | \
198      MBEDTLS_SSL_EXT_MASK(SUPPORTED_VERSIONS))
199 
200 /* RFC 8446 section 4.2. Allowed extensions for HelloRetryRequest */
201 #define MBEDTLS_SSL_TLS1_3_ALLOWED_EXTS_OF_HRR                                 \
202     (MBEDTLS_SSL_EXT_MASK(KEY_SHARE)                              | \
203      MBEDTLS_SSL_EXT_MASK(COOKIE)                                 | \
204      MBEDTLS_SSL_EXT_MASK(SUPPORTED_VERSIONS))
205 
206 /* RFC 8446 section 4.2. Allowed extensions for NewSessionTicket */
207 #define MBEDTLS_SSL_TLS1_3_ALLOWED_EXTS_OF_NST                                 \
208     (MBEDTLS_SSL_EXT_MASK(EARLY_DATA)                             | \
209      MBEDTLS_SSL_TLS1_3_EXT_MASK_UNRECOGNIZED)
210 
211 /*
212  * Helper macros for function call with return check.
213  */
214 /*
215  * Exit when return non-zero value
216  */
217 #define MBEDTLS_SSL_PROC_CHK(f)                               \
218     do {                                                        \
219         ret = (f);                                            \
220         if (ret != 0)                                          \
221         {                                                       \
222             goto cleanup;                                       \
223         }                                                       \
224     } while (0)
225 /*
226  * Exit when return negative value
227  */
228 #define MBEDTLS_SSL_PROC_CHK_NEG(f)                           \
229     do {                                                        \
230         ret = (f);                                            \
231         if (ret < 0)                                           \
232         {                                                       \
233             goto cleanup;                                       \
234         }                                                       \
235     } while (0)
236 
237 /*
238  * DTLS retransmission states, see RFC 6347 4.2.4
239  *
240  * The SENDING state is merged in PREPARING for initial sends,
241  * but is distinct for resends.
242  *
243  * Note: initial state is wrong for server, but is not used anyway.
244  */
245 #define MBEDTLS_SSL_RETRANS_PREPARING       0
246 #define MBEDTLS_SSL_RETRANS_SENDING         1
247 #define MBEDTLS_SSL_RETRANS_WAITING         2
248 #define MBEDTLS_SSL_RETRANS_FINISHED        3
249 
250 /*
251  * Allow extra bytes for record, authentication and encryption overhead:
252  * counter (8) + header (5) + IV(16) + MAC (16-48) + padding (0-256).
253  */
254 
255 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
256 
257 /* This macro determines whether CBC is supported. */
258 #if defined(MBEDTLS_SSL_HAVE_CBC)      &&                                  \
259     (defined(MBEDTLS_SSL_HAVE_AES)     ||                                  \
260     defined(MBEDTLS_SSL_HAVE_CAMELLIA) ||                                  \
261     defined(MBEDTLS_SSL_HAVE_ARIA))
262 #define MBEDTLS_SSL_SOME_SUITES_USE_CBC
263 #endif
264 
265 /* This macro determines whether a ciphersuite using a
266  * stream cipher can be used. */
267 #if defined(MBEDTLS_CIPHER_NULL_CIPHER)
268 #define MBEDTLS_SSL_SOME_SUITES_USE_STREAM
269 #endif
270 
271 /* This macro determines whether the CBC construct used in TLS 1.2 is supported. */
272 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC) && \
273     defined(MBEDTLS_SSL_PROTO_TLS1_2)
274 #define MBEDTLS_SSL_SOME_SUITES_USE_TLS_CBC
275 #endif
276 
277 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_STREAM) || \
278     defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC)
279 #define MBEDTLS_SSL_SOME_SUITES_USE_MAC
280 #endif
281 
282 /* This macro determines whether a ciphersuite uses Encrypt-then-MAC with CBC */
283 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC) && \
284     defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
285 #define MBEDTLS_SSL_SOME_SUITES_USE_CBC_ETM
286 #endif
287 
288 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
289 
290 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC)
291 /* Ciphersuites using HMAC */
292 #if defined(MBEDTLS_MD_CAN_SHA384)
293 #define MBEDTLS_SSL_MAC_ADD                 48  /* SHA-384 used for HMAC */
294 #elif defined(MBEDTLS_MD_CAN_SHA256)
295 #define MBEDTLS_SSL_MAC_ADD                 32  /* SHA-256 used for HMAC */
296 #else
297 #define MBEDTLS_SSL_MAC_ADD                 20  /* SHA-1   used for HMAC */
298 #endif
299 #else /* MBEDTLS_SSL_SOME_SUITES_USE_MAC */
300 /* AEAD ciphersuites: GCM and CCM use a 128 bits tag */
301 #define MBEDTLS_SSL_MAC_ADD                 16
302 #endif
303 
304 #if defined(MBEDTLS_SSL_HAVE_CBC)
305 #define MBEDTLS_SSL_PADDING_ADD            256
306 #else
307 #define MBEDTLS_SSL_PADDING_ADD              0
308 #endif
309 
310 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
311 #define MBEDTLS_SSL_MAX_CID_EXPANSION      MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY
312 #else
313 #define MBEDTLS_SSL_MAX_CID_EXPANSION        0
314 #endif
315 
316 #define MBEDTLS_SSL_PAYLOAD_OVERHEAD (MBEDTLS_MAX_IV_LENGTH +          \
317                                       MBEDTLS_SSL_MAC_ADD +            \
318                                       MBEDTLS_SSL_PADDING_ADD +        \
319                                       MBEDTLS_SSL_MAX_CID_EXPANSION    \
320                                       )
321 
322 #define MBEDTLS_SSL_IN_PAYLOAD_LEN (MBEDTLS_SSL_PAYLOAD_OVERHEAD + \
323                                     (MBEDTLS_SSL_IN_CONTENT_LEN))
324 
325 #define MBEDTLS_SSL_OUT_PAYLOAD_LEN (MBEDTLS_SSL_PAYLOAD_OVERHEAD + \
326                                      (MBEDTLS_SSL_OUT_CONTENT_LEN))
327 
328 /* The maximum number of buffered handshake messages. */
329 #define MBEDTLS_SSL_MAX_BUFFERED_HS 4
330 
331 /* Maximum length we can advertise as our max content length for
332    RFC 6066 max_fragment_length extension negotiation purposes
333    (the lesser of both sizes, if they are unequal.)
334  */
335 #define MBEDTLS_TLS_EXT_ADV_CONTENT_LEN (                            \
336         (MBEDTLS_SSL_IN_CONTENT_LEN > MBEDTLS_SSL_OUT_CONTENT_LEN)   \
337         ? (MBEDTLS_SSL_OUT_CONTENT_LEN)                            \
338         : (MBEDTLS_SSL_IN_CONTENT_LEN)                             \
339         )
340 
341 /* Maximum size in bytes of list in signature algorithms ext., RFC 5246/8446 */
342 #define MBEDTLS_SSL_MAX_SIG_ALG_LIST_LEN       65534
343 
344 /* Minimum size in bytes of list in signature algorithms ext., RFC 5246/8446 */
345 #define MBEDTLS_SSL_MIN_SIG_ALG_LIST_LEN       2
346 
347 /* Maximum size in bytes of list in supported elliptic curve ext., RFC 4492 */
348 #define MBEDTLS_SSL_MAX_CURVE_LIST_LEN         65535
349 
350 #define MBEDTLS_RECEIVED_SIG_ALGS_SIZE         20
351 
352 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
353 
354 #define MBEDTLS_TLS_SIG_NONE MBEDTLS_TLS1_3_SIG_NONE
355 
356 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
357 #define MBEDTLS_SSL_TLS12_SIG_AND_HASH_ALG(sig, hash) ((hash << 8) | sig)
358 #define MBEDTLS_SSL_TLS12_SIG_ALG_FROM_SIG_AND_HASH_ALG(alg) (alg & 0xFF)
359 #define MBEDTLS_SSL_TLS12_HASH_ALG_FROM_SIG_AND_HASH_ALG(alg) (alg >> 8)
360 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
361 
362 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
363 
364 /*
365  * Check that we obey the standard's message size bounds
366  */
367 
368 #if MBEDTLS_SSL_IN_CONTENT_LEN > 16384
369 #error "Bad configuration - incoming record content too large."
370 #endif
371 
372 #if MBEDTLS_SSL_OUT_CONTENT_LEN > 16384
373 #error "Bad configuration - outgoing record content too large."
374 #endif
375 
376 #if MBEDTLS_SSL_IN_PAYLOAD_LEN > MBEDTLS_SSL_IN_CONTENT_LEN + 2048
377 #error "Bad configuration - incoming protected record payload too large."
378 #endif
379 
380 #if MBEDTLS_SSL_OUT_PAYLOAD_LEN > MBEDTLS_SSL_OUT_CONTENT_LEN + 2048
381 #error "Bad configuration - outgoing protected record payload too large."
382 #endif
383 
384 /* Calculate buffer sizes */
385 
386 /* Note: Even though the TLS record header is only 5 bytes
387    long, we're internally using 8 bytes to store the
388    implicit sequence number. */
389 #define MBEDTLS_SSL_HEADER_LEN 13
390 
391 #if !defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
392 #define MBEDTLS_SSL_IN_BUFFER_LEN  \
393     ((MBEDTLS_SSL_HEADER_LEN) + (MBEDTLS_SSL_IN_PAYLOAD_LEN))
394 #else
395 #define MBEDTLS_SSL_IN_BUFFER_LEN  \
396     ((MBEDTLS_SSL_HEADER_LEN) + (MBEDTLS_SSL_IN_PAYLOAD_LEN) \
397      + (MBEDTLS_SSL_CID_IN_LEN_MAX))
398 #endif
399 
400 #if !defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
401 #define MBEDTLS_SSL_OUT_BUFFER_LEN  \
402     ((MBEDTLS_SSL_HEADER_LEN) + (MBEDTLS_SSL_OUT_PAYLOAD_LEN))
403 #else
404 #define MBEDTLS_SSL_OUT_BUFFER_LEN                               \
405     ((MBEDTLS_SSL_HEADER_LEN) + (MBEDTLS_SSL_OUT_PAYLOAD_LEN)    \
406      + (MBEDTLS_SSL_CID_OUT_LEN_MAX))
407 #endif
408 
409 #define MBEDTLS_CLIENT_HELLO_RANDOM_LEN 32
410 #define MBEDTLS_SERVER_HELLO_RANDOM_LEN 32
411 
412 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
413 /**
414  * \brief          Return the maximum fragment length (payload, in bytes) for
415  *                 the output buffer. For the client, this is the configured
416  *                 value. For the server, it is the minimum of two - the
417  *                 configured value and the negotiated one.
418  *
419  * \sa             mbedtls_ssl_conf_max_frag_len()
420  * \sa             mbedtls_ssl_get_max_out_record_payload()
421  *
422  * \param ssl      SSL context
423  *
424  * \return         Current maximum fragment length for the output buffer.
425  */
426 size_t mbedtls_ssl_get_output_max_frag_len(const mbedtls_ssl_context *ssl);
427 
428 /**
429  * \brief          Return the maximum fragment length (payload, in bytes) for
430  *                 the input buffer. This is the negotiated maximum fragment
431  *                 length, or, if there is none, MBEDTLS_SSL_IN_CONTENT_LEN.
432  *                 If it is not defined either, the value is 2^14. This function
433  *                 works as its predecessor, \c mbedtls_ssl_get_max_frag_len().
434  *
435  * \sa             mbedtls_ssl_conf_max_frag_len()
436  * \sa             mbedtls_ssl_get_max_in_record_payload()
437  *
438  * \param ssl      SSL context
439  *
440  * \return         Current maximum fragment length for the output buffer.
441  */
442 size_t mbedtls_ssl_get_input_max_frag_len(const mbedtls_ssl_context *ssl);
443 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
444 
445 #if defined(MBEDTLS_SSL_RECORD_SIZE_LIMIT)
446 /**
447  * \brief    Get the size limit in bytes for the protected outgoing records
448  *           as defined in RFC 8449
449  *
450  * \param ssl      SSL context
451  *
452  * \return         The size limit in bytes for the protected outgoing
453  *                 records as defined in RFC 8449.
454  */
455 size_t mbedtls_ssl_get_output_record_size_limit(const mbedtls_ssl_context *ssl);
456 #endif /* MBEDTLS_SSL_RECORD_SIZE_LIMIT */
457 
458 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
459 static inline size_t mbedtls_ssl_get_output_buflen(const mbedtls_ssl_context *ctx)
460 {
461 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
462     return mbedtls_ssl_get_output_max_frag_len(ctx)
463            + MBEDTLS_SSL_HEADER_LEN + MBEDTLS_SSL_PAYLOAD_OVERHEAD
464            + MBEDTLS_SSL_CID_OUT_LEN_MAX;
465 #else
466     return mbedtls_ssl_get_output_max_frag_len(ctx)
467            + MBEDTLS_SSL_HEADER_LEN + MBEDTLS_SSL_PAYLOAD_OVERHEAD;
468 #endif
469 }
470 
471 static inline size_t mbedtls_ssl_get_input_buflen(const mbedtls_ssl_context *ctx)
472 {
473 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
474     return mbedtls_ssl_get_input_max_frag_len(ctx)
475            + MBEDTLS_SSL_HEADER_LEN + MBEDTLS_SSL_PAYLOAD_OVERHEAD
476            + MBEDTLS_SSL_CID_IN_LEN_MAX;
477 #else
478     return mbedtls_ssl_get_input_max_frag_len(ctx)
479            + MBEDTLS_SSL_HEADER_LEN + MBEDTLS_SSL_PAYLOAD_OVERHEAD;
480 #endif
481 }
482 #endif
483 
484 /*
485  * TLS extension flags (for extensions with outgoing ServerHello content
486  * that need it (e.g. for RENEGOTIATION_INFO the server already knows because
487  * of state of the renegotiation flag, so no indicator is required)
488  */
489 #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS_PRESENT (1 << 0)
490 #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP_OK                 (1 << 1)
491 
492 /**
493  * \brief        This function checks if the remaining size in a buffer is
494  *               greater or equal than a needed space.
495  *
496  * \param cur    Pointer to the current position in the buffer.
497  * \param end    Pointer to one past the end of the buffer.
498  * \param need   Needed space in bytes.
499  *
500  * \return       Zero if the needed space is available in the buffer, non-zero
501  *               otherwise.
502  */
503 #if !defined(MBEDTLS_TEST_HOOKS)
504 static inline int mbedtls_ssl_chk_buf_ptr(const uint8_t *cur,
505                                           const uint8_t *end, size_t need)
506 {
507     return (cur > end) || (need > (size_t) (end - cur));
508 }
509 #else
510 typedef struct {
511     const uint8_t *cur;
512     const uint8_t *end;
513     size_t need;
514 } mbedtls_ssl_chk_buf_ptr_args;
515 
516 void mbedtls_ssl_set_chk_buf_ptr_fail_args(
517     const uint8_t *cur, const uint8_t *end, size_t need);
518 void mbedtls_ssl_reset_chk_buf_ptr_fail_args(void);
519 
520 MBEDTLS_CHECK_RETURN_CRITICAL
521 int mbedtls_ssl_cmp_chk_buf_ptr_fail_args(mbedtls_ssl_chk_buf_ptr_args *args);
522 
523 static inline int mbedtls_ssl_chk_buf_ptr(const uint8_t *cur,
524                                           const uint8_t *end, size_t need)
525 {
526     if ((cur > end) || (need > (size_t) (end - cur))) {
527         mbedtls_ssl_set_chk_buf_ptr_fail_args(cur, end, need);
528         return 1;
529     }
530     return 0;
531 }
532 #endif /* MBEDTLS_TEST_HOOKS */
533 
534 /**
535  * \brief        This macro checks if the remaining size in a buffer is
536  *               greater or equal than a needed space. If it is not the case,
537  *               it returns an SSL_BUFFER_TOO_SMALL error.
538  *
539  * \param cur    Pointer to the current position in the buffer.
540  * \param end    Pointer to one past the end of the buffer.
541  * \param need   Needed space in bytes.
542  *
543  */
544 #define MBEDTLS_SSL_CHK_BUF_PTR(cur, end, need)                        \
545     do {                                                                 \
546         if (mbedtls_ssl_chk_buf_ptr((cur), (end), (need)) != 0) \
547         {                                                                \
548             return MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL;                  \
549         }                                                                \
550     } while (0)
551 
552 /**
553  * \brief        This macro checks if the remaining length in an input buffer is
554  *               greater or equal than a needed length. If it is not the case, it
555  *               returns #MBEDTLS_ERR_SSL_DECODE_ERROR error and pends a
556  *               #MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR alert message.
557  *
558  *               This is a function-like macro. It is guaranteed to evaluate each
559  *               argument exactly once.
560  *
561  * \param cur    Pointer to the current position in the buffer.
562  * \param end    Pointer to one past the end of the buffer.
563  * \param need   Needed length in bytes.
564  *
565  */
566 #define MBEDTLS_SSL_CHK_BUF_READ_PTR(cur, end, need)                          \
567     do {                                                                        \
568         if (mbedtls_ssl_chk_buf_ptr((cur), (end), (need)) != 0)        \
569         {                                                                       \
570             MBEDTLS_SSL_DEBUG_MSG(1,                                           \
571                                   ("missing input data in %s", __func__));  \
572             MBEDTLS_SSL_PEND_FATAL_ALERT(MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR,   \
573                                          MBEDTLS_ERR_SSL_DECODE_ERROR);       \
574             return MBEDTLS_ERR_SSL_DECODE_ERROR;                             \
575         }                                                                       \
576     } while (0)
577 
578 #ifdef __cplusplus
579 extern "C" {
580 #endif
581 
582 typedef int  mbedtls_ssl_tls_prf_cb(const unsigned char *secret, size_t slen,
583                                     const char *label,
584                                     const unsigned char *random, size_t rlen,
585                                     unsigned char *dstbuf, size_t dlen);
586 
587 /* cipher.h exports the maximum IV, key and block length from
588  * all ciphers enabled in the config, regardless of whether those
589  * ciphers are actually usable in SSL/TLS. Notably, XTS is enabled
590  * in the default configuration and uses 64 Byte keys, but it is
591  * not used for record protection in SSL/TLS.
592  *
593  * In order to prevent unnecessary inflation of key structures,
594  * we introduce SSL-specific variants of the max-{key,block,IV}
595  * macros here which are meant to only take those ciphers into
596  * account which can be negotiated in SSL/TLS.
597  *
598  * Since the current definitions of MBEDTLS_MAX_{KEY|BLOCK|IV}_LENGTH
599  * in cipher.h are rough overapproximations of the real maxima, here
600  * we content ourselves with replicating those overapproximations
601  * for the maximum block and IV length, and excluding XTS from the
602  * computation of the maximum key length. */
603 #define MBEDTLS_SSL_MAX_BLOCK_LENGTH 16
604 #define MBEDTLS_SSL_MAX_IV_LENGTH    16
605 #define MBEDTLS_SSL_MAX_KEY_LENGTH   32
606 
607 /**
608  * \brief   The data structure holding the cryptographic material (key and IV)
609  *          used for record protection in TLS 1.3.
610  */
611 struct mbedtls_ssl_key_set {
612     /*! The key for client->server records. */
613     unsigned char client_write_key[MBEDTLS_SSL_MAX_KEY_LENGTH];
614     /*! The key for server->client records. */
615     unsigned char server_write_key[MBEDTLS_SSL_MAX_KEY_LENGTH];
616     /*! The IV  for client->server records. */
617     unsigned char client_write_iv[MBEDTLS_SSL_MAX_IV_LENGTH];
618     /*! The IV  for server->client records. */
619     unsigned char server_write_iv[MBEDTLS_SSL_MAX_IV_LENGTH];
620 
621     size_t key_len; /*!< The length of client_write_key and
622                      *   server_write_key, in Bytes. */
623     size_t iv_len;  /*!< The length of client_write_iv and
624                      *   server_write_iv, in Bytes. */
625 };
626 typedef struct mbedtls_ssl_key_set mbedtls_ssl_key_set;
627 
628 typedef struct {
629     unsigned char binder_key[MBEDTLS_TLS1_3_MD_MAX_SIZE];
630     unsigned char client_early_traffic_secret[MBEDTLS_TLS1_3_MD_MAX_SIZE];
631     unsigned char early_exporter_master_secret[MBEDTLS_TLS1_3_MD_MAX_SIZE];
632 } mbedtls_ssl_tls13_early_secrets;
633 
634 typedef struct {
635     unsigned char client_handshake_traffic_secret[MBEDTLS_TLS1_3_MD_MAX_SIZE];
636     unsigned char server_handshake_traffic_secret[MBEDTLS_TLS1_3_MD_MAX_SIZE];
637 } mbedtls_ssl_tls13_handshake_secrets;
638 
639 /*
640  * This structure contains the parameters only needed during handshake.
641  */
642 struct mbedtls_ssl_handshake_params {
643     /* Frequently-used boolean or byte fields (placed early to take
644      * advantage of smaller code size for indirect access on Arm Thumb) */
645     uint8_t resume;                     /*!<  session resume indicator*/
646     uint8_t cli_exts;                   /*!< client extension presence*/
647 
648 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
649     uint8_t sni_authmode;               /*!< authmode from SNI callback     */
650 #endif
651 
652 #if defined(MBEDTLS_SSL_SRV_C)
653     /* Flag indicating if a CertificateRequest message has been sent
654      * to the client or not. */
655     uint8_t certificate_request_sent;
656 #if defined(MBEDTLS_SSL_EARLY_DATA)
657     /* Flag indicating if the server has accepted early data or not. */
658     uint8_t early_data_accepted;
659 #endif
660 #endif /* MBEDTLS_SSL_SRV_C */
661 
662 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
663     uint8_t new_session_ticket;         /*!< use NewSessionTicket?    */
664 #endif /* MBEDTLS_SSL_SESSION_TICKETS */
665 
666 #if defined(MBEDTLS_SSL_CLI_C)
667     /** Minimum TLS version to be negotiated.
668      *
669      * It is set up in the ClientHello writing preparation stage and used
670      * throughout the ClientHello writing. Not relevant anymore as soon as
671      * the protocol version has been negotiated thus as soon as the
672      * ServerHello is received.
673      * For a fresh handshake not linked to any previous handshake, it is
674      * equal to the configured minimum minor version to be negotiated. When
675      * renegotiating or resuming a session, it is equal to the previously
676      * negotiated minor version.
677      *
678      * There is no maximum TLS version field in this handshake context.
679      * From the start of the handshake, we need to define a current protocol
680      * version for the record layer which we define as the maximum TLS
681      * version to be negotiated. The `tls_version` field of the SSL context is
682      * used to store this maximum value until it contains the actual
683      * negotiated value.
684      */
685     mbedtls_ssl_protocol_version min_tls_version;
686 #endif
687 
688 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
689     uint8_t extended_ms;                /*!< use Extended Master Secret? */
690 #endif
691 
692 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
693     uint8_t async_in_progress; /*!< an asynchronous operation is in progress */
694 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
695 
696 #if defined(MBEDTLS_SSL_PROTO_DTLS)
697     unsigned char retransmit_state;     /*!<  Retransmission state           */
698 #endif
699 
700 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
701     unsigned char group_list_heap_allocated;
702     unsigned char sig_algs_heap_allocated;
703 #endif
704 
705 #if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
706     uint8_t ecrs_enabled;               /*!< Handshake supports EC restart? */
707     enum { /* this complements ssl->state with info on intra-state operations */
708         ssl_ecrs_none = 0,              /*!< nothing going on (yet)         */
709         ssl_ecrs_crt_verify,            /*!< Certificate: crt_verify()      */
710         ssl_ecrs_ske_start_processing,  /*!< ServerKeyExchange: pk_verify() */
711         ssl_ecrs_cke_ecdh_calc_secret,  /*!< ClientKeyExchange: ECDH step 2 */
712         ssl_ecrs_crt_vrfy_sign,         /*!< CertificateVerify: pk_sign()   */
713     } ecrs_state;                       /*!< current (or last) operation    */
714     mbedtls_x509_crt *ecrs_peer_cert;   /*!< The peer's CRT chain.          */
715     size_t ecrs_n;                      /*!< place for saving a length      */
716 #endif
717 
718     mbedtls_ssl_ciphersuite_t const *ciphersuite_info;
719 
720     MBEDTLS_CHECK_RETURN_CRITICAL
721     int (*update_checksum)(mbedtls_ssl_context *, const unsigned char *, size_t);
722     MBEDTLS_CHECK_RETURN_CRITICAL
723     int (*calc_verify)(const mbedtls_ssl_context *, unsigned char *, size_t *);
724     MBEDTLS_CHECK_RETURN_CRITICAL
725     int (*calc_finished)(mbedtls_ssl_context *, unsigned char *, int);
726     mbedtls_ssl_tls_prf_cb *tls_prf;
727 
728     /*
729      * Handshake specific crypto variables
730      */
731 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
732     uint8_t key_exchange_mode; /*!< Selected key exchange mode */
733 
734     /**
735      * Flag indicating if, in the course of the current handshake, an
736      * HelloRetryRequest message has been sent by the server or received by
737      * the client (<> 0) or not (0).
738      */
739     uint8_t hello_retry_request_flag;
740 
741 #if defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE)
742     /**
743      * Flag indicating if, in the course of the current handshake, a dummy
744      * change_cipher_spec (CCS) record has already been sent. Used to send only
745      * one CCS per handshake while not complicating the handshake state
746      * transitions for that purpose.
747      */
748     uint8_t ccs_sent;
749 #endif
750 
751 #if defined(MBEDTLS_SSL_SRV_C)
752 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
753     uint8_t tls13_kex_modes; /*!< Key exchange modes supported by the client */
754 #endif
755     /** selected_group of key_share extension in HelloRetryRequest message. */
756     uint16_t hrr_selected_group;
757 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
758     uint16_t new_session_tickets_count;         /*!< number of session tickets */
759 #endif
760 #endif /* MBEDTLS_SSL_SRV_C */
761 
762 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
763 
764 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
765     uint16_t received_sig_algs[MBEDTLS_RECEIVED_SIG_ALGS_SIZE];
766 #endif
767 
768 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
769     const uint16_t *group_list;
770     const uint16_t *sig_algs;
771 #endif
772 
773 #if defined(MBEDTLS_DHM_C)
774     mbedtls_dhm_context dhm_ctx;                /*!<  DHM key exchange        */
775 #endif
776 
777 #if !defined(MBEDTLS_USE_PSA_CRYPTO) && \
778     defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED)
779     mbedtls_ecdh_context ecdh_ctx;              /*!<  ECDH key exchange       */
780 #endif /* !MBEDTLS_USE_PSA_CRYPTO &&
781           MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED */
782 
783 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_XXDH_PSA_ANY_ENABLED)
784     psa_key_type_t xxdh_psa_type;
785     size_t xxdh_psa_bits;
786     mbedtls_svc_key_id_t xxdh_psa_privkey;
787     uint8_t xxdh_psa_privkey_is_external;
788     unsigned char xxdh_psa_peerkey[PSA_EXPORT_PUBLIC_KEY_MAX_SIZE];
789     size_t xxdh_psa_peerkey_len;
790 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_XXDH_PSA_ANY_ENABLED */
791 
792 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
793 #if defined(MBEDTLS_USE_PSA_CRYPTO)
794     psa_pake_operation_t psa_pake_ctx;        /*!< EC J-PAKE key exchange */
795     mbedtls_svc_key_id_t psa_pake_password;
796     uint8_t psa_pake_ctx_is_ok;
797 #else
798     mbedtls_ecjpake_context ecjpake_ctx;        /*!< EC J-PAKE key exchange */
799 #endif /* MBEDTLS_USE_PSA_CRYPTO */
800 #if defined(MBEDTLS_SSL_CLI_C)
801     unsigned char *ecjpake_cache;               /*!< Cache for ClientHello ext */
802     size_t ecjpake_cache_len;                   /*!< Length of cached data */
803 #endif
804 #endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
805 
806 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_ANY_ENABLED) || \
807     defined(MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ANY_ALLOWED_ENABLED) || \
808     defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
809     uint16_t *curves_tls_id;      /*!<  List of TLS IDs of supported elliptic curves */
810 #endif
811 
812 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED)
813 #if defined(MBEDTLS_USE_PSA_CRYPTO)
814     mbedtls_svc_key_id_t psk_opaque;            /*!< Opaque PSK from the callback   */
815     uint8_t psk_opaque_is_internal;
816 #else
817     unsigned char *psk;                 /*!<  PSK from the callback         */
818     size_t psk_len;                     /*!<  Length of PSK from callback   */
819 #endif /* MBEDTLS_USE_PSA_CRYPTO */
820     uint16_t    selected_identity;
821 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED */
822 
823 #if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
824     mbedtls_x509_crt_restart_ctx ecrs_ctx;  /*!< restart context            */
825 #endif
826 
827 #if defined(MBEDTLS_X509_CRT_PARSE_C)
828     mbedtls_ssl_key_cert *key_cert;     /*!< chosen key/cert pair (server)  */
829 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
830     mbedtls_ssl_key_cert *sni_key_cert; /*!< key/cert list from SNI         */
831     mbedtls_x509_crt *sni_ca_chain;     /*!< trusted CAs from SNI callback  */
832     mbedtls_x509_crl *sni_ca_crl;       /*!< trusted CAs CRLs from SNI      */
833 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
834 #endif /* MBEDTLS_X509_CRT_PARSE_C */
835 
836 #if defined(MBEDTLS_X509_CRT_PARSE_C) &&        \
837     !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
838     mbedtls_pk_context peer_pubkey;     /*!< The public key from the peer.  */
839 #endif /* MBEDTLS_X509_CRT_PARSE_C && !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
840 
841     struct {
842         size_t total_bytes_buffered; /*!< Cumulative size of heap allocated
843                                       *   buffers used for message buffering. */
844 
845         uint8_t seen_ccs;               /*!< Indicates if a CCS message has
846                                          *   been seen in the current flight. */
847 
848         struct mbedtls_ssl_hs_buffer {
849             unsigned is_valid      : 1;
850             unsigned is_fragmented : 1;
851             unsigned is_complete   : 1;
852             unsigned char *data;
853             size_t data_len;
854         } hs[MBEDTLS_SSL_MAX_BUFFERED_HS];
855 
856         struct {
857             unsigned char *data;
858             size_t len;
859             unsigned epoch;
860         } future_record;
861 
862     } buffering;
863 
864 #if defined(MBEDTLS_SSL_CLI_C) && \
865     (defined(MBEDTLS_SSL_PROTO_DTLS) || \
866     defined(MBEDTLS_SSL_PROTO_TLS1_3))
867     unsigned char *cookie;              /*!< HelloVerifyRequest cookie for DTLS
868                                          *   HelloRetryRequest cookie for TLS 1.3 */
869 #if !defined(MBEDTLS_SSL_PROTO_TLS1_3)
870     /* RFC 6347 page 15
871        ...
872        opaque cookie<0..2^8-1>;
873        ...
874      */
875     uint8_t cookie_len;
876 #else
877     /* RFC 8446 page 39
878        ...
879        opaque cookie<0..2^16-1>;
880        ...
881        If TLS1_3 is enabled, the max length is 2^16 - 1
882      */
883     uint16_t cookie_len;                /*!< DTLS: HelloVerifyRequest cookie length
884                                          *   TLS1_3: HelloRetryRequest cookie length */
885 #endif
886 #endif /* MBEDTLS_SSL_CLI_C &&
887           ( MBEDTLS_SSL_PROTO_DTLS ||
888             MBEDTLS_SSL_PROTO_TLS1_3 ) */
889 #if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_PROTO_DTLS)
890     unsigned char cookie_verify_result; /*!< Srv: flag for sending a cookie */
891 #endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_PROTO_DTLS */
892 
893 #if defined(MBEDTLS_SSL_PROTO_DTLS)
894     unsigned int out_msg_seq;           /*!<  Outgoing handshake sequence number */
895     unsigned int in_msg_seq;            /*!<  Incoming handshake sequence number */
896 
897     uint32_t retransmit_timeout;        /*!<  Current value of timeout       */
898     mbedtls_ssl_flight_item *flight;    /*!<  Current outgoing flight        */
899     mbedtls_ssl_flight_item *cur_msg;   /*!<  Current message in flight      */
900     unsigned char *cur_msg_p;           /*!<  Position in current message    */
901     unsigned int in_flight_start_seq;   /*!<  Minimum message sequence in the
902                                               flight being received          */
903     mbedtls_ssl_transform *alt_transform_out;   /*!<  Alternative transform for
904                                                    resending messages             */
905     unsigned char alt_out_ctr[MBEDTLS_SSL_SEQUENCE_NUMBER_LEN]; /*!<  Alternative record epoch/counter
906                                                                       for resending messages         */
907 
908 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
909     /* The state of CID configuration in this handshake. */
910 
911     uint8_t cid_in_use; /*!< This indicates whether the use of the CID extension
912                          *   has been negotiated. Possible values are
913                          *   #MBEDTLS_SSL_CID_ENABLED and
914                          *   #MBEDTLS_SSL_CID_DISABLED. */
915     unsigned char peer_cid[MBEDTLS_SSL_CID_OUT_LEN_MAX];   /*! The peer's CID */
916     uint8_t peer_cid_len;                                  /*!< The length of
917                                                             *   \c peer_cid.  */
918 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
919 
920     uint16_t mtu;                       /*!<  Handshake mtu, used to fragment outgoing messages */
921 #endif /* MBEDTLS_SSL_PROTO_DTLS */
922 
923     /*
924      * Checksum contexts
925      */
926 #if defined(MBEDTLS_MD_CAN_SHA256)
927 #if defined(MBEDTLS_USE_PSA_CRYPTO)
928     psa_hash_operation_t fin_sha256_psa;
929 #else
930     mbedtls_md_context_t fin_sha256;
931 #endif
932 #endif
933 #if defined(MBEDTLS_MD_CAN_SHA384)
934 #if defined(MBEDTLS_USE_PSA_CRYPTO)
935     psa_hash_operation_t fin_sha384_psa;
936 #else
937     mbedtls_md_context_t fin_sha384;
938 #endif
939 #endif
940 
941 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
942     uint16_t offered_group_id; /* The NamedGroup value for the group
943                                 * that is being used for ephemeral
944                                 * key exchange.
945                                 *
946                                 * On the client: Defaults to the first
947                                 * entry in the client's group list,
948                                 * but can be overwritten by the HRR. */
949 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
950 
951 #if defined(MBEDTLS_SSL_CLI_C)
952     uint8_t client_auth;       /*!< used to check if CertificateRequest has been
953                                     received from server side. If CertificateRequest
954                                     has been received, Certificate and CertificateVerify
955                                     should be sent to server */
956 #endif /* MBEDTLS_SSL_CLI_C */
957     /*
958      * State-local variables used during the processing
959      * of a specific handshake state.
960      */
961     union {
962         /* Outgoing Finished message */
963         struct {
964             uint8_t preparation_done;
965 
966             /* Buffer holding digest of the handshake up to
967              * but excluding the outgoing finished message. */
968             unsigned char digest[MBEDTLS_TLS1_3_MD_MAX_SIZE];
969             size_t digest_len;
970         } finished_out;
971 
972         /* Incoming Finished message */
973         struct {
974             uint8_t preparation_done;
975 
976             /* Buffer holding digest of the handshake up to but
977              * excluding the peer's incoming finished message. */
978             unsigned char digest[MBEDTLS_TLS1_3_MD_MAX_SIZE];
979             size_t digest_len;
980         } finished_in;
981 
982     } state_local;
983 
984     /* End of state-local variables. */
985 
986     unsigned char randbytes[MBEDTLS_CLIENT_HELLO_RANDOM_LEN +
987                             MBEDTLS_SERVER_HELLO_RANDOM_LEN];
988     /*!<  random bytes            */
989 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
990     unsigned char premaster[MBEDTLS_PREMASTER_SIZE];
991     /*!<  premaster secret        */
992     size_t pmslen;                      /*!<  premaster length        */
993 #endif
994 
995 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
996     uint32_t sent_extensions;       /*!< extensions sent by endpoint */
997     uint32_t received_extensions;   /*!< extensions received by endpoint */
998 
999 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
1000     unsigned char certificate_request_context_len;
1001     unsigned char *certificate_request_context;
1002 #endif
1003 
1004     /** TLS 1.3 transform for encrypted handshake messages. */
1005     mbedtls_ssl_transform *transform_handshake;
1006     union {
1007         unsigned char early[MBEDTLS_TLS1_3_MD_MAX_SIZE];
1008         unsigned char handshake[MBEDTLS_TLS1_3_MD_MAX_SIZE];
1009         unsigned char app[MBEDTLS_TLS1_3_MD_MAX_SIZE];
1010     } tls13_master_secrets;
1011 
1012     mbedtls_ssl_tls13_handshake_secrets tls13_hs_secrets;
1013 #if defined(MBEDTLS_SSL_EARLY_DATA)
1014     /** TLS 1.3 transform for early data and handshake messages. */
1015     mbedtls_ssl_transform *transform_earlydata;
1016 #endif
1017 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1018 
1019 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
1020     /** Asynchronous operation context. This field is meant for use by the
1021      * asynchronous operation callbacks (mbedtls_ssl_config::f_async_sign_start,
1022      * mbedtls_ssl_config::f_async_decrypt_start,
1023      * mbedtls_ssl_config::f_async_resume, mbedtls_ssl_config::f_async_cancel).
1024      * The library does not use it internally. */
1025     void *user_async_ctx;
1026 #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
1027 
1028 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
1029     const unsigned char *sni_name;      /*!< raw SNI                        */
1030     size_t sni_name_len;                /*!< raw SNI len                    */
1031 #if defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED)
1032     const mbedtls_x509_crt *dn_hints;   /*!< acceptable client cert issuers */
1033 #endif
1034 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
1035 };
1036 
1037 typedef struct mbedtls_ssl_hs_buffer mbedtls_ssl_hs_buffer;
1038 
1039 /*
1040  * Representation of decryption/encryption transformations on records
1041  *
1042  * There are the following general types of record transformations:
1043  * - Stream transformations (TLS versions == 1.2 only)
1044  *   Transformation adding a MAC and applying a stream-cipher
1045  *   to the authenticated message.
1046  * - CBC block cipher transformations ([D]TLS versions == 1.2 only)
1047  *   For TLS 1.2, no IV is generated at key extraction time, but every
1048  *   encrypted record is explicitly prefixed by the IV with which it was
1049  *   encrypted.
1050  * - AEAD transformations ([D]TLS versions == 1.2 only)
1051  *   These come in two fundamentally different versions, the first one
1052  *   used in TLS 1.2, excluding ChaChaPoly ciphersuites, and the second
1053  *   one used for ChaChaPoly ciphersuites in TLS 1.2 as well as for TLS 1.3.
1054  *   In the first transformation, the IV to be used for a record is obtained
1055  *   as the concatenation of an explicit, static 4-byte IV and the 8-byte
1056  *   record sequence number, and explicitly prepending this sequence number
1057  *   to the encrypted record. In contrast, in the second transformation
1058  *   the IV is obtained by XOR'ing a static IV obtained at key extraction
1059  *   time with the 8-byte record sequence number, without prepending the
1060  *   latter to the encrypted record.
1061  *
1062  * Additionally, DTLS 1.2 + CID as well as TLS 1.3 use an inner plaintext
1063  * which allows to add flexible length padding and to hide a record's true
1064  * content type.
1065  *
1066  * In addition to type and version, the following parameters are relevant:
1067  * - The symmetric cipher algorithm to be used.
1068  * - The (static) encryption/decryption keys for the cipher.
1069  * - For stream/CBC, the type of message digest to be used.
1070  * - For stream/CBC, (static) encryption/decryption keys for the digest.
1071  * - For AEAD transformations, the size (potentially 0) of an explicit,
1072  *   random initialization vector placed in encrypted records.
1073  * - For some transformations (currently AEAD) an implicit IV. It is static
1074  *   and (if present) is combined with the explicit IV in a transformation-
1075  *   -dependent way (e.g. appending in TLS 1.2 and XOR'ing in TLS 1.3).
1076  * - For stream/CBC, a flag determining the order of encryption and MAC.
1077  * - The details of the transformation depend on the SSL/TLS version.
1078  * - The length of the authentication tag.
1079  *
1080  * The struct below refines this abstract view as follows:
1081  * - The cipher underlying the transformation is managed in
1082  *   cipher contexts cipher_ctx_{enc/dec}, which must have the
1083  *   same cipher type. The mode of these cipher contexts determines
1084  *   the type of the transformation in the sense above: e.g., if
1085  *   the type is MBEDTLS_CIPHER_AES_256_CBC resp. MBEDTLS_CIPHER_AES_192_GCM
1086  *   then the transformation has type CBC resp. AEAD.
1087  * - The cipher keys are never stored explicitly but
1088  *   are maintained within cipher_ctx_{enc/dec}.
1089  * - For stream/CBC transformations, the message digest contexts
1090  *   used for the MAC's are stored in md_ctx_{enc/dec}. These contexts
1091  *   are unused for AEAD transformations.
1092  * - For stream/CBC transformations, the MAC keys are not stored explicitly
1093  *   but maintained within md_ctx_{enc/dec}.
1094  * - The mac_enc and mac_dec fields are unused for EAD transformations.
1095  * - For transformations using an implicit IV maintained within
1096  *   the transformation context, its contents are stored within
1097  *   iv_{enc/dec}.
1098  * - The value of ivlen indicates the length of the IV.
1099  *   This is redundant in case of stream/CBC transformations
1100  *   which always use 0 resp. the cipher's block length as the
1101  *   IV length, but is needed for AEAD ciphers and may be
1102  *   different from the underlying cipher's block length
1103  *   in this case.
1104  * - The field fixed_ivlen is nonzero for AEAD transformations only
1105  *   and indicates the length of the static part of the IV which is
1106  *   constant throughout the communication, and which is stored in
1107  *   the first fixed_ivlen bytes of the iv_{enc/dec} arrays.
1108  * - tls_version denotes the 2-byte TLS version
1109  * - For stream/CBC transformations, maclen denotes the length of the
1110  *   authentication tag, while taglen is unused and 0.
1111  * - For AEAD transformations, taglen denotes the length of the
1112  *   authentication tag, while maclen is unused and 0.
1113  * - For CBC transformations, encrypt_then_mac determines the
1114  *   order of encryption and authentication. This field is unused
1115  *   in other transformations.
1116  *
1117  */
1118 struct mbedtls_ssl_transform {
1119     /*
1120      * Session specific crypto layer
1121      */
1122     size_t minlen;                      /*!<  min. ciphertext length  */
1123     size_t ivlen;                       /*!<  IV length               */
1124     size_t fixed_ivlen;                 /*!<  Fixed part of IV (AEAD) */
1125     size_t maclen;                      /*!<  MAC(CBC) len            */
1126     size_t taglen;                      /*!<  TAG(AEAD) len           */
1127 
1128     unsigned char iv_enc[16];           /*!<  IV (encryption)         */
1129     unsigned char iv_dec[16];           /*!<  IV (decryption)         */
1130 
1131 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC)
1132 
1133 #if defined(MBEDTLS_USE_PSA_CRYPTO)
1134     mbedtls_svc_key_id_t psa_mac_enc;           /*!<  MAC (encryption)        */
1135     mbedtls_svc_key_id_t psa_mac_dec;           /*!<  MAC (decryption)        */
1136     psa_algorithm_t psa_mac_alg;                /*!<  psa MAC algorithm       */
1137 #else
1138     mbedtls_md_context_t md_ctx_enc;            /*!<  MAC (encryption)        */
1139     mbedtls_md_context_t md_ctx_dec;            /*!<  MAC (decryption)        */
1140 #endif /* MBEDTLS_USE_PSA_CRYPTO */
1141 
1142 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
1143     int encrypt_then_mac;       /*!< flag for EtM activation                */
1144 #endif
1145 
1146 #endif /* MBEDTLS_SSL_SOME_SUITES_USE_MAC */
1147 
1148     mbedtls_ssl_protocol_version tls_version;
1149 
1150 #if defined(MBEDTLS_USE_PSA_CRYPTO)
1151     mbedtls_svc_key_id_t psa_key_enc;           /*!<  psa encryption key      */
1152     mbedtls_svc_key_id_t psa_key_dec;           /*!<  psa decryption key      */
1153     psa_algorithm_t psa_alg;                    /*!<  psa algorithm           */
1154 #else
1155     mbedtls_cipher_context_t cipher_ctx_enc;    /*!<  encryption context      */
1156     mbedtls_cipher_context_t cipher_ctx_dec;    /*!<  decryption context      */
1157 #endif /* MBEDTLS_USE_PSA_CRYPTO */
1158 
1159 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1160     uint8_t in_cid_len;
1161     uint8_t out_cid_len;
1162     unsigned char in_cid[MBEDTLS_SSL_CID_IN_LEN_MAX];
1163     unsigned char out_cid[MBEDTLS_SSL_CID_OUT_LEN_MAX];
1164 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1165 
1166 #if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION)
1167     /* We need the Hello random bytes in order to re-derive keys from the
1168      * Master Secret and other session info,
1169      * see ssl_tls12_populate_transform() */
1170     unsigned char randbytes[MBEDTLS_SERVER_HELLO_RANDOM_LEN +
1171                             MBEDTLS_CLIENT_HELLO_RANDOM_LEN];
1172     /*!< ServerHello.random+ClientHello.random */
1173 #endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */
1174 };
1175 
1176 /*
1177  * Return 1 if the transform uses an AEAD cipher, 0 otherwise.
1178  * Equivalently, return 0 if a separate MAC is used, 1 otherwise.
1179  */
1180 static inline int mbedtls_ssl_transform_uses_aead(
1181     const mbedtls_ssl_transform *transform)
1182 {
1183 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC)
1184     return transform->maclen == 0 && transform->taglen != 0;
1185 #else
1186     (void) transform;
1187     return 1;
1188 #endif
1189 }
1190 
1191 /*
1192  * Internal representation of record frames
1193  *
1194  * Instances come in two flavors:
1195  * (1) Encrypted
1196  *     These always have data_offset = 0
1197  * (2) Unencrypted
1198  *     These have data_offset set to the amount of
1199  *     pre-expansion during record protection. Concretely,
1200  *     this is the length of the fixed part of the explicit IV
1201  *     used for encryption, or 0 if no explicit IV is used
1202  *     (e.g. for stream ciphers).
1203  *
1204  * The reason for the data_offset in the unencrypted case
1205  * is to allow for in-place conversion of an unencrypted to
1206  * an encrypted record. If the offset wasn't included, the
1207  * encrypted content would need to be shifted afterwards to
1208  * make space for the fixed IV.
1209  *
1210  */
1211 #if MBEDTLS_SSL_CID_OUT_LEN_MAX > MBEDTLS_SSL_CID_IN_LEN_MAX
1212 #define MBEDTLS_SSL_CID_LEN_MAX MBEDTLS_SSL_CID_OUT_LEN_MAX
1213 #else
1214 #define MBEDTLS_SSL_CID_LEN_MAX MBEDTLS_SSL_CID_IN_LEN_MAX
1215 #endif
1216 
1217 typedef struct {
1218     uint8_t ctr[MBEDTLS_SSL_SEQUENCE_NUMBER_LEN];  /* In TLS:  The implicit record sequence number.
1219                                                     * In DTLS: The 2-byte epoch followed by
1220                                                     *          the 6-byte sequence number.
1221                                                     * This is stored as a raw big endian byte array
1222                                                     * as opposed to a uint64_t because we rarely
1223                                                     * need to perform arithmetic on this, but do
1224                                                     * need it as a Byte array for the purpose of
1225                                                     * MAC computations.                             */
1226     uint8_t type;           /* The record content type.                      */
1227     uint8_t ver[2];         /* SSL/TLS version as present on the wire.
1228                              * Convert to internal presentation of versions
1229                              * using mbedtls_ssl_read_version() and
1230                              * mbedtls_ssl_write_version().
1231                              * Keep wire-format for MAC computations.        */
1232 
1233     unsigned char *buf;     /* Memory buffer enclosing the record content    */
1234     size_t buf_len;         /* Buffer length                                 */
1235     size_t data_offset;     /* Offset of record content                      */
1236     size_t data_len;        /* Length of record content                      */
1237 
1238 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
1239     uint8_t cid_len;        /* Length of the CID (0 if not present)          */
1240     unsigned char cid[MBEDTLS_SSL_CID_LEN_MAX];   /* The CID                 */
1241 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
1242 } mbedtls_record;
1243 
1244 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1245 /*
1246  * List of certificate + private key pairs
1247  */
1248 struct mbedtls_ssl_key_cert {
1249     mbedtls_x509_crt *cert;                 /*!< cert                       */
1250     mbedtls_pk_context *key;                /*!< private key                */
1251     mbedtls_ssl_key_cert *next;             /*!< next key/cert pair         */
1252 };
1253 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1254 
1255 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1256 /*
1257  * List of handshake messages kept around for resending
1258  */
1259 struct mbedtls_ssl_flight_item {
1260     unsigned char *p;       /*!< message, including handshake headers   */
1261     size_t len;             /*!< length of p                            */
1262     unsigned char type;     /*!< type of the message: handshake or CCS  */
1263     mbedtls_ssl_flight_item *next;  /*!< next handshake message(s)              */
1264 };
1265 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1266 
1267 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
1268 /**
1269  * \brief Given an SSL context and its associated configuration, write the TLS
1270  *        1.2 specific extensions of the ClientHello message.
1271  *
1272  * \param[in]   ssl     SSL context
1273  * \param[in]   buf     Base address of the buffer where to write the extensions
1274  * \param[in]   end     End address of the buffer where to write the extensions
1275  * \param       uses_ec Whether one proposed ciphersuite uses an elliptic curve
1276  *                      (<> 0) or not ( 0 ).
1277  * \param[out]  out_len Length of the data written into the buffer \p buf
1278  */
1279 MBEDTLS_CHECK_RETURN_CRITICAL
1280 int mbedtls_ssl_tls12_write_client_hello_exts(mbedtls_ssl_context *ssl,
1281                                               unsigned char *buf,
1282                                               const unsigned char *end,
1283                                               int uses_ec,
1284                                               size_t *out_len);
1285 #endif
1286 
1287 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
1288     defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
1289 
1290 /**
1291  * \brief Find the preferred hash for a given signature algorithm.
1292  *
1293  * \param[in]   ssl     SSL context
1294  * \param[in]   sig_alg A signature algorithm identifier as defined in the
1295  *                      TLS 1.2 SignatureAlgorithm enumeration.
1296  *
1297  * \return  The preferred hash algorithm for \p sig_alg. It is a hash algorithm
1298  *          identifier as defined in the TLS 1.2 HashAlgorithm enumeration.
1299  */
1300 unsigned int mbedtls_ssl_tls12_get_preferred_hash_for_sig_alg(
1301     mbedtls_ssl_context *ssl,
1302     unsigned int sig_alg);
1303 
1304 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 &&
1305           MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
1306 
1307 /**
1308  * \brief           Free referenced items in an SSL transform context and clear
1309  *                  memory
1310  *
1311  * \param transform SSL transform context
1312  */
1313 void mbedtls_ssl_transform_free(mbedtls_ssl_transform *transform);
1314 
1315 /**
1316  * \brief           Free referenced items in an SSL handshake context and clear
1317  *                  memory
1318  *
1319  * \param ssl       SSL context
1320  */
1321 void mbedtls_ssl_handshake_free(mbedtls_ssl_context *ssl);
1322 
1323 /* set inbound transform of ssl context */
1324 void mbedtls_ssl_set_inbound_transform(mbedtls_ssl_context *ssl,
1325                                        mbedtls_ssl_transform *transform);
1326 
1327 /* set outbound transform of ssl context */
1328 void mbedtls_ssl_set_outbound_transform(mbedtls_ssl_context *ssl,
1329                                         mbedtls_ssl_transform *transform);
1330 
1331 MBEDTLS_CHECK_RETURN_CRITICAL
1332 int mbedtls_ssl_handshake_client_step(mbedtls_ssl_context *ssl);
1333 MBEDTLS_CHECK_RETURN_CRITICAL
1334 int mbedtls_ssl_handshake_server_step(mbedtls_ssl_context *ssl);
1335 void mbedtls_ssl_handshake_wrapup(mbedtls_ssl_context *ssl);
1336 static inline void mbedtls_ssl_handshake_set_state(mbedtls_ssl_context *ssl,
1337                                                    mbedtls_ssl_states state)
1338 {
1339     ssl->state = (int) state;
1340 }
1341 
1342 MBEDTLS_CHECK_RETURN_CRITICAL
1343 int mbedtls_ssl_send_fatal_handshake_failure(mbedtls_ssl_context *ssl);
1344 
1345 MBEDTLS_CHECK_RETURN_CRITICAL
1346 int mbedtls_ssl_reset_checksum(mbedtls_ssl_context *ssl);
1347 
1348 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
1349 MBEDTLS_CHECK_RETURN_CRITICAL
1350 int mbedtls_ssl_derive_keys(mbedtls_ssl_context *ssl);
1351 #endif /* MBEDTLS_SSL_PROTO_TLS1_2  */
1352 
1353 MBEDTLS_CHECK_RETURN_CRITICAL
1354 int mbedtls_ssl_handle_message_type(mbedtls_ssl_context *ssl);
1355 MBEDTLS_CHECK_RETURN_CRITICAL
1356 int mbedtls_ssl_prepare_handshake_record(mbedtls_ssl_context *ssl);
1357 MBEDTLS_CHECK_RETURN_CRITICAL
1358 int mbedtls_ssl_update_handshake_status(mbedtls_ssl_context *ssl);
1359 
1360 /**
1361  * \brief       Update record layer
1362  *
1363  *              This function roughly separates the implementation
1364  *              of the logic of (D)TLS from the implementation
1365  *              of the secure transport.
1366  *
1367  * \param  ssl              The SSL context to use.
1368  * \param  update_hs_digest This indicates if the handshake digest
1369  *                          should be automatically updated in case
1370  *                          a handshake message is found.
1371  *
1372  * \return      0 or non-zero error code.
1373  *
1374  * \note        A clarification on what is called 'record layer' here
1375  *              is in order, as many sensible definitions are possible:
1376  *
1377  *              The record layer takes as input an untrusted underlying
1378  *              transport (stream or datagram) and transforms it into
1379  *              a serially multiplexed, secure transport, which
1380  *              conceptually provides the following:
1381  *
1382  *              (1) Three datagram based, content-agnostic transports
1383  *                  for handshake, alert and CCS messages.
1384  *              (2) One stream- or datagram-based transport
1385  *                  for application data.
1386  *              (3) Functionality for changing the underlying transform
1387  *                  securing the contents.
1388  *
1389  *              The interface to this functionality is given as follows:
1390  *
1391  *              a Updating
1392  *                [Currently implemented by mbedtls_ssl_read_record]
1393  *
1394  *                Check if and on which of the four 'ports' data is pending:
1395  *                Nothing, a controlling datagram of type (1), or application
1396  *                data (2). In any case data is present, internal buffers
1397  *                provide access to the data for the user to process it.
1398  *                Consumption of type (1) datagrams is done automatically
1399  *                on the next update, invalidating that the internal buffers
1400  *                for previous datagrams, while consumption of application
1401  *                data (2) is user-controlled.
1402  *
1403  *              b Reading of application data
1404  *                [Currently manual adaption of ssl->in_offt pointer]
1405  *
1406  *                As mentioned in the last paragraph, consumption of data
1407  *                is different from the automatic consumption of control
1408  *                datagrams (1) because application data is treated as a stream.
1409  *
1410  *              c Tracking availability of application data
1411  *                [Currently manually through decreasing ssl->in_msglen]
1412  *
1413  *                For efficiency and to retain datagram semantics for
1414  *                application data in case of DTLS, the record layer
1415  *                provides functionality for checking how much application
1416  *                data is still available in the internal buffer.
1417  *
1418  *              d Changing the transformation securing the communication.
1419  *
1420  *              Given an opaque implementation of the record layer in the
1421  *              above sense, it should be possible to implement the logic
1422  *              of (D)TLS on top of it without the need to know anything
1423  *              about the record layer's internals. This is done e.g.
1424  *              in all the handshake handling functions, and in the
1425  *              application data reading function mbedtls_ssl_read.
1426  *
1427  * \note        The above tries to give a conceptual picture of the
1428  *              record layer, but the current implementation deviates
1429  *              from it in some places. For example, our implementation of
1430  *              the update functionality through mbedtls_ssl_read_record
1431  *              discards datagrams depending on the current state, which
1432  *              wouldn't fall under the record layer's responsibility
1433  *              following the above definition.
1434  *
1435  */
1436 MBEDTLS_CHECK_RETURN_CRITICAL
1437 int mbedtls_ssl_read_record(mbedtls_ssl_context *ssl,
1438                             unsigned update_hs_digest);
1439 MBEDTLS_CHECK_RETURN_CRITICAL
1440 int mbedtls_ssl_fetch_input(mbedtls_ssl_context *ssl, size_t nb_want);
1441 
1442 /*
1443  * Write handshake message header
1444  */
1445 MBEDTLS_CHECK_RETURN_CRITICAL
1446 int mbedtls_ssl_start_handshake_msg(mbedtls_ssl_context *ssl, unsigned char hs_type,
1447                                     unsigned char **buf, size_t *buf_len);
1448 
1449 MBEDTLS_CHECK_RETURN_CRITICAL
1450 int mbedtls_ssl_write_handshake_msg_ext(mbedtls_ssl_context *ssl,
1451                                         int update_checksum,
1452                                         int force_flush);
1453 static inline int mbedtls_ssl_write_handshake_msg(mbedtls_ssl_context *ssl)
1454 {
1455     return mbedtls_ssl_write_handshake_msg_ext(ssl, 1 /* update checksum */, 1 /* force flush */);
1456 }
1457 
1458 /*
1459  * Write handshake message tail
1460  */
1461 MBEDTLS_CHECK_RETURN_CRITICAL
1462 int mbedtls_ssl_finish_handshake_msg(mbedtls_ssl_context *ssl,
1463                                      size_t buf_len, size_t msg_len);
1464 
1465 MBEDTLS_CHECK_RETURN_CRITICAL
1466 int mbedtls_ssl_write_record(mbedtls_ssl_context *ssl, int force_flush);
1467 MBEDTLS_CHECK_RETURN_CRITICAL
1468 int mbedtls_ssl_flush_output(mbedtls_ssl_context *ssl);
1469 
1470 MBEDTLS_CHECK_RETURN_CRITICAL
1471 int mbedtls_ssl_parse_certificate(mbedtls_ssl_context *ssl);
1472 MBEDTLS_CHECK_RETURN_CRITICAL
1473 int mbedtls_ssl_write_certificate(mbedtls_ssl_context *ssl);
1474 
1475 MBEDTLS_CHECK_RETURN_CRITICAL
1476 int mbedtls_ssl_parse_change_cipher_spec(mbedtls_ssl_context *ssl);
1477 MBEDTLS_CHECK_RETURN_CRITICAL
1478 int mbedtls_ssl_write_change_cipher_spec(mbedtls_ssl_context *ssl);
1479 
1480 MBEDTLS_CHECK_RETURN_CRITICAL
1481 int mbedtls_ssl_parse_finished(mbedtls_ssl_context *ssl);
1482 MBEDTLS_CHECK_RETURN_CRITICAL
1483 int mbedtls_ssl_write_finished(mbedtls_ssl_context *ssl);
1484 
1485 void mbedtls_ssl_optimize_checksum(mbedtls_ssl_context *ssl,
1486                                    const mbedtls_ssl_ciphersuite_t *ciphersuite_info);
1487 
1488 /*
1489  * Update checksum of handshake messages.
1490  */
1491 MBEDTLS_CHECK_RETURN_CRITICAL
1492 int mbedtls_ssl_add_hs_msg_to_checksum(mbedtls_ssl_context *ssl,
1493                                        unsigned hs_type,
1494                                        unsigned char const *msg,
1495                                        size_t msg_len);
1496 
1497 MBEDTLS_CHECK_RETURN_CRITICAL
1498 int mbedtls_ssl_add_hs_hdr_to_checksum(mbedtls_ssl_context *ssl,
1499                                        unsigned hs_type,
1500                                        size_t total_hs_len);
1501 
1502 #if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
1503 #if !defined(MBEDTLS_USE_PSA_CRYPTO)
1504 MBEDTLS_CHECK_RETURN_CRITICAL
1505 int mbedtls_ssl_psk_derive_premaster(mbedtls_ssl_context *ssl,
1506                                      mbedtls_key_exchange_type_t key_ex);
1507 #endif /* !MBEDTLS_USE_PSA_CRYPTO */
1508 #endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
1509 
1510 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED)
1511 #if defined(MBEDTLS_SSL_CLI_C) || defined(MBEDTLS_SSL_SRV_C)
1512 MBEDTLS_CHECK_RETURN_CRITICAL
1513 int mbedtls_ssl_conf_has_static_psk(mbedtls_ssl_config const *conf);
1514 #endif
1515 #if defined(MBEDTLS_USE_PSA_CRYPTO)
1516 /**
1517  * Get the first defined opaque PSK by order of precedence:
1518  * 1. handshake PSK set by \c mbedtls_ssl_set_hs_psk_opaque() in the PSK
1519  *    callback
1520  * 2. static PSK configured by \c mbedtls_ssl_conf_psk_opaque()
1521  * Return an opaque PSK
1522  */
1523 static inline mbedtls_svc_key_id_t mbedtls_ssl_get_opaque_psk(
1524     const mbedtls_ssl_context *ssl)
1525 {
1526     if (!mbedtls_svc_key_id_is_null(ssl->handshake->psk_opaque)) {
1527         return ssl->handshake->psk_opaque;
1528     }
1529 
1530     if (!mbedtls_svc_key_id_is_null(ssl->conf->psk_opaque)) {
1531         return ssl->conf->psk_opaque;
1532     }
1533 
1534     return MBEDTLS_SVC_KEY_ID_INIT;
1535 }
1536 #else
1537 /**
1538  * Get the first defined PSK by order of precedence:
1539  * 1. handshake PSK set by \c mbedtls_ssl_set_hs_psk() in the PSK callback
1540  * 2. static PSK configured by \c mbedtls_ssl_conf_psk()
1541  * Return a code and update the pair (PSK, PSK length) passed to this function
1542  */
1543 static inline int mbedtls_ssl_get_psk(const mbedtls_ssl_context *ssl,
1544                                       const unsigned char **psk, size_t *psk_len)
1545 {
1546     if (ssl->handshake->psk != NULL && ssl->handshake->psk_len > 0) {
1547         *psk = ssl->handshake->psk;
1548         *psk_len = ssl->handshake->psk_len;
1549     } else if (ssl->conf->psk != NULL && ssl->conf->psk_len > 0) {
1550         *psk = ssl->conf->psk;
1551         *psk_len = ssl->conf->psk_len;
1552     } else {
1553         *psk = NULL;
1554         *psk_len = 0;
1555         return MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED;
1556     }
1557 
1558     return 0;
1559 }
1560 #endif /* MBEDTLS_USE_PSA_CRYPTO */
1561 
1562 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED */
1563 
1564 #if defined(MBEDTLS_PK_C)
1565 unsigned char mbedtls_ssl_sig_from_pk(mbedtls_pk_context *pk);
1566 unsigned char mbedtls_ssl_sig_from_pk_alg(mbedtls_pk_type_t type);
1567 mbedtls_pk_type_t mbedtls_ssl_pk_alg_from_sig(unsigned char sig);
1568 #endif
1569 
1570 mbedtls_md_type_t mbedtls_ssl_md_alg_from_hash(unsigned char hash);
1571 unsigned char mbedtls_ssl_hash_from_md_alg(int md);
1572 
1573 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
1574 MBEDTLS_CHECK_RETURN_CRITICAL
1575 int mbedtls_ssl_set_calc_verify_md(mbedtls_ssl_context *ssl, int md);
1576 #endif
1577 
1578 MBEDTLS_CHECK_RETURN_CRITICAL
1579 int mbedtls_ssl_check_curve_tls_id(const mbedtls_ssl_context *ssl, uint16_t tls_id);
1580 #if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
1581 MBEDTLS_CHECK_RETURN_CRITICAL
1582 int mbedtls_ssl_check_curve(const mbedtls_ssl_context *ssl, mbedtls_ecp_group_id grp_id);
1583 #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
1584 
1585 /**
1586  * \brief Return PSA EC info for the specified TLS ID.
1587  *
1588  * \param tls_id    The TLS ID to look for
1589  * \param type      If the TLD ID is supported, then proper \c psa_key_type_t
1590  *                  value is returned here. Can be NULL.
1591  * \param bits      If the TLD ID is supported, then proper bit size is returned
1592  *                  here. Can be NULL.
1593  * \return          PSA_SUCCESS if the TLS ID is supported,
1594  *                  PSA_ERROR_NOT_SUPPORTED otherwise
1595  *
1596  * \note            If either \c family or \c bits parameters are NULL, then
1597  *                  the corresponding value is not returned.
1598  *                  The function can be called with both parameters as NULL
1599  *                  simply to check if a specific TLS ID is supported.
1600  */
1601 int mbedtls_ssl_get_psa_curve_info_from_tls_id(uint16_t tls_id,
1602                                                psa_key_type_t *type,
1603                                                size_t *bits);
1604 
1605 /**
1606  * \brief Return \c mbedtls_ecp_group_id for the specified TLS ID.
1607  *
1608  * \param tls_id    The TLS ID to look for
1609  * \return          Proper \c mbedtls_ecp_group_id if the TLS ID is supported,
1610  *                  or MBEDTLS_ECP_DP_NONE otherwise
1611  */
1612 mbedtls_ecp_group_id mbedtls_ssl_get_ecp_group_id_from_tls_id(uint16_t tls_id);
1613 
1614 /**
1615  * \brief Return TLS ID for the specified \c mbedtls_ecp_group_id.
1616  *
1617  * \param grp_id    The \c mbedtls_ecp_group_id ID to look for
1618  * \return          Proper TLS ID if the \c mbedtls_ecp_group_id is supported,
1619  *                  or 0 otherwise
1620  */
1621 uint16_t mbedtls_ssl_get_tls_id_from_ecp_group_id(mbedtls_ecp_group_id grp_id);
1622 
1623 #if defined(MBEDTLS_DEBUG_C)
1624 /**
1625  * \brief Return EC's name for the specified TLS ID.
1626  *
1627  * \param tls_id    The TLS ID to look for
1628  * \return          A pointer to a const string with the proper name. If TLS
1629  *                  ID is not supported, a NULL pointer is returned instead.
1630  */
1631 const char *mbedtls_ssl_get_curve_name_from_tls_id(uint16_t tls_id);
1632 #endif
1633 
1634 #if defined(MBEDTLS_SSL_DTLS_SRTP)
1635 static inline mbedtls_ssl_srtp_profile mbedtls_ssl_check_srtp_profile_value
1636     (const uint16_t srtp_profile_value)
1637 {
1638     switch (srtp_profile_value) {
1639         case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80:
1640         case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32:
1641         case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80:
1642         case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32:
1643             return srtp_profile_value;
1644         default: break;
1645     }
1646     return MBEDTLS_TLS_SRTP_UNSET;
1647 }
1648 #endif
1649 
1650 #if defined(MBEDTLS_X509_CRT_PARSE_C)
1651 static inline mbedtls_pk_context *mbedtls_ssl_own_key(mbedtls_ssl_context *ssl)
1652 {
1653     mbedtls_ssl_key_cert *key_cert;
1654 
1655     if (ssl->handshake != NULL && ssl->handshake->key_cert != NULL) {
1656         key_cert = ssl->handshake->key_cert;
1657     } else {
1658         key_cert = ssl->conf->key_cert;
1659     }
1660 
1661     return key_cert == NULL ? NULL : key_cert->key;
1662 }
1663 
1664 static inline mbedtls_x509_crt *mbedtls_ssl_own_cert(mbedtls_ssl_context *ssl)
1665 {
1666     mbedtls_ssl_key_cert *key_cert;
1667 
1668     if (ssl->handshake != NULL && ssl->handshake->key_cert != NULL) {
1669         key_cert = ssl->handshake->key_cert;
1670     } else {
1671         key_cert = ssl->conf->key_cert;
1672     }
1673 
1674     return key_cert == NULL ? NULL : key_cert->cert;
1675 }
1676 
1677 /*
1678  * Verify a certificate.
1679  *
1680  * [in/out] ssl: misc. things read
1681  *               ssl->session_negotiate->verify_result updated
1682  * [in] authmode: one of MBEDTLS_SSL_VERIFY_{NONE,OPTIONAL,REQUIRED}
1683  * [in] chain: the certificate chain to verify (ie the peer's chain)
1684  * [in] ciphersuite_info: For TLS 1.2, this session's ciphersuite;
1685  *                        for TLS 1.3, may be left NULL.
1686  * [in] rs_ctx: restart context if restartable ECC is in use;
1687  *              leave NULL for no restartable behaviour.
1688  *
1689  * Return:
1690  * - 0 if the handshake should continue. Depending on the
1691  *   authmode it means:
1692  *   - REQUIRED: the certificate was found to be valid, trusted & acceptable.
1693  *     ssl->session_negotiate->verify_result is 0.
1694  *   - OPTIONAL: the certificate may or may not be acceptable, but
1695  *     ssl->session_negotiate->verify_result was updated with the result.
1696  *   - NONE: the certificate wasn't even checked.
1697  * - MBEDTLS_ERR_X509_CERT_VERIFY_FAILED or MBEDTLS_ERR_SSL_BAD_CERTIFICATE if
1698  *   the certificate was found to be invalid/untrusted/unacceptable and the
1699  *   handshake should be aborted (can only happen with REQUIRED).
1700  * - another error code if another error happened (out-of-memory, etc.)
1701  */
1702 MBEDTLS_CHECK_RETURN_CRITICAL
1703 int mbedtls_ssl_verify_certificate(mbedtls_ssl_context *ssl,
1704                                    int authmode,
1705                                    mbedtls_x509_crt *chain,
1706                                    const mbedtls_ssl_ciphersuite_t *ciphersuite_info,
1707                                    void *rs_ctx);
1708 
1709 /*
1710  * Check usage of a certificate wrt usage extensions:
1711  * keyUsage and extendedKeyUsage.
1712  * (Note: nSCertType is deprecated and not standard, we don't check it.)
1713  *
1714  * Note: if tls_version is 1.3, ciphersuite is ignored and can be NULL.
1715  *
1716  * Note: recv_endpoint is the receiver's endpoint.
1717  *
1718  * Return 0 if everything is OK, -1 if not.
1719  */
1720 MBEDTLS_CHECK_RETURN_CRITICAL
1721 int mbedtls_ssl_check_cert_usage(const mbedtls_x509_crt *cert,
1722                                  const mbedtls_ssl_ciphersuite_t *ciphersuite,
1723                                  int recv_endpoint,
1724                                  mbedtls_ssl_protocol_version tls_version,
1725                                  uint32_t *flags);
1726 #endif /* MBEDTLS_X509_CRT_PARSE_C */
1727 
1728 void mbedtls_ssl_write_version(unsigned char version[2], int transport,
1729                                mbedtls_ssl_protocol_version tls_version);
1730 uint16_t mbedtls_ssl_read_version(const unsigned char version[2],
1731                                   int transport);
1732 
1733 static inline size_t mbedtls_ssl_in_hdr_len(const mbedtls_ssl_context *ssl)
1734 {
1735 #if !defined(MBEDTLS_SSL_PROTO_DTLS)
1736     ((void) ssl);
1737 #endif
1738 
1739 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1740     if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM) {
1741         return 13;
1742     } else
1743 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1744     {
1745         return 5;
1746     }
1747 }
1748 
1749 static inline size_t mbedtls_ssl_out_hdr_len(const mbedtls_ssl_context *ssl)
1750 {
1751     return (size_t) (ssl->out_iv - ssl->out_hdr);
1752 }
1753 
1754 static inline size_t mbedtls_ssl_hs_hdr_len(const mbedtls_ssl_context *ssl)
1755 {
1756 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1757     if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM) {
1758         return 12;
1759     }
1760 #else
1761     ((void) ssl);
1762 #endif
1763     return 4;
1764 }
1765 
1766 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1767 void mbedtls_ssl_send_flight_completed(mbedtls_ssl_context *ssl);
1768 void mbedtls_ssl_recv_flight_completed(mbedtls_ssl_context *ssl);
1769 MBEDTLS_CHECK_RETURN_CRITICAL
1770 int mbedtls_ssl_resend(mbedtls_ssl_context *ssl);
1771 MBEDTLS_CHECK_RETURN_CRITICAL
1772 int mbedtls_ssl_flight_transmit(mbedtls_ssl_context *ssl);
1773 #endif
1774 
1775 /* Visible for testing purposes only */
1776 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1777 MBEDTLS_CHECK_RETURN_CRITICAL
1778 int mbedtls_ssl_dtls_replay_check(mbedtls_ssl_context const *ssl);
1779 void mbedtls_ssl_dtls_replay_update(mbedtls_ssl_context *ssl);
1780 #endif
1781 
1782 MBEDTLS_CHECK_RETURN_CRITICAL
1783 int mbedtls_ssl_session_copy(mbedtls_ssl_session *dst,
1784                              const mbedtls_ssl_session *src);
1785 
1786 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
1787 /* The hash buffer must have at least MBEDTLS_MD_MAX_SIZE bytes of length. */
1788 MBEDTLS_CHECK_RETURN_CRITICAL
1789 int mbedtls_ssl_get_key_exchange_md_tls1_2(mbedtls_ssl_context *ssl,
1790                                            unsigned char *hash, size_t *hashlen,
1791                                            unsigned char *data, size_t data_len,
1792                                            mbedtls_md_type_t md_alg);
1793 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
1794 
1795 #ifdef __cplusplus
1796 }
1797 #endif
1798 
1799 void mbedtls_ssl_transform_init(mbedtls_ssl_transform *transform);
1800 MBEDTLS_CHECK_RETURN_CRITICAL
1801 int mbedtls_ssl_encrypt_buf(mbedtls_ssl_context *ssl,
1802                             mbedtls_ssl_transform *transform,
1803                             mbedtls_record *rec,
1804                             int (*f_rng)(void *, unsigned char *, size_t),
1805                             void *p_rng);
1806 MBEDTLS_CHECK_RETURN_CRITICAL
1807 int mbedtls_ssl_decrypt_buf(mbedtls_ssl_context const *ssl,
1808                             mbedtls_ssl_transform *transform,
1809                             mbedtls_record *rec);
1810 
1811 /* Length of the "epoch" field in the record header */
1812 static inline size_t mbedtls_ssl_ep_len(const mbedtls_ssl_context *ssl)
1813 {
1814 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1815     if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM) {
1816         return 2;
1817     }
1818 #else
1819     ((void) ssl);
1820 #endif
1821     return 0;
1822 }
1823 
1824 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1825 MBEDTLS_CHECK_RETURN_CRITICAL
1826 int mbedtls_ssl_resend_hello_request(mbedtls_ssl_context *ssl);
1827 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1828 
1829 void mbedtls_ssl_set_timer(mbedtls_ssl_context *ssl, uint32_t millisecs);
1830 MBEDTLS_CHECK_RETURN_CRITICAL
1831 int mbedtls_ssl_check_timer(mbedtls_ssl_context *ssl);
1832 
1833 void mbedtls_ssl_reset_in_pointers(mbedtls_ssl_context *ssl);
1834 void mbedtls_ssl_update_in_pointers(mbedtls_ssl_context *ssl);
1835 void mbedtls_ssl_reset_out_pointers(mbedtls_ssl_context *ssl);
1836 void mbedtls_ssl_update_out_pointers(mbedtls_ssl_context *ssl,
1837                                      mbedtls_ssl_transform *transform);
1838 
1839 MBEDTLS_CHECK_RETURN_CRITICAL
1840 int mbedtls_ssl_session_reset_int(mbedtls_ssl_context *ssl, int partial);
1841 void mbedtls_ssl_session_reset_msg_layer(mbedtls_ssl_context *ssl,
1842                                          int partial);
1843 
1844 /*
1845  * Send pending alert
1846  */
1847 MBEDTLS_CHECK_RETURN_CRITICAL
1848 int mbedtls_ssl_handle_pending_alert(mbedtls_ssl_context *ssl);
1849 
1850 /*
1851  * Set pending fatal alert flag.
1852  */
1853 void mbedtls_ssl_pend_fatal_alert(mbedtls_ssl_context *ssl,
1854                                   unsigned char alert_type,
1855                                   int alert_reason);
1856 
1857 /* Alias of mbedtls_ssl_pend_fatal_alert */
1858 #define MBEDTLS_SSL_PEND_FATAL_ALERT(type, user_return_value)         \
1859     mbedtls_ssl_pend_fatal_alert(ssl, type, user_return_value)
1860 
1861 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
1862 void mbedtls_ssl_dtls_replay_reset(mbedtls_ssl_context *ssl);
1863 #endif
1864 
1865 void mbedtls_ssl_handshake_wrapup_free_hs_transform(mbedtls_ssl_context *ssl);
1866 
1867 #if defined(MBEDTLS_SSL_RENEGOTIATION)
1868 MBEDTLS_CHECK_RETURN_CRITICAL
1869 int mbedtls_ssl_start_renegotiation(mbedtls_ssl_context *ssl);
1870 #endif /* MBEDTLS_SSL_RENEGOTIATION */
1871 
1872 #if defined(MBEDTLS_SSL_PROTO_DTLS)
1873 size_t mbedtls_ssl_get_current_mtu(const mbedtls_ssl_context *ssl);
1874 void mbedtls_ssl_buffering_free(mbedtls_ssl_context *ssl);
1875 void mbedtls_ssl_flight_free(mbedtls_ssl_flight_item *flight);
1876 #endif /* MBEDTLS_SSL_PROTO_DTLS */
1877 
1878 /**
1879  * ssl utils functions for checking configuration.
1880  */
1881 
1882 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1883 static inline int mbedtls_ssl_conf_is_tls13_only(const mbedtls_ssl_config *conf)
1884 {
1885     return conf->min_tls_version == MBEDTLS_SSL_VERSION_TLS1_3 &&
1886            conf->max_tls_version == MBEDTLS_SSL_VERSION_TLS1_3;
1887 }
1888 
1889 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
1890 
1891 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
1892 static inline int mbedtls_ssl_conf_is_tls12_only(const mbedtls_ssl_config *conf)
1893 {
1894     return conf->min_tls_version == MBEDTLS_SSL_VERSION_TLS1_2 &&
1895            conf->max_tls_version == MBEDTLS_SSL_VERSION_TLS1_2;
1896 }
1897 
1898 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
1899 
1900 static inline int mbedtls_ssl_conf_is_tls13_enabled(const mbedtls_ssl_config *conf)
1901 {
1902 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1903     return conf->min_tls_version <= MBEDTLS_SSL_VERSION_TLS1_3 &&
1904            conf->max_tls_version >= MBEDTLS_SSL_VERSION_TLS1_3;
1905 #else
1906     ((void) conf);
1907     return 0;
1908 #endif
1909 }
1910 
1911 static inline int mbedtls_ssl_conf_is_tls12_enabled(const mbedtls_ssl_config *conf)
1912 {
1913 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
1914     return conf->min_tls_version <= MBEDTLS_SSL_VERSION_TLS1_2 &&
1915            conf->max_tls_version >= MBEDTLS_SSL_VERSION_TLS1_2;
1916 #else
1917     ((void) conf);
1918     return 0;
1919 #endif
1920 }
1921 
1922 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && defined(MBEDTLS_SSL_PROTO_TLS1_3)
1923 static inline int mbedtls_ssl_conf_is_hybrid_tls12_tls13(const mbedtls_ssl_config *conf)
1924 {
1925     return conf->min_tls_version == MBEDTLS_SSL_VERSION_TLS1_2 &&
1926            conf->max_tls_version == MBEDTLS_SSL_VERSION_TLS1_3;
1927 }
1928 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 && MBEDTLS_SSL_PROTO_TLS1_3 */
1929 
1930 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
1931 
1932 /** \brief Initialize the PSA crypto subsystem if necessary.
1933  *
1934  * Call this function before doing any cryptography in a TLS 1.3 handshake.
1935  *
1936  * This is necessary in Mbed TLS 3.x for backward compatibility.
1937  * Up to Mbed TLS 3.5, in the default configuration, you could perform
1938  * a TLS connection with default parameters without having called
1939  * psa_crypto_init(), since the TLS layer only supported TLS 1.2 and
1940  * did not use PSA crypto. (TLS 1.2 only uses PSA crypto if
1941  * MBEDTLS_USE_PSA_CRYPTO is enabled, which is not the case in the default
1942  * configuration.) Starting with Mbed TLS 3.6.0, TLS 1.3 is enabled
1943  * by default, and the TLS 1.3 layer uses PSA crypto. This means that
1944  * applications that are not otherwise using PSA crypto and that worked
1945  * with Mbed TLS 3.5 started failing in TLS 3.6.0 if they connected to
1946  * a peer that supports TLS 1.3. See
1947  * https://github.com/Mbed-TLS/mbedtls/issues/9072
1948  */
1949 int mbedtls_ssl_tls13_crypto_init(mbedtls_ssl_context *ssl);
1950 
1951 extern const uint8_t mbedtls_ssl_tls13_hello_retry_request_magic[
1952     MBEDTLS_SERVER_HELLO_RANDOM_LEN];
1953 MBEDTLS_CHECK_RETURN_CRITICAL
1954 int mbedtls_ssl_tls13_process_finished_message(mbedtls_ssl_context *ssl);
1955 MBEDTLS_CHECK_RETURN_CRITICAL
1956 int mbedtls_ssl_tls13_write_finished_message(mbedtls_ssl_context *ssl);
1957 void mbedtls_ssl_tls13_handshake_wrapup(mbedtls_ssl_context *ssl);
1958 
1959 /**
1960  * \brief Given an SSL context and its associated configuration, write the TLS
1961  *        1.3 specific extensions of the ClientHello message.
1962  *
1963  * \param[in]   ssl     SSL context
1964  * \param[in]   buf     Base address of the buffer where to write the extensions
1965  * \param[in]   end     End address of the buffer where to write the extensions
1966  * \param[out]  out_len Length of the data written into the buffer \p buf
1967  */
1968 MBEDTLS_CHECK_RETURN_CRITICAL
1969 int mbedtls_ssl_tls13_write_client_hello_exts(mbedtls_ssl_context *ssl,
1970                                               unsigned char *buf,
1971                                               unsigned char *end,
1972                                               size_t *out_len);
1973 
1974 /**
1975  * \brief           TLS 1.3 client side state machine entry
1976  *
1977  * \param ssl       SSL context
1978  */
1979 MBEDTLS_CHECK_RETURN_CRITICAL
1980 int mbedtls_ssl_tls13_handshake_client_step(mbedtls_ssl_context *ssl);
1981 
1982 /**
1983  * \brief           TLS 1.3 server side state machine entry
1984  *
1985  * \param ssl       SSL context
1986  */
1987 MBEDTLS_CHECK_RETURN_CRITICAL
1988 int mbedtls_ssl_tls13_handshake_server_step(mbedtls_ssl_context *ssl);
1989 
1990 
1991 /*
1992  * Helper functions around key exchange modes.
1993  */
1994 static inline int mbedtls_ssl_conf_tls13_is_kex_mode_enabled(mbedtls_ssl_context *ssl,
1995                                                              int kex_mode_mask)
1996 {
1997     return (ssl->conf->tls13_kex_modes & kex_mode_mask) != 0;
1998 }
1999 
2000 static inline int mbedtls_ssl_conf_tls13_is_psk_enabled(mbedtls_ssl_context *ssl)
2001 {
2002     return mbedtls_ssl_conf_tls13_is_kex_mode_enabled(ssl,
2003                                                       MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK);
2004 }
2005 
2006 static inline int mbedtls_ssl_conf_tls13_is_psk_ephemeral_enabled(mbedtls_ssl_context *ssl)
2007 {
2008     return mbedtls_ssl_conf_tls13_is_kex_mode_enabled(ssl,
2009                                                       MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL);
2010 }
2011 
2012 static inline int mbedtls_ssl_conf_tls13_is_ephemeral_enabled(mbedtls_ssl_context *ssl)
2013 {
2014     return mbedtls_ssl_conf_tls13_is_kex_mode_enabled(ssl,
2015                                                       MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL);
2016 }
2017 
2018 static inline int mbedtls_ssl_conf_tls13_is_some_ephemeral_enabled(mbedtls_ssl_context *ssl)
2019 {
2020     return mbedtls_ssl_conf_tls13_is_kex_mode_enabled(ssl,
2021                                                       MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL);
2022 }
2023 
2024 static inline int mbedtls_ssl_conf_tls13_is_some_psk_enabled(mbedtls_ssl_context *ssl)
2025 {
2026     return mbedtls_ssl_conf_tls13_is_kex_mode_enabled(ssl,
2027                                                       MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL);
2028 }
2029 
2030 #if defined(MBEDTLS_SSL_SRV_C) && \
2031     defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
2032 /**
2033  * Given a list of key exchange modes, check if at least one of them is
2034  * supported by peer.
2035  *
2036  * \param[in] ssl  SSL context
2037  * \param kex_modes_mask  Mask of the key exchange modes to check
2038  *
2039  * \return Non-zero if at least one of the key exchange modes is supported by
2040  *         the peer, otherwise \c 0.
2041  */
2042 static inline int mbedtls_ssl_tls13_is_kex_mode_supported(mbedtls_ssl_context *ssl,
2043                                                           int kex_modes_mask)
2044 {
2045     return (ssl->handshake->tls13_kex_modes & kex_modes_mask) != 0;
2046 }
2047 
2048 static inline int mbedtls_ssl_tls13_is_psk_supported(mbedtls_ssl_context *ssl)
2049 {
2050     return mbedtls_ssl_tls13_is_kex_mode_supported(ssl,
2051                                                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK);
2052 }
2053 
2054 static inline int mbedtls_ssl_tls13_is_psk_ephemeral_supported(
2055     mbedtls_ssl_context *ssl)
2056 {
2057     return mbedtls_ssl_tls13_is_kex_mode_supported(ssl,
2058                                                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL);
2059 }
2060 
2061 static inline int mbedtls_ssl_tls13_is_ephemeral_supported(mbedtls_ssl_context *ssl)
2062 {
2063     return mbedtls_ssl_tls13_is_kex_mode_supported(ssl,
2064                                                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL);
2065 }
2066 
2067 static inline int mbedtls_ssl_tls13_is_some_ephemeral_supported(mbedtls_ssl_context *ssl)
2068 {
2069     return mbedtls_ssl_tls13_is_kex_mode_supported(ssl,
2070                                                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL);
2071 }
2072 
2073 static inline int mbedtls_ssl_tls13_is_some_psk_supported(mbedtls_ssl_context *ssl)
2074 {
2075     return mbedtls_ssl_tls13_is_kex_mode_supported(ssl,
2076                                                    MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL);
2077 }
2078 #endif /* MBEDTLS_SSL_SRV_C &&
2079           MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED */
2080 
2081 /*
2082  * Helper functions for extensions checking.
2083  */
2084 
2085 MBEDTLS_CHECK_RETURN_CRITICAL
2086 int mbedtls_ssl_tls13_check_received_extension(
2087     mbedtls_ssl_context *ssl,
2088     int hs_msg_type,
2089     unsigned int received_extension_type,
2090     uint32_t hs_msg_allowed_extensions_mask);
2091 
2092 static inline void mbedtls_ssl_tls13_set_hs_sent_ext_mask(
2093     mbedtls_ssl_context *ssl, unsigned int extension_type)
2094 {
2095     ssl->handshake->sent_extensions |=
2096         mbedtls_ssl_get_extension_mask(extension_type);
2097 }
2098 
2099 /*
2100  * Helper functions to check the selected key exchange mode.
2101  */
2102 static inline int mbedtls_ssl_tls13_key_exchange_mode_check(
2103     mbedtls_ssl_context *ssl, int kex_mask)
2104 {
2105     return (ssl->handshake->key_exchange_mode & kex_mask) != 0;
2106 }
2107 
2108 static inline int mbedtls_ssl_tls13_key_exchange_mode_with_psk(
2109     mbedtls_ssl_context *ssl)
2110 {
2111     return mbedtls_ssl_tls13_key_exchange_mode_check(ssl,
2112                                                      MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL);
2113 }
2114 
2115 static inline int mbedtls_ssl_tls13_key_exchange_mode_with_ephemeral(
2116     mbedtls_ssl_context *ssl)
2117 {
2118     return mbedtls_ssl_tls13_key_exchange_mode_check(ssl,
2119                                                      MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL);
2120 }
2121 
2122 /*
2123  * Fetch TLS 1.3 handshake message header
2124  */
2125 MBEDTLS_CHECK_RETURN_CRITICAL
2126 int mbedtls_ssl_tls13_fetch_handshake_msg(mbedtls_ssl_context *ssl,
2127                                           unsigned hs_type,
2128                                           unsigned char **buf,
2129                                           size_t *buf_len);
2130 
2131 /**
2132  * \brief Detect if a list of extensions contains a supported_versions
2133  *        extension or not.
2134  *
2135  * \param[in] ssl  SSL context
2136  * \param[in] buf  Address of the first byte of the extensions vector.
2137  * \param[in] end  End of the buffer containing the list of extensions.
2138  * \param[out] supported_versions_data  If the extension is present, address of
2139  *                                      its first byte of data, NULL otherwise.
2140  * \param[out] supported_versions_data_end  If the extension is present, address
2141  *                                          of the first byte immediately
2142  *                                          following the extension data, NULL
2143  *                                          otherwise.
2144  * \return 0  if the list of extensions does not contain a supported_versions
2145  *            extension.
2146  * \return 1  if the list of extensions contains a supported_versions
2147  *            extension.
2148  * \return    A negative value if an error occurred while parsing the
2149  *            extensions.
2150  */
2151 MBEDTLS_CHECK_RETURN_CRITICAL
2152 int mbedtls_ssl_tls13_is_supported_versions_ext_present_in_exts(
2153     mbedtls_ssl_context *ssl,
2154     const unsigned char *buf, const unsigned char *end,
2155     const unsigned char **supported_versions_data,
2156     const unsigned char **supported_versions_data_end);
2157 
2158 /*
2159  * Handler of TLS 1.3 server certificate message
2160  */
2161 MBEDTLS_CHECK_RETURN_CRITICAL
2162 int mbedtls_ssl_tls13_process_certificate(mbedtls_ssl_context *ssl);
2163 
2164 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED)
2165 /*
2166  * Handler of TLS 1.3 write Certificate message
2167  */
2168 MBEDTLS_CHECK_RETURN_CRITICAL
2169 int mbedtls_ssl_tls13_write_certificate(mbedtls_ssl_context *ssl);
2170 
2171 /*
2172  * Handler of TLS 1.3 write Certificate Verify message
2173  */
2174 MBEDTLS_CHECK_RETURN_CRITICAL
2175 int mbedtls_ssl_tls13_write_certificate_verify(mbedtls_ssl_context *ssl);
2176 
2177 #endif /* MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED */
2178 
2179 /*
2180  * Generic handler of Certificate Verify
2181  */
2182 MBEDTLS_CHECK_RETURN_CRITICAL
2183 int mbedtls_ssl_tls13_process_certificate_verify(mbedtls_ssl_context *ssl);
2184 
2185 /*
2186  * Write of dummy-CCS's for middlebox compatibility
2187  */
2188 MBEDTLS_CHECK_RETURN_CRITICAL
2189 int mbedtls_ssl_tls13_write_change_cipher_spec(mbedtls_ssl_context *ssl);
2190 
2191 MBEDTLS_CHECK_RETURN_CRITICAL
2192 int mbedtls_ssl_reset_transcript_for_hrr(mbedtls_ssl_context *ssl);
2193 
2194 #if defined(PSA_WANT_ALG_ECDH) || defined(PSA_WANT_ALG_FFDH)
2195 MBEDTLS_CHECK_RETURN_CRITICAL
2196 int mbedtls_ssl_tls13_generate_and_write_xxdh_key_exchange(
2197     mbedtls_ssl_context *ssl,
2198     uint16_t named_group,
2199     unsigned char *buf,
2200     unsigned char *end,
2201     size_t *out_len);
2202 #endif /* PSA_WANT_ALG_ECDH || PSA_WANT_ALG_FFDH */
2203 
2204 #if defined(MBEDTLS_SSL_EARLY_DATA)
2205 int mbedtls_ssl_tls13_write_early_data_ext(mbedtls_ssl_context *ssl,
2206                                            int in_new_session_ticket,
2207                                            unsigned char *buf,
2208                                            const unsigned char *end,
2209                                            size_t *out_len);
2210 
2211 int mbedtls_ssl_tls13_check_early_data_len(mbedtls_ssl_context *ssl,
2212                                            size_t early_data_len);
2213 
2214 typedef enum {
2215 /*
2216  * The client has not sent the first ClientHello yet, the negotiation of early
2217  * data has not started yet.
2218  */
2219     MBEDTLS_SSL_EARLY_DATA_STATE_IDLE,
2220 
2221 /*
2222  * In its ClientHello, the client has not included an early data indication
2223  * extension.
2224  */
2225     MBEDTLS_SSL_EARLY_DATA_STATE_NO_IND_SENT,
2226 
2227 /*
2228  * The client has sent an early data indication extension in its first
2229  * ClientHello, it has not received the response (ServerHello or
2230  * HelloRetryRequest) from the server yet. The transform to protect early data
2231  * is not set either as for middlebox compatibility a dummy CCS may have to be
2232  * sent in clear. Early data cannot be sent to the server yet.
2233  */
2234     MBEDTLS_SSL_EARLY_DATA_STATE_IND_SENT,
2235 
2236 /*
2237  * The client has sent an early data indication extension in its first
2238  * ClientHello, it has not received the response (ServerHello or
2239  * HelloRetryRequest) from the server yet. The transform to protect early data
2240  * has been set and early data can be written now.
2241  */
2242     MBEDTLS_SSL_EARLY_DATA_STATE_CAN_WRITE,
2243 
2244 /*
2245  * The client has indicated the use of early data and the server has accepted
2246  * it.
2247  */
2248     MBEDTLS_SSL_EARLY_DATA_STATE_ACCEPTED,
2249 
2250 /*
2251  * The client has indicated the use of early data but the server has rejected
2252  * it.
2253  */
2254     MBEDTLS_SSL_EARLY_DATA_STATE_REJECTED,
2255 
2256 /*
2257  * The client has sent an early data indication extension in its first
2258  * ClientHello, the server has accepted them and the client has received the
2259  * server Finished message. It cannot send early data to the server anymore.
2260  */
2261     MBEDTLS_SSL_EARLY_DATA_STATE_SERVER_FINISHED_RECEIVED,
2262 
2263 } mbedtls_ssl_early_data_state;
2264 #endif /* MBEDTLS_SSL_EARLY_DATA */
2265 
2266 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
2267 
2268 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
2269 /*
2270  * Write Signature Algorithm extension
2271  */
2272 MBEDTLS_CHECK_RETURN_CRITICAL
2273 int mbedtls_ssl_write_sig_alg_ext(mbedtls_ssl_context *ssl, unsigned char *buf,
2274                                   const unsigned char *end, size_t *out_len);
2275 /*
2276  * Parse TLS Signature Algorithm extension
2277  */
2278 MBEDTLS_CHECK_RETURN_CRITICAL
2279 int mbedtls_ssl_parse_sig_alg_ext(mbedtls_ssl_context *ssl,
2280                                   const unsigned char *buf,
2281                                   const unsigned char *end);
2282 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
2283 
2284 /* Get handshake transcript */
2285 MBEDTLS_CHECK_RETURN_CRITICAL
2286 int mbedtls_ssl_get_handshake_transcript(mbedtls_ssl_context *ssl,
2287                                          const mbedtls_md_type_t md,
2288                                          unsigned char *dst,
2289                                          size_t dst_len,
2290                                          size_t *olen);
2291 
2292 /*
2293  * Return supported groups.
2294  *
2295  * In future, invocations can be changed to ssl->conf->group_list
2296  * when mbedtls_ssl_conf_curves() is deleted.
2297  *
2298  * ssl->handshake->group_list is either a translation of curve_list to IANA TLS group
2299  * identifiers when mbedtls_ssl_conf_curves() has been used, or a pointer to
2300  * ssl->conf->group_list when mbedtls_ssl_conf_groups() has been more recently invoked.
2301  *
2302  */
2303 static inline const void *mbedtls_ssl_get_groups(const mbedtls_ssl_context *ssl)
2304 {
2305     #if defined(MBEDTLS_DEPRECATED_REMOVED) || !defined(MBEDTLS_ECP_C)
2306     return ssl->conf->group_list;
2307     #else
2308     if ((ssl->handshake != NULL) && (ssl->handshake->group_list != NULL)) {
2309         return ssl->handshake->group_list;
2310     } else {
2311         return ssl->conf->group_list;
2312     }
2313     #endif
2314 }
2315 
2316 /*
2317  * Helper functions for NamedGroup.
2318  */
2319 static inline int mbedtls_ssl_tls12_named_group_is_ecdhe(uint16_t named_group)
2320 {
2321     /*
2322      * RFC 8422 section 5.1.1
2323      */
2324     return named_group == MBEDTLS_SSL_IANA_TLS_GROUP_X25519    ||
2325            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_BP256R1   ||
2326            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_BP384R1   ||
2327            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_BP512R1   ||
2328            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_X448      ||
2329            /* Below deprecated curves should be removed with notice to users */
2330            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP192K1 ||
2331            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP192R1 ||
2332            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP224K1 ||
2333            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP224R1 ||
2334            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP256K1 ||
2335            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP256R1 ||
2336            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP384R1 ||
2337            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP521R1;
2338 }
2339 
2340 static inline int mbedtls_ssl_tls13_named_group_is_ecdhe(uint16_t named_group)
2341 {
2342     return named_group == MBEDTLS_SSL_IANA_TLS_GROUP_X25519    ||
2343            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP256R1 ||
2344            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP384R1 ||
2345            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_SECP521R1 ||
2346            named_group == MBEDTLS_SSL_IANA_TLS_GROUP_X448;
2347 }
2348 
2349 static inline int mbedtls_ssl_tls13_named_group_is_ffdh(uint16_t named_group)
2350 {
2351     return named_group >= MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE2048 &&
2352            named_group <= MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE8192;
2353 }
2354 
2355 static inline int mbedtls_ssl_named_group_is_offered(
2356     const mbedtls_ssl_context *ssl, uint16_t named_group)
2357 {
2358     const uint16_t *group_list = mbedtls_ssl_get_groups(ssl);
2359 
2360     if (group_list == NULL) {
2361         return 0;
2362     }
2363 
2364     for (; *group_list != 0; group_list++) {
2365         if (*group_list == named_group) {
2366             return 1;
2367         }
2368     }
2369 
2370     return 0;
2371 }
2372 
2373 static inline int mbedtls_ssl_named_group_is_supported(uint16_t named_group)
2374 {
2375 #if defined(PSA_WANT_ALG_ECDH)
2376     if (mbedtls_ssl_tls13_named_group_is_ecdhe(named_group)) {
2377         if (mbedtls_ssl_get_ecp_group_id_from_tls_id(named_group) !=
2378             MBEDTLS_ECP_DP_NONE) {
2379             return 1;
2380         }
2381     }
2382 #endif
2383 #if defined(PSA_WANT_ALG_FFDH)
2384     if (mbedtls_ssl_tls13_named_group_is_ffdh(named_group)) {
2385         return 1;
2386     }
2387 #endif
2388 #if !defined(PSA_WANT_ALG_ECDH) && !defined(PSA_WANT_ALG_FFDH)
2389     (void) named_group;
2390 #endif
2391     return 0;
2392 }
2393 
2394 /*
2395  * Return supported signature algorithms.
2396  *
2397  * In future, invocations can be changed to ssl->conf->sig_algs when
2398  * mbedtls_ssl_conf_sig_hashes() is deleted.
2399  *
2400  * ssl->handshake->sig_algs is either a translation of sig_hashes to IANA TLS
2401  * signature algorithm identifiers when mbedtls_ssl_conf_sig_hashes() has been
2402  * used, or a pointer to ssl->conf->sig_algs when mbedtls_ssl_conf_sig_algs() has
2403  * been more recently invoked.
2404  *
2405  */
2406 static inline const void *mbedtls_ssl_get_sig_algs(
2407     const mbedtls_ssl_context *ssl)
2408 {
2409 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
2410 
2411 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
2412     if (ssl->handshake != NULL &&
2413         ssl->handshake->sig_algs_heap_allocated == 1 &&
2414         ssl->handshake->sig_algs != NULL) {
2415         return ssl->handshake->sig_algs;
2416     }
2417 #endif
2418     return ssl->conf->sig_algs;
2419 
2420 #else /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
2421 
2422     ((void) ssl);
2423     return NULL;
2424 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
2425 }
2426 
2427 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED)
2428 static inline int mbedtls_ssl_sig_alg_is_received(const mbedtls_ssl_context *ssl,
2429                                                   uint16_t own_sig_alg)
2430 {
2431     const uint16_t *sig_alg = ssl->handshake->received_sig_algs;
2432     if (sig_alg == NULL) {
2433         return 0;
2434     }
2435 
2436     for (; *sig_alg != MBEDTLS_TLS_SIG_NONE; sig_alg++) {
2437         if (*sig_alg == own_sig_alg) {
2438             return 1;
2439         }
2440     }
2441     return 0;
2442 }
2443 
2444 static inline int mbedtls_ssl_tls13_sig_alg_for_cert_verify_is_supported(
2445     const uint16_t sig_alg)
2446 {
2447     switch (sig_alg) {
2448 #if defined(MBEDTLS_PK_CAN_ECDSA_SOME)
2449 #if defined(PSA_WANT_ALG_SHA_256) && defined(PSA_WANT_ECC_SECP_R1_256)
2450         case MBEDTLS_TLS1_3_SIG_ECDSA_SECP256R1_SHA256:
2451             break;
2452 #endif /* PSA_WANT_ALG_SHA_256 && MBEDTLS_ECP_DP_SECP256R1_ENABLED */
2453 #if defined(PSA_WANT_ALG_SHA_384) && defined(PSA_WANT_ECC_SECP_R1_384)
2454         case MBEDTLS_TLS1_3_SIG_ECDSA_SECP384R1_SHA384:
2455             break;
2456 #endif /* PSA_WANT_ALG_SHA_384 && MBEDTLS_ECP_DP_SECP384R1_ENABLED */
2457 #if defined(PSA_WANT_ALG_SHA_512) && defined(PSA_WANT_ECC_SECP_R1_521)
2458         case MBEDTLS_TLS1_3_SIG_ECDSA_SECP521R1_SHA512:
2459             break;
2460 #endif /* PSA_WANT_ALG_SHA_512 && MBEDTLS_ECP_DP_SECP521R1_ENABLED */
2461 #endif /* MBEDTLS_PK_CAN_ECDSA_SOME */
2462 
2463 #if defined(MBEDTLS_PKCS1_V21)
2464 #if defined(PSA_WANT_ALG_SHA_256)
2465         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA256:
2466             break;
2467 #endif /* PSA_WANT_ALG_SHA_256  */
2468 #if defined(PSA_WANT_ALG_SHA_384)
2469         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA384:
2470             break;
2471 #endif /* PSA_WANT_ALG_SHA_384 */
2472 #if defined(PSA_WANT_ALG_SHA_512)
2473         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA512:
2474             break;
2475 #endif /* PSA_WANT_ALG_SHA_512 */
2476 #endif /* MBEDTLS_PKCS1_V21 */
2477         default:
2478             return 0;
2479     }
2480     return 1;
2481 
2482 }
2483 
2484 static inline int mbedtls_ssl_tls13_sig_alg_is_supported(
2485     const uint16_t sig_alg)
2486 {
2487     switch (sig_alg) {
2488 #if defined(MBEDTLS_PKCS1_V15)
2489 #if defined(MBEDTLS_MD_CAN_SHA256)
2490         case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA256:
2491             break;
2492 #endif /* MBEDTLS_MD_CAN_SHA256 */
2493 #if defined(MBEDTLS_MD_CAN_SHA384)
2494         case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA384:
2495             break;
2496 #endif /* MBEDTLS_MD_CAN_SHA384 */
2497 #if defined(MBEDTLS_MD_CAN_SHA512)
2498         case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA512:
2499             break;
2500 #endif /* MBEDTLS_MD_CAN_SHA512 */
2501 #endif /* MBEDTLS_PKCS1_V15 */
2502         default:
2503             return mbedtls_ssl_tls13_sig_alg_for_cert_verify_is_supported(
2504                 sig_alg);
2505     }
2506     return 1;
2507 }
2508 
2509 MBEDTLS_CHECK_RETURN_CRITICAL
2510 int mbedtls_ssl_tls13_check_sig_alg_cert_key_match(uint16_t sig_alg,
2511                                                    mbedtls_pk_context *key);
2512 #endif /* MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED */
2513 
2514 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
2515 static inline int mbedtls_ssl_sig_alg_is_offered(const mbedtls_ssl_context *ssl,
2516                                                  uint16_t proposed_sig_alg)
2517 {
2518     const uint16_t *sig_alg = mbedtls_ssl_get_sig_algs(ssl);
2519     if (sig_alg == NULL) {
2520         return 0;
2521     }
2522 
2523     for (; *sig_alg != MBEDTLS_TLS_SIG_NONE; sig_alg++) {
2524         if (*sig_alg == proposed_sig_alg) {
2525             return 1;
2526         }
2527     }
2528     return 0;
2529 }
2530 
2531 static inline int mbedtls_ssl_get_pk_type_and_md_alg_from_sig_alg(
2532     uint16_t sig_alg, mbedtls_pk_type_t *pk_type, mbedtls_md_type_t *md_alg)
2533 {
2534     *pk_type = mbedtls_ssl_pk_alg_from_sig(sig_alg & 0xff);
2535     *md_alg = mbedtls_ssl_md_alg_from_hash((sig_alg >> 8) & 0xff);
2536 
2537     if (*pk_type != MBEDTLS_PK_NONE && *md_alg != MBEDTLS_MD_NONE) {
2538         return 0;
2539     }
2540 
2541     switch (sig_alg) {
2542 #if defined(MBEDTLS_PKCS1_V21)
2543 #if defined(MBEDTLS_MD_CAN_SHA256)
2544         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA256:
2545             *md_alg = MBEDTLS_MD_SHA256;
2546             *pk_type = MBEDTLS_PK_RSASSA_PSS;
2547             break;
2548 #endif /* MBEDTLS_MD_CAN_SHA256  */
2549 #if defined(MBEDTLS_MD_CAN_SHA384)
2550         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA384:
2551             *md_alg = MBEDTLS_MD_SHA384;
2552             *pk_type = MBEDTLS_PK_RSASSA_PSS;
2553             break;
2554 #endif /* MBEDTLS_MD_CAN_SHA384 */
2555 #if defined(MBEDTLS_MD_CAN_SHA512)
2556         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA512:
2557             *md_alg = MBEDTLS_MD_SHA512;
2558             *pk_type = MBEDTLS_PK_RSASSA_PSS;
2559             break;
2560 #endif /* MBEDTLS_MD_CAN_SHA512 */
2561 #endif /* MBEDTLS_PKCS1_V21 */
2562         default:
2563             return MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
2564     }
2565     return 0;
2566 }
2567 
2568 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
2569 static inline int mbedtls_ssl_tls12_sig_alg_is_supported(
2570     const uint16_t sig_alg)
2571 {
2572     /* High byte is hash */
2573     unsigned char hash = MBEDTLS_BYTE_1(sig_alg);
2574     unsigned char sig = MBEDTLS_BYTE_0(sig_alg);
2575 
2576     switch (hash) {
2577 #if defined(MBEDTLS_MD_CAN_MD5)
2578         case MBEDTLS_SSL_HASH_MD5:
2579             break;
2580 #endif
2581 
2582 #if defined(MBEDTLS_MD_CAN_SHA1)
2583         case MBEDTLS_SSL_HASH_SHA1:
2584             break;
2585 #endif
2586 
2587 #if defined(MBEDTLS_MD_CAN_SHA224)
2588         case MBEDTLS_SSL_HASH_SHA224:
2589             break;
2590 #endif
2591 
2592 #if defined(MBEDTLS_MD_CAN_SHA256)
2593         case MBEDTLS_SSL_HASH_SHA256:
2594             break;
2595 #endif
2596 
2597 #if defined(MBEDTLS_MD_CAN_SHA384)
2598         case MBEDTLS_SSL_HASH_SHA384:
2599             break;
2600 #endif
2601 
2602 #if defined(MBEDTLS_MD_CAN_SHA512)
2603         case MBEDTLS_SSL_HASH_SHA512:
2604             break;
2605 #endif
2606 
2607         default:
2608             return 0;
2609     }
2610 
2611     switch (sig) {
2612 #if defined(MBEDTLS_RSA_C)
2613         case MBEDTLS_SSL_SIG_RSA:
2614             break;
2615 #endif
2616 
2617 #if defined(MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ALLOWED_ENABLED)
2618         case MBEDTLS_SSL_SIG_ECDSA:
2619             break;
2620 #endif
2621 
2622         default:
2623             return 0;
2624     }
2625 
2626     return 1;
2627 }
2628 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
2629 
2630 static inline int mbedtls_ssl_sig_alg_is_supported(
2631     const mbedtls_ssl_context *ssl,
2632     const uint16_t sig_alg)
2633 {
2634 
2635 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
2636     if (ssl->tls_version == MBEDTLS_SSL_VERSION_TLS1_2) {
2637         return mbedtls_ssl_tls12_sig_alg_is_supported(sig_alg);
2638     }
2639 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
2640 
2641 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED)
2642     if (ssl->tls_version == MBEDTLS_SSL_VERSION_TLS1_3) {
2643         return mbedtls_ssl_tls13_sig_alg_is_supported(sig_alg);
2644     }
2645 #endif
2646     ((void) ssl);
2647     ((void) sig_alg);
2648     return 0;
2649 }
2650 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
2651 
2652 #if defined(MBEDTLS_USE_PSA_CRYPTO) || defined(MBEDTLS_SSL_PROTO_TLS1_3)
2653 /* Corresponding PSA algorithm for MBEDTLS_CIPHER_NULL.
2654  * Same value is used for PSA_ALG_CATEGORY_CIPHER, hence it is
2655  * guaranteed to not be a valid PSA algorithm identifier.
2656  */
2657 #define MBEDTLS_SSL_NULL_CIPHER 0x04000000
2658 
2659 /**
2660  * \brief       Translate mbedtls cipher type/taglen pair to psa:
2661  *              algorithm, key type and key size.
2662  *
2663  * \param  mbedtls_cipher_type [in] given mbedtls cipher type
2664  * \param  taglen              [in] given tag length
2665  *                                  0 - default tag length
2666  * \param  alg                 [out] corresponding PSA alg
2667  *                                   There is no corresponding PSA
2668  *                                   alg for MBEDTLS_CIPHER_NULL, so
2669  *                                   in this case MBEDTLS_SSL_NULL_CIPHER
2670  *                                   is returned via this parameter
2671  * \param  key_type            [out] corresponding PSA key type
2672  * \param  key_size            [out] corresponding PSA key size
2673  *
2674  * \return                     PSA_SUCCESS on success or PSA_ERROR_NOT_SUPPORTED if
2675  *                             conversion is not supported.
2676  */
2677 psa_status_t mbedtls_ssl_cipher_to_psa(mbedtls_cipher_type_t mbedtls_cipher_type,
2678                                        size_t taglen,
2679                                        psa_algorithm_t *alg,
2680                                        psa_key_type_t *key_type,
2681                                        size_t *key_size);
2682 
2683 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
2684 /**
2685  * \brief       Convert given PSA status to mbedtls error code.
2686  *
2687  * \param  status      [in] given PSA status
2688  *
2689  * \return             corresponding mbedtls error code
2690  */
2691 static inline MBEDTLS_DEPRECATED int psa_ssl_status_to_mbedtls(psa_status_t status)
2692 {
2693     switch (status) {
2694         case PSA_SUCCESS:
2695             return 0;
2696         case PSA_ERROR_INSUFFICIENT_MEMORY:
2697             return MBEDTLS_ERR_SSL_ALLOC_FAILED;
2698         case PSA_ERROR_NOT_SUPPORTED:
2699             return MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
2700         case PSA_ERROR_INVALID_SIGNATURE:
2701             return MBEDTLS_ERR_SSL_INVALID_MAC;
2702         case PSA_ERROR_INVALID_ARGUMENT:
2703             return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
2704         case PSA_ERROR_BAD_STATE:
2705             return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
2706         case PSA_ERROR_BUFFER_TOO_SMALL:
2707             return MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL;
2708         default:
2709             return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
2710     }
2711 }
2712 #endif /* !MBEDTLS_DEPRECATED_REMOVED */
2713 #endif /* MBEDTLS_USE_PSA_CRYPTO || MBEDTLS_SSL_PROTO_TLS1_3 */
2714 
2715 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) && \
2716     defined(MBEDTLS_USE_PSA_CRYPTO)
2717 
2718 typedef enum {
2719     MBEDTLS_ECJPAKE_ROUND_ONE,
2720     MBEDTLS_ECJPAKE_ROUND_TWO
2721 } mbedtls_ecjpake_rounds_t;
2722 
2723 /**
2724  * \brief       Parse the provided input buffer for getting the first round
2725  *              of key exchange. This code is common between server and client
2726  *
2727  * \param  pake_ctx [in] the PAKE's operation/context structure
2728  * \param  buf      [in] input buffer to parse
2729  * \param  len      [in] length of the input buffer
2730  * \param  round    [in] either MBEDTLS_ECJPAKE_ROUND_ONE or
2731  *                       MBEDTLS_ECJPAKE_ROUND_TWO
2732  *
2733  * \return               0 on success or a negative error code in case of failure
2734  */
2735 int mbedtls_psa_ecjpake_read_round(
2736     psa_pake_operation_t *pake_ctx,
2737     const unsigned char *buf,
2738     size_t len, mbedtls_ecjpake_rounds_t round);
2739 
2740 /**
2741  * \brief       Write the first round of key exchange into the provided output
2742  *              buffer. This code is common between server and client
2743  *
2744  * \param  pake_ctx [in] the PAKE's operation/context structure
2745  * \param  buf      [out] the output buffer in which data will be written to
2746  * \param  len      [in] length of the output buffer
2747  * \param  olen     [out] the length of the data really written on the buffer
2748  * \param  round    [in] either MBEDTLS_ECJPAKE_ROUND_ONE or
2749  *                       MBEDTLS_ECJPAKE_ROUND_TWO
2750  *
2751  * \return               0 on success or a negative error code in case of failure
2752  */
2753 int mbedtls_psa_ecjpake_write_round(
2754     psa_pake_operation_t *pake_ctx,
2755     unsigned char *buf,
2756     size_t len, size_t *olen,
2757     mbedtls_ecjpake_rounds_t round);
2758 
2759 #endif //MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED && MBEDTLS_USE_PSA_CRYPTO
2760 
2761 /**
2762  * \brief       TLS record protection modes
2763  */
2764 typedef enum {
2765     MBEDTLS_SSL_MODE_STREAM = 0,
2766     MBEDTLS_SSL_MODE_CBC,
2767     MBEDTLS_SSL_MODE_CBC_ETM,
2768     MBEDTLS_SSL_MODE_AEAD
2769 } mbedtls_ssl_mode_t;
2770 
2771 mbedtls_ssl_mode_t mbedtls_ssl_get_mode_from_transform(
2772     const mbedtls_ssl_transform *transform);
2773 
2774 #if defined(MBEDTLS_SSL_SOME_SUITES_USE_CBC_ETM)
2775 mbedtls_ssl_mode_t mbedtls_ssl_get_mode_from_ciphersuite(
2776     int encrypt_then_mac,
2777     const mbedtls_ssl_ciphersuite_t *suite);
2778 #else
2779 mbedtls_ssl_mode_t mbedtls_ssl_get_mode_from_ciphersuite(
2780     const mbedtls_ssl_ciphersuite_t *suite);
2781 #endif /* MBEDTLS_SSL_SOME_SUITES_USE_CBC_ETM */
2782 
2783 #if defined(PSA_WANT_ALG_ECDH) || defined(PSA_WANT_ALG_FFDH)
2784 
2785 MBEDTLS_CHECK_RETURN_CRITICAL
2786 int mbedtls_ssl_tls13_read_public_xxdhe_share(mbedtls_ssl_context *ssl,
2787                                               const unsigned char *buf,
2788                                               size_t buf_len);
2789 
2790 #endif /* PSA_WANT_ALG_ECDH || PSA_WANT_ALG_FFDH */
2791 
2792 static inline int mbedtls_ssl_tls13_cipher_suite_is_offered(
2793     mbedtls_ssl_context *ssl, int cipher_suite)
2794 {
2795     const int *ciphersuite_list = ssl->conf->ciphersuite_list;
2796 
2797     /* Check whether we have offered this ciphersuite */
2798     for (size_t i = 0; ciphersuite_list[i] != 0; i++) {
2799         if (ciphersuite_list[i] == cipher_suite) {
2800             return 1;
2801         }
2802     }
2803     return 0;
2804 }
2805 
2806 /**
2807  * \brief Validate cipher suite against config in SSL context.
2808  *
2809  * \param ssl              SSL context
2810  * \param suite_info       Cipher suite to validate
2811  * \param min_tls_version  Minimal TLS version to accept a cipher suite
2812  * \param max_tls_version  Maximal TLS version to accept a cipher suite
2813  *
2814  * \return 0 if valid, negative value otherwise.
2815  */
2816 MBEDTLS_CHECK_RETURN_CRITICAL
2817 int mbedtls_ssl_validate_ciphersuite(
2818     const mbedtls_ssl_context *ssl,
2819     const mbedtls_ssl_ciphersuite_t *suite_info,
2820     mbedtls_ssl_protocol_version min_tls_version,
2821     mbedtls_ssl_protocol_version max_tls_version);
2822 
2823 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
2824 MBEDTLS_CHECK_RETURN_CRITICAL
2825 int mbedtls_ssl_parse_server_name_ext(mbedtls_ssl_context *ssl,
2826                                       const unsigned char *buf,
2827                                       const unsigned char *end);
2828 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
2829 
2830 #if defined(MBEDTLS_SSL_RECORD_SIZE_LIMIT)
2831 #define MBEDTLS_SSL_RECORD_SIZE_LIMIT_EXTENSION_DATA_LENGTH (2)
2832 #define MBEDTLS_SSL_RECORD_SIZE_LIMIT_MIN (64)      /* As defined in RFC 8449 */
2833 
2834 MBEDTLS_CHECK_RETURN_CRITICAL
2835 int mbedtls_ssl_tls13_parse_record_size_limit_ext(mbedtls_ssl_context *ssl,
2836                                                   const unsigned char *buf,
2837                                                   const unsigned char *end);
2838 
2839 MBEDTLS_CHECK_RETURN_CRITICAL
2840 int mbedtls_ssl_tls13_write_record_size_limit_ext(mbedtls_ssl_context *ssl,
2841                                                   unsigned char *buf,
2842                                                   const unsigned char *end,
2843                                                   size_t *out_len);
2844 #endif /* MBEDTLS_SSL_RECORD_SIZE_LIMIT */
2845 
2846 #if defined(MBEDTLS_SSL_ALPN)
2847 MBEDTLS_CHECK_RETURN_CRITICAL
2848 int mbedtls_ssl_parse_alpn_ext(mbedtls_ssl_context *ssl,
2849                                const unsigned char *buf,
2850                                const unsigned char *end);
2851 
2852 
2853 MBEDTLS_CHECK_RETURN_CRITICAL
2854 int mbedtls_ssl_write_alpn_ext(mbedtls_ssl_context *ssl,
2855                                unsigned char *buf,
2856                                unsigned char *end,
2857                                size_t *out_len);
2858 #endif /* MBEDTLS_SSL_ALPN */
2859 
2860 #if defined(MBEDTLS_TEST_HOOKS)
2861 int mbedtls_ssl_check_dtls_clihlo_cookie(
2862     mbedtls_ssl_context *ssl,
2863     const unsigned char *cli_id, size_t cli_id_len,
2864     const unsigned char *in, size_t in_len,
2865     unsigned char *obuf, size_t buf_len, size_t *olen);
2866 #endif
2867 
2868 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
2869 /**
2870  * \brief Given an SSL context and its associated configuration, write the TLS
2871  *        1.3 specific Pre-Shared key extension.
2872  *
2873  * \param[in]   ssl     SSL context
2874  * \param[in]   buf     Base address of the buffer where to write the extension
2875  * \param[in]   end     End address of the buffer where to write the extension
2876  * \param[out]  out_len Length in bytes of the Pre-Shared key extension: data
2877  *                      written into the buffer \p buf by this function plus
2878  *                      the length of the binders to be written.
2879  * \param[out]  binders_len Length of the binders to be written at the end of
2880  *                          the extension.
2881  */
2882 MBEDTLS_CHECK_RETURN_CRITICAL
2883 int mbedtls_ssl_tls13_write_identities_of_pre_shared_key_ext(
2884     mbedtls_ssl_context *ssl,
2885     unsigned char *buf, unsigned char *end,
2886     size_t *out_len, size_t *binders_len);
2887 
2888 /**
2889  * \brief Given an SSL context and its associated configuration, write the TLS
2890  *        1.3 specific Pre-Shared key extension binders at the end of the
2891  *        ClientHello.
2892  *
2893  * \param[in]   ssl     SSL context
2894  * \param[in]   buf     Base address of the buffer where to write the binders
2895  * \param[in]   end     End address of the buffer where to write the binders
2896  */
2897 MBEDTLS_CHECK_RETURN_CRITICAL
2898 int mbedtls_ssl_tls13_write_binders_of_pre_shared_key_ext(
2899     mbedtls_ssl_context *ssl,
2900     unsigned char *buf, unsigned char *end);
2901 #endif /* MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED */
2902 
2903 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
2904 /** Get the host name from the SSL context.
2905  *
2906  * \param[in]   ssl     SSL context
2907  *
2908  * \return The \p hostname pointer from the SSL context.
2909  *         \c NULL if mbedtls_ssl_set_hostname() has never been called on
2910  *         \p ssl or if it was last called with \p NULL.
2911  */
2912 const char *mbedtls_ssl_get_hostname_pointer(const mbedtls_ssl_context *ssl);
2913 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
2914 
2915 #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && \
2916     defined(MBEDTLS_SSL_SESSION_TICKETS) && \
2917     defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) && \
2918     defined(MBEDTLS_SSL_CLI_C)
2919 MBEDTLS_CHECK_RETURN_CRITICAL
2920 int mbedtls_ssl_session_set_hostname(mbedtls_ssl_session *session,
2921                                      const char *hostname);
2922 #endif
2923 
2924 #if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_EARLY_DATA) && \
2925     defined(MBEDTLS_SSL_ALPN)
2926 MBEDTLS_CHECK_RETURN_CRITICAL
2927 int mbedtls_ssl_session_set_ticket_alpn(mbedtls_ssl_session *session,
2928                                         const char *alpn);
2929 #endif
2930 
2931 #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS)
2932 
2933 #define MBEDTLS_SSL_TLS1_3_MAX_ALLOWED_TICKET_LIFETIME (604800)
2934 
2935 static inline unsigned int mbedtls_ssl_tls13_session_get_ticket_flags(
2936     mbedtls_ssl_session *session, unsigned int flags)
2937 {
2938     return session->ticket_flags &
2939            (flags & MBEDTLS_SSL_TLS1_3_TICKET_FLAGS_MASK);
2940 }
2941 
2942 /**
2943  * Check if at least one of the given flags is set in
2944  * the session ticket. See the definition of
2945  * `MBEDTLS_SSL_TLS1_3_TICKET_FLAGS_MASK` to get all
2946  * permitted flags.
2947  */
2948 static inline int mbedtls_ssl_tls13_session_ticket_has_flags(
2949     mbedtls_ssl_session *session, unsigned int flags)
2950 {
2951     return mbedtls_ssl_tls13_session_get_ticket_flags(session, flags) != 0;
2952 }
2953 
2954 static inline int mbedtls_ssl_tls13_session_ticket_allow_psk(
2955     mbedtls_ssl_session *session)
2956 {
2957     return mbedtls_ssl_tls13_session_ticket_has_flags(
2958         session, MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_RESUMPTION);
2959 }
2960 
2961 static inline int mbedtls_ssl_tls13_session_ticket_allow_psk_ephemeral(
2962     mbedtls_ssl_session *session)
2963 {
2964     return mbedtls_ssl_tls13_session_ticket_has_flags(
2965         session, MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_EPHEMERAL_RESUMPTION);
2966 }
2967 
2968 static inline unsigned int mbedtls_ssl_tls13_session_ticket_allow_early_data(
2969     mbedtls_ssl_session *session)
2970 {
2971     return mbedtls_ssl_tls13_session_ticket_has_flags(
2972         session, MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_EARLY_DATA);
2973 }
2974 
2975 static inline void mbedtls_ssl_tls13_session_set_ticket_flags(
2976     mbedtls_ssl_session *session, unsigned int flags)
2977 {
2978     session->ticket_flags |= (flags & MBEDTLS_SSL_TLS1_3_TICKET_FLAGS_MASK);
2979 }
2980 
2981 static inline void mbedtls_ssl_tls13_session_clear_ticket_flags(
2982     mbedtls_ssl_session *session, unsigned int flags)
2983 {
2984     session->ticket_flags &= ~(flags & MBEDTLS_SSL_TLS1_3_TICKET_FLAGS_MASK);
2985 }
2986 
2987 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */
2988 
2989 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
2990 #define MBEDTLS_SSL_SESSION_TICKETS_TLS1_2_BIT 0
2991 #define MBEDTLS_SSL_SESSION_TICKETS_TLS1_3_BIT 1
2992 
2993 #define MBEDTLS_SSL_SESSION_TICKETS_TLS1_2_MASK \
2994     (1 << MBEDTLS_SSL_SESSION_TICKETS_TLS1_2_BIT)
2995 #define MBEDTLS_SSL_SESSION_TICKETS_TLS1_3_MASK \
2996     (1 << MBEDTLS_SSL_SESSION_TICKETS_TLS1_3_BIT)
2997 
2998 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
2999 static inline int mbedtls_ssl_conf_get_session_tickets(
3000     const mbedtls_ssl_config *conf)
3001 {
3002     return conf->session_tickets & MBEDTLS_SSL_SESSION_TICKETS_TLS1_2_MASK ?
3003            MBEDTLS_SSL_SESSION_TICKETS_ENABLED :
3004            MBEDTLS_SSL_SESSION_TICKETS_DISABLED;
3005 }
3006 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
3007 
3008 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
3009 static inline int mbedtls_ssl_conf_is_signal_new_session_tickets_enabled(
3010     const mbedtls_ssl_config *conf)
3011 {
3012     return conf->session_tickets & MBEDTLS_SSL_SESSION_TICKETS_TLS1_3_MASK ?
3013            MBEDTLS_SSL_TLS1_3_SIGNAL_NEW_SESSION_TICKETS_ENABLED :
3014            MBEDTLS_SSL_TLS1_3_SIGNAL_NEW_SESSION_TICKETS_DISABLED;
3015 }
3016 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
3017 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
3018 
3019 #if defined(MBEDTLS_SSL_CLI_C) && defined(MBEDTLS_SSL_PROTO_TLS1_3)
3020 int mbedtls_ssl_tls13_finalize_client_hello(mbedtls_ssl_context *ssl);
3021 #endif
3022 
3023 #if defined(MBEDTLS_TEST_HOOKS) && defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC)
3024 
3025 /** Compute the HMAC of variable-length data with constant flow.
3026  *
3027  * This function computes the HMAC of the concatenation of \p add_data and \p
3028  * data, and does with a code flow and memory access pattern that does not
3029  * depend on \p data_len_secret, but only on \p min_data_len and \p
3030  * max_data_len. In particular, this function always reads exactly \p
3031  * max_data_len bytes from \p data.
3032  *
3033  * \param ctx               The HMAC context. It must have keys configured
3034  *                          with mbedtls_md_hmac_starts() and use one of the
3035  *                          following hashes: SHA-384, SHA-256, SHA-1 or MD-5.
3036  *                          It is reset using mbedtls_md_hmac_reset() after
3037  *                          the computation is complete to prepare for the
3038  *                          next computation.
3039  * \param add_data          The first part of the message whose HMAC is being
3040  *                          calculated. This must point to a readable buffer
3041  *                          of \p add_data_len bytes.
3042  * \param add_data_len      The length of \p add_data in bytes.
3043  * \param data              The buffer containing the second part of the
3044  *                          message. This must point to a readable buffer
3045  *                          of \p max_data_len bytes.
3046  * \param data_len_secret   The length of the data to process in \p data.
3047  *                          This must be no less than \p min_data_len and no
3048  *                          greater than \p max_data_len.
3049  * \param min_data_len      The minimal length of the second part of the
3050  *                          message, read from \p data.
3051  * \param max_data_len      The maximal length of the second part of the
3052  *                          message, read from \p data.
3053  * \param output            The HMAC will be written here. This must point to
3054  *                          a writable buffer of sufficient size to hold the
3055  *                          HMAC value.
3056  *
3057  * \retval 0 on success.
3058  * \retval #MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED
3059  *         The hardware accelerator failed.
3060  */
3061 #if defined(MBEDTLS_USE_PSA_CRYPTO)
3062 int mbedtls_ct_hmac(mbedtls_svc_key_id_t key,
3063                     psa_algorithm_t mac_alg,
3064                     const unsigned char *add_data,
3065                     size_t add_data_len,
3066                     const unsigned char *data,
3067                     size_t data_len_secret,
3068                     size_t min_data_len,
3069                     size_t max_data_len,
3070                     unsigned char *output);
3071 #else
3072 int mbedtls_ct_hmac(mbedtls_md_context_t *ctx,
3073                     const unsigned char *add_data,
3074                     size_t add_data_len,
3075                     const unsigned char *data,
3076                     size_t data_len_secret,
3077                     size_t min_data_len,
3078                     size_t max_data_len,
3079                     unsigned char *output);
3080 #endif /* defined(MBEDTLS_USE_PSA_CRYPTO) */
3081 #endif /* MBEDTLS_TEST_HOOKS && defined(MBEDTLS_SSL_SOME_SUITES_USE_MAC) */
3082 
3083 #endif /* ssl_misc.h */
3084