1 /** 2 * \file ssl.h 3 * 4 * \brief SSL/TLS functions. 5 */ 6 /* 7 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved 8 * SPDX-License-Identifier: GPL-2.0 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License along 21 * with this program; if not, write to the Free Software Foundation, Inc., 22 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 23 * 24 * This file is part of mbed TLS (https://tls.mbed.org) 25 */ 26 #ifndef MBEDTLS_SSL_H 27 #define MBEDTLS_SSL_H 28 29 #if !defined(MBEDTLS_CONFIG_FILE) 30 #include "config.h" 31 #else 32 #include MBEDTLS_CONFIG_FILE 33 #endif 34 35 #include "bignum.h" 36 #include "ecp.h" 37 38 #include "ssl_ciphersuites.h" 39 40 #if defined(MBEDTLS_X509_CRT_PARSE_C) 41 #include "x509_crt.h" 42 #include "x509_crl.h" 43 #endif 44 45 #if defined(MBEDTLS_DHM_C) 46 #include "dhm.h" 47 #endif 48 49 #if defined(MBEDTLS_ECDH_C) 50 #include "ecdh.h" 51 #endif 52 53 #if defined(MBEDTLS_ZLIB_SUPPORT) 54 #include "zlib.h" 55 #endif 56 57 #if defined(MBEDTLS_HAVE_TIME) 58 #include "platform_time.h" 59 #endif 60 61 /* 62 * SSL Error codes 63 */ 64 #define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE -0x7080 /**< The requested feature is not available. */ 65 #define MBEDTLS_ERR_SSL_BAD_INPUT_DATA -0x7100 /**< Bad input parameters to function. */ 66 #define MBEDTLS_ERR_SSL_INVALID_MAC -0x7180 /**< Verification of the message MAC failed. */ 67 #define MBEDTLS_ERR_SSL_INVALID_RECORD -0x7200 /**< An invalid SSL record was received. */ 68 #define MBEDTLS_ERR_SSL_CONN_EOF -0x7280 /**< The connection indicated an EOF. */ 69 #define MBEDTLS_ERR_SSL_UNKNOWN_CIPHER -0x7300 /**< An unknown cipher was received. */ 70 #define MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN -0x7380 /**< The server has no ciphersuites in common with the client. */ 71 #define MBEDTLS_ERR_SSL_NO_RNG -0x7400 /**< No RNG was provided to the SSL module. */ 72 #define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE -0x7480 /**< No client certification received from the client, but required by the authentication mode. */ 73 #define MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE -0x7500 /**< Our own certificate(s) is/are too large to send in an SSL message. */ 74 #define MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED -0x7580 /**< The own certificate is not set, but needed by the server. */ 75 #define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED -0x7600 /**< The own private key or pre-shared key is not set, but needed. */ 76 #define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED -0x7680 /**< No CA Chain is set, but required to operate. */ 77 #define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE -0x7700 /**< An unexpected message was received from our peer. */ 78 #define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE -0x7780 /**< A fatal alert message was received from our peer. */ 79 #define MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED -0x7800 /**< Verification of our peer failed. */ 80 #define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY -0x7880 /**< The peer notified us that the connection is going to be closed. */ 81 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO -0x7900 /**< Processing of the ClientHello handshake message failed. */ 82 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO -0x7980 /**< Processing of the ServerHello handshake message failed. */ 83 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE -0x7A00 /**< Processing of the Certificate handshake message failed. */ 84 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST -0x7A80 /**< Processing of the CertificateRequest handshake message failed. */ 85 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE -0x7B00 /**< Processing of the ServerKeyExchange handshake message failed. */ 86 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE -0x7B80 /**< Processing of the ServerHelloDone handshake message failed. */ 87 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE -0x7C00 /**< Processing of the ClientKeyExchange handshake message failed. */ 88 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP -0x7C80 /**< Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Read Public. */ 89 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_CS -0x7D00 /**< Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Calculate Secret. */ 90 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY -0x7D80 /**< Processing of the CertificateVerify handshake message failed. */ 91 #define MBEDTLS_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC -0x7E00 /**< Processing of the ChangeCipherSpec handshake message failed. */ 92 #define MBEDTLS_ERR_SSL_BAD_HS_FINISHED -0x7E80 /**< Processing of the Finished handshake message failed. */ 93 #define MBEDTLS_ERR_SSL_ALLOC_FAILED -0x7F00 /**< Memory allocation failed */ 94 #define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED -0x7F80 /**< Hardware acceleration function returned with error */ 95 #define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH -0x6F80 /**< Hardware acceleration function skipped / left alone data */ 96 #define MBEDTLS_ERR_SSL_COMPRESSION_FAILED -0x6F00 /**< Processing of the compression / decompression failed */ 97 #define MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION -0x6E80 /**< Handshake protocol not within min/max boundaries */ 98 #define MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET -0x6E00 /**< Processing of the NewSessionTicket handshake message failed. */ 99 #define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED -0x6D80 /**< Session ticket has expired. */ 100 #define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH -0x6D00 /**< Public key type mismatch (eg, asked for RSA key exchange and presented EC key) */ 101 #define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY -0x6C80 /**< Unknown identity received (eg, PSK identity) */ 102 #define MBEDTLS_ERR_SSL_INTERNAL_ERROR -0x6C00 /**< Internal error (eg, unexpected failure in lower-level module) */ 103 #define MBEDTLS_ERR_SSL_COUNTER_WRAPPING -0x6B80 /**< A counter would wrap (eg, too many messages exchanged). */ 104 #define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO -0x6B00 /**< Unexpected message at ServerHello in renegotiation. */ 105 #define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED -0x6A80 /**< DTLS client must retry for hello verification */ 106 #define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL -0x6A00 /**< A buffer is too small to receive or write a message */ 107 #define MBEDTLS_ERR_SSL_NO_USABLE_CIPHERSUITE -0x6980 /**< None of the common ciphersuites is usable (eg, no suitable certificate, see debug messages). */ 108 #define MBEDTLS_ERR_SSL_WANT_READ -0x6900 /**< Connection requires a read call. */ 109 #define MBEDTLS_ERR_SSL_WANT_WRITE -0x6880 /**< Connection requires a write call. */ 110 #define MBEDTLS_ERR_SSL_TIMEOUT -0x6800 /**< The operation timed out. */ 111 #define MBEDTLS_ERR_SSL_CLIENT_RECONNECT -0x6780 /**< The client initiated a reconnect from the same port. */ 112 #define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD -0x6700 /**< Record header looks valid but is not expected. */ 113 #define MBEDTLS_ERR_SSL_NON_FATAL -0x6680 /**< The alert message received indicates a non-fatal error. */ 114 #define MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH -0x6600 /**< Couldn't set the hash for verifying CertificateVerify */ 115 116 /* 117 * Various constants 118 */ 119 #define MBEDTLS_SSL_MAJOR_VERSION_3 3 120 #define MBEDTLS_SSL_MINOR_VERSION_0 0 /*!< SSL v3.0 */ 121 #define MBEDTLS_SSL_MINOR_VERSION_1 1 /*!< TLS v1.0 */ 122 #define MBEDTLS_SSL_MINOR_VERSION_2 2 /*!< TLS v1.1 */ 123 #define MBEDTLS_SSL_MINOR_VERSION_3 3 /*!< TLS v1.2 */ 124 125 #define MBEDTLS_SSL_TRANSPORT_STREAM 0 /*!< TLS */ 126 #define MBEDTLS_SSL_TRANSPORT_DATAGRAM 1 /*!< DTLS */ 127 128 #define MBEDTLS_SSL_MAX_HOST_NAME_LEN 255 /*!< Maximum host name defined in RFC 1035 */ 129 130 /* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c 131 * NONE must be zero so that memset()ing structure to zero works */ 132 #define MBEDTLS_SSL_MAX_FRAG_LEN_NONE 0 /*!< don't use this extension */ 133 #define MBEDTLS_SSL_MAX_FRAG_LEN_512 1 /*!< MaxFragmentLength 2^9 */ 134 #define MBEDTLS_SSL_MAX_FRAG_LEN_1024 2 /*!< MaxFragmentLength 2^10 */ 135 #define MBEDTLS_SSL_MAX_FRAG_LEN_2048 3 /*!< MaxFragmentLength 2^11 */ 136 #define MBEDTLS_SSL_MAX_FRAG_LEN_4096 4 /*!< MaxFragmentLength 2^12 */ 137 #define MBEDTLS_SSL_MAX_FRAG_LEN_INVALID 5 /*!< first invalid value */ 138 139 #define MBEDTLS_SSL_IS_CLIENT 0 140 #define MBEDTLS_SSL_IS_SERVER 1 141 142 #define MBEDTLS_SSL_IS_NOT_FALLBACK 0 143 #define MBEDTLS_SSL_IS_FALLBACK 1 144 145 #define MBEDTLS_SSL_EXTENDED_MS_DISABLED 0 146 #define MBEDTLS_SSL_EXTENDED_MS_ENABLED 1 147 148 #define MBEDTLS_SSL_ETM_DISABLED 0 149 #define MBEDTLS_SSL_ETM_ENABLED 1 150 151 #define MBEDTLS_SSL_COMPRESS_NULL 0 152 #define MBEDTLS_SSL_COMPRESS_DEFLATE 1 153 154 #define MBEDTLS_SSL_VERIFY_NONE 0 155 #define MBEDTLS_SSL_VERIFY_OPTIONAL 1 156 #define MBEDTLS_SSL_VERIFY_REQUIRED 2 157 #define MBEDTLS_SSL_VERIFY_UNSET 3 /* Used only for sni_authmode */ 158 159 #define MBEDTLS_SSL_LEGACY_RENEGOTIATION 0 160 #define MBEDTLS_SSL_SECURE_RENEGOTIATION 1 161 162 #define MBEDTLS_SSL_RENEGOTIATION_DISABLED 0 163 #define MBEDTLS_SSL_RENEGOTIATION_ENABLED 1 164 165 #define MBEDTLS_SSL_ANTI_REPLAY_DISABLED 0 166 #define MBEDTLS_SSL_ANTI_REPLAY_ENABLED 1 167 168 #define MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED -1 169 #define MBEDTLS_SSL_RENEGO_MAX_RECORDS_DEFAULT 16 170 171 #define MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION 0 172 #define MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION 1 173 #define MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE 2 174 175 #define MBEDTLS_SSL_TRUNC_HMAC_DISABLED 0 176 #define MBEDTLS_SSL_TRUNC_HMAC_ENABLED 1 177 #define MBEDTLS_SSL_TRUNCATED_HMAC_LEN 10 /* 80 bits, rfc 6066 section 7 */ 178 179 #define MBEDTLS_SSL_SESSION_TICKETS_DISABLED 0 180 #define MBEDTLS_SSL_SESSION_TICKETS_ENABLED 1 181 182 #define MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED 0 183 #define MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED 1 184 185 #define MBEDTLS_SSL_ARC4_ENABLED 0 186 #define MBEDTLS_SSL_ARC4_DISABLED 1 187 188 #define MBEDTLS_SSL_PRESET_DEFAULT 0 189 #define MBEDTLS_SSL_PRESET_SUITEB 2 190 191 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED 1 192 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 0 193 194 /* 195 * Default range for DTLS retransmission timer value, in milliseconds. 196 * RFC 6347 4.2.4.1 says from 1 second to 60 seconds. 197 */ 198 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN 1000 199 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX 60000 200 201 /** 202 * \name SECTION: Module settings 203 * 204 * The configuration options you can set for this module are in this section. 205 * Either change them in config.h or define them on the compiler command line. 206 * \{ 207 */ 208 209 #if !defined(MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME) 210 #define MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME 86400 /**< Lifetime of session tickets (if enabled) */ 211 #endif 212 213 /* 214 * Maxium fragment length in bytes, 215 * determines the size of each of the two internal I/O buffers. 216 * 217 * Note: the RFC defines the default size of SSL / TLS messages. If you 218 * change the value here, other clients / servers may not be able to 219 * communicate with you anymore. Only change this value if you control 220 * both sides of the connection and have it reduced at both sides, or 221 * if you're using the Max Fragment Length extension and you know all your 222 * peers are using it too! 223 */ 224 #if !defined(MBEDTLS_SSL_MAX_CONTENT_LEN) 225 #define MBEDTLS_SSL_MAX_CONTENT_LEN 16384 /**< Size of the input / output buffer */ 226 #endif 227 228 /* \} name SECTION: Module settings */ 229 230 /* 231 * Length of the verify data for secure renegotiation 232 */ 233 #if defined(MBEDTLS_SSL_PROTO_SSL3) 234 #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 36 235 #else 236 #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 12 237 #endif 238 239 /* 240 * Signaling ciphersuite values (SCSV) 241 */ 242 #define MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO 0xFF /**< renegotiation info ext */ 243 #define MBEDTLS_SSL_FALLBACK_SCSV_VALUE 0x5600 /**< RFC 7507 section 2 */ 244 245 /* 246 * Supported Signature and Hash algorithms (For TLS 1.2) 247 * RFC 5246 section 7.4.1.4.1 248 */ 249 #define MBEDTLS_SSL_HASH_NONE 0 250 #define MBEDTLS_SSL_HASH_MD5 1 251 #define MBEDTLS_SSL_HASH_SHA1 2 252 #define MBEDTLS_SSL_HASH_SHA224 3 253 #define MBEDTLS_SSL_HASH_SHA256 4 254 #define MBEDTLS_SSL_HASH_SHA384 5 255 #define MBEDTLS_SSL_HASH_SHA512 6 256 257 #define MBEDTLS_SSL_SIG_ANON 0 258 #define MBEDTLS_SSL_SIG_RSA 1 259 #define MBEDTLS_SSL_SIG_ECDSA 3 260 261 /* 262 * Client Certificate Types 263 * RFC 5246 section 7.4.4 plus RFC 4492 section 5.5 264 */ 265 #define MBEDTLS_SSL_CERT_TYPE_RSA_SIGN 1 266 #define MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN 64 267 268 /* 269 * Message, alert and handshake types 270 */ 271 #define MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC 20 272 #define MBEDTLS_SSL_MSG_ALERT 21 273 #define MBEDTLS_SSL_MSG_HANDSHAKE 22 274 #define MBEDTLS_SSL_MSG_APPLICATION_DATA 23 275 276 #define MBEDTLS_SSL_ALERT_LEVEL_WARNING 1 277 #define MBEDTLS_SSL_ALERT_LEVEL_FATAL 2 278 279 #define MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY 0 /* 0x00 */ 280 #define MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE 10 /* 0x0A */ 281 #define MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC 20 /* 0x14 */ 282 #define MBEDTLS_SSL_ALERT_MSG_DECRYPTION_FAILED 21 /* 0x15 */ 283 #define MBEDTLS_SSL_ALERT_MSG_RECORD_OVERFLOW 22 /* 0x16 */ 284 #define MBEDTLS_SSL_ALERT_MSG_DECOMPRESSION_FAILURE 30 /* 0x1E */ 285 #define MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE 40 /* 0x28 */ 286 #define MBEDTLS_SSL_ALERT_MSG_NO_CERT 41 /* 0x29 */ 287 #define MBEDTLS_SSL_ALERT_MSG_BAD_CERT 42 /* 0x2A */ 288 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT 43 /* 0x2B */ 289 #define MBEDTLS_SSL_ALERT_MSG_CERT_REVOKED 44 /* 0x2C */ 290 #define MBEDTLS_SSL_ALERT_MSG_CERT_EXPIRED 45 /* 0x2D */ 291 #define MBEDTLS_SSL_ALERT_MSG_CERT_UNKNOWN 46 /* 0x2E */ 292 #define MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER 47 /* 0x2F */ 293 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_CA 48 /* 0x30 */ 294 #define MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED 49 /* 0x31 */ 295 #define MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR 50 /* 0x32 */ 296 #define MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR 51 /* 0x33 */ 297 #define MBEDTLS_SSL_ALERT_MSG_EXPORT_RESTRICTION 60 /* 0x3C */ 298 #define MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION 70 /* 0x46 */ 299 #define MBEDTLS_SSL_ALERT_MSG_INSUFFICIENT_SECURITY 71 /* 0x47 */ 300 #define MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR 80 /* 0x50 */ 301 #define MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK 86 /* 0x56 */ 302 #define MBEDTLS_SSL_ALERT_MSG_USER_CANCELED 90 /* 0x5A */ 303 #define MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION 100 /* 0x64 */ 304 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT 110 /* 0x6E */ 305 #define MBEDTLS_SSL_ALERT_MSG_UNRECOGNIZED_NAME 112 /* 0x70 */ 306 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY 115 /* 0x73 */ 307 #define MBEDTLS_SSL_ALERT_MSG_NO_APPLICATION_PROTOCOL 120 /* 0x78 */ 308 309 #define MBEDTLS_SSL_HS_HELLO_REQUEST 0 310 #define MBEDTLS_SSL_HS_CLIENT_HELLO 1 311 #define MBEDTLS_SSL_HS_SERVER_HELLO 2 312 #define MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST 3 313 #define MBEDTLS_SSL_HS_NEW_SESSION_TICKET 4 314 #define MBEDTLS_SSL_HS_CERTIFICATE 11 315 #define MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE 12 316 #define MBEDTLS_SSL_HS_CERTIFICATE_REQUEST 13 317 #define MBEDTLS_SSL_HS_SERVER_HELLO_DONE 14 318 #define MBEDTLS_SSL_HS_CERTIFICATE_VERIFY 15 319 #define MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE 16 320 #define MBEDTLS_SSL_HS_FINISHED 20 321 322 /* 323 * TLS extensions 324 */ 325 #define MBEDTLS_TLS_EXT_SERVERNAME 0 326 #define MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME 0 327 328 #define MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH 1 329 330 #define MBEDTLS_TLS_EXT_TRUNCATED_HMAC 4 331 332 #define MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES 10 333 #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS 11 334 335 #define MBEDTLS_TLS_EXT_SIG_ALG 13 336 337 #define MBEDTLS_TLS_EXT_ALPN 16 338 339 #define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC 22 /* 0x16 */ 340 #define MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET 0x0017 /* 23 */ 341 342 #define MBEDTLS_TLS_EXT_SESSION_TICKET 35 343 344 #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP 256 /* experimental */ 345 346 #define MBEDTLS_TLS_EXT_RENEGOTIATION_INFO 0xFF01 347 348 /* 349 * Size defines 350 */ 351 #if !defined(MBEDTLS_PSK_MAX_LEN) 352 #define MBEDTLS_PSK_MAX_LEN 32 /* 256 bits */ 353 #endif 354 355 /* Dummy type used only for its size */ 356 union mbedtls_ssl_premaster_secret 357 { 358 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) 359 unsigned char _pms_rsa[48]; /* RFC 5246 8.1.1 */ 360 #endif 361 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) 362 unsigned char _pms_dhm[MBEDTLS_MPI_MAX_SIZE]; /* RFC 5246 8.1.2 */ 363 #endif 364 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ 365 defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ 366 defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ 367 defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) 368 unsigned char _pms_ecdh[MBEDTLS_ECP_MAX_BYTES]; /* RFC 4492 5.10 */ 369 #endif 370 #if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) 371 unsigned char _pms_psk[4 + 2 * MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 2 */ 372 #endif 373 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) 374 unsigned char _pms_dhe_psk[4 + MBEDTLS_MPI_MAX_SIZE 375 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 3 */ 376 #endif 377 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) 378 unsigned char _pms_rsa_psk[52 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 4 */ 379 #endif 380 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) 381 unsigned char _pms_ecdhe_psk[4 + MBEDTLS_ECP_MAX_BYTES 382 + MBEDTLS_PSK_MAX_LEN]; /* RFC 5489 2 */ 383 #endif 384 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) 385 unsigned char _pms_ecjpake[32]; /* Thread spec: SHA-256 output */ 386 #endif 387 }; 388 389 #define MBEDTLS_PREMASTER_SIZE sizeof( union mbedtls_ssl_premaster_secret ) 390 391 #ifdef __cplusplus 392 extern "C" { 393 #endif 394 395 /* 396 * SSL state machine 397 */ 398 typedef enum 399 { 400 MBEDTLS_SSL_HELLO_REQUEST, 401 MBEDTLS_SSL_CLIENT_HELLO, 402 MBEDTLS_SSL_SERVER_HELLO, 403 MBEDTLS_SSL_SERVER_CERTIFICATE, 404 MBEDTLS_SSL_SERVER_KEY_EXCHANGE, 405 MBEDTLS_SSL_CERTIFICATE_REQUEST, 406 MBEDTLS_SSL_SERVER_HELLO_DONE, 407 MBEDTLS_SSL_CLIENT_CERTIFICATE, 408 MBEDTLS_SSL_CLIENT_KEY_EXCHANGE, 409 MBEDTLS_SSL_CERTIFICATE_VERIFY, 410 MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC, 411 MBEDTLS_SSL_CLIENT_FINISHED, 412 MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC, 413 MBEDTLS_SSL_SERVER_FINISHED, 414 MBEDTLS_SSL_FLUSH_BUFFERS, 415 MBEDTLS_SSL_HANDSHAKE_WRAPUP, 416 MBEDTLS_SSL_HANDSHAKE_OVER, 417 MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET, 418 MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT, 419 } 420 mbedtls_ssl_states; 421 422 /** 423 * \brief Callback type: send data on the network. 424 * 425 * \note That callback may be either blocking or non-blocking. 426 * 427 * \param ctx Context for the send callback (typically a file descriptor) 428 * \param buf Buffer holding the data to send 429 * \param len Length of the data to send 430 * 431 * \return The callback must return the number of bytes sent if any, 432 * or a non-zero error code. 433 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_WRITE 434 * must be returned when the operation would block. 435 * 436 * \note The callback is allowed to send fewer bytes than requested. 437 * It must always return the number of bytes actually sent. 438 */ 439 typedef int mbedtls_ssl_send_t( void *ctx, 440 const unsigned char *buf, 441 size_t len ); 442 443 /** 444 * \brief Callback type: receive data from the network. 445 * 446 * \note That callback may be either blocking or non-blocking. 447 * 448 * \param ctx Context for the receive callback (typically a file 449 * descriptor) 450 * \param buf Buffer to write the received data to 451 * \param len Length of the receive buffer 452 * 453 * \return The callback must return the number of bytes received, 454 * or a non-zero error code. 455 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ 456 * must be returned when the operation would block. 457 * 458 * \note The callback may receive fewer bytes than the length of the 459 * buffer. It must always return the number of bytes actually 460 * received and written to the buffer. 461 */ 462 typedef int mbedtls_ssl_recv_t( void *ctx, 463 unsigned char *buf, 464 size_t len ); 465 466 /** 467 * \brief Callback type: receive data from the network, with timeout 468 * 469 * \note That callback must block until data is received, or the 470 * timeout delay expires, or the operation is interrupted by a 471 * signal. 472 * 473 * \param ctx Context for the receive callback (typically a file descriptor) 474 * \param buf Buffer to write the received data to 475 * \param len Length of the receive buffer 476 * \param timeout Maximum nomber of millisecondes to wait for data 477 * 0 means no timeout (potentially waiting forever) 478 * 479 * \return The callback must return the number of bytes received, 480 * or a non-zero error code: 481 * \c MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out, 482 * \c MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal. 483 * 484 * \note The callback may receive fewer bytes than the length of the 485 * buffer. It must always return the number of bytes actually 486 * received and written to the buffer. 487 */ 488 typedef int mbedtls_ssl_recv_timeout_t( void *ctx, 489 unsigned char *buf, 490 size_t len, 491 uint32_t timeout ); 492 /** 493 * \brief Callback type: set a pair of timers/delays to watch 494 * 495 * \param ctx Context pointer 496 * \param int_ms Intermediate delay in milliseconds 497 * \param fin_ms Final delay in milliseconds 498 * 0 cancels the current timer. 499 * 500 * \note This callback must at least store the necessary information 501 * for the associated \c mbedtls_ssl_get_timer_t callback to 502 * return correct information. 503 * 504 * \note If using a event-driven style of programming, an event must 505 * be generated when the final delay is passed. The event must 506 * cause a call to \c mbedtls_ssl_handshake() with the proper 507 * SSL context to be scheduled. Care must be taken to ensure 508 * that at most one such call happens at a time. 509 * 510 * \note Only one timer at a time must be running. Calling this 511 * function while a timer is running must cancel it. Cancelled 512 * timers must not generate any event. 513 */ 514 typedef void mbedtls_ssl_set_timer_t( void * ctx, 515 uint32_t int_ms, 516 uint32_t fin_ms ); 517 518 /** 519 * \brief Callback type: get status of timers/delays 520 * 521 * \param ctx Context pointer 522 * 523 * \return This callback must return: 524 * -1 if cancelled (fin_ms == 0), 525 * 0 if none of the delays have passed, 526 * 1 if only the intermediate delay has passed, 527 * 2 if the final delay has passed. 528 */ 529 typedef int mbedtls_ssl_get_timer_t( void * ctx ); 530 531 532 /* Defined below */ 533 typedef struct mbedtls_ssl_session mbedtls_ssl_session; 534 typedef struct mbedtls_ssl_context mbedtls_ssl_context; 535 typedef struct mbedtls_ssl_config mbedtls_ssl_config; 536 537 /* Defined in ssl_internal.h */ 538 typedef struct mbedtls_ssl_transform mbedtls_ssl_transform; 539 typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params; 540 typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t; 541 #if defined(MBEDTLS_X509_CRT_PARSE_C) 542 typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert; 543 #endif 544 #if defined(MBEDTLS_SSL_PROTO_DTLS) 545 typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item; 546 #endif 547 548 /* 549 * This structure is used for storing current session data. 550 */ 551 struct mbedtls_ssl_session 552 { 553 #if defined(MBEDTLS_HAVE_TIME) 554 mbedtls_time_t start; /*!< starting time */ 555 #endif 556 int ciphersuite; /*!< chosen ciphersuite */ 557 int compression; /*!< chosen compression */ 558 size_t id_len; /*!< session id length */ 559 unsigned char id[32]; /*!< session identifier */ 560 unsigned char master[48]; /*!< the master secret */ 561 562 #if defined(MBEDTLS_X509_CRT_PARSE_C) 563 mbedtls_x509_crt *peer_cert; /*!< peer X.509 cert chain */ 564 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 565 uint32_t verify_result; /*!< verification result */ 566 567 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C) 568 unsigned char *ticket; /*!< RFC 5077 session ticket */ 569 size_t ticket_len; /*!< session ticket length */ 570 uint32_t ticket_lifetime; /*!< ticket lifetime hint */ 571 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */ 572 573 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) 574 unsigned char mfl_code; /*!< MaxFragmentLength negotiated by peer */ 575 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ 576 577 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC) 578 int trunc_hmac; /*!< flag for truncated hmac activation */ 579 #endif /* MBEDTLS_SSL_TRUNCATED_HMAC */ 580 581 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) 582 int encrypt_then_mac; /*!< flag for EtM activation */ 583 #endif 584 }; 585 586 /** 587 * SSL/TLS configuration to be shared between mbedtls_ssl_context structures. 588 */ 589 struct mbedtls_ssl_config 590 { 591 /* Group items by size (largest first) to minimize padding overhead */ 592 593 /* 594 * Pointers 595 */ 596 597 const int *ciphersuite_list[4]; /*!< allowed ciphersuites per version */ 598 599 /** Callback for printing debug output */ 600 void (*f_dbg)(void *, int, const char *, int, const char *); 601 void *p_dbg; /*!< context for the debug function */ 602 603 /** Callback for getting (pseudo-)random numbers */ 604 int (*f_rng)(void *, unsigned char *, size_t); 605 void *p_rng; /*!< context for the RNG function */ 606 607 /** Callback to retrieve a session from the cache */ 608 int (*f_get_cache)(void *, mbedtls_ssl_session *); 609 /** Callback to store a session into the cache */ 610 int (*f_set_cache)(void *, const mbedtls_ssl_session *); 611 void *p_cache; /*!< context for cache callbacks */ 612 613 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) 614 /** Callback for setting cert according to SNI extension */ 615 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, size_t); 616 void *p_sni; /*!< context for SNI callback */ 617 #endif 618 619 #if defined(MBEDTLS_X509_CRT_PARSE_C) 620 /** Callback to customize X.509 certificate chain verification */ 621 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *); 622 void *p_vrfy; /*!< context for X.509 verify calllback */ 623 #endif 624 625 #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) 626 /** Callback to retrieve PSK key from identity */ 627 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, size_t); 628 void *p_psk; /*!< context for PSK callback */ 629 #endif 630 631 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) 632 /** Callback to create & write a cookie for ClientHello veirifcation */ 633 int (*f_cookie_write)( void *, unsigned char **, unsigned char *, 634 const unsigned char *, size_t ); 635 /** Callback to verify validity of a ClientHello cookie */ 636 int (*f_cookie_check)( void *, const unsigned char *, size_t, 637 const unsigned char *, size_t ); 638 void *p_cookie; /*!< context for the cookie callbacks */ 639 #endif 640 641 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C) 642 /** Callback to create & write a session ticket */ 643 int (*f_ticket_write)( void *, const mbedtls_ssl_session *, 644 unsigned char *, const unsigned char *, size_t *, uint32_t * ); 645 /** Callback to parse a session ticket into a session structure */ 646 int (*f_ticket_parse)( void *, mbedtls_ssl_session *, unsigned char *, size_t); 647 void *p_ticket; /*!< context for the ticket callbacks */ 648 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */ 649 650 #if defined(MBEDTLS_SSL_EXPORT_KEYS) 651 /** Callback to export key block and master secret */ 652 int (*f_export_keys)( void *, const unsigned char *, 653 const unsigned char *, size_t, size_t, size_t ); 654 void *p_export_keys; /*!< context for key export callback */ 655 #endif 656 657 #if defined(MBEDTLS_X509_CRT_PARSE_C) 658 const mbedtls_x509_crt_profile *cert_profile; /*!< verification profile */ 659 mbedtls_ssl_key_cert *key_cert; /*!< own certificate/key pair(s) */ 660 mbedtls_x509_crt *ca_chain; /*!< trusted CAs */ 661 mbedtls_x509_crl *ca_crl; /*!< trusted CAs CRLs */ 662 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 663 664 #if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) 665 const int *sig_hashes; /*!< allowed signature hashes */ 666 #endif 667 668 #if defined(MBEDTLS_ECP_C) 669 const mbedtls_ecp_group_id *curve_list; /*!< allowed curves */ 670 #endif 671 672 #if defined(MBEDTLS_DHM_C) 673 mbedtls_mpi dhm_P; /*!< prime modulus for DHM */ 674 mbedtls_mpi dhm_G; /*!< generator for DHM */ 675 #endif 676 677 #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) 678 unsigned char *psk; /*!< pre-shared key */ 679 size_t psk_len; /*!< length of the pre-shared key */ 680 unsigned char *psk_identity; /*!< identity for PSK negotiation */ 681 size_t psk_identity_len;/*!< length of identity */ 682 #endif 683 684 #if defined(MBEDTLS_SSL_ALPN) 685 const char **alpn_list; /*!< ordered list of protocols */ 686 #endif 687 688 /* 689 * Numerical settings (int then char) 690 */ 691 692 uint32_t read_timeout; /*!< timeout for mbedtls_ssl_read (ms) */ 693 694 #if defined(MBEDTLS_SSL_PROTO_DTLS) 695 uint32_t hs_timeout_min; /*!< initial value of the handshake 696 retransmission timeout (ms) */ 697 uint32_t hs_timeout_max; /*!< maximum value of the handshake 698 retransmission timeout (ms) */ 699 #endif 700 701 #if defined(MBEDTLS_SSL_RENEGOTIATION) 702 int renego_max_records; /*!< grace period for renegotiation */ 703 unsigned char renego_period[8]; /*!< value of the record counters 704 that triggers renegotiation */ 705 #endif 706 707 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT) 708 unsigned int badmac_limit; /*!< limit of records with a bad MAC */ 709 #endif 710 711 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C) 712 unsigned int dhm_min_bitlen; /*!< min. bit length of the DHM prime */ 713 #endif 714 715 unsigned char max_major_ver; /*!< max. major version used */ 716 unsigned char max_minor_ver; /*!< max. minor version used */ 717 unsigned char min_major_ver; /*!< min. major version used */ 718 unsigned char min_minor_ver; /*!< min. minor version used */ 719 720 /* 721 * Flags (bitfields) 722 */ 723 724 unsigned int endpoint : 1; /*!< 0: client, 1: server */ 725 unsigned int transport : 1; /*!< stream (TLS) or datagram (DTLS) */ 726 unsigned int authmode : 2; /*!< MBEDTLS_SSL_VERIFY_XXX */ 727 /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE */ 728 unsigned int allow_legacy_renegotiation : 2 ; /*!< MBEDTLS_LEGACY_XXX */ 729 #if defined(MBEDTLS_ARC4_C) 730 unsigned int arc4_disabled : 1; /*!< blacklist RC4 ciphersuites? */ 731 #endif 732 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) 733 unsigned int mfl_code : 3; /*!< desired fragment length */ 734 #endif 735 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) 736 unsigned int encrypt_then_mac : 1 ; /*!< negotiate encrypt-then-mac? */ 737 #endif 738 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) 739 unsigned int extended_ms : 1; /*!< negotiate extended master secret? */ 740 #endif 741 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) 742 unsigned int anti_replay : 1; /*!< detect and prevent replay? */ 743 #endif 744 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING) 745 unsigned int cbc_record_splitting : 1; /*!< do cbc record splitting */ 746 #endif 747 #if defined(MBEDTLS_SSL_RENEGOTIATION) 748 unsigned int disable_renegotiation : 1; /*!< disable renegotiation? */ 749 #endif 750 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC) 751 unsigned int trunc_hmac : 1; /*!< negotiate truncated hmac? */ 752 #endif 753 #if defined(MBEDTLS_SSL_SESSION_TICKETS) 754 unsigned int session_tickets : 1; /*!< use session tickets? */ 755 #endif 756 #if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C) 757 unsigned int fallback : 1; /*!< is this a fallback? */ 758 #endif 759 #if defined(MBEDTLS_SSL_SRV_C) 760 unsigned int cert_req_ca_list : 1; /*!< enable sending CA list in 761 Certificate Request messages? */ 762 #endif 763 }; 764 765 766 struct mbedtls_ssl_context 767 { 768 const mbedtls_ssl_config *conf; /*!< configuration information */ 769 770 /* 771 * Miscellaneous 772 */ 773 int state; /*!< SSL handshake: current state */ 774 #if defined(MBEDTLS_SSL_RENEGOTIATION) 775 int renego_status; /*!< Initial, in progress, pending? */ 776 int renego_records_seen; /*!< Records since renego request, or with DTLS, 777 number of retransmissions of request if 778 renego_max_records is < 0 */ 779 #endif 780 781 int major_ver; /*!< equal to MBEDTLS_SSL_MAJOR_VERSION_3 */ 782 int minor_ver; /*!< either 0 (SSL3) or 1 (TLS1.0) */ 783 784 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT) 785 unsigned badmac_seen; /*!< records with a bad MAC received */ 786 #endif 787 788 mbedtls_ssl_send_t *f_send; /*!< Callback for network send */ 789 mbedtls_ssl_recv_t *f_recv; /*!< Callback for network receive */ 790 mbedtls_ssl_recv_timeout_t *f_recv_timeout; 791 /*!< Callback for network receive with timeout */ 792 793 void *p_bio; /*!< context for I/O operations */ 794 795 /* 796 * Session layer 797 */ 798 mbedtls_ssl_session *session_in; /*!< current session data (in) */ 799 mbedtls_ssl_session *session_out; /*!< current session data (out) */ 800 mbedtls_ssl_session *session; /*!< negotiated session data */ 801 mbedtls_ssl_session *session_negotiate; /*!< session data in negotiation */ 802 803 mbedtls_ssl_handshake_params *handshake; /*!< params required only during 804 the handshake process */ 805 806 /* 807 * Record layer transformations 808 */ 809 mbedtls_ssl_transform *transform_in; /*!< current transform params (in) */ 810 mbedtls_ssl_transform *transform_out; /*!< current transform params (in) */ 811 mbedtls_ssl_transform *transform; /*!< negotiated transform params */ 812 mbedtls_ssl_transform *transform_negotiate; /*!< transform params in negotiation */ 813 814 /* 815 * Timers 816 */ 817 void *p_timer; /*!< context for the timer callbacks */ 818 819 mbedtls_ssl_set_timer_t *f_set_timer; /*!< set timer callback */ 820 mbedtls_ssl_get_timer_t *f_get_timer; /*!< get timer callback */ 821 822 /* 823 * Record layer (incoming data) 824 */ 825 unsigned char *in_buf; /*!< input buffer */ 826 unsigned char *in_ctr; /*!< 64-bit incoming message counter 827 TLS: maintained by us 828 DTLS: read from peer */ 829 unsigned char *in_hdr; /*!< start of record header */ 830 unsigned char *in_len; /*!< two-bytes message length field */ 831 unsigned char *in_iv; /*!< ivlen-byte IV */ 832 unsigned char *in_msg; /*!< message contents (in_iv+ivlen) */ 833 unsigned char *in_offt; /*!< read offset in application data */ 834 835 int in_msgtype; /*!< record header: message type */ 836 size_t in_msglen; /*!< record header: message length */ 837 size_t in_left; /*!< amount of data read so far */ 838 #if defined(MBEDTLS_SSL_PROTO_DTLS) 839 uint16_t in_epoch; /*!< DTLS epoch for incoming records */ 840 size_t next_record_offset; /*!< offset of the next record in datagram 841 (equal to in_left if none) */ 842 #endif 843 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) 844 uint64_t in_window_top; /*!< last validated record seq_num */ 845 uint64_t in_window; /*!< bitmask for replay detection */ 846 #endif 847 848 size_t in_hslen; /*!< current handshake message length, 849 including the handshake header */ 850 int nb_zero; /*!< # of 0-length encrypted messages */ 851 852 int keep_current_message; /*!< drop or reuse current message 853 on next call to record layer? */ 854 855 /* 856 * Record layer (outgoing data) 857 */ 858 unsigned char *out_buf; /*!< output buffer */ 859 unsigned char *out_ctr; /*!< 64-bit outgoing message counter */ 860 unsigned char *out_hdr; /*!< start of record header */ 861 unsigned char *out_len; /*!< two-bytes message length field */ 862 unsigned char *out_iv; /*!< ivlen-byte IV */ 863 unsigned char *out_msg; /*!< message contents (out_iv+ivlen) */ 864 865 int out_msgtype; /*!< record header: message type */ 866 size_t out_msglen; /*!< record header: message length */ 867 size_t out_left; /*!< amount of data not yet written */ 868 869 #if defined(MBEDTLS_ZLIB_SUPPORT) 870 unsigned char *compress_buf; /*!< zlib data buffer */ 871 #endif 872 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING) 873 signed char split_done; /*!< current record already splitted? */ 874 #endif 875 876 /* 877 * PKI layer 878 */ 879 int client_auth; /*!< flag for client auth. */ 880 881 /* 882 * User settings 883 */ 884 #if defined(MBEDTLS_X509_CRT_PARSE_C) 885 char *hostname; /*!< expected peer CN for verification 886 (and SNI if available) */ 887 #endif 888 889 #if defined(MBEDTLS_SSL_ALPN) 890 const char *alpn_chosen; /*!< negotiated protocol */ 891 #endif 892 893 /* 894 * Information for DTLS hello verify 895 */ 896 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) 897 unsigned char *cli_id; /*!< transport-level ID of the client */ 898 size_t cli_id_len; /*!< length of cli_id */ 899 #endif 900 901 /* 902 * Secure renegotiation 903 */ 904 /* needed to know when to send extension on server */ 905 int secure_renegotiation; /*!< does peer support legacy or 906 secure renegotiation */ 907 #if defined(MBEDTLS_SSL_RENEGOTIATION) 908 size_t verify_data_len; /*!< length of verify data stored */ 909 char own_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */ 910 char peer_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */ 911 #endif 912 }; 913 914 #if defined(MBEDTLS_SSL_HW_RECORD_ACCEL) 915 916 #define MBEDTLS_SSL_CHANNEL_OUTBOUND 0 917 #define MBEDTLS_SSL_CHANNEL_INBOUND 1 918 919 extern int (*mbedtls_ssl_hw_record_init)(mbedtls_ssl_context *ssl, 920 const unsigned char *key_enc, const unsigned char *key_dec, 921 size_t keylen, 922 const unsigned char *iv_enc, const unsigned char *iv_dec, 923 size_t ivlen, 924 const unsigned char *mac_enc, const unsigned char *mac_dec, 925 size_t maclen); 926 extern int (*mbedtls_ssl_hw_record_activate)(mbedtls_ssl_context *ssl, int direction); 927 extern int (*mbedtls_ssl_hw_record_reset)(mbedtls_ssl_context *ssl); 928 extern int (*mbedtls_ssl_hw_record_write)(mbedtls_ssl_context *ssl); 929 extern int (*mbedtls_ssl_hw_record_read)(mbedtls_ssl_context *ssl); 930 extern int (*mbedtls_ssl_hw_record_finish)(mbedtls_ssl_context *ssl); 931 #endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */ 932 933 /** 934 * \brief Return the name of the ciphersuite associated with the 935 * given ID 936 * 937 * \param ciphersuite_id SSL ciphersuite ID 938 * 939 * \return a string containing the ciphersuite name 940 */ 941 const char *mbedtls_ssl_get_ciphersuite_name( const int ciphersuite_id ); 942 943 /** 944 * \brief Return the ID of the ciphersuite associated with the 945 * given name 946 * 947 * \param ciphersuite_name SSL ciphersuite name 948 * 949 * \return the ID with the ciphersuite or 0 if not found 950 */ 951 int mbedtls_ssl_get_ciphersuite_id( const char *ciphersuite_name ); 952 953 /** 954 * \brief Initialize an SSL context 955 * Just makes the context ready for mbedtls_ssl_setup() or 956 * mbedtls_ssl_free() 957 * 958 * \param ssl SSL context 959 */ 960 void mbedtls_ssl_init( mbedtls_ssl_context *ssl ); 961 962 /** 963 * \brief Set up an SSL context for use 964 * 965 * \note No copy of the configuration context is made, it can be 966 * shared by many mbedtls_ssl_context structures. 967 * 968 * \warning The conf structure will be accessed during the session. 969 * It must not be modified or freed as long as the session 970 * is active. 971 * 972 * \warning This function must be called exactly once per context. 973 * Calling mbedtls_ssl_setup again is not supported, even 974 * if no session is active. 975 * 976 * \param ssl SSL context 977 * \param conf SSL configuration to use 978 * 979 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED if 980 * memory allocation failed 981 */ 982 int mbedtls_ssl_setup( mbedtls_ssl_context *ssl, 983 const mbedtls_ssl_config *conf ); 984 985 /** 986 * \brief Reset an already initialized SSL context for re-use 987 * while retaining application-set variables, function 988 * pointers and data. 989 * 990 * \param ssl SSL context 991 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED, 992 MBEDTLS_ERR_SSL_HW_ACCEL_FAILED or 993 * MBEDTLS_ERR_SSL_COMPRESSION_FAILED 994 */ 995 int mbedtls_ssl_session_reset( mbedtls_ssl_context *ssl ); 996 997 /** 998 * \brief Set the current endpoint type 999 * 1000 * \param conf SSL configuration 1001 * \param endpoint must be MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER 1002 */ 1003 void mbedtls_ssl_conf_endpoint( mbedtls_ssl_config *conf, int endpoint ); 1004 1005 /** 1006 * \brief Set the transport type (TLS or DTLS). 1007 * Default: TLS 1008 * 1009 * \note For DTLS, you must either provide a recv callback that 1010 * doesn't block, or one that handles timeouts, see 1011 * \c mbedtls_ssl_set_bio(). You also need to provide timer 1012 * callbacks with \c mbedtls_ssl_set_timer_cb(). 1013 * 1014 * \param conf SSL configuration 1015 * \param transport transport type: 1016 * MBEDTLS_SSL_TRANSPORT_STREAM for TLS, 1017 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS. 1018 */ 1019 void mbedtls_ssl_conf_transport( mbedtls_ssl_config *conf, int transport ); 1020 1021 /** 1022 * \brief Set the certificate verification mode 1023 * Default: NONE on server, REQUIRED on client 1024 * 1025 * \param conf SSL configuration 1026 * \param authmode can be: 1027 * 1028 * MBEDTLS_SSL_VERIFY_NONE: peer certificate is not checked 1029 * (default on server) 1030 * (insecure on client) 1031 * 1032 * MBEDTLS_SSL_VERIFY_OPTIONAL: peer certificate is checked, however the 1033 * handshake continues even if verification failed; 1034 * mbedtls_ssl_get_verify_result() can be called after the 1035 * handshake is complete. 1036 * 1037 * MBEDTLS_SSL_VERIFY_REQUIRED: peer *must* present a valid certificate, 1038 * handshake is aborted if verification failed. 1039 * (default on client) 1040 * 1041 * \note On client, MBEDTLS_SSL_VERIFY_REQUIRED is the recommended mode. 1042 * With MBEDTLS_SSL_VERIFY_OPTIONAL, the user needs to call mbedtls_ssl_get_verify_result() at 1043 * the right time(s), which may not be obvious, while REQUIRED always perform 1044 * the verification as soon as possible. For example, REQUIRED was protecting 1045 * against the "triple handshake" attack even before it was found. 1046 */ 1047 void mbedtls_ssl_conf_authmode( mbedtls_ssl_config *conf, int authmode ); 1048 1049 #if defined(MBEDTLS_X509_CRT_PARSE_C) 1050 /** 1051 * \brief Set the verification callback (Optional). 1052 * 1053 * If set, the verify callback is called for each 1054 * certificate in the chain. For implementation 1055 * information, please see \c mbedtls_x509_crt_verify() 1056 * 1057 * \param conf SSL configuration 1058 * \param f_vrfy verification function 1059 * \param p_vrfy verification parameter 1060 */ 1061 void mbedtls_ssl_conf_verify( mbedtls_ssl_config *conf, 1062 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *), 1063 void *p_vrfy ); 1064 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 1065 1066 /** 1067 * \brief Set the random number generator callback 1068 * 1069 * \param conf SSL configuration 1070 * \param f_rng RNG function 1071 * \param p_rng RNG parameter 1072 */ 1073 void mbedtls_ssl_conf_rng( mbedtls_ssl_config *conf, 1074 int (*f_rng)(void *, unsigned char *, size_t), 1075 void *p_rng ); 1076 1077 /** 1078 * \brief Set the debug callback 1079 * 1080 * The callback has the following argument: 1081 * void * opaque context for the callback 1082 * int debug level 1083 * const char * file name 1084 * int line number 1085 * const char * message 1086 * 1087 * \param conf SSL configuration 1088 * \param f_dbg debug function 1089 * \param p_dbg debug parameter 1090 */ 1091 void mbedtls_ssl_conf_dbg( mbedtls_ssl_config *conf, 1092 void (*f_dbg)(void *, int, const char *, int, const char *), 1093 void *p_dbg ); 1094 1095 /** 1096 * \brief Set the underlying BIO callbacks for write, read and 1097 * read-with-timeout. 1098 * 1099 * \param ssl SSL context 1100 * \param p_bio parameter (context) shared by BIO callbacks 1101 * \param f_send write callback 1102 * \param f_recv read callback 1103 * \param f_recv_timeout blocking read callback with timeout. 1104 * 1105 * \note One of f_recv or f_recv_timeout can be NULL, in which case 1106 * the other is used. If both are non-NULL, f_recv_timeout is 1107 * used and f_recv is ignored (as if it were NULL). 1108 * 1109 * \note The two most common use cases are: 1110 * - non-blocking I/O, f_recv != NULL, f_recv_timeout == NULL 1111 * - blocking I/O, f_recv == NULL, f_recv_timout != NULL 1112 * 1113 * \note For DTLS, you need to provide either a non-NULL 1114 * f_recv_timeout callback, or a f_recv that doesn't block. 1115 * 1116 * \note See the documentations of \c mbedtls_ssl_sent_t, 1117 * \c mbedtls_ssl_recv_t and \c mbedtls_ssl_recv_timeout_t for 1118 * the conventions those callbacks must follow. 1119 * 1120 * \note On some platforms, net_sockets.c provides 1121 * \c mbedtls_net_send(), \c mbedtls_net_recv() and 1122 * \c mbedtls_net_recv_timeout() that are suitable to be used 1123 * here. 1124 */ 1125 void mbedtls_ssl_set_bio( mbedtls_ssl_context *ssl, 1126 void *p_bio, 1127 mbedtls_ssl_send_t *f_send, 1128 mbedtls_ssl_recv_t *f_recv, 1129 mbedtls_ssl_recv_timeout_t *f_recv_timeout ); 1130 1131 /** 1132 * \brief Set the timeout period for mbedtls_ssl_read() 1133 * (Default: no timeout.) 1134 * 1135 * \param conf SSL configuration context 1136 * \param timeout Timeout value in milliseconds. 1137 * Use 0 for no timeout (default). 1138 * 1139 * \note With blocking I/O, this will only work if a non-NULL 1140 * \c f_recv_timeout was set with \c mbedtls_ssl_set_bio(). 1141 * With non-blocking I/O, this will only work if timer 1142 * callbacks were set with \c mbedtls_ssl_set_timer_cb(). 1143 * 1144 * \note With non-blocking I/O, you may also skip this function 1145 * altogether and handle timeouts at the application layer. 1146 */ 1147 void mbedtls_ssl_conf_read_timeout( mbedtls_ssl_config *conf, uint32_t timeout ); 1148 1149 /** 1150 * \brief Set the timer callbacks (Mandatory for DTLS.) 1151 * 1152 * \param ssl SSL context 1153 * \param p_timer parameter (context) shared by timer callbacks 1154 * \param f_set_timer set timer callback 1155 * \param f_get_timer get timer callback. Must return: 1156 * 1157 * \note See the documentation of \c mbedtls_ssl_set_timer_t and 1158 * \c mbedtls_ssl_get_timer_t for the conventions this pair of 1159 * callbacks must follow. 1160 * 1161 * \note On some platforms, timing.c provides 1162 * \c mbedtls_timing_set_delay() and 1163 * \c mbedtls_timing_get_delay() that are suitable for using 1164 * here, except if using an event-driven style. 1165 * 1166 * \note See also the "DTLS tutorial" article in our knowledge base. 1167 * https://tls.mbed.org/kb/how-to/dtls-tutorial 1168 */ 1169 void mbedtls_ssl_set_timer_cb( mbedtls_ssl_context *ssl, 1170 void *p_timer, 1171 mbedtls_ssl_set_timer_t *f_set_timer, 1172 mbedtls_ssl_get_timer_t *f_get_timer ); 1173 1174 /** 1175 * \brief Callback type: generate and write session ticket 1176 * 1177 * \note This describes what a callback implementation should do. 1178 * This callback should generate an encrypted and 1179 * authenticated ticket for the session and write it to the 1180 * output buffer. Here, ticket means the opaque ticket part 1181 * of the NewSessionTicket structure of RFC 5077. 1182 * 1183 * \param p_ticket Context for the callback 1184 * \param session SSL session to be written in the ticket 1185 * \param start Start of the output buffer 1186 * \param end End of the output buffer 1187 * \param tlen On exit, holds the length written 1188 * \param lifetime On exit, holds the lifetime of the ticket in seconds 1189 * 1190 * \return 0 if successful, or 1191 * a specific MBEDTLS_ERR_XXX code. 1192 */ 1193 typedef int mbedtls_ssl_ticket_write_t( void *p_ticket, 1194 const mbedtls_ssl_session *session, 1195 unsigned char *start, 1196 const unsigned char *end, 1197 size_t *tlen, 1198 uint32_t *lifetime ); 1199 1200 #if defined(MBEDTLS_SSL_EXPORT_KEYS) 1201 /** 1202 * \brief Callback type: Export key block and master secret 1203 * 1204 * \note This is required for certain uses of TLS, e.g. EAP-TLS 1205 * (RFC 5216) and Thread. The key pointers are ephemeral and 1206 * therefore must not be stored. The master secret and keys 1207 * should not be used directly except as an input to a key 1208 * derivation function. 1209 * 1210 * \param p_expkey Context for the callback 1211 * \param ms Pointer to master secret (fixed length: 48 bytes) 1212 * \param kb Pointer to key block, see RFC 5246 section 6.3 1213 * (variable length: 2 * maclen + 2 * keylen + 2 * ivlen). 1214 * \param maclen MAC length 1215 * \param keylen Key length 1216 * \param ivlen IV length 1217 * 1218 * \return 0 if successful, or 1219 * a specific MBEDTLS_ERR_XXX code. 1220 */ 1221 typedef int mbedtls_ssl_export_keys_t( void *p_expkey, 1222 const unsigned char *ms, 1223 const unsigned char *kb, 1224 size_t maclen, 1225 size_t keylen, 1226 size_t ivlen ); 1227 #endif /* MBEDTLS_SSL_EXPORT_KEYS */ 1228 1229 /** 1230 * \brief Callback type: parse and load session ticket 1231 * 1232 * \note This describes what a callback implementation should do. 1233 * This callback should parse a session ticket as generated 1234 * by the corresponding mbedtls_ssl_ticket_write_t function, 1235 * and, if the ticket is authentic and valid, load the 1236 * session. 1237 * 1238 * \note The implementation is allowed to modify the first len 1239 * bytes of the input buffer, eg to use it as a temporary 1240 * area for the decrypted ticket contents. 1241 * 1242 * \param p_ticket Context for the callback 1243 * \param session SSL session to be loaded 1244 * \param buf Start of the buffer containing the ticket 1245 * \param len Length of the ticket. 1246 * 1247 * \return 0 if successful, or 1248 * MBEDTLS_ERR_SSL_INVALID_MAC if not authentic, or 1249 * MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED if expired, or 1250 * any other non-zero code for other failures. 1251 */ 1252 typedef int mbedtls_ssl_ticket_parse_t( void *p_ticket, 1253 mbedtls_ssl_session *session, 1254 unsigned char *buf, 1255 size_t len ); 1256 1257 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C) 1258 /** 1259 * \brief Configure SSL session ticket callbacks (server only). 1260 * (Default: none.) 1261 * 1262 * \note On server, session tickets are enabled by providing 1263 * non-NULL callbacks. 1264 * 1265 * \note On client, use \c mbedtls_ssl_conf_session_tickets(). 1266 * 1267 * \param conf SSL configuration context 1268 * \param f_ticket_write Callback for writing a ticket 1269 * \param f_ticket_parse Callback for parsing a ticket 1270 * \param p_ticket Context shared by the two callbacks 1271 */ 1272 void mbedtls_ssl_conf_session_tickets_cb( mbedtls_ssl_config *conf, 1273 mbedtls_ssl_ticket_write_t *f_ticket_write, 1274 mbedtls_ssl_ticket_parse_t *f_ticket_parse, 1275 void *p_ticket ); 1276 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */ 1277 1278 #if defined(MBEDTLS_SSL_EXPORT_KEYS) 1279 /** 1280 * \brief Configure key export callback. 1281 * (Default: none.) 1282 * 1283 * \note See \c mbedtls_ssl_export_keys_t. 1284 * 1285 * \param conf SSL configuration context 1286 * \param f_export_keys Callback for exporting keys 1287 * \param p_export_keys Context for the callback 1288 */ 1289 void mbedtls_ssl_conf_export_keys_cb( mbedtls_ssl_config *conf, 1290 mbedtls_ssl_export_keys_t *f_export_keys, 1291 void *p_export_keys ); 1292 #endif /* MBEDTLS_SSL_EXPORT_KEYS */ 1293 1294 /** 1295 * \brief Callback type: generate a cookie 1296 * 1297 * \param ctx Context for the callback 1298 * \param p Buffer to write to, 1299 * must be updated to point right after the cookie 1300 * \param end Pointer to one past the end of the output buffer 1301 * \param info Client ID info that was passed to 1302 * \c mbedtls_ssl_set_client_transport_id() 1303 * \param ilen Length of info in bytes 1304 * 1305 * \return The callback must return 0 on success, 1306 * or a negative error code. 1307 */ 1308 typedef int mbedtls_ssl_cookie_write_t( void *ctx, 1309 unsigned char **p, unsigned char *end, 1310 const unsigned char *info, size_t ilen ); 1311 1312 /** 1313 * \brief Callback type: verify a cookie 1314 * 1315 * \param ctx Context for the callback 1316 * \param cookie Cookie to verify 1317 * \param clen Length of cookie 1318 * \param info Client ID info that was passed to 1319 * \c mbedtls_ssl_set_client_transport_id() 1320 * \param ilen Length of info in bytes 1321 * 1322 * \return The callback must return 0 if cookie is valid, 1323 * or a negative error code. 1324 */ 1325 typedef int mbedtls_ssl_cookie_check_t( void *ctx, 1326 const unsigned char *cookie, size_t clen, 1327 const unsigned char *info, size_t ilen ); 1328 1329 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) 1330 /** 1331 * \brief Register callbacks for DTLS cookies 1332 * (Server only. DTLS only.) 1333 * 1334 * Default: dummy callbacks that fail, in order to force you to 1335 * register working callbacks (and initialize their context). 1336 * 1337 * To disable HelloVerifyRequest, register NULL callbacks. 1338 * 1339 * \warning Disabling hello verification allows your server to be used 1340 * for amplification in DoS attacks against other hosts. 1341 * Only disable if you known this can't happen in your 1342 * particular environment. 1343 * 1344 * \note See comments on \c mbedtls_ssl_handshake() about handling 1345 * the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected 1346 * on the first handshake attempt when this is enabled. 1347 * 1348 * \note This is also necessary to handle client reconnection from 1349 * the same port as described in RFC 6347 section 4.2.8 (only 1350 * the variant with cookies is supported currently). See 1351 * comments on \c mbedtls_ssl_read() for details. 1352 * 1353 * \param conf SSL configuration 1354 * \param f_cookie_write Cookie write callback 1355 * \param f_cookie_check Cookie check callback 1356 * \param p_cookie Context for both callbacks 1357 */ 1358 void mbedtls_ssl_conf_dtls_cookies( mbedtls_ssl_config *conf, 1359 mbedtls_ssl_cookie_write_t *f_cookie_write, 1360 mbedtls_ssl_cookie_check_t *f_cookie_check, 1361 void *p_cookie ); 1362 1363 /** 1364 * \brief Set client's transport-level identification info. 1365 * (Server only. DTLS only.) 1366 * 1367 * This is usually the IP address (and port), but could be 1368 * anything identify the client depending on the underlying 1369 * network stack. Used for HelloVerifyRequest with DTLS. 1370 * This is *not* used to route the actual packets. 1371 * 1372 * \param ssl SSL context 1373 * \param info Transport-level info identifying the client (eg IP + port) 1374 * \param ilen Length of info in bytes 1375 * 1376 * \note An internal copy is made, so the info buffer can be reused. 1377 * 1378 * \return 0 on success, 1379 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client, 1380 * MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory. 1381 */ 1382 int mbedtls_ssl_set_client_transport_id( mbedtls_ssl_context *ssl, 1383 const unsigned char *info, 1384 size_t ilen ); 1385 1386 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */ 1387 1388 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) 1389 /** 1390 * \brief Enable or disable anti-replay protection for DTLS. 1391 * (DTLS only, no effect on TLS.) 1392 * Default: enabled. 1393 * 1394 * \param conf SSL configuration 1395 * \param mode MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED. 1396 * 1397 * \warning Disabling this is a security risk unless the application 1398 * protocol handles duplicated packets in a safe way. You 1399 * should not disable this without careful consideration. 1400 * However, if your application already detects duplicated 1401 * packets and needs information about them to adjust its 1402 * transmission strategy, then you'll want to disable this. 1403 */ 1404 void mbedtls_ssl_conf_dtls_anti_replay( mbedtls_ssl_config *conf, char mode ); 1405 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */ 1406 1407 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT) 1408 /** 1409 * \brief Set a limit on the number of records with a bad MAC 1410 * before terminating the connection. 1411 * (DTLS only, no effect on TLS.) 1412 * Default: 0 (disabled). 1413 * 1414 * \param conf SSL configuration 1415 * \param limit Limit, or 0 to disable. 1416 * 1417 * \note If the limit is N, then the connection is terminated when 1418 * the Nth non-authentic record is seen. 1419 * 1420 * \note Records with an invalid header are not counted, only the 1421 * ones going through the authentication-decryption phase. 1422 * 1423 * \note This is a security trade-off related to the fact that it's 1424 * often relatively easy for an active attacker ot inject UDP 1425 * datagrams. On one hand, setting a low limit here makes it 1426 * easier for such an attacker to forcibly terminated a 1427 * connection. On the other hand, a high limit or no limit 1428 * might make us waste resources checking authentication on 1429 * many bogus packets. 1430 */ 1431 void mbedtls_ssl_conf_dtls_badmac_limit( mbedtls_ssl_config *conf, unsigned limit ); 1432 #endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */ 1433 1434 #if defined(MBEDTLS_SSL_PROTO_DTLS) 1435 /** 1436 * \brief Set retransmit timeout values for the DTLS handshake. 1437 * (DTLS only, no effect on TLS.) 1438 * 1439 * \param conf SSL configuration 1440 * \param min Initial timeout value in milliseconds. 1441 * Default: 1000 (1 second). 1442 * \param max Maximum timeout value in milliseconds. 1443 * Default: 60000 (60 seconds). 1444 * 1445 * \note Default values are from RFC 6347 section 4.2.4.1. 1446 * 1447 * \note The 'min' value should typically be slightly above the 1448 * expected round-trip time to your peer, plus whatever time 1449 * it takes for the peer to process the message. For example, 1450 * if your RTT is about 600ms and you peer needs up to 1s to 1451 * do the cryptographic operations in the handshake, then you 1452 * should set 'min' slightly above 1600. Lower values of 'min' 1453 * might cause spurious resends which waste network resources, 1454 * while larger value of 'min' will increase overall latency 1455 * on unreliable network links. 1456 * 1457 * \note The more unreliable your network connection is, the larger 1458 * your max / min ratio needs to be in order to achieve 1459 * reliable handshakes. 1460 * 1461 * \note Messages are retransmitted up to log2(ceil(max/min)) times. 1462 * For example, if min = 1s and max = 5s, the retransmit plan 1463 * goes: send ... 1s -> resend ... 2s -> resend ... 4s -> 1464 * resend ... 5s -> give up and return a timeout error. 1465 */ 1466 void mbedtls_ssl_conf_handshake_timeout( mbedtls_ssl_config *conf, uint32_t min, uint32_t max ); 1467 #endif /* MBEDTLS_SSL_PROTO_DTLS */ 1468 1469 #if defined(MBEDTLS_SSL_SRV_C) 1470 /** 1471 * \brief Set the session cache callbacks (server-side only) 1472 * If not set, no session resuming is done (except if session 1473 * tickets are enabled too). 1474 * 1475 * The session cache has the responsibility to check for stale 1476 * entries based on timeout. See RFC 5246 for recommendations. 1477 * 1478 * Warning: session.peer_cert is cleared by the SSL/TLS layer on 1479 * connection shutdown, so do not cache the pointer! Either set 1480 * it to NULL or make a full copy of the certificate. 1481 * 1482 * The get callback is called once during the initial handshake 1483 * to enable session resuming. The get function has the 1484 * following parameters: (void *parameter, mbedtls_ssl_session *session) 1485 * If a valid entry is found, it should fill the master of 1486 * the session object with the cached values and return 0, 1487 * return 1 otherwise. Optionally peer_cert can be set as well 1488 * if it is properly present in cache entry. 1489 * 1490 * The set callback is called once during the initial handshake 1491 * to enable session resuming after the entire handshake has 1492 * been finished. The set function has the following parameters: 1493 * (void *parameter, const mbedtls_ssl_session *session). The function 1494 * should create a cache entry for future retrieval based on 1495 * the data in the session structure and should keep in mind 1496 * that the mbedtls_ssl_session object presented (and all its referenced 1497 * data) is cleared by the SSL/TLS layer when the connection is 1498 * terminated. It is recommended to add metadata to determine if 1499 * an entry is still valid in the future. Return 0 if 1500 * successfully cached, return 1 otherwise. 1501 * 1502 * \param conf SSL configuration 1503 * \param p_cache parmater (context) for both callbacks 1504 * \param f_get_cache session get callback 1505 * \param f_set_cache session set callback 1506 */ 1507 void mbedtls_ssl_conf_session_cache( mbedtls_ssl_config *conf, 1508 void *p_cache, 1509 int (*f_get_cache)(void *, mbedtls_ssl_session *), 1510 int (*f_set_cache)(void *, const mbedtls_ssl_session *) ); 1511 #endif /* MBEDTLS_SSL_SRV_C */ 1512 1513 #if defined(MBEDTLS_SSL_CLI_C) 1514 /** 1515 * \brief Request resumption of session (client-side only) 1516 * Session data is copied from presented session structure. 1517 * 1518 * \param ssl SSL context 1519 * \param session session context 1520 * 1521 * \return 0 if successful, 1522 * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed, 1523 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or 1524 * arguments are otherwise invalid 1525 * 1526 * \sa mbedtls_ssl_get_session() 1527 */ 1528 int mbedtls_ssl_set_session( mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session ); 1529 #endif /* MBEDTLS_SSL_CLI_C */ 1530 1531 /** 1532 * \brief Set the list of allowed ciphersuites and the preference 1533 * order. First in the list has the highest preference. 1534 * (Overrides all version-specific lists) 1535 * 1536 * The ciphersuites array is not copied, and must remain 1537 * valid for the lifetime of the ssl_config. 1538 * 1539 * Note: The server uses its own preferences 1540 * over the preference of the client unless 1541 * MBEDTLS_SSL_SRV_RESPECT_CLIENT_PREFERENCE is defined! 1542 * 1543 * \param conf SSL configuration 1544 * \param ciphersuites 0-terminated list of allowed ciphersuites 1545 */ 1546 void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf, 1547 const int *ciphersuites ); 1548 1549 /** 1550 * \brief Set the list of allowed ciphersuites and the 1551 * preference order for a specific version of the protocol. 1552 * (Only useful on the server side) 1553 * 1554 * The ciphersuites array is not copied, and must remain 1555 * valid for the lifetime of the ssl_config. 1556 * 1557 * \param conf SSL configuration 1558 * \param ciphersuites 0-terminated list of allowed ciphersuites 1559 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 1560 * supported) 1561 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0, 1562 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2, 1563 * MBEDTLS_SSL_MINOR_VERSION_3 supported) 1564 * 1565 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 1566 * and MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2 1567 */ 1568 void mbedtls_ssl_conf_ciphersuites_for_version( mbedtls_ssl_config *conf, 1569 const int *ciphersuites, 1570 int major, int minor ); 1571 1572 #if defined(MBEDTLS_X509_CRT_PARSE_C) 1573 /** 1574 * \brief Set the X.509 security profile used for verification 1575 * 1576 * \note The restrictions are enforced for all certificates in the 1577 * chain. However, signatures in the handshake are not covered 1578 * by this setting but by \b mbedtls_ssl_conf_sig_hashes(). 1579 * 1580 * \param conf SSL configuration 1581 * \param profile Profile to use 1582 */ 1583 void mbedtls_ssl_conf_cert_profile( mbedtls_ssl_config *conf, 1584 const mbedtls_x509_crt_profile *profile ); 1585 1586 /** 1587 * \brief Set the data required to verify peer certificate 1588 * 1589 * \note See \c mbedtls_x509_crt_verify() for notes regarding the 1590 * parameters ca_chain (maps to trust_ca for that function) 1591 * and ca_crl. 1592 * 1593 * \param conf SSL configuration 1594 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs) 1595 * \param ca_crl trusted CA CRLs 1596 */ 1597 void mbedtls_ssl_conf_ca_chain( mbedtls_ssl_config *conf, 1598 mbedtls_x509_crt *ca_chain, 1599 mbedtls_x509_crl *ca_crl ); 1600 1601 /** 1602 * \brief Set own certificate chain and private key 1603 * 1604 * \note own_cert should contain in order from the bottom up your 1605 * certificate chain. The top certificate (self-signed) 1606 * can be omitted. 1607 * 1608 * \note On server, this function can be called multiple times to 1609 * provision more than one cert/key pair (eg one ECDSA, one 1610 * RSA with SHA-256, one RSA with SHA-1). An adequate 1611 * certificate will be selected according to the client's 1612 * advertised capabilities. In case multiple certificates are 1613 * adequate, preference is given to the one set by the first 1614 * call to this function, then second, etc. 1615 * 1616 * \note On client, only the first call has any effect. That is, 1617 * only one client certificate can be provisioned. The 1618 * server's preferences in its CertficateRequest message will 1619 * be ignored and our only cert will be sent regardless of 1620 * whether it matches those preferences - the server can then 1621 * decide what it wants to do with it. 1622 * 1623 * \note The provided \p pk_key needs to match the public key in the 1624 * first certificate in \p own_cert, or all handshakes using 1625 * that certificate will fail. It is your responsibility 1626 * to ensure that; this function will not perform any check. 1627 * You may use mbedtls_pk_check_pair() in order to perform 1628 * this check yourself, but be aware that this function can 1629 * be computationally expensive on some key types. 1630 * 1631 * \param conf SSL configuration 1632 * \param own_cert own public certificate chain 1633 * \param pk_key own private key 1634 * 1635 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED 1636 */ 1637 int mbedtls_ssl_conf_own_cert( mbedtls_ssl_config *conf, 1638 mbedtls_x509_crt *own_cert, 1639 mbedtls_pk_context *pk_key ); 1640 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 1641 1642 #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) 1643 /** 1644 * \brief Set the Pre Shared Key (PSK) and the expected identity name 1645 * 1646 * \note This is mainly useful for clients. Servers will usually 1647 * want to use \c mbedtls_ssl_conf_psk_cb() instead. 1648 * 1649 * \note Currently clients can only register one pre-shared key. 1650 * In other words, the servers' identity hint is ignored. 1651 * Support for setting multiple PSKs on clients and selecting 1652 * one based on the identity hint is not a planned feature but 1653 * feedback is welcomed. 1654 * 1655 * \param conf SSL configuration 1656 * \param psk pointer to the pre-shared key 1657 * \param psk_len pre-shared key length 1658 * \param psk_identity pointer to the pre-shared key identity 1659 * \param psk_identity_len identity key length 1660 * 1661 * \return 0 if successful or MBEDTLS_ERR_SSL_ALLOC_FAILED 1662 */ 1663 int mbedtls_ssl_conf_psk( mbedtls_ssl_config *conf, 1664 const unsigned char *psk, size_t psk_len, 1665 const unsigned char *psk_identity, size_t psk_identity_len ); 1666 1667 1668 /** 1669 * \brief Set the Pre Shared Key (PSK) for the current handshake 1670 * 1671 * \note This should only be called inside the PSK callback, 1672 * ie the function passed to \c mbedtls_ssl_conf_psk_cb(). 1673 * 1674 * \param ssl SSL context 1675 * \param psk pointer to the pre-shared key 1676 * \param psk_len pre-shared key length 1677 * 1678 * \return 0 if successful or MBEDTLS_ERR_SSL_ALLOC_FAILED 1679 */ 1680 int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl, 1681 const unsigned char *psk, size_t psk_len ); 1682 1683 /** 1684 * \brief Set the PSK callback (server-side only). 1685 * 1686 * If set, the PSK callback is called for each 1687 * handshake where a PSK ciphersuite was negotiated. 1688 * The caller provides the identity received and wants to 1689 * receive the actual PSK data and length. 1690 * 1691 * The callback has the following parameters: (void *parameter, 1692 * mbedtls_ssl_context *ssl, const unsigned char *psk_identity, 1693 * size_t identity_len) 1694 * If a valid PSK identity is found, the callback should use 1695 * \c mbedtls_ssl_set_hs_psk() on the ssl context to set the 1696 * correct PSK and return 0. 1697 * Any other return value will result in a denied PSK identity. 1698 * 1699 * \note If you set a PSK callback using this function, then you 1700 * don't need to set a PSK key and identity using 1701 * \c mbedtls_ssl_conf_psk(). 1702 * 1703 * \param conf SSL configuration 1704 * \param f_psk PSK identity function 1705 * \param p_psk PSK identity parameter 1706 */ 1707 void mbedtls_ssl_conf_psk_cb( mbedtls_ssl_config *conf, 1708 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, 1709 size_t), 1710 void *p_psk ); 1711 #endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */ 1712 1713 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C) 1714 1715 #if !defined(MBEDTLS_DEPRECATED_REMOVED) 1716 1717 #if defined(MBEDTLS_DEPRECATED_WARNING) 1718 #define MBEDTLS_DEPRECATED __attribute__((deprecated)) 1719 #else 1720 #define MBEDTLS_DEPRECATED 1721 #endif 1722 1723 /** 1724 * \brief Set the Diffie-Hellman public P and G values, 1725 * read as hexadecimal strings (server-side only) 1726 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]) 1727 * 1728 * \param conf SSL configuration 1729 * \param dhm_P Diffie-Hellman-Merkle modulus 1730 * \param dhm_G Diffie-Hellman-Merkle generator 1731 * 1732 * \deprecated Superseded by \c mbedtls_ssl_conf_dh_param_bin. 1733 * 1734 * \return 0 if successful 1735 */ 1736 MBEDTLS_DEPRECATED int mbedtls_ssl_conf_dh_param( mbedtls_ssl_config *conf, 1737 const char *dhm_P, 1738 const char *dhm_G ); 1739 1740 #endif /* MBEDTLS_DEPRECATED_REMOVED */ 1741 1742 /** 1743 * \brief Set the Diffie-Hellman public P and G values 1744 * from big-endian binary presentations. 1745 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN) 1746 * 1747 * \param conf SSL configuration 1748 * \param dhm_P Diffie-Hellman-Merkle modulus in big-endian binary form 1749 * \param P_len Length of DHM modulus 1750 * \param dhm_G Diffie-Hellman-Merkle generator in big-endian binary form 1751 * \param G_len Length of DHM generator 1752 * 1753 * \return 0 if successful 1754 */ 1755 int mbedtls_ssl_conf_dh_param_bin( mbedtls_ssl_config *conf, 1756 const unsigned char *dhm_P, size_t P_len, 1757 const unsigned char *dhm_G, size_t G_len ); 1758 1759 /** 1760 * \brief Set the Diffie-Hellman public P and G values, 1761 * read from existing context (server-side only) 1762 * 1763 * \param conf SSL configuration 1764 * \param dhm_ctx Diffie-Hellman-Merkle context 1765 * 1766 * \return 0 if successful 1767 */ 1768 int mbedtls_ssl_conf_dh_param_ctx( mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx ); 1769 #endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */ 1770 1771 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C) 1772 /** 1773 * \brief Set the minimum length for Diffie-Hellman parameters. 1774 * (Client-side only.) 1775 * (Default: 1024 bits.) 1776 * 1777 * \param conf SSL configuration 1778 * \param bitlen Minimum bit length of the DHM prime 1779 */ 1780 void mbedtls_ssl_conf_dhm_min_bitlen( mbedtls_ssl_config *conf, 1781 unsigned int bitlen ); 1782 #endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */ 1783 1784 #if defined(MBEDTLS_ECP_C) 1785 /** 1786 * \brief Set the allowed curves in order of preference. 1787 * (Default: all defined curves.) 1788 * 1789 * On server: this only affects selection of the ECDHE curve; 1790 * the curves used for ECDH and ECDSA are determined by the 1791 * list of available certificates instead. 1792 * 1793 * On client: this affects the list of curves offered for any 1794 * use. The server can override our preference order. 1795 * 1796 * Both sides: limits the set of curves accepted for use in 1797 * ECDHE and in the peer's end-entity certificate. 1798 * 1799 * \note This has no influence on which curves are allowed inside the 1800 * certificate chains, see \c mbedtls_ssl_conf_cert_profile() 1801 * for that. For the end-entity certificate however, the key 1802 * will be accepted only if it is allowed both by this list 1803 * and by the cert profile. 1804 * 1805 * \note This list should be ordered by decreasing preference 1806 * (preferred curve first). 1807 * 1808 * \param conf SSL configuration 1809 * \param curves Ordered list of allowed curves, 1810 * terminated by MBEDTLS_ECP_DP_NONE. 1811 */ 1812 void mbedtls_ssl_conf_curves( mbedtls_ssl_config *conf, 1813 const mbedtls_ecp_group_id *curves ); 1814 #endif /* MBEDTLS_ECP_C */ 1815 1816 #if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) 1817 /** 1818 * \brief Set the allowed hashes for signatures during the handshake. 1819 * (Default: all available hashes except MD5.) 1820 * 1821 * \note This only affects which hashes are offered and can be used 1822 * for signatures during the handshake. Hashes for message 1823 * authentication and the TLS PRF are controlled by the 1824 * ciphersuite, see \c mbedtls_ssl_conf_ciphersuites(). Hashes 1825 * used for certificate signature are controlled by the 1826 * verification profile, see \c mbedtls_ssl_conf_cert_profile(). 1827 * 1828 * \note This list should be ordered by decreasing preference 1829 * (preferred hash first). 1830 * 1831 * \param conf SSL configuration 1832 * \param hashes Ordered list of allowed signature hashes, 1833 * terminated by \c MBEDTLS_MD_NONE. 1834 */ 1835 void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf, 1836 const int *hashes ); 1837 #endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */ 1838 1839 #if defined(MBEDTLS_X509_CRT_PARSE_C) 1840 /** 1841 * \brief Set or reset the hostname to check against the received 1842 * server certificate. It sets the ServerName TLS extension, 1843 * too, if that extension is enabled. (client-side only) 1844 * 1845 * \param ssl SSL context 1846 * \param hostname the server hostname, may be NULL to clear hostname 1847 * 1848 * \note Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN. 1849 * 1850 * \return 0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on 1851 * allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on 1852 * too long input hostname. 1853 * 1854 * Hostname set to the one provided on success (cleared 1855 * when NULL). On allocation failure hostname is cleared. 1856 * On too long input failure, old hostname is unchanged. 1857 */ 1858 int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname ); 1859 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 1860 1861 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) 1862 /** 1863 * \brief Set own certificate and key for the current handshake 1864 * 1865 * \note Same as \c mbedtls_ssl_conf_own_cert() but for use within 1866 * the SNI callback. 1867 * 1868 * \param ssl SSL context 1869 * \param own_cert own public certificate chain 1870 * \param pk_key own private key 1871 * 1872 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED 1873 */ 1874 int mbedtls_ssl_set_hs_own_cert( mbedtls_ssl_context *ssl, 1875 mbedtls_x509_crt *own_cert, 1876 mbedtls_pk_context *pk_key ); 1877 1878 /** 1879 * \brief Set the data required to verify peer certificate for the 1880 * current handshake 1881 * 1882 * \note Same as \c mbedtls_ssl_conf_ca_chain() but for use within 1883 * the SNI callback. 1884 * 1885 * \param ssl SSL context 1886 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs) 1887 * \param ca_crl trusted CA CRLs 1888 */ 1889 void mbedtls_ssl_set_hs_ca_chain( mbedtls_ssl_context *ssl, 1890 mbedtls_x509_crt *ca_chain, 1891 mbedtls_x509_crl *ca_crl ); 1892 1893 /** 1894 * \brief Set authmode for the current handshake. 1895 * 1896 * \note Same as \c mbedtls_ssl_conf_authmode() but for use within 1897 * the SNI callback. 1898 * 1899 * \param ssl SSL context 1900 * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or 1901 * MBEDTLS_SSL_VERIFY_REQUIRED 1902 */ 1903 void mbedtls_ssl_set_hs_authmode( mbedtls_ssl_context *ssl, 1904 int authmode ); 1905 1906 /** 1907 * \brief Set server side ServerName TLS extension callback 1908 * (optional, server-side only). 1909 * 1910 * If set, the ServerName callback is called whenever the 1911 * server receives a ServerName TLS extension from the client 1912 * during a handshake. The ServerName callback has the 1913 * following parameters: (void *parameter, mbedtls_ssl_context *ssl, 1914 * const unsigned char *hostname, size_t len). If a suitable 1915 * certificate is found, the callback must set the 1916 * certificate(s) and key(s) to use with \c 1917 * mbedtls_ssl_set_hs_own_cert() (can be called repeatedly), 1918 * and may optionally adjust the CA and associated CRL with \c 1919 * mbedtls_ssl_set_hs_ca_chain() as well as the client 1920 * authentication mode with \c mbedtls_ssl_set_hs_authmode(), 1921 * then must return 0. If no matching name is found, the 1922 * callback must either set a default cert, or 1923 * return non-zero to abort the handshake at this point. 1924 * 1925 * \param conf SSL configuration 1926 * \param f_sni verification function 1927 * \param p_sni verification parameter 1928 */ 1929 void mbedtls_ssl_conf_sni( mbedtls_ssl_config *conf, 1930 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, 1931 size_t), 1932 void *p_sni ); 1933 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */ 1934 1935 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) 1936 /** 1937 * \brief Set the EC J-PAKE password for current handshake. 1938 * 1939 * \note An internal copy is made, and destroyed as soon as the 1940 * handshake is completed, or when the SSL context is reset or 1941 * freed. 1942 * 1943 * \note The SSL context needs to be already set up. The right place 1944 * to call this function is between \c mbedtls_ssl_setup() or 1945 * \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake(). 1946 * 1947 * \param ssl SSL context 1948 * \param pw EC J-PAKE password (pre-shared secret) 1949 * \param pw_len length of pw in bytes 1950 * 1951 * \return 0 on success, or a negative error code. 1952 */ 1953 int mbedtls_ssl_set_hs_ecjpake_password( mbedtls_ssl_context *ssl, 1954 const unsigned char *pw, 1955 size_t pw_len ); 1956 #endif /*MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ 1957 1958 #if defined(MBEDTLS_SSL_ALPN) 1959 /** 1960 * \brief Set the supported Application Layer Protocols. 1961 * 1962 * \param conf SSL configuration 1963 * \param protos Pointer to a NULL-terminated list of supported protocols, 1964 * in decreasing preference order. The pointer to the list is 1965 * recorded by the library for later reference as required, so 1966 * the lifetime of the table must be atleast as long as the 1967 * lifetime of the SSL configuration structure. 1968 * 1969 * \return 0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA. 1970 */ 1971 int mbedtls_ssl_conf_alpn_protocols( mbedtls_ssl_config *conf, const char **protos ); 1972 1973 /** 1974 * \brief Get the name of the negotiated Application Layer Protocol. 1975 * This function should be called after the handshake is 1976 * completed. 1977 * 1978 * \param ssl SSL context 1979 * 1980 * \return Protcol name, or NULL if no protocol was negotiated. 1981 */ 1982 const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl ); 1983 #endif /* MBEDTLS_SSL_ALPN */ 1984 1985 /** 1986 * \brief Set the maximum supported version sent from the client side 1987 * and/or accepted at the server side 1988 * (Default: MBEDTLS_SSL_MAX_MAJOR_VERSION, MBEDTLS_SSL_MAX_MINOR_VERSION) 1989 * 1990 * \note This ignores ciphersuites from higher versions. 1991 * 1992 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and 1993 * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2 1994 * 1995 * \param conf SSL configuration 1996 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported) 1997 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0, 1998 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2, 1999 * MBEDTLS_SSL_MINOR_VERSION_3 supported) 2000 */ 2001 void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor ); 2002 2003 /** 2004 * \brief Set the minimum accepted SSL/TLS protocol version 2005 * (Default: TLS 1.0) 2006 * 2007 * \note Input outside of the SSL_MAX_XXXXX_VERSION and 2008 * SSL_MIN_XXXXX_VERSION range is ignored. 2009 * 2010 * \note MBEDTLS_SSL_MINOR_VERSION_0 (SSL v3) should be avoided. 2011 * 2012 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and 2013 * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2 2014 * 2015 * \param conf SSL configuration 2016 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported) 2017 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0, 2018 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2, 2019 * MBEDTLS_SSL_MINOR_VERSION_3 supported) 2020 */ 2021 void mbedtls_ssl_conf_min_version( mbedtls_ssl_config *conf, int major, int minor ); 2022 2023 #if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C) 2024 /** 2025 * \brief Set the fallback flag (client-side only). 2026 * (Default: MBEDTLS_SSL_IS_NOT_FALLBACK). 2027 * 2028 * \note Set to MBEDTLS_SSL_IS_FALLBACK when preparing a fallback 2029 * connection, that is a connection with max_version set to a 2030 * lower value than the value you're willing to use. Such 2031 * fallback connections are not recommended but are sometimes 2032 * necessary to interoperate with buggy (version-intolerant) 2033 * servers. 2034 * 2035 * \warning You should NOT set this to MBEDTLS_SSL_IS_FALLBACK for 2036 * non-fallback connections! This would appear to work for a 2037 * while, then cause failures when the server is upgraded to 2038 * support a newer TLS version. 2039 * 2040 * \param conf SSL configuration 2041 * \param fallback MBEDTLS_SSL_IS_NOT_FALLBACK or MBEDTLS_SSL_IS_FALLBACK 2042 */ 2043 void mbedtls_ssl_conf_fallback( mbedtls_ssl_config *conf, char fallback ); 2044 #endif /* MBEDTLS_SSL_FALLBACK_SCSV && MBEDTLS_SSL_CLI_C */ 2045 2046 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) 2047 /** 2048 * \brief Enable or disable Encrypt-then-MAC 2049 * (Default: MBEDTLS_SSL_ETM_ENABLED) 2050 * 2051 * \note This should always be enabled, it is a security 2052 * improvement, and should not cause any interoperability 2053 * issue (used only if the peer supports it too). 2054 * 2055 * \param conf SSL configuration 2056 * \param etm MBEDTLS_SSL_ETM_ENABLED or MBEDTLS_SSL_ETM_DISABLED 2057 */ 2058 void mbedtls_ssl_conf_encrypt_then_mac( mbedtls_ssl_config *conf, char etm ); 2059 #endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */ 2060 2061 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) 2062 /** 2063 * \brief Enable or disable Extended Master Secret negotiation. 2064 * (Default: MBEDTLS_SSL_EXTENDED_MS_ENABLED) 2065 * 2066 * \note This should always be enabled, it is a security fix to the 2067 * protocol, and should not cause any interoperability issue 2068 * (used only if the peer supports it too). 2069 * 2070 * \param conf SSL configuration 2071 * \param ems MBEDTLS_SSL_EXTENDED_MS_ENABLED or MBEDTLS_SSL_EXTENDED_MS_DISABLED 2072 */ 2073 void mbedtls_ssl_conf_extended_master_secret( mbedtls_ssl_config *conf, char ems ); 2074 #endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */ 2075 2076 #if defined(MBEDTLS_ARC4_C) 2077 /** 2078 * \brief Disable or enable support for RC4 2079 * (Default: MBEDTLS_SSL_ARC4_DISABLED) 2080 * 2081 * \warning Use of RC4 in DTLS/TLS has been prohibited by RFC 7465 2082 * for security reasons. Use at your own risk. 2083 * 2084 * \note This function is deprecated and will likely be removed in 2085 * a future version of the library. 2086 * RC4 is disabled by default at compile time and needs to be 2087 * actively enabled for use with legacy systems. 2088 * 2089 * \param conf SSL configuration 2090 * \param arc4 MBEDTLS_SSL_ARC4_ENABLED or MBEDTLS_SSL_ARC4_DISABLED 2091 */ 2092 void mbedtls_ssl_conf_arc4_support( mbedtls_ssl_config *conf, char arc4 ); 2093 #endif /* MBEDTLS_ARC4_C */ 2094 2095 #if defined(MBEDTLS_SSL_SRV_C) 2096 /** 2097 * \brief Whether to send a list of acceptable CAs in 2098 * CertificateRequest messages. 2099 * (Default: do send) 2100 * 2101 * \param conf SSL configuration 2102 * \param cert_req_ca_list MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or 2103 * MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 2104 */ 2105 void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf, 2106 char cert_req_ca_list ); 2107 #endif /* MBEDTLS_SSL_SRV_C */ 2108 2109 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) 2110 /** 2111 * \brief Set the maximum fragment length to emit and/or negotiate. 2112 * (Typical: #MBEDTLS_SSL_MAX_CONTENT_LEN, by default that is 2113 * set to `2^14` bytes) 2114 * (Server: set maximum fragment length to emit, 2115 * usually negotiated by the client during handshake) 2116 * (Client: set maximum fragment length to emit *and* 2117 * negotiate with the server during handshake) 2118 * (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE) 2119 * 2120 * \note With TLS, this currently only affects ApplicationData (sent 2121 * with \c mbedtls_ssl_read()), not handshake messages. 2122 * With DTLS, this affects both ApplicationData and handshake. 2123 * 2124 * \note On the client side, the maximum fragment length extension 2125 * *will not* be used, unless the maximum fragment length has 2126 * been set via this function to a value different than 2127 * #MBEDTLS_SSL_MAX_FRAG_LEN_NONE. 2128 * 2129 * \note This sets the maximum length for a record's payload, 2130 * excluding record overhead that will be added to it, see 2131 * \c mbedtls_ssl_get_record_expansion(). 2132 * 2133 * \param conf SSL configuration 2134 * \param mfl_code Code for maximum fragment length (allowed values: 2135 * MBEDTLS_SSL_MAX_FRAG_LEN_512, MBEDTLS_SSL_MAX_FRAG_LEN_1024, 2136 * MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096) 2137 * 2138 * \return 0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA 2139 */ 2140 int mbedtls_ssl_conf_max_frag_len( mbedtls_ssl_config *conf, unsigned char mfl_code ); 2141 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ 2142 2143 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC) 2144 /** 2145 * \brief Activate negotiation of truncated HMAC 2146 * (Default: MBEDTLS_SSL_TRUNC_HMAC_DISABLED) 2147 * 2148 * \param conf SSL configuration 2149 * \param truncate Enable or disable (MBEDTLS_SSL_TRUNC_HMAC_ENABLED or 2150 * MBEDTLS_SSL_TRUNC_HMAC_DISABLED) 2151 */ 2152 void mbedtls_ssl_conf_truncated_hmac( mbedtls_ssl_config *conf, int truncate ); 2153 #endif /* MBEDTLS_SSL_TRUNCATED_HMAC */ 2154 2155 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING) 2156 /** 2157 * \brief Enable / Disable 1/n-1 record splitting 2158 * (Default: MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED) 2159 * 2160 * \note Only affects SSLv3 and TLS 1.0, not higher versions. 2161 * Does not affect non-CBC ciphersuites in any version. 2162 * 2163 * \param conf SSL configuration 2164 * \param split MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED or 2165 * MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED 2166 */ 2167 void mbedtls_ssl_conf_cbc_record_splitting( mbedtls_ssl_config *conf, char split ); 2168 #endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */ 2169 2170 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C) 2171 /** 2172 * \brief Enable / Disable session tickets (client only). 2173 * (Default: MBEDTLS_SSL_SESSION_TICKETS_ENABLED.) 2174 * 2175 * \note On server, use \c mbedtls_ssl_conf_session_tickets_cb(). 2176 * 2177 * \param conf SSL configuration 2178 * \param use_tickets Enable or disable (MBEDTLS_SSL_SESSION_TICKETS_ENABLED or 2179 * MBEDTLS_SSL_SESSION_TICKETS_DISABLED) 2180 */ 2181 void mbedtls_ssl_conf_session_tickets( mbedtls_ssl_config *conf, int use_tickets ); 2182 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */ 2183 2184 #if defined(MBEDTLS_SSL_RENEGOTIATION) 2185 /** 2186 * \brief Enable / Disable renegotiation support for connection when 2187 * initiated by peer 2188 * (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED) 2189 * 2190 * \warning It is recommended to always disable renegotation unless you 2191 * know you need it and you know what you're doing. In the 2192 * past, there have been several issues associated with 2193 * renegotiation or a poor understanding of its properties. 2194 * 2195 * \note Server-side, enabling renegotiation also makes the server 2196 * susceptible to a resource DoS by a malicious client. 2197 * 2198 * \param conf SSL configuration 2199 * \param renegotiation Enable or disable (MBEDTLS_SSL_RENEGOTIATION_ENABLED or 2200 * MBEDTLS_SSL_RENEGOTIATION_DISABLED) 2201 */ 2202 void mbedtls_ssl_conf_renegotiation( mbedtls_ssl_config *conf, int renegotiation ); 2203 #endif /* MBEDTLS_SSL_RENEGOTIATION */ 2204 2205 /** 2206 * \brief Prevent or allow legacy renegotiation. 2207 * (Default: MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION) 2208 * 2209 * MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION allows connections to 2210 * be established even if the peer does not support 2211 * secure renegotiation, but does not allow renegotiation 2212 * to take place if not secure. 2213 * (Interoperable and secure option) 2214 * 2215 * MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION allows renegotiations 2216 * with non-upgraded peers. Allowing legacy renegotiation 2217 * makes the connection vulnerable to specific man in the 2218 * middle attacks. (See RFC 5746) 2219 * (Most interoperable and least secure option) 2220 * 2221 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE breaks off connections 2222 * if peer does not support secure renegotiation. Results 2223 * in interoperability issues with non-upgraded peers 2224 * that do not support renegotiation altogether. 2225 * (Most secure option, interoperability issues) 2226 * 2227 * \param conf SSL configuration 2228 * \param allow_legacy Prevent or allow (SSL_NO_LEGACY_RENEGOTIATION, 2229 * SSL_ALLOW_LEGACY_RENEGOTIATION or 2230 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE) 2231 */ 2232 void mbedtls_ssl_conf_legacy_renegotiation( mbedtls_ssl_config *conf, int allow_legacy ); 2233 2234 #if defined(MBEDTLS_SSL_RENEGOTIATION) 2235 /** 2236 * \brief Enforce renegotiation requests. 2237 * (Default: enforced, max_records = 16) 2238 * 2239 * When we request a renegotiation, the peer can comply or 2240 * ignore the request. This function allows us to decide 2241 * whether to enforce our renegotiation requests by closing 2242 * the connection if the peer doesn't comply. 2243 * 2244 * However, records could already be in transit from the peer 2245 * when the request is emitted. In order to increase 2246 * reliability, we can accept a number of records before the 2247 * expected handshake records. 2248 * 2249 * The optimal value is highly dependent on the specific usage 2250 * scenario. 2251 * 2252 * \note With DTLS and server-initiated renegotiation, the 2253 * HelloRequest is retransmited every time mbedtls_ssl_read() times 2254 * out or receives Application Data, until: 2255 * - max_records records have beens seen, if it is >= 0, or 2256 * - the number of retransmits that would happen during an 2257 * actual handshake has been reached. 2258 * Please remember the request might be lost a few times 2259 * if you consider setting max_records to a really low value. 2260 * 2261 * \warning On client, the grace period can only happen during 2262 * mbedtls_ssl_read(), as opposed to mbedtls_ssl_write() and mbedtls_ssl_renegotiate() 2263 * which always behave as if max_record was 0. The reason is, 2264 * if we receive application data from the server, we need a 2265 * place to write it, which only happens during mbedtls_ssl_read(). 2266 * 2267 * \param conf SSL configuration 2268 * \param max_records Use MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to 2269 * enforce renegotiation, or a non-negative value to enforce 2270 * it but allow for a grace period of max_records records. 2271 */ 2272 void mbedtls_ssl_conf_renegotiation_enforced( mbedtls_ssl_config *conf, int max_records ); 2273 2274 /** 2275 * \brief Set record counter threshold for periodic renegotiation. 2276 * (Default: 2^48 - 1) 2277 * 2278 * Renegotiation is automatically triggered when a record 2279 * counter (outgoing or ingoing) crosses the defined 2280 * threshold. The default value is meant to prevent the 2281 * connection from being closed when the counter is about to 2282 * reached its maximal value (it is not allowed to wrap). 2283 * 2284 * Lower values can be used to enforce policies such as "keys 2285 * must be refreshed every N packets with cipher X". 2286 * 2287 * The renegotiation period can be disabled by setting 2288 * conf->disable_renegotiation to 2289 * MBEDTLS_SSL_RENEGOTIATION_DISABLED. 2290 * 2291 * \note When the configured transport is 2292 * MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation 2293 * period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM, 2294 * the maximum renegotiation period is 2^64 - 1. 2295 * 2296 * \param conf SSL configuration 2297 * \param period The threshold value: a big-endian 64-bit number. 2298 */ 2299 void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf, 2300 const unsigned char period[8] ); 2301 #endif /* MBEDTLS_SSL_RENEGOTIATION */ 2302 2303 /** 2304 * \brief Return the number of data bytes available to read 2305 * 2306 * \param ssl SSL context 2307 * 2308 * \return how many bytes are available in the read buffer 2309 */ 2310 size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl ); 2311 2312 /** 2313 * \brief Return the result of the certificate verification 2314 * 2315 * \param ssl The SSL context to use. 2316 * 2317 * \return \c 0 if the certificate verification was successful. 2318 * \return \c -1u if the result is not available. This may happen 2319 * e.g. if the handshake aborts early, or a verification 2320 * callback returned a fatal error. 2321 * \return A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX 2322 * and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h. 2323 */ 2324 uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl ); 2325 2326 /** 2327 * \brief Return the name of the current ciphersuite 2328 * 2329 * \param ssl SSL context 2330 * 2331 * \return a string containing the ciphersuite name 2332 */ 2333 const char *mbedtls_ssl_get_ciphersuite( const mbedtls_ssl_context *ssl ); 2334 2335 /** 2336 * \brief Return the current SSL version (SSLv3/TLSv1/etc) 2337 * 2338 * \param ssl SSL context 2339 * 2340 * \return a string containing the SSL version 2341 */ 2342 const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl ); 2343 2344 /** 2345 * \brief Return the (maximum) number of bytes added by the record 2346 * layer: header + encryption/MAC overhead (inc. padding) 2347 * 2348 * \param ssl SSL context 2349 * 2350 * \return Current maximum record expansion in bytes, or 2351 * MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if compression is 2352 * enabled, which makes expansion much less predictable 2353 */ 2354 int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl ); 2355 2356 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) 2357 /** 2358 * \brief Return the maximum fragment length (payload, in bytes). 2359 * This is the value negotiated with peer if any, 2360 * or the locally configured value. 2361 * 2362 * \note With DTLS, \c mbedtls_ssl_write() will return an error if 2363 * called with a larger length value. 2364 * With TLS, \c mbedtls_ssl_write() will fragment the input if 2365 * necessary and return the number of bytes written; it is up 2366 * to the caller to call \c mbedtls_ssl_write() again in 2367 * order to send the remaining bytes if any. 2368 * 2369 * \param ssl SSL context 2370 * 2371 * \return Current maximum fragment length. 2372 */ 2373 size_t mbedtls_ssl_get_max_frag_len( const mbedtls_ssl_context *ssl ); 2374 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ 2375 2376 #if defined(MBEDTLS_X509_CRT_PARSE_C) 2377 /** 2378 * \brief Return the peer certificate from the current connection 2379 * 2380 * Note: Can be NULL in case no certificate was sent during 2381 * the handshake. Different calls for the same connection can 2382 * return the same or different pointers for the same 2383 * certificate and even a different certificate altogether. 2384 * The peer cert CAN change in a single connection if 2385 * renegotiation is performed. 2386 * 2387 * \param ssl SSL context 2388 * 2389 * \return the current peer certificate 2390 */ 2391 const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert( const mbedtls_ssl_context *ssl ); 2392 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 2393 2394 #if defined(MBEDTLS_SSL_CLI_C) 2395 /** 2396 * \brief Save session in order to resume it later (client-side only) 2397 * Session data is copied to presented session structure. 2398 * 2399 * 2400 * \param ssl SSL context 2401 * \param session session context 2402 * 2403 * \return 0 if successful, 2404 * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed, 2405 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or 2406 * arguments are otherwise invalid. 2407 * 2408 * \note Only the server certificate is copied, and not the full chain, 2409 * so you should not attempt to validate the certificate again 2410 * by calling \c mbedtls_x509_crt_verify() on it. 2411 * Instead, you should use the results from the verification 2412 * in the original handshake by calling \c mbedtls_ssl_get_verify_result() 2413 * after loading the session again into a new SSL context 2414 * using \c mbedtls_ssl_set_session(). 2415 * 2416 * \note Once the session object is not needed anymore, you should 2417 * free it by calling \c mbedtls_ssl_session_free(). 2418 * 2419 * \sa mbedtls_ssl_set_session() 2420 */ 2421 int mbedtls_ssl_get_session( const mbedtls_ssl_context *ssl, mbedtls_ssl_session *session ); 2422 #endif /* MBEDTLS_SSL_CLI_C */ 2423 2424 /** 2425 * \brief Perform the SSL handshake 2426 * 2427 * \param ssl SSL context 2428 * 2429 * \return 0 if successful, or 2430 * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or 2431 * MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED (see below), or 2432 * a specific SSL error code. 2433 * 2434 * \note If this function returns something other than 0 or 2435 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2436 * becomes unusable, and you should either free it or call 2437 * \c mbedtls_ssl_session_reset() on it before re-using it for 2438 * a new connection; the current connection must be closed. 2439 * 2440 * \note If DTLS is in use, then you may choose to handle 2441 * MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging 2442 * purposes, as it is an expected return value rather than an 2443 * actual error, but you still need to reset/free the context. 2444 */ 2445 int mbedtls_ssl_handshake( mbedtls_ssl_context *ssl ); 2446 2447 /** 2448 * \brief Perform a single step of the SSL handshake 2449 * 2450 * \note The state of the context (ssl->state) will be at 2451 * the next state after execution of this function. Do not 2452 * call this function if state is MBEDTLS_SSL_HANDSHAKE_OVER. 2453 * 2454 * \note If this function returns something other than 0 or 2455 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2456 * becomes unusable, and you should either free it or call 2457 * \c mbedtls_ssl_session_reset() on it before re-using it for 2458 * a new connection; the current connection must be closed. 2459 * 2460 * \param ssl SSL context 2461 * 2462 * \return 0 if successful, or 2463 * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or 2464 * a specific SSL error code. 2465 */ 2466 int mbedtls_ssl_handshake_step( mbedtls_ssl_context *ssl ); 2467 2468 #if defined(MBEDTLS_SSL_RENEGOTIATION) 2469 /** 2470 * \brief Initiate an SSL renegotiation on the running connection. 2471 * Client: perform the renegotiation right now. 2472 * Server: request renegotiation, which will be performed 2473 * during the next call to mbedtls_ssl_read() if honored by 2474 * client. 2475 * 2476 * \param ssl SSL context 2477 * 2478 * \return 0 if successful, or any mbedtls_ssl_handshake() return 2479 * value. 2480 * 2481 * \note If this function returns something other than 0 or 2482 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2483 * becomes unusable, and you should either free it or call 2484 * \c mbedtls_ssl_session_reset() on it before re-using it for 2485 * a new connection; the current connection must be closed. 2486 */ 2487 int mbedtls_ssl_renegotiate( mbedtls_ssl_context *ssl ); 2488 #endif /* MBEDTLS_SSL_RENEGOTIATION */ 2489 2490 /** 2491 * \brief Read at most 'len' application data bytes 2492 * 2493 * \param ssl SSL context 2494 * \param buf buffer that will hold the data 2495 * \param len maximum number of bytes to read 2496 * 2497 * \return the number of bytes read, or 2498 * 0 for EOF, or 2499 * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or 2500 * MBEDTLS_ERR_SSL_CLIENT_RECONNECT (see below), or 2501 * another negative error code. 2502 * 2503 * \note If this function returns something other than a positive 2504 * value or MBEDTLS_ERR_SSL_WANT_READ/WRITE or 2505 * MBEDTLS_ERR_SSL_CLIENT_RECONNECT, then the ssl context 2506 * becomes unusable, and you should either free it or call 2507 * \c mbedtls_ssl_session_reset() on it before re-using it for 2508 * a new connection; the current connection must be closed. 2509 * 2510 * \note When this function return MBEDTLS_ERR_SSL_CLIENT_RECONNECT 2511 * (which can only happen server-side), it means that a client 2512 * is initiating a new connection using the same source port. 2513 * You can either treat that as a connection close and wait 2514 * for the client to resend a ClientHello, or directly 2515 * continue with \c mbedtls_ssl_handshake() with the same 2516 * context (as it has beeen reset internally). Either way, you 2517 * should make sure this is seen by the application as a new 2518 * connection: application state, if any, should be reset, and 2519 * most importantly the identity of the client must be checked 2520 * again. WARNING: not validating the identity of the client 2521 * again, or not transmitting the new identity to the 2522 * application layer, would allow authentication bypass! 2523 */ 2524 int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len ); 2525 2526 /** 2527 * \brief Try to write exactly 'len' application data bytes 2528 * 2529 * \warning This function will do partial writes in some cases. If the 2530 * return value is non-negative but less than length, the 2531 * function must be called again with updated arguments: 2532 * buf + ret, len - ret (if ret is the return value) until 2533 * it returns a value equal to the last 'len' argument. 2534 * 2535 * \param ssl SSL context 2536 * \param buf buffer holding the data 2537 * \param len how many bytes must be written 2538 * 2539 * \return the number of bytes actually written (may be less than len), 2540 * or MBEDTLS_ERR_SSL_WANT_WRITE or MBEDTLS_ERR_SSL_WANT_READ, 2541 * or another negative error code. 2542 * 2543 * \note If this function returns something other than 0, a positive 2544 * value or MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop 2545 * using the SSL context for reading or writing, and either 2546 * free it or call \c mbedtls_ssl_session_reset() on it before 2547 * re-using it for a new connection; the current connection 2548 * must be closed. 2549 * 2550 * \note When this function returns MBEDTLS_ERR_SSL_WANT_WRITE/READ, 2551 * it must be called later with the *same* arguments, 2552 * until it returns a value greater that or equal to 0. When 2553 * the function returns MBEDTLS_ERR_SSL_WANT_WRITE there may be 2554 * some partial data in the output buffer, however this is not 2555 * yet sent. 2556 * 2557 * \note If the requested length is greater than the maximum 2558 * fragment length (either the built-in limit or the one set 2559 * or negotiated with the peer), then: 2560 * - with TLS, less bytes than requested are written. 2561 * - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned. 2562 * \c mbedtls_ssl_get_max_frag_len() may be used to query the 2563 * active maximum fragment length. 2564 * 2565 * \note Attempting to write 0 bytes will result in an empty TLS 2566 * application record being sent. 2567 */ 2568 int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len ); 2569 2570 /** 2571 * \brief Send an alert message 2572 * 2573 * \param ssl SSL context 2574 * \param level The alert level of the message 2575 * (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL) 2576 * \param message The alert message (SSL_ALERT_MSG_*) 2577 * 2578 * \return 0 if successful, or a specific SSL error code. 2579 * 2580 * \note If this function returns something other than 0 or 2581 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2582 * becomes unusable, and you should either free it or call 2583 * \c mbedtls_ssl_session_reset() on it before re-using it for 2584 * a new connection; the current connection must be closed. 2585 */ 2586 int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl, 2587 unsigned char level, 2588 unsigned char message ); 2589 /** 2590 * \brief Notify the peer that the connection is being closed 2591 * 2592 * \param ssl SSL context 2593 * 2594 * \return 0 if successful, or a specific SSL error code. 2595 * 2596 * \note If this function returns something other than 0 or 2597 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2598 * becomes unusable, and you should either free it or call 2599 * \c mbedtls_ssl_session_reset() on it before re-using it for 2600 * a new connection; the current connection must be closed. 2601 */ 2602 int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl ); 2603 2604 /** 2605 * \brief Free referenced items in an SSL context and clear memory 2606 * 2607 * \param ssl SSL context 2608 */ 2609 void mbedtls_ssl_free( mbedtls_ssl_context *ssl ); 2610 2611 /** 2612 * \brief Initialize an SSL configuration context 2613 * Just makes the context ready for 2614 * mbedtls_ssl_config_defaults() or mbedtls_ssl_config_free(). 2615 * 2616 * \note You need to call mbedtls_ssl_config_defaults() unless you 2617 * manually set all of the relevant fields yourself. 2618 * 2619 * \param conf SSL configuration context 2620 */ 2621 void mbedtls_ssl_config_init( mbedtls_ssl_config *conf ); 2622 2623 /** 2624 * \brief Load reasonnable default SSL configuration values. 2625 * (You need to call mbedtls_ssl_config_init() first.) 2626 * 2627 * \param conf SSL configuration context 2628 * \param endpoint MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER 2629 * \param transport MBEDTLS_SSL_TRANSPORT_STREAM for TLS, or 2630 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS 2631 * \param preset a MBEDTLS_SSL_PRESET_XXX value 2632 * 2633 * \note See \c mbedtls_ssl_conf_transport() for notes on DTLS. 2634 * 2635 * \return 0 if successful, or 2636 * MBEDTLS_ERR_XXX_ALLOC_FAILED on memory allocation error. 2637 */ 2638 int mbedtls_ssl_config_defaults( mbedtls_ssl_config *conf, 2639 int endpoint, int transport, int preset ); 2640 2641 /** 2642 * \brief Free an SSL configuration context 2643 * 2644 * \param conf SSL configuration context 2645 */ 2646 void mbedtls_ssl_config_free( mbedtls_ssl_config *conf ); 2647 2648 /** 2649 * \brief Initialize SSL session structure 2650 * 2651 * \param session SSL session 2652 */ 2653 void mbedtls_ssl_session_init( mbedtls_ssl_session *session ); 2654 2655 /** 2656 * \brief Free referenced items in an SSL session including the 2657 * peer certificate and clear memory 2658 * 2659 * \note A session object can be freed even if the SSL context 2660 * that was used to retrieve the session is still in use. 2661 * 2662 * \param session SSL session 2663 */ 2664 void mbedtls_ssl_session_free( mbedtls_ssl_session *session ); 2665 2666 #ifdef __cplusplus 2667 } 2668 #endif 2669 2670 #endif /* ssl.h */ 2671