1 /** 2 * \file ssl.h 3 * 4 * \brief SSL/TLS functions. 5 */ 6 /* 7 * Copyright The Mbed TLS Contributors 8 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later 9 * 10 * This file is provided under the Apache License 2.0, or the 11 * GNU General Public License v2.0 or later. 12 * 13 * ********** 14 * Apache License 2.0: 15 * 16 * Licensed under the Apache License, Version 2.0 (the "License"); you may 17 * not use this file except in compliance with the License. 18 * You may obtain a copy of the License at 19 * 20 * http://www.apache.org/licenses/LICENSE-2.0 21 * 22 * Unless required by applicable law or agreed to in writing, software 23 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 24 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 25 * See the License for the specific language governing permissions and 26 * limitations under the License. 27 * 28 * ********** 29 * 30 * ********** 31 * GNU General Public License v2.0 or later: 32 * 33 * This program is free software; you can redistribute it and/or modify 34 * it under the terms of the GNU General Public License as published by 35 * the Free Software Foundation; either version 2 of the License, or 36 * (at your option) any later version. 37 * 38 * This program is distributed in the hope that it will be useful, 39 * but WITHOUT ANY WARRANTY; without even the implied warranty of 40 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 41 * GNU General Public License for more details. 42 * 43 * You should have received a copy of the GNU General Public License along 44 * with this program; if not, write to the Free Software Foundation, Inc., 45 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 46 * 47 * ********** 48 */ 49 #ifndef MBEDTLS_SSL_H 50 #define MBEDTLS_SSL_H 51 52 #if !defined(MBEDTLS_CONFIG_FILE) 53 #include "config.h" 54 #else 55 #include MBEDTLS_CONFIG_FILE 56 #endif 57 58 #include "bignum.h" 59 #include "ecp.h" 60 61 #include "ssl_ciphersuites.h" 62 63 #if defined(MBEDTLS_X509_CRT_PARSE_C) 64 #include "x509_crt.h" 65 #include "x509_crl.h" 66 #endif 67 68 #if defined(MBEDTLS_DHM_C) 69 #include "dhm.h" 70 #endif 71 72 #if defined(MBEDTLS_ECDH_C) 73 #include "ecdh.h" 74 #endif 75 76 #if defined(MBEDTLS_ZLIB_SUPPORT) 77 #include "zlib.h" 78 #endif 79 80 #if defined(MBEDTLS_HAVE_TIME) 81 #include "platform_time.h" 82 #endif 83 84 /* 85 * SSL Error codes 86 */ 87 #define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE -0x7080 /**< The requested feature is not available. */ 88 #define MBEDTLS_ERR_SSL_BAD_INPUT_DATA -0x7100 /**< Bad input parameters to function. */ 89 #define MBEDTLS_ERR_SSL_INVALID_MAC -0x7180 /**< Verification of the message MAC failed. */ 90 #define MBEDTLS_ERR_SSL_INVALID_RECORD -0x7200 /**< An invalid SSL record was received. */ 91 #define MBEDTLS_ERR_SSL_CONN_EOF -0x7280 /**< The connection indicated an EOF. */ 92 #define MBEDTLS_ERR_SSL_UNKNOWN_CIPHER -0x7300 /**< An unknown cipher was received. */ 93 #define MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN -0x7380 /**< The server has no ciphersuites in common with the client. */ 94 #define MBEDTLS_ERR_SSL_NO_RNG -0x7400 /**< No RNG was provided to the SSL module. */ 95 #define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE -0x7480 /**< No client certification received from the client, but required by the authentication mode. */ 96 #define MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE -0x7500 /**< Our own certificate(s) is/are too large to send in an SSL message. */ 97 #define MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED -0x7580 /**< The own certificate is not set, but needed by the server. */ 98 #define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED -0x7600 /**< The own private key or pre-shared key is not set, but needed. */ 99 #define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED -0x7680 /**< No CA Chain is set, but required to operate. */ 100 #define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE -0x7700 /**< An unexpected message was received from our peer. */ 101 #define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE -0x7780 /**< A fatal alert message was received from our peer. */ 102 #define MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED -0x7800 /**< Verification of our peer failed. */ 103 #define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY -0x7880 /**< The peer notified us that the connection is going to be closed. */ 104 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO -0x7900 /**< Processing of the ClientHello handshake message failed. */ 105 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO -0x7980 /**< Processing of the ServerHello handshake message failed. */ 106 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE -0x7A00 /**< Processing of the Certificate handshake message failed. */ 107 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST -0x7A80 /**< Processing of the CertificateRequest handshake message failed. */ 108 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE -0x7B00 /**< Processing of the ServerKeyExchange handshake message failed. */ 109 #define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE -0x7B80 /**< Processing of the ServerHelloDone handshake message failed. */ 110 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE -0x7C00 /**< Processing of the ClientKeyExchange handshake message failed. */ 111 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP -0x7C80 /**< Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Read Public. */ 112 #define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_CS -0x7D00 /**< Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Calculate Secret. */ 113 #define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY -0x7D80 /**< Processing of the CertificateVerify handshake message failed. */ 114 #define MBEDTLS_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC -0x7E00 /**< Processing of the ChangeCipherSpec handshake message failed. */ 115 #define MBEDTLS_ERR_SSL_BAD_HS_FINISHED -0x7E80 /**< Processing of the Finished handshake message failed. */ 116 #define MBEDTLS_ERR_SSL_ALLOC_FAILED -0x7F00 /**< Memory allocation failed */ 117 #define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED -0x7F80 /**< Hardware acceleration function returned with error */ 118 #define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH -0x6F80 /**< Hardware acceleration function skipped / left alone data */ 119 #define MBEDTLS_ERR_SSL_COMPRESSION_FAILED -0x6F00 /**< Processing of the compression / decompression failed */ 120 #define MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION -0x6E80 /**< Handshake protocol not within min/max boundaries */ 121 #define MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET -0x6E00 /**< Processing of the NewSessionTicket handshake message failed. */ 122 #define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED -0x6D80 /**< Session ticket has expired. */ 123 #define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH -0x6D00 /**< Public key type mismatch (eg, asked for RSA key exchange and presented EC key) */ 124 #define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY -0x6C80 /**< Unknown identity received (eg, PSK identity) */ 125 #define MBEDTLS_ERR_SSL_INTERNAL_ERROR -0x6C00 /**< Internal error (eg, unexpected failure in lower-level module) */ 126 #define MBEDTLS_ERR_SSL_COUNTER_WRAPPING -0x6B80 /**< A counter would wrap (eg, too many messages exchanged). */ 127 #define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO -0x6B00 /**< Unexpected message at ServerHello in renegotiation. */ 128 #define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED -0x6A80 /**< DTLS client must retry for hello verification */ 129 #define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL -0x6A00 /**< A buffer is too small to receive or write a message */ 130 #define MBEDTLS_ERR_SSL_NO_USABLE_CIPHERSUITE -0x6980 /**< None of the common ciphersuites is usable (eg, no suitable certificate, see debug messages). */ 131 #define MBEDTLS_ERR_SSL_WANT_READ -0x6900 /**< Connection requires a read call. */ 132 #define MBEDTLS_ERR_SSL_WANT_WRITE -0x6880 /**< Connection requires a write call. */ 133 #define MBEDTLS_ERR_SSL_TIMEOUT -0x6800 /**< The operation timed out. */ 134 #define MBEDTLS_ERR_SSL_CLIENT_RECONNECT -0x6780 /**< The client initiated a reconnect from the same port. */ 135 #define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD -0x6700 /**< Record header looks valid but is not expected. */ 136 #define MBEDTLS_ERR_SSL_NON_FATAL -0x6680 /**< The alert message received indicates a non-fatal error. */ 137 #define MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH -0x6600 /**< Couldn't set the hash for verifying CertificateVerify */ 138 #define MBEDTLS_ERR_SSL_BAD_CONFIG -0x5E80 /**< Invalid value in SSL config */ 139 140 /* 141 * Various constants 142 */ 143 #define MBEDTLS_SSL_MAJOR_VERSION_3 3 144 #define MBEDTLS_SSL_MINOR_VERSION_0 0 /*!< SSL v3.0 */ 145 #define MBEDTLS_SSL_MINOR_VERSION_1 1 /*!< TLS v1.0 */ 146 #define MBEDTLS_SSL_MINOR_VERSION_2 2 /*!< TLS v1.1 */ 147 #define MBEDTLS_SSL_MINOR_VERSION_3 3 /*!< TLS v1.2 */ 148 149 #define MBEDTLS_SSL_TRANSPORT_STREAM 0 /*!< TLS */ 150 #define MBEDTLS_SSL_TRANSPORT_DATAGRAM 1 /*!< DTLS */ 151 152 #define MBEDTLS_SSL_MAX_HOST_NAME_LEN 255 /*!< Maximum host name defined in RFC 1035 */ 153 #define MBEDTLS_SSL_MAX_ALPN_NAME_LEN 255 /*!< Maximum size in bytes of a protocol name in alpn ext., RFC 7301 */ 154 155 #define MBEDTLS_SSL_MAX_ALPN_LIST_LEN 65535 /*!< Maximum size in bytes of list in alpn ext., RFC 7301 */ 156 157 /* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c 158 * NONE must be zero so that memset()ing structure to zero works */ 159 #define MBEDTLS_SSL_MAX_FRAG_LEN_NONE 0 /*!< don't use this extension */ 160 #define MBEDTLS_SSL_MAX_FRAG_LEN_512 1 /*!< MaxFragmentLength 2^9 */ 161 #define MBEDTLS_SSL_MAX_FRAG_LEN_1024 2 /*!< MaxFragmentLength 2^10 */ 162 #define MBEDTLS_SSL_MAX_FRAG_LEN_2048 3 /*!< MaxFragmentLength 2^11 */ 163 #define MBEDTLS_SSL_MAX_FRAG_LEN_4096 4 /*!< MaxFragmentLength 2^12 */ 164 #define MBEDTLS_SSL_MAX_FRAG_LEN_INVALID 5 /*!< first invalid value */ 165 166 #define MBEDTLS_SSL_IS_CLIENT 0 167 #define MBEDTLS_SSL_IS_SERVER 1 168 169 #define MBEDTLS_SSL_IS_NOT_FALLBACK 0 170 #define MBEDTLS_SSL_IS_FALLBACK 1 171 172 #define MBEDTLS_SSL_EXTENDED_MS_DISABLED 0 173 #define MBEDTLS_SSL_EXTENDED_MS_ENABLED 1 174 175 #define MBEDTLS_SSL_ETM_DISABLED 0 176 #define MBEDTLS_SSL_ETM_ENABLED 1 177 178 #define MBEDTLS_SSL_COMPRESS_NULL 0 179 #define MBEDTLS_SSL_COMPRESS_DEFLATE 1 180 181 #define MBEDTLS_SSL_VERIFY_NONE 0 182 #define MBEDTLS_SSL_VERIFY_OPTIONAL 1 183 #define MBEDTLS_SSL_VERIFY_REQUIRED 2 184 #define MBEDTLS_SSL_VERIFY_UNSET 3 /* Used only for sni_authmode */ 185 186 #define MBEDTLS_SSL_LEGACY_RENEGOTIATION 0 187 #define MBEDTLS_SSL_SECURE_RENEGOTIATION 1 188 189 #define MBEDTLS_SSL_RENEGOTIATION_DISABLED 0 190 #define MBEDTLS_SSL_RENEGOTIATION_ENABLED 1 191 192 #define MBEDTLS_SSL_ANTI_REPLAY_DISABLED 0 193 #define MBEDTLS_SSL_ANTI_REPLAY_ENABLED 1 194 195 #define MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED -1 196 #define MBEDTLS_SSL_RENEGO_MAX_RECORDS_DEFAULT 16 197 198 #define MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION 0 199 #define MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION 1 200 #define MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE 2 201 202 #define MBEDTLS_SSL_TRUNC_HMAC_DISABLED 0 203 #define MBEDTLS_SSL_TRUNC_HMAC_ENABLED 1 204 #define MBEDTLS_SSL_TRUNCATED_HMAC_LEN 10 /* 80 bits, rfc 6066 section 7 */ 205 206 #define MBEDTLS_SSL_SESSION_TICKETS_DISABLED 0 207 #define MBEDTLS_SSL_SESSION_TICKETS_ENABLED 1 208 209 #define MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED 0 210 #define MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED 1 211 212 #define MBEDTLS_SSL_ARC4_ENABLED 0 213 #define MBEDTLS_SSL_ARC4_DISABLED 1 214 215 #define MBEDTLS_SSL_PRESET_DEFAULT 0 216 #define MBEDTLS_SSL_PRESET_SUITEB 2 217 218 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED 1 219 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 0 220 221 /* 222 * Default range for DTLS retransmission timer value, in milliseconds. 223 * RFC 6347 4.2.4.1 says from 1 second to 60 seconds. 224 */ 225 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN 1000 226 #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX 60000 227 228 /** 229 * \name SECTION: Module settings 230 * 231 * The configuration options you can set for this module are in this section. 232 * Either change them in config.h or define them on the compiler command line. 233 * \{ 234 */ 235 236 #if !defined(MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME) 237 #define MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME 86400 /**< Lifetime of session tickets (if enabled) */ 238 #endif 239 240 /* 241 * Maxium fragment length in bytes, 242 * determines the size of each of the two internal I/O buffers. 243 * 244 * Note: the RFC defines the default size of SSL / TLS messages. If you 245 * change the value here, other clients / servers may not be able to 246 * communicate with you anymore. Only change this value if you control 247 * both sides of the connection and have it reduced at both sides, or 248 * if you're using the Max Fragment Length extension and you know all your 249 * peers are using it too! 250 */ 251 #if !defined(MBEDTLS_SSL_MAX_CONTENT_LEN) 252 #define MBEDTLS_SSL_MAX_CONTENT_LEN 16384 /**< Size of the input / output buffer */ 253 #endif 254 255 /* \} name SECTION: Module settings */ 256 257 /* 258 * Length of the verify data for secure renegotiation 259 */ 260 #if defined(MBEDTLS_SSL_PROTO_SSL3) 261 #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 36 262 #else 263 #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 12 264 #endif 265 266 /* 267 * Signaling ciphersuite values (SCSV) 268 */ 269 #define MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO 0xFF /**< renegotiation info ext */ 270 #define MBEDTLS_SSL_FALLBACK_SCSV_VALUE 0x5600 /**< RFC 7507 section 2 */ 271 272 /* 273 * Supported Signature and Hash algorithms (For TLS 1.2) 274 * RFC 5246 section 7.4.1.4.1 275 */ 276 #define MBEDTLS_SSL_HASH_NONE 0 277 #define MBEDTLS_SSL_HASH_MD5 1 278 #define MBEDTLS_SSL_HASH_SHA1 2 279 #define MBEDTLS_SSL_HASH_SHA224 3 280 #define MBEDTLS_SSL_HASH_SHA256 4 281 #define MBEDTLS_SSL_HASH_SHA384 5 282 #define MBEDTLS_SSL_HASH_SHA512 6 283 284 #define MBEDTLS_SSL_SIG_ANON 0 285 #define MBEDTLS_SSL_SIG_RSA 1 286 #define MBEDTLS_SSL_SIG_ECDSA 3 287 288 /* 289 * Client Certificate Types 290 * RFC 5246 section 7.4.4 plus RFC 4492 section 5.5 291 */ 292 #define MBEDTLS_SSL_CERT_TYPE_RSA_SIGN 1 293 #define MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN 64 294 295 /* 296 * Message, alert and handshake types 297 */ 298 #define MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC 20 299 #define MBEDTLS_SSL_MSG_ALERT 21 300 #define MBEDTLS_SSL_MSG_HANDSHAKE 22 301 #define MBEDTLS_SSL_MSG_APPLICATION_DATA 23 302 303 #define MBEDTLS_SSL_ALERT_LEVEL_WARNING 1 304 #define MBEDTLS_SSL_ALERT_LEVEL_FATAL 2 305 306 #define MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY 0 /* 0x00 */ 307 #define MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE 10 /* 0x0A */ 308 #define MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC 20 /* 0x14 */ 309 #define MBEDTLS_SSL_ALERT_MSG_DECRYPTION_FAILED 21 /* 0x15 */ 310 #define MBEDTLS_SSL_ALERT_MSG_RECORD_OVERFLOW 22 /* 0x16 */ 311 #define MBEDTLS_SSL_ALERT_MSG_DECOMPRESSION_FAILURE 30 /* 0x1E */ 312 #define MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE 40 /* 0x28 */ 313 #define MBEDTLS_SSL_ALERT_MSG_NO_CERT 41 /* 0x29 */ 314 #define MBEDTLS_SSL_ALERT_MSG_BAD_CERT 42 /* 0x2A */ 315 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT 43 /* 0x2B */ 316 #define MBEDTLS_SSL_ALERT_MSG_CERT_REVOKED 44 /* 0x2C */ 317 #define MBEDTLS_SSL_ALERT_MSG_CERT_EXPIRED 45 /* 0x2D */ 318 #define MBEDTLS_SSL_ALERT_MSG_CERT_UNKNOWN 46 /* 0x2E */ 319 #define MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER 47 /* 0x2F */ 320 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_CA 48 /* 0x30 */ 321 #define MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED 49 /* 0x31 */ 322 #define MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR 50 /* 0x32 */ 323 #define MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR 51 /* 0x33 */ 324 #define MBEDTLS_SSL_ALERT_MSG_EXPORT_RESTRICTION 60 /* 0x3C */ 325 #define MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION 70 /* 0x46 */ 326 #define MBEDTLS_SSL_ALERT_MSG_INSUFFICIENT_SECURITY 71 /* 0x47 */ 327 #define MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR 80 /* 0x50 */ 328 #define MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK 86 /* 0x56 */ 329 #define MBEDTLS_SSL_ALERT_MSG_USER_CANCELED 90 /* 0x5A */ 330 #define MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION 100 /* 0x64 */ 331 #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT 110 /* 0x6E */ 332 #define MBEDTLS_SSL_ALERT_MSG_UNRECOGNIZED_NAME 112 /* 0x70 */ 333 #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY 115 /* 0x73 */ 334 #define MBEDTLS_SSL_ALERT_MSG_NO_APPLICATION_PROTOCOL 120 /* 0x78 */ 335 336 #define MBEDTLS_SSL_HS_HELLO_REQUEST 0 337 #define MBEDTLS_SSL_HS_CLIENT_HELLO 1 338 #define MBEDTLS_SSL_HS_SERVER_HELLO 2 339 #define MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST 3 340 #define MBEDTLS_SSL_HS_NEW_SESSION_TICKET 4 341 #define MBEDTLS_SSL_HS_CERTIFICATE 11 342 #define MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE 12 343 #define MBEDTLS_SSL_HS_CERTIFICATE_REQUEST 13 344 #define MBEDTLS_SSL_HS_SERVER_HELLO_DONE 14 345 #define MBEDTLS_SSL_HS_CERTIFICATE_VERIFY 15 346 #define MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE 16 347 #define MBEDTLS_SSL_HS_FINISHED 20 348 349 /* 350 * TLS extensions 351 */ 352 #define MBEDTLS_TLS_EXT_SERVERNAME 0 353 #define MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME 0 354 355 #define MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH 1 356 357 #define MBEDTLS_TLS_EXT_TRUNCATED_HMAC 4 358 359 #define MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES 10 360 #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS 11 361 362 #define MBEDTLS_TLS_EXT_SIG_ALG 13 363 364 #define MBEDTLS_TLS_EXT_ALPN 16 365 366 #define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC 22 /* 0x16 */ 367 #define MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET 0x0017 /* 23 */ 368 369 #define MBEDTLS_TLS_EXT_SESSION_TICKET 35 370 371 #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP 256 /* experimental */ 372 373 #define MBEDTLS_TLS_EXT_RENEGOTIATION_INFO 0xFF01 374 375 /* 376 * Size defines 377 */ 378 #if !defined(MBEDTLS_PSK_MAX_LEN) 379 #define MBEDTLS_PSK_MAX_LEN 32 /* 256 bits */ 380 #endif 381 382 /* Dummy type used only for its size */ 383 union mbedtls_ssl_premaster_secret 384 { 385 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) 386 unsigned char _pms_rsa[48]; /* RFC 5246 8.1.1 */ 387 #endif 388 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) 389 unsigned char _pms_dhm[MBEDTLS_MPI_MAX_SIZE]; /* RFC 5246 8.1.2 */ 390 #endif 391 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ 392 defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ 393 defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ 394 defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) 395 unsigned char _pms_ecdh[MBEDTLS_ECP_MAX_BYTES]; /* RFC 4492 5.10 */ 396 #endif 397 #if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) 398 unsigned char _pms_psk[4 + 2 * MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 2 */ 399 #endif 400 #if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) 401 unsigned char _pms_dhe_psk[4 + MBEDTLS_MPI_MAX_SIZE 402 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 3 */ 403 #endif 404 #if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) 405 unsigned char _pms_rsa_psk[52 + MBEDTLS_PSK_MAX_LEN]; /* RFC 4279 4 */ 406 #endif 407 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) 408 unsigned char _pms_ecdhe_psk[4 + MBEDTLS_ECP_MAX_BYTES 409 + MBEDTLS_PSK_MAX_LEN]; /* RFC 5489 2 */ 410 #endif 411 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) 412 unsigned char _pms_ecjpake[32]; /* Thread spec: SHA-256 output */ 413 #endif 414 }; 415 416 #define MBEDTLS_PREMASTER_SIZE sizeof( union mbedtls_ssl_premaster_secret ) 417 418 #ifdef __cplusplus 419 extern "C" { 420 #endif 421 422 /* 423 * SSL state machine 424 */ 425 typedef enum 426 { 427 MBEDTLS_SSL_HELLO_REQUEST, 428 MBEDTLS_SSL_CLIENT_HELLO, 429 MBEDTLS_SSL_SERVER_HELLO, 430 MBEDTLS_SSL_SERVER_CERTIFICATE, 431 MBEDTLS_SSL_SERVER_KEY_EXCHANGE, 432 MBEDTLS_SSL_CERTIFICATE_REQUEST, 433 MBEDTLS_SSL_SERVER_HELLO_DONE, 434 MBEDTLS_SSL_CLIENT_CERTIFICATE, 435 MBEDTLS_SSL_CLIENT_KEY_EXCHANGE, 436 MBEDTLS_SSL_CERTIFICATE_VERIFY, 437 MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC, 438 MBEDTLS_SSL_CLIENT_FINISHED, 439 MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC, 440 MBEDTLS_SSL_SERVER_FINISHED, 441 MBEDTLS_SSL_FLUSH_BUFFERS, 442 MBEDTLS_SSL_HANDSHAKE_WRAPUP, 443 MBEDTLS_SSL_HANDSHAKE_OVER, 444 MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET, 445 MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT, 446 } 447 mbedtls_ssl_states; 448 449 /** 450 * \brief Callback type: send data on the network. 451 * 452 * \note That callback may be either blocking or non-blocking. 453 * 454 * \param ctx Context for the send callback (typically a file descriptor) 455 * \param buf Buffer holding the data to send 456 * \param len Length of the data to send 457 * 458 * \return The callback must return the number of bytes sent if any, 459 * or a non-zero error code. 460 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_WRITE 461 * must be returned when the operation would block. 462 * 463 * \note The callback is allowed to send fewer bytes than requested. 464 * It must always return the number of bytes actually sent. 465 */ 466 typedef int mbedtls_ssl_send_t( void *ctx, 467 const unsigned char *buf, 468 size_t len ); 469 470 /** 471 * \brief Callback type: receive data from the network. 472 * 473 * \note That callback may be either blocking or non-blocking. 474 * 475 * \param ctx Context for the receive callback (typically a file 476 * descriptor) 477 * \param buf Buffer to write the received data to 478 * \param len Length of the receive buffer 479 * 480 * \return The callback must return the number of bytes received, 481 * or a non-zero error code. 482 * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ 483 * must be returned when the operation would block. 484 * 485 * \note The callback may receive fewer bytes than the length of the 486 * buffer. It must always return the number of bytes actually 487 * received and written to the buffer. 488 */ 489 typedef int mbedtls_ssl_recv_t( void *ctx, 490 unsigned char *buf, 491 size_t len ); 492 493 /** 494 * \brief Callback type: receive data from the network, with timeout 495 * 496 * \note That callback must block until data is received, or the 497 * timeout delay expires, or the operation is interrupted by a 498 * signal. 499 * 500 * \param ctx Context for the receive callback (typically a file descriptor) 501 * \param buf Buffer to write the received data to 502 * \param len Length of the receive buffer 503 * \param timeout Maximum nomber of millisecondes to wait for data 504 * 0 means no timeout (potentially waiting forever) 505 * 506 * \return The callback must return the number of bytes received, 507 * or a non-zero error code: 508 * \c MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out, 509 * \c MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal. 510 * 511 * \note The callback may receive fewer bytes than the length of the 512 * buffer. It must always return the number of bytes actually 513 * received and written to the buffer. 514 */ 515 typedef int mbedtls_ssl_recv_timeout_t( void *ctx, 516 unsigned char *buf, 517 size_t len, 518 uint32_t timeout ); 519 /** 520 * \brief Callback type: set a pair of timers/delays to watch 521 * 522 * \param ctx Context pointer 523 * \param int_ms Intermediate delay in milliseconds 524 * \param fin_ms Final delay in milliseconds 525 * 0 cancels the current timer. 526 * 527 * \note This callback must at least store the necessary information 528 * for the associated \c mbedtls_ssl_get_timer_t callback to 529 * return correct information. 530 * 531 * \note If using a event-driven style of programming, an event must 532 * be generated when the final delay is passed. The event must 533 * cause a call to \c mbedtls_ssl_handshake() with the proper 534 * SSL context to be scheduled. Care must be taken to ensure 535 * that at most one such call happens at a time. 536 * 537 * \note Only one timer at a time must be running. Calling this 538 * function while a timer is running must cancel it. Cancelled 539 * timers must not generate any event. 540 */ 541 typedef void mbedtls_ssl_set_timer_t( void * ctx, 542 uint32_t int_ms, 543 uint32_t fin_ms ); 544 545 /** 546 * \brief Callback type: get status of timers/delays 547 * 548 * \param ctx Context pointer 549 * 550 * \return This callback must return: 551 * -1 if cancelled (fin_ms == 0), 552 * 0 if none of the delays have passed, 553 * 1 if only the intermediate delay has passed, 554 * 2 if the final delay has passed. 555 */ 556 typedef int mbedtls_ssl_get_timer_t( void * ctx ); 557 558 559 /* Defined below */ 560 typedef struct mbedtls_ssl_session mbedtls_ssl_session; 561 typedef struct mbedtls_ssl_context mbedtls_ssl_context; 562 typedef struct mbedtls_ssl_config mbedtls_ssl_config; 563 564 /* Defined in ssl_internal.h */ 565 typedef struct mbedtls_ssl_transform mbedtls_ssl_transform; 566 typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params; 567 typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t; 568 #if defined(MBEDTLS_X509_CRT_PARSE_C) 569 typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert; 570 #endif 571 #if defined(MBEDTLS_SSL_PROTO_DTLS) 572 typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item; 573 #endif 574 575 /* 576 * This structure is used for storing current session data. 577 */ 578 struct mbedtls_ssl_session 579 { 580 #if defined(MBEDTLS_HAVE_TIME) 581 mbedtls_time_t start; /*!< starting time */ 582 #endif 583 int ciphersuite; /*!< chosen ciphersuite */ 584 int compression; /*!< chosen compression */ 585 size_t id_len; /*!< session id length */ 586 unsigned char id[32]; /*!< session identifier */ 587 unsigned char master[48]; /*!< the master secret */ 588 589 #if defined(MBEDTLS_X509_CRT_PARSE_C) 590 mbedtls_x509_crt *peer_cert; /*!< peer X.509 cert chain */ 591 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 592 uint32_t verify_result; /*!< verification result */ 593 594 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C) 595 unsigned char *ticket; /*!< RFC 5077 session ticket */ 596 size_t ticket_len; /*!< session ticket length */ 597 uint32_t ticket_lifetime; /*!< ticket lifetime hint */ 598 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */ 599 600 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) 601 unsigned char mfl_code; /*!< MaxFragmentLength negotiated by peer */ 602 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ 603 604 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC) 605 int trunc_hmac; /*!< flag for truncated hmac activation */ 606 #endif /* MBEDTLS_SSL_TRUNCATED_HMAC */ 607 608 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) 609 int encrypt_then_mac; /*!< flag for EtM activation */ 610 #endif 611 }; 612 613 /** 614 * SSL/TLS configuration to be shared between mbedtls_ssl_context structures. 615 */ 616 struct mbedtls_ssl_config 617 { 618 /* Group items by size (largest first) to minimize padding overhead */ 619 620 /* 621 * Pointers 622 */ 623 624 const int *ciphersuite_list[4]; /*!< allowed ciphersuites per version */ 625 626 /** Callback for printing debug output */ 627 void (*f_dbg)(void *, int, const char *, int, const char *); 628 void *p_dbg; /*!< context for the debug function */ 629 630 /** Callback for getting (pseudo-)random numbers */ 631 int (*f_rng)(void *, unsigned char *, size_t); 632 void *p_rng; /*!< context for the RNG function */ 633 634 /** Callback to retrieve a session from the cache */ 635 int (*f_get_cache)(void *, mbedtls_ssl_session *); 636 /** Callback to store a session into the cache */ 637 int (*f_set_cache)(void *, const mbedtls_ssl_session *); 638 void *p_cache; /*!< context for cache callbacks */ 639 640 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) 641 /** Callback for setting cert according to SNI extension */ 642 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, size_t); 643 void *p_sni; /*!< context for SNI callback */ 644 #endif 645 646 #if defined(MBEDTLS_X509_CRT_PARSE_C) 647 /** Callback to customize X.509 certificate chain verification */ 648 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *); 649 void *p_vrfy; /*!< context for X.509 verify calllback */ 650 #endif 651 652 #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) 653 /** Callback to retrieve PSK key from identity */ 654 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, size_t); 655 void *p_psk; /*!< context for PSK callback */ 656 #endif 657 658 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) 659 /** Callback to create & write a cookie for ClientHello veirifcation */ 660 int (*f_cookie_write)( void *, unsigned char **, unsigned char *, 661 const unsigned char *, size_t ); 662 /** Callback to verify validity of a ClientHello cookie */ 663 int (*f_cookie_check)( void *, const unsigned char *, size_t, 664 const unsigned char *, size_t ); 665 void *p_cookie; /*!< context for the cookie callbacks */ 666 #endif 667 668 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C) 669 /** Callback to create & write a session ticket */ 670 int (*f_ticket_write)( void *, const mbedtls_ssl_session *, 671 unsigned char *, const unsigned char *, size_t *, uint32_t * ); 672 /** Callback to parse a session ticket into a session structure */ 673 int (*f_ticket_parse)( void *, mbedtls_ssl_session *, unsigned char *, size_t); 674 void *p_ticket; /*!< context for the ticket callbacks */ 675 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */ 676 677 #if defined(MBEDTLS_SSL_EXPORT_KEYS) 678 /** Callback to export key block and master secret */ 679 int (*f_export_keys)( void *, const unsigned char *, 680 const unsigned char *, size_t, size_t, size_t ); 681 void *p_export_keys; /*!< context for key export callback */ 682 #endif 683 684 #if defined(MBEDTLS_X509_CRT_PARSE_C) 685 const mbedtls_x509_crt_profile *cert_profile; /*!< verification profile */ 686 mbedtls_ssl_key_cert *key_cert; /*!< own certificate/key pair(s) */ 687 mbedtls_x509_crt *ca_chain; /*!< trusted CAs */ 688 mbedtls_x509_crl *ca_crl; /*!< trusted CAs CRLs */ 689 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 690 691 #if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) 692 const int *sig_hashes; /*!< allowed signature hashes */ 693 #endif 694 695 #if defined(MBEDTLS_ECP_C) 696 const mbedtls_ecp_group_id *curve_list; /*!< allowed curves */ 697 #endif 698 699 #if defined(MBEDTLS_DHM_C) 700 mbedtls_mpi dhm_P; /*!< prime modulus for DHM */ 701 mbedtls_mpi dhm_G; /*!< generator for DHM */ 702 #endif 703 704 #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) 705 unsigned char *psk; /*!< pre-shared key */ 706 size_t psk_len; /*!< length of the pre-shared key */ 707 unsigned char *psk_identity; /*!< identity for PSK negotiation */ 708 size_t psk_identity_len;/*!< length of identity */ 709 #endif 710 711 #if defined(MBEDTLS_SSL_ALPN) 712 const char **alpn_list; /*!< ordered list of protocols */ 713 #endif 714 715 /* 716 * Numerical settings (int then char) 717 */ 718 719 uint32_t read_timeout; /*!< timeout for mbedtls_ssl_read (ms) */ 720 721 #if defined(MBEDTLS_SSL_PROTO_DTLS) 722 uint32_t hs_timeout_min; /*!< initial value of the handshake 723 retransmission timeout (ms) */ 724 uint32_t hs_timeout_max; /*!< maximum value of the handshake 725 retransmission timeout (ms) */ 726 #endif 727 728 #if defined(MBEDTLS_SSL_RENEGOTIATION) 729 int renego_max_records; /*!< grace period for renegotiation */ 730 unsigned char renego_period[8]; /*!< value of the record counters 731 that triggers renegotiation */ 732 #endif 733 734 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT) 735 unsigned int badmac_limit; /*!< limit of records with a bad MAC */ 736 #endif 737 738 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C) 739 unsigned int dhm_min_bitlen; /*!< min. bit length of the DHM prime */ 740 #endif 741 742 unsigned char max_major_ver; /*!< max. major version used */ 743 unsigned char max_minor_ver; /*!< max. minor version used */ 744 unsigned char min_major_ver; /*!< min. major version used */ 745 unsigned char min_minor_ver; /*!< min. minor version used */ 746 747 /* 748 * Flags (bitfields) 749 */ 750 751 unsigned int endpoint : 1; /*!< 0: client, 1: server */ 752 unsigned int transport : 1; /*!< stream (TLS) or datagram (DTLS) */ 753 unsigned int authmode : 2; /*!< MBEDTLS_SSL_VERIFY_XXX */ 754 /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE */ 755 unsigned int allow_legacy_renegotiation : 2 ; /*!< MBEDTLS_LEGACY_XXX */ 756 #if defined(MBEDTLS_ARC4_C) 757 unsigned int arc4_disabled : 1; /*!< blacklist RC4 ciphersuites? */ 758 #endif 759 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) 760 unsigned int mfl_code : 3; /*!< desired fragment length */ 761 #endif 762 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) 763 unsigned int encrypt_then_mac : 1 ; /*!< negotiate encrypt-then-mac? */ 764 #endif 765 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) 766 unsigned int extended_ms : 1; /*!< negotiate extended master secret? */ 767 #endif 768 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) 769 unsigned int anti_replay : 1; /*!< detect and prevent replay? */ 770 #endif 771 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING) 772 unsigned int cbc_record_splitting : 1; /*!< do cbc record splitting */ 773 #endif 774 #if defined(MBEDTLS_SSL_RENEGOTIATION) 775 unsigned int disable_renegotiation : 1; /*!< disable renegotiation? */ 776 #endif 777 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC) 778 unsigned int trunc_hmac : 1; /*!< negotiate truncated hmac? */ 779 #endif 780 #if defined(MBEDTLS_SSL_SESSION_TICKETS) 781 unsigned int session_tickets : 1; /*!< use session tickets? */ 782 #endif 783 #if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C) 784 unsigned int fallback : 1; /*!< is this a fallback? */ 785 #endif 786 #if defined(MBEDTLS_SSL_SRV_C) 787 unsigned int cert_req_ca_list : 1; /*!< enable sending CA list in 788 Certificate Request messages? */ 789 #endif 790 }; 791 792 793 struct mbedtls_ssl_context 794 { 795 const mbedtls_ssl_config *conf; /*!< configuration information */ 796 797 /* 798 * Miscellaneous 799 */ 800 int state; /*!< SSL handshake: current state */ 801 #if defined(MBEDTLS_SSL_RENEGOTIATION) 802 int renego_status; /*!< Initial, in progress, pending? */ 803 int renego_records_seen; /*!< Records since renego request, or with DTLS, 804 number of retransmissions of request if 805 renego_max_records is < 0 */ 806 #endif 807 808 int major_ver; /*!< equal to MBEDTLS_SSL_MAJOR_VERSION_3 */ 809 int minor_ver; /*!< either 0 (SSL3) or 1 (TLS1.0) */ 810 811 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT) 812 unsigned badmac_seen; /*!< records with a bad MAC received */ 813 #endif 814 815 mbedtls_ssl_send_t *f_send; /*!< Callback for network send */ 816 mbedtls_ssl_recv_t *f_recv; /*!< Callback for network receive */ 817 mbedtls_ssl_recv_timeout_t *f_recv_timeout; 818 /*!< Callback for network receive with timeout */ 819 820 void *p_bio; /*!< context for I/O operations */ 821 822 /* 823 * Session layer 824 */ 825 mbedtls_ssl_session *session_in; /*!< current session data (in) */ 826 mbedtls_ssl_session *session_out; /*!< current session data (out) */ 827 mbedtls_ssl_session *session; /*!< negotiated session data */ 828 mbedtls_ssl_session *session_negotiate; /*!< session data in negotiation */ 829 830 mbedtls_ssl_handshake_params *handshake; /*!< params required only during 831 the handshake process */ 832 833 /* 834 * Record layer transformations 835 */ 836 mbedtls_ssl_transform *transform_in; /*!< current transform params (in) */ 837 mbedtls_ssl_transform *transform_out; /*!< current transform params (in) */ 838 mbedtls_ssl_transform *transform; /*!< negotiated transform params */ 839 mbedtls_ssl_transform *transform_negotiate; /*!< transform params in negotiation */ 840 841 /* 842 * Timers 843 */ 844 void *p_timer; /*!< context for the timer callbacks */ 845 846 mbedtls_ssl_set_timer_t *f_set_timer; /*!< set timer callback */ 847 mbedtls_ssl_get_timer_t *f_get_timer; /*!< get timer callback */ 848 849 /* 850 * Record layer (incoming data) 851 */ 852 unsigned char *in_buf; /*!< input buffer */ 853 unsigned char *in_ctr; /*!< 64-bit incoming message counter 854 TLS: maintained by us 855 DTLS: read from peer */ 856 unsigned char *in_hdr; /*!< start of record header */ 857 unsigned char *in_len; /*!< two-bytes message length field */ 858 unsigned char *in_iv; /*!< ivlen-byte IV */ 859 unsigned char *in_msg; /*!< message contents (in_iv+ivlen) */ 860 unsigned char *in_offt; /*!< read offset in application data */ 861 862 int in_msgtype; /*!< record header: message type */ 863 size_t in_msglen; /*!< record header: message length */ 864 size_t in_left; /*!< amount of data read so far */ 865 #if defined(MBEDTLS_SSL_PROTO_DTLS) 866 uint16_t in_epoch; /*!< DTLS epoch for incoming records */ 867 size_t next_record_offset; /*!< offset of the next record in datagram 868 (equal to in_left if none) */ 869 #endif 870 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) 871 uint64_t in_window_top; /*!< last validated record seq_num */ 872 uint64_t in_window; /*!< bitmask for replay detection */ 873 #endif 874 875 size_t in_hslen; /*!< current handshake message length, 876 including the handshake header */ 877 int nb_zero; /*!< # of 0-length encrypted messages */ 878 879 int keep_current_message; /*!< drop or reuse current message 880 on next call to record layer? */ 881 882 /* 883 * Record layer (outgoing data) 884 */ 885 unsigned char *out_buf; /*!< output buffer */ 886 unsigned char *out_ctr; /*!< 64-bit outgoing message counter */ 887 unsigned char *out_hdr; /*!< start of record header */ 888 unsigned char *out_len; /*!< two-bytes message length field */ 889 unsigned char *out_iv; /*!< ivlen-byte IV */ 890 unsigned char *out_msg; /*!< message contents (out_iv+ivlen) */ 891 892 int out_msgtype; /*!< record header: message type */ 893 size_t out_msglen; /*!< record header: message length */ 894 size_t out_left; /*!< amount of data not yet written */ 895 896 #if defined(MBEDTLS_ZLIB_SUPPORT) 897 unsigned char *compress_buf; /*!< zlib data buffer */ 898 #endif 899 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING) 900 signed char split_done; /*!< current record already splitted? */ 901 #endif 902 903 /* 904 * PKI layer 905 */ 906 int client_auth; /*!< flag for client auth. */ 907 908 /* 909 * User settings 910 */ 911 #if defined(MBEDTLS_X509_CRT_PARSE_C) 912 char *hostname; /*!< expected peer CN for verification 913 (and SNI if available) */ 914 #endif 915 916 #if defined(MBEDTLS_SSL_ALPN) 917 const char *alpn_chosen; /*!< negotiated protocol */ 918 #endif 919 920 /* 921 * Information for DTLS hello verify 922 */ 923 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) 924 unsigned char *cli_id; /*!< transport-level ID of the client */ 925 size_t cli_id_len; /*!< length of cli_id */ 926 #endif 927 928 /* 929 * Secure renegotiation 930 */ 931 /* needed to know when to send extension on server */ 932 int secure_renegotiation; /*!< does peer support legacy or 933 secure renegotiation */ 934 #if defined(MBEDTLS_SSL_RENEGOTIATION) 935 size_t verify_data_len; /*!< length of verify data stored */ 936 char own_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */ 937 char peer_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */ 938 #endif 939 }; 940 941 #if defined(MBEDTLS_SSL_HW_RECORD_ACCEL) 942 943 #define MBEDTLS_SSL_CHANNEL_OUTBOUND 0 944 #define MBEDTLS_SSL_CHANNEL_INBOUND 1 945 946 extern int (*mbedtls_ssl_hw_record_init)(mbedtls_ssl_context *ssl, 947 const unsigned char *key_enc, const unsigned char *key_dec, 948 size_t keylen, 949 const unsigned char *iv_enc, const unsigned char *iv_dec, 950 size_t ivlen, 951 const unsigned char *mac_enc, const unsigned char *mac_dec, 952 size_t maclen); 953 extern int (*mbedtls_ssl_hw_record_activate)(mbedtls_ssl_context *ssl, int direction); 954 extern int (*mbedtls_ssl_hw_record_reset)(mbedtls_ssl_context *ssl); 955 extern int (*mbedtls_ssl_hw_record_write)(mbedtls_ssl_context *ssl); 956 extern int (*mbedtls_ssl_hw_record_read)(mbedtls_ssl_context *ssl); 957 extern int (*mbedtls_ssl_hw_record_finish)(mbedtls_ssl_context *ssl); 958 #endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */ 959 960 /** 961 * \brief Return the name of the ciphersuite associated with the 962 * given ID 963 * 964 * \param ciphersuite_id SSL ciphersuite ID 965 * 966 * \return a string containing the ciphersuite name 967 */ 968 const char *mbedtls_ssl_get_ciphersuite_name( const int ciphersuite_id ); 969 970 /** 971 * \brief Return the ID of the ciphersuite associated with the 972 * given name 973 * 974 * \param ciphersuite_name SSL ciphersuite name 975 * 976 * \return the ID with the ciphersuite or 0 if not found 977 */ 978 int mbedtls_ssl_get_ciphersuite_id( const char *ciphersuite_name ); 979 980 /** 981 * \brief Initialize an SSL context 982 * Just makes the context ready for mbedtls_ssl_setup() or 983 * mbedtls_ssl_free() 984 * 985 * \param ssl SSL context 986 */ 987 void mbedtls_ssl_init( mbedtls_ssl_context *ssl ); 988 989 /** 990 * \brief Set up an SSL context for use 991 * 992 * \note No copy of the configuration context is made, it can be 993 * shared by many mbedtls_ssl_context structures. 994 * 995 * \warning The conf structure will be accessed during the session. 996 * It must not be modified or freed as long as the session 997 * is active. 998 * 999 * \warning This function must be called exactly once per context. 1000 * Calling mbedtls_ssl_setup again is not supported, even 1001 * if no session is active. 1002 * 1003 * \param ssl SSL context 1004 * \param conf SSL configuration to use 1005 * 1006 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED if 1007 * memory allocation failed 1008 */ 1009 int mbedtls_ssl_setup( mbedtls_ssl_context *ssl, 1010 const mbedtls_ssl_config *conf ); 1011 1012 /** 1013 * \brief Reset an already initialized SSL context for re-use 1014 * while retaining application-set variables, function 1015 * pointers and data. 1016 * 1017 * \param ssl SSL context 1018 * \return 0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED, 1019 MBEDTLS_ERR_SSL_HW_ACCEL_FAILED or 1020 * MBEDTLS_ERR_SSL_COMPRESSION_FAILED 1021 */ 1022 int mbedtls_ssl_session_reset( mbedtls_ssl_context *ssl ); 1023 1024 /** 1025 * \brief Set the current endpoint type 1026 * 1027 * \param conf SSL configuration 1028 * \param endpoint must be MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER 1029 */ 1030 void mbedtls_ssl_conf_endpoint( mbedtls_ssl_config *conf, int endpoint ); 1031 1032 /** 1033 * \brief Set the transport type (TLS or DTLS). 1034 * Default: TLS 1035 * 1036 * \note For DTLS, you must either provide a recv callback that 1037 * doesn't block, or one that handles timeouts, see 1038 * \c mbedtls_ssl_set_bio(). You also need to provide timer 1039 * callbacks with \c mbedtls_ssl_set_timer_cb(). 1040 * 1041 * \param conf SSL configuration 1042 * \param transport transport type: 1043 * MBEDTLS_SSL_TRANSPORT_STREAM for TLS, 1044 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS. 1045 */ 1046 void mbedtls_ssl_conf_transport( mbedtls_ssl_config *conf, int transport ); 1047 1048 /** 1049 * \brief Set the certificate verification mode 1050 * Default: NONE on server, REQUIRED on client 1051 * 1052 * \param conf SSL configuration 1053 * \param authmode can be: 1054 * 1055 * MBEDTLS_SSL_VERIFY_NONE: peer certificate is not checked 1056 * (default on server) 1057 * (insecure on client) 1058 * 1059 * MBEDTLS_SSL_VERIFY_OPTIONAL: peer certificate is checked, however the 1060 * handshake continues even if verification failed; 1061 * mbedtls_ssl_get_verify_result() can be called after the 1062 * handshake is complete. 1063 * 1064 * MBEDTLS_SSL_VERIFY_REQUIRED: peer *must* present a valid certificate, 1065 * handshake is aborted if verification failed. 1066 * (default on client) 1067 * 1068 * \note On client, MBEDTLS_SSL_VERIFY_REQUIRED is the recommended mode. 1069 * With MBEDTLS_SSL_VERIFY_OPTIONAL, the user needs to call mbedtls_ssl_get_verify_result() at 1070 * the right time(s), which may not be obvious, while REQUIRED always perform 1071 * the verification as soon as possible. For example, REQUIRED was protecting 1072 * against the "triple handshake" attack even before it was found. 1073 */ 1074 void mbedtls_ssl_conf_authmode( mbedtls_ssl_config *conf, int authmode ); 1075 1076 #if defined(MBEDTLS_X509_CRT_PARSE_C) 1077 /** 1078 * \brief Set the verification callback (Optional). 1079 * 1080 * If set, the verify callback is called for each 1081 * certificate in the chain. For implementation 1082 * information, please see \c mbedtls_x509_crt_verify() 1083 * 1084 * \param conf SSL configuration 1085 * \param f_vrfy verification function 1086 * \param p_vrfy verification parameter 1087 */ 1088 void mbedtls_ssl_conf_verify( mbedtls_ssl_config *conf, 1089 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *), 1090 void *p_vrfy ); 1091 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 1092 1093 /** 1094 * \brief Set the random number generator callback 1095 * 1096 * \param conf SSL configuration 1097 * \param f_rng RNG function 1098 * \param p_rng RNG parameter 1099 */ 1100 void mbedtls_ssl_conf_rng( mbedtls_ssl_config *conf, 1101 int (*f_rng)(void *, unsigned char *, size_t), 1102 void *p_rng ); 1103 1104 /** 1105 * \brief Set the debug callback 1106 * 1107 * The callback has the following argument: 1108 * void * opaque context for the callback 1109 * int debug level 1110 * const char * file name 1111 * int line number 1112 * const char * message 1113 * 1114 * \param conf SSL configuration 1115 * \param f_dbg debug function 1116 * \param p_dbg debug parameter 1117 */ 1118 void mbedtls_ssl_conf_dbg( mbedtls_ssl_config *conf, 1119 void (*f_dbg)(void *, int, const char *, int, const char *), 1120 void *p_dbg ); 1121 1122 /** 1123 * \brief Set the underlying BIO callbacks for write, read and 1124 * read-with-timeout. 1125 * 1126 * \param ssl SSL context 1127 * \param p_bio parameter (context) shared by BIO callbacks 1128 * \param f_send write callback 1129 * \param f_recv read callback 1130 * \param f_recv_timeout blocking read callback with timeout. 1131 * 1132 * \note One of f_recv or f_recv_timeout can be NULL, in which case 1133 * the other is used. If both are non-NULL, f_recv_timeout is 1134 * used and f_recv is ignored (as if it were NULL). 1135 * 1136 * \note The two most common use cases are: 1137 * - non-blocking I/O, f_recv != NULL, f_recv_timeout == NULL 1138 * - blocking I/O, f_recv == NULL, f_recv_timout != NULL 1139 * 1140 * \note For DTLS, you need to provide either a non-NULL 1141 * f_recv_timeout callback, or a f_recv that doesn't block. 1142 * 1143 * \note See the documentations of \c mbedtls_ssl_send_t, 1144 * \c mbedtls_ssl_recv_t and \c mbedtls_ssl_recv_timeout_t for 1145 * the conventions those callbacks must follow. 1146 * 1147 * \note On some platforms, net_sockets.c provides 1148 * \c mbedtls_net_send(), \c mbedtls_net_recv() and 1149 * \c mbedtls_net_recv_timeout() that are suitable to be used 1150 * here. 1151 */ 1152 void mbedtls_ssl_set_bio( mbedtls_ssl_context *ssl, 1153 void *p_bio, 1154 mbedtls_ssl_send_t *f_send, 1155 mbedtls_ssl_recv_t *f_recv, 1156 mbedtls_ssl_recv_timeout_t *f_recv_timeout ); 1157 1158 /** 1159 * \brief Set the timeout period for mbedtls_ssl_read() 1160 * (Default: no timeout.) 1161 * 1162 * \param conf SSL configuration context 1163 * \param timeout Timeout value in milliseconds. 1164 * Use 0 for no timeout (default). 1165 * 1166 * \note With blocking I/O, this will only work if a non-NULL 1167 * \c f_recv_timeout was set with \c mbedtls_ssl_set_bio(). 1168 * With non-blocking I/O, this will only work if timer 1169 * callbacks were set with \c mbedtls_ssl_set_timer_cb(). 1170 * 1171 * \note With non-blocking I/O, you may also skip this function 1172 * altogether and handle timeouts at the application layer. 1173 */ 1174 void mbedtls_ssl_conf_read_timeout( mbedtls_ssl_config *conf, uint32_t timeout ); 1175 1176 /** 1177 * \brief Set the timer callbacks (Mandatory for DTLS.) 1178 * 1179 * \param ssl SSL context 1180 * \param p_timer parameter (context) shared by timer callbacks 1181 * \param f_set_timer set timer callback 1182 * \param f_get_timer get timer callback. Must return: 1183 * 1184 * \note See the documentation of \c mbedtls_ssl_set_timer_t and 1185 * \c mbedtls_ssl_get_timer_t for the conventions this pair of 1186 * callbacks must follow. 1187 * 1188 * \note On some platforms, timing.c provides 1189 * \c mbedtls_timing_set_delay() and 1190 * \c mbedtls_timing_get_delay() that are suitable for using 1191 * here, except if using an event-driven style. 1192 * 1193 * \note See also the "DTLS tutorial" article in our knowledge base. 1194 * https://tls.mbed.org/kb/how-to/dtls-tutorial 1195 */ 1196 void mbedtls_ssl_set_timer_cb( mbedtls_ssl_context *ssl, 1197 void *p_timer, 1198 mbedtls_ssl_set_timer_t *f_set_timer, 1199 mbedtls_ssl_get_timer_t *f_get_timer ); 1200 1201 /** 1202 * \brief Callback type: generate and write session ticket 1203 * 1204 * \note This describes what a callback implementation should do. 1205 * This callback should generate an encrypted and 1206 * authenticated ticket for the session and write it to the 1207 * output buffer. Here, ticket means the opaque ticket part 1208 * of the NewSessionTicket structure of RFC 5077. 1209 * 1210 * \param p_ticket Context for the callback 1211 * \param session SSL session to be written in the ticket 1212 * \param start Start of the output buffer 1213 * \param end End of the output buffer 1214 * \param tlen On exit, holds the length written 1215 * \param lifetime On exit, holds the lifetime of the ticket in seconds 1216 * 1217 * \return 0 if successful, or 1218 * a specific MBEDTLS_ERR_XXX code. 1219 */ 1220 typedef int mbedtls_ssl_ticket_write_t( void *p_ticket, 1221 const mbedtls_ssl_session *session, 1222 unsigned char *start, 1223 const unsigned char *end, 1224 size_t *tlen, 1225 uint32_t *lifetime ); 1226 1227 #if defined(MBEDTLS_SSL_EXPORT_KEYS) 1228 /** 1229 * \brief Callback type: Export key block and master secret 1230 * 1231 * \note This is required for certain uses of TLS, e.g. EAP-TLS 1232 * (RFC 5216) and Thread. The key pointers are ephemeral and 1233 * therefore must not be stored. The master secret and keys 1234 * should not be used directly except as an input to a key 1235 * derivation function. 1236 * 1237 * \param p_expkey Context for the callback 1238 * \param ms Pointer to master secret (fixed length: 48 bytes) 1239 * \param kb Pointer to key block, see RFC 5246 section 6.3 1240 * (variable length: 2 * maclen + 2 * keylen + 2 * ivlen). 1241 * \param maclen MAC length 1242 * \param keylen Key length 1243 * \param ivlen IV length 1244 * 1245 * \return 0 if successful, or 1246 * a specific MBEDTLS_ERR_XXX code. 1247 */ 1248 typedef int mbedtls_ssl_export_keys_t( void *p_expkey, 1249 const unsigned char *ms, 1250 const unsigned char *kb, 1251 size_t maclen, 1252 size_t keylen, 1253 size_t ivlen ); 1254 #endif /* MBEDTLS_SSL_EXPORT_KEYS */ 1255 1256 /** 1257 * \brief Callback type: parse and load session ticket 1258 * 1259 * \note This describes what a callback implementation should do. 1260 * This callback should parse a session ticket as generated 1261 * by the corresponding mbedtls_ssl_ticket_write_t function, 1262 * and, if the ticket is authentic and valid, load the 1263 * session. 1264 * 1265 * \note The implementation is allowed to modify the first len 1266 * bytes of the input buffer, eg to use it as a temporary 1267 * area for the decrypted ticket contents. 1268 * 1269 * \param p_ticket Context for the callback 1270 * \param session SSL session to be loaded 1271 * \param buf Start of the buffer containing the ticket 1272 * \param len Length of the ticket. 1273 * 1274 * \return 0 if successful, or 1275 * MBEDTLS_ERR_SSL_INVALID_MAC if not authentic, or 1276 * MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED if expired, or 1277 * any other non-zero code for other failures. 1278 */ 1279 typedef int mbedtls_ssl_ticket_parse_t( void *p_ticket, 1280 mbedtls_ssl_session *session, 1281 unsigned char *buf, 1282 size_t len ); 1283 1284 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C) 1285 /** 1286 * \brief Configure SSL session ticket callbacks (server only). 1287 * (Default: none.) 1288 * 1289 * \note On server, session tickets are enabled by providing 1290 * non-NULL callbacks. 1291 * 1292 * \note On client, use \c mbedtls_ssl_conf_session_tickets(). 1293 * 1294 * \param conf SSL configuration context 1295 * \param f_ticket_write Callback for writing a ticket 1296 * \param f_ticket_parse Callback for parsing a ticket 1297 * \param p_ticket Context shared by the two callbacks 1298 */ 1299 void mbedtls_ssl_conf_session_tickets_cb( mbedtls_ssl_config *conf, 1300 mbedtls_ssl_ticket_write_t *f_ticket_write, 1301 mbedtls_ssl_ticket_parse_t *f_ticket_parse, 1302 void *p_ticket ); 1303 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */ 1304 1305 #if defined(MBEDTLS_SSL_EXPORT_KEYS) 1306 /** 1307 * \brief Configure key export callback. 1308 * (Default: none.) 1309 * 1310 * \note See \c mbedtls_ssl_export_keys_t. 1311 * 1312 * \param conf SSL configuration context 1313 * \param f_export_keys Callback for exporting keys 1314 * \param p_export_keys Context for the callback 1315 */ 1316 void mbedtls_ssl_conf_export_keys_cb( mbedtls_ssl_config *conf, 1317 mbedtls_ssl_export_keys_t *f_export_keys, 1318 void *p_export_keys ); 1319 #endif /* MBEDTLS_SSL_EXPORT_KEYS */ 1320 1321 /** 1322 * \brief Callback type: generate a cookie 1323 * 1324 * \param ctx Context for the callback 1325 * \param p Buffer to write to, 1326 * must be updated to point right after the cookie 1327 * \param end Pointer to one past the end of the output buffer 1328 * \param info Client ID info that was passed to 1329 * \c mbedtls_ssl_set_client_transport_id() 1330 * \param ilen Length of info in bytes 1331 * 1332 * \return The callback must return 0 on success, 1333 * or a negative error code. 1334 */ 1335 typedef int mbedtls_ssl_cookie_write_t( void *ctx, 1336 unsigned char **p, unsigned char *end, 1337 const unsigned char *info, size_t ilen ); 1338 1339 /** 1340 * \brief Callback type: verify a cookie 1341 * 1342 * \param ctx Context for the callback 1343 * \param cookie Cookie to verify 1344 * \param clen Length of cookie 1345 * \param info Client ID info that was passed to 1346 * \c mbedtls_ssl_set_client_transport_id() 1347 * \param ilen Length of info in bytes 1348 * 1349 * \return The callback must return 0 if cookie is valid, 1350 * or a negative error code. 1351 */ 1352 typedef int mbedtls_ssl_cookie_check_t( void *ctx, 1353 const unsigned char *cookie, size_t clen, 1354 const unsigned char *info, size_t ilen ); 1355 1356 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) 1357 /** 1358 * \brief Register callbacks for DTLS cookies 1359 * (Server only. DTLS only.) 1360 * 1361 * Default: dummy callbacks that fail, in order to force you to 1362 * register working callbacks (and initialize their context). 1363 * 1364 * To disable HelloVerifyRequest, register NULL callbacks. 1365 * 1366 * \warning Disabling hello verification allows your server to be used 1367 * for amplification in DoS attacks against other hosts. 1368 * Only disable if you known this can't happen in your 1369 * particular environment. 1370 * 1371 * \note See comments on \c mbedtls_ssl_handshake() about handling 1372 * the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected 1373 * on the first handshake attempt when this is enabled. 1374 * 1375 * \note This is also necessary to handle client reconnection from 1376 * the same port as described in RFC 6347 section 4.2.8 (only 1377 * the variant with cookies is supported currently). See 1378 * comments on \c mbedtls_ssl_read() for details. 1379 * 1380 * \param conf SSL configuration 1381 * \param f_cookie_write Cookie write callback 1382 * \param f_cookie_check Cookie check callback 1383 * \param p_cookie Context for both callbacks 1384 */ 1385 void mbedtls_ssl_conf_dtls_cookies( mbedtls_ssl_config *conf, 1386 mbedtls_ssl_cookie_write_t *f_cookie_write, 1387 mbedtls_ssl_cookie_check_t *f_cookie_check, 1388 void *p_cookie ); 1389 1390 /** 1391 * \brief Set client's transport-level identification info. 1392 * (Server only. DTLS only.) 1393 * 1394 * This is usually the IP address (and port), but could be 1395 * anything identify the client depending on the underlying 1396 * network stack. Used for HelloVerifyRequest with DTLS. 1397 * This is *not* used to route the actual packets. 1398 * 1399 * \param ssl SSL context 1400 * \param info Transport-level info identifying the client (eg IP + port) 1401 * \param ilen Length of info in bytes 1402 * 1403 * \note An internal copy is made, so the info buffer can be reused. 1404 * 1405 * \return 0 on success, 1406 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client, 1407 * MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory. 1408 */ 1409 int mbedtls_ssl_set_client_transport_id( mbedtls_ssl_context *ssl, 1410 const unsigned char *info, 1411 size_t ilen ); 1412 1413 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */ 1414 1415 #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) 1416 /** 1417 * \brief Enable or disable anti-replay protection for DTLS. 1418 * (DTLS only, no effect on TLS.) 1419 * Default: enabled. 1420 * 1421 * \param conf SSL configuration 1422 * \param mode MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED. 1423 * 1424 * \warning Disabling this is a security risk unless the application 1425 * protocol handles duplicated packets in a safe way. You 1426 * should not disable this without careful consideration. 1427 * However, if your application already detects duplicated 1428 * packets and needs information about them to adjust its 1429 * transmission strategy, then you'll want to disable this. 1430 */ 1431 void mbedtls_ssl_conf_dtls_anti_replay( mbedtls_ssl_config *conf, char mode ); 1432 #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */ 1433 1434 #if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT) 1435 /** 1436 * \brief Set a limit on the number of records with a bad MAC 1437 * before terminating the connection. 1438 * (DTLS only, no effect on TLS.) 1439 * Default: 0 (disabled). 1440 * 1441 * \param conf SSL configuration 1442 * \param limit Limit, or 0 to disable. 1443 * 1444 * \note If the limit is N, then the connection is terminated when 1445 * the Nth non-authentic record is seen. 1446 * 1447 * \note Records with an invalid header are not counted, only the 1448 * ones going through the authentication-decryption phase. 1449 * 1450 * \note This is a security trade-off related to the fact that it's 1451 * often relatively easy for an active attacker ot inject UDP 1452 * datagrams. On one hand, setting a low limit here makes it 1453 * easier for such an attacker to forcibly terminated a 1454 * connection. On the other hand, a high limit or no limit 1455 * might make us waste resources checking authentication on 1456 * many bogus packets. 1457 */ 1458 void mbedtls_ssl_conf_dtls_badmac_limit( mbedtls_ssl_config *conf, unsigned limit ); 1459 #endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */ 1460 1461 #if defined(MBEDTLS_SSL_PROTO_DTLS) 1462 /** 1463 * \brief Set retransmit timeout values for the DTLS handshake. 1464 * (DTLS only, no effect on TLS.) 1465 * 1466 * \param conf SSL configuration 1467 * \param min Initial timeout value in milliseconds. 1468 * Default: 1000 (1 second). 1469 * \param max Maximum timeout value in milliseconds. 1470 * Default: 60000 (60 seconds). 1471 * 1472 * \note Default values are from RFC 6347 section 4.2.4.1. 1473 * 1474 * \note The 'min' value should typically be slightly above the 1475 * expected round-trip time to your peer, plus whatever time 1476 * it takes for the peer to process the message. For example, 1477 * if your RTT is about 600ms and you peer needs up to 1s to 1478 * do the cryptographic operations in the handshake, then you 1479 * should set 'min' slightly above 1600. Lower values of 'min' 1480 * might cause spurious resends which waste network resources, 1481 * while larger value of 'min' will increase overall latency 1482 * on unreliable network links. 1483 * 1484 * \note The more unreliable your network connection is, the larger 1485 * your max / min ratio needs to be in order to achieve 1486 * reliable handshakes. 1487 * 1488 * \note Messages are retransmitted up to log2(ceil(max/min)) times. 1489 * For example, if min = 1s and max = 5s, the retransmit plan 1490 * goes: send ... 1s -> resend ... 2s -> resend ... 4s -> 1491 * resend ... 5s -> give up and return a timeout error. 1492 */ 1493 void mbedtls_ssl_conf_handshake_timeout( mbedtls_ssl_config *conf, uint32_t min, uint32_t max ); 1494 #endif /* MBEDTLS_SSL_PROTO_DTLS */ 1495 1496 #if defined(MBEDTLS_SSL_SRV_C) 1497 /** 1498 * \brief Set the session cache callbacks (server-side only) 1499 * If not set, no session resuming is done (except if session 1500 * tickets are enabled too). 1501 * 1502 * The session cache has the responsibility to check for stale 1503 * entries based on timeout. See RFC 5246 for recommendations. 1504 * 1505 * Warning: session.peer_cert is cleared by the SSL/TLS layer on 1506 * connection shutdown, so do not cache the pointer! Either set 1507 * it to NULL or make a full copy of the certificate. 1508 * 1509 * The get callback is called once during the initial handshake 1510 * to enable session resuming. The get function has the 1511 * following parameters: (void *parameter, mbedtls_ssl_session *session) 1512 * If a valid entry is found, it should fill the master of 1513 * the session object with the cached values and return 0, 1514 * return 1 otherwise. Optionally peer_cert can be set as well 1515 * if it is properly present in cache entry. 1516 * 1517 * The set callback is called once during the initial handshake 1518 * to enable session resuming after the entire handshake has 1519 * been finished. The set function has the following parameters: 1520 * (void *parameter, const mbedtls_ssl_session *session). The function 1521 * should create a cache entry for future retrieval based on 1522 * the data in the session structure and should keep in mind 1523 * that the mbedtls_ssl_session object presented (and all its referenced 1524 * data) is cleared by the SSL/TLS layer when the connection is 1525 * terminated. It is recommended to add metadata to determine if 1526 * an entry is still valid in the future. Return 0 if 1527 * successfully cached, return 1 otherwise. 1528 * 1529 * \param conf SSL configuration 1530 * \param p_cache parmater (context) for both callbacks 1531 * \param f_get_cache session get callback 1532 * \param f_set_cache session set callback 1533 */ 1534 void mbedtls_ssl_conf_session_cache( mbedtls_ssl_config *conf, 1535 void *p_cache, 1536 int (*f_get_cache)(void *, mbedtls_ssl_session *), 1537 int (*f_set_cache)(void *, const mbedtls_ssl_session *) ); 1538 #endif /* MBEDTLS_SSL_SRV_C */ 1539 1540 #if defined(MBEDTLS_SSL_CLI_C) 1541 /** 1542 * \brief Request resumption of session (client-side only) 1543 * Session data is copied from presented session structure. 1544 * 1545 * \param ssl SSL context 1546 * \param session session context 1547 * 1548 * \return 0 if successful, 1549 * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed, 1550 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or 1551 * arguments are otherwise invalid 1552 * 1553 * \sa mbedtls_ssl_get_session() 1554 */ 1555 int mbedtls_ssl_set_session( mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session ); 1556 #endif /* MBEDTLS_SSL_CLI_C */ 1557 1558 /** 1559 * \brief Set the list of allowed ciphersuites and the preference 1560 * order. First in the list has the highest preference. 1561 * (Overrides all version-specific lists) 1562 * 1563 * The ciphersuites array is not copied, and must remain 1564 * valid for the lifetime of the ssl_config. 1565 * 1566 * Note: The server uses its own preferences 1567 * over the preference of the client unless 1568 * MBEDTLS_SSL_SRV_RESPECT_CLIENT_PREFERENCE is defined! 1569 * 1570 * \param conf SSL configuration 1571 * \param ciphersuites 0-terminated list of allowed ciphersuites 1572 */ 1573 void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf, 1574 const int *ciphersuites ); 1575 1576 /** 1577 * \brief Set the list of allowed ciphersuites and the 1578 * preference order for a specific version of the protocol. 1579 * (Only useful on the server side) 1580 * 1581 * The ciphersuites array is not copied, and must remain 1582 * valid for the lifetime of the ssl_config. 1583 * 1584 * \param conf SSL configuration 1585 * \param ciphersuites 0-terminated list of allowed ciphersuites 1586 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 1587 * supported) 1588 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0, 1589 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2, 1590 * MBEDTLS_SSL_MINOR_VERSION_3 supported) 1591 * 1592 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 1593 * and MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2 1594 */ 1595 void mbedtls_ssl_conf_ciphersuites_for_version( mbedtls_ssl_config *conf, 1596 const int *ciphersuites, 1597 int major, int minor ); 1598 1599 #if defined(MBEDTLS_X509_CRT_PARSE_C) 1600 /** 1601 * \brief Set the X.509 security profile used for verification 1602 * 1603 * \note The restrictions are enforced for all certificates in the 1604 * chain. However, signatures in the handshake are not covered 1605 * by this setting but by \b mbedtls_ssl_conf_sig_hashes(). 1606 * 1607 * \param conf SSL configuration 1608 * \param profile Profile to use 1609 */ 1610 void mbedtls_ssl_conf_cert_profile( mbedtls_ssl_config *conf, 1611 const mbedtls_x509_crt_profile *profile ); 1612 1613 /** 1614 * \brief Set the data required to verify peer certificate 1615 * 1616 * \note See \c mbedtls_x509_crt_verify() for notes regarding the 1617 * parameters ca_chain (maps to trust_ca for that function) 1618 * and ca_crl. 1619 * 1620 * \param conf SSL configuration 1621 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs) 1622 * \param ca_crl trusted CA CRLs 1623 */ 1624 void mbedtls_ssl_conf_ca_chain( mbedtls_ssl_config *conf, 1625 mbedtls_x509_crt *ca_chain, 1626 mbedtls_x509_crl *ca_crl ); 1627 1628 /** 1629 * \brief Set own certificate chain and private key 1630 * 1631 * \note own_cert should contain in order from the bottom up your 1632 * certificate chain. The top certificate (self-signed) 1633 * can be omitted. 1634 * 1635 * \note On server, this function can be called multiple times to 1636 * provision more than one cert/key pair (eg one ECDSA, one 1637 * RSA with SHA-256, one RSA with SHA-1). An adequate 1638 * certificate will be selected according to the client's 1639 * advertised capabilities. In case multiple certificates are 1640 * adequate, preference is given to the one set by the first 1641 * call to this function, then second, etc. 1642 * 1643 * \note On client, only the first call has any effect. That is, 1644 * only one client certificate can be provisioned. The 1645 * server's preferences in its CertficateRequest message will 1646 * be ignored and our only cert will be sent regardless of 1647 * whether it matches those preferences - the server can then 1648 * decide what it wants to do with it. 1649 * 1650 * \note The provided \p pk_key needs to match the public key in the 1651 * first certificate in \p own_cert, or all handshakes using 1652 * that certificate will fail. It is your responsibility 1653 * to ensure that; this function will not perform any check. 1654 * You may use mbedtls_pk_check_pair() in order to perform 1655 * this check yourself, but be aware that this function can 1656 * be computationally expensive on some key types. 1657 * 1658 * \param conf SSL configuration 1659 * \param own_cert own public certificate chain 1660 * \param pk_key own private key 1661 * 1662 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED 1663 */ 1664 int mbedtls_ssl_conf_own_cert( mbedtls_ssl_config *conf, 1665 mbedtls_x509_crt *own_cert, 1666 mbedtls_pk_context *pk_key ); 1667 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 1668 1669 #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED) 1670 /** 1671 * \brief Set the Pre Shared Key (PSK) and the expected identity name 1672 * 1673 * \note This is mainly useful for clients. Servers will usually 1674 * want to use \c mbedtls_ssl_conf_psk_cb() instead. 1675 * 1676 * \note Currently clients can only register one pre-shared key. 1677 * In other words, the servers' identity hint is ignored. 1678 * Support for setting multiple PSKs on clients and selecting 1679 * one based on the identity hint is not a planned feature but 1680 * feedback is welcomed. 1681 * 1682 * \param conf SSL configuration 1683 * \param psk pointer to the pre-shared key 1684 * \param psk_len pre-shared key length 1685 * \param psk_identity pointer to the pre-shared key identity 1686 * \param psk_identity_len identity key length 1687 * 1688 * \return 0 if successful or MBEDTLS_ERR_SSL_ALLOC_FAILED 1689 */ 1690 int mbedtls_ssl_conf_psk( mbedtls_ssl_config *conf, 1691 const unsigned char *psk, size_t psk_len, 1692 const unsigned char *psk_identity, size_t psk_identity_len ); 1693 1694 1695 /** 1696 * \brief Set the Pre Shared Key (PSK) for the current handshake 1697 * 1698 * \note This should only be called inside the PSK callback, 1699 * ie the function passed to \c mbedtls_ssl_conf_psk_cb(). 1700 * 1701 * \param ssl SSL context 1702 * \param psk pointer to the pre-shared key 1703 * \param psk_len pre-shared key length 1704 * 1705 * \return 0 if successful or MBEDTLS_ERR_SSL_ALLOC_FAILED 1706 */ 1707 int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl, 1708 const unsigned char *psk, size_t psk_len ); 1709 1710 /** 1711 * \brief Set the PSK callback (server-side only). 1712 * 1713 * If set, the PSK callback is called for each 1714 * handshake where a PSK ciphersuite was negotiated. 1715 * The caller provides the identity received and wants to 1716 * receive the actual PSK data and length. 1717 * 1718 * The callback has the following parameters: (void *parameter, 1719 * mbedtls_ssl_context *ssl, const unsigned char *psk_identity, 1720 * size_t identity_len) 1721 * If a valid PSK identity is found, the callback should use 1722 * \c mbedtls_ssl_set_hs_psk() on the ssl context to set the 1723 * correct PSK and return 0. 1724 * Any other return value will result in a denied PSK identity. 1725 * 1726 * \note If you set a PSK callback using this function, then you 1727 * don't need to set a PSK key and identity using 1728 * \c mbedtls_ssl_conf_psk(). 1729 * 1730 * \param conf SSL configuration 1731 * \param f_psk PSK identity function 1732 * \param p_psk PSK identity parameter 1733 */ 1734 void mbedtls_ssl_conf_psk_cb( mbedtls_ssl_config *conf, 1735 int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, 1736 size_t), 1737 void *p_psk ); 1738 #endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */ 1739 1740 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C) 1741 1742 #if !defined(MBEDTLS_DEPRECATED_REMOVED) 1743 1744 #if defined(MBEDTLS_DEPRECATED_WARNING) 1745 #define MBEDTLS_DEPRECATED __attribute__((deprecated)) 1746 #else 1747 #define MBEDTLS_DEPRECATED 1748 #endif 1749 1750 /** 1751 * \brief Set the Diffie-Hellman public P and G values, 1752 * read as hexadecimal strings (server-side only) 1753 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]) 1754 * 1755 * \param conf SSL configuration 1756 * \param dhm_P Diffie-Hellman-Merkle modulus 1757 * \param dhm_G Diffie-Hellman-Merkle generator 1758 * 1759 * \deprecated Superseded by \c mbedtls_ssl_conf_dh_param_bin. 1760 * 1761 * \return 0 if successful 1762 */ 1763 MBEDTLS_DEPRECATED int mbedtls_ssl_conf_dh_param( mbedtls_ssl_config *conf, 1764 const char *dhm_P, 1765 const char *dhm_G ); 1766 1767 #endif /* MBEDTLS_DEPRECATED_REMOVED */ 1768 1769 /** 1770 * \brief Set the Diffie-Hellman public P and G values 1771 * from big-endian binary presentations. 1772 * (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN) 1773 * 1774 * \param conf SSL configuration 1775 * \param dhm_P Diffie-Hellman-Merkle modulus in big-endian binary form 1776 * \param P_len Length of DHM modulus 1777 * \param dhm_G Diffie-Hellman-Merkle generator in big-endian binary form 1778 * \param G_len Length of DHM generator 1779 * 1780 * \return 0 if successful 1781 */ 1782 int mbedtls_ssl_conf_dh_param_bin( mbedtls_ssl_config *conf, 1783 const unsigned char *dhm_P, size_t P_len, 1784 const unsigned char *dhm_G, size_t G_len ); 1785 1786 /** 1787 * \brief Set the Diffie-Hellman public P and G values, 1788 * read from existing context (server-side only) 1789 * 1790 * \param conf SSL configuration 1791 * \param dhm_ctx Diffie-Hellman-Merkle context 1792 * 1793 * \return 0 if successful 1794 */ 1795 int mbedtls_ssl_conf_dh_param_ctx( mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx ); 1796 #endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */ 1797 1798 #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C) 1799 /** 1800 * \brief Set the minimum length for Diffie-Hellman parameters. 1801 * (Client-side only.) 1802 * (Default: 1024 bits.) 1803 * 1804 * \param conf SSL configuration 1805 * \param bitlen Minimum bit length of the DHM prime 1806 */ 1807 void mbedtls_ssl_conf_dhm_min_bitlen( mbedtls_ssl_config *conf, 1808 unsigned int bitlen ); 1809 #endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */ 1810 1811 #if defined(MBEDTLS_ECP_C) 1812 /** 1813 * \brief Set the allowed curves in order of preference. 1814 * (Default: all defined curves.) 1815 * 1816 * On server: this only affects selection of the ECDHE curve; 1817 * the curves used for ECDH and ECDSA are determined by the 1818 * list of available certificates instead. 1819 * 1820 * On client: this affects the list of curves offered for any 1821 * use. The server can override our preference order. 1822 * 1823 * Both sides: limits the set of curves accepted for use in 1824 * ECDHE and in the peer's end-entity certificate. 1825 * 1826 * \note This has no influence on which curves are allowed inside the 1827 * certificate chains, see \c mbedtls_ssl_conf_cert_profile() 1828 * for that. For the end-entity certificate however, the key 1829 * will be accepted only if it is allowed both by this list 1830 * and by the cert profile. 1831 * 1832 * \note This list should be ordered by decreasing preference 1833 * (preferred curve first). 1834 * 1835 * \param conf SSL configuration 1836 * \param curves Ordered list of allowed curves, 1837 * terminated by MBEDTLS_ECP_DP_NONE. 1838 */ 1839 void mbedtls_ssl_conf_curves( mbedtls_ssl_config *conf, 1840 const mbedtls_ecp_group_id *curves ); 1841 #endif /* MBEDTLS_ECP_C */ 1842 1843 #if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) 1844 /** 1845 * \brief Set the allowed hashes for signatures during the handshake. 1846 * (Default: all available hashes except MD5.) 1847 * 1848 * \note This only affects which hashes are offered and can be used 1849 * for signatures during the handshake. Hashes for message 1850 * authentication and the TLS PRF are controlled by the 1851 * ciphersuite, see \c mbedtls_ssl_conf_ciphersuites(). Hashes 1852 * used for certificate signature are controlled by the 1853 * verification profile, see \c mbedtls_ssl_conf_cert_profile(). 1854 * 1855 * \note This list should be ordered by decreasing preference 1856 * (preferred hash first). 1857 * 1858 * \param conf SSL configuration 1859 * \param hashes Ordered list of allowed signature hashes, 1860 * terminated by \c MBEDTLS_MD_NONE. 1861 */ 1862 void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf, 1863 const int *hashes ); 1864 #endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */ 1865 1866 #if defined(MBEDTLS_X509_CRT_PARSE_C) 1867 /** 1868 * \brief Set or reset the hostname to check against the received 1869 * server certificate. It sets the ServerName TLS extension, 1870 * too, if that extension is enabled. (client-side only) 1871 * 1872 * \param ssl SSL context 1873 * \param hostname the server hostname, may be NULL to clear hostname 1874 * 1875 * \note Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN. 1876 * 1877 * \return 0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on 1878 * allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on 1879 * too long input hostname. 1880 * 1881 * Hostname set to the one provided on success (cleared 1882 * when NULL). On allocation failure hostname is cleared. 1883 * On too long input failure, old hostname is unchanged. 1884 */ 1885 int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname ); 1886 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 1887 1888 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) 1889 /** 1890 * \brief Set own certificate and key for the current handshake 1891 * 1892 * \note Same as \c mbedtls_ssl_conf_own_cert() but for use within 1893 * the SNI callback. 1894 * 1895 * \param ssl SSL context 1896 * \param own_cert own public certificate chain 1897 * \param pk_key own private key 1898 * 1899 * \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED 1900 */ 1901 int mbedtls_ssl_set_hs_own_cert( mbedtls_ssl_context *ssl, 1902 mbedtls_x509_crt *own_cert, 1903 mbedtls_pk_context *pk_key ); 1904 1905 /** 1906 * \brief Set the data required to verify peer certificate for the 1907 * current handshake 1908 * 1909 * \note Same as \c mbedtls_ssl_conf_ca_chain() but for use within 1910 * the SNI callback. 1911 * 1912 * \param ssl SSL context 1913 * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs) 1914 * \param ca_crl trusted CA CRLs 1915 */ 1916 void mbedtls_ssl_set_hs_ca_chain( mbedtls_ssl_context *ssl, 1917 mbedtls_x509_crt *ca_chain, 1918 mbedtls_x509_crl *ca_crl ); 1919 1920 /** 1921 * \brief Set authmode for the current handshake. 1922 * 1923 * \note Same as \c mbedtls_ssl_conf_authmode() but for use within 1924 * the SNI callback. 1925 * 1926 * \param ssl SSL context 1927 * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or 1928 * MBEDTLS_SSL_VERIFY_REQUIRED 1929 */ 1930 void mbedtls_ssl_set_hs_authmode( mbedtls_ssl_context *ssl, 1931 int authmode ); 1932 1933 /** 1934 * \brief Set server side ServerName TLS extension callback 1935 * (optional, server-side only). 1936 * 1937 * If set, the ServerName callback is called whenever the 1938 * server receives a ServerName TLS extension from the client 1939 * during a handshake. The ServerName callback has the 1940 * following parameters: (void *parameter, mbedtls_ssl_context *ssl, 1941 * const unsigned char *hostname, size_t len). If a suitable 1942 * certificate is found, the callback must set the 1943 * certificate(s) and key(s) to use with \c 1944 * mbedtls_ssl_set_hs_own_cert() (can be called repeatedly), 1945 * and may optionally adjust the CA and associated CRL with \c 1946 * mbedtls_ssl_set_hs_ca_chain() as well as the client 1947 * authentication mode with \c mbedtls_ssl_set_hs_authmode(), 1948 * then must return 0. If no matching name is found, the 1949 * callback must either set a default cert, or 1950 * return non-zero to abort the handshake at this point. 1951 * 1952 * \param conf SSL configuration 1953 * \param f_sni verification function 1954 * \param p_sni verification parameter 1955 */ 1956 void mbedtls_ssl_conf_sni( mbedtls_ssl_config *conf, 1957 int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, 1958 size_t), 1959 void *p_sni ); 1960 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */ 1961 1962 #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) 1963 /** 1964 * \brief Set the EC J-PAKE password for current handshake. 1965 * 1966 * \note An internal copy is made, and destroyed as soon as the 1967 * handshake is completed, or when the SSL context is reset or 1968 * freed. 1969 * 1970 * \note The SSL context needs to be already set up. The right place 1971 * to call this function is between \c mbedtls_ssl_setup() or 1972 * \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake(). 1973 * 1974 * \param ssl SSL context 1975 * \param pw EC J-PAKE password (pre-shared secret) 1976 * \param pw_len length of pw in bytes 1977 * 1978 * \return 0 on success, or a negative error code. 1979 */ 1980 int mbedtls_ssl_set_hs_ecjpake_password( mbedtls_ssl_context *ssl, 1981 const unsigned char *pw, 1982 size_t pw_len ); 1983 #endif /*MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ 1984 1985 #if defined(MBEDTLS_SSL_ALPN) 1986 /** 1987 * \brief Set the supported Application Layer Protocols. 1988 * 1989 * \param conf SSL configuration 1990 * \param protos Pointer to a NULL-terminated list of supported protocols, 1991 * in decreasing preference order. The pointer to the list is 1992 * recorded by the library for later reference as required, so 1993 * the lifetime of the table must be atleast as long as the 1994 * lifetime of the SSL configuration structure. 1995 * 1996 * \return 0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA. 1997 */ 1998 int mbedtls_ssl_conf_alpn_protocols( mbedtls_ssl_config *conf, const char **protos ); 1999 2000 /** 2001 * \brief Get the name of the negotiated Application Layer Protocol. 2002 * This function should be called after the handshake is 2003 * completed. 2004 * 2005 * \param ssl SSL context 2006 * 2007 * \return Protcol name, or NULL if no protocol was negotiated. 2008 */ 2009 const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl ); 2010 #endif /* MBEDTLS_SSL_ALPN */ 2011 2012 /** 2013 * \brief Set the maximum supported version sent from the client side 2014 * and/or accepted at the server side 2015 * (Default: MBEDTLS_SSL_MAX_MAJOR_VERSION, MBEDTLS_SSL_MAX_MINOR_VERSION) 2016 * 2017 * \note This ignores ciphersuites from higher versions. 2018 * 2019 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and 2020 * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2 2021 * 2022 * \param conf SSL configuration 2023 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported) 2024 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0, 2025 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2, 2026 * MBEDTLS_SSL_MINOR_VERSION_3 supported) 2027 */ 2028 void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor ); 2029 2030 /** 2031 * \brief Set the minimum accepted SSL/TLS protocol version 2032 * (Default: TLS 1.0) 2033 * 2034 * \note Input outside of the SSL_MAX_XXXXX_VERSION and 2035 * SSL_MIN_XXXXX_VERSION range is ignored. 2036 * 2037 * \note MBEDTLS_SSL_MINOR_VERSION_0 (SSL v3) should be avoided. 2038 * 2039 * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and 2040 * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2 2041 * 2042 * \param conf SSL configuration 2043 * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported) 2044 * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0, 2045 * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2, 2046 * MBEDTLS_SSL_MINOR_VERSION_3 supported) 2047 */ 2048 void mbedtls_ssl_conf_min_version( mbedtls_ssl_config *conf, int major, int minor ); 2049 2050 #if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C) 2051 /** 2052 * \brief Set the fallback flag (client-side only). 2053 * (Default: MBEDTLS_SSL_IS_NOT_FALLBACK). 2054 * 2055 * \note Set to MBEDTLS_SSL_IS_FALLBACK when preparing a fallback 2056 * connection, that is a connection with max_version set to a 2057 * lower value than the value you're willing to use. Such 2058 * fallback connections are not recommended but are sometimes 2059 * necessary to interoperate with buggy (version-intolerant) 2060 * servers. 2061 * 2062 * \warning You should NOT set this to MBEDTLS_SSL_IS_FALLBACK for 2063 * non-fallback connections! This would appear to work for a 2064 * while, then cause failures when the server is upgraded to 2065 * support a newer TLS version. 2066 * 2067 * \param conf SSL configuration 2068 * \param fallback MBEDTLS_SSL_IS_NOT_FALLBACK or MBEDTLS_SSL_IS_FALLBACK 2069 */ 2070 void mbedtls_ssl_conf_fallback( mbedtls_ssl_config *conf, char fallback ); 2071 #endif /* MBEDTLS_SSL_FALLBACK_SCSV && MBEDTLS_SSL_CLI_C */ 2072 2073 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) 2074 /** 2075 * \brief Enable or disable Encrypt-then-MAC 2076 * (Default: MBEDTLS_SSL_ETM_ENABLED) 2077 * 2078 * \note This should always be enabled, it is a security 2079 * improvement, and should not cause any interoperability 2080 * issue (used only if the peer supports it too). 2081 * 2082 * \param conf SSL configuration 2083 * \param etm MBEDTLS_SSL_ETM_ENABLED or MBEDTLS_SSL_ETM_DISABLED 2084 */ 2085 void mbedtls_ssl_conf_encrypt_then_mac( mbedtls_ssl_config *conf, char etm ); 2086 #endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */ 2087 2088 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) 2089 /** 2090 * \brief Enable or disable Extended Master Secret negotiation. 2091 * (Default: MBEDTLS_SSL_EXTENDED_MS_ENABLED) 2092 * 2093 * \note This should always be enabled, it is a security fix to the 2094 * protocol, and should not cause any interoperability issue 2095 * (used only if the peer supports it too). 2096 * 2097 * \param conf SSL configuration 2098 * \param ems MBEDTLS_SSL_EXTENDED_MS_ENABLED or MBEDTLS_SSL_EXTENDED_MS_DISABLED 2099 */ 2100 void mbedtls_ssl_conf_extended_master_secret( mbedtls_ssl_config *conf, char ems ); 2101 #endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */ 2102 2103 #if defined(MBEDTLS_ARC4_C) 2104 /** 2105 * \brief Disable or enable support for RC4 2106 * (Default: MBEDTLS_SSL_ARC4_DISABLED) 2107 * 2108 * \warning Use of RC4 in DTLS/TLS has been prohibited by RFC 7465 2109 * for security reasons. Use at your own risk. 2110 * 2111 * \note This function is deprecated and will likely be removed in 2112 * a future version of the library. 2113 * RC4 is disabled by default at compile time and needs to be 2114 * actively enabled for use with legacy systems. 2115 * 2116 * \param conf SSL configuration 2117 * \param arc4 MBEDTLS_SSL_ARC4_ENABLED or MBEDTLS_SSL_ARC4_DISABLED 2118 */ 2119 void mbedtls_ssl_conf_arc4_support( mbedtls_ssl_config *conf, char arc4 ); 2120 #endif /* MBEDTLS_ARC4_C */ 2121 2122 #if defined(MBEDTLS_SSL_SRV_C) 2123 /** 2124 * \brief Whether to send a list of acceptable CAs in 2125 * CertificateRequest messages. 2126 * (Default: do send) 2127 * 2128 * \param conf SSL configuration 2129 * \param cert_req_ca_list MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or 2130 * MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED 2131 */ 2132 void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf, 2133 char cert_req_ca_list ); 2134 #endif /* MBEDTLS_SSL_SRV_C */ 2135 2136 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) 2137 /** 2138 * \brief Set the maximum fragment length to emit and/or negotiate. 2139 * (Typical: #MBEDTLS_SSL_MAX_CONTENT_LEN, by default that is 2140 * set to `2^14` bytes) 2141 * (Server: set maximum fragment length to emit, 2142 * usually negotiated by the client during handshake) 2143 * (Client: set maximum fragment length to emit *and* 2144 * negotiate with the server during handshake) 2145 * (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE) 2146 * 2147 * \note With TLS, this currently only affects ApplicationData (sent 2148 * with \c mbedtls_ssl_read()), not handshake messages. 2149 * With DTLS, this affects both ApplicationData and handshake. 2150 * 2151 * \note On the client side, the maximum fragment length extension 2152 * *will not* be used, unless the maximum fragment length has 2153 * been set via this function to a value different than 2154 * #MBEDTLS_SSL_MAX_FRAG_LEN_NONE. 2155 * 2156 * \note This sets the maximum length for a record's payload, 2157 * excluding record overhead that will be added to it, see 2158 * \c mbedtls_ssl_get_record_expansion(). 2159 * 2160 * \param conf SSL configuration 2161 * \param mfl_code Code for maximum fragment length (allowed values: 2162 * MBEDTLS_SSL_MAX_FRAG_LEN_512, MBEDTLS_SSL_MAX_FRAG_LEN_1024, 2163 * MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096) 2164 * 2165 * \return 0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA 2166 */ 2167 int mbedtls_ssl_conf_max_frag_len( mbedtls_ssl_config *conf, unsigned char mfl_code ); 2168 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ 2169 2170 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC) 2171 /** 2172 * \brief Activate negotiation of truncated HMAC 2173 * (Default: MBEDTLS_SSL_TRUNC_HMAC_DISABLED) 2174 * 2175 * \param conf SSL configuration 2176 * \param truncate Enable or disable (MBEDTLS_SSL_TRUNC_HMAC_ENABLED or 2177 * MBEDTLS_SSL_TRUNC_HMAC_DISABLED) 2178 */ 2179 void mbedtls_ssl_conf_truncated_hmac( mbedtls_ssl_config *conf, int truncate ); 2180 #endif /* MBEDTLS_SSL_TRUNCATED_HMAC */ 2181 2182 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING) 2183 /** 2184 * \brief Enable / Disable 1/n-1 record splitting 2185 * (Default: MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED) 2186 * 2187 * \note Only affects SSLv3 and TLS 1.0, not higher versions. 2188 * Does not affect non-CBC ciphersuites in any version. 2189 * 2190 * \param conf SSL configuration 2191 * \param split MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED or 2192 * MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED 2193 */ 2194 void mbedtls_ssl_conf_cbc_record_splitting( mbedtls_ssl_config *conf, char split ); 2195 #endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */ 2196 2197 #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C) 2198 /** 2199 * \brief Enable / Disable session tickets (client only). 2200 * (Default: MBEDTLS_SSL_SESSION_TICKETS_ENABLED.) 2201 * 2202 * \note On server, use \c mbedtls_ssl_conf_session_tickets_cb(). 2203 * 2204 * \param conf SSL configuration 2205 * \param use_tickets Enable or disable (MBEDTLS_SSL_SESSION_TICKETS_ENABLED or 2206 * MBEDTLS_SSL_SESSION_TICKETS_DISABLED) 2207 */ 2208 void mbedtls_ssl_conf_session_tickets( mbedtls_ssl_config *conf, int use_tickets ); 2209 #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */ 2210 2211 #if defined(MBEDTLS_SSL_RENEGOTIATION) 2212 /** 2213 * \brief Enable / Disable renegotiation support for connection when 2214 * initiated by peer 2215 * (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED) 2216 * 2217 * \warning It is recommended to always disable renegotation unless you 2218 * know you need it and you know what you're doing. In the 2219 * past, there have been several issues associated with 2220 * renegotiation or a poor understanding of its properties. 2221 * 2222 * \note Server-side, enabling renegotiation also makes the server 2223 * susceptible to a resource DoS by a malicious client. 2224 * 2225 * \param conf SSL configuration 2226 * \param renegotiation Enable or disable (MBEDTLS_SSL_RENEGOTIATION_ENABLED or 2227 * MBEDTLS_SSL_RENEGOTIATION_DISABLED) 2228 */ 2229 void mbedtls_ssl_conf_renegotiation( mbedtls_ssl_config *conf, int renegotiation ); 2230 #endif /* MBEDTLS_SSL_RENEGOTIATION */ 2231 2232 /** 2233 * \brief Prevent or allow legacy renegotiation. 2234 * (Default: MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION) 2235 * 2236 * MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION allows connections to 2237 * be established even if the peer does not support 2238 * secure renegotiation, but does not allow renegotiation 2239 * to take place if not secure. 2240 * (Interoperable and secure option) 2241 * 2242 * MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION allows renegotiations 2243 * with non-upgraded peers. Allowing legacy renegotiation 2244 * makes the connection vulnerable to specific man in the 2245 * middle attacks. (See RFC 5746) 2246 * (Most interoperable and least secure option) 2247 * 2248 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE breaks off connections 2249 * if peer does not support secure renegotiation. Results 2250 * in interoperability issues with non-upgraded peers 2251 * that do not support renegotiation altogether. 2252 * (Most secure option, interoperability issues) 2253 * 2254 * \param conf SSL configuration 2255 * \param allow_legacy Prevent or allow (SSL_NO_LEGACY_RENEGOTIATION, 2256 * SSL_ALLOW_LEGACY_RENEGOTIATION or 2257 * MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE) 2258 */ 2259 void mbedtls_ssl_conf_legacy_renegotiation( mbedtls_ssl_config *conf, int allow_legacy ); 2260 2261 #if defined(MBEDTLS_SSL_RENEGOTIATION) 2262 /** 2263 * \brief Enforce renegotiation requests. 2264 * (Default: enforced, max_records = 16) 2265 * 2266 * When we request a renegotiation, the peer can comply or 2267 * ignore the request. This function allows us to decide 2268 * whether to enforce our renegotiation requests by closing 2269 * the connection if the peer doesn't comply. 2270 * 2271 * However, records could already be in transit from the peer 2272 * when the request is emitted. In order to increase 2273 * reliability, we can accept a number of records before the 2274 * expected handshake records. 2275 * 2276 * The optimal value is highly dependent on the specific usage 2277 * scenario. 2278 * 2279 * \note With DTLS and server-initiated renegotiation, the 2280 * HelloRequest is retransmited every time mbedtls_ssl_read() times 2281 * out or receives Application Data, until: 2282 * - max_records records have beens seen, if it is >= 0, or 2283 * - the number of retransmits that would happen during an 2284 * actual handshake has been reached. 2285 * Please remember the request might be lost a few times 2286 * if you consider setting max_records to a really low value. 2287 * 2288 * \warning On client, the grace period can only happen during 2289 * mbedtls_ssl_read(), as opposed to mbedtls_ssl_write() and mbedtls_ssl_renegotiate() 2290 * which always behave as if max_record was 0. The reason is, 2291 * if we receive application data from the server, we need a 2292 * place to write it, which only happens during mbedtls_ssl_read(). 2293 * 2294 * \param conf SSL configuration 2295 * \param max_records Use MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to 2296 * enforce renegotiation, or a non-negative value to enforce 2297 * it but allow for a grace period of max_records records. 2298 */ 2299 void mbedtls_ssl_conf_renegotiation_enforced( mbedtls_ssl_config *conf, int max_records ); 2300 2301 /** 2302 * \brief Set record counter threshold for periodic renegotiation. 2303 * (Default: 2^48 - 1) 2304 * 2305 * Renegotiation is automatically triggered when a record 2306 * counter (outgoing or ingoing) crosses the defined 2307 * threshold. The default value is meant to prevent the 2308 * connection from being closed when the counter is about to 2309 * reached its maximal value (it is not allowed to wrap). 2310 * 2311 * Lower values can be used to enforce policies such as "keys 2312 * must be refreshed every N packets with cipher X". 2313 * 2314 * The renegotiation period can be disabled by setting 2315 * conf->disable_renegotiation to 2316 * MBEDTLS_SSL_RENEGOTIATION_DISABLED. 2317 * 2318 * \note When the configured transport is 2319 * MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation 2320 * period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM, 2321 * the maximum renegotiation period is 2^64 - 1. 2322 * 2323 * \param conf SSL configuration 2324 * \param period The threshold value: a big-endian 64-bit number. 2325 */ 2326 void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf, 2327 const unsigned char period[8] ); 2328 #endif /* MBEDTLS_SSL_RENEGOTIATION */ 2329 2330 /** 2331 * \brief Return the number of data bytes available to read 2332 * 2333 * \param ssl SSL context 2334 * 2335 * \return how many bytes are available in the read buffer 2336 */ 2337 size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl ); 2338 2339 /** 2340 * \brief Return the result of the certificate verification 2341 * 2342 * \param ssl The SSL context to use. 2343 * 2344 * \return \c 0 if the certificate verification was successful. 2345 * \return \c -1u if the result is not available. This may happen 2346 * e.g. if the handshake aborts early, or a verification 2347 * callback returned a fatal error. 2348 * \return A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX 2349 * and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h. 2350 */ 2351 uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl ); 2352 2353 /** 2354 * \brief Return the name of the current ciphersuite 2355 * 2356 * \param ssl SSL context 2357 * 2358 * \return a string containing the ciphersuite name 2359 */ 2360 const char *mbedtls_ssl_get_ciphersuite( const mbedtls_ssl_context *ssl ); 2361 2362 /** 2363 * \brief Return the current SSL version (SSLv3/TLSv1/etc) 2364 * 2365 * \param ssl SSL context 2366 * 2367 * \return a string containing the SSL version 2368 */ 2369 const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl ); 2370 2371 /** 2372 * \brief Return the (maximum) number of bytes added by the record 2373 * layer: header + encryption/MAC overhead (inc. padding) 2374 * 2375 * \param ssl SSL context 2376 * 2377 * \return Current maximum record expansion in bytes, or 2378 * MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if compression is 2379 * enabled, which makes expansion much less predictable 2380 */ 2381 int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl ); 2382 2383 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) 2384 /** 2385 * \brief Return the maximum fragment length (payload, in bytes). 2386 * This is the value negotiated with peer if any, 2387 * or the locally configured value. 2388 * 2389 * \note With DTLS, \c mbedtls_ssl_write() will return an error if 2390 * called with a larger length value. 2391 * With TLS, \c mbedtls_ssl_write() will fragment the input if 2392 * necessary and return the number of bytes written; it is up 2393 * to the caller to call \c mbedtls_ssl_write() again in 2394 * order to send the remaining bytes if any. 2395 * 2396 * \param ssl SSL context 2397 * 2398 * \return Current maximum fragment length. 2399 */ 2400 size_t mbedtls_ssl_get_max_frag_len( const mbedtls_ssl_context *ssl ); 2401 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ 2402 2403 #if defined(MBEDTLS_X509_CRT_PARSE_C) 2404 /** 2405 * \brief Return the peer certificate from the current connection 2406 * 2407 * Note: Can be NULL in case no certificate was sent during 2408 * the handshake. Different calls for the same connection can 2409 * return the same or different pointers for the same 2410 * certificate and even a different certificate altogether. 2411 * The peer cert CAN change in a single connection if 2412 * renegotiation is performed. 2413 * 2414 * \param ssl SSL context 2415 * 2416 * \return the current peer certificate 2417 */ 2418 const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert( const mbedtls_ssl_context *ssl ); 2419 #endif /* MBEDTLS_X509_CRT_PARSE_C */ 2420 2421 #if defined(MBEDTLS_SSL_CLI_C) 2422 /** 2423 * \brief Save session in order to resume it later (client-side only) 2424 * Session data is copied to presented session structure. 2425 * 2426 * 2427 * \param ssl SSL context 2428 * \param session session context 2429 * 2430 * \return 0 if successful, 2431 * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed, 2432 * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or 2433 * arguments are otherwise invalid. 2434 * 2435 * \note Only the server certificate is copied, and not the full chain, 2436 * so you should not attempt to validate the certificate again 2437 * by calling \c mbedtls_x509_crt_verify() on it. 2438 * Instead, you should use the results from the verification 2439 * in the original handshake by calling \c mbedtls_ssl_get_verify_result() 2440 * after loading the session again into a new SSL context 2441 * using \c mbedtls_ssl_set_session(). 2442 * 2443 * \note Once the session object is not needed anymore, you should 2444 * free it by calling \c mbedtls_ssl_session_free(). 2445 * 2446 * \sa mbedtls_ssl_set_session() 2447 */ 2448 int mbedtls_ssl_get_session( const mbedtls_ssl_context *ssl, mbedtls_ssl_session *session ); 2449 #endif /* MBEDTLS_SSL_CLI_C */ 2450 2451 /** 2452 * \brief Perform the SSL handshake 2453 * 2454 * \param ssl SSL context 2455 * 2456 * \return 0 if successful, or 2457 * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or 2458 * MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED (see below), or 2459 * a specific SSL error code. 2460 * 2461 * \note If this function returns something other than 0 or 2462 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2463 * becomes unusable, and you should either free it or call 2464 * \c mbedtls_ssl_session_reset() on it before re-using it for 2465 * a new connection; the current connection must be closed. 2466 * 2467 * \note If DTLS is in use, then you may choose to handle 2468 * MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging 2469 * purposes, as it is an expected return value rather than an 2470 * actual error, but you still need to reset/free the context. 2471 */ 2472 int mbedtls_ssl_handshake( mbedtls_ssl_context *ssl ); 2473 2474 /** 2475 * \brief Perform a single step of the SSL handshake 2476 * 2477 * \note The state of the context (ssl->state) will be at 2478 * the next state after execution of this function. Do not 2479 * call this function if state is MBEDTLS_SSL_HANDSHAKE_OVER. 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 * \param ssl SSL context 2488 * 2489 * \return 0 if successful, or 2490 * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or 2491 * a specific SSL error code. 2492 */ 2493 int mbedtls_ssl_handshake_step( mbedtls_ssl_context *ssl ); 2494 2495 #if defined(MBEDTLS_SSL_RENEGOTIATION) 2496 /** 2497 * \brief Initiate an SSL renegotiation on the running connection. 2498 * Client: perform the renegotiation right now. 2499 * Server: request renegotiation, which will be performed 2500 * during the next call to mbedtls_ssl_read() if honored by 2501 * client. 2502 * 2503 * \param ssl SSL context 2504 * 2505 * \return 0 if successful, or any mbedtls_ssl_handshake() return 2506 * value. 2507 * 2508 * \note If this function returns something other than 0 or 2509 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2510 * becomes unusable, and you should either free it or call 2511 * \c mbedtls_ssl_session_reset() on it before re-using it for 2512 * a new connection; the current connection must be closed. 2513 */ 2514 int mbedtls_ssl_renegotiate( mbedtls_ssl_context *ssl ); 2515 #endif /* MBEDTLS_SSL_RENEGOTIATION */ 2516 2517 /** 2518 * \brief Read at most 'len' application data bytes 2519 * 2520 * \param ssl SSL context 2521 * \param buf buffer that will hold the data 2522 * \param len maximum number of bytes to read 2523 * 2524 * \return the number of bytes read, or 2525 * 0 for EOF, or 2526 * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or 2527 * MBEDTLS_ERR_SSL_CLIENT_RECONNECT (see below), or 2528 * another negative error code. 2529 * 2530 * \note If this function returns something other than a positive 2531 * value or MBEDTLS_ERR_SSL_WANT_READ/WRITE or 2532 * MBEDTLS_ERR_SSL_CLIENT_RECONNECT, then the ssl context 2533 * becomes unusable, and you should either free it or call 2534 * \c mbedtls_ssl_session_reset() on it before re-using it for 2535 * a new connection; the current connection must be closed. 2536 * 2537 * \note When this function return MBEDTLS_ERR_SSL_CLIENT_RECONNECT 2538 * (which can only happen server-side), it means that a client 2539 * is initiating a new connection using the same source port. 2540 * You can either treat that as a connection close and wait 2541 * for the client to resend a ClientHello, or directly 2542 * continue with \c mbedtls_ssl_handshake() with the same 2543 * context (as it has beeen reset internally). Either way, you 2544 * should make sure this is seen by the application as a new 2545 * connection: application state, if any, should be reset, and 2546 * most importantly the identity of the client must be checked 2547 * again. WARNING: not validating the identity of the client 2548 * again, or not transmitting the new identity to the 2549 * application layer, would allow authentication bypass! 2550 */ 2551 int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len ); 2552 2553 /** 2554 * \brief Try to write exactly 'len' application data bytes 2555 * 2556 * \warning This function will do partial writes in some cases. If the 2557 * return value is non-negative but less than length, the 2558 * function must be called again with updated arguments: 2559 * buf + ret, len - ret (if ret is the return value) until 2560 * it returns a value equal to the last 'len' argument. 2561 * 2562 * \param ssl SSL context 2563 * \param buf buffer holding the data 2564 * \param len how many bytes must be written 2565 * 2566 * \return the number of bytes actually written (may be less than len), 2567 * or MBEDTLS_ERR_SSL_WANT_WRITE or MBEDTLS_ERR_SSL_WANT_READ, 2568 * or another negative error code. 2569 * 2570 * \note If this function returns something other than 0, a positive 2571 * value or MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop 2572 * using the SSL context for reading or writing, and either 2573 * free it or call \c mbedtls_ssl_session_reset() on it before 2574 * re-using it for a new connection; the current connection 2575 * must be closed. 2576 * 2577 * \note When this function returns MBEDTLS_ERR_SSL_WANT_WRITE/READ, 2578 * it must be called later with the *same* arguments, 2579 * until it returns a value greater that or equal to 0. When 2580 * the function returns MBEDTLS_ERR_SSL_WANT_WRITE there may be 2581 * some partial data in the output buffer, however this is not 2582 * yet sent. 2583 * 2584 * \note If the requested length is greater than the maximum 2585 * fragment length (either the built-in limit or the one set 2586 * or negotiated with the peer), then: 2587 * - with TLS, less bytes than requested are written. 2588 * - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned. 2589 * \c mbedtls_ssl_get_max_frag_len() may be used to query the 2590 * active maximum fragment length. 2591 * 2592 * \note Attempting to write 0 bytes will result in an empty TLS 2593 * application record being sent. 2594 */ 2595 int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len ); 2596 2597 /** 2598 * \brief Send an alert message 2599 * 2600 * \param ssl SSL context 2601 * \param level The alert level of the message 2602 * (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL) 2603 * \param message The alert message (SSL_ALERT_MSG_*) 2604 * 2605 * \return 0 if successful, or a specific SSL error code. 2606 * 2607 * \note If this function returns something other than 0 or 2608 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2609 * becomes unusable, and you should either free it or call 2610 * \c mbedtls_ssl_session_reset() on it before re-using it for 2611 * a new connection; the current connection must be closed. 2612 */ 2613 int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl, 2614 unsigned char level, 2615 unsigned char message ); 2616 /** 2617 * \brief Notify the peer that the connection is being closed 2618 * 2619 * \param ssl SSL context 2620 * 2621 * \return 0 if successful, or a specific SSL error code. 2622 * 2623 * \note If this function returns something other than 0 or 2624 * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context 2625 * becomes unusable, and you should either free it or call 2626 * \c mbedtls_ssl_session_reset() on it before re-using it for 2627 * a new connection; the current connection must be closed. 2628 */ 2629 int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl ); 2630 2631 /** 2632 * \brief Free referenced items in an SSL context and clear memory 2633 * 2634 * \param ssl SSL context 2635 */ 2636 void mbedtls_ssl_free( mbedtls_ssl_context *ssl ); 2637 2638 /** 2639 * \brief Initialize an SSL configuration context 2640 * Just makes the context ready for 2641 * mbedtls_ssl_config_defaults() or mbedtls_ssl_config_free(). 2642 * 2643 * \note You need to call mbedtls_ssl_config_defaults() unless you 2644 * manually set all of the relevant fields yourself. 2645 * 2646 * \param conf SSL configuration context 2647 */ 2648 void mbedtls_ssl_config_init( mbedtls_ssl_config *conf ); 2649 2650 /** 2651 * \brief Load reasonnable default SSL configuration values. 2652 * (You need to call mbedtls_ssl_config_init() first.) 2653 * 2654 * \param conf SSL configuration context 2655 * \param endpoint MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER 2656 * \param transport MBEDTLS_SSL_TRANSPORT_STREAM for TLS, or 2657 * MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS 2658 * \param preset a MBEDTLS_SSL_PRESET_XXX value 2659 * 2660 * \note See \c mbedtls_ssl_conf_transport() for notes on DTLS. 2661 * 2662 * \return 0 if successful, or 2663 * MBEDTLS_ERR_XXX_ALLOC_FAILED on memory allocation error. 2664 */ 2665 int mbedtls_ssl_config_defaults( mbedtls_ssl_config *conf, 2666 int endpoint, int transport, int preset ); 2667 2668 /** 2669 * \brief Free an SSL configuration context 2670 * 2671 * \param conf SSL configuration context 2672 */ 2673 void mbedtls_ssl_config_free( mbedtls_ssl_config *conf ); 2674 2675 /** 2676 * \brief Initialize SSL session structure 2677 * 2678 * \param session SSL session 2679 */ 2680 void mbedtls_ssl_session_init( mbedtls_ssl_session *session ); 2681 2682 /** 2683 * \brief Free referenced items in an SSL session including the 2684 * peer certificate and clear memory 2685 * 2686 * \note A session object can be freed even if the SSL context 2687 * that was used to retrieve the session is still in use. 2688 * 2689 * \param session SSL session 2690 */ 2691 void mbedtls_ssl_session_free( mbedtls_ssl_session *session ); 2692 2693 #ifdef __cplusplus 2694 } 2695 #endif 2696 2697 #endif /* ssl.h */ 2698