|  | /** | 
|  | * \file ssl.h | 
|  | * | 
|  | * \brief SSL/TLS functions. | 
|  | */ | 
|  | /* | 
|  | *  Copyright The Mbed TLS Contributors | 
|  | *  SPDX-License-Identifier: Apache-2.0 | 
|  | * | 
|  | *  Licensed under the Apache License, Version 2.0 (the "License"); you may | 
|  | *  not use this file except in compliance with the License. | 
|  | *  You may obtain a copy of the License at | 
|  | * | 
|  | *  http://www.apache.org/licenses/LICENSE-2.0 | 
|  | * | 
|  | *  Unless required by applicable law or agreed to in writing, software | 
|  | *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT | 
|  | *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
|  | *  See the License for the specific language governing permissions and | 
|  | *  limitations under the License. | 
|  | */ | 
|  | #ifndef MBEDTLS_SSL_H | 
|  | #define MBEDTLS_SSL_H | 
|  | #include "mbedtls/platform_util.h" | 
|  | #include "mbedtls/private_access.h" | 
|  |  | 
|  | #include "mbedtls/build_info.h" | 
|  |  | 
|  | #include "mbedtls/bignum.h" | 
|  | #include "mbedtls/ecp.h" | 
|  |  | 
|  | #include "mbedtls/ssl_ciphersuites.h" | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | #include "mbedtls/x509_crt.h" | 
|  | #include "mbedtls/x509_crl.h" | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_DHM_C) | 
|  | #include "mbedtls/dhm.h" | 
|  | #endif | 
|  |  | 
|  | #include "mbedtls/md.h" | 
|  |  | 
|  | #if defined(MBEDTLS_ECDH_C) | 
|  | #include "mbedtls/ecdh.h" | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_HAVE_TIME) | 
|  | #include "mbedtls/platform_time.h" | 
|  | #endif | 
|  |  | 
|  | #include "psa/crypto.h" | 
|  |  | 
|  | /* | 
|  | * SSL Error codes | 
|  | */ | 
|  | /** A cryptographic operation is in progress. Try again later. */ | 
|  | #define MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS                -0x7000 | 
|  | /** The requested feature is not available. */ | 
|  | #define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE               -0x7080 | 
|  | /** Bad input parameters to function. */ | 
|  | #define MBEDTLS_ERR_SSL_BAD_INPUT_DATA                    -0x7100 | 
|  | /** Verification of the message MAC failed. */ | 
|  | #define MBEDTLS_ERR_SSL_INVALID_MAC                       -0x7180 | 
|  | /** An invalid SSL record was received. */ | 
|  | #define MBEDTLS_ERR_SSL_INVALID_RECORD                    -0x7200 | 
|  | /** The connection indicated an EOF. */ | 
|  | #define MBEDTLS_ERR_SSL_CONN_EOF                          -0x7280 | 
|  | /** A message could not be parsed due to a syntactic error. */ | 
|  | #define MBEDTLS_ERR_SSL_DECODE_ERROR                      -0x7300 | 
|  | /* Error space gap */ | 
|  | /** No RNG was provided to the SSL module. */ | 
|  | #define MBEDTLS_ERR_SSL_NO_RNG                            -0x7400 | 
|  | /** No client certification received from the client, but required by the authentication mode. */ | 
|  | #define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE             -0x7480 | 
|  | /** Client received an extended server hello containing an unsupported extension */ | 
|  | #define MBEDTLS_ERR_SSL_UNSUPPORTED_EXTENSION             -0x7500 | 
|  | /** No ALPN protocols supported that the client advertises */ | 
|  | #define MBEDTLS_ERR_SSL_NO_APPLICATION_PROTOCOL           -0x7580 | 
|  | /** The own private key or pre-shared key is not set, but needed. */ | 
|  | #define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED              -0x7600 | 
|  | /** No CA Chain is set, but required to operate. */ | 
|  | #define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED                 -0x7680 | 
|  | /** An unexpected message was received from our peer. */ | 
|  | #define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE                -0x7700 | 
|  | /** A fatal alert message was received from our peer. */ | 
|  | #define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE               -0x7780 | 
|  | /** No server could be identified matching the client's SNI. */ | 
|  | #define MBEDTLS_ERR_SSL_UNRECOGNIZED_NAME                 -0x7800 | 
|  | /** The peer notified us that the connection is going to be closed. */ | 
|  | #define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY                 -0x7880 | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /** Processing of the Certificate handshake message failed. */ | 
|  | #define MBEDTLS_ERR_SSL_BAD_CERTIFICATE                   -0x7A00 | 
|  | /* Error space gap */ | 
|  | /** | 
|  | * Received NewSessionTicket Post Handshake Message. | 
|  | * This error code is experimental and may be changed or removed without notice. | 
|  | */ | 
|  | #define MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET       -0x7B00 | 
|  | /** Not possible to read early data */ | 
|  | #define MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA            -0x7B80 | 
|  | /** Not possible to write early data */ | 
|  | #define MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA           -0x7C00 | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /** Cache entry not found */ | 
|  | #define MBEDTLS_ERR_SSL_CACHE_ENTRY_NOT_FOUND             -0x7E80 | 
|  | /** Memory allocation failed */ | 
|  | #define MBEDTLS_ERR_SSL_ALLOC_FAILED                      -0x7F00 | 
|  | /** Hardware acceleration function returned with error */ | 
|  | #define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED                   -0x7F80 | 
|  | /** Hardware acceleration function skipped / left alone data */ | 
|  | #define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH              -0x6F80 | 
|  | /** Handshake protocol not within min/max boundaries */ | 
|  | #define MBEDTLS_ERR_SSL_BAD_PROTOCOL_VERSION              -0x6E80 | 
|  | /** The handshake negotiation failed. */ | 
|  | #define MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE                 -0x6E00 | 
|  | /** Session ticket has expired. */ | 
|  | #define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED            -0x6D80 | 
|  | /** Public key type mismatch (eg, asked for RSA key exchange and presented EC key) */ | 
|  | #define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH                  -0x6D00 | 
|  | /** Unknown identity received (eg, PSK identity) */ | 
|  | #define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY                  -0x6C80 | 
|  | /** Internal error (eg, unexpected failure in lower-level module) */ | 
|  | #define MBEDTLS_ERR_SSL_INTERNAL_ERROR                    -0x6C00 | 
|  | /** A counter would wrap (eg, too many messages exchanged). */ | 
|  | #define MBEDTLS_ERR_SSL_COUNTER_WRAPPING                  -0x6B80 | 
|  | /** Unexpected message at ServerHello in renegotiation. */ | 
|  | #define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO       -0x6B00 | 
|  | /** DTLS client must retry for hello verification */ | 
|  | #define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED             -0x6A80 | 
|  | /** A buffer is too small to receive or write a message */ | 
|  | #define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL                  -0x6A00 | 
|  | /* Error space gap */ | 
|  | /** No data of requested type currently available on underlying transport. */ | 
|  | #define MBEDTLS_ERR_SSL_WANT_READ                         -0x6900 | 
|  | /** Connection requires a write call. */ | 
|  | #define MBEDTLS_ERR_SSL_WANT_WRITE                        -0x6880 | 
|  | /** The operation timed out. */ | 
|  | #define MBEDTLS_ERR_SSL_TIMEOUT                           -0x6800 | 
|  | /** The client initiated a reconnect from the same port. */ | 
|  | #define MBEDTLS_ERR_SSL_CLIENT_RECONNECT                  -0x6780 | 
|  | /** Record header looks valid but is not expected. */ | 
|  | #define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD                 -0x6700 | 
|  | /** The alert message received indicates a non-fatal error. */ | 
|  | #define MBEDTLS_ERR_SSL_NON_FATAL                         -0x6680 | 
|  | /** A field in a message was incorrect or inconsistent with other fields. */ | 
|  | #define MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER                 -0x6600 | 
|  | /** Internal-only message signaling that further message-processing should be done */ | 
|  | #define MBEDTLS_ERR_SSL_CONTINUE_PROCESSING               -0x6580 | 
|  | /** The asynchronous operation is not completed yet. */ | 
|  | #define MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS                 -0x6500 | 
|  | /** Internal-only message signaling that a message arrived early. */ | 
|  | #define MBEDTLS_ERR_SSL_EARLY_MESSAGE                     -0x6480 | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /* Error space gap */ | 
|  | /** An encrypted DTLS-frame with an unexpected CID was received. */ | 
|  | #define MBEDTLS_ERR_SSL_UNEXPECTED_CID                    -0x6000 | 
|  | /** An operation failed due to an unexpected version or configuration. */ | 
|  | #define MBEDTLS_ERR_SSL_VERSION_MISMATCH                  -0x5F00 | 
|  | /** Invalid value in SSL config */ | 
|  | #define MBEDTLS_ERR_SSL_BAD_CONFIG                        -0x5E80 | 
|  |  | 
|  | /* | 
|  | * Constants from RFC 8446 for TLS 1.3 PSK modes | 
|  | * | 
|  | * Those are used in the Pre-Shared Key Exchange Modes extension. | 
|  | * See Section 4.2.9 in RFC 8446. | 
|  | */ | 
|  | #define MBEDTLS_SSL_TLS1_3_PSK_MODE_PURE  0 /* Pure PSK-based exchange  */ | 
|  | #define MBEDTLS_SSL_TLS1_3_PSK_MODE_ECDHE 1 /* PSK+ECDHE-based exchange */ | 
|  |  | 
|  | /* | 
|  | * TLS 1.3 NamedGroup values | 
|  | * | 
|  | * From RF 8446 | 
|  | *    enum { | 
|  | *         // Elliptic Curve Groups (ECDHE) | 
|  | *         secp256r1(0x0017), secp384r1(0x0018), secp521r1(0x0019), | 
|  | *         x25519(0x001D), x448(0x001E), | 
|  | *         // Finite Field Groups (DHE) | 
|  | *         ffdhe2048(0x0100), ffdhe3072(0x0101), ffdhe4096(0x0102), | 
|  | *         ffdhe6144(0x0103), ffdhe8192(0x0104), | 
|  | *         // Reserved Code Points | 
|  | *         ffdhe_private_use(0x01FC..0x01FF), | 
|  | *         ecdhe_private_use(0xFE00..0xFEFF), | 
|  | *         (0xFFFF) | 
|  | *     } NamedGroup; | 
|  | * | 
|  | */ | 
|  |  | 
|  | /* Elliptic Curve Groups (ECDHE) */ | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_NONE               0 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP192K1     0x0012 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP192R1     0x0013 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP224K1     0x0014 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP224R1     0x0015 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP256K1     0x0016 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP256R1     0x0017 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP384R1     0x0018 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_SECP521R1     0x0019 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_BP256R1       0x001A | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_BP384R1       0x001B | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_BP512R1       0x001C | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_X25519        0x001D | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_X448          0x001E | 
|  | /* Finite Field Groups (DHE) */ | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE2048     0x0100 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE3072     0x0101 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE4096     0x0102 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE6144     0x0103 | 
|  | #define MBEDTLS_SSL_IANA_TLS_GROUP_FFDHE8192     0x0104 | 
|  |  | 
|  | /* | 
|  | * TLS 1.3 Key Exchange Modes | 
|  | * | 
|  | * Mbed TLS internal identifiers for use with the SSL configuration API | 
|  | * mbedtls_ssl_conf_tls13_key_exchange_modes(). | 
|  | */ | 
|  |  | 
|  | #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK            (1u << 0)   /*!< Pure-PSK TLS 1.3 key exchange, | 
|  | *   encompassing both externally agreed PSKs | 
|  | *   as well as resumption PSKs. */ | 
|  | #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL      (1u << 1)   /*!< Pure-Ephemeral TLS 1.3 key exchanges, | 
|  | *   including for example ECDHE and DHE | 
|  | *   key exchanges. */ | 
|  | #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL  (1u << 2)   /*!< PSK-Ephemeral TLS 1.3 key exchanges, | 
|  | *   using both a PSK and an ephemeral | 
|  | *   key exchange. */ | 
|  |  | 
|  | /* Convenience macros for sets of key exchanges. */ | 
|  | #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_ALL                         \ | 
|  | (MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK              |            \ | 
|  | MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL    |            \ | 
|  | MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL)          /*!< All TLS 1.3 key exchanges           */ | 
|  | #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL                     \ | 
|  | (MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK              |            \ | 
|  | MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL)      /*!< All PSK-based TLS 1.3 key exchanges */ | 
|  | #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL               \ | 
|  | (MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL        |            \ | 
|  | MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL)      /*!< All ephemeral TLS 1.3 key exchanges */ | 
|  |  | 
|  | #define MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_NONE   (0) | 
|  |  | 
|  | /* | 
|  | * Various constants | 
|  | */ | 
|  |  | 
|  | #if !defined(MBEDTLS_DEPRECATED_REMOVED) | 
|  | /* These are the high and low bytes of ProtocolVersion as defined by: | 
|  | * - RFC 5246: ProtocolVersion version = { 3, 3 };     // TLS v1.2 | 
|  | * - RFC 8446: see section 4.2.1 | 
|  | */ | 
|  | #define MBEDTLS_SSL_MAJOR_VERSION_3             3 | 
|  | #define MBEDTLS_SSL_MINOR_VERSION_3             3   /*!< TLS v1.2 */ | 
|  | #define MBEDTLS_SSL_MINOR_VERSION_4             4   /*!< TLS v1.3 */ | 
|  | #endif /* MBEDTLS_DEPRECATED_REMOVED */ | 
|  |  | 
|  | #define MBEDTLS_SSL_TRANSPORT_STREAM            0   /*!< TLS      */ | 
|  | #define MBEDTLS_SSL_TRANSPORT_DATAGRAM          1   /*!< DTLS     */ | 
|  |  | 
|  | #define MBEDTLS_SSL_MAX_HOST_NAME_LEN           255 /*!< Maximum host name defined in RFC 1035 */ | 
|  | #define MBEDTLS_SSL_MAX_ALPN_NAME_LEN           255 /*!< Maximum size in bytes of a protocol name in alpn ext., RFC 7301 */ | 
|  |  | 
|  | #define MBEDTLS_SSL_MAX_ALPN_LIST_LEN           65535 /*!< Maximum size in bytes of list in alpn ext., RFC 7301          */ | 
|  |  | 
|  | /* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c | 
|  | * NONE must be zero so that memset()ing structure to zero works */ | 
|  | #define MBEDTLS_SSL_MAX_FRAG_LEN_NONE           0   /*!< don't use this extension   */ | 
|  | #define MBEDTLS_SSL_MAX_FRAG_LEN_512            1   /*!< MaxFragmentLength 2^9      */ | 
|  | #define MBEDTLS_SSL_MAX_FRAG_LEN_1024           2   /*!< MaxFragmentLength 2^10     */ | 
|  | #define MBEDTLS_SSL_MAX_FRAG_LEN_2048           3   /*!< MaxFragmentLength 2^11     */ | 
|  | #define MBEDTLS_SSL_MAX_FRAG_LEN_4096           4   /*!< MaxFragmentLength 2^12     */ | 
|  | #define MBEDTLS_SSL_MAX_FRAG_LEN_INVALID        5   /*!< first invalid value        */ | 
|  |  | 
|  | #define MBEDTLS_SSL_IS_CLIENT                   0 | 
|  | #define MBEDTLS_SSL_IS_SERVER                   1 | 
|  |  | 
|  | #define MBEDTLS_SSL_EXTENDED_MS_DISABLED        0 | 
|  | #define MBEDTLS_SSL_EXTENDED_MS_ENABLED         1 | 
|  |  | 
|  | #define MBEDTLS_SSL_CID_DISABLED                0 | 
|  | #define MBEDTLS_SSL_CID_ENABLED                 1 | 
|  |  | 
|  | #define MBEDTLS_SSL_ETM_DISABLED                0 | 
|  | #define MBEDTLS_SSL_ETM_ENABLED                 1 | 
|  |  | 
|  | #define MBEDTLS_SSL_COMPRESS_NULL               0 | 
|  |  | 
|  | #define MBEDTLS_SSL_VERIFY_NONE                 0 | 
|  | #define MBEDTLS_SSL_VERIFY_OPTIONAL             1 | 
|  | #define MBEDTLS_SSL_VERIFY_REQUIRED             2 | 
|  | #define MBEDTLS_SSL_VERIFY_UNSET                3 /* Used only for sni_authmode */ | 
|  |  | 
|  | #define MBEDTLS_SSL_LEGACY_RENEGOTIATION        0 | 
|  | #define MBEDTLS_SSL_SECURE_RENEGOTIATION        1 | 
|  |  | 
|  | #define MBEDTLS_SSL_RENEGOTIATION_DISABLED      0 | 
|  | #define MBEDTLS_SSL_RENEGOTIATION_ENABLED       1 | 
|  |  | 
|  | #define MBEDTLS_SSL_ANTI_REPLAY_DISABLED        0 | 
|  | #define MBEDTLS_SSL_ANTI_REPLAY_ENABLED         1 | 
|  |  | 
|  | #define MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED  -1 | 
|  | #define MBEDTLS_SSL_RENEGO_MAX_RECORDS_DEFAULT  16 | 
|  |  | 
|  | #define MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION     0 | 
|  | #define MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION  1 | 
|  | #define MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE      2 | 
|  |  | 
|  | #define MBEDTLS_SSL_TRUNC_HMAC_DISABLED         0 | 
|  | #define MBEDTLS_SSL_TRUNC_HMAC_ENABLED          1 | 
|  | #define MBEDTLS_SSL_TRUNCATED_HMAC_LEN          10  /* 80 bits, rfc 6066 section 7 */ | 
|  |  | 
|  | #define MBEDTLS_SSL_SESSION_TICKETS_DISABLED     0 | 
|  | #define MBEDTLS_SSL_SESSION_TICKETS_ENABLED      1 | 
|  |  | 
|  | #define MBEDTLS_SSL_PRESET_DEFAULT              0 | 
|  | #define MBEDTLS_SSL_PRESET_SUITEB               2 | 
|  |  | 
|  | #define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED       1 | 
|  | #define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED      0 | 
|  |  | 
|  | #define MBEDTLS_SSL_EARLY_DATA_DISABLED        0 | 
|  | #define MBEDTLS_SSL_EARLY_DATA_ENABLED         1 | 
|  |  | 
|  | #define MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED    0 | 
|  | #define MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED      1 | 
|  |  | 
|  | #define MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_CLIENT  1 | 
|  | #define MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER  0 | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS) | 
|  | #if defined(PSA_WANT_ALG_SHA_384) | 
|  | #define MBEDTLS_SSL_TLS1_3_TICKET_RESUMPTION_KEY_LEN        48 | 
|  | #elif defined(PSA_WANT_ALG_SHA_256) | 
|  | #define MBEDTLS_SSL_TLS1_3_TICKET_RESUMPTION_KEY_LEN        32 | 
|  | #endif | 
|  | #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */ | 
|  | /* | 
|  | * Default range for DTLS retransmission timer value, in milliseconds. | 
|  | * RFC 6347 4.2.4.1 says from 1 second to 60 seconds. | 
|  | */ | 
|  | #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MIN    1000 | 
|  | #define MBEDTLS_SSL_DTLS_TIMEOUT_DFL_MAX   60000 | 
|  |  | 
|  | /** | 
|  | * \name SECTION: Module settings | 
|  | * | 
|  | * The configuration options you can set for this module are in this section. | 
|  | * Either change them in mbedtls_config.h or define them on the compiler command line. | 
|  | * \{ | 
|  | */ | 
|  |  | 
|  | /* | 
|  | * Maximum fragment length in bytes, | 
|  | * determines the size of each of the two internal I/O buffers. | 
|  | * | 
|  | * Note: the RFC defines the default size of SSL / TLS messages. If you | 
|  | * change the value here, other clients / servers may not be able to | 
|  | * communicate with you anymore. Only change this value if you control | 
|  | * both sides of the connection and have it reduced at both sides, or | 
|  | * if you're using the Max Fragment Length extension and you know all your | 
|  | * peers are using it too! | 
|  | */ | 
|  | #if !defined(MBEDTLS_SSL_IN_CONTENT_LEN) | 
|  | #define MBEDTLS_SSL_IN_CONTENT_LEN 16384 | 
|  | #endif | 
|  |  | 
|  | #if !defined(MBEDTLS_SSL_OUT_CONTENT_LEN) | 
|  | #define MBEDTLS_SSL_OUT_CONTENT_LEN 16384 | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * Maximum number of heap-allocated bytes for the purpose of | 
|  | * DTLS handshake message reassembly and future message buffering. | 
|  | */ | 
|  | #if !defined(MBEDTLS_SSL_DTLS_MAX_BUFFERING) | 
|  | #define MBEDTLS_SSL_DTLS_MAX_BUFFERING 32768 | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * Maximum length of CIDs for incoming and outgoing messages. | 
|  | */ | 
|  | #if !defined(MBEDTLS_SSL_CID_IN_LEN_MAX) | 
|  | #define MBEDTLS_SSL_CID_IN_LEN_MAX          32 | 
|  | #endif | 
|  |  | 
|  | #if !defined(MBEDTLS_SSL_CID_OUT_LEN_MAX) | 
|  | #define MBEDTLS_SSL_CID_OUT_LEN_MAX         32 | 
|  | #endif | 
|  |  | 
|  | #if !defined(MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY) | 
|  | #define MBEDTLS_SSL_CID_TLS1_3_PADDING_GRANULARITY 16 | 
|  | #endif | 
|  |  | 
|  | /** \} name SECTION: Module settings */ | 
|  |  | 
|  | /* | 
|  | * Default to standard CID mode | 
|  | */ | 
|  | #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) && \ | 
|  | !defined(MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT) | 
|  | #define MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT 0 | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * Length of the verify data for secure renegotiation | 
|  | */ | 
|  | #define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 12 | 
|  |  | 
|  | /* | 
|  | * Signaling ciphersuite values (SCSV) | 
|  | */ | 
|  | #define MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO    0xFF   /**< renegotiation info ext */ | 
|  |  | 
|  | /* | 
|  | * Supported Signature and Hash algorithms (For TLS 1.2) | 
|  | * RFC 5246 section 7.4.1.4.1 | 
|  | */ | 
|  | #define MBEDTLS_SSL_HASH_NONE                0 | 
|  | #define MBEDTLS_SSL_HASH_MD5                 1 | 
|  | #define MBEDTLS_SSL_HASH_SHA1                2 | 
|  | #define MBEDTLS_SSL_HASH_SHA224              3 | 
|  | #define MBEDTLS_SSL_HASH_SHA256              4 | 
|  | #define MBEDTLS_SSL_HASH_SHA384              5 | 
|  | #define MBEDTLS_SSL_HASH_SHA512              6 | 
|  |  | 
|  | #define MBEDTLS_SSL_SIG_ANON                 0 | 
|  | #define MBEDTLS_SSL_SIG_RSA                  1 | 
|  | #define MBEDTLS_SSL_SIG_ECDSA                3 | 
|  |  | 
|  | /* | 
|  | * TLS 1.3 signature algorithms | 
|  | * RFC 8446, Section 4.2.2 | 
|  | */ | 
|  |  | 
|  | /* RSASSA-PKCS1-v1_5 algorithms */ | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA256 0x0401 | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA384 0x0501 | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA512 0x0601 | 
|  |  | 
|  | /* ECDSA algorithms */ | 
|  | #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP256R1_SHA256 0x0403 | 
|  | #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP384R1_SHA384 0x0503 | 
|  | #define MBEDTLS_TLS1_3_SIG_ECDSA_SECP521R1_SHA512 0x0603 | 
|  |  | 
|  | /* RSASSA-PSS algorithms with public key OID rsaEncryption */ | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA256 0x0804 | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA384 0x0805 | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA512 0x0806 | 
|  |  | 
|  | /* EdDSA algorithms */ | 
|  | #define MBEDTLS_TLS1_3_SIG_ED25519 0x0807 | 
|  | #define MBEDTLS_TLS1_3_SIG_ED448 0x0808 | 
|  |  | 
|  | /* RSASSA-PSS algorithms with public key OID RSASSA-PSS  */ | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA256 0x0809 | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA384 0x080A | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PSS_PSS_SHA512 0x080B | 
|  |  | 
|  | /* LEGACY ALGORITHMS */ | 
|  | #define MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA1 0x0201 | 
|  | #define MBEDTLS_TLS1_3_SIG_ECDSA_SHA1     0x0203 | 
|  |  | 
|  | #define MBEDTLS_TLS1_3_SIG_NONE 0x0 | 
|  |  | 
|  | /* | 
|  | * Client Certificate Types | 
|  | * RFC 5246 section 7.4.4 plus RFC 4492 section 5.5 | 
|  | */ | 
|  | #define MBEDTLS_SSL_CERT_TYPE_RSA_SIGN       1 | 
|  | #define MBEDTLS_SSL_CERT_TYPE_ECDSA_SIGN    64 | 
|  |  | 
|  | /* | 
|  | * Message, alert and handshake types | 
|  | */ | 
|  | #define MBEDTLS_SSL_MSG_CHANGE_CIPHER_SPEC     20 | 
|  | #define MBEDTLS_SSL_MSG_ALERT                  21 | 
|  | #define MBEDTLS_SSL_MSG_HANDSHAKE              22 | 
|  | #define MBEDTLS_SSL_MSG_APPLICATION_DATA       23 | 
|  | #define MBEDTLS_SSL_MSG_CID                    25 | 
|  |  | 
|  | #define MBEDTLS_SSL_ALERT_LEVEL_WARNING         1 | 
|  | #define MBEDTLS_SSL_ALERT_LEVEL_FATAL           2 | 
|  |  | 
|  | #define MBEDTLS_SSL_ALERT_MSG_CLOSE_NOTIFY           0  /* 0x00 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE    10  /* 0x0A */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_BAD_RECORD_MAC        20  /* 0x14 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_DECRYPTION_FAILED     21  /* 0x15 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_RECORD_OVERFLOW       22  /* 0x16 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_DECOMPRESSION_FAILURE 30  /* 0x1E */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE     40  /* 0x28 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_NO_CERT               41  /* 0x29 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_BAD_CERT              42  /* 0x2A */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_CERT      43  /* 0x2B */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_CERT_REVOKED          44  /* 0x2C */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_CERT_EXPIRED          45  /* 0x2D */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_CERT_UNKNOWN          46  /* 0x2E */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER     47  /* 0x2F */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_CA            48  /* 0x30 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_ACCESS_DENIED         49  /* 0x31 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR          50  /* 0x32 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR         51  /* 0x33 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_EXPORT_RESTRICTION    60  /* 0x3C */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION      70  /* 0x46 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_INSUFFICIENT_SECURITY 71  /* 0x47 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR        80  /* 0x50 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_INAPROPRIATE_FALLBACK 86  /* 0x56 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_USER_CANCELED         90  /* 0x5A */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_NO_RENEGOTIATION     100  /* 0x64 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_MISSING_EXTENSION    109  /* 0x6d -- new in TLS 1.3 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT      110  /* 0x6E */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_UNRECOGNIZED_NAME    112  /* 0x70 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY 115  /* 0x73 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_CERT_REQUIRED        116  /* 0x74 */ | 
|  | #define MBEDTLS_SSL_ALERT_MSG_NO_APPLICATION_PROTOCOL 120 /* 0x78 */ | 
|  |  | 
|  | #define MBEDTLS_SSL_HS_HELLO_REQUEST            0 | 
|  | #define MBEDTLS_SSL_HS_CLIENT_HELLO             1 | 
|  | #define MBEDTLS_SSL_HS_SERVER_HELLO             2 | 
|  | #define MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST     3 | 
|  | #define MBEDTLS_SSL_HS_NEW_SESSION_TICKET       4 | 
|  | #define MBEDTLS_SSL_HS_END_OF_EARLY_DATA        5 | 
|  | #define MBEDTLS_SSL_HS_ENCRYPTED_EXTENSIONS     8 | 
|  | #define MBEDTLS_SSL_HS_CERTIFICATE             11 | 
|  | #define MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE     12 | 
|  | #define MBEDTLS_SSL_HS_CERTIFICATE_REQUEST     13 | 
|  | #define MBEDTLS_SSL_HS_SERVER_HELLO_DONE       14 | 
|  | #define MBEDTLS_SSL_HS_CERTIFICATE_VERIFY      15 | 
|  | #define MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE     16 | 
|  | #define MBEDTLS_SSL_HS_FINISHED                20 | 
|  | #define MBEDTLS_SSL_HS_MESSAGE_HASH           254 | 
|  |  | 
|  | /* | 
|  | * TLS extensions | 
|  | */ | 
|  | #define MBEDTLS_TLS_EXT_SERVERNAME                   0 | 
|  | #define MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME          0 | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH          1 | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_TRUNCATED_HMAC               4 | 
|  | #define MBEDTLS_TLS_EXT_STATUS_REQUEST               5 /* RFC 6066 TLS 1.2 and 1.3 */ | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES   10 | 
|  | #define MBEDTLS_TLS_EXT_SUPPORTED_GROUPS            10 /* RFC 8422,7919 TLS 1.2 and 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS     11 | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_SIG_ALG                     13 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_USE_SRTP                    14 | 
|  | #define MBEDTLS_TLS_EXT_HEARTBEAT                   15 /* RFC 6520 TLS 1.2 and 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_ALPN                        16 | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_SCT                         18 /* RFC 6962 TLS 1.2 and 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_CLI_CERT_TYPE               19 /* RFC 7250 TLS 1.2 and 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_SERV_CERT_TYPE              20 /* RFC 7250 TLS 1.2 and 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_PADDING                     21 /* RFC 7685 TLS 1.2 and 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC            22 /* 0x16 */ | 
|  | #define MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET  0x0017 /* 23 */ | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_RECORD_SIZE_LIMIT           28 /* RFC 8449 (implemented for TLS 1.3 only) */ | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_SESSION_TICKET              35 | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_PRE_SHARED_KEY              41 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_EARLY_DATA                  42 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_SUPPORTED_VERSIONS          43 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_COOKIE                      44 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_PSK_KEY_EXCHANGE_MODES      45 /* RFC 8446 TLS 1.3 */ | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_CERT_AUTH                   47 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_OID_FILTERS                 48 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_POST_HANDSHAKE_AUTH         49 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_SIG_ALG_CERT                50 /* RFC 8446 TLS 1.3 */ | 
|  | #define MBEDTLS_TLS_EXT_KEY_SHARE                   51 /* RFC 8446 TLS 1.3 */ | 
|  |  | 
|  | #if MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT == 0 | 
|  | #define MBEDTLS_TLS_EXT_CID                         54 /* RFC 9146 DTLS 1.2 CID */ | 
|  | #else | 
|  | #define MBEDTLS_TLS_EXT_CID                        254 /* Pre-RFC 9146 DTLS 1.2 CID */ | 
|  | #endif | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP               256 /* experimental */ | 
|  |  | 
|  | #define MBEDTLS_TLS_EXT_RENEGOTIATION_INFO      0xFF01 | 
|  |  | 
|  | /* | 
|  | * Size defines | 
|  | */ | 
|  | #if !defined(MBEDTLS_PSK_MAX_LEN) | 
|  | /* | 
|  | * If the library supports TLS 1.3 tickets and the cipher suite | 
|  | * TLS1-3-AES-256-GCM-SHA384, set the PSK maximum length to 48 instead of 32. | 
|  | * That way, the TLS 1.3 client and server are able to resume sessions where | 
|  | * the cipher suite is TLS1-3-AES-256-GCM-SHA384 (pre-shared keys are 48 | 
|  | * bytes long in that case). | 
|  | */ | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && \ | 
|  | defined(MBEDTLS_SSL_SESSION_TICKETS) && \ | 
|  | defined(MBEDTLS_AES_C) && defined(MBEDTLS_GCM_C) && \ | 
|  | defined(MBEDTLS_MD_CAN_SHA384) | 
|  | #define MBEDTLS_PSK_MAX_LEN 48 /* 384 bits */ | 
|  | #else | 
|  | #define MBEDTLS_PSK_MAX_LEN 32 /* 256 bits */ | 
|  | #endif | 
|  | #endif /* !MBEDTLS_PSK_MAX_LEN */ | 
|  |  | 
|  | /* Dummy type used only for its size */ | 
|  | union mbedtls_ssl_premaster_secret { | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) | 
|  | unsigned char _pms_rsa[48];                         /* RFC 5246 8.1.1 */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) | 
|  | unsigned char _pms_dhm[MBEDTLS_MPI_MAX_SIZE];      /* RFC 5246 8.1.2 */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED)    || \ | 
|  | defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)  || \ | 
|  | defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED)     || \ | 
|  | defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) | 
|  | unsigned char _pms_ecdh[MBEDTLS_ECP_MAX_BYTES];    /* RFC 4492 5.10 */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) | 
|  | unsigned char _pms_psk[4 + 2 * MBEDTLS_PSK_MAX_LEN];       /* RFC 4279 2 */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) | 
|  | unsigned char _pms_dhe_psk[4 + MBEDTLS_MPI_MAX_SIZE | 
|  | + MBEDTLS_PSK_MAX_LEN];         /* RFC 4279 3 */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) | 
|  | unsigned char _pms_rsa_psk[52 + MBEDTLS_PSK_MAX_LEN];      /* RFC 4279 4 */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) | 
|  | unsigned char _pms_ecdhe_psk[4 + MBEDTLS_ECP_MAX_BYTES | 
|  | + MBEDTLS_PSK_MAX_LEN];       /* RFC 5489 2 */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) | 
|  | unsigned char _pms_ecjpake[32];     /* Thread spec: SHA-256 output */ | 
|  | #endif | 
|  | }; | 
|  |  | 
|  | #define MBEDTLS_PREMASTER_SIZE     sizeof(union mbedtls_ssl_premaster_secret) | 
|  |  | 
|  | #define MBEDTLS_TLS1_3_MD_MAX_SIZE         PSA_HASH_MAX_SIZE | 
|  |  | 
|  |  | 
|  | /* Length in number of bytes of the TLS sequence number */ | 
|  | #define MBEDTLS_SSL_SEQUENCE_NUMBER_LEN 8 | 
|  |  | 
|  | #ifdef __cplusplus | 
|  | extern "C" { | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * SSL state machine | 
|  | */ | 
|  | typedef enum { | 
|  | MBEDTLS_SSL_HELLO_REQUEST, | 
|  | MBEDTLS_SSL_CLIENT_HELLO, | 
|  | MBEDTLS_SSL_SERVER_HELLO, | 
|  | MBEDTLS_SSL_SERVER_CERTIFICATE, | 
|  | MBEDTLS_SSL_SERVER_KEY_EXCHANGE, | 
|  | MBEDTLS_SSL_CERTIFICATE_REQUEST, | 
|  | MBEDTLS_SSL_SERVER_HELLO_DONE, | 
|  | MBEDTLS_SSL_CLIENT_CERTIFICATE, | 
|  | MBEDTLS_SSL_CLIENT_KEY_EXCHANGE, | 
|  | MBEDTLS_SSL_CERTIFICATE_VERIFY, | 
|  | MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC, | 
|  | MBEDTLS_SSL_CLIENT_FINISHED, | 
|  | MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC, | 
|  | MBEDTLS_SSL_SERVER_FINISHED, | 
|  | MBEDTLS_SSL_FLUSH_BUFFERS, | 
|  | MBEDTLS_SSL_HANDSHAKE_WRAPUP, | 
|  |  | 
|  | MBEDTLS_SSL_NEW_SESSION_TICKET, | 
|  | MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT, | 
|  | MBEDTLS_SSL_HELLO_RETRY_REQUEST, | 
|  | MBEDTLS_SSL_ENCRYPTED_EXTENSIONS, | 
|  | MBEDTLS_SSL_END_OF_EARLY_DATA, | 
|  | MBEDTLS_SSL_CLIENT_CERTIFICATE_VERIFY, | 
|  | MBEDTLS_SSL_CLIENT_CCS_AFTER_SERVER_FINISHED, | 
|  | MBEDTLS_SSL_CLIENT_CCS_BEFORE_2ND_CLIENT_HELLO, | 
|  | MBEDTLS_SSL_SERVER_CCS_AFTER_SERVER_HELLO, | 
|  | MBEDTLS_SSL_CLIENT_CCS_AFTER_CLIENT_HELLO, | 
|  | MBEDTLS_SSL_SERVER_CCS_AFTER_HELLO_RETRY_REQUEST, | 
|  | MBEDTLS_SSL_HANDSHAKE_OVER, | 
|  | MBEDTLS_SSL_TLS1_3_NEW_SESSION_TICKET, | 
|  | MBEDTLS_SSL_TLS1_3_NEW_SESSION_TICKET_FLUSH, | 
|  | } | 
|  | mbedtls_ssl_states; | 
|  |  | 
|  | /** | 
|  | * \brief          Callback type: send data on the network. | 
|  | * | 
|  | * \note           That callback may be either blocking or non-blocking. | 
|  | * | 
|  | * \param ctx      Context for the send callback (typically a file descriptor) | 
|  | * \param buf      Buffer holding the data to send | 
|  | * \param len      Length of the data to send | 
|  | * | 
|  | * \return         The callback must return the number of bytes sent if any, | 
|  | *                 or a non-zero error code. | 
|  | *                 If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_WRITE | 
|  | *                 must be returned when the operation would block. | 
|  | * | 
|  | * \note           The callback is allowed to send fewer bytes than requested. | 
|  | *                 It must always return the number of bytes actually sent. | 
|  | */ | 
|  | typedef int mbedtls_ssl_send_t(void *ctx, | 
|  | const unsigned char *buf, | 
|  | size_t len); | 
|  |  | 
|  | /** | 
|  | * \brief          Callback type: receive data from the network. | 
|  | * | 
|  | * \note           That callback may be either blocking or non-blocking. | 
|  | * | 
|  | * \param ctx      Context for the receive callback (typically a file | 
|  | *                 descriptor) | 
|  | * \param buf      Buffer to write the received data to | 
|  | * \param len      Length of the receive buffer | 
|  | * | 
|  | * \returns        If data has been received, the positive number of bytes received. | 
|  | * \returns        \c 0 if the connection has been closed. | 
|  | * \returns        If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ | 
|  | *                 must be returned when the operation would block. | 
|  | * \returns        Another negative error code on other kinds of failures. | 
|  | * | 
|  | * \note           The callback may receive fewer bytes than the length of the | 
|  | *                 buffer. It must always return the number of bytes actually | 
|  | *                 received and written to the buffer. | 
|  | */ | 
|  | typedef int mbedtls_ssl_recv_t(void *ctx, | 
|  | unsigned char *buf, | 
|  | size_t len); | 
|  |  | 
|  | /** | 
|  | * \brief          Callback type: receive data from the network, with timeout | 
|  | * | 
|  | * \note           That callback must block until data is received, or the | 
|  | *                 timeout delay expires, or the operation is interrupted by a | 
|  | *                 signal. | 
|  | * | 
|  | * \param ctx      Context for the receive callback (typically a file descriptor) | 
|  | * \param buf      Buffer to write the received data to | 
|  | * \param len      Length of the receive buffer | 
|  | * \param timeout  Maximum number of milliseconds to wait for data | 
|  | *                 0 means no timeout (potentially waiting forever) | 
|  | * | 
|  | * \return         The callback must return the number of bytes received, | 
|  | *                 or a non-zero error code: | 
|  | *                 \c MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out, | 
|  | *                 \c MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal. | 
|  | * | 
|  | * \note           The callback may receive fewer bytes than the length of the | 
|  | *                 buffer. It must always return the number of bytes actually | 
|  | *                 received and written to the buffer. | 
|  | */ | 
|  | typedef int mbedtls_ssl_recv_timeout_t(void *ctx, | 
|  | unsigned char *buf, | 
|  | size_t len, | 
|  | uint32_t timeout); | 
|  | /** | 
|  | * \brief          Callback type: set a pair of timers/delays to watch | 
|  | * | 
|  | * \param ctx      Context pointer | 
|  | * \param int_ms   Intermediate delay in milliseconds | 
|  | * \param fin_ms   Final delay in milliseconds | 
|  | *                 0 cancels the current timer. | 
|  | * | 
|  | * \note           This callback must at least store the necessary information | 
|  | *                 for the associated \c mbedtls_ssl_get_timer_t callback to | 
|  | *                 return correct information. | 
|  | * | 
|  | * \note           If using an event-driven style of programming, an event must | 
|  | *                 be generated when the final delay is passed. The event must | 
|  | *                 cause a call to \c mbedtls_ssl_handshake() with the proper | 
|  | *                 SSL context to be scheduled. Care must be taken to ensure | 
|  | *                 that at most one such call happens at a time. | 
|  | * | 
|  | * \note           Only one timer at a time must be running. Calling this | 
|  | *                 function while a timer is running must cancel it. Cancelled | 
|  | *                 timers must not generate any event. | 
|  | */ | 
|  | typedef void mbedtls_ssl_set_timer_t(void *ctx, | 
|  | uint32_t int_ms, | 
|  | uint32_t fin_ms); | 
|  |  | 
|  | /** | 
|  | * \brief          Callback type: get status of timers/delays | 
|  | * | 
|  | * \param ctx      Context pointer | 
|  | * | 
|  | * \return         This callback must return: | 
|  | *                 -1 if cancelled (fin_ms == 0), | 
|  | *                  0 if none of the delays have passed, | 
|  | *                  1 if only the intermediate delay has passed, | 
|  | *                  2 if the final delay has passed. | 
|  | */ | 
|  | typedef int mbedtls_ssl_get_timer_t(void *ctx); | 
|  |  | 
|  | /* Defined below */ | 
|  | typedef struct mbedtls_ssl_session mbedtls_ssl_session; | 
|  | typedef struct mbedtls_ssl_context mbedtls_ssl_context; | 
|  | typedef struct mbedtls_ssl_config  mbedtls_ssl_config; | 
|  |  | 
|  | /* Defined in library/ssl_misc.h */ | 
|  | typedef struct mbedtls_ssl_transform mbedtls_ssl_transform; | 
|  | typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params; | 
|  | typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t; | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert; | 
|  | #endif | 
|  | #if defined(MBEDTLS_SSL_PROTO_DTLS) | 
|  | typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item; | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS) | 
|  | #define MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_RESUMPTION                          \ | 
|  | MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK                        /* 1U << 0 */ | 
|  | #define MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_EPHEMERAL_RESUMPTION                \ | 
|  | MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL              /* 1U << 2 */ | 
|  | #define MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_EARLY_DATA                  (1U << 3) | 
|  |  | 
|  | #define MBEDTLS_SSL_TLS1_3_TICKET_FLAGS_MASK                                    \ | 
|  | (MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_RESUMPTION             |      \ | 
|  | MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_EPHEMERAL_RESUMPTION   |      \ | 
|  | MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_EARLY_DATA) | 
|  | #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */ | 
|  |  | 
|  | /** | 
|  | * \brief          Callback type: server-side session cache getter | 
|  | * | 
|  | *                 The session cache is logically a key value store, with | 
|  | *                 keys being session IDs and values being instances of | 
|  | *                 mbedtls_ssl_session. | 
|  | * | 
|  | *                 This callback retrieves an entry in this key-value store. | 
|  | * | 
|  | * \param data            The address of the session cache structure to query. | 
|  | * \param session_id      The buffer holding the session ID to query. | 
|  | * \param session_id_len  The length of \p session_id in Bytes. | 
|  | * \param session         The address of the session structure to populate. | 
|  | *                        It is initialized with mbdtls_ssl_session_init(), | 
|  | *                        and the callback must always leave it in a state | 
|  | *                        where it can safely be freed via | 
|  | *                        mbedtls_ssl_session_free() independent of the | 
|  | *                        return code of this function. | 
|  | * | 
|  | * \return                \c 0 on success | 
|  | * \return                A non-zero return value on failure. | 
|  | * | 
|  | */ | 
|  | typedef int mbedtls_ssl_cache_get_t(void *data, | 
|  | unsigned char const *session_id, | 
|  | size_t session_id_len, | 
|  | mbedtls_ssl_session *session); | 
|  | /** | 
|  | * \brief          Callback type: server-side session cache setter | 
|  | * | 
|  | *                 The session cache is logically a key value store, with | 
|  | *                 keys being session IDs and values being instances of | 
|  | *                 mbedtls_ssl_session. | 
|  | * | 
|  | *                 This callback sets an entry in this key-value store. | 
|  | * | 
|  | * \param data            The address of the session cache structure to modify. | 
|  | * \param session_id      The buffer holding the session ID to query. | 
|  | * \param session_id_len  The length of \p session_id in Bytes. | 
|  | * \param session         The address of the session to be stored in the | 
|  | *                        session cache. | 
|  | * | 
|  | * \return                \c 0 on success | 
|  | * \return                A non-zero return value on failure. | 
|  | */ | 
|  | typedef int mbedtls_ssl_cache_set_t(void *data, | 
|  | unsigned char const *session_id, | 
|  | size_t session_id_len, | 
|  | const mbedtls_ssl_session *session); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | /** | 
|  | * \brief           Callback type: start external signature operation. | 
|  | * | 
|  | *                  This callback is called during an SSL handshake to start | 
|  | *                  a signature decryption operation using an | 
|  | *                  external processor. The parameter \p cert contains | 
|  | *                  the public key; it is up to the callback function to | 
|  | *                  determine how to access the associated private key. | 
|  | * | 
|  | *                  This function typically sends or enqueues a request, and | 
|  | *                  does not wait for the operation to complete. This allows | 
|  | *                  the handshake step to be non-blocking. | 
|  | * | 
|  | *                  The parameters \p ssl and \p cert are guaranteed to remain | 
|  | *                  valid throughout the handshake. On the other hand, this | 
|  | *                  function must save the contents of \p hash if the value | 
|  | *                  is needed for later processing, because the \p hash buffer | 
|  | *                  is no longer valid after this function returns. | 
|  | * | 
|  | *                  This function may call mbedtls_ssl_set_async_operation_data() | 
|  | *                  to store an operation context for later retrieval | 
|  | *                  by the resume or cancel callback. | 
|  | * | 
|  | * \note            For RSA signatures, this function must produce output | 
|  | *                  that is consistent with PKCS#1 v1.5 in the same way as | 
|  | *                  mbedtls_rsa_pkcs1_sign(). Before the private key operation, | 
|  | *                  apply the padding steps described in RFC 8017, section 9.2 | 
|  | *                  "EMSA-PKCS1-v1_5" as follows. | 
|  | *                  - If \p md_alg is #MBEDTLS_MD_NONE, apply the PKCS#1 v1.5 | 
|  | *                    encoding, treating \p hash as the DigestInfo to be | 
|  | *                    padded. In other words, apply EMSA-PKCS1-v1_5 starting | 
|  | *                    from step 3, with `T = hash` and `tLen = hash_len`. | 
|  | *                  - If `md_alg != MBEDTLS_MD_NONE`, apply the PKCS#1 v1.5 | 
|  | *                    encoding, treating \p hash as the hash to be encoded and | 
|  | *                    padded. In other words, apply EMSA-PKCS1-v1_5 starting | 
|  | *                    from step 2, with `digestAlgorithm` obtained by calling | 
|  | *                    mbedtls_oid_get_oid_by_md() on \p md_alg. | 
|  | * | 
|  | * \note            For ECDSA signatures, the output format is the DER encoding | 
|  | *                  `Ecdsa-Sig-Value` defined in | 
|  | *                  [RFC 4492 section 5.4](https://tools.ietf.org/html/rfc4492#section-5.4). | 
|  | * | 
|  | * \param ssl             The SSL connection instance. It should not be | 
|  | *                        modified other than via | 
|  | *                        mbedtls_ssl_set_async_operation_data(). | 
|  | * \param cert            Certificate containing the public key. | 
|  | *                        In simple cases, this is one of the pointers passed to | 
|  | *                        mbedtls_ssl_conf_own_cert() when configuring the SSL | 
|  | *                        connection. However, if other callbacks are used, this | 
|  | *                        property may not hold. For example, if an SNI callback | 
|  | *                        is registered with mbedtls_ssl_conf_sni(), then | 
|  | *                        this callback determines what certificate is used. | 
|  | * \param md_alg          Hash algorithm. | 
|  | * \param hash            Buffer containing the hash. This buffer is | 
|  | *                        no longer valid when the function returns. | 
|  | * \param hash_len        Size of the \c hash buffer in bytes. | 
|  | * | 
|  | * \return          0 if the operation was started successfully and the SSL | 
|  | *                  stack should call the resume callback immediately. | 
|  | * \return          #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation | 
|  | *                  was started successfully and the SSL stack should return | 
|  | *                  immediately without calling the resume callback yet. | 
|  | * \return          #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external | 
|  | *                  processor does not support this key. The SSL stack will | 
|  | *                  use the private key object instead. | 
|  | * \return          Any other error indicates a fatal failure and is | 
|  | *                  propagated up the call chain. The callback should | 
|  | *                  use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b> | 
|  | *                  use \c MBEDTLS_ERR_SSL_xxx error codes except as | 
|  | *                  directed in the documentation of this callback. | 
|  | */ | 
|  | typedef int mbedtls_ssl_async_sign_t(mbedtls_ssl_context *ssl, | 
|  | mbedtls_x509_crt *cert, | 
|  | mbedtls_md_type_t md_alg, | 
|  | const unsigned char *hash, | 
|  | size_t hash_len); | 
|  |  | 
|  | /** | 
|  | * \brief           Callback type: start external decryption operation. | 
|  | * | 
|  | *                  This callback is called during an SSL handshake to start | 
|  | *                  an RSA decryption operation using an | 
|  | *                  external processor. The parameter \p cert contains | 
|  | *                  the public key; it is up to the callback function to | 
|  | *                  determine how to access the associated private key. | 
|  | * | 
|  | *                  This function typically sends or enqueues a request, and | 
|  | *                  does not wait for the operation to complete. This allows | 
|  | *                  the handshake step to be non-blocking. | 
|  | * | 
|  | *                  The parameters \p ssl and \p cert are guaranteed to remain | 
|  | *                  valid throughout the handshake. On the other hand, this | 
|  | *                  function must save the contents of \p input if the value | 
|  | *                  is needed for later processing, because the \p input buffer | 
|  | *                  is no longer valid after this function returns. | 
|  | * | 
|  | *                  This function may call mbedtls_ssl_set_async_operation_data() | 
|  | *                  to store an operation context for later retrieval | 
|  | *                  by the resume or cancel callback. | 
|  | * | 
|  | * \warning         RSA decryption as used in TLS is subject to a potential | 
|  | *                  timing side channel attack first discovered by Bleichenbacher | 
|  | *                  in 1998. This attack can be remotely exploitable | 
|  | *                  in practice. To avoid this attack, you must ensure that | 
|  | *                  if the callback performs an RSA decryption, the time it | 
|  | *                  takes to execute and return the result does not depend | 
|  | *                  on whether the RSA decryption succeeded or reported | 
|  | *                  invalid padding. | 
|  | * | 
|  | * \param ssl             The SSL connection instance. It should not be | 
|  | *                        modified other than via | 
|  | *                        mbedtls_ssl_set_async_operation_data(). | 
|  | * \param cert            Certificate containing the public key. | 
|  | *                        In simple cases, this is one of the pointers passed to | 
|  | *                        mbedtls_ssl_conf_own_cert() when configuring the SSL | 
|  | *                        connection. However, if other callbacks are used, this | 
|  | *                        property may not hold. For example, if an SNI callback | 
|  | *                        is registered with mbedtls_ssl_conf_sni(), then | 
|  | *                        this callback determines what certificate is used. | 
|  | * \param input           Buffer containing the input ciphertext. This buffer | 
|  | *                        is no longer valid when the function returns. | 
|  | * \param input_len       Size of the \p input buffer in bytes. | 
|  | * | 
|  | * \return          0 if the operation was started successfully and the SSL | 
|  | *                  stack should call the resume callback immediately. | 
|  | * \return          #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation | 
|  | *                  was started successfully and the SSL stack should return | 
|  | *                  immediately without calling the resume callback yet. | 
|  | * \return          #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external | 
|  | *                  processor does not support this key. The SSL stack will | 
|  | *                  use the private key object instead. | 
|  | * \return          Any other error indicates a fatal failure and is | 
|  | *                  propagated up the call chain. The callback should | 
|  | *                  use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b> | 
|  | *                  use \c MBEDTLS_ERR_SSL_xxx error codes except as | 
|  | *                  directed in the documentation of this callback. | 
|  | */ | 
|  | typedef int mbedtls_ssl_async_decrypt_t(mbedtls_ssl_context *ssl, | 
|  | mbedtls_x509_crt *cert, | 
|  | const unsigned char *input, | 
|  | size_t input_len); | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  |  | 
|  | /** | 
|  | * \brief           Callback type: resume external operation. | 
|  | * | 
|  | *                  This callback is called during an SSL handshake to resume | 
|  | *                  an external operation started by the | 
|  | *                  ::mbedtls_ssl_async_sign_t or | 
|  | *                  ::mbedtls_ssl_async_decrypt_t callback. | 
|  | * | 
|  | *                  This function typically checks the status of a pending | 
|  | *                  request or causes the request queue to make progress, and | 
|  | *                  does not wait for the operation to complete. This allows | 
|  | *                  the handshake step to be non-blocking. | 
|  | * | 
|  | *                  This function may call mbedtls_ssl_get_async_operation_data() | 
|  | *                  to retrieve an operation context set by the start callback. | 
|  | *                  It may call mbedtls_ssl_set_async_operation_data() to modify | 
|  | *                  this context. | 
|  | * | 
|  | *                  Note that when this function returns a status other than | 
|  | *                  #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, it must free any | 
|  | *                  resources associated with the operation. | 
|  | * | 
|  | * \param ssl             The SSL connection instance. It should not be | 
|  | *                        modified other than via | 
|  | *                        mbedtls_ssl_set_async_operation_data(). | 
|  | * \param output          Buffer containing the output (signature or decrypted | 
|  | *                        data) on success. | 
|  | * \param output_len      On success, number of bytes written to \p output. | 
|  | * \param output_size     Size of the \p output buffer in bytes. | 
|  | * | 
|  | * \return          0 if output of the operation is available in the | 
|  | *                  \p output buffer. | 
|  | * \return          #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation | 
|  | *                  is still in progress. Subsequent requests for progress | 
|  | *                  on the SSL connection will call the resume callback | 
|  | *                  again. | 
|  | * \return          Any other error means that the operation is aborted. | 
|  | *                  The SSL handshake is aborted. The callback should | 
|  | *                  use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b> | 
|  | *                  use \c MBEDTLS_ERR_SSL_xxx error codes except as | 
|  | *                  directed in the documentation of this callback. | 
|  | */ | 
|  | typedef int mbedtls_ssl_async_resume_t(mbedtls_ssl_context *ssl, | 
|  | unsigned char *output, | 
|  | size_t *output_len, | 
|  | size_t output_size); | 
|  |  | 
|  | /** | 
|  | * \brief           Callback type: cancel external operation. | 
|  | * | 
|  | *                  This callback is called if an SSL connection is closed | 
|  | *                  while an asynchronous operation is in progress. Note that | 
|  | *                  this callback is not called if the | 
|  | *                  ::mbedtls_ssl_async_resume_t callback has run and has | 
|  | *                  returned a value other than | 
|  | *                  #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, since in that case | 
|  | *                  the asynchronous operation has already completed. | 
|  | * | 
|  | *                  This function may call mbedtls_ssl_get_async_operation_data() | 
|  | *                  to retrieve an operation context set by the start callback. | 
|  | * | 
|  | * \param ssl             The SSL connection instance. It should not be | 
|  | *                        modified. | 
|  | */ | 
|  | typedef void mbedtls_ssl_async_cancel_t(mbedtls_ssl_context *ssl); | 
|  | #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | 
|  |  | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) &&        \ | 
|  | !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) | 
|  | #define MBEDTLS_SSL_PEER_CERT_DIGEST_MAX_LEN  48 | 
|  | #if defined(MBEDTLS_MD_CAN_SHA256) | 
|  | #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA256 | 
|  | #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN  32 | 
|  | #elif defined(MBEDTLS_MD_CAN_SHA384) | 
|  | #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA384 | 
|  | #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN  48 | 
|  | #elif defined(MBEDTLS_MD_CAN_SHA1) | 
|  | #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_TYPE MBEDTLS_MD_SHA1 | 
|  | #define MBEDTLS_SSL_PEER_CERT_DIGEST_DFL_LEN  20 | 
|  | #else | 
|  | /* This is already checked in check_config.h, but be sure. */ | 
|  | #error "Bad configuration - need SHA-1, SHA-256 or SHA-512 enabled to compute digest of peer CRT." | 
|  | #endif | 
|  | #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED && | 
|  | !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ | 
|  |  | 
|  | typedef struct { | 
|  | unsigned char client_application_traffic_secret_N[MBEDTLS_TLS1_3_MD_MAX_SIZE]; | 
|  | unsigned char server_application_traffic_secret_N[MBEDTLS_TLS1_3_MD_MAX_SIZE]; | 
|  | unsigned char exporter_master_secret[MBEDTLS_TLS1_3_MD_MAX_SIZE]; | 
|  | unsigned char resumption_master_secret[MBEDTLS_TLS1_3_MD_MAX_SIZE]; | 
|  | } mbedtls_ssl_tls13_application_secrets; | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_SRTP) | 
|  |  | 
|  | #define MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH             255 | 
|  | #define MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH    4 | 
|  | /* | 
|  | * For code readability use a typedef for DTLS-SRTP profiles | 
|  | * | 
|  | * Use_srtp extension protection profiles values as defined in | 
|  | * http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml | 
|  | * | 
|  | * Reminder: if this list is expanded mbedtls_ssl_check_srtp_profile_value | 
|  | * must be updated too. | 
|  | */ | 
|  | #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80     ((uint16_t) 0x0001) | 
|  | #define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32     ((uint16_t) 0x0002) | 
|  | #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80          ((uint16_t) 0x0005) | 
|  | #define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32          ((uint16_t) 0x0006) | 
|  | /* This one is not iana defined, but for code readability. */ | 
|  | #define MBEDTLS_TLS_SRTP_UNSET                      ((uint16_t) 0x0000) | 
|  |  | 
|  | typedef uint16_t mbedtls_ssl_srtp_profile; | 
|  |  | 
|  | typedef struct mbedtls_dtls_srtp_info_t { | 
|  | /*! The SRTP profile that was negotiated. */ | 
|  | mbedtls_ssl_srtp_profile MBEDTLS_PRIVATE(chosen_dtls_srtp_profile); | 
|  | /*! The length of mki_value. */ | 
|  | uint16_t MBEDTLS_PRIVATE(mki_len); | 
|  | /*! The mki_value used, with max size of 256 bytes. */ | 
|  | unsigned char MBEDTLS_PRIVATE(mki_value)[MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH]; | 
|  | } | 
|  | mbedtls_dtls_srtp_info; | 
|  |  | 
|  | #endif /* MBEDTLS_SSL_DTLS_SRTP */ | 
|  |  | 
|  | /** Human-friendly representation of the (D)TLS protocol version. */ | 
|  | typedef enum { | 
|  | MBEDTLS_SSL_VERSION_UNKNOWN, /*!< Context not in use or version not yet negotiated. */ | 
|  | MBEDTLS_SSL_VERSION_TLS1_2 = 0x0303, /*!< (D)TLS 1.2 */ | 
|  | MBEDTLS_SSL_VERSION_TLS1_3 = 0x0304, /*!< (D)TLS 1.3 */ | 
|  | } mbedtls_ssl_protocol_version; | 
|  |  | 
|  | /* | 
|  | * This structure is used for storing current session data. | 
|  | * | 
|  | * Note: when changing this definition, we need to check and update: | 
|  | *  - in tests/suites/test_suite_ssl.function: | 
|  | *      ssl_populate_session() and ssl_serialize_session_save_load() | 
|  | *  - in library/ssl_tls.c: | 
|  | *      mbedtls_ssl_session_init() and mbedtls_ssl_session_free() | 
|  | *      mbedtls_ssl_session_save() and ssl_session_load() | 
|  | *      ssl_session_copy() | 
|  | */ | 
|  | struct mbedtls_ssl_session { | 
|  | #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) | 
|  | unsigned char MBEDTLS_PRIVATE(mfl_code);     /*!< MaxFragmentLength negotiated by peer */ | 
|  | #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ | 
|  |  | 
|  | unsigned char MBEDTLS_PRIVATE(exported); | 
|  |  | 
|  | /** TLS version negotiated in the session. Used if and when renegotiating | 
|  | *  or resuming a session instead of the configured minor TLS version. | 
|  | */ | 
|  | mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(tls_version); | 
|  |  | 
|  | #if defined(MBEDTLS_HAVE_TIME) | 
|  | mbedtls_time_t MBEDTLS_PRIVATE(start);       /*!< starting time      */ | 
|  | #endif | 
|  | int MBEDTLS_PRIVATE(ciphersuite);            /*!< chosen ciphersuite */ | 
|  | size_t MBEDTLS_PRIVATE(id_len);              /*!< session id length  */ | 
|  | unsigned char MBEDTLS_PRIVATE(id)[32];       /*!< session identifier */ | 
|  | unsigned char MBEDTLS_PRIVATE(master)[48];   /*!< the master secret  */ | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | #if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) | 
|  | mbedtls_x509_crt *MBEDTLS_PRIVATE(peer_cert);       /*!< peer X.509 cert chain */ | 
|  | #else /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ | 
|  | /*! The digest of the peer's end-CRT. This must be kept to detect CRT | 
|  | *  changes during renegotiation, mitigating the triple handshake attack. */ | 
|  | unsigned char *MBEDTLS_PRIVATE(peer_cert_digest); | 
|  | size_t MBEDTLS_PRIVATE(peer_cert_digest_len); | 
|  | mbedtls_md_type_t MBEDTLS_PRIVATE(peer_cert_digest_type); | 
|  | #endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */ | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  | uint32_t MBEDTLS_PRIVATE(verify_result);          /*!<  verification result     */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C) | 
|  | unsigned char *MBEDTLS_PRIVATE(ticket);      /*!< RFC 5077 session ticket */ | 
|  | size_t MBEDTLS_PRIVATE(ticket_len);          /*!< session ticket length   */ | 
|  | uint32_t MBEDTLS_PRIVATE(ticket_lifetime);   /*!< ticket lifetime hint    */ | 
|  | #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS) | 
|  | uint8_t MBEDTLS_PRIVATE(endpoint);          /*!< 0: client, 1: server */ | 
|  | uint8_t MBEDTLS_PRIVATE(ticket_flags);      /*!< Ticket flags */ | 
|  | uint32_t MBEDTLS_PRIVATE(ticket_age_add);               /*!< Randomly generated value used to obscure the age of the ticket */ | 
|  | uint8_t MBEDTLS_PRIVATE(resumption_key_len);            /*!< resumption_key length */ | 
|  | unsigned char MBEDTLS_PRIVATE(resumption_key)[MBEDTLS_SSL_TLS1_3_TICKET_RESUMPTION_KEY_LEN]; | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) && defined(MBEDTLS_SSL_CLI_C) | 
|  | char *MBEDTLS_PRIVATE(hostname);             /*!< host name binded with tickets */ | 
|  | #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION && MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_HAVE_TIME) && defined(MBEDTLS_SSL_CLI_C) | 
|  | mbedtls_time_t MBEDTLS_PRIVATE(ticket_received);        /*!< time ticket was received */ | 
|  | #endif /* MBEDTLS_HAVE_TIME && MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | #endif /*  MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_SESSION_TICKETS */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) | 
|  | int MBEDTLS_PRIVATE(encrypt_then_mac);       /*!< flag for EtM activation                */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) | 
|  | mbedtls_ssl_tls13_application_secrets MBEDTLS_PRIVATE(app_secrets); | 
|  | #endif | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * Identifiers for PRFs used in various versions of TLS. | 
|  | */ | 
|  | typedef enum { | 
|  | MBEDTLS_SSL_TLS_PRF_NONE, | 
|  | MBEDTLS_SSL_TLS_PRF_SHA384, | 
|  | MBEDTLS_SSL_TLS_PRF_SHA256, | 
|  | MBEDTLS_SSL_HKDF_EXPAND_SHA384, | 
|  | MBEDTLS_SSL_HKDF_EXPAND_SHA256 | 
|  | } | 
|  | mbedtls_tls_prf_types; | 
|  |  | 
|  | typedef enum { | 
|  | MBEDTLS_SSL_KEY_EXPORT_TLS12_MASTER_SECRET = 0, | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) | 
|  | MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_EARLY_SECRET, | 
|  | MBEDTLS_SSL_KEY_EXPORT_TLS1_3_EARLY_EXPORTER_SECRET, | 
|  | MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_HANDSHAKE_TRAFFIC_SECRET, | 
|  | MBEDTLS_SSL_KEY_EXPORT_TLS1_3_SERVER_HANDSHAKE_TRAFFIC_SECRET, | 
|  | MBEDTLS_SSL_KEY_EXPORT_TLS1_3_CLIENT_APPLICATION_TRAFFIC_SECRET, | 
|  | MBEDTLS_SSL_KEY_EXPORT_TLS1_3_SERVER_APPLICATION_TRAFFIC_SECRET, | 
|  | #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */ | 
|  | } mbedtls_ssl_key_export_type; | 
|  |  | 
|  | /** | 
|  | * \brief           Callback type: Export key alongside random values for | 
|  | *                                 session identification, and PRF for | 
|  | *                                 implementation of TLS key exporters. | 
|  | * | 
|  | * \param p_expkey   Context for the callback. | 
|  | * \param type       The type of the key that is being exported. | 
|  | * \param secret     The address of the buffer holding the secret | 
|  | *                   that's being exporterd. | 
|  | * \param secret_len The length of \p secret in bytes. | 
|  | * \param client_random The client random bytes. | 
|  | * \param server_random The server random bytes. | 
|  | * \param tls_prf_type The identifier for the PRF used in the handshake | 
|  | *                     to which the key belongs. | 
|  | */ | 
|  | typedef void mbedtls_ssl_export_keys_t(void *p_expkey, | 
|  | mbedtls_ssl_key_export_type type, | 
|  | const unsigned char *secret, | 
|  | size_t secret_len, | 
|  | const unsigned char client_random[32], | 
|  | const unsigned char server_random[32], | 
|  | mbedtls_tls_prf_types tls_prf_type); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief           Callback type: generic handshake callback | 
|  | * | 
|  | * \note            Callbacks may use user_data funcs to set/get app user data. | 
|  | *                  See \c mbedtls_ssl_get_user_data_p() | 
|  | *                      \c mbedtls_ssl_get_user_data_n() | 
|  | *                      \c mbedtls_ssl_conf_get_user_data_p() | 
|  | *                      \c mbedtls_ssl_conf_get_user_data_n() | 
|  | * | 
|  | * \param ssl       \c mbedtls_ssl_context on which the callback is run | 
|  | * | 
|  | * \return          The return value of the callback is 0 if successful, | 
|  | *                  or a specific MBEDTLS_ERR_XXX code, which will cause | 
|  | *                  the handshake to be aborted. | 
|  | */ | 
|  | typedef int (*mbedtls_ssl_hs_cb_t)(mbedtls_ssl_context *ssl); | 
|  | #endif | 
|  |  | 
|  | /* A type for storing user data in a library structure. | 
|  | * | 
|  | * The representation of type may change in future versions of the library. | 
|  | * Only the behaviors guaranteed by documented accessor functions are | 
|  | * guaranteed to remain stable. | 
|  | */ | 
|  | typedef union { | 
|  | uintptr_t n;                /* typically a handle to an associated object */ | 
|  | void *p;                    /* typically a pointer to extra data */ | 
|  | } mbedtls_ssl_user_data_t; | 
|  |  | 
|  | /** | 
|  | * SSL/TLS configuration to be shared between mbedtls_ssl_context structures. | 
|  | */ | 
|  | struct mbedtls_ssl_config { | 
|  | /* Group items mostly by size. This helps to reduce memory wasted to | 
|  | * padding. It also helps to keep smaller fields early in the structure, | 
|  | * so that elements tend to be in the 128-element direct access window | 
|  | * on Arm Thumb, which reduces the code size. */ | 
|  |  | 
|  | mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(max_tls_version);  /*!< max. TLS version used */ | 
|  | mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(min_tls_version);  /*!< min. TLS version used */ | 
|  |  | 
|  | /* | 
|  | * Flags (could be bit-fields to save RAM, but separate bytes make | 
|  | * the code smaller on architectures with an instruction for direct | 
|  | * byte access). | 
|  | */ | 
|  |  | 
|  | uint8_t MBEDTLS_PRIVATE(endpoint);      /*!< 0: client, 1: server               */ | 
|  | uint8_t MBEDTLS_PRIVATE(transport);     /*!< 0: stream (TLS), 1: datagram (DTLS)    */ | 
|  | uint8_t MBEDTLS_PRIVATE(authmode);      /*!< MBEDTLS_SSL_VERIFY_XXX             */ | 
|  | /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE          */ | 
|  | uint8_t MBEDTLS_PRIVATE(allow_legacy_renegotiation); /*!< MBEDTLS_LEGACY_XXX   */ | 
|  | #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) | 
|  | uint8_t MBEDTLS_PRIVATE(mfl_code);      /*!< desired fragment length indicator | 
|  | (MBEDTLS_SSL_MAX_FRAG_LEN_XXX) */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) | 
|  | uint8_t MBEDTLS_PRIVATE(encrypt_then_mac); /*!< negotiate encrypt-then-mac?    */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) | 
|  | uint8_t MBEDTLS_PRIVATE(extended_ms);   /*!< negotiate extended master secret?  */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) | 
|  | uint8_t MBEDTLS_PRIVATE(anti_replay);   /*!< detect and prevent replay?         */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_SSL_RENEGOTIATION) | 
|  | uint8_t MBEDTLS_PRIVATE(disable_renegotiation); /*!< disable renegotiation?     */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_SSL_SESSION_TICKETS) && \ | 
|  | defined(MBEDTLS_SSL_CLI_C) | 
|  | uint8_t MBEDTLS_PRIVATE(session_tickets);   /*!< use session tickets? */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SESSION_TICKETS) && \ | 
|  | defined(MBEDTLS_SSL_SRV_C) && \ | 
|  | defined(MBEDTLS_SSL_PROTO_TLS1_3) | 
|  | uint16_t MBEDTLS_PRIVATE(new_session_tickets_count);   /*!< number of NewSessionTicket */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | uint8_t MBEDTLS_PRIVATE(cert_req_ca_list);  /*!< enable sending CA list in | 
|  | Certificate Request messages? */ | 
|  | uint8_t MBEDTLS_PRIVATE(respect_cli_pref);  /*!< pick the ciphersuite according to | 
|  | the client's preferences rather | 
|  | than ours? */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | 
|  | uint8_t MBEDTLS_PRIVATE(ignore_unexpected_cid); /*!< Should DTLS record with | 
|  | *   unexpected CID | 
|  | *   lead to failure? */ | 
|  | #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | 
|  | #if defined(MBEDTLS_SSL_DTLS_SRTP) | 
|  | uint8_t MBEDTLS_PRIVATE(dtls_srtp_mki_support); /* support having mki_value | 
|  | in the use_srtp extension? */ | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * Pointers | 
|  | */ | 
|  |  | 
|  | /** Allowed ciphersuites for (D)TLS 1.2 (0-terminated)                  */ | 
|  | const int *MBEDTLS_PRIVATE(ciphersuite_list); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) | 
|  | /** Allowed TLS 1.3 key exchange modes.                                 */ | 
|  | int MBEDTLS_PRIVATE(tls13_kex_modes); | 
|  | #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */ | 
|  |  | 
|  | /** Callback for printing debug output                                  */ | 
|  | void(*MBEDTLS_PRIVATE(f_dbg))(void *, int, const char *, int, const char *); | 
|  | void *MBEDTLS_PRIVATE(p_dbg);                    /*!< context for the debug function     */ | 
|  |  | 
|  | /** Callback for getting (pseudo-)random numbers                        */ | 
|  | int(*MBEDTLS_PRIVATE(f_rng))(void *, unsigned char *, size_t); | 
|  | void *MBEDTLS_PRIVATE(p_rng);                    /*!< context for the RNG function       */ | 
|  |  | 
|  | /** Callback to retrieve a session from the cache                       */ | 
|  | mbedtls_ssl_cache_get_t *MBEDTLS_PRIVATE(f_get_cache); | 
|  | /** Callback to store a session into the cache                          */ | 
|  | mbedtls_ssl_cache_set_t *MBEDTLS_PRIVATE(f_set_cache); | 
|  | void *MBEDTLS_PRIVATE(p_cache);                  /*!< context for cache callbacks        */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) | 
|  | /** Callback for setting cert according to SNI extension                */ | 
|  | int(*MBEDTLS_PRIVATE(f_sni))(void *, mbedtls_ssl_context *, const unsigned char *, size_t); | 
|  | void *MBEDTLS_PRIVATE(p_sni);                    /*!< context for SNI callback           */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | /** Callback to customize X.509 certificate chain verification          */ | 
|  | int(*MBEDTLS_PRIVATE(f_vrfy))(void *, mbedtls_x509_crt *, int, uint32_t *); | 
|  | void *MBEDTLS_PRIVATE(p_vrfy);                   /*!< context for X.509 verify calllback */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED) | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** Callback to retrieve PSK key from identity                          */ | 
|  | int(*MBEDTLS_PRIVATE(f_psk))(void *, mbedtls_ssl_context *, const unsigned char *, size_t); | 
|  | void *MBEDTLS_PRIVATE(p_psk);                    /*!< context for PSK callback           */ | 
|  | #endif | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) | 
|  | /** Callback to create & write a cookie for ClientHello verification    */ | 
|  | int(*MBEDTLS_PRIVATE(f_cookie_write))(void *, unsigned char **, unsigned char *, | 
|  | const unsigned char *, size_t); | 
|  | /** Callback to verify validity of a ClientHello cookie                 */ | 
|  | int(*MBEDTLS_PRIVATE(f_cookie_check))(void *, const unsigned char *, size_t, | 
|  | const unsigned char *, size_t); | 
|  | void *MBEDTLS_PRIVATE(p_cookie);                 /*!< context for the cookie callbacks   */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C) | 
|  | /** Callback to create & write a session ticket                         */ | 
|  | int(*MBEDTLS_PRIVATE(f_ticket_write))(void *, const mbedtls_ssl_session *, | 
|  | unsigned char *, const unsigned char *, size_t *, | 
|  | uint32_t *); | 
|  | /** Callback to parse a session ticket into a session structure         */ | 
|  | int(*MBEDTLS_PRIVATE(f_ticket_parse))(void *, mbedtls_ssl_session *, unsigned char *, size_t); | 
|  | void *MBEDTLS_PRIVATE(p_ticket);                 /*!< context for the ticket callbacks   */ | 
|  | #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */ | 
|  | #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | 
|  | size_t MBEDTLS_PRIVATE(cid_len); /*!< The length of CIDs for incoming DTLS records.      */ | 
|  | #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | const mbedtls_x509_crt_profile *MBEDTLS_PRIVATE(cert_profile); /*!< verification profile */ | 
|  | mbedtls_ssl_key_cert *MBEDTLS_PRIVATE(key_cert); /*!< own certificate/key pair(s)        */ | 
|  | mbedtls_x509_crt *MBEDTLS_PRIVATE(ca_chain);     /*!< trusted CAs                        */ | 
|  | mbedtls_x509_crl *MBEDTLS_PRIVATE(ca_crl);       /*!< trusted CAs CRLs                   */ | 
|  | #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK) | 
|  | mbedtls_x509_crt_ca_cb_t MBEDTLS_PRIVATE(f_ca_cb); | 
|  | void *MBEDTLS_PRIVATE(p_ca_cb); | 
|  | #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */ | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | mbedtls_ssl_async_sign_t *MBEDTLS_PRIVATE(f_async_sign_start); /*!< start asynchronous signature operation */ | 
|  | mbedtls_ssl_async_decrypt_t *MBEDTLS_PRIVATE(f_async_decrypt_start); /*!< start asynchronous decryption operation */ | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  | mbedtls_ssl_async_resume_t *MBEDTLS_PRIVATE(f_async_resume); /*!< resume asynchronous operation */ | 
|  | mbedtls_ssl_async_cancel_t *MBEDTLS_PRIVATE(f_async_cancel); /*!< cancel asynchronous operation */ | 
|  | void *MBEDTLS_PRIVATE(p_async_config_data); /*!< Configuration data set by mbedtls_ssl_conf_async_private_cb(). */ | 
|  | #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED) | 
|  |  | 
|  | #if !defined(MBEDTLS_DEPRECATED_REMOVED) | 
|  | const int *MBEDTLS_PRIVATE(sig_hashes);         /*!< allowed signature hashes           */ | 
|  | #endif | 
|  | const uint16_t *MBEDTLS_PRIVATE(sig_algs);      /*!< allowed signature algorithms       */ | 
|  | #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */ | 
|  |  | 
|  | #if defined(MBEDTLS_ECP_LIGHT) && !defined(MBEDTLS_DEPRECATED_REMOVED) | 
|  | const mbedtls_ecp_group_id *MBEDTLS_PRIVATE(curve_list); /*!< allowed curves             */ | 
|  | #endif | 
|  |  | 
|  | const uint16_t *MBEDTLS_PRIVATE(group_list);     /*!< allowed IANA NamedGroups */ | 
|  |  | 
|  | #if defined(MBEDTLS_DHM_C) | 
|  | mbedtls_mpi MBEDTLS_PRIVATE(dhm_P);              /*!< prime modulus for DHM              */ | 
|  | mbedtls_mpi MBEDTLS_PRIVATE(dhm_G);              /*!< generator for DHM                  */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED) | 
|  |  | 
|  | #if defined(MBEDTLS_USE_PSA_CRYPTO) | 
|  | mbedtls_svc_key_id_t MBEDTLS_PRIVATE(psk_opaque); /*!< PSA key slot holding opaque PSK. This field | 
|  | *   should only be set via | 
|  | *   mbedtls_ssl_conf_psk_opaque(). | 
|  | *   If either no PSK or a raw PSK have been | 
|  | *   configured, this has value \c 0. | 
|  | */ | 
|  | #endif /* MBEDTLS_USE_PSA_CRYPTO */ | 
|  | unsigned char *MBEDTLS_PRIVATE(psk);      /*!< The raw pre-shared key. This field should | 
|  | *   only be set via mbedtls_ssl_conf_psk(). | 
|  | *   If either no PSK or an opaque PSK | 
|  | *   have been configured, this has value NULL. */ | 
|  | size_t         MBEDTLS_PRIVATE(psk_len);  /*!< The length of the raw pre-shared key. | 
|  | *   This field should only be set via | 
|  | *   mbedtls_ssl_conf_psk(). | 
|  | *   Its value is non-zero if and only if | 
|  | *   \c psk is not \c NULL. */ | 
|  |  | 
|  | unsigned char *MBEDTLS_PRIVATE(psk_identity);    /*!< The PSK identity for PSK negotiation. | 
|  | *   This field should only be set via | 
|  | *   mbedtls_ssl_conf_psk(). | 
|  | *   This is set if and only if either | 
|  | *   \c psk or \c psk_opaque are set. */ | 
|  | size_t         MBEDTLS_PRIVATE(psk_identity_len);/*!< The length of PSK identity. | 
|  | *   This field should only be set via | 
|  | *   mbedtls_ssl_conf_psk(). | 
|  | *   Its value is non-zero if and only if | 
|  | *   \c psk is not \c NULL or \c psk_opaque | 
|  | *   is not \c 0. */ | 
|  | #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_EARLY_DATA) | 
|  | int MBEDTLS_PRIVATE(early_data_enabled);     /*!< Early data enablement: | 
|  | *   - MBEDTLS_SSL_EARLY_DATA_DISABLED, | 
|  | *   - MBEDTLS_SSL_EARLY_DATA_ENABLED */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /* The maximum amount of 0-RTT data. RFC 8446 section 4.6.1 */ | 
|  | uint32_t MBEDTLS_PRIVATE(max_early_data_size); | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | #endif /* MBEDTLS_SSL_EARLY_DATA */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_ALPN) | 
|  | const char **MBEDTLS_PRIVATE(alpn_list);         /*!< ordered list of protocols          */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_SRTP) | 
|  | /*! ordered list of supported srtp profile */ | 
|  | const mbedtls_ssl_srtp_profile *MBEDTLS_PRIVATE(dtls_srtp_profile_list); | 
|  | /*! number of supported profiles */ | 
|  | size_t MBEDTLS_PRIVATE(dtls_srtp_profile_list_len); | 
|  | #endif /* MBEDTLS_SSL_DTLS_SRTP */ | 
|  |  | 
|  | /* | 
|  | * Numerical settings (int) | 
|  | */ | 
|  |  | 
|  | uint32_t MBEDTLS_PRIVATE(read_timeout);          /*!< timeout for mbedtls_ssl_read (ms)  */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_DTLS) | 
|  | uint32_t MBEDTLS_PRIVATE(hs_timeout_min);        /*!< initial value of the handshake | 
|  | retransmission timeout (ms)        */ | 
|  | uint32_t MBEDTLS_PRIVATE(hs_timeout_max);        /*!< maximum value of the handshake | 
|  | retransmission timeout (ms)        */ | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_RENEGOTIATION) | 
|  | int MBEDTLS_PRIVATE(renego_max_records);         /*!< grace period for renegotiation     */ | 
|  | unsigned char MBEDTLS_PRIVATE(renego_period)[8]; /*!< value of the record counters | 
|  | that triggers renegotiation        */ | 
|  | #endif | 
|  |  | 
|  | unsigned int MBEDTLS_PRIVATE(badmac_limit);      /*!< limit of records with a bad MAC    */ | 
|  |  | 
|  | #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C) | 
|  | unsigned int MBEDTLS_PRIVATE(dhm_min_bitlen);    /*!< min. bit length of the DHM prime   */ | 
|  | #endif | 
|  |  | 
|  | /** User data pointer or handle. | 
|  | * | 
|  | * The library sets this to \p 0 when creating a context and does not | 
|  | * access it afterwards. | 
|  | */ | 
|  | mbedtls_ssl_user_data_t MBEDTLS_PRIVATE(user_data); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | mbedtls_ssl_hs_cb_t MBEDTLS_PRIVATE(f_cert_cb);  /*!< certificate selection callback */ | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED) | 
|  | const mbedtls_x509_crt *MBEDTLS_PRIVATE(dn_hints);/*!< acceptable client cert issuers    */ | 
|  | #endif | 
|  | }; | 
|  |  | 
|  | struct mbedtls_ssl_context { | 
|  | const mbedtls_ssl_config *MBEDTLS_PRIVATE(conf); /*!< configuration information          */ | 
|  |  | 
|  | /* | 
|  | * Miscellaneous | 
|  | */ | 
|  | int MBEDTLS_PRIVATE(state);                  /*!< SSL handshake: current state     */ | 
|  | #if defined(MBEDTLS_SSL_RENEGOTIATION) | 
|  | int MBEDTLS_PRIVATE(renego_status);          /*!< Initial, in progress, pending?   */ | 
|  | int MBEDTLS_PRIVATE(renego_records_seen);    /*!< Records since renego request, or with DTLS, | 
|  | number of retransmissions of request if | 
|  | renego_max_records is < 0           */ | 
|  | #endif /* MBEDTLS_SSL_RENEGOTIATION */ | 
|  |  | 
|  | /** | 
|  | *  Maximum TLS version to be negotiated, then negotiated TLS version. | 
|  | * | 
|  | *  It is initialized as the configured maximum TLS version to be | 
|  | *  negotiated by mbedtls_ssl_setup(). | 
|  | * | 
|  | *  When renegotiating or resuming a session, it is overwritten in the | 
|  | *  ClientHello writing preparation stage with the previously negotiated | 
|  | *  TLS version. | 
|  | * | 
|  | *  On client side, it is updated to the TLS version selected by the server | 
|  | *  for the handshake when the ServerHello is received. | 
|  | * | 
|  | *  On server side, it is updated to the TLS version the server selects for | 
|  | *  the handshake when the ClientHello is received. | 
|  | */ | 
|  | mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(tls_version); | 
|  |  | 
|  | unsigned MBEDTLS_PRIVATE(badmac_seen);       /*!< records with a bad MAC received    */ | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | /** Callback to customize X.509 certificate chain verification          */ | 
|  | int(*MBEDTLS_PRIVATE(f_vrfy))(void *, mbedtls_x509_crt *, int, uint32_t *); | 
|  | void *MBEDTLS_PRIVATE(p_vrfy);                   /*!< context for X.509 verify callback */ | 
|  | #endif | 
|  |  | 
|  | mbedtls_ssl_send_t *MBEDTLS_PRIVATE(f_send); /*!< Callback for network send */ | 
|  | mbedtls_ssl_recv_t *MBEDTLS_PRIVATE(f_recv); /*!< Callback for network receive */ | 
|  | mbedtls_ssl_recv_timeout_t *MBEDTLS_PRIVATE(f_recv_timeout); | 
|  | /*!< Callback for network receive with timeout */ | 
|  |  | 
|  | void *MBEDTLS_PRIVATE(p_bio);                /*!< context for I/O operations   */ | 
|  |  | 
|  | /* | 
|  | * Session layer | 
|  | */ | 
|  | mbedtls_ssl_session *MBEDTLS_PRIVATE(session_in);            /*!<  current session data (in)   */ | 
|  | mbedtls_ssl_session *MBEDTLS_PRIVATE(session_out);           /*!<  current session data (out)  */ | 
|  | mbedtls_ssl_session *MBEDTLS_PRIVATE(session);               /*!<  negotiated session data     */ | 
|  | mbedtls_ssl_session *MBEDTLS_PRIVATE(session_negotiate);     /*!<  session data in negotiation */ | 
|  |  | 
|  | mbedtls_ssl_handshake_params *MBEDTLS_PRIVATE(handshake);    /*!<  params required only during | 
|  | the handshake process        */ | 
|  |  | 
|  | /* | 
|  | * Record layer transformations | 
|  | */ | 
|  | mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_in);        /*!<  current transform params (in) | 
|  | *    This is always a reference, | 
|  | *    never an owning pointer.        */ | 
|  | mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_out);       /*!<  current transform params (out) | 
|  | *    This is always a reference, | 
|  | *    never an owning pointer.        */ | 
|  | mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform);           /*!<  negotiated transform params | 
|  | *    This pointer owns the transform | 
|  | *    it references.                  */ | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_2) | 
|  | mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_negotiate); /*!<  transform params in negotiation | 
|  | *    This pointer owns the transform | 
|  | *    it references.                  */ | 
|  | #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) | 
|  | /*! The application data transform in TLS 1.3. | 
|  | *  This pointer owns the transform it references. */ | 
|  | mbedtls_ssl_transform *MBEDTLS_PRIVATE(transform_application); | 
|  | #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */ | 
|  |  | 
|  | /* | 
|  | * Timers | 
|  | */ | 
|  | void *MBEDTLS_PRIVATE(p_timer);              /*!< context for the timer callbacks */ | 
|  |  | 
|  | mbedtls_ssl_set_timer_t *MBEDTLS_PRIVATE(f_set_timer);       /*!< set timer callback */ | 
|  | mbedtls_ssl_get_timer_t *MBEDTLS_PRIVATE(f_get_timer);       /*!< get timer callback */ | 
|  |  | 
|  | /* | 
|  | * Record layer (incoming data) | 
|  | */ | 
|  | unsigned char *MBEDTLS_PRIVATE(in_buf);      /*!< input buffer                     */ | 
|  | unsigned char *MBEDTLS_PRIVATE(in_ctr);      /*!< 64-bit incoming message counter | 
|  | TLS: maintained by us | 
|  | DTLS: read from peer             */ | 
|  | unsigned char *MBEDTLS_PRIVATE(in_hdr);      /*!< start of record header           */ | 
|  | #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | 
|  | unsigned char *MBEDTLS_PRIVATE(in_cid);      /*!< The start of the CID; | 
|  | *   (the end is marked by in_len).   */ | 
|  | #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | 
|  | unsigned char *MBEDTLS_PRIVATE(in_len);      /*!< two-bytes message length field   */ | 
|  | unsigned char *MBEDTLS_PRIVATE(in_iv);       /*!< ivlen-byte IV                    */ | 
|  | unsigned char *MBEDTLS_PRIVATE(in_msg);      /*!< message contents (in_iv+ivlen)   */ | 
|  | unsigned char *MBEDTLS_PRIVATE(in_offt);     /*!< read offset in application data  */ | 
|  |  | 
|  | int MBEDTLS_PRIVATE(in_msgtype);             /*!< record header: message type      */ | 
|  | size_t MBEDTLS_PRIVATE(in_msglen);           /*!< record header: message length    */ | 
|  | size_t MBEDTLS_PRIVATE(in_left);             /*!< amount of data read so far       */ | 
|  | #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH) | 
|  | size_t MBEDTLS_PRIVATE(in_buf_len);          /*!< length of input buffer           */ | 
|  | #endif | 
|  | #if defined(MBEDTLS_SSL_PROTO_DTLS) | 
|  | uint16_t MBEDTLS_PRIVATE(in_epoch);          /*!< DTLS epoch for incoming records  */ | 
|  | size_t MBEDTLS_PRIVATE(next_record_offset);  /*!< offset of the next record in datagram | 
|  | (equal to in_left if none)       */ | 
|  | #endif /* MBEDTLS_SSL_PROTO_DTLS */ | 
|  | #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) | 
|  | uint64_t MBEDTLS_PRIVATE(in_window_top);     /*!< last validated record seq_num    */ | 
|  | uint64_t MBEDTLS_PRIVATE(in_window);         /*!< bitmask for replay detection     */ | 
|  | #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */ | 
|  |  | 
|  | size_t MBEDTLS_PRIVATE(in_hslen);            /*!< current handshake message length, | 
|  | including the handshake header   */ | 
|  | int MBEDTLS_PRIVATE(nb_zero);                /*!< # of 0-length encrypted messages */ | 
|  |  | 
|  | int MBEDTLS_PRIVATE(keep_current_message);   /*!< drop or reuse current message | 
|  | on next call to record layer? */ | 
|  |  | 
|  | /* The following three variables indicate if and, if yes, | 
|  | * what kind of alert is pending to be sent. | 
|  | */ | 
|  | unsigned char MBEDTLS_PRIVATE(send_alert);   /*!< Determines if a fatal alert | 
|  | should be sent. Values: | 
|  | - \c 0 , no alert is to be sent. | 
|  | - \c 1 , alert is to be sent. */ | 
|  | unsigned char MBEDTLS_PRIVATE(alert_type);   /*!< Type of alert if send_alert | 
|  | != 0 */ | 
|  | int MBEDTLS_PRIVATE(alert_reason);           /*!< The error code to be returned | 
|  | to the user once the fatal alert | 
|  | has been sent. */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_DTLS) | 
|  | uint8_t MBEDTLS_PRIVATE(disable_datagram_packing);  /*!< Disable packing multiple records | 
|  | *   within a single datagram.  */ | 
|  | #endif /* MBEDTLS_SSL_PROTO_DTLS */ | 
|  |  | 
|  | /* | 
|  | * Record layer (outgoing data) | 
|  | */ | 
|  | unsigned char *MBEDTLS_PRIVATE(out_buf);     /*!< output buffer                    */ | 
|  | unsigned char *MBEDTLS_PRIVATE(out_ctr);     /*!< 64-bit outgoing message counter  */ | 
|  | unsigned char *MBEDTLS_PRIVATE(out_hdr);     /*!< start of record header           */ | 
|  | #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | 
|  | unsigned char *MBEDTLS_PRIVATE(out_cid);     /*!< The start of the CID; | 
|  | *   (the end is marked by in_len).   */ | 
|  | #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | 
|  | unsigned char *MBEDTLS_PRIVATE(out_len);     /*!< two-bytes message length field   */ | 
|  | unsigned char *MBEDTLS_PRIVATE(out_iv);      /*!< ivlen-byte IV                    */ | 
|  | unsigned char *MBEDTLS_PRIVATE(out_msg);     /*!< message contents (out_iv+ivlen)  */ | 
|  |  | 
|  | int MBEDTLS_PRIVATE(out_msgtype);            /*!< record header: message type      */ | 
|  | size_t MBEDTLS_PRIVATE(out_msglen);          /*!< record header: message length    */ | 
|  | size_t MBEDTLS_PRIVATE(out_left);            /*!< amount of data not yet written   */ | 
|  | #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH) | 
|  | size_t MBEDTLS_PRIVATE(out_buf_len);         /*!< length of output buffer          */ | 
|  | #endif | 
|  |  | 
|  | unsigned char MBEDTLS_PRIVATE(cur_out_ctr)[MBEDTLS_SSL_SEQUENCE_NUMBER_LEN]; /*!<  Outgoing record sequence  number. */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_DTLS) | 
|  | uint16_t MBEDTLS_PRIVATE(mtu);               /*!< path mtu, used to fragment outgoing messages */ | 
|  | #endif /* MBEDTLS_SSL_PROTO_DTLS */ | 
|  |  | 
|  | /* | 
|  | * User settings | 
|  | */ | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | char *MBEDTLS_PRIVATE(hostname);             /*!< expected peer CN for verification | 
|  | (and SNI if available)                 */ | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_ALPN) | 
|  | const char *MBEDTLS_PRIVATE(alpn_chosen);    /*!<  negotiated protocol                   */ | 
|  | #endif /* MBEDTLS_SSL_ALPN */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_SRTP) | 
|  | /* | 
|  | * use_srtp extension | 
|  | */ | 
|  | mbedtls_dtls_srtp_info MBEDTLS_PRIVATE(dtls_srtp_info); | 
|  | #endif /* MBEDTLS_SSL_DTLS_SRTP */ | 
|  |  | 
|  | /* | 
|  | * Information for DTLS hello verify | 
|  | */ | 
|  | #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) | 
|  | unsigned char  *MBEDTLS_PRIVATE(cli_id);         /*!<  transport-level ID of the client  */ | 
|  | size_t          MBEDTLS_PRIVATE(cli_id_len);     /*!<  length of cli_id                  */ | 
|  | #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | /* | 
|  | * Secure renegotiation | 
|  | */ | 
|  | /* needed to know when to send extension on server */ | 
|  | int MBEDTLS_PRIVATE(secure_renegotiation);           /*!<  does peer support legacy or | 
|  | secure renegotiation           */ | 
|  | #if defined(MBEDTLS_SSL_RENEGOTIATION) | 
|  | size_t MBEDTLS_PRIVATE(verify_data_len);             /*!<  length of verify data stored   */ | 
|  | char MBEDTLS_PRIVATE(own_verify_data)[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!<  previous handshake verify data */ | 
|  | char MBEDTLS_PRIVATE(peer_verify_data)[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!<  previous handshake verify data */ | 
|  | #endif /* MBEDTLS_SSL_RENEGOTIATION */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | 
|  | /* CID configuration to use in subsequent handshakes. */ | 
|  |  | 
|  | /*! The next incoming CID, chosen by the user and applying to | 
|  | *  all subsequent handshakes. This may be different from the | 
|  | *  CID currently used in case the user has re-configured the CID | 
|  | *  after an initial handshake. */ | 
|  | unsigned char MBEDTLS_PRIVATE(own_cid)[MBEDTLS_SSL_CID_IN_LEN_MAX]; | 
|  | uint8_t MBEDTLS_PRIVATE(own_cid_len);   /*!< The length of \c own_cid. */ | 
|  | uint8_t MBEDTLS_PRIVATE(negotiate_cid); /*!< This indicates whether the CID extension should | 
|  | *   be negotiated in the next handshake or not. | 
|  | *   Possible values are #MBEDTLS_SSL_CID_ENABLED | 
|  | *   and #MBEDTLS_SSL_CID_DISABLED. */ | 
|  | #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C) | 
|  | int MBEDTLS_PRIVATE(early_data_status); | 
|  | #endif /* MBEDTLS_SSL_EARLY_DATA && MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | /** Callback to export key block and master secret                      */ | 
|  | mbedtls_ssl_export_keys_t *MBEDTLS_PRIVATE(f_export_keys); | 
|  | void *MBEDTLS_PRIVATE(p_export_keys);            /*!< context for key export callback    */ | 
|  |  | 
|  | /** User data pointer or handle. | 
|  | * | 
|  | * The library sets this to \p 0 when creating a context and does not | 
|  | * access it afterwards. | 
|  | * | 
|  | * \warning Serializing and restoring an SSL context with | 
|  | *          mbedtls_ssl_context_save() and mbedtls_ssl_context_load() | 
|  | *          does not currently restore the user data. | 
|  | */ | 
|  | mbedtls_ssl_user_data_t MBEDTLS_PRIVATE(user_data); | 
|  | }; | 
|  |  | 
|  | /** | 
|  | * \brief               Return the name of the ciphersuite associated with the | 
|  | *                      given ID | 
|  | * | 
|  | * \param ciphersuite_id SSL ciphersuite ID | 
|  | * | 
|  | * \return              a string containing the ciphersuite name | 
|  | */ | 
|  | const char *mbedtls_ssl_get_ciphersuite_name(const int ciphersuite_id); | 
|  |  | 
|  | /** | 
|  | * \brief               Return the ID of the ciphersuite associated with the | 
|  | *                      given name | 
|  | * | 
|  | * \param ciphersuite_name SSL ciphersuite name | 
|  | * | 
|  | * \return              the ID with the ciphersuite or 0 if not found | 
|  | */ | 
|  | int mbedtls_ssl_get_ciphersuite_id(const char *ciphersuite_name); | 
|  |  | 
|  | /** | 
|  | * \brief          Initialize an SSL context | 
|  | *                 Just makes the context ready for mbedtls_ssl_setup() or | 
|  | *                 mbedtls_ssl_free() | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | */ | 
|  | void mbedtls_ssl_init(mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Set up an SSL context for use | 
|  | * | 
|  | * \note           No copy of the configuration context is made, it can be | 
|  | *                 shared by many mbedtls_ssl_context structures. | 
|  | * | 
|  | * \warning        The conf structure will be accessed during the session. | 
|  | *                 It must not be modified or freed as long as the session | 
|  | *                 is active. | 
|  | * | 
|  | * \warning        This function must be called exactly once per context. | 
|  | *                 Calling mbedtls_ssl_setup again is not supported, even | 
|  | *                 if no session is active. | 
|  | * | 
|  | * \note           If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto | 
|  | *                 subsystem must have been initialized by calling | 
|  | *                 psa_crypto_init() before calling this function. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param conf     SSL configuration to use | 
|  | * | 
|  | * \return         0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED if | 
|  | *                 memory allocation failed | 
|  | */ | 
|  | int mbedtls_ssl_setup(mbedtls_ssl_context *ssl, | 
|  | const mbedtls_ssl_config *conf); | 
|  |  | 
|  | /** | 
|  | * \brief          Reset an already initialized SSL context for re-use | 
|  | *                 while retaining application-set variables, function | 
|  | *                 pointers and data. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \return         0 if successful, or MBEDTLS_ERR_SSL_ALLOC_FAILED or | 
|  | MBEDTLS_ERR_SSL_HW_ACCEL_FAILED | 
|  | */ | 
|  | int mbedtls_ssl_session_reset(mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Set the current endpoint type | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param endpoint must be MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER | 
|  | */ | 
|  | void mbedtls_ssl_conf_endpoint(mbedtls_ssl_config *conf, int endpoint); | 
|  |  | 
|  | /** | 
|  | * \brief           Set the transport type (TLS or DTLS). | 
|  | *                  Default: TLS | 
|  | * | 
|  | * \note            For DTLS, you must either provide a recv callback that | 
|  | *                  doesn't block, or one that handles timeouts, see | 
|  | *                  \c mbedtls_ssl_set_bio(). You also need to provide timer | 
|  | *                  callbacks with \c mbedtls_ssl_set_timer_cb(). | 
|  | * | 
|  | * \param conf      SSL configuration | 
|  | * \param transport transport type: | 
|  | *                  MBEDTLS_SSL_TRANSPORT_STREAM for TLS, | 
|  | *                  MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS. | 
|  | */ | 
|  | void mbedtls_ssl_conf_transport(mbedtls_ssl_config *conf, int transport); | 
|  |  | 
|  | /** | 
|  | * \brief          Set the certificate verification mode | 
|  | *                 Default: NONE on server, REQUIRED on client | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param authmode can be: | 
|  | * | 
|  | *  MBEDTLS_SSL_VERIFY_NONE:      peer certificate is not checked | 
|  | *                        (default on server) | 
|  | *                        (insecure on client) | 
|  | * | 
|  | *  MBEDTLS_SSL_VERIFY_OPTIONAL:  peer certificate is checked, however the | 
|  | *                        handshake continues even if verification failed; | 
|  | *                        mbedtls_ssl_get_verify_result() can be called after the | 
|  | *                        handshake is complete. | 
|  | * | 
|  | *  MBEDTLS_SSL_VERIFY_REQUIRED:  peer *must* present a valid certificate, | 
|  | *                        handshake is aborted if verification failed. | 
|  | *                        (default on client) | 
|  | * | 
|  | * \note On client, MBEDTLS_SSL_VERIFY_REQUIRED is the recommended mode. | 
|  | * With MBEDTLS_SSL_VERIFY_OPTIONAL, the user needs to call mbedtls_ssl_get_verify_result() at | 
|  | * the right time(s), which may not be obvious, while REQUIRED always perform | 
|  | * the verification as soon as possible. For example, REQUIRED was protecting | 
|  | * against the "triple handshake" attack even before it was found. | 
|  | */ | 
|  | void mbedtls_ssl_conf_authmode(mbedtls_ssl_config *conf, int authmode); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_EARLY_DATA) | 
|  | /** | 
|  | * \brief    Set the early data mode | 
|  | *           Default: disabled on server and client | 
|  | * | 
|  | * \param conf   The SSL configuration to use. | 
|  | * \param early_data_enabled can be: | 
|  | * | 
|  | *  MBEDTLS_SSL_EARLY_DATA_DISABLED:  early data functionality is disabled | 
|  | *                                    This is the default on client and server. | 
|  | * | 
|  | *  MBEDTLS_SSL_EARLY_DATA_ENABLED:  early data functionality is enabled and | 
|  | *                        may be negotiated in the handshake. Application using | 
|  | *                        early data functionality needs to be aware of the | 
|  | *                        lack of replay protection of the early data application | 
|  | *                        payloads. | 
|  | * | 
|  | * \warning This interface is experimental and may change without notice. | 
|  | * | 
|  | */ | 
|  | void mbedtls_ssl_tls13_conf_early_data(mbedtls_ssl_config *conf, | 
|  | int early_data_enabled); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief Set the maximum amount of 0-RTT data in bytes | 
|  | *        Default:  #MBEDTLS_SSL_MAX_EARLY_DATA_SIZE | 
|  | * | 
|  | *        This function sets the value of the max_early_data_size | 
|  | *        field of the early data indication extension included in | 
|  | *        the NewSessionTicket messages that the server may send. | 
|  | * | 
|  | *        The value defines the maximum amount of 0-RTT data | 
|  | *        in bytes that a client will be allowed to send when using | 
|  | *        one of the tickets defined by the NewSessionTicket messages. | 
|  | * | 
|  | * \note When resuming a session using a ticket, if the server receives more | 
|  | *       early data than allowed for the ticket, it terminates the connection. | 
|  | *       The maximum amount of 0-RTT data should thus be large enough | 
|  | *       to allow a minimum of early data to be exchanged. | 
|  | * | 
|  | * \param[in] conf                  The SSL configuration to use. | 
|  | * \param[in] max_early_data_size   The maximum amount of 0-RTT data. | 
|  | * | 
|  | * \warning This interface is experimental and may change without notice. | 
|  | * | 
|  | */ | 
|  | void mbedtls_ssl_tls13_conf_max_early_data_size( | 
|  | mbedtls_ssl_config *conf, uint32_t max_early_data_size); | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | #endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_EARLY_DATA */ | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | /** | 
|  | * \brief          Set the verification callback (Optional). | 
|  | * | 
|  | *                 If set, the provided verify callback is called for each | 
|  | *                 certificate in the peer's CRT chain, including the trusted | 
|  | *                 root. For more information, please see the documentation of | 
|  | *                 \c mbedtls_x509_crt_verify(). | 
|  | * | 
|  | * \note           For per context callbacks and contexts, please use | 
|  | *                 mbedtls_ssl_set_verify() instead. | 
|  | * | 
|  | * \param conf     The SSL configuration to use. | 
|  | * \param f_vrfy   The verification callback to use during CRT verification. | 
|  | * \param p_vrfy   The opaque context to be passed to the callback. | 
|  | */ | 
|  | void mbedtls_ssl_conf_verify(mbedtls_ssl_config *conf, | 
|  | int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *), | 
|  | void *p_vrfy); | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set the random number generator callback | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param f_rng    RNG function (mandatory) | 
|  | * \param p_rng    RNG parameter | 
|  | */ | 
|  | void mbedtls_ssl_conf_rng(mbedtls_ssl_config *conf, | 
|  | int (*f_rng)(void *, unsigned char *, size_t), | 
|  | void *p_rng); | 
|  |  | 
|  | /** | 
|  | * \brief          Set the debug callback | 
|  | * | 
|  | *                 The callback has the following argument: | 
|  | *                 void *           opaque context for the callback | 
|  | *                 int              debug level | 
|  | *                 const char *     file name | 
|  | *                 int              line number | 
|  | *                 const char *     message | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param f_dbg    debug function | 
|  | * \param p_dbg    debug parameter | 
|  | */ | 
|  | void mbedtls_ssl_conf_dbg(mbedtls_ssl_config *conf, | 
|  | void (*f_dbg)(void *, int, const char *, int, const char *), | 
|  | void  *p_dbg); | 
|  |  | 
|  | /** | 
|  | * \brief          Return the SSL configuration structure associated | 
|  | *                 with the given SSL context. | 
|  | * | 
|  | * \note           The pointer returned by this function is guaranteed to | 
|  | *                 remain valid until the context is freed. | 
|  | * | 
|  | * \param ssl      The SSL context to query. | 
|  | * \return         Pointer to the SSL configuration associated with \p ssl. | 
|  | */ | 
|  | static inline const mbedtls_ssl_config *mbedtls_ssl_context_get_config( | 
|  | const mbedtls_ssl_context *ssl) | 
|  | { | 
|  | return ssl->MBEDTLS_PRIVATE(conf); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief          Set the underlying BIO callbacks for write, read and | 
|  | *                 read-with-timeout. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param p_bio    parameter (context) shared by BIO callbacks | 
|  | * \param f_send   write callback | 
|  | * \param f_recv   read callback | 
|  | * \param f_recv_timeout blocking read callback with timeout. | 
|  | * | 
|  | * \note           One of f_recv or f_recv_timeout can be NULL, in which case | 
|  | *                 the other is used. If both are non-NULL, f_recv_timeout is | 
|  | *                 used and f_recv is ignored (as if it were NULL). | 
|  | * | 
|  | * \note           The two most common use cases are: | 
|  | *                 - non-blocking I/O, f_recv != NULL, f_recv_timeout == NULL | 
|  | *                 - blocking I/O, f_recv == NULL, f_recv_timeout != NULL | 
|  | * | 
|  | * \note           For DTLS, you need to provide either a non-NULL | 
|  | *                 f_recv_timeout callback, or a f_recv that doesn't block. | 
|  | * | 
|  | * \note           See the documentations of \c mbedtls_ssl_send_t, | 
|  | *                 \c mbedtls_ssl_recv_t and \c mbedtls_ssl_recv_timeout_t for | 
|  | *                 the conventions those callbacks must follow. | 
|  | * | 
|  | * \note           On some platforms, net_sockets.c provides | 
|  | *                 \c mbedtls_net_send(), \c mbedtls_net_recv() and | 
|  | *                 \c mbedtls_net_recv_timeout() that are suitable to be used | 
|  | *                 here. | 
|  | */ | 
|  | void mbedtls_ssl_set_bio(mbedtls_ssl_context *ssl, | 
|  | void *p_bio, | 
|  | mbedtls_ssl_send_t *f_send, | 
|  | mbedtls_ssl_recv_t *f_recv, | 
|  | mbedtls_ssl_recv_timeout_t *f_recv_timeout); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_DTLS) | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | 
|  |  | 
|  |  | 
|  | /** | 
|  | * \brief             Configure the use of the Connection ID (CID) | 
|  | *                    extension in the next handshake. | 
|  | * | 
|  | *                    Reference: RFC 9146 (or draft-ietf-tls-dtls-connection-id-05 | 
|  | *                    https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05 | 
|  | *                    for legacy version) | 
|  | * | 
|  | *                    The DTLS CID extension allows the reliable association of | 
|  | *                    DTLS records to DTLS connections across changes in the | 
|  | *                    underlying transport (changed IP and Port metadata) by | 
|  | *                    adding explicit connection identifiers (CIDs) to the | 
|  | *                    headers of encrypted DTLS records. The desired CIDs are | 
|  | *                    configured by the application layer and are exchanged in | 
|  | *                    new `ClientHello` / `ServerHello` extensions during the | 
|  | *                    handshake, where each side indicates the CID it wants the | 
|  | *                    peer to use when writing encrypted messages. The CIDs are | 
|  | *                    put to use once records get encrypted: the stack discards | 
|  | *                    any incoming records that don't include the configured CID | 
|  | *                    in their header, and adds the peer's requested CID to the | 
|  | *                    headers of outgoing messages. | 
|  | * | 
|  | *                    This API enables or disables the use of the CID extension | 
|  | *                    in the next handshake and sets the value of the CID to | 
|  | *                    be used for incoming messages. | 
|  | * | 
|  | * \param ssl         The SSL context to configure. This must be initialized. | 
|  | * \param enable      This value determines whether the CID extension should | 
|  | *                    be used or not. Possible values are: | 
|  | *                    - MBEDTLS_SSL_CID_ENABLED to enable the use of the CID. | 
|  | *                    - MBEDTLS_SSL_CID_DISABLED (default) to disable the use | 
|  | *                      of the CID. | 
|  | * \param own_cid     The address of the readable buffer holding the CID we want | 
|  | *                    the peer to use when sending encrypted messages to us. | 
|  | *                    This may be \c NULL if \p own_cid_len is \c 0. | 
|  | *                    This parameter is unused if \p enabled is set to | 
|  | *                    MBEDTLS_SSL_CID_DISABLED. | 
|  | * \param own_cid_len The length of \p own_cid. | 
|  | *                    This parameter is unused if \p enabled is set to | 
|  | *                    MBEDTLS_SSL_CID_DISABLED. | 
|  | * | 
|  | * \note              The value of \p own_cid_len must match the value of the | 
|  | *                    \c len parameter passed to mbedtls_ssl_conf_cid() | 
|  | *                    when configuring the ::mbedtls_ssl_config that \p ssl | 
|  | *                    is bound to. | 
|  | * | 
|  | * \note              This CID configuration applies to subsequent handshakes | 
|  | *                    performed on the SSL context \p ssl, but does not trigger | 
|  | *                    one. You still have to call `mbedtls_ssl_handshake()` | 
|  | *                    (for the initial handshake) or `mbedtls_ssl_renegotiate()` | 
|  | *                    (for a renegotiation handshake) explicitly after a | 
|  | *                    successful call to this function to run the handshake. | 
|  | * | 
|  | * \note              This call cannot guarantee that the use of the CID | 
|  | *                    will be successfully negotiated in the next handshake, | 
|  | *                    because the peer might not support it. Specifically: | 
|  | *                    - On the Client, enabling the use of the CID through | 
|  | *                      this call implies that the `ClientHello` in the next | 
|  | *                      handshake will include the CID extension, thereby | 
|  | *                      offering the use of the CID to the server. Only if | 
|  | *                      the `ServerHello` contains the CID extension, too, | 
|  | *                      the CID extension will actually be put to use. | 
|  | *                    - On the Server, enabling the use of the CID through | 
|  | *                      this call implies that the server will look for | 
|  | *                      the CID extension in a `ClientHello` from the client, | 
|  | *                      and, if present, reply with a CID extension in its | 
|  | *                      `ServerHello`. | 
|  | * | 
|  | * \note              To check whether the use of the CID was negotiated | 
|  | *                    after the subsequent handshake has completed, please | 
|  | *                    use the API mbedtls_ssl_get_peer_cid(). | 
|  | * | 
|  | * \warning           If the use of the CID extension is enabled in this call | 
|  | *                    and the subsequent handshake negotiates its use, Mbed TLS | 
|  | *                    will silently drop every packet whose CID does not match | 
|  | *                    the CID configured in \p own_cid. It is the responsibility | 
|  | *                    of the user to adapt the underlying transport to take care | 
|  | *                    of CID-based demultiplexing before handing datagrams to | 
|  | *                    Mbed TLS. | 
|  | * | 
|  | * \return            \c 0 on success. In this case, the CID configuration | 
|  | *                    applies to the next handshake. | 
|  | * \return            A negative error code on failure. | 
|  | */ | 
|  | int mbedtls_ssl_set_cid(mbedtls_ssl_context *ssl, | 
|  | int enable, | 
|  | unsigned char const *own_cid, | 
|  | size_t own_cid_len); | 
|  |  | 
|  | /** | 
|  | * \brief              Get information about our request for usage of the CID | 
|  | *                     extension in the current connection. | 
|  | * | 
|  | * \param ssl          The SSL context to query. | 
|  | * \param enabled      The address at which to store whether the CID extension | 
|  | *                     is requested to be used or not. If the CID is | 
|  | *                     requested, `*enabled` is set to | 
|  | *                     MBEDTLS_SSL_CID_ENABLED; otherwise, it is set to | 
|  | *                     MBEDTLS_SSL_CID_DISABLED. | 
|  | * \param own_cid      The address of the buffer in which to store our own | 
|  | *                     CID (if the CID extension is requested). This may be | 
|  | *                     \c NULL in case the value of our CID isn't needed. If | 
|  | *                     it is not \c NULL, \p own_cid_len must not be \c NULL. | 
|  | * \param own_cid_len  The address at which to store the size of our own CID | 
|  | *                     (if the CID extension is requested). This is also the | 
|  | *                     number of Bytes in \p own_cid that have been written. | 
|  | *                     This may be \c NULL in case the length of our own CID | 
|  | *                     isn't needed. If it is \c NULL, \p own_cid must be | 
|  | *                     \c NULL, too. | 
|  | * | 
|  | *\note                If we are requesting an empty CID this function sets | 
|  | *                     `*enabled` to #MBEDTLS_SSL_CID_DISABLED (the rationale | 
|  | *                     for this is that the resulting outcome is the | 
|  | *                     same as if the CID extensions wasn't requested). | 
|  | * | 
|  | * \return            \c 0 on success. | 
|  | * \return            A negative error code on failure. | 
|  | */ | 
|  | int mbedtls_ssl_get_own_cid(mbedtls_ssl_context *ssl, | 
|  | int *enabled, | 
|  | unsigned char own_cid[MBEDTLS_SSL_CID_OUT_LEN_MAX], | 
|  | size_t *own_cid_len); | 
|  |  | 
|  | /** | 
|  | * \brief              Get information about the use of the CID extension | 
|  | *                     in the current connection. | 
|  | * | 
|  | * \param ssl          The SSL context to query. | 
|  | * \param enabled      The address at which to store whether the CID extension | 
|  | *                     is currently in use or not. If the CID is in use, | 
|  | *                     `*enabled` is set to MBEDTLS_SSL_CID_ENABLED; | 
|  | *                     otherwise, it is set to MBEDTLS_SSL_CID_DISABLED. | 
|  | * \param peer_cid     The address of the buffer in which to store the CID | 
|  | *                     chosen by the peer (if the CID extension is used). | 
|  | *                     This may be \c NULL in case the value of peer CID | 
|  | *                     isn't needed. If it is not \c NULL, \p peer_cid_len | 
|  | *                     must not be \c NULL. | 
|  | * \param peer_cid_len The address at which to store the size of the CID | 
|  | *                     chosen by the peer (if the CID extension is used). | 
|  | *                     This is also the number of Bytes in \p peer_cid that | 
|  | *                     have been written. | 
|  | *                     This may be \c NULL in case the length of the peer CID | 
|  | *                     isn't needed. If it is \c NULL, \p peer_cid must be | 
|  | *                     \c NULL, too. | 
|  | * | 
|  | * \note               This applies to the state of the CID negotiated in | 
|  | *                     the last complete handshake. If a handshake is in | 
|  | *                     progress, this function will attempt to complete | 
|  | *                     the handshake first. | 
|  | * | 
|  | * \note               If CID extensions have been exchanged but both client | 
|  | *                     and server chose to use an empty CID, this function | 
|  | *                     sets `*enabled` to #MBEDTLS_SSL_CID_DISABLED | 
|  | *                     (the rationale for this is that the resulting | 
|  | *                     communication is the same as if the CID extensions | 
|  | *                     hadn't been used). | 
|  | * | 
|  | * \return            \c 0 on success. | 
|  | * \return            A negative error code on failure. | 
|  | */ | 
|  | int mbedtls_ssl_get_peer_cid(mbedtls_ssl_context *ssl, | 
|  | int *enabled, | 
|  | unsigned char peer_cid[MBEDTLS_SSL_CID_OUT_LEN_MAX], | 
|  | size_t *peer_cid_len); | 
|  |  | 
|  | #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set the Maximum Transport Unit (MTU). | 
|  | *                 Special value: 0 means unset (no limit). | 
|  | *                 This represents the maximum size of a datagram payload | 
|  | *                 handled by the transport layer (usually UDP) as determined | 
|  | *                 by the network link and stack. In practice, this controls | 
|  | *                 the maximum size datagram the DTLS layer will pass to the | 
|  | *                 \c f_send() callback set using \c mbedtls_ssl_set_bio(). | 
|  | * | 
|  | * \note           The limit on datagram size is converted to a limit on | 
|  | *                 record payload by subtracting the current overhead of | 
|  | *                 encapsulation and encryption/authentication if any. | 
|  | * | 
|  | * \note           This can be called at any point during the connection, for | 
|  | *                 example when a Path Maximum Transfer Unit (PMTU) | 
|  | *                 estimate becomes available from other sources, | 
|  | *                 such as lower (or higher) protocol layers. | 
|  | * | 
|  | * \note           This setting only controls the size of the packets we send, | 
|  | *                 and does not restrict the size of the datagrams we're | 
|  | *                 willing to receive. Client-side, you can request the | 
|  | *                 server to use smaller records with \c | 
|  | *                 mbedtls_ssl_conf_max_frag_len(). | 
|  | * | 
|  | * \note           If both a MTU and a maximum fragment length have been | 
|  | *                 configured (or negotiated with the peer), the resulting | 
|  | *                 lower limit on record payload (see first note) is used. | 
|  | * | 
|  | * \note           This can only be used to decrease the maximum size | 
|  | *                 of datagrams (hence records, see first note) sent. It | 
|  | *                 cannot be used to increase the maximum size of records over | 
|  | *                 the limit set by #MBEDTLS_SSL_OUT_CONTENT_LEN. | 
|  | * | 
|  | * \note           Values lower than the current record layer expansion will | 
|  | *                 result in an error when trying to send data. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param mtu      Value of the path MTU in bytes | 
|  | */ | 
|  | void mbedtls_ssl_set_mtu(mbedtls_ssl_context *ssl, uint16_t mtu); | 
|  | #endif /* MBEDTLS_SSL_PROTO_DTLS */ | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | /** | 
|  | * \brief          Set a connection-specific verification callback (optional). | 
|  | * | 
|  | *                 If set, the provided verify callback is called for each | 
|  | *                 certificate in the peer's CRT chain, including the trusted | 
|  | *                 root. For more information, please see the documentation of | 
|  | *                 \c mbedtls_x509_crt_verify(). | 
|  | * | 
|  | * \note           This call is analogous to mbedtls_ssl_conf_verify() but | 
|  | *                 binds the verification callback and context to an SSL context | 
|  | *                 as opposed to an SSL configuration. | 
|  | *                 If mbedtls_ssl_conf_verify() and mbedtls_ssl_set_verify() | 
|  | *                 are both used, mbedtls_ssl_set_verify() takes precedence. | 
|  | * | 
|  | * \param ssl      The SSL context to use. | 
|  | * \param f_vrfy   The verification callback to use during CRT verification. | 
|  | * \param p_vrfy   The opaque context to be passed to the callback. | 
|  | */ | 
|  | void mbedtls_ssl_set_verify(mbedtls_ssl_context *ssl, | 
|  | int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *), | 
|  | void *p_vrfy); | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set the timeout period for mbedtls_ssl_read() | 
|  | *                 (Default: no timeout.) | 
|  | * | 
|  | * \param conf     SSL configuration context | 
|  | * \param timeout  Timeout value in milliseconds. | 
|  | *                 Use 0 for no timeout (default). | 
|  | * | 
|  | * \note           With blocking I/O, this will only work if a non-NULL | 
|  | *                 \c f_recv_timeout was set with \c mbedtls_ssl_set_bio(). | 
|  | *                 With non-blocking I/O, this will only work if timer | 
|  | *                 callbacks were set with \c mbedtls_ssl_set_timer_cb(). | 
|  | * | 
|  | * \note           With non-blocking I/O, you may also skip this function | 
|  | *                 altogether and handle timeouts at the application layer. | 
|  | */ | 
|  | void mbedtls_ssl_conf_read_timeout(mbedtls_ssl_config *conf, uint32_t timeout); | 
|  |  | 
|  | /** | 
|  | * \brief          Check whether a buffer contains a valid and authentic record | 
|  | *                 that has not been seen before. (DTLS only). | 
|  | * | 
|  | *                 This function does not change the user-visible state | 
|  | *                 of the SSL context. Its sole purpose is to provide | 
|  | *                 an indication of the legitimacy of an incoming record. | 
|  | * | 
|  | *                 This can be useful e.g. in distributed server environments | 
|  | *                 using the DTLS Connection ID feature, in which connections | 
|  | *                 might need to be passed between service instances on a change | 
|  | *                 of peer address, but where such disruptive operations should | 
|  | *                 only happen after the validity of incoming records has been | 
|  | *                 confirmed. | 
|  | * | 
|  | * \param ssl      The SSL context to use. | 
|  | * \param buf      The address of the buffer holding the record to be checked. | 
|  | *                 This must be a read/write buffer of length \p buflen Bytes. | 
|  | * \param buflen   The length of \p buf in Bytes. | 
|  | * | 
|  | * \note           This routine only checks whether the provided buffer begins | 
|  | *                 with a valid and authentic record that has not been seen | 
|  | *                 before, but does not check potential data following the | 
|  | *                 initial record. In particular, it is possible to pass DTLS | 
|  | *                 datagrams containing multiple records, in which case only | 
|  | *                 the first record is checked. | 
|  | * | 
|  | * \note           This function modifies the input buffer \p buf. If you need | 
|  | *                 to preserve the original record, you have to maintain a copy. | 
|  | * | 
|  | * \return         \c 0 if the record is valid and authentic and has not been | 
|  | *                 seen before. | 
|  | * \return         MBEDTLS_ERR_SSL_INVALID_MAC if the check completed | 
|  | *                 successfully but the record was found to be not authentic. | 
|  | * \return         MBEDTLS_ERR_SSL_INVALID_RECORD if the check completed | 
|  | *                 successfully but the record was found to be invalid for | 
|  | *                 a reason different from authenticity checking. | 
|  | * \return         MBEDTLS_ERR_SSL_UNEXPECTED_RECORD if the check completed | 
|  | *                 successfully but the record was found to be unexpected | 
|  | *                 in the state of the SSL context, including replayed records. | 
|  | * \return         Another negative error code on different kinds of failure. | 
|  | *                 In this case, the SSL context becomes unusable and needs | 
|  | *                 to be freed or reset before reuse. | 
|  | */ | 
|  | int mbedtls_ssl_check_record(mbedtls_ssl_context const *ssl, | 
|  | unsigned char *buf, | 
|  | size_t buflen); | 
|  |  | 
|  | /** | 
|  | * \brief          Set the timer callbacks (Mandatory for DTLS.) | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param p_timer  parameter (context) shared by timer callbacks | 
|  | * \param f_set_timer   set timer callback | 
|  | * \param f_get_timer   get timer callback. Must return: | 
|  | * | 
|  | * \note           See the documentation of \c mbedtls_ssl_set_timer_t and | 
|  | *                 \c mbedtls_ssl_get_timer_t for the conventions this pair of | 
|  | *                 callbacks must follow. | 
|  | * | 
|  | * \note           On some platforms, timing.c provides | 
|  | *                 \c mbedtls_timing_set_delay() and | 
|  | *                 \c mbedtls_timing_get_delay() that are suitable for using | 
|  | *                 here, except if using an event-driven style. | 
|  | * | 
|  | * \note           See also the "DTLS tutorial" article in our knowledge base. | 
|  | *                 https://mbed-tls.readthedocs.io/en/latest/kb/how-to/dtls-tutorial | 
|  | */ | 
|  | void mbedtls_ssl_set_timer_cb(mbedtls_ssl_context *ssl, | 
|  | void *p_timer, | 
|  | mbedtls_ssl_set_timer_t *f_set_timer, | 
|  | mbedtls_ssl_get_timer_t *f_get_timer); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief           Set the certificate selection callback (server-side only). | 
|  | * | 
|  | *                  If set, the callback is always called for each handshake, | 
|  | *                  after `ClientHello` processing has finished. | 
|  | * | 
|  | * \param conf      The SSL configuration to register the callback with. | 
|  | * \param f_cert_cb The callback for selecting server certificate after | 
|  | *                  `ClientHello` processing has finished. | 
|  | */ | 
|  | static inline void mbedtls_ssl_conf_cert_cb(mbedtls_ssl_config *conf, | 
|  | mbedtls_ssl_hs_cb_t f_cert_cb) | 
|  | { | 
|  | conf->MBEDTLS_PRIVATE(f_cert_cb) = f_cert_cb; | 
|  | } | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | /** | 
|  | * \brief           Callback type: generate and write session ticket | 
|  | * | 
|  | * \note            This describes what a callback implementation should do. | 
|  | *                  This callback should generate an encrypted and | 
|  | *                  authenticated ticket for the session and write it to the | 
|  | *                  output buffer. Here, ticket means the opaque ticket part | 
|  | *                  of the NewSessionTicket structure of RFC 5077. | 
|  | * | 
|  | * \param p_ticket  Context for the callback | 
|  | * \param session   SSL session to be written in the ticket | 
|  | * \param start     Start of the output buffer | 
|  | * \param end       End of the output buffer | 
|  | * \param tlen      On exit, holds the length written | 
|  | * \param lifetime  On exit, holds the lifetime of the ticket in seconds | 
|  | * | 
|  | * \return          0 if successful, or | 
|  | *                  a specific MBEDTLS_ERR_XXX code. | 
|  | */ | 
|  | typedef int mbedtls_ssl_ticket_write_t(void *p_ticket, | 
|  | const mbedtls_ssl_session *session, | 
|  | unsigned char *start, | 
|  | const unsigned char *end, | 
|  | size_t *tlen, | 
|  | uint32_t *lifetime); | 
|  |  | 
|  | /** | 
|  | * \brief           Callback type: parse and load session ticket | 
|  | * | 
|  | * \note            This describes what a callback implementation should do. | 
|  | *                  This callback should parse a session ticket as generated | 
|  | *                  by the corresponding mbedtls_ssl_ticket_write_t function, | 
|  | *                  and, if the ticket is authentic and valid, load the | 
|  | *                  session. | 
|  | * | 
|  | * \note            The implementation is allowed to modify the first len | 
|  | *                  bytes of the input buffer, eg to use it as a temporary | 
|  | *                  area for the decrypted ticket contents. | 
|  | * | 
|  | * \param p_ticket  Context for the callback | 
|  | * \param session   SSL session to be loaded | 
|  | * \param buf       Start of the buffer containing the ticket | 
|  | * \param len       Length of the ticket. | 
|  | * | 
|  | * \return          0 if successful, or | 
|  | *                  MBEDTLS_ERR_SSL_INVALID_MAC if not authentic, or | 
|  | *                  MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED if expired, or | 
|  | *                  any other non-zero code for other failures. | 
|  | */ | 
|  | typedef int mbedtls_ssl_ticket_parse_t(void *p_ticket, | 
|  | mbedtls_ssl_session *session, | 
|  | unsigned char *buf, | 
|  | size_t len); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief           Configure SSL session ticket callbacks (server only). | 
|  | *                  (Default: none.) | 
|  | * | 
|  | * \note            On server, session tickets are enabled by providing | 
|  | *                  non-NULL callbacks. | 
|  | * | 
|  | * \note            On client, use \c mbedtls_ssl_conf_session_tickets(). | 
|  | * | 
|  | * \param conf      SSL configuration context | 
|  | * \param f_ticket_write    Callback for writing a ticket | 
|  | * \param f_ticket_parse    Callback for parsing a ticket | 
|  | * \param p_ticket          Context shared by the two callbacks | 
|  | */ | 
|  | void mbedtls_ssl_conf_session_tickets_cb(mbedtls_ssl_config *conf, | 
|  | mbedtls_ssl_ticket_write_t *f_ticket_write, | 
|  | mbedtls_ssl_ticket_parse_t *f_ticket_parse, | 
|  | void *p_ticket); | 
|  | #endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | /** | 
|  | * \brief   Configure a key export callback. | 
|  | *          (Default: none.) | 
|  | * | 
|  | *          This API can be used for two purposes: | 
|  | *          - Debugging: Use this API to e.g. generate an NSSKeylog | 
|  | *            file and use it to inspect encrypted traffic in tools | 
|  | *            such as Wireshark. | 
|  | *          - Application-specific export: Use this API to implement | 
|  | *            key exporters, e.g. for EAP-TLS or DTLS-SRTP. | 
|  | * | 
|  | * | 
|  | * \param ssl            The SSL context to which the export | 
|  | *                       callback should be attached. | 
|  | * \param f_export_keys  The callback for the key export. | 
|  | * \param p_export_keys  The opaque context pointer to be passed to the | 
|  | *                       callback \p f_export_keys. | 
|  | */ | 
|  | void mbedtls_ssl_set_export_keys_cb(mbedtls_ssl_context *ssl, | 
|  | mbedtls_ssl_export_keys_t *f_export_keys, | 
|  | void *p_export_keys); | 
|  |  | 
|  | /** \brief Set the user data in an SSL configuration to a pointer. | 
|  | * | 
|  | * You can retrieve this value later with mbedtls_ssl_conf_get_user_data_p(). | 
|  | * | 
|  | * \note The library stores \c p without accessing it. It is the responsibility | 
|  | *       of the caller to ensure that the pointer remains valid. | 
|  | * | 
|  | * \param conf           The SSL configuration context to modify. | 
|  | * \param p              The new value of the user data. | 
|  | */ | 
|  | static inline void mbedtls_ssl_conf_set_user_data_p( | 
|  | mbedtls_ssl_config *conf, | 
|  | void *p) | 
|  | { | 
|  | conf->MBEDTLS_PRIVATE(user_data).p = p; | 
|  | } | 
|  |  | 
|  | /** \brief Set the user data in an SSL configuration to an integer. | 
|  | * | 
|  | * You can retrieve this value later with mbedtls_ssl_conf_get_user_data_n(). | 
|  | * | 
|  | * \param conf           The SSL configuration context to modify. | 
|  | * \param n              The new value of the user data. | 
|  | */ | 
|  | static inline void mbedtls_ssl_conf_set_user_data_n( | 
|  | mbedtls_ssl_config *conf, | 
|  | uintptr_t n) | 
|  | { | 
|  | conf->MBEDTLS_PRIVATE(user_data).n = n; | 
|  | } | 
|  |  | 
|  | /** \brief Retrieve the user data in an SSL configuration as a pointer. | 
|  | * | 
|  | * This is the value last set with mbedtls_ssl_conf_set_user_data_p(), or | 
|  | * \c NULL if mbedtls_ssl_conf_set_user_data_p() has not previously been | 
|  | * called. The value is undefined if mbedtls_ssl_conf_set_user_data_n() has | 
|  | * been called without a subsequent call to mbedtls_ssl_conf_set_user_data_p(). | 
|  | * | 
|  | * \param conf           The SSL configuration context to modify. | 
|  | * \return               The current value of the user data. | 
|  | */ | 
|  | static inline void *mbedtls_ssl_conf_get_user_data_p( | 
|  | mbedtls_ssl_config *conf) | 
|  | { | 
|  | return conf->MBEDTLS_PRIVATE(user_data).p; | 
|  | } | 
|  |  | 
|  | /** \brief Retrieve the user data in an SSL configuration as an integer. | 
|  | * | 
|  | * This is the value last set with mbedtls_ssl_conf_set_user_data_n(), or | 
|  | * \c 0 if mbedtls_ssl_conf_set_user_data_n() has not previously been | 
|  | * called. The value is undefined if mbedtls_ssl_conf_set_user_data_p() has | 
|  | * been called without a subsequent call to mbedtls_ssl_conf_set_user_data_n(). | 
|  | * | 
|  | * \param conf           The SSL configuration context to modify. | 
|  | * \return               The current value of the user data. | 
|  | */ | 
|  | static inline uintptr_t mbedtls_ssl_conf_get_user_data_n( | 
|  | mbedtls_ssl_config *conf) | 
|  | { | 
|  | return conf->MBEDTLS_PRIVATE(user_data).n; | 
|  | } | 
|  |  | 
|  | /** \brief Set the user data in an SSL context to a pointer. | 
|  | * | 
|  | * You can retrieve this value later with mbedtls_ssl_get_user_data_p(). | 
|  | * | 
|  | * \note The library stores \c p without accessing it. It is the responsibility | 
|  | *       of the caller to ensure that the pointer remains valid. | 
|  | * | 
|  | * \param ssl            The SSL context to modify. | 
|  | * \param p              The new value of the user data. | 
|  | */ | 
|  | static inline void mbedtls_ssl_set_user_data_p( | 
|  | mbedtls_ssl_context *ssl, | 
|  | void *p) | 
|  | { | 
|  | ssl->MBEDTLS_PRIVATE(user_data).p = p; | 
|  | } | 
|  |  | 
|  | /** \brief Set the user data in an SSL context to an integer. | 
|  | * | 
|  | * You can retrieve this value later with mbedtls_ssl_get_user_data_n(). | 
|  | * | 
|  | * \param ssl            The SSL context to modify. | 
|  | * \param n              The new value of the user data. | 
|  | */ | 
|  | static inline void mbedtls_ssl_set_user_data_n( | 
|  | mbedtls_ssl_context *ssl, | 
|  | uintptr_t n) | 
|  | { | 
|  | ssl->MBEDTLS_PRIVATE(user_data).n = n; | 
|  | } | 
|  |  | 
|  | /** \brief Retrieve the user data in an SSL context as a pointer. | 
|  | * | 
|  | * This is the value last set with mbedtls_ssl_set_user_data_p(), or | 
|  | * \c NULL if mbedtls_ssl_set_user_data_p() has not previously been | 
|  | * called. The value is undefined if mbedtls_ssl_set_user_data_n() has | 
|  | * been called without a subsequent call to mbedtls_ssl_set_user_data_p(). | 
|  | * | 
|  | * \param ssl            The SSL context to modify. | 
|  | * \return               The current value of the user data. | 
|  | */ | 
|  | static inline void *mbedtls_ssl_get_user_data_p( | 
|  | mbedtls_ssl_context *ssl) | 
|  | { | 
|  | return ssl->MBEDTLS_PRIVATE(user_data).p; | 
|  | } | 
|  |  | 
|  | /** \brief Retrieve the user data in an SSL context as an integer. | 
|  | * | 
|  | * This is the value last set with mbedtls_ssl_set_user_data_n(), or | 
|  | * \c 0 if mbedtls_ssl_set_user_data_n() has not previously been | 
|  | * called. The value is undefined if mbedtls_ssl_set_user_data_p() has | 
|  | * been called without a subsequent call to mbedtls_ssl_set_user_data_n(). | 
|  | * | 
|  | * \param ssl            The SSL context to modify. | 
|  | * \return               The current value of the user data. | 
|  | */ | 
|  | static inline uintptr_t mbedtls_ssl_get_user_data_n( | 
|  | mbedtls_ssl_context *ssl) | 
|  | { | 
|  | return ssl->MBEDTLS_PRIVATE(user_data).n; | 
|  | } | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_ASYNC_PRIVATE) | 
|  | /** | 
|  | * \brief           Configure asynchronous private key operation callbacks. | 
|  | * | 
|  | * \param conf              SSL configuration context | 
|  | * \param f_async_sign      Callback to start a signature operation. See | 
|  | *                          the description of ::mbedtls_ssl_async_sign_t | 
|  | *                          for more information. This may be \c NULL if the | 
|  | *                          external processor does not support any signature | 
|  | *                          operation; in this case the private key object | 
|  | *                          associated with the certificate will be used. | 
|  | * \param f_async_decrypt   Callback to start a decryption operation. See | 
|  | *                          the description of ::mbedtls_ssl_async_decrypt_t | 
|  | *                          for more information. This may be \c NULL if the | 
|  | *                          external processor does not support any decryption | 
|  | *                          operation; in this case the private key object | 
|  | *                          associated with the certificate will be used. | 
|  | * \param f_async_resume    Callback to resume an asynchronous operation. See | 
|  | *                          the description of ::mbedtls_ssl_async_resume_t | 
|  | *                          for more information. This may not be \c NULL unless | 
|  | *                          \p f_async_sign and \p f_async_decrypt are both | 
|  | *                          \c NULL. | 
|  | * \param f_async_cancel    Callback to cancel an asynchronous operation. See | 
|  | *                          the description of ::mbedtls_ssl_async_cancel_t | 
|  | *                          for more information. This may be \c NULL if | 
|  | *                          no cleanup is needed. | 
|  | * \param config_data       A pointer to configuration data which can be | 
|  | *                          retrieved with | 
|  | *                          mbedtls_ssl_conf_get_async_config_data(). The | 
|  | *                          library stores this value without dereferencing it. | 
|  | */ | 
|  | void mbedtls_ssl_conf_async_private_cb(mbedtls_ssl_config *conf, | 
|  | mbedtls_ssl_async_sign_t *f_async_sign, | 
|  | mbedtls_ssl_async_decrypt_t *f_async_decrypt, | 
|  | mbedtls_ssl_async_resume_t *f_async_resume, | 
|  | mbedtls_ssl_async_cancel_t *f_async_cancel, | 
|  | void *config_data); | 
|  |  | 
|  | /** | 
|  | * \brief           Retrieve the configuration data set by | 
|  | *                  mbedtls_ssl_conf_async_private_cb(). | 
|  | * | 
|  | * \param conf      SSL configuration context | 
|  | * \return          The configuration data set by | 
|  | *                  mbedtls_ssl_conf_async_private_cb(). | 
|  | */ | 
|  | void *mbedtls_ssl_conf_get_async_config_data(const mbedtls_ssl_config *conf); | 
|  |  | 
|  | /** | 
|  | * \brief           Retrieve the asynchronous operation user context. | 
|  | * | 
|  | * \note            This function may only be called while a handshake | 
|  | *                  is in progress. | 
|  | * | 
|  | * \param ssl       The SSL context to access. | 
|  | * | 
|  | * \return          The asynchronous operation user context that was last | 
|  | *                  set during the current handshake. If | 
|  | *                  mbedtls_ssl_set_async_operation_data() has not yet been | 
|  | *                  called during the current handshake, this function returns | 
|  | *                  \c NULL. | 
|  | */ | 
|  | void *mbedtls_ssl_get_async_operation_data(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief           Retrieve the asynchronous operation user context. | 
|  | * | 
|  | * \note            This function may only be called while a handshake | 
|  | *                  is in progress. | 
|  | * | 
|  | * \param ssl       The SSL context to access. | 
|  | * \param ctx       The new value of the asynchronous operation user context. | 
|  | *                  Call mbedtls_ssl_get_async_operation_data() later during the | 
|  | *                  same handshake to retrieve this value. | 
|  | */ | 
|  | void mbedtls_ssl_set_async_operation_data(mbedtls_ssl_context *ssl, | 
|  | void *ctx); | 
|  | #endif /* MBEDTLS_SSL_ASYNC_PRIVATE */ | 
|  |  | 
|  | /** | 
|  | * \brief          Callback type: generate a cookie | 
|  | * | 
|  | * \param ctx      Context for the callback | 
|  | * \param p        Buffer to write to, | 
|  | *                 must be updated to point right after the cookie | 
|  | * \param end      Pointer to one past the end of the output buffer | 
|  | * \param info     Client ID info that was passed to | 
|  | *                 \c mbedtls_ssl_set_client_transport_id() | 
|  | * \param ilen     Length of info in bytes | 
|  | * | 
|  | * \return         The callback must return 0 on success, | 
|  | *                 or a negative error code. | 
|  | */ | 
|  | typedef int mbedtls_ssl_cookie_write_t(void *ctx, | 
|  | unsigned char **p, unsigned char *end, | 
|  | const unsigned char *info, size_t ilen); | 
|  |  | 
|  | /** | 
|  | * \brief          Callback type: verify a cookie | 
|  | * | 
|  | * \param ctx      Context for the callback | 
|  | * \param cookie   Cookie to verify | 
|  | * \param clen     Length of cookie | 
|  | * \param info     Client ID info that was passed to | 
|  | *                 \c mbedtls_ssl_set_client_transport_id() | 
|  | * \param ilen     Length of info in bytes | 
|  | * | 
|  | * \return         The callback must return 0 if cookie is valid, | 
|  | *                 or a negative error code. | 
|  | */ | 
|  | typedef int mbedtls_ssl_cookie_check_t(void *ctx, | 
|  | const unsigned char *cookie, size_t clen, | 
|  | const unsigned char *info, size_t ilen); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief           Register callbacks for DTLS cookies | 
|  | *                  (Server only. DTLS only.) | 
|  | * | 
|  | *                  Default: dummy callbacks that fail, in order to force you to | 
|  | *                  register working callbacks (and initialize their context). | 
|  | * | 
|  | *                  To disable HelloVerifyRequest, register NULL callbacks. | 
|  | * | 
|  | * \warning         Disabling hello verification allows your server to be used | 
|  | *                  for amplification in DoS attacks against other hosts. | 
|  | *                  Only disable if you known this can't happen in your | 
|  | *                  particular environment. | 
|  | * | 
|  | * \note            See comments on \c mbedtls_ssl_handshake() about handling | 
|  | *                  the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected | 
|  | *                  on the first handshake attempt when this is enabled. | 
|  | * | 
|  | * \note            This is also necessary to handle client reconnection from | 
|  | *                  the same port as described in RFC 6347 section 4.2.8 (only | 
|  | *                  the variant with cookies is supported currently). See | 
|  | *                  comments on \c mbedtls_ssl_read() for details. | 
|  | * | 
|  | * \param conf              SSL configuration | 
|  | * \param f_cookie_write    Cookie write callback | 
|  | * \param f_cookie_check    Cookie check callback | 
|  | * \param p_cookie          Context for both callbacks | 
|  | */ | 
|  | void mbedtls_ssl_conf_dtls_cookies(mbedtls_ssl_config *conf, | 
|  | mbedtls_ssl_cookie_write_t *f_cookie_write, | 
|  | mbedtls_ssl_cookie_check_t *f_cookie_check, | 
|  | void *p_cookie); | 
|  |  | 
|  | /** | 
|  | * \brief          Set client's transport-level identification info. | 
|  | *                 (Server only. DTLS only.) | 
|  | * | 
|  | *                 This is usually the IP address (and port), but could be | 
|  | *                 anything identify the client depending on the underlying | 
|  | *                 network stack. Used for HelloVerifyRequest with DTLS. | 
|  | *                 This is *not* used to route the actual packets. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param info     Transport-level info identifying the client (eg IP + port) | 
|  | * \param ilen     Length of info in bytes | 
|  | * | 
|  | * \note           An internal copy is made, so the info buffer can be reused. | 
|  | * | 
|  | * \return         0 on success, | 
|  | *                 MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client, | 
|  | *                 MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory. | 
|  | */ | 
|  | int mbedtls_ssl_set_client_transport_id(mbedtls_ssl_context *ssl, | 
|  | const unsigned char *info, | 
|  | size_t ilen); | 
|  |  | 
|  | #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY) | 
|  | /** | 
|  | * \brief          Enable or disable anti-replay protection for DTLS. | 
|  | *                 (DTLS only, no effect on TLS.) | 
|  | *                 Default: enabled. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param mode     MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED. | 
|  | * | 
|  | * \warning        Disabling this is a security risk unless the application | 
|  | *                 protocol handles duplicated packets in a safe way. You | 
|  | *                 should not disable this without careful consideration. | 
|  | *                 However, if your application already detects duplicated | 
|  | *                 packets and needs information about them to adjust its | 
|  | *                 transmission strategy, then you'll want to disable this. | 
|  | */ | 
|  | void mbedtls_ssl_conf_dtls_anti_replay(mbedtls_ssl_config *conf, char mode); | 
|  | #endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set a limit on the number of records with a bad MAC | 
|  | *                 before terminating the connection. | 
|  | *                 (DTLS only, no effect on TLS.) | 
|  | *                 Default: 0 (disabled). | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param limit    Limit, or 0 to disable. | 
|  | * | 
|  | * \note           If the limit is N, then the connection is terminated when | 
|  | *                 the Nth non-authentic record is seen. | 
|  | * | 
|  | * \note           Records with an invalid header are not counted, only the | 
|  | *                 ones going through the authentication-decryption phase. | 
|  | * | 
|  | * \note           This is a security trade-off related to the fact that it's | 
|  | *                 often relatively easy for an active attacker to inject UDP | 
|  | *                 datagrams. On one hand, setting a low limit here makes it | 
|  | *                 easier for such an attacker to forcibly terminated a | 
|  | *                 connection. On the other hand, a high limit or no limit | 
|  | *                 might make us waste resources checking authentication on | 
|  | *                 many bogus packets. | 
|  | */ | 
|  | void mbedtls_ssl_conf_dtls_badmac_limit(mbedtls_ssl_config *conf, unsigned limit); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_DTLS) | 
|  |  | 
|  | /** | 
|  | * \brief          Allow or disallow packing of multiple handshake records | 
|  | *                 within a single datagram. | 
|  | * | 
|  | * \param ssl           The SSL context to configure. | 
|  | * \param allow_packing This determines whether datagram packing may | 
|  | *                      be used or not. A value of \c 0 means that every | 
|  | *                      record will be sent in a separate datagram; a | 
|  | *                      value of \c 1 means that, if space permits, | 
|  | *                      multiple handshake messages (including CCS) belonging to | 
|  | *                      a single flight may be packed within a single datagram. | 
|  | * | 
|  | * \note           This is enabled by default and should only be disabled | 
|  | *                 for test purposes, or if datagram packing causes | 
|  | *                 interoperability issues with peers that don't support it. | 
|  | * | 
|  | * \note           Allowing datagram packing reduces the network load since | 
|  | *                 there's less overhead if multiple messages share the same | 
|  | *                 datagram. Also, it increases the handshake efficiency | 
|  | *                 since messages belonging to a single datagram will not | 
|  | *                 be reordered in transit, and so future message buffering | 
|  | *                 or flight retransmission (if no buffering is used) as | 
|  | *                 means to deal with reordering are needed less frequently. | 
|  | * | 
|  | * \note           Application records are not affected by this option and | 
|  | *                 are currently always sent in separate datagrams. | 
|  | * | 
|  | */ | 
|  | void mbedtls_ssl_set_datagram_packing(mbedtls_ssl_context *ssl, | 
|  | unsigned allow_packing); | 
|  |  | 
|  | /** | 
|  | * \brief          Set retransmit timeout values for the DTLS handshake. | 
|  | *                 (DTLS only, no effect on TLS.) | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param min      Initial timeout value in milliseconds. | 
|  | *                 Default: 1000 (1 second). | 
|  | * \param max      Maximum timeout value in milliseconds. | 
|  | *                 Default: 60000 (60 seconds). | 
|  | * | 
|  | * \note           Default values are from RFC 6347 section 4.2.4.1. | 
|  | * | 
|  | * \note           The 'min' value should typically be slightly above the | 
|  | *                 expected round-trip time to your peer, plus whatever time | 
|  | *                 it takes for the peer to process the message. For example, | 
|  | *                 if your RTT is about 600ms and you peer needs up to 1s to | 
|  | *                 do the cryptographic operations in the handshake, then you | 
|  | *                 should set 'min' slightly above 1600. Lower values of 'min' | 
|  | *                 might cause spurious resends which waste network resources, | 
|  | *                 while larger value of 'min' will increase overall latency | 
|  | *                 on unreliable network links. | 
|  | * | 
|  | * \note           The more unreliable your network connection is, the larger | 
|  | *                 your max / min ratio needs to be in order to achieve | 
|  | *                 reliable handshakes. | 
|  | * | 
|  | * \note           Messages are retransmitted up to log2(ceil(max/min)) times. | 
|  | *                 For example, if min = 1s and max = 5s, the retransmit plan | 
|  | *                 goes: send ... 1s -> resend ... 2s -> resend ... 4s -> | 
|  | *                 resend ... 5s -> give up and return a timeout error. | 
|  | */ | 
|  | void mbedtls_ssl_conf_handshake_timeout(mbedtls_ssl_config *conf, uint32_t min, uint32_t max); | 
|  | #endif /* MBEDTLS_SSL_PROTO_DTLS */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief          Set the session cache callbacks (server-side only) | 
|  | *                 If not set, no session resuming is done (except if session | 
|  | *                 tickets are enabled too). | 
|  | * | 
|  | *                 The session cache has the responsibility to check for stale | 
|  | *                 entries based on timeout. See RFC 5246 for recommendations. | 
|  | * | 
|  | *                 Warning: session.peer_cert is cleared by the SSL/TLS layer on | 
|  | *                 connection shutdown, so do not cache the pointer! Either set | 
|  | *                 it to NULL or make a full copy of the certificate. | 
|  | * | 
|  | *                 The get callback is called once during the initial handshake | 
|  | *                 to enable session resuming. The get function has the | 
|  | *                 following parameters: (void *parameter, mbedtls_ssl_session *session) | 
|  | *                 If a valid entry is found, it should fill the master of | 
|  | *                 the session object with the cached values and return 0, | 
|  | *                 return 1 otherwise. Optionally peer_cert can be set as well | 
|  | *                 if it is properly present in cache entry. | 
|  | * | 
|  | *                 The set callback is called once during the initial handshake | 
|  | *                 to enable session resuming after the entire handshake has | 
|  | *                 been finished. The set function has the following parameters: | 
|  | *                 (void *parameter, const mbedtls_ssl_session *session). The function | 
|  | *                 should create a cache entry for future retrieval based on | 
|  | *                 the data in the session structure and should keep in mind | 
|  | *                 that the mbedtls_ssl_session object presented (and all its referenced | 
|  | *                 data) is cleared by the SSL/TLS layer when the connection is | 
|  | *                 terminated. It is recommended to add metadata to determine if | 
|  | *                 an entry is still valid in the future. Return 0 if | 
|  | *                 successfully cached, return 1 otherwise. | 
|  | * | 
|  | * \param conf           SSL configuration | 
|  | * \param p_cache        parameter (context) for both callbacks | 
|  | * \param f_get_cache    session get callback | 
|  | * \param f_set_cache    session set callback | 
|  | */ | 
|  | void mbedtls_ssl_conf_session_cache(mbedtls_ssl_config *conf, | 
|  | void *p_cache, | 
|  | mbedtls_ssl_cache_get_t *f_get_cache, | 
|  | mbedtls_ssl_cache_set_t *f_set_cache); | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_CLI_C) | 
|  | /** | 
|  | * \brief          Load a session for session resumption. | 
|  | * | 
|  | *                 Sessions loaded through this call will be considered | 
|  | *                 for session resumption in the next handshake. | 
|  | * | 
|  | * \note           Even if this call succeeds, it is not guaranteed that | 
|  | *                 the next handshake will indeed be shortened through the | 
|  | *                 use of session resumption: The server is always free | 
|  | *                 to reject any attempt for resumption and fall back to | 
|  | *                 a full handshake. | 
|  | * | 
|  | * \note           This function can handle a variety of mechanisms for session | 
|  | *                 resumption: For TLS 1.2, both session ID-based resumption and | 
|  | *                 ticket-based resumption will be considered. For TLS 1.3, | 
|  | *                 once implemented, sessions equate to tickets, and loading | 
|  | *                 one or more sessions via this call will lead to their | 
|  | *                 corresponding tickets being advertised as resumption PSKs | 
|  | *                 by the client. | 
|  | * | 
|  | * \note           Calling this function multiple times will only be useful | 
|  | *                 once TLS 1.3 is supported. For TLS 1.2 connections, this | 
|  | *                 function should be called at most once. | 
|  | * | 
|  | * \param ssl      The SSL context representing the connection which should | 
|  | *                 be attempted to be setup using session resumption. This | 
|  | *                 must be initialized via mbedtls_ssl_init() and bound to | 
|  | *                 an SSL configuration via mbedtls_ssl_setup(), but | 
|  | *                 the handshake must not yet have been started. | 
|  | * \param session  The session to be considered for session resumption. | 
|  | *                 This must be a session previously exported via | 
|  | *                 mbedtls_ssl_get_session(), and potentially serialized and | 
|  | *                 deserialized through mbedtls_ssl_session_save() and | 
|  | *                 mbedtls_ssl_session_load() in the meantime. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         \c MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if the session | 
|  | *                 could not be loaded because of an implementation limitation. | 
|  | *                 This error is non-fatal, and has no observable effect on | 
|  | *                 the SSL context or the session that was attempted to be loaded. | 
|  | * \return         Another negative error code on other kinds of failure. | 
|  | * | 
|  | * \sa             mbedtls_ssl_get_session() | 
|  | * \sa             mbedtls_ssl_session_load() | 
|  | */ | 
|  | int mbedtls_ssl_set_session(mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session); | 
|  | #endif /* MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | /** | 
|  | * \brief          Load serialized session data into a session structure. | 
|  | *                 On client, this can be used for loading saved sessions | 
|  | *                 before resuming them with mbedtls_ssl_set_session(). | 
|  | *                 On server, this can be used for alternative implementations | 
|  | *                 of session cache or session tickets. | 
|  | * | 
|  | * \warning        If a peer certificate chain is associated with the session, | 
|  | *                 the serialized state will only contain the peer's | 
|  | *                 end-entity certificate and the result of the chain | 
|  | *                 verification (unless verification was disabled), but not | 
|  | *                 the rest of the chain. | 
|  | * | 
|  | * \see            mbedtls_ssl_session_save() | 
|  | * \see            mbedtls_ssl_set_session() | 
|  | * | 
|  | * \param session  The session structure to be populated. It must have been | 
|  | *                 initialised with mbedtls_ssl_session_init() but not | 
|  | *                 populated yet. | 
|  | * \param buf      The buffer holding the serialized session data. It must be a | 
|  | *                 readable buffer of at least \p len bytes. | 
|  | * \param len      The size of the serialized data in bytes. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed. | 
|  | * \return         #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid. | 
|  | * \return         #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data | 
|  | *                 was generated in a different version or configuration of | 
|  | *                 Mbed TLS. | 
|  | * \return         Another negative value for other kinds of errors (for | 
|  | *                 example, unsupported features in the embedded certificate). | 
|  | */ | 
|  | int mbedtls_ssl_session_load(mbedtls_ssl_session *session, | 
|  | const unsigned char *buf, | 
|  | size_t len); | 
|  |  | 
|  | /** | 
|  | * \brief          Save session structure as serialized data in a buffer. | 
|  | *                 On client, this can be used for saving session data, | 
|  | *                 potentially in non-volatile storage, for resuming later. | 
|  | *                 On server, this can be used for alternative implementations | 
|  | *                 of session cache or session tickets. | 
|  | * | 
|  | * \see            mbedtls_ssl_session_load() | 
|  | * | 
|  | * \param session  The session structure to be saved. | 
|  | * \param buf      The buffer to write the serialized data to. It must be a | 
|  | *                 writeable buffer of at least \p len bytes, or may be \c | 
|  | *                 NULL if \p len is \c 0. | 
|  | * \param buf_len  The number of bytes available for writing in \p buf. | 
|  | * \param olen     The size in bytes of the data that has been or would have | 
|  | *                 been written. It must point to a valid \c size_t. | 
|  | * | 
|  | * \note           \p olen is updated to the correct value regardless of | 
|  | *                 whether \p buf_len was large enough. This makes it possible | 
|  | *                 to determine the necessary size by calling this function | 
|  | *                 with \p buf set to \c NULL and \p buf_len to \c 0. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small. | 
|  | */ | 
|  | int mbedtls_ssl_session_save(const mbedtls_ssl_session *session, | 
|  | unsigned char *buf, | 
|  | size_t buf_len, | 
|  | size_t *olen); | 
|  |  | 
|  | /** | 
|  | * \brief               Set the list of allowed ciphersuites and the preference | 
|  | *                      order. First in the list has the highest preference. | 
|  | * | 
|  | *                      For TLS 1.2, the notion of ciphersuite determines both | 
|  | *                      the key exchange mechanism and the suite of symmetric | 
|  | *                      algorithms to be used during and after the handshake. | 
|  | * | 
|  | *                      For TLS 1.3 (in development), the notion of ciphersuite | 
|  | *                      only determines the suite of symmetric algorithms to be | 
|  | *                      used during and after the handshake, while key exchange | 
|  | *                      mechanisms are configured separately. | 
|  | * | 
|  | *                      In Mbed TLS, ciphersuites for both TLS 1.2 and TLS 1.3 | 
|  | *                      are configured via this function. For users of TLS 1.3, | 
|  | *                      there will be separate API for the configuration of key | 
|  | *                      exchange mechanisms. | 
|  | * | 
|  | *                      The list of ciphersuites passed to this function may | 
|  | *                      contain a mixture of TLS 1.2 and TLS 1.3 ciphersuite | 
|  | *                      identifiers. This is useful if negotiation of TLS 1.3 | 
|  | *                      should be attempted, but a fallback to TLS 1.2 would | 
|  | *                      be tolerated. | 
|  | * | 
|  | * \note                By default, the server chooses its preferred | 
|  | *                      ciphersuite among those that the client supports. If | 
|  | *                      mbedtls_ssl_conf_preference_order() is called to prefer | 
|  | *                      the client's preferences, the server instead chooses | 
|  | *                      the client's preferred ciphersuite among those that | 
|  | *                      the server supports. | 
|  | * | 
|  | * \warning             The ciphersuites array \p ciphersuites is not copied. | 
|  | *                      It must remain valid for the lifetime of the SSL | 
|  | *                      configuration \p conf. | 
|  | * | 
|  | * \param conf          The SSL configuration to modify. | 
|  | * \param ciphersuites  A 0-terminated list of IANA identifiers of supported | 
|  | *                      ciphersuites, accessible through \c MBEDTLS_TLS_XXX | 
|  | *                      and \c MBEDTLS_TLS1_3_XXX macros defined in | 
|  | *                      ssl_ciphersuites.h. | 
|  | */ | 
|  | void mbedtls_ssl_conf_ciphersuites(mbedtls_ssl_config *conf, | 
|  | const int *ciphersuites); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_PROTO_TLS1_3) | 
|  | /** | 
|  | * \brief Set the supported key exchange modes for TLS 1.3 connections. | 
|  | * | 
|  | *        In contrast to TLS 1.2, the ciphersuite concept in TLS 1.3 does not | 
|  | *        include the choice of key exchange mechanism. It is therefore not | 
|  | *        covered by the API mbedtls_ssl_conf_ciphersuites(). See the | 
|  | *        documentation of mbedtls_ssl_conf_ciphersuites() for more | 
|  | *        information on the ciphersuite concept in TLS 1.2 and TLS 1.3. | 
|  | * | 
|  | *        The present function is specific to TLS 1.3 and allows users to | 
|  | *        configure the set of supported key exchange mechanisms in TLS 1.3. | 
|  | * | 
|  | * \param conf       The SSL configuration the change should apply to. | 
|  | * \param kex_modes  A bitwise combination of one or more of the following: | 
|  | *                   - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK | 
|  | *                     This flag enables pure-PSK key exchanges. | 
|  | *                   - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL | 
|  | *                     This flag enables combined PSK-ephemeral key exchanges. | 
|  | *                   - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL | 
|  | *                     This flag enables pure-ephemeral key exchanges. | 
|  | *                   For convenience, the following pre-defined macros are | 
|  | *                   available for combinations of the above: | 
|  | *                   - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_ALL | 
|  | *                     Includes all of pure-PSK, PSK-ephemeral and pure-ephemeral. | 
|  | *                   - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL | 
|  | *                     Includes both pure-PSK and combined PSK-ephemeral | 
|  | *                     key exchanges, but excludes pure-ephemeral key exchanges. | 
|  | *                   - MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ALL | 
|  | *                     Includes both pure-ephemeral and combined PSK-ephemeral | 
|  | *                     key exchanges. | 
|  | * | 
|  | * \note  If a PSK-based key exchange mode shall be supported, applications | 
|  | *        must also use the APIs mbedtls_ssl_conf_psk() or | 
|  | *        mbedtls_ssl_conf_psk_cb() or mbedtls_ssl_conf_psk_opaque() | 
|  | *        to configure the PSKs to be used. | 
|  | * | 
|  | * \note  If a pure-ephemeral key exchange mode shall be supported, | 
|  | *        server-side applications must also provide a certificate via | 
|  | *        mbedtls_ssl_conf_own_cert(). | 
|  | * | 
|  | */ | 
|  |  | 
|  | void mbedtls_ssl_conf_tls13_key_exchange_modes(mbedtls_ssl_config *conf, | 
|  | const int kex_modes); | 
|  | #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) | 
|  | #define MBEDTLS_SSL_UNEXPECTED_CID_IGNORE 0 | 
|  | #define MBEDTLS_SSL_UNEXPECTED_CID_FAIL   1 | 
|  | /** | 
|  | * \brief               Specify the length of Connection IDs for incoming | 
|  | *                      encrypted DTLS records, as well as the behaviour | 
|  | *                      on unexpected CIDs. | 
|  | * | 
|  | *                      By default, the CID length is set to \c 0, | 
|  | *                      and unexpected CIDs are silently ignored. | 
|  | * | 
|  | * \param conf          The SSL configuration to modify. | 
|  | * \param len           The length in Bytes of the CID fields in encrypted | 
|  | *                      DTLS records using the CID mechanism. This must | 
|  | *                      not be larger than #MBEDTLS_SSL_CID_OUT_LEN_MAX. | 
|  | * \param ignore_other_cids This determines the stack's behaviour when | 
|  | *                          receiving a record with an unexpected CID. | 
|  | *                          Possible values are: | 
|  | *                          - #MBEDTLS_SSL_UNEXPECTED_CID_IGNORE | 
|  | *                            In this case, the record is silently ignored. | 
|  | *                          - #MBEDTLS_SSL_UNEXPECTED_CID_FAIL | 
|  | *                            In this case, the stack fails with the specific | 
|  | *                            error code #MBEDTLS_ERR_SSL_UNEXPECTED_CID. | 
|  | * | 
|  | * \note                The CID specification allows implementations to either | 
|  | *                      use a common length for all incoming connection IDs or | 
|  | *                      allow variable-length incoming IDs. Mbed TLS currently | 
|  | *                      requires a common length for all connections sharing the | 
|  | *                      same SSL configuration; this allows simpler parsing of | 
|  | *                      record headers. | 
|  | * | 
|  | * \return              \c 0 on success. | 
|  | * \return              #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if \p own_cid_len | 
|  | *                      is too large. | 
|  | */ | 
|  | int mbedtls_ssl_conf_cid(mbedtls_ssl_config *conf, size_t len, | 
|  | int ignore_other_cids); | 
|  | #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | /** | 
|  | * \brief          Set the X.509 security profile used for verification | 
|  | * | 
|  | * \note           The restrictions are enforced for all certificates in the | 
|  | *                 chain. However, signatures in the handshake are not covered | 
|  | *                 by this setting but by \b mbedtls_ssl_conf_sig_hashes(). | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param profile  Profile to use | 
|  | */ | 
|  | void mbedtls_ssl_conf_cert_profile(mbedtls_ssl_config *conf, | 
|  | const mbedtls_x509_crt_profile *profile); | 
|  |  | 
|  | /** | 
|  | * \brief          Set the data required to verify peer certificate | 
|  | * | 
|  | * \note           See \c mbedtls_x509_crt_verify() for notes regarding the | 
|  | *                 parameters ca_chain (maps to trust_ca for that function) | 
|  | *                 and ca_crl. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs) | 
|  | * \param ca_crl   trusted CA CRLs | 
|  | */ | 
|  | void mbedtls_ssl_conf_ca_chain(mbedtls_ssl_config *conf, | 
|  | mbedtls_x509_crt *ca_chain, | 
|  | mbedtls_x509_crl *ca_crl); | 
|  |  | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED) | 
|  | /** | 
|  | * \brief          Set DN hints sent to client in CertificateRequest message | 
|  | * | 
|  | * \note           If not set, subject distinguished names (DNs) are taken | 
|  | *                 from \c mbedtls_ssl_conf_ca_chain() | 
|  | *                 or \c mbedtls_ssl_set_hs_ca_chain()) | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param crt      crt chain whose subject DNs are issuer DNs of client certs | 
|  | *                 from which the client should select client peer certificate. | 
|  | */ | 
|  | static inline | 
|  | void mbedtls_ssl_conf_dn_hints(mbedtls_ssl_config *conf, | 
|  | const mbedtls_x509_crt *crt) | 
|  | { | 
|  | conf->MBEDTLS_PRIVATE(dn_hints) = crt; | 
|  | } | 
|  | #endif /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */ | 
|  |  | 
|  | #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK) | 
|  | /** | 
|  | * \brief          Set the trusted certificate callback. | 
|  | * | 
|  | *                 This API allows to register the set of trusted certificates | 
|  | *                 through a callback, instead of a linked list as configured | 
|  | *                 by mbedtls_ssl_conf_ca_chain(). | 
|  | * | 
|  | *                 This is useful for example in contexts where a large number | 
|  | *                 of CAs are used, and the inefficiency of maintaining them | 
|  | *                 in a linked list cannot be tolerated. It is also useful when | 
|  | *                 the set of trusted CAs needs to be modified frequently. | 
|  | * | 
|  | *                 See the documentation of `mbedtls_x509_crt_ca_cb_t` for | 
|  | *                 more information. | 
|  | * | 
|  | * \param conf     The SSL configuration to register the callback with. | 
|  | * \param f_ca_cb  The trusted certificate callback to use when verifying | 
|  | *                 certificate chains. | 
|  | * \param p_ca_cb  The context to be passed to \p f_ca_cb (for example, | 
|  | *                 a reference to a trusted CA database). | 
|  | * | 
|  | * \note           This API is incompatible with mbedtls_ssl_conf_ca_chain(): | 
|  | *                 Any call to this function overwrites the values set through | 
|  | *                 earlier calls to mbedtls_ssl_conf_ca_chain() or | 
|  | *                 mbedtls_ssl_conf_ca_cb(). | 
|  | * | 
|  | * \note           This API is incompatible with CA indication in | 
|  | *                 CertificateRequest messages: A server-side SSL context which | 
|  | *                 is bound to an SSL configuration that uses a CA callback | 
|  | *                 configured via mbedtls_ssl_conf_ca_cb(), and which requires | 
|  | *                 client authentication, will send an empty CA list in the | 
|  | *                 corresponding CertificateRequest message. | 
|  | * | 
|  | * \note           This API is incompatible with mbedtls_ssl_set_hs_ca_chain(): | 
|  | *                 If an SSL context is bound to an SSL configuration which uses | 
|  | *                 CA callbacks configured via mbedtls_ssl_conf_ca_cb(), then | 
|  | *                 calls to mbedtls_ssl_set_hs_ca_chain() have no effect. | 
|  | * | 
|  | * \note           The use of this API disables the use of restartable ECC | 
|  | *                 during X.509 CRT signature verification (but doesn't affect | 
|  | *                 other uses). | 
|  | * | 
|  | * \warning        This API is incompatible with the use of CRLs. Any call to | 
|  | *                 mbedtls_ssl_conf_ca_cb() unsets CRLs configured through | 
|  | *                 earlier calls to mbedtls_ssl_conf_ca_chain(). | 
|  | * | 
|  | * \warning        In multi-threaded environments, the callback \p f_ca_cb | 
|  | *                 must be thread-safe, and it is the user's responsibility | 
|  | *                 to guarantee this (for example through a mutex | 
|  | *                 contained in the callback context pointed to by \p p_ca_cb). | 
|  | */ | 
|  | void mbedtls_ssl_conf_ca_cb(mbedtls_ssl_config *conf, | 
|  | mbedtls_x509_crt_ca_cb_t f_ca_cb, | 
|  | void *p_ca_cb); | 
|  | #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set own certificate chain and private key | 
|  | * | 
|  | * \note           own_cert should contain in order from the bottom up your | 
|  | *                 certificate chain. The top certificate (self-signed) | 
|  | *                 can be omitted. | 
|  | * | 
|  | * \note           On server, this function can be called multiple times to | 
|  | *                 provision more than one cert/key pair (eg one ECDSA, one | 
|  | *                 RSA with SHA-256, one RSA with SHA-1). An adequate | 
|  | *                 certificate will be selected according to the client's | 
|  | *                 advertised capabilities. In case multiple certificates are | 
|  | *                 adequate, preference is given to the one set by the first | 
|  | *                 call to this function, then second, etc. | 
|  | * | 
|  | * \note           On client, only the first call has any effect. That is, | 
|  | *                 only one client certificate can be provisioned. The | 
|  | *                 server's preferences in its CertificateRequest message will | 
|  | *                 be ignored and our only cert will be sent regardless of | 
|  | *                 whether it matches those preferences - the server can then | 
|  | *                 decide what it wants to do with it. | 
|  | * | 
|  | * \note           The provided \p pk_key needs to match the public key in the | 
|  | *                 first certificate in \p own_cert, or all handshakes using | 
|  | *                 that certificate will fail. It is your responsibility | 
|  | *                 to ensure that; this function will not perform any check. | 
|  | *                 You may use mbedtls_pk_check_pair() in order to perform | 
|  | *                 this check yourself, but be aware that this function can | 
|  | *                 be computationally expensive on some key types. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param own_cert own public certificate chain | 
|  | * \param pk_key   own private key | 
|  | * | 
|  | * \return         0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED | 
|  | */ | 
|  | int mbedtls_ssl_conf_own_cert(mbedtls_ssl_config *conf, | 
|  | mbedtls_x509_crt *own_cert, | 
|  | mbedtls_pk_context *pk_key); | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED) | 
|  | /** | 
|  | * \brief          Configure pre-shared keys (PSKs) and their | 
|  | *                 identities to be used in PSK-based ciphersuites. | 
|  | * | 
|  | *                 Only one PSK can be registered, through either | 
|  | *                 mbedtls_ssl_conf_psk() or mbedtls_ssl_conf_psk_opaque(). | 
|  | *                 If you attempt to register more than one PSK, this function | 
|  | *                 fails, though this may change in future versions, which | 
|  | *                 may add support for multiple PSKs. | 
|  | * | 
|  | * \note           This is mainly useful for clients. Servers will usually | 
|  | *                 want to use \c mbedtls_ssl_conf_psk_cb() instead. | 
|  | * | 
|  | * \note           A PSK set by \c mbedtls_ssl_set_hs_psk() in the PSK callback | 
|  | *                 takes precedence over a PSK configured by this function. | 
|  | * | 
|  | * \param conf     The SSL configuration to register the PSK with. | 
|  | * \param psk      The pointer to the pre-shared key to use. | 
|  | * \param psk_len  The length of the pre-shared key in bytes. | 
|  | * \param psk_identity      The pointer to the pre-shared key identity. | 
|  | * \param psk_identity_len  The length of the pre-shared key identity | 
|  | *                          in bytes. | 
|  | * | 
|  | * \note           The PSK and its identity are copied internally and | 
|  | *                 hence need not be preserved by the caller for the lifetime | 
|  | *                 of the SSL configuration. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no more PSKs | 
|  | *                 can be configured. In this case, the old PSK(s) remain intact. | 
|  | * \return         Another negative error code on other kinds of failure. | 
|  | */ | 
|  | int mbedtls_ssl_conf_psk(mbedtls_ssl_config *conf, | 
|  | const unsigned char *psk, size_t psk_len, | 
|  | const unsigned char *psk_identity, size_t psk_identity_len); | 
|  |  | 
|  | #if defined(MBEDTLS_USE_PSA_CRYPTO) | 
|  | /** | 
|  | * \brief          Configure one or more opaque pre-shared keys (PSKs) and | 
|  | *                 their identities to be used in PSK-based ciphersuites. | 
|  | * | 
|  | *                 Only one PSK can be registered, through either | 
|  | *                 mbedtls_ssl_conf_psk() or mbedtls_ssl_conf_psk_opaque(). | 
|  | *                 If you attempt to register more than one PSK, this function | 
|  | *                 fails, though this may change in future versions, which | 
|  | *                 may add support for multiple PSKs. | 
|  | * | 
|  | * \note           This is mainly useful for clients. Servers will usually | 
|  | *                 want to use \c mbedtls_ssl_conf_psk_cb() instead. | 
|  | * | 
|  | * \note           An opaque PSK set by \c mbedtls_ssl_set_hs_psk_opaque() in | 
|  | *                 the PSK callback takes precedence over an opaque PSK | 
|  | *                 configured by this function. | 
|  | * | 
|  | * \param conf     The SSL configuration to register the PSK with. | 
|  | * \param psk      The identifier of the key slot holding the PSK. | 
|  | *                 Until \p conf is destroyed or this function is successfully | 
|  | *                 called again, the key slot \p psk must be populated with a | 
|  | *                 key of type PSA_ALG_CATEGORY_KEY_DERIVATION whose policy | 
|  | *                 allows its use for the key derivation algorithm applied | 
|  | *                 in the handshake. | 
|  | * \param psk_identity      The pointer to the pre-shared key identity. | 
|  | * \param psk_identity_len  The length of the pre-shared key identity | 
|  | *                          in bytes. | 
|  | * | 
|  | * \note           The PSK identity hint is copied internally and hence need | 
|  | *                 not be preserved by the caller for the lifetime of the | 
|  | *                 SSL configuration. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no more PSKs | 
|  | *                 can be configured. In this case, the old PSK(s) remain intact. | 
|  | * \return         Another negative error code on other kinds of failure. | 
|  | */ | 
|  | int mbedtls_ssl_conf_psk_opaque(mbedtls_ssl_config *conf, | 
|  | mbedtls_svc_key_id_t psk, | 
|  | const unsigned char *psk_identity, | 
|  | size_t psk_identity_len); | 
|  | #endif /* MBEDTLS_USE_PSA_CRYPTO */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set the pre-shared Key (PSK) for the current handshake. | 
|  | * | 
|  | * \note           This should only be called inside the PSK callback, | 
|  | *                 i.e. the function passed to \c mbedtls_ssl_conf_psk_cb(). | 
|  | * | 
|  | * \note           A PSK set by this function takes precedence over a PSK | 
|  | *                 configured by \c mbedtls_ssl_conf_psk(). | 
|  | * | 
|  | * \param ssl      The SSL context to configure a PSK for. | 
|  | * \param psk      The pointer to the pre-shared key. | 
|  | * \param psk_len  The length of the pre-shared key in bytes. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         An \c MBEDTLS_ERR_SSL_XXX error code on failure. | 
|  | */ | 
|  | int mbedtls_ssl_set_hs_psk(mbedtls_ssl_context *ssl, | 
|  | const unsigned char *psk, size_t psk_len); | 
|  |  | 
|  | #if defined(MBEDTLS_USE_PSA_CRYPTO) | 
|  | /** | 
|  | * \brief          Set an opaque pre-shared Key (PSK) for the current handshake. | 
|  | * | 
|  | * \note           This should only be called inside the PSK callback, | 
|  | *                 i.e. the function passed to \c mbedtls_ssl_conf_psk_cb(). | 
|  | * | 
|  | * \note           An opaque PSK set by this function takes precedence over an | 
|  | *                 opaque PSK configured by \c mbedtls_ssl_conf_psk_opaque(). | 
|  | * | 
|  | * \param ssl      The SSL context to configure a PSK for. | 
|  | * \param psk      The identifier of the key slot holding the PSK. | 
|  | *                 For the duration of the current handshake, the key slot | 
|  | *                 must be populated with a key of type | 
|  | *                 PSA_ALG_CATEGORY_KEY_DERIVATION whose policy allows its | 
|  | *                 use for the key derivation algorithm | 
|  | *                 applied in the handshake. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         An \c MBEDTLS_ERR_SSL_XXX error code on failure. | 
|  | */ | 
|  | int mbedtls_ssl_set_hs_psk_opaque(mbedtls_ssl_context *ssl, | 
|  | mbedtls_svc_key_id_t psk); | 
|  | #endif /* MBEDTLS_USE_PSA_CRYPTO */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief          Set the PSK callback (server-side only). | 
|  | * | 
|  | *                 If set, the PSK callback is called for each | 
|  | *                 handshake where a PSK-based ciphersuite was negotiated. | 
|  | *                 The caller provides the identity received and wants to | 
|  | *                 receive the actual PSK data and length. | 
|  | * | 
|  | *                 The callback has the following parameters: | 
|  | *                 - \c void*: The opaque pointer \p p_psk. | 
|  | *                 - \c mbedtls_ssl_context*: The SSL context to which | 
|  | *                                            the operation applies. | 
|  | *                 - \c const unsigned char*: The PSK identity | 
|  | *                                            selected by the client. | 
|  | *                 - \c size_t: The length of the PSK identity | 
|  | *                              selected by the client. | 
|  | * | 
|  | *                 If a valid PSK identity is found, the callback should use | 
|  | *                 \c mbedtls_ssl_set_hs_psk() or | 
|  | *                 \c mbedtls_ssl_set_hs_psk_opaque() | 
|  | *                 on the SSL context to set the correct PSK and return \c 0. | 
|  | *                 Any other return value will result in a denied PSK identity. | 
|  | * | 
|  | * \note           A dynamic PSK (i.e. set by the PSK callback) takes | 
|  | *                 precedence over a static PSK (i.e. set by | 
|  | *                 \c mbedtls_ssl_conf_psk() or | 
|  | *                 \c mbedtls_ssl_conf_psk_opaque()). | 
|  | *                 This means that if you set a PSK callback using this | 
|  | *                 function, you don't need to set a PSK using | 
|  | *                 \c mbedtls_ssl_conf_psk() or | 
|  | *                 \c mbedtls_ssl_conf_psk_opaque()). | 
|  | * | 
|  | * \param conf     The SSL configuration to register the callback with. | 
|  | * \param f_psk    The callback for selecting and setting the PSK based | 
|  | *                 in the PSK identity chosen by the client. | 
|  | * \param p_psk    A pointer to an opaque structure to be passed to | 
|  | *                 the callback, for example a PSK store. | 
|  | */ | 
|  | void mbedtls_ssl_conf_psk_cb(mbedtls_ssl_config *conf, | 
|  | int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, | 
|  | size_t), | 
|  | void *p_psk); | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  | #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_PSK_ENABLED */ | 
|  |  | 
|  | #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief          Set the Diffie-Hellman public P and G values | 
|  | *                 from big-endian binary presentations. | 
|  | *                 (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN) | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param dhm_P    Diffie-Hellman-Merkle modulus in big-endian binary form | 
|  | * \param P_len    Length of DHM modulus | 
|  | * \param dhm_G    Diffie-Hellman-Merkle generator in big-endian binary form | 
|  | * \param G_len    Length of DHM generator | 
|  | * | 
|  | * \return         0 if successful | 
|  | */ | 
|  | int mbedtls_ssl_conf_dh_param_bin(mbedtls_ssl_config *conf, | 
|  | const unsigned char *dhm_P, size_t P_len, | 
|  | const unsigned char *dhm_G,  size_t G_len); | 
|  |  | 
|  | /** | 
|  | * \brief          Set the Diffie-Hellman public P and G values, | 
|  | *                 read from existing context (server-side only) | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param dhm_ctx  Diffie-Hellman-Merkle context | 
|  | * | 
|  | * \return         0 if successful | 
|  | */ | 
|  | int mbedtls_ssl_conf_dh_param_ctx(mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx); | 
|  | #endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */ | 
|  |  | 
|  | #if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C) | 
|  | /** | 
|  | * \brief          Set the minimum length for Diffie-Hellman parameters. | 
|  | *                 (Client-side only.) | 
|  | *                 (Default: 1024 bits.) | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param bitlen   Minimum bit length of the DHM prime | 
|  | */ | 
|  | void mbedtls_ssl_conf_dhm_min_bitlen(mbedtls_ssl_config *conf, | 
|  | unsigned int bitlen); | 
|  | #endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_ECP_LIGHT) | 
|  | #if !defined(MBEDTLS_DEPRECATED_REMOVED) | 
|  | /** | 
|  | * \brief          Set the allowed curves in order of preference. | 
|  | * | 
|  | *                 On server: this only affects selection of the ECDHE curve; | 
|  | *                 the curves used for ECDH and ECDSA are determined by the | 
|  | *                 list of available certificates instead. | 
|  | * | 
|  | *                 On client: this affects the list of curves offered for any | 
|  | *                 use. The server can override our preference order. | 
|  | * | 
|  | *                 Both sides: limits the set of curves accepted for use in | 
|  | *                 ECDHE and in the peer's end-entity certificate. | 
|  | * | 
|  | * \deprecated     Superseded by mbedtls_ssl_conf_groups(). | 
|  | * | 
|  | * \note           This has no influence on which curves are allowed inside the | 
|  | *                 certificate chains, see \c mbedtls_ssl_conf_cert_profile() | 
|  | *                 for that. For the end-entity certificate however, the key | 
|  | *                 will be accepted only if it is allowed both by this list | 
|  | *                 and by the cert profile. | 
|  | * | 
|  | * \note           This list should be ordered by decreasing preference | 
|  | *                 (preferred curve first). | 
|  | * | 
|  | * \note           The default list is the same set of curves that | 
|  | *                 #mbedtls_x509_crt_profile_default allows, plus | 
|  | *                 ECDHE-only curves selected according to the same criteria. | 
|  | *                 The order favors curves with the lowest resource usage. | 
|  | * | 
|  | * \note           New minor versions of Mbed TLS may extend this list, | 
|  | *                 for example if new curves are added to the library. | 
|  | *                 New minor versions of Mbed TLS will not remove items | 
|  | *                 from this list unless serious security concerns require it. | 
|  | *                 New minor versions of Mbed TLS may change the order in | 
|  | *                 keeping with the general principle of favoring the lowest | 
|  | *                 resource usage. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param curves   Ordered list of allowed curves, | 
|  | *                 terminated by MBEDTLS_ECP_DP_NONE. | 
|  | */ | 
|  | void MBEDTLS_DEPRECATED mbedtls_ssl_conf_curves(mbedtls_ssl_config *conf, | 
|  | const mbedtls_ecp_group_id *curves); | 
|  | #endif /* MBEDTLS_DEPRECATED_REMOVED */ | 
|  | #endif /* MBEDTLS_ECP_LIGHT */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set the allowed groups in order of preference. | 
|  | * | 
|  | *                 On server: This only affects the choice of key agreement mechanism | 
|  | * | 
|  | *                 On client: this affects the list of groups offered for any | 
|  | *                 use. The server can override our preference order. | 
|  | * | 
|  | *                 Both sides: limits the set of groups accepted for use in | 
|  | *                 key sharing. | 
|  | * | 
|  | * \note           This function replaces the deprecated mbedtls_ssl_conf_curves(), | 
|  | *                 which only allows ECP curves to be configured. | 
|  | * | 
|  | * \note           The most recent invocation of either mbedtls_ssl_conf_curves() | 
|  | *                 or mbedtls_ssl_conf_groups() nullifies all previous invocations | 
|  | *                 of both. | 
|  | * | 
|  | * \note           This list should be ordered by decreasing preference | 
|  | *                 (preferred group first). | 
|  | * | 
|  | * \note           When this function is not called, a default list is used, | 
|  | *                 consisting of all supported curves at 255 bits and above, | 
|  | *                 and all supported finite fields at 2048 bits and above. | 
|  | *                 The order favors groups with the lowest resource usage. | 
|  | * | 
|  | * \note           New minor versions of Mbed TLS will not remove items | 
|  | *                 from the default list unless serious security concerns require it. | 
|  | *                 New minor versions of Mbed TLS may change the order in | 
|  | *                 keeping with the general principle of favoring the lowest | 
|  | *                 resource usage. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param groups   List of allowed groups ordered by preference, terminated by 0. | 
|  | *                 Must contain valid IANA NamedGroup IDs (provided via either an integer | 
|  | *                 or using MBEDTLS_TLS1_3_NAMED_GROUP_XXX macros). | 
|  | */ | 
|  | void mbedtls_ssl_conf_groups(mbedtls_ssl_config *conf, | 
|  | const uint16_t *groups); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED) | 
|  | #if !defined(MBEDTLS_DEPRECATED_REMOVED) && defined(MBEDTLS_SSL_PROTO_TLS1_2) | 
|  | /** | 
|  | * \brief          Set the allowed hashes for signatures during the handshake. | 
|  | * | 
|  | * \note           This only affects which hashes are offered and can be used | 
|  | *                 for signatures during the handshake. Hashes for message | 
|  | *                 authentication and the TLS PRF are controlled by the | 
|  | *                 ciphersuite, see \c mbedtls_ssl_conf_ciphersuites(). Hashes | 
|  | *                 used for certificate signature are controlled by the | 
|  | *                 verification profile, see \c mbedtls_ssl_conf_cert_profile(). | 
|  | * | 
|  | * \note           This list should be ordered by decreasing preference | 
|  | *                 (preferred hash first). | 
|  | * | 
|  | * \note           By default, all supported hashes whose length is at least | 
|  | *                 256 bits are allowed. This is the same set as the default | 
|  | *                 for certificate verification | 
|  | *                 (#mbedtls_x509_crt_profile_default). | 
|  | *                 The preference order is currently unspecified and may | 
|  | *                 change in future versions. | 
|  | * | 
|  | * \note           New minor versions of Mbed TLS may extend this list, | 
|  | *                 for example if new curves are added to the library. | 
|  | *                 New minor versions of Mbed TLS will not remove items | 
|  | *                 from this list unless serious security concerns require it. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param hashes   Ordered list of allowed signature hashes, | 
|  | *                 terminated by \c MBEDTLS_MD_NONE. | 
|  | */ | 
|  | void MBEDTLS_DEPRECATED mbedtls_ssl_conf_sig_hashes(mbedtls_ssl_config *conf, | 
|  | const int *hashes); | 
|  | #endif /* !MBEDTLS_DEPRECATED_REMOVED && MBEDTLS_SSL_PROTO_TLS1_2 */ | 
|  |  | 
|  | /** | 
|  | * \brief          Configure allowed signature algorithms for use in TLS 1.3 | 
|  | * | 
|  | * \param conf     The SSL configuration to use. | 
|  | * \param sig_algs List of allowed IANA values for TLS 1.3 signature algorithms, | 
|  | *                 terminated by \c MBEDTLS_TLS1_3_SIG_NONE. The list must remain | 
|  | *                 available throughout the lifetime of the conf object. Supported | 
|  | *                 values are available as \c MBEDTLS_TLS1_3_SIG_XXXX | 
|  | */ | 
|  | void mbedtls_ssl_conf_sig_algs(mbedtls_ssl_config *conf, | 
|  | const uint16_t *sig_algs); | 
|  | #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */ | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | /** | 
|  | * \brief          Set or reset the hostname to check against the received | 
|  | *                 server certificate. It sets the ServerName TLS extension, | 
|  | *                 too, if that extension is enabled. (client-side only) | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param hostname the server hostname, may be NULL to clear hostname | 
|  |  | 
|  | * \note           Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN. | 
|  | * | 
|  | * \return         0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on | 
|  | *                 allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on | 
|  | *                 too long input hostname. | 
|  | * | 
|  | *                 Hostname set to the one provided on success (cleared | 
|  | *                 when NULL). On allocation failure hostname is cleared. | 
|  | *                 On too long input failure, old hostname is unchanged. | 
|  | */ | 
|  | int mbedtls_ssl_set_hostname(mbedtls_ssl_context *ssl, const char *hostname); | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) | 
|  | /** | 
|  | * \brief          Retrieve SNI extension value for the current handshake. | 
|  | *                 Available in \p f_cert_cb of \c mbedtls_ssl_conf_cert_cb(), | 
|  | *                 this is the same value passed to \p f_sni callback of | 
|  | *                 \c mbedtls_ssl_conf_sni() and may be used instead of | 
|  | *                 \c mbedtls_ssl_conf_sni(). | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param name_len pointer into which to store length of returned value. | 
|  | *                 0 if SNI extension is not present or not yet processed. | 
|  | * | 
|  | * \return         const pointer to SNI extension value. | 
|  | *                 - value is valid only when called in \p f_cert_cb | 
|  | *                   registered with \c mbedtls_ssl_conf_cert_cb(). | 
|  | *                 - value is NULL if SNI extension is not present. | 
|  | *                 - value is not '\0'-terminated.  Use \c name_len for len. | 
|  | *                 - value must not be freed. | 
|  | */ | 
|  | const unsigned char *mbedtls_ssl_get_hs_sni(mbedtls_ssl_context *ssl, | 
|  | size_t *name_len); | 
|  |  | 
|  | /** | 
|  | * \brief          Set own certificate and key for the current handshake | 
|  | * | 
|  | * \note           Same as \c mbedtls_ssl_conf_own_cert() but for use within | 
|  | *                 the SNI callback or the certificate selection callback. | 
|  | * | 
|  | * \note           Passing null \c own_cert clears the certificate list for | 
|  | *                 the current handshake. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param own_cert own public certificate chain | 
|  | * \param pk_key   own private key | 
|  | * | 
|  | * \return         0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED | 
|  | */ | 
|  | int mbedtls_ssl_set_hs_own_cert(mbedtls_ssl_context *ssl, | 
|  | mbedtls_x509_crt *own_cert, | 
|  | mbedtls_pk_context *pk_key); | 
|  |  | 
|  | /** | 
|  | * \brief          Set the data required to verify peer certificate for the | 
|  | *                 current handshake | 
|  | * | 
|  | * \note           Same as \c mbedtls_ssl_conf_ca_chain() but for use within | 
|  | *                 the SNI callback or the certificate selection callback. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs) | 
|  | * \param ca_crl   trusted CA CRLs | 
|  | */ | 
|  | void mbedtls_ssl_set_hs_ca_chain(mbedtls_ssl_context *ssl, | 
|  | mbedtls_x509_crt *ca_chain, | 
|  | mbedtls_x509_crl *ca_crl); | 
|  |  | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED) | 
|  | /** | 
|  | * \brief          Set DN hints sent to client in CertificateRequest message | 
|  | * | 
|  | * \note           Same as \c mbedtls_ssl_conf_dn_hints() but for use within | 
|  | *                 the SNI callback or the certificate selection callback. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param crt      crt chain whose subject DNs are issuer DNs of client certs | 
|  | *                 from which the client should select client peer certificate. | 
|  | */ | 
|  | void mbedtls_ssl_set_hs_dn_hints(mbedtls_ssl_context *ssl, | 
|  | const mbedtls_x509_crt *crt); | 
|  | #endif /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set authmode for the current handshake. | 
|  | * | 
|  | * \note           Same as \c mbedtls_ssl_conf_authmode() but for use within | 
|  | *                 the SNI callback or the certificate selection callback. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param authmode MBEDTLS_SSL_VERIFY_NONE, MBEDTLS_SSL_VERIFY_OPTIONAL or | 
|  | *                 MBEDTLS_SSL_VERIFY_REQUIRED | 
|  | */ | 
|  | void mbedtls_ssl_set_hs_authmode(mbedtls_ssl_context *ssl, | 
|  | int authmode); | 
|  |  | 
|  | /** | 
|  | * \brief          Set server side ServerName TLS extension callback | 
|  | *                 (optional, server-side only). | 
|  | * | 
|  | *                 If set, the ServerName callback is called whenever the | 
|  | *                 server receives a ServerName TLS extension from the client | 
|  | *                 during a handshake. The ServerName callback has the | 
|  | *                 following parameters: (void *parameter, mbedtls_ssl_context *ssl, | 
|  | *                 const unsigned char *hostname, size_t len). If a suitable | 
|  | *                 certificate is found, the callback must set the | 
|  | *                 certificate(s) and key(s) to use with \c | 
|  | *                 mbedtls_ssl_set_hs_own_cert() (can be called repeatedly), | 
|  | *                 and may optionally adjust the CA and associated CRL with \c | 
|  | *                 mbedtls_ssl_set_hs_ca_chain() as well as the client | 
|  | *                 authentication mode with \c mbedtls_ssl_set_hs_authmode(), | 
|  | *                 then must return 0. If no matching name is found, the | 
|  | *                 callback may return non-zero to abort the handshake. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param f_sni    verification function | 
|  | * \param p_sni    verification parameter | 
|  | */ | 
|  | void mbedtls_ssl_conf_sni(mbedtls_ssl_config *conf, | 
|  | int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, | 
|  | size_t), | 
|  | void *p_sni); | 
|  | #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */ | 
|  |  | 
|  | #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) | 
|  | /** | 
|  | * \brief          Set the EC J-PAKE password for current handshake. | 
|  | * | 
|  | * \note           An internal copy is made, and destroyed as soon as the | 
|  | *                 handshake is completed, or when the SSL context is reset or | 
|  | *                 freed. | 
|  | * | 
|  | * \note           The SSL context needs to be already set up. The right place | 
|  | *                 to call this function is between \c mbedtls_ssl_setup() or | 
|  | *                 \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake(). | 
|  | *                 Password cannot be empty (see RFC 8236). | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param pw       EC J-PAKE password (pre-shared secret). It cannot be empty | 
|  | * \param pw_len   length of pw in bytes | 
|  | * | 
|  | * \return         0 on success, or a negative error code. | 
|  | */ | 
|  | int mbedtls_ssl_set_hs_ecjpake_password(mbedtls_ssl_context *ssl, | 
|  | const unsigned char *pw, | 
|  | size_t pw_len); | 
|  |  | 
|  | /** | 
|  | * \brief          Set the EC J-PAKE opaque password for current handshake. | 
|  | * | 
|  | * \note           The key must remain valid until the handshake is over. | 
|  | * | 
|  | * \note           The SSL context needs to be already set up. The right place | 
|  | *                 to call this function is between \c mbedtls_ssl_setup() or | 
|  | *                 \c mbedtls_ssl_reset() and \c mbedtls_ssl_handshake(). | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param pwd      EC J-PAKE opaque password | 
|  | * | 
|  | * \return         0 on success, or a negative error code. | 
|  | */ | 
|  | int mbedtls_ssl_set_hs_ecjpake_password_opaque(mbedtls_ssl_context *ssl, | 
|  | mbedtls_svc_key_id_t pwd); | 
|  | #endif /*MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_ALPN) | 
|  | /** | 
|  | * \brief          Set the supported Application Layer Protocols. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param protos   Pointer to a NULL-terminated list of supported protocols, | 
|  | *                 in decreasing preference order. The pointer to the list is | 
|  | *                 recorded by the library for later reference as required, so | 
|  | *                 the lifetime of the table must be at least as long as the | 
|  | *                 lifetime of the SSL configuration structure. | 
|  | * | 
|  | * \return         0 on success, or MBEDTLS_ERR_SSL_BAD_INPUT_DATA. | 
|  | */ | 
|  | int mbedtls_ssl_conf_alpn_protocols(mbedtls_ssl_config *conf, const char **protos); | 
|  |  | 
|  | /** | 
|  | * \brief          Get the name of the negotiated Application Layer Protocol. | 
|  | *                 This function should be called after the handshake is | 
|  | *                 completed. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         Protocol name, or NULL if no protocol was negotiated. | 
|  | */ | 
|  | const char *mbedtls_ssl_get_alpn_protocol(const mbedtls_ssl_context *ssl); | 
|  | #endif /* MBEDTLS_SSL_ALPN */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_DTLS_SRTP) | 
|  | #if defined(MBEDTLS_DEBUG_C) | 
|  | static inline const char *mbedtls_ssl_get_srtp_profile_as_string(mbedtls_ssl_srtp_profile profile) | 
|  | { | 
|  | switch (profile) { | 
|  | case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80: | 
|  | return "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80"; | 
|  | case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32: | 
|  | return "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32"; | 
|  | case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80: | 
|  | return "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80"; | 
|  | case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32: | 
|  | return "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32"; | 
|  | default: break; | 
|  | } | 
|  | return ""; | 
|  | } | 
|  | #endif /* MBEDTLS_DEBUG_C */ | 
|  | /** | 
|  | * \brief                   Manage support for mki(master key id) value | 
|  | *                          in use_srtp extension. | 
|  | *                          MKI is an optional part of SRTP used for key management | 
|  | *                          and re-keying. See RFC3711 section 3.1 for details. | 
|  | *                          The default value is | 
|  | *                          #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED. | 
|  | * | 
|  | * \param conf              The SSL configuration to manage mki support. | 
|  | * \param support_mki_value Enable or disable mki usage. Values are | 
|  | *                          #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED | 
|  | *                          or #MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED. | 
|  | */ | 
|  | void mbedtls_ssl_conf_srtp_mki_value_supported(mbedtls_ssl_config *conf, | 
|  | int support_mki_value); | 
|  |  | 
|  | /** | 
|  | * \brief                   Set the supported DTLS-SRTP protection profiles. | 
|  | * | 
|  | * \param conf              SSL configuration | 
|  | * \param profiles          Pointer to a List of MBEDTLS_TLS_SRTP_UNSET terminated | 
|  | *                          supported protection profiles | 
|  | *                          in decreasing preference order. | 
|  | *                          The pointer to the list is recorded by the library | 
|  | *                          for later reference as required, so the lifetime | 
|  | *                          of the table must be at least as long as the lifetime | 
|  | *                          of the SSL configuration structure. | 
|  | *                          The list must not hold more than | 
|  | *                          MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH elements | 
|  | *                          (excluding the terminating MBEDTLS_TLS_SRTP_UNSET). | 
|  | * | 
|  | * \return                  0 on success | 
|  | * \return                  #MBEDTLS_ERR_SSL_BAD_INPUT_DATA when the list of | 
|  | *                          protection profiles is incorrect. | 
|  | */ | 
|  | int mbedtls_ssl_conf_dtls_srtp_protection_profiles | 
|  | (mbedtls_ssl_config *conf, | 
|  | const mbedtls_ssl_srtp_profile *profiles); | 
|  |  | 
|  | /** | 
|  | * \brief                  Set the mki_value for the current DTLS-SRTP session. | 
|  | * | 
|  | * \param ssl              SSL context to use. | 
|  | * \param mki_value        The MKI value to set. | 
|  | * \param mki_len          The length of the MKI value. | 
|  | * | 
|  | * \note                   This function is relevant on client side only. | 
|  | *                         The server discovers the mki value during handshake. | 
|  | *                         A mki value set on server side using this function | 
|  | *                         is ignored. | 
|  | * | 
|  | * \return                 0 on success | 
|  | * \return                 #MBEDTLS_ERR_SSL_BAD_INPUT_DATA | 
|  | * \return                 #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE | 
|  | */ | 
|  | int mbedtls_ssl_dtls_srtp_set_mki_value(mbedtls_ssl_context *ssl, | 
|  | unsigned char *mki_value, | 
|  | uint16_t mki_len); | 
|  | /** | 
|  | * \brief                  Get the negotiated DTLS-SRTP information: | 
|  | *                         Protection profile and MKI value. | 
|  | * | 
|  | * \warning                This function must be called after the handshake is | 
|  | *                         completed. The value returned by this function must | 
|  | *                         not be trusted or acted upon before the handshake completes. | 
|  | * | 
|  | * \param ssl              The SSL context to query. | 
|  | * \param dtls_srtp_info   The negotiated DTLS-SRTP information: | 
|  | *                         - Protection profile in use. | 
|  | *                         A direct mapping of the iana defined value for protection | 
|  | *                         profile on an uint16_t. | 
|  | http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml | 
|  | *                         #MBEDTLS_TLS_SRTP_UNSET if the use of SRTP was not negotiated | 
|  | *                         or peer's Hello packet was not parsed yet. | 
|  | *                         - mki size and value( if size is > 0 ). | 
|  | */ | 
|  | void mbedtls_ssl_get_dtls_srtp_negotiation_result(const mbedtls_ssl_context *ssl, | 
|  | mbedtls_dtls_srtp_info *dtls_srtp_info); | 
|  | #endif /* MBEDTLS_SSL_DTLS_SRTP */ | 
|  |  | 
|  | #if !defined(MBEDTLS_DEPRECATED_REMOVED) | 
|  | /** | 
|  | * \brief          Set the maximum supported version sent from the client side | 
|  | *                 and/or accepted at the server side. | 
|  | * | 
|  | *                 See also the documentation of mbedtls_ssl_conf_min_version(). | 
|  | * | 
|  | * \note           This ignores ciphersuites from higher versions. | 
|  | * | 
|  | * \note           This function is deprecated and has been replaced by | 
|  | *                 \c mbedtls_ssl_conf_max_tls_version(). | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param major    Major version number (#MBEDTLS_SSL_MAJOR_VERSION_3) | 
|  | * \param minor    Minor version number | 
|  | *                 (#MBEDTLS_SSL_MINOR_VERSION_3 for (D)TLS 1.2, | 
|  | *                 #MBEDTLS_SSL_MINOR_VERSION_4 for TLS 1.3) | 
|  | */ | 
|  | void MBEDTLS_DEPRECATED mbedtls_ssl_conf_max_version(mbedtls_ssl_config *conf, int major, | 
|  | int minor); | 
|  | #endif /* MBEDTLS_DEPRECATED_REMOVED */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set the maximum supported version sent from the client side | 
|  | *                 and/or accepted at the server side. | 
|  | * | 
|  | * \note           After the handshake, you can call | 
|  | *                 mbedtls_ssl_get_version_number() to see what version was | 
|  | *                 negotiated. | 
|  | * | 
|  | * \param conf         SSL configuration | 
|  | * \param tls_version  TLS protocol version number (\p mbedtls_ssl_protocol_version) | 
|  | *                     (#MBEDTLS_SSL_VERSION_UNKNOWN is not valid) | 
|  | */ | 
|  | static inline void mbedtls_ssl_conf_max_tls_version(mbedtls_ssl_config *conf, | 
|  | mbedtls_ssl_protocol_version tls_version) | 
|  | { | 
|  | conf->MBEDTLS_PRIVATE(max_tls_version) = tls_version; | 
|  | } | 
|  |  | 
|  | #if !defined(MBEDTLS_DEPRECATED_REMOVED) | 
|  | /** | 
|  | * \brief          Set the minimum accepted SSL/TLS protocol version | 
|  | * | 
|  | * \note           By default, all supported versions are accepted. | 
|  | *                 Future versions of the library may disable older | 
|  | *                 protocol versions by default if they become deprecated. | 
|  | * | 
|  | * \note           The following versions are supported (if enabled at | 
|  | *                 compile time): | 
|  | *                 - (D)TLS 1.2: \p major = #MBEDTLS_SSL_MAJOR_VERSION_3, | 
|  | *                   \p minor = #MBEDTLS_SSL_MINOR_VERSION_3 | 
|  | *                 - TLS 1.3: \p major = #MBEDTLS_SSL_MAJOR_VERSION_3, | 
|  | *                   \p minor = #MBEDTLS_SSL_MINOR_VERSION_4 | 
|  | * | 
|  | *                 Note that the numbers in the constant names are the | 
|  | *                 TLS internal protocol numbers, and the minor versions | 
|  | *                 differ by one from the human-readable versions! | 
|  | * | 
|  | * \note           Input outside of the SSL_MAX_XXXXX_VERSION and | 
|  | *                 SSL_MIN_XXXXX_VERSION range is ignored. | 
|  | * | 
|  | * \note           After the handshake, you can call | 
|  | *                 mbedtls_ssl_get_version_number() to see what version was | 
|  | *                 negotiated. | 
|  | * | 
|  | * \note           This function is deprecated and has been replaced by | 
|  | *                 \c mbedtls_ssl_conf_min_tls_version(). | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param major    Major version number (#MBEDTLS_SSL_MAJOR_VERSION_3) | 
|  | * \param minor    Minor version number | 
|  | *                 (#MBEDTLS_SSL_MINOR_VERSION_3 for (D)TLS 1.2, | 
|  | *                 #MBEDTLS_SSL_MINOR_VERSION_4 for TLS 1.3) | 
|  | */ | 
|  | void MBEDTLS_DEPRECATED mbedtls_ssl_conf_min_version(mbedtls_ssl_config *conf, int major, | 
|  | int minor); | 
|  | #endif /* MBEDTLS_DEPRECATED_REMOVED */ | 
|  |  | 
|  | /** | 
|  | * \brief          Set the minimum supported version sent from the client side | 
|  | *                 and/or accepted at the server side. | 
|  | * | 
|  | * \note           After the handshake, you can call | 
|  | *                 mbedtls_ssl_get_version_number() to see what version was | 
|  | *                 negotiated. | 
|  | * | 
|  | * \param conf         SSL configuration | 
|  | * \param tls_version  TLS protocol version number (\p mbedtls_ssl_protocol_version) | 
|  | *                     (#MBEDTLS_SSL_VERSION_UNKNOWN is not valid) | 
|  | */ | 
|  | static inline void mbedtls_ssl_conf_min_tls_version(mbedtls_ssl_config *conf, | 
|  | mbedtls_ssl_protocol_version tls_version) | 
|  | { | 
|  | conf->MBEDTLS_PRIVATE(min_tls_version) = tls_version; | 
|  | } | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) | 
|  | /** | 
|  | * \brief           Enable or disable Encrypt-then-MAC | 
|  | *                  (Default: MBEDTLS_SSL_ETM_ENABLED) | 
|  | * | 
|  | * \note            This should always be enabled, it is a security | 
|  | *                  improvement, and should not cause any interoperability | 
|  | *                  issue (used only if the peer supports it too). | 
|  | * | 
|  | * \param conf      SSL configuration | 
|  | * \param etm       MBEDTLS_SSL_ETM_ENABLED or MBEDTLS_SSL_ETM_DISABLED | 
|  | */ | 
|  | void mbedtls_ssl_conf_encrypt_then_mac(mbedtls_ssl_config *conf, char etm); | 
|  | #endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) | 
|  | /** | 
|  | * \brief           Enable or disable Extended Master Secret negotiation. | 
|  | *                  (Default: MBEDTLS_SSL_EXTENDED_MS_ENABLED) | 
|  | * | 
|  | * \note            This should always be enabled, it is a security fix to the | 
|  | *                  protocol, and should not cause any interoperability issue | 
|  | *                  (used only if the peer supports it too). | 
|  | * | 
|  | * \param conf      SSL configuration | 
|  | * \param ems       MBEDTLS_SSL_EXTENDED_MS_ENABLED or MBEDTLS_SSL_EXTENDED_MS_DISABLED | 
|  | */ | 
|  | void mbedtls_ssl_conf_extended_master_secret(mbedtls_ssl_config *conf, char ems); | 
|  | #endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief          Whether to send a list of acceptable CAs in | 
|  | *                 CertificateRequest messages. | 
|  | *                 (Default: do send) | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param cert_req_ca_list   MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or | 
|  | *                          MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED | 
|  | */ | 
|  | void mbedtls_ssl_conf_cert_req_ca_list(mbedtls_ssl_config *conf, | 
|  | char cert_req_ca_list); | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) | 
|  | /** | 
|  | * \brief          Set the maximum fragment length to emit and/or negotiate. | 
|  | *                 (Typical: the smaller of #MBEDTLS_SSL_IN_CONTENT_LEN and | 
|  | *                 #MBEDTLS_SSL_OUT_CONTENT_LEN, usually `2^14` bytes) | 
|  | *                 (Server: set maximum fragment length to emit, | 
|  | *                 usually negotiated by the client during handshake) | 
|  | *                 (Client: set maximum fragment length to emit *and* | 
|  | *                 negotiate with the server during handshake) | 
|  | *                 (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE) | 
|  | * | 
|  | * \note           On the client side, the maximum fragment length extension | 
|  | *                 *will not* be used, unless the maximum fragment length has | 
|  | *                 been set via this function to a value different than | 
|  | *                 #MBEDTLS_SSL_MAX_FRAG_LEN_NONE. | 
|  | * | 
|  | * \note           With TLS, this currently only affects ApplicationData (sent | 
|  | *                 with \c mbedtls_ssl_read()), not handshake messages. | 
|  | *                 With DTLS, this affects both ApplicationData and handshake. | 
|  | * | 
|  | * \note           This sets the maximum length for a record's payload, | 
|  | *                 excluding record overhead that will be added to it, see | 
|  | *                 \c mbedtls_ssl_get_record_expansion(). | 
|  | * | 
|  | * \note           For DTLS, it is also possible to set a limit for the total | 
|  | *                 size of datagrams passed to the transport layer, including | 
|  | *                 record overhead, see \c mbedtls_ssl_set_mtu(). | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param mfl_code Code for maximum fragment length (allowed values: | 
|  | *                 MBEDTLS_SSL_MAX_FRAG_LEN_512,  MBEDTLS_SSL_MAX_FRAG_LEN_1024, | 
|  | *                 MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096) | 
|  | * | 
|  | * \return         0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA | 
|  | */ | 
|  | int mbedtls_ssl_conf_max_frag_len(mbedtls_ssl_config *conf, unsigned char mfl_code); | 
|  | #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief          Pick the ciphersuites order according to the second parameter | 
|  | *                 in the SSL Server module (MBEDTLS_SSL_SRV_C). | 
|  | *                 (Default, if never called: MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER) | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param order    Server or client (MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_SERVER | 
|  | *                                or MBEDTLS_SSL_SRV_CIPHERSUITE_ORDER_CLIENT) | 
|  | */ | 
|  | void mbedtls_ssl_conf_preference_order(mbedtls_ssl_config *conf, int order); | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SESSION_TICKETS) && \ | 
|  | defined(MBEDTLS_SSL_CLI_C) | 
|  | /** | 
|  | * \brief          Enable / Disable session tickets (client only). | 
|  | *                 (Default: MBEDTLS_SSL_SESSION_TICKETS_ENABLED.) | 
|  | * | 
|  | * \note           On server, use \c mbedtls_ssl_conf_session_tickets_cb(). | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param use_tickets   Enable or disable (MBEDTLS_SSL_SESSION_TICKETS_ENABLED or | 
|  | *                                         MBEDTLS_SSL_SESSION_TICKETS_DISABLED) | 
|  | */ | 
|  | void mbedtls_ssl_conf_session_tickets(mbedtls_ssl_config *conf, int use_tickets); | 
|  | #endif /* MBEDTLS_SSL_SESSION_TICKETS && | 
|  | MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SESSION_TICKETS) && \ | 
|  | defined(MBEDTLS_SSL_SRV_C) && \ | 
|  | defined(MBEDTLS_SSL_PROTO_TLS1_3) | 
|  | /** | 
|  | * \brief   Number of NewSessionTicket messages for the server to send | 
|  | *          after handshake completion. | 
|  | * | 
|  | * \note    The default value is | 
|  | *          \c MBEDTLS_SSL_TLS1_3_DEFAULT_NEW_SESSION_TICKETS. | 
|  | * | 
|  | * \note    In case of a session resumption, this setting only partially apply. | 
|  | *          At most one ticket is sent in that case to just renew the pool of | 
|  | *          tickets of the client. The rationale is to avoid the number of | 
|  | *          tickets on the server to become rapidly out of control when the | 
|  | *          server has the same configuration for all its connection instances. | 
|  | * | 
|  | * \param conf    SSL configuration | 
|  | * \param num_tickets    Number of NewSessionTicket. | 
|  | * | 
|  | */ | 
|  | void mbedtls_ssl_conf_new_session_tickets(mbedtls_ssl_config *conf, | 
|  | uint16_t num_tickets); | 
|  | #endif /* MBEDTLS_SSL_SESSION_TICKETS && | 
|  | MBEDTLS_SSL_SRV_C && | 
|  | MBEDTLS_SSL_PROTO_TLS1_3*/ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_RENEGOTIATION) | 
|  | /** | 
|  | * \brief          Enable / Disable renegotiation support for connection when | 
|  | *                 initiated by peer | 
|  | *                 (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED) | 
|  | * | 
|  | * \warning        It is recommended to always disable renegotiation unless you | 
|  | *                 know you need it and you know what you're doing. In the | 
|  | *                 past, there have been several issues associated with | 
|  | *                 renegotiation or a poor understanding of its properties. | 
|  | * | 
|  | * \note           Server-side, enabling renegotiation also makes the server | 
|  | *                 susceptible to a resource DoS by a malicious client. | 
|  | * | 
|  | * \param conf    SSL configuration | 
|  | * \param renegotiation     Enable or disable (MBEDTLS_SSL_RENEGOTIATION_ENABLED or | 
|  | *                                             MBEDTLS_SSL_RENEGOTIATION_DISABLED) | 
|  | */ | 
|  | void mbedtls_ssl_conf_renegotiation(mbedtls_ssl_config *conf, int renegotiation); | 
|  | #endif /* MBEDTLS_SSL_RENEGOTIATION */ | 
|  |  | 
|  | /** | 
|  | * \brief          Prevent or allow legacy renegotiation. | 
|  | *                 (Default: MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION) | 
|  | * | 
|  | *                 MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION allows connections to | 
|  | *                 be established even if the peer does not support | 
|  | *                 secure renegotiation, but does not allow renegotiation | 
|  | *                 to take place if not secure. | 
|  | *                 (Interoperable and secure option) | 
|  | * | 
|  | *                 MBEDTLS_SSL_LEGACY_ALLOW_RENEGOTIATION allows renegotiations | 
|  | *                 with non-upgraded peers. Allowing legacy renegotiation | 
|  | *                 makes the connection vulnerable to specific man in the | 
|  | *                 middle attacks. (See RFC 5746) | 
|  | *                 (Most interoperable and least secure option) | 
|  | * | 
|  | *                 MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE breaks off connections | 
|  | *                 if peer does not support secure renegotiation. Results | 
|  | *                 in interoperability issues with non-upgraded peers | 
|  | *                 that do not support renegotiation altogether. | 
|  | *                 (Most secure option, interoperability issues) | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param allow_legacy  Prevent or allow (SSL_NO_LEGACY_RENEGOTIATION, | 
|  | *                                        SSL_ALLOW_LEGACY_RENEGOTIATION or | 
|  | *                                        MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE) | 
|  | */ | 
|  | void mbedtls_ssl_conf_legacy_renegotiation(mbedtls_ssl_config *conf, int allow_legacy); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_RENEGOTIATION) | 
|  | /** | 
|  | * \brief          Enforce renegotiation requests. | 
|  | *                 (Default: enforced, max_records = 16) | 
|  | * | 
|  | *                 When we request a renegotiation, the peer can comply or | 
|  | *                 ignore the request. This function allows us to decide | 
|  | *                 whether to enforce our renegotiation requests by closing | 
|  | *                 the connection if the peer doesn't comply. | 
|  | * | 
|  | *                 However, records could already be in transit from the peer | 
|  | *                 when the request is emitted. In order to increase | 
|  | *                 reliability, we can accept a number of records before the | 
|  | *                 expected handshake records. | 
|  | * | 
|  | *                 The optimal value is highly dependent on the specific usage | 
|  | *                 scenario. | 
|  | * | 
|  | * \note           With DTLS and server-initiated renegotiation, the | 
|  | *                 HelloRequest is retransmitted every time mbedtls_ssl_read() times | 
|  | *                 out or receives Application Data, until: | 
|  | *                 - max_records records have beens seen, if it is >= 0, or | 
|  | *                 - the number of retransmits that would happen during an | 
|  | *                 actual handshake has been reached. | 
|  | *                 Please remember the request might be lost a few times | 
|  | *                 if you consider setting max_records to a really low value. | 
|  | * | 
|  | * \warning        On client, the grace period can only happen during | 
|  | *                 mbedtls_ssl_read(), as opposed to mbedtls_ssl_write() and mbedtls_ssl_renegotiate() | 
|  | *                 which always behave as if max_record was 0. The reason is, | 
|  | *                 if we receive application data from the server, we need a | 
|  | *                 place to write it, which only happens during mbedtls_ssl_read(). | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param max_records Use MBEDTLS_SSL_RENEGOTIATION_NOT_ENFORCED if you don't want to | 
|  | *                 enforce renegotiation, or a non-negative value to enforce | 
|  | *                 it but allow for a grace period of max_records records. | 
|  | */ | 
|  | void mbedtls_ssl_conf_renegotiation_enforced(mbedtls_ssl_config *conf, int max_records); | 
|  |  | 
|  | /** | 
|  | * \brief          Set record counter threshold for periodic renegotiation. | 
|  | *                 (Default: 2^48 - 1) | 
|  | * | 
|  | *                 Renegotiation is automatically triggered when a record | 
|  | *                 counter (outgoing or incoming) crosses the defined | 
|  | *                 threshold. The default value is meant to prevent the | 
|  | *                 connection from being closed when the counter is about to | 
|  | *                 reached its maximal value (it is not allowed to wrap). | 
|  | * | 
|  | *                 Lower values can be used to enforce policies such as "keys | 
|  | *                 must be refreshed every N packets with cipher X". | 
|  | * | 
|  | *                 The renegotiation period can be disabled by setting | 
|  | *                 conf->disable_renegotiation to | 
|  | *                 MBEDTLS_SSL_RENEGOTIATION_DISABLED. | 
|  | * | 
|  | * \note           When the configured transport is | 
|  | *                 MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation | 
|  | *                 period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM, | 
|  | *                 the maximum renegotiation period is 2^64 - 1. | 
|  | * | 
|  | * \param conf     SSL configuration | 
|  | * \param period   The threshold value: a big-endian 64-bit number. | 
|  | */ | 
|  | void mbedtls_ssl_conf_renegotiation_period(mbedtls_ssl_config *conf, | 
|  | const unsigned char period[8]); | 
|  | #endif /* MBEDTLS_SSL_RENEGOTIATION */ | 
|  |  | 
|  | /** | 
|  | * \brief          Check if there is data already read from the | 
|  | *                 underlying transport but not yet processed. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         0 if nothing's pending, 1 otherwise. | 
|  | * | 
|  | * \note           This is different in purpose and behaviour from | 
|  | *                 \c mbedtls_ssl_get_bytes_avail in that it considers | 
|  | *                 any kind of unprocessed data, not only unread | 
|  | *                 application data. If \c mbedtls_ssl_get_bytes | 
|  | *                 returns a non-zero value, this function will | 
|  | *                 also signal pending data, but the converse does | 
|  | *                 not hold. For example, in DTLS there might be | 
|  | *                 further records waiting to be processed from | 
|  | *                 the current underlying transport's datagram. | 
|  | * | 
|  | * \note           If this function returns 1 (data pending), this | 
|  | *                 does not imply that a subsequent call to | 
|  | *                 \c mbedtls_ssl_read will provide any data; | 
|  | *                 e.g., the unprocessed data might turn out | 
|  | *                 to be an alert or a handshake message. | 
|  | * | 
|  | * \note           This function is useful in the following situation: | 
|  | *                 If the SSL/TLS module successfully returns from an | 
|  | *                 operation - e.g. a handshake or an application record | 
|  | *                 read - and you're awaiting incoming data next, you | 
|  | *                 must not immediately idle on the underlying transport | 
|  | *                 to have data ready, but you need to check the value | 
|  | *                 of this function first. The reason is that the desired | 
|  | *                 data might already be read but not yet processed. | 
|  | *                 If, in contrast, a previous call to the SSL/TLS module | 
|  | *                 returned MBEDTLS_ERR_SSL_WANT_READ, it is not necessary | 
|  | *                 to call this function, as the latter error code entails | 
|  | *                 that all internal data has been processed. | 
|  | * | 
|  | */ | 
|  | int mbedtls_ssl_check_pending(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Return the number of application data bytes | 
|  | *                 remaining to be read from the current record. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         How many bytes are available in the application | 
|  | *                 data record read buffer. | 
|  | * | 
|  | * \note           When working over a datagram transport, this is | 
|  | *                 useful to detect the current datagram's boundary | 
|  | *                 in case \c mbedtls_ssl_read has written the maximal | 
|  | *                 amount of data fitting into the input buffer. | 
|  | * | 
|  | */ | 
|  | size_t mbedtls_ssl_get_bytes_avail(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Return the result of the certificate verification | 
|  | * | 
|  | * \param ssl      The SSL context to use. | 
|  | * | 
|  | * \return         \c 0 if the certificate verification was successful. | 
|  | * \return         \c -1u if the result is not available. This may happen | 
|  | *                 e.g. if the handshake aborts early, or a verification | 
|  | *                 callback returned a fatal error. | 
|  | * \return         A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX | 
|  | *                 and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h. | 
|  | */ | 
|  | uint32_t mbedtls_ssl_get_verify_result(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Return the id of the current ciphersuite | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         a ciphersuite id | 
|  | */ | 
|  | int mbedtls_ssl_get_ciphersuite_id_from_ssl(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Return the name of the current ciphersuite | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         a string containing the ciphersuite name | 
|  | */ | 
|  | const char *mbedtls_ssl_get_ciphersuite(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  |  | 
|  | /** | 
|  | * \brief          Return the (D)TLS protocol version negotiated in the | 
|  | *                 given connection. | 
|  | * | 
|  | * \note           If you call this function too early during the initial | 
|  | *                 handshake, before the two sides have agreed on a version, | 
|  | *                 this function returns #MBEDTLS_SSL_VERSION_UNKNOWN. | 
|  | * | 
|  | * \param ssl      The SSL context to query. | 
|  | * \return         The negotiated protocol version. | 
|  | */ | 
|  | static inline mbedtls_ssl_protocol_version mbedtls_ssl_get_version_number( | 
|  | const mbedtls_ssl_context *ssl) | 
|  | { | 
|  | return ssl->MBEDTLS_PRIVATE(tls_version); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief          Return the current TLS version | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         a string containing the TLS version | 
|  | */ | 
|  | const char *mbedtls_ssl_get_version(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Return the (maximum) number of bytes added by the record | 
|  | *                 layer: header + encryption/MAC overhead (inc. padding) | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         Current maximum record expansion in bytes | 
|  | */ | 
|  | int mbedtls_ssl_get_record_expansion(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Return the current maximum outgoing record payload in bytes. | 
|  | * | 
|  | * \note           The logic to determine the maximum outgoing record payload is | 
|  | *                 version-specific. It takes into account various factors, such as | 
|  | *                 the mbedtls_config.h setting \c MBEDTLS_SSL_OUT_CONTENT_LEN, extensions | 
|  | *                 such as the max fragment length or record size limit extension if | 
|  | *                 used, and for DTLS the path MTU as configured and current | 
|  | *                 record expansion. | 
|  | * | 
|  | * \note           With DTLS, \c mbedtls_ssl_write() will return an error if | 
|  | *                 called with a larger length value. | 
|  | *                 With TLS, \c mbedtls_ssl_write() will fragment the input if | 
|  | *                 necessary and return the number of bytes written; it is up | 
|  | *                 to the caller to call \c mbedtls_ssl_write() again in | 
|  | *                 order to send the remaining bytes if any. | 
|  | * | 
|  | * \sa             mbedtls_ssl_get_max_out_record_payload() | 
|  | * \sa             mbedtls_ssl_get_record_expansion() | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         Current maximum payload for an outgoing record, | 
|  | *                 or a negative error code. | 
|  | */ | 
|  | int mbedtls_ssl_get_max_out_record_payload(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          Return the current maximum incoming record payload in bytes. | 
|  | * | 
|  | * \note           The logic to determine the maximum incoming record payload is | 
|  | *                 version-specific. It takes into account various factors, such as | 
|  | *                 the mbedtls_config.h setting \c MBEDTLS_SSL_IN_CONTENT_LEN, extensions | 
|  | *                 such as the max fragment length extension or record size limit | 
|  | *                 extension if used, and the current record expansion. | 
|  | * | 
|  | * \sa             mbedtls_ssl_set_mtu() | 
|  | * \sa             mbedtls_ssl_get_max_in_record_payload() | 
|  | * \sa             mbedtls_ssl_get_record_expansion() | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         Current maximum payload for an incoming record, | 
|  | *                 or a negative error code. | 
|  | */ | 
|  | int mbedtls_ssl_get_max_in_record_payload(const mbedtls_ssl_context *ssl); | 
|  |  | 
|  | #if defined(MBEDTLS_X509_CRT_PARSE_C) | 
|  | /** | 
|  | * \brief          Return the peer certificate from the current connection. | 
|  | * | 
|  | * \param  ssl     The SSL context to use. This must be initialized and setup. | 
|  | * | 
|  | * \return         The current peer certificate, if available. | 
|  | *                 The returned certificate is owned by the SSL context and | 
|  | *                 is valid only until the next call to the SSL API. | 
|  | * \return         \c NULL if no peer certificate is available. This might | 
|  | *                 be because the chosen ciphersuite doesn't use CRTs | 
|  | *                 (PSK-based ciphersuites, for example), or because | 
|  | *                 #MBEDTLS_SSL_KEEP_PEER_CERTIFICATE has been disabled, | 
|  | *                 allowing the stack to free the peer's CRT to save memory. | 
|  | * | 
|  | * \note           For one-time inspection of the peer's certificate during | 
|  | *                 the handshake, consider registering an X.509 CRT verification | 
|  | *                 callback through mbedtls_ssl_conf_verify() instead of calling | 
|  | *                 this function. Using mbedtls_ssl_conf_verify() also comes at | 
|  | *                 the benefit of allowing you to influence the verification | 
|  | *                 process, for example by masking expected and tolerated | 
|  | *                 verification failures. | 
|  | * | 
|  | * \warning        You must not use the pointer returned by this function | 
|  | *                 after any further call to the SSL API, including | 
|  | *                 mbedtls_ssl_read() and mbedtls_ssl_write(); this is | 
|  | *                 because the pointer might change during renegotiation, | 
|  | *                 which happens transparently to the user. | 
|  | *                 If you want to use the certificate across API calls, | 
|  | *                 you must make a copy. | 
|  | */ | 
|  | const mbedtls_x509_crt *mbedtls_ssl_get_peer_cert(const mbedtls_ssl_context *ssl); | 
|  | #endif /* MBEDTLS_X509_CRT_PARSE_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_CLI_C) | 
|  | /** | 
|  | * \brief          Export a session in order to resume it later. | 
|  | * | 
|  | * \param ssl      The SSL context representing the connection for which to | 
|  | *                 to export a session structure for later resumption. | 
|  | * \param session  The target structure in which to store the exported session. | 
|  | *                 This must have been initialized with mbedtls_ssl_init_session() | 
|  | *                 but otherwise be unused. | 
|  | * | 
|  | * \note           This function can handle a variety of mechanisms for session | 
|  | *                 resumption: For TLS 1.2, both session ID-based resumption and | 
|  | *                 ticket-based resumption will be considered. For TLS 1.3, | 
|  | *                 once implemented, sessions equate to tickets, and calling | 
|  | *                 this function multiple times will export the available | 
|  | *                 tickets one a time until no further tickets are available, | 
|  | *                 in which case MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE will | 
|  | *                 be returned. | 
|  | * | 
|  | * \note           Calling this function multiple times will only be useful | 
|  | *                 once TLS 1.3 is supported. For TLS 1.2 connections, this | 
|  | *                 function should be called at most once. | 
|  | * | 
|  | * \return         \c 0 if successful. In this case, \p session can be used for | 
|  | *                 session resumption by passing it to mbedtls_ssl_set_session(), | 
|  | *                 and serialized for storage via mbedtls_ssl_session_save(). | 
|  | * \return         #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if no further session | 
|  | *                 is available for export. | 
|  | *                 This error is a non-fatal, and has no observable effect on | 
|  | *                 the SSL context or the destination session. | 
|  | * \return         Another negative error code on other kinds of failure. | 
|  | * | 
|  | * \sa             mbedtls_ssl_set_session() | 
|  | * \sa             mbedtls_ssl_session_save() | 
|  | */ | 
|  | int mbedtls_ssl_get_session(const mbedtls_ssl_context *ssl, | 
|  | mbedtls_ssl_session *session); | 
|  | #endif /* MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | /** | 
|  | * \brief          Perform the SSL handshake | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE | 
|  | *                 if the handshake is incomplete and waiting for data to | 
|  | *                 be available for reading from or writing to the underlying | 
|  | *                 transport - in this case you must call this function again | 
|  | *                 when the underlying transport is ready for the operation. | 
|  | * \return         #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous | 
|  | *                 operation is in progress (see | 
|  | *                 mbedtls_ssl_conf_async_private_cb()) - in this case you | 
|  | *                 must call this function again when the operation is ready. | 
|  | * \return         #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic | 
|  | *                 operation is in progress (see mbedtls_ecp_set_max_ops()) - | 
|  | *                 in this case you must call this function again to complete | 
|  | *                 the handshake when you're done attending other tasks. | 
|  | * \return         #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED if DTLS is in use | 
|  | *                 and the client did not demonstrate reachability yet - in | 
|  | *                 this case you must stop using the context (see below). | 
|  | * \return         Another SSL error code - in this case you must stop using | 
|  | *                 the context (see below). | 
|  | * | 
|  | * \warning        If this function returns something other than | 
|  | *                 \c 0, | 
|  | *                 #MBEDTLS_ERR_SSL_WANT_READ, | 
|  | *                 #MBEDTLS_ERR_SSL_WANT_WRITE, | 
|  | *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or | 
|  | *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, | 
|  | *                 you must stop using the SSL context for reading or writing, | 
|  | *                 and either free it or call \c mbedtls_ssl_session_reset() | 
|  | *                 on it before re-using it for a new connection; the current | 
|  | *                 connection must be closed. | 
|  | * | 
|  | * \note           If DTLS is in use, then you may choose to handle | 
|  | *                 #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging | 
|  | *                 purposes, as it is an expected return value rather than an | 
|  | *                 actual error, but you still need to reset/free the context. | 
|  | * | 
|  | * \note           Remarks regarding event-driven DTLS: | 
|  | *                 If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram | 
|  | *                 from the underlying transport layer is currently being processed, | 
|  | *                 and it is safe to idle until the timer or the underlying transport | 
|  | *                 signal a new event. This is not true for a successful handshake, | 
|  | *                 in which case the datagram of the underlying transport that is | 
|  | *                 currently being processed might or might not contain further | 
|  | *                 DTLS records. | 
|  | * | 
|  | * \note           If the context is configured to allow TLS 1.3, or if | 
|  | *                 #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto | 
|  | *                 subsystem must have been initialized by calling | 
|  | *                 psa_crypto_init() before calling this function. | 
|  | */ | 
|  | int mbedtls_ssl_handshake(mbedtls_ssl_context *ssl); | 
|  |  | 
|  | /** | 
|  | * \brief          After calling mbedtls_ssl_handshake() to start the SSL | 
|  | *                 handshake you can call this function to check whether the | 
|  | *                 handshake is over for a given SSL context. This function | 
|  | *                 should be also used to determine when to stop calling | 
|  | *                 mbedtls_handshake_step() for that context. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         \c 1 if handshake is over, \c 0 if it is still ongoing. | 
|  | */ | 
|  | static inline int mbedtls_ssl_is_handshake_over(mbedtls_ssl_context *ssl) | 
|  | { | 
|  | return ssl->MBEDTLS_PRIVATE(state) >= MBEDTLS_SSL_HANDSHAKE_OVER; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief          Perform a single step of the SSL handshake | 
|  | * | 
|  | * \note           The state of the context (ssl->state) will be at | 
|  | *                 the next state after this function returns \c 0. Do not | 
|  | *                 call this function if mbedtls_ssl_is_handshake_over() | 
|  | *                 returns \c 1. | 
|  | * | 
|  | * \warning        Whilst in the past you may have used direct access to the | 
|  | *                 context state (ssl->state) in order to ascertain when to | 
|  | *                 stop calling this function and although you can still do | 
|  | *                 so with something like ssl->MBEDTLS_PRIVATE(state) or by | 
|  | *                 defining MBEDTLS_ALLOW_PRIVATE_ACCESS, this is now | 
|  | *                 considered deprecated and could be broken in any future | 
|  | *                 release. If you still find you have good reason for such | 
|  | *                 direct access, then please do contact the team to explain | 
|  | *                 this (raise an issue or post to the mailing list), so that | 
|  | *                 we can add a solution to your problem that will be | 
|  | *                 guaranteed to work in the future. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         See mbedtls_ssl_handshake(). | 
|  | * | 
|  | * \warning        If this function returns something other than \c 0, | 
|  | *                 #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE, | 
|  | *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or | 
|  | *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using | 
|  | *                 the SSL context for reading or writing, and either free it | 
|  | *                 or call \c mbedtls_ssl_session_reset() on it before | 
|  | *                 re-using it for a new connection; the current connection | 
|  | *                 must be closed. | 
|  | */ | 
|  | int mbedtls_ssl_handshake_step(mbedtls_ssl_context *ssl); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_RENEGOTIATION) | 
|  | /** | 
|  | * \brief          Initiate an SSL renegotiation on the running connection. | 
|  | *                 Client: perform the renegotiation right now. | 
|  | *                 Server: request renegotiation, which will be performed | 
|  | *                 during the next call to mbedtls_ssl_read() if honored by | 
|  | *                 client. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return         0 if successful, or any mbedtls_ssl_handshake() return | 
|  | *                 value except #MBEDTLS_ERR_SSL_CLIENT_RECONNECT that can't | 
|  | *                 happen during a renegotiation. | 
|  | * | 
|  | * \warning        If this function returns something other than \c 0, | 
|  | *                 #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE, | 
|  | *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or | 
|  | *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using | 
|  | *                 the SSL context for reading or writing, and either free it | 
|  | *                 or call \c mbedtls_ssl_session_reset() on it before | 
|  | *                 re-using it for a new connection; the current connection | 
|  | *                 must be closed. | 
|  | * | 
|  | */ | 
|  | int mbedtls_ssl_renegotiate(mbedtls_ssl_context *ssl); | 
|  | #endif /* MBEDTLS_SSL_RENEGOTIATION */ | 
|  |  | 
|  | /** | 
|  | * \brief          Read at most 'len' application data bytes | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param buf      buffer that will hold the data | 
|  | * \param len      maximum number of bytes to read | 
|  | * | 
|  | * \return         The (positive) number of bytes read if successful. | 
|  | * \return         \c 0 if the read end of the underlying transport was closed | 
|  | *                 without sending a CloseNotify beforehand, which might happen | 
|  | *                 because of various reasons (internal error of an underlying | 
|  | *                 stack, non-conformant peer not sending a CloseNotify and | 
|  | *                 such) - in this case you must stop using the context | 
|  | *                 (see below). | 
|  | * \return         #MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY if the underlying | 
|  | *                 transport is still functional, but the peer has | 
|  | *                 acknowledged to not send anything anymore. | 
|  | * \return         #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE | 
|  | *                 if the handshake is incomplete and waiting for data to | 
|  | *                 be available for reading from or writing to the underlying | 
|  | *                 transport - in this case you must call this function again | 
|  | *                 when the underlying transport is ready for the operation. | 
|  | * \return         #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous | 
|  | *                 operation is in progress (see | 
|  | *                 mbedtls_ssl_conf_async_private_cb()) - in this case you | 
|  | *                 must call this function again when the operation is ready. | 
|  | * \return         #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic | 
|  | *                 operation is in progress (see mbedtls_ecp_set_max_ops()) - | 
|  | *                 in this case you must call this function again to complete | 
|  | *                 the handshake when you're done attending other tasks. | 
|  | * \return         #MBEDTLS_ERR_SSL_CLIENT_RECONNECT if we're at the server | 
|  | *                 side of a DTLS connection and the client is initiating a | 
|  | *                 new connection using the same source port. See below. | 
|  | * \return         Another SSL error code - in this case you must stop using | 
|  | *                 the context (see below). | 
|  | * | 
|  | * \warning        If this function returns something other than | 
|  | *                 a positive value, | 
|  | *                 #MBEDTLS_ERR_SSL_WANT_READ, | 
|  | *                 #MBEDTLS_ERR_SSL_WANT_WRITE, | 
|  | *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, | 
|  | *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or | 
|  | *                 #MBEDTLS_ERR_SSL_CLIENT_RECONNECT, | 
|  | *                 you must stop using the SSL context for reading or writing, | 
|  | *                 and either free it or call \c mbedtls_ssl_session_reset() | 
|  | *                 on it before re-using it for a new connection; the current | 
|  | *                 connection must be closed. | 
|  | * | 
|  | * \note           When this function returns #MBEDTLS_ERR_SSL_CLIENT_RECONNECT | 
|  | *                 (which can only happen server-side), it means that a client | 
|  | *                 is initiating a new connection using the same source port. | 
|  | *                 You can either treat that as a connection close and wait | 
|  | *                 for the client to resend a ClientHello, or directly | 
|  | *                 continue with \c mbedtls_ssl_handshake() with the same | 
|  | *                 context (as it has been reset internally). Either way, you | 
|  | *                 must make sure this is seen by the application as a new | 
|  | *                 connection: application state, if any, should be reset, and | 
|  | *                 most importantly the identity of the client must be checked | 
|  | *                 again. WARNING: not validating the identity of the client | 
|  | *                 again, or not transmitting the new identity to the | 
|  | *                 application layer, would allow authentication bypass! | 
|  | * | 
|  | * \note           Remarks regarding event-driven DTLS: | 
|  | *                 - If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram | 
|  | *                   from the underlying transport layer is currently being processed, | 
|  | *                   and it is safe to idle until the timer or the underlying transport | 
|  | *                   signal a new event. | 
|  | *                 - This function may return MBEDTLS_ERR_SSL_WANT_READ even if data was | 
|  | *                   initially available on the underlying transport, as this data may have | 
|  | *                   been only e.g. duplicated messages or a renegotiation request. | 
|  | *                   Therefore, you must be prepared to receive MBEDTLS_ERR_SSL_WANT_READ even | 
|  | *                   when reacting to an incoming-data event from the underlying transport. | 
|  | *                 - On success, the datagram of the underlying transport that is currently | 
|  | *                   being processed may contain further DTLS records. You should call | 
|  | *                   \c mbedtls_ssl_check_pending to check for remaining records. | 
|  | * | 
|  | */ | 
|  | int mbedtls_ssl_read(mbedtls_ssl_context *ssl, unsigned char *buf, size_t len); | 
|  |  | 
|  | /** | 
|  | * \brief          Try to write exactly 'len' application data bytes | 
|  | * | 
|  | * \warning        This function will do partial writes in some cases. If the | 
|  | *                 return value is non-negative but less than length, the | 
|  | *                 function must be called again with updated arguments: | 
|  | *                 buf + ret, len - ret (if ret is the return value) until | 
|  | *                 it returns a value equal to the last 'len' argument. | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param buf      buffer holding the data | 
|  | * \param len      how many bytes must be written | 
|  | * | 
|  | * \return         The (non-negative) number of bytes actually written if | 
|  | *                 successful (may be less than \p len). | 
|  | * \return         #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE | 
|  | *                 if the handshake is incomplete and waiting for data to | 
|  | *                 be available for reading from or writing to the underlying | 
|  | *                 transport - in this case you must call this function again | 
|  | *                 when the underlying transport is ready for the operation. | 
|  | * \return         #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous | 
|  | *                 operation is in progress (see | 
|  | *                 mbedtls_ssl_conf_async_private_cb()) - in this case you | 
|  | *                 must call this function again when the operation is ready. | 
|  | * \return         #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic | 
|  | *                 operation is in progress (see mbedtls_ecp_set_max_ops()) - | 
|  | *                 in this case you must call this function again to complete | 
|  | *                 the handshake when you're done attending other tasks. | 
|  | * \return         Another SSL error code - in this case you must stop using | 
|  | *                 the context (see below). | 
|  | * | 
|  | * \warning        If this function returns something other than | 
|  | *                 a non-negative value, | 
|  | *                 #MBEDTLS_ERR_SSL_WANT_READ, | 
|  | *                 #MBEDTLS_ERR_SSL_WANT_WRITE, | 
|  | *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or | 
|  | *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, | 
|  | *                 you must stop using the SSL context for reading or writing, | 
|  | *                 and either free it or call \c mbedtls_ssl_session_reset() | 
|  | *                 on it before re-using it for a new connection; the current | 
|  | *                 connection must be closed. | 
|  | * | 
|  | * \note           When this function returns #MBEDTLS_ERR_SSL_WANT_WRITE/READ, | 
|  | *                 it must be called later with the *same* arguments, | 
|  | *                 until it returns a value greater than or equal to 0. When | 
|  | *                 the function returns #MBEDTLS_ERR_SSL_WANT_WRITE there may be | 
|  | *                 some partial data in the output buffer, however this is not | 
|  | *                 yet sent. | 
|  | * | 
|  | * \note           If the requested length is greater than the maximum | 
|  | *                 fragment length (either the built-in limit or the one set | 
|  | *                 or negotiated with the peer), then: | 
|  | *                 - with TLS, less bytes than requested are written. | 
|  | *                 - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned. | 
|  | *                 \c mbedtls_ssl_get_max_out_record_payload() may be used to | 
|  | *                 query the active maximum fragment length. | 
|  | * | 
|  | * \note           Attempting to write 0 bytes will result in an empty TLS | 
|  | *                 application record being sent. | 
|  | */ | 
|  | int mbedtls_ssl_write(mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len); | 
|  |  | 
|  | /** | 
|  | * \brief           Send an alert message | 
|  | * | 
|  | * \param ssl       SSL context | 
|  | * \param level     The alert level of the message | 
|  | *                  (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL) | 
|  | * \param message   The alert message (SSL_ALERT_MSG_*) | 
|  | * | 
|  | * \return          0 if successful, or a specific SSL error code. | 
|  | * | 
|  | * \note           If this function returns something other than 0 or | 
|  | *                 MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using | 
|  | *                 the SSL context for reading or writing, and either free it or | 
|  | *                 call \c mbedtls_ssl_session_reset() on it before re-using it | 
|  | *                 for a new connection; the current connection must be closed. | 
|  | */ | 
|  | int mbedtls_ssl_send_alert_message(mbedtls_ssl_context *ssl, | 
|  | unsigned char level, | 
|  | unsigned char message); | 
|  | /** | 
|  | * \brief          Notify the peer that the connection is being closed | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * | 
|  | * \return          0 if successful, or a specific SSL error code. | 
|  | * | 
|  | * \note           If this function returns something other than 0 or | 
|  | *                 MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using | 
|  | *                 the SSL context for reading or writing, and either free it or | 
|  | *                 call \c mbedtls_ssl_session_reset() on it before re-using it | 
|  | *                 for a new connection; the current connection must be closed. | 
|  | */ | 
|  | int mbedtls_ssl_close_notify(mbedtls_ssl_context *ssl); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_EARLY_DATA) | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_SRV_C) | 
|  | /** | 
|  | * \brief          Read at most 'len' application data bytes while performing | 
|  | *                 the handshake (early data). | 
|  | * | 
|  | * \note           This function behaves mainly as mbedtls_ssl_read(). The | 
|  | *                 specification of mbedtls_ssl_read() relevant to TLS 1.3 | 
|  | *                 (thus not the parts specific to (D)TLS 1.2) applies to this | 
|  | *                 function and the present documentation is restricted to the | 
|  | *                 differences with mbedtls_ssl_read(). | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param buf      buffer that will hold the data | 
|  | * \param len      maximum number of bytes to read | 
|  | * | 
|  | * \return         One additional specific return value: | 
|  | *                 #MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA. | 
|  | * | 
|  | *                 #MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA is returned when it | 
|  | *                 is not possible to read early data for the SSL context | 
|  | *                 \p ssl. | 
|  | * | 
|  | *                 It may have been possible and it is not possible | 
|  | *                 anymore because the server received the End of Early Data | 
|  | *                 message or the maximum number of allowed early data for the | 
|  | *                 PSK in use has been reached. | 
|  | * | 
|  | *                 It may never have been possible and will never be possible | 
|  | *                 for the SSL context \p ssl because the use of early data | 
|  | *                 is disabled for that context or more generally the context | 
|  | *                 is not suitably configured to enable early data or the | 
|  | *                 client does not use early data or the first call to the | 
|  | *                 function was done while the handshake was already too | 
|  | *                 advanced to gather and accept early data. | 
|  | * | 
|  | *                 It is not possible to read early data for the SSL context | 
|  | *                 \p ssl but this does not preclude for using it with | 
|  | *                 mbedtls_ssl_write(), mbedtls_ssl_read() or | 
|  | *                 mbedtls_ssl_handshake(). | 
|  | * | 
|  | * \note           When a server wants to retrieve early data, it is expected | 
|  | *                 that this function starts the handshake for the SSL context | 
|  | *                 \p ssl. But this is not mandatory. | 
|  | * | 
|  | */ | 
|  | int mbedtls_ssl_read_early_data(mbedtls_ssl_context *ssl, | 
|  | unsigned char *buf, size_t len); | 
|  | #endif /* MBEDTLS_SSL_SRV_C */ | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_CLI_C) | 
|  | /** | 
|  | * \brief          Try to write exactly 'len' application data bytes while | 
|  | *                 performing the handshake (early data). | 
|  | * | 
|  | * \note           This function behaves mainly as mbedtls_ssl_write(). The | 
|  | *                 specification of mbedtls_ssl_write() relevant to TLS 1.3 | 
|  | *                 (thus not the parts specific to (D)TLS1.2) applies to this | 
|  | *                 function and the present documentation is restricted to the | 
|  | *                 differences with mbedtls_ssl_write(). | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | * \param buf      buffer holding the data | 
|  | * \param len      how many bytes must be written | 
|  | * | 
|  | * \return         One additional specific return value: | 
|  | *                 #MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA. | 
|  | * | 
|  | *                 #MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA is returned when it | 
|  | *                 is not possible to write early data for the SSL context | 
|  | *                 \p ssl. | 
|  | * | 
|  | *                 It may have been possible and it is not possible | 
|  | *                 anymore because the client received the server Finished | 
|  | *                 message, the server rejected early data or the maximum | 
|  | *                 number of allowed early data for the PSK in use has been | 
|  | *                 reached. | 
|  | * | 
|  | *                 It may never have been possible and will never be possible | 
|  | *                 for the SSL context \p ssl because the use of early data | 
|  | *                 is disabled for that context or more generally the context | 
|  | *                 is not suitably configured to enable early data or the first | 
|  | *                 call to the function was done while the handshake was | 
|  | *                 already completed. | 
|  | * | 
|  | *                 It is not possible to write early data for the SSL context | 
|  | *                 \p ssl but this does not preclude for using it with | 
|  | *                 mbedtls_ssl_write(), mbedtls_ssl_read() or | 
|  | *                 mbedtls_ssl_handshake(). | 
|  | * | 
|  | * \note           This function may write early data only if the SSL context | 
|  | *                 has been configured for the handshake with a PSK for which | 
|  | *                 early data is allowed. | 
|  | * | 
|  | * \note           To maximize the number of early data that can be written in | 
|  | *                 the course of the handshake, it is expected that this | 
|  | *                 function starts the handshake for the SSL context \p ssl. | 
|  | *                 But this is not mandatory. | 
|  | * | 
|  | * \note           This function does not provide any information on whether | 
|  | *                 the server has accepted or will accept early data or not. | 
|  | *                 When it returns a positive value, it just means that it | 
|  | *                 has written early data to the server. To know whether the | 
|  | *                 server has accepted early data or not, you should call | 
|  | *                 mbedtls_ssl_get_early_data_status() with the handshake | 
|  | *                 completed. | 
|  | */ | 
|  | int mbedtls_ssl_write_early_data(mbedtls_ssl_context *ssl, | 
|  | const unsigned char *buf, size_t len); | 
|  |  | 
|  | #define MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT  0 | 
|  | #define MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED  1 | 
|  | #define MBEDTLS_SSL_EARLY_DATA_STATUS_REJECTED  2 | 
|  | /** | 
|  | * \brief Get the status of the negotiation of the use of early data. | 
|  | * | 
|  | * \param ssl      The SSL context to query | 
|  | * | 
|  | * \return         #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if this function is called | 
|  | *                 from the server-side. | 
|  | * | 
|  | * \return         #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if this function is called | 
|  | *                 prior to completion of the handshake. | 
|  | * | 
|  | * \return         #MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT if the client has | 
|  | *                 not indicated the use of early data to the server. | 
|  | * | 
|  | * \return         #MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED if the client has | 
|  | *                 indicated the use of early data and the server has accepted | 
|  | *                 it. | 
|  | * | 
|  | * \return         #MBEDTLS_SSL_EARLY_DATA_STATUS_REJECTED if the client has | 
|  | *                 indicated the use of early data but the server has rejected | 
|  | *                 it. In this situation, the client may want to re-send the | 
|  | *                 early data it may have tried to send by calling | 
|  | *                 mbedtls_ssl_write_early_data() as ordinary post-handshake | 
|  | *                 application data by calling mbedtls_ssl_write(). | 
|  | * | 
|  | */ | 
|  | int mbedtls_ssl_get_early_data_status(mbedtls_ssl_context *ssl); | 
|  | #endif /* MBEDTLS_SSL_CLI_C */ | 
|  |  | 
|  | #endif /* MBEDTLS_SSL_EARLY_DATA */ | 
|  |  | 
|  | /** | 
|  | * \brief          Free referenced items in an SSL context and clear memory | 
|  | * | 
|  | * \param ssl      SSL context | 
|  | */ | 
|  | void mbedtls_ssl_free(mbedtls_ssl_context *ssl); | 
|  |  | 
|  | #if defined(MBEDTLS_SSL_CONTEXT_SERIALIZATION) | 
|  | /** | 
|  | * \brief          Save an active connection as serialized data in a buffer. | 
|  | *                 This allows the freeing or re-using of the SSL context | 
|  | *                 while still picking up the connection later in a way that | 
|  | *                 it entirely transparent to the peer. | 
|  | * | 
|  | * \see            mbedtls_ssl_context_load() | 
|  | * | 
|  | * \note           The serialized data only contains the data that is | 
|  | *                 necessary to resume the connection: negotiated protocol | 
|  | *                 options, session identifier, keys, etc. | 
|  | *                 Loading a saved SSL context does not restore settings and | 
|  | *                 state related to how the application accesses the context, | 
|  | *                 such as configured callback functions, user data, pending | 
|  | *                 incoming or outgoing data, etc. | 
|  | * | 
|  | * \note           This feature is currently only available under certain | 
|  | *                 conditions, see the documentation of the return value | 
|  | *                 #MBEDTLS_ERR_SSL_BAD_INPUT_DATA for details. | 
|  | * | 
|  | * \note           When this function succeeds, it calls | 
|  | *                 mbedtls_ssl_session_reset() on \p ssl which as a result is | 
|  | *                 no longer associated with the connection that has been | 
|  | *                 serialized. This avoids creating copies of the connection | 
|  | *                 state. You're then free to either re-use the context | 
|  | *                 structure for a different connection, or call | 
|  | *                 mbedtls_ssl_free() on it. See the documentation of | 
|  | *                 mbedtls_ssl_session_reset() for more details. | 
|  | * | 
|  | * \param ssl      The SSL context to save. On success, it is no longer | 
|  | *                 associated with the connection that has been serialized. | 
|  | * \param buf      The buffer to write the serialized data to. It must be a | 
|  | *                 writeable buffer of at least \p buf_len bytes, or may be \c | 
|  | *                 NULL if \p buf_len is \c 0. | 
|  | * \param buf_len  The number of bytes available for writing in \p buf. | 
|  | * \param olen     The size in bytes of the data that has been or would have | 
|  | *                 been written. It must point to a valid \c size_t. | 
|  | * | 
|  | * \note           \p olen is updated to the correct value regardless of | 
|  | *                 whether \p buf_len was large enough. This makes it possible | 
|  | *                 to determine the necessary size by calling this function | 
|  | *                 with \p buf set to \c NULL and \p buf_len to \c 0. However, | 
|  | *                 the value of \p olen is only guaranteed to be correct when | 
|  | *                 the function returns #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL or | 
|  | *                 \c 0. If the return value is different, then the value of | 
|  | *                 \p olen is undefined. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         #MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if \p buf is too small. | 
|  | * \return         #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed | 
|  | *                 while resetting the context. | 
|  | * \return         #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if a handshake is in | 
|  | *                 progress, or there is pending data for reading or sending, | 
|  | *                 or the connection does not use DTLS 1.2 with an AEAD | 
|  | *                 ciphersuite, or renegotiation is enabled. | 
|  | */ | 
|  | int mbedtls_ssl_context_save(mbedtls_ssl_context *ssl, | 
|  | unsigned char *buf, | 
|  | size_t buf_len, | 
|  | size_t *olen); | 
|  |  | 
|  | /** | 
|  | * \brief          Load serialized connection data to an SSL context. | 
|  | * | 
|  | * \see            mbedtls_ssl_context_save() | 
|  | * | 
|  | * \warning        The same serialized data must never be loaded into more | 
|  | *                 that one context. In order to ensure that, after | 
|  | *                 successfully loading serialized data to an SSL context, you | 
|  | *                 should immediately destroy or invalidate all copies of the | 
|  | *                 serialized data that was loaded. Loading the same data in | 
|  | *                 more than one context would cause severe security failures | 
|  | *                 including but not limited to loss of confidentiality. | 
|  | * | 
|  | * \note           Before calling this function, the SSL context must be | 
|  | *                 prepared in one of the two following ways. The first way is | 
|  | *                 to take a context freshly initialised with | 
|  | *                 mbedtls_ssl_init() and call mbedtls_ssl_setup() on it with | 
|  | *                 the same ::mbedtls_ssl_config structure that was used in | 
|  | *                 the original connection. The second way is to | 
|  | *                 call mbedtls_ssl_session_reset() on a context that was | 
|  | *                 previously prepared as above but used in the meantime. | 
|  | *                 Either way, you must not use the context to perform a | 
|  | *                 handshake between calling mbedtls_ssl_setup() or | 
|  | *                 mbedtls_ssl_session_reset() and calling this function. You | 
|  | *                 may however call other setter functions in that time frame | 
|  | *                 as indicated in the note below. | 
|  | * | 
|  | * \note           Before or after calling this function successfully, you | 
|  | *                 also need to configure some connection-specific callbacks | 
|  | *                 and settings before you can use the connection again | 
|  | *                 (unless they were already set before calling | 
|  | *                 mbedtls_ssl_session_reset() and the values are suitable for | 
|  | *                 the present connection). Specifically, you want to call | 
|  | *                 at least mbedtls_ssl_set_bio(), | 
|  | *                 mbedtls_ssl_set_timer_cb(), and | 
|  | *                 mbedtls_ssl_set_user_data_n() or | 
|  | *                 mbedtls_ssl_set_user_data_p() if they were set originally. | 
|  | *                 All other SSL setter functions | 
|  | *                 are not necessary to call, either because they're only used | 
|  | *                 in handshakes, or because the setting is already saved. You | 
|  | *                 might choose to call them anyway, for example in order to | 
|  | *                 share code between the cases of establishing a new | 
|  | *                 connection and the case of loading an already-established | 
|  | *                 connection. | 
|  | * | 
|  | * \note           If you have new information about the path MTU, you want to | 
|  | *                 call mbedtls_ssl_set_mtu() after calling this function, as | 
|  | *                 otherwise this function would overwrite your | 
|  | *                 newly-configured value with the value that was active when | 
|  | *                 the context was saved. | 
|  | * | 
|  | * \note           When this function returns an error code, it calls | 
|  | *                 mbedtls_ssl_free() on \p ssl. In this case, you need to | 
|  | *                 prepare the context with the usual sequence starting with a | 
|  | *                 call to mbedtls_ssl_init() if you want to use it again. | 
|  | * | 
|  | * \param ssl      The SSL context structure to be populated. It must have | 
|  | *                 been prepared as described in the note above. | 
|  | * \param buf      The buffer holding the serialized connection data. It must | 
|  | *                 be a readable buffer of at least \p len bytes. | 
|  | * \param len      The size of the serialized data in bytes. | 
|  | * | 
|  | * \return         \c 0 if successful. | 
|  | * \return         #MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed. | 
|  | * \return         #MBEDTLS_ERR_SSL_VERSION_MISMATCH if the serialized data | 
|  | *                 comes from a different Mbed TLS version or build. | 
|  | * \return         #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid. | 
|  | */ | 
|  | int mbedtls_ssl_context_load(mbedtls_ssl_context *ssl, | 
|  | const unsigned char *buf, | 
|  | size_t len); | 
|  | #endif /* MBEDTLS_SSL_CONTEXT_SERIALIZATION */ | 
|  |  | 
|  | /** | 
|  | * \brief          Initialize an SSL configuration context | 
|  | *                 Just makes the context ready for | 
|  | *                 mbedtls_ssl_config_defaults() or mbedtls_ssl_config_free(). | 
|  | * | 
|  | * \note           You need to call mbedtls_ssl_config_defaults() unless you | 
|  | *                 manually set all of the relevant fields yourself. | 
|  | * | 
|  | * \param conf     SSL configuration context | 
|  | */ | 
|  | void mbedtls_ssl_config_init(mbedtls_ssl_config *conf); | 
|  |  | 
|  | /** | 
|  | * \brief          Load reasonable default SSL configuration values. | 
|  | *                 (You need to call mbedtls_ssl_config_init() first.) | 
|  | * | 
|  | * \param conf     SSL configuration context | 
|  | * \param endpoint MBEDTLS_SSL_IS_CLIENT or MBEDTLS_SSL_IS_SERVER | 
|  | * \param transport MBEDTLS_SSL_TRANSPORT_STREAM for TLS, or | 
|  | *                  MBEDTLS_SSL_TRANSPORT_DATAGRAM for DTLS | 
|  | * \param preset   a MBEDTLS_SSL_PRESET_XXX value | 
|  | * | 
|  | * \note           See \c mbedtls_ssl_conf_transport() for notes on DTLS. | 
|  | * | 
|  | * \return         0 if successful, or | 
|  | *                 MBEDTLS_ERR_XXX_ALLOC_FAILED on memory allocation error. | 
|  | */ | 
|  | int mbedtls_ssl_config_defaults(mbedtls_ssl_config *conf, | 
|  | int endpoint, int transport, int preset); | 
|  |  | 
|  | /** | 
|  | * \brief          Free an SSL configuration context | 
|  | * | 
|  | * \param conf     SSL configuration context | 
|  | */ | 
|  | void mbedtls_ssl_config_free(mbedtls_ssl_config *conf); | 
|  |  | 
|  | /** | 
|  | * \brief          Initialize SSL session structure | 
|  | * | 
|  | * \param session  SSL session | 
|  | */ | 
|  | void mbedtls_ssl_session_init(mbedtls_ssl_session *session); | 
|  |  | 
|  | /** | 
|  | * \brief          Free referenced items in an SSL session including the | 
|  | *                 peer certificate and clear memory | 
|  | * | 
|  | * \note           A session object can be freed even if the SSL context | 
|  | *                 that was used to retrieve the session is still in use. | 
|  | * | 
|  | * \param session  SSL session | 
|  | */ | 
|  | void mbedtls_ssl_session_free(mbedtls_ssl_session *session); | 
|  |  | 
|  | /** | 
|  | * \brief          TLS-PRF function for key derivation. | 
|  | * | 
|  | * \param prf      The tls_prf type function type to be used. | 
|  | * \param secret   Secret for the key derivation function. | 
|  | * \param slen     Length of the secret. | 
|  | * \param label    String label for the key derivation function, | 
|  | *                 terminated with null character. | 
|  | * \param random   Random bytes. | 
|  | * \param rlen     Length of the random bytes buffer. | 
|  | * \param dstbuf   The buffer holding the derived key. | 
|  | * \param dlen     Length of the output buffer. | 
|  | * | 
|  | * \return         0 on success. An SSL specific error on failure. | 
|  | */ | 
|  | int  mbedtls_ssl_tls_prf(const mbedtls_tls_prf_types prf, | 
|  | const unsigned char *secret, size_t slen, | 
|  | const char *label, | 
|  | const unsigned char *random, size_t rlen, | 
|  | unsigned char *dstbuf, size_t dlen); | 
|  |  | 
|  | #ifdef __cplusplus | 
|  | } | 
|  | #endif | 
|  |  | 
|  | #endif /* ssl.h */ |