Willie Solano
mbed TLS Build
Diff: include/mbedtls/ssl.h
- Revision:
- 0:cdf462088d13
diff -r 000000000000 -r cdf462088d13 include/mbedtls/ssl.h
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/include/mbedtls/ssl.h Thu Jan 05 00:18:44 2017 +0000
@@ -0,0 +1,2551 @@
+/**
+ * \file ssl.h
+ *
+ * \brief SSL/TLS functions.
+ *
+ * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ * 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.
+ *
+ * This file is part of mbed TLS (https://tls.mbed.org)
+ */
+#ifndef MBEDTLS_SSL_H
+#define MBEDTLS_SSL_H
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#include "bignum.h"
+#include "ecp.h"
+
+#include "ssl_ciphersuites.h"
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+#include "x509_crt.h"
+#include "x509_crl.h"
+#endif
+
+#if defined(MBEDTLS_DHM_C)
+#include "dhm.h"
+#endif
+
+#if defined(MBEDTLS_ECDH_C)
+#include "ecdh.h"
+#endif
+
+#if defined(MBEDTLS_ZLIB_SUPPORT)
+#include "zlib.h"
+#endif
+
+#if defined(MBEDTLS_HAVE_TIME)
+#include "mbedtls/platform_time.h"
+#endif
+
+/*
+ * SSL Error codes
+ */
+#define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE -0x7080 /**< The requested feature is not available. */
+#define MBEDTLS_ERR_SSL_BAD_INPUT_DATA -0x7100 /**< Bad input parameters to function. */
+#define MBEDTLS_ERR_SSL_INVALID_MAC -0x7180 /**< Verification of the message MAC failed. */
+#define MBEDTLS_ERR_SSL_INVALID_RECORD -0x7200 /**< An invalid SSL record was received. */
+#define MBEDTLS_ERR_SSL_CONN_EOF -0x7280 /**< The connection indicated an EOF. */
+#define MBEDTLS_ERR_SSL_UNKNOWN_CIPHER -0x7300 /**< An unknown cipher was received. */
+#define MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN -0x7380 /**< The server has no ciphersuites in common with the client. */
+#define MBEDTLS_ERR_SSL_NO_RNG -0x7400 /**< No RNG was provided to the SSL module. */
+#define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE -0x7480 /**< No client certification received from the client, but required by the authentication mode. */
+#define MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE -0x7500 /**< Our own certificate(s) is/are too large to send in an SSL message. */
+#define MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED -0x7580 /**< The own certificate is not set, but needed by the server. */
+#define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED -0x7600 /**< The own private key or pre-shared key is not set, but needed. */
+#define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED -0x7680 /**< No CA Chain is set, but required to operate. */
+#define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE -0x7700 /**< An unexpected message was received from our peer. */
+#define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE -0x7780 /**< A fatal alert message was received from our peer. */
+#define MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED -0x7800 /**< Verification of our peer failed. */
+#define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY -0x7880 /**< The peer notified us that the connection is going to be closed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO -0x7900 /**< Processing of the ClientHello handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO -0x7980 /**< Processing of the ServerHello handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE -0x7A00 /**< Processing of the Certificate handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST -0x7A80 /**< Processing of the CertificateRequest handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE -0x7B00 /**< Processing of the ServerKeyExchange handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE -0x7B80 /**< Processing of the ServerHelloDone handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE -0x7C00 /**< Processing of the ClientKeyExchange handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP -0x7C80 /**< Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Read Public. */
+#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_CS -0x7D00 /**< Processing of the ClientKeyExchange handshake message failed in DHM / ECDH Calculate Secret. */
+#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY -0x7D80 /**< Processing of the CertificateVerify handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC -0x7E00 /**< Processing of the ChangeCipherSpec handshake message failed. */
+#define MBEDTLS_ERR_SSL_BAD_HS_FINISHED -0x7E80 /**< Processing of the Finished handshake message failed. */
+#define MBEDTLS_ERR_SSL_ALLOC_FAILED -0x7F00 /**< Memory allocation failed */
+#define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED -0x7F80 /**< Hardware acceleration function returned with error */
+#define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH -0x6F80 /**< Hardware acceleration function skipped / left alone data */
+#define MBEDTLS_ERR_SSL_COMPRESSION_FAILED -0x6F00 /**< Processing of the compression / decompression failed */
+#define MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION -0x6E80 /**< Handshake protocol not within min/max boundaries */
+#define MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET -0x6E00 /**< Processing of the NewSessionTicket handshake message failed. */
+#define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED -0x6D80 /**< Session ticket has expired. */
+#define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH -0x6D00 /**< Public key type mismatch (eg, asked for RSA key exchange and presented EC key) */
+#define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY -0x6C80 /**< Unknown identity received (eg, PSK identity) */
+#define MBEDTLS_ERR_SSL_INTERNAL_ERROR -0x6C00 /**< Internal error (eg, unexpected failure in lower-level module) */
+#define MBEDTLS_ERR_SSL_COUNTER_WRAPPING -0x6B80 /**< A counter would wrap (eg, too many messages exchanged). */
+#define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO -0x6B00 /**< Unexpected message at ServerHello in renegotiation. */
+#define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED -0x6A80 /**< DTLS client must retry for hello verification */
+#define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL -0x6A00 /**< A buffer is too small to receive or write a message */
+#define MBEDTLS_ERR_SSL_NO_USABLE_CIPHERSUITE -0x6980 /**< None of the common ciphersuites is usable (eg, no suitable certificate, see debug messages). */
+#define MBEDTLS_ERR_SSL_WANT_READ -0x6900 /**< Connection requires a read call. */
+#define MBEDTLS_ERR_SSL_WANT_WRITE -0x6880 /**< Connection requires a write call. */
+#define MBEDTLS_ERR_SSL_TIMEOUT -0x6800 /**< The operation timed out. */
+#define MBEDTLS_ERR_SSL_CLIENT_RECONNECT -0x6780 /**< The client initiated a reconnect from the same port. */
+#define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD -0x6700 /**< Record header looks valid but is not expected. */
+#define MBEDTLS_ERR_SSL_NON_FATAL -0x6680 /**< The alert message received indicates a non-fatal error. */
+#define MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH -0x6600 /**< Couldn't set the hash for verifying CertificateVerify */
+
+/*
+ * Various constants
+ */
+#define MBEDTLS_SSL_MAJOR_VERSION_3 3
+#define MBEDTLS_SSL_MINOR_VERSION_0 0 /*!< SSL v3.0 */
+#define MBEDTLS_SSL_MINOR_VERSION_1 1 /*!< TLS v1.0 */
+#define MBEDTLS_SSL_MINOR_VERSION_2 2 /*!< TLS v1.1 */
+#define MBEDTLS_SSL_MINOR_VERSION_3 3 /*!< TLS v1.2 */
+
+#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 */
+
+/* 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_IS_NOT_FALLBACK 0
+#define MBEDTLS_SSL_IS_FALLBACK 1
+
+#define MBEDTLS_SSL_EXTENDED_MS_DISABLED 0
+#define MBEDTLS_SSL_EXTENDED_MS_ENABLED 1
+
+#define MBEDTLS_SSL_ETM_DISABLED 0
+#define MBEDTLS_SSL_ETM_ENABLED 1
+
+#define MBEDTLS_SSL_COMPRESS_NULL 0
+#define MBEDTLS_SSL_COMPRESS_DEFLATE 1
+
+#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_CBC_RECORD_SPLITTING_DISABLED 0
+#define MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED 1
+
+#define MBEDTLS_SSL_ARC4_ENABLED 0
+#define MBEDTLS_SSL_ARC4_DISABLED 1
+
+#define MBEDTLS_SSL_PRESET_DEFAULT 0
+#define MBEDTLS_SSL_PRESET_SUITEB 2
+
+/*
+ * 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 config.h or define them on the compiler command line.
+ * \{
+ */
+
+#if !defined(MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME)
+#define MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME 86400 /**< Lifetime of session tickets (if enabled) */
+#endif
+
+/*
+ * Maxium 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_MAX_CONTENT_LEN)
+#define MBEDTLS_SSL_MAX_CONTENT_LEN 16384 /**< Size of the input / output buffer */
+#endif
+
+/* \} name SECTION: Module settings */
+
+/*
+ * Length of the verify data for secure renegotiation
+ */
+#if defined(MBEDTLS_SSL_PROTO_SSL3)
+#define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 36
+#else
+#define MBEDTLS_SSL_VERIFY_DATA_MAX_LEN 12
+#endif
+
+/*
+ * Signaling ciphersuite values (SCSV)
+ */
+#define MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO 0xFF /**< renegotiation info ext */
+#define MBEDTLS_SSL_FALLBACK_SCSV_VALUE 0x5600 /**< RFC 7507 section 2 */
+
+/*
+ * 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
+
+/*
+ * 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_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_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_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_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
+
+/*
+ * 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_SUPPORTED_ELLIPTIC_CURVES 10
+#define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS 11
+
+#define MBEDTLS_TLS_EXT_SIG_ALG 13
+
+#define MBEDTLS_TLS_EXT_ALPN 16
+
+#define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC 22 /* 0x16 */
+#define MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET 0x0017 /* 23 */
+
+#define MBEDTLS_TLS_EXT_SESSION_TICKET 35
+
+#define MBEDTLS_TLS_EXT_ECJPAKE_KKPP 256 /* experimental */
+
+#define MBEDTLS_TLS_EXT_RENEGOTIATION_INFO 0xFF01
+
+/*
+ * Size defines
+ */
+#if !defined(MBEDTLS_PSK_MAX_LEN)
+#define MBEDTLS_PSK_MAX_LEN 32 /* 256 bits */
+#endif
+
+/* 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 )
+
+#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_HANDSHAKE_OVER,
+ MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET,
+ MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT,
+}
+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
+ *
+ * \return The callback must return the number of bytes received,
+ * or a non-zero error code.
+ * If performing non-blocking I/O, \c MBEDTLS_ERR_SSL_WANT_READ
+ * must be returned when the operation would block.
+ *
+ * \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 nomber of millisecondes 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 a 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 ssl_internal.h */
+typedef struct mbedtls_ssl_transform mbedtls_ssl_transform;
+typedef struct mbedtls_ssl_handshake_params mbedtls_ssl_handshake_params;
+#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
+
+/*
+ * This structure is used for storing current session data.
+ */
+struct mbedtls_ssl_session
+{
+#if defined(MBEDTLS_HAVE_TIME)
+ mbedtls_time_t start; /*!< starting time */
+#endif
+ int ciphersuite; /*!< chosen ciphersuite */
+ int compression; /*!< chosen compression */
+ size_t id_len; /*!< session id length */
+ unsigned char id[32]; /*!< session identifier */
+ unsigned char master[48]; /*!< the master secret */
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+ mbedtls_x509_crt *peer_cert; /*!< peer X.509 cert chain */
+#endif /* MBEDTLS_X509_CRT_PARSE_C */
+ uint32_t verify_result; /*!< verification result */
+
+#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
+ unsigned char *ticket; /*!< RFC 5077 session ticket */
+ size_t ticket_len; /*!< session ticket length */
+ uint32_t ticket_lifetime; /*!< ticket lifetime hint */
+#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */
+
+#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
+ unsigned char mfl_code; /*!< MaxFragmentLength negotiated by peer */
+#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
+
+#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
+ int trunc_hmac; /*!< flag for truncated hmac activation */
+#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
+
+#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
+ int encrypt_then_mac; /*!< flag for EtM activation */
+#endif
+};
+
+/**
+ * SSL/TLS configuration to be shared between mbedtls_ssl_context structures.
+ */
+struct mbedtls_ssl_config
+{
+ /* Group items by size (largest first) to minimize padding overhead */
+
+ /*
+ * Pointers
+ */
+
+ const int *ciphersuite_list[4]; /*!< allowed ciphersuites per version */
+
+ /** Callback for printing debug output */
+ void (*f_dbg)(void *, int, const char *, int, const char *);
+ void *p_dbg; /*!< context for the debug function */
+
+ /** Callback for getting (pseudo-)random numbers */
+ int (*f_rng)(void *, unsigned char *, size_t);
+ void *p_rng; /*!< context for the RNG function */
+
+ /** Callback to retrieve a session from the cache */
+ int (*f_get_cache)(void *, mbedtls_ssl_session *);
+ /** Callback to store a session into the cache */
+ int (*f_set_cache)(void *, const mbedtls_ssl_session *);
+ void *p_cache; /*!< context for cache callbacks */
+
+#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
+ /** Callback for setting cert according to SNI extension */
+ int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
+ void *p_sni; /*!< context for SNI callback */
+#endif
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+ /** Callback to customize X.509 certificate chain verification */
+ int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *);
+ void *p_vrfy; /*!< context for X.509 verify calllback */
+#endif
+
+#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+ /** Callback to retrieve PSK key from identity */
+ int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
+ void *p_psk; /*!< context for PSK callback */
+#endif
+
+#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
+ /** Callback to create & write a cookie for ClientHello veirifcation */
+ int (*f_cookie_write)( void *, unsigned char **, unsigned char *,
+ const unsigned char *, size_t );
+ /** Callback to verify validity of a ClientHello cookie */
+ int (*f_cookie_check)( void *, const unsigned char *, size_t,
+ const unsigned char *, size_t );
+ void *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 (*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 (*f_ticket_parse)( void *, mbedtls_ssl_session *, unsigned char *, size_t);
+ void *p_ticket; /*!< context for the ticket callbacks */
+#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */
+
+#if defined(MBEDTLS_SSL_EXPORT_KEYS)
+ /** Callback to export key block and master secret */
+ int (*f_export_keys)( void *, const unsigned char *,
+ const unsigned char *, size_t, size_t, size_t );
+ void *p_export_keys; /*!< context for key export callback */
+#endif
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+ const mbedtls_x509_crt_profile *cert_profile; /*!< verification profile */
+ mbedtls_ssl_key_cert *key_cert; /*!< own certificate/key pair(s) */
+ mbedtls_x509_crt *ca_chain; /*!< trusted CAs */
+ mbedtls_x509_crl *ca_crl; /*!< trusted CAs CRLs */
+#endif /* MBEDTLS_X509_CRT_PARSE_C */
+
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
+ const int *sig_hashes; /*!< allowed signature hashes */
+#endif
+
+#if defined(MBEDTLS_ECP_C)
+ const mbedtls_ecp_group_id *curve_list; /*!< allowed curves */
+#endif
+
+#if defined(MBEDTLS_DHM_C)
+ mbedtls_mpi dhm_P; /*!< prime modulus for DHM */
+ mbedtls_mpi dhm_G; /*!< generator for DHM */
+#endif
+
+#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
+ unsigned char *psk; /*!< pre-shared key */
+ size_t psk_len; /*!< length of the pre-shared key */
+ unsigned char *psk_identity; /*!< identity for PSK negotiation */
+ size_t psk_identity_len;/*!< length of identity */
+#endif
+
+#if defined(MBEDTLS_SSL_ALPN)
+ const char **alpn_list; /*!< ordered list of protocols */
+#endif
+
+ /*
+ * Numerical settings (int then char)
+ */
+
+ uint32_t read_timeout; /*!< timeout for mbedtls_ssl_read (ms) */
+
+#if defined(MBEDTLS_SSL_PROTO_DTLS)
+ uint32_t hs_timeout_min; /*!< initial value of the handshake
+ retransmission timeout (ms) */
+ uint32_t hs_timeout_max; /*!< maximum value of the handshake
+ retransmission timeout (ms) */
+#endif
+
+#if defined(MBEDTLS_SSL_RENEGOTIATION)
+ int renego_max_records; /*!< grace period for renegotiation */
+ unsigned char renego_period[8]; /*!< value of the record counters
+ that triggers renegotiation */
+#endif
+
+#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
+ unsigned int badmac_limit; /*!< limit of records with a bad MAC */
+#endif
+
+#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
+ unsigned int dhm_min_bitlen; /*!< min. bit length of the DHM prime */
+#endif
+
+ unsigned char max_major_ver; /*!< max. major version used */
+ unsigned char max_minor_ver; /*!< max. minor version used */
+ unsigned char min_major_ver; /*!< min. major version used */
+ unsigned char min_minor_ver; /*!< min. minor version used */
+
+ /*
+ * Flags (bitfields)
+ */
+
+ unsigned int endpoint : 1; /*!< 0: client, 1: server */
+ unsigned int transport : 1; /*!< stream (TLS) or datagram (DTLS) */
+ unsigned int authmode : 2; /*!< MBEDTLS_SSL_VERIFY_XXX */
+ /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE */
+ unsigned int allow_legacy_renegotiation : 2 ; /*!< MBEDTLS_LEGACY_XXX */
+#if defined(MBEDTLS_ARC4_C)
+ unsigned int arc4_disabled : 1; /*!< blacklist RC4 ciphersuites? */
+#endif
+#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
+ unsigned int mfl_code : 3; /*!< desired fragment length */
+#endif
+#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
+ unsigned int encrypt_then_mac : 1 ; /*!< negotiate encrypt-then-mac? */
+#endif
+#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
+ unsigned int extended_ms : 1; /*!< negotiate extended master secret? */
+#endif
+#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
+ unsigned int anti_replay : 1; /*!< detect and prevent replay? */
+#endif
+#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
+ unsigned int cbc_record_splitting : 1; /*!< do cbc record splitting */
+#endif
+#if defined(MBEDTLS_SSL_RENEGOTIATION)
+ unsigned int disable_renegotiation : 1; /*!< disable renegotiation? */
+#endif
+#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
+ unsigned int trunc_hmac : 1; /*!< negotiate truncated hmac? */
+#endif
+#if defined(MBEDTLS_SSL_SESSION_TICKETS)
+ unsigned int session_tickets : 1; /*!< use session tickets? */
+#endif
+#if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C)
+ unsigned int fallback : 1; /*!< is this a fallback? */
+#endif
+};
+
+
+struct mbedtls_ssl_context
+{
+ const mbedtls_ssl_config *conf; /*!< configuration information */
+
+ /*
+ * Miscellaneous
+ */
+ int state; /*!< SSL handshake: current state */
+#if defined(MBEDTLS_SSL_RENEGOTIATION)
+ int renego_status; /*!< Initial, in progress, pending? */
+ int renego_records_seen; /*!< Records since renego request, or with DTLS,
+ number of retransmissions of request if
+ renego_max_records is < 0 */
+#endif
+
+ int major_ver; /*!< equal to MBEDTLS_SSL_MAJOR_VERSION_3 */
+ int minor_ver; /*!< either 0 (SSL3) or 1 (TLS1.0) */
+
+#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
+ unsigned badmac_seen; /*!< records with a bad MAC received */
+#endif
+
+ mbedtls_ssl_send_t *f_send; /*!< Callback for network send */
+ mbedtls_ssl_recv_t *f_recv; /*!< Callback for network receive */
+ mbedtls_ssl_recv_timeout_t *f_recv_timeout;
+ /*!< Callback for network receive with timeout */
+
+ void *p_bio; /*!< context for I/O operations */
+
+ /*
+ * Session layer
+ */
+ mbedtls_ssl_session *session_in; /*!< current session data (in) */
+ mbedtls_ssl_session *session_out; /*!< current session data (out) */
+ mbedtls_ssl_session *session; /*!< negotiated session data */
+ mbedtls_ssl_session *session_negotiate; /*!< session data in negotiation */
+
+ mbedtls_ssl_handshake_params *handshake; /*!< params required only during
+ the handshake process */
+
+ /*
+ * Record layer transformations
+ */
+ mbedtls_ssl_transform *transform_in; /*!< current transform params (in) */
+ mbedtls_ssl_transform *transform_out; /*!< current transform params (in) */
+ mbedtls_ssl_transform *transform; /*!< negotiated transform params */
+ mbedtls_ssl_transform *transform_negotiate; /*!< transform params in negotiation */
+
+ /*
+ * Timers
+ */
+ void *p_timer; /*!< context for the timer callbacks */
+
+ mbedtls_ssl_set_timer_t *f_set_timer; /*!< set timer callback */
+ mbedtls_ssl_get_timer_t *f_get_timer; /*!< get timer callback */
+
+ /*
+ * Record layer (incoming data)
+ */
+ unsigned char *in_buf; /*!< input buffer */
+ unsigned char *in_ctr; /*!< 64-bit incoming message counter
+ TLS: maintained by us
+ DTLS: read from peer */
+ unsigned char *in_hdr; /*!< start of record header */
+ unsigned char *in_len; /*!< two-bytes message length field */
+ unsigned char *in_iv; /*!< ivlen-byte IV */
+ unsigned char *in_msg; /*!< message contents (in_iv+ivlen) */
+ unsigned char *in_offt; /*!< read offset in application data */
+
+ int in_msgtype; /*!< record header: message type */
+ size_t in_msglen; /*!< record header: message length */
+ size_t in_left; /*!< amount of data read so far */
+#if defined(MBEDTLS_SSL_PROTO_DTLS)
+ uint16_t in_epoch; /*!< DTLS epoch for incoming records */
+ size_t next_record_offset; /*!< offset of the next record in datagram
+ (equal to in_left if none) */
+#endif
+#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
+ uint64_t in_window_top; /*!< last validated record seq_num */
+ uint64_t in_window; /*!< bitmask for replay detection */
+#endif
+
+ size_t in_hslen; /*!< current handshake message length,
+ including the handshake header */
+ int nb_zero; /*!< # of 0-length encrypted messages */
+ int record_read; /*!< record is already present */
+
+ /*
+ * Record layer (outgoing data)
+ */
+ unsigned char *out_buf; /*!< output buffer */
+ unsigned char *out_ctr; /*!< 64-bit outgoing message counter */
+ unsigned char *out_hdr; /*!< start of record header */
+ unsigned char *out_len; /*!< two-bytes message length field */
+ unsigned char *out_iv; /*!< ivlen-byte IV */
+ unsigned char *out_msg; /*!< message contents (out_iv+ivlen) */
+
+ int out_msgtype; /*!< record header: message type */
+ size_t out_msglen; /*!< record header: message length */
+ size_t out_left; /*!< amount of data not yet written */
+
+#if defined(MBEDTLS_ZLIB_SUPPORT)
+ unsigned char *compress_buf; /*!< zlib data buffer */
+#endif
+#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
+ signed char split_done; /*!< current record already splitted? */
+#endif
+
+ /*
+ * PKI layer
+ */
+ int client_auth; /*!< flag for client auth. */
+
+ /*
+ * User settings
+ */
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+ char *hostname; /*!< expected peer CN for verification
+ (and SNI if available) */
+#endif
+
+#if defined(MBEDTLS_SSL_ALPN)
+ const char *alpn_chosen; /*!< negotiated protocol */
+#endif
+
+ /*
+ * Information for DTLS hello verify
+ */
+#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
+ unsigned char *cli_id; /*!< transport-level ID of the client */
+ size_t cli_id_len; /*!< length of cli_id */
+#endif
+
+ /*
+ * Secure renegotiation
+ */
+ /* needed to know when to send extension on server */
+ int secure_renegotiation; /*!< does peer support legacy or
+ secure renegotiation */
+#if defined(MBEDTLS_SSL_RENEGOTIATION)
+ size_t verify_data_len; /*!< length of verify data stored */
+ char own_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
+ char peer_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!< previous handshake verify data */
+#endif
+};
+
+#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
+
+#define MBEDTLS_SSL_CHANNEL_OUTBOUND 0
+#define MBEDTLS_SSL_CHANNEL_INBOUND 1
+
+extern int (*mbedtls_ssl_hw_record_init)(mbedtls_ssl_context *ssl,
+ const unsigned char *key_enc, const unsigned char *key_dec,
+ size_t keylen,
+ const unsigned char *iv_enc, const unsigned char *iv_dec,
+ size_t ivlen,
+ const unsigned char *mac_enc, const unsigned char *mac_dec,
+ size_t maclen);
+extern int (*mbedtls_ssl_hw_record_activate)(mbedtls_ssl_context *ssl, int direction);
+extern int (*mbedtls_ssl_hw_record_reset)(mbedtls_ssl_context *ssl);
+extern int (*mbedtls_ssl_hw_record_write)(mbedtls_ssl_context *ssl);
+extern int (*mbedtls_ssl_hw_record_read)(mbedtls_ssl_context *ssl);
+extern int (*mbedtls_ssl_hw_record_finish)(mbedtls_ssl_context *ssl);
+#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
+
+/**
+ * \brief Returns the list of ciphersuites supported by the SSL/TLS module.
+ *
+ * \return a statically allocated array of ciphersuites, the last
+ * entry is 0.
+ */
+const int *mbedtls_ssl_list_ciphersuites( void );
+
+/**
+ * \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 Modifying the conf structure after it has been used in this
+ * function is unsupported!
+ *
+ * \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,
+ MBEDTLS_ERR_SSL_HW_ACCEL_FAILED or
+ * MBEDTLS_ERR_SSL_COMPRESSION_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_X509_CRT_PARSE_C)
+/**
+ * \brief Set the verification callback (Optional).
+ *
+ * If set, the verify callback is called for each
+ * certificate in the chain. For implementation
+ * information, please see \c x509parse_verify()
+ *
+ * \param conf SSL configuration
+ * \param f_vrfy verification function
+ * \param p_vrfy verification parameter
+ */
+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
+ * \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 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_timout != 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_sent_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 );
+
+/**
+ * \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 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 fallow.
+ *
+ * \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://tls.mbed.org/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 );
+
+/**
+ * \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 );
+
+#if defined(MBEDTLS_SSL_EXPORT_KEYS)
+/**
+ * \brief Callback type: Export key block and master secret
+ *
+ * \note This is required for certain uses of TLS, e.g. EAP-TLS
+ * (RFC 5216) and Thread. The key pointers are ephemeral and
+ * therefore must not be stored. The master secret and keys
+ * should not be used directly except as an input to a key
+ * derivation function.
+ *
+ * \param p_expkey Context for the callback
+ * \param ms Pointer to master secret (fixed length: 48 bytes)
+ * \param kb Pointer to key block, see RFC 5246 section 6.3
+ * (variable length: 2 * maclen + 2 * keylen + 2 * ivlen).
+ * \param maclen MAC length
+ * \param keylen Key length
+ * \param ivlen IV length
+ *
+ * \return 0 if successful, or
+ * a specific MBEDTLS_ERR_XXX code.
+ */
+typedef int mbedtls_ssl_export_keys_t( void *p_expkey,
+ const unsigned char *ms,
+ const unsigned char *kb,
+ size_t maclen,
+ size_t keylen,
+ size_t ivlen );
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
+
+/**
+ * \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 */
+
+#if defined(MBEDTLS_SSL_EXPORT_KEYS)
+/**
+ * \brief Configure key export callback.
+ * (Default: none.)
+ *
+ * \note See \c mbedtls_ssl_export_keys_t.
+ *
+ * \param conf SSL configuration context
+ * \param f_export_keys Callback for exporting keys
+ * \param p_export_keys Context for the callback
+ */
+void mbedtls_ssl_conf_export_keys_cb( mbedtls_ssl_config *conf,
+ mbedtls_ssl_export_keys_t *f_export_keys,
+ void *p_export_keys );
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
+
+/**
+ * \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 */
+
+#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
+/**
+ * \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 ot 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 );
+#endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */
+
+#if defined(MBEDTLS_SSL_PROTO_DTLS)
+/**
+ * \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 parmater (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,
+ int (*f_get_cache)(void *, mbedtls_ssl_session *),
+ int (*f_set_cache)(void *, const mbedtls_ssl_session *) );
+#endif /* MBEDTLS_SSL_SRV_C */
+
+#if defined(MBEDTLS_SSL_CLI_C)
+/**
+ * \brief Request resumption of session (client-side only)
+ * Session data is copied from presented session structure.
+ *
+ * \param ssl SSL context
+ * \param session session context
+ *
+ * \return 0 if successful,
+ * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed,
+ * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or
+ * arguments are otherwise invalid
+ *
+ * \sa mbedtls_ssl_get_session()
+ */
+int mbedtls_ssl_set_session( mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session );
+#endif /* MBEDTLS_SSL_CLI_C */
+
+/**
+ * \brief Set the list of allowed ciphersuites and the preference
+ * order. First in the list has the highest preference.
+ * (Overrides all version-specific lists)
+ *
+ * The ciphersuites array is not copied, and must remain
+ * valid for the lifetime of the ssl_config.
+ *
+ * Note: The server uses its own preferences
+ * over the preference of the client unless
+ * MBEDTLS_SSL_SRV_RESPECT_CLIENT_PREFERENCE is defined!
+ *
+ * \param conf SSL configuration
+ * \param ciphersuites 0-terminated list of allowed ciphersuites
+ */
+void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf,
+ const int *ciphersuites );
+
+/**
+ * \brief Set the list of allowed ciphersuites and the
+ * preference order for a specific version of the protocol.
+ * (Only useful on the server side)
+ *
+ * The ciphersuites array is not copied, and must remain
+ * valid for the lifetime of the ssl_config.
+ *
+ * \param conf SSL configuration
+ * \param ciphersuites 0-terminated list of allowed ciphersuites
+ * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3
+ * supported)
+ * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
+ * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
+ * MBEDTLS_SSL_MINOR_VERSION_3 supported)
+ *
+ * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0
+ * and MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
+ */
+void mbedtls_ssl_conf_ciphersuites_for_version( mbedtls_ssl_config *conf,
+ const int *ciphersuites,
+ int major, int minor );
+
+#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
+ *
+ * \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 );
+
+/**
+ * \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 mutliple 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 CertficateRequest 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.
+ *
+ * \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_KEY_EXCHANGE__SOME__PSK_ENABLED)
+/**
+ * \brief Set the Pre Shared Key (PSK) and the expected identity name
+ *
+ * \note This is mainly useful for clients. Servers will usually
+ * want to use \c mbedtls_ssl_conf_psk_cb() instead.
+ *
+ * \note Currently clients can only register one pre-shared key.
+ * In other words, the servers' identity hint is ignored.
+ * Support for setting multiple PSKs on clients and selecting
+ * one based on the identity hint is not a planned feature but
+ * feedback is welcomed.
+ *
+ * \param conf SSL configuration
+ * \param psk pointer to the pre-shared key
+ * \param psk_len pre-shared key length
+ * \param psk_identity pointer to the pre-shared key identity
+ * \param psk_identity_len identity key length
+ *
+ * \return 0 if successful or MBEDTLS_ERR_SSL_ALLOC_FAILED
+ */
+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 );
+
+
+/**
+ * \brief Set the Pre Shared Key (PSK) for the current handshake
+ *
+ * \note This should only be called inside the PSK callback,
+ * ie the function passed to \c mbedtls_ssl_conf_psk_cb().
+ *
+ * \param ssl SSL context
+ * \param psk pointer to the pre-shared key
+ * \param psk_len pre-shared key length
+ *
+ * \return 0 if successful or MBEDTLS_ERR_SSL_ALLOC_FAILED
+ */
+int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl,
+ const unsigned char *psk, size_t psk_len );
+
+/**
+ * \brief Set the PSK callback (server-side only).
+ *
+ * If set, the PSK callback is called for each
+ * handshake where a PSK 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: (void *parameter,
+ * mbedtls_ssl_context *ssl, const unsigned char *psk_identity,
+ * size_t identity_len)
+ * If a valid PSK identity is found, the callback should use
+ * \c mbedtls_ssl_set_hs_psk() on the ssl context to set the
+ * correct PSK and return 0.
+ * Any other return value will result in a denied PSK identity.
+ *
+ * \note If you set a PSK callback using this function, then you
+ * don't need to set a PSK key and identity using
+ * \c mbedtls_ssl_conf_psk().
+ *
+ * \param conf SSL configuration
+ * \param f_psk PSK identity function
+ * \param p_psk PSK identity parameter
+ */
+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_KEY_EXCHANGE__SOME__PSK_ENABLED */
+
+#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_SRV_C)
+/**
+ * \brief Set the Diffie-Hellman public P and G values,
+ * read as hexadecimal strings (server-side only)
+ * (Default: MBEDTLS_DHM_RFC5114_MODP_2048_[PG])
+ *
+ * \param conf SSL configuration
+ * \param dhm_P Diffie-Hellman-Merkle modulus
+ * \param dhm_G Diffie-Hellman-Merkle generator
+ *
+ * \return 0 if successful
+ */
+int mbedtls_ssl_conf_dh_param( mbedtls_ssl_config *conf, const char *dhm_P, const char *dhm_G );
+
+/**
+ * \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_C)
+/**
+ * \brief Set the allowed curves in order of preference.
+ * (Default: all defined curves.)
+ *
+ * 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.
+ *
+ * \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).
+ *
+ * \param conf SSL configuration
+ * \param curves Ordered list of allowed curves,
+ * terminated by MBEDTLS_ECP_DP_NONE.
+ */
+void mbedtls_ssl_conf_curves( mbedtls_ssl_config *conf,
+ const mbedtls_ecp_group_id *curves );
+#endif /* MBEDTLS_ECP_C */
+
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
+/**
+ * \brief Set the allowed hashes for signatures during the handshake.
+ * (Default: all available hashes except MD5.)
+ *
+ * \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).
+ *
+ * \param conf SSL configuration
+ * \param hashes Ordered list of allowed signature hashes,
+ * terminated by \c MBEDTLS_MD_NONE.
+ */
+void mbedtls_ssl_conf_sig_hashes( mbedtls_ssl_config *conf,
+ const int *hashes );
+#endif /* MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED */
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+/**
+ * \brief Set the hostname to check against the received server
+ * certificate. It sets the ServerName TLS extension too,
+ * if the extension is enabled.
+ * (client-side only)
+ *
+ * \param ssl SSL context
+ * \param hostname the server hostname
+ *
+ * \return 0 if successful or MBEDTLS_ERR_SSL_ALLOC_FAILED
+ */
+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 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.
+ *
+ * \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.
+ *
+ * \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 );
+
+/**
+ * \brief Set authmode for the current handshake.
+ *
+ * \note Same as \c mbedtls_ssl_conf_authmode() but for use within
+ * the SNI 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 must either set a default cert, or
+ * return non-zero to abort the handshake at this point.
+ *
+ * \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().
+ *
+ * \param ssl SSL context
+ * \param pw EC J-PAKE password (pre-shared secret)
+ * \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 );
+#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 atleast 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 Protcol name, or NULL if no protocol was negotiated.
+ */
+const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl );
+#endif /* MBEDTLS_SSL_ALPN */
+
+/**
+ * \brief Set the maximum supported version sent from the client side
+ * and/or accepted at the server side
+ * (Default: MBEDTLS_SSL_MAX_MAJOR_VERSION, MBEDTLS_SSL_MAX_MINOR_VERSION)
+ *
+ * \note This ignores ciphersuites from higher versions.
+ *
+ * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and
+ * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
+ *
+ * \param conf SSL configuration
+ * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
+ * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
+ * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
+ * MBEDTLS_SSL_MINOR_VERSION_3 supported)
+ */
+void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor );
+
+/**
+ * \brief Set the minimum accepted SSL/TLS protocol version
+ * (Default: TLS 1.0)
+ *
+ * \note Input outside of the SSL_MAX_XXXXX_VERSION and
+ * SSL_MIN_XXXXX_VERSION range is ignored.
+ *
+ * \note MBEDTLS_SSL_MINOR_VERSION_0 (SSL v3) should be avoided.
+ *
+ * \note With DTLS, use MBEDTLS_SSL_MINOR_VERSION_2 for DTLS 1.0 and
+ * MBEDTLS_SSL_MINOR_VERSION_3 for DTLS 1.2
+ *
+ * \param conf SSL configuration
+ * \param major Major version number (only MBEDTLS_SSL_MAJOR_VERSION_3 supported)
+ * \param minor Minor version number (MBEDTLS_SSL_MINOR_VERSION_0,
+ * MBEDTLS_SSL_MINOR_VERSION_1 and MBEDTLS_SSL_MINOR_VERSION_2,
+ * MBEDTLS_SSL_MINOR_VERSION_3 supported)
+ */
+void mbedtls_ssl_conf_min_version( mbedtls_ssl_config *conf, int major, int minor );
+
+#if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C)
+/**
+ * \brief Set the fallback flag (client-side only).
+ * (Default: MBEDTLS_SSL_IS_NOT_FALLBACK).
+ *
+ * \note Set to MBEDTLS_SSL_IS_FALLBACK when preparing a fallback
+ * connection, that is a connection with max_version set to a
+ * lower value than the value you're willing to use. Such
+ * fallback connections are not recommended but are sometimes
+ * necessary to interoperate with buggy (version-intolerant)
+ * servers.
+ *
+ * \warning You should NOT set this to MBEDTLS_SSL_IS_FALLBACK for
+ * non-fallback connections! This would appear to work for a
+ * while, then cause failures when the server is upgraded to
+ * support a newer TLS version.
+ *
+ * \param conf SSL configuration
+ * \param fallback MBEDTLS_SSL_IS_NOT_FALLBACK or MBEDTLS_SSL_IS_FALLBACK
+ */
+void mbedtls_ssl_conf_fallback( mbedtls_ssl_config *conf, char fallback );
+#endif /* MBEDTLS_SSL_FALLBACK_SCSV && MBEDTLS_SSL_CLI_C */
+
+#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_ARC4_C)
+/**
+ * \brief Disable or enable support for RC4
+ * (Default: MBEDTLS_SSL_ARC4_DISABLED)
+ *
+ * \warning Use of RC4 in DTLS/TLS has been prohibited by RFC 7465
+ * for security reasons. Use at your own risk.
+ *
+ * \note This function is deprecated and will likely be removed in
+ * a future version of the library.
+ * RC4 is disabled by default at compile time and needs to be
+ * actively enabled for use with legacy systems.
+ *
+ * \param conf SSL configuration
+ * \param arc4 MBEDTLS_SSL_ARC4_ENABLED or MBEDTLS_SSL_ARC4_DISABLED
+ */
+void mbedtls_ssl_conf_arc4_support( mbedtls_ssl_config *conf, char arc4 );
+#endif /* MBEDTLS_ARC4_C */
+
+#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
+/**
+ * \brief Set the maximum fragment length to emit and/or negotiate
+ * (Default: MBEDTLS_SSL_MAX_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)
+ *
+ * \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_TRUNCATED_HMAC)
+/**
+ * \brief Activate negotiation of truncated HMAC
+ * (Default: MBEDTLS_SSL_TRUNC_HMAC_DISABLED)
+ *
+ * \param conf SSL configuration
+ * \param truncate Enable or disable (MBEDTLS_SSL_TRUNC_HMAC_ENABLED or
+ * MBEDTLS_SSL_TRUNC_HMAC_DISABLED)
+ */
+void mbedtls_ssl_conf_truncated_hmac( mbedtls_ssl_config *conf, int truncate );
+#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
+
+#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
+/**
+ * \brief Enable / Disable 1/n-1 record splitting
+ * (Default: MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED)
+ *
+ * \note Only affects SSLv3 and TLS 1.0, not higher versions.
+ * Does not affect non-CBC ciphersuites in any version.
+ *
+ * \param conf SSL configuration
+ * \param split MBEDTLS_SSL_CBC_RECORD_SPLITTING_ENABLED or
+ * MBEDTLS_SSL_CBC_RECORD_SPLITTING_DISABLED
+ */
+void mbedtls_ssl_conf_cbc_record_splitting( mbedtls_ssl_config *conf, char split );
+#endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */
+
+#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_RENEGOTIATION)
+/**
+ * \brief Enable / Disable renegotiation support for connection when
+ * initiated by peer
+ * (Default: MBEDTLS_SSL_RENEGOTIATION_DISABLED)
+ *
+ * \warning It is recommended to always disable renegotation 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 retransmited 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: 2^64 - 256.)
+ *
+ * Renegotiation is automatically triggered when a record
+ * counter (outgoing or ingoing) 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".
+ *
+ * \param conf SSL configuration
+ * \param period The threshold value: a big-endian 64-bit number.
+ * Set to 2^64 - 1 to disable periodic renegotiation
+ */
+void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf,
+ const unsigned char period[8] );
+#endif /* MBEDTLS_SSL_RENEGOTIATION */
+
+/**
+ * \brief Return the number of data bytes available to read
+ *
+ * \param ssl SSL context
+ *
+ * \return how many bytes are available in the read buffer
+ */
+size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl );
+
+/**
+ * \brief Return the result of the certificate verification
+ *
+ * \param ssl SSL context
+ *
+ * \return 0 if successful,
+ * -1 if result is not available (eg because the handshake was
+ * aborted too early), or
+ * a combination of BADCERT_xxx and BADCRL_xxx flags, see
+ * x509.h
+ */
+uint32_t mbedtls_ssl_get_verify_result( 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 current SSL version (SSLv3/TLSv1/etc)
+ *
+ * \param ssl SSL context
+ *
+ * \return a string containing the SSL 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, or
+ * MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE if compression is
+ * enabled, which makes expansion much less predictable
+ */
+int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl );
+
+#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
+/**
+ * \brief Return the maximum fragment length (payload, in bytes).
+ * This is the value negotiated with peer if any,
+ * or the locally configured value.
+ *
+ * \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.
+ *
+ * \param ssl SSL context
+ *
+ * \return Current maximum fragment length.
+ */
+size_t mbedtls_ssl_get_max_frag_len( const mbedtls_ssl_context *ssl );
+#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+/**
+ * \brief Return the peer certificate from the current connection
+ *
+ * Note: Can be NULL in case no certificate was sent during
+ * the handshake. Different calls for the same connection can
+ * return the same or different pointers for the same
+ * certificate and even a different certificate altogether.
+ * The peer cert CAN change in a single connection if
+ * renegotiation is performed.
+ *
+ * \param ssl SSL context
+ *
+ * \return the current peer certificate
+ */
+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 Save session in order to resume it later (client-side only)
+ * Session data is copied to presented session structure.
+ *
+ * \warning Currently, peer certificate is lost in the operation.
+ *
+ * \param ssl SSL context
+ * \param session session context
+ *
+ * \return 0 if successful,
+ * MBEDTLS_ERR_SSL_ALLOC_FAILED if memory allocation failed,
+ * MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used server-side or
+ * arguments are otherwise invalid
+ *
+ * \sa mbedtls_ssl_set_session()
+ */
+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 0 if successful, or
+ * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or
+ * MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED (see below), or
+ * a specific SSL error code.
+ *
+ * \note If this function returns something other than 0 or
+ * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context
+ * becomes unusable, and you should 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.
+ */
+int mbedtls_ssl_handshake( mbedtls_ssl_context *ssl );
+
+/**
+ * \brief Perform a single step of the SSL handshake
+ *
+ * \note The state of the context (ssl->state) will be at
+ * the next state after execution of this function. Do not
+ * call this function if state is MBEDTLS_SSL_HANDSHAKE_OVER.
+ *
+ * \note If this function returns something other than 0 or
+ * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context
+ * becomes unusable, and you should 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.
+ *
+ * \param ssl SSL context
+ *
+ * \return 0 if successful, or
+ * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or
+ * a specific SSL error code.
+ */
+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.
+ *
+ * \note If this function returns something other than 0 or
+ * MBEDTLS_ERR_SSL_WANT_READ/WRITE, then the ssl context
+ * becomes unusable, and you should 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 number of bytes read, or
+ * 0 for EOF, or
+ * MBEDTLS_ERR_SSL_WANT_READ or MBEDTLS_ERR_SSL_WANT_WRITE, or
+ * MBEDTLS_ERR_SSL_CLIENT_RECONNECT (see below), or
+ * another negative error code.
+ *
+ * \note If this function returns something other than a positive
+ * value or MBEDTLS_ERR_SSL_WANT_READ/WRITE or
+ * MBEDTLS_ERR_SSL_CLIENT_RECONNECT, then the ssl context
+ * becomes unusable, and you should 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 return 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 beeen reset internally). Either way, you
+ * should 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!
+ */
+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 number of bytes actually written (may be less than len),
+ * or MBEDTLS_ERR_SSL_WANT_WRITE of MBEDTLS_ERR_SSL_WANT_READ,
+ * or another negative error code.
+ *
+ * \note If this function returns something other than a positive
+ * value or MBEDTLS_ERR_SSL_WANT_READ/WRITE, the ssl context
+ * becomes unusable, and you should 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 positive value.
+ *
+ * \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_frag_len() may be used to query the
+ * active maximum fragment length.
+ */
+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, then the ssl context
+ * becomes unusable, and you should 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, then the ssl context
+ * becomes unusable, and you should 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 );
+
+/**
+ * \brief Free referenced items in an SSL context and clear memory
+ *
+ * \param ssl SSL context
+ */
+void mbedtls_ssl_free( mbedtls_ssl_context *ssl );
+
+/**
+ * \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 relevent fields yourself.
+ *
+ * \param conf SSL configuration context
+ */
+void mbedtls_ssl_config_init( mbedtls_ssl_config *conf );
+
+/**
+ * \brief Load reasonnable 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
+ *
+ * \param session SSL session
+ */
+void mbedtls_ssl_session_free( mbedtls_ssl_session *session );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ssl.h */
