ssl.h

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/*
 *  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)

#if defined(MBEDTLS_DEPRECATED_WARNING)
#warning "Record compression support via MBEDTLS_ZLIB_SUPPORT is deprecated and will be removed in the next major revision of the library"
#endif

#if defined(MBEDTLS_DEPRECATED_REMOVED)
#error "Record compression support via MBEDTLS_ZLIB_SUPPORT is deprecated and cannot be used if MBEDTLS_DEPRECATED_REMOVED is set"
#endif

#include "zlib.h"
#endif

#if defined(MBEDTLS_HAVE_TIME)
#include "platform_time.h"
#endif

/*
 * SSL Error codes
 */
#define MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE               -0x7080  
#define MBEDTLS_ERR_SSL_BAD_INPUT_DATA                    -0x7100  
#define MBEDTLS_ERR_SSL_INVALID_MAC                       -0x7180  
#define MBEDTLS_ERR_SSL_INVALID_RECORD                    -0x7200  
#define MBEDTLS_ERR_SSL_CONN_EOF                          -0x7280  
#define MBEDTLS_ERR_SSL_UNKNOWN_CIPHER                    -0x7300  
#define MBEDTLS_ERR_SSL_NO_CIPHER_CHOSEN                  -0x7380  
#define MBEDTLS_ERR_SSL_NO_RNG                            -0x7400  
#define MBEDTLS_ERR_SSL_NO_CLIENT_CERTIFICATE             -0x7480  
#define MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE             -0x7500  
#define MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED              -0x7580  
#define MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED              -0x7600  
#define MBEDTLS_ERR_SSL_CA_CHAIN_REQUIRED                 -0x7680  
#define MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE                -0x7700  
#define MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE               -0x7780  
#define MBEDTLS_ERR_SSL_PEER_VERIFY_FAILED                -0x7800  
#define MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY                 -0x7880  
#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO               -0x7900  
#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO               -0x7980  
#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE                -0x7A00  
#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST        -0x7A80  
#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE        -0x7B00  
#define MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE          -0x7B80  
#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE        -0x7C00  
#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP     -0x7C80  
#define MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_CS     -0x7D00  
#define MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY         -0x7D80  
#define MBEDTLS_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC         -0x7E00  
#define MBEDTLS_ERR_SSL_BAD_HS_FINISHED                   -0x7E80  
#define MBEDTLS_ERR_SSL_ALLOC_FAILED                      -0x7F00  
#define MBEDTLS_ERR_SSL_HW_ACCEL_FAILED                   -0x7F80  
#define MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH              -0x6F80  
#define MBEDTLS_ERR_SSL_COMPRESSION_FAILED                -0x6F00  
#define MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION           -0x6E80  
#define MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET         -0x6E00  
#define MBEDTLS_ERR_SSL_SESSION_TICKET_EXPIRED            -0x6D80  
#define MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH                  -0x6D00  
#define MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY                  -0x6C80  
#define MBEDTLS_ERR_SSL_INTERNAL_ERROR                    -0x6C00  
#define MBEDTLS_ERR_SSL_COUNTER_WRAPPING                  -0x6B80  
#define MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO       -0x6B00  
#define MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED             -0x6A80  
#define MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL                  -0x6A00  
#define MBEDTLS_ERR_SSL_NO_USABLE_CIPHERSUITE             -0x6980  
#define MBEDTLS_ERR_SSL_WANT_READ                         -0x6900  
#define MBEDTLS_ERR_SSL_WANT_WRITE                        -0x6880  
#define MBEDTLS_ERR_SSL_TIMEOUT                           -0x6800  
#define MBEDTLS_ERR_SSL_CLIENT_RECONNECT                  -0x6780  
#define MBEDTLS_ERR_SSL_UNEXPECTED_RECORD                 -0x6700  
#define MBEDTLS_ERR_SSL_NON_FATAL                         -0x6680  
#define MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH               -0x6600  
#define MBEDTLS_ERR_SSL_CONTINUE_PROCESSING               -0x6580  
#define MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS                 -0x6500  
#define MBEDTLS_ERR_SSL_EARLY_MESSAGE                     -0x6480  
#define MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS                -0x7000  
/*
 * Various constants
 */
#define MBEDTLS_SSL_MAJOR_VERSION_3             3
#define MBEDTLS_SSL_MINOR_VERSION_0             0   
#define MBEDTLS_SSL_MINOR_VERSION_1             1   
#define MBEDTLS_SSL_MINOR_VERSION_2             2   
#define MBEDTLS_SSL_MINOR_VERSION_3             3   
#define MBEDTLS_SSL_TRANSPORT_STREAM            0   
#define MBEDTLS_SSL_TRANSPORT_DATAGRAM          1   
#define MBEDTLS_SSL_MAX_HOST_NAME_LEN           255 
/* 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   
#define MBEDTLS_SSL_MAX_FRAG_LEN_512            1   
#define MBEDTLS_SSL_MAX_FRAG_LEN_1024           2   
#define MBEDTLS_SSL_MAX_FRAG_LEN_2048           3   
#define MBEDTLS_SSL_MAX_FRAG_LEN_4096           4   
#define MBEDTLS_SSL_MAX_FRAG_LEN_INVALID        5   
#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

#define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED       1
#define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED      0

/*
 * 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

#if !defined(MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME)
#define MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME     86400 
#endif

/*
 * Maximum fragment length in bytes,
 * determines the size of each of the two internal I/O buffers.
 *
 * Note: the RFC defines the default size of SSL / TLS messages. If you
 * change the value here, other clients / servers may not be able to
 * communicate with you anymore. Only change this value if you control
 * both sides of the connection and have it reduced at both sides, or
 * if you're using the Max Fragment Length extension and you know all your
 * peers are using it too!
 */
#if !defined(MBEDTLS_SSL_MAX_CONTENT_LEN)
#define MBEDTLS_SSL_MAX_CONTENT_LEN         16384   
#endif

#if !defined(MBEDTLS_SSL_IN_CONTENT_LEN)
#define MBEDTLS_SSL_IN_CONTENT_LEN MBEDTLS_SSL_MAX_CONTENT_LEN
#endif

#if !defined(MBEDTLS_SSL_OUT_CONTENT_LEN)
#define MBEDTLS_SSL_OUT_CONTENT_LEN MBEDTLS_SSL_MAX_CONTENT_LEN
#endif

/*
 * Maximum number of heap-allocated bytes for the purpose of
 * DTLS handshake message reassembly and future message buffering.
 */
#if !defined(MBEDTLS_SSL_DTLS_MAX_BUFFERING)
#define MBEDTLS_SSL_DTLS_MAX_BUFFERING 32768
#endif

/* \} 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   
#define MBEDTLS_SSL_FALLBACK_SCSV_VALUE         0x5600 
/*
 * 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;

typedef int mbedtls_ssl_send_t( void *ctx,
                                const unsigned char *buf,
                                size_t len );

typedef int mbedtls_ssl_recv_t( void *ctx,
                                unsigned char *buf,
                                size_t len );

typedef int mbedtls_ssl_recv_timeout_t( void *ctx,
                                        unsigned char *buf,
                                        size_t len,
                                        uint32_t timeout );
typedef void mbedtls_ssl_set_timer_t( void * ctx,
                                      uint32_t int_ms,
                                      uint32_t fin_ms );

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;
typedef struct mbedtls_ssl_sig_hash_set_t mbedtls_ssl_sig_hash_set_t;
#if defined(MBEDTLS_X509_CRT_PARSE_C)
typedef struct mbedtls_ssl_key_cert mbedtls_ssl_key_cert;
#endif
#if defined(MBEDTLS_SSL_PROTO_DTLS)
typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item;
#endif

#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
#if defined(MBEDTLS_X509_CRT_PARSE_C)

typedef int mbedtls_ssl_async_sign_t( mbedtls_ssl_context *ssl,
                                      mbedtls_x509_crt *cert,
                                      mbedtls_md_type_t md_alg,
                                      const unsigned char *hash,
                                      size_t hash_len );

typedef int mbedtls_ssl_async_decrypt_t( mbedtls_ssl_context *ssl,
                                         mbedtls_x509_crt *cert,
                                         const unsigned char *input,
                                         size_t input_len );
#endif /* MBEDTLS_X509_CRT_PARSE_C */

typedef int mbedtls_ssl_async_resume_t( mbedtls_ssl_context *ssl,
                                        unsigned char *output,
                                        size_t *output_len,
                                        size_t output_size );

typedef void mbedtls_ssl_async_cancel_t( mbedtls_ssl_context *ssl );
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */

/*
 * This structure is used for storing current session data.
 */
struct mbedtls_ssl_session
{
#if defined(MBEDTLS_HAVE_TIME)
    mbedtls_time_t start;       
#endif
    int ciphersuite;            
    int compression;            
    size_t id_len;              
    unsigned char id[32];       
    unsigned char master[48];   
#if defined(MBEDTLS_X509_CRT_PARSE_C)
    mbedtls_x509_crt *peer_cert;        
#endif /* MBEDTLS_X509_CRT_PARSE_C */
    uint32_t verify_result;          
#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
    unsigned char *ticket;      
    size_t ticket_len;          
    uint32_t ticket_lifetime;   
#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_CLI_C */

#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
    unsigned char mfl_code;     
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */

#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
    int trunc_hmac;             
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */

#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
    int encrypt_then_mac;       
#endif
};

struct mbedtls_ssl_config
{
    /* Group items by size (largest first) to minimize padding overhead */

    /*
     * Pointers
     */

    const int *ciphersuite_list[4]; 
    void (*f_dbg)(void *, int, const char *, int, const char *);
    void *p_dbg;                    
    int  (*f_rng)(void *, unsigned char *, size_t);
    void *p_rng;                    
    int (*f_get_cache)(void *, mbedtls_ssl_session *);
    int (*f_set_cache)(void *, const mbedtls_ssl_session *);
    void *p_cache;                  
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)

    int (*f_sni)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
    void *p_sni;                    
#endif

#if defined(MBEDTLS_X509_CRT_PARSE_C)

    int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *);
    void *p_vrfy;                   
#endif

#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)

    int (*f_psk)(void *, mbedtls_ssl_context *, const unsigned char *, size_t);
    void *p_psk;                    
#endif

#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)

    int (*f_cookie_write)( void *, unsigned char **, unsigned char *,
                           const unsigned char *, size_t );
    int (*f_cookie_check)( void *, const unsigned char *, size_t,
                           const unsigned char *, size_t );
    void *p_cookie;                 
#endif

#if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_SRV_C)

    int (*f_ticket_write)( void *, const mbedtls_ssl_session *,
            unsigned char *, const unsigned char *, size_t *, uint32_t * );
    int (*f_ticket_parse)( void *, mbedtls_ssl_session *, unsigned char *, size_t);
    void *p_ticket;                 
#endif /* MBEDTLS_SSL_SESSION_TICKETS && MBEDTLS_SSL_SRV_C */

#if defined(MBEDTLS_SSL_EXPORT_KEYS)

    int (*f_export_keys)( void *, const unsigned char *,
            const unsigned char *, size_t, size_t, size_t );
    void *p_export_keys;            
#endif

#if defined(MBEDTLS_X509_CRT_PARSE_C)
    const mbedtls_x509_crt_profile *cert_profile; 
    mbedtls_ssl_key_cert *key_cert; 
    mbedtls_x509_crt *ca_chain;     
    mbedtls_x509_crl *ca_crl;       
#endif /* MBEDTLS_X509_CRT_PARSE_C */

#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
#if defined(MBEDTLS_X509_CRT_PARSE_C)
    mbedtls_ssl_async_sign_t *f_async_sign_start; 
    mbedtls_ssl_async_decrypt_t *f_async_decrypt_start; 
#endif /* MBEDTLS_X509_CRT_PARSE_C */
    mbedtls_ssl_async_resume_t *f_async_resume; 
    mbedtls_ssl_async_cancel_t *f_async_cancel; 
    void *p_async_config_data; 
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */

#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
    const int *sig_hashes;          
#endif

#if defined(MBEDTLS_ECP_C)
    const mbedtls_ecp_group_id *curve_list; 
#endif

#if defined(MBEDTLS_DHM_C)
    mbedtls_mpi dhm_P;              
    mbedtls_mpi dhm_G;              
#endif

#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
    unsigned char *psk;             
    size_t         psk_len;         
    unsigned char *psk_identity;    
    size_t         psk_identity_len;
#endif

#if defined(MBEDTLS_SSL_ALPN)
    const char **alpn_list;         
#endif

    /*
     * Numerical settings (int then char)
     */

    uint32_t read_timeout;          
#if defined(MBEDTLS_SSL_PROTO_DTLS)
    uint32_t hs_timeout_min;        
    uint32_t hs_timeout_max;        
#endif

#if defined(MBEDTLS_SSL_RENEGOTIATION)
    int renego_max_records;         
    unsigned char renego_period[8]; 
#endif

#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
    unsigned int badmac_limit;      
#endif

#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
    unsigned int dhm_min_bitlen;    
#endif

    unsigned char max_major_ver;    
    unsigned char max_minor_ver;    
    unsigned char min_major_ver;    
    unsigned char min_minor_ver;    
    /*
     * Flags (bitfields)
     */

    unsigned int endpoint : 1;      
    unsigned int transport : 1;     
    unsigned int authmode : 2;      
    /* needed even with renego disabled for LEGACY_BREAK_HANDSHAKE          */
    unsigned int allow_legacy_renegotiation : 2 ; 
#if defined(MBEDTLS_ARC4_C)
    unsigned int arc4_disabled : 1; 
#endif
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
    unsigned int mfl_code : 3;      
#endif
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
    unsigned int encrypt_then_mac : 1 ; 
#endif
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
    unsigned int extended_ms : 1;   
#endif
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
    unsigned int anti_replay : 1;   
#endif
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
    unsigned int cbc_record_splitting : 1;  
#endif
#if defined(MBEDTLS_SSL_RENEGOTIATION)
    unsigned int disable_renegotiation : 1; 
#endif
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
    unsigned int trunc_hmac : 1;    
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
    unsigned int session_tickets : 1;   
#endif
#if defined(MBEDTLS_SSL_FALLBACK_SCSV) && defined(MBEDTLS_SSL_CLI_C)
    unsigned int fallback : 1;      
#endif
#if defined(MBEDTLS_SSL_SRV_C)
    unsigned int cert_req_ca_list : 1;  
#endif
};


struct mbedtls_ssl_context
{
    const mbedtls_ssl_config *conf; 
    /*
     * Miscellaneous
     */
    int state;                  
#if defined(MBEDTLS_SSL_RENEGOTIATION)
    int renego_status;          
    int renego_records_seen;    
#endif /* MBEDTLS_SSL_RENEGOTIATION */

    int major_ver;              
    int minor_ver;              
#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT)
    unsigned badmac_seen;       
#endif /* MBEDTLS_SSL_DTLS_BADMAC_LIMIT */

    mbedtls_ssl_send_t *f_send; 
    mbedtls_ssl_recv_t *f_recv; 
    mbedtls_ssl_recv_timeout_t *f_recv_timeout;
    void *p_bio;                
    /*
     * Session layer
     */
    mbedtls_ssl_session *session_in;            
    mbedtls_ssl_session *session_out;           
    mbedtls_ssl_session *session;               
    mbedtls_ssl_session *session_negotiate;     
    mbedtls_ssl_handshake_params *handshake;    
    /*
     * Record layer transformations
     */
    mbedtls_ssl_transform *transform_in;        
    mbedtls_ssl_transform *transform_out;       
    mbedtls_ssl_transform *transform;           
    mbedtls_ssl_transform *transform_negotiate; 
    /*
     * Timers
     */
    void *p_timer;              
    mbedtls_ssl_set_timer_t *f_set_timer;       
    mbedtls_ssl_get_timer_t *f_get_timer;       
    /*
     * Record layer (incoming data)
     */
    unsigned char *in_buf;      
    unsigned char *in_ctr;      
    unsigned char *in_hdr;      
    unsigned char *in_len;      
    unsigned char *in_iv;       
    unsigned char *in_msg;      
    unsigned char *in_offt;     
    int in_msgtype;             
    size_t in_msglen;           
    size_t in_left;             
#if defined(MBEDTLS_SSL_PROTO_DTLS)
    uint16_t in_epoch;          
    size_t next_record_offset;  
#endif /* MBEDTLS_SSL_PROTO_DTLS */
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
    uint64_t in_window_top;     
    uint64_t in_window;         
#endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */

    size_t in_hslen;            
    int nb_zero;                
    int keep_current_message;   
#if defined(MBEDTLS_SSL_PROTO_DTLS)
    uint8_t disable_datagram_packing;  
#endif /* MBEDTLS_SSL_PROTO_DTLS */

    /*
     * Record layer (outgoing data)
     */
    unsigned char *out_buf;     
    unsigned char *out_ctr;     
    unsigned char *out_hdr;     
    unsigned char *out_len;     
    unsigned char *out_iv;      
    unsigned char *out_msg;     
    int out_msgtype;            
    size_t out_msglen;          
    size_t out_left;            
    unsigned char cur_out_ctr[8]; 
#if defined(MBEDTLS_SSL_PROTO_DTLS)
    uint16_t mtu;               
#endif /* MBEDTLS_SSL_PROTO_DTLS */

#if defined(MBEDTLS_ZLIB_SUPPORT)
    unsigned char *compress_buf;        
#endif /* MBEDTLS_ZLIB_SUPPORT */
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
    signed char split_done;     
#endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */

    /*
     * PKI layer
     */
    int client_auth;                    
    /*
     * User settings
     */
#if defined(MBEDTLS_X509_CRT_PARSE_C)
    char *hostname;             
#endif /* MBEDTLS_X509_CRT_PARSE_C */

#if defined(MBEDTLS_SSL_ALPN)
    const char *alpn_chosen;    
#endif /* MBEDTLS_SSL_ALPN */

    /*
     * Information for DTLS hello verify
     */
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
    unsigned char  *cli_id;         
    size_t          cli_id_len;     
#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */

    /*
     * Secure renegotiation
     */
    /* needed to know when to send extension on server */
    int secure_renegotiation;           
#if defined(MBEDTLS_SSL_RENEGOTIATION)
    size_t verify_data_len;             
    char own_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; 
    char peer_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; 
#endif /* MBEDTLS_SSL_RENEGOTIATION */
};

#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 */

const char *mbedtls_ssl_get_ciphersuite_name( const int ciphersuite_id );

int mbedtls_ssl_get_ciphersuite_id( const char *ciphersuite_name );

void mbedtls_ssl_init( mbedtls_ssl_context *ssl );

int mbedtls_ssl_setup( mbedtls_ssl_context *ssl,
                       const mbedtls_ssl_config *conf );

int mbedtls_ssl_session_reset( mbedtls_ssl_context *ssl );

void mbedtls_ssl_conf_endpoint( mbedtls_ssl_config *conf, int endpoint );

void mbedtls_ssl_conf_transport( mbedtls_ssl_config *conf, int transport );

void mbedtls_ssl_conf_authmode( mbedtls_ssl_config *conf, int authmode );

#if defined(MBEDTLS_X509_CRT_PARSE_C)

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 */

void mbedtls_ssl_conf_rng( mbedtls_ssl_config *conf,
                  int (*f_rng)(void *, unsigned char *, size_t),
                  void *p_rng );

void mbedtls_ssl_conf_dbg( mbedtls_ssl_config *conf,
                  void (*f_dbg)(void *, int, const char *, int, const char *),
                  void  *p_dbg );

void mbedtls_ssl_set_bio( mbedtls_ssl_context *ssl,
                          void *p_bio,
                          mbedtls_ssl_send_t *f_send,
                          mbedtls_ssl_recv_t *f_recv,
                          mbedtls_ssl_recv_timeout_t *f_recv_timeout );

#if defined(MBEDTLS_SSL_PROTO_DTLS)

void mbedtls_ssl_set_mtu( mbedtls_ssl_context *ssl, uint16_t mtu );
#endif /* MBEDTLS_SSL_PROTO_DTLS */

void mbedtls_ssl_conf_read_timeout( mbedtls_ssl_config *conf, uint32_t timeout );

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 );

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)

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 */

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)

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)

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 */

#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)

void mbedtls_ssl_conf_async_private_cb( mbedtls_ssl_config *conf,
                                        mbedtls_ssl_async_sign_t *f_async_sign,
                                        mbedtls_ssl_async_decrypt_t *f_async_decrypt,
                                        mbedtls_ssl_async_resume_t *f_async_resume,
                                        mbedtls_ssl_async_cancel_t *f_async_cancel,
                                        void *config_data );

void *mbedtls_ssl_conf_get_async_config_data( const mbedtls_ssl_config *conf );

void *mbedtls_ssl_get_async_operation_data( const mbedtls_ssl_context *ssl );

void mbedtls_ssl_set_async_operation_data( mbedtls_ssl_context *ssl,
                                 void *ctx );
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */

typedef int mbedtls_ssl_cookie_write_t( void *ctx,
                                unsigned char **p, unsigned char *end,
                                const unsigned char *info, size_t ilen );

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)

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 );

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)

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)

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)

void mbedtls_ssl_set_datagram_packing( mbedtls_ssl_context *ssl,
                                       unsigned allow_packing );

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)

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)

int mbedtls_ssl_set_session( mbedtls_ssl_context *ssl, const mbedtls_ssl_session *session );
#endif /* MBEDTLS_SSL_CLI_C */

void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf,
                                   const int *ciphersuites );

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)

void mbedtls_ssl_conf_cert_profile( mbedtls_ssl_config *conf,
                                    const mbedtls_x509_crt_profile *profile );

void mbedtls_ssl_conf_ca_chain( mbedtls_ssl_config *conf,
                               mbedtls_x509_crt *ca_chain,
                               mbedtls_x509_crl *ca_crl );

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)

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 );


int mbedtls_ssl_set_hs_psk( mbedtls_ssl_context *ssl,
                            const unsigned char *psk, size_t psk_len );

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)

#if !defined(MBEDTLS_DEPRECATED_REMOVED)

#if defined(MBEDTLS_DEPRECATED_WARNING)
#define MBEDTLS_DEPRECATED    __attribute__((deprecated))
#else
#define MBEDTLS_DEPRECATED
#endif

MBEDTLS_DEPRECATED int mbedtls_ssl_conf_dh_param( mbedtls_ssl_config *conf,
                                                  const char *dhm_P,
                                                  const char *dhm_G );

#endif /* MBEDTLS_DEPRECATED_REMOVED */

int mbedtls_ssl_conf_dh_param_bin( mbedtls_ssl_config *conf,
                                   const unsigned char *dhm_P, size_t P_len,
                                   const unsigned char *dhm_G,  size_t G_len );

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)

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)

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)

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)

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)

int mbedtls_ssl_set_hs_own_cert( mbedtls_ssl_context *ssl,
                                 mbedtls_x509_crt *own_cert,
                                 mbedtls_pk_context *pk_key );

void mbedtls_ssl_set_hs_ca_chain( mbedtls_ssl_context *ssl,
                                  mbedtls_x509_crt *ca_chain,
                                  mbedtls_x509_crl *ca_crl );

void mbedtls_ssl_set_hs_authmode( mbedtls_ssl_context *ssl,
                                  int authmode );

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)

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)

int mbedtls_ssl_conf_alpn_protocols( mbedtls_ssl_config *conf, const char **protos );

const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl );
#endif /* MBEDTLS_SSL_ALPN */

void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor );

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)

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)

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)

void mbedtls_ssl_conf_extended_master_secret( mbedtls_ssl_config *conf, char ems );
#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */

#if defined(MBEDTLS_ARC4_C)

void mbedtls_ssl_conf_arc4_support( mbedtls_ssl_config *conf, char arc4 );
#endif /* MBEDTLS_ARC4_C */

#if defined(MBEDTLS_SSL_SRV_C)

void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf,
                                          char cert_req_ca_list );
#endif /* MBEDTLS_SSL_SRV_C */

#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)

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)

void mbedtls_ssl_conf_truncated_hmac( mbedtls_ssl_config *conf, int truncate );
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */

#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)

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)

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)

void mbedtls_ssl_conf_renegotiation( mbedtls_ssl_config *conf, int renegotiation );
#endif /* MBEDTLS_SSL_RENEGOTIATION */

void mbedtls_ssl_conf_legacy_renegotiation( mbedtls_ssl_config *conf, int allow_legacy );

#if defined(MBEDTLS_SSL_RENEGOTIATION)

void mbedtls_ssl_conf_renegotiation_enforced( mbedtls_ssl_config *conf, int max_records );

void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf,
                                   const unsigned char period[8] );
#endif /* MBEDTLS_SSL_RENEGOTIATION */

int mbedtls_ssl_check_pending( const mbedtls_ssl_context *ssl );

size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl );

uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl );

const char *mbedtls_ssl_get_ciphersuite( const mbedtls_ssl_context *ssl );

const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl );

int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl );

#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)

size_t mbedtls_ssl_get_max_frag_len( const mbedtls_ssl_context *ssl );
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */

int mbedtls_ssl_get_max_out_record_payload( const mbedtls_ssl_context *ssl );

#if defined(MBEDTLS_X509_CRT_PARSE_C)

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)

int mbedtls_ssl_get_session( const mbedtls_ssl_context *ssl, mbedtls_ssl_session *session );
#endif /* MBEDTLS_SSL_CLI_C */

int mbedtls_ssl_handshake( mbedtls_ssl_context *ssl );

int mbedtls_ssl_handshake_step( mbedtls_ssl_context *ssl );

#if defined(MBEDTLS_SSL_RENEGOTIATION)

int mbedtls_ssl_renegotiate( mbedtls_ssl_context *ssl );
#endif /* MBEDTLS_SSL_RENEGOTIATION */

int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len );

int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len );

int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl,
                            unsigned char level,
                            unsigned char message );
int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl );

void mbedtls_ssl_free( mbedtls_ssl_context *ssl );

void mbedtls_ssl_config_init( mbedtls_ssl_config *conf );

int mbedtls_ssl_config_defaults( mbedtls_ssl_config *conf,
                                 int endpoint, int transport, int preset );

void mbedtls_ssl_config_free( mbedtls_ssl_config *conf );

void mbedtls_ssl_session_init( mbedtls_ssl_session *session );

void mbedtls_ssl_session_free( mbedtls_ssl_session *session );

#ifdef __cplusplus
}
#endif

#endif /* ssl.h */