/**
* \file ssl.h
*
* \brief SSL/TLS functions.
*/
/*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: GPL-2.0
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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 /**< 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 /**< No data of requested type currently available on underlying transport. */
#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 */
#define MBEDTLS_ERR_SSL_CONTINUE_PROCESSING -0x6580 /**< Internal-only message signaling that further message-processing should be done */
#define MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS -0x6500 /**< The asynchronous operation is not completed yet. */
#define MBEDTLS_ERR_SSL_EARLY_MESSAGE -0x6480 /**< Internal-only message signaling that a message arrived early. */
#define MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS -0x7000 /**< A cryptographic operation is in progress. Try again later. */
/*
* 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
#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
/**
* \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
/*
* 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 /**< Size of the input / output buffer */
#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 /**< 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;
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)
/**
* \brief Callback type: start external signature operation.
*
* This callback is called during an SSL handshake to start
* a signature decryption operation using an
* external processor. The parameter \p cert contains
* the public key; it is up to the callback function to
* determine how to access the associated private key.
*
* This function typically sends or enqueues a request, and
* does not wait for the operation to complete. This allows
* the handshake step to be non-blocking.
*
* The parameters \p ssl and \p cert are guaranteed to remain
* valid throughout the handshake. On the other hand, this
* function must save the contents of \p hash if the value
* is needed for later processing, because the \p hash buffer
* is no longer valid after this function returns.
*
* This function may call mbedtls_ssl_set_async_operation_data()
* to store an operation context for later retrieval
* by the resume or cancel callback.
*
* \note For RSA signatures, this function must produce output
* that is consistent with PKCS#1 v1.5 in the same way as
* mbedtls_rsa_pkcs1_sign(). Before the private key operation,
* apply the padding steps described in RFC 8017, section 9.2
* "EMSA-PKCS1-v1_5" as follows.
* - If \p md_alg is #MBEDTLS_MD_NONE, apply the PKCS#1 v1.5
* encoding, treating \p hash as the DigestInfo to be
* padded. In other words, apply EMSA-PKCS1-v1_5 starting
* from step 3, with `T = hash` and `tLen = hash_len`.
* - If `md_alg != MBEDTLS_MD_NONE`, apply the PKCS#1 v1.5
* encoding, treating \p hash as the hash to be encoded and
* padded. In other words, apply EMSA-PKCS1-v1_5 starting
* from step 2, with `digestAlgorithm` obtained by calling
* mbedtls_oid_get_oid_by_md() on \p md_alg.
*
* \note For ECDSA signatures, the output format is the DER encoding
* `Ecdsa-Sig-Value` defined in
* [RFC 4492 section 5.4](https://tools.ietf.org/html/rfc4492#section-5.4).
*
* \param ssl The SSL connection instance. It should not be
* modified other than via
* mbedtls_ssl_set_async_operation_data().
* \param cert Certificate containing the public key.
* In simple cases, this is one of the pointers passed to
* mbedtls_ssl_conf_own_cert() when configuring the SSL
* connection. However, if other callbacks are used, this
* property may not hold. For example, if an SNI callback
* is registered with mbedtls_ssl_conf_sni(), then
* this callback determines what certificate is used.
* \param md_alg Hash algorithm.
* \param hash Buffer containing the hash. This buffer is
* no longer valid when the function returns.
* \param hash_len Size of the \c hash buffer in bytes.
*
* \return 0 if the operation was started successfully and the SSL
* stack should call the resume callback immediately.
* \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
* was started successfully and the SSL stack should return
* immediately without calling the resume callback yet.
* \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
* processor does not support this key. The SSL stack will
* use the private key object instead.
* \return Any other error indicates a fatal failure and is
* propagated up the call chain. The callback should
* use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
* use \c MBEDTLS_ERR_SSL_xxx error codes except as
* directed in the documentation of this callback.
*/
typedef int mbedtls_ssl_async_sign_t( mbedtls_ssl_context *ssl,
mbedtls_x509_crt *cert,
mbedtls_md_type_t md_alg,
const unsigned char *hash,
size_t hash_len );
/**
* \brief Callback type: start external decryption operation.
*
* This callback is called during an SSL handshake to start
* an RSA decryption operation using an
* external processor. The parameter \p cert contains
* the public key; it is up to the callback function to
* determine how to access the associated private key.
*
* This function typically sends or enqueues a request, and
* does not wait for the operation to complete. This allows
* the handshake step to be non-blocking.
*
* The parameters \p ssl and \p cert are guaranteed to remain
* valid throughout the handshake. On the other hand, this
* function must save the contents of \p input if the value
* is needed for later processing, because the \p input buffer
* is no longer valid after this function returns.
*
* This function may call mbedtls_ssl_set_async_operation_data()
* to store an operation context for later retrieval
* by the resume or cancel callback.
*
* \warning RSA decryption as used in TLS is subject to a potential
* timing side channel attack first discovered by Bleichenbacher
* in 1998. This attack can be remotely exploitable
* in practice. To avoid this attack, you must ensure that
* if the callback performs an RSA decryption, the time it
* takes to execute and return the result does not depend
* on whether the RSA decryption succeeded or reported
* invalid padding.
*
* \param ssl The SSL connection instance. It should not be
* modified other than via
* mbedtls_ssl_set_async_operation_data().
* \param cert Certificate containing the public key.
* In simple cases, this is one of the pointers passed to
* mbedtls_ssl_conf_own_cert() when configuring the SSL
* connection. However, if other callbacks are used, this
* property may not hold. For example, if an SNI callback
* is registered with mbedtls_ssl_conf_sni(), then
* this callback determines what certificate is used.
* \param input Buffer containing the input ciphertext. This buffer
* is no longer valid when the function returns.
* \param input_len Size of the \p input buffer in bytes.
*
* \return 0 if the operation was started successfully and the SSL
* stack should call the resume callback immediately.
* \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
* was started successfully and the SSL stack should return
* immediately without calling the resume callback yet.
* \return #MBEDTLS_ERR_SSL_HW_ACCEL_FALLTHROUGH if the external
* processor does not support this key. The SSL stack will
* use the private key object instead.
* \return Any other error indicates a fatal failure and is
* propagated up the call chain. The callback should
* use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
* use \c MBEDTLS_ERR_SSL_xxx error codes except as
* directed in the documentation of this callback.
*/
typedef int mbedtls_ssl_async_decrypt_t( mbedtls_ssl_context *ssl,
mbedtls_x509_crt *cert,
const unsigned char *input,
size_t input_len );
#endif /* MBEDTLS_X509_CRT_PARSE_C */
/**
* \brief Callback type: resume external operation.
*
* This callback is called during an SSL handshake to resume
* an external operation started by the
* ::mbedtls_ssl_async_sign_t or
* ::mbedtls_ssl_async_decrypt_t callback.
*
* This function typically checks the status of a pending
* request or causes the request queue to make progress, and
* does not wait for the operation to complete. This allows
* the handshake step to be non-blocking.
*
* This function may call mbedtls_ssl_get_async_operation_data()
* to retrieve an operation context set by the start callback.
* It may call mbedtls_ssl_set_async_operation_data() to modify
* this context.
*
* Note that when this function returns a status other than
* #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, it must free any
* resources associated with the operation.
*
* \param ssl The SSL connection instance. It should not be
* modified other than via
* mbedtls_ssl_set_async_operation_data().
* \param output Buffer containing the output (signature or decrypted
* data) on success.
* \param output_len On success, number of bytes written to \p output.
* \param output_size Size of the \p output buffer in bytes.
*
* \return 0 if output of the operation is available in the
* \p output buffer.
* \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if the operation
* is still in progress. Subsequent requests for progress
* on the SSL connection will call the resume callback
* again.
* \return Any other error means that the operation is aborted.
* The SSL handshake is aborted. The callback should
* use \c MBEDTLS_ERR_PK_xxx error codes, and <b>must not</b>
* use \c MBEDTLS_ERR_SSL_xxx error codes except as
* directed in the documentation of this callback.
*/
typedef int mbedtls_ssl_async_resume_t( mbedtls_ssl_context *ssl,
unsigned char *output,
size_t *output_len,
size_t output_size );
/**
* \brief Callback type: cancel external operation.
*
* This callback is called if an SSL connection is closed
* while an asynchronous operation is in progress. Note that
* this callback is not called if the
* ::mbedtls_ssl_async_resume_t callback has run and has
* returned a value other than
* #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS, since in that case
* the asynchronous operation has already completed.
*
* This function may call mbedtls_ssl_get_async_operation_data()
* to retrieve an operation context set by the start callback.
*
* \param ssl The SSL connection instance. It should not be
* modified.
*/
typedef void mbedtls_ssl_async_cancel_t( mbedtls_ssl_context *ssl );
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
/*
* 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_SSL_ASYNC_PRIVATE)
#if defined(MBEDTLS_X509_CRT_PARSE_C)
mbedtls_ssl_async_sign_t *f_async_sign_start; /*!< start asynchronous signature operation */
mbedtls_ssl_async_decrypt_t *f_async_decrypt_start; /*!< start asynchronous decryption operation */
#endif /* MBEDTLS_X509_CRT_PARSE_C */
mbedtls_ssl_async_resume_t *f_async_resume; /*!< resume asynchronous operation */
mbedtls_ssl_async_cancel_t *f_async_cancel; /*!< cancel asynchronous operation */
void *p_async_config_data; /*!< Configuration data set by mbedtls_ssl_conf_async_private_cb(). */
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
#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. This field should
only be set via
mbedtls_ssl_conf_psk() */
size_t psk_len; /*!< length of the pre-shared key. This
field should only be set via
mbedtls_ssl_conf_psk() */
unsigned char *psk_identity; /*!< identity for PSK negotiation. This
field should only be set via
mbedtls_ssl_conf_psk() */
size_t psk_identity_len;/*!< length of identity. This field should
only be set via
mbedtls_ssl_conf_psk() */
#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
#if defined(MBEDTLS_SSL_SRV_C)
unsigned int cert_req_ca_list : 1; /*!< enable sending CA list in
Certificate Request messages? */
#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 /* MBEDTLS_SSL_RENEGOTIATION */
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_DTLS_BADMAC_LIMIT */
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 /* MBEDTLS_SSL_PROTO_DTLS */
#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 /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
size_t in_hslen; /*!< current handshake message length,
including the handshake header */
int nb_zero; /*!< # of 0-length encrypted messages */
int keep_current_message; /*!< drop or reuse current message
on next call to record layer? */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
uint8_t disable_datagram_packing; /*!< Disable packing multiple records
* within a single datagram. */
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/*
* 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 */
unsigned char cur_out_ctr[8]; /*!< Outgoing record sequence number. */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
uint16_t mtu; /*!< path mtu, used to fragment outgoing messages */
#endif /* MBEDTLS_SSL_PROTO_DTLS */
#if defined(MBEDTLS_ZLIB_SUPPORT)
unsigned char *compress_buf; /*!< zlib data buffer */
#endif /* MBEDTLS_ZLIB_SUPPORT */
#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
signed char split_done; /*!< current record already splitted? */
#endif /* MBEDTLS_SSL_CBC_RECORD_SPLITTING */
/*
* 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 /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_ALPN)
const char *alpn_chosen; /*!< negotiated protocol */
#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; /*!< transport-level ID of the client */
size_t cli_id_len; /*!< length of cli_id */
#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
/*
* Secure renegotiation
*/
/* needed to know when to send extension on server */
int 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 /* 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 */
/**
* \brief Return the name of the ciphersuite associated with the
* given ID
*
* \param ciphersuite_id SSL ciphersuite ID
*
* \return a string containing the ciphersuite name
*/
const char *mbedtls_ssl_get_ciphersuite_name( const int ciphersuite_id );
/**
* \brief Return the ID of the ciphersuite associated with the
* given name
*
* \param ciphersuite_name SSL ciphersuite name
*
* \return the ID with the ciphersuite or 0 if not found
*/
int mbedtls_ssl_get_ciphersuite_id( const char *ciphersuite_name );
/**
* \brief Initialize an SSL context
* Just makes the context ready for mbedtls_ssl_setup() or
* mbedtls_ssl_free()
*
* \param ssl SSL context
*/
void mbedtls_ssl_init( mbedtls_ssl_context *ssl );
/**
* \brief Set up an SSL context for use
*
* \note No copy of the configuration context is made, it can be
* shared by many mbedtls_ssl_context structures.
*
* \warning The conf structure will be accessed during the session.
* It must not be modified or freed as long as the session
* is active.
*
* \warning This function must be called exactly once per context.
* Calling mbedtls_ssl_setup again is not supported, even
* if no session is active.
*
* \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 mbedtls_x509_crt_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 );
#if defined(MBEDTLS_SSL_PROTO_DTLS)
/**
* \brief Set the Maximum Tranport Unit (MTU).
* Special value: 0 means unset (no limit).
* This represents the maximum size of a datagram payload
* handled by the transport layer (usually UDP) as determined
* by the network link and stack. In practice, this controls
* the maximum size datagram the DTLS layer will pass to the
* \c f_send() callback set using \c mbedtls_ssl_set_bio().
*
* \note The limit on datagram size is converted to a limit on
* record payload by subtracting the current overhead of
* encapsulation and encryption/authentication if any.
*
* \note This can be called at any point during the connection, for
* example when a Path Maximum Transfer Unit (PMTU)
* estimate becomes available from other sources,
* such as lower (or higher) protocol layers.
*
* \note This setting only controls the size of the packets we send,
* and does not restrict the size of the datagrams we're
* willing to receive. Client-side, you can request the
* server to use smaller records with \c
* mbedtls_ssl_conf_max_frag_len().
*
* \note If both a MTU and a maximum fragment length have been
* configured (or negotiated with the peer), the resulting
* lower limit on record payload (see first note) is used.
*
* \note This can only be used to decrease the maximum size
* of datagrams (hence records, see first note) sent. It
* cannot be used to increase the maximum size of records over
* the limit set by #MBEDTLS_SSL_OUT_CONTENT_LEN.
*
* \note Values lower than the current record layer expansion will
* result in an error when trying to send data.
*
* \note Using record compression together with a non-zero MTU value
* will result in an error when trying to send data.
*
* \param ssl SSL context
* \param mtu Value of the path MTU in bytes
*/
void mbedtls_ssl_set_mtu( mbedtls_ssl_context *ssl, uint16_t mtu );
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/**
* \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 follow.
*
* \note On some platforms, timing.c provides
* \c mbedtls_timing_set_delay() and
* \c mbedtls_timing_get_delay() that are suitable for using
* here, except if using an event-driven style.
*
* \note See also the "DTLS tutorial" article in our knowledge base.
* https://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 */
#if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
/**
* \brief Configure asynchronous private key operation callbacks.
*
* \param conf SSL configuration context
* \param f_async_sign Callback to start a signature operation. See
* the description of ::mbedtls_ssl_async_sign_t
* for more information. This may be \c NULL if the
* external processor does not support any signature
* operation; in this case the private key object
* associated with the certificate will be used.
* \param f_async_decrypt Callback to start a decryption operation. See
* the description of ::mbedtls_ssl_async_decrypt_t
* for more information. This may be \c NULL if the
* external processor does not support any decryption
* operation; in this case the private key object
* associated with the certificate will be used.
* \param f_async_resume Callback to resume an asynchronous operation. See
* the description of ::mbedtls_ssl_async_resume_t
* for more information. This may not be \c NULL unless
* \p f_async_sign and \p f_async_decrypt are both
* \c NULL.
* \param f_async_cancel Callback to cancel an asynchronous operation. See
* the description of ::mbedtls_ssl_async_cancel_t
* for more information. This may be \c NULL if
* no cleanup is needed.
* \param config_data A pointer to configuration data which can be
* retrieved with
* mbedtls_ssl_conf_get_async_config_data(). The
* library stores this value without dereferencing it.
*/
void mbedtls_ssl_conf_async_private_cb( mbedtls_ssl_config *conf,
mbedtls_ssl_async_sign_t *f_async_sign,
mbedtls_ssl_async_decrypt_t *f_async_decrypt,
mbedtls_ssl_async_resume_t *f_async_resume,
mbedtls_ssl_async_cancel_t *f_async_cancel,
void *config_data );
/**
* \brief Retrieve the configuration data set by
* mbedtls_ssl_conf_async_private_cb().
*
* \param conf SSL configuration context
* \return The configuration data set by
* mbedtls_ssl_conf_async_private_cb().
*/
void *mbedtls_ssl_conf_get_async_config_data( const mbedtls_ssl_config *conf );
/**
* \brief Retrieve the asynchronous operation user context.
*
* \note This function may only be called while a handshake
* is in progress.
*
* \param ssl The SSL context to access.
*
* \return The asynchronous operation user context that was last
* set during the current handshake. If
* mbedtls_ssl_set_async_operation_data() has not yet been
* called during the current handshake, this function returns
* \c NULL.
*/
void *mbedtls_ssl_get_async_operation_data( const mbedtls_ssl_context *ssl );
/**
* \brief Retrieve the asynchronous operation user context.
*
* \note This function may only be called while a handshake
* is in progress.
*
* \param ssl The SSL context to access.
* \param ctx The new value of the asynchronous operation user context.
* Call mbedtls_ssl_get_async_operation_data() later during the
* same handshake to retrieve this value.
*/
void mbedtls_ssl_set_async_operation_data( mbedtls_ssl_context *ssl,
void *ctx );
#endif /* MBEDTLS_SSL_ASYNC_PRIVATE */
/**
* \brief Callback type: generate a cookie
*
* \param ctx Context for the callback
* \param p Buffer to write to,
* must be updated to point right after the cookie
* \param end Pointer to one past the end of the output buffer
* \param info Client ID info that was passed to
* \c mbedtls_ssl_set_client_transport_id()
* \param ilen Length of info in bytes
*
* \return The callback must return 0 on success,
* or a negative error code.
*/
typedef int mbedtls_ssl_cookie_write_t( void *ctx,
unsigned char **p, unsigned char *end,
const unsigned char *info, size_t ilen );
/**
* \brief Callback type: verify a cookie
*
* \param ctx Context for the callback
* \param cookie Cookie to verify
* \param clen Length of cookie
* \param info Client ID info that was passed to
* \c mbedtls_ssl_set_client_transport_id()
* \param ilen Length of info in bytes
*
* \return The callback must return 0 if cookie is valid,
* or a negative error code.
*/
typedef int mbedtls_ssl_cookie_check_t( void *ctx,
const unsigned char *cookie, size_t clen,
const unsigned char *info, size_t ilen );
#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
/**
* \brief Register callbacks for DTLS cookies
* (Server only. DTLS only.)
*
* Default: dummy callbacks that fail, in order to force you to
* register working callbacks (and initialize their context).
*
* To disable HelloVerifyRequest, register NULL callbacks.
*
* \warning Disabling hello verification allows your server to be used
* for amplification in DoS attacks against other hosts.
* Only disable if you known this can't happen in your
* particular environment.
*
* \note See comments on \c mbedtls_ssl_handshake() about handling
* the MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED that is expected
* on the first handshake attempt when this is enabled.
*
* \note This is also necessary to handle client reconnection from
* the same port as described in RFC 6347 section 4.2.8 (only
* the variant with cookies is supported currently). See
* comments on \c mbedtls_ssl_read() for details.
*
* \param conf SSL configuration
* \param f_cookie_write Cookie write callback
* \param f_cookie_check Cookie check callback
* \param p_cookie Context for both callbacks
*/
void mbedtls_ssl_conf_dtls_cookies( mbedtls_ssl_config *conf,
mbedtls_ssl_cookie_write_t *f_cookie_write,
mbedtls_ssl_cookie_check_t *f_cookie_check,
void *p_cookie );
/**
* \brief Set client's transport-level identification info.
* (Server only. DTLS only.)
*
* This is usually the IP address (and port), but could be
* anything identify the client depending on the underlying
* network stack. Used for HelloVerifyRequest with DTLS.
* This is *not* used to route the actual packets.
*
* \param ssl SSL context
* \param info Transport-level info identifying the client (eg IP + port)
* \param ilen Length of info in bytes
*
* \note An internal copy is made, so the info buffer can be reused.
*
* \return 0 on success,
* MBEDTLS_ERR_SSL_BAD_INPUT_DATA if used on client,
* MBEDTLS_ERR_SSL_ALLOC_FAILED if out of memory.
*/
int mbedtls_ssl_set_client_transport_id( mbedtls_ssl_context *ssl,
const unsigned char *info,
size_t ilen );
#endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY && MBEDTLS_SSL_SRV_C */
#if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
/**
* \brief Enable or disable anti-replay protection for DTLS.
* (DTLS only, no effect on TLS.)
* Default: enabled.
*
* \param conf SSL configuration
* \param mode MBEDTLS_SSL_ANTI_REPLAY_ENABLED or MBEDTLS_SSL_ANTI_REPLAY_DISABLED.
*
* \warning Disabling this is a security risk unless the application
* protocol handles duplicated packets in a safe way. You
* should not disable this without careful consideration.
* However, if your application already detects duplicated
* packets and needs information about them to adjust its
* transmission strategy, then you'll want to disable this.
*/
void mbedtls_ssl_conf_dtls_anti_replay( mbedtls_ssl_config *conf, char mode );
#endif /* MBEDTLS_SSL_DTLS_ANTI_REPLAY */
#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 Allow or disallow packing of multiple handshake records
* within a single datagram.
*
* \param ssl The SSL context to configure.
* \param allow_packing This determines whether datagram packing may
* be used or not. A value of \c 0 means that every
* record will be sent in a separate datagram; a
* value of \c 1 means that, if space permits,
* multiple handshake messages (including CCS) belonging to
* a single flight may be packed within a single datagram.
*
* \note This is enabled by default and should only be disabled
* for test purposes, or if datagram packing causes
* interoperability issues with peers that don't support it.
*
* \note Allowing datagram packing reduces the network load since
* there's less overhead if multiple messages share the same
* datagram. Also, it increases the handshake efficiency
* since messages belonging to a single datagram will not
* be reordered in transit, and so future message buffering
* or flight retransmission (if no buffering is used) as
* means to deal with reordering are needed less frequently.
*
* \note Application records are not affected by this option and
* are currently always sent in separate datagrams.
*
*/
void mbedtls_ssl_set_datagram_packing( mbedtls_ssl_context *ssl,
unsigned allow_packing );
/**
* \brief Set retransmit timeout values for the DTLS handshake.
* (DTLS only, no effect on TLS.)
*
* \param conf SSL configuration
* \param min Initial timeout value in milliseconds.
* Default: 1000 (1 second).
* \param max Maximum timeout value in milliseconds.
* Default: 60000 (60 seconds).
*
* \note Default values are from RFC 6347 section 4.2.4.1.
*
* \note The 'min' value should typically be slightly above the
* expected round-trip time to your peer, plus whatever time
* it takes for the peer to process the message. For example,
* if your RTT is about 600ms and you peer needs up to 1s to
* do the cryptographic operations in the handshake, then you
* should set 'min' slightly above 1600. Lower values of 'min'
* might cause spurious resends which waste network resources,
* while larger value of 'min' will increase overall latency
* on unreliable network links.
*
* \note The more unreliable your network connection is, the larger
* your max / min ratio needs to be in order to achieve
* reliable handshakes.
*
* \note Messages are retransmitted up to log2(ceil(max/min)) times.
* For example, if min = 1s and max = 5s, the retransmit plan
* goes: send ... 1s -> resend ... 2s -> resend ... 4s ->
* resend ... 5s -> give up and return a timeout error.
*/
void mbedtls_ssl_conf_handshake_timeout( mbedtls_ssl_config *conf, uint32_t min, uint32_t max );
#endif /* MBEDTLS_SSL_PROTO_DTLS */
#if defined(MBEDTLS_SSL_SRV_C)
/**
* \brief Set the session cache callbacks (server-side only)
* If not set, no session resuming is done (except if session
* tickets are enabled too).
*
* The session cache has the responsibility to check for stale
* entries based on timeout. See RFC 5246 for recommendations.
*
* Warning: session.peer_cert is cleared by the SSL/TLS layer on
* connection shutdown, so do not cache the pointer! Either set
* it to NULL or make a full copy of the certificate.
*
* The get callback is called once during the initial handshake
* to enable session resuming. The get function has the
* following parameters: (void *parameter, mbedtls_ssl_session *session)
* If a valid entry is found, it should fill the master of
* the session object with the cached values and return 0,
* return 1 otherwise. Optionally peer_cert can be set as well
* if it is properly present in cache entry.
*
* The set callback is called once during the initial handshake
* to enable session resuming after the entire handshake has
* been finished. The set function has the following parameters:
* (void *parameter, const mbedtls_ssl_session *session). The function
* should create a cache entry for future retrieval based on
* the data in the session structure and should keep in mind
* that the mbedtls_ssl_session object presented (and all its referenced
* data) is cleared by the SSL/TLS layer when the connection is
* terminated. It is recommended to add metadata to determine if
* an entry is still valid in the future. Return 0 if
* successfully cached, return 1 otherwise.
*
* \param conf SSL configuration
* \param p_cache 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
*
* \note See \c mbedtls_x509_crt_verify() for notes regarding the
* parameters ca_chain (maps to trust_ca for that function)
* and ca_crl.
*
* \param conf SSL configuration
* \param ca_chain trusted CA chain (meaning all fully trusted top-level CAs)
* \param ca_crl trusted CA CRLs
*/
void mbedtls_ssl_conf_ca_chain( mbedtls_ssl_config *conf,
mbedtls_x509_crt *ca_chain,
mbedtls_x509_crl *ca_crl );
/**
* \brief Set own certificate chain and private key
*
* \note own_cert should contain in order from the bottom up your
* certificate chain. The top certificate (self-signed)
* can be omitted.
*
* \note On server, this function can be called multiple times to
* provision more than one cert/key pair (eg one ECDSA, one
* RSA with SHA-256, one RSA with SHA-1). An adequate
* certificate will be selected according to the client's
* advertised capabilities. In case multiple certificates are
* adequate, preference is given to the one set by the first
* call to this function, then second, etc.
*
* \note On client, only the first call has any effect. That is,
* only one client certificate can be provisioned. The
* server's preferences in its 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.
*
* \note The provided \p pk_key needs to match the public key in the
* first certificate in \p own_cert, or all handshakes using
* that certificate will fail. It is your responsibility
* to ensure that; this function will not perform any check.
* You may use mbedtls_pk_check_pair() in order to perform
* this check yourself, but be aware that this function can
* be computationally expensive on some key types.
*
* \param conf SSL configuration
* \param own_cert own public certificate chain
* \param pk_key own private key
*
* \return 0 on success or MBEDTLS_ERR_SSL_ALLOC_FAILED
*/
int mbedtls_ssl_conf_own_cert( mbedtls_ssl_config *conf,
mbedtls_x509_crt *own_cert,
mbedtls_pk_context *pk_key );
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_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)
#if !defined(MBEDTLS_DEPRECATED_REMOVED)
#if defined(MBEDTLS_DEPRECATED_WARNING)
#define MBEDTLS_DEPRECATED __attribute__((deprecated))
#else
#define MBEDTLS_DEPRECATED
#endif
/**
* \brief Set the Diffie-Hellman public P and G values,
* read as hexadecimal strings (server-side only)
* (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG])
*
* \param conf SSL configuration
* \param dhm_P Diffie-Hellman-Merkle modulus
* \param dhm_G Diffie-Hellman-Merkle generator
*
* \deprecated Superseded by \c mbedtls_ssl_conf_dh_param_bin.
*
* \return 0 if successful
*/
MBEDTLS_DEPRECATED int mbedtls_ssl_conf_dh_param( mbedtls_ssl_config *conf,
const char *dhm_P,
const char *dhm_G );
#endif /* MBEDTLS_DEPRECATED_REMOVED */
/**
* \brief Set the Diffie-Hellman public P and G values
* from big-endian binary presentations.
* (Default values: MBEDTLS_DHM_RFC3526_MODP_2048_[PG]_BIN)
*
* \param conf SSL configuration
* \param dhm_P Diffie-Hellman-Merkle modulus in big-endian binary form
* \param P_len Length of DHM modulus
* \param dhm_G Diffie-Hellman-Merkle generator in big-endian binary form
* \param G_len Length of DHM generator
*
* \return 0 if successful
*/
int mbedtls_ssl_conf_dh_param_bin( mbedtls_ssl_config *conf,
const unsigned char *dhm_P, size_t P_len,
const unsigned char *dhm_G, size_t G_len );
/**
* \brief Set the Diffie-Hellman public P and G values,
* read from existing context (server-side only)
*
* \param conf SSL configuration
* \param dhm_ctx Diffie-Hellman-Merkle context
*
* \return 0 if successful
*/
int mbedtls_ssl_conf_dh_param_ctx( mbedtls_ssl_config *conf, mbedtls_dhm_context *dhm_ctx );
#endif /* MBEDTLS_DHM_C && defined(MBEDTLS_SSL_SRV_C) */
#if defined(MBEDTLS_DHM_C) && defined(MBEDTLS_SSL_CLI_C)
/**
* \brief Set the minimum length for Diffie-Hellman parameters.
* (Client-side only.)
* (Default: 1024 bits.)
*
* \param conf SSL configuration
* \param bitlen Minimum bit length of the DHM prime
*/
void mbedtls_ssl_conf_dhm_min_bitlen( mbedtls_ssl_config *conf,
unsigned int bitlen );
#endif /* MBEDTLS_DHM_C && MBEDTLS_SSL_CLI_C */
#if defined(MBEDTLS_ECP_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 or reset the hostname to check against the received
* server certificate. It sets the ServerName TLS extension,
* too, if that extension is enabled. (client-side only)
*
* \param ssl SSL context
* \param hostname the server hostname, may be NULL to clear hostname
* \note Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN.
*
* \return 0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on
* allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on
* too long input hostname.
*
* Hostname set to the one provided on success (cleared
* when NULL). On allocation failure hostname is cleared.
* On too long input failure, old hostname is unchanged.
*/
int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname );
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
/**
* \brief 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_SRV_C)
/**
* \brief Whether to send a list of acceptable CAs in
* CertificateRequest messages.
* (Default: do send)
*
* \param conf SSL configuration
* \param cert_req_ca_list MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED or
* MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED
*/
void mbedtls_ssl_conf_cert_req_ca_list( mbedtls_ssl_config *conf,
char cert_req_ca_list );
#endif /* MBEDTLS_SSL_SRV_C */
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
/**
* \brief Set the maximum fragment length to emit and/or negotiate.
* (Typical: the smaller of #MBEDTLS_SSL_IN_CONTENT_LEN and
* #MBEDTLS_SSL_OUT_CONTENT_LEN, usually `2^14` bytes)
* (Server: set maximum fragment length to emit,
* usually negotiated by the client during handshake)
* (Client: set maximum fragment length to emit *and*
* negotiate with the server during handshake)
* (Default: #MBEDTLS_SSL_MAX_FRAG_LEN_NONE)
*
* \note On the client side, the maximum fragment length extension
* *will not* be used, unless the maximum fragment length has
* been set via this function to a value different than
* #MBEDTLS_SSL_MAX_FRAG_LEN_NONE.
*
* \note This sets the maximum length for a record's payload,
* excluding record overhead that will be added to it, see
* \c mbedtls_ssl_get_record_expansion().
*
* \note With TLS, this currently only affects ApplicationData (sent
* with \c mbedtls_ssl_read()), not handshake messages.
* With DTLS, this affects both ApplicationData and handshake.
*
* \note For DTLS, it is also possible to set a limit for the total
* size of daragrams passed to the transport layer, including
* record overhead, see \c mbedtls_ssl_set_mtu().
*
* \param conf SSL configuration
* \param mfl_code Code for maximum fragment length (allowed values:
* MBEDTLS_SSL_MAX_FRAG_LEN_512, MBEDTLS_SSL_MAX_FRAG_LEN_1024,
* MBEDTLS_SSL_MAX_FRAG_LEN_2048, MBEDTLS_SSL_MAX_FRAG_LEN_4096)
*
* \return 0 if successful or MBEDTLS_ERR_SSL_BAD_INPUT_DATA
*/
int mbedtls_ssl_conf_max_frag_len( mbedtls_ssl_config *conf, unsigned char mfl_code );
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_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: 2^48 - 1)
*
* 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".
*
* The renegotiation period can be disabled by setting
* conf->disable_renegotiation to
* MBEDTLS_SSL_RENEGOTIATION_DISABLED.
*
* \note When the configured transport is
* MBEDTLS_SSL_TRANSPORT_DATAGRAM the maximum renegotiation
* period is 2^48 - 1, and for MBEDTLS_SSL_TRANSPORT_STREAM,
* the maximum renegotiation period is 2^64 - 1.
*
* \param conf SSL configuration
* \param period The threshold value: a big-endian 64-bit number.
*/
void mbedtls_ssl_conf_renegotiation_period( mbedtls_ssl_config *conf,
const unsigned char period[8] );
#endif /* MBEDTLS_SSL_RENEGOTIATION */
/**
* \brief Check if there is data already read from the
* underlying transport but not yet processed.
*
* \param ssl SSL context
*
* \return 0 if nothing's pending, 1 otherwise.
*
* \note This is different in purpose and behaviour from
* \c mbedtls_ssl_get_bytes_avail in that it considers
* any kind of unprocessed data, not only unread
* application data. If \c mbedtls_ssl_get_bytes
* returns a non-zero value, this function will
* also signal pending data, but the converse does
* not hold. For example, in DTLS there might be
* further records waiting to be processed from
* the current underlying transport's datagram.
*
* \note If this function returns 1 (data pending), this
* does not imply that a subsequent call to
* \c mbedtls_ssl_read will provide any data;
* e.g., the unprocessed data might turn out
* to be an alert or a handshake message.
*
* \note This function is useful in the following situation:
* If the SSL/TLS module successfully returns from an
* operation - e.g. a handshake or an application record
* read - and you're awaiting incoming data next, you
* must not immediately idle on the underlying transport
* to have data ready, but you need to check the value
* of this function first. The reason is that the desired
* data might already be read but not yet processed.
* If, in contrast, a previous call to the SSL/TLS module
* returned MBEDTLS_ERR_SSL_WANT_READ, it is not necessary
* to call this function, as the latter error code entails
* that all internal data has been processed.
*
*/
int mbedtls_ssl_check_pending( const mbedtls_ssl_context *ssl );
/**
* \brief Return the number of application data bytes
* remaining to be read from the current record.
*
* \param ssl SSL context
*
* \return How many bytes are available in the application
* data record read buffer.
*
* \note When working over a datagram transport, this is
* useful to detect the current datagram's boundary
* in case \c mbedtls_ssl_read has written the maximal
* amount of data fitting into the input buffer.
*
*/
size_t mbedtls_ssl_get_bytes_avail( const mbedtls_ssl_context *ssl );
/**
* \brief Return the result of the certificate verification
*
* \param ssl The SSL context to use.
*
* \return \c 0 if the certificate verification was successful.
* \return \c -1u if the result is not available. This may happen
* e.g. if the handshake aborts early, or a verification
* callback returned a fatal error.
* \return A bitwise combination of \c MBEDTLS_X509_BADCERT_XXX
* and \c MBEDTLS_X509_BADCRL_XXX failure flags; see x509.h.
*/
uint32_t mbedtls_ssl_get_verify_result( const mbedtls_ssl_context *ssl );
/**
* \brief Return the 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)
*
* \note This function is not available (always returns an error)
* when record compression is enabled.
*
* \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.
*
* \sa mbedtls_ssl_conf_max_frag_len()
* \sa mbedtls_ssl_get_max_record_payload()
*
* \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 */
/**
* \brief Return the current maximum outgoing record payload in bytes.
* This takes into account the config.h setting \c
* MBEDTLS_SSL_OUT_CONTENT_LEN, the configured and negotiated
* max fragment length extension if used, and for DTLS the
* path MTU as configured and current record expansion.
*
* \note With DTLS, \c mbedtls_ssl_write() will return an error if
* called with a larger length value.
* With TLS, \c mbedtls_ssl_write() will fragment the input if
* necessary and return the number of bytes written; it is up
* to the caller to call \c mbedtls_ssl_write() again in
* order to send the remaining bytes if any.
*
* \note This function is not available (always returns an error)
* when record compression is enabled.
*
* \sa mbedtls_ssl_set_mtu()
* \sa mbedtls_ssl_get_max_frag_len()
* \sa mbedtls_ssl_get_record_expansion()
*
* \param ssl SSL context
*
* \return Current maximum payload for an outgoing record,
* or a negative error code.
*/
int mbedtls_ssl_get_max_out_record_payload( const mbedtls_ssl_context *ssl );
#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.
*
*
* \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.
*
* \note Only the server certificate is copied, and not the full chain,
* so you should not attempt to validate the certificate again
* by calling \c mbedtls_x509_crt_verify() on it.
* Instead, you should use the results from the verification
* in the original handshake by calling \c mbedtls_ssl_get_verify_result()
* after loading the session again into a new SSL context
* using \c mbedtls_ssl_set_session().
*
* \note Once the session object is not needed anymore, you should
* free it by calling \c mbedtls_ssl_session_free().
*
* \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 \c 0 if successful.
* \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
* if the handshake is incomplete and waiting for data to
* be available for reading from or writing to the underlying
* transport - in this case you must call this function again
* when the underlying transport is ready for the operation.
* \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
* operation is in progress (see
* mbedtls_ssl_conf_async_private_cb()) - in this case you
* must call this function again when the operation is ready.
* \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
* operation is in progress (see mbedtls_ecp_set_max_ops()) -
* in this case you must call this function again to complete
* the handshake when you're done attending other tasks.
* \return #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED if DTLS is in use
* and the client did not demonstrate reachability yet - in
* this case you must stop using the context (see below).
* \return Another SSL error code - in this case you must stop using
* the context (see below).
*
* \warning If this function returns something other than
* \c 0,
* #MBEDTLS_ERR_SSL_WANT_READ,
* #MBEDTLS_ERR_SSL_WANT_WRITE,
* #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
* #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
* you must stop using the SSL context for reading or writing,
* and either free it or call \c mbedtls_ssl_session_reset()
* on it before re-using it for a new connection; the current
* connection must be closed.
*
* \note If DTLS is in use, then you may choose to handle
* #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED specially for logging
* purposes, as it is an expected return value rather than an
* actual error, but you still need to reset/free the context.
*
* \note Remarks regarding event-driven DTLS:
* If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
* from the underlying transport layer is currently being processed,
* and it is safe to idle until the timer or the underlying transport
* signal a new event. This is not true for a successful handshake,
* in which case the datagram of the underlying transport that is
* currently being processed might or might not contain further
* DTLS records.
*/
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 this function returns \c 0. Do not
* call this function if state is MBEDTLS_SSL_HANDSHAKE_OVER.
*
* \param ssl SSL context
*
* \return See mbedtls_ssl_handshake().
*
* \warning If this function returns something other than \c 0,
* #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
* #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
* #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
* the SSL context for reading or writing, and either free it
* or call \c mbedtls_ssl_session_reset() on it before
* re-using it for a new connection; the current connection
* must be closed.
*/
int mbedtls_ssl_handshake_step( mbedtls_ssl_context *ssl );
#if defined(MBEDTLS_SSL_RENEGOTIATION)
/**
* \brief Initiate an SSL renegotiation on the running connection.
* Client: perform the renegotiation right now.
* Server: request renegotiation, which will be performed
* during the next call to mbedtls_ssl_read() if honored by
* client.
*
* \param ssl SSL context
*
* \return 0 if successful, or any mbedtls_ssl_handshake() return
* value except #MBEDTLS_ERR_SSL_CLIENT_RECONNECT that can't
* happen during a renegotiation.
*
* \warning If this function returns something other than \c 0,
* #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
* #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
* #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
* the SSL context for reading or writing, and either free it
* or call \c mbedtls_ssl_session_reset() on it before
* re-using it for a new connection; the current connection
* must be closed.
*
*/
int mbedtls_ssl_renegotiate( mbedtls_ssl_context *ssl );
#endif /* MBEDTLS_SSL_RENEGOTIATION */
/**
* \brief Read at most 'len' application data bytes
*
* \param ssl SSL context
* \param buf buffer that will hold the data
* \param len maximum number of bytes to read
*
* \return The (positive) number of bytes read if successful.
* \return \c 0 if the read end of the underlying transport was closed
* - in this case you must stop using the context (see below).
* \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
* if the handshake is incomplete and waiting for data to
* be available for reading from or writing to the underlying
* transport - in this case you must call this function again
* when the underlying transport is ready for the operation.
* \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
* operation is in progress (see
* mbedtls_ssl_conf_async_private_cb()) - in this case you
* must call this function again when the operation is ready.
* \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
* operation is in progress (see mbedtls_ecp_set_max_ops()) -
* in this case you must call this function again to complete
* the handshake when you're done attending other tasks.
* \return #MBEDTLS_ERR_SSL_CLIENT_RECONNECT if we're at the server
* side of a DTLS connection and the client is initiating a
* new connection using the same source port. See below.
* \return Another SSL error code - in this case you must stop using
* the context (see below).
*
* \warning If this function returns something other than
* a positive value,
* #MBEDTLS_ERR_SSL_WANT_READ,
* #MBEDTLS_ERR_SSL_WANT_WRITE,
* #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
* #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
* #MBEDTLS_ERR_SSL_CLIENT_RECONNECT,
* you must stop using the SSL context for reading or writing,
* and either free it or call \c mbedtls_ssl_session_reset()
* on it before re-using it for a new connection; the current
* connection must be closed.
*
* \note When this function returns #MBEDTLS_ERR_SSL_CLIENT_RECONNECT
* (which can only happen server-side), it means that a client
* is initiating a new connection using the same source port.
* You can either treat that as a connection close and wait
* for the client to resend a ClientHello, or directly
* continue with \c mbedtls_ssl_handshake() with the same
* context (as it has been reset internally). Either way, you
* must make sure this is seen by the application as a new
* connection: application state, if any, should be reset, and
* most importantly the identity of the client must be checked
* again. WARNING: not validating the identity of the client
* again, or not transmitting the new identity to the
* application layer, would allow authentication bypass!
*
* \note Remarks regarding event-driven DTLS:
* - If the function returns #MBEDTLS_ERR_SSL_WANT_READ, no datagram
* from the underlying transport layer is currently being processed,
* and it is safe to idle until the timer or the underlying transport
* signal a new event.
* - This function may return MBEDTLS_ERR_SSL_WANT_READ even if data was
* initially available on the underlying transport, as this data may have
* been only e.g. duplicated messages or a renegotiation request.
* Therefore, you must be prepared to receive MBEDTLS_ERR_SSL_WANT_READ even
* when reacting to an incoming-data event from the underlying transport.
* - On success, the datagram of the underlying transport that is currently
* being processed may contain further DTLS records. You should call
* \c mbedtls_ssl_check_pending to check for remaining records.
*
*/
int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len );
/**
* \brief Try to write exactly 'len' application data bytes
*
* \warning This function will do partial writes in some cases. If the
* return value is non-negative but less than length, the
* function must be called again with updated arguments:
* buf + ret, len - ret (if ret is the return value) until
* it returns a value equal to the last 'len' argument.
*
* \param ssl SSL context
* \param buf buffer holding the data
* \param len how many bytes must be written
*
* \return The (non-negative) number of bytes actually written if
* successful (may be less than \p len).
* \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
* if the handshake is incomplete and waiting for data to
* be available for reading from or writing to the underlying
* transport - in this case you must call this function again
* when the underlying transport is ready for the operation.
* \return #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS if an asynchronous
* operation is in progress (see
* mbedtls_ssl_conf_async_private_cb()) - in this case you
* must call this function again when the operation is ready.
* \return #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS if a cryptographic
* operation is in progress (see mbedtls_ecp_set_max_ops()) -
* in this case you must call this function again to complete
* the handshake when you're done attending other tasks.
* \return Another SSL error code - in this case you must stop using
* the context (see below).
*
* \warning If this function returns something other than
* a non-negative value,
* #MBEDTLS_ERR_SSL_WANT_READ,
* #MBEDTLS_ERR_SSL_WANT_WRITE,
* #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
* #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
* you must stop using the SSL context for reading or writing,
* and either free it or call \c mbedtls_ssl_session_reset()
* on it before re-using it for a new connection; the current
* connection must be closed.
*
* \note When this function returns #MBEDTLS_ERR_SSL_WANT_WRITE/READ,
* it must be called later with the *same* arguments,
* until it returns a value greater that or equal to 0. When
* the function returns #MBEDTLS_ERR_SSL_WANT_WRITE there may be
* some partial data in the output buffer, however this is not
* yet sent.
*
* \note If the requested length is greater than the maximum
* fragment length (either the built-in limit or the one set
* or negotiated with the peer), then:
* - with TLS, less bytes than requested are written.
* - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned.
* \c mbedtls_ssl_get_max_frag_len() may be used to query the
* active maximum fragment length.
*
* \note Attempting to write 0 bytes will result in an empty TLS
* application record being sent.
*/
int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len );
/**
* \brief Send an alert message
*
* \param ssl SSL context
* \param level The alert level of the message
* (MBEDTLS_SSL_ALERT_LEVEL_WARNING or MBEDTLS_SSL_ALERT_LEVEL_FATAL)
* \param message The alert message (SSL_ALERT_MSG_*)
*
* \return 0 if successful, or a specific SSL error code.
*
* \note If this function returns something other than 0 or
* MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
* the SSL context for reading or writing, and either free it or
* call \c mbedtls_ssl_session_reset() on it before re-using it
* for a new connection; the current connection must be closed.
*/
int mbedtls_ssl_send_alert_message( mbedtls_ssl_context *ssl,
unsigned char level,
unsigned char message );
/**
* \brief Notify the peer that the connection is being closed
*
* \param ssl SSL context
*
* \return 0 if successful, or a specific SSL error code.
*
* \note If this function returns something other than 0 or
* MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop using
* the SSL context for reading or writing, and either free it or
* call \c mbedtls_ssl_session_reset() on it before re-using it
* for a new connection; the current connection must be closed.
*/
int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl );
/**
* \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 relevant 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
*
* \note A session object can be freed even if the SSL context
* that was used to retrieve the session is still in use.
*
* \param session SSL session
*/
void mbedtls_ssl_session_free( mbedtls_ssl_session *session );
#ifdef __cplusplus
}
#endif
#endif /* ssl.h */