net_sockets.h

00001 /**
00002  * \file net_sockets.h
00003  *
00004  * \brief Network communication functions
00005  */
00006 /*
00007  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
00008  *  SPDX-License-Identifier: Apache-2.0
00009  *
00010  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00011  *  not use this file except in compliance with the License.
00012  *  You may obtain a copy of the License at
00013  *
00014  *  http://www.apache.org/licenses/LICENSE-2.0
00015  *
00016  *  Unless required by applicable law or agreed to in writing, software
00017  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00018  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00019  *  See the License for the specific language governing permissions and
00020  *  limitations under the License.
00021  *
00022  *  This file is part of mbed TLS (https://tls.mbed.org)
00023  */
00024 #ifndef MBEDTLS_NET_SOCKETS_H
00025 #define MBEDTLS_NET_SOCKETS_H
00026 
00027 #if !defined(MBEDTLS_CONFIG_FILE)
00028 #include "config.h"
00029 #else
00030 #include MBEDTLS_CONFIG_FILE
00031 #endif
00032 
00033 #include "ssl.h"
00034 
00035 #include <stddef.h>
00036 #include <stdint.h>
00037 
00038 #define MBEDTLS_ERR_NET_SOCKET_FAILED                     -0x0042  /**< Failed to open a socket. */
00039 #define MBEDTLS_ERR_NET_CONNECT_FAILED                    -0x0044  /**< The connection to the given server / port failed. */
00040 #define MBEDTLS_ERR_NET_BIND_FAILED                       -0x0046  /**< Binding of the socket failed. */
00041 #define MBEDTLS_ERR_NET_LISTEN_FAILED                     -0x0048  /**< Could not listen on the socket. */
00042 #define MBEDTLS_ERR_NET_ACCEPT_FAILED                     -0x004A  /**< Could not accept the incoming connection. */
00043 #define MBEDTLS_ERR_NET_RECV_FAILED                       -0x004C  /**< Reading information from the socket failed. */
00044 #define MBEDTLS_ERR_NET_SEND_FAILED                       -0x004E  /**< Sending information through the socket failed. */
00045 #define MBEDTLS_ERR_NET_CONN_RESET                        -0x0050  /**< Connection was reset by peer. */
00046 #define MBEDTLS_ERR_NET_UNKNOWN_HOST                      -0x0052  /**< Failed to get an IP address for the given hostname. */
00047 #define MBEDTLS_ERR_NET_BUFFER_TOO_SMALL                  -0x0043  /**< Buffer is too small to hold the data. */
00048 #define MBEDTLS_ERR_NET_INVALID_CONTEXT                   -0x0045  /**< The context is invalid, eg because it was free()ed. */
00049 
00050 #define MBEDTLS_NET_LISTEN_BACKLOG         10 /**< The backlog that listen() should use. */
00051 
00052 #define MBEDTLS_NET_PROTO_TCP 0 /**< The TCP transport protocol */
00053 #define MBEDTLS_NET_PROTO_UDP 1 /**< The UDP transport protocol */
00054 
00055 #ifdef __cplusplus
00056 extern "C" {
00057 #endif
00058 
00059 /**
00060  * Wrapper type for sockets.
00061  *
00062  * Currently backed by just a file descriptor, but might be more in the future
00063  * (eg two file descriptors for combined IPv4 + IPv6 support, or additional
00064  * structures for hand-made UDP demultiplexing).
00065  */
00066 typedef struct
00067 {
00068     int fd;             /**< The underlying file descriptor                 */
00069 }
00070 mbedtls_net_context;
00071 
00072 /**
00073  * \brief          Initialize a context
00074  *                 Just makes the context ready to be used or freed safely.
00075  *
00076  * \param ctx      Context to initialize
00077  */
00078 void mbedtls_net_init( mbedtls_net_context *ctx );
00079 
00080 /**
00081  * \brief          Initiate a connection with host:port in the given protocol
00082  *
00083  * \param ctx      Socket to use
00084  * \param host     Host to connect to
00085  * \param port     Port to connect to
00086  * \param proto    Protocol: MBEDTLS_NET_PROTO_TCP or MBEDTLS_NET_PROTO_UDP
00087  *
00088  * \return         0 if successful, or one of:
00089  *                      MBEDTLS_ERR_NET_SOCKET_FAILED,
00090  *                      MBEDTLS_ERR_NET_UNKNOWN_HOST,
00091  *                      MBEDTLS_ERR_NET_CONNECT_FAILED
00092  *
00093  * \note           Sets the socket in connected mode even with UDP.
00094  */
00095 int mbedtls_net_connect( mbedtls_net_context *ctx, const char *host, const char *port, int proto );
00096 
00097 /**
00098  * \brief          Create a receiving socket on bind_ip:port in the chosen
00099  *                 protocol. If bind_ip == NULL, all interfaces are bound.
00100  *
00101  * \param ctx      Socket to use
00102  * \param bind_ip  IP to bind to, can be NULL
00103  * \param port     Port number to use
00104  * \param proto    Protocol: MBEDTLS_NET_PROTO_TCP or MBEDTLS_NET_PROTO_UDP
00105  *
00106  * \return         0 if successful, or one of:
00107  *                      MBEDTLS_ERR_NET_SOCKET_FAILED,
00108  *                      MBEDTLS_ERR_NET_BIND_FAILED,
00109  *                      MBEDTLS_ERR_NET_LISTEN_FAILED
00110  *
00111  * \note           Regardless of the protocol, opens the sockets and binds it.
00112  *                 In addition, make the socket listening if protocol is TCP.
00113  */
00114 int mbedtls_net_bind( mbedtls_net_context *ctx, const char *bind_ip, const char *port, int proto );
00115 
00116 /**
00117  * \brief           Accept a connection from a remote client
00118  *
00119  * \param bind_ctx  Relevant socket
00120  * \param client_ctx Will contain the connected client socket
00121  * \param client_ip Will contain the client IP address
00122  * \param buf_size  Size of the client_ip buffer
00123  * \param ip_len    Will receive the size of the client IP written
00124  *
00125  * \return          0 if successful, or
00126  *                  MBEDTLS_ERR_NET_ACCEPT_FAILED, or
00127  *                  MBEDTLS_ERR_NET_BUFFER_TOO_SMALL if buf_size is too small,
00128  *                  MBEDTLS_ERR_SSL_WANT_READ if bind_fd was set to
00129  *                  non-blocking and accept() would block.
00130  */
00131 int mbedtls_net_accept( mbedtls_net_context *bind_ctx,
00132                         mbedtls_net_context *client_ctx,
00133                         void *client_ip, size_t buf_size, size_t *ip_len );
00134 
00135 /**
00136  * \brief          Set the socket blocking
00137  *
00138  * \param ctx      Socket to set
00139  *
00140  * \return         0 if successful, or a non-zero error code
00141  */
00142 int mbedtls_net_set_block( mbedtls_net_context *ctx );
00143 
00144 /**
00145  * \brief          Set the socket non-blocking
00146  *
00147  * \param ctx      Socket to set
00148  *
00149  * \return         0 if successful, or a non-zero error code
00150  */
00151 int mbedtls_net_set_nonblock( mbedtls_net_context *ctx );
00152 
00153 /**
00154  * \brief          Portable usleep helper
00155  *
00156  * \param usec     Amount of microseconds to sleep
00157  *
00158  * \note           Real amount of time slept will not be less than
00159  *                 select()'s timeout granularity (typically, 10ms).
00160  */
00161 void mbedtls_net_usleep( unsigned long usec );
00162 
00163 /**
00164  * \brief          Read at most 'len' characters. If no error occurs,
00165  *                 the actual amount read is returned.
00166  *
00167  * \param ctx      Socket
00168  * \param buf      The buffer to write to
00169  * \param len      Maximum length of the buffer
00170  *
00171  * \return         the number of bytes received,
00172  *                 or a non-zero error code; with a non-blocking socket,
00173  *                 MBEDTLS_ERR_SSL_WANT_READ indicates read() would block.
00174  */
00175 int mbedtls_net_recv( void *ctx, unsigned char *buf, size_t len );
00176 
00177 /**
00178  * \brief          Write at most 'len' characters. If no error occurs,
00179  *                 the actual amount read is returned.
00180  *
00181  * \param ctx      Socket
00182  * \param buf      The buffer to read from
00183  * \param len      The length of the buffer
00184  *
00185  * \return         the number of bytes sent,
00186  *                 or a non-zero error code; with a non-blocking socket,
00187  *                 MBEDTLS_ERR_SSL_WANT_WRITE indicates write() would block.
00188  */
00189 int mbedtls_net_send( void *ctx, const unsigned char *buf, size_t len );
00190 
00191 /**
00192  * \brief          Read at most 'len' characters, blocking for at most
00193  *                 'timeout' seconds. If no error occurs, the actual amount
00194  *                 read is returned.
00195  *
00196  * \param ctx      Socket
00197  * \param buf      The buffer to write to
00198  * \param len      Maximum length of the buffer
00199  * \param timeout  Maximum number of milliseconds to wait for data
00200  *                 0 means no timeout (wait forever)
00201  *
00202  * \return         the number of bytes received,
00203  *                 or a non-zero error code:
00204  *                 MBEDTLS_ERR_SSL_TIMEOUT if the operation timed out,
00205  *                 MBEDTLS_ERR_SSL_WANT_READ if interrupted by a signal.
00206  *
00207  * \note           This function will block (until data becomes available or
00208  *                 timeout is reached) even if the socket is set to
00209  *                 non-blocking. Handling timeouts with non-blocking reads
00210  *                 requires a different strategy.
00211  */
00212 int mbedtls_net_recv_timeout( void *ctx, unsigned char *buf, size_t len,
00213                       uint32_t timeout );
00214 
00215 /**
00216  * \brief          Gracefully shutdown the connection and free associated data
00217  *
00218  * \param ctx      The context to free
00219  */
00220 void mbedtls_net_free( mbedtls_net_context *ctx );
00221 
00222 #ifdef __cplusplus
00223 }
00224 #endif
00225 
00226 #endif /* net_sockets.h */