net.h

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