tls_socket.c

00001 /*
00002 MiniTLS - A super trimmed down TLS/SSL Library for embedded devices
00003 Author: Donatien Garnier
00004 Copyright (C) 2013-2014 AppNearMe Ltd
00005 
00006 This program is free software; you can redistribute it and/or
00007 modify it under the terms of the GNU General Public License
00008 as published by the Free Software Foundation; either version 2
00009 of the License, or (at your option) any later version.
00010 
00011 This program is distributed in the hope that it will be useful,
00012 but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 GNU General Public License for more details.
00015 
00016 You should have received a copy of the GNU General Public License
00017 along with this program; if not, write to the Free Software
00018 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
00019 *//**
00020  * \file tls_socket.c
00021  * \copyright Copyright (c) AppNearMe Ltd 2013
00022  * \author Donatien Garnier
00023  */
00024 
00025 #define __DEBUG__ 4
00026 #ifndef __MODULE__
00027 #define __MODULE__ "tls_socket.c"
00028 #endif
00029 
00030 
00031 #include "core/fwk.h"
00032 #include "inc/minitls_errors.h"
00033 
00034 #include "tls_socket.h"
00035 
00036 minitls_err_t tls_socket_init(tls_socket_t* socket, minitls_t* minitls,
00037     uint8_t* write_buffer, size_t write_buffer_size, uint8_t* read_buffer, size_t read_buffer_size)
00038 {
00039   socket->minitls = minitls;
00040 
00041   socket->events = NULL;
00042 
00043   socket->read_buffer = NULL;
00044   buffer_init(&socket->write_buffer, write_buffer, write_buffer_size);
00045 
00046   socket->session.session_id_length = 0;
00047 
00048   minitls_err_t ret = tls_record_init(&socket->record, socket, read_buffer, read_buffer_size);
00049   if(ret)
00050   {
00051     return ret;
00052   }
00053 
00054   ret = tls_handshake_init(&socket->handshake, socket);
00055   if(ret)
00056   {
00057     return ret;
00058   }
00059 
00060   return MINITLS_OK;
00061 }
00062 
00063 minitls_err_t tls_socket_connect(tls_socket_t* socket, const char* hostname, uint16_t port, int timeout)
00064 {
00065   minitls_err_t ret = tls_record_connect(&socket->record, hostname, port);
00066   if(ret)
00067   {
00068     ERR("Could not connect");
00069     return ret;
00070   }
00071 
00072   //TODO we could allocate the handshake structure here to save memory
00073 
00074   ret = tls_handshake_start(&socket->handshake);
00075   if(ret)
00076   {
00077     ERR("Could not start handshake");
00078     return ret;
00079   }
00080 
00081   //Now wait for handshake to finish processing (or fail)
00082   while(!tls_handshake_is_done(&socket->handshake))
00083   {
00084     DBG("Handshaking...");
00085     ret = tls_record_process(&socket->record);
00086     if(ret)
00087     {
00088       ERR("Processing error");
00089       return ret;
00090     }
00091   }
00092 
00093   DBG("Connected");
00094 
00095   return MINITLS_OK;
00096 }
00097 
00098 void tls_socket_copy_session(tls_socket_t* to, tls_socket_t* from)
00099 {
00100   memcpy(&to->session, &from->session, sizeof(tls_session_t));
00101 }
00102 
00103 //Events API -- select like
00104 minitls_err_t tls_socket_event_list_init(tls_socket_event_list_t* list)
00105 {
00106   list->head = NULL;
00107 
00108   //Create semaphore
00109 /*  list->sem = rtos_sem_create(1, 0);*/
00110   /*if(list->sem == NULL)
00111   {
00112     return TLS_ERR_MEMORY;
00113   }*/ //FIXME
00114 
00115   return MINITLS_OK;
00116 }
00117 
00118 minitls_err_t tls_socket_event_init_and_register(tls_socket_event_t* event, tls_socket_event_list_t* list, tls_socket_t* socket, bool read, bool write)
00119 {
00120   //Init event
00121   event->socket = socket;
00122   event->read = read;
00123   event->write = write;
00124   event->list = list;
00125   event->socket_list_next = NULL;
00126   event->event_list_next = NULL;
00127 
00128   //Add to select list (tail)
00129   if(list->head != NULL)
00130   {
00131     tls_socket_event_t* previous_event = list->head;
00132     while( previous_event->event_list_next != NULL )
00133     {
00134       previous_event = previous_event->event_list_next;
00135     }
00136     previous_event->event_list_next = event;
00137   }
00138   else
00139   {
00140     list->head = event;
00141   }
00142 
00143   //Add to socket's event list (tail)
00144   if(socket->events != NULL)
00145   {
00146     tls_socket_event_t* previous_event = socket->events;
00147     while( previous_event->socket_list_next != NULL )
00148     {
00149       previous_event = previous_event->socket_list_next;
00150     }
00151     previous_event->socket_list_next = event;
00152   }
00153   else
00154   {
00155     socket->events = event;
00156   }
00157 
00158   return MINITLS_OK;
00159 }
00160 
00161 minitls_err_t tls_socket_event_list_wait(tls_socket_event_list_t* list, int timeout) //All events unregistered at the end of wait, timeout in ms, -1 for infinite timeout
00162 {/*
00163   if( rtos_sem_get(list->sem, timeout) ) //FIXME
00164   {*/
00165     return MINITLS_OK;
00166   /*}
00167   else
00168   {
00169     return TLS_ERR_TIMEOUT;
00170   }*/
00171 }
00172 
00173 //These calls are non-blocking
00174 minitls_err_t tls_socket_read(tls_socket_t* socket, uint8_t* bytes, size_t max_size, size_t* read_size)
00175 {
00176   DBG("Reading at most %d bytes", max_size);
00177   if(socket->read_buffer == NULL) //Socket is not ready
00178   {
00179     WARN("Socket is not ready or has been closed");
00180     *read_size = 0;
00181     return MINITLS_OK;
00182   }
00183 
00184   size_t length = buffer_length(socket->read_buffer);
00185   *read_size = MIN(max_size, length);
00186 
00187   buffer_nbytes_read(socket->read_buffer, bytes, *read_size);
00188 
00189   DBG("%d bytes read", *read_size);
00190 
00191   //If buffer has been fully read, invalidate read_buffer
00192   if( buffer_length(socket->read_buffer) == 0 )
00193   {
00194     socket->read_buffer = NULL;
00195   }
00196 
00197   return MINITLS_OK;
00198 }
00199 
00200 minitls_err_t tls_socket_write(tls_socket_t* socket, uint8_t* bytes, size_t size, size_t* written_size)
00201 {
00202   size_t length = buffer_space(&socket->write_buffer);
00203   *written_size = MIN(size, length);
00204 
00205   buffer_nbytes_write(&socket->write_buffer, bytes, *written_size);
00206 
00207   return MINITLS_OK;
00208 }
00209 
00210 minitls_err_t tls_socket_flush_read(tls_socket_t* socket, int timeout)
00211 {
00212   DBG("Get new bytes");
00213   if( socket->read_buffer != NULL ) //No need to read more bytes
00214   {
00215     WARN("Buffer is already non-empty");
00216     return MINITLS_OK;
00217   }
00218 
00219   tls_record_set_read_timeout(&socket->record, timeout);
00220 
00221   int ret;
00222   do
00223   {
00224     DBG("Processing TLS packet");
00225     ret = tls_record_process(&socket->record);
00226     if(ret)
00227     {
00228       return ret;
00229     }
00230   } while( socket->read_buffer == NULL );
00231 
00232   DBG("Buffer has been filled");
00233   return MINITLS_OK;
00234 }
00235 
00236 minitls_err_t tls_socket_flush_write(tls_socket_t* socket, int timeout)
00237 {
00238   if(buffer_length(&socket->write_buffer) == 0)
00239   {
00240     return MINITLS_OK; //Useless to flush
00241   }
00242 
00243   tls_record_set_write_timeout(&socket->record, timeout);
00244 
00245   //Pass buffer to record layer
00246   minitls_err_t ret = tls_record_send(&socket->record, TLS_APPLICATION_DATA, &socket->write_buffer);
00247 
00248   //TODO: Advertise writeable here
00249 
00250   if(ret)
00251   {
00252     return ret;
00253   }
00254 
00255   return MINITLS_OK;
00256 }
00257 
00258 //Called from record layer
00259 minitls_err_t tls_socket_readable_callback(tls_socket_t* socket, buffer_t* buffer)
00260 {
00261   socket->read_buffer = buffer;
00262 
00263   //Process events
00264 
00265   return MINITLS_OK;
00266 }
00267 
00268 minitls_err_t tls_socket_close(tls_socket_t* socket)
00269 {
00270   minitls_err_t ret = tls_record_close(&socket->record);
00271   if(ret)
00272   {
00273     return ret;
00274   }
00275   return MINITLS_OK;
00276 }