Hello.
I previously made a post in which I reported that I was unable to make a UDP socket work on Ubuntu. The problem was solved and I got a lot of help from the community, thanks to Richard and Alfred.
If you can help me again, I would be grateful. Let me explain what I want to do:
I want to open an entrance / exit gate of my laboratory using UDP, for that, I run a Java program on a Raspberry Pi that receives a message and it opens or closes.
I have a simulator for this gate and I make it available to students so that they can all use it on their own computers, for obvious reasons, it is undesirable that they all use the same real gate at the same time for testing.
I tried to use the new 10.4.0 Posix / GCC library together with the simulator on the same host to implement it, however, I was unable to make it work. Here, Alfred explains that it is not possible to make them work in the same Ubuntu Box.
I tried a Fedora virtual machine to host the simulator. To check if the connection between my machine and the virtual machine worked, I sent pings and sent UDP packets via command lines, which worked.
When I ran and modified the main_networking.c program for the example shown in:
No packages arrived at the Fedora host.
The program is below:
/*
* FreeRTOS Kernel V10.4.0
* Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* http://www.FreeRTOS.org
* http://aws.amazon.com/freertos
*
* 1 tab == 4 spaces!
*/
/*
* This project is a cut down version of the project described on the following
* link. Only the simple UDP client and server and the TCP echo clients are
* included in the build:
* http://www.freertos.org/FreeRTOS-Plus/FreeRTOS_Plus_TCP/examples_FreeRTOS_simulator.html
*/
/* Standard includes. */
#include <stdio.h>
#include <time.h>
#include <unistd.h>
/* FreeRTOS includes. */
#include <FreeRTOS.h>
#include "task.h"
/* Demo application includes. */
#include "FreeRTOS_IP.h"
#include "FreeRTOS_Sockets.h"
/*#include "SimpleUDPClientAndServer.h" */
/*#include "SimpleTCPEchoServer.h" */
/*#include "TCPEchoClient_SingleTasks.h" */
/*#include "demo_logging.h" */
#include "TCPEchoClient_SingleTasks.h"
/* Simple UDP client and server task parameters. */
#define mainSIMPLE_UDP_CLIENT_SERVER_TASK_PRIORITY ( tskIDLE_PRIORITY )
#define mainSIMPLE_UDP_CLIENT_SERVER_PORT ( 5005UL )
/* Echo client task parameters - used for both TCP and UDP echo clients. */
#define mainECHO_CLIENT_TASK_STACK_SIZE ( configMINIMAL_STACK_SIZE * 2 ) /* Not used in the linux port. */
#define mainECHO_CLIENT_TASK_PRIORITY ( tskIDLE_PRIORITY + 1 )
/* Echo server task parameters. */
#define mainECHO_SERVER_TASK_STACK_SIZE ( configMINIMAL_STACK_SIZE * 2 ) /* Not used in the linux port. */
#define mainECHO_SERVER_TASK_PRIORITY ( tskIDLE_PRIORITY + 1 )
/* Define a name that will be used for LLMNR and NBNS searches. */
#define mainHOST_NAME "RTOSDemo"
#define mainDEVICE_NICK_NAME "linux_demo"
/* Set the following constants to 1 or 0 to define which tasks to include and
exclude:
mainCREATE_TCP_ECHO_TASKS_SINGLE: When set to 1 a set of tasks are created that
send TCP echo requests to the standard echo port (port 7), then wait for and
verify the echo reply, from within the same task (Tx and Rx are performed in the
same RTOS task). The IP address of the echo server must be configured using the
configECHO_SERVER_ADDR0 to configECHO_SERVER_ADDR3 constants in
FreeRTOSConfig.h.
*/
#define mainCREATE_TCP_ECHO_TASKS_SINGLE 0
/*-----------------------------------------------------------*/
/*
* Just seeds the simple pseudo random number generator.
*/
static void prvSRand( UBaseType_t ulSeed );
/*
* Miscellaneous initialisation including preparing the logging and seeding the
* random number generator.
*/
static void prvMiscInitialisation( void );
/* The default IP and MAC address used by the demo. The address configuration
defined here will be used if ipconfigUSE_DHCP is 0, or if ipconfigUSE_DHCP is
1 but a DHCP server could not be contacted. See the online documentation for
more information. */
static const uint8_t ucIPAddress[ 4 ] = { configIP_ADDR0, configIP_ADDR1, configIP_ADDR2, configIP_ADDR3 };
static const uint8_t ucNetMask[ 4 ] = { configNET_MASK0, configNET_MASK1, configNET_MASK2, configNET_MASK3 };
static const uint8_t ucGatewayAddress[ 4 ] = { configGATEWAY_ADDR0, configGATEWAY_ADDR1, configGATEWAY_ADDR2, configGATEWAY_ADDR3 };
static const uint8_t ucDNSServerAddress[ 4 ] = { configDNS_SERVER_ADDR0, configDNS_SERVER_ADDR1, configDNS_SERVER_ADDR2, configDNS_SERVER_ADDR3 };
/* Set the following constant to pdTRUE to log using the method indicated by the
name of the constant, or pdFALSE to not log using the method indicated by the
name of the constant. Options include to standard out (xLogToStdout), to a disk
file (xLogToFile), and to a UDP port (xLogToUDP). If xLogToUDP is set to pdTRUE
then UDP messages are sent to the IP address configured as the echo server
address (see the configECHO_SERVER_ADDR0 definitions in FreeRTOSConfig.h) and
the port number set by configPRINT_PORT in FreeRTOSConfig.h. */
const BaseType_t xLogToStdout = pdTRUE, xLogToFile = pdFALSE, xLogToUDP = pdFALSE;
/* Default MAC address configuration. The demo creates a virtual network
connection that uses this MAC address by accessing the raw Ethernet data
to and from a real network connection on the host PC. See the
configNETWORK_INTERFACE_TO_USE definition for information on how to configure
the real network connection to use. */
const uint8_t ucMACAddress[ 6 ] = { configMAC_ADDR0, configMAC_ADDR1, configMAC_ADDR2, configMAC_ADDR3, configMAC_ADDR4, configMAC_ADDR5 };
/* Use by the pseudo random number generator. */
static UBaseType_t ulNextRand;
/*-----------------------------------------------------------*/
void main_tcp_echo_client_tasks( void )
{
const uint32_t ulLongTime_ms = pdMS_TO_TICKS( 1000UL );
/*
* Instructions for using this project are provided on:
* http://www.freertos.org/FreeRTOS-Plus/FreeRTOS_Plus_TCP/examples_FreeRTOS_simulator.html
*/
/* Miscellaneous initialisation including preparing the logging and seeding
the random number generator. */
prvMiscInitialisation();
/* Initialise the network interface.
***NOTE*** Tasks that use the network are created in the network event hook
when the network is connected and ready for use (see the definition of
vApplicationIPNetworkEventHook() below). The address values passed in here
are used if ipconfigUSE_DHCP is set to 0, or if ipconfigUSE_DHCP is set to 1
but a DHCP server cannot be contacted. */
FreeRTOS_debug_printf( ( "FreeRTOS_IPInit\n" ) );
FreeRTOS_IPInit( ucIPAddress,
ucNetMask,
ucGatewayAddress,
ucDNSServerAddress,
ucMACAddress );
/* Start the RTOS scheduler. */
FreeRTOS_debug_printf( ( "vTaskStartScheduler\n" ) );
vTaskStartScheduler();
FreeRTOS_debug_printf( ( "Should not reach this point after scheduler\n" ) );
/* If all is well, the scheduler will now be running, and the following
line will never be reached. If the following line does execute, then
there was insufficient FreeRTOS heap memory available for the idle and/or
timer tasks to be created. See the memory management section on the
FreeRTOS web site for more details (this is standard text that is not not
really applicable to the Linux simulator port). */
for( ; ; )
{
usleep( ulLongTime_ms * 1000 );
}
}
/*-----------------------------------------------------------*/
static void vUDPSendUsingStandardInterface( void *pvParameters )
{
Socket_t xSocket;
struct freertos_sockaddr xDestinationAddress;
uint8_t cString[ 50 ];
uint32_t ulCount = 0UL;
const TickType_t x1000ms = 1000UL / portTICK_PERIOD_MS;
/* Send strings to port 10000 on IP address 192.168.0.50. */
xDestinationAddress.sin_addr = FreeRTOS_inet_addr( "192.168.2.107" );
xDestinationAddress.sin_port = FreeRTOS_htons( 5000 );
/* Create the socket. */
xSocket = FreeRTOS_socket( FREERTOS_AF_INET,
FREERTOS_SOCK_DGRAM,/*FREERTOS_SOCK_DGRAM for UDP.*/
FREERTOS_IPPROTO_UDP );
/* Check the socket was created. */
configASSERT( xSocket != FREERTOS_INVALID_SOCKET );
/* NOTE: FreeRTOS_bind() is not called. This will only work if
ipconfigALLOW_SOCKET_SEND_WITHOUT_BIND is set to 1 in FreeRTOSIPConfig.h. */
for( ;; )
{
/* Create the string that is sent. */
sprintf( cString,
"Standard send message number %lurn",
ulCount );
FreeRTOS_sendto( xSocket,
cString,
strlen( cString ),
0,
&xDestinationAddress,
sizeof( xDestinationAddress ) );
ulCount++;
/* Wait until it is time to send again. */
vTaskDelay( 1000 );
}
}
/* Called by FreeRTOS+TCP when the network connects or disconnects. Disconnect
events are only received if implemented in the MAC driver. */
void vApplicationIPNetworkEventHook( eIPCallbackEvent_t eNetworkEvent )
{
uint32_t ulIPAddress, ulNetMask, ulGatewayAddress, ulDNSServerAddress;
char cBuffer[ 16 ];
static BaseType_t xTasksAlreadyCreated = pdFALSE;
/* If the network has just come up...*/
if( eNetworkEvent == eNetworkUp )
{
/* Create the tasks that use the IP stack if they have not already been
created. */
if( xTasksAlreadyCreated == pdFALSE )
{
xTaskCreate( vUDPSendUsingStandardInterface, /* The function that implements the task. */
"Echo0", /* Just a text name for the task to aid debugging. */
configMINIMAL_STACK_SIZE, /* The stack size is defined in FreeRTOSIPConfig.h. */
NULL, /* The task parameter, not used in this case. */
5, /* The priority assigned to the task is defined in FreeRTOSConfig.h. */
NULL ); /* The task handle is not used. */
xTasksAlreadyCreated = pdTRUE;
}
/* Print out the network configuration, which may have come from a DHCP
server. */
FreeRTOS_GetAddressConfiguration( &ulIPAddress, &ulNetMask, &ulGatewayAddress, &ulDNSServerAddress );
FreeRTOS_inet_ntoa( ulIPAddress, cBuffer );
FreeRTOS_printf( ( "\r\n\r\nIP Address: %s\r\n", cBuffer ) );
FreeRTOS_inet_ntoa( ulNetMask, cBuffer );
FreeRTOS_printf( ( "Subnet Mask: %s\r\n", cBuffer ) );
FreeRTOS_inet_ntoa( ulGatewayAddress, cBuffer );
FreeRTOS_printf( ( "Gateway Address: %s\r\n", cBuffer ) );
FreeRTOS_inet_ntoa( ulDNSServerAddress, cBuffer );
FreeRTOS_printf( ( "DNS Server Address: %s\r\n\r\n\r\n", cBuffer ) );
}
else
{
FreeRTOS_printf( "Application idle hook network down\n" );
}
}
/*-----------------------------------------------------------*/
UBaseType_t uxRand( void )
{
const uint32_t ulMultiplier = 0x015a4e35UL, ulIncrement = 1UL;
/* Utility function to generate a pseudo random number. */
ulNextRand = ( ulMultiplier * ulNextRand ) + ulIncrement;
return( ( int ) ( ulNextRand >> 16UL ) & 0x7fffUL );
}
/*-----------------------------------------------------------*/
static void prvSRand( UBaseType_t ulSeed )
{
/* Utility function to seed the pseudo random number generator. */
ulNextRand = ulSeed;
}
/*-----------------------------------------------------------*/
static void prvMiscInitialisation( void )
{
time_t xTimeNow;
/* Seed the random number generator. */
time( &xTimeNow );
FreeRTOS_debug_printf( ( "Seed for randomiser: %lu\n", xTimeNow ) );
prvSRand( ( uint32_t ) xTimeNow );
FreeRTOS_debug_printf( ( "Random numbers: %08X %08X %08X %08X\n",
ipconfigRAND32(),
ipconfigRAND32(),
ipconfigRAND32(),
ipconfigRAND32() ) );
}
/*-----------------------------------------------------------*/
#if ( ipconfigUSE_LLMNR != 0 ) || ( ipconfigUSE_NBNS != 0 ) || ( ipconfigDHCP_REGISTER_HOSTNAME == 1 )
const char * pcApplicationHostnameHook( void )
{
/* Assign the name "FreeRTOS" to this network node. This function will
be called during the DHCP: the machine will be registered with an IP
address plus this name. */
return mainHOST_NAME;
}
#endif
/*-----------------------------------------------------------*/
#if ( ipconfigUSE_LLMNR != 0 ) || ( ipconfigUSE_NBNS != 0 )
BaseType_t xApplicationDNSQueryHook( const char *pcName )
{
BaseType_t xReturn;
/* Determine if a name lookup is for this node. Two names are given
to this node: that returned by pcApplicationHostnameHook() and that set
by mainDEVICE_NICK_NAME. */
if( strcasecmp( pcName, pcApplicationHostnameHook() ) == 0 )
{
xReturn = pdPASS;
}
else if( strcasecmp( pcName, mainDEVICE_NICK_NAME ) == 0 )
{
xReturn = pdPASS;
}
else
{
xReturn = pdFAIL;
}
return xReturn;
}
#endif /* if ( ipconfigUSE_LLMNR != 0 ) || ( ipconfigUSE_NBNS != 0 ) */
/*
* Callback that provides the inputs necessary to generate a randomized TCP
* Initial Sequence Number per RFC 6528. THIS IS ONLY A DUMMY IMPLEMENTATION
* THAT RETURNS A PSEUDO RANDOM NUMBER SO IS NOT INTENDED FOR USE IN PRODUCTION
* SYSTEMS.
*/
extern uint32_t ulApplicationGetNextSequenceNumber( uint32_t ulSourceAddress,
uint16_t usSourcePort,
uint32_t ulDestinationAddress,
uint16_t usDestinationPort )
{
( void ) ulSourceAddress;
( void ) usSourcePort;
( void ) ulDestinationAddress;
( void ) usDestinationPort;
return uxRand();
}
/*
* Supply a random number to FreeRTOS+TCP stack.
* THIS IS ONLY A DUMMY IMPLEMENTATION THAT RETURNS A PSEUDO RANDOM NUMBER
* SO IS NOT INTENDED FOR USE IN PRODUCTION SYSTEMS.
*/
BaseType_t xApplicationGetRandomNumber( uint32_t * pulNumber )
{
*( pulNumber ) = uxRand();
return pdTRUE;
}
The only changes to the header files were:
Address of my VBox
#define configECHO_SERVER_ADDR0 192
#define configECHO_SERVER_ADDR1 168
#define configECHO_SERVER_ADDR2 2
#define configECHO_SERVER_ADDR3 107
Local IP
#define configIP_ADDR0 127
#define configIP_ADDR1 0
#define configIP_ADDR2 0
#define configIP_ADDR3 1
Gateway
#define configGATEWAY_ADDR0 192
#define configGATEWAY_ADDR1 168
#define configGATEWAY_ADDR2 2
#define configGATEWAY_ADDR3 1
Net Mask
#define configNET_MASK0 0
#define configNET_MASK1 0
#define configNET_MASK2 0
#define configNET_MASK3 255
and some other hooks disabled
#define configUSE_IDLE_HOOK 0
#define configUSE_TICK_HOOK 0
#define configUSE_DAEMON_TASK_STARTUP_HOOK 0
Could you help me again with this problem?
Thank you.