I'm currently trying to send a SMS with Camel SMPP but I'm failing on sending it to a specific destination port.
Actually nothing port related happens on my SMPP server.
Here is my current code in my Processor :
exchange.getOut().setHeader("CamelSmppAlphabet", Alphabet.ALPHA_8_BIT.value());
exchange.getOut().setHeader("CamelSmppDataCoding", 4);
short destport = 5000;
short srcport = 0;
Map<java.lang.Short, java.lang.Short> optParameters = new HashMap<java.lang.Short, java.lang.Short>();
optParameters.put(OptionalParameter.Tag.DESTINATION_PORT.code(), destport);
optParameters.put(OptionalParameter.Tag.SOURCE_PORT.code(), srcport);
exchange.getOut().setHeader("CamelSmppOptionalParameter", optParameters);
Am I doing something wrong ? If so how am I supposed to send my message to a specific destination Port ?
Thanks for your help
Related
I want to connect two F746ZG boards so that they can communicate via TCP. I am using the STM implementation of LwIP with the netconn API. The IP address is supplied via DHCP, but it is always the same address. Also, the address matches the expected value. The problem I am facing is that the client seemingly can't establish a connection. I am binding the connection to port 8880. Since I ran into this issue, I have written a debug client that should just periodically send a predefined message to a server. Here is the code for the client:
static void tcpecho_client_thread(void const *arg)
{
struct netconn *xNetConn = NULL;
err_t bind_err, connect_err;
char* b_data = "OK"; // Data to be sent
uint16_t b_len = sizeof ( b_data );
IP4_ADDR(&local_ip, IP_ADDR0_CLIENT, IP_ADDR1_CLIENT, IP_ADDR2_CLIENT, IP_ADDR3_CLIENT);
IP4_ADDR(&pc_ip, IP_ADDR0_PC, IP_ADDR0_PC, IP_ADDR2_PC, IP_ADDR3_PC);
xNetConn = netconn_new ( NETCONN_TCP );
if (xNetConn != NULL){
bind_err = netconn_bind ( xNetConn, &local_ip, TCP_PORT_NETCONN );
if(bind_err == ERR_OK){
// Try to connect to server
for(;;){
connect_err = netconn_connect ( xNetConn, &pc_ip, TCP_PORT_NETCONN);
if (connect_err == ERR_OK){
// We are connected
while(1){
BSP_LED_On(LED1);
netconn_write(xNetConn, b_data, b_len, NETCONN_COPY);
vTaskDelay(1000); // To see the result easily in Comm Operator
}
}
}
}else{
// Failed to bind the connection
BSP_LED_On(LED3);
}
}else{
// Failed to allocate a new connection
BSP_LED_On(LED3);
}
}
When I debug this, netconn_connect never manages to actually connect to something. Since I am able to ping the board and get a response, I am confused, what is going wrong here. I have tried to use Hercules to set up a TCP server on my PC so that the board can connect to that, but that also doesn't work. Using Wireshark, I can see the responses to my ping command coming in, but I don't see anything that would indicate the board trying to connect to my PC.
I have tested the corresponding server on the second board, but that runs fine. I can connect to it with Hercules and send data, so I doubt there is anything fundamentally wrong with the LwIP stack.
What I could guess is that I messed up the netconn_bind, I am not 100% sure what IP you are supposed to bind the connection to. The way it currently is, is how I read the documentation. For the server, I have bound it to IP_ADDR_ANY. Besides that, my implementation mostly matches with the examples you can find online (e.g. LwIP Wiki).
I have figured out the problem. After I delete the netconn_bind call, everything works fine for me.
I am using libpcap to capture packet with the following filter:
"tcp[tcpflags] & (tcp-syn) != 0 and not net 127.0.0.1"
But I actually want to get the packet only if the sender is the client (SYN-SENT).
Basically what I am trying to do is to get inform only for new connection and not multiple time for every connection.
Is there a way to do that?
If you only want the SYN from the client but not the SYN+ACK from the server use:
tcp[tcpflags] & (tcp-syn|tcp-ack) == tcp-syn
I'm using the Eclipse Paho MQTT C client to connect to a mosquitto broker with TLS using openssl. This is part of my code:
MQTTClient client;
MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer;
MQTTClient_message pubmsg = MQTTClient_message_initializer;
MQTTClient_SSLOptions sslOptions = MQTTClient_SSLOptions_initializer;
MQTTClient_deliveryToken token;
int rc;
MQTTClient_create(&client, ADDRESS, CLIENTID,
MQTTCLIENT_PERSISTENCE_NONE, NULL);
conn_opts.keepAliveInterval = 20;
conn_opts.cleansession = 1;
/* TLS */
sslOptions.enableServerCertAuth = 0;
sslOptions.trustStore = "ca_rsp.crt";
conn_opts.ssl = &sslOptions;
if ((rc = MQTTClient_connect(client, &conn_opts)) != MQTTCLIENT_SUCCESS)
{
printf("Failed to connect, return code %d\n", rc);
exit(EXIT_FAILURE);
}
Actually every time I reconnect to the broker, the client make a full handshake. I would like to use the TLS session resumption to reduce the overhead. I've search around the web but I haven't found any example of how o implement that in a simple way.
Any suggestion?
Thanks
This came up recently on the mosquitto dev mailing list here https://dev.eclipse.org/mhonarc/lists/mosquitto-dev/msg01606.html
The following excerpt seams to imply it may not be possible just yet with the code as it is.
How can I use Mosquitto / OpenSSL C API to leverage session tickets in an
MQTT C client ?
Not at the moment, this needs code changes that are a bit more
involved - it looks like we need to use SSL_set_session() to apply a
saved session to your client and SSL_CTX_sess_set_new_cb() to save the
session out.
Is there any way I could persist session tickets on the clients, so they
would remain valid across reboot ?
With the above changes, yes.
Make conn_opts.cleansession = 0;
Disabling the cleansession flag in PAHO-client programs enables session resumption.
I have already verified it with wireshark.
With session Resumption, 1st packet transmission
We can see 4 times communication between server and client in 1 image and even certificates are transferred.
With session Resumption ,screenshot taken for 2nd packet transmission
Observe both images carefully , there is only 3 times communication between server and client in2 image, hence the server negotiates not to perform full handshake.
Session resumption time limit is 7200 seconds.
But setting the cleansession flag to 1 will always perform full handshake which means no session resumption.
I feel it was a good decision taken by PAHO people who made clean session flag linked with session resumption because mosquitto client provided in github lacks this inbuilt feature of session resumption.
Go through the specification of MQTT v3.1.1
Or refer MQTT specification in their website
I'm new to C and for a homework exam I must implement a simple server socket program which sends some data in a loop and if the client is connected to the server socket(have done it with Arduino but need the same functionallity on raspberrypi or other sbc).
For example (arduino style):
EthernetServer server = EthernetServer(23);
// start listening for clients
server.begin();
int i = 0;
while(true){
i++;
EthernetClient client = server.available();
if (client) {
while (client.connected()) {
if (client.available()) {
client.print(i);
}
}
}
client.stop;
}
I have a SBC (single board computer) with GPIO buss. My program must:
read values from SPI bus (infinite loop)
if the client is connected to the server scoket It must send some values to the client.
I know how to implement this kind of app in Java but in C, I don't have enaugh knowledge.
I'am looking for some kind of library or example on how to implement it.
regards
You can refer below mentioned link to establish a client/server connection using sockets with RPi with C implementation. Hope it helps you.
http://cs.smith.edu/dftwiki/index.php/Tutorial:_Client/Server_on_the_Raspberry_Pi
I have several embedded machines listening and streaming rtp audio data to a multicast group. They are connected to a smart managed switch (Netgear GS108Ev2) which does basic igmp snooping and multicast filtering on its ports, so that the rest of my (W)LAN doesn't get flooded.
At start everything works fine for about 500-520 seconds. After that, they don't receive any more data until they leave and join the group again. I guess the switch is "forgetting" about the join after a timeout.
Is there any way to refresh the group membership, i.e. letting the switch know, that there ist still someone listening, without losing packets?
System info:
Arch: blackfin
# cat /proc/version
Linux version 2.6.28.10-ADI-2009R1-uCBF54x-EMM
(gcc version 4.3.3 (ADI) ) #158 PREEMPT Tue Jun 5 20:05:42 CEST 2012
This is the way multicast / the IGMP protocol works. A client has to join the group periodically by sending a Membership Report or it will be assumed that he has left the group after some short timeout. However, those reports are usually sent only when receiving a Membership Query from the local multicast router. Either your clients don't receive the query or don't respond with a report.
Try to use a tool like wireshark in order to see which IGMP packets are sent through your network.
You need an IGMP querier to send the Membership Queries, as was already explained by scai.
If you can't configure your router to do that, you can use one of your computers. Seeing how running a full multicast routing daemon would be overkill (and I've never done that), I suggest you try to abuse igmpproxy.
First create a dummy upstream interface (this is not persistent!):
ip tap add dev tap6 mode tap
Write igmpproxy.conf:
# Dummy upstream interface.
phyint tap6 upstream ratelimit 0 threshold 1
# Local interface.
phyint eth0 downstream ratelimit 0 threshold 1
# Explicitly disable any other interfaces (yes, it sucks).
phyint NAME disabled
...
Finally start igmpproxy (as root):
igmpproxy -v /path/to/igmpproxy.conf
If your embedded devices are running linux, you need to turn off the reverse packet filter on them or they won't respond to group membership queries. In that case the upstream switch will assume there is no-one listening to that multicast and switch it off.
I had same problem, multicast on wifi was lost after 260 seconds, I solved it with my application by adding AddSourceMembership on socket.
private void StartListner(IPAddress sourceIp, IPAddress multicastGroupIp, IPAddress localIp, int port)
{
try
{
Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
IPEndPoint localEndpoint = new IPEndPoint(localIp, port);
socket.Bind(localEndpoint);
byte[] membershipAddresses = new byte[12]; // 3 IPs * 4 bytes (IPv4)
Buffer.BlockCopy(multicastGroupIp.GetAddressBytes(), 0, membershipAddresses, 0, 4);
Buffer.BlockCopy(sourceIp.GetAddressBytes(), 0, membershipAddresses, 4, 4);
Buffer.BlockCopy(localIp.GetAddressBytes(), 0, membershipAddresses, 8, 4);
socket.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.AddSourceMembership, membershipAddresses);
try
{
byte[] b = new byte[1024 * 2];
int length = socket.Receive(b);
}
catch { }
}
catch (Exception ex)
{
logger.Error("Exception: " + ex);
}
}