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#include <dnswire/writer.h>
#include <arpa/inet.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <sys/un.h>
#include "create_dnstap.c"
int main(int argc, const char* argv[])
{
if (argc < 2) {
fprintf(stderr, "usage: sender [ <IP> <port> | <unix socket path> ]\n");
return 1;
}
/*
* We first initialize the writer and check that it can allocate the
* buffers it needs.
*/
struct dnswire_writer writer;
if (dnswire_writer_init(&writer) != dnswire_ok) {
fprintf(stderr, "Unable to initialize dnswire writer\n");
return 1;
}
/*
* Use bidirectional communication over the TCP or UNIX socket.
*/
if (dnswire_writer_set_bidirectional(&writer, true) != dnswire_ok) {
fprintf(stderr, "Unable to set dnswire writer to bidirectional mode\n");
return 1;
}
int sockfd;
if (argc == 2) {
/*
* We setup and connect to a unix socket at the given path on command line.
*/
struct sockaddr_un path;
memset(&path, 0, sizeof(struct sockaddr_un));
path.sun_family = AF_UNIX;
strncpy(path.sun_path, argv[1], sizeof(path.sun_path) - 1);
sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
if (sockfd == -1) {
fprintf(stderr, "socket() failed: %s\n", strerror(errno));
return 1;
}
printf("socket\n");
if (connect(sockfd, (struct sockaddr*)&path, sizeof(struct sockaddr_un))) {
fprintf(stderr, "connect() failed: %s\n", strerror(errno));
close(sockfd);
return 1;
}
printf("connect\n");
} else {
/*
* We setup and connect to the IP and port given on command line.
*/
struct sockaddr_storage addr_store;
struct sockaddr_in* addr = (struct sockaddr_in*)&addr_store;
socklen_t addrlen;
if (strchr(argv[1], ':')) {
addr->sin_family = AF_INET6;
addrlen = sizeof(struct sockaddr_in6);
} else {
addr->sin_family = AF_INET;
addrlen = sizeof(struct sockaddr_in);
}
if (inet_pton(addr->sin_family, argv[1], &addr->sin_addr) != 1) {
fprintf(stderr, "inet_pton(%s) failed: %s\n", argv[1], strerror(errno));
return 1;
}
addr->sin_port = ntohs(atoi(argv[2]));
sockfd = socket(addr->sin_family, SOCK_STREAM, IPPROTO_TCP);
if (sockfd == -1) {
fprintf(stderr, "socket() failed: %s\n", strerror(errno));
return 1;
}
printf("socket\n");
if (connect(sockfd, (struct sockaddr*)addr, addrlen)) {
fprintf(stderr, "connect() failed: %s\n", strerror(errno));
close(sockfd);
return 1;
}
printf("connect\n");
}
/*
* We are now connected!
*
* Now we create a DNSTAP message.
*/
struct dnstap d = create_dnstap("sender");
/*
* We set the DNSTAP message the writer should write.
*/
dnswire_writer_set_dnstap(writer, &d);
/*
* We now loop and wait for the DNSTAP message to be written.
*/
int done = 0;
printf("sending...\n");
while (!done) {
switch (dnswire_writer_write(&writer, sockfd)) {
case dnswire_ok:
/*
* The DNSTAP message was written successfully, we can now set
* a new DNSTAP message for the writer or stop the stream.
*
* This stops the stream, loop again until it's stopped.
*/
if (dnswire_writer_stop(&writer) != dnswire_ok) {
printf("stopping failed!\n");
done = 1;
}
break;
case dnswire_again:
/*
* This indicates that we need to call the writer again as it
* will only do one pass in a non-blocking fasion.
*/
break;
case dnswire_endofdata:
/*
* The stream is stopped, we're done!
*/
printf("stopped\n");
done = 1;
break;
default:
fprintf(stderr, "dnswire_writer_write() error\n");
done = 1;
}
}
dnswire_writer_destroy(writer);
/*
* Time to exit, let's shutdown and close the sockets.
*/
shutdown(sockfd, SHUT_RDWR);
close(sockfd);
return 0;
}
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