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#include <dnswire/reader.h>
#include <stdio.h>
#include <errno.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/un.h>
#include "print_dnstap.c"
int main(int argc, const char* argv[])
{
if (argc < 2) {
fprintf(stderr, "usage: receiver [ <IP> <port> | <unix socket path> ]\n");
return 1;
}
/*
* We first initialize the reader and check that it can allocate the
* buffers it needs.
*/
struct dnswire_reader reader;
if (dnswire_reader_init(&reader) != dnswire_ok) {
fprintf(stderr, "Unable to initialize dnswire reader\n");
return 1;
}
/*
* Allow bidirectional communication over the TCP or UNIX socket.
*/
if (dnswire_reader_allow_bidirectional(&reader, true) != dnswire_ok) {
fprintf(stderr, "Unable to set dnswire reader to bidirectional mode\n");
return 1;
}
int sockfd;
if (argc == 2) {
/*
* We setup 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 (bind(sockfd, (struct sockaddr*)&path, sizeof(struct sockaddr_un))) {
fprintf(stderr, "bind() failed: %s\n", strerror(errno));
close(sockfd);
return 1;
}
printf("bind\n");
} else {
/*
* We setup and listen on 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 (bind(sockfd, (struct sockaddr*)addr, addrlen)) {
fprintf(stderr, "bind() failed: %s\n", strerror(errno));
close(sockfd);
return 1;
}
printf("bind\n");
}
if (listen(sockfd, 1)) {
fprintf(stderr, "listen() failed: %s\n", strerror(errno));
close(sockfd);
return 1;
}
printf("listen\n");
int clifd = accept(sockfd, 0, 0);
if (clifd < 0) {
fprintf(stderr, "accept() failed: %s\n", strerror(errno));
close(sockfd);
return 1;
}
printf("accept\n");
/*
* We have accepted connection from the sender!
*
* We now loop until we have a DNSTAP message, the stream was stopped
* or we got an error.
*/
int done = 0;
printf("receiving...\n");
while (!done) {
switch (dnswire_reader_read(&reader, clifd)) {
case dnswire_have_dnstap:
/*
* We received a DNSTAP message, let's print it.
*/
print_dnstap(dnswire_reader_dnstap(reader));
break;
case dnswire_again:
case dnswire_need_more:
/*
* This indicates that we need to call the reader again as it
* will only do one pass in a non-blocking fasion.
*/
break;
case dnswire_endofdata:
/*
* The stream was stopped from the sender side, we're done!
*/
printf("stopped\n");
done = 1;
break;
default:
fprintf(stderr, "dnswire_reader_read() error\n");
done = 1;
}
}
dnswire_reader_destroy(reader);
/*
* Time to exit, let's shutdown and close the sockets.
*/
shutdown(clifd, SHUT_RDWR);
close(clifd);
close(sockfd);
return 0;
}
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