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#include <sys/types.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h>
#include "proxy.h"
static int parse_host(const char *host, const char *port, struct addrinfo **addr)
{
struct addrinfo hints = {
.ai_family = AF_UNSPEC,
.ai_socktype = SOCK_STREAM,
.ai_flags = AI_PASSIVE,
};
int err;
if ((err = getaddrinfo(host, port, &hints, addr))) {
fprintf(stderr, "getaddrinfo failed: %s\n", gai_strerror(err));
return -1;
}
return 0;
}
static int listen_source(struct addrinfo *source)
{
int fd = -1;
for (struct addrinfo *a = source; a; a = a->ai_next) {
if ((fd = socket(a->ai_family, a->ai_socktype, a->ai_protocol)) == -1)
continue;
if (!bind(fd, a->ai_addr, a->ai_addrlen) && !listen(fd, 1))
break;
close(fd);
fd = -1;
}
return fd;
}
static int connect_target(struct addrinfo *target)
{
int fd = -1;
for (struct addrinfo *a = target; a; a = a->ai_next) {
if ((fd = socket(a->ai_family, a->ai_socktype, a->ai_protocol)) == -1)
continue;
if (connect(fd, a->ai_addr, a->ai_addrlen) != -1)
break;
close(fd);
fd = -1;
}
return fd;
}
int main(int argc, char **argv)
{
struct addrinfo *source;
struct addrinfo *target;
if (argc != 3) {
fprintf(stderr, "usage: %s targethost targetport\n", argv[0]);
return -1;
}
if (parse_host(NULL, "1234", &source))
return -1;
if (parse_host(argv[1], argv[2], &target))
return -1;
int listenfd = listen_source(source);
if (listenfd < 0) {
perror("listen_source");
return -1;
}
for (;;) {
int sourcefd = accept(listenfd, NULL, NULL);
if (sourcefd == -1) break;
int targetfd = connect_target(target);
if (targetfd == -1) {
perror("connect_target");
close(sourcefd);
break;
}
proxy(sourcefd, targetfd, 500);
close(targetfd);
close(sourcefd);
}
close(listenfd);
return 0;
}
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