138 lines
3.3 KiB
C
138 lines
3.3 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/* nc: mini-netcat - built from the ground up for LRP
|
|
Copyright (C) 1998 Charles P. Wright
|
|
|
|
0.0.1 6K It works.
|
|
0.0.2 5K Smaller and you can also check the exit condition if you wish.
|
|
0.0.3 Uses select()
|
|
|
|
19980918 Busy Boxed! Dave Cinege
|
|
19990512 Uses Select. Charles P. Wright
|
|
19990513 Fixes stdin stupidity and uses buffers. Charles P. Wright
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/socket.h>
|
|
#include <netinet/in.h>
|
|
#include <arpa/inet.h>
|
|
#include <netdb.h>
|
|
#include <sys/time.h>
|
|
#include <sys/ioctl.h>
|
|
#include "busybox.h"
|
|
|
|
int nc_main(int argc, char **argv)
|
|
{
|
|
int do_listen = 0, lport = 0, tmpfd, opt, sfd;
|
|
char buf[BUFSIZ];
|
|
|
|
struct sockaddr_in address;
|
|
struct hostent *hostinfo;
|
|
|
|
fd_set readfds, testfds;
|
|
|
|
while ((opt = getopt(argc, argv, "lp:")) > 0) {
|
|
switch (opt) {
|
|
case 'l':
|
|
do_listen++;
|
|
break;
|
|
case 'p':
|
|
lport = atoi(optarg);
|
|
break;
|
|
default:
|
|
show_usage();
|
|
}
|
|
}
|
|
|
|
if ((do_listen && optind != argc) || (!do_listen && optind + 2 != argc))
|
|
show_usage();
|
|
|
|
if ((sfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
|
|
perror_msg_and_die("socket");
|
|
|
|
address.sin_family = AF_INET;
|
|
|
|
if (lport != 0) {
|
|
memset(&address.sin_addr, 0, sizeof(address.sin_addr));
|
|
address.sin_port = htons(lport);
|
|
|
|
if (bind(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
|
|
perror_msg_and_die("bind");
|
|
}
|
|
|
|
if (do_listen) {
|
|
socklen_t addrlen = sizeof(address);
|
|
|
|
if (listen(sfd, 1) < 0)
|
|
perror_msg_and_die("listen");
|
|
|
|
if ((tmpfd = accept(sfd, (struct sockaddr *) &address, &addrlen)) < 0)
|
|
perror_msg_and_die("accept");
|
|
|
|
close(sfd);
|
|
sfd = tmpfd;
|
|
} else {
|
|
hostinfo = xgethostbyname(argv[optind]);
|
|
|
|
address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list;
|
|
address.sin_port = htons(atoi(argv[optind+1]));
|
|
|
|
if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
|
|
perror_msg_and_die("connect");
|
|
}
|
|
|
|
FD_ZERO(&readfds);
|
|
FD_SET(sfd, &readfds);
|
|
FD_SET(STDIN_FILENO, &readfds);
|
|
|
|
while (1) {
|
|
int fd;
|
|
int ofd;
|
|
int nread;
|
|
|
|
testfds = readfds;
|
|
|
|
if (select(FD_SETSIZE, &testfds, NULL, NULL, NULL) < 0)
|
|
perror_msg_and_die("select");
|
|
|
|
for (fd = 0; fd < FD_SETSIZE; fd++) {
|
|
if (FD_ISSET(fd, &testfds)) {
|
|
if ((nread = safe_read(fd, buf, sizeof(buf))) < 0)
|
|
perror_msg_and_die("read");
|
|
|
|
if (fd == sfd) {
|
|
if (nread == 0)
|
|
exit(0);
|
|
ofd = STDOUT_FILENO;
|
|
} else {
|
|
if (nread == 0)
|
|
shutdown(sfd, 1);
|
|
ofd = sfd;
|
|
}
|
|
|
|
if (full_write(ofd, buf, nread) < 0)
|
|
perror_msg_and_die("write");
|
|
}
|
|
}
|
|
}
|
|
}
|