/* vi: set sw=4 ts=4: */
/* nc: mini-netcat - built from the ground up for LRP
- Copyright (C) 1998 Charles P. Wright
+ *
+ * Copyright (C) 1998, 1999 Charles P. Wright
+ * Copyright (C) 1998 Dave Cinege
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
- 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()
+#include "busybox.h"
- 19980918 Busy Boxed! Dave Cinege
- 19990512 Uses Select. Charles P. Wright
- 19990513 Fixes stdin stupidity and uses buffers. Charles P. Wright
+static void timeout(int signum)
+{
+ bb_error_msg_and_die("Timed out");
+}
- 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.
+int nc_main(int argc, char **argv)
+{
+ int do_listen = 0, lport = 0, delay = 0, wsecs = 0, execflag = 0, opt,
+ sfd = 0, cfd;
+ struct sockaddr_in address;
+ struct hostent *hostinfo;
+ fd_set readfds, testfds;
+ char *infile = NULL;
+
+ memset(&address, 0, sizeof(address));
+
+ if (ENABLE_NC_SERVER || ENABLE_NC_EXTRA) {
+ while ((opt = getopt(argc, argv, "lp:" USE_NC_EXTRA("i:ew:f:"))) > 0) {
+ if (ENABLE_NC_SERVER && opt=='l') do_listen++;
+ else if (ENABLE_NC_SERVER && opt=='p')
+ lport = bb_lookup_port(optarg, "tcp", 0);
+ else if (ENABLE_NC_EXTRA && opt=='w') wsecs = atoi(optarg);
+ else if (ENABLE_NC_EXTRA && opt=='i') delay = atoi(optarg);
+ else if (ENABLE_NC_EXTRA && opt=='f') infile = optarg;
+ else if (ENABLE_NC_EXTRA && opt=='e' && optind!=argc) {
+ execflag++;
+ break;
+ } else bb_show_usage();
+ }
+ }
- 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.
+
+ // For listen or file we need zero arguments, dialout is 2.
+ // For exec we need at least one more argument at the end, more ok
- 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.
+ opt = (do_listen || infile) ? 0 : 2 + execflag;
+ if (execflag ? argc-optind < opt : argc-optind!=opt ||
+ (infile && do_listen))
+ bb_show_usage();
-*/
-#include "busybox.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
+ if (wsecs) {
+ signal(SIGALRM, timeout);
+ alarm(wsecs);
+ }
+
+ if (infile) cfd = xopen(infile, O_RDWR);
+ else {
+ opt = 1;
+ sfd = xsocket(AF_INET, SOCK_STREAM, 0);
+ fcntl(sfd, F_SETFD, FD_CLOEXEC);
+ setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof (opt));
+ address.sin_family = AF_INET;
-#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>
+ // Set local port.
-#define BUFSIZE 100
+ if (lport != 0) {
+ address.sin_port = lport;
-int nc_main(int argc, char **argv)
-{
- int sfd;
- int result;
- int len;
- char ch[BUFSIZE];
+ xbind(sfd, (struct sockaddr *) &address, sizeof(address));
+ }
- struct sockaddr_in address;
- struct hostent *hostinfo;
+ if (do_listen) {
+ socklen_t addrlen = sizeof(address);
- fd_set readfds, testfds;
+ xlisten(sfd, do_listen);
- argc--;
- argv++;
- if (argc < 2 || **(argv + 1) == '-') {
- usage(nc_usage);
- }
+ // If we didn't specify a port number, query and print it to stderr.
+
+ if (!lport) {
+ socklen_t len = sizeof(address);
+ getsockname(sfd, &address, &len);
+ fdprintf(2, "%d\n", SWAP_BE16(address.sin_port));
+ }
+repeatyness:
+ if ((cfd = accept(sfd, (struct sockaddr *) &address, &addrlen)) < 0)
+ bb_perror_msg_and_die("accept");
+
+ if (!execflag) close(sfd);
+ } else {
+ hostinfo = xgethostbyname(argv[optind]);
- sfd = socket(AF_INET, SOCK_STREAM, 0);
+ address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list;
+ address.sin_port = bb_lookup_port(argv[optind+1], "tcp", 0);
- hostinfo = (struct hostent *) gethostbyname(*argv);
+ if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
+ bb_perror_msg_and_die("connect");
+ cfd = sfd;
+ }
+ }
- if (!hostinfo) {
- fatalError("cannot resolve %s\n", *argv);
+ if (wsecs) {
+ alarm(0);
+ signal(SIGALRM, SIG_DFL);
}
- address.sin_family = AF_INET;
- address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list;
- address.sin_port = htons(atoi(*(++argv)));
+ /* -e given? */
+ if (execflag) {
+ if(cfd) {
+ signal(SIGCHLD, SIG_IGN);
+ dup2(cfd, 0);
+ close(cfd);
+ }
+ dup2(0, 1);
+ dup2(0, 2);
- len = sizeof(address);
+ // With more than one -l, repeatedly act as server.
- result = connect(sfd, (struct sockaddr *) &address, len);
+ if (do_listen>1 && vfork()) {
+ // This is a bit weird as cleanup goes, since we wind up with no
+ // stdin/stdout/stderr. But it's small and shouldn't hurt anything.
+ // We check for cfd == 0 above.
+ close(0);
+ close(1);
+ close(2);
- if (result < 0) {
- perror("nc: connect");
- exit(2);
+ goto repeatyness;
+ }
+ execvp(argv[optind], argv+optind);
+ /* Don't print stuff or it will go over the wire.... */
+ _exit(127);
}
+ // Select loop copying stdin to cfd, and cfd to stdout.
+
FD_ZERO(&readfds);
- FD_SET(sfd, &readfds);
- FD_SET(fileno(stdin), &readfds);
+ FD_SET(cfd, &readfds);
+ FD_SET(STDIN_FILENO, &readfds);
- while (1) {
+ for (;;) {
int fd;
int ofd;
int nread;
testfds = readfds;
- result =
- select(FD_SETSIZE, &testfds, (fd_set *) NULL, (fd_set *) NULL,
- (struct timeval *) 0);
-
- if (result < 1) {
- perror("nc: select");
- exit(3);
- }
+ if (select(FD_SETSIZE, &testfds, NULL, NULL, NULL) < 0)
+ bb_perror_msg_and_die("select");
for (fd = 0; fd < FD_SETSIZE; fd++) {
if (FD_ISSET(fd, &testfds)) {
- int trn = 0;
- int rn;
+ nread = safe_read(fd, bb_common_bufsiz1,
+ sizeof(bb_common_bufsiz1));
- ioctl(fd, FIONREAD, &nread);
-
- if (fd == sfd) {
- if (nread == 0)
- exit(0);
- ofd = fileno(stdout);
+ if (fd == cfd) {
+ if (nread<1) exit(0);
+ ofd = STDOUT_FILENO;
} else {
- ofd = sfd;
+ if (nread<1) {
+ // Close outgoing half-connection so they get EOF, but
+ // leave incoming alone so we can see response.
+ shutdown(cfd, 1);
+ FD_CLR(STDIN_FILENO, &readfds);
+ }
+ ofd = cfd;
}
-
-
- do {
- rn = (BUFSIZE < nread - trn) ? BUFSIZE : nread - trn;
- trn += rn;
- read(fd, ch, rn);
- write(ofd, ch, rn);
- }
- while (trn < nread);
+ xwrite(ofd, bb_common_bufsiz1, nread);
+ if (delay > 0) sleep(delay);
}
}
}
projects / oweals / busybox.git / blobdiff