/* 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 "libbb.h"
- 19980918 Busy Boxed! Dave Cinege
- 19990512 Uses Select. Charles P. Wright
- 19990513 Fixes stdin stupidity and uses buffers. Charles P. Wright
+#if ENABLE_DESKTOP
+#include "nc_bloaty.c"
+#else
- 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.
+/* Lots of small differences in features
+ * when compared to "standard" nc
+ */
- 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 "busybox.h"
-#include <stdio.h>
-#include <stdlib.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>
+static void timeout(int signum UNUSED_PARAM)
+{
+ bb_error_msg_and_die("timed out");
+}
+int nc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int nc_main(int argc, char **argv)
{
- int sfd;
- char buf[BUFSIZ];
-
- struct sockaddr_in address;
- struct hostent *hostinfo;
-
+ /* sfd sits _here_ only because of "repeat" option (-l -l). */
+ int sfd = sfd; /* for gcc */
+ int cfd = 0;
+ unsigned lport = 0;
+ IF_NOT_NC_SERVER(const) unsigned do_listen = 0;
+ IF_NOT_NC_EXTRA (const) unsigned wsecs = 0;
+ IF_NOT_NC_EXTRA (const) unsigned delay = 0;
+ IF_NOT_NC_EXTRA (const int execparam = 0;)
+ IF_NC_EXTRA (char **execparam = NULL;)
fd_set readfds, testfds;
+ int opt; /* must be signed (getopt returns -1) */
+
+ if (ENABLE_NC_SERVER || ENABLE_NC_EXTRA) {
+ /* getopt32 is _almost_ usable:
+ ** it cannot handle "... -e prog -prog-opt" */
+ while ((opt = getopt(argc, argv,
+ "" IF_NC_SERVER("lp:") IF_NC_EXTRA("w:i:f:e:") )) > 0
+ ) {
+ if (ENABLE_NC_SERVER && opt == 'l')
+ IF_NC_SERVER(do_listen++);
+ else if (ENABLE_NC_SERVER && opt == 'p')
+ IF_NC_SERVER(lport = bb_lookup_port(optarg, "tcp", 0));
+ else if (ENABLE_NC_EXTRA && opt == 'w')
+ IF_NC_EXTRA( wsecs = xatou(optarg));
+ else if (ENABLE_NC_EXTRA && opt == 'i')
+ IF_NC_EXTRA( delay = xatou(optarg));
+ else if (ENABLE_NC_EXTRA && opt == 'f')
+ IF_NC_EXTRA( cfd = xopen(optarg, O_RDWR));
+ else if (ENABLE_NC_EXTRA && opt == 'e' && optind <= argc) {
+ /* We cannot just 'break'. We should let getopt finish.
+ ** Or else we won't be able to find where
+ ** 'host' and 'port' params are
+ ** (think "nc -w 60 host port -e prog"). */
+ IF_NC_EXTRA(
+ char **p;
+ // +2: one for progname (optarg) and one for NULL
+ execparam = xzalloc(sizeof(char*) * (argc - optind + 2));
+ p = execparam;
+ *p++ = optarg;
+ while (optind < argc) {
+ *p++ = argv[optind++];
+ }
+ )
+ /* optind points to argv[arvc] (NULL) now.
+ ** FIXME: we assume that getopt will not count options
+ ** possibly present on "-e prog args" and will not
+ ** include them into final value of optind
+ ** which is to be used ... */
+ } else bb_show_usage();
+ }
+ argv += optind; /* ... here! */
+ argc -= optind;
+ // -l and -f don't mix
+ if (do_listen && cfd) bb_show_usage();
+ // File mode needs need zero arguments, listen mode needs zero or one,
+ // client mode needs one or two
+ if (cfd) {
+ if (argc) bb_show_usage();
+ } else if (do_listen) {
+ if (argc > 1) bb_show_usage();
+ } else {
+ if (!argc || argc > 2) bb_show_usage();
+ }
+ } else {
+ if (argc != 3) bb_show_usage();
+ argc--;
+ argv++;
+ }
- argc--;
- argv++;
- if (argc < 2 || **argv == '-') {
- usage(nc_usage);
+ if (wsecs) {
+ signal(SIGALRM, timeout);
+ alarm(wsecs);
}
- if ((sfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
- perror_msg_and_die("socket");
+ if (!cfd) {
+ if (do_listen) {
+ sfd = create_and_bind_stream_or_die(argv[0], lport);
+ xlisten(sfd, do_listen); /* can be > 1 */
+#if 0 /* nc-1.10 does not do this (without -v) */
+ /* If we didn't specify a port number,
+ * query and print it after listen() */
+ if (!lport) {
+ len_and_sockaddr lsa;
+ lsa.len = LSA_SIZEOF_SA;
+ getsockname(sfd, &lsa.u.sa, &lsa.len);
+ lport = get_nport(&lsa.u.sa);
+ fdprintf(2, "%d\n", ntohs(lport));
+ }
+#endif
+ close_on_exec_on(sfd);
+ accept_again:
+ cfd = accept(sfd, NULL, 0);
+ if (cfd < 0)
+ bb_perror_msg_and_die("accept");
+ if (!execparam)
+ close(sfd);
+ } else {
+ cfd = create_and_connect_stream_or_die(argv[0],
+ argv[1] ? bb_lookup_port(argv[1], "tcp", 0) : 0);
+ }
+ }
- if ((hostinfo = gethostbyname(*argv)) == NULL)
- error_msg_and_die("cannot resolve %s\n", *argv);
+ if (wsecs) {
+ alarm(0);
+ /* Non-ignored signals revert to SIG_DFL on exec anyway */
+ /*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 (execparam) {
+ pid_t pid;
+ /* With more than one -l, repeatedly act as server */
+ if (do_listen > 1 && (pid = vfork()) != 0) {
+ /* parent or error */
+ if (pid < 0)
+ bb_perror_msg_and_die("vfork");
+ /* prevent zombies */
+ signal(SIGCHLD, SIG_IGN);
+ close(cfd);
+ goto accept_again;
+ }
+ /* child, or main thread if only one -l */
+ xmove_fd(cfd, 0);
+ xdup2(0, 1);
+ xdup2(0, 2);
+ IF_NC_EXTRA(BB_EXECVP(execparam[0], execparam);)
+ /* Don't print stuff or it will go over the wire... */
+ _exit(127);
+ }
- if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0)
- perror_msg_and_die("connect");
+ /* Select loop copying stdin to cfd, and cfd to stdout */
FD_ZERO(&readfds);
- FD_SET(sfd, &readfds);
+ FD_SET(cfd, &readfds);
FD_SET(STDIN_FILENO, &readfds);
- while (1) {
+ for (;;) {
int fd;
int ofd;
int nread;
testfds = readfds;
- if (select(FD_SETSIZE, &testfds, NULL, NULL, NULL) < 0)
- perror_msg_and_die("select");
+ if (select(cfd + 1, &testfds, NULL, NULL, NULL) < 0)
+ bb_perror_msg_and_die("select");
- for (fd = 0; fd < FD_SETSIZE; fd++) {
+#define iobuf bb_common_bufsiz1
+ fd = STDIN_FILENO;
+ while (1) {
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);
+ nread = safe_read(fd, iobuf, sizeof(iobuf));
+ if (fd == cfd) {
+ if (nread < 1)
+ exit(EXIT_SUCCESS);
ofd = STDOUT_FILENO;
} else {
- if (nread == 0)
- shutdown(sfd, 1);
- 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;
}
-
- if (full_write(ofd, buf, nread) < 0)
- perror_msg_and_die("write");
+ xwrite(ofd, iobuf, nread);
+ if (delay > 0)
+ sleep(delay);
}
+ if (fd == cfd)
+ break;
+ fd = cfd;
}
}
}
+#endif