From 1d7026745028982980d17b1023c4ce8ec97ea946 Mon Sep 17 00:00:00 2001 From: Matt Kraai Date: Wed, 7 Feb 2001 04:09:23 +0000 Subject: [PATCH] Add listening support. --- applets/usage.c | 8 +++++-- docs/busybox.sgml | 7 +++++- nc.c | 54 ++++++++++++++++++++++++++++++++++++----------- networking/nc.c | 54 ++++++++++++++++++++++++++++++++++++----------- usage.c | 8 +++++-- 5 files changed, 102 insertions(+), 29 deletions(-) diff --git a/applets/usage.c b/applets/usage.c index 215871b5a..1686910d5 100644 --- a/applets/usage.c +++ b/applets/usage.c @@ -959,9 +959,13 @@ const char mv_usage[] = #if defined BB_NC const char nc_usage[] = - "nc [IP] [port]" + "nc [-p PORT] IP PORT\n" + " or: nc -l -p PORT" #ifndef BB_FEATURE_TRIVIAL_HELP - "\n\nNetcat opens a pipe to IP:port" + "\n\nNetcat opens a pipe to IP:PORT\n" + "Options:\n" + "\t-l\tListen on the socket.\n" + "\t-p PORT\tBind the local port to PORT." #endif ; #endif diff --git a/docs/busybox.sgml b/docs/busybox.sgml index 0dc4bffa3..02d85e499 100644 --- a/docs/busybox.sgml +++ b/docs/busybox.sgml @@ -2452,7 +2452,12 @@ - Open a pipe to HOST:PORT. + or: nc -p PORT -l + + + + + Open a pipe to HOST:PORT or listen for a connection on PORT. diff --git a/nc.c b/nc.c index 682da82bf..3f512d1cb 100644 --- a/nc.c +++ b/nc.c @@ -41,7 +41,7 @@ int nc_main(int argc, char **argv) { - int sfd; + int do_listen = 0, lport = 0, tmpfd, opt, sfd; char buf[BUFSIZ]; struct sockaddr_in address; @@ -49,24 +49,54 @@ int nc_main(int argc, char **argv) fd_set readfds, testfds; - argc--; - argv++; - if (argc < 2 || **argv == '-') { - usage(nc_usage); + while ((opt = getopt(argc, argv, "lp:")) > 0) { + switch (opt) { + case 'l': + do_listen++; + break; + case 'p': + lport = atoi(optarg); + break; + default: + usage(nc_usage); + } } + if ((do_listen && optind != argc) || (!do_listen && optind + 2 != argc)) + usage(nc_usage); + if ((sfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) perror_msg_and_die("socket"); - if ((hostinfo = gethostbyname(*argv)) == NULL) - error_msg_and_die("cannot resolve %s", *argv); - address.sin_family = AF_INET; - address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list; - address.sin_port = htons(atoi(*(++argv))); - if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0) - perror_msg_and_die("connect"); + 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) { + if (listen(sfd, 1) < 0) + perror_msg_and_die("listen"); + + if ((tmpfd = accept(sfd, (struct sockaddr *) &address, &opt)) < 0) + perror_msg_and_die("accept"); + + close(sfd); + sfd = tmpfd; + } else { + if ((hostinfo = gethostbyname(argv[optind])) == NULL) + error_msg_and_die("cannot resolve %s\n", 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); diff --git a/networking/nc.c b/networking/nc.c index 682da82bf..3f512d1cb 100644 --- a/networking/nc.c +++ b/networking/nc.c @@ -41,7 +41,7 @@ int nc_main(int argc, char **argv) { - int sfd; + int do_listen = 0, lport = 0, tmpfd, opt, sfd; char buf[BUFSIZ]; struct sockaddr_in address; @@ -49,24 +49,54 @@ int nc_main(int argc, char **argv) fd_set readfds, testfds; - argc--; - argv++; - if (argc < 2 || **argv == '-') { - usage(nc_usage); + while ((opt = getopt(argc, argv, "lp:")) > 0) { + switch (opt) { + case 'l': + do_listen++; + break; + case 'p': + lport = atoi(optarg); + break; + default: + usage(nc_usage); + } } + if ((do_listen && optind != argc) || (!do_listen && optind + 2 != argc)) + usage(nc_usage); + if ((sfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) perror_msg_and_die("socket"); - if ((hostinfo = gethostbyname(*argv)) == NULL) - error_msg_and_die("cannot resolve %s", *argv); - address.sin_family = AF_INET; - address.sin_addr = *(struct in_addr *) *hostinfo->h_addr_list; - address.sin_port = htons(atoi(*(++argv))); - if (connect(sfd, (struct sockaddr *) &address, sizeof(address)) < 0) - perror_msg_and_die("connect"); + 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) { + if (listen(sfd, 1) < 0) + perror_msg_and_die("listen"); + + if ((tmpfd = accept(sfd, (struct sockaddr *) &address, &opt)) < 0) + perror_msg_and_die("accept"); + + close(sfd); + sfd = tmpfd; + } else { + if ((hostinfo = gethostbyname(argv[optind])) == NULL) + error_msg_and_die("cannot resolve %s\n", 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); diff --git a/usage.c b/usage.c index 215871b5a..1686910d5 100644 --- a/usage.c +++ b/usage.c @@ -959,9 +959,13 @@ const char mv_usage[] = #if defined BB_NC const char nc_usage[] = - "nc [IP] [port]" + "nc [-p PORT] IP PORT\n" + " or: nc -l -p PORT" #ifndef BB_FEATURE_TRIVIAL_HELP - "\n\nNetcat opens a pipe to IP:port" + "\n\nNetcat opens a pipe to IP:PORT\n" + "Options:\n" + "\t-l\tListen on the socket.\n" + "\t-p PORT\tBind the local port to PORT." #endif ; #endif