blob: b2f590adf42c0528b5f7d5332755cab2a5768b10 [file] [log] [blame]
Erik Andersene49d5ec2000-02-08 19:58:47 +00001/* vi: set sw=4 ts=4: */
Erik Andersen7ab9c7e2000-05-12 19:41:47 +00002/* nc: mini-netcat - built from the ground up for LRP
Denis Vlasenko9213a9e2006-09-17 16:28:10 +00003 *
Rob Landley1cca9482006-07-10 19:45:20 +00004 * Copyright (C) 1998, 1999 Charles P. Wright
5 * Copyright (C) 1998 Dave Cinege
Denis Vlasenko9213a9e2006-09-17 16:28:10 +00006 *
Rob Landley1cca9482006-07-10 19:45:20 +00007 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
8 */
Eric Andersencc8ed391999-10-05 16:24:54 +00009
Denis Vlasenkob6adbf12007-05-26 19:00:18 +000010#include "libbb.h"
Eric Andersencc8ed391999-10-05 16:24:54 +000011
Denis Vlasenko29fe7262007-04-05 20:26:28 +000012#if ENABLE_DESKTOP
13#include "nc_bloaty.c"
14#else
15
Denis Vlasenko5d687242007-01-12 20:59:31 +000016/* Lots of small differences in features
17 * when compared to "standard" nc
18 */
19
Mike Frysinger60a5c382005-05-06 04:45:38 +000020static void timeout(int signum)
21{
Denis Vlasenko13858992006-10-08 12:49:22 +000022 bb_error_msg_and_die("timed out");
Mike Frysinger60a5c382005-05-06 04:45:38 +000023}
24
Denis Vlasenko9b49a5e2007-10-11 10:05:36 +000025int nc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
Erik Andersen7ab9c7e2000-05-12 19:41:47 +000026int nc_main(int argc, char **argv)
Eric Andersencc8ed391999-10-05 16:24:54 +000027{
Denis Vlasenko5d687242007-01-12 20:59:31 +000028 /* sfd sits _here_ only because of "repeat" option (-l -l). */
29 int sfd = sfd; /* for gcc */
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000030 int cfd = 0;
Denis Vlasenko31635552007-01-20 16:54:19 +000031 unsigned lport = 0;
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000032 SKIP_NC_SERVER(const) unsigned do_listen = 0;
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000033 SKIP_NC_EXTRA (const) unsigned wsecs = 0;
34 SKIP_NC_EXTRA (const) unsigned delay = 0;
35 SKIP_NC_EXTRA (const int execparam = 0;)
36 USE_NC_EXTRA (char **execparam = NULL;)
Denis Vlasenko5d687242007-01-12 20:59:31 +000037 len_and_sockaddr *lsa;
Erik Andersene49d5ec2000-02-08 19:58:47 +000038 fd_set readfds, testfds;
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000039 int opt; /* must be signed (getopt returns -1) */
Erik Andersene49d5ec2000-02-08 19:58:47 +000040
Denis Vlasenko9213a9e2006-09-17 16:28:10 +000041 if (ENABLE_NC_SERVER || ENABLE_NC_EXTRA) {
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000042 /* getopt32 is _almost_ usable:
43 ** it cannot handle "... -e prog -prog-opt" */
44 while ((opt = getopt(argc, argv,
45 "" USE_NC_SERVER("lp:") USE_NC_EXTRA("w:i:f:e:") )) > 0
46 ) {
47 if (ENABLE_NC_SERVER && opt=='l') USE_NC_SERVER(do_listen++);
Denis Vlasenko6536a9b2007-01-12 10:35:23 +000048 else if (ENABLE_NC_SERVER && opt=='p') {
49 USE_NC_SERVER(lport = bb_lookup_port(optarg, "tcp", 0));
Denis Vlasenko6536a9b2007-01-12 10:35:23 +000050 }
Denis Vlasenko703e2022007-01-22 14:12:08 +000051 else if (ENABLE_NC_EXTRA && opt=='w') USE_NC_EXTRA( wsecs = xatou(optarg));
52 else if (ENABLE_NC_EXTRA && opt=='i') USE_NC_EXTRA( delay = xatou(optarg));
53 else if (ENABLE_NC_EXTRA && opt=='f') USE_NC_EXTRA( cfd = xopen(optarg, O_RDWR));
54 else if (ENABLE_NC_EXTRA && opt=='e' && optind<=argc) {
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000055 /* We cannot just 'break'. We should let getopt finish.
56 ** Or else we won't be able to find where
57 ** 'host' and 'port' params are
58 ** (think "nc -w 60 host port -e prog"). */
59 USE_NC_EXTRA(
60 char **p;
61 // +2: one for progname (optarg) and one for NULL
62 execparam = xzalloc(sizeof(char*) * (argc - optind + 2));
63 p = execparam;
64 *p++ = optarg;
65 while (optind < argc) {
66 *p++ = argv[optind++];
67 }
68 )
69 /* optind points to argv[arvc] (NULL) now.
70 ** FIXME: we assume that getopt will not count options
71 ** possibly present on "-e prog args" and will not
72 ** include them into final value of optind
73 ** which is to be used ... */
Rob Landley1cca9482006-07-10 19:45:20 +000074 } else bb_show_usage();
Matt Kraai1d702672001-02-07 04:09:23 +000075 }
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000076 argv += optind; /* ... here! */
77 argc -= optind;
78 // -l and -f don't mix
79 if (do_listen && cfd) bb_show_usage();
80 // Listen or file modes need zero arguments, client mode needs 2
Denis Vlasenko5d687242007-01-12 20:59:31 +000081 if (do_listen || cfd) {
82 if (argc) bb_show_usage();
83 } else {
84 if (!argc || argc > 2) bb_show_usage();
85 }
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000086 } else {
87 if (argc != 3) bb_show_usage();
88 argc--;
89 argv++;
90 }
Eric Andersencc8ed391999-10-05 16:24:54 +000091
Mike Frysinger60a5c382005-05-06 04:45:38 +000092 if (wsecs) {
93 signal(SIGALRM, timeout);
94 alarm(wsecs);
95 }
Denis Vlasenko9213a9e2006-09-17 16:28:10 +000096
Denis Vlasenkod0e70af2006-10-16 01:10:28 +000097 if (!cfd) {
Rob Landley1cca9482006-07-10 19:45:20 +000098 if (do_listen) {
Denis Vlasenko5d687242007-01-12 20:59:31 +000099 /* create_and_bind_stream_or_die(NULL, lport)
100 * would've work wonderfully, but we need
101 * to know lsa */
102 sfd = xsocket_stream(&lsa);
103 if (lport)
104 set_nport(lsa, htons(lport));
105 setsockopt_reuseaddr(sfd);
106 xbind(sfd, &lsa->sa, lsa->len);
107 xlisten(sfd, do_listen); /* can be > 1 */
108 /* If we didn't specify a port number,
109 * query and print it after listen() */
Rob Landley1cca9482006-07-10 19:45:20 +0000110 if (!lport) {
Denis Vlasenko703e2022007-01-22 14:12:08 +0000111 socklen_t addrlen = lsa->len;
Denis Vlasenko5d687242007-01-12 20:59:31 +0000112 getsockname(sfd, &lsa->sa, &addrlen);
Denis Vlasenko2856dab2007-04-01 01:18:20 +0000113 lport = get_nport(&lsa->sa);
Denis Vlasenko5d687242007-01-12 20:59:31 +0000114 fdprintf(2, "%d\n", ntohs(lport));
Rob Landley1cca9482006-07-10 19:45:20 +0000115 }
Denis Vlasenko96e1b382007-09-30 23:50:48 +0000116 close_on_exec_on(sfd);
Denis Vlasenko5d687242007-01-12 20:59:31 +0000117 accept_again:
Denis Vlasenko703e2022007-01-22 14:12:08 +0000118 cfd = accept(sfd, NULL, 0);
Denis Vlasenko13858992006-10-08 12:49:22 +0000119 if (cfd < 0)
Rob Landley1cca9482006-07-10 19:45:20 +0000120 bb_perror_msg_and_die("accept");
Denis Vlasenko5d687242007-01-12 20:59:31 +0000121 if (!execparam)
122 close(sfd);
Rob Landley1cca9482006-07-10 19:45:20 +0000123 } else {
Denis Vlasenko5d687242007-01-12 20:59:31 +0000124 cfd = create_and_connect_stream_or_die(argv[0],
125 argv[1] ? bb_lookup_port(argv[1], "tcp", 0) : 0);
Rob Landley1cca9482006-07-10 19:45:20 +0000126 }
Matt Kraai1d702672001-02-07 04:09:23 +0000127 }
Eric Andersencc8ed391999-10-05 16:24:54 +0000128
Mike Frysinger60a5c382005-05-06 04:45:38 +0000129 if (wsecs) {
130 alarm(0);
131 signal(SIGALRM, SIG_DFL);
132 }
133
Eric Andersen1323c942002-04-26 23:59:12 +0000134 /* -e given? */
Denis Vlasenkod0e70af2006-10-16 01:10:28 +0000135 if (execparam) {
Denis Vlasenko5d687242007-01-12 20:59:31 +0000136 signal(SIGCHLD, SIG_IGN);
Rob Landley1cca9482006-07-10 19:45:20 +0000137 // With more than one -l, repeatedly act as server.
Denis Vlasenko13858992006-10-08 12:49:22 +0000138 if (do_listen > 1 && vfork()) {
Denis Vlasenko5d687242007-01-12 20:59:31 +0000139 /* parent */
Rob Landley1cca9482006-07-10 19:45:20 +0000140 // This is a bit weird as cleanup goes, since we wind up with no
141 // stdin/stdout/stderr. But it's small and shouldn't hurt anything.
142 // We check for cfd == 0 above.
Denis Vlasenko13858992006-10-08 12:49:22 +0000143 logmode = LOGMODE_NONE;
Rob Landley1cca9482006-07-10 19:45:20 +0000144 close(0);
145 close(1);
146 close(2);
Denis Vlasenko5d687242007-01-12 20:59:31 +0000147 goto accept_again;
Rob Landley1cca9482006-07-10 19:45:20 +0000148 }
Denis Vlasenko5d687242007-01-12 20:59:31 +0000149 /* child (or main thread if no multiple -l) */
150 if (cfd) {
151 dup2(cfd, 0);
152 close(cfd);
153 }
154 dup2(0, 1);
155 dup2(0, 2);
Denis Vlasenko1d76f432007-02-06 01:20:12 +0000156 USE_NC_EXTRA(BB_EXECVP(execparam[0], execparam);)
Rob Landley1cca9482006-07-10 19:45:20 +0000157 /* Don't print stuff or it will go over the wire.... */
158 _exit(127);
159 }
160
161 // Select loop copying stdin to cfd, and cfd to stdout.
Denis Vlasenko9213a9e2006-09-17 16:28:10 +0000162
Erik Andersene49d5ec2000-02-08 19:58:47 +0000163 FD_ZERO(&readfds);
Rob Landley1cca9482006-07-10 19:45:20 +0000164 FD_SET(cfd, &readfds);
Matt Kraaibfa79672000-12-15 22:34:34 +0000165 FD_SET(STDIN_FILENO, &readfds);
Eric Andersencc8ed391999-10-05 16:24:54 +0000166
Rob Landley1cca9482006-07-10 19:45:20 +0000167 for (;;) {
Erik Andersene49d5ec2000-02-08 19:58:47 +0000168 int fd;
Eric Andersen2ce1edc1999-10-12 15:42:48 +0000169 int ofd;
Erik Andersene49d5ec2000-02-08 19:58:47 +0000170 int nread;
Eric Andersencc8ed391999-10-05 16:24:54 +0000171
Erik Andersene49d5ec2000-02-08 19:58:47 +0000172 testfds = readfds;
Eric Andersencc8ed391999-10-05 16:24:54 +0000173
Matt Kraaibfa79672000-12-15 22:34:34 +0000174 if (select(FD_SETSIZE, &testfds, NULL, NULL, NULL) < 0)
Manuel Novoa III cad53642003-03-19 09:13:01 +0000175 bb_perror_msg_and_die("select");
Eric Andersencc8ed391999-10-05 16:24:54 +0000176
Denis Vlasenko74324c82007-06-04 10:16:52 +0000177#define iobuf bb_common_bufsiz1
Erik Andersene49d5ec2000-02-08 19:58:47 +0000178 for (fd = 0; fd < FD_SETSIZE; fd++) {
179 if (FD_ISSET(fd, &testfds)) {
Denis Vlasenko74324c82007-06-04 10:16:52 +0000180 nread = safe_read(fd, iobuf, sizeof(iobuf));
Rob Landley1cca9482006-07-10 19:45:20 +0000181 if (fd == cfd) {
Denis Vlasenko5d687242007-01-12 20:59:31 +0000182 if (nread < 1)
183 exit(0);
Matt Kraaibfa79672000-12-15 22:34:34 +0000184 ofd = STDOUT_FILENO;
Erik Andersene49d5ec2000-02-08 19:58:47 +0000185 } else {
Rob Landley53437472006-07-16 08:14:35 +0000186 if (nread<1) {
Rob Landley1cca9482006-07-10 19:45:20 +0000187 // Close outgoing half-connection so they get EOF, but
188 // leave incoming alone so we can see response.
189 shutdown(cfd, 1);
Paul Fox7b71d742005-07-18 22:23:16 +0000190 FD_CLR(STDIN_FILENO, &readfds);
191 }
Rob Landley1cca9482006-07-10 19:45:20 +0000192 ofd = cfd;
Eric Andersen2ce1edc1999-10-12 15:42:48 +0000193 }
Denis Vlasenko74324c82007-06-04 10:16:52 +0000194 xwrite(ofd, iobuf, nread);
Rob Landley1cca9482006-07-10 19:45:20 +0000195 if (delay > 0) sleep(delay);
Eric Andersen2ce1edc1999-10-12 15:42:48 +0000196 }
Erik Andersene49d5ec2000-02-08 19:58:47 +0000197 }
198 }
Eric Andersencc8ed391999-10-05 16:24:54 +0000199}
Denis Vlasenko29fe7262007-04-05 20:26:28 +0000200#endif