term.c revision 105:5440d7a4f376 
1/* $Id$ */
2/* $OpenBSD: netcat.c,v 1.57 2002/12/30 18:00:18 stevesk Exp $ */
3/*
4 * Copyright (c) 2001 Eric Jackson <ericj@monkey.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *   notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *   notice, this list of conditions and the following disclaimer in the
14 *   documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 *   derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <sys/types.h>
31#include <sys/socket.h>
32#include <sys/termios.h>
33#include <sys/time.h>
34#include <sys/un.h>
35
36#include <netinet/in.h>
37#include <arpa/telnet.h>
38
39#include <err.h>
40#include <errno.h>
41#include <netdb.h>
42#include <poll.h>
43#include <stdarg.h>
44#include <stdio.h>
45#include <stdlib.h>
46#include <string.h>
47#include <unistd.h>
48#include <fcntl.h>
49
50ssize_t	atomicio(ssize_t (*)(), int, void *, size_t);
51void	readwrite(int);
52int	remote_connect(char *, char *, struct addrinfo);
53
54struct	termios saved_ios;
55void	raw_term();
56void	restore_term();
57
58char	progname[256];
59void	usage(int);
60
61int
62main(int argc, char *argv[])
63{
64        int ch, s, ret;
65        char *host, *port, *endp;
66        struct addrinfo hints;
67        socklen_t len;
68
69        ret = 1;
70        s = 0;
71        host = NULL;
72        port = NULL;
73        endp = NULL;
74
75        strncpy(progname, argv[0], sizeof progname);
76
77        /* Cruft to make sure options are clean, and used properly. */
78        if (argc != 3 || !argv[1] || !argv[2])
79                usage(1);
80
81        host = argv[1];
82        port = argv[2];
83
84
85        if (!isatty(STDIN_FILENO))
86                errx(1, "not attached to a terminal");
87
88        raw_term();
89
90        /* Initialize addrinfo structure */
91        memset(&hints, 0, sizeof(struct addrinfo));
92        hints.ai_family = AF_UNSPEC;
93        hints.ai_socktype = SOCK_STREAM;
94        hints.ai_protocol = IPPROTO_TCP;
95
96        s = remote_connect(host, port, hints);
97        ret = 0;
98        readwrite(s);
99
100        if (s)
101                close(s);
102
103        exit(ret);
104}
105
106/*
107 * remote_connect()
108 * Return's a socket connected to a remote host. Properly bind's to a local
109 * port or source address if needed. Return's -1 on failure.
110 */
111int
112remote_connect(char *host, char *port, struct addrinfo hints)
113{
114        struct addrinfo *res, *res0;
115        int s, error;
116
117        if ((error = getaddrinfo(host, port, &hints, &res)))
118                errx(1, "getaddrinfo: %s", gai_strerror(error));
119
120        res0 = res;
121        do {
122                if ((s = socket(res0->ai_family, res0->ai_socktype,
123                    res0->ai_protocol)) < 0)
124                        continue;
125
126                if (connect(s, res0->ai_addr, res0->ai_addrlen) == 0)
127                        break;
128
129                close(s);
130                s = -1;
131        } while ((res0 = res0->ai_next) != NULL);
132
133        freeaddrinfo(res);
134
135        return (s);
136}
137
138/*
139 * readwrite()
140 * Loop that polls on the network file descriptor and stdin.
141 */
142void
143readwrite(int nfd)
144{
145        struct pollfd pfd[2];
146        char buf[BUFSIZ];
147        int wfd = fileno(stdin), n, ret;
148        int lfd = fileno(stdout);
149        int escape = 0;
150
151        /* Setup Network FD */
152        pfd[0].fd = nfd;
153        pfd[0].events = POLLIN;
154
155        /* Setup STDIN FD */
156        pfd[1].fd = wfd;
157        pfd[1].events = POLLIN;
158
159        while (pfd[0].fd != -1) {
160                if ((n = poll(pfd, 2, -1)) < 0) {
161                        close(nfd);
162                        err(1, "Polling Error");
163                }
164
165                if (n == 0)
166                        return;
167
168                if (pfd[0].revents & POLLIN) {
169                        if ((n = read(nfd, buf, sizeof(buf))) < 0)
170                                return;
171                        else if (n == 0) {
172                                shutdown(nfd, SHUT_RD);
173                                pfd[0].fd = -1;
174                                pfd[0].events = 0;
175                        } else {
176                                if ((ret = atomicio(write, lfd, buf, n)) != n)
177                                        return;
178                        }
179                }
180
181                if (pfd[1].revents & POLLIN) {
182                        if ((n = read(wfd, buf, sizeof(buf))) < 0)
183                                return;
184                        else if (n == 0) {
185                                shutdown(nfd, SHUT_WR);
186                                pfd[1].fd = -1;
187                                pfd[1].events = 0;
188                        } else {
189                                if (escape) {
190                                        char buf2[] = "~";
191                                        if (*buf == '.') {
192                                                printf("quit!\n");
193                                                return;
194                                        }
195                                        escape = 0;
196                                        if (*buf != '~' &&
197                                            (ret = atomicio(write, nfd, buf2, 1)) != n)
198                                                return;
199                                } else {
200                                        escape = (*buf == '~');
201                                        if (escape)
202                                                continue;
203                                }
204
205                                if ((ret = atomicio(write, nfd, buf, n)) != n)
206                                        return;
207                        }
208                }
209        }
210}
211
212void
213usage(int ret)
214{
215        fprintf(stderr, "usage: %s hostname port\n", progname);
216        if (ret)
217                exit(1);
218}
219
220/*
221 * Copyright (c) 1995,1999 Theo de Raadt.  All rights reserved.
222 * All rights reserved.
223 *
224 * Redistribution and use in source and binary forms, with or without
225 * modification, are permitted provided that the following conditions
226 * are met:
227 * 1. Redistributions of source code must retain the above copyright
228 *    notice, this list of conditions and the following disclaimer.
229 * 2. Redistributions in binary form must reproduce the above copyright
230 *    notice, this list of conditions and the following disclaimer in the
231 *    documentation and/or other materials provided with the distribution.
232 *
233 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
234 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
235 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
236 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
237 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
238 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
239 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
240 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
241 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
242 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
243 */
244
245/*
246 * ensure all of data on socket comes through. f==read || f==write
247 */
248ssize_t
249atomicio(ssize_t (*f) (), int fd, void *_s, size_t n)
250{
251        char *s = _s;
252        ssize_t res, pos = 0;
253
254        while (n > pos) {
255                res = (f) (fd, s + pos, n - pos);
256                switch (res) {
257                case -1:
258                        if (errno == EINTR || errno == EAGAIN)
259                                continue;
260                case 0:
261                        return (res);
262                default:
263                        pos += res;
264                }
265        }
266        return (pos);
267}
268
269/*
270 * Copyright (c) 2003 Nathan L. Binkert <binkertn@umich.edu>
271 *
272 * Permission to use, copy, modify, and distribute this software for any
273 * purpose with or without fee is hereby granted, provided that the above
274 * copyright notice and this permission notice appear in all copies.
275 *
276 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
277 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
278 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
279 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
280 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
281 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
282 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
283 */
284
285void
286raw_term()
287{
288        struct termios ios;
289
290        if (tcgetattr(STDIN_FILENO, &ios) < 0)
291            errx(1, "tcgetagttr\n");
292
293        memcpy(&saved_ios, &ios, sizeof(struct termios));
294
295        ios.c_iflag &= ~(ISTRIP|ICRNL|IGNCR|ICRNL|IXOFF|IXON);
296        ios.c_oflag &= ~(OPOST);
297        ios.c_oflag &= (ONLCR);
298        ios.c_lflag &= ~(ISIG|ICANON|ECHO);
299        ios.c_cc[VMIN] = 1;
300        ios.c_cc[VTIME] = 0;
301
302        if (tcsetattr(STDIN_FILENO, TCSANOW, &ios) < 0)
303            errx(1, "tcsetattr\n");
304
305        atexit(restore_term);
306}
307
308void
309restore_term()
310{
311        tcsetattr(STDIN_FILENO, TCSANOW, &saved_ios);
312}
313