mtrmt.c revision 1.20 
1/*	$OpenBSD: mtrmt.c,v 1.20 2012/12/04 02:38:51 deraadt Exp $	*/
2/*	$NetBSD: mtrmt.c,v 1.2 1996/03/06 06:22:07 scottr Exp $	*/
3
4/*-
5 * Copyright (c) 1980, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include <sys/types.h>
34#include <sys/mtio.h>
35#include <sys/ioctl.h>
36#include <sys/socket.h>
37#include <sys/time.h>
38#include <ufs/ufs/dinode.h>
39
40#include <netinet/in.h>
41#include <netinet/tcp.h>
42
43#include <protocols/dumprestore.h>
44
45#include <ctype.h>
46#include <err.h>
47#include <netdb.h>
48#include <pwd.h>
49#include <signal.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <string.h>
53#include <unistd.h>
54
55#include "pathnames.h"
56#include "mt.h"
57
58#define	TS_CLOSED	0
59#define	TS_OPEN		1
60
61static	int rmtstate = TS_CLOSED;
62static	int rmtape;
63static	char *rmtpeer;
64
65static	int okname(char *);
66static	int rmtcall(char *, char *);
67static	void rmtconnaborted(void);
68static	void sigrmtconnaborted(int);
69static	int rmtgetb(void);
70static	void rmtgetconn(void);
71static	void rmtgets(char *, int);
72static	int rmtreply(char *);
73
74int
75rmthost(char *host)
76{
77	if ((rmtpeer = strdup(host)) == NULL)
78		err(1, "strdup");
79	signal(SIGPIPE, sigrmtconnaborted);
80	rmtgetconn();
81	if (rmtape < 0)
82		return (0);
83	return (1);
84}
85
86/* ARGSUSED */
87static void
88sigrmtconnaborted(int signo)
89{
90
91	warnx("Lost connection to remote host.");
92	_exit(1);
93}
94
95static void
96rmtconnaborted(void)
97{
98
99	errx(1, "Lost connection to remote host.");
100}
101
102void
103rmtgetconn(void)
104{
105	char *cp;
106	static struct servent *sp = NULL;
107	static struct passwd *pwd = NULL;
108#ifdef notdef
109	static int on = 1;
110#endif
111	char *tuser;
112	int size;
113	int maxseg;
114
115	if (sp == NULL) {
116		sp = getservbyname("shell", "tcp");
117		if (sp == NULL)
118			errx(1, "shell/tcp: unknown service");
119		pwd = getpwuid(getuid());
120		if (pwd == NULL)
121			errx(1, "who are you?");
122	}
123	if ((cp = strchr(rmtpeer, '@')) != NULL) {
124		tuser = rmtpeer;
125		*cp = '\0';
126		if (!okname(tuser))
127			exit(1);
128		rmtpeer = ++cp;
129	} else
130		tuser = pwd->pw_name;
131
132	rmtape = rcmd(&rmtpeer, (u_short)sp->s_port, pwd->pw_name, tuser,
133	    _PATH_RMT, NULL);
134	if (rmtape == -1)
135		exit(1);		/* rcmd already printed error message */
136
137	size = TP_BSIZE;
138	if (size > 60 * 1024)		/* XXX */
139		size = 60 * 1024;
140	/* Leave some space for rmt request/response protocol */
141	size += 2 * 1024;
142
143	while (size > TP_BSIZE &&
144	    setsockopt(rmtape, SOL_SOCKET, SO_SNDBUF, &size, sizeof (size)) < 0)
145		    size -= TP_BSIZE;
146	(void)setsockopt(rmtape, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size));
147
148	maxseg = 1024;
149	(void)setsockopt(rmtape, IPPROTO_TCP, TCP_MAXSEG, &maxseg,
150		sizeof (maxseg));
151
152#ifdef notdef
153	if (setsockopt(rmtape, IPPROTO_TCP, TCP_NODELAY, &on, sizeof (on)) < 0)
154		perror("TCP_NODELAY setsockopt");
155#endif
156}
157
158static int
159okname(char *cp0)
160{
161	char *cp;
162	int c;
163
164	for (cp = cp0; *cp; cp++) {
165		c = *cp;
166		if (!isascii(c) || !(isalnum(c) || c == '_' || c == '-')) {
167			warnx("invalid user name: %s", cp0);
168			return (0);
169		}
170	}
171	return (1);
172}
173
174int
175rmtopen(char *tape, int mode)
176{
177	char buf[256];
178
179	(void)snprintf(buf, sizeof (buf), "O%s\n%d\n", tape, mode);
180	rmtstate = TS_OPEN;
181	return (rmtcall(tape, buf));
182}
183
184void
185rmtclose(void)
186{
187
188	if (rmtstate != TS_OPEN)
189		return;
190	rmtcall("close", "C\n");
191	rmtstate = TS_CLOSED;
192}
193
194struct	mtget mts;
195
196struct mtget *
197rmtstatus(void)
198{
199	int i;
200	char *cp;
201
202	if (rmtstate != TS_OPEN)
203		return (NULL);
204	rmtcall("status", "S\n");
205	for (i = 0, cp = (char *)&mts; i < sizeof(mts); i++)
206		*cp++ = rmtgetb();
207	return (&mts);
208}
209
210int
211rmtioctl(int cmd, int count)
212{
213	char buf[256];
214
215	if (count < 0)
216		return (-1);
217	(void)snprintf(buf, sizeof (buf), "I%d\n%d\n", cmd, count);
218	return (rmtcall("ioctl", buf));
219}
220
221static int
222rmtcall(char *cmd, char *buf)
223{
224
225	if (write(rmtape, buf, strlen(buf)) != strlen(buf))
226		rmtconnaborted();
227	return (rmtreply(cmd));
228}
229
230static int
231rmtreply(char *cmd)
232{
233	char *cp;
234	char code[30], emsg[BUFSIZ];
235
236	rmtgets(code, sizeof (code));
237	if (*code == 'E' || *code == 'F') {
238		rmtgets(emsg, sizeof (emsg));
239		warnx("%s: %s", cmd, emsg);
240		if (*code == 'F') {
241			rmtstate = TS_CLOSED;
242			return (-1);
243		}
244		return (-1);
245	}
246	if (*code != 'A') {
247		/* Kill trailing newline */
248		cp = code + strlen(code);
249		if (cp > code && *--cp == '\n')
250			*cp = '\0';
251
252		warnx("Protocol to remote tape server botched (code \"%s\").",
253		    code);
254		rmtconnaborted();
255	}
256	return (atoi(code + 1));
257}
258
259int
260rmtgetb(void)
261{
262	char c;
263
264	if (read(rmtape, &c, 1) != 1)
265		rmtconnaborted();
266	return (c);
267}
268
269/* Get a line (guaranteed to have a trailing newline). */
270void
271rmtgets(char *line, int len)
272{
273	char *cp = line;
274
275	while (len > 1) {
276		*cp = rmtgetb();
277		if (*cp == '\n') {
278			cp[1] = '\0';
279			return;
280		}
281		cp++;
282		len--;
283	}
284	*cp = '\0';
285	warnx("Protocol to remote tape server botched.");
286	warnx("(rmtgets got \"%s\").", line);
287	rmtconnaborted();
288}
289