xref: /freebsd/usr.sbin/rmt/rmt.c (revision 3706af423ff257540dfe88bcb91fb0ab54e60946)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if 0
33 #ifndef lint
34 static const char copyright[] =
35 "@(#) Copyright (c) 1983, 1993\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif /* not lint */
38 
39 #ifndef lint
40 static char sccsid[] = "@(#)rmt.c	8.1 (Berkeley) 6/6/93";
41 #endif /* not lint */
42 #endif
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 /*
47  * rmt
48  */
49 #include <sys/types.h>
50 #include <sys/socket.h>
51 #include <sys/mtio.h>
52 #include <errno.h>
53 #include <fcntl.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58 
59 static int	tape = -1;
60 
61 static char	*record;
62 static int	maxrecsize = -1;
63 
64 #define	SSIZE	64
65 static char	device[SSIZE];
66 static char	count[SSIZE], mode[SSIZE], pos[SSIZE], op[SSIZE];
67 
68 static char	resp[BUFSIZ];
69 
70 static FILE	*debug;
71 #define	DEBUG(f)	if (debug) fprintf(debug, f)
72 #define	DEBUG1(f,a)	if (debug) fprintf(debug, f, a)
73 #define	DEBUG2(f,a1,a2)	if (debug) fprintf(debug, f, a1, a2)
74 
75 static char	*checkbuf(char *, int);
76 static void	 error(int);
77 static void	 getstring(char *);
78 
79 int
80 main(int argc, char **argv)
81 {
82 	int rval;
83 	char c;
84 	int n, i, cc;
85 
86 	argc--, argv++;
87 	if (argc > 0) {
88 		debug = fopen(*argv, "w");
89 		if (debug == NULL) {
90 			DEBUG1("rmtd: error to open %s\n", *argv);
91 			exit(1);
92 		}
93 		(void)setbuf(debug, (char *)0);
94 	}
95 top:
96 	errno = 0;
97 	rval = 0;
98 	if (read(STDIN_FILENO, &c, 1) != 1)
99 		exit(0);
100 	switch (c) {
101 
102 	case 'O':
103 		if (tape >= 0)
104 			(void) close(tape);
105 		getstring(device);
106 		getstring(mode);
107 		DEBUG2("rmtd: O %s %s\n", device, mode);
108 		/*
109 		 * XXX the rmt protocol does not provide a means to
110 		 * specify the permission bits; allow rw for everyone,
111 		 * as modified by the users umask
112 		 */
113 		tape = open(device, atoi(mode), 0666);
114 		if (tape < 0)
115 			goto ioerror;
116 		goto respond;
117 
118 	case 'C':
119 		DEBUG("rmtd: C\n");
120 		getstring(device);		/* discard */
121 		if (close(tape) < 0)
122 			goto ioerror;
123 		tape = -1;
124 		goto respond;
125 
126 	case 'L':
127 		getstring(count);
128 		getstring(pos);
129 		DEBUG2("rmtd: L %s %s\n", count, pos);
130 		rval = lseek(tape, (off_t)strtoll(count, NULL, 10), atoi(pos));
131 		if (rval < 0)
132 			goto ioerror;
133 		goto respond;
134 
135 	case 'W':
136 		getstring(count);
137 		n = atoi(count);
138 		DEBUG1("rmtd: W %s\n", count);
139 		record = checkbuf(record, n);
140 		for (i = 0; i < n; i += cc) {
141 			cc = read(STDIN_FILENO, &record[i], n - i);
142 			if (cc <= 0) {
143 				DEBUG("rmtd: premature eof\n");
144 				exit(2);
145 			}
146 		}
147 		rval = write(tape, record, n);
148 		if (rval < 0)
149 			goto ioerror;
150 		goto respond;
151 
152 	case 'R':
153 		getstring(count);
154 		DEBUG1("rmtd: R %s\n", count);
155 		n = atoi(count);
156 		record = checkbuf(record, n);
157 		rval = read(tape, record, n);
158 		if (rval < 0)
159 			goto ioerror;
160 		(void)sprintf(resp, "A%d\n", rval);
161 		(void)write(STDOUT_FILENO, resp, strlen(resp));
162 		(void)write(STDOUT_FILENO, record, rval);
163 		goto top;
164 
165 	case 'I':
166 		getstring(op);
167 		getstring(count);
168 		DEBUG2("rmtd: I %s %s\n", op, count);
169 		{ struct mtop mtop;
170 		  mtop.mt_op = atoi(op);
171 		  mtop.mt_count = atoi(count);
172 		  if (ioctl(tape, MTIOCTOP, (char *)&mtop) < 0)
173 			goto ioerror;
174 		  rval = mtop.mt_count;
175 		}
176 		goto respond;
177 
178 	case 'S':		/* status */
179 		DEBUG("rmtd: S\n");
180 		{ struct mtget mtget;
181 		  if (ioctl(tape, MTIOCGET, (char *)&mtget) < 0)
182 			goto ioerror;
183 		  rval = sizeof (mtget);
184 		  if (rval > 24)	/* original mtget structure size */
185 			rval = 24;
186 		  (void)sprintf(resp, "A%d\n", rval);
187 		  (void)write(STDOUT_FILENO, resp, strlen(resp));
188 		  (void)write(STDOUT_FILENO, (char *)&mtget, rval);
189 		  goto top;
190 		}
191 
192         case 'V':               /* version */
193                 getstring(op);
194                 DEBUG1("rmtd: V %s\n", op);
195                 rval = 2;
196                 goto respond;
197 
198 	default:
199 		DEBUG1("rmtd: garbage command %c\n", c);
200 		exit(3);
201 	}
202 respond:
203 	DEBUG1("rmtd: A %d\n", rval);
204 	(void)sprintf(resp, "A%d\n", rval);
205 	(void)write(STDOUT_FILENO, resp, strlen(resp));
206 	goto top;
207 ioerror:
208 	error(errno);
209 	goto top;
210 }
211 
212 void
213 getstring(char *bp)
214 {
215 	int i;
216 	char *cp = bp;
217 
218 	for (i = 0; i < SSIZE; i++) {
219 		if (read(STDIN_FILENO, cp+i, 1) != 1)
220 			exit(0);
221 		if (cp[i] == '\n')
222 			break;
223 	}
224 	cp[i] = '\0';
225 }
226 
227 static char *
228 checkbuf(char *rec, int size)
229 {
230 
231 	if (size <= maxrecsize)
232 		return (rec);
233 	if (rec != NULL)
234 		free(rec);
235 	rec = malloc(size);
236 	if (rec == NULL) {
237 		DEBUG("rmtd: cannot allocate buffer space\n");
238 		exit(4);
239 	}
240 	maxrecsize = size;
241 	while (size > 1024 &&
242 	       setsockopt(0, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size)) < 0)
243 		size -= 1024;
244 	return (rec);
245 }
246 
247 static void
248 error(int num)
249 {
250 
251 	DEBUG2("rmtd: E %d (%s)\n", num, strerror(num));
252 	(void)snprintf(resp, sizeof(resp), "E%d\n%s\n", num, strerror(num));
253 	(void)write(STDOUT_FILENO, resp, strlen(resp));
254 }
255