xref: /freebsd/usr.sbin/rmt/rmt.c (revision 41059135ce931c0f1014a999ffabc6bc470ce856)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if 0
31 #ifndef lint
32 static const char copyright[] =
33 "@(#) Copyright (c) 1983, 1993\n\
34 	The Regents of the University of California.  All rights reserved.\n";
35 #endif /* not lint */
36 
37 #ifndef lint
38 static char sccsid[] = "@(#)rmt.c	8.1 (Berkeley) 6/6/93";
39 #endif /* not lint */
40 #endif
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 /*
45  * rmt
46  */
47 #include <sys/types.h>
48 #include <sys/socket.h>
49 #include <sys/mtio.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 
57 static int	tape = -1;
58 
59 static char	*record;
60 static int	maxrecsize = -1;
61 
62 #define	SSIZE	64
63 static char	device[SSIZE];
64 static char	count[SSIZE], mode[SSIZE], pos[SSIZE], op[SSIZE];
65 
66 static char	resp[BUFSIZ];
67 
68 static FILE	*debug;
69 #define	DEBUG(f)	if (debug) fprintf(debug, f)
70 #define	DEBUG1(f,a)	if (debug) fprintf(debug, f, a)
71 #define	DEBUG2(f,a1,a2)	if (debug) fprintf(debug, f, a1, a2)
72 
73 static char	*checkbuf(char *, int);
74 static void	 error(int);
75 static void	 getstring(char *);
76 
77 int
78 main(int argc, char **argv)
79 {
80 	int rval;
81 	char c;
82 	int n, i, cc;
83 
84 	argc--, argv++;
85 	if (argc > 0) {
86 		debug = fopen(*argv, "w");
87 		if (debug == NULL) {
88 			DEBUG1("rmtd: error to open %s\n", *argv);
89 			exit(1);
90 		}
91 		(void)setbuf(debug, (char *)0);
92 	}
93 top:
94 	errno = 0;
95 	rval = 0;
96 	if (read(STDIN_FILENO, &c, 1) != 1)
97 		exit(0);
98 	switch (c) {
99 
100 	case 'O':
101 		if (tape >= 0)
102 			(void) close(tape);
103 		getstring(device);
104 		getstring(mode);
105 		DEBUG2("rmtd: O %s %s\n", device, mode);
106 		/*
107 		 * XXX the rmt protocol does not provide a means to
108 		 * specify the permission bits; allow rw for everyone,
109 		 * as modified by the users umask
110 		 */
111 		tape = open(device, atoi(mode), 0666);
112 		if (tape < 0)
113 			goto ioerror;
114 		goto respond;
115 
116 	case 'C':
117 		DEBUG("rmtd: C\n");
118 		getstring(device);		/* discard */
119 		if (close(tape) < 0)
120 			goto ioerror;
121 		tape = -1;
122 		goto respond;
123 
124 	case 'L':
125 		getstring(count);
126 		getstring(pos);
127 		DEBUG2("rmtd: L %s %s\n", count, pos);
128 		rval = lseek(tape, (off_t)strtoll(count, NULL, 10), atoi(pos));
129 		if (rval < 0)
130 			goto ioerror;
131 		goto respond;
132 
133 	case 'W':
134 		getstring(count);
135 		n = atoi(count);
136 		DEBUG1("rmtd: W %s\n", count);
137 		record = checkbuf(record, n);
138 		for (i = 0; i < n; i += cc) {
139 			cc = read(STDIN_FILENO, &record[i], n - i);
140 			if (cc <= 0) {
141 				DEBUG("rmtd: premature eof\n");
142 				exit(2);
143 			}
144 		}
145 		rval = write(tape, record, n);
146 		if (rval < 0)
147 			goto ioerror;
148 		goto respond;
149 
150 	case 'R':
151 		getstring(count);
152 		DEBUG1("rmtd: R %s\n", count);
153 		n = atoi(count);
154 		record = checkbuf(record, n);
155 		rval = read(tape, record, n);
156 		if (rval < 0)
157 			goto ioerror;
158 		(void)sprintf(resp, "A%d\n", rval);
159 		(void)write(STDOUT_FILENO, resp, strlen(resp));
160 		(void)write(STDOUT_FILENO, record, rval);
161 		goto top;
162 
163 	case 'I':
164 		getstring(op);
165 		getstring(count);
166 		DEBUG2("rmtd: I %s %s\n", op, count);
167 		{ struct mtop mtop;
168 		  mtop.mt_op = atoi(op);
169 		  mtop.mt_count = atoi(count);
170 		  if (ioctl(tape, MTIOCTOP, (char *)&mtop) < 0)
171 			goto ioerror;
172 		  rval = mtop.mt_count;
173 		}
174 		goto respond;
175 
176 	case 'S':		/* status */
177 		DEBUG("rmtd: S\n");
178 		{ struct mtget mtget;
179 		  if (ioctl(tape, MTIOCGET, (char *)&mtget) < 0)
180 			goto ioerror;
181 		  rval = sizeof (mtget);
182 		  if (rval > 24)	/* original mtget structure size */
183 			rval = 24;
184 		  (void)sprintf(resp, "A%d\n", rval);
185 		  (void)write(STDOUT_FILENO, resp, strlen(resp));
186 		  (void)write(STDOUT_FILENO, (char *)&mtget, rval);
187 		  goto top;
188 		}
189 
190         case 'V':               /* version */
191                 getstring(op);
192                 DEBUG1("rmtd: V %s\n", op);
193                 rval = 2;
194                 goto respond;
195 
196 	default:
197 		DEBUG1("rmtd: garbage command %c\n", c);
198 		exit(3);
199 	}
200 respond:
201 	DEBUG1("rmtd: A %d\n", rval);
202 	(void)sprintf(resp, "A%d\n", rval);
203 	(void)write(STDOUT_FILENO, resp, strlen(resp));
204 	goto top;
205 ioerror:
206 	error(errno);
207 	goto top;
208 }
209 
210 void
211 getstring(char *bp)
212 {
213 	int i;
214 	char *cp = bp;
215 
216 	for (i = 0; i < SSIZE; i++) {
217 		if (read(STDIN_FILENO, cp+i, 1) != 1)
218 			exit(0);
219 		if (cp[i] == '\n')
220 			break;
221 	}
222 	cp[i] = '\0';
223 }
224 
225 static char *
226 checkbuf(char *rec, int size)
227 {
228 
229 	if (size <= maxrecsize)
230 		return (rec);
231 	if (rec != NULL)
232 		free(rec);
233 	rec = malloc(size);
234 	if (rec == NULL) {
235 		DEBUG("rmtd: cannot allocate buffer space\n");
236 		exit(4);
237 	}
238 	maxrecsize = size;
239 	while (size > 1024 &&
240 	       setsockopt(0, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size)) < 0)
241 		size -= 1024;
242 	return (rec);
243 }
244 
245 static void
246 error(int num)
247 {
248 
249 	DEBUG2("rmtd: E %d (%s)\n", num, strerror(num));
250 	(void)snprintf(resp, sizeof(resp), "E%d\n%s\n", num, strerror(num));
251 	(void)write(STDOUT_FILENO, resp, strlen(resp));
252 }
253