xref: /netbsd-src/sbin/mbrlabel/mbrlabel.c (revision 20bad51bebdabf097abdafeb2ad247ded5441109)
1 /*	$NetBSD: mbrlabel.c,v 1.29 2018/03/30 13:14:25 mlelstv Exp $	*/
2 
3 /*
4  * Copyright (C) 1998 Wolfgang Solfrank.
5  * Copyright (C) 1998 TooLs GmbH.
6  * 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. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by TooLs GmbH.
19  * 4. The name of TooLs GmbH may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
28  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #ifndef lint
36 __RCSID("$NetBSD: mbrlabel.c,v 1.29 2018/03/30 13:14:25 mlelstv Exp $");
37 #endif /* not lint */
38 
39 #include <stdio.h>
40 #include <err.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <limits.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47 #include <util.h>
48 
49 #include <sys/param.h>
50 #define FSTYPENAMES
51 #include <sys/disklabel.h>
52 #include <sys/bootblock.h>
53 #include <sys/ioctl.h>
54 
55 #include "dkcksum.h"
56 #include "extern.h"
57 
58 __dead static void	usage(void);
59 static void	getlabel(int);
60 static void	setlabel(int, int);
61 static int	getparts(int, u_int32_t, u_int32_t, int);
62 static u_int16_t	getshort(void *);
63 static u_int32_t	getlong(void *);
64 
65 struct disklabel label;
66 
67 static void
getlabel(int sd)68 getlabel(int sd)
69 {
70 
71 	if (ioctl(sd, DIOCGDINFO, &label) < 0) {
72 		perror("get label");
73 		exit(1);
74 	}
75 	/*
76 	 * Some ports seem to not set the number of partitions
77 	 * correctly, albeit they seem to set the raw partition ok!
78 	 */
79 	if (label.d_npartitions <= getrawpartition())
80 		label.d_npartitions = getrawpartition() + 1;
81 }
82 
83 static void
setlabel(int sd,int doraw)84 setlabel(int sd, int doraw)
85 {
86 	int one = 1;
87 
88 	label.d_checksum = 0;
89 	label.d_checksum = dkcksum(&label);
90 	if (ioctl(sd, doraw ? DIOCWDINFO : DIOCSDINFO, &label) < 0) {
91 		perror("set label");
92 		exit(1);
93 	}
94 	if (!doraw)
95 		/* If we haven't written to the disk, don't discard on close */
96 		ioctl(sd, DIOCKLABEL, &one);
97 
98 }
99 
100 static u_int16_t
getshort(void * p)101 getshort(void *p)
102 {
103 	unsigned char *cp = p;
104 
105 	return (cp[0] | (cp[1] << 8));
106 }
107 
108 static u_int32_t
getlong(void * p)109 getlong(void *p)
110 {
111 	unsigned char *cp = p;
112 
113 	return (cp[0] | (cp[1] << 8) | (cp[2] << 16) | (cp[3] << 24));
114 }
115 
116 static int
getparts(int sd,u_int32_t off,u_int32_t extoff,int verbose)117 getparts(int sd, u_int32_t off, u_int32_t extoff, int verbose)
118 {
119 	unsigned char		*buf;
120 	struct mbr_partition	parts[MBR_PART_COUNT];
121 	struct partition	npe;
122 	off_t			loff;
123 	int			i, j, unused, changed;
124 	unsigned		bsize = label.d_secsize;
125 
126 	if (bsize < DEV_BSIZE) {
127 		fprintf(stderr,"Invalid sector size %u\n", bsize);
128 		exit(1);
129 	}
130 
131 	buf = malloc(bsize);
132 	if (buf == NULL) {
133 		perror("malloc I/O buffer");
134 		exit(1);
135 	}
136 
137 	changed = 0;
138 	loff = (off_t)off * bsize;
139 
140 	if (lseek(sd, loff, SEEK_SET) != loff) {
141 		perror("seek label");
142 		exit(1);
143 	}
144 	if (read(sd, buf, bsize) != (ssize_t)bsize) {
145 		if (off != MBR_BBSECTOR)
146 			perror("read label (sector is possibly out of "
147 			    "range)");
148 		else
149 			perror("read label");
150 		exit(1);
151 	}
152 	if (getshort(buf + MBR_MAGIC_OFFSET) != MBR_MAGIC)
153 		return (changed);
154 	memcpy(parts, buf + MBR_PART_OFFSET, sizeof parts);
155 
156 				/* scan partition table */
157 	for (i = 0; i < MBR_PART_COUNT; i++) {
158 		if (parts[i].mbrp_type == 0 ||
159 				/* extended partitions are handled below */
160 		    MBR_IS_EXTENDED(parts[i].mbrp_type))
161 			continue;
162 
163 		memset((void *)&npe, 0, sizeof(npe));
164 		npe.p_size = getlong(&parts[i].mbrp_size);
165 		npe.p_offset = getlong(&parts[i].mbrp_start) + off;
166 		npe.p_fstype = xlat_mbr_fstype(parts[i].mbrp_type);
167 
168 				/* find existing entry, or first free slot */
169 		unused = -1;	/* flag as no free slot */
170 		if (verbose)
171 			printf(
172 			    "Found %s partition; size %u (%u MB), offset %u\n",
173 			    fstypenames[npe.p_fstype],
174 			    npe.p_size, npe.p_size / 2048, npe.p_offset);
175 
176 		for (j = 0; j < label.d_npartitions; j++) {
177 			struct partition *lpe;
178 
179 			if (j == RAW_PART)
180 				continue;
181 			lpe = &label.d_partitions[j];
182 
183 			if (lpe->p_size == npe.p_size &&
184 			    lpe->p_offset == npe.p_offset) {
185 				if (verbose)
186 					printf(
187 					    "  skipping existing %s partition at slot %c.\n",
188 					    fstypenames[lpe->p_fstype],
189 					    j + 'a');
190 				unused = -2;	/* flag as existing */
191 				break;
192 			}
193 
194 			if (unused == -1 && lpe->p_size == 0 &&
195 			    lpe->p_fstype == FS_UNUSED)
196 				unused = j;
197 		}
198 		if (unused == -1) {
199 			for (j = 0; j < label.d_npartitions; j++) {
200 				struct partition *lpe;
201 
202 				if (j == RAW_PART)
203 					continue;
204 				lpe = &label.d_partitions[j];
205 
206 				if ((npe.p_offset >= lpe->p_offset &&
207 				    npe.p_offset < lpe->p_offset + lpe->p_size) ||
208 				   (npe.p_offset + npe.p_size - 1 >= lpe->p_offset &&
209 				    npe.p_offset + npe.p_size - 1 < lpe->p_offset + lpe->p_size)) {
210 					printf(
211 					    "  skipping overlapping %s partition at slot %c.\n",
212 					    fstypenames[lpe->p_fstype],
213 					    j + 'a');
214 					unused = -2;	/* flag as existing */
215 					break;
216 				}
217 			}
218 		}
219 		if (unused == -2)
220 			continue;	/* entry exists, skip... */
221 		if (unused == -1) {
222 			if (label.d_npartitions < MAXPARTITIONS) {
223 				unused = label.d_npartitions;
224 				label.d_npartitions++;
225 			} else {
226 				printf(
227 				"  WARNING: no slots free for %s partition.\n",
228 				    fstypenames[npe.p_fstype]);
229 				continue;
230 			}
231 		}
232 
233 		if (verbose)
234 			printf("  adding %s partition to slot %c.\n",
235 			    fstypenames[npe.p_fstype], unused + 'a');
236 
237 		/*
238 		 * XXX guess some filesystem parameters, these should be
239 		 * scanned from the superblocks
240 		 */
241 		switch (npe.p_fstype) {
242 		case FS_BSDFFS:
243 		case FS_APPLEUFS:
244 			npe.p_fsize = 1024;
245 			npe.p_frag = 8;
246 			npe.p_cpg = 16;
247 			break;
248 		case FS_BSDLFS:
249 			npe.p_fsize = 1024;
250 			npe.p_frag = 8;
251 			npe.p_sgs = 7;
252 			break;
253 		}
254 
255 		changed++;
256 		label.d_partitions[unused] = npe;
257 	}
258 
259 				/* recursively scan extended partitions */
260 	for (i = 0; i < MBR_PART_COUNT; i++) {
261 		u_int32_t poff;
262 
263 		if (MBR_IS_EXTENDED(parts[i].mbrp_type)) {
264 			poff = getlong(&parts[i].mbrp_start) + extoff;
265 			changed += getparts(sd, poff,
266 			    extoff ? extoff : poff, verbose);
267 		}
268 	}
269 
270 	free(buf);
271 	return (changed);
272 }
273 
274 static void
usage(void)275 usage(void)
276 {
277 	fprintf(stderr, "usage: %s [-fqrw] [-s sector] device\n",
278 	    getprogname());
279 	exit(1);
280 }
281 
282 
283 int
main(int argc,char ** argv)284 main(int argc, char **argv)
285 {
286 	int	sd, ch, changed;
287 	char	*ep, name[MAXPATHLEN];
288 	int	force;			/* force label update */
289 	int	raw;			/* update on-disk label as well */
290 	int	verbose;		/* verbose output */
291 	int	write_it;		/* update in-core label if changed */
292 	uint32_t sector;		/* sector that contains the MBR */
293 	ulong	ulsector;
294 
295 	force = 0;
296 	raw = 0;
297 	verbose = 1;
298 	write_it = 0;
299 	sector = MBR_BBSECTOR;
300 	while ((ch = getopt(argc, argv, "fqrs:w")) != -1) {
301 		switch (ch) {
302 		case 'f':
303 			force = 1;
304 			break;
305 		case 'q':
306 			verbose = 0;
307 			break;
308 		case 'r':
309 			raw = 1;
310 			break;
311 		case 's':
312 			errno = 0;
313 			ulsector = strtoul(optarg, &ep, 10);
314 			if (optarg[0] == '\0' || *ep != '\0')
315 				errx(EXIT_FAILURE,
316 				    "sector number (%s) incorrectly specified",
317 				    optarg);
318 			if ((errno == ERANGE && ulsector == ULONG_MAX) ||
319 			    ulsector > UINT32_MAX)
320 			    	errx(EXIT_FAILURE,
321 				    "sector number (%s) out of range",
322 				    optarg);
323 			sector = (uint32_t)ulsector;
324 			break;
325 		case 'w':
326 			write_it = 1;
327 			break;
328 		default:
329 			usage();
330 		}
331 	}
332 	argc -= optind;
333 	argv += optind;
334 	if (argc != 1)
335 		usage();
336 
337 	if ((sd = opendisk(argv[0], write_it ? O_RDWR : O_RDONLY, name,
338 	    (size_t)MAXPATHLEN, 0)) < 0) {
339 		perror(argv[0]);
340 		exit(1);
341 	}
342 	getlabel(sd);
343 	changed = getparts(sd, sector, 0, verbose);
344 
345 	if (verbose) {
346 		putchar('\n');
347 		showpartitions(stdout, &label, 0);
348 		putchar('\n');
349 	}
350 	if (write_it) {
351 		if (! changed && ! force)
352 			printf("No change; not updating disk label.\n");
353 		else {
354 			if (verbose)
355 				printf("Updating in-core %sdisk label.\n",
356 				    raw ? "and on-disk " : "");
357 			setlabel(sd, raw);
358 		}
359 	} else {
360 		printf("Not updating disk label.\n");
361 	}
362 	close(sd);
363 	return (0);
364 }
365