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mbrlabel.c revision 1.28
      1 /*	$NetBSD: mbrlabel.c,v 1.28 2012/07/14 20:14:17 wiz 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 1.28 2012/07/14 20:14:17 wiz 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
     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
     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
    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
    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
    117 getparts(int sd, u_int32_t off, u_int32_t extoff, int verbose)
    118 {
    119 	unsigned char		buf[DEV_BSIZE];
    120 	struct mbr_partition	parts[MBR_PART_COUNT];
    121 	struct partition	npe;
    122 	off_t			loff;
    123 	int			i, j, unused, changed;
    124 
    125 	changed = 0;
    126 	loff = (off_t)off * DEV_BSIZE;
    127 
    128 	if (lseek(sd, loff, SEEK_SET) != loff) {
    129 		perror("seek label");
    130 		exit(1);
    131 	}
    132 	if (read(sd, buf, sizeof buf) != DEV_BSIZE) {
    133 		if (off != MBR_BBSECTOR)
    134 			perror("read label (sector is possibly out of "
    135 			    "range)");
    136 		else
    137 			perror("read label");
    138 		exit(1);
    139 	}
    140 	if (getshort(buf + MBR_MAGIC_OFFSET) != MBR_MAGIC)
    141 		return (changed);
    142 	memcpy(parts, buf + MBR_PART_OFFSET, sizeof parts);
    143 
    144 				/* scan partition table */
    145 	for (i = 0; i < MBR_PART_COUNT; i++) {
    146 		if (parts[i].mbrp_type == 0 ||
    147 				/* extended partitions are handled below */
    148 		    MBR_IS_EXTENDED(parts[i].mbrp_type))
    149 			continue;
    150 
    151 		memset((void *)&npe, 0, sizeof(npe));
    152 		npe.p_size = getlong(&parts[i].mbrp_size);
    153 		npe.p_offset = getlong(&parts[i].mbrp_start) + off;
    154 		npe.p_fstype = xlat_mbr_fstype(parts[i].mbrp_type);
    155 
    156 				/* find existing entry, or first free slot */
    157 		unused = -1;	/* flag as no free slot */
    158 		if (verbose)
    159 			printf(
    160 			    "Found %s partition; size %u (%u MB), offset %u\n",
    161 			    fstypenames[npe.p_fstype],
    162 			    npe.p_size, npe.p_size / 2048, npe.p_offset);
    163 		for (j = 0; j < label.d_npartitions; j++) {
    164 			struct partition *lpe;
    165 
    166 			if (j == RAW_PART)
    167 				continue;
    168 			lpe = &label.d_partitions[j];
    169 			if (lpe->p_size == npe.p_size &&
    170 			    lpe->p_offset == npe.p_offset
    171 #ifdef notyet
    172 			    && (lpe->p_fstype == npe.p_fstype ||
    173 			     lpe->p_fstype == FS_UNUSED) */
    174 #endif
    175 			     ) {
    176 				if (verbose)
    177 					printf(
    178 			    "  skipping existing %s partition at slot %c.\n",
    179 					    fstypenames[lpe->p_fstype],
    180 					    j + 'a');
    181 				unused = -2;	/* flag as existing */
    182 				break;
    183 			}
    184 			if (unused == -1 && lpe->p_size == 0 &&
    185 			    lpe->p_fstype == FS_UNUSED)
    186 				unused = j;
    187 		}
    188 		if (unused == -2)
    189 			continue;	/* entry exists, skip... */
    190 		if (unused == -1) {
    191 			if (label.d_npartitions < MAXPARTITIONS) {
    192 				unused = label.d_npartitions;
    193 				label.d_npartitions++;
    194 			} else {
    195 				printf(
    196 				"  WARNING: no slots free for %s partition.\n",
    197 				    fstypenames[npe.p_fstype]);
    198 				continue;
    199 			}
    200 		}
    201 
    202 		if (verbose)
    203 			printf("  adding %s partition to slot %c.\n",
    204 			    fstypenames[npe.p_fstype], unused + 'a');
    205 		switch (npe.p_fstype) {
    206 		case FS_BSDFFS:
    207 		case FS_APPLEUFS:
    208 			npe.p_size = 16384;	/* XXX */
    209 			npe.p_fsize = 1024;
    210 			npe.p_frag = 8;
    211 			npe.p_cpg = 16;
    212 			break;
    213 #ifdef	__does_not_happen__
    214 		case FS_BSDLFS:
    215 			npe.p_size = 16384;	/* XXX */
    216 			npe.p_fsize = 1024;
    217 			npe.p_frag = 8;
    218 			npe.p_sgs = XXX;
    219 			break;
    220 #endif
    221 		}
    222 		changed++;
    223 		label.d_partitions[unused] = npe;
    224 	}
    225 
    226 				/* recursively scan extended partitions */
    227 	for (i = 0; i < MBR_PART_COUNT; i++) {
    228 		u_int32_t poff;
    229 
    230 		if (MBR_IS_EXTENDED(parts[i].mbrp_type)) {
    231 			poff = getlong(&parts[i].mbrp_start) + extoff;
    232 			changed += getparts(sd, poff,
    233 			    extoff ? extoff : poff, verbose);
    234 		}
    235 	}
    236 	return (changed);
    237 }
    238 
    239 static void
    240 usage(void)
    241 {
    242 	fprintf(stderr, "usage: %s [-fqrw] [-s sector] device\n",
    243 	    getprogname());
    244 	exit(1);
    245 }
    246 
    247 
    248 int
    249 main(int argc, char **argv)
    250 {
    251 	int	sd, ch, changed;
    252 	char	*ep, name[MAXPATHLEN];
    253 	int	force;			/* force label update */
    254 	int	raw;			/* update on-disk label as well */
    255 	int	verbose;		/* verbose output */
    256 	int	write_it;		/* update in-core label if changed */
    257 	uint32_t sector;		/* sector that contains the MBR */
    258 	ulong	ulsector;
    259 
    260 	force = 0;
    261 	raw = 0;
    262 	verbose = 1;
    263 	write_it = 0;
    264 	sector = MBR_BBSECTOR;
    265 	while ((ch = getopt(argc, argv, "fqrs:w")) != -1) {
    266 		switch (ch) {
    267 		case 'f':
    268 			force = 1;
    269 			break;
    270 		case 'q':
    271 			verbose = 0;
    272 			break;
    273 		case 'r':
    274 			raw = 1;
    275 			break;
    276 		case 's':
    277 			errno = 0;
    278 			ulsector = strtoul(optarg, &ep, 10);
    279 			if (optarg[0] == '\0' || *ep != '\0')
    280 				errx(EXIT_FAILURE,
    281 				    "sector number (%s) incorrectly specified",
    282 				    optarg);
    283 			if ((errno == ERANGE && ulsector == ULONG_MAX) ||
    284 			    ulsector > UINT32_MAX)
    285 			    	errx(EXIT_FAILURE,
    286 				    "sector number (%s) out of range",
    287 				    optarg);
    288 			sector = (uint32_t)ulsector;
    289 			break;
    290 		case 'w':
    291 			write_it = 1;
    292 			break;
    293 		default:
    294 			usage();
    295 		}
    296 	}
    297 	argc -= optind;
    298 	argv += optind;
    299 	if (argc != 1)
    300 		usage();
    301 
    302 	if ((sd = opendisk(argv[0], write_it ? O_RDWR : O_RDONLY, name,
    303 	    (size_t)MAXPATHLEN, 0)) < 0) {
    304 		perror(argv[0]);
    305 		exit(1);
    306 	}
    307 	getlabel(sd);
    308 	changed = getparts(sd, sector, 0, verbose);
    309 
    310 	if (verbose) {
    311 		putchar('\n');
    312 		showpartitions(stdout, &label, 0);
    313 		putchar('\n');
    314 	}
    315 	if (write_it) {
    316 		if (! changed && ! force)
    317 			printf("No change; not updating disk label.\n");
    318 		else {
    319 			if (verbose)
    320 				printf("Updating in-core %sdisk label.\n",
    321 				    raw ? "and on-disk " : "");
    322 			setlabel(sd, raw);
    323 		}
    324 	} else {
    325 		printf("Not updating disk label.\n");
    326 	}
    327 	close(sd);
    328 	return (0);
    329 }
    330