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