2 * Copyright (c) 2008 Luigi Rizzo
3 * Copyright (c) 1999 Robert Nordier
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
19 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
20 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
21 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
22 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
24 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
25 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
31 #include <sys/param.h>
32 #include <sys/disklabel.h>
33 #include <sys/diskmbr.h>
46 #define MBRSIZE 512 /* master boot record size */
48 #define OFF_VERSION 0x1b0 /* offset: version number, only boot0version */
49 #define OFF_SERIAL 0x1b8 /* offset: volume serial number */
50 #define OFF_PTBL 0x1be /* offset: partition table */
51 #define OFF_MAGIC 0x1fe /* offset: magic number */
53 * Offsets to the parameters of the 512-byte boot block.
54 * For historical reasons they are set as macros
63 static struct opt_offsets b0_ofs[] = {
64 { 0x0, 0x0, 0x0, 0x0 }, /* no boot block */
65 { 0x1b9, 0x1ba, 0x1bb, 0x1bc }, /* original block */
66 { 0x1b5, 0x1b6, 0x1b7, 0x1bc }, /* NT_SERIAL block */
69 static int b0_ver; /* boot block version set by boot0bs */
71 #define OFF_OPT (b0_ofs[b0_ver].opt) /* default boot option */
72 #define OFF_DRIVE (b0_ofs[b0_ver].drive) /* setdrv drive */
73 #define OFF_FLAGS (b0_ofs[b0_ver].flags) /* option flags */
74 #define OFF_TICKS (b0_ofs[b0_ver].ticks) /* clock ticks */
77 #define cv2(p) ((p)[0] | (p)[1] << 010)
80 (p)[0] = (u_int8_t)(x), \
81 (p)[1] = (u_int8_t)((x) >> 010)
91 static const int nopt = sizeof(opttbl) / sizeof(opttbl[0]);
93 static const char fmt0[] = "# flag start chs type"
94 " end chs offset size\n";
96 static const char fmt1[] = "%d 0x%02x %4u:%3u:%2u 0x%02x"
97 " %4u:%3u:%2u %10u %10u\n";
99 static int geom_class_available(const char *);
100 static int read_mbr(const char *, u_int8_t **, int);
101 static void write_mbr(const char *, int, u_int8_t *, int);
102 static void display_mbr(u_int8_t *);
103 static int boot0version(const u_int8_t *);
104 static int boot0bs(const u_int8_t *);
105 static void stropt(const char *, int *, int *);
106 static int argtoi(const char *, int, int, int);
107 static int set_bell(u_int8_t *, int, int);
108 static void usage(void);
110 static unsigned vol_id[5]; /* 4 plus 1 for flag */
114 * Boot manager installation/configuration utility.
117 main(int argc, char *argv[])
119 u_int8_t *mbr, *boot0;
120 int boot0_size, mbr_size;
121 const char *bpath, *fpath;
124 int d_arg, m_arg, s_arg, t_arg;
125 int o_and, o_or, o_e = -1;
128 bpath = "/boot/boot0";
130 B_flag = v_flag = o_flag = 0;
131 d_arg = m_arg = s_arg = t_arg = -1;
134 while ((c = getopt(argc, argv, "Bvb:d:e:f:i:m:o:s:t:")) != -1)
146 d_arg = argtoi(optarg, 0, 0xff, 'd');
149 if (optarg[0] == '0' && optarg[1] == 'x')
150 sscanf(optarg, "0x%02x", &o_e);
158 if (sscanf(optarg, "%02x%02x-%02x%02x",
159 vol_id, vol_id+1, vol_id+2, vol_id+3) == 4)
162 errx(1, "bad argument %s", optarg);
165 m_arg = argtoi(optarg, 0, 0xf, 'm');
168 stropt(optarg, &o_and, &o_or);
172 if (strcasecmp(optarg, "pxe") == 0)
175 s_arg = argtoi(optarg, 1, 6, 's');
178 t_arg = argtoi(optarg, 1, 0xffff, 't');
187 disk = g_device_path(*argv);
189 errx(1, "Unable to get providername for %s\n", *argv);
190 up = B_flag || d_arg != -1 || m_arg != -1 || o_flag || s_arg != -1
193 /* open the disk and read in the existing mbr. Either here or
194 * when reading the block from disk, we do check for the version
195 * and abort if a suitable block is not found.
197 mbr_size = read_mbr(disk, &mbr, !B_flag);
199 /* save the existing MBR if we are asked to do so */
201 write_mbr(fpath, O_CREAT | O_TRUNC, mbr, mbr_size);
204 * If we are installing the boot loader, read it from disk and copy the
205 * slice table over from the existing MBR. If not, then point boot0
206 * back at the MBR we just read in. After this, boot0 is the data to
207 * write back to disk if we are going to do a write.
210 boot0_size = read_mbr(bpath, &boot0, 1);
211 memcpy(boot0 + OFF_PTBL, mbr + OFF_PTBL,
212 sizeof(struct dos_partition) * NDOSPART);
213 if (b0_ver == 2) /* volume serial number support */
214 memcpy(boot0 + OFF_SERIAL, mbr + OFF_SERIAL, 4);
217 boot0_size = mbr_size;
222 boot0[OFF_DRIVE] = d_arg;
224 /* set various flags */
226 boot0[OFF_FLAGS] &= 0xf0;
227 boot0[OFF_FLAGS] |= m_arg;
230 boot0[OFF_FLAGS] &= o_and;
231 boot0[OFF_FLAGS] |= o_or;
234 /* set the default boot selection */
236 boot0[OFF_OPT] = s_arg - 1;
238 /* set the timeout */
240 mk2(boot0 + OFF_TICKS, t_arg);
242 /* set the bell char */
243 if (o_e != -1 && set_bell(boot0, o_e, 0) != -1)
248 errx(1, "incompatible boot block, cannot set volume ID");
249 boot0[OFF_SERIAL] = vol_id[0];
250 boot0[OFF_SERIAL+1] = vol_id[1];
251 boot0[OFF_SERIAL+2] = vol_id[2];
252 boot0[OFF_SERIAL+3] = vol_id[3];
253 up = 1; /* force update */
255 /* write the MBR back to disk */
257 write_mbr(disk, 0, boot0, boot0_size);
259 /* display the MBR */
272 /* get or set the 'bell' character to be used in case of errors.
273 * Lookup for a certain code sequence, return -1 if not found.
276 set_bell(u_int8_t *mbr, int new_bell, int report)
278 /* lookup sequence: 0x100 means skip, 0x200 means done */
279 static unsigned seq[] =
280 { 0xb0, 0x100, 0xe8, 0x100, 0x100, 0x30, 0xe4, 0x200 };
282 for (ofs = 0x60; ofs < 0x180; ofs++) { /* search range */
283 if (mbr[ofs] != seq[0]) /* search initial pattern */
286 if (seq[i] == 0x200) { /* found */
289 mbr[ofs+1] = c = new_bell;
291 printf(" bell=%c (0x%x)",
292 (c >= ' ' && c < 0x7f) ? c : ' ', c);
295 if (seq[i] != 0x100 && seq[i] != mbr[ofs+i])
299 warn("bell not found");
303 * Read in the MBR of the disk. If it is boot0, then use the version to
304 * read in all of it if necessary. Use pointers to return a malloc'd
305 * buffer containing the MBR and then return its size.
308 read_mbr(const char *disk, u_int8_t **mbr, int check_version)
310 u_int8_t buf[MBRSIZE];
315 if ((fd = open(disk, O_RDONLY)) == -1)
316 err(1, "open %s", disk);
317 if ((n = read(fd, buf, MBRSIZE)) == -1)
318 err(1, "read %s", disk);
320 errx(1, "%s: short read", disk);
321 if (cv2(buf + OFF_MAGIC) != 0xaa55)
322 errx(1, "%s: bad magic", disk);
324 if (! (ver = boot0bs(buf))) {
326 errx(1, "%s: unknown or incompatible boot code", disk);
327 } else if (boot0version(buf) == 0x101) {
329 if ((*mbr = malloc(mbr_size)) == NULL)
330 errx(1, "%s: unable to allocate read buffer", disk);
331 if (lseek(fd, 0, SEEK_SET) == -1 ||
332 (n = read(fd, *mbr, mbr_size)) == -1)
335 errx(1, "%s: short read", disk);
339 *mbr = malloc(sizeof(buf));
340 memcpy(*mbr, buf, sizeof(buf));
347 geom_class_available(const char *name)
349 struct gclass *class;
353 error = geom_gettree(&mesh);
355 errc(1, error, "Cannot get GEOM tree");
357 LIST_FOREACH(class, &mesh.lg_class, lg_class) {
358 if (strcmp(class->lg_name, name) == 0) {
359 geom_deletetree(&mesh);
364 geom_deletetree(&mesh);
369 * Write out the mbr to the specified file.
372 write_mbr(const char *fname, int flags, u_int8_t *mbr, int mbr_size)
374 struct gctl_req *grq;
380 fd = open(fname, O_WRONLY | flags, 0666);
382 n = write(fd, mbr, mbr_size);
385 errx(1, "%s: short write", fname);
390 * If we're called to write to a backup file, don't try to
391 * write through GEOM.
394 err(1, "can't open file %s to write backup", fname);
396 /* Try open it read only. */
397 fd = open(fname, O_RDONLY);
399 warn("error opening %s", fname);
403 pname = g_providername(fd);
405 warn("error getting providername for %s", fname);
409 /* First check that GEOM_PART is available */
410 if (geom_class_available("PART") != 0) {
411 grq = gctl_get_handle();
412 gctl_ro_param(grq, "class", -1, "PART");
413 gctl_ro_param(grq, "arg0", -1, pname);
414 gctl_ro_param(grq, "verb", -1, "bootcode");
415 gctl_ro_param(grq, "bootcode", mbr_size, mbr);
416 gctl_ro_param(grq, "flags", -1, "C");
417 errmsg = gctl_issue(grq);
418 if (errmsg != NULL && errmsg[0] != '\0')
419 errx(1, "GEOM_PART: write bootcode to %s failed: %s",
422 } else if (geom_class_available("MBR") != 0) {
423 grq = gctl_get_handle();
424 gctl_ro_param(grq, "verb", -1, "write MBR");
425 gctl_ro_param(grq, "class", -1, "MBR");
426 gctl_ro_param(grq, "geom", -1, pname);
427 gctl_ro_param(grq, "data", mbr_size, mbr);
428 errmsg = gctl_issue(grq);
430 err(1, "GEOM_MBR: write MBR to %s failed", fname);
433 errx(1, "can't write MBR to %s", fname);
438 * Outputs an informative dump of the data in the MBR to stdout.
441 display_mbr(u_int8_t *mbr)
443 struct dos_partition *part;
446 part = (struct dos_partition *)(mbr + DOSPARTOFF);
448 for (i = 0; i < NDOSPART; i++)
450 printf(fmt1, 1 + i, part[i].dp_flag,
451 part[i].dp_scyl + ((part[i].dp_ssect & 0xc0) << 2),
452 part[i].dp_shd, part[i].dp_ssect & 0x3f, part[i].dp_typ,
453 part[i].dp_ecyl + ((part[i].dp_esect & 0xc0) << 2),
454 part[i].dp_ehd, part[i].dp_esect & 0x3f, part[i].dp_start,
457 version = boot0version(mbr);
458 printf("version=%d.%d drive=0x%x mask=0x%x ticks=%u",
459 version >> 8, version & 0xff, mbr[OFF_DRIVE],
460 mbr[OFF_FLAGS] & 0xf, cv2(mbr + OFF_TICKS));
462 printf("\noptions=");
463 for (i = 0; i < nopt; i++) {
466 if (!(mbr[OFF_FLAGS] & 1 << (7 - i)) ^ opttbl[i].def)
468 printf("%s", opttbl[i].tok);
472 printf("volume serial ID %02x%02x-%02x%02x\n",
473 mbr[OFF_SERIAL], mbr[OFF_SERIAL+1],
474 mbr[OFF_SERIAL+2], mbr[OFF_SERIAL+3]);
475 printf("default_selection=F%d (", mbr[OFF_OPT] + 1);
476 if (mbr[OFF_OPT] < 4)
477 printf("Slice %d", mbr[OFF_OPT] + 1);
478 else if (mbr[OFF_OPT] == 4)
486 * Return the boot0 version with the minor revision in the low byte, and
487 * the major revision in the next higher byte.
490 boot0version(const u_int8_t *bs)
492 /* Check for old version, and return 0x100 if found. */
497 /* We have a newer boot0, so extract the version number and return it. */
498 return *(const int *)(bs + OFF_VERSION) & 0xffff;
501 /* descriptor of a pattern to match.
502 * Start from the first entry trying to match the chunk of bytes,
503 * if you hit an entry with len=0 terminate the search and report
504 * off as the version. Otherwise skip to the next block after len=0
505 * An entry with len=0, off=0 is the end marker.
507 struct byte_pattern {
514 * Decide if we have valid boot0 boot code by looking for
515 * characteristic byte sequences at fixed offsets.
518 boot0bs(const u_int8_t *bs)
520 /* the initial code sequence */
521 static u_int8_t id0[] = {0xfc, 0x31, 0xc0, 0x8e, 0xc0, 0x8e, 0xd8,
522 0x8e, 0xd0, 0xbc, 0x00, 0x7c };
524 static u_int8_t id1[] = {'D', 'r', 'i', 'v', 'e', ' '};
525 static struct byte_pattern patterns[] = {
526 {0x0, sizeof(id0), id0},
527 {0x1b2, sizeof(id1), id1},
529 {0x0, sizeof(id0), id0}, /* version with NT support */
530 {0x1ae, sizeof(id1), id1},
534 struct byte_pattern *p = patterns;
536 for (; p->off || p->len; p++) {
539 if (!memcmp(bs + p->off, p->key, p->len)) /* match */
541 while (p->len) /* skip to next block */
544 b0_ver = p->off; /* XXX ugly side effect */
549 * Adjust "and" and "or" masks for a -o option argument.
552 stropt(const char *arg, int *xa, int *xo)
558 if (!(s = strdup(arg)))
560 for (s1 = s; (q = strtok(s1, ",")); s1 = NULL) {
561 if ((inv = !strncmp(q, "no", 2)))
563 for (i = 0; i < nopt; i++)
564 if (!strcmp(q, opttbl[i].tok))
567 errx(1, "%s: Unknown -o option", q);
580 * Convert and check an option argument.
583 argtoi(const char *arg, int lo, int hi, int opt)
589 x = strtol(arg, &s, 0);
590 if (errno || !*arg || *s || x < lo || x > hi)
591 errx(1, "%s: Bad argument to -%c option", arg, opt);
596 * Display usage information.
601 fprintf(stderr, "%s\n%s\n",
602 "usage: boot0cfg [-Bv] [-b boot0] [-d drive] [-f file] [-m mask]",
603 " [-o options] [-s slice] [-t ticks] disk");