xref: /netbsd-src/sbin/fdisk/fdisk.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: fdisk.c,v 1.145 2013/04/14 22:48:22 jakllsch Exp $ */
2 
3 /*
4  * Mach Operating System
5  * Copyright (c) 1992 Carnegie Mellon University
6  * All Rights Reserved.
7  *
8  * Permission to use, copy, modify and distribute this software and its
9  * documentation is hereby granted, provided that both the copyright
10  * notice and this permission notice appear in all copies of the
11  * software, derivative works or modified versions, and any portions
12  * thereof, and that both notices appear in supporting documentation.
13  *
14  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17  *
18  * Carnegie Mellon requests users of this software to return to
19  *
20  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21  *  School of Computer Science
22  *  Carnegie Mellon University
23  *  Pittsburgh PA 15213-3890
24  *
25  * any improvements or extensions that they make and grant Carnegie Mellon
26  * the rights to redistribute these changes.
27  */
28 
29 /*
30  * 14-Dec-89  Robert Baron (rvb) at Carnegie-Mellon University
31  *	Copyright (c) 1989	Robert. V. Baron
32  *	Created.
33  */
34 
35 #if HAVE_NBTOOL_CONFIG_H
36 #include "nbtool_config.h"
37 #endif
38 
39 #include <sys/cdefs.h>
40 
41 #ifndef lint
42 __RCSID("$NetBSD: fdisk.c,v 1.145 2013/04/14 22:48:22 jakllsch Exp $");
43 #endif /* not lint */
44 
45 #define MBRPTYPENAMES
46 #include <sys/types.h>
47 #include <sys/param.h>
48 #include <sys/stat.h>
49 #include <ctype.h>
50 #include <err.h>
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <paths.h>
54 #include <stdarg.h>
55 #include <stddef.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <unistd.h>
60 #include <vis.h>
61 
62 #if !HAVE_NBTOOL_CONFIG_H
63 #include <sys/disklabel.h>
64 #include <sys/disklabel_gpt.h>
65 #include <sys/bootblock.h>
66 #include <sys/ioctl.h>
67 #include <sys/sysctl.h>
68 #include <disktab.h>
69 #include <util.h>
70 #include <zlib.h>
71 #else
72 #include <nbinclude/sys/disklabel.h>
73 #include <nbinclude/sys/disklabel_gpt.h>
74 #include <nbinclude/sys/bootblock.h>
75 #include "../../include/disktab.h"
76 /* We enforce -F, so none of these possibly undefined items can be needed */
77 #define opendisk(path, fl, buf, buflen, cooked) (-1)
78 #ifndef DIOCGDEFLABEL
79 #define DIOCGDEFLABEL 0
80 #endif
81 #ifndef DIOCGDINFO
82 #define DIOCGDINFO 0
83 #endif
84 #ifndef DIOCWLABEL
85 #define DIOCWLABEL 0
86 #endif
87 #endif /* HAVE_NBTOOL_CONFIG_H */
88 
89 #ifndef	DEFAULT_BOOTDIR
90 #define	DEFAULT_BOOTDIR		"/usr/mdec"
91 #endif
92 
93 #define	LE_MBR_MAGIC		htole16(MBR_MAGIC)
94 #define	LE_MBR_BS_MAGIC		htole16(MBR_BS_MAGIC)
95 
96 #ifdef BOOTSEL
97 
98 #define	DEFAULT_BOOTCODE	"mbr"
99 #define	DEFAULT_BOOTSELCODE	"mbr_bootsel"
100 #define	DEFAULT_BOOTEXTCODE	"mbr_ext"
101 
102 /* Scan values for the various keys we use, as returned by the BIOS */
103 #define	SCAN_ENTER	0x1c
104 #define	SCAN_F1		0x3b
105 #define	SCAN_1		0x2
106 
107 
108 #define	MAX_BIOS_DISKS	16	/* Going beyond F12 is hard though! */
109 
110 /* We same the dflt 'boot partition' as a disk block, with some magic values. */
111 #define DEFAULT_ACTIVE	(~(daddr_t)0)
112 #define	DEFAULT_DISK(n)	(DEFAULT_ACTIVE - MAX_BIOS_DISKS + (n))
113 
114 #endif
115 
116 #define GPT_TYPE(offs) ((offs) == GPT_HDR_BLKNO ?  "primary" : "secondary")
117 
118 #ifndef PRIdaddr
119 #define PRIdaddr PRId64
120 #endif
121 
122 #ifndef _PATH_DEFDISK
123 #define _PATH_DEFDISK	"/dev/rwd0d"
124 #endif
125 
126 struct {
127 	struct mbr_sector *ptn;		/* array of pbrs */
128 	daddr_t		base;		/* first sector of ext. ptn */
129 	daddr_t		limit;		/* last sector of ext. ptn */
130 	int		num_ptn;	/* number of contained partitions */
131 	int		ptn_id;		/* entry in mbr */
132 	int		is_corrupt;	/* 1 if extended chain illegal */
133 } ext;
134 
135 #define LBUF 100
136 static char lbuf[LBUF];
137 
138 static const char *disk = _PATH_DEFDISK;
139 
140 static struct disklabel disklabel;		/* disk parameters */
141 
142 static struct mbr_sector mboot;
143 
144 static const char *boot_dir = DEFAULT_BOOTDIR;
145 static char *boot_path = NULL;			/* name of file we actually opened */
146 
147 #ifdef BOOTSEL
148 #define BOOTSEL_OPTIONS	"B"
149 #else
150 #define BOOTSEL_OPTIONS
151 #define change_part(e, p, id, st, sz, bm) change__part(e, p, id, st, sz)
152 #endif
153 #define OPTIONS	BOOTSEL_OPTIONS "0123FSafiIluvA:b:c:E:r:s:w:z:"
154 
155 /*
156  * Disk geometry and partition alignment.
157  *
158  * Modern disks do not have a fixed geomery and will always give a 'faked'
159  * geometry that matches the ATA standard - max 16 heads and 256 sec/track.
160  * The ATA geometry allows access to 2^28 sectors (as does LBA mode).
161  *
162  * The BIOS calls originally used an 8bit register for cylinder, head and
163  * sector. Later 2 bits were stolen from the sector number and added to
164  * cylinder number. The BIOS will translate this faked geometry either to
165  * the geometry reported by the disk, or do LBA reads (possibly LBA48).
166  * BIOS CHS reads have all sorts of limits, but 2^24 is absolute.
167  * For historic reasons the BIOS geometry is the called the dos geometry!
168  *
169  * If you know the disks real geometry it is usually worth aligning
170  * disk partitions to cylinder boundaries (certainly traditional!).
171  * For 'mbr' disks this has always been done with the BIOS geometry.
172  * The first track (typically 63 sectors) is reserved because the first
173  * sector is used for boot code. Similarly the data partition in an
174  * extended partition will start one track in. If an extended partition
175  * starts at the beginning of the disk you lose 2 tracks.
176  *
177  * However non-magnetic media in particular has physical sectors that are
178  * not the same size as those reported, so has to do read modify write
179  * sequences for misaligned transfers. The alignment of partitions to
180  * cylinder boundaries makes this happen all the time.
181  *
182  * It is thus sensible to align partitions on a sensible sector boundary.
183  * For instance 1MB (2048 sectors).
184  * Common code can do this by using a geometry with 1 head and 2048
185  * sectors per track.
186  */
187 
188 /* Disks reported geometry and overall size from device driver */
189 static unsigned int cylinders, sectors, heads;
190 static daddr_t disksectors;
191 #define cylindersectors (heads * sectors)
192 
193 /* Geometry from the BIOS */
194 static unsigned int dos_cylinders;
195 static unsigned int dos_heads;
196 static unsigned int dos_sectors;
197 static daddr_t dos_disksectors;
198 #define dos_cylindersectors (dos_heads * dos_sectors)
199 #define dos_totalsectors (dos_heads * dos_sectors * dos_cylinders)
200 
201 #define DOSSECT(s,c)	(((s) & 0x3f) | (((c) >> 2) & 0xc0))
202 #define DOSCYL(c)	((c) & 0xff)
203 #define SEC_IN_1M (1024 * 1024 / secsize)
204 #define SEC_TO_MB(sec) ((unsigned int)(((sec) + SEC_IN_1M / 2) / SEC_IN_1M))
205 #define SEC_TO_CYL(sec) (((sec) + dos_cylindersectors/2) / dos_cylindersectors)
206 
207 #define MAXCYL		1024	/* Usual limit is 1023 */
208 #define	MAXHEAD		256	/* Usual limit is 255 */
209 #define	MAXSECTOR	63
210 static int partition = -1;
211 
212 /* Alignment of partition, and offset if first sector unusable */
213 static unsigned int ptn_alignment;	/* default dos_cylindersectors */
214 static unsigned int ptn_0_offset;	/* default dos_sectors */
215 
216 static int fd = -1, wfd = -1, *rfd = &fd;
217 static char *disk_file = NULL;
218 static char *disk_type = NULL;
219 
220 static int a_flag;		/* set active partition */
221 static int i_flag;		/* init bootcode */
222 static int I_flag;		/* ignore errors */
223 static int u_flag;		/* update partition data */
224 static int v_flag;		/* more verbose */
225 static int sh_flag;		/* Output data as shell defines */
226 static int f_flag;		/* force --not interactive */
227 static int s_flag;		/* set id,offset,size */
228 static int b_flag;		/* Set cyl, heads, secs (as c/h/s) */
229 static int B_flag;		/* Edit/install bootselect code */
230 static int E_flag;		/* extended partition number */
231 static int b_cyl, b_head, b_sec;  /* b_flag values. */
232 
233 #if !HAVE_NBTOOL_CONFIG_H
234 static int F_flag = 0;
235 #else
236 /* Tool - force 'file' mode to avoid unsupported functions and ioctls */
237 static int F_flag = 1;
238 #endif
239 
240 static struct gpt_hdr gpt1, gpt2;	/* GUID partition tables */
241 
242 static struct mbr_sector bootcode[8192 / sizeof (struct mbr_sector)];
243 static ssize_t secsize = 512;	/* sector size */
244 static char *iobuf;		/* buffer for non 512 sector I/O */
245 static int bootsize;		/* actual size of bootcode */
246 static int boot_installed;	/* 1 if we've copied code into the mbr */
247 
248 #if defined(USE_DISKLIST)
249 #include <machine/cpu.h>
250 static struct disklist *dl;
251 #endif
252 
253 
254 #define KNOWN_SYSIDS	(sizeof(mbr_ptypes)/sizeof(mbr_ptypes[0]))
255 
256 __dead static void	usage(void);
257 static void	print_s0(int);
258 static void	print_part(struct mbr_sector *, int, daddr_t);
259 static void	print_mbr_partition(struct mbr_sector *, int, daddr_t, daddr_t, int);
260 static void	print_pbr(daddr_t, int, uint8_t);
261 static int	is_all_zero(const unsigned char *, size_t);
262 static void	printvis(int, const char *, const char *, size_t);
263 static int	read_boot(const char *, void *, size_t, int);
264 static void	init_sector0(int);
265 static void	intuit_translated_geometry(void);
266 static void	get_bios_geometry(void);
267 static void	get_extended_ptn(void);
268 static void	get_ptn_alignmemt(void);
269 #if defined(USE_DISKLIST)
270 static void	get_diskname(const char *, char *, size_t);
271 #endif
272 static int	change_part(int, int, int, daddr_t, daddr_t, char *);
273 static void	print_geometry(void);
274 static int	first_active(void);
275 static void	change_active(int);
276 static void	change_bios_geometry(void);
277 static void	dos(int, unsigned char *, unsigned char *, unsigned char *);
278 static int	open_disk(int);
279 static ssize_t	read_disk(daddr_t, void *);
280 static ssize_t	write_disk(daddr_t, void *);
281 static int	get_params(void);
282 static int	read_s0(daddr_t, struct mbr_sector *);
283 static int	write_mbr(void);
284 static int	read_gpt(daddr_t, struct gpt_hdr *);
285 static int	delete_gpt(struct gpt_hdr *);
286 static int	yesno(const char *, ...) __printflike(1, 2);
287 static int64_t	decimal(const char *, int64_t, int, int64_t, int64_t);
288 #define DEC_SEC		1		/* asking for a sector number */
289 #define	DEC_RND		2		/* round to end of first track */
290 #define	DEC_RND_0	4		/* convert 0 to size of a track */
291 #define DEC_RND_DOWN	8		/* subtract 1 track */
292 #define DEC_RND_DOWN_2	16		/* subtract 2 tracks */
293 static int	ptn_id(const char *, int *);
294 static int	type_match(const void *, const void *);
295 static const char *get_type(int);
296 static int	get_mapping(int, unsigned int *, unsigned int *, unsigned int *, unsigned long *);
297 #ifdef BOOTSEL
298 static daddr_t	configure_bootsel(daddr_t);
299 static void	install_bootsel(int);
300 static daddr_t	get_default_boot(void);
301 static void	set_default_boot(daddr_t);
302 static void	string(const char *, int, char *);
303 #endif
304 
305 static void
306 initvar_disk(const char **diskp)
307 {
308 #if !HAVE_NBTOOL_CONFIG_H
309 	int mib[2];
310 	size_t len;
311 	char *root_device;
312 
313 	mib[0] = CTL_KERN;
314 	mib[1] = KERN_ROOT_DEVICE;
315 	if (sysctl(mib, 2, NULL, &len, NULL, 0) == -1 ||
316 	    (root_device = malloc(len)) == NULL ||
317 	    sysctl(mib, 2, root_device, &len, NULL, 0) == -1)
318 		return;
319 
320 	*diskp = root_device;
321 #endif /* HAVE_NBTOOL_CONFIG_H */
322 }
323 
324 int
325 main(int argc, char *argv[])
326 {
327 	struct stat sb;
328 	int ch;
329 	size_t len;
330 	char *cp;
331 	int n;
332 #ifdef BOOTSEL
333 	daddr_t default_ptn;		/* start sector of default ptn */
334 	char *cbootmenu = 0;
335 #endif
336 
337 	int csysid;	/* For the s_flag. */
338 	unsigned int cstart, csize;
339 	a_flag = u_flag = sh_flag = f_flag = s_flag = b_flag = 0;
340 	i_flag = B_flag = 0;
341 	v_flag = 0;
342 	E_flag = 0;
343 	csysid = cstart = csize = 0;
344 	while ((ch = getopt(argc, argv, OPTIONS)) != -1) {
345 		switch (ch) {
346 		case '0':
347 			partition = 0;
348 			break;
349 		case '1':
350 			partition = 1;
351 			break;
352 		case '2':
353 			partition = 2;
354 			break;
355 		case '3':
356 			partition = 3;
357 			break;
358 		case 'E':	/* Extended partition number */
359 			E_flag = 1;
360 			partition = strtoul(optarg, &cp, 0);
361 			if (*cp || partition < 0)
362 				errx(1, "Bad partition number -E %s.", optarg);
363 			break;
364 #ifdef BOOTSEL
365 		case 'B':	/* Bootselect parameters */
366 			B_flag = 1;
367 			break;
368 #endif
369 		case 'F':	/* device argument is really a file */
370 			F_flag = 1;
371 			break;
372 		case 'S':	/* Output as shell variables */
373 			sh_flag = 1;
374 			break;
375 		case 'a':	/* Set active partition */
376 			a_flag = 1;
377 			break;
378 		case 'f':	/* Non interactive */
379 			f_flag = 1;
380 			break;
381 		case 'i':	/* Always update bootcode */
382 			i_flag = 1;
383 			break;
384 		case 'I':	/* Ignore errors */
385 			I_flag = 1;
386 			break;
387 		case 'l':	/* List known partition types */
388 			for (len = 0; len < KNOWN_SYSIDS; len++)
389 				printf("%03d %s\n", mbr_ptypes[len].id,
390 				    mbr_ptypes[len].name);
391 			return 0;
392 		case 'u':	/* Update partition details */
393 			u_flag = 1;
394 			break;
395 		case 'v':	/* Be verbose */
396 			v_flag++;
397 			break;
398 		case 's':	/* Partition details */
399 			s_flag = 1;
400 			if (sscanf(optarg, "%d/%u/%u%n", &csysid, &cstart,
401 			    &csize, &n) == 3) {
402 				if (optarg[n] == 0)
403 					break;
404 #ifdef BOOTSEL
405 				if (optarg[n] == '/') {
406 					cbootmenu = optarg + n + 1;
407 					break;
408 				}
409 #endif
410 			}
411 			errx(1, "Bad argument to the -s flag.");
412 			break;
413 		case 'b':	/* BIOS geometry */
414 			b_flag = 1;
415 			if (sscanf(optarg, "%d/%d/%d%n", &b_cyl, &b_head,
416 			    &b_sec, &n) != 3 || optarg[n] != 0)
417 				errx(1, "Bad argument to the -b flag.");
418 			if (b_cyl > MAXCYL)
419 				b_cyl = MAXCYL;
420 			break;
421 		case 'A':	/* Partition alignment[/offset] */
422 			if (sscanf(optarg, "%u%n/%u%n", &ptn_alignment,
423 				    &n, &ptn_0_offset, &n) < 1
424 			    || optarg[n] != 0
425 			    || ptn_0_offset > ptn_alignment)
426 				errx(1, "Bad argument to the -A flag.");
427 			if (ptn_0_offset == 0)
428 				ptn_0_offset = ptn_alignment;
429 			break;
430 		case 'c':	/* file/directory containing boot code */
431 			if (strchr(optarg, '/') != NULL &&
432 			    stat(optarg, &sb) == 0 &&
433 			    (sb.st_mode & S_IFMT) == S_IFDIR) {
434 				boot_dir = optarg;
435 				break;
436 			}
437 			bootsize = read_boot(optarg, bootcode,
438 						sizeof bootcode, 1);
439 			i_flag = 1;
440 			break;
441 		case 'r':	/* read data from disk_file (not raw disk) */
442 			rfd = &wfd;
443 			/* FALLTHROUGH */
444 		case 'w':	/* write data to disk_file */
445 			disk_file = optarg;
446 			break;
447 		case 't':
448 			if (setdisktab(optarg) == -1)
449 				errx(EXIT_FAILURE, "bad disktab");
450 			break;
451 		case 'T':
452 			disk_type = optarg;
453 			break;
454 		case 'z':
455 			secsize = atoi(optarg);
456 			if (secsize <= 512)
457 out:				 errx(EXIT_FAILURE, "Invalid sector size %zd",
458 				    secsize);
459 			for (ch = secsize; (ch & 1) == 0; ch >>= 1)
460 				continue;
461 			if (ch != 1)
462 				goto out;
463 			break;
464 		default:
465 			usage();
466 		}
467 	}
468 	argc -= optind;
469 	argv += optind;
470 
471 	if (disk_type != NULL && getdiskbyname(disk_type) == NULL)
472 		errx(EXIT_FAILURE, "bad disktype");
473 
474 	if (sh_flag && (a_flag || i_flag || u_flag || f_flag || s_flag))
475 		usage();
476 
477 	if (B_flag && f_flag) {
478 		warnx("Bootselector may only be configured interactively");
479 		usage();
480 	}
481 
482 	if (f_flag && u_flag && !s_flag) {
483 		warnx("Partition data not specified");
484 		usage();
485 	}
486 
487 	if (s_flag && partition == -1) {
488 		warnx("-s flag requires a partition selected.");
489 		usage();
490 	}
491 
492 	if (argc > 1)
493 		usage();
494 
495 	if (argc > 0)
496 		disk = argv[0];
497 	else if (!F_flag) {
498 		/* Default to boot device */
499 		initvar_disk(&disk);
500 	}
501 
502 	if (!F_flag && stat(disk, &sb) == 0 && S_ISREG(sb.st_mode))
503 		F_flag = 1;
504 
505 	if (open_disk(B_flag || a_flag || i_flag || u_flag) < 0)
506 		exit(1);
507 
508 	if (secsize > 512) {
509 		if ((iobuf = malloc(secsize)) == NULL)
510 			err(EXIT_FAILURE, "Cannot allocate %zd buffer",
511 			    secsize);
512 	}
513 
514 	if (read_s0(0, &mboot))
515 		/* must have been a blank disk */
516 		init_sector0(1);
517 
518 	read_gpt(GPT_HDR_BLKNO, &gpt1);
519 	read_gpt(disksectors - 1, &gpt2);
520 
521 	if (b_flag) {
522 		dos_cylinders = b_cyl;
523 		dos_heads = b_head;
524 		dos_sectors = b_sec;
525 	} else {
526 		get_bios_geometry();
527 	}
528 
529 	if (ptn_alignment == 0)
530 		get_ptn_alignmemt();
531 
532 	get_extended_ptn();
533 
534 #ifdef BOOTSEL
535 	default_ptn = get_default_boot();
536 #endif
537 
538 	if (E_flag && !u_flag && partition >= ext.num_ptn)
539 		errx(1, "Extended partition %d is not defined.", partition);
540 
541 	/* Do the update stuff! */
542 	if (u_flag) {
543 		if (!f_flag && !b_flag)
544 			change_bios_geometry();
545 
546 		if (s_flag)
547 			change_part(E_flag, partition, csysid, cstart, csize,
548 				cbootmenu);
549 		else {
550 			int part = partition, chg_ext = E_flag, prompt = 1;
551 			do {
552 				if (prompt) {
553 					printf("\n");
554 					print_s0(partition);
555 				}
556 				if (partition == -1)
557 					part = ptn_id(
558 				    "Which partition do you want to change?",
559 							&chg_ext);
560 				if (part < 0)
561 					break;
562 				prompt = change_part(chg_ext, part, 0, 0, 0, 0);
563 			} while (partition == -1);
564 		}
565 	} else {
566 		if (!i_flag && !B_flag) {
567 			print_geometry();
568 			print_s0(partition);
569 		}
570 	}
571 
572 	if (a_flag && !E_flag)
573 		change_active(partition);
574 
575 #ifdef BOOTSEL
576 	if (B_flag || u_flag || i_flag)
577 		/* Ensure the mbr code supports this configuration */
578 		install_bootsel(0);
579 	if (B_flag)
580 		default_ptn = configure_bootsel(default_ptn);
581 	set_default_boot(default_ptn);
582 #else
583 	if (i_flag)
584 		init_sector0(0);
585 #endif
586 
587 	if (u_flag || a_flag || i_flag || B_flag) {
588 		if (!f_flag) {
589 			printf("\nWe haven't written the MBR back to disk "
590 			       "yet.  This is your last chance.\n");
591 			if (u_flag)
592 				print_s0(-1);
593 			if (gpt1.hdr_size != 0 || gpt2.hdr_size != 0)
594 				printf("\nWARNING: The disk is carrying "
595 				       "GUID Partition Tables.\n"
596 				       "         If you continue, "
597 				       "GPT headers will be deleted.\n\n");
598 			if (yesno("Should we write new partition table?")) {
599 				delete_gpt(&gpt1);
600 				delete_gpt(&gpt2);
601 				write_mbr();
602 			}
603 		} else {
604 			if (delete_gpt(&gpt1) > 0)
605 				warnx("Primary GPT header was deleted");
606 			if (delete_gpt(&gpt2) > 0)
607 				warnx("Secondary GPT header was deleted");
608 			write_mbr();
609 		}
610 	}
611 
612 	exit(0);
613 }
614 
615 static void
616 usage(void)
617 {
618 	int indent = 7 + (int)strlen(getprogname()) + 1;
619 
620 	(void)fprintf(stderr, "usage: %s [-aBFfIilSuv] "
621 		"[-A ptn_alignment[/ptn_0_offset]] \\\n"
622 		"%*s[-b cylinders/heads/sectors] \\\n"
623 		"%*s[-0123 | -E num "
624 		"[-s id/start/size[/bootmenu]]] \\\n"
625 		"%*s[-t disktab] [-T disktype] \\\n"
626 		"%*s[-c bootcode] "
627 		"[-r|-w file] [device]\n"
628 		"\t-a change active partition\n"
629 		"\t-f force - not interactive\n"
630 		"\t-i initialise MBR code\n"
631 		"\t-I ignore errors about no space or overlapping partitions\n"
632 		"\t-l list partition types\n"
633 		"\t-u update partition data\n"
634 		"\t-v verbose output, -v -v more verbose still\n"
635 		"\t-B update bootselect options\n"
636 		"\t-F treat device as a regular file\n"
637 		"\t-S output as shell defines\n"
638 		"\t-r and -w access 'file' for non-destructive testing\n",
639 		getprogname(), indent, "", indent, "", indent, "", indent, "");
640 	exit(1);
641 }
642 
643 static daddr_t
644 ext_offset(int part)
645 {
646 	daddr_t offset = ext.base;
647 
648 	if (part != 0)
649 		offset += le32toh(ext.ptn[part - 1].mbr_parts[1].mbrp_start);
650 	return offset;
651 }
652 
653 static void
654 print_s0(int which)
655 {
656 	int part;
657 
658 	if (which == -1) {
659 		if (!sh_flag)
660 			printf("Partition table:\n");
661 		for (part = 0; part < MBR_PART_COUNT; part++) {
662 			if (!sh_flag)
663 				printf("%d: ", part);
664 			print_part(&mboot, part, 0);
665 		}
666 		if (!sh_flag) {
667 			if (ext.is_corrupt)
668 				printf("Extended partition table is corrupt\n");
669 			else
670 				if (ext.num_ptn != 0)
671 					printf("Extended partition table:\n");
672 		}
673 		for (part = 0; part < ext.num_ptn; part++) {
674 			if (!sh_flag)
675 				printf("E%d: ", part);
676 			print_part(&ext.ptn[part], 0, ext_offset(part));
677 			if (!sh_flag && v_flag >= 2) {
678 				printf("link: ");
679 				print_mbr_partition(&ext.ptn[part], 1,
680 						ext_offset(part), ext.base, 0);
681 			}
682 		}
683 #ifdef BOOTSEL
684 		if (!sh_flag && mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
685 			int tmo;
686 
687 			printf("Bootselector ");
688 			if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ACTIVE) {
689 				printf("enabled");
690 				tmo = le16toh(mboot.mbr_bootsel.mbrbs_timeo);
691 				if (tmo == 0xffff)
692 					printf(", infinite timeout");
693 				else
694 					printf(", timeout %d seconds",
695 						    (10 * tmo + 9) / 182);
696 			} else
697 				printf("disabled");
698 			printf(".\n");
699 		}
700 #endif
701 		if (!sh_flag) {
702 			int active = first_active();
703 			if (active == MBR_PART_COUNT)
704 				printf("No active partition.\n");
705 			else
706 				printf("First active partition: %d\n", active);
707 		}
708 		if (!sh_flag && mboot.mbr_dsn != 0)
709 			printf("Drive serial number: %"PRIu32" (0x%08x)\n",
710 			    le32toh(mboot.mbr_dsn),
711 			    le32toh(mboot.mbr_dsn));
712 		return;
713 	}
714 
715 	if (E_flag) {
716 		if (!sh_flag)
717 			printf("Extended partition E%d:\n", which);
718 		if (which > ext.num_ptn)
719 			printf("Undefined\n");
720 		else
721 			print_part(&ext.ptn[which], 0, ext_offset(which));
722 	} else {
723 		if (!sh_flag)
724 			printf("Partition %d:\n", which);
725 		print_part(&mboot, which, 0);
726 	}
727 }
728 
729 static void
730 print_part(struct mbr_sector *boot, int part, daddr_t offset)
731 {
732 	struct mbr_partition *partp;
733 	const char *e;
734 
735 	if (!sh_flag) {
736 		print_mbr_partition(boot, part, offset, 0, 0);
737 		return;
738 	}
739 
740 	partp = &boot->mbr_parts[part];
741 	if (boot != &mboot) {
742 		part = boot - ext.ptn;
743 		e = "E";
744 	} else
745 		e = "";
746 
747 	if (partp->mbrp_type == 0) {
748 		printf("PART%s%dSIZE=0\n", e, part);
749 		return;
750 	}
751 
752 	printf("PART%s%dID=%d\n", e, part, partp->mbrp_type);
753 	printf("PART%s%dSIZE=%u\n", e, part, le32toh(partp->mbrp_size));
754 	printf("PART%s%dSTART=%"PRIdaddr"\n", e, part,
755 	    offset + le32toh(partp->mbrp_start));
756 	printf("PART%s%dFLAG=0x%x\n", e, part, partp->mbrp_flag);
757 	printf("PART%s%dBCYL=%d\n", e, part,
758 	    MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect));
759 	printf("PART%s%dBHEAD=%d\n", e, part, partp->mbrp_shd);
760 	printf("PART%s%dBSEC=%d\n", e, part, MBR_PSECT(partp->mbrp_ssect));
761 	printf("PART%s%dECYL=%d\n", e, part,
762 	    MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect));
763 	printf("PART%s%dEHEAD=%d\n", e, part, partp->mbrp_ehd);
764 	printf("PART%s%dESEC=%d\n", e, part, MBR_PSECT(partp->mbrp_esect));
765 }
766 
767 static void
768 pr_cyls(daddr_t sector, int is_end)
769 {
770 	unsigned long cyl, head, sect;
771 	cyl = sector / dos_cylindersectors;
772 	sect = sector - cyl * dos_cylindersectors;
773 	head = sect / dos_sectors;
774 	sect -= head * dos_sectors;
775 
776 	printf("%lu", cyl);
777 
778 	if (is_end) {
779 		if (head == dos_heads - 1 && sect == dos_sectors - 1)
780 			return;
781 	} else {
782 		if (head == 0 && sect == 0)
783 			return;
784 	}
785 
786 	printf("/%lu/%lu", head, sect + 1);
787 }
788 
789 static void
790 print_mbr_partition(struct mbr_sector *boot, int part,
791     daddr_t offset, daddr_t exoffset, int indent)
792 {
793 	daddr_t	start;
794 	daddr_t	size;
795 	struct mbr_partition *partp = &boot->mbr_parts[part];
796 	struct mbr_sector eboot;
797 	int p;
798 	static int dumped = 0;
799 
800 	if (partp->mbrp_type == 0 && v_flag < 2) {
801 		printf("<UNUSED>\n");
802 		return;
803 	}
804 
805 	start = le32toh(partp->mbrp_start);
806 	size = le32toh(partp->mbrp_size);
807 	if (MBR_IS_EXTENDED(partp->mbrp_type))
808 		start += exoffset;
809 	else
810 		start += offset;
811 
812 	printf("%s (sysid %d)\n", get_type(partp->mbrp_type), partp->mbrp_type);
813 #ifdef BOOTSEL
814 	if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC &&
815 	    boot->mbr_bootsel.mbrbs_nametab[part][0])
816 		printf("%*s    bootmenu: %s\n", indent, "",
817 		    boot->mbr_bootsel.mbrbs_nametab[part]);
818 #endif
819 
820 	printf("%*s    start %"PRIdaddr", size %"PRIdaddr,
821 	    indent, "", start, size);
822 	if (size != 0) {
823 		printf(" (%u MB, Cyls ", SEC_TO_MB(size));
824 		if (v_flag == 0 && le32toh(partp->mbrp_start) == ptn_0_offset)
825 			pr_cyls(start - ptn_0_offset, 0);
826 		else
827 			pr_cyls(start, 0);
828 		printf("-");
829 		pr_cyls(start + size - 1, 1);
830 		printf(")");
831 	}
832 
833 	switch (partp->mbrp_flag) {
834 	case 0:
835 		break;
836 	case MBR_PFLAG_ACTIVE:
837 		printf(", Active");
838 		break;
839 	default:
840 		printf(", flag 0x%x", partp->mbrp_flag);
841 		break;
842 	}
843 	printf("\n");
844 
845 	if (v_flag) {
846 		printf("%*s        beg: cylinder %4d, head %3d, sector %2d\n",
847 		    indent, "",
848 		    MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect),
849 		    partp->mbrp_shd, MBR_PSECT(partp->mbrp_ssect));
850 		printf("%*s        end: cylinder %4d, head %3d, sector %2d\n",
851 		    indent, "",
852 		    MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect),
853 		    partp->mbrp_ehd, MBR_PSECT(partp->mbrp_esect));
854 	}
855 
856 	if (partp->mbrp_type == 0 && start == 0 && v_flag < 3)
857 		return;
858 
859 	if (! MBR_IS_EXTENDED(partp->mbrp_type))
860 		print_pbr(start, indent + 8, partp->mbrp_type);
861 
862 	if (!MBR_IS_EXTENDED(partp->mbrp_type) ||
863 	    (v_flag <= 2 && !ext.is_corrupt))
864 		return;
865 
866 	/*
867 	 * Recursive dump extended table,
868 	 * This is read from the disk - so is wrong during editing.
869 	 * Just ensure we only show it once.
870 	 */
871 	if (dumped)
872 		return;
873 
874 	printf("%*s    Extended partition table:\n", indent, "");
875 	indent += 4;
876 	if (read_s0(start, &eboot) == -1)
877 		return;
878 	for (p = 0; p < MBR_PART_COUNT; p++) {
879 		printf("%*s%d: ", indent, "", p);
880 		print_mbr_partition(&eboot, p, start,
881 				    exoffset ? exoffset : start, indent);
882 	}
883 
884 	if (exoffset == 0)
885 		dumped = 1;
886 }
887 
888 /* Print a line with a label and a vis-encoded string */
889 static void
890 printvis(int indent, const char *label, const char *buf, size_t size)
891 {
892 	char *visbuf;
893 
894 	if ((visbuf = malloc(size * 4 + 1)) == NULL)
895 		err(1, "Malloc failed");
896 	strsvisx(visbuf, buf, size, VIS_TAB|VIS_NL|VIS_OCTAL, "\"");
897 	printf("%*s%s: \"%s\"\n",
898 	    indent, "",
899 	    label, visbuf);
900 	free(visbuf);
901 }
902 
903 /* Check whether a buffer contains all bytes zero */
904 static int
905 is_all_zero(const unsigned char *p, size_t size)
906 {
907 
908 	while (size-- > 0) {
909 		if (*p++ != 0)
910 			return 0;
911 	}
912 	return 1;
913 }
914 
915 /*
916  * Report on the contents of a PBR sector.
917  *
918  * We first perform several sanity checks.  If vflag >= 2, we report all
919  * failing tests, but for smaller values of v_flag we stop after the
920  * first failing test.  Tests are ordered in an attempt to get the most
921  * useful error message from the first failing test.
922  *
923  * If v_flag >= 2, we also report some decoded values from the PBR.
924  * These results may be meaningless, if the PBR doesn't follow common
925  * conventions.
926  *
927  * Trying to decode anything more than the magic number in the last
928  * two bytes is a layering violation, but it can be very useful in
929  * diagnosing boot failures.
930  */
931 static void
932 print_pbr(daddr_t sector, int indent, uint8_t part_type)
933 {
934 	struct mbr_sector pboot;
935 	unsigned char *p, *endp;
936 	unsigned char val;
937 	int ok;
938 	int errcount = 0;
939 
940 #define PBR_ERROR(...)							\
941 	do {								\
942 		++errcount;						\
943 		printf("%*s%s: ", indent, "",				\
944 		    (v_flag < 2 ? "PBR is not bootable" : "Not bootable")); \
945 		printf(__VA_ARGS__);					\
946 		if (v_flag < 2)						\
947 			return;						\
948 	} while (/*CONSTCOND*/ 0)
949 
950 	if (v_flag >= 2) {
951 		printf("%*sInformation from PBR:\n",
952 		    indent, "");
953 		indent += 4;
954 	}
955 
956 	if (read_disk(sector, &pboot) == -1) {
957 		PBR_ERROR("Sector %"PRIdaddr" is unreadable (%s)\n",
958 		    sector, strerror(errno));
959 		return;
960 	}
961 
962 	/* all bytes identical? */
963 	p = (unsigned char *)&pboot;
964 	endp = p + sizeof(pboot);
965 	val = *p;
966 	ok = 0;
967 	for (; p < endp; p++) {
968 		if (*p != val) {
969 			ok = 1;
970 			break;
971 		}
972 	}
973 	if (! ok)
974 		PBR_ERROR("All bytes are identical (0x%02x)\n", val);
975 
976 	if (pboot.mbr_magic != LE_MBR_MAGIC)
977 		PBR_ERROR("Bad magic number (0x%04x)\n",
978 			le16toh(pboot.mbr_magic));
979 
980 #if 0
981 	/* Some i386 OS might fail this test.  All non-i386 will fail. */
982 	if (pboot.mbr_jmpboot[0] != 0xE9
983 	    && pboot.mbr_jmpboot[0] != 0xEB) {
984 		PBR_ERROR("Does not begin with i386 JMP instruction"
985 			" (0x%02x 0x%02x0 0x%02x)\n",
986 		    pboot.mbr_jmpboot[0], pboot.mbr_jmpboot[1],
987 		    pboot.mbr_jmpboot[2]);
988 	}
989 #endif
990 
991 	if (v_flag > 0 && errcount == 0)
992 		printf("%*sPBR appears to be bootable\n",
993 		    indent, "");
994 	if (v_flag < 2)
995 		return;
996 
997 	if (! is_all_zero(pboot.mbr_oemname, sizeof(pboot.mbr_oemname))) {
998 		printvis(indent, "OEM name", (char *)pboot.mbr_oemname,
999 			sizeof(pboot.mbr_oemname));
1000 	}
1001 
1002 	if (pboot.mbr_bpb.bpb16.bsBootSig == 0x29)
1003 		printf("%*sBPB FAT16 boot signature found\n",
1004 		    indent, "");
1005 	if (pboot.mbr_bpb.bpb32.bsBootSig == 0x29)
1006 		printf("%*sBPB FAT32 boot signature found\n",
1007 		    indent, "");
1008 
1009 #undef PBR_ERROR
1010 }
1011 
1012 static int
1013 read_boot(const char *name, void *buf, size_t len, int err_exit)
1014 {
1015 	int bfd, ret;
1016 	struct stat st;
1017 
1018 	if (boot_path != NULL)
1019 		free(boot_path);
1020 	if (strchr(name, '/') == 0)
1021 		asprintf(&boot_path, "%s/%s", boot_dir, name);
1022 	else
1023 		boot_path = strdup(name);
1024 	if (boot_path == NULL)
1025 		err(1, "Malloc failed");
1026 
1027 	if ((bfd = open(boot_path, O_RDONLY)) < 0 || fstat(bfd, &st) == -1) {
1028 		warn("%s", boot_path);
1029 		goto fail;
1030 	}
1031 
1032 	if (st.st_size > (off_t)len) {
1033 		warnx("%s: bootcode too large", boot_path);
1034 		goto fail;
1035 	}
1036 	ret = st.st_size;
1037 	if (ret < 0x200) {
1038 		warnx("%s: bootcode too small", boot_path);
1039 		goto fail;
1040 	}
1041 	if (read(bfd, buf, len) != ret) {
1042 		warn("%s", boot_path);
1043 		goto fail;
1044 	}
1045 
1046 	/*
1047 	 * Do some sanity checking here
1048 	 */
1049 	if (((struct mbr_sector *)buf)->mbr_magic != LE_MBR_MAGIC) {
1050 		warnx("%s: invalid magic", boot_path);
1051 		goto fail;
1052 	}
1053 
1054 	close(bfd);
1055 	ret = (ret + 0x1ff) & ~0x1ff;
1056 	return ret;
1057 
1058     fail:
1059 	if (bfd >= 0)
1060 		close(bfd);
1061 	if (err_exit)
1062 		exit(1);
1063 	return 0;
1064 }
1065 
1066 static void
1067 init_sector0(int zappart)
1068 {
1069 	int i;
1070 	int copy_size = offsetof(struct mbr_sector, mbr_dsn);
1071 
1072 #ifdef DEFAULT_BOOTCODE
1073 	if (bootsize == 0)
1074 		bootsize = read_boot(DEFAULT_BOOTCODE, bootcode,
1075 			sizeof bootcode, 0);
1076 #endif
1077 #ifdef BOOTSEL
1078 	if (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC
1079 	    && bootcode[0].mbr_bootsel_magic == LE_MBR_BS_MAGIC)
1080 		copy_size = MBR_BS_OFFSET;
1081 #endif
1082 
1083 	if (bootsize != 0) {
1084 		boot_installed = 1;
1085 		memcpy(&mboot, bootcode, copy_size);
1086 		mboot.mbr_bootsel_magic = bootcode[0].mbr_bootsel_magic;
1087 	}
1088 	mboot.mbr_magic = LE_MBR_MAGIC;
1089 
1090 	if (!zappart)
1091 		return;
1092 	for (i = 0; i < MBR_PART_COUNT; i++)
1093 		memset(&mboot.mbr_parts[i], 0, sizeof(mboot.mbr_parts[i]));
1094 }
1095 
1096 static void
1097 get_extended_ptn(void)
1098 {
1099 	struct mbr_partition *mp;
1100 	struct mbr_sector *boot;
1101 	daddr_t offset;
1102 	struct mbr_sector *nptn;
1103 
1104 	/* find first (there should only be one) extended partition */
1105 	for (mp = mboot.mbr_parts; !MBR_IS_EXTENDED(mp->mbrp_type); mp++)
1106 		if (mp >= &mboot.mbr_parts[MBR_PART_COUNT])
1107 			return;
1108 
1109 	/*
1110 	 * The extended partition should be structured as a linked list
1111 	 * (even though it appears, at first glance, to be a tree).
1112 	 */
1113 	ext.base = le32toh(mp->mbrp_start);
1114 	ext.limit = ext.base + le32toh(mp->mbrp_size);
1115 	ext.ptn_id = mp - mboot.mbr_parts;
1116 	for (offset = 0;; offset = le32toh(boot->mbr_parts[1].mbrp_start)) {
1117 		nptn = realloc(ext.ptn, (ext.num_ptn + 1) * sizeof *ext.ptn);
1118 		if (nptn == NULL)
1119 			err(1, "Malloc failed");
1120 		ext.ptn = nptn;
1121 		boot = ext.ptn + ext.num_ptn;
1122 		if (read_s0(offset + ext.base, boot) == -1)
1123 			break;
1124 		/* expect p0 to be valid and p1 to be another extended ptn */
1125 		if (MBR_IS_EXTENDED(boot->mbr_parts[0].mbrp_type))
1126 			break;
1127 		if (boot->mbr_parts[1].mbrp_type != 0 &&
1128 		    !MBR_IS_EXTENDED(boot->mbr_parts[1].mbrp_type))
1129 			break;
1130 		/* p2 and p3 should be unallocated */
1131 		if (boot->mbr_parts[2].mbrp_type != 0 ||
1132 		    boot->mbr_parts[3].mbrp_type != 0)
1133 			break;
1134 		/* data ptn inside extended one */
1135 		if (boot->mbr_parts[0].mbrp_type != 0 &&
1136 		    offset + le32toh(boot->mbr_parts[0].mbrp_start)
1137 		    + le32toh(boot->mbr_parts[0].mbrp_size) > ext.limit)
1138 			break;
1139 
1140 		ext.num_ptn++;
1141 
1142 		if (boot->mbr_parts[1].mbrp_type == 0)
1143 			/* end of extended partition chain */
1144 			return;
1145 		/* must be in sector order */
1146 		if (offset >= le32toh(boot->mbr_parts[1].mbrp_start))
1147 			break;
1148 	}
1149 
1150 	warnx("Extended partition table is corrupt\n");
1151 	ext.is_corrupt = 1;
1152 	ext.num_ptn = 0;
1153 }
1154 
1155 #if defined(USE_DISKLIST)
1156 static void
1157 get_diskname(const char *fullname, char *diskname, size_t size)
1158 {
1159 	const char *p, *p2;
1160 	size_t len;
1161 
1162 	p = strrchr(fullname, '/');
1163 	if (p == NULL)
1164 		p = fullname;
1165 	else
1166 		p++;
1167 
1168 	if (*p == 0) {
1169 		strlcpy(diskname, fullname, size);
1170 		return;
1171 	}
1172 
1173 	if (*p == 'r')
1174 		p++;
1175 
1176 	for (p2 = p; *p2 != 0; p2++)
1177 		if (isdigit((unsigned char)*p2))
1178 			break;
1179 	if (*p2 == 0) {
1180 		/* XXX invalid diskname? */
1181 		strlcpy(diskname, fullname, size);
1182 		return;
1183 	}
1184 	while (isdigit((unsigned char)*p2))
1185 		p2++;
1186 
1187 	len = p2 - p;
1188 	if (len > size) {
1189 		/* XXX */
1190 		strlcpy(diskname, fullname, size);
1191 		return;
1192 	}
1193 
1194 	memcpy(diskname, p, len);
1195 	diskname[len] = 0;
1196 }
1197 #endif
1198 
1199 static void
1200 get_ptn_alignmemt(void)
1201 {
1202 	struct mbr_partition *partp = &mboot.mbr_parts[0];
1203 	uint32_t ptn_0_base, ptn_0_limit;
1204 
1205 	/* Default to using 'traditional' cylinder alignment */
1206 	ptn_alignment = dos_cylindersectors;
1207 	ptn_0_offset = dos_sectors;
1208 
1209 	if (partp->mbrp_type != 0) {
1210 		/* Try to copy alignment of first partition */
1211 		ptn_0_base = le32toh(partp->mbrp_start);
1212 		ptn_0_limit = ptn_0_base + le32toh(partp->mbrp_size);
1213 		if (!(ptn_0_limit & 2047)) {
1214 			/* Partition ends on a 1MB boundary, align to 1MB */
1215 			ptn_alignment = 2048;
1216 			if (ptn_0_base <= 2048
1217 			    && !(ptn_0_base & (ptn_0_base - 1))) {
1218 				/* ptn_base is a power of 2, use it */
1219 				ptn_0_offset = ptn_0_base;
1220 			}
1221 		}
1222 	} else {
1223 		/* Use 1MB alignment for large disks */
1224 		if (disksectors > 2048 * 1024 * 128) {
1225 			ptn_alignment = 2048;
1226 			ptn_0_offset = 2048;
1227 		}
1228 	}
1229 }
1230 
1231 static void
1232 get_bios_geometry(void)
1233 {
1234 #if defined(USE_DISKLIST)
1235 	int mib[2], i;
1236 	size_t len;
1237 	struct biosdisk_info *bip;
1238 	struct nativedisk_info *nip;
1239 	char diskname[8];
1240 
1241 	mib[0] = CTL_MACHDEP;
1242 	mib[1] = CPU_DISKINFO;
1243 	if (sysctl(mib, 2, NULL, &len, NULL, 0) < 0) {
1244 		goto out;
1245 	}
1246 	dl = (struct disklist *) malloc(len);
1247 	if (dl == NULL)
1248 		err(1, "Malloc failed");
1249 	if (sysctl(mib, 2, dl, &len, NULL, 0) < 0) {
1250 		free(dl);
1251 		dl = 0;
1252 		goto out;
1253 	}
1254 
1255 	get_diskname(disk, diskname, sizeof diskname);
1256 
1257 	for (i = 0; i < dl->dl_nnativedisks; i++) {
1258 		nip = &dl->dl_nativedisks[i];
1259 		if (strcmp(diskname, nip->ni_devname))
1260 			continue;
1261 		/*
1262 		 * XXX listing possible matches is better. This is ok for
1263 		 * now because the user has a chance to change it later.
1264 		 * Also, if all the disks have the same parameters then we can
1265 		 * just use them, we don't need to know which disk is which.
1266 		 */
1267 		if (nip->ni_nmatches != 0) {
1268 			bip = &dl->dl_biosdisks[nip->ni_biosmatches[0]];
1269 			dos_cylinders = bip->bi_cyl;
1270 			dos_heads = bip->bi_head;
1271 			dos_sectors = bip->bi_sec;
1272 			if (bip->bi_lbasecs)
1273 				dos_disksectors = bip->bi_lbasecs;
1274 			return;
1275 		}
1276 	}
1277  out:
1278 #endif
1279 	/* Allright, allright, make a stupid guess.. */
1280 	intuit_translated_geometry();
1281 }
1282 
1283 #ifdef BOOTSEL
1284 static daddr_t
1285 get_default_boot(void)
1286 {
1287 	unsigned int id;
1288 	int p;
1289 
1290 	if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1291 		/* default to first active partition */
1292 		return DEFAULT_ACTIVE;
1293 
1294 	id = mboot.mbr_bootsel.mbrbs_defkey;
1295 
1296 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ASCII) {
1297 		/* Keycode is ascii */
1298 		if (id == '\r')
1299 		    return DEFAULT_ACTIVE;
1300 		/* '1'+ => allocated partition id, 'a'+ => disk 0+ */
1301 		if (id >= 'a' && id < 'a' + MAX_BIOS_DISKS)
1302 			return DEFAULT_DISK(id - 'a');
1303 		id -= '1';
1304 	} else {
1305 		/* keycode is PS/2 keycode */
1306 		if (id == SCAN_ENTER)
1307 			return DEFAULT_ACTIVE;
1308 		/* 1+ => allocated partition id, F1+ => disk 0+ */
1309 		if (id >= SCAN_F1 && id < SCAN_F1 + MAX_BIOS_DISKS)
1310 			return DEFAULT_DISK(id - SCAN_F1);
1311 		id -= SCAN_1;
1312 	}
1313 
1314 	/* Convert partition index to the invariant start sector number */
1315 
1316 	for (p = 0; p < MBR_PART_COUNT; p++) {
1317 		if (mboot.mbr_parts[p].mbrp_type == 0)
1318 			continue;
1319 		if (mboot.mbr_bootsel.mbrbs_nametab[p][0] == 0)
1320 			continue;
1321 		if (id-- == 0)
1322 			return le32toh(mboot.mbr_parts[p].mbrp_start);
1323 	}
1324 
1325 	for (p = 0; p < ext.num_ptn; p++) {
1326 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1327 			continue;
1328 		if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1329 			continue;
1330 		if (id-- == 0)
1331 			return ext_offset(p)
1332 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start);
1333 	}
1334 
1335 	return DEFAULT_ACTIVE;
1336 }
1337 
1338 static void
1339 set_default_boot(daddr_t default_ptn)
1340 {
1341 	int p;
1342 	static const unsigned char key_list[] = { SCAN_ENTER, SCAN_F1, SCAN_1,
1343 						'\r', 'a', '1' };
1344 	const unsigned char *key = key_list;
1345 
1346 	if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1347 		/* sanity */
1348 		return;
1349 
1350 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ASCII)
1351 		/* Use ascii values */
1352 		key += 3;
1353 
1354 	if (default_ptn == DEFAULT_ACTIVE) {
1355 		mboot.mbr_bootsel.mbrbs_defkey = key[0];
1356 		return;
1357 	}
1358 
1359 	if (default_ptn >= DEFAULT_DISK(0)
1360 	    && default_ptn < DEFAULT_DISK(MAX_BIOS_DISKS)) {
1361 		mboot.mbr_bootsel.mbrbs_defkey = key[1]
1362 		    + default_ptn - DEFAULT_DISK(0);
1363 		return;
1364 	}
1365 
1366 	mboot.mbr_bootsel.mbrbs_defkey = key[2];
1367 	for (p = 0; p < MBR_PART_COUNT; p++) {
1368 		if (mboot.mbr_parts[p].mbrp_type == 0)
1369 			continue;
1370 		if (mboot.mbr_bootsel.mbrbs_nametab[p][0] == 0)
1371 			continue;
1372 		if (le32toh(mboot.mbr_parts[p].mbrp_start) == default_ptn)
1373 			return;
1374 		mboot.mbr_bootsel.mbrbs_defkey++;
1375 	}
1376 
1377 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_EXTLBA) {
1378 		for (p = 0; p < ext.num_ptn; p++) {
1379 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1380 				continue;
1381 			if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1382 				continue;
1383 			if (le32toh(ext.ptn[p].mbr_parts[0].mbrp_start) +
1384 			    ext_offset(p) == default_ptn)
1385 				return;
1386 			mboot.mbr_bootsel.mbrbs_defkey++;
1387 		}
1388 	}
1389 
1390 	/* Default to first active partition */
1391 	mboot.mbr_bootsel.mbrbs_defkey = key[0];
1392 }
1393 
1394 static void
1395 install_bootsel(int needed)
1396 {
1397 	struct mbr_bootsel *mbs = &mboot.mbr_bootsel;
1398 	int p;
1399 	int ext13 = 0;
1400 	const char *code;
1401 
1402 	needed |= MBR_BS_NEWMBR;	/* need new bootsel code */
1403 
1404 	/* Work out which boot code we need for this configuration */
1405 	for (p = 0; p < MBR_PART_COUNT; p++) {
1406 		if (mboot.mbr_parts[p].mbrp_type == 0)
1407 			continue;
1408 		if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1409 			break;
1410 		if (mbs->mbrbs_nametab[p][0] == 0)
1411 			continue;
1412 		needed |= MBR_BS_ACTIVE;
1413 		if (le32toh(mboot.mbr_parts[p].mbrp_start) >= dos_totalsectors)
1414 			ext13 = MBR_BS_EXTINT13;
1415 	}
1416 
1417 	for (p = 0; p < ext.num_ptn; p++) {
1418 		if (ext.ptn[p].mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1419 			continue;
1420 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1421 			continue;
1422 		if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[p][0] == 0)
1423 			continue;
1424 		needed |= MBR_BS_EXTLBA | MBR_BS_ACTIVE;
1425 	}
1426 
1427 	if (B_flag)
1428 		needed |= MBR_BS_ACTIVE;
1429 
1430 	/* Is the installed code good enough ? */
1431 	if (!i_flag && (needed == 0 ||
1432 	    (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC
1433 	    && (mbs->mbrbs_flags & needed) == needed))) {
1434 		/* yes - just set flags */
1435 		mbs->mbrbs_flags |= ext13;
1436 		return;
1437 	}
1438 
1439 	/* ok - we need to replace the bootcode */
1440 
1441 	if (f_flag && !(i_flag || B_flag)) {
1442 		warnx("Installed bootfile doesn't support required options.");
1443 		return;
1444 	}
1445 
1446 	if (!f_flag && bootsize == 0 && !i_flag)
1447 		/* Output an explanation for the 'update bootcode' prompt. */
1448 		printf("\n%s\n",
1449 		    "Installed bootfile doesn't support required options.");
1450 
1451 	/* Were we told a specific file ? (which we have already read) */
1452 	/* If so check that it supports what we need. */
1453 	if (bootsize != 0 && needed != 0
1454 	    && (bootcode[0].mbr_bootsel_magic != LE_MBR_BS_MAGIC
1455 	    || ((bootcode[0].mbr_bootsel.mbrbs_flags & needed) != needed))) {
1456 		/* No it doesn't... */
1457 		if (f_flag)
1458 			warnx("Bootfile %s doesn't support "
1459 				    "required bootsel options", boot_path );
1460 			/* But install it anyway */
1461 		else
1462 			if (yesno("Bootfile %s doesn't support the required "
1463 			    "options,\ninstall default bootfile instead?",
1464 			    boot_path))
1465 				bootsize = 0;
1466 	}
1467 
1468 	if (bootsize == 0) {
1469 		/* Get name of bootfile that supports the required facilities */
1470 		code = DEFAULT_BOOTCODE;
1471 		if (needed & MBR_BS_ACTIVE)
1472 			code = DEFAULT_BOOTSELCODE;
1473 #ifdef DEFAULT_BOOTEXTCODE
1474 		if (needed & MBR_BS_EXTLBA)
1475 			code = DEFAULT_BOOTEXTCODE;
1476 #endif
1477 
1478 		bootsize = read_boot(code, bootcode, sizeof bootcode, 0);
1479 		if (bootsize == 0)
1480 			/* The old bootcode is better than no bootcode at all */
1481 			return;
1482 		if ((bootcode[0].mbr_bootsel.mbrbs_flags & needed) != needed)
1483 			warnx("Default bootfile %s doesn't support required "
1484 				"options.  Got flags 0x%x, wanted 0x%x\n",
1485 				boot_path, bootcode[0].mbr_bootsel.mbrbs_flags,
1486 				needed);
1487 	}
1488 
1489 	if (!f_flag && !yesno("Update the bootcode from %s?", boot_path))
1490 		return;
1491 
1492 	init_sector0(0);
1493 
1494 	if (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC)
1495 		mbs->mbrbs_flags = bootcode[0].mbr_bootsel.mbrbs_flags | ext13;
1496 }
1497 
1498 static daddr_t
1499 configure_bootsel(daddr_t default_ptn)
1500 {
1501 	struct mbr_bootsel *mbs = &mboot.mbr_bootsel;
1502 	int i, item, opt;
1503 	int tmo;
1504 	daddr_t *off;
1505 	int num_bios_disks;
1506 
1507 #if defined(USE_DISKLIST)
1508 	if (dl != NULL) {
1509 		num_bios_disks = dl->dl_nbiosdisks;
1510 		if (num_bios_disks > MAX_BIOS_DISKS)
1511 			num_bios_disks = MAX_BIOS_DISKS;
1512 	} else
1513 #endif
1514 		num_bios_disks = MAX_BIOS_DISKS;
1515 
1516 	printf("\nBoot selector configuration:\n");
1517 
1518 	/* The timeout value is in ticks, ~18.2 Hz. Avoid using floats.
1519 	 * Ticks are nearly 64k/3600 - so our long timers are sligtly out!
1520 	 * Newer bootcode always waits for 1 tick, so treats 0xffff
1521 	 * as wait forever.
1522 	 */
1523 	tmo = le16toh(mbs->mbrbs_timeo);
1524 	tmo = tmo == 0xffff ? -1 : (10 * tmo + 9) / 182;
1525 	tmo = decimal("Timeout value (0 to 3600 seconds, -1 => never)",
1526 			tmo, 0, -1, 3600);
1527 	mbs->mbrbs_timeo = htole16(tmo == -1 ? 0xffff : (tmo * 182) / 10);
1528 
1529 	off = calloc(1 + MBR_PART_COUNT + ext.num_ptn + num_bios_disks, sizeof *off);
1530 	if (off == NULL)
1531 		err(1, "Malloc failed");
1532 
1533 	printf("Select the default boot option. Options are:\n\n");
1534 	item = 0;
1535 	opt = 0;
1536 	off[opt] = DEFAULT_ACTIVE;
1537 	printf("%d: The first active partition\n", opt);
1538 	for (i = 0; i < MBR_PART_COUNT; i++) {
1539 		if (mboot.mbr_parts[i].mbrp_type == 0)
1540 			continue;
1541 		if (mbs->mbrbs_nametab[i][0] == 0)
1542 			continue;
1543 		printf("%d: %s\n", ++opt, &mbs->mbrbs_nametab[i][0]);
1544 		off[opt] = le32toh(mboot.mbr_parts[i].mbrp_start);
1545 		if (off[opt] == default_ptn)
1546 			item = opt;
1547 	}
1548 	if (mbs->mbrbs_flags & MBR_BS_EXTLBA) {
1549 		for (i = 0; i < ext.num_ptn; i++) {
1550 			if (ext.ptn[i].mbr_parts[0].mbrp_type == 0)
1551 				continue;
1552 			if (ext.ptn[i].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1553 				continue;
1554 			printf("%d: %s\n",
1555 			    ++opt, ext.ptn[i].mbr_bootsel.mbrbs_nametab[0]);
1556 			off[opt] = ext_offset(i) +
1557 			    le32toh(ext.ptn[i].mbr_parts[0].mbrp_start);
1558 			if (off[opt] == default_ptn)
1559 				item = opt;
1560 		}
1561 	}
1562 	for (i = 0; i < num_bios_disks; i++) {
1563 		printf("%d: Harddisk %d\n", ++opt, i);
1564 		off[opt] = DEFAULT_DISK(i);
1565 		if (DEFAULT_DISK(i) == default_ptn)
1566 			item = opt;
1567 	}
1568 
1569 	item = decimal("Default boot option", item, 0, 0, opt);
1570 
1571 	default_ptn = off[item];
1572 	free(off);
1573 	return default_ptn;
1574 }
1575 #endif /* BOOTSEL */
1576 
1577 
1578 /* Prerequisite: the disklabel parameters and master boot record must
1579  *		 have been read (i.e. dos_* and mboot are meaningful).
1580  * Specification: modifies dos_cylinders, dos_heads, dos_sectors, and
1581  *		  dos_cylindersectors to be consistent with what the
1582  *		  partition table is using, if we can find a geometry
1583  *		  which is consistent with all partition table entries.
1584  *		  We may get the number of cylinders slightly wrong (in
1585  *		  the conservative direction).  The idea is to be able
1586  *		  to create a NetBSD partition on a disk we don't know
1587  *		  the translated geometry of.
1588  * This routine is only used for non-x86 systems or when we fail to
1589  * get the BIOS geometry from the kernel.
1590  */
1591 static void
1592 intuit_translated_geometry(void)
1593 {
1594 	uint32_t xcylinders;
1595 	int xheads = -1, xsectors = -1, i, j;
1596 	unsigned int c1, h1, s1, c2, h2, s2;
1597 	unsigned long a1, a2;
1598 	uint64_t num, denom;
1599 
1600 	/*
1601 	 * The physical parameters may be invalid as bios geometry.
1602 	 * If we cannot determine the actual bios geometry, we are
1603 	 * better off picking a likely 'faked' geometry than leaving
1604 	 * the invalid physical one.
1605 	 */
1606 
1607 	if (dos_cylinders > MAXCYL || dos_heads > MAXHEAD ||
1608 	    dos_sectors > MAXSECTOR) {
1609 		h1 = MAXHEAD - 1;
1610 		c1 = MAXCYL - 1;
1611 #if defined(USE_DISKLIST)
1612 		if (dl != NULL) {
1613 			/* BIOS may use 256 heads or 1024 cylinders */
1614 			for (i = 0; i < dl->dl_nbiosdisks; i++) {
1615 				if (h1 < (unsigned int)dl->dl_biosdisks[i].bi_head)
1616 					h1 = dl->dl_biosdisks[i].bi_head;
1617 				if (c1 < (unsigned int)dl->dl_biosdisks[i].bi_cyl)
1618 					c1 = dl->dl_biosdisks[i].bi_cyl;
1619 			}
1620 		}
1621 #endif
1622 		dos_sectors = MAXSECTOR;
1623 		dos_heads = h1;
1624 		dos_cylinders = disklabel.d_secperunit / (MAXSECTOR * h1);
1625 		if (dos_cylinders > c1)
1626 			dos_cylinders = c1;
1627 	}
1628 
1629 	/* Try to deduce the number of heads from two different mappings. */
1630 	for (i = 0; i < MBR_PART_COUNT * 2 - 1; i++) {
1631 		if (get_mapping(i, &c1, &h1, &s1, &a1) < 0)
1632 			continue;
1633 		a1 -= s1;
1634 		for (j = i + 1; j < MBR_PART_COUNT * 2; j++) {
1635 			if (get_mapping(j, &c2, &h2, &s2, &a2) < 0)
1636 				continue;
1637 			a2 -= s2;
1638 			num = (uint64_t)h1 * a2 - (uint64_t)h2 * a1;
1639 			denom = (uint64_t)c2 * a1 - (uint64_t)c1 * a2;
1640 			if (denom != 0 && num != 0 && num % denom == 0) {
1641 				xheads = num / denom;
1642 				xsectors = a1 / (c1 * xheads + h1);
1643 				break;
1644 			}
1645 		}
1646 		if (xheads != -1)
1647 			break;
1648 	}
1649 
1650 	if (xheads == -1) {
1651 		if (F_flag)
1652 			return;
1653 		warnx("Cannot determine the number of heads");
1654 		return;
1655 	}
1656 
1657 	if (xsectors == -1) {
1658 		warnx("Cannot determine the number of sectors");
1659 		return;
1660 	}
1661 
1662 	/* Estimate the number of cylinders. */
1663 	xcylinders = disklabel.d_secperunit / xheads / xsectors;
1664 	if (disklabel.d_secperunit > xcylinders * xheads * xsectors)
1665 		xcylinders++;
1666 
1667 	/*
1668 	 * Now verify consistency with each of the partition table entries.
1669 	 * Be willing to shove cylinders up a little bit to make things work,
1670 	 * but translation mismatches are fatal.
1671 	 */
1672 	for (i = 0; i < MBR_PART_COUNT * 2; i++) {
1673 		if (get_mapping(i, &c1, &h1, &s1, &a1) < 0)
1674 			continue;
1675 		if (c1 >= MAXCYL - 2)
1676 			continue;
1677 		if (xsectors * (c1 * xheads + h1) + s1 != a1)
1678 			return;
1679 	}
1680 
1681 
1682 	/* Everything checks out.
1683 	 * Reset the geometry to use for further calculations.
1684 	 * But cylinders cannot be > 1024.
1685 	 */
1686 	if (xcylinders > MAXCYL)
1687 		dos_cylinders = MAXCYL;
1688 	else
1689 		dos_cylinders = xcylinders;
1690 	dos_heads = xheads;
1691 	dos_sectors = xsectors;
1692 }
1693 
1694 /*
1695  * For the purposes of intuit_translated_geometry(), treat the partition
1696  * table as a list of eight mapping between (cylinder, head, sector)
1697  * triplets and absolute sectors.  Get the relevant geometry triplet and
1698  * absolute sectors for a given entry, or return -1 if it isn't present.
1699  * Note: for simplicity, the returned sector is 0-based.
1700  */
1701 static int
1702 get_mapping(int i, unsigned int *cylinder, unsigned int *head, unsigned int *sector,
1703     unsigned long *absolute)
1704 {
1705 	struct mbr_partition *part = &mboot.mbr_parts[i / 2];
1706 
1707 	if (part->mbrp_type == 0)
1708 		return -1;
1709 	if (i % 2 == 0) {
1710 		*cylinder = MBR_PCYL(part->mbrp_scyl, part->mbrp_ssect);
1711 		*head = part->mbrp_shd;
1712 		*sector = MBR_PSECT(part->mbrp_ssect);
1713 		*absolute = le32toh(part->mbrp_start);
1714 	} else {
1715 		*cylinder = MBR_PCYL(part->mbrp_ecyl, part->mbrp_esect);
1716 		*head = part->mbrp_ehd;
1717 		*sector = MBR_PSECT(part->mbrp_esect);
1718 		*absolute = le32toh(part->mbrp_start)
1719 		    + le32toh(part->mbrp_size) - 1;
1720 	}
1721 	/* Sanity check the data against all zeroes */
1722 	if ((*cylinder == 0) && (*sector == 0) && (*head == 0))
1723 		return -1;
1724 	/* sector numbers in the MBR partition table start at 1 */
1725 	*sector = *sector - 1;
1726 	/* Sanity check the data against max values */
1727 	if ((((*cylinder * MAXHEAD) + *head) * MAXSECTOR + *sector) < *absolute)
1728 		/* cannot be a CHS mapping */
1729 		return -1;
1730 	return 0;
1731 }
1732 
1733 static void
1734 delete_ptn(int part)
1735 {
1736 	if (part == ext.ptn_id) {
1737 		/* forget all about the extended partition */
1738 		free(ext.ptn);
1739 		memset(&ext, 0, sizeof ext);
1740 	}
1741 
1742 	mboot.mbr_parts[part].mbrp_type = 0;
1743 }
1744 
1745 static void
1746 delete_ext_ptn(int part)
1747 {
1748 
1749 	if (part == 0) {
1750 		ext.ptn[0].mbr_parts[0].mbrp_type = 0;
1751 		return;
1752 	}
1753 	ext.ptn[part - 1].mbr_parts[1] = ext.ptn[part].mbr_parts[1];
1754 	memmove(&ext.ptn[part], &ext.ptn[part + 1],
1755 		(ext.num_ptn - part - 1) * sizeof ext.ptn[0]);
1756 	ext.num_ptn--;
1757 }
1758 
1759 static int
1760 add_ext_ptn(daddr_t start, daddr_t size)
1761 {
1762 	int part;
1763 	struct mbr_partition *partp;
1764 	struct mbr_sector *nptn;
1765 
1766 	nptn = realloc(ext.ptn, (ext.num_ptn + 1) * sizeof *ext.ptn);
1767 	if (!nptn)
1768 		err(1, "realloc");
1769 	ext.ptn = nptn;
1770 	for (part = 0; part < ext.num_ptn; part++)
1771 		if (ext_offset(part) > start)
1772 			break;
1773 	/* insert before 'part' - make space... */
1774 	memmove(&ext.ptn[part + 1], &ext.ptn[part],
1775 		(ext.num_ptn - part) * sizeof ext.ptn[0]);
1776 	memset(&ext.ptn[part], 0, sizeof ext.ptn[0]);
1777 	ext.ptn[part].mbr_magic = LE_MBR_MAGIC;
1778 	/* we will be 'part' */
1779 	if (part == 0) {
1780 		/* link us to 'next' */
1781 		partp = &ext.ptn[0].mbr_parts[1];
1782 		/* offset will be fixed by caller */
1783 		partp->mbrp_size = htole32(
1784 		    le32toh(ext.ptn[1].mbr_parts[0].mbrp_start) +
1785 		    le32toh(ext.ptn[1].mbr_parts[0].mbrp_size));
1786 	} else {
1787 		/* link us to prev's next */
1788 		partp = &ext.ptn[part - 1].mbr_parts[1];
1789 		ext.ptn[part].mbr_parts[1] = *partp;
1790 		/* and prev onto us */
1791 		partp->mbrp_start = htole32(start - ptn_0_offset - ext.base);
1792 		partp->mbrp_size = htole32(size + ptn_0_offset);
1793 	}
1794 	partp->mbrp_type = 5;	/* as used by win98 */
1795 	partp->mbrp_flag = 0;
1796 	/* wallop in some CHS values - win98 doesn't saturate them */
1797 	dos(le32toh(partp->mbrp_start),
1798 	    &partp->mbrp_scyl, &partp->mbrp_shd, &partp->mbrp_ssect);
1799 	dos(le32toh(partp->mbrp_start) + le32toh(partp->mbrp_size) - 1,
1800 	    &partp->mbrp_ecyl, &partp->mbrp_ehd, &partp->mbrp_esect);
1801 	ext.num_ptn++;
1802 
1803 	return part;
1804 }
1805 
1806 static const char *
1807 check_overlap(int part, int sysid, daddr_t start, daddr_t size, int fix)
1808 {
1809 	int p;
1810 	unsigned int p_s, p_e;
1811 
1812 	if (sysid != 0) {
1813 		if (start == 0)
1814 			return "Sector zero is reserved for the MBR";
1815 #if 0
1816 		if (start < ptn_0_offset)
1817 			/* This is just a convention, not a requirement */
1818 			return "Track zero is reserved for the BIOS";
1819 #endif
1820 		if (start + size > disksectors)
1821 			return "Partition exceeds size of disk";
1822 		for (p = 0; p < MBR_PART_COUNT; p++) {
1823 			if (p == part || mboot.mbr_parts[p].mbrp_type == 0)
1824 				continue;
1825 			p_s = le32toh(mboot.mbr_parts[p].mbrp_start);
1826 			p_e = p_s + le32toh(mboot.mbr_parts[p].mbrp_size);
1827 			if (start + size <= p_s || start >= p_e)
1828 				continue;
1829 			if (f_flag) {
1830 				if (fix)
1831 					delete_ptn(p);
1832 				return 0;
1833 			}
1834 			return "Overlaps another partition";
1835 		}
1836 	}
1837 
1838 	/* Are we trying to create an extended partition */
1839 	if (!MBR_IS_EXTENDED(mboot.mbr_parts[part].mbrp_type)) {
1840 		/* this wasn't the extended partition */
1841 		if (!MBR_IS_EXTENDED(sysid))
1842 			return 0;
1843 		/* making an extended partition */
1844 		if (ext.base != 0) {
1845 			if (!f_flag)
1846 				return "There cannot be 2 extended partitions";
1847 			if (fix)
1848 				delete_ptn(ext.ptn_id);
1849 		}
1850 		if (fix) {
1851 			/* allocate a new extended partition */
1852 			ext.ptn = calloc(1, sizeof ext.ptn[0]);
1853 			if (ext.ptn == NULL)
1854 				err(1, "Malloc failed");
1855 			ext.ptn[0].mbr_magic = LE_MBR_MAGIC;
1856 			ext.ptn_id = part;
1857 			ext.base = start;
1858 			ext.limit = start + size;
1859 			ext.num_ptn = 1;
1860 		}
1861 		return 0;
1862 	}
1863 
1864 	/* Check we haven't cut space allocated to an extended ptn */
1865 
1866 	if (!MBR_IS_EXTENDED(sysid)) {
1867 		/* no longer an extended partition */
1868 		if (fix) {
1869 			/* Kill all memory of the extended partitions */
1870 			delete_ptn(part);
1871 			return 0;
1872 		}
1873 		if (ext.num_ptn == 0 ||
1874 		    (ext.num_ptn == 1 && ext.ptn[0].mbr_parts[0].mbrp_type == 0))
1875 			/* nothing in extended partition */
1876 			return 0;
1877 		if (f_flag)
1878 			return 0;
1879 		if (yesno("Do you really want to delete all the extended partitions?"))
1880 			return 0;
1881 		return "Extended partition busy";
1882 	}
1883 
1884 	if (le32toh(mboot.mbr_parts[part].mbrp_start) != ext.base)
1885 		/* maybe impossible, but an extra sanity check */
1886 		return 0;
1887 
1888 	for (p = ext.num_ptn; --p >= 0;) {
1889 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1890 			continue;
1891 		p_s = ext_offset(p);
1892 		p_e = p_s + le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
1893 			  + le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
1894 		if (p_s >= start && p_e <= start + size)
1895 			continue;
1896 		if (!f_flag)
1897 			return "Extended partition outside main partition";
1898 		if (fix)
1899 			delete_ext_ptn(p);
1900 	}
1901 
1902 	if (fix && start != ext.base) {
1903 		/* The internal offsets need to be fixed up */
1904 		for (p = 0; p < ext.num_ptn - 1; p++)
1905 			ext.ptn[p].mbr_parts[1].mbrp_start = htole32(
1906 			    le32toh(ext.ptn[p].mbr_parts[1].mbrp_start)
1907 				    + ext.base - start);
1908 		/* and maybe an empty partition at the start */
1909 		if (ext.ptn[0].mbr_parts[0].mbrp_type == 0) {
1910 			if (le32toh(ext.ptn[0].mbr_parts[1].mbrp_start) == 0) {
1911 				/* don't need the empty slot */
1912 				memmove(&ext.ptn[0], &ext.ptn[1],
1913 					(ext.num_ptn - 1) * sizeof ext.ptn[0]);
1914 				ext.num_ptn--;
1915 			}
1916 		} else {
1917 			/* must create an empty slot */
1918 			add_ext_ptn(start, ptn_0_offset);
1919 			ext.ptn[0].mbr_parts[1].mbrp_start = htole32(ext.base
1920 								- start);
1921 		}
1922 	}
1923 	if (fix) {
1924 		ext.base = start;
1925 		ext.limit = start + size;
1926 	}
1927 	return 0;
1928 }
1929 
1930 static const char *
1931 check_ext_overlap(int part, int sysid, daddr_t start, daddr_t size, int fix)
1932 {
1933 	int p;
1934 	unsigned int p_s, p_e;
1935 
1936 	if (sysid == 0)
1937 		return 0;
1938 
1939 	if (MBR_IS_EXTENDED(sysid))
1940 		return "Nested extended partitions are not allowed";
1941 
1942 	/* allow one track at start for extended partition header */
1943 	start -= ptn_0_offset;
1944 	size += ptn_0_offset;
1945 	if (start < ext.base || start + size > ext.limit)
1946 		return "Outside bounds of extended partition";
1947 
1948 	if (f_flag && !fix)
1949 		return 0;
1950 
1951 	for (p = ext.num_ptn; --p >= 0;) {
1952 		if (p == part || ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1953 			continue;
1954 		p_s = ext_offset(p);
1955 		p_e = p_s + le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
1956 			+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
1957 		if (p == 0)
1958 			p_s += le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
1959 							- ptn_0_offset;
1960 		if (start < p_e && start + size > p_s) {
1961 			if (!f_flag)
1962 				return "Overlaps another extended partition";
1963 			if (fix) {
1964 				if (part == -1)
1965 					delete_ext_ptn(p);
1966 				else
1967 					/* must not change numbering yet */
1968 					ext.ptn[p].mbr_parts[0].mbrp_type = 0;
1969 			}
1970 		}
1971 	}
1972 	return 0;
1973 }
1974 
1975 static int
1976 change_part(int extended, int part, int sysid, daddr_t start, daddr_t size,
1977 	char *bootmenu)
1978 {
1979 	struct mbr_partition *partp;
1980 	struct mbr_sector *boot;
1981 	daddr_t offset;
1982 	const char *e;
1983 	int upart = part;
1984 	int p;
1985 	int fl;
1986 	daddr_t n_s, n_e;
1987 	const char *errtext;
1988 #ifdef BOOTSEL
1989 	char tmp_bootmenu[MBR_PART_COUNT * (MBR_BS_PARTNAMESIZE + 1)];
1990 	int bootmenu_len = (extended ? MBR_PART_COUNT : 1) * (MBR_BS_PARTNAMESIZE + 1);
1991 #endif
1992 
1993 	if (extended) {
1994 		if (part != -1 && part < ext.num_ptn) {
1995 			boot = &ext.ptn[part];
1996 			partp = &boot->mbr_parts[0];
1997 			offset = ext_offset(part);
1998 		} else {
1999 			part = -1;
2000 			boot = 0;
2001 			partp = 0;
2002 			offset = 0;
2003 		}
2004 		upart = 0;
2005 		e = "E";
2006 	} else {
2007 		boot = &mboot;
2008 		partp = &boot->mbr_parts[part];
2009 		offset = 0;
2010 		e = "";
2011 	}
2012 
2013 	if (!f_flag && part != -1) {
2014 		printf("The data for partition %s%d is:\n", e, part);
2015 		print_part(boot, upart, offset);
2016 	}
2017 
2018 #ifdef BOOTSEL
2019 	if (bootmenu != NULL)
2020 		strlcpy(tmp_bootmenu, bootmenu, bootmenu_len);
2021 	else
2022 		if (boot != NULL && boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC)
2023 			strlcpy(tmp_bootmenu,
2024 				boot->mbr_bootsel.mbrbs_nametab[upart],
2025 				bootmenu_len);
2026 		else
2027 			tmp_bootmenu[0] = 0;
2028 #endif
2029 
2030 	if (!s_flag && partp != NULL) {
2031 		/* values not specified, default to current ones */
2032 		sysid = partp->mbrp_type;
2033 		start = offset + le32toh(partp->mbrp_start);
2034 		size = le32toh(partp->mbrp_size);
2035 	}
2036 
2037 	/* creating a new partition, default to free space */
2038 	if (!s_flag && sysid == 0 && extended) {
2039 		/* non-extended partition */
2040 		start = ext.base;
2041 		for (p = 0; p < ext.num_ptn; p++) {
2042 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2043 				continue;
2044 			n_s = ext_offset(p);
2045 			if (n_s > start + ptn_0_offset)
2046 				break;
2047 			start = ext_offset(p)
2048 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2049 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
2050 		}
2051 		if (ext.limit - start <= ptn_0_offset) {
2052 			printf("No space in extended partition\n");
2053 			return 0;
2054 		}
2055 		start += ptn_0_offset;
2056 	}
2057 
2058 	if (!s_flag && sysid == 0 && !extended) {
2059 		/* same for non-extended partition */
2060 		/* first see if old start is free */
2061 		if (start < ptn_0_offset)
2062 			start = 0;
2063 		for (p = 0; start != 0 && p < MBR_PART_COUNT; p++) {
2064 			if (mboot.mbr_parts[p].mbrp_type == 0)
2065 				continue;
2066 			n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2067 			if (start >= n_s &&
2068 			    start < n_s + le32toh(mboot.mbr_parts[p].mbrp_size))
2069 				start = 0;
2070 		}
2071 		if (start == 0) {
2072 			/* Look for first gap */
2073 			start = ptn_0_offset;
2074 			for (p = 0; p < MBR_PART_COUNT; p++) {
2075 				if (mboot.mbr_parts[p].mbrp_type == 0)
2076 					continue;
2077 				n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2078 				n_e = n_s + le32toh(mboot.mbr_parts[p].mbrp_size);
2079 				if (start >= n_s && start < n_e) {
2080 					start = n_e;
2081 					p = -1;
2082 				}
2083 			}
2084 			if (start >= disksectors && !I_flag) {
2085 				printf("No free space\n");
2086 				return 0;
2087 			}
2088 		}
2089 	}
2090 
2091 	if (!f_flag) {
2092 		/* request new values from user */
2093 		if (sysid == 0)
2094 			sysid = 169;
2095 		sysid = decimal("sysid", sysid, 0, 0, 255);
2096 		if (sysid == 0 && !v_flag) {
2097 			start = 0;
2098 			size = 0;
2099 #ifdef BOOTSEL
2100 			tmp_bootmenu[0] = 0;
2101 #endif
2102 		} else {
2103 			daddr_t old = start;
2104 			daddr_t lim = extended ? ext.limit : disksectors;
2105 			start = decimal("start", start,
2106 				DEC_SEC | DEC_RND_0 | (extended ? DEC_RND : 0),
2107 				extended ? ext.base : 0, lim);
2108 			/* Adjust 'size' so that end doesn't move when 'start'
2109 			 * is only changed slightly.
2110 			 */
2111 			if (size > start - old)
2112 				size -= start - old;
2113 			else
2114 				size = 0;
2115 			/* Find end of available space from this start point */
2116 			if (extended) {
2117 				for (p = 0; p < ext.num_ptn; p++) {
2118 					if (p == part)
2119 						continue;
2120 					if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2121 						continue;
2122 					n_s = ext_offset(p);
2123 					if (n_s > start && n_s < lim)
2124 						lim = n_s;
2125 					if (start >= n_s && start < n_s
2126 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2127 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size)) {
2128 						lim = start;
2129 						break;
2130 					}
2131 				}
2132 			} else {
2133 				for (p = 0; p < MBR_PART_COUNT; p++) {
2134 					if (p == part)
2135 						continue;
2136 					if (mboot.mbr_parts[p].mbrp_type == 0)
2137 						continue;
2138 					n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2139 					if (n_s > start && n_s < lim)
2140 						lim = n_s;
2141 					if (start >= n_s && start < n_s
2142 				    + le32toh(mboot.mbr_parts[p].mbrp_size)) {
2143 						lim = start;
2144 						break;
2145 					}
2146 				}
2147 			}
2148 			lim -= start;
2149 			if (lim == 0) {
2150 				printf("Start sector already allocated\n");
2151 				return 0;
2152 			}
2153 			if (size == 0 || size > lim)
2154 				size = lim;
2155 			fl = DEC_SEC;
2156 			if (start % ptn_alignment == ptn_0_offset)
2157 				fl |= DEC_RND_DOWN;
2158 			if (start == 2 * ptn_0_offset)
2159 				fl |= DEC_RND_DOWN | DEC_RND_DOWN_2;
2160 			size = decimal("size", size, fl, 0, lim);
2161 #ifdef BOOTSEL
2162 #ifndef DEFAULT_BOOTEXTCODE
2163 			if (!extended)
2164 #endif
2165 				string("bootmenu", bootmenu_len, tmp_bootmenu);
2166 #endif
2167 		}
2168 	}
2169 
2170 	/*
2171 	 * Before we write these away, we must verify that nothing
2172 	 * untoward has been requested.
2173 	 */
2174 
2175 	if (extended)
2176 		errtext = check_ext_overlap(part, sysid, start, size, 0);
2177 	else
2178 		errtext = check_overlap(part, sysid, start, size, 0);
2179 	if (errtext != NULL && !I_flag) {
2180 		if (f_flag)
2181 			errx(2, "%s\n", errtext);
2182 		printf("%s\n", errtext);
2183 		return 0;
2184 	}
2185 
2186 	/*
2187 	 * Before proceeding, delete any overlapped partitions.
2188 	 * This can only happen if '-f' was supplied on the command line.
2189 	 * Just hope the caller knows what they are doing.
2190 	 * This also fixes the base of each extended partition if the
2191 	 * partition itself has moved.
2192 	 */
2193 	if (!I_flag) {
2194 		if (extended)
2195 			errtext = check_ext_overlap(part, sysid, start, size, 1);
2196 		else
2197 			errtext = check_overlap(part, sysid, start, size, 1);
2198 		if (errtext)
2199 			errx(1, "%s\n", errtext);
2200 	}
2201 
2202 
2203 	if (sysid == 0) {
2204 		/* delete this partition - save info though */
2205 		if (partp == NULL)
2206 			/* must have been trying to create an extended ptn */
2207 			return 0;
2208 		if (start == 0 && size == 0)
2209 			memset(partp, 0, sizeof *partp);
2210 #ifdef BOOTSEL
2211 		if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC)
2212 			memset(boot->mbr_bootsel.mbrbs_nametab[upart], 0,
2213 				sizeof boot->mbr_bootsel.mbrbs_nametab[0]);
2214 #endif
2215 		if (extended)
2216 			delete_ext_ptn(part);
2217 		else
2218 			delete_ptn(part);
2219 		return 1;
2220 	}
2221 
2222 
2223 	if (extended) {
2224 		if (part != -1)
2225 			delete_ext_ptn(part);
2226 		if (start == ext.base + ptn_0_offset)
2227 			/* First one must have been free */
2228 			part = 0;
2229 		else
2230 			part = add_ext_ptn(start, size);
2231 
2232 		/* These must be re-calculated because of the realloc */
2233 		boot = &ext.ptn[part];
2234 		partp = &boot->mbr_parts[0];
2235 		offset = ext_offset(part);
2236 	}
2237 
2238 	partp->mbrp_type = sysid;
2239 	partp->mbrp_start = htole32( start - offset);
2240 	partp->mbrp_size = htole32( size);
2241 	dos(start, &partp->mbrp_scyl, &partp->mbrp_shd, &partp->mbrp_ssect);
2242 	dos(start + size - 1,
2243 		    &partp->mbrp_ecyl, &partp->mbrp_ehd, &partp->mbrp_esect);
2244 #ifdef BOOTSEL
2245 	if (extended) {
2246 		boot->mbr_bootsel_magic = LE_MBR_BS_MAGIC;
2247 		strncpy(boot->mbr_bootsel.mbrbs_nametab[upart], tmp_bootmenu,
2248 			bootmenu_len);
2249 	} else {
2250 		/* We need to bootselect code installed in order to have
2251 		 * somewhere to safely write the menu tag.
2252 		 */
2253 		if (boot->mbr_bootsel_magic != LE_MBR_BS_MAGIC) {
2254 			if (f_flag ||
2255 			    yesno("The bootselect code is not installed, "
2256 				"do you want to install it now?"))
2257 				install_bootsel(MBR_BS_ACTIVE);
2258 		}
2259 		if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
2260 			strncpy(boot->mbr_bootsel.mbrbs_nametab[upart],
2261 				tmp_bootmenu, bootmenu_len);
2262 		}
2263 	}
2264 #endif
2265 
2266 	if (v_flag && !f_flag && yesno("Explicitly specify beg/end address?")) {
2267 		/* this really isn't a good idea.... */
2268 		int tsector, tcylinder, thead;
2269 
2270 		tcylinder = MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect);
2271 		thead = partp->mbrp_shd;
2272 		tsector = MBR_PSECT(partp->mbrp_ssect);
2273 		tcylinder = decimal("beginning cylinder",
2274 				tcylinder, 0, 0, dos_cylinders - 1);
2275 		thead = decimal("beginning head",
2276 				thead, 0, 0, dos_heads - 1);
2277 		tsector = decimal("beginning sector",
2278 				tsector, 0, 1, dos_sectors);
2279 		partp->mbrp_scyl = DOSCYL(tcylinder);
2280 		partp->mbrp_shd = thead;
2281 		partp->mbrp_ssect = DOSSECT(tsector, tcylinder);
2282 
2283 		tcylinder = MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect);
2284 		thead = partp->mbrp_ehd;
2285 		tsector = MBR_PSECT(partp->mbrp_esect);
2286 		tcylinder = decimal("ending cylinder",
2287 				tcylinder, 0, 0, dos_cylinders - 1);
2288 		thead = decimal("ending head",
2289 				thead, 0, 0, dos_heads - 1);
2290 		tsector = decimal("ending sector",
2291 				tsector, 0, 1, dos_sectors);
2292 		partp->mbrp_ecyl = DOSCYL(tcylinder);
2293 		partp->mbrp_ehd = thead;
2294 		partp->mbrp_esect = DOSSECT(tsector, tcylinder);
2295 	}
2296 
2297 	/* If we had to mark an extended partition as deleted because
2298 	 * another request would have overlapped it, now is the time
2299 	 * to do the actual delete.
2300 	 */
2301 	if (extended && f_flag) {
2302 		for (p = ext.num_ptn; --p >= 0;)
2303 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2304 				delete_ext_ptn(p);
2305 	}
2306 	return 1;
2307 }
2308 
2309 static void
2310 print_geometry(void)
2311 {
2312 
2313 	if (sh_flag) {
2314 		printf("DISK=%s\n", disk);
2315 		printf("DLCYL=%d\nDLHEAD=%d\nDLSEC=%d\nDLSIZE=%"PRIdaddr"\n",
2316 			cylinders, heads, sectors, disksectors);
2317 		printf("BCYL=%d\nBHEAD=%d\nBSEC=%d\nBDLSIZE=%"PRIdaddr"\n",
2318 			dos_cylinders, dos_heads, dos_sectors, dos_disksectors);
2319 		printf("NUMEXTPTN=%d\n", ext.num_ptn);
2320 		return;
2321 	}
2322 
2323 	/* Not sh_flag */
2324 	printf("Disk: %s\n", disk);
2325 	printf("NetBSD disklabel disk geometry:\n");
2326 	printf("cylinders: %d, heads: %d, sectors/track: %d "
2327 	    "(%d sectors/cylinder)\ntotal sectors: %"PRIdaddr", "
2328 	    "bytes/sector: %zd\n\n", cylinders, heads, sectors,
2329 	    cylindersectors, disksectors, secsize);
2330 	printf("BIOS disk geometry:\n");
2331 	printf("cylinders: %d, heads: %d, sectors/track: %d "
2332 	    "(%d sectors/cylinder)\ntotal sectors: %"PRIdaddr"\n\n",
2333 	    dos_cylinders, dos_heads, dos_sectors, dos_cylindersectors,
2334 	    dos_disksectors);
2335 	printf("Partitions aligned to %d sector boundaries, offset %d\n\n",
2336 	    ptn_alignment, ptn_0_offset);
2337 }
2338 
2339 /* Find the first active partition, else return MBR_PART_COUNT */
2340 static int
2341 first_active(void)
2342 {
2343 	struct mbr_partition *partp = &mboot.mbr_parts[0];
2344 	int part;
2345 
2346 	for (part = 0; part < MBR_PART_COUNT; part++)
2347 		if (partp[part].mbrp_flag & MBR_PFLAG_ACTIVE)
2348 			return part;
2349 	return MBR_PART_COUNT;
2350 }
2351 
2352 static void
2353 change_active(int which)
2354 {
2355 	struct mbr_partition *partp;
2356 	int part;
2357 	int active = MBR_PART_COUNT;
2358 
2359 	partp = &mboot.mbr_parts[0];
2360 
2361 	if (a_flag && which != -1)
2362 		active = which;
2363 	else
2364 		active = first_active();
2365 	if (!f_flag) {
2366 		if (yesno("Do you want to change the active partition?")) {
2367 			printf ("Choosing %d will make no partition active.\n",
2368 			    MBR_PART_COUNT);
2369 			do {
2370 				active = decimal("active partition",
2371 						active, 0, 0, MBR_PART_COUNT);
2372 			} while (!yesno("Are you happy with this choice?"));
2373 		} else
2374 			return;
2375 	} else
2376 		if (active != MBR_PART_COUNT)
2377 			printf ("Making partition %d active.\n", active);
2378 
2379 	for (part = 0; part < MBR_PART_COUNT; part++)
2380 		partp[part].mbrp_flag &= ~MBR_PFLAG_ACTIVE;
2381 	if (active < MBR_PART_COUNT)
2382 		partp[active].mbrp_flag |= MBR_PFLAG_ACTIVE;
2383 }
2384 
2385 static void
2386 change_bios_geometry(void)
2387 {
2388 	print_geometry();
2389 	if (!yesno("Do you want to change our idea of what BIOS thinks?"))
2390 		return;
2391 
2392 #if defined(USE_DISKLIST)
2393 	if (dl != NULL) {
2394 		struct biosdisk_info *bip;
2395 		int i;
2396 
2397 		for (i = 0; i < dl->dl_nbiosdisks; i++) {
2398 			if (i == 0)
2399 				printf("\nGeometries of known disks:\n");
2400 			bip = &dl->dl_biosdisks[i];
2401 			printf("Disk %d: cylinders %u, heads %u, sectors %u"
2402 				" (%"PRIdaddr" sectors, %dMB)\n",
2403 			    i, bip->bi_cyl, bip->bi_head, bip->bi_sec,
2404 			    bip->bi_lbasecs, SEC_TO_MB(bip->bi_lbasecs));
2405 
2406 		}
2407 		printf("\n");
2408 	}
2409 #endif
2410 	do {
2411 		dos_cylinders = decimal("BIOS's idea of #cylinders",
2412 					dos_cylinders, 0, 0, MAXCYL);
2413 		dos_heads = decimal("BIOS's idea of #heads",
2414 					dos_heads, 0, 0, MAXHEAD);
2415 		dos_sectors = decimal("BIOS's idea of #sectors",
2416 					dos_sectors, 0, 1, MAXSECTOR);
2417 		print_geometry();
2418 	} while (!yesno("Are you happy with this choice?"));
2419 }
2420 
2421 
2422 /***********************************************\
2423 * Change real numbers into strange dos numbers	*
2424 \***********************************************/
2425 static void
2426 dos(int sector, unsigned char *cylinderp, unsigned char *headp,
2427     unsigned char *sectorp)
2428 {
2429 	int cylinder, head;
2430 
2431 	cylinder = sector / dos_cylindersectors;
2432 	sector -= cylinder * dos_cylindersectors;
2433 
2434 	head = sector / dos_sectors;
2435 	sector -= head * dos_sectors;
2436 	if (cylinder > 1023)
2437 		cylinder = 1023;
2438 
2439 	*cylinderp = DOSCYL(cylinder);
2440 	*headp = head;
2441 	*sectorp = DOSSECT(sector + 1, cylinder);
2442 }
2443 
2444 static int
2445 open_disk(int update)
2446 {
2447 	static char namebuf[MAXPATHLEN + 1];
2448 	int flags = update && disk_file == NULL ? O_RDWR : O_RDONLY;
2449 
2450 	if (!F_flag) {
2451 		fd = opendisk(disk, flags, namebuf, sizeof(namebuf), 0);
2452 		if (fd < 0) {
2453 			if (errno == ENODEV)
2454 				warnx("%s is not a character device", namebuf);
2455 			else
2456 				warn("cannot opendisk %s", namebuf);
2457 			return (-1);
2458 		}
2459 		disk = namebuf;
2460 	} else {
2461 		fd = open(disk, flags, 0);
2462 		if (fd == -1) {
2463 			warn("cannot open %s", disk);
2464 			return -1;
2465 		}
2466 	}
2467 
2468 	if (get_params() == -1) {
2469 		close(fd);
2470 		fd = -1;
2471 		return (-1);
2472 	}
2473 	if (disk_file != NULL) {
2474 		/* for testing: read/write data from a disk file */
2475 		wfd = open(disk_file, update ? O_RDWR|O_CREAT : O_RDONLY, 0777);
2476 		if (wfd == -1) {
2477 			warn("%s", disk_file);
2478 			close(fd);
2479 			fd = -1;
2480 			return -1;
2481 		}
2482 	} else
2483 		wfd = fd;
2484 	return (0);
2485 }
2486 
2487 static ssize_t
2488 read_disk(daddr_t sector, void *buf)
2489 {
2490 	ssize_t nr;
2491 
2492 	if (*rfd == -1)
2493 		errx(1, "read_disk(); fd == -1");
2494 
2495 	off_t offs = sector * (off_t)secsize;
2496 	off_t mod = offs & (secsize - 1);
2497 	off_t rnd = offs & ~(secsize - 1);
2498 
2499 	if (lseek(*rfd, rnd, SEEK_SET) == (off_t)-1)
2500 		return -1;
2501 
2502 	if (secsize == 512)
2503 		return read(*rfd, buf, 512);
2504 
2505 	if ((nr = read(*rfd, iobuf, secsize)) != secsize)
2506 		return nr;
2507 
2508 	memcpy(buf, &iobuf[mod], 512);
2509 
2510 	return 512;
2511 }
2512 
2513 static ssize_t
2514 write_disk(daddr_t sector, void *buf)
2515 {
2516 	ssize_t nr;
2517 
2518 	if (wfd == -1)
2519 		errx(1, "write_disk(); wfd == -1");
2520 
2521 	off_t offs = sector * (off_t)secsize;
2522 	off_t mod = offs & (secsize - 1);
2523 	off_t rnd = offs & ~(secsize - 1);
2524 
2525 	if (lseek(wfd, rnd, SEEK_SET) == (off_t)-1)
2526 		return -1;
2527 
2528 	if (secsize == 512)
2529 		return write(wfd, buf, 512);
2530 
2531 	if ((nr = read(wfd, iobuf, secsize)) != secsize)
2532 		return nr;
2533 
2534 	if (lseek(wfd, rnd, SEEK_SET) == (off_t)-1)
2535 		return -1;
2536 
2537 	memcpy(&iobuf[mod], buf, 512);
2538 
2539 	if ((nr = write(wfd, iobuf, secsize)) != secsize)
2540 		return nr;
2541 
2542 	return 512;
2543 }
2544 
2545 static void
2546 guess_geometry(daddr_t _sectors)
2547 {
2548 	dos_sectors = MAXSECTOR;
2549 	dos_heads = MAXHEAD - 1;	/* some BIOS might use 256 */
2550 	dos_cylinders = _sectors / (MAXSECTOR * (MAXHEAD - 1));
2551 	if (dos_cylinders < 1)
2552 		dos_cylinders = 1;
2553 	else if (dos_cylinders > MAXCYL - 1)
2554 		dos_cylinders = MAXCYL - 1;
2555 }
2556 
2557 static int
2558 get_params(void)
2559 {
2560 	if (disk_type != NULL) {
2561 		struct disklabel *tmplabel;
2562 
2563 		if ((tmplabel = getdiskbyname(disk_type)) == NULL) {
2564 			warn("bad disktype");
2565 			return (-1);
2566 		}
2567 		disklabel = *tmplabel;
2568 	} else if (F_flag) {
2569 		struct stat st;
2570 		if (fstat(fd, &st) == -1) {
2571 			warn("fstat");
2572 			return (-1);
2573 		}
2574 		if (st.st_size % 512 != 0) {
2575 			warnx("%s size (%lld) is not divisible "
2576 			    "by sector size (%d)", disk, (long long)st.st_size,
2577 			    512);
2578 		}
2579 		disklabel.d_secperunit = st.st_size / 512;
2580 		guess_geometry(disklabel.d_secperunit);
2581 		disklabel.d_ncylinders = dos_cylinders;
2582 		disklabel.d_ntracks = dos_heads;
2583 		disklabel.d_secsize = 512;
2584 		disklabel.d_nsectors = dos_sectors;
2585 	} else if (ioctl(fd, DIOCGDEFLABEL, &disklabel) == -1) {
2586 		warn("DIOCGDEFLABEL");
2587 		if (ioctl(fd, DIOCGDINFO, &disklabel) == -1) {
2588 			warn("DIOCGDINFO");
2589 			return (-1);
2590 		}
2591 	}
2592 
2593 	disksectors = disklabel.d_secperunit;
2594 	cylinders = disklabel.d_ncylinders;
2595 	heads = disklabel.d_ntracks;
2596 	secsize = disklabel.d_secsize;
2597 	sectors = disklabel.d_nsectors;
2598 
2599 	/* pick up some defaults for the BIOS sizes */
2600 	if (sectors <= MAXSECTOR) {
2601 		dos_cylinders = cylinders;
2602 		dos_heads = heads;
2603 		dos_sectors = sectors;
2604 	} else {
2605 		/* guess - has to better than the above */
2606 		guess_geometry(disksectors);
2607 	}
2608 	dos_disksectors = disksectors;
2609 
2610 	return (0);
2611 }
2612 
2613 #ifdef BOOTSEL
2614 /*
2615  * Rather unfortunately the bootsel 'magic' number is at the end of the
2616  * the structure, and there is no checksum.  So when other operating
2617  * systems install mbr code by only writing the length of their code they
2618  * can overwrite part of the structure but keeping the magic number intact.
2619  * This code attempts to empirically detect this problem.
2620  */
2621 static int
2622 validate_bootsel(struct mbr_bootsel *mbs)
2623 {
2624 	unsigned int key = mbs->mbrbs_defkey;
2625 	unsigned int tmo;
2626 	size_t i;
2627 
2628 	if (v_flag)
2629 		return 0;
2630 
2631 	/*
2632 	 * Check default key is sane
2633 	 * - this is the most likely field to be stuffed
2634 	 * 16 disks and 16 bootable partitions seems enough!
2635 	 * (the keymap decode starts falling apart at that point)
2636 	 */
2637 	if (mbs->mbrbs_flags & MBR_BS_ASCII) {
2638 		if (key != 0 && !(key == '\r'
2639 		    || (key >= '1' && key < '1' + MAX_BIOS_DISKS)
2640 		    || (key >= 'a' && key < 'a' + MAX_BIOS_DISKS)))
2641 			return 1;
2642 	} else {
2643 		if (key != 0 && !(key == SCAN_ENTER
2644 		    || (key >= SCAN_1 && key < SCAN_1 + MAX_BIOS_DISKS)
2645 		    || (key >= SCAN_F1 && key < SCAN_F1 + MAX_BIOS_DISKS)))
2646 			return 1;
2647 	}
2648 
2649 	/* Checking the flags will lead to breakage... */
2650 
2651 	/* Timeout value is expected to be a multiple of a second */
2652 	tmo = htole16(mbs->mbrbs_timeo);
2653 	if (tmo != 0 && tmo != 0xffff && tmo != (10 * tmo + 9) / 182 * 182 / 10)
2654 		return 2;
2655 
2656 	/* Check the menu strings are printable */
2657 	/* Unfortunately they aren't zero filled... */
2658 	for (i = 0; i < sizeof(mbs->mbrbs_nametab); i++) {
2659 		int c = (uint8_t)mbs->mbrbs_nametab[0][i];
2660 		if (c == 0 || isprint(c))
2661 			continue;
2662 		return 3;
2663 	}
2664 
2665 	return 0;
2666 }
2667 #endif
2668 
2669 static int
2670 read_s0(daddr_t offset, struct mbr_sector *boot)
2671 {
2672 	const char *tabletype = offset ? "extended" : "primary";
2673 #ifdef BOOTSEL
2674 	static int reported;
2675 #endif
2676 
2677 	if (read_disk(offset, boot) == -1) {
2678 		warn("Can't read %s partition table", tabletype);
2679 		return -1;
2680 	}
2681 	if (boot->mbr_magic != LE_MBR_MAGIC) {
2682 		if (F_flag && boot->mbr_magic == 0)
2683 			return -1;
2684 		warnx("%s partition table invalid, "
2685 		    "no magic in sector %"PRIdaddr, tabletype, offset);
2686 		return -1;
2687 
2688 	}
2689 #ifdef BOOTSEL
2690 	if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
2691 		/* mbr_bootsel in new location */
2692 		if (validate_bootsel(&boot->mbr_bootsel)) {
2693 			warnx("removing corrupt bootsel information");
2694 			boot->mbr_bootsel_magic = 0;
2695 		}
2696 		return 0;
2697 	}
2698 	if (boot->mbr_bootsel_magic != LE_MBR_MAGIC)
2699 		return 0;
2700 
2701 	/* mbr_bootsel in old location */
2702 	if (!reported)
2703 		warnx("%s partition table: using old-style bootsel information",
2704 		    tabletype);
2705 	reported = 1;
2706 	if (validate_bootsel((void *)((uint8_t *)boot + MBR_BS_OFFSET + 4))) {
2707 		warnx("%s bootsel information corrupt - ignoring", tabletype);
2708 		return 0;
2709 	}
2710 	memmove((uint8_t *)boot + MBR_BS_OFFSET,
2711 		(uint8_t *)boot + MBR_BS_OFFSET + 4,
2712 		sizeof(struct mbr_bootsel));
2713 	if ( ! (boot->mbr_bootsel.mbrbs_flags & MBR_BS_NEWMBR)) {
2714 			/* old style default key */
2715 		int id;
2716 			/* F1..F4 => ptn 0..3, F5+ => disk 0+ */
2717 		id = boot->mbr_bootsel.mbrbs_defkey;
2718 		id -= SCAN_F1;
2719 		if (id >= MBR_PART_COUNT)
2720 			id -= MBR_PART_COUNT; /* Use number of disk */
2721 		else if (mboot.mbr_parts[id].mbrp_type != 0)
2722 			id = le32toh(boot->mbr_parts[id].mbrp_start);
2723 		else
2724 			id = DEFAULT_ACTIVE;
2725 		boot->mbr_bootsel.mbrbs_defkey = id;
2726 	}
2727 	boot->mbr_bootsel_magic = LE_MBR_BS_MAGIC;
2728 		/* highlight that new bootsel code is necessary */
2729 	boot->mbr_bootsel.mbrbs_flags &= ~MBR_BS_NEWMBR;
2730 #endif /* BOOTSEL */
2731 	return 0;
2732 }
2733 
2734 static int
2735 write_mbr(void)
2736 {
2737 	int flag, i;
2738 	daddr_t offset;
2739 	int rval = -1;
2740 
2741 	/*
2742 	 * write enable label sector before write (if necessary),
2743 	 * disable after writing.
2744 	 * needed if the disklabel protected area also protects
2745 	 * sector 0. (e.g. empty disk)
2746 	 */
2747 	flag = 1;
2748 	if (wfd == fd && F_flag == 0 && ioctl(wfd, DIOCWLABEL, &flag) < 0)
2749 		warn("DIOCWLABEL");
2750 	if (write_disk(0, &mboot) == -1) {
2751 		warn("Can't write fdisk partition table");
2752 		goto protect_label;
2753 	}
2754 	if (boot_installed)
2755 		for (i = bootsize; (i -= 0x200) > 0;)
2756 			if (write_disk(i / 0x200, &bootcode[i / 0x200]) == -1) {
2757 				warn("Can't write bootcode");
2758 				goto protect_label;
2759 			}
2760 	for (offset = 0, i = 0; i < ext.num_ptn; i++) {
2761 		if (write_disk(ext.base + offset, ext.ptn + i) == -1) {
2762 			warn("Can't write %dth extended partition", i);
2763 			goto protect_label;
2764 		}
2765 		offset = le32toh(ext.ptn[i].mbr_parts[1].mbrp_start);
2766 	}
2767 	rval = 0;
2768     protect_label:
2769 	flag = 0;
2770 	if (wfd == fd && F_flag == 0 && ioctl(wfd, DIOCWLABEL, &flag) < 0)
2771 		warn("DIOCWLABEL");
2772 	return rval;
2773 }
2774 
2775 static int
2776 yesno(const char *str, ...)
2777 {
2778 	int ch, first;
2779 	va_list ap;
2780 
2781 	va_start(ap, str);
2782 	vprintf(str, ap);
2783 	va_end(ap);
2784 	printf(" [n] ");
2785 
2786 	first = ch = getchar();
2787 	while (ch != '\n' && ch != EOF)
2788 		ch = getchar();
2789 	if (ch == EOF)
2790 		errx(1, "EOF");
2791 	return (first == 'y' || first == 'Y');
2792 }
2793 
2794 static int64_t
2795 decimal(const char *prompt, int64_t dflt, int flags, int64_t minval, int64_t maxval)
2796 {
2797 	int64_t acc = 0;
2798 	int valid;
2799 	int len;
2800 	char *cp;
2801 
2802 	for (;;) {
2803 		if (flags & DEC_SEC) {
2804 			printf("%s: [%" PRId64 "..%" PRId64 "cyl default: %" PRId64 ", %" PRId64 "cyl, %uMB] ",
2805 			    prompt, SEC_TO_CYL(minval), SEC_TO_CYL(maxval),
2806 			    dflt, SEC_TO_CYL(dflt), SEC_TO_MB(dflt));
2807 		} else
2808 			printf("%s: [%" PRId64 "..%" PRId64 " default: %" PRId64 "] ",
2809 			    prompt, minval, maxval, dflt);
2810 
2811 		if (!fgets(lbuf, LBUF, stdin))
2812 			errx(1, "EOF");
2813 		cp = lbuf;
2814 
2815 		cp += strspn(cp, " \t");
2816 		if (*cp == '\n')
2817 			return dflt;
2818 
2819 		if (cp[0] == '$' && cp[1] == '\n')
2820 			return maxval;
2821 
2822 		if (isdigit((unsigned char)*cp) || *cp == '-') {
2823 			acc = strtoll(lbuf, &cp, 10);
2824 			len = strcspn(cp, " \t\n");
2825 			valid = 0;
2826 			if (len != 0 && (flags & DEC_SEC)) {
2827 				if (!strncasecmp(cp, "gb", len)) {
2828 					acc *= 1024;
2829 					valid = 1;
2830 				}
2831 				if (valid || !strncasecmp(cp, "mb", len)) {
2832 					acc *= SEC_IN_1M;
2833 					/* round to whole number of cylinders */
2834 					acc += ptn_alignment / 2;
2835 					acc /= ptn_alignment;
2836 					valid = 1;
2837 				}
2838 				if (valid || !strncasecmp(cp, "cyl", len)) {
2839 					acc *= ptn_alignment;
2840 					/* adjustments for cylinder boundary */
2841 					if (acc == 0 && flags & DEC_RND_0)
2842 						acc += ptn_0_offset;
2843 					if (flags & DEC_RND)
2844 						acc += ptn_0_offset;
2845 					if (flags & DEC_RND_DOWN)
2846 						acc -= ptn_0_offset;
2847 					if (flags & DEC_RND_DOWN_2)
2848 						acc -= ptn_0_offset;
2849 					cp += len;
2850 				}
2851 			}
2852 		}
2853 
2854 		cp += strspn(cp, " \t");
2855 		if (*cp != '\n') {
2856 			lbuf[strlen(lbuf) - 1] = 0;
2857 			printf("%s is not a valid %s number.\n", lbuf,
2858 			    flags & DEC_SEC ? "sector" : "decimal");
2859 			continue;
2860 		}
2861 
2862 		if (acc >= minval && acc <= maxval)
2863 			return acc;
2864 		printf("%" PRId64 " is not between %" PRId64 " and %" PRId64 ".\n", acc, minval, maxval);
2865 	}
2866 }
2867 
2868 static int
2869 ptn_id(const char *prompt, int *extended)
2870 {
2871 	unsigned int acc = 0;
2872 	char *cp;
2873 
2874 	for (;; printf("%s is not a valid partition number.\n", lbuf)) {
2875 		printf("%s: [none] ", prompt);
2876 
2877 		if (!fgets(lbuf, LBUF, stdin))
2878 			errx(1, "EOF");
2879 		lbuf[strlen(lbuf)-1] = '\0';
2880 		cp = lbuf;
2881 
2882 		cp += strspn(cp, " \t");
2883 		*extended = 0;
2884 		if (*cp == 0)
2885 			return -1;
2886 
2887 		if (*cp == 'E' || *cp == 'e') {
2888 			cp++;
2889 			*extended = 1;
2890 		}
2891 
2892 		acc = strtoul(cp, &cp, 10);
2893 
2894 		cp += strspn(cp, " \t");
2895 		if (*cp != '\0')
2896 			continue;
2897 
2898 		if (*extended || acc < MBR_PART_COUNT)
2899 			return acc;
2900 	}
2901 }
2902 
2903 #ifdef BOOTSEL
2904 static void
2905 string(const char *prompt, int length, char *buf)
2906 {
2907 	int len;
2908 
2909 	for (;;) {
2910 		printf("%s: [%.*s] ", prompt, length, buf);
2911 
2912 		if (!fgets(lbuf, LBUF, stdin))
2913 			errx(1, "EOF");
2914 		len = strlen(lbuf);
2915 		if (len <= 1)
2916 			/* unchanged if just <enter> */
2917 			return;
2918 		/* now strip trailing spaces, <space><enter> deletes string */
2919 		do
2920 			lbuf[--len] = 0;
2921 		while (len != 0 && lbuf[len - 1] == ' ');
2922 		if (len < length)
2923 			break;
2924 		printf("'%s' is longer than %d characters.\n",
2925 		    lbuf, length - 1);
2926 	}
2927 	strncpy(buf, lbuf, length);
2928 }
2929 #endif
2930 
2931 static int
2932 type_match(const void *key, const void *item)
2933 {
2934 	const int *idp = key;
2935 	const struct mbr_ptype *ptr = item;
2936 
2937 	if (*idp < ptr->id)
2938 		return (-1);
2939 	if (*idp > ptr->id)
2940 		return (1);
2941 	return (0);
2942 }
2943 
2944 static const char *
2945 get_type(int type)
2946 {
2947 	struct mbr_ptype *ptr;
2948 
2949 	ptr = bsearch(&type, mbr_ptypes, KNOWN_SYSIDS,
2950 	    sizeof(mbr_ptypes[0]), type_match);
2951 	if (ptr == 0)
2952 		return ("unknown");
2953 	return (ptr->name);
2954 }
2955 
2956 static int
2957 read_gpt(daddr_t offset, struct gpt_hdr *gptp)
2958 {
2959 	char buf[512];
2960 	struct gpt_hdr *hdr = (void *)buf;
2961 	const char *tabletype = GPT_TYPE(offset);
2962 
2963 	if (read_disk(offset, buf) == -1) {
2964 		warn("Can't read %s GPT header", tabletype);
2965 		return -1;
2966 	}
2967 	(void)memcpy(gptp, buf, GPT_HDR_SIZE);
2968 
2969 	/* GPT CRC should be calculated with CRC field preset to zero */
2970 	hdr->hdr_crc_self = 0;
2971 
2972 	if (memcmp(gptp->hdr_sig, GPT_HDR_SIG, sizeof(gptp->hdr_sig))
2973 	    || gptp->hdr_lba_self != (uint64_t)offset
2974 	    || crc32(0, (void *)hdr, gptp->hdr_size) != gptp->hdr_crc_self) {
2975 		/* not a GPT */
2976 		(void)memset(gptp, 0, GPT_HDR_SIZE);
2977 	}
2978 
2979 	if (v_flag && gptp->hdr_size != 0) {
2980 		printf("Found %s GPT header CRC %"PRIu32" "
2981 		    "at sector %"PRIdaddr", backup at %"PRIdaddr"\n",
2982 		    tabletype, gptp->hdr_crc_self, offset, gptp->hdr_lba_alt);
2983 	}
2984 	return gptp->hdr_size;
2985 
2986 }
2987 
2988 static int
2989 delete_gpt(struct gpt_hdr *gptp)
2990 {
2991 	char buf[512];
2992 	struct gpt_hdr *hdr = (void *)buf;
2993 
2994 	if (gptp->hdr_size == 0)
2995 		return 0;
2996 
2997 	/* don't accidently overwrite something important */
2998 	if (gptp->hdr_lba_self != GPT_HDR_BLKNO &&
2999 	    gptp->hdr_lba_self != (uint64_t)disksectors - 1) {
3000 		warnx("given GPT header location doesn't seem correct");
3001 		return -1;
3002 	}
3003 
3004 	(void)memcpy(buf, gptp, GPT_HDR_SIZE);
3005 	/*
3006 	 * Don't really delete GPT, just "disable" it, so it can
3007 	 * be recovered later in case of mistake or something
3008 	 */
3009 	(void)memset(hdr->hdr_sig, 0, sizeof(gptp->hdr_sig));
3010 	if (write_disk(gptp->hdr_lba_self, hdr) == -1) {
3011 		warn("can't delete %s GPT header",
3012 		    GPT_TYPE(gptp->hdr_lba_self));
3013 		return -1;
3014 	}
3015 	(void)memset(gptp, 0, GPT_HDR_SIZE);
3016 	return 1;
3017 }
3018