xref: /netbsd-src/sbin/fdisk/fdisk.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: fdisk.c,v 1.150 2014/04/04 16:15:30 christos 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 1.150 2014/04/04 16:15:30 christos 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 static int
325 getnum(const char *str, int *num)
326 {
327 	char *e;
328 	long l;
329 
330 	errno = 0;
331 	l = strtol(str, &e, 0);
332 	if (str[0] == '\0' || *e != '\0')
333 		return -1;
334 	if (errno == ERANGE && (l == LONG_MAX || l == LONG_MIN))
335 		return -1;
336 	/* XXX: truncation */
337 	*num = (int)l;
338 	return 0;
339 }
340 
341 /* [<sysid>][/[<start>][/[<size>][/[<bootmenu>]]]] */
342 static int
343 parse_s(char *arg, int *csysid, unsigned *cstart, unsigned *csize,
344     char **cbootmenu)
345 {
346 	char *ptr;
347 	int num;
348 
349 	if ((ptr = strchr(arg, '/')) != NULL)
350 		*ptr++ = '\0';
351 
352 	if (*arg) {
353 		if (getnum(arg, &num) == -1)
354 			return -1;
355 		*csysid = num;
356 	}
357 	if (ptr == NULL)
358 		return 0;
359 
360 	arg = ptr;
361 	if ((ptr = strchr(arg, '/')) != NULL)
362 		*ptr++ = '\0';
363 	if (*arg) {
364 		if (getnum(arg, &num) == -1)
365 			return -1;
366 		*cstart = num;
367 	}
368 	if (ptr == NULL)
369 		return 0;
370 
371 	arg = ptr;
372 	if ((ptr = strchr(arg, '/')) != NULL)
373 		*ptr++ = '\0';
374 	if (*arg) {
375 		if (getnum(arg, &num) == -1)
376 			return -1;
377 		*csize = num;
378 	}
379 	if (ptr != NULL && *ptr)
380 		*cbootmenu = ptr;
381 	return 0;
382 }
383 
384 int
385 main(int argc, char *argv[])
386 {
387 	struct stat sb;
388 	int ch;
389 	size_t len;
390 	char *cp;
391 	int n;
392 #ifdef BOOTSEL
393 	daddr_t default_ptn;		/* start sector of default ptn */
394 #endif
395 	char *cbootmenu = 0;
396 
397 	int csysid;	/* For the s_flag. */
398 	unsigned int cstart, csize;
399 	a_flag = u_flag = sh_flag = f_flag = s_flag = b_flag = 0;
400 	i_flag = B_flag = 0;
401 	v_flag = 0;
402 	E_flag = 0;
403 	csysid = -1;
404 	cstart = csize = ~0;
405 	while ((ch = getopt(argc, argv, OPTIONS)) != -1) {
406 		switch (ch) {
407 		case '0':
408 			partition = 0;
409 			break;
410 		case '1':
411 			partition = 1;
412 			break;
413 		case '2':
414 			partition = 2;
415 			break;
416 		case '3':
417 			partition = 3;
418 			break;
419 		case 'E':	/* Extended partition number */
420 			E_flag = 1;
421 			partition = strtoul(optarg, &cp, 0);
422 			if (*cp || partition < 0)
423 				errx(1, "Bad partition number -E %s.", optarg);
424 			break;
425 #ifdef BOOTSEL
426 		case 'B':	/* Bootselect parameters */
427 			B_flag = 1;
428 			break;
429 #endif
430 		case 'F':	/* device argument is really a file */
431 			F_flag = 1;
432 			break;
433 		case 'S':	/* Output as shell variables */
434 			sh_flag = 1;
435 			break;
436 		case 'a':	/* Set active partition */
437 			a_flag = 1;
438 			break;
439 		case 'f':	/* Non interactive */
440 			f_flag = 1;
441 			break;
442 		case 'i':	/* Always update bootcode */
443 			i_flag = 1;
444 			break;
445 		case 'I':	/* Ignore errors */
446 			I_flag = 1;
447 			break;
448 		case 'l':	/* List known partition types */
449 			for (len = 0; len < KNOWN_SYSIDS; len++)
450 				printf("%03d %s\n", mbr_ptypes[len].id,
451 				    mbr_ptypes[len].name);
452 			return 0;
453 		case 'u':	/* Update partition details */
454 			u_flag = 1;
455 			break;
456 		case 'v':	/* Be verbose */
457 			v_flag++;
458 			break;
459 		case 's':	/* Partition details */
460 			s_flag = 1;
461 
462 			if (parse_s(optarg, &csysid, &cstart, &csize,
463 			    &cbootmenu) == -1)
464 				errx(1, "Bad argument to the -s flag.");
465 			break;
466 		case 'b':	/* BIOS geometry */
467 			b_flag = 1;
468 			if (sscanf(optarg, "%d/%d/%d%n", &b_cyl, &b_head,
469 			    &b_sec, &n) != 3 || optarg[n] != 0)
470 				errx(1, "Bad argument to the -b flag.");
471 			if (b_cyl > MAXCYL)
472 				b_cyl = MAXCYL;
473 			break;
474 		case 'A':	/* Partition alignment[/offset] */
475 			if (sscanf(optarg, "%u%n/%u%n", &ptn_alignment,
476 				    &n, &ptn_0_offset, &n) < 1
477 			    || optarg[n] != 0
478 			    || ptn_0_offset > ptn_alignment)
479 				errx(1, "Bad argument to the -A flag.");
480 			if (ptn_0_offset == 0)
481 				ptn_0_offset = ptn_alignment;
482 			break;
483 		case 'c':	/* file/directory containing boot code */
484 			if (strchr(optarg, '/') != NULL &&
485 			    stat(optarg, &sb) == 0 &&
486 			    (sb.st_mode & S_IFMT) == S_IFDIR) {
487 				boot_dir = optarg;
488 				break;
489 			}
490 			bootsize = read_boot(optarg, bootcode,
491 						sizeof bootcode, 1);
492 			i_flag = 1;
493 			break;
494 		case 'r':	/* read data from disk_file (not raw disk) */
495 			rfd = &wfd;
496 			/* FALLTHROUGH */
497 		case 'w':	/* write data to disk_file */
498 			disk_file = optarg;
499 			break;
500 		case 't':
501 			if (setdisktab(optarg) == -1)
502 				errx(EXIT_FAILURE, "bad disktab");
503 			break;
504 		case 'T':
505 			disk_type = optarg;
506 			break;
507 		case 'z':
508 			secsize = atoi(optarg);
509 			if (secsize <= 512)
510 out:				 errx(EXIT_FAILURE, "Invalid sector size %zd",
511 				    secsize);
512 			for (ch = secsize; (ch & 1) == 0; ch >>= 1)
513 				continue;
514 			if (ch != 1)
515 				goto out;
516 			break;
517 		default:
518 			usage();
519 		}
520 	}
521 	argc -= optind;
522 	argv += optind;
523 
524 	if (disk_type != NULL && getdiskbyname(disk_type) == NULL)
525 		errx(EXIT_FAILURE, "bad disktype");
526 
527 	if (sh_flag && (a_flag || i_flag || u_flag || f_flag || s_flag))
528 		usage();
529 
530 	if (B_flag && f_flag) {
531 		warnx("Bootselector may only be configured interactively");
532 		usage();
533 	}
534 
535 	if (f_flag && u_flag && !s_flag) {
536 		warnx("Partition data not specified");
537 		usage();
538 	}
539 
540 	if (s_flag && partition == -1) {
541 		warnx("-s flag requires a partition selected.");
542 		usage();
543 	}
544 
545 	if (argc > 1)
546 		usage();
547 
548 	if (argc > 0)
549 		disk = argv[0];
550 	else if (!F_flag) {
551 		/* Default to boot device */
552 		initvar_disk(&disk);
553 	}
554 
555 	if (!F_flag && stat(disk, &sb) == 0 && S_ISREG(sb.st_mode))
556 		F_flag = 1;
557 
558 	if (open_disk(B_flag || a_flag || i_flag || u_flag) < 0)
559 		exit(1);
560 
561 	if (secsize > 512) {
562 		if ((iobuf = malloc(secsize)) == NULL)
563 			err(EXIT_FAILURE, "Cannot allocate %zd buffer",
564 			    secsize);
565 	}
566 
567 	if (read_s0(0, &mboot))
568 		/* must have been a blank disk */
569 		init_sector0(1);
570 
571 	read_gpt(GPT_HDR_BLKNO, &gpt1);
572 	read_gpt(disksectors - 1, &gpt2);
573 
574 	if (b_flag) {
575 		dos_cylinders = b_cyl;
576 		dos_heads = b_head;
577 		dos_sectors = b_sec;
578 	} else {
579 		get_bios_geometry();
580 	}
581 
582 	if (ptn_alignment == 0)
583 		get_ptn_alignmemt();
584 
585 	get_extended_ptn();
586 
587 #ifdef BOOTSEL
588 	default_ptn = get_default_boot();
589 #endif
590 
591 	if (E_flag && !u_flag && partition >= ext.num_ptn)
592 		errx(1, "Extended partition %d is not defined.", partition);
593 
594 	/* Do the update stuff! */
595 	if (u_flag) {
596 		if (!f_flag && !b_flag)
597 			change_bios_geometry();
598 
599 		if (s_flag)
600 			change_part(E_flag, partition, csysid, cstart, csize,
601 				cbootmenu);
602 		else {
603 			int part = partition, chg_ext = E_flag, prompt = 1;
604 			do {
605 				if (prompt) {
606 					printf("\n");
607 					print_s0(partition);
608 				}
609 				if (partition == -1)
610 					part = ptn_id(
611 				    "Which partition do you want to change?",
612 							&chg_ext);
613 				if (part < 0)
614 					break;
615 				prompt = change_part(chg_ext, part, 0, 0, 0, 0);
616 			} while (partition == -1);
617 		}
618 	} else {
619 		if (!i_flag && !B_flag) {
620 			print_geometry();
621 			print_s0(partition);
622 		}
623 	}
624 
625 	if (a_flag && !E_flag)
626 		change_active(partition);
627 
628 #ifdef BOOTSEL
629 	if (B_flag || u_flag || i_flag)
630 		/* Ensure the mbr code supports this configuration */
631 		install_bootsel(0);
632 	if (B_flag)
633 		default_ptn = configure_bootsel(default_ptn);
634 	set_default_boot(default_ptn);
635 #else
636 	if (i_flag)
637 		init_sector0(0);
638 #endif
639 
640 	if (u_flag || a_flag || i_flag || B_flag) {
641 		if (!f_flag) {
642 			printf("\nWe haven't written the MBR back to disk "
643 			       "yet.  This is your last chance.\n");
644 			if (u_flag)
645 				print_s0(-1);
646 			if (gpt1.hdr_size != 0 || gpt2.hdr_size != 0)
647 				printf("\nWARNING: The disk is carrying "
648 				       "GUID Partition Tables.\n"
649 				       "         If you continue, "
650 				       "GPT headers will be deleted.\n\n");
651 			if (yesno("Should we write new partition table?")) {
652 				delete_gpt(&gpt1);
653 				delete_gpt(&gpt2);
654 				write_mbr();
655 			}
656 		} else {
657 			if (delete_gpt(&gpt1) > 0)
658 				warnx("Primary GPT header was deleted");
659 			if (delete_gpt(&gpt2) > 0)
660 				warnx("Secondary GPT header was deleted");
661 			write_mbr();
662 		}
663 	}
664 
665 	exit(0);
666 }
667 
668 static void
669 usage(void)
670 {
671 	int indent = 7 + (int)strlen(getprogname()) + 1;
672 
673 	(void)fprintf(stderr, "usage: %s [-aBFfIilSuv] "
674 		"[-A ptn_alignment[/ptn_0_offset]] \\\n"
675 		"%*s[-b cylinders/heads/sectors] \\\n"
676 		"%*s[-0123 | -E num "
677 		"[-s [id][/[start][/[size][/bootmenu]]]] \\\n"
678 		"%*s[-t disktab] [-T disktype] \\\n"
679 		"%*s[-c bootcode] "
680 		"[-r|-w file] [device]\n"
681 		"\t-a change active partition\n"
682 		"\t-f force - not interactive\n"
683 		"\t-i initialise MBR code\n"
684 		"\t-I ignore errors about no space or overlapping partitions\n"
685 		"\t-l list partition types\n"
686 		"\t-u update partition data\n"
687 		"\t-v verbose output, -v -v more verbose still\n"
688 		"\t-B update bootselect options\n"
689 		"\t-F treat device as a regular file\n"
690 		"\t-S output as shell defines\n"
691 		"\t-r and -w access 'file' for non-destructive testing\n",
692 		getprogname(), indent, "", indent, "", indent, "", indent, "");
693 	exit(1);
694 }
695 
696 static daddr_t
697 ext_offset(int part)
698 {
699 	daddr_t offset = ext.base;
700 
701 	if (part != 0)
702 		offset += le32toh(ext.ptn[part - 1].mbr_parts[1].mbrp_start);
703 	return offset;
704 }
705 
706 static void
707 print_s0(int which)
708 {
709 	int part;
710 
711 	if (which == -1) {
712 		if (!sh_flag)
713 			printf("Partition table:\n");
714 		for (part = 0; part < MBR_PART_COUNT; part++) {
715 			if (!sh_flag)
716 				printf("%d: ", part);
717 			print_part(&mboot, part, 0);
718 		}
719 		if (!sh_flag) {
720 			if (ext.is_corrupt)
721 				printf("Extended partition table is corrupt\n");
722 			else
723 				if (ext.num_ptn != 0)
724 					printf("Extended partition table:\n");
725 		}
726 		for (part = 0; part < ext.num_ptn; part++) {
727 			if (!sh_flag)
728 				printf("E%d: ", part);
729 			print_part(&ext.ptn[part], 0, ext_offset(part));
730 			if (!sh_flag && v_flag >= 2) {
731 				printf("link: ");
732 				print_mbr_partition(&ext.ptn[part], 1,
733 						ext_offset(part), ext.base, 0);
734 			}
735 		}
736 #ifdef BOOTSEL
737 		if (!sh_flag && mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
738 			int tmo;
739 
740 			printf("Bootselector ");
741 			if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ACTIVE) {
742 				printf("enabled");
743 				tmo = le16toh(mboot.mbr_bootsel.mbrbs_timeo);
744 				if (tmo == 0xffff)
745 					printf(", infinite timeout");
746 				else
747 					printf(", timeout %d seconds",
748 						    (10 * tmo + 9) / 182);
749 			} else
750 				printf("disabled");
751 			printf(".\n");
752 		}
753 #endif
754 		if (!sh_flag) {
755 			int active = first_active();
756 			if (active == MBR_PART_COUNT)
757 				printf("No active partition.\n");
758 			else
759 				printf("First active partition: %d\n", active);
760 		}
761 		if (!sh_flag)
762 			printf("Drive serial number: %"PRIu32" (0x%08x)\n",
763 			    le32toh(mboot.mbr_dsn),
764 			    le32toh(mboot.mbr_dsn));
765 		return;
766 	}
767 
768 	if (E_flag) {
769 		if (!sh_flag)
770 			printf("Extended partition E%d:\n", which);
771 		if (which > ext.num_ptn)
772 			printf("Undefined\n");
773 		else
774 			print_part(&ext.ptn[which], 0, ext_offset(which));
775 	} else {
776 		if (!sh_flag)
777 			printf("Partition %d:\n", which);
778 		print_part(&mboot, which, 0);
779 	}
780 }
781 
782 static void
783 print_part(struct mbr_sector *boot, int part, daddr_t offset)
784 {
785 	struct mbr_partition *partp;
786 	const char *e;
787 
788 	if (!sh_flag) {
789 		print_mbr_partition(boot, part, offset, 0, 0);
790 		return;
791 	}
792 
793 	partp = &boot->mbr_parts[part];
794 	if (boot != &mboot) {
795 		part = boot - ext.ptn;
796 		e = "E";
797 	} else
798 		e = "";
799 
800 	if (partp->mbrp_type == 0) {
801 		printf("PART%s%dSIZE=0\n", e, part);
802 		return;
803 	}
804 
805 	printf("PART%s%dID=%d\n", e, part, partp->mbrp_type);
806 	printf("PART%s%dSIZE=%u\n", e, part, le32toh(partp->mbrp_size));
807 	printf("PART%s%dSTART=%"PRIdaddr"\n", e, part,
808 	    offset + le32toh(partp->mbrp_start));
809 	printf("PART%s%dFLAG=0x%x\n", e, part, partp->mbrp_flag);
810 	printf("PART%s%dBCYL=%d\n", e, part,
811 	    MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect));
812 	printf("PART%s%dBHEAD=%d\n", e, part, partp->mbrp_shd);
813 	printf("PART%s%dBSEC=%d\n", e, part, MBR_PSECT(partp->mbrp_ssect));
814 	printf("PART%s%dECYL=%d\n", e, part,
815 	    MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect));
816 	printf("PART%s%dEHEAD=%d\n", e, part, partp->mbrp_ehd);
817 	printf("PART%s%dESEC=%d\n", e, part, MBR_PSECT(partp->mbrp_esect));
818 }
819 
820 static void
821 pr_cyls(daddr_t sector, int is_end)
822 {
823 	unsigned long cyl, head, sect;
824 	cyl = sector / dos_cylindersectors;
825 	sect = sector - cyl * dos_cylindersectors;
826 	head = sect / dos_sectors;
827 	sect -= head * dos_sectors;
828 
829 	printf("%lu", cyl);
830 
831 	if (is_end) {
832 		if (head == dos_heads - 1 && sect == dos_sectors - 1)
833 			return;
834 	} else {
835 		if (head == 0 && sect == 0)
836 			return;
837 	}
838 
839 	printf("/%lu/%lu", head, sect + 1);
840 }
841 
842 static void
843 print_mbr_partition(struct mbr_sector *boot, int part,
844     daddr_t offset, daddr_t exoffset, int indent)
845 {
846 	daddr_t	start;
847 	daddr_t	size;
848 	struct mbr_partition *partp = &boot->mbr_parts[part];
849 	struct mbr_sector eboot;
850 	int p;
851 	static int dumped = 0;
852 
853 	if (partp->mbrp_type == 0 && v_flag < 2) {
854 		printf("<UNUSED>\n");
855 		return;
856 	}
857 
858 	start = le32toh(partp->mbrp_start);
859 	size = le32toh(partp->mbrp_size);
860 	if (MBR_IS_EXTENDED(partp->mbrp_type))
861 		start += exoffset;
862 	else
863 		start += offset;
864 
865 	printf("%s (sysid %d)\n", get_type(partp->mbrp_type), partp->mbrp_type);
866 #ifdef BOOTSEL
867 	if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC &&
868 	    boot->mbr_bootsel.mbrbs_nametab[part][0])
869 		printf("%*s    bootmenu: %s\n", indent, "",
870 		    boot->mbr_bootsel.mbrbs_nametab[part]);
871 #endif
872 
873 	printf("%*s    start %"PRIdaddr", size %"PRIdaddr,
874 	    indent, "", start, size);
875 	if (size != 0) {
876 		printf(" (%u MB, Cyls ", SEC_TO_MB(size));
877 		if (v_flag == 0 && le32toh(partp->mbrp_start) == ptn_0_offset)
878 			pr_cyls(start - ptn_0_offset, 0);
879 		else
880 			pr_cyls(start, 0);
881 		printf("-");
882 		pr_cyls(start + size - 1, 1);
883 		printf(")");
884 	}
885 
886 	switch (partp->mbrp_flag) {
887 	case 0:
888 		break;
889 	case MBR_PFLAG_ACTIVE:
890 		printf(", Active");
891 		break;
892 	default:
893 		printf(", flag 0x%x", partp->mbrp_flag);
894 		break;
895 	}
896 	printf("\n");
897 
898 	if (v_flag) {
899 		printf("%*s        beg: cylinder %4d, head %3d, sector %2d\n",
900 		    indent, "",
901 		    MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect),
902 		    partp->mbrp_shd, MBR_PSECT(partp->mbrp_ssect));
903 		printf("%*s        end: cylinder %4d, head %3d, sector %2d\n",
904 		    indent, "",
905 		    MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect),
906 		    partp->mbrp_ehd, MBR_PSECT(partp->mbrp_esect));
907 	}
908 
909 	if (partp->mbrp_type == 0 && start == 0 && v_flag < 3)
910 		return;
911 
912 	if (! MBR_IS_EXTENDED(partp->mbrp_type))
913 		print_pbr(start, indent + 8, partp->mbrp_type);
914 
915 	if (!MBR_IS_EXTENDED(partp->mbrp_type) ||
916 	    (v_flag <= 2 && !ext.is_corrupt))
917 		return;
918 
919 	/*
920 	 * Recursive dump extended table,
921 	 * This is read from the disk - so is wrong during editing.
922 	 * Just ensure we only show it once.
923 	 */
924 	if (dumped)
925 		return;
926 
927 	printf("%*s    Extended partition table:\n", indent, "");
928 	indent += 4;
929 	if (read_s0(start, &eboot) == -1)
930 		return;
931 	for (p = 0; p < MBR_PART_COUNT; p++) {
932 		printf("%*s%d: ", indent, "", p);
933 		print_mbr_partition(&eboot, p, start,
934 				    exoffset ? exoffset : start, indent);
935 	}
936 
937 	if (exoffset == 0)
938 		dumped = 1;
939 }
940 
941 /* Print a line with a label and a vis-encoded string */
942 static void
943 printvis(int indent, const char *label, const char *buf, size_t size)
944 {
945 	char *visbuf;
946 
947 	if ((visbuf = malloc(size * 4 + 1)) == NULL)
948 		err(1, "Malloc failed");
949 	strsvisx(visbuf, buf, size, VIS_TAB|VIS_NL|VIS_OCTAL, "\"");
950 	printf("%*s%s: \"%s\"\n",
951 	    indent, "",
952 	    label, visbuf);
953 	free(visbuf);
954 }
955 
956 /* Check whether a buffer contains all bytes zero */
957 static int
958 is_all_zero(const unsigned char *p, size_t size)
959 {
960 
961 	while (size-- > 0) {
962 		if (*p++ != 0)
963 			return 0;
964 	}
965 	return 1;
966 }
967 
968 /*
969  * Report on the contents of a PBR sector.
970  *
971  * We first perform several sanity checks.  If vflag >= 2, we report all
972  * failing tests, but for smaller values of v_flag we stop after the
973  * first failing test.  Tests are ordered in an attempt to get the most
974  * useful error message from the first failing test.
975  *
976  * If v_flag >= 2, we also report some decoded values from the PBR.
977  * These results may be meaningless, if the PBR doesn't follow common
978  * conventions.
979  *
980  * Trying to decode anything more than the magic number in the last
981  * two bytes is a layering violation, but it can be very useful in
982  * diagnosing boot failures.
983  */
984 static void
985 print_pbr(daddr_t sector, int indent, uint8_t part_type)
986 {
987 	struct mbr_sector pboot;
988 	unsigned char *p, *endp;
989 	unsigned char val;
990 	int ok;
991 	int errcount = 0;
992 
993 #define PBR_ERROR(...)							\
994 	do {								\
995 		++errcount;						\
996 		printf("%*s%s: ", indent, "",				\
997 		    (v_flag < 2 ? "PBR is not bootable" : "Not bootable")); \
998 		printf(__VA_ARGS__);					\
999 		if (v_flag < 2)						\
1000 			return;						\
1001 	} while (/*CONSTCOND*/ 0)
1002 
1003 	if (v_flag >= 2) {
1004 		printf("%*sInformation from PBR:\n",
1005 		    indent, "");
1006 		indent += 4;
1007 	}
1008 
1009 	if (read_disk(sector, &pboot) == -1) {
1010 		PBR_ERROR("Sector %"PRIdaddr" is unreadable (%s)\n",
1011 		    sector, strerror(errno));
1012 		return;
1013 	}
1014 
1015 	/* all bytes identical? */
1016 	p = (unsigned char *)&pboot;
1017 	endp = p + sizeof(pboot);
1018 	val = *p;
1019 	ok = 0;
1020 	for (; p < endp; p++) {
1021 		if (*p != val) {
1022 			ok = 1;
1023 			break;
1024 		}
1025 	}
1026 	if (! ok)
1027 		PBR_ERROR("All bytes are identical (0x%02x)\n", val);
1028 
1029 	if (pboot.mbr_magic != LE_MBR_MAGIC)
1030 		PBR_ERROR("Bad magic number (0x%04x)\n",
1031 			le16toh(pboot.mbr_magic));
1032 
1033 #if 0
1034 	/* Some i386 OS might fail this test.  All non-i386 will fail. */
1035 	if (pboot.mbr_jmpboot[0] != 0xE9
1036 	    && pboot.mbr_jmpboot[0] != 0xEB) {
1037 		PBR_ERROR("Does not begin with i386 JMP instruction"
1038 			" (0x%02x 0x%02x0 0x%02x)\n",
1039 		    pboot.mbr_jmpboot[0], pboot.mbr_jmpboot[1],
1040 		    pboot.mbr_jmpboot[2]);
1041 	}
1042 #endif
1043 
1044 	if (v_flag > 0 && errcount == 0)
1045 		printf("%*sPBR appears to be bootable\n",
1046 		    indent, "");
1047 	if (v_flag < 2)
1048 		return;
1049 
1050 	if (! is_all_zero(pboot.mbr_oemname, sizeof(pboot.mbr_oemname))) {
1051 		printvis(indent, "OEM name", (char *)pboot.mbr_oemname,
1052 			sizeof(pboot.mbr_oemname));
1053 	}
1054 
1055 	if (pboot.mbr_bpb.bpb16.bsBootSig == 0x29)
1056 		printf("%*sBPB FAT16 boot signature found\n",
1057 		    indent, "");
1058 	if (pboot.mbr_bpb.bpb32.bsBootSig == 0x29)
1059 		printf("%*sBPB FAT32 boot signature found\n",
1060 		    indent, "");
1061 
1062 #undef PBR_ERROR
1063 }
1064 
1065 static int
1066 read_boot(const char *name, void *buf, size_t len, int err_exit)
1067 {
1068 	int bfd, ret;
1069 	struct stat st;
1070 
1071 	if (boot_path != NULL)
1072 		free(boot_path);
1073 	if (strchr(name, '/') == 0)
1074 		asprintf(&boot_path, "%s/%s", boot_dir, name);
1075 	else
1076 		boot_path = strdup(name);
1077 	if (boot_path == NULL)
1078 		err(1, "Malloc failed");
1079 
1080 	if ((bfd = open(boot_path, O_RDONLY)) < 0 || fstat(bfd, &st) == -1) {
1081 		warn("%s", boot_path);
1082 		goto fail;
1083 	}
1084 
1085 	if (st.st_size > (off_t)len) {
1086 		warnx("%s: bootcode too large", boot_path);
1087 		goto fail;
1088 	}
1089 	ret = st.st_size;
1090 	if (ret < 0x200) {
1091 		warnx("%s: bootcode too small", boot_path);
1092 		goto fail;
1093 	}
1094 	if (read(bfd, buf, len) != ret) {
1095 		warn("%s", boot_path);
1096 		goto fail;
1097 	}
1098 
1099 	/*
1100 	 * Do some sanity checking here
1101 	 */
1102 	if (((struct mbr_sector *)buf)->mbr_magic != LE_MBR_MAGIC) {
1103 		warnx("%s: invalid magic", boot_path);
1104 		goto fail;
1105 	}
1106 
1107 	close(bfd);
1108 	ret = (ret + 0x1ff) & ~0x1ff;
1109 	return ret;
1110 
1111     fail:
1112 	if (bfd >= 0)
1113 		close(bfd);
1114 	if (err_exit)
1115 		exit(1);
1116 	return 0;
1117 }
1118 
1119 static void
1120 init_sector0(int zappart)
1121 {
1122 	int i;
1123 	int copy_size = offsetof(struct mbr_sector, mbr_dsn);
1124 
1125 #ifdef DEFAULT_BOOTCODE
1126 	if (bootsize == 0)
1127 		bootsize = read_boot(DEFAULT_BOOTCODE, bootcode,
1128 			sizeof bootcode, 0);
1129 #endif
1130 #ifdef BOOTSEL
1131 	if (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC
1132 	    && bootcode[0].mbr_bootsel_magic == LE_MBR_BS_MAGIC)
1133 		copy_size = MBR_BS_OFFSET;
1134 #endif
1135 
1136 	if (bootsize != 0) {
1137 		boot_installed = 1;
1138 		memcpy(&mboot, bootcode, copy_size);
1139 		mboot.mbr_bootsel_magic = bootcode[0].mbr_bootsel_magic;
1140 	}
1141 	mboot.mbr_magic = LE_MBR_MAGIC;
1142 
1143 	if (!zappart)
1144 		return;
1145 	for (i = 0; i < MBR_PART_COUNT; i++)
1146 		memset(&mboot.mbr_parts[i], 0, sizeof(mboot.mbr_parts[i]));
1147 }
1148 
1149 static void
1150 get_extended_ptn(void)
1151 {
1152 	struct mbr_partition *mp;
1153 	struct mbr_sector *boot;
1154 	daddr_t offset;
1155 	struct mbr_sector *nptn;
1156 
1157 	/* find first (there should only be one) extended partition */
1158 	for (mp = mboot.mbr_parts; !MBR_IS_EXTENDED(mp->mbrp_type); mp++)
1159 		if (mp >= &mboot.mbr_parts[MBR_PART_COUNT])
1160 			return;
1161 
1162 	/*
1163 	 * The extended partition should be structured as a linked list
1164 	 * (even though it appears, at first glance, to be a tree).
1165 	 */
1166 	ext.base = le32toh(mp->mbrp_start);
1167 	ext.limit = ext.base + le32toh(mp->mbrp_size);
1168 	ext.ptn_id = mp - mboot.mbr_parts;
1169 	for (offset = 0;; offset = le32toh(boot->mbr_parts[1].mbrp_start)) {
1170 		nptn = realloc(ext.ptn, (ext.num_ptn + 1) * sizeof *ext.ptn);
1171 		if (nptn == NULL)
1172 			err(1, "Malloc failed");
1173 		ext.ptn = nptn;
1174 		boot = ext.ptn + ext.num_ptn;
1175 		if (read_s0(offset + ext.base, boot) == -1)
1176 			break;
1177 		/* expect p0 to be valid and p1 to be another extended ptn */
1178 		if (MBR_IS_EXTENDED(boot->mbr_parts[0].mbrp_type))
1179 			break;
1180 		if (boot->mbr_parts[1].mbrp_type != 0 &&
1181 		    !MBR_IS_EXTENDED(boot->mbr_parts[1].mbrp_type))
1182 			break;
1183 		/* p2 and p3 should be unallocated */
1184 		if (boot->mbr_parts[2].mbrp_type != 0 ||
1185 		    boot->mbr_parts[3].mbrp_type != 0)
1186 			break;
1187 		/* data ptn inside extended one */
1188 		if (boot->mbr_parts[0].mbrp_type != 0 &&
1189 		    offset + le32toh(boot->mbr_parts[0].mbrp_start)
1190 		    + le32toh(boot->mbr_parts[0].mbrp_size) > ext.limit)
1191 			break;
1192 
1193 		ext.num_ptn++;
1194 
1195 		if (boot->mbr_parts[1].mbrp_type == 0)
1196 			/* end of extended partition chain */
1197 			return;
1198 		/* must be in sector order */
1199 		if (offset >= le32toh(boot->mbr_parts[1].mbrp_start))
1200 			break;
1201 	}
1202 
1203 	warnx("Extended partition table is corrupt\n");
1204 	ext.is_corrupt = 1;
1205 	ext.num_ptn = 0;
1206 }
1207 
1208 #if defined(USE_DISKLIST)
1209 static void
1210 get_diskname(const char *fullname, char *diskname, size_t size)
1211 {
1212 	const char *p, *p2;
1213 	size_t len;
1214 
1215 	p = strrchr(fullname, '/');
1216 	if (p == NULL)
1217 		p = fullname;
1218 	else
1219 		p++;
1220 
1221 	if (*p == 0) {
1222 		strlcpy(diskname, fullname, size);
1223 		return;
1224 	}
1225 
1226 	if (*p == 'r')
1227 		p++;
1228 
1229 	for (p2 = p; *p2 != 0; p2++)
1230 		if (isdigit((unsigned char)*p2))
1231 			break;
1232 	if (*p2 == 0) {
1233 		/* XXX invalid diskname? */
1234 		strlcpy(diskname, fullname, size);
1235 		return;
1236 	}
1237 	while (isdigit((unsigned char)*p2))
1238 		p2++;
1239 
1240 	len = p2 - p;
1241 	if (len > size) {
1242 		/* XXX */
1243 		strlcpy(diskname, fullname, size);
1244 		return;
1245 	}
1246 
1247 	memcpy(diskname, p, len);
1248 	diskname[len] = 0;
1249 }
1250 #endif
1251 
1252 static void
1253 get_ptn_alignmemt(void)
1254 {
1255 	struct mbr_partition *partp = &mboot.mbr_parts[0];
1256 	uint32_t ptn_0_base, ptn_0_limit;
1257 
1258 	/* Default to using 'traditional' cylinder alignment */
1259 	ptn_alignment = dos_cylindersectors;
1260 	ptn_0_offset = dos_sectors;
1261 
1262 	if (partp->mbrp_type != 0) {
1263 		/* Try to copy alignment of first partition */
1264 		ptn_0_base = le32toh(partp->mbrp_start);
1265 		ptn_0_limit = ptn_0_base + le32toh(partp->mbrp_size);
1266 		if (!(ptn_0_limit & 2047)) {
1267 			/* Partition ends on a 1MB boundary, align to 1MB */
1268 			ptn_alignment = 2048;
1269 			if (ptn_0_base <= 2048
1270 			    && !(ptn_0_base & (ptn_0_base - 1))) {
1271 				/* ptn_base is a power of 2, use it */
1272 				ptn_0_offset = ptn_0_base;
1273 			}
1274 		}
1275 	} else {
1276 		/* Use 1MB alignment for large disks */
1277 		if (disksectors > 2048 * 1024 * 128) {
1278 			ptn_alignment = 2048;
1279 			ptn_0_offset = 2048;
1280 		}
1281 	}
1282 }
1283 
1284 static void
1285 get_bios_geometry(void)
1286 {
1287 #if defined(USE_DISKLIST)
1288 	int mib[2], i;
1289 	size_t len;
1290 	struct biosdisk_info *bip;
1291 	struct nativedisk_info *nip;
1292 	char diskname[8];
1293 
1294 	mib[0] = CTL_MACHDEP;
1295 	mib[1] = CPU_DISKINFO;
1296 	if (sysctl(mib, 2, NULL, &len, NULL, 0) < 0) {
1297 		goto out;
1298 	}
1299 	dl = (struct disklist *) malloc(len);
1300 	if (dl == NULL)
1301 		err(1, "Malloc failed");
1302 	if (sysctl(mib, 2, dl, &len, NULL, 0) < 0) {
1303 		free(dl);
1304 		dl = 0;
1305 		goto out;
1306 	}
1307 
1308 	get_diskname(disk, diskname, sizeof diskname);
1309 
1310 	for (i = 0; i < dl->dl_nnativedisks; i++) {
1311 		nip = &dl->dl_nativedisks[i];
1312 		if (strcmp(diskname, nip->ni_devname))
1313 			continue;
1314 		/*
1315 		 * XXX listing possible matches is better. This is ok for
1316 		 * now because the user has a chance to change it later.
1317 		 * Also, if all the disks have the same parameters then we can
1318 		 * just use them, we don't need to know which disk is which.
1319 		 */
1320 		if (nip->ni_nmatches != 0) {
1321 			bip = &dl->dl_biosdisks[nip->ni_biosmatches[0]];
1322 			dos_cylinders = bip->bi_cyl;
1323 			dos_heads = bip->bi_head;
1324 			dos_sectors = bip->bi_sec;
1325 			if (bip->bi_lbasecs)
1326 				dos_disksectors = bip->bi_lbasecs;
1327 			return;
1328 		}
1329 	}
1330  out:
1331 #endif
1332 	/* Allright, allright, make a stupid guess.. */
1333 	intuit_translated_geometry();
1334 }
1335 
1336 #ifdef BOOTSEL
1337 static daddr_t
1338 get_default_boot(void)
1339 {
1340 	unsigned int id;
1341 	int p;
1342 
1343 	if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1344 		/* default to first active partition */
1345 		return DEFAULT_ACTIVE;
1346 
1347 	id = mboot.mbr_bootsel.mbrbs_defkey;
1348 
1349 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ASCII) {
1350 		/* Keycode is ascii */
1351 		if (id == '\r')
1352 		    return DEFAULT_ACTIVE;
1353 		/* '1'+ => allocated partition id, 'a'+ => disk 0+ */
1354 		if (id >= 'a' && id < 'a' + MAX_BIOS_DISKS)
1355 			return DEFAULT_DISK(id - 'a');
1356 		id -= '1';
1357 	} else {
1358 		/* keycode is PS/2 keycode */
1359 		if (id == SCAN_ENTER)
1360 			return DEFAULT_ACTIVE;
1361 		/* 1+ => allocated partition id, F1+ => disk 0+ */
1362 		if (id >= SCAN_F1 && id < SCAN_F1 + MAX_BIOS_DISKS)
1363 			return DEFAULT_DISK(id - SCAN_F1);
1364 		id -= SCAN_1;
1365 	}
1366 
1367 	/* Convert partition index to the invariant start sector number */
1368 
1369 	for (p = 0; p < MBR_PART_COUNT; p++) {
1370 		if (mboot.mbr_parts[p].mbrp_type == 0)
1371 			continue;
1372 		if (mboot.mbr_bootsel.mbrbs_nametab[p][0] == 0)
1373 			continue;
1374 		if (id-- == 0)
1375 			return le32toh(mboot.mbr_parts[p].mbrp_start);
1376 	}
1377 
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 (id-- == 0)
1384 			return ext_offset(p)
1385 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start);
1386 	}
1387 
1388 	return DEFAULT_ACTIVE;
1389 }
1390 
1391 static void
1392 set_default_boot(daddr_t default_ptn)
1393 {
1394 	int p;
1395 	static const unsigned char key_list[] = { SCAN_ENTER, SCAN_F1, SCAN_1,
1396 						'\r', 'a', '1' };
1397 	const unsigned char *key = key_list;
1398 
1399 	if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1400 		/* sanity */
1401 		return;
1402 
1403 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ASCII)
1404 		/* Use ascii values */
1405 		key += 3;
1406 
1407 	if (default_ptn == DEFAULT_ACTIVE) {
1408 		mboot.mbr_bootsel.mbrbs_defkey = key[0];
1409 		return;
1410 	}
1411 
1412 	if (default_ptn >= DEFAULT_DISK(0)
1413 	    && default_ptn < DEFAULT_DISK(MAX_BIOS_DISKS)) {
1414 		mboot.mbr_bootsel.mbrbs_defkey = key[1]
1415 		    + default_ptn - DEFAULT_DISK(0);
1416 		return;
1417 	}
1418 
1419 	mboot.mbr_bootsel.mbrbs_defkey = key[2];
1420 	for (p = 0; p < MBR_PART_COUNT; p++) {
1421 		if (mboot.mbr_parts[p].mbrp_type == 0)
1422 			continue;
1423 		if (mboot.mbr_bootsel.mbrbs_nametab[p][0] == 0)
1424 			continue;
1425 		if (le32toh(mboot.mbr_parts[p].mbrp_start) == default_ptn)
1426 			return;
1427 		mboot.mbr_bootsel.mbrbs_defkey++;
1428 	}
1429 
1430 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_EXTLBA) {
1431 		for (p = 0; p < ext.num_ptn; p++) {
1432 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1433 				continue;
1434 			if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1435 				continue;
1436 			if (le32toh(ext.ptn[p].mbr_parts[0].mbrp_start) +
1437 			    ext_offset(p) == default_ptn)
1438 				return;
1439 			mboot.mbr_bootsel.mbrbs_defkey++;
1440 		}
1441 	}
1442 
1443 	/* Default to first active partition */
1444 	mboot.mbr_bootsel.mbrbs_defkey = key[0];
1445 }
1446 
1447 static void
1448 install_bootsel(int needed)
1449 {
1450 	struct mbr_bootsel *mbs = &mboot.mbr_bootsel;
1451 	int p;
1452 	int ext13 = 0;
1453 	const char *code;
1454 
1455 	needed |= MBR_BS_NEWMBR;	/* need new bootsel code */
1456 
1457 	/* Work out which boot code we need for this configuration */
1458 	for (p = 0; p < MBR_PART_COUNT; p++) {
1459 		if (mboot.mbr_parts[p].mbrp_type == 0)
1460 			continue;
1461 		if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1462 			break;
1463 		if (mbs->mbrbs_nametab[p][0] == 0)
1464 			continue;
1465 		needed |= MBR_BS_ACTIVE;
1466 		if (le32toh(mboot.mbr_parts[p].mbrp_start) >= dos_totalsectors)
1467 			ext13 = MBR_BS_EXTINT13;
1468 	}
1469 
1470 	for (p = 0; p < ext.num_ptn; p++) {
1471 		if (ext.ptn[p].mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1472 			continue;
1473 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1474 			continue;
1475 		if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[p][0] == 0)
1476 			continue;
1477 		needed |= MBR_BS_EXTLBA | MBR_BS_ACTIVE;
1478 	}
1479 
1480 	if (B_flag)
1481 		needed |= MBR_BS_ACTIVE;
1482 
1483 	/* Is the installed code good enough ? */
1484 	if (!i_flag && (needed == 0 ||
1485 	    (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC
1486 	    && (mbs->mbrbs_flags & needed) == needed))) {
1487 		/* yes - just set flags */
1488 		mbs->mbrbs_flags |= ext13;
1489 		return;
1490 	}
1491 
1492 	/* ok - we need to replace the bootcode */
1493 
1494 	if (f_flag && !(i_flag || B_flag)) {
1495 		warnx("Installed bootfile doesn't support required options.");
1496 		return;
1497 	}
1498 
1499 	if (!f_flag && bootsize == 0 && !i_flag)
1500 		/* Output an explanation for the 'update bootcode' prompt. */
1501 		printf("\n%s\n",
1502 		    "Installed bootfile doesn't support required options.");
1503 
1504 	/* Were we told a specific file ? (which we have already read) */
1505 	/* If so check that it supports what we need. */
1506 	if (bootsize != 0 && needed != 0
1507 	    && (bootcode[0].mbr_bootsel_magic != LE_MBR_BS_MAGIC
1508 	    || ((bootcode[0].mbr_bootsel.mbrbs_flags & needed) != needed))) {
1509 		/* No it doesn't... */
1510 		if (f_flag)
1511 			warnx("Bootfile %s doesn't support "
1512 				    "required bootsel options", boot_path );
1513 			/* But install it anyway */
1514 		else
1515 			if (yesno("Bootfile %s doesn't support the required "
1516 			    "options,\ninstall default bootfile instead?",
1517 			    boot_path))
1518 				bootsize = 0;
1519 	}
1520 
1521 	if (bootsize == 0) {
1522 		/* Get name of bootfile that supports the required facilities */
1523 		code = DEFAULT_BOOTCODE;
1524 		if (needed & MBR_BS_ACTIVE)
1525 			code = DEFAULT_BOOTSELCODE;
1526 #ifdef DEFAULT_BOOTEXTCODE
1527 		if (needed & MBR_BS_EXTLBA)
1528 			code = DEFAULT_BOOTEXTCODE;
1529 #endif
1530 
1531 		bootsize = read_boot(code, bootcode, sizeof bootcode, 0);
1532 		if (bootsize == 0)
1533 			/* The old bootcode is better than no bootcode at all */
1534 			return;
1535 		if ((bootcode[0].mbr_bootsel.mbrbs_flags & needed) != needed)
1536 			warnx("Default bootfile %s doesn't support required "
1537 				"options.  Got flags 0x%x, wanted 0x%x\n",
1538 				boot_path, bootcode[0].mbr_bootsel.mbrbs_flags,
1539 				needed);
1540 	}
1541 
1542 	if (!f_flag && !yesno("Update the bootcode from %s?", boot_path))
1543 		return;
1544 
1545 	init_sector0(0);
1546 
1547 	if (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC)
1548 		mbs->mbrbs_flags = bootcode[0].mbr_bootsel.mbrbs_flags | ext13;
1549 }
1550 
1551 static daddr_t
1552 configure_bootsel(daddr_t default_ptn)
1553 {
1554 	struct mbr_bootsel *mbs = &mboot.mbr_bootsel;
1555 	int i, item, opt;
1556 	int tmo;
1557 	daddr_t *off;
1558 	int num_bios_disks;
1559 
1560 #if defined(USE_DISKLIST)
1561 	if (dl != NULL) {
1562 		num_bios_disks = dl->dl_nbiosdisks;
1563 		if (num_bios_disks > MAX_BIOS_DISKS)
1564 			num_bios_disks = MAX_BIOS_DISKS;
1565 	} else
1566 #endif
1567 		num_bios_disks = MAX_BIOS_DISKS;
1568 
1569 	printf("\nBoot selector configuration:\n");
1570 
1571 	/* The timeout value is in ticks, ~18.2 Hz. Avoid using floats.
1572 	 * Ticks are nearly 64k/3600 - so our long timers are sligtly out!
1573 	 * Newer bootcode always waits for 1 tick, so treats 0xffff
1574 	 * as wait forever.
1575 	 */
1576 	tmo = le16toh(mbs->mbrbs_timeo);
1577 	tmo = tmo == 0xffff ? -1 : (10 * tmo + 9) / 182;
1578 	tmo = decimal("Timeout value (0 to 3600 seconds, -1 => never)",
1579 			tmo, 0, -1, 3600);
1580 	mbs->mbrbs_timeo = htole16(tmo == -1 ? 0xffff : (tmo * 182) / 10);
1581 
1582 	off = calloc(1 + MBR_PART_COUNT + ext.num_ptn + num_bios_disks, sizeof *off);
1583 	if (off == NULL)
1584 		err(1, "Malloc failed");
1585 
1586 	printf("Select the default boot option. Options are:\n\n");
1587 	item = 0;
1588 	opt = 0;
1589 	off[opt] = DEFAULT_ACTIVE;
1590 	printf("%d: The first active partition\n", opt);
1591 	for (i = 0; i < MBR_PART_COUNT; i++) {
1592 		if (mboot.mbr_parts[i].mbrp_type == 0)
1593 			continue;
1594 		if (mbs->mbrbs_nametab[i][0] == 0)
1595 			continue;
1596 		printf("%d: %s\n", ++opt, &mbs->mbrbs_nametab[i][0]);
1597 		off[opt] = le32toh(mboot.mbr_parts[i].mbrp_start);
1598 		if (off[opt] == default_ptn)
1599 			item = opt;
1600 	}
1601 	if (mbs->mbrbs_flags & MBR_BS_EXTLBA) {
1602 		for (i = 0; i < ext.num_ptn; i++) {
1603 			if (ext.ptn[i].mbr_parts[0].mbrp_type == 0)
1604 				continue;
1605 			if (ext.ptn[i].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1606 				continue;
1607 			printf("%d: %s\n",
1608 			    ++opt, ext.ptn[i].mbr_bootsel.mbrbs_nametab[0]);
1609 			off[opt] = ext_offset(i) +
1610 			    le32toh(ext.ptn[i].mbr_parts[0].mbrp_start);
1611 			if (off[opt] == default_ptn)
1612 				item = opt;
1613 		}
1614 	}
1615 	for (i = 0; i < num_bios_disks; i++) {
1616 		printf("%d: Harddisk %d\n", ++opt, i);
1617 		off[opt] = DEFAULT_DISK(i);
1618 		if (DEFAULT_DISK(i) == default_ptn)
1619 			item = opt;
1620 	}
1621 
1622 	item = decimal("Default boot option", item, 0, 0, opt);
1623 
1624 	default_ptn = off[item];
1625 	free(off);
1626 	return default_ptn;
1627 }
1628 #endif /* BOOTSEL */
1629 
1630 
1631 /* Prerequisite: the disklabel parameters and master boot record must
1632  *		 have been read (i.e. dos_* and mboot are meaningful).
1633  * Specification: modifies dos_cylinders, dos_heads, dos_sectors, and
1634  *		  dos_cylindersectors to be consistent with what the
1635  *		  partition table is using, if we can find a geometry
1636  *		  which is consistent with all partition table entries.
1637  *		  We may get the number of cylinders slightly wrong (in
1638  *		  the conservative direction).  The idea is to be able
1639  *		  to create a NetBSD partition on a disk we don't know
1640  *		  the translated geometry of.
1641  * This routine is only used for non-x86 systems or when we fail to
1642  * get the BIOS geometry from the kernel.
1643  */
1644 static void
1645 intuit_translated_geometry(void)
1646 {
1647 	uint32_t xcylinders;
1648 	int xheads = -1, xsectors = -1, i, j;
1649 	unsigned int c1, h1, s1, c2, h2, s2;
1650 	unsigned long a1, a2;
1651 	uint64_t num, denom;
1652 
1653 	/*
1654 	 * The physical parameters may be invalid as bios geometry.
1655 	 * If we cannot determine the actual bios geometry, we are
1656 	 * better off picking a likely 'faked' geometry than leaving
1657 	 * the invalid physical one.
1658 	 */
1659 
1660 	if (dos_cylinders > MAXCYL || dos_heads > MAXHEAD ||
1661 	    dos_sectors > MAXSECTOR) {
1662 		h1 = MAXHEAD - 1;
1663 		c1 = MAXCYL - 1;
1664 #if defined(USE_DISKLIST)
1665 		if (dl != NULL) {
1666 			/* BIOS may use 256 heads or 1024 cylinders */
1667 			for (i = 0; i < dl->dl_nbiosdisks; i++) {
1668 				if (h1 < (unsigned int)dl->dl_biosdisks[i].bi_head)
1669 					h1 = dl->dl_biosdisks[i].bi_head;
1670 				if (c1 < (unsigned int)dl->dl_biosdisks[i].bi_cyl)
1671 					c1 = dl->dl_biosdisks[i].bi_cyl;
1672 			}
1673 		}
1674 #endif
1675 		dos_sectors = MAXSECTOR;
1676 		dos_heads = h1;
1677 		dos_cylinders = disklabel.d_secperunit / (MAXSECTOR * h1);
1678 		if (dos_cylinders > c1)
1679 			dos_cylinders = c1;
1680 	}
1681 
1682 	/* Try to deduce the number of heads from two different mappings. */
1683 	for (i = 0; i < MBR_PART_COUNT * 2 - 1; i++) {
1684 		if (get_mapping(i, &c1, &h1, &s1, &a1) < 0)
1685 			continue;
1686 		a1 -= s1;
1687 		for (j = i + 1; j < MBR_PART_COUNT * 2; j++) {
1688 			if (get_mapping(j, &c2, &h2, &s2, &a2) < 0)
1689 				continue;
1690 			a2 -= s2;
1691 			num = (uint64_t)h1 * a2 - (uint64_t)h2 * a1;
1692 			denom = (uint64_t)c2 * a1 - (uint64_t)c1 * a2;
1693 			if (denom != 0 && num != 0 && num % denom == 0) {
1694 				xheads = num / denom;
1695 				xsectors = a1 / (c1 * xheads + h1);
1696 				break;
1697 			}
1698 		}
1699 		if (xheads != -1)
1700 			break;
1701 	}
1702 
1703 	if (xheads == -1) {
1704 		if (F_flag)
1705 			return;
1706 		warnx("Cannot determine the number of heads");
1707 		return;
1708 	}
1709 
1710 	if (xsectors == -1) {
1711 		warnx("Cannot determine the number of sectors");
1712 		return;
1713 	}
1714 
1715 	/* Estimate the number of cylinders. */
1716 	xcylinders = disklabel.d_secperunit / xheads / xsectors;
1717 	if (disklabel.d_secperunit > xcylinders * xheads * xsectors)
1718 		xcylinders++;
1719 
1720 	/*
1721 	 * Now verify consistency with each of the partition table entries.
1722 	 * Be willing to shove cylinders up a little bit to make things work,
1723 	 * but translation mismatches are fatal.
1724 	 */
1725 	for (i = 0; i < MBR_PART_COUNT * 2; i++) {
1726 		if (get_mapping(i, &c1, &h1, &s1, &a1) < 0)
1727 			continue;
1728 		if (c1 >= MAXCYL - 2)
1729 			continue;
1730 		if (xsectors * (c1 * xheads + h1) + s1 != a1)
1731 			return;
1732 	}
1733 
1734 
1735 	/* Everything checks out.
1736 	 * Reset the geometry to use for further calculations.
1737 	 * But cylinders cannot be > 1024.
1738 	 */
1739 	if (xcylinders > MAXCYL)
1740 		dos_cylinders = MAXCYL;
1741 	else
1742 		dos_cylinders = xcylinders;
1743 	dos_heads = xheads;
1744 	dos_sectors = xsectors;
1745 }
1746 
1747 /*
1748  * For the purposes of intuit_translated_geometry(), treat the partition
1749  * table as a list of eight mapping between (cylinder, head, sector)
1750  * triplets and absolute sectors.  Get the relevant geometry triplet and
1751  * absolute sectors for a given entry, or return -1 if it isn't present.
1752  * Note: for simplicity, the returned sector is 0-based.
1753  */
1754 static int
1755 get_mapping(int i, unsigned int *cylinder, unsigned int *head, unsigned int *sector,
1756     unsigned long *absolute)
1757 {
1758 	struct mbr_partition *part = &mboot.mbr_parts[i / 2];
1759 
1760 	if (part->mbrp_type == 0)
1761 		return -1;
1762 	if (i % 2 == 0) {
1763 		*cylinder = MBR_PCYL(part->mbrp_scyl, part->mbrp_ssect);
1764 		*head = part->mbrp_shd;
1765 		*sector = MBR_PSECT(part->mbrp_ssect);
1766 		*absolute = le32toh(part->mbrp_start);
1767 	} else {
1768 		*cylinder = MBR_PCYL(part->mbrp_ecyl, part->mbrp_esect);
1769 		*head = part->mbrp_ehd;
1770 		*sector = MBR_PSECT(part->mbrp_esect);
1771 		*absolute = le32toh(part->mbrp_start)
1772 		    + le32toh(part->mbrp_size) - 1;
1773 	}
1774 	/* Sanity check the data against all zeroes */
1775 	if ((*cylinder == 0) && (*sector == 0) && (*head == 0))
1776 		return -1;
1777 	/* sector numbers in the MBR partition table start at 1 */
1778 	*sector = *sector - 1;
1779 	/* Sanity check the data against max values */
1780 	if ((((*cylinder * MAXHEAD) + *head) * MAXSECTOR + *sector) < *absolute)
1781 		/* cannot be a CHS mapping */
1782 		return -1;
1783 	return 0;
1784 }
1785 
1786 static void
1787 delete_ptn(int part)
1788 {
1789 	if (part == ext.ptn_id) {
1790 		/* forget all about the extended partition */
1791 		free(ext.ptn);
1792 		memset(&ext, 0, sizeof ext);
1793 	}
1794 
1795 	mboot.mbr_parts[part].mbrp_type = 0;
1796 }
1797 
1798 static void
1799 delete_ext_ptn(int part)
1800 {
1801 
1802 	if (part == 0) {
1803 		ext.ptn[0].mbr_parts[0].mbrp_type = 0;
1804 		return;
1805 	}
1806 	ext.ptn[part - 1].mbr_parts[1] = ext.ptn[part].mbr_parts[1];
1807 	memmove(&ext.ptn[part], &ext.ptn[part + 1],
1808 		(ext.num_ptn - part - 1) * sizeof ext.ptn[0]);
1809 	ext.num_ptn--;
1810 }
1811 
1812 static int
1813 add_ext_ptn(daddr_t start, daddr_t size)
1814 {
1815 	int part;
1816 	struct mbr_partition *partp;
1817 	struct mbr_sector *nptn;
1818 
1819 	nptn = realloc(ext.ptn, (ext.num_ptn + 1) * sizeof *ext.ptn);
1820 	if (!nptn)
1821 		err(1, "realloc");
1822 	ext.ptn = nptn;
1823 	for (part = 0; part < ext.num_ptn; part++)
1824 		if (ext_offset(part) > start)
1825 			break;
1826 	/* insert before 'part' - make space... */
1827 	memmove(&ext.ptn[part + 1], &ext.ptn[part],
1828 		(ext.num_ptn - part) * sizeof ext.ptn[0]);
1829 	memset(&ext.ptn[part], 0, sizeof ext.ptn[0]);
1830 	ext.ptn[part].mbr_magic = LE_MBR_MAGIC;
1831 	/* we will be 'part' */
1832 	if (part == 0) {
1833 		/* link us to 'next' */
1834 		partp = &ext.ptn[0].mbr_parts[1];
1835 		/* offset will be fixed by caller */
1836 		partp->mbrp_size = htole32(
1837 		    le32toh(ext.ptn[1].mbr_parts[0].mbrp_start) +
1838 		    le32toh(ext.ptn[1].mbr_parts[0].mbrp_size));
1839 	} else {
1840 		/* link us to prev's next */
1841 		partp = &ext.ptn[part - 1].mbr_parts[1];
1842 		ext.ptn[part].mbr_parts[1] = *partp;
1843 		/* and prev onto us */
1844 		partp->mbrp_start = htole32(start - ptn_0_offset - ext.base);
1845 		partp->mbrp_size = htole32(size + ptn_0_offset);
1846 	}
1847 	partp->mbrp_type = 5;	/* as used by win98 */
1848 	partp->mbrp_flag = 0;
1849 	/* wallop in some CHS values - win98 doesn't saturate them */
1850 	dos(le32toh(partp->mbrp_start),
1851 	    &partp->mbrp_scyl, &partp->mbrp_shd, &partp->mbrp_ssect);
1852 	dos(le32toh(partp->mbrp_start) + le32toh(partp->mbrp_size) - 1,
1853 	    &partp->mbrp_ecyl, &partp->mbrp_ehd, &partp->mbrp_esect);
1854 	ext.num_ptn++;
1855 
1856 	return part;
1857 }
1858 
1859 static const char *
1860 check_overlap(int part, int sysid, daddr_t start, daddr_t size, int fix)
1861 {
1862 	int p;
1863 	unsigned int p_s, p_e;
1864 
1865 	if (sysid != 0) {
1866 		if (start == 0)
1867 			return "Sector zero is reserved for the MBR";
1868 #if 0
1869 		if (start < ptn_0_offset)
1870 			/* This is just a convention, not a requirement */
1871 			return "Track zero is reserved for the BIOS";
1872 #endif
1873 		if (start + size > disksectors)
1874 			return "Partition exceeds size of disk";
1875 		for (p = 0; p < MBR_PART_COUNT; p++) {
1876 			if (p == part || mboot.mbr_parts[p].mbrp_type == 0)
1877 				continue;
1878 			p_s = le32toh(mboot.mbr_parts[p].mbrp_start);
1879 			p_e = p_s + le32toh(mboot.mbr_parts[p].mbrp_size);
1880 			if (start + size <= p_s || start >= p_e)
1881 				continue;
1882 			if (f_flag) {
1883 				if (fix)
1884 					delete_ptn(p);
1885 				return 0;
1886 			}
1887 			return "Overlaps another partition";
1888 		}
1889 	}
1890 
1891 	/* Are we trying to create an extended partition */
1892 	if (!MBR_IS_EXTENDED(mboot.mbr_parts[part].mbrp_type)) {
1893 		/* this wasn't the extended partition */
1894 		if (!MBR_IS_EXTENDED(sysid))
1895 			return 0;
1896 		/* making an extended partition */
1897 		if (ext.base != 0) {
1898 			if (!f_flag)
1899 				return "There cannot be 2 extended partitions";
1900 			if (fix)
1901 				delete_ptn(ext.ptn_id);
1902 		}
1903 		if (fix) {
1904 			/* allocate a new extended partition */
1905 			ext.ptn = calloc(1, sizeof ext.ptn[0]);
1906 			if (ext.ptn == NULL)
1907 				err(1, "Malloc failed");
1908 			ext.ptn[0].mbr_magic = LE_MBR_MAGIC;
1909 			ext.ptn_id = part;
1910 			ext.base = start;
1911 			ext.limit = start + size;
1912 			ext.num_ptn = 1;
1913 		}
1914 		return 0;
1915 	}
1916 
1917 	/* Check we haven't cut space allocated to an extended ptn */
1918 
1919 	if (!MBR_IS_EXTENDED(sysid)) {
1920 		/* no longer an extended partition */
1921 		if (fix) {
1922 			/* Kill all memory of the extended partitions */
1923 			delete_ptn(part);
1924 			return 0;
1925 		}
1926 		if (ext.num_ptn == 0 ||
1927 		    (ext.num_ptn == 1 && ext.ptn[0].mbr_parts[0].mbrp_type == 0))
1928 			/* nothing in extended partition */
1929 			return 0;
1930 		if (f_flag)
1931 			return 0;
1932 		if (yesno("Do you really want to delete all the extended partitions?"))
1933 			return 0;
1934 		return "Extended partition busy";
1935 	}
1936 
1937 	if (le32toh(mboot.mbr_parts[part].mbrp_start) != ext.base)
1938 		/* maybe impossible, but an extra sanity check */
1939 		return 0;
1940 
1941 	for (p = ext.num_ptn; --p >= 0;) {
1942 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1943 			continue;
1944 		p_s = ext_offset(p);
1945 		p_e = p_s + le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
1946 			  + le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
1947 		if (p_s >= start && p_e <= start + size)
1948 			continue;
1949 		if (!f_flag)
1950 			return "Extended partition outside main partition";
1951 		if (fix)
1952 			delete_ext_ptn(p);
1953 	}
1954 
1955 	if (fix && start != ext.base) {
1956 		/* The internal offsets need to be fixed up */
1957 		for (p = 0; p < ext.num_ptn - 1; p++)
1958 			ext.ptn[p].mbr_parts[1].mbrp_start = htole32(
1959 			    le32toh(ext.ptn[p].mbr_parts[1].mbrp_start)
1960 				    + ext.base - start);
1961 		/* and maybe an empty partition at the start */
1962 		if (ext.ptn[0].mbr_parts[0].mbrp_type == 0) {
1963 			if (le32toh(ext.ptn[0].mbr_parts[1].mbrp_start) == 0) {
1964 				/* don't need the empty slot */
1965 				memmove(&ext.ptn[0], &ext.ptn[1],
1966 					(ext.num_ptn - 1) * sizeof ext.ptn[0]);
1967 				ext.num_ptn--;
1968 			}
1969 		} else {
1970 			/* must create an empty slot */
1971 			add_ext_ptn(start, ptn_0_offset);
1972 			ext.ptn[0].mbr_parts[1].mbrp_start = htole32(ext.base
1973 								- start);
1974 		}
1975 	}
1976 	if (fix) {
1977 		ext.base = start;
1978 		ext.limit = start + size;
1979 	}
1980 	return 0;
1981 }
1982 
1983 static const char *
1984 check_ext_overlap(int part, int sysid, daddr_t start, daddr_t size, int fix)
1985 {
1986 	int p;
1987 	unsigned int p_s, p_e;
1988 
1989 	if (sysid == 0)
1990 		return 0;
1991 
1992 	if (MBR_IS_EXTENDED(sysid))
1993 		return "Nested extended partitions are not allowed";
1994 
1995 	/* allow one track at start for extended partition header */
1996 	start -= ptn_0_offset;
1997 	size += ptn_0_offset;
1998 	if (start < ext.base || start + size > ext.limit)
1999 		return "Outside bounds of extended partition";
2000 
2001 	if (f_flag && !fix)
2002 		return 0;
2003 
2004 	for (p = ext.num_ptn; --p >= 0;) {
2005 		if (p == part || ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2006 			continue;
2007 		p_s = ext_offset(p);
2008 		p_e = p_s + le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2009 			+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
2010 		if (p == 0)
2011 			p_s += le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2012 							- ptn_0_offset;
2013 		if (start < p_e && start + size > p_s) {
2014 			if (!f_flag)
2015 				return "Overlaps another extended partition";
2016 			if (fix) {
2017 				if (part == -1)
2018 					delete_ext_ptn(p);
2019 				else
2020 					/* must not change numbering yet */
2021 					ext.ptn[p].mbr_parts[0].mbrp_type = 0;
2022 			}
2023 		}
2024 	}
2025 	return 0;
2026 }
2027 
2028 static int
2029 change_part(int extended, int part, int sysid, daddr_t start, daddr_t size,
2030 	char *bootmenu)
2031 {
2032 	struct mbr_partition *partp;
2033 	struct mbr_sector *boot;
2034 	daddr_t offset;
2035 	const char *e;
2036 	int upart = part;
2037 	int p;
2038 	int fl;
2039 	daddr_t n_s, n_e;
2040 	const char *errtext;
2041 #ifdef BOOTSEL
2042 	char tmp_bootmenu[MBR_PART_COUNT * (MBR_BS_PARTNAMESIZE + 1)];
2043 	int bootmenu_len = (extended ? MBR_PART_COUNT : 1) * (MBR_BS_PARTNAMESIZE + 1);
2044 #endif
2045 
2046 	if (extended) {
2047 		if (part != -1 && part < ext.num_ptn) {
2048 			boot = &ext.ptn[part];
2049 			partp = &boot->mbr_parts[0];
2050 			offset = ext_offset(part);
2051 		} else {
2052 			part = -1;
2053 			boot = 0;
2054 			partp = 0;
2055 			offset = 0;
2056 		}
2057 		upart = 0;
2058 		e = "E";
2059 	} else {
2060 		boot = &mboot;
2061 		partp = &boot->mbr_parts[part];
2062 		offset = 0;
2063 		e = "";
2064 	}
2065 
2066 	if (!f_flag && part != -1) {
2067 		printf("The data for partition %s%d is:\n", e, part);
2068 		print_part(boot, upart, offset);
2069 	}
2070 
2071 #ifdef BOOTSEL
2072 	if (bootmenu != NULL)
2073 		strlcpy(tmp_bootmenu, bootmenu, bootmenu_len);
2074 	else
2075 		if (boot != NULL && boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC)
2076 			strlcpy(tmp_bootmenu,
2077 				boot->mbr_bootsel.mbrbs_nametab[upart],
2078 				bootmenu_len);
2079 		else
2080 			tmp_bootmenu[0] = 0;
2081 #endif
2082 
2083 	if (partp != NULL) {
2084 		if (!s_flag) {
2085 			/* values not specified, default to current ones */
2086 			sysid = partp->mbrp_type;
2087 			start = offset + le32toh(partp->mbrp_start);
2088 			size = le32toh(partp->mbrp_size);
2089 		} else {
2090 			if (sysid == -1)
2091 				sysid = partp->mbrp_type;
2092 			if (start == (daddr_t)0xffffffff) {
2093 				start = offset + le32toh(partp->mbrp_start);
2094 				if (start == 0)
2095 					start = offset = ptn_0_offset;
2096 			}
2097 			if (size == (daddr_t)0xffffffff) {
2098 				size = le32toh(partp->mbrp_size);
2099 				if (size == 0)
2100 					size = disksectors - start;
2101 			}
2102 		}
2103 	}
2104 
2105 	/* creating a new partition, default to free space */
2106 	if (!s_flag && sysid == 0 && extended) {
2107 		/* non-extended partition */
2108 		start = ext.base;
2109 		for (p = 0; p < ext.num_ptn; p++) {
2110 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2111 				continue;
2112 			n_s = ext_offset(p);
2113 			if (n_s > start + ptn_0_offset)
2114 				break;
2115 			start = ext_offset(p)
2116 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2117 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
2118 		}
2119 		if (ext.limit - start <= ptn_0_offset) {
2120 			printf("No space in extended partition\n");
2121 			return 0;
2122 		}
2123 		start += ptn_0_offset;
2124 	}
2125 
2126 	if (!s_flag && sysid == 0 && !extended) {
2127 		/* same for non-extended partition */
2128 		/* first see if old start is free */
2129 		if (start < ptn_0_offset)
2130 			start = 0;
2131 		for (p = 0; start != 0 && p < MBR_PART_COUNT; p++) {
2132 			if (mboot.mbr_parts[p].mbrp_type == 0)
2133 				continue;
2134 			n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2135 			if (start >= n_s &&
2136 			    start < n_s + le32toh(mboot.mbr_parts[p].mbrp_size))
2137 				start = 0;
2138 		}
2139 		if (start == 0) {
2140 			/* Look for first gap */
2141 			start = ptn_0_offset;
2142 			for (p = 0; p < MBR_PART_COUNT; p++) {
2143 				if (mboot.mbr_parts[p].mbrp_type == 0)
2144 					continue;
2145 				n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2146 				n_e = n_s + le32toh(mboot.mbr_parts[p].mbrp_size);
2147 				if (start >= n_s && start < n_e) {
2148 					start = n_e;
2149 					p = -1;
2150 				}
2151 			}
2152 			if (start >= disksectors && !I_flag) {
2153 				printf("No free space\n");
2154 				return 0;
2155 			}
2156 		}
2157 	}
2158 
2159 	if (!f_flag) {
2160 		/* request new values from user */
2161 		if (sysid == 0)
2162 			sysid = 169;
2163 		sysid = decimal("sysid", sysid, 0, 0, 255);
2164 		if (sysid == 0 && !v_flag) {
2165 			start = 0;
2166 			size = 0;
2167 #ifdef BOOTSEL
2168 			tmp_bootmenu[0] = 0;
2169 #endif
2170 		} else {
2171 			daddr_t old = start;
2172 			daddr_t lim = extended ? ext.limit : disksectors;
2173 			start = decimal("start", start,
2174 				DEC_SEC | DEC_RND_0 | (extended ? DEC_RND : 0),
2175 				extended ? ext.base : 0, lim);
2176 			/* Adjust 'size' so that end doesn't move when 'start'
2177 			 * is only changed slightly.
2178 			 */
2179 			if (size > start - old)
2180 				size -= start - old;
2181 			else
2182 				size = 0;
2183 			/* Find end of available space from this start point */
2184 			if (extended) {
2185 				for (p = 0; p < ext.num_ptn; p++) {
2186 					if (p == part)
2187 						continue;
2188 					if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2189 						continue;
2190 					n_s = ext_offset(p);
2191 					if (n_s > start && n_s < lim)
2192 						lim = n_s;
2193 					if (start >= n_s && start < n_s
2194 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2195 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size)) {
2196 						lim = start;
2197 						break;
2198 					}
2199 				}
2200 			} else {
2201 				for (p = 0; p < MBR_PART_COUNT; p++) {
2202 					if (p == part)
2203 						continue;
2204 					if (mboot.mbr_parts[p].mbrp_type == 0)
2205 						continue;
2206 					n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2207 					if (n_s > start && n_s < lim)
2208 						lim = n_s;
2209 					if (start >= n_s && start < n_s
2210 				    + le32toh(mboot.mbr_parts[p].mbrp_size)) {
2211 						lim = start;
2212 						break;
2213 					}
2214 				}
2215 			}
2216 			lim -= start;
2217 			if (lim == 0) {
2218 				printf("Start sector already allocated\n");
2219 				return 0;
2220 			}
2221 			if (size == 0 || size > lim)
2222 				size = lim;
2223 			fl = DEC_SEC;
2224 			if (start % ptn_alignment == ptn_0_offset)
2225 				fl |= DEC_RND_DOWN;
2226 			if (start == 2 * ptn_0_offset)
2227 				fl |= DEC_RND_DOWN | DEC_RND_DOWN_2;
2228 			size = decimal("size", size, fl, 0, lim);
2229 #ifdef BOOTSEL
2230 #ifndef DEFAULT_BOOTEXTCODE
2231 			if (!extended)
2232 #endif
2233 				string("bootmenu", bootmenu_len, tmp_bootmenu);
2234 #endif
2235 		}
2236 	}
2237 
2238 	/*
2239 	 * Before we write these away, we must verify that nothing
2240 	 * untoward has been requested.
2241 	 */
2242 
2243 	if (extended)
2244 		errtext = check_ext_overlap(part, sysid, start, size, 0);
2245 	else
2246 		errtext = check_overlap(part, sysid, start, size, 0);
2247 	if (errtext != NULL && !I_flag) {
2248 		if (f_flag)
2249 			errx(2, "%s\n", errtext);
2250 		printf("%s\n", errtext);
2251 		return 0;
2252 	}
2253 
2254 	/*
2255 	 * Before proceeding, delete any overlapped partitions.
2256 	 * This can only happen if '-f' was supplied on the command line.
2257 	 * Just hope the caller knows what they are doing.
2258 	 * This also fixes the base of each extended partition if the
2259 	 * partition itself has moved.
2260 	 */
2261 	if (!I_flag) {
2262 		if (extended)
2263 			errtext = check_ext_overlap(part, sysid, start, size, 1);
2264 		else
2265 			errtext = check_overlap(part, sysid, start, size, 1);
2266 		if (errtext)
2267 			errx(1, "%s\n", errtext);
2268 	}
2269 
2270 
2271 	if (sysid == 0) {
2272 		/* delete this partition - save info though */
2273 		if (partp == NULL)
2274 			/* must have been trying to create an extended ptn */
2275 			return 0;
2276 		if (start == 0 && size == 0)
2277 			memset(partp, 0, sizeof *partp);
2278 #ifdef BOOTSEL
2279 		if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC)
2280 			memset(boot->mbr_bootsel.mbrbs_nametab[upart], 0,
2281 				sizeof boot->mbr_bootsel.mbrbs_nametab[0]);
2282 #endif
2283 		if (extended)
2284 			delete_ext_ptn(part);
2285 		else
2286 			delete_ptn(part);
2287 		return 1;
2288 	}
2289 
2290 
2291 	if (extended) {
2292 		if (part != -1)
2293 			delete_ext_ptn(part);
2294 		if (start == ext.base + ptn_0_offset)
2295 			/* First one must have been free */
2296 			part = 0;
2297 		else
2298 			part = add_ext_ptn(start, size);
2299 
2300 		/* These must be re-calculated because of the realloc */
2301 		boot = &ext.ptn[part];
2302 		partp = &boot->mbr_parts[0];
2303 		offset = ext_offset(part);
2304 	}
2305 
2306 	partp->mbrp_type = sysid;
2307 	partp->mbrp_start = htole32( start - offset);
2308 	partp->mbrp_size = htole32( size);
2309 	dos(start, &partp->mbrp_scyl, &partp->mbrp_shd, &partp->mbrp_ssect);
2310 	dos(start + size - 1,
2311 		    &partp->mbrp_ecyl, &partp->mbrp_ehd, &partp->mbrp_esect);
2312 #ifdef BOOTSEL
2313 	if (extended) {
2314 		boot->mbr_bootsel_magic = LE_MBR_BS_MAGIC;
2315 		strncpy(boot->mbr_bootsel.mbrbs_nametab[upart], tmp_bootmenu,
2316 			bootmenu_len);
2317 	} else {
2318 		/* We need to bootselect code installed in order to have
2319 		 * somewhere to safely write the menu tag.
2320 		 */
2321 		if (boot->mbr_bootsel_magic != LE_MBR_BS_MAGIC) {
2322 			if (f_flag ||
2323 			    yesno("The bootselect code is not installed, "
2324 				"do you want to install it now?"))
2325 				install_bootsel(MBR_BS_ACTIVE);
2326 		}
2327 		if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
2328 			strncpy(boot->mbr_bootsel.mbrbs_nametab[upart],
2329 				tmp_bootmenu, bootmenu_len);
2330 		}
2331 	}
2332 #endif
2333 
2334 	if (v_flag && !f_flag && yesno("Explicitly specify beg/end address?")) {
2335 		/* this really isn't a good idea.... */
2336 		int tsector, tcylinder, thead;
2337 
2338 		tcylinder = MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect);
2339 		thead = partp->mbrp_shd;
2340 		tsector = MBR_PSECT(partp->mbrp_ssect);
2341 		tcylinder = decimal("beginning cylinder",
2342 				tcylinder, 0, 0, dos_cylinders - 1);
2343 		thead = decimal("beginning head",
2344 				thead, 0, 0, dos_heads - 1);
2345 		tsector = decimal("beginning sector",
2346 				tsector, 0, 1, dos_sectors);
2347 		partp->mbrp_scyl = DOSCYL(tcylinder);
2348 		partp->mbrp_shd = thead;
2349 		partp->mbrp_ssect = DOSSECT(tsector, tcylinder);
2350 
2351 		tcylinder = MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect);
2352 		thead = partp->mbrp_ehd;
2353 		tsector = MBR_PSECT(partp->mbrp_esect);
2354 		tcylinder = decimal("ending cylinder",
2355 				tcylinder, 0, 0, dos_cylinders - 1);
2356 		thead = decimal("ending head",
2357 				thead, 0, 0, dos_heads - 1);
2358 		tsector = decimal("ending sector",
2359 				tsector, 0, 1, dos_sectors);
2360 		partp->mbrp_ecyl = DOSCYL(tcylinder);
2361 		partp->mbrp_ehd = thead;
2362 		partp->mbrp_esect = DOSSECT(tsector, tcylinder);
2363 	}
2364 
2365 	/* If we had to mark an extended partition as deleted because
2366 	 * another request would have overlapped it, now is the time
2367 	 * to do the actual delete.
2368 	 */
2369 	if (extended && f_flag) {
2370 		for (p = ext.num_ptn; --p >= 0;)
2371 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2372 				delete_ext_ptn(p);
2373 	}
2374 	return 1;
2375 }
2376 
2377 static void
2378 print_geometry(void)
2379 {
2380 
2381 	if (sh_flag) {
2382 		printf("DISK=%s\n", disk);
2383 		printf("DLCYL=%d\nDLHEAD=%d\nDLSEC=%d\nDLSIZE=%"PRIdaddr"\n",
2384 			cylinders, heads, sectors, disksectors);
2385 		printf("BCYL=%d\nBHEAD=%d\nBSEC=%d\nBDLSIZE=%"PRIdaddr"\n",
2386 			dos_cylinders, dos_heads, dos_sectors, dos_disksectors);
2387 		printf("NUMEXTPTN=%d\n", ext.num_ptn);
2388 		return;
2389 	}
2390 
2391 	/* Not sh_flag */
2392 	printf("Disk: %s\n", disk);
2393 	printf("NetBSD disklabel disk geometry:\n");
2394 	printf("cylinders: %d, heads: %d, sectors/track: %d "
2395 	    "(%d sectors/cylinder)\ntotal sectors: %"PRIdaddr", "
2396 	    "bytes/sector: %zd\n\n", cylinders, heads, sectors,
2397 	    cylindersectors, disksectors, secsize);
2398 	printf("BIOS disk geometry:\n");
2399 	printf("cylinders: %d, heads: %d, sectors/track: %d "
2400 	    "(%d sectors/cylinder)\ntotal sectors: %"PRIdaddr"\n\n",
2401 	    dos_cylinders, dos_heads, dos_sectors, dos_cylindersectors,
2402 	    dos_disksectors);
2403 	printf("Partitions aligned to %d sector boundaries, offset %d\n\n",
2404 	    ptn_alignment, ptn_0_offset);
2405 }
2406 
2407 /* Find the first active partition, else return MBR_PART_COUNT */
2408 static int
2409 first_active(void)
2410 {
2411 	struct mbr_partition *partp = &mboot.mbr_parts[0];
2412 	int part;
2413 
2414 	for (part = 0; part < MBR_PART_COUNT; part++)
2415 		if (partp[part].mbrp_flag & MBR_PFLAG_ACTIVE)
2416 			return part;
2417 	return MBR_PART_COUNT;
2418 }
2419 
2420 static void
2421 change_active(int which)
2422 {
2423 	struct mbr_partition *partp;
2424 	int part;
2425 	int active = MBR_PART_COUNT;
2426 
2427 	partp = &mboot.mbr_parts[0];
2428 
2429 	if (a_flag && which != -1)
2430 		active = which;
2431 	else
2432 		active = first_active();
2433 	if (!f_flag) {
2434 		if (yesno("Do you want to change the active partition?")) {
2435 			printf ("Choosing %d will make no partition active.\n",
2436 			    MBR_PART_COUNT);
2437 			do {
2438 				active = decimal("active partition",
2439 						active, 0, 0, MBR_PART_COUNT);
2440 			} while (!yesno("Are you happy with this choice?"));
2441 		} else
2442 			return;
2443 	} else
2444 		if (active != MBR_PART_COUNT)
2445 			printf ("Making partition %d active.\n", active);
2446 
2447 	for (part = 0; part < MBR_PART_COUNT; part++)
2448 		partp[part].mbrp_flag &= ~MBR_PFLAG_ACTIVE;
2449 	if (active < MBR_PART_COUNT)
2450 		partp[active].mbrp_flag |= MBR_PFLAG_ACTIVE;
2451 }
2452 
2453 static void
2454 change_bios_geometry(void)
2455 {
2456 	print_geometry();
2457 	if (!yesno("Do you want to change our idea of what BIOS thinks?"))
2458 		return;
2459 
2460 #if defined(USE_DISKLIST)
2461 	if (dl != NULL) {
2462 		struct biosdisk_info *bip;
2463 		int i;
2464 
2465 		for (i = 0; i < dl->dl_nbiosdisks; i++) {
2466 			if (i == 0)
2467 				printf("\nGeometries of known disks:\n");
2468 			bip = &dl->dl_biosdisks[i];
2469 			printf("Disk %d: cylinders %u, heads %u, sectors %u"
2470 				" (%"PRIdaddr" sectors, %dMB)\n",
2471 			    i, bip->bi_cyl, bip->bi_head, bip->bi_sec,
2472 			    bip->bi_lbasecs, SEC_TO_MB(bip->bi_lbasecs));
2473 
2474 		}
2475 		printf("\n");
2476 	}
2477 #endif
2478 	do {
2479 		dos_cylinders = decimal("BIOS's idea of #cylinders",
2480 					dos_cylinders, 0, 0, MAXCYL);
2481 		dos_heads = decimal("BIOS's idea of #heads",
2482 					dos_heads, 0, 0, MAXHEAD);
2483 		dos_sectors = decimal("BIOS's idea of #sectors",
2484 					dos_sectors, 0, 1, MAXSECTOR);
2485 		print_geometry();
2486 	} while (!yesno("Are you happy with this choice?"));
2487 }
2488 
2489 
2490 /***********************************************\
2491 * Change real numbers into strange dos numbers	*
2492 \***********************************************/
2493 static void
2494 dos(int sector, unsigned char *cylinderp, unsigned char *headp,
2495     unsigned char *sectorp)
2496 {
2497 	int cylinder, head;
2498 
2499 	cylinder = sector / dos_cylindersectors;
2500 	sector -= cylinder * dos_cylindersectors;
2501 
2502 	head = sector / dos_sectors;
2503 	sector -= head * dos_sectors;
2504 	if (cylinder > 1023)
2505 		cylinder = 1023;
2506 
2507 	*cylinderp = DOSCYL(cylinder);
2508 	*headp = head;
2509 	*sectorp = DOSSECT(sector + 1, cylinder);
2510 }
2511 
2512 static int
2513 open_disk(int update)
2514 {
2515 	static char namebuf[MAXPATHLEN + 1];
2516 	int flags = update && disk_file == NULL ? O_RDWR : O_RDONLY;
2517 
2518 	if (!F_flag) {
2519 		fd = opendisk(disk, flags, namebuf, sizeof(namebuf), 0);
2520 		if (fd < 0) {
2521 			if (errno == ENODEV)
2522 				warnx("%s is not a character device", namebuf);
2523 			else
2524 				warn("cannot opendisk %s", namebuf);
2525 			return (-1);
2526 		}
2527 		disk = namebuf;
2528 	} else {
2529 		fd = open(disk, flags, 0);
2530 		if (fd == -1) {
2531 			warn("cannot open %s", disk);
2532 			return -1;
2533 		}
2534 	}
2535 
2536 	if (get_params() == -1) {
2537 		close(fd);
2538 		fd = -1;
2539 		return (-1);
2540 	}
2541 	if (disk_file != NULL) {
2542 		/* for testing: read/write data from a disk file */
2543 		wfd = open(disk_file, update ? O_RDWR|O_CREAT : O_RDONLY, 0777);
2544 		if (wfd == -1) {
2545 			warn("%s", disk_file);
2546 			close(fd);
2547 			fd = -1;
2548 			return -1;
2549 		}
2550 	} else
2551 		wfd = fd;
2552 	return (0);
2553 }
2554 
2555 static ssize_t
2556 read_disk(daddr_t sector, void *buf)
2557 {
2558 	ssize_t nr;
2559 
2560 	if (*rfd == -1)
2561 		errx(1, "read_disk(); fd == -1");
2562 
2563 	off_t offs = sector * (off_t)secsize;
2564 	off_t mod = offs & (secsize - 1);
2565 	off_t rnd = offs & ~(secsize - 1);
2566 
2567 	if (lseek(*rfd, rnd, SEEK_SET) == (off_t)-1)
2568 		return -1;
2569 
2570 	if (secsize == 512)
2571 		return read(*rfd, buf, 512);
2572 
2573 	if ((nr = read(*rfd, iobuf, secsize)) != secsize)
2574 		return nr;
2575 
2576 	memcpy(buf, &iobuf[mod], 512);
2577 
2578 	return 512;
2579 }
2580 
2581 static ssize_t
2582 write_disk(daddr_t sector, void *buf)
2583 {
2584 	ssize_t nr;
2585 
2586 	if (wfd == -1)
2587 		errx(1, "write_disk(); wfd == -1");
2588 
2589 	off_t offs = sector * (off_t)secsize;
2590 	off_t mod = offs & (secsize - 1);
2591 	off_t rnd = offs & ~(secsize - 1);
2592 
2593 	if (lseek(wfd, rnd, SEEK_SET) == (off_t)-1)
2594 		return -1;
2595 
2596 	if (secsize == 512)
2597 		return write(wfd, buf, 512);
2598 
2599 	if ((nr = read(wfd, iobuf, secsize)) != secsize)
2600 		return nr;
2601 
2602 	if (lseek(wfd, rnd, SEEK_SET) == (off_t)-1)
2603 		return -1;
2604 
2605 	memcpy(&iobuf[mod], buf, 512);
2606 
2607 	if ((nr = write(wfd, iobuf, secsize)) != secsize)
2608 		return nr;
2609 
2610 	return 512;
2611 }
2612 
2613 static void
2614 guess_geometry(daddr_t _sectors)
2615 {
2616 	dos_sectors = MAXSECTOR;
2617 	dos_heads = MAXHEAD - 1;	/* some BIOS might use 256 */
2618 	dos_cylinders = _sectors / (MAXSECTOR * (MAXHEAD - 1));
2619 	if (dos_cylinders < 1)
2620 		dos_cylinders = 1;
2621 	else if (dos_cylinders > MAXCYL - 1)
2622 		dos_cylinders = MAXCYL - 1;
2623 }
2624 
2625 static int
2626 get_params(void)
2627 {
2628 	if (disk_type != NULL) {
2629 		struct disklabel *tmplabel;
2630 
2631 		if ((tmplabel = getdiskbyname(disk_type)) == NULL) {
2632 			warn("bad disktype");
2633 			return (-1);
2634 		}
2635 		disklabel = *tmplabel;
2636 	} else if (F_flag) {
2637 		struct stat st;
2638 		if (fstat(fd, &st) == -1) {
2639 			warn("fstat");
2640 			return (-1);
2641 		}
2642 		if (st.st_size % 512 != 0) {
2643 			warnx("%s size (%lld) is not divisible "
2644 			    "by sector size (%d)", disk, (long long)st.st_size,
2645 			    512);
2646 		}
2647 		disklabel.d_secperunit = st.st_size / 512;
2648 		guess_geometry(disklabel.d_secperunit);
2649 		disklabel.d_ncylinders = dos_cylinders;
2650 		disklabel.d_ntracks = dos_heads;
2651 		disklabel.d_secsize = 512;
2652 		disklabel.d_nsectors = dos_sectors;
2653 	} else if (ioctl(fd, DIOCGDEFLABEL, &disklabel) == -1) {
2654 		warn("DIOCGDEFLABEL");
2655 		if (ioctl(fd, DIOCGDINFO, &disklabel) == -1) {
2656 			warn("DIOCGDINFO");
2657 			return (-1);
2658 		}
2659 	}
2660 
2661 	disksectors = disklabel.d_secperunit;
2662 	cylinders = disklabel.d_ncylinders;
2663 	heads = disklabel.d_ntracks;
2664 	secsize = disklabel.d_secsize;
2665 	sectors = disklabel.d_nsectors;
2666 
2667 	/* pick up some defaults for the BIOS sizes */
2668 	if (sectors <= MAXSECTOR) {
2669 		dos_cylinders = cylinders;
2670 		dos_heads = heads;
2671 		dos_sectors = sectors;
2672 	} else {
2673 		/* guess - has to better than the above */
2674 		guess_geometry(disksectors);
2675 	}
2676 	dos_disksectors = disksectors;
2677 
2678 	return (0);
2679 }
2680 
2681 #ifdef BOOTSEL
2682 /*
2683  * Rather unfortunately the bootsel 'magic' number is at the end of the
2684  * the structure, and there is no checksum.  So when other operating
2685  * systems install mbr code by only writing the length of their code they
2686  * can overwrite part of the structure but keeping the magic number intact.
2687  * This code attempts to empirically detect this problem.
2688  */
2689 static int
2690 validate_bootsel(struct mbr_bootsel *mbs)
2691 {
2692 	unsigned int key = mbs->mbrbs_defkey;
2693 	unsigned int tmo;
2694 	size_t i;
2695 
2696 	if (v_flag)
2697 		return 0;
2698 
2699 	/*
2700 	 * Check default key is sane
2701 	 * - this is the most likely field to be stuffed
2702 	 * 16 disks and 16 bootable partitions seems enough!
2703 	 * (the keymap decode starts falling apart at that point)
2704 	 */
2705 	if (mbs->mbrbs_flags & MBR_BS_ASCII) {
2706 		if (key != 0 && !(key == '\r'
2707 		    || (key >= '1' && key < '1' + MAX_BIOS_DISKS)
2708 		    || (key >= 'a' && key < 'a' + MAX_BIOS_DISKS)))
2709 			return 1;
2710 	} else {
2711 		if (key != 0 && !(key == SCAN_ENTER
2712 		    || (key >= SCAN_1 && key < SCAN_1 + MAX_BIOS_DISKS)
2713 		    || (key >= SCAN_F1 && key < SCAN_F1 + MAX_BIOS_DISKS)))
2714 			return 1;
2715 	}
2716 
2717 	/* Checking the flags will lead to breakage... */
2718 
2719 	/* Timeout value is expected to be a multiple of a second */
2720 	tmo = htole16(mbs->mbrbs_timeo);
2721 	if (tmo != 0 && tmo != 0xffff && tmo != (10 * tmo + 9) / 182 * 182 / 10)
2722 		return 2;
2723 
2724 	/* Check the menu strings are printable */
2725 	/* Unfortunately they aren't zero filled... */
2726 	for (i = 0; i < sizeof(mbs->mbrbs_nametab); i++) {
2727 		int c = (uint8_t)mbs->mbrbs_nametab[0][i];
2728 		if (c == 0 || isprint(c))
2729 			continue;
2730 		return 3;
2731 	}
2732 
2733 	return 0;
2734 }
2735 #endif
2736 
2737 static int
2738 read_s0(daddr_t offset, struct mbr_sector *boot)
2739 {
2740 	const char *tabletype = offset ? "extended" : "primary";
2741 #ifdef BOOTSEL
2742 	static int reported;
2743 #endif
2744 
2745 	if (read_disk(offset, boot) == -1) {
2746 		warn("Can't read %s partition table", tabletype);
2747 		return -1;
2748 	}
2749 	if (boot->mbr_magic != LE_MBR_MAGIC) {
2750 		if (F_flag && boot->mbr_magic == 0)
2751 			return -1;
2752 		warnx("%s partition table invalid, "
2753 		    "no magic in sector %"PRIdaddr, tabletype, offset);
2754 		return -1;
2755 
2756 	}
2757 #ifdef BOOTSEL
2758 	if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
2759 		/* mbr_bootsel in new location */
2760 		if (validate_bootsel(&boot->mbr_bootsel)) {
2761 			warnx("removing corrupt bootsel information");
2762 			boot->mbr_bootsel_magic = 0;
2763 		}
2764 		return 0;
2765 	}
2766 	if (boot->mbr_bootsel_magic != LE_MBR_MAGIC)
2767 		return 0;
2768 
2769 	/* mbr_bootsel in old location */
2770 	if (!reported)
2771 		warnx("%s partition table: using old-style bootsel information",
2772 		    tabletype);
2773 	reported = 1;
2774 	if (validate_bootsel((void *)((uint8_t *)boot + MBR_BS_OFFSET + 4))) {
2775 		warnx("%s bootsel information corrupt - ignoring", tabletype);
2776 		return 0;
2777 	}
2778 	memmove((uint8_t *)boot + MBR_BS_OFFSET,
2779 		(uint8_t *)boot + MBR_BS_OFFSET + 4,
2780 		sizeof(struct mbr_bootsel));
2781 	if ( ! (boot->mbr_bootsel.mbrbs_flags & MBR_BS_NEWMBR)) {
2782 			/* old style default key */
2783 		int id;
2784 			/* F1..F4 => ptn 0..3, F5+ => disk 0+ */
2785 		id = boot->mbr_bootsel.mbrbs_defkey;
2786 		id -= SCAN_F1;
2787 		if (id >= MBR_PART_COUNT)
2788 			id -= MBR_PART_COUNT; /* Use number of disk */
2789 		else if (mboot.mbr_parts[id].mbrp_type != 0)
2790 			id = le32toh(boot->mbr_parts[id].mbrp_start);
2791 		else
2792 			id = DEFAULT_ACTIVE;
2793 		boot->mbr_bootsel.mbrbs_defkey = id;
2794 	}
2795 	boot->mbr_bootsel_magic = LE_MBR_BS_MAGIC;
2796 		/* highlight that new bootsel code is necessary */
2797 	boot->mbr_bootsel.mbrbs_flags &= ~MBR_BS_NEWMBR;
2798 #endif /* BOOTSEL */
2799 	return 0;
2800 }
2801 
2802 static int
2803 write_mbr(void)
2804 {
2805 	int flag, i;
2806 	daddr_t offset;
2807 	int rval = -1;
2808 
2809 	/*
2810 	 * write enable label sector before write (if necessary),
2811 	 * disable after writing.
2812 	 * needed if the disklabel protected area also protects
2813 	 * sector 0. (e.g. empty disk)
2814 	 */
2815 	flag = 1;
2816 	if (wfd == fd && F_flag == 0 && ioctl(wfd, DIOCWLABEL, &flag) < 0)
2817 		warn("DIOCWLABEL");
2818 	if (write_disk(0, &mboot) == -1) {
2819 		warn("Can't write fdisk partition table");
2820 		goto protect_label;
2821 	}
2822 	if (boot_installed)
2823 		for (i = bootsize; (i -= 0x200) > 0;)
2824 			if (write_disk(i / 0x200, &bootcode[i / 0x200]) == -1) {
2825 				warn("Can't write bootcode");
2826 				goto protect_label;
2827 			}
2828 	for (offset = 0, i = 0; i < ext.num_ptn; i++) {
2829 		if (write_disk(ext.base + offset, ext.ptn + i) == -1) {
2830 			warn("Can't write %dth extended partition", i);
2831 			goto protect_label;
2832 		}
2833 		offset = le32toh(ext.ptn[i].mbr_parts[1].mbrp_start);
2834 	}
2835 	rval = 0;
2836     protect_label:
2837 	flag = 0;
2838 	if (wfd == fd && F_flag == 0 && ioctl(wfd, DIOCWLABEL, &flag) < 0)
2839 		warn("DIOCWLABEL");
2840 	return rval;
2841 }
2842 
2843 static int
2844 yesno(const char *str, ...)
2845 {
2846 	int ch, first;
2847 	va_list ap;
2848 
2849 	va_start(ap, str);
2850 	vprintf(str, ap);
2851 	va_end(ap);
2852 	printf(" [n] ");
2853 
2854 	first = ch = getchar();
2855 	while (ch != '\n' && ch != EOF)
2856 		ch = getchar();
2857 	if (ch == EOF)
2858 		errx(1, "EOF");
2859 	return (first == 'y' || first == 'Y');
2860 }
2861 
2862 static int64_t
2863 decimal(const char *prompt, int64_t dflt, int flags, int64_t minval, int64_t maxval)
2864 {
2865 	int64_t acc = 0;
2866 	int valid;
2867 	int len;
2868 	char *cp;
2869 
2870 	for (;;) {
2871 		if (flags & DEC_SEC) {
2872 			printf("%s: [%" PRId64 "..%" PRId64 "cyl default: %" PRId64 ", %" PRId64 "cyl, %uMB] ",
2873 			    prompt, SEC_TO_CYL(minval), SEC_TO_CYL(maxval),
2874 			    dflt, SEC_TO_CYL(dflt), SEC_TO_MB(dflt));
2875 		} else
2876 			printf("%s: [%" PRId64 "..%" PRId64 " default: %" PRId64 "] ",
2877 			    prompt, minval, maxval, dflt);
2878 
2879 		if (!fgets(lbuf, LBUF, stdin))
2880 			errx(1, "EOF");
2881 		cp = lbuf;
2882 
2883 		cp += strspn(cp, " \t");
2884 		if (*cp == '\n')
2885 			return dflt;
2886 
2887 		if (cp[0] == '$' && cp[1] == '\n')
2888 			return maxval;
2889 
2890 		if (isdigit((unsigned char)*cp) || *cp == '-') {
2891 			acc = strtoll(lbuf, &cp, 10);
2892 			len = strcspn(cp, " \t\n");
2893 			valid = 0;
2894 			if (len != 0 && (flags & DEC_SEC)) {
2895 				if (!strncasecmp(cp, "gb", len)) {
2896 					acc *= 1024;
2897 					valid = 1;
2898 				}
2899 				if (valid || !strncasecmp(cp, "mb", len)) {
2900 					acc *= SEC_IN_1M;
2901 					/* round to whole number of cylinders */
2902 					acc += ptn_alignment / 2;
2903 					acc /= ptn_alignment;
2904 					valid = 1;
2905 				}
2906 				if (valid || !strncasecmp(cp, "cyl", len)) {
2907 					acc *= ptn_alignment;
2908 					/* adjustments for cylinder boundary */
2909 					if (acc == 0 && flags & DEC_RND_0)
2910 						acc += ptn_0_offset;
2911 					if (flags & DEC_RND)
2912 						acc += ptn_0_offset;
2913 					if (flags & DEC_RND_DOWN)
2914 						acc -= ptn_0_offset;
2915 					if (flags & DEC_RND_DOWN_2)
2916 						acc -= ptn_0_offset;
2917 					cp += len;
2918 				}
2919 			}
2920 		}
2921 
2922 		cp += strspn(cp, " \t");
2923 		if (*cp != '\n') {
2924 			lbuf[strlen(lbuf) - 1] = 0;
2925 			printf("%s is not a valid %s number.\n", lbuf,
2926 			    flags & DEC_SEC ? "sector" : "decimal");
2927 			continue;
2928 		}
2929 
2930 		if (acc >= minval && acc <= maxval)
2931 			return acc;
2932 		printf("%" PRId64 " is not between %" PRId64 " and %" PRId64 ".\n", acc, minval, maxval);
2933 	}
2934 }
2935 
2936 static int
2937 ptn_id(const char *prompt, int *extended)
2938 {
2939 	unsigned int acc = 0;
2940 	char *cp;
2941 
2942 	for (;; printf("%s is not a valid partition number.\n", lbuf)) {
2943 		printf("%s: [none] ", prompt);
2944 
2945 		if (!fgets(lbuf, LBUF, stdin))
2946 			errx(1, "EOF");
2947 		lbuf[strlen(lbuf)-1] = '\0';
2948 		cp = lbuf;
2949 
2950 		cp += strspn(cp, " \t");
2951 		*extended = 0;
2952 		if (*cp == 0)
2953 			return -1;
2954 
2955 		if (*cp == 'E' || *cp == 'e') {
2956 			cp++;
2957 			*extended = 1;
2958 		}
2959 
2960 		acc = strtoul(cp, &cp, 10);
2961 
2962 		cp += strspn(cp, " \t");
2963 		if (*cp != '\0')
2964 			continue;
2965 
2966 		if (*extended || acc < MBR_PART_COUNT)
2967 			return acc;
2968 	}
2969 }
2970 
2971 #ifdef BOOTSEL
2972 static void
2973 string(const char *prompt, int length, char *buf)
2974 {
2975 	int len;
2976 
2977 	for (;;) {
2978 		printf("%s: [%.*s] ", prompt, length, buf);
2979 
2980 		if (!fgets(lbuf, LBUF, stdin))
2981 			errx(1, "EOF");
2982 		len = strlen(lbuf);
2983 		if (len <= 1)
2984 			/* unchanged if just <enter> */
2985 			return;
2986 		/* now strip trailing spaces, <space><enter> deletes string */
2987 		do
2988 			lbuf[--len] = 0;
2989 		while (len != 0 && lbuf[len - 1] == ' ');
2990 		if (len < length)
2991 			break;
2992 		printf("'%s' is longer than %d characters.\n",
2993 		    lbuf, length - 1);
2994 	}
2995 	strncpy(buf, lbuf, length);
2996 }
2997 #endif
2998 
2999 static int
3000 type_match(const void *key, const void *item)
3001 {
3002 	const int *idp = key;
3003 	const struct mbr_ptype *ptr = item;
3004 
3005 	if (*idp < ptr->id)
3006 		return (-1);
3007 	if (*idp > ptr->id)
3008 		return (1);
3009 	return (0);
3010 }
3011 
3012 static const char *
3013 get_type(int type)
3014 {
3015 	struct mbr_ptype *ptr;
3016 
3017 	ptr = bsearch(&type, mbr_ptypes, KNOWN_SYSIDS,
3018 	    sizeof(mbr_ptypes[0]), type_match);
3019 	if (ptr == 0)
3020 		return ("unknown");
3021 	return (ptr->name);
3022 }
3023 
3024 static int
3025 read_gpt(daddr_t offset, struct gpt_hdr *gptp)
3026 {
3027 	char buf[512];
3028 	struct gpt_hdr *hdr = (void *)buf;
3029 	const char *tabletype = GPT_TYPE(offset);
3030 
3031 	if (read_disk(offset, buf) == -1) {
3032 		warn("Can't read %s GPT header", tabletype);
3033 		return -1;
3034 	}
3035 	(void)memcpy(gptp, buf, GPT_HDR_SIZE);
3036 
3037 	/* GPT CRC should be calculated with CRC field preset to zero */
3038 	hdr->hdr_crc_self = 0;
3039 
3040 	if (memcmp(gptp->hdr_sig, GPT_HDR_SIG, sizeof(gptp->hdr_sig))
3041 	    || gptp->hdr_lba_self != (uint64_t)offset
3042 	    || crc32(0, (void *)hdr, gptp->hdr_size) != gptp->hdr_crc_self) {
3043 		/* not a GPT */
3044 		(void)memset(gptp, 0, GPT_HDR_SIZE);
3045 	}
3046 
3047 	if (v_flag && gptp->hdr_size != 0) {
3048 		printf("Found %s GPT header CRC %"PRIu32" "
3049 		    "at sector %"PRIdaddr", backup at %"PRIdaddr"\n",
3050 		    tabletype, gptp->hdr_crc_self, offset, gptp->hdr_lba_alt);
3051 	}
3052 	return gptp->hdr_size;
3053 
3054 }
3055 
3056 static int
3057 delete_gpt(struct gpt_hdr *gptp)
3058 {
3059 	char buf[512];
3060 	struct gpt_hdr *hdr = (void *)buf;
3061 
3062 	if (gptp->hdr_size == 0)
3063 		return 0;
3064 
3065 	/* don't accidently overwrite something important */
3066 	if (gptp->hdr_lba_self != GPT_HDR_BLKNO &&
3067 	    gptp->hdr_lba_self != (uint64_t)disksectors - 1) {
3068 		warnx("given GPT header location doesn't seem correct");
3069 		return -1;
3070 	}
3071 
3072 	(void)memcpy(buf, gptp, GPT_HDR_SIZE);
3073 	/*
3074 	 * Don't really delete GPT, just "disable" it, so it can
3075 	 * be recovered later in case of mistake or something
3076 	 */
3077 	(void)memset(hdr->hdr_sig, 0, sizeof(gptp->hdr_sig));
3078 	if (write_disk(gptp->hdr_lba_self, hdr) == -1) {
3079 		warn("can't delete %s GPT header",
3080 		    GPT_TYPE(gptp->hdr_lba_self));
3081 		return -1;
3082 	}
3083 	(void)memset(gptp, 0, GPT_HDR_SIZE);
3084 	return 1;
3085 }
3086