xref: /netbsd-src/sbin/fdisk/fdisk.c (revision 53d1339bf7f9c7367b35a9e1ebe693f9b047a47b)
1 /*	$NetBSD: fdisk.c,v 1.159 2020/05/24 21:02:12 wiz 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 1.159 2020/05/24 21:02:12 wiz 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 #include <zlib.h>
62 
63 #if !HAVE_NBTOOL_CONFIG_H
64 #include <sys/disklabel.h>
65 #include <sys/disklabel_gpt.h>
66 #include <sys/bootblock.h>
67 #include <sys/ioctl.h>
68 #include <sys/sysctl.h>
69 #include <disktab.h>
70 #include <util.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 #endif /* HAVE_NBTOOL_CONFIG_H */
79 
80 #ifndef	DEFAULT_BOOTDIR
81 #define	DEFAULT_BOOTDIR		"/usr/mdec"
82 #endif
83 
84 #define	LE_MBR_MAGIC		htole16(MBR_MAGIC)
85 #define	LE_MBR_BS_MAGIC		htole16(MBR_BS_MAGIC)
86 
87 #ifdef BOOTSEL
88 
89 #define	DEFAULT_BOOTCODE	"mbr"
90 #define	DEFAULT_BOOTSELCODE	"mbr_bootsel"
91 #define	DEFAULT_BOOTEXTCODE	"mbr_ext"
92 
93 /* Scan values for the various keys we use, as returned by the BIOS */
94 #define	SCAN_ENTER	0x1c
95 #define	SCAN_F1		0x3b
96 #define	SCAN_1		0x2
97 
98 
99 #define	MAX_BIOS_DISKS	16	/* Going beyond F12 is hard though! */
100 
101 /* We same the dflt 'boot partition' as a disk block, with some magic values. */
102 #define DEFAULT_ACTIVE	(~(daddr_t)0)
103 #define	DEFAULT_DISK(n)	(DEFAULT_ACTIVE - MAX_BIOS_DISKS + (n))
104 
105 #endif
106 
107 #define GPT_TYPE(offs) ((offs) == GPT_HDR_BLKNO ?  "primary" : "secondary")
108 
109 #ifndef PRIdaddr
110 #define PRIdaddr PRId64
111 #endif
112 
113 #ifndef _PATH_DEFDISK
114 #define _PATH_DEFDISK	"/dev/rwd0d"
115 #endif
116 
117 struct {
118 	struct mbr_sector *ptn;		/* array of pbrs */
119 	daddr_t		base;		/* first sector of ext. ptn */
120 	daddr_t		limit;		/* last sector of ext. ptn */
121 	int		num_ptn;	/* number of contained partitions */
122 	int		ptn_id;		/* entry in mbr */
123 	int		is_corrupt;	/* 1 if extended chain illegal */
124 } ext;
125 
126 #define LBUF 100
127 static char lbuf[LBUF];
128 
129 static const char *disk = _PATH_DEFDISK;
130 
131 static struct disklabel disklabel;		/* disk parameters */
132 
133 static struct mbr_sector mboot;
134 
135 static const char *boot_dir = DEFAULT_BOOTDIR;
136 static char *boot_path = NULL;			/* name of file we actually opened */
137 
138 #ifdef BOOTSEL
139 #define BOOTSEL_OPTIONS	"B"
140 #else
141 #define BOOTSEL_OPTIONS
142 #define change_part(e, p, id, st, sz, bm) change__part(e, p, id, st, sz)
143 #endif
144 #define OPTIONS	BOOTSEL_OPTIONS "0123FSafgiIluvA:b:c:E:r:s:w:z:"
145 
146 /*
147  * Disk geometry and partition alignment.
148  *
149  * Modern disks do not have a fixed geomery and will always give a 'faked'
150  * geometry that matches the ATA standard - max 16 heads and 256 sec/track.
151  * The ATA geometry allows access to 2^28 sectors (as does LBA mode).
152  *
153  * The BIOS calls originally used an 8bit register for cylinder, head and
154  * sector. Later 2 bits were stolen from the sector number and added to
155  * cylinder number. The BIOS will translate this faked geometry either to
156  * the geometry reported by the disk, or do LBA reads (possibly LBA48).
157  * BIOS CHS reads have all sorts of limits, but 2^24 is absolute.
158  * For historic reasons the BIOS geometry is the called the dos geometry!
159  *
160  * If you know the disks real geometry it is usually worth aligning
161  * disk partitions to cylinder boundaries (certainly traditional!).
162  * For 'mbr' disks this has always been done with the BIOS geometry.
163  * The first track (typically 63 sectors) is reserved because the first
164  * sector is used for boot code. Similarly the data partition in an
165  * extended partition will start one track in. If an extended partition
166  * starts at the beginning of the disk you lose 2 tracks.
167  *
168  * However non-magnetic media in particular has physical sectors that are
169  * not the same size as those reported, so has to do read modify write
170  * sequences for misaligned transfers. The alignment of partitions to
171  * cylinder boundaries makes this happen all the time.
172  *
173  * It is thus sensible to align partitions on a sensible sector boundary.
174  * For instance 1MB (2048 sectors).
175  * Common code can do this by using a geometry with 1 head and 2048
176  * sectors per track.
177  */
178 
179 /* Disks reported geometry and overall size from device driver */
180 static unsigned int cylinders, sectors, heads;
181 static daddr_t disksectors;
182 #define cylindersectors (heads * sectors)
183 
184 /* Geometry from the BIOS */
185 static unsigned int dos_cylinders;
186 static unsigned int dos_heads;
187 static unsigned int dos_sectors;
188 static daddr_t dos_disksectors;
189 #define dos_cylindersectors (dos_heads * dos_sectors)
190 #define dos_totalsectors (dos_heads * dos_sectors * dos_cylinders)
191 
192 #define DOSSECT(s,c)	(((s) & 0x3f) | (((c) >> 2) & 0xc0))
193 #define DOSCYL(c)	((c) & 0xff)
194 #define SEC_IN_1M (1024 * 1024 / secsize)
195 #define SEC_TO_MB(sec) ((unsigned int)(((sec) + SEC_IN_1M / 2) / SEC_IN_1M))
196 #define SEC_TO_CYL(sec) (((sec) + dos_cylindersectors/2) / dos_cylindersectors)
197 
198 #define MAXCYL		1024	/* Usual limit is 1023 */
199 #define	MAXHEAD		256	/* Usual limit is 255 */
200 #define	MAXSECTOR	63
201 static int partition = -1;
202 
203 /* Alignment of partition, and offset if first sector unusable */
204 static unsigned int ptn_alignment;	/* default dos_cylindersectors */
205 static unsigned int ptn_0_offset;	/* default dos_sectors */
206 
207 static int fd = -1, wfd = -1, *rfd = &fd;
208 static char *disk_file = NULL;
209 static char *disk_type = NULL;
210 
211 static int a_flag;		/* set active partition */
212 static int i_flag;		/* init bootcode */
213 static int I_flag;		/* ignore errors */
214 static int u_flag;		/* update partition data */
215 static int v_flag;		/* more verbose */
216 static int sh_flag;		/* Output data as shell defines */
217 static int f_flag;		/* force --not interactive */
218 static int g_flag;		/* preserve GPT headers */
219 static int s_flag;		/* set id,offset,size */
220 static int b_flag;		/* Set cyl, heads, secs (as c/h/s) */
221 static int B_flag;		/* Edit/install bootselect code */
222 static int E_flag;		/* extended partition number */
223 static int b_cyl, b_head, b_sec;  /* b_flag values. */
224 
225 #if !HAVE_NBTOOL_CONFIG_H
226 static int F_flag = 0;
227 #else
228 /* Tool - force 'file' mode to avoid unsupported functions and ioctls */
229 static int F_flag = 1;
230 #endif
231 
232 static struct gpt_hdr gpt1, gpt2;	/* GUID partition tables */
233 
234 static struct mbr_sector bootcode[8192 / sizeof (struct mbr_sector)];
235 static ssize_t secsize = 512;	/* sector size */
236 static char *iobuf;		/* buffer for non 512 sector I/O */
237 static int bootsize;		/* actual size of bootcode */
238 static int boot_installed;	/* 1 if we've copied code into the mbr */
239 
240 #if defined(USE_DISKLIST)
241 #include <machine/cpu.h>
242 static struct disklist *dl;
243 #endif
244 
245 
246 #define KNOWN_SYSIDS	(sizeof(mbr_ptypes)/sizeof(mbr_ptypes[0]))
247 
248 __dead static void	usage(void);
249 static void	print_s0(int);
250 static void	print_part(struct mbr_sector *, int, daddr_t);
251 static void	print_mbr_partition(struct mbr_sector *, int, daddr_t, daddr_t, int);
252 static void	print_pbr(daddr_t, int, uint8_t);
253 static int	is_all_zero(const unsigned char *, size_t);
254 static void	printvis(int, const char *, const char *, size_t);
255 static int	read_boot(const char *, void *, size_t, int);
256 static void	init_sector0(int);
257 static void	intuit_translated_geometry(void);
258 static void	get_bios_geometry(void);
259 static void	get_extended_ptn(void);
260 static void	get_ptn_alignmemt(void);
261 #if defined(USE_DISKLIST)
262 static void	get_diskname(const char *, char *, size_t);
263 #endif
264 static int	change_part(int, int, int, daddr_t, daddr_t, char *);
265 static void	print_geometry(void);
266 static int	first_active(void);
267 static void	change_active(int);
268 static void	change_bios_geometry(void);
269 static void	dos(int, unsigned char *, unsigned char *, unsigned char *);
270 static int	open_disk(int);
271 static ssize_t	read_disk(daddr_t, void *);
272 static ssize_t	write_disk(daddr_t, void *);
273 static int	get_params(void);
274 static int	read_s0(daddr_t, struct mbr_sector *);
275 static int	write_mbr(void);
276 static int	read_gpt(daddr_t, struct gpt_hdr *);
277 static int	delete_gpt(struct gpt_hdr *);
278 static int	yesno(const char *, ...) __printflike(1, 2);
279 static int64_t	decimal(const char *, int64_t, int, int64_t, int64_t);
280 #define DEC_SEC		1		/* asking for a sector number */
281 #define	DEC_RND		2		/* round to end of first track */
282 #define	DEC_RND_0	4		/* convert 0 to size of a track */
283 #define DEC_RND_DOWN	8		/* subtract 1 track */
284 #define DEC_RND_DOWN_2	16		/* subtract 2 tracks */
285 static int	ptn_id(const char *, int *);
286 static int	type_match(const void *, const void *);
287 static const char *get_type(int);
288 static int	get_mapping(int, unsigned int *, unsigned int *, unsigned int *, unsigned long *);
289 #ifdef BOOTSEL
290 static daddr_t	configure_bootsel(daddr_t);
291 static void	install_bootsel(int);
292 static daddr_t	get_default_boot(void);
293 static void	set_default_boot(daddr_t);
294 static void	string(const char *, int, char *);
295 #endif
296 
297 static void
298 initvar_disk(const char **diskp)
299 {
300 #if !HAVE_NBTOOL_CONFIG_H
301 	int mib[2];
302 	size_t len;
303 	char *root_device;
304 
305 	mib[0] = CTL_KERN;
306 	mib[1] = KERN_ROOT_DEVICE;
307 	if (sysctl(mib, 2, NULL, &len, NULL, 0) == -1 ||
308 	    (root_device = malloc(len)) == NULL ||
309 	    sysctl(mib, 2, root_device, &len, NULL, 0) == -1)
310 		return;
311 
312 	*diskp = root_device;
313 #endif /* HAVE_NBTOOL_CONFIG_H */
314 }
315 
316 static int
317 getnum(const char *str, int *num)
318 {
319 	char *e;
320 	long l;
321 
322 	errno = 0;
323 	l = strtol(str, &e, 0);
324 	if (str[0] == '\0' || *e != '\0')
325 		return -1;
326 	if (errno == ERANGE && (l == LONG_MAX || l == LONG_MIN))
327 		return -1;
328 	/* XXX: truncation */
329 	*num = (int)l;
330 	return 0;
331 }
332 
333 /* [<sysid>][/[<start>][/[<size>][/[<bootmenu>]]]] */
334 static int
335 parse_s(char *arg, int *csysid, unsigned *cstart, unsigned *csize,
336     char **cbootmenu)
337 {
338 	char *ptr;
339 	int num;
340 
341 	if ((ptr = strchr(arg, '/')) != NULL)
342 		*ptr++ = '\0';
343 
344 	if (*arg) {
345 		if (getnum(arg, &num) == -1)
346 			return -1;
347 		*csysid = num;
348 	}
349 	if (ptr == NULL)
350 		return 0;
351 
352 	arg = ptr;
353 	if ((ptr = strchr(arg, '/')) != NULL)
354 		*ptr++ = '\0';
355 	if (*arg) {
356 		if (getnum(arg, &num) == -1)
357 			return -1;
358 		*cstart = num;
359 	}
360 	if (ptr == NULL)
361 		return 0;
362 
363 	arg = ptr;
364 	if ((ptr = strchr(arg, '/')) != NULL)
365 		*ptr++ = '\0';
366 	if (*arg) {
367 		if (getnum(arg, &num) == -1)
368 			return -1;
369 		*csize = num;
370 	}
371 	if (ptr != NULL && *ptr)
372 		*cbootmenu = ptr;
373 	return 0;
374 }
375 
376 int
377 main(int argc, char *argv[])
378 {
379 	struct stat sb;
380 	int ch;
381 	size_t len;
382 	char *cp;
383 	int n;
384 #ifdef BOOTSEL
385 	daddr_t default_ptn;		/* start sector of default ptn */
386 #endif
387 	char *cbootmenu = 0;
388 
389 	int csysid;	/* For the s_flag. */
390 	unsigned int cstart, csize;
391 	a_flag = u_flag = sh_flag = f_flag = s_flag = b_flag = 0;
392 	i_flag = B_flag = 0;
393 	v_flag = 0;
394 	E_flag = 0;
395 	csysid = -1;
396 	cstart = csize = ~0;
397 	while ((ch = getopt(argc, argv, OPTIONS)) != -1) {
398 		switch (ch) {
399 		case '0':
400 			partition = 0;
401 			break;
402 		case '1':
403 			partition = 1;
404 			break;
405 		case '2':
406 			partition = 2;
407 			break;
408 		case '3':
409 			partition = 3;
410 			break;
411 		case 'E':	/* Extended partition number */
412 			E_flag = 1;
413 			partition = strtoul(optarg, &cp, 0);
414 			if (*cp || partition < 0)
415 				errx(1, "Bad partition number -E %s.", optarg);
416 			break;
417 #ifdef BOOTSEL
418 		case 'B':	/* Bootselect parameters */
419 			B_flag = 1;
420 			break;
421 #endif
422 		case 'F':	/* device argument is really a file */
423 			F_flag = 1;
424 			break;
425 		case 'S':	/* Output as shell variables */
426 			sh_flag = 1;
427 			break;
428 		case 'a':	/* Set active partition */
429 			a_flag = 1;
430 			break;
431 		case 'f':	/* Non interactive */
432 			f_flag = 1;
433 			break;
434 		case 'g':	/* Preserve GPT headers */
435 			g_flag = 1;
436 			break;
437 		case 'i':	/* Always update bootcode */
438 			i_flag = 1;
439 			break;
440 		case 'I':	/* Ignore errors */
441 			I_flag = 1;
442 			break;
443 		case 'l':	/* List known partition types */
444 			for (len = 0; len < KNOWN_SYSIDS; len++)
445 				printf("%03d %s\n", mbr_ptypes[len].id,
446 				    mbr_ptypes[len].name);
447 			return 0;
448 		case 'u':	/* Update partition details */
449 			u_flag = 1;
450 			break;
451 		case 'v':	/* Be verbose */
452 			v_flag++;
453 			break;
454 		case 's':	/* Partition details */
455 			s_flag = 1;
456 
457 			if (parse_s(optarg, &csysid, &cstart, &csize,
458 			    &cbootmenu) == -1)
459 				errx(1, "Bad argument to the -s flag.");
460 			break;
461 		case 'b':	/* BIOS geometry */
462 			b_flag = 1;
463 			if (sscanf(optarg, "%d/%d/%d%n", &b_cyl, &b_head,
464 			    &b_sec, &n) != 3 || optarg[n] != 0)
465 				errx(1, "Bad argument to the -b flag.");
466 			if (b_cyl > MAXCYL)
467 				b_cyl = MAXCYL;
468 			break;
469 		case 'A':	/* Partition alignment[/offset] */
470 			if (sscanf(optarg, "%u%n/%u%n", &ptn_alignment,
471 				    &n, &ptn_0_offset, &n) < 1
472 			    || optarg[n] != 0
473 			    || ptn_0_offset > ptn_alignment)
474 				errx(1, "Bad argument to the -A flag.");
475 			if (ptn_0_offset == 0)
476 				ptn_0_offset = ptn_alignment;
477 			break;
478 		case 'c':	/* file/directory containing boot code */
479 			if (strchr(optarg, '/') != NULL &&
480 			    stat(optarg, &sb) == 0 &&
481 			    (sb.st_mode & S_IFMT) == S_IFDIR) {
482 				boot_dir = optarg;
483 				break;
484 			}
485 			bootsize = read_boot(optarg, bootcode,
486 						sizeof bootcode, 1);
487 			i_flag = 1;
488 			break;
489 		case 'r':	/* read data from disk_file (not raw disk) */
490 			rfd = &wfd;
491 			/* FALLTHROUGH */
492 		case 'w':	/* write data to disk_file */
493 			disk_file = optarg;
494 			break;
495 		case 't':
496 			if (setdisktab(optarg) == -1)
497 				errx(EXIT_FAILURE, "bad disktab");
498 			break;
499 		case 'T':
500 			disk_type = optarg;
501 			break;
502 		case 'z':
503 			secsize = atoi(optarg);
504 			if (secsize <= 512)
505 out:				 errx(EXIT_FAILURE, "Invalid sector size %zd",
506 				    secsize);
507 			for (ch = secsize; (ch & 1) == 0; ch >>= 1)
508 				continue;
509 			if (ch != 1)
510 				goto out;
511 			break;
512 		default:
513 			usage();
514 		}
515 	}
516 	argc -= optind;
517 	argv += optind;
518 
519 	if (disk_type != NULL && getdiskbyname(disk_type) == NULL)
520 		errx(EXIT_FAILURE, "bad disktype");
521 
522 	if (sh_flag && (a_flag || i_flag || u_flag || f_flag || s_flag))
523 		usage();
524 
525 	if (B_flag && f_flag) {
526 		warnx("Bootselector may only be configured interactively");
527 		usage();
528 	}
529 
530 	if (f_flag && u_flag && !s_flag) {
531 		warnx("Partition data not specified");
532 		usage();
533 	}
534 
535 	if (s_flag && partition == -1) {
536 		warnx("-s flag requires a partition selected.");
537 		usage();
538 	}
539 
540 	if (argc > 1)
541 		usage();
542 
543 	if (argc > 0)
544 		disk = argv[0];
545 	else if (!F_flag) {
546 		/* Default to boot device */
547 		initvar_disk(&disk);
548 	}
549 
550 	if (!F_flag && stat(disk, &sb) == 0 && S_ISREG(sb.st_mode))
551 		F_flag = 1;
552 
553 	if (open_disk(B_flag || a_flag || i_flag || u_flag) < 0)
554 		exit(1);
555 
556 	if (secsize > 512) {
557 		if ((iobuf = malloc(secsize)) == NULL)
558 			err(EXIT_FAILURE, "Cannot allocate %zd buffer",
559 			    secsize);
560 	}
561 
562 	if (read_s0(0, &mboot))
563 		/* must have been a blank disk */
564 		init_sector0(1);
565 
566 	read_gpt(GPT_HDR_BLKNO, &gpt1);
567 	read_gpt(disksectors - 1, &gpt2);
568 
569 	if (b_flag) {
570 		dos_cylinders = b_cyl;
571 		dos_heads = b_head;
572 		dos_sectors = b_sec;
573 	} else {
574 		get_bios_geometry();
575 	}
576 
577 	if (ptn_alignment == 0)
578 		get_ptn_alignmemt();
579 
580 	get_extended_ptn();
581 
582 #ifdef BOOTSEL
583 	default_ptn = get_default_boot();
584 #endif
585 
586 	if (E_flag && !u_flag && partition >= ext.num_ptn)
587 		errx(1, "Extended partition %d is not defined.", partition);
588 
589 	/* Do the update stuff! */
590 	if (u_flag) {
591 		if (!f_flag && !b_flag)
592 			change_bios_geometry();
593 
594 		if (s_flag)
595 			change_part(E_flag, partition, csysid, cstart, csize,
596 				cbootmenu);
597 		else {
598 			int part = partition, chg_ext = E_flag, prompt = 1;
599 			do {
600 				if (prompt) {
601 					printf("\n");
602 					print_s0(partition);
603 				}
604 				if (partition == -1)
605 					part = ptn_id(
606 				    "Which partition do you want to change?",
607 							&chg_ext);
608 				if (part < 0)
609 					break;
610 				prompt = change_part(chg_ext, part, 0, 0, 0, 0);
611 			} while (partition == -1);
612 		}
613 	} else {
614 		if (!i_flag && !B_flag) {
615 			print_geometry();
616 			print_s0(partition);
617 		}
618 	}
619 
620 	if (a_flag && !E_flag)
621 		change_active(partition);
622 
623 #ifdef BOOTSEL
624 	if (B_flag || u_flag || i_flag)
625 		/* Ensure the mbr code supports this configuration */
626 		install_bootsel(0);
627 	if (B_flag)
628 		default_ptn = configure_bootsel(default_ptn);
629 	set_default_boot(default_ptn);
630 #else
631 	if (i_flag)
632 		init_sector0(0);
633 #endif
634 
635 	if (u_flag || a_flag || i_flag || B_flag) {
636 		if (!f_flag) {
637 			printf("\nWe haven't written the MBR back to disk "
638 			       "yet.  This is your last chance.\n");
639 			if (u_flag)
640 				print_s0(-1);
641 			if (gpt1.hdr_size != 0 || gpt2.hdr_size != 0)
642 				printf("\nWARNING: The disk is carrying "
643 				       "GUID Partition Tables.\n"
644 				       "         If you continue, "
645 				       "GPT headers will be deleted.\n\n");
646 			if (yesno("Should we write new partition table?")) {
647 				delete_gpt(&gpt1);
648 				delete_gpt(&gpt2);
649 				write_mbr();
650 			}
651 		} else {
652 			if (delete_gpt(&gpt1) > 0)
653 				warnx("Primary GPT header was deleted");
654 			if (delete_gpt(&gpt2) > 0)
655 				warnx("Secondary GPT header was deleted");
656 			write_mbr();
657 		}
658 	}
659 
660 	exit(0);
661 }
662 
663 static void
664 usage(void)
665 {
666 	int indent = 7 + (int)strlen(getprogname()) + 1;
667 
668 	(void)fprintf(stderr, "usage: %s [-aBFfgIilSuv] "
669 		"[-A ptn_alignment[/ptn_0_offset]] \\\n"
670 		"%*s[-b cylinders/heads/sectors] \\\n"
671 		"%*s[-0123 | -E num "
672 		"[-s [id][/[start][/[size][/bootmenu]]]] \\\n"
673 		"%*s[-t disktab] [-T disktype] \\\n"
674 		"%*s[-c bootcode] "
675 		"[-r|-w file] [-z sectorsize] [device]\n"
676 		"\t-a change active partition\n"
677 		"\t-f force - not interactive\n"
678 		"\t-g preserve existing GPT headers\n"
679 		"\t-i initialise MBR code\n"
680 		"\t-I ignore errors about no space or overlapping partitions\n"
681 		"\t-l list partition types\n"
682 		"\t-u update partition data\n"
683 		"\t-v verbose output, -v -v more verbose still\n"
684 		"\t-B update bootselect options\n"
685 		"\t-F treat device as a regular file\n"
686 		"\t-S output as shell defines\n"
687 		"\t-r and -w access 'file' for non-destructive testing\n",
688 		getprogname(), indent, "", indent, "", indent, "", indent, "");
689 	exit(1);
690 }
691 
692 static daddr_t
693 ext_offset(int part)
694 {
695 	daddr_t offset = ext.base;
696 
697 	if (part != 0)
698 		offset += le32toh(ext.ptn[part - 1].mbr_parts[1].mbrp_start);
699 	return offset;
700 }
701 
702 static void
703 print_s0(int which)
704 {
705 	int part;
706 
707 	if (which == -1) {
708 		if (!sh_flag)
709 			printf("Partition table:\n");
710 		for (part = 0; part < MBR_PART_COUNT; part++) {
711 			if (!sh_flag)
712 				printf("%d: ", part);
713 			print_part(&mboot, part, 0);
714 		}
715 		if (!sh_flag) {
716 			if (ext.is_corrupt)
717 				printf("Extended partition table is corrupt\n");
718 			else
719 				if (ext.num_ptn != 0)
720 					printf("Extended partition table:\n");
721 		}
722 		for (part = 0; part < ext.num_ptn; part++) {
723 			if (!sh_flag)
724 				printf("E%d: ", part);
725 			print_part(&ext.ptn[part], 0, ext_offset(part));
726 			if (!sh_flag && v_flag >= 2) {
727 				printf("link: ");
728 				print_mbr_partition(&ext.ptn[part], 1,
729 						ext_offset(part), ext.base, 0);
730 			}
731 		}
732 #ifdef BOOTSEL
733 		if (!sh_flag && mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
734 			int tmo;
735 
736 			printf("Bootselector ");
737 			if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ACTIVE) {
738 				printf("enabled");
739 				tmo = le16toh(mboot.mbr_bootsel.mbrbs_timeo);
740 				if (tmo == 0xffff)
741 					printf(", infinite timeout");
742 				else
743 					printf(", timeout %d seconds",
744 						    (10 * tmo + 9) / 182);
745 			} else
746 				printf("disabled");
747 			printf(".\n");
748 		}
749 #endif
750 		if (!sh_flag) {
751 			int active = first_active();
752 			if (active == MBR_PART_COUNT)
753 				printf("No active partition.\n");
754 			else
755 				printf("First active partition: %d\n", active);
756 		}
757 		if (!sh_flag)
758 			printf("Drive serial number: %"PRIu32" (0x%08x)\n",
759 			    le32toh(mboot.mbr_dsn),
760 			    le32toh(mboot.mbr_dsn));
761 		return;
762 	}
763 
764 	if (E_flag) {
765 		if (!sh_flag)
766 			printf("Extended partition E%d:\n", which);
767 		if (which > ext.num_ptn)
768 			printf("Undefined\n");
769 		else
770 			print_part(&ext.ptn[which], 0, ext_offset(which));
771 	} else {
772 		if (!sh_flag)
773 			printf("Partition %d:\n", which);
774 		print_part(&mboot, which, 0);
775 	}
776 }
777 
778 static void
779 print_part(struct mbr_sector *boot, int part, daddr_t offset)
780 {
781 	struct mbr_partition *partp;
782 	const char *e;
783 
784 	if (!sh_flag) {
785 		print_mbr_partition(boot, part, offset, 0, 0);
786 		return;
787 	}
788 
789 	partp = &boot->mbr_parts[part];
790 	if (boot != &mboot) {
791 		part = boot - ext.ptn;
792 		e = "E";
793 	} else
794 		e = "";
795 
796 	if (partp->mbrp_type == 0) {
797 		printf("PART%s%dSIZE=0\n", e, part);
798 		return;
799 	}
800 
801 	printf("PART%s%dID=%d\n", e, part, partp->mbrp_type);
802 	printf("PART%s%dSIZE=%u\n", e, part, le32toh(partp->mbrp_size));
803 	printf("PART%s%dSTART=%"PRIdaddr"\n", e, part,
804 	    offset + le32toh(partp->mbrp_start));
805 	printf("PART%s%dFLAG=0x%x\n", e, part, partp->mbrp_flag);
806 	printf("PART%s%dBCYL=%d\n", e, part,
807 	    MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect));
808 	printf("PART%s%dBHEAD=%d\n", e, part, partp->mbrp_shd);
809 	printf("PART%s%dBSEC=%d\n", e, part, MBR_PSECT(partp->mbrp_ssect));
810 	printf("PART%s%dECYL=%d\n", e, part,
811 	    MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect));
812 	printf("PART%s%dEHEAD=%d\n", e, part, partp->mbrp_ehd);
813 	printf("PART%s%dESEC=%d\n", e, part, MBR_PSECT(partp->mbrp_esect));
814 }
815 
816 static void
817 pr_cyls(daddr_t sector, int is_end)
818 {
819 	unsigned long cyl, head, sect;
820 	cyl = sector / dos_cylindersectors;
821 	sect = sector - cyl * dos_cylindersectors;
822 	head = sect / dos_sectors;
823 	sect -= head * dos_sectors;
824 
825 	printf("%lu", cyl);
826 
827 	if (is_end) {
828 		if (head == dos_heads - 1 && sect == dos_sectors - 1)
829 			return;
830 	} else {
831 		if (head == 0 && sect == 0)
832 			return;
833 	}
834 
835 	printf("/%lu/%lu", head, sect + 1);
836 }
837 
838 static void
839 print_mbr_partition(struct mbr_sector *boot, int part,
840     daddr_t offset, daddr_t exoffset, int indent)
841 {
842 	daddr_t	start;
843 	daddr_t	size;
844 	struct mbr_partition *partp = &boot->mbr_parts[part];
845 	struct mbr_sector eboot;
846 	int p;
847 	static int dumped = 0;
848 
849 	if (partp->mbrp_type == 0 && v_flag < 2) {
850 		printf("<UNUSED>\n");
851 		return;
852 	}
853 
854 	start = le32toh(partp->mbrp_start);
855 	size = le32toh(partp->mbrp_size);
856 	if (MBR_IS_EXTENDED(partp->mbrp_type))
857 		start += exoffset;
858 	else
859 		start += offset;
860 
861 	printf("%s (sysid %d)\n", get_type(partp->mbrp_type), partp->mbrp_type);
862 #ifdef BOOTSEL
863 	if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC &&
864 	    boot->mbr_bootsel.mbrbs_nametab[part][0])
865 		printf("%*s    bootmenu: %s\n", indent, "",
866 		    boot->mbr_bootsel.mbrbs_nametab[part]);
867 #endif
868 
869 	printf("%*s    start %"PRIdaddr", size %"PRIdaddr,
870 	    indent, "", start, size);
871 	if (size != 0) {
872 		printf(" (%u MB, Cyls ", SEC_TO_MB(size));
873 		if (v_flag == 0 && le32toh(partp->mbrp_start) == ptn_0_offset)
874 			pr_cyls(start - ptn_0_offset, 0);
875 		else
876 			pr_cyls(start, 0);
877 		printf("-");
878 		pr_cyls(start + size - 1, 1);
879 		printf(")");
880 	}
881 
882 	switch (partp->mbrp_flag) {
883 	case 0:
884 		break;
885 	case MBR_PFLAG_ACTIVE:
886 		printf(", Active");
887 		break;
888 	default:
889 		printf(", flag 0x%x", partp->mbrp_flag);
890 		break;
891 	}
892 	printf("\n");
893 
894 	if (v_flag) {
895 		printf("%*s        beg: cylinder %4d, head %3d, sector %2d\n",
896 		    indent, "",
897 		    MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect),
898 		    partp->mbrp_shd, MBR_PSECT(partp->mbrp_ssect));
899 		printf("%*s        end: cylinder %4d, head %3d, sector %2d\n",
900 		    indent, "",
901 		    MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect),
902 		    partp->mbrp_ehd, MBR_PSECT(partp->mbrp_esect));
903 	}
904 
905 	if (partp->mbrp_type == 0 && start == 0 && v_flag < 3)
906 		return;
907 
908 	if (! MBR_IS_EXTENDED(partp->mbrp_type))
909 		print_pbr(start, indent + 8, partp->mbrp_type);
910 
911 	if (!MBR_IS_EXTENDED(partp->mbrp_type) ||
912 	    (v_flag <= 2 && !ext.is_corrupt))
913 		return;
914 
915 	/*
916 	 * Recursive dump extended table,
917 	 * This is read from the disk - so is wrong during editing.
918 	 * Just ensure we only show it once.
919 	 */
920 	if (dumped)
921 		return;
922 
923 	printf("%*s    Extended partition table:\n", indent, "");
924 	indent += 4;
925 	if (read_s0(start, &eboot) == -1)
926 		return;
927 	for (p = 0; p < MBR_PART_COUNT; p++) {
928 		printf("%*s%d: ", indent, "", p);
929 		print_mbr_partition(&eboot, p, start,
930 				    exoffset ? exoffset : start, indent);
931 	}
932 
933 	if (exoffset == 0)
934 		dumped = 1;
935 }
936 
937 /* Print a line with a label and a vis-encoded string */
938 static void
939 printvis(int indent, const char *label, const char *buf, size_t size)
940 {
941 	char *visbuf;
942 
943 	if ((visbuf = malloc(size * 4 + 1)) == NULL)
944 		err(1, "Malloc failed");
945 	strsvisx(visbuf, buf, size, VIS_TAB|VIS_NL|VIS_OCTAL, "\"");
946 	printf("%*s%s: \"%s\"\n",
947 	    indent, "",
948 	    label, visbuf);
949 	free(visbuf);
950 }
951 
952 /* Check whether a buffer contains all bytes zero */
953 static int
954 is_all_zero(const unsigned char *p, size_t size)
955 {
956 
957 	while (size-- > 0) {
958 		if (*p++ != 0)
959 			return 0;
960 	}
961 	return 1;
962 }
963 
964 /*
965  * Report on the contents of a PBR sector.
966  *
967  * We first perform several sanity checks.  If vflag >= 2, we report all
968  * failing tests, but for smaller values of v_flag we stop after the
969  * first failing test.  Tests are ordered in an attempt to get the most
970  * useful error message from the first failing test.
971  *
972  * If v_flag >= 2, we also report some decoded values from the PBR.
973  * These results may be meaningless, if the PBR doesn't follow common
974  * conventions.
975  *
976  * Trying to decode anything more than the magic number in the last
977  * two bytes is a layering violation, but it can be very useful in
978  * diagnosing boot failures.
979  */
980 static void
981 print_pbr(daddr_t sector, int indent, uint8_t part_type)
982 {
983 	struct mbr_sector pboot;
984 	unsigned char *p, *endp;
985 	unsigned char val;
986 	int ok;
987 	int errcount = 0;
988 
989 #define PBR_ERROR(...)							\
990 	do {								\
991 		++errcount;						\
992 		printf("%*s%s: ", indent, "",				\
993 		    (v_flag < 2 ? "PBR is not bootable" : "Not bootable")); \
994 		printf(__VA_ARGS__);					\
995 		if (v_flag < 2)						\
996 			return;						\
997 	} while (/*CONSTCOND*/ 0)
998 
999 	if (v_flag >= 2) {
1000 		printf("%*sInformation from PBR:\n",
1001 		    indent, "");
1002 		indent += 4;
1003 	}
1004 
1005 	if (read_disk(sector, &pboot) == -1) {
1006 		PBR_ERROR("Sector %"PRIdaddr" is unreadable (%s)\n",
1007 		    sector, strerror(errno));
1008 		return;
1009 	}
1010 
1011 	/* all bytes identical? */
1012 	p = (unsigned char *)&pboot;
1013 	endp = p + sizeof(pboot);
1014 	val = *p;
1015 	ok = 0;
1016 	for (; p < endp; p++) {
1017 		if (*p != val) {
1018 			ok = 1;
1019 			break;
1020 		}
1021 	}
1022 	if (! ok)
1023 		PBR_ERROR("All bytes are identical (0x%02x)\n", val);
1024 
1025 	if (pboot.mbr_magic != LE_MBR_MAGIC)
1026 		PBR_ERROR("Bad magic number (0x%04x)\n",
1027 			le16toh(pboot.mbr_magic));
1028 
1029 #if 0
1030 	/* Some i386 OS might fail this test.  All non-i386 will fail. */
1031 	if (pboot.mbr_jmpboot[0] != 0xE9
1032 	    && pboot.mbr_jmpboot[0] != 0xEB) {
1033 		PBR_ERROR("Does not begin with i386 JMP instruction"
1034 			" (0x%02x 0x%02x0 0x%02x)\n",
1035 		    pboot.mbr_jmpboot[0], pboot.mbr_jmpboot[1],
1036 		    pboot.mbr_jmpboot[2]);
1037 	}
1038 #endif
1039 
1040 	if (v_flag > 0 && errcount == 0)
1041 		printf("%*sPBR appears to be bootable\n",
1042 		    indent, "");
1043 	if (v_flag < 2)
1044 		return;
1045 
1046 	if (! is_all_zero(pboot.mbr_oemname, sizeof(pboot.mbr_oemname))) {
1047 		printvis(indent, "OEM name", (char *)pboot.mbr_oemname,
1048 			sizeof(pboot.mbr_oemname));
1049 	}
1050 
1051 	if (pboot.mbr_bpb.bpb16.bsBootSig == 0x29)
1052 		printf("%*sBPB FAT16 boot signature found\n",
1053 		    indent, "");
1054 	if (pboot.mbr_bpb.bpb32.bsBootSig == 0x29)
1055 		printf("%*sBPB FAT32 boot signature found\n",
1056 		    indent, "");
1057 
1058 #undef PBR_ERROR
1059 }
1060 
1061 static int
1062 read_boot(const char *name, void *buf, size_t len, int err_exit)
1063 {
1064 	int bfd, ret;
1065 	struct stat st;
1066 
1067 	if (boot_path != NULL)
1068 		free(boot_path);
1069 	if (strchr(name, '/') == 0)
1070 		asprintf(&boot_path, "%s/%s", boot_dir, name);
1071 	else
1072 		boot_path = strdup(name);
1073 	if (boot_path == NULL)
1074 		err(1, "Malloc failed");
1075 
1076 	if ((bfd = open(boot_path, O_RDONLY)) < 0 || fstat(bfd, &st) == -1) {
1077 		warn("%s", boot_path);
1078 		goto fail;
1079 	}
1080 
1081 	if (st.st_size > (off_t)len) {
1082 		warnx("%s: bootcode too large", boot_path);
1083 		goto fail;
1084 	}
1085 	ret = st.st_size;
1086 	if (ret < 0x200) {
1087 		warnx("%s: bootcode too small", boot_path);
1088 		goto fail;
1089 	}
1090 	if (read(bfd, buf, len) != ret) {
1091 		warn("%s", boot_path);
1092 		goto fail;
1093 	}
1094 
1095 	/*
1096 	 * Do some sanity checking here
1097 	 */
1098 	if (((struct mbr_sector *)buf)->mbr_magic != LE_MBR_MAGIC) {
1099 		warnx("%s: invalid magic", boot_path);
1100 		goto fail;
1101 	}
1102 
1103 	close(bfd);
1104 	ret = (ret + 0x1ff) & ~0x1ff;
1105 	return ret;
1106 
1107     fail:
1108 	if (bfd >= 0)
1109 		close(bfd);
1110 	if (err_exit)
1111 		exit(1);
1112 	return 0;
1113 }
1114 
1115 static void
1116 init_sector0(int zappart)
1117 {
1118 	int i;
1119 	int copy_size = offsetof(struct mbr_sector, mbr_dsn);
1120 
1121 #ifdef DEFAULT_BOOTCODE
1122 	if (bootsize == 0)
1123 		bootsize = read_boot(DEFAULT_BOOTCODE, bootcode,
1124 			sizeof bootcode, 0);
1125 #endif
1126 #ifdef BOOTSEL
1127 	if (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC
1128 	    && bootcode[0].mbr_bootsel_magic == LE_MBR_BS_MAGIC)
1129 		copy_size = MBR_BS_OFFSET;
1130 #endif
1131 
1132 	if (bootsize != 0) {
1133 		boot_installed = 1;
1134 		memcpy(&mboot, bootcode, copy_size);
1135 		mboot.mbr_bootsel_magic = bootcode[0].mbr_bootsel_magic;
1136 	}
1137 	mboot.mbr_magic = LE_MBR_MAGIC;
1138 
1139 	if (!zappart)
1140 		return;
1141 	for (i = 0; i < MBR_PART_COUNT; i++)
1142 		memset(&mboot.mbr_parts[i], 0, sizeof(mboot.mbr_parts[i]));
1143 }
1144 
1145 static void
1146 get_extended_ptn(void)
1147 {
1148 	struct mbr_partition *mp;
1149 	struct mbr_sector *boot;
1150 	daddr_t offset;
1151 	struct mbr_sector *nptn;
1152 
1153 	/* find first (there should only be one) extended partition */
1154 	for (mp = mboot.mbr_parts; !MBR_IS_EXTENDED(mp->mbrp_type); mp++)
1155 		if (mp >= &mboot.mbr_parts[MBR_PART_COUNT])
1156 			return;
1157 
1158 	/*
1159 	 * The extended partition should be structured as a linked list
1160 	 * (even though it appears, at first glance, to be a tree).
1161 	 */
1162 	ext.base = le32toh(mp->mbrp_start);
1163 	ext.limit = ext.base + le32toh(mp->mbrp_size);
1164 	ext.ptn_id = mp - mboot.mbr_parts;
1165 	for (offset = 0;; offset = le32toh(boot->mbr_parts[1].mbrp_start)) {
1166 		nptn = realloc(ext.ptn, (ext.num_ptn + 1) * sizeof *ext.ptn);
1167 		if (nptn == NULL)
1168 			err(1, "Malloc failed");
1169 		ext.ptn = nptn;
1170 		boot = ext.ptn + ext.num_ptn;
1171 		if (read_s0(offset + ext.base, boot) == -1)
1172 			break;
1173 		/* expect p0 to be valid and p1 to be another extended ptn */
1174 		if (MBR_IS_EXTENDED(boot->mbr_parts[0].mbrp_type))
1175 			break;
1176 		if (boot->mbr_parts[1].mbrp_type != 0 &&
1177 		    !MBR_IS_EXTENDED(boot->mbr_parts[1].mbrp_type))
1178 			break;
1179 		/* p2 and p3 should be unallocated */
1180 		if (boot->mbr_parts[2].mbrp_type != 0 ||
1181 		    boot->mbr_parts[3].mbrp_type != 0)
1182 			break;
1183 		/* data ptn inside extended one */
1184 		if (boot->mbr_parts[0].mbrp_type != 0 &&
1185 		    offset + le32toh(boot->mbr_parts[0].mbrp_start)
1186 		    + le32toh(boot->mbr_parts[0].mbrp_size) > ext.limit)
1187 			break;
1188 
1189 		ext.num_ptn++;
1190 
1191 		if (boot->mbr_parts[1].mbrp_type == 0)
1192 			/* end of extended partition chain */
1193 			return;
1194 		/* must be in sector order */
1195 		if (offset >= le32toh(boot->mbr_parts[1].mbrp_start))
1196 			break;
1197 	}
1198 
1199 	warnx("Extended partition table is corrupt");
1200 	ext.is_corrupt = 1;
1201 	ext.num_ptn = 0;
1202 }
1203 
1204 #if defined(USE_DISKLIST)
1205 static void
1206 get_diskname(const char *fullname, char *diskname, size_t size)
1207 {
1208 	const char *p, *p2;
1209 	size_t len;
1210 
1211 	p = strrchr(fullname, '/');
1212 	if (p == NULL)
1213 		p = fullname;
1214 	else
1215 		p++;
1216 
1217 	if (*p == 0) {
1218 		strlcpy(diskname, fullname, size);
1219 		return;
1220 	}
1221 
1222 	if (*p == 'r')
1223 		p++;
1224 
1225 	for (p2 = p; *p2 != 0; p2++)
1226 		if (isdigit((unsigned char)*p2))
1227 			break;
1228 	if (*p2 == 0) {
1229 		/* XXX invalid diskname? */
1230 		strlcpy(diskname, fullname, size);
1231 		return;
1232 	}
1233 	while (isdigit((unsigned char)*p2))
1234 		p2++;
1235 
1236 	len = p2 - p;
1237 	if (len > size) {
1238 		/* XXX */
1239 		strlcpy(diskname, fullname, size);
1240 		return;
1241 	}
1242 
1243 	memcpy(diskname, p, len);
1244 	diskname[len] = 0;
1245 }
1246 #endif
1247 
1248 static void
1249 get_ptn_alignmemt(void)
1250 {
1251 	struct mbr_partition *partp = &mboot.mbr_parts[0];
1252 	uint32_t ptn_0_base, ptn_0_limit;
1253 
1254 	/* Default to using 'traditional' cylinder alignment */
1255 	ptn_alignment = dos_cylindersectors;
1256 	ptn_0_offset = dos_sectors;
1257 
1258 	if (partp->mbrp_type != 0) {
1259 		/* Try to copy alignment of first partition */
1260 		ptn_0_base = le32toh(partp->mbrp_start);
1261 		ptn_0_limit = ptn_0_base + le32toh(partp->mbrp_size);
1262 		if (!(ptn_0_limit & 2047)) {
1263 			/* Partition ends on a 1MB boundary, align to 1MB */
1264 			ptn_alignment = 2048;
1265 			if (ptn_0_base <= 2048
1266 			    && !(ptn_0_base & (ptn_0_base - 1))) {
1267 				/* ptn_base is a power of 2, use it */
1268 				ptn_0_offset = ptn_0_base;
1269 			}
1270 		}
1271 	} else {
1272 		/* Use 1MB alignment for large disks */
1273 		if (disksectors > 2048 * 1024 * 128) {
1274 			ptn_alignment = 2048;
1275 			ptn_0_offset = 2048;
1276 		}
1277 	}
1278 }
1279 
1280 static void
1281 get_bios_geometry(void)
1282 {
1283 #if defined(USE_DISKLIST)
1284 	int mib[2], i;
1285 	size_t len;
1286 	struct biosdisk_info *bip;
1287 	struct nativedisk_info *nip;
1288 	char diskname[8];
1289 
1290 	mib[0] = CTL_MACHDEP;
1291 	mib[1] = CPU_DISKINFO;
1292 	if (sysctl(mib, 2, NULL, &len, NULL, 0) < 0) {
1293 		goto out;
1294 	}
1295 	dl = (struct disklist *) malloc(len);
1296 	if (dl == NULL)
1297 		err(1, "Malloc failed");
1298 	if (sysctl(mib, 2, dl, &len, NULL, 0) < 0) {
1299 		free(dl);
1300 		dl = 0;
1301 		goto out;
1302 	}
1303 
1304 	get_diskname(disk, diskname, sizeof diskname);
1305 
1306 	for (i = 0; i < dl->dl_nnativedisks; i++) {
1307 		nip = &dl->dl_nativedisks[i];
1308 		if (strcmp(diskname, nip->ni_devname))
1309 			continue;
1310 		/*
1311 		 * XXX listing possible matches is better. This is ok for
1312 		 * now because the user has a chance to change it later.
1313 		 * Also, if all the disks have the same parameters then we can
1314 		 * just use them, we don't need to know which disk is which.
1315 		 */
1316 		if (nip->ni_nmatches != 0) {
1317 			bip = &dl->dl_biosdisks[nip->ni_biosmatches[0]];
1318 			dos_cylinders = bip->bi_cyl;
1319 			dos_heads = bip->bi_head;
1320 			dos_sectors = bip->bi_sec;
1321 			if (bip->bi_lbasecs)
1322 				dos_disksectors = bip->bi_lbasecs;
1323 			return;
1324 		}
1325 	}
1326  out:
1327 #endif
1328 	/* Allright, allright, make a stupid guess.. */
1329 	intuit_translated_geometry();
1330 }
1331 
1332 #ifdef BOOTSEL
1333 static daddr_t
1334 get_default_boot(void)
1335 {
1336 	unsigned int id;
1337 	int p;
1338 
1339 	if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1340 		/* default to first active partition */
1341 		return DEFAULT_ACTIVE;
1342 
1343 	id = mboot.mbr_bootsel.mbrbs_defkey;
1344 
1345 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ASCII) {
1346 		/* Keycode is ascii */
1347 		if (id == '\r')
1348 		    return DEFAULT_ACTIVE;
1349 		/* '1'+ => allocated partition id, 'a'+ => disk 0+ */
1350 		if (id >= 'a' && id < 'a' + MAX_BIOS_DISKS)
1351 			return DEFAULT_DISK(id - 'a');
1352 		id -= '1';
1353 	} else {
1354 		/* keycode is PS/2 keycode */
1355 		if (id == SCAN_ENTER)
1356 			return DEFAULT_ACTIVE;
1357 		/* 1+ => allocated partition id, F1+ => disk 0+ */
1358 		if (id >= SCAN_F1 && id < SCAN_F1 + MAX_BIOS_DISKS)
1359 			return DEFAULT_DISK(id - SCAN_F1);
1360 		id -= SCAN_1;
1361 	}
1362 
1363 	/* Convert partition index to the invariant start sector number */
1364 
1365 	for (p = 0; p < MBR_PART_COUNT; p++) {
1366 		if (mboot.mbr_parts[p].mbrp_type == 0)
1367 			continue;
1368 		if (mboot.mbr_bootsel.mbrbs_nametab[p][0] == 0)
1369 			continue;
1370 		if (id-- == 0)
1371 			return le32toh(mboot.mbr_parts[p].mbrp_start);
1372 	}
1373 
1374 	for (p = 0; p < ext.num_ptn; p++) {
1375 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1376 			continue;
1377 		if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1378 			continue;
1379 		if (id-- == 0)
1380 			return ext_offset(p)
1381 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start);
1382 	}
1383 
1384 	return DEFAULT_ACTIVE;
1385 }
1386 
1387 static void
1388 set_default_boot(daddr_t default_ptn)
1389 {
1390 	int p;
1391 	static const unsigned char key_list[] = { SCAN_ENTER, SCAN_F1, SCAN_1,
1392 						'\r', 'a', '1' };
1393 	const unsigned char *key = key_list;
1394 
1395 	if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1396 		/* sanity */
1397 		return;
1398 
1399 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ASCII)
1400 		/* Use ascii values */
1401 		key += 3;
1402 
1403 	if (default_ptn == DEFAULT_ACTIVE) {
1404 		mboot.mbr_bootsel.mbrbs_defkey = key[0];
1405 		return;
1406 	}
1407 
1408 	if (default_ptn >= DEFAULT_DISK(0)
1409 	    && default_ptn < DEFAULT_DISK(MAX_BIOS_DISKS)) {
1410 		mboot.mbr_bootsel.mbrbs_defkey = key[1]
1411 		    + default_ptn - DEFAULT_DISK(0);
1412 		return;
1413 	}
1414 
1415 	mboot.mbr_bootsel.mbrbs_defkey = key[2];
1416 	for (p = 0; p < MBR_PART_COUNT; p++) {
1417 		if (mboot.mbr_parts[p].mbrp_type == 0)
1418 			continue;
1419 		if (mboot.mbr_bootsel.mbrbs_nametab[p][0] == 0)
1420 			continue;
1421 		if (le32toh(mboot.mbr_parts[p].mbrp_start) == default_ptn)
1422 			return;
1423 		mboot.mbr_bootsel.mbrbs_defkey++;
1424 	}
1425 
1426 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_EXTLBA) {
1427 		for (p = 0; p < ext.num_ptn; p++) {
1428 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1429 				continue;
1430 			if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1431 				continue;
1432 			if (le32toh(ext.ptn[p].mbr_parts[0].mbrp_start) +
1433 			    ext_offset(p) == default_ptn)
1434 				return;
1435 			mboot.mbr_bootsel.mbrbs_defkey++;
1436 		}
1437 	}
1438 
1439 	/* Default to first active partition */
1440 	mboot.mbr_bootsel.mbrbs_defkey = key[0];
1441 }
1442 
1443 static void
1444 install_bootsel(int needed)
1445 {
1446 	struct mbr_bootsel *mbs = &mboot.mbr_bootsel;
1447 	int p;
1448 	int ext13 = 0;
1449 	const char *code;
1450 
1451 	needed |= MBR_BS_NEWMBR;	/* need new bootsel code */
1452 
1453 	/* Work out which boot code we need for this configuration */
1454 	for (p = 0; p < MBR_PART_COUNT; p++) {
1455 		if (mboot.mbr_parts[p].mbrp_type == 0)
1456 			continue;
1457 		if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1458 			break;
1459 		if (mbs->mbrbs_nametab[p][0] == 0)
1460 			continue;
1461 		needed |= MBR_BS_ACTIVE;
1462 		if (le32toh(mboot.mbr_parts[p].mbrp_start) >= dos_totalsectors)
1463 			ext13 = MBR_BS_EXTINT13;
1464 	}
1465 
1466 	for (p = 0; p < ext.num_ptn; p++) {
1467 		if (ext.ptn[p].mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1468 			continue;
1469 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1470 			continue;
1471 		if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[p][0] == 0)
1472 			continue;
1473 		needed |= MBR_BS_EXTLBA | MBR_BS_ACTIVE;
1474 	}
1475 
1476 	if (B_flag)
1477 		needed |= MBR_BS_ACTIVE;
1478 
1479 	/* Is the installed code good enough ? */
1480 	if (!i_flag && (needed == 0 ||
1481 	    (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC
1482 	    && (mbs->mbrbs_flags & needed) == needed))) {
1483 		/* yes - just set flags */
1484 		mbs->mbrbs_flags |= ext13;
1485 		return;
1486 	}
1487 
1488 	/* ok - we need to replace the bootcode */
1489 
1490 	if (f_flag && !(i_flag || B_flag)) {
1491 		warnx("Installed bootfile doesn't support required options.");
1492 		return;
1493 	}
1494 
1495 	if (!f_flag && bootsize == 0 && !i_flag)
1496 		/* Output an explanation for the 'update bootcode' prompt. */
1497 		printf("\n%s\n",
1498 		    "Installed bootfile doesn't support required options.");
1499 
1500 	/* Were we told a specific file ? (which we have already read) */
1501 	/* If so check that it supports what we need. */
1502 	if (bootsize != 0 && needed != 0
1503 	    && (bootcode[0].mbr_bootsel_magic != LE_MBR_BS_MAGIC
1504 	    || ((bootcode[0].mbr_bootsel.mbrbs_flags & needed) != needed))) {
1505 		/* No it doesn't... */
1506 		if (f_flag)
1507 			warnx("Bootfile %s doesn't support "
1508 				    "required bootsel options", boot_path );
1509 			/* But install it anyway */
1510 		else
1511 			if (yesno("Bootfile %s doesn't support the required "
1512 			    "options,\ninstall default bootfile instead?",
1513 			    boot_path))
1514 				bootsize = 0;
1515 	}
1516 
1517 	if (bootsize == 0) {
1518 		/* Get name of bootfile that supports the required facilities */
1519 		code = DEFAULT_BOOTCODE;
1520 		if (needed & MBR_BS_ACTIVE)
1521 			code = DEFAULT_BOOTSELCODE;
1522 #ifdef DEFAULT_BOOTEXTCODE
1523 		if (needed & MBR_BS_EXTLBA)
1524 			code = DEFAULT_BOOTEXTCODE;
1525 #endif
1526 
1527 		bootsize = read_boot(code, bootcode, sizeof bootcode, 0);
1528 		if (bootsize == 0)
1529 			/* The old bootcode is better than no bootcode at all */
1530 			return;
1531 		if ((bootcode[0].mbr_bootsel.mbrbs_flags & needed) != needed)
1532 			warnx("Default bootfile %s doesn't support required "
1533 				"options.  Got flags 0x%x, wanted 0x%x\n",
1534 				boot_path, bootcode[0].mbr_bootsel.mbrbs_flags,
1535 				needed);
1536 	}
1537 
1538 	if (!f_flag && !yesno("Update the bootcode from %s?", boot_path))
1539 		return;
1540 
1541 	init_sector0(0);
1542 
1543 	if (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC)
1544 		mbs->mbrbs_flags = bootcode[0].mbr_bootsel.mbrbs_flags | ext13;
1545 }
1546 
1547 static daddr_t
1548 configure_bootsel(daddr_t default_ptn)
1549 {
1550 	struct mbr_bootsel *mbs = &mboot.mbr_bootsel;
1551 	int i, item, opt;
1552 	int tmo;
1553 	daddr_t *off;
1554 	int num_bios_disks;
1555 
1556 #if defined(USE_DISKLIST)
1557 	if (dl != NULL) {
1558 		num_bios_disks = dl->dl_nbiosdisks;
1559 		if (num_bios_disks > MAX_BIOS_DISKS)
1560 			num_bios_disks = MAX_BIOS_DISKS;
1561 	} else
1562 #endif
1563 		num_bios_disks = MAX_BIOS_DISKS;
1564 
1565 	printf("\nBoot selector configuration:\n");
1566 
1567 	/* The timeout value is in ticks, ~18.2 Hz. Avoid using floats.
1568 	 * Ticks are nearly 64k/3600 - so our long timers are sligtly out!
1569 	 * Newer bootcode always waits for 1 tick, so treats 0xffff
1570 	 * as wait forever.
1571 	 */
1572 	tmo = le16toh(mbs->mbrbs_timeo);
1573 	tmo = tmo == 0xffff ? -1 : (10 * tmo + 9) / 182;
1574 	tmo = decimal("Timeout value (0 to 3600 seconds, -1 => never)",
1575 			tmo, 0, -1, 3600);
1576 	mbs->mbrbs_timeo = htole16(tmo == -1 ? 0xffff : (tmo * 182) / 10);
1577 
1578 	off = calloc(1 + MBR_PART_COUNT + ext.num_ptn + num_bios_disks, sizeof *off);
1579 	if (off == NULL)
1580 		err(1, "Malloc failed");
1581 
1582 	printf("Select the default boot option. Options are:\n\n");
1583 	item = 0;
1584 	opt = 0;
1585 	off[opt] = DEFAULT_ACTIVE;
1586 	printf("%d: The first active partition\n", opt);
1587 	for (i = 0; i < MBR_PART_COUNT; i++) {
1588 		if (mboot.mbr_parts[i].mbrp_type == 0)
1589 			continue;
1590 		if (mbs->mbrbs_nametab[i][0] == 0)
1591 			continue;
1592 		printf("%d: %s\n", ++opt, &mbs->mbrbs_nametab[i][0]);
1593 		off[opt] = le32toh(mboot.mbr_parts[i].mbrp_start);
1594 		if (off[opt] == default_ptn)
1595 			item = opt;
1596 	}
1597 	if (mbs->mbrbs_flags & MBR_BS_EXTLBA) {
1598 		for (i = 0; i < ext.num_ptn; i++) {
1599 			if (ext.ptn[i].mbr_parts[0].mbrp_type == 0)
1600 				continue;
1601 			if (ext.ptn[i].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1602 				continue;
1603 			printf("%d: %s\n",
1604 			    ++opt, ext.ptn[i].mbr_bootsel.mbrbs_nametab[0]);
1605 			off[opt] = ext_offset(i) +
1606 			    le32toh(ext.ptn[i].mbr_parts[0].mbrp_start);
1607 			if (off[opt] == default_ptn)
1608 				item = opt;
1609 		}
1610 	}
1611 	for (i = 0; i < num_bios_disks; i++) {
1612 		printf("%d: Harddisk %d\n", ++opt, i);
1613 		off[opt] = DEFAULT_DISK(i);
1614 		if (DEFAULT_DISK(i) == default_ptn)
1615 			item = opt;
1616 	}
1617 
1618 	item = decimal("Default boot option", item, 0, 0, opt);
1619 
1620 	default_ptn = off[item];
1621 	free(off);
1622 	return default_ptn;
1623 }
1624 #endif /* BOOTSEL */
1625 
1626 
1627 /* Prerequisite: the disklabel parameters and master boot record must
1628  *		 have been read (i.e. dos_* and mboot are meaningful).
1629  * Specification: modifies dos_cylinders, dos_heads, dos_sectors, and
1630  *		  dos_cylindersectors to be consistent with what the
1631  *		  partition table is using, if we can find a geometry
1632  *		  which is consistent with all partition table entries.
1633  *		  We may get the number of cylinders slightly wrong (in
1634  *		  the conservative direction).  The idea is to be able
1635  *		  to create a NetBSD partition on a disk we don't know
1636  *		  the translated geometry of.
1637  * This routine is only used for non-x86 systems or when we fail to
1638  * get the BIOS geometry from the kernel.
1639  */
1640 static void
1641 intuit_translated_geometry(void)
1642 {
1643 	uint32_t xcylinders;
1644 	int xheads = -1, xsectors = -1, i, j;
1645 	unsigned int c1, h1, s1, c2, h2, s2;
1646 	unsigned long a1, a2;
1647 	uint64_t num, denom;
1648 
1649 	/*
1650 	 * The physical parameters may be invalid as bios geometry.
1651 	 * If we cannot determine the actual bios geometry, we are
1652 	 * better off picking a likely 'faked' geometry than leaving
1653 	 * the invalid physical one.
1654 	 */
1655 
1656 	if (dos_cylinders > MAXCYL || dos_heads > MAXHEAD ||
1657 	    dos_sectors > MAXSECTOR) {
1658 		h1 = MAXHEAD - 1;
1659 		c1 = MAXCYL - 1;
1660 #if defined(USE_DISKLIST)
1661 		if (dl != NULL) {
1662 			/* BIOS may use 256 heads or 1024 cylinders */
1663 			for (i = 0; i < dl->dl_nbiosdisks; i++) {
1664 				if (h1 < (unsigned int)dl->dl_biosdisks[i].bi_head)
1665 					h1 = dl->dl_biosdisks[i].bi_head;
1666 				if (c1 < (unsigned int)dl->dl_biosdisks[i].bi_cyl)
1667 					c1 = dl->dl_biosdisks[i].bi_cyl;
1668 			}
1669 		}
1670 #endif
1671 		dos_sectors = MAXSECTOR;
1672 		dos_heads = h1;
1673 		dos_cylinders = disklabel.d_secperunit / (MAXSECTOR * h1);
1674 		if (dos_cylinders > c1)
1675 			dos_cylinders = c1;
1676 	}
1677 
1678 	/* Try to deduce the number of heads from two different mappings. */
1679 	for (i = 0; i < MBR_PART_COUNT * 2 - 1; i++) {
1680 		if (get_mapping(i, &c1, &h1, &s1, &a1) < 0)
1681 			continue;
1682 		a1 -= s1;
1683 		for (j = i + 1; j < MBR_PART_COUNT * 2; j++) {
1684 			if (get_mapping(j, &c2, &h2, &s2, &a2) < 0)
1685 				continue;
1686 			a2 -= s2;
1687 			num = (uint64_t)h1 * a2 - (uint64_t)h2 * a1;
1688 			denom = (uint64_t)c2 * a1 - (uint64_t)c1 * a2;
1689 			if (denom != 0 && num != 0 && num % denom == 0) {
1690 				xheads = num / denom;
1691 				xsectors = a1 / (c1 * xheads + h1);
1692 				break;
1693 			}
1694 		}
1695 		if (xheads != -1)
1696 			break;
1697 	}
1698 
1699 	if (xheads == -1) {
1700 		if (F_flag)
1701 			return;
1702 		warnx("Cannot determine the number of heads");
1703 		return;
1704 	}
1705 
1706 	if (xsectors == -1) {
1707 		warnx("Cannot determine the number of sectors");
1708 		return;
1709 	}
1710 
1711 	/* Estimate the number of cylinders. */
1712 	xcylinders = disklabel.d_secperunit / xheads / xsectors;
1713 	if (disklabel.d_secperunit > xcylinders * xheads * xsectors)
1714 		xcylinders++;
1715 
1716 	/*
1717 	 * Now verify consistency with each of the partition table entries.
1718 	 * Be willing to shove cylinders up a little bit to make things work,
1719 	 * but translation mismatches are fatal.
1720 	 */
1721 	for (i = 0; i < MBR_PART_COUNT * 2; i++) {
1722 		if (get_mapping(i, &c1, &h1, &s1, &a1) < 0)
1723 			continue;
1724 		if (c1 >= MAXCYL - 2)
1725 			continue;
1726 		if (xsectors * (c1 * xheads + h1) + s1 != a1)
1727 			return;
1728 	}
1729 
1730 
1731 	/* Everything checks out.
1732 	 * Reset the geometry to use for further calculations.
1733 	 * But cylinders cannot be > 1024.
1734 	 */
1735 	if (xcylinders > MAXCYL)
1736 		dos_cylinders = MAXCYL;
1737 	else
1738 		dos_cylinders = xcylinders;
1739 	dos_heads = xheads;
1740 	dos_sectors = xsectors;
1741 }
1742 
1743 /*
1744  * For the purposes of intuit_translated_geometry(), treat the partition
1745  * table as a list of eight mapping between (cylinder, head, sector)
1746  * triplets and absolute sectors.  Get the relevant geometry triplet and
1747  * absolute sectors for a given entry, or return -1 if it isn't present.
1748  * Note: for simplicity, the returned sector is 0-based.
1749  */
1750 static int
1751 get_mapping(int i, unsigned int *cylinder, unsigned int *head, unsigned int *sector,
1752     unsigned long *absolute)
1753 {
1754 	struct mbr_partition *part = &mboot.mbr_parts[i / 2];
1755 
1756 	if (part->mbrp_type == 0)
1757 		return -1;
1758 	if (i % 2 == 0) {
1759 		*cylinder = MBR_PCYL(part->mbrp_scyl, part->mbrp_ssect);
1760 		*head = part->mbrp_shd;
1761 		*sector = MBR_PSECT(part->mbrp_ssect);
1762 		*absolute = le32toh(part->mbrp_start);
1763 	} else {
1764 		*cylinder = MBR_PCYL(part->mbrp_ecyl, part->mbrp_esect);
1765 		*head = part->mbrp_ehd;
1766 		*sector = MBR_PSECT(part->mbrp_esect);
1767 		*absolute = le32toh(part->mbrp_start)
1768 		    + le32toh(part->mbrp_size) - 1;
1769 	}
1770 	/* Sanity check the data against all zeroes */
1771 	if ((*cylinder == 0) && (*sector == 0) && (*head == 0))
1772 		return -1;
1773 	/* sector numbers in the MBR partition table start at 1 */
1774 	*sector = *sector - 1;
1775 	/* Sanity check the data against max values */
1776 	if ((((*cylinder * MAXHEAD) + *head) * MAXSECTOR + *sector) < *absolute)
1777 		/* cannot be a CHS mapping */
1778 		return -1;
1779 	return 0;
1780 }
1781 
1782 static void
1783 delete_ptn(int part)
1784 {
1785 	if (part == ext.ptn_id) {
1786 		/* forget all about the extended partition */
1787 		free(ext.ptn);
1788 		memset(&ext, 0, sizeof ext);
1789 	}
1790 
1791 	mboot.mbr_parts[part].mbrp_type = 0;
1792 }
1793 
1794 static void
1795 delete_ext_ptn(int part)
1796 {
1797 
1798 	if (part == 0) {
1799 		ext.ptn[0].mbr_parts[0].mbrp_type = 0;
1800 		return;
1801 	}
1802 	ext.ptn[part - 1].mbr_parts[1] = ext.ptn[part].mbr_parts[1];
1803 	memmove(&ext.ptn[part], &ext.ptn[part + 1],
1804 		(ext.num_ptn - part - 1) * sizeof ext.ptn[0]);
1805 	ext.num_ptn--;
1806 }
1807 
1808 static int
1809 add_ext_ptn(daddr_t start, daddr_t size)
1810 {
1811 	int part;
1812 	struct mbr_partition *partp;
1813 	struct mbr_sector *nptn;
1814 
1815 	nptn = realloc(ext.ptn, (ext.num_ptn + 1) * sizeof *ext.ptn);
1816 	if (!nptn)
1817 		err(1, "realloc");
1818 	ext.ptn = nptn;
1819 	for (part = 0; part < ext.num_ptn; part++)
1820 		if (ext_offset(part) > start)
1821 			break;
1822 	/* insert before 'part' - make space... */
1823 	memmove(&ext.ptn[part + 1], &ext.ptn[part],
1824 		(ext.num_ptn - part) * sizeof ext.ptn[0]);
1825 	memset(&ext.ptn[part], 0, sizeof ext.ptn[0]);
1826 	ext.ptn[part].mbr_magic = LE_MBR_MAGIC;
1827 	/* we will be 'part' */
1828 	if (part == 0) {
1829 		/* link us to 'next' */
1830 		partp = &ext.ptn[0].mbr_parts[1];
1831 		/* offset will be fixed by caller */
1832 		partp->mbrp_size = htole32(
1833 		    le32toh(ext.ptn[1].mbr_parts[0].mbrp_start) +
1834 		    le32toh(ext.ptn[1].mbr_parts[0].mbrp_size));
1835 	} else {
1836 		/* link us to prev's next */
1837 		partp = &ext.ptn[part - 1].mbr_parts[1];
1838 		ext.ptn[part].mbr_parts[1] = *partp;
1839 		/* and prev onto us */
1840 		partp->mbrp_start = htole32(start - ptn_0_offset - ext.base);
1841 		partp->mbrp_size = htole32(size + ptn_0_offset);
1842 	}
1843 	partp->mbrp_type = 5;	/* as used by win98 */
1844 	partp->mbrp_flag = 0;
1845 	/* wallop in some CHS values - win98 doesn't saturate them */
1846 	dos(le32toh(partp->mbrp_start),
1847 	    &partp->mbrp_scyl, &partp->mbrp_shd, &partp->mbrp_ssect);
1848 	dos(le32toh(partp->mbrp_start) + le32toh(partp->mbrp_size) - 1,
1849 	    &partp->mbrp_ecyl, &partp->mbrp_ehd, &partp->mbrp_esect);
1850 	ext.num_ptn++;
1851 
1852 	return part;
1853 }
1854 
1855 static const char *
1856 check_overlap(int part, int sysid, daddr_t start, daddr_t size, int fix)
1857 {
1858 	int p;
1859 	unsigned int p_s, p_e;
1860 
1861 	if (sysid != 0) {
1862 		if (start == 0)
1863 			return "Sector zero is reserved for the MBR";
1864 #if 0
1865 		if (start < ptn_0_offset)
1866 			/* This is just a convention, not a requirement */
1867 			return "Track zero is reserved for the BIOS";
1868 #endif
1869 		if (start + size > disksectors)
1870 			return "Partition exceeds size of disk";
1871 		for (p = 0; p < MBR_PART_COUNT; p++) {
1872 			if (p == part || mboot.mbr_parts[p].mbrp_type == 0)
1873 				continue;
1874 			p_s = le32toh(mboot.mbr_parts[p].mbrp_start);
1875 			p_e = p_s + le32toh(mboot.mbr_parts[p].mbrp_size);
1876 			if (start + size <= p_s || start >= p_e)
1877 				continue;
1878 			if (f_flag) {
1879 				if (fix)
1880 					delete_ptn(p);
1881 				return 0;
1882 			}
1883 			return "Overlaps another partition";
1884 		}
1885 	}
1886 
1887 	/* Are we trying to create an extended partition */
1888 	if (!MBR_IS_EXTENDED(mboot.mbr_parts[part].mbrp_type)) {
1889 		/* this wasn't the extended partition */
1890 		if (!MBR_IS_EXTENDED(sysid))
1891 			return 0;
1892 		/* making an extended partition */
1893 		if (ext.base != 0) {
1894 			if (!f_flag)
1895 				return "There cannot be 2 extended partitions";
1896 			if (fix)
1897 				delete_ptn(ext.ptn_id);
1898 		}
1899 		if (fix) {
1900 			/* allocate a new extended partition */
1901 			ext.ptn = calloc(1, sizeof ext.ptn[0]);
1902 			if (ext.ptn == NULL)
1903 				err(1, "Malloc failed");
1904 			ext.ptn[0].mbr_magic = LE_MBR_MAGIC;
1905 			ext.ptn_id = part;
1906 			ext.base = start;
1907 			ext.limit = start + size;
1908 			ext.num_ptn = 1;
1909 		}
1910 		return 0;
1911 	}
1912 
1913 	/* Check we haven't cut space allocated to an extended ptn */
1914 
1915 	if (!MBR_IS_EXTENDED(sysid)) {
1916 		/* no longer an extended partition */
1917 		if (fix) {
1918 			/* Kill all memory of the extended partitions */
1919 			delete_ptn(part);
1920 			return 0;
1921 		}
1922 		if (ext.num_ptn == 0 ||
1923 		    (ext.num_ptn == 1 && ext.ptn[0].mbr_parts[0].mbrp_type == 0))
1924 			/* nothing in extended partition */
1925 			return 0;
1926 		if (f_flag)
1927 			return 0;
1928 		if (yesno("Do you really want to delete all the extended partitions?"))
1929 			return 0;
1930 		return "Extended partition busy";
1931 	}
1932 
1933 	if (le32toh(mboot.mbr_parts[part].mbrp_start) != ext.base)
1934 		/* maybe impossible, but an extra sanity check */
1935 		return 0;
1936 
1937 	for (p = ext.num_ptn; --p >= 0;) {
1938 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1939 			continue;
1940 		p_s = ext_offset(p);
1941 		p_e = p_s + le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
1942 			  + le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
1943 		if (p_s >= start && p_e <= start + size)
1944 			continue;
1945 		if (!f_flag)
1946 			return "Extended partition outside main partition";
1947 		if (fix)
1948 			delete_ext_ptn(p);
1949 	}
1950 
1951 	if (fix && start != ext.base) {
1952 		/* The internal offsets need to be fixed up */
1953 		for (p = 0; p < ext.num_ptn - 1; p++)
1954 			ext.ptn[p].mbr_parts[1].mbrp_start = htole32(
1955 			    le32toh(ext.ptn[p].mbr_parts[1].mbrp_start)
1956 				    + ext.base - start);
1957 		/* and maybe an empty partition at the start */
1958 		if (ext.ptn[0].mbr_parts[0].mbrp_type == 0) {
1959 			if (le32toh(ext.ptn[0].mbr_parts[1].mbrp_start) == 0) {
1960 				/* don't need the empty slot */
1961 				memmove(&ext.ptn[0], &ext.ptn[1],
1962 					(ext.num_ptn - 1) * sizeof ext.ptn[0]);
1963 				ext.num_ptn--;
1964 			}
1965 		} else {
1966 			/* must create an empty slot */
1967 			add_ext_ptn(start, ptn_0_offset);
1968 			ext.ptn[0].mbr_parts[1].mbrp_start = htole32(ext.base
1969 								- start);
1970 		}
1971 	}
1972 	if (fix) {
1973 		ext.base = start;
1974 		ext.limit = start + size;
1975 	}
1976 	return 0;
1977 }
1978 
1979 static const char *
1980 check_ext_overlap(int part, int sysid, daddr_t start, daddr_t size, int fix)
1981 {
1982 	int p;
1983 	unsigned int p_s, p_e;
1984 
1985 	if (sysid == 0)
1986 		return 0;
1987 
1988 	if (MBR_IS_EXTENDED(sysid))
1989 		return "Nested extended partitions are not allowed";
1990 
1991 	/* allow one track at start for extended partition header */
1992 	start -= ptn_0_offset;
1993 	size += ptn_0_offset;
1994 	if (start < ext.base || start + size > ext.limit)
1995 		return "Outside bounds of extended partition";
1996 
1997 	if (f_flag && !fix)
1998 		return 0;
1999 
2000 	for (p = ext.num_ptn; --p >= 0;) {
2001 		if (p == part || ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2002 			continue;
2003 		p_s = ext_offset(p);
2004 		p_e = p_s + le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2005 			+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
2006 		if (p == 0)
2007 			p_s += le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2008 							- ptn_0_offset;
2009 		if (start < p_e && start + size > p_s) {
2010 			if (!f_flag)
2011 				return "Overlaps another extended partition";
2012 			if (fix) {
2013 				if (part == -1)
2014 					delete_ext_ptn(p);
2015 				else
2016 					/* must not change numbering yet */
2017 					ext.ptn[p].mbr_parts[0].mbrp_type = 0;
2018 			}
2019 		}
2020 	}
2021 	return 0;
2022 }
2023 
2024 static int
2025 change_part(int extended, int part, int sysid, daddr_t start, daddr_t size,
2026 	char *bootmenu)
2027 {
2028 	struct mbr_partition *partp;
2029 	struct mbr_sector *boot;
2030 	daddr_t offset;
2031 	const char *e;
2032 	int upart = part;
2033 	int p;
2034 	int fl;
2035 	daddr_t n_s, n_e;
2036 	const char *errtext;
2037 #ifdef BOOTSEL
2038 	char tmp_bootmenu[MBR_PART_COUNT * (MBR_BS_PARTNAMESIZE + 1)];
2039 	int bootmenu_len = (extended ? MBR_PART_COUNT : 1) * (MBR_BS_PARTNAMESIZE + 1);
2040 #endif
2041 
2042 	if (extended) {
2043 		if (part != -1 && part < ext.num_ptn) {
2044 			boot = &ext.ptn[part];
2045 			partp = &boot->mbr_parts[0];
2046 			offset = ext_offset(part);
2047 		} else {
2048 			part = -1;
2049 			boot = 0;
2050 			partp = 0;
2051 			offset = 0;
2052 		}
2053 		upart = 0;
2054 		e = "E";
2055 	} else {
2056 		boot = &mboot;
2057 		partp = &boot->mbr_parts[part];
2058 		offset = 0;
2059 		e = "";
2060 	}
2061 
2062 	if (!f_flag && part != -1) {
2063 		printf("The data for partition %s%d is:\n", e, part);
2064 		print_part(boot, upart, offset);
2065 	}
2066 
2067 #ifdef BOOTSEL
2068 	if (bootmenu != NULL)
2069 		strlcpy(tmp_bootmenu, bootmenu, bootmenu_len);
2070 	else
2071 		if (boot != NULL && boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC)
2072 			strlcpy(tmp_bootmenu,
2073 				boot->mbr_bootsel.mbrbs_nametab[upart],
2074 				bootmenu_len);
2075 		else
2076 			tmp_bootmenu[0] = 0;
2077 #endif
2078 
2079 	if (partp != NULL) {
2080 		if (!s_flag) {
2081 			/* values not specified, default to current ones */
2082 			sysid = partp->mbrp_type;
2083 			start = offset + le32toh(partp->mbrp_start);
2084 			size = le32toh(partp->mbrp_size);
2085 		} else {
2086 			if (sysid == -1)
2087 				sysid = partp->mbrp_type;
2088 			if (start == (daddr_t)0xffffffff) {
2089 				start = offset + le32toh(partp->mbrp_start);
2090 				if (start == 0)
2091 					start = offset = ptn_0_offset;
2092 			}
2093 			if (size == (daddr_t)0xffffffff) {
2094 				size = le32toh(partp->mbrp_size);
2095 				if (size == 0)
2096 					size = disksectors - start;
2097 			}
2098 		}
2099 	}
2100 
2101 	/* creating a new partition, default to free space */
2102 	if (!s_flag && sysid == 0 && extended) {
2103 		/* non-extended partition */
2104 		start = ext.base;
2105 		for (p = 0; p < ext.num_ptn; p++) {
2106 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2107 				continue;
2108 			n_s = ext_offset(p);
2109 			if (n_s > start + ptn_0_offset)
2110 				break;
2111 			start = ext_offset(p)
2112 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2113 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
2114 		}
2115 		if (ext.limit - start <= ptn_0_offset) {
2116 			printf("No space in extended partition\n");
2117 			return 0;
2118 		}
2119 		start += ptn_0_offset;
2120 	}
2121 
2122 	if (!s_flag && sysid == 0 && !extended) {
2123 		/* same for non-extended partition */
2124 		/* first see if old start is free */
2125 		if (start < ptn_0_offset)
2126 			start = 0;
2127 		for (p = 0; start != 0 && p < MBR_PART_COUNT; p++) {
2128 			if (mboot.mbr_parts[p].mbrp_type == 0)
2129 				continue;
2130 			n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2131 			if (start >= n_s &&
2132 			    start < n_s + le32toh(mboot.mbr_parts[p].mbrp_size))
2133 				start = 0;
2134 		}
2135 		if (start == 0) {
2136 			/* Look for first gap */
2137 			start = ptn_0_offset;
2138 			for (p = 0; p < MBR_PART_COUNT; p++) {
2139 				if (mboot.mbr_parts[p].mbrp_type == 0)
2140 					continue;
2141 				n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2142 				n_e = n_s + le32toh(mboot.mbr_parts[p].mbrp_size);
2143 				if (start >= n_s && start < n_e) {
2144 					start = n_e;
2145 					p = -1;
2146 				}
2147 			}
2148 			if (start >= disksectors && !I_flag) {
2149 				printf("No free space\n");
2150 				return 0;
2151 			}
2152 		}
2153 	}
2154 
2155 	if (!f_flag) {
2156 		/* request new values from user */
2157 		if (sysid == 0)
2158 			sysid = 169;
2159 		sysid = decimal("sysid", sysid, 0, 0, 255);
2160 		if (sysid == 0 && !v_flag) {
2161 			start = 0;
2162 			size = 0;
2163 #ifdef BOOTSEL
2164 			tmp_bootmenu[0] = 0;
2165 #endif
2166 		} else {
2167 			daddr_t old = start;
2168 			daddr_t lim = extended ? ext.limit : disksectors;
2169 			start = decimal("start", start,
2170 				DEC_SEC | DEC_RND_0 | (extended ? DEC_RND : 0),
2171 				extended ? ext.base : 0, lim);
2172 			/* Adjust 'size' so that end doesn't move when 'start'
2173 			 * is only changed slightly.
2174 			 */
2175 			if (size > start - old)
2176 				size -= start - old;
2177 			else
2178 				size = 0;
2179 			/* Find end of available space from this start point */
2180 			if (extended) {
2181 				for (p = 0; p < ext.num_ptn; p++) {
2182 					if (p == part)
2183 						continue;
2184 					if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2185 						continue;
2186 					n_s = ext_offset(p);
2187 					if (n_s > start && n_s < lim)
2188 						lim = n_s;
2189 					if (start >= n_s && start < n_s
2190 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2191 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size)) {
2192 						lim = start;
2193 						break;
2194 					}
2195 				}
2196 			} else {
2197 				for (p = 0; p < MBR_PART_COUNT; p++) {
2198 					if (p == part)
2199 						continue;
2200 					if (mboot.mbr_parts[p].mbrp_type == 0)
2201 						continue;
2202 					n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2203 					if (n_s > start && n_s < lim)
2204 						lim = n_s;
2205 					if (start >= n_s && start < n_s
2206 				    + le32toh(mboot.mbr_parts[p].mbrp_size)) {
2207 						lim = start;
2208 						break;
2209 					}
2210 				}
2211 			}
2212 			lim -= start;
2213 			if (lim == 0) {
2214 				printf("Start sector already allocated\n");
2215 				return 0;
2216 			}
2217 			if (size == 0 || size > lim)
2218 				size = lim;
2219 			fl = DEC_SEC;
2220 			if (start % ptn_alignment == ptn_0_offset)
2221 				fl |= DEC_RND_DOWN;
2222 			if (start == 2 * ptn_0_offset)
2223 				fl |= DEC_RND_DOWN | DEC_RND_DOWN_2;
2224 			size = decimal("size", size, fl, 0, lim);
2225 #ifdef BOOTSEL
2226 #ifndef DEFAULT_BOOTEXTCODE
2227 			if (!extended)
2228 #endif
2229 				string("bootmenu", bootmenu_len, tmp_bootmenu);
2230 #endif
2231 		}
2232 	}
2233 
2234 	/*
2235 	 * Before we write these away, we must verify that nothing
2236 	 * untoward has been requested.
2237 	 */
2238 
2239 	if (extended)
2240 		errtext = check_ext_overlap(part, sysid, start, size, 0);
2241 	else
2242 		errtext = check_overlap(part, sysid, start, size, 0);
2243 	if (errtext != NULL && !I_flag) {
2244 		if (f_flag)
2245 			errx(2, "%s", errtext);
2246 		printf("%s\n", errtext);
2247 		return 0;
2248 	}
2249 
2250 	/*
2251 	 * Before proceeding, delete any overlapped partitions.
2252 	 * This can only happen if '-f' was supplied on the command line.
2253 	 * Just hope the caller knows what they are doing.
2254 	 * This also fixes the base of each extended partition if the
2255 	 * partition itself has moved.
2256 	 */
2257 	if (!I_flag) {
2258 		if (extended)
2259 			errtext = check_ext_overlap(part, sysid, start, size, 1);
2260 		else
2261 			errtext = check_overlap(part, sysid, start, size, 1);
2262 		if (errtext)
2263 			errx(1, "%s", errtext);
2264 	}
2265 
2266 
2267 	if (sysid == 0) {
2268 		/* delete this partition - save info though */
2269 		if (partp == NULL)
2270 			/* must have been trying to create an extended ptn */
2271 			return 0;
2272 		if (start == 0 && size == 0)
2273 			memset(partp, 0, sizeof *partp);
2274 #ifdef BOOTSEL
2275 		if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC)
2276 			memset(boot->mbr_bootsel.mbrbs_nametab[upart], 0,
2277 				sizeof boot->mbr_bootsel.mbrbs_nametab[0]);
2278 #endif
2279 		if (extended)
2280 			delete_ext_ptn(part);
2281 		else
2282 			delete_ptn(part);
2283 		return 1;
2284 	}
2285 
2286 
2287 	if (extended) {
2288 		if (part != -1)
2289 			delete_ext_ptn(part);
2290 		if (start == ext.base + ptn_0_offset)
2291 			/* First one must have been free */
2292 			part = 0;
2293 		else
2294 			part = add_ext_ptn(start, size);
2295 
2296 		/* These must be re-calculated because of the realloc */
2297 		boot = &ext.ptn[part];
2298 		partp = &boot->mbr_parts[0];
2299 		offset = ext_offset(part);
2300 	}
2301 
2302 	partp->mbrp_type = sysid;
2303 	partp->mbrp_start = htole32( start - offset);
2304 	partp->mbrp_size = htole32( size);
2305 	dos(start, &partp->mbrp_scyl, &partp->mbrp_shd, &partp->mbrp_ssect);
2306 	dos(start + size - 1,
2307 		    &partp->mbrp_ecyl, &partp->mbrp_ehd, &partp->mbrp_esect);
2308 #ifdef BOOTSEL
2309 	if (extended) {
2310 		boot->mbr_bootsel_magic = LE_MBR_BS_MAGIC;
2311 		strncpy(boot->mbr_bootsel.mbrbs_nametab[upart], tmp_bootmenu,
2312 			bootmenu_len);
2313 	} else {
2314 		/* We need to bootselect code installed in order to have
2315 		 * somewhere to safely write the menu tag.
2316 		 */
2317 		if (boot->mbr_bootsel_magic != LE_MBR_BS_MAGIC) {
2318 			if (f_flag ||
2319 			    yesno("The bootselect code is not installed, "
2320 				"do you want to install it now?"))
2321 				install_bootsel(MBR_BS_ACTIVE);
2322 		}
2323 		if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
2324 			strncpy(boot->mbr_bootsel.mbrbs_nametab[upart],
2325 				tmp_bootmenu, bootmenu_len);
2326 		}
2327 	}
2328 #endif
2329 
2330 	if (v_flag && !f_flag && yesno("Explicitly specify beg/end address?")) {
2331 		/* this really isn't a good idea.... */
2332 		int tsector, tcylinder, thead;
2333 
2334 		tcylinder = MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect);
2335 		thead = partp->mbrp_shd;
2336 		tsector = MBR_PSECT(partp->mbrp_ssect);
2337 		tcylinder = decimal("beginning cylinder",
2338 				tcylinder, 0, 0, dos_cylinders - 1);
2339 		thead = decimal("beginning head",
2340 				thead, 0, 0, dos_heads - 1);
2341 		tsector = decimal("beginning sector",
2342 				tsector, 0, 1, dos_sectors);
2343 		partp->mbrp_scyl = DOSCYL(tcylinder);
2344 		partp->mbrp_shd = thead;
2345 		partp->mbrp_ssect = DOSSECT(tsector, tcylinder);
2346 
2347 		tcylinder = MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect);
2348 		thead = partp->mbrp_ehd;
2349 		tsector = MBR_PSECT(partp->mbrp_esect);
2350 		tcylinder = decimal("ending cylinder",
2351 				tcylinder, 0, 0, dos_cylinders - 1);
2352 		thead = decimal("ending head",
2353 				thead, 0, 0, dos_heads - 1);
2354 		tsector = decimal("ending sector",
2355 				tsector, 0, 1, dos_sectors);
2356 		partp->mbrp_ecyl = DOSCYL(tcylinder);
2357 		partp->mbrp_ehd = thead;
2358 		partp->mbrp_esect = DOSSECT(tsector, tcylinder);
2359 	}
2360 
2361 	/* If we had to mark an extended partition as deleted because
2362 	 * another request would have overlapped it, now is the time
2363 	 * to do the actual delete.
2364 	 */
2365 	if (extended && f_flag) {
2366 		for (p = ext.num_ptn; --p >= 0;)
2367 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2368 				delete_ext_ptn(p);
2369 	}
2370 	return 1;
2371 }
2372 
2373 static void
2374 print_geometry(void)
2375 {
2376 
2377 	if (sh_flag) {
2378 		printf("DISK=%s\n", disk);
2379 		printf("DLCYL=%d\nDLHEAD=%d\nDLSEC=%d\nDLSIZE=%"PRIdaddr"\n",
2380 			cylinders, heads, sectors, disksectors);
2381 		printf("BCYL=%d\nBHEAD=%d\nBSEC=%d\nBDLSIZE=%"PRIdaddr"\n",
2382 			dos_cylinders, dos_heads, dos_sectors, dos_disksectors);
2383 		printf("NUMEXTPTN=%d\n", ext.num_ptn);
2384 		return;
2385 	}
2386 
2387 	/* Not sh_flag */
2388 	printf("Disk: %s\n", disk);
2389 	printf("NetBSD disklabel disk geometry:\n");
2390 	printf("cylinders: %d, heads: %d, sectors/track: %d "
2391 	    "(%d sectors/cylinder)\ntotal sectors: %"PRIdaddr", "
2392 	    "bytes/sector: %zd\n\n", cylinders, heads, sectors,
2393 	    cylindersectors, disksectors, secsize);
2394 	printf("BIOS disk geometry:\n");
2395 	printf("cylinders: %d, heads: %d, sectors/track: %d "
2396 	    "(%d sectors/cylinder)\ntotal sectors: %"PRIdaddr"\n\n",
2397 	    dos_cylinders, dos_heads, dos_sectors, dos_cylindersectors,
2398 	    dos_disksectors);
2399 	printf("Partitions aligned to %d sector boundaries, offset %d\n\n",
2400 	    ptn_alignment, ptn_0_offset);
2401 }
2402 
2403 /* Find the first active partition, else return MBR_PART_COUNT */
2404 static int
2405 first_active(void)
2406 {
2407 	struct mbr_partition *partp = &mboot.mbr_parts[0];
2408 	int part;
2409 
2410 	for (part = 0; part < MBR_PART_COUNT; part++)
2411 		if (partp[part].mbrp_flag & MBR_PFLAG_ACTIVE)
2412 			return part;
2413 	return MBR_PART_COUNT;
2414 }
2415 
2416 static void
2417 change_active(int which)
2418 {
2419 	struct mbr_partition *partp;
2420 	int part;
2421 	int active = MBR_PART_COUNT;
2422 
2423 	partp = &mboot.mbr_parts[0];
2424 
2425 	if (a_flag && which != -1)
2426 		active = which;
2427 	else
2428 		active = first_active();
2429 	if (!f_flag) {
2430 		if (yesno("Do you want to change the active partition?")) {
2431 			printf ("Choosing %d will make no partition active.\n",
2432 			    MBR_PART_COUNT);
2433 			do {
2434 				active = decimal("active partition",
2435 						active, 0, 0, MBR_PART_COUNT);
2436 			} while (!yesno("Are you happy with this choice?"));
2437 		} else
2438 			return;
2439 	} else
2440 		if (active != MBR_PART_COUNT)
2441 			printf ("Making partition %d active.\n", active);
2442 
2443 	for (part = 0; part < MBR_PART_COUNT; part++)
2444 		partp[part].mbrp_flag &= ~MBR_PFLAG_ACTIVE;
2445 	if (active < MBR_PART_COUNT)
2446 		partp[active].mbrp_flag |= MBR_PFLAG_ACTIVE;
2447 }
2448 
2449 static void
2450 change_bios_geometry(void)
2451 {
2452 	print_geometry();
2453 	if (!yesno("Do you want to change our idea of what BIOS thinks?"))
2454 		return;
2455 
2456 #if defined(USE_DISKLIST)
2457 	if (dl != NULL) {
2458 		struct biosdisk_info *bip;
2459 		int i;
2460 
2461 		for (i = 0; i < dl->dl_nbiosdisks; i++) {
2462 			if (i == 0)
2463 				printf("\nGeometries of known disks:\n");
2464 			bip = &dl->dl_biosdisks[i];
2465 			printf("Disk %d: cylinders %u, heads %u, sectors %u"
2466 				" (%"PRIdaddr" sectors, %dMB)\n",
2467 			    i, bip->bi_cyl, bip->bi_head, bip->bi_sec,
2468 			    bip->bi_lbasecs, SEC_TO_MB(bip->bi_lbasecs));
2469 
2470 		}
2471 		printf("\n");
2472 	}
2473 #endif
2474 	do {
2475 		dos_cylinders = decimal("BIOS's idea of #cylinders",
2476 					dos_cylinders, 0, 0, MAXCYL);
2477 		dos_heads = decimal("BIOS's idea of #heads",
2478 					dos_heads, 0, 0, MAXHEAD);
2479 		dos_sectors = decimal("BIOS's idea of #sectors",
2480 					dos_sectors, 0, 1, MAXSECTOR);
2481 		print_geometry();
2482 	} while (!yesno("Are you happy with this choice?"));
2483 }
2484 
2485 
2486 /***********************************************\
2487 * Change real numbers into strange dos numbers	*
2488 \***********************************************/
2489 static void
2490 dos(int sector, unsigned char *cylinderp, unsigned char *headp,
2491     unsigned char *sectorp)
2492 {
2493 	int cylinder, head;
2494 
2495 	cylinder = sector / dos_cylindersectors;
2496 	sector -= cylinder * dos_cylindersectors;
2497 
2498 	head = sector / dos_sectors;
2499 	sector -= head * dos_sectors;
2500 	if (cylinder > 1023)
2501 		cylinder = 1023;
2502 
2503 	*cylinderp = DOSCYL(cylinder);
2504 	*headp = head;
2505 	*sectorp = DOSSECT(sector + 1, cylinder);
2506 }
2507 
2508 static int
2509 open_disk(int update)
2510 {
2511 	static char namebuf[MAXPATHLEN + 1];
2512 	int flags = update && disk_file == NULL ? O_RDWR : O_RDONLY;
2513 
2514 	if (!F_flag) {
2515 		fd = opendisk(disk, flags, namebuf, sizeof(namebuf), 0);
2516 		if (fd < 0) {
2517 			if (errno == ENODEV)
2518 				warnx("%s is not a character device", namebuf);
2519 			else
2520 				warn("cannot opendisk %s", namebuf);
2521 			return (-1);
2522 		}
2523 		disk = namebuf;
2524 	} else {
2525 		fd = open(disk, flags, 0);
2526 		if (fd == -1) {
2527 			warn("cannot open %s", disk);
2528 			return -1;
2529 		}
2530 	}
2531 
2532 	if (get_params() == -1) {
2533 		close(fd);
2534 		fd = -1;
2535 		return (-1);
2536 	}
2537 	if (disk_file != NULL) {
2538 		/* for testing: read/write data from a disk file */
2539 		wfd = open(disk_file, update ? O_RDWR|O_CREAT : O_RDONLY, 0777);
2540 		if (wfd == -1) {
2541 			warn("%s", disk_file);
2542 			close(fd);
2543 			fd = -1;
2544 			return -1;
2545 		}
2546 	} else
2547 		wfd = fd;
2548 	return (0);
2549 }
2550 
2551 static ssize_t
2552 read_disk(daddr_t sector, void *buf)
2553 {
2554 	ssize_t nr;
2555 
2556 	if (*rfd == -1)
2557 		errx(1, "read_disk(); fd == -1");
2558 
2559 	off_t offs = sector * (off_t)secsize;
2560 	off_t mod = offs & (secsize - 1);
2561 	off_t rnd = offs & ~(secsize - 1);
2562 
2563 	if (lseek(*rfd, rnd, SEEK_SET) == (off_t)-1)
2564 		return -1;
2565 
2566 	if (secsize == 512)
2567 		return read(*rfd, buf, 512);
2568 
2569 	if ((nr = read(*rfd, iobuf, secsize)) != secsize)
2570 		return nr;
2571 
2572 	memcpy(buf, &iobuf[mod], 512);
2573 
2574 	return 512;
2575 }
2576 
2577 static ssize_t
2578 write_disk(daddr_t sector, void *buf)
2579 {
2580 	ssize_t nr;
2581 
2582 	if (wfd == -1)
2583 		errx(1, "write_disk(); wfd == -1");
2584 
2585 	off_t offs = sector * (off_t)secsize;
2586 	off_t mod = offs & (secsize - 1);
2587 	off_t rnd = offs & ~(secsize - 1);
2588 
2589 	if (lseek(wfd, rnd, SEEK_SET) == (off_t)-1)
2590 		return -1;
2591 
2592 	if (secsize == 512)
2593 		return write(wfd, buf, 512);
2594 
2595 	if ((nr = read(wfd, iobuf, secsize)) != secsize)
2596 		return nr;
2597 
2598 	if (lseek(wfd, rnd, SEEK_SET) == (off_t)-1)
2599 		return -1;
2600 
2601 	memcpy(&iobuf[mod], buf, 512);
2602 
2603 	if ((nr = write(wfd, iobuf, secsize)) != secsize)
2604 		return nr;
2605 
2606 	return 512;
2607 }
2608 
2609 static void
2610 guess_geometry(daddr_t _sectors)
2611 {
2612 	dos_sectors = MAXSECTOR;
2613 	dos_heads = MAXHEAD - 1;	/* some BIOS might use 256 */
2614 	dos_cylinders = _sectors / (MAXSECTOR * (MAXHEAD - 1));
2615 	if (dos_cylinders < 1)
2616 		dos_cylinders = 1;
2617 	else if (dos_cylinders > MAXCYL - 1)
2618 		dos_cylinders = MAXCYL - 1;
2619 }
2620 
2621 static int
2622 get_params(void)
2623 {
2624 	if (disk_type != NULL) {
2625 		struct disklabel *tmplabel;
2626 
2627 		if ((tmplabel = getdiskbyname(disk_type)) == NULL) {
2628 			warn("%s: bad disktype", disk);
2629 			return (-1);
2630 		}
2631 		disklabel = *tmplabel;
2632 	} else if (F_flag) {
2633 		struct stat st;
2634 		if (fstat(fd, &st) == -1) {
2635 			warn("%s: fstat", disk);
2636 			return (-1);
2637 		}
2638 		if (st.st_size % 512 != 0) {
2639 			warnx("%s size (%ju) is not divisible "
2640 			    "by sector size (%d)", disk, (uintmax_t)st.st_size,
2641 			    512);
2642 		}
2643 		disklabel.d_secperunit = st.st_size / 512;
2644 		guess_geometry(disklabel.d_secperunit);
2645 		disklabel.d_ncylinders = dos_cylinders;
2646 		disklabel.d_ntracks = dos_heads;
2647 		disklabel.d_secsize = 512;
2648 		disklabel.d_nsectors = dos_sectors;
2649 	}
2650 #if !HAVE_NBTOOL_CONFIG_H
2651 	else if (ioctl(fd, DIOCGDEFLABEL, &disklabel) == -1) {
2652 		warn("%s: DIOCGDEFLABEL", disk);
2653 		if (ioctl(fd, DIOCGDINFO, &disklabel) == -1) {
2654 			warn("%s: DIOCGDINFO", disk);
2655 			return (-1);
2656 		}
2657 	}
2658 #endif
2659 
2660 	disksectors = disklabel.d_secperunit;
2661 	cylinders = disklabel.d_ncylinders;
2662 	heads = disklabel.d_ntracks;
2663 	secsize = disklabel.d_secsize;
2664 	sectors = disklabel.d_nsectors;
2665 
2666 	/* pick up some defaults for the BIOS sizes */
2667 	if (sectors <= MAXSECTOR) {
2668 		dos_cylinders = cylinders;
2669 		dos_heads = heads;
2670 		dos_sectors = sectors;
2671 	} else {
2672 		/* guess - has to better than the above */
2673 		guess_geometry(disksectors);
2674 	}
2675 	dos_disksectors = disksectors;
2676 
2677 	return (0);
2678 }
2679 
2680 #ifdef BOOTSEL
2681 /*
2682  * Rather unfortunately the bootsel 'magic' number is at the end of the
2683  * the structure, and there is no checksum.  So when other operating
2684  * systems install mbr code by only writing the length of their code they
2685  * can overwrite part of the structure but keeping the magic number intact.
2686  * This code attempts to empirically detect this problem.
2687  */
2688 static int
2689 validate_bootsel(struct mbr_bootsel *mbs)
2690 {
2691 	unsigned int key = mbs->mbrbs_defkey;
2692 	unsigned int tmo;
2693 	size_t i, j;
2694 
2695 	if (v_flag)
2696 		return 0;
2697 
2698 	/*
2699 	 * Check default key is sane
2700 	 * - this is the most likely field to be stuffed
2701 	 * 16 disks and 16 bootable partitions seems enough!
2702 	 * (the keymap decode starts falling apart at that point)
2703 	 */
2704 	if (mbs->mbrbs_flags & MBR_BS_ASCII) {
2705 		if (key != 0 && !(key == '\r'
2706 		    || (key >= '1' && key < '1' + MAX_BIOS_DISKS)
2707 		    || (key >= 'a' && key < 'a' + MAX_BIOS_DISKS)))
2708 			return 1;
2709 	} else {
2710 		if (key != 0 && !(key == SCAN_ENTER
2711 		    || (key >= SCAN_1 && key < SCAN_1 + MAX_BIOS_DISKS)
2712 		    || (key >= SCAN_F1 && key < SCAN_F1 + MAX_BIOS_DISKS)))
2713 			return 1;
2714 	}
2715 
2716 	/* Checking the flags will lead to breakage... */
2717 
2718 	/* Timeout value is expected to be a multiple of a second */
2719 	tmo = htole16(mbs->mbrbs_timeo);
2720 	if (tmo != 0 && tmo != 0xffff && tmo != (10 * tmo + 9) / 182 * 182 / 10)
2721 		return 2;
2722 
2723 	/* Check the menu strings are printable */
2724 	/* Unfortunately they aren't zero filled... */
2725 	for (j = 0; j < __arraycount(mbs->mbrbs_nametab); ++j)
2726 	for (i = 0; i < sizeof(mbs->mbrbs_nametab[j]); i++) {
2727 		int c = (uint8_t)mbs->mbrbs_nametab[j][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 !HAVE_NBTOOL_CONFIG_H
2817 	if (wfd == fd && F_flag == 0 && ioctl(wfd, DIOCWLABEL, &flag) < 0)
2818 		warn("DIOCWLABEL");
2819 #endif
2820 	if (write_disk(0, &mboot) == -1) {
2821 		warn("Can't write fdisk partition table");
2822 		goto protect_label;
2823 	}
2824 	if (boot_installed)
2825 		for (i = bootsize; (i -= 0x200) > 0;)
2826 			if (write_disk(i / 0x200, &bootcode[i / 0x200]) == -1) {
2827 				warn("Can't write bootcode");
2828 				goto protect_label;
2829 			}
2830 	for (offset = 0, i = 0; i < ext.num_ptn; i++) {
2831 		if (write_disk(ext.base + offset, ext.ptn + i) == -1) {
2832 			warn("Can't write %dth extended partition", i);
2833 			goto protect_label;
2834 		}
2835 		offset = le32toh(ext.ptn[i].mbr_parts[1].mbrp_start);
2836 	}
2837 	rval = 0;
2838     protect_label:
2839 	flag = 0;
2840 #if !HAVE_NBTOOL_CONFIG_H
2841 	if (wfd == fd && F_flag == 0 && ioctl(wfd, DIOCWLABEL, &flag) < 0)
2842 		warn("DIOCWLABEL");
2843 #endif
2844 	return rval;
2845 }
2846 
2847 static int
2848 yesno(const char *str, ...)
2849 {
2850 	int ch, first;
2851 	va_list ap;
2852 
2853 	va_start(ap, str);
2854 	vprintf(str, ap);
2855 	va_end(ap);
2856 	printf(" [n] ");
2857 
2858 	first = ch = getchar();
2859 	while (ch != '\n' && ch != EOF)
2860 		ch = getchar();
2861 	if (ch == EOF)
2862 		errx(1, "EOF");
2863 	return (first == 'y' || first == 'Y');
2864 }
2865 
2866 static int64_t
2867 decimal(const char *prompt, int64_t dflt, int flags, int64_t minval, int64_t maxval)
2868 {
2869 	int64_t acc = 0;
2870 	int valid;
2871 	int len;
2872 	char *cp;
2873 
2874 	for (;;) {
2875 		if (flags & DEC_SEC) {
2876 			printf("%s: [%" PRId64 "..%" PRId64 "cyl default: %" PRId64 ", %" PRId64 "cyl, %uMB] ",
2877 			    prompt, SEC_TO_CYL(minval), SEC_TO_CYL(maxval),
2878 			    dflt, SEC_TO_CYL(dflt), SEC_TO_MB(dflt));
2879 		} else
2880 			printf("%s: [%" PRId64 "..%" PRId64 " default: %" PRId64 "] ",
2881 			    prompt, minval, maxval, dflt);
2882 
2883 		if (!fgets(lbuf, LBUF, stdin))
2884 			errx(1, "EOF");
2885 		cp = lbuf;
2886 
2887 		cp += strspn(cp, " \t");
2888 		if (*cp == '\n')
2889 			return dflt;
2890 
2891 		if (cp[0] == '$' && cp[1] == '\n')
2892 			return maxval;
2893 
2894 		if (isdigit((unsigned char)*cp) || *cp == '-') {
2895 			acc = strtoll(lbuf, &cp, 10);
2896 			len = strcspn(cp, " \t\n");
2897 			valid = 0;
2898 			if (len != 0 && (flags & DEC_SEC)) {
2899 				if (!strncasecmp(cp, "gb", len)) {
2900 					acc *= 1024;
2901 					valid = 1;
2902 				}
2903 				if (valid || !strncasecmp(cp, "mb", len)) {
2904 					acc *= SEC_IN_1M;
2905 					/* round to whole number of cylinders */
2906 					acc += ptn_alignment / 2;
2907 					acc /= ptn_alignment;
2908 					valid = 1;
2909 				}
2910 				if (valid || !strncasecmp(cp, "cyl", len)) {
2911 					acc *= ptn_alignment;
2912 					/* adjustments for cylinder boundary */
2913 					if (acc == 0 && flags & DEC_RND_0)
2914 						acc += ptn_0_offset;
2915 					if (flags & DEC_RND)
2916 						acc += ptn_0_offset;
2917 					if (flags & DEC_RND_DOWN)
2918 						acc -= ptn_0_offset;
2919 					if (flags & DEC_RND_DOWN_2)
2920 						acc -= ptn_0_offset;
2921 					cp += len;
2922 				}
2923 			}
2924 		}
2925 
2926 		cp += strspn(cp, " \t");
2927 		if (*cp != '\n') {
2928 			lbuf[strlen(lbuf) - 1] = 0;
2929 			printf("%s is not a valid %s number.\n", lbuf,
2930 			    flags & DEC_SEC ? "sector" : "decimal");
2931 			continue;
2932 		}
2933 
2934 		if (acc >= minval && acc <= maxval)
2935 			return acc;
2936 		printf("%" PRId64 " is not between %" PRId64 " and %" PRId64 ".\n", acc, minval, maxval);
2937 	}
2938 }
2939 
2940 static int
2941 ptn_id(const char *prompt, int *extended)
2942 {
2943 	unsigned int acc = 0;
2944 	char *cp;
2945 
2946 	for (;; printf("%s is not a valid partition number.\n", lbuf)) {
2947 		printf("%s: [none] ", prompt);
2948 
2949 		if (!fgets(lbuf, LBUF, stdin))
2950 			errx(1, "EOF");
2951 		lbuf[strlen(lbuf)-1] = '\0';
2952 		cp = lbuf;
2953 
2954 		cp += strspn(cp, " \t");
2955 		*extended = 0;
2956 		if (*cp == 0)
2957 			return -1;
2958 
2959 		if (*cp == 'E' || *cp == 'e') {
2960 			cp++;
2961 			*extended = 1;
2962 		}
2963 
2964 		acc = strtoul(cp, &cp, 10);
2965 
2966 		cp += strspn(cp, " \t");
2967 		if (*cp != '\0')
2968 			continue;
2969 
2970 		if (*extended || acc < MBR_PART_COUNT)
2971 			return acc;
2972 	}
2973 }
2974 
2975 #ifdef BOOTSEL
2976 static void
2977 string(const char *prompt, int length, char *buf)
2978 {
2979 	int len;
2980 
2981 	for (;;) {
2982 		printf("%s: [%.*s] (space to clear)", prompt, length, buf);
2983 
2984 		if (!fgets(lbuf, LBUF, stdin))
2985 			errx(1, "EOF");
2986 		len = strlen(lbuf);
2987 		if (len <= 1)
2988 			/* unchanged if just <enter> */
2989 			return;
2990 		/* now strip trailing spaces, <space><enter> deletes string */
2991 		do
2992 			lbuf[--len] = 0;
2993 		while (len != 0 && lbuf[len - 1] == ' ');
2994 		if (len < length)
2995 			break;
2996 		printf("'%s' is longer than %d characters.\n",
2997 		    lbuf, length - 1);
2998 	}
2999 	strncpy(buf, lbuf, length);
3000 }
3001 #endif
3002 
3003 static int
3004 type_match(const void *key, const void *item)
3005 {
3006 	const int *idp = key;
3007 	const struct mbr_ptype *ptr = item;
3008 
3009 	if (*idp < ptr->id)
3010 		return (-1);
3011 	if (*idp > ptr->id)
3012 		return (1);
3013 	return (0);
3014 }
3015 
3016 static const char *
3017 get_type(int type)
3018 {
3019 	struct mbr_ptype *ptr;
3020 
3021 	ptr = bsearch(&type, mbr_ptypes, KNOWN_SYSIDS,
3022 	    sizeof(mbr_ptypes[0]), type_match);
3023 	if (ptr == 0)
3024 		return ("unknown");
3025 	return (ptr->name);
3026 }
3027 
3028 static int
3029 read_gpt(daddr_t offset, struct gpt_hdr *gptp)
3030 {
3031 	char buf[512];
3032 	struct gpt_hdr *hdr = (void *)buf;
3033 	const char *tabletype = GPT_TYPE(offset);
3034 
3035 	if (read_disk(offset, buf) == -1) {
3036 		warn("Can't read %s GPT header", tabletype);
3037 		return -1;
3038 	}
3039 	(void)memcpy(gptp, buf, GPT_HDR_SIZE);
3040 
3041 	/* GPT CRC should be calculated with CRC field preset to zero */
3042 	hdr->hdr_crc_self = 0;
3043 
3044 	if (memcmp(gptp->hdr_sig, GPT_HDR_SIG, sizeof(gptp->hdr_sig))
3045 	    || gptp->hdr_lba_self != (uint64_t)offset
3046 	    || crc32(0, (void *)hdr, gptp->hdr_size) != gptp->hdr_crc_self) {
3047 		/* not a GPT */
3048 		(void)memset(gptp, 0, GPT_HDR_SIZE);
3049 	}
3050 
3051 	if (v_flag && gptp->hdr_size != 0) {
3052 		printf("Found %s GPT header CRC %"PRIu32" "
3053 		    "at sector %"PRIdaddr", backup at %"PRIdaddr"\n",
3054 		    tabletype, gptp->hdr_crc_self, offset, gptp->hdr_lba_alt);
3055 	}
3056 	return gptp->hdr_size;
3057 
3058 }
3059 
3060 static int
3061 delete_gpt(struct gpt_hdr *gptp)
3062 {
3063 	char buf[512];
3064 	struct gpt_hdr *hdr = (void *)buf;
3065 
3066 	if (g_flag)
3067 		return 0;	/* preserve existing GPT headers */
3068 
3069 	if (gptp->hdr_size == 0)
3070 		return 0;
3071 
3072 	/* don't accidently overwrite something important */
3073 	if (gptp->hdr_lba_self != GPT_HDR_BLKNO &&
3074 	    gptp->hdr_lba_self != (uint64_t)disksectors - 1) {
3075 		warnx("given GPT header location doesn't seem correct");
3076 		return -1;
3077 	}
3078 
3079 	(void)memcpy(buf, gptp, GPT_HDR_SIZE);
3080 	/*
3081 	 * Don't really delete GPT, just "disable" it, so it can
3082 	 * be recovered later in case of mistake or something
3083 	 */
3084 	(void)memset(hdr->hdr_sig, 0, sizeof(gptp->hdr_sig));
3085 	if (write_disk(gptp->hdr_lba_self, hdr) == -1) {
3086 		warn("can't delete %s GPT header",
3087 		    GPT_TYPE(gptp->hdr_lba_self));
3088 		return -1;
3089 	}
3090 	(void)memset(gptp, 0, GPT_HDR_SIZE);
3091 	return 1;
3092 }
3093