xref: /netbsd-src/sbin/fdisk/fdisk.c (revision 5c707f942d3e0e883d1de259017bf5870b34bb9d)
1 /*	$NetBSD: fdisk.c,v 1.162 2025/01/03 16:16:14 rillig 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 1.162 2025/01/03 16:16:14 rillig 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 static 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 
210 static int a_flag;		/* set active partition */
211 static int i_flag;		/* init bootcode */
212 static int I_flag;		/* ignore errors */
213 static int u_flag;		/* update partition data */
214 static int v_flag;		/* more verbose */
215 static int sh_flag;		/* Output data as shell defines */
216 static int f_flag;		/* force --not interactive */
217 static int g_flag;		/* preserve GPT headers */
218 static int s_flag;		/* set id,offset,size */
219 static int b_flag;		/* Set cyl, heads, secs (as c/h/s) */
220 static int B_flag;		/* Edit/install bootselect code */
221 static int E_flag;		/* extended partition number */
222 static int b_cyl, b_head, b_sec;  /* b_flag values. */
223 
224 #if !HAVE_NBTOOL_CONFIG_H
225 static int F_flag = 0;
226 #else
227 /* Tool - force 'file' mode to avoid unsupported functions and ioctls */
228 static int F_flag = 1;
229 #endif
230 
231 static struct gpt_hdr gpt1, gpt2;	/* GUID partition tables */
232 
233 static struct mbr_sector bootcode[8192 / sizeof (struct mbr_sector)];
234 static ssize_t secsize = 512;	/* sector size */
235 static char *iobuf;		/* buffer for non 512 sector I/O */
236 static int bootsize;		/* actual size of bootcode */
237 static int boot_installed;	/* 1 if we've copied code into the mbr */
238 
239 #if defined(USE_DISKLIST)
240 #include <machine/cpu.h>
241 static struct disklist *dl;
242 #endif
243 
244 
245 #define KNOWN_SYSIDS	(sizeof(mbr_ptypes)/sizeof(mbr_ptypes[0]))
246 
247 __dead static void	usage(void);
248 static void	print_s0(int);
249 static void	print_part(struct mbr_sector *, int, daddr_t);
250 static void	print_mbr_partition(struct mbr_sector *, int, daddr_t, daddr_t, int);
251 static void	print_pbr(daddr_t, int, uint8_t);
252 static int	is_all_zero(const unsigned char *, size_t);
253 static void	printvis(int, const char *, const char *, size_t);
254 static int	read_boot(const char *, void *, size_t, int);
255 static void	init_sector0(int);
256 static void	intuit_translated_geometry(void);
257 static void	get_bios_geometry(void);
258 static void	get_extended_ptn(void);
259 static void	get_ptn_alignmemt(void);
260 #if defined(USE_DISKLIST)
261 static void	get_diskname(const char *, char *, size_t);
262 #endif
263 static int	change_part(int, int, int, daddr_t, daddr_t, char *);
264 static void	print_geometry(void);
265 static int	first_active(void);
266 static void	change_active(int);
267 static void	change_bios_geometry(void);
268 static void	dos(int, unsigned char *, unsigned char *, unsigned char *);
269 static int	open_disk(int);
270 static ssize_t	read_disk(daddr_t, void *);
271 static ssize_t	write_disk(daddr_t, void *);
272 static int	get_params(void);
273 static int	read_s0(daddr_t, struct mbr_sector *);
274 static int	write_mbr(void);
275 static int	read_gpt(daddr_t, struct gpt_hdr *);
276 static int	delete_gpt(struct gpt_hdr *);
277 static int	yesno(const char *, ...) __printflike(1, 2);
278 static int64_t	decimal(const char *, int64_t, int, int64_t, int64_t);
279 #define DEC_SEC		1		/* asking for a sector number */
280 #define	DEC_RND		2		/* round to end of first track */
281 #define	DEC_RND_0	4		/* convert 0 to size of a track */
282 #define DEC_RND_DOWN	8		/* subtract 1 track */
283 #define DEC_RND_DOWN_2	16		/* subtract 2 tracks */
284 static int	ptn_id(const char *, int *);
285 static int	type_match(const void *, const void *);
286 static const char *get_type(int);
287 static int	get_mapping(int, unsigned int *, unsigned int *, unsigned int *, unsigned long *);
288 #ifdef BOOTSEL
289 static daddr_t	configure_bootsel(daddr_t);
290 static void	install_bootsel(int);
291 static daddr_t	get_default_boot(void);
292 static void	set_default_boot(daddr_t);
293 static void	string(const char *, int, char *);
294 #endif
295 
296 static void
297 initvar_disk(const char **diskp)
298 {
299 #if !HAVE_NBTOOL_CONFIG_H
300 	int mib[2];
301 	size_t len;
302 	char *root_device;
303 
304 	mib[0] = CTL_KERN;
305 	mib[1] = KERN_ROOT_DEVICE;
306 	if (sysctl(mib, 2, NULL, &len, NULL, 0) == -1 ||
307 	    (root_device = malloc(len)) == NULL ||
308 	    sysctl(mib, 2, root_device, &len, NULL, 0) == -1)
309 		return;
310 
311 	*diskp = root_device;
312 #endif /* HAVE_NBTOOL_CONFIG_H */
313 }
314 
315 static int
316 getnum(const char *str, int *num)
317 {
318 	char *e;
319 	long l;
320 
321 	errno = 0;
322 	l = strtol(str, &e, 0);
323 	if (str[0] == '\0' || *e != '\0')
324 		return -1;
325 	if (errno == ERANGE && (l == LONG_MAX || l == LONG_MIN))
326 		return -1;
327 	/* XXX: truncation */
328 	*num = (int)l;
329 	return 0;
330 }
331 
332 /* [<sysid>][/[<start>][/[<size>][/[<bootmenu>]]]] */
333 static int
334 parse_s(char *arg, int *csysid, unsigned *cstart, unsigned *csize,
335     char **cbootmenu)
336 {
337 	char *ptr;
338 	int num;
339 
340 	if ((ptr = strchr(arg, '/')) != NULL)
341 		*ptr++ = '\0';
342 
343 	if (*arg) {
344 		if (getnum(arg, &num) == -1)
345 			return -1;
346 		*csysid = num;
347 	}
348 	if (ptr == NULL)
349 		return 0;
350 
351 	arg = ptr;
352 	if ((ptr = strchr(arg, '/')) != NULL)
353 		*ptr++ = '\0';
354 	if (*arg) {
355 		if (getnum(arg, &num) == -1)
356 			return -1;
357 		*cstart = num;
358 	}
359 	if (ptr == NULL)
360 		return 0;
361 
362 	arg = ptr;
363 	if ((ptr = strchr(arg, '/')) != NULL)
364 		*ptr++ = '\0';
365 	if (*arg) {
366 		if (getnum(arg, &num) == -1)
367 			return -1;
368 		*csize = num;
369 	}
370 	if (ptr != NULL && *ptr)
371 		*cbootmenu = ptr;
372 	return 0;
373 }
374 
375 int
376 main(int argc, char *argv[])
377 {
378 	struct stat sb;
379 	int ch;
380 	size_t len;
381 	char *cp;
382 	int n;
383 #ifdef BOOTSEL
384 	daddr_t default_ptn;		/* start sector of default ptn */
385 #endif
386 	char *cbootmenu = 0;
387 
388 	int csysid;	/* For the s_flag. */
389 	unsigned int cstart, csize;
390 	a_flag = u_flag = sh_flag = f_flag = s_flag = b_flag = 0;
391 	i_flag = B_flag = 0;
392 	v_flag = 0;
393 	E_flag = 0;
394 	csysid = -1;
395 	cstart = csize = ~0U;
396 	while ((ch = getopt(argc, argv, OPTIONS)) != -1) {
397 		switch (ch) {
398 		case '0':
399 			partition = 0;
400 			break;
401 		case '1':
402 			partition = 1;
403 			break;
404 		case '2':
405 			partition = 2;
406 			break;
407 		case '3':
408 			partition = 3;
409 			break;
410 		case 'E':	/* Extended partition number */
411 			E_flag = 1;
412 			unsigned long ul = strtoul(optarg, &cp, 0);
413 			if (*cp || ul > INT_MAX)
414 				errx(1, "Bad partition number -E %s.", optarg);
415 			partition = (int)ul;
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 'z':
496 			secsize = atoi(optarg);
497 			if (secsize <= 512 || (secsize & (secsize - 1)) != 0)
498 				errx(EXIT_FAILURE, "Invalid sector size %zd",
499 				    secsize);
500 			break;
501 		default:
502 			usage();
503 		}
504 	}
505 	argc -= optind;
506 	argv += optind;
507 
508 	if (sh_flag && (a_flag || i_flag || u_flag || f_flag || s_flag))
509 		usage();
510 
511 	if (B_flag && f_flag) {
512 		warnx("Bootselector may only be configured interactively");
513 		usage();
514 	}
515 
516 	if (f_flag && u_flag && !s_flag) {
517 		warnx("Partition data not specified");
518 		usage();
519 	}
520 
521 	if (s_flag && partition == -1) {
522 		warnx("-s flag requires a partition selected.");
523 		usage();
524 	}
525 
526 	if (argc > 1)
527 		usage();
528 
529 	if (argc > 0)
530 		disk = argv[0];
531 	else if (!F_flag) {
532 		/* Default to boot device */
533 		initvar_disk(&disk);
534 	}
535 
536 	if (!F_flag && stat(disk, &sb) == 0 && S_ISREG(sb.st_mode))
537 		F_flag = 1;
538 
539 	if (open_disk(B_flag || a_flag || i_flag || u_flag) < 0)
540 		exit(1);
541 
542 	if (secsize > 512) {
543 		if ((iobuf = malloc(secsize)) == NULL)
544 			err(EXIT_FAILURE, "Cannot allocate %zd buffer",
545 			    secsize);
546 	}
547 
548 	if (read_s0(0, &mboot))
549 		/* must have been a blank disk */
550 		init_sector0(1);
551 
552 	read_gpt(GPT_HDR_BLKNO, &gpt1);
553 	read_gpt(disksectors - 1, &gpt2);
554 
555 	if (b_flag) {
556 		dos_cylinders = b_cyl;
557 		dos_heads = b_head;
558 		dos_sectors = b_sec;
559 	} else {
560 		get_bios_geometry();
561 	}
562 
563 	if (ptn_alignment == 0)
564 		get_ptn_alignmemt();
565 
566 	get_extended_ptn();
567 
568 #ifdef BOOTSEL
569 	default_ptn = get_default_boot();
570 #endif
571 
572 	if (E_flag && !u_flag && partition >= ext.num_ptn)
573 		errx(1, "Extended partition %d is not defined.", partition);
574 
575 	/* Do the update stuff! */
576 	if (u_flag) {
577 		if (!f_flag && !b_flag)
578 			change_bios_geometry();
579 
580 		if (s_flag)
581 			change_part(E_flag, partition, csysid, cstart, csize,
582 				cbootmenu);
583 		else {
584 			int part = partition, chg_ext = E_flag, prompt = 1;
585 			do {
586 				if (prompt) {
587 					printf("\n");
588 					print_s0(partition);
589 				}
590 				if (partition == -1)
591 					part = ptn_id(
592 				    "Which partition do you want to change?",
593 							&chg_ext);
594 				if (part < 0)
595 					break;
596 				prompt = change_part(chg_ext, part, 0, 0, 0, 0);
597 			} while (partition == -1);
598 		}
599 	} else {
600 		if (!i_flag && !B_flag) {
601 			print_geometry();
602 			print_s0(partition);
603 		}
604 	}
605 
606 	if (a_flag && !E_flag)
607 		change_active(partition);
608 
609 #ifdef BOOTSEL
610 	if (B_flag || u_flag || i_flag)
611 		/* Ensure the mbr code supports this configuration */
612 		install_bootsel(0);
613 	if (B_flag)
614 		default_ptn = configure_bootsel(default_ptn);
615 	set_default_boot(default_ptn);
616 #else
617 	if (i_flag)
618 		init_sector0(0);
619 #endif
620 
621 	if (u_flag || a_flag || i_flag || B_flag) {
622 		if (!f_flag) {
623 			printf("\nWe haven't written the MBR back to disk "
624 			       "yet.  This is your last chance.\n");
625 			if (u_flag)
626 				print_s0(-1);
627 			if (gpt1.hdr_size != 0 || gpt2.hdr_size != 0)
628 				printf("\nWARNING: The disk is carrying "
629 				       "GUID Partition Tables.\n"
630 				       "         If you continue, "
631 				       "GPT headers will be deleted.\n\n");
632 			if (yesno("Should we write new partition table?")) {
633 				delete_gpt(&gpt1);
634 				delete_gpt(&gpt2);
635 				write_mbr();
636 			}
637 		} else {
638 			if (delete_gpt(&gpt1) > 0)
639 				warnx("Primary GPT header was deleted");
640 			if (delete_gpt(&gpt2) > 0)
641 				warnx("Secondary GPT header was deleted");
642 			write_mbr();
643 		}
644 	}
645 
646 	exit(0);
647 }
648 
649 static void
650 usage(void)
651 {
652 	int indent = 7 + (int)strlen(getprogname()) + 1;
653 
654 	(void)fprintf(stderr, "usage: %s [-aBFfgIilSuv] "
655 		"[-A ptn_alignment[/ptn_0_offset]] \\\n"
656 		"%*s[-b cylinders/heads/sectors] \\\n"
657 		"%*s[-0123 | -E num "
658 		"[-s [id][/[start][/[size][/bootmenu]]]] \\\n"
659 		"%*s[-t disktab] [-T disktype] \\\n"
660 		"%*s[-c bootcode] "
661 		"[-r|-w file] [-z sectorsize] [device]\n"
662 		"\t-a change active partition\n"
663 		"\t-f force - not interactive\n"
664 		"\t-g preserve existing GPT headers\n"
665 		"\t-i initialise MBR code\n"
666 		"\t-I ignore errors about no space or overlapping partitions\n"
667 		"\t-l list partition types\n"
668 		"\t-u update partition data\n"
669 		"\t-v verbose output, -v -v more verbose still\n"
670 		"\t-B update bootselect options\n"
671 		"\t-F treat device as a regular file\n"
672 		"\t-S output as shell defines\n"
673 		"\t-r and -w access 'file' for non-destructive testing\n",
674 		getprogname(), indent, "", indent, "", indent, "", indent, "");
675 	exit(1);
676 }
677 
678 static daddr_t
679 ext_offset(int part)
680 {
681 	daddr_t offset = ext.base;
682 
683 	if (part != 0)
684 		offset += le32toh(ext.ptn[part - 1].mbr_parts[1].mbrp_start);
685 	return offset;
686 }
687 
688 static void
689 print_s0(int which)
690 {
691 	int part;
692 
693 	if (which == -1) {
694 		if (!sh_flag)
695 			printf("Partition table:\n");
696 		for (part = 0; part < MBR_PART_COUNT; part++) {
697 			if (!sh_flag)
698 				printf("%d: ", part);
699 			print_part(&mboot, part, 0);
700 		}
701 		if (!sh_flag) {
702 			if (ext.is_corrupt)
703 				printf("Extended partition table is corrupt\n");
704 			else
705 				if (ext.num_ptn != 0)
706 					printf("Extended partition table:\n");
707 		}
708 		for (part = 0; part < ext.num_ptn; part++) {
709 			if (!sh_flag)
710 				printf("E%d: ", part);
711 			print_part(&ext.ptn[part], 0, ext_offset(part));
712 			if (!sh_flag && v_flag >= 2) {
713 				printf("link: ");
714 				print_mbr_partition(&ext.ptn[part], 1,
715 						ext_offset(part), ext.base, 0);
716 			}
717 		}
718 #ifdef BOOTSEL
719 		if (!sh_flag && mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
720 			int tmo;
721 
722 			printf("Bootselector ");
723 			if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ACTIVE) {
724 				printf("enabled");
725 				tmo = le16toh(mboot.mbr_bootsel.mbrbs_timeo);
726 				if (tmo == 0xffff)
727 					printf(", infinite timeout");
728 				else
729 					printf(", timeout %d seconds",
730 						    (10 * tmo + 9) / 182);
731 			} else
732 				printf("disabled");
733 			printf(".\n");
734 		}
735 #endif
736 		if (!sh_flag) {
737 			int active = first_active();
738 			if (active == MBR_PART_COUNT)
739 				printf("No active partition.\n");
740 			else
741 				printf("First active partition: %d\n", active);
742 		}
743 		if (!sh_flag)
744 			printf("Drive serial number: %"PRIu32" (0x%08x)\n",
745 			    le32toh(mboot.mbr_dsn),
746 			    le32toh(mboot.mbr_dsn));
747 		return;
748 	}
749 
750 	if (E_flag) {
751 		if (!sh_flag)
752 			printf("Extended partition E%d:\n", which);
753 		if (which > ext.num_ptn)
754 			printf("Undefined\n");
755 		else
756 			print_part(&ext.ptn[which], 0, ext_offset(which));
757 	} else {
758 		if (!sh_flag)
759 			printf("Partition %d:\n", which);
760 		print_part(&mboot, which, 0);
761 	}
762 }
763 
764 static void
765 print_part(struct mbr_sector *boot, int part, daddr_t offset)
766 {
767 	struct mbr_partition *partp;
768 	const char *e;
769 
770 	if (!sh_flag) {
771 		print_mbr_partition(boot, part, offset, 0, 0);
772 		return;
773 	}
774 
775 	partp = &boot->mbr_parts[part];
776 	if (boot != &mboot) {
777 		part = boot - ext.ptn;
778 		e = "E";
779 	} else
780 		e = "";
781 
782 	if (partp->mbrp_type == 0) {
783 		printf("PART%s%dSIZE=0\n", e, part);
784 		return;
785 	}
786 
787 	printf("PART%s%dID=%d\n", e, part, partp->mbrp_type);
788 	printf("PART%s%dSIZE=%u\n", e, part, le32toh(partp->mbrp_size));
789 	printf("PART%s%dSTART=%"PRIdaddr"\n", e, part,
790 	    offset + le32toh(partp->mbrp_start));
791 	printf("PART%s%dFLAG=0x%x\n", e, part, partp->mbrp_flag);
792 	printf("PART%s%dBCYL=%d\n", e, part,
793 	    MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect));
794 	printf("PART%s%dBHEAD=%d\n", e, part, partp->mbrp_shd);
795 	printf("PART%s%dBSEC=%d\n", e, part, MBR_PSECT(partp->mbrp_ssect));
796 	printf("PART%s%dECYL=%d\n", e, part,
797 	    MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect));
798 	printf("PART%s%dEHEAD=%d\n", e, part, partp->mbrp_ehd);
799 	printf("PART%s%dESEC=%d\n", e, part, MBR_PSECT(partp->mbrp_esect));
800 }
801 
802 static void
803 pr_cyls(daddr_t sector, int is_end)
804 {
805 	unsigned long cyl, head, sect;
806 	cyl = sector / dos_cylindersectors;
807 	sect = sector - cyl * dos_cylindersectors;
808 	head = sect / dos_sectors;
809 	sect -= head * dos_sectors;
810 
811 	printf("%lu", cyl);
812 
813 	if (is_end) {
814 		if (head == dos_heads - 1 && sect == dos_sectors - 1)
815 			return;
816 	} else {
817 		if (head == 0 && sect == 0)
818 			return;
819 	}
820 
821 	printf("/%lu/%lu", head, sect + 1);
822 }
823 
824 static void
825 print_mbr_partition(struct mbr_sector *boot, int part,
826     daddr_t offset, daddr_t exoffset, int indent)
827 {
828 	daddr_t	start;
829 	daddr_t	size;
830 	struct mbr_partition *partp = &boot->mbr_parts[part];
831 	struct mbr_sector eboot;
832 	int p;
833 	static int dumped = 0;
834 
835 	if (partp->mbrp_type == 0 && v_flag < 2) {
836 		printf("<UNUSED>\n");
837 		return;
838 	}
839 
840 	start = le32toh(partp->mbrp_start);
841 	size = le32toh(partp->mbrp_size);
842 	if (MBR_IS_EXTENDED(partp->mbrp_type))
843 		start += exoffset;
844 	else
845 		start += offset;
846 
847 	printf("%s (sysid %d)\n", get_type(partp->mbrp_type), partp->mbrp_type);
848 #ifdef BOOTSEL
849 	if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC &&
850 	    boot->mbr_bootsel.mbrbs_nametab[part][0])
851 		printf("%*s    bootmenu: %s\n", indent, "",
852 		    boot->mbr_bootsel.mbrbs_nametab[part]);
853 #endif
854 
855 	printf("%*s    start %"PRIdaddr", size %"PRIdaddr,
856 	    indent, "", start, size);
857 	if (size != 0) {
858 		printf(" (%u MB, Cyls ", SEC_TO_MB(size));
859 		if (v_flag == 0 && le32toh(partp->mbrp_start) == ptn_0_offset)
860 			pr_cyls(start - ptn_0_offset, 0);
861 		else
862 			pr_cyls(start, 0);
863 		printf("-");
864 		pr_cyls(start + size - 1, 1);
865 		printf(")");
866 	}
867 
868 	switch (partp->mbrp_flag) {
869 	case 0:
870 		break;
871 	case MBR_PFLAG_ACTIVE:
872 		printf(", Active");
873 		break;
874 	default:
875 		printf(", flag 0x%x", partp->mbrp_flag);
876 		break;
877 	}
878 	printf("\n");
879 
880 	if (v_flag) {
881 		printf("%*s        beg: cylinder %4d, head %3d, sector %2d\n",
882 		    indent, "",
883 		    MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect),
884 		    partp->mbrp_shd, MBR_PSECT(partp->mbrp_ssect));
885 		printf("%*s        end: cylinder %4d, head %3d, sector %2d\n",
886 		    indent, "",
887 		    MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect),
888 		    partp->mbrp_ehd, MBR_PSECT(partp->mbrp_esect));
889 	}
890 
891 	if (partp->mbrp_type == 0 && start == 0 && v_flag < 3)
892 		return;
893 
894 	if (! MBR_IS_EXTENDED(partp->mbrp_type))
895 		print_pbr(start, indent + 8, partp->mbrp_type);
896 
897 	if (!MBR_IS_EXTENDED(partp->mbrp_type) ||
898 	    (v_flag <= 2 && !ext.is_corrupt))
899 		return;
900 
901 	/*
902 	 * Recursive dump extended table,
903 	 * This is read from the disk - so is wrong during editing.
904 	 * Just ensure we only show it once.
905 	 */
906 	if (dumped)
907 		return;
908 
909 	printf("%*s    Extended partition table:\n", indent, "");
910 	indent += 4;
911 	if (read_s0(start, &eboot) == -1)
912 		return;
913 	for (p = 0; p < MBR_PART_COUNT; p++) {
914 		printf("%*s%d: ", indent, "", p);
915 		print_mbr_partition(&eboot, p, start,
916 				    exoffset ? exoffset : start, indent);
917 	}
918 
919 	if (exoffset == 0)
920 		dumped = 1;
921 }
922 
923 /* Print a line with a label and a vis-encoded string */
924 static void
925 printvis(int indent, const char *label, const char *buf, size_t size)
926 {
927 	char *visbuf;
928 
929 	if ((visbuf = malloc(size * 4 + 1)) == NULL)
930 		err(1, "Malloc failed");
931 	strsvisx(visbuf, buf, size, VIS_TAB|VIS_NL|VIS_OCTAL, "\"");
932 	printf("%*s%s: \"%s\"\n",
933 	    indent, "",
934 	    label, visbuf);
935 	free(visbuf);
936 }
937 
938 /* Check whether a buffer contains all bytes zero */
939 static int
940 is_all_zero(const unsigned char *p, size_t size)
941 {
942 
943 	while (size-- > 0) {
944 		if (*p++ != 0)
945 			return 0;
946 	}
947 	return 1;
948 }
949 
950 /*
951  * Report on the contents of a PBR sector.
952  *
953  * We first perform several sanity checks.  If vflag >= 2, we report all
954  * failing tests, but for smaller values of v_flag we stop after the
955  * first failing test.  Tests are ordered in an attempt to get the most
956  * useful error message from the first failing test.
957  *
958  * If v_flag >= 2, we also report some decoded values from the PBR.
959  * These results may be meaningless, if the PBR doesn't follow common
960  * conventions.
961  *
962  * Trying to decode anything more than the magic number in the last
963  * two bytes is a layering violation, but it can be very useful in
964  * diagnosing boot failures.
965  */
966 static void
967 print_pbr(daddr_t sector, int indent, uint8_t part_type __unused)
968 {
969 	struct mbr_sector pboot;
970 	unsigned char *p, *endp;
971 	unsigned char val;
972 	int ok;
973 	int errcount = 0;
974 
975 #define PBR_ERROR(...)							\
976 	do {								\
977 		++errcount;						\
978 		printf("%*s%s: ", indent, "",				\
979 		    (v_flag < 2 ? "PBR is not bootable" : "Not bootable")); \
980 		printf(__VA_ARGS__);					\
981 		if (v_flag < 2)						\
982 			return;						\
983 	} while (/*CONSTCOND*/ 0)
984 
985 	if (v_flag >= 2) {
986 		printf("%*sInformation from PBR:\n",
987 		    indent, "");
988 		indent += 4;
989 	}
990 
991 	if (read_disk(sector, &pboot) == -1) {
992 		PBR_ERROR("Sector %"PRIdaddr" is unreadable (%s)\n",
993 		    sector, strerror(errno));
994 		return;
995 	}
996 
997 	/* all bytes identical? */
998 	p = (unsigned char *)&pboot;
999 	endp = p + sizeof(pboot);
1000 	val = *p;
1001 	ok = 0;
1002 	for (; p < endp; p++) {
1003 		if (*p != val) {
1004 			ok = 1;
1005 			break;
1006 		}
1007 	}
1008 	if (! ok)
1009 		PBR_ERROR("All bytes are identical (0x%02x)\n", val);
1010 
1011 	if (pboot.mbr_magic != LE_MBR_MAGIC)
1012 		PBR_ERROR("Bad magic number (0x%04x)\n",
1013 			le16toh(pboot.mbr_magic));
1014 
1015 #if 0
1016 	/* Some i386 OS might fail this test.  All non-i386 will fail. */
1017 	if (pboot.mbr_jmpboot[0] != 0xE9
1018 	    && pboot.mbr_jmpboot[0] != 0xEB) {
1019 		PBR_ERROR("Does not begin with i386 JMP instruction"
1020 			" (0x%02x 0x%02x0 0x%02x)\n",
1021 		    pboot.mbr_jmpboot[0], pboot.mbr_jmpboot[1],
1022 		    pboot.mbr_jmpboot[2]);
1023 	}
1024 #endif
1025 
1026 	if (v_flag > 0 && errcount == 0)
1027 		printf("%*sPBR appears to be bootable\n",
1028 		    indent, "");
1029 	if (v_flag < 2)
1030 		return;
1031 
1032 	if (! is_all_zero(pboot.mbr_oemname, sizeof(pboot.mbr_oemname))) {
1033 		printvis(indent, "OEM name", (char *)pboot.mbr_oemname,
1034 			sizeof(pboot.mbr_oemname));
1035 	}
1036 
1037 	if (pboot.mbr_bpb.bpb16.bsBootSig == 0x29)
1038 		printf("%*sBPB FAT16 boot signature found\n",
1039 		    indent, "");
1040 	if (pboot.mbr_bpb.bpb32.bsBootSig == 0x29)
1041 		printf("%*sBPB FAT32 boot signature found\n",
1042 		    indent, "");
1043 
1044 #undef PBR_ERROR
1045 }
1046 
1047 static int
1048 read_boot(const char *name, void *buf, size_t len, int err_exit)
1049 {
1050 	int bfd, ret;
1051 	struct stat st;
1052 
1053 	if (boot_path != NULL)
1054 		free(boot_path);
1055 	if (strchr(name, '/') == 0)
1056 		asprintf(&boot_path, "%s/%s", boot_dir, name);
1057 	else
1058 		boot_path = strdup(name);
1059 	if (boot_path == NULL)
1060 		err(1, "Malloc failed");
1061 
1062 	if ((bfd = open(boot_path, O_RDONLY)) < 0 || fstat(bfd, &st) == -1) {
1063 		warn("%s", boot_path);
1064 		goto fail;
1065 	}
1066 
1067 	if (st.st_size > (off_t)len) {
1068 		warnx("%s: bootcode too large", boot_path);
1069 		goto fail;
1070 	}
1071 	ret = st.st_size;
1072 	if (ret < 0x200) {
1073 		warnx("%s: bootcode too small", boot_path);
1074 		goto fail;
1075 	}
1076 	if (read(bfd, buf, len) != ret) {
1077 		warn("%s", boot_path);
1078 		goto fail;
1079 	}
1080 
1081 	if (((struct mbr_sector *)buf)->mbr_magic != LE_MBR_MAGIC) {
1082 		warnx("%s: invalid magic", boot_path);
1083 		goto fail;
1084 	}
1085 
1086 	close(bfd);
1087 	ret = (ret + 0x1ff) & ~0x1ff;
1088 	return ret;
1089 
1090     fail:
1091 	if (bfd >= 0)
1092 		close(bfd);
1093 	if (err_exit)
1094 		exit(1);
1095 	return 0;
1096 }
1097 
1098 static void
1099 init_sector0(int zappart)
1100 {
1101 	int i;
1102 	int copy_size = offsetof(struct mbr_sector, mbr_dsn);
1103 
1104 #ifdef DEFAULT_BOOTCODE
1105 	if (bootsize == 0)
1106 		bootsize = read_boot(DEFAULT_BOOTCODE, bootcode,
1107 			sizeof bootcode, 0);
1108 #endif
1109 #ifdef BOOTSEL
1110 	if (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC
1111 	    && bootcode[0].mbr_bootsel_magic == LE_MBR_BS_MAGIC)
1112 		copy_size = MBR_BS_OFFSET;
1113 #endif
1114 
1115 	if (bootsize != 0) {
1116 		boot_installed = 1;
1117 		memcpy(&mboot, bootcode, copy_size);
1118 		mboot.mbr_bootsel_magic = bootcode[0].mbr_bootsel_magic;
1119 	}
1120 	mboot.mbr_magic = LE_MBR_MAGIC;
1121 
1122 	if (!zappart)
1123 		return;
1124 	for (i = 0; i < MBR_PART_COUNT; i++)
1125 		memset(&mboot.mbr_parts[i], 0, sizeof(mboot.mbr_parts[i]));
1126 }
1127 
1128 static void
1129 get_extended_ptn(void)
1130 {
1131 	struct mbr_partition *mp;
1132 	struct mbr_sector *boot;
1133 	daddr_t offset;
1134 
1135 	/* find first (there should only be one) extended partition */
1136 	for (mp = mboot.mbr_parts; !MBR_IS_EXTENDED(mp->mbrp_type); mp++)
1137 		if (mp >= &mboot.mbr_parts[MBR_PART_COUNT])
1138 			return;
1139 
1140 	/*
1141 	 * The extended partition should be structured as a linked list
1142 	 * (even though it appears, at first glance, to be a tree).
1143 	 */
1144 	ext.base = le32toh(mp->mbrp_start);
1145 	ext.limit = ext.base + le32toh(mp->mbrp_size);
1146 	ext.ptn_id = mp - mboot.mbr_parts;
1147 	for (offset = 0;; offset = le32toh(boot->mbr_parts[1].mbrp_start)) {
1148 		if (reallocarr(&ext.ptn,
1149 		    ext.num_ptn + 1, sizeof(*ext.ptn)) != 0)
1150 			err(1, "Malloc failed");
1151 		boot = ext.ptn + ext.num_ptn;
1152 		if (read_s0(offset + ext.base, boot) == -1)
1153 			break;
1154 		/* expect p0 to be valid and p1 to be another extended ptn */
1155 		if (MBR_IS_EXTENDED(boot->mbr_parts[0].mbrp_type))
1156 			break;
1157 		if (boot->mbr_parts[1].mbrp_type != 0 &&
1158 		    !MBR_IS_EXTENDED(boot->mbr_parts[1].mbrp_type))
1159 			break;
1160 		/* p2 and p3 should be unallocated */
1161 		if (boot->mbr_parts[2].mbrp_type != 0 ||
1162 		    boot->mbr_parts[3].mbrp_type != 0)
1163 			break;
1164 		/* data ptn inside extended one */
1165 		if (boot->mbr_parts[0].mbrp_type != 0 &&
1166 		    offset + le32toh(boot->mbr_parts[0].mbrp_start)
1167 		    + le32toh(boot->mbr_parts[0].mbrp_size) > ext.limit)
1168 			break;
1169 
1170 		ext.num_ptn++;
1171 
1172 		if (boot->mbr_parts[1].mbrp_type == 0)
1173 			/* end of extended partition chain */
1174 			return;
1175 		/* must be in sector order */
1176 		if (offset >= le32toh(boot->mbr_parts[1].mbrp_start))
1177 			break;
1178 	}
1179 
1180 	warnx("Extended partition table is corrupt");
1181 	ext.is_corrupt = 1;
1182 	ext.num_ptn = 0;
1183 }
1184 
1185 #if defined(USE_DISKLIST)
1186 static void
1187 get_diskname(const char *fullname, char *diskname, size_t size)
1188 {
1189 	const char *p, *p2;
1190 	size_t len;
1191 
1192 	p = strrchr(fullname, '/');
1193 	if (p == NULL)
1194 		p = fullname;
1195 	else
1196 		p++;
1197 
1198 	if (*p == 0) {
1199 		strlcpy(diskname, fullname, size);
1200 		return;
1201 	}
1202 
1203 	if (*p == 'r')
1204 		p++;
1205 
1206 	for (p2 = p; *p2 != 0; p2++)
1207 		if (isdigit((unsigned char)*p2))
1208 			break;
1209 	if (*p2 == 0) {
1210 		/* XXX invalid diskname? */
1211 		strlcpy(diskname, fullname, size);
1212 		return;
1213 	}
1214 	while (isdigit((unsigned char)*p2))
1215 		p2++;
1216 
1217 	len = p2 - p;
1218 	if (len > size) {
1219 		/* XXX */
1220 		strlcpy(diskname, fullname, size);
1221 		return;
1222 	}
1223 
1224 	memcpy(diskname, p, len);
1225 	diskname[len] = 0;
1226 }
1227 #endif
1228 
1229 static void
1230 get_ptn_alignmemt(void)
1231 {
1232 	struct mbr_partition *partp = &mboot.mbr_parts[0];
1233 	uint32_t ptn_0_base, ptn_0_limit;
1234 
1235 	/* Default to using 'traditional' cylinder alignment */
1236 	ptn_alignment = dos_cylindersectors;
1237 	ptn_0_offset = dos_sectors;
1238 
1239 	if (partp->mbrp_type != 0) {
1240 		/* Try to copy alignment of first partition */
1241 		ptn_0_base = le32toh(partp->mbrp_start);
1242 		ptn_0_limit = ptn_0_base + le32toh(partp->mbrp_size);
1243 		if (!(ptn_0_limit & 2047)) {
1244 			/* Partition ends on a 1MB boundary, align to 1MB */
1245 			ptn_alignment = 2048;
1246 			if (ptn_0_base <= 2048
1247 			    && !(ptn_0_base & (ptn_0_base - 1))) {
1248 				/* ptn_base is a power of 2, use it */
1249 				ptn_0_offset = ptn_0_base;
1250 			}
1251 		}
1252 	} else {
1253 		/* Use 1MB alignment for large disks */
1254 		if (disksectors > 2048 * 1024 * 128) {
1255 			ptn_alignment = 2048;
1256 			ptn_0_offset = 2048;
1257 		}
1258 	}
1259 }
1260 
1261 static void
1262 get_bios_geometry(void)
1263 {
1264 #if defined(USE_DISKLIST)
1265 	int mib[2], i;
1266 	size_t len;
1267 	struct biosdisk_info *bip;
1268 	struct nativedisk_info *nip;
1269 	char diskname[8];
1270 
1271 	mib[0] = CTL_MACHDEP;
1272 	mib[1] = CPU_DISKINFO;
1273 	if (sysctl(mib, 2, NULL, &len, NULL, 0) < 0) {
1274 		goto out;
1275 	}
1276 	dl = (struct disklist *) malloc(len);
1277 	if (dl == NULL)
1278 		err(1, "Malloc failed");
1279 	if (sysctl(mib, 2, dl, &len, NULL, 0) < 0) {
1280 		free(dl);
1281 		dl = 0;
1282 		goto out;
1283 	}
1284 
1285 	get_diskname(disk, diskname, sizeof diskname);
1286 
1287 	for (i = 0; i < dl->dl_nnativedisks; i++) {
1288 		nip = &dl->dl_nativedisks[i];
1289 		if (strcmp(diskname, nip->ni_devname))
1290 			continue;
1291 		/*
1292 		 * XXX listing possible matches is better. This is ok for
1293 		 * now because the user has a chance to change it later.
1294 		 * Also, if all the disks have the same parameters then we can
1295 		 * just use them, we don't need to know which disk is which.
1296 		 */
1297 		if (nip->ni_nmatches != 0) {
1298 			bip = &dl->dl_biosdisks[nip->ni_biosmatches[0]];
1299 			dos_cylinders = bip->bi_cyl;
1300 			dos_heads = bip->bi_head;
1301 			dos_sectors = bip->bi_sec;
1302 			if (bip->bi_lbasecs)
1303 				dos_disksectors = bip->bi_lbasecs;
1304 			return;
1305 		}
1306 	}
1307  out:
1308 #endif
1309 	/* Allright, allright, make a stupid guess.. */
1310 	intuit_translated_geometry();
1311 }
1312 
1313 #ifdef BOOTSEL
1314 static daddr_t
1315 get_default_boot(void)
1316 {
1317 	unsigned int id;
1318 	int p;
1319 
1320 	if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1321 		/* default to first active partition */
1322 		return DEFAULT_ACTIVE;
1323 
1324 	id = mboot.mbr_bootsel.mbrbs_defkey;
1325 
1326 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ASCII) {
1327 		/* Keycode is ascii */
1328 		if (id == '\r')
1329 		    return DEFAULT_ACTIVE;
1330 		/* '1'+ => allocated partition id, 'a'+ => disk 0+ */
1331 		if (id >= 'a' && id < 'a' + MAX_BIOS_DISKS)
1332 			return DEFAULT_DISK(id - 'a');
1333 		id -= '1';
1334 	} else {
1335 		/* keycode is PS/2 keycode */
1336 		if (id == SCAN_ENTER)
1337 			return DEFAULT_ACTIVE;
1338 		/* 1+ => allocated partition id, F1+ => disk 0+ */
1339 		if (id >= SCAN_F1 && id < SCAN_F1 + MAX_BIOS_DISKS)
1340 			return DEFAULT_DISK(id - SCAN_F1);
1341 		id -= SCAN_1;
1342 	}
1343 
1344 	/* Convert partition index to the invariant start sector number */
1345 
1346 	for (p = 0; p < MBR_PART_COUNT; p++) {
1347 		if (mboot.mbr_parts[p].mbrp_type == 0)
1348 			continue;
1349 		if (mboot.mbr_bootsel.mbrbs_nametab[p][0] == 0)
1350 			continue;
1351 		if (id-- == 0)
1352 			return le32toh(mboot.mbr_parts[p].mbrp_start);
1353 	}
1354 
1355 	for (p = 0; p < ext.num_ptn; p++) {
1356 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1357 			continue;
1358 		if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1359 			continue;
1360 		if (id-- == 0)
1361 			return ext_offset(p)
1362 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start);
1363 	}
1364 
1365 	return DEFAULT_ACTIVE;
1366 }
1367 
1368 static void
1369 set_default_boot(daddr_t default_ptn)
1370 {
1371 	int p;
1372 	static const unsigned char key_list[] = { SCAN_ENTER, SCAN_F1, SCAN_1,
1373 						'\r', 'a', '1' };
1374 	const unsigned char *key = key_list;
1375 
1376 	if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1377 		/* sanity */
1378 		return;
1379 
1380 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_ASCII)
1381 		/* Use ascii values */
1382 		key += 3;
1383 
1384 	if (default_ptn == DEFAULT_ACTIVE) {
1385 		mboot.mbr_bootsel.mbrbs_defkey = key[0];
1386 		return;
1387 	}
1388 
1389 	if (default_ptn >= DEFAULT_DISK(0)
1390 	    && default_ptn < DEFAULT_DISK(MAX_BIOS_DISKS)) {
1391 		mboot.mbr_bootsel.mbrbs_defkey = key[1]
1392 		    + default_ptn - DEFAULT_DISK(0);
1393 		return;
1394 	}
1395 
1396 	mboot.mbr_bootsel.mbrbs_defkey = key[2];
1397 	for (p = 0; p < MBR_PART_COUNT; p++) {
1398 		if (mboot.mbr_parts[p].mbrp_type == 0)
1399 			continue;
1400 		if (mboot.mbr_bootsel.mbrbs_nametab[p][0] == 0)
1401 			continue;
1402 		if (le32toh(mboot.mbr_parts[p].mbrp_start) == default_ptn)
1403 			return;
1404 		mboot.mbr_bootsel.mbrbs_defkey++;
1405 	}
1406 
1407 	if (mboot.mbr_bootsel.mbrbs_flags & MBR_BS_EXTLBA) {
1408 		for (p = 0; p < ext.num_ptn; p++) {
1409 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1410 				continue;
1411 			if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1412 				continue;
1413 			if (le32toh(ext.ptn[p].mbr_parts[0].mbrp_start) +
1414 			    ext_offset(p) == default_ptn)
1415 				return;
1416 			mboot.mbr_bootsel.mbrbs_defkey++;
1417 		}
1418 	}
1419 
1420 	/* Default to first active partition */
1421 	mboot.mbr_bootsel.mbrbs_defkey = key[0];
1422 }
1423 
1424 static void
1425 install_bootsel(int needed)
1426 {
1427 	struct mbr_bootsel *mbs = &mboot.mbr_bootsel;
1428 	int p;
1429 	int ext13 = 0;
1430 	const char *code;
1431 
1432 	needed |= MBR_BS_NEWMBR;	/* need new bootsel code */
1433 
1434 	/* Work out which boot code we need for this configuration */
1435 	for (p = 0; p < MBR_PART_COUNT; p++) {
1436 		if (mboot.mbr_parts[p].mbrp_type == 0)
1437 			continue;
1438 		if (mboot.mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1439 			break;
1440 		if (mbs->mbrbs_nametab[p][0] == 0)
1441 			continue;
1442 		needed |= MBR_BS_ACTIVE;
1443 		if (le32toh(mboot.mbr_parts[p].mbrp_start) >= dos_totalsectors)
1444 			ext13 = MBR_BS_EXTINT13;
1445 	}
1446 
1447 	for (p = 0; p < ext.num_ptn; p++) {
1448 		if (ext.ptn[p].mbr_bootsel_magic != LE_MBR_BS_MAGIC)
1449 			continue;
1450 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1451 			continue;
1452 		if (ext.ptn[p].mbr_bootsel.mbrbs_nametab[p][0] == 0)
1453 			continue;
1454 		needed |= MBR_BS_EXTLBA | MBR_BS_ACTIVE;
1455 	}
1456 
1457 	if (B_flag)
1458 		needed |= MBR_BS_ACTIVE;
1459 
1460 	/* Is the installed code good enough ? */
1461 	if (!i_flag && (needed == 0 ||
1462 	    (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC
1463 	    && (mbs->mbrbs_flags & needed) == needed))) {
1464 		/* yes - just set flags */
1465 		mbs->mbrbs_flags |= ext13;
1466 		return;
1467 	}
1468 
1469 	/* ok - we need to replace the bootcode */
1470 
1471 	if (f_flag && !(i_flag || B_flag)) {
1472 		warnx("Installed bootfile doesn't support required options.");
1473 		return;
1474 	}
1475 
1476 	if (!f_flag && bootsize == 0 && !i_flag)
1477 		/* Output an explanation for the 'update bootcode' prompt. */
1478 		printf("\n%s\n",
1479 		    "Installed bootfile doesn't support required options.");
1480 
1481 	/* Were we told a specific file ? (which we have already read) */
1482 	/* If so check that it supports what we need. */
1483 	if (bootsize != 0 && needed != 0
1484 	    && (bootcode[0].mbr_bootsel_magic != LE_MBR_BS_MAGIC
1485 	    || ((bootcode[0].mbr_bootsel.mbrbs_flags & needed) != needed))) {
1486 		/* No it doesn't... */
1487 		if (f_flag)
1488 			warnx("Bootfile %s doesn't support "
1489 				    "required bootsel options", boot_path );
1490 			/* But install it anyway */
1491 		else
1492 			if (yesno("Bootfile %s doesn't support the required "
1493 			    "options,\ninstall default bootfile instead?",
1494 			    boot_path))
1495 				bootsize = 0;
1496 	}
1497 
1498 	if (bootsize == 0) {
1499 		/* Get name of bootfile that supports the required facilities */
1500 		code = DEFAULT_BOOTCODE;
1501 		if (needed & MBR_BS_ACTIVE)
1502 			code = DEFAULT_BOOTSELCODE;
1503 #ifdef DEFAULT_BOOTEXTCODE
1504 		if (needed & MBR_BS_EXTLBA)
1505 			code = DEFAULT_BOOTEXTCODE;
1506 #endif
1507 
1508 		bootsize = read_boot(code, bootcode, sizeof bootcode, 0);
1509 		if (bootsize == 0)
1510 			/* The old bootcode is better than no bootcode at all */
1511 			return;
1512 		if ((bootcode[0].mbr_bootsel.mbrbs_flags & needed) != needed)
1513 			warnx("Default bootfile %s doesn't support required "
1514 				"options.  Got flags 0x%x, wanted 0x%x\n",
1515 				boot_path, bootcode[0].mbr_bootsel.mbrbs_flags,
1516 				needed);
1517 	}
1518 
1519 	if (!f_flag && !yesno("Update the bootcode from %s?", boot_path))
1520 		return;
1521 
1522 	init_sector0(0);
1523 
1524 	if (mboot.mbr_bootsel_magic == LE_MBR_BS_MAGIC)
1525 		mbs->mbrbs_flags = bootcode[0].mbr_bootsel.mbrbs_flags | ext13;
1526 }
1527 
1528 static daddr_t
1529 configure_bootsel(daddr_t default_ptn)
1530 {
1531 	struct mbr_bootsel *mbs = &mboot.mbr_bootsel;
1532 	int i, item, opt;
1533 	int tmo;
1534 	daddr_t *off;
1535 	int num_bios_disks;
1536 
1537 #if defined(USE_DISKLIST)
1538 	if (dl != NULL) {
1539 		num_bios_disks = dl->dl_nbiosdisks;
1540 		if (num_bios_disks > MAX_BIOS_DISKS)
1541 			num_bios_disks = MAX_BIOS_DISKS;
1542 	} else
1543 #endif
1544 		num_bios_disks = MAX_BIOS_DISKS;
1545 
1546 	printf("\nBoot selector configuration:\n");
1547 
1548 	/* The timeout value is in ticks, ~18.2 Hz. Avoid using floats.
1549 	 * Ticks are nearly 64k/3600 - so our long timers are sligtly out!
1550 	 * Newer bootcode always waits for 1 tick, so treats 0xffff
1551 	 * as wait forever.
1552 	 */
1553 	tmo = le16toh(mbs->mbrbs_timeo);
1554 	tmo = tmo == 0xffff ? -1 : (10 * tmo + 9) / 182;
1555 	tmo = decimal("Timeout value (0 to 3600 seconds, -1 => never)",
1556 			tmo, 0, -1, 3600);
1557 	mbs->mbrbs_timeo = htole16(tmo == -1 ? 0xffff : (tmo * 182) / 10);
1558 
1559 	off = calloc(1 + MBR_PART_COUNT + ext.num_ptn + num_bios_disks, sizeof *off);
1560 	if (off == NULL)
1561 		err(1, "Malloc failed");
1562 
1563 	printf("Select the default boot option. Options are:\n\n");
1564 	item = 0;
1565 	opt = 0;
1566 	off[opt] = DEFAULT_ACTIVE;
1567 	printf("%d: The first active partition\n", opt);
1568 	for (i = 0; i < MBR_PART_COUNT; i++) {
1569 		if (mboot.mbr_parts[i].mbrp_type == 0)
1570 			continue;
1571 		if (mbs->mbrbs_nametab[i][0] == 0)
1572 			continue;
1573 		printf("%d: %s\n", ++opt, &mbs->mbrbs_nametab[i][0]);
1574 		off[opt] = le32toh(mboot.mbr_parts[i].mbrp_start);
1575 		if (off[opt] == default_ptn)
1576 			item = opt;
1577 	}
1578 	if (mbs->mbrbs_flags & MBR_BS_EXTLBA) {
1579 		for (i = 0; i < ext.num_ptn; i++) {
1580 			if (ext.ptn[i].mbr_parts[0].mbrp_type == 0)
1581 				continue;
1582 			if (ext.ptn[i].mbr_bootsel.mbrbs_nametab[0][0] == 0)
1583 				continue;
1584 			printf("%d: %s\n",
1585 			    ++opt, ext.ptn[i].mbr_bootsel.mbrbs_nametab[0]);
1586 			off[opt] = ext_offset(i) +
1587 			    le32toh(ext.ptn[i].mbr_parts[0].mbrp_start);
1588 			if (off[opt] == default_ptn)
1589 				item = opt;
1590 		}
1591 	}
1592 	for (i = 0; i < num_bios_disks; i++) {
1593 		printf("%d: Harddisk %d\n", ++opt, i);
1594 		off[opt] = DEFAULT_DISK(i);
1595 		if (DEFAULT_DISK(i) == default_ptn)
1596 			item = opt;
1597 	}
1598 
1599 	item = decimal("Default boot option", item, 0, 0, opt);
1600 
1601 	default_ptn = off[item];
1602 	free(off);
1603 	return default_ptn;
1604 }
1605 #endif /* BOOTSEL */
1606 
1607 
1608 /* Prerequisite: the disklabel parameters and master boot record must
1609  *		 have been read (i.e. dos_* and mboot are meaningful).
1610  * Specification: modifies dos_cylinders, dos_heads, dos_sectors, and
1611  *		  dos_cylindersectors to be consistent with what the
1612  *		  partition table is using, if we can find a geometry
1613  *		  which is consistent with all partition table entries.
1614  *		  We may get the number of cylinders slightly wrong (in
1615  *		  the conservative direction).  The idea is to be able
1616  *		  to create a NetBSD partition on a disk we don't know
1617  *		  the translated geometry of.
1618  * This routine is only used for non-x86 systems or when we fail to
1619  * get the BIOS geometry from the kernel.
1620  */
1621 static void
1622 intuit_translated_geometry(void)
1623 {
1624 	uint32_t xcylinders;
1625 	int xheads = -1, xsectors = -1, i, j;
1626 	unsigned int c1, h1, s1, c2, h2, s2;
1627 	unsigned long a1, a2;
1628 	uint64_t num, denom;
1629 
1630 	/*
1631 	 * The physical parameters may be invalid as bios geometry.
1632 	 * If we cannot determine the actual bios geometry, we are
1633 	 * better off picking a likely 'faked' geometry than leaving
1634 	 * the invalid physical one.
1635 	 */
1636 
1637 	if (dos_cylinders > MAXCYL || dos_heads > MAXHEAD ||
1638 	    dos_sectors > MAXSECTOR) {
1639 		h1 = MAXHEAD - 1;
1640 		c1 = MAXCYL - 1;
1641 #if defined(USE_DISKLIST)
1642 		if (dl != NULL) {
1643 			/* BIOS may use 256 heads or 1024 cylinders */
1644 			for (i = 0; i < dl->dl_nbiosdisks; i++) {
1645 				if (h1 < (unsigned int)dl->dl_biosdisks[i].bi_head)
1646 					h1 = dl->dl_biosdisks[i].bi_head;
1647 				if (c1 < (unsigned int)dl->dl_biosdisks[i].bi_cyl)
1648 					c1 = dl->dl_biosdisks[i].bi_cyl;
1649 			}
1650 		}
1651 #endif
1652 		dos_sectors = MAXSECTOR;
1653 		dos_heads = h1;
1654 		dos_cylinders = disklabel.d_secperunit / (MAXSECTOR * h1);
1655 		if (dos_cylinders > c1)
1656 			dos_cylinders = c1;
1657 	}
1658 
1659 	/* Try to deduce the number of heads from two different mappings. */
1660 	for (i = 0; i < MBR_PART_COUNT * 2 - 1; i++) {
1661 		if (get_mapping(i, &c1, &h1, &s1, &a1) < 0)
1662 			continue;
1663 		a1 -= s1;
1664 		for (j = i + 1; j < MBR_PART_COUNT * 2; j++) {
1665 			if (get_mapping(j, &c2, &h2, &s2, &a2) < 0)
1666 				continue;
1667 			a2 -= s2;
1668 			num = (uint64_t)h1 * a2 - (uint64_t)h2 * a1;
1669 			denom = (uint64_t)c2 * a1 - (uint64_t)c1 * a2;
1670 			if (denom != 0 && num != 0 && num % denom == 0) {
1671 				xheads = num / denom;
1672 				xsectors = a1 / (c1 * xheads + h1);
1673 				break;
1674 			}
1675 		}
1676 		if (xheads != -1)
1677 			break;
1678 	}
1679 
1680 	if (xheads == -1) {
1681 		if (F_flag)
1682 			return;
1683 		warnx("Cannot determine the number of heads");
1684 		return;
1685 	}
1686 
1687 	if (xsectors == -1) {
1688 		warnx("Cannot determine the number of sectors");
1689 		return;
1690 	}
1691 
1692 	/* Estimate the number of cylinders. */
1693 	xcylinders = disklabel.d_secperunit / xheads / xsectors;
1694 	if (disklabel.d_secperunit > xcylinders * xheads * xsectors)
1695 		xcylinders++;
1696 
1697 	/*
1698 	 * Now verify consistency with each of the partition table entries.
1699 	 * Be willing to shove cylinders up a little bit to make things work,
1700 	 * but translation mismatches are fatal.
1701 	 */
1702 	for (i = 0; i < MBR_PART_COUNT * 2; i++) {
1703 		if (get_mapping(i, &c1, &h1, &s1, &a1) < 0)
1704 			continue;
1705 		if (c1 >= MAXCYL - 2)
1706 			continue;
1707 		if (xsectors * (c1 * xheads + h1) + s1 != a1)
1708 			return;
1709 	}
1710 
1711 
1712 	/* Everything checks out.
1713 	 * Reset the geometry to use for further calculations.
1714 	 * But cylinders cannot be > 1024.
1715 	 */
1716 	if (xcylinders > MAXCYL)
1717 		dos_cylinders = MAXCYL;
1718 	else
1719 		dos_cylinders = xcylinders;
1720 	dos_heads = xheads;
1721 	dos_sectors = xsectors;
1722 }
1723 
1724 /*
1725  * For the purposes of intuit_translated_geometry(), treat the partition
1726  * table as a list of eight mapping between (cylinder, head, sector)
1727  * triplets and absolute sectors.  Get the relevant geometry triplet and
1728  * absolute sectors for a given entry, or return -1 if it isn't present.
1729  * Note: for simplicity, the returned sector is 0-based.
1730  */
1731 static int
1732 get_mapping(int i, unsigned int *cylinder, unsigned int *head, unsigned int *sector,
1733     unsigned long *absolute)
1734 {
1735 	struct mbr_partition *part = &mboot.mbr_parts[i / 2];
1736 
1737 	if (part->mbrp_type == 0)
1738 		return -1;
1739 	if (i % 2 == 0) {
1740 		*cylinder = MBR_PCYL(part->mbrp_scyl, part->mbrp_ssect);
1741 		*head = part->mbrp_shd;
1742 		*sector = MBR_PSECT(part->mbrp_ssect);
1743 		*absolute = le32toh(part->mbrp_start);
1744 	} else {
1745 		*cylinder = MBR_PCYL(part->mbrp_ecyl, part->mbrp_esect);
1746 		*head = part->mbrp_ehd;
1747 		*sector = MBR_PSECT(part->mbrp_esect);
1748 		*absolute = le32toh(part->mbrp_start)
1749 		    + le32toh(part->mbrp_size) - 1;
1750 	}
1751 	/* Sanity check the data against all zeroes */
1752 	if ((*cylinder == 0) && (*sector == 0) && (*head == 0))
1753 		return -1;
1754 	/* sector numbers in the MBR partition table start at 1 */
1755 	*sector = *sector - 1;
1756 	/* Sanity check the data against max values */
1757 	if ((((*cylinder * MAXHEAD) + *head) * MAXSECTOR + *sector) < *absolute)
1758 		/* cannot be a CHS mapping */
1759 		return -1;
1760 	return 0;
1761 }
1762 
1763 static void
1764 delete_ptn(int part)
1765 {
1766 	if (part == ext.ptn_id) {
1767 		/* forget all about the extended partition */
1768 		free(ext.ptn);
1769 		memset(&ext, 0, sizeof ext);
1770 	}
1771 
1772 	mboot.mbr_parts[part].mbrp_type = 0;
1773 }
1774 
1775 static void
1776 delete_ext_ptn(int part)
1777 {
1778 
1779 	if (part == 0) {
1780 		ext.ptn[0].mbr_parts[0].mbrp_type = 0;
1781 		return;
1782 	}
1783 	ext.ptn[part - 1].mbr_parts[1] = ext.ptn[part].mbr_parts[1];
1784 	memmove(&ext.ptn[part], &ext.ptn[part + 1],
1785 		(ext.num_ptn - part - 1) * sizeof ext.ptn[0]);
1786 	ext.num_ptn--;
1787 }
1788 
1789 static int
1790 add_ext_ptn(daddr_t start, daddr_t size)
1791 {
1792 	int part;
1793 	struct mbr_partition *partp;
1794 
1795 	if (reallocarr(&ext.ptn, ext.num_ptn + 1, sizeof(*ext.ptn)) != 0)
1796 		err(1, "reallocarr");
1797 	for (part = 0; part < ext.num_ptn; part++)
1798 		if (ext_offset(part) > start)
1799 			break;
1800 	/* insert before 'part' - make space... */
1801 	memmove(&ext.ptn[part + 1], &ext.ptn[part],
1802 		(ext.num_ptn - part) * sizeof ext.ptn[0]);
1803 	memset(&ext.ptn[part], 0, sizeof ext.ptn[0]);
1804 	ext.ptn[part].mbr_magic = LE_MBR_MAGIC;
1805 	/* we will be 'part' */
1806 	if (part == 0) {
1807 		/* link us to 'next' */
1808 		partp = &ext.ptn[0].mbr_parts[1];
1809 		/* offset will be fixed by caller */
1810 		partp->mbrp_size = htole32(
1811 		    le32toh(ext.ptn[1].mbr_parts[0].mbrp_start) +
1812 		    le32toh(ext.ptn[1].mbr_parts[0].mbrp_size));
1813 	} else {
1814 		/* link us to prev's next */
1815 		partp = &ext.ptn[part - 1].mbr_parts[1];
1816 		ext.ptn[part].mbr_parts[1] = *partp;
1817 		/* and prev onto us */
1818 		partp->mbrp_start = htole32(start - ptn_0_offset - ext.base);
1819 		partp->mbrp_size = htole32(size + ptn_0_offset);
1820 	}
1821 	partp->mbrp_type = 5;	/* as used by win98 */
1822 	partp->mbrp_flag = 0;
1823 	/* wallop in some CHS values - win98 doesn't saturate them */
1824 	dos(le32toh(partp->mbrp_start),
1825 	    &partp->mbrp_scyl, &partp->mbrp_shd, &partp->mbrp_ssect);
1826 	dos(le32toh(partp->mbrp_start) + le32toh(partp->mbrp_size) - 1,
1827 	    &partp->mbrp_ecyl, &partp->mbrp_ehd, &partp->mbrp_esect);
1828 	ext.num_ptn++;
1829 
1830 	return part;
1831 }
1832 
1833 static const char *
1834 check_overlap(int part, int sysid, daddr_t start, daddr_t size, int fix)
1835 {
1836 	int p;
1837 	unsigned int p_s, p_e;
1838 
1839 	if (sysid != 0) {
1840 		if (start == 0)
1841 			return "Sector zero is reserved for the MBR";
1842 #if 0
1843 		if (start < ptn_0_offset)
1844 			/* This is just a convention, not a requirement */
1845 			return "Track zero is reserved for the BIOS";
1846 #endif
1847 		if (start + size > disksectors)
1848 			return "Partition exceeds size of disk";
1849 		for (p = 0; p < MBR_PART_COUNT; p++) {
1850 			if (p == part || mboot.mbr_parts[p].mbrp_type == 0)
1851 				continue;
1852 			p_s = le32toh(mboot.mbr_parts[p].mbrp_start);
1853 			p_e = p_s + le32toh(mboot.mbr_parts[p].mbrp_size);
1854 			if (start + size <= p_s || start >= p_e)
1855 				continue;
1856 			if (f_flag) {
1857 				if (fix)
1858 					delete_ptn(p);
1859 				return 0;
1860 			}
1861 			return "Overlaps another partition";
1862 		}
1863 	}
1864 
1865 	/* Are we trying to create an extended partition */
1866 	if (!MBR_IS_EXTENDED(mboot.mbr_parts[part].mbrp_type)) {
1867 		/* this wasn't the extended partition */
1868 		if (!MBR_IS_EXTENDED(sysid))
1869 			return 0;
1870 		/* making an extended partition */
1871 		if (ext.base != 0) {
1872 			if (!f_flag)
1873 				return "There cannot be 2 extended partitions";
1874 			if (fix)
1875 				delete_ptn(ext.ptn_id);
1876 		}
1877 		if (fix) {
1878 			/* allocate a new extended partition */
1879 			ext.ptn = calloc(1, sizeof ext.ptn[0]);
1880 			if (ext.ptn == NULL)
1881 				err(1, "Malloc failed");
1882 			ext.ptn[0].mbr_magic = LE_MBR_MAGIC;
1883 			ext.ptn_id = part;
1884 			ext.base = start;
1885 			ext.limit = start + size;
1886 			ext.num_ptn = 1;
1887 		}
1888 		return 0;
1889 	}
1890 
1891 	/* Check we haven't cut space allocated to an extended ptn */
1892 
1893 	if (!MBR_IS_EXTENDED(sysid)) {
1894 		/* no longer an extended partition */
1895 		if (fix) {
1896 			/* Kill all memory of the extended partitions */
1897 			delete_ptn(part);
1898 			return 0;
1899 		}
1900 		if (ext.num_ptn == 0 ||
1901 		    (ext.num_ptn == 1 && ext.ptn[0].mbr_parts[0].mbrp_type == 0))
1902 			/* nothing in extended partition */
1903 			return 0;
1904 		if (f_flag)
1905 			return 0;
1906 		if (yesno("Do you really want to delete all the extended partitions?"))
1907 			return 0;
1908 		return "Extended partition busy";
1909 	}
1910 
1911 	if (le32toh(mboot.mbr_parts[part].mbrp_start) != ext.base)
1912 		/* maybe impossible, but an extra sanity check */
1913 		return 0;
1914 
1915 	for (p = ext.num_ptn; --p >= 0;) {
1916 		if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1917 			continue;
1918 		p_s = ext_offset(p);
1919 		p_e = p_s + le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
1920 			  + le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
1921 		if (p_s >= start && p_e <= start + size)
1922 			continue;
1923 		if (!f_flag)
1924 			return "Extended partition outside main partition";
1925 		if (fix)
1926 			delete_ext_ptn(p);
1927 	}
1928 
1929 	if (fix && start != ext.base) {
1930 		/* The internal offsets need to be fixed up */
1931 		for (p = 0; p < ext.num_ptn - 1; p++)
1932 			ext.ptn[p].mbr_parts[1].mbrp_start = htole32(
1933 			    le32toh(ext.ptn[p].mbr_parts[1].mbrp_start)
1934 				    + ext.base - start);
1935 		/* and maybe an empty partition at the start */
1936 		if (ext.ptn[0].mbr_parts[0].mbrp_type == 0) {
1937 			if (le32toh(ext.ptn[0].mbr_parts[1].mbrp_start) == 0) {
1938 				/* don't need the empty slot */
1939 				memmove(&ext.ptn[0], &ext.ptn[1],
1940 					(ext.num_ptn - 1) * sizeof ext.ptn[0]);
1941 				ext.num_ptn--;
1942 			}
1943 		} else {
1944 			/* must create an empty slot */
1945 			add_ext_ptn(start, ptn_0_offset);
1946 			ext.ptn[0].mbr_parts[1].mbrp_start = htole32(ext.base
1947 								- start);
1948 		}
1949 	}
1950 	if (fix) {
1951 		ext.base = start;
1952 		ext.limit = start + size;
1953 	}
1954 	return 0;
1955 }
1956 
1957 static const char *
1958 check_ext_overlap(int part, int sysid, daddr_t start, daddr_t size, int fix)
1959 {
1960 	int p;
1961 	unsigned int p_s, p_e;
1962 
1963 	if (sysid == 0)
1964 		return 0;
1965 
1966 	if (MBR_IS_EXTENDED(sysid))
1967 		return "Nested extended partitions are not allowed";
1968 
1969 	/* allow one track at start for extended partition header */
1970 	start -= ptn_0_offset;
1971 	size += ptn_0_offset;
1972 	if (start < ext.base || start + size > ext.limit)
1973 		return "Outside bounds of extended partition";
1974 
1975 	if (f_flag && !fix)
1976 		return 0;
1977 
1978 	for (p = ext.num_ptn; --p >= 0;) {
1979 		if (p == part || ext.ptn[p].mbr_parts[0].mbrp_type == 0)
1980 			continue;
1981 		p_s = ext_offset(p);
1982 		p_e = p_s + le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
1983 			+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
1984 		if (p == 0)
1985 			p_s += le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
1986 							- ptn_0_offset;
1987 		if (start < p_e && start + size > p_s) {
1988 			if (!f_flag)
1989 				return "Overlaps another extended partition";
1990 			if (fix) {
1991 				if (part == -1)
1992 					delete_ext_ptn(p);
1993 				else
1994 					/* must not change numbering yet */
1995 					ext.ptn[p].mbr_parts[0].mbrp_type = 0;
1996 			}
1997 		}
1998 	}
1999 	return 0;
2000 }
2001 
2002 static int
2003 change_part(int extended, int part, int sysid, daddr_t start, daddr_t size,
2004 	char *bootmenu)
2005 {
2006 	struct mbr_partition *partp;
2007 	struct mbr_sector *boot;
2008 	daddr_t offset;
2009 	const char *e;
2010 	int upart = part;
2011 	int p;
2012 	int fl;
2013 	daddr_t n_s, n_e;
2014 	const char *errtext;
2015 #ifdef BOOTSEL
2016 	char tmp_bootmenu[MBR_PART_COUNT * (MBR_BS_PARTNAMESIZE + 1)];
2017 	int bootmenu_len = (extended ? MBR_PART_COUNT : 1) * (MBR_BS_PARTNAMESIZE + 1);
2018 #endif
2019 
2020 	if (extended) {
2021 		if (part != -1 && part < ext.num_ptn) {
2022 			boot = &ext.ptn[part];
2023 			partp = &boot->mbr_parts[0];
2024 			offset = ext_offset(part);
2025 		} else {
2026 			part = -1;
2027 			boot = 0;
2028 			partp = 0;
2029 			offset = 0;
2030 		}
2031 		upart = 0;
2032 		e = "E";
2033 	} else {
2034 		boot = &mboot;
2035 		partp = &boot->mbr_parts[part];
2036 		offset = 0;
2037 		e = "";
2038 	}
2039 
2040 	if (!f_flag && part != -1) {
2041 		printf("The data for partition %s%d is:\n", e, part);
2042 		print_part(boot, upart, offset);
2043 	}
2044 
2045 #ifdef BOOTSEL
2046 	if (bootmenu != NULL)
2047 		strlcpy(tmp_bootmenu, bootmenu, bootmenu_len);
2048 	else
2049 		if (boot != NULL && boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC)
2050 			strlcpy(tmp_bootmenu,
2051 				boot->mbr_bootsel.mbrbs_nametab[upart],
2052 				bootmenu_len);
2053 		else
2054 			tmp_bootmenu[0] = 0;
2055 #endif
2056 
2057 	if (partp != NULL) {
2058 		if (!s_flag) {
2059 			/* values not specified, default to current ones */
2060 			sysid = partp->mbrp_type;
2061 			start = offset + le32toh(partp->mbrp_start);
2062 			size = le32toh(partp->mbrp_size);
2063 		} else {
2064 			if (sysid == -1)
2065 				sysid = partp->mbrp_type;
2066 			if (start == (daddr_t)0xffffffff) {
2067 				start = offset + le32toh(partp->mbrp_start);
2068 				if (start == 0)
2069 					start = offset = ptn_0_offset;
2070 			}
2071 			if (size == (daddr_t)0xffffffff) {
2072 				size = le32toh(partp->mbrp_size);
2073 				if (size == 0)
2074 					size = disksectors - start;
2075 			}
2076 		}
2077 	}
2078 
2079 	/* creating a new partition, default to free space */
2080 	if (!s_flag && sysid == 0 && extended) {
2081 		/* non-extended partition */
2082 		start = ext.base;
2083 		for (p = 0; p < ext.num_ptn; p++) {
2084 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2085 				continue;
2086 			n_s = ext_offset(p);
2087 			if (n_s > start + ptn_0_offset)
2088 				break;
2089 			start = ext_offset(p)
2090 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2091 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size);
2092 		}
2093 		if (ext.limit - start <= ptn_0_offset) {
2094 			printf("No space in extended partition\n");
2095 			return 0;
2096 		}
2097 		start += ptn_0_offset;
2098 	}
2099 
2100 	if (!s_flag && sysid == 0 && !extended) {
2101 		/* same for non-extended partition */
2102 		/* first see if old start is free */
2103 		if (start < ptn_0_offset)
2104 			start = 0;
2105 		for (p = 0; start != 0 && p < MBR_PART_COUNT; p++) {
2106 			if (mboot.mbr_parts[p].mbrp_type == 0)
2107 				continue;
2108 			n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2109 			if (start >= n_s &&
2110 			    start < n_s + le32toh(mboot.mbr_parts[p].mbrp_size))
2111 				start = 0;
2112 		}
2113 		if (start == 0) {
2114 			/* Look for first gap */
2115 			start = ptn_0_offset;
2116 			for (p = 0; p < MBR_PART_COUNT; p++) {
2117 				if (mboot.mbr_parts[p].mbrp_type == 0)
2118 					continue;
2119 				n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2120 				n_e = n_s + le32toh(mboot.mbr_parts[p].mbrp_size);
2121 				if (start >= n_s && start < n_e) {
2122 					start = n_e;
2123 					p = -1;
2124 				}
2125 			}
2126 			if (start >= disksectors && !I_flag) {
2127 				printf("No free space\n");
2128 				return 0;
2129 			}
2130 		}
2131 	}
2132 
2133 	if (!f_flag) {
2134 		/* request new values from user */
2135 		if (sysid == 0)
2136 			sysid = 169;
2137 		sysid = decimal("sysid", sysid, 0, 0, 255);
2138 		if (sysid == 0 && !v_flag) {
2139 			start = 0;
2140 			size = 0;
2141 #ifdef BOOTSEL
2142 			tmp_bootmenu[0] = 0;
2143 #endif
2144 		} else {
2145 			daddr_t old = start;
2146 			daddr_t lim = extended ? ext.limit : disksectors;
2147 			start = decimal("start", start,
2148 				DEC_SEC | DEC_RND_0 | (extended ? DEC_RND : 0),
2149 				extended ? ext.base : 0, lim);
2150 			/* Adjust 'size' so that end doesn't move when 'start'
2151 			 * is only changed slightly.
2152 			 */
2153 			if (size > start - old)
2154 				size -= start - old;
2155 			else
2156 				size = 0;
2157 			/* Find end of available space from this start point */
2158 			if (extended) {
2159 				for (p = 0; p < ext.num_ptn; p++) {
2160 					if (p == part)
2161 						continue;
2162 					if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2163 						continue;
2164 					n_s = ext_offset(p);
2165 					if (n_s > start && n_s < lim)
2166 						lim = n_s;
2167 					if (start >= n_s && start < n_s
2168 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_start)
2169 				+ le32toh(ext.ptn[p].mbr_parts[0].mbrp_size)) {
2170 						lim = start;
2171 						break;
2172 					}
2173 				}
2174 			} else {
2175 				for (p = 0; p < MBR_PART_COUNT; p++) {
2176 					if (p == part)
2177 						continue;
2178 					if (mboot.mbr_parts[p].mbrp_type == 0)
2179 						continue;
2180 					n_s = le32toh(mboot.mbr_parts[p].mbrp_start);
2181 					if (n_s > start && n_s < lim)
2182 						lim = n_s;
2183 					if (start >= n_s && start < n_s
2184 				    + le32toh(mboot.mbr_parts[p].mbrp_size)) {
2185 						lim = start;
2186 						break;
2187 					}
2188 				}
2189 			}
2190 			lim -= start;
2191 			if (lim == 0) {
2192 				printf("Start sector already allocated\n");
2193 				return 0;
2194 			}
2195 			if (size == 0 || size > lim)
2196 				size = lim;
2197 			fl = DEC_SEC;
2198 			if (start % ptn_alignment == ptn_0_offset)
2199 				fl |= DEC_RND_DOWN;
2200 			if (start == 2 * ptn_0_offset)
2201 				fl |= DEC_RND_DOWN | DEC_RND_DOWN_2;
2202 			size = decimal("size", size, fl, 0, lim);
2203 #ifdef BOOTSEL
2204 #ifndef DEFAULT_BOOTEXTCODE
2205 			if (!extended)
2206 #endif
2207 				string("bootmenu", bootmenu_len, tmp_bootmenu);
2208 #endif
2209 		}
2210 	}
2211 
2212 	/*
2213 	 * Before we write these away, we must verify that nothing
2214 	 * untoward has been requested.
2215 	 */
2216 
2217 	if (extended)
2218 		errtext = check_ext_overlap(part, sysid, start, size, 0);
2219 	else
2220 		errtext = check_overlap(part, sysid, start, size, 0);
2221 	if (errtext != NULL && !I_flag) {
2222 		if (f_flag)
2223 			errx(2, "%s", errtext);
2224 		printf("%s\n", errtext);
2225 		return 0;
2226 	}
2227 
2228 	/*
2229 	 * Before proceeding, delete any overlapped partitions.
2230 	 * This can only happen if '-f' was supplied on the command line.
2231 	 * Just hope the caller knows what they are doing.
2232 	 * This also fixes the base of each extended partition if the
2233 	 * partition itself has moved.
2234 	 */
2235 	if (!I_flag) {
2236 		if (extended)
2237 			errtext = check_ext_overlap(part, sysid, start, size, 1);
2238 		else
2239 			errtext = check_overlap(part, sysid, start, size, 1);
2240 		if (errtext)
2241 			errx(1, "%s", errtext);
2242 	}
2243 
2244 
2245 	if (sysid == 0) {
2246 		/* delete this partition - save info though */
2247 		if (partp == NULL)
2248 			/* must have been trying to create an extended ptn */
2249 			return 0;
2250 		if (start == 0 && size == 0)
2251 			memset(partp, 0, sizeof *partp);
2252 #ifdef BOOTSEL
2253 		if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC)
2254 			memset(boot->mbr_bootsel.mbrbs_nametab[upart], 0,
2255 				sizeof boot->mbr_bootsel.mbrbs_nametab[0]);
2256 #endif
2257 		if (extended)
2258 			delete_ext_ptn(part);
2259 		else
2260 			delete_ptn(part);
2261 		return 1;
2262 	}
2263 
2264 
2265 	if (extended) {
2266 		if (part != -1)
2267 			delete_ext_ptn(part);
2268 		if (start == ext.base + ptn_0_offset)
2269 			/* First one must have been free */
2270 			part = 0;
2271 		else
2272 			part = add_ext_ptn(start, size);
2273 
2274 		/* These must be re-calculated because of the realloc */
2275 		boot = &ext.ptn[part];
2276 		partp = &boot->mbr_parts[0];
2277 		offset = ext_offset(part);
2278 	}
2279 
2280 	partp->mbrp_type = sysid;
2281 	partp->mbrp_start = htole32( start - offset);
2282 	partp->mbrp_size = htole32( size);
2283 	dos(start, &partp->mbrp_scyl, &partp->mbrp_shd, &partp->mbrp_ssect);
2284 	dos(start + size - 1,
2285 		    &partp->mbrp_ecyl, &partp->mbrp_ehd, &partp->mbrp_esect);
2286 #ifdef BOOTSEL
2287 	if (extended) {
2288 		boot->mbr_bootsel_magic = LE_MBR_BS_MAGIC;
2289 		strncpy(boot->mbr_bootsel.mbrbs_nametab[upart], tmp_bootmenu,
2290 			bootmenu_len);
2291 	} else {
2292 		/* We need to bootselect code installed in order to have
2293 		 * somewhere to safely write the menu tag.
2294 		 */
2295 		if (boot->mbr_bootsel_magic != LE_MBR_BS_MAGIC) {
2296 			if (f_flag ||
2297 			    yesno("The bootselect code is not installed, "
2298 				"do you want to install it now?"))
2299 				install_bootsel(MBR_BS_ACTIVE);
2300 		}
2301 		if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
2302 			strncpy(boot->mbr_bootsel.mbrbs_nametab[upart],
2303 				tmp_bootmenu, bootmenu_len);
2304 		}
2305 	}
2306 #endif
2307 
2308 	if (v_flag && !f_flag && yesno("Explicitly specify beg/end address?")) {
2309 		/* this really isn't a good idea.... */
2310 		int tsector, tcylinder, thead;
2311 
2312 		tcylinder = MBR_PCYL(partp->mbrp_scyl, partp->mbrp_ssect);
2313 		thead = partp->mbrp_shd;
2314 		tsector = MBR_PSECT(partp->mbrp_ssect);
2315 		tcylinder = decimal("beginning cylinder",
2316 				tcylinder, 0, 0, dos_cylinders - 1);
2317 		thead = decimal("beginning head",
2318 				thead, 0, 0, dos_heads - 1);
2319 		tsector = decimal("beginning sector",
2320 				tsector, 0, 1, dos_sectors);
2321 		partp->mbrp_scyl = DOSCYL(tcylinder);
2322 		partp->mbrp_shd = thead;
2323 		partp->mbrp_ssect = DOSSECT(tsector, tcylinder);
2324 
2325 		tcylinder = MBR_PCYL(partp->mbrp_ecyl, partp->mbrp_esect);
2326 		thead = partp->mbrp_ehd;
2327 		tsector = MBR_PSECT(partp->mbrp_esect);
2328 		tcylinder = decimal("ending cylinder",
2329 				tcylinder, 0, 0, dos_cylinders - 1);
2330 		thead = decimal("ending head",
2331 				thead, 0, 0, dos_heads - 1);
2332 		tsector = decimal("ending sector",
2333 				tsector, 0, 1, dos_sectors);
2334 		partp->mbrp_ecyl = DOSCYL(tcylinder);
2335 		partp->mbrp_ehd = thead;
2336 		partp->mbrp_esect = DOSSECT(tsector, tcylinder);
2337 	}
2338 
2339 	/* If we had to mark an extended partition as deleted because
2340 	 * another request would have overlapped it, now is the time
2341 	 * to do the actual delete.
2342 	 */
2343 	if (extended && f_flag) {
2344 		for (p = ext.num_ptn; --p >= 0;)
2345 			if (ext.ptn[p].mbr_parts[0].mbrp_type == 0)
2346 				delete_ext_ptn(p);
2347 	}
2348 	return 1;
2349 }
2350 
2351 static void
2352 print_geometry(void)
2353 {
2354 
2355 	if (sh_flag) {
2356 		printf("DISK=%s\n", disk);
2357 		printf("DLCYL=%d\nDLHEAD=%d\nDLSEC=%d\nDLSIZE=%"PRIdaddr"\n",
2358 			cylinders, heads, sectors, disksectors);
2359 		printf("BCYL=%d\nBHEAD=%d\nBSEC=%d\nBDLSIZE=%"PRIdaddr"\n",
2360 			dos_cylinders, dos_heads, dos_sectors, dos_disksectors);
2361 		printf("NUMEXTPTN=%d\n", ext.num_ptn);
2362 		return;
2363 	}
2364 
2365 	/* Not sh_flag */
2366 	printf("Disk: %s\n", disk);
2367 	printf("NetBSD disklabel disk geometry:\n");
2368 	printf("cylinders: %d, heads: %d, sectors/track: %d "
2369 	    "(%d sectors/cylinder)\ntotal sectors: %"PRIdaddr", "
2370 	    "bytes/sector: %zd\n\n", cylinders, heads, sectors,
2371 	    cylindersectors, disksectors, secsize);
2372 	printf("BIOS disk geometry:\n");
2373 	printf("cylinders: %d, heads: %d, sectors/track: %d "
2374 	    "(%d sectors/cylinder)\ntotal sectors: %"PRIdaddr"\n\n",
2375 	    dos_cylinders, dos_heads, dos_sectors, dos_cylindersectors,
2376 	    dos_disksectors);
2377 	printf("Partitions aligned to %d sector boundaries, offset %d\n\n",
2378 	    ptn_alignment, ptn_0_offset);
2379 }
2380 
2381 /* Find the first active partition, else return MBR_PART_COUNT */
2382 static int
2383 first_active(void)
2384 {
2385 	struct mbr_partition *partp = &mboot.mbr_parts[0];
2386 	int part;
2387 
2388 	for (part = 0; part < MBR_PART_COUNT; part++)
2389 		if (partp[part].mbrp_flag & MBR_PFLAG_ACTIVE)
2390 			return part;
2391 	return MBR_PART_COUNT;
2392 }
2393 
2394 static void
2395 change_active(int which)
2396 {
2397 	struct mbr_partition *partp;
2398 	int part;
2399 	int active = MBR_PART_COUNT;
2400 
2401 	partp = &mboot.mbr_parts[0];
2402 
2403 	if (a_flag && which != -1)
2404 		active = which;
2405 	else
2406 		active = first_active();
2407 	if (!f_flag) {
2408 		if (yesno("Do you want to change the active partition?")) {
2409 			printf ("Choosing %d will make no partition active.\n",
2410 			    MBR_PART_COUNT);
2411 			do {
2412 				active = decimal("active partition",
2413 						active, 0, 0, MBR_PART_COUNT);
2414 			} while (!yesno("Are you happy with this choice?"));
2415 		} else
2416 			return;
2417 	} else
2418 		if (active != MBR_PART_COUNT)
2419 			printf ("Making partition %d active.\n", active);
2420 
2421 	for (part = 0; part < MBR_PART_COUNT; part++)
2422 		partp[part].mbrp_flag &= ~MBR_PFLAG_ACTIVE;
2423 	if (active < MBR_PART_COUNT)
2424 		partp[active].mbrp_flag |= MBR_PFLAG_ACTIVE;
2425 }
2426 
2427 static void
2428 change_bios_geometry(void)
2429 {
2430 	print_geometry();
2431 	if (!yesno("Do you want to change our idea of what BIOS thinks?"))
2432 		return;
2433 
2434 #if defined(USE_DISKLIST)
2435 	if (dl != NULL) {
2436 		struct biosdisk_info *bip;
2437 		int i;
2438 
2439 		for (i = 0; i < dl->dl_nbiosdisks; i++) {
2440 			if (i == 0)
2441 				printf("\nGeometries of known disks:\n");
2442 			bip = &dl->dl_biosdisks[i];
2443 			printf("Disk %d: cylinders %u, heads %u, sectors %u"
2444 				" (%"PRIdaddr" sectors, %dMB)\n",
2445 			    i, bip->bi_cyl, bip->bi_head, bip->bi_sec,
2446 			    bip->bi_lbasecs, SEC_TO_MB(bip->bi_lbasecs));
2447 		}
2448 		printf("\n");
2449 	}
2450 #endif
2451 	do {
2452 		dos_cylinders = decimal("BIOS's idea of #cylinders",
2453 					dos_cylinders, 0, 0, MAXCYL);
2454 		dos_heads = decimal("BIOS's idea of #heads",
2455 					dos_heads, 0, 0, MAXHEAD);
2456 		dos_sectors = decimal("BIOS's idea of #sectors",
2457 					dos_sectors, 0, 1, MAXSECTOR);
2458 		print_geometry();
2459 	} while (!yesno("Are you happy with this choice?"));
2460 }
2461 
2462 
2463 /***********************************************\
2464 * Change real numbers into strange dos numbers	*
2465 \***********************************************/
2466 static void
2467 dos(int sector, unsigned char *cylinderp, unsigned char *headp,
2468     unsigned char *sectorp)
2469 {
2470 	int cylinder, head;
2471 
2472 	cylinder = sector / dos_cylindersectors;
2473 	sector -= cylinder * dos_cylindersectors;
2474 
2475 	head = sector / dos_sectors;
2476 	sector -= head * dos_sectors;
2477 	if (cylinder > 1023)
2478 		cylinder = 1023;
2479 
2480 	*cylinderp = DOSCYL(cylinder);
2481 	*headp = head;
2482 	*sectorp = DOSSECT(sector + 1, cylinder);
2483 }
2484 
2485 static int
2486 open_disk(int update)
2487 {
2488 	static char namebuf[MAXPATHLEN + 1];
2489 	int flags = update && disk_file == NULL ? O_RDWR : O_RDONLY;
2490 
2491 	if (!F_flag) {
2492 		fd = opendisk(disk, flags, namebuf, sizeof(namebuf), 0);
2493 		if (fd < 0) {
2494 			if (errno == ENODEV)
2495 				warnx("%s is not a character device", namebuf);
2496 			else
2497 				warn("cannot opendisk %s", namebuf);
2498 			return -1;
2499 		}
2500 		disk = namebuf;
2501 	} else {
2502 		fd = open(disk, flags, 0);
2503 		if (fd == -1) {
2504 			warn("cannot open %s", disk);
2505 			return -1;
2506 		}
2507 	}
2508 
2509 	if (get_params() == -1) {
2510 		close(fd);
2511 		fd = -1;
2512 		return -1;
2513 	}
2514 	if (disk_file != NULL) {
2515 		/* for testing: read/write data from a disk file */
2516 		wfd = open(disk_file, update ? O_RDWR|O_CREAT : O_RDONLY, 0777);
2517 		if (wfd == -1) {
2518 			warn("%s", disk_file);
2519 			close(fd);
2520 			fd = -1;
2521 			return -1;
2522 		}
2523 	} else
2524 		wfd = fd;
2525 	return 0;
2526 }
2527 
2528 static ssize_t
2529 read_disk(daddr_t sector, void *buf)
2530 {
2531 	ssize_t nr;
2532 
2533 	if (*rfd == -1)
2534 		errx(1, "read_disk(); fd == -1");
2535 
2536 	if (secsize <= 0)
2537 		errx(1, "read_disk(); secsize invalid");
2538 
2539 	off_t offs = sector * (off_t)secsize;
2540 	off_t mod = offs & (secsize - 1);
2541 	off_t rnd = offs & ~(secsize - 1);
2542 
2543 	if (lseek(*rfd, rnd, SEEK_SET) == (off_t)-1)
2544 		return -1;
2545 
2546 	if (secsize <= 512)
2547 		return read(*rfd, buf, secsize);
2548 
2549 	if ((nr = read(*rfd, iobuf, secsize)) != secsize)
2550 		return nr;
2551 
2552 	memcpy(buf, &iobuf[mod], 512);
2553 
2554 	return 512;
2555 }
2556 
2557 static ssize_t
2558 write_disk(daddr_t sector, void *buf)
2559 {
2560 	ssize_t nr;
2561 
2562 	if (wfd == -1)
2563 		errx(1, "write_disk(); wfd == -1");
2564 
2565 	off_t offs = sector * (off_t)secsize;
2566 	off_t mod = offs & (secsize - 1);
2567 	off_t rnd = offs & ~(secsize - 1);
2568 
2569 	if (lseek(wfd, rnd, SEEK_SET) == (off_t)-1)
2570 		return -1;
2571 
2572 	if (secsize == 512)
2573 		return write(wfd, buf, 512);
2574 
2575 	if ((nr = read(wfd, iobuf, secsize)) != secsize)
2576 		return nr;
2577 
2578 	if (lseek(wfd, rnd, SEEK_SET) == (off_t)-1)
2579 		return -1;
2580 
2581 	memcpy(&iobuf[mod], buf, 512);
2582 
2583 	if ((nr = write(wfd, iobuf, secsize)) != secsize)
2584 		return nr;
2585 
2586 	return 512;
2587 }
2588 
2589 static void
2590 guess_geometry(daddr_t _sectors)
2591 {
2592 	dos_sectors = MAXSECTOR;
2593 	dos_heads = MAXHEAD - 1;	/* some BIOS might use 256 */
2594 	dos_cylinders = _sectors / (MAXSECTOR * (MAXHEAD - 1));
2595 	if (dos_cylinders < 1)
2596 		dos_cylinders = 1;
2597 	else if (dos_cylinders > MAXCYL - 1)
2598 		dos_cylinders = MAXCYL - 1;
2599 }
2600 
2601 static int
2602 get_params(void)
2603 {
2604 	if (F_flag) {
2605 		struct stat st;
2606 		if (fstat(fd, &st) == -1) {
2607 			warn("%s: fstat", disk);
2608 			return -1;
2609 		}
2610 		if (st.st_size % 512 != 0) {
2611 			warnx("%s size (%ju) is not divisible "
2612 			    "by sector size (%d)", disk, (uintmax_t)st.st_size,
2613 			    512);
2614 		}
2615 		disklabel.d_secperunit = st.st_size / 512;
2616 		guess_geometry(disklabel.d_secperunit);
2617 		disklabel.d_ncylinders = dos_cylinders;
2618 		disklabel.d_ntracks = dos_heads;
2619 		disklabel.d_secsize = 512;
2620 		disklabel.d_nsectors = dos_sectors;
2621 	}
2622 #if !HAVE_NBTOOL_CONFIG_H
2623 	else if (ioctl(fd, DIOCGDEFLABEL, &disklabel) == -1) {
2624 		warn("%s: DIOCGDEFLABEL", disk);
2625 		if (ioctl(fd, DIOCGDINFO, &disklabel) == -1) {
2626 			warn("%s: DIOCGDINFO", disk);
2627 			return -1;
2628 		}
2629 	}
2630 #endif
2631 
2632 	disksectors = disklabel.d_secperunit;
2633 	cylinders = disklabel.d_ncylinders;
2634 	heads = disklabel.d_ntracks;
2635 	secsize = disklabel.d_secsize;
2636 	sectors = disklabel.d_nsectors;
2637 
2638 	/* pick up some defaults for the BIOS sizes */
2639 	if (sectors <= MAXSECTOR) {
2640 		dos_cylinders = cylinders;
2641 		dos_heads = heads;
2642 		dos_sectors = sectors;
2643 	} else {
2644 		/* guess - has to better than the above */
2645 		guess_geometry(disksectors);
2646 	}
2647 	dos_disksectors = disksectors;
2648 
2649 	return 0;
2650 }
2651 
2652 #ifdef BOOTSEL
2653 /*
2654  * Rather unfortunately the bootsel 'magic' number is at the end of the
2655  * the structure, and there is no checksum.  So when other operating
2656  * systems install mbr code by only writing the length of their code they
2657  * can overwrite part of the structure but keeping the magic number intact.
2658  * This code attempts to empirically detect this problem.
2659  */
2660 static int
2661 validate_bootsel(struct mbr_bootsel *mbs)
2662 {
2663 	unsigned int key = mbs->mbrbs_defkey;
2664 	unsigned int tmo;
2665 	size_t i, j;
2666 
2667 	if (v_flag)
2668 		return 0;
2669 
2670 	/*
2671 	 * Check default key is sane
2672 	 * - this is the most likely field to be stuffed
2673 	 * 16 disks and 16 bootable partitions seems enough!
2674 	 * (the keymap decode starts falling apart at that point)
2675 	 */
2676 	if (mbs->mbrbs_flags & MBR_BS_ASCII) {
2677 		if (key != 0 && !(key == '\r'
2678 		    || (key >= '1' && key < '1' + MAX_BIOS_DISKS)
2679 		    || (key >= 'a' && key < 'a' + MAX_BIOS_DISKS)))
2680 			return 1;
2681 	} else {
2682 		if (key != 0 && !(key == SCAN_ENTER
2683 		    || (key >= SCAN_1 && key < SCAN_1 + MAX_BIOS_DISKS)
2684 		    || (key >= SCAN_F1 && key < SCAN_F1 + MAX_BIOS_DISKS)))
2685 			return 1;
2686 	}
2687 
2688 	/* Checking the flags will lead to breakage... */
2689 
2690 	/* Timeout value is expected to be a multiple of a second */
2691 	tmo = htole16(mbs->mbrbs_timeo);
2692 	if (tmo != 0 && tmo != 0xffff && tmo != (10 * tmo + 9) / 182 * 182 / 10)
2693 		return 2;
2694 
2695 	/* Check the menu strings are printable */
2696 	/* Unfortunately they aren't zero filled... */
2697 	for (j = 0; j < __arraycount(mbs->mbrbs_nametab); ++j)
2698 	for (i = 0; i < sizeof(mbs->mbrbs_nametab[j]); i++) {
2699 		int c = (uint8_t)mbs->mbrbs_nametab[j][i];
2700 		if (c == 0 || isprint(c))
2701 			continue;
2702 		return 3;
2703 	}
2704 
2705 	return 0;
2706 }
2707 #endif
2708 
2709 static int
2710 read_s0(daddr_t offset, struct mbr_sector *boot)
2711 {
2712 	const char *tabletype = offset ? "extended" : "primary";
2713 #ifdef BOOTSEL
2714 	static int reported;
2715 #endif
2716 
2717 	if (read_disk(offset, boot) == -1) {
2718 		warn("Can't read %s partition table", tabletype);
2719 		return -1;
2720 	}
2721 	if (boot->mbr_magic != LE_MBR_MAGIC) {
2722 		if (F_flag && boot->mbr_magic == 0)
2723 			return -1;
2724 		warnx("%s partition table invalid, "
2725 		    "no magic in sector %"PRIdaddr, tabletype, offset);
2726 		return -1;
2727 
2728 	}
2729 #ifdef BOOTSEL
2730 	if (boot->mbr_bootsel_magic == LE_MBR_BS_MAGIC) {
2731 		/* mbr_bootsel in new location */
2732 		if (validate_bootsel(&boot->mbr_bootsel)) {
2733 			warnx("removing corrupt bootsel information");
2734 			boot->mbr_bootsel_magic = 0;
2735 		}
2736 		return 0;
2737 	}
2738 	if (boot->mbr_bootsel_magic != LE_MBR_MAGIC)
2739 		return 0;
2740 
2741 	/* mbr_bootsel in old location */
2742 	if (!reported)
2743 		warnx("%s partition table: using old-style bootsel information",
2744 		    tabletype);
2745 	reported = 1;
2746 	if (validate_bootsel((void *)((uint8_t *)boot + MBR_BS_OFFSET + 4))) {
2747 		warnx("%s bootsel information corrupt - ignoring", tabletype);
2748 		return 0;
2749 	}
2750 	memmove((uint8_t *)boot + MBR_BS_OFFSET,
2751 		(uint8_t *)boot + MBR_BS_OFFSET + 4,
2752 		sizeof(struct mbr_bootsel));
2753 	if ( ! (boot->mbr_bootsel.mbrbs_flags & MBR_BS_NEWMBR)) {
2754 			/* old style default key */
2755 		int id;
2756 			/* F1..F4 => ptn 0..3, F5+ => disk 0+ */
2757 		id = boot->mbr_bootsel.mbrbs_defkey;
2758 		id -= SCAN_F1;
2759 		if (id >= MBR_PART_COUNT)
2760 			id -= MBR_PART_COUNT; /* Use number of disk */
2761 		else if (mboot.mbr_parts[id].mbrp_type != 0)
2762 			id = le32toh(boot->mbr_parts[id].mbrp_start);
2763 		else
2764 			id = DEFAULT_ACTIVE;
2765 		boot->mbr_bootsel.mbrbs_defkey = id;
2766 	}
2767 	boot->mbr_bootsel_magic = LE_MBR_BS_MAGIC;
2768 		/* highlight that new bootsel code is necessary */
2769 	boot->mbr_bootsel.mbrbs_flags &= ~MBR_BS_NEWMBR;
2770 #endif /* BOOTSEL */
2771 	return 0;
2772 }
2773 
2774 static int
2775 write_mbr(void)
2776 {
2777 	int flag, i;
2778 	daddr_t offset;
2779 	int rval = -1;
2780 
2781 	/*
2782 	 * write enable label sector before write (if necessary),
2783 	 * disable after writing.
2784 	 * needed if the disklabel protected area also protects
2785 	 * sector 0. (e.g. empty disk)
2786 	 */
2787 	flag = 1;
2788 #if !HAVE_NBTOOL_CONFIG_H
2789 	if (wfd == fd && F_flag == 0 && ioctl(wfd, DIOCWLABEL, &flag) < 0)
2790 		warn("DIOCWLABEL");
2791 #endif
2792 	if (write_disk(0, &mboot) == -1) {
2793 		warn("Can't write fdisk partition table");
2794 		goto protect_label;
2795 	}
2796 	if (boot_installed)
2797 		for (i = bootsize; (i -= 0x200) > 0;)
2798 			if (write_disk(i / 0x200, &bootcode[i / 0x200]) == -1) {
2799 				warn("Can't write bootcode");
2800 				goto protect_label;
2801 			}
2802 	for (offset = 0, i = 0; i < ext.num_ptn; i++) {
2803 		if (write_disk(ext.base + offset, ext.ptn + i) == -1) {
2804 			warn("Can't write %dth extended partition", i);
2805 			goto protect_label;
2806 		}
2807 		offset = le32toh(ext.ptn[i].mbr_parts[1].mbrp_start);
2808 	}
2809 	rval = 0;
2810     protect_label:
2811 	flag = 0;
2812 #if !HAVE_NBTOOL_CONFIG_H
2813 	if (wfd == fd && F_flag == 0 && ioctl(wfd, DIOCWLABEL, &flag) < 0)
2814 		warn("DIOCWLABEL");
2815 #endif
2816 	return rval;
2817 }
2818 
2819 static int
2820 yesno(const char *str, ...)
2821 {
2822 	int ch, first;
2823 	va_list ap;
2824 
2825 	va_start(ap, str);
2826 	vprintf(str, ap);
2827 	va_end(ap);
2828 	printf(" [n] ");
2829 
2830 	first = ch = getchar();
2831 	while (ch != '\n' && ch != EOF)
2832 		ch = getchar();
2833 	if (ch == EOF)
2834 		errx(1, "EOF");
2835 	return first == 'y' || first == 'Y';
2836 }
2837 
2838 static int64_t
2839 decimal(const char *prompt, int64_t dflt, int flags, int64_t minval, int64_t maxval)
2840 {
2841 	int64_t acc = 0;
2842 	int valid;
2843 	int len;
2844 	char *cp;
2845 
2846 	for (;;) {
2847 		if (flags & DEC_SEC) {
2848 			printf("%s: [%" PRId64 "..%" PRId64 "cyl default: %" PRId64 ", %" PRId64 "cyl, %uMB] ",
2849 			    prompt, SEC_TO_CYL(minval), SEC_TO_CYL(maxval),
2850 			    dflt, SEC_TO_CYL(dflt), SEC_TO_MB(dflt));
2851 		} else
2852 			printf("%s: [%" PRId64 "..%" PRId64 " default: %" PRId64 "] ",
2853 			    prompt, minval, maxval, dflt);
2854 
2855 		if (!fgets(lbuf, LBUF, stdin))
2856 			errx(1, "EOF");
2857 		cp = lbuf;
2858 
2859 		cp += strspn(cp, " \t");
2860 		if (*cp == '\n')
2861 			return dflt;
2862 
2863 		if (cp[0] == '$' && cp[1] == '\n')
2864 			return maxval;
2865 
2866 		if (isdigit((unsigned char)*cp) || *cp == '-') {
2867 			acc = strtoll(lbuf, &cp, 10);
2868 			len = strcspn(cp, " \t\n");
2869 			valid = 0;
2870 			if (len != 0 && (flags & DEC_SEC)) {
2871 				if (!strncasecmp(cp, "gb", len)) {
2872 					acc *= 1024;
2873 					valid = 1;
2874 				}
2875 				if (valid || !strncasecmp(cp, "mb", len)) {
2876 					acc *= SEC_IN_1M;
2877 					/* round to whole number of cylinders */
2878 					acc += ptn_alignment / 2;
2879 					acc /= ptn_alignment;
2880 					valid = 1;
2881 				}
2882 				if (valid || !strncasecmp(cp, "cyl", len)) {
2883 					acc *= ptn_alignment;
2884 					/* adjustments for cylinder boundary */
2885 					if (acc == 0 && flags & DEC_RND_0)
2886 						acc += ptn_0_offset;
2887 					if (flags & DEC_RND)
2888 						acc += ptn_0_offset;
2889 					if (flags & DEC_RND_DOWN)
2890 						acc -= ptn_0_offset;
2891 					if (flags & DEC_RND_DOWN_2)
2892 						acc -= ptn_0_offset;
2893 					cp += len;
2894 				}
2895 			}
2896 		}
2897 
2898 		cp += strspn(cp, " \t");
2899 		if (*cp != '\n') {
2900 			lbuf[strlen(lbuf) - 1] = 0;
2901 			printf("%s is not a valid %s number.\n", lbuf,
2902 			    flags & DEC_SEC ? "sector" : "decimal");
2903 			continue;
2904 		}
2905 
2906 		if (acc >= minval && acc <= maxval)
2907 			return acc;
2908 		printf("%" PRId64 " is not between %" PRId64 " and %" PRId64 ".\n", acc, minval, maxval);
2909 	}
2910 }
2911 
2912 static int
2913 ptn_id(const char *prompt, int *extended)
2914 {
2915 	unsigned int acc = 0;
2916 	char *cp;
2917 
2918 	for (;; printf("%s is not a valid partition number.\n", lbuf)) {
2919 		printf("%s: [none] ", prompt);
2920 
2921 		if (!fgets(lbuf, LBUF, stdin))
2922 			errx(1, "EOF");
2923 		lbuf[strlen(lbuf)-1] = '\0';
2924 		cp = lbuf;
2925 
2926 		cp += strspn(cp, " \t");
2927 		*extended = 0;
2928 		if (*cp == 0)
2929 			return -1;
2930 
2931 		if (*cp == 'E' || *cp == 'e') {
2932 			cp++;
2933 			*extended = 1;
2934 		}
2935 
2936 		acc = strtoul(cp, &cp, 10);
2937 
2938 		cp += strspn(cp, " \t");
2939 		if (*cp != '\0')
2940 			continue;
2941 
2942 		if (*extended || acc < MBR_PART_COUNT)
2943 			return acc;
2944 	}
2945 }
2946 
2947 #ifdef BOOTSEL
2948 static void
2949 string(const char *prompt, int length, char *buf)
2950 {
2951 	int len;
2952 
2953 	for (;;) {
2954 		printf("%s: [%.*s] (space to clear)", prompt, length, buf);
2955 
2956 		if (!fgets(lbuf, LBUF, stdin))
2957 			errx(1, "EOF");
2958 		len = strlen(lbuf);
2959 		if (len <= 1)
2960 			/* unchanged if just <enter> */
2961 			return;
2962 		/* now strip trailing spaces, <space><enter> deletes string */
2963 		do
2964 			lbuf[--len] = 0;
2965 		while (len != 0 && lbuf[len - 1] == ' ');
2966 		if (len < length)
2967 			break;
2968 		printf("'%s' is longer than %d characters.\n",
2969 		    lbuf, length - 1);
2970 	}
2971 	strncpy(buf, lbuf, length);
2972 }
2973 #endif
2974 
2975 static int
2976 type_match(const void *key, const void *item)
2977 {
2978 	const int *idp = key;
2979 	const struct mbr_ptype *ptr = item;
2980 
2981 	if (*idp < ptr->id)
2982 		return -1;
2983 	if (*idp > ptr->id)
2984 		return 1;
2985 	return 0;
2986 }
2987 
2988 static const char *
2989 get_type(int type)
2990 {
2991 	const struct mbr_ptype *ptr;
2992 
2993 	ptr = bsearch(&type, mbr_ptypes, KNOWN_SYSIDS,
2994 	    sizeof(mbr_ptypes[0]), type_match);
2995 	if (ptr == NULL)
2996 		return "unknown";
2997 	return ptr->name;
2998 }
2999 
3000 static int
3001 read_gpt(daddr_t offset, struct gpt_hdr *gptp)
3002 {
3003 	char buf[512];
3004 	struct gpt_hdr *hdr = (void *)buf;
3005 	const char *tabletype = GPT_TYPE(offset);
3006 
3007 	if (read_disk(offset, buf) == -1) {
3008 		warn("Can't read %s GPT header", tabletype);
3009 		return -1;
3010 	}
3011 	(void)memcpy(gptp, buf, GPT_HDR_SIZE);
3012 
3013 	/* GPT CRC should be calculated with CRC field preset to zero */
3014 	hdr->hdr_crc_self = 0;
3015 
3016 	if (memcmp(gptp->hdr_sig, GPT_HDR_SIG, sizeof(gptp->hdr_sig))
3017 	    || gptp->hdr_lba_self != (uint64_t)offset
3018 	    || crc32(0, (void *)hdr, gptp->hdr_size) != gptp->hdr_crc_self) {
3019 		/* not a GPT */
3020 		(void)memset(gptp, 0, GPT_HDR_SIZE);
3021 	}
3022 
3023 	if (v_flag && gptp->hdr_size != 0) {
3024 		printf("Found %s GPT header CRC %"PRIu32" "
3025 		    "at sector %"PRIdaddr", backup at %"PRIdaddr"\n",
3026 		    tabletype, gptp->hdr_crc_self, offset, gptp->hdr_lba_alt);
3027 	}
3028 	return gptp->hdr_size;
3029 
3030 }
3031 
3032 static int
3033 delete_gpt(struct gpt_hdr *gptp)
3034 {
3035 	char buf[512];
3036 	struct gpt_hdr *hdr = (void *)buf;
3037 
3038 	if (g_flag)
3039 		return 0;	/* preserve existing GPT headers */
3040 
3041 	if (gptp->hdr_size == 0)
3042 		return 0;
3043 
3044 	/* don't accidently overwrite something important */
3045 	if (gptp->hdr_lba_self != GPT_HDR_BLKNO &&
3046 	    gptp->hdr_lba_self != (uint64_t)disksectors - 1) {
3047 		warnx("given GPT header location doesn't seem correct");
3048 		return -1;
3049 	}
3050 
3051 	(void)memcpy(buf, gptp, GPT_HDR_SIZE);
3052 	/*
3053 	 * Don't really delete GPT, just "disable" it, so it can
3054 	 * be recovered later in case of mistake or something
3055 	 */
3056 	(void)memset(hdr->hdr_sig, 0, sizeof(gptp->hdr_sig));
3057 	if (write_disk(gptp->hdr_lba_self, hdr) == -1) {
3058 		warn("can't delete %s GPT header",
3059 		    GPT_TYPE(gptp->hdr_lba_self));
3060 		return -1;
3061 	}
3062 	(void)memset(gptp, 0, GPT_HDR_SIZE);
3063 	return 1;
3064 }
3065