fdisk.c revision 187246 
1/*
2 * Mach Operating System
3 * Copyright (c) 1992 Carnegie Mellon University
4 * All Rights Reserved.
5 *
6 * Permission to use, copy, modify and distribute this software and its
7 * documentation is hereby granted, provided that both the copyright
8 * notice and this permission notice appear in all copies of the
9 * software, derivative works or modified versions, and any portions
10 * thereof, and that both notices appear in supporting documentation.
11 *
12 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
13 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15 *
16 * Carnegie Mellon requests users of this software to return to
17 *
18 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
19 *  School of Computer Science
20 *  Carnegie Mellon University
21 *  Pittsburgh PA 15213-3890
22 *
23 * any improvements or extensions that they make and grant Carnegie Mellon
24 * the rights to redistribute these changes.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sbin/fdisk/fdisk.c 187246 2009-01-14 21:31:09Z luigi $");
29
30#include <sys/disk.h>
31#include <sys/disklabel.h>
32#include <sys/diskmbr.h>
33#include <sys/endian.h>
34#include <sys/param.h>
35#include <sys/stat.h>
36#include <sys/mount.h>
37#include <ctype.h>
38#include <fcntl.h>
39#include <err.h>
40#include <errno.h>
41#include <libgeom.h>
42#include <paths.h>
43#include <regex.h>
44#include <stdint.h>
45#include <stdio.h>
46#include <stdlib.h>
47#include <string.h>
48#include <unistd.h>
49
50int iotest;
51
52#define LBUF 100
53static char lbuf[LBUF];
54
55/*
56 *
57 * Ported to 386bsd by Julian Elischer  Thu Oct 15 20:26:46 PDT 1992
58 *
59 * 14-Dec-89  Robert Baron (rvb) at Carnegie-Mellon University
60 *	Copyright (c) 1989	Robert. V. Baron
61 *	Created.
62 */
63
64#define Decimal(str, ans, tmp) if (decimal(str, &tmp, ans)) ans = tmp
65
66#define RoundCyl(x) ((((x) + cylsecs - 1) / cylsecs) * cylsecs)
67
68#define MAX_SEC_SIZE 2048	/* maximum section size that is supported */
69#define MIN_SEC_SIZE 512	/* the sector size to start sensing at */
70static int secsize = 0;		/* the sensed sector size */
71
72static char *disk;
73
74static int cyls, sectors, heads, cylsecs, disksecs;
75
76struct mboot {
77	unsigned char *bootinst;  /* boot code */
78	off_t bootinst_size;
79	struct	dos_partition parts[NDOSPART];
80};
81
82static struct mboot mboot;
83static int fd;
84
85#define ACTIVE 0x80
86
87static uint dos_cyls;
88static uint dos_heads;
89static uint dos_sectors;
90static uint dos_cylsecs;
91
92#define DOSSECT(s,c) ((s & 0x3f) | ((c >> 2) & 0xc0))
93#define DOSCYL(c)	(c & 0xff)
94
95#define MAX_ARGS	10
96
97static int	current_line_number;
98
99static int	geom_processed = 0;
100static int	part_processed = 0;
101static int	active_processed = 0;
102
103typedef struct cmd {
104    char		cmd;
105    int			n_args;
106    struct arg {
107	char	argtype;
108	int	arg_val;
109    }			args[MAX_ARGS];
110} CMD;
111
112static int B_flag  = 0;		/* replace boot code */
113static int I_flag  = 0;		/* use entire disk for FreeBSD */
114static int a_flag  = 0;		/* set active partition */
115static char *b_flag = NULL;	/* path to boot code */
116static int i_flag  = 0;		/* replace partition data */
117static int q_flag  = 0;		/* Be quiet */
118static int u_flag  = 0;		/* update partition data */
119static int s_flag  = 0;		/* Print a summary and exit */
120static int t_flag  = 0;		/* test only */
121static char *f_flag = NULL;	/* Read config info from file */
122static int v_flag  = 0;		/* Be verbose */
123static int print_config_flag = 0;
124
125/*
126 * A list of partition types, probably outdated.
127 */
128static const char *const part_types[256] = {
129	[0x00] = "unused",
130	[0x01] = "Primary DOS with 12 bit FAT",
131	[0x02] = "XENIX / file system",
132	[0x03] = "XENIX /usr file system",
133	[0x04] = "Primary DOS with 16 bit FAT (< 32MB)",
134	[0x05] = "Extended DOS",
135	[0x06] = "Primary 'big' DOS (>= 32MB)",
136	[0x07] = "OS/2 HPFS, NTFS, QNX-2 (16 bit) or Advanced UNIX",
137	[0x08] = "AIX file system or SplitDrive",
138	[0x09] = "AIX boot partition or Coherent",
139	[0x0A] = "OS/2 Boot Manager, OPUS or Coherent swap",
140	[0x0B] = "DOS or Windows 95 with 32 bit FAT",
141	[0x0C] = "DOS or Windows 95 with 32 bit FAT (LBA)",
142	[0x0E] = "Primary 'big' DOS (>= 32MB, LBA)",
143	[0x0F] = "Extended DOS (LBA)",
144	[0x10] = "OPUS",
145	[0x11] = "OS/2 BM: hidden DOS with 12-bit FAT",
146	[0x12] = "Compaq diagnostics",
147	[0x14] = "OS/2 BM: hidden DOS with 16-bit FAT (< 32MB)",
148	[0x16] = "OS/2 BM: hidden DOS with 16-bit FAT (>= 32MB)",
149	[0x17] = "OS/2 BM: hidden IFS (e.g. HPFS)",
150	[0x18] = "AST Windows swapfile",
151	[0x24] = "NEC DOS",
152	[0x3C] = "PartitionMagic recovery",
153	[0x39] = "plan9",
154	[0x40] = "VENIX 286",
155	[0x41] = "Linux/MINIX (sharing disk with DRDOS)",
156	[0x42] = "SFS or Linux swap (sharing disk with DRDOS)",
157	[0x43] = "Linux native (sharing disk with DRDOS)",
158	[0x4D] = "QNX 4.2 Primary",
159	[0x4E] = "QNX 4.2 Secondary",
160	[0x4F] = "QNX 4.2 Tertiary",
161	[0x50] = "DM (disk manager)",
162	[0x51] = "DM6 Aux1 (or Novell)",
163	[0x52] = "CP/M or Microport SysV/AT",
164	[0x53] = "DM6 Aux3",
165	[0x54] = "DM6",
166	[0x55] = "EZ-Drive (disk manager)",
167	[0x56] = "Golden Bow (disk manager)",
168	[0x5c] = "Priam Edisk (disk manager)", /* according to S. Widlake */
169	[0x61] = "SpeedStor",
170	[0x63] = "System V/386 (such as ISC UNIX), GNU HURD or Mach",
171	[0x64] = "Novell Netware/286 2.xx",
172	[0x65] = "Novell Netware/386 3.xx",
173	[0x70] = "DiskSecure Multi-Boot",
174	[0x75] = "PCIX",
175	[0x77] = "QNX4.x",
176	[0x78] = "QNX4.x 2nd part",
177	[0x79] = "QNX4.x 3rd part",
178	[0x80] = "Minix until 1.4a",
179	[0x81] = "Minix since 1.4b, early Linux partition or Mitac disk manager",
180	[0x82] = "Linux swap or Solaris x86",
181	[0x83] = "Linux native",
182	[0x84] = "OS/2 hidden C: drive",
183	[0x85] = "Linux extended",
184	[0x86] = "NTFS volume set??",
185	[0x87] = "NTFS volume set??",
186	[0x93] = "Amoeba file system",
187	[0x94] = "Amoeba bad block table",
188	[0x9F] = "BSD/OS",
189	[0xA0] = "Suspend to Disk",
190	[0xA5] = "FreeBSD/NetBSD/386BSD",
191	[0xA6] = "OpenBSD",
192	[0xA7] = "NeXTSTEP",
193	[0xA9] = "NetBSD",
194	[0xAC] = "IBM JFS",
195	[0xAF] = "HFS+",
196	[0xB7] = "BSDI BSD/386 file system",
197	[0xB8] = "BSDI BSD/386 swap",
198	[0xBE] = "Solaris x86 boot",
199	[0xBF] = "Solaris x86 (new)",
200	[0xC1] = "DRDOS/sec with 12-bit FAT",
201	[0xC4] = "DRDOS/sec with 16-bit FAT (< 32MB)",
202	[0xC6] = "DRDOS/sec with 16-bit FAT (>= 32MB)",
203	[0xC7] = "Syrinx",
204	[0xDB] = "CP/M, Concurrent CP/M, Concurrent DOS or CTOS",
205	[0xE1] = "DOS access or SpeedStor with 12-bit FAT extended partition",
206	[0xE3] = "DOS R/O or SpeedStor",
207	[0xE4] = "SpeedStor with 16-bit FAT extended partition < 1024 cyl.",
208	[0xEB] = "BeOS file system",
209	[0xEE] = "EFI GPT",
210	[0xEF] = "EFI System Partition",
211	[0xF1] = "SpeedStor",
212	[0xF2] = "DOS 3.3+ Secondary",
213	[0xF4] = "SpeedStor large partition",
214	[0xFE] = "SpeedStor >1024 cyl. or LANstep",
215	[0xFF] = "Xenix bad blocks table",
216};
217
218static const char *
219get_type(int t)
220{
221	const char *ret;
222
223	ret = (t >= 0 && t <= 255) ? part_types[t] : NULL;
224	return ret ? ret : "unknown";
225}
226
227
228static void print_s0(void);
229static void print_part(const struct dos_partition *);
230static void init_sector0(unsigned long start);
231static void init_boot(void);
232static void change_part(int i);
233static void print_params(void);
234static void change_active(int which);
235static void change_code(void);
236static void get_params_to_use(void);
237static char *get_rootdisk(void);
238static void dos(struct dos_partition *partp);
239static int open_disk(int flag);
240static ssize_t read_disk(off_t sector, void *buf);
241static int write_disk(off_t sector, void *buf);
242static int get_params(void);
243static int read_s0(void);
244static int write_s0(void);
245static int ok(const char *str);
246static int decimal(const char *str, int *num, int deflt);
247static int read_config(char *config_file);
248static void reset_boot(void);
249static int sanitize_partition(struct dos_partition *);
250static void usage(void);
251
252int
253main(int argc, char *argv[])
254{
255	int	c, i;
256	int	partition = -1;
257	struct	dos_partition *partp;
258
259	while ((c = getopt(argc, argv, "BIab:f:ipqstuv1234")) != -1)
260		switch (c) {
261		case 'B':
262			B_flag = 1;
263			break;
264		case 'I':
265			I_flag = 1;
266			break;
267		case 'a':
268			a_flag = 1;
269			break;
270		case 'b':
271			b_flag = optarg;
272			break;
273		case 'f':
274			f_flag = optarg;
275			break;
276		case 'i':
277			i_flag = 1;
278			break;
279		case 'p':
280			print_config_flag = 1;
281			break;
282		case 'q':
283			q_flag = 1;
284			break;
285		case 's':
286			s_flag = 1;
287			break;
288		case 't':
289			t_flag = 1;
290			break;
291		case 'u':
292			u_flag = 1;
293			break;
294		case 'v':
295			v_flag = 1;
296			break;
297		case '1':
298		case '2':
299		case '3':
300		case '4':
301			partition = c - '0';
302			break;
303		default:
304			usage();
305		}
306	if (f_flag || i_flag)
307		u_flag = 1;
308	if (t_flag)
309		v_flag = 1;
310	argc -= optind;
311	argv += optind;
312
313	if (argc == 0) {
314		disk = get_rootdisk();
315	} else {
316		disk = g_device_path(argv[0]);
317		if (disk == NULL)
318			err(1, "unable to get correct path for %s", argv[0]);
319	}
320	if (open_disk(u_flag) < 0)
321		err(1, "cannot open disk %s", disk);
322
323	/* (abu)use mboot.bootinst to probe for the sector size */
324	if ((mboot.bootinst = malloc(MAX_SEC_SIZE)) == NULL)
325		err(1, "cannot allocate buffer to determine disk sector size");
326	if (read_disk(0, mboot.bootinst) == -1)
327		errx(1, "could not detect sector size");
328	free(mboot.bootinst);
329	mboot.bootinst = NULL;
330
331	if (print_config_flag) {
332		if (read_s0())
333			err(1, "read_s0");
334
335		printf("# %s\n", disk);
336		printf("g c%d h%d s%d\n", dos_cyls, dos_heads, dos_sectors);
337
338		for (i = 0; i < NDOSPART; i++) {
339			partp = &mboot.parts[i];
340
341			if (partp->dp_start == 0 && partp->dp_size == 0)
342				continue;
343
344			printf("p %d 0x%02x %lu %lu\n", i + 1, partp->dp_typ,
345			    (u_long)partp->dp_start, (u_long)partp->dp_size);
346
347			/* Fill flags for the partition. */
348			if (partp->dp_flag & 0x80)
349				printf("a %d\n", i + 1);
350		}
351		exit(0);
352	}
353	if (s_flag) {
354		if (read_s0())
355			err(1, "read_s0");
356		printf("%s: %d cyl %d hd %d sec\n", disk, dos_cyls, dos_heads,
357		    dos_sectors);
358		printf("Part  %11s %11s Type Flags\n", "Start", "Size");
359		for (i = 0; i < NDOSPART; i++) {
360			partp = &mboot.parts[i];
361			if (partp->dp_start == 0 && partp->dp_size == 0)
362				continue;
363			printf("%4d: %11lu %11lu 0x%02x 0x%02x\n", i + 1,
364			    (u_long) partp->dp_start,
365			    (u_long) partp->dp_size, partp->dp_typ,
366			    partp->dp_flag);
367		}
368		exit(0);
369	}
370
371	printf("******* Working on device %s *******\n",disk);
372
373	if (I_flag) {
374		read_s0();
375		reset_boot();
376		partp = &mboot.parts[0];
377		partp->dp_typ = DOSPTYP_386BSD;
378		partp->dp_flag = ACTIVE;
379		partp->dp_start = dos_sectors;
380		partp->dp_size = (disksecs / dos_cylsecs) * dos_cylsecs -
381		    dos_sectors;
382		dos(partp);
383		if (v_flag)
384			print_s0();
385		if (!t_flag)
386			write_s0();
387		exit(0);
388	}
389	if (f_flag) {
390	    if (read_s0() || i_flag)
391		reset_boot();
392	    if (!read_config(f_flag))
393		exit(1);
394	    if (v_flag)
395		print_s0();
396	    if (!t_flag)
397		write_s0();
398	} else {
399	    if(u_flag)
400		get_params_to_use();
401	    else
402		print_params();
403
404	    if (read_s0())
405		init_sector0(dos_sectors);
406
407	    printf("Media sector size is %d\n", secsize);
408	    printf("Warning: BIOS sector numbering starts with sector 1\n");
409	    printf("Information from DOS bootblock is:\n");
410	    if (partition == -1)
411		for (i = 1; i <= NDOSPART; i++)
412		    change_part(i);
413	    else
414		change_part(partition);
415
416	    if (u_flag || a_flag)
417		change_active(partition);
418
419	    if (B_flag)
420		change_code();
421
422	    if (u_flag || a_flag || B_flag) {
423		if (!t_flag) {
424		    printf("\nWe haven't changed the partition table yet.  ");
425		    printf("This is your last chance.\n");
426		}
427		print_s0();
428		if (!t_flag) {
429		    if (ok("Should we write new partition table?"))
430			write_s0();
431		} else {
432		    printf("\n-t flag specified -- partition table not written.\n");
433		}
434	    }
435	}
436
437	exit(0);
438}
439
440static void
441usage()
442{
443	fprintf(stderr, "%s%s",
444		"usage: fdisk [-BIaipqstu] [-b bootcode] [-1234] [disk]\n",
445 		"       fdisk -f configfile [-itv] [disk]\n");
446        exit(1);
447}
448
449static void
450print_s0(void)
451{
452	int	i;
453
454	print_params();
455	printf("Information from DOS bootblock is:\n");
456	for (i = 1; i <= NDOSPART; i++) {
457		printf("%d: ", i);
458		print_part(&mboot.parts[i - 1]);
459	}
460}
461
462static struct dos_partition mtpart;
463
464static void
465print_part(const struct dos_partition *partp)
466{
467	u_int64_t part_mb;
468
469	if (!bcmp(partp, &mtpart, sizeof (struct dos_partition))) {
470		printf("<UNUSED>\n");
471		return;
472	}
473	/*
474	 * Be careful not to overflow.
475	 */
476	part_mb = partp->dp_size;
477	part_mb *= secsize;
478	part_mb /= (1024 * 1024);
479	printf("sysid %d (%#04x),(%s)\n", partp->dp_typ, partp->dp_typ,
480	    get_type(partp->dp_typ));
481	printf("    start %lu, size %lu (%ju Meg), flag %x%s\n",
482		(u_long)partp->dp_start,
483		(u_long)partp->dp_size,
484		(uintmax_t)part_mb,
485		partp->dp_flag,
486		partp->dp_flag == ACTIVE ? " (active)" : "");
487	printf("\tbeg: cyl %d/ head %d/ sector %d;\n\tend: cyl %d/ head %d/ sector %d\n"
488		,DPCYL(partp->dp_scyl, partp->dp_ssect)
489		,partp->dp_shd
490		,DPSECT(partp->dp_ssect)
491		,DPCYL(partp->dp_ecyl, partp->dp_esect)
492		,partp->dp_ehd
493		,DPSECT(partp->dp_esect));
494}
495
496
497static void
498init_boot(void)
499{
500#ifndef __ia64__
501	const char *fname;
502	int fdesc, n;
503	struct stat sb;
504
505	fname = b_flag ? b_flag : "/boot/mbr";
506	if ((fdesc = open(fname, O_RDONLY)) == -1 ||
507	    fstat(fdesc, &sb) == -1)
508		err(1, "%s", fname);
509	if ((mboot.bootinst_size = sb.st_size) % secsize != 0)
510		errx(1, "%s: length must be a multiple of sector size", fname);
511	if (mboot.bootinst != NULL)
512		free(mboot.bootinst);
513	if ((mboot.bootinst = malloc(mboot.bootinst_size = sb.st_size)) == NULL)
514		errx(1, "%s: unable to allocate read buffer", fname);
515	if ((n = read(fdesc, mboot.bootinst, mboot.bootinst_size)) == -1 ||
516	    close(fdesc))
517		err(1, "%s", fname);
518	if (n != mboot.bootinst_size)
519		errx(1, "%s: short read", fname);
520#else
521	if (mboot.bootinst != NULL)
522		free(mboot.bootinst);
523	mboot.bootinst_size = secsize;
524	if ((mboot.bootinst = malloc(mboot.bootinst_size)) == NULL)
525		errx(1, "unable to allocate boot block buffer");
526	memset(mboot.bootinst, 0, mboot.bootinst_size);
527	le16enc(&mboot.bootinst[DOSMAGICOFFSET], DOSMAGIC);
528#endif
529}
530
531
532static void
533init_sector0(unsigned long start)
534{
535	struct dos_partition *partp = &mboot.parts[0];
536
537	init_boot();
538
539	partp->dp_typ = DOSPTYP_386BSD;
540	partp->dp_flag = ACTIVE;
541	start = ((start + dos_sectors - 1) / dos_sectors) * dos_sectors;
542	if(start == 0)
543		start = dos_sectors;
544	partp->dp_start = start;
545	partp->dp_size = (disksecs / dos_cylsecs) * dos_cylsecs - start;
546
547	dos(partp);
548}
549
550static void
551change_part(int i)
552{
553    struct dos_partition *partp = &mboot.parts[i - 1];
554
555    printf("The data for partition %d is:\n", i);
556    print_part(partp);
557
558    if (u_flag && ok("Do you want to change it?")) {
559	int tmp;
560
561	if (i_flag) {
562	    bzero(partp, sizeof (*partp));
563	    if (i == 1) {
564		init_sector0(1);
565		printf("\nThe static data for the slice 1 has been reinitialized to:\n");
566		print_part(partp);
567	    }
568	}
569
570	do {
571		Decimal("sysid (165=FreeBSD)", partp->dp_typ, tmp);
572		Decimal("start", partp->dp_start, tmp);
573		Decimal("size", partp->dp_size, tmp);
574		if (!sanitize_partition(partp)) {
575			warnx("ERROR: failed to adjust; setting sysid to 0");
576			partp->dp_typ = 0;
577		}
578
579		if (ok("Explicitly specify beg/end address ?"))
580		{
581			int	tsec,tcyl,thd;
582			tcyl = DPCYL(partp->dp_scyl,partp->dp_ssect);
583			thd = partp->dp_shd;
584			tsec = DPSECT(partp->dp_ssect);
585			Decimal("beginning cylinder", tcyl, tmp);
586			Decimal("beginning head", thd, tmp);
587			Decimal("beginning sector", tsec, tmp);
588			partp->dp_scyl = DOSCYL(tcyl);
589			partp->dp_ssect = DOSSECT(tsec,tcyl);
590			partp->dp_shd = thd;
591
592			tcyl = DPCYL(partp->dp_ecyl,partp->dp_esect);
593			thd = partp->dp_ehd;
594			tsec = DPSECT(partp->dp_esect);
595			Decimal("ending cylinder", tcyl, tmp);
596			Decimal("ending head", thd, tmp);
597			Decimal("ending sector", tsec, tmp);
598			partp->dp_ecyl = DOSCYL(tcyl);
599			partp->dp_esect = DOSSECT(tsec,tcyl);
600			partp->dp_ehd = thd;
601		} else
602			dos(partp);
603
604		print_part(partp);
605	} while (!ok("Are we happy with this entry?"));
606    }
607}
608
609static void
610print_params()
611{
612	printf("parameters extracted from in-core disklabel are:\n");
613	printf("cylinders=%d heads=%d sectors/track=%d (%d blks/cyl)\n\n"
614			,cyls,heads,sectors,cylsecs);
615	if (dos_cyls > 1023 || dos_heads > 255 || dos_sectors > 63)
616		printf("Figures below won't work with BIOS for partitions not in cyl 1\n");
617	printf("parameters to be used for BIOS calculations are:\n");
618	printf("cylinders=%d heads=%d sectors/track=%d (%d blks/cyl)\n\n"
619		,dos_cyls,dos_heads,dos_sectors,dos_cylsecs);
620}
621
622static void
623change_active(int which)
624{
625	struct dos_partition *partp = &mboot.parts[0];
626	int active, i, new, tmp;
627
628	active = -1;
629	for (i = 0; i < NDOSPART; i++) {
630		if ((partp[i].dp_flag & ACTIVE) == 0)
631			continue;
632		printf("Partition %d is marked active\n", i + 1);
633		if (active == -1)
634			active = i + 1;
635	}
636	if (a_flag && which != -1)
637		active = which;
638	else if (active == -1)
639		active = 1;
640
641	if (!ok("Do you want to change the active partition?"))
642		return;
643setactive:
644	do {
645		new = active;
646		Decimal("active partition", new, tmp);
647		if (new < 1 || new > 4) {
648			printf("Active partition number must be in range 1-4."
649					"  Try again.\n");
650			goto setactive;
651		}
652		active = new;
653	} while (!ok("Are you happy with this choice"));
654	for (i = 0; i < NDOSPART; i++)
655		partp[i].dp_flag = 0;
656	if (active > 0 && active <= NDOSPART)
657		partp[active-1].dp_flag = ACTIVE;
658}
659
660static void
661change_code()
662{
663	if (ok("Do you want to change the boot code?"))
664		init_boot();
665}
666
667void
668get_params_to_use()
669{
670	int	tmp;
671	print_params();
672	if (ok("Do you want to change our idea of what BIOS thinks ?"))
673	{
674		do
675		{
676			Decimal("BIOS's idea of #cylinders", dos_cyls, tmp);
677			Decimal("BIOS's idea of #heads", dos_heads, tmp);
678			Decimal("BIOS's idea of #sectors", dos_sectors, tmp);
679			dos_cylsecs = dos_heads * dos_sectors;
680			print_params();
681		}
682		while(!ok("Are you happy with this choice"));
683	}
684}
685
686
687/***********************************************\
688* Change real numbers into strange dos numbers	*
689\***********************************************/
690static void
691dos(struct dos_partition *partp)
692{
693	int cy, sec;
694	u_int32_t end;
695
696	if (partp->dp_typ == 0 && partp->dp_start == 0 && partp->dp_size == 0) {
697		memcpy(partp, &mtpart, sizeof(*partp));
698		return;
699	}
700
701	/* Start c/h/s. */
702	partp->dp_shd = partp->dp_start % dos_cylsecs / dos_sectors;
703	cy = partp->dp_start / dos_cylsecs;
704	sec = partp->dp_start % dos_sectors + 1;
705	partp->dp_scyl = DOSCYL(cy);
706	partp->dp_ssect = DOSSECT(sec, cy);
707
708	/* End c/h/s. */
709	end = partp->dp_start + partp->dp_size - 1;
710	partp->dp_ehd = end % dos_cylsecs / dos_sectors;
711	cy = end / dos_cylsecs;
712	sec = end % dos_sectors + 1;
713	partp->dp_ecyl = DOSCYL(cy);
714	partp->dp_esect = DOSSECT(sec, cy);
715}
716
717static int
718open_disk(int flag)
719{
720	int rwmode;
721
722	/* Write mode if one of these flags are set. */
723	rwmode = (a_flag || I_flag || B_flag || flag);
724	fd = g_open(disk, rwmode);
725	/* If the mode fails, try read-only if we didn't. */
726	if (fd == -1 && errno == EPERM && rwmode)
727		fd = g_open(disk, 0);
728	if (fd == -1 && errno == ENXIO)
729		return -2;
730	if (fd == -1) {
731		warnx("can't open device %s", disk);
732		return -1;
733	}
734	if (get_params() == -1) {
735		warnx("can't get disk parameters on %s", disk);
736		return -1;
737	}
738	return fd;
739}
740
741static ssize_t
742read_disk(off_t sector, void *buf)
743{
744
745	lseek(fd, (sector * 512), 0);
746	if (secsize == 0)
747		for (secsize = MIN_SEC_SIZE; secsize <= MAX_SEC_SIZE;
748		     secsize *= 2) {
749			/* try the read */
750			int size = read(fd, buf, secsize);
751			if (size == secsize)
752				/* it worked so return */
753				return secsize;
754		}
755	else
756		return read(fd, buf, secsize);
757
758	/* we failed to read at any of the sizes */
759	return -1;
760}
761
762static int
763write_disk(off_t sector, void *buf)
764{
765	int error;
766	struct gctl_req *grq;
767	const char *errmsg;
768	char fbuf[BUFSIZ], *pname;
769	int i, fdw;
770
771	grq = gctl_get_handle();
772	gctl_ro_param(grq, "verb", -1, "write MBR");
773	gctl_ro_param(grq, "class", -1, "MBR");
774	pname = g_providername(fd);
775	if (pname == NULL) {
776		warn("Error getting providername for %s", disk);
777		return (-1);
778	}
779	gctl_ro_param(grq, "geom", -1, pname);
780	gctl_ro_param(grq, "data", secsize, buf);
781	errmsg = gctl_issue(grq);
782	free(pname);
783	if (errmsg == NULL) {
784		gctl_free(grq);
785		return(0);
786	}
787	if (!q_flag)	/* GEOM errors are benign, not all devices supported */
788		warnx("%s", errmsg);
789	gctl_free(grq);
790
791	error = pwrite(fd, buf, secsize, (sector * 512));
792	if (error == secsize)
793		return (0);
794
795	for (i = 1; i < 5; i++) {
796		sprintf(fbuf, "%ss%d", disk, i);
797		fdw = open(fbuf, O_RDWR, 0);
798		if (fdw < 0)
799			continue;
800		error = ioctl(fdw, DIOCSMBR, buf);
801		close(fdw);
802		if (error == 0)
803			return (0);
804	}
805	warnx("Failed to write sector zero");
806	return(EINVAL);
807}
808
809static int
810get_params()
811{
812	int error;
813	u_int u;
814	off_t o;
815
816	error = ioctl(fd, DIOCGFWSECTORS, &u);
817	if (error == 0)
818		sectors = dos_sectors = u;
819	else
820		sectors = dos_sectors = 63;
821
822	error = ioctl(fd, DIOCGFWHEADS, &u);
823	if (error == 0)
824		heads = dos_heads = u;
825	else
826		heads = dos_heads = 255;
827
828	dos_cylsecs = cylsecs = heads * sectors;
829	disksecs = cyls * heads * sectors;
830
831	u = g_sectorsize(fd);
832	if (u <= 0)
833		return (-1);
834
835	o = g_mediasize(fd);
836	if (o < 0)
837		return (-1);
838	disksecs = o / u;
839	cyls = dos_cyls = o / (u * dos_heads * dos_sectors);
840
841	return (disksecs);
842}
843
844static int
845read_s0()
846{
847	int i;
848
849	mboot.bootinst_size = secsize;
850	if (mboot.bootinst != NULL)
851		free(mboot.bootinst);
852	if ((mboot.bootinst = malloc(mboot.bootinst_size)) == NULL) {
853		warnx("unable to allocate buffer to read fdisk "
854		      "partition table");
855		return -1;
856	}
857	if (read_disk(0, mboot.bootinst) == -1) {
858		warnx("can't read fdisk partition table");
859		return -1;
860	}
861	if (le16dec(&mboot.bootinst[DOSMAGICOFFSET]) != DOSMAGIC) {
862		warnx("invalid fdisk partition table found");
863		/* So should we initialize things */
864		return -1;
865	}
866	for (i = 0; i < NDOSPART; i++)
867		dos_partition_dec(
868		    &mboot.bootinst[DOSPARTOFF + i * DOSPARTSIZE],
869		    &mboot.parts[i]);
870	return 0;
871}
872
873static int
874write_s0()
875{
876	int	sector, i;
877
878	if (iotest) {
879		print_s0();
880		return 0;
881	}
882	for(i = 0; i < NDOSPART; i++)
883		dos_partition_enc(&mboot.bootinst[DOSPARTOFF + i * DOSPARTSIZE],
884		    &mboot.parts[i]);
885	le16enc(&mboot.bootinst[DOSMAGICOFFSET], DOSMAGIC);
886	for(sector = 0; sector < mboot.bootinst_size / secsize; sector++)
887		if (write_disk(sector,
888			       &mboot.bootinst[sector * secsize]) == -1) {
889			warn("can't write fdisk partition table");
890			return -1;
891		}
892	return(0);
893}
894
895
896static int
897ok(const char *str)
898{
899	printf("%s [n] ", str);
900	fflush(stdout);
901	if (fgets(lbuf, LBUF, stdin) == NULL)
902		exit(1);
903	lbuf[strlen(lbuf)-1] = 0;
904
905	if (*lbuf &&
906		(!strcmp(lbuf, "yes") || !strcmp(lbuf, "YES") ||
907		 !strcmp(lbuf, "y") || !strcmp(lbuf, "Y")))
908		return 1;
909	else
910		return 0;
911}
912
913static int
914decimal(const char *str, int *num, int deflt)
915{
916	int acc = 0, c;
917	char *cp;
918
919	while (1) {
920		printf("Supply a decimal value for \"%s\" [%d] ", str, deflt);
921		fflush(stdout);
922		if (fgets(lbuf, LBUF, stdin) == NULL)
923			exit(1);
924		lbuf[strlen(lbuf)-1] = 0;
925
926		if (!*lbuf)
927			return 0;
928
929		cp = lbuf;
930		while ((c = *cp) && (c == ' ' || c == '\t')) cp++;
931		if (!c)
932			return 0;
933		while ((c = *cp++)) {
934			if (c <= '9' && c >= '0')
935				acc = acc * 10 + c - '0';
936			else
937				break;
938		}
939		if (c == ' ' || c == '\t')
940			while ((c = *cp) && (c == ' ' || c == '\t')) cp++;
941		if (!c) {
942			*num = acc;
943			return 1;
944		} else
945			printf("%s is an invalid decimal number.  Try again.\n",
946				lbuf);
947	}
948
949}
950
951
952static void
953parse_config_line(char *line, CMD *command)
954{
955    char	*cp, *end;
956
957    cp = line;
958    while (1) {
959	memset(command, 0, sizeof(*command));
960
961	while (isspace(*cp)) ++cp;
962	if (*cp == '\0' || *cp == '#')
963	    break;
964	command->cmd = *cp++;
965
966	/*
967	 * Parse args
968	 */
969	    while (1) {
970	    while (isspace(*cp)) ++cp;
971	    if (*cp == '#')
972		break;		/* found comment */
973	    if (isalpha(*cp))
974		command->args[command->n_args].argtype = *cp++;
975	    if (!isdigit(*cp))
976		break;		/* assume end of line */
977	    end = NULL;
978	    command->args[command->n_args].arg_val = strtol(cp, &end, 0);
979	    if (cp == end)
980		break;		/* couldn't parse number */
981	    cp = end;
982	    command->n_args++;
983	}
984	break;
985    }
986}
987
988
989static int
990process_geometry(CMD *command)
991{
992    int		status = 1, i;
993
994    while (1) {
995	geom_processed = 1;
996	    if (part_processed) {
997	    warnx(
998	"ERROR line %d: the geometry specification line must occur before\n\
999    all partition specifications",
1000		    current_line_number);
1001	    status = 0;
1002	    break;
1003	}
1004	    if (command->n_args != 3) {
1005	    warnx("ERROR line %d: incorrect number of geometry args",
1006		    current_line_number);
1007	    status = 0;
1008	    break;
1009	}
1010	    dos_cyls = 0;
1011	    dos_heads = 0;
1012	    dos_sectors = 0;
1013	    for (i = 0; i < 3; ++i) {
1014		    switch (command->args[i].argtype) {
1015	    case 'c':
1016		dos_cyls = command->args[i].arg_val;
1017		break;
1018	    case 'h':
1019		dos_heads = command->args[i].arg_val;
1020		break;
1021	    case 's':
1022		dos_sectors = command->args[i].arg_val;
1023		break;
1024	    default:
1025		warnx(
1026		"ERROR line %d: unknown geometry arg type: '%c' (0x%02x)",
1027			current_line_number, command->args[i].argtype,
1028			command->args[i].argtype);
1029		status = 0;
1030		break;
1031	    }
1032	}
1033	if (status == 0)
1034	    break;
1035
1036	dos_cylsecs = dos_heads * dos_sectors;
1037
1038	/*
1039	 * Do sanity checks on parameter values
1040	 */
1041	    if (dos_cyls == 0) {
1042	    warnx("ERROR line %d: number of cylinders not specified",
1043		    current_line_number);
1044	    status = 0;
1045	}
1046	    if (dos_cyls > 1024) {
1047	    warnx(
1048	"WARNING line %d: number of cylinders (%d) may be out-of-range\n\
1049    (must be within 1-1024 for normal BIOS operation, unless the entire disk\n\
1050    is dedicated to FreeBSD)",
1051		    current_line_number, dos_cyls);
1052	}
1053
1054	    if (dos_heads == 0) {
1055	    warnx("ERROR line %d: number of heads not specified",
1056		    current_line_number);
1057	    status = 0;
1058	    } else if (dos_heads > 256) {
1059	    warnx("ERROR line %d: number of heads must be within (1-256)",
1060		    current_line_number);
1061	    status = 0;
1062	}
1063
1064	    if (dos_sectors == 0) {
1065	    warnx("ERROR line %d: number of sectors not specified",
1066		    current_line_number);
1067	    status = 0;
1068	    } else if (dos_sectors > 63) {
1069	    warnx("ERROR line %d: number of sectors must be within (1-63)",
1070		    current_line_number);
1071	    status = 0;
1072	}
1073
1074	break;
1075    }
1076    return (status);
1077}
1078
1079
1080static int
1081process_partition(CMD *command)
1082{
1083    int				status = 0, partition;
1084    u_int32_t			prev_head_boundary, prev_cyl_boundary;
1085    u_int32_t			adj_size, max_end;
1086    struct dos_partition	*partp;
1087
1088	while (1) {
1089	part_processed = 1;
1090		if (command->n_args != 4) {
1091	    warnx("ERROR line %d: incorrect number of partition args",
1092		    current_line_number);
1093	    break;
1094	}
1095	partition = command->args[0].arg_val;
1096		if (partition < 1 || partition > 4) {
1097	    warnx("ERROR line %d: invalid partition number %d",
1098		    current_line_number, partition);
1099	    break;
1100	}
1101	partp = &mboot.parts[partition - 1];
1102	bzero(partp, sizeof (*partp));
1103	partp->dp_typ = command->args[1].arg_val;
1104	partp->dp_start = command->args[2].arg_val;
1105	partp->dp_size = command->args[3].arg_val;
1106	max_end = partp->dp_start + partp->dp_size;
1107
1108	if (partp->dp_typ == 0) {
1109	    /*
1110	     * Get out, the partition is marked as unused.
1111	     */
1112	    /*
1113	     * Insure that it's unused.
1114	     */
1115	    bzero(partp, sizeof(*partp));
1116	    status = 1;
1117	    break;
1118	}
1119
1120	/*
1121	 * Adjust start upwards, if necessary, to fall on a head boundary.
1122	 */
1123		if (partp->dp_start % dos_sectors != 0) {
1124	    prev_head_boundary = partp->dp_start / dos_sectors * dos_sectors;
1125	    if (max_end < dos_sectors ||
1126			    prev_head_boundary > max_end - dos_sectors) {
1127		/*
1128		 * Can't go past end of partition
1129		 */
1130		warnx(
1131	"ERROR line %d: unable to adjust start of partition %d to fall on\n\
1132    a head boundary",
1133			current_line_number, partition);
1134		break;
1135	    }
1136	    warnx(
1137	"WARNING: adjusting start offset of partition %d\n\
1138    from %u to %u, to fall on a head boundary",
1139		    partition, (u_int)partp->dp_start,
1140		    (u_int)(prev_head_boundary + dos_sectors));
1141	    partp->dp_start = prev_head_boundary + dos_sectors;
1142	}
1143
1144	/*
1145	 * Adjust size downwards, if necessary, to fall on a cylinder
1146	 * boundary.
1147	 */
1148	prev_cyl_boundary =
1149	    ((partp->dp_start + partp->dp_size) / dos_cylsecs) * dos_cylsecs;
1150	if (prev_cyl_boundary > partp->dp_start)
1151	    adj_size = prev_cyl_boundary - partp->dp_start;
1152		else {
1153	    warnx(
1154	"ERROR: could not adjust partition to start on a head boundary\n\
1155    and end on a cylinder boundary.");
1156	    return (0);
1157	}
1158		if (adj_size != partp->dp_size) {
1159	    warnx(
1160	"WARNING: adjusting size of partition %d from %u to %u\n\
1161    to end on a cylinder boundary",
1162		    partition, (u_int)partp->dp_size, (u_int)adj_size);
1163	    partp->dp_size = adj_size;
1164	}
1165		if (partp->dp_size == 0) {
1166	    warnx("ERROR line %d: size of partition %d is zero",
1167		    current_line_number, partition);
1168	    break;
1169	}
1170
1171	dos(partp);
1172	status = 1;
1173	break;
1174    }
1175    return (status);
1176}
1177
1178
1179static int
1180process_active(CMD *command)
1181{
1182    int				status = 0, partition, i;
1183    struct dos_partition	*partp;
1184
1185	while (1) {
1186	active_processed = 1;
1187		if (command->n_args != 1) {
1188	    warnx("ERROR line %d: incorrect number of active args",
1189		    current_line_number);
1190	    status = 0;
1191	    break;
1192	}
1193	partition = command->args[0].arg_val;
1194		if (partition < 1 || partition > 4) {
1195	    warnx("ERROR line %d: invalid partition number %d",
1196		    current_line_number, partition);
1197	    break;
1198	}
1199	/*
1200	 * Reset active partition
1201	 */
1202	partp = mboot.parts;
1203	for (i = 0; i < NDOSPART; i++)
1204	    partp[i].dp_flag = 0;
1205	partp[partition-1].dp_flag = ACTIVE;
1206
1207	status = 1;
1208	break;
1209    }
1210    return (status);
1211}
1212
1213
1214static int
1215process_line(char *line)
1216{
1217    CMD		command;
1218    int		status = 1;
1219
1220	while (1) {
1221	parse_config_line(line, &command);
1222		switch (command.cmd) {
1223	case 0:
1224	    /*
1225	     * Comment or blank line
1226	     */
1227	    break;
1228	case 'g':
1229	    /*
1230	     * Set geometry
1231	     */
1232	    status = process_geometry(&command);
1233	    break;
1234	case 'p':
1235	    status = process_partition(&command);
1236	    break;
1237	case 'a':
1238	    status = process_active(&command);
1239	    break;
1240	default:
1241	    status = 0;
1242	    break;
1243	}
1244	break;
1245    }
1246    return (status);
1247}
1248
1249
1250static int
1251read_config(char *config_file)
1252{
1253    FILE	*fp = NULL;
1254    int		status = 1;
1255    char	buf[1010];
1256
1257	while (1) {
1258		if (strcmp(config_file, "-") != 0) {
1259	    /*
1260	     * We're not reading from stdin
1261	     */
1262			if ((fp = fopen(config_file, "r")) == NULL) {
1263		status = 0;
1264		break;
1265	    }
1266		} else {
1267	    fp = stdin;
1268	}
1269	current_line_number = 0;
1270		while (!feof(fp)) {
1271	    if (fgets(buf, sizeof(buf), fp) == NULL)
1272		break;
1273	    ++current_line_number;
1274	    status = process_line(buf);
1275	    if (status == 0)
1276		break;
1277	    }
1278	break;
1279    }
1280	if (fp) {
1281	/*
1282	 * It doesn't matter if we're reading from stdin, as we've reached EOF
1283	 */
1284	fclose(fp);
1285    }
1286    return (status);
1287}
1288
1289
1290static void
1291reset_boot(void)
1292{
1293    int				i;
1294    struct dos_partition	*partp;
1295
1296    init_boot();
1297    for (i = 0; i < 4; ++i) {
1298	partp = &mboot.parts[i];
1299	bzero(partp, sizeof(*partp));
1300    }
1301}
1302
1303static int
1304sanitize_partition(struct dos_partition *partp)
1305{
1306    u_int32_t			prev_head_boundary, prev_cyl_boundary;
1307    u_int32_t			max_end, size, start;
1308
1309    start = partp->dp_start;
1310    size = partp->dp_size;
1311    max_end = start + size;
1312    /* Only allow a zero size if the partition is being marked unused. */
1313    if (size == 0) {
1314	if (start == 0 && partp->dp_typ == 0)
1315	    return (1);
1316	warnx("ERROR: size of partition is zero");
1317	return (0);
1318    }
1319    /* Return if no adjustment is necessary. */
1320    if (start % dos_sectors == 0 && (start + size) % dos_sectors == 0)
1321	return (1);
1322
1323    if (start == 0) {
1324	    warnx("WARNING: partition overlaps with partition table");
1325	    if (ok("Correct this automatically?"))
1326		    start = dos_sectors;
1327    }
1328    if (start % dos_sectors != 0)
1329	warnx("WARNING: partition does not start on a head boundary");
1330    if ((start  +size) % dos_sectors != 0)
1331	warnx("WARNING: partition does not end on a cylinder boundary");
1332    warnx("WARNING: this may confuse the BIOS or some operating systems");
1333    if (!ok("Correct this automatically?"))
1334	return (1);
1335
1336    /*
1337     * Adjust start upwards, if necessary, to fall on a head boundary.
1338     */
1339    if (start % dos_sectors != 0) {
1340	prev_head_boundary = start / dos_sectors * dos_sectors;
1341	if (max_end < dos_sectors ||
1342	    prev_head_boundary >= max_end - dos_sectors) {
1343	    /*
1344	     * Can't go past end of partition
1345	     */
1346	    warnx(
1347    "ERROR: unable to adjust start of partition to fall on a head boundary");
1348	    return (0);
1349        }
1350	start = prev_head_boundary + dos_sectors;
1351    }
1352
1353    /*
1354     * Adjust size downwards, if necessary, to fall on a cylinder
1355     * boundary.
1356     */
1357    prev_cyl_boundary = ((start + size) / dos_cylsecs) * dos_cylsecs;
1358    if (prev_cyl_boundary > start)
1359	size = prev_cyl_boundary - start;
1360    else {
1361	warnx("ERROR: could not adjust partition to start on a head boundary\n\
1362    and end on a cylinder boundary.");
1363	return (0);
1364    }
1365
1366    /* Finally, commit any changes to partp and return. */
1367    if (start != partp->dp_start) {
1368	warnx("WARNING: adjusting start offset of partition to %u",
1369	    (u_int)start);
1370	partp->dp_start = start;
1371    }
1372    if (size != partp->dp_size) {
1373	warnx("WARNING: adjusting size of partition to %u", (u_int)size);
1374	partp->dp_size = size;
1375    }
1376
1377    return (1);
1378}
1379
1380/*
1381 * Try figuring out the root device's canonical disk name.
1382 * The following choices are considered:
1383 *   /dev/ad0s1a     => /dev/ad0
1384 *   /dev/da0a       => /dev/da0
1385 *   /dev/vinum/root => /dev/vinum/root
1386 */
1387static char *
1388get_rootdisk(void)
1389{
1390	struct statfs rootfs;
1391	regex_t re;
1392#define NMATCHES 2
1393	regmatch_t rm[NMATCHES];
1394	char *s;
1395	int rv;
1396
1397	if (statfs("/", &rootfs) == -1)
1398		err(1, "statfs(\"/\")");
1399
1400	if ((rv = regcomp(&re, "^(/dev/[a-z/]+[0-9]+)([sp][0-9]+)?[a-h]?$",
1401		    REG_EXTENDED)) != 0)
1402		errx(1, "regcomp() failed (%d)", rv);
1403	if ((rv = regexec(&re, rootfs.f_mntfromname, NMATCHES, rm, 0)) != 0)
1404		errx(1,
1405"mounted root fs resource doesn't match expectations (regexec returned %d)",
1406		    rv);
1407	if ((s = malloc(rm[1].rm_eo - rm[1].rm_so + 1)) == NULL)
1408		errx(1, "out of memory");
1409	memcpy(s, rootfs.f_mntfromname + rm[1].rm_so,
1410	    rm[1].rm_eo - rm[1].rm_so);
1411	s[rm[1].rm_eo - rm[1].rm_so] = 0;
1412
1413	return s;
1414}
1415