1/*	$NetBSD: newfs_msdos.c,v 1.35 2011/03/05 13:47:43 pooka Exp $	*/
2
3/*
4 * Copyright (c) 1998 Robert Nordier
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in
14 *    the documentation and/or other materials provided with the
15 *    distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
18 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
23 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
25 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
26 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
27 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31#ifndef lint
32#if 0
33static const char rcsid[] =
34  "$FreeBSD: src/sbin/newfs_msdos/newfs_msdos.c,v 1.15 2000/10/10 01:49:37 wollman Exp $";
35#else
36__RCSID("$NetBSD: newfs_msdos.c,v 1.35 2011/03/05 13:47:43 pooka Exp $");
37#endif
38#endif /* not lint */
39
40#include <sys/types.h>
41#include <sys/param.h>
42#include <sys/mount.h>
43#include <sys/stat.h>
44#include <sys/time.h>
45#include <sys/disk.h>
46
47#include <ctype.h>
48#include <err.h>
49#include <errno.h>
50#include <fcntl.h>
51#include <paths.h>
52#include <stdio.h>
53#include <stdlib.h>
54#include <string.h>
55#include <time.h>
56#include <unistd.h>
57#include <signal.h>
58
59#include <util.h>
60#include <disktab.h>
61
62#include "partutil.h"
63
64#define MAXU16	  0xffff	/* maximum unsigned 16-bit quantity */
65#define BPN	  4		/* bits per nibble */
66#define NPB	  2		/* nibbles per byte */
67
68#define DOSMAGIC  0xaa55	/* DOS magic number */
69#define MINBPS	  512		/* minimum bytes per sector */
70#define MAXSPC	  128		/* maximum sectors per cluster */
71#define MAXNFT	  16		/* maximum number of FATs */
72#define DEFBLK	  4096		/* default block size */
73#define DEFBLK16  2048		/* default block size FAT16 */
74#define DEFRDE	  512		/* default root directory entries */
75#define RESFTE	  2		/* reserved FAT entries */
76#define MINCLS12  1		/* minimum FAT12 clusters */
77#define MINCLS16  0x1000	/* minimum FAT16 clusters */
78#define MINCLS32  2		/* minimum FAT32 clusters */
79#define MAXCLS12  0xfed 	/* maximum FAT12 clusters */
80#define MAXCLS16  0xfff5	/* maximum FAT16 clusters */
81#define MAXCLS32  0xffffff5	/* maximum FAT32 clusters */
82
83#define mincls(fat)  ((fat) == 12 ? MINCLS12 :	\
84		      (fat) == 16 ? MINCLS16 :	\
85				    MINCLS32)
86
87#define maxcls(fat)  ((fat) == 12 ? MAXCLS12 :	\
88		      (fat) == 16 ? MAXCLS16 :	\
89				    MAXCLS32)
90
91#define mk1(p, x)				\
92    (p) = (u_int8_t)(x)
93
94#define mk2(p, x)				\
95    (p)[0] = (u_int8_t)(x),			\
96    (p)[1] = (u_int8_t)((x) >> 010)
97
98#define mk4(p, x)				\
99    (p)[0] = (u_int8_t)(x),			\
100    (p)[1] = (u_int8_t)((x) >> 010),		\
101    (p)[2] = (u_int8_t)((x) >> 020),		\
102    (p)[3] = (u_int8_t)((x) >> 030)
103
104#define argto1(arg, lo, msg)  argtou(arg, lo, 0xff, msg)
105#define argto2(arg, lo, msg)  argtou(arg, lo, 0xffff, msg)
106#define argto4(arg, lo, msg)  argtou(arg, lo, 0xffffffff, msg)
107#define argtox(arg, lo, msg)  argtou(arg, lo, UINT_MAX, msg)
108
109struct bs {
110    u_int8_t jmp[3];		/* bootstrap entry point */
111    u_int8_t oem[8];		/* OEM name and version */
112};
113
114struct bsbpb {
115    u_int8_t bps[2];		/* bytes per sector */
116    u_int8_t spc;		/* sectors per cluster */
117    u_int8_t res[2];		/* reserved sectors */
118    u_int8_t nft;		/* number of FATs */
119    u_int8_t rde[2];		/* root directory entries */
120    u_int8_t sec[2];		/* total sectors */
121    u_int8_t mid;		/* media descriptor */
122    u_int8_t spf[2];		/* sectors per FAT */
123    u_int8_t spt[2];		/* sectors per track */
124    u_int8_t hds[2];		/* drive heads */
125    u_int8_t hid[4];		/* hidden sectors */
126    u_int8_t bsec[4];		/* big total sectors */
127};
128
129struct bsxbpb {
130    u_int8_t bspf[4];		/* big sectors per FAT */
131    u_int8_t xflg[2];		/* FAT control flags */
132    u_int8_t vers[2];		/* file system version */
133    u_int8_t rdcl[4];		/* root directory start cluster */
134    u_int8_t infs[2];		/* file system info sector */
135    u_int8_t bkbs[2];		/* backup boot sector */
136    u_int8_t rsvd[12];		/* reserved */
137};
138
139struct bsx {
140    u_int8_t drv;		/* drive number */
141    u_int8_t rsvd;		/* reserved */
142    u_int8_t sig;		/* extended boot signature */
143    u_int8_t volid[4];		/* volume ID number */
144    u_int8_t label[11]; 	/* volume label */
145    u_int8_t type[8];		/* file system type */
146};
147
148struct de {
149    u_int8_t namext[11];	/* name and extension */
150    u_int8_t attr;		/* attributes */
151    u_int8_t rsvd[10];		/* reserved */
152    u_int8_t time[2];		/* creation time */
153    u_int8_t date[2];		/* creation date */
154    u_int8_t clus[2];		/* starting cluster */
155    u_int8_t size[4];		/* size */
156};
157
158struct bpb {
159    u_int bps;			/* bytes per sector */
160    u_int spc;			/* sectors per cluster */
161    u_int res;			/* reserved sectors */
162    u_int nft;			/* number of FATs */
163    u_int rde;			/* root directory entries */
164    u_int sec;			/* total sectors */
165    u_int mid;			/* media descriptor */
166    u_int spf;			/* sectors per FAT */
167    u_int spt;			/* sectors per track */
168    u_int hds;			/* drive heads */
169    u_int hid;			/* hidden sectors */
170    u_int bsec; 		/* big total sectors */
171    u_int bspf; 		/* big sectors per FAT */
172    u_int rdcl; 		/* root directory start cluster */
173    u_int infs; 		/* file system info sector */
174    u_int bkbs; 		/* backup boot sector */
175};
176
177#define INIT(a, b, c, d, e, f, g, h, i, j) \
178    { .bps = a, .spc = b, .res = c, .nft = d, .rde = e, \
179      .sec = f, .mid = g, .spf = h, .spt = i, .hds = j, }
180static struct {
181    const char *name;
182    struct bpb bpb;
183} stdfmt[] = {
184    {"160",  INIT(512, 1, 1, 2,  64,  320, 0xfe, 1,  8, 1)},
185    {"180",  INIT(512, 1, 1, 2,  64,  360, 0xfc, 2,  9, 1)},
186    {"320",  INIT(512, 2, 1, 2, 112,  640, 0xff, 1,  8, 2)},
187    {"360",  INIT(512, 2, 1, 2, 112,  720, 0xfd, 2,  9, 2)},
188    {"640",  INIT(512, 2, 1, 2, 112, 1280, 0xfb, 2,  8, 2)},
189    {"720",  INIT(512, 2, 1, 2, 112, 1440, 0xf9, 3,  9, 2)},
190    {"1200", INIT(512, 1, 1, 2, 224, 2400, 0xf9, 7, 15, 2)},
191    {"1232", INIT(1024,1, 1, 2, 192, 1232, 0xfe, 2,  8, 2)},
192    {"1440", INIT(512, 1, 1, 2, 224, 2880, 0xf0, 9, 18, 2)},
193    {"2880", INIT(512, 2, 1, 2, 240, 5760, 0xf0, 9, 36, 2)}
194};
195
196static u_int8_t bootcode[] = {
197    0xfa,			/* cli		    */
198    0x31, 0xc0, 		/* xor	   ax,ax    */
199    0x8e, 0xd0, 		/* mov	   ss,ax    */
200    0xbc, 0x00, 0x7c,		/* mov	   sp,7c00h */
201    0xfb,			/* sti		    */
202    0x8e, 0xd8, 		/* mov	   ds,ax    */
203    0xe8, 0x00, 0x00,		/* call    $ + 3    */
204    0x5e,			/* pop	   si	    */
205    0x83, 0xc6, 0x19,		/* add	   si,+19h  */
206    0xbb, 0x07, 0x00,		/* mov	   bx,0007h */
207    0xfc,			/* cld		    */
208    0xac,			/* lodsb	    */
209    0x84, 0xc0, 		/* test    al,al    */
210    0x74, 0x06, 		/* jz	   $ + 8    */
211    0xb4, 0x0e, 		/* mov	   ah,0eh   */
212    0xcd, 0x10, 		/* int	   10h	    */
213    0xeb, 0xf5, 		/* jmp	   $ - 9    */
214    0x30, 0xe4, 		/* xor	   ah,ah    */
215    0xcd, 0x16, 		/* int	   16h	    */
216    0xcd, 0x19, 		/* int	   19h	    */
217    0x0d, 0x0a,
218    'N', 'o', 'n', '-', 's', 'y', 's', 't',
219    'e', 'm', ' ', 'd', 'i', 's', 'k',
220    0x0d, 0x0a,
221    'P', 'r', 'e', 's', 's', ' ', 'a', 'n',
222    'y', ' ', 'k', 'e', 'y', ' ', 't', 'o',
223    ' ', 'r', 'e', 'b', 'o', 'o', 't',
224    0x0d, 0x0a,
225    0
226};
227
228static int	got_siginfo = 0; /* received a SIGINFO */
229
230static void check_mounted(const char *, mode_t);
231static void getstdfmt(const char *, struct bpb *);
232static void getbpbinfo(int, const char *, const char *, int, struct bpb *, int);
233static void print_bpb(struct bpb *);
234static u_int ckgeom(const char *, u_int, const char *);
235static u_int argtou(const char *, u_int, u_int, const char *);
236static off_t argtooff(const char *, const char *);
237static int oklabel(const char *);
238static void mklabel(u_int8_t *, const char *);
239static void setstr(u_int8_t *, const char *, size_t);
240__dead static void usage(void);
241static void infohandler(int sig);
242
243/*
244 * Construct a FAT12, FAT16, or FAT32 file system.
245 */
246int
247main(int argc, char *argv[])
248{
249    static char opts[] = "@:NB:C:F:I:L:O:S:a:b:c:e:f:h:i:k:m:n:o:r:s:u:";
250    static const char *opt_B, *opt_L, *opt_O, *opt_f;
251    static u_int opt_F, opt_I, opt_S, opt_a, opt_b, opt_c, opt_e;
252    static u_int opt_h, opt_i, opt_k, opt_m, opt_n, opt_o, opt_r;
253    static u_int opt_s, opt_u;
254    static int opt_N;
255    static int Iflag, mflag, oflag;
256    char buf[MAXPATHLEN];
257    struct stat sb;
258    struct timeval tv;
259    struct bpb bpb;
260    struct tm *tm;
261    struct bs *bs;
262    struct bsbpb *bsbpb;
263    struct bsxbpb *bsxbpb;
264    struct bsx *bsx;
265    struct de *de;
266    u_int8_t *img;
267    const char *fname, *dtype, *bname;
268    ssize_t n;
269    time_t now;
270    u_int fat, bss, rds, cls, dir, lsn, x, x1, x2;
271    int ch, fd, fd1;
272    static off_t opt_create=0, opt_ofs=0;
273
274    while ((ch = getopt(argc, argv, opts)) != -1)
275	switch (ch) {
276	case '@':
277	    opt_ofs = argtooff(optarg, "offset");
278	    break;
279	case 'N':
280	    opt_N = 1;
281	    break;
282	case 'B':
283	    opt_B = optarg;
284	    break;
285	case 'C':
286	    opt_create = argtooff(optarg, "create size");
287	    break;
288	case 'F':
289	    if (strcmp(optarg, "12") &&
290		strcmp(optarg, "16") &&
291		strcmp(optarg, "32"))
292		errx(1, "%s: bad FAT type", optarg);
293	    opt_F = atoi(optarg);
294	    break;
295	case 'I':
296	    opt_I = argto4(optarg, 0, "volume ID");
297	    Iflag = 1;
298	    break;
299	case 'L':
300	    if (!oklabel(optarg))
301		errx(1, "%s: bad volume label", optarg);
302	    opt_L = optarg;
303	    break;
304	case 'O':
305	    if (strlen(optarg) > 8)
306		errx(1, "%s: bad OEM string", optarg);
307	    opt_O = optarg;
308	    break;
309	case 'S':
310	    opt_S = argto2(optarg, 1, "bytes/sector");
311	    break;
312	case 'a':
313	    opt_a = argto4(optarg, 1, "sectors/FAT");
314	    break;
315	case 'b':
316	    opt_b = argtox(optarg, 1, "block size");
317	    opt_c = 0;
318	    break;
319	case 'c':
320	    opt_c = argto1(optarg, 1, "sectors/cluster");
321	    opt_b = 0;
322	    break;
323	case 'e':
324	    opt_e = argto2(optarg, 1, "directory entries");
325	    break;
326	case 'f':
327	    opt_f = optarg;
328	    break;
329	case 'h':
330	    opt_h = argto2(optarg, 1, "drive heads");
331	    break;
332	case 'i':
333	    opt_i = argto2(optarg, 1, "info sector");
334	    break;
335	case 'k':
336	    opt_k = argto2(optarg, 1, "backup sector");
337	    break;
338	case 'm':
339	    opt_m = argto1(optarg, 0, "media descriptor");
340	    mflag = 1;
341	    break;
342	case 'n':
343	    opt_n = argto1(optarg, 1, "number of FATs");
344	    break;
345	case 'o':
346	    opt_o = argto4(optarg, 0, "hidden sectors");
347	    oflag = 1;
348	    break;
349	case 'r':
350	    opt_r = argto2(optarg, 1, "reserved sectors");
351	    break;
352	case 's':
353	    opt_s = argto4(optarg, 1, "file system size");
354	    break;
355	case 'u':
356	    opt_u = argto2(optarg, 1, "sectors/track");
357	    break;
358	default:
359	    usage();
360	}
361    argc -= optind;
362    argv += optind;
363    if (argc < 1 || argc > 2)
364	usage();
365    fname = *argv++;
366    if (!strchr(fname, '/') && !opt_create) {
367	snprintf(buf, sizeof(buf), "%sr%s", _PATH_DEV, fname);
368	if (!(fname = strdup(buf)))
369	    err(1, NULL);
370    }
371    dtype = *argv;
372    if (opt_create) {
373	off_t pos;
374
375	if (opt_N)
376	    errx(1, "create (-C) is incompatible with -N");
377	fd = open(fname, O_RDWR | O_CREAT | O_TRUNC, 0644);
378	if (fd == -1)
379	    errx(1, "failed to create %s", fname);
380	pos = lseek(fd, opt_create - 1, SEEK_SET);
381	if (write(fd, "\0", 1) != 1)
382	    err(1, "failed to set file size");
383	pos = lseek(fd, 0, SEEK_SET);
384    } else if ((fd = open(fname, opt_N ? O_RDONLY : O_RDWR)) == -1 ||
385	fstat(fd, &sb))
386	err(1, "%s", fname);
387    if (!opt_N)
388	check_mounted(fname, sb.st_mode);
389    if (!S_ISCHR(sb.st_mode) && !opt_create)
390	warnx("warning, %s is not a character device", fname);
391    if (opt_ofs && opt_ofs != lseek(fd, opt_ofs, SEEK_SET))
392	errx(1, "cannot seek to %jd", (intmax_t)opt_ofs);
393    memset(&bpb, 0, sizeof(bpb));
394    if (opt_f) {
395	getstdfmt(opt_f, &bpb);
396	bpb.bsec = bpb.sec;
397	bpb.sec = 0;
398	bpb.bspf = bpb.spf;
399	bpb.spf = 0;
400    }
401    if (opt_h)
402	bpb.hds = opt_h;
403    if (opt_u)
404	bpb.spt = opt_u;
405    if (opt_S)
406	bpb.bps = opt_S;
407    if (opt_s)
408	bpb.bsec = opt_s;
409    if (oflag)
410	bpb.hid = opt_o;
411    if (!(opt_f || (opt_h && opt_u && opt_S && opt_s && oflag))) {
412	off_t delta;
413	getbpbinfo(fd, fname, dtype, oflag, &bpb, opt_create != 0);
414	bpb.bsec -= (opt_ofs / bpb.bps);
415	delta = bpb.bsec % bpb.spt;
416	if (delta != 0) {
417	    warnx("trim %d sectors to adjust to a multiple of %d",
418		(int)delta, bpb.spt);
419	    bpb.bsec -= delta;
420	}
421	if (bpb.spc == 0) {     /* set defaults */
422	    if (bpb.bsec <= 6000)       /* about 3MB -> 512 bytes */
423		bpb.spc = 1;
424	    else if (bpb.bsec <= (1<<17)) /* 64M -> 4k */
425		bpb.spc = 8;
426	    else if (bpb.bsec <= (1<<19)) /* 256M -> 8k */
427		bpb.spc = 16;
428	    else if (bpb.bsec <= (1<<21)) /* 1G -> 16k */
429		bpb.spc = 32;
430	    else
431		bpb.spc = 64;           /* otherwise 32k */
432	}
433    }
434    if (!powerof2(bpb.bps))
435	errx(1, "bytes/sector (%u) is not a power of 2", bpb.bps);
436    if (bpb.bps < MINBPS)
437	errx(1, "bytes/sector (%u) is too small; minimum is %u",
438	     bpb.bps, MINBPS);
439    if (!(fat = opt_F)) {
440	if (opt_f)
441	    fat = 12;
442	else if (!opt_e && (opt_i || opt_k))
443	    fat = 32;
444    }
445    if ((fat == 32 && opt_e) || (fat != 32 && (opt_i || opt_k)))
446	errx(1, "-%c is not a legal FAT%s option",
447	     fat == 32 ? 'e' : opt_i ? 'i' : 'k',
448	     fat == 32 ? "32" : "12/16");
449    if (opt_f && fat == 32)
450	bpb.rde = 0;
451    if (opt_b) {
452	if (!powerof2(opt_b))
453	    errx(1, "block size (%u) is not a power of 2", opt_b);
454	if (opt_b < bpb.bps)
455	    errx(1, "block size (%u) is too small; minimum is %u",
456		 opt_b, bpb.bps);
457	if (opt_b > bpb.bps * MAXSPC)
458	    errx(1, "block size (%u) is too large; maximum is %u",
459		 opt_b, bpb.bps * MAXSPC);
460	bpb.spc = opt_b / bpb.bps;
461    }
462    if (opt_c) {
463	if (!powerof2(opt_c))
464	    errx(1, "sectors/cluster (%u) is not a power of 2", opt_c);
465	bpb.spc = opt_c;
466    }
467    if (opt_r)
468	bpb.res = opt_r;
469    if (opt_n) {
470	if (opt_n > MAXNFT)
471	    errx(1, "number of FATs (%u) is too large; maximum is %u",
472		 opt_n, MAXNFT);
473	bpb.nft = opt_n;
474    }
475    if (opt_e)
476	bpb.rde = opt_e;
477    if (mflag) {
478	if (opt_m < 0xf0)
479	    errx(1, "illegal media descriptor (%#x)", opt_m);
480	bpb.mid = opt_m;
481    }
482    if (opt_a)
483	bpb.bspf = opt_a;
484    if (opt_i)
485	bpb.infs = opt_i;
486    if (opt_k)
487	bpb.bkbs = opt_k;
488    bss = 1;
489    bname = NULL;
490    fd1 = -1;
491    if (opt_B) {
492	bname = opt_B;
493	if (!strchr(bname, '/')) {
494	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
495	    if (!(bname = strdup(buf)))
496		err(1, NULL);
497	}
498	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb))
499	    err(1, "%s", bname);
500	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bps ||
501	    sb.st_size < bpb.bps || sb.st_size > bpb.bps * MAXU16)
502	    errx(1, "%s: inappropriate file type or format", bname);
503	bss = sb.st_size / bpb.bps;
504    }
505    if (!bpb.nft)
506	bpb.nft = 2;
507    if (!fat) {
508	if (bpb.bsec < (bpb.res ? bpb.res : bss) +
509	    howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
510		    ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
511	    bpb.nft +
512	    howmany(bpb.rde ? bpb.rde : DEFRDE,
513		    bpb.bps / sizeof(struct de)) +
514	    (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
515	    (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
516	    fat = 12;
517	else if (bpb.rde || bpb.bsec <
518		 (bpb.res ? bpb.res : bss) +
519		 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
520		 howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
521		 (MAXCLS16 + 1) *
522		 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
523	    fat = 16;
524	else
525	    fat = 32;
526    }
527    x = bss;
528    if (fat == 32) {
529	if (!bpb.infs) {
530	    if (x == MAXU16 || x == bpb.bkbs)
531		errx(1, "no room for info sector");
532	    bpb.infs = x;
533	}
534	if (bpb.infs != MAXU16 && x <= bpb.infs)
535	    x = bpb.infs + 1;
536	if (!bpb.bkbs) {
537	    if (x == MAXU16)
538		errx(1, "no room for backup sector");
539	    bpb.bkbs = x;
540	} else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs)
541	    errx(1, "backup sector would overwrite info sector");
542	if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
543	    x = bpb.bkbs + 1;
544    }
545    if (!bpb.res)
546	bpb.res = fat == 32 ? MAX(x, MAX(16384 / bpb.bps, 4)) : x;
547    else if (bpb.res < x)
548	errx(1, "too few reserved sectors (need %d have %d)", x, bpb.res);
549    if (fat != 32 && !bpb.rde)
550	bpb.rde = DEFRDE;
551    rds = howmany(bpb.rde, bpb.bps / sizeof(struct de));
552    if (!bpb.spc)
553	for (bpb.spc = howmany(fat == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
554	     bpb.spc < MAXSPC &&
555	     bpb.res +
556	     howmany((RESFTE + maxcls(fat)) * (fat / BPN),
557		     bpb.bps * NPB) * bpb.nft +
558	     rds +
559	     (u_int64_t)(maxcls(fat) + 1) * bpb.spc <= bpb.bsec;
560	     bpb.spc <<= 1);
561    if (fat != 32 && bpb.bspf > MAXU16)
562	errx(1, "too many sectors/FAT for FAT12/16");
563    x1 = bpb.res + rds;
564    x = bpb.bspf ? bpb.bspf : 1;
565    if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec)
566	errx(1, "meta data exceeds file system size");
567    x1 += x * bpb.nft;
568    x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
569	(bpb.spc * bpb.bps * NPB + fat / BPN * bpb.nft);
570    x2 = howmany((RESFTE + MIN(x, maxcls(fat))) * (fat / BPN),
571		 bpb.bps * NPB);
572    if (!bpb.bspf) {
573	bpb.bspf = x2;
574	x1 += (bpb.bspf - 1) * bpb.nft;
575    }
576    cls = (bpb.bsec - x1) / bpb.spc;
577    x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (fat / BPN) - RESFTE;
578    if (cls > x)
579	cls = x;
580    if (bpb.bspf < x2)
581	warnx("warning: sectors/FAT limits file system to %u clusters",
582	      cls);
583    if (cls < mincls(fat))
584	errx(1, "%u clusters too few clusters for FAT%u, need %u", cls, fat,
585	    mincls(fat));
586    if (cls > maxcls(fat)) {
587	cls = maxcls(fat);
588	bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
589	warnx("warning: FAT type limits file system to %u sectors",
590	      bpb.bsec);
591    }
592    printf("%s: %u sector%s in %u FAT%u cluster%s "
593	   "(%u bytes/cluster)\n", fname, cls * bpb.spc,
594	   cls * bpb.spc == 1 ? "" : "s", cls, fat,
595	   cls == 1 ? "" : "s", bpb.bps * bpb.spc);
596    if (!bpb.mid)
597	bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
598    if (fat == 32)
599	bpb.rdcl = RESFTE;
600    if (bpb.hid + bpb.bsec <= MAXU16) {
601	bpb.sec = bpb.bsec;
602	bpb.bsec = 0;
603    }
604    if (fat != 32) {
605	bpb.spf = bpb.bspf;
606	bpb.bspf = 0;
607    }
608    ch = 0;
609    if (fat == 12)
610	ch = 1;			/* 001 Primary DOS with 12 bit FAT */
611    else if (fat == 16) {
612	if (bpb.bsec == 0)
613	    ch = 4;		/* 004 Primary DOS with 16 bit FAT <32M */
614	else
615	    ch = 6;		/* 006 Primary 'big' DOS, 16-bit FAT (> 32MB) */
616				/*
617				 * XXX: what about:
618				 * 014 DOS (16-bit FAT) - LBA
619				 *  ?
620				 */
621    } else if (fat == 32) {
622	ch = 11;		/* 011 Primary DOS with 32 bit FAT */
623				/*
624				 * XXX: what about:
625				 * 012 Primary DOS with 32 bit FAT - LBA
626				 *  ?
627				 */
628    }
629    if (ch != 0)
630	printf("MBR type: %d\n", ch);
631    print_bpb(&bpb);
632    if (!opt_N) {
633	gettimeofday(&tv, NULL);
634	now = tv.tv_sec;
635	tm = localtime(&now);
636	if (!(img = malloc(bpb.bps)))
637	    err(1, NULL);
638	dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;
639	signal(SIGINFO, infohandler);
640	for (lsn = 0; lsn < dir + (fat == 32 ? bpb.spc : rds); lsn++) {
641	    if (got_siginfo) {
642		fprintf(stderr,"%s: writing sector %u of %u (%u%%)\n",
643		    fname,lsn,(dir + (fat == 32 ? bpb.spc : rds)),
644		    (lsn*100)/(dir + (fat == 32 ? bpb.spc : rds)));
645		got_siginfo = 0;
646	    }
647	    x = lsn;
648	    if (opt_B &&
649		fat == 32 && bpb.bkbs != MAXU16 &&
650		bss <= bpb.bkbs && x >= bpb.bkbs) {
651		x -= bpb.bkbs;
652		if (!x && lseek(fd1, opt_ofs, SEEK_SET))
653		    err(1, "%s", bname);
654	    }
655	    if (opt_B && x < bss) {
656		if ((n = read(fd1, img, bpb.bps)) == -1)
657		    err(1, "%s", bname);
658		if ((size_t)n != bpb.bps)
659		    errx(1, "%s: can't read sector %u", bname, x);
660	    } else
661		memset(img, 0, bpb.bps);
662	    if (!lsn ||
663	      (fat == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
664		x1 = sizeof(struct bs);
665		bsbpb = (struct bsbpb *)(img + x1);
666		mk2(bsbpb->bps, bpb.bps);
667		mk1(bsbpb->spc, bpb.spc);
668		mk2(bsbpb->res, bpb.res);
669		mk1(bsbpb->nft, bpb.nft);
670		mk2(bsbpb->rde, bpb.rde);
671		mk2(bsbpb->sec, bpb.sec);
672		mk1(bsbpb->mid, bpb.mid);
673		mk2(bsbpb->spf, bpb.spf);
674		mk2(bsbpb->spt, bpb.spt);
675		mk2(bsbpb->hds, bpb.hds);
676		mk4(bsbpb->hid, bpb.hid);
677		mk4(bsbpb->bsec, bpb.bsec);
678		x1 += sizeof(struct bsbpb);
679		if (fat == 32) {
680		    bsxbpb = (struct bsxbpb *)(img + x1);
681		    mk4(bsxbpb->bspf, bpb.bspf);
682		    mk2(bsxbpb->xflg, 0);
683		    mk2(bsxbpb->vers, 0);
684		    mk4(bsxbpb->rdcl, bpb.rdcl);
685		    mk2(bsxbpb->infs, bpb.infs);
686		    mk2(bsxbpb->bkbs, bpb.bkbs);
687		    x1 += sizeof(struct bsxbpb);
688		}
689		bsx = (struct bsx *)(img + x1);
690		mk1(bsx->sig, 0x29);
691		if (Iflag)
692		    x = opt_I;
693		else
694		    x = (((u_int)(1 + tm->tm_mon) << 8 |
695			  (u_int)tm->tm_mday) +
696			 ((u_int)tm->tm_sec << 8 |
697			  (u_int)(tv.tv_usec / 10))) << 16 |
698			((u_int)(1900 + tm->tm_year) +
699			 ((u_int)tm->tm_hour << 8 |
700			  (u_int)tm->tm_min));
701		mk4(bsx->volid, x);
702		mklabel(bsx->label, opt_L ? opt_L : "NO_NAME");
703		snprintf(buf, sizeof(buf), "FAT%u", fat);
704		setstr(bsx->type, buf, sizeof(bsx->type));
705		if (!opt_B) {
706		    x1 += sizeof(struct bsx);
707		    bs = (struct bs *)img;
708		    mk1(bs->jmp[0], 0xeb);
709		    mk1(bs->jmp[1], x1 - 2);
710		    mk1(bs->jmp[2], 0x90);
711		    setstr(bs->oem, opt_O ? opt_O : "NetBSD",
712			   sizeof(bs->oem));
713		    memcpy(img + x1, bootcode, sizeof(bootcode));
714		    mk2(img + MINBPS - 2, DOSMAGIC);
715		}
716	    } else if (fat == 32 && bpb.infs != MAXU16 &&
717		       (lsn == bpb.infs ||
718			(bpb.bkbs != MAXU16 &&
719			 lsn == bpb.bkbs + bpb.infs))) {
720		mk4(img, 0x41615252);
721		mk4(img + MINBPS - 28, 0x61417272);
722		mk4(img + MINBPS - 24, 0xffffffff);
723		mk4(img + MINBPS - 20, bpb.rdcl);
724		mk2(img + MINBPS - 2, DOSMAGIC);
725	    } else if (lsn >= bpb.res && lsn < dir &&
726		       !((lsn - bpb.res) %
727			 (bpb.spf ? bpb.spf : bpb.bspf))) {
728		mk1(img[0], bpb.mid);
729		for (x = 1; x < fat * (fat == 32 ? 3 : 2) / 8; x++)
730		    mk1(img[x], fat == 32 && x % 4 == 3 ? 0x0f : 0xff);
731	    } else if (lsn == dir && opt_L) {
732		de = (struct de *)img;
733		mklabel(de->namext, opt_L);
734		mk1(de->attr, 050);
735		x = (u_int)tm->tm_hour << 11 |
736		    (u_int)tm->tm_min << 5 |
737		    (u_int)tm->tm_sec >> 1;
738		mk2(de->time, x);
739		x = (u_int)(tm->tm_year - 80) << 9 |
740		    (u_int)(tm->tm_mon + 1) << 5 |
741		    (u_int)tm->tm_mday;
742		mk2(de->date, x);
743	    }
744	    if ((n = write(fd, img, bpb.bps)) == -1)
745		err(1, "%s", fname);
746	    if ((size_t)n != bpb.bps)
747		errx(1, "%s: can't write sector %u", fname, lsn);
748	}
749    }
750    return 0;
751}
752
753/*
754 * Exit with error if file system is mounted.
755 */
756static void
757check_mounted(const char *fname, mode_t mode)
758{
759    struct statvfs *mp;
760    const char *s1, *s2;
761    size_t len;
762    int n, r;
763
764    if (!(n = getmntinfo(&mp, MNT_NOWAIT)))
765	err(1, "getmntinfo");
766    len = strlen(_PATH_DEV);
767    s1 = fname;
768    if (!strncmp(s1, _PATH_DEV, len))
769	s1 += len;
770    r = S_ISCHR(mode) && s1 != fname && *s1 == 'r';
771    for (; n--; mp++) {
772	s2 = mp->f_mntfromname;
773	if (!strncmp(s2, _PATH_DEV, len))
774	    s2 += len;
775	if ((r && s2 != mp->f_mntfromname && !strcmp(s1 + 1, s2)) ||
776	    !strcmp(s1, s2))
777	    errx(1, "%s is mounted on %s", fname, mp->f_mntonname);
778    }
779}
780
781/*
782 * Get a standard format.
783 */
784static void
785getstdfmt(const char *fmt, struct bpb *bpb)
786{
787    u_int x, i;
788
789    x = sizeof(stdfmt) / sizeof(stdfmt[0]);
790    for (i = 0; i < x && strcmp(fmt, stdfmt[i].name); i++);
791    if (i == x)
792	errx(1, "%s: unknown standard format", fmt);
793    *bpb = stdfmt[i].bpb;
794}
795
796/*
797 * Get disk slice, partition, and geometry information.
798 */
799static void
800getbpbinfo(int fd, const char *fname, const char *dtype, int oflag,
801	    struct bpb *bpb, int create)
802{
803    struct disk_geom geo;
804    struct dkwedge_info dkw;
805    const char *s1, *s2;
806    int part;
807    int maxpartitions;
808
809    part = -1;
810    s1 = fname;
811    if ((s2 = strrchr(s1, '/')))
812	s1 = s2 + 1;
813    for (s2 = s1; *s2 && !isdigit((unsigned char)*s2); s2++);
814    if (!*s2 || s2 == s1)
815	s2 = NULL;
816    else
817	while (isdigit((unsigned char)*++s2));
818    s1 = s2;
819
820    maxpartitions = getmaxpartitions();
821
822    if (s2 && *s2 >= 'a' && *s2 <= 'a' + maxpartitions - 1) {
823	part = *s2++ - 'a';
824    }
825    if (((part != -1) && ((!oflag && part != -1) || !bpb->bsec)) ||
826	!bpb->bps || !bpb->spt || !bpb->hds) {
827	if (create || getdiskinfo(fname, fd, NULL, &geo, &dkw) == -1) {
828	    struct stat st;
829
830	    if (fstat(fd, &st) == -1)
831		errx(1, "Can't get disk size for `%s'", fname);
832	    /* create a fake geometry for a file image */
833	    geo.dg_secsize = 512;
834	    geo.dg_nsectors = 63;
835	    geo.dg_ntracks = 255;
836	    dkw.dkw_size = st.st_size / geo.dg_secsize;
837	}
838	if (!bpb->bps)
839	    bpb->bps = ckgeom(fname, geo.dg_secsize, "bytes/sector");
840
841	if (geo.dg_nsectors > 63) {
842		/*
843		 * The kernel doesn't accept BPB with spt > 63.
844		 * (see sys/fs/msdosfs/msdosfs_vfsops.c:msdosfs_mountfs())
845		 * If values taken from disklabel don't match these
846		 * restrictions, use popular BIOS default values instead.
847		 */
848		geo.dg_nsectors = 63;
849	}
850	if (!bpb->spt)
851	    bpb->spt = ckgeom(fname, geo.dg_nsectors, "sectors/track");
852	if (!bpb->hds)
853	    bpb->hds = ckgeom(fname, geo.dg_ntracks, "drive heads");
854	if (!bpb->bsec)
855	    bpb->bsec = dkw.dkw_size;
856    }
857}
858
859/*
860 * Print out BPB values.
861 */
862static void
863print_bpb(struct bpb *bpb)
864{
865    printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
866	   bpb->nft);
867    if (bpb->rde)
868	printf(" rde=%u", bpb->rde);
869    if (bpb->sec)
870	printf(" sec=%u", bpb->sec);
871    printf(" mid=%#x", bpb->mid);
872    if (bpb->spf)
873	printf(" spf=%u", bpb->spf);
874    printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
875    if (bpb->bsec)
876	printf(" bsec=%u", bpb->bsec);
877    if (!bpb->spf) {
878	printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
879	printf(" infs=");
880	printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
881	printf(" bkbs=");
882	printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
883    }
884    printf("\n");
885}
886
887/*
888 * Check a disk geometry value.
889 */
890static u_int
891ckgeom(const char *fname, u_int val, const char *msg)
892{
893    if (!val)
894	errx(1, "%s: no default %s", fname, msg);
895    if (val > MAXU16)
896	errx(1, "%s: illegal %s", fname, msg);
897    return val;
898}
899
900/*
901 * Convert and check a numeric option argument.
902 */
903static u_int
904argtou(const char *arg, u_int lo, u_int hi, const char *msg)
905{
906    char *s;
907    u_long x;
908
909    errno = 0;
910    x = strtoul(arg, &s, 0);
911    if (errno || !*arg || *s || x < lo || x > hi)
912	errx(1, "%s: bad %s", arg, msg);
913    return x;
914}
915
916/*
917 * Same for off_t, with optional skmgpP suffix
918 */
919static off_t
920argtooff(const char *arg, const char *msg)
921{
922    char *s;
923    off_t x;
924
925    errno = 0;
926    x = strtoll(arg, &s, 0);
927    /* allow at most one extra char */
928    if (errno || x < 0 || (s[0] && s[1]) )
929	errx(1, "%s: bad %s", arg, msg);
930    if (*s) {	/* the extra char is the multiplier */
931	switch (*s) {
932	default:
933	    errx(1, "%s: bad %s", arg, msg);
934	    /* notreached */
935
936	case 's':	/* sector */
937	case 'S':
938	    x <<= 9;	/* times 512 */
939	    break;
940
941	case 'k':	/* kilobyte */
942	case 'K':
943	    x <<= 10;	/* times 1024 */
944	    break;
945
946	case 'm':	/* megabyte */
947	case 'M':
948	    x <<= 20;	/* times 1024*1024 */
949	    break;
950
951	case 'g':	/* gigabyte */
952	case 'G':
953	    x <<= 30;	/* times 1024*1024*1024 */
954	    break;
955
956	case 'p':	/* partition start */
957	case 'P':	/* partition start */
958	case 'l':	/* partition length */
959	case 'L':	/* partition length */
960	    errx(1, "%s: not supported yet %s", arg, msg);
961	    /* notreached */
962	}
963    }
964    return x;
965}
966
967/*
968 * Check a volume label.
969 */
970static int
971oklabel(const char *src)
972{
973    int c, i;
974
975    for (i = 0; i <= 11; i++) {
976	c = (u_char)*src++;
977	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
978	    break;
979    }
980    return i && !c;
981}
982
983/*
984 * Make a volume label.
985 */
986static void
987mklabel(u_int8_t *dest, const char *src)
988{
989    int c, i;
990
991    for (i = 0; i < 11; i++) {
992	c = *src ? toupper((unsigned char)*src++) : ' ';
993	*dest++ = !i && c == '\xe5' ? 5 : c;
994    }
995}
996
997/*
998 * Copy string, padding with spaces.
999 */
1000static void
1001setstr(u_int8_t *dest, const char *src, size_t len)
1002{
1003    while (len--)
1004	*dest++ = *src ? *src++ : ' ';
1005}
1006
1007/*
1008 * Print usage message.
1009 */
1010static void
1011usage(void)
1012{
1013    fprintf(stderr,
1014	    "usage: %s [ -options ] special [disktype]\n", getprogname());
1015    fprintf(stderr, "where the options are:\n");
1016    fprintf(stderr, "\t-N don't create file system: "
1017	    "just print out parameters\n");
1018    fprintf(stderr, "\t-B get bootstrap from file\n");
1019    fprintf(stderr, "\t-F FAT type (12, 16, or 32)\n");
1020    fprintf(stderr, "\t-I volume ID\n");
1021    fprintf(stderr, "\t-L volume label\n");
1022    fprintf(stderr, "\t-O OEM string\n");
1023    fprintf(stderr, "\t-S bytes/sector\n");
1024    fprintf(stderr, "\t-a sectors/FAT\n");
1025    fprintf(stderr, "\t-b block size\n");
1026    fprintf(stderr, "\t-c sectors/cluster\n");
1027    fprintf(stderr, "\t-e root directory entries\n");
1028    fprintf(stderr, "\t-f standard format\n");
1029    fprintf(stderr, "\t-h drive heads\n");
1030    fprintf(stderr, "\t-i file system info sector\n");
1031    fprintf(stderr, "\t-k backup boot sector\n");
1032    fprintf(stderr, "\t-m media descriptor\n");
1033    fprintf(stderr, "\t-n number of FATs\n");
1034    fprintf(stderr, "\t-o hidden sectors\n");
1035    fprintf(stderr, "\t-r reserved sectors\n");
1036    fprintf(stderr, "\t-s file system size (sectors)\n");
1037    fprintf(stderr, "\t-u sectors/track\n");
1038    exit(1);
1039}
1040
1041void
1042infohandler(int sig)
1043{
1044    got_siginfo = 1;
1045}
1046