xref: /netbsd-src/sbin/newfs_msdos/mkfs_msdos.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: mkfs_msdos.c,v 1.9 2014/01/05 12:52:39 martin 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 #if HAVE_NBTOOL_CONFIG_H
31 #include "nbtool_config.h"
32 #endif
33 
34 #include <sys/cdefs.h>
35 #ifndef lint
36 #if 0
37 static const char rcsid[] =
38   "$FreeBSD: src/sbin/newfs_msdos/newfs_msdos.c,v 1.15 2000/10/10 01:49:37 wollman Exp $";
39 #else
40 __RCSID("$NetBSD: mkfs_msdos.c,v 1.9 2014/01/05 12:52:39 martin Exp $");
41 #endif
42 #endif /* not lint */
43 
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <sys/stat.h>
47 #include <sys/time.h>
48 #ifndef MAKEFS
49 #include <sys/mount.h>
50 #include <sys/disk.h>
51 #endif
52 
53 #include <ctype.h>
54 #include <err.h>
55 #include <errno.h>
56 #include <fcntl.h>
57 #include <paths.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <time.h>
62 #include <unistd.h>
63 #include <signal.h>
64 
65 #include <util.h>
66 #include <disktab.h>
67 
68 #ifndef MAKEFS
69 #include "partutil.h"
70 #endif
71 #include "mkfs_msdos.h"
72 
73 #define MAXU16	  0xffff	/* maximum unsigned 16-bit quantity */
74 #define BPN	  4		/* bits per nibble */
75 #define NPB	  2		/* nibbles per byte */
76 
77 #define DOSMAGIC  0xaa55	/* DOS magic number */
78 #define MINBPS	  512		/* minimum bytes per sector */
79 #define MAXSPC	  128		/* maximum sectors per cluster */
80 #define MAXNFT	  16		/* maximum number of FATs */
81 #define DEFBLK	  4096		/* default block size */
82 #define DEFBLK16  2048		/* default block size FAT16 */
83 #define DEFRDE	  512		/* default root directory entries */
84 #define RESFTE	  2		/* reserved FAT entries */
85 #define MINCLS12  1		/* minimum FAT12 clusters */
86 #define MINCLS16  0xff5		/* minimum FAT16 clusters */
87 #define MINCLS32  0xfff5	/* minimum FAT32 clusters */
88 #define MAXCLS12  0xff4 	/* maximum FAT12 clusters */
89 #define MAXCLS16  0xfff4	/* maximum FAT16 clusters */
90 #define MAXCLS32  0xffffff4	/* maximum FAT32 clusters */
91 
92 #define mincls(fat_type)  ((fat_type) == 12 ? MINCLS12 :	\
93 		      (fat_type) == 16 ? MINCLS16 :	\
94 				    MINCLS32)
95 
96 #define maxcls(fat_type)  ((fat_type) == 12 ? MAXCLS12 :	\
97 		      (fat_type) == 16 ? MAXCLS16 :	\
98 				    MAXCLS32)
99 
100 #define mk1(p, x)				\
101     (p) = (u_int8_t)(x)
102 
103 #define mk2(p, x)				\
104     (p)[0] = (u_int8_t)(x),			\
105     (p)[1] = (u_int8_t)((x) >> 010)
106 
107 #define mk4(p, x)				\
108     (p)[0] = (u_int8_t)(x),			\
109     (p)[1] = (u_int8_t)((x) >> 010),		\
110     (p)[2] = (u_int8_t)((x) >> 020),		\
111     (p)[3] = (u_int8_t)((x) >> 030)
112 
113 struct bs {
114     u_int8_t jmp[3];		/* bootstrap entry point */
115     u_int8_t oem[8];		/* OEM name and version */
116 };
117 
118 struct bsbpb {
119     u_int8_t bps[2];		/* bytes per sector */
120     u_int8_t spc;		/* sectors per cluster */
121     u_int8_t res[2];		/* reserved sectors */
122     u_int8_t nft;		/* number of FATs */
123     u_int8_t rde[2];		/* root directory entries */
124     u_int8_t sec[2];		/* total sectors */
125     u_int8_t mid;		/* media descriptor */
126     u_int8_t spf[2];		/* sectors per FAT */
127     u_int8_t spt[2];		/* sectors per track */
128     u_int8_t hds[2];		/* drive heads */
129     u_int8_t hid[4];		/* hidden sectors */
130     u_int8_t bsec[4];		/* big total sectors */
131 };
132 
133 struct bsxbpb {
134     u_int8_t bspf[4];		/* big sectors per FAT */
135     u_int8_t xflg[2];		/* FAT control flags */
136     u_int8_t vers[2];		/* file system version */
137     u_int8_t rdcl[4];		/* root directory start cluster */
138     u_int8_t infs[2];		/* file system info sector */
139     u_int8_t bkbs[2];		/* backup boot sector */
140     u_int8_t rsvd[12];		/* reserved */
141 };
142 
143 struct bsx {
144     u_int8_t drv;		/* drive number */
145     u_int8_t rsvd;		/* reserved */
146     u_int8_t sig;		/* extended boot signature */
147     u_int8_t volid[4];		/* volume ID number */
148     u_int8_t label[11]; 	/* volume label */
149     u_int8_t type[8];		/* file system type */
150 };
151 
152 struct de {
153     u_int8_t namext[11];	/* name and extension */
154     u_int8_t attr;		/* attributes */
155     u_int8_t rsvd[10];		/* reserved */
156     u_int8_t time[2];		/* creation time */
157     u_int8_t date[2];		/* creation date */
158     u_int8_t clus[2];		/* starting cluster */
159     u_int8_t size[4];		/* size */
160 };
161 
162 struct bpb {
163     u_int bps;			/* bytes per sector */
164     u_int spc;			/* sectors per cluster */
165     u_int res;			/* reserved sectors */
166     u_int nft;			/* number of FATs */
167     u_int rde;			/* root directory entries */
168     u_int sec;			/* total sectors */
169     u_int mid;			/* media descriptor */
170     u_int spf;			/* sectors per FAT */
171     u_int spt;			/* sectors per track */
172     u_int hds;			/* drive heads */
173     u_int hid;			/* hidden sectors */
174     u_int bsec; 		/* big total sectors */
175     u_int bspf; 		/* big sectors per FAT */
176     u_int rdcl; 		/* root directory start cluster */
177     u_int infs; 		/* file system info sector */
178     u_int bkbs; 		/* backup boot sector */
179 };
180 
181 #define INIT(a, b, c, d, e, f, g, h, i, j) \
182     { .bps = a, .spc = b, .res = c, .nft = d, .rde = e, \
183       .sec = f, .mid = g, .spf = h, .spt = i, .hds = j, }
184 static struct {
185     const char *name;
186     struct bpb bpb;
187 } stdfmt[] = {
188     {"160",  INIT(512, 1, 1, 2,  64,  320, 0xfe, 1,  8, 1)},
189     {"180",  INIT(512, 1, 1, 2,  64,  360, 0xfc, 2,  9, 1)},
190     {"320",  INIT(512, 2, 1, 2, 112,  640, 0xff, 1,  8, 2)},
191     {"360",  INIT(512, 2, 1, 2, 112,  720, 0xfd, 2,  9, 2)},
192     {"640",  INIT(512, 2, 1, 2, 112, 1280, 0xfb, 2,  8, 2)},
193     {"720",  INIT(512, 2, 1, 2, 112, 1440, 0xf9, 3,  9, 2)},
194     {"1200", INIT(512, 1, 1, 2, 224, 2400, 0xf9, 7, 15, 2)},
195     {"1232", INIT(1024,1, 1, 2, 192, 1232, 0xfe, 2,  8, 2)},
196     {"1440", INIT(512, 1, 1, 2, 224, 2880, 0xf0, 9, 18, 2)},
197     {"2880", INIT(512, 2, 1, 2, 240, 5760, 0xf0, 9, 36, 2)}
198 };
199 
200 static u_int8_t bootcode[] = {
201     0xfa,			/* cli		    */
202     0x31, 0xc0, 		/* xor	   ax,ax    */
203     0x8e, 0xd0, 		/* mov	   ss,ax    */
204     0xbc, 0x00, 0x7c,		/* mov	   sp,7c00h */
205     0xfb,			/* sti		    */
206     0x8e, 0xd8, 		/* mov	   ds,ax    */
207     0xe8, 0x00, 0x00,		/* call    $ + 3    */
208     0x5e,			/* pop	   si	    */
209     0x83, 0xc6, 0x19,		/* add	   si,+19h  */
210     0xbb, 0x07, 0x00,		/* mov	   bx,0007h */
211     0xfc,			/* cld		    */
212     0xac,			/* lodsb	    */
213     0x84, 0xc0, 		/* test    al,al    */
214     0x74, 0x06, 		/* jz	   $ + 8    */
215     0xb4, 0x0e, 		/* mov	   ah,0eh   */
216     0xcd, 0x10, 		/* int	   10h	    */
217     0xeb, 0xf5, 		/* jmp	   $ - 9    */
218     0x30, 0xe4, 		/* xor	   ah,ah    */
219     0xcd, 0x16, 		/* int	   16h	    */
220     0xcd, 0x19, 		/* int	   19h	    */
221     0x0d, 0x0a,
222     'N', 'o', 'n', '-', 's', 'y', 's', 't',
223     'e', 'm', ' ', 'd', 'i', 's', 'k',
224     0x0d, 0x0a,
225     'P', 'r', 'e', 's', 's', ' ', 'a', 'n',
226     'y', ' ', 'k', 'e', 'y', ' ', 't', 'o',
227     ' ', 'r', 'e', 'b', 'o', 'o', 't',
228     0x0d, 0x0a,
229     0
230 };
231 
232 static int got_siginfo = 0; /* received a SIGINFO */
233 
234 #ifndef MAKEFS
235 static int check_mounted(const char *, mode_t);
236 #endif
237 static int getstdfmt(const char *, struct bpb *);
238 static int getbpbinfo(int, const char *, const char *, int, struct bpb *, int);
239 static void print_bpb(struct bpb *);
240 static int ckgeom(const char *, u_int, const char *);
241 static int oklabel(const char *);
242 static void mklabel(u_int8_t *, const char *);
243 static void setstr(u_int8_t *, const char *, size_t);
244 static void infohandler(int sig);
245 
246 int
247 mkfs_msdos(const char *fname, const char *dtype, const struct msdos_options *op)
248 {
249     char buf[MAXPATHLEN];
250     struct stat sb;
251     struct timeval tv;
252     struct bpb bpb;
253     struct tm *tm;
254     struct bs *bs;
255     struct bsbpb *bsbpb;
256     struct bsxbpb *bsxbpb;
257     struct bsx *bsx;
258     struct de *de;
259     u_int8_t *img;
260     const char *bname;
261     ssize_t n;
262     time_t now;
263     u_int bss, rds, cls, dir, lsn, x, x1, x2;
264     int ch, fd, fd1;
265     struct msdos_options o = *op;
266     int oflags = O_RDWR | O_CREAT;
267 
268     if (o.block_size && o.sectors_per_cluster) {
269 	warnx("Cannot specify both block size and sectors per cluster");
270 	return -1;
271     }
272     if (o.OEM_string && strlen(o.OEM_string) > 8) {
273 	warnx("%s: bad OEM string", o.OEM_string);
274 	return -1;
275     }
276     if (o.create_size) {
277 	if (o.no_create) {
278 	    warnx("create (-C) is incompatible with -N");
279 	    return -1;
280 	}
281 	if (o.offset == 0)
282 		oflags |= O_TRUNC;
283 	fd = open(fname, oflags, 0644);
284 	if (fd == -1) {
285 	    warnx("failed to create %s", fname);
286 	    return -1;
287 	}
288 	(void)lseek(fd, o.create_size - 1, SEEK_SET);
289 	if (write(fd, "\0", 1) != 1) {
290 	    warn("failed to set file size");
291 	    return -1;
292 	}
293 	(void)lseek(fd, 0, SEEK_SET);
294     } else if ((fd = open(fname, o.no_create ? O_RDONLY : O_RDWR)) == -1 ||
295 	fstat(fd, &sb)) {
296 	warn("%s", fname);
297 	return -1;
298     }
299 #ifndef MAKEFS
300     if (!o.no_create)
301 	if (check_mounted(fname, sb.st_mode) == -1)
302 	    return -1;
303 #endif
304     if (!S_ISCHR(sb.st_mode) && !o.create_size) {
305 	warnx("warning, %s is not a character device", fname);
306 	return -1;
307     }
308     if (o.offset && o.offset != lseek(fd, o.offset, SEEK_SET)) {
309 	warnx("cannot seek to %jd", (intmax_t)o.offset);
310 	return -1;
311     }
312     memset(&bpb, 0, sizeof(bpb));
313     if (o.floppy) {
314 	if (getstdfmt(o.floppy, &bpb) == -1)
315 	    return -1;
316 	bpb.bsec = bpb.sec;
317 	bpb.sec = 0;
318 	bpb.bspf = bpb.spf;
319 	bpb.spf = 0;
320     }
321     if (o.drive_heads)
322 	bpb.hds = o.drive_heads;
323     if (o.sectors_per_track)
324 	bpb.spt = o.sectors_per_track;
325     if (o.bytes_per_sector)
326 	bpb.bps = o.bytes_per_sector;
327     if (o.size)
328 	bpb.bsec = o.size;
329     if (o.hidden_sectors_set)
330 	bpb.hid = o.hidden_sectors;
331     if (!(o.floppy || (o.drive_heads && o.sectors_per_track &&
332 	o.bytes_per_sector && o.size && o.hidden_sectors_set))) {
333 	if (getbpbinfo(fd, fname, dtype, o.hidden_sectors_set, &bpb,
334 	    o.create_size != 0) == -1)
335 	    return -1;
336 	bpb.bsec -= (o.offset / bpb.bps);
337 	if (bpb.spc == 0) {     /* set defaults */
338 	    if (bpb.bsec <= 6000)       /* about 3MB -> 512 bytes */
339 		bpb.spc = 1;
340 	    else if (bpb.bsec <= (1<<17)) /* 64M -> 4k */
341 		bpb.spc = 8;
342 	    else if (bpb.bsec <= (1<<19)) /* 256M -> 8k */
343 		bpb.spc = 16;
344 	    else if (bpb.bsec <= (1<<21)) /* 1G -> 16k */
345 		bpb.spc = 32;
346 	    else
347 		bpb.spc = 64;           /* otherwise 32k */
348 	}
349     }
350 
351     if (o.volume_label && !oklabel(o.volume_label)) {
352 	warnx("%s: bad volume label", o.volume_label);
353 	return -1;
354     }
355 
356     switch (o.fat_type) {
357     case 0:
358 	if (o.floppy)
359 	    o.fat_type = 12;
360 	else if (!o.directory_entries && (o.info_sector || o.backup_sector))
361 	    o.fat_type = 32;
362 	break;
363     case 12:
364     case 16:
365 	if (o.info_sector) {
366 	    warnx("Cannot specify info sector with FAT%u", o.fat_type);
367 	    return -1;
368 	}
369 	if (o.backup_sector) {
370 	    warnx("Cannot specify backup sector with FAT%u", o.fat_type);
371 	    return -1;
372 	}
373 	break;
374     case 32:
375 	if (o.directory_entries) {
376 	    warnx("Cannot specify directory entries with FAT32");
377 	    return -1;
378 	}
379 	break;
380     default:
381 	warnx("%d: bad FAT type", o.fat_type);
382 	return -1;
383     }
384     if (!powerof2(bpb.bps)) {
385 	warnx("bytes/sector (%u) is not a power of 2", bpb.bps);
386 	return -1;
387     }
388     if (bpb.bps < MINBPS) {
389 	warnx("bytes/sector (%u) is too small; minimum is %u",
390 	     bpb.bps, MINBPS);
391 	return -1;
392     }
393 
394     if (o.floppy && o.fat_type == 32)
395 	bpb.rde = 0;
396     if (o.block_size) {
397 	if (!powerof2(o.block_size)) {
398 	    warnx("block size (%u) is not a power of 2", o.block_size);
399 	    return -1;
400 	}
401 	if (o.block_size < bpb.bps) {
402 	    warnx("block size (%u) is too small; minimum is %u",
403 		o.block_size, bpb.bps);
404 	    return -1;
405 	}
406 	if (o.block_size > bpb.bps * MAXSPC) {
407 	    warnx("block size (%u) is too large; maximum is %u",
408 		o.block_size, bpb.bps * MAXSPC);
409 	    return -1;
410 	}
411 	bpb.spc = o.block_size / bpb.bps;
412     }
413     if (o.sectors_per_cluster) {
414 	if (!powerof2(o.sectors_per_cluster)) {
415 	    warnx("sectors/cluster (%u) is not a power of 2",
416 		o.sectors_per_cluster);
417 	    return -1;
418 	}
419 	bpb.spc = o.sectors_per_cluster;
420     }
421     if (o.reserved_sectors)
422 	bpb.res = o.reserved_sectors;
423     if (o.num_FAT) {
424 	if (o.num_FAT > MAXNFT) {
425 	    warnx("number of FATs (%u) is too large; maximum is %u",
426 		 o.num_FAT, MAXNFT);
427 	    return -1;
428 	}
429 	bpb.nft = o.num_FAT;
430     }
431     if (o.directory_entries)
432 	bpb.rde = o.directory_entries;
433     if (o.media_descriptor_set) {
434 	if (o.media_descriptor < 0xf0) {
435 	    warnx("illegal media descriptor (%#x)", o.media_descriptor);
436 	    return -1;
437 	}
438 	bpb.mid = o.media_descriptor;
439     }
440     if (o.sectors_per_fat)
441 	bpb.bspf = o.sectors_per_fat;
442     if (o.info_sector)
443 	bpb.infs = o.info_sector;
444     if (o.backup_sector)
445 	bpb.bkbs = o.backup_sector;
446     bss = 1;
447     bname = NULL;
448     fd1 = -1;
449     if (o.bootstrap) {
450 	bname = o.bootstrap;
451 	if (!strchr(bname, '/')) {
452 	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
453 	    if (!(bname = strdup(buf))) {
454 		warn(NULL);
455 		return -1;
456 	    }
457 	}
458 	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb)) {
459 	    warn("%s", bname);
460 	    return -1;
461 	}
462 	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bps ||
463 	    sb.st_size < bpb.bps || sb.st_size > bpb.bps * MAXU16) {
464 	    warnx("%s: inappropriate file type or format", bname);
465 	    return -1;
466 	}
467 	bss = sb.st_size / bpb.bps;
468     }
469     if (!bpb.nft)
470 	bpb.nft = 2;
471     if (!o.fat_type) {
472 	if (bpb.bsec < (bpb.res ? bpb.res : bss) +
473 	    howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
474 		    ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
475 	    bpb.nft +
476 	    howmany(bpb.rde ? bpb.rde : DEFRDE,
477 		    bpb.bps / sizeof(struct de)) +
478 	    (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
479 	    (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
480 	    o.fat_type = 12;
481 	else if (bpb.rde || bpb.bsec <
482 		 (bpb.res ? bpb.res : bss) +
483 		 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
484 		 howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
485 		 (MAXCLS16 + 1) *
486 		 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
487 	    o.fat_type = 16;
488 	else
489 	    o.fat_type = 32;
490     }
491     x = bss;
492     if (o.fat_type == 32) {
493 	if (!bpb.infs) {
494 	    if (x == MAXU16 || x == bpb.bkbs) {
495 		warnx("no room for info sector");
496 		return -1;
497 	    }
498 	    bpb.infs = x;
499 	}
500 	if (bpb.infs != MAXU16 && x <= bpb.infs)
501 	    x = bpb.infs + 1;
502 	if (!bpb.bkbs) {
503 	    if (x == MAXU16) {
504 		warnx("no room for backup sector");
505 		return -1;
506 	    }
507 	    bpb.bkbs = x;
508 	} else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs) {
509 	    warnx("backup sector would overwrite info sector");
510 	    return -1;
511 	}
512 	if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
513 	    x = bpb.bkbs + 1;
514     }
515     if (!bpb.res)
516 	bpb.res = o.fat_type == 32 ? MAX(x, MAX(16384 / bpb.bps, 4)) : x;
517     else if (bpb.res < x) {
518 	warnx("too few reserved sectors (need %d have %d)", x, bpb.res);
519 	return -1;
520     }
521     if (o.fat_type != 32 && !bpb.rde)
522 	bpb.rde = DEFRDE;
523     rds = howmany(bpb.rde, bpb.bps / sizeof(struct de));
524     if (!bpb.spc)
525 	for (bpb.spc = howmany(o.fat_type == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
526 	     bpb.spc < MAXSPC &&
527 	     bpb.res +
528 	     howmany((RESFTE + maxcls(o.fat_type)) * (o.fat_type / BPN),
529 		     bpb.bps * NPB) * bpb.nft +
530 	     rds +
531 	     (u_int64_t)(maxcls(o.fat_type) + 1) * bpb.spc <= bpb.bsec;
532 	     bpb.spc <<= 1);
533     if (o.fat_type != 32 && bpb.bspf > MAXU16) {
534 	warnx("too many sectors/FAT for FAT12/16");
535 	return -1;
536     }
537     x1 = bpb.res + rds;
538     x = bpb.bspf ? bpb.bspf : 1;
539     if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec) {
540 	warnx("meta data exceeds file system size");
541 	return -1;
542     }
543     x1 += x * bpb.nft;
544     x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
545 	(bpb.spc * bpb.bps * NPB + o.fat_type / BPN * bpb.nft);
546     x2 = howmany((RESFTE + MIN(x, maxcls(o.fat_type))) * (o.fat_type / BPN),
547 		 bpb.bps * NPB);
548     if (!bpb.bspf) {
549 	bpb.bspf = x2;
550 	x1 += (bpb.bspf - 1) * bpb.nft;
551     }
552     cls = (bpb.bsec - x1) / bpb.spc;
553     x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (o.fat_type / BPN) - RESFTE;
554     if (cls > x)
555 	cls = x;
556     if (bpb.bspf < x2) {
557 	warnx("warning: sectors/FAT limits file system to %u clusters",
558 	      cls);
559 	return -1;
560     }
561     if (cls < mincls(o.fat_type)) {
562 	warnx("%u clusters too few clusters for FAT%u, need %u", cls,
563 	    o.fat_type, mincls(o.fat_type));
564 	return -1;
565     }
566     if (cls > maxcls(o.fat_type)) {
567 	cls = maxcls(o.fat_type);
568 	bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
569 	warnx("warning: FAT type limits file system to %u sectors",
570 	      bpb.bsec);
571 	return -1;
572     }
573     printf("%s: %u sector%s in %u FAT%u cluster%s "
574 	   "(%u bytes/cluster)\n", fname, cls * bpb.spc,
575 	   cls * bpb.spc == 1 ? "" : "s", cls, o.fat_type,
576 	   cls == 1 ? "" : "s", bpb.bps * bpb.spc);
577     if (!bpb.mid)
578 	bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
579     if (o.fat_type == 32)
580 	bpb.rdcl = RESFTE;
581     if (bpb.hid + bpb.bsec <= MAXU16) {
582 	bpb.sec = bpb.bsec;
583 	bpb.bsec = 0;
584     }
585     if (o.fat_type != 32) {
586 	bpb.spf = bpb.bspf;
587 	bpb.bspf = 0;
588     }
589     ch = 0;
590     if (o.fat_type == 12)
591 	ch = 1;			/* 001 Primary DOS with 12 bit FAT */
592     else if (o.fat_type == 16) {
593 	if (bpb.bsec == 0)
594 	    ch = 4;		/* 004 Primary DOS with 16 bit FAT <32M */
595 	else
596 	    ch = 6;		/* 006 Primary 'big' DOS, 16-bit FAT (> 32MB) */
597 				/*
598 				 * XXX: what about:
599 				 * 014 DOS (16-bit FAT) - LBA
600 				 *  ?
601 				 */
602     } else if (o.fat_type == 32) {
603 	ch = 11;		/* 011 Primary DOS with 32 bit FAT */
604 				/*
605 				 * XXX: what about:
606 				 * 012 Primary DOS with 32 bit FAT - LBA
607 				 *  ?
608 				 */
609     }
610     if (ch != 0)
611 	printf("MBR type: %d\n", ch);
612     print_bpb(&bpb);
613     if (!o.no_create) {
614 	gettimeofday(&tv, NULL);
615 	now = tv.tv_sec;
616 	tm = localtime(&now);
617 	if (!(img = malloc(bpb.bps)))
618 	    err(1, NULL);
619 	dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;
620 #ifdef SIGINFO
621 	signal(SIGINFO, infohandler);
622 #endif
623 	for (lsn = 0; lsn < dir + (o.fat_type == 32 ? bpb.spc : rds); lsn++) {
624 	    if (got_siginfo) {
625 		fprintf(stderr,"%s: writing sector %u of %u (%u%%)\n",
626 		    fname,lsn,(dir + (o.fat_type == 32 ? bpb.spc : rds)),
627 		    (lsn*100)/(dir + (o.fat_type == 32 ? bpb.spc : rds)));
628 		got_siginfo = 0;
629 	    }
630 	    x = lsn;
631 	    if (o.bootstrap &&
632 		o.fat_type == 32 && bpb.bkbs != MAXU16 &&
633 		bss <= bpb.bkbs && x >= bpb.bkbs) {
634 		x -= bpb.bkbs;
635 		if (!x && lseek(fd1, o.offset, SEEK_SET)) {
636 		    warn("%s", bname);
637 		    return -1;
638 		}
639 	    }
640 	    if (o.bootstrap && x < bss) {
641 		if ((n = read(fd1, img, bpb.bps)) == -1) {
642 		    warn("%s", bname);
643 		    return -1;
644 		}
645 		if ((size_t)n != bpb.bps) {
646 		    warnx("%s: can't read sector %u", bname, x);
647 		    return -1;
648 		}
649 	    } else
650 		memset(img, 0, bpb.bps);
651 	    if (!lsn ||
652 	      (o.fat_type == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
653 		x1 = sizeof(struct bs);
654 		bsbpb = (struct bsbpb *)(img + x1);
655 		mk2(bsbpb->bps, bpb.bps);
656 		mk1(bsbpb->spc, bpb.spc);
657 		mk2(bsbpb->res, bpb.res);
658 		mk1(bsbpb->nft, bpb.nft);
659 		mk2(bsbpb->rde, bpb.rde);
660 		mk2(bsbpb->sec, bpb.sec);
661 		mk1(bsbpb->mid, bpb.mid);
662 		mk2(bsbpb->spf, bpb.spf);
663 		mk2(bsbpb->spt, bpb.spt);
664 		mk2(bsbpb->hds, bpb.hds);
665 		mk4(bsbpb->hid, bpb.hid);
666 		mk4(bsbpb->bsec, bpb.bsec);
667 		x1 += sizeof(struct bsbpb);
668 		if (o.fat_type == 32) {
669 		    bsxbpb = (struct bsxbpb *)(img + x1);
670 		    mk4(bsxbpb->bspf, bpb.bspf);
671 		    mk2(bsxbpb->xflg, 0);
672 		    mk2(bsxbpb->vers, 0);
673 		    mk4(bsxbpb->rdcl, bpb.rdcl);
674 		    mk2(bsxbpb->infs, bpb.infs);
675 		    mk2(bsxbpb->bkbs, bpb.bkbs);
676 		    x1 += sizeof(struct bsxbpb);
677 		}
678 		bsx = (struct bsx *)(img + x1);
679 		mk1(bsx->sig, 0x29);
680 		if (o.volume_id_set)
681 		    x = o.volume_id;
682 		else
683 		    x = (((u_int)(1 + tm->tm_mon) << 8 |
684 			  (u_int)tm->tm_mday) +
685 			 ((u_int)tm->tm_sec << 8 |
686 			  (u_int)(tv.tv_usec / 10))) << 16 |
687 			((u_int)(1900 + tm->tm_year) +
688 			 ((u_int)tm->tm_hour << 8 |
689 			  (u_int)tm->tm_min));
690 		mk4(bsx->volid, x);
691 		mklabel(bsx->label, o.volume_label ? o.volume_label : "NO NAME");
692 		snprintf(buf, sizeof(buf), "FAT%u", o.fat_type);
693 		setstr(bsx->type, buf, sizeof(bsx->type));
694 		if (!o.bootstrap) {
695 		    x1 += sizeof(struct bsx);
696 		    bs = (struct bs *)img;
697 		    mk1(bs->jmp[0], 0xeb);
698 		    mk1(bs->jmp[1], x1 - 2);
699 		    mk1(bs->jmp[2], 0x90);
700 		    setstr(bs->oem, o.OEM_string ? o.OEM_string : "NetBSD",
701 			   sizeof(bs->oem));
702 		    memcpy(img + x1, bootcode, sizeof(bootcode));
703 		    mk2(img + MINBPS - 2, DOSMAGIC);
704 		}
705 	    } else if (o.fat_type == 32 && bpb.infs != MAXU16 &&
706 		       (lsn == bpb.infs ||
707 			(bpb.bkbs != MAXU16 &&
708 			 lsn == bpb.bkbs + bpb.infs))) {
709 		mk4(img, 0x41615252);
710 		mk4(img + MINBPS - 28, 0x61417272);
711 		mk4(img + MINBPS - 24, 0xffffffff);
712 		mk4(img + MINBPS - 20, 0xffffffff);
713 		mk2(img + MINBPS - 2, DOSMAGIC);
714 	    } else if (lsn >= bpb.res && lsn < dir &&
715 		       !((lsn - bpb.res) %
716 			 (bpb.spf ? bpb.spf : bpb.bspf))) {
717 		mk1(img[0], bpb.mid);
718 		for (x = 1; x < o.fat_type * (o.fat_type == 32 ? 3U : 2U) / 8U; x++)
719 		    mk1(img[x], o.fat_type == 32 && x % 4 == 3 ? 0x0f : 0xff);
720 	    } else if (lsn == dir && o.volume_label) {
721 		de = (struct de *)img;
722 		mklabel(de->namext, o.volume_label);
723 		mk1(de->attr, 050);
724 		x = (u_int)tm->tm_hour << 11 |
725 		    (u_int)tm->tm_min << 5 |
726 		    (u_int)tm->tm_sec >> 1;
727 		mk2(de->time, x);
728 		x = (u_int)(tm->tm_year - 80) << 9 |
729 		    (u_int)(tm->tm_mon + 1) << 5 |
730 		    (u_int)tm->tm_mday;
731 		mk2(de->date, x);
732 	    }
733 	    if ((n = write(fd, img, bpb.bps)) == -1) {
734 		warn("%s", fname);
735 		return -1;
736 	    }
737 	    if ((size_t)n != bpb.bps) {
738 		warnx("%s: can't write sector %u", fname, lsn);
739 		return -1;
740 	    }
741 	}
742     }
743     return 0;
744 }
745 
746 #ifndef MAKEFS
747 /*
748  * return -1 with error if file system is mounted.
749  */
750 static int
751 check_mounted(const char *fname, mode_t mode)
752 {
753     struct statvfs *mp;
754     const char *s1, *s2;
755     size_t len;
756     int n, r;
757 
758     if (!(n = getmntinfo(&mp, MNT_NOWAIT))) {
759 	warn("getmntinfo");
760 	return -1;
761     }
762     len = strlen(_PATH_DEV);
763     s1 = fname;
764     if (!strncmp(s1, _PATH_DEV, len))
765 	s1 += len;
766     r = S_ISCHR(mode) && s1 != fname && *s1 == 'r';
767     for (; n--; mp++) {
768 	s2 = mp->f_mntfromname;
769 	if (!strncmp(s2, _PATH_DEV, len))
770 	    s2 += len;
771 	if ((r && s2 != mp->f_mntfromname && !strcmp(s1 + 1, s2)) ||
772 	    !strcmp(s1, s2)) {
773 	    warnx("%s is mounted on %s", fname, mp->f_mntonname);
774 	    return -1;
775 	}
776     }
777     return 0;
778 }
779 #endif
780 
781 /*
782  * Get a standard format.
783  */
784 static int
785 getstdfmt(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 	warnx("%s: unknown standard format", fmt);
793 	return -1;
794     }
795     *bpb = stdfmt[i].bpb;
796     return 0;
797 }
798 
799 /*
800  * Get disk slice, partition, and geometry information.
801  */
802 static int
803 getbpbinfo(int fd, const char *fname, const char *dtype, int iflag,
804     struct bpb *bpb, int create)
805 {
806     const char *s1, *s2;
807     int part;
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 #ifndef MAKEFS
821     int maxpartitions = getmaxpartitions();
822 
823     // XXX: Does not work with wedges
824     if (s2 && *s2 >= 'a' && *s2 <= 'a' + maxpartitions - 1) {
825 	part = *s2++ - 'a';
826     }
827 #endif
828     if (((part != -1) && ((!iflag && part != -1) || !bpb->bsec)) ||
829 	!bpb->bps || !bpb->spt || !bpb->hds) {
830 	u_int sector_size;
831 	u_int nsectors;
832 	u_int ntracks;
833 	u_int size;
834 #ifndef MAKEFS
835 	struct disk_geom geo;
836 	struct dkwedge_info dkw;
837 
838 	if (!create && getdiskinfo(fname, fd, NULL, &geo, &dkw) != -1) {
839 	    sector_size = geo.dg_secsize = 512;
840 	    nsectors = geo.dg_nsectors = 63;
841 	    ntracks = geo.dg_ntracks = 255;
842 	    size = dkw.dkw_size;
843 	} else
844 #endif
845 	{
846 	    struct stat st;
847 
848 	    if (fstat(fd, &st) == -1) {
849 		warnx("Can't get disk size for `%s'", fname);
850 		return -1;
851 	    }
852 	    /* create a fake geometry for a file image */
853 	    sector_size = 512;
854 	    nsectors = 63;
855 	    ntracks = 255;
856 	    size = st.st_size / sector_size;
857 	}
858 	if (!bpb->bps) {
859 	    if (ckgeom(fname, sector_size, "bytes/sector") == -1)
860 		return -1;
861 	    bpb->bps = sector_size;
862 	}
863 
864 	if (nsectors > 63) {
865 		/*
866 		 * The kernel doesn't accept BPB with spt > 63.
867 		 * (see sys/fs/msdosfs/msdosfs_vfsops.c:msdosfs_mountfs())
868 		 * If values taken from disklabel don't match these
869 		 * restrictions, use popular BIOS default values instead.
870 		 */
871 		nsectors = 63;
872 	}
873 	if (!bpb->spt) {
874 	    if (ckgeom(fname, nsectors, "sectors/track") == -1)
875 		return -1;
876 	    bpb->spt = nsectors;
877 	}
878 	if (!bpb->hds)
879 	    if (ckgeom(fname, ntracks, "drive heads") == -1)
880 		return -1;
881 	    bpb->hds = ntracks;
882 	if (!bpb->bsec)
883 	    bpb->bsec = size;
884     }
885     return 0;
886 }
887 
888 /*
889  * Print out BPB values.
890  */
891 static void
892 print_bpb(struct bpb *bpb)
893 {
894     printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
895 	   bpb->nft);
896     if (bpb->rde)
897 	printf(" rde=%u", bpb->rde);
898     if (bpb->sec)
899 	printf(" sec=%u", bpb->sec);
900     printf(" mid=%#x", bpb->mid);
901     if (bpb->spf)
902 	printf(" spf=%u", bpb->spf);
903     printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
904     if (bpb->bsec)
905 	printf(" bsec=%u", bpb->bsec);
906     if (!bpb->spf) {
907 	printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
908 	printf(" infs=");
909 	printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
910 	printf(" bkbs=");
911 	printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
912     }
913     printf("\n");
914 }
915 
916 /*
917  * Check a disk geometry value.
918  */
919 static int
920 ckgeom(const char *fname, u_int val, const char *msg)
921 {
922     if (!val) {
923 	warnx("%s: no default %s", fname, msg);
924 	return -1;
925     }
926     if (val > MAXU16) {
927 	warnx("%s: illegal %s", fname, msg);
928 	return -1;
929     }
930     return 0;
931 }
932 /*
933  * Check a volume label.
934  */
935 static int
936 oklabel(const char *src)
937 {
938     int c, i;
939 
940     for (i = 0; i <= 11; i++) {
941 	c = (u_char)*src++;
942 	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
943 	    break;
944     }
945     return i && !c;
946 }
947 
948 /*
949  * Make a volume label.
950  */
951 static void
952 mklabel(u_int8_t *dest, const char *src)
953 {
954     int c, i;
955 
956     for (i = 0; i < 11; i++) {
957 	c = *src ? toupper((unsigned char)*src++) : ' ';
958 	*dest++ = !i && c == '\xe5' ? 5 : c;
959     }
960 }
961 
962 /*
963  * Copy string, padding with spaces.
964  */
965 static void
966 setstr(u_int8_t *dest, const char *src, size_t len)
967 {
968     while (len--)
969 	*dest++ = *src ? *src++ : ' ';
970 }
971 
972 static void
973 infohandler(int sig)
974 {
975     got_siginfo = 1;
976 }
977