xref: /netbsd-src/sbin/newfs_msdos/mkfs_msdos.c (revision a4ddc2c8fb9af816efe3b1c375a5530aef0e89e9)
1 /*	$NetBSD: mkfs_msdos.c,v 1.7 2013/02/03 03:21:42 christos 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 1.7 2013/02/03 03:21:42 christos 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 	off_t pos;
278 	if (o.no_create) {
279 	    warnx("create (-C) is incompatible with -N");
280 	    return -1;
281 	}
282 	if (o.offset == 0)
283 		oflags |= O_TRUNC;
284 	fd = open(fname, oflags, 0644);
285 	if (fd == -1) {
286 	    warnx("failed to create %s", fname);
287 	    return -1;
288 	}
289 	pos = lseek(fd, o.create_size - 1, SEEK_SET);
290 	if (write(fd, "\0", 1) != 1) {
291 	    warn("failed to set file size");
292 	    return -1;
293 	}
294 	pos = lseek(fd, 0, SEEK_SET);
295     } else if ((fd = open(fname, o.no_create ? O_RDONLY : O_RDWR)) == -1 ||
296 	fstat(fd, &sb)) {
297 	warn("%s", fname);
298 	return -1;
299     }
300 #ifndef MAKEFS
301     if (!o.no_create)
302 	if (check_mounted(fname, sb.st_mode) == -1)
303 	    return -1;
304 #endif
305     if (!S_ISCHR(sb.st_mode) && !o.create_size) {
306 	warnx("warning, %s is not a character device", fname);
307 	return -1;
308     }
309     if (o.offset && o.offset != lseek(fd, o.offset, SEEK_SET)) {
310 	warnx("cannot seek to %jd", (intmax_t)o.offset);
311 	return -1;
312     }
313     memset(&bpb, 0, sizeof(bpb));
314     if (o.floppy) {
315 	if (getstdfmt(o.floppy, &bpb) == -1)
316 	    return -1;
317 	bpb.bsec = bpb.sec;
318 	bpb.sec = 0;
319 	bpb.bspf = bpb.spf;
320 	bpb.spf = 0;
321     }
322     if (o.drive_heads)
323 	bpb.hds = o.drive_heads;
324     if (o.sectors_per_track)
325 	bpb.spt = o.sectors_per_track;
326     if (o.bytes_per_sector)
327 	bpb.bps = o.bytes_per_sector;
328     if (o.size)
329 	bpb.bsec = o.size;
330     if (o.hidden_sectors_set)
331 	bpb.hid = o.hidden_sectors;
332     if (!(o.floppy || (o.drive_heads && o.sectors_per_track &&
333 	o.bytes_per_sector && o.size && o.hidden_sectors_set))) {
334 	if (getbpbinfo(fd, fname, dtype, o.hidden_sectors_set, &bpb,
335 	    o.create_size != 0) == -1)
336 	    return -1;
337 	bpb.bsec -= (o.offset / bpb.bps);
338 	if (bpb.spc == 0) {     /* set defaults */
339 	    if (bpb.bsec <= 6000)       /* about 3MB -> 512 bytes */
340 		bpb.spc = 1;
341 	    else if (bpb.bsec <= (1<<17)) /* 64M -> 4k */
342 		bpb.spc = 8;
343 	    else if (bpb.bsec <= (1<<19)) /* 256M -> 8k */
344 		bpb.spc = 16;
345 	    else if (bpb.bsec <= (1<<21)) /* 1G -> 16k */
346 		bpb.spc = 32;
347 	    else
348 		bpb.spc = 64;           /* otherwise 32k */
349 	}
350     }
351 
352     if (o.volume_label && !oklabel(o.volume_label)) {
353 	warnx("%s: bad volume label", o.volume_label);
354 	return -1;
355     }
356 
357     switch (o.fat_type) {
358     case 0:
359 	if (o.floppy)
360 	    o.fat_type = 12;
361 	else if (!o.directory_entries && (o.info_sector || o.backup_sector))
362 	    o.fat_type = 32;
363 	break;
364     case 12:
365     case 16:
366 	if (o.info_sector) {
367 	    warnx("Cannot specify info sector with FAT%u", o.fat_type);
368 	    return -1;
369 	}
370 	if (o.backup_sector) {
371 	    warnx("Cannot specify backup sector with FAT%u", o.fat_type);
372 	    return -1;
373 	}
374 	break;
375     case 32:
376 	if (o.directory_entries) {
377 	    warnx("Cannot specify directory entries with FAT32");
378 	    return -1;
379 	}
380 	break;
381     default:
382 	warnx("%d: bad FAT type", o.fat_type);
383 	return -1;
384     }
385     if (!powerof2(bpb.bps)) {
386 	warnx("bytes/sector (%u) is not a power of 2", bpb.bps);
387 	return -1;
388     }
389     if (bpb.bps < MINBPS) {
390 	warnx("bytes/sector (%u) is too small; minimum is %u",
391 	     bpb.bps, MINBPS);
392 	return -1;
393     }
394 
395     if (o.floppy && o.fat_type == 32)
396 	bpb.rde = 0;
397     if (o.block_size) {
398 	if (!powerof2(o.block_size)) {
399 	    warnx("block size (%u) is not a power of 2", o.block_size);
400 	    return -1;
401 	}
402 	if (o.block_size < bpb.bps) {
403 	    warnx("block size (%u) is too small; minimum is %u",
404 		o.block_size, bpb.bps);
405 	    return -1;
406 	}
407 	if (o.block_size > bpb.bps * MAXSPC) {
408 	    warnx("block size (%u) is too large; maximum is %u",
409 		o.block_size, bpb.bps * MAXSPC);
410 	    return -1;
411 	}
412 	bpb.spc = o.block_size / bpb.bps;
413     }
414     if (o.sectors_per_cluster) {
415 	if (!powerof2(o.sectors_per_cluster)) {
416 	    warnx("sectors/cluster (%u) is not a power of 2",
417 		o.sectors_per_cluster);
418 	    return -1;
419 	}
420 	bpb.spc = o.sectors_per_cluster;
421     }
422     if (o.reserved_sectors)
423 	bpb.res = o.reserved_sectors;
424     if (o.num_FAT) {
425 	if (o.num_FAT > MAXNFT) {
426 	    warnx("number of FATs (%u) is too large; maximum is %u",
427 		 o.num_FAT, MAXNFT);
428 	    return -1;
429 	}
430 	bpb.nft = o.num_FAT;
431     }
432     if (o.directory_entries)
433 	bpb.rde = o.directory_entries;
434     if (o.media_descriptor_set) {
435 	if (o.media_descriptor < 0xf0) {
436 	    warnx("illegal media descriptor (%#x)", o.media_descriptor);
437 	    return -1;
438 	}
439 	bpb.mid = o.media_descriptor;
440     }
441     if (o.sectors_per_fat)
442 	bpb.bspf = o.sectors_per_fat;
443     if (o.info_sector)
444 	bpb.infs = o.info_sector;
445     if (o.backup_sector)
446 	bpb.bkbs = o.backup_sector;
447     bss = 1;
448     bname = NULL;
449     fd1 = -1;
450     if (o.bootstrap) {
451 	bname = o.bootstrap;
452 	if (!strchr(bname, '/')) {
453 	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
454 	    if (!(bname = strdup(buf))) {
455 		warn(NULL);
456 		return -1;
457 	    }
458 	}
459 	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb)) {
460 	    warn("%s", bname);
461 	    return -1;
462 	}
463 	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bps ||
464 	    sb.st_size < bpb.bps || sb.st_size > bpb.bps * MAXU16) {
465 	    warnx("%s: inappropriate file type or format", bname);
466 	    return -1;
467 	}
468 	bss = sb.st_size / bpb.bps;
469     }
470     if (!bpb.nft)
471 	bpb.nft = 2;
472     if (!o.fat_type) {
473 	if (bpb.bsec < (bpb.res ? bpb.res : bss) +
474 	    howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
475 		    ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
476 	    bpb.nft +
477 	    howmany(bpb.rde ? bpb.rde : DEFRDE,
478 		    bpb.bps / sizeof(struct de)) +
479 	    (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
480 	    (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
481 	    o.fat_type = 12;
482 	else if (bpb.rde || bpb.bsec <
483 		 (bpb.res ? bpb.res : bss) +
484 		 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
485 		 howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
486 		 (MAXCLS16 + 1) *
487 		 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
488 	    o.fat_type = 16;
489 	else
490 	    o.fat_type = 32;
491     }
492     x = bss;
493     if (o.fat_type == 32) {
494 	if (!bpb.infs) {
495 	    if (x == MAXU16 || x == bpb.bkbs) {
496 		warnx("no room for info sector");
497 		return -1;
498 	    }
499 	    bpb.infs = x;
500 	}
501 	if (bpb.infs != MAXU16 && x <= bpb.infs)
502 	    x = bpb.infs + 1;
503 	if (!bpb.bkbs) {
504 	    if (x == MAXU16) {
505 		warnx("no room for backup sector");
506 		return -1;
507 	    }
508 	    bpb.bkbs = x;
509 	} else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs) {
510 	    warnx("backup sector would overwrite info sector");
511 	    return -1;
512 	}
513 	if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
514 	    x = bpb.bkbs + 1;
515     }
516     if (!bpb.res)
517 	bpb.res = o.fat_type == 32 ? MAX(x, MAX(16384 / bpb.bps, 4)) : x;
518     else if (bpb.res < x) {
519 	warnx("too few reserved sectors (need %d have %d)", x, bpb.res);
520 	return -1;
521     }
522     if (o.fat_type != 32 && !bpb.rde)
523 	bpb.rde = DEFRDE;
524     rds = howmany(bpb.rde, bpb.bps / sizeof(struct de));
525     if (!bpb.spc)
526 	for (bpb.spc = howmany(o.fat_type == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
527 	     bpb.spc < MAXSPC &&
528 	     bpb.res +
529 	     howmany((RESFTE + maxcls(o.fat_type)) * (o.fat_type / BPN),
530 		     bpb.bps * NPB) * bpb.nft +
531 	     rds +
532 	     (u_int64_t)(maxcls(o.fat_type) + 1) * bpb.spc <= bpb.bsec;
533 	     bpb.spc <<= 1);
534     if (o.fat_type != 32 && bpb.bspf > MAXU16) {
535 	warnx("too many sectors/FAT for FAT12/16");
536 	return -1;
537     }
538     x1 = bpb.res + rds;
539     x = bpb.bspf ? bpb.bspf : 1;
540     if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec) {
541 	warnx("meta data exceeds file system size");
542 	return -1;
543     }
544     x1 += x * bpb.nft;
545     x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
546 	(bpb.spc * bpb.bps * NPB + o.fat_type / BPN * bpb.nft);
547     x2 = howmany((RESFTE + MIN(x, maxcls(o.fat_type))) * (o.fat_type / BPN),
548 		 bpb.bps * NPB);
549     if (!bpb.bspf) {
550 	bpb.bspf = x2;
551 	x1 += (bpb.bspf - 1) * bpb.nft;
552     }
553     cls = (bpb.bsec - x1) / bpb.spc;
554     x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (o.fat_type / BPN) - RESFTE;
555     if (cls > x)
556 	cls = x;
557     if (bpb.bspf < x2) {
558 	warnx("warning: sectors/FAT limits file system to %u clusters",
559 	      cls);
560 	return -1;
561     }
562     if (cls < mincls(o.fat_type)) {
563 	warnx("%u clusters too few clusters for FAT%u, need %u", cls,
564 	    o.fat_type, mincls(o.fat_type));
565 	return -1;
566     }
567     if (cls > maxcls(o.fat_type)) {
568 	cls = maxcls(o.fat_type);
569 	bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
570 	warnx("warning: FAT type limits file system to %u sectors",
571 	      bpb.bsec);
572 	return -1;
573     }
574     printf("%s: %u sector%s in %u FAT%u cluster%s "
575 	   "(%u bytes/cluster)\n", fname, cls * bpb.spc,
576 	   cls * bpb.spc == 1 ? "" : "s", cls, o.fat_type,
577 	   cls == 1 ? "" : "s", bpb.bps * bpb.spc);
578     if (!bpb.mid)
579 	bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
580     if (o.fat_type == 32)
581 	bpb.rdcl = RESFTE;
582     if (bpb.hid + bpb.bsec <= MAXU16) {
583 	bpb.sec = bpb.bsec;
584 	bpb.bsec = 0;
585     }
586     if (o.fat_type != 32) {
587 	bpb.spf = bpb.bspf;
588 	bpb.bspf = 0;
589     }
590     ch = 0;
591     if (o.fat_type == 12)
592 	ch = 1;			/* 001 Primary DOS with 12 bit FAT */
593     else if (o.fat_type == 16) {
594 	if (bpb.bsec == 0)
595 	    ch = 4;		/* 004 Primary DOS with 16 bit FAT <32M */
596 	else
597 	    ch = 6;		/* 006 Primary 'big' DOS, 16-bit FAT (> 32MB) */
598 				/*
599 				 * XXX: what about:
600 				 * 014 DOS (16-bit FAT) - LBA
601 				 *  ?
602 				 */
603     } else if (o.fat_type == 32) {
604 	ch = 11;		/* 011 Primary DOS with 32 bit FAT */
605 				/*
606 				 * XXX: what about:
607 				 * 012 Primary DOS with 32 bit FAT - LBA
608 				 *  ?
609 				 */
610     }
611     if (ch != 0)
612 	printf("MBR type: %d\n", ch);
613     print_bpb(&bpb);
614     if (!o.no_create) {
615 	gettimeofday(&tv, NULL);
616 	now = tv.tv_sec;
617 	tm = localtime(&now);
618 	if (!(img = malloc(bpb.bps)))
619 	    err(1, NULL);
620 	dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;
621 #ifdef SIGINFO
622 	signal(SIGINFO, infohandler);
623 #endif
624 	for (lsn = 0; lsn < dir + (o.fat_type == 32 ? bpb.spc : rds); lsn++) {
625 	    if (got_siginfo) {
626 		fprintf(stderr,"%s: writing sector %u of %u (%u%%)\n",
627 		    fname,lsn,(dir + (o.fat_type == 32 ? bpb.spc : rds)),
628 		    (lsn*100)/(dir + (o.fat_type == 32 ? bpb.spc : rds)));
629 		got_siginfo = 0;
630 	    }
631 	    x = lsn;
632 	    if (o.bootstrap &&
633 		o.fat_type == 32 && bpb.bkbs != MAXU16 &&
634 		bss <= bpb.bkbs && x >= bpb.bkbs) {
635 		x -= bpb.bkbs;
636 		if (!x && lseek(fd1, o.offset, SEEK_SET)) {
637 		    warn("%s", bname);
638 		    return -1;
639 		}
640 	    }
641 	    if (o.bootstrap && x < bss) {
642 		if ((n = read(fd1, img, bpb.bps)) == -1) {
643 		    warn("%s", bname);
644 		    return -1;
645 		}
646 		if ((size_t)n != bpb.bps) {
647 		    warnx("%s: can't read sector %u", bname, x);
648 		    return -1;
649 		}
650 	    } else
651 		memset(img, 0, bpb.bps);
652 	    if (!lsn ||
653 	      (o.fat_type == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
654 		x1 = sizeof(struct bs);
655 		bsbpb = (struct bsbpb *)(img + x1);
656 		mk2(bsbpb->bps, bpb.bps);
657 		mk1(bsbpb->spc, bpb.spc);
658 		mk2(bsbpb->res, bpb.res);
659 		mk1(bsbpb->nft, bpb.nft);
660 		mk2(bsbpb->rde, bpb.rde);
661 		mk2(bsbpb->sec, bpb.sec);
662 		mk1(bsbpb->mid, bpb.mid);
663 		mk2(bsbpb->spf, bpb.spf);
664 		mk2(bsbpb->spt, bpb.spt);
665 		mk2(bsbpb->hds, bpb.hds);
666 		mk4(bsbpb->hid, bpb.hid);
667 		mk4(bsbpb->bsec, bpb.bsec);
668 		x1 += sizeof(struct bsbpb);
669 		if (o.fat_type == 32) {
670 		    bsxbpb = (struct bsxbpb *)(img + x1);
671 		    mk4(bsxbpb->bspf, bpb.bspf);
672 		    mk2(bsxbpb->xflg, 0);
673 		    mk2(bsxbpb->vers, 0);
674 		    mk4(bsxbpb->rdcl, bpb.rdcl);
675 		    mk2(bsxbpb->infs, bpb.infs);
676 		    mk2(bsxbpb->bkbs, bpb.bkbs);
677 		    x1 += sizeof(struct bsxbpb);
678 		}
679 		bsx = (struct bsx *)(img + x1);
680 		mk1(bsx->sig, 0x29);
681 		if (o.volume_id_set)
682 		    x = o.volume_id;
683 		else
684 		    x = (((u_int)(1 + tm->tm_mon) << 8 |
685 			  (u_int)tm->tm_mday) +
686 			 ((u_int)tm->tm_sec << 8 |
687 			  (u_int)(tv.tv_usec / 10))) << 16 |
688 			((u_int)(1900 + tm->tm_year) +
689 			 ((u_int)tm->tm_hour << 8 |
690 			  (u_int)tm->tm_min));
691 		mk4(bsx->volid, x);
692 		mklabel(bsx->label, o.volume_label ? o.volume_label : "NO NAME");
693 		snprintf(buf, sizeof(buf), "FAT%u", o.fat_type);
694 		setstr(bsx->type, buf, sizeof(bsx->type));
695 		if (!o.bootstrap) {
696 		    x1 += sizeof(struct bsx);
697 		    bs = (struct bs *)img;
698 		    mk1(bs->jmp[0], 0xeb);
699 		    mk1(bs->jmp[1], x1 - 2);
700 		    mk1(bs->jmp[2], 0x90);
701 		    setstr(bs->oem, o.OEM_string ? o.OEM_string : "NetBSD",
702 			   sizeof(bs->oem));
703 		    memcpy(img + x1, bootcode, sizeof(bootcode));
704 		    mk2(img + MINBPS - 2, DOSMAGIC);
705 		}
706 	    } else if (o.fat_type == 32 && bpb.infs != MAXU16 &&
707 		       (lsn == bpb.infs ||
708 			(bpb.bkbs != MAXU16 &&
709 			 lsn == bpb.bkbs + bpb.infs))) {
710 		mk4(img, 0x41615252);
711 		mk4(img + MINBPS - 28, 0x61417272);
712 		mk4(img + MINBPS - 24, 0xffffffff);
713 		mk4(img + MINBPS - 20, bpb.rdcl);
714 		mk2(img + MINBPS - 2, DOSMAGIC);
715 	    } else if (lsn >= bpb.res && lsn < dir &&
716 		       !((lsn - bpb.res) %
717 			 (bpb.spf ? bpb.spf : bpb.bspf))) {
718 		mk1(img[0], bpb.mid);
719 		for (x = 1; x < o.fat_type * (o.fat_type == 32 ? 3U : 2U) / 8U; x++)
720 		    mk1(img[x], o.fat_type == 32 && x % 4 == 3 ? 0x0f : 0xff);
721 	    } else if (lsn == dir && o.volume_label) {
722 		de = (struct de *)img;
723 		mklabel(de->namext, o.volume_label);
724 		mk1(de->attr, 050);
725 		x = (u_int)tm->tm_hour << 11 |
726 		    (u_int)tm->tm_min << 5 |
727 		    (u_int)tm->tm_sec >> 1;
728 		mk2(de->time, x);
729 		x = (u_int)(tm->tm_year - 80) << 9 |
730 		    (u_int)(tm->tm_mon + 1) << 5 |
731 		    (u_int)tm->tm_mday;
732 		mk2(de->date, x);
733 	    }
734 	    if ((n = write(fd, img, bpb.bps)) == -1) {
735 		warn("%s", fname);
736 		return -1;
737 	    }
738 	    if ((size_t)n != bpb.bps) {
739 		warnx("%s: can't write sector %u", fname, lsn);
740 		return -1;
741 	    }
742 	}
743     }
744     return 0;
745 }
746 
747 #ifndef MAKEFS
748 /*
749  * return -1 with error if file system is mounted.
750  */
751 static int
752 check_mounted(const char *fname, mode_t mode)
753 {
754     struct statvfs *mp;
755     const char *s1, *s2;
756     size_t len;
757     int n, r;
758 
759     if (!(n = getmntinfo(&mp, MNT_NOWAIT))) {
760 	warn("getmntinfo");
761 	return -1;
762     }
763     len = strlen(_PATH_DEV);
764     s1 = fname;
765     if (!strncmp(s1, _PATH_DEV, len))
766 	s1 += len;
767     r = S_ISCHR(mode) && s1 != fname && *s1 == 'r';
768     for (; n--; mp++) {
769 	s2 = mp->f_mntfromname;
770 	if (!strncmp(s2, _PATH_DEV, len))
771 	    s2 += len;
772 	if ((r && s2 != mp->f_mntfromname && !strcmp(s1 + 1, s2)) ||
773 	    !strcmp(s1, s2)) {
774 	    warnx("%s is mounted on %s", fname, mp->f_mntonname);
775 	    return -1;
776 	}
777     }
778     return 0;
779 }
780 #endif
781 
782 /*
783  * Get a standard format.
784  */
785 static int
786 getstdfmt(const char *fmt, struct bpb *bpb)
787 {
788     u_int x, i;
789 
790     x = sizeof(stdfmt) / sizeof(stdfmt[0]);
791     for (i = 0; i < x && strcmp(fmt, stdfmt[i].name); i++);
792     if (i == x) {
793 	warnx("%s: unknown standard format", fmt);
794 	return -1;
795     }
796     *bpb = stdfmt[i].bpb;
797     return 0;
798 }
799 
800 /*
801  * Get disk slice, partition, and geometry information.
802  */
803 static int
804 getbpbinfo(int fd, const char *fname, const char *dtype, int iflag,
805     struct bpb *bpb, int create)
806 {
807     const char *s1, *s2;
808     int part;
809 
810     part = -1;
811     s1 = fname;
812     if ((s2 = strrchr(s1, '/')))
813 	s1 = s2 + 1;
814     for (s2 = s1; *s2 && !isdigit((unsigned char)*s2); s2++);
815     if (!*s2 || s2 == s1)
816 	s2 = NULL;
817     else
818 	while (isdigit((unsigned char)*++s2));
819     s1 = s2;
820 
821 #ifndef MAKEFS
822     int maxpartitions = getmaxpartitions();
823 
824     // XXX: Does not work with wedges
825     if (s2 && *s2 >= 'a' && *s2 <= 'a' + maxpartitions - 1) {
826 	part = *s2++ - 'a';
827     }
828 #endif
829     if (((part != -1) && ((!iflag && part != -1) || !bpb->bsec)) ||
830 	!bpb->bps || !bpb->spt || !bpb->hds) {
831 	u_int sector_size;
832 	u_int nsectors;
833 	u_int ntracks;
834 	u_int size;
835 #ifndef MAKEFS
836 	struct disk_geom geo;
837 	struct dkwedge_info dkw;
838 
839 	if (!create && getdiskinfo(fname, fd, NULL, &geo, &dkw) != -1) {
840 	    sector_size = geo.dg_secsize = 512;
841 	    nsectors = geo.dg_nsectors = 63;
842 	    ntracks = geo.dg_ntracks = 255;
843 	    size = dkw.dkw_size;
844 	} else
845 #endif
846 	{
847 	    struct stat st;
848 
849 	    if (fstat(fd, &st) == -1) {
850 		warnx("Can't get disk size for `%s'", fname);
851 		return -1;
852 	    }
853 	    /* create a fake geometry for a file image */
854 	    sector_size = 512;
855 	    nsectors = 63;
856 	    ntracks = 255;
857 	    size = st.st_size / sector_size;
858 	}
859 	if (!bpb->bps) {
860 	    if (ckgeom(fname, sector_size, "bytes/sector") == -1)
861 		return -1;
862 	    bpb->bps = sector_size;
863 	}
864 
865 	if (nsectors > 63) {
866 		/*
867 		 * The kernel doesn't accept BPB with spt > 63.
868 		 * (see sys/fs/msdosfs/msdosfs_vfsops.c:msdosfs_mountfs())
869 		 * If values taken from disklabel don't match these
870 		 * restrictions, use popular BIOS default values instead.
871 		 */
872 		nsectors = 63;
873 	}
874 	if (!bpb->spt) {
875 	    if (ckgeom(fname, nsectors, "sectors/track") == -1)
876 		return -1;
877 	    bpb->spt = nsectors;
878 	}
879 	if (!bpb->hds)
880 	    if (ckgeom(fname, ntracks, "drive heads") == -1)
881 		return -1;
882 	    bpb->hds = ntracks;
883 	if (!bpb->bsec)
884 	    bpb->bsec = size;
885     }
886     return 0;
887 }
888 
889 /*
890  * Print out BPB values.
891  */
892 static void
893 print_bpb(struct bpb *bpb)
894 {
895     printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
896 	   bpb->nft);
897     if (bpb->rde)
898 	printf(" rde=%u", bpb->rde);
899     if (bpb->sec)
900 	printf(" sec=%u", bpb->sec);
901     printf(" mid=%#x", bpb->mid);
902     if (bpb->spf)
903 	printf(" spf=%u", bpb->spf);
904     printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
905     if (bpb->bsec)
906 	printf(" bsec=%u", bpb->bsec);
907     if (!bpb->spf) {
908 	printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
909 	printf(" infs=");
910 	printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
911 	printf(" bkbs=");
912 	printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
913     }
914     printf("\n");
915 }
916 
917 /*
918  * Check a disk geometry value.
919  */
920 static int
921 ckgeom(const char *fname, u_int val, const char *msg)
922 {
923     if (!val) {
924 	warnx("%s: no default %s", fname, msg);
925 	return -1;
926     }
927     if (val > MAXU16) {
928 	warnx("%s: illegal %s", fname, msg);
929 	return -1;
930     }
931     return 0;
932 }
933 /*
934  * Check a volume label.
935  */
936 static int
937 oklabel(const char *src)
938 {
939     int c, i;
940 
941     for (i = 0; i <= 11; i++) {
942 	c = (u_char)*src++;
943 	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
944 	    break;
945     }
946     return i && !c;
947 }
948 
949 /*
950  * Make a volume label.
951  */
952 static void
953 mklabel(u_int8_t *dest, const char *src)
954 {
955     int c, i;
956 
957     for (i = 0; i < 11; i++) {
958 	c = *src ? toupper((unsigned char)*src++) : ' ';
959 	*dest++ = !i && c == '\xe5' ? 5 : c;
960     }
961 }
962 
963 /*
964  * Copy string, padding with spaces.
965  */
966 static void
967 setstr(u_int8_t *dest, const char *src, size_t len)
968 {
969     while (len--)
970 	*dest++ = *src ? *src++ : ' ';
971 }
972 
973 static void
974 infohandler(int sig)
975 {
976     got_siginfo = 1;
977 }
978