xref: /minix3/sbin/newfs_msdos/mkfs_msdos.c (revision 4322f20d76933bba96f46b4e10b56aa19f85c1d5)
1 /*	$NetBSD: mkfs_msdos.c,v 1.13 2017/04/14 15:39:29 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 1.13 2017/04/14 15:39:29 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 *, off_t);
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) == -1)
335 	    return -1;
336 	bpb.bsec -= (o.offset / bpb.bps);
337 	if (bpb.spc == 0) {     /* set defaults */
338 	    /* minimum cluster size */
339 	    switch (o.fat_type) {
340 	    case 12:
341 		bpb.spc = 1;            /* use 512 bytes */
342 		x = 2;                  /* up to 2MB */
343 		break;
344 	    case 16:
345 		bpb.spc = 1;            /* use 512 bytes */
346 		x = 32;                 /* up to 32MB */
347 		break;
348 	    default:
349 		bpb.spc = 8;            /* use 4k */
350 		x = 8192;               /* up to 8GB */
351 		break;
352 	    }
353 	    x1 = howmany(bpb.bsec, (1048576 / 512)); /* -> MB */
354 	    while (bpb.spc < 128 && x < x1) {
355 		x *= 2;
356 		bpb.spc *= 2;
357 	    }
358 	}
359     }
360 
361     if (o.volume_label && !oklabel(o.volume_label)) {
362 	warnx("%s: bad volume label", o.volume_label);
363 	return -1;
364     }
365 
366     switch (o.fat_type) {
367     case 0:
368 	if (o.floppy)
369 	    o.fat_type = 12;
370 	else if (!o.directory_entries && (o.info_sector || o.backup_sector))
371 	    o.fat_type = 32;
372 	break;
373     case 12:
374     case 16:
375 	if (o.info_sector) {
376 	    warnx("Cannot specify info sector with FAT%u", o.fat_type);
377 	    return -1;
378 	}
379 	if (o.backup_sector) {
380 	    warnx("Cannot specify backup sector with FAT%u", o.fat_type);
381 	    return -1;
382 	}
383 	break;
384     case 32:
385 	if (o.directory_entries) {
386 	    warnx("Cannot specify directory entries with FAT32");
387 	    return -1;
388 	}
389 	break;
390     default:
391 	warnx("%d: bad FAT type", o.fat_type);
392 	return -1;
393     }
394     if (!powerof2(bpb.bps)) {
395 	warnx("bytes/sector (%u) is not a power of 2", bpb.bps);
396 	return -1;
397     }
398     if (bpb.bps < MINBPS) {
399 	warnx("bytes/sector (%u) is too small; minimum is %u",
400 	     bpb.bps, MINBPS);
401 	return -1;
402     }
403 
404     if (o.floppy && o.fat_type == 32)
405 	bpb.rde = 0;
406     if (o.block_size) {
407 	if (!powerof2(o.block_size)) {
408 	    warnx("block size (%u) is not a power of 2", o.block_size);
409 	    return -1;
410 	}
411 	if (o.block_size < bpb.bps) {
412 	    warnx("block size (%u) is too small; minimum is %u",
413 		o.block_size, bpb.bps);
414 	    return -1;
415 	}
416 	if (o.block_size > bpb.bps * MAXSPC) {
417 	    warnx("block size (%u) is too large; maximum is %u",
418 		o.block_size, bpb.bps * MAXSPC);
419 	    return -1;
420 	}
421 	bpb.spc = o.block_size / bpb.bps;
422     }
423     if (o.sectors_per_cluster) {
424 	if (!powerof2(o.sectors_per_cluster)) {
425 	    warnx("sectors/cluster (%u) is not a power of 2",
426 		o.sectors_per_cluster);
427 	    return -1;
428 	}
429 	bpb.spc = o.sectors_per_cluster;
430     }
431     if (o.reserved_sectors)
432 	bpb.res = o.reserved_sectors;
433     if (o.num_FAT) {
434 	if (o.num_FAT > MAXNFT) {
435 	    warnx("number of FATs (%u) is too large; maximum is %u",
436 		 o.num_FAT, MAXNFT);
437 	    return -1;
438 	}
439 	bpb.nft = o.num_FAT;
440     }
441     if (o.directory_entries)
442 	bpb.rde = o.directory_entries;
443     if (o.media_descriptor_set) {
444 	if (o.media_descriptor < 0xf0) {
445 	    warnx("illegal media descriptor (%#x)", o.media_descriptor);
446 	    return -1;
447 	}
448 	bpb.mid = o.media_descriptor;
449     }
450     if (o.sectors_per_fat)
451 	bpb.bspf = o.sectors_per_fat;
452     if (o.info_sector)
453 	bpb.infs = o.info_sector;
454     if (o.backup_sector)
455 	bpb.bkbs = o.backup_sector;
456     bss = 1;
457     bname = NULL;
458     fd1 = -1;
459     if (o.bootstrap) {
460 	bname = o.bootstrap;
461 	if (!strchr(bname, '/')) {
462 	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
463 	    if (!(bname = strdup(buf))) {
464 		warn(NULL);
465 		return -1;
466 	    }
467 	}
468 	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb)) {
469 	    warn("%s", bname);
470 	    return -1;
471 	}
472 	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bps ||
473 	    sb.st_size < bpb.bps || sb.st_size > bpb.bps * MAXU16) {
474 	    warnx("%s: inappropriate file type or format", bname);
475 	    return -1;
476 	}
477 	bss = sb.st_size / bpb.bps;
478     }
479     if (!bpb.nft)
480 	bpb.nft = 2;
481     if (!o.fat_type) {
482 	if (bpb.bsec < (bpb.res ? bpb.res : bss) +
483 	    howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
484 		    ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
485 	    bpb.nft +
486 	    howmany(bpb.rde ? bpb.rde : DEFRDE,
487 		    bpb.bps / sizeof(struct de)) +
488 	    (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
489 	    (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
490 	    o.fat_type = 12;
491 	else if (bpb.rde || bpb.bsec <
492 		 (bpb.res ? bpb.res : bss) +
493 		 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
494 		 howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
495 		 (MAXCLS16 + 1) *
496 		 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
497 	    o.fat_type = 16;
498 	else
499 	    o.fat_type = 32;
500     }
501     x = bss;
502     if (o.fat_type == 32) {
503 	if (!bpb.infs) {
504 	    if (x == MAXU16 || x == bpb.bkbs) {
505 		warnx("no room for info sector");
506 		return -1;
507 	    }
508 	    bpb.infs = x;
509 	}
510 	if (bpb.infs != MAXU16 && x <= bpb.infs)
511 	    x = bpb.infs + 1;
512 	if (!bpb.bkbs) {
513 	    if (x == MAXU16) {
514 		warnx("no room for backup sector");
515 		return -1;
516 	    }
517 	    bpb.bkbs = x;
518 	} else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs) {
519 	    warnx("backup sector would overwrite info sector");
520 	    return -1;
521 	}
522 	if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
523 	    x = bpb.bkbs + 1;
524     }
525     if (!bpb.res)
526 	bpb.res = o.fat_type == 32 ? MAX(x, MAX(16384 / bpb.bps, 4)) : x;
527     else if (bpb.res < x) {
528 	warnx("too few reserved sectors (need %d have %d)", x, bpb.res);
529 	return -1;
530     }
531     if (o.fat_type != 32 && !bpb.rde)
532 	bpb.rde = DEFRDE;
533     rds = howmany(bpb.rde, bpb.bps / sizeof(struct de));
534     if (!bpb.spc)
535 	for (bpb.spc = howmany(o.fat_type == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
536 	     bpb.spc < MAXSPC &&
537 	     bpb.res +
538 	     howmany((RESFTE + maxcls(o.fat_type)) * (o.fat_type / BPN),
539 		     bpb.bps * NPB) * bpb.nft +
540 	     rds +
541 	     (u_int64_t)(maxcls(o.fat_type) + 1) * bpb.spc <= bpb.bsec;
542 	     bpb.spc <<= 1);
543     if (o.fat_type != 32 && bpb.bspf > MAXU16) {
544 	warnx("too many sectors/FAT for FAT12/16");
545 	return -1;
546     }
547     x1 = bpb.res + rds;
548     x = bpb.bspf ? bpb.bspf : 1;
549     if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec) {
550 	warnx("meta data exceeds file system size");
551 	return -1;
552     }
553     x1 += x * bpb.nft;
554     x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
555 	(bpb.spc * bpb.bps * NPB + o.fat_type / BPN * bpb.nft);
556     x2 = howmany((RESFTE + MIN(x, maxcls(o.fat_type))) * (o.fat_type / BPN),
557 		 bpb.bps * NPB);
558     if (!bpb.bspf) {
559 	bpb.bspf = x2;
560 	x1 += (bpb.bspf - 1) * bpb.nft;
561     }
562     cls = (bpb.bsec - x1) / bpb.spc;
563     x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (o.fat_type / BPN) - RESFTE;
564     if (cls > x)
565 	cls = x;
566     if (bpb.bspf < x2) {
567 	warnx("warning: sectors/FAT limits file system to %u clusters",
568 	      cls);
569 	return -1;
570     }
571     if (cls < mincls(o.fat_type)) {
572 	warnx("%u clusters too few clusters for FAT%u, need %u", cls,
573 	    o.fat_type, mincls(o.fat_type));
574 	return -1;
575     }
576     if (cls > maxcls(o.fat_type)) {
577 	cls = maxcls(o.fat_type);
578 	bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
579 	warnx("warning: FAT type limits file system to %u sectors",
580 	      bpb.bsec);
581 	return -1;
582     }
583     printf("%s: %u sector%s in %u FAT%u cluster%s "
584 	   "(%u bytes/cluster)\n", fname, cls * bpb.spc,
585 	   cls * bpb.spc == 1 ? "" : "s", cls, o.fat_type,
586 	   cls == 1 ? "" : "s", bpb.bps * bpb.spc);
587     if (!bpb.mid)
588 	bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
589     if (o.fat_type == 32)
590 	bpb.rdcl = RESFTE;
591     if (bpb.hid + bpb.bsec <= MAXU16) {
592 	bpb.sec = bpb.bsec;
593 	bpb.bsec = 0;
594     }
595     if (o.fat_type != 32) {
596 	bpb.spf = bpb.bspf;
597 	bpb.bspf = 0;
598     }
599     ch = 0;
600     if (o.fat_type == 12)
601 	ch = 1;			/* 001 Primary DOS with 12 bit FAT */
602     else if (o.fat_type == 16) {
603 	if (bpb.bsec == 0)
604 	    ch = 4;		/* 004 Primary DOS with 16 bit FAT <32M */
605 	else
606 	    ch = 6;		/* 006 Primary 'big' DOS, 16-bit FAT (> 32MB) */
607 				/*
608 				 * XXX: what about:
609 				 * 014 DOS (16-bit FAT) - LBA
610 				 *  ?
611 				 */
612     } else if (o.fat_type == 32) {
613 	ch = 11;		/* 011 Primary DOS with 32 bit FAT */
614 				/*
615 				 * XXX: what about:
616 				 * 012 Primary DOS with 32 bit FAT - LBA
617 				 *  ?
618 				 */
619     }
620     if (ch != 0)
621 	printf("MBR type: %d\n", ch);
622     print_bpb(&bpb);
623     if (!o.no_create) {
624 	if (o.timestamp_set) {
625 		tv.tv_sec = now = o.timestamp;
626 		tv.tv_usec = 0;
627 		tm = gmtime(&now);
628 	} else {
629 		gettimeofday(&tv, NULL);
630 		now = tv.tv_sec;
631 		tm = localtime(&now);
632 	}
633 	if (!(img = malloc(bpb.bps)))
634 	    err(1, NULL);
635 	dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;
636 #ifdef SIGINFO
637 	signal(SIGINFO, infohandler);
638 #endif
639 	for (lsn = 0; lsn < dir + (o.fat_type == 32 ? bpb.spc : rds); lsn++) {
640 	    if (got_siginfo) {
641 		fprintf(stderr,"%s: writing sector %u of %u (%u%%)\n",
642 		    fname,lsn,(dir + (o.fat_type == 32 ? bpb.spc : rds)),
643 		    (lsn*100)/(dir + (o.fat_type == 32 ? bpb.spc : rds)));
644 		got_siginfo = 0;
645 	    }
646 	    x = lsn;
647 	    if (o.bootstrap &&
648 		o.fat_type == 32 && bpb.bkbs != MAXU16 &&
649 		bss <= bpb.bkbs && x >= bpb.bkbs) {
650 		x -= bpb.bkbs;
651 		if (!x && lseek(fd1, o.offset, SEEK_SET)) {
652 		    warn("%s", bname);
653 		    return -1;
654 		}
655 	    }
656 	    if (o.bootstrap && x < bss) {
657 		if ((n = read(fd1, img, bpb.bps)) == -1) {
658 		    warn("%s", bname);
659 		    return -1;
660 		}
661 		if ((size_t)n != bpb.bps) {
662 		    warnx("%s: can't read sector %u", bname, x);
663 		    return -1;
664 		}
665 	    } else
666 		memset(img, 0, bpb.bps);
667 	    if (!lsn ||
668 	      (o.fat_type == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
669 		x1 = sizeof(struct bs);
670 		bsbpb = (struct bsbpb *)(img + x1);
671 		mk2(bsbpb->bps, bpb.bps);
672 		mk1(bsbpb->spc, bpb.spc);
673 		mk2(bsbpb->res, bpb.res);
674 		mk1(bsbpb->nft, bpb.nft);
675 		mk2(bsbpb->rde, bpb.rde);
676 		mk2(bsbpb->sec, bpb.sec);
677 		mk1(bsbpb->mid, bpb.mid);
678 		mk2(bsbpb->spf, bpb.spf);
679 		mk2(bsbpb->spt, bpb.spt);
680 		mk2(bsbpb->hds, bpb.hds);
681 		mk4(bsbpb->hid, bpb.hid);
682 		mk4(bsbpb->bsec, bpb.bsec);
683 		x1 += sizeof(struct bsbpb);
684 		if (o.fat_type == 32) {
685 		    bsxbpb = (struct bsxbpb *)(img + x1);
686 		    mk4(bsxbpb->bspf, bpb.bspf);
687 		    mk2(bsxbpb->xflg, 0);
688 		    mk2(bsxbpb->vers, 0);
689 		    mk4(bsxbpb->rdcl, bpb.rdcl);
690 		    mk2(bsxbpb->infs, bpb.infs);
691 		    mk2(bsxbpb->bkbs, bpb.bkbs);
692 		    x1 += sizeof(struct bsxbpb);
693 		}
694 		bsx = (struct bsx *)(img + x1);
695 		mk1(bsx->sig, 0x29);
696 		if (o.volume_id_set)
697 		    x = o.volume_id;
698 		else
699 		    x = (((u_int)(1 + tm->tm_mon) << 8 |
700 			  (u_int)tm->tm_mday) +
701 			 ((u_int)tm->tm_sec << 8 |
702 			  (u_int)(tv.tv_usec / 10))) << 16 |
703 			((u_int)(1900 + tm->tm_year) +
704 			 ((u_int)tm->tm_hour << 8 |
705 			  (u_int)tm->tm_min));
706 		mk4(bsx->volid, x);
707 		mklabel(bsx->label, o.volume_label ? o.volume_label : "NO NAME");
708 		snprintf(buf, sizeof(buf), "FAT%u", o.fat_type);
709 		setstr(bsx->type, buf, sizeof(bsx->type));
710 		if (!o.bootstrap) {
711 		    x1 += sizeof(struct bsx);
712 		    bs = (struct bs *)img;
713 		    mk1(bs->jmp[0], 0xeb);
714 		    mk1(bs->jmp[1], x1 - 2);
715 		    mk1(bs->jmp[2], 0x90);
716 		    setstr(bs->oem, o.OEM_string ? o.OEM_string : "NetBSD",
717 			   sizeof(bs->oem));
718 		    memcpy(img + x1, bootcode, sizeof(bootcode));
719 		    mk2(img + MINBPS - 2, DOSMAGIC);
720 		}
721 	    } else if (o.fat_type == 32 && bpb.infs != MAXU16 &&
722 		       (lsn == bpb.infs ||
723 			(bpb.bkbs != MAXU16 &&
724 			 lsn == bpb.bkbs + bpb.infs))) {
725 		mk4(img, 0x41615252);
726 		mk4(img + MINBPS - 28, 0x61417272);
727 		mk4(img + MINBPS - 24, 0xffffffff);
728 		mk4(img + MINBPS - 20, 0xffffffff);
729 		mk2(img + MINBPS - 2, DOSMAGIC);
730 	    } else if (lsn >= bpb.res && lsn < dir &&
731 		       !((lsn - bpb.res) %
732 			 (bpb.spf ? bpb.spf : bpb.bspf))) {
733 		mk1(img[0], bpb.mid);
734 		for (x = 1; x < o.fat_type * (o.fat_type == 32 ? 3U : 2U) / 8U; x++)
735 		    mk1(img[x], o.fat_type == 32 && x % 4 == 3 ? 0x0f : 0xff);
736 	    } else if (lsn == dir && o.volume_label) {
737 		de = (struct de *)img;
738 		mklabel(de->namext, o.volume_label);
739 		mk1(de->attr, 050);
740 		x = (u_int)tm->tm_hour << 11 |
741 		    (u_int)tm->tm_min << 5 |
742 		    (u_int)tm->tm_sec >> 1;
743 		mk2(de->time, x);
744 		x = (u_int)(tm->tm_year - 80) << 9 |
745 		    (u_int)(tm->tm_mon + 1) << 5 |
746 		    (u_int)tm->tm_mday;
747 		mk2(de->date, x);
748 	    }
749 	    if ((n = write(fd, img, bpb.bps)) == -1) {
750 		warn("%s", fname);
751 		return -1;
752 	    }
753 	    if ((size_t)n != bpb.bps) {
754 		warnx("%s: can't write sector %u", fname, lsn);
755 		return -1;
756 	    }
757 	}
758     }
759     return 0;
760 }
761 
762 #ifndef MAKEFS
763 /*
764  * return -1 with error if file system is mounted.
765  */
766 static int
767 check_mounted(const char *fname, mode_t mode)
768 {
769     struct statvfs *mp;
770     const char *s1, *s2;
771     size_t len;
772     int n, r;
773 
774     if (!(n = getmntinfo(&mp, MNT_NOWAIT))) {
775 	warn("getmntinfo");
776 	return -1;
777     }
778     len = strlen(_PATH_DEV);
779     s1 = fname;
780     if (!strncmp(s1, _PATH_DEV, len))
781 	s1 += len;
782     r = S_ISCHR(mode) && s1 != fname && *s1 == 'r';
783     for (; n--; mp++) {
784 	s2 = mp->f_mntfromname;
785 	if (!strncmp(s2, _PATH_DEV, len))
786 	    s2 += len;
787 	if ((r && s2 != mp->f_mntfromname && !strcmp(s1 + 1, s2)) ||
788 	    !strcmp(s1, s2)) {
789 	    warnx("%s is mounted on %s", fname, mp->f_mntonname);
790 	    return -1;
791 	}
792     }
793     return 0;
794 }
795 #endif
796 
797 /*
798  * Get a standard format.
799  */
800 static int
801 getstdfmt(const char *fmt, struct bpb *bpb)
802 {
803     u_int x, i;
804 
805     x = sizeof(stdfmt) / sizeof(stdfmt[0]);
806     for (i = 0; i < x && strcmp(fmt, stdfmt[i].name); i++);
807     if (i == x) {
808 	warnx("%s: unknown standard format", fmt);
809 	return -1;
810     }
811     *bpb = stdfmt[i].bpb;
812     return 0;
813 }
814 
815 /*
816  * Get disk slice, partition, and geometry information.
817  */
818 static int
819 getbpbinfo(int fd, const char *fname, const char *dtype, int iflag,
820     struct bpb *bpb, off_t create_size)
821 {
822     const char *s1, *s2;
823     int part;
824 
825     part = -1;
826     s1 = fname;
827     if ((s2 = strrchr(s1, '/')))
828 	s1 = s2 + 1;
829     for (s2 = s1; *s2 && !isdigit((unsigned char)*s2); s2++);
830     if (!*s2 || s2 == s1)
831 	s2 = NULL;
832     else
833 	while (isdigit((unsigned char)*++s2));
834     s1 = s2;
835 
836 #ifndef MAKEFS
837     int maxpartitions = getmaxpartitions();
838     struct disk_geom geo;
839     struct dkwedge_info dkw;
840 
841     // XXX: Does not work with wedges
842     if (s2 && *s2 >= 'a' && *s2 <= 'a' + maxpartitions - 1) {
843 	part = *s2++ - 'a';
844     }
845 #endif
846 
847     if (!(((part != -1) && ((!iflag && part != -1) || !bpb->bsec)) ||
848 	!bpb->bps || !bpb->spt || !bpb->hds)) {
849 	return 0;
850     }
851 
852     u_int sector_size = 512;
853     u_int nsectors = 63;
854     u_int ntracks = 255;
855     u_int size;
856 
857     if (create_size == 0) {
858 #ifndef MAKEFS
859 	if (getdiskinfo(fname, fd, NULL, &geo, &dkw) != -1) {
860 	    sector_size = geo.dg_secsize;
861 	    nsectors = geo.dg_nsectors;
862 	    ntracks = geo.dg_ntracks;
863 	    size = dkw.dkw_size;
864 	} else
865 #endif
866 	{
867 	    struct stat st;
868 
869 	    if (fstat(fd, &st) == -1) {
870 		warnx("Can't get disk size for `%s'", fname);
871 		return -1;
872 	    }
873 	    size = st.st_size / sector_size;
874 	}
875     } else {
876 	size = create_size / sector_size;
877     }
878 
879     if (!bpb->bps) {
880 	if (ckgeom(fname, sector_size, "bytes/sector") == -1)
881 	    return -1;
882 	bpb->bps = sector_size;
883     }
884 
885     if (nsectors > 63) {
886 	    /*
887 	     * The kernel doesn't accept BPB with spt > 63.
888 	     * (see sys/fs/msdosfs/msdosfs_vfsops.c:msdosfs_mountfs())
889 	     * If values taken from disklabel don't match these
890 	     * restrictions, use popular BIOS default values instead.
891 	     */
892 	    nsectors = 63;
893     }
894     if (!bpb->spt) {
895 	if (ckgeom(fname, nsectors, "sectors/track") == -1)
896 	    return -1;
897 	bpb->spt = nsectors;
898     }
899     if (!bpb->hds)
900 	if (ckgeom(fname, ntracks, "drive heads") == -1)
901 	    return -1;
902 	bpb->hds = ntracks;
903     if (!bpb->bsec)
904 	bpb->bsec = size;
905 
906     return 0;
907 }
908 
909 /*
910  * Print out BPB values.
911  */
912 static void
913 print_bpb(struct bpb *bpb)
914 {
915     printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
916 	   bpb->nft);
917     if (bpb->rde)
918 	printf(" rde=%u", bpb->rde);
919     if (bpb->sec)
920 	printf(" sec=%u", bpb->sec);
921     printf(" mid=%#x", bpb->mid);
922     if (bpb->spf)
923 	printf(" spf=%u", bpb->spf);
924     printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
925     if (bpb->bsec)
926 	printf(" bsec=%u", bpb->bsec);
927     if (!bpb->spf) {
928 	printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
929 	printf(" infs=");
930 	printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
931 	printf(" bkbs=");
932 	printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
933     }
934     printf("\n");
935 }
936 
937 /*
938  * Check a disk geometry value.
939  */
940 static int
941 ckgeom(const char *fname, u_int val, const char *msg)
942 {
943     if (!val) {
944 	warnx("%s: no default %s", fname, msg);
945 	return -1;
946     }
947     if (val > MAXU16) {
948 	warnx("%s: illegal %s", fname, msg);
949 	return -1;
950     }
951     return 0;
952 }
953 /*
954  * Check a volume label.
955  */
956 static int
957 oklabel(const char *src)
958 {
959     int c, i;
960 
961     for (i = 0; i <= 11; i++) {
962 	c = (u_char)*src++;
963 	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
964 	    break;
965     }
966     return i && !c;
967 }
968 
969 /*
970  * Make a volume label.
971  */
972 static void
973 mklabel(u_int8_t *dest, const char *src)
974 {
975     int c, i;
976 
977     for (i = 0; i < 11; i++) {
978 	c = *src ? toupper((unsigned char)*src++) : ' ';
979 	*dest++ = !i && c == '\xe5' ? 5 : c;
980     }
981 }
982 
983 /*
984  * Copy string, padding with spaces.
985  */
986 static void
987 setstr(u_int8_t *dest, const char *src, size_t len)
988 {
989     while (len--)
990 	*dest++ = *src ? *src++ : ' ';
991 }
992 
993 static void
994 infohandler(int sig)
995 {
996     got_siginfo = 1;
997 }
998