newfs_msdos.c revision 59215
1/*
2 * Copyright (c) 1998 Robert Nordier
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY
19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
21 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
23 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
25 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#ifndef lint
29static const char rcsid[] =
30  "$FreeBSD: head/sbin/newfs_msdos/newfs_msdos.c 59215 2000-04-14 06:10:01Z imp $";
31#endif /* not lint */
32
33#include <sys/param.h>
34#include <sys/stat.h>
35#include <sys/diskslice.h>
36#include <sys/disklabel.h>
37#include <sys/mount.h>
38
39#include <ctype.h>
40#include <err.h>
41#include <errno.h>
42#include <fcntl.h>
43#include <paths.h>
44#include <stdio.h>
45#include <stdlib.h>
46#include <string.h>
47#include <unistd.h>
48
49#define MAXU16	  0xffff	/* maximum unsigned 16-bit quantity */
50#define BPN	  4		/* bits per nibble */
51#define NPB	  2		/* nibbles per byte */
52
53#define DOSMAGIC  0xaa55	/* DOS magic number */
54#define MINBPS	  128		/* minimum bytes per sector */
55#define MAXSPC	  128		/* maximum sectors per cluster */
56#define MAXNFT	  16		/* maximum number of FATs */
57#define DEFBLK	  4096		/* default block size */
58#define DEFBLK16  2048		/* default block size FAT16 */
59#define DEFRDE	  512		/* default root directory entries */
60#define RESFTE	  2		/* reserved FAT entries */
61#define MINCLS12  1		/* minimum FAT12 clusters */
62#define MINCLS16  0x1000	/* minimum FAT16 clusters */
63#define MINCLS32  2		/* minimum FAT32 clusters */
64#define MAXCLS12  0xfed 	/* maximum FAT12 clusters */
65#define MAXCLS16  0xfff5	/* maximum FAT16 clusters */
66#define MAXCLS32  0xffffff5	/* maximum FAT32 clusters */
67
68#define mincls(fat)  ((fat) == 12 ? MINCLS12 :	\
69		      (fat) == 16 ? MINCLS16 :	\
70				    MINCLS32)
71
72#define maxcls(fat)  ((fat) == 12 ? MAXCLS12 :	\
73		      (fat) == 16 ? MAXCLS16 :	\
74				    MAXCLS32)
75
76#define mk1(p, x)				\
77    (p) = (u_int8_t)(x)
78
79#define mk2(p, x)				\
80    (p)[0] = (u_int8_t)(x),			\
81    (p)[1] = (u_int8_t)((x) >> 010)
82
83#define mk4(p, x)				\
84    (p)[0] = (u_int8_t)(x),			\
85    (p)[1] = (u_int8_t)((x) >> 010),		\
86    (p)[2] = (u_int8_t)((x) >> 020),		\
87    (p)[3] = (u_int8_t)((x) >> 030)
88
89#define argto1(arg, lo, msg)  argtou(arg, lo, 0xff, msg)
90#define argto2(arg, lo, msg)  argtou(arg, lo, 0xffff, msg)
91#define argto4(arg, lo, msg)  argtou(arg, lo, 0xffffffff, msg)
92#define argtox(arg, lo, msg)  argtou(arg, lo, UINT_MAX, msg)
93
94struct bs {
95    u_int8_t jmp[3];		/* bootstrap entry point */
96    u_int8_t oem[8];		/* OEM name and version */
97};
98
99struct bsbpb {
100    u_int8_t bps[2];		/* bytes per sector */
101    u_int8_t spc;		/* sectors per cluster */
102    u_int8_t res[2];		/* reserved sectors */
103    u_int8_t nft;		/* number of FATs */
104    u_int8_t rde[2];		/* root directory entries */
105    u_int8_t sec[2];		/* total sectors */
106    u_int8_t mid;		/* media descriptor */
107    u_int8_t spf[2];		/* sectors per FAT */
108    u_int8_t spt[2];		/* sectors per track */
109    u_int8_t hds[2];		/* drive heads */
110    u_int8_t hid[4];		/* hidden sectors */
111    u_int8_t bsec[4];		/* big total sectors */
112};
113
114struct bsxbpb {
115    u_int8_t bspf[4];		/* big sectors per FAT */
116    u_int8_t xflg[2];		/* FAT control flags */
117    u_int8_t vers[2];		/* file system version */
118    u_int8_t rdcl[4];		/* root directory start cluster */
119    u_int8_t infs[2];		/* file system info sector */
120    u_int8_t bkbs[2];		/* backup boot sector */
121    u_int8_t rsvd[12];		/* reserved */
122};
123
124struct bsx {
125    u_int8_t drv;		/* drive number */
126    u_int8_t rsvd;		/* reserved */
127    u_int8_t sig;		/* extended boot signature */
128    u_int8_t volid[4];		/* volume ID number */
129    u_int8_t label[11]; 	/* volume label */
130    u_int8_t type[8];		/* file system type */
131};
132
133struct de {
134    u_int8_t namext[11];	/* name and extension */
135    u_int8_t attr;		/* attributes */
136    u_int8_t rsvd[10];		/* reserved */
137    u_int8_t time[2];		/* creation time */
138    u_int8_t date[2];		/* creation date */
139    u_int8_t clus[2];		/* starting cluster */
140    u_int8_t size[4];		/* size */
141};
142
143struct bpb {
144    u_int bps;			/* bytes per sector */
145    u_int spc;			/* sectors per cluster */
146    u_int res;			/* reserved sectors */
147    u_int nft;			/* number of FATs */
148    u_int rde;			/* root directory entries */
149    u_int sec;			/* total sectors */
150    u_int mid;			/* media descriptor */
151    u_int spf;			/* sectors per FAT */
152    u_int spt;			/* sectors per track */
153    u_int hds;			/* drive heads */
154    u_int hid;			/* hidden sectors */
155    u_int bsec; 		/* big total sectors */
156    u_int bspf; 		/* big sectors per FAT */
157    u_int rdcl; 		/* root directory start cluster */
158    u_int infs; 		/* file system info sector */
159    u_int bkbs; 		/* backup boot sector */
160};
161
162static struct {
163    const char *name;
164    struct bpb bpb;
165} stdfmt[] = {
166    {"160",  {512, 1, 1, 2,  64,  320, 0xfe, 1,  8, 1}},
167    {"180",  {512, 1, 1, 2,  64,  360, 0xfc, 2,  9, 1}},
168    {"320",  {512, 2, 1, 2, 112,  640, 0xff, 1,  8, 2}},
169    {"360",  {512, 2, 1, 2, 112,  720, 0xfd, 2,  9, 2}},
170    {"640",  {512, 2, 1, 2, 112, 1280, 0xfb, 2,  8, 2}},
171    {"720",  {512, 2, 1, 2, 112, 1440, 0xf9, 3,  9, 2}},
172    {"1200", {512, 1, 1, 2, 224, 2400, 0xf9, 7, 15, 2}},
173    {"1232", {1024,1, 1, 2, 192, 1232, 0xfe, 2,  8, 2}},
174    {"1440", {512, 1, 1, 2, 224, 2880, 0xf0, 9, 18, 2}},
175    {"2880", {512, 2, 1, 2, 240, 5760, 0xf0, 9, 36, 2}}
176};
177
178static u_int8_t bootcode[] = {
179    0xfa,			/* cli		    */
180    0x31, 0xc0, 		/* xor	   ax,ax    */
181    0x8e, 0xd0, 		/* mov	   ss,ax    */
182    0xbc, 0x00, 0x7c,		/* mov	   sp,7c00h */
183    0xfb,			/* sti		    */
184    0x8e, 0xd8, 		/* mov	   ds,ax    */
185    0xe8, 0x00, 0x00,		/* call    $ + 3    */
186    0x5e,			/* pop	   si	    */
187    0x83, 0xc6, 0x19,		/* add	   si,+19h  */
188    0xbb, 0x07, 0x00,		/* mov	   bx,0007h */
189    0xfc,			/* cld		    */
190    0xac,			/* lodsb	    */
191    0x84, 0xc0, 		/* test    al,al    */
192    0x74, 0x06, 		/* jz	   $ + 8    */
193    0xb4, 0x0e, 		/* mov	   ah,0eh   */
194    0xcd, 0x10, 		/* int	   10h	    */
195    0xeb, 0xf5, 		/* jmp	   $ - 9    */
196    0x30, 0xe4, 		/* xor	   ah,ah    */
197    0xcd, 0x16, 		/* int	   16h	    */
198    0xcd, 0x19, 		/* int	   19h	    */
199    0x0d, 0x0a,
200    'N', 'o', 'n', '-', 's', 'y', 's', 't',
201    'e', 'm', ' ', 'd', 'i', 's', 'k',
202    0x0d, 0x0a,
203    'P', 'r', 'e', 's', 's', ' ', 'a', 'n',
204    'y', ' ', 'k', 'e', 'y', ' ', 't', 'o',
205    ' ', 'r', 'e', 'b', 'o', 'o', 't',
206    0x0d, 0x0a,
207    0
208};
209
210static void check_mounted(const char *, mode_t);
211static void getstdfmt(const char *, struct bpb *);
212static void getdiskinfo(int, const char *, const char *, int,
213			struct bpb *);
214static void print_bpb(struct bpb *);
215static u_int ckgeom(const char *, u_int, const char *);
216static u_int argtou(const char *, u_int, u_int, const char *);
217static int oklabel(const char *);
218static void mklabel(u_int8_t *, const char *);
219static void setstr(u_int8_t *, const char *, size_t);
220static void usage(void);
221
222/*
223 * Construct a FAT12, FAT16, or FAT32 file system.
224 */
225int
226main(int argc, char *argv[])
227{
228    static char opts[] = "NB:F:I:L:O:S:a:b:c:e:f:h:i:k:m:n:o:r:s:u:";
229    static const char *opt_B, *opt_L, *opt_O, *opt_f;
230    static u_int opt_F, opt_I, opt_S, opt_a, opt_b, opt_c, opt_e;
231    static u_int opt_h, opt_i, opt_k, opt_m, opt_n, opt_o, opt_r;
232    static u_int opt_s, opt_u;
233    static int opt_N;
234    static int Iflag, mflag, oflag;
235    char buf[MAXPATHLEN];
236    struct stat sb;
237    struct timeval tv;
238    struct bpb bpb;
239    struct tm *tm;
240    struct bs *bs;
241    struct bsbpb *bsbpb;
242    struct bsxbpb *bsxbpb;
243    struct bsx *bsx;
244    struct de *de;
245    u_int8_t *img;
246    const char *fname, *dtype, *bname;
247    ssize_t n;
248    time_t now;
249    u_int fat, bss, rds, cls, dir, lsn, x, x1, x2;
250    int ch, fd, fd1;
251
252    while ((ch = getopt(argc, argv, opts)) != -1)
253	switch (ch) {
254	case 'N':
255	    opt_N = 1;
256	    break;
257	case 'B':
258	    opt_B = optarg;
259	    break;
260	case 'F':
261	    if (strcmp(optarg, "12") &&
262		strcmp(optarg, "16") &&
263		strcmp(optarg, "32"))
264		errx(1, "%s: bad FAT type", optarg);
265	    opt_F = atoi(optarg);
266	    break;
267	case 'I':
268	    opt_I = argto4(optarg, 0, "volume ID");
269	    Iflag = 1;
270	    break;
271	case 'L':
272	    if (!oklabel(optarg))
273		errx(1, "%s: bad volume label", optarg);
274	    opt_L = optarg;
275	    break;
276	case 'O':
277	    if (strlen(optarg) > 8)
278		errx(1, "%s: bad OEM string", optarg);
279	    opt_O = optarg;
280	    break;
281	case 'S':
282	    opt_S = argto2(optarg, 1, "bytes/sector");
283	    break;
284	case 'a':
285	    opt_a = argto4(optarg, 1, "sectors/FAT");
286	    break;
287	case 'b':
288	    opt_b = argtox(optarg, 1, "block size");
289	    opt_c = 0;
290	    break;
291	case 'c':
292	    opt_c = argto1(optarg, 1, "sectors/cluster");
293	    opt_b = 0;
294	    break;
295	case 'e':
296	    opt_e = argto2(optarg, 1, "directory entries");
297	    break;
298	case 'f':
299	    opt_f = optarg;
300	    break;
301	case 'h':
302	    opt_h = argto2(optarg, 1, "drive heads");
303	    break;
304	case 'i':
305	    opt_i = argto2(optarg, 1, "info sector");
306	    break;
307	case 'k':
308	    opt_k = argto2(optarg, 1, "backup sector");
309	    break;
310	case 'm':
311	    opt_m = argto1(optarg, 0, "media descriptor");
312	    mflag = 1;
313	    break;
314	case 'n':
315	    opt_n = argto1(optarg, 1, "number of FATs");
316	    break;
317	case 'o':
318	    opt_o = argto4(optarg, 0, "hidden sectors");
319	    oflag = 1;
320	    break;
321	case 'r':
322	    opt_r = argto2(optarg, 1, "reserved sectors");
323	    break;
324	case 's':
325	    opt_s = argto4(optarg, 1, "file system size");
326	    break;
327	case 'u':
328	    opt_u = argto2(optarg, 1, "sectors/track");
329	    break;
330	default:
331	    usage();
332	}
333    argc -= optind;
334    argv += optind;
335    if (argc < 1 || argc > 2)
336	usage();
337    fname = *argv++;
338    if (!strchr(fname, '/')) {
339	snprintf(buf, sizeof(buf), "%sr%s", _PATH_DEV, fname);
340	if (stat(buf, &sb))
341	    snprintf(buf, sizeof(buf), "%s%s", _PATH_DEV, fname);
342	if (!(fname = strdup(buf)))
343	    err(1, NULL);
344    }
345    dtype = *argv;
346    if ((fd = open(fname, opt_N ? O_RDONLY : O_RDWR)) == -1 ||
347	fstat(fd, &sb))
348	err(1, "%s", fname);
349    if (!opt_N)
350	check_mounted(fname, sb.st_mode);
351    if (!S_ISCHR(sb.st_mode))
352	warnx("warning: %s is not a character device", fname);
353    memset(&bpb, 0, sizeof(bpb));
354    if (opt_f) {
355	getstdfmt(opt_f, &bpb);
356	bpb.bsec = bpb.sec;
357	bpb.sec = 0;
358	bpb.bspf = bpb.spf;
359	bpb.spf = 0;
360    }
361    if (opt_h)
362	bpb.hds = opt_h;
363    if (opt_u)
364	bpb.spt = opt_u;
365    if (opt_S)
366	bpb.bps = opt_S;
367    if (opt_s)
368	bpb.bsec = opt_s;
369    if (oflag)
370	bpb.hid = opt_o;
371    if (!(opt_f || (opt_h && opt_u && opt_S && opt_s && oflag)))
372	getdiskinfo(fd, fname, dtype, oflag, &bpb);
373    if (!powerof2(bpb.bps))
374	errx(1, "bytes/sector (%u) is not a power of 2", bpb.bps);
375    if (bpb.bps < MINBPS)
376	errx(1, "bytes/sector (%u) is too small; minimum is %u",
377	     bpb.bps, MINBPS);
378    if (!(fat = opt_F)) {
379	if (opt_f)
380	    fat = 12;
381	else if (!opt_e && (opt_i || opt_k))
382	    fat = 32;
383    }
384    if ((fat == 32 && opt_e) || (fat != 32 && (opt_i || opt_k)))
385	errx(1, "-%c is not a legal FAT%s option",
386	     fat == 32 ? 'e' : opt_i ? 'i' : 'k',
387	     fat == 32 ? "32" : "12/16");
388    if (opt_f && fat == 32)
389	bpb.rde = 0;
390    if (opt_b) {
391	if (!powerof2(opt_b))
392	    errx(1, "block size (%u) is not a power of 2", opt_b);
393	if (opt_b < bpb.bps)
394	    errx(1, "block size (%u) is too small; minimum is %u",
395		 opt_b, bpb.bps);
396	if (opt_b > bpb.bps * MAXSPC)
397	    errx(1, "block size (%u) is too large; maximum is %u",
398		 opt_b, bpb.bps * MAXSPC);
399	bpb.spc = opt_b / bpb.bps;
400    }
401    if (opt_c) {
402	if (!powerof2(opt_c))
403	    errx(1, "sectors/cluster (%u) is not a power of 2", opt_c);
404	bpb.spc = opt_c;
405    }
406    if (opt_r)
407	bpb.res = opt_r;
408    if (opt_n) {
409	if (opt_n > MAXNFT)
410	    errx(1, "number of FATs (%u) is too large; maximum is %u",
411		 opt_n, MAXNFT);
412	bpb.nft = opt_n;
413    }
414    if (opt_e)
415	bpb.rde = opt_e;
416    if (mflag) {
417	if (opt_m < 0xf0)
418	    errx(1, "illegal media descriptor (%#x)", opt_m);
419	bpb.mid = opt_m;
420    }
421    if (opt_a)
422	bpb.bspf = opt_a;
423    if (opt_i)
424	bpb.infs = opt_i;
425    if (opt_k)
426	bpb.bkbs = opt_k;
427    bss = 1;
428    bname = NULL;
429    fd1 = -1;
430    if (opt_B) {
431	bname = opt_B;
432	if (!strchr(bname, '/')) {
433	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
434	    if (!(bname = strdup(buf)))
435		err(1, NULL);
436	}
437	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb))
438	    err(1, "%s", bname);
439	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bps ||
440	    sb.st_size < bpb.bps || sb.st_size > bpb.bps * MAXU16)
441	    errx(1, "%s: inappropriate file type or format", bname);
442	bss = sb.st_size / bpb.bps;
443    }
444    if (!bpb.nft)
445	bpb.nft = 2;
446    if (!fat) {
447	if (bpb.bsec < (bpb.res ? bpb.res : bss) +
448	    howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
449		    ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
450	    bpb.nft +
451	    howmany(bpb.rde ? bpb.rde : DEFRDE,
452		    bpb.bps / sizeof(struct de)) +
453	    (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
454	    (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
455	    fat = 12;
456	else if (bpb.rde || bpb.bsec <
457		 (bpb.res ? bpb.res : bss) +
458		 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
459		 howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
460		 (MAXCLS16 + 1) *
461		 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
462	    fat = 16;
463	else
464	    fat = 32;
465    }
466    x = bss;
467    if (fat == 32) {
468	if (!bpb.infs) {
469	    if (x == MAXU16 || x == bpb.bkbs)
470		errx(1, "no room for info sector");
471	    bpb.infs = x;
472	}
473	if (bpb.infs != MAXU16 && x <= bpb.infs)
474	    x = bpb.infs + 1;
475	if (!bpb.bkbs) {
476	    if (x == MAXU16)
477		errx(1, "no room for backup sector");
478	    bpb.bkbs = x;
479	} else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs)
480	    errx(1, "backup sector would overwrite info sector");
481	if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
482	    x = bpb.bkbs + 1;
483    }
484    if (!bpb.res)
485	bpb.res = fat == 32 ? MAX(x, MAX(16384 / bpb.bps, 4)) : x;
486    else if (bpb.res < x)
487	errx(1, "too few reserved sectors");
488    if (fat != 32 && !bpb.rde)
489	bpb.rde = DEFRDE;
490    rds = howmany(bpb.rde, bpb.bps / sizeof(struct de));
491    if (!bpb.spc)
492	for (bpb.spc = howmany(fat == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
493	     bpb.spc < MAXSPC &&
494	     bpb.res +
495	     howmany((RESFTE + maxcls(fat)) * (fat / BPN),
496		     bpb.bps * NPB) * bpb.nft +
497	     rds +
498	     (u_int64_t)(maxcls(fat) + 1) * bpb.spc <= bpb.bsec;
499	     bpb.spc <<= 1);
500    if (fat != 32 && bpb.bspf > MAXU16)
501	errx(1, "too many sectors/FAT for FAT12/16");
502    x1 = bpb.res + rds;
503    x = bpb.bspf ? bpb.bspf : 1;
504    if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec)
505	errx(1, "meta data exceeds file system size");
506    x1 += x * bpb.nft;
507    x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
508	(bpb.spc * bpb.bps * NPB + fat / BPN * bpb.nft);
509    x2 = howmany((RESFTE + MIN(x, maxcls(fat))) * (fat / BPN),
510		 bpb.bps * NPB);
511    if (!bpb.bspf) {
512	bpb.bspf = x2;
513	x1 += (bpb.bspf - 1) * bpb.nft;
514    }
515    cls = (bpb.bsec - x1) / bpb.spc;
516    x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (fat / BPN) - RESFTE;
517    if (cls > x)
518	cls = x;
519    if (bpb.bspf < x2)
520	warnx("warning: sectors/FAT limits file system to %u clusters",
521	      cls);
522    if (cls < mincls(fat))
523	errx(1, "%u clusters too few clusters for FAT%u, need %u", cls, fat,
524	    mincls(fat));
525    if (cls > maxcls(fat)) {
526	cls = maxcls(fat);
527	bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
528	warnx("warning: FAT type limits file system to %u sectors",
529	      bpb.bsec);
530    }
531    printf("%s: %u sector%s in %u FAT%u cluster%s "
532	   "(%u bytes/cluster)\n", fname, cls * bpb.spc,
533	   cls * bpb.spc == 1 ? "" : "s", cls, fat,
534	   cls == 1 ? "" : "s", bpb.bps * bpb.spc);
535    if (!bpb.mid)
536	bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
537    if (fat == 32)
538	bpb.rdcl = RESFTE;
539    if (bpb.hid + bpb.bsec <= MAXU16) {
540	bpb.sec = bpb.bsec;
541	bpb.bsec = 0;
542    }
543    if (fat != 32) {
544	bpb.spf = bpb.bspf;
545	bpb.bspf = 0;
546    }
547    print_bpb(&bpb);
548    if (!opt_N) {
549	gettimeofday(&tv, NULL);
550	now = tv.tv_sec;
551	tm = localtime(&now);
552	if (!(img = malloc(bpb.bps)))
553	    err(1, NULL);
554	dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;
555	for (lsn = 0; lsn < dir + (fat == 32 ? bpb.spc : rds); lsn++) {
556	    x = lsn;
557	    if (opt_B &&
558		fat == 32 && bpb.bkbs != MAXU16 &&
559		bss <= bpb.bkbs && x >= bpb.bkbs) {
560		x -= bpb.bkbs;
561		if (!x && lseek(fd1, 0, SEEK_SET))
562		    err(1, "%s", bname);
563	    }
564	    if (opt_B && x < bss) {
565		if ((n = read(fd1, img, bpb.bps)) == -1)
566		    err(1, "%s", bname);
567		if (n != bpb.bps)
568		    errx(1, "%s: can't read sector %u", bname, x);
569	    } else
570		memset(img, 0, bpb.bps);
571	    if (!lsn ||
572	      (fat == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
573		x1 = sizeof(struct bs);
574		bsbpb = (struct bsbpb *)(img + x1);
575		mk2(bsbpb->bps, bpb.bps);
576		mk1(bsbpb->spc, bpb.spc);
577		mk2(bsbpb->res, bpb.res);
578		mk1(bsbpb->nft, bpb.nft);
579		mk2(bsbpb->rde, bpb.rde);
580		mk2(bsbpb->sec, bpb.sec);
581		mk1(bsbpb->mid, bpb.mid);
582		mk2(bsbpb->spf, bpb.spf);
583		mk2(bsbpb->spt, bpb.spt);
584		mk2(bsbpb->hds, bpb.hds);
585		mk4(bsbpb->hid, bpb.hid);
586		mk4(bsbpb->bsec, bpb.bsec);
587		x1 += sizeof(struct bsbpb);
588		if (fat == 32) {
589		    bsxbpb = (struct bsxbpb *)(img + x1);
590		    mk4(bsxbpb->bspf, bpb.bspf);
591		    mk2(bsxbpb->xflg, 0);
592		    mk2(bsxbpb->vers, 0);
593		    mk4(bsxbpb->rdcl, bpb.rdcl);
594		    mk2(bsxbpb->infs, bpb.infs);
595		    mk2(bsxbpb->bkbs, bpb.bkbs);
596		    x1 += sizeof(struct bsxbpb);
597		}
598		bsx = (struct bsx *)(img + x1);
599		mk1(bsx->sig, 0x29);
600		if (Iflag)
601		    x = opt_I;
602		else
603		    x = (((u_int)(1 + tm->tm_mon) << 8 |
604			  (u_int)tm->tm_mday) +
605			 ((u_int)tm->tm_sec << 8 |
606			  (u_int)(tv.tv_usec / 10))) << 16 |
607			((u_int)(1900 + tm->tm_year) +
608			 ((u_int)tm->tm_hour << 8 |
609			  (u_int)tm->tm_min));
610		mk4(bsx->volid, x);
611		mklabel(bsx->label, opt_L ? opt_L : "NO NAME");
612		sprintf(buf, "FAT%u", fat);
613		setstr(bsx->type, buf, sizeof(bsx->type));
614		if (!opt_B) {
615		    x1 += sizeof(struct bsx);
616		    bs = (struct bs *)img;
617		    mk1(bs->jmp[0], 0xeb);
618		    mk1(bs->jmp[1], x1 - 2);
619		    mk1(bs->jmp[2], 0x90);
620		    setstr(bs->oem, opt_O ? opt_O : "BSD  4.4",
621			   sizeof(bs->oem));
622		    memcpy(img + x1, bootcode, sizeof(bootcode));
623		    mk2(img + bpb.bps - 2, DOSMAGIC);
624		}
625	    } else if (fat == 32 && bpb.infs != MAXU16 &&
626		       (lsn == bpb.infs ||
627			(bpb.bkbs != MAXU16 &&
628			 lsn == bpb.bkbs + bpb.infs))) {
629		mk4(img, 0x41615252);
630		mk4(img + bpb.bps - 28, 0x61417272);
631		mk4(img + bpb.bps - 24, 0xffffffff);
632		mk4(img + bpb.bps - 20, bpb.rdcl);
633		mk2(img + bpb.bps - 2, DOSMAGIC);
634	    } else if (lsn >= bpb.res && lsn < dir &&
635		       !((lsn - bpb.res) %
636			 (bpb.spf ? bpb.spf : bpb.bspf))) {
637		mk1(img[0], bpb.mid);
638		for (x = 1; x < fat * (fat == 32 ? 3 : 2) / 8; x++)
639		    mk1(img[x], fat == 32 && x % 4 == 3 ? 0x0f : 0xff);
640	    } else if (lsn == dir && opt_L) {
641		de = (struct de *)img;
642		mklabel(de->namext, opt_L);
643		mk1(de->attr, 050);
644		x = (u_int)tm->tm_hour << 11 |
645		    (u_int)tm->tm_min << 5 |
646		    (u_int)tm->tm_sec >> 1;
647		mk2(de->time, x);
648		x = (u_int)(tm->tm_year - 80) << 9 |
649		    (u_int)(tm->tm_mon + 1) << 5 |
650		    (u_int)tm->tm_mday;
651		mk2(de->date, x);
652	    }
653	    if ((n = write(fd, img, bpb.bps)) == -1)
654		err(1, "%s", fname);
655	    if (n != bpb.bps)
656		errx(1, "%s: can't write sector %u", fname, lsn);
657	}
658    }
659    return 0;
660}
661
662/*
663 * Exit with error if file system is mounted.
664 */
665static void
666check_mounted(const char *fname, mode_t mode)
667{
668    struct statfs *mp;
669    const char *s1, *s2;
670    size_t len;
671    int n, r;
672
673    if (!(n = getmntinfo(&mp, MNT_NOWAIT)))
674	err(1, "getmntinfo");
675    len = strlen(_PATH_DEV);
676    s1 = fname;
677    if (!strncmp(s1, _PATH_DEV, len))
678	s1 += len;
679    r = S_ISCHR(mode) && s1 != fname && *s1 == 'r';
680    for (; n--; mp++) {
681	s2 = mp->f_mntfromname;
682	if (!strncmp(s2, _PATH_DEV, len))
683	    s2 += len;
684	if ((r && s2 != mp->f_mntfromname && !strcmp(s1 + 1, s2)) ||
685	    !strcmp(s1, s2))
686	    errx(1, "%s is mounted on %s", fname, mp->f_mntonname);
687    }
688}
689
690/*
691 * Get a standard format.
692 */
693static void
694getstdfmt(const char *fmt, struct bpb *bpb)
695{
696    u_int x, i;
697
698    x = sizeof(stdfmt) / sizeof(stdfmt[0]);
699    for (i = 0; i < x && strcmp(fmt, stdfmt[i].name); i++);
700    if (i == x)
701	errx(1, "%s: unknown standard format", fmt);
702    *bpb = stdfmt[i].bpb;
703}
704
705/*
706 * Get disk slice, partition, and geometry information.
707 */
708static void
709getdiskinfo(int fd, const char *fname, const char *dtype, int oflag,
710	    struct bpb *bpb)
711{
712    struct diskslices ds;
713    struct disklabel dl, *lp;
714    const char *s1, *s2;
715    char *s;
716    int slice, part, fd1, i, e;
717
718    slice = part = -1;
719    s1 = fname;
720    if ((s2 = strrchr(s1, '/')))
721	s1 = s2 + 1;
722    for (s2 = s1; *s2 && !isdigit(*s2); s2++);
723    if (!*s2 || s2 == s1)
724	s2 = NULL;
725    else
726	while (isdigit(*++s2));
727    s1 = s2;
728    if (s2 && *s2 == 's') {
729	slice = strtol(s2 + 1, &s, 10);
730	if (slice < 1 || slice > MAX_SLICES - BASE_SLICE)
731	    s2 = NULL;
732	else {
733	    slice = BASE_SLICE + slice - 1;
734	    s2 = s;
735	}
736    }
737    if (s2 && *s2 >= 'a' && *s2 <= 'a' + MAXPARTITIONS - 1) {
738	if (slice == -1)
739	    slice = COMPATIBILITY_SLICE;
740	part = *s2++ - 'a';
741    }
742    if (!s2 || (*s2 && *s2 != '.'))
743	errx(1, "%s: can't figure out partition info", fname);
744    if (slice != -1 && (!oflag || (!bpb->bsec && part == -1))) {
745	if (ioctl(fd, DIOCGSLICEINFO, &ds) == -1) {
746	    warn("ioctl (GSLICEINFO)");
747	    errx(1, "%s: can't get slice info", fname);
748	}
749	if (slice >= ds.dss_nslices || !ds.dss_slices[slice].ds_size)
750	    errx(1, "%s: slice is unavailable", fname);
751	if (!oflag)
752	    bpb->hid = ds.dss_slices[slice].ds_offset;
753	if (!bpb->bsec && part == -1)
754	    bpb->bsec = ds.dss_slices[slice].ds_size;
755    }
756    if (((slice == -1 || part != -1) &&
757	 ((!oflag && part != -1) || !bpb->bsec)) ||
758	!bpb->bps || !bpb->spt || !bpb->hds) {
759	lp = &dl;
760	i = ioctl(fd, DIOCGDINFO, lp);
761	if (i == -1 && slice != -1 && part == -1) {
762	    e = errno;
763	    if (!(s = strdup(fname)))
764		err(1, NULL);
765	    s[s1 - fname] = 0;
766	    if ((fd1 = open(s, O_RDONLY)) != -1) {
767		i = ioctl(fd1, DIOCGDINFO, lp);
768		close(fd1);
769	    }
770	    free(s);
771	    errno = e;
772	}
773	if (i == -1) {
774	    if (!dtype) {
775		warn("ioctl (GDINFO)");
776		errx(1, "%s: can't read disk label; "
777		     "disk type must be specified", fname);
778	    } else if (!(lp = getdiskbyname(dtype)))
779		errx(1, "%s: unknown disk type", dtype);
780	}
781	if (slice == -1 || part != -1) {
782	    if (part == -1)
783		part = RAW_PART;
784	    if (part >= lp->d_npartitions ||
785		!lp->d_partitions[part].p_size)
786		errx(1, "%s: partition is unavailable", fname);
787	    if (!oflag && part != -1)
788		bpb->hid += lp->d_partitions[part].p_offset;
789	    if (!bpb->bsec)
790		bpb->bsec = lp->d_partitions[part].p_size;
791	}
792	if (!bpb->bps)
793	    bpb->bps = ckgeom(fname, lp->d_secsize, "bytes/sector");
794	if (!bpb->spt)
795	    bpb->spt = ckgeom(fname, lp->d_nsectors, "sectors/track");
796	if (!bpb->hds)
797	    bpb->hds = ckgeom(fname, lp->d_ntracks, "drive heads");
798    }
799}
800
801/*
802 * Print out BPB values.
803 */
804static void
805print_bpb(struct bpb *bpb)
806{
807    printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
808	   bpb->nft);
809    if (bpb->rde)
810	printf(" rde=%u", bpb->rde);
811    if (bpb->sec)
812	printf(" sec=%u", bpb->sec);
813    printf(" mid=%#x", bpb->mid);
814    if (bpb->spf)
815	printf(" spf=%u", bpb->spf);
816    printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
817    if (bpb->bsec)
818	printf(" bsec=%u", bpb->bsec);
819    if (!bpb->spf) {
820	printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
821	printf(" infs=");
822	printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
823	printf(" bkbs=");
824	printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
825    }
826    printf("\n");
827}
828
829/*
830 * Check a disk geometry value.
831 */
832static u_int
833ckgeom(const char *fname, u_int val, const char *msg)
834{
835    if (!val)
836	errx(1, "%s: no default %s", fname, msg);
837    if (val > MAXU16)
838	errx(1, "%s: illegal %s", fname, msg);
839    return val;
840}
841
842/*
843 * Convert and check a numeric option argument.
844 */
845static u_int
846argtou(const char *arg, u_int lo, u_int hi, const char *msg)
847{
848    char *s;
849    u_long x;
850
851    errno = 0;
852    x = strtoul(arg, &s, 0);
853    if (errno || !*arg || *s || x < lo || x > hi)
854	errx(1, "%s: bad %s", arg, msg);
855    return x;
856}
857
858/*
859 * Check a volume label.
860 */
861static int
862oklabel(const char *src)
863{
864    int c, i;
865
866    for (i = 0; i <= 11; i++) {
867	c = (u_char)*src++;
868	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
869	    break;
870    }
871    return i && !c;
872}
873
874/*
875 * Make a volume label.
876 */
877static void
878mklabel(u_int8_t *dest, const char *src)
879{
880    int c, i;
881
882    for (i = 0; i < 11; i++) {
883	c = *src ? toupper(*src++) : ' ';
884	*dest++ = !i && c == '\xe5' ? 5 : c;
885    }
886}
887
888/*
889 * Copy string, padding with spaces.
890 */
891static void
892setstr(u_int8_t *dest, const char *src, size_t len)
893{
894    while (len--)
895	*dest++ = *src ? *src++ : ' ';
896}
897
898/*
899 * Print usage message.
900 */
901static void
902usage(void)
903{
904    fprintf(stderr,
905	    "usage: newfs_msdos [ -options ] special [disktype]\n");
906    fprintf(stderr, "where the options are:\n");
907    fprintf(stderr, "\t-N don't create file system: "
908	    "just print out parameters\n");
909    fprintf(stderr, "\t-B get bootstrap from file\n");
910    fprintf(stderr, "\t-F FAT type (12, 16, or 32)\n");
911    fprintf(stderr, "\t-I volume ID\n");
912    fprintf(stderr, "\t-L volume label\n");
913    fprintf(stderr, "\t-O OEM string\n");
914    fprintf(stderr, "\t-S bytes/sector\n");
915    fprintf(stderr, "\t-a sectors/FAT\n");
916    fprintf(stderr, "\t-b block size\n");
917    fprintf(stderr, "\t-c sectors/cluster\n");
918    fprintf(stderr, "\t-e root directory entries\n");
919    fprintf(stderr, "\t-f standard format\n");
920    fprintf(stderr, "\t-h drive heads\n");
921    fprintf(stderr, "\t-i file system info sector\n");
922    fprintf(stderr, "\t-k backup boot sector\n");
923    fprintf(stderr, "\t-m media descriptor\n");
924    fprintf(stderr, "\t-n number of FATs\n");
925    fprintf(stderr, "\t-o hidden sectors\n");
926    fprintf(stderr, "\t-r reserved sectors\n");
927    fprintf(stderr, "\t-s file system size (sectors)\n");
928    fprintf(stderr, "\t-u sectors/track\n");
929    exit(1);
930}
931