xref: /freebsd/sbin/newfs_msdos/newfs_msdos.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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
29 static const char rcsid[] =
30   "$FreeBSD$";
31 #endif /* not lint */
32 
33 #include <sys/param.h>
34 #include <sys/fdcio.h>
35 #include <sys/disk.h>
36 #include <sys/disklabel.h>
37 #include <sys/mount.h>
38 #include <sys/stat.h>
39 #include <sys/time.h>
40 
41 #include <ctype.h>
42 #include <err.h>
43 #include <errno.h>
44 #include <fcntl.h>
45 #include <paths.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <time.h>
50 #include <unistd.h>
51 
52 #define MAXU16	  0xffff	/* maximum unsigned 16-bit quantity */
53 #define BPN	  4		/* bits per nibble */
54 #define NPB	  2		/* nibbles per byte */
55 
56 #define DOSMAGIC  0xaa55	/* DOS magic number */
57 #define MINBPS	  512		/* minimum bytes per sector */
58 #define MAXSPC	  128		/* maximum sectors per cluster */
59 #define MAXNFT	  16		/* maximum number of FATs */
60 #define DEFBLK	  4096		/* default block size */
61 #define DEFBLK16  2048		/* default block size FAT16 */
62 #define DEFRDE	  512		/* default root directory entries */
63 #define RESFTE	  2		/* reserved FAT entries */
64 #define MINCLS12  1		/* minimum FAT12 clusters */
65 #define MINCLS16  0x1000	/* minimum FAT16 clusters */
66 #define MINCLS32  2		/* minimum FAT32 clusters */
67 #define MAXCLS12  0xfed 	/* maximum FAT12 clusters */
68 #define MAXCLS16  0xfff5	/* maximum FAT16 clusters */
69 #define MAXCLS32  0xffffff5	/* maximum FAT32 clusters */
70 
71 #define mincls(fat)  ((fat) == 12 ? MINCLS12 :	\
72 		      (fat) == 16 ? MINCLS16 :	\
73 				    MINCLS32)
74 
75 #define maxcls(fat)  ((fat) == 12 ? MAXCLS12 :	\
76 		      (fat) == 16 ? MAXCLS16 :	\
77 				    MAXCLS32)
78 
79 #define mk1(p, x)				\
80     (p) = (u_int8_t)(x)
81 
82 #define mk2(p, x)				\
83     (p)[0] = (u_int8_t)(x),			\
84     (p)[1] = (u_int8_t)((x) >> 010)
85 
86 #define mk4(p, x)				\
87     (p)[0] = (u_int8_t)(x),			\
88     (p)[1] = (u_int8_t)((x) >> 010),		\
89     (p)[2] = (u_int8_t)((x) >> 020),		\
90     (p)[3] = (u_int8_t)((x) >> 030)
91 
92 #define argto1(arg, lo, msg)  argtou(arg, lo, 0xff, msg)
93 #define argto2(arg, lo, msg)  argtou(arg, lo, 0xffff, msg)
94 #define argto4(arg, lo, msg)  argtou(arg, lo, 0xffffffff, msg)
95 #define argtox(arg, lo, msg)  argtou(arg, lo, UINT_MAX, msg)
96 
97 struct bs {
98     u_int8_t jmp[3];		/* bootstrap entry point */
99     u_int8_t oem[8];		/* OEM name and version */
100 };
101 
102 struct bsbpb {
103     u_int8_t bps[2];		/* bytes per sector */
104     u_int8_t spc;		/* sectors per cluster */
105     u_int8_t res[2];		/* reserved sectors */
106     u_int8_t nft;		/* number of FATs */
107     u_int8_t rde[2];		/* root directory entries */
108     u_int8_t sec[2];		/* total sectors */
109     u_int8_t mid;		/* media descriptor */
110     u_int8_t spf[2];		/* sectors per FAT */
111     u_int8_t spt[2];		/* sectors per track */
112     u_int8_t hds[2];		/* drive heads */
113     u_int8_t hid[4];		/* hidden sectors */
114     u_int8_t bsec[4];		/* big total sectors */
115 };
116 
117 struct bsxbpb {
118     u_int8_t bspf[4];		/* big sectors per FAT */
119     u_int8_t xflg[2];		/* FAT control flags */
120     u_int8_t vers[2];		/* file system version */
121     u_int8_t rdcl[4];		/* root directory start cluster */
122     u_int8_t infs[2];		/* file system info sector */
123     u_int8_t bkbs[2];		/* backup boot sector */
124     u_int8_t rsvd[12];		/* reserved */
125 };
126 
127 struct bsx {
128     u_int8_t drv;		/* drive number */
129     u_int8_t rsvd;		/* reserved */
130     u_int8_t sig;		/* extended boot signature */
131     u_int8_t volid[4];		/* volume ID number */
132     u_int8_t label[11]; 	/* volume label */
133     u_int8_t type[8];		/* file system type */
134 };
135 
136 struct de {
137     u_int8_t namext[11];	/* name and extension */
138     u_int8_t attr;		/* attributes */
139     u_int8_t rsvd[10];		/* reserved */
140     u_int8_t time[2];		/* creation time */
141     u_int8_t date[2];		/* creation date */
142     u_int8_t clus[2];		/* starting cluster */
143     u_int8_t size[4];		/* size */
144 };
145 
146 struct bpb {
147     u_int bps;			/* bytes per sector */
148     u_int spc;			/* sectors per cluster */
149     u_int res;			/* reserved sectors */
150     u_int nft;			/* number of FATs */
151     u_int rde;			/* root directory entries */
152     u_int sec;			/* total sectors */
153     u_int mid;			/* media descriptor */
154     u_int spf;			/* sectors per FAT */
155     u_int spt;			/* sectors per track */
156     u_int hds;			/* drive heads */
157     u_int hid;			/* hidden sectors */
158     u_int bsec; 		/* big total sectors */
159     u_int bspf; 		/* big sectors per FAT */
160     u_int rdcl; 		/* root directory start cluster */
161     u_int infs; 		/* file system info sector */
162     u_int bkbs; 		/* backup boot sector */
163 };
164 
165 #define BPBGAP 0, 0, 0, 0, 0, 0
166 
167 static struct {
168     const char *name;
169     struct bpb bpb;
170 } stdfmt[] = {
171     {"160",  {512, 1, 1, 2,  64,  320, 0xfe, 1,  8, 1, BPBGAP}},
172     {"180",  {512, 1, 1, 2,  64,  360, 0xfc, 2,  9, 1, BPBGAP}},
173     {"320",  {512, 2, 1, 2, 112,  640, 0xff, 1,  8, 2, BPBGAP}},
174     {"360",  {512, 2, 1, 2, 112,  720, 0xfd, 2,  9, 2, BPBGAP}},
175     {"640",  {512, 2, 1, 2, 112, 1280, 0xfb, 2,  8, 2, BPBGAP}},
176     {"720",  {512, 2, 1, 2, 112, 1440, 0xf9, 3,  9, 2, BPBGAP}},
177     {"1200", {512, 1, 1, 2, 224, 2400, 0xf9, 7, 15, 2, BPBGAP}},
178     {"1232", {1024,1, 1, 2, 192, 1232, 0xfe, 2,  8, 2, BPBGAP}},
179     {"1440", {512, 1, 1, 2, 224, 2880, 0xf0, 9, 18, 2, BPBGAP}},
180     {"2880", {512, 2, 1, 2, 240, 5760, 0xf0, 9, 36, 2, BPBGAP}}
181 };
182 
183 static u_int8_t bootcode[] = {
184     0xfa,			/* cli		    */
185     0x31, 0xc0, 		/* xor	   ax,ax    */
186     0x8e, 0xd0, 		/* mov	   ss,ax    */
187     0xbc, 0x00, 0x7c,		/* mov	   sp,7c00h */
188     0xfb,			/* sti		    */
189     0x8e, 0xd8, 		/* mov	   ds,ax    */
190     0xe8, 0x00, 0x00,		/* call    $ + 3    */
191     0x5e,			/* pop	   si	    */
192     0x83, 0xc6, 0x19,		/* add	   si,+19h  */
193     0xbb, 0x07, 0x00,		/* mov	   bx,0007h */
194     0xfc,			/* cld		    */
195     0xac,			/* lodsb	    */
196     0x84, 0xc0, 		/* test    al,al    */
197     0x74, 0x06, 		/* jz	   $ + 8    */
198     0xb4, 0x0e, 		/* mov	   ah,0eh   */
199     0xcd, 0x10, 		/* int	   10h	    */
200     0xeb, 0xf5, 		/* jmp	   $ - 9    */
201     0x30, 0xe4, 		/* xor	   ah,ah    */
202     0xcd, 0x16, 		/* int	   16h	    */
203     0xcd, 0x19, 		/* int	   19h	    */
204     0x0d, 0x0a,
205     'N', 'o', 'n', '-', 's', 'y', 's', 't',
206     'e', 'm', ' ', 'd', 'i', 's', 'k',
207     0x0d, 0x0a,
208     'P', 'r', 'e', 's', 's', ' ', 'a', 'n',
209     'y', ' ', 'k', 'e', 'y', ' ', 't', 'o',
210     ' ', 'r', 'e', 'b', 'o', 'o', 't',
211     0x0d, 0x0a,
212     0
213 };
214 
215 static void check_mounted(const char *, mode_t);
216 static void getstdfmt(const char *, struct bpb *);
217 static void getdiskinfo(int, const char *, const char *, int,
218 			struct bpb *);
219 static void print_bpb(struct bpb *);
220 static u_int ckgeom(const char *, u_int, const char *);
221 static u_int argtou(const char *, u_int, u_int, const char *);
222 static int oklabel(const char *);
223 static void mklabel(u_int8_t *, const char *);
224 static void setstr(u_int8_t *, const char *, size_t);
225 static void usage(void);
226 
227 /*
228  * Construct a FAT12, FAT16, or FAT32 file system.
229  */
230 int
231 main(int argc, char *argv[])
232 {
233     static char opts[] = "NB:F:I:L:O:S:a:b:c:e:f:h:i:k:m:n:o:r:s:u:";
234     static const char *opt_B, *opt_L, *opt_O, *opt_f;
235     static u_int opt_F, opt_I, opt_S, opt_a, opt_b, opt_c, opt_e;
236     static u_int opt_h, opt_i, opt_k, opt_m, opt_n, opt_o, opt_r;
237     static u_int opt_s, opt_u;
238     static int opt_N;
239     static int Iflag, mflag, oflag;
240     char buf[MAXPATHLEN];
241     struct stat sb;
242     struct timeval tv;
243     struct bpb bpb;
244     struct tm *tm;
245     struct bs *bs;
246     struct bsbpb *bsbpb;
247     struct bsxbpb *bsxbpb;
248     struct bsx *bsx;
249     struct de *de;
250     u_int8_t *img;
251     const char *fname, *dtype, *bname;
252     ssize_t n;
253     time_t now;
254     u_int fat, bss, rds, cls, dir, lsn, x, x1, x2;
255     int ch, fd, fd1;
256 
257     while ((ch = getopt(argc, argv, opts)) != -1)
258 	switch (ch) {
259 	case 'N':
260 	    opt_N = 1;
261 	    break;
262 	case 'B':
263 	    opt_B = optarg;
264 	    break;
265 	case 'F':
266 	    if (strcmp(optarg, "12") &&
267 		strcmp(optarg, "16") &&
268 		strcmp(optarg, "32"))
269 		errx(1, "%s: bad FAT type", optarg);
270 	    opt_F = atoi(optarg);
271 	    break;
272 	case 'I':
273 	    opt_I = argto4(optarg, 0, "volume ID");
274 	    Iflag = 1;
275 	    break;
276 	case 'L':
277 	    if (!oklabel(optarg))
278 		errx(1, "%s: bad volume label", optarg);
279 	    opt_L = optarg;
280 	    break;
281 	case 'O':
282 	    if (strlen(optarg) > 8)
283 		errx(1, "%s: bad OEM string", optarg);
284 	    opt_O = optarg;
285 	    break;
286 	case 'S':
287 	    opt_S = argto2(optarg, 1, "bytes/sector");
288 	    break;
289 	case 'a':
290 	    opt_a = argto4(optarg, 1, "sectors/FAT");
291 	    break;
292 	case 'b':
293 	    opt_b = argtox(optarg, 1, "block size");
294 	    opt_c = 0;
295 	    break;
296 	case 'c':
297 	    opt_c = argto1(optarg, 1, "sectors/cluster");
298 	    opt_b = 0;
299 	    break;
300 	case 'e':
301 	    opt_e = argto2(optarg, 1, "directory entries");
302 	    break;
303 	case 'f':
304 	    opt_f = optarg;
305 	    break;
306 	case 'h':
307 	    opt_h = argto2(optarg, 1, "drive heads");
308 	    break;
309 	case 'i':
310 	    opt_i = argto2(optarg, 1, "info sector");
311 	    break;
312 	case 'k':
313 	    opt_k = argto2(optarg, 1, "backup sector");
314 	    break;
315 	case 'm':
316 	    opt_m = argto1(optarg, 0, "media descriptor");
317 	    mflag = 1;
318 	    break;
319 	case 'n':
320 	    opt_n = argto1(optarg, 1, "number of FATs");
321 	    break;
322 	case 'o':
323 	    opt_o = argto4(optarg, 0, "hidden sectors");
324 	    oflag = 1;
325 	    break;
326 	case 'r':
327 	    opt_r = argto2(optarg, 1, "reserved sectors");
328 	    break;
329 	case 's':
330 	    opt_s = argto4(optarg, 1, "file system size");
331 	    break;
332 	case 'u':
333 	    opt_u = argto2(optarg, 1, "sectors/track");
334 	    break;
335 	default:
336 	    usage();
337 	}
338     argc -= optind;
339     argv += optind;
340     if (argc < 1 || argc > 2)
341 	usage();
342     fname = *argv++;
343     if (!strchr(fname, '/')) {
344 	snprintf(buf, sizeof(buf), "%s%s", _PATH_DEV, fname);
345 	if (!(fname = strdup(buf)))
346 	    err(1, NULL);
347     }
348     dtype = *argv;
349     if ((fd = open(fname, opt_N ? O_RDONLY : O_RDWR)) == -1 ||
350 	fstat(fd, &sb))
351 	err(1, "%s", fname);
352     if (!opt_N)
353 	check_mounted(fname, sb.st_mode);
354     if (!S_ISCHR(sb.st_mode))
355 	warnx("warning: %s is not a character device", fname);
356     memset(&bpb, 0, sizeof(bpb));
357     if (opt_f) {
358 	getstdfmt(opt_f, &bpb);
359 	bpb.bsec = bpb.sec;
360 	bpb.sec = 0;
361 	bpb.bspf = bpb.spf;
362 	bpb.spf = 0;
363     }
364     if (opt_h)
365 	bpb.hds = opt_h;
366     if (opt_u)
367 	bpb.spt = opt_u;
368     if (opt_S)
369 	bpb.bps = opt_S;
370     if (opt_s)
371 	bpb.bsec = opt_s;
372     if (oflag)
373 	bpb.hid = opt_o;
374     if (!(opt_f || (opt_h && opt_u && opt_S && opt_s && oflag)))
375 	getdiskinfo(fd, fname, dtype, oflag, &bpb);
376     if (!powerof2(bpb.bps))
377 	errx(1, "bytes/sector (%u) is not a power of 2", bpb.bps);
378     if (bpb.bps < MINBPS)
379 	errx(1, "bytes/sector (%u) is too small; minimum is %u",
380 	     bpb.bps, MINBPS);
381     if (!(fat = opt_F)) {
382 	if (opt_f)
383 	    fat = 12;
384 	else if (!opt_e && (opt_i || opt_k))
385 	    fat = 32;
386     }
387     if ((fat == 32 && opt_e) || (fat != 32 && (opt_i || opt_k)))
388 	errx(1, "-%c is not a legal FAT%s option",
389 	     fat == 32 ? 'e' : opt_i ? 'i' : 'k',
390 	     fat == 32 ? "32" : "12/16");
391     if (opt_f && fat == 32)
392 	bpb.rde = 0;
393     if (opt_b) {
394 	if (!powerof2(opt_b))
395 	    errx(1, "block size (%u) is not a power of 2", opt_b);
396 	if (opt_b < bpb.bps)
397 	    errx(1, "block size (%u) is too small; minimum is %u",
398 		 opt_b, bpb.bps);
399 	if (opt_b > bpb.bps * MAXSPC)
400 	    errx(1, "block size (%u) is too large; maximum is %u",
401 		 opt_b, bpb.bps * MAXSPC);
402 	bpb.spc = opt_b / bpb.bps;
403     }
404     if (opt_c) {
405 	if (!powerof2(opt_c))
406 	    errx(1, "sectors/cluster (%u) is not a power of 2", opt_c);
407 	bpb.spc = opt_c;
408     }
409     if (opt_r)
410 	bpb.res = opt_r;
411     if (opt_n) {
412 	if (opt_n > MAXNFT)
413 	    errx(1, "number of FATs (%u) is too large; maximum is %u",
414 		 opt_n, MAXNFT);
415 	bpb.nft = opt_n;
416     }
417     if (opt_e)
418 	bpb.rde = opt_e;
419     if (mflag) {
420 	if (opt_m < 0xf0)
421 	    errx(1, "illegal media descriptor (%#x)", opt_m);
422 	bpb.mid = opt_m;
423     }
424     if (opt_a)
425 	bpb.bspf = opt_a;
426     if (opt_i)
427 	bpb.infs = opt_i;
428     if (opt_k)
429 	bpb.bkbs = opt_k;
430     bss = 1;
431     bname = NULL;
432     fd1 = -1;
433     if (opt_B) {
434 	bname = opt_B;
435 	if (!strchr(bname, '/')) {
436 	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
437 	    if (!(bname = strdup(buf)))
438 		err(1, NULL);
439 	}
440 	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb))
441 	    err(1, "%s", bname);
442 	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bps ||
443 	    sb.st_size < bpb.bps || sb.st_size > bpb.bps * MAXU16)
444 	    errx(1, "%s: inappropriate file type or format", bname);
445 	bss = sb.st_size / bpb.bps;
446     }
447     if (!bpb.nft)
448 	bpb.nft = 2;
449     if (!fat) {
450 	if (bpb.bsec < (bpb.res ? bpb.res : bss) +
451 	    howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
452 		    ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
453 	    bpb.nft +
454 	    howmany(bpb.rde ? bpb.rde : DEFRDE,
455 		    bpb.bps / sizeof(struct de)) +
456 	    (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
457 	    (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
458 	    fat = 12;
459 	else if (bpb.rde || bpb.bsec <
460 		 (bpb.res ? bpb.res : bss) +
461 		 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
462 		 howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
463 		 (MAXCLS16 + 1) *
464 		 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
465 	    fat = 16;
466 	else
467 	    fat = 32;
468     }
469     x = bss;
470     if (fat == 32) {
471 	if (!bpb.infs) {
472 	    if (x == MAXU16 || x == bpb.bkbs)
473 		errx(1, "no room for info sector");
474 	    bpb.infs = x;
475 	}
476 	if (bpb.infs != MAXU16 && x <= bpb.infs)
477 	    x = bpb.infs + 1;
478 	if (!bpb.bkbs) {
479 	    if (x == MAXU16)
480 		errx(1, "no room for backup sector");
481 	    bpb.bkbs = x;
482 	} else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs)
483 	    errx(1, "backup sector would overwrite info sector");
484 	if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
485 	    x = bpb.bkbs + 1;
486     }
487     if (!bpb.res)
488 	bpb.res = fat == 32 ? MAX(x, MAX(16384 / bpb.bps, 4)) : x;
489     else if (bpb.res < x)
490 	errx(1, "too few reserved sectors");
491     if (fat != 32 && !bpb.rde)
492 	bpb.rde = DEFRDE;
493     rds = howmany(bpb.rde, bpb.bps / sizeof(struct de));
494     if (!bpb.spc)
495 	for (bpb.spc = howmany(fat == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
496 	     bpb.spc < MAXSPC &&
497 	     bpb.res +
498 	     howmany((RESFTE + maxcls(fat)) * (fat / BPN),
499 		     bpb.bps * NPB) * bpb.nft +
500 	     rds +
501 	     (u_int64_t)(maxcls(fat) + 1) * bpb.spc <= bpb.bsec;
502 	     bpb.spc <<= 1);
503     if (fat != 32 && bpb.bspf > MAXU16)
504 	errx(1, "too many sectors/FAT for FAT12/16");
505     x1 = bpb.res + rds;
506     x = bpb.bspf ? bpb.bspf : 1;
507     if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec)
508 	errx(1, "meta data exceeds file system size");
509     x1 += x * bpb.nft;
510     x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
511 	(bpb.spc * bpb.bps * NPB + fat / BPN * bpb.nft);
512     x2 = howmany((RESFTE + MIN(x, maxcls(fat))) * (fat / BPN),
513 		 bpb.bps * NPB);
514     if (!bpb.bspf) {
515 	bpb.bspf = x2;
516 	x1 += (bpb.bspf - 1) * bpb.nft;
517     }
518     cls = (bpb.bsec - x1) / bpb.spc;
519     x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (fat / BPN) - RESFTE;
520     if (cls > x)
521 	cls = x;
522     if (bpb.bspf < x2)
523 	warnx("warning: sectors/FAT limits file system to %u clusters",
524 	      cls);
525     if (cls < mincls(fat))
526 	errx(1, "%u clusters too few clusters for FAT%u, need %u", cls, fat,
527 	    mincls(fat));
528     if (cls > maxcls(fat)) {
529 	cls = maxcls(fat);
530 	bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
531 	warnx("warning: FAT type limits file system to %u sectors",
532 	      bpb.bsec);
533     }
534     printf("%s: %u sector%s in %u FAT%u cluster%s "
535 	   "(%u bytes/cluster)\n", fname, cls * bpb.spc,
536 	   cls * bpb.spc == 1 ? "" : "s", cls, fat,
537 	   cls == 1 ? "" : "s", bpb.bps * bpb.spc);
538     if (!bpb.mid)
539 	bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
540     if (fat == 32)
541 	bpb.rdcl = RESFTE;
542     if (bpb.hid + bpb.bsec <= MAXU16) {
543 	bpb.sec = bpb.bsec;
544 	bpb.bsec = 0;
545     }
546     if (fat != 32) {
547 	bpb.spf = bpb.bspf;
548 	bpb.bspf = 0;
549     }
550     print_bpb(&bpb);
551     if (!opt_N) {
552 	gettimeofday(&tv, NULL);
553 	now = tv.tv_sec;
554 	tm = localtime(&now);
555 	if (!(img = malloc(bpb.bps)))
556 	    err(1, NULL);
557 	dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;
558 	for (lsn = 0; lsn < dir + (fat == 32 ? bpb.spc : rds); lsn++) {
559 	    x = lsn;
560 	    if (opt_B &&
561 		fat == 32 && bpb.bkbs != MAXU16 &&
562 		bss <= bpb.bkbs && x >= bpb.bkbs) {
563 		x -= bpb.bkbs;
564 		if (!x && lseek(fd1, 0, SEEK_SET))
565 		    err(1, "%s", bname);
566 	    }
567 	    if (opt_B && x < bss) {
568 		if ((n = read(fd1, img, bpb.bps)) == -1)
569 		    err(1, "%s", bname);
570 		if ((unsigned)n != bpb.bps)
571 		    errx(1, "%s: can't read sector %u", bname, x);
572 	    } else
573 		memset(img, 0, bpb.bps);
574 	    if (!lsn ||
575 	      (fat == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
576 		x1 = sizeof(struct bs);
577 		bsbpb = (struct bsbpb *)(img + x1);
578 		mk2(bsbpb->bps, bpb.bps);
579 		mk1(bsbpb->spc, bpb.spc);
580 		mk2(bsbpb->res, bpb.res);
581 		mk1(bsbpb->nft, bpb.nft);
582 		mk2(bsbpb->rde, bpb.rde);
583 		mk2(bsbpb->sec, bpb.sec);
584 		mk1(bsbpb->mid, bpb.mid);
585 		mk2(bsbpb->spf, bpb.spf);
586 		mk2(bsbpb->spt, bpb.spt);
587 		mk2(bsbpb->hds, bpb.hds);
588 		mk4(bsbpb->hid, bpb.hid);
589 		mk4(bsbpb->bsec, bpb.bsec);
590 		x1 += sizeof(struct bsbpb);
591 		if (fat == 32) {
592 		    bsxbpb = (struct bsxbpb *)(img + x1);
593 		    mk4(bsxbpb->bspf, bpb.bspf);
594 		    mk2(bsxbpb->xflg, 0);
595 		    mk2(bsxbpb->vers, 0);
596 		    mk4(bsxbpb->rdcl, bpb.rdcl);
597 		    mk2(bsxbpb->infs, bpb.infs);
598 		    mk2(bsxbpb->bkbs, bpb.bkbs);
599 		    x1 += sizeof(struct bsxbpb);
600 		}
601 		bsx = (struct bsx *)(img + x1);
602 		mk1(bsx->sig, 0x29);
603 		if (Iflag)
604 		    x = opt_I;
605 		else
606 		    x = (((u_int)(1 + tm->tm_mon) << 8 |
607 			  (u_int)tm->tm_mday) +
608 			 ((u_int)tm->tm_sec << 8 |
609 			  (u_int)(tv.tv_usec / 10))) << 16 |
610 			((u_int)(1900 + tm->tm_year) +
611 			 ((u_int)tm->tm_hour << 8 |
612 			  (u_int)tm->tm_min));
613 		mk4(bsx->volid, x);
614 		mklabel(bsx->label, opt_L ? opt_L : "NO NAME");
615 		sprintf(buf, "FAT%u", fat);
616 		setstr(bsx->type, buf, sizeof(bsx->type));
617 		if (!opt_B) {
618 		    x1 += sizeof(struct bsx);
619 		    bs = (struct bs *)img;
620 		    mk1(bs->jmp[0], 0xeb);
621 		    mk1(bs->jmp[1], x1 - 2);
622 		    mk1(bs->jmp[2], 0x90);
623 		    setstr(bs->oem, opt_O ? opt_O : "BSD  4.4",
624 			   sizeof(bs->oem));
625 		    memcpy(img + x1, bootcode, sizeof(bootcode));
626 		    mk2(img + MINBPS - 2, DOSMAGIC);
627 		}
628 	    } else if (fat == 32 && bpb.infs != MAXU16 &&
629 		       (lsn == bpb.infs ||
630 			(bpb.bkbs != MAXU16 &&
631 			 lsn == bpb.bkbs + bpb.infs))) {
632 		mk4(img, 0x41615252);
633 		mk4(img + MINBPS - 28, 0x61417272);
634 		mk4(img + MINBPS - 24, 0xffffffff);
635 		mk4(img + MINBPS - 20, bpb.rdcl);
636 		mk2(img + MINBPS - 2, DOSMAGIC);
637 	    } else if (lsn >= bpb.res && lsn < dir &&
638 		       !((lsn - bpb.res) %
639 			 (bpb.spf ? bpb.spf : bpb.bspf))) {
640 		mk1(img[0], bpb.mid);
641 		for (x = 1; x < fat * (fat == 32 ? 3 : 2) / 8; x++)
642 		    mk1(img[x], fat == 32 && x % 4 == 3 ? 0x0f : 0xff);
643 	    } else if (lsn == dir && opt_L) {
644 		de = (struct de *)img;
645 		mklabel(de->namext, opt_L);
646 		mk1(de->attr, 050);
647 		x = (u_int)tm->tm_hour << 11 |
648 		    (u_int)tm->tm_min << 5 |
649 		    (u_int)tm->tm_sec >> 1;
650 		mk2(de->time, x);
651 		x = (u_int)(tm->tm_year - 80) << 9 |
652 		    (u_int)(tm->tm_mon + 1) << 5 |
653 		    (u_int)tm->tm_mday;
654 		mk2(de->date, x);
655 	    }
656 	    if ((n = write(fd, img, bpb.bps)) == -1)
657 		err(1, "%s", fname);
658 	    if ((unsigned)n != bpb.bps)
659 		errx(1, "%s: can't write sector %u", fname, lsn);
660 	}
661     }
662     return 0;
663 }
664 
665 /*
666  * Exit with error if file system is mounted.
667  */
668 static void
669 check_mounted(const char *fname, mode_t mode)
670 {
671     struct statfs *mp;
672     const char *s1, *s2;
673     size_t len;
674     int n, r;
675 
676     if (!(n = getmntinfo(&mp, MNT_NOWAIT)))
677 	err(1, "getmntinfo");
678     len = strlen(_PATH_DEV);
679     s1 = fname;
680     if (!strncmp(s1, _PATH_DEV, len))
681 	s1 += len;
682     r = S_ISCHR(mode) && s1 != fname && *s1 == 'r';
683     for (; n--; mp++) {
684 	s2 = mp->f_mntfromname;
685 	if (!strncmp(s2, _PATH_DEV, len))
686 	    s2 += len;
687 	if ((r && s2 != mp->f_mntfromname && !strcmp(s1 + 1, s2)) ||
688 	    !strcmp(s1, s2))
689 	    errx(1, "%s is mounted on %s", fname, mp->f_mntonname);
690     }
691 }
692 
693 /*
694  * Get a standard format.
695  */
696 static void
697 getstdfmt(const char *fmt, struct bpb *bpb)
698 {
699     u_int x, i;
700 
701     x = sizeof(stdfmt) / sizeof(stdfmt[0]);
702     for (i = 0; i < x && strcmp(fmt, stdfmt[i].name); i++);
703     if (i == x)
704 	errx(1, "%s: unknown standard format", fmt);
705     *bpb = stdfmt[i].bpb;
706 }
707 
708 /*
709  * Get disk slice, partition, and geometry information.
710  */
711 static void
712 getdiskinfo(int fd, const char *fname, const char *dtype, __unused int oflag,
713 	    struct bpb *bpb)
714 {
715     struct disklabel *lp, dlp;
716     struct fd_type type;
717     off_t ms, hs = 0;
718 
719     lp = NULL;
720 
721     /* If the user specified a disk type, try to use that */
722     if (dtype != NULL) {
723 	lp = getdiskbyname(dtype);
724     }
725 
726     /* Maybe it's a floppy drive */
727     if (lp == NULL) {
728 	if (ioctl(fd, DIOCGMEDIASIZE, &ms) == -1)
729 	    errx(1, "Cannot get disk size, %s", strerror(errno));
730 	if (ioctl(fd, FD_GTYPE, &type) != -1) {
731 	    dlp.d_secsize = 128 << type.secsize;
732 	    dlp.d_nsectors = type.sectrac;
733 	    dlp.d_ntracks = type.heads;
734 	    dlp.d_secperunit = ms / dlp.d_secsize;
735 	    lp = &dlp;
736 	}
737     }
738 
739     /* Maybe it's a fixed drive */
740     if (lp == NULL) {
741 	if (ioctl(fd, DIOCGDINFO, &dlp) == -1) {
742 	    if (ioctl(fd, DIOCGSECTORSIZE, &dlp.d_secsize) == -1)
743 		errx(1, "Cannot get sector size, %s", strerror(errno));
744 	    if (ioctl(fd, DIOCGFWSECTORS, &dlp.d_nsectors) == -1)
745 		errx(1, "Cannot get number of sectors, %s", strerror(errno));
746 	    if (ioctl(fd, DIOCGFWHEADS, &dlp.d_ntracks)== -1)
747 		errx(1, "Cannot get number of heads, %s", strerror(errno));
748 	    dlp.d_secperunit = ms / dlp.d_secsize;
749 	}
750 
751 	hs = (ms / dlp.d_secsize) - dlp.d_secperunit;
752 	lp = &dlp;
753     }
754 
755     if (bpb->bps == 0)
756 	bpb->bps = ckgeom(fname, lp->d_secsize, "bytes/sector");
757     if (bpb->spt == 0)
758 	bpb->spt = ckgeom(fname, lp->d_nsectors, "sectors/track");
759     if (bpb->hds == 0)
760 	bpb->hds = ckgeom(fname, lp->d_ntracks, "drive heads");
761     if (bpb->bsec == 0)
762 	bpb->bsec = lp->d_secperunit;
763     if (bpb->hid == 0)
764 	bpb->hid = hs;
765 }
766 
767 /*
768  * Print out BPB values.
769  */
770 static void
771 print_bpb(struct bpb *bpb)
772 {
773     printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
774 	   bpb->nft);
775     if (bpb->rde)
776 	printf(" rde=%u", bpb->rde);
777     if (bpb->sec)
778 	printf(" sec=%u", bpb->sec);
779     printf(" mid=%#x", bpb->mid);
780     if (bpb->spf)
781 	printf(" spf=%u", bpb->spf);
782     printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
783     if (bpb->bsec)
784 	printf(" bsec=%u", bpb->bsec);
785     if (!bpb->spf) {
786 	printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
787 	printf(" infs=");
788 	printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
789 	printf(" bkbs=");
790 	printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
791     }
792     printf("\n");
793 }
794 
795 /*
796  * Check a disk geometry value.
797  */
798 static u_int
799 ckgeom(const char *fname, u_int val, const char *msg)
800 {
801     if (!val)
802 	errx(1, "%s: no default %s", fname, msg);
803     if (val > MAXU16)
804 	errx(1, "%s: illegal %s %d", fname, msg, val);
805     return val;
806 }
807 
808 /*
809  * Convert and check a numeric option argument.
810  */
811 static u_int
812 argtou(const char *arg, u_int lo, u_int hi, const char *msg)
813 {
814     char *s;
815     u_long x;
816 
817     errno = 0;
818     x = strtoul(arg, &s, 0);
819     if (errno || !*arg || *s || x < lo || x > hi)
820 	errx(1, "%s: bad %s", arg, msg);
821     return x;
822 }
823 
824 /*
825  * Check a volume label.
826  */
827 static int
828 oklabel(const char *src)
829 {
830     int c, i;
831 
832     for (i = 0; i <= 11; i++) {
833 	c = (u_char)*src++;
834 	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
835 	    break;
836     }
837     return i && !c;
838 }
839 
840 /*
841  * Make a volume label.
842  */
843 static void
844 mklabel(u_int8_t *dest, const char *src)
845 {
846     int c, i;
847 
848     for (i = 0; i < 11; i++) {
849 	c = *src ? toupper(*src++) : ' ';
850 	*dest++ = !i && c == '\xe5' ? 5 : c;
851     }
852 }
853 
854 /*
855  * Copy string, padding with spaces.
856  */
857 static void
858 setstr(u_int8_t *dest, const char *src, size_t len)
859 {
860     while (len--)
861 	*dest++ = *src ? *src++ : ' ';
862 }
863 
864 /*
865  * Print usage message.
866  */
867 static void
868 usage(void)
869 {
870     fprintf(stderr,
871 	    "usage: newfs_msdos [ -options ] special [disktype]\n");
872     fprintf(stderr, "where the options are:\n");
873     fprintf(stderr, "\t-N don't create file system: "
874 	    "just print out parameters\n");
875     fprintf(stderr, "\t-B get bootstrap from file\n");
876     fprintf(stderr, "\t-F FAT type (12, 16, or 32)\n");
877     fprintf(stderr, "\t-I volume ID\n");
878     fprintf(stderr, "\t-L volume label\n");
879     fprintf(stderr, "\t-O OEM string\n");
880     fprintf(stderr, "\t-S bytes/sector\n");
881     fprintf(stderr, "\t-a sectors/FAT\n");
882     fprintf(stderr, "\t-b block size\n");
883     fprintf(stderr, "\t-c sectors/cluster\n");
884     fprintf(stderr, "\t-e root directory entries\n");
885     fprintf(stderr, "\t-f standard format\n");
886     fprintf(stderr, "\t-h drive heads\n");
887     fprintf(stderr, "\t-i file system info sector\n");
888     fprintf(stderr, "\t-k backup boot sector\n");
889     fprintf(stderr, "\t-m media descriptor\n");
890     fprintf(stderr, "\t-n number of FATs\n");
891     fprintf(stderr, "\t-o hidden sectors\n");
892     fprintf(stderr, "\t-r reserved sectors\n");
893     fprintf(stderr, "\t-s file system size (sectors)\n");
894     fprintf(stderr, "\t-u sectors/track\n");
895     exit(1);
896 }
897