xref: /openbsd/sbin/newfs_msdos/newfs_msdos.c (revision b205d946)
1 /*	$OpenBSD: newfs_msdos.c,v 1.29 2024/04/28 16:43:42 florian 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 #include <sys/param.h>	/* powerof2 */
31 #include <sys/stat.h>
32 #include <sys/disklabel.h>
33 #include <sys/ioctl.h>
34 #include <sys/dkio.h>
35 #include <sys/mount.h>
36 
37 #include <ctype.h>
38 #include <err.h>
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <paths.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46 #include <limits.h>
47 #include <util.h>
48 
49 #define MINIMUM(a, b)	(((a) < (b)) ? (a) : (b))
50 #define MAXIMUM(a, b)	(((a) > (b)) ? (a) : (b))
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  0xff5		/* minimum FAT16 clusters */
66 #define MINCLS32  0xfff5	/* minimum FAT32 clusters */
67 #define MAXCLS12  0xff4		/* maximum FAT12 clusters */
68 #define MAXCLS16  0xfff4	/* maximum FAT16 clusters */
69 #define MAXCLS32  0xffffff4	/* 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 static struct {
166     const char *name;
167     struct bpb bpb;
168 } stdfmt[] = {
169     {"160",  {512, 1, 1, 2,  64,  320, 0xfe, 1,  8, 1}},
170     {"180",  {512, 1, 1, 2,  64,  360, 0xfc, 2,  9, 1}},
171     {"320",  {512, 2, 1, 2, 112,  640, 0xff, 1,  8, 2}},
172     {"360",  {512, 2, 1, 2, 112,  720, 0xfd, 2,  9, 2}},
173     {"720",  {512, 2, 1, 2, 112, 1440, 0xf9, 3,  9, 2}},
174     {"1200", {512, 1, 1, 2, 224, 2400, 0xf9, 7, 15, 2}},
175     {"1440", {512, 1, 1, 2, 224, 2880, 0xf0, 9, 18, 2}},
176     {"2880", {512, 2, 1, 2, 240, 5760, 0xf0, 9, 36, 2}}
177 };
178 
179 static u_int8_t bootcode[] = {
180     0xfa,			/* cli		    */
181     0x31, 0xc0, 		/* xor	   ax,ax    */
182     0x8e, 0xd0, 		/* mov	   ss,ax    */
183     0xbc, 0x00, 0x7c,		/* mov	   sp,7c00h */
184     0xfb,			/* sti		    */
185     0x8e, 0xd8, 		/* mov	   ds,ax    */
186     0xe8, 0x00, 0x00,		/* call    $ + 3    */
187     0x5e,			/* pop	   si	    */
188     0x83, 0xc6, 0x19,		/* add	   si,+19h  */
189     0xbb, 0x07, 0x00,		/* mov	   bx,0007h */
190     0xfc,			/* cld		    */
191     0xac,			/* lodsb	    */
192     0x84, 0xc0, 		/* test    al,al    */
193     0x74, 0x06, 		/* jz	   $ + 8    */
194     0xb4, 0x0e, 		/* mov	   ah,0eh   */
195     0xcd, 0x10, 		/* int	   10h	    */
196     0xeb, 0xf5, 		/* jmp	   $ - 9    */
197     0x30, 0xe4, 		/* xor	   ah,ah    */
198     0xcd, 0x16, 		/* int	   16h	    */
199     0xcd, 0x19, 		/* int	   19h	    */
200     0x0d, 0x0a,
201     'N', 'o', 'n', '-', 's', 'y', 's', 't',
202     'e', 'm', ' ', 'd', 'i', 's', 'k',
203     0x0d, 0x0a,
204     'P', 'r', 'e', 's', 's', ' ', 'a', 'n',
205     'y', ' ', 'k', 'e', 'y', ' ', 't', 'o',
206     ' ', 'r', 'e', 'b', 'o', 'o', 't',
207     0x0d, 0x0a,
208     0
209 };
210 
211 static void check_mounted(const char *, mode_t);
212 static void getstdfmt(const char *, struct bpb *);
213 static void getdiskinfo(int, const char *, const char *, int,
214 			struct bpb *);
215 static void print_bpb(struct bpb *);
216 static u_int ckgeom(const char *, u_int, const char *);
217 static u_int argtou(const char *, u_int, u_int, const char *);
218 static int oklabel(const char *);
219 static void mklabel(u_int8_t *, const char *);
220 static void setstr(u_int8_t *, const char *, size_t);
221 static __dead void usage(void);
222 
223 /*
224  * Construct a FAT12, FAT16, or FAT32 file system.
225  */
226 int
main(int argc,char * argv[])227 main(int argc, char *argv[])
228 {
229     static char opts[] = "NB:F:I:L:O:S:a:b:c:e:f:h:i:k:m:n:o:qr:s:t:u:";
230     static const char *opt_B, *opt_L, *opt_O, *opt_f;
231     static u_int opt_F, opt_I, opt_S, opt_a, opt_b, opt_c, opt_e;
232     static u_int opt_h, opt_i, opt_k, opt_m, opt_n, opt_o, opt_r;
233     static u_int opt_s, opt_u;
234     static int opt_N;
235     static int Iflag, mflag, oflag;
236     char buf[PATH_MAX];
237     struct stat sb;
238     struct timeval tv;
239     struct bpb bpb;
240     struct tm *tm;
241     struct bs *bs;
242     struct bsbpb *bsbpb;
243     struct bsxbpb *bsxbpb;
244     struct bsx *bsx;
245     struct de *de;
246     u_int8_t *img;
247     const char *dtype, *bname;
248     char *sname, *fname;
249     ssize_t n;
250     time_t now;
251     u_int fat, bss, rds, cls, dir, lsn, x, x1, x2;
252     int ch, fd, fd1;
253 
254     if (pledge("stdio rpath wpath disklabel", NULL) == -1)
255 	err(1, "pledge");
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 	    opt_F = strtonum(optarg, 1, INT_MAX, NULL);
267 	    if (!(opt_F == 12 || opt_F == 16 || opt_F == 32))
268 		errx(1, "%s: bad FAT type", optarg);
269 	    break;
270 	case 'I':
271 	    opt_I = argto4(optarg, 0, "volume ID");
272 	    Iflag = 1;
273 	    break;
274 	case 'L':
275 	    if (!oklabel(optarg))
276 		errx(1, "%s: bad volume label", optarg);
277 	    opt_L = optarg;
278 	    break;
279 	case 'O':
280 	    if (strlen(optarg) > 8)
281 		errx(1, "%s: bad OEM string", optarg);
282 	    opt_O = optarg;
283 	    break;
284 	case 'S':
285 	    opt_S = argto2(optarg, 1, "bytes/sector");
286 	    break;
287 	case 'a':
288 	    opt_a = argto4(optarg, 1, "sectors/FAT");
289 	    break;
290 	case 'b':
291 	    opt_b = argtox(optarg, 1, "block size");
292 	    opt_c = 0;
293 	    break;
294 	case 'c':
295 	    opt_c = argto1(optarg, 1, "sectors/cluster");
296 	    opt_b = 0;
297 	    break;
298 	case 'e':
299 	    opt_e = argto2(optarg, 1, "directory entries");
300 	    break;
301 	case 'f':
302 	    opt_f = optarg;
303 	    break;
304 	case 'h':
305 	    opt_h = argto2(optarg, 1, "drive heads");
306 	    break;
307 	case 'i':
308 	    opt_i = argto2(optarg, 1, "info sector");
309 	    break;
310 	case 'k':
311 	    opt_k = argto2(optarg, 1, "backup sector");
312 	    break;
313 	case 'm':
314 	    opt_m = argto1(optarg, 0, "media descriptor");
315 	    mflag = 1;
316 	    break;
317 	case 'n':
318 	    opt_n = argto1(optarg, 1, "number of FATs");
319 	    break;
320 	case 'o':
321 	    opt_o = argto4(optarg, 0, "hidden sectors");
322 	    oflag = 1;
323 	    break;
324 	case 'q':			/* Compat with newfs -q */
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 't':			/* Compat with newfs -t */
333 	    break;
334 	case 'u':
335 	    opt_u = argto2(optarg, 1, "sectors/track");
336 	    break;
337 	default:
338 	    usage();
339 	}
340     argc -= optind;
341     argv += optind;
342     if (argc < 1 || argc > 2)
343 	usage();
344     sname = *argv++;
345     dtype = *argv;
346     if ((fd = opendev(sname, opt_N ? O_RDONLY : O_RDWR, 0, &fname)) == -1 ||
347 	fstat(fd, &sb))
348 	err(1, "%s", fname);
349     if (!opt_N)
350 	check_mounted(fname, sb.st_mode);
351     if (S_ISBLK(sb.st_mode))
352 	errx(1, "%s: block device", fname);
353     if (!S_ISCHR(sb.st_mode))
354 	warnx("warning: %s is not a character device", fname);
355     memset(&bpb, 0, sizeof(bpb));
356     if (opt_f) {
357 	getstdfmt(opt_f, &bpb);
358 	bpb.bsec = bpb.sec;
359 	bpb.sec = 0;
360 	bpb.bspf = bpb.spf;
361 	bpb.spf = 0;
362     }
363     if (opt_h)
364 	bpb.hds = opt_h;
365     if (opt_u)
366 	bpb.spt = opt_u;
367     if (opt_S)
368 	bpb.bps = opt_S;
369     if (opt_s)
370 	bpb.bsec = opt_s;
371     if (oflag)
372 	bpb.hid = opt_o;
373     if (!(opt_f || (opt_h && opt_u && opt_S && opt_s && oflag)))
374 	getdiskinfo(fd, fname, dtype, oflag, &bpb);
375     if (!powerof2(bpb.bps))
376 	errx(1, "bytes/sector (%u) is not a power of 2", bpb.bps);
377     if (bpb.bps < MINBPS)
378 	errx(1, "bytes/sector (%u) is too small; minimum is %u",
379 	     bpb.bps, MINBPS);
380     if (!(fat = opt_F)) {
381 	if (opt_f)
382 	    fat = 12;
383 	else if (!opt_e && (opt_i || opt_k))
384 	    fat = 32;
385     }
386     if ((fat == 32 && opt_e) || (fat != 32 && (opt_i || opt_k)))
387 	errx(1, "-%c is not a legal FAT%s option",
388 	     fat == 32 ? 'e' : opt_i ? 'i' : 'k',
389 	     fat == 32 ? "32" : "12/16");
390     if (opt_f && fat == 32)
391 	bpb.rde = 0;
392     if (opt_b) {
393 	if (!powerof2(opt_b))
394 	    errx(1, "block size (%u) is not a power of 2", opt_b);
395 	if (opt_b < bpb.bps)
396 	    errx(1, "block size (%u) is too small; minimum is %u",
397 		 opt_b, bpb.bps);
398 	if (opt_b > bpb.bps * MAXSPC)
399 	    errx(1, "block size (%u) is too large; maximum is %u",
400 		 opt_b, bpb.bps * MAXSPC);
401 	bpb.spc = opt_b / bpb.bps;
402     }
403     if (opt_c) {
404 	if (!powerof2(opt_c))
405 	    errx(1, "sectors/cluster (%u) is not a power of 2", opt_c);
406 	bpb.spc = opt_c;
407     }
408     if (opt_r)
409 	bpb.res = opt_r;
410     if (opt_n) {
411 	if (opt_n > MAXNFT)
412 	    errx(1, "number of FATs (%u) is too large; maximum is %u",
413 		 opt_n, MAXNFT);
414 	bpb.nft = opt_n;
415     }
416     if (opt_e)
417 	bpb.rde = opt_e;
418     if (mflag) {
419 	if (opt_m < 0xf0)
420 	    errx(1, "illegal media descriptor (%#x)", opt_m);
421 	bpb.mid = opt_m;
422     }
423     if (opt_a)
424 	bpb.bspf = opt_a;
425     if (opt_i)
426 	bpb.infs = opt_i;
427     if (opt_k)
428 	bpb.bkbs = opt_k;
429     bss = 1;
430     bname = NULL;
431     fd1 = -1;
432     if (opt_B) {
433 	bname = opt_B;
434 	if (!strchr(bname, '/')) {
435 	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
436 	    if (!(bname = strdup(buf)))
437 		err(1, NULL);
438 	}
439 	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb))
440 	    err(1, "%s", bname);
441 	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bps ||
442 	    sb.st_size < bpb.bps || sb.st_size > bpb.bps * MAXU16)
443 	    errx(1, "%s: inappropriate file type or format", bname);
444 	bss = sb.st_size / bpb.bps;
445     }
446     if (!bpb.nft)
447 	bpb.nft = 2;
448     if (!fat) {
449 	if (bpb.bsec < (bpb.res ? bpb.res : bss) +
450 	    howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
451 		    ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
452 	    bpb.nft +
453 	    howmany(bpb.rde ? bpb.rde : DEFRDE,
454 		    bpb.bps / sizeof(struct de)) +
455 	    (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
456 	    (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
457 	    fat = 12;
458 	else if (bpb.rde || bpb.bsec <
459 		 (bpb.res ? bpb.res : bss) +
460 		 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
461 		 howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
462 		 (MAXCLS16 + 1) *
463 		 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
464 	    fat = 16;
465 	else
466 	    fat = 32;
467     }
468     x = bss;
469     if (fat == 32) {
470 	if (!bpb.infs) {
471 	    if (x == MAXU16 || x == bpb.bkbs)
472 		errx(1, "no room for info sector");
473 	    bpb.infs = x;
474 	}
475 	if (bpb.infs != MAXU16 && x <= bpb.infs)
476 	    x = bpb.infs + 1;
477 	if (!bpb.bkbs) {
478 	    if (x == MAXU16)
479 		errx(1, "no room for backup sector");
480 	    bpb.bkbs = x;
481 	} else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs)
482 	    errx(1, "backup sector would overwrite info sector");
483 	if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
484 	    x = bpb.bkbs + 1;
485     }
486     if (!bpb.res)
487 	bpb.res = fat == 32 ? MAXIMUM(x, MAXIMUM(16384 / bpb.bps, 4)) : x;
488     else if (bpb.res < x)
489 	errx(1, "too few reserved sectors");
490     if (fat != 32 && !bpb.rde)
491 	bpb.rde = DEFRDE;
492     rds = howmany(bpb.rde, bpb.bps / sizeof(struct de));
493     if (!bpb.spc)
494 	for (bpb.spc = howmany(fat == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
495 	     bpb.spc < MAXSPC &&
496 	     bpb.res +
497 	     howmany((RESFTE + maxcls(fat)) * (fat / BPN),
498 		     bpb.bps * NPB) * bpb.nft +
499 	     rds +
500 	     (u_int64_t)(maxcls(fat) + 1) * bpb.spc <= bpb.bsec;
501 	     bpb.spc <<= 1);
502     if (fat != 32 && bpb.bspf > MAXU16)
503 	errx(1, "too many sectors/FAT for FAT12/16");
504     x1 = bpb.res + rds;
505     x = bpb.bspf ? bpb.bspf : 1;
506     if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec)
507 	errx(1, "meta data exceeds file system size");
508     x1 += x * bpb.nft;
509     x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
510 	(bpb.spc * bpb.bps * NPB + fat / BPN * bpb.nft);
511     x2 = howmany((RESFTE + MINIMUM(x, maxcls(fat))) * (fat / BPN),
512 		 bpb.bps * NPB);
513     if (!bpb.bspf) {
514 	bpb.bspf = x2;
515 	x1 += (bpb.bspf - 1) * bpb.nft;
516     }
517     cls = (bpb.bsec - x1) / bpb.spc;
518     x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (fat / BPN) - RESFTE;
519     if (cls > x)
520 	cls = x;
521     if (bpb.bspf < x2)
522 	warnx("warning: sectors/FAT limits file system to %u clusters",
523 	      cls);
524     if (cls < mincls(fat))
525 	errx(1, "%u clusters too few clusters for FAT%u, need %u", cls, fat,
526 	    mincls(fat));
527     if (cls > maxcls(fat)) {
528 	cls = maxcls(fat);
529 	bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
530 	warnx("warning: FAT type limits file system to %u sectors",
531 	      bpb.bsec);
532     }
533     printf("%s: %u sector%s in %u FAT%u cluster%s "
534 	   "(%u bytes/cluster)\n", fname, cls * bpb.spc,
535 	   cls * bpb.spc == 1 ? "" : "s", cls, fat,
536 	   cls == 1 ? "" : "s", bpb.bps * bpb.spc);
537     if (!bpb.mid)
538 	bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
539     if (fat == 32)
540 	bpb.rdcl = RESFTE;
541     if (bpb.hid + bpb.bsec <= MAXU16) {
542 	bpb.sec = bpb.bsec;
543 	bpb.bsec = 0;
544     }
545     if (fat != 32) {
546 	bpb.spf = bpb.bspf;
547 	bpb.bspf = 0;
548     }
549     print_bpb(&bpb);
550     if (!opt_N) {
551 	gettimeofday(&tv, NULL);
552 	now = tv.tv_sec;
553 	if ((tm = localtime(&now)) == NULL)
554 		errx(1, "Invalid time");
555 
556 	if (!(img = malloc(bpb.bps)))
557 	    err(1, NULL);
558 	dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;
559 	for (lsn = 0; lsn < dir + (fat == 32 ? bpb.spc : rds); lsn++) {
560 	    x = lsn;
561 	    if (opt_B &&
562 		fat == 32 && bpb.bkbs != MAXU16 &&
563 		bss <= bpb.bkbs && x >= bpb.bkbs) {
564 		x -= bpb.bkbs;
565 		if (!x && lseek(fd1, 0, SEEK_SET))
566 		    err(1, "%s", bname);
567 	    }
568 	    if (opt_B && x < bss) {
569 		if ((n = read(fd1, img, bpb.bps)) == -1)
570 		    err(1, "%s", bname);
571 		if (n != bpb.bps)
572 		    errx(1, "%s: can't read sector %u", bname, x);
573 	    } else
574 		memset(img, 0, bpb.bps);
575 	    if (!lsn ||
576 	      (fat == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
577 		x1 = sizeof(struct bs);
578 		bsbpb = (struct bsbpb *)(img + x1);
579 		mk2(bsbpb->bps, bpb.bps);
580 		mk1(bsbpb->spc, bpb.spc);
581 		mk2(bsbpb->res, bpb.res);
582 		mk1(bsbpb->nft, bpb.nft);
583 		mk2(bsbpb->rde, bpb.rde);
584 		mk2(bsbpb->sec, bpb.sec);
585 		mk1(bsbpb->mid, bpb.mid);
586 		mk2(bsbpb->spf, bpb.spf);
587 		mk2(bsbpb->spt, bpb.spt);
588 		mk2(bsbpb->hds, bpb.hds);
589 		mk4(bsbpb->hid, bpb.hid);
590 		mk4(bsbpb->bsec, bpb.bsec);
591 		x1 += sizeof(struct bsbpb);
592 		if (fat == 32) {
593 		    bsxbpb = (struct bsxbpb *)(img + x1);
594 		    mk4(bsxbpb->bspf, bpb.bspf);
595 		    mk2(bsxbpb->xflg, 0);
596 		    mk2(bsxbpb->vers, 0);
597 		    mk4(bsxbpb->rdcl, bpb.rdcl);
598 		    mk2(bsxbpb->infs, bpb.infs);
599 		    mk2(bsxbpb->bkbs, bpb.bkbs);
600 		    x1 += sizeof(struct bsxbpb);
601 		}
602 		bsx = (struct bsx *)(img + x1);
603 		mk1(bsx->sig, 0x29);
604 		if (Iflag)
605 		    x = opt_I;
606 		else
607 		    x = (((u_int)(1 + tm->tm_mon) << 8 |
608 			  (u_int)tm->tm_mday) +
609 			 ((u_int)tm->tm_sec << 8 |
610 			  (u_int)(tv.tv_usec / 10))) << 16 |
611 			((u_int)(1900 + tm->tm_year) +
612 			 ((u_int)tm->tm_hour << 8 |
613 			  (u_int)tm->tm_min));
614 		mk4(bsx->volid, x);
615 		mklabel(bsx->label, opt_L ? opt_L : "NO NAME");
616 		snprintf(buf, sizeof buf, "FAT%u", fat);
617 		setstr(bsx->type, buf, sizeof(bsx->type));
618 		if (!opt_B) {
619 		    x1 += sizeof(struct bsx);
620 		    bs = (struct bs *)img;
621 		    mk1(bs->jmp[0], 0xeb);
622 		    mk1(bs->jmp[1], x1 - 2);
623 		    mk1(bs->jmp[2], 0x90);
624 		    setstr(bs->oem, opt_O ? opt_O : "BSD  4.4",
625 			   sizeof(bs->oem));
626 		    memcpy(img + x1, bootcode, sizeof(bootcode));
627 		    mk2(img + MINBPS - 2, DOSMAGIC);
628 		}
629 	    } else if (fat == 32 && bpb.infs != MAXU16 &&
630 		       (lsn == bpb.infs ||
631 			(bpb.bkbs != MAXU16 &&
632 			 lsn == bpb.bkbs + bpb.infs))) {
633 		mk4(img, 0x41615252);
634 		mk4(img + MINBPS - 28, 0x61417272);
635 		mk4(img + MINBPS - 24, 0xffffffff);
636 		mk4(img + MINBPS - 20, 0xffffffff);
637 		mk2(img + MINBPS - 2, DOSMAGIC);
638 	    } else if (lsn >= bpb.res && lsn < dir &&
639 		       !((lsn - bpb.res) %
640 			 (bpb.spf ? bpb.spf : bpb.bspf))) {
641 		mk1(img[0], bpb.mid);
642 		for (x = 1; x < fat * (fat == 32 ? 3 : 2) / 8; x++)
643 		    mk1(img[x], fat == 32 && x % 4 == 3 ? 0x0f : 0xff);
644 	    } else if (lsn == dir && opt_L) {
645 		de = (struct de *)img;
646 		mklabel(de->namext, opt_L);
647 		mk1(de->attr, 050);
648 		x = (u_int)tm->tm_hour << 11 |
649 		    (u_int)tm->tm_min << 5 |
650 		    (u_int)tm->tm_sec >> 1;
651 		mk2(de->time, x);
652 		x = (u_int)(tm->tm_year - 80) << 9 |
653 		    (u_int)(tm->tm_mon + 1) << 5 |
654 		    (u_int)tm->tm_mday;
655 		mk2(de->date, x);
656 	    }
657 	    if ((n = write(fd, img, bpb.bps)) == -1)
658 		err(1, "%s", fname);
659 	    if (n != bpb.bps)
660 		errx(1, "%s: can't write sector %u", fname, lsn);
661 	}
662     }
663     return 0;
664 }
665 
666 /*
667  * Exit with error if file system is mounted.
668  */
669 static void
check_mounted(const char * fname,mode_t mode)670 check_mounted(const char *fname, mode_t mode)
671 {
672     struct statfs *mp;
673     const char *s1, *s2;
674     size_t len;
675     int n, r;
676 
677     if (!(n = getmntinfo(&mp, MNT_NOWAIT)))
678 	err(1, "getmntinfo");
679     len = sizeof(_PATH_DEV) - 1;
680     s1 = fname;
681     if (!strncmp(s1, _PATH_DEV, len))
682 	s1 += len;
683     r = S_ISCHR(mode) && s1 != fname && *s1 == 'r';
684     for (; n--; mp++) {
685 	s2 = mp->f_mntfromname;
686 	if (!strncmp(s2, _PATH_DEV, len))
687 	    s2 += len;
688 	if ((r && s2 != mp->f_mntfromname && !strcmp(s1 + 1, s2)) ||
689 	    !strcmp(s1, s2))
690 	    errx(1, "%s is mounted on %s", fname, mp->f_mntonname);
691     }
692 }
693 
694 /*
695  * Get a standard format.
696  */
697 static void
getstdfmt(const char * fmt,struct bpb * bpb)698 getstdfmt(const char *fmt, struct bpb *bpb)
699 {
700     u_int x, i;
701 
702     x = sizeof(stdfmt) / sizeof(stdfmt[0]);
703     for (i = 0; i < x && strcmp(fmt, stdfmt[i].name); i++);
704     if (i == x)
705 	errx(1, "%s: unknown standard format", fmt);
706     *bpb = stdfmt[i].bpb;
707 }
708 
709 /*
710  * Get disk slice, partition, and geometry information.
711  */
712 static void
getdiskinfo(int fd,const char * fname,const char * dtype,int oflag,struct bpb * bpb)713 getdiskinfo(int fd, const char *fname, const char *dtype, int oflag,
714 	    struct bpb *bpb)
715 {
716     struct disklabel dl, *lp;
717     const char *s1, *s2;
718     int part, i;
719 
720     part = -1;
721     s1 = fname;
722     if ((s2 = strrchr(s1, '/')))
723 	s1 = s2 + 1;
724     for (s2 = s1; *s2 && !isdigit((unsigned char)*s2); s2++);
725     if (!*s2 || s2 == s1)
726 	s2 = NULL;
727     else
728 	while (isdigit((unsigned char)*++s2));
729     s1 = s2;
730     if (s2 && *s2 >= 'a' && *s2 <= 'a' + MAXPARTITIONS - 1) {
731 	part = *s2++ - 'a';
732     }
733     if (!s2 || (*s2 && *s2 != '.'))
734 	errx(1, "%s: can't figure out partition info", fname);
735     if ((((!oflag && part != -1) || !bpb->bsec)) ||
736 	!bpb->bps || !bpb->spt || !bpb->hds) {
737 	lp = &dl;
738 	i = ioctl(fd, DIOCGDINFO, lp);
739 	if (i == -1) {
740 	    if (!dtype) {
741 		warn("ioctl (GDINFO)");
742 		errx(1, "%s: can't read disk label; "
743 		     "disk type must be specified", fname);
744 	    } else if (!(lp = getdiskbyname(dtype)))
745 		errx(1, "%s: unknown disk type", dtype);
746 	}
747 	if (part == -1)
748 	    part = RAW_PART;
749 	if (part >= lp->d_npartitions ||
750 	    !DL_GETPSIZE(&lp->d_partitions[part]))
751 	    errx(1, "%s: partition is unavailable", fname);
752 	if (!oflag && part != -1)
753 	    bpb->hid += DL_GETPOFFSET(&lp->d_partitions[part]);
754 	if (!bpb->bsec)
755 	    bpb->bsec = DL_GETPSIZE(&lp->d_partitions[part]);
756 	if (!bpb->bps)
757 	    bpb->bps = ckgeom(fname, lp->d_secsize, "bytes/sector");
758 	if (!bpb->spt)
759 	    bpb->spt = ckgeom(fname, lp->d_nsectors, "sectors/track");
760 	if (!bpb->hds)
761 	    bpb->hds = ckgeom(fname, lp->d_ntracks, "drive heads");
762 	if (bpb->spt > 63) {
763 	    bpb->hds = bpb->hds * bpb->spt / 63;
764 	    bpb->spt = 63;
765 	}
766     }
767 }
768 
769 /*
770  * Print out BPB values.
771  */
772 static void
print_bpb(struct bpb * bpb)773 print_bpb(struct bpb *bpb)
774 {
775     printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
776 	   bpb->nft);
777     if (bpb->rde)
778 	printf(" rde=%u", bpb->rde);
779     if (bpb->sec)
780 	printf(" sec=%u", bpb->sec);
781     printf(" mid=%#x", bpb->mid);
782     if (bpb->spf)
783 	printf(" spf=%u", bpb->spf);
784     printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
785     if (bpb->bsec)
786 	printf(" bsec=%u", bpb->bsec);
787     if (!bpb->spf) {
788 	printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
789 	printf(" infs=");
790 	printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
791 	printf(" bkbs=");
792 	printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
793     }
794     printf("\n");
795 }
796 
797 /*
798  * Check a disk geometry value.
799  */
800 static u_int
ckgeom(const char * fname,u_int val,const char * msg)801 ckgeom(const char *fname, u_int val, const char *msg)
802 {
803     if (!val)
804 	errx(1, "%s: no default %s", fname, msg);
805     if (val > MAXU16)
806 	errx(1, "%s: illegal %s", fname, msg);
807     return val;
808 }
809 
810 /*
811  * Convert and check a numeric option argument.
812  */
813 static u_int
argtou(const char * arg,u_int lo,u_int hi,const char * msg)814 argtou(const char *arg, u_int lo, u_int hi, const char *msg)
815 {
816     char *s;
817     u_long x;
818 
819     errno = 0;
820     x = strtoul(arg, &s, 0);
821     if (errno || !*arg || *s || x < lo || x > hi)
822 	errx(1, "%s: bad %s", arg, msg);
823     return x;
824 }
825 
826 /*
827  * Check a volume label.
828  */
829 static int
oklabel(const char * src)830 oklabel(const char *src)
831 {
832     int c = 0, i;
833 
834     for (i = 0; i <= 11; i++) {
835 	c = (u_char)*src++;
836 	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
837 	    break;
838     }
839     return i && !c;
840 }
841 
842 /*
843  * Make a volume label.
844  */
845 static void
mklabel(u_int8_t * dest,const char * src)846 mklabel(u_int8_t *dest, const char *src)
847 {
848     int c, i;
849 
850     for (i = 0; i < 11; i++) {
851 	c = *src ? toupper((unsigned char)*src++) : ' ';
852 	*dest++ = !i && c == '\xe5' ? 5 : c;
853     }
854 }
855 
856 /*
857  * Copy string, padding with spaces.
858  */
859 static void
setstr(u_int8_t * dest,const char * src,size_t len)860 setstr(u_int8_t *dest, const char *src, size_t len)
861 {
862     while (len--)
863 	*dest++ = *src ? *src++ : ' ';
864 }
865 
866 /*
867  * Print usage message.
868  */
869 static __dead void
usage(void)870 usage(void)
871 {
872 	extern const char	*__progname;
873 
874 	fprintf(stderr, "usage: %s "
875 	    "[-N] [-a FAT-size] [-B boot] [-b block-size]\n"
876 	    "\t[-c cluster-size] [-e dirents] [-F FAT-type] [-f format]\n"
877 	    "\t[-h heads] [-I volid] [-i info] [-k backup] [-L label]\n"
878 	    "\t[-m media] [-n FATs] [-O OEM] [-o hidden] [-r reserved]\n"
879 	    "\t[-S sector-size] [-s total] [-u track-size] special\n"
880 	    "\t[disktype]\n",
881 	    __progname);
882 	exit(1);
883 }
884