1 /* $OpenBSD: mkfs_msdos.c,v 1.7 2022/02/28 16:17:37 krw Exp $ */
2 /* $NetBSD: mkfs_msdos.c,v 1.10 2016/04/03 11:00:13 mlelstv Exp $ */
3
4 /*
5 * Copyright (c) 1998 Robert Nordier
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
19 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY
22 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
24 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
26 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
27 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
28 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include <sys/param.h> /* powerof2 */
32 #include <sys/types.h>
33 #include <sys/stat.h>
34 #include <sys/time.h>
35
36 #include <ctype.h>
37 #include <err.h>
38 #include <errno.h>
39 #include <fcntl.h>
40 #include <paths.h>
41 #include <stdio.h>
42 #include <stdint.h>
43 #include <stdlib.h>
44 #include <limits.h>
45 #include <string.h>
46 #include <time.h>
47 #include <unistd.h>
48 #include <signal.h>
49
50 #include <util.h>
51
52 #include "makefs.h"
53 #include "msdos/mkfs_msdos.h"
54
55 #define MAXU16 0xffff /* maximum unsigned 16-bit quantity */
56 #define BPN 4 /* bits per nibble */
57 #define NPB 2 /* nibbles per byte */
58
59 #define DOSMAGIC 0xaa55 /* DOS magic number */
60 #define MINBPS 512 /* minimum bytes per sector */
61 #define MAXSPC 128 /* maximum sectors per cluster */
62 #define MAXNFT 16 /* maximum number of FATs */
63 #define DEFBLK 4096 /* default block size */
64 #define DEFBLK16 2048 /* default block size FAT16 */
65 #define DEFRDE 512 /* default root directory entries */
66 #define RESFTE 2 /* reserved FAT entries */
67 #define MINCLS12 1 /* minimum FAT12 clusters */
68 #define MINCLS16 0xff5 /* minimum FAT16 clusters */
69 #define MINCLS32 0xfff5 /* minimum FAT32 clusters */
70 #define MAXCLS12 0xff4 /* maximum FAT12 clusters */
71 #define MAXCLS16 0xfff4 /* maximum FAT16 clusters */
72 #define MAXCLS32 0xffffff4 /* maximum FAT32 clusters */
73
74 #define mincls(fat_type) ((fat_type) == 12 ? MINCLS12 : \
75 (fat_type) == 16 ? MINCLS16 : \
76 MINCLS32)
77
78 #define maxcls(fat_type) ((fat_type) == 12 ? MAXCLS12 : \
79 (fat_type) == 16 ? MAXCLS16 : \
80 MAXCLS32)
81
82 #define mk1(p, x) \
83 (p) = (u_int8_t)(x)
84
85 #define mk2(p, x) \
86 (p)[0] = (u_int8_t)(x), \
87 (p)[1] = (u_int8_t)((x) >> 010)
88
89 #define mk4(p, x) \
90 (p)[0] = (u_int8_t)(x), \
91 (p)[1] = (u_int8_t)((x) >> 010), \
92 (p)[2] = (u_int8_t)((x) >> 020), \
93 (p)[3] = (u_int8_t)((x) >> 030)
94
95 struct bs {
96 u_int8_t jmp[3]; /* bootstrap entry point */
97 u_int8_t oem[8]; /* OEM name and version */
98 };
99
100 struct bsbpb {
101 u_int8_t bps[2]; /* bytes per sector */
102 u_int8_t spc; /* sectors per cluster */
103 u_int8_t res[2]; /* reserved sectors */
104 u_int8_t nft; /* number of FATs */
105 u_int8_t rde[2]; /* root directory entries */
106 u_int8_t sec[2]; /* total sectors */
107 u_int8_t mid; /* media descriptor */
108 u_int8_t spf[2]; /* sectors per FAT */
109 u_int8_t spt[2]; /* sectors per track */
110 u_int8_t hds[2]; /* drive heads */
111 u_int8_t hid[4]; /* hidden sectors */
112 u_int8_t bsec[4]; /* big total sectors */
113 };
114
115 struct bsxbpb {
116 u_int8_t bspf[4]; /* big sectors per FAT */
117 u_int8_t xflg[2]; /* FAT control flags */
118 u_int8_t vers[2]; /* file system version */
119 u_int8_t rdcl[4]; /* root directory start cluster */
120 u_int8_t infs[2]; /* file system info sector */
121 u_int8_t bkbs[2]; /* backup boot sector */
122 u_int8_t rsvd[12]; /* reserved */
123 };
124
125 struct bsx {
126 u_int8_t drv; /* drive number */
127 u_int8_t rsvd; /* reserved */
128 u_int8_t sig; /* extended boot signature */
129 u_int8_t volid[4]; /* volume ID number */
130 u_int8_t label[11]; /* volume label */
131 u_int8_t type[8]; /* file system type */
132 };
133
134 struct de {
135 u_int8_t namext[11]; /* name and extension */
136 u_int8_t attr; /* attributes */
137 u_int8_t rsvd[10]; /* reserved */
138 u_int8_t time[2]; /* creation time */
139 u_int8_t date[2]; /* creation date */
140 u_int8_t clus[2]; /* starting cluster */
141 u_int8_t size[4]; /* size */
142 };
143
144 struct bpb {
145 u_int bps; /* bytes per sector */
146 u_int spc; /* sectors per cluster */
147 u_int res; /* reserved sectors */
148 u_int nft; /* number of FATs */
149 u_int rde; /* root directory entries */
150 u_int sec; /* total sectors */
151 u_int mid; /* media descriptor */
152 u_int spf; /* sectors per FAT */
153 u_int spt; /* sectors per track */
154 u_int hds; /* drive heads */
155 u_int hid; /* hidden sectors */
156 u_int bsec; /* big total sectors */
157 u_int bspf; /* big sectors per FAT */
158 u_int rdcl; /* root directory start cluster */
159 u_int infs; /* file system info sector */
160 u_int bkbs; /* backup boot sector */
161 };
162
163 #define INIT(a, b, c, d, e, f, g, h, i, j) \
164 { .bps = a, .spc = b, .res = c, .nft = d, .rde = e, \
165 .sec = f, .mid = g, .spf = h, .spt = i, .hds = j, }
166 static struct {
167 const char *name;
168 struct bpb bpb;
169 } stdfmt[] = {
170 {"160", INIT(512, 1, 1, 2, 64, 320, 0xfe, 1, 8, 1)},
171 {"180", INIT(512, 1, 1, 2, 64, 360, 0xfc, 2, 9, 1)},
172 {"320", INIT(512, 2, 1, 2, 112, 640, 0xff, 1, 8, 2)},
173 {"360", INIT(512, 2, 1, 2, 112, 720, 0xfd, 2, 9, 2)},
174 {"640", INIT(512, 2, 1, 2, 112, 1280, 0xfb, 2, 8, 2)},
175 {"720", INIT(512, 2, 1, 2, 112, 1440, 0xf9, 3, 9, 2)},
176 {"1200", INIT(512, 1, 1, 2, 224, 2400, 0xf9, 7, 15, 2)},
177 {"1232", INIT(1024,1, 1, 2, 192, 1232, 0xfe, 2, 8, 2)},
178 {"1440", INIT(512, 1, 1, 2, 224, 2880, 0xf0, 9, 18, 2)},
179 {"2880", INIT(512, 2, 1, 2, 240, 5760, 0xf0, 9, 36, 2)}
180 };
181
182 static u_int8_t bootcode[] = {
183 0xfa, /* cli */
184 0x31, 0xc0, /* xor ax,ax */
185 0x8e, 0xd0, /* mov ss,ax */
186 0xbc, 0x00, 0x7c, /* mov sp,7c00h */
187 0xfb, /* sti */
188 0x8e, 0xd8, /* mov ds,ax */
189 0xe8, 0x00, 0x00, /* call $ + 3 */
190 0x5e, /* pop si */
191 0x83, 0xc6, 0x19, /* add si,+19h */
192 0xbb, 0x07, 0x00, /* mov bx,0007h */
193 0xfc, /* cld */
194 0xac, /* lodsb */
195 0x84, 0xc0, /* test al,al */
196 0x74, 0x06, /* jz $ + 8 */
197 0xb4, 0x0e, /* mov ah,0eh */
198 0xcd, 0x10, /* int 10h */
199 0xeb, 0xf5, /* jmp $ - 9 */
200 0x30, 0xe4, /* xor ah,ah */
201 0xcd, 0x16, /* int 16h */
202 0xcd, 0x19, /* int 19h */
203 0x0d, 0x0a,
204 'N', 'o', 'n', '-', 's', 'y', 's', 't',
205 'e', 'm', ' ', 'd', 'i', 's', 'k',
206 0x0d, 0x0a,
207 'P', 'r', 'e', 's', 's', ' ', 'a', 'n',
208 'y', ' ', 'k', 'e', 'y', ' ', 't', 'o',
209 ' ', 'r', 'e', 'b', 'o', 'o', 't',
210 0x0d, 0x0a,
211 0
212 };
213
214 static int got_siginfo = 0; /* received a SIGINFO */
215
216 static int getstdfmt(const char *, struct bpb *);
217 static int getbpbinfo(int, const char *, const char *, int, struct bpb *, int);
218 static void print_bpb(struct bpb *);
219 static int ckgeom(const char *, u_int, const char *);
220 static int oklabel(const char *);
221 static void mklabel(u_int8_t *, const char *);
222 static void setstr(u_int8_t *, const char *, size_t);
223 static void infohandler(int sig);
224
225 int
mkfs_msdos(const char * fname,const char * dtype,const struct msdos_options * op)226 mkfs_msdos(const char *fname, const char *dtype, const struct msdos_options *op)
227 {
228 char buf[PATH_MAX];
229 struct stat sb;
230 struct timeval tv;
231 struct bpb bpb;
232 struct tm *tm;
233 struct bs *bs;
234 struct bsbpb *bsbpb;
235 struct bsxbpb *bsxbpb;
236 struct bsx *bsx;
237 struct de *de;
238 u_int8_t *img;
239 const char *bname;
240 ssize_t n;
241 time_t now;
242 u_int bss, rds, cls, dir, lsn, x, x1, x2;
243 int ch, fd, fd1;
244 struct msdos_options o = *op;
245 int oflags = O_RDWR | O_CREAT;
246
247 if (o.block_size && o.sectors_per_cluster) {
248 warnx("Cannot specify both block size and sectors per cluster");
249 return -1;
250 }
251 if (o.OEM_string && strlen(o.OEM_string) > 8) {
252 warnx("%s: bad OEM string", o.OEM_string);
253 return -1;
254 }
255 if (o.create_size) {
256 if (o.offset == 0)
257 oflags |= O_TRUNC;
258 fd = open(fname, oflags, 0644);
259 if (fd == -1) {
260 warnx("failed to create %s", fname);
261 return -1;
262 }
263 (void)lseek(fd, o.create_size - 1, SEEK_SET);
264 if (write(fd, "\0", 1) != 1) {
265 warn("failed to set file size");
266 return -1;
267 }
268 (void)lseek(fd, 0, SEEK_SET);
269 } else if ((fd = open(fname, O_RDWR)) == -1 ||
270 fstat(fd, &sb)) {
271 warn("%s", fname);
272 return -1;
273 }
274 if (!S_ISCHR(sb.st_mode) && !o.create_size) {
275 warnx("warning, %s is not a character device", fname);
276 return -1;
277 }
278 if (o.offset && o.offset != lseek(fd, o.offset, SEEK_SET)) {
279 warnx("cannot seek to %jd", (intmax_t)o.offset);
280 return -1;
281 }
282 memset(&bpb, 0, sizeof(bpb));
283 if (o.floppy) {
284 if (getstdfmt(o.floppy, &bpb) == -1)
285 return -1;
286 bpb.bsec = bpb.sec;
287 bpb.sec = 0;
288 bpb.bspf = bpb.spf;
289 bpb.spf = 0;
290 }
291 if (o.drive_heads)
292 bpb.hds = o.drive_heads;
293 if (o.sectors_per_track)
294 bpb.spt = o.sectors_per_track;
295 if (o.bytes_per_sector)
296 bpb.bps = o.bytes_per_sector;
297 if (o.size)
298 bpb.bsec = o.size;
299 if (o.hidden_sectors_set)
300 bpb.hid = o.hidden_sectors;
301 if (!(o.floppy || (o.drive_heads && o.sectors_per_track &&
302 o.bytes_per_sector && o.size && o.hidden_sectors_set))) {
303 if (getbpbinfo(fd, fname, dtype, o.hidden_sectors_set, &bpb,
304 o.create_size != 0) == -1)
305 return -1;
306 bpb.bsec -= (o.offset / bpb.bps);
307 if (bpb.spc == 0) { /* set defaults */
308 /* minimum cluster size */
309 switch (o.fat_type) {
310 case 12:
311 bpb.spc = 1; /* use 512 bytes */
312 x = 2; /* up to 2MB */
313 break;
314 case 16:
315 bpb.spc = 1; /* use 512 bytes */
316 x = 32; /* up to 32MB */
317 break;
318 default:
319 bpb.spc = 8; /* use 4k */
320 x = 8192; /* up to 8GB */
321 break;
322 }
323 x1 = howmany(bpb.bsec, (1048576 / 512)); /* -> MB */
324 while (bpb.spc < 128 && x < x1) {
325 x *= 2;
326 bpb.spc *= 2;
327 }
328 }
329 }
330
331 if (o.volume_label && !oklabel(o.volume_label)) {
332 warnx("%s: bad volume label", o.volume_label);
333 return -1;
334 }
335
336 switch (o.fat_type) {
337 case 0:
338 if (o.floppy)
339 o.fat_type = 12;
340 else if (!o.directory_entries && (o.info_sector || o.backup_sector))
341 o.fat_type = 32;
342 break;
343 case 12:
344 case 16:
345 if (o.info_sector) {
346 warnx("Cannot specify info sector with FAT%u", o.fat_type);
347 return -1;
348 }
349 if (o.backup_sector) {
350 warnx("Cannot specify backup sector with FAT%u", o.fat_type);
351 return -1;
352 }
353 break;
354 case 32:
355 if (o.directory_entries) {
356 warnx("Cannot specify directory entries with FAT32");
357 return -1;
358 }
359 break;
360 default:
361 warnx("%d: bad FAT type", o.fat_type);
362 return -1;
363 }
364 if (!powerof2(bpb.bps)) {
365 warnx("bytes/sector (%u) is not a power of 2", bpb.bps);
366 return -1;
367 }
368 if (bpb.bps < MINBPS) {
369 warnx("bytes/sector (%u) is too small; minimum is %u",
370 bpb.bps, MINBPS);
371 return -1;
372 }
373
374 if (o.floppy && o.fat_type == 32)
375 bpb.rde = 0;
376 if (o.block_size) {
377 if (!powerof2(o.block_size)) {
378 warnx("block size (%u) is not a power of 2", o.block_size);
379 return -1;
380 }
381 if (o.block_size < bpb.bps) {
382 warnx("block size (%u) is too small; minimum is %u",
383 o.block_size, bpb.bps);
384 return -1;
385 }
386 if (o.block_size > bpb.bps * MAXSPC) {
387 warnx("block size (%u) is too large; maximum is %u",
388 o.block_size, bpb.bps * MAXSPC);
389 return -1;
390 }
391 bpb.spc = o.block_size / bpb.bps;
392 }
393 if (o.sectors_per_cluster) {
394 if (!powerof2(o.sectors_per_cluster)) {
395 warnx("sectors/cluster (%u) is not a power of 2",
396 o.sectors_per_cluster);
397 return -1;
398 }
399 bpb.spc = o.sectors_per_cluster;
400 }
401 if (o.reserved_sectors)
402 bpb.res = o.reserved_sectors;
403 if (o.num_FAT) {
404 if (o.num_FAT > MAXNFT) {
405 warnx("number of FATs (%u) is too large; maximum is %u",
406 o.num_FAT, MAXNFT);
407 return -1;
408 }
409 bpb.nft = o.num_FAT;
410 }
411 if (o.directory_entries)
412 bpb.rde = o.directory_entries;
413 if (o.media_descriptor_set) {
414 if (o.media_descriptor < 0xf0) {
415 warnx("illegal media descriptor (%#x)", o.media_descriptor);
416 return -1;
417 }
418 bpb.mid = o.media_descriptor;
419 }
420 if (o.sectors_per_fat)
421 bpb.bspf = o.sectors_per_fat;
422 if (o.info_sector)
423 bpb.infs = o.info_sector;
424 if (o.backup_sector)
425 bpb.bkbs = o.backup_sector;
426 bss = 1;
427 bname = NULL;
428 fd1 = -1;
429 if (o.bootstrap) {
430 bname = o.bootstrap;
431 if (!strchr(bname, '/')) {
432 snprintf(buf, sizeof(buf), "/boot/%s", bname);
433 if (!(bname = strdup(buf))) {
434 warn(NULL);
435 return -1;
436 }
437 }
438 if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb)) {
439 warn("%s", bname);
440 return -1;
441 }
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 warnx("%s: inappropriate file type or format", bname);
445 return -1;
446 }
447 bss = sb.st_size / bpb.bps;
448 }
449 if (!bpb.nft)
450 bpb.nft = 2;
451 if (!o.fat_type) {
452 if (bpb.bsec < (bpb.res ? bpb.res : bss) +
453 howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
454 ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
455 bpb.nft +
456 howmany(bpb.rde ? bpb.rde : DEFRDE,
457 bpb.bps / sizeof(struct de)) +
458 (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
459 (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
460 o.fat_type = 12;
461 else if (bpb.rde || bpb.bsec <
462 (bpb.res ? bpb.res : bss) +
463 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
464 howmany(DEFRDE, bpb.bps / sizeof(struct de)) +
465 (MAXCLS16 + 1) *
466 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
467 o.fat_type = 16;
468 else
469 o.fat_type = 32;
470 }
471 x = bss;
472 if (o.fat_type == 32) {
473 if (!bpb.infs) {
474 if (x == MAXU16 || x == bpb.bkbs) {
475 warnx("no room for info sector");
476 return -1;
477 }
478 bpb.infs = x;
479 }
480 if (bpb.infs != MAXU16 && x <= bpb.infs)
481 x = bpb.infs + 1;
482 if (!bpb.bkbs) {
483 if (x == MAXU16) {
484 warnx("no room for backup sector");
485 return -1;
486 }
487 bpb.bkbs = x;
488 } else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs) {
489 warnx("backup sector would overwrite info sector");
490 return -1;
491 }
492 if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
493 x = bpb.bkbs + 1;
494 }
495 if (!bpb.res)
496 bpb.res = o.fat_type == 32 ? MAXIMUM(x, MAXIMUM(16384 / bpb.bps, 4)) : x;
497 else if (bpb.res < x) {
498 warnx("too few reserved sectors (need %d have %d)", x, bpb.res);
499 return -1;
500 }
501 if (o.fat_type != 32 && !bpb.rde)
502 bpb.rde = DEFRDE;
503 rds = howmany(bpb.rde, bpb.bps / sizeof(struct de));
504 if (!bpb.spc)
505 for (bpb.spc = howmany(o.fat_type == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
506 bpb.spc < MAXSPC &&
507 bpb.res +
508 howmany((RESFTE + maxcls(o.fat_type)) * (o.fat_type / BPN),
509 bpb.bps * NPB) * bpb.nft +
510 rds +
511 (u_int64_t)(maxcls(o.fat_type) + 1) * bpb.spc <= bpb.bsec;
512 bpb.spc <<= 1);
513 if (o.fat_type != 32 && bpb.bspf > MAXU16) {
514 warnx("too many sectors/FAT for FAT12/16");
515 return -1;
516 }
517 x1 = bpb.res + rds;
518 x = bpb.bspf ? bpb.bspf : 1;
519 if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec) {
520 warnx("meta data exceeds file system size");
521 return -1;
522 }
523 x1 += x * bpb.nft;
524 x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
525 (bpb.spc * bpb.bps * NPB + o.fat_type / BPN * bpb.nft);
526 x2 = howmany((RESFTE + MINIMUM(x, maxcls(o.fat_type))) * (o.fat_type / BPN),
527 bpb.bps * NPB);
528 if (!bpb.bspf) {
529 bpb.bspf = x2;
530 x1 += (bpb.bspf - 1) * bpb.nft;
531 }
532 cls = (bpb.bsec - x1) / bpb.spc;
533 x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (o.fat_type / BPN) - RESFTE;
534 if (cls > x)
535 cls = x;
536 if (bpb.bspf < x2) {
537 warnx("warning: sectors/FAT limits file system to %u clusters",
538 cls);
539 return -1;
540 }
541 if (cls < mincls(o.fat_type)) {
542 warnx("%u clusters too few clusters for FAT%u, need %u", cls,
543 o.fat_type, mincls(o.fat_type));
544 return -1;
545 }
546 if (cls > maxcls(o.fat_type)) {
547 cls = maxcls(o.fat_type);
548 bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
549 warnx("warning: FAT type limits file system to %u sectors",
550 bpb.bsec);
551 return -1;
552 }
553 printf("%s: %u sector%s in %u FAT%u cluster%s "
554 "(%u bytes/cluster)\n", fname, cls * bpb.spc,
555 cls * bpb.spc == 1 ? "" : "s", cls, o.fat_type,
556 cls == 1 ? "" : "s", bpb.bps * bpb.spc);
557 if (!bpb.mid)
558 bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
559 if (o.fat_type == 32)
560 bpb.rdcl = RESFTE;
561 if (bpb.hid + bpb.bsec <= MAXU16) {
562 bpb.sec = bpb.bsec;
563 bpb.bsec = 0;
564 }
565 if (o.fat_type != 32) {
566 bpb.spf = bpb.bspf;
567 bpb.bspf = 0;
568 }
569 ch = 0;
570 if (o.fat_type == 12)
571 ch = 1; /* 001 Primary DOS with 12 bit FAT */
572 else if (o.fat_type == 16) {
573 if (bpb.bsec == 0)
574 ch = 4; /* 004 Primary DOS with 16 bit FAT <32M */
575 else
576 ch = 6; /* 006 Primary 'big' DOS, 16-bit FAT (> 32MB) */
577 /*
578 * XXX: what about:
579 * 014 DOS (16-bit FAT) - LBA
580 * ?
581 */
582 } else if (o.fat_type == 32) {
583 ch = 11; /* 011 Primary DOS with 32 bit FAT */
584 /*
585 * XXX: what about:
586 * 012 Primary DOS with 32 bit FAT - LBA
587 * ?
588 */
589 }
590 if (ch != 0)
591 printf("MBR type: %d\n", ch);
592 print_bpb(&bpb);
593
594 gettimeofday(&tv, NULL);
595 now = tv.tv_sec;
596 tm = localtime(&now);
597 img = emalloc(bpb.bps);
598 dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;
599 signal(SIGINFO, infohandler);
600 for (lsn = 0; lsn < dir + (o.fat_type == 32 ? bpb.spc : rds); lsn++) {
601 if (got_siginfo) {
602 fprintf(stderr,"%s: writing sector %u of %u (%u%%)\n",
603 fname,lsn,(dir + (o.fat_type == 32 ? bpb.spc : rds)),
604 (lsn*100)/(dir + (o.fat_type == 32 ? bpb.spc : rds)));
605 got_siginfo = 0;
606 }
607 x = lsn;
608 if (o.bootstrap &&
609 o.fat_type == 32 && bpb.bkbs != MAXU16 &&
610 bss <= bpb.bkbs && x >= bpb.bkbs) {
611 x -= bpb.bkbs;
612 if (!x && lseek(fd1, o.offset, SEEK_SET)) {
613 warn("%s", bname);
614 return -1;
615 }
616 }
617 if (o.bootstrap && x < bss) {
618 if ((n = read(fd1, img, bpb.bps)) == -1) {
619 warn("%s", bname);
620 return -1;
621 }
622 if ((size_t)n != bpb.bps) {
623 warnx("%s: can't read sector %u", bname, x);
624 return -1;
625 }
626 } else
627 memset(img, 0, bpb.bps);
628 if (!lsn ||
629 (o.fat_type == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
630 x1 = sizeof(struct bs);
631 bsbpb = (struct bsbpb *)(img + x1);
632 mk2(bsbpb->bps, bpb.bps);
633 mk1(bsbpb->spc, bpb.spc);
634 mk2(bsbpb->res, bpb.res);
635 mk1(bsbpb->nft, bpb.nft);
636 mk2(bsbpb->rde, bpb.rde);
637 mk2(bsbpb->sec, bpb.sec);
638 mk1(bsbpb->mid, bpb.mid);
639 mk2(bsbpb->spf, bpb.spf);
640 mk2(bsbpb->spt, bpb.spt);
641 mk2(bsbpb->hds, bpb.hds);
642 mk4(bsbpb->hid, bpb.hid);
643 mk4(bsbpb->bsec, bpb.bsec);
644 x1 += sizeof(struct bsbpb);
645 if (o.fat_type == 32) {
646 bsxbpb = (struct bsxbpb *)(img + x1);
647 mk4(bsxbpb->bspf, bpb.bspf);
648 mk2(bsxbpb->xflg, 0);
649 mk2(bsxbpb->vers, 0);
650 mk4(bsxbpb->rdcl, bpb.rdcl);
651 mk2(bsxbpb->infs, bpb.infs);
652 mk2(bsxbpb->bkbs, bpb.bkbs);
653 x1 += sizeof(struct bsxbpb);
654 }
655 bsx = (struct bsx *)(img + x1);
656 mk1(bsx->sig, 0x29);
657 if (o.volume_id_set)
658 x = o.volume_id;
659 else
660 x = (((u_int)(1 + tm->tm_mon) << 8 |
661 (u_int)tm->tm_mday) +
662 ((u_int)tm->tm_sec << 8 |
663 (u_int)(tv.tv_usec / 10))) << 16 |
664 ((u_int)(1900 + tm->tm_year) +
665 ((u_int)tm->tm_hour << 8 |
666 (u_int)tm->tm_min));
667 mk4(bsx->volid, x);
668 mklabel(bsx->label, o.volume_label ? o.volume_label : "NO NAME");
669 snprintf(buf, sizeof(buf), "FAT%u", o.fat_type);
670 setstr(bsx->type, buf, sizeof(bsx->type));
671 if (!o.bootstrap) {
672 x1 += sizeof(struct bsx);
673 bs = (struct bs *)img;
674 mk1(bs->jmp[0], 0xeb);
675 mk1(bs->jmp[1], x1 - 2);
676 mk1(bs->jmp[2], 0x90);
677 setstr(bs->oem, o.OEM_string ? o.OEM_string : "NetBSD",
678 sizeof(bs->oem));
679 memcpy(img + x1, bootcode, sizeof(bootcode));
680 mk2(img + MINBPS - 2, DOSMAGIC);
681 }
682 } else if (o.fat_type == 32 && bpb.infs != MAXU16 &&
683 (lsn == bpb.infs ||
684 (bpb.bkbs != MAXU16 &&
685 lsn == bpb.bkbs + bpb.infs))) {
686 mk4(img, 0x41615252);
687 mk4(img + MINBPS - 28, 0x61417272);
688 mk4(img + MINBPS - 24, 0xffffffff);
689 mk4(img + MINBPS - 20, 0xffffffff);
690 mk2(img + MINBPS - 2, DOSMAGIC);
691 } else if (lsn >= bpb.res && lsn < dir &&
692 !((lsn - bpb.res) %
693 (bpb.spf ? bpb.spf : bpb.bspf))) {
694 mk1(img[0], bpb.mid);
695 for (x = 1; x < o.fat_type * (o.fat_type == 32 ? 3U : 2U) / 8U; x++)
696 mk1(img[x], o.fat_type == 32 && x % 4 == 3 ? 0x0f : 0xff);
697 } else if (lsn == dir && o.volume_label) {
698 de = (struct de *)img;
699 mklabel(de->namext, o.volume_label);
700 mk1(de->attr, 050);
701 x = (u_int)tm->tm_hour << 11 |
702 (u_int)tm->tm_min << 5 |
703 (u_int)tm->tm_sec >> 1;
704 mk2(de->time, x);
705 x = (u_int)(tm->tm_year - 80) << 9 |
706 (u_int)(tm->tm_mon + 1) << 5 |
707 (u_int)tm->tm_mday;
708 mk2(de->date, x);
709 }
710 if ((n = write(fd, img, bpb.bps)) == -1) {
711 warn("%s", fname);
712 return -1;
713 }
714 if ((size_t)n != bpb.bps) {
715 warnx("%s: can't write sector %u", fname, lsn);
716 return -1;
717 }
718 }
719 return 0;
720 }
721
722
723 /*
724 * Get a standard format.
725 */
726 static int
getstdfmt(const char * fmt,struct bpb * bpb)727 getstdfmt(const char *fmt, struct bpb *bpb)
728 {
729 u_int x, i;
730
731 x = sizeof(stdfmt) / sizeof(stdfmt[0]);
732 for (i = 0; i < x && strcmp(fmt, stdfmt[i].name); i++);
733 if (i == x) {
734 warnx("%s: unknown standard format", fmt);
735 return -1;
736 }
737 *bpb = stdfmt[i].bpb;
738 return 0;
739 }
740
741 /*
742 * Get disk slice, partition, and geometry information.
743 */
744 static int
getbpbinfo(int fd,const char * fname,const char * dtype,int iflag,struct bpb * bpb,int create)745 getbpbinfo(int fd, const char *fname, const char *dtype, int iflag,
746 struct bpb *bpb, int create)
747 {
748 const char *s1, *s2;
749 int part;
750
751 part = -1;
752 s1 = fname;
753 if ((s2 = strrchr(s1, '/')))
754 s1 = s2 + 1;
755 for (s2 = s1; *s2 && !isdigit((unsigned char)*s2); s2++);
756 if (!*s2 || s2 == s1)
757 s2 = NULL;
758 else
759 while (isdigit((unsigned char)*++s2));
760 s1 = s2;
761
762 if (((part != -1) && ((!iflag && part != -1) || !bpb->bsec)) ||
763 !bpb->bps || !bpb->spt || !bpb->hds) {
764 u_int sector_size;
765 u_int nsectors;
766 u_int ntracks;
767 u_int size;
768 {
769 struct stat st;
770
771 if (fstat(fd, &st) == -1) {
772 warnx("Can't get disk size for `%s'", fname);
773 return -1;
774 }
775 /* create a fake geometry for a file image */
776 sector_size = 512;
777 nsectors = 63;
778 ntracks = 255;
779 size = st.st_size / sector_size;
780 }
781 if (!bpb->bps) {
782 if (ckgeom(fname, sector_size, "bytes/sector") == -1)
783 return -1;
784 bpb->bps = sector_size;
785 }
786
787 if (nsectors > 63) {
788 /*
789 * The kernel doesn't accept BPB with spt > 63.
790 * (see sys/fs/msdosfs/msdosfs_vfsops.c:msdosfs_mountfs())
791 * If values taken from disklabel don't match these
792 * restrictions, use popular BIOS default values instead.
793 */
794 nsectors = 63;
795 }
796 if (!bpb->spt) {
797 if (ckgeom(fname, nsectors, "sectors/track") == -1)
798 return -1;
799 bpb->spt = nsectors;
800 }
801 if (!bpb->hds) {
802 if (ckgeom(fname, ntracks, "drive heads") == -1)
803 return -1;
804 bpb->hds = ntracks;
805 }
806 if (!bpb->bsec)
807 bpb->bsec = size;
808 }
809 return 0;
810 }
811
812 /*
813 * Print out BPB values.
814 */
815 static void
print_bpb(struct bpb * bpb)816 print_bpb(struct bpb *bpb)
817 {
818 printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
819 bpb->nft);
820 if (bpb->rde)
821 printf(" rde=%u", bpb->rde);
822 if (bpb->sec)
823 printf(" sec=%u", bpb->sec);
824 printf(" mid=%#x", bpb->mid);
825 if (bpb->spf)
826 printf(" spf=%u", bpb->spf);
827 printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
828 if (bpb->bsec)
829 printf(" bsec=%u", bpb->bsec);
830 if (!bpb->spf) {
831 printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
832 printf(" infs=");
833 printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
834 printf(" bkbs=");
835 printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
836 }
837 printf("\n");
838 }
839
840 /*
841 * Check a disk geometry value.
842 */
843 static int
ckgeom(const char * fname,u_int val,const char * msg)844 ckgeom(const char *fname, u_int val, const char *msg)
845 {
846 if (!val) {
847 warnx("%s: no default %s", fname, msg);
848 return -1;
849 }
850 if (val > MAXU16) {
851 warnx("%s: illegal %s", fname, msg);
852 return -1;
853 }
854 return 0;
855 }
856 /*
857 * Check a volume label.
858 */
859 static int
oklabel(const char * src)860 oklabel(const char *src)
861 {
862 int c, i;
863
864 for (i = 0; i <= 11; i++) {
865 c = (u_char)*src++;
866 if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
867 break;
868 }
869 return i && !c;
870 }
871
872 /*
873 * Make a volume label.
874 */
875 static void
mklabel(u_int8_t * dest,const char * src)876 mklabel(u_int8_t *dest, const char *src)
877 {
878 int c, i;
879
880 for (i = 0; i < 11; i++) {
881 c = *src ? toupper((unsigned char)*src++) : ' ';
882 *dest++ = !i && c == '\xe5' ? 5 : c;
883 }
884 }
885
886 /*
887 * Copy string, padding with spaces.
888 */
889 static void
setstr(u_int8_t * dest,const char * src,size_t len)890 setstr(u_int8_t *dest, const char *src, size_t len)
891 {
892 while (len--)
893 *dest++ = *src ? *src++ : ' ';
894 }
895
896 static void
infohandler(int sig)897 infohandler(int sig)
898 {
899 got_siginfo = 1;
900 }
901