xref: /plan9/sys/src/cmd/fossil/flfmt9660.c (revision 14cc0f535177405a84c5b73603a98e5db6674719)
1 /*
2  * Initialize a fossil file system from an ISO9660 image already in the
3  * file system.  This is a fairly bizarre thing to do, but it lets us generate
4  * installation CDs that double as valid Plan 9 disk partitions.
5  * People having trouble booting the CD can just copy it into a disk
6  * partition and you've got a working Plan 9 system.
7  *
8  * I've tried hard to keep all the associated cruft in this file.
9  * If you deleted this file and cut out the three calls into it from flfmt.c,
10  * no traces would remain.
11  */
12 
13 #include "stdinc.h"
14 #include "dat.h"
15 #include "fns.h"
16 #include "flfmt9660.h"
17 #include <bio.h>
18 #include <ctype.h>
19 
20 static Biobuf *b;
21 
22 enum{
23 	Tag = 0x96609660,
24 	Blocksize = 2048,
25 };
26 
27 #pragma varargck type "s" uchar*
28 #pragma varargck type "L" uchar*
29 #pragma varargck type "B" uchar*
30 #pragma varargck type "N" uchar*
31 #pragma varargck type "T" uchar*
32 #pragma varargck type "D" uchar*
33 
34 typedef struct Voldesc Voldesc;
35 struct Voldesc {
36 	uchar	magic[8];	/* 0x01, "CD001", 0x01, 0x00 */
37 	uchar	systemid[32];	/* system identifier */
38 	uchar	volumeid[32];	/* volume identifier */
39 	uchar	unused[8];	/* character set in secondary desc */
40 	uchar	volsize[8];	/* volume size */
41 	uchar	charset[32];
42 	uchar	volsetsize[4];	/* volume set size = 1 */
43 	uchar	volseqnum[4];	/* volume sequence number = 1 */
44 	uchar	blocksize[4];	/* logical block size */
45 	uchar	pathsize[8];	/* path table size */
46 	uchar	lpathloc[4];	/* Lpath */
47 	uchar	olpathloc[4];	/* optional Lpath */
48 	uchar	mpathloc[4];	/* Mpath */
49 	uchar	ompathloc[4];	/* optional Mpath */
50 	uchar	rootdir[34];	/* root directory */
51 	uchar	volsetid[128];	/* volume set identifier */
52 	uchar	publisher[128];
53 	uchar	prepid[128];	/* data preparer identifier */
54 	uchar	applid[128];	/* application identifier */
55 	uchar	notice[37];	/* copyright notice file */
56 	uchar	abstract[37];	/* abstract file */
57 	uchar	biblio[37];	/* bibliographic file */
58 	uchar	cdate[17];	/* creation date */
59 	uchar	mdate[17];	/* modification date */
60 	uchar	xdate[17];	/* expiration date */
61 	uchar	edate[17];	/* effective date */
62 	uchar	fsvers;		/* file system version = 1 */
63 };
64 
65 static void
dumpbootvol(void * a)66 dumpbootvol(void *a)
67 {
68 	Voldesc *v;
69 
70 	v = a;
71 	print("magic %.2ux %.5s %.2ux %2ux\n",
72 		v->magic[0], v->magic+1, v->magic[6], v->magic[7]);
73 	if(v->magic[0] == 0xFF)
74 		return;
75 
76 	print("system %.32T\n", v->systemid);
77 	print("volume %.32T\n", v->volumeid);
78 	print("volume size %.4N\n", v->volsize);
79 	print("charset %.2ux %.2ux %.2ux %.2ux %.2ux %.2ux %.2ux %.2ux\n",
80 		v->charset[0], v->charset[1], v->charset[2], v->charset[3],
81 		v->charset[4], v->charset[5], v->charset[6], v->charset[7]);
82 	print("volume set size %.2N\n", v->volsetsize);
83 	print("volume sequence number %.2N\n", v->volseqnum);
84 	print("logical block size %.2N\n", v->blocksize);
85 	print("path size %.4L\n", v->pathsize);
86 	print("lpath loc %.4L\n", v->lpathloc);
87 	print("opt lpath loc %.4L\n", v->olpathloc);
88 	print("mpath loc %.4B\n", v->mpathloc);
89 	print("opt mpath loc %.4B\n", v->ompathloc);
90 	print("rootdir %D\n", v->rootdir);
91 	print("volume set identifier %.128T\n", v->volsetid);
92 	print("publisher %.128T\n", v->publisher);
93 	print("preparer %.128T\n", v->prepid);
94 	print("application %.128T\n", v->applid);
95 	print("notice %.37T\n", v->notice);
96 	print("abstract %.37T\n", v->abstract);
97 	print("biblio %.37T\n", v->biblio);
98 	print("creation date %.17s\n", v->cdate);
99 	print("modification date %.17s\n", v->mdate);
100 	print("expiration date %.17s\n", v->xdate);
101 	print("effective date %.17s\n", v->edate);
102 	print("fs version %d\n", v->fsvers);
103 }
104 
105 typedef struct Cdir Cdir;
106 struct Cdir {
107 	uchar	len;
108 	uchar	xlen;
109 	uchar	dloc[8];
110 	uchar	dlen[8];
111 	uchar	date[7];
112 	uchar	flags;
113 	uchar	unitsize;
114 	uchar	gapsize;
115 	uchar	volseqnum[4];
116 	uchar	namelen;
117 	uchar	name[1];	/* chumminess */
118 };
119 #pragma varargck type "D" Cdir*
120 
121 static int
Dfmt(Fmt * fmt)122 Dfmt(Fmt *fmt)
123 {
124 	char buf[128];
125 	Cdir *c;
126 
127 	c = va_arg(fmt->args, Cdir*);
128 	if(c->namelen == 1 && c->name[0] == '\0' || c->name[0] == '\001') {
129 		snprint(buf, sizeof buf, ".%s dloc %.4N dlen %.4N",
130 			c->name[0] ? "." : "", c->dloc, c->dlen);
131 	} else {
132 		snprint(buf, sizeof buf, "%.*T dloc %.4N dlen %.4N", c->namelen, c->name,
133 			c->dloc, c->dlen);
134 	}
135 	fmtstrcpy(fmt, buf);
136 	return 0;
137 }
138 
139 char longc, shortc;
140 static void
bigend(void)141 bigend(void)
142 {
143 	longc = 'B';
144 }
145 
146 static void
littleend(void)147 littleend(void)
148 {
149 	longc = 'L';
150 }
151 
152 static ulong
big(void * a,int n)153 big(void *a, int n)
154 {
155 	uchar *p;
156 	ulong v;
157 	int i;
158 
159 	p = a;
160 	v = 0;
161 	for(i=0; i<n; i++)
162 		v = (v<<8) | *p++;
163 	return v;
164 }
165 
166 static ulong
little(void * a,int n)167 little(void *a, int n)
168 {
169 	uchar *p;
170 	ulong v;
171 	int i;
172 
173 	p = a;
174 	v = 0;
175 	for(i=0; i<n; i++)
176 		v |= (*p++<<(i*8));
177 	return v;
178 }
179 
180 /* numbers in big or little endian. */
181 static int
BLfmt(Fmt * fmt)182 BLfmt(Fmt *fmt)
183 {
184 	ulong v;
185 	uchar *p;
186 	char buf[20];
187 
188 	p = va_arg(fmt->args, uchar*);
189 
190 	if(!(fmt->flags&FmtPrec)) {
191 		fmtstrcpy(fmt, "*BL*");
192 		return 0;
193 	}
194 
195 	if(fmt->r == 'B')
196 		v = big(p, fmt->prec);
197 	else
198 		v = little(p, fmt->prec);
199 
200 	sprint(buf, "0x%.*lux", fmt->prec*2, v);
201 	fmt->flags &= ~FmtPrec;
202 	fmtstrcpy(fmt, buf);
203 	return 0;
204 }
205 
206 /* numbers in both little and big endian */
207 static int
Nfmt(Fmt * fmt)208 Nfmt(Fmt *fmt)
209 {
210 	char buf[100];
211 	uchar *p;
212 
213 	p = va_arg(fmt->args, uchar*);
214 
215 	sprint(buf, "%.*L %.*B", fmt->prec, p, fmt->prec, p+fmt->prec);
216 	fmt->flags &= ~FmtPrec;
217 	fmtstrcpy(fmt, buf);
218 	return 0;
219 }
220 
221 static int
asciiTfmt(Fmt * fmt)222 asciiTfmt(Fmt *fmt)
223 {
224 	char *p, buf[256];
225 	int i;
226 
227 	p = va_arg(fmt->args, char*);
228 	for(i=0; i<fmt->prec; i++)
229 		buf[i] = *p++;
230 	buf[i] = '\0';
231 	for(p=buf+strlen(buf); p>buf && p[-1]==' '; p--)
232 		;
233 	p[0] = '\0';
234 	fmt->flags &= ~FmtPrec;
235 	fmtstrcpy(fmt, buf);
236 	return 0;
237 }
238 
239 static void
ascii(void)240 ascii(void)
241 {
242 	fmtinstall('T', asciiTfmt);
243 }
244 
245 static int
runeTfmt(Fmt * fmt)246 runeTfmt(Fmt *fmt)
247 {
248 	Rune buf[256], *r;
249 	int i;
250 	uchar *p;
251 
252 	p = va_arg(fmt->args, uchar*);
253 	for(i=0; i*2+2<=fmt->prec; i++, p+=2)
254 		buf[i] = (p[0]<<8)|p[1];
255 	buf[i] = L'\0';
256 	for(r=buf+i; r>buf && r[-1]==L' '; r--)
257 		;
258 	r[0] = L'\0';
259 	fmt->flags &= ~FmtPrec;
260 	return fmtprint(fmt, "%S", buf);
261 }
262 
263 static void
getsect(uchar * buf,int n)264 getsect(uchar *buf, int n)
265 {
266 	if(Bseek(b, n*2048, 0) != n*2048 || Bread(b, buf, 2048) != 2048)
267 {
268 abort();
269 		sysfatal("reading block at %,d: %r", n*2048);
270 }
271 }
272 
273 static Header *h;
274 static int fd;
275 static char *file9660;
276 static int off9660;
277 static ulong startoff;
278 static ulong endoff;
279 static ulong fsoff;
280 static uchar root[2048];
281 static Voldesc *v;
282 static ulong iso9660start(Cdir*);
283 static void iso9660copydir(Fs*, File*, Cdir*);
284 static void iso9660copyfile(Fs*, File*, Cdir*);
285 
286 void
iso9660init(int xfd,Header * xh,char * xfile9660,int xoff9660)287 iso9660init(int xfd, Header *xh, char *xfile9660, int xoff9660)
288 {
289 	uchar sect[2048], sect2[2048];
290 
291 	fmtinstall('L', BLfmt);
292 	fmtinstall('B', BLfmt);
293 	fmtinstall('N', Nfmt);
294 	fmtinstall('D', Dfmt);
295 
296 	fd = xfd;
297 	h = xh;
298 	file9660 = xfile9660;
299 	off9660 = xoff9660;
300 
301 	if((b = Bopen(file9660, OREAD)) == nil)
302 		vtFatal("Bopen %s: %r", file9660);
303 
304 	getsect(root, 16);
305 	ascii();
306 
307 	v = (Voldesc*)root;
308 	if(memcmp(v->magic, "\x01CD001\x01\x00", 8) != 0)
309 		vtFatal("%s not a cd image", file9660);
310 
311 	startoff = iso9660start((Cdir*)v->rootdir)*Blocksize;
312 	endoff = little(v->volsize, 4);	/* already in bytes */
313 
314 	fsoff = off9660 + h->data*h->blockSize;
315 	if(fsoff > startoff)
316 		vtFatal("fossil data starts after cd data");
317 	if(off9660 + (vlong)h->end*h->blockSize < endoff)
318 		vtFatal("fossil data ends before cd data");
319 	if(fsoff%h->blockSize)
320 		vtFatal("cd offset not a multiple of fossil block size");
321 
322 	/* Read "same" block via CD image and via Fossil image */
323 	getsect(sect, startoff/Blocksize);
324 	if(seek(fd, startoff-off9660, 0) < 0)
325 		vtFatal("cannot seek to first data sector on cd via fossil");
326 fprint(2, "look for %lud at %lud\n", startoff, startoff-off9660);
327 	if(readn(fd, sect2, Blocksize) != Blocksize)
328 		vtFatal("cannot read first data sector on cd via fossil");
329 	if(memcmp(sect, sect2, Blocksize) != 0)
330 		vtFatal("iso9660 offset is a lie %08ux %08ux", *(long*)sect, *(long*)sect2);
331 }
332 
333 void
iso9660labels(Disk * disk,uchar * buf,void (* write)(int,u32int))334 iso9660labels(Disk *disk, uchar *buf, void (*write)(int, u32int))
335 {
336 	ulong sb, eb, bn, lb, llb;
337 	Label l;
338 	int lpb;
339 	uchar sect[Blocksize];
340 
341 	if(!diskReadRaw(disk, PartData, (startoff-fsoff)/h->blockSize, buf))
342 		vtFatal("disk read failed: %r");
343 	getsect(sect, startoff/Blocksize);
344 	if(memcmp(buf, sect, Blocksize) != 0)
345 		vtFatal("fsoff is wrong");
346 
347 	sb = (startoff-fsoff)/h->blockSize;
348 	eb = (endoff-fsoff+h->blockSize-1)/h->blockSize;
349 
350 	lpb = h->blockSize/LabelSize;
351 
352 	/* for each reserved block, mark label */
353 	llb = ~0;
354 	l.type = BtData;
355 	l.state = BsAlloc;
356 	l.tag = Tag;
357 	l.epoch = 1;
358 	l.epochClose = ~(u32int)0;
359 	for(bn=sb; bn<eb; bn++){
360 		lb = bn/lpb;
361 		if(lb != llb){
362 			if(llb != ~0)
363 				(*write)(PartLabel, llb);
364 			memset(buf, 0, h->blockSize);
365 		}
366 		llb = lb;
367 		labelPack(&l, buf, bn%lpb);
368 	}
369 	if(llb != ~0)
370 		(*write)(PartLabel, llb);
371 }
372 
373 void
iso9660copy(Fs * fs)374 iso9660copy(Fs *fs)
375 {
376 	File *root;
377 
378 	root = fileOpen(fs, "/active");
379 	iso9660copydir(fs, root, (Cdir*)v->rootdir);
380 	fileDecRef(root);
381 	vtRUnlock(fs->elk);
382 	if(!fsSnapshot(fs, nil, nil, 0))
383 		vtFatal("snapshot failed: %R");
384 	vtRLock(fs->elk);
385 }
386 
387 /*
388  * The first block used is the first data block of the leftmost file in the tree.
389  * (Just an artifact of how mk9660 works.)
390  */
391 static ulong
iso9660start(Cdir * c)392 iso9660start(Cdir *c)
393 {
394 	uchar sect[Blocksize];
395 
396 	while(c->flags&2){
397 		getsect(sect, little(c->dloc, 4));
398 		c = (Cdir*)sect;
399 		c = (Cdir*)((uchar*)c+c->len);	/* skip dot */
400 		c = (Cdir*)((uchar*)c+c->len);	/* skip dotdot */
401 		/* oops: might happen if leftmost directory is empty or leftmost file is zero length! */
402 		if(little(c->dloc, 4) == 0)
403 			vtFatal("error parsing cd image or unfortunate cd image");
404 	}
405 	return little(c->dloc, 4);
406 }
407 
408 static void
iso9660copydir(Fs * fs,File * dir,Cdir * cd)409 iso9660copydir(Fs *fs, File *dir, Cdir *cd)
410 {
411 	ulong off, end, len;
412 	uchar sect[Blocksize], *esect, *p;
413 	Cdir *c;
414 
415 	len = little(cd->dlen, 4);
416 	off = little(cd->dloc, 4)*Blocksize;
417 	end = off+len;
418 	esect = sect+Blocksize;
419 
420 	for(; off<end; off+=Blocksize){
421 		getsect(sect, off/Blocksize);
422 		p = sect;
423 		while(p < esect){
424 			c = (Cdir*)p;
425 			if(c->len <= 0)
426 				break;
427 			if(c->namelen!=1 || c->name[0]>1)
428 				iso9660copyfile(fs, dir, c);
429 			p += c->len;
430 		}
431 	}
432 }
433 
434 static char*
getname(uchar ** pp)435 getname(uchar **pp)
436 {
437 	uchar *p;
438 	int l;
439 
440 	p = *pp;
441 	l = *p;
442 	*pp = p+1+l;
443 	if(l == 0)
444 		return "";
445 	memmove(p, p+1, l);
446 	p[l] = 0;
447 	return (char*)p;
448 }
449 
450 static char*
getcname(Cdir * c)451 getcname(Cdir *c)
452 {
453 	uchar *up;
454 	char *p, *q;
455 
456 	up = &c->namelen;
457 	p = getname(&up);
458 	for(q=p; *q; q++)
459 		*q = tolower(*q);
460 	return p;
461 }
462 
463 static char
464 dmsize[12] =
465 {
466 	31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31,
467 };
468 
469 static ulong
getcdate(uchar * p)470 getcdate(uchar *p)	/* yMdhmsz */
471 {
472 	Tm tm;
473 	int y, M, d, h, m, s, tz;
474 
475 	y=p[0]; M=p[1]; d=p[2];
476 	h=p[3]; m=p[4]; s=p[5]; tz=p[6];
477 	USED(tz);
478 	if (y < 70)
479 		return 0;
480 	if (M < 1 || M > 12)
481 		return 0;
482 	if (d < 1 || d > dmsize[M-1])
483 		return 0;
484 	if (h > 23)
485 		return 0;
486 	if (m > 59)
487 		return 0;
488 	if (s > 59)
489 		return 0;
490 
491 	memset(&tm, 0, sizeof tm);
492 	tm.sec = s;
493 	tm.min = m;
494 	tm.hour = h;
495 	tm.mday = d;
496 	tm.mon = M-1;
497 	tm.year = 1900+y;
498 	tm.zone[0] = 0;
499 	return tm2sec(&tm);
500 }
501 
502 static int ind;
503 
504 static void
iso9660copyfile(Fs * fs,File * dir,Cdir * c)505 iso9660copyfile(Fs *fs, File *dir, Cdir *c)
506 {
507 	Dir d;
508 	DirEntry de;
509 	int sysl;
510 	uchar score[VtScoreSize];
511 	ulong off, foff, len, mode;
512 	uchar *p;
513 	File *f;
514 
515 	ind++;
516 	memset(&d, 0, sizeof d);
517 	p = c->name + c->namelen;
518 	if(((uintptr)p) & 1)
519 		p++;
520 	sysl = (uchar*)c + c->len - p;
521 	if(sysl <= 0)
522 		vtFatal("missing plan9 directory entry on %d/%d/%.*s", c->namelen, c->name[0], c->namelen, c->name);
523 	d.name = getname(&p);
524 	d.uid = getname(&p);
525 	d.gid = getname(&p);
526 	if((uintptr)p & 1)
527 		p++;
528 	d.mode = little(p, 4);
529 	if(d.name[0] == 0)
530 		d.name = getcname(c);
531 	d.mtime = getcdate(c->date);
532 	d.atime = d.mtime;
533 
534 if(d.mode&DMDIR)	print("%*scopy %s %s %s %luo\n", ind*2, "", d.name, d.uid, d.gid, d.mode);
535 
536 	mode = d.mode&0777;
537 	if(d.mode&DMDIR)
538 		mode |= ModeDir;
539 	if((f = fileCreate(dir, d.name, mode, d.uid)) == nil)
540 		vtFatal("could not create file '%s': %r", d.name);
541 	if(d.mode&DMDIR)
542 		iso9660copydir(fs, f, c);
543 	else{
544 		len = little(c->dlen, 4);
545 		off = little(c->dloc, 4)*Blocksize;
546 		for(foff=0; foff<len; foff+=h->blockSize){
547 			localToGlobal((off+foff-fsoff)/h->blockSize, score);
548 			if(!fileMapBlock(f, foff/h->blockSize, score, Tag))
549 				vtFatal("fileMapBlock: %R");
550 		}
551 		if(!fileSetSize(f, len))
552 			vtFatal("fileSetSize: %R");
553 	}
554 	if(!fileGetDir(f, &de))
555 		vtFatal("fileGetDir: %R");
556 	de.uid = d.uid;
557 	de.gid = d.gid;
558 	de.mtime = d.mtime;
559 	de.atime = d.atime;
560 	de.mode = d.mode&0777;
561 	if(!fileSetDir(f, &de, "sys"))
562 		vtFatal("fileSetDir: %R");
563 	fileDecRef(f);
564 	ind--;
565 }
566