xref: /freebsd/sys/fs/cd9660/cd9660_vfsops.c (revision 4543ef516683042d46f3bd3bb8a4f3f746e00499)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley
8  * by Pace Willisson (pace@blitz.com).  The Rock Ridge Extension
9  * Support code is derived from software contributed to Berkeley
10  * by Atsushi Murai (amurai@spec.co.jp).
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/namei.h>
40 #include <sys/priv.h>
41 #include <sys/proc.h>
42 #include <sys/kernel.h>
43 #include <sys/vnode.h>
44 #include <sys/mount.h>
45 #include <sys/bio.h>
46 #include <sys/buf.h>
47 #include <sys/cdio.h>
48 #include <sys/conf.h>
49 #include <sys/fcntl.h>
50 #include <sys/malloc.h>
51 #include <sys/stat.h>
52 #include <sys/syslog.h>
53 #include <sys/iconv.h>
54 
55 #include <fs/cd9660/iso.h>
56 #include <fs/cd9660/iso_rrip.h>
57 #include <fs/cd9660/cd9660_node.h>
58 #include <fs/cd9660/cd9660_mount.h>
59 
60 #include <geom/geom.h>
61 #include <geom/geom_vfs.h>
62 
63 MALLOC_DEFINE(M_ISOFSMNT, "isofs_mount", "ISOFS mount structure");
64 MALLOC_DEFINE(M_ISOFSNODE, "isofs_node", "ISOFS vnode private part");
65 
66 struct iconv_functions *cd9660_iconv = NULL;
67 
68 static vfs_mount_t	cd9660_mount;
69 static vfs_cmount_t	cd9660_cmount;
70 static vfs_unmount_t	cd9660_unmount;
71 static vfs_root_t	cd9660_root;
72 static vfs_statfs_t	cd9660_statfs;
73 static vfs_vget_t	cd9660_vget;
74 static vfs_fhtovp_t	cd9660_fhtovp;
75 
76 static struct vfsops cd9660_vfsops = {
77 	.vfs_fhtovp =		cd9660_fhtovp,
78 	.vfs_mount =		cd9660_mount,
79 	.vfs_cmount =		cd9660_cmount,
80 	.vfs_root =		cd9660_root,
81 	.vfs_statfs =		cd9660_statfs,
82 	.vfs_unmount =		cd9660_unmount,
83 	.vfs_vget =		cd9660_vget,
84 };
85 VFS_SET(cd9660_vfsops, cd9660, VFCF_READONLY);
86 MODULE_VERSION(cd9660, 1);
87 
88 static int cd9660_vfs_hash_cmp(struct vnode *vp, void *pino);
89 static int iso_mountfs(struct vnode *devvp, struct mount *mp);
90 
91 /*
92  * VFS Operations.
93  */
94 
95 static int
96 cd9660_cmount(struct mntarg *ma, void *data, uint64_t flags)
97 {
98 	struct iso_args args;
99 	int error;
100 
101 	error = copyin(data, &args, sizeof args);
102 	if (error)
103 		return (error);
104 
105 	ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN);
106 	ma = mount_arg(ma, "export", &args.export, sizeof(args.export));
107 	if (args.flags & ISOFSMNT_UID)
108 		ma = mount_argf(ma, "uid", "%d", args.uid);
109 	if (args.flags & ISOFSMNT_GID)
110 		ma = mount_argf(ma, "gid", "%d", args.gid);
111 	ma = mount_argf(ma, "mask", "%d", args.fmask);
112 	ma = mount_argf(ma, "dirmask", "%d", args.dmask);
113 	ma = mount_argsu(ma, "cs_disk", args.cs_disk, 64);
114 	ma = mount_argsu(ma, "cs_local", args.cs_local, 64);
115 	ma = mount_argf(ma, "ssector", "%u", args.ssector);
116 	ma = mount_argb(ma, !(args.flags & ISOFSMNT_NORRIP), "norrip");
117 	ma = mount_argb(ma, args.flags & ISOFSMNT_GENS, "nogens");
118 	ma = mount_argb(ma, args.flags & ISOFSMNT_EXTATT, "noextatt");
119 	ma = mount_argb(ma, !(args.flags & ISOFSMNT_NOJOLIET), "nojoliet");
120 	ma = mount_argb(ma,
121 	    args.flags & ISOFSMNT_BROKENJOLIET, "nobrokenjoliet");
122 	ma = mount_argb(ma, args.flags & ISOFSMNT_KICONV, "nokiconv");
123 
124 	error = kernel_mount(ma, flags);
125 
126 	return (error);
127 }
128 
129 static int
130 cd9660_mount(struct mount *mp)
131 {
132 	struct vnode *devvp;
133 	struct thread *td;
134 	char *fspec;
135 	int error;
136 	accmode_t accmode;
137 	struct nameidata ndp;
138 	struct iso_mnt *imp = NULL;
139 
140 	td = curthread;
141 
142 	/*
143 	 * Unconditionally mount as read-only.
144 	 */
145 	MNT_ILOCK(mp);
146 	mp->mnt_flag |= MNT_RDONLY;
147 	MNT_IUNLOCK(mp);
148 
149 	fspec = vfs_getopts(mp->mnt_optnew, "from", &error);
150 	if (error)
151 		return (error);
152 
153 	imp = VFSTOISOFS(mp);
154 
155 	if (mp->mnt_flag & MNT_UPDATE) {
156 		if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0))
157 			return (0);
158 	}
159 	/*
160 	 * Not an update, or updating the name: look up the name
161 	 * and verify that it refers to a sensible block device.
162 	 */
163 	NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec);
164 	if ((error = namei(&ndp)))
165 		return (error);
166 	NDFREE_PNBUF(&ndp);
167 	devvp = ndp.ni_vp;
168 
169 	if (!vn_isdisk_error(devvp, &error)) {
170 		vput(devvp);
171 		return (error);
172 	}
173 
174 	/*
175 	 * Verify that user has necessary permissions on the device,
176 	 * or has superuser abilities
177 	 */
178 	accmode = VREAD;
179 	error = VOP_ACCESS(devvp, accmode, td->td_ucred, td);
180 	if (error)
181 		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
182 	if (error) {
183 		vput(devvp);
184 		return (error);
185 	}
186 
187 	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
188 		error = iso_mountfs(devvp, mp);
189 		if (error)
190 			vrele(devvp);
191 	} else {
192 		if (devvp != imp->im_devvp)
193 			error = EINVAL;	/* needs translation */
194 		vput(devvp);
195 	}
196 	if (error)
197 		return (error);
198 	vfs_mountedfrom(mp, fspec);
199 	return (0);
200 }
201 
202 /*
203  * Common code for mount and mountroot
204  */
205 static int
206 iso_mountfs(struct vnode *devvp, struct mount *mp)
207 {
208 	struct iso_mnt *isomp = NULL;
209 	struct buf *bp = NULL;
210 	struct buf *pribp = NULL, *supbp = NULL;
211 	struct cdev *dev;
212 	int error = EINVAL;
213 	int high_sierra = 0;
214 	int iso_bsize;
215 	int iso_blknum;
216 	int joliet_level;
217 	int isverified = 0;
218 	struct iso_volume_descriptor *vdp = NULL;
219 	struct iso_primary_descriptor *pri = NULL;
220 	struct iso_sierra_primary_descriptor *pri_sierra = NULL;
221 	struct iso_supplementary_descriptor *sup = NULL;
222 	struct iso_directory_record *rootp;
223 	int logical_block_size, ssector;
224 	struct g_consumer *cp;
225 	struct bufobj *bo;
226 	char *cs_local, *cs_disk;
227 	int v;
228 
229 	dev = devvp->v_rdev;
230 	dev_ref(dev);
231 	g_topology_lock();
232 	error = g_vfs_open(devvp, &cp, "cd9660", 0);
233 	if (error == 0)
234 		g_getattr("MNT::verified", cp, &isverified);
235 	g_topology_unlock();
236 	VOP_UNLOCK(devvp);
237 	if (error)
238 		goto out;
239 	if (devvp->v_rdev->si_iosize_max != 0)
240 		mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
241 	if (mp->mnt_iosize_max > maxphys)
242 		mp->mnt_iosize_max = maxphys;
243 
244 	bo = &devvp->v_bufobj;
245 
246 	/* This is the "logical sector size".  The standard says this
247 	 * should be 2048 or the physical sector size on the device,
248 	 * whichever is greater.
249 	 */
250 	if ((ISO_DEFAULT_BLOCK_SIZE % cp->provider->sectorsize) != 0) {
251 		error = EINVAL;
252 		goto out;
253 	}
254 
255 	iso_bsize = cp->provider->sectorsize;
256 
257 	joliet_level = 0;
258 	if (1 != vfs_scanopt(mp->mnt_optnew, "ssector", "%d", &ssector))
259 		ssector = 0;
260 	for (iso_blknum = 16 + ssector;
261 	     iso_blknum < 100 + ssector;
262 	     iso_blknum++) {
263 		if ((error = bread(devvp, iso_blknum * btodb(ISO_DEFAULT_BLOCK_SIZE),
264 				  iso_bsize, NOCRED, &bp)) != 0)
265 			goto out;
266 
267 		vdp = (struct iso_volume_descriptor *)bp->b_data;
268 		if (bcmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) != 0) {
269 			if (bcmp (vdp->id_sierra, ISO_SIERRA_ID,
270 				  sizeof vdp->id_sierra) != 0) {
271 				error = EINVAL;
272 				goto out;
273 			} else
274 				high_sierra = 1;
275 		}
276 		switch (isonum_711 (high_sierra? vdp->type_sierra: vdp->type)){
277 		case ISO_VD_PRIMARY:
278 			if (pribp == NULL) {
279 				pribp = bp;
280 				bp = NULL;
281 				pri = (struct iso_primary_descriptor *)vdp;
282 				pri_sierra =
283 				  (struct iso_sierra_primary_descriptor *)vdp;
284 			}
285 			break;
286 
287 		case ISO_VD_SUPPLEMENTARY:
288 			if (supbp == NULL) {
289 				supbp = bp;
290 				bp = NULL;
291 				sup = (struct iso_supplementary_descriptor *)vdp;
292 
293 				if (!vfs_flagopt(mp->mnt_optnew, "nojoliet", NULL, 0)) {
294 					if (bcmp(sup->escape, "%/@", 3) == 0)
295 						joliet_level = 1;
296 					if (bcmp(sup->escape, "%/C", 3) == 0)
297 						joliet_level = 2;
298 					if (bcmp(sup->escape, "%/E", 3) == 0)
299 						joliet_level = 3;
300 
301 					if ((isonum_711 (sup->flags) & 1) &&
302 					    !vfs_flagopt(mp->mnt_optnew, "brokenjoliet", NULL, 0))
303 						joliet_level = 0;
304 				}
305 			}
306 			break;
307 
308 		case ISO_VD_END:
309 			goto vd_end;
310 
311 		default:
312 			break;
313 		}
314 		if (bp != NULL) {
315 			brelse(bp);
316 			bp = NULL;
317 		}
318 	}
319  vd_end:
320 	if (bp != NULL) {
321 		brelse(bp);
322 		bp = NULL;
323 	}
324 
325 	if (pri == NULL) {
326 		error = EINVAL;
327 		goto out;
328 	}
329 
330 	logical_block_size =
331 		isonum_723 (high_sierra?
332 			    pri_sierra->logical_block_size:
333 			    pri->logical_block_size);
334 
335 	if (logical_block_size < DEV_BSIZE || logical_block_size > MAXBSIZE
336 	    || (logical_block_size & (logical_block_size - 1)) != 0) {
337 		error = EINVAL;
338 		goto out;
339 	}
340 
341 	if (logical_block_size < cp->provider->sectorsize) {
342 		printf("cd9660: Unsupported logical block size %u\n",
343 		    logical_block_size);
344 		error = EINVAL;
345 		goto out;
346 	}
347 
348 	rootp = (struct iso_directory_record *)
349 		(high_sierra?
350 		 pri_sierra->root_directory_record:
351 		 pri->root_directory_record);
352 
353 	isomp = malloc(sizeof *isomp, M_ISOFSMNT, M_WAITOK | M_ZERO);
354 	isomp->im_cp = cp;
355 	isomp->im_bo = bo;
356 	isomp->logical_block_size = logical_block_size;
357 	isomp->volume_space_size =
358 		isonum_733 (high_sierra?
359 			    pri_sierra->volume_space_size:
360 			    pri->volume_space_size);
361 	isomp->joliet_level = 0;
362 	/*
363 	 * Since an ISO9660 multi-session CD can also access previous
364 	 * sessions, we have to include them into the space consider-
365 	 * ations.  This doesn't yield a very accurate number since
366 	 * parts of the old sessions might be inaccessible now, but we
367 	 * can't do much better.  This is also important for the NFS
368 	 * filehandle validation.
369 	 */
370 	isomp->volume_space_size += ssector;
371 	memcpy(isomp->root, rootp, sizeof isomp->root);
372 	isomp->root_extent = isonum_733 (rootp->extent);
373 	isomp->root_size = isonum_733 (rootp->size);
374 
375 	isomp->im_bmask = logical_block_size - 1;
376 	isomp->im_bshift = ffs(logical_block_size) - 1;
377 
378 	pribp->b_flags |= B_AGE;
379 	brelse(pribp);
380 	pribp = NULL;
381 	rootp = NULL;
382 	pri = NULL;
383 	pri_sierra = NULL;
384 
385 	mp->mnt_data = isomp;
386 	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
387 	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
388 	MNT_ILOCK(mp);
389 	if (isverified)
390 		mp->mnt_flag |= MNT_VERIFIED;
391 	mp->mnt_flag |= MNT_LOCAL;
392 	mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED;
393 	MNT_IUNLOCK(mp);
394 	isomp->im_mountp = mp;
395 	isomp->im_dev = dev;
396 	isomp->im_devvp = devvp;
397 	isomp->im_fmask = isomp->im_dmask = ACCESSPERMS;
398 
399 	vfs_flagopt(mp->mnt_optnew, "norrip", &isomp->im_flags, ISOFSMNT_NORRIP);
400 	vfs_flagopt(mp->mnt_optnew, "gens", &isomp->im_flags, ISOFSMNT_GENS);
401 	vfs_flagopt(mp->mnt_optnew, "extatt", &isomp->im_flags, ISOFSMNT_EXTATT);
402 	vfs_flagopt(mp->mnt_optnew, "nojoliet", &isomp->im_flags, ISOFSMNT_NOJOLIET);
403 	vfs_flagopt(mp->mnt_optnew, "kiconv", &isomp->im_flags, ISOFSMNT_KICONV);
404 
405 	if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1) {
406 		isomp->im_flags |= ISOFSMNT_UID;
407 		isomp->im_uid = v;
408 	}
409 	if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1) {
410 		isomp->im_flags |= ISOFSMNT_GID;
411 		isomp->im_gid = v;
412 	}
413 	if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1) {
414 		isomp->im_fmask &= v;
415 	}
416 	if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1) {
417 		isomp->im_dmask &= v;
418 	}
419 
420 	/* Check the Rock Ridge Extension support */
421 	if (!(isomp->im_flags & ISOFSMNT_NORRIP)) {
422 		if ((error = bread(isomp->im_devvp, (isomp->root_extent +
423 		    isonum_711(((struct iso_directory_record *)isomp->root)->
424 		    ext_attr_length)) << (isomp->im_bshift - DEV_BSHIFT),
425 		    isomp->logical_block_size, NOCRED, &bp)) != 0)
426 			goto out;
427 
428 		rootp = (struct iso_directory_record *)bp->b_data;
429 
430 		if ((isomp->rr_skip = cd9660_rrip_offset(rootp,isomp)) < 0) {
431 		    isomp->im_flags |= ISOFSMNT_NORRIP;
432 		} else {
433 		    isomp->im_flags &= ~ISOFSMNT_GENS;
434 		}
435 
436 		/*
437 		 * The contents are valid,
438 		 * but they will get reread as part of another vnode, so...
439 		 */
440 		bp->b_flags |= B_AGE;
441 		brelse(bp);
442 		bp = NULL;
443 		rootp = NULL;
444 	}
445 
446 	if (isomp->im_flags & ISOFSMNT_KICONV && cd9660_iconv) {
447 		cs_local = vfs_getopts(mp->mnt_optnew, "cs_local", &error);
448 		if (error)
449 			goto out;
450 		cs_disk = vfs_getopts(mp->mnt_optnew, "cs_disk", &error);
451 		if (error)
452 			goto out;
453 		cd9660_iconv->open(cs_local, cs_disk, &isomp->im_d2l);
454 		cd9660_iconv->open(cs_disk, cs_local, &isomp->im_l2d);
455 	} else {
456 		isomp->im_d2l = NULL;
457 		isomp->im_l2d = NULL;
458 	}
459 
460 	if (high_sierra) {
461 		/* this effectively ignores all the mount flags */
462 		if (bootverbose)
463 			log(LOG_INFO, "cd9660: High Sierra Format\n");
464 		isomp->iso_ftype = ISO_FTYPE_HIGH_SIERRA;
465 	} else
466 		switch (isomp->im_flags&(ISOFSMNT_NORRIP|ISOFSMNT_GENS)) {
467 		  default:
468 			  isomp->iso_ftype = ISO_FTYPE_DEFAULT;
469 			  break;
470 		  case ISOFSMNT_GENS|ISOFSMNT_NORRIP:
471 			  isomp->iso_ftype = ISO_FTYPE_9660;
472 			  break;
473 		  case 0:
474 			  if (bootverbose)
475 			  	  log(LOG_INFO, "cd9660: RockRidge Extension\n");
476 			  isomp->iso_ftype = ISO_FTYPE_RRIP;
477 			  break;
478 		}
479 
480 	/* Decide whether to use the Joliet descriptor */
481 
482 	if (isomp->iso_ftype != ISO_FTYPE_RRIP && joliet_level) {
483 		if (bootverbose)
484 			log(LOG_INFO, "cd9660: Joliet Extension (Level %d)\n",
485 			    joliet_level);
486 		rootp = (struct iso_directory_record *)
487 			sup->root_directory_record;
488 		memcpy(isomp->root, rootp, sizeof isomp->root);
489 		isomp->root_extent = isonum_733 (rootp->extent);
490 		isomp->root_size = isonum_733 (rootp->size);
491 		isomp->joliet_level = joliet_level;
492 		supbp->b_flags |= B_AGE;
493 	}
494 
495 	if (supbp) {
496 		brelse(supbp);
497 		supbp = NULL;
498 		sup = NULL;
499 	}
500 
501 	return 0;
502 out:
503 	if (bp != NULL)
504 		brelse(bp);
505 	if (pribp != NULL)
506 		brelse(pribp);
507 	if (supbp != NULL)
508 		brelse(supbp);
509 	if (cp != NULL) {
510 		g_topology_lock();
511 		g_vfs_close(cp);
512 		g_topology_unlock();
513 	}
514 	if (isomp) {
515 		free(isomp, M_ISOFSMNT);
516 		mp->mnt_data = NULL;
517 	}
518 	dev_rel(dev);
519 	return error;
520 }
521 
522 /*
523  * unmount system call
524  */
525 static int
526 cd9660_unmount(struct mount *mp, int mntflags)
527 {
528 	struct iso_mnt *isomp;
529 	int error, flags = 0;
530 
531 	if (mntflags & MNT_FORCE)
532 		flags |= FORCECLOSE;
533 	if ((error = vflush(mp, 0, flags, curthread)))
534 		return (error);
535 
536 	isomp = VFSTOISOFS(mp);
537 
538 	if (isomp->im_flags & ISOFSMNT_KICONV && cd9660_iconv) {
539 		if (isomp->im_d2l)
540 			cd9660_iconv->close(isomp->im_d2l);
541 		if (isomp->im_l2d)
542 			cd9660_iconv->close(isomp->im_l2d);
543 	}
544 	g_topology_lock();
545 	g_vfs_close(isomp->im_cp);
546 	g_topology_unlock();
547 	vrele(isomp->im_devvp);
548 	dev_rel(isomp->im_dev);
549 	free(isomp, M_ISOFSMNT);
550 	mp->mnt_data = NULL;
551 	return (error);
552 }
553 
554 /*
555  * Return root of a filesystem
556  */
557 static int
558 cd9660_root(struct mount *mp, int flags, struct vnode **vpp)
559 {
560 	struct iso_mnt *imp = VFSTOISOFS(mp);
561 	struct iso_directory_record *dp =
562 	    (struct iso_directory_record *)imp->root;
563 	cd_ino_t ino = isodirino(dp, imp);
564 
565 	/*
566 	 * With RRIP we must use the `.' entry of the root directory.
567 	 * Simply tell vget, that it's a relocated directory.
568 	 */
569 	return (cd9660_vget_internal(mp, ino, flags, vpp,
570 	    imp->iso_ftype == ISO_FTYPE_RRIP, dp));
571 }
572 
573 /*
574  * Get filesystem statistics.
575  */
576 static int
577 cd9660_statfs(struct mount *mp, struct statfs *sbp)
578 {
579 	struct iso_mnt *isomp;
580 
581 	isomp = VFSTOISOFS(mp);
582 
583 	sbp->f_bsize = isomp->logical_block_size;
584 	sbp->f_iosize = sbp->f_bsize;	/* XXX */
585 	sbp->f_blocks = isomp->volume_space_size;
586 	sbp->f_bfree = 0; /* total free blocks */
587 	sbp->f_bavail = 0; /* blocks free for non superuser */
588 	sbp->f_files =	0; /* total files */
589 	sbp->f_ffree = 0; /* free file nodes */
590 	return 0;
591 }
592 
593 /*
594  * File handle to vnode
595  *
596  * Have to be really careful about stale file handles:
597  * - check that the inode number is in range
598  * - call iget() to get the locked inode
599  * - check for an unallocated inode (i_mode == 0)
600  * - check that the generation number matches
601  */
602 
603 /* ARGSUSED */
604 static int
605 cd9660_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
606 {
607 	struct ifid ifh;
608 	struct iso_node *ip;
609 	struct vnode *nvp;
610 	int error;
611 
612 	memcpy(&ifh, fhp, sizeof(ifh));
613 
614 #ifdef	ISOFS_DBG
615 	printf("fhtovp: ino %d, start %ld\n",
616 	    ifh.ifid_ino, ifh.ifid_start);
617 #endif
618 
619 	if ((error = VFS_VGET(mp, ifh.ifid_ino, LK_EXCLUSIVE, &nvp)) != 0) {
620 		*vpp = NULLVP;
621 		return (error);
622 	}
623 	ip = VTOI(nvp);
624 	if (ip->inode.iso_mode == 0) {
625 		vput(nvp);
626 		*vpp = NULLVP;
627 		return (ESTALE);
628 	}
629 	*vpp = nvp;
630 	vnode_create_vobject(*vpp, ip->i_size, curthread);
631 	return (0);
632 }
633 
634 /*
635  * Conform to standard VFS interface; can't vget arbitrary inodes beyond 4GB
636  * into media with current inode scheme and 32-bit ino_t.  This shouldn't be
637  * needed for anything other than nfsd, and who exports a mounted DVD over NFS?
638  */
639 static int
640 cd9660_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
641 {
642 
643 	/*
644 	 * XXXX
645 	 * It would be nice if we didn't always set the `relocated' flag
646 	 * and force the extra read, but I don't want to think about fixing
647 	 * that right now.
648 	 */
649 	return (cd9660_vget_internal(mp, ino, flags, vpp,
650 #if 0
651 	    VFSTOISOFS(mp)->iso_ftype == ISO_FTYPE_RRIP,
652 #else
653 	    0,
654 #endif
655 	    (struct iso_directory_record *)0));
656 }
657 
658 /* Use special comparator for full 64-bit ino comparison. */
659 static int
660 cd9660_vfs_hash_cmp(struct vnode *vp, void *pino)
661 {
662 	struct iso_node *ip;
663 	cd_ino_t ino;
664 
665 	ip = VTOI(vp);
666 	ino = *(cd_ino_t *)pino;
667 	return (ip->i_number != ino);
668 }
669 
670 int
671 cd9660_vget_internal(struct mount *mp, cd_ino_t ino, int flags,
672     struct vnode **vpp, int relocated, struct iso_directory_record *isodir)
673 {
674 	struct iso_mnt *imp;
675 	struct iso_node *ip;
676 	struct buf *bp;
677 	struct vnode *vp;
678 	int error;
679 	struct thread *td;
680 
681 	td = curthread;
682 	error = vfs_hash_get(mp, ino, flags, td, vpp, cd9660_vfs_hash_cmp,
683 	    &ino);
684 	if (error || *vpp != NULL)
685 		return (error);
686 
687 	/*
688 	 * We must promote to an exclusive lock for vnode creation.  This
689 	 * can happen if lookup is passed LOCKSHARED.
690  	 */
691 	if ((flags & LK_TYPE_MASK) == LK_SHARED) {
692 		flags &= ~LK_TYPE_MASK;
693 		flags |= LK_EXCLUSIVE;
694 	}
695 
696 	/*
697 	 * We do not lock vnode creation as it is believed to be too
698 	 * expensive for such rare case as simultaneous creation of vnode
699 	 * for same ino by different processes. We just allow them to race
700 	 * and check later to decide who wins. Let the race begin!
701 	 */
702 
703 	imp = VFSTOISOFS(mp);
704 
705 	/* Allocate a new vnode/iso_node. */
706 	if ((error = getnewvnode("isofs", mp, &cd9660_vnodeops, &vp)) != 0) {
707 		*vpp = NULLVP;
708 		return (error);
709 	}
710 	ip = malloc(sizeof(struct iso_node), M_ISOFSNODE,
711 	    M_WAITOK | M_ZERO);
712 	vp->v_data = ip;
713 	ip->i_vnode = vp;
714 	ip->i_number = ino;
715 
716 	lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
717 	error = insmntque(vp, mp);
718 	if (error != 0) {
719 		free(ip, M_ISOFSNODE);
720 		*vpp = NULLVP;
721 		return (error);
722 	}
723 	error = vfs_hash_insert(vp, ino, flags, td, vpp, cd9660_vfs_hash_cmp,
724 	    &ino);
725 	if (error || *vpp != NULL)
726 		return (error);
727 
728 	if (isodir == NULL) {
729 		int lbn, off;
730 
731 		lbn = lblkno(imp, ino);
732 		if (lbn >= imp->volume_space_size) {
733 			vput(vp);
734 			printf("fhtovp: lbn exceed volume space %d\n", lbn);
735 			return (ESTALE);
736 		}
737 
738 		off = blkoff(imp, ino);
739 		if (off + ISO_DIRECTORY_RECORD_SIZE > imp->logical_block_size) {
740 			vput(vp);
741 			printf("fhtovp: crosses block boundary %d\n",
742 			       off + ISO_DIRECTORY_RECORD_SIZE);
743 			return (ESTALE);
744 		}
745 
746 		error = bread(imp->im_devvp,
747 			      lbn << (imp->im_bshift - DEV_BSHIFT),
748 			      imp->logical_block_size, NOCRED, &bp);
749 		if (error) {
750 			vput(vp);
751 			printf("fhtovp: bread error %d\n",error);
752 			return (error);
753 		}
754 		isodir = (struct iso_directory_record *)(bp->b_data + off);
755 
756 		if (off + isonum_711(isodir->length) >
757 		    imp->logical_block_size) {
758 			vput(vp);
759 			brelse(bp);
760 			printf("fhtovp: directory crosses block boundary %d[off=%d/len=%d]\n",
761 			       off +isonum_711(isodir->length), off,
762 			       isonum_711(isodir->length));
763 			return (ESTALE);
764 		}
765 
766 #if 0
767 		if (isonum_733(isodir->extent) +
768 		    isonum_711(isodir->ext_attr_length) != ifhp->ifid_start) {
769 			brelse(bp);
770 			printf("fhtovp: file start miss %d vs %d\n",
771 			       isonum_733(isodir->extent) + isonum_711(isodir->ext_attr_length),
772 			       ifhp->ifid_start);
773 			return (ESTALE);
774 		}
775 #endif
776 	} else
777 		bp = NULL;
778 
779 	ip->i_mnt = imp;
780 
781 	if (relocated) {
782 		/*
783 		 * On relocated directories we must
784 		 * read the `.' entry out of a dir.
785 		 */
786 		ip->iso_start = ino >> imp->im_bshift;
787 		if (bp != NULL)
788 			brelse(bp);
789 		if ((error = cd9660_blkatoff(vp, (off_t)0, NULL, &bp)) != 0) {
790 			vput(vp);
791 			return (error);
792 		}
793 		isodir = (struct iso_directory_record *)bp->b_data;
794 	}
795 
796 	ip->iso_extent = isonum_733(isodir->extent);
797 	ip->i_size = isonum_733(isodir->size);
798 	ip->iso_start = isonum_711(isodir->ext_attr_length) + ip->iso_extent;
799 
800 	/*
801 	 * Setup time stamp, attribute
802 	 */
803 	vp->v_type = VNON;
804 	switch (imp->iso_ftype) {
805 	default:	/* ISO_FTYPE_9660 */
806 	    {
807 		struct buf *bp2;
808 		int off;
809 		if ((imp->im_flags & ISOFSMNT_EXTATT)
810 		    && (off = isonum_711(isodir->ext_attr_length)))
811 			cd9660_blkatoff(vp, (off_t)-(off << imp->im_bshift), NULL,
812 				     &bp2);
813 		else
814 			bp2 = NULL;
815 		cd9660_defattr(isodir, ip, bp2, ISO_FTYPE_9660);
816 		cd9660_deftstamp(isodir, ip, bp2, ISO_FTYPE_9660);
817 		if (bp2)
818 			brelse(bp2);
819 		break;
820 	    }
821 	case ISO_FTYPE_RRIP:
822 		cd9660_rrip_analyze(isodir, ip, imp);
823 		break;
824 	}
825 
826 	brelse(bp);
827 
828 	/*
829 	 * Initialize the associated vnode
830 	 */
831 	switch (vp->v_type = IFTOVT(ip->inode.iso_mode)) {
832 	case VFIFO:
833 		vp->v_op = &cd9660_fifoops;
834 		break;
835 	default:
836 		VN_LOCK_ASHARE(vp);
837 		break;
838 	}
839 
840 	if (ip->iso_extent == imp->root_extent)
841 		vp->v_vflag |= VV_ROOT;
842 
843 	/*
844 	 * XXX need generation number?
845 	 */
846 
847 	vn_set_state(vp, VSTATE_CONSTRUCTED);
848 	*vpp = vp;
849 	return (0);
850 }
851