xref: /openbsd/sys/dev/vnd.c (revision 958ded8a)
1 /*	$OpenBSD: vnd.c,v 1.181 2023/05/14 18:34:02 krw Exp $	*/
2 /*	$NetBSD: vnd.c,v 1.26 1996/03/30 23:06:11 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1988 University of Utah.
6  * Copyright (c) 1990, 1993
7  *	The Regents of the University of California.  All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * the Systems Programming Group of the University of Utah Computer
11  * Science Department.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 /*
39  * There is a security issue involved with this driver.
40  *
41  * Once mounted all access to the contents of the "mapped" file via
42  * the special file is controlled by the permissions on the special
43  * file, the protection of the mapped file is ignored (effectively,
44  * by using root credentials in all transactions).
45  *
46  */
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/namei.h>
51 #include <sys/proc.h>
52 #include <sys/errno.h>
53 #include <sys/limits.h>
54 #include <sys/buf.h>
55 #include <sys/malloc.h>
56 #include <sys/ioctl.h>
57 #include <sys/disklabel.h>
58 #include <sys/device.h>
59 #include <sys/disk.h>
60 #include <sys/stat.h>
61 #include <sys/vnode.h>
62 #include <sys/fcntl.h>
63 #include <sys/uio.h>
64 #include <sys/conf.h>
65 #include <sys/dkio.h>
66 #include <sys/specdev.h>
67 
68 #include <crypto/blf.h>
69 
70 #include <dev/vndioctl.h>
71 
72 #ifdef VNDDEBUG
73 int vnddebug = 0x00;
74 #define	VDB_FOLLOW	0x01
75 #define	VDB_INIT	0x02
76 #define	VDB_IO		0x04
77 #define	DNPRINTF(f, p...)	do { if ((f) & vnddebug) printf(p); } while (0)
78 #else
79 #define	DNPRINTF(f, p...)	/* nothing */
80 #endif	/* VNDDEBUG */
81 
82 struct vnd_softc {
83 	struct device	 sc_dev;
84 	struct disk	 sc_dk;
85 
86 	char		 sc_file[VNDNLEN];	/* file we're covering */
87 	int		 sc_flags;		/* flags */
88 	uint16_t	 sc_type;		/* d_type we are emulating */
89 	size_t		 sc_size;		/* size of vnd in sectors */
90 	size_t		 sc_secsize;		/* sector size in bytes */
91 	size_t		 sc_nsectors;		/* # of sectors per track */
92 	size_t		 sc_ntracks;		/* # of tracks per cylinder */
93 	struct vnode	*sc_vp;			/* vnode */
94 	struct ucred	*sc_cred;		/* credentials */
95 	blf_ctx		*sc_keyctx;		/* key context */
96 };
97 
98 /* sc_flags */
99 #define	VNF_INITED	0x0001
100 #define	VNF_HAVELABEL	0x0002
101 #define	VNF_READONLY	0x0004
102 
103 #define	VNDRW(v)	((v)->sc_flags & VNF_READONLY ? FREAD : FREAD|FWRITE)
104 
105 struct vnd_softc *vnd_softc;
106 int numvnd = 0;
107 
108 /* called by main() at boot time */
109 void	vndattach(int);
110 
111 void	vndclear(struct vnd_softc *);
112 int	vndsetcred(struct proc *p, struct vnode *, struct vnd_ioctl *,
113 	    struct ucred **);
114 int	vndgetdisklabel(dev_t, struct vnd_softc *, struct disklabel *, int);
115 void	vndencrypt(struct vnd_softc *, caddr_t, size_t, daddr_t, int);
116 void	vndencryptbuf(struct vnd_softc *, struct buf *, int);
117 size_t	vndbdevsize(struct vnode *, struct proc *);
118 
119 void
vndencrypt(struct vnd_softc * sc,caddr_t addr,size_t size,daddr_t off,int encrypt)120 vndencrypt(struct vnd_softc *sc, caddr_t addr, size_t size, daddr_t off,
121     int encrypt)
122 {
123 	int i, bsize;
124 	u_char iv[8];
125 
126 	bsize = dbtob(1);
127 	for (i = 0; i < size/bsize; i++) {
128 		memset(iv, 0, sizeof(iv));
129 		memcpy(iv, &off, sizeof(off));
130 		blf_ecb_encrypt(sc->sc_keyctx, iv, sizeof(iv));
131 		if (encrypt)
132 			blf_cbc_encrypt(sc->sc_keyctx, iv, addr, bsize);
133 		else
134 			blf_cbc_decrypt(sc->sc_keyctx, iv, addr, bsize);
135 
136 		addr += bsize;
137 		off++;
138 	}
139 }
140 
141 void
vndencryptbuf(struct vnd_softc * sc,struct buf * bp,int encrypt)142 vndencryptbuf(struct vnd_softc *sc, struct buf *bp, int encrypt)
143 {
144 	vndencrypt(sc, bp->b_data, bp->b_bcount, bp->b_blkno, encrypt);
145 }
146 
147 void
vndattach(int num)148 vndattach(int num)
149 {
150 	char *mem;
151 	int i;
152 
153 	if (num <= 0)
154 		return;
155 	mem = mallocarray(num, sizeof(struct vnd_softc), M_DEVBUF,
156 	    M_NOWAIT | M_ZERO);
157 	if (mem == NULL) {
158 		printf("WARNING: no memory for vnode disks\n");
159 		return;
160 	}
161 	vnd_softc = (struct vnd_softc *)mem;
162 	for (i = 0; i < num; i++) {
163 		struct vnd_softc *sc = &vnd_softc[i];
164 
165 		sc->sc_dev.dv_unit = i;
166 		snprintf(sc->sc_dev.dv_xname, sizeof(sc->sc_dev.dv_xname),
167 		    "vnd%d", i);
168 		disk_construct(&sc->sc_dk);
169 		device_ref(&sc->sc_dev);
170 	}
171 	numvnd = num;
172 }
173 
174 int
vndopen(dev_t dev,int flags,int mode,struct proc * p)175 vndopen(dev_t dev, int flags, int mode, struct proc *p)
176 {
177 	int unit = DISKUNIT(dev);
178 	struct vnd_softc *sc;
179 	int error = 0, part;
180 
181 	DNPRINTF(VDB_FOLLOW, "vndopen(%x, %x, %x, %p)\n", dev, flags, mode, p);
182 
183 	if (unit >= numvnd)
184 		return (ENXIO);
185 	sc = &vnd_softc[unit];
186 
187 	if ((error = disk_lock(&sc->sc_dk)) != 0)
188 		return (error);
189 
190 	if ((flags & FWRITE) && (sc->sc_flags & VNF_READONLY)) {
191 		error = EROFS;
192 		goto bad;
193 	}
194 
195 	if ((sc->sc_flags & VNF_INITED) &&
196 	    (sc->sc_flags & VNF_HAVELABEL) == 0 &&
197 	    sc->sc_dk.dk_openmask == 0) {
198 		sc->sc_flags |= VNF_HAVELABEL;
199 		vndgetdisklabel(dev, sc, sc->sc_dk.dk_label, 0);
200 	}
201 
202 	part = DISKPART(dev);
203 	error = disk_openpart(&sc->sc_dk, part, mode,
204 	    (sc->sc_flags & VNF_HAVELABEL) != 0);
205 
206 bad:
207 	disk_unlock(&sc->sc_dk);
208 	return (error);
209 }
210 
211 /*
212  * Load the label information on the named device
213  */
214 int
vndgetdisklabel(dev_t dev,struct vnd_softc * sc,struct disklabel * lp,int spoofonly)215 vndgetdisklabel(dev_t dev, struct vnd_softc *sc, struct disklabel *lp,
216     int spoofonly)
217 {
218 	memset(lp, 0, sizeof(struct disklabel));
219 
220 	lp->d_secsize = sc->sc_secsize;
221 	lp->d_nsectors = sc->sc_nsectors;
222 	lp->d_ntracks = sc->sc_ntracks;
223 	lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors;
224 	if (lp->d_secpercyl)
225 		lp->d_ncylinders = sc->sc_size / lp->d_secpercyl;
226 
227 	strncpy(lp->d_typename, "vnd device", sizeof(lp->d_typename));
228 	lp->d_type = sc->sc_type;
229 	strncpy(lp->d_packname, "fictitious", sizeof(lp->d_packname));
230 	DL_SETDSIZE(lp, sc->sc_size);
231 	lp->d_version = 1;
232 
233 	lp->d_magic = DISKMAGIC;
234 	lp->d_magic2 = DISKMAGIC;
235 	lp->d_checksum = dkcksum(lp);
236 
237 	/* Call the generic disklabel extraction routine */
238 	return readdisklabel(DISKLABELDEV(dev), vndstrategy, lp, spoofonly);
239 }
240 
241 int
vndclose(dev_t dev,int flags,int mode,struct proc * p)242 vndclose(dev_t dev, int flags, int mode, struct proc *p)
243 {
244 	int unit = DISKUNIT(dev);
245 	struct vnd_softc *sc;
246 	int part;
247 
248 	DNPRINTF(VDB_FOLLOW, "vndclose(%x, %x, %x, %p)\n", dev, flags, mode, p);
249 
250 	if (unit >= numvnd)
251 		return (ENXIO);
252 	sc = &vnd_softc[unit];
253 
254 	disk_lock_nointr(&sc->sc_dk);
255 
256 	part = DISKPART(dev);
257 
258 	disk_closepart(&sc->sc_dk, part, mode);
259 
260 #if 0
261 	if (sc->sc_dk.dk_openmask == 0)
262 		sc->sc_flags &= ~VNF_HAVELABEL;
263 #endif
264 
265 	disk_unlock(&sc->sc_dk);
266 	return (0);
267 }
268 
269 void
vndstrategy(struct buf * bp)270 vndstrategy(struct buf *bp)
271 {
272 	int unit = DISKUNIT(bp->b_dev);
273 	struct vnd_softc *sc;
274 	struct partition *p;
275 	off_t off;
276 	long origbcount;
277 	int s;
278 
279 	DNPRINTF(VDB_FOLLOW, "vndstrategy(%p): unit %d\n", bp, unit);
280 
281 	if (unit >= numvnd) {
282 		bp->b_error = ENXIO;
283 		goto bad;
284 	}
285 	sc = &vnd_softc[unit];
286 
287 	if ((sc->sc_flags & VNF_HAVELABEL) == 0) {
288 		bp->b_error = ENXIO;
289 		goto bad;
290 	}
291 
292 	/*
293 	 * Many of the distrib scripts assume they can issue arbitrary
294 	 * sized requests to raw vnd devices irrespective of the
295 	 * emulated disk geometry.
296 	 *
297 	 * To continue supporting this, round the block count up to a
298 	 * multiple of d_secsize for bounds_check_with_label(), and
299 	 * then restore afterwards.
300 	 *
301 	 * We only do this for non-encrypted vnd, because encryption
302 	 * requires operating on blocks at a time.
303 	 */
304 	origbcount = bp->b_bcount;
305 	if (sc->sc_keyctx == NULL) {
306 		u_int32_t secsize = sc->sc_dk.dk_label->d_secsize;
307 		bp->b_bcount = ((origbcount + secsize - 1) & ~(secsize - 1));
308 #ifdef DIAGNOSTIC
309 		if (bp->b_bcount != origbcount) {
310 			struct process *curpr = curproc->p_p;
311 			printf("%s: sloppy %s from proc %d (%s): "
312 			    "blkno %lld bcount %ld\n", sc->sc_dev.dv_xname,
313 			    (bp->b_flags & B_READ) ? "read" : "write",
314 			    curpr->ps_pid, curpr->ps_comm,
315 			    (long long)bp->b_blkno, origbcount);
316 		}
317 #endif
318 	}
319 
320 	if (bounds_check_with_label(bp, sc->sc_dk.dk_label) == -1) {
321 		bp->b_resid = bp->b_bcount = origbcount;
322 		goto done;
323 	}
324 
325 	if (origbcount < bp->b_bcount)
326 		bp->b_bcount = origbcount;
327 
328 	p = &sc->sc_dk.dk_label->d_partitions[DISKPART(bp->b_dev)];
329 	off = DL_GETPOFFSET(p) * sc->sc_dk.dk_label->d_secsize +
330 	    (u_int64_t)bp->b_blkno * DEV_BSIZE;
331 
332 	if (sc->sc_keyctx && !(bp->b_flags & B_READ))
333 		vndencryptbuf(sc, bp, 1);
334 
335 	/*
336 	 * Use IO_NOLIMIT because upper layer has already checked I/O
337 	 * for limits, so there is no need to do it again.
338 	 *
339 	 * We use IO_NOCACHE because this data should be cached at the
340 	 * upper layer, so there is no need to cache it again.
341 	 */
342 	bp->b_error = vn_rdwr((bp->b_flags & B_READ) ? UIO_READ : UIO_WRITE,
343 	    sc->sc_vp, bp->b_data, bp->b_bcount, off, UIO_SYSSPACE,
344 	    IO_NOCACHE | IO_SYNC | IO_NOLIMIT, sc->sc_cred, &bp->b_resid, curproc);
345 	if (bp->b_error)
346 		bp->b_flags |= B_ERROR;
347 
348 	/* Data in buffer cache needs to be in clear */
349 	if (sc->sc_keyctx)
350 		vndencryptbuf(sc, bp, 0);
351 
352 	goto done;
353 
354  bad:
355 	bp->b_flags |= B_ERROR;
356 	bp->b_resid = bp->b_bcount;
357  done:
358 	s = splbio();
359 	biodone(bp);
360 	splx(s);
361 }
362 
363 int
vndread(dev_t dev,struct uio * uio,int flags)364 vndread(dev_t dev, struct uio *uio, int flags)
365 {
366 	return (physio(vndstrategy, dev, B_READ, minphys, uio));
367 }
368 
369 int
vndwrite(dev_t dev,struct uio * uio,int flags)370 vndwrite(dev_t dev, struct uio *uio, int flags)
371 {
372 	return (physio(vndstrategy, dev, B_WRITE, minphys, uio));
373 }
374 
375 size_t
vndbdevsize(struct vnode * vp,struct proc * p)376 vndbdevsize(struct vnode *vp, struct proc *p)
377 {
378 	struct partinfo pi;
379 	struct bdevsw *bsw;
380 	dev_t dev;
381 
382 	dev = vp->v_rdev;
383 	bsw = bdevsw_lookup(dev);
384 	if (bsw->d_ioctl == NULL)
385 		return (0);
386 	if (bsw->d_ioctl(dev, DIOCGPART, (caddr_t)&pi, FREAD, p))
387 		return (0);
388 	DNPRINTF(VDB_INIT, "vndbdevsize: size %llu secsize %u\n",
389 	    DL_GETPSIZE(pi.part), pi.disklab->d_secsize);
390 	return (DL_GETPSIZE(pi.part));
391 }
392 
393 int
vndioctl(dev_t dev,u_long cmd,caddr_t addr,int flag,struct proc * p)394 vndioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
395 {
396 	int unit = DISKUNIT(dev);
397 	struct disklabel *lp;
398 	struct vnd_softc *sc;
399 	struct vnd_ioctl *vio;
400 	struct vnd_user *vnu;
401 	struct vattr vattr;
402 	int error, part, pmask;
403 
404 	DNPRINTF(VDB_FOLLOW, "vndioctl(%x, %lx, %p, %x, %p): unit %d\n",
405 	    dev, cmd, addr, flag, p, unit);
406 
407 	error = suser(p);
408 	if (error)
409 		return (error);
410 	if (unit >= numvnd)
411 		return (ENXIO);
412 
413 	sc = &vnd_softc[unit];
414 	vio = (struct vnd_ioctl *)addr;
415 	switch (cmd) {
416 
417 	case VNDIOCSET:
418 	    {
419 		char name[VNDNLEN], key[BLF_MAXUTILIZED];
420 		struct nameidata nd;
421 		struct ucred *cred = NULL;
422 		size_t size;
423 		int vplocked;
424 		int rw;
425 
426 		if (sc->sc_flags & VNF_INITED)
427 			return (EBUSY);
428 
429 		/* Geometry eventually has to fit into label fields */
430 		if (vio->vnd_secsize > UINT_MAX ||
431 		    vio->vnd_secsize == 0 ||
432 		    vio->vnd_ntracks > UINT_MAX ||
433 		    vio->vnd_nsectors > UINT_MAX)
434 			return (EINVAL);
435 
436 		if ((error = copyinstr(vio->vnd_file, name,
437 		    sizeof(name), NULL)))
438 			return (error);
439 
440 		if (vio->vnd_keylen > 0) {
441 			if (vio->vnd_keylen > sizeof(key))
442 				vio->vnd_keylen = sizeof(key);
443 
444 			if ((error = copyin(vio->vnd_key, key,
445 			    vio->vnd_keylen)) != 0)
446 				return (error);
447 		}
448 
449 		/*
450 		 * Open for read and write first. This lets vn_open() weed out
451 		 * directories, sockets, etc. so we don't have to worry about
452 		 * them.
453 		 */
454 		NDINIT(&nd, 0, 0, UIO_SYSSPACE, name, p);
455 		nd.ni_unveil = UNVEIL_READ | UNVEIL_WRITE;
456 		rw = FREAD|FWRITE;
457 		error = vn_open(&nd, FREAD|FWRITE, 0);
458 		if (error == EROFS) {
459 			NDINIT(&nd, 0, 0, UIO_SYSSPACE, name, p);
460 			nd.ni_unveil = UNVEIL_READ | UNVEIL_WRITE;
461 			rw = FREAD;
462 			error = vn_open(&nd, FREAD, 0);
463 		}
464 		if (error)
465 			return (error);
466 		vplocked = 1;
467 
468 		error = VOP_GETATTR(nd.ni_vp, &vattr, p->p_ucred, p);
469 		if (error) {
470 fail:
471 			if (vplocked)
472 				VOP_UNLOCK(nd.ni_vp);
473 			vn_close(nd.ni_vp, rw, p->p_ucred, p);
474 			if (cred != NULL)
475 				crfree(cred);
476 			return (error);
477 		}
478 
479 		/* Cannot put a vnd on top of a vnd */
480 		if (major(vattr.va_fsid) == major(dev)) {
481 			error = EINVAL;
482 			goto fail;
483 		}
484 
485 		if ((error = vndsetcred(p, nd.ni_vp, vio, &cred)) != 0)
486 			goto fail;
487 
488 		VOP_UNLOCK(nd.ni_vp);
489 		vplocked = 0;
490 
491 		if (nd.ni_vp->v_type == VBLK) {
492 			size = vndbdevsize(nd.ni_vp, p);
493 			/* XXX is size 0 ok? */
494 		} else
495 			size = vattr.va_size / vio->vnd_secsize;
496 
497 		if ((error = disk_lock(&sc->sc_dk)) != 0)
498 			goto fail;
499 		if (sc->sc_flags & VNF_INITED) {
500 			disk_unlock(&sc->sc_dk);
501 			error = EBUSY;
502 			goto fail;
503 		}
504 
505 		/* Set geometry for device. */
506 		sc->sc_type = vio->vnd_type;
507 		sc->sc_secsize = vio->vnd_secsize;
508 		sc->sc_ntracks = vio->vnd_ntracks;
509 		sc->sc_nsectors = vio->vnd_nsectors;
510 		sc->sc_size = size;
511 
512 		if (rw == FREAD)
513 			sc->sc_flags |= VNF_READONLY;
514 		else
515 			sc->sc_flags &= ~VNF_READONLY;
516 
517 		memcpy(sc->sc_file, name, sizeof(sc->sc_file));
518 
519 		if (vio->vnd_keylen > 0) {
520 			sc->sc_keyctx = malloc(sizeof(*sc->sc_keyctx), M_DEVBUF,
521 			    M_WAITOK);
522 			blf_key(sc->sc_keyctx, key, vio->vnd_keylen);
523 			explicit_bzero(key, vio->vnd_keylen);
524 		} else
525 			sc->sc_keyctx = NULL;
526 
527 		sc->sc_vp = nd.ni_vp;
528 		sc->sc_cred = cred;
529 		vio->vnd_size = sc->sc_size * sc->sc_secsize;
530 		sc->sc_flags |= VNF_INITED;
531 
532 		DNPRINTF(VDB_INIT, "vndioctl: SET vp %p size %llx\n",
533 		    sc->sc_vp, (unsigned long long)sc->sc_size);
534 
535 		/* Attach the disk. */
536 		sc->sc_dk.dk_name = sc->sc_dev.dv_xname;
537 		disk_attach(&sc->sc_dev, &sc->sc_dk);
538 
539 		disk_unlock(&sc->sc_dk);
540 
541 		break;
542 	    }
543 	case VNDIOCCLR:
544 		if ((error = disk_lock(&sc->sc_dk)) != 0)
545 			return (error);
546 		if ((sc->sc_flags & VNF_INITED) == 0) {
547 			disk_unlock(&sc->sc_dk);
548 			return (ENXIO);
549 		}
550 
551 		/*
552 		 * Don't unconfigure if any other partitions are open
553 		 * or if both the character and block flavors of this
554 		 * partition are open.
555 		 */
556 		part = DISKPART(dev);
557 		pmask = (1 << part);
558 		if ((sc->sc_dk.dk_openmask & ~pmask) ||
559 		    ((sc->sc_dk.dk_bopenmask & pmask) &&
560 		    (sc->sc_dk.dk_copenmask & pmask))) {
561 			disk_unlock(&sc->sc_dk);
562 			return (EBUSY);
563 		}
564 
565 		vndclear(sc);
566 		DNPRINTF(VDB_INIT, "vndioctl: CLRed\n");
567 
568 		/* Free crypto key */
569 		if (sc->sc_keyctx) {
570 			explicit_bzero(sc->sc_keyctx, sizeof(*sc->sc_keyctx));
571 			free(sc->sc_keyctx, M_DEVBUF, sizeof(*sc->sc_keyctx));
572 		}
573 
574 		/* Detach the disk. */
575 		disk_detach(&sc->sc_dk);
576 		disk_unlock(&sc->sc_dk);
577 		break;
578 
579 	case VNDIOCGET:
580 		vnu = (struct vnd_user *)addr;
581 
582 		if (vnu->vnu_unit == -1)
583 			vnu->vnu_unit = unit;
584 		if (vnu->vnu_unit >= numvnd)
585 			return (ENXIO);
586 		if (vnu->vnu_unit < 0)
587 			return (EINVAL);
588 
589 		sc = &vnd_softc[vnu->vnu_unit];
590 
591 		if (sc->sc_flags & VNF_INITED) {
592 			error = VOP_GETATTR(sc->sc_vp, &vattr, p->p_ucred, p);
593 			if (error)
594 				return (error);
595 
596 			strlcpy(vnu->vnu_file, sc->sc_file,
597 			    sizeof(vnu->vnu_file));
598 			vnu->vnu_dev = vattr.va_fsid;
599 			vnu->vnu_ino = vattr.va_fileid;
600 		} else {
601 			vnu->vnu_dev = 0;
602 			vnu->vnu_ino = 0;
603 		}
604 
605 		break;
606 
607 	case DIOCRLDINFO:
608 		if ((sc->sc_flags & VNF_HAVELABEL) == 0)
609 			return (ENOTTY);
610 		lp = malloc(sizeof(*lp), M_TEMP, M_WAITOK);
611 		vndgetdisklabel(dev, sc, lp, 0);
612 		*(sc->sc_dk.dk_label) = *lp;
613 		free(lp, M_TEMP, sizeof(*lp));
614 		return (0);
615 
616 	case DIOCGPDINFO:
617 		if ((sc->sc_flags & VNF_HAVELABEL) == 0)
618 			return (ENOTTY);
619 		vndgetdisklabel(dev, sc, (struct disklabel *)addr, 1);
620 		return (0);
621 
622 	case DIOCGDINFO:
623 		if ((sc->sc_flags & VNF_HAVELABEL) == 0)
624 			return (ENOTTY);
625 		*(struct disklabel *)addr = *(sc->sc_dk.dk_label);
626 		return (0);
627 
628 	case DIOCGPART:
629 		if ((sc->sc_flags & VNF_HAVELABEL) == 0)
630 			return (ENOTTY);
631 		((struct partinfo *)addr)->disklab = sc->sc_dk.dk_label;
632 		((struct partinfo *)addr)->part =
633 		    &sc->sc_dk.dk_label->d_partitions[DISKPART(dev)];
634 		return (0);
635 
636 	case DIOCWDINFO:
637 	case DIOCSDINFO:
638 		if ((sc->sc_flags & VNF_HAVELABEL) == 0)
639 			return (ENOTTY);
640 		if ((flag & FWRITE) == 0)
641 			return (EBADF);
642 
643 		if ((error = disk_lock(&sc->sc_dk)) != 0)
644 			return (error);
645 
646 		error = setdisklabel(sc->sc_dk.dk_label,
647 		    (struct disklabel *)addr, /* sc->sc_dk.dk_openmask */ 0);
648 		if (error == 0) {
649 			if (cmd == DIOCWDINFO)
650 				error = writedisklabel(DISKLABELDEV(dev),
651 				    vndstrategy, sc->sc_dk.dk_label);
652 		}
653 
654 		disk_unlock(&sc->sc_dk);
655 		return (error);
656 
657 	default:
658 		return (ENOTTY);
659 	}
660 
661 	return (0);
662 }
663 
664 /*
665  * Duplicate the current processes' credentials.  Since we are called only
666  * as the result of a SET ioctl and only root can do that, any future access
667  * to this "disk" is essentially as root.  Note that credentials may change
668  * if some other uid can write directly to the mapped file (NFS).
669  */
670 int
vndsetcred(struct proc * p,struct vnode * vp,struct vnd_ioctl * vio,struct ucred ** newcredp)671 vndsetcred(struct proc *p, struct vnode *vp, struct vnd_ioctl *vio,
672     struct ucred **newcredp)
673 {
674 	void *buf;
675 	size_t size;
676 	struct ucred *new;
677 	int error;
678 
679 	new = crdup(p->p_ucred);
680 	buf = malloc(DEV_BSIZE, M_TEMP, M_WAITOK);
681 	size = DEV_BSIZE;
682 
683 	/* XXX: Horrible kludge to establish credentials for NFS */
684 	error = vn_rdwr(UIO_READ, vp, buf, size, 0, UIO_SYSSPACE, 0,
685 	    new, NULL, curproc);
686 
687 	free(buf, M_TEMP, DEV_BSIZE);
688 	if (error == 0)
689 		*newcredp = new;
690 	else
691 		crfree(new);
692 	return (error);
693 }
694 
695 void
vndclear(struct vnd_softc * sc)696 vndclear(struct vnd_softc *sc)
697 {
698 	struct vnode *vp = sc->sc_vp;
699 	struct proc *p = curproc;		/* XXX */
700 
701 	DNPRINTF(VDB_FOLLOW, "vndclear(%p): vp %p\n", sc, vp);
702 
703 	if (vp == NULL)
704 		panic("vndioctl: null vp");
705 	(void) vn_close(vp, VNDRW(sc), sc->sc_cred, p);
706 	crfree(sc->sc_cred);
707 	sc->sc_flags = 0;
708 	sc->sc_vp = NULL;
709 	sc->sc_cred = NULL;
710 	sc->sc_size = 0;
711 	memset(sc->sc_file, 0, sizeof(sc->sc_file));
712 }
713 
714 daddr_t
vndsize(dev_t dev)715 vndsize(dev_t dev)
716 {
717 	/* We don't support swapping to vnd anymore. */
718 	return (-1);
719 }
720 
721 int
vnddump(dev_t dev,daddr_t blkno,caddr_t va,size_t size)722 vnddump(dev_t dev, daddr_t blkno, caddr_t va, size_t size)
723 {
724 	/* Not implemented. */
725 	return (ENXIO);
726 }
727