xref: /netbsd-src/sys/dev/cgd.c (revision 1b9578b8c2c1f848eeb16dabbfd7d1f0d9fdefbd)
1 /* $NetBSD: cgd.c,v 1.74 2011/06/21 06:23:38 jruoho Exp $ */
2 
3 /*-
4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Roland C. Dowdeswell.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.74 2011/06/21 06:23:38 jruoho Exp $");
34 
35 #include <sys/types.h>
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/proc.h>
39 #include <sys/errno.h>
40 #include <sys/buf.h>
41 #include <sys/bufq.h>
42 #include <sys/malloc.h>
43 #include <sys/module.h>
44 #include <sys/pool.h>
45 #include <sys/ioctl.h>
46 #include <sys/device.h>
47 #include <sys/disk.h>
48 #include <sys/disklabel.h>
49 #include <sys/fcntl.h>
50 #include <sys/namei.h> /* for pathbuf */
51 #include <sys/vnode.h>
52 #include <sys/conf.h>
53 #include <sys/syslog.h>
54 
55 #include <dev/dkvar.h>
56 #include <dev/cgdvar.h>
57 
58 /* Entry Point Functions */
59 
60 void	cgdattach(int);
61 
62 static dev_type_open(cgdopen);
63 static dev_type_close(cgdclose);
64 static dev_type_read(cgdread);
65 static dev_type_write(cgdwrite);
66 static dev_type_ioctl(cgdioctl);
67 static dev_type_strategy(cgdstrategy);
68 static dev_type_dump(cgddump);
69 static dev_type_size(cgdsize);
70 
71 const struct bdevsw cgd_bdevsw = {
72 	cgdopen, cgdclose, cgdstrategy, cgdioctl,
73 	cgddump, cgdsize, D_DISK
74 };
75 
76 const struct cdevsw cgd_cdevsw = {
77 	cgdopen, cgdclose, cgdread, cgdwrite, cgdioctl,
78 	nostop, notty, nopoll, nommap, nokqfilter, D_DISK
79 };
80 
81 static int cgd_match(device_t, cfdata_t, void *);
82 static void cgd_attach(device_t, device_t, void *);
83 static int cgd_detach(device_t, int);
84 static struct cgd_softc	*cgd_spawn(int);
85 static int cgd_destroy(device_t);
86 
87 /* Internal Functions */
88 
89 static int	cgdstart(struct dk_softc *, struct buf *);
90 static void	cgdiodone(struct buf *);
91 
92 static int	cgd_ioctl_set(struct cgd_softc *, void *, struct lwp *);
93 static int	cgd_ioctl_clr(struct cgd_softc *, struct lwp *);
94 static int	cgdinit(struct cgd_softc *, const char *, struct vnode *,
95 			struct lwp *);
96 static void	cgd_cipher(struct cgd_softc *, void *, void *,
97 			   size_t, daddr_t, size_t, int);
98 
99 /* Pseudo-disk Interface */
100 
101 static struct dk_intf the_dkintf = {
102 	DTYPE_CGD,
103 	"cgd",
104 	cgdopen,
105 	cgdclose,
106 	cgdstrategy,
107 	cgdstart,
108 };
109 static struct dk_intf *di = &the_dkintf;
110 
111 static struct dkdriver cgddkdriver = {
112 	.d_strategy = cgdstrategy,
113 	.d_minphys = minphys,
114 };
115 
116 CFATTACH_DECL3_NEW(cgd, sizeof(struct cgd_softc),
117     cgd_match, cgd_attach, cgd_detach, NULL, NULL, NULL, DVF_DETACH_SHUTDOWN);
118 extern struct cfdriver cgd_cd;
119 
120 /* DIAGNOSTIC and DEBUG definitions */
121 
122 #if defined(CGDDEBUG) && !defined(DEBUG)
123 #define DEBUG
124 #endif
125 
126 #ifdef DEBUG
127 int cgddebug = 0;
128 
129 #define CGDB_FOLLOW	0x1
130 #define CGDB_IO	0x2
131 #define CGDB_CRYPTO	0x4
132 
133 #define IFDEBUG(x,y)		if (cgddebug & (x)) y
134 #define DPRINTF(x,y)		IFDEBUG(x, printf y)
135 #define DPRINTF_FOLLOW(y)	DPRINTF(CGDB_FOLLOW, y)
136 
137 static void	hexprint(const char *, void *, int);
138 
139 #else
140 #define IFDEBUG(x,y)
141 #define DPRINTF(x,y)
142 #define DPRINTF_FOLLOW(y)
143 #endif
144 
145 #ifdef DIAGNOSTIC
146 #define DIAGPANIC(x)		panic x
147 #define DIAGCONDPANIC(x,y)	if (x) panic y
148 #else
149 #define DIAGPANIC(x)
150 #define DIAGCONDPANIC(x,y)
151 #endif
152 
153 /* Global variables */
154 
155 /* Utility Functions */
156 
157 #define CGDUNIT(x)		DISKUNIT(x)
158 #define GETCGD_SOFTC(_cs, x)	if (!((_cs) = getcgd_softc(x))) return ENXIO
159 
160 /* The code */
161 
162 static struct cgd_softc *
163 getcgd_softc(dev_t dev)
164 {
165 	int	unit = CGDUNIT(dev);
166 	struct cgd_softc *sc;
167 
168 	DPRINTF_FOLLOW(("getcgd_softc(0x%"PRIx64"): unit = %d\n", dev, unit));
169 
170 	sc = device_lookup_private(&cgd_cd, unit);
171 	if (sc == NULL)
172 		sc = cgd_spawn(unit);
173 	return sc;
174 }
175 
176 static int
177 cgd_match(device_t self, cfdata_t cfdata, void *aux)
178 {
179 
180 	return 1;
181 }
182 
183 static void
184 cgd_attach(device_t parent, device_t self, void *aux)
185 {
186 	struct cgd_softc *sc = device_private(self);
187 
188 	sc->sc_dev = self;
189 	simple_lock_init(&sc->sc_slock);
190 	dk_sc_init(&sc->sc_dksc, sc, device_xname(sc->sc_dev));
191 	disk_init(&sc->sc_dksc.sc_dkdev, sc->sc_dksc.sc_xname, &cgddkdriver);
192 
193 	 if (!pmf_device_register(self, NULL, NULL))
194 		aprint_error_dev(self, "unable to register power management hooks\n");
195 }
196 
197 
198 static int
199 cgd_detach(device_t self, int flags)
200 {
201 	int ret;
202 	const int pmask = 1 << RAW_PART;
203 	struct cgd_softc *sc = device_private(self);
204 	struct dk_softc *dksc = &sc->sc_dksc;
205 
206 	if (DK_BUSY(dksc, pmask))
207 		return EBUSY;
208 
209 	if ((dksc->sc_flags & DKF_INITED) != 0 &&
210 	    (ret = cgd_ioctl_clr(sc, curlwp)) != 0)
211 		return ret;
212 
213 	disk_destroy(&dksc->sc_dkdev);
214 
215 	return 0;
216 }
217 
218 void
219 cgdattach(int num)
220 {
221 	int error;
222 
223 	error = config_cfattach_attach(cgd_cd.cd_name, &cgd_ca);
224 	if (error != 0)
225 		aprint_error("%s: unable to register cfattach\n",
226 		    cgd_cd.cd_name);
227 }
228 
229 static struct cgd_softc *
230 cgd_spawn(int unit)
231 {
232 	cfdata_t cf;
233 
234 	cf = malloc(sizeof(*cf), M_DEVBUF, M_WAITOK);
235 	cf->cf_name = cgd_cd.cd_name;
236 	cf->cf_atname = cgd_cd.cd_name;
237 	cf->cf_unit = unit;
238 	cf->cf_fstate = FSTATE_STAR;
239 
240 	return device_private(config_attach_pseudo(cf));
241 }
242 
243 static int
244 cgd_destroy(device_t dev)
245 {
246 	int error;
247 	cfdata_t cf;
248 
249 	cf = device_cfdata(dev);
250 	error = config_detach(dev, DETACH_QUIET);
251 	if (error)
252 		return error;
253 	free(cf, M_DEVBUF);
254 	return 0;
255 }
256 
257 static int
258 cgdopen(dev_t dev, int flags, int fmt, struct lwp *l)
259 {
260 	struct	cgd_softc *cs;
261 
262 	DPRINTF_FOLLOW(("cgdopen(0x%"PRIx64", %d)\n", dev, flags));
263 	GETCGD_SOFTC(cs, dev);
264 	return dk_open(di, &cs->sc_dksc, dev, flags, fmt, l);
265 }
266 
267 static int
268 cgdclose(dev_t dev, int flags, int fmt, struct lwp *l)
269 {
270 	int error;
271 	struct	cgd_softc *cs;
272 	struct	dk_softc *dksc;
273 
274 	DPRINTF_FOLLOW(("cgdclose(0x%"PRIx64", %d)\n", dev, flags));
275 	GETCGD_SOFTC(cs, dev);
276 	dksc = &cs->sc_dksc;
277 	if ((error =  dk_close(di, dksc, dev, flags, fmt, l)) != 0)
278 		return error;
279 
280 	if ((dksc->sc_flags & DKF_INITED) == 0) {
281 		if ((error = cgd_destroy(cs->sc_dev)) != 0) {
282 			aprint_error_dev(cs->sc_dev,
283 			    "unable to detach instance\n");
284 			return error;
285 		}
286 	}
287 	return 0;
288 }
289 
290 static void
291 cgdstrategy(struct buf *bp)
292 {
293 	struct	cgd_softc *cs = getcgd_softc(bp->b_dev);
294 
295 	DPRINTF_FOLLOW(("cgdstrategy(%p): b_bcount = %ld\n", bp,
296 	    (long)bp->b_bcount));
297 
298 	/*
299 	 * Reject unaligned writes.  We can encrypt and decrypt only
300 	 * complete disk sectors, and we let the ciphers require their
301 	 * buffers to be aligned to 32-bit boundaries.
302 	 */
303 	if (bp->b_blkno < 0 ||
304 	    (bp->b_bcount % DEV_BSIZE) != 0 ||
305 	    ((uintptr_t)bp->b_data & 3) != 0) {
306 		bp->b_error = EINVAL;
307 		bp->b_resid = bp->b_bcount;
308 		biodone(bp);
309 		return;
310 	}
311 
312 	/* XXXrcd: Should we test for (cs != NULL)? */
313 	dk_strategy(di, &cs->sc_dksc, bp);
314 	return;
315 }
316 
317 static int
318 cgdsize(dev_t dev)
319 {
320 	struct cgd_softc *cs = getcgd_softc(dev);
321 
322 	DPRINTF_FOLLOW(("cgdsize(0x%"PRIx64")\n", dev));
323 	if (!cs)
324 		return -1;
325 	return dk_size(di, &cs->sc_dksc, dev);
326 }
327 
328 /*
329  * cgd_{get,put}data are functions that deal with getting a buffer
330  * for the new encrypted data.  We have a buffer per device so that
331  * we can ensure that we can always have a transaction in flight.
332  * We use this buffer first so that we have one less piece of
333  * malloc'ed data at any given point.
334  */
335 
336 static void *
337 cgd_getdata(struct dk_softc *dksc, unsigned long size)
338 {
339 	struct	cgd_softc *cs =dksc->sc_osc;
340 	void *	data = NULL;
341 
342 	simple_lock(&cs->sc_slock);
343 	if (cs->sc_data_used == 0) {
344 		cs->sc_data_used = 1;
345 		data = cs->sc_data;
346 	}
347 	simple_unlock(&cs->sc_slock);
348 
349 	if (data)
350 		return data;
351 
352 	return malloc(size, M_DEVBUF, M_NOWAIT);
353 }
354 
355 static void
356 cgd_putdata(struct dk_softc *dksc, void *data)
357 {
358 	struct	cgd_softc *cs =dksc->sc_osc;
359 
360 	if (data == cs->sc_data) {
361 		simple_lock(&cs->sc_slock);
362 		cs->sc_data_used = 0;
363 		simple_unlock(&cs->sc_slock);
364 	} else {
365 		free(data, M_DEVBUF);
366 	}
367 }
368 
369 static int
370 cgdstart(struct dk_softc *dksc, struct buf *bp)
371 {
372 	struct	cgd_softc *cs = dksc->sc_osc;
373 	struct	buf *nbp;
374 	void *	addr;
375 	void *	newaddr;
376 	daddr_t	bn;
377 	struct	vnode *vp;
378 
379 	DPRINTF_FOLLOW(("cgdstart(%p, %p)\n", dksc, bp));
380 	disk_busy(&dksc->sc_dkdev); /* XXX: put in dksubr.c */
381 
382 	bn = bp->b_rawblkno;
383 
384 	/*
385 	 * We attempt to allocate all of our resources up front, so that
386 	 * we can fail quickly if they are unavailable.
387 	 */
388 
389 	nbp = getiobuf(cs->sc_tvn, false);
390 	if (nbp == NULL) {
391 		disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
392 		return -1;
393 	}
394 
395 	/*
396 	 * If we are writing, then we need to encrypt the outgoing
397 	 * block into a new block of memory.  If we fail, then we
398 	 * return an error and let the dksubr framework deal with it.
399 	 */
400 	newaddr = addr = bp->b_data;
401 	if ((bp->b_flags & B_READ) == 0) {
402 		newaddr = cgd_getdata(dksc, bp->b_bcount);
403 		if (!newaddr) {
404 			putiobuf(nbp);
405 			disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
406 			return -1;
407 		}
408 		cgd_cipher(cs, newaddr, addr, bp->b_bcount, bn,
409 		    DEV_BSIZE, CGD_CIPHER_ENCRYPT);
410 	}
411 
412 	nbp->b_data = newaddr;
413 	nbp->b_flags = bp->b_flags;
414 	nbp->b_oflags = bp->b_oflags;
415 	nbp->b_cflags = bp->b_cflags;
416 	nbp->b_iodone = cgdiodone;
417 	nbp->b_proc = bp->b_proc;
418 	nbp->b_blkno = bn;
419 	nbp->b_bcount = bp->b_bcount;
420 	nbp->b_private = bp;
421 
422 	BIO_COPYPRIO(nbp, bp);
423 
424 	if ((nbp->b_flags & B_READ) == 0) {
425 		vp = nbp->b_vp;
426 		mutex_enter(vp->v_interlock);
427 		vp->v_numoutput++;
428 		mutex_exit(vp->v_interlock);
429 	}
430 	VOP_STRATEGY(cs->sc_tvn, nbp);
431 	return 0;
432 }
433 
434 static void
435 cgdiodone(struct buf *nbp)
436 {
437 	struct	buf *obp = nbp->b_private;
438 	struct	cgd_softc *cs = getcgd_softc(obp->b_dev);
439 	struct	dk_softc *dksc = &cs->sc_dksc;
440 	int s;
441 
442 	KDASSERT(cs);
443 
444 	DPRINTF_FOLLOW(("cgdiodone(%p)\n", nbp));
445 	DPRINTF(CGDB_IO, ("cgdiodone: bp %p bcount %d resid %d\n",
446 	    obp, obp->b_bcount, obp->b_resid));
447 	DPRINTF(CGDB_IO, (" dev 0x%"PRIx64", nbp %p bn %" PRId64 " addr %p bcnt %d\n",
448 	    nbp->b_dev, nbp, nbp->b_blkno, nbp->b_data,
449 	    nbp->b_bcount));
450 	if (nbp->b_error != 0) {
451 		obp->b_error = nbp->b_error;
452 		DPRINTF(CGDB_IO, ("%s: error %d\n", dksc->sc_xname,
453 		    obp->b_error));
454 	}
455 
456 	/* Perform the decryption if we are reading.
457 	 *
458 	 * Note: use the blocknumber from nbp, since it is what
459 	 *       we used to encrypt the blocks.
460 	 */
461 
462 	if (nbp->b_flags & B_READ)
463 		cgd_cipher(cs, obp->b_data, obp->b_data, obp->b_bcount,
464 		    nbp->b_blkno, DEV_BSIZE, CGD_CIPHER_DECRYPT);
465 
466 	/* If we allocated memory, free it now... */
467 	if (nbp->b_data != obp->b_data)
468 		cgd_putdata(dksc, nbp->b_data);
469 
470 	putiobuf(nbp);
471 
472 	/* Request is complete for whatever reason */
473 	obp->b_resid = 0;
474 	if (obp->b_error != 0)
475 		obp->b_resid = obp->b_bcount;
476 	s = splbio();
477 	disk_unbusy(&dksc->sc_dkdev, obp->b_bcount - obp->b_resid,
478 	    (obp->b_flags & B_READ));
479 	biodone(obp);
480 	dk_iodone(di, dksc);
481 	splx(s);
482 }
483 
484 /* XXX: we should probably put these into dksubr.c, mostly */
485 static int
486 cgdread(dev_t dev, struct uio *uio, int flags)
487 {
488 	struct	cgd_softc *cs;
489 	struct	dk_softc *dksc;
490 
491 	DPRINTF_FOLLOW(("cgdread(0x%llx, %p, %d)\n",
492 	    (unsigned long long)dev, uio, flags));
493 	GETCGD_SOFTC(cs, dev);
494 	dksc = &cs->sc_dksc;
495 	if ((dksc->sc_flags & DKF_INITED) == 0)
496 		return ENXIO;
497 	return physio(cgdstrategy, NULL, dev, B_READ, minphys, uio);
498 }
499 
500 /* XXX: we should probably put these into dksubr.c, mostly */
501 static int
502 cgdwrite(dev_t dev, struct uio *uio, int flags)
503 {
504 	struct	cgd_softc *cs;
505 	struct	dk_softc *dksc;
506 
507 	DPRINTF_FOLLOW(("cgdwrite(0x%"PRIx64", %p, %d)\n", dev, uio, flags));
508 	GETCGD_SOFTC(cs, dev);
509 	dksc = &cs->sc_dksc;
510 	if ((dksc->sc_flags & DKF_INITED) == 0)
511 		return ENXIO;
512 	return physio(cgdstrategy, NULL, dev, B_WRITE, minphys, uio);
513 }
514 
515 static int
516 cgdioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
517 {
518 	struct	cgd_softc *cs;
519 	struct	dk_softc *dksc;
520 	struct	disk *dk;
521 	int	part = DISKPART(dev);
522 	int	pmask = 1 << part;
523 
524 	DPRINTF_FOLLOW(("cgdioctl(0x%"PRIx64", %ld, %p, %d, %p)\n",
525 	    dev, cmd, data, flag, l));
526 	GETCGD_SOFTC(cs, dev);
527 	dksc = &cs->sc_dksc;
528 	dk = &dksc->sc_dkdev;
529 	switch (cmd) {
530 	case CGDIOCSET:
531 	case CGDIOCCLR:
532 		if ((flag & FWRITE) == 0)
533 			return EBADF;
534 	}
535 
536 	switch (cmd) {
537 	case CGDIOCSET:
538 		if (dksc->sc_flags & DKF_INITED)
539 			return EBUSY;
540 		return cgd_ioctl_set(cs, data, l);
541 	case CGDIOCCLR:
542 		if (DK_BUSY(&cs->sc_dksc, pmask))
543 			return EBUSY;
544 		return cgd_ioctl_clr(cs, l);
545 	case DIOCCACHESYNC:
546 		/*
547 		 * XXX Do we really need to care about having a writable
548 		 * file descriptor here?
549 		 */
550 		if ((flag & FWRITE) == 0)
551 			return (EBADF);
552 
553 		/*
554 		 * We pass this call down to the underlying disk.
555 		 */
556 		return VOP_IOCTL(cs->sc_tvn, cmd, data, flag, l->l_cred);
557 	default:
558 		return dk_ioctl(di, dksc, dev, cmd, data, flag, l);
559 	}
560 }
561 
562 static int
563 cgddump(dev_t dev, daddr_t blkno, void *va, size_t size)
564 {
565 	struct	cgd_softc *cs;
566 
567 	DPRINTF_FOLLOW(("cgddump(0x%"PRIx64", %" PRId64 ", %p, %lu)\n",
568 	    dev, blkno, va, (unsigned long)size));
569 	GETCGD_SOFTC(cs, dev);
570 	return dk_dump(di, &cs->sc_dksc, dev, blkno, va, size);
571 }
572 
573 /*
574  * XXXrcd:
575  *  for now we hardcode the maximum key length.
576  */
577 #define MAX_KEYSIZE	1024
578 
579 static const struct {
580 	const char *n;
581 	int v;
582 	int d;
583 } encblkno[] = {
584 	{ "encblkno",  CGD_CIPHER_CBC_ENCBLKNO8, 1 },
585 	{ "encblkno8", CGD_CIPHER_CBC_ENCBLKNO8, 1 },
586 	{ "encblkno1", CGD_CIPHER_CBC_ENCBLKNO1, 8 },
587 };
588 
589 /* ARGSUSED */
590 static int
591 cgd_ioctl_set(struct cgd_softc *cs, void *data, struct lwp *l)
592 {
593 	struct	 cgd_ioctl *ci = data;
594 	struct	 vnode *vp;
595 	int	 ret;
596 	size_t	 i;
597 	size_t	 keybytes;			/* key length in bytes */
598 	const char *cp;
599 	struct pathbuf *pb;
600 	char	 *inbuf;
601 
602 	cp = ci->ci_disk;
603 
604 	ret = pathbuf_copyin(ci->ci_disk, &pb);
605 	if (ret != 0) {
606 		return ret;
607 	}
608 	ret = dk_lookup(pb, l, &vp);
609 	pathbuf_destroy(pb);
610 	if (ret != 0) {
611 		return ret;
612 	}
613 
614 	inbuf = malloc(MAX_KEYSIZE, M_TEMP, M_WAITOK);
615 
616 	if ((ret = cgdinit(cs, cp, vp, l)) != 0)
617 		goto bail;
618 
619 	(void)memset(inbuf, 0, MAX_KEYSIZE);
620 	ret = copyinstr(ci->ci_alg, inbuf, 256, NULL);
621 	if (ret)
622 		goto bail;
623 	cs->sc_cfuncs = cryptfuncs_find(inbuf);
624 	if (!cs->sc_cfuncs) {
625 		ret = EINVAL;
626 		goto bail;
627 	}
628 
629 	(void)memset(inbuf, 0, MAX_KEYSIZE);
630 	ret = copyinstr(ci->ci_ivmethod, inbuf, MAX_KEYSIZE, NULL);
631 	if (ret)
632 		goto bail;
633 
634 	for (i = 0; i < __arraycount(encblkno); i++)
635 		if (strcmp(encblkno[i].n, inbuf) == 0)
636 			break;
637 
638 	if (i == __arraycount(encblkno)) {
639 		ret = EINVAL;
640 		goto bail;
641 	}
642 
643 	keybytes = ci->ci_keylen / 8 + 1;
644 	if (keybytes > MAX_KEYSIZE) {
645 		ret = EINVAL;
646 		goto bail;
647 	}
648 
649 	(void)memset(inbuf, 0, MAX_KEYSIZE);
650 	ret = copyin(ci->ci_key, inbuf, keybytes);
651 	if (ret)
652 		goto bail;
653 
654 	cs->sc_cdata.cf_blocksize = ci->ci_blocksize;
655 	cs->sc_cdata.cf_mode = encblkno[i].v;
656 	cs->sc_cdata.cf_priv = cs->sc_cfuncs->cf_init(ci->ci_keylen, inbuf,
657 	    &cs->sc_cdata.cf_blocksize);
658 	if (cs->sc_cdata.cf_blocksize > CGD_MAXBLOCKSIZE) {
659 	    log(LOG_WARNING, "cgd: Disallowed cipher with blocksize %zu > %u\n",
660 		cs->sc_cdata.cf_blocksize, CGD_MAXBLOCKSIZE);
661 	    cs->sc_cdata.cf_priv = NULL;
662 	}
663 
664 	/*
665 	 * The blocksize is supposed to be in bytes. Unfortunately originally
666 	 * it was expressed in bits. For compatibility we maintain encblkno
667 	 * and encblkno8.
668 	 */
669 	cs->sc_cdata.cf_blocksize /= encblkno[i].d;
670 	(void)memset(inbuf, 0, MAX_KEYSIZE);
671 	if (!cs->sc_cdata.cf_priv) {
672 		ret = EINVAL;		/* XXX is this the right error? */
673 		goto bail;
674 	}
675 	free(inbuf, M_TEMP);
676 
677 	bufq_alloc(&cs->sc_dksc.sc_bufq, "fcfs", 0);
678 
679 	cs->sc_data = malloc(MAXPHYS, M_DEVBUF, M_WAITOK);
680 	cs->sc_data_used = 0;
681 
682 	cs->sc_dksc.sc_flags |= DKF_INITED;
683 
684 	/* Attach the disk. */
685 	disk_attach(&cs->sc_dksc.sc_dkdev);
686 
687 	/* Try and read the disklabel. */
688 	dk_getdisklabel(di, &cs->sc_dksc, 0 /* XXX ? (cause of PR 41704) */);
689 
690 	/* Discover wedges on this disk. */
691 	dkwedge_discover(&cs->sc_dksc.sc_dkdev);
692 
693 	return 0;
694 
695 bail:
696 	free(inbuf, M_TEMP);
697 	(void)vn_close(vp, FREAD|FWRITE, l->l_cred);
698 	return ret;
699 }
700 
701 /* ARGSUSED */
702 static int
703 cgd_ioctl_clr(struct cgd_softc *cs, struct lwp *l)
704 {
705 	int	s;
706 	struct	dk_softc *dksc;
707 
708 	dksc = &cs->sc_dksc;
709 
710 	if ((dksc->sc_flags & DKF_INITED) == 0)
711 		return ENXIO;
712 
713 	/* Delete all of our wedges. */
714 	dkwedge_delall(&cs->sc_dksc.sc_dkdev);
715 
716 	/* Kill off any queued buffers. */
717 	s = splbio();
718 	bufq_drain(cs->sc_dksc.sc_bufq);
719 	splx(s);
720 	bufq_free(cs->sc_dksc.sc_bufq);
721 
722 	(void)vn_close(cs->sc_tvn, FREAD|FWRITE, l->l_cred);
723 	cs->sc_cfuncs->cf_destroy(cs->sc_cdata.cf_priv);
724 	free(cs->sc_tpath, M_DEVBUF);
725 	free(cs->sc_data, M_DEVBUF);
726 	cs->sc_data_used = 0;
727 	cs->sc_dksc.sc_flags &= ~DKF_INITED;
728 	disk_detach(&cs->sc_dksc.sc_dkdev);
729 
730 	return 0;
731 }
732 
733 static int
734 getsize(struct lwp *l, struct vnode *vp, size_t *size)
735 {
736 	struct partinfo dpart;
737 	struct dkwedge_info dkw;
738 	int ret;
739 
740 	if ((ret = VOP_IOCTL(vp, DIOCGWEDGEINFO, &dkw, FREAD,
741 	    l->l_cred)) == 0) {
742 		*size = dkw.dkw_size;
743 		return 0;
744 	}
745 
746 	if ((ret = VOP_IOCTL(vp, DIOCGPART, &dpart, FREAD, l->l_cred)) == 0) {
747 		*size = dpart.part->p_size;
748 		return 0;
749 	}
750 
751 	return ret;
752 }
753 
754 
755 static int
756 cgdinit(struct cgd_softc *cs, const char *cpath, struct vnode *vp,
757 	struct lwp *l)
758 {
759 	struct	dk_geom *pdg;
760 	struct	vattr va;
761 	size_t	size;
762 	int	ret;
763 	char	*tmppath;
764 
765 	cs->sc_dksc.sc_size = 0;
766 	cs->sc_tvn = vp;
767 	cs->sc_tpath = NULL;
768 
769 	tmppath = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
770 	ret = copyinstr(cpath, tmppath, MAXPATHLEN, &cs->sc_tpathlen);
771 	if (ret)
772 		goto bail;
773 	cs->sc_tpath = malloc(cs->sc_tpathlen, M_DEVBUF, M_WAITOK);
774 	memcpy(cs->sc_tpath, tmppath, cs->sc_tpathlen);
775 
776 	if ((ret = VOP_GETATTR(vp, &va, l->l_cred)) != 0)
777 		goto bail;
778 
779 	cs->sc_tdev = va.va_rdev;
780 
781 	if ((ret = getsize(l, vp, &size)) != 0)
782 		goto bail;
783 
784 	if (!size) {
785 		ret = ENODEV;
786 		goto bail;
787 	}
788 
789 	cs->sc_dksc.sc_size = size;
790 
791 	/*
792 	 * XXX here we should probe the underlying device.  If we
793 	 *     are accessing a partition of type RAW_PART, then
794 	 *     we should populate our initial geometry with the
795 	 *     geometry that we discover from the device.
796 	 */
797 	pdg = &cs->sc_dksc.sc_geom;
798 	pdg->pdg_secsize = DEV_BSIZE;
799 	pdg->pdg_ntracks = 1;
800 	pdg->pdg_nsectors = 1024 * (1024 / pdg->pdg_secsize);
801 	pdg->pdg_ncylinders = cs->sc_dksc.sc_size / pdg->pdg_nsectors;
802 
803 bail:
804 	free(tmppath, M_TEMP);
805 	if (ret && cs->sc_tpath)
806 		free(cs->sc_tpath, M_DEVBUF);
807 	return ret;
808 }
809 
810 /*
811  * Our generic cipher entry point.  This takes care of the
812  * IV mode and passes off the work to the specific cipher.
813  * We implement here the IV method ``encrypted block
814  * number''.
815  *
816  * For the encryption case, we accomplish this by setting
817  * up a struct uio where the first iovec of the source is
818  * the blocknumber and the first iovec of the dest is a
819  * sink.  We then call the cipher with an IV of zero, and
820  * the right thing happens.
821  *
822  * For the decryption case, we use the same basic mechanism
823  * for symmetry, but we encrypt the block number in the
824  * first iovec.
825  *
826  * We mainly do this to avoid requiring the definition of
827  * an ECB mode.
828  *
829  * XXXrcd: for now we rely on our own crypto framework defined
830  *         in dev/cgd_crypto.c.  This will change when we
831  *         get a generic kernel crypto framework.
832  */
833 
834 static void
835 blkno2blkno_buf(char *sbuf, daddr_t blkno)
836 {
837 	int	i;
838 
839 	/* Set up the blkno in blkno_buf, here we do not care much
840 	 * about the final layout of the information as long as we
841 	 * can guarantee that each sector will have a different IV
842 	 * and that the endianness of the machine will not affect
843 	 * the representation that we have chosen.
844 	 *
845 	 * We choose this representation, because it does not rely
846 	 * on the size of buf (which is the blocksize of the cipher),
847 	 * but allows daddr_t to grow without breaking existing
848 	 * disks.
849 	 *
850 	 * Note that blkno2blkno_buf does not take a size as input,
851 	 * and hence must be called on a pre-zeroed buffer of length
852 	 * greater than or equal to sizeof(daddr_t).
853 	 */
854 	for (i=0; i < sizeof(daddr_t); i++) {
855 		*sbuf++ = blkno & 0xff;
856 		blkno >>= 8;
857 	}
858 }
859 
860 static void
861 cgd_cipher(struct cgd_softc *cs, void *dstv, void *srcv,
862     size_t len, daddr_t blkno, size_t secsize, int dir)
863 {
864 	char		*dst = dstv;
865 	char 		*src = srcv;
866 	cfunc_cipher	*cipher = cs->sc_cfuncs->cf_cipher;
867 	struct uio	dstuio;
868 	struct uio	srcuio;
869 	struct iovec	dstiov[2];
870 	struct iovec	srciov[2];
871 	size_t		blocksize = cs->sc_cdata.cf_blocksize;
872 	char		sink[CGD_MAXBLOCKSIZE];
873 	char		zero_iv[CGD_MAXBLOCKSIZE];
874 	char		blkno_buf[CGD_MAXBLOCKSIZE];
875 
876 	DPRINTF_FOLLOW(("cgd_cipher() dir=%d\n", dir));
877 
878 	DIAGCONDPANIC(len % blocksize != 0,
879 	    ("cgd_cipher: len %% blocksize != 0"));
880 
881 	/* ensure that sizeof(daddr_t) <= blocksize (for encblkno IVing) */
882 	DIAGCONDPANIC(sizeof(daddr_t) > blocksize,
883 	    ("cgd_cipher: sizeof(daddr_t) > blocksize"));
884 
885 	memset(zero_iv, 0x0, blocksize);
886 
887 	dstuio.uio_iov = dstiov;
888 	dstuio.uio_iovcnt = 2;
889 
890 	srcuio.uio_iov = srciov;
891 	srcuio.uio_iovcnt = 2;
892 
893 	dstiov[0].iov_base = sink;
894 	dstiov[0].iov_len  = blocksize;
895 	srciov[0].iov_base = blkno_buf;
896 	srciov[0].iov_len  = blocksize;
897 	dstiov[1].iov_len  = secsize;
898 	srciov[1].iov_len  = secsize;
899 
900 	for (; len > 0; len -= secsize) {
901 		dstiov[1].iov_base = dst;
902 		srciov[1].iov_base = src;
903 
904 		memset(blkno_buf, 0x0, blocksize);
905 		blkno2blkno_buf(blkno_buf, blkno);
906 		if (dir == CGD_CIPHER_DECRYPT) {
907 			dstuio.uio_iovcnt = 1;
908 			srcuio.uio_iovcnt = 1;
909 			IFDEBUG(CGDB_CRYPTO, hexprint("step 0: blkno_buf",
910 			    blkno_buf, blocksize));
911 			cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio,
912 			    zero_iv, CGD_CIPHER_ENCRYPT);
913 			memcpy(blkno_buf, sink, blocksize);
914 			dstuio.uio_iovcnt = 2;
915 			srcuio.uio_iovcnt = 2;
916 		}
917 
918 		IFDEBUG(CGDB_CRYPTO, hexprint("step 1: blkno_buf",
919 		    blkno_buf, blocksize));
920 		cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio, zero_iv, dir);
921 		IFDEBUG(CGDB_CRYPTO, hexprint("step 2: sink",
922 		    sink, blocksize));
923 
924 		dst += secsize;
925 		src += secsize;
926 		blkno++;
927 	}
928 }
929 
930 #ifdef DEBUG
931 static void
932 hexprint(const char *start, void *buf, int len)
933 {
934 	char	*c = buf;
935 
936 	DIAGCONDPANIC(len < 0, ("hexprint: called with len < 0"));
937 	printf("%s: len=%06d 0x", start, len);
938 	while (len--)
939 		printf("%02x", (unsigned char) *c++);
940 }
941 #endif
942 
943 MODULE(MODULE_CLASS_DRIVER, cgd, NULL);
944 
945 #ifdef _MODULE
946 CFDRIVER_DECL(cgd, DV_DISK, NULL);
947 #endif
948 
949 static int
950 cgd_modcmd(modcmd_t cmd, void *arg)
951 {
952 	int bmajor, cmajor, error = 0;
953 
954 	bmajor = cmajor = -1;
955 
956 	switch (cmd) {
957 	case MODULE_CMD_INIT:
958 #ifdef _MODULE
959 		error = config_cfdriver_attach(&cgd_cd);
960 		if (error)
961 			break;
962 
963 		error = config_cfattach_attach(cgd_cd.cd_name, &cgd_ca);
964 	        if (error) {
965 			config_cfdriver_detach(&cgd_cd);
966 			aprint_error("%s: unable to register cfattach\n",
967 			    cgd_cd.cd_name);
968 			break;
969 		}
970 
971 		error = devsw_attach("cgd", &cgd_bdevsw, &bmajor,
972 		    &cgd_cdevsw, &cmajor);
973 		if (error) {
974 			config_cfattach_detach(cgd_cd.cd_name, &cgd_ca);
975 			config_cfdriver_detach(&cgd_cd);
976 			break;
977 		}
978 #endif
979 		break;
980 
981 	case MODULE_CMD_FINI:
982 #ifdef _MODULE
983 		error = config_cfattach_detach(cgd_cd.cd_name, &cgd_ca);
984 		if (error)
985 			break;
986 		config_cfdriver_detach(&cgd_cd);
987 		devsw_detach(&cgd_bdevsw, &cgd_cdevsw);
988 #endif
989 		break;
990 
991 	case MODULE_CMD_STAT:
992 		return ENOTTY;
993 
994 	default:
995 		return ENOTTY;
996 	}
997 
998 	return error;
999 }
1000