xref: /netbsd-src/sys/dev/cgd.c (revision daf6c4152fcddc27c445489775ed1f66ab4ea9a9)
1 /* $NetBSD: cgd.c,v 1.71 2010/11/19 06:44:39 dholland 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 1.71 2010/11/19 06:44:39 dholland 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/pool.h>
44 #include <sys/ioctl.h>
45 #include <sys/device.h>
46 #include <sys/disk.h>
47 #include <sys/disklabel.h>
48 #include <sys/fcntl.h>
49 #include <sys/namei.h> /* for pathbuf */
50 #include <sys/vnode.h>
51 #include <sys/conf.h>
52 #include <sys/syslog.h>
53 
54 #include <dev/dkvar.h>
55 #include <dev/cgdvar.h>
56 
57 /* Entry Point Functions */
58 
59 void	cgdattach(int);
60 
61 static dev_type_open(cgdopen);
62 static dev_type_close(cgdclose);
63 static dev_type_read(cgdread);
64 static dev_type_write(cgdwrite);
65 static dev_type_ioctl(cgdioctl);
66 static dev_type_strategy(cgdstrategy);
67 static dev_type_dump(cgddump);
68 static dev_type_size(cgdsize);
69 
70 const struct bdevsw cgd_bdevsw = {
71 	cgdopen, cgdclose, cgdstrategy, cgdioctl,
72 	cgddump, cgdsize, D_DISK
73 };
74 
75 const struct cdevsw cgd_cdevsw = {
76 	cgdopen, cgdclose, cgdread, cgdwrite, cgdioctl,
77 	nostop, notty, nopoll, nommap, nokqfilter, D_DISK
78 };
79 
80 static int cgd_match(device_t, cfdata_t, void *);
81 static void cgd_attach(device_t, device_t, void *);
82 static int cgd_detach(device_t, int);
83 static struct cgd_softc	*cgd_spawn(int);
84 static int cgd_destroy(device_t);
85 
86 /* Internal Functions */
87 
88 static int	cgdstart(struct dk_softc *, struct buf *);
89 static void	cgdiodone(struct buf *);
90 
91 static int	cgd_ioctl_set(struct cgd_softc *, void *, struct lwp *);
92 static int	cgd_ioctl_clr(struct cgd_softc *, struct lwp *);
93 static int	cgdinit(struct cgd_softc *, const char *, struct vnode *,
94 			struct lwp *);
95 static void	cgd_cipher(struct cgd_softc *, void *, void *,
96 			   size_t, daddr_t, size_t, int);
97 
98 /* Pseudo-disk Interface */
99 
100 static struct dk_intf the_dkintf = {
101 	DTYPE_CGD,
102 	"cgd",
103 	cgdopen,
104 	cgdclose,
105 	cgdstrategy,
106 	cgdstart,
107 };
108 static struct dk_intf *di = &the_dkintf;
109 
110 static struct dkdriver cgddkdriver = {
111 	.d_strategy = cgdstrategy,
112 	.d_minphys = minphys,
113 };
114 
115 CFATTACH_DECL3_NEW(cgd, sizeof(struct cgd_softc),
116     cgd_match, cgd_attach, cgd_detach, NULL, NULL, NULL, DVF_DETACH_SHUTDOWN);
117 extern struct cfdriver cgd_cd;
118 
119 /* DIAGNOSTIC and DEBUG definitions */
120 
121 #if defined(CGDDEBUG) && !defined(DEBUG)
122 #define DEBUG
123 #endif
124 
125 #ifdef DEBUG
126 int cgddebug = 0;
127 
128 #define CGDB_FOLLOW	0x1
129 #define CGDB_IO	0x2
130 #define CGDB_CRYPTO	0x4
131 
132 #define IFDEBUG(x,y)		if (cgddebug & (x)) y
133 #define DPRINTF(x,y)		IFDEBUG(x, printf y)
134 #define DPRINTF_FOLLOW(y)	DPRINTF(CGDB_FOLLOW, y)
135 
136 static void	hexprint(const char *, void *, int);
137 
138 #else
139 #define IFDEBUG(x,y)
140 #define DPRINTF(x,y)
141 #define DPRINTF_FOLLOW(y)
142 #endif
143 
144 #ifdef DIAGNOSTIC
145 #define DIAGPANIC(x)		panic x
146 #define DIAGCONDPANIC(x,y)	if (x) panic y
147 #else
148 #define DIAGPANIC(x)
149 #define DIAGCONDPANIC(x,y)
150 #endif
151 
152 /* Global variables */
153 
154 /* Utility Functions */
155 
156 #define CGDUNIT(x)		DISKUNIT(x)
157 #define GETCGD_SOFTC(_cs, x)	if (!((_cs) = getcgd_softc(x))) return ENXIO
158 
159 /* The code */
160 
161 static struct cgd_softc *
162 getcgd_softc(dev_t dev)
163 {
164 	int	unit = CGDUNIT(dev);
165 	struct cgd_softc *sc;
166 
167 	DPRINTF_FOLLOW(("getcgd_softc(0x%"PRIx64"): unit = %d\n", dev, unit));
168 
169 	sc = device_lookup_private(&cgd_cd, unit);
170 	if (sc == NULL)
171 		sc = cgd_spawn(unit);
172 	return sc;
173 }
174 
175 static int
176 cgd_match(device_t self, cfdata_t cfdata, void *aux)
177 {
178 
179 	return 1;
180 }
181 
182 static void
183 cgd_attach(device_t parent, device_t self, void *aux)
184 {
185 	struct cgd_softc *sc = device_private(self);
186 
187 	sc->sc_dev = self;
188 	simple_lock_init(&sc->sc_slock);
189 	dk_sc_init(&sc->sc_dksc, sc, device_xname(sc->sc_dev));
190 	disk_init(&sc->sc_dksc.sc_dkdev, sc->sc_dksc.sc_xname, &cgddkdriver);
191 
192 	 if (!pmf_device_register(self, NULL, NULL))
193 		aprint_error_dev(self, "unable to register power management hooks\n");
194 }
195 
196 
197 static int
198 cgd_detach(device_t self, int flags)
199 {
200 	int ret;
201 	const int pmask = 1 << RAW_PART;
202 	struct cgd_softc *sc = device_private(self);
203 	struct dk_softc *dksc = &sc->sc_dksc;
204 
205 	if (DK_BUSY(dksc, pmask))
206 		return EBUSY;
207 
208 	if ((dksc->sc_flags & DKF_INITED) != 0 &&
209 	    (ret = cgd_ioctl_clr(sc, curlwp)) != 0)
210 		return ret;
211 
212 	disk_destroy(&dksc->sc_dkdev);
213 
214 	return 0;
215 }
216 
217 void
218 cgdattach(int num)
219 {
220 	int error;
221 
222 	error = config_cfattach_attach(cgd_cd.cd_name, &cgd_ca);
223 	if (error != 0)
224 		aprint_error("%s: unable to register cfattach\n",
225 		    cgd_cd.cd_name);
226 }
227 
228 static struct cgd_softc *
229 cgd_spawn(int unit)
230 {
231 	cfdata_t cf;
232 
233 	cf = malloc(sizeof(*cf), M_DEVBUF, M_WAITOK);
234 	cf->cf_name = cgd_cd.cd_name;
235 	cf->cf_atname = cgd_cd.cd_name;
236 	cf->cf_unit = unit;
237 	cf->cf_fstate = FSTATE_STAR;
238 
239 	return device_private(config_attach_pseudo(cf));
240 }
241 
242 static int
243 cgd_destroy(device_t dev)
244 {
245 	int error;
246 	cfdata_t cf;
247 
248 	cf = device_cfdata(dev);
249 	error = config_detach(dev, DETACH_QUIET);
250 	if (error)
251 		return error;
252 	free(cf, M_DEVBUF);
253 	return 0;
254 }
255 
256 static int
257 cgdopen(dev_t dev, int flags, int fmt, struct lwp *l)
258 {
259 	struct	cgd_softc *cs;
260 
261 	DPRINTF_FOLLOW(("cgdopen(0x%"PRIx64", %d)\n", dev, flags));
262 	GETCGD_SOFTC(cs, dev);
263 	return dk_open(di, &cs->sc_dksc, dev, flags, fmt, l);
264 }
265 
266 static int
267 cgdclose(dev_t dev, int flags, int fmt, struct lwp *l)
268 {
269 	int error;
270 	struct	cgd_softc *cs;
271 	struct	dk_softc *dksc;
272 
273 	DPRINTF_FOLLOW(("cgdclose(0x%"PRIx64", %d)\n", dev, flags));
274 	GETCGD_SOFTC(cs, dev);
275 	dksc = &cs->sc_dksc;
276 	if ((error =  dk_close(di, dksc, dev, flags, fmt, l)) != 0)
277 		return error;
278 
279 	if ((dksc->sc_flags & DKF_INITED) == 0) {
280 		if ((error = cgd_destroy(cs->sc_dev)) != 0) {
281 			aprint_error_dev(cs->sc_dev,
282 			    "unable to detach instance\n");
283 			return error;
284 		}
285 	}
286 	return 0;
287 }
288 
289 static void
290 cgdstrategy(struct buf *bp)
291 {
292 	struct	cgd_softc *cs = getcgd_softc(bp->b_dev);
293 
294 	DPRINTF_FOLLOW(("cgdstrategy(%p): b_bcount = %ld\n", bp,
295 	    (long)bp->b_bcount));
296 	/* XXXrcd: Should we test for (cs != NULL)? */
297 	dk_strategy(di, &cs->sc_dksc, bp);
298 	return;
299 }
300 
301 static int
302 cgdsize(dev_t dev)
303 {
304 	struct cgd_softc *cs = getcgd_softc(dev);
305 
306 	DPRINTF_FOLLOW(("cgdsize(0x%"PRIx64")\n", dev));
307 	if (!cs)
308 		return -1;
309 	return dk_size(di, &cs->sc_dksc, dev);
310 }
311 
312 /*
313  * cgd_{get,put}data are functions that deal with getting a buffer
314  * for the new encrypted data.  We have a buffer per device so that
315  * we can ensure that we can always have a transaction in flight.
316  * We use this buffer first so that we have one less piece of
317  * malloc'ed data at any given point.
318  */
319 
320 static void *
321 cgd_getdata(struct dk_softc *dksc, unsigned long size)
322 {
323 	struct	cgd_softc *cs =dksc->sc_osc;
324 	void *	data = NULL;
325 
326 	simple_lock(&cs->sc_slock);
327 	if (cs->sc_data_used == 0) {
328 		cs->sc_data_used = 1;
329 		data = cs->sc_data;
330 	}
331 	simple_unlock(&cs->sc_slock);
332 
333 	if (data)
334 		return data;
335 
336 	return malloc(size, M_DEVBUF, M_NOWAIT);
337 }
338 
339 static void
340 cgd_putdata(struct dk_softc *dksc, void *data)
341 {
342 	struct	cgd_softc *cs =dksc->sc_osc;
343 
344 	if (data == cs->sc_data) {
345 		simple_lock(&cs->sc_slock);
346 		cs->sc_data_used = 0;
347 		simple_unlock(&cs->sc_slock);
348 	} else {
349 		free(data, M_DEVBUF);
350 	}
351 }
352 
353 static int
354 cgdstart(struct dk_softc *dksc, struct buf *bp)
355 {
356 	struct	cgd_softc *cs = dksc->sc_osc;
357 	struct	buf *nbp;
358 	void *	addr;
359 	void *	newaddr;
360 	daddr_t	bn;
361 	struct	vnode *vp;
362 
363 	DPRINTF_FOLLOW(("cgdstart(%p, %p)\n", dksc, bp));
364 	disk_busy(&dksc->sc_dkdev); /* XXX: put in dksubr.c */
365 
366 	bn = bp->b_rawblkno;
367 
368 	/*
369 	 * We attempt to allocate all of our resources up front, so that
370 	 * we can fail quickly if they are unavailable.
371 	 */
372 
373 	nbp = getiobuf(cs->sc_tvn, false);
374 	if (nbp == NULL) {
375 		disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
376 		return -1;
377 	}
378 
379 	/*
380 	 * If we are writing, then we need to encrypt the outgoing
381 	 * block into a new block of memory.  If we fail, then we
382 	 * return an error and let the dksubr framework deal with it.
383 	 */
384 	newaddr = addr = bp->b_data;
385 	if ((bp->b_flags & B_READ) == 0) {
386 		newaddr = cgd_getdata(dksc, bp->b_bcount);
387 		if (!newaddr) {
388 			putiobuf(nbp);
389 			disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
390 			return -1;
391 		}
392 		cgd_cipher(cs, newaddr, addr, bp->b_bcount, bn,
393 		    DEV_BSIZE, CGD_CIPHER_ENCRYPT);
394 	}
395 
396 	nbp->b_data = newaddr;
397 	nbp->b_flags = bp->b_flags;
398 	nbp->b_oflags = bp->b_oflags;
399 	nbp->b_cflags = bp->b_cflags;
400 	nbp->b_iodone = cgdiodone;
401 	nbp->b_proc = bp->b_proc;
402 	nbp->b_blkno = bn;
403 	nbp->b_bcount = bp->b_bcount;
404 	nbp->b_private = bp;
405 
406 	BIO_COPYPRIO(nbp, bp);
407 
408 	if ((nbp->b_flags & B_READ) == 0) {
409 		vp = nbp->b_vp;
410 		mutex_enter(&vp->v_interlock);
411 		vp->v_numoutput++;
412 		mutex_exit(&vp->v_interlock);
413 	}
414 	VOP_STRATEGY(cs->sc_tvn, nbp);
415 	return 0;
416 }
417 
418 static void
419 cgdiodone(struct buf *nbp)
420 {
421 	struct	buf *obp = nbp->b_private;
422 	struct	cgd_softc *cs = getcgd_softc(obp->b_dev);
423 	struct	dk_softc *dksc = &cs->sc_dksc;
424 	int s;
425 
426 	KDASSERT(cs);
427 
428 	DPRINTF_FOLLOW(("cgdiodone(%p)\n", nbp));
429 	DPRINTF(CGDB_IO, ("cgdiodone: bp %p bcount %d resid %d\n",
430 	    obp, obp->b_bcount, obp->b_resid));
431 	DPRINTF(CGDB_IO, (" dev 0x%"PRIx64", nbp %p bn %" PRId64 " addr %p bcnt %d\n",
432 	    nbp->b_dev, nbp, nbp->b_blkno, nbp->b_data,
433 	    nbp->b_bcount));
434 	if (nbp->b_error != 0) {
435 		obp->b_error = nbp->b_error;
436 		DPRINTF(CGDB_IO, ("%s: error %d\n", dksc->sc_xname,
437 		    obp->b_error));
438 	}
439 
440 	/* Perform the decryption if we are reading.
441 	 *
442 	 * Note: use the blocknumber from nbp, since it is what
443 	 *       we used to encrypt the blocks.
444 	 */
445 
446 	if (nbp->b_flags & B_READ)
447 		cgd_cipher(cs, obp->b_data, obp->b_data, obp->b_bcount,
448 		    nbp->b_blkno, DEV_BSIZE, CGD_CIPHER_DECRYPT);
449 
450 	/* If we allocated memory, free it now... */
451 	if (nbp->b_data != obp->b_data)
452 		cgd_putdata(dksc, nbp->b_data);
453 
454 	putiobuf(nbp);
455 
456 	/* Request is complete for whatever reason */
457 	obp->b_resid = 0;
458 	if (obp->b_error != 0)
459 		obp->b_resid = obp->b_bcount;
460 	s = splbio();
461 	disk_unbusy(&dksc->sc_dkdev, obp->b_bcount - obp->b_resid,
462 	    (obp->b_flags & B_READ));
463 	biodone(obp);
464 	dk_iodone(di, dksc);
465 	splx(s);
466 }
467 
468 /* XXX: we should probably put these into dksubr.c, mostly */
469 static int
470 cgdread(dev_t dev, struct uio *uio, int flags)
471 {
472 	struct	cgd_softc *cs;
473 	struct	dk_softc *dksc;
474 
475 	DPRINTF_FOLLOW(("cgdread(0x%llx, %p, %d)\n",
476 	    (unsigned long long)dev, uio, flags));
477 	GETCGD_SOFTC(cs, dev);
478 	dksc = &cs->sc_dksc;
479 	if ((dksc->sc_flags & DKF_INITED) == 0)
480 		return ENXIO;
481 	return physio(cgdstrategy, NULL, dev, B_READ, minphys, uio);
482 }
483 
484 /* XXX: we should probably put these into dksubr.c, mostly */
485 static int
486 cgdwrite(dev_t dev, struct uio *uio, int flags)
487 {
488 	struct	cgd_softc *cs;
489 	struct	dk_softc *dksc;
490 
491 	DPRINTF_FOLLOW(("cgdwrite(0x%"PRIx64", %p, %d)\n", dev, uio, flags));
492 	GETCGD_SOFTC(cs, dev);
493 	dksc = &cs->sc_dksc;
494 	if ((dksc->sc_flags & DKF_INITED) == 0)
495 		return ENXIO;
496 	return physio(cgdstrategy, NULL, dev, B_WRITE, minphys, uio);
497 }
498 
499 static int
500 cgdioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
501 {
502 	struct	cgd_softc *cs;
503 	struct	dk_softc *dksc;
504 	struct	disk *dk;
505 	int	part = DISKPART(dev);
506 	int	pmask = 1 << part;
507 
508 	DPRINTF_FOLLOW(("cgdioctl(0x%"PRIx64", %ld, %p, %d, %p)\n",
509 	    dev, cmd, data, flag, l));
510 	GETCGD_SOFTC(cs, dev);
511 	dksc = &cs->sc_dksc;
512 	dk = &dksc->sc_dkdev;
513 	switch (cmd) {
514 	case CGDIOCSET:
515 	case CGDIOCCLR:
516 		if ((flag & FWRITE) == 0)
517 			return EBADF;
518 	}
519 
520 	switch (cmd) {
521 	case CGDIOCSET:
522 		if (dksc->sc_flags & DKF_INITED)
523 			return EBUSY;
524 		return cgd_ioctl_set(cs, data, l);
525 	case CGDIOCCLR:
526 		if (DK_BUSY(&cs->sc_dksc, pmask))
527 			return EBUSY;
528 		return cgd_ioctl_clr(cs, l);
529 	case DIOCCACHESYNC:
530 		/*
531 		 * XXX Do we really need to care about having a writable
532 		 * file descriptor here?
533 		 */
534 		if ((flag & FWRITE) == 0)
535 			return (EBADF);
536 
537 		/*
538 		 * We pass this call down to the underlying disk.
539 		 */
540 		return VOP_IOCTL(cs->sc_tvn, cmd, data, flag, l->l_cred);
541 	default:
542 		return dk_ioctl(di, dksc, dev, cmd, data, flag, l);
543 	}
544 }
545 
546 static int
547 cgddump(dev_t dev, daddr_t blkno, void *va, size_t size)
548 {
549 	struct	cgd_softc *cs;
550 
551 	DPRINTF_FOLLOW(("cgddump(0x%"PRIx64", %" PRId64 ", %p, %lu)\n",
552 	    dev, blkno, va, (unsigned long)size));
553 	GETCGD_SOFTC(cs, dev);
554 	return dk_dump(di, &cs->sc_dksc, dev, blkno, va, size);
555 }
556 
557 /*
558  * XXXrcd:
559  *  for now we hardcode the maximum key length.
560  */
561 #define MAX_KEYSIZE	1024
562 
563 static const struct {
564 	const char *n;
565 	int v;
566 	int d;
567 } encblkno[] = {
568 	{ "encblkno",  CGD_CIPHER_CBC_ENCBLKNO8, 1 },
569 	{ "encblkno8", CGD_CIPHER_CBC_ENCBLKNO8, 1 },
570 	{ "encblkno1", CGD_CIPHER_CBC_ENCBLKNO1, 8 },
571 };
572 
573 /* ARGSUSED */
574 static int
575 cgd_ioctl_set(struct cgd_softc *cs, void *data, struct lwp *l)
576 {
577 	struct	 cgd_ioctl *ci = data;
578 	struct	 vnode *vp;
579 	int	 ret;
580 	size_t	 i;
581 	size_t	 keybytes;			/* key length in bytes */
582 	const char *cp;
583 	struct pathbuf *pb;
584 	char	 *inbuf;
585 
586 	cp = ci->ci_disk;
587 
588 	ret = pathbuf_copyin(ci->ci_disk, &pb);
589 	if (ret != 0) {
590 		return ret;
591 	}
592 	ret = dk_lookup(pb, l, &vp);
593 	pathbuf_destroy(pb);
594 	if (ret != 0) {
595 		return ret;
596 	}
597 
598 	inbuf = malloc(MAX_KEYSIZE, M_TEMP, M_WAITOK);
599 
600 	if ((ret = cgdinit(cs, cp, vp, l)) != 0)
601 		goto bail;
602 
603 	(void)memset(inbuf, 0, MAX_KEYSIZE);
604 	ret = copyinstr(ci->ci_alg, inbuf, 256, NULL);
605 	if (ret)
606 		goto bail;
607 	cs->sc_cfuncs = cryptfuncs_find(inbuf);
608 	if (!cs->sc_cfuncs) {
609 		ret = EINVAL;
610 		goto bail;
611 	}
612 
613 	(void)memset(inbuf, 0, MAX_KEYSIZE);
614 	ret = copyinstr(ci->ci_ivmethod, inbuf, MAX_KEYSIZE, NULL);
615 	if (ret)
616 		goto bail;
617 
618 	for (i = 0; i < __arraycount(encblkno); i++)
619 		if (strcmp(encblkno[i].n, inbuf) == 0)
620 			break;
621 
622 	if (i == __arraycount(encblkno)) {
623 		ret = EINVAL;
624 		goto bail;
625 	}
626 
627 	keybytes = ci->ci_keylen / 8 + 1;
628 	if (keybytes > MAX_KEYSIZE) {
629 		ret = EINVAL;
630 		goto bail;
631 	}
632 
633 	(void)memset(inbuf, 0, MAX_KEYSIZE);
634 	ret = copyin(ci->ci_key, inbuf, keybytes);
635 	if (ret)
636 		goto bail;
637 
638 	cs->sc_cdata.cf_blocksize = ci->ci_blocksize;
639 	cs->sc_cdata.cf_mode = encblkno[i].v;
640 	cs->sc_cdata.cf_priv = cs->sc_cfuncs->cf_init(ci->ci_keylen, inbuf,
641 	    &cs->sc_cdata.cf_blocksize);
642 	if (cs->sc_cdata.cf_blocksize > CGD_MAXBLOCKSIZE) {
643 	    log(LOG_WARNING, "cgd: Disallowed cipher with blocksize %zu > %u\n",
644 		cs->sc_cdata.cf_blocksize, CGD_MAXBLOCKSIZE);
645 	    cs->sc_cdata.cf_priv = NULL;
646 	}
647 
648 	/*
649 	 * The blocksize is supposed to be in bytes. Unfortunately originally
650 	 * it was expressed in bits. For compatibility we maintain encblkno
651 	 * and encblkno8.
652 	 */
653 	cs->sc_cdata.cf_blocksize /= encblkno[i].d;
654 	(void)memset(inbuf, 0, MAX_KEYSIZE);
655 	if (!cs->sc_cdata.cf_priv) {
656 		ret = EINVAL;		/* XXX is this the right error? */
657 		goto bail;
658 	}
659 	free(inbuf, M_TEMP);
660 
661 	bufq_alloc(&cs->sc_dksc.sc_bufq, "fcfs", 0);
662 
663 	cs->sc_data = malloc(MAXPHYS, M_DEVBUF, M_WAITOK);
664 	cs->sc_data_used = 0;
665 
666 	cs->sc_dksc.sc_flags |= DKF_INITED;
667 
668 	/* Attach the disk. */
669 	disk_attach(&cs->sc_dksc.sc_dkdev);
670 
671 	/* Try and read the disklabel. */
672 	dk_getdisklabel(di, &cs->sc_dksc, 0 /* XXX ? (cause of PR 41704) */);
673 
674 	/* Discover wedges on this disk. */
675 	dkwedge_discover(&cs->sc_dksc.sc_dkdev);
676 
677 	return 0;
678 
679 bail:
680 	free(inbuf, M_TEMP);
681 	(void)vn_close(vp, FREAD|FWRITE, l->l_cred);
682 	return ret;
683 }
684 
685 /* ARGSUSED */
686 static int
687 cgd_ioctl_clr(struct cgd_softc *cs, struct lwp *l)
688 {
689 	int	s;
690 	struct	dk_softc *dksc;
691 
692 	dksc = &cs->sc_dksc;
693 
694 	if ((dksc->sc_flags & DKF_INITED) == 0)
695 		return ENXIO;
696 
697 	/* Delete all of our wedges. */
698 	dkwedge_delall(&cs->sc_dksc.sc_dkdev);
699 
700 	/* Kill off any queued buffers. */
701 	s = splbio();
702 	bufq_drain(cs->sc_dksc.sc_bufq);
703 	splx(s);
704 	bufq_free(cs->sc_dksc.sc_bufq);
705 
706 	(void)vn_close(cs->sc_tvn, FREAD|FWRITE, l->l_cred);
707 	cs->sc_cfuncs->cf_destroy(cs->sc_cdata.cf_priv);
708 	free(cs->sc_tpath, M_DEVBUF);
709 	free(cs->sc_data, M_DEVBUF);
710 	cs->sc_data_used = 0;
711 	cs->sc_dksc.sc_flags &= ~DKF_INITED;
712 	disk_detach(&cs->sc_dksc.sc_dkdev);
713 
714 	return 0;
715 }
716 
717 static int
718 getsize(struct lwp *l, struct vnode *vp, size_t *size)
719 {
720 	struct partinfo dpart;
721 	struct dkwedge_info dkw;
722 	int ret;
723 
724 	if ((ret = VOP_IOCTL(vp, DIOCGWEDGEINFO, &dkw, FREAD,
725 	    l->l_cred)) == 0) {
726 		*size = dkw.dkw_size;
727 		return 0;
728 	}
729 
730 	if ((ret = VOP_IOCTL(vp, DIOCGPART, &dpart, FREAD, l->l_cred)) == 0) {
731 		*size = dpart.part->p_size;
732 		return 0;
733 	}
734 
735 	return ret;
736 }
737 
738 
739 static int
740 cgdinit(struct cgd_softc *cs, const char *cpath, struct vnode *vp,
741 	struct lwp *l)
742 {
743 	struct	dk_geom *pdg;
744 	struct	vattr va;
745 	size_t	size;
746 	int	ret;
747 	char	*tmppath;
748 
749 	cs->sc_dksc.sc_size = 0;
750 	cs->sc_tvn = vp;
751 	cs->sc_tpath = NULL;
752 
753 	tmppath = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
754 	ret = copyinstr(cpath, tmppath, MAXPATHLEN, &cs->sc_tpathlen);
755 	if (ret)
756 		goto bail;
757 	cs->sc_tpath = malloc(cs->sc_tpathlen, M_DEVBUF, M_WAITOK);
758 	memcpy(cs->sc_tpath, tmppath, cs->sc_tpathlen);
759 
760 	if ((ret = VOP_GETATTR(vp, &va, l->l_cred)) != 0)
761 		goto bail;
762 
763 	cs->sc_tdev = va.va_rdev;
764 
765 	if ((ret = getsize(l, vp, &size)) != 0)
766 		goto bail;
767 
768 	if (!size) {
769 		ret = ENODEV;
770 		goto bail;
771 	}
772 
773 	cs->sc_dksc.sc_size = size;
774 
775 	/*
776 	 * XXX here we should probe the underlying device.  If we
777 	 *     are accessing a partition of type RAW_PART, then
778 	 *     we should populate our initial geometry with the
779 	 *     geometry that we discover from the device.
780 	 */
781 	pdg = &cs->sc_dksc.sc_geom;
782 	pdg->pdg_secsize = DEV_BSIZE;
783 	pdg->pdg_ntracks = 1;
784 	pdg->pdg_nsectors = 1024 * (1024 / pdg->pdg_secsize);
785 	pdg->pdg_ncylinders = cs->sc_dksc.sc_size / pdg->pdg_nsectors;
786 
787 bail:
788 	free(tmppath, M_TEMP);
789 	if (ret && cs->sc_tpath)
790 		free(cs->sc_tpath, M_DEVBUF);
791 	return ret;
792 }
793 
794 /*
795  * Our generic cipher entry point.  This takes care of the
796  * IV mode and passes off the work to the specific cipher.
797  * We implement here the IV method ``encrypted block
798  * number''.
799  *
800  * For the encryption case, we accomplish this by setting
801  * up a struct uio where the first iovec of the source is
802  * the blocknumber and the first iovec of the dest is a
803  * sink.  We then call the cipher with an IV of zero, and
804  * the right thing happens.
805  *
806  * For the decryption case, we use the same basic mechanism
807  * for symmetry, but we encrypt the block number in the
808  * first iovec.
809  *
810  * We mainly do this to avoid requiring the definition of
811  * an ECB mode.
812  *
813  * XXXrcd: for now we rely on our own crypto framework defined
814  *         in dev/cgd_crypto.c.  This will change when we
815  *         get a generic kernel crypto framework.
816  */
817 
818 static void
819 blkno2blkno_buf(char *sbuf, daddr_t blkno)
820 {
821 	int	i;
822 
823 	/* Set up the blkno in blkno_buf, here we do not care much
824 	 * about the final layout of the information as long as we
825 	 * can guarantee that each sector will have a different IV
826 	 * and that the endianness of the machine will not affect
827 	 * the representation that we have chosen.
828 	 *
829 	 * We choose this representation, because it does not rely
830 	 * on the size of buf (which is the blocksize of the cipher),
831 	 * but allows daddr_t to grow without breaking existing
832 	 * disks.
833 	 *
834 	 * Note that blkno2blkno_buf does not take a size as input,
835 	 * and hence must be called on a pre-zeroed buffer of length
836 	 * greater than or equal to sizeof(daddr_t).
837 	 */
838 	for (i=0; i < sizeof(daddr_t); i++) {
839 		*sbuf++ = blkno & 0xff;
840 		blkno >>= 8;
841 	}
842 }
843 
844 static void
845 cgd_cipher(struct cgd_softc *cs, void *dstv, void *srcv,
846     size_t len, daddr_t blkno, size_t secsize, int dir)
847 {
848 	char		*dst = dstv;
849 	char 		*src = srcv;
850 	cfunc_cipher	*cipher = cs->sc_cfuncs->cf_cipher;
851 	struct uio	dstuio;
852 	struct uio	srcuio;
853 	struct iovec	dstiov[2];
854 	struct iovec	srciov[2];
855 	size_t		blocksize = cs->sc_cdata.cf_blocksize;
856 	char		sink[CGD_MAXBLOCKSIZE];
857 	char		zero_iv[CGD_MAXBLOCKSIZE];
858 	char		blkno_buf[CGD_MAXBLOCKSIZE];
859 
860 	DPRINTF_FOLLOW(("cgd_cipher() dir=%d\n", dir));
861 
862 	DIAGCONDPANIC(len % blocksize != 0,
863 	    ("cgd_cipher: len %% blocksize != 0"));
864 
865 	/* ensure that sizeof(daddr_t) <= blocksize (for encblkno IVing) */
866 	DIAGCONDPANIC(sizeof(daddr_t) > blocksize,
867 	    ("cgd_cipher: sizeof(daddr_t) > blocksize"));
868 
869 	memset(zero_iv, 0x0, blocksize);
870 
871 	dstuio.uio_iov = dstiov;
872 	dstuio.uio_iovcnt = 2;
873 
874 	srcuio.uio_iov = srciov;
875 	srcuio.uio_iovcnt = 2;
876 
877 	dstiov[0].iov_base = sink;
878 	dstiov[0].iov_len  = blocksize;
879 	srciov[0].iov_base = blkno_buf;
880 	srciov[0].iov_len  = blocksize;
881 	dstiov[1].iov_len  = secsize;
882 	srciov[1].iov_len  = secsize;
883 
884 	for (; len > 0; len -= secsize) {
885 		dstiov[1].iov_base = dst;
886 		srciov[1].iov_base = src;
887 
888 		memset(blkno_buf, 0x0, blocksize);
889 		blkno2blkno_buf(blkno_buf, blkno);
890 		if (dir == CGD_CIPHER_DECRYPT) {
891 			dstuio.uio_iovcnt = 1;
892 			srcuio.uio_iovcnt = 1;
893 			IFDEBUG(CGDB_CRYPTO, hexprint("step 0: blkno_buf",
894 			    blkno_buf, blocksize));
895 			cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio,
896 			    zero_iv, CGD_CIPHER_ENCRYPT);
897 			memcpy(blkno_buf, sink, blocksize);
898 			dstuio.uio_iovcnt = 2;
899 			srcuio.uio_iovcnt = 2;
900 		}
901 
902 		IFDEBUG(CGDB_CRYPTO, hexprint("step 1: blkno_buf",
903 		    blkno_buf, blocksize));
904 		cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio, zero_iv, dir);
905 		IFDEBUG(CGDB_CRYPTO, hexprint("step 2: sink",
906 		    sink, blocksize));
907 
908 		dst += secsize;
909 		src += secsize;
910 		blkno++;
911 	}
912 }
913 
914 #ifdef DEBUG
915 static void
916 hexprint(const char *start, void *buf, int len)
917 {
918 	char	*c = buf;
919 
920 	DIAGCONDPANIC(len < 0, ("hexprint: called with len < 0"));
921 	printf("%s: len=%06d 0x", start, len);
922 	while (len--)
923 		printf("%02x", (unsigned char) *c++);
924 }
925 #endif
926 
927 #ifdef _MODULE
928 
929 #include <sys/module.h>
930 
931 MODULE(MODULE_CLASS_DRIVER, cgd, NULL);
932 CFDRIVER_DECL(cgd, DV_DISK, NULL);
933 
934 static int
935 cgd_modcmd(modcmd_t cmd, void *arg)
936 {
937 	int bmajor = -1, cmajor = -1,  error = 0;
938 
939 	switch (cmd) {
940 	case MODULE_CMD_INIT:
941 		error = config_cfdriver_attach(&cgd_cd);
942 		if (error)
943 			break;
944 
945 		error = config_cfattach_attach(cgd_cd.cd_name, &cgd_ca);
946 	        if (error) {
947 			config_cfdriver_detach(&cgd_cd);
948 			aprint_error("%s: unable to register cfattach\n",
949 			    cgd_cd.cd_name);
950 			break;
951 		}
952 
953 		error = devsw_attach("cgd", &cgd_bdevsw, &bmajor,
954 		    &cgd_cdevsw, &cmajor);
955 		if (error) {
956 			config_cfattach_detach(cgd_cd.cd_name, &cgd_ca);
957 			config_cfdriver_detach(&cgd_cd);
958 			break;
959 		}
960 
961 		break;
962 
963 	case MODULE_CMD_FINI:
964 		error = config_cfattach_detach(cgd_cd.cd_name, &cgd_ca);
965 		if (error)
966 			break;
967 		config_cfdriver_detach(&cgd_cd);
968 		devsw_detach(&cgd_bdevsw, &cgd_cdevsw);
969 		break;
970 
971 	case MODULE_CMD_STAT:
972 		return ENOTTY;
973 
974 	default:
975 		return ENOTTY;
976 	}
977 
978 	return error;
979 }
980 
981 #endif
982