xref: /netbsd-src/sys/dev/cgd.c (revision 6cf6fe02a981b55727c49c3d37b0d8191a98c0ee)
1 /* $NetBSD: cgd.c,v 1.90 2014/07/25 08:10:35 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 1.90 2014/07/25 08:10:35 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/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 #include <miscfs/specfs/specdev.h> /* for v_rdev */
59 
60 /* Entry Point Functions */
61 
62 void	cgdattach(int);
63 
64 static dev_type_open(cgdopen);
65 static dev_type_close(cgdclose);
66 static dev_type_read(cgdread);
67 static dev_type_write(cgdwrite);
68 static dev_type_ioctl(cgdioctl);
69 static dev_type_strategy(cgdstrategy);
70 static dev_type_dump(cgddump);
71 static dev_type_size(cgdsize);
72 
73 const struct bdevsw cgd_bdevsw = {
74 	.d_open = cgdopen,
75 	.d_close = cgdclose,
76 	.d_strategy = cgdstrategy,
77 	.d_ioctl = cgdioctl,
78 	.d_dump = cgddump,
79 	.d_psize = cgdsize,
80 	.d_discard = nodiscard,
81 	.d_flag = D_DISK
82 };
83 
84 const struct cdevsw cgd_cdevsw = {
85 	.d_open = cgdopen,
86 	.d_close = cgdclose,
87 	.d_read = cgdread,
88 	.d_write = cgdwrite,
89 	.d_ioctl = cgdioctl,
90 	.d_stop = nostop,
91 	.d_tty = notty,
92 	.d_poll = nopoll,
93 	.d_mmap = nommap,
94 	.d_kqfilter = nokqfilter,
95 	.d_discard = nodiscard,
96 	.d_flag = D_DISK
97 };
98 
99 static int cgd_match(device_t, cfdata_t, void *);
100 static void cgd_attach(device_t, device_t, void *);
101 static int cgd_detach(device_t, int);
102 static struct cgd_softc	*cgd_spawn(int);
103 static int cgd_destroy(device_t);
104 
105 /* Internal Functions */
106 
107 static void	cgdstart(struct dk_softc *);
108 static void	cgdiodone(struct buf *);
109 
110 static int	cgd_ioctl_set(struct cgd_softc *, void *, struct lwp *);
111 static int	cgd_ioctl_clr(struct cgd_softc *, struct lwp *);
112 static int	cgd_ioctl_get(dev_t, void *, struct lwp *);
113 static int	cgdinit(struct cgd_softc *, const char *, struct vnode *,
114 			struct lwp *);
115 static void	cgd_cipher(struct cgd_softc *, void *, void *,
116 			   size_t, daddr_t, size_t, int);
117 
118 /* Pseudo-disk Interface */
119 
120 static struct dk_intf the_dkintf = {
121 	DTYPE_CGD,
122 	"cgd",
123 	cgdopen,
124 	cgdclose,
125 	cgdstrategy,
126 	cgdstart,
127 };
128 static struct dk_intf *di = &the_dkintf;
129 
130 static struct dkdriver cgddkdriver = {
131 	.d_strategy = cgdstrategy,
132 	.d_minphys = minphys,
133 };
134 
135 CFATTACH_DECL3_NEW(cgd, sizeof(struct cgd_softc),
136     cgd_match, cgd_attach, cgd_detach, NULL, NULL, NULL, DVF_DETACH_SHUTDOWN);
137 extern struct cfdriver cgd_cd;
138 
139 /* DIAGNOSTIC and DEBUG definitions */
140 
141 #if defined(CGDDEBUG) && !defined(DEBUG)
142 #define DEBUG
143 #endif
144 
145 #ifdef DEBUG
146 int cgddebug = 0;
147 
148 #define CGDB_FOLLOW	0x1
149 #define CGDB_IO	0x2
150 #define CGDB_CRYPTO	0x4
151 
152 #define IFDEBUG(x,y)		if (cgddebug & (x)) y
153 #define DPRINTF(x,y)		IFDEBUG(x, printf y)
154 #define DPRINTF_FOLLOW(y)	DPRINTF(CGDB_FOLLOW, y)
155 
156 static void	hexprint(const char *, void *, int);
157 
158 #else
159 #define IFDEBUG(x,y)
160 #define DPRINTF(x,y)
161 #define DPRINTF_FOLLOW(y)
162 #endif
163 
164 #ifdef DIAGNOSTIC
165 #define DIAGPANIC(x)		panic x
166 #define DIAGCONDPANIC(x,y)	if (x) panic y
167 #else
168 #define DIAGPANIC(x)
169 #define DIAGCONDPANIC(x,y)
170 #endif
171 
172 /* Global variables */
173 
174 /* Utility Functions */
175 
176 #define CGDUNIT(x)		DISKUNIT(x)
177 #define GETCGD_SOFTC(_cs, x)	if (!((_cs) = getcgd_softc(x))) return ENXIO
178 
179 /* The code */
180 
181 static struct cgd_softc *
182 getcgd_softc(dev_t dev)
183 {
184 	int	unit = CGDUNIT(dev);
185 	struct cgd_softc *sc;
186 
187 	DPRINTF_FOLLOW(("getcgd_softc(0x%"PRIx64"): unit = %d\n", dev, unit));
188 
189 	sc = device_lookup_private(&cgd_cd, unit);
190 	if (sc == NULL)
191 		sc = cgd_spawn(unit);
192 	return sc;
193 }
194 
195 static int
196 cgd_match(device_t self, cfdata_t cfdata, void *aux)
197 {
198 
199 	return 1;
200 }
201 
202 static void
203 cgd_attach(device_t parent, device_t self, void *aux)
204 {
205 	struct cgd_softc *sc = device_private(self);
206 
207 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_BIO);
208 	dk_sc_init(&sc->sc_dksc, device_xname(self));
209 	sc->sc_dksc.sc_dev = self;
210 	disk_init(&sc->sc_dksc.sc_dkdev, sc->sc_dksc.sc_xname, &cgddkdriver);
211 
212 	 if (!pmf_device_register(self, NULL, NULL))
213 		aprint_error_dev(self, "unable to register power management hooks\n");
214 }
215 
216 
217 static int
218 cgd_detach(device_t self, int flags)
219 {
220 	int ret;
221 	const int pmask = 1 << RAW_PART;
222 	struct cgd_softc *sc = device_private(self);
223 	struct dk_softc *dksc = &sc->sc_dksc;
224 
225 	if (DK_BUSY(dksc, pmask))
226 		return EBUSY;
227 
228 	if ((dksc->sc_flags & DKF_INITED) != 0 &&
229 	    (ret = cgd_ioctl_clr(sc, curlwp)) != 0)
230 		return ret;
231 
232 	disk_destroy(&dksc->sc_dkdev);
233 	mutex_destroy(&sc->sc_lock);
234 
235 	return 0;
236 }
237 
238 void
239 cgdattach(int num)
240 {
241 	int error;
242 
243 	error = config_cfattach_attach(cgd_cd.cd_name, &cgd_ca);
244 	if (error != 0)
245 		aprint_error("%s: unable to register cfattach\n",
246 		    cgd_cd.cd_name);
247 }
248 
249 static struct cgd_softc *
250 cgd_spawn(int unit)
251 {
252 	cfdata_t cf;
253 
254 	cf = malloc(sizeof(*cf), M_DEVBUF, M_WAITOK);
255 	cf->cf_name = cgd_cd.cd_name;
256 	cf->cf_atname = cgd_cd.cd_name;
257 	cf->cf_unit = unit;
258 	cf->cf_fstate = FSTATE_STAR;
259 
260 	return device_private(config_attach_pseudo(cf));
261 }
262 
263 static int
264 cgd_destroy(device_t dev)
265 {
266 	int error;
267 	cfdata_t cf;
268 
269 	cf = device_cfdata(dev);
270 	error = config_detach(dev, DETACH_QUIET);
271 	if (error)
272 		return error;
273 	free(cf, M_DEVBUF);
274 	return 0;
275 }
276 
277 static int
278 cgdopen(dev_t dev, int flags, int fmt, struct lwp *l)
279 {
280 	struct	cgd_softc *cs;
281 
282 	DPRINTF_FOLLOW(("cgdopen(0x%"PRIx64", %d)\n", dev, flags));
283 	GETCGD_SOFTC(cs, dev);
284 	return dk_open(di, &cs->sc_dksc, dev, flags, fmt, l);
285 }
286 
287 static int
288 cgdclose(dev_t dev, int flags, int fmt, struct lwp *l)
289 {
290 	int error;
291 	struct	cgd_softc *cs;
292 	struct	dk_softc *dksc;
293 
294 	DPRINTF_FOLLOW(("cgdclose(0x%"PRIx64", %d)\n", dev, flags));
295 	GETCGD_SOFTC(cs, dev);
296 	dksc = &cs->sc_dksc;
297 	if ((error =  dk_close(di, dksc, dev, flags, fmt, l)) != 0)
298 		return error;
299 
300 	if ((dksc->sc_flags & DKF_INITED) == 0) {
301 		if ((error = cgd_destroy(cs->sc_dksc.sc_dev)) != 0) {
302 			aprint_error_dev(dksc->sc_dev,
303 			    "unable to detach instance\n");
304 			return error;
305 		}
306 	}
307 	return 0;
308 }
309 
310 static void
311 cgdstrategy(struct buf *bp)
312 {
313 	struct	cgd_softc *cs = getcgd_softc(bp->b_dev);
314 
315 	DPRINTF_FOLLOW(("cgdstrategy(%p): b_bcount = %ld\n", bp,
316 	    (long)bp->b_bcount));
317 
318 	/*
319 	 * Reject unaligned writes.  We can encrypt and decrypt only
320 	 * complete disk sectors, and we let the ciphers require their
321 	 * buffers to be aligned to 32-bit boundaries.
322 	 */
323 	if (bp->b_blkno < 0 ||
324 	    (bp->b_bcount % DEV_BSIZE) != 0 ||
325 	    ((uintptr_t)bp->b_data & 3) != 0) {
326 		bp->b_error = EINVAL;
327 		bp->b_resid = bp->b_bcount;
328 		biodone(bp);
329 		return;
330 	}
331 
332 	/* XXXrcd: Should we test for (cs != NULL)? */
333 	dk_strategy(di, &cs->sc_dksc, bp);
334 	return;
335 }
336 
337 static int
338 cgdsize(dev_t dev)
339 {
340 	struct cgd_softc *cs = getcgd_softc(dev);
341 
342 	DPRINTF_FOLLOW(("cgdsize(0x%"PRIx64")\n", dev));
343 	if (!cs)
344 		return -1;
345 	return dk_size(di, &cs->sc_dksc, dev);
346 }
347 
348 /*
349  * cgd_{get,put}data are functions that deal with getting a buffer
350  * for the new encrypted data.  We have a buffer per device so that
351  * we can ensure that we can always have a transaction in flight.
352  * We use this buffer first so that we have one less piece of
353  * malloc'ed data at any given point.
354  */
355 
356 static void *
357 cgd_getdata(struct dk_softc *dksc, unsigned long size)
358 {
359 	struct	cgd_softc *cs = (struct cgd_softc *)dksc;
360 	void *	data = NULL;
361 
362 	mutex_enter(&cs->sc_lock);
363 	if (cs->sc_data_used == 0) {
364 		cs->sc_data_used = 1;
365 		data = cs->sc_data;
366 	}
367 	mutex_exit(&cs->sc_lock);
368 
369 	if (data)
370 		return data;
371 
372 	return malloc(size, M_DEVBUF, M_NOWAIT);
373 }
374 
375 static void
376 cgd_putdata(struct dk_softc *dksc, void *data)
377 {
378 	struct	cgd_softc *cs = (struct cgd_softc *)dksc;
379 
380 	if (data == cs->sc_data) {
381 		mutex_enter(&cs->sc_lock);
382 		cs->sc_data_used = 0;
383 		mutex_exit(&cs->sc_lock);
384 	} else {
385 		free(data, M_DEVBUF);
386 	}
387 }
388 
389 static void
390 cgdstart(struct dk_softc *dksc)
391 {
392 	struct	cgd_softc *cs = (struct cgd_softc *)dksc;
393 	struct	buf *bp, *nbp;
394 #ifdef DIAGNOSTIC
395 	struct	buf *qbp;
396 #endif
397 	void *	addr;
398 	void *	newaddr;
399 	daddr_t	bn;
400 	struct	vnode *vp;
401 
402 	while ((bp = bufq_peek(dksc->sc_bufq)) != NULL) {
403 
404 		DPRINTF_FOLLOW(("cgdstart(%p, %p)\n", dksc, bp));
405 		disk_busy(&dksc->sc_dkdev);
406 
407 		bn = bp->b_rawblkno;
408 
409 		/*
410 		 * We attempt to allocate all of our resources up front, so that
411 		 * we can fail quickly if they are unavailable.
412 		 */
413 		nbp = getiobuf(cs->sc_tvn, false);
414 		if (nbp == NULL) {
415 			disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
416 			break;
417 		}
418 
419 		/*
420 		 * If we are writing, then we need to encrypt the outgoing
421 		 * block into a new block of memory.
422 		 */
423 		newaddr = addr = bp->b_data;
424 		if ((bp->b_flags & B_READ) == 0) {
425 			newaddr = cgd_getdata(dksc, bp->b_bcount);
426 			if (!newaddr) {
427 				putiobuf(nbp);
428 				disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
429 				break;
430 			}
431 			cgd_cipher(cs, newaddr, addr, bp->b_bcount, bn,
432 			    DEV_BSIZE, CGD_CIPHER_ENCRYPT);
433 		}
434 		/* we now have all needed resources to process this buf */
435 #ifdef DIAGNOSTIC
436 		qbp = bufq_get(dksc->sc_bufq);
437 		KASSERT(bp == qbp);
438 #else
439 		(void)bufq_get(dksc->sc_bufq);
440 #endif
441 		nbp->b_data = newaddr;
442 		nbp->b_flags = bp->b_flags;
443 		nbp->b_oflags = bp->b_oflags;
444 		nbp->b_cflags = bp->b_cflags;
445 		nbp->b_iodone = cgdiodone;
446 		nbp->b_proc = bp->b_proc;
447 		nbp->b_blkno = bn;
448 		nbp->b_bcount = bp->b_bcount;
449 		nbp->b_private = bp;
450 
451 		BIO_COPYPRIO(nbp, bp);
452 
453 		if ((nbp->b_flags & B_READ) == 0) {
454 			vp = nbp->b_vp;
455 			mutex_enter(vp->v_interlock);
456 			vp->v_numoutput++;
457 			mutex_exit(vp->v_interlock);
458 		}
459 		VOP_STRATEGY(cs->sc_tvn, nbp);
460 	}
461 }
462 
463 static void
464 cgdiodone(struct buf *nbp)
465 {
466 	struct	buf *obp = nbp->b_private;
467 	struct	cgd_softc *cs = getcgd_softc(obp->b_dev);
468 	struct	dk_softc *dksc = &cs->sc_dksc;
469 	int s;
470 
471 	KDASSERT(cs);
472 
473 	DPRINTF_FOLLOW(("cgdiodone(%p)\n", nbp));
474 	DPRINTF(CGDB_IO, ("cgdiodone: bp %p bcount %d resid %d\n",
475 	    obp, obp->b_bcount, obp->b_resid));
476 	DPRINTF(CGDB_IO, (" dev 0x%"PRIx64", nbp %p bn %" PRId64 " addr %p bcnt %d\n",
477 	    nbp->b_dev, nbp, nbp->b_blkno, nbp->b_data,
478 	    nbp->b_bcount));
479 	if (nbp->b_error != 0) {
480 		obp->b_error = nbp->b_error;
481 		DPRINTF(CGDB_IO, ("%s: error %d\n", dksc->sc_xname,
482 		    obp->b_error));
483 	}
484 
485 	/* Perform the decryption if we are reading.
486 	 *
487 	 * Note: use the blocknumber from nbp, since it is what
488 	 *       we used to encrypt the blocks.
489 	 */
490 
491 	if (nbp->b_flags & B_READ)
492 		cgd_cipher(cs, obp->b_data, obp->b_data, obp->b_bcount,
493 		    nbp->b_blkno, DEV_BSIZE, CGD_CIPHER_DECRYPT);
494 
495 	/* If we allocated memory, free it now... */
496 	if (nbp->b_data != obp->b_data)
497 		cgd_putdata(dksc, nbp->b_data);
498 
499 	putiobuf(nbp);
500 
501 	/* Request is complete for whatever reason */
502 	obp->b_resid = 0;
503 	if (obp->b_error != 0)
504 		obp->b_resid = obp->b_bcount;
505 	s = splbio();
506 	disk_unbusy(&dksc->sc_dkdev, obp->b_bcount - obp->b_resid,
507 	    (obp->b_flags & B_READ));
508 	biodone(obp);
509 	cgdstart(dksc);
510 	splx(s);
511 }
512 
513 /* XXX: we should probably put these into dksubr.c, mostly */
514 static int
515 cgdread(dev_t dev, struct uio *uio, int flags)
516 {
517 	struct	cgd_softc *cs;
518 	struct	dk_softc *dksc;
519 
520 	DPRINTF_FOLLOW(("cgdread(0x%llx, %p, %d)\n",
521 	    (unsigned long long)dev, uio, flags));
522 	GETCGD_SOFTC(cs, dev);
523 	dksc = &cs->sc_dksc;
524 	if ((dksc->sc_flags & DKF_INITED) == 0)
525 		return ENXIO;
526 	return physio(cgdstrategy, NULL, dev, B_READ, minphys, uio);
527 }
528 
529 /* XXX: we should probably put these into dksubr.c, mostly */
530 static int
531 cgdwrite(dev_t dev, struct uio *uio, int flags)
532 {
533 	struct	cgd_softc *cs;
534 	struct	dk_softc *dksc;
535 
536 	DPRINTF_FOLLOW(("cgdwrite(0x%"PRIx64", %p, %d)\n", dev, uio, flags));
537 	GETCGD_SOFTC(cs, dev);
538 	dksc = &cs->sc_dksc;
539 	if ((dksc->sc_flags & DKF_INITED) == 0)
540 		return ENXIO;
541 	return physio(cgdstrategy, NULL, dev, B_WRITE, minphys, uio);
542 }
543 
544 static int
545 cgdioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
546 {
547 	struct	cgd_softc *cs;
548 	struct	dk_softc *dksc;
549 	int	part = DISKPART(dev);
550 	int	pmask = 1 << part;
551 
552 	DPRINTF_FOLLOW(("cgdioctl(0x%"PRIx64", %ld, %p, %d, %p)\n",
553 	    dev, cmd, data, flag, l));
554 
555 	switch (cmd) {
556 	case CGDIOCGET: /* don't call cgd_spawn() if the device isn't there */
557 		cs = NULL;
558 		dksc = NULL;
559 		break;
560 	case CGDIOCSET:
561 	case CGDIOCCLR:
562 		if ((flag & FWRITE) == 0)
563 			return EBADF;
564 		/* FALLTHROUGH */
565 	default:
566 		GETCGD_SOFTC(cs, dev);
567 		dksc = &cs->sc_dksc;
568 		break;
569 	}
570 
571 	switch (cmd) {
572 	case CGDIOCSET:
573 		if (dksc->sc_flags & DKF_INITED)
574 			return EBUSY;
575 		return cgd_ioctl_set(cs, data, l);
576 	case CGDIOCCLR:
577 		if (DK_BUSY(&cs->sc_dksc, pmask))
578 			return EBUSY;
579 		return cgd_ioctl_clr(cs, l);
580 	case CGDIOCGET:
581 		return cgd_ioctl_get(dev, data, l);
582 	case DIOCCACHESYNC:
583 		/*
584 		 * XXX Do we really need to care about having a writable
585 		 * file descriptor here?
586 		 */
587 		if ((flag & FWRITE) == 0)
588 			return (EBADF);
589 
590 		/*
591 		 * We pass this call down to the underlying disk.
592 		 */
593 		return VOP_IOCTL(cs->sc_tvn, cmd, data, flag, l->l_cred);
594 	default:
595 		return dk_ioctl(di, dksc, dev, cmd, data, flag, l);
596 	}
597 }
598 
599 static int
600 cgddump(dev_t dev, daddr_t blkno, void *va, size_t size)
601 {
602 	struct	cgd_softc *cs;
603 
604 	DPRINTF_FOLLOW(("cgddump(0x%"PRIx64", %" PRId64 ", %p, %lu)\n",
605 	    dev, blkno, va, (unsigned long)size));
606 	GETCGD_SOFTC(cs, dev);
607 	return dk_dump(di, &cs->sc_dksc, dev, blkno, va, size);
608 }
609 
610 /*
611  * XXXrcd:
612  *  for now we hardcode the maximum key length.
613  */
614 #define MAX_KEYSIZE	1024
615 
616 static const struct {
617 	const char *n;
618 	int v;
619 	int d;
620 } encblkno[] = {
621 	{ "encblkno",  CGD_CIPHER_CBC_ENCBLKNO8, 1 },
622 	{ "encblkno8", CGD_CIPHER_CBC_ENCBLKNO8, 1 },
623 	{ "encblkno1", CGD_CIPHER_CBC_ENCBLKNO1, 8 },
624 };
625 
626 /* ARGSUSED */
627 static int
628 cgd_ioctl_set(struct cgd_softc *cs, void *data, struct lwp *l)
629 {
630 	struct	 cgd_ioctl *ci = data;
631 	struct	 vnode *vp;
632 	int	 ret;
633 	size_t	 i;
634 	size_t	 keybytes;			/* key length in bytes */
635 	const char *cp;
636 	struct pathbuf *pb;
637 	char	 *inbuf;
638 	struct dk_softc *dksc = &cs->sc_dksc;
639 
640 	cp = ci->ci_disk;
641 
642 	ret = pathbuf_copyin(ci->ci_disk, &pb);
643 	if (ret != 0) {
644 		return ret;
645 	}
646 	ret = dk_lookup(pb, l, &vp);
647 	pathbuf_destroy(pb);
648 	if (ret != 0) {
649 		return ret;
650 	}
651 
652 	inbuf = malloc(MAX_KEYSIZE, M_TEMP, M_WAITOK);
653 
654 	if ((ret = cgdinit(cs, cp, vp, l)) != 0)
655 		goto bail;
656 
657 	(void)memset(inbuf, 0, MAX_KEYSIZE);
658 	ret = copyinstr(ci->ci_alg, inbuf, 256, NULL);
659 	if (ret)
660 		goto bail;
661 	cs->sc_cfuncs = cryptfuncs_find(inbuf);
662 	if (!cs->sc_cfuncs) {
663 		ret = EINVAL;
664 		goto bail;
665 	}
666 
667 	(void)memset(inbuf, 0, MAX_KEYSIZE);
668 	ret = copyinstr(ci->ci_ivmethod, inbuf, MAX_KEYSIZE, NULL);
669 	if (ret)
670 		goto bail;
671 
672 	for (i = 0; i < __arraycount(encblkno); i++)
673 		if (strcmp(encblkno[i].n, inbuf) == 0)
674 			break;
675 
676 	if (i == __arraycount(encblkno)) {
677 		ret = EINVAL;
678 		goto bail;
679 	}
680 
681 	keybytes = ci->ci_keylen / 8 + 1;
682 	if (keybytes > MAX_KEYSIZE) {
683 		ret = EINVAL;
684 		goto bail;
685 	}
686 
687 	(void)memset(inbuf, 0, MAX_KEYSIZE);
688 	ret = copyin(ci->ci_key, inbuf, keybytes);
689 	if (ret)
690 		goto bail;
691 
692 	cs->sc_cdata.cf_blocksize = ci->ci_blocksize;
693 	cs->sc_cdata.cf_mode = encblkno[i].v;
694 	cs->sc_cdata.cf_keylen = ci->ci_keylen;
695 	cs->sc_cdata.cf_priv = cs->sc_cfuncs->cf_init(ci->ci_keylen, inbuf,
696 	    &cs->sc_cdata.cf_blocksize);
697 	if (cs->sc_cdata.cf_blocksize > CGD_MAXBLOCKSIZE) {
698 	    log(LOG_WARNING, "cgd: Disallowed cipher with blocksize %zu > %u\n",
699 		cs->sc_cdata.cf_blocksize, CGD_MAXBLOCKSIZE);
700 	    cs->sc_cdata.cf_priv = NULL;
701 	}
702 
703 	/*
704 	 * The blocksize is supposed to be in bytes. Unfortunately originally
705 	 * it was expressed in bits. For compatibility we maintain encblkno
706 	 * and encblkno8.
707 	 */
708 	cs->sc_cdata.cf_blocksize /= encblkno[i].d;
709 	(void)memset(inbuf, 0, MAX_KEYSIZE);
710 	if (!cs->sc_cdata.cf_priv) {
711 		ret = EINVAL;		/* XXX is this the right error? */
712 		goto bail;
713 	}
714 	free(inbuf, M_TEMP);
715 
716 	bufq_alloc(&dksc->sc_bufq, "fcfs", 0);
717 
718 	cs->sc_data = malloc(MAXPHYS, M_DEVBUF, M_WAITOK);
719 	cs->sc_data_used = 0;
720 
721 	dksc->sc_flags |= DKF_INITED;
722 
723 	disk_set_info(dksc->sc_dev, &dksc->sc_dkdev, NULL);
724 
725 	/* Attach the disk. */
726 	disk_attach(&dksc->sc_dkdev);
727 
728 	/* Try and read the disklabel. */
729 	dk_getdisklabel(di, dksc, 0 /* XXX ? (cause of PR 41704) */);
730 
731 	/* Discover wedges on this disk. */
732 	dkwedge_discover(&dksc->sc_dkdev);
733 
734 	return 0;
735 
736 bail:
737 	free(inbuf, M_TEMP);
738 	(void)vn_close(vp, FREAD|FWRITE, l->l_cred);
739 	return ret;
740 }
741 
742 /* ARGSUSED */
743 static int
744 cgd_ioctl_clr(struct cgd_softc *cs, struct lwp *l)
745 {
746 	int	s;
747 	struct	dk_softc *dksc = &cs->sc_dksc;
748 
749 	if ((dksc->sc_flags & DKF_INITED) == 0)
750 		return ENXIO;
751 
752 	/* Delete all of our wedges. */
753 	dkwedge_delall(&dksc->sc_dkdev);
754 
755 	/* Kill off any queued buffers. */
756 	s = splbio();
757 	bufq_drain(dksc->sc_bufq);
758 	splx(s);
759 	bufq_free(dksc->sc_bufq);
760 
761 	(void)vn_close(cs->sc_tvn, FREAD|FWRITE, l->l_cred);
762 	cs->sc_cfuncs->cf_destroy(cs->sc_cdata.cf_priv);
763 	free(cs->sc_tpath, M_DEVBUF);
764 	free(cs->sc_data, M_DEVBUF);
765 	cs->sc_data_used = 0;
766 	dksc->sc_flags &= ~DKF_INITED;
767 	disk_detach(&dksc->sc_dkdev);
768 
769 	return 0;
770 }
771 
772 static int
773 cgd_ioctl_get(dev_t dev, void *data, struct lwp *l)
774 {
775 	struct cgd_softc *cs = getcgd_softc(dev);
776 	struct cgd_user *cgu;
777 	int unit;
778 	struct	dk_softc *dksc = &cs->sc_dksc;
779 
780 	unit = CGDUNIT(dev);
781 	cgu = (struct cgd_user *)data;
782 
783 	DPRINTF_FOLLOW(("cgd_ioctl_get(0x%"PRIx64", %d, %p, %p)\n",
784 			   dev, unit, data, l));
785 
786 	if (cgu->cgu_unit == -1)
787 		cgu->cgu_unit = unit;
788 
789 	if (cgu->cgu_unit < 0)
790 		return EINVAL;	/* XXX: should this be ENXIO? */
791 
792 	cs = device_lookup_private(&cgd_cd, unit);
793 	if (cs == NULL || (dksc->sc_flags & DKF_INITED) == 0) {
794 		cgu->cgu_dev = 0;
795 		cgu->cgu_alg[0] = '\0';
796 		cgu->cgu_blocksize = 0;
797 		cgu->cgu_mode = 0;
798 		cgu->cgu_keylen = 0;
799 	}
800 	else {
801 		cgu->cgu_dev = cs->sc_tdev;
802 		strlcpy(cgu->cgu_alg, cs->sc_cfuncs->cf_name,
803 		    sizeof(cgu->cgu_alg));
804 		cgu->cgu_blocksize = cs->sc_cdata.cf_blocksize;
805 		cgu->cgu_mode = cs->sc_cdata.cf_mode;
806 		cgu->cgu_keylen = cs->sc_cdata.cf_keylen;
807 	}
808 	return 0;
809 }
810 
811 static int
812 cgdinit(struct cgd_softc *cs, const char *cpath, struct vnode *vp,
813 	struct lwp *l)
814 {
815 	struct	disk_geom *dg;
816 	int	ret;
817 	char	*tmppath;
818 	uint64_t psize;
819 	unsigned secsize;
820 	struct dk_softc *dksc = &cs->sc_dksc;
821 
822 	cs->sc_tvn = vp;
823 	cs->sc_tpath = NULL;
824 
825 	tmppath = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
826 	ret = copyinstr(cpath, tmppath, MAXPATHLEN, &cs->sc_tpathlen);
827 	if (ret)
828 		goto bail;
829 	cs->sc_tpath = malloc(cs->sc_tpathlen, M_DEVBUF, M_WAITOK);
830 	memcpy(cs->sc_tpath, tmppath, cs->sc_tpathlen);
831 
832 	cs->sc_tdev = vp->v_rdev;
833 
834 	if ((ret = getdisksize(vp, &psize, &secsize)) != 0)
835 		goto bail;
836 
837 	if (psize == 0) {
838 		ret = ENODEV;
839 		goto bail;
840 	}
841 
842 	/*
843 	 * XXX here we should probe the underlying device.  If we
844 	 *     are accessing a partition of type RAW_PART, then
845 	 *     we should populate our initial geometry with the
846 	 *     geometry that we discover from the device.
847 	 */
848 	dg = &dksc->sc_dkdev.dk_geom;
849 	memset(dg, 0, sizeof(*dg));
850 	dg->dg_secperunit = psize;
851 	// XXX: Inherit?
852 	dg->dg_secsize = DEV_BSIZE;
853 	dg->dg_ntracks = 1;
854 	dg->dg_nsectors = 1024 * (1024 / dg->dg_secsize);
855 	dg->dg_ncylinders = dg->dg_secperunit / dg->dg_nsectors;
856 
857 bail:
858 	free(tmppath, M_TEMP);
859 	if (ret && cs->sc_tpath)
860 		free(cs->sc_tpath, M_DEVBUF);
861 	return ret;
862 }
863 
864 /*
865  * Our generic cipher entry point.  This takes care of the
866  * IV mode and passes off the work to the specific cipher.
867  * We implement here the IV method ``encrypted block
868  * number''.
869  *
870  * For the encryption case, we accomplish this by setting
871  * up a struct uio where the first iovec of the source is
872  * the blocknumber and the first iovec of the dest is a
873  * sink.  We then call the cipher with an IV of zero, and
874  * the right thing happens.
875  *
876  * For the decryption case, we use the same basic mechanism
877  * for symmetry, but we encrypt the block number in the
878  * first iovec.
879  *
880  * We mainly do this to avoid requiring the definition of
881  * an ECB mode.
882  *
883  * XXXrcd: for now we rely on our own crypto framework defined
884  *         in dev/cgd_crypto.c.  This will change when we
885  *         get a generic kernel crypto framework.
886  */
887 
888 static void
889 blkno2blkno_buf(char *sbuf, daddr_t blkno)
890 {
891 	int	i;
892 
893 	/* Set up the blkno in blkno_buf, here we do not care much
894 	 * about the final layout of the information as long as we
895 	 * can guarantee that each sector will have a different IV
896 	 * and that the endianness of the machine will not affect
897 	 * the representation that we have chosen.
898 	 *
899 	 * We choose this representation, because it does not rely
900 	 * on the size of buf (which is the blocksize of the cipher),
901 	 * but allows daddr_t to grow without breaking existing
902 	 * disks.
903 	 *
904 	 * Note that blkno2blkno_buf does not take a size as input,
905 	 * and hence must be called on a pre-zeroed buffer of length
906 	 * greater than or equal to sizeof(daddr_t).
907 	 */
908 	for (i=0; i < sizeof(daddr_t); i++) {
909 		*sbuf++ = blkno & 0xff;
910 		blkno >>= 8;
911 	}
912 }
913 
914 static void
915 cgd_cipher(struct cgd_softc *cs, void *dstv, void *srcv,
916     size_t len, daddr_t blkno, size_t secsize, int dir)
917 {
918 	char		*dst = dstv;
919 	char 		*src = srcv;
920 	cfunc_cipher	*cipher = cs->sc_cfuncs->cf_cipher;
921 	struct uio	dstuio;
922 	struct uio	srcuio;
923 	struct iovec	dstiov[2];
924 	struct iovec	srciov[2];
925 	size_t		blocksize = cs->sc_cdata.cf_blocksize;
926 	char		sink[CGD_MAXBLOCKSIZE];
927 	char		zero_iv[CGD_MAXBLOCKSIZE];
928 	char		blkno_buf[CGD_MAXBLOCKSIZE];
929 
930 	DPRINTF_FOLLOW(("cgd_cipher() dir=%d\n", dir));
931 
932 	DIAGCONDPANIC(len % blocksize != 0,
933 	    ("cgd_cipher: len %% blocksize != 0"));
934 
935 	/* ensure that sizeof(daddr_t) <= blocksize (for encblkno IVing) */
936 	DIAGCONDPANIC(sizeof(daddr_t) > blocksize,
937 	    ("cgd_cipher: sizeof(daddr_t) > blocksize"));
938 
939 	memset(zero_iv, 0x0, blocksize);
940 
941 	dstuio.uio_iov = dstiov;
942 	dstuio.uio_iovcnt = 2;
943 
944 	srcuio.uio_iov = srciov;
945 	srcuio.uio_iovcnt = 2;
946 
947 	dstiov[0].iov_base = sink;
948 	dstiov[0].iov_len  = blocksize;
949 	srciov[0].iov_base = blkno_buf;
950 	srciov[0].iov_len  = blocksize;
951 	dstiov[1].iov_len  = secsize;
952 	srciov[1].iov_len  = secsize;
953 
954 	for (; len > 0; len -= secsize) {
955 		dstiov[1].iov_base = dst;
956 		srciov[1].iov_base = src;
957 
958 		memset(blkno_buf, 0x0, blocksize);
959 		blkno2blkno_buf(blkno_buf, blkno);
960 		if (dir == CGD_CIPHER_DECRYPT) {
961 			dstuio.uio_iovcnt = 1;
962 			srcuio.uio_iovcnt = 1;
963 			IFDEBUG(CGDB_CRYPTO, hexprint("step 0: blkno_buf",
964 			    blkno_buf, blocksize));
965 			cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio,
966 			    zero_iv, CGD_CIPHER_ENCRYPT);
967 			memcpy(blkno_buf, sink, blocksize);
968 			dstuio.uio_iovcnt = 2;
969 			srcuio.uio_iovcnt = 2;
970 		}
971 
972 		IFDEBUG(CGDB_CRYPTO, hexprint("step 1: blkno_buf",
973 		    blkno_buf, blocksize));
974 		cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio, zero_iv, dir);
975 		IFDEBUG(CGDB_CRYPTO, hexprint("step 2: sink",
976 		    sink, blocksize));
977 
978 		dst += secsize;
979 		src += secsize;
980 		blkno++;
981 	}
982 }
983 
984 #ifdef DEBUG
985 static void
986 hexprint(const char *start, void *buf, int len)
987 {
988 	char	*c = buf;
989 
990 	DIAGCONDPANIC(len < 0, ("hexprint: called with len < 0"));
991 	printf("%s: len=%06d 0x", start, len);
992 	while (len--)
993 		printf("%02x", (unsigned char) *c++);
994 }
995 #endif
996 
997 MODULE(MODULE_CLASS_DRIVER, cgd, "dk_subr");
998 
999 #ifdef _MODULE
1000 CFDRIVER_DECL(cgd, DV_DISK, NULL);
1001 #endif
1002 
1003 static int
1004 cgd_modcmd(modcmd_t cmd, void *arg)
1005 {
1006 	int error = 0;
1007 
1008 #ifdef _MODULE
1009 	int bmajor = -1, cmajor = -1;
1010 #endif
1011 
1012 	switch (cmd) {
1013 	case MODULE_CMD_INIT:
1014 #ifdef _MODULE
1015 		error = config_cfdriver_attach(&cgd_cd);
1016 		if (error)
1017 			break;
1018 
1019 		error = config_cfattach_attach(cgd_cd.cd_name, &cgd_ca);
1020 	        if (error) {
1021 			config_cfdriver_detach(&cgd_cd);
1022 			aprint_error("%s: unable to register cfattach\n",
1023 			    cgd_cd.cd_name);
1024 			break;
1025 		}
1026 
1027 		error = devsw_attach("cgd", &cgd_bdevsw, &bmajor,
1028 		    &cgd_cdevsw, &cmajor);
1029 		if (error) {
1030 			config_cfattach_detach(cgd_cd.cd_name, &cgd_ca);
1031 			config_cfdriver_detach(&cgd_cd);
1032 			break;
1033 		}
1034 #endif
1035 		break;
1036 
1037 	case MODULE_CMD_FINI:
1038 #ifdef _MODULE
1039 		error = config_cfattach_detach(cgd_cd.cd_name, &cgd_ca);
1040 		if (error)
1041 			break;
1042 		config_cfdriver_detach(&cgd_cd);
1043 		devsw_detach(&cgd_bdevsw, &cgd_cdevsw);
1044 #endif
1045 		break;
1046 
1047 	case MODULE_CMD_STAT:
1048 		return ENOTTY;
1049 
1050 	default:
1051 		return ENOTTY;
1052 	}
1053 
1054 	return error;
1055 }
1056