xref: /netbsd-src/sys/dev/cgd.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /* $NetBSD: cgd.c,v 1.70 2010/02/11 18:24:48 joerg 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 1.70 2010/02/11 18:24:48 joerg 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/vnode.h>
50 #include <sys/conf.h>
51 #include <sys/syslog.h>
52 
53 #include <dev/dkvar.h>
54 #include <dev/cgdvar.h>
55 
56 /* Entry Point Functions */
57 
58 void	cgdattach(int);
59 
60 static dev_type_open(cgdopen);
61 static dev_type_close(cgdclose);
62 static dev_type_read(cgdread);
63 static dev_type_write(cgdwrite);
64 static dev_type_ioctl(cgdioctl);
65 static dev_type_strategy(cgdstrategy);
66 static dev_type_dump(cgddump);
67 static dev_type_size(cgdsize);
68 
69 const struct bdevsw cgd_bdevsw = {
70 	cgdopen, cgdclose, cgdstrategy, cgdioctl,
71 	cgddump, cgdsize, D_DISK
72 };
73 
74 const struct cdevsw cgd_cdevsw = {
75 	cgdopen, cgdclose, cgdread, cgdwrite, cgdioctl,
76 	nostop, notty, nopoll, nommap, nokqfilter, D_DISK
77 };
78 
79 static int cgd_match(device_t, cfdata_t, void *);
80 static void cgd_attach(device_t, device_t, void *);
81 static int cgd_detach(device_t, int);
82 static struct cgd_softc	*cgd_spawn(int);
83 static int cgd_destroy(device_t);
84 
85 /* Internal Functions */
86 
87 static int	cgdstart(struct dk_softc *, struct buf *);
88 static void	cgdiodone(struct buf *);
89 
90 static int	cgd_ioctl_set(struct cgd_softc *, void *, struct lwp *);
91 static int	cgd_ioctl_clr(struct cgd_softc *, struct lwp *);
92 static int	cgdinit(struct cgd_softc *, const char *, struct vnode *,
93 			struct lwp *);
94 static void	cgd_cipher(struct cgd_softc *, void *, void *,
95 			   size_t, daddr_t, size_t, int);
96 
97 /* Pseudo-disk Interface */
98 
99 static struct dk_intf the_dkintf = {
100 	DTYPE_CGD,
101 	"cgd",
102 	cgdopen,
103 	cgdclose,
104 	cgdstrategy,
105 	cgdstart,
106 };
107 static struct dk_intf *di = &the_dkintf;
108 
109 static struct dkdriver cgddkdriver = {
110 	.d_strategy = cgdstrategy,
111 	.d_minphys = minphys,
112 };
113 
114 CFATTACH_DECL3_NEW(cgd, sizeof(struct cgd_softc),
115     cgd_match, cgd_attach, cgd_detach, NULL, NULL, NULL, DVF_DETACH_SHUTDOWN);
116 extern struct cfdriver cgd_cd;
117 
118 /* DIAGNOSTIC and DEBUG definitions */
119 
120 #if defined(CGDDEBUG) && !defined(DEBUG)
121 #define DEBUG
122 #endif
123 
124 #ifdef DEBUG
125 int cgddebug = 0;
126 
127 #define CGDB_FOLLOW	0x1
128 #define CGDB_IO	0x2
129 #define CGDB_CRYPTO	0x4
130 
131 #define IFDEBUG(x,y)		if (cgddebug & (x)) y
132 #define DPRINTF(x,y)		IFDEBUG(x, printf y)
133 #define DPRINTF_FOLLOW(y)	DPRINTF(CGDB_FOLLOW, y)
134 
135 static void	hexprint(const char *, void *, int);
136 
137 #else
138 #define IFDEBUG(x,y)
139 #define DPRINTF(x,y)
140 #define DPRINTF_FOLLOW(y)
141 #endif
142 
143 #ifdef DIAGNOSTIC
144 #define DIAGPANIC(x)		panic x
145 #define DIAGCONDPANIC(x,y)	if (x) panic y
146 #else
147 #define DIAGPANIC(x)
148 #define DIAGCONDPANIC(x,y)
149 #endif
150 
151 /* Global variables */
152 
153 /* Utility Functions */
154 
155 #define CGDUNIT(x)		DISKUNIT(x)
156 #define GETCGD_SOFTC(_cs, x)	if (!((_cs) = getcgd_softc(x))) return ENXIO
157 
158 /* The code */
159 
160 static struct cgd_softc *
161 getcgd_softc(dev_t dev)
162 {
163 	int	unit = CGDUNIT(dev);
164 	struct cgd_softc *sc;
165 
166 	DPRINTF_FOLLOW(("getcgd_softc(0x%"PRIx64"): unit = %d\n", dev, unit));
167 
168 	sc = device_lookup_private(&cgd_cd, unit);
169 	if (sc == NULL)
170 		sc = cgd_spawn(unit);
171 	return sc;
172 }
173 
174 static int
175 cgd_match(device_t self, cfdata_t cfdata, void *aux)
176 {
177 
178 	return 1;
179 }
180 
181 static void
182 cgd_attach(device_t parent, device_t self, void *aux)
183 {
184 	struct cgd_softc *sc = device_private(self);
185 
186 	sc->sc_dev = self;
187 	simple_lock_init(&sc->sc_slock);
188 	dk_sc_init(&sc->sc_dksc, sc, device_xname(sc->sc_dev));
189 	disk_init(&sc->sc_dksc.sc_dkdev, sc->sc_dksc.sc_xname, &cgddkdriver);
190 
191 	 if (!pmf_device_register(self, NULL, NULL))
192 		aprint_error_dev(self, "unable to register power management hooks\n");
193 }
194 
195 
196 static int
197 cgd_detach(device_t self, int flags)
198 {
199 	int ret;
200 	const int pmask = 1 << RAW_PART;
201 	struct cgd_softc *sc = device_private(self);
202 	struct dk_softc *dksc = &sc->sc_dksc;
203 
204 	if (DK_BUSY(dksc, pmask))
205 		return EBUSY;
206 
207 	if ((dksc->sc_flags & DKF_INITED) != 0 &&
208 	    (ret = cgd_ioctl_clr(sc, curlwp)) != 0)
209 		return ret;
210 
211 	disk_destroy(&dksc->sc_dkdev);
212 
213 	return 0;
214 }
215 
216 void
217 cgdattach(int num)
218 {
219 	int error;
220 
221 	error = config_cfattach_attach(cgd_cd.cd_name, &cgd_ca);
222 	if (error != 0)
223 		aprint_error("%s: unable to register cfattach\n",
224 		    cgd_cd.cd_name);
225 }
226 
227 static struct cgd_softc *
228 cgd_spawn(int unit)
229 {
230 	cfdata_t cf;
231 
232 	cf = malloc(sizeof(*cf), M_DEVBUF, M_WAITOK);
233 	cf->cf_name = cgd_cd.cd_name;
234 	cf->cf_atname = cgd_cd.cd_name;
235 	cf->cf_unit = unit;
236 	cf->cf_fstate = FSTATE_STAR;
237 
238 	return device_private(config_attach_pseudo(cf));
239 }
240 
241 static int
242 cgd_destroy(device_t dev)
243 {
244 	int error;
245 	cfdata_t cf;
246 
247 	cf = device_cfdata(dev);
248 	error = config_detach(dev, DETACH_QUIET);
249 	if (error)
250 		return error;
251 	free(cf, M_DEVBUF);
252 	return 0;
253 }
254 
255 static int
256 cgdopen(dev_t dev, int flags, int fmt, struct lwp *l)
257 {
258 	struct	cgd_softc *cs;
259 
260 	DPRINTF_FOLLOW(("cgdopen(0x%"PRIx64", %d)\n", dev, flags));
261 	GETCGD_SOFTC(cs, dev);
262 	return dk_open(di, &cs->sc_dksc, dev, flags, fmt, l);
263 }
264 
265 static int
266 cgdclose(dev_t dev, int flags, int fmt, struct lwp *l)
267 {
268 	int error;
269 	struct	cgd_softc *cs;
270 	struct	dk_softc *dksc;
271 
272 	DPRINTF_FOLLOW(("cgdclose(0x%"PRIx64", %d)\n", dev, flags));
273 	GETCGD_SOFTC(cs, dev);
274 	dksc = &cs->sc_dksc;
275 	if ((error =  dk_close(di, dksc, dev, flags, fmt, l)) != 0)
276 		return error;
277 
278 	if ((dksc->sc_flags & DKF_INITED) == 0) {
279 		if ((error = cgd_destroy(cs->sc_dev)) != 0) {
280 			aprint_error_dev(cs->sc_dev,
281 			    "unable to detach instance\n");
282 			return error;
283 		}
284 	}
285 	return 0;
286 }
287 
288 static void
289 cgdstrategy(struct buf *bp)
290 {
291 	struct	cgd_softc *cs = getcgd_softc(bp->b_dev);
292 
293 	DPRINTF_FOLLOW(("cgdstrategy(%p): b_bcount = %ld\n", bp,
294 	    (long)bp->b_bcount));
295 	/* XXXrcd: Should we test for (cs != NULL)? */
296 	dk_strategy(di, &cs->sc_dksc, bp);
297 	return;
298 }
299 
300 static int
301 cgdsize(dev_t dev)
302 {
303 	struct cgd_softc *cs = getcgd_softc(dev);
304 
305 	DPRINTF_FOLLOW(("cgdsize(0x%"PRIx64")\n", dev));
306 	if (!cs)
307 		return -1;
308 	return dk_size(di, &cs->sc_dksc, dev);
309 }
310 
311 /*
312  * cgd_{get,put}data are functions that deal with getting a buffer
313  * for the new encrypted data.  We have a buffer per device so that
314  * we can ensure that we can always have a transaction in flight.
315  * We use this buffer first so that we have one less piece of
316  * malloc'ed data at any given point.
317  */
318 
319 static void *
320 cgd_getdata(struct dk_softc *dksc, unsigned long size)
321 {
322 	struct	cgd_softc *cs =dksc->sc_osc;
323 	void *	data = NULL;
324 
325 	simple_lock(&cs->sc_slock);
326 	if (cs->sc_data_used == 0) {
327 		cs->sc_data_used = 1;
328 		data = cs->sc_data;
329 	}
330 	simple_unlock(&cs->sc_slock);
331 
332 	if (data)
333 		return data;
334 
335 	return malloc(size, M_DEVBUF, M_NOWAIT);
336 }
337 
338 static void
339 cgd_putdata(struct dk_softc *dksc, void *data)
340 {
341 	struct	cgd_softc *cs =dksc->sc_osc;
342 
343 	if (data == cs->sc_data) {
344 		simple_lock(&cs->sc_slock);
345 		cs->sc_data_used = 0;
346 		simple_unlock(&cs->sc_slock);
347 	} else {
348 		free(data, M_DEVBUF);
349 	}
350 }
351 
352 static int
353 cgdstart(struct dk_softc *dksc, struct buf *bp)
354 {
355 	struct	cgd_softc *cs = dksc->sc_osc;
356 	struct	buf *nbp;
357 	void *	addr;
358 	void *	newaddr;
359 	daddr_t	bn;
360 	struct	vnode *vp;
361 
362 	DPRINTF_FOLLOW(("cgdstart(%p, %p)\n", dksc, bp));
363 	disk_busy(&dksc->sc_dkdev); /* XXX: put in dksubr.c */
364 
365 	bn = bp->b_rawblkno;
366 
367 	/*
368 	 * We attempt to allocate all of our resources up front, so that
369 	 * we can fail quickly if they are unavailable.
370 	 */
371 
372 	nbp = getiobuf(cs->sc_tvn, false);
373 	if (nbp == NULL) {
374 		disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
375 		return -1;
376 	}
377 
378 	/*
379 	 * If we are writing, then we need to encrypt the outgoing
380 	 * block into a new block of memory.  If we fail, then we
381 	 * return an error and let the dksubr framework deal with it.
382 	 */
383 	newaddr = addr = bp->b_data;
384 	if ((bp->b_flags & B_READ) == 0) {
385 		newaddr = cgd_getdata(dksc, bp->b_bcount);
386 		if (!newaddr) {
387 			putiobuf(nbp);
388 			disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
389 			return -1;
390 		}
391 		cgd_cipher(cs, newaddr, addr, bp->b_bcount, bn,
392 		    DEV_BSIZE, CGD_CIPHER_ENCRYPT);
393 	}
394 
395 	nbp->b_data = newaddr;
396 	nbp->b_flags = bp->b_flags;
397 	nbp->b_oflags = bp->b_oflags;
398 	nbp->b_cflags = bp->b_cflags;
399 	nbp->b_iodone = cgdiodone;
400 	nbp->b_proc = bp->b_proc;
401 	nbp->b_blkno = bn;
402 	nbp->b_bcount = bp->b_bcount;
403 	nbp->b_private = bp;
404 
405 	BIO_COPYPRIO(nbp, bp);
406 
407 	if ((nbp->b_flags & B_READ) == 0) {
408 		vp = nbp->b_vp;
409 		mutex_enter(&vp->v_interlock);
410 		vp->v_numoutput++;
411 		mutex_exit(&vp->v_interlock);
412 	}
413 	VOP_STRATEGY(cs->sc_tvn, nbp);
414 	return 0;
415 }
416 
417 static void
418 cgdiodone(struct buf *nbp)
419 {
420 	struct	buf *obp = nbp->b_private;
421 	struct	cgd_softc *cs = getcgd_softc(obp->b_dev);
422 	struct	dk_softc *dksc = &cs->sc_dksc;
423 	int s;
424 
425 	KDASSERT(cs);
426 
427 	DPRINTF_FOLLOW(("cgdiodone(%p)\n", nbp));
428 	DPRINTF(CGDB_IO, ("cgdiodone: bp %p bcount %d resid %d\n",
429 	    obp, obp->b_bcount, obp->b_resid));
430 	DPRINTF(CGDB_IO, (" dev 0x%"PRIx64", nbp %p bn %" PRId64 " addr %p bcnt %d\n",
431 	    nbp->b_dev, nbp, nbp->b_blkno, nbp->b_data,
432 	    nbp->b_bcount));
433 	if (nbp->b_error != 0) {
434 		obp->b_error = nbp->b_error;
435 		DPRINTF(CGDB_IO, ("%s: error %d\n", dksc->sc_xname,
436 		    obp->b_error));
437 	}
438 
439 	/* Perform the decryption if we are reading.
440 	 *
441 	 * Note: use the blocknumber from nbp, since it is what
442 	 *       we used to encrypt the blocks.
443 	 */
444 
445 	if (nbp->b_flags & B_READ)
446 		cgd_cipher(cs, obp->b_data, obp->b_data, obp->b_bcount,
447 		    nbp->b_blkno, DEV_BSIZE, CGD_CIPHER_DECRYPT);
448 
449 	/* If we allocated memory, free it now... */
450 	if (nbp->b_data != obp->b_data)
451 		cgd_putdata(dksc, nbp->b_data);
452 
453 	putiobuf(nbp);
454 
455 	/* Request is complete for whatever reason */
456 	obp->b_resid = 0;
457 	if (obp->b_error != 0)
458 		obp->b_resid = obp->b_bcount;
459 	s = splbio();
460 	disk_unbusy(&dksc->sc_dkdev, obp->b_bcount - obp->b_resid,
461 	    (obp->b_flags & B_READ));
462 	biodone(obp);
463 	dk_iodone(di, dksc);
464 	splx(s);
465 }
466 
467 /* XXX: we should probably put these into dksubr.c, mostly */
468 static int
469 cgdread(dev_t dev, struct uio *uio, int flags)
470 {
471 	struct	cgd_softc *cs;
472 	struct	dk_softc *dksc;
473 
474 	DPRINTF_FOLLOW(("cgdread(0x%llx, %p, %d)\n",
475 	    (unsigned long long)dev, uio, flags));
476 	GETCGD_SOFTC(cs, dev);
477 	dksc = &cs->sc_dksc;
478 	if ((dksc->sc_flags & DKF_INITED) == 0)
479 		return ENXIO;
480 	return physio(cgdstrategy, NULL, dev, B_READ, minphys, uio);
481 }
482 
483 /* XXX: we should probably put these into dksubr.c, mostly */
484 static int
485 cgdwrite(dev_t dev, struct uio *uio, int flags)
486 {
487 	struct	cgd_softc *cs;
488 	struct	dk_softc *dksc;
489 
490 	DPRINTF_FOLLOW(("cgdwrite(0x%"PRIx64", %p, %d)\n", dev, uio, flags));
491 	GETCGD_SOFTC(cs, dev);
492 	dksc = &cs->sc_dksc;
493 	if ((dksc->sc_flags & DKF_INITED) == 0)
494 		return ENXIO;
495 	return physio(cgdstrategy, NULL, dev, B_WRITE, minphys, uio);
496 }
497 
498 static int
499 cgdioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
500 {
501 	struct	cgd_softc *cs;
502 	struct	dk_softc *dksc;
503 	struct	disk *dk;
504 	int	part = DISKPART(dev);
505 	int	pmask = 1 << part;
506 
507 	DPRINTF_FOLLOW(("cgdioctl(0x%"PRIx64", %ld, %p, %d, %p)\n",
508 	    dev, cmd, data, flag, l));
509 	GETCGD_SOFTC(cs, dev);
510 	dksc = &cs->sc_dksc;
511 	dk = &dksc->sc_dkdev;
512 	switch (cmd) {
513 	case CGDIOCSET:
514 	case CGDIOCCLR:
515 		if ((flag & FWRITE) == 0)
516 			return EBADF;
517 	}
518 
519 	switch (cmd) {
520 	case CGDIOCSET:
521 		if (dksc->sc_flags & DKF_INITED)
522 			return EBUSY;
523 		return cgd_ioctl_set(cs, data, l);
524 	case CGDIOCCLR:
525 		if (DK_BUSY(&cs->sc_dksc, pmask))
526 			return EBUSY;
527 		return cgd_ioctl_clr(cs, l);
528 	case DIOCCACHESYNC:
529 		/*
530 		 * XXX Do we really need to care about having a writable
531 		 * file descriptor here?
532 		 */
533 		if ((flag & FWRITE) == 0)
534 			return (EBADF);
535 
536 		/*
537 		 * We pass this call down to the underlying disk.
538 		 */
539 		return VOP_IOCTL(cs->sc_tvn, cmd, data, flag, l->l_cred);
540 	default:
541 		return dk_ioctl(di, dksc, dev, cmd, data, flag, l);
542 	}
543 }
544 
545 static int
546 cgddump(dev_t dev, daddr_t blkno, void *va, size_t size)
547 {
548 	struct	cgd_softc *cs;
549 
550 	DPRINTF_FOLLOW(("cgddump(0x%"PRIx64", %" PRId64 ", %p, %lu)\n",
551 	    dev, blkno, va, (unsigned long)size));
552 	GETCGD_SOFTC(cs, dev);
553 	return dk_dump(di, &cs->sc_dksc, dev, blkno, va, size);
554 }
555 
556 /*
557  * XXXrcd:
558  *  for now we hardcode the maximum key length.
559  */
560 #define MAX_KEYSIZE	1024
561 
562 static const struct {
563 	const char *n;
564 	int v;
565 	int d;
566 } encblkno[] = {
567 	{ "encblkno",  CGD_CIPHER_CBC_ENCBLKNO8, 1 },
568 	{ "encblkno8", CGD_CIPHER_CBC_ENCBLKNO8, 1 },
569 	{ "encblkno1", CGD_CIPHER_CBC_ENCBLKNO1, 8 },
570 };
571 
572 /* ARGSUSED */
573 static int
574 cgd_ioctl_set(struct cgd_softc *cs, void *data, struct lwp *l)
575 {
576 	struct	 cgd_ioctl *ci = data;
577 	struct	 vnode *vp;
578 	int	 ret;
579 	size_t	 i;
580 	size_t	 keybytes;			/* key length in bytes */
581 	const char *cp;
582 	char	 *inbuf;
583 
584 	cp = ci->ci_disk;
585 	if ((ret = dk_lookup(cp, l, &vp, UIO_USERSPACE)) != 0)
586 		return ret;
587 
588 	inbuf = malloc(MAX_KEYSIZE, M_TEMP, M_WAITOK);
589 
590 	if ((ret = cgdinit(cs, cp, vp, l)) != 0)
591 		goto bail;
592 
593 	(void)memset(inbuf, 0, MAX_KEYSIZE);
594 	ret = copyinstr(ci->ci_alg, inbuf, 256, NULL);
595 	if (ret)
596 		goto bail;
597 	cs->sc_cfuncs = cryptfuncs_find(inbuf);
598 	if (!cs->sc_cfuncs) {
599 		ret = EINVAL;
600 		goto bail;
601 	}
602 
603 	(void)memset(inbuf, 0, MAX_KEYSIZE);
604 	ret = copyinstr(ci->ci_ivmethod, inbuf, MAX_KEYSIZE, NULL);
605 	if (ret)
606 		goto bail;
607 
608 	for (i = 0; i < __arraycount(encblkno); i++)
609 		if (strcmp(encblkno[i].n, inbuf) == 0)
610 			break;
611 
612 	if (i == __arraycount(encblkno)) {
613 		ret = EINVAL;
614 		goto bail;
615 	}
616 
617 	keybytes = ci->ci_keylen / 8 + 1;
618 	if (keybytes > MAX_KEYSIZE) {
619 		ret = EINVAL;
620 		goto bail;
621 	}
622 
623 	(void)memset(inbuf, 0, MAX_KEYSIZE);
624 	ret = copyin(ci->ci_key, inbuf, keybytes);
625 	if (ret)
626 		goto bail;
627 
628 	cs->sc_cdata.cf_blocksize = ci->ci_blocksize;
629 	cs->sc_cdata.cf_mode = encblkno[i].v;
630 	cs->sc_cdata.cf_priv = cs->sc_cfuncs->cf_init(ci->ci_keylen, inbuf,
631 	    &cs->sc_cdata.cf_blocksize);
632 	if (cs->sc_cdata.cf_blocksize > CGD_MAXBLOCKSIZE) {
633 	    log(LOG_WARNING, "cgd: Disallowed cipher with blocksize %zu > %u\n",
634 		cs->sc_cdata.cf_blocksize, CGD_MAXBLOCKSIZE);
635 	    cs->sc_cdata.cf_priv = NULL;
636 	}
637 
638 	/*
639 	 * The blocksize is supposed to be in bytes. Unfortunately originally
640 	 * it was expressed in bits. For compatibility we maintain encblkno
641 	 * and encblkno8.
642 	 */
643 	cs->sc_cdata.cf_blocksize /= encblkno[i].d;
644 	(void)memset(inbuf, 0, MAX_KEYSIZE);
645 	if (!cs->sc_cdata.cf_priv) {
646 		ret = EINVAL;		/* XXX is this the right error? */
647 		goto bail;
648 	}
649 	free(inbuf, M_TEMP);
650 
651 	bufq_alloc(&cs->sc_dksc.sc_bufq, "fcfs", 0);
652 
653 	cs->sc_data = malloc(MAXPHYS, M_DEVBUF, M_WAITOK);
654 	cs->sc_data_used = 0;
655 
656 	cs->sc_dksc.sc_flags |= DKF_INITED;
657 
658 	/* Attach the disk. */
659 	disk_attach(&cs->sc_dksc.sc_dkdev);
660 
661 	/* Try and read the disklabel. */
662 	dk_getdisklabel(di, &cs->sc_dksc, 0 /* XXX ? (cause of PR 41704) */);
663 
664 	/* Discover wedges on this disk. */
665 	dkwedge_discover(&cs->sc_dksc.sc_dkdev);
666 
667 	return 0;
668 
669 bail:
670 	free(inbuf, M_TEMP);
671 	(void)vn_close(vp, FREAD|FWRITE, l->l_cred);
672 	return ret;
673 }
674 
675 /* ARGSUSED */
676 static int
677 cgd_ioctl_clr(struct cgd_softc *cs, struct lwp *l)
678 {
679 	int	s;
680 	struct	dk_softc *dksc;
681 
682 	dksc = &cs->sc_dksc;
683 
684 	if ((dksc->sc_flags & DKF_INITED) == 0)
685 		return ENXIO;
686 
687 	/* Delete all of our wedges. */
688 	dkwedge_delall(&cs->sc_dksc.sc_dkdev);
689 
690 	/* Kill off any queued buffers. */
691 	s = splbio();
692 	bufq_drain(cs->sc_dksc.sc_bufq);
693 	splx(s);
694 	bufq_free(cs->sc_dksc.sc_bufq);
695 
696 	(void)vn_close(cs->sc_tvn, FREAD|FWRITE, l->l_cred);
697 	cs->sc_cfuncs->cf_destroy(cs->sc_cdata.cf_priv);
698 	free(cs->sc_tpath, M_DEVBUF);
699 	free(cs->sc_data, M_DEVBUF);
700 	cs->sc_data_used = 0;
701 	cs->sc_dksc.sc_flags &= ~DKF_INITED;
702 	disk_detach(&cs->sc_dksc.sc_dkdev);
703 
704 	return 0;
705 }
706 
707 static int
708 getsize(struct lwp *l, struct vnode *vp, size_t *size)
709 {
710 	struct partinfo dpart;
711 	struct dkwedge_info dkw;
712 	int ret;
713 
714 	if ((ret = VOP_IOCTL(vp, DIOCGWEDGEINFO, &dkw, FREAD,
715 	    l->l_cred)) == 0) {
716 		*size = dkw.dkw_size;
717 		return 0;
718 	}
719 
720 	if ((ret = VOP_IOCTL(vp, DIOCGPART, &dpart, FREAD, l->l_cred)) == 0) {
721 		*size = dpart.part->p_size;
722 		return 0;
723 	}
724 
725 	return ret;
726 }
727 
728 
729 static int
730 cgdinit(struct cgd_softc *cs, const char *cpath, struct vnode *vp,
731 	struct lwp *l)
732 {
733 	struct	dk_geom *pdg;
734 	struct	vattr va;
735 	size_t	size;
736 	int	ret;
737 	char	*tmppath;
738 
739 	cs->sc_dksc.sc_size = 0;
740 	cs->sc_tvn = vp;
741 	cs->sc_tpath = NULL;
742 
743 	tmppath = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
744 	ret = copyinstr(cpath, tmppath, MAXPATHLEN, &cs->sc_tpathlen);
745 	if (ret)
746 		goto bail;
747 	cs->sc_tpath = malloc(cs->sc_tpathlen, M_DEVBUF, M_WAITOK);
748 	memcpy(cs->sc_tpath, tmppath, cs->sc_tpathlen);
749 
750 	if ((ret = VOP_GETATTR(vp, &va, l->l_cred)) != 0)
751 		goto bail;
752 
753 	cs->sc_tdev = va.va_rdev;
754 
755 	if ((ret = getsize(l, vp, &size)) != 0)
756 		goto bail;
757 
758 	if (!size) {
759 		ret = ENODEV;
760 		goto bail;
761 	}
762 
763 	cs->sc_dksc.sc_size = size;
764 
765 	/*
766 	 * XXX here we should probe the underlying device.  If we
767 	 *     are accessing a partition of type RAW_PART, then
768 	 *     we should populate our initial geometry with the
769 	 *     geometry that we discover from the device.
770 	 */
771 	pdg = &cs->sc_dksc.sc_geom;
772 	pdg->pdg_secsize = DEV_BSIZE;
773 	pdg->pdg_ntracks = 1;
774 	pdg->pdg_nsectors = 1024 * (1024 / pdg->pdg_secsize);
775 	pdg->pdg_ncylinders = cs->sc_dksc.sc_size / pdg->pdg_nsectors;
776 
777 bail:
778 	free(tmppath, M_TEMP);
779 	if (ret && cs->sc_tpath)
780 		free(cs->sc_tpath, M_DEVBUF);
781 	return ret;
782 }
783 
784 /*
785  * Our generic cipher entry point.  This takes care of the
786  * IV mode and passes off the work to the specific cipher.
787  * We implement here the IV method ``encrypted block
788  * number''.
789  *
790  * For the encryption case, we accomplish this by setting
791  * up a struct uio where the first iovec of the source is
792  * the blocknumber and the first iovec of the dest is a
793  * sink.  We then call the cipher with an IV of zero, and
794  * the right thing happens.
795  *
796  * For the decryption case, we use the same basic mechanism
797  * for symmetry, but we encrypt the block number in the
798  * first iovec.
799  *
800  * We mainly do this to avoid requiring the definition of
801  * an ECB mode.
802  *
803  * XXXrcd: for now we rely on our own crypto framework defined
804  *         in dev/cgd_crypto.c.  This will change when we
805  *         get a generic kernel crypto framework.
806  */
807 
808 static void
809 blkno2blkno_buf(char *sbuf, daddr_t blkno)
810 {
811 	int	i;
812 
813 	/* Set up the blkno in blkno_buf, here we do not care much
814 	 * about the final layout of the information as long as we
815 	 * can guarantee that each sector will have a different IV
816 	 * and that the endianness of the machine will not affect
817 	 * the representation that we have chosen.
818 	 *
819 	 * We choose this representation, because it does not rely
820 	 * on the size of buf (which is the blocksize of the cipher),
821 	 * but allows daddr_t to grow without breaking existing
822 	 * disks.
823 	 *
824 	 * Note that blkno2blkno_buf does not take a size as input,
825 	 * and hence must be called on a pre-zeroed buffer of length
826 	 * greater than or equal to sizeof(daddr_t).
827 	 */
828 	for (i=0; i < sizeof(daddr_t); i++) {
829 		*sbuf++ = blkno & 0xff;
830 		blkno >>= 8;
831 	}
832 }
833 
834 static void
835 cgd_cipher(struct cgd_softc *cs, void *dstv, void *srcv,
836     size_t len, daddr_t blkno, size_t secsize, int dir)
837 {
838 	char		*dst = dstv;
839 	char 		*src = srcv;
840 	cfunc_cipher	*cipher = cs->sc_cfuncs->cf_cipher;
841 	struct uio	dstuio;
842 	struct uio	srcuio;
843 	struct iovec	dstiov[2];
844 	struct iovec	srciov[2];
845 	size_t		blocksize = cs->sc_cdata.cf_blocksize;
846 	char		sink[CGD_MAXBLOCKSIZE];
847 	char		zero_iv[CGD_MAXBLOCKSIZE];
848 	char		blkno_buf[CGD_MAXBLOCKSIZE];
849 
850 	DPRINTF_FOLLOW(("cgd_cipher() dir=%d\n", dir));
851 
852 	DIAGCONDPANIC(len % blocksize != 0,
853 	    ("cgd_cipher: len %% blocksize != 0"));
854 
855 	/* ensure that sizeof(daddr_t) <= blocksize (for encblkno IVing) */
856 	DIAGCONDPANIC(sizeof(daddr_t) > blocksize,
857 	    ("cgd_cipher: sizeof(daddr_t) > blocksize"));
858 
859 	memset(zero_iv, 0x0, blocksize);
860 
861 	dstuio.uio_iov = dstiov;
862 	dstuio.uio_iovcnt = 2;
863 
864 	srcuio.uio_iov = srciov;
865 	srcuio.uio_iovcnt = 2;
866 
867 	dstiov[0].iov_base = sink;
868 	dstiov[0].iov_len  = blocksize;
869 	srciov[0].iov_base = blkno_buf;
870 	srciov[0].iov_len  = blocksize;
871 	dstiov[1].iov_len  = secsize;
872 	srciov[1].iov_len  = secsize;
873 
874 	for (; len > 0; len -= secsize) {
875 		dstiov[1].iov_base = dst;
876 		srciov[1].iov_base = src;
877 
878 		memset(blkno_buf, 0x0, blocksize);
879 		blkno2blkno_buf(blkno_buf, blkno);
880 		if (dir == CGD_CIPHER_DECRYPT) {
881 			dstuio.uio_iovcnt = 1;
882 			srcuio.uio_iovcnt = 1;
883 			IFDEBUG(CGDB_CRYPTO, hexprint("step 0: blkno_buf",
884 			    blkno_buf, blocksize));
885 			cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio,
886 			    zero_iv, CGD_CIPHER_ENCRYPT);
887 			memcpy(blkno_buf, sink, blocksize);
888 			dstuio.uio_iovcnt = 2;
889 			srcuio.uio_iovcnt = 2;
890 		}
891 
892 		IFDEBUG(CGDB_CRYPTO, hexprint("step 1: blkno_buf",
893 		    blkno_buf, blocksize));
894 		cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio, zero_iv, dir);
895 		IFDEBUG(CGDB_CRYPTO, hexprint("step 2: sink",
896 		    sink, blocksize));
897 
898 		dst += secsize;
899 		src += secsize;
900 		blkno++;
901 	}
902 }
903 
904 #ifdef DEBUG
905 static void
906 hexprint(const char *start, void *buf, int len)
907 {
908 	char	*c = buf;
909 
910 	DIAGCONDPANIC(len < 0, ("hexprint: called with len < 0"));
911 	printf("%s: len=%06d 0x", start, len);
912 	while (len--)
913 		printf("%02x", (unsigned char) *c++);
914 }
915 #endif
916 
917 #ifdef _MODULE
918 
919 #include <sys/module.h>
920 
921 MODULE(MODULE_CLASS_DRIVER, cgd, NULL);
922 CFDRIVER_DECL(cgd, DV_DISK, NULL);
923 
924 static int
925 cgd_modcmd(modcmd_t cmd, void *arg)
926 {
927 	int bmajor = -1, cmajor = -1,  error = 0;
928 
929 	switch (cmd) {
930 	case MODULE_CMD_INIT:
931 		error = config_cfdriver_attach(&cgd_cd);
932 		if (error)
933 			break;
934 
935 		error = config_cfattach_attach(cgd_cd.cd_name, &cgd_ca);
936 	        if (error) {
937 			config_cfdriver_detach(&cgd_cd);
938 			aprint_error("%s: unable to register cfattach\n",
939 			    cgd_cd.cd_name);
940 			break;
941 		}
942 
943 		error = devsw_attach("cgd", &cgd_bdevsw, &bmajor,
944 		    &cgd_cdevsw, &cmajor);
945 		if (error) {
946 			config_cfattach_detach(cgd_cd.cd_name, &cgd_ca);
947 			config_cfdriver_detach(&cgd_cd);
948 			break;
949 		}
950 
951 		break;
952 
953 	case MODULE_CMD_FINI:
954 		error = config_cfattach_detach(cgd_cd.cd_name, &cgd_ca);
955 		if (error)
956 			break;
957 		config_cfdriver_detach(&cgd_cd);
958 		devsw_detach(&cgd_bdevsw, &cgd_cdevsw);
959 		break;
960 
961 	case MODULE_CMD_STAT:
962 		return ENOTTY;
963 
964 	default:
965 		return ENOTTY;
966 	}
967 
968 	return error;
969 }
970 
971 #endif
972