1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2002 Poul-Henning Kamp
5 * Copyright (c) 2002 Networks Associates Technology, Inc.
6 * All rights reserved.
7 *
8 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
9 * and NAI Labs, the Security Research Division of Network Associates, Inc.
10 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
11 * DARPA CHATS research program.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * $FreeBSD$
35 *
36 */
37
38#include <sys/param.h>
39#include <sys/bio.h>
40#include <sys/lock.h>
41#include <sys/mutex.h>
42#include <sys/malloc.h>
43#include <sys/systm.h>
44#include <sys/kernel.h>
45#include <sys/kthread.h>
46#include <sys/sysctl.h>
47
48#include <crypto/rijndael/rijndael-api-fst.h>
49#include <crypto/sha2/sha512.h>
50#include <geom/geom.h>
51#include <geom/bde/g_bde.h>
52#define BDE_CLASS_NAME "BDE"
53
54FEATURE(geom_bde, "GEOM-based Disk Encryption");
55
56static void
57g_bde_start(struct bio *bp)
58{
59
60	switch (bp->bio_cmd) {
61	case BIO_DELETE:
62	case BIO_READ:
63	case BIO_WRITE:
64		g_bde_start1(bp);
65		break;
66	case BIO_GETATTR:
67		g_io_deliver(bp, EOPNOTSUPP);
68		break;
69	default:
70		g_io_deliver(bp, EOPNOTSUPP);
71		return;
72	}
73	return;
74}
75
76static void
77g_bde_orphan(struct g_consumer *cp)
78{
79	struct g_geom *gp;
80	struct g_provider *pp;
81	struct g_bde_softc *sc;
82
83	g_trace(G_T_TOPOLOGY, "g_bde_orphan(%p/%s)", cp, cp->provider->name);
84	g_topology_assert();
85
86	gp = cp->geom;
87	sc = gp->softc;
88	gp->flags |= G_GEOM_WITHER;
89	LIST_FOREACH(pp, &gp->provider, provider)
90		g_wither_provider(pp, ENXIO);
91	explicit_bzero(sc, sizeof(struct g_bde_softc));	/* destroy evidence */
92	return;
93}
94
95static int
96g_bde_access(struct g_provider *pp, int dr, int dw, int de)
97{
98	struct g_geom *gp;
99	struct g_consumer *cp;
100
101	gp = pp->geom;
102	cp = LIST_FIRST(&gp->consumer);
103	if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0) {
104		de++;
105		dr++;
106	}
107	/* ... and let go of it on last close */
108	if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1) {
109		de--;
110		dr--;
111	}
112	return (g_access(cp, dr, dw, de));
113}
114
115static void
116g_bde_create_geom(struct gctl_req *req, struct g_class *mp, struct g_provider *pp)
117{
118	struct g_geom *gp;
119	struct g_consumer *cp;
120	struct g_bde_key *kp;
121	int error, i;
122	u_int sectorsize;
123	off_t mediasize;
124	struct g_bde_softc *sc;
125	void *pass;
126	void *key;
127
128	g_trace(G_T_TOPOLOGY, "g_bde_create_geom(%s, %s)", mp->name, pp->name);
129	g_topology_assert();
130	gp = NULL;
131
132	gp = g_new_geomf(mp, "%s.bde", pp->name);
133	cp = g_new_consumer(gp);
134	error = g_attach(cp, pp);
135	if (error != 0) {
136		g_destroy_consumer(cp);
137		g_destroy_geom(gp);
138		gctl_error(req, "could not attach consumer");
139		return;
140	}
141	error = g_access(cp, 1, 1, 1);
142	if (error) {
143		g_detach(cp);
144		g_destroy_consumer(cp);
145		g_destroy_geom(gp);
146		gctl_error(req, "could not access consumer");
147		return;
148	}
149	pass = NULL;
150	key = NULL;
151	do {
152		pass = gctl_get_param(req, "pass", &i);
153		if (pass == NULL || i != SHA512_DIGEST_LENGTH) {
154			gctl_error(req, "No usable key presented");
155			break;
156		}
157		key = gctl_get_param(req, "key", &i);
158		if (key != NULL && i != 16) {
159			gctl_error(req, "Invalid key presented");
160			break;
161		}
162		sectorsize = cp->provider->sectorsize;
163		mediasize = cp->provider->mediasize;
164		sc = g_malloc(sizeof(struct g_bde_softc), M_WAITOK | M_ZERO);
165		gp->softc = sc;
166		sc->geom = gp;
167		sc->consumer = cp;
168
169		error = g_bde_decrypt_lock(sc, pass, key,
170		    mediasize, sectorsize, NULL);
171		explicit_bzero(sc->sha2, sizeof sc->sha2);
172		if (error)
173			break;
174		kp = &sc->key;
175
176		/* Initialize helper-fields */
177		kp->keys_per_sector = kp->sectorsize / G_BDE_SKEYLEN;
178		kp->zone_cont = kp->keys_per_sector * kp->sectorsize;
179		kp->zone_width = kp->zone_cont + kp->sectorsize;
180		kp->media_width = kp->sectorN - kp->sector0 -
181		    G_BDE_MAXKEYS * kp->sectorsize;
182
183		/* Our external parameters */
184		sc->zone_cont = kp->zone_cont;
185		sc->mediasize = g_bde_max_sector(kp);
186		sc->sectorsize = kp->sectorsize;
187
188		TAILQ_INIT(&sc->freelist);
189		TAILQ_INIT(&sc->worklist);
190		mtx_init(&sc->worklist_mutex, "g_bde_worklist", NULL, MTX_DEF);
191		/* XXX: error check */
192		kproc_create(g_bde_worker, gp, &sc->thread, 0, 0,
193			"g_bde %s", gp->name);
194		pp = g_new_providerf(gp, "%s", gp->name);
195		pp->stripesize = kp->zone_cont;
196		pp->stripeoffset = 0;
197		pp->mediasize = sc->mediasize;
198		pp->sectorsize = sc->sectorsize;
199		g_error_provider(pp, 0);
200		break;
201	} while (0);
202	if (pass != NULL)
203		explicit_bzero(pass, SHA512_DIGEST_LENGTH);
204	if (key != NULL)
205		explicit_bzero(key, 16);
206	if (error == 0)
207		return;
208	g_access(cp, -1, -1, -1);
209	g_detach(cp);
210	g_destroy_consumer(cp);
211	if (gp->softc != NULL)
212		g_free(gp->softc);
213	g_destroy_geom(gp);
214	switch (error) {
215	case ENOENT:
216		gctl_error(req, "Lock was destroyed");
217		break;
218	case ESRCH:
219		gctl_error(req, "Lock was nuked");
220		break;
221	case EINVAL:
222		gctl_error(req, "Could not open lock");
223		break;
224	case ENOTDIR:
225		gctl_error(req, "Lock not found");
226		break;
227	default:
228		gctl_error(req, "Could not open lock (%d)", error);
229		break;
230	}
231	return;
232}
233
234static int
235g_bde_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp)
236{
237	struct g_consumer *cp;
238	struct g_provider *pp;
239	struct g_bde_softc *sc;
240
241	g_trace(G_T_TOPOLOGY, "g_bde_destroy_geom(%s, %s)", mp->name, gp->name);
242	g_topology_assert();
243	/*
244	 * Orderly detachment.
245	 */
246	KASSERT(gp != NULL, ("NULL geom"));
247	pp = LIST_FIRST(&gp->provider);
248	KASSERT(pp != NULL, ("NULL provider"));
249	if (pp->acr > 0 || pp->acw > 0 || pp->ace > 0)
250		return (EBUSY);
251	sc = gp->softc;
252	cp = LIST_FIRST(&gp->consumer);
253	KASSERT(cp != NULL, ("NULL consumer"));
254	sc->dead = 1;
255	wakeup(sc);
256	g_access(cp, -1, -1, -1);
257	g_detach(cp);
258	g_destroy_consumer(cp);
259	while (sc->dead != 2 && !LIST_EMPTY(&pp->consumers))
260		tsleep(sc, PRIBIO, "g_bdedie", hz);
261	mtx_destroy(&sc->worklist_mutex);
262	explicit_bzero(&sc->key, sizeof sc->key);
263	g_free(sc);
264	g_wither_geom(gp, ENXIO);
265	return (0);
266}
267
268static void
269g_bde_ctlreq(struct gctl_req *req, struct g_class *mp, char const *verb)
270{
271	struct g_geom *gp;
272	struct g_provider *pp;
273
274	if (!strcmp(verb, "create geom")) {
275		pp = gctl_get_provider(req, "provider");
276		if (pp != NULL)
277			g_bde_create_geom(req, mp, pp);
278	} else if (!strcmp(verb, "destroy geom")) {
279		gp = gctl_get_geom(req, mp, "geom");
280		if (gp != NULL)
281			g_bde_destroy_geom(req, mp, gp);
282	} else {
283		gctl_error(req, "unknown verb");
284	}
285}
286
287static struct g_class g_bde_class	= {
288	.name = BDE_CLASS_NAME,
289	.version = G_VERSION,
290	.destroy_geom = g_bde_destroy_geom,
291	.ctlreq = g_bde_ctlreq,
292	.start = g_bde_start,
293	.orphan = g_bde_orphan,
294	.access = g_bde_access,
295	.spoiled = g_std_spoiled,
296};
297
298DECLARE_GEOM_CLASS(g_bde_class, g_bde);
299MODULE_VERSION(geom_bde, 0);
300