Add Geom Based Disk Encryption to the tree.

This is an encryption module designed for to secure denial of access
to the contents of "cold disks" with or without destruction activation.

Major features:

   * Based on AES, MD5 and ARC4 algorithms.
   * Four cryptographic barriers:
        1) Pass-phrase encrypts the master key.
        2) Pass-phrase + Lock data locates master key.
        3) 128 bit key derived from 2048 bit master key protects sector key.
        3) 128 bit random single-use sector keys protect data payload.
   * Up to four different changeable pass-phrases.
   * Blackening feature for provable destruction of master key material.
   * Isotropic disk contents offers no information about sector contents.
   * Configurable destination sector range allows steganographic deployment.

This commit adds the kernel part, separate commits will follow for the
userland utility and documentation.

This software was developed for the FreeBSD Project by Poul-Henning Kamp and
NAI Labs, the Security Research Division of Network Associates, Inc.  under
DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
research program.

Many thanks to Robert Watson, CBOSS Principal Investigator for making this
possible.

Sponsored by:   DARPA & NAI Labs.

1 files changed, 282 insertions, 0 deletions

diff --git a/sys/geom/bde/g_bde.c b/sys/geom/bde/g_bde.c
new file mode 100644
index 000000000000..51fd77977004
--- /dev/null
+++ b/sys/geom/bde/g_bde.c
@@ -0,0 +1,282 @@
+/*-
+ * Copyright (c) 2002 Poul-Henning Kamp
+ * Copyright (c) 2002 Networks Associates Technology, Inc.
+ * All rights reserved.
+ *
+ * This software was developed for the FreeBSD Project by Poul-Henning Kamp
+ * and NAI Labs, the Security Research Division of Network Associates, Inc.
+ * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
+ * DARPA CHATS research program.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the authors may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ *
+ */
+
+#include <sys/param.h>
+#include <sys/stdint.h>
+#include <sys/bio.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/malloc.h>
+#include <geom/geom.h>
+#include <geom/bde/g_bde.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/kthread.h>
+
+#define BDE_CLASS_NAME "BDE"
+
+static void
+g_bde_start(struct bio *bp)
+{
+	struct g_geom *gp;
+	struct g_consumer *cp;
+	struct g_bde_softc *sc;
+
+	gp = bp->bio_to->geom;
+	cp = LIST_FIRST(&gp->consumer);
+	sc = gp->softc;
+	switch (bp->bio_cmd) {
+	case BIO_DELETE:
+	case BIO_READ:
+	case BIO_WRITE:
+		g_bde_start1(bp);
+		break;
+	case BIO_GETATTR:
+	case BIO_SETATTR:
+		if (g_handleattr_off_t(bp, "GEOM::mediasize", sc->mediasize))
+			return;
+		if (g_handleattr_int(bp, "GEOM::sectorsize", sc->sectorsize))
+			return;
+		g_io_deliver(bp, EOPNOTSUPP);
+		break;
+	default:
+		g_io_deliver(bp, EOPNOTSUPP);
+		return;
+	}
+	return;
+}
+
+static void
+g_bde_orphan(struct g_consumer *cp)
+{
+	struct g_geom *gp;
+	struct g_provider *pp;
+	struct g_bde_softc *sc;
+	int error;
+
+	g_trace(G_T_TOPOLOGY, "g_bde_orphan(%p/%s)", cp, cp->provider->name);
+	g_topology_assert();
+	KASSERT(cp->provider->error != 0,
+		("g_bde_orphan with error == 0"));
+
+	gp = cp->geom;
+	sc = gp->softc;
+	gp->flags |= G_GEOM_WITHER;
+	error = cp->provider->error;
+	LIST_FOREACH(pp, &gp->provider, provider)
+		g_orphan_provider(pp, error);
+	bzero(sc, sizeof(struct g_bde_softc));	/* destroy evidence */
+	return;
+}
+
+static int
+g_bde_access(struct g_provider *pp, int dr, int dw, int de)
+{
+	struct g_geom *gp;
+	struct g_consumer *cp;
+
+	gp = pp->geom;
+	cp = LIST_FIRST(&gp->consumer);
+	if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0) {
+		de++;
+		dr++;
+	}
+	/* ... and let go of it on last close */
+	if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1) {
+		de--;
+		dr--;
+	}
+	return (g_access_rel(cp, dr, dw, de));
+}
+
+static int
+g_bde_create(struct g_createargs *ga)
+{
+	struct g_geom *gp;
+	struct g_consumer *cp;
+	struct g_provider *pp;
+	struct g_bde_key *kp;
+	int error;
+	u_int sectorsize;
+	off_t mediasize;
+	struct g_bde_softc *sc;
+
+	g_trace(G_T_TOPOLOGY, "g_bde_create(%d)", ga->flag);
+	g_topology_assert();
+	if (ga->flag == 1) {
+		/*
+		 * Orderly dettachment.
+		 */
+		if (ga->geom != NULL) {
+			gp = ga->geom;
+		} else if (ga->provider != NULL) {
+			if (ga->provider->geom->class == ga->class) {
+				gp = ga->provider->geom;
+			} else {
+				LIST_FOREACH(cp, &ga->provider->consumers,
+				    consumers) {
+					if (cp->geom->class == ga->class) {
+						gp = cp->geom;
+						break;
+					}
+				}
+			}
+			if (gp == NULL)
+				return (EINVAL);
+		} else {
+			return (EINVAL);
+		}
+		KASSERT(gp != NULL, ("NULL geom"));
+		pp = LIST_FIRST(&gp->provider);
+		KASSERT(pp != NULL, ("NULL provider"));
+		if (pp->acr > 0 || pp->acw > 0 || pp->ace > 0)
+			return (EBUSY);
+		g_orphan_provider(pp, ENXIO);
+		sc = gp->softc;
+		cp = LIST_FIRST(&gp->consumer);
+		KASSERT(cp != NULL, ("NULL consumer"));
+		sc->dead = 1;
+		wakeup(sc);
+		error = g_access_rel(cp, -1, -1, -1);
+		KASSERT(error == 0, ("error on close"));
+		g_detach(cp);
+		g_destroy_consumer(cp);
+		g_topology_unlock();
+		while (sc->dead != 2 && !LIST_EMPTY(&pp->consumers))
+			tsleep(sc, PRIBIO, "g_bdedie", hz);
+		g_topology_lock();
+		g_destroy_provider(pp);
+		mtx_destroy(&sc->worklist_mutex);
+		bzero(&sc->key, sizeof sc->key);
+		g_free(sc);
+		g_destroy_geom(gp);
+		return (0);
+	}
+
+	if (ga->flag != 0)
+		return (EOPNOTSUPP);
+
+	if (ga->provider == NULL)
+		return (EINVAL);
+	/*
+	 * Attach
+	 */
+	gp = g_new_geomf(ga->class, "%s.bde", ga->provider->name);
+	gp->start = g_bde_start;
+	gp->orphan = g_bde_orphan;
+	gp->access = g_bde_access;
+	gp->spoiled = g_std_spoiled;
+	cp = g_new_consumer(gp);
+	g_attach(cp, ga->provider);
+	error = g_access_rel(cp, 1, 1, 1);
+	if (error) {
+		g_detach(cp);
+		g_destroy_consumer(cp);
+		g_destroy_geom(gp);
+		return (error);
+	}
+	g_topology_unlock();
+	while (1) {
+		error = g_getattr("GEOM::sectorsize", cp, &sectorsize);
+		if (error)
+			break;
+		error = g_getattr("GEOM::mediasize", cp, &mediasize);
+		if (error)
+			break;
+		sc = g_malloc(sizeof(struct g_bde_softc), M_WAITOK | M_ZERO);
+		gp->softc = sc;
+		sc->geom = gp;
+		sc->consumer = cp;
+
+		error = g_bde_decrypt_lock(sc, ga->ptr,
+		    (u_char *)ga->ptr + 256, mediasize, sectorsize, NULL);
+		bzero(sc->arc4_sbox, sizeof sc->arc4_sbox);
+		if (error)
+			break;
+		kp = &sc->key;
+
+		/* Initialize helper-fields */
+		kp->keys_per_sector = kp->sectorsize / G_BDE_SKEYLEN;
+		kp->zone_cont = kp->keys_per_sector * kp->sectorsize;
+		kp->zone_width = kp->zone_cont + kp->sectorsize;
+		kp->media_width = kp->sectorN - kp->sector0 -
+		    G_BDE_MAXKEYS * kp->sectorsize;
+
+		/* Our external parameters */
+		sc->zone_cont = kp->zone_cont;
+		sc->mediasize = g_bde_max_sector(kp);
+		sc->sectorsize = kp->sectorsize;
+
+		TAILQ_INIT(&sc->freelist);
+		TAILQ_INIT(&sc->worklist);
+		mtx_init(&sc->worklist_mutex, "g_bde_worklist", NULL, MTX_DEF);
+		mtx_lock(&Giant);
+		/* XXX: error check */
+		kthread_create(g_bde_worker, gp, &sc->thread, 0, 0,
+			"g_bde %s", gp->name);
+		mtx_unlock(&Giant);
+		g_topology_lock();
+		pp = g_new_providerf(gp, gp->name);
+		pp->mediasize = sc->mediasize;
+		g_error_provider(pp, 0);
+		g_topology_unlock();
+		break;
+	}
+	g_topology_lock();
+	if (error == 0) {
+		ga->geom = gp;
+		return (0);
+	} else {
+		g_access_rel(cp, -1, -1, -1);
+	}
+	g_detach(cp);
+	g_destroy_consumer(cp);
+	if (gp->softc != NULL)
+		g_free(gp->softc);
+	g_destroy_geom(gp);
+	return (error);
+}
+
+static struct g_class g_bde_class	= {
+	BDE_CLASS_NAME,
+	NULL,
+	g_bde_create,
+	G_CLASS_INITIALIZER
+};
+
+DECLARE_GEOM_CLASS(g_bde_class, g_bde);