geom_aes.c revision 98987
197318Sphk/*- 297318Sphk * Copyright (c) 2002 Poul-Henning Kamp 397318Sphk * Copyright (c) 2002 Networks Associates Technology, Inc. 497318Sphk * All rights reserved. 597318Sphk * 697318Sphk * This software was developed for the FreeBSD Project by Poul-Henning Kamp 797318Sphk * and NAI Labs, the Security Research Division of Network Associates, Inc. 897318Sphk * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 997318Sphk * DARPA CHATS research program. 1097318Sphk * 1197318Sphk * Redistribution and use in source and binary forms, with or without 1297318Sphk * modification, are permitted provided that the following conditions 1397318Sphk * are met: 1497318Sphk * 1. Redistributions of source code must retain the above copyright 1597318Sphk * notice, this list of conditions and the following disclaimer. 1697318Sphk * 2. Redistributions in binary form must reproduce the above copyright 1797318Sphk * notice, this list of conditions and the following disclaimer in the 1897318Sphk * documentation and/or other materials provided with the distribution. 1997318Sphk * 3. The names of the authors may not be used to endorse or promote 2097318Sphk * products derived from this software without specific prior written 2197318Sphk * permission. 2297318Sphk * 2397318Sphk * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 2497318Sphk * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2597318Sphk * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2697318Sphk * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 2797318Sphk * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2897318Sphk * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2997318Sphk * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 3097318Sphk * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 3197318Sphk * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3297318Sphk * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3397318Sphk * SUCH DAMAGE. 3497318Sphk * 3597318Sphk * $FreeBSD: head/sys/geom/geom_aes.c 98987 2002-06-28 21:25:15Z phk $ 3697318Sphk * 3797318Sphk * This method provides AES encryption with a compiled in key (default 3897318Sphk * all zeroes). 3997318Sphk * 4097318Sphk * XXX: This could probably save a lot of code by pretending to be a slicer. 4197318Sphk */ 4297318Sphk 4397318Sphk#include <sys/param.h> 4497318Sphk#ifndef _KERNEL 4597318Sphk#include <stdio.h> 4697318Sphk#include <string.h> 4797318Sphk#include <stdlib.h> 4897318Sphk#include <signal.h> 4997318Sphk#include <err.h> 5097318Sphk#else 5197318Sphk#include <sys/systm.h> 5297318Sphk#include <sys/kernel.h> 5397318Sphk#include <sys/conf.h> 5497318Sphk#include <sys/bio.h> 5597318Sphk#include <sys/malloc.h> 5697318Sphk#include <sys/lock.h> 5797318Sphk#include <sys/mutex.h> 5898987Sphk#include <sys/libkern.h> 5998987Sphk#include <sys/md5.h> 6098987Sphk#include <sys/endian.h> 6197318Sphk#endif 6297318Sphk#include <sys/errno.h> 6397318Sphk#include <geom/geom.h> 6497318Sphk 6597318Sphk#include <crypto/rijndael/rijndael.h> 6697318Sphk 6797318Sphk#include <crypto/rijndael/rijndael.h> 6897318Sphk 6997318Sphk#define AES_CLASS_NAME "AES" 7097318Sphk 7198987Sphk#define MASTER_KEY_LENGTH (1024/8) 7298987Sphk 7397318Sphkstatic u_char *aes_magic = "<<FreeBSD-GEOM-AES>>"; 7498987Sphkstatic u_char *aes_magic_random = "<<FreeBSD-GEOM-AES-RANDOM>>"; 7598987Sphkstatic u_char *aes_magic_test = "<<FreeBSD-GEOM-AES-TEST>>"; 7697318Sphk 7797318Sphk 7897318Sphkstruct g_aes_softc { 7998987Sphk enum { 8098987Sphk KEY_ZERO, 8198987Sphk KEY_RANDOM, 8298987Sphk KEY_TEST 8398987Sphk } keying; 8497318Sphk u_int sectorsize; 8597318Sphk off_t mediasize; 8697318Sphk cipherInstance ci; 8798987Sphk u_char master_key[MASTER_KEY_LENGTH]; 8897318Sphk}; 8997318Sphk 9098987Sphk/* 9198987Sphk * Generate a sectorkey from the masterkey and the offset position. 9298987Sphk * 9398987Sphk * For KEY_ZERO we just return a key of all zeros. 9498987Sphk * 9598987Sphk * We feed the sector byte offset, 16 bytes of the master-key and 9698987Sphk * the sector byte offset once more to MD5. 9798987Sphk * The sector byte offset is converted to little-endian format first 9898987Sphk * to support multi-architecture operation. 9998987Sphk * We use 16 bytes from the master-key starting at the logical sector 10098987Sphk * number modulus he length of the master-key. If need be we wrap 10198987Sphk * around to the start of the master-key. 10298987Sphk */ 10398987Sphk 10497318Sphkstatic void 10598987Sphkg_aes_makekey(struct g_aes_softc *sc, off_t off, keyInstance *ki, int dir) 10698987Sphk{ 10798987Sphk MD5_CTX cx; 10898987Sphk u_int64_t u64; 10998987Sphk u_int u, u1; 11098987Sphk u_char *p, buf[16]; 11198987Sphk 11298987Sphk if (sc->keying == KEY_ZERO) { 11398987Sphk rijndael_makeKey(ki, dir, 128, sc->master_key); 11498987Sphk return; 11598987Sphk } 11698987Sphk MD5Init(&cx); 11798987Sphk u64 = htole64(off); 11898987Sphk MD5Update(&cx, (u_char *)&u64, sizeof(u64)); 11998987Sphk u = off / sc->sectorsize; 12098987Sphk u %= sizeof sc->master_key; 12198987Sphk p = sc->master_key + u; 12298987Sphk if (u + 16 <= sizeof(sc->master_key)) { 12398987Sphk MD5Update(&cx, p, 16); 12498987Sphk } else { 12598987Sphk u1 = sizeof sc->master_key - u; 12698987Sphk MD5Update(&cx, p, u1); 12798987Sphk MD5Update(&cx, sc->master_key, 16 - u1); 12898987Sphk u1 = 0; /* destroy evidence */ 12998987Sphk } 13098987Sphk u = 0; /* destroy evidence */ 13198987Sphk MD5Update(&cx, (u_char *)&u64, sizeof(u64)); 13298987Sphk u64 = 0; /* destroy evidence */ 13398987Sphk MD5Final(buf, &cx); 13498987Sphk bzero(&cx, sizeof cx); /* destroy evidence */ 13598987Sphk rijndael_makeKey(ki, dir, 128, buf); 13698987Sphk bzero(buf, sizeof buf); /* destroy evidence */ 13798987Sphk 13898987Sphk} 13998987Sphk 14098987Sphkstatic void 14197318Sphkg_aes_read_done(struct bio *bp) 14297318Sphk{ 14397318Sphk struct g_geom *gp; 14497318Sphk struct g_aes_softc *sc; 14597318Sphk u_char *p, *b, *e, *sb; 14698987Sphk keyInstance dkey; 14798987Sphk off_t o; 14897318Sphk 14997318Sphk gp = bp->bio_from->geom; 15097318Sphk sc = gp->softc; 15197318Sphk sb = g_malloc(sc->sectorsize, M_WAITOK); 15297318Sphk b = bp->bio_data; 15397318Sphk e = bp->bio_data; 15497318Sphk e += bp->bio_length; 15598987Sphk o = bp->bio_offset - sc->sectorsize; 15697318Sphk for (p = b; p < e; p += sc->sectorsize) { 15798987Sphk g_aes_makekey(sc, o, &dkey, DIR_DECRYPT); 15898987Sphk rijndael_blockDecrypt(&sc->ci, &dkey, p, sc->sectorsize * 8, sb); 15997318Sphk bcopy(sb, p, sc->sectorsize); 16098987Sphk o += sc->sectorsize; 16197318Sphk } 16298987Sphk bzero(&dkey, sizeof dkey); /* destroy evidence */ 16398987Sphk bzero(sb, sc->sectorsize); /* destroy evidence */ 16498987Sphk g_free(sb); 16597318Sphk g_std_done(bp); 16697318Sphk} 16797318Sphk 16897318Sphkstatic void 16997318Sphkg_aes_write_done(struct bio *bp) 17097318Sphk{ 17198987Sphk struct g_aes_softc *sc; 17298987Sphk struct g_geom *gp; 17397318Sphk 17498987Sphk gp = bp->bio_to->geom; 17598987Sphk sc = gp->softc; 17698987Sphk bzero(bp->bio_data, bp->bio_length); /* destroy evidence */ 17797318Sphk g_free(bp->bio_data); 17897318Sphk g_std_done(bp); 17997318Sphk} 18097318Sphk 18197318Sphkstatic void 18297318Sphkg_aes_start(struct bio *bp) 18397318Sphk{ 18497318Sphk struct g_geom *gp; 18597318Sphk struct g_consumer *cp; 18697318Sphk struct g_aes_softc *sc; 18797318Sphk struct bio *bp2; 18897318Sphk u_char *p1, *p2, *b, *e; 18998987Sphk keyInstance ekey; 19098987Sphk off_t o; 19197318Sphk 19297318Sphk gp = bp->bio_to->geom; 19397318Sphk cp = LIST_FIRST(&gp->consumer); 19497318Sphk sc = gp->softc; 19597318Sphk switch (bp->bio_cmd) { 19697318Sphk case BIO_READ: 19797318Sphk bp2 = g_clone_bio(bp); 19897318Sphk bp2->bio_done = g_aes_read_done; 19997318Sphk bp2->bio_offset += sc->sectorsize; 20097318Sphk g_io_request(bp2, cp); 20197318Sphk break; 20297318Sphk case BIO_WRITE: 20397318Sphk bp2 = g_clone_bio(bp); 20497318Sphk bp2->bio_done = g_aes_write_done; 20597318Sphk bp2->bio_offset += sc->sectorsize; 20697318Sphk bp2->bio_data = g_malloc(bp->bio_length, M_WAITOK); 20797318Sphk b = bp->bio_data; 20897318Sphk e = bp->bio_data; 20997318Sphk e += bp->bio_length; 21097318Sphk p2 = bp2->bio_data; 21198987Sphk o = bp->bio_offset; 21297318Sphk for (p1 = b; p1 < e; p1 += sc->sectorsize) { 21398987Sphk g_aes_makekey(sc, o, &ekey, DIR_ENCRYPT); 21498987Sphk rijndael_blockEncrypt(&sc->ci, &ekey, 21597318Sphk p1, sc->sectorsize * 8, p2); 21697318Sphk p2 += sc->sectorsize; 21798987Sphk o += sc->sectorsize; 21897318Sphk } 21998987Sphk bzero(&ekey, sizeof ekey); /* destroy evidence */ 22097318Sphk g_io_request(bp2, cp); 22197318Sphk break; 22297318Sphk case BIO_GETATTR: 22397318Sphk case BIO_SETATTR: 22498066Sphk if (g_handleattr_off_t(bp, "GEOM::mediasize", sc->mediasize)) 22597318Sphk return; 22698066Sphk if (g_handleattr_int(bp, "GEOM::sectorsize", sc->sectorsize)) 22797318Sphk return; 22897318Sphk bp2 = g_clone_bio(bp); 22997318Sphk bp2->bio_done = g_std_done; 23097318Sphk bp2->bio_offset += sc->sectorsize; 23197318Sphk g_io_request(bp2, cp); 23297318Sphk break; 23397318Sphk default: 23497318Sphk bp->bio_error = EOPNOTSUPP; 23597318Sphk g_io_deliver(bp); 23697318Sphk return; 23797318Sphk } 23897318Sphk return; 23997318Sphk} 24097318Sphk 24197318Sphkstatic void 24297318Sphkg_aes_orphan(struct g_consumer *cp) 24397318Sphk{ 24497318Sphk struct g_geom *gp; 24597318Sphk struct g_provider *pp; 24698987Sphk struct g_aes_softc *sc; 24797318Sphk int error; 24897318Sphk 24997318Sphk g_trace(G_T_TOPOLOGY, "g_aes_orphan(%p/%s)", cp, cp->provider->name); 25097318Sphk g_topology_assert(); 25197318Sphk KASSERT(cp->provider->error != 0, 25297318Sphk ("g_aes_orphan with error == 0")); 25397318Sphk 25497318Sphk gp = cp->geom; 25598987Sphk sc = gp->softc; 25697318Sphk gp->flags |= G_GEOM_WITHER; 25797318Sphk error = cp->provider->error; 25897318Sphk LIST_FOREACH(pp, &gp->provider, provider) 25997318Sphk g_orphan_provider(pp, error); 26098987Sphk bzero(sc, sizeof(struct g_aes_softc)); /* destroy evidence */ 26197318Sphk return; 26297318Sphk} 26397318Sphk 26497318Sphkstatic int 26597318Sphkg_aes_access(struct g_provider *pp, int dr, int dw, int de) 26697318Sphk{ 26797318Sphk struct g_geom *gp; 26897318Sphk struct g_consumer *cp; 26997318Sphk 27097318Sphk gp = pp->geom; 27197318Sphk cp = LIST_FIRST(&gp->consumer); 27297318Sphk /* On first open, grab an extra "exclusive" bit */ 27397318Sphk if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0) 27497318Sphk de++; 27597318Sphk /* ... and let go of it on last close */ 27697318Sphk if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1) 27797318Sphk de--; 27897318Sphk return (g_access_rel(cp, dr, dw, de)); 27997318Sphk} 28097318Sphk 28197318Sphkstatic struct g_geom * 28297318Sphkg_aes_taste(struct g_class *mp, struct g_provider *pp, int flags __unused) 28397318Sphk{ 28497318Sphk struct g_geom *gp; 28597318Sphk struct g_consumer *cp; 28697318Sphk struct g_aes_softc *sc; 28797318Sphk int error; 28897318Sphk u_int sectorsize; 28997318Sphk off_t mediasize; 29097318Sphk u_char *buf; 29197318Sphk 29297318Sphk g_trace(G_T_TOPOLOGY, "aes_taste(%s,%s)", mp->name, pp->name); 29397318Sphk g_topology_assert(); 29497318Sphk gp = g_new_geomf(mp, "%s.aes", pp->name); 29597318Sphk gp->start = g_aes_start; 29697318Sphk gp->orphan = g_aes_orphan; 29797318Sphk gp->spoiled = g_std_spoiled; 29897318Sphk cp = g_new_consumer(gp); 29997318Sphk g_attach(cp, pp); 30097318Sphk error = g_access_rel(cp, 1, 0, 0); 30197318Sphk if (error) { 30298066Sphk g_detach(cp); 30397318Sphk g_destroy_consumer(cp); 30497318Sphk g_destroy_geom(gp); 30597318Sphk return (NULL); 30697318Sphk } 30797318Sphk buf = NULL; 30897318Sphk while (1) { 30997318Sphk if (gp->rank != 2) 31097318Sphk break; 31197318Sphk error = g_getattr("GEOM::sectorsize", cp, §orsize); 31297318Sphk if (error) 31397318Sphk break; 31497318Sphk error = g_getattr("GEOM::mediasize", cp, &mediasize); 31597318Sphk if (error) 31697318Sphk break; 31797318Sphk buf = g_read_data(cp, 0, sectorsize, &error); 31897318Sphk if (buf == NULL || error != 0) { 31997318Sphk break; 32097318Sphk } 32198987Sphk sc = g_malloc(sizeof(struct g_aes_softc), M_WAITOK | M_ZERO); 32298987Sphk if (!memcmp(buf, aes_magic, strlen(aes_magic))) { 32398987Sphk sc->keying = KEY_ZERO; 32498987Sphk } else if (!memcmp(buf, aes_magic_random, 32598987Sphk strlen(aes_magic_random))) { 32698987Sphk sc->keying = KEY_RANDOM; 32798987Sphk } else if (!memcmp(buf, aes_magic_test, 32898987Sphk strlen(aes_magic_test))) { 32998987Sphk sc->keying = KEY_TEST; 33098987Sphk } else { 33198987Sphk g_free(sc); 33297318Sphk break; 33398987Sphk } 33497318Sphk gp->softc = sc; 33597318Sphk gp->access = g_aes_access; 33697318Sphk sc->sectorsize = sectorsize; 33797318Sphk sc->mediasize = mediasize - sectorsize; 33897318Sphk rijndael_cipherInit(&sc->ci, MODE_CBC, NULL); 33998987Sphk if (sc->keying == KEY_TEST) { 34098987Sphk int i; 34198987Sphk u_char *p; 34298987Sphk 34398987Sphk p = sc->master_key; 34498987Sphk for (i = 0; i < sizeof sc->master_key; i ++) 34598987Sphk *p++ = i; 34698987Sphk } 34798987Sphk if (sc->keying == KEY_RANDOM) { 34898987Sphk int i; 34998987Sphk u_int32_t u; 35098987Sphk u_char *p; 35198987Sphk 35298987Sphk p = sc->master_key; 35398987Sphk for (i = 0; i < sizeof sc->master_key; i += sizeof u) { 35498987Sphk u = arc4random(); 35598987Sphk *p++ = u; 35698987Sphk *p++ = u >> 8; 35798987Sphk *p++ = u >> 16; 35898987Sphk *p++ = u >> 24; 35998987Sphk } 36098987Sphk } 36197318Sphk pp = g_new_providerf(gp, gp->name); 36297318Sphk pp->mediasize = mediasize - sectorsize; 36397318Sphk g_error_provider(pp, 0); 36497318Sphk break; 36597318Sphk } 36697318Sphk if (buf) 36797318Sphk g_free(buf); 36897318Sphk g_access_rel(cp, -1, 0, 0); 36997318Sphk if (gp->softc != NULL) 37097318Sphk return (gp); 37198066Sphk g_detach(cp); 37297318Sphk g_destroy_consumer(cp); 37397318Sphk g_destroy_geom(gp); 37497318Sphk return (NULL); 37597318Sphk} 37697318Sphk 37797318Sphkstatic struct g_class g_aes_class = { 37897318Sphk AES_CLASS_NAME, 37997318Sphk g_aes_taste, 38097318Sphk NULL, 38198066Sphk G_CLASS_INITIALIZER 38297318Sphk}; 38397318Sphk 38497318SphkDECLARE_GEOM_CLASS(g_aes_class, g_aes); 385