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|
/* $NetBSD: cgd.c,v 1.13 2004/01/10 14:39:50 yamt Exp $ */
/*-
* Copyright (c) 2002 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Roland C. Dowdeswell.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.13 2004/01/10 14:39:50 yamt Exp $");
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/errno.h>
#include <sys/buf.h>
#include <sys/malloc.h>
#include <sys/pool.h>
#include <sys/ioctl.h>
#include <sys/device.h>
#include <sys/disk.h>
#include <sys/disklabel.h>
#include <sys/fcntl.h>
#include <sys/vnode.h>
#include <sys/lock.h>
#include <sys/conf.h>
#include <dev/dkvar.h>
#include <dev/cgdvar.h>
/* Entry Point Functions */
void cgdattach(int);
dev_type_open(cgdopen);
dev_type_close(cgdclose);
dev_type_read(cgdread);
dev_type_write(cgdwrite);
dev_type_ioctl(cgdioctl);
dev_type_strategy(cgdstrategy);
dev_type_dump(cgddump);
dev_type_size(cgdsize);
const struct bdevsw cgd_bdevsw = {
cgdopen, cgdclose, cgdstrategy, cgdioctl,
cgddump, cgdsize, D_DISK
};
const struct cdevsw cgd_cdevsw = {
cgdopen, cgdclose, cgdread, cgdwrite, cgdioctl,
nostop, notty, nopoll, nommap, nokqfilter, D_DISK
};
/* Internal Functions */
static void cgdstart(struct dk_softc *, struct buf *);
static void cgdiodone(struct buf *);
static int cgd_ioctl_set(struct cgd_softc *, void *, struct proc *);
static int cgd_ioctl_clr(struct cgd_softc *, void *, struct proc *);
static int cgdinit(struct cgd_softc *, char *, struct vnode *,
struct proc *);
static void cgd_cipher(struct cgd_softc *, caddr_t, caddr_t,
size_t, daddr_t, size_t, int);
/* Pseudo-disk Interface */
static struct dk_intf the_dkintf = {
DTYPE_CGD,
"cgd",
cgdopen,
cgdclose,
cgdstrategy,
cgdstart,
};
static struct dk_intf *di = &the_dkintf;
/* DIAGNOSTIC and DEBUG definitions */
#if defined(CGDDEBUG) && !defined(DEBUG)
#define DEBUG
#endif
#ifdef DEBUG
int cgddebug = 0;
#define CGDB_FOLLOW 0x1
#define CGDB_IO 0x2
#define CGDB_CRYPTO 0x4
#define IFDEBUG(x,y) if (cgddebug & (x)) y
#define DPRINTF(x,y) IFDEBUG(x, printf y)
#define DPRINTF_FOLLOW(y) DPRINTF(CGDB_FOLLOW, y)
static void hexprint(char *, void *, int);
#else
#define IFDEBUG(x,y)
#define DPRINTF(x,y)
#define DPRINTF_FOLLOW(y)
#endif
#ifdef DIAGNOSTIC
#define DIAGPANIC(x) panic x
#define DIAGCONDPANIC(x,y) if (x) panic y
#else
#define DIAGPANIC(x)
#define DIAGCONDPANIC(x,y)
#endif
/* Component Buffer Pool structures and macros */
struct cgdbuf {
struct buf cb_buf; /* new I/O buf */
struct buf *cb_obp; /* ptr. to original I/O buf */
struct cgd_softc *cb_sc; /* pointer to cgd softc */
};
struct pool cgd_cbufpool;
#define CGD_GETBUF() pool_get(&cgd_cbufpool, PR_NOWAIT)
#define CGD_PUTBUF(cbp) pool_put(&cgd_cbufpool, cbp)
/* Global variables */
struct cgd_softc *cgd_softc;
int numcgd = 0;
/* Utility Functions */
#define CGDUNIT(x) DISKUNIT(x)
#define GETCGD_SOFTC(_cs, x) if (!((_cs) = getcgd_softc(x))) return ENXIO
static struct cgd_softc *
getcgd_softc(dev_t dev)
{
int unit = CGDUNIT(dev);
DPRINTF_FOLLOW(("getcgd_softc(0x%x): unit = %d\n", dev, unit));
if (unit >= numcgd)
return NULL;
return &cgd_softc[unit];
}
/* The code */
static void
cgdsoftc_init(struct cgd_softc *cs, int num)
{
char buf[DK_XNAME_SIZE];
memset(cs, 0x0, sizeof(*cs));
snprintf(buf, DK_XNAME_SIZE, "cgd%d", num);
dk_sc_init(&cs->sc_dksc, cs, buf);
}
void
cgdattach(int num)
{
int i;
DPRINTF_FOLLOW(("cgdattach(%d)\n", num));
if (num <= 0) {
DIAGPANIC(("cgdattach: count <= 0"));
return;
}
cgd_softc = (void *)malloc(num * sizeof(*cgd_softc), M_DEVBUF, M_NOWAIT);
if (!cgd_softc) {
printf("WARNING: unable to malloc(9) memory for crypt disks\n");
DIAGPANIC(("cgdattach: cannot malloc(9) enough memory"));
return;
}
numcgd = num;
for (i=0; i<num; i++)
cgdsoftc_init(&cgd_softc[i], i);
/* Init component buffer pool. XXX, can we put this in dksubr.c? */
pool_init(&cgd_cbufpool, sizeof(struct cgdbuf), 0, 0, 0,
"cgdpl", NULL);
}
int
cgdopen(dev_t dev, int flags, int fmt, struct proc *p)
{
struct cgd_softc *cs;
DPRINTF_FOLLOW(("cgdopen(%d, %d)\n", dev, flags));
GETCGD_SOFTC(cs, dev);
return dk_open(di, &cs->sc_dksc, dev, flags, fmt, p);
}
int
cgdclose(dev_t dev, int flags, int fmt, struct proc *p)
{
struct cgd_softc *cs;
DPRINTF_FOLLOW(("cgdclose(%d, %d)\n", dev, flags));
GETCGD_SOFTC(cs, dev);
return dk_close(di, &cs->sc_dksc, dev, flags, fmt, p);
}
void
cgdstrategy(struct buf *bp)
{
struct cgd_softc *cs = getcgd_softc(bp->b_dev);
DPRINTF_FOLLOW(("cgdstrategy(%p): b_bcount = %ld\n", bp,
(long)bp->b_bcount));
/* XXXrcd: Should we test for (cs != NULL)? */
dk_strategy(di, &cs->sc_dksc, bp);
return;
}
int
cgdsize(dev_t dev)
{
struct cgd_softc *cs = getcgd_softc(dev);
DPRINTF_FOLLOW(("cgdsize(%d)\n", dev));
if (!cs)
return -1;
return dk_size(di, &cs->sc_dksc, dev);
}
static void
cgdstart(struct dk_softc *dksc, struct buf *bp)
{
struct cgd_softc *cs = dksc->sc_osc;
struct cgdbuf *cbp;
struct partition *pp;
caddr_t addr;
caddr_t newaddr;
daddr_t bn;
DPRINTF_FOLLOW(("cgdstart(%p, %p)\n", dksc, bp));
disk_busy(&dksc->sc_dkdev); /* XXX: put in dksubr.c */
/* XXXrcd:
* Translate partition relative blocks to absolute blocks,
* this probably belongs (somehow) in dksubr.c, since it
* is independant of the underlying code... This will require
* that the interface be expanded slightly, though.
*/
bn = bp->b_blkno;
if (DISKPART(bp->b_dev) != RAW_PART) {
pp = &cs->sc_dksc.sc_dkdev.dk_label->d_partitions[DISKPART(bp->b_dev)];
bn += pp->p_offset;
}
/*
* If we are writing, then we need to encrypt the outgoing
* block. In the best case scenario, we are able to allocate
* enough memory to encrypt the data in a new block, otherwise
* we encrypt it in place (noting we'll have to decrypt it after
* the write.)
*/
newaddr = addr = bp->b_data;
if ((bp->b_flags & B_READ) == 0) {
newaddr = malloc(bp->b_bcount, M_DEVBUF, 0);
if (!newaddr)
newaddr = addr;
cgd_cipher(cs, newaddr, addr, bp->b_bcount, bn,
DEV_BSIZE, CGD_CIPHER_ENCRYPT);
}
cbp = CGD_GETBUF();
if (cbp == NULL) {
bp->b_error = ENOMEM;
bp->b_flags |= B_ERROR;
if (newaddr != addr)
free(newaddr, M_DEVBUF);
biodone(bp);
disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ));
return;
}
BUF_INIT(&cbp->cb_buf);
cbp->cb_buf.b_data = newaddr;
cbp->cb_buf.b_flags = bp->b_flags | B_CALL;
cbp->cb_buf.b_iodone = cgdiodone;
cbp->cb_buf.b_proc = bp->b_proc;
cbp->cb_buf.b_dev = cs->sc_tdev;
cbp->cb_buf.b_blkno = bn;
cbp->cb_buf.b_vp = cs->sc_tvn;
cbp->cb_buf.b_bcount = bp->b_bcount;
/* context for cgdiodone */
cbp->cb_obp = bp;
cbp->cb_sc = cs;
BIO_COPYPRIO(&cbp->cb_buf, bp);
if ((cbp->cb_buf.b_flags & B_READ) == 0)
cbp->cb_buf.b_vp->v_numoutput++;
VOP_STRATEGY(&cbp->cb_buf);
}
void
cgdiodone(struct buf *vbp)
{
struct cgdbuf *cbp = (struct cgdbuf *)vbp;
struct buf *obp = cbp->cb_obp;
struct buf *nbp = &cbp->cb_buf;
struct cgd_softc *cs = cbp->cb_sc;
struct dk_softc *dksc = &cs->sc_dksc;
int s;
DPRINTF_FOLLOW(("cgdiodone(%p)\n", vbp));
DPRINTF(CGDB_IO, ("cgdiodone: bp %p bcount %ld resid %ld\n",
obp, obp->b_bcount, obp->b_resid));
DPRINTF(CGDB_IO, (" dev 0x%x, cbp %p bn %" PRId64 " addr %p bcnt %ld\n",
cbp->cb_buf.b_dev, cbp, cbp->cb_buf.b_blkno, cbp->cb_buf.b_data,
cbp->cb_buf.b_bcount));
s = splbio();
if (nbp->b_flags & B_ERROR) {
obp->b_flags |= B_ERROR;
obp->b_error = nbp->b_error ? nbp->b_error : EIO;
printf("%s: error %d\n", dksc->sc_xname, obp->b_error);
}
/* Perform the decryption if we need to:
* o if we are reading, or
* o we wrote and couldn't allocate memory.
*
* Note: use the blocknumber from nbp, since it is what
* we used to encrypt the blocks.
*/
if (nbp->b_flags & B_READ || nbp->b_data == obp->b_data)
cgd_cipher(cs, obp->b_data, obp->b_data, obp->b_bcount,
nbp->b_blkno, DEV_BSIZE, CGD_CIPHER_DECRYPT);
/* If we managed to allocate memory, free it now... */
if (nbp->b_data != obp->b_data)
free(nbp->b_data, M_DEVBUF);
CGD_PUTBUF(cbp);
/* Request is complete for whatever reason */
obp->b_resid = 0;
if (obp->b_flags & B_ERROR)
obp->b_resid = obp->b_bcount;
disk_unbusy(&dksc->sc_dkdev, obp->b_bcount - obp->b_resid,
(obp->b_flags & B_READ));
biodone(obp);
splx(s);
}
/* XXX: we should probably put these into dksubr.c, mostly */
int
cgdread(dev_t dev, struct uio *uio, int flags)
{
struct cgd_softc *cs;
struct dk_softc *dksc;
DPRINTF_FOLLOW(("cgdread(%d, %p, %d)\n", dev, uio, flags));
GETCGD_SOFTC(cs, dev);
dksc = &cs->sc_dksc;
if ((dksc->sc_flags & DKF_INITED) == 0)
return ENXIO;
/* XXX see the comments about minphys in ccd.c */
return physio(cgdstrategy, NULL, dev, B_READ, minphys, uio);
}
/* XXX: we should probably put these into dksubr.c, mostly */
int
cgdwrite(dev_t dev, struct uio *uio, int flags)
{
struct cgd_softc *cs;
struct dk_softc *dksc;
DPRINTF_FOLLOW(("cgdwrite(%d, %p, %d)\n", dev, uio, flags));
GETCGD_SOFTC(cs, dev);
dksc = &cs->sc_dksc;
if ((dksc->sc_flags & DKF_INITED) == 0)
return ENXIO;
/* XXX see the comments about minphys in ccd.c */
return physio(cgdstrategy, NULL, dev, B_WRITE, minphys, uio);
}
int
cgdioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
{
struct cgd_softc *cs;
struct dk_softc *dksc;
int ret;
int part = DISKPART(dev);
int pmask = 1 << part;
DPRINTF_FOLLOW(("cgdioctl(%d, %ld, %p, %d, %p)\n",
dev, cmd, data, flag, p));
GETCGD_SOFTC(cs, dev);
dksc = &cs->sc_dksc;
switch (cmd) {
case CGDIOCSET:
case CGDIOCCLR:
if ((flag & FWRITE) == 0)
return EBADF;
}
if ((ret = lockmgr(&dksc->sc_lock, LK_EXCLUSIVE, NULL)) != 0)
return ret;
switch (cmd) {
case CGDIOCSET:
if (dksc->sc_flags & DKF_INITED)
ret = EBUSY;
else
ret = cgd_ioctl_set(cs, data, p);
break;
case CGDIOCCLR:
if (!(dksc->sc_flags & DKF_INITED)) {
ret = ENXIO;
break;
}
if (DK_BUSY(&cs->sc_dksc, pmask)) {
ret = EBUSY;
break;
}
ret = cgd_ioctl_clr(cs, data, p);
break;
default:
ret = dk_ioctl(di, dksc, dev, cmd, data, flag, p);
break;
}
lockmgr(&dksc->sc_lock, LK_RELEASE, NULL);
return ret;
}
int
cgddump(dev_t dev, daddr_t blkno, caddr_t va, size_t size)
{
struct cgd_softc *cs;
DPRINTF_FOLLOW(("cgddump(%d, %" PRId64 ", %p, %lu)\n", dev, blkno, va,
(unsigned long)size));
GETCGD_SOFTC(cs, dev);
return dk_dump(di, &cs->sc_dksc, dev, blkno, va, size);
}
/*
* XXXrcd:
* for now we hardcode the maximum key length.
*/
#define MAX_KEYSIZE 1024
/* ARGSUSED */
static int
cgd_ioctl_set(struct cgd_softc *cs, void *data, struct proc *p)
{
struct cgd_ioctl *ci = data;
struct vnode *vp;
int ret;
char *cp;
char inbuf[MAX_KEYSIZE];
cp = ci->ci_disk;
if ((ret = dk_lookup(cp, p, &vp)) != 0)
return ret;
if ((ret = cgdinit(cs, cp, vp, p)) != 0)
goto bail;
memset(inbuf, 0x0, sizeof(inbuf));
ret = copyinstr(ci->ci_alg, inbuf, 256, NULL);
if (ret)
goto bail;
cs->sc_cfuncs = cryptfuncs_find(inbuf);
if (!cs->sc_cfuncs) {
ret = EINVAL;
goto bail;
}
/* right now we only support encblkno, so hard-code it */
memset(inbuf, 0x0, sizeof(inbuf));
ret = copyinstr(ci->ci_ivmethod, inbuf, sizeof(inbuf), NULL);
if (ret)
goto bail;
if (strcmp("encblkno", inbuf)) {
ret = EINVAL;
goto bail;
}
if (ci->ci_keylen > MAX_KEYSIZE) {
ret = EINVAL;
goto bail;
}
memset(inbuf, 0x0, sizeof(inbuf));
ret = copyin(ci->ci_key, inbuf, ci->ci_keylen);
if (ret)
goto bail;
cs->sc_cdata.cf_blocksize = ci->ci_blocksize;
cs->sc_cdata.cf_mode = CGD_CIPHER_CBC_ENCBLKNO;
cs->sc_cdata.cf_priv = cs->sc_cfuncs->cf_init(ci->ci_keylen, inbuf,
&cs->sc_cdata.cf_blocksize);
memset(inbuf, 0x0, sizeof(inbuf));
if (!cs->sc_cdata.cf_priv) {
printf("cgd: unable to initialize cipher\n");
ret = EINVAL; /* XXX is this the right error? */
goto bail;
}
cs->sc_dksc.sc_flags |= DKF_INITED;
/* Attach the disk. */
disk_attach(&cs->sc_dksc.sc_dkdev);
/* Try and read the disklabel. */
dk_getdisklabel(di, &cs->sc_dksc, 0 /* XXX ? */);
return 0;
bail:
(void)vn_close(vp, FREAD|FWRITE, p->p_ucred, p);
return ret;
}
/* ARGSUSED */
static int
cgd_ioctl_clr(struct cgd_softc *cs, void *data, struct proc *p)
{
(void)vn_close(cs->sc_tvn, FREAD|FWRITE, p->p_ucred, p);
cs->sc_cfuncs->cf_destroy(cs->sc_cdata.cf_priv);
free(cs->sc_tpath, M_DEVBUF);
cs->sc_dksc.sc_flags &= ~DKF_INITED;
disk_detach(&cs->sc_dksc.sc_dkdev);
return 0;
}
static int
cgdinit(struct cgd_softc *cs, char *cpath, struct vnode *vp,
struct proc *p)
{
struct dk_geom *pdg;
struct partinfo dpart;
struct vattr va;
size_t size;
int maxsecsize = 0;
int ret;
char tmppath[MAXPATHLEN];
cs->sc_dksc.sc_size = 0;
cs->sc_tvn = vp;
memset(tmppath, 0x0, sizeof(tmppath));
ret = copyinstr(cpath, tmppath, MAXPATHLEN, &cs->sc_tpathlen);
if (ret)
goto bail;
cs->sc_tpath = malloc(cs->sc_tpathlen, M_DEVBUF, M_WAITOK);
memcpy(cs->sc_tpath, tmppath, cs->sc_tpathlen);
if ((ret = VOP_GETATTR(vp, &va, p->p_ucred, p)) != 0)
goto bail;
cs->sc_tdev = va.va_rdev;
ret = VOP_IOCTL(vp, DIOCGPART, &dpart, FREAD, p->p_ucred, p);
if (ret)
goto bail;
maxsecsize =
((dpart.disklab->d_secsize > maxsecsize) ?
dpart.disklab->d_secsize : maxsecsize);
size = dpart.part->p_size;
if (!size) {
ret = ENODEV;
goto bail;
}
cs->sc_dksc.sc_size = size;
/*
* XXX here we should probe the underlying device. If we
* are accessing a partition of type RAW_PART, then
* we should populate our initial geometry with the
* geometry that we discover from the device.
*/
pdg = &cs->sc_dksc.sc_geom;
pdg->pdg_secsize = DEV_BSIZE;
pdg->pdg_ntracks = 1;
pdg->pdg_nsectors = 1024 * (1024 / pdg->pdg_secsize);
pdg->pdg_ncylinders = cs->sc_dksc.sc_size / pdg->pdg_nsectors;
bail:
if (ret && cs->sc_tpath)
free(cs->sc_tpath, M_DEVBUF);
return ret;
}
/*
* Our generic cipher entry point. This takes care of the
* IV mode and passes off the work to the specific cipher.
* We implement here the IV method ``encrypted block
* number''.
*
* For the encryption case, we accomplish this by setting
* up a struct uio where the first iovec of the source is
* the blocknumber and the first iovec of the dest is a
* sink. We then call the cipher with an IV of zero, and
* the right thing happens.
*
* For the decryption case, we use the same basic mechanism
* for symmetry, but we encrypt the block number in the
* first iovec.
*
* We mainly do this to avoid requiring the definition of
* an ECB mode.
*
* XXXrcd: for now we rely on our own crypto framework defined
* in dev/cgd_crypto.c. This will change when we
* get a generic kernel crypto framework.
*/
static void
blkno2blkno_buf(char *buf, daddr_t blkno)
{
int i;
/* Set up the blkno in blkno_buf, here we do not care much
* about the final layout of the information as long as we
* can guarantee that each sector will have a different IV
* and that the endianness of the machine will not affect
* the representation that we have chosen.
*
* We choose this representation, because it does not rely
* on the size of buf (which is the blocksize of the cipher),
* but allows daddr_t to grow without breaking existing
* disks.
*
* Note that blkno2blkno_buf does not take a size as input,
* and hence must be called on a pre-zeroed buffer of length
* greater than or equal to sizeof(daddr_t).
*/
for (i=0; i < sizeof(daddr_t); i++) {
*buf++ = blkno & 0xff;
blkno >>= 8;
}
}
static void
cgd_cipher(struct cgd_softc *cs, caddr_t dst, caddr_t src,
size_t len, daddr_t blkno, size_t secsize, int dir)
{
cfunc_cipher *cipher = cs->sc_cfuncs->cf_cipher;
struct uio dstuio;
struct uio srcuio;
struct iovec dstiov[2];
struct iovec srciov[2];
int blocksize = cs->sc_cdata.cf_blocksize;
char sink[blocksize];
char zero_iv[blocksize];
char blkno_buf[blocksize];
DPRINTF_FOLLOW(("cgd_cipher() dir=%d\n", dir));
DIAGCONDPANIC(len % blocksize != 0,
("cgd_cipher: len %% blocksize != 0"));
/* ensure that sizeof(daddr_t) <= blocksize (for encblkno IVing) */
DIAGCONDPANIC(sizeof(daddr_t) > blocksize,
("cgd_cipher: sizeof(daddr_t) > blocksize"));
memset(zero_iv, 0x0, sizeof(zero_iv));
dstuio.uio_iov = dstiov;
dstuio.uio_iovcnt = 2;
srcuio.uio_iov = srciov;
srcuio.uio_iovcnt = 2;
dstiov[0].iov_base = sink;
dstiov[0].iov_len = blocksize;
srciov[0].iov_base = blkno_buf;
srciov[0].iov_len = blocksize;
dstiov[1].iov_len = secsize;
srciov[1].iov_len = secsize;
for (; len > 0; len -= secsize) {
dstiov[1].iov_base = dst;
srciov[1].iov_base = src;
memset(blkno_buf, 0x0, sizeof(blkno_buf));
blkno2blkno_buf(blkno_buf, blkno);
if (dir == CGD_CIPHER_DECRYPT) {
dstuio.uio_iovcnt = 1;
srcuio.uio_iovcnt = 1;
IFDEBUG(CGDB_CRYPTO, hexprint("step 0: blkno_buf",
blkno_buf, sizeof(blkno_buf)));
cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio,
zero_iv, CGD_CIPHER_ENCRYPT);
memcpy(blkno_buf, sink, blocksize);
dstuio.uio_iovcnt = 2;
srcuio.uio_iovcnt = 2;
}
IFDEBUG(CGDB_CRYPTO, hexprint("step 1: blkno_buf",
blkno_buf, sizeof(blkno_buf)));
cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio, zero_iv, dir);
IFDEBUG(CGDB_CRYPTO, hexprint("step 2: sink",
sink, sizeof(sink)));
dst += secsize;
src += secsize;
blkno++;
}
}
#ifdef DEBUG
static void
hexprint(char *start, void *buf, int len)
{
char *c = buf;
DIAGCONDPANIC(len < 0, ("hexprint: called with len < 0"));
printf("%s: len=%06d 0x", start, len);
while (len--)
printf("%02x", (unsigned) *c++);
}
#endif
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