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/*-* Copyright 2005, Anatoli Klassen <anatoli@aksoft.net>* All rights reserved.** The code is based on code of geom_bsd module by Poul-Henning Kamp.** 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.*//** This is the method for dealing with BSD disklabels. It has been* extensively (by my standards at least) commented, in the vain hope that* it will serve as the source in future copy&paste operations.*/#include <sys/param.h>#include <sys/systm.h>#include <sys/kernel.h>#include <sys/bio.h>#include <sys/malloc.h>#include <sys/lock.h>#include <sys/md5.h>#include <sys/errno.h>#include <geom/geom.h>#include <geom/geom_slice.h>#include "disklabel.h"#define NBSD_CLASS_NAME "NetBSD"#define LABELSIZE (148 + 16 * NBSD_MAXPARTITIONS)/** Our private data about one instance. All the rest is handled by the* slice code and stored in its softc, so this is just the stuff* specific to BSD disklabels.*/struct g_nbsd_softc {int mbrtype;off_t labeloffset;off_t mbroffset;off_t rawoffset;struct disklabel ondisk;u_char label[LABELSIZE];u_char labelsum[16];};/** Modify our slicer to match proposed disklabel, if possible.* This is where we make sure we don't do something stupid.*/static intg_nbsd_modify(struct g_geom *gp, struct g_nbsd_softc *ms){char useable[NBSD_MAXPARTITIONS];MD5_CTX md5sum;struct partition *ppp;struct g_slicer *gsp;struct g_consumer *cp;struct disklabel *dl;off_t rawoffset, fullsize, o;int i, error;u_int secsize, u;g_topology_assert();gsp = gp->softc;dl = &ms->ondisk;/* Get dimensions of our device. */cp = LIST_FIRST(&gp->consumer);secsize = cp->provider->sectorsize;/* ... or a smaller sector size. */if (dl->d_secsize < secsize) {return (EINVAL);}/* ... or a non-multiple sector size. */if (dl->d_secsize % secsize != 0) {return (EINVAL);}rawoffset = ms->mbroffset;fullsize = cp->provider->mediasize;for (i = 0; i < dl->d_npartitions; i++) {ppp = &dl->d_partitions[i];/* skip partitions with no type or outside of slide */if (ppp->p_size == 0 || ppp->p_fstype == 0 ||(off_t)ppp->p_offset * dl->d_secsize < rawoffset ||(off_t)(ppp->p_offset + ppp->p_size) * dl->d_secsize> (rawoffset + fullsize))useable[i] = 0;elseuseable[i] = 1;}/* Don't munge open partitions. */for (i = 0; i < dl->d_npartitions; i++) {if(!useable[i]) continue;ppp = &dl->d_partitions[i];o = (off_t)ppp->p_offset * dl->d_secsize;if (o == 0)o = rawoffset;error = g_slice_config(gp, i, G_SLICE_CONFIG_CHECK,o - rawoffset, (off_t)ppp->p_size * dl->d_secsize, dl->d_secsize,"%s%c", gp->name, 'a' + i);if (error)return (error);}/* Look good, go for it... */for (u = 0; u < gsp->nslice; u++) {if(!useable[u]) continue;ppp = &dl->d_partitions[u];o = (off_t)ppp->p_offset * dl->d_secsize;if (o == 0)o = rawoffset;g_slice_config(gp, u, G_SLICE_CONFIG_SET,o - rawoffset,(off_t)ppp->p_size * dl->d_secsize,dl->d_secsize,"%s%c", gp->name, 'a' + u);}/* Update our softc */ms->rawoffset = rawoffset;/** In order to avoid recursively attaching to the same* on-disk label (it's usually visible through the 'c'* partition) we calculate an MD5 and ask if other BSD's* below us love that label. If they do, we don't.*/MD5Init(&md5sum);MD5Update(&md5sum, ms->label, sizeof(ms->label));MD5Final(ms->labelsum, &md5sum);return (0);}/** This is an internal helper function, called multiple times from the taste* function to try to locate a disklabel on the disk. More civilized formats* will not need this, as there is only one possible place on disk to look* for the magic spot.*/static intg_nbsd_try(struct g_geom *gp, struct g_slicer *gsp, struct g_consumer *cp,int secsize, struct g_nbsd_softc *ms, off_t offset){int error;u_char *buf;struct disklabel *dl;off_t secoff;/** We need to read entire aligned sectors, and we assume that the* disklabel does not span sectors, so one sector is enough.*/error = 0;secoff = offset % secsize;buf = g_read_data(cp, offset - secoff, secsize, &error);if (buf == NULL || error != 0)return (ENOENT);/* Decode into our native format. */dl = &ms->ondisk;error = nbsd_disklabel_le_dec(buf + secoff, dl, NBSD_MAXPARTITIONS);/* do not recognize slices which will be recognized by geom_bsd module */if (!error)if (ms->mbrtype == MBR_FREEBSD &&dl->d_npartitions <= FREEBSD_MAXPARTITIONS)error = EINVAL;if (!error)bcopy(buf + secoff, ms->label, LABELSIZE);/* Remember to free the buffer g_read_data() gave us. */g_free(buf);ms->labeloffset = offset;return (error);}/*-* This start routine is only called for non-trivial requests, all the* trivial ones are handled autonomously by the slice code.* For requests we handle here, we must call the g_io_deliver() on the* bio, and return non-zero to indicate to the slice code that we did so.* This code executes in the "DOWN" I/O path, this means:* * No sleeping.* * Don't grab the topology lock.* * Don't call biowait, g_getattr(), g_setattr() or g_read_data()*/static intg_nbsd_ioctl(struct g_provider *pp, u_long cmd, void *data, int fflag, struct thread *td){return (ENOIOCTL);}static intg_nbsd_start(struct bio *bp){struct g_geom *gp;struct g_nbsd_softc *ms;struct g_slicer *gsp;gp = bp->bio_to->geom;gsp = gp->softc;ms = gsp->softc;if (bp->bio_cmd == BIO_GETATTR) {if (g_handleattr(bp, "NBSD::labelsum", ms->labelsum,sizeof(ms->labelsum)))return (1);}return (0);}/** Dump configuration information in XML format.* Notice that the function is called once for the geom and once for each* consumer and provider. We let g_slice_dumpconf() do most of the work.*/static voidg_nbsd_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,struct g_consumer *cp, struct g_provider *pp){struct g_nbsd_softc *ms;struct g_slicer *gsp;gsp = gp->softc;ms = gsp->softc;g_slice_dumpconf(sb, indent, gp, cp, pp);if (indent != NULL && pp == NULL && cp == NULL) {sbuf_printf(sb, "%s<labeloffset>%jd</labeloffset>\n",indent, (intmax_t)ms->labeloffset);sbuf_printf(sb, "%s<rawoffset>%jd</rawoffset>\n",indent, (intmax_t)ms->rawoffset);sbuf_printf(sb, "%s<mbroffset>%jd</mbroffset>\n",indent, (intmax_t)ms->mbroffset);} else if (pp != NULL) {if (indent == NULL)sbuf_printf(sb, " ty %d",ms->ondisk.d_partitions[pp->index].p_fstype);elsesbuf_printf(sb, "%s<type>%d</type>\n", indent,ms->ondisk.d_partitions[pp->index].p_fstype);}}/** The taste function is called from the event-handler, with the topology* lock already held and a provider to examine. The flags are unused.** If flags == G_TF_NORMAL, the idea is to take a bite of the provider and* if we find valid, consistent magic on it, build a geom on it.* any magic bits which indicate that we should automatically put a BSD* geom on it.** There may be cases where the operator would like to put a BSD-geom on* providers which do not meet all of the requirements. This can be done* by instead passing the G_TF_INSIST flag, which will override these* checks.** The final flags value is G_TF_TRANSPARENT, which instructs the method* to put a geom on top of the provider and configure it to be as transparent* as possible. This is not really relevant to the BSD method and therefore* not implemented here.*/static struct g_geom *g_nbsd_taste(struct g_class *mp, struct g_provider *pp, int flags){MD5_CTX md5sum;u_char hash[16];struct g_geom *gp;struct g_consumer *cp;struct g_nbsd_softc *ms;struct g_slicer *gsp;int error;u_int secsize;g_trace(G_T_TOPOLOGY, "nbsd_taste(%s,%s)", mp->name, pp->name);g_topology_assert();/* We don't implement transparent inserts. */if (flags == G_TF_TRANSPARENT)return (NULL);/** BSD labels are a subclass of the general "slicing" topology so* a lot of the work can be done by the common "slice" code.* Create a geom with space for NBSD_MAXPARTITIONS providers, one consumer* and a softc structure for us. Specify the provider to attach* the consumer to and our "start" routine for special requests.* The provider is opened with mode (1,0,0) so we can do reads* from it.*/gp = g_slice_new(mp, NBSD_MAXPARTITIONS, pp, &cp, &ms,sizeof(*ms), g_nbsd_start);if (gp == NULL)return (NULL);/* Get the geom_slicer softc from the geom. */gsp = gp->softc;/** The do...while loop here allows us to have multiple escapes* using a simple "break". This improves code clarity without* ending up in deep nesting and without using goto or come from.*/do {/** If the provider is an MBR we will only auto attach* to type 165|166|169 slices in the G_TF_NORMAL case. We will* attach to any other type.*/error = g_getattr("MBR::type", cp, &ms->mbrtype);if (!error) {if (ms->mbrtype != MBR_OPENBSD && ms->mbrtype != MBR_NETBSD &&ms->mbrtype != MBR_FREEBSD && flags == G_TF_NORMAL)break;error = g_getattr("MBR::offset", cp, &ms->mbroffset);if (error)break;}/* Same thing if we are inside a PC98 *//* XXX not implemented *//* Get sector size, we need it to read data. */secsize = cp->provider->sectorsize;if (secsize < 512)break;/* First look for a label at the start of the second sector. */error = g_nbsd_try(gp, gsp, cp, secsize, ms, secsize);/* If we didn't find a label, punt. */if (error)break;/** In order to avoid recursively attaching to the same* on-disk label (it's usually visible through the 'c'* partition) we calculate an MD5 and ask if other BSD's* below us love that label. If they do, we don't.*/MD5Init(&md5sum);MD5Update(&md5sum, ms->label, sizeof(ms->label));MD5Final(ms->labelsum, &md5sum);error = g_getattr("NBSD::labelsum", cp, &hash);if (!error && !bcmp(ms->labelsum, hash, sizeof(hash)))break;/** Process the found disklabel, and modify our "slice"* instance to match it, if possible.*/error = g_nbsd_modify(gp, ms);} while (0);/* Success or failure, we can close our provider now. */g_access(cp, -1, 0, 0);/* If we have configured any providers, return the new geom. */if (gsp->nprovider > 0) {g_slice_conf_hot(gp, 0, ms->labeloffset, LABELSIZE,G_SLICE_HOT_ALLOW, G_SLICE_HOT_DENY, G_SLICE_HOT_CALL);return (gp);}/** ...else push the "self-destruct" button, by spoiling our own* consumer. This triggers a call to g_slice_spoiled which will* dismantle what was setup.*/g_slice_spoiled(cp);return (NULL);}/** NB! curthread is user process which GCTL'ed.*/static voidg_nbsd_config(struct gctl_req *req, struct g_class *mp, char const *verb){struct g_geom *gp;struct g_slicer *gsp;struct g_consumer *cp;struct g_nbsd_softc *ms;g_topology_assert();gp = gctl_get_geom(req, mp, "geom");if (gp == NULL)return;cp = LIST_FIRST(&gp->consumer);gsp = gp->softc;ms = gsp->softc;if (!strcmp(verb, "read mbroffset")) {gctl_set_param(req, "mbroffset",&ms->mbroffset, sizeof(ms->mbroffset));return;} else {gctl_error(req, "Unknown verb parameter");}return;}/* Finally, register with GEOM infrastructure. */static struct g_class g_nbsd_class = {.name = NBSD_CLASS_NAME,.version = G_VERSION,.taste = g_nbsd_taste,.ctlreq = g_nbsd_config,.dumpconf = g_nbsd_dumpconf,.ioctl = g_nbsd_ioctl,};DECLARE_GEOM_CLASS(g_nbsd_class, g_nbsd);