diff options
-rw-r--r-- | sys/geom/geom_bsd.c | 372 | ||||
-rw-r--r-- | sys/geom/geom_bsd_enc.c | 45 | ||||
-rw-r--r-- | sys/sys/disklabel.h | 2 |
3 files changed, 150 insertions, 269 deletions
diff --git a/sys/geom/geom_bsd.c b/sys/geom/geom_bsd.c index f66ada3..7fa11a2 100644 --- a/sys/geom/geom_bsd.c +++ b/sys/geom/geom_bsd.c @@ -58,6 +58,8 @@ #define ALPHA_LABEL_OFFSET 64 +#define LABELSIZE (148 + 16 * MAXPARTITIONS) + static void g_bsd_hotwrite(void *arg, int flag); /* * Our private data about one instance. All the rest is handled by the @@ -69,123 +71,16 @@ struct g_bsd_softc { off_t mbroffset; off_t rawoffset; struct disklabel ondisk; - struct disklabel inram; + u_char label[LABELSIZE]; u_char labelsum[16]; }; -static int -g_bsd_ondisk_size(void) -{ - return (148 + 16 * MAXPARTITIONS); -} - -/* - * For reasons which were valid and just in their days, FreeBSD/i386 uses - * absolute disk-addresses in disklabels. The way it works is that the - * p_offset field of all partitions have the first sector number of the - * disk slice added to them. This was hidden kernel-magic, userland did - * not see these offsets. These two functions subtract and add them - * while converting from the "ondisk" to the "inram" labels and vice - * versa. - */ -static void -ondisk2inram(struct g_bsd_softc *sc) -{ - struct partition *ppp; - struct disklabel *dl; - int i; - - sc->inram = sc->ondisk; - dl = &sc->inram; - - /* Basic sanity-check needed to avoid mistakes. */ - if (dl->d_magic != DISKMAGIC || dl->d_magic2 != DISKMAGIC) - return; - if (dl->d_npartitions > MAXPARTITIONS) - return; - - sc->rawoffset = dl->d_partitions[RAW_PART].p_offset; - for (i = 0; i < dl->d_npartitions; i++) { - ppp = &dl->d_partitions[i]; - if (ppp->p_size != 0 && ppp->p_offset < sc->rawoffset) - sc->rawoffset = 0; - } - if (sc->rawoffset > 0) { - for (i = 0; i < dl->d_npartitions; i++) { - ppp = &dl->d_partitions[i]; - if (ppp->p_offset != 0) - ppp->p_offset -= sc->rawoffset; - } - } - dl->d_checksum = 0; - dl->d_checksum = dkcksum(&sc->inram); -} - -static void -inram2ondisk(struct g_bsd_softc *sc) -{ - struct partition *ppp; - int i; - - sc->ondisk = sc->inram; - if (sc->mbroffset != 0) - sc->rawoffset = sc->mbroffset / sc->inram.d_secsize; - if (sc->rawoffset != 0) { - for (i = 0; i < sc->inram.d_npartitions; i++) { - ppp = &sc->ondisk.d_partitions[i]; - if (ppp->p_size > 0) - ppp->p_offset += sc->rawoffset; - else - ppp->p_offset = 0; - } - } - sc->ondisk.d_checksum = 0; - sc->ondisk.d_checksum = dkcksum(&sc->ondisk); -} - -/* - * Check that this looks like a valid disklabel, but be prepared - * to get any kind of junk. The checksum must be checked only - * after this function returns success to prevent a bogus d_npartitions - * value from tripping us up. - */ -static int -g_bsd_checklabel(struct disklabel *dl) -{ - struct partition *ppp; - int i; - - if (dl->d_magic != DISKMAGIC || dl->d_magic2 != DISKMAGIC) - return (EINVAL); - /* - * If the label specifies more partitions than we can handle - * we have to reject it: If people updated the label they would - * trash it, and that would break the checksum. - */ - if (dl->d_npartitions > MAXPARTITIONS) - return (EINVAL); - - for (i = 0; i < dl->d_npartitions; i++) { - ppp = &dl->d_partitions[i]; - /* Cannot extend past unit. */ - if (ppp->p_size != 0 && - ppp->p_offset + ppp->p_size > dl->d_secperunit) { - return (EINVAL); - } - } - return (0); -} - /* * Modify our slicer to match proposed disklabel, if possible. - * First carry out all the simple checks, then lock topology - * and check that no open providers are affected negatively - * then carry out all the changes. - * - * NB: Returns with topology held only if successful return. + * This is where we make sure we don't do something stupid. */ static int -g_bsd_modify(struct g_geom *gp, struct disklabel *dl) +g_bsd_modify(struct g_geom *gp, u_char *label) { int i, error; struct partition *ppp; @@ -193,33 +88,25 @@ g_bsd_modify(struct g_geom *gp, struct disklabel *dl) struct g_consumer *cp; struct g_bsd_softc *ms; u_int secsize, u; - off_t mediasize; + off_t mediasize, rawoffset, o; + struct disklabel dl; + MD5_CTX md5sum; - /* Basic check that this is indeed a disklabel. */ - error = g_bsd_checklabel(dl); - if (error) - return (error); + g_topology_assert(); + gsp = gp->softc; + ms = gsp->softc; - /* Make sure the checksum is OK. */ - if (dkcksum(dl) != 0) - return (EINVAL); + error = bsd_disklabel_le_dec(label, &dl, MAXPARTITIONS); + if (error) { +printf("HERE %s %d\n", __FILE__, __LINE__); + return (error); + } /* Get dimensions of our device. */ cp = LIST_FIRST(&gp->consumer); secsize = cp->provider->sectorsize; mediasize = cp->provider->mediasize; -#ifdef nolonger - /* - * The raw-partition must start at zero. We do not check that the - * size == mediasize because this is overly restrictive. We have - * already tested in g_bsd_checklabel() that it is not longer. - * XXX: RAW_PART is archaic anyway, and we should drop it. - */ - if (dl->d_partitions[RAW_PART].p_offset != 0) - return (EINVAL); -#endif - #ifdef notyet /* * Indications are that the d_secperunit is not correctly @@ -229,71 +116,80 @@ g_bsd_modify(struct g_geom *gp, struct disklabel *dl) * may be in order. */ /* The label cannot claim a larger size than the media. */ - if ((off_t)dl->d_secperunit * dl->d_secsize > mediasize) + if ((off_t)dl.d_secperunit * dl.d_secsize > mediasize) return (EINVAL); #endif - /* ... or a smaller sector size. */ - if (dl->d_secsize < secsize) + if (dl.d_secsize < secsize) { +printf("HERE %s %d\n", __FILE__, __LINE__); return (EINVAL); + } /* ... or a non-multiple sector size. */ - if (dl->d_secsize % secsize != 0) + if (dl.d_secsize % secsize != 0) { +printf("HERE %s %d\n", __FILE__, __LINE__); return (EINVAL); + } - g_topology_lock(); + /* Historical braindamage... */ + rawoffset = (off_t)dl.d_partitions[RAW_PART].p_offset * dl.d_secsize; + for (i = 0; i < dl.d_npartitions; i++) { + ppp = &dl.d_partitions[i]; + if (ppp->p_size == 0) + continue; + o = (off_t)ppp->p_offset * dl.d_secsize; + + if (o < rawoffset) + rawoffset = 0; + } /* Don't munge open partitions. */ - gsp = gp->softc; - ms = gsp->softc; - for (i = 0; i < dl->d_npartitions; i++) { - ppp = &dl->d_partitions[i]; + for (i = 0; i < dl.d_npartitions; i++) { + 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, - (off_t)ppp->p_offset * dl->d_secsize, - (off_t)ppp->p_size * dl->d_secsize, - dl->d_secsize, + o - rawoffset, + (off_t)ppp->p_size * dl.d_secsize, + dl.d_secsize, "%s%c", gp->name, 'a' + i); - if (error) { - g_topology_unlock(); + if (error) return (error); - } } /* Look good, go for it... */ for (u = 0; u < gsp->nslice; u++) { - ppp = &dl->d_partitions[u]; + 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, - (off_t)ppp->p_offset * dl->d_secsize, - (off_t)ppp->p_size * dl->d_secsize, - dl->d_secsize, + o - rawoffset, + (off_t)ppp->p_size * dl.d_secsize, + dl.d_secsize, "%s%c", gp->name, 'a' + u); } - g_slice_conf_hot(gp, 0, ms->labeloffset, g_bsd_ondisk_size(), - G_SLICE_HOT_ALLOW, G_SLICE_HOT_DENY, G_SLICE_HOT_CALL); - gsp->hot = g_bsd_hotwrite; - return (0); -} -/* - * Calculate a disklabel checksum for a little-endian byte-stream. - * We need access to the decoded disklabel because the checksum only - * covers the partition data for the first d_npartitions. - */ -static int -g_bsd_lesum(struct disklabel *dl, u_char *p) -{ - u_char *pe; - uint16_t sum; - - pe = p + 148 + 16 * dl->d_npartitions; - sum = 0; - while (p < pe) { - sum ^= le16dec(p); - p += 2; - } - return (sum); + /* Update our softc */ + ms->ondisk = dl; + if (label != ms->label) + bcopy(label, ms->label, LABELSIZE); + 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); } /* @@ -323,17 +219,9 @@ g_bsd_try(struct g_geom *gp, struct g_slicer *gsp, struct g_consumer *cp, int se /* Decode into our native format. */ dl = &ms->ondisk; - bsd_disklabel_le_dec(buf + secoff, dl); - - ondisk2inram(ms); - - dl = &ms->inram; - /* Does it look like a label at all? */ - if (g_bsd_checklabel(dl)) - error = ENOENT; - /* ... and does the raw data have a good checksum? */ - if (error == 0 && g_bsd_lesum(dl, buf + secoff) != 0) - error = ENOENT; + error = bsd_disklabel_le_dec(buf + secoff, dl, MAXPARTITIONS); + if (!error) + bcopy(buf + secoff, ms->label, LABELSIZE); /* Remember to free the buffer g_read_data() gave us. */ g_free(buf); @@ -357,47 +245,41 @@ g_bsd_ioctl(void *arg, int flag) struct g_geom *gp; struct g_slicer *gsp; struct g_bsd_softc *ms; - struct disklabel *dl; struct g_ioctl *gio; struct g_consumer *cp; - u_char *buf; + u_char *buf, *label; off_t secoff; u_int secsize; int error, i; uint64_t sum; + g_topology_assert(); bp = arg; if (flag == EV_CANCEL) { g_io_deliver(bp, ENXIO); return; } - /* We don't need topology for now. */ - g_topology_unlock(); gp = bp->bio_to->geom; gsp = gp->softc; ms = gsp->softc; gio = (struct g_ioctl *)bp->bio_data; + label = g_malloc(LABELSIZE, M_WAITOK); + /* The disklabel to set is the ioctl argument. */ - dl = gio->data; + bsd_disklabel_le_enc(label, gio->data); /* Validate and modify our slice instance to match. */ - error = g_bsd_modify(gp, dl); /* Picks up topology lock on success. */ - if (error) { - g_topology_lock(); + error = g_bsd_modify(gp, label); /* Picks up topology lock on success. */ + g_free(label); + if (error || gio->cmd == DIOCSDINFO) { g_io_deliver(bp, error); return; } - /* Update our copy of the disklabel. */ - ms->inram = *dl; - inram2ondisk(ms); - - if (gio->cmd == DIOCSDINFO) { - g_io_deliver(bp, 0); - return; - } + KASSERT(gio->cmd == DIOCWDINFO, ("Unknown ioctl in g_bsd_ioctl")); + cp = LIST_FIRST(&gp->consumer); /* Get sector size, we need it to read data. */ secsize = cp->provider->sectorsize; @@ -407,8 +289,7 @@ g_bsd_ioctl(void *arg, int flag) g_io_deliver(bp, error); return; } - dl = &ms->ondisk; - bsd_disklabel_le_enc(buf + secoff, dl); + bcopy(ms->label, buf + secoff, sizeof(ms->label)); if (ms->labeloffset == ALPHA_LABEL_OFFSET) { sum = 0; for (i = 0; i < 63; i++) @@ -430,7 +311,6 @@ g_bsd_diocbsdbb(dev_t dev, u_long cmd __unused, caddr_t data, int fflag __unused struct g_geom *gp; struct g_slicer *gsp; struct g_bsd_softc *ms; - struct disklabel *dl; struct g_consumer *cp; u_char *buf; void *p; @@ -447,33 +327,26 @@ g_bsd_diocbsdbb(dev_t dev, u_long cmd __unused, caddr_t data, int fflag __unused buf = g_malloc(BBSIZE, M_WAITOK); p = *(void **)data; error = copyin(p, buf, BBSIZE); - if (error) { - g_free(buf); - return (error); - } - /* The disklabel to set is the ioctl argument. */ - dl = (void *)(buf + ms->labeloffset); - - DROP_GIANT(); - - /* Validate and modify our slice instance to match. */ - error = g_bsd_modify(gp, dl); /* Picks up topology lock on success. */ if (!error) { - cp = LIST_FIRST(&gp->consumer); - secsize = cp->provider->sectorsize; - dl = &ms->ondisk; - bsd_disklabel_le_enc(buf + ms->labeloffset, dl); - if (ms->labeloffset == ALPHA_LABEL_OFFSET) { - sum = 0; - for (i = 0; i < 63; i++) - sum += le64dec(buf + i * 8); - le64enc(buf + 504, sum); + DROP_GIANT(); + g_topology_lock(); + /* Validate and modify our slice instance to match. */ + error = g_bsd_modify(gp, buf + ms->labeloffset); + if (!error) { + cp = LIST_FIRST(&gp->consumer); + secsize = cp->provider->sectorsize; + if (ms->labeloffset == ALPHA_LABEL_OFFSET) { + sum = 0; + for (i = 0; i < 63; i++) + sum += le64dec(buf + i * 8); + le64enc(buf + 504, sum); + } + error = g_write_data(cp, 0, buf, BBSIZE); } - error = g_write_data(cp, 0, buf, BBSIZE); g_topology_unlock(); + PICKUP_GIANT(); } g_free(buf); - PICKUP_GIANT(); return (error); } @@ -490,10 +363,10 @@ g_bsd_hotwrite(void *arg, int flag) struct g_slicer *gsp; struct g_slice *gsl; struct g_bsd_softc *ms; - struct g_bsd_softc fake; u_char *p; int error; + g_topology_assert(); /* * We should never get canceled, because that would amount to a removal * of the geom while there was outstanding I/O requests. @@ -506,28 +379,11 @@ g_bsd_hotwrite(void *arg, int flag) gsl = &gsp->slices[bp->bio_to->index]; p = (u_char*)bp->bio_data + ms->labeloffset - (bp->bio_offset + gsl->offset); - bsd_disklabel_le_dec(p, &fake.ondisk); - - ondisk2inram(&fake); - if (g_bsd_checklabel(&fake.inram)) { - g_io_deliver(bp, EPERM); - return; - } - if (g_bsd_lesum(&fake.ondisk, p) != 0) { - g_io_deliver(bp, EPERM); - return; - } - g_topology_unlock(); - error = g_bsd_modify(gp, &fake.inram); /* May pick up topology. */ + error = g_bsd_modify(gp, p); if (error) { g_io_deliver(bp, EPERM); - g_topology_lock(); return; } - /* Update our copy of the disklabel. */ - ms->inram = fake.inram; - inram2ondisk(ms); - bsd_disklabel_le_enc(p, &ms->ondisk); g_slice_finish_hot(bp); } @@ -577,7 +433,7 @@ g_bsd_start(struct bio *bp) switch (gio->cmd) { case DIOCGDINFO: /* Return a copy of the disklabel to userland. */ - bcopy(&ms->inram, gio->data, sizeof(ms->inram)); + bsd_disklabel_le_dec(ms->label, gio->data, MAXPARTITIONS); g_io_deliver(bp, 0); return (1); case DIOCBSDBB: @@ -629,10 +485,10 @@ g_bsd_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_ } else if (pp != NULL) { if (indent == NULL) sbuf_printf(sb, " ty %d", - ms->inram.d_partitions[pp->index].p_fstype); + ms->ondisk.d_partitions[pp->index].p_fstype); else sbuf_printf(sb, "%s<type>%d</type>\n", indent, - ms->inram.d_partitions[pp->index].p_fstype); + ms->ondisk.d_partitions[pp->index].p_fstype); } } @@ -663,11 +519,10 @@ g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags) struct g_consumer *cp; int error, i; struct g_bsd_softc *ms; - struct disklabel *dl; u_int secsize; struct g_slicer *gsp; - MD5_CTX md5sum; u_char hash[16]; + MD5_CTX md5sum; g_trace(G_T_TOPOLOGY, "bsd_taste(%s,%s)", mp->name, pp->name); g_topology_assert(); @@ -691,13 +546,6 @@ g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags) return (NULL); /* - * Now that we have attached to and opened our provider, we do - * not need the topology lock until we change the topology again - * next time. - */ - g_topology_unlock(); - - /* * Fill in the optional details, in our case we have a dumpconf * routine which the "slice" code should call at the right time */ @@ -759,10 +607,8 @@ g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags) * partition) we calculate an MD5 and ask if other BSD's * below us love that label. If they do, we don't. */ - - dl = &ms->inram; MD5Init(&md5sum); - MD5Update(&md5sum, (u_char *)dl, sizeof(dl)); + MD5Update(&md5sum, ms->label, sizeof(ms->label)); MD5Final(ms->labelsum, &md5sum); error = g_getattr("BSD::labelsum", cp, &hash); @@ -773,19 +619,19 @@ g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags) * Process the found disklabel, and modify our "slice" * instance to match it, if possible. */ - error = g_bsd_modify(gp, dl); /* Picks up topology lock. */ - if (!error) - g_topology_unlock(); - break; + error = g_bsd_modify(gp, ms->label); } while (0); /* Success or failure, we can close our provider now. */ - g_topology_lock(); error = g_access_rel(cp, -1, 0, 0); /* If we have configured any providers, return the new geom. */ - if (gsp->nprovider > 0) + 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); + gsp->hot = g_bsd_hotwrite; return (gp); + } /* * ...else push the "self-destruct" button, by spoiling our own * consumer. This triggers a call to g_slice_spoiled which will diff --git a/sys/geom/geom_bsd_enc.c b/sys/geom/geom_bsd_enc.c index 8292497..a3a7fd9 100644 --- a/sys/geom/geom_bsd_enc.c +++ b/sys/geom/geom_bsd_enc.c @@ -44,10 +44,12 @@ #include <sys/types.h> #include <sys/endian.h> #include <sys/disklabel.h> +#include <sys/errno.h> #ifdef _KERNEL #include <sys/systm.h> #else #include <string.h> +#include <stdio.h> #endif void @@ -61,12 +63,38 @@ bsd_partition_le_dec(u_char *ptr, struct partition *d) d->p_cpg = le16dec(ptr + 14); } -void -bsd_disklabel_le_dec(u_char *ptr, struct disklabel *d) +int +bsd_disklabel_le_dec(u_char *ptr, struct disklabel *d, int maxpart) { int i; + u_char *p, *pe; + uint16_t sum; d->d_magic = le32dec(ptr + 0); + if (d->d_magic != DISKMAGIC) + return(EINVAL); + + d->d_magic2 = le32dec(ptr + 132); + if (d->d_magic2 != DISKMAGIC) { +printf("HERE %s %d\n", __FILE__, __LINE__); + return(EINVAL); + } + + d->d_npartitions = le16dec(ptr + 138); + if (d->d_npartitions > maxpart) { +printf("HERE %s %d\n", __FILE__, __LINE__); + return(EINVAL); + } + + pe = ptr + 148 + 16 * d->d_npartitions; + sum = 0; + for (p = ptr; p < pe; p += 2) + sum ^= le16dec(p); + if (sum != 0) { +printf("HERE %s %d\n", __FILE__, __LINE__); + return(EINVAL); + } + d->d_type = le16dec(ptr + 4); d->d_subtype = le16dec(ptr + 6); bcopy(ptr + 8, d->d_typename, 16); @@ -97,13 +125,13 @@ bsd_disklabel_le_dec(u_char *ptr, struct disklabel *d) d->d_spare[2] = le32dec(ptr + 120); d->d_spare[3] = le32dec(ptr + 124); d->d_spare[4] = le32dec(ptr + 128); - d->d_magic2 = le32dec(ptr + 132); d->d_checksum = le16dec(ptr + 136); d->d_npartitions = le16dec(ptr + 138); d->d_bbsize = le32dec(ptr + 140); d->d_sbsize = le32dec(ptr + 144); for (i = 0; i < MAXPARTITIONS; i++) bsd_partition_le_dec(ptr + 148 + 16 * i, &d->d_partitions[i]); + return(0); } void @@ -121,6 +149,8 @@ void bsd_disklabel_le_enc(u_char *ptr, struct disklabel *d) { int i; + u_char *p, *pe; + uint16_t sum; le32enc(ptr + 0, d->d_magic); le16enc(ptr + 4, d->d_type); @@ -154,10 +184,15 @@ bsd_disklabel_le_enc(u_char *ptr, struct disklabel *d) le32enc(ptr + 124, d->d_spare[3]); le32enc(ptr + 128, d->d_spare[4]); le32enc(ptr + 132, d->d_magic2); - le16enc(ptr + 136, d->d_checksum); + le16enc(ptr + 136, 0); le16enc(ptr + 138, d->d_npartitions); le32enc(ptr + 140, d->d_bbsize); le32enc(ptr + 144, d->d_sbsize); - for (i = 0; i < MAXPARTITIONS; i++) + for (i = 0; i < d->d_npartitions; i++) bsd_partition_le_enc(ptr + 148 + 16 * i, &d->d_partitions[i]); + pe = ptr + 148 + 16 * d->d_npartitions; + sum = 0; + for (p = ptr; p < pe; p += 2) + sum ^= le16dec(p); + le16enc(ptr + 136, sum); } diff --git a/sys/sys/disklabel.h b/sys/sys/disklabel.h index baf8874..ddcf21a 100644 --- a/sys/sys/disklabel.h +++ b/sys/sys/disklabel.h @@ -305,7 +305,7 @@ static const char *fstypenames[] = { * bytestring. */ void bsd_partition_le_dec(u_char *ptr, struct partition *d); -void bsd_disklabel_le_dec(u_char *ptr, struct disklabel *d); +int bsd_disklabel_le_dec(u_char *ptr, struct disklabel *d, int maxpart); void bsd_partition_le_enc(u_char *ptr, struct partition *d); void bsd_disklabel_le_enc(u_char *ptr, struct disklabel *d); |