geom_mbr.c revision 97078 
1/*-
2 * Copyright (c) 2002 Poul-Henning Kamp
3 * Copyright (c) 2002 Networks Associates Technology, Inc.
4 * All rights reserved.
5 *
6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7 * and NAI Labs, the Security Research Division of Network Associates, Inc.
8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9 * DARPA CHATS research program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. The names of the authors may not be used to endorse or promote
20 *    products derived from this software without specific prior written
21 *    permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * $FreeBSD: head/sys/geom/geom_mbr.c 97078 2002-05-21 20:33:49Z phk $
36 */
37
38#include <sys/param.h>
39#ifndef _KERNEL
40#include <stdio.h>
41#include <string.h>
42#include <signal.h>
43#include <sys/param.h>
44#include <stdlib.h>
45#include <err.h>
46#else
47#include <sys/systm.h>
48#include <sys/kernel.h>
49#include <sys/malloc.h>
50#include <sys/bio.h>
51#include <sys/lock.h>
52#include <sys/mutex.h>
53#endif
54
55#include <sys/errno.h>
56#include <sys/disklabel.h>
57#include <sys/sbuf.h>
58#include <geom/geom.h>
59#include <geom/geom_slice.h>
60
61#define MBR_CLASS_NAME "MBR"
62#define MBREXT_CLASS_NAME "MBREXT"
63
64static void
65g_dec_dos_partition(u_char *ptr, struct dos_partition *d)
66{
67
68	d->dp_flag = ptr[0];
69	d->dp_shd = ptr[1];
70	d->dp_ssect = ptr[2];
71	d->dp_scyl = ptr[3];
72	d->dp_typ = ptr[4];
73	d->dp_ehd = ptr[5];
74	d->dp_esect = ptr[6];
75	d->dp_ecyl = ptr[7];
76	d->dp_start = g_dec_le4(ptr + 8);
77	d->dp_size = g_dec_le4(ptr + 12);
78}
79
80#if 0
81static void
82g_enc_dos_partition(u_char *ptr, struct dos_partition *d)
83{
84
85	ptr[0] = d->dp_flag;
86	ptr[1] = d->dp_shd;
87	ptr[2] = d->dp_ssect;
88	ptr[3] = d->dp_scyl;
89	ptr[4] = d->dp_typ;
90	ptr[5] = d->dp_ehd;
91	ptr[6] = d->dp_esect;
92	ptr[7] = d->dp_ecyl;
93	g_enc_le4(ptr + 8, d->dp_start);
94	g_enc_le4(ptr + 12, d->dp_size);
95}
96#endif
97
98struct g_mbr_softc {
99	int		type [NDOSPART];
100	struct dos_partition dospart[NDOSPART];
101};
102
103static int
104g_mbr_start(struct bio *bp)
105{
106	struct g_provider *pp;
107	struct g_geom *gp;
108	struct g_mbr_softc *mp;
109	struct g_slicer *gsp;
110	int index;
111
112	pp = bp->bio_to;
113	index = pp->index;
114	gp = pp->geom;
115	gsp = gp->softc;
116	mp = gsp->softc;
117	if (bp->bio_cmd == BIO_GETATTR) {
118		if (g_haveattr_int(bp, "MBR::type", mp->type[index]))
119			return (1);
120	}
121	return (0);
122}
123
124static void
125g_mbr_dumpconf(struct sbuf *sb, char *indent, struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp)
126{
127	struct g_mbr_softc *mp;
128	struct g_slicer *gsp;
129
130	g_slice_dumpconf(sb, indent, gp, cp, pp);
131	gsp = gp->softc;
132	mp = gsp->softc;
133	if (pp != NULL) {
134		sbuf_printf(sb, "%s<type>%d</type>\n",
135		    indent, mp->type[pp->index]);
136	}
137}
138
139
140static struct dos_partition historical_bogus_partition_table[NDOSPART] = {
141        { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
142        { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
143        { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
144        { 0x80, 0, 1, 0, DOSPTYP_386BSD, 255, 255, 255, 0, 50000, },
145};
146static struct dos_partition historical_bogus_partition_table_fixed[NDOSPART] = {
147        { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
148        { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
149        { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
150        { 0x80, 0, 1, 0, DOSPTYP_386BSD, 254, 255, 255, 0, 50000, },
151};
152
153static void
154g_mbr_print(int i __unused, struct dos_partition *dp __unused)
155{
156
157#if 0
158	g_hexdump(dp, sizeof(dp[0]));
159	printf("[%d] f:%02x typ:%d", i, dp->dp_flag, dp->dp_typ);
160	printf(" s(CHS):%d/%d/%d", dp->dp_scyl, dp->dp_shd, dp->dp_ssect);
161	printf(" e(CHS):%d/%d/%d", dp->dp_ecyl, dp->dp_ehd, dp->dp_esect);
162	printf(" s:%d l:%d\n", dp->dp_start, dp->dp_size);
163#endif
164}
165
166static struct g_geom *
167g_mbr_taste(struct g_class *mp, struct g_provider *pp, int insist)
168{
169	struct g_geom *gp;
170	struct g_consumer *cp;
171	struct g_provider *pp2;
172	int error, i, npart;
173	struct dos_partition dp[NDOSPART];
174	struct g_mbr_softc *ms;
175	struct g_slicer *gsp;
176	u_int fwsectors, sectorsize;
177	u_char *buf;
178
179	g_trace(G_T_TOPOLOGY, "mbr_taste(%s,%s)", mp->name, pp->name);
180	g_topology_assert();
181	gp = g_slice_new(mp, NDOSPART, pp, &cp, &ms, sizeof *ms, g_mbr_start);
182	if (gp == NULL)
183		return (NULL);
184	gsp = gp->softc;
185	g_topology_unlock();
186	gp->dumpconf = g_mbr_dumpconf;
187	npart = 0;
188	while (1) {	/* a trick to allow us to use break */
189		if (gp->rank != 2 && insist == 0)
190			break;
191		error = g_getattr("GEOM::fwsectors", cp, &fwsectors);
192		if (error)
193			fwsectors = 17;
194		error = g_getattr("GEOM::sectorsize", cp, &sectorsize);
195		if (error)
196			break;
197		if (!error && sectorsize != 512)
198			break;
199		gsp->frontstuff = sectorsize * fwsectors;
200		buf = g_read_data(cp, 0, sectorsize, &error);
201		if (buf == NULL || error != 0)
202			break;
203		if (buf[0x1fe] != 0x55 && buf[0x1ff] != 0xaa) {
204			g_free(buf);
205			break;
206		}
207		for (i = 0; i < NDOSPART; i++)
208			g_dec_dos_partition(
209			    buf + DOSPARTOFF + i * sizeof(struct dos_partition),
210			    dp + i);
211		g_free(buf);
212		if (bcmp(dp, historical_bogus_partition_table,
213		    sizeof historical_bogus_partition_table) == 0)
214			break;
215		if (bcmp(dp, historical_bogus_partition_table_fixed,
216		    sizeof historical_bogus_partition_table_fixed) == 0)
217			break;
218		npart = 0;
219		for (i = 0; i < NDOSPART; i++) {
220			if (dp[i].dp_flag != 0 && dp[i].dp_flag != 0x80)
221				continue;
222			if (dp[i].dp_size == 0)
223				continue;
224			g_mbr_print(i, dp + i);
225			npart++;
226			ms->type[i] = dp[i].dp_typ;
227			pp2 = g_slice_addslice(gp, i,
228			    ((off_t)dp[i].dp_start) << 9ULL,
229			    ((off_t)dp[i].dp_size) << 9ULL,
230			    "%ss%d", gp->name, i + 1);
231		}
232		break;
233	}
234	g_topology_lock();
235	error = g_access_rel(cp, -1, 0, 0);
236	if (npart > 0) {
237		g_new_magicspaces(gp, 3);
238		g_add_magicspace(gp, 0, "boot", 0, DOSPARTOFF, 0);
239		g_add_magicspace(gp, 1, "mbr", DOSPARTOFF, 4 * 16, 0);
240		g_add_magicspace(gp, 2, "signature", 510, 2, 0);
241		LIST_FOREACH(pp, &gp->provider, provider)
242			g_error_provider(pp, 0);
243		return (gp);
244	}
245	g_std_spoiled(cp);
246	return (NULL);
247}
248
249
250static struct g_class g_mbr_class	= {
251	MBR_CLASS_NAME,
252	g_mbr_taste,
253	NULL,
254	G_CLASS_INITSTUFF
255};
256
257DECLARE_GEOM_CLASS(g_mbr_class, g_mbr);
258
259#define NDOSEXTPART		32
260struct g_mbrext_softc {
261	int		type [NDOSEXTPART];
262};
263
264static int
265g_mbrext_start(struct bio *bp)
266{
267	struct g_provider *pp;
268	struct g_geom *gp;
269	struct g_mbrext_softc *mp;
270	struct g_slicer *gsp;
271	int index;
272
273	pp = bp->bio_to;
274	index = pp->index;
275	gp = pp->geom;
276	gsp = gp->softc;
277	mp = gsp->softc;
278	if (bp->bio_cmd == BIO_GETATTR) {
279		if (g_haveattr_int(bp, "MBR::type", mp->type[index]))
280			return (1);
281	}
282	return (0);
283}
284
285static void
286g_mbrext_dumpconf(struct sbuf *sb, char *indent, struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp)
287{
288	struct g_mbrext_softc *mp;
289	struct g_slicer *gsp;
290
291	g_slice_dumpconf(sb, indent, gp, cp, pp);
292	gsp = gp->softc;
293	mp = gsp->softc;
294	if (pp != NULL) {
295		sbuf_printf(sb, "%s<type>%d</type>\n",
296		    indent, mp->type[pp->index]);
297	}
298}
299
300static void
301g_mbrext_print(int i, struct dos_partition *dp)
302{
303	g_hexdump(dp, sizeof(dp[0]));
304	printf("[%d] f:%02x typ:%d", i, dp->dp_flag, dp->dp_typ);
305	printf(" s(CHS):%d/%d/%d", dp->dp_scyl, dp->dp_shd, dp->dp_ssect);
306	printf(" e(CHS):%d/%d/%d", dp->dp_ecyl, dp->dp_ehd, dp->dp_esect);
307	printf(" s:%d l:%d\n", dp->dp_start, dp->dp_size);
308}
309
310static struct g_geom *
311g_mbrext_taste(struct g_class *mp, struct g_provider *pp, int insist __unused)
312{
313	struct g_geom *gp;
314	struct g_consumer *cp;
315	struct g_provider *pp2;
316	int error, i, slice;
317	struct g_mbrext_softc *ms;
318	off_t off;
319	u_char *buf;
320	struct dos_partition dp[4];
321	u_int fwsectors, sectorsize;
322	struct g_slicer *gsp;
323
324	g_trace(G_T_TOPOLOGY, "g_mbrext_taste(%s,%s)", mp->name, pp->name);
325	g_topology_assert();
326	if (strcmp(pp->geom->class->name, MBR_CLASS_NAME))
327		return (NULL);
328	gp = g_slice_new(mp, NDOSEXTPART, pp, &cp, &ms, sizeof *ms, g_mbrext_start);
329	if (gp == NULL)
330		return (NULL);
331	gsp = gp->softc;
332	g_topology_unlock();
333	gp->dumpconf = g_mbrext_dumpconf;
334	off = 0;
335	slice = 0;
336	while (1) {	/* a trick to allow us to use break */
337		error = g_getattr("MBR::type", cp, &i);
338		if (error || i != DOSPTYP_EXT)
339			break;
340		error = g_getattr("GEOM::fwsectors", cp, &fwsectors);
341		if (error)
342			fwsectors = 17;
343		error = g_getattr("GEOM::sectorsize", cp, &sectorsize);
344		if (error)
345			break;
346		if (!error && sectorsize != 512)
347			break;
348		gsp->frontstuff = sectorsize * fwsectors;
349		for (;;) {
350			buf = g_read_data(cp, off, sectorsize, &error);
351			if (buf == NULL || error != 0)
352				break;
353			if (buf[0x1fe] != 0x55 && buf[0x1ff] != 0xaa)
354				break;
355			for (i = 0; i < NDOSPART; i++)
356				g_dec_dos_partition(
357				    buf + DOSPARTOFF + i * sizeof(struct dos_partition),
358				    dp + i);
359			g_free(buf);
360			g_mbrext_print(0, dp);
361			g_mbrext_print(1, dp + 1);
362			if (dp[0].dp_flag == 0 && dp[0].dp_size != 0) {
363				pp2 = g_slice_addslice(gp, slice,
364				    (((off_t)dp[0].dp_start) << 9ULL) + off,
365				    ((off_t)dp[0].dp_size) << 9ULL,
366				    "%*.*s%d",
367				    strlen(gp->name) - 1,
368				    strlen(gp->name) - 1,
369				    gp->name,
370				    slice + 5);
371				ms->type[slice] = dp[0].dp_typ;
372				slice++;
373				g_error_provider(pp2, 0);
374			}
375			if (dp[1].dp_flag != 0)
376				break;
377			if (dp[1].dp_typ != DOSPTYP_EXT)
378				break;
379			if (dp[1].dp_size == 0)
380				break;
381			off = ((off_t)dp[1].dp_start) << 9ULL;
382		}
383		break;
384	}
385	g_topology_lock();
386	error = g_access_rel(cp, -1, 0, 0);
387	if (slice > 0) {
388		/* XXX: add magic spaces */
389		return (gp);
390	}
391
392	g_topology_assert();
393	g_std_spoiled(cp);
394	g_topology_assert();
395	return (NULL);
396}
397
398
399static struct g_class g_mbrext_class	= {
400	MBREXT_CLASS_NAME,
401	g_mbrext_taste,
402	NULL,
403	G_CLASS_INITSTUFF
404};
405
406DECLARE_GEOM_CLASS(g_mbrext_class, g_mbrext);
407