35
36#include <sys/param.h>
37#include <sys/errno.h>
38#include <sys/endian.h>
39#include <sys/systm.h>
40#include <sys/sysctl.h>
41#include <sys/kernel.h>
42#include <sys/fcntl.h>
43#include <sys/malloc.h>
44#include <sys/bio.h>
45#include <sys/lock.h>
46#include <sys/mutex.h>
47#include <sys/md5.h>
48#include <sys/proc.h>
49
50#include <sys/diskmbr.h>
51#include <sys/sbuf.h>
52#include <geom/geom.h>
53#include <geom/geom_slice.h>
54
55FEATURE(geom_mbr, "GEOM DOS/MBR partitioning support");
56
57#define MBR_CLASS_NAME "MBR"
58#define MBREXT_CLASS_NAME "MBREXT"
59
60static struct dos_partition historical_bogus_partition_table[NDOSPART] = {
61 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
62 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
63 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
64 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 255, 255, 255, 0, 50000, },
65};
66
67static struct dos_partition historical_bogus_partition_table_fixed[NDOSPART] = {
68 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
69 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
70 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, },
71 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 254, 255, 255, 0, 50000, },
72};
73
74static void
75g_mbr_print(int i, struct dos_partition *dp)
76{
77
78 printf("[%d] f:%02x typ:%d", i, dp->dp_flag, dp->dp_typ);
79 printf(" s(CHS):%d/%d/%d", DPCYL(dp->dp_scyl, dp->dp_ssect),
80 dp->dp_shd, DPSECT(dp->dp_ssect));
81 printf(" e(CHS):%d/%d/%d", DPCYL(dp->dp_ecyl, dp->dp_esect),
82 dp->dp_ehd, DPSECT(dp->dp_esect));
83 printf(" s:%d l:%d\n", dp->dp_start, dp->dp_size);
84}
85
86struct g_mbr_softc {
87 int type [NDOSPART];
88 u_int sectorsize;
89 u_char sec0[512];
90 u_char slicesum[16];
91};
92
93/*
94 * XXX: Add gctl_req arg and give good error msgs.
95 * XXX: Check that length argument does not bring boot code inside any slice.
96 */
97static int
98g_mbr_modify(struct g_geom *gp, struct g_mbr_softc *ms, u_char *sec0, int len __unused)
99{
100 int i, error;
101 off_t l[NDOSPART];
102 struct dos_partition ndp[NDOSPART], *dp;
103 MD5_CTX md5sum;
104
105 g_topology_assert();
106
107 if (sec0[0x1fe] != 0x55 && sec0[0x1ff] != 0xaa)
108 return (EBUSY);
109
110 dp = ndp;
111 for (i = 0; i < NDOSPART; i++) {
112 dos_partition_dec(
113 sec0 + DOSPARTOFF + i * sizeof(struct dos_partition),
114 dp + i);
115 }
116 if ((!bcmp(dp, historical_bogus_partition_table,
117 sizeof historical_bogus_partition_table)) ||
118 (!bcmp(dp, historical_bogus_partition_table_fixed,
119 sizeof historical_bogus_partition_table_fixed))) {
120 /*
121 * We will not allow people to write these from "the inside",
122 * Since properly selfdestructing takes too much code. If
123 * people really want to do this, they cannot have any
124 * providers of this geom open, and in that case they can just
125 * as easily overwrite the MBR in the parent device.
126 */
127 return(EBUSY);
128 }
129 for (i = 0; i < NDOSPART; i++) {
130 /*
131 * A Protective MBR (PMBR) has a single partition of
132 * type 0xEE spanning the whole disk. Such a MBR
133 * protects a GPT on the disk from MBR tools that
134 * don't know anything about GPT. We're interpreting
135 * it a bit more loosely: any partition of type 0xEE
136 * is to be skipped as it doesn't contain any data
137 * that we should care about. We still allow other
138 * partitions to be present in the MBR. A PMBR will
139 * be handled correctly anyway.
140 */
141 if (dp[i].dp_typ == DOSPTYP_PMBR)
142 l[i] = 0;
143 else if (dp[i].dp_flag != 0 && dp[i].dp_flag != 0x80)
144 l[i] = 0;
145 else if (dp[i].dp_typ == 0)
146 l[i] = 0;
147 else
148 l[i] = (off_t)dp[i].dp_size * ms->sectorsize;
149 error = g_slice_config(gp, i, G_SLICE_CONFIG_CHECK,
150 (off_t)dp[i].dp_start * ms->sectorsize, l[i],
151 ms->sectorsize, "%ss%d", gp->name, 1 + i);
152 if (error)
153 return (error);
154 }
155 for (i = 0; i < NDOSPART; i++) {
156 ms->type[i] = dp[i].dp_typ;
157 g_slice_config(gp, i, G_SLICE_CONFIG_SET,
158 (off_t)dp[i].dp_start * ms->sectorsize, l[i],
159 ms->sectorsize, "%ss%d", gp->name, 1 + i);
160 }
161 bcopy(sec0, ms->sec0, 512);
162
163 /*
164 * Calculate MD5 from the first sector and use it for avoiding
165 * recursive slices creation.
166 */
167 MD5Init(&md5sum);
168 MD5Update(&md5sum, ms->sec0, sizeof(ms->sec0));
169 MD5Final(ms->slicesum, &md5sum);
170
171 return (0);
172}
173
174static int
175g_mbr_ioctl(struct g_provider *pp, u_long cmd, void *data, int fflag, struct thread *td)
176{
177 struct g_geom *gp;
178 struct g_mbr_softc *ms;
179 struct g_slicer *gsp;
180 struct g_consumer *cp;
181 int error, opened;
182
183 gp = pp->geom;
184 gsp = gp->softc;
185 ms = gsp->softc;
186
187 opened = 0;
188 error = 0;
189 switch(cmd) {
190 case DIOCSMBR: {
191 if (!(fflag & FWRITE))
192 return (EPERM);
193 DROP_GIANT();
194 g_topology_lock();
195 cp = LIST_FIRST(&gp->consumer);
196 if (cp->acw == 0) {
197 error = g_access(cp, 0, 1, 0);
198 if (error == 0)
199 opened = 1;
200 }
201 if (!error)
202 error = g_mbr_modify(gp, ms, data, 512);
203 if (!error)
204 error = g_write_data(cp, 0, data, 512);
205 if (opened)
206 g_access(cp, 0, -1 , 0);
207 g_topology_unlock();
208 PICKUP_GIANT();
209 return(error);
210 }
211 default:
212 return (ENOIOCTL);
213 }
214}
215
216static int
217g_mbr_start(struct bio *bp)
218{
219 struct g_provider *pp;
220 struct g_geom *gp;
221 struct g_mbr_softc *mp;
222 struct g_slicer *gsp;
223 int idx;
224
225 pp = bp->bio_to;
226 idx = pp->index;
227 gp = pp->geom;
228 gsp = gp->softc;
229 mp = gsp->softc;
230 if (bp->bio_cmd == BIO_GETATTR) {
231 if (g_handleattr_int(bp, "MBR::type", mp->type[idx]))
232 return (1);
233 if (g_handleattr_off_t(bp, "MBR::offset",
234 gsp->slices[idx].offset))
235 return (1);
236 if (g_handleattr(bp, "MBR::slicesum", mp->slicesum,
237 sizeof(mp->slicesum)))
238 return (1);
239 }
240
241 return (0);
242}
243
244static void
245g_mbr_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp)
246{
247 struct g_mbr_softc *mp;
248 struct g_slicer *gsp;
249
250 gsp = gp->softc;
251 mp = gsp->softc;
252 g_slice_dumpconf(sb, indent, gp, cp, pp);
253 if (pp != NULL) {
254 if (indent == NULL)
255 sbuf_printf(sb, " ty %d", mp->type[pp->index]);
256 else
257 sbuf_printf(sb, "%s<type>%d</type>\n", indent,
258 mp->type[pp->index]);
259 }
260}
261
262static struct g_geom *
263g_mbr_taste(struct g_class *mp, struct g_provider *pp, int insist)
264{
265 struct g_geom *gp;
266 struct g_consumer *cp;
267 int error;
268 struct g_mbr_softc *ms;
269 u_int fwsectors, sectorsize;
270 u_char *buf;
271 u_char hash[16];
272 MD5_CTX md5sum;
273
274 g_trace(G_T_TOPOLOGY, "mbr_taste(%s,%s)", mp->name, pp->name);
275 g_topology_assert();
276 if (!strcmp(pp->geom->class->name, MBR_CLASS_NAME))
277 return (NULL);
278 gp = g_slice_new(mp, NDOSPART, pp, &cp, &ms, sizeof *ms, g_mbr_start);
279 if (gp == NULL)
280 return (NULL);
281 g_topology_unlock();
282 do {
283 error = g_getattr("GEOM::fwsectors", cp, &fwsectors);
284 if (error)
285 fwsectors = 17;
286 sectorsize = cp->provider->sectorsize;
287 if (sectorsize < 512)
288 break;
289 ms->sectorsize = sectorsize;
290 buf = g_read_data(cp, 0, sectorsize, NULL);
291 if (buf == NULL)
292 break;
293
294 /*
295 * Calculate MD5 from the first sector and use it for avoiding
296 * recursive slices creation.
297 */
298 bcopy(buf, ms->sec0, 512);
299 MD5Init(&md5sum);
300 MD5Update(&md5sum, ms->sec0, sizeof(ms->sec0));
301 MD5Final(ms->slicesum, &md5sum);
302
303 error = g_getattr("MBR::slicesum", cp, &hash);
304 if (!error && !bcmp(ms->slicesum, hash, sizeof(hash))) {
305 g_free(buf);
306 break;
307 }
308
309 g_topology_lock();
310 g_mbr_modify(gp, ms, buf, 512);
311 g_topology_unlock();
312 g_free(buf);
313 break;
314 } while (0);
315 g_topology_lock();
316 g_access(cp, -1, 0, 0);
317 if (LIST_EMPTY(&gp->provider)) {
318 g_slice_spoiled(cp);
319 return (NULL);
320 }
321 return (gp);
322}
323
324static void
325g_mbr_config(struct gctl_req *req, struct g_class *mp, const char *verb)
326{
327 struct g_geom *gp;
328 struct g_consumer *cp;
329 struct g_mbr_softc *ms;
330 struct g_slicer *gsp;
331 int opened = 0, error = 0;
332 void *data;
333 int len;
334
335 g_topology_assert();
336 gp = gctl_get_geom(req, mp, "geom");
337 if (gp == NULL)
338 return;
339 if (strcmp(verb, "write MBR")) {
340 gctl_error(req, "Unknown verb");
341 return;
342 }
343 gsp = gp->softc;
344 ms = gsp->softc;
345 data = gctl_get_param(req, "data", &len);
346 if (data == NULL)
347 return;
348 if (len < 512 || (len % 512)) {
349 gctl_error(req, "Wrong request length");
350 return;
351 }
352 cp = LIST_FIRST(&gp->consumer);
353 if (cp->acw == 0) {
354 error = g_access(cp, 0, 1, 0);
355 if (error == 0)
356 opened = 1;
357 }
358 if (!error)
359 error = g_mbr_modify(gp, ms, data, len);
360 if (error)
361 gctl_error(req, "conflict with open slices");
362 if (!error)
363 error = g_write_data(cp, 0, data, len);
364 if (error)
365 gctl_error(req, "sector zero write failed");
366 if (opened)
367 g_access(cp, 0, -1 , 0);
368 return;
369}
370
371static struct g_class g_mbr_class = {
372 .name = MBR_CLASS_NAME,
373 .version = G_VERSION,
374 .taste = g_mbr_taste,
375 .dumpconf = g_mbr_dumpconf,
376 .ctlreq = g_mbr_config,
377 .ioctl = g_mbr_ioctl,
378};
379
380DECLARE_GEOM_CLASS(g_mbr_class, g_mbr);
381
382#define NDOSEXTPART 32
383struct g_mbrext_softc {
384 int type [NDOSEXTPART];
385};
386
387static int
388g_mbrext_start(struct bio *bp)
389{
390 struct g_provider *pp;
391 struct g_geom *gp;
392 struct g_mbrext_softc *mp;
393 struct g_slicer *gsp;
394 int idx;
395
396 pp = bp->bio_to;
397 idx = pp->index;
398 gp = pp->geom;
399 gsp = gp->softc;
400 mp = gsp->softc;
401 if (bp->bio_cmd == BIO_GETATTR) {
402 if (g_handleattr_int(bp, "MBR::type", mp->type[idx]))
403 return (1);
404 }
405 return (0);
406}
407
408static void
409g_mbrext_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp)
410{
411 struct g_mbrext_softc *mp;
412 struct g_slicer *gsp;
413
414 g_slice_dumpconf(sb, indent, gp, cp, pp);
415 gsp = gp->softc;
416 mp = gsp->softc;
417 if (pp != NULL) {
418 if (indent == NULL)
419 sbuf_printf(sb, " ty %d", mp->type[pp->index]);
420 else
421 sbuf_printf(sb, "%s<type>%d</type>\n", indent,
422 mp->type[pp->index]);
423 }
424}
425
426static struct g_geom *
427g_mbrext_taste(struct g_class *mp, struct g_provider *pp, int insist __unused)
428{
429 struct g_geom *gp;
430 struct g_consumer *cp;
431 int error, i, slice;
432 struct g_mbrext_softc *ms;
433 off_t off;
434 u_char *buf;
435 struct dos_partition dp[4];
436 u_int fwsectors, sectorsize;
437
438 g_trace(G_T_TOPOLOGY, "g_mbrext_taste(%s,%s)", mp->name, pp->name);
439 g_topology_assert();
440 if (strcmp(pp->geom->class->name, MBR_CLASS_NAME))
441 return (NULL);
442 gp = g_slice_new(mp, NDOSEXTPART, pp, &cp, &ms, sizeof *ms,
443 g_mbrext_start);
444 if (gp == NULL)
445 return (NULL);
446 g_topology_unlock();
447 off = 0;
448 slice = 0;
449 do {
450 error = g_getattr("MBR::type", cp, &i);
451 if (error || (i != DOSPTYP_EXT && i != DOSPTYP_EXTLBA))
452 break;
453 error = g_getattr("GEOM::fwsectors", cp, &fwsectors);
454 if (error)
455 fwsectors = 17;
456 sectorsize = cp->provider->sectorsize;
457 if (sectorsize != 512)
458 break;
459 for (;;) {
460 buf = g_read_data(cp, off, sectorsize, NULL);
461 if (buf == NULL)
462 break;
463 if (buf[0x1fe] != 0x55 && buf[0x1ff] != 0xaa) {
464 g_free(buf);
465 break;
466 }
467 for (i = 0; i < NDOSPART; i++)
468 dos_partition_dec(
469 buf + DOSPARTOFF +
470 i * sizeof(struct dos_partition), dp + i);
471 g_free(buf);
472 if (0 && bootverbose) {
473 printf("MBREXT Slice %d on %s:\n",
474 slice + 5, gp->name);
475 g_mbr_print(0, dp);
476 g_mbr_print(1, dp + 1);
477 }
478 if ((dp[0].dp_flag & 0x7f) == 0 &&
479 dp[0].dp_size != 0 && dp[0].dp_typ != 0) {
480 g_topology_lock();
481 g_slice_config(gp, slice, G_SLICE_CONFIG_SET,
482 (((off_t)dp[0].dp_start) << 9ULL) + off,
483 ((off_t)dp[0].dp_size) << 9ULL,
484 sectorsize,
485 "%*.*s%d",
|