xref: /freebsd/sys/geom/label/g_label.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 2004-2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_geom.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/lock.h>
37 #include <sys/mutex.h>
38 #include <sys/bio.h>
39 #include <sys/ctype.h>
40 #include <sys/malloc.h>
41 #include <sys/libkern.h>
42 #include <sys/sbuf.h>
43 #include <sys/stddef.h>
44 #include <sys/sysctl.h>
45 #include <geom/geom.h>
46 #include <geom/geom_slice.h>
47 #include <geom/label/g_label.h>
48 
49 FEATURE(geom_label, "GEOM labeling support");
50 
51 SYSCTL_DECL(_kern_geom);
52 SYSCTL_NODE(_kern_geom, OID_AUTO, label, CTLFLAG_RW, 0, "GEOM_LABEL stuff");
53 u_int g_label_debug = 0;
54 SYSCTL_UINT(_kern_geom_label, OID_AUTO, debug, CTLFLAG_RWTUN, &g_label_debug, 0,
55     "Debug level");
56 
57 static int g_label_destroy_geom(struct gctl_req *req, struct g_class *mp,
58     struct g_geom *gp);
59 static int g_label_destroy(struct g_geom *gp, boolean_t force);
60 static struct g_geom *g_label_taste(struct g_class *mp, struct g_provider *pp,
61     int flags __unused);
62 static void g_label_config(struct gctl_req *req, struct g_class *mp,
63     const char *verb);
64 
65 struct g_class g_label_class = {
66 	.name = G_LABEL_CLASS_NAME,
67 	.version = G_VERSION,
68 	.ctlreq = g_label_config,
69 	.taste = g_label_taste,
70 	.destroy_geom = g_label_destroy_geom
71 };
72 
73 /*
74  * To add a new file system where you want to look for volume labels,
75  * you have to:
76  * 1. Add a file g_label_<file system>.c which implements labels recognition.
77  * 2. Add an 'extern const struct g_label_desc g_label_<file system>;' into
78  *    g_label.h file.
79  * 3. Add an element to the table below '&g_label_<file system>,'.
80  * 4. Add your file to sys/conf/files.
81  * 5. Add your file to sys/modules/geom/geom_label/Makefile.
82  * 6. Add your file system to manual page sbin/geom/class/label/glabel.8.
83  */
84 const struct g_label_desc *g_labels[] = {
85 	&g_label_gpt,
86 	&g_label_gpt_uuid,
87 #ifdef GEOM_LABEL
88 	&g_label_ufs_id,
89 	&g_label_ufs_volume,
90 	&g_label_iso9660,
91 	&g_label_msdosfs,
92 	&g_label_ext2fs,
93 	&g_label_reiserfs,
94 	&g_label_ntfs,
95 	&g_label_disk_ident,
96 #endif
97 	NULL
98 };
99 
100 void
101 g_label_rtrim(char *label, size_t size)
102 {
103 	ptrdiff_t i;
104 
105 	for (i = size - 1; i >= 0; i--) {
106 		if (label[i] == '\0')
107 			continue;
108 		else if (label[i] == ' ')
109 			label[i] = '\0';
110 		else
111 			break;
112 	}
113 }
114 
115 static int
116 g_label_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
117     struct g_geom *gp __unused)
118 {
119 
120 	/*
121 	 * XXX: Unloading a class which is using geom_slice:1.56 is currently
122 	 * XXX: broken, so we deny unloading when we have geoms.
123 	 */
124 	return (EOPNOTSUPP);
125 }
126 
127 static void
128 g_label_orphan(struct g_consumer *cp)
129 {
130 
131 	G_LABEL_DEBUG(1, "Label %s removed.",
132 	    LIST_FIRST(&cp->geom->provider)->name);
133 	g_slice_orphan(cp);
134 }
135 
136 static void
137 g_label_spoiled(struct g_consumer *cp)
138 {
139 
140 	G_LABEL_DEBUG(1, "Label %s removed.",
141 	    LIST_FIRST(&cp->geom->provider)->name);
142 	g_slice_spoiled(cp);
143 }
144 
145 static void
146 g_label_resize(struct g_consumer *cp)
147 {
148 
149 	G_LABEL_DEBUG(1, "Label %s resized.",
150 	    LIST_FIRST(&cp->geom->provider)->name);
151 
152 	g_slice_config(cp->geom, 0, G_SLICE_CONFIG_FORCE, (off_t)0,
153 	    cp->provider->mediasize, cp->provider->sectorsize, "notused");
154 }
155 
156 static int
157 g_label_is_name_ok(const char *label)
158 {
159 	const char *s;
160 
161 	/* Check if the label starts from ../ */
162 	if (strncmp(label, "../", 3) == 0)
163 		return (0);
164 	/* Check if the label contains /../ */
165 	if (strstr(label, "/../") != NULL)
166 		return (0);
167 	/* Check if the label ends at ../ */
168 	if ((s = strstr(label, "/..")) != NULL && s[3] == '\0')
169 		return (0);
170 	return (1);
171 }
172 
173 static void
174 g_label_mangle_name(char *label, size_t size)
175 {
176 	struct sbuf *sb;
177 	const u_char *c;
178 
179 	sb = sbuf_new(NULL, NULL, size, SBUF_FIXEDLEN);
180 	for (c = label; *c != '\0'; c++) {
181 		if (!isprint(*c) || isspace(*c) || *c =='"' || *c == '%')
182 			sbuf_printf(sb, "%%%02X", *c);
183 		else
184 			sbuf_putc(sb, *c);
185 	}
186 	if (sbuf_finish(sb) != 0)
187 		label[0] = '\0';
188 	else
189 		strlcpy(label, sbuf_data(sb), size);
190 	sbuf_delete(sb);
191 }
192 
193 static struct g_geom *
194 g_label_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
195     const char *label, const char *dir, off_t mediasize)
196 {
197 	struct g_geom *gp;
198 	struct g_provider *pp2;
199 	struct g_consumer *cp;
200 	char name[64];
201 
202 	g_topology_assert();
203 
204 	if (!g_label_is_name_ok(label)) {
205 		G_LABEL_DEBUG(0, "%s contains suspicious label, skipping.",
206 		    pp->name);
207 		G_LABEL_DEBUG(1, "%s suspicious label is: %s", pp->name, label);
208 		if (req != NULL)
209 			gctl_error(req, "Label name %s is invalid.", label);
210 		return (NULL);
211 	}
212 	gp = NULL;
213 	cp = NULL;
214 	snprintf(name, sizeof(name), "%s/%s", dir, label);
215 	LIST_FOREACH(gp, &mp->geom, geom) {
216 		pp2 = LIST_FIRST(&gp->provider);
217 		if (pp2 == NULL)
218 			continue;
219 		if ((pp2->flags & G_PF_ORPHAN) != 0)
220 			continue;
221 		if (strcmp(pp2->name, name) == 0) {
222 			G_LABEL_DEBUG(1, "Label %s(%s) already exists (%s).",
223 			    label, name, pp->name);
224 			if (req != NULL) {
225 				gctl_error(req, "Provider %s already exists.",
226 				    name);
227 			}
228 			return (NULL);
229 		}
230 	}
231 	gp = g_slice_new(mp, 1, pp, &cp, NULL, 0, NULL);
232 	if (gp == NULL) {
233 		G_LABEL_DEBUG(0, "Cannot create slice %s.", label);
234 		if (req != NULL)
235 			gctl_error(req, "Cannot create slice %s.", label);
236 		return (NULL);
237 	}
238 	gp->orphan = g_label_orphan;
239 	gp->spoiled = g_label_spoiled;
240 	gp->resize = g_label_resize;
241 	g_access(cp, -1, 0, 0);
242 	g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t)0, mediasize,
243 	    pp->sectorsize, "%s", name);
244 	G_LABEL_DEBUG(1, "Label for provider %s is %s.", pp->name, name);
245 	return (gp);
246 }
247 
248 static int
249 g_label_destroy(struct g_geom *gp, boolean_t force)
250 {
251 	struct g_provider *pp;
252 
253 	g_topology_assert();
254 	pp = LIST_FIRST(&gp->provider);
255 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
256 		if (force) {
257 			G_LABEL_DEBUG(0, "Provider %s is still open, so it "
258 			    "can't be definitely removed.", pp->name);
259 		} else {
260 			G_LABEL_DEBUG(1,
261 			    "Provider %s is still open (r%dw%de%d).", pp->name,
262 			    pp->acr, pp->acw, pp->ace);
263 			return (EBUSY);
264 		}
265 	} else if (pp != NULL)
266 		G_LABEL_DEBUG(1, "Label %s removed.", pp->name);
267 	g_slice_spoiled(LIST_FIRST(&gp->consumer));
268 	return (0);
269 }
270 
271 static int
272 g_label_read_metadata(struct g_consumer *cp, struct g_label_metadata *md)
273 {
274 	struct g_provider *pp;
275 	u_char *buf;
276 	int error;
277 
278 	g_topology_assert();
279 
280 	pp = cp->provider;
281 	g_topology_unlock();
282 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
283 	    &error);
284 	g_topology_lock();
285 	if (buf == NULL)
286 		return (error);
287 	/* Decode metadata. */
288 	label_metadata_decode(buf, md);
289 	g_free(buf);
290 
291 	return (0);
292 }
293 
294 static void
295 g_label_orphan_taste(struct g_consumer *cp __unused)
296 {
297 
298 	KASSERT(1 == 0, ("%s called?", __func__));
299 }
300 
301 static void
302 g_label_start_taste(struct bio *bp __unused)
303 {
304 
305 	KASSERT(1 == 0, ("%s called?", __func__));
306 }
307 
308 static int
309 g_label_access_taste(struct g_provider *pp __unused, int dr __unused,
310     int dw __unused, int de __unused)
311 {
312 
313 	KASSERT(1 == 0, ("%s called", __func__));
314 	return (EOPNOTSUPP);
315 }
316 
317 static struct g_geom *
318 g_label_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
319 {
320 	struct g_label_metadata md;
321 	struct g_consumer *cp;
322 	struct g_geom *gp;
323 	int i;
324 
325 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
326 	g_topology_assert();
327 
328 	G_LABEL_DEBUG(2, "Tasting %s.", pp->name);
329 
330 	/* Skip providers that are already open for writing. */
331 	if (pp->acw > 0)
332 		return (NULL);
333 
334 	if (strcmp(pp->geom->class->name, mp->name) == 0)
335 		return (NULL);
336 
337 	gp = g_new_geomf(mp, "label:taste");
338 	gp->start = g_label_start_taste;
339 	gp->access = g_label_access_taste;
340 	gp->orphan = g_label_orphan_taste;
341 	cp = g_new_consumer(gp);
342 	g_attach(cp, pp);
343 	if (g_access(cp, 1, 0, 0) != 0)
344 		goto end;
345 	do {
346 		if (g_label_read_metadata(cp, &md) != 0)
347 			break;
348 		if (strcmp(md.md_magic, G_LABEL_MAGIC) != 0)
349 			break;
350 		if (md.md_version > G_LABEL_VERSION) {
351 			printf("geom_label.ko module is too old to handle %s.\n",
352 			    pp->name);
353 			break;
354 		}
355 
356 		/*
357 		 * Backward compatibility:
358 		 */
359 		/*
360 		 * There was no md_provsize field in earlier versions of
361 		 * metadata.
362 		 */
363 		if (md.md_version < 2)
364 			md.md_provsize = pp->mediasize;
365 
366 		if (md.md_provsize != pp->mediasize)
367 			break;
368 
369 		g_label_create(NULL, mp, pp, md.md_label, G_LABEL_DIR,
370 		    pp->mediasize - pp->sectorsize);
371 	} while (0);
372 	for (i = 0; g_labels[i] != NULL; i++) {
373 		char label[128];
374 
375 		if (g_labels[i]->ld_enabled == 0)
376 			continue;
377 		g_topology_unlock();
378 		g_labels[i]->ld_taste(cp, label, sizeof(label));
379 		g_label_mangle_name(label, sizeof(label));
380 		g_topology_lock();
381 		if (label[0] == '\0')
382 			continue;
383 		g_label_create(NULL, mp, pp, label, g_labels[i]->ld_dir,
384 		    pp->mediasize);
385 	}
386 	g_access(cp, -1, 0, 0);
387 end:
388 	g_detach(cp);
389 	g_destroy_consumer(cp);
390 	g_destroy_geom(gp);
391 	return (NULL);
392 }
393 
394 static void
395 g_label_ctl_create(struct gctl_req *req, struct g_class *mp)
396 {
397 	struct g_provider *pp;
398 	const char *name;
399 	int *nargs;
400 
401 	g_topology_assert();
402 
403 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
404 	if (nargs == NULL) {
405 		gctl_error(req, "No '%s' argument", "nargs");
406 		return;
407 	}
408 	if (*nargs != 2) {
409 		gctl_error(req, "Invalid number of arguments.");
410 		return;
411 	}
412 	/*
413 	 * arg1 is the name of provider.
414 	 */
415 	name = gctl_get_asciiparam(req, "arg1");
416 	if (name == NULL) {
417 		gctl_error(req, "No 'arg%d' argument", 1);
418 		return;
419 	}
420 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
421 		name += strlen("/dev/");
422 	pp = g_provider_by_name(name);
423 	if (pp == NULL) {
424 		G_LABEL_DEBUG(1, "Provider %s is invalid.", name);
425 		gctl_error(req, "Provider %s is invalid.", name);
426 		return;
427 	}
428 	/*
429 	 * arg0 is the label.
430 	 */
431 	name = gctl_get_asciiparam(req, "arg0");
432 	if (name == NULL) {
433 		gctl_error(req, "No 'arg%d' argument", 0);
434 		return;
435 	}
436 	g_label_create(req, mp, pp, name, G_LABEL_DIR, pp->mediasize);
437 }
438 
439 static const char *
440 g_label_skip_dir(const char *name)
441 {
442 	char path[64];
443 	u_int i;
444 
445 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
446 		name += strlen("/dev/");
447 	if (strncmp(name, G_LABEL_DIR "/", strlen(G_LABEL_DIR "/")) == 0)
448 		name += strlen(G_LABEL_DIR "/");
449 	for (i = 0; g_labels[i] != NULL; i++) {
450 		snprintf(path, sizeof(path), "%s/", g_labels[i]->ld_dir);
451 		if (strncmp(name, path, strlen(path)) == 0) {
452 			name += strlen(path);
453 			break;
454 		}
455 	}
456 	return (name);
457 }
458 
459 static struct g_geom *
460 g_label_find_geom(struct g_class *mp, const char *name)
461 {
462 	struct g_geom *gp;
463 	struct g_provider *pp;
464 	const char *pname;
465 
466 	name = g_label_skip_dir(name);
467 	LIST_FOREACH(gp, &mp->geom, geom) {
468 		pp = LIST_FIRST(&gp->provider);
469 		pname = g_label_skip_dir(pp->name);
470 		if (strcmp(pname, name) == 0)
471 			return (gp);
472 	}
473 	return (NULL);
474 }
475 
476 static void
477 g_label_ctl_destroy(struct gctl_req *req, struct g_class *mp)
478 {
479 	int *nargs, *force, error, i;
480 	struct g_geom *gp;
481 	const char *name;
482 	char param[16];
483 
484 	g_topology_assert();
485 
486 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
487 	if (nargs == NULL) {
488 		gctl_error(req, "No '%s' argument", "nargs");
489 		return;
490 	}
491 	if (*nargs <= 0) {
492 		gctl_error(req, "Missing device(s).");
493 		return;
494 	}
495 	force = gctl_get_paraml(req, "force", sizeof(*force));
496 	if (force == NULL) {
497 		gctl_error(req, "No 'force' argument");
498 		return;
499 	}
500 
501 	for (i = 0; i < *nargs; i++) {
502 		snprintf(param, sizeof(param), "arg%d", i);
503 		name = gctl_get_asciiparam(req, param);
504 		if (name == NULL) {
505 			gctl_error(req, "No 'arg%d' argument", i);
506 			return;
507 		}
508 		gp = g_label_find_geom(mp, name);
509 		if (gp == NULL) {
510 			G_LABEL_DEBUG(1, "Label %s is invalid.", name);
511 			gctl_error(req, "Label %s is invalid.", name);
512 			return;
513 		}
514 		error = g_label_destroy(gp, *force);
515 		if (error != 0) {
516 			gctl_error(req, "Cannot destroy label %s (error=%d).",
517 			    LIST_FIRST(&gp->provider)->name, error);
518 			return;
519 		}
520 	}
521 }
522 
523 static void
524 g_label_config(struct gctl_req *req, struct g_class *mp, const char *verb)
525 {
526 	uint32_t *version;
527 
528 	g_topology_assert();
529 
530 	version = gctl_get_paraml(req, "version", sizeof(*version));
531 	if (version == NULL) {
532 		gctl_error(req, "No '%s' argument.", "version");
533 		return;
534 	}
535 	if (*version != G_LABEL_VERSION) {
536 		gctl_error(req, "Userland and kernel parts are out of sync.");
537 		return;
538 	}
539 
540 	if (strcmp(verb, "create") == 0) {
541 		g_label_ctl_create(req, mp);
542 		return;
543 	} else if (strcmp(verb, "destroy") == 0 ||
544 	    strcmp(verb, "stop") == 0) {
545 		g_label_ctl_destroy(req, mp);
546 		return;
547 	}
548 
549 	gctl_error(req, "Unknown verb.");
550 }
551 
552 DECLARE_GEOM_CLASS(g_label_class, g_label);
553