xref: /freebsd/sys/geom/label/g_label.c (revision 7431dfd4580e850375fe5478d92ec770344db098)
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/sysctl.h>
44 #include <geom/geom.h>
45 #include <geom/geom_slice.h>
46 #include <geom/label/g_label.h>
47 
48 FEATURE(geom_label, "GEOM labeling support");
49 
50 SYSCTL_DECL(_kern_geom);
51 SYSCTL_NODE(_kern_geom, OID_AUTO, label, CTLFLAG_RW, 0, "GEOM_LABEL stuff");
52 u_int g_label_debug = 0;
53 SYSCTL_UINT(_kern_geom_label, OID_AUTO, debug, CTLFLAG_RWTUN, &g_label_debug, 0,
54     "Debug level");
55 
56 static int g_label_destroy_geom(struct gctl_req *req, struct g_class *mp,
57     struct g_geom *gp);
58 static int g_label_destroy(struct g_geom *gp, boolean_t force);
59 static struct g_geom *g_label_taste(struct g_class *mp, struct g_provider *pp,
60     int flags __unused);
61 static void g_label_config(struct gctl_req *req, struct g_class *mp,
62     const char *verb);
63 
64 struct g_class g_label_class = {
65 	.name = G_LABEL_CLASS_NAME,
66 	.version = G_VERSION,
67 	.ctlreq = g_label_config,
68 	.taste = g_label_taste,
69 	.destroy_geom = g_label_destroy_geom
70 };
71 
72 /*
73  * To add a new file system where you want to look for volume labels,
74  * you have to:
75  * 1. Add a file g_label_<file system>.c which implements labels recognition.
76  * 2. Add an 'extern const struct g_label_desc g_label_<file system>;' into
77  *    g_label.h file.
78  * 3. Add an element to the table below '&g_label_<file system>,'.
79  * 4. Add your file to sys/conf/files.
80  * 5. Add your file to sys/modules/geom/geom_label/Makefile.
81  * 6. Add your file system to manual page sbin/geom/class/label/glabel.8.
82  */
83 const struct g_label_desc *g_labels[] = {
84 	&g_label_gpt,
85 	&g_label_gpt_uuid,
86 #ifdef GEOM_LABEL
87 	&g_label_ufs_id,
88 	&g_label_ufs_volume,
89 	&g_label_iso9660,
90 	&g_label_msdosfs,
91 	&g_label_ext2fs,
92 	&g_label_reiserfs,
93 	&g_label_ntfs,
94 	&g_label_disk_ident,
95 #endif
96 	NULL
97 };
98 
99 
100 static int
101 g_label_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
102     struct g_geom *gp __unused)
103 {
104 
105 	/*
106 	 * XXX: Unloading a class which is using geom_slice:1.56 is currently
107 	 * XXX: broken, so we deny unloading when we have geoms.
108 	 */
109 	return (EOPNOTSUPP);
110 }
111 
112 static void
113 g_label_orphan(struct g_consumer *cp)
114 {
115 
116 	G_LABEL_DEBUG(1, "Label %s removed.",
117 	    LIST_FIRST(&cp->geom->provider)->name);
118 	g_slice_orphan(cp);
119 }
120 
121 static void
122 g_label_spoiled(struct g_consumer *cp)
123 {
124 
125 	G_LABEL_DEBUG(1, "Label %s removed.",
126 	    LIST_FIRST(&cp->geom->provider)->name);
127 	g_slice_spoiled(cp);
128 }
129 
130 static void
131 g_label_resize(struct g_consumer *cp)
132 {
133 
134 	G_LABEL_DEBUG(1, "Label %s resized.",
135 	    LIST_FIRST(&cp->geom->provider)->name);
136 
137 	g_slice_config(cp->geom, 0, G_SLICE_CONFIG_FORCE, (off_t)0,
138 	    cp->provider->mediasize, cp->provider->sectorsize, "notused");
139 }
140 
141 static int
142 g_label_is_name_ok(const char *label)
143 {
144 	const char *s;
145 
146 	/* Check if the label starts from ../ */
147 	if (strncmp(label, "../", 3) == 0)
148 		return (0);
149 	/* Check if the label contains /../ */
150 	if (strstr(label, "/../") != NULL)
151 		return (0);
152 	/* Check if the label ends at ../ */
153 	if ((s = strstr(label, "/..")) != NULL && s[3] == '\0')
154 		return (0);
155 	return (1);
156 }
157 
158 static void
159 g_label_mangle_name(char *label, size_t size)
160 {
161 	struct sbuf *sb;
162 	const u_char *c;
163 
164 	sb = sbuf_new(NULL, NULL, size, SBUF_FIXEDLEN);
165 	for (c = label; *c != '\0'; c++) {
166 		if (!isprint(*c) || isspace(*c) || *c =='"' || *c == '%')
167 			sbuf_printf(sb, "%%%02X", *c);
168 		else
169 			sbuf_putc(sb, *c);
170 	}
171 	if (sbuf_finish(sb) != 0)
172 		label[0] = '\0';
173 	else
174 		strlcpy(label, sbuf_data(sb), size);
175 	sbuf_delete(sb);
176 }
177 
178 static struct g_geom *
179 g_label_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
180     const char *label, const char *dir, off_t mediasize)
181 {
182 	struct g_geom *gp;
183 	struct g_provider *pp2;
184 	struct g_consumer *cp;
185 	char name[64];
186 
187 	g_topology_assert();
188 
189 	if (!g_label_is_name_ok(label)) {
190 		G_LABEL_DEBUG(0, "%s contains suspicious label, skipping.",
191 		    pp->name);
192 		G_LABEL_DEBUG(1, "%s suspicious label is: %s", pp->name, label);
193 		if (req != NULL)
194 			gctl_error(req, "Label name %s is invalid.", label);
195 		return (NULL);
196 	}
197 	gp = NULL;
198 	cp = NULL;
199 	snprintf(name, sizeof(name), "%s/%s", dir, label);
200 	LIST_FOREACH(gp, &mp->geom, geom) {
201 		pp2 = LIST_FIRST(&gp->provider);
202 		if (pp2 == NULL)
203 			continue;
204 		if ((pp2->flags & G_PF_ORPHAN) != 0)
205 			continue;
206 		if (strcmp(pp2->name, name) == 0) {
207 			G_LABEL_DEBUG(1, "Label %s(%s) already exists (%s).",
208 			    label, name, pp->name);
209 			if (req != NULL) {
210 				gctl_error(req, "Provider %s already exists.",
211 				    name);
212 			}
213 			return (NULL);
214 		}
215 	}
216 	gp = g_slice_new(mp, 1, pp, &cp, NULL, 0, NULL);
217 	if (gp == NULL) {
218 		G_LABEL_DEBUG(0, "Cannot create slice %s.", label);
219 		if (req != NULL)
220 			gctl_error(req, "Cannot create slice %s.", label);
221 		return (NULL);
222 	}
223 	gp->orphan = g_label_orphan;
224 	gp->spoiled = g_label_spoiled;
225 	gp->resize = g_label_resize;
226 	g_access(cp, -1, 0, 0);
227 	g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t)0, mediasize,
228 	    pp->sectorsize, "%s", name);
229 	G_LABEL_DEBUG(1, "Label for provider %s is %s.", pp->name, name);
230 	return (gp);
231 }
232 
233 static int
234 g_label_destroy(struct g_geom *gp, boolean_t force)
235 {
236 	struct g_provider *pp;
237 
238 	g_topology_assert();
239 	pp = LIST_FIRST(&gp->provider);
240 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
241 		if (force) {
242 			G_LABEL_DEBUG(0, "Provider %s is still open, so it "
243 			    "can't be definitely removed.", pp->name);
244 		} else {
245 			G_LABEL_DEBUG(1,
246 			    "Provider %s is still open (r%dw%de%d).", pp->name,
247 			    pp->acr, pp->acw, pp->ace);
248 			return (EBUSY);
249 		}
250 	} else if (pp != NULL)
251 		G_LABEL_DEBUG(1, "Label %s removed.", pp->name);
252 	g_slice_spoiled(LIST_FIRST(&gp->consumer));
253 	return (0);
254 }
255 
256 static int
257 g_label_read_metadata(struct g_consumer *cp, struct g_label_metadata *md)
258 {
259 	struct g_provider *pp;
260 	u_char *buf;
261 	int error;
262 
263 	g_topology_assert();
264 
265 	pp = cp->provider;
266 	g_topology_unlock();
267 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
268 	    &error);
269 	g_topology_lock();
270 	if (buf == NULL)
271 		return (error);
272 	/* Decode metadata. */
273 	label_metadata_decode(buf, md);
274 	g_free(buf);
275 
276 	return (0);
277 }
278 
279 static void
280 g_label_orphan_taste(struct g_consumer *cp __unused)
281 {
282 
283 	KASSERT(1 == 0, ("%s called?", __func__));
284 }
285 
286 static void
287 g_label_start_taste(struct bio *bp __unused)
288 {
289 
290 	KASSERT(1 == 0, ("%s called?", __func__));
291 }
292 
293 static int
294 g_label_access_taste(struct g_provider *pp __unused, int dr __unused,
295     int dw __unused, int de __unused)
296 {
297 
298 	KASSERT(1 == 0, ("%s called", __func__));
299 	return (EOPNOTSUPP);
300 }
301 
302 static struct g_geom *
303 g_label_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
304 {
305 	struct g_label_metadata md;
306 	struct g_consumer *cp;
307 	struct g_geom *gp;
308 	int i;
309 
310 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
311 	g_topology_assert();
312 
313 	G_LABEL_DEBUG(2, "Tasting %s.", pp->name);
314 
315 	/* Skip providers that are already open for writing. */
316 	if (pp->acw > 0)
317 		return (NULL);
318 
319 	if (strcmp(pp->geom->class->name, mp->name) == 0)
320 		return (NULL);
321 
322 	gp = g_new_geomf(mp, "label:taste");
323 	gp->start = g_label_start_taste;
324 	gp->access = g_label_access_taste;
325 	gp->orphan = g_label_orphan_taste;
326 	cp = g_new_consumer(gp);
327 	g_attach(cp, pp);
328 	if (g_access(cp, 1, 0, 0) != 0)
329 		goto end;
330 	do {
331 		if (g_label_read_metadata(cp, &md) != 0)
332 			break;
333 		if (strcmp(md.md_magic, G_LABEL_MAGIC) != 0)
334 			break;
335 		if (md.md_version > G_LABEL_VERSION) {
336 			printf("geom_label.ko module is too old to handle %s.\n",
337 			    pp->name);
338 			break;
339 		}
340 
341 		/*
342 		 * Backward compatibility:
343 		 */
344 		/*
345 		 * There was no md_provsize field in earlier versions of
346 		 * metadata.
347 		 */
348 		if (md.md_version < 2)
349 			md.md_provsize = pp->mediasize;
350 
351 		if (md.md_provsize != pp->mediasize)
352 			break;
353 
354 		g_label_create(NULL, mp, pp, md.md_label, G_LABEL_DIR,
355 		    pp->mediasize - pp->sectorsize);
356 	} while (0);
357 	for (i = 0; g_labels[i] != NULL; i++) {
358 		char label[128];
359 
360 		if (g_labels[i]->ld_enabled == 0)
361 			continue;
362 		g_topology_unlock();
363 		g_labels[i]->ld_taste(cp, label, sizeof(label));
364 		g_label_mangle_name(label, sizeof(label));
365 		g_topology_lock();
366 		if (label[0] == '\0')
367 			continue;
368 		g_label_create(NULL, mp, pp, label, g_labels[i]->ld_dir,
369 		    pp->mediasize);
370 	}
371 	g_access(cp, -1, 0, 0);
372 end:
373 	g_detach(cp);
374 	g_destroy_consumer(cp);
375 	g_destroy_geom(gp);
376 	return (NULL);
377 }
378 
379 static void
380 g_label_ctl_create(struct gctl_req *req, struct g_class *mp)
381 {
382 	struct g_provider *pp;
383 	const char *name;
384 	int *nargs;
385 
386 	g_topology_assert();
387 
388 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
389 	if (nargs == NULL) {
390 		gctl_error(req, "No '%s' argument", "nargs");
391 		return;
392 	}
393 	if (*nargs != 2) {
394 		gctl_error(req, "Invalid number of arguments.");
395 		return;
396 	}
397 	/*
398 	 * arg1 is the name of provider.
399 	 */
400 	name = gctl_get_asciiparam(req, "arg1");
401 	if (name == NULL) {
402 		gctl_error(req, "No 'arg%d' argument", 1);
403 		return;
404 	}
405 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
406 		name += strlen("/dev/");
407 	pp = g_provider_by_name(name);
408 	if (pp == NULL) {
409 		G_LABEL_DEBUG(1, "Provider %s is invalid.", name);
410 		gctl_error(req, "Provider %s is invalid.", name);
411 		return;
412 	}
413 	/*
414 	 * arg0 is the label.
415 	 */
416 	name = gctl_get_asciiparam(req, "arg0");
417 	if (name == NULL) {
418 		gctl_error(req, "No 'arg%d' argument", 0);
419 		return;
420 	}
421 	g_label_create(req, mp, pp, name, G_LABEL_DIR, pp->mediasize);
422 }
423 
424 static const char *
425 g_label_skip_dir(const char *name)
426 {
427 	char path[64];
428 	u_int i;
429 
430 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
431 		name += strlen("/dev/");
432 	if (strncmp(name, G_LABEL_DIR "/", strlen(G_LABEL_DIR "/")) == 0)
433 		name += strlen(G_LABEL_DIR "/");
434 	for (i = 0; g_labels[i] != NULL; i++) {
435 		snprintf(path, sizeof(path), "%s/", g_labels[i]->ld_dir);
436 		if (strncmp(name, path, strlen(path)) == 0) {
437 			name += strlen(path);
438 			break;
439 		}
440 	}
441 	return (name);
442 }
443 
444 static struct g_geom *
445 g_label_find_geom(struct g_class *mp, const char *name)
446 {
447 	struct g_geom *gp;
448 	struct g_provider *pp;
449 	const char *pname;
450 
451 	name = g_label_skip_dir(name);
452 	LIST_FOREACH(gp, &mp->geom, geom) {
453 		pp = LIST_FIRST(&gp->provider);
454 		pname = g_label_skip_dir(pp->name);
455 		if (strcmp(pname, name) == 0)
456 			return (gp);
457 	}
458 	return (NULL);
459 }
460 
461 static void
462 g_label_ctl_destroy(struct gctl_req *req, struct g_class *mp)
463 {
464 	int *nargs, *force, error, i;
465 	struct g_geom *gp;
466 	const char *name;
467 	char param[16];
468 
469 	g_topology_assert();
470 
471 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
472 	if (nargs == NULL) {
473 		gctl_error(req, "No '%s' argument", "nargs");
474 		return;
475 	}
476 	if (*nargs <= 0) {
477 		gctl_error(req, "Missing device(s).");
478 		return;
479 	}
480 	force = gctl_get_paraml(req, "force", sizeof(*force));
481 	if (force == NULL) {
482 		gctl_error(req, "No 'force' argument");
483 		return;
484 	}
485 
486 	for (i = 0; i < *nargs; i++) {
487 		snprintf(param, sizeof(param), "arg%d", i);
488 		name = gctl_get_asciiparam(req, param);
489 		if (name == NULL) {
490 			gctl_error(req, "No 'arg%d' argument", i);
491 			return;
492 		}
493 		gp = g_label_find_geom(mp, name);
494 		if (gp == NULL) {
495 			G_LABEL_DEBUG(1, "Label %s is invalid.", name);
496 			gctl_error(req, "Label %s is invalid.", name);
497 			return;
498 		}
499 		error = g_label_destroy(gp, *force);
500 		if (error != 0) {
501 			gctl_error(req, "Cannot destroy label %s (error=%d).",
502 			    LIST_FIRST(&gp->provider)->name, error);
503 			return;
504 		}
505 	}
506 }
507 
508 static void
509 g_label_config(struct gctl_req *req, struct g_class *mp, const char *verb)
510 {
511 	uint32_t *version;
512 
513 	g_topology_assert();
514 
515 	version = gctl_get_paraml(req, "version", sizeof(*version));
516 	if (version == NULL) {
517 		gctl_error(req, "No '%s' argument.", "version");
518 		return;
519 	}
520 	if (*version != G_LABEL_VERSION) {
521 		gctl_error(req, "Userland and kernel parts are out of sync.");
522 		return;
523 	}
524 
525 	if (strcmp(verb, "create") == 0) {
526 		g_label_ctl_create(req, mp);
527 		return;
528 	} else if (strcmp(verb, "destroy") == 0 ||
529 	    strcmp(verb, "stop") == 0) {
530 		g_label_ctl_destroy(req, mp);
531 		return;
532 	}
533 
534 	gctl_error(req, "Unknown verb.");
535 }
536 
537 DECLARE_GEOM_CLASS(g_label_class, g_label);
538