xref: /freebsd/sys/geom/label/g_label.c (revision 0bf56da32d83fbd3b5db8d6c72cd1e7cc26fbc66)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2004-2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_geom.h"
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/module.h>
38 #include <sys/lock.h>
39 #include <sys/mutex.h>
40 #include <sys/bio.h>
41 #include <sys/ctype.h>
42 #include <sys/malloc.h>
43 #include <sys/libkern.h>
44 #include <sys/sbuf.h>
45 #include <sys/stddef.h>
46 #include <sys/sysctl.h>
47 #include <geom/geom.h>
48 #include <geom/geom_dbg.h>
49 #include <geom/geom_slice.h>
50 #include <geom/label/g_label.h>
51 
52 FEATURE(geom_label, "GEOM labeling support");
53 
54 SYSCTL_DECL(_kern_geom);
55 SYSCTL_NODE(_kern_geom, OID_AUTO, label, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
56     "GEOM_LABEL stuff");
57 u_int g_label_debug = 0;
58 SYSCTL_UINT(_kern_geom_label, OID_AUTO, debug, CTLFLAG_RWTUN, &g_label_debug, 0,
59     "Debug level");
60 
61 static int g_label_destroy_geom(struct gctl_req *req, struct g_class *mp,
62     struct g_geom *gp);
63 static int g_label_destroy(struct g_geom *gp, boolean_t force);
64 static struct g_geom *g_label_taste(struct g_class *mp, struct g_provider *pp,
65     int flags __unused);
66 static void g_label_config(struct gctl_req *req, struct g_class *mp,
67     const char *verb);
68 
69 struct g_class g_label_class = {
70 	.name = G_LABEL_CLASS_NAME,
71 	.version = G_VERSION,
72 	.ctlreq = g_label_config,
73 	.taste = g_label_taste,
74 	.destroy_geom = g_label_destroy_geom
75 };
76 
77 /*
78  * To add a new file system where you want to look for volume labels,
79  * you have to:
80  * 1. Add a file g_label_<file system>.c which implements labels recognition.
81  * 2. Add an 'extern const struct g_label_desc g_label_<file system>;' into
82  *    g_label.h file.
83  * 3. Add an element to the table below '&g_label_<file system>,'.
84  * 4. Add your file to sys/conf/files.
85  * 5. Add your file to sys/modules/geom/geom_label/Makefile.
86  * 6. Add your file system to manual page sbin/geom/class/label/glabel.8.
87  */
88 const struct g_label_desc *g_labels[] = {
89 	&g_label_gpt,
90 	&g_label_gpt_uuid,
91 #ifdef GEOM_LABEL
92 	&g_label_ufs_id,
93 	&g_label_ufs_volume,
94 	&g_label_iso9660,
95 	&g_label_msdosfs,
96 	&g_label_ext2fs,
97 	&g_label_reiserfs,
98 	&g_label_ntfs,
99 	&g_label_disk_ident,
100 	&g_label_flashmap,
101 #endif
102 	NULL
103 };
104 
105 void
106 g_label_rtrim(char *label, size_t size)
107 {
108 	ptrdiff_t i;
109 
110 	for (i = size - 1; i >= 0; i--) {
111 		if (label[i] == '\0')
112 			continue;
113 		else if (label[i] == ' ')
114 			label[i] = '\0';
115 		else
116 			break;
117 	}
118 }
119 
120 static int
121 g_label_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
122     struct g_geom *gp __unused)
123 {
124 
125 	/*
126 	 * XXX: Unloading a class which is using geom_slice:1.56 is currently
127 	 * XXX: broken, so we deny unloading when we have geoms.
128 	 */
129 	return (EOPNOTSUPP);
130 }
131 
132 static void
133 g_label_orphan(struct g_consumer *cp)
134 {
135 
136 	G_LABEL_DEBUG(1, "Label %s removed.",
137 	    LIST_FIRST(&cp->geom->provider)->name);
138 	g_slice_orphan(cp);
139 }
140 
141 static void
142 g_label_spoiled(struct g_consumer *cp)
143 {
144 
145 	G_LABEL_DEBUG(1, "Label %s removed.",
146 	    LIST_FIRST(&cp->geom->provider)->name);
147 	g_slice_spoiled(cp);
148 }
149 
150 static void
151 g_label_resize(struct g_consumer *cp)
152 {
153 
154 	G_LABEL_DEBUG(1, "Label %s resized.",
155 	    LIST_FIRST(&cp->geom->provider)->name);
156 
157 	g_slice_config(cp->geom, 0, G_SLICE_CONFIG_FORCE, (off_t)0,
158 	    cp->provider->mediasize, cp->provider->sectorsize, "notused");
159 }
160 
161 static int
162 g_label_is_name_ok(const char *label)
163 {
164 	const char *s;
165 
166 	/* Check if the label starts from ../ */
167 	if (strncmp(label, "../", 3) == 0)
168 		return (0);
169 	/* Check if the label contains /../ */
170 	if (strstr(label, "/../") != NULL)
171 		return (0);
172 	/* Check if the label ends at ../ */
173 	if ((s = strstr(label, "/..")) != NULL && s[3] == '\0')
174 		return (0);
175 	return (1);
176 }
177 
178 static void
179 g_label_mangle_name(char *label, size_t size)
180 {
181 	struct sbuf *sb;
182 	const u_char *c;
183 	size_t len, i;
184 
185 	/* Trim trailing whitespace. */
186 	len = strlen(label);
187 	for (i = len; i > 0; i--) {
188 		if (isspace(label[i - 1]))
189 			label[i - 1] = '\0';
190 		else
191 			break;
192 	}
193 	if (*label == '\0')
194 		return;
195 
196 
197 	sb = sbuf_new(NULL, NULL, size, SBUF_FIXEDLEN);
198 	for (c = label; *c != '\0'; c++) {
199 		/* Trim leading whitespace. */
200 		if (isspace(*c) && sbuf_len(sb) == 0)
201 			continue;
202 		if (!isprint(*c) || isspace(*c) || *c =='"' || *c == '%')
203 			sbuf_printf(sb, "%%%02X", *c);
204 		else
205 			sbuf_putc(sb, *c);
206 	}
207 	if (sbuf_finish(sb) != 0)
208 		label[0] = '\0';
209 	else
210 		strlcpy(label, sbuf_data(sb), size);
211 	sbuf_delete(sb);
212 }
213 
214 static struct g_geom *
215 g_label_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
216     const char *label, const char *dir, off_t mediasize)
217 {
218 	struct g_geom *gp;
219 	struct g_provider *pp2;
220 	struct g_consumer *cp;
221 	char name[64];
222 
223 	g_topology_assert();
224 
225 	if (!g_label_is_name_ok(label)) {
226 		G_LABEL_DEBUG(0, "%s contains suspicious label, skipping.",
227 		    pp->name);
228 		G_LABEL_DEBUG(1, "%s suspicious label is: %s", pp->name, label);
229 		if (req != NULL)
230 			gctl_error(req, "Label name %s is invalid.", label);
231 		return (NULL);
232 	}
233 	gp = NULL;
234 	cp = NULL;
235 	if (snprintf(name, sizeof(name), "%s/%s", dir, label) >= sizeof(name)) {
236 		if (req != NULL)
237 			gctl_error(req, "Label name %s is too long.", label);
238 		return (NULL);
239 	}
240 	LIST_FOREACH(gp, &mp->geom, geom) {
241 		pp2 = LIST_FIRST(&gp->provider);
242 		if (pp2 == NULL)
243 			continue;
244 		if ((pp2->flags & G_PF_ORPHAN) != 0)
245 			continue;
246 		if (strcmp(pp2->name, name) == 0) {
247 			G_LABEL_DEBUG(1, "Label %s(%s) already exists (%s).",
248 			    label, name, pp->name);
249 			if (req != NULL) {
250 				gctl_error(req, "Provider %s already exists.",
251 				    name);
252 			}
253 			return (NULL);
254 		}
255 	}
256 	gp = g_slice_new(mp, 1, pp, &cp, NULL, 0, NULL);
257 	if (gp == NULL) {
258 		G_LABEL_DEBUG(0, "Cannot create slice %s.", label);
259 		if (req != NULL)
260 			gctl_error(req, "Cannot create slice %s.", label);
261 		return (NULL);
262 	}
263 	gp->orphan = g_label_orphan;
264 	gp->spoiled = g_label_spoiled;
265 	gp->resize = g_label_resize;
266 	g_access(cp, -1, 0, 0);
267 	g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t)0, mediasize,
268 	    pp->sectorsize, "%s", name);
269 	G_LABEL_DEBUG(1, "Label for provider %s is %s.", pp->name, name);
270 	return (gp);
271 }
272 
273 static int
274 g_label_destroy(struct g_geom *gp, boolean_t force)
275 {
276 	struct g_provider *pp;
277 
278 	g_topology_assert();
279 	pp = LIST_FIRST(&gp->provider);
280 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
281 		if (force) {
282 			G_LABEL_DEBUG(0, "Provider %s is still open, so it "
283 			    "can't be definitely removed.", pp->name);
284 		} else {
285 			G_LABEL_DEBUG(1,
286 			    "Provider %s is still open (r%dw%de%d).", pp->name,
287 			    pp->acr, pp->acw, pp->ace);
288 			return (EBUSY);
289 		}
290 	} else if (pp != NULL)
291 		G_LABEL_DEBUG(1, "Label %s removed.", pp->name);
292 	g_slice_spoiled(LIST_FIRST(&gp->consumer));
293 	return (0);
294 }
295 
296 static int
297 g_label_read_metadata(struct g_consumer *cp, struct g_label_metadata *md)
298 {
299 	struct g_provider *pp;
300 	u_char *buf;
301 	int error;
302 
303 	g_topology_assert();
304 
305 	pp = cp->provider;
306 	g_topology_unlock();
307 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
308 	    &error);
309 	g_topology_lock();
310 	if (buf == NULL)
311 		return (error);
312 	/* Decode metadata. */
313 	label_metadata_decode(buf, md);
314 	g_free(buf);
315 
316 	return (0);
317 }
318 
319 static void
320 g_label_orphan_taste(struct g_consumer *cp __unused)
321 {
322 
323 	KASSERT(1 == 0, ("%s called?", __func__));
324 }
325 
326 static void
327 g_label_start_taste(struct bio *bp __unused)
328 {
329 
330 	KASSERT(1 == 0, ("%s called?", __func__));
331 }
332 
333 static int
334 g_label_access_taste(struct g_provider *pp __unused, int dr __unused,
335     int dw __unused, int de __unused)
336 {
337 
338 	KASSERT(1 == 0, ("%s called", __func__));
339 	return (EOPNOTSUPP);
340 }
341 
342 static struct g_geom *
343 g_label_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
344 {
345 	struct g_label_metadata md;
346 	struct g_consumer *cp;
347 	struct g_geom *gp;
348 	int i;
349 
350 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
351 	g_topology_assert();
352 
353 	G_LABEL_DEBUG(2, "Tasting %s.", pp->name);
354 
355 	/* Skip providers that are already open for writing. */
356 	if (pp->acw > 0)
357 		return (NULL);
358 
359 	if (strcmp(pp->geom->class->name, mp->name) == 0)
360 		return (NULL);
361 
362 	gp = g_new_geomf(mp, "label:taste");
363 	gp->start = g_label_start_taste;
364 	gp->access = g_label_access_taste;
365 	gp->orphan = g_label_orphan_taste;
366 	cp = g_new_consumer(gp);
367 	g_attach(cp, pp);
368 	if (g_access(cp, 1, 0, 0) != 0)
369 		goto end;
370 	do {
371 		if (g_label_read_metadata(cp, &md) != 0)
372 			break;
373 		if (strcmp(md.md_magic, G_LABEL_MAGIC) != 0)
374 			break;
375 		if (md.md_version > G_LABEL_VERSION) {
376 			printf("geom_label.ko module is too old to handle %s.\n",
377 			    pp->name);
378 			break;
379 		}
380 
381 		/*
382 		 * Backward compatibility:
383 		 */
384 		/*
385 		 * There was no md_provsize field in earlier versions of
386 		 * metadata.
387 		 */
388 		if (md.md_version < 2)
389 			md.md_provsize = pp->mediasize;
390 
391 		if (md.md_provsize != pp->mediasize)
392 			break;
393 
394 		g_label_create(NULL, mp, pp, md.md_label, G_LABEL_DIR,
395 		    pp->mediasize - pp->sectorsize);
396 	} while (0);
397 	for (i = 0; g_labels[i] != NULL; i++) {
398 		char label[128];
399 
400 		if (g_labels[i]->ld_enabled == 0)
401 			continue;
402 		g_topology_unlock();
403 		g_labels[i]->ld_taste(cp, label, sizeof(label));
404 		g_label_mangle_name(label, sizeof(label));
405 		g_topology_lock();
406 		if (label[0] == '\0')
407 			continue;
408 		g_label_create(NULL, mp, pp, label, g_labels[i]->ld_dir,
409 		    pp->mediasize);
410 	}
411 	g_access(cp, -1, 0, 0);
412 end:
413 	g_detach(cp);
414 	g_destroy_consumer(cp);
415 	g_destroy_geom(gp);
416 	return (NULL);
417 }
418 
419 static void
420 g_label_ctl_create(struct gctl_req *req, struct g_class *mp)
421 {
422 	struct g_provider *pp;
423 	const char *name;
424 	int *nargs;
425 
426 	g_topology_assert();
427 
428 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
429 	if (nargs == NULL) {
430 		gctl_error(req, "No '%s' argument", "nargs");
431 		return;
432 	}
433 	if (*nargs != 2) {
434 		gctl_error(req, "Invalid number of arguments.");
435 		return;
436 	}
437 	/*
438 	 * arg1 is the name of provider.
439 	 */
440 	name = gctl_get_asciiparam(req, "arg1");
441 	if (name == NULL) {
442 		gctl_error(req, "No 'arg%d' argument", 1);
443 		return;
444 	}
445 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
446 		name += strlen("/dev/");
447 	pp = g_provider_by_name(name);
448 	if (pp == NULL) {
449 		G_LABEL_DEBUG(1, "Provider %s is invalid.", name);
450 		gctl_error(req, "Provider %s is invalid.", name);
451 		return;
452 	}
453 	/*
454 	 * arg0 is the label.
455 	 */
456 	name = gctl_get_asciiparam(req, "arg0");
457 	if (name == NULL) {
458 		gctl_error(req, "No 'arg%d' argument", 0);
459 		return;
460 	}
461 	g_label_create(req, mp, pp, name, G_LABEL_DIR, pp->mediasize);
462 }
463 
464 static const char *
465 g_label_skip_dir(const char *name)
466 {
467 	char path[64];
468 	u_int i;
469 
470 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
471 		name += strlen("/dev/");
472 	if (strncmp(name, G_LABEL_DIR "/", strlen(G_LABEL_DIR "/")) == 0)
473 		name += strlen(G_LABEL_DIR "/");
474 	for (i = 0; g_labels[i] != NULL; i++) {
475 		snprintf(path, sizeof(path), "%s/", g_labels[i]->ld_dir);
476 		if (strncmp(name, path, strlen(path)) == 0) {
477 			name += strlen(path);
478 			break;
479 		}
480 	}
481 	return (name);
482 }
483 
484 static struct g_geom *
485 g_label_find_geom(struct g_class *mp, const char *name)
486 {
487 	struct g_geom *gp;
488 	struct g_provider *pp;
489 	const char *pname;
490 
491 	name = g_label_skip_dir(name);
492 	LIST_FOREACH(gp, &mp->geom, geom) {
493 		pp = LIST_FIRST(&gp->provider);
494 		pname = g_label_skip_dir(pp->name);
495 		if (strcmp(pname, name) == 0)
496 			return (gp);
497 	}
498 	return (NULL);
499 }
500 
501 static void
502 g_label_ctl_destroy(struct gctl_req *req, struct g_class *mp)
503 {
504 	int *nargs, *force, error, i;
505 	struct g_geom *gp;
506 	const char *name;
507 	char param[16];
508 
509 	g_topology_assert();
510 
511 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
512 	if (nargs == NULL) {
513 		gctl_error(req, "No '%s' argument", "nargs");
514 		return;
515 	}
516 	if (*nargs <= 0) {
517 		gctl_error(req, "Missing device(s).");
518 		return;
519 	}
520 	force = gctl_get_paraml(req, "force", sizeof(*force));
521 	if (force == NULL) {
522 		gctl_error(req, "No 'force' argument");
523 		return;
524 	}
525 
526 	for (i = 0; i < *nargs; i++) {
527 		snprintf(param, sizeof(param), "arg%d", i);
528 		name = gctl_get_asciiparam(req, param);
529 		if (name == NULL) {
530 			gctl_error(req, "No 'arg%d' argument", i);
531 			return;
532 		}
533 		gp = g_label_find_geom(mp, name);
534 		if (gp == NULL) {
535 			G_LABEL_DEBUG(1, "Label %s is invalid.", name);
536 			gctl_error(req, "Label %s is invalid.", name);
537 			return;
538 		}
539 		error = g_label_destroy(gp, *force);
540 		if (error != 0) {
541 			gctl_error(req, "Cannot destroy label %s (error=%d).",
542 			    LIST_FIRST(&gp->provider)->name, error);
543 			return;
544 		}
545 	}
546 }
547 
548 static void
549 g_label_config(struct gctl_req *req, struct g_class *mp, const char *verb)
550 {
551 	uint32_t *version;
552 
553 	g_topology_assert();
554 
555 	version = gctl_get_paraml(req, "version", sizeof(*version));
556 	if (version == NULL) {
557 		gctl_error(req, "No '%s' argument.", "version");
558 		return;
559 	}
560 	if (*version != G_LABEL_VERSION) {
561 		gctl_error(req, "Userland and kernel parts are out of sync.");
562 		return;
563 	}
564 
565 	if (strcmp(verb, "create") == 0) {
566 		g_label_ctl_create(req, mp);
567 		return;
568 	} else if (strcmp(verb, "destroy") == 0 ||
569 	    strcmp(verb, "stop") == 0) {
570 		g_label_ctl_destroy(req, mp);
571 		return;
572 	}
573 
574 	gctl_error(req, "Unknown verb.");
575 }
576 
577 DECLARE_GEOM_CLASS(g_label_class, g_label);
578 MODULE_VERSION(geom_label, 0);
579