xref: /freebsd/sys/geom/label/g_label.c (revision 731d06abf2105cc0873fa84e972178f9f37ca760)
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_slice.h>
49 #include <geom/label/g_label.h>
50 
51 FEATURE(geom_label, "GEOM labeling support");
52 
53 SYSCTL_DECL(_kern_geom);
54 SYSCTL_NODE(_kern_geom, OID_AUTO, label, CTLFLAG_RW, 0, "GEOM_LABEL stuff");
55 u_int g_label_debug = 0;
56 SYSCTL_UINT(_kern_geom_label, OID_AUTO, debug, CTLFLAG_RWTUN, &g_label_debug, 0,
57     "Debug level");
58 
59 static int g_label_destroy_geom(struct gctl_req *req, struct g_class *mp,
60     struct g_geom *gp);
61 static int g_label_destroy(struct g_geom *gp, boolean_t force);
62 static struct g_geom *g_label_taste(struct g_class *mp, struct g_provider *pp,
63     int flags __unused);
64 static void g_label_config(struct gctl_req *req, struct g_class *mp,
65     const char *verb);
66 
67 struct g_class g_label_class = {
68 	.name = G_LABEL_CLASS_NAME,
69 	.version = G_VERSION,
70 	.ctlreq = g_label_config,
71 	.taste = g_label_taste,
72 	.destroy_geom = g_label_destroy_geom
73 };
74 
75 /*
76  * To add a new file system where you want to look for volume labels,
77  * you have to:
78  * 1. Add a file g_label_<file system>.c which implements labels recognition.
79  * 2. Add an 'extern const struct g_label_desc g_label_<file system>;' into
80  *    g_label.h file.
81  * 3. Add an element to the table below '&g_label_<file system>,'.
82  * 4. Add your file to sys/conf/files.
83  * 5. Add your file to sys/modules/geom/geom_label/Makefile.
84  * 6. Add your file system to manual page sbin/geom/class/label/glabel.8.
85  */
86 const struct g_label_desc *g_labels[] = {
87 	&g_label_gpt,
88 	&g_label_gpt_uuid,
89 #ifdef GEOM_LABEL
90 	&g_label_ufs_id,
91 	&g_label_ufs_volume,
92 	&g_label_iso9660,
93 	&g_label_msdosfs,
94 	&g_label_ext2fs,
95 	&g_label_reiserfs,
96 	&g_label_ntfs,
97 	&g_label_disk_ident,
98 	&g_label_flashmap,
99 #endif
100 	NULL
101 };
102 
103 void
104 g_label_rtrim(char *label, size_t size)
105 {
106 	ptrdiff_t i;
107 
108 	for (i = size - 1; i >= 0; i--) {
109 		if (label[i] == '\0')
110 			continue;
111 		else if (label[i] == ' ')
112 			label[i] = '\0';
113 		else
114 			break;
115 	}
116 }
117 
118 static int
119 g_label_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
120     struct g_geom *gp __unused)
121 {
122 
123 	/*
124 	 * XXX: Unloading a class which is using geom_slice:1.56 is currently
125 	 * XXX: broken, so we deny unloading when we have geoms.
126 	 */
127 	return (EOPNOTSUPP);
128 }
129 
130 static void
131 g_label_orphan(struct g_consumer *cp)
132 {
133 
134 	G_LABEL_DEBUG(1, "Label %s removed.",
135 	    LIST_FIRST(&cp->geom->provider)->name);
136 	g_slice_orphan(cp);
137 }
138 
139 static void
140 g_label_spoiled(struct g_consumer *cp)
141 {
142 
143 	G_LABEL_DEBUG(1, "Label %s removed.",
144 	    LIST_FIRST(&cp->geom->provider)->name);
145 	g_slice_spoiled(cp);
146 }
147 
148 static void
149 g_label_resize(struct g_consumer *cp)
150 {
151 
152 	G_LABEL_DEBUG(1, "Label %s resized.",
153 	    LIST_FIRST(&cp->geom->provider)->name);
154 
155 	g_slice_config(cp->geom, 0, G_SLICE_CONFIG_FORCE, (off_t)0,
156 	    cp->provider->mediasize, cp->provider->sectorsize, "notused");
157 }
158 
159 static int
160 g_label_is_name_ok(const char *label)
161 {
162 	const char *s;
163 
164 	/* Check if the label starts from ../ */
165 	if (strncmp(label, "../", 3) == 0)
166 		return (0);
167 	/* Check if the label contains /../ */
168 	if (strstr(label, "/../") != NULL)
169 		return (0);
170 	/* Check if the label ends at ../ */
171 	if ((s = strstr(label, "/..")) != NULL && s[3] == '\0')
172 		return (0);
173 	return (1);
174 }
175 
176 static void
177 g_label_mangle_name(char *label, size_t size)
178 {
179 	struct sbuf *sb;
180 	const u_char *c;
181 
182 	sb = sbuf_new(NULL, NULL, size, SBUF_FIXEDLEN);
183 	for (c = label; *c != '\0'; c++) {
184 		if (!isprint(*c) || isspace(*c) || *c =='"' || *c == '%')
185 			sbuf_printf(sb, "%%%02X", *c);
186 		else
187 			sbuf_putc(sb, *c);
188 	}
189 	if (sbuf_finish(sb) != 0)
190 		label[0] = '\0';
191 	else
192 		strlcpy(label, sbuf_data(sb), size);
193 	sbuf_delete(sb);
194 }
195 
196 static struct g_geom *
197 g_label_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
198     const char *label, const char *dir, off_t mediasize)
199 {
200 	struct g_geom *gp;
201 	struct g_provider *pp2;
202 	struct g_consumer *cp;
203 	char name[64];
204 
205 	g_topology_assert();
206 
207 	if (!g_label_is_name_ok(label)) {
208 		G_LABEL_DEBUG(0, "%s contains suspicious label, skipping.",
209 		    pp->name);
210 		G_LABEL_DEBUG(1, "%s suspicious label is: %s", pp->name, label);
211 		if (req != NULL)
212 			gctl_error(req, "Label name %s is invalid.", label);
213 		return (NULL);
214 	}
215 	gp = NULL;
216 	cp = NULL;
217 	if (snprintf(name, sizeof(name), "%s/%s", dir, label) >= sizeof(name)) {
218 		if (req != NULL)
219 			gctl_error(req, "Label name %s is too long.", label);
220 		return (NULL);
221 	}
222 	LIST_FOREACH(gp, &mp->geom, geom) {
223 		pp2 = LIST_FIRST(&gp->provider);
224 		if (pp2 == NULL)
225 			continue;
226 		if ((pp2->flags & G_PF_ORPHAN) != 0)
227 			continue;
228 		if (strcmp(pp2->name, name) == 0) {
229 			G_LABEL_DEBUG(1, "Label %s(%s) already exists (%s).",
230 			    label, name, pp->name);
231 			if (req != NULL) {
232 				gctl_error(req, "Provider %s already exists.",
233 				    name);
234 			}
235 			return (NULL);
236 		}
237 	}
238 	gp = g_slice_new(mp, 1, pp, &cp, NULL, 0, NULL);
239 	if (gp == NULL) {
240 		G_LABEL_DEBUG(0, "Cannot create slice %s.", label);
241 		if (req != NULL)
242 			gctl_error(req, "Cannot create slice %s.", label);
243 		return (NULL);
244 	}
245 	gp->orphan = g_label_orphan;
246 	gp->spoiled = g_label_spoiled;
247 	gp->resize = g_label_resize;
248 	g_access(cp, -1, 0, 0);
249 	g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t)0, mediasize,
250 	    pp->sectorsize, "%s", name);
251 	G_LABEL_DEBUG(1, "Label for provider %s is %s.", pp->name, name);
252 	return (gp);
253 }
254 
255 static int
256 g_label_destroy(struct g_geom *gp, boolean_t force)
257 {
258 	struct g_provider *pp;
259 
260 	g_topology_assert();
261 	pp = LIST_FIRST(&gp->provider);
262 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
263 		if (force) {
264 			G_LABEL_DEBUG(0, "Provider %s is still open, so it "
265 			    "can't be definitely removed.", pp->name);
266 		} else {
267 			G_LABEL_DEBUG(1,
268 			    "Provider %s is still open (r%dw%de%d).", pp->name,
269 			    pp->acr, pp->acw, pp->ace);
270 			return (EBUSY);
271 		}
272 	} else if (pp != NULL)
273 		G_LABEL_DEBUG(1, "Label %s removed.", pp->name);
274 	g_slice_spoiled(LIST_FIRST(&gp->consumer));
275 	return (0);
276 }
277 
278 static int
279 g_label_read_metadata(struct g_consumer *cp, struct g_label_metadata *md)
280 {
281 	struct g_provider *pp;
282 	u_char *buf;
283 	int error;
284 
285 	g_topology_assert();
286 
287 	pp = cp->provider;
288 	g_topology_unlock();
289 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
290 	    &error);
291 	g_topology_lock();
292 	if (buf == NULL)
293 		return (error);
294 	/* Decode metadata. */
295 	label_metadata_decode(buf, md);
296 	g_free(buf);
297 
298 	return (0);
299 }
300 
301 static void
302 g_label_orphan_taste(struct g_consumer *cp __unused)
303 {
304 
305 	KASSERT(1 == 0, ("%s called?", __func__));
306 }
307 
308 static void
309 g_label_start_taste(struct bio *bp __unused)
310 {
311 
312 	KASSERT(1 == 0, ("%s called?", __func__));
313 }
314 
315 static int
316 g_label_access_taste(struct g_provider *pp __unused, int dr __unused,
317     int dw __unused, int de __unused)
318 {
319 
320 	KASSERT(1 == 0, ("%s called", __func__));
321 	return (EOPNOTSUPP);
322 }
323 
324 static struct g_geom *
325 g_label_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
326 {
327 	struct g_label_metadata md;
328 	struct g_consumer *cp;
329 	struct g_geom *gp;
330 	int i;
331 
332 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
333 	g_topology_assert();
334 
335 	G_LABEL_DEBUG(2, "Tasting %s.", pp->name);
336 
337 	/* Skip providers that are already open for writing. */
338 	if (pp->acw > 0)
339 		return (NULL);
340 
341 	if (strcmp(pp->geom->class->name, mp->name) == 0)
342 		return (NULL);
343 
344 	gp = g_new_geomf(mp, "label:taste");
345 	gp->start = g_label_start_taste;
346 	gp->access = g_label_access_taste;
347 	gp->orphan = g_label_orphan_taste;
348 	cp = g_new_consumer(gp);
349 	g_attach(cp, pp);
350 	if (g_access(cp, 1, 0, 0) != 0)
351 		goto end;
352 	do {
353 		if (g_label_read_metadata(cp, &md) != 0)
354 			break;
355 		if (strcmp(md.md_magic, G_LABEL_MAGIC) != 0)
356 			break;
357 		if (md.md_version > G_LABEL_VERSION) {
358 			printf("geom_label.ko module is too old to handle %s.\n",
359 			    pp->name);
360 			break;
361 		}
362 
363 		/*
364 		 * Backward compatibility:
365 		 */
366 		/*
367 		 * There was no md_provsize field in earlier versions of
368 		 * metadata.
369 		 */
370 		if (md.md_version < 2)
371 			md.md_provsize = pp->mediasize;
372 
373 		if (md.md_provsize != pp->mediasize)
374 			break;
375 
376 		g_label_create(NULL, mp, pp, md.md_label, G_LABEL_DIR,
377 		    pp->mediasize - pp->sectorsize);
378 	} while (0);
379 	for (i = 0; g_labels[i] != NULL; i++) {
380 		char label[128];
381 
382 		if (g_labels[i]->ld_enabled == 0)
383 			continue;
384 		g_topology_unlock();
385 		g_labels[i]->ld_taste(cp, label, sizeof(label));
386 		g_label_mangle_name(label, sizeof(label));
387 		g_topology_lock();
388 		if (label[0] == '\0')
389 			continue;
390 		g_label_create(NULL, mp, pp, label, g_labels[i]->ld_dir,
391 		    pp->mediasize);
392 	}
393 	g_access(cp, -1, 0, 0);
394 end:
395 	g_detach(cp);
396 	g_destroy_consumer(cp);
397 	g_destroy_geom(gp);
398 	return (NULL);
399 }
400 
401 static void
402 g_label_ctl_create(struct gctl_req *req, struct g_class *mp)
403 {
404 	struct g_provider *pp;
405 	const char *name;
406 	int *nargs;
407 
408 	g_topology_assert();
409 
410 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
411 	if (nargs == NULL) {
412 		gctl_error(req, "No '%s' argument", "nargs");
413 		return;
414 	}
415 	if (*nargs != 2) {
416 		gctl_error(req, "Invalid number of arguments.");
417 		return;
418 	}
419 	/*
420 	 * arg1 is the name of provider.
421 	 */
422 	name = gctl_get_asciiparam(req, "arg1");
423 	if (name == NULL) {
424 		gctl_error(req, "No 'arg%d' argument", 1);
425 		return;
426 	}
427 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
428 		name += strlen("/dev/");
429 	pp = g_provider_by_name(name);
430 	if (pp == NULL) {
431 		G_LABEL_DEBUG(1, "Provider %s is invalid.", name);
432 		gctl_error(req, "Provider %s is invalid.", name);
433 		return;
434 	}
435 	/*
436 	 * arg0 is the label.
437 	 */
438 	name = gctl_get_asciiparam(req, "arg0");
439 	if (name == NULL) {
440 		gctl_error(req, "No 'arg%d' argument", 0);
441 		return;
442 	}
443 	g_label_create(req, mp, pp, name, G_LABEL_DIR, pp->mediasize);
444 }
445 
446 static const char *
447 g_label_skip_dir(const char *name)
448 {
449 	char path[64];
450 	u_int i;
451 
452 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
453 		name += strlen("/dev/");
454 	if (strncmp(name, G_LABEL_DIR "/", strlen(G_LABEL_DIR "/")) == 0)
455 		name += strlen(G_LABEL_DIR "/");
456 	for (i = 0; g_labels[i] != NULL; i++) {
457 		snprintf(path, sizeof(path), "%s/", g_labels[i]->ld_dir);
458 		if (strncmp(name, path, strlen(path)) == 0) {
459 			name += strlen(path);
460 			break;
461 		}
462 	}
463 	return (name);
464 }
465 
466 static struct g_geom *
467 g_label_find_geom(struct g_class *mp, const char *name)
468 {
469 	struct g_geom *gp;
470 	struct g_provider *pp;
471 	const char *pname;
472 
473 	name = g_label_skip_dir(name);
474 	LIST_FOREACH(gp, &mp->geom, geom) {
475 		pp = LIST_FIRST(&gp->provider);
476 		pname = g_label_skip_dir(pp->name);
477 		if (strcmp(pname, name) == 0)
478 			return (gp);
479 	}
480 	return (NULL);
481 }
482 
483 static void
484 g_label_ctl_destroy(struct gctl_req *req, struct g_class *mp)
485 {
486 	int *nargs, *force, error, i;
487 	struct g_geom *gp;
488 	const char *name;
489 	char param[16];
490 
491 	g_topology_assert();
492 
493 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
494 	if (nargs == NULL) {
495 		gctl_error(req, "No '%s' argument", "nargs");
496 		return;
497 	}
498 	if (*nargs <= 0) {
499 		gctl_error(req, "Missing device(s).");
500 		return;
501 	}
502 	force = gctl_get_paraml(req, "force", sizeof(*force));
503 	if (force == NULL) {
504 		gctl_error(req, "No 'force' argument");
505 		return;
506 	}
507 
508 	for (i = 0; i < *nargs; i++) {
509 		snprintf(param, sizeof(param), "arg%d", i);
510 		name = gctl_get_asciiparam(req, param);
511 		if (name == NULL) {
512 			gctl_error(req, "No 'arg%d' argument", i);
513 			return;
514 		}
515 		gp = g_label_find_geom(mp, name);
516 		if (gp == NULL) {
517 			G_LABEL_DEBUG(1, "Label %s is invalid.", name);
518 			gctl_error(req, "Label %s is invalid.", name);
519 			return;
520 		}
521 		error = g_label_destroy(gp, *force);
522 		if (error != 0) {
523 			gctl_error(req, "Cannot destroy label %s (error=%d).",
524 			    LIST_FIRST(&gp->provider)->name, error);
525 			return;
526 		}
527 	}
528 }
529 
530 static void
531 g_label_config(struct gctl_req *req, struct g_class *mp, const char *verb)
532 {
533 	uint32_t *version;
534 
535 	g_topology_assert();
536 
537 	version = gctl_get_paraml(req, "version", sizeof(*version));
538 	if (version == NULL) {
539 		gctl_error(req, "No '%s' argument.", "version");
540 		return;
541 	}
542 	if (*version != G_LABEL_VERSION) {
543 		gctl_error(req, "Userland and kernel parts are out of sync.");
544 		return;
545 	}
546 
547 	if (strcmp(verb, "create") == 0) {
548 		g_label_ctl_create(req, mp);
549 		return;
550 	} else if (strcmp(verb, "destroy") == 0 ||
551 	    strcmp(verb, "stop") == 0) {
552 		g_label_ctl_destroy(req, mp);
553 		return;
554 	}
555 
556 	gctl_error(req, "Unknown verb.");
557 }
558 
559 DECLARE_GEOM_CLASS(g_label_class, g_label);
560 MODULE_VERSION(geom_label, 0);
561