xref: /freebsd-11-stable/sys/geom/label/g_label.c (revision 9f437056f277c1dbad0b70c25c28ff500735e3a1)
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 	&g_label_flashmap,
97 #endif
98 	NULL
99 };
100 
101 void
g_label_rtrim(char * label,size_t size)102 g_label_rtrim(char *label, size_t size)
103 {
104 	ptrdiff_t i;
105 
106 	for (i = size - 1; i >= 0; i--) {
107 		if (label[i] == '\0')
108 			continue;
109 		else if (label[i] == ' ')
110 			label[i] = '\0';
111 		else
112 			break;
113 	}
114 }
115 
116 static int
g_label_destroy_geom(struct gctl_req * req __unused,struct g_class * mp,struct g_geom * gp __unused)117 g_label_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
118     struct g_geom *gp __unused)
119 {
120 
121 	/*
122 	 * XXX: Unloading a class which is using geom_slice:1.56 is currently
123 	 * XXX: broken, so we deny unloading when we have geoms.
124 	 */
125 	return (EOPNOTSUPP);
126 }
127 
128 static void
g_label_orphan(struct g_consumer * cp)129 g_label_orphan(struct g_consumer *cp)
130 {
131 
132 	G_LABEL_DEBUG(1, "Label %s removed.",
133 	    LIST_FIRST(&cp->geom->provider)->name);
134 	g_slice_orphan(cp);
135 }
136 
137 static void
g_label_spoiled(struct g_consumer * cp)138 g_label_spoiled(struct g_consumer *cp)
139 {
140 
141 	G_LABEL_DEBUG(1, "Label %s removed.",
142 	    LIST_FIRST(&cp->geom->provider)->name);
143 	g_slice_spoiled(cp);
144 }
145 
146 static void
g_label_resize(struct g_consumer * cp)147 g_label_resize(struct g_consumer *cp)
148 {
149 
150 	G_LABEL_DEBUG(1, "Label %s resized.",
151 	    LIST_FIRST(&cp->geom->provider)->name);
152 
153 	g_slice_config(cp->geom, 0, G_SLICE_CONFIG_FORCE, (off_t)0,
154 	    cp->provider->mediasize, cp->provider->sectorsize, "notused");
155 }
156 
157 static int
g_label_is_name_ok(const char * label)158 g_label_is_name_ok(const char *label)
159 {
160 	const char *s;
161 
162 	/* Check if the label starts from ../ */
163 	if (strncmp(label, "../", 3) == 0)
164 		return (0);
165 	/* Check if the label contains /../ */
166 	if (strstr(label, "/../") != NULL)
167 		return (0);
168 	/* Check if the label ends at ../ */
169 	if ((s = strstr(label, "/..")) != NULL && s[3] == '\0')
170 		return (0);
171 	return (1);
172 }
173 
174 static void
g_label_mangle_name(char * label,size_t size)175 g_label_mangle_name(char *label, size_t size)
176 {
177 	struct sbuf *sb;
178 	const u_char *c;
179 
180 	sb = sbuf_new(NULL, NULL, size, SBUF_FIXEDLEN);
181 	for (c = label; *c != '\0'; c++) {
182 		if (!isprint(*c) || isspace(*c) || *c =='"' || *c == '%')
183 			sbuf_printf(sb, "%%%02X", *c);
184 		else
185 			sbuf_putc(sb, *c);
186 	}
187 	if (sbuf_finish(sb) != 0)
188 		label[0] = '\0';
189 	else
190 		strlcpy(label, sbuf_data(sb), size);
191 	sbuf_delete(sb);
192 }
193 
194 static struct g_geom *
g_label_create(struct gctl_req * req,struct g_class * mp,struct g_provider * pp,const char * label,const char * dir,off_t mediasize)195 g_label_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
196     const char *label, const char *dir, off_t mediasize)
197 {
198 	struct g_geom *gp;
199 	struct g_provider *pp2;
200 	struct g_consumer *cp;
201 	char name[64];
202 
203 	g_topology_assert();
204 
205 	if (!g_label_is_name_ok(label)) {
206 		G_LABEL_DEBUG(0, "%s contains suspicious label, skipping.",
207 		    pp->name);
208 		G_LABEL_DEBUG(1, "%s suspicious label is: %s", pp->name, label);
209 		if (req != NULL)
210 			gctl_error(req, "Label name %s is invalid.", label);
211 		return (NULL);
212 	}
213 	gp = NULL;
214 	cp = NULL;
215 	snprintf(name, sizeof(name), "%s/%s", dir, label);
216 	LIST_FOREACH(gp, &mp->geom, geom) {
217 		pp2 = LIST_FIRST(&gp->provider);
218 		if (pp2 == NULL)
219 			continue;
220 		if ((pp2->flags & G_PF_ORPHAN) != 0)
221 			continue;
222 		if (strcmp(pp2->name, name) == 0) {
223 			G_LABEL_DEBUG(1, "Label %s(%s) already exists (%s).",
224 			    label, name, pp->name);
225 			if (req != NULL) {
226 				gctl_error(req, "Provider %s already exists.",
227 				    name);
228 			}
229 			return (NULL);
230 		}
231 	}
232 	gp = g_slice_new(mp, 1, pp, &cp, NULL, 0, NULL);
233 	if (gp == NULL) {
234 		G_LABEL_DEBUG(0, "Cannot create slice %s.", label);
235 		if (req != NULL)
236 			gctl_error(req, "Cannot create slice %s.", label);
237 		return (NULL);
238 	}
239 	gp->orphan = g_label_orphan;
240 	gp->spoiled = g_label_spoiled;
241 	gp->resize = g_label_resize;
242 	g_access(cp, -1, 0, 0);
243 	g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t)0, mediasize,
244 	    pp->sectorsize, "%s", name);
245 	G_LABEL_DEBUG(1, "Label for provider %s is %s.", pp->name, name);
246 	return (gp);
247 }
248 
249 static int
g_label_destroy(struct g_geom * gp,boolean_t force)250 g_label_destroy(struct g_geom *gp, boolean_t force)
251 {
252 	struct g_provider *pp;
253 
254 	g_topology_assert();
255 	pp = LIST_FIRST(&gp->provider);
256 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
257 		if (force) {
258 			G_LABEL_DEBUG(0, "Provider %s is still open, so it "
259 			    "can't be definitely removed.", pp->name);
260 		} else {
261 			G_LABEL_DEBUG(1,
262 			    "Provider %s is still open (r%dw%de%d).", pp->name,
263 			    pp->acr, pp->acw, pp->ace);
264 			return (EBUSY);
265 		}
266 	} else if (pp != NULL)
267 		G_LABEL_DEBUG(1, "Label %s removed.", pp->name);
268 	g_slice_spoiled(LIST_FIRST(&gp->consumer));
269 	return (0);
270 }
271 
272 static int
g_label_read_metadata(struct g_consumer * cp,struct g_label_metadata * md)273 g_label_read_metadata(struct g_consumer *cp, struct g_label_metadata *md)
274 {
275 	struct g_provider *pp;
276 	u_char *buf;
277 	int error;
278 
279 	g_topology_assert();
280 
281 	pp = cp->provider;
282 	g_topology_unlock();
283 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
284 	    &error);
285 	g_topology_lock();
286 	if (buf == NULL)
287 		return (error);
288 	/* Decode metadata. */
289 	label_metadata_decode(buf, md);
290 	g_free(buf);
291 
292 	return (0);
293 }
294 
295 static void
g_label_orphan_taste(struct g_consumer * cp __unused)296 g_label_orphan_taste(struct g_consumer *cp __unused)
297 {
298 
299 	KASSERT(1 == 0, ("%s called?", __func__));
300 }
301 
302 static void
g_label_start_taste(struct bio * bp __unused)303 g_label_start_taste(struct bio *bp __unused)
304 {
305 
306 	KASSERT(1 == 0, ("%s called?", __func__));
307 }
308 
309 static int
g_label_access_taste(struct g_provider * pp __unused,int dr __unused,int dw __unused,int de __unused)310 g_label_access_taste(struct g_provider *pp __unused, int dr __unused,
311     int dw __unused, int de __unused)
312 {
313 
314 	KASSERT(1 == 0, ("%s called", __func__));
315 	return (EOPNOTSUPP);
316 }
317 
318 static struct g_geom *
g_label_taste(struct g_class * mp,struct g_provider * pp,int flags __unused)319 g_label_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
320 {
321 	struct g_label_metadata md;
322 	struct g_consumer *cp;
323 	struct g_geom *gp;
324 	int i;
325 
326 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
327 	g_topology_assert();
328 
329 	G_LABEL_DEBUG(2, "Tasting %s.", pp->name);
330 
331 	/* Skip providers that are already open for writing. */
332 	if (pp->acw > 0)
333 		return (NULL);
334 
335 	if (strcmp(pp->geom->class->name, mp->name) == 0)
336 		return (NULL);
337 
338 	gp = g_new_geomf(mp, "label:taste");
339 	gp->start = g_label_start_taste;
340 	gp->access = g_label_access_taste;
341 	gp->orphan = g_label_orphan_taste;
342 	cp = g_new_consumer(gp);
343 	g_attach(cp, pp);
344 	if (g_access(cp, 1, 0, 0) != 0)
345 		goto end;
346 	do {
347 		if (g_label_read_metadata(cp, &md) != 0)
348 			break;
349 		if (strcmp(md.md_magic, G_LABEL_MAGIC) != 0)
350 			break;
351 		if (md.md_version > G_LABEL_VERSION) {
352 			printf("geom_label.ko module is too old to handle %s.\n",
353 			    pp->name);
354 			break;
355 		}
356 
357 		/*
358 		 * Backward compatibility:
359 		 */
360 		/*
361 		 * There was no md_provsize field in earlier versions of
362 		 * metadata.
363 		 */
364 		if (md.md_version < 2)
365 			md.md_provsize = pp->mediasize;
366 
367 		if (md.md_provsize != pp->mediasize)
368 			break;
369 
370 		g_label_create(NULL, mp, pp, md.md_label, G_LABEL_DIR,
371 		    pp->mediasize - pp->sectorsize);
372 	} while (0);
373 	for (i = 0; g_labels[i] != NULL; i++) {
374 		char label[128];
375 
376 		if (g_labels[i]->ld_enabled == 0)
377 			continue;
378 		g_topology_unlock();
379 		g_labels[i]->ld_taste(cp, label, sizeof(label));
380 		g_label_mangle_name(label, sizeof(label));
381 		g_topology_lock();
382 		if (label[0] == '\0')
383 			continue;
384 		g_label_create(NULL, mp, pp, label, g_labels[i]->ld_dir,
385 		    pp->mediasize);
386 	}
387 	g_access(cp, -1, 0, 0);
388 end:
389 	g_detach(cp);
390 	g_destroy_consumer(cp);
391 	g_destroy_geom(gp);
392 	return (NULL);
393 }
394 
395 static void
g_label_ctl_create(struct gctl_req * req,struct g_class * mp)396 g_label_ctl_create(struct gctl_req *req, struct g_class *mp)
397 {
398 	struct g_provider *pp;
399 	const char *name;
400 	int *nargs;
401 
402 	g_topology_assert();
403 
404 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
405 	if (nargs == NULL) {
406 		gctl_error(req, "No '%s' argument", "nargs");
407 		return;
408 	}
409 	if (*nargs != 2) {
410 		gctl_error(req, "Invalid number of arguments.");
411 		return;
412 	}
413 	/*
414 	 * arg1 is the name of provider.
415 	 */
416 	name = gctl_get_asciiparam(req, "arg1");
417 	if (name == NULL) {
418 		gctl_error(req, "No 'arg%d' argument", 1);
419 		return;
420 	}
421 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
422 		name += strlen("/dev/");
423 	pp = g_provider_by_name(name);
424 	if (pp == NULL) {
425 		G_LABEL_DEBUG(1, "Provider %s is invalid.", name);
426 		gctl_error(req, "Provider %s is invalid.", name);
427 		return;
428 	}
429 	/*
430 	 * arg0 is the label.
431 	 */
432 	name = gctl_get_asciiparam(req, "arg0");
433 	if (name == NULL) {
434 		gctl_error(req, "No 'arg%d' argument", 0);
435 		return;
436 	}
437 	g_label_create(req, mp, pp, name, G_LABEL_DIR, pp->mediasize);
438 }
439 
440 static const char *
g_label_skip_dir(const char * name)441 g_label_skip_dir(const char *name)
442 {
443 	char path[64];
444 	u_int i;
445 
446 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
447 		name += strlen("/dev/");
448 	if (strncmp(name, G_LABEL_DIR "/", strlen(G_LABEL_DIR "/")) == 0)
449 		name += strlen(G_LABEL_DIR "/");
450 	for (i = 0; g_labels[i] != NULL; i++) {
451 		snprintf(path, sizeof(path), "%s/", g_labels[i]->ld_dir);
452 		if (strncmp(name, path, strlen(path)) == 0) {
453 			name += strlen(path);
454 			break;
455 		}
456 	}
457 	return (name);
458 }
459 
460 static struct g_geom *
g_label_find_geom(struct g_class * mp,const char * name)461 g_label_find_geom(struct g_class *mp, const char *name)
462 {
463 	struct g_geom *gp;
464 	struct g_provider *pp;
465 	const char *pname;
466 
467 	name = g_label_skip_dir(name);
468 	LIST_FOREACH(gp, &mp->geom, geom) {
469 		pp = LIST_FIRST(&gp->provider);
470 		pname = g_label_skip_dir(pp->name);
471 		if (strcmp(pname, name) == 0)
472 			return (gp);
473 	}
474 	return (NULL);
475 }
476 
477 static void
g_label_ctl_destroy(struct gctl_req * req,struct g_class * mp)478 g_label_ctl_destroy(struct gctl_req *req, struct g_class *mp)
479 {
480 	int *nargs, *force, error, i;
481 	struct g_geom *gp;
482 	const char *name;
483 	char param[16];
484 
485 	g_topology_assert();
486 
487 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
488 	if (nargs == NULL) {
489 		gctl_error(req, "No '%s' argument", "nargs");
490 		return;
491 	}
492 	if (*nargs <= 0) {
493 		gctl_error(req, "Missing device(s).");
494 		return;
495 	}
496 	force = gctl_get_paraml(req, "force", sizeof(*force));
497 	if (force == NULL) {
498 		gctl_error(req, "No 'force' argument");
499 		return;
500 	}
501 
502 	for (i = 0; i < *nargs; i++) {
503 		snprintf(param, sizeof(param), "arg%d", i);
504 		name = gctl_get_asciiparam(req, param);
505 		if (name == NULL) {
506 			gctl_error(req, "No 'arg%d' argument", i);
507 			return;
508 		}
509 		gp = g_label_find_geom(mp, name);
510 		if (gp == NULL) {
511 			G_LABEL_DEBUG(1, "Label %s is invalid.", name);
512 			gctl_error(req, "Label %s is invalid.", name);
513 			return;
514 		}
515 		error = g_label_destroy(gp, *force);
516 		if (error != 0) {
517 			gctl_error(req, "Cannot destroy label %s (error=%d).",
518 			    LIST_FIRST(&gp->provider)->name, error);
519 			return;
520 		}
521 	}
522 }
523 
524 static void
g_label_config(struct gctl_req * req,struct g_class * mp,const char * verb)525 g_label_config(struct gctl_req *req, struct g_class *mp, const char *verb)
526 {
527 	uint32_t *version;
528 
529 	g_topology_assert();
530 
531 	version = gctl_get_paraml(req, "version", sizeof(*version));
532 	if (version == NULL) {
533 		gctl_error(req, "No '%s' argument.", "version");
534 		return;
535 	}
536 	if (*version != G_LABEL_VERSION) {
537 		gctl_error(req, "Userland and kernel parts are out of sync.");
538 		return;
539 	}
540 
541 	if (strcmp(verb, "create") == 0) {
542 		g_label_ctl_create(req, mp);
543 		return;
544 	} else if (strcmp(verb, "destroy") == 0 ||
545 	    strcmp(verb, "stop") == 0) {
546 		g_label_ctl_destroy(req, mp);
547 		return;
548 	}
549 
550 	gctl_error(req, "Unknown verb.");
551 }
552 
553 DECLARE_GEOM_CLASS(g_label_class, g_label);
554 MODULE_VERSION(geom_label, 0);
555