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 <sys/param.h>
31#include <sys/systm.h>
32#include <sys/kernel.h>
33#include <sys/module.h>
34#include <sys/lock.h>
35#include <sys/mutex.h>
36#include <sys/bio.h>
37#include <sys/ctype.h>
38#include <sys/malloc.h>
39#include <sys/libkern.h>
40#include <sys/sbuf.h>
41#include <sys/stddef.h>
42#include <sys/sysctl.h>
43#include <geom/geom.h>
44#include <geom/geom_slice.h>
45#include <geom/label/g_label.h>
46
47FEATURE(geom_label, "GEOM labeling support");
48
49SYSCTL_DECL(_kern_geom);
50SYSCTL_NODE(_kern_geom, OID_AUTO, label, CTLFLAG_RW, 0, "GEOM_LABEL stuff");
51u_int g_label_debug = 0;
52TUNABLE_INT("kern.geom.label.debug", &g_label_debug);
53SYSCTL_UINT(_kern_geom_label, OID_AUTO, debug, CTLFLAG_RW, &g_label_debug, 0,
54    "Debug level");
55
56static int g_label_destroy_geom(struct gctl_req *req, struct g_class *mp,
57    struct g_geom *gp);
58static int g_label_destroy(struct g_geom *gp, boolean_t force);
59static struct g_geom *g_label_taste(struct g_class *mp, struct g_provider *pp,
60    int flags __unused);
61static void g_label_config(struct gctl_req *req, struct g_class *mp,
62    const char *verb);
63
64struct 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 */
83const struct g_label_desc *g_labels[] = {
84	&g_label_ufs_id,
85	&g_label_ufs_volume,
86	&g_label_iso9660,
87	&g_label_msdosfs,
88	&g_label_ext2fs,
89	&g_label_reiserfs,
90	&g_label_ntfs,
91	&g_label_gpt,
92	&g_label_gpt_uuid,
93	&g_label_disk_ident,
94	NULL
95};
96
97void
98g_label_rtrim(char *label, size_t size)
99{
100	ptrdiff_t i;
101
102	for (i = size - 1; i >= 0; i--) {
103		if (label[i] == '\0')
104			continue;
105		else if (label[i] == ' ')
106			label[i] = '\0';
107		else
108			break;
109	}
110}
111
112static int
113g_label_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
114    struct g_geom *gp __unused)
115{
116
117	/*
118	 * XXX: Unloading a class which is using geom_slice:1.56 is currently
119	 * XXX: broken, so we deny unloading when we have geoms.
120	 */
121	return (EOPNOTSUPP);
122}
123
124static void
125g_label_orphan(struct g_consumer *cp)
126{
127
128	G_LABEL_DEBUG(1, "Label %s removed.",
129	    LIST_FIRST(&cp->geom->provider)->name);
130	g_slice_orphan(cp);
131}
132
133static void
134g_label_spoiled(struct g_consumer *cp)
135{
136
137	G_LABEL_DEBUG(1, "Label %s removed.",
138	    LIST_FIRST(&cp->geom->provider)->name);
139	g_slice_spoiled(cp);
140}
141
142static void
143g_label_resize(struct g_consumer *cp)
144{
145
146	G_LABEL_DEBUG(1, "Label %s resized.",
147	    LIST_FIRST(&cp->geom->provider)->name);
148
149	g_slice_config(cp->geom, 0, G_SLICE_CONFIG_FORCE, (off_t)0,
150	    cp->provider->mediasize, cp->provider->sectorsize, "notused");
151}
152
153static int
154g_label_is_name_ok(const char *label)
155{
156	const char *s;
157
158	/* Check if the label starts from ../ */
159	if (strncmp(label, "../", 3) == 0)
160		return (0);
161	/* Check if the label contains /../ */
162	if (strstr(label, "/../") != NULL)
163		return (0);
164	/* Check if the label ends at ../ */
165	if ((s = strstr(label, "/..")) != NULL && s[3] == '\0')
166		return (0);
167	return (1);
168}
169
170static void
171g_label_mangle_name(char *label, size_t size)
172{
173	struct sbuf *sb;
174	const u_char *c;
175
176	sb = sbuf_new(NULL, NULL, size, SBUF_FIXEDLEN);
177	for (c = label; *c != '\0'; c++) {
178		if (!isprint(*c) || isspace(*c) || *c =='"' || *c == '%')
179			sbuf_printf(sb, "%%%02X", *c);
180		else
181			sbuf_putc(sb, *c);
182	}
183	if (sbuf_finish(sb) != 0)
184		label[0] = '\0';
185	else
186		strlcpy(label, sbuf_data(sb), size);
187	sbuf_delete(sb);
188}
189
190static struct g_geom *
191g_label_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
192    const char *label, const char *dir, off_t mediasize)
193{
194	struct g_geom *gp;
195	struct g_provider *pp2;
196	struct g_consumer *cp;
197	char name[64];
198
199	g_topology_assert();
200
201	if (!g_label_is_name_ok(label)) {
202		G_LABEL_DEBUG(0, "%s contains suspicious label, skipping.",
203		    pp->name);
204		G_LABEL_DEBUG(1, "%s suspicious label is: %s", pp->name, label);
205		if (req != NULL)
206			gctl_error(req, "Label name %s is invalid.", label);
207		return (NULL);
208	}
209	gp = NULL;
210	cp = NULL;
211	snprintf(name, sizeof(name), "%s/%s", dir, label);
212	LIST_FOREACH(gp, &mp->geom, geom) {
213		pp2 = LIST_FIRST(&gp->provider);
214		if (pp2 == NULL)
215			continue;
216		if ((pp2->flags & G_PF_ORPHAN) != 0)
217			continue;
218		if (strcmp(pp2->name, name) == 0) {
219			G_LABEL_DEBUG(1, "Label %s(%s) already exists (%s).",
220			    label, name, pp->name);
221			if (req != NULL) {
222				gctl_error(req, "Provider %s already exists.",
223				    name);
224			}
225			return (NULL);
226		}
227	}
228	gp = g_slice_new(mp, 1, pp, &cp, NULL, 0, NULL);
229	if (gp == NULL) {
230		G_LABEL_DEBUG(0, "Cannot create slice %s.", label);
231		if (req != NULL)
232			gctl_error(req, "Cannot create slice %s.", label);
233		return (NULL);
234	}
235	gp->orphan = g_label_orphan;
236	gp->spoiled = g_label_spoiled;
237	gp->resize = g_label_resize;
238	g_access(cp, -1, 0, 0);
239	g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t)0, mediasize,
240	    pp->sectorsize, "%s", name);
241	G_LABEL_DEBUG(1, "Label for provider %s is %s.", pp->name, name);
242	return (gp);
243}
244
245static int
246g_label_destroy(struct g_geom *gp, boolean_t force)
247{
248	struct g_provider *pp;
249
250	g_topology_assert();
251	pp = LIST_FIRST(&gp->provider);
252	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
253		if (force) {
254			G_LABEL_DEBUG(0, "Provider %s is still open, so it "
255			    "can't be definitely removed.", pp->name);
256		} else {
257			G_LABEL_DEBUG(1,
258			    "Provider %s is still open (r%dw%de%d).", pp->name,
259			    pp->acr, pp->acw, pp->ace);
260			return (EBUSY);
261		}
262	} else if (pp != NULL)
263		G_LABEL_DEBUG(1, "Label %s removed.", pp->name);
264	g_slice_spoiled(LIST_FIRST(&gp->consumer));
265	return (0);
266}
267
268static int
269g_label_read_metadata(struct g_consumer *cp, struct g_label_metadata *md)
270{
271	struct g_provider *pp;
272	u_char *buf;
273	int error;
274
275	g_topology_assert();
276
277	pp = cp->provider;
278	g_topology_unlock();
279	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
280	    &error);
281	g_topology_lock();
282	if (buf == NULL)
283		return (error);
284	/* Decode metadata. */
285	label_metadata_decode(buf, md);
286	g_free(buf);
287
288	return (0);
289}
290
291static void
292g_label_orphan_taste(struct g_consumer *cp __unused)
293{
294
295	KASSERT(1 == 0, ("%s called?", __func__));
296}
297
298static void
299g_label_start_taste(struct bio *bp __unused)
300{
301
302	KASSERT(1 == 0, ("%s called?", __func__));
303}
304
305static int
306g_label_access_taste(struct g_provider *pp __unused, int dr __unused,
307    int dw __unused, int de __unused)
308{
309
310	KASSERT(1 == 0, ("%s called", __func__));
311	return (EOPNOTSUPP);
312}
313
314static struct g_geom *
315g_label_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
316{
317	struct g_label_metadata md;
318	struct g_consumer *cp;
319	struct g_geom *gp;
320	int i;
321
322	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
323	g_topology_assert();
324
325	G_LABEL_DEBUG(2, "Tasting %s.", pp->name);
326
327	/* Skip providers that are already open for writing. */
328	if (pp->acw > 0)
329		return (NULL);
330
331	if (strcmp(pp->geom->class->name, mp->name) == 0)
332		return (NULL);
333
334	gp = g_new_geomf(mp, "label:taste");
335	gp->start = g_label_start_taste;
336	gp->access = g_label_access_taste;
337	gp->orphan = g_label_orphan_taste;
338	cp = g_new_consumer(gp);
339	g_attach(cp, pp);
340	if (g_access(cp, 1, 0, 0) != 0)
341		goto end;
342	do {
343		if (g_label_read_metadata(cp, &md) != 0)
344			break;
345		if (strcmp(md.md_magic, G_LABEL_MAGIC) != 0)
346			break;
347		if (md.md_version > G_LABEL_VERSION) {
348			printf("geom_label.ko module is too old to handle %s.\n",
349			    pp->name);
350			break;
351		}
352
353		/*
354		 * Backward compatibility:
355		 */
356		/*
357		 * There was no md_provsize field in earlier versions of
358		 * metadata.
359		 */
360		if (md.md_version < 2)
361			md.md_provsize = pp->mediasize;
362
363		if (md.md_provsize != pp->mediasize)
364			break;
365
366		g_label_create(NULL, mp, pp, md.md_label, G_LABEL_DIR,
367		    pp->mediasize - pp->sectorsize);
368	} while (0);
369	for (i = 0; g_labels[i] != NULL; i++) {
370		char label[128];
371
372		if (g_labels[i]->ld_enabled == 0)
373			continue;
374		g_topology_unlock();
375		g_labels[i]->ld_taste(cp, label, sizeof(label));
376		g_label_mangle_name(label, sizeof(label));
377		g_topology_lock();
378		if (label[0] == '\0')
379			continue;
380		g_label_create(NULL, mp, pp, label, g_labels[i]->ld_dir,
381		    pp->mediasize);
382	}
383	g_access(cp, -1, 0, 0);
384end:
385	g_detach(cp);
386	g_destroy_consumer(cp);
387	g_destroy_geom(gp);
388	return (NULL);
389}
390
391static void
392g_label_ctl_create(struct gctl_req *req, struct g_class *mp)
393{
394	struct g_provider *pp;
395	const char *name;
396	int *nargs;
397
398	g_topology_assert();
399
400	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
401	if (nargs == NULL) {
402		gctl_error(req, "No '%s' argument", "nargs");
403		return;
404	}
405	if (*nargs != 2) {
406		gctl_error(req, "Invalid number of arguments.");
407		return;
408	}
409	/*
410	 * arg1 is the name of provider.
411	 */
412	name = gctl_get_asciiparam(req, "arg1");
413	if (name == NULL) {
414		gctl_error(req, "No 'arg%d' argument", 1);
415		return;
416	}
417	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
418		name += strlen("/dev/");
419	pp = g_provider_by_name(name);
420	if (pp == NULL) {
421		G_LABEL_DEBUG(1, "Provider %s is invalid.", name);
422		gctl_error(req, "Provider %s is invalid.", name);
423		return;
424	}
425	/*
426	 * arg0 is the label.
427	 */
428	name = gctl_get_asciiparam(req, "arg0");
429	if (name == NULL) {
430		gctl_error(req, "No 'arg%d' argument", 0);
431		return;
432	}
433	g_label_create(req, mp, pp, name, G_LABEL_DIR, pp->mediasize);
434}
435
436static const char *
437g_label_skip_dir(const char *name)
438{
439	char path[64];
440	u_int i;
441
442	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
443		name += strlen("/dev/");
444	if (strncmp(name, G_LABEL_DIR "/", strlen(G_LABEL_DIR "/")) == 0)
445		name += strlen(G_LABEL_DIR "/");
446	for (i = 0; g_labels[i] != NULL; i++) {
447		snprintf(path, sizeof(path), "%s/", g_labels[i]->ld_dir);
448		if (strncmp(name, path, strlen(path)) == 0) {
449			name += strlen(path);
450			break;
451		}
452	}
453	return (name);
454}
455
456static struct g_geom *
457g_label_find_geom(struct g_class *mp, const char *name)
458{
459	struct g_geom *gp;
460	struct g_provider *pp;
461	const char *pname;
462
463	name = g_label_skip_dir(name);
464	LIST_FOREACH(gp, &mp->geom, geom) {
465		pp = LIST_FIRST(&gp->provider);
466		pname = g_label_skip_dir(pp->name);
467		if (strcmp(pname, name) == 0)
468			return (gp);
469	}
470	return (NULL);
471}
472
473static void
474g_label_ctl_destroy(struct gctl_req *req, struct g_class *mp)
475{
476	int *nargs, *force, error, i;
477	struct g_geom *gp;
478	const char *name;
479	char param[16];
480
481	g_topology_assert();
482
483	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
484	if (nargs == NULL) {
485		gctl_error(req, "No '%s' argument", "nargs");
486		return;
487	}
488	if (*nargs <= 0) {
489		gctl_error(req, "Missing device(s).");
490		return;
491	}
492	force = gctl_get_paraml(req, "force", sizeof(*force));
493	if (force == NULL) {
494		gctl_error(req, "No 'force' argument");
495		return;
496	}
497
498	for (i = 0; i < *nargs; i++) {
499		snprintf(param, sizeof(param), "arg%d", i);
500		name = gctl_get_asciiparam(req, param);
501		if (name == NULL) {
502			gctl_error(req, "No 'arg%d' argument", i);
503			return;
504		}
505		gp = g_label_find_geom(mp, name);
506		if (gp == NULL) {
507			G_LABEL_DEBUG(1, "Label %s is invalid.", name);
508			gctl_error(req, "Label %s is invalid.", name);
509			return;
510		}
511		error = g_label_destroy(gp, *force);
512		if (error != 0) {
513			gctl_error(req, "Cannot destroy label %s (error=%d).",
514			    LIST_FIRST(&gp->provider)->name, error);
515			return;
516		}
517	}
518}
519
520static void
521g_label_config(struct gctl_req *req, struct g_class *mp, const char *verb)
522{
523	uint32_t *version;
524
525	g_topology_assert();
526
527	version = gctl_get_paraml(req, "version", sizeof(*version));
528	if (version == NULL) {
529		gctl_error(req, "No '%s' argument.", "version");
530		return;
531	}
532	if (*version != G_LABEL_VERSION) {
533		gctl_error(req, "Userland and kernel parts are out of sync.");
534		return;
535	}
536
537	if (strcmp(verb, "create") == 0) {
538		g_label_ctl_create(req, mp);
539		return;
540	} else if (strcmp(verb, "destroy") == 0 ||
541	    strcmp(verb, "stop") == 0) {
542		g_label_ctl_destroy(req, mp);
543		return;
544	}
545
546	gctl_error(req, "Unknown verb.");
547}
548
549DECLARE_GEOM_CLASS(g_label_class, g_label);
550