xref: /freebsd/sys/compat/linux/linux_mib.c (revision a5ff72cb0e51a7675d4e2b5810a2b6dad5b91960)
1 /*-
2  * Copyright (c) 1999 Marcel Moolenaar
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  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/sdt.h>
35 #include <sys/systm.h>
36 #include <sys/sysctl.h>
37 #include <sys/proc.h>
38 #include <sys/malloc.h>
39 #include <sys/mount.h>
40 #include <sys/jail.h>
41 #include <sys/lock.h>
42 #include <sys/sx.h>
43 
44 #include <compat/linux/linux_mib.h>
45 #include <compat/linux/linux_misc.h>
46 
47 struct linux_prison {
48 	char	pr_osname[LINUX_MAX_UTSNAME];
49 	char	pr_osrelease[LINUX_MAX_UTSNAME];
50 	int	pr_oss_version;
51 	int	pr_osrel;
52 };
53 
54 static struct linux_prison lprison0 = {
55 	.pr_osname =		"Linux",
56 	.pr_osrelease =		LINUX_VERSION_STR,
57 	.pr_oss_version =	0x030600,
58 	.pr_osrel =		LINUX_VERSION_CODE
59 };
60 
61 static unsigned linux_osd_jail_slot;
62 
63 SYSCTL_NODE(_compat, OID_AUTO, linux, CTLFLAG_RW, 0, "Linux mode");
64 
65 static int	linux_set_osname(struct thread *td, char *osname);
66 static int	linux_set_osrelease(struct thread *td, char *osrelease);
67 static int	linux_set_oss_version(struct thread *td, int oss_version);
68 
69 static int
70 linux_sysctl_osname(SYSCTL_HANDLER_ARGS)
71 {
72 	char osname[LINUX_MAX_UTSNAME];
73 	int error;
74 
75 	linux_get_osname(req->td, osname);
76 	error = sysctl_handle_string(oidp, osname, LINUX_MAX_UTSNAME, req);
77 	if (error != 0 || req->newptr == NULL)
78 		return (error);
79 	error = linux_set_osname(req->td, osname);
80 
81 	return (error);
82 }
83 
84 SYSCTL_PROC(_compat_linux, OID_AUTO, osname,
85 	    CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
86 	    0, 0, linux_sysctl_osname, "A",
87 	    "Linux kernel OS name");
88 
89 static int
90 linux_sysctl_osrelease(SYSCTL_HANDLER_ARGS)
91 {
92 	char osrelease[LINUX_MAX_UTSNAME];
93 	int error;
94 
95 	linux_get_osrelease(req->td, osrelease);
96 	error = sysctl_handle_string(oidp, osrelease, LINUX_MAX_UTSNAME, req);
97 	if (error != 0 || req->newptr == NULL)
98 		return (error);
99 	error = linux_set_osrelease(req->td, osrelease);
100 
101 	return (error);
102 }
103 
104 SYSCTL_PROC(_compat_linux, OID_AUTO, osrelease,
105 	    CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
106 	    0, 0, linux_sysctl_osrelease, "A",
107 	    "Linux kernel OS release");
108 
109 static int
110 linux_sysctl_oss_version(SYSCTL_HANDLER_ARGS)
111 {
112 	int oss_version;
113 	int error;
114 
115 	oss_version = linux_get_oss_version(req->td);
116 	error = sysctl_handle_int(oidp, &oss_version, 0, req);
117 	if (error != 0 || req->newptr == NULL)
118 		return (error);
119 	error = linux_set_oss_version(req->td, oss_version);
120 
121 	return (error);
122 }
123 
124 SYSCTL_PROC(_compat_linux, OID_AUTO, oss_version,
125 	    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
126 	    0, 0, linux_sysctl_oss_version, "I",
127 	    "Linux OSS version");
128 
129 /*
130  * Map the osrelease into integer
131  */
132 static int
133 linux_map_osrel(char *osrelease, int *osrel)
134 {
135 	char *sep, *eosrelease;
136 	int len, v0, v1, v2, v;
137 
138 	len = strlen(osrelease);
139 	eosrelease = osrelease + len;
140 	v0 = strtol(osrelease, &sep, 10);
141 	if (osrelease == sep || sep + 1 >= eosrelease || *sep != '.')
142 		return (EINVAL);
143 	osrelease = sep + 1;
144 	v1 = strtol(osrelease, &sep, 10);
145 	if (osrelease == sep || sep + 1 >= eosrelease || *sep != '.')
146 		return (EINVAL);
147 	osrelease = sep + 1;
148 	v2 = strtol(osrelease, &sep, 10);
149 	if (osrelease == sep || sep != eosrelease)
150 		return (EINVAL);
151 
152 	v = v0 * 1000000 + v1 * 1000 + v2;
153 	if (v < 1000000)
154 		return (EINVAL);
155 
156 	*osrel = v;
157 
158 	return (0);
159 }
160 
161 /*
162  * Find a prison with Linux info.
163  * Return the Linux info and the (locked) prison.
164  */
165 static struct linux_prison *
166 linux_find_prison(struct prison *spr, struct prison **prp)
167 {
168 	struct prison *pr;
169 	struct linux_prison *lpr;
170 
171 	for (pr = spr;; pr = pr->pr_parent) {
172 		mtx_lock(&pr->pr_mtx);
173 		lpr = (pr == &prison0)
174 		    ? &lprison0
175 		    : osd_jail_get(pr, linux_osd_jail_slot);
176 		if (lpr != NULL)
177 			break;
178 		mtx_unlock(&pr->pr_mtx);
179 	}
180 	*prp = pr;
181 
182 	return (lpr);
183 }
184 
185 /*
186  * Ensure a prison has its own Linux info.  If lprp is non-null, point it to
187  * the Linux info and lock the prison.
188  */
189 static void
190 linux_alloc_prison(struct prison *pr, struct linux_prison **lprp)
191 {
192 	struct prison *ppr;
193 	struct linux_prison *lpr, *nlpr;
194 	void *rsv;
195 
196 	/* If this prison already has Linux info, return that. */
197 	lpr = linux_find_prison(pr, &ppr);
198 	if (ppr == pr)
199 		goto done;
200 	/*
201 	 * Allocate a new info record.  Then check again, in case something
202 	 * changed during the allocation.
203 	 */
204 	mtx_unlock(&ppr->pr_mtx);
205 	nlpr = malloc(sizeof(struct linux_prison), M_PRISON, M_WAITOK);
206 	rsv = osd_reserve(linux_osd_jail_slot);
207 	lpr = linux_find_prison(pr, &ppr);
208 	if (ppr == pr) {
209 		free(nlpr, M_PRISON);
210 		osd_free_reserved(rsv);
211 		goto done;
212 	}
213 	/* Inherit the initial values from the ancestor. */
214 	mtx_lock(&pr->pr_mtx);
215 	(void)osd_jail_set_reserved(pr, linux_osd_jail_slot, rsv, nlpr);
216 	bcopy(lpr, nlpr, sizeof(*lpr));
217 	lpr = nlpr;
218 	mtx_unlock(&ppr->pr_mtx);
219  done:
220 	if (lprp != NULL)
221 		*lprp = lpr;
222 	else
223 		mtx_unlock(&pr->pr_mtx);
224 }
225 
226 /*
227  * Jail OSD methods for Linux prison data.
228  */
229 static int
230 linux_prison_create(void *obj, void *data)
231 {
232 	struct prison *pr = obj;
233 	struct vfsoptlist *opts = data;
234 	int jsys;
235 
236 	if (vfs_copyopt(opts, "linux", &jsys, sizeof(jsys)) == 0 &&
237 	    jsys == JAIL_SYS_INHERIT)
238 		return (0);
239 	/*
240 	 * Inherit a prison's initial values from its parent
241 	 * (different from JAIL_SYS_INHERIT which also inherits changes).
242 	 */
243 	linux_alloc_prison(pr, NULL);
244 	return (0);
245 }
246 
247 static int
248 linux_prison_check(void *obj __unused, void *data)
249 {
250 	struct vfsoptlist *opts = data;
251 	char *osname, *osrelease;
252 	int error, jsys, len, osrel, oss_version;
253 
254 	/* Check that the parameters are correct. */
255 	error = vfs_copyopt(opts, "linux", &jsys, sizeof(jsys));
256 	if (error != ENOENT) {
257 		if (error != 0)
258 			return (error);
259 		if (jsys != JAIL_SYS_NEW && jsys != JAIL_SYS_INHERIT)
260 			return (EINVAL);
261 	}
262 	error = vfs_getopt(opts, "linux.osname", (void **)&osname, &len);
263 	if (error != ENOENT) {
264 		if (error != 0)
265 			return (error);
266 		if (len == 0 || osname[len - 1] != '\0')
267 			return (EINVAL);
268 		if (len > LINUX_MAX_UTSNAME) {
269 			vfs_opterror(opts, "linux.osname too long");
270 			return (ENAMETOOLONG);
271 		}
272 	}
273 	error = vfs_getopt(opts, "linux.osrelease", (void **)&osrelease, &len);
274 	if (error != ENOENT) {
275 		if (error != 0)
276 			return (error);
277 		if (len == 0 || osrelease[len - 1] != '\0')
278 			return (EINVAL);
279 		if (len > LINUX_MAX_UTSNAME) {
280 			vfs_opterror(opts, "linux.osrelease too long");
281 			return (ENAMETOOLONG);
282 		}
283 		error = linux_map_osrel(osrelease, &osrel);
284 		if (error != 0) {
285 			vfs_opterror(opts, "linux.osrelease format error");
286 			return (error);
287 		}
288 	}
289 	error = vfs_copyopt(opts, "linux.oss_version", &oss_version,
290 	    sizeof(oss_version));
291 
292 	if (error == ENOENT)
293 		error = 0;
294 	return (error);
295 }
296 
297 static int
298 linux_prison_set(void *obj, void *data)
299 {
300 	struct linux_prison *lpr;
301 	struct prison *pr = obj;
302 	struct vfsoptlist *opts = data;
303 	char *osname, *osrelease;
304 	int error, gotversion, jsys, len, oss_version;
305 
306 	/* Set the parameters, which should be correct. */
307 	error = vfs_copyopt(opts, "linux", &jsys, sizeof(jsys));
308 	if (error == ENOENT)
309 		jsys = -1;
310 	error = vfs_getopt(opts, "linux.osname", (void **)&osname, &len);
311 	if (error == ENOENT)
312 		osname = NULL;
313 	else
314 		jsys = JAIL_SYS_NEW;
315 	error = vfs_getopt(opts, "linux.osrelease", (void **)&osrelease, &len);
316 	if (error == ENOENT)
317 		osrelease = NULL;
318 	else
319 		jsys = JAIL_SYS_NEW;
320 	error = vfs_copyopt(opts, "linux.oss_version", &oss_version,
321 	    sizeof(oss_version));
322 	if (error == ENOENT)
323 		gotversion = 0;
324 	else {
325 		gotversion = 1;
326 		jsys = JAIL_SYS_NEW;
327 	}
328 	switch (jsys) {
329 	case JAIL_SYS_INHERIT:
330 		/* "linux=inherit": inherit the parent's Linux info. */
331 		mtx_lock(&pr->pr_mtx);
332 		osd_jail_del(pr, linux_osd_jail_slot);
333 		mtx_unlock(&pr->pr_mtx);
334 		break;
335 	case JAIL_SYS_NEW:
336 		/*
337 		 * "linux=new" or "linux.*":
338 		 * the prison gets its own Linux info.
339 		 */
340 		linux_alloc_prison(pr, &lpr);
341 		if (osrelease) {
342 			error = linux_map_osrel(osrelease, &lpr->pr_osrel);
343 			if (error) {
344 				mtx_unlock(&pr->pr_mtx);
345 				return (error);
346 			}
347 			strlcpy(lpr->pr_osrelease, osrelease,
348 			    LINUX_MAX_UTSNAME);
349 		}
350 		if (osname)
351 			strlcpy(lpr->pr_osname, osname, LINUX_MAX_UTSNAME);
352 		if (gotversion)
353 			lpr->pr_oss_version = oss_version;
354 		mtx_unlock(&pr->pr_mtx);
355 	}
356 
357 	return (0);
358 }
359 
360 SYSCTL_JAIL_PARAM_SYS_NODE(linux, CTLFLAG_RW, "Jail Linux parameters");
361 SYSCTL_JAIL_PARAM_STRING(_linux, osname, CTLFLAG_RW, LINUX_MAX_UTSNAME,
362     "Jail Linux kernel OS name");
363 SYSCTL_JAIL_PARAM_STRING(_linux, osrelease, CTLFLAG_RW, LINUX_MAX_UTSNAME,
364     "Jail Linux kernel OS release");
365 SYSCTL_JAIL_PARAM(_linux, oss_version, CTLTYPE_INT | CTLFLAG_RW,
366     "I", "Jail Linux OSS version");
367 
368 static int
369 linux_prison_get(void *obj, void *data)
370 {
371 	struct linux_prison *lpr;
372 	struct prison *ppr;
373 	struct prison *pr = obj;
374 	struct vfsoptlist *opts = data;
375 	int error, i;
376 
377 	static int version0;
378 
379 	/* See if this prison is the one with the Linux info. */
380 	lpr = linux_find_prison(pr, &ppr);
381 	i = (ppr == pr) ? JAIL_SYS_NEW : JAIL_SYS_INHERIT;
382 	error = vfs_setopt(opts, "linux", &i, sizeof(i));
383 	if (error != 0 && error != ENOENT)
384 		goto done;
385 	if (i) {
386 		error = vfs_setopts(opts, "linux.osname", lpr->pr_osname);
387 		if (error != 0 && error != ENOENT)
388 			goto done;
389 		error = vfs_setopts(opts, "linux.osrelease", lpr->pr_osrelease);
390 		if (error != 0 && error != ENOENT)
391 			goto done;
392 		error = vfs_setopt(opts, "linux.oss_version",
393 		    &lpr->pr_oss_version, sizeof(lpr->pr_oss_version));
394 		if (error != 0 && error != ENOENT)
395 			goto done;
396 	} else {
397 		/*
398 		 * If this prison is inheriting its Linux info, report
399 		 * empty/zero parameters.
400 		 */
401 		error = vfs_setopts(opts, "linux.osname", "");
402 		if (error != 0 && error != ENOENT)
403 			goto done;
404 		error = vfs_setopts(opts, "linux.osrelease", "");
405 		if (error != 0 && error != ENOENT)
406 			goto done;
407 		error = vfs_setopt(opts, "linux.oss_version", &version0,
408 		    sizeof(lpr->pr_oss_version));
409 		if (error != 0 && error != ENOENT)
410 			goto done;
411 	}
412 	error = 0;
413 
414  done:
415 	mtx_unlock(&ppr->pr_mtx);
416 
417 	return (error);
418 }
419 
420 static void
421 linux_prison_destructor(void *data)
422 {
423 
424 	free(data, M_PRISON);
425 }
426 
427 void
428 linux_osd_jail_register(void)
429 {
430 	struct prison *pr;
431 	osd_method_t methods[PR_MAXMETHOD] = {
432 	    [PR_METHOD_CREATE] =	linux_prison_create,
433 	    [PR_METHOD_GET] =		linux_prison_get,
434 	    [PR_METHOD_SET] =		linux_prison_set,
435 	    [PR_METHOD_CHECK] =		linux_prison_check
436 	};
437 
438 	linux_osd_jail_slot =
439 	    osd_jail_register(linux_prison_destructor, methods);
440 	/* Copy the system linux info to any current prisons. */
441 	sx_slock(&allprison_lock);
442 	TAILQ_FOREACH(pr, &allprison, pr_list)
443 		linux_alloc_prison(pr, NULL);
444 	sx_sunlock(&allprison_lock);
445 }
446 
447 void
448 linux_osd_jail_deregister(void)
449 {
450 
451 	osd_jail_deregister(linux_osd_jail_slot);
452 }
453 
454 void
455 linux_get_osname(struct thread *td, char *dst)
456 {
457 	struct prison *pr;
458 	struct linux_prison *lpr;
459 
460 	lpr = linux_find_prison(td->td_ucred->cr_prison, &pr);
461 	bcopy(lpr->pr_osname, dst, LINUX_MAX_UTSNAME);
462 	mtx_unlock(&pr->pr_mtx);
463 }
464 
465 static int
466 linux_set_osname(struct thread *td, char *osname)
467 {
468 	struct prison *pr;
469 	struct linux_prison *lpr;
470 
471 	lpr = linux_find_prison(td->td_ucred->cr_prison, &pr);
472 	strlcpy(lpr->pr_osname, osname, LINUX_MAX_UTSNAME);
473 	mtx_unlock(&pr->pr_mtx);
474 
475 	return (0);
476 }
477 
478 void
479 linux_get_osrelease(struct thread *td, char *dst)
480 {
481 	struct prison *pr;
482 	struct linux_prison *lpr;
483 
484 	lpr = linux_find_prison(td->td_ucred->cr_prison, &pr);
485 	bcopy(lpr->pr_osrelease, dst, LINUX_MAX_UTSNAME);
486 	mtx_unlock(&pr->pr_mtx);
487 }
488 
489 int
490 linux_kernver(struct thread *td)
491 {
492 	struct prison *pr;
493 	struct linux_prison *lpr;
494 	int osrel;
495 
496 	lpr = linux_find_prison(td->td_ucred->cr_prison, &pr);
497 	osrel = lpr->pr_osrel;
498 	mtx_unlock(&pr->pr_mtx);
499 
500 	return (osrel);
501 }
502 
503 static int
504 linux_set_osrelease(struct thread *td, char *osrelease)
505 {
506 	struct prison *pr;
507 	struct linux_prison *lpr;
508 	int error;
509 
510 	lpr = linux_find_prison(td->td_ucred->cr_prison, &pr);
511 	error = linux_map_osrel(osrelease, &lpr->pr_osrel);
512 	if (error == 0)
513 		strlcpy(lpr->pr_osrelease, osrelease, LINUX_MAX_UTSNAME);
514 	mtx_unlock(&pr->pr_mtx);
515 
516 	return (error);
517 }
518 
519 int
520 linux_get_oss_version(struct thread *td)
521 {
522 	struct prison *pr;
523 	struct linux_prison *lpr;
524 	int version;
525 
526 	lpr = linux_find_prison(td->td_ucred->cr_prison, &pr);
527 	version = lpr->pr_oss_version;
528 	mtx_unlock(&pr->pr_mtx);
529 
530 	return (version);
531 }
532 
533 static int
534 linux_set_oss_version(struct thread *td, int oss_version)
535 {
536 	struct prison *pr;
537 	struct linux_prison *lpr;
538 
539 	lpr = linux_find_prison(td->td_ucred->cr_prison, &pr);
540 	lpr->pr_oss_version = oss_version;
541 	mtx_unlock(&pr->pr_mtx);
542 
543 	return (0);
544 }
545