xref: /linux/security/selinux/selinuxfs.c (revision 2b8232ce512105e28453f301d1510de8363bccd1)
1 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
2  *
3  * 	Added conditional policy language extensions
4  *
5  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
6  * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
7  *	This program is free software; you can redistribute it and/or modify
8  *  	it under the terms of the GNU General Public License as published by
9  *	the Free Software Foundation, version 2.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/pagemap.h>
14 #include <linux/slab.h>
15 #include <linux/vmalloc.h>
16 #include <linux/fs.h>
17 #include <linux/mutex.h>
18 #include <linux/init.h>
19 #include <linux/string.h>
20 #include <linux/security.h>
21 #include <linux/major.h>
22 #include <linux/seq_file.h>
23 #include <linux/percpu.h>
24 #include <linux/audit.h>
25 #include <asm/uaccess.h>
26 #include <asm/semaphore.h>
27 
28 /* selinuxfs pseudo filesystem for exporting the security policy API.
29    Based on the proc code and the fs/nfsd/nfsctl.c code. */
30 
31 #include "flask.h"
32 #include "avc.h"
33 #include "avc_ss.h"
34 #include "security.h"
35 #include "objsec.h"
36 #include "conditional.h"
37 
38 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
39 
40 #ifdef CONFIG_SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT
41 #define SELINUX_COMPAT_NET_VALUE 0
42 #else
43 #define SELINUX_COMPAT_NET_VALUE 1
44 #endif
45 
46 int selinux_compat_net = SELINUX_COMPAT_NET_VALUE;
47 
48 static int __init checkreqprot_setup(char *str)
49 {
50 	selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0;
51 	return 1;
52 }
53 __setup("checkreqprot=", checkreqprot_setup);
54 
55 static int __init selinux_compat_net_setup(char *str)
56 {
57 	selinux_compat_net = simple_strtoul(str,NULL,0) ? 1 : 0;
58 	return 1;
59 }
60 __setup("selinux_compat_net=", selinux_compat_net_setup);
61 
62 
63 static DEFINE_MUTEX(sel_mutex);
64 
65 /* global data for booleans */
66 static struct dentry *bool_dir = NULL;
67 static int bool_num = 0;
68 static int *bool_pending_values = NULL;
69 
70 /* global data for classes */
71 static struct dentry *class_dir = NULL;
72 static unsigned long last_class_ino;
73 
74 extern void selnl_notify_setenforce(int val);
75 
76 /* Check whether a task is allowed to use a security operation. */
77 static int task_has_security(struct task_struct *tsk,
78 			     u32 perms)
79 {
80 	struct task_security_struct *tsec;
81 
82 	tsec = tsk->security;
83 	if (!tsec)
84 		return -EACCES;
85 
86 	return avc_has_perm(tsec->sid, SECINITSID_SECURITY,
87 			    SECCLASS_SECURITY, perms, NULL);
88 }
89 
90 enum sel_inos {
91 	SEL_ROOT_INO = 2,
92 	SEL_LOAD,	/* load policy */
93 	SEL_ENFORCE,	/* get or set enforcing status */
94 	SEL_CONTEXT,	/* validate context */
95 	SEL_ACCESS,	/* compute access decision */
96 	SEL_CREATE,	/* compute create labeling decision */
97 	SEL_RELABEL,	/* compute relabeling decision */
98 	SEL_USER,	/* compute reachable user contexts */
99 	SEL_POLICYVERS,	/* return policy version for this kernel */
100 	SEL_COMMIT_BOOLS, /* commit new boolean values */
101 	SEL_MLS,	/* return if MLS policy is enabled */
102 	SEL_DISABLE,	/* disable SELinux until next reboot */
103 	SEL_MEMBER,	/* compute polyinstantiation membership decision */
104 	SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
105 	SEL_COMPAT_NET,	/* whether to use old compat network packet controls */
106 	SEL_INO_NEXT,	/* The next inode number to use */
107 };
108 
109 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
110 
111 #define SEL_INITCON_INO_OFFSET 	0x01000000
112 #define SEL_BOOL_INO_OFFSET	0x02000000
113 #define SEL_CLASS_INO_OFFSET	0x04000000
114 #define SEL_INO_MASK		0x00ffffff
115 
116 #define TMPBUFLEN	12
117 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
118 				size_t count, loff_t *ppos)
119 {
120 	char tmpbuf[TMPBUFLEN];
121 	ssize_t length;
122 
123 	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
124 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
125 }
126 
127 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
128 static ssize_t sel_write_enforce(struct file * file, const char __user * buf,
129 				 size_t count, loff_t *ppos)
130 
131 {
132 	char *page;
133 	ssize_t length;
134 	int new_value;
135 
136 	if (count >= PAGE_SIZE)
137 		return -ENOMEM;
138 	if (*ppos != 0) {
139 		/* No partial writes. */
140 		return -EINVAL;
141 	}
142 	page = (char*)get_zeroed_page(GFP_KERNEL);
143 	if (!page)
144 		return -ENOMEM;
145 	length = -EFAULT;
146 	if (copy_from_user(page, buf, count))
147 		goto out;
148 
149 	length = -EINVAL;
150 	if (sscanf(page, "%d", &new_value) != 1)
151 		goto out;
152 
153 	if (new_value != selinux_enforcing) {
154 		length = task_has_security(current, SECURITY__SETENFORCE);
155 		if (length)
156 			goto out;
157 		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
158 			"enforcing=%d old_enforcing=%d auid=%u", new_value,
159 			selinux_enforcing,
160 			audit_get_loginuid(current->audit_context));
161 		selinux_enforcing = new_value;
162 		if (selinux_enforcing)
163 			avc_ss_reset(0);
164 		selnl_notify_setenforce(selinux_enforcing);
165 	}
166 	length = count;
167 out:
168 	free_page((unsigned long) page);
169 	return length;
170 }
171 #else
172 #define sel_write_enforce NULL
173 #endif
174 
175 static const struct file_operations sel_enforce_ops = {
176 	.read		= sel_read_enforce,
177 	.write		= sel_write_enforce,
178 };
179 
180 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
181 static ssize_t sel_write_disable(struct file * file, const char __user * buf,
182 				 size_t count, loff_t *ppos)
183 
184 {
185 	char *page;
186 	ssize_t length;
187 	int new_value;
188 	extern int selinux_disable(void);
189 
190 	if (count >= PAGE_SIZE)
191 		return -ENOMEM;
192 	if (*ppos != 0) {
193 		/* No partial writes. */
194 		return -EINVAL;
195 	}
196 	page = (char*)get_zeroed_page(GFP_KERNEL);
197 	if (!page)
198 		return -ENOMEM;
199 	length = -EFAULT;
200 	if (copy_from_user(page, buf, count))
201 		goto out;
202 
203 	length = -EINVAL;
204 	if (sscanf(page, "%d", &new_value) != 1)
205 		goto out;
206 
207 	if (new_value) {
208 		length = selinux_disable();
209 		if (length < 0)
210 			goto out;
211 		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
212 			"selinux=0 auid=%u",
213 			audit_get_loginuid(current->audit_context));
214 	}
215 
216 	length = count;
217 out:
218 	free_page((unsigned long) page);
219 	return length;
220 }
221 #else
222 #define sel_write_disable NULL
223 #endif
224 
225 static const struct file_operations sel_disable_ops = {
226 	.write		= sel_write_disable,
227 };
228 
229 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
230                                    size_t count, loff_t *ppos)
231 {
232 	char tmpbuf[TMPBUFLEN];
233 	ssize_t length;
234 
235 	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
236 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
237 }
238 
239 static const struct file_operations sel_policyvers_ops = {
240 	.read		= sel_read_policyvers,
241 };
242 
243 /* declaration for sel_write_load */
244 static int sel_make_bools(void);
245 static int sel_make_classes(void);
246 
247 /* declaration for sel_make_class_dirs */
248 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
249 			unsigned long *ino);
250 
251 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
252 				size_t count, loff_t *ppos)
253 {
254 	char tmpbuf[TMPBUFLEN];
255 	ssize_t length;
256 
257 	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
258 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
259 }
260 
261 static const struct file_operations sel_mls_ops = {
262 	.read		= sel_read_mls,
263 };
264 
265 static ssize_t sel_write_load(struct file * file, const char __user * buf,
266 			      size_t count, loff_t *ppos)
267 
268 {
269 	int ret;
270 	ssize_t length;
271 	void *data = NULL;
272 
273 	mutex_lock(&sel_mutex);
274 
275 	length = task_has_security(current, SECURITY__LOAD_POLICY);
276 	if (length)
277 		goto out;
278 
279 	if (*ppos != 0) {
280 		/* No partial writes. */
281 		length = -EINVAL;
282 		goto out;
283 	}
284 
285 	if ((count > 64 * 1024 * 1024)
286 	    || (data = vmalloc(count)) == NULL) {
287 		length = -ENOMEM;
288 		goto out;
289 	}
290 
291 	length = -EFAULT;
292 	if (copy_from_user(data, buf, count) != 0)
293 		goto out;
294 
295 	length = security_load_policy(data, count);
296 	if (length)
297 		goto out;
298 
299 	ret = sel_make_bools();
300 	if (ret) {
301 		length = ret;
302 		goto out1;
303 	}
304 
305 	ret = sel_make_classes();
306 	if (ret)
307 		length = ret;
308 	else
309 		length = count;
310 
311 out1:
312 	audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
313 		"policy loaded auid=%u",
314 		audit_get_loginuid(current->audit_context));
315 out:
316 	mutex_unlock(&sel_mutex);
317 	vfree(data);
318 	return length;
319 }
320 
321 static const struct file_operations sel_load_ops = {
322 	.write		= sel_write_load,
323 };
324 
325 static ssize_t sel_write_context(struct file * file, char *buf, size_t size)
326 {
327 	char *canon;
328 	u32 sid, len;
329 	ssize_t length;
330 
331 	length = task_has_security(current, SECURITY__CHECK_CONTEXT);
332 	if (length)
333 		return length;
334 
335 	length = security_context_to_sid(buf, size, &sid);
336 	if (length < 0)
337 		return length;
338 
339 	length = security_sid_to_context(sid, &canon, &len);
340 	if (length < 0)
341 		return length;
342 
343 	if (len > SIMPLE_TRANSACTION_LIMIT) {
344 		printk(KERN_ERR "%s:  context size (%u) exceeds payload "
345 		       "max\n", __FUNCTION__, len);
346 		length = -ERANGE;
347 		goto out;
348 	}
349 
350 	memcpy(buf, canon, len);
351 	length = len;
352 out:
353 	kfree(canon);
354 	return length;
355 }
356 
357 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
358 				     size_t count, loff_t *ppos)
359 {
360 	char tmpbuf[TMPBUFLEN];
361 	ssize_t length;
362 
363 	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
364 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
365 }
366 
367 static ssize_t sel_write_checkreqprot(struct file * file, const char __user * buf,
368 				      size_t count, loff_t *ppos)
369 {
370 	char *page;
371 	ssize_t length;
372 	unsigned int new_value;
373 
374 	length = task_has_security(current, SECURITY__SETCHECKREQPROT);
375 	if (length)
376 		return length;
377 
378 	if (count >= PAGE_SIZE)
379 		return -ENOMEM;
380 	if (*ppos != 0) {
381 		/* No partial writes. */
382 		return -EINVAL;
383 	}
384 	page = (char*)get_zeroed_page(GFP_KERNEL);
385 	if (!page)
386 		return -ENOMEM;
387 	length = -EFAULT;
388 	if (copy_from_user(page, buf, count))
389 		goto out;
390 
391 	length = -EINVAL;
392 	if (sscanf(page, "%u", &new_value) != 1)
393 		goto out;
394 
395 	selinux_checkreqprot = new_value ? 1 : 0;
396 	length = count;
397 out:
398 	free_page((unsigned long) page);
399 	return length;
400 }
401 static const struct file_operations sel_checkreqprot_ops = {
402 	.read		= sel_read_checkreqprot,
403 	.write		= sel_write_checkreqprot,
404 };
405 
406 static ssize_t sel_read_compat_net(struct file *filp, char __user *buf,
407 				   size_t count, loff_t *ppos)
408 {
409 	char tmpbuf[TMPBUFLEN];
410 	ssize_t length;
411 
412 	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_compat_net);
413 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
414 }
415 
416 static ssize_t sel_write_compat_net(struct file * file, const char __user * buf,
417 				    size_t count, loff_t *ppos)
418 {
419 	char *page;
420 	ssize_t length;
421 	int new_value;
422 
423 	length = task_has_security(current, SECURITY__LOAD_POLICY);
424 	if (length)
425 		return length;
426 
427 	if (count >= PAGE_SIZE)
428 		return -ENOMEM;
429 	if (*ppos != 0) {
430 		/* No partial writes. */
431 		return -EINVAL;
432 	}
433 	page = (char*)get_zeroed_page(GFP_KERNEL);
434 	if (!page)
435 		return -ENOMEM;
436 	length = -EFAULT;
437 	if (copy_from_user(page, buf, count))
438 		goto out;
439 
440 	length = -EINVAL;
441 	if (sscanf(page, "%d", &new_value) != 1)
442 		goto out;
443 
444 	selinux_compat_net = new_value ? 1 : 0;
445 	length = count;
446 out:
447 	free_page((unsigned long) page);
448 	return length;
449 }
450 static const struct file_operations sel_compat_net_ops = {
451 	.read		= sel_read_compat_net,
452 	.write		= sel_write_compat_net,
453 };
454 
455 /*
456  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
457  */
458 static ssize_t sel_write_access(struct file * file, char *buf, size_t size);
459 static ssize_t sel_write_create(struct file * file, char *buf, size_t size);
460 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size);
461 static ssize_t sel_write_user(struct file * file, char *buf, size_t size);
462 static ssize_t sel_write_member(struct file * file, char *buf, size_t size);
463 
464 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
465 	[SEL_ACCESS] = sel_write_access,
466 	[SEL_CREATE] = sel_write_create,
467 	[SEL_RELABEL] = sel_write_relabel,
468 	[SEL_USER] = sel_write_user,
469 	[SEL_MEMBER] = sel_write_member,
470 	[SEL_CONTEXT] = sel_write_context,
471 };
472 
473 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
474 {
475 	ino_t ino =  file->f_path.dentry->d_inode->i_ino;
476 	char *data;
477 	ssize_t rv;
478 
479 	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
480 		return -EINVAL;
481 
482 	data = simple_transaction_get(file, buf, size);
483 	if (IS_ERR(data))
484 		return PTR_ERR(data);
485 
486 	rv =  write_op[ino](file, data, size);
487 	if (rv>0) {
488 		simple_transaction_set(file, rv);
489 		rv = size;
490 	}
491 	return rv;
492 }
493 
494 static const struct file_operations transaction_ops = {
495 	.write		= selinux_transaction_write,
496 	.read		= simple_transaction_read,
497 	.release	= simple_transaction_release,
498 };
499 
500 /*
501  * payload - write methods
502  * If the method has a response, the response should be put in buf,
503  * and the length returned.  Otherwise return 0 or and -error.
504  */
505 
506 static ssize_t sel_write_access(struct file * file, char *buf, size_t size)
507 {
508 	char *scon, *tcon;
509 	u32 ssid, tsid;
510 	u16 tclass;
511 	u32 req;
512 	struct av_decision avd;
513 	ssize_t length;
514 
515 	length = task_has_security(current, SECURITY__COMPUTE_AV);
516 	if (length)
517 		return length;
518 
519 	length = -ENOMEM;
520 	scon = kzalloc(size+1, GFP_KERNEL);
521 	if (!scon)
522 		return length;
523 
524 	tcon = kzalloc(size+1, GFP_KERNEL);
525 	if (!tcon)
526 		goto out;
527 
528 	length = -EINVAL;
529 	if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
530 		goto out2;
531 
532 	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
533 	if (length < 0)
534 		goto out2;
535 	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
536 	if (length < 0)
537 		goto out2;
538 
539 	length = security_compute_av(ssid, tsid, tclass, req, &avd);
540 	if (length < 0)
541 		goto out2;
542 
543 	length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
544 			  "%x %x %x %x %u",
545 			  avd.allowed, avd.decided,
546 			  avd.auditallow, avd.auditdeny,
547 			  avd.seqno);
548 out2:
549 	kfree(tcon);
550 out:
551 	kfree(scon);
552 	return length;
553 }
554 
555 static ssize_t sel_write_create(struct file * file, char *buf, size_t size)
556 {
557 	char *scon, *tcon;
558 	u32 ssid, tsid, newsid;
559 	u16 tclass;
560 	ssize_t length;
561 	char *newcon;
562 	u32 len;
563 
564 	length = task_has_security(current, SECURITY__COMPUTE_CREATE);
565 	if (length)
566 		return length;
567 
568 	length = -ENOMEM;
569 	scon = kzalloc(size+1, GFP_KERNEL);
570 	if (!scon)
571 		return length;
572 
573 	tcon = kzalloc(size+1, GFP_KERNEL);
574 	if (!tcon)
575 		goto out;
576 
577 	length = -EINVAL;
578 	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
579 		goto out2;
580 
581 	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
582 	if (length < 0)
583 		goto out2;
584 	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
585 	if (length < 0)
586 		goto out2;
587 
588 	length = security_transition_sid(ssid, tsid, tclass, &newsid);
589 	if (length < 0)
590 		goto out2;
591 
592 	length = security_sid_to_context(newsid, &newcon, &len);
593 	if (length < 0)
594 		goto out2;
595 
596 	if (len > SIMPLE_TRANSACTION_LIMIT) {
597 		printk(KERN_ERR "%s:  context size (%u) exceeds payload "
598 		       "max\n", __FUNCTION__, len);
599 		length = -ERANGE;
600 		goto out3;
601 	}
602 
603 	memcpy(buf, newcon, len);
604 	length = len;
605 out3:
606 	kfree(newcon);
607 out2:
608 	kfree(tcon);
609 out:
610 	kfree(scon);
611 	return length;
612 }
613 
614 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size)
615 {
616 	char *scon, *tcon;
617 	u32 ssid, tsid, newsid;
618 	u16 tclass;
619 	ssize_t length;
620 	char *newcon;
621 	u32 len;
622 
623 	length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
624 	if (length)
625 		return length;
626 
627 	length = -ENOMEM;
628 	scon = kzalloc(size+1, GFP_KERNEL);
629 	if (!scon)
630 		return length;
631 
632 	tcon = kzalloc(size+1, GFP_KERNEL);
633 	if (!tcon)
634 		goto out;
635 
636 	length = -EINVAL;
637 	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
638 		goto out2;
639 
640 	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
641 	if (length < 0)
642 		goto out2;
643 	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
644 	if (length < 0)
645 		goto out2;
646 
647 	length = security_change_sid(ssid, tsid, tclass, &newsid);
648 	if (length < 0)
649 		goto out2;
650 
651 	length = security_sid_to_context(newsid, &newcon, &len);
652 	if (length < 0)
653 		goto out2;
654 
655 	if (len > SIMPLE_TRANSACTION_LIMIT) {
656 		length = -ERANGE;
657 		goto out3;
658 	}
659 
660 	memcpy(buf, newcon, len);
661 	length = len;
662 out3:
663 	kfree(newcon);
664 out2:
665 	kfree(tcon);
666 out:
667 	kfree(scon);
668 	return length;
669 }
670 
671 static ssize_t sel_write_user(struct file * file, char *buf, size_t size)
672 {
673 	char *con, *user, *ptr;
674 	u32 sid, *sids;
675 	ssize_t length;
676 	char *newcon;
677 	int i, rc;
678 	u32 len, nsids;
679 
680 	length = task_has_security(current, SECURITY__COMPUTE_USER);
681 	if (length)
682 		return length;
683 
684 	length = -ENOMEM;
685 	con = kzalloc(size+1, GFP_KERNEL);
686 	if (!con)
687 		return length;
688 
689 	user = kzalloc(size+1, GFP_KERNEL);
690 	if (!user)
691 		goto out;
692 
693 	length = -EINVAL;
694 	if (sscanf(buf, "%s %s", con, user) != 2)
695 		goto out2;
696 
697 	length = security_context_to_sid(con, strlen(con)+1, &sid);
698 	if (length < 0)
699 		goto out2;
700 
701 	length = security_get_user_sids(sid, user, &sids, &nsids);
702 	if (length < 0)
703 		goto out2;
704 
705 	length = sprintf(buf, "%u", nsids) + 1;
706 	ptr = buf + length;
707 	for (i = 0; i < nsids; i++) {
708 		rc = security_sid_to_context(sids[i], &newcon, &len);
709 		if (rc) {
710 			length = rc;
711 			goto out3;
712 		}
713 		if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
714 			kfree(newcon);
715 			length = -ERANGE;
716 			goto out3;
717 		}
718 		memcpy(ptr, newcon, len);
719 		kfree(newcon);
720 		ptr += len;
721 		length += len;
722 	}
723 out3:
724 	kfree(sids);
725 out2:
726 	kfree(user);
727 out:
728 	kfree(con);
729 	return length;
730 }
731 
732 static ssize_t sel_write_member(struct file * file, char *buf, size_t size)
733 {
734 	char *scon, *tcon;
735 	u32 ssid, tsid, newsid;
736 	u16 tclass;
737 	ssize_t length;
738 	char *newcon;
739 	u32 len;
740 
741 	length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
742 	if (length)
743 		return length;
744 
745 	length = -ENOMEM;
746 	scon = kzalloc(size+1, GFP_KERNEL);
747 	if (!scon)
748 		return length;
749 
750 	tcon = kzalloc(size+1, GFP_KERNEL);
751 	if (!tcon)
752 		goto out;
753 
754 	length = -EINVAL;
755 	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
756 		goto out2;
757 
758 	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
759 	if (length < 0)
760 		goto out2;
761 	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
762 	if (length < 0)
763 		goto out2;
764 
765 	length = security_member_sid(ssid, tsid, tclass, &newsid);
766 	if (length < 0)
767 		goto out2;
768 
769 	length = security_sid_to_context(newsid, &newcon, &len);
770 	if (length < 0)
771 		goto out2;
772 
773 	if (len > SIMPLE_TRANSACTION_LIMIT) {
774 		printk(KERN_ERR "%s:  context size (%u) exceeds payload "
775 		       "max\n", __FUNCTION__, len);
776 		length = -ERANGE;
777 		goto out3;
778 	}
779 
780 	memcpy(buf, newcon, len);
781 	length = len;
782 out3:
783 	kfree(newcon);
784 out2:
785 	kfree(tcon);
786 out:
787 	kfree(scon);
788 	return length;
789 }
790 
791 static struct inode *sel_make_inode(struct super_block *sb, int mode)
792 {
793 	struct inode *ret = new_inode(sb);
794 
795 	if (ret) {
796 		ret->i_mode = mode;
797 		ret->i_uid = ret->i_gid = 0;
798 		ret->i_blocks = 0;
799 		ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
800 	}
801 	return ret;
802 }
803 
804 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
805 			     size_t count, loff_t *ppos)
806 {
807 	char *page = NULL;
808 	ssize_t length;
809 	ssize_t ret;
810 	int cur_enforcing;
811 	struct inode *inode;
812 
813 	mutex_lock(&sel_mutex);
814 
815 	ret = -EFAULT;
816 
817 	/* check to see if this file has been deleted */
818 	if (!filep->f_op)
819 		goto out;
820 
821 	if (count > PAGE_SIZE) {
822 		ret = -EINVAL;
823 		goto out;
824 	}
825 	if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) {
826 		ret = -ENOMEM;
827 		goto out;
828 	}
829 
830 	inode = filep->f_path.dentry->d_inode;
831 	cur_enforcing = security_get_bool_value(inode->i_ino&SEL_INO_MASK);
832 	if (cur_enforcing < 0) {
833 		ret = cur_enforcing;
834 		goto out;
835 	}
836 
837 	length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
838 			  bool_pending_values[inode->i_ino&SEL_INO_MASK]);
839 	ret = simple_read_from_buffer(buf, count, ppos, page, length);
840 out:
841 	mutex_unlock(&sel_mutex);
842 	if (page)
843 		free_page((unsigned long)page);
844 	return ret;
845 }
846 
847 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
848 			      size_t count, loff_t *ppos)
849 {
850 	char *page = NULL;
851 	ssize_t length = -EFAULT;
852 	int new_value;
853 	struct inode *inode;
854 
855 	mutex_lock(&sel_mutex);
856 
857 	length = task_has_security(current, SECURITY__SETBOOL);
858 	if (length)
859 		goto out;
860 
861 	/* check to see if this file has been deleted */
862 	if (!filep->f_op)
863 		goto out;
864 
865 	if (count >= PAGE_SIZE) {
866 		length = -ENOMEM;
867 		goto out;
868 	}
869 	if (*ppos != 0) {
870 		/* No partial writes. */
871 		goto out;
872 	}
873 	page = (char*)get_zeroed_page(GFP_KERNEL);
874 	if (!page) {
875 		length = -ENOMEM;
876 		goto out;
877 	}
878 
879 	if (copy_from_user(page, buf, count))
880 		goto out;
881 
882 	length = -EINVAL;
883 	if (sscanf(page, "%d", &new_value) != 1)
884 		goto out;
885 
886 	if (new_value)
887 		new_value = 1;
888 
889 	inode = filep->f_path.dentry->d_inode;
890 	bool_pending_values[inode->i_ino&SEL_INO_MASK] = new_value;
891 	length = count;
892 
893 out:
894 	mutex_unlock(&sel_mutex);
895 	if (page)
896 		free_page((unsigned long) page);
897 	return length;
898 }
899 
900 static const struct file_operations sel_bool_ops = {
901 	.read           = sel_read_bool,
902 	.write          = sel_write_bool,
903 };
904 
905 static ssize_t sel_commit_bools_write(struct file *filep,
906 				      const char __user *buf,
907 				      size_t count, loff_t *ppos)
908 {
909 	char *page = NULL;
910 	ssize_t length = -EFAULT;
911 	int new_value;
912 
913 	mutex_lock(&sel_mutex);
914 
915 	length = task_has_security(current, SECURITY__SETBOOL);
916 	if (length)
917 		goto out;
918 
919 	/* check to see if this file has been deleted */
920 	if (!filep->f_op)
921 		goto out;
922 
923 	if (count >= PAGE_SIZE) {
924 		length = -ENOMEM;
925 		goto out;
926 	}
927 	if (*ppos != 0) {
928 		/* No partial writes. */
929 		goto out;
930 	}
931 	page = (char*)get_zeroed_page(GFP_KERNEL);
932 	if (!page) {
933 		length = -ENOMEM;
934 		goto out;
935 	}
936 
937 	if (copy_from_user(page, buf, count))
938 		goto out;
939 
940 	length = -EINVAL;
941 	if (sscanf(page, "%d", &new_value) != 1)
942 		goto out;
943 
944 	if (new_value && bool_pending_values) {
945 		security_set_bools(bool_num, bool_pending_values);
946 	}
947 
948 	length = count;
949 
950 out:
951 	mutex_unlock(&sel_mutex);
952 	if (page)
953 		free_page((unsigned long) page);
954 	return length;
955 }
956 
957 static const struct file_operations sel_commit_bools_ops = {
958 	.write          = sel_commit_bools_write,
959 };
960 
961 /* partial revoke() from fs/proc/generic.c proc_kill_inodes */
962 static void sel_remove_entries(struct dentry *de)
963 {
964 	struct list_head *p, *node;
965 	struct super_block *sb = de->d_sb;
966 
967 	spin_lock(&dcache_lock);
968 	node = de->d_subdirs.next;
969 	while (node != &de->d_subdirs) {
970 		struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
971 		list_del_init(node);
972 
973 		if (d->d_inode) {
974 			d = dget_locked(d);
975 			spin_unlock(&dcache_lock);
976 			d_delete(d);
977 			simple_unlink(de->d_inode, d);
978 			dput(d);
979 			spin_lock(&dcache_lock);
980 		}
981 		node = de->d_subdirs.next;
982 	}
983 
984 	spin_unlock(&dcache_lock);
985 
986 	file_list_lock();
987 	list_for_each(p, &sb->s_files) {
988 		struct file * filp = list_entry(p, struct file, f_u.fu_list);
989 		struct dentry * dentry = filp->f_path.dentry;
990 
991 		if (dentry->d_parent != de) {
992 			continue;
993 		}
994 		filp->f_op = NULL;
995 	}
996 	file_list_unlock();
997 }
998 
999 #define BOOL_DIR_NAME "booleans"
1000 
1001 static int sel_make_bools(void)
1002 {
1003 	int i, ret = 0;
1004 	ssize_t len;
1005 	struct dentry *dentry = NULL;
1006 	struct dentry *dir = bool_dir;
1007 	struct inode *inode = NULL;
1008 	struct inode_security_struct *isec;
1009 	char **names = NULL, *page;
1010 	int num;
1011 	int *values = NULL;
1012 	u32 sid;
1013 
1014 	/* remove any existing files */
1015 	kfree(bool_pending_values);
1016 	bool_pending_values = NULL;
1017 
1018 	sel_remove_entries(dir);
1019 
1020 	if (!(page = (char*)get_zeroed_page(GFP_KERNEL)))
1021 		return -ENOMEM;
1022 
1023 	ret = security_get_bools(&num, &names, &values);
1024 	if (ret != 0)
1025 		goto out;
1026 
1027 	for (i = 0; i < num; i++) {
1028 		dentry = d_alloc_name(dir, names[i]);
1029 		if (!dentry) {
1030 			ret = -ENOMEM;
1031 			goto err;
1032 		}
1033 		inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1034 		if (!inode) {
1035 			ret = -ENOMEM;
1036 			goto err;
1037 		}
1038 
1039 		len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1040 		if (len < 0) {
1041 			ret = -EINVAL;
1042 			goto err;
1043 		} else if (len >= PAGE_SIZE) {
1044 			ret = -ENAMETOOLONG;
1045 			goto err;
1046 		}
1047 		isec = (struct inode_security_struct*)inode->i_security;
1048 		if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid)))
1049 			goto err;
1050 		isec->sid = sid;
1051 		isec->initialized = 1;
1052 		inode->i_fop = &sel_bool_ops;
1053 		inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1054 		d_add(dentry, inode);
1055 	}
1056 	bool_num = num;
1057 	bool_pending_values = values;
1058 out:
1059 	free_page((unsigned long)page);
1060 	if (names) {
1061 		for (i = 0; i < num; i++)
1062 			kfree(names[i]);
1063 		kfree(names);
1064 	}
1065 	return ret;
1066 err:
1067 	kfree(values);
1068 	sel_remove_entries(dir);
1069 	ret = -ENOMEM;
1070 	goto out;
1071 }
1072 
1073 #define NULL_FILE_NAME "null"
1074 
1075 struct dentry *selinux_null = NULL;
1076 
1077 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1078 					    size_t count, loff_t *ppos)
1079 {
1080 	char tmpbuf[TMPBUFLEN];
1081 	ssize_t length;
1082 
1083 	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1084 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1085 }
1086 
1087 static ssize_t sel_write_avc_cache_threshold(struct file * file,
1088 					     const char __user * buf,
1089 					     size_t count, loff_t *ppos)
1090 
1091 {
1092 	char *page;
1093 	ssize_t ret;
1094 	int new_value;
1095 
1096 	if (count >= PAGE_SIZE) {
1097 		ret = -ENOMEM;
1098 		goto out;
1099 	}
1100 
1101 	if (*ppos != 0) {
1102 		/* No partial writes. */
1103 		ret = -EINVAL;
1104 		goto out;
1105 	}
1106 
1107 	page = (char*)get_zeroed_page(GFP_KERNEL);
1108 	if (!page) {
1109 		ret = -ENOMEM;
1110 		goto out;
1111 	}
1112 
1113 	if (copy_from_user(page, buf, count)) {
1114 		ret = -EFAULT;
1115 		goto out_free;
1116 	}
1117 
1118 	if (sscanf(page, "%u", &new_value) != 1) {
1119 		ret = -EINVAL;
1120 		goto out;
1121 	}
1122 
1123 	if (new_value != avc_cache_threshold) {
1124 		ret = task_has_security(current, SECURITY__SETSECPARAM);
1125 		if (ret)
1126 			goto out_free;
1127 		avc_cache_threshold = new_value;
1128 	}
1129 	ret = count;
1130 out_free:
1131 	free_page((unsigned long)page);
1132 out:
1133 	return ret;
1134 }
1135 
1136 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1137 				       size_t count, loff_t *ppos)
1138 {
1139 	char *page;
1140 	ssize_t ret = 0;
1141 
1142 	page = (char *)__get_free_page(GFP_KERNEL);
1143 	if (!page) {
1144 		ret = -ENOMEM;
1145 		goto out;
1146 	}
1147 	ret = avc_get_hash_stats(page);
1148 	if (ret >= 0)
1149 		ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1150 	free_page((unsigned long)page);
1151 out:
1152 	return ret;
1153 }
1154 
1155 static const struct file_operations sel_avc_cache_threshold_ops = {
1156 	.read		= sel_read_avc_cache_threshold,
1157 	.write		= sel_write_avc_cache_threshold,
1158 };
1159 
1160 static const struct file_operations sel_avc_hash_stats_ops = {
1161 	.read		= sel_read_avc_hash_stats,
1162 };
1163 
1164 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1165 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1166 {
1167 	int cpu;
1168 
1169 	for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1170 		if (!cpu_possible(cpu))
1171 			continue;
1172 		*idx = cpu + 1;
1173 		return &per_cpu(avc_cache_stats, cpu);
1174 	}
1175 	return NULL;
1176 }
1177 
1178 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1179 {
1180 	loff_t n = *pos - 1;
1181 
1182 	if (*pos == 0)
1183 		return SEQ_START_TOKEN;
1184 
1185 	return sel_avc_get_stat_idx(&n);
1186 }
1187 
1188 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1189 {
1190 	return sel_avc_get_stat_idx(pos);
1191 }
1192 
1193 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1194 {
1195 	struct avc_cache_stats *st = v;
1196 
1197 	if (v == SEQ_START_TOKEN)
1198 		seq_printf(seq, "lookups hits misses allocations reclaims "
1199 			   "frees\n");
1200 	else
1201 		seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1202 			   st->hits, st->misses, st->allocations,
1203 			   st->reclaims, st->frees);
1204 	return 0;
1205 }
1206 
1207 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1208 { }
1209 
1210 static struct seq_operations sel_avc_cache_stats_seq_ops = {
1211 	.start		= sel_avc_stats_seq_start,
1212 	.next		= sel_avc_stats_seq_next,
1213 	.show		= sel_avc_stats_seq_show,
1214 	.stop		= sel_avc_stats_seq_stop,
1215 };
1216 
1217 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1218 {
1219 	return seq_open(file, &sel_avc_cache_stats_seq_ops);
1220 }
1221 
1222 static const struct file_operations sel_avc_cache_stats_ops = {
1223 	.open		= sel_open_avc_cache_stats,
1224 	.read		= seq_read,
1225 	.llseek		= seq_lseek,
1226 	.release	= seq_release,
1227 };
1228 #endif
1229 
1230 static int sel_make_avc_files(struct dentry *dir)
1231 {
1232 	int i, ret = 0;
1233 	static struct tree_descr files[] = {
1234 		{ "cache_threshold",
1235 		  &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1236 		{ "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1237 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1238 		{ "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1239 #endif
1240 	};
1241 
1242 	for (i = 0; i < ARRAY_SIZE(files); i++) {
1243 		struct inode *inode;
1244 		struct dentry *dentry;
1245 
1246 		dentry = d_alloc_name(dir, files[i].name);
1247 		if (!dentry) {
1248 			ret = -ENOMEM;
1249 			goto out;
1250 		}
1251 
1252 		inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1253 		if (!inode) {
1254 			ret = -ENOMEM;
1255 			goto out;
1256 		}
1257 		inode->i_fop = files[i].ops;
1258 		inode->i_ino = ++sel_last_ino;
1259 		d_add(dentry, inode);
1260 	}
1261 out:
1262 	return ret;
1263 }
1264 
1265 static ssize_t sel_read_initcon(struct file * file, char __user *buf,
1266 				size_t count, loff_t *ppos)
1267 {
1268 	struct inode *inode;
1269 	char *con;
1270 	u32 sid, len;
1271 	ssize_t ret;
1272 
1273 	inode = file->f_path.dentry->d_inode;
1274 	sid = inode->i_ino&SEL_INO_MASK;
1275 	ret = security_sid_to_context(sid, &con, &len);
1276 	if (ret < 0)
1277 		return ret;
1278 
1279 	ret = simple_read_from_buffer(buf, count, ppos, con, len);
1280 	kfree(con);
1281 	return ret;
1282 }
1283 
1284 static const struct file_operations sel_initcon_ops = {
1285 	.read		= sel_read_initcon,
1286 };
1287 
1288 static int sel_make_initcon_files(struct dentry *dir)
1289 {
1290 	int i, ret = 0;
1291 
1292 	for (i = 1; i <= SECINITSID_NUM; i++) {
1293 		struct inode *inode;
1294 		struct dentry *dentry;
1295 		dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1296 		if (!dentry) {
1297 			ret = -ENOMEM;
1298 			goto out;
1299 		}
1300 
1301 		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1302 		if (!inode) {
1303 			ret = -ENOMEM;
1304 			goto out;
1305 		}
1306 		inode->i_fop = &sel_initcon_ops;
1307 		inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1308 		d_add(dentry, inode);
1309 	}
1310 out:
1311 	return ret;
1312 }
1313 
1314 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1315 {
1316 	return a / b - (a % b < 0);
1317 }
1318 
1319 static inline unsigned long sel_class_to_ino(u16 class)
1320 {
1321 	return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1322 }
1323 
1324 static inline u16 sel_ino_to_class(unsigned long ino)
1325 {
1326 	return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1327 }
1328 
1329 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1330 {
1331 	return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1332 }
1333 
1334 static inline u32 sel_ino_to_perm(unsigned long ino)
1335 {
1336 	return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1337 }
1338 
1339 static ssize_t sel_read_class(struct file * file, char __user *buf,
1340 				size_t count, loff_t *ppos)
1341 {
1342 	ssize_t rc, len;
1343 	char *page;
1344 	unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1345 
1346 	page = (char *)__get_free_page(GFP_KERNEL);
1347 	if (!page) {
1348 		rc = -ENOMEM;
1349 		goto out;
1350 	}
1351 
1352 	len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1353 	rc = simple_read_from_buffer(buf, count, ppos, page, len);
1354 	free_page((unsigned long)page);
1355 out:
1356 	return rc;
1357 }
1358 
1359 static const struct file_operations sel_class_ops = {
1360 	.read		= sel_read_class,
1361 };
1362 
1363 static ssize_t sel_read_perm(struct file * file, char __user *buf,
1364 				size_t count, loff_t *ppos)
1365 {
1366 	ssize_t rc, len;
1367 	char *page;
1368 	unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1369 
1370 	page = (char *)__get_free_page(GFP_KERNEL);
1371 	if (!page) {
1372 		rc = -ENOMEM;
1373 		goto out;
1374 	}
1375 
1376 	len = snprintf(page, PAGE_SIZE,"%d", sel_ino_to_perm(ino));
1377 	rc = simple_read_from_buffer(buf, count, ppos, page, len);
1378 	free_page((unsigned long)page);
1379 out:
1380 	return rc;
1381 }
1382 
1383 static const struct file_operations sel_perm_ops = {
1384 	.read		= sel_read_perm,
1385 };
1386 
1387 static int sel_make_perm_files(char *objclass, int classvalue,
1388 				struct dentry *dir)
1389 {
1390 	int i, rc = 0, nperms;
1391 	char **perms;
1392 
1393 	rc = security_get_permissions(objclass, &perms, &nperms);
1394 	if (rc)
1395 		goto out;
1396 
1397 	for (i = 0; i < nperms; i++) {
1398 		struct inode *inode;
1399 		struct dentry *dentry;
1400 
1401 		dentry = d_alloc_name(dir, perms[i]);
1402 		if (!dentry) {
1403 			rc = -ENOMEM;
1404 			goto out1;
1405 		}
1406 
1407 		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1408 		if (!inode) {
1409 			rc = -ENOMEM;
1410 			goto out1;
1411 		}
1412 		inode->i_fop = &sel_perm_ops;
1413 		/* i+1 since perm values are 1-indexed */
1414 		inode->i_ino = sel_perm_to_ino(classvalue, i+1);
1415 		d_add(dentry, inode);
1416 	}
1417 
1418 out1:
1419 	for (i = 0; i < nperms; i++)
1420 		kfree(perms[i]);
1421 	kfree(perms);
1422 out:
1423 	return rc;
1424 }
1425 
1426 static int sel_make_class_dir_entries(char *classname, int index,
1427 					struct dentry *dir)
1428 {
1429 	struct dentry *dentry = NULL;
1430 	struct inode *inode = NULL;
1431 	int rc;
1432 
1433 	dentry = d_alloc_name(dir, "index");
1434 	if (!dentry) {
1435 		rc = -ENOMEM;
1436 		goto out;
1437 	}
1438 
1439 	inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1440 	if (!inode) {
1441 		rc = -ENOMEM;
1442 		goto out;
1443 	}
1444 
1445 	inode->i_fop = &sel_class_ops;
1446 	inode->i_ino = sel_class_to_ino(index);
1447 	d_add(dentry, inode);
1448 
1449 	dentry = d_alloc_name(dir, "perms");
1450 	if (!dentry) {
1451 		rc = -ENOMEM;
1452 		goto out;
1453 	}
1454 
1455 	rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1456 	if (rc)
1457 		goto out;
1458 
1459 	rc = sel_make_perm_files(classname, index, dentry);
1460 
1461 out:
1462 	return rc;
1463 }
1464 
1465 static void sel_remove_classes(void)
1466 {
1467 	struct list_head *class_node;
1468 
1469 	list_for_each(class_node, &class_dir->d_subdirs) {
1470 		struct dentry *class_subdir = list_entry(class_node,
1471 					struct dentry, d_u.d_child);
1472 		struct list_head *class_subdir_node;
1473 
1474 		list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1475 			struct dentry *d = list_entry(class_subdir_node,
1476 						struct dentry, d_u.d_child);
1477 
1478 			if (d->d_inode)
1479 				if (d->d_inode->i_mode & S_IFDIR)
1480 					sel_remove_entries(d);
1481 		}
1482 
1483 		sel_remove_entries(class_subdir);
1484 	}
1485 
1486 	sel_remove_entries(class_dir);
1487 }
1488 
1489 static int sel_make_classes(void)
1490 {
1491 	int rc = 0, nclasses, i;
1492 	char **classes;
1493 
1494 	/* delete any existing entries */
1495 	sel_remove_classes();
1496 
1497 	rc = security_get_classes(&classes, &nclasses);
1498 	if (rc < 0)
1499 		goto out;
1500 
1501 	/* +2 since classes are 1-indexed */
1502 	last_class_ino = sel_class_to_ino(nclasses+2);
1503 
1504 	for (i = 0; i < nclasses; i++) {
1505 		struct dentry *class_name_dir;
1506 
1507 		class_name_dir = d_alloc_name(class_dir, classes[i]);
1508 		if (!class_name_dir) {
1509 			rc = -ENOMEM;
1510 			goto out1;
1511 		}
1512 
1513 		rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1514 				&last_class_ino);
1515 		if (rc)
1516 			goto out1;
1517 
1518 		/* i+1 since class values are 1-indexed */
1519 		rc = sel_make_class_dir_entries(classes[i], i+1,
1520 				class_name_dir);
1521 		if (rc)
1522 			goto out1;
1523 	}
1524 
1525 out1:
1526 	for (i = 0; i < nclasses; i++)
1527 		kfree(classes[i]);
1528 	kfree(classes);
1529 out:
1530 	return rc;
1531 }
1532 
1533 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1534 			unsigned long *ino)
1535 {
1536 	int ret = 0;
1537 	struct inode *inode;
1538 
1539 	inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1540 	if (!inode) {
1541 		ret = -ENOMEM;
1542 		goto out;
1543 	}
1544 	inode->i_op = &simple_dir_inode_operations;
1545 	inode->i_fop = &simple_dir_operations;
1546 	inode->i_ino = ++(*ino);
1547 	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1548 	inc_nlink(inode);
1549 	d_add(dentry, inode);
1550 	/* bump link count on parent directory, too */
1551 	inc_nlink(dir);
1552 out:
1553 	return ret;
1554 }
1555 
1556 static int sel_fill_super(struct super_block * sb, void * data, int silent)
1557 {
1558 	int ret;
1559 	struct dentry *dentry;
1560 	struct inode *inode, *root_inode;
1561 	struct inode_security_struct *isec;
1562 
1563 	static struct tree_descr selinux_files[] = {
1564 		[SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1565 		[SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1566 		[SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1567 		[SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1568 		[SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1569 		[SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1570 		[SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1571 		[SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1572 		[SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1573 		[SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1574 		[SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1575 		[SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1576 		[SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1577 		[SEL_COMPAT_NET] = {"compat_net", &sel_compat_net_ops, S_IRUGO|S_IWUSR},
1578 		/* last one */ {""}
1579 	};
1580 	ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1581 	if (ret)
1582 		goto err;
1583 
1584 	root_inode = sb->s_root->d_inode;
1585 
1586 	dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1587 	if (!dentry) {
1588 		ret = -ENOMEM;
1589 		goto err;
1590 	}
1591 
1592 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1593 	if (ret)
1594 		goto err;
1595 
1596 	bool_dir = dentry;
1597 
1598 	dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1599 	if (!dentry) {
1600 		ret = -ENOMEM;
1601 		goto err;
1602 	}
1603 
1604 	inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1605 	if (!inode) {
1606 		ret = -ENOMEM;
1607 		goto err;
1608 	}
1609 	inode->i_ino = ++sel_last_ino;
1610 	isec = (struct inode_security_struct*)inode->i_security;
1611 	isec->sid = SECINITSID_DEVNULL;
1612 	isec->sclass = SECCLASS_CHR_FILE;
1613 	isec->initialized = 1;
1614 
1615 	init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1616 	d_add(dentry, inode);
1617 	selinux_null = dentry;
1618 
1619 	dentry = d_alloc_name(sb->s_root, "avc");
1620 	if (!dentry) {
1621 		ret = -ENOMEM;
1622 		goto err;
1623 	}
1624 
1625 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1626 	if (ret)
1627 		goto err;
1628 
1629 	ret = sel_make_avc_files(dentry);
1630 	if (ret)
1631 		goto err;
1632 
1633 	dentry = d_alloc_name(sb->s_root, "initial_contexts");
1634 	if (!dentry) {
1635 		ret = -ENOMEM;
1636 		goto err;
1637 	}
1638 
1639 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1640 	if (ret)
1641 		goto err;
1642 
1643 	ret = sel_make_initcon_files(dentry);
1644 	if (ret)
1645 		goto err;
1646 
1647 	dentry = d_alloc_name(sb->s_root, "class");
1648 	if (!dentry) {
1649 		ret = -ENOMEM;
1650 		goto err;
1651 	}
1652 
1653 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1654 	if (ret)
1655 		goto err;
1656 
1657 	class_dir = dentry;
1658 
1659 out:
1660 	return ret;
1661 err:
1662 	printk(KERN_ERR "%s:  failed while creating inodes\n", __FUNCTION__);
1663 	goto out;
1664 }
1665 
1666 static int sel_get_sb(struct file_system_type *fs_type,
1667 		      int flags, const char *dev_name, void *data,
1668 		      struct vfsmount *mnt)
1669 {
1670 	return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
1671 }
1672 
1673 static struct file_system_type sel_fs_type = {
1674 	.name		= "selinuxfs",
1675 	.get_sb		= sel_get_sb,
1676 	.kill_sb	= kill_litter_super,
1677 };
1678 
1679 struct vfsmount *selinuxfs_mount;
1680 
1681 static int __init init_sel_fs(void)
1682 {
1683 	int err;
1684 
1685 	if (!selinux_enabled)
1686 		return 0;
1687 	err = register_filesystem(&sel_fs_type);
1688 	if (!err) {
1689 		selinuxfs_mount = kern_mount(&sel_fs_type);
1690 		if (IS_ERR(selinuxfs_mount)) {
1691 			printk(KERN_ERR "selinuxfs:  could not mount!\n");
1692 			err = PTR_ERR(selinuxfs_mount);
1693 			selinuxfs_mount = NULL;
1694 		}
1695 	}
1696 	return err;
1697 }
1698 
1699 __initcall(init_sel_fs);
1700 
1701 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1702 void exit_sel_fs(void)
1703 {
1704 	unregister_filesystem(&sel_fs_type);
1705 }
1706 #endif
1707