xref: /openbmc/linux/security/selinux/selinuxfs.c (revision 277d342f)
1 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
2  *
3  *	Added conditional policy language extensions
4  *
5  *  Updated: Hewlett-Packard <paul.moore@hp.com>
6  *
7  *	Added support for the policy capability bitmap
8  *
9  * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
10  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
11  * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
12  *	This program is free software; you can redistribute it and/or modify
13  *	it under the terms of the GNU General Public License as published by
14  *	the Free Software Foundation, version 2.
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/pagemap.h>
19 #include <linux/slab.h>
20 #include <linux/vmalloc.h>
21 #include <linux/fs.h>
22 #include <linux/mutex.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/security.h>
26 #include <linux/major.h>
27 #include <linux/seq_file.h>
28 #include <linux/percpu.h>
29 #include <linux/audit.h>
30 #include <linux/uaccess.h>
31 
32 /* selinuxfs pseudo filesystem for exporting the security policy API.
33    Based on the proc code and the fs/nfsd/nfsctl.c code. */
34 
35 #include "flask.h"
36 #include "avc.h"
37 #include "avc_ss.h"
38 #include "security.h"
39 #include "objsec.h"
40 #include "conditional.h"
41 
42 /* Policy capability filenames */
43 static char *policycap_names[] = {
44 	"network_peer_controls",
45 	"open_perms"
46 };
47 
48 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
49 
50 int selinux_compat_net = 0;
51 
52 static int __init checkreqprot_setup(char *str)
53 {
54 	unsigned long checkreqprot;
55 	if (!strict_strtoul(str, 0, &checkreqprot))
56 		selinux_checkreqprot = checkreqprot ? 1 : 0;
57 	return 1;
58 }
59 __setup("checkreqprot=", checkreqprot_setup);
60 
61 static int __init selinux_compat_net_setup(char *str)
62 {
63 	unsigned long compat_net;
64 	if (!strict_strtoul(str, 0, &compat_net))
65 		selinux_compat_net = compat_net ? 1 : 0;
66 	return 1;
67 }
68 __setup("selinux_compat_net=", selinux_compat_net_setup);
69 
70 
71 static DEFINE_MUTEX(sel_mutex);
72 
73 /* global data for booleans */
74 static struct dentry *bool_dir;
75 static int bool_num;
76 static char **bool_pending_names;
77 static int *bool_pending_values;
78 
79 /* global data for classes */
80 static struct dentry *class_dir;
81 static unsigned long last_class_ino;
82 
83 /* global data for policy capabilities */
84 static struct dentry *policycap_dir;
85 
86 extern void selnl_notify_setenforce(int val);
87 
88 /* Check whether a task is allowed to use a security operation. */
89 static int task_has_security(struct task_struct *tsk,
90 			     u32 perms)
91 {
92 	const struct task_security_struct *tsec;
93 	u32 sid = 0;
94 
95 	rcu_read_lock();
96 	tsec = __task_cred(tsk)->security;
97 	if (tsec)
98 		sid = tsec->sid;
99 	rcu_read_unlock();
100 	if (!tsec)
101 		return -EACCES;
102 
103 	return avc_has_perm(sid, SECINITSID_SECURITY,
104 			    SECCLASS_SECURITY, perms, NULL);
105 }
106 
107 enum sel_inos {
108 	SEL_ROOT_INO = 2,
109 	SEL_LOAD,	/* load policy */
110 	SEL_ENFORCE,	/* get or set enforcing status */
111 	SEL_CONTEXT,	/* validate context */
112 	SEL_ACCESS,	/* compute access decision */
113 	SEL_CREATE,	/* compute create labeling decision */
114 	SEL_RELABEL,	/* compute relabeling decision */
115 	SEL_USER,	/* compute reachable user contexts */
116 	SEL_POLICYVERS,	/* return policy version for this kernel */
117 	SEL_COMMIT_BOOLS, /* commit new boolean values */
118 	SEL_MLS,	/* return if MLS policy is enabled */
119 	SEL_DISABLE,	/* disable SELinux until next reboot */
120 	SEL_MEMBER,	/* compute polyinstantiation membership decision */
121 	SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
122 	SEL_COMPAT_NET,	/* whether to use old compat network packet controls */
123 	SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
124 	SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
125 	SEL_INO_NEXT,	/* The next inode number to use */
126 };
127 
128 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
129 
130 #define SEL_INITCON_INO_OFFSET		0x01000000
131 #define SEL_BOOL_INO_OFFSET		0x02000000
132 #define SEL_CLASS_INO_OFFSET		0x04000000
133 #define SEL_POLICYCAP_INO_OFFSET	0x08000000
134 #define SEL_INO_MASK			0x00ffffff
135 
136 #define TMPBUFLEN	12
137 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
138 				size_t count, loff_t *ppos)
139 {
140 	char tmpbuf[TMPBUFLEN];
141 	ssize_t length;
142 
143 	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
144 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
145 }
146 
147 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
148 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
149 				 size_t count, loff_t *ppos)
150 
151 {
152 	char *page;
153 	ssize_t length;
154 	int new_value;
155 
156 	if (count >= PAGE_SIZE)
157 		return -ENOMEM;
158 	if (*ppos != 0) {
159 		/* No partial writes. */
160 		return -EINVAL;
161 	}
162 	page = (char *)get_zeroed_page(GFP_KERNEL);
163 	if (!page)
164 		return -ENOMEM;
165 	length = -EFAULT;
166 	if (copy_from_user(page, buf, count))
167 		goto out;
168 
169 	length = -EINVAL;
170 	if (sscanf(page, "%d", &new_value) != 1)
171 		goto out;
172 
173 	if (new_value != selinux_enforcing) {
174 		length = task_has_security(current, SECURITY__SETENFORCE);
175 		if (length)
176 			goto out;
177 		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
178 			"enforcing=%d old_enforcing=%d auid=%u ses=%u",
179 			new_value, selinux_enforcing,
180 			audit_get_loginuid(current),
181 			audit_get_sessionid(current));
182 		selinux_enforcing = new_value;
183 		if (selinux_enforcing)
184 			avc_ss_reset(0);
185 		selnl_notify_setenforce(selinux_enforcing);
186 	}
187 	length = count;
188 out:
189 	free_page((unsigned long) page);
190 	return length;
191 }
192 #else
193 #define sel_write_enforce NULL
194 #endif
195 
196 static const struct file_operations sel_enforce_ops = {
197 	.read		= sel_read_enforce,
198 	.write		= sel_write_enforce,
199 };
200 
201 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
202 					size_t count, loff_t *ppos)
203 {
204 	char tmpbuf[TMPBUFLEN];
205 	ssize_t length;
206 	ino_t ino = filp->f_path.dentry->d_inode->i_ino;
207 	int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
208 		security_get_reject_unknown() : !security_get_allow_unknown();
209 
210 	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
211 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
212 }
213 
214 static const struct file_operations sel_handle_unknown_ops = {
215 	.read		= sel_read_handle_unknown,
216 };
217 
218 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
219 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
220 				 size_t count, loff_t *ppos)
221 
222 {
223 	char *page;
224 	ssize_t length;
225 	int new_value;
226 	extern int selinux_disable(void);
227 
228 	if (count >= PAGE_SIZE)
229 		return -ENOMEM;
230 	if (*ppos != 0) {
231 		/* No partial writes. */
232 		return -EINVAL;
233 	}
234 	page = (char *)get_zeroed_page(GFP_KERNEL);
235 	if (!page)
236 		return -ENOMEM;
237 	length = -EFAULT;
238 	if (copy_from_user(page, buf, count))
239 		goto out;
240 
241 	length = -EINVAL;
242 	if (sscanf(page, "%d", &new_value) != 1)
243 		goto out;
244 
245 	if (new_value) {
246 		length = selinux_disable();
247 		if (length < 0)
248 			goto out;
249 		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
250 			"selinux=0 auid=%u ses=%u",
251 			audit_get_loginuid(current),
252 			audit_get_sessionid(current));
253 	}
254 
255 	length = count;
256 out:
257 	free_page((unsigned long) page);
258 	return length;
259 }
260 #else
261 #define sel_write_disable NULL
262 #endif
263 
264 static const struct file_operations sel_disable_ops = {
265 	.write		= sel_write_disable,
266 };
267 
268 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
269 				   size_t count, loff_t *ppos)
270 {
271 	char tmpbuf[TMPBUFLEN];
272 	ssize_t length;
273 
274 	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
275 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
276 }
277 
278 static const struct file_operations sel_policyvers_ops = {
279 	.read		= sel_read_policyvers,
280 };
281 
282 /* declaration for sel_write_load */
283 static int sel_make_bools(void);
284 static int sel_make_classes(void);
285 static int sel_make_policycap(void);
286 
287 /* declaration for sel_make_class_dirs */
288 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
289 			unsigned long *ino);
290 
291 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
292 				size_t count, loff_t *ppos)
293 {
294 	char tmpbuf[TMPBUFLEN];
295 	ssize_t length;
296 
297 	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
298 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
299 }
300 
301 static const struct file_operations sel_mls_ops = {
302 	.read		= sel_read_mls,
303 };
304 
305 static ssize_t sel_write_load(struct file *file, const char __user *buf,
306 			      size_t count, loff_t *ppos)
307 
308 {
309 	int ret;
310 	ssize_t length;
311 	void *data = NULL;
312 
313 	mutex_lock(&sel_mutex);
314 
315 	length = task_has_security(current, SECURITY__LOAD_POLICY);
316 	if (length)
317 		goto out;
318 
319 	if (*ppos != 0) {
320 		/* No partial writes. */
321 		length = -EINVAL;
322 		goto out;
323 	}
324 
325 	if ((count > 64 * 1024 * 1024)
326 	    || (data = vmalloc(count)) == NULL) {
327 		length = -ENOMEM;
328 		goto out;
329 	}
330 
331 	length = -EFAULT;
332 	if (copy_from_user(data, buf, count) != 0)
333 		goto out;
334 
335 	length = security_load_policy(data, count);
336 	if (length)
337 		goto out;
338 
339 	ret = sel_make_bools();
340 	if (ret) {
341 		length = ret;
342 		goto out1;
343 	}
344 
345 	ret = sel_make_classes();
346 	if (ret) {
347 		length = ret;
348 		goto out1;
349 	}
350 
351 	ret = sel_make_policycap();
352 	if (ret)
353 		length = ret;
354 	else
355 		length = count;
356 
357 out1:
358 	audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
359 		"policy loaded auid=%u ses=%u",
360 		audit_get_loginuid(current),
361 		audit_get_sessionid(current));
362 out:
363 	mutex_unlock(&sel_mutex);
364 	vfree(data);
365 	return length;
366 }
367 
368 static const struct file_operations sel_load_ops = {
369 	.write		= sel_write_load,
370 };
371 
372 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
373 {
374 	char *canon;
375 	u32 sid, len;
376 	ssize_t length;
377 
378 	length = task_has_security(current, SECURITY__CHECK_CONTEXT);
379 	if (length)
380 		return length;
381 
382 	length = security_context_to_sid(buf, size, &sid);
383 	if (length < 0)
384 		return length;
385 
386 	length = security_sid_to_context(sid, &canon, &len);
387 	if (length < 0)
388 		return length;
389 
390 	if (len > SIMPLE_TRANSACTION_LIMIT) {
391 		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
392 			"payload max\n", __func__, len);
393 		length = -ERANGE;
394 		goto out;
395 	}
396 
397 	memcpy(buf, canon, len);
398 	length = len;
399 out:
400 	kfree(canon);
401 	return length;
402 }
403 
404 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
405 				     size_t count, loff_t *ppos)
406 {
407 	char tmpbuf[TMPBUFLEN];
408 	ssize_t length;
409 
410 	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
411 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
412 }
413 
414 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
415 				      size_t count, loff_t *ppos)
416 {
417 	char *page;
418 	ssize_t length;
419 	unsigned int new_value;
420 
421 	length = task_has_security(current, SECURITY__SETCHECKREQPROT);
422 	if (length)
423 		return length;
424 
425 	if (count >= PAGE_SIZE)
426 		return -ENOMEM;
427 	if (*ppos != 0) {
428 		/* No partial writes. */
429 		return -EINVAL;
430 	}
431 	page = (char *)get_zeroed_page(GFP_KERNEL);
432 	if (!page)
433 		return -ENOMEM;
434 	length = -EFAULT;
435 	if (copy_from_user(page, buf, count))
436 		goto out;
437 
438 	length = -EINVAL;
439 	if (sscanf(page, "%u", &new_value) != 1)
440 		goto out;
441 
442 	selinux_checkreqprot = new_value ? 1 : 0;
443 	length = count;
444 out:
445 	free_page((unsigned long) page);
446 	return length;
447 }
448 static const struct file_operations sel_checkreqprot_ops = {
449 	.read		= sel_read_checkreqprot,
450 	.write		= sel_write_checkreqprot,
451 };
452 
453 static ssize_t sel_read_compat_net(struct file *filp, char __user *buf,
454 				   size_t count, loff_t *ppos)
455 {
456 	char tmpbuf[TMPBUFLEN];
457 	ssize_t length;
458 
459 	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_compat_net);
460 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
461 }
462 
463 static ssize_t sel_write_compat_net(struct file *file, const char __user *buf,
464 				    size_t count, loff_t *ppos)
465 {
466 	char *page;
467 	ssize_t length;
468 	int new_value;
469 
470 	length = task_has_security(current, SECURITY__LOAD_POLICY);
471 	if (length)
472 		return length;
473 
474 	if (count >= PAGE_SIZE)
475 		return -ENOMEM;
476 	if (*ppos != 0) {
477 		/* No partial writes. */
478 		return -EINVAL;
479 	}
480 	page = (char *)get_zeroed_page(GFP_KERNEL);
481 	if (!page)
482 		return -ENOMEM;
483 	length = -EFAULT;
484 	if (copy_from_user(page, buf, count))
485 		goto out;
486 
487 	length = -EINVAL;
488 	if (sscanf(page, "%d", &new_value) != 1)
489 		goto out;
490 
491 	if (new_value) {
492 		printk(KERN_NOTICE
493 		       "SELinux: compat_net is deprecated, please use secmark"
494 		       " instead\n");
495 		selinux_compat_net = 1;
496 	} else
497 		selinux_compat_net = 0;
498 	length = count;
499 out:
500 	free_page((unsigned long) page);
501 	return length;
502 }
503 static const struct file_operations sel_compat_net_ops = {
504 	.read		= sel_read_compat_net,
505 	.write		= sel_write_compat_net,
506 };
507 
508 /*
509  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
510  */
511 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
512 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
513 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
514 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
515 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
516 
517 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
518 	[SEL_ACCESS] = sel_write_access,
519 	[SEL_CREATE] = sel_write_create,
520 	[SEL_RELABEL] = sel_write_relabel,
521 	[SEL_USER] = sel_write_user,
522 	[SEL_MEMBER] = sel_write_member,
523 	[SEL_CONTEXT] = sel_write_context,
524 };
525 
526 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
527 {
528 	ino_t ino = file->f_path.dentry->d_inode->i_ino;
529 	char *data;
530 	ssize_t rv;
531 
532 	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
533 		return -EINVAL;
534 
535 	data = simple_transaction_get(file, buf, size);
536 	if (IS_ERR(data))
537 		return PTR_ERR(data);
538 
539 	rv = write_op[ino](file, data, size);
540 	if (rv > 0) {
541 		simple_transaction_set(file, rv);
542 		rv = size;
543 	}
544 	return rv;
545 }
546 
547 static const struct file_operations transaction_ops = {
548 	.write		= selinux_transaction_write,
549 	.read		= simple_transaction_read,
550 	.release	= simple_transaction_release,
551 };
552 
553 /*
554  * payload - write methods
555  * If the method has a response, the response should be put in buf,
556  * and the length returned.  Otherwise return 0 or and -error.
557  */
558 
559 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
560 {
561 	char *scon, *tcon;
562 	u32 ssid, tsid;
563 	u16 tclass;
564 	u32 req;
565 	struct av_decision avd;
566 	ssize_t length;
567 
568 	length = task_has_security(current, SECURITY__COMPUTE_AV);
569 	if (length)
570 		return length;
571 
572 	length = -ENOMEM;
573 	scon = kzalloc(size+1, GFP_KERNEL);
574 	if (!scon)
575 		return length;
576 
577 	tcon = kzalloc(size+1, GFP_KERNEL);
578 	if (!tcon)
579 		goto out;
580 
581 	length = -EINVAL;
582 	if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
583 		goto out2;
584 
585 	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
586 	if (length < 0)
587 		goto out2;
588 	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
589 	if (length < 0)
590 		goto out2;
591 
592 	length = security_compute_av(ssid, tsid, tclass, req, &avd);
593 	if (length < 0)
594 		goto out2;
595 
596 	length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
597 			  "%x %x %x %x %u",
598 			  avd.allowed, avd.decided,
599 			  avd.auditallow, avd.auditdeny,
600 			  avd.seqno);
601 out2:
602 	kfree(tcon);
603 out:
604 	kfree(scon);
605 	return length;
606 }
607 
608 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
609 {
610 	char *scon, *tcon;
611 	u32 ssid, tsid, newsid;
612 	u16 tclass;
613 	ssize_t length;
614 	char *newcon;
615 	u32 len;
616 
617 	length = task_has_security(current, SECURITY__COMPUTE_CREATE);
618 	if (length)
619 		return length;
620 
621 	length = -ENOMEM;
622 	scon = kzalloc(size+1, GFP_KERNEL);
623 	if (!scon)
624 		return length;
625 
626 	tcon = kzalloc(size+1, GFP_KERNEL);
627 	if (!tcon)
628 		goto out;
629 
630 	length = -EINVAL;
631 	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
632 		goto out2;
633 
634 	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
635 	if (length < 0)
636 		goto out2;
637 	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
638 	if (length < 0)
639 		goto out2;
640 
641 	length = security_transition_sid(ssid, tsid, tclass, &newsid);
642 	if (length < 0)
643 		goto out2;
644 
645 	length = security_sid_to_context(newsid, &newcon, &len);
646 	if (length < 0)
647 		goto out2;
648 
649 	if (len > SIMPLE_TRANSACTION_LIMIT) {
650 		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
651 			"payload max\n", __func__, len);
652 		length = -ERANGE;
653 		goto out3;
654 	}
655 
656 	memcpy(buf, newcon, len);
657 	length = len;
658 out3:
659 	kfree(newcon);
660 out2:
661 	kfree(tcon);
662 out:
663 	kfree(scon);
664 	return length;
665 }
666 
667 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
668 {
669 	char *scon, *tcon;
670 	u32 ssid, tsid, newsid;
671 	u16 tclass;
672 	ssize_t length;
673 	char *newcon;
674 	u32 len;
675 
676 	length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
677 	if (length)
678 		return length;
679 
680 	length = -ENOMEM;
681 	scon = kzalloc(size+1, GFP_KERNEL);
682 	if (!scon)
683 		return length;
684 
685 	tcon = kzalloc(size+1, GFP_KERNEL);
686 	if (!tcon)
687 		goto out;
688 
689 	length = -EINVAL;
690 	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
691 		goto out2;
692 
693 	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
694 	if (length < 0)
695 		goto out2;
696 	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
697 	if (length < 0)
698 		goto out2;
699 
700 	length = security_change_sid(ssid, tsid, tclass, &newsid);
701 	if (length < 0)
702 		goto out2;
703 
704 	length = security_sid_to_context(newsid, &newcon, &len);
705 	if (length < 0)
706 		goto out2;
707 
708 	if (len > SIMPLE_TRANSACTION_LIMIT) {
709 		length = -ERANGE;
710 		goto out3;
711 	}
712 
713 	memcpy(buf, newcon, len);
714 	length = len;
715 out3:
716 	kfree(newcon);
717 out2:
718 	kfree(tcon);
719 out:
720 	kfree(scon);
721 	return length;
722 }
723 
724 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
725 {
726 	char *con, *user, *ptr;
727 	u32 sid, *sids;
728 	ssize_t length;
729 	char *newcon;
730 	int i, rc;
731 	u32 len, nsids;
732 
733 	length = task_has_security(current, SECURITY__COMPUTE_USER);
734 	if (length)
735 		return length;
736 
737 	length = -ENOMEM;
738 	con = kzalloc(size+1, GFP_KERNEL);
739 	if (!con)
740 		return length;
741 
742 	user = kzalloc(size+1, GFP_KERNEL);
743 	if (!user)
744 		goto out;
745 
746 	length = -EINVAL;
747 	if (sscanf(buf, "%s %s", con, user) != 2)
748 		goto out2;
749 
750 	length = security_context_to_sid(con, strlen(con)+1, &sid);
751 	if (length < 0)
752 		goto out2;
753 
754 	length = security_get_user_sids(sid, user, &sids, &nsids);
755 	if (length < 0)
756 		goto out2;
757 
758 	length = sprintf(buf, "%u", nsids) + 1;
759 	ptr = buf + length;
760 	for (i = 0; i < nsids; i++) {
761 		rc = security_sid_to_context(sids[i], &newcon, &len);
762 		if (rc) {
763 			length = rc;
764 			goto out3;
765 		}
766 		if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
767 			kfree(newcon);
768 			length = -ERANGE;
769 			goto out3;
770 		}
771 		memcpy(ptr, newcon, len);
772 		kfree(newcon);
773 		ptr += len;
774 		length += len;
775 	}
776 out3:
777 	kfree(sids);
778 out2:
779 	kfree(user);
780 out:
781 	kfree(con);
782 	return length;
783 }
784 
785 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
786 {
787 	char *scon, *tcon;
788 	u32 ssid, tsid, newsid;
789 	u16 tclass;
790 	ssize_t length;
791 	char *newcon;
792 	u32 len;
793 
794 	length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
795 	if (length)
796 		return length;
797 
798 	length = -ENOMEM;
799 	scon = kzalloc(size+1, GFP_KERNEL);
800 	if (!scon)
801 		return length;
802 
803 	tcon = kzalloc(size+1, GFP_KERNEL);
804 	if (!tcon)
805 		goto out;
806 
807 	length = -EINVAL;
808 	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
809 		goto out2;
810 
811 	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
812 	if (length < 0)
813 		goto out2;
814 	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
815 	if (length < 0)
816 		goto out2;
817 
818 	length = security_member_sid(ssid, tsid, tclass, &newsid);
819 	if (length < 0)
820 		goto out2;
821 
822 	length = security_sid_to_context(newsid, &newcon, &len);
823 	if (length < 0)
824 		goto out2;
825 
826 	if (len > SIMPLE_TRANSACTION_LIMIT) {
827 		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
828 			"payload max\n", __func__, len);
829 		length = -ERANGE;
830 		goto out3;
831 	}
832 
833 	memcpy(buf, newcon, len);
834 	length = len;
835 out3:
836 	kfree(newcon);
837 out2:
838 	kfree(tcon);
839 out:
840 	kfree(scon);
841 	return length;
842 }
843 
844 static struct inode *sel_make_inode(struct super_block *sb, int mode)
845 {
846 	struct inode *ret = new_inode(sb);
847 
848 	if (ret) {
849 		ret->i_mode = mode;
850 		ret->i_uid = ret->i_gid = 0;
851 		ret->i_blocks = 0;
852 		ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
853 	}
854 	return ret;
855 }
856 
857 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
858 			     size_t count, loff_t *ppos)
859 {
860 	char *page = NULL;
861 	ssize_t length;
862 	ssize_t ret;
863 	int cur_enforcing;
864 	struct inode *inode = filep->f_path.dentry->d_inode;
865 	unsigned index = inode->i_ino & SEL_INO_MASK;
866 	const char *name = filep->f_path.dentry->d_name.name;
867 
868 	mutex_lock(&sel_mutex);
869 
870 	if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
871 		ret = -EINVAL;
872 		goto out;
873 	}
874 
875 	if (count > PAGE_SIZE) {
876 		ret = -EINVAL;
877 		goto out;
878 	}
879 	page = (char *)get_zeroed_page(GFP_KERNEL);
880 	if (!page) {
881 		ret = -ENOMEM;
882 		goto out;
883 	}
884 
885 	cur_enforcing = security_get_bool_value(index);
886 	if (cur_enforcing < 0) {
887 		ret = cur_enforcing;
888 		goto out;
889 	}
890 	length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
891 			  bool_pending_values[index]);
892 	ret = simple_read_from_buffer(buf, count, ppos, page, length);
893 out:
894 	mutex_unlock(&sel_mutex);
895 	if (page)
896 		free_page((unsigned long)page);
897 	return ret;
898 }
899 
900 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
901 			      size_t count, loff_t *ppos)
902 {
903 	char *page = NULL;
904 	ssize_t length;
905 	int new_value;
906 	struct inode *inode = filep->f_path.dentry->d_inode;
907 	unsigned index = inode->i_ino & SEL_INO_MASK;
908 	const char *name = filep->f_path.dentry->d_name.name;
909 
910 	mutex_lock(&sel_mutex);
911 
912 	length = task_has_security(current, SECURITY__SETBOOL);
913 	if (length)
914 		goto out;
915 
916 	if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
917 		length = -EINVAL;
918 		goto out;
919 	}
920 
921 	if (count >= PAGE_SIZE) {
922 		length = -ENOMEM;
923 		goto out;
924 	}
925 
926 	if (*ppos != 0) {
927 		/* No partial writes. */
928 		length = -EINVAL;
929 		goto out;
930 	}
931 	page = (char *)get_zeroed_page(GFP_KERNEL);
932 	if (!page) {
933 		length = -ENOMEM;
934 		goto out;
935 	}
936 
937 	length = -EFAULT;
938 	if (copy_from_user(page, buf, count))
939 		goto out;
940 
941 	length = -EINVAL;
942 	if (sscanf(page, "%d", &new_value) != 1)
943 		goto out;
944 
945 	if (new_value)
946 		new_value = 1;
947 
948 	bool_pending_values[index] = new_value;
949 	length = count;
950 
951 out:
952 	mutex_unlock(&sel_mutex);
953 	if (page)
954 		free_page((unsigned long) page);
955 	return length;
956 }
957 
958 static const struct file_operations sel_bool_ops = {
959 	.read		= sel_read_bool,
960 	.write		= sel_write_bool,
961 };
962 
963 static ssize_t sel_commit_bools_write(struct file *filep,
964 				      const char __user *buf,
965 				      size_t count, loff_t *ppos)
966 {
967 	char *page = NULL;
968 	ssize_t length;
969 	int new_value;
970 
971 	mutex_lock(&sel_mutex);
972 
973 	length = task_has_security(current, SECURITY__SETBOOL);
974 	if (length)
975 		goto out;
976 
977 	if (count >= PAGE_SIZE) {
978 		length = -ENOMEM;
979 		goto out;
980 	}
981 	if (*ppos != 0) {
982 		/* No partial writes. */
983 		goto out;
984 	}
985 	page = (char *)get_zeroed_page(GFP_KERNEL);
986 	if (!page) {
987 		length = -ENOMEM;
988 		goto out;
989 	}
990 
991 	length = -EFAULT;
992 	if (copy_from_user(page, buf, count))
993 		goto out;
994 
995 	length = -EINVAL;
996 	if (sscanf(page, "%d", &new_value) != 1)
997 		goto out;
998 
999 	if (new_value && bool_pending_values)
1000 		security_set_bools(bool_num, bool_pending_values);
1001 
1002 	length = count;
1003 
1004 out:
1005 	mutex_unlock(&sel_mutex);
1006 	if (page)
1007 		free_page((unsigned long) page);
1008 	return length;
1009 }
1010 
1011 static const struct file_operations sel_commit_bools_ops = {
1012 	.write		= sel_commit_bools_write,
1013 };
1014 
1015 static void sel_remove_entries(struct dentry *de)
1016 {
1017 	struct list_head *node;
1018 
1019 	spin_lock(&dcache_lock);
1020 	node = de->d_subdirs.next;
1021 	while (node != &de->d_subdirs) {
1022 		struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1023 		list_del_init(node);
1024 
1025 		if (d->d_inode) {
1026 			d = dget_locked(d);
1027 			spin_unlock(&dcache_lock);
1028 			d_delete(d);
1029 			simple_unlink(de->d_inode, d);
1030 			dput(d);
1031 			spin_lock(&dcache_lock);
1032 		}
1033 		node = de->d_subdirs.next;
1034 	}
1035 
1036 	spin_unlock(&dcache_lock);
1037 }
1038 
1039 #define BOOL_DIR_NAME "booleans"
1040 
1041 static int sel_make_bools(void)
1042 {
1043 	int i, ret = 0;
1044 	ssize_t len;
1045 	struct dentry *dentry = NULL;
1046 	struct dentry *dir = bool_dir;
1047 	struct inode *inode = NULL;
1048 	struct inode_security_struct *isec;
1049 	char **names = NULL, *page;
1050 	int num;
1051 	int *values = NULL;
1052 	u32 sid;
1053 
1054 	/* remove any existing files */
1055 	kfree(bool_pending_names);
1056 	kfree(bool_pending_values);
1057 	bool_pending_names = NULL;
1058 	bool_pending_values = NULL;
1059 
1060 	sel_remove_entries(dir);
1061 
1062 	page = (char *)get_zeroed_page(GFP_KERNEL);
1063 	if (!page)
1064 		return -ENOMEM;
1065 
1066 	ret = security_get_bools(&num, &names, &values);
1067 	if (ret != 0)
1068 		goto out;
1069 
1070 	for (i = 0; i < num; i++) {
1071 		dentry = d_alloc_name(dir, names[i]);
1072 		if (!dentry) {
1073 			ret = -ENOMEM;
1074 			goto err;
1075 		}
1076 		inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1077 		if (!inode) {
1078 			ret = -ENOMEM;
1079 			goto err;
1080 		}
1081 
1082 		len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1083 		if (len < 0) {
1084 			ret = -EINVAL;
1085 			goto err;
1086 		} else if (len >= PAGE_SIZE) {
1087 			ret = -ENAMETOOLONG;
1088 			goto err;
1089 		}
1090 		isec = (struct inode_security_struct *)inode->i_security;
1091 		ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1092 		if (ret)
1093 			goto err;
1094 		isec->sid = sid;
1095 		isec->initialized = 1;
1096 		inode->i_fop = &sel_bool_ops;
1097 		inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1098 		d_add(dentry, inode);
1099 	}
1100 	bool_num = num;
1101 	bool_pending_names = names;
1102 	bool_pending_values = values;
1103 out:
1104 	free_page((unsigned long)page);
1105 	return ret;
1106 err:
1107 	if (names) {
1108 		for (i = 0; i < num; i++)
1109 			kfree(names[i]);
1110 		kfree(names);
1111 	}
1112 	kfree(values);
1113 	sel_remove_entries(dir);
1114 	ret = -ENOMEM;
1115 	goto out;
1116 }
1117 
1118 #define NULL_FILE_NAME "null"
1119 
1120 struct dentry *selinux_null;
1121 
1122 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1123 					    size_t count, loff_t *ppos)
1124 {
1125 	char tmpbuf[TMPBUFLEN];
1126 	ssize_t length;
1127 
1128 	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1129 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1130 }
1131 
1132 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1133 					     const char __user *buf,
1134 					     size_t count, loff_t *ppos)
1135 
1136 {
1137 	char *page;
1138 	ssize_t ret;
1139 	int new_value;
1140 
1141 	if (count >= PAGE_SIZE) {
1142 		ret = -ENOMEM;
1143 		goto out;
1144 	}
1145 
1146 	if (*ppos != 0) {
1147 		/* No partial writes. */
1148 		ret = -EINVAL;
1149 		goto out;
1150 	}
1151 
1152 	page = (char *)get_zeroed_page(GFP_KERNEL);
1153 	if (!page) {
1154 		ret = -ENOMEM;
1155 		goto out;
1156 	}
1157 
1158 	if (copy_from_user(page, buf, count)) {
1159 		ret = -EFAULT;
1160 		goto out_free;
1161 	}
1162 
1163 	if (sscanf(page, "%u", &new_value) != 1) {
1164 		ret = -EINVAL;
1165 		goto out;
1166 	}
1167 
1168 	if (new_value != avc_cache_threshold) {
1169 		ret = task_has_security(current, SECURITY__SETSECPARAM);
1170 		if (ret)
1171 			goto out_free;
1172 		avc_cache_threshold = new_value;
1173 	}
1174 	ret = count;
1175 out_free:
1176 	free_page((unsigned long)page);
1177 out:
1178 	return ret;
1179 }
1180 
1181 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1182 				       size_t count, loff_t *ppos)
1183 {
1184 	char *page;
1185 	ssize_t ret = 0;
1186 
1187 	page = (char *)__get_free_page(GFP_KERNEL);
1188 	if (!page) {
1189 		ret = -ENOMEM;
1190 		goto out;
1191 	}
1192 	ret = avc_get_hash_stats(page);
1193 	if (ret >= 0)
1194 		ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1195 	free_page((unsigned long)page);
1196 out:
1197 	return ret;
1198 }
1199 
1200 static const struct file_operations sel_avc_cache_threshold_ops = {
1201 	.read		= sel_read_avc_cache_threshold,
1202 	.write		= sel_write_avc_cache_threshold,
1203 };
1204 
1205 static const struct file_operations sel_avc_hash_stats_ops = {
1206 	.read		= sel_read_avc_hash_stats,
1207 };
1208 
1209 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1210 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1211 {
1212 	int cpu;
1213 
1214 	for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1215 		if (!cpu_possible(cpu))
1216 			continue;
1217 		*idx = cpu + 1;
1218 		return &per_cpu(avc_cache_stats, cpu);
1219 	}
1220 	return NULL;
1221 }
1222 
1223 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1224 {
1225 	loff_t n = *pos - 1;
1226 
1227 	if (*pos == 0)
1228 		return SEQ_START_TOKEN;
1229 
1230 	return sel_avc_get_stat_idx(&n);
1231 }
1232 
1233 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1234 {
1235 	return sel_avc_get_stat_idx(pos);
1236 }
1237 
1238 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1239 {
1240 	struct avc_cache_stats *st = v;
1241 
1242 	if (v == SEQ_START_TOKEN)
1243 		seq_printf(seq, "lookups hits misses allocations reclaims "
1244 			   "frees\n");
1245 	else
1246 		seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1247 			   st->hits, st->misses, st->allocations,
1248 			   st->reclaims, st->frees);
1249 	return 0;
1250 }
1251 
1252 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1253 { }
1254 
1255 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1256 	.start		= sel_avc_stats_seq_start,
1257 	.next		= sel_avc_stats_seq_next,
1258 	.show		= sel_avc_stats_seq_show,
1259 	.stop		= sel_avc_stats_seq_stop,
1260 };
1261 
1262 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1263 {
1264 	return seq_open(file, &sel_avc_cache_stats_seq_ops);
1265 }
1266 
1267 static const struct file_operations sel_avc_cache_stats_ops = {
1268 	.open		= sel_open_avc_cache_stats,
1269 	.read		= seq_read,
1270 	.llseek		= seq_lseek,
1271 	.release	= seq_release,
1272 };
1273 #endif
1274 
1275 static int sel_make_avc_files(struct dentry *dir)
1276 {
1277 	int i, ret = 0;
1278 	static struct tree_descr files[] = {
1279 		{ "cache_threshold",
1280 		  &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1281 		{ "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1282 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1283 		{ "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1284 #endif
1285 	};
1286 
1287 	for (i = 0; i < ARRAY_SIZE(files); i++) {
1288 		struct inode *inode;
1289 		struct dentry *dentry;
1290 
1291 		dentry = d_alloc_name(dir, files[i].name);
1292 		if (!dentry) {
1293 			ret = -ENOMEM;
1294 			goto out;
1295 		}
1296 
1297 		inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1298 		if (!inode) {
1299 			ret = -ENOMEM;
1300 			goto out;
1301 		}
1302 		inode->i_fop = files[i].ops;
1303 		inode->i_ino = ++sel_last_ino;
1304 		d_add(dentry, inode);
1305 	}
1306 out:
1307 	return ret;
1308 }
1309 
1310 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1311 				size_t count, loff_t *ppos)
1312 {
1313 	struct inode *inode;
1314 	char *con;
1315 	u32 sid, len;
1316 	ssize_t ret;
1317 
1318 	inode = file->f_path.dentry->d_inode;
1319 	sid = inode->i_ino&SEL_INO_MASK;
1320 	ret = security_sid_to_context(sid, &con, &len);
1321 	if (ret < 0)
1322 		return ret;
1323 
1324 	ret = simple_read_from_buffer(buf, count, ppos, con, len);
1325 	kfree(con);
1326 	return ret;
1327 }
1328 
1329 static const struct file_operations sel_initcon_ops = {
1330 	.read		= sel_read_initcon,
1331 };
1332 
1333 static int sel_make_initcon_files(struct dentry *dir)
1334 {
1335 	int i, ret = 0;
1336 
1337 	for (i = 1; i <= SECINITSID_NUM; i++) {
1338 		struct inode *inode;
1339 		struct dentry *dentry;
1340 		dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1341 		if (!dentry) {
1342 			ret = -ENOMEM;
1343 			goto out;
1344 		}
1345 
1346 		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1347 		if (!inode) {
1348 			ret = -ENOMEM;
1349 			goto out;
1350 		}
1351 		inode->i_fop = &sel_initcon_ops;
1352 		inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1353 		d_add(dentry, inode);
1354 	}
1355 out:
1356 	return ret;
1357 }
1358 
1359 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1360 {
1361 	return a / b - (a % b < 0);
1362 }
1363 
1364 static inline unsigned long sel_class_to_ino(u16 class)
1365 {
1366 	return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1367 }
1368 
1369 static inline u16 sel_ino_to_class(unsigned long ino)
1370 {
1371 	return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1372 }
1373 
1374 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1375 {
1376 	return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1377 }
1378 
1379 static inline u32 sel_ino_to_perm(unsigned long ino)
1380 {
1381 	return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1382 }
1383 
1384 static ssize_t sel_read_class(struct file *file, char __user *buf,
1385 				size_t count, loff_t *ppos)
1386 {
1387 	ssize_t rc, len;
1388 	char *page;
1389 	unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1390 
1391 	page = (char *)__get_free_page(GFP_KERNEL);
1392 	if (!page) {
1393 		rc = -ENOMEM;
1394 		goto out;
1395 	}
1396 
1397 	len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1398 	rc = simple_read_from_buffer(buf, count, ppos, page, len);
1399 	free_page((unsigned long)page);
1400 out:
1401 	return rc;
1402 }
1403 
1404 static const struct file_operations sel_class_ops = {
1405 	.read		= sel_read_class,
1406 };
1407 
1408 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1409 				size_t count, loff_t *ppos)
1410 {
1411 	ssize_t rc, len;
1412 	char *page;
1413 	unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1414 
1415 	page = (char *)__get_free_page(GFP_KERNEL);
1416 	if (!page) {
1417 		rc = -ENOMEM;
1418 		goto out;
1419 	}
1420 
1421 	len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1422 	rc = simple_read_from_buffer(buf, count, ppos, page, len);
1423 	free_page((unsigned long)page);
1424 out:
1425 	return rc;
1426 }
1427 
1428 static const struct file_operations sel_perm_ops = {
1429 	.read		= sel_read_perm,
1430 };
1431 
1432 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1433 				  size_t count, loff_t *ppos)
1434 {
1435 	int value;
1436 	char tmpbuf[TMPBUFLEN];
1437 	ssize_t length;
1438 	unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1439 
1440 	value = security_policycap_supported(i_ino & SEL_INO_MASK);
1441 	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1442 
1443 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1444 }
1445 
1446 static const struct file_operations sel_policycap_ops = {
1447 	.read		= sel_read_policycap,
1448 };
1449 
1450 static int sel_make_perm_files(char *objclass, int classvalue,
1451 				struct dentry *dir)
1452 {
1453 	int i, rc = 0, nperms;
1454 	char **perms;
1455 
1456 	rc = security_get_permissions(objclass, &perms, &nperms);
1457 	if (rc)
1458 		goto out;
1459 
1460 	for (i = 0; i < nperms; i++) {
1461 		struct inode *inode;
1462 		struct dentry *dentry;
1463 
1464 		dentry = d_alloc_name(dir, perms[i]);
1465 		if (!dentry) {
1466 			rc = -ENOMEM;
1467 			goto out1;
1468 		}
1469 
1470 		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1471 		if (!inode) {
1472 			rc = -ENOMEM;
1473 			goto out1;
1474 		}
1475 		inode->i_fop = &sel_perm_ops;
1476 		/* i+1 since perm values are 1-indexed */
1477 		inode->i_ino = sel_perm_to_ino(classvalue, i+1);
1478 		d_add(dentry, inode);
1479 	}
1480 
1481 out1:
1482 	for (i = 0; i < nperms; i++)
1483 		kfree(perms[i]);
1484 	kfree(perms);
1485 out:
1486 	return rc;
1487 }
1488 
1489 static int sel_make_class_dir_entries(char *classname, int index,
1490 					struct dentry *dir)
1491 {
1492 	struct dentry *dentry = NULL;
1493 	struct inode *inode = NULL;
1494 	int rc;
1495 
1496 	dentry = d_alloc_name(dir, "index");
1497 	if (!dentry) {
1498 		rc = -ENOMEM;
1499 		goto out;
1500 	}
1501 
1502 	inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1503 	if (!inode) {
1504 		rc = -ENOMEM;
1505 		goto out;
1506 	}
1507 
1508 	inode->i_fop = &sel_class_ops;
1509 	inode->i_ino = sel_class_to_ino(index);
1510 	d_add(dentry, inode);
1511 
1512 	dentry = d_alloc_name(dir, "perms");
1513 	if (!dentry) {
1514 		rc = -ENOMEM;
1515 		goto out;
1516 	}
1517 
1518 	rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1519 	if (rc)
1520 		goto out;
1521 
1522 	rc = sel_make_perm_files(classname, index, dentry);
1523 
1524 out:
1525 	return rc;
1526 }
1527 
1528 static void sel_remove_classes(void)
1529 {
1530 	struct list_head *class_node;
1531 
1532 	list_for_each(class_node, &class_dir->d_subdirs) {
1533 		struct dentry *class_subdir = list_entry(class_node,
1534 					struct dentry, d_u.d_child);
1535 		struct list_head *class_subdir_node;
1536 
1537 		list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1538 			struct dentry *d = list_entry(class_subdir_node,
1539 						struct dentry, d_u.d_child);
1540 
1541 			if (d->d_inode)
1542 				if (d->d_inode->i_mode & S_IFDIR)
1543 					sel_remove_entries(d);
1544 		}
1545 
1546 		sel_remove_entries(class_subdir);
1547 	}
1548 
1549 	sel_remove_entries(class_dir);
1550 }
1551 
1552 static int sel_make_classes(void)
1553 {
1554 	int rc = 0, nclasses, i;
1555 	char **classes;
1556 
1557 	/* delete any existing entries */
1558 	sel_remove_classes();
1559 
1560 	rc = security_get_classes(&classes, &nclasses);
1561 	if (rc < 0)
1562 		goto out;
1563 
1564 	/* +2 since classes are 1-indexed */
1565 	last_class_ino = sel_class_to_ino(nclasses+2);
1566 
1567 	for (i = 0; i < nclasses; i++) {
1568 		struct dentry *class_name_dir;
1569 
1570 		class_name_dir = d_alloc_name(class_dir, classes[i]);
1571 		if (!class_name_dir) {
1572 			rc = -ENOMEM;
1573 			goto out1;
1574 		}
1575 
1576 		rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1577 				&last_class_ino);
1578 		if (rc)
1579 			goto out1;
1580 
1581 		/* i+1 since class values are 1-indexed */
1582 		rc = sel_make_class_dir_entries(classes[i], i+1,
1583 				class_name_dir);
1584 		if (rc)
1585 			goto out1;
1586 	}
1587 
1588 out1:
1589 	for (i = 0; i < nclasses; i++)
1590 		kfree(classes[i]);
1591 	kfree(classes);
1592 out:
1593 	return rc;
1594 }
1595 
1596 static int sel_make_policycap(void)
1597 {
1598 	unsigned int iter;
1599 	struct dentry *dentry = NULL;
1600 	struct inode *inode = NULL;
1601 
1602 	sel_remove_entries(policycap_dir);
1603 
1604 	for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1605 		if (iter < ARRAY_SIZE(policycap_names))
1606 			dentry = d_alloc_name(policycap_dir,
1607 					      policycap_names[iter]);
1608 		else
1609 			dentry = d_alloc_name(policycap_dir, "unknown");
1610 
1611 		if (dentry == NULL)
1612 			return -ENOMEM;
1613 
1614 		inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1615 		if (inode == NULL)
1616 			return -ENOMEM;
1617 
1618 		inode->i_fop = &sel_policycap_ops;
1619 		inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1620 		d_add(dentry, inode);
1621 	}
1622 
1623 	return 0;
1624 }
1625 
1626 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1627 			unsigned long *ino)
1628 {
1629 	int ret = 0;
1630 	struct inode *inode;
1631 
1632 	inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1633 	if (!inode) {
1634 		ret = -ENOMEM;
1635 		goto out;
1636 	}
1637 	inode->i_op = &simple_dir_inode_operations;
1638 	inode->i_fop = &simple_dir_operations;
1639 	inode->i_ino = ++(*ino);
1640 	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1641 	inc_nlink(inode);
1642 	d_add(dentry, inode);
1643 	/* bump link count on parent directory, too */
1644 	inc_nlink(dir);
1645 out:
1646 	return ret;
1647 }
1648 
1649 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1650 {
1651 	int ret;
1652 	struct dentry *dentry;
1653 	struct inode *inode, *root_inode;
1654 	struct inode_security_struct *isec;
1655 
1656 	static struct tree_descr selinux_files[] = {
1657 		[SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1658 		[SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1659 		[SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1660 		[SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1661 		[SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1662 		[SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1663 		[SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1664 		[SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1665 		[SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1666 		[SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1667 		[SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1668 		[SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1669 		[SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1670 		[SEL_COMPAT_NET] = {"compat_net", &sel_compat_net_ops, S_IRUGO|S_IWUSR},
1671 		[SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1672 		[SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1673 		/* last one */ {""}
1674 	};
1675 	ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1676 	if (ret)
1677 		goto err;
1678 
1679 	root_inode = sb->s_root->d_inode;
1680 
1681 	dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1682 	if (!dentry) {
1683 		ret = -ENOMEM;
1684 		goto err;
1685 	}
1686 
1687 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1688 	if (ret)
1689 		goto err;
1690 
1691 	bool_dir = dentry;
1692 
1693 	dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1694 	if (!dentry) {
1695 		ret = -ENOMEM;
1696 		goto err;
1697 	}
1698 
1699 	inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1700 	if (!inode) {
1701 		ret = -ENOMEM;
1702 		goto err;
1703 	}
1704 	inode->i_ino = ++sel_last_ino;
1705 	isec = (struct inode_security_struct *)inode->i_security;
1706 	isec->sid = SECINITSID_DEVNULL;
1707 	isec->sclass = SECCLASS_CHR_FILE;
1708 	isec->initialized = 1;
1709 
1710 	init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1711 	d_add(dentry, inode);
1712 	selinux_null = dentry;
1713 
1714 	dentry = d_alloc_name(sb->s_root, "avc");
1715 	if (!dentry) {
1716 		ret = -ENOMEM;
1717 		goto err;
1718 	}
1719 
1720 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1721 	if (ret)
1722 		goto err;
1723 
1724 	ret = sel_make_avc_files(dentry);
1725 	if (ret)
1726 		goto err;
1727 
1728 	dentry = d_alloc_name(sb->s_root, "initial_contexts");
1729 	if (!dentry) {
1730 		ret = -ENOMEM;
1731 		goto err;
1732 	}
1733 
1734 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1735 	if (ret)
1736 		goto err;
1737 
1738 	ret = sel_make_initcon_files(dentry);
1739 	if (ret)
1740 		goto err;
1741 
1742 	dentry = d_alloc_name(sb->s_root, "class");
1743 	if (!dentry) {
1744 		ret = -ENOMEM;
1745 		goto err;
1746 	}
1747 
1748 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1749 	if (ret)
1750 		goto err;
1751 
1752 	class_dir = dentry;
1753 
1754 	dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1755 	if (!dentry) {
1756 		ret = -ENOMEM;
1757 		goto err;
1758 	}
1759 
1760 	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1761 	if (ret)
1762 		goto err;
1763 
1764 	policycap_dir = dentry;
1765 
1766 out:
1767 	return ret;
1768 err:
1769 	printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1770 		__func__);
1771 	goto out;
1772 }
1773 
1774 static int sel_get_sb(struct file_system_type *fs_type,
1775 		      int flags, const char *dev_name, void *data,
1776 		      struct vfsmount *mnt)
1777 {
1778 	return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
1779 }
1780 
1781 static struct file_system_type sel_fs_type = {
1782 	.name		= "selinuxfs",
1783 	.get_sb		= sel_get_sb,
1784 	.kill_sb	= kill_litter_super,
1785 };
1786 
1787 struct vfsmount *selinuxfs_mount;
1788 
1789 static int __init init_sel_fs(void)
1790 {
1791 	int err;
1792 
1793 	if (!selinux_enabled)
1794 		return 0;
1795 	err = register_filesystem(&sel_fs_type);
1796 	if (!err) {
1797 		selinuxfs_mount = kern_mount(&sel_fs_type);
1798 		if (IS_ERR(selinuxfs_mount)) {
1799 			printk(KERN_ERR "selinuxfs:  could not mount!\n");
1800 			err = PTR_ERR(selinuxfs_mount);
1801 			selinuxfs_mount = NULL;
1802 		}
1803 	}
1804 	return err;
1805 }
1806 
1807 __initcall(init_sel_fs);
1808 
1809 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1810 void exit_sel_fs(void)
1811 {
1812 	unregister_filesystem(&sel_fs_type);
1813 }
1814 #endif
1815