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