1/* Updated: Karl MacMillan <kmacmillan@tresys.com>
2 *
3 *	Added conditional policy language extensions
4 *
5 *  Updated: Hewlett-Packard <paul@paul-moore.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#include <linux/kobject.h>
32#include <linux/ctype.h>
33
34/* selinuxfs pseudo filesystem for exporting the security policy API.
35   Based on the proc code and the fs/nfsd/nfsctl.c code. */
36
37#include "flask.h"
38#include "avc.h"
39#include "avc_ss.h"
40#include "security.h"
41#include "objsec.h"
42#include "conditional.h"
43
44/* Policy capability filenames */
45static char *policycap_names[] = {
46	"network_peer_controls",
47	"open_perms",
48	"redhat1",
49	"always_check_network"
50};
51
52unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
53
54static int __init checkreqprot_setup(char *str)
55{
56	unsigned long checkreqprot;
57	if (!kstrtoul(str, 0, &checkreqprot))
58		selinux_checkreqprot = checkreqprot ? 1 : 0;
59	return 1;
60}
61__setup("checkreqprot=", checkreqprot_setup);
62
63static DEFINE_MUTEX(sel_mutex);
64
65/* global data for booleans */
66static struct dentry *bool_dir;
67static int bool_num;
68static char **bool_pending_names;
69static int *bool_pending_values;
70
71/* global data for classes */
72static struct dentry *class_dir;
73static unsigned long last_class_ino;
74
75static char policy_opened;
76
77/* global data for policy capabilities */
78static struct dentry *policycap_dir;
79
80/* Check whether a task is allowed to use a security operation. */
81static int task_has_security(struct task_struct *tsk,
82			     u32 perms)
83{
84	const struct task_security_struct *tsec;
85	u32 sid = 0;
86
87	rcu_read_lock();
88	tsec = __task_cred(tsk)->security;
89	if (tsec)
90		sid = tsec->sid;
91	rcu_read_unlock();
92	if (!tsec)
93		return -EACCES;
94
95	return avc_has_perm(sid, SECINITSID_SECURITY,
96			    SECCLASS_SECURITY, perms, NULL);
97}
98
99enum sel_inos {
100	SEL_ROOT_INO = 2,
101	SEL_LOAD,	/* load policy */
102	SEL_ENFORCE,	/* get or set enforcing status */
103	SEL_CONTEXT,	/* validate context */
104	SEL_ACCESS,	/* compute access decision */
105	SEL_CREATE,	/* compute create labeling decision */
106	SEL_RELABEL,	/* compute relabeling decision */
107	SEL_USER,	/* compute reachable user contexts */
108	SEL_POLICYVERS,	/* return policy version for this kernel */
109	SEL_COMMIT_BOOLS, /* commit new boolean values */
110	SEL_MLS,	/* return if MLS policy is enabled */
111	SEL_DISABLE,	/* disable SELinux until next reboot */
112	SEL_MEMBER,	/* compute polyinstantiation membership decision */
113	SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
114	SEL_COMPAT_NET,	/* whether to use old compat network packet controls */
115	SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
116	SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
117	SEL_STATUS,	/* export current status using mmap() */
118	SEL_POLICY,	/* allow userspace to read the in kernel policy */
119	SEL_INO_NEXT,	/* The next inode number to use */
120};
121
122static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
123
124#define SEL_INITCON_INO_OFFSET		0x01000000
125#define SEL_BOOL_INO_OFFSET		0x02000000
126#define SEL_CLASS_INO_OFFSET		0x04000000
127#define SEL_POLICYCAP_INO_OFFSET	0x08000000
128#define SEL_INO_MASK			0x00ffffff
129
130#define TMPBUFLEN	12
131static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
132				size_t count, loff_t *ppos)
133{
134	char tmpbuf[TMPBUFLEN];
135	ssize_t length;
136
137	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
138	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
139}
140
141#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
142static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
143				 size_t count, loff_t *ppos)
144
145{
146	char *page = NULL;
147	ssize_t length;
148	int new_value;
149
150	length = -ENOMEM;
151	if (count >= PAGE_SIZE)
152		goto out;
153
154	/* No partial writes. */
155	length = -EINVAL;
156	if (*ppos != 0)
157		goto out;
158
159	length = -ENOMEM;
160	page = (char *)get_zeroed_page(GFP_KERNEL);
161	if (!page)
162		goto out;
163
164	length = -EFAULT;
165	if (copy_from_user(page, buf, count))
166		goto out;
167
168	length = -EINVAL;
169	if (sscanf(page, "%d", &new_value) != 1)
170		goto out;
171
172	if (new_value != selinux_enforcing) {
173		length = task_has_security(current, SECURITY__SETENFORCE);
174		if (length)
175			goto out;
176		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
177			"enforcing=%d old_enforcing=%d auid=%u ses=%u",
178			new_value, selinux_enforcing,
179			from_kuid(&init_user_ns, audit_get_loginuid(current)),
180			audit_get_sessionid(current));
181		selinux_enforcing = new_value;
182		if (selinux_enforcing)
183			avc_ss_reset(0);
184		selnl_notify_setenforce(selinux_enforcing);
185		selinux_status_update_setenforce(selinux_enforcing);
186	}
187	length = count;
188out:
189	free_page((unsigned long) page);
190	return length;
191}
192#else
193#define sel_write_enforce NULL
194#endif
195
196static const struct file_operations sel_enforce_ops = {
197	.read		= sel_read_enforce,
198	.write		= sel_write_enforce,
199	.llseek		= generic_file_llseek,
200};
201
202static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
203					size_t count, loff_t *ppos)
204{
205	char tmpbuf[TMPBUFLEN];
206	ssize_t length;
207	ino_t ino = file_inode(filp)->i_ino;
208	int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
209		security_get_reject_unknown() : !security_get_allow_unknown();
210
211	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
212	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
213}
214
215static const struct file_operations sel_handle_unknown_ops = {
216	.read		= sel_read_handle_unknown,
217	.llseek		= generic_file_llseek,
218};
219
220static int sel_open_handle_status(struct inode *inode, struct file *filp)
221{
222	struct page    *status = selinux_kernel_status_page();
223
224	if (!status)
225		return -ENOMEM;
226
227	filp->private_data = status;
228
229	return 0;
230}
231
232static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
233				      size_t count, loff_t *ppos)
234{
235	struct page    *status = filp->private_data;
236
237	BUG_ON(!status);
238
239	return simple_read_from_buffer(buf, count, ppos,
240				       page_address(status),
241				       sizeof(struct selinux_kernel_status));
242}
243
244static int sel_mmap_handle_status(struct file *filp,
245				  struct vm_area_struct *vma)
246{
247	struct page    *status = filp->private_data;
248	unsigned long	size = vma->vm_end - vma->vm_start;
249
250	BUG_ON(!status);
251
252	/* only allows one page from the head */
253	if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
254		return -EIO;
255	/* disallow writable mapping */
256	if (vma->vm_flags & VM_WRITE)
257		return -EPERM;
258	/* disallow mprotect() turns it into writable */
259	vma->vm_flags &= ~VM_MAYWRITE;
260
261	return remap_pfn_range(vma, vma->vm_start,
262			       page_to_pfn(status),
263			       size, vma->vm_page_prot);
264}
265
266static const struct file_operations sel_handle_status_ops = {
267	.open		= sel_open_handle_status,
268	.read		= sel_read_handle_status,
269	.mmap		= sel_mmap_handle_status,
270	.llseek		= generic_file_llseek,
271};
272
273#ifdef CONFIG_SECURITY_SELINUX_DISABLE
274static ssize_t sel_write_disable(struct file *file, const char __user *buf,
275				 size_t count, loff_t *ppos)
276
277{
278	char *page = NULL;
279	ssize_t length;
280	int new_value;
281
282	length = -ENOMEM;
283	if (count >= PAGE_SIZE)
284		goto out;
285
286	/* No partial writes. */
287	length = -EINVAL;
288	if (*ppos != 0)
289		goto out;
290
291	length = -ENOMEM;
292	page = (char *)get_zeroed_page(GFP_KERNEL);
293	if (!page)
294		goto out;
295
296	length = -EFAULT;
297	if (copy_from_user(page, buf, count))
298		goto out;
299
300	length = -EINVAL;
301	if (sscanf(page, "%d", &new_value) != 1)
302		goto out;
303
304	if (new_value) {
305		length = selinux_disable();
306		if (length)
307			goto out;
308		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
309			"selinux=0 auid=%u ses=%u",
310			from_kuid(&init_user_ns, audit_get_loginuid(current)),
311			audit_get_sessionid(current));
312	}
313
314	length = count;
315out:
316	free_page((unsigned long) page);
317	return length;
318}
319#else
320#define sel_write_disable NULL
321#endif
322
323static const struct file_operations sel_disable_ops = {
324	.write		= sel_write_disable,
325	.llseek		= generic_file_llseek,
326};
327
328static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
329				   size_t count, loff_t *ppos)
330{
331	char tmpbuf[TMPBUFLEN];
332	ssize_t length;
333
334	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
335	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
336}
337
338static const struct file_operations sel_policyvers_ops = {
339	.read		= sel_read_policyvers,
340	.llseek		= generic_file_llseek,
341};
342
343/* declaration for sel_write_load */
344static int sel_make_bools(void);
345static int sel_make_classes(void);
346static int sel_make_policycap(void);
347
348/* declaration for sel_make_class_dirs */
349static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
350			unsigned long *ino);
351
352static ssize_t sel_read_mls(struct file *filp, char __user *buf,
353				size_t count, loff_t *ppos)
354{
355	char tmpbuf[TMPBUFLEN];
356	ssize_t length;
357
358	length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
359			   security_mls_enabled());
360	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
361}
362
363static const struct file_operations sel_mls_ops = {
364	.read		= sel_read_mls,
365	.llseek		= generic_file_llseek,
366};
367
368struct policy_load_memory {
369	size_t len;
370	void *data;
371};
372
373static int sel_open_policy(struct inode *inode, struct file *filp)
374{
375	struct policy_load_memory *plm = NULL;
376	int rc;
377
378	BUG_ON(filp->private_data);
379
380	mutex_lock(&sel_mutex);
381
382	rc = task_has_security(current, SECURITY__READ_POLICY);
383	if (rc)
384		goto err;
385
386	rc = -EBUSY;
387	if (policy_opened)
388		goto err;
389
390	rc = -ENOMEM;
391	plm = kzalloc(sizeof(*plm), GFP_KERNEL);
392	if (!plm)
393		goto err;
394
395	if (i_size_read(inode) != security_policydb_len()) {
396		mutex_lock(&inode->i_mutex);
397		i_size_write(inode, security_policydb_len());
398		mutex_unlock(&inode->i_mutex);
399	}
400
401	rc = security_read_policy(&plm->data, &plm->len);
402	if (rc)
403		goto err;
404
405	policy_opened = 1;
406
407	filp->private_data = plm;
408
409	mutex_unlock(&sel_mutex);
410
411	return 0;
412err:
413	mutex_unlock(&sel_mutex);
414
415	if (plm)
416		vfree(plm->data);
417	kfree(plm);
418	return rc;
419}
420
421static int sel_release_policy(struct inode *inode, struct file *filp)
422{
423	struct policy_load_memory *plm = filp->private_data;
424
425	BUG_ON(!plm);
426
427	policy_opened = 0;
428
429	vfree(plm->data);
430	kfree(plm);
431
432	return 0;
433}
434
435static ssize_t sel_read_policy(struct file *filp, char __user *buf,
436			       size_t count, loff_t *ppos)
437{
438	struct policy_load_memory *plm = filp->private_data;
439	int ret;
440
441	mutex_lock(&sel_mutex);
442
443	ret = task_has_security(current, SECURITY__READ_POLICY);
444	if (ret)
445		goto out;
446
447	ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
448out:
449	mutex_unlock(&sel_mutex);
450	return ret;
451}
452
453static int sel_mmap_policy_fault(struct vm_area_struct *vma,
454				 struct vm_fault *vmf)
455{
456	struct policy_load_memory *plm = vma->vm_file->private_data;
457	unsigned long offset;
458	struct page *page;
459
460	if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
461		return VM_FAULT_SIGBUS;
462
463	offset = vmf->pgoff << PAGE_SHIFT;
464	if (offset >= roundup(plm->len, PAGE_SIZE))
465		return VM_FAULT_SIGBUS;
466
467	page = vmalloc_to_page(plm->data + offset);
468	get_page(page);
469
470	vmf->page = page;
471
472	return 0;
473}
474
475static struct vm_operations_struct sel_mmap_policy_ops = {
476	.fault = sel_mmap_policy_fault,
477	.page_mkwrite = sel_mmap_policy_fault,
478};
479
480static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
481{
482	if (vma->vm_flags & VM_SHARED) {
483		/* do not allow mprotect to make mapping writable */
484		vma->vm_flags &= ~VM_MAYWRITE;
485
486		if (vma->vm_flags & VM_WRITE)
487			return -EACCES;
488	}
489
490	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
491	vma->vm_ops = &sel_mmap_policy_ops;
492
493	return 0;
494}
495
496static const struct file_operations sel_policy_ops = {
497	.open		= sel_open_policy,
498	.read		= sel_read_policy,
499	.mmap		= sel_mmap_policy,
500	.release	= sel_release_policy,
501	.llseek		= generic_file_llseek,
502};
503
504static ssize_t sel_write_load(struct file *file, const char __user *buf,
505			      size_t count, loff_t *ppos)
506
507{
508	ssize_t length;
509	void *data = NULL;
510
511	mutex_lock(&sel_mutex);
512
513	length = task_has_security(current, SECURITY__LOAD_POLICY);
514	if (length)
515		goto out;
516
517	/* No partial writes. */
518	length = -EINVAL;
519	if (*ppos != 0)
520		goto out;
521
522	length = -EFBIG;
523	if (count > 64 * 1024 * 1024)
524		goto out;
525
526	length = -ENOMEM;
527	data = vmalloc(count);
528	if (!data)
529		goto out;
530
531	length = -EFAULT;
532	if (copy_from_user(data, buf, count) != 0)
533		goto out;
534
535	length = security_load_policy(data, count);
536	if (length)
537		goto out;
538
539	length = sel_make_bools();
540	if (length)
541		goto out1;
542
543	length = sel_make_classes();
544	if (length)
545		goto out1;
546
547	length = sel_make_policycap();
548	if (length)
549		goto out1;
550
551	length = count;
552
553out1:
554	audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
555		"policy loaded auid=%u ses=%u",
556		from_kuid(&init_user_ns, audit_get_loginuid(current)),
557		audit_get_sessionid(current));
558out:
559	mutex_unlock(&sel_mutex);
560	vfree(data);
561	return length;
562}
563
564static const struct file_operations sel_load_ops = {
565	.write		= sel_write_load,
566	.llseek		= generic_file_llseek,
567};
568
569static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
570{
571	char *canon = NULL;
572	u32 sid, len;
573	ssize_t length;
574
575	length = task_has_security(current, SECURITY__CHECK_CONTEXT);
576	if (length)
577		goto out;
578
579	length = security_context_to_sid(buf, size, &sid, GFP_KERNEL);
580	if (length)
581		goto out;
582
583	length = security_sid_to_context(sid, &canon, &len);
584	if (length)
585		goto out;
586
587	length = -ERANGE;
588	if (len > SIMPLE_TRANSACTION_LIMIT) {
589		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
590			"payload max\n", __func__, len);
591		goto out;
592	}
593
594	memcpy(buf, canon, len);
595	length = len;
596out:
597	kfree(canon);
598	return length;
599}
600
601static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
602				     size_t count, loff_t *ppos)
603{
604	char tmpbuf[TMPBUFLEN];
605	ssize_t length;
606
607	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
608	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
609}
610
611static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
612				      size_t count, loff_t *ppos)
613{
614	char *page = NULL;
615	ssize_t length;
616	unsigned int new_value;
617
618	length = task_has_security(current, SECURITY__SETCHECKREQPROT);
619	if (length)
620		goto out;
621
622	length = -ENOMEM;
623	if (count >= PAGE_SIZE)
624		goto out;
625
626	/* No partial writes. */
627	length = -EINVAL;
628	if (*ppos != 0)
629		goto out;
630
631	length = -ENOMEM;
632	page = (char *)get_zeroed_page(GFP_KERNEL);
633	if (!page)
634		goto out;
635
636	length = -EFAULT;
637	if (copy_from_user(page, buf, count))
638		goto out;
639
640	length = -EINVAL;
641	if (sscanf(page, "%u", &new_value) != 1)
642		goto out;
643
644	selinux_checkreqprot = new_value ? 1 : 0;
645	length = count;
646out:
647	free_page((unsigned long) page);
648	return length;
649}
650static const struct file_operations sel_checkreqprot_ops = {
651	.read		= sel_read_checkreqprot,
652	.write		= sel_write_checkreqprot,
653	.llseek		= generic_file_llseek,
654};
655
656/*
657 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
658 */
659static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
660static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
661static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
662static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
663static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
664
665static ssize_t (*write_op[])(struct file *, char *, size_t) = {
666	[SEL_ACCESS] = sel_write_access,
667	[SEL_CREATE] = sel_write_create,
668	[SEL_RELABEL] = sel_write_relabel,
669	[SEL_USER] = sel_write_user,
670	[SEL_MEMBER] = sel_write_member,
671	[SEL_CONTEXT] = sel_write_context,
672};
673
674static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
675{
676	ino_t ino = file_inode(file)->i_ino;
677	char *data;
678	ssize_t rv;
679
680	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
681		return -EINVAL;
682
683	data = simple_transaction_get(file, buf, size);
684	if (IS_ERR(data))
685		return PTR_ERR(data);
686
687	rv = write_op[ino](file, data, size);
688	if (rv > 0) {
689		simple_transaction_set(file, rv);
690		rv = size;
691	}
692	return rv;
693}
694
695static const struct file_operations transaction_ops = {
696	.write		= selinux_transaction_write,
697	.read		= simple_transaction_read,
698	.release	= simple_transaction_release,
699	.llseek		= generic_file_llseek,
700};
701
702/*
703 * payload - write methods
704 * If the method has a response, the response should be put in buf,
705 * and the length returned.  Otherwise return 0 or and -error.
706 */
707
708static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
709{
710	char *scon = NULL, *tcon = NULL;
711	u32 ssid, tsid;
712	u16 tclass;
713	struct av_decision avd;
714	ssize_t length;
715
716	length = task_has_security(current, SECURITY__COMPUTE_AV);
717	if (length)
718		goto out;
719
720	length = -ENOMEM;
721	scon = kzalloc(size + 1, GFP_KERNEL);
722	if (!scon)
723		goto out;
724
725	length = -ENOMEM;
726	tcon = kzalloc(size + 1, GFP_KERNEL);
727	if (!tcon)
728		goto out;
729
730	length = -EINVAL;
731	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
732		goto out;
733
734	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid,
735					 GFP_KERNEL);
736	if (length)
737		goto out;
738
739	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid,
740					 GFP_KERNEL);
741	if (length)
742		goto out;
743
744	security_compute_av_user(ssid, tsid, tclass, &avd);
745
746	length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
747			  "%x %x %x %x %u %x",
748			  avd.allowed, 0xffffffff,
749			  avd.auditallow, avd.auditdeny,
750			  avd.seqno, avd.flags);
751out:
752	kfree(tcon);
753	kfree(scon);
754	return length;
755}
756
757static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
758{
759	char *scon = NULL, *tcon = NULL;
760	char *namebuf = NULL, *objname = NULL;
761	u32 ssid, tsid, newsid;
762	u16 tclass;
763	ssize_t length;
764	char *newcon = NULL;
765	u32 len;
766	int nargs;
767
768	length = task_has_security(current, SECURITY__COMPUTE_CREATE);
769	if (length)
770		goto out;
771
772	length = -ENOMEM;
773	scon = kzalloc(size + 1, GFP_KERNEL);
774	if (!scon)
775		goto out;
776
777	length = -ENOMEM;
778	tcon = kzalloc(size + 1, GFP_KERNEL);
779	if (!tcon)
780		goto out;
781
782	length = -ENOMEM;
783	namebuf = kzalloc(size + 1, GFP_KERNEL);
784	if (!namebuf)
785		goto out;
786
787	length = -EINVAL;
788	nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
789	if (nargs < 3 || nargs > 4)
790		goto out;
791	if (nargs == 4) {
792		/*
793		 * If and when the name of new object to be queried contains
794		 * either whitespace or multibyte characters, they shall be
795		 * encoded based on the percentage-encoding rule.
796		 * If not encoded, the sscanf logic picks up only left-half
797		 * of the supplied name; splitted by a whitespace unexpectedly.
798		 */
799		char   *r, *w;
800		int     c1, c2;
801
802		r = w = namebuf;
803		do {
804			c1 = *r++;
805			if (c1 == '+')
806				c1 = ' ';
807			else if (c1 == '%') {
808				c1 = hex_to_bin(*r++);
809				if (c1 < 0)
810					goto out;
811				c2 = hex_to_bin(*r++);
812				if (c2 < 0)
813					goto out;
814				c1 = (c1 << 4) | c2;
815			}
816			*w++ = c1;
817		} while (c1 != '\0');
818
819		objname = namebuf;
820	}
821
822	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid,
823					 GFP_KERNEL);
824	if (length)
825		goto out;
826
827	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid,
828					 GFP_KERNEL);
829	if (length)
830		goto out;
831
832	length = security_transition_sid_user(ssid, tsid, tclass,
833					      objname, &newsid);
834	if (length)
835		goto out;
836
837	length = security_sid_to_context(newsid, &newcon, &len);
838	if (length)
839		goto out;
840
841	length = -ERANGE;
842	if (len > SIMPLE_TRANSACTION_LIMIT) {
843		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
844			"payload max\n", __func__, len);
845		goto out;
846	}
847
848	memcpy(buf, newcon, len);
849	length = len;
850out:
851	kfree(newcon);
852	kfree(namebuf);
853	kfree(tcon);
854	kfree(scon);
855	return length;
856}
857
858static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
859{
860	char *scon = NULL, *tcon = NULL;
861	u32 ssid, tsid, newsid;
862	u16 tclass;
863	ssize_t length;
864	char *newcon = NULL;
865	u32 len;
866
867	length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
868	if (length)
869		goto out;
870
871	length = -ENOMEM;
872	scon = kzalloc(size + 1, GFP_KERNEL);
873	if (!scon)
874		goto out;
875
876	length = -ENOMEM;
877	tcon = kzalloc(size + 1, GFP_KERNEL);
878	if (!tcon)
879		goto out;
880
881	length = -EINVAL;
882	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
883		goto out;
884
885	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid,
886					 GFP_KERNEL);
887	if (length)
888		goto out;
889
890	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid,
891					 GFP_KERNEL);
892	if (length)
893		goto out;
894
895	length = security_change_sid(ssid, tsid, tclass, &newsid);
896	if (length)
897		goto out;
898
899	length = security_sid_to_context(newsid, &newcon, &len);
900	if (length)
901		goto out;
902
903	length = -ERANGE;
904	if (len > SIMPLE_TRANSACTION_LIMIT)
905		goto out;
906
907	memcpy(buf, newcon, len);
908	length = len;
909out:
910	kfree(newcon);
911	kfree(tcon);
912	kfree(scon);
913	return length;
914}
915
916static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
917{
918	char *con = NULL, *user = NULL, *ptr;
919	u32 sid, *sids = NULL;
920	ssize_t length;
921	char *newcon;
922	int i, rc;
923	u32 len, nsids;
924
925	length = task_has_security(current, SECURITY__COMPUTE_USER);
926	if (length)
927		goto out;
928
929	length = -ENOMEM;
930	con = kzalloc(size + 1, GFP_KERNEL);
931	if (!con)
932		goto out;
933
934	length = -ENOMEM;
935	user = kzalloc(size + 1, GFP_KERNEL);
936	if (!user)
937		goto out;
938
939	length = -EINVAL;
940	if (sscanf(buf, "%s %s", con, user) != 2)
941		goto out;
942
943	length = security_context_to_sid(con, strlen(con) + 1, &sid, GFP_KERNEL);
944	if (length)
945		goto out;
946
947	length = security_get_user_sids(sid, user, &sids, &nsids);
948	if (length)
949		goto out;
950
951	length = sprintf(buf, "%u", nsids) + 1;
952	ptr = buf + length;
953	for (i = 0; i < nsids; i++) {
954		rc = security_sid_to_context(sids[i], &newcon, &len);
955		if (rc) {
956			length = rc;
957			goto out;
958		}
959		if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
960			kfree(newcon);
961			length = -ERANGE;
962			goto out;
963		}
964		memcpy(ptr, newcon, len);
965		kfree(newcon);
966		ptr += len;
967		length += len;
968	}
969out:
970	kfree(sids);
971	kfree(user);
972	kfree(con);
973	return length;
974}
975
976static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
977{
978	char *scon = NULL, *tcon = NULL;
979	u32 ssid, tsid, newsid;
980	u16 tclass;
981	ssize_t length;
982	char *newcon = NULL;
983	u32 len;
984
985	length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
986	if (length)
987		goto out;
988
989	length = -ENOMEM;
990	scon = kzalloc(size + 1, GFP_KERNEL);
991	if (!scon)
992		goto out;
993
994	length = -ENOMEM;
995	tcon = kzalloc(size + 1, GFP_KERNEL);
996	if (!tcon)
997		goto out;
998
999	length = -EINVAL;
1000	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1001		goto out;
1002
1003	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid,
1004					 GFP_KERNEL);
1005	if (length)
1006		goto out;
1007
1008	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid,
1009					 GFP_KERNEL);
1010	if (length)
1011		goto out;
1012
1013	length = security_member_sid(ssid, tsid, tclass, &newsid);
1014	if (length)
1015		goto out;
1016
1017	length = security_sid_to_context(newsid, &newcon, &len);
1018	if (length)
1019		goto out;
1020
1021	length = -ERANGE;
1022	if (len > SIMPLE_TRANSACTION_LIMIT) {
1023		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
1024			"payload max\n", __func__, len);
1025		goto out;
1026	}
1027
1028	memcpy(buf, newcon, len);
1029	length = len;
1030out:
1031	kfree(newcon);
1032	kfree(tcon);
1033	kfree(scon);
1034	return length;
1035}
1036
1037static struct inode *sel_make_inode(struct super_block *sb, int mode)
1038{
1039	struct inode *ret = new_inode(sb);
1040
1041	if (ret) {
1042		ret->i_mode = mode;
1043		ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
1044	}
1045	return ret;
1046}
1047
1048static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1049			     size_t count, loff_t *ppos)
1050{
1051	char *page = NULL;
1052	ssize_t length;
1053	ssize_t ret;
1054	int cur_enforcing;
1055	unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1056	const char *name = filep->f_path.dentry->d_name.name;
1057
1058	mutex_lock(&sel_mutex);
1059
1060	ret = -EINVAL;
1061	if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1062		goto out;
1063
1064	ret = -ENOMEM;
1065	page = (char *)get_zeroed_page(GFP_KERNEL);
1066	if (!page)
1067		goto out;
1068
1069	cur_enforcing = security_get_bool_value(index);
1070	if (cur_enforcing < 0) {
1071		ret = cur_enforcing;
1072		goto out;
1073	}
1074	length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1075			  bool_pending_values[index]);
1076	ret = simple_read_from_buffer(buf, count, ppos, page, length);
1077out:
1078	mutex_unlock(&sel_mutex);
1079	free_page((unsigned long)page);
1080	return ret;
1081}
1082
1083static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1084			      size_t count, loff_t *ppos)
1085{
1086	char *page = NULL;
1087	ssize_t length;
1088	int new_value;
1089	unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1090	const char *name = filep->f_path.dentry->d_name.name;
1091
1092	mutex_lock(&sel_mutex);
1093
1094	length = task_has_security(current, SECURITY__SETBOOL);
1095	if (length)
1096		goto out;
1097
1098	length = -EINVAL;
1099	if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1100		goto out;
1101
1102	length = -ENOMEM;
1103	if (count >= PAGE_SIZE)
1104		goto out;
1105
1106	/* No partial writes. */
1107	length = -EINVAL;
1108	if (*ppos != 0)
1109		goto out;
1110
1111	length = -ENOMEM;
1112	page = (char *)get_zeroed_page(GFP_KERNEL);
1113	if (!page)
1114		goto out;
1115
1116	length = -EFAULT;
1117	if (copy_from_user(page, buf, count))
1118		goto out;
1119
1120	length = -EINVAL;
1121	if (sscanf(page, "%d", &new_value) != 1)
1122		goto out;
1123
1124	if (new_value)
1125		new_value = 1;
1126
1127	bool_pending_values[index] = new_value;
1128	length = count;
1129
1130out:
1131	mutex_unlock(&sel_mutex);
1132	free_page((unsigned long) page);
1133	return length;
1134}
1135
1136static const struct file_operations sel_bool_ops = {
1137	.read		= sel_read_bool,
1138	.write		= sel_write_bool,
1139	.llseek		= generic_file_llseek,
1140};
1141
1142static ssize_t sel_commit_bools_write(struct file *filep,
1143				      const char __user *buf,
1144				      size_t count, loff_t *ppos)
1145{
1146	char *page = NULL;
1147	ssize_t length;
1148	int new_value;
1149
1150	mutex_lock(&sel_mutex);
1151
1152	length = task_has_security(current, SECURITY__SETBOOL);
1153	if (length)
1154		goto out;
1155
1156	length = -ENOMEM;
1157	if (count >= PAGE_SIZE)
1158		goto out;
1159
1160	/* No partial writes. */
1161	length = -EINVAL;
1162	if (*ppos != 0)
1163		goto out;
1164
1165	length = -ENOMEM;
1166	page = (char *)get_zeroed_page(GFP_KERNEL);
1167	if (!page)
1168		goto out;
1169
1170	length = -EFAULT;
1171	if (copy_from_user(page, buf, count))
1172		goto out;
1173
1174	length = -EINVAL;
1175	if (sscanf(page, "%d", &new_value) != 1)
1176		goto out;
1177
1178	length = 0;
1179	if (new_value && bool_pending_values)
1180		length = security_set_bools(bool_num, bool_pending_values);
1181
1182	if (!length)
1183		length = count;
1184
1185out:
1186	mutex_unlock(&sel_mutex);
1187	free_page((unsigned long) page);
1188	return length;
1189}
1190
1191static const struct file_operations sel_commit_bools_ops = {
1192	.write		= sel_commit_bools_write,
1193	.llseek		= generic_file_llseek,
1194};
1195
1196static void sel_remove_entries(struct dentry *de)
1197{
1198	d_genocide(de);
1199	shrink_dcache_parent(de);
1200}
1201
1202#define BOOL_DIR_NAME "booleans"
1203
1204static int sel_make_bools(void)
1205{
1206	int i, ret;
1207	ssize_t len;
1208	struct dentry *dentry = NULL;
1209	struct dentry *dir = bool_dir;
1210	struct inode *inode = NULL;
1211	struct inode_security_struct *isec;
1212	char **names = NULL, *page;
1213	int num;
1214	int *values = NULL;
1215	u32 sid;
1216
1217	/* remove any existing files */
1218	for (i = 0; i < bool_num; i++)
1219		kfree(bool_pending_names[i]);
1220	kfree(bool_pending_names);
1221	kfree(bool_pending_values);
1222	bool_num = 0;
1223	bool_pending_names = NULL;
1224	bool_pending_values = NULL;
1225
1226	sel_remove_entries(dir);
1227
1228	ret = -ENOMEM;
1229	page = (char *)get_zeroed_page(GFP_KERNEL);
1230	if (!page)
1231		goto out;
1232
1233	ret = security_get_bools(&num, &names, &values);
1234	if (ret)
1235		goto out;
1236
1237	for (i = 0; i < num; i++) {
1238		ret = -ENOMEM;
1239		dentry = d_alloc_name(dir, names[i]);
1240		if (!dentry)
1241			goto out;
1242
1243		ret = -ENOMEM;
1244		inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1245		if (!inode)
1246			goto out;
1247
1248		ret = -ENAMETOOLONG;
1249		len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1250		if (len >= PAGE_SIZE)
1251			goto out;
1252
1253		isec = (struct inode_security_struct *)inode->i_security;
1254		ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1255		if (ret)
1256			goto out;
1257
1258		isec->sid = sid;
1259		isec->initialized = 1;
1260		inode->i_fop = &sel_bool_ops;
1261		inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1262		d_add(dentry, inode);
1263	}
1264	bool_num = num;
1265	bool_pending_names = names;
1266	bool_pending_values = values;
1267
1268	free_page((unsigned long)page);
1269	return 0;
1270out:
1271	free_page((unsigned long)page);
1272
1273	if (names) {
1274		for (i = 0; i < num; i++)
1275			kfree(names[i]);
1276		kfree(names);
1277	}
1278	kfree(values);
1279	sel_remove_entries(dir);
1280
1281	return ret;
1282}
1283
1284#define NULL_FILE_NAME "null"
1285
1286struct path selinux_null;
1287
1288static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1289					    size_t count, loff_t *ppos)
1290{
1291	char tmpbuf[TMPBUFLEN];
1292	ssize_t length;
1293
1294	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1295	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1296}
1297
1298static ssize_t sel_write_avc_cache_threshold(struct file *file,
1299					     const char __user *buf,
1300					     size_t count, loff_t *ppos)
1301
1302{
1303	char *page = NULL;
1304	ssize_t ret;
1305	int new_value;
1306
1307	ret = task_has_security(current, SECURITY__SETSECPARAM);
1308	if (ret)
1309		goto out;
1310
1311	ret = -ENOMEM;
1312	if (count >= PAGE_SIZE)
1313		goto out;
1314
1315	/* No partial writes. */
1316	ret = -EINVAL;
1317	if (*ppos != 0)
1318		goto out;
1319
1320	ret = -ENOMEM;
1321	page = (char *)get_zeroed_page(GFP_KERNEL);
1322	if (!page)
1323		goto out;
1324
1325	ret = -EFAULT;
1326	if (copy_from_user(page, buf, count))
1327		goto out;
1328
1329	ret = -EINVAL;
1330	if (sscanf(page, "%u", &new_value) != 1)
1331		goto out;
1332
1333	avc_cache_threshold = new_value;
1334
1335	ret = count;
1336out:
1337	free_page((unsigned long)page);
1338	return ret;
1339}
1340
1341static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1342				       size_t count, loff_t *ppos)
1343{
1344	char *page;
1345	ssize_t length;
1346
1347	page = (char *)__get_free_page(GFP_KERNEL);
1348	if (!page)
1349		return -ENOMEM;
1350
1351	length = avc_get_hash_stats(page);
1352	if (length >= 0)
1353		length = simple_read_from_buffer(buf, count, ppos, page, length);
1354	free_page((unsigned long)page);
1355
1356	return length;
1357}
1358
1359static const struct file_operations sel_avc_cache_threshold_ops = {
1360	.read		= sel_read_avc_cache_threshold,
1361	.write		= sel_write_avc_cache_threshold,
1362	.llseek		= generic_file_llseek,
1363};
1364
1365static const struct file_operations sel_avc_hash_stats_ops = {
1366	.read		= sel_read_avc_hash_stats,
1367	.llseek		= generic_file_llseek,
1368};
1369
1370#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1371static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1372{
1373	int cpu;
1374
1375	for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1376		if (!cpu_possible(cpu))
1377			continue;
1378		*idx = cpu + 1;
1379		return &per_cpu(avc_cache_stats, cpu);
1380	}
1381	return NULL;
1382}
1383
1384static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1385{
1386	loff_t n = *pos - 1;
1387
1388	if (*pos == 0)
1389		return SEQ_START_TOKEN;
1390
1391	return sel_avc_get_stat_idx(&n);
1392}
1393
1394static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1395{
1396	return sel_avc_get_stat_idx(pos);
1397}
1398
1399static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1400{
1401	struct avc_cache_stats *st = v;
1402
1403	if (v == SEQ_START_TOKEN)
1404		seq_printf(seq, "lookups hits misses allocations reclaims "
1405			   "frees\n");
1406	else {
1407		unsigned int lookups = st->lookups;
1408		unsigned int misses = st->misses;
1409		unsigned int hits = lookups - misses;
1410		seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1411			   hits, misses, st->allocations,
1412			   st->reclaims, st->frees);
1413	}
1414	return 0;
1415}
1416
1417static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1418{ }
1419
1420static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1421	.start		= sel_avc_stats_seq_start,
1422	.next		= sel_avc_stats_seq_next,
1423	.show		= sel_avc_stats_seq_show,
1424	.stop		= sel_avc_stats_seq_stop,
1425};
1426
1427static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1428{
1429	return seq_open(file, &sel_avc_cache_stats_seq_ops);
1430}
1431
1432static const struct file_operations sel_avc_cache_stats_ops = {
1433	.open		= sel_open_avc_cache_stats,
1434	.read		= seq_read,
1435	.llseek		= seq_lseek,
1436	.release	= seq_release,
1437};
1438#endif
1439
1440static int sel_make_avc_files(struct dentry *dir)
1441{
1442	int i;
1443	static struct tree_descr files[] = {
1444		{ "cache_threshold",
1445		  &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1446		{ "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1447#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1448		{ "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1449#endif
1450	};
1451
1452	for (i = 0; i < ARRAY_SIZE(files); i++) {
1453		struct inode *inode;
1454		struct dentry *dentry;
1455
1456		dentry = d_alloc_name(dir, files[i].name);
1457		if (!dentry)
1458			return -ENOMEM;
1459
1460		inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1461		if (!inode)
1462			return -ENOMEM;
1463
1464		inode->i_fop = files[i].ops;
1465		inode->i_ino = ++sel_last_ino;
1466		d_add(dentry, inode);
1467	}
1468
1469	return 0;
1470}
1471
1472static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1473				size_t count, loff_t *ppos)
1474{
1475	char *con;
1476	u32 sid, len;
1477	ssize_t ret;
1478
1479	sid = file_inode(file)->i_ino&SEL_INO_MASK;
1480	ret = security_sid_to_context(sid, &con, &len);
1481	if (ret)
1482		return ret;
1483
1484	ret = simple_read_from_buffer(buf, count, ppos, con, len);
1485	kfree(con);
1486	return ret;
1487}
1488
1489static const struct file_operations sel_initcon_ops = {
1490	.read		= sel_read_initcon,
1491	.llseek		= generic_file_llseek,
1492};
1493
1494static int sel_make_initcon_files(struct dentry *dir)
1495{
1496	int i;
1497
1498	for (i = 1; i <= SECINITSID_NUM; i++) {
1499		struct inode *inode;
1500		struct dentry *dentry;
1501		dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1502		if (!dentry)
1503			return -ENOMEM;
1504
1505		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1506		if (!inode)
1507			return -ENOMEM;
1508
1509		inode->i_fop = &sel_initcon_ops;
1510		inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1511		d_add(dentry, inode);
1512	}
1513
1514	return 0;
1515}
1516
1517static inline unsigned long sel_class_to_ino(u16 class)
1518{
1519	return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1520}
1521
1522static inline u16 sel_ino_to_class(unsigned long ino)
1523{
1524	return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1525}
1526
1527static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1528{
1529	return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1530}
1531
1532static inline u32 sel_ino_to_perm(unsigned long ino)
1533{
1534	return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1535}
1536
1537static ssize_t sel_read_class(struct file *file, char __user *buf,
1538				size_t count, loff_t *ppos)
1539{
1540	unsigned long ino = file_inode(file)->i_ino;
1541	char res[TMPBUFLEN];
1542	ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1543	return simple_read_from_buffer(buf, count, ppos, res, len);
1544}
1545
1546static const struct file_operations sel_class_ops = {
1547	.read		= sel_read_class,
1548	.llseek		= generic_file_llseek,
1549};
1550
1551static ssize_t sel_read_perm(struct file *file, char __user *buf,
1552				size_t count, loff_t *ppos)
1553{
1554	unsigned long ino = file_inode(file)->i_ino;
1555	char res[TMPBUFLEN];
1556	ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1557	return simple_read_from_buffer(buf, count, ppos, res, len);
1558}
1559
1560static const struct file_operations sel_perm_ops = {
1561	.read		= sel_read_perm,
1562	.llseek		= generic_file_llseek,
1563};
1564
1565static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1566				  size_t count, loff_t *ppos)
1567{
1568	int value;
1569	char tmpbuf[TMPBUFLEN];
1570	ssize_t length;
1571	unsigned long i_ino = file_inode(file)->i_ino;
1572
1573	value = security_policycap_supported(i_ino & SEL_INO_MASK);
1574	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1575
1576	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1577}
1578
1579static const struct file_operations sel_policycap_ops = {
1580	.read		= sel_read_policycap,
1581	.llseek		= generic_file_llseek,
1582};
1583
1584static int sel_make_perm_files(char *objclass, int classvalue,
1585				struct dentry *dir)
1586{
1587	int i, rc, nperms;
1588	char **perms;
1589
1590	rc = security_get_permissions(objclass, &perms, &nperms);
1591	if (rc)
1592		return rc;
1593
1594	for (i = 0; i < nperms; i++) {
1595		struct inode *inode;
1596		struct dentry *dentry;
1597
1598		rc = -ENOMEM;
1599		dentry = d_alloc_name(dir, perms[i]);
1600		if (!dentry)
1601			goto out;
1602
1603		rc = -ENOMEM;
1604		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1605		if (!inode)
1606			goto out;
1607
1608		inode->i_fop = &sel_perm_ops;
1609		/* i+1 since perm values are 1-indexed */
1610		inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1611		d_add(dentry, inode);
1612	}
1613	rc = 0;
1614out:
1615	for (i = 0; i < nperms; i++)
1616		kfree(perms[i]);
1617	kfree(perms);
1618	return rc;
1619}
1620
1621static int sel_make_class_dir_entries(char *classname, int index,
1622					struct dentry *dir)
1623{
1624	struct dentry *dentry = NULL;
1625	struct inode *inode = NULL;
1626	int rc;
1627
1628	dentry = d_alloc_name(dir, "index");
1629	if (!dentry)
1630		return -ENOMEM;
1631
1632	inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1633	if (!inode)
1634		return -ENOMEM;
1635
1636	inode->i_fop = &sel_class_ops;
1637	inode->i_ino = sel_class_to_ino(index);
1638	d_add(dentry, inode);
1639
1640	dentry = sel_make_dir(dir, "perms", &last_class_ino);
1641	if (IS_ERR(dentry))
1642		return PTR_ERR(dentry);
1643
1644	rc = sel_make_perm_files(classname, index, dentry);
1645
1646	return rc;
1647}
1648
1649static int sel_make_classes(void)
1650{
1651	int rc, nclasses, i;
1652	char **classes;
1653
1654	/* delete any existing entries */
1655	sel_remove_entries(class_dir);
1656
1657	rc = security_get_classes(&classes, &nclasses);
1658	if (rc)
1659		return rc;
1660
1661	/* +2 since classes are 1-indexed */
1662	last_class_ino = sel_class_to_ino(nclasses + 2);
1663
1664	for (i = 0; i < nclasses; i++) {
1665		struct dentry *class_name_dir;
1666
1667		class_name_dir = sel_make_dir(class_dir, classes[i],
1668				&last_class_ino);
1669		if (IS_ERR(class_name_dir)) {
1670			rc = PTR_ERR(class_name_dir);
1671			goto out;
1672		}
1673
1674		/* i+1 since class values are 1-indexed */
1675		rc = sel_make_class_dir_entries(classes[i], i + 1,
1676				class_name_dir);
1677		if (rc)
1678			goto out;
1679	}
1680	rc = 0;
1681out:
1682	for (i = 0; i < nclasses; i++)
1683		kfree(classes[i]);
1684	kfree(classes);
1685	return rc;
1686}
1687
1688static int sel_make_policycap(void)
1689{
1690	unsigned int iter;
1691	struct dentry *dentry = NULL;
1692	struct inode *inode = NULL;
1693
1694	sel_remove_entries(policycap_dir);
1695
1696	for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1697		if (iter < ARRAY_SIZE(policycap_names))
1698			dentry = d_alloc_name(policycap_dir,
1699					      policycap_names[iter]);
1700		else
1701			dentry = d_alloc_name(policycap_dir, "unknown");
1702
1703		if (dentry == NULL)
1704			return -ENOMEM;
1705
1706		inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1707		if (inode == NULL)
1708			return -ENOMEM;
1709
1710		inode->i_fop = &sel_policycap_ops;
1711		inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1712		d_add(dentry, inode);
1713	}
1714
1715	return 0;
1716}
1717
1718static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1719			unsigned long *ino)
1720{
1721	struct dentry *dentry = d_alloc_name(dir, name);
1722	struct inode *inode;
1723
1724	if (!dentry)
1725		return ERR_PTR(-ENOMEM);
1726
1727	inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1728	if (!inode) {
1729		dput(dentry);
1730		return ERR_PTR(-ENOMEM);
1731	}
1732
1733	inode->i_op = &simple_dir_inode_operations;
1734	inode->i_fop = &simple_dir_operations;
1735	inode->i_ino = ++(*ino);
1736	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1737	inc_nlink(inode);
1738	d_add(dentry, inode);
1739	/* bump link count on parent directory, too */
1740	inc_nlink(d_inode(dir));
1741
1742	return dentry;
1743}
1744
1745static int sel_fill_super(struct super_block *sb, void *data, int silent)
1746{
1747	int ret;
1748	struct dentry *dentry;
1749	struct inode *inode;
1750	struct inode_security_struct *isec;
1751
1752	static struct tree_descr selinux_files[] = {
1753		[SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1754		[SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1755		[SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1756		[SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1757		[SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1758		[SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1759		[SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1760		[SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1761		[SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1762		[SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1763		[SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1764		[SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1765		[SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1766		[SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1767		[SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1768		[SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1769		[SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1770		/* last one */ {""}
1771	};
1772	ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1773	if (ret)
1774		goto err;
1775
1776	bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino);
1777	if (IS_ERR(bool_dir)) {
1778		ret = PTR_ERR(bool_dir);
1779		bool_dir = NULL;
1780		goto err;
1781	}
1782
1783	ret = -ENOMEM;
1784	dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1785	if (!dentry)
1786		goto err;
1787
1788	ret = -ENOMEM;
1789	inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1790	if (!inode)
1791		goto err;
1792
1793	inode->i_ino = ++sel_last_ino;
1794	isec = (struct inode_security_struct *)inode->i_security;
1795	isec->sid = SECINITSID_DEVNULL;
1796	isec->sclass = SECCLASS_CHR_FILE;
1797	isec->initialized = 1;
1798
1799	init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1800	d_add(dentry, inode);
1801	selinux_null.dentry = dentry;
1802
1803	dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino);
1804	if (IS_ERR(dentry)) {
1805		ret = PTR_ERR(dentry);
1806		goto err;
1807	}
1808
1809	ret = sel_make_avc_files(dentry);
1810	if (ret)
1811		goto err;
1812
1813	dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino);
1814	if (IS_ERR(dentry)) {
1815		ret = PTR_ERR(dentry);
1816		goto err;
1817	}
1818
1819	ret = sel_make_initcon_files(dentry);
1820	if (ret)
1821		goto err;
1822
1823	class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino);
1824	if (IS_ERR(class_dir)) {
1825		ret = PTR_ERR(class_dir);
1826		class_dir = NULL;
1827		goto err;
1828	}
1829
1830	policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino);
1831	if (IS_ERR(policycap_dir)) {
1832		ret = PTR_ERR(policycap_dir);
1833		policycap_dir = NULL;
1834		goto err;
1835	}
1836	return 0;
1837err:
1838	printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1839		__func__);
1840	return ret;
1841}
1842
1843static struct dentry *sel_mount(struct file_system_type *fs_type,
1844		      int flags, const char *dev_name, void *data)
1845{
1846	return mount_single(fs_type, flags, data, sel_fill_super);
1847}
1848
1849static struct file_system_type sel_fs_type = {
1850	.name		= "selinuxfs",
1851	.mount		= sel_mount,
1852	.kill_sb	= kill_litter_super,
1853};
1854
1855struct vfsmount *selinuxfs_mount;
1856
1857static int __init init_sel_fs(void)
1858{
1859	int err;
1860
1861	if (!selinux_enabled)
1862		return 0;
1863
1864	err = sysfs_create_mount_point(fs_kobj, "selinux");
1865	if (err)
1866		return err;
1867
1868	err = register_filesystem(&sel_fs_type);
1869	if (err) {
1870		sysfs_remove_mount_point(fs_kobj, "selinux");
1871		return err;
1872	}
1873
1874	selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
1875	if (IS_ERR(selinuxfs_mount)) {
1876		printk(KERN_ERR "selinuxfs:  could not mount!\n");
1877		err = PTR_ERR(selinuxfs_mount);
1878		selinuxfs_mount = NULL;
1879	}
1880
1881	return err;
1882}
1883
1884__initcall(init_sel_fs);
1885
1886#ifdef CONFIG_SECURITY_SELINUX_DISABLE
1887void exit_sel_fs(void)
1888{
1889	sysfs_remove_mount_point(fs_kobj, "selinux");
1890	kern_unmount(selinuxfs_mount);
1891	unregister_filesystem(&sel_fs_type);
1892}
1893#endif
1894