Merge branch 'next' into for-linus
[linux-2.6.git] / security / selinux / selinuxfs.c
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_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
851         }
852         return ret;
853 }
854
855 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
856                              size_t count, loff_t *ppos)
857 {
858         char *page = NULL;
859         ssize_t length;
860         ssize_t ret;
861         int cur_enforcing;
862         struct inode *inode = filep->f_path.dentry->d_inode;
863         unsigned index = inode->i_ino & SEL_INO_MASK;
864         const char *name = filep->f_path.dentry->d_name.name;
865
866         mutex_lock(&sel_mutex);
867
868         if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
869                 ret = -EINVAL;
870                 goto out;
871         }
872
873         if (count > PAGE_SIZE) {
874                 ret = -EINVAL;
875                 goto out;
876         }
877         page = (char *)get_zeroed_page(GFP_KERNEL);
878         if (!page) {
879                 ret = -ENOMEM;
880                 goto out;
881         }
882
883         cur_enforcing = security_get_bool_value(index);
884         if (cur_enforcing < 0) {
885                 ret = cur_enforcing;
886                 goto out;
887         }
888         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
889                           bool_pending_values[index]);
890         ret = simple_read_from_buffer(buf, count, ppos, page, length);
891 out:
892         mutex_unlock(&sel_mutex);
893         if (page)
894                 free_page((unsigned long)page);
895         return ret;
896 }
897
898 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
899                               size_t count, loff_t *ppos)
900 {
901         char *page = NULL;
902         ssize_t length;
903         int new_value;
904         struct inode *inode = filep->f_path.dentry->d_inode;
905         unsigned index = inode->i_ino & SEL_INO_MASK;
906         const char *name = filep->f_path.dentry->d_name.name;
907
908         mutex_lock(&sel_mutex);
909
910         length = task_has_security(current, SECURITY__SETBOOL);
911         if (length)
912                 goto out;
913
914         if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
915                 length = -EINVAL;
916                 goto out;
917         }
918
919         if (count >= PAGE_SIZE) {
920                 length = -ENOMEM;
921                 goto out;
922         }
923
924         if (*ppos != 0) {
925                 /* No partial writes. */
926                 length = -EINVAL;
927                 goto out;
928         }
929         page = (char *)get_zeroed_page(GFP_KERNEL);
930         if (!page) {
931                 length = -ENOMEM;
932                 goto out;
933         }
934
935         length = -EFAULT;
936         if (copy_from_user(page, buf, count))
937                 goto out;
938
939         length = -EINVAL;
940         if (sscanf(page, "%d", &new_value) != 1)
941                 goto out;
942
943         if (new_value)
944                 new_value = 1;
945
946         bool_pending_values[index] = new_value;
947         length = count;
948
949 out:
950         mutex_unlock(&sel_mutex);
951         if (page)
952                 free_page((unsigned long) page);
953         return length;
954 }
955
956 static const struct file_operations sel_bool_ops = {
957         .read           = sel_read_bool,
958         .write          = sel_write_bool,
959 };
960
961 static ssize_t sel_commit_bools_write(struct file *filep,
962                                       const char __user *buf,
963                                       size_t count, loff_t *ppos)
964 {
965         char *page = NULL;
966         ssize_t length;
967         int new_value;
968
969         mutex_lock(&sel_mutex);
970
971         length = task_has_security(current, SECURITY__SETBOOL);
972         if (length)
973                 goto out;
974
975         if (count >= PAGE_SIZE) {
976                 length = -ENOMEM;
977                 goto out;
978         }
979         if (*ppos != 0) {
980                 /* No partial writes. */
981                 goto out;
982         }
983         page = (char *)get_zeroed_page(GFP_KERNEL);
984         if (!page) {
985                 length = -ENOMEM;
986                 goto out;
987         }
988
989         length = -EFAULT;
990         if (copy_from_user(page, buf, count))
991                 goto out;
992
993         length = -EINVAL;
994         if (sscanf(page, "%d", &new_value) != 1)
995                 goto out;
996
997         if (new_value && bool_pending_values)
998                 security_set_bools(bool_num, bool_pending_values);
999
1000         length = count;
1001
1002 out:
1003         mutex_unlock(&sel_mutex);
1004         if (page)
1005                 free_page((unsigned long) page);
1006         return length;
1007 }
1008
1009 static const struct file_operations sel_commit_bools_ops = {
1010         .write          = sel_commit_bools_write,
1011 };
1012
1013 static void sel_remove_entries(struct dentry *de)
1014 {
1015         struct list_head *node;
1016
1017         spin_lock(&dcache_lock);
1018         node = de->d_subdirs.next;
1019         while (node != &de->d_subdirs) {
1020                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1021                 list_del_init(node);
1022
1023                 if (d->d_inode) {
1024                         d = dget_locked(d);
1025                         spin_unlock(&dcache_lock);
1026                         d_delete(d);
1027                         simple_unlink(de->d_inode, d);
1028                         dput(d);
1029                         spin_lock(&dcache_lock);
1030                 }
1031                 node = de->d_subdirs.next;
1032         }
1033
1034         spin_unlock(&dcache_lock);
1035 }
1036
1037 #define BOOL_DIR_NAME "booleans"
1038
1039 static int sel_make_bools(void)
1040 {
1041         int i, ret = 0;
1042         ssize_t len;
1043         struct dentry *dentry = NULL;
1044         struct dentry *dir = bool_dir;
1045         struct inode *inode = NULL;
1046         struct inode_security_struct *isec;
1047         char **names = NULL, *page;
1048         int num;
1049         int *values = NULL;
1050         u32 sid;
1051
1052         /* remove any existing files */
1053         kfree(bool_pending_names);
1054         kfree(bool_pending_values);
1055         bool_pending_names = NULL;
1056         bool_pending_values = NULL;
1057
1058         sel_remove_entries(dir);
1059
1060         page = (char *)get_zeroed_page(GFP_KERNEL);
1061         if (!page)
1062                 return -ENOMEM;
1063
1064         ret = security_get_bools(&num, &names, &values);
1065         if (ret != 0)
1066                 goto out;
1067
1068         for (i = 0; i < num; i++) {
1069                 dentry = d_alloc_name(dir, names[i]);
1070                 if (!dentry) {
1071                         ret = -ENOMEM;
1072                         goto err;
1073                 }
1074                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1075                 if (!inode) {
1076                         ret = -ENOMEM;
1077                         goto err;
1078                 }
1079
1080                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1081                 if (len < 0) {
1082                         ret = -EINVAL;
1083                         goto err;
1084                 } else if (len >= PAGE_SIZE) {
1085                         ret = -ENAMETOOLONG;
1086                         goto err;
1087                 }
1088                 isec = (struct inode_security_struct *)inode->i_security;
1089                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1090                 if (ret)
1091                         goto err;
1092                 isec->sid = sid;
1093                 isec->initialized = 1;
1094                 inode->i_fop = &sel_bool_ops;
1095                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1096                 d_add(dentry, inode);
1097         }
1098         bool_num = num;
1099         bool_pending_names = names;
1100         bool_pending_values = values;
1101 out:
1102         free_page((unsigned long)page);
1103         return ret;
1104 err:
1105         if (names) {
1106                 for (i = 0; i < num; i++)
1107                         kfree(names[i]);
1108                 kfree(names);
1109         }
1110         kfree(values);
1111         sel_remove_entries(dir);
1112         ret = -ENOMEM;
1113         goto out;
1114 }
1115
1116 #define NULL_FILE_NAME "null"
1117
1118 struct dentry *selinux_null;
1119
1120 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1121                                             size_t count, loff_t *ppos)
1122 {
1123         char tmpbuf[TMPBUFLEN];
1124         ssize_t length;
1125
1126         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1127         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1128 }
1129
1130 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1131                                              const char __user *buf,
1132                                              size_t count, loff_t *ppos)
1133
1134 {
1135         char *page;
1136         ssize_t ret;
1137         int new_value;
1138
1139         if (count >= PAGE_SIZE) {
1140                 ret = -ENOMEM;
1141                 goto out;
1142         }
1143
1144         if (*ppos != 0) {
1145                 /* No partial writes. */
1146                 ret = -EINVAL;
1147                 goto out;
1148         }
1149
1150         page = (char *)get_zeroed_page(GFP_KERNEL);
1151         if (!page) {
1152                 ret = -ENOMEM;
1153                 goto out;
1154         }
1155
1156         if (copy_from_user(page, buf, count)) {
1157                 ret = -EFAULT;
1158                 goto out_free;
1159         }
1160
1161         if (sscanf(page, "%u", &new_value) != 1) {
1162                 ret = -EINVAL;
1163                 goto out;
1164         }
1165
1166         if (new_value != avc_cache_threshold) {
1167                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1168                 if (ret)
1169                         goto out_free;
1170                 avc_cache_threshold = new_value;
1171         }
1172         ret = count;
1173 out_free:
1174         free_page((unsigned long)page);
1175 out:
1176         return ret;
1177 }
1178
1179 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1180                                        size_t count, loff_t *ppos)
1181 {
1182         char *page;
1183         ssize_t ret = 0;
1184
1185         page = (char *)__get_free_page(GFP_KERNEL);
1186         if (!page) {
1187                 ret = -ENOMEM;
1188                 goto out;
1189         }
1190         ret = avc_get_hash_stats(page);
1191         if (ret >= 0)
1192                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1193         free_page((unsigned long)page);
1194 out:
1195         return ret;
1196 }
1197
1198 static const struct file_operations sel_avc_cache_threshold_ops = {
1199         .read           = sel_read_avc_cache_threshold,
1200         .write          = sel_write_avc_cache_threshold,
1201 };
1202
1203 static const struct file_operations sel_avc_hash_stats_ops = {
1204         .read           = sel_read_avc_hash_stats,
1205 };
1206
1207 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1208 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1209 {
1210         int cpu;
1211
1212         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1213                 if (!cpu_possible(cpu))
1214                         continue;
1215                 *idx = cpu + 1;
1216                 return &per_cpu(avc_cache_stats, cpu);
1217         }
1218         return NULL;
1219 }
1220
1221 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1222 {
1223         loff_t n = *pos - 1;
1224
1225         if (*pos == 0)
1226                 return SEQ_START_TOKEN;
1227
1228         return sel_avc_get_stat_idx(&n);
1229 }
1230
1231 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1232 {
1233         return sel_avc_get_stat_idx(pos);
1234 }
1235
1236 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1237 {
1238         struct avc_cache_stats *st = v;
1239
1240         if (v == SEQ_START_TOKEN)
1241                 seq_printf(seq, "lookups hits misses allocations reclaims "
1242                            "frees\n");
1243         else
1244                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1245                            st->hits, st->misses, st->allocations,
1246                            st->reclaims, st->frees);
1247         return 0;
1248 }
1249
1250 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1251 { }
1252
1253 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1254         .start          = sel_avc_stats_seq_start,
1255         .next           = sel_avc_stats_seq_next,
1256         .show           = sel_avc_stats_seq_show,
1257         .stop           = sel_avc_stats_seq_stop,
1258 };
1259
1260 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1261 {
1262         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1263 }
1264
1265 static const struct file_operations sel_avc_cache_stats_ops = {
1266         .open           = sel_open_avc_cache_stats,
1267         .read           = seq_read,
1268         .llseek         = seq_lseek,
1269         .release        = seq_release,
1270 };
1271 #endif
1272
1273 static int sel_make_avc_files(struct dentry *dir)
1274 {
1275         int i, ret = 0;
1276         static struct tree_descr files[] = {
1277                 { "cache_threshold",
1278                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1279                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1280 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1281                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1282 #endif
1283         };
1284
1285         for (i = 0; i < ARRAY_SIZE(files); i++) {
1286                 struct inode *inode;
1287                 struct dentry *dentry;
1288
1289                 dentry = d_alloc_name(dir, files[i].name);
1290                 if (!dentry) {
1291                         ret = -ENOMEM;
1292                         goto out;
1293                 }
1294
1295                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1296                 if (!inode) {
1297                         ret = -ENOMEM;
1298                         goto out;
1299                 }
1300                 inode->i_fop = files[i].ops;
1301                 inode->i_ino = ++sel_last_ino;
1302                 d_add(dentry, inode);
1303         }
1304 out:
1305         return ret;
1306 }
1307
1308 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1309                                 size_t count, loff_t *ppos)
1310 {
1311         struct inode *inode;
1312         char *con;
1313         u32 sid, len;
1314         ssize_t ret;
1315
1316         inode = file->f_path.dentry->d_inode;
1317         sid = inode->i_ino&SEL_INO_MASK;
1318         ret = security_sid_to_context(sid, &con, &len);
1319         if (ret < 0)
1320                 return ret;
1321
1322         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1323         kfree(con);
1324         return ret;
1325 }
1326
1327 static const struct file_operations sel_initcon_ops = {
1328         .read           = sel_read_initcon,
1329 };
1330
1331 static int sel_make_initcon_files(struct dentry *dir)
1332 {
1333         int i, ret = 0;
1334
1335         for (i = 1; i <= SECINITSID_NUM; i++) {
1336                 struct inode *inode;
1337                 struct dentry *dentry;
1338                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1339                 if (!dentry) {
1340                         ret = -ENOMEM;
1341                         goto out;
1342                 }
1343
1344                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1345                 if (!inode) {
1346                         ret = -ENOMEM;
1347                         goto out;
1348                 }
1349                 inode->i_fop = &sel_initcon_ops;
1350                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1351                 d_add(dentry, inode);
1352         }
1353 out:
1354         return ret;
1355 }
1356
1357 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1358 {
1359         return a / b - (a % b < 0);
1360 }
1361
1362 static inline unsigned long sel_class_to_ino(u16 class)
1363 {
1364         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1365 }
1366
1367 static inline u16 sel_ino_to_class(unsigned long ino)
1368 {
1369         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1370 }
1371
1372 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1373 {
1374         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1375 }
1376
1377 static inline u32 sel_ino_to_perm(unsigned long ino)
1378 {
1379         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1380 }
1381
1382 static ssize_t sel_read_class(struct file *file, char __user *buf,
1383                                 size_t count, loff_t *ppos)
1384 {
1385         ssize_t rc, len;
1386         char *page;
1387         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1388
1389         page = (char *)__get_free_page(GFP_KERNEL);
1390         if (!page) {
1391                 rc = -ENOMEM;
1392                 goto out;
1393         }
1394
1395         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1396         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1397         free_page((unsigned long)page);
1398 out:
1399         return rc;
1400 }
1401
1402 static const struct file_operations sel_class_ops = {
1403         .read           = sel_read_class,
1404 };
1405
1406 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1407                                 size_t count, loff_t *ppos)
1408 {
1409         ssize_t rc, len;
1410         char *page;
1411         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1412
1413         page = (char *)__get_free_page(GFP_KERNEL);
1414         if (!page) {
1415                 rc = -ENOMEM;
1416                 goto out;
1417         }
1418
1419         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1420         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1421         free_page((unsigned long)page);
1422 out:
1423         return rc;
1424 }
1425
1426 static const struct file_operations sel_perm_ops = {
1427         .read           = sel_read_perm,
1428 };
1429
1430 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1431                                   size_t count, loff_t *ppos)
1432 {
1433         int value;
1434         char tmpbuf[TMPBUFLEN];
1435         ssize_t length;
1436         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1437
1438         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1439         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1440
1441         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1442 }
1443
1444 static const struct file_operations sel_policycap_ops = {
1445         .read           = sel_read_policycap,
1446 };
1447
1448 static int sel_make_perm_files(char *objclass, int classvalue,
1449                                 struct dentry *dir)
1450 {
1451         int i, rc = 0, nperms;
1452         char **perms;
1453
1454         rc = security_get_permissions(objclass, &perms, &nperms);
1455         if (rc)
1456                 goto out;
1457
1458         for (i = 0; i < nperms; i++) {
1459                 struct inode *inode;
1460                 struct dentry *dentry;
1461
1462                 dentry = d_alloc_name(dir, perms[i]);
1463                 if (!dentry) {
1464                         rc = -ENOMEM;
1465                         goto out1;
1466                 }
1467
1468                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1469                 if (!inode) {
1470                         rc = -ENOMEM;
1471                         goto out1;
1472                 }
1473                 inode->i_fop = &sel_perm_ops;
1474                 /* i+1 since perm values are 1-indexed */
1475                 inode->i_ino = sel_perm_to_ino(classvalue, i+1);
1476                 d_add(dentry, inode);
1477         }
1478
1479 out1:
1480         for (i = 0; i < nperms; i++)
1481                 kfree(perms[i]);
1482         kfree(perms);
1483 out:
1484         return rc;
1485 }
1486
1487 static int sel_make_class_dir_entries(char *classname, int index,
1488                                         struct dentry *dir)
1489 {
1490         struct dentry *dentry = NULL;
1491         struct inode *inode = NULL;
1492         int rc;
1493
1494         dentry = d_alloc_name(dir, "index");
1495         if (!dentry) {
1496                 rc = -ENOMEM;
1497                 goto out;
1498         }
1499
1500         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1501         if (!inode) {
1502                 rc = -ENOMEM;
1503                 goto out;
1504         }
1505
1506         inode->i_fop = &sel_class_ops;
1507         inode->i_ino = sel_class_to_ino(index);
1508         d_add(dentry, inode);
1509
1510         dentry = d_alloc_name(dir, "perms");
1511         if (!dentry) {
1512                 rc = -ENOMEM;
1513                 goto out;
1514         }
1515
1516         rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1517         if (rc)
1518                 goto out;
1519
1520         rc = sel_make_perm_files(classname, index, dentry);
1521
1522 out:
1523         return rc;
1524 }
1525
1526 static void sel_remove_classes(void)
1527 {
1528         struct list_head *class_node;
1529
1530         list_for_each(class_node, &class_dir->d_subdirs) {
1531                 struct dentry *class_subdir = list_entry(class_node,
1532                                         struct dentry, d_u.d_child);
1533                 struct list_head *class_subdir_node;
1534
1535                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1536                         struct dentry *d = list_entry(class_subdir_node,
1537                                                 struct dentry, d_u.d_child);
1538
1539                         if (d->d_inode)
1540                                 if (d->d_inode->i_mode & S_IFDIR)
1541                                         sel_remove_entries(d);
1542                 }
1543
1544                 sel_remove_entries(class_subdir);
1545         }
1546
1547         sel_remove_entries(class_dir);
1548 }
1549
1550 static int sel_make_classes(void)
1551 {
1552         int rc = 0, nclasses, i;
1553         char **classes;
1554
1555         /* delete any existing entries */
1556         sel_remove_classes();
1557
1558         rc = security_get_classes(&classes, &nclasses);
1559         if (rc < 0)
1560                 goto out;
1561
1562         /* +2 since classes are 1-indexed */
1563         last_class_ino = sel_class_to_ino(nclasses+2);
1564
1565         for (i = 0; i < nclasses; i++) {
1566                 struct dentry *class_name_dir;
1567
1568                 class_name_dir = d_alloc_name(class_dir, classes[i]);
1569                 if (!class_name_dir) {
1570                         rc = -ENOMEM;
1571                         goto out1;
1572                 }
1573
1574                 rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1575                                 &last_class_ino);
1576                 if (rc)
1577                         goto out1;
1578
1579                 /* i+1 since class values are 1-indexed */
1580                 rc = sel_make_class_dir_entries(classes[i], i+1,
1581                                 class_name_dir);
1582                 if (rc)
1583                         goto out1;
1584         }
1585
1586 out1:
1587         for (i = 0; i < nclasses; i++)
1588                 kfree(classes[i]);
1589         kfree(classes);
1590 out:
1591         return rc;
1592 }
1593
1594 static int sel_make_policycap(void)
1595 {
1596         unsigned int iter;
1597         struct dentry *dentry = NULL;
1598         struct inode *inode = NULL;
1599
1600         sel_remove_entries(policycap_dir);
1601
1602         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1603                 if (iter < ARRAY_SIZE(policycap_names))
1604                         dentry = d_alloc_name(policycap_dir,
1605                                               policycap_names[iter]);
1606                 else
1607                         dentry = d_alloc_name(policycap_dir, "unknown");
1608
1609                 if (dentry == NULL)
1610                         return -ENOMEM;
1611
1612                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1613                 if (inode == NULL)
1614                         return -ENOMEM;
1615
1616                 inode->i_fop = &sel_policycap_ops;
1617                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1618                 d_add(dentry, inode);
1619         }
1620
1621         return 0;
1622 }
1623
1624 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1625                         unsigned long *ino)
1626 {
1627         int ret = 0;
1628         struct inode *inode;
1629
1630         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1631         if (!inode) {
1632                 ret = -ENOMEM;
1633                 goto out;
1634         }
1635         inode->i_op = &simple_dir_inode_operations;
1636         inode->i_fop = &simple_dir_operations;
1637         inode->i_ino = ++(*ino);
1638         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1639         inc_nlink(inode);
1640         d_add(dentry, inode);
1641         /* bump link count on parent directory, too */
1642         inc_nlink(dir);
1643 out:
1644         return ret;
1645 }
1646
1647 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1648 {
1649         int ret;
1650         struct dentry *dentry;
1651         struct inode *inode, *root_inode;
1652         struct inode_security_struct *isec;
1653
1654         static struct tree_descr selinux_files[] = {
1655                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1656                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1657                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1658                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1659                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1660                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1661                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1662                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1663                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1664                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1665                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1666                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1667                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1668                 [SEL_COMPAT_NET] = {"compat_net", &sel_compat_net_ops, S_IRUGO|S_IWUSR},
1669                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1670                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1671                 /* last one */ {""}
1672         };
1673         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1674         if (ret)
1675                 goto err;
1676
1677         root_inode = sb->s_root->d_inode;
1678
1679         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1680         if (!dentry) {
1681                 ret = -ENOMEM;
1682                 goto err;
1683         }
1684
1685         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1686         if (ret)
1687                 goto err;
1688
1689         bool_dir = dentry;
1690
1691         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1692         if (!dentry) {
1693                 ret = -ENOMEM;
1694                 goto err;
1695         }
1696
1697         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1698         if (!inode) {
1699                 ret = -ENOMEM;
1700                 goto err;
1701         }
1702         inode->i_ino = ++sel_last_ino;
1703         isec = (struct inode_security_struct *)inode->i_security;
1704         isec->sid = SECINITSID_DEVNULL;
1705         isec->sclass = SECCLASS_CHR_FILE;
1706         isec->initialized = 1;
1707
1708         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1709         d_add(dentry, inode);
1710         selinux_null = dentry;
1711
1712         dentry = d_alloc_name(sb->s_root, "avc");
1713         if (!dentry) {
1714                 ret = -ENOMEM;
1715                 goto err;
1716         }
1717
1718         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1719         if (ret)
1720                 goto err;
1721
1722         ret = sel_make_avc_files(dentry);
1723         if (ret)
1724                 goto err;
1725
1726         dentry = d_alloc_name(sb->s_root, "initial_contexts");
1727         if (!dentry) {
1728                 ret = -ENOMEM;
1729                 goto err;
1730         }
1731
1732         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1733         if (ret)
1734                 goto err;
1735
1736         ret = sel_make_initcon_files(dentry);
1737         if (ret)
1738                 goto err;
1739
1740         dentry = d_alloc_name(sb->s_root, "class");
1741         if (!dentry) {
1742                 ret = -ENOMEM;
1743                 goto err;
1744         }
1745
1746         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1747         if (ret)
1748                 goto err;
1749
1750         class_dir = dentry;
1751
1752         dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1753         if (!dentry) {
1754                 ret = -ENOMEM;
1755                 goto err;
1756         }
1757
1758         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1759         if (ret)
1760                 goto err;
1761
1762         policycap_dir = dentry;
1763
1764 out:
1765         return ret;
1766 err:
1767         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1768                 __func__);
1769         goto out;
1770 }
1771
1772 static int sel_get_sb(struct file_system_type *fs_type,
1773                       int flags, const char *dev_name, void *data,
1774                       struct vfsmount *mnt)
1775 {
1776         return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
1777 }
1778
1779 static struct file_system_type sel_fs_type = {
1780         .name           = "selinuxfs",
1781         .get_sb         = sel_get_sb,
1782         .kill_sb        = kill_litter_super,
1783 };
1784
1785 struct vfsmount *selinuxfs_mount;
1786
1787 static int __init init_sel_fs(void)
1788 {
1789         int err;
1790
1791         if (!selinux_enabled)
1792                 return 0;
1793         err = register_filesystem(&sel_fs_type);
1794         if (!err) {
1795                 selinuxfs_mount = kern_mount(&sel_fs_type);
1796                 if (IS_ERR(selinuxfs_mount)) {
1797                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1798                         err = PTR_ERR(selinuxfs_mount);
1799                         selinuxfs_mount = NULL;
1800                 }
1801         }
1802         return err;
1803 }
1804
1805 __initcall(init_sel_fs);
1806
1807 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1808 void exit_sel_fs(void)
1809 {
1810         unregister_filesystem(&sel_fs_type);
1811 }
1812 #endif