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