[PATCH] selinux: ARRAY_SIZE cleanups
[linux-2.6.git] / security / selinux / selinuxfs.c
1 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
2  *
3  *      Added conditional policy language extensions
4  *
5  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
6  * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
7  *      This program is free software; you can redistribute it and/or modify
8  *      it under the terms of the GNU General Public License as published by
9  *      the Free Software Foundation, version 2.
10  */
11
12 #include <linux/config.h>
13 #include <linux/kernel.h>
14 #include <linux/pagemap.h>
15 #include <linux/slab.h>
16 #include <linux/vmalloc.h>
17 #include <linux/fs.h>
18 #include <linux/init.h>
19 #include <linux/string.h>
20 #include <linux/security.h>
21 #include <linux/major.h>
22 #include <linux/seq_file.h>
23 #include <linux/percpu.h>
24 #include <asm/uaccess.h>
25 #include <asm/semaphore.h>
26
27 /* selinuxfs pseudo filesystem for exporting the security policy API.
28    Based on the proc code and the fs/nfsd/nfsctl.c code. */
29
30 #include "flask.h"
31 #include "avc.h"
32 #include "avc_ss.h"
33 #include "security.h"
34 #include "objsec.h"
35 #include "conditional.h"
36
37 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
38
39 static int __init checkreqprot_setup(char *str)
40 {
41         selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0;
42         return 1;
43 }
44 __setup("checkreqprot=", checkreqprot_setup);
45
46
47 static DECLARE_MUTEX(sel_sem);
48
49 /* global data for booleans */
50 static struct dentry *bool_dir = NULL;
51 static int bool_num = 0;
52 static int *bool_pending_values = NULL;
53
54 extern void selnl_notify_setenforce(int val);
55
56 /* Check whether a task is allowed to use a security operation. */
57 static int task_has_security(struct task_struct *tsk,
58                              u32 perms)
59 {
60         struct task_security_struct *tsec;
61
62         tsec = tsk->security;
63         if (!tsec)
64                 return -EACCES;
65
66         return avc_has_perm(tsec->sid, SECINITSID_SECURITY,
67                             SECCLASS_SECURITY, perms, NULL);
68 }
69
70 enum sel_inos {
71         SEL_ROOT_INO = 2,
72         SEL_LOAD,       /* load policy */
73         SEL_ENFORCE,    /* get or set enforcing status */
74         SEL_CONTEXT,    /* validate context */
75         SEL_ACCESS,     /* compute access decision */
76         SEL_CREATE,     /* compute create labeling decision */
77         SEL_RELABEL,    /* compute relabeling decision */
78         SEL_USER,       /* compute reachable user contexts */
79         SEL_POLICYVERS, /* return policy version for this kernel */
80         SEL_COMMIT_BOOLS, /* commit new boolean values */
81         SEL_MLS,        /* return if MLS policy is enabled */
82         SEL_DISABLE,    /* disable SELinux until next reboot */
83         SEL_AVC,        /* AVC management directory */
84         SEL_MEMBER,     /* compute polyinstantiation membership decision */
85         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
86 };
87
88 #define TMPBUFLEN       12
89 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
90                                 size_t count, loff_t *ppos)
91 {
92         char tmpbuf[TMPBUFLEN];
93         ssize_t length;
94
95         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
96         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
97 }
98
99 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
100 static ssize_t sel_write_enforce(struct file * file, const char __user * buf,
101                                  size_t count, loff_t *ppos)
102
103 {
104         char *page;
105         ssize_t length;
106         int new_value;
107
108         if (count >= PAGE_SIZE)
109                 return -ENOMEM;
110         if (*ppos != 0) {
111                 /* No partial writes. */
112                 return -EINVAL;
113         }
114         page = (char*)get_zeroed_page(GFP_KERNEL);
115         if (!page)
116                 return -ENOMEM;
117         length = -EFAULT;
118         if (copy_from_user(page, buf, count))
119                 goto out;
120
121         length = -EINVAL;
122         if (sscanf(page, "%d", &new_value) != 1)
123                 goto out;
124
125         if (new_value != selinux_enforcing) {
126                 length = task_has_security(current, SECURITY__SETENFORCE);
127                 if (length)
128                         goto out;
129                 selinux_enforcing = new_value;
130                 if (selinux_enforcing)
131                         avc_ss_reset(0);
132                 selnl_notify_setenforce(selinux_enforcing);
133         }
134         length = count;
135 out:
136         free_page((unsigned long) page);
137         return length;
138 }
139 #else
140 #define sel_write_enforce NULL
141 #endif
142
143 static struct file_operations sel_enforce_ops = {
144         .read           = sel_read_enforce,
145         .write          = sel_write_enforce,
146 };
147
148 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
149 static ssize_t sel_write_disable(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         extern int selinux_disable(void);
157
158         if (count >= PAGE_SIZE)
159                 return -ENOMEM;
160         if (*ppos != 0) {
161                 /* No partial writes. */
162                 return -EINVAL;
163         }
164         page = (char*)get_zeroed_page(GFP_KERNEL);
165         if (!page)
166                 return -ENOMEM;
167         length = -EFAULT;
168         if (copy_from_user(page, buf, count))
169                 goto out;
170
171         length = -EINVAL;
172         if (sscanf(page, "%d", &new_value) != 1)
173                 goto out;
174
175         if (new_value) {
176                 length = selinux_disable();
177                 if (length < 0)
178                         goto out;
179         }
180
181         length = count;
182 out:
183         free_page((unsigned long) page);
184         return length;
185 }
186 #else
187 #define sel_write_disable NULL
188 #endif
189
190 static struct file_operations sel_disable_ops = {
191         .write          = sel_write_disable,
192 };
193
194 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
195                                    size_t count, loff_t *ppos)
196 {
197         char tmpbuf[TMPBUFLEN];
198         ssize_t length;
199
200         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
201         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
202 }
203
204 static struct file_operations sel_policyvers_ops = {
205         .read           = sel_read_policyvers,
206 };
207
208 /* declaration for sel_write_load */
209 static int sel_make_bools(void);
210
211 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
212                                 size_t count, loff_t *ppos)
213 {
214         char tmpbuf[TMPBUFLEN];
215         ssize_t length;
216
217         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
218         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
219 }
220
221 static struct file_operations sel_mls_ops = {
222         .read           = sel_read_mls,
223 };
224
225 static ssize_t sel_write_load(struct file * file, const char __user * buf,
226                               size_t count, loff_t *ppos)
227
228 {
229         int ret;
230         ssize_t length;
231         void *data = NULL;
232
233         down(&sel_sem);
234
235         length = task_has_security(current, SECURITY__LOAD_POLICY);
236         if (length)
237                 goto out;
238
239         if (*ppos != 0) {
240                 /* No partial writes. */
241                 length = -EINVAL;
242                 goto out;
243         }
244
245         if ((count > 64 * 1024 * 1024)
246             || (data = vmalloc(count)) == NULL) {
247                 length = -ENOMEM;
248                 goto out;
249         }
250
251         length = -EFAULT;
252         if (copy_from_user(data, buf, count) != 0)
253                 goto out;
254
255         length = security_load_policy(data, count);
256         if (length)
257                 goto out;
258
259         ret = sel_make_bools();
260         if (ret)
261                 length = ret;
262         else
263                 length = count;
264 out:
265         up(&sel_sem);
266         vfree(data);
267         return length;
268 }
269
270 static struct file_operations sel_load_ops = {
271         .write          = sel_write_load,
272 };
273
274 static ssize_t sel_write_context(struct file * file, char *buf, size_t size)
275 {
276         char *canon;
277         u32 sid, len;
278         ssize_t length;
279
280         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
281         if (length)
282                 return length;
283
284         length = security_context_to_sid(buf, size, &sid);
285         if (length < 0)
286                 return length;
287
288         length = security_sid_to_context(sid, &canon, &len);
289         if (length < 0)
290                 return length;
291
292         if (len > SIMPLE_TRANSACTION_LIMIT) {
293                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
294                        "max\n", __FUNCTION__, len);
295                 length = -ERANGE;
296                 goto out;
297         }
298
299         memcpy(buf, canon, len);
300         length = len;
301 out:
302         kfree(canon);
303         return length;
304 }
305
306 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
307                                      size_t count, loff_t *ppos)
308 {
309         char tmpbuf[TMPBUFLEN];
310         ssize_t length;
311
312         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
313         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
314 }
315
316 static ssize_t sel_write_checkreqprot(struct file * file, const char __user * buf,
317                                       size_t count, loff_t *ppos)
318 {
319         char *page;
320         ssize_t length;
321         unsigned int new_value;
322
323         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
324         if (length)
325                 return length;
326
327         if (count >= PAGE_SIZE)
328                 return -ENOMEM;
329         if (*ppos != 0) {
330                 /* No partial writes. */
331                 return -EINVAL;
332         }
333         page = (char*)get_zeroed_page(GFP_KERNEL);
334         if (!page)
335                 return -ENOMEM;
336         length = -EFAULT;
337         if (copy_from_user(page, buf, count))
338                 goto out;
339
340         length = -EINVAL;
341         if (sscanf(page, "%u", &new_value) != 1)
342                 goto out;
343
344         selinux_checkreqprot = new_value ? 1 : 0;
345         length = count;
346 out:
347         free_page((unsigned long) page);
348         return length;
349 }
350 static struct file_operations sel_checkreqprot_ops = {
351         .read           = sel_read_checkreqprot,
352         .write          = sel_write_checkreqprot,
353 };
354
355 /*
356  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
357  */
358 static ssize_t sel_write_access(struct file * file, char *buf, size_t size);
359 static ssize_t sel_write_create(struct file * file, char *buf, size_t size);
360 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size);
361 static ssize_t sel_write_user(struct file * file, char *buf, size_t size);
362 static ssize_t sel_write_member(struct file * file, char *buf, size_t size);
363
364 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
365         [SEL_ACCESS] = sel_write_access,
366         [SEL_CREATE] = sel_write_create,
367         [SEL_RELABEL] = sel_write_relabel,
368         [SEL_USER] = sel_write_user,
369         [SEL_MEMBER] = sel_write_member,
370         [SEL_CONTEXT] = sel_write_context,
371 };
372
373 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
374 {
375         ino_t ino =  file->f_dentry->d_inode->i_ino;
376         char *data;
377         ssize_t rv;
378
379         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
380                 return -EINVAL;
381
382         data = simple_transaction_get(file, buf, size);
383         if (IS_ERR(data))
384                 return PTR_ERR(data);
385
386         rv =  write_op[ino](file, data, size);
387         if (rv>0) {
388                 simple_transaction_set(file, rv);
389                 rv = size;
390         }
391         return rv;
392 }
393
394 static struct file_operations transaction_ops = {
395         .write          = selinux_transaction_write,
396         .read           = simple_transaction_read,
397         .release        = simple_transaction_release,
398 };
399
400 /*
401  * payload - write methods
402  * If the method has a response, the response should be put in buf,
403  * and the length returned.  Otherwise return 0 or and -error.
404  */
405
406 static ssize_t sel_write_access(struct file * file, char *buf, size_t size)
407 {
408         char *scon, *tcon;
409         u32 ssid, tsid;
410         u16 tclass;
411         u32 req;
412         struct av_decision avd;
413         ssize_t length;
414
415         length = task_has_security(current, SECURITY__COMPUTE_AV);
416         if (length)
417                 return length;
418
419         length = -ENOMEM;
420         scon = kzalloc(size+1, GFP_KERNEL);
421         if (!scon)
422                 return length;
423
424         tcon = kzalloc(size+1, GFP_KERNEL);
425         if (!tcon)
426                 goto out;
427
428         length = -EINVAL;
429         if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
430                 goto out2;
431
432         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
433         if (length < 0)
434                 goto out2;
435         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
436         if (length < 0)
437                 goto out2;
438
439         length = security_compute_av(ssid, tsid, tclass, req, &avd);
440         if (length < 0)
441                 goto out2;
442
443         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
444                           "%x %x %x %x %u",
445                           avd.allowed, avd.decided,
446                           avd.auditallow, avd.auditdeny,
447                           avd.seqno);
448 out2:
449         kfree(tcon);
450 out:
451         kfree(scon);
452         return length;
453 }
454
455 static ssize_t sel_write_create(struct file * file, char *buf, size_t size)
456 {
457         char *scon, *tcon;
458         u32 ssid, tsid, newsid;
459         u16 tclass;
460         ssize_t length;
461         char *newcon;
462         u32 len;
463
464         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
465         if (length)
466                 return length;
467
468         length = -ENOMEM;
469         scon = kzalloc(size+1, GFP_KERNEL);
470         if (!scon)
471                 return length;
472
473         tcon = kzalloc(size+1, GFP_KERNEL);
474         if (!tcon)
475                 goto out;
476
477         length = -EINVAL;
478         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
479                 goto out2;
480
481         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
482         if (length < 0)
483                 goto out2;
484         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
485         if (length < 0)
486                 goto out2;
487
488         length = security_transition_sid(ssid, tsid, tclass, &newsid);
489         if (length < 0)
490                 goto out2;
491
492         length = security_sid_to_context(newsid, &newcon, &len);
493         if (length < 0)
494                 goto out2;
495
496         if (len > SIMPLE_TRANSACTION_LIMIT) {
497                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
498                        "max\n", __FUNCTION__, len);
499                 length = -ERANGE;
500                 goto out3;
501         }
502
503         memcpy(buf, newcon, len);
504         length = len;
505 out3:
506         kfree(newcon);
507 out2:
508         kfree(tcon);
509 out:
510         kfree(scon);
511         return length;
512 }
513
514 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size)
515 {
516         char *scon, *tcon;
517         u32 ssid, tsid, newsid;
518         u16 tclass;
519         ssize_t length;
520         char *newcon;
521         u32 len;
522
523         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
524         if (length)
525                 return length;
526
527         length = -ENOMEM;
528         scon = kzalloc(size+1, GFP_KERNEL);
529         if (!scon)
530                 return length;
531
532         tcon = kzalloc(size+1, GFP_KERNEL);
533         if (!tcon)
534                 goto out;
535
536         length = -EINVAL;
537         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
538                 goto out2;
539
540         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
541         if (length < 0)
542                 goto out2;
543         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
544         if (length < 0)
545                 goto out2;
546
547         length = security_change_sid(ssid, tsid, tclass, &newsid);
548         if (length < 0)
549                 goto out2;
550
551         length = security_sid_to_context(newsid, &newcon, &len);
552         if (length < 0)
553                 goto out2;
554
555         if (len > SIMPLE_TRANSACTION_LIMIT) {
556                 length = -ERANGE;
557                 goto out3;
558         }
559
560         memcpy(buf, newcon, len);
561         length = len;
562 out3:
563         kfree(newcon);
564 out2:
565         kfree(tcon);
566 out:
567         kfree(scon);
568         return length;
569 }
570
571 static ssize_t sel_write_user(struct file * file, char *buf, size_t size)
572 {
573         char *con, *user, *ptr;
574         u32 sid, *sids;
575         ssize_t length;
576         char *newcon;
577         int i, rc;
578         u32 len, nsids;
579
580         length = task_has_security(current, SECURITY__COMPUTE_USER);
581         if (length)
582                 return length;
583
584         length = -ENOMEM;
585         con = kzalloc(size+1, GFP_KERNEL);
586         if (!con)
587                 return length;
588
589         user = kzalloc(size+1, GFP_KERNEL);
590         if (!user)
591                 goto out;
592
593         length = -EINVAL;
594         if (sscanf(buf, "%s %s", con, user) != 2)
595                 goto out2;
596
597         length = security_context_to_sid(con, strlen(con)+1, &sid);
598         if (length < 0)
599                 goto out2;
600
601         length = security_get_user_sids(sid, user, &sids, &nsids);
602         if (length < 0)
603                 goto out2;
604
605         length = sprintf(buf, "%u", nsids) + 1;
606         ptr = buf + length;
607         for (i = 0; i < nsids; i++) {
608                 rc = security_sid_to_context(sids[i], &newcon, &len);
609                 if (rc) {
610                         length = rc;
611                         goto out3;
612                 }
613                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
614                         kfree(newcon);
615                         length = -ERANGE;
616                         goto out3;
617                 }
618                 memcpy(ptr, newcon, len);
619                 kfree(newcon);
620                 ptr += len;
621                 length += len;
622         }
623 out3:
624         kfree(sids);
625 out2:
626         kfree(user);
627 out:
628         kfree(con);
629         return length;
630 }
631
632 static ssize_t sel_write_member(struct file * file, char *buf, size_t size)
633 {
634         char *scon, *tcon;
635         u32 ssid, tsid, newsid;
636         u16 tclass;
637         ssize_t length;
638         char *newcon;
639         u32 len;
640
641         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
642         if (length)
643                 return length;
644
645         length = -ENOMEM;
646         scon = kzalloc(size+1, GFP_KERNEL);
647         if (!scon)
648                 return length;
649
650         tcon = kzalloc(size+1, GFP_KERNEL);
651         if (!tcon)
652                 goto out;
653
654         length = -EINVAL;
655         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
656                 goto out2;
657
658         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
659         if (length < 0)
660                 goto out2;
661         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
662         if (length < 0)
663                 goto out2;
664
665         length = security_member_sid(ssid, tsid, tclass, &newsid);
666         if (length < 0)
667                 goto out2;
668
669         length = security_sid_to_context(newsid, &newcon, &len);
670         if (length < 0)
671                 goto out2;
672
673         if (len > SIMPLE_TRANSACTION_LIMIT) {
674                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
675                        "max\n", __FUNCTION__, len);
676                 length = -ERANGE;
677                 goto out3;
678         }
679
680         memcpy(buf, newcon, len);
681         length = len;
682 out3:
683         kfree(newcon);
684 out2:
685         kfree(tcon);
686 out:
687         kfree(scon);
688         return length;
689 }
690
691 static struct inode *sel_make_inode(struct super_block *sb, int mode)
692 {
693         struct inode *ret = new_inode(sb);
694
695         if (ret) {
696                 ret->i_mode = mode;
697                 ret->i_uid = ret->i_gid = 0;
698                 ret->i_blksize = PAGE_CACHE_SIZE;
699                 ret->i_blocks = 0;
700                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
701         }
702         return ret;
703 }
704
705 #define BOOL_INO_OFFSET 30
706
707 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
708                              size_t count, loff_t *ppos)
709 {
710         char *page = NULL;
711         ssize_t length;
712         ssize_t end;
713         ssize_t ret;
714         int cur_enforcing;
715         struct inode *inode;
716
717         down(&sel_sem);
718
719         ret = -EFAULT;
720
721         /* check to see if this file has been deleted */
722         if (!filep->f_op)
723                 goto out;
724
725         if (count > PAGE_SIZE) {
726                 ret = -EINVAL;
727                 goto out;
728         }
729         if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) {
730                 ret = -ENOMEM;
731                 goto out;
732         }
733
734         inode = filep->f_dentry->d_inode;
735         cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET);
736         if (cur_enforcing < 0) {
737                 ret = cur_enforcing;
738                 goto out;
739         }
740
741         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
742                           bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]);
743         if (length < 0) {
744                 ret = length;
745                 goto out;
746         }
747
748         if (*ppos >= length) {
749                 ret = 0;
750                 goto out;
751         }
752         if (count + *ppos > length)
753                 count = length - *ppos;
754         end = count + *ppos;
755         if (copy_to_user(buf, (char *) page + *ppos, count)) {
756                 ret = -EFAULT;
757                 goto out;
758         }
759         *ppos = end;
760         ret = count;
761 out:
762         up(&sel_sem);
763         if (page)
764                 free_page((unsigned long)page);
765         return ret;
766 }
767
768 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
769                               size_t count, loff_t *ppos)
770 {
771         char *page = NULL;
772         ssize_t length = -EFAULT;
773         int new_value;
774         struct inode *inode;
775
776         down(&sel_sem);
777
778         length = task_has_security(current, SECURITY__SETBOOL);
779         if (length)
780                 goto out;
781
782         /* check to see if this file has been deleted */
783         if (!filep->f_op)
784                 goto out;
785
786         if (count >= PAGE_SIZE) {
787                 length = -ENOMEM;
788                 goto out;
789         }
790         if (*ppos != 0) {
791                 /* No partial writes. */
792                 goto out;
793         }
794         page = (char*)get_zeroed_page(GFP_KERNEL);
795         if (!page) {
796                 length = -ENOMEM;
797                 goto out;
798         }
799
800         if (copy_from_user(page, buf, count))
801                 goto out;
802
803         length = -EINVAL;
804         if (sscanf(page, "%d", &new_value) != 1)
805                 goto out;
806
807         if (new_value)
808                 new_value = 1;
809
810         inode = filep->f_dentry->d_inode;
811         bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = new_value;
812         length = count;
813
814 out:
815         up(&sel_sem);
816         if (page)
817                 free_page((unsigned long) page);
818         return length;
819 }
820
821 static struct file_operations sel_bool_ops = {
822         .read           = sel_read_bool,
823         .write          = sel_write_bool,
824 };
825
826 static ssize_t sel_commit_bools_write(struct file *filep,
827                                       const char __user *buf,
828                                       size_t count, loff_t *ppos)
829 {
830         char *page = NULL;
831         ssize_t length = -EFAULT;
832         int new_value;
833
834         down(&sel_sem);
835
836         length = task_has_security(current, SECURITY__SETBOOL);
837         if (length)
838                 goto out;
839
840         /* check to see if this file has been deleted */
841         if (!filep->f_op)
842                 goto out;
843
844         if (count >= PAGE_SIZE) {
845                 length = -ENOMEM;
846                 goto out;
847         }
848         if (*ppos != 0) {
849                 /* No partial writes. */
850                 goto out;
851         }
852         page = (char*)get_zeroed_page(GFP_KERNEL);
853         if (!page) {
854                 length = -ENOMEM;
855                 goto out;
856         }
857
858         if (copy_from_user(page, buf, count))
859                 goto out;
860
861         length = -EINVAL;
862         if (sscanf(page, "%d", &new_value) != 1)
863                 goto out;
864
865         if (new_value && bool_pending_values) {
866                 security_set_bools(bool_num, bool_pending_values);
867         }
868
869         length = count;
870
871 out:
872         up(&sel_sem);
873         if (page)
874                 free_page((unsigned long) page);
875         return length;
876 }
877
878 static struct file_operations sel_commit_bools_ops = {
879         .write          = sel_commit_bools_write,
880 };
881
882 /* delete booleans - partial revoke() from
883  * fs/proc/generic.c proc_kill_inodes */
884 static void sel_remove_bools(struct dentry *de)
885 {
886         struct list_head *p, *node;
887         struct super_block *sb = de->d_sb;
888
889         spin_lock(&dcache_lock);
890         node = de->d_subdirs.next;
891         while (node != &de->d_subdirs) {
892                 struct dentry *d = list_entry(node, struct dentry, d_child);
893                 list_del_init(node);
894
895                 if (d->d_inode) {
896                         d = dget_locked(d);
897                         spin_unlock(&dcache_lock);
898                         d_delete(d);
899                         simple_unlink(de->d_inode, d);
900                         dput(d);
901                         spin_lock(&dcache_lock);
902                 }
903                 node = de->d_subdirs.next;
904         }
905
906         spin_unlock(&dcache_lock);
907
908         file_list_lock();
909         list_for_each(p, &sb->s_files) {
910                 struct file * filp = list_entry(p, struct file, f_u.fu_list);
911                 struct dentry * dentry = filp->f_dentry;
912
913                 if (dentry->d_parent != de) {
914                         continue;
915                 }
916                 filp->f_op = NULL;
917         }
918         file_list_unlock();
919 }
920
921 #define BOOL_DIR_NAME "booleans"
922
923 static int sel_make_bools(void)
924 {
925         int i, ret = 0;
926         ssize_t len;
927         struct dentry *dentry = NULL;
928         struct dentry *dir = bool_dir;
929         struct inode *inode = NULL;
930         struct inode_security_struct *isec;
931         char **names = NULL, *page;
932         int num;
933         int *values = NULL;
934         u32 sid;
935
936         /* remove any existing files */
937         kfree(bool_pending_values);
938         bool_pending_values = NULL;
939
940         sel_remove_bools(dir);
941
942         if (!(page = (char*)get_zeroed_page(GFP_KERNEL)))
943                 return -ENOMEM;
944
945         ret = security_get_bools(&num, &names, &values);
946         if (ret != 0)
947                 goto out;
948
949         for (i = 0; i < num; i++) {
950                 dentry = d_alloc_name(dir, names[i]);
951                 if (!dentry) {
952                         ret = -ENOMEM;
953                         goto err;
954                 }
955                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
956                 if (!inode) {
957                         ret = -ENOMEM;
958                         goto err;
959                 }
960
961                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
962                 if (len < 0) {
963                         ret = -EINVAL;
964                         goto err;
965                 } else if (len >= PAGE_SIZE) {
966                         ret = -ENAMETOOLONG;
967                         goto err;
968                 }
969                 isec = (struct inode_security_struct*)inode->i_security;
970                 if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid)))
971                         goto err;
972                 isec->sid = sid;
973                 isec->initialized = 1;
974                 inode->i_fop = &sel_bool_ops;
975                 inode->i_ino = i + BOOL_INO_OFFSET;
976                 d_add(dentry, inode);
977         }
978         bool_num = num;
979         bool_pending_values = values;
980 out:
981         free_page((unsigned long)page);
982         if (names) {
983                 for (i = 0; i < num; i++)
984                         kfree(names[i]);
985                 kfree(names);
986         }
987         return ret;
988 err:
989         kfree(values);
990         d_genocide(dir);
991         ret = -ENOMEM;
992         goto out;
993 }
994
995 #define NULL_FILE_NAME "null"
996
997 struct dentry *selinux_null = NULL;
998
999 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1000                                             size_t count, loff_t *ppos)
1001 {
1002         char tmpbuf[TMPBUFLEN];
1003         ssize_t length;
1004
1005         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1006         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1007 }
1008
1009 static ssize_t sel_write_avc_cache_threshold(struct file * file,
1010                                              const char __user * buf,
1011                                              size_t count, loff_t *ppos)
1012
1013 {
1014         char *page;
1015         ssize_t ret;
1016         int new_value;
1017
1018         if (count >= PAGE_SIZE) {
1019                 ret = -ENOMEM;
1020                 goto out;
1021         }
1022
1023         if (*ppos != 0) {
1024                 /* No partial writes. */
1025                 ret = -EINVAL;
1026                 goto out;
1027         }
1028
1029         page = (char*)get_zeroed_page(GFP_KERNEL);
1030         if (!page) {
1031                 ret = -ENOMEM;
1032                 goto out;
1033         }
1034
1035         if (copy_from_user(page, buf, count)) {
1036                 ret = -EFAULT;
1037                 goto out_free;
1038         }
1039
1040         if (sscanf(page, "%u", &new_value) != 1) {
1041                 ret = -EINVAL;
1042                 goto out;
1043         }
1044
1045         if (new_value != avc_cache_threshold) {
1046                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1047                 if (ret)
1048                         goto out_free;
1049                 avc_cache_threshold = new_value;
1050         }
1051         ret = count;
1052 out_free:
1053         free_page((unsigned long)page);
1054 out:
1055         return ret;
1056 }
1057
1058 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1059                                        size_t count, loff_t *ppos)
1060 {
1061         char *page;
1062         ssize_t ret = 0;
1063
1064         page = (char *)__get_free_page(GFP_KERNEL);
1065         if (!page) {
1066                 ret = -ENOMEM;
1067                 goto out;
1068         }
1069         ret = avc_get_hash_stats(page);
1070         if (ret >= 0)
1071                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1072         free_page((unsigned long)page);
1073 out:
1074         return ret;
1075 }
1076
1077 static struct file_operations sel_avc_cache_threshold_ops = {
1078         .read           = sel_read_avc_cache_threshold,
1079         .write          = sel_write_avc_cache_threshold,
1080 };
1081
1082 static struct file_operations sel_avc_hash_stats_ops = {
1083         .read           = sel_read_avc_hash_stats,
1084 };
1085
1086 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1087 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1088 {
1089         int cpu;
1090
1091         for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1092                 if (!cpu_possible(cpu))
1093                         continue;
1094                 *idx = cpu + 1;
1095                 return &per_cpu(avc_cache_stats, cpu);
1096         }
1097         return NULL;
1098 }
1099
1100 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1101 {
1102         loff_t n = *pos - 1;
1103
1104         if (*pos == 0)
1105                 return SEQ_START_TOKEN;
1106
1107         return sel_avc_get_stat_idx(&n);
1108 }
1109
1110 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1111 {
1112         return sel_avc_get_stat_idx(pos);
1113 }
1114
1115 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1116 {
1117         struct avc_cache_stats *st = v;
1118
1119         if (v == SEQ_START_TOKEN)
1120                 seq_printf(seq, "lookups hits misses allocations reclaims "
1121                            "frees\n");
1122         else
1123                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1124                            st->hits, st->misses, st->allocations,
1125                            st->reclaims, st->frees);
1126         return 0;
1127 }
1128
1129 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1130 { }
1131
1132 static struct seq_operations sel_avc_cache_stats_seq_ops = {
1133         .start          = sel_avc_stats_seq_start,
1134         .next           = sel_avc_stats_seq_next,
1135         .show           = sel_avc_stats_seq_show,
1136         .stop           = sel_avc_stats_seq_stop,
1137 };
1138
1139 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1140 {
1141         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1142 }
1143
1144 static struct file_operations sel_avc_cache_stats_ops = {
1145         .open           = sel_open_avc_cache_stats,
1146         .read           = seq_read,
1147         .llseek         = seq_lseek,
1148         .release        = seq_release,
1149 };
1150 #endif
1151
1152 static int sel_make_avc_files(struct dentry *dir)
1153 {
1154         int i, ret = 0;
1155         static struct tree_descr files[] = {
1156                 { "cache_threshold",
1157                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1158                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1159 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1160                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1161 #endif
1162         };
1163
1164         for (i = 0; i < ARRAY_SIZE(files); i++) {
1165                 struct inode *inode;
1166                 struct dentry *dentry;
1167
1168                 dentry = d_alloc_name(dir, files[i].name);
1169                 if (!dentry) {
1170                         ret = -ENOMEM;
1171                         goto err;
1172                 }
1173
1174                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1175                 if (!inode) {
1176                         ret = -ENOMEM;
1177                         goto err;
1178                 }
1179                 inode->i_fop = files[i].ops;
1180                 d_add(dentry, inode);
1181         }
1182 out:
1183         return ret;
1184 err:
1185         d_genocide(dir);
1186         goto out;
1187 }
1188
1189 static int sel_make_dir(struct super_block *sb, struct dentry *dentry)
1190 {
1191         int ret = 0;
1192         struct inode *inode;
1193
1194         inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1195         if (!inode) {
1196                 ret = -ENOMEM;
1197                 goto out;
1198         }
1199         inode->i_op = &simple_dir_inode_operations;
1200         inode->i_fop = &simple_dir_operations;
1201         d_add(dentry, inode);
1202 out:
1203         return ret;
1204 }
1205
1206 static int sel_fill_super(struct super_block * sb, void * data, int silent)
1207 {
1208         int ret;
1209         struct dentry *dentry;
1210         struct inode *inode;
1211         struct inode_security_struct *isec;
1212
1213         static struct tree_descr selinux_files[] = {
1214                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1215                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1216                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1217                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1218                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1219                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1220                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1221                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1222                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1223                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1224                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1225                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1226                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1227                 /* last one */ {""}
1228         };
1229         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1230         if (ret)
1231                 return ret;
1232
1233         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1234         if (!dentry)
1235                 return -ENOMEM;
1236
1237         inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1238         if (!inode)
1239                 goto out;
1240         inode->i_op = &simple_dir_inode_operations;
1241         inode->i_fop = &simple_dir_operations;
1242         d_add(dentry, inode);
1243         bool_dir = dentry;
1244         ret = sel_make_bools();
1245         if (ret)
1246                 goto out;
1247
1248         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1249         if (!dentry)
1250                 return -ENOMEM;
1251
1252         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1253         if (!inode)
1254                 goto out;
1255         isec = (struct inode_security_struct*)inode->i_security;
1256         isec->sid = SECINITSID_DEVNULL;
1257         isec->sclass = SECCLASS_CHR_FILE;
1258         isec->initialized = 1;
1259
1260         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1261         d_add(dentry, inode);
1262         selinux_null = dentry;
1263
1264         dentry = d_alloc_name(sb->s_root, "avc");
1265         if (!dentry)
1266                 return -ENOMEM;
1267
1268         ret = sel_make_dir(sb, dentry);
1269         if (ret)
1270                 goto out;
1271
1272         ret = sel_make_avc_files(dentry);
1273         if (ret)
1274                 goto out;
1275
1276         return 0;
1277 out:
1278         dput(dentry);
1279         printk(KERN_ERR "%s:  failed while creating inodes\n", __FUNCTION__);
1280         return -ENOMEM;
1281 }
1282
1283 static struct super_block *sel_get_sb(struct file_system_type *fs_type,
1284                                       int flags, const char *dev_name, void *data)
1285 {
1286         return get_sb_single(fs_type, flags, data, sel_fill_super);
1287 }
1288
1289 static struct file_system_type sel_fs_type = {
1290         .name           = "selinuxfs",
1291         .get_sb         = sel_get_sb,
1292         .kill_sb        = kill_litter_super,
1293 };
1294
1295 struct vfsmount *selinuxfs_mount;
1296
1297 static int __init init_sel_fs(void)
1298 {
1299         int err;
1300
1301         if (!selinux_enabled)
1302                 return 0;
1303         err = register_filesystem(&sel_fs_type);
1304         if (!err) {
1305                 selinuxfs_mount = kern_mount(&sel_fs_type);
1306                 if (IS_ERR(selinuxfs_mount)) {
1307                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1308                         err = PTR_ERR(selinuxfs_mount);
1309                         selinuxfs_mount = NULL;
1310                 }
1311         }
1312         return err;
1313 }
1314
1315 __initcall(init_sel_fs);
1316
1317 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1318 void exit_sel_fs(void)
1319 {
1320         unregister_filesystem(&sel_fs_type);
1321 }
1322 #endif