fde4e9d64bfd34950aa9a40e0143c85507f657b0
[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 #include <linux/kobject.h>
32
33 /* selinuxfs pseudo filesystem for exporting the security policy API.
34    Based on the proc code and the fs/nfsd/nfsctl.c code. */
35
36 #include "flask.h"
37 #include "avc.h"
38 #include "avc_ss.h"
39 #include "security.h"
40 #include "objsec.h"
41 #include "conditional.h"
42
43 /* Policy capability filenames */
44 static char *policycap_names[] = {
45         "network_peer_controls",
46         "open_perms"
47 };
48
49 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
50
51 static int __init checkreqprot_setup(char *str)
52 {
53         unsigned long checkreqprot;
54         if (!strict_strtoul(str, 0, &checkreqprot))
55                 selinux_checkreqprot = checkreqprot ? 1 : 0;
56         return 1;
57 }
58 __setup("checkreqprot=", checkreqprot_setup);
59
60 static DEFINE_MUTEX(sel_mutex);
61
62 /* global data for booleans */
63 static struct dentry *bool_dir;
64 static int bool_num;
65 static char **bool_pending_names;
66 static int *bool_pending_values;
67
68 /* global data for classes */
69 static struct dentry *class_dir;
70 static unsigned long last_class_ino;
71
72 static char policy_opened;
73
74 /* global data for policy capabilities */
75 static struct dentry *policycap_dir;
76
77 extern void selnl_notify_setenforce(int val);
78
79 /* Check whether a task is allowed to use a security operation. */
80 static int task_has_security(struct task_struct *tsk,
81                              u32 perms)
82 {
83         const struct task_security_struct *tsec;
84         u32 sid = 0;
85
86         rcu_read_lock();
87         tsec = __task_cred(tsk)->security;
88         if (tsec)
89                 sid = tsec->sid;
90         rcu_read_unlock();
91         if (!tsec)
92                 return -EACCES;
93
94         return avc_has_perm(sid, SECINITSID_SECURITY,
95                             SECCLASS_SECURITY, perms, NULL);
96 }
97
98 enum sel_inos {
99         SEL_ROOT_INO = 2,
100         SEL_LOAD,       /* load policy */
101         SEL_ENFORCE,    /* get or set enforcing status */
102         SEL_CONTEXT,    /* validate context */
103         SEL_ACCESS,     /* compute access decision */
104         SEL_CREATE,     /* compute create labeling decision */
105         SEL_RELABEL,    /* compute relabeling decision */
106         SEL_USER,       /* compute reachable user contexts */
107         SEL_POLICYVERS, /* return policy version for this kernel */
108         SEL_COMMIT_BOOLS, /* commit new boolean values */
109         SEL_MLS,        /* return if MLS policy is enabled */
110         SEL_DISABLE,    /* disable SELinux until next reboot */
111         SEL_MEMBER,     /* compute polyinstantiation membership decision */
112         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
113         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
114         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
115         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
116         SEL_STATUS,     /* export current status using mmap() */
117         SEL_POLICY,     /* allow userspace to read the in kernel policy */
118         SEL_INO_NEXT,   /* The next inode number to use */
119 };
120
121 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
122
123 #define SEL_INITCON_INO_OFFSET          0x01000000
124 #define SEL_BOOL_INO_OFFSET             0x02000000
125 #define SEL_CLASS_INO_OFFSET            0x04000000
126 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
127 #define SEL_INO_MASK                    0x00ffffff
128
129 #define TMPBUFLEN       12
130 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
131                                 size_t count, loff_t *ppos)
132 {
133         char tmpbuf[TMPBUFLEN];
134         ssize_t length;
135
136         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
137         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
138 }
139
140 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
141 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
142                                  size_t count, loff_t *ppos)
143
144 {
145         char *page = NULL;
146         ssize_t length;
147         int new_value;
148
149         length = -ENOMEM;
150         if (count >= PAGE_SIZE)
151                 goto out;
152
153         /* No partial writes. */
154         length = EINVAL;
155         if (*ppos != 0)
156                 goto out;
157
158         length = -ENOMEM;
159         page = (char *)get_zeroed_page(GFP_KERNEL);
160         if (!page)
161                 goto out;
162
163         length = -EFAULT;
164         if (copy_from_user(page, buf, count))
165                 goto out;
166
167         length = -EINVAL;
168         if (sscanf(page, "%d", &new_value) != 1)
169                 goto out;
170
171         if (new_value != selinux_enforcing) {
172                 length = task_has_security(current, SECURITY__SETENFORCE);
173                 if (length)
174                         goto out;
175                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
176                         "enforcing=%d old_enforcing=%d auid=%u ses=%u",
177                         new_value, selinux_enforcing,
178                         audit_get_loginuid(current),
179                         audit_get_sessionid(current));
180                 selinux_enforcing = new_value;
181                 if (selinux_enforcing)
182                         avc_ss_reset(0);
183                 selnl_notify_setenforce(selinux_enforcing);
184                 selinux_status_update_setenforce(selinux_enforcing);
185         }
186         length = count;
187 out:
188         free_page((unsigned long) page);
189         return length;
190 }
191 #else
192 #define sel_write_enforce NULL
193 #endif
194
195 static const struct file_operations sel_enforce_ops = {
196         .read           = sel_read_enforce,
197         .write          = sel_write_enforce,
198         .llseek         = generic_file_llseek,
199 };
200
201 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
202                                         size_t count, loff_t *ppos)
203 {
204         char tmpbuf[TMPBUFLEN];
205         ssize_t length;
206         ino_t ino = filp->f_path.dentry->d_inode->i_ino;
207         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
208                 security_get_reject_unknown() : !security_get_allow_unknown();
209
210         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
211         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
212 }
213
214 static const struct file_operations sel_handle_unknown_ops = {
215         .read           = sel_read_handle_unknown,
216         .llseek         = generic_file_llseek,
217 };
218
219 static int sel_open_handle_status(struct inode *inode, struct file *filp)
220 {
221         struct page    *status = selinux_kernel_status_page();
222
223         if (!status)
224                 return -ENOMEM;
225
226         filp->private_data = status;
227
228         return 0;
229 }
230
231 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
232                                       size_t count, loff_t *ppos)
233 {
234         struct page    *status = filp->private_data;
235
236         BUG_ON(!status);
237
238         return simple_read_from_buffer(buf, count, ppos,
239                                        page_address(status),
240                                        sizeof(struct selinux_kernel_status));
241 }
242
243 static int sel_mmap_handle_status(struct file *filp,
244                                   struct vm_area_struct *vma)
245 {
246         struct page    *status = filp->private_data;
247         unsigned long   size = vma->vm_end - vma->vm_start;
248
249         BUG_ON(!status);
250
251         /* only allows one page from the head */
252         if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
253                 return -EIO;
254         /* disallow writable mapping */
255         if (vma->vm_flags & VM_WRITE)
256                 return -EPERM;
257         /* disallow mprotect() turns it into writable */
258         vma->vm_flags &= ~VM_MAYWRITE;
259
260         return remap_pfn_range(vma, vma->vm_start,
261                                page_to_pfn(status),
262                                size, vma->vm_page_prot);
263 }
264
265 static const struct file_operations sel_handle_status_ops = {
266         .open           = sel_open_handle_status,
267         .read           = sel_read_handle_status,
268         .mmap           = sel_mmap_handle_status,
269         .llseek         = generic_file_llseek,
270 };
271
272 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
273 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
274                                  size_t count, loff_t *ppos)
275
276 {
277         char *page = NULL;
278         ssize_t length;
279         int new_value;
280         extern int selinux_disable(void);
281
282         length = -ENOMEM;
283         if (count >= PAGE_SIZE)
284                 goto out;;
285
286         /* No partial writes. */
287         length = -EINVAL;
288         if (*ppos != 0)
289                 goto out;
290
291         length = -ENOMEM;
292         page = (char *)get_zeroed_page(GFP_KERNEL);
293         if (!page)
294                 goto out;
295
296         length = -EFAULT;
297         if (copy_from_user(page, buf, count))
298                 goto out;
299
300         length = -EINVAL;
301         if (sscanf(page, "%d", &new_value) != 1)
302                 goto out;
303
304         if (new_value) {
305                 length = selinux_disable();
306                 if (length)
307                         goto out;
308                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
309                         "selinux=0 auid=%u ses=%u",
310                         audit_get_loginuid(current),
311                         audit_get_sessionid(current));
312         }
313
314         length = count;
315 out:
316         free_page((unsigned long) page);
317         return length;
318 }
319 #else
320 #define sel_write_disable NULL
321 #endif
322
323 static const struct file_operations sel_disable_ops = {
324         .write          = sel_write_disable,
325         .llseek         = generic_file_llseek,
326 };
327
328 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
329                                    size_t count, loff_t *ppos)
330 {
331         char tmpbuf[TMPBUFLEN];
332         ssize_t length;
333
334         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
335         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
336 }
337
338 static const struct file_operations sel_policyvers_ops = {
339         .read           = sel_read_policyvers,
340         .llseek         = generic_file_llseek,
341 };
342
343 /* declaration for sel_write_load */
344 static int sel_make_bools(void);
345 static int sel_make_classes(void);
346 static int sel_make_policycap(void);
347
348 /* declaration for sel_make_class_dirs */
349 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
350                         unsigned long *ino);
351
352 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
353                                 size_t count, loff_t *ppos)
354 {
355         char tmpbuf[TMPBUFLEN];
356         ssize_t length;
357
358         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
359                            security_mls_enabled());
360         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
361 }
362
363 static const struct file_operations sel_mls_ops = {
364         .read           = sel_read_mls,
365         .llseek         = generic_file_llseek,
366 };
367
368 struct policy_load_memory {
369         size_t len;
370         void *data;
371 };
372
373 static int sel_open_policy(struct inode *inode, struct file *filp)
374 {
375         struct policy_load_memory *plm = NULL;
376         int rc;
377
378         BUG_ON(filp->private_data);
379
380         mutex_lock(&sel_mutex);
381
382         rc = task_has_security(current, SECURITY__READ_POLICY);
383         if (rc)
384                 goto err;
385
386         rc = -EBUSY;
387         if (policy_opened)
388                 goto err;
389
390         rc = -ENOMEM;
391         plm = kzalloc(sizeof(*plm), GFP_KERNEL);
392         if (!plm)
393                 goto err;
394
395         if (i_size_read(inode) != security_policydb_len()) {
396                 mutex_lock(&inode->i_mutex);
397                 i_size_write(inode, security_policydb_len());
398                 mutex_unlock(&inode->i_mutex);
399         }
400
401         rc = security_read_policy(&plm->data, &plm->len);
402         if (rc)
403                 goto err;
404
405         policy_opened = 1;
406
407         filp->private_data = plm;
408
409         mutex_unlock(&sel_mutex);
410
411         return 0;
412 err:
413         mutex_unlock(&sel_mutex);
414
415         if (plm)
416                 vfree(plm->data);
417         kfree(plm);
418         return rc;
419 }
420
421 static int sel_release_policy(struct inode *inode, struct file *filp)
422 {
423         struct policy_load_memory *plm = filp->private_data;
424
425         BUG_ON(!plm);
426
427         policy_opened = 0;
428
429         vfree(plm->data);
430         kfree(plm);
431
432         return 0;
433 }
434
435 static ssize_t sel_read_policy(struct file *filp, char __user *buf,
436                                size_t count, loff_t *ppos)
437 {
438         struct policy_load_memory *plm = filp->private_data;
439         int ret;
440
441         mutex_lock(&sel_mutex);
442
443         ret = task_has_security(current, SECURITY__READ_POLICY);
444         if (ret)
445                 goto out;
446
447         ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
448 out:
449         mutex_unlock(&sel_mutex);
450         return ret;
451 }
452
453 static int sel_mmap_policy_fault(struct vm_area_struct *vma,
454                                  struct vm_fault *vmf)
455 {
456         struct policy_load_memory *plm = vma->vm_file->private_data;
457         unsigned long offset;
458         struct page *page;
459
460         if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
461                 return VM_FAULT_SIGBUS;
462
463         offset = vmf->pgoff << PAGE_SHIFT;
464         if (offset >= roundup(plm->len, PAGE_SIZE))
465                 return VM_FAULT_SIGBUS;
466
467         page = vmalloc_to_page(plm->data + offset);
468         get_page(page);
469
470         vmf->page = page;
471
472         return 0;
473 }
474
475 static struct vm_operations_struct sel_mmap_policy_ops = {
476         .fault = sel_mmap_policy_fault,
477         .page_mkwrite = sel_mmap_policy_fault,
478 };
479
480 int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
481 {
482         if (vma->vm_flags & VM_SHARED) {
483                 /* do not allow mprotect to make mapping writable */
484                 vma->vm_flags &= ~VM_MAYWRITE;
485
486                 if (vma->vm_flags & VM_WRITE)
487                         return -EACCES;
488         }
489
490         vma->vm_flags |= VM_RESERVED;
491         vma->vm_ops = &sel_mmap_policy_ops;
492
493         return 0;
494 }
495
496 static const struct file_operations sel_policy_ops = {
497         .open           = sel_open_policy,
498         .read           = sel_read_policy,
499         .mmap           = sel_mmap_policy,
500         .release        = sel_release_policy,
501 };
502
503 static ssize_t sel_write_load(struct file *file, const char __user *buf,
504                               size_t count, loff_t *ppos)
505
506 {
507         ssize_t length;
508         void *data = NULL;
509
510         mutex_lock(&sel_mutex);
511
512         length = task_has_security(current, SECURITY__LOAD_POLICY);
513         if (length)
514                 goto out;
515
516         /* No partial writes. */
517         length = -EINVAL;
518         if (*ppos != 0)
519                 goto out;
520
521         length = -EFBIG;
522         if (count > 64 * 1024 * 1024)
523                 goto out;
524
525         length = -ENOMEM;
526         data = vmalloc(count);
527         if (!data)
528                 goto out;
529
530         length = -EFAULT;
531         if (copy_from_user(data, buf, count) != 0)
532                 goto out;
533
534         length = security_load_policy(data, count);
535         if (length)
536                 goto out;
537
538         length = sel_make_bools();
539         if (length)
540                 goto out1;
541
542         length = sel_make_classes();
543         if (length)
544                 goto out1;
545
546         length = sel_make_policycap();
547         if (length)
548                 goto out1;
549
550         length = count;
551
552 out1:
553         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
554                 "policy loaded auid=%u ses=%u",
555                 audit_get_loginuid(current),
556                 audit_get_sessionid(current));
557 out:
558         mutex_unlock(&sel_mutex);
559         vfree(data);
560         return length;
561 }
562
563 static const struct file_operations sel_load_ops = {
564         .write          = sel_write_load,
565         .llseek         = generic_file_llseek,
566 };
567
568 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
569 {
570         char *canon = NULL;
571         u32 sid, len;
572         ssize_t length;
573
574         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
575         if (length)
576                 goto out;
577
578         length = security_context_to_sid(buf, size, &sid);
579         if (length)
580                 goto out;
581
582         length = security_sid_to_context(sid, &canon, &len);
583         if (length)
584                 goto out;
585
586         length = -ERANGE;
587         if (len > SIMPLE_TRANSACTION_LIMIT) {
588                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
589                         "payload max\n", __func__, len);
590                 goto out;
591         }
592
593         memcpy(buf, canon, len);
594         length = len;
595 out:
596         kfree(canon);
597         return length;
598 }
599
600 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
601                                      size_t count, loff_t *ppos)
602 {
603         char tmpbuf[TMPBUFLEN];
604         ssize_t length;
605
606         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
607         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
608 }
609
610 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
611                                       size_t count, loff_t *ppos)
612 {
613         char *page = NULL;
614         ssize_t length;
615         unsigned int new_value;
616
617         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
618         if (length)
619                 goto out;
620
621         length = -ENOMEM;
622         if (count >= PAGE_SIZE)
623                 goto out;
624
625         /* No partial writes. */
626         length = -EINVAL;
627         if (*ppos != 0)
628                 goto out;
629
630         length = -ENOMEM;
631         page = (char *)get_zeroed_page(GFP_KERNEL);
632         if (!page)
633                 goto out;
634
635         length = -EFAULT;
636         if (copy_from_user(page, buf, count))
637                 goto out;
638
639         length = -EINVAL;
640         if (sscanf(page, "%u", &new_value) != 1)
641                 goto out;
642
643         selinux_checkreqprot = new_value ? 1 : 0;
644         length = count;
645 out:
646         free_page((unsigned long) page);
647         return length;
648 }
649 static const struct file_operations sel_checkreqprot_ops = {
650         .read           = sel_read_checkreqprot,
651         .write          = sel_write_checkreqprot,
652         .llseek         = generic_file_llseek,
653 };
654
655 /*
656  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
657  */
658 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
659 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
660 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
661 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
662 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
663
664 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
665         [SEL_ACCESS] = sel_write_access,
666         [SEL_CREATE] = sel_write_create,
667         [SEL_RELABEL] = sel_write_relabel,
668         [SEL_USER] = sel_write_user,
669         [SEL_MEMBER] = sel_write_member,
670         [SEL_CONTEXT] = sel_write_context,
671 };
672
673 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
674 {
675         ino_t ino = file->f_path.dentry->d_inode->i_ino;
676         char *data;
677         ssize_t rv;
678
679         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
680                 return -EINVAL;
681
682         data = simple_transaction_get(file, buf, size);
683         if (IS_ERR(data))
684                 return PTR_ERR(data);
685
686         rv = write_op[ino](file, data, size);
687         if (rv > 0) {
688                 simple_transaction_set(file, rv);
689                 rv = size;
690         }
691         return rv;
692 }
693
694 static const struct file_operations transaction_ops = {
695         .write          = selinux_transaction_write,
696         .read           = simple_transaction_read,
697         .release        = simple_transaction_release,
698         .llseek         = generic_file_llseek,
699 };
700
701 /*
702  * payload - write methods
703  * If the method has a response, the response should be put in buf,
704  * and the length returned.  Otherwise return 0 or and -error.
705  */
706
707 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
708 {
709         char *scon = NULL, *tcon = NULL;
710         u32 ssid, tsid;
711         u16 tclass;
712         struct av_decision avd;
713         ssize_t length;
714
715         length = task_has_security(current, SECURITY__COMPUTE_AV);
716         if (length)
717                 goto out;
718
719         length = -ENOMEM;
720         scon = kzalloc(size + 1, GFP_KERNEL);
721         if (!scon)
722                 goto out;
723
724         length = -ENOMEM;
725         tcon = kzalloc(size + 1, GFP_KERNEL);
726         if (!tcon)
727                 goto out;
728
729         length = -EINVAL;
730         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
731                 goto out;
732
733         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
734         if (length)
735                 goto out;
736
737         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
738         if (length)
739                 goto out;
740
741         security_compute_av_user(ssid, tsid, tclass, &avd);
742
743         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
744                           "%x %x %x %x %u %x",
745                           avd.allowed, 0xffffffff,
746                           avd.auditallow, avd.auditdeny,
747                           avd.seqno, avd.flags);
748 out:
749         kfree(tcon);
750         kfree(scon);
751         return length;
752 }
753
754 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
755 {
756         char *scon = NULL, *tcon = NULL;
757         char *namebuf = NULL, *objname = NULL;
758         u32 ssid, tsid, newsid;
759         u16 tclass;
760         ssize_t length;
761         char *newcon = NULL;
762         u32 len;
763         int nargs;
764
765         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
766         if (length)
767                 goto out;
768
769         length = -ENOMEM;
770         scon = kzalloc(size + 1, GFP_KERNEL);
771         if (!scon)
772                 goto out;
773
774         length = -ENOMEM;
775         tcon = kzalloc(size + 1, GFP_KERNEL);
776         if (!tcon)
777                 goto out;
778
779         length = -ENOMEM;
780         namebuf = kzalloc(size + 1, GFP_KERNEL);
781         if (!namebuf)
782                 goto out;
783
784         length = -EINVAL;
785         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
786         if (nargs < 3 || nargs > 4)
787                 goto out;
788         if (nargs == 4)
789                 objname = namebuf;
790
791         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
792         if (length)
793                 goto out;
794
795         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
796         if (length)
797                 goto out;
798
799         length = security_transition_sid_user(ssid, tsid, tclass,
800                                               objname, &newsid);
801         if (length)
802                 goto out;
803
804         length = security_sid_to_context(newsid, &newcon, &len);
805         if (length)
806                 goto out;
807
808         length = -ERANGE;
809         if (len > SIMPLE_TRANSACTION_LIMIT) {
810                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
811                         "payload max\n", __func__, len);
812                 goto out;
813         }
814
815         memcpy(buf, newcon, len);
816         length = len;
817 out:
818         kfree(newcon);
819         kfree(namebuf);
820         kfree(tcon);
821         kfree(scon);
822         return length;
823 }
824
825 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
826 {
827         char *scon = NULL, *tcon = NULL;
828         u32 ssid, tsid, newsid;
829         u16 tclass;
830         ssize_t length;
831         char *newcon = NULL;
832         u32 len;
833
834         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
835         if (length)
836                 goto out;
837
838         length = -ENOMEM;
839         scon = kzalloc(size + 1, GFP_KERNEL);
840         if (!scon)
841                 goto out;
842
843         length = -ENOMEM;
844         tcon = kzalloc(size + 1, GFP_KERNEL);
845         if (!tcon)
846                 goto out;
847
848         length = -EINVAL;
849         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
850                 goto out;
851
852         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
853         if (length)
854                 goto out;
855
856         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
857         if (length)
858                 goto out;
859
860         length = security_change_sid(ssid, tsid, tclass, &newsid);
861         if (length)
862                 goto out;
863
864         length = security_sid_to_context(newsid, &newcon, &len);
865         if (length)
866                 goto out;
867
868         length = -ERANGE;
869         if (len > SIMPLE_TRANSACTION_LIMIT)
870                 goto out;
871
872         memcpy(buf, newcon, len);
873         length = len;
874 out:
875         kfree(newcon);
876         kfree(tcon);
877         kfree(scon);
878         return length;
879 }
880
881 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
882 {
883         char *con = NULL, *user = NULL, *ptr;
884         u32 sid, *sids = NULL;
885         ssize_t length;
886         char *newcon;
887         int i, rc;
888         u32 len, nsids;
889
890         length = task_has_security(current, SECURITY__COMPUTE_USER);
891         if (length)
892                 goto out;;
893
894         length = -ENOMEM;
895         con = kzalloc(size + 1, GFP_KERNEL);
896         if (!con)
897                 goto out;;
898
899         length = -ENOMEM;
900         user = kzalloc(size + 1, GFP_KERNEL);
901         if (!user)
902                 goto out;
903
904         length = -EINVAL;
905         if (sscanf(buf, "%s %s", con, user) != 2)
906                 goto out;
907
908         length = security_context_to_sid(con, strlen(con) + 1, &sid);
909         if (length)
910                 goto out;
911
912         length = security_get_user_sids(sid, user, &sids, &nsids);
913         if (length)
914                 goto out;
915
916         length = sprintf(buf, "%u", nsids) + 1;
917         ptr = buf + length;
918         for (i = 0; i < nsids; i++) {
919                 rc = security_sid_to_context(sids[i], &newcon, &len);
920                 if (rc) {
921                         length = rc;
922                         goto out;
923                 }
924                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
925                         kfree(newcon);
926                         length = -ERANGE;
927                         goto out;
928                 }
929                 memcpy(ptr, newcon, len);
930                 kfree(newcon);
931                 ptr += len;
932                 length += len;
933         }
934 out:
935         kfree(sids);
936         kfree(user);
937         kfree(con);
938         return length;
939 }
940
941 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
942 {
943         char *scon = NULL, *tcon = NULL;
944         u32 ssid, tsid, newsid;
945         u16 tclass;
946         ssize_t length;
947         char *newcon = NULL;
948         u32 len;
949
950         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
951         if (length)
952                 goto out;
953
954         length = -ENOMEM;
955         scon = kzalloc(size + 1, GFP_KERNEL);
956         if (!scon)
957                 goto out;;
958
959         length = -ENOMEM;
960         tcon = kzalloc(size + 1, GFP_KERNEL);
961         if (!tcon)
962                 goto out;
963
964         length = -EINVAL;
965         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
966                 goto out;
967
968         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
969         if (length)
970                 goto out;
971
972         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
973         if (length)
974                 goto out;
975
976         length = security_member_sid(ssid, tsid, tclass, &newsid);
977         if (length)
978                 goto out;
979
980         length = security_sid_to_context(newsid, &newcon, &len);
981         if (length)
982                 goto out;
983
984         length = -ERANGE;
985         if (len > SIMPLE_TRANSACTION_LIMIT) {
986                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
987                         "payload max\n", __func__, len);
988                 goto out;
989         }
990
991         memcpy(buf, newcon, len);
992         length = len;
993 out:
994         kfree(newcon);
995         kfree(tcon);
996         kfree(scon);
997         return length;
998 }
999
1000 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1001 {
1002         struct inode *ret = new_inode(sb);
1003
1004         if (ret) {
1005                 ret->i_mode = mode;
1006                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
1007         }
1008         return ret;
1009 }
1010
1011 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1012                              size_t count, loff_t *ppos)
1013 {
1014         char *page = NULL;
1015         ssize_t length;
1016         ssize_t ret;
1017         int cur_enforcing;
1018         struct inode *inode = filep->f_path.dentry->d_inode;
1019         unsigned index = inode->i_ino & SEL_INO_MASK;
1020         const char *name = filep->f_path.dentry->d_name.name;
1021
1022         mutex_lock(&sel_mutex);
1023
1024         ret = -EINVAL;
1025         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1026                 goto out;
1027
1028         ret = -ENOMEM;
1029         page = (char *)get_zeroed_page(GFP_KERNEL);
1030         if (!page)
1031                 goto out;
1032
1033         cur_enforcing = security_get_bool_value(index);
1034         if (cur_enforcing < 0) {
1035                 ret = cur_enforcing;
1036                 goto out;
1037         }
1038         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1039                           bool_pending_values[index]);
1040         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1041 out:
1042         mutex_unlock(&sel_mutex);
1043         free_page((unsigned long)page);
1044         return ret;
1045 }
1046
1047 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1048                               size_t count, loff_t *ppos)
1049 {
1050         char *page = NULL;
1051         ssize_t length;
1052         int new_value;
1053         struct inode *inode = filep->f_path.dentry->d_inode;
1054         unsigned index = inode->i_ino & SEL_INO_MASK;
1055         const char *name = filep->f_path.dentry->d_name.name;
1056
1057         mutex_lock(&sel_mutex);
1058
1059         length = task_has_security(current, SECURITY__SETBOOL);
1060         if (length)
1061                 goto out;
1062
1063         length = -EINVAL;
1064         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1065                 goto out;
1066
1067         length = -ENOMEM;
1068         if (count >= PAGE_SIZE)
1069                 goto out;
1070
1071         /* No partial writes. */
1072         length = -EINVAL;
1073         if (*ppos != 0)
1074                 goto out;
1075
1076         length = -ENOMEM;
1077         page = (char *)get_zeroed_page(GFP_KERNEL);
1078         if (!page)
1079                 goto out;
1080
1081         length = -EFAULT;
1082         if (copy_from_user(page, buf, count))
1083                 goto out;
1084
1085         length = -EINVAL;
1086         if (sscanf(page, "%d", &new_value) != 1)
1087                 goto out;
1088
1089         if (new_value)
1090                 new_value = 1;
1091
1092         bool_pending_values[index] = new_value;
1093         length = count;
1094
1095 out:
1096         mutex_unlock(&sel_mutex);
1097         free_page((unsigned long) page);
1098         return length;
1099 }
1100
1101 static const struct file_operations sel_bool_ops = {
1102         .read           = sel_read_bool,
1103         .write          = sel_write_bool,
1104         .llseek         = generic_file_llseek,
1105 };
1106
1107 static ssize_t sel_commit_bools_write(struct file *filep,
1108                                       const char __user *buf,
1109                                       size_t count, loff_t *ppos)
1110 {
1111         char *page = NULL;
1112         ssize_t length;
1113         int new_value;
1114
1115         mutex_lock(&sel_mutex);
1116
1117         length = task_has_security(current, SECURITY__SETBOOL);
1118         if (length)
1119                 goto out;
1120
1121         length = -ENOMEM;
1122         if (count >= PAGE_SIZE)
1123                 goto out;
1124
1125         /* No partial writes. */
1126         length = -EINVAL;
1127         if (*ppos != 0)
1128                 goto out;
1129
1130         length = -ENOMEM;
1131         page = (char *)get_zeroed_page(GFP_KERNEL);
1132         if (!page)
1133                 goto out;
1134
1135         length = -EFAULT;
1136         if (copy_from_user(page, buf, count))
1137                 goto out;
1138
1139         length = -EINVAL;
1140         if (sscanf(page, "%d", &new_value) != 1)
1141                 goto out;
1142
1143         length = 0;
1144         if (new_value && bool_pending_values)
1145                 length = security_set_bools(bool_num, bool_pending_values);
1146
1147         if (!length)
1148                 length = count;
1149
1150 out:
1151         mutex_unlock(&sel_mutex);
1152         free_page((unsigned long) page);
1153         return length;
1154 }
1155
1156 static const struct file_operations sel_commit_bools_ops = {
1157         .write          = sel_commit_bools_write,
1158         .llseek         = generic_file_llseek,
1159 };
1160
1161 static void sel_remove_entries(struct dentry *de)
1162 {
1163         struct list_head *node;
1164
1165         spin_lock(&de->d_lock);
1166         node = de->d_subdirs.next;
1167         while (node != &de->d_subdirs) {
1168                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1169
1170                 spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
1171                 list_del_init(node);
1172
1173                 if (d->d_inode) {
1174                         dget_dlock(d);
1175                         spin_unlock(&de->d_lock);
1176                         spin_unlock(&d->d_lock);
1177                         d_delete(d);
1178                         simple_unlink(de->d_inode, d);
1179                         dput(d);
1180                         spin_lock(&de->d_lock);
1181                 } else
1182                         spin_unlock(&d->d_lock);
1183                 node = de->d_subdirs.next;
1184         }
1185
1186         spin_unlock(&de->d_lock);
1187 }
1188
1189 #define BOOL_DIR_NAME "booleans"
1190
1191 static int sel_make_bools(void)
1192 {
1193         int i, ret;
1194         ssize_t len;
1195         struct dentry *dentry = NULL;
1196         struct dentry *dir = bool_dir;
1197         struct inode *inode = NULL;
1198         struct inode_security_struct *isec;
1199         char **names = NULL, *page;
1200         int num;
1201         int *values = NULL;
1202         u32 sid;
1203
1204         /* remove any existing files */
1205         for (i = 0; i < bool_num; i++)
1206                 kfree(bool_pending_names[i]);
1207         kfree(bool_pending_names);
1208         kfree(bool_pending_values);
1209         bool_pending_names = NULL;
1210         bool_pending_values = NULL;
1211
1212         sel_remove_entries(dir);
1213
1214         ret = -ENOMEM;
1215         page = (char *)get_zeroed_page(GFP_KERNEL);
1216         if (!page)
1217                 goto out;
1218
1219         ret = security_get_bools(&num, &names, &values);
1220         if (ret)
1221                 goto out;
1222
1223         for (i = 0; i < num; i++) {
1224                 ret = -ENOMEM;
1225                 dentry = d_alloc_name(dir, names[i]);
1226                 if (!dentry)
1227                         goto out;
1228
1229                 ret = -ENOMEM;
1230                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1231                 if (!inode)
1232                         goto out;
1233
1234                 ret = -EINVAL;
1235                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1236                 if (len < 0)
1237                         goto out;
1238
1239                 ret = -ENAMETOOLONG;
1240                 if (len >= PAGE_SIZE)
1241                         goto out;
1242
1243                 isec = (struct inode_security_struct *)inode->i_security;
1244                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1245                 if (ret)
1246                         goto out;
1247
1248                 isec->sid = sid;
1249                 isec->initialized = 1;
1250                 inode->i_fop = &sel_bool_ops;
1251                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1252                 d_add(dentry, inode);
1253         }
1254         bool_num = num;
1255         bool_pending_names = names;
1256         bool_pending_values = values;
1257
1258         free_page((unsigned long)page);
1259         return 0;
1260 out:
1261         free_page((unsigned long)page);
1262
1263         if (names) {
1264                 for (i = 0; i < num; i++)
1265                         kfree(names[i]);
1266                 kfree(names);
1267         }
1268         kfree(values);
1269         sel_remove_entries(dir);
1270
1271         return ret;
1272 }
1273
1274 #define NULL_FILE_NAME "null"
1275
1276 struct dentry *selinux_null;
1277
1278 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1279                                             size_t count, loff_t *ppos)
1280 {
1281         char tmpbuf[TMPBUFLEN];
1282         ssize_t length;
1283
1284         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1285         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1286 }
1287
1288 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1289                                              const char __user *buf,
1290                                              size_t count, loff_t *ppos)
1291
1292 {
1293         char *page = NULL;
1294         ssize_t ret;
1295         int new_value;
1296
1297         ret = task_has_security(current, SECURITY__SETSECPARAM);
1298         if (ret)
1299                 goto out;
1300
1301         ret = -ENOMEM;
1302         if (count >= PAGE_SIZE)
1303                 goto out;
1304
1305         /* No partial writes. */
1306         ret = -EINVAL;
1307         if (*ppos != 0)
1308                 goto out;
1309
1310         ret = -ENOMEM;
1311         page = (char *)get_zeroed_page(GFP_KERNEL);
1312         if (!page)
1313                 goto out;
1314
1315         ret = -EFAULT;
1316         if (copy_from_user(page, buf, count))
1317                 goto out;
1318
1319         ret = -EINVAL;
1320         if (sscanf(page, "%u", &new_value) != 1)
1321                 goto out;
1322
1323         avc_cache_threshold = new_value;
1324
1325         ret = count;
1326 out:
1327         free_page((unsigned long)page);
1328         return ret;
1329 }
1330
1331 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1332                                        size_t count, loff_t *ppos)
1333 {
1334         char *page;
1335         ssize_t length;
1336
1337         page = (char *)__get_free_page(GFP_KERNEL);
1338         if (!page)
1339                 return -ENOMEM;
1340
1341         length = avc_get_hash_stats(page);
1342         if (length >= 0)
1343                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1344         free_page((unsigned long)page);
1345
1346         return length;
1347 }
1348
1349 static const struct file_operations sel_avc_cache_threshold_ops = {
1350         .read           = sel_read_avc_cache_threshold,
1351         .write          = sel_write_avc_cache_threshold,
1352         .llseek         = generic_file_llseek,
1353 };
1354
1355 static const struct file_operations sel_avc_hash_stats_ops = {
1356         .read           = sel_read_avc_hash_stats,
1357         .llseek         = generic_file_llseek,
1358 };
1359
1360 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1361 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1362 {
1363         int cpu;
1364
1365         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1366                 if (!cpu_possible(cpu))
1367                         continue;
1368                 *idx = cpu + 1;
1369                 return &per_cpu(avc_cache_stats, cpu);
1370         }
1371         return NULL;
1372 }
1373
1374 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1375 {
1376         loff_t n = *pos - 1;
1377
1378         if (*pos == 0)
1379                 return SEQ_START_TOKEN;
1380
1381         return sel_avc_get_stat_idx(&n);
1382 }
1383
1384 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1385 {
1386         return sel_avc_get_stat_idx(pos);
1387 }
1388
1389 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1390 {
1391         struct avc_cache_stats *st = v;
1392
1393         if (v == SEQ_START_TOKEN)
1394                 seq_printf(seq, "lookups hits misses allocations reclaims "
1395                            "frees\n");
1396         else
1397                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1398                            st->hits, st->misses, st->allocations,
1399                            st->reclaims, st->frees);
1400         return 0;
1401 }
1402
1403 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1404 { }
1405
1406 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1407         .start          = sel_avc_stats_seq_start,
1408         .next           = sel_avc_stats_seq_next,
1409         .show           = sel_avc_stats_seq_show,
1410         .stop           = sel_avc_stats_seq_stop,
1411 };
1412
1413 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1414 {
1415         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1416 }
1417
1418 static const struct file_operations sel_avc_cache_stats_ops = {
1419         .open           = sel_open_avc_cache_stats,
1420         .read           = seq_read,
1421         .llseek         = seq_lseek,
1422         .release        = seq_release,
1423 };
1424 #endif
1425
1426 static int sel_make_avc_files(struct dentry *dir)
1427 {
1428         int i;
1429         static struct tree_descr files[] = {
1430                 { "cache_threshold",
1431                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1432                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1433 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1434                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1435 #endif
1436         };
1437
1438         for (i = 0; i < ARRAY_SIZE(files); i++) {
1439                 struct inode *inode;
1440                 struct dentry *dentry;
1441
1442                 dentry = d_alloc_name(dir, files[i].name);
1443                 if (!dentry)
1444                         return -ENOMEM;
1445
1446                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1447                 if (!inode)
1448                         return -ENOMEM;
1449
1450                 inode->i_fop = files[i].ops;
1451                 inode->i_ino = ++sel_last_ino;
1452                 d_add(dentry, inode);
1453         }
1454
1455         return 0;
1456 }
1457
1458 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1459                                 size_t count, loff_t *ppos)
1460 {
1461         struct inode *inode;
1462         char *con;
1463         u32 sid, len;
1464         ssize_t ret;
1465
1466         inode = file->f_path.dentry->d_inode;
1467         sid = inode->i_ino&SEL_INO_MASK;
1468         ret = security_sid_to_context(sid, &con, &len);
1469         if (ret)
1470                 return ret;
1471
1472         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1473         kfree(con);
1474         return ret;
1475 }
1476
1477 static const struct file_operations sel_initcon_ops = {
1478         .read           = sel_read_initcon,
1479         .llseek         = generic_file_llseek,
1480 };
1481
1482 static int sel_make_initcon_files(struct dentry *dir)
1483 {
1484         int i;
1485
1486         for (i = 1; i <= SECINITSID_NUM; i++) {
1487                 struct inode *inode;
1488                 struct dentry *dentry;
1489                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1490                 if (!dentry)
1491                         return -ENOMEM;
1492
1493                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1494                 if (!inode)
1495                         return -ENOMEM;
1496
1497                 inode->i_fop = &sel_initcon_ops;
1498                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1499                 d_add(dentry, inode);
1500         }
1501
1502         return 0;
1503 }
1504
1505 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1506 {
1507         return a / b - (a % b < 0);
1508 }
1509
1510 static inline unsigned long sel_class_to_ino(u16 class)
1511 {
1512         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1513 }
1514
1515 static inline u16 sel_ino_to_class(unsigned long ino)
1516 {
1517         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1518 }
1519
1520 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1521 {
1522         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1523 }
1524
1525 static inline u32 sel_ino_to_perm(unsigned long ino)
1526 {
1527         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1528 }
1529
1530 static ssize_t sel_read_class(struct file *file, char __user *buf,
1531                                 size_t count, loff_t *ppos)
1532 {
1533         ssize_t rc, len;
1534         char *page;
1535         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1536
1537         page = (char *)__get_free_page(GFP_KERNEL);
1538         if (!page)
1539                 return -ENOMEM;
1540
1541         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1542         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1543         free_page((unsigned long)page);
1544
1545         return rc;
1546 }
1547
1548 static const struct file_operations sel_class_ops = {
1549         .read           = sel_read_class,
1550         .llseek         = generic_file_llseek,
1551 };
1552
1553 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1554                                 size_t count, loff_t *ppos)
1555 {
1556         ssize_t rc, len;
1557         char *page;
1558         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1559
1560         page = (char *)__get_free_page(GFP_KERNEL);
1561         if (!page)
1562                 return -ENOMEM;
1563
1564         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1565         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1566         free_page((unsigned long)page);
1567
1568         return rc;
1569 }
1570
1571 static const struct file_operations sel_perm_ops = {
1572         .read           = sel_read_perm,
1573         .llseek         = generic_file_llseek,
1574 };
1575
1576 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1577                                   size_t count, loff_t *ppos)
1578 {
1579         int value;
1580         char tmpbuf[TMPBUFLEN];
1581         ssize_t length;
1582         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1583
1584         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1585         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1586
1587         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1588 }
1589
1590 static const struct file_operations sel_policycap_ops = {
1591         .read           = sel_read_policycap,
1592         .llseek         = generic_file_llseek,
1593 };
1594
1595 static int sel_make_perm_files(char *objclass, int classvalue,
1596                                 struct dentry *dir)
1597 {
1598         int i, rc, nperms;
1599         char **perms;
1600
1601         rc = security_get_permissions(objclass, &perms, &nperms);
1602         if (rc)
1603                 return rc;
1604
1605         for (i = 0; i < nperms; i++) {
1606                 struct inode *inode;
1607                 struct dentry *dentry;
1608
1609                 rc = -ENOMEM;
1610                 dentry = d_alloc_name(dir, perms[i]);
1611                 if (!dentry)
1612                         goto out;
1613
1614                 rc = -ENOMEM;
1615                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1616                 if (!inode)
1617                         goto out;
1618
1619                 inode->i_fop = &sel_perm_ops;
1620                 /* i+1 since perm values are 1-indexed */
1621                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1622                 d_add(dentry, inode);
1623         }
1624         rc = 0;
1625 out:
1626         for (i = 0; i < nperms; i++)
1627                 kfree(perms[i]);
1628         kfree(perms);
1629         return rc;
1630 }
1631
1632 static int sel_make_class_dir_entries(char *classname, int index,
1633                                         struct dentry *dir)
1634 {
1635         struct dentry *dentry = NULL;
1636         struct inode *inode = NULL;
1637         int rc;
1638
1639         dentry = d_alloc_name(dir, "index");
1640         if (!dentry)
1641                 return -ENOMEM;
1642
1643         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1644         if (!inode)
1645                 return -ENOMEM;
1646
1647         inode->i_fop = &sel_class_ops;
1648         inode->i_ino = sel_class_to_ino(index);
1649         d_add(dentry, inode);
1650
1651         dentry = d_alloc_name(dir, "perms");
1652         if (!dentry)
1653                 return -ENOMEM;
1654
1655         rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1656         if (rc)
1657                 return rc;
1658
1659         rc = sel_make_perm_files(classname, index, dentry);
1660
1661         return rc;
1662 }
1663
1664 static void sel_remove_classes(void)
1665 {
1666         struct list_head *class_node;
1667
1668         list_for_each(class_node, &class_dir->d_subdirs) {
1669                 struct dentry *class_subdir = list_entry(class_node,
1670                                         struct dentry, d_u.d_child);
1671                 struct list_head *class_subdir_node;
1672
1673                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1674                         struct dentry *d = list_entry(class_subdir_node,
1675                                                 struct dentry, d_u.d_child);
1676
1677                         if (d->d_inode)
1678                                 if (d->d_inode->i_mode & S_IFDIR)
1679                                         sel_remove_entries(d);
1680                 }
1681
1682                 sel_remove_entries(class_subdir);
1683         }
1684
1685         sel_remove_entries(class_dir);
1686 }
1687
1688 static int sel_make_classes(void)
1689 {
1690         int rc, nclasses, i;
1691         char **classes;
1692
1693         /* delete any existing entries */
1694         sel_remove_classes();
1695
1696         rc = security_get_classes(&classes, &nclasses);
1697         if (rc)
1698                 return rc;
1699
1700         /* +2 since classes are 1-indexed */
1701         last_class_ino = sel_class_to_ino(nclasses + 2);
1702
1703         for (i = 0; i < nclasses; i++) {
1704                 struct dentry *class_name_dir;
1705
1706                 rc = -ENOMEM;
1707                 class_name_dir = d_alloc_name(class_dir, classes[i]);
1708                 if (!class_name_dir)
1709                         goto out;
1710
1711                 rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1712                                 &last_class_ino);
1713                 if (rc)
1714                         goto out;
1715
1716                 /* i+1 since class values are 1-indexed */
1717                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1718                                 class_name_dir);
1719                 if (rc)
1720                         goto out;
1721         }
1722         rc = 0;
1723 out:
1724         for (i = 0; i < nclasses; i++)
1725                 kfree(classes[i]);
1726         kfree(classes);
1727         return rc;
1728 }
1729
1730 static int sel_make_policycap(void)
1731 {
1732         unsigned int iter;
1733         struct dentry *dentry = NULL;
1734         struct inode *inode = NULL;
1735
1736         sel_remove_entries(policycap_dir);
1737
1738         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1739                 if (iter < ARRAY_SIZE(policycap_names))
1740                         dentry = d_alloc_name(policycap_dir,
1741                                               policycap_names[iter]);
1742                 else
1743                         dentry = d_alloc_name(policycap_dir, "unknown");
1744
1745                 if (dentry == NULL)
1746                         return -ENOMEM;
1747
1748                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1749                 if (inode == NULL)
1750                         return -ENOMEM;
1751
1752                 inode->i_fop = &sel_policycap_ops;
1753                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1754                 d_add(dentry, inode);
1755         }
1756
1757         return 0;
1758 }
1759
1760 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1761                         unsigned long *ino)
1762 {
1763         struct inode *inode;
1764
1765         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1766         if (!inode)
1767                 return -ENOMEM;
1768
1769         inode->i_op = &simple_dir_inode_operations;
1770         inode->i_fop = &simple_dir_operations;
1771         inode->i_ino = ++(*ino);
1772         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1773         inc_nlink(inode);
1774         d_add(dentry, inode);
1775         /* bump link count on parent directory, too */
1776         inc_nlink(dir);
1777
1778         return 0;
1779 }
1780
1781 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1782 {
1783         int ret;
1784         struct dentry *dentry;
1785         struct inode *inode, *root_inode;
1786         struct inode_security_struct *isec;
1787
1788         static struct tree_descr selinux_files[] = {
1789                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1790                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1791                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1792                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1793                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1794                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1795                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1796                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1797                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1798                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1799                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1800                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1801                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1802                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1803                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1804                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1805                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUSR},
1806                 /* last one */ {""}
1807         };
1808         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1809         if (ret)
1810                 goto err;
1811
1812         root_inode = sb->s_root->d_inode;
1813
1814         ret = -ENOMEM;
1815         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1816         if (!dentry)
1817                 goto err;
1818
1819         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1820         if (ret)
1821                 goto err;
1822
1823         bool_dir = dentry;
1824
1825         ret = -ENOMEM;
1826         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1827         if (!dentry)
1828                 goto err;
1829
1830         ret = -ENOMEM;
1831         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1832         if (!inode)
1833                 goto err;
1834
1835         inode->i_ino = ++sel_last_ino;
1836         isec = (struct inode_security_struct *)inode->i_security;
1837         isec->sid = SECINITSID_DEVNULL;
1838         isec->sclass = SECCLASS_CHR_FILE;
1839         isec->initialized = 1;
1840
1841         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1842         d_add(dentry, inode);
1843         selinux_null = dentry;
1844
1845         ret = -ENOMEM;
1846         dentry = d_alloc_name(sb->s_root, "avc");
1847         if (!dentry)
1848                 goto err;
1849
1850         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1851         if (ret)
1852                 goto err;
1853
1854         ret = sel_make_avc_files(dentry);
1855         if (ret)
1856                 goto err;
1857
1858         ret = -ENOMEM;
1859         dentry = d_alloc_name(sb->s_root, "initial_contexts");
1860         if (!dentry)
1861                 goto err;
1862
1863         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1864         if (ret)
1865                 goto err;
1866
1867         ret = sel_make_initcon_files(dentry);
1868         if (ret)
1869                 goto err;
1870
1871         ret = -ENOMEM;
1872         dentry = d_alloc_name(sb->s_root, "class");
1873         if (!dentry)
1874                 goto err;
1875
1876         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1877         if (ret)
1878                 goto err;
1879
1880         class_dir = dentry;
1881
1882         ret = -ENOMEM;
1883         dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1884         if (!dentry)
1885                 goto err;
1886
1887         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1888         if (ret)
1889                 goto err;
1890
1891         policycap_dir = dentry;
1892
1893         return 0;
1894 err:
1895         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1896                 __func__);
1897         return ret;
1898 }
1899
1900 static struct dentry *sel_mount(struct file_system_type *fs_type,
1901                       int flags, const char *dev_name, void *data)
1902 {
1903         return mount_single(fs_type, flags, data, sel_fill_super);
1904 }
1905
1906 static struct file_system_type sel_fs_type = {
1907         .name           = "selinuxfs",
1908         .mount          = sel_mount,
1909         .kill_sb        = kill_litter_super,
1910 };
1911
1912 struct vfsmount *selinuxfs_mount;
1913 static struct kobject *selinuxfs_kobj;
1914
1915 static int __init init_sel_fs(void)
1916 {
1917         int err;
1918
1919         if (!selinux_enabled)
1920                 return 0;
1921
1922         selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj);
1923         if (!selinuxfs_kobj)
1924                 return -ENOMEM;
1925
1926         err = register_filesystem(&sel_fs_type);
1927         if (err) {
1928                 kobject_put(selinuxfs_kobj);
1929                 return err;
1930         }
1931
1932         selinuxfs_mount = kern_mount(&sel_fs_type);
1933         if (IS_ERR(selinuxfs_mount)) {
1934                 printk(KERN_ERR "selinuxfs:  could not mount!\n");
1935                 err = PTR_ERR(selinuxfs_mount);
1936                 selinuxfs_mount = NULL;
1937         }
1938
1939         return err;
1940 }
1941
1942 __initcall(init_sel_fs);
1943
1944 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1945 void exit_sel_fs(void)
1946 {
1947         kobject_put(selinuxfs_kobj);
1948         unregister_filesystem(&sel_fs_type);
1949 }
1950 #endif