Merge branch 'next-evm' of git://github.com/mzohar/linux-evm into next
[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@paul-moore.com>
6  *
7  *      Added support for the policy capability bitmap
8  *
9  * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
10  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
11  * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
12  *      This program is free software; you can redistribute it and/or modify
13  *      it under the terms of the GNU General Public License as published by
14  *      the Free Software Foundation, version 2.
15  */
16
17 #include <linux/kernel.h>
18 #include <linux/pagemap.h>
19 #include <linux/slab.h>
20 #include <linux/vmalloc.h>
21 #include <linux/fs.h>
22 #include <linux/mutex.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/security.h>
26 #include <linux/major.h>
27 #include <linux/seq_file.h>
28 #include <linux/percpu.h>
29 #include <linux/audit.h>
30 #include <linux/uaccess.h>
31 #include <linux/kobject.h>
32 #include <linux/ctype.h>
33
34 /* selinuxfs pseudo filesystem for exporting the security policy API.
35    Based on the proc code and the fs/nfsd/nfsctl.c code. */
36
37 #include "flask.h"
38 #include "avc.h"
39 #include "avc_ss.h"
40 #include "security.h"
41 #include "objsec.h"
42 #include "conditional.h"
43
44 /* Policy capability filenames */
45 static char *policycap_names[] = {
46         "network_peer_controls",
47         "open_perms"
48 };
49
50 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
51
52 static int __init checkreqprot_setup(char *str)
53 {
54         unsigned long checkreqprot;
55         if (!strict_strtoul(str, 0, &checkreqprot))
56                 selinux_checkreqprot = checkreqprot ? 1 : 0;
57         return 1;
58 }
59 __setup("checkreqprot=", checkreqprot_setup);
60
61 static DEFINE_MUTEX(sel_mutex);
62
63 /* global data for booleans */
64 static struct dentry *bool_dir;
65 static int bool_num;
66 static char **bool_pending_names;
67 static int *bool_pending_values;
68
69 /* global data for classes */
70 static struct dentry *class_dir;
71 static unsigned long last_class_ino;
72
73 static char policy_opened;
74
75 /* global data for policy capabilities */
76 static struct dentry *policycap_dir;
77
78 /* Check whether a task is allowed to use a security operation. */
79 static int task_has_security(struct task_struct *tsk,
80                              u32 perms)
81 {
82         const struct task_security_struct *tsec;
83         u32 sid = 0;
84
85         rcu_read_lock();
86         tsec = __task_cred(tsk)->security;
87         if (tsec)
88                 sid = tsec->sid;
89         rcu_read_unlock();
90         if (!tsec)
91                 return -EACCES;
92
93         return avc_has_perm(sid, SECINITSID_SECURITY,
94                             SECCLASS_SECURITY, perms, NULL);
95 }
96
97 enum sel_inos {
98         SEL_ROOT_INO = 2,
99         SEL_LOAD,       /* load policy */
100         SEL_ENFORCE,    /* get or set enforcing status */
101         SEL_CONTEXT,    /* validate context */
102         SEL_ACCESS,     /* compute access decision */
103         SEL_CREATE,     /* compute create labeling decision */
104         SEL_RELABEL,    /* compute relabeling decision */
105         SEL_USER,       /* compute reachable user contexts */
106         SEL_POLICYVERS, /* return policy version for this kernel */
107         SEL_COMMIT_BOOLS, /* commit new boolean values */
108         SEL_MLS,        /* return if MLS policy is enabled */
109         SEL_DISABLE,    /* disable SELinux until next reboot */
110         SEL_MEMBER,     /* compute polyinstantiation membership decision */
111         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
112         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
113         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
114         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
115         SEL_STATUS,     /* export current status using mmap() */
116         SEL_POLICY,     /* allow userspace to read the in kernel policy */
117         SEL_INO_NEXT,   /* The next inode number to use */
118 };
119
120 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
121
122 #define SEL_INITCON_INO_OFFSET          0x01000000
123 #define SEL_BOOL_INO_OFFSET             0x02000000
124 #define SEL_CLASS_INO_OFFSET            0x04000000
125 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
126 #define SEL_INO_MASK                    0x00ffffff
127
128 #define TMPBUFLEN       12
129 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
130                                 size_t count, loff_t *ppos)
131 {
132         char tmpbuf[TMPBUFLEN];
133         ssize_t length;
134
135         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
136         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
137 }
138
139 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
140 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
141                                  size_t count, loff_t *ppos)
142
143 {
144         char *page = NULL;
145         ssize_t length;
146         int new_value;
147
148         length = -ENOMEM;
149         if (count >= PAGE_SIZE)
150                 goto out;
151
152         /* No partial writes. */
153         length = EINVAL;
154         if (*ppos != 0)
155                 goto out;
156
157         length = -ENOMEM;
158         page = (char *)get_zeroed_page(GFP_KERNEL);
159         if (!page)
160                 goto out;
161
162         length = -EFAULT;
163         if (copy_from_user(page, buf, count))
164                 goto out;
165
166         length = -EINVAL;
167         if (sscanf(page, "%d", &new_value) != 1)
168                 goto out;
169
170         if (new_value != selinux_enforcing) {
171                 length = task_has_security(current, SECURITY__SETENFORCE);
172                 if (length)
173                         goto out;
174                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
175                         "enforcing=%d old_enforcing=%d auid=%u ses=%u",
176                         new_value, selinux_enforcing,
177                         audit_get_loginuid(current),
178                         audit_get_sessionid(current));
179                 selinux_enforcing = new_value;
180                 if (selinux_enforcing)
181                         avc_ss_reset(0);
182                 selnl_notify_setenforce(selinux_enforcing);
183                 selinux_status_update_setenforce(selinux_enforcing);
184         }
185         length = count;
186 out:
187         free_page((unsigned long) page);
188         return length;
189 }
190 #else
191 #define sel_write_enforce NULL
192 #endif
193
194 static const struct file_operations sel_enforce_ops = {
195         .read           = sel_read_enforce,
196         .write          = sel_write_enforce,
197         .llseek         = generic_file_llseek,
198 };
199
200 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
201                                         size_t count, loff_t *ppos)
202 {
203         char tmpbuf[TMPBUFLEN];
204         ssize_t length;
205         ino_t ino = filp->f_path.dentry->d_inode->i_ino;
206         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
207                 security_get_reject_unknown() : !security_get_allow_unknown();
208
209         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
210         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
211 }
212
213 static const struct file_operations sel_handle_unknown_ops = {
214         .read           = sel_read_handle_unknown,
215         .llseek         = generic_file_llseek,
216 };
217
218 static int sel_open_handle_status(struct inode *inode, struct file *filp)
219 {
220         struct page    *status = selinux_kernel_status_page();
221
222         if (!status)
223                 return -ENOMEM;
224
225         filp->private_data = status;
226
227         return 0;
228 }
229
230 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
231                                       size_t count, loff_t *ppos)
232 {
233         struct page    *status = filp->private_data;
234
235         BUG_ON(!status);
236
237         return simple_read_from_buffer(buf, count, ppos,
238                                        page_address(status),
239                                        sizeof(struct selinux_kernel_status));
240 }
241
242 static int sel_mmap_handle_status(struct file *filp,
243                                   struct vm_area_struct *vma)
244 {
245         struct page    *status = filp->private_data;
246         unsigned long   size = vma->vm_end - vma->vm_start;
247
248         BUG_ON(!status);
249
250         /* only allows one page from the head */
251         if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
252                 return -EIO;
253         /* disallow writable mapping */
254         if (vma->vm_flags & VM_WRITE)
255                 return -EPERM;
256         /* disallow mprotect() turns it into writable */
257         vma->vm_flags &= ~VM_MAYWRITE;
258
259         return remap_pfn_range(vma, vma->vm_start,
260                                page_to_pfn(status),
261                                size, vma->vm_page_prot);
262 }
263
264 static const struct file_operations sel_handle_status_ops = {
265         .open           = sel_open_handle_status,
266         .read           = sel_read_handle_status,
267         .mmap           = sel_mmap_handle_status,
268         .llseek         = generic_file_llseek,
269 };
270
271 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
272 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
273                                  size_t count, loff_t *ppos)
274
275 {
276         char *page = NULL;
277         ssize_t length;
278         int new_value;
279
280         length = -ENOMEM;
281         if (count >= PAGE_SIZE)
282                 goto out;
283
284         /* No partial writes. */
285         length = -EINVAL;
286         if (*ppos != 0)
287                 goto out;
288
289         length = -ENOMEM;
290         page = (char *)get_zeroed_page(GFP_KERNEL);
291         if (!page)
292                 goto out;
293
294         length = -EFAULT;
295         if (copy_from_user(page, buf, count))
296                 goto out;
297
298         length = -EINVAL;
299         if (sscanf(page, "%d", &new_value) != 1)
300                 goto out;
301
302         if (new_value) {
303                 length = selinux_disable();
304                 if (length)
305                         goto out;
306                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
307                         "selinux=0 auid=%u ses=%u",
308                         audit_get_loginuid(current),
309                         audit_get_sessionid(current));
310         }
311
312         length = count;
313 out:
314         free_page((unsigned long) page);
315         return length;
316 }
317 #else
318 #define sel_write_disable NULL
319 #endif
320
321 static const struct file_operations sel_disable_ops = {
322         .write          = sel_write_disable,
323         .llseek         = generic_file_llseek,
324 };
325
326 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
327                                    size_t count, loff_t *ppos)
328 {
329         char tmpbuf[TMPBUFLEN];
330         ssize_t length;
331
332         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
333         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
334 }
335
336 static const struct file_operations sel_policyvers_ops = {
337         .read           = sel_read_policyvers,
338         .llseek         = generic_file_llseek,
339 };
340
341 /* declaration for sel_write_load */
342 static int sel_make_bools(void);
343 static int sel_make_classes(void);
344 static int sel_make_policycap(void);
345
346 /* declaration for sel_make_class_dirs */
347 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
348                         unsigned long *ino);
349
350 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
351                                 size_t count, loff_t *ppos)
352 {
353         char tmpbuf[TMPBUFLEN];
354         ssize_t length;
355
356         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
357                            security_mls_enabled());
358         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
359 }
360
361 static const struct file_operations sel_mls_ops = {
362         .read           = sel_read_mls,
363         .llseek         = generic_file_llseek,
364 };
365
366 struct policy_load_memory {
367         size_t len;
368         void *data;
369 };
370
371 static int sel_open_policy(struct inode *inode, struct file *filp)
372 {
373         struct policy_load_memory *plm = NULL;
374         int rc;
375
376         BUG_ON(filp->private_data);
377
378         mutex_lock(&sel_mutex);
379
380         rc = task_has_security(current, SECURITY__READ_POLICY);
381         if (rc)
382                 goto err;
383
384         rc = -EBUSY;
385         if (policy_opened)
386                 goto err;
387
388         rc = -ENOMEM;
389         plm = kzalloc(sizeof(*plm), GFP_KERNEL);
390         if (!plm)
391                 goto err;
392
393         if (i_size_read(inode) != security_policydb_len()) {
394                 mutex_lock(&inode->i_mutex);
395                 i_size_write(inode, security_policydb_len());
396                 mutex_unlock(&inode->i_mutex);
397         }
398
399         rc = security_read_policy(&plm->data, &plm->len);
400         if (rc)
401                 goto err;
402
403         policy_opened = 1;
404
405         filp->private_data = plm;
406
407         mutex_unlock(&sel_mutex);
408
409         return 0;
410 err:
411         mutex_unlock(&sel_mutex);
412
413         if (plm)
414                 vfree(plm->data);
415         kfree(plm);
416         return rc;
417 }
418
419 static int sel_release_policy(struct inode *inode, struct file *filp)
420 {
421         struct policy_load_memory *plm = filp->private_data;
422
423         BUG_ON(!plm);
424
425         policy_opened = 0;
426
427         vfree(plm->data);
428         kfree(plm);
429
430         return 0;
431 }
432
433 static ssize_t sel_read_policy(struct file *filp, char __user *buf,
434                                size_t count, loff_t *ppos)
435 {
436         struct policy_load_memory *plm = filp->private_data;
437         int ret;
438
439         mutex_lock(&sel_mutex);
440
441         ret = task_has_security(current, SECURITY__READ_POLICY);
442         if (ret)
443                 goto out;
444
445         ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
446 out:
447         mutex_unlock(&sel_mutex);
448         return ret;
449 }
450
451 static int sel_mmap_policy_fault(struct vm_area_struct *vma,
452                                  struct vm_fault *vmf)
453 {
454         struct policy_load_memory *plm = vma->vm_file->private_data;
455         unsigned long offset;
456         struct page *page;
457
458         if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
459                 return VM_FAULT_SIGBUS;
460
461         offset = vmf->pgoff << PAGE_SHIFT;
462         if (offset >= roundup(plm->len, PAGE_SIZE))
463                 return VM_FAULT_SIGBUS;
464
465         page = vmalloc_to_page(plm->data + offset);
466         get_page(page);
467
468         vmf->page = page;
469
470         return 0;
471 }
472
473 static struct vm_operations_struct sel_mmap_policy_ops = {
474         .fault = sel_mmap_policy_fault,
475         .page_mkwrite = sel_mmap_policy_fault,
476 };
477
478 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
479 {
480         if (vma->vm_flags & VM_SHARED) {
481                 /* do not allow mprotect to make mapping writable */
482                 vma->vm_flags &= ~VM_MAYWRITE;
483
484                 if (vma->vm_flags & VM_WRITE)
485                         return -EACCES;
486         }
487
488         vma->vm_flags |= VM_RESERVED;
489         vma->vm_ops = &sel_mmap_policy_ops;
490
491         return 0;
492 }
493
494 static const struct file_operations sel_policy_ops = {
495         .open           = sel_open_policy,
496         .read           = sel_read_policy,
497         .mmap           = sel_mmap_policy,
498         .release        = sel_release_policy,
499 };
500
501 static ssize_t sel_write_load(struct file *file, const char __user *buf,
502                               size_t count, loff_t *ppos)
503
504 {
505         ssize_t length;
506         void *data = NULL;
507
508         mutex_lock(&sel_mutex);
509
510         length = task_has_security(current, SECURITY__LOAD_POLICY);
511         if (length)
512                 goto out;
513
514         /* No partial writes. */
515         length = -EINVAL;
516         if (*ppos != 0)
517                 goto out;
518
519         length = -EFBIG;
520         if (count > 64 * 1024 * 1024)
521                 goto out;
522
523         length = -ENOMEM;
524         data = vmalloc(count);
525         if (!data)
526                 goto out;
527
528         length = -EFAULT;
529         if (copy_from_user(data, buf, count) != 0)
530                 goto out;
531
532         length = security_load_policy(data, count);
533         if (length)
534                 goto out;
535
536         length = sel_make_bools();
537         if (length)
538                 goto out1;
539
540         length = sel_make_classes();
541         if (length)
542                 goto out1;
543
544         length = sel_make_policycap();
545         if (length)
546                 goto out1;
547
548         length = count;
549
550 out1:
551         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
552                 "policy loaded auid=%u ses=%u",
553                 audit_get_loginuid(current),
554                 audit_get_sessionid(current));
555 out:
556         mutex_unlock(&sel_mutex);
557         vfree(data);
558         return length;
559 }
560
561 static const struct file_operations sel_load_ops = {
562         .write          = sel_write_load,
563         .llseek         = generic_file_llseek,
564 };
565
566 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
567 {
568         char *canon = NULL;
569         u32 sid, len;
570         ssize_t length;
571
572         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
573         if (length)
574                 goto out;
575
576         length = security_context_to_sid(buf, size, &sid);
577         if (length)
578                 goto out;
579
580         length = security_sid_to_context(sid, &canon, &len);
581         if (length)
582                 goto out;
583
584         length = -ERANGE;
585         if (len > SIMPLE_TRANSACTION_LIMIT) {
586                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
587                         "payload max\n", __func__, len);
588                 goto out;
589         }
590
591         memcpy(buf, canon, len);
592         length = len;
593 out:
594         kfree(canon);
595         return length;
596 }
597
598 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
599                                      size_t count, loff_t *ppos)
600 {
601         char tmpbuf[TMPBUFLEN];
602         ssize_t length;
603
604         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
605         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
606 }
607
608 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
609                                       size_t count, loff_t *ppos)
610 {
611         char *page = NULL;
612         ssize_t length;
613         unsigned int new_value;
614
615         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
616         if (length)
617                 goto out;
618
619         length = -ENOMEM;
620         if (count >= PAGE_SIZE)
621                 goto out;
622
623         /* No partial writes. */
624         length = -EINVAL;
625         if (*ppos != 0)
626                 goto out;
627
628         length = -ENOMEM;
629         page = (char *)get_zeroed_page(GFP_KERNEL);
630         if (!page)
631                 goto out;
632
633         length = -EFAULT;
634         if (copy_from_user(page, buf, count))
635                 goto out;
636
637         length = -EINVAL;
638         if (sscanf(page, "%u", &new_value) != 1)
639                 goto out;
640
641         selinux_checkreqprot = new_value ? 1 : 0;
642         length = count;
643 out:
644         free_page((unsigned long) page);
645         return length;
646 }
647 static const struct file_operations sel_checkreqprot_ops = {
648         .read           = sel_read_checkreqprot,
649         .write          = sel_write_checkreqprot,
650         .llseek         = generic_file_llseek,
651 };
652
653 /*
654  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
655  */
656 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
657 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
658 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
659 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
660 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
661
662 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
663         [SEL_ACCESS] = sel_write_access,
664         [SEL_CREATE] = sel_write_create,
665         [SEL_RELABEL] = sel_write_relabel,
666         [SEL_USER] = sel_write_user,
667         [SEL_MEMBER] = sel_write_member,
668         [SEL_CONTEXT] = sel_write_context,
669 };
670
671 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
672 {
673         ino_t ino = file->f_path.dentry->d_inode->i_ino;
674         char *data;
675         ssize_t rv;
676
677         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
678                 return -EINVAL;
679
680         data = simple_transaction_get(file, buf, size);
681         if (IS_ERR(data))
682                 return PTR_ERR(data);
683
684         rv = write_op[ino](file, data, size);
685         if (rv > 0) {
686                 simple_transaction_set(file, rv);
687                 rv = size;
688         }
689         return rv;
690 }
691
692 static const struct file_operations transaction_ops = {
693         .write          = selinux_transaction_write,
694         .read           = simple_transaction_read,
695         .release        = simple_transaction_release,
696         .llseek         = generic_file_llseek,
697 };
698
699 /*
700  * payload - write methods
701  * If the method has a response, the response should be put in buf,
702  * and the length returned.  Otherwise return 0 or and -error.
703  */
704
705 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
706 {
707         char *scon = NULL, *tcon = NULL;
708         u32 ssid, tsid;
709         u16 tclass;
710         struct av_decision avd;
711         ssize_t length;
712
713         length = task_has_security(current, SECURITY__COMPUTE_AV);
714         if (length)
715                 goto out;
716
717         length = -ENOMEM;
718         scon = kzalloc(size + 1, GFP_KERNEL);
719         if (!scon)
720                 goto out;
721
722         length = -ENOMEM;
723         tcon = kzalloc(size + 1, GFP_KERNEL);
724         if (!tcon)
725                 goto out;
726
727         length = -EINVAL;
728         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
729                 goto out;
730
731         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
732         if (length)
733                 goto out;
734
735         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
736         if (length)
737                 goto out;
738
739         security_compute_av_user(ssid, tsid, tclass, &avd);
740
741         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
742                           "%x %x %x %x %u %x",
743                           avd.allowed, 0xffffffff,
744                           avd.auditallow, avd.auditdeny,
745                           avd.seqno, avd.flags);
746 out:
747         kfree(tcon);
748         kfree(scon);
749         return length;
750 }
751
752 static inline int hexcode_to_int(int code) {
753         if (code == '\0' || !isxdigit(code))
754                 return -1;
755         if (isdigit(code))
756                 return code - '0';
757         return tolower(code) - 'a' + 10;
758 }
759
760 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
761 {
762         char *scon = NULL, *tcon = NULL;
763         char *namebuf = NULL, *objname = NULL;
764         u32 ssid, tsid, newsid;
765         u16 tclass;
766         ssize_t length;
767         char *newcon = NULL;
768         u32 len;
769         int nargs;
770
771         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
772         if (length)
773                 goto out;
774
775         length = -ENOMEM;
776         scon = kzalloc(size + 1, GFP_KERNEL);
777         if (!scon)
778                 goto out;
779
780         length = -ENOMEM;
781         tcon = kzalloc(size + 1, GFP_KERNEL);
782         if (!tcon)
783                 goto out;
784
785         length = -ENOMEM;
786         namebuf = kzalloc(size + 1, GFP_KERNEL);
787         if (!namebuf)
788                 goto out;
789
790         length = -EINVAL;
791         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
792         if (nargs < 3 || nargs > 4)
793                 goto out;
794         if (nargs == 4) {
795                 /*
796                  * If and when the name of new object to be queried contains
797                  * either whitespace or multibyte characters, they shall be
798                  * encoded based on the percentage-encoding rule.
799                  * If not encoded, the sscanf logic picks up only left-half
800                  * of the supplied name; splitted by a whitespace unexpectedly.
801                  */
802                 char   *r, *w;
803                 int     c1, c2;
804
805                 r = w = namebuf;
806                 do {
807                         c1 = *r++;
808                         if (c1 == '+')
809                                 c1 = ' ';
810                         else if (c1 == '%') {
811                                 if ((c1 = hexcode_to_int(*r++)) < 0)
812                                         goto out;
813                                 if ((c2 = hexcode_to_int(*r++)) < 0)
814                                         goto out;
815                                 c1 = (c1 << 4) | c2;
816                         }
817                         *w++ = c1;
818                 } while (c1 != '\0');
819
820                 objname = namebuf;
821         }
822
823         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
824         if (length)
825                 goto out;
826
827         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
828         if (length)
829                 goto out;
830
831         length = security_transition_sid_user(ssid, tsid, tclass,
832                                               objname, &newsid);
833         if (length)
834                 goto out;
835
836         length = security_sid_to_context(newsid, &newcon, &len);
837         if (length)
838                 goto out;
839
840         length = -ERANGE;
841         if (len > SIMPLE_TRANSACTION_LIMIT) {
842                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
843                         "payload max\n", __func__, len);
844                 goto out;
845         }
846
847         memcpy(buf, newcon, len);
848         length = len;
849 out:
850         kfree(newcon);
851         kfree(namebuf);
852         kfree(tcon);
853         kfree(scon);
854         return length;
855 }
856
857 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
858 {
859         char *scon = NULL, *tcon = NULL;
860         u32 ssid, tsid, newsid;
861         u16 tclass;
862         ssize_t length;
863         char *newcon = NULL;
864         u32 len;
865
866         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
867         if (length)
868                 goto out;
869
870         length = -ENOMEM;
871         scon = kzalloc(size + 1, GFP_KERNEL);
872         if (!scon)
873                 goto out;
874
875         length = -ENOMEM;
876         tcon = kzalloc(size + 1, GFP_KERNEL);
877         if (!tcon)
878                 goto out;
879
880         length = -EINVAL;
881         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
882                 goto out;
883
884         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
885         if (length)
886                 goto out;
887
888         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
889         if (length)
890                 goto out;
891
892         length = security_change_sid(ssid, tsid, tclass, &newsid);
893         if (length)
894                 goto out;
895
896         length = security_sid_to_context(newsid, &newcon, &len);
897         if (length)
898                 goto out;
899
900         length = -ERANGE;
901         if (len > SIMPLE_TRANSACTION_LIMIT)
902                 goto out;
903
904         memcpy(buf, newcon, len);
905         length = len;
906 out:
907         kfree(newcon);
908         kfree(tcon);
909         kfree(scon);
910         return length;
911 }
912
913 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
914 {
915         char *con = NULL, *user = NULL, *ptr;
916         u32 sid, *sids = NULL;
917         ssize_t length;
918         char *newcon;
919         int i, rc;
920         u32 len, nsids;
921
922         length = task_has_security(current, SECURITY__COMPUTE_USER);
923         if (length)
924                 goto out;
925
926         length = -ENOMEM;
927         con = kzalloc(size + 1, GFP_KERNEL);
928         if (!con)
929                 goto out;
930
931         length = -ENOMEM;
932         user = kzalloc(size + 1, GFP_KERNEL);
933         if (!user)
934                 goto out;
935
936         length = -EINVAL;
937         if (sscanf(buf, "%s %s", con, user) != 2)
938                 goto out;
939
940         length = security_context_to_sid(con, strlen(con) + 1, &sid);
941         if (length)
942                 goto out;
943
944         length = security_get_user_sids(sid, user, &sids, &nsids);
945         if (length)
946                 goto out;
947
948         length = sprintf(buf, "%u", nsids) + 1;
949         ptr = buf + length;
950         for (i = 0; i < nsids; i++) {
951                 rc = security_sid_to_context(sids[i], &newcon, &len);
952                 if (rc) {
953                         length = rc;
954                         goto out;
955                 }
956                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
957                         kfree(newcon);
958                         length = -ERANGE;
959                         goto out;
960                 }
961                 memcpy(ptr, newcon, len);
962                 kfree(newcon);
963                 ptr += len;
964                 length += len;
965         }
966 out:
967         kfree(sids);
968         kfree(user);
969         kfree(con);
970         return length;
971 }
972
973 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
974 {
975         char *scon = NULL, *tcon = NULL;
976         u32 ssid, tsid, newsid;
977         u16 tclass;
978         ssize_t length;
979         char *newcon = NULL;
980         u32 len;
981
982         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
983         if (length)
984                 goto out;
985
986         length = -ENOMEM;
987         scon = kzalloc(size + 1, GFP_KERNEL);
988         if (!scon)
989                 goto out;
990
991         length = -ENOMEM;
992         tcon = kzalloc(size + 1, GFP_KERNEL);
993         if (!tcon)
994                 goto out;
995
996         length = -EINVAL;
997         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
998                 goto out;
999
1000         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
1001         if (length)
1002                 goto out;
1003
1004         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
1005         if (length)
1006                 goto out;
1007
1008         length = security_member_sid(ssid, tsid, tclass, &newsid);
1009         if (length)
1010                 goto out;
1011
1012         length = security_sid_to_context(newsid, &newcon, &len);
1013         if (length)
1014                 goto out;
1015
1016         length = -ERANGE;
1017         if (len > SIMPLE_TRANSACTION_LIMIT) {
1018                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
1019                         "payload max\n", __func__, len);
1020                 goto out;
1021         }
1022
1023         memcpy(buf, newcon, len);
1024         length = len;
1025 out:
1026         kfree(newcon);
1027         kfree(tcon);
1028         kfree(scon);
1029         return length;
1030 }
1031
1032 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1033 {
1034         struct inode *ret = new_inode(sb);
1035
1036         if (ret) {
1037                 ret->i_mode = mode;
1038                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
1039         }
1040         return ret;
1041 }
1042
1043 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1044                              size_t count, loff_t *ppos)
1045 {
1046         char *page = NULL;
1047         ssize_t length;
1048         ssize_t ret;
1049         int cur_enforcing;
1050         struct inode *inode = filep->f_path.dentry->d_inode;
1051         unsigned index = inode->i_ino & SEL_INO_MASK;
1052         const char *name = filep->f_path.dentry->d_name.name;
1053
1054         mutex_lock(&sel_mutex);
1055
1056         ret = -EINVAL;
1057         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1058                 goto out;
1059
1060         ret = -ENOMEM;
1061         page = (char *)get_zeroed_page(GFP_KERNEL);
1062         if (!page)
1063                 goto out;
1064
1065         cur_enforcing = security_get_bool_value(index);
1066         if (cur_enforcing < 0) {
1067                 ret = cur_enforcing;
1068                 goto out;
1069         }
1070         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1071                           bool_pending_values[index]);
1072         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1073 out:
1074         mutex_unlock(&sel_mutex);
1075         free_page((unsigned long)page);
1076         return ret;
1077 }
1078
1079 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1080                               size_t count, loff_t *ppos)
1081 {
1082         char *page = NULL;
1083         ssize_t length;
1084         int new_value;
1085         struct inode *inode = filep->f_path.dentry->d_inode;
1086         unsigned index = inode->i_ino & SEL_INO_MASK;
1087         const char *name = filep->f_path.dentry->d_name.name;
1088
1089         mutex_lock(&sel_mutex);
1090
1091         length = task_has_security(current, SECURITY__SETBOOL);
1092         if (length)
1093                 goto out;
1094
1095         length = -EINVAL;
1096         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1097                 goto out;
1098
1099         length = -ENOMEM;
1100         if (count >= PAGE_SIZE)
1101                 goto out;
1102
1103         /* No partial writes. */
1104         length = -EINVAL;
1105         if (*ppos != 0)
1106                 goto out;
1107
1108         length = -ENOMEM;
1109         page = (char *)get_zeroed_page(GFP_KERNEL);
1110         if (!page)
1111                 goto out;
1112
1113         length = -EFAULT;
1114         if (copy_from_user(page, buf, count))
1115                 goto out;
1116
1117         length = -EINVAL;
1118         if (sscanf(page, "%d", &new_value) != 1)
1119                 goto out;
1120
1121         if (new_value)
1122                 new_value = 1;
1123
1124         bool_pending_values[index] = new_value;
1125         length = count;
1126
1127 out:
1128         mutex_unlock(&sel_mutex);
1129         free_page((unsigned long) page);
1130         return length;
1131 }
1132
1133 static const struct file_operations sel_bool_ops = {
1134         .read           = sel_read_bool,
1135         .write          = sel_write_bool,
1136         .llseek         = generic_file_llseek,
1137 };
1138
1139 static ssize_t sel_commit_bools_write(struct file *filep,
1140                                       const char __user *buf,
1141                                       size_t count, loff_t *ppos)
1142 {
1143         char *page = NULL;
1144         ssize_t length;
1145         int new_value;
1146
1147         mutex_lock(&sel_mutex);
1148
1149         length = task_has_security(current, SECURITY__SETBOOL);
1150         if (length)
1151                 goto out;
1152
1153         length = -ENOMEM;
1154         if (count >= PAGE_SIZE)
1155                 goto out;
1156
1157         /* No partial writes. */
1158         length = -EINVAL;
1159         if (*ppos != 0)
1160                 goto out;
1161
1162         length = -ENOMEM;
1163         page = (char *)get_zeroed_page(GFP_KERNEL);
1164         if (!page)
1165                 goto out;
1166
1167         length = -EFAULT;
1168         if (copy_from_user(page, buf, count))
1169                 goto out;
1170
1171         length = -EINVAL;
1172         if (sscanf(page, "%d", &new_value) != 1)
1173                 goto out;
1174
1175         length = 0;
1176         if (new_value && bool_pending_values)
1177                 length = security_set_bools(bool_num, bool_pending_values);
1178
1179         if (!length)
1180                 length = count;
1181
1182 out:
1183         mutex_unlock(&sel_mutex);
1184         free_page((unsigned long) page);
1185         return length;
1186 }
1187
1188 static const struct file_operations sel_commit_bools_ops = {
1189         .write          = sel_commit_bools_write,
1190         .llseek         = generic_file_llseek,
1191 };
1192
1193 static void sel_remove_entries(struct dentry *de)
1194 {
1195         struct list_head *node;
1196
1197         spin_lock(&de->d_lock);
1198         node = de->d_subdirs.next;
1199         while (node != &de->d_subdirs) {
1200                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1201
1202                 spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
1203                 list_del_init(node);
1204
1205                 if (d->d_inode) {
1206                         dget_dlock(d);
1207                         spin_unlock(&de->d_lock);
1208                         spin_unlock(&d->d_lock);
1209                         d_delete(d);
1210                         simple_unlink(de->d_inode, d);
1211                         dput(d);
1212                         spin_lock(&de->d_lock);
1213                 } else
1214                         spin_unlock(&d->d_lock);
1215                 node = de->d_subdirs.next;
1216         }
1217
1218         spin_unlock(&de->d_lock);
1219 }
1220
1221 #define BOOL_DIR_NAME "booleans"
1222
1223 static int sel_make_bools(void)
1224 {
1225         int i, ret;
1226         ssize_t len;
1227         struct dentry *dentry = NULL;
1228         struct dentry *dir = bool_dir;
1229         struct inode *inode = NULL;
1230         struct inode_security_struct *isec;
1231         char **names = NULL, *page;
1232         int num;
1233         int *values = NULL;
1234         u32 sid;
1235
1236         /* remove any existing files */
1237         for (i = 0; i < bool_num; i++)
1238                 kfree(bool_pending_names[i]);
1239         kfree(bool_pending_names);
1240         kfree(bool_pending_values);
1241         bool_pending_names = NULL;
1242         bool_pending_values = NULL;
1243
1244         sel_remove_entries(dir);
1245
1246         ret = -ENOMEM;
1247         page = (char *)get_zeroed_page(GFP_KERNEL);
1248         if (!page)
1249                 goto out;
1250
1251         ret = security_get_bools(&num, &names, &values);
1252         if (ret)
1253                 goto out;
1254
1255         for (i = 0; i < num; i++) {
1256                 ret = -ENOMEM;
1257                 dentry = d_alloc_name(dir, names[i]);
1258                 if (!dentry)
1259                         goto out;
1260
1261                 ret = -ENOMEM;
1262                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1263                 if (!inode)
1264                         goto out;
1265
1266                 ret = -EINVAL;
1267                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1268                 if (len < 0)
1269                         goto out;
1270
1271                 ret = -ENAMETOOLONG;
1272                 if (len >= PAGE_SIZE)
1273                         goto out;
1274
1275                 isec = (struct inode_security_struct *)inode->i_security;
1276                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1277                 if (ret)
1278                         goto out;
1279
1280                 isec->sid = sid;
1281                 isec->initialized = 1;
1282                 inode->i_fop = &sel_bool_ops;
1283                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1284                 d_add(dentry, inode);
1285         }
1286         bool_num = num;
1287         bool_pending_names = names;
1288         bool_pending_values = values;
1289
1290         free_page((unsigned long)page);
1291         return 0;
1292 out:
1293         free_page((unsigned long)page);
1294
1295         if (names) {
1296                 for (i = 0; i < num; i++)
1297                         kfree(names[i]);
1298                 kfree(names);
1299         }
1300         kfree(values);
1301         sel_remove_entries(dir);
1302
1303         return ret;
1304 }
1305
1306 #define NULL_FILE_NAME "null"
1307
1308 struct dentry *selinux_null;
1309
1310 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1311                                             size_t count, loff_t *ppos)
1312 {
1313         char tmpbuf[TMPBUFLEN];
1314         ssize_t length;
1315
1316         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1317         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1318 }
1319
1320 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1321                                              const char __user *buf,
1322                                              size_t count, loff_t *ppos)
1323
1324 {
1325         char *page = NULL;
1326         ssize_t ret;
1327         int new_value;
1328
1329         ret = task_has_security(current, SECURITY__SETSECPARAM);
1330         if (ret)
1331                 goto out;
1332
1333         ret = -ENOMEM;
1334         if (count >= PAGE_SIZE)
1335                 goto out;
1336
1337         /* No partial writes. */
1338         ret = -EINVAL;
1339         if (*ppos != 0)
1340                 goto out;
1341
1342         ret = -ENOMEM;
1343         page = (char *)get_zeroed_page(GFP_KERNEL);
1344         if (!page)
1345                 goto out;
1346
1347         ret = -EFAULT;
1348         if (copy_from_user(page, buf, count))
1349                 goto out;
1350
1351         ret = -EINVAL;
1352         if (sscanf(page, "%u", &new_value) != 1)
1353                 goto out;
1354
1355         avc_cache_threshold = new_value;
1356
1357         ret = count;
1358 out:
1359         free_page((unsigned long)page);
1360         return ret;
1361 }
1362
1363 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1364                                        size_t count, loff_t *ppos)
1365 {
1366         char *page;
1367         ssize_t length;
1368
1369         page = (char *)__get_free_page(GFP_KERNEL);
1370         if (!page)
1371                 return -ENOMEM;
1372
1373         length = avc_get_hash_stats(page);
1374         if (length >= 0)
1375                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1376         free_page((unsigned long)page);
1377
1378         return length;
1379 }
1380
1381 static const struct file_operations sel_avc_cache_threshold_ops = {
1382         .read           = sel_read_avc_cache_threshold,
1383         .write          = sel_write_avc_cache_threshold,
1384         .llseek         = generic_file_llseek,
1385 };
1386
1387 static const struct file_operations sel_avc_hash_stats_ops = {
1388         .read           = sel_read_avc_hash_stats,
1389         .llseek         = generic_file_llseek,
1390 };
1391
1392 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1393 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1394 {
1395         int cpu;
1396
1397         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1398                 if (!cpu_possible(cpu))
1399                         continue;
1400                 *idx = cpu + 1;
1401                 return &per_cpu(avc_cache_stats, cpu);
1402         }
1403         return NULL;
1404 }
1405
1406 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1407 {
1408         loff_t n = *pos - 1;
1409
1410         if (*pos == 0)
1411                 return SEQ_START_TOKEN;
1412
1413         return sel_avc_get_stat_idx(&n);
1414 }
1415
1416 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1417 {
1418         return sel_avc_get_stat_idx(pos);
1419 }
1420
1421 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1422 {
1423         struct avc_cache_stats *st = v;
1424
1425         if (v == SEQ_START_TOKEN)
1426                 seq_printf(seq, "lookups hits misses allocations reclaims "
1427                            "frees\n");
1428         else {
1429                 unsigned int lookups = st->lookups;
1430                 unsigned int misses = st->misses;
1431                 unsigned int hits = lookups - misses;
1432                 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1433                            hits, misses, st->allocations,
1434                            st->reclaims, st->frees);
1435         }
1436         return 0;
1437 }
1438
1439 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1440 { }
1441
1442 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1443         .start          = sel_avc_stats_seq_start,
1444         .next           = sel_avc_stats_seq_next,
1445         .show           = sel_avc_stats_seq_show,
1446         .stop           = sel_avc_stats_seq_stop,
1447 };
1448
1449 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1450 {
1451         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1452 }
1453
1454 static const struct file_operations sel_avc_cache_stats_ops = {
1455         .open           = sel_open_avc_cache_stats,
1456         .read           = seq_read,
1457         .llseek         = seq_lseek,
1458         .release        = seq_release,
1459 };
1460 #endif
1461
1462 static int sel_make_avc_files(struct dentry *dir)
1463 {
1464         int i;
1465         static struct tree_descr files[] = {
1466                 { "cache_threshold",
1467                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1468                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1469 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1470                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1471 #endif
1472         };
1473
1474         for (i = 0; i < ARRAY_SIZE(files); i++) {
1475                 struct inode *inode;
1476                 struct dentry *dentry;
1477
1478                 dentry = d_alloc_name(dir, files[i].name);
1479                 if (!dentry)
1480                         return -ENOMEM;
1481
1482                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1483                 if (!inode)
1484                         return -ENOMEM;
1485
1486                 inode->i_fop = files[i].ops;
1487                 inode->i_ino = ++sel_last_ino;
1488                 d_add(dentry, inode);
1489         }
1490
1491         return 0;
1492 }
1493
1494 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1495                                 size_t count, loff_t *ppos)
1496 {
1497         struct inode *inode;
1498         char *con;
1499         u32 sid, len;
1500         ssize_t ret;
1501
1502         inode = file->f_path.dentry->d_inode;
1503         sid = inode->i_ino&SEL_INO_MASK;
1504         ret = security_sid_to_context(sid, &con, &len);
1505         if (ret)
1506                 return ret;
1507
1508         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1509         kfree(con);
1510         return ret;
1511 }
1512
1513 static const struct file_operations sel_initcon_ops = {
1514         .read           = sel_read_initcon,
1515         .llseek         = generic_file_llseek,
1516 };
1517
1518 static int sel_make_initcon_files(struct dentry *dir)
1519 {
1520         int i;
1521
1522         for (i = 1; i <= SECINITSID_NUM; i++) {
1523                 struct inode *inode;
1524                 struct dentry *dentry;
1525                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1526                 if (!dentry)
1527                         return -ENOMEM;
1528
1529                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1530                 if (!inode)
1531                         return -ENOMEM;
1532
1533                 inode->i_fop = &sel_initcon_ops;
1534                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1535                 d_add(dentry, inode);
1536         }
1537
1538         return 0;
1539 }
1540
1541 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1542 {
1543         return a / b - (a % b < 0);
1544 }
1545
1546 static inline unsigned long sel_class_to_ino(u16 class)
1547 {
1548         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1549 }
1550
1551 static inline u16 sel_ino_to_class(unsigned long ino)
1552 {
1553         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1554 }
1555
1556 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1557 {
1558         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1559 }
1560
1561 static inline u32 sel_ino_to_perm(unsigned long ino)
1562 {
1563         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1564 }
1565
1566 static ssize_t sel_read_class(struct file *file, char __user *buf,
1567                                 size_t count, loff_t *ppos)
1568 {
1569         ssize_t rc, len;
1570         char *page;
1571         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1572
1573         page = (char *)__get_free_page(GFP_KERNEL);
1574         if (!page)
1575                 return -ENOMEM;
1576
1577         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1578         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1579         free_page((unsigned long)page);
1580
1581         return rc;
1582 }
1583
1584 static const struct file_operations sel_class_ops = {
1585         .read           = sel_read_class,
1586         .llseek         = generic_file_llseek,
1587 };
1588
1589 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1590                                 size_t count, loff_t *ppos)
1591 {
1592         ssize_t rc, len;
1593         char *page;
1594         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1595
1596         page = (char *)__get_free_page(GFP_KERNEL);
1597         if (!page)
1598                 return -ENOMEM;
1599
1600         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1601         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1602         free_page((unsigned long)page);
1603
1604         return rc;
1605 }
1606
1607 static const struct file_operations sel_perm_ops = {
1608         .read           = sel_read_perm,
1609         .llseek         = generic_file_llseek,
1610 };
1611
1612 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1613                                   size_t count, loff_t *ppos)
1614 {
1615         int value;
1616         char tmpbuf[TMPBUFLEN];
1617         ssize_t length;
1618         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1619
1620         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1621         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1622
1623         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1624 }
1625
1626 static const struct file_operations sel_policycap_ops = {
1627         .read           = sel_read_policycap,
1628         .llseek         = generic_file_llseek,
1629 };
1630
1631 static int sel_make_perm_files(char *objclass, int classvalue,
1632                                 struct dentry *dir)
1633 {
1634         int i, rc, nperms;
1635         char **perms;
1636
1637         rc = security_get_permissions(objclass, &perms, &nperms);
1638         if (rc)
1639                 return rc;
1640
1641         for (i = 0; i < nperms; i++) {
1642                 struct inode *inode;
1643                 struct dentry *dentry;
1644
1645                 rc = -ENOMEM;
1646                 dentry = d_alloc_name(dir, perms[i]);
1647                 if (!dentry)
1648                         goto out;
1649
1650                 rc = -ENOMEM;
1651                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1652                 if (!inode)
1653                         goto out;
1654
1655                 inode->i_fop = &sel_perm_ops;
1656                 /* i+1 since perm values are 1-indexed */
1657                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1658                 d_add(dentry, inode);
1659         }
1660         rc = 0;
1661 out:
1662         for (i = 0; i < nperms; i++)
1663                 kfree(perms[i]);
1664         kfree(perms);
1665         return rc;
1666 }
1667
1668 static int sel_make_class_dir_entries(char *classname, int index,
1669                                         struct dentry *dir)
1670 {
1671         struct dentry *dentry = NULL;
1672         struct inode *inode = NULL;
1673         int rc;
1674
1675         dentry = d_alloc_name(dir, "index");
1676         if (!dentry)
1677                 return -ENOMEM;
1678
1679         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1680         if (!inode)
1681                 return -ENOMEM;
1682
1683         inode->i_fop = &sel_class_ops;
1684         inode->i_ino = sel_class_to_ino(index);
1685         d_add(dentry, inode);
1686
1687         dentry = d_alloc_name(dir, "perms");
1688         if (!dentry)
1689                 return -ENOMEM;
1690
1691         rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1692         if (rc)
1693                 return rc;
1694
1695         rc = sel_make_perm_files(classname, index, dentry);
1696
1697         return rc;
1698 }
1699
1700 static void sel_remove_classes(void)
1701 {
1702         struct list_head *class_node;
1703
1704         list_for_each(class_node, &class_dir->d_subdirs) {
1705                 struct dentry *class_subdir = list_entry(class_node,
1706                                         struct dentry, d_u.d_child);
1707                 struct list_head *class_subdir_node;
1708
1709                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1710                         struct dentry *d = list_entry(class_subdir_node,
1711                                                 struct dentry, d_u.d_child);
1712
1713                         if (d->d_inode)
1714                                 if (d->d_inode->i_mode & S_IFDIR)
1715                                         sel_remove_entries(d);
1716                 }
1717
1718                 sel_remove_entries(class_subdir);
1719         }
1720
1721         sel_remove_entries(class_dir);
1722 }
1723
1724 static int sel_make_classes(void)
1725 {
1726         int rc, nclasses, i;
1727         char **classes;
1728
1729         /* delete any existing entries */
1730         sel_remove_classes();
1731
1732         rc = security_get_classes(&classes, &nclasses);
1733         if (rc)
1734                 return rc;
1735
1736         /* +2 since classes are 1-indexed */
1737         last_class_ino = sel_class_to_ino(nclasses + 2);
1738
1739         for (i = 0; i < nclasses; i++) {
1740                 struct dentry *class_name_dir;
1741
1742                 rc = -ENOMEM;
1743                 class_name_dir = d_alloc_name(class_dir, classes[i]);
1744                 if (!class_name_dir)
1745                         goto out;
1746
1747                 rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1748                                 &last_class_ino);
1749                 if (rc)
1750                         goto out;
1751
1752                 /* i+1 since class values are 1-indexed */
1753                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1754                                 class_name_dir);
1755                 if (rc)
1756                         goto out;
1757         }
1758         rc = 0;
1759 out:
1760         for (i = 0; i < nclasses; i++)
1761                 kfree(classes[i]);
1762         kfree(classes);
1763         return rc;
1764 }
1765
1766 static int sel_make_policycap(void)
1767 {
1768         unsigned int iter;
1769         struct dentry *dentry = NULL;
1770         struct inode *inode = NULL;
1771
1772         sel_remove_entries(policycap_dir);
1773
1774         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1775                 if (iter < ARRAY_SIZE(policycap_names))
1776                         dentry = d_alloc_name(policycap_dir,
1777                                               policycap_names[iter]);
1778                 else
1779                         dentry = d_alloc_name(policycap_dir, "unknown");
1780
1781                 if (dentry == NULL)
1782                         return -ENOMEM;
1783
1784                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1785                 if (inode == NULL)
1786                         return -ENOMEM;
1787
1788                 inode->i_fop = &sel_policycap_ops;
1789                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1790                 d_add(dentry, inode);
1791         }
1792
1793         return 0;
1794 }
1795
1796 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1797                         unsigned long *ino)
1798 {
1799         struct inode *inode;
1800
1801         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1802         if (!inode)
1803                 return -ENOMEM;
1804
1805         inode->i_op = &simple_dir_inode_operations;
1806         inode->i_fop = &simple_dir_operations;
1807         inode->i_ino = ++(*ino);
1808         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1809         inc_nlink(inode);
1810         d_add(dentry, inode);
1811         /* bump link count on parent directory, too */
1812         inc_nlink(dir);
1813
1814         return 0;
1815 }
1816
1817 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1818 {
1819         int ret;
1820         struct dentry *dentry;
1821         struct inode *inode, *root_inode;
1822         struct inode_security_struct *isec;
1823
1824         static struct tree_descr selinux_files[] = {
1825                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1826                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1827                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1828                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1829                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1830                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1831                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1832                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1833                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1834                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1835                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1836                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1837                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1838                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1839                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1840                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1841                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUSR},
1842                 /* last one */ {""}
1843         };
1844         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1845         if (ret)
1846                 goto err;
1847
1848         root_inode = sb->s_root->d_inode;
1849
1850         ret = -ENOMEM;
1851         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1852         if (!dentry)
1853                 goto err;
1854
1855         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1856         if (ret)
1857                 goto err;
1858
1859         bool_dir = dentry;
1860
1861         ret = -ENOMEM;
1862         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1863         if (!dentry)
1864                 goto err;
1865
1866         ret = -ENOMEM;
1867         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1868         if (!inode)
1869                 goto err;
1870
1871         inode->i_ino = ++sel_last_ino;
1872         isec = (struct inode_security_struct *)inode->i_security;
1873         isec->sid = SECINITSID_DEVNULL;
1874         isec->sclass = SECCLASS_CHR_FILE;
1875         isec->initialized = 1;
1876
1877         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1878         d_add(dentry, inode);
1879         selinux_null = dentry;
1880
1881         ret = -ENOMEM;
1882         dentry = d_alloc_name(sb->s_root, "avc");
1883         if (!dentry)
1884                 goto err;
1885
1886         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1887         if (ret)
1888                 goto err;
1889
1890         ret = sel_make_avc_files(dentry);
1891         if (ret)
1892                 goto err;
1893
1894         ret = -ENOMEM;
1895         dentry = d_alloc_name(sb->s_root, "initial_contexts");
1896         if (!dentry)
1897                 goto err;
1898
1899         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1900         if (ret)
1901                 goto err;
1902
1903         ret = sel_make_initcon_files(dentry);
1904         if (ret)
1905                 goto err;
1906
1907         ret = -ENOMEM;
1908         dentry = d_alloc_name(sb->s_root, "class");
1909         if (!dentry)
1910                 goto err;
1911
1912         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1913         if (ret)
1914                 goto err;
1915
1916         class_dir = dentry;
1917
1918         ret = -ENOMEM;
1919         dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1920         if (!dentry)
1921                 goto err;
1922
1923         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1924         if (ret)
1925                 goto err;
1926
1927         policycap_dir = dentry;
1928
1929         return 0;
1930 err:
1931         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1932                 __func__);
1933         return ret;
1934 }
1935
1936 static struct dentry *sel_mount(struct file_system_type *fs_type,
1937                       int flags, const char *dev_name, void *data)
1938 {
1939         return mount_single(fs_type, flags, data, sel_fill_super);
1940 }
1941
1942 static struct file_system_type sel_fs_type = {
1943         .name           = "selinuxfs",
1944         .mount          = sel_mount,
1945         .kill_sb        = kill_litter_super,
1946 };
1947
1948 struct vfsmount *selinuxfs_mount;
1949 static struct kobject *selinuxfs_kobj;
1950
1951 static int __init init_sel_fs(void)
1952 {
1953         int err;
1954
1955         if (!selinux_enabled)
1956                 return 0;
1957
1958         selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj);
1959         if (!selinuxfs_kobj)
1960                 return -ENOMEM;
1961
1962         err = register_filesystem(&sel_fs_type);
1963         if (err) {
1964                 kobject_put(selinuxfs_kobj);
1965                 return err;
1966         }
1967
1968         selinuxfs_mount = kern_mount(&sel_fs_type);
1969         if (IS_ERR(selinuxfs_mount)) {
1970                 printk(KERN_ERR "selinuxfs:  could not mount!\n");
1971                 err = PTR_ERR(selinuxfs_mount);
1972                 selinuxfs_mount = NULL;
1973         }
1974
1975         return err;
1976 }
1977
1978 __initcall(init_sel_fs);
1979
1980 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1981 void exit_sel_fs(void)
1982 {
1983         kobject_put(selinuxfs_kobj);
1984         kern_unmount(selinuxfs_mount);
1985         unregister_filesystem(&sel_fs_type);
1986 }
1987 #endif