proc: stats: Use arch_idle_time for idle and iowait times if available
[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 struct dentry *sel_make_dir(struct dentry *dir, const char *name,
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 ssize_t sel_write_create(struct file *file, char *buf, size_t size)
753 {
754         char *scon = NULL, *tcon = NULL;
755         char *namebuf = NULL, *objname = NULL;
756         u32 ssid, tsid, newsid;
757         u16 tclass;
758         ssize_t length;
759         char *newcon = NULL;
760         u32 len;
761         int nargs;
762
763         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
764         if (length)
765                 goto out;
766
767         length = -ENOMEM;
768         scon = kzalloc(size + 1, GFP_KERNEL);
769         if (!scon)
770                 goto out;
771
772         length = -ENOMEM;
773         tcon = kzalloc(size + 1, GFP_KERNEL);
774         if (!tcon)
775                 goto out;
776
777         length = -ENOMEM;
778         namebuf = kzalloc(size + 1, GFP_KERNEL);
779         if (!namebuf)
780                 goto out;
781
782         length = -EINVAL;
783         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
784         if (nargs < 3 || nargs > 4)
785                 goto out;
786         if (nargs == 4) {
787                 /*
788                  * If and when the name of new object to be queried contains
789                  * either whitespace or multibyte characters, they shall be
790                  * encoded based on the percentage-encoding rule.
791                  * If not encoded, the sscanf logic picks up only left-half
792                  * of the supplied name; splitted by a whitespace unexpectedly.
793                  */
794                 char   *r, *w;
795                 int     c1, c2;
796
797                 r = w = namebuf;
798                 do {
799                         c1 = *r++;
800                         if (c1 == '+')
801                                 c1 = ' ';
802                         else if (c1 == '%') {
803                                 c1 = hex_to_bin(*r++);
804                                 if (c1 < 0)
805                                         goto out;
806                                 c2 = hex_to_bin(*r++);
807                                 if (c2 < 0)
808                                         goto out;
809                                 c1 = (c1 << 4) | c2;
810                         }
811                         *w++ = c1;
812                 } while (c1 != '\0');
813
814                 objname = namebuf;
815         }
816
817         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
818         if (length)
819                 goto out;
820
821         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
822         if (length)
823                 goto out;
824
825         length = security_transition_sid_user(ssid, tsid, tclass,
826                                               objname, &newsid);
827         if (length)
828                 goto out;
829
830         length = security_sid_to_context(newsid, &newcon, &len);
831         if (length)
832                 goto out;
833
834         length = -ERANGE;
835         if (len > SIMPLE_TRANSACTION_LIMIT) {
836                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
837                         "payload max\n", __func__, len);
838                 goto out;
839         }
840
841         memcpy(buf, newcon, len);
842         length = len;
843 out:
844         kfree(newcon);
845         kfree(namebuf);
846         kfree(tcon);
847         kfree(scon);
848         return length;
849 }
850
851 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
852 {
853         char *scon = NULL, *tcon = NULL;
854         u32 ssid, tsid, newsid;
855         u16 tclass;
856         ssize_t length;
857         char *newcon = NULL;
858         u32 len;
859
860         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
861         if (length)
862                 goto out;
863
864         length = -ENOMEM;
865         scon = kzalloc(size + 1, GFP_KERNEL);
866         if (!scon)
867                 goto out;
868
869         length = -ENOMEM;
870         tcon = kzalloc(size + 1, GFP_KERNEL);
871         if (!tcon)
872                 goto out;
873
874         length = -EINVAL;
875         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
876                 goto out;
877
878         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
879         if (length)
880                 goto out;
881
882         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
883         if (length)
884                 goto out;
885
886         length = security_change_sid(ssid, tsid, tclass, &newsid);
887         if (length)
888                 goto out;
889
890         length = security_sid_to_context(newsid, &newcon, &len);
891         if (length)
892                 goto out;
893
894         length = -ERANGE;
895         if (len > SIMPLE_TRANSACTION_LIMIT)
896                 goto out;
897
898         memcpy(buf, newcon, len);
899         length = len;
900 out:
901         kfree(newcon);
902         kfree(tcon);
903         kfree(scon);
904         return length;
905 }
906
907 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
908 {
909         char *con = NULL, *user = NULL, *ptr;
910         u32 sid, *sids = NULL;
911         ssize_t length;
912         char *newcon;
913         int i, rc;
914         u32 len, nsids;
915
916         length = task_has_security(current, SECURITY__COMPUTE_USER);
917         if (length)
918                 goto out;
919
920         length = -ENOMEM;
921         con = kzalloc(size + 1, GFP_KERNEL);
922         if (!con)
923                 goto out;
924
925         length = -ENOMEM;
926         user = kzalloc(size + 1, GFP_KERNEL);
927         if (!user)
928                 goto out;
929
930         length = -EINVAL;
931         if (sscanf(buf, "%s %s", con, user) != 2)
932                 goto out;
933
934         length = security_context_to_sid(con, strlen(con) + 1, &sid);
935         if (length)
936                 goto out;
937
938         length = security_get_user_sids(sid, user, &sids, &nsids);
939         if (length)
940                 goto out;
941
942         length = sprintf(buf, "%u", nsids) + 1;
943         ptr = buf + length;
944         for (i = 0; i < nsids; i++) {
945                 rc = security_sid_to_context(sids[i], &newcon, &len);
946                 if (rc) {
947                         length = rc;
948                         goto out;
949                 }
950                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
951                         kfree(newcon);
952                         length = -ERANGE;
953                         goto out;
954                 }
955                 memcpy(ptr, newcon, len);
956                 kfree(newcon);
957                 ptr += len;
958                 length += len;
959         }
960 out:
961         kfree(sids);
962         kfree(user);
963         kfree(con);
964         return length;
965 }
966
967 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
968 {
969         char *scon = NULL, *tcon = NULL;
970         u32 ssid, tsid, newsid;
971         u16 tclass;
972         ssize_t length;
973         char *newcon = NULL;
974         u32 len;
975
976         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
977         if (length)
978                 goto out;
979
980         length = -ENOMEM;
981         scon = kzalloc(size + 1, GFP_KERNEL);
982         if (!scon)
983                 goto out;
984
985         length = -ENOMEM;
986         tcon = kzalloc(size + 1, GFP_KERNEL);
987         if (!tcon)
988                 goto out;
989
990         length = -EINVAL;
991         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
992                 goto out;
993
994         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
995         if (length)
996                 goto out;
997
998         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
999         if (length)
1000                 goto out;
1001
1002         length = security_member_sid(ssid, tsid, tclass, &newsid);
1003         if (length)
1004                 goto out;
1005
1006         length = security_sid_to_context(newsid, &newcon, &len);
1007         if (length)
1008                 goto out;
1009
1010         length = -ERANGE;
1011         if (len > SIMPLE_TRANSACTION_LIMIT) {
1012                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
1013                         "payload max\n", __func__, len);
1014                 goto out;
1015         }
1016
1017         memcpy(buf, newcon, len);
1018         length = len;
1019 out:
1020         kfree(newcon);
1021         kfree(tcon);
1022         kfree(scon);
1023         return length;
1024 }
1025
1026 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1027 {
1028         struct inode *ret = new_inode(sb);
1029
1030         if (ret) {
1031                 ret->i_mode = mode;
1032                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
1033         }
1034         return ret;
1035 }
1036
1037 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1038                              size_t count, loff_t *ppos)
1039 {
1040         char *page = NULL;
1041         ssize_t length;
1042         ssize_t ret;
1043         int cur_enforcing;
1044         struct inode *inode = filep->f_path.dentry->d_inode;
1045         unsigned index = inode->i_ino & SEL_INO_MASK;
1046         const char *name = filep->f_path.dentry->d_name.name;
1047
1048         mutex_lock(&sel_mutex);
1049
1050         ret = -EINVAL;
1051         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1052                 goto out;
1053
1054         ret = -ENOMEM;
1055         page = (char *)get_zeroed_page(GFP_KERNEL);
1056         if (!page)
1057                 goto out;
1058
1059         cur_enforcing = security_get_bool_value(index);
1060         if (cur_enforcing < 0) {
1061                 ret = cur_enforcing;
1062                 goto out;
1063         }
1064         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1065                           bool_pending_values[index]);
1066         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1067 out:
1068         mutex_unlock(&sel_mutex);
1069         free_page((unsigned long)page);
1070         return ret;
1071 }
1072
1073 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1074                               size_t count, loff_t *ppos)
1075 {
1076         char *page = NULL;
1077         ssize_t length;
1078         int new_value;
1079         struct inode *inode = filep->f_path.dentry->d_inode;
1080         unsigned index = inode->i_ino & SEL_INO_MASK;
1081         const char *name = filep->f_path.dentry->d_name.name;
1082
1083         mutex_lock(&sel_mutex);
1084
1085         length = task_has_security(current, SECURITY__SETBOOL);
1086         if (length)
1087                 goto out;
1088
1089         length = -EINVAL;
1090         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1091                 goto out;
1092
1093         length = -ENOMEM;
1094         if (count >= PAGE_SIZE)
1095                 goto out;
1096
1097         /* No partial writes. */
1098         length = -EINVAL;
1099         if (*ppos != 0)
1100                 goto out;
1101
1102         length = -ENOMEM;
1103         page = (char *)get_zeroed_page(GFP_KERNEL);
1104         if (!page)
1105                 goto out;
1106
1107         length = -EFAULT;
1108         if (copy_from_user(page, buf, count))
1109                 goto out;
1110
1111         length = -EINVAL;
1112         if (sscanf(page, "%d", &new_value) != 1)
1113                 goto out;
1114
1115         if (new_value)
1116                 new_value = 1;
1117
1118         bool_pending_values[index] = new_value;
1119         length = count;
1120
1121 out:
1122         mutex_unlock(&sel_mutex);
1123         free_page((unsigned long) page);
1124         return length;
1125 }
1126
1127 static const struct file_operations sel_bool_ops = {
1128         .read           = sel_read_bool,
1129         .write          = sel_write_bool,
1130         .llseek         = generic_file_llseek,
1131 };
1132
1133 static ssize_t sel_commit_bools_write(struct file *filep,
1134                                       const char __user *buf,
1135                                       size_t count, loff_t *ppos)
1136 {
1137         char *page = NULL;
1138         ssize_t length;
1139         int new_value;
1140
1141         mutex_lock(&sel_mutex);
1142
1143         length = task_has_security(current, SECURITY__SETBOOL);
1144         if (length)
1145                 goto out;
1146
1147         length = -ENOMEM;
1148         if (count >= PAGE_SIZE)
1149                 goto out;
1150
1151         /* No partial writes. */
1152         length = -EINVAL;
1153         if (*ppos != 0)
1154                 goto out;
1155
1156         length = -ENOMEM;
1157         page = (char *)get_zeroed_page(GFP_KERNEL);
1158         if (!page)
1159                 goto out;
1160
1161         length = -EFAULT;
1162         if (copy_from_user(page, buf, count))
1163                 goto out;
1164
1165         length = -EINVAL;
1166         if (sscanf(page, "%d", &new_value) != 1)
1167                 goto out;
1168
1169         length = 0;
1170         if (new_value && bool_pending_values)
1171                 length = security_set_bools(bool_num, bool_pending_values);
1172
1173         if (!length)
1174                 length = count;
1175
1176 out:
1177         mutex_unlock(&sel_mutex);
1178         free_page((unsigned long) page);
1179         return length;
1180 }
1181
1182 static const struct file_operations sel_commit_bools_ops = {
1183         .write          = sel_commit_bools_write,
1184         .llseek         = generic_file_llseek,
1185 };
1186
1187 static void sel_remove_entries(struct dentry *de)
1188 {
1189         struct list_head *node;
1190
1191         spin_lock(&de->d_lock);
1192         node = de->d_subdirs.next;
1193         while (node != &de->d_subdirs) {
1194                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1195
1196                 spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
1197                 list_del_init(node);
1198
1199                 if (d->d_inode) {
1200                         dget_dlock(d);
1201                         spin_unlock(&de->d_lock);
1202                         spin_unlock(&d->d_lock);
1203                         d_delete(d);
1204                         simple_unlink(de->d_inode, d);
1205                         dput(d);
1206                         spin_lock(&de->d_lock);
1207                 } else
1208                         spin_unlock(&d->d_lock);
1209                 node = de->d_subdirs.next;
1210         }
1211
1212         spin_unlock(&de->d_lock);
1213 }
1214
1215 #define BOOL_DIR_NAME "booleans"
1216
1217 static int sel_make_bools(void)
1218 {
1219         int i, ret;
1220         ssize_t len;
1221         struct dentry *dentry = NULL;
1222         struct dentry *dir = bool_dir;
1223         struct inode *inode = NULL;
1224         struct inode_security_struct *isec;
1225         char **names = NULL, *page;
1226         int num;
1227         int *values = NULL;
1228         u32 sid;
1229
1230         /* remove any existing files */
1231         for (i = 0; i < bool_num; i++)
1232                 kfree(bool_pending_names[i]);
1233         kfree(bool_pending_names);
1234         kfree(bool_pending_values);
1235         bool_pending_names = NULL;
1236         bool_pending_values = NULL;
1237
1238         sel_remove_entries(dir);
1239
1240         ret = -ENOMEM;
1241         page = (char *)get_zeroed_page(GFP_KERNEL);
1242         if (!page)
1243                 goto out;
1244
1245         ret = security_get_bools(&num, &names, &values);
1246         if (ret)
1247                 goto out;
1248
1249         for (i = 0; i < num; i++) {
1250                 ret = -ENOMEM;
1251                 dentry = d_alloc_name(dir, names[i]);
1252                 if (!dentry)
1253                         goto out;
1254
1255                 ret = -ENOMEM;
1256                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1257                 if (!inode)
1258                         goto out;
1259
1260                 ret = -EINVAL;
1261                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1262                 if (len < 0)
1263                         goto out;
1264
1265                 ret = -ENAMETOOLONG;
1266                 if (len >= PAGE_SIZE)
1267                         goto out;
1268
1269                 isec = (struct inode_security_struct *)inode->i_security;
1270                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1271                 if (ret)
1272                         goto out;
1273
1274                 isec->sid = sid;
1275                 isec->initialized = 1;
1276                 inode->i_fop = &sel_bool_ops;
1277                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1278                 d_add(dentry, inode);
1279         }
1280         bool_num = num;
1281         bool_pending_names = names;
1282         bool_pending_values = values;
1283
1284         free_page((unsigned long)page);
1285         return 0;
1286 out:
1287         free_page((unsigned long)page);
1288
1289         if (names) {
1290                 for (i = 0; i < num; i++)
1291                         kfree(names[i]);
1292                 kfree(names);
1293         }
1294         kfree(values);
1295         sel_remove_entries(dir);
1296
1297         return ret;
1298 }
1299
1300 #define NULL_FILE_NAME "null"
1301
1302 struct dentry *selinux_null;
1303
1304 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1305                                             size_t count, loff_t *ppos)
1306 {
1307         char tmpbuf[TMPBUFLEN];
1308         ssize_t length;
1309
1310         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1311         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1312 }
1313
1314 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1315                                              const char __user *buf,
1316                                              size_t count, loff_t *ppos)
1317
1318 {
1319         char *page = NULL;
1320         ssize_t ret;
1321         int new_value;
1322
1323         ret = task_has_security(current, SECURITY__SETSECPARAM);
1324         if (ret)
1325                 goto out;
1326
1327         ret = -ENOMEM;
1328         if (count >= PAGE_SIZE)
1329                 goto out;
1330
1331         /* No partial writes. */
1332         ret = -EINVAL;
1333         if (*ppos != 0)
1334                 goto out;
1335
1336         ret = -ENOMEM;
1337         page = (char *)get_zeroed_page(GFP_KERNEL);
1338         if (!page)
1339                 goto out;
1340
1341         ret = -EFAULT;
1342         if (copy_from_user(page, buf, count))
1343                 goto out;
1344
1345         ret = -EINVAL;
1346         if (sscanf(page, "%u", &new_value) != 1)
1347                 goto out;
1348
1349         avc_cache_threshold = new_value;
1350
1351         ret = count;
1352 out:
1353         free_page((unsigned long)page);
1354         return ret;
1355 }
1356
1357 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1358                                        size_t count, loff_t *ppos)
1359 {
1360         char *page;
1361         ssize_t length;
1362
1363         page = (char *)__get_free_page(GFP_KERNEL);
1364         if (!page)
1365                 return -ENOMEM;
1366
1367         length = avc_get_hash_stats(page);
1368         if (length >= 0)
1369                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1370         free_page((unsigned long)page);
1371
1372         return length;
1373 }
1374
1375 static const struct file_operations sel_avc_cache_threshold_ops = {
1376         .read           = sel_read_avc_cache_threshold,
1377         .write          = sel_write_avc_cache_threshold,
1378         .llseek         = generic_file_llseek,
1379 };
1380
1381 static const struct file_operations sel_avc_hash_stats_ops = {
1382         .read           = sel_read_avc_hash_stats,
1383         .llseek         = generic_file_llseek,
1384 };
1385
1386 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1387 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1388 {
1389         int cpu;
1390
1391         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1392                 if (!cpu_possible(cpu))
1393                         continue;
1394                 *idx = cpu + 1;
1395                 return &per_cpu(avc_cache_stats, cpu);
1396         }
1397         return NULL;
1398 }
1399
1400 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1401 {
1402         loff_t n = *pos - 1;
1403
1404         if (*pos == 0)
1405                 return SEQ_START_TOKEN;
1406
1407         return sel_avc_get_stat_idx(&n);
1408 }
1409
1410 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1411 {
1412         return sel_avc_get_stat_idx(pos);
1413 }
1414
1415 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1416 {
1417         struct avc_cache_stats *st = v;
1418
1419         if (v == SEQ_START_TOKEN)
1420                 seq_printf(seq, "lookups hits misses allocations reclaims "
1421                            "frees\n");
1422         else {
1423                 unsigned int lookups = st->lookups;
1424                 unsigned int misses = st->misses;
1425                 unsigned int hits = lookups - misses;
1426                 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1427                            hits, misses, st->allocations,
1428                            st->reclaims, st->frees);
1429         }
1430         return 0;
1431 }
1432
1433 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1434 { }
1435
1436 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1437         .start          = sel_avc_stats_seq_start,
1438         .next           = sel_avc_stats_seq_next,
1439         .show           = sel_avc_stats_seq_show,
1440         .stop           = sel_avc_stats_seq_stop,
1441 };
1442
1443 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1444 {
1445         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1446 }
1447
1448 static const struct file_operations sel_avc_cache_stats_ops = {
1449         .open           = sel_open_avc_cache_stats,
1450         .read           = seq_read,
1451         .llseek         = seq_lseek,
1452         .release        = seq_release,
1453 };
1454 #endif
1455
1456 static int sel_make_avc_files(struct dentry *dir)
1457 {
1458         int i;
1459         static struct tree_descr files[] = {
1460                 { "cache_threshold",
1461                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1462                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1463 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1464                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1465 #endif
1466         };
1467
1468         for (i = 0; i < ARRAY_SIZE(files); i++) {
1469                 struct inode *inode;
1470                 struct dentry *dentry;
1471
1472                 dentry = d_alloc_name(dir, files[i].name);
1473                 if (!dentry)
1474                         return -ENOMEM;
1475
1476                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1477                 if (!inode)
1478                         return -ENOMEM;
1479
1480                 inode->i_fop = files[i].ops;
1481                 inode->i_ino = ++sel_last_ino;
1482                 d_add(dentry, inode);
1483         }
1484
1485         return 0;
1486 }
1487
1488 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1489                                 size_t count, loff_t *ppos)
1490 {
1491         struct inode *inode;
1492         char *con;
1493         u32 sid, len;
1494         ssize_t ret;
1495
1496         inode = file->f_path.dentry->d_inode;
1497         sid = inode->i_ino&SEL_INO_MASK;
1498         ret = security_sid_to_context(sid, &con, &len);
1499         if (ret)
1500                 return ret;
1501
1502         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1503         kfree(con);
1504         return ret;
1505 }
1506
1507 static const struct file_operations sel_initcon_ops = {
1508         .read           = sel_read_initcon,
1509         .llseek         = generic_file_llseek,
1510 };
1511
1512 static int sel_make_initcon_files(struct dentry *dir)
1513 {
1514         int i;
1515
1516         for (i = 1; i <= SECINITSID_NUM; i++) {
1517                 struct inode *inode;
1518                 struct dentry *dentry;
1519                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1520                 if (!dentry)
1521                         return -ENOMEM;
1522
1523                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1524                 if (!inode)
1525                         return -ENOMEM;
1526
1527                 inode->i_fop = &sel_initcon_ops;
1528                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1529                 d_add(dentry, inode);
1530         }
1531
1532         return 0;
1533 }
1534
1535 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1536 {
1537         return a / b - (a % b < 0);
1538 }
1539
1540 static inline unsigned long sel_class_to_ino(u16 class)
1541 {
1542         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1543 }
1544
1545 static inline u16 sel_ino_to_class(unsigned long ino)
1546 {
1547         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1548 }
1549
1550 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1551 {
1552         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1553 }
1554
1555 static inline u32 sel_ino_to_perm(unsigned long ino)
1556 {
1557         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1558 }
1559
1560 static ssize_t sel_read_class(struct file *file, char __user *buf,
1561                                 size_t count, loff_t *ppos)
1562 {
1563         ssize_t rc, len;
1564         char *page;
1565         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1566
1567         page = (char *)__get_free_page(GFP_KERNEL);
1568         if (!page)
1569                 return -ENOMEM;
1570
1571         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1572         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1573         free_page((unsigned long)page);
1574
1575         return rc;
1576 }
1577
1578 static const struct file_operations sel_class_ops = {
1579         .read           = sel_read_class,
1580         .llseek         = generic_file_llseek,
1581 };
1582
1583 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1584                                 size_t count, loff_t *ppos)
1585 {
1586         ssize_t rc, len;
1587         char *page;
1588         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1589
1590         page = (char *)__get_free_page(GFP_KERNEL);
1591         if (!page)
1592                 return -ENOMEM;
1593
1594         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1595         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1596         free_page((unsigned long)page);
1597
1598         return rc;
1599 }
1600
1601 static const struct file_operations sel_perm_ops = {
1602         .read           = sel_read_perm,
1603         .llseek         = generic_file_llseek,
1604 };
1605
1606 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1607                                   size_t count, loff_t *ppos)
1608 {
1609         int value;
1610         char tmpbuf[TMPBUFLEN];
1611         ssize_t length;
1612         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1613
1614         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1615         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1616
1617         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1618 }
1619
1620 static const struct file_operations sel_policycap_ops = {
1621         .read           = sel_read_policycap,
1622         .llseek         = generic_file_llseek,
1623 };
1624
1625 static int sel_make_perm_files(char *objclass, int classvalue,
1626                                 struct dentry *dir)
1627 {
1628         int i, rc, nperms;
1629         char **perms;
1630
1631         rc = security_get_permissions(objclass, &perms, &nperms);
1632         if (rc)
1633                 return rc;
1634
1635         for (i = 0; i < nperms; i++) {
1636                 struct inode *inode;
1637                 struct dentry *dentry;
1638
1639                 rc = -ENOMEM;
1640                 dentry = d_alloc_name(dir, perms[i]);
1641                 if (!dentry)
1642                         goto out;
1643
1644                 rc = -ENOMEM;
1645                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1646                 if (!inode)
1647                         goto out;
1648
1649                 inode->i_fop = &sel_perm_ops;
1650                 /* i+1 since perm values are 1-indexed */
1651                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1652                 d_add(dentry, inode);
1653         }
1654         rc = 0;
1655 out:
1656         for (i = 0; i < nperms; i++)
1657                 kfree(perms[i]);
1658         kfree(perms);
1659         return rc;
1660 }
1661
1662 static int sel_make_class_dir_entries(char *classname, int index,
1663                                         struct dentry *dir)
1664 {
1665         struct dentry *dentry = NULL;
1666         struct inode *inode = NULL;
1667         int rc;
1668
1669         dentry = d_alloc_name(dir, "index");
1670         if (!dentry)
1671                 return -ENOMEM;
1672
1673         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1674         if (!inode)
1675                 return -ENOMEM;
1676
1677         inode->i_fop = &sel_class_ops;
1678         inode->i_ino = sel_class_to_ino(index);
1679         d_add(dentry, inode);
1680
1681         dentry = sel_make_dir(dir, "perms", &last_class_ino);
1682         if (IS_ERR(dentry))
1683                 return PTR_ERR(dentry);
1684
1685         rc = sel_make_perm_files(classname, index, dentry);
1686
1687         return rc;
1688 }
1689
1690 static void sel_remove_classes(void)
1691 {
1692         struct list_head *class_node;
1693
1694         list_for_each(class_node, &class_dir->d_subdirs) {
1695                 struct dentry *class_subdir = list_entry(class_node,
1696                                         struct dentry, d_u.d_child);
1697                 struct list_head *class_subdir_node;
1698
1699                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1700                         struct dentry *d = list_entry(class_subdir_node,
1701                                                 struct dentry, d_u.d_child);
1702
1703                         if (d->d_inode)
1704                                 if (d->d_inode->i_mode & S_IFDIR)
1705                                         sel_remove_entries(d);
1706                 }
1707
1708                 sel_remove_entries(class_subdir);
1709         }
1710
1711         sel_remove_entries(class_dir);
1712 }
1713
1714 static int sel_make_classes(void)
1715 {
1716         int rc, nclasses, i;
1717         char **classes;
1718
1719         /* delete any existing entries */
1720         sel_remove_classes();
1721
1722         rc = security_get_classes(&classes, &nclasses);
1723         if (rc)
1724                 return rc;
1725
1726         /* +2 since classes are 1-indexed */
1727         last_class_ino = sel_class_to_ino(nclasses + 2);
1728
1729         for (i = 0; i < nclasses; i++) {
1730                 struct dentry *class_name_dir;
1731
1732                 class_name_dir = sel_make_dir(class_dir, classes[i],
1733                                 &last_class_ino);
1734                 if (IS_ERR(class_name_dir)) {
1735                         rc = PTR_ERR(class_name_dir);
1736                         goto out;
1737                 }
1738
1739                 /* i+1 since class values are 1-indexed */
1740                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1741                                 class_name_dir);
1742                 if (rc)
1743                         goto out;
1744         }
1745         rc = 0;
1746 out:
1747         for (i = 0; i < nclasses; i++)
1748                 kfree(classes[i]);
1749         kfree(classes);
1750         return rc;
1751 }
1752
1753 static int sel_make_policycap(void)
1754 {
1755         unsigned int iter;
1756         struct dentry *dentry = NULL;
1757         struct inode *inode = NULL;
1758
1759         sel_remove_entries(policycap_dir);
1760
1761         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1762                 if (iter < ARRAY_SIZE(policycap_names))
1763                         dentry = d_alloc_name(policycap_dir,
1764                                               policycap_names[iter]);
1765                 else
1766                         dentry = d_alloc_name(policycap_dir, "unknown");
1767
1768                 if (dentry == NULL)
1769                         return -ENOMEM;
1770
1771                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1772                 if (inode == NULL)
1773                         return -ENOMEM;
1774
1775                 inode->i_fop = &sel_policycap_ops;
1776                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1777                 d_add(dentry, inode);
1778         }
1779
1780         return 0;
1781 }
1782
1783 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1784                         unsigned long *ino)
1785 {
1786         struct dentry *dentry = d_alloc_name(dir, name);
1787         struct inode *inode;
1788
1789         if (!dentry)
1790                 return ERR_PTR(-ENOMEM);
1791
1792         inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1793         if (!inode) {
1794                 dput(dentry);
1795                 return ERR_PTR(-ENOMEM);
1796         }
1797
1798         inode->i_op = &simple_dir_inode_operations;
1799         inode->i_fop = &simple_dir_operations;
1800         inode->i_ino = ++(*ino);
1801         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1802         inc_nlink(inode);
1803         d_add(dentry, inode);
1804         /* bump link count on parent directory, too */
1805         inc_nlink(dir->d_inode);
1806
1807         return dentry;
1808 }
1809
1810 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1811 {
1812         int ret;
1813         struct dentry *dentry;
1814         struct inode *inode;
1815         struct inode_security_struct *isec;
1816
1817         static struct tree_descr selinux_files[] = {
1818                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1819                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1820                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1821                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1822                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1823                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1824                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1825                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1826                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1827                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1828                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1829                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1830                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1831                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1832                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1833                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1834                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUSR},
1835                 /* last one */ {""}
1836         };
1837         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1838         if (ret)
1839                 goto err;
1840
1841         bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino);
1842         if (IS_ERR(bool_dir)) {
1843                 ret = PTR_ERR(bool_dir);
1844                 bool_dir = NULL;
1845                 goto err;
1846         }
1847
1848         ret = -ENOMEM;
1849         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1850         if (!dentry)
1851                 goto err;
1852
1853         ret = -ENOMEM;
1854         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1855         if (!inode)
1856                 goto err;
1857
1858         inode->i_ino = ++sel_last_ino;
1859         isec = (struct inode_security_struct *)inode->i_security;
1860         isec->sid = SECINITSID_DEVNULL;
1861         isec->sclass = SECCLASS_CHR_FILE;
1862         isec->initialized = 1;
1863
1864         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1865         d_add(dentry, inode);
1866         selinux_null = dentry;
1867
1868         dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino);
1869         if (IS_ERR(dentry)) {
1870                 ret = PTR_ERR(dentry);
1871                 goto err;
1872         }
1873
1874         ret = sel_make_avc_files(dentry);
1875         if (ret)
1876                 goto err;
1877
1878         dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino);
1879         if (IS_ERR(dentry)) {
1880                 ret = PTR_ERR(dentry);
1881                 goto err;
1882         }
1883
1884         ret = sel_make_initcon_files(dentry);
1885         if (ret)
1886                 goto err;
1887
1888         class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino);
1889         if (IS_ERR(class_dir)) {
1890                 ret = PTR_ERR(class_dir);
1891                 class_dir = NULL;
1892                 goto err;
1893         }
1894
1895         policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino);
1896         if (IS_ERR(policycap_dir)) {
1897                 ret = PTR_ERR(policycap_dir);
1898                 policycap_dir = NULL;
1899                 goto err;
1900         }
1901         return 0;
1902 err:
1903         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1904                 __func__);
1905         return ret;
1906 }
1907
1908 static struct dentry *sel_mount(struct file_system_type *fs_type,
1909                       int flags, const char *dev_name, void *data)
1910 {
1911         return mount_single(fs_type, flags, data, sel_fill_super);
1912 }
1913
1914 static struct file_system_type sel_fs_type = {
1915         .name           = "selinuxfs",
1916         .mount          = sel_mount,
1917         .kill_sb        = kill_litter_super,
1918 };
1919
1920 struct vfsmount *selinuxfs_mount;
1921 static struct kobject *selinuxfs_kobj;
1922
1923 static int __init init_sel_fs(void)
1924 {
1925         int err;
1926
1927         if (!selinux_enabled)
1928                 return 0;
1929
1930         selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj);
1931         if (!selinuxfs_kobj)
1932                 return -ENOMEM;
1933
1934         err = register_filesystem(&sel_fs_type);
1935         if (err) {
1936                 kobject_put(selinuxfs_kobj);
1937                 return err;
1938         }
1939
1940         selinuxfs_mount = kern_mount(&sel_fs_type);
1941         if (IS_ERR(selinuxfs_mount)) {
1942                 printk(KERN_ERR "selinuxfs:  could not mount!\n");
1943                 err = PTR_ERR(selinuxfs_mount);
1944                 selinuxfs_mount = NULL;
1945         }
1946
1947         return err;
1948 }
1949
1950 __initcall(init_sel_fs);
1951
1952 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1953 void exit_sel_fs(void)
1954 {
1955         kobject_put(selinuxfs_kobj);
1956         kern_unmount(selinuxfs_mount);
1957         unregister_filesystem(&sel_fs_type);
1958 }
1959 #endif