Merge git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac
[platform/adaptation/renesas_rcar/renesas_kernel.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                         from_kuid(&init_user_ns, 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                         from_kuid(&init_user_ns, 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_DONTEXPAND | VM_DONTDUMP;
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         .llseek         = generic_file_llseek,
500 };
501
502 static ssize_t sel_write_load(struct file *file, const char __user *buf,
503                               size_t count, loff_t *ppos)
504
505 {
506         ssize_t length;
507         void *data = NULL;
508
509         mutex_lock(&sel_mutex);
510
511         length = task_has_security(current, SECURITY__LOAD_POLICY);
512         if (length)
513                 goto out;
514
515         /* No partial writes. */
516         length = -EINVAL;
517         if (*ppos != 0)
518                 goto out;
519
520         length = -EFBIG;
521         if (count > 64 * 1024 * 1024)
522                 goto out;
523
524         length = -ENOMEM;
525         data = vmalloc(count);
526         if (!data)
527                 goto out;
528
529         length = -EFAULT;
530         if (copy_from_user(data, buf, count) != 0)
531                 goto out;
532
533         length = security_load_policy(data, count);
534         if (length)
535                 goto out;
536
537         length = sel_make_bools();
538         if (length)
539                 goto out1;
540
541         length = sel_make_classes();
542         if (length)
543                 goto out1;
544
545         length = sel_make_policycap();
546         if (length)
547                 goto out1;
548
549         length = count;
550
551 out1:
552         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
553                 "policy loaded auid=%u ses=%u",
554                 from_kuid(&init_user_ns, audit_get_loginuid(current)),
555                 audit_get_sessionid(current));
556 out:
557         mutex_unlock(&sel_mutex);
558         vfree(data);
559         return length;
560 }
561
562 static const struct file_operations sel_load_ops = {
563         .write          = sel_write_load,
564         .llseek         = generic_file_llseek,
565 };
566
567 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
568 {
569         char *canon = NULL;
570         u32 sid, len;
571         ssize_t length;
572
573         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
574         if (length)
575                 goto out;
576
577         length = security_context_to_sid(buf, size, &sid);
578         if (length)
579                 goto out;
580
581         length = security_sid_to_context(sid, &canon, &len);
582         if (length)
583                 goto out;
584
585         length = -ERANGE;
586         if (len > SIMPLE_TRANSACTION_LIMIT) {
587                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
588                         "payload max\n", __func__, len);
589                 goto out;
590         }
591
592         memcpy(buf, canon, len);
593         length = len;
594 out:
595         kfree(canon);
596         return length;
597 }
598
599 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
600                                      size_t count, loff_t *ppos)
601 {
602         char tmpbuf[TMPBUFLEN];
603         ssize_t length;
604
605         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
606         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
607 }
608
609 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
610                                       size_t count, loff_t *ppos)
611 {
612         char *page = NULL;
613         ssize_t length;
614         unsigned int new_value;
615
616         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
617         if (length)
618                 goto out;
619
620         length = -ENOMEM;
621         if (count >= PAGE_SIZE)
622                 goto out;
623
624         /* No partial writes. */
625         length = -EINVAL;
626         if (*ppos != 0)
627                 goto out;
628
629         length = -ENOMEM;
630         page = (char *)get_zeroed_page(GFP_KERNEL);
631         if (!page)
632                 goto out;
633
634         length = -EFAULT;
635         if (copy_from_user(page, buf, count))
636                 goto out;
637
638         length = -EINVAL;
639         if (sscanf(page, "%u", &new_value) != 1)
640                 goto out;
641
642         selinux_checkreqprot = new_value ? 1 : 0;
643         length = count;
644 out:
645         free_page((unsigned long) page);
646         return length;
647 }
648 static const struct file_operations sel_checkreqprot_ops = {
649         .read           = sel_read_checkreqprot,
650         .write          = sel_write_checkreqprot,
651         .llseek         = generic_file_llseek,
652 };
653
654 /*
655  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
656  */
657 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
658 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
659 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
660 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
661 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
662
663 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
664         [SEL_ACCESS] = sel_write_access,
665         [SEL_CREATE] = sel_write_create,
666         [SEL_RELABEL] = sel_write_relabel,
667         [SEL_USER] = sel_write_user,
668         [SEL_MEMBER] = sel_write_member,
669         [SEL_CONTEXT] = sel_write_context,
670 };
671
672 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
673 {
674         ino_t ino = file->f_path.dentry->d_inode->i_ino;
675         char *data;
676         ssize_t rv;
677
678         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
679                 return -EINVAL;
680
681         data = simple_transaction_get(file, buf, size);
682         if (IS_ERR(data))
683                 return PTR_ERR(data);
684
685         rv = write_op[ino](file, data, size);
686         if (rv > 0) {
687                 simple_transaction_set(file, rv);
688                 rv = size;
689         }
690         return rv;
691 }
692
693 static const struct file_operations transaction_ops = {
694         .write          = selinux_transaction_write,
695         .read           = simple_transaction_read,
696         .release        = simple_transaction_release,
697         .llseek         = generic_file_llseek,
698 };
699
700 /*
701  * payload - write methods
702  * If the method has a response, the response should be put in buf,
703  * and the length returned.  Otherwise return 0 or and -error.
704  */
705
706 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
707 {
708         char *scon = NULL, *tcon = NULL;
709         u32 ssid, tsid;
710         u16 tclass;
711         struct av_decision avd;
712         ssize_t length;
713
714         length = task_has_security(current, SECURITY__COMPUTE_AV);
715         if (length)
716                 goto out;
717
718         length = -ENOMEM;
719         scon = kzalloc(size + 1, GFP_KERNEL);
720         if (!scon)
721                 goto out;
722
723         length = -ENOMEM;
724         tcon = kzalloc(size + 1, GFP_KERNEL);
725         if (!tcon)
726                 goto out;
727
728         length = -EINVAL;
729         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
730                 goto out;
731
732         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
733         if (length)
734                 goto out;
735
736         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
737         if (length)
738                 goto out;
739
740         security_compute_av_user(ssid, tsid, tclass, &avd);
741
742         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
743                           "%x %x %x %x %u %x",
744                           avd.allowed, 0xffffffff,
745                           avd.auditallow, avd.auditdeny,
746                           avd.seqno, avd.flags);
747 out:
748         kfree(tcon);
749         kfree(scon);
750         return length;
751 }
752
753 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
754 {
755         char *scon = NULL, *tcon = NULL;
756         char *namebuf = NULL, *objname = NULL;
757         u32 ssid, tsid, newsid;
758         u16 tclass;
759         ssize_t length;
760         char *newcon = NULL;
761         u32 len;
762         int nargs;
763
764         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
765         if (length)
766                 goto out;
767
768         length = -ENOMEM;
769         scon = kzalloc(size + 1, GFP_KERNEL);
770         if (!scon)
771                 goto out;
772
773         length = -ENOMEM;
774         tcon = kzalloc(size + 1, GFP_KERNEL);
775         if (!tcon)
776                 goto out;
777
778         length = -ENOMEM;
779         namebuf = kzalloc(size + 1, GFP_KERNEL);
780         if (!namebuf)
781                 goto out;
782
783         length = -EINVAL;
784         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
785         if (nargs < 3 || nargs > 4)
786                 goto out;
787         if (nargs == 4) {
788                 /*
789                  * If and when the name of new object to be queried contains
790                  * either whitespace or multibyte characters, they shall be
791                  * encoded based on the percentage-encoding rule.
792                  * If not encoded, the sscanf logic picks up only left-half
793                  * of the supplied name; splitted by a whitespace unexpectedly.
794                  */
795                 char   *r, *w;
796                 int     c1, c2;
797
798                 r = w = namebuf;
799                 do {
800                         c1 = *r++;
801                         if (c1 == '+')
802                                 c1 = ' ';
803                         else if (c1 == '%') {
804                                 c1 = hex_to_bin(*r++);
805                                 if (c1 < 0)
806                                         goto out;
807                                 c2 = hex_to_bin(*r++);
808                                 if (c2 < 0)
809                                         goto out;
810                                 c1 = (c1 << 4) | c2;
811                         }
812                         *w++ = c1;
813                 } while (c1 != '\0');
814
815                 objname = namebuf;
816         }
817
818         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
819         if (length)
820                 goto out;
821
822         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
823         if (length)
824                 goto out;
825
826         length = security_transition_sid_user(ssid, tsid, tclass,
827                                               objname, &newsid);
828         if (length)
829                 goto out;
830
831         length = security_sid_to_context(newsid, &newcon, &len);
832         if (length)
833                 goto out;
834
835         length = -ERANGE;
836         if (len > SIMPLE_TRANSACTION_LIMIT) {
837                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
838                         "payload max\n", __func__, len);
839                 goto out;
840         }
841
842         memcpy(buf, newcon, len);
843         length = len;
844 out:
845         kfree(newcon);
846         kfree(namebuf);
847         kfree(tcon);
848         kfree(scon);
849         return length;
850 }
851
852 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
853 {
854         char *scon = NULL, *tcon = NULL;
855         u32 ssid, tsid, newsid;
856         u16 tclass;
857         ssize_t length;
858         char *newcon = NULL;
859         u32 len;
860
861         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
862         if (length)
863                 goto out;
864
865         length = -ENOMEM;
866         scon = kzalloc(size + 1, GFP_KERNEL);
867         if (!scon)
868                 goto out;
869
870         length = -ENOMEM;
871         tcon = kzalloc(size + 1, GFP_KERNEL);
872         if (!tcon)
873                 goto out;
874
875         length = -EINVAL;
876         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
877                 goto out;
878
879         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
880         if (length)
881                 goto out;
882
883         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
884         if (length)
885                 goto out;
886
887         length = security_change_sid(ssid, tsid, tclass, &newsid);
888         if (length)
889                 goto out;
890
891         length = security_sid_to_context(newsid, &newcon, &len);
892         if (length)
893                 goto out;
894
895         length = -ERANGE;
896         if (len > SIMPLE_TRANSACTION_LIMIT)
897                 goto out;
898
899         memcpy(buf, newcon, len);
900         length = len;
901 out:
902         kfree(newcon);
903         kfree(tcon);
904         kfree(scon);
905         return length;
906 }
907
908 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
909 {
910         char *con = NULL, *user = NULL, *ptr;
911         u32 sid, *sids = NULL;
912         ssize_t length;
913         char *newcon;
914         int i, rc;
915         u32 len, nsids;
916
917         length = task_has_security(current, SECURITY__COMPUTE_USER);
918         if (length)
919                 goto out;
920
921         length = -ENOMEM;
922         con = kzalloc(size + 1, GFP_KERNEL);
923         if (!con)
924                 goto out;
925
926         length = -ENOMEM;
927         user = kzalloc(size + 1, GFP_KERNEL);
928         if (!user)
929                 goto out;
930
931         length = -EINVAL;
932         if (sscanf(buf, "%s %s", con, user) != 2)
933                 goto out;
934
935         length = security_context_to_sid(con, strlen(con) + 1, &sid);
936         if (length)
937                 goto out;
938
939         length = security_get_user_sids(sid, user, &sids, &nsids);
940         if (length)
941                 goto out;
942
943         length = sprintf(buf, "%u", nsids) + 1;
944         ptr = buf + length;
945         for (i = 0; i < nsids; i++) {
946                 rc = security_sid_to_context(sids[i], &newcon, &len);
947                 if (rc) {
948                         length = rc;
949                         goto out;
950                 }
951                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
952                         kfree(newcon);
953                         length = -ERANGE;
954                         goto out;
955                 }
956                 memcpy(ptr, newcon, len);
957                 kfree(newcon);
958                 ptr += len;
959                 length += len;
960         }
961 out:
962         kfree(sids);
963         kfree(user);
964         kfree(con);
965         return length;
966 }
967
968 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
969 {
970         char *scon = NULL, *tcon = NULL;
971         u32 ssid, tsid, newsid;
972         u16 tclass;
973         ssize_t length;
974         char *newcon = NULL;
975         u32 len;
976
977         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
978         if (length)
979                 goto out;
980
981         length = -ENOMEM;
982         scon = kzalloc(size + 1, GFP_KERNEL);
983         if (!scon)
984                 goto out;
985
986         length = -ENOMEM;
987         tcon = kzalloc(size + 1, GFP_KERNEL);
988         if (!tcon)
989                 goto out;
990
991         length = -EINVAL;
992         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
993                 goto out;
994
995         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
996         if (length)
997                 goto out;
998
999         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
1000         if (length)
1001                 goto out;
1002
1003         length = security_member_sid(ssid, tsid, tclass, &newsid);
1004         if (length)
1005                 goto out;
1006
1007         length = security_sid_to_context(newsid, &newcon, &len);
1008         if (length)
1009                 goto out;
1010
1011         length = -ERANGE;
1012         if (len > SIMPLE_TRANSACTION_LIMIT) {
1013                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
1014                         "payload max\n", __func__, len);
1015                 goto out;
1016         }
1017
1018         memcpy(buf, newcon, len);
1019         length = len;
1020 out:
1021         kfree(newcon);
1022         kfree(tcon);
1023         kfree(scon);
1024         return length;
1025 }
1026
1027 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1028 {
1029         struct inode *ret = new_inode(sb);
1030
1031         if (ret) {
1032                 ret->i_mode = mode;
1033                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
1034         }
1035         return ret;
1036 }
1037
1038 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1039                              size_t count, loff_t *ppos)
1040 {
1041         char *page = NULL;
1042         ssize_t length;
1043         ssize_t ret;
1044         int cur_enforcing;
1045         struct inode *inode = filep->f_path.dentry->d_inode;
1046         unsigned index = inode->i_ino & SEL_INO_MASK;
1047         const char *name = filep->f_path.dentry->d_name.name;
1048
1049         mutex_lock(&sel_mutex);
1050
1051         ret = -EINVAL;
1052         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1053                 goto out;
1054
1055         ret = -ENOMEM;
1056         page = (char *)get_zeroed_page(GFP_KERNEL);
1057         if (!page)
1058                 goto out;
1059
1060         cur_enforcing = security_get_bool_value(index);
1061         if (cur_enforcing < 0) {
1062                 ret = cur_enforcing;
1063                 goto out;
1064         }
1065         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1066                           bool_pending_values[index]);
1067         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1068 out:
1069         mutex_unlock(&sel_mutex);
1070         free_page((unsigned long)page);
1071         return ret;
1072 }
1073
1074 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1075                               size_t count, loff_t *ppos)
1076 {
1077         char *page = NULL;
1078         ssize_t length;
1079         int new_value;
1080         struct inode *inode = filep->f_path.dentry->d_inode;
1081         unsigned index = inode->i_ino & SEL_INO_MASK;
1082         const char *name = filep->f_path.dentry->d_name.name;
1083
1084         mutex_lock(&sel_mutex);
1085
1086         length = task_has_security(current, SECURITY__SETBOOL);
1087         if (length)
1088                 goto out;
1089
1090         length = -EINVAL;
1091         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1092                 goto out;
1093
1094         length = -ENOMEM;
1095         if (count >= PAGE_SIZE)
1096                 goto out;
1097
1098         /* No partial writes. */
1099         length = -EINVAL;
1100         if (*ppos != 0)
1101                 goto out;
1102
1103         length = -ENOMEM;
1104         page = (char *)get_zeroed_page(GFP_KERNEL);
1105         if (!page)
1106                 goto out;
1107
1108         length = -EFAULT;
1109         if (copy_from_user(page, buf, count))
1110                 goto out;
1111
1112         length = -EINVAL;
1113         if (sscanf(page, "%d", &new_value) != 1)
1114                 goto out;
1115
1116         if (new_value)
1117                 new_value = 1;
1118
1119         bool_pending_values[index] = new_value;
1120         length = count;
1121
1122 out:
1123         mutex_unlock(&sel_mutex);
1124         free_page((unsigned long) page);
1125         return length;
1126 }
1127
1128 static const struct file_operations sel_bool_ops = {
1129         .read           = sel_read_bool,
1130         .write          = sel_write_bool,
1131         .llseek         = generic_file_llseek,
1132 };
1133
1134 static ssize_t sel_commit_bools_write(struct file *filep,
1135                                       const char __user *buf,
1136                                       size_t count, loff_t *ppos)
1137 {
1138         char *page = NULL;
1139         ssize_t length;
1140         int new_value;
1141
1142         mutex_lock(&sel_mutex);
1143
1144         length = task_has_security(current, SECURITY__SETBOOL);
1145         if (length)
1146                 goto out;
1147
1148         length = -ENOMEM;
1149         if (count >= PAGE_SIZE)
1150                 goto out;
1151
1152         /* No partial writes. */
1153         length = -EINVAL;
1154         if (*ppos != 0)
1155                 goto out;
1156
1157         length = -ENOMEM;
1158         page = (char *)get_zeroed_page(GFP_KERNEL);
1159         if (!page)
1160                 goto out;
1161
1162         length = -EFAULT;
1163         if (copy_from_user(page, buf, count))
1164                 goto out;
1165
1166         length = -EINVAL;
1167         if (sscanf(page, "%d", &new_value) != 1)
1168                 goto out;
1169
1170         length = 0;
1171         if (new_value && bool_pending_values)
1172                 length = security_set_bools(bool_num, bool_pending_values);
1173
1174         if (!length)
1175                 length = count;
1176
1177 out:
1178         mutex_unlock(&sel_mutex);
1179         free_page((unsigned long) page);
1180         return length;
1181 }
1182
1183 static const struct file_operations sel_commit_bools_ops = {
1184         .write          = sel_commit_bools_write,
1185         .llseek         = generic_file_llseek,
1186 };
1187
1188 static void sel_remove_entries(struct dentry *de)
1189 {
1190         struct list_head *node;
1191
1192         spin_lock(&de->d_lock);
1193         node = de->d_subdirs.next;
1194         while (node != &de->d_subdirs) {
1195                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1196
1197                 spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
1198                 list_del_init(node);
1199
1200                 if (d->d_inode) {
1201                         dget_dlock(d);
1202                         spin_unlock(&de->d_lock);
1203                         spin_unlock(&d->d_lock);
1204                         d_delete(d);
1205                         simple_unlink(de->d_inode, d);
1206                         dput(d);
1207                         spin_lock(&de->d_lock);
1208                 } else
1209                         spin_unlock(&d->d_lock);
1210                 node = de->d_subdirs.next;
1211         }
1212
1213         spin_unlock(&de->d_lock);
1214 }
1215
1216 #define BOOL_DIR_NAME "booleans"
1217
1218 static int sel_make_bools(void)
1219 {
1220         int i, ret;
1221         ssize_t len;
1222         struct dentry *dentry = NULL;
1223         struct dentry *dir = bool_dir;
1224         struct inode *inode = NULL;
1225         struct inode_security_struct *isec;
1226         char **names = NULL, *page;
1227         int num;
1228         int *values = NULL;
1229         u32 sid;
1230
1231         /* remove any existing files */
1232         for (i = 0; i < bool_num; i++)
1233                 kfree(bool_pending_names[i]);
1234         kfree(bool_pending_names);
1235         kfree(bool_pending_values);
1236         bool_num = 0;
1237         bool_pending_names = NULL;
1238         bool_pending_values = NULL;
1239
1240         sel_remove_entries(dir);
1241
1242         ret = -ENOMEM;
1243         page = (char *)get_zeroed_page(GFP_KERNEL);
1244         if (!page)
1245                 goto out;
1246
1247         ret = security_get_bools(&num, &names, &values);
1248         if (ret)
1249                 goto out;
1250
1251         for (i = 0; i < num; i++) {
1252                 ret = -ENOMEM;
1253                 dentry = d_alloc_name(dir, names[i]);
1254                 if (!dentry)
1255                         goto out;
1256
1257                 ret = -ENOMEM;
1258                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1259                 if (!inode)
1260                         goto out;
1261
1262                 ret = -ENAMETOOLONG;
1263                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1264                 if (len >= PAGE_SIZE)
1265                         goto out;
1266
1267                 isec = (struct inode_security_struct *)inode->i_security;
1268                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1269                 if (ret)
1270                         goto out;
1271
1272                 isec->sid = sid;
1273                 isec->initialized = 1;
1274                 inode->i_fop = &sel_bool_ops;
1275                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1276                 d_add(dentry, inode);
1277         }
1278         bool_num = num;
1279         bool_pending_names = names;
1280         bool_pending_values = values;
1281
1282         free_page((unsigned long)page);
1283         return 0;
1284 out:
1285         free_page((unsigned long)page);
1286
1287         if (names) {
1288                 for (i = 0; i < num; i++)
1289                         kfree(names[i]);
1290                 kfree(names);
1291         }
1292         kfree(values);
1293         sel_remove_entries(dir);
1294
1295         return ret;
1296 }
1297
1298 #define NULL_FILE_NAME "null"
1299
1300 struct path selinux_null;
1301
1302 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1303                                             size_t count, loff_t *ppos)
1304 {
1305         char tmpbuf[TMPBUFLEN];
1306         ssize_t length;
1307
1308         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1309         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1310 }
1311
1312 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1313                                              const char __user *buf,
1314                                              size_t count, loff_t *ppos)
1315
1316 {
1317         char *page = NULL;
1318         ssize_t ret;
1319         int new_value;
1320
1321         ret = task_has_security(current, SECURITY__SETSECPARAM);
1322         if (ret)
1323                 goto out;
1324
1325         ret = -ENOMEM;
1326         if (count >= PAGE_SIZE)
1327                 goto out;
1328
1329         /* No partial writes. */
1330         ret = -EINVAL;
1331         if (*ppos != 0)
1332                 goto out;
1333
1334         ret = -ENOMEM;
1335         page = (char *)get_zeroed_page(GFP_KERNEL);
1336         if (!page)
1337                 goto out;
1338
1339         ret = -EFAULT;
1340         if (copy_from_user(page, buf, count))
1341                 goto out;
1342
1343         ret = -EINVAL;
1344         if (sscanf(page, "%u", &new_value) != 1)
1345                 goto out;
1346
1347         avc_cache_threshold = new_value;
1348
1349         ret = count;
1350 out:
1351         free_page((unsigned long)page);
1352         return ret;
1353 }
1354
1355 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1356                                        size_t count, loff_t *ppos)
1357 {
1358         char *page;
1359         ssize_t length;
1360
1361         page = (char *)__get_free_page(GFP_KERNEL);
1362         if (!page)
1363                 return -ENOMEM;
1364
1365         length = avc_get_hash_stats(page);
1366         if (length >= 0)
1367                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1368         free_page((unsigned long)page);
1369
1370         return length;
1371 }
1372
1373 static const struct file_operations sel_avc_cache_threshold_ops = {
1374         .read           = sel_read_avc_cache_threshold,
1375         .write          = sel_write_avc_cache_threshold,
1376         .llseek         = generic_file_llseek,
1377 };
1378
1379 static const struct file_operations sel_avc_hash_stats_ops = {
1380         .read           = sel_read_avc_hash_stats,
1381         .llseek         = generic_file_llseek,
1382 };
1383
1384 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1385 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1386 {
1387         int cpu;
1388
1389         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1390                 if (!cpu_possible(cpu))
1391                         continue;
1392                 *idx = cpu + 1;
1393                 return &per_cpu(avc_cache_stats, cpu);
1394         }
1395         return NULL;
1396 }
1397
1398 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1399 {
1400         loff_t n = *pos - 1;
1401
1402         if (*pos == 0)
1403                 return SEQ_START_TOKEN;
1404
1405         return sel_avc_get_stat_idx(&n);
1406 }
1407
1408 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1409 {
1410         return sel_avc_get_stat_idx(pos);
1411 }
1412
1413 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1414 {
1415         struct avc_cache_stats *st = v;
1416
1417         if (v == SEQ_START_TOKEN)
1418                 seq_printf(seq, "lookups hits misses allocations reclaims "
1419                            "frees\n");
1420         else {
1421                 unsigned int lookups = st->lookups;
1422                 unsigned int misses = st->misses;
1423                 unsigned int hits = lookups - misses;
1424                 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1425                            hits, misses, st->allocations,
1426                            st->reclaims, st->frees);
1427         }
1428         return 0;
1429 }
1430
1431 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1432 { }
1433
1434 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1435         .start          = sel_avc_stats_seq_start,
1436         .next           = sel_avc_stats_seq_next,
1437         .show           = sel_avc_stats_seq_show,
1438         .stop           = sel_avc_stats_seq_stop,
1439 };
1440
1441 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1442 {
1443         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1444 }
1445
1446 static const struct file_operations sel_avc_cache_stats_ops = {
1447         .open           = sel_open_avc_cache_stats,
1448         .read           = seq_read,
1449         .llseek         = seq_lseek,
1450         .release        = seq_release,
1451 };
1452 #endif
1453
1454 static int sel_make_avc_files(struct dentry *dir)
1455 {
1456         int i;
1457         static struct tree_descr files[] = {
1458                 { "cache_threshold",
1459                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1460                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1461 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1462                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1463 #endif
1464         };
1465
1466         for (i = 0; i < ARRAY_SIZE(files); i++) {
1467                 struct inode *inode;
1468                 struct dentry *dentry;
1469
1470                 dentry = d_alloc_name(dir, files[i].name);
1471                 if (!dentry)
1472                         return -ENOMEM;
1473
1474                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1475                 if (!inode)
1476                         return -ENOMEM;
1477
1478                 inode->i_fop = files[i].ops;
1479                 inode->i_ino = ++sel_last_ino;
1480                 d_add(dentry, inode);
1481         }
1482
1483         return 0;
1484 }
1485
1486 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1487                                 size_t count, loff_t *ppos)
1488 {
1489         struct inode *inode;
1490         char *con;
1491         u32 sid, len;
1492         ssize_t ret;
1493
1494         inode = file->f_path.dentry->d_inode;
1495         sid = inode->i_ino&SEL_INO_MASK;
1496         ret = security_sid_to_context(sid, &con, &len);
1497         if (ret)
1498                 return ret;
1499
1500         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1501         kfree(con);
1502         return ret;
1503 }
1504
1505 static const struct file_operations sel_initcon_ops = {
1506         .read           = sel_read_initcon,
1507         .llseek         = generic_file_llseek,
1508 };
1509
1510 static int sel_make_initcon_files(struct dentry *dir)
1511 {
1512         int i;
1513
1514         for (i = 1; i <= SECINITSID_NUM; i++) {
1515                 struct inode *inode;
1516                 struct dentry *dentry;
1517                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1518                 if (!dentry)
1519                         return -ENOMEM;
1520
1521                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1522                 if (!inode)
1523                         return -ENOMEM;
1524
1525                 inode->i_fop = &sel_initcon_ops;
1526                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1527                 d_add(dentry, inode);
1528         }
1529
1530         return 0;
1531 }
1532
1533 static inline unsigned long sel_class_to_ino(u16 class)
1534 {
1535         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1536 }
1537
1538 static inline u16 sel_ino_to_class(unsigned long ino)
1539 {
1540         return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1541 }
1542
1543 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1544 {
1545         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1546 }
1547
1548 static inline u32 sel_ino_to_perm(unsigned long ino)
1549 {
1550         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1551 }
1552
1553 static ssize_t sel_read_class(struct file *file, char __user *buf,
1554                                 size_t count, loff_t *ppos)
1555 {
1556         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1557         char res[TMPBUFLEN];
1558         ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1559         return simple_read_from_buffer(buf, count, ppos, res, len);
1560 }
1561
1562 static const struct file_operations sel_class_ops = {
1563         .read           = sel_read_class,
1564         .llseek         = generic_file_llseek,
1565 };
1566
1567 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1568                                 size_t count, loff_t *ppos)
1569 {
1570         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1571         char res[TMPBUFLEN];
1572         ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1573         return simple_read_from_buffer(buf, count, ppos, res, len);
1574 }
1575
1576 static const struct file_operations sel_perm_ops = {
1577         .read           = sel_read_perm,
1578         .llseek         = generic_file_llseek,
1579 };
1580
1581 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1582                                   size_t count, loff_t *ppos)
1583 {
1584         int value;
1585         char tmpbuf[TMPBUFLEN];
1586         ssize_t length;
1587         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1588
1589         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1590         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1591
1592         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1593 }
1594
1595 static const struct file_operations sel_policycap_ops = {
1596         .read           = sel_read_policycap,
1597         .llseek         = generic_file_llseek,
1598 };
1599
1600 static int sel_make_perm_files(char *objclass, int classvalue,
1601                                 struct dentry *dir)
1602 {
1603         int i, rc, nperms;
1604         char **perms;
1605
1606         rc = security_get_permissions(objclass, &perms, &nperms);
1607         if (rc)
1608                 return rc;
1609
1610         for (i = 0; i < nperms; i++) {
1611                 struct inode *inode;
1612                 struct dentry *dentry;
1613
1614                 rc = -ENOMEM;
1615                 dentry = d_alloc_name(dir, perms[i]);
1616                 if (!dentry)
1617                         goto out;
1618
1619                 rc = -ENOMEM;
1620                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1621                 if (!inode)
1622                         goto out;
1623
1624                 inode->i_fop = &sel_perm_ops;
1625                 /* i+1 since perm values are 1-indexed */
1626                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1627                 d_add(dentry, inode);
1628         }
1629         rc = 0;
1630 out:
1631         for (i = 0; i < nperms; i++)
1632                 kfree(perms[i]);
1633         kfree(perms);
1634         return rc;
1635 }
1636
1637 static int sel_make_class_dir_entries(char *classname, int index,
1638                                         struct dentry *dir)
1639 {
1640         struct dentry *dentry = NULL;
1641         struct inode *inode = NULL;
1642         int rc;
1643
1644         dentry = d_alloc_name(dir, "index");
1645         if (!dentry)
1646                 return -ENOMEM;
1647
1648         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1649         if (!inode)
1650                 return -ENOMEM;
1651
1652         inode->i_fop = &sel_class_ops;
1653         inode->i_ino = sel_class_to_ino(index);
1654         d_add(dentry, inode);
1655
1656         dentry = sel_make_dir(dir, "perms", &last_class_ino);
1657         if (IS_ERR(dentry))
1658                 return PTR_ERR(dentry);
1659
1660         rc = sel_make_perm_files(classname, index, dentry);
1661
1662         return rc;
1663 }
1664
1665 static void sel_remove_classes(void)
1666 {
1667         struct list_head *class_node;
1668
1669         list_for_each(class_node, &class_dir->d_subdirs) {
1670                 struct dentry *class_subdir = list_entry(class_node,
1671                                         struct dentry, d_u.d_child);
1672                 struct list_head *class_subdir_node;
1673
1674                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1675                         struct dentry *d = list_entry(class_subdir_node,
1676                                                 struct dentry, d_u.d_child);
1677
1678                         if (d->d_inode)
1679                                 if (d->d_inode->i_mode & S_IFDIR)
1680                                         sel_remove_entries(d);
1681                 }
1682
1683                 sel_remove_entries(class_subdir);
1684         }
1685
1686         sel_remove_entries(class_dir);
1687 }
1688
1689 static int sel_make_classes(void)
1690 {
1691         int rc, nclasses, i;
1692         char **classes;
1693
1694         /* delete any existing entries */
1695         sel_remove_classes();
1696
1697         rc = security_get_classes(&classes, &nclasses);
1698         if (rc)
1699                 return rc;
1700
1701         /* +2 since classes are 1-indexed */
1702         last_class_ino = sel_class_to_ino(nclasses + 2);
1703
1704         for (i = 0; i < nclasses; i++) {
1705                 struct dentry *class_name_dir;
1706
1707                 class_name_dir = sel_make_dir(class_dir, classes[i],
1708                                 &last_class_ino);
1709                 if (IS_ERR(class_name_dir)) {
1710                         rc = PTR_ERR(class_name_dir);
1711                         goto out;
1712                 }
1713
1714                 /* i+1 since class values are 1-indexed */
1715                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1716                                 class_name_dir);
1717                 if (rc)
1718                         goto out;
1719         }
1720         rc = 0;
1721 out:
1722         for (i = 0; i < nclasses; i++)
1723                 kfree(classes[i]);
1724         kfree(classes);
1725         return rc;
1726 }
1727
1728 static int sel_make_policycap(void)
1729 {
1730         unsigned int iter;
1731         struct dentry *dentry = NULL;
1732         struct inode *inode = NULL;
1733
1734         sel_remove_entries(policycap_dir);
1735
1736         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1737                 if (iter < ARRAY_SIZE(policycap_names))
1738                         dentry = d_alloc_name(policycap_dir,
1739                                               policycap_names[iter]);
1740                 else
1741                         dentry = d_alloc_name(policycap_dir, "unknown");
1742
1743                 if (dentry == NULL)
1744                         return -ENOMEM;
1745
1746                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1747                 if (inode == NULL)
1748                         return -ENOMEM;
1749
1750                 inode->i_fop = &sel_policycap_ops;
1751                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1752                 d_add(dentry, inode);
1753         }
1754
1755         return 0;
1756 }
1757
1758 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1759                         unsigned long *ino)
1760 {
1761         struct dentry *dentry = d_alloc_name(dir, name);
1762         struct inode *inode;
1763
1764         if (!dentry)
1765                 return ERR_PTR(-ENOMEM);
1766
1767         inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1768         if (!inode) {
1769                 dput(dentry);
1770                 return ERR_PTR(-ENOMEM);
1771         }
1772
1773         inode->i_op = &simple_dir_inode_operations;
1774         inode->i_fop = &simple_dir_operations;
1775         inode->i_ino = ++(*ino);
1776         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1777         inc_nlink(inode);
1778         d_add(dentry, inode);
1779         /* bump link count on parent directory, too */
1780         inc_nlink(dir->d_inode);
1781
1782         return dentry;
1783 }
1784
1785 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1786 {
1787         int ret;
1788         struct dentry *dentry;
1789         struct inode *inode;
1790         struct inode_security_struct *isec;
1791
1792         static struct tree_descr selinux_files[] = {
1793                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1794                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1795                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1796                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1797                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1798                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1799                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1800                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1801                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1802                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1803                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1804                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1805                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1806                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1807                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1808                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1809                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1810                 /* last one */ {""}
1811         };
1812         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1813         if (ret)
1814                 goto err;
1815
1816         bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &sel_last_ino);
1817         if (IS_ERR(bool_dir)) {
1818                 ret = PTR_ERR(bool_dir);
1819                 bool_dir = NULL;
1820                 goto err;
1821         }
1822
1823         ret = -ENOMEM;
1824         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1825         if (!dentry)
1826                 goto err;
1827
1828         ret = -ENOMEM;
1829         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1830         if (!inode)
1831                 goto err;
1832
1833         inode->i_ino = ++sel_last_ino;
1834         isec = (struct inode_security_struct *)inode->i_security;
1835         isec->sid = SECINITSID_DEVNULL;
1836         isec->sclass = SECCLASS_CHR_FILE;
1837         isec->initialized = 1;
1838
1839         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1840         d_add(dentry, inode);
1841         selinux_null.dentry = dentry;
1842
1843         dentry = sel_make_dir(sb->s_root, "avc", &sel_last_ino);
1844         if (IS_ERR(dentry)) {
1845                 ret = PTR_ERR(dentry);
1846                 goto err;
1847         }
1848
1849         ret = sel_make_avc_files(dentry);
1850         if (ret)
1851                 goto err;
1852
1853         dentry = sel_make_dir(sb->s_root, "initial_contexts", &sel_last_ino);
1854         if (IS_ERR(dentry)) {
1855                 ret = PTR_ERR(dentry);
1856                 goto err;
1857         }
1858
1859         ret = sel_make_initcon_files(dentry);
1860         if (ret)
1861                 goto err;
1862
1863         class_dir = sel_make_dir(sb->s_root, "class", &sel_last_ino);
1864         if (IS_ERR(class_dir)) {
1865                 ret = PTR_ERR(class_dir);
1866                 class_dir = NULL;
1867                 goto err;
1868         }
1869
1870         policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", &sel_last_ino);
1871         if (IS_ERR(policycap_dir)) {
1872                 ret = PTR_ERR(policycap_dir);
1873                 policycap_dir = NULL;
1874                 goto err;
1875         }
1876         return 0;
1877 err:
1878         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1879                 __func__);
1880         return ret;
1881 }
1882
1883 static struct dentry *sel_mount(struct file_system_type *fs_type,
1884                       int flags, const char *dev_name, void *data)
1885 {
1886         return mount_single(fs_type, flags, data, sel_fill_super);
1887 }
1888
1889 static struct file_system_type sel_fs_type = {
1890         .name           = "selinuxfs",
1891         .mount          = sel_mount,
1892         .kill_sb        = kill_litter_super,
1893 };
1894
1895 struct vfsmount *selinuxfs_mount;
1896 static struct kobject *selinuxfs_kobj;
1897
1898 static int __init init_sel_fs(void)
1899 {
1900         int err;
1901
1902         if (!selinux_enabled)
1903                 return 0;
1904
1905         selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj);
1906         if (!selinuxfs_kobj)
1907                 return -ENOMEM;
1908
1909         err = register_filesystem(&sel_fs_type);
1910         if (err) {
1911                 kobject_put(selinuxfs_kobj);
1912                 return err;
1913         }
1914
1915         selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
1916         if (IS_ERR(selinuxfs_mount)) {
1917                 printk(KERN_ERR "selinuxfs:  could not mount!\n");
1918                 err = PTR_ERR(selinuxfs_mount);
1919                 selinuxfs_mount = NULL;
1920         }
1921
1922         return err;
1923 }
1924
1925 __initcall(init_sel_fs);
1926
1927 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1928 void exit_sel_fs(void)
1929 {
1930         kobject_put(selinuxfs_kobj);
1931         kern_unmount(selinuxfs_mount);
1932         unregister_filesystem(&sel_fs_type);
1933 }
1934 #endif