vfs: fix warning: 'dirent' is used uninitialized in this function
[sfrench/cifs-2.6.git] / security / selinux / selinuxfs.c
1 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
2  *
3  *      Added conditional policy language extensions
4  *
5  *  Updated: Hewlett-Packard <paul.moore@hp.com>
6  *
7  *      Added support for the policy capability bitmap
8  *
9  * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
10  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
11  * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
12  *      This program is free software; you can redistribute it and/or modify
13  *      it under the terms of the GNU General Public License as published by
14  *      the Free Software Foundation, version 2.
15  */
16
17 #include <linux/kernel.h>
18 #include <linux/pagemap.h>
19 #include <linux/slab.h>
20 #include <linux/vmalloc.h>
21 #include <linux/fs.h>
22 #include <linux/mutex.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/security.h>
26 #include <linux/major.h>
27 #include <linux/seq_file.h>
28 #include <linux/percpu.h>
29 #include <linux/audit.h>
30 #include <linux/uaccess.h>
31
32 /* selinuxfs pseudo filesystem for exporting the security policy API.
33    Based on the proc code and the fs/nfsd/nfsctl.c code. */
34
35 #include "flask.h"
36 #include "avc.h"
37 #include "avc_ss.h"
38 #include "security.h"
39 #include "objsec.h"
40 #include "conditional.h"
41
42 /* Policy capability filenames */
43 static char *policycap_names[] = {
44         "network_peer_controls",
45         "open_perms"
46 };
47
48 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
49
50 static int __init checkreqprot_setup(char *str)
51 {
52         unsigned long checkreqprot;
53         if (!strict_strtoul(str, 0, &checkreqprot))
54                 selinux_checkreqprot = checkreqprot ? 1 : 0;
55         return 1;
56 }
57 __setup("checkreqprot=", checkreqprot_setup);
58
59 static DEFINE_MUTEX(sel_mutex);
60
61 /* global data for booleans */
62 static struct dentry *bool_dir;
63 static int bool_num;
64 static char **bool_pending_names;
65 static int *bool_pending_values;
66
67 /* global data for classes */
68 static struct dentry *class_dir;
69 static unsigned long last_class_ino;
70
71 /* global data for policy capabilities */
72 static struct dentry *policycap_dir;
73
74 extern void selnl_notify_setenforce(int val);
75
76 /* Check whether a task is allowed to use a security operation. */
77 static int task_has_security(struct task_struct *tsk,
78                              u32 perms)
79 {
80         const struct task_security_struct *tsec;
81         u32 sid = 0;
82
83         rcu_read_lock();
84         tsec = __task_cred(tsk)->security;
85         if (tsec)
86                 sid = tsec->sid;
87         rcu_read_unlock();
88         if (!tsec)
89                 return -EACCES;
90
91         return avc_has_perm(sid, SECINITSID_SECURITY,
92                             SECCLASS_SECURITY, perms, NULL);
93 }
94
95 enum sel_inos {
96         SEL_ROOT_INO = 2,
97         SEL_LOAD,       /* load policy */
98         SEL_ENFORCE,    /* get or set enforcing status */
99         SEL_CONTEXT,    /* validate context */
100         SEL_ACCESS,     /* compute access decision */
101         SEL_CREATE,     /* compute create labeling decision */
102         SEL_RELABEL,    /* compute relabeling decision */
103         SEL_USER,       /* compute reachable user contexts */
104         SEL_POLICYVERS, /* return policy version for this kernel */
105         SEL_COMMIT_BOOLS, /* commit new boolean values */
106         SEL_MLS,        /* return if MLS policy is enabled */
107         SEL_DISABLE,    /* disable SELinux until next reboot */
108         SEL_MEMBER,     /* compute polyinstantiation membership decision */
109         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
110         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
111         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
112         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
113         SEL_INO_NEXT,   /* The next inode number to use */
114 };
115
116 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
117
118 #define SEL_INITCON_INO_OFFSET          0x01000000
119 #define SEL_BOOL_INO_OFFSET             0x02000000
120 #define SEL_CLASS_INO_OFFSET            0x04000000
121 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
122 #define SEL_INO_MASK                    0x00ffffff
123
124 #define TMPBUFLEN       12
125 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
126                                 size_t count, loff_t *ppos)
127 {
128         char tmpbuf[TMPBUFLEN];
129         ssize_t length;
130
131         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
132         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
133 }
134
135 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
136 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
137                                  size_t count, loff_t *ppos)
138
139 {
140         char *page;
141         ssize_t length;
142         int new_value;
143
144         if (count >= PAGE_SIZE)
145                 return -ENOMEM;
146         if (*ppos != 0) {
147                 /* No partial writes. */
148                 return -EINVAL;
149         }
150         page = (char *)get_zeroed_page(GFP_KERNEL);
151         if (!page)
152                 return -ENOMEM;
153         length = -EFAULT;
154         if (copy_from_user(page, buf, count))
155                 goto out;
156
157         length = -EINVAL;
158         if (sscanf(page, "%d", &new_value) != 1)
159                 goto out;
160
161         if (new_value != selinux_enforcing) {
162                 length = task_has_security(current, SECURITY__SETENFORCE);
163                 if (length)
164                         goto out;
165                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
166                         "enforcing=%d old_enforcing=%d auid=%u ses=%u",
167                         new_value, selinux_enforcing,
168                         audit_get_loginuid(current),
169                         audit_get_sessionid(current));
170                 selinux_enforcing = new_value;
171                 if (selinux_enforcing)
172                         avc_ss_reset(0);
173                 selnl_notify_setenforce(selinux_enforcing);
174         }
175         length = count;
176 out:
177         free_page((unsigned long) page);
178         return length;
179 }
180 #else
181 #define sel_write_enforce NULL
182 #endif
183
184 static const struct file_operations sel_enforce_ops = {
185         .read           = sel_read_enforce,
186         .write          = sel_write_enforce,
187         .llseek         = generic_file_llseek,
188 };
189
190 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
191                                         size_t count, loff_t *ppos)
192 {
193         char tmpbuf[TMPBUFLEN];
194         ssize_t length;
195         ino_t ino = filp->f_path.dentry->d_inode->i_ino;
196         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
197                 security_get_reject_unknown() : !security_get_allow_unknown();
198
199         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
200         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
201 }
202
203 static const struct file_operations sel_handle_unknown_ops = {
204         .read           = sel_read_handle_unknown,
205         .llseek         = generic_file_llseek,
206 };
207
208 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
209 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
210                                  size_t count, loff_t *ppos)
211
212 {
213         char *page;
214         ssize_t length;
215         int new_value;
216         extern int selinux_disable(void);
217
218         if (count >= PAGE_SIZE)
219                 return -ENOMEM;
220         if (*ppos != 0) {
221                 /* No partial writes. */
222                 return -EINVAL;
223         }
224         page = (char *)get_zeroed_page(GFP_KERNEL);
225         if (!page)
226                 return -ENOMEM;
227         length = -EFAULT;
228         if (copy_from_user(page, buf, count))
229                 goto out;
230
231         length = -EINVAL;
232         if (sscanf(page, "%d", &new_value) != 1)
233                 goto out;
234
235         if (new_value) {
236                 length = selinux_disable();
237                 if (length < 0)
238                         goto out;
239                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
240                         "selinux=0 auid=%u ses=%u",
241                         audit_get_loginuid(current),
242                         audit_get_sessionid(current));
243         }
244
245         length = count;
246 out:
247         free_page((unsigned long) page);
248         return length;
249 }
250 #else
251 #define sel_write_disable NULL
252 #endif
253
254 static const struct file_operations sel_disable_ops = {
255         .write          = sel_write_disable,
256         .llseek         = generic_file_llseek,
257 };
258
259 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
260                                    size_t count, loff_t *ppos)
261 {
262         char tmpbuf[TMPBUFLEN];
263         ssize_t length;
264
265         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
266         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
267 }
268
269 static const struct file_operations sel_policyvers_ops = {
270         .read           = sel_read_policyvers,
271         .llseek         = generic_file_llseek,
272 };
273
274 /* declaration for sel_write_load */
275 static int sel_make_bools(void);
276 static int sel_make_classes(void);
277 static int sel_make_policycap(void);
278
279 /* declaration for sel_make_class_dirs */
280 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
281                         unsigned long *ino);
282
283 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
284                                 size_t count, loff_t *ppos)
285 {
286         char tmpbuf[TMPBUFLEN];
287         ssize_t length;
288
289         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
290                            security_mls_enabled());
291         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
292 }
293
294 static const struct file_operations sel_mls_ops = {
295         .read           = sel_read_mls,
296         .llseek         = generic_file_llseek,
297 };
298
299 static ssize_t sel_write_load(struct file *file, const char __user *buf,
300                               size_t count, loff_t *ppos)
301
302 {
303         int ret;
304         ssize_t length;
305         void *data = NULL;
306
307         mutex_lock(&sel_mutex);
308
309         length = task_has_security(current, SECURITY__LOAD_POLICY);
310         if (length)
311                 goto out;
312
313         if (*ppos != 0) {
314                 /* No partial writes. */
315                 length = -EINVAL;
316                 goto out;
317         }
318
319         if ((count > 64 * 1024 * 1024)
320             || (data = vmalloc(count)) == NULL) {
321                 length = -ENOMEM;
322                 goto out;
323         }
324
325         length = -EFAULT;
326         if (copy_from_user(data, buf, count) != 0)
327                 goto out;
328
329         length = security_load_policy(data, count);
330         if (length)
331                 goto out;
332
333         ret = sel_make_bools();
334         if (ret) {
335                 length = ret;
336                 goto out1;
337         }
338
339         ret = sel_make_classes();
340         if (ret) {
341                 length = ret;
342                 goto out1;
343         }
344
345         ret = sel_make_policycap();
346         if (ret)
347                 length = ret;
348         else
349                 length = count;
350
351 out1:
352         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
353                 "policy loaded auid=%u ses=%u",
354                 audit_get_loginuid(current),
355                 audit_get_sessionid(current));
356 out:
357         mutex_unlock(&sel_mutex);
358         vfree(data);
359         return length;
360 }
361
362 static const struct file_operations sel_load_ops = {
363         .write          = sel_write_load,
364         .llseek         = generic_file_llseek,
365 };
366
367 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
368 {
369         char *canon;
370         u32 sid, len;
371         ssize_t length;
372
373         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
374         if (length)
375                 return length;
376
377         length = security_context_to_sid(buf, size, &sid);
378         if (length < 0)
379                 return length;
380
381         length = security_sid_to_context(sid, &canon, &len);
382         if (length < 0)
383                 return length;
384
385         if (len > SIMPLE_TRANSACTION_LIMIT) {
386                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
387                         "payload max\n", __func__, len);
388                 length = -ERANGE;
389                 goto out;
390         }
391
392         memcpy(buf, canon, len);
393         length = len;
394 out:
395         kfree(canon);
396         return length;
397 }
398
399 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
400                                      size_t count, loff_t *ppos)
401 {
402         char tmpbuf[TMPBUFLEN];
403         ssize_t length;
404
405         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
406         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
407 }
408
409 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
410                                       size_t count, loff_t *ppos)
411 {
412         char *page;
413         ssize_t length;
414         unsigned int new_value;
415
416         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
417         if (length)
418                 return length;
419
420         if (count >= PAGE_SIZE)
421                 return -ENOMEM;
422         if (*ppos != 0) {
423                 /* No partial writes. */
424                 return -EINVAL;
425         }
426         page = (char *)get_zeroed_page(GFP_KERNEL);
427         if (!page)
428                 return -ENOMEM;
429         length = -EFAULT;
430         if (copy_from_user(page, buf, count))
431                 goto out;
432
433         length = -EINVAL;
434         if (sscanf(page, "%u", &new_value) != 1)
435                 goto out;
436
437         selinux_checkreqprot = new_value ? 1 : 0;
438         length = count;
439 out:
440         free_page((unsigned long) page);
441         return length;
442 }
443 static const struct file_operations sel_checkreqprot_ops = {
444         .read           = sel_read_checkreqprot,
445         .write          = sel_write_checkreqprot,
446         .llseek         = generic_file_llseek,
447 };
448
449 /*
450  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
451  */
452 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
453 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
454 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
455 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
456 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
457
458 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
459         [SEL_ACCESS] = sel_write_access,
460         [SEL_CREATE] = sel_write_create,
461         [SEL_RELABEL] = sel_write_relabel,
462         [SEL_USER] = sel_write_user,
463         [SEL_MEMBER] = sel_write_member,
464         [SEL_CONTEXT] = sel_write_context,
465 };
466
467 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
468 {
469         ino_t ino = file->f_path.dentry->d_inode->i_ino;
470         char *data;
471         ssize_t rv;
472
473         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
474                 return -EINVAL;
475
476         data = simple_transaction_get(file, buf, size);
477         if (IS_ERR(data))
478                 return PTR_ERR(data);
479
480         rv = write_op[ino](file, data, size);
481         if (rv > 0) {
482                 simple_transaction_set(file, rv);
483                 rv = size;
484         }
485         return rv;
486 }
487
488 static const struct file_operations transaction_ops = {
489         .write          = selinux_transaction_write,
490         .read           = simple_transaction_read,
491         .release        = simple_transaction_release,
492         .llseek         = generic_file_llseek,
493 };
494
495 /*
496  * payload - write methods
497  * If the method has a response, the response should be put in buf,
498  * and the length returned.  Otherwise return 0 or and -error.
499  */
500
501 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
502 {
503         char *scon, *tcon;
504         u32 ssid, tsid;
505         u16 tclass;
506         struct av_decision avd;
507         ssize_t length;
508
509         length = task_has_security(current, SECURITY__COMPUTE_AV);
510         if (length)
511                 return length;
512
513         length = -ENOMEM;
514         scon = kzalloc(size + 1, GFP_KERNEL);
515         if (!scon)
516                 return length;
517
518         tcon = kzalloc(size + 1, GFP_KERNEL);
519         if (!tcon)
520                 goto out;
521
522         length = -EINVAL;
523         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
524                 goto out2;
525
526         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
527         if (length < 0)
528                 goto out2;
529         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
530         if (length < 0)
531                 goto out2;
532
533         security_compute_av_user(ssid, tsid, tclass, &avd);
534
535         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
536                           "%x %x %x %x %u %x",
537                           avd.allowed, 0xffffffff,
538                           avd.auditallow, avd.auditdeny,
539                           avd.seqno, avd.flags);
540 out2:
541         kfree(tcon);
542 out:
543         kfree(scon);
544         return length;
545 }
546
547 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
548 {
549         char *scon, *tcon;
550         u32 ssid, tsid, newsid;
551         u16 tclass;
552         ssize_t length;
553         char *newcon;
554         u32 len;
555
556         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
557         if (length)
558                 return length;
559
560         length = -ENOMEM;
561         scon = kzalloc(size + 1, GFP_KERNEL);
562         if (!scon)
563                 return length;
564
565         tcon = kzalloc(size + 1, GFP_KERNEL);
566         if (!tcon)
567                 goto out;
568
569         length = -EINVAL;
570         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
571                 goto out2;
572
573         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
574         if (length < 0)
575                 goto out2;
576         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
577         if (length < 0)
578                 goto out2;
579
580         length = security_transition_sid_user(ssid, tsid, tclass, &newsid);
581         if (length < 0)
582                 goto out2;
583
584         length = security_sid_to_context(newsid, &newcon, &len);
585         if (length < 0)
586                 goto out2;
587
588         if (len > SIMPLE_TRANSACTION_LIMIT) {
589                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
590                         "payload max\n", __func__, len);
591                 length = -ERANGE;
592                 goto out3;
593         }
594
595         memcpy(buf, newcon, len);
596         length = len;
597 out3:
598         kfree(newcon);
599 out2:
600         kfree(tcon);
601 out:
602         kfree(scon);
603         return length;
604 }
605
606 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
607 {
608         char *scon, *tcon;
609         u32 ssid, tsid, newsid;
610         u16 tclass;
611         ssize_t length;
612         char *newcon;
613         u32 len;
614
615         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
616         if (length)
617                 return length;
618
619         length = -ENOMEM;
620         scon = kzalloc(size + 1, GFP_KERNEL);
621         if (!scon)
622                 return length;
623
624         tcon = kzalloc(size + 1, GFP_KERNEL);
625         if (!tcon)
626                 goto out;
627
628         length = -EINVAL;
629         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
630                 goto out2;
631
632         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
633         if (length < 0)
634                 goto out2;
635         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
636         if (length < 0)
637                 goto out2;
638
639         length = security_change_sid(ssid, tsid, tclass, &newsid);
640         if (length < 0)
641                 goto out2;
642
643         length = security_sid_to_context(newsid, &newcon, &len);
644         if (length < 0)
645                 goto out2;
646
647         if (len > SIMPLE_TRANSACTION_LIMIT) {
648                 length = -ERANGE;
649                 goto out3;
650         }
651
652         memcpy(buf, newcon, len);
653         length = len;
654 out3:
655         kfree(newcon);
656 out2:
657         kfree(tcon);
658 out:
659         kfree(scon);
660         return length;
661 }
662
663 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
664 {
665         char *con, *user, *ptr;
666         u32 sid, *sids;
667         ssize_t length;
668         char *newcon;
669         int i, rc;
670         u32 len, nsids;
671
672         length = task_has_security(current, SECURITY__COMPUTE_USER);
673         if (length)
674                 return length;
675
676         length = -ENOMEM;
677         con = kzalloc(size + 1, GFP_KERNEL);
678         if (!con)
679                 return length;
680
681         user = kzalloc(size + 1, GFP_KERNEL);
682         if (!user)
683                 goto out;
684
685         length = -EINVAL;
686         if (sscanf(buf, "%s %s", con, user) != 2)
687                 goto out2;
688
689         length = security_context_to_sid(con, strlen(con) + 1, &sid);
690         if (length < 0)
691                 goto out2;
692
693         length = security_get_user_sids(sid, user, &sids, &nsids);
694         if (length < 0)
695                 goto out2;
696
697         length = sprintf(buf, "%u", nsids) + 1;
698         ptr = buf + length;
699         for (i = 0; i < nsids; i++) {
700                 rc = security_sid_to_context(sids[i], &newcon, &len);
701                 if (rc) {
702                         length = rc;
703                         goto out3;
704                 }
705                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
706                         kfree(newcon);
707                         length = -ERANGE;
708                         goto out3;
709                 }
710                 memcpy(ptr, newcon, len);
711                 kfree(newcon);
712                 ptr += len;
713                 length += len;
714         }
715 out3:
716         kfree(sids);
717 out2:
718         kfree(user);
719 out:
720         kfree(con);
721         return length;
722 }
723
724 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
725 {
726         char *scon, *tcon;
727         u32 ssid, tsid, newsid;
728         u16 tclass;
729         ssize_t length;
730         char *newcon;
731         u32 len;
732
733         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
734         if (length)
735                 return length;
736
737         length = -ENOMEM;
738         scon = kzalloc(size + 1, GFP_KERNEL);
739         if (!scon)
740                 return length;
741
742         tcon = kzalloc(size + 1, GFP_KERNEL);
743         if (!tcon)
744                 goto out;
745
746         length = -EINVAL;
747         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
748                 goto out2;
749
750         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
751         if (length < 0)
752                 goto out2;
753         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
754         if (length < 0)
755                 goto out2;
756
757         length = security_member_sid(ssid, tsid, tclass, &newsid);
758         if (length < 0)
759                 goto out2;
760
761         length = security_sid_to_context(newsid, &newcon, &len);
762         if (length < 0)
763                 goto out2;
764
765         if (len > SIMPLE_TRANSACTION_LIMIT) {
766                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
767                         "payload max\n", __func__, len);
768                 length = -ERANGE;
769                 goto out3;
770         }
771
772         memcpy(buf, newcon, len);
773         length = len;
774 out3:
775         kfree(newcon);
776 out2:
777         kfree(tcon);
778 out:
779         kfree(scon);
780         return length;
781 }
782
783 static struct inode *sel_make_inode(struct super_block *sb, int mode)
784 {
785         struct inode *ret = new_inode(sb);
786
787         if (ret) {
788                 ret->i_mode = mode;
789                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
790         }
791         return ret;
792 }
793
794 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
795                              size_t count, loff_t *ppos)
796 {
797         char *page = NULL;
798         ssize_t length;
799         ssize_t ret;
800         int cur_enforcing;
801         struct inode *inode = filep->f_path.dentry->d_inode;
802         unsigned index = inode->i_ino & SEL_INO_MASK;
803         const char *name = filep->f_path.dentry->d_name.name;
804
805         mutex_lock(&sel_mutex);
806
807         if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
808                 ret = -EINVAL;
809                 goto out;
810         }
811
812         page = (char *)get_zeroed_page(GFP_KERNEL);
813         if (!page) {
814                 ret = -ENOMEM;
815                 goto out;
816         }
817
818         cur_enforcing = security_get_bool_value(index);
819         if (cur_enforcing < 0) {
820                 ret = cur_enforcing;
821                 goto out;
822         }
823         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
824                           bool_pending_values[index]);
825         ret = simple_read_from_buffer(buf, count, ppos, page, length);
826 out:
827         mutex_unlock(&sel_mutex);
828         if (page)
829                 free_page((unsigned long)page);
830         return ret;
831 }
832
833 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
834                               size_t count, loff_t *ppos)
835 {
836         char *page = NULL;
837         ssize_t length;
838         int new_value;
839         struct inode *inode = filep->f_path.dentry->d_inode;
840         unsigned index = inode->i_ino & SEL_INO_MASK;
841         const char *name = filep->f_path.dentry->d_name.name;
842
843         mutex_lock(&sel_mutex);
844
845         length = task_has_security(current, SECURITY__SETBOOL);
846         if (length)
847                 goto out;
848
849         if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
850                 length = -EINVAL;
851                 goto out;
852         }
853
854         if (count >= PAGE_SIZE) {
855                 length = -ENOMEM;
856                 goto out;
857         }
858
859         if (*ppos != 0) {
860                 /* No partial writes. */
861                 length = -EINVAL;
862                 goto out;
863         }
864         page = (char *)get_zeroed_page(GFP_KERNEL);
865         if (!page) {
866                 length = -ENOMEM;
867                 goto out;
868         }
869
870         length = -EFAULT;
871         if (copy_from_user(page, buf, count))
872                 goto out;
873
874         length = -EINVAL;
875         if (sscanf(page, "%d", &new_value) != 1)
876                 goto out;
877
878         if (new_value)
879                 new_value = 1;
880
881         bool_pending_values[index] = new_value;
882         length = count;
883
884 out:
885         mutex_unlock(&sel_mutex);
886         if (page)
887                 free_page((unsigned long) page);
888         return length;
889 }
890
891 static const struct file_operations sel_bool_ops = {
892         .read           = sel_read_bool,
893         .write          = sel_write_bool,
894         .llseek         = generic_file_llseek,
895 };
896
897 static ssize_t sel_commit_bools_write(struct file *filep,
898                                       const char __user *buf,
899                                       size_t count, loff_t *ppos)
900 {
901         char *page = NULL;
902         ssize_t length;
903         int new_value;
904
905         mutex_lock(&sel_mutex);
906
907         length = task_has_security(current, SECURITY__SETBOOL);
908         if (length)
909                 goto out;
910
911         if (count >= PAGE_SIZE) {
912                 length = -ENOMEM;
913                 goto out;
914         }
915         if (*ppos != 0) {
916                 /* No partial writes. */
917                 goto out;
918         }
919         page = (char *)get_zeroed_page(GFP_KERNEL);
920         if (!page) {
921                 length = -ENOMEM;
922                 goto out;
923         }
924
925         length = -EFAULT;
926         if (copy_from_user(page, buf, count))
927                 goto out;
928
929         length = -EINVAL;
930         if (sscanf(page, "%d", &new_value) != 1)
931                 goto out;
932
933         if (new_value && bool_pending_values)
934                 security_set_bools(bool_num, bool_pending_values);
935
936         length = count;
937
938 out:
939         mutex_unlock(&sel_mutex);
940         if (page)
941                 free_page((unsigned long) page);
942         return length;
943 }
944
945 static const struct file_operations sel_commit_bools_ops = {
946         .write          = sel_commit_bools_write,
947         .llseek         = generic_file_llseek,
948 };
949
950 static void sel_remove_entries(struct dentry *de)
951 {
952         struct list_head *node;
953
954         spin_lock(&dcache_lock);
955         node = de->d_subdirs.next;
956         while (node != &de->d_subdirs) {
957                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
958                 list_del_init(node);
959
960                 if (d->d_inode) {
961                         d = dget_locked(d);
962                         spin_unlock(&dcache_lock);
963                         d_delete(d);
964                         simple_unlink(de->d_inode, d);
965                         dput(d);
966                         spin_lock(&dcache_lock);
967                 }
968                 node = de->d_subdirs.next;
969         }
970
971         spin_unlock(&dcache_lock);
972 }
973
974 #define BOOL_DIR_NAME "booleans"
975
976 static int sel_make_bools(void)
977 {
978         int i, ret = 0;
979         ssize_t len;
980         struct dentry *dentry = NULL;
981         struct dentry *dir = bool_dir;
982         struct inode *inode = NULL;
983         struct inode_security_struct *isec;
984         char **names = NULL, *page;
985         int num;
986         int *values = NULL;
987         u32 sid;
988
989         /* remove any existing files */
990         for (i = 0; i < bool_num; i++)
991                 kfree(bool_pending_names[i]);
992         kfree(bool_pending_names);
993         kfree(bool_pending_values);
994         bool_pending_names = NULL;
995         bool_pending_values = NULL;
996
997         sel_remove_entries(dir);
998
999         page = (char *)get_zeroed_page(GFP_KERNEL);
1000         if (!page)
1001                 return -ENOMEM;
1002
1003         ret = security_get_bools(&num, &names, &values);
1004         if (ret != 0)
1005                 goto out;
1006
1007         for (i = 0; i < num; i++) {
1008                 dentry = d_alloc_name(dir, names[i]);
1009                 if (!dentry) {
1010                         ret = -ENOMEM;
1011                         goto err;
1012                 }
1013                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1014                 if (!inode) {
1015                         ret = -ENOMEM;
1016                         goto err;
1017                 }
1018
1019                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1020                 if (len < 0) {
1021                         ret = -EINVAL;
1022                         goto err;
1023                 } else if (len >= PAGE_SIZE) {
1024                         ret = -ENAMETOOLONG;
1025                         goto err;
1026                 }
1027                 isec = (struct inode_security_struct *)inode->i_security;
1028                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1029                 if (ret)
1030                         goto err;
1031                 isec->sid = sid;
1032                 isec->initialized = 1;
1033                 inode->i_fop = &sel_bool_ops;
1034                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1035                 d_add(dentry, inode);
1036         }
1037         bool_num = num;
1038         bool_pending_names = names;
1039         bool_pending_values = values;
1040 out:
1041         free_page((unsigned long)page);
1042         return ret;
1043 err:
1044         if (names) {
1045                 for (i = 0; i < num; i++)
1046                         kfree(names[i]);
1047                 kfree(names);
1048         }
1049         kfree(values);
1050         sel_remove_entries(dir);
1051         ret = -ENOMEM;
1052         goto out;
1053 }
1054
1055 #define NULL_FILE_NAME "null"
1056
1057 struct dentry *selinux_null;
1058
1059 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1060                                             size_t count, loff_t *ppos)
1061 {
1062         char tmpbuf[TMPBUFLEN];
1063         ssize_t length;
1064
1065         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1066         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1067 }
1068
1069 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1070                                              const char __user *buf,
1071                                              size_t count, loff_t *ppos)
1072
1073 {
1074         char *page;
1075         ssize_t ret;
1076         int new_value;
1077
1078         if (count >= PAGE_SIZE) {
1079                 ret = -ENOMEM;
1080                 goto out;
1081         }
1082
1083         if (*ppos != 0) {
1084                 /* No partial writes. */
1085                 ret = -EINVAL;
1086                 goto out;
1087         }
1088
1089         page = (char *)get_zeroed_page(GFP_KERNEL);
1090         if (!page) {
1091                 ret = -ENOMEM;
1092                 goto out;
1093         }
1094
1095         if (copy_from_user(page, buf, count)) {
1096                 ret = -EFAULT;
1097                 goto out_free;
1098         }
1099
1100         if (sscanf(page, "%u", &new_value) != 1) {
1101                 ret = -EINVAL;
1102                 goto out;
1103         }
1104
1105         if (new_value != avc_cache_threshold) {
1106                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1107                 if (ret)
1108                         goto out_free;
1109                 avc_cache_threshold = new_value;
1110         }
1111         ret = count;
1112 out_free:
1113         free_page((unsigned long)page);
1114 out:
1115         return ret;
1116 }
1117
1118 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1119                                        size_t count, loff_t *ppos)
1120 {
1121         char *page;
1122         ssize_t ret = 0;
1123
1124         page = (char *)__get_free_page(GFP_KERNEL);
1125         if (!page) {
1126                 ret = -ENOMEM;
1127                 goto out;
1128         }
1129         ret = avc_get_hash_stats(page);
1130         if (ret >= 0)
1131                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1132         free_page((unsigned long)page);
1133 out:
1134         return ret;
1135 }
1136
1137 static const struct file_operations sel_avc_cache_threshold_ops = {
1138         .read           = sel_read_avc_cache_threshold,
1139         .write          = sel_write_avc_cache_threshold,
1140         .llseek         = generic_file_llseek,
1141 };
1142
1143 static const struct file_operations sel_avc_hash_stats_ops = {
1144         .read           = sel_read_avc_hash_stats,
1145         .llseek         = generic_file_llseek,
1146 };
1147
1148 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1149 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1150 {
1151         int cpu;
1152
1153         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1154                 if (!cpu_possible(cpu))
1155                         continue;
1156                 *idx = cpu + 1;
1157                 return &per_cpu(avc_cache_stats, cpu);
1158         }
1159         return NULL;
1160 }
1161
1162 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1163 {
1164         loff_t n = *pos - 1;
1165
1166         if (*pos == 0)
1167                 return SEQ_START_TOKEN;
1168
1169         return sel_avc_get_stat_idx(&n);
1170 }
1171
1172 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1173 {
1174         return sel_avc_get_stat_idx(pos);
1175 }
1176
1177 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1178 {
1179         struct avc_cache_stats *st = v;
1180
1181         if (v == SEQ_START_TOKEN)
1182                 seq_printf(seq, "lookups hits misses allocations reclaims "
1183                            "frees\n");
1184         else
1185                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1186                            st->hits, st->misses, st->allocations,
1187                            st->reclaims, st->frees);
1188         return 0;
1189 }
1190
1191 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1192 { }
1193
1194 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1195         .start          = sel_avc_stats_seq_start,
1196         .next           = sel_avc_stats_seq_next,
1197         .show           = sel_avc_stats_seq_show,
1198         .stop           = sel_avc_stats_seq_stop,
1199 };
1200
1201 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1202 {
1203         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1204 }
1205
1206 static const struct file_operations sel_avc_cache_stats_ops = {
1207         .open           = sel_open_avc_cache_stats,
1208         .read           = seq_read,
1209         .llseek         = seq_lseek,
1210         .release        = seq_release,
1211 };
1212 #endif
1213
1214 static int sel_make_avc_files(struct dentry *dir)
1215 {
1216         int i, ret = 0;
1217         static struct tree_descr files[] = {
1218                 { "cache_threshold",
1219                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1220                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1221 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1222                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1223 #endif
1224         };
1225
1226         for (i = 0; i < ARRAY_SIZE(files); i++) {
1227                 struct inode *inode;
1228                 struct dentry *dentry;
1229
1230                 dentry = d_alloc_name(dir, files[i].name);
1231                 if (!dentry) {
1232                         ret = -ENOMEM;
1233                         goto out;
1234                 }
1235
1236                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1237                 if (!inode) {
1238                         ret = -ENOMEM;
1239                         goto out;
1240                 }
1241                 inode->i_fop = files[i].ops;
1242                 inode->i_ino = ++sel_last_ino;
1243                 d_add(dentry, inode);
1244         }
1245 out:
1246         return ret;
1247 }
1248
1249 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1250                                 size_t count, loff_t *ppos)
1251 {
1252         struct inode *inode;
1253         char *con;
1254         u32 sid, len;
1255         ssize_t ret;
1256
1257         inode = file->f_path.dentry->d_inode;
1258         sid = inode->i_ino&SEL_INO_MASK;
1259         ret = security_sid_to_context(sid, &con, &len);
1260         if (ret < 0)
1261                 return ret;
1262
1263         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1264         kfree(con);
1265         return ret;
1266 }
1267
1268 static const struct file_operations sel_initcon_ops = {
1269         .read           = sel_read_initcon,
1270         .llseek         = generic_file_llseek,
1271 };
1272
1273 static int sel_make_initcon_files(struct dentry *dir)
1274 {
1275         int i, ret = 0;
1276
1277         for (i = 1; i <= SECINITSID_NUM; i++) {
1278                 struct inode *inode;
1279                 struct dentry *dentry;
1280                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1281                 if (!dentry) {
1282                         ret = -ENOMEM;
1283                         goto out;
1284                 }
1285
1286                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1287                 if (!inode) {
1288                         ret = -ENOMEM;
1289                         goto out;
1290                 }
1291                 inode->i_fop = &sel_initcon_ops;
1292                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1293                 d_add(dentry, inode);
1294         }
1295 out:
1296         return ret;
1297 }
1298
1299 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1300 {
1301         return a / b - (a % b < 0);
1302 }
1303
1304 static inline unsigned long sel_class_to_ino(u16 class)
1305 {
1306         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1307 }
1308
1309 static inline u16 sel_ino_to_class(unsigned long ino)
1310 {
1311         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1312 }
1313
1314 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1315 {
1316         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1317 }
1318
1319 static inline u32 sel_ino_to_perm(unsigned long ino)
1320 {
1321         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1322 }
1323
1324 static ssize_t sel_read_class(struct file *file, char __user *buf,
1325                                 size_t count, loff_t *ppos)
1326 {
1327         ssize_t rc, len;
1328         char *page;
1329         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1330
1331         page = (char *)__get_free_page(GFP_KERNEL);
1332         if (!page) {
1333                 rc = -ENOMEM;
1334                 goto out;
1335         }
1336
1337         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1338         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1339         free_page((unsigned long)page);
1340 out:
1341         return rc;
1342 }
1343
1344 static const struct file_operations sel_class_ops = {
1345         .read           = sel_read_class,
1346         .llseek         = generic_file_llseek,
1347 };
1348
1349 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1350                                 size_t count, loff_t *ppos)
1351 {
1352         ssize_t rc, len;
1353         char *page;
1354         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1355
1356         page = (char *)__get_free_page(GFP_KERNEL);
1357         if (!page) {
1358                 rc = -ENOMEM;
1359                 goto out;
1360         }
1361
1362         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1363         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1364         free_page((unsigned long)page);
1365 out:
1366         return rc;
1367 }
1368
1369 static const struct file_operations sel_perm_ops = {
1370         .read           = sel_read_perm,
1371         .llseek         = generic_file_llseek,
1372 };
1373
1374 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1375                                   size_t count, loff_t *ppos)
1376 {
1377         int value;
1378         char tmpbuf[TMPBUFLEN];
1379         ssize_t length;
1380         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1381
1382         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1383         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1384
1385         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1386 }
1387
1388 static const struct file_operations sel_policycap_ops = {
1389         .read           = sel_read_policycap,
1390         .llseek         = generic_file_llseek,
1391 };
1392
1393 static int sel_make_perm_files(char *objclass, int classvalue,
1394                                 struct dentry *dir)
1395 {
1396         int i, rc = 0, nperms;
1397         char **perms;
1398
1399         rc = security_get_permissions(objclass, &perms, &nperms);
1400         if (rc)
1401                 goto out;
1402
1403         for (i = 0; i < nperms; i++) {
1404                 struct inode *inode;
1405                 struct dentry *dentry;
1406
1407                 dentry = d_alloc_name(dir, perms[i]);
1408                 if (!dentry) {
1409                         rc = -ENOMEM;
1410                         goto out1;
1411                 }
1412
1413                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1414                 if (!inode) {
1415                         rc = -ENOMEM;
1416                         goto out1;
1417                 }
1418                 inode->i_fop = &sel_perm_ops;
1419                 /* i+1 since perm values are 1-indexed */
1420                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1421                 d_add(dentry, inode);
1422         }
1423
1424 out1:
1425         for (i = 0; i < nperms; i++)
1426                 kfree(perms[i]);
1427         kfree(perms);
1428 out:
1429         return rc;
1430 }
1431
1432 static int sel_make_class_dir_entries(char *classname, int index,
1433                                         struct dentry *dir)
1434 {
1435         struct dentry *dentry = NULL;
1436         struct inode *inode = NULL;
1437         int rc;
1438
1439         dentry = d_alloc_name(dir, "index");
1440         if (!dentry) {
1441                 rc = -ENOMEM;
1442                 goto out;
1443         }
1444
1445         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1446         if (!inode) {
1447                 rc = -ENOMEM;
1448                 goto out;
1449         }
1450
1451         inode->i_fop = &sel_class_ops;
1452         inode->i_ino = sel_class_to_ino(index);
1453         d_add(dentry, inode);
1454
1455         dentry = d_alloc_name(dir, "perms");
1456         if (!dentry) {
1457                 rc = -ENOMEM;
1458                 goto out;
1459         }
1460
1461         rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1462         if (rc)
1463                 goto out;
1464
1465         rc = sel_make_perm_files(classname, index, dentry);
1466
1467 out:
1468         return rc;
1469 }
1470
1471 static void sel_remove_classes(void)
1472 {
1473         struct list_head *class_node;
1474
1475         list_for_each(class_node, &class_dir->d_subdirs) {
1476                 struct dentry *class_subdir = list_entry(class_node,
1477                                         struct dentry, d_u.d_child);
1478                 struct list_head *class_subdir_node;
1479
1480                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1481                         struct dentry *d = list_entry(class_subdir_node,
1482                                                 struct dentry, d_u.d_child);
1483
1484                         if (d->d_inode)
1485                                 if (d->d_inode->i_mode & S_IFDIR)
1486                                         sel_remove_entries(d);
1487                 }
1488
1489                 sel_remove_entries(class_subdir);
1490         }
1491
1492         sel_remove_entries(class_dir);
1493 }
1494
1495 static int sel_make_classes(void)
1496 {
1497         int rc = 0, nclasses, i;
1498         char **classes;
1499
1500         /* delete any existing entries */
1501         sel_remove_classes();
1502
1503         rc = security_get_classes(&classes, &nclasses);
1504         if (rc < 0)
1505                 goto out;
1506
1507         /* +2 since classes are 1-indexed */
1508         last_class_ino = sel_class_to_ino(nclasses + 2);
1509
1510         for (i = 0; i < nclasses; i++) {
1511                 struct dentry *class_name_dir;
1512
1513                 class_name_dir = d_alloc_name(class_dir, classes[i]);
1514                 if (!class_name_dir) {
1515                         rc = -ENOMEM;
1516                         goto out1;
1517                 }
1518
1519                 rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1520                                 &last_class_ino);
1521                 if (rc)
1522                         goto out1;
1523
1524                 /* i+1 since class values are 1-indexed */
1525                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1526                                 class_name_dir);
1527                 if (rc)
1528                         goto out1;
1529         }
1530
1531 out1:
1532         for (i = 0; i < nclasses; i++)
1533                 kfree(classes[i]);
1534         kfree(classes);
1535 out:
1536         return rc;
1537 }
1538
1539 static int sel_make_policycap(void)
1540 {
1541         unsigned int iter;
1542         struct dentry *dentry = NULL;
1543         struct inode *inode = NULL;
1544
1545         sel_remove_entries(policycap_dir);
1546
1547         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1548                 if (iter < ARRAY_SIZE(policycap_names))
1549                         dentry = d_alloc_name(policycap_dir,
1550                                               policycap_names[iter]);
1551                 else
1552                         dentry = d_alloc_name(policycap_dir, "unknown");
1553
1554                 if (dentry == NULL)
1555                         return -ENOMEM;
1556
1557                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1558                 if (inode == NULL)
1559                         return -ENOMEM;
1560
1561                 inode->i_fop = &sel_policycap_ops;
1562                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1563                 d_add(dentry, inode);
1564         }
1565
1566         return 0;
1567 }
1568
1569 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1570                         unsigned long *ino)
1571 {
1572         int ret = 0;
1573         struct inode *inode;
1574
1575         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1576         if (!inode) {
1577                 ret = -ENOMEM;
1578                 goto out;
1579         }
1580         inode->i_op = &simple_dir_inode_operations;
1581         inode->i_fop = &simple_dir_operations;
1582         inode->i_ino = ++(*ino);
1583         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1584         inc_nlink(inode);
1585         d_add(dentry, inode);
1586         /* bump link count on parent directory, too */
1587         inc_nlink(dir);
1588 out:
1589         return ret;
1590 }
1591
1592 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1593 {
1594         int ret;
1595         struct dentry *dentry;
1596         struct inode *inode, *root_inode;
1597         struct inode_security_struct *isec;
1598
1599         static struct tree_descr selinux_files[] = {
1600                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1601                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1602                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1603                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1604                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1605                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1606                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1607                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1608                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1609                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1610                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1611                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1612                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1613                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1614                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1615                 /* last one */ {""}
1616         };
1617         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1618         if (ret)
1619                 goto err;
1620
1621         root_inode = sb->s_root->d_inode;
1622
1623         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1624         if (!dentry) {
1625                 ret = -ENOMEM;
1626                 goto err;
1627         }
1628
1629         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1630         if (ret)
1631                 goto err;
1632
1633         bool_dir = dentry;
1634
1635         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1636         if (!dentry) {
1637                 ret = -ENOMEM;
1638                 goto err;
1639         }
1640
1641         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1642         if (!inode) {
1643                 ret = -ENOMEM;
1644                 goto err;
1645         }
1646         inode->i_ino = ++sel_last_ino;
1647         isec = (struct inode_security_struct *)inode->i_security;
1648         isec->sid = SECINITSID_DEVNULL;
1649         isec->sclass = SECCLASS_CHR_FILE;
1650         isec->initialized = 1;
1651
1652         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1653         d_add(dentry, inode);
1654         selinux_null = dentry;
1655
1656         dentry = d_alloc_name(sb->s_root, "avc");
1657         if (!dentry) {
1658                 ret = -ENOMEM;
1659                 goto err;
1660         }
1661
1662         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1663         if (ret)
1664                 goto err;
1665
1666         ret = sel_make_avc_files(dentry);
1667         if (ret)
1668                 goto err;
1669
1670         dentry = d_alloc_name(sb->s_root, "initial_contexts");
1671         if (!dentry) {
1672                 ret = -ENOMEM;
1673                 goto err;
1674         }
1675
1676         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1677         if (ret)
1678                 goto err;
1679
1680         ret = sel_make_initcon_files(dentry);
1681         if (ret)
1682                 goto err;
1683
1684         dentry = d_alloc_name(sb->s_root, "class");
1685         if (!dentry) {
1686                 ret = -ENOMEM;
1687                 goto err;
1688         }
1689
1690         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1691         if (ret)
1692                 goto err;
1693
1694         class_dir = dentry;
1695
1696         dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1697         if (!dentry) {
1698                 ret = -ENOMEM;
1699                 goto err;
1700         }
1701
1702         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1703         if (ret)
1704                 goto err;
1705
1706         policycap_dir = dentry;
1707
1708 out:
1709         return ret;
1710 err:
1711         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1712                 __func__);
1713         goto out;
1714 }
1715
1716 static int sel_get_sb(struct file_system_type *fs_type,
1717                       int flags, const char *dev_name, void *data,
1718                       struct vfsmount *mnt)
1719 {
1720         return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
1721 }
1722
1723 static struct file_system_type sel_fs_type = {
1724         .name           = "selinuxfs",
1725         .get_sb         = sel_get_sb,
1726         .kill_sb        = kill_litter_super,
1727 };
1728
1729 struct vfsmount *selinuxfs_mount;
1730
1731 static int __init init_sel_fs(void)
1732 {
1733         int err;
1734
1735         if (!selinux_enabled)
1736                 return 0;
1737         err = register_filesystem(&sel_fs_type);
1738         if (!err) {
1739                 selinuxfs_mount = kern_mount(&sel_fs_type);
1740                 if (IS_ERR(selinuxfs_mount)) {
1741                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1742                         err = PTR_ERR(selinuxfs_mount);
1743                         selinuxfs_mount = NULL;
1744                 }
1745         }
1746         return err;
1747 }
1748
1749 __initcall(init_sel_fs);
1750
1751 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1752 void exit_sel_fs(void)
1753 {
1754         unregister_filesystem(&sel_fs_type);
1755 }
1756 #endif