Merge branch 'audit.b3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit...
[linux-2.6.git] / security / selinux / selinuxfs.c
1 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
2  *
3  *      Added conditional policy language extensions
4  *
5  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
6  * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
7  *      This program is free software; you can redistribute it and/or modify
8  *      it under the terms of the GNU General Public License as published by
9  *      the Free Software Foundation, version 2.
10  */
11
12 #include <linux/config.h>
13 #include <linux/kernel.h>
14 #include <linux/pagemap.h>
15 #include <linux/slab.h>
16 #include <linux/vmalloc.h>
17 #include <linux/fs.h>
18 #include <linux/mutex.h>
19 #include <linux/init.h>
20 #include <linux/string.h>
21 #include <linux/security.h>
22 #include <linux/major.h>
23 #include <linux/seq_file.h>
24 #include <linux/percpu.h>
25 #include <linux/audit.h>
26 #include <asm/uaccess.h>
27 #include <asm/semaphore.h>
28
29 /* selinuxfs pseudo filesystem for exporting the security policy API.
30    Based on the proc code and the fs/nfsd/nfsctl.c code. */
31
32 #include "flask.h"
33 #include "avc.h"
34 #include "avc_ss.h"
35 #include "security.h"
36 #include "objsec.h"
37 #include "conditional.h"
38
39 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
40
41 static int __init checkreqprot_setup(char *str)
42 {
43         selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0;
44         return 1;
45 }
46 __setup("checkreqprot=", checkreqprot_setup);
47
48
49 static DEFINE_MUTEX(sel_mutex);
50
51 /* global data for booleans */
52 static struct dentry *bool_dir = NULL;
53 static int bool_num = 0;
54 static int *bool_pending_values = NULL;
55
56 extern void selnl_notify_setenforce(int val);
57
58 /* Check whether a task is allowed to use a security operation. */
59 static int task_has_security(struct task_struct *tsk,
60                              u32 perms)
61 {
62         struct task_security_struct *tsec;
63
64         tsec = tsk->security;
65         if (!tsec)
66                 return -EACCES;
67
68         return avc_has_perm(tsec->sid, SECINITSID_SECURITY,
69                             SECCLASS_SECURITY, perms, NULL);
70 }
71
72 enum sel_inos {
73         SEL_ROOT_INO = 2,
74         SEL_LOAD,       /* load policy */
75         SEL_ENFORCE,    /* get or set enforcing status */
76         SEL_CONTEXT,    /* validate context */
77         SEL_ACCESS,     /* compute access decision */
78         SEL_CREATE,     /* compute create labeling decision */
79         SEL_RELABEL,    /* compute relabeling decision */
80         SEL_USER,       /* compute reachable user contexts */
81         SEL_POLICYVERS, /* return policy version for this kernel */
82         SEL_COMMIT_BOOLS, /* commit new boolean values */
83         SEL_MLS,        /* return if MLS policy is enabled */
84         SEL_DISABLE,    /* disable SELinux until next reboot */
85         SEL_AVC,        /* AVC management directory */
86         SEL_MEMBER,     /* compute polyinstantiation membership decision */
87         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
88 };
89
90 #define TMPBUFLEN       12
91 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
92                                 size_t count, loff_t *ppos)
93 {
94         char tmpbuf[TMPBUFLEN];
95         ssize_t length;
96
97         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
98         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
99 }
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 static ssize_t sel_write_enforce(struct file * file, const char __user * buf,
103                                  size_t count, loff_t *ppos)
104
105 {
106         char *page;
107         ssize_t length;
108         int new_value;
109
110         if (count >= PAGE_SIZE)
111                 return -ENOMEM;
112         if (*ppos != 0) {
113                 /* No partial writes. */
114                 return -EINVAL;
115         }
116         page = (char*)get_zeroed_page(GFP_KERNEL);
117         if (!page)
118                 return -ENOMEM;
119         length = -EFAULT;
120         if (copy_from_user(page, buf, count))
121                 goto out;
122
123         length = -EINVAL;
124         if (sscanf(page, "%d", &new_value) != 1)
125                 goto out;
126
127         if (new_value != selinux_enforcing) {
128                 length = task_has_security(current, SECURITY__SETENFORCE);
129                 if (length)
130                         goto out;
131                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
132                         "enforcing=%d old_enforcing=%d auid=%u", new_value, 
133                         selinux_enforcing,
134                         audit_get_loginuid(current->audit_context));
135                 selinux_enforcing = new_value;
136                 if (selinux_enforcing)
137                         avc_ss_reset(0);
138                 selnl_notify_setenforce(selinux_enforcing);
139         }
140         length = count;
141 out:
142         free_page((unsigned long) page);
143         return length;
144 }
145 #else
146 #define sel_write_enforce NULL
147 #endif
148
149 static struct file_operations sel_enforce_ops = {
150         .read           = sel_read_enforce,
151         .write          = sel_write_enforce,
152 };
153
154 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
155 static ssize_t sel_write_disable(struct file * file, const char __user * buf,
156                                  size_t count, loff_t *ppos)
157
158 {
159         char *page;
160         ssize_t length;
161         int new_value;
162         extern int selinux_disable(void);
163
164         if (count >= PAGE_SIZE)
165                 return -ENOMEM;
166         if (*ppos != 0) {
167                 /* No partial writes. */
168                 return -EINVAL;
169         }
170         page = (char*)get_zeroed_page(GFP_KERNEL);
171         if (!page)
172                 return -ENOMEM;
173         length = -EFAULT;
174         if (copy_from_user(page, buf, count))
175                 goto out;
176
177         length = -EINVAL;
178         if (sscanf(page, "%d", &new_value) != 1)
179                 goto out;
180
181         if (new_value) {
182                 length = selinux_disable();
183                 if (length < 0)
184                         goto out;
185                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
186                         "selinux=0 auid=%u",
187                         audit_get_loginuid(current->audit_context));
188         }
189
190         length = count;
191 out:
192         free_page((unsigned long) page);
193         return length;
194 }
195 #else
196 #define sel_write_disable NULL
197 #endif
198
199 static struct file_operations sel_disable_ops = {
200         .write          = sel_write_disable,
201 };
202
203 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
204                                    size_t count, loff_t *ppos)
205 {
206         char tmpbuf[TMPBUFLEN];
207         ssize_t length;
208
209         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
210         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
211 }
212
213 static struct file_operations sel_policyvers_ops = {
214         .read           = sel_read_policyvers,
215 };
216
217 /* declaration for sel_write_load */
218 static int sel_make_bools(void);
219
220 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
221                                 size_t count, loff_t *ppos)
222 {
223         char tmpbuf[TMPBUFLEN];
224         ssize_t length;
225
226         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
227         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
228 }
229
230 static struct file_operations sel_mls_ops = {
231         .read           = sel_read_mls,
232 };
233
234 static ssize_t sel_write_load(struct file * file, const char __user * buf,
235                               size_t count, loff_t *ppos)
236
237 {
238         int ret;
239         ssize_t length;
240         void *data = NULL;
241
242         mutex_lock(&sel_mutex);
243
244         length = task_has_security(current, SECURITY__LOAD_POLICY);
245         if (length)
246                 goto out;
247
248         if (*ppos != 0) {
249                 /* No partial writes. */
250                 length = -EINVAL;
251                 goto out;
252         }
253
254         if ((count > 64 * 1024 * 1024)
255             || (data = vmalloc(count)) == NULL) {
256                 length = -ENOMEM;
257                 goto out;
258         }
259
260         length = -EFAULT;
261         if (copy_from_user(data, buf, count) != 0)
262                 goto out;
263
264         length = security_load_policy(data, count);
265         if (length)
266                 goto out;
267
268         ret = sel_make_bools();
269         if (ret)
270                 length = ret;
271         else
272                 length = count;
273         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
274                 "policy loaded auid=%u",
275                 audit_get_loginuid(current->audit_context));
276 out:
277         mutex_unlock(&sel_mutex);
278         vfree(data);
279         return length;
280 }
281
282 static struct file_operations sel_load_ops = {
283         .write          = sel_write_load,
284 };
285
286 static ssize_t sel_write_context(struct file * file, char *buf, size_t size)
287 {
288         char *canon;
289         u32 sid, len;
290         ssize_t length;
291
292         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
293         if (length)
294                 return length;
295
296         length = security_context_to_sid(buf, size, &sid);
297         if (length < 0)
298                 return length;
299
300         length = security_sid_to_context(sid, &canon, &len);
301         if (length < 0)
302                 return length;
303
304         if (len > SIMPLE_TRANSACTION_LIMIT) {
305                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
306                        "max\n", __FUNCTION__, len);
307                 length = -ERANGE;
308                 goto out;
309         }
310
311         memcpy(buf, canon, len);
312         length = len;
313 out:
314         kfree(canon);
315         return length;
316 }
317
318 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
319                                      size_t count, loff_t *ppos)
320 {
321         char tmpbuf[TMPBUFLEN];
322         ssize_t length;
323
324         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
325         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
326 }
327
328 static ssize_t sel_write_checkreqprot(struct file * file, const char __user * buf,
329                                       size_t count, loff_t *ppos)
330 {
331         char *page;
332         ssize_t length;
333         unsigned int new_value;
334
335         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
336         if (length)
337                 return length;
338
339         if (count >= PAGE_SIZE)
340                 return -ENOMEM;
341         if (*ppos != 0) {
342                 /* No partial writes. */
343                 return -EINVAL;
344         }
345         page = (char*)get_zeroed_page(GFP_KERNEL);
346         if (!page)
347                 return -ENOMEM;
348         length = -EFAULT;
349         if (copy_from_user(page, buf, count))
350                 goto out;
351
352         length = -EINVAL;
353         if (sscanf(page, "%u", &new_value) != 1)
354                 goto out;
355
356         selinux_checkreqprot = new_value ? 1 : 0;
357         length = count;
358 out:
359         free_page((unsigned long) page);
360         return length;
361 }
362 static struct file_operations sel_checkreqprot_ops = {
363         .read           = sel_read_checkreqprot,
364         .write          = sel_write_checkreqprot,
365 };
366
367 /*
368  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
369  */
370 static ssize_t sel_write_access(struct file * file, char *buf, size_t size);
371 static ssize_t sel_write_create(struct file * file, char *buf, size_t size);
372 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size);
373 static ssize_t sel_write_user(struct file * file, char *buf, size_t size);
374 static ssize_t sel_write_member(struct file * file, char *buf, size_t size);
375
376 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
377         [SEL_ACCESS] = sel_write_access,
378         [SEL_CREATE] = sel_write_create,
379         [SEL_RELABEL] = sel_write_relabel,
380         [SEL_USER] = sel_write_user,
381         [SEL_MEMBER] = sel_write_member,
382         [SEL_CONTEXT] = sel_write_context,
383 };
384
385 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
386 {
387         ino_t ino =  file->f_dentry->d_inode->i_ino;
388         char *data;
389         ssize_t rv;
390
391         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
392                 return -EINVAL;
393
394         data = simple_transaction_get(file, buf, size);
395         if (IS_ERR(data))
396                 return PTR_ERR(data);
397
398         rv =  write_op[ino](file, data, size);
399         if (rv>0) {
400                 simple_transaction_set(file, rv);
401                 rv = size;
402         }
403         return rv;
404 }
405
406 static struct file_operations transaction_ops = {
407         .write          = selinux_transaction_write,
408         .read           = simple_transaction_read,
409         .release        = simple_transaction_release,
410 };
411
412 /*
413  * payload - write methods
414  * If the method has a response, the response should be put in buf,
415  * and the length returned.  Otherwise return 0 or and -error.
416  */
417
418 static ssize_t sel_write_access(struct file * file, char *buf, size_t size)
419 {
420         char *scon, *tcon;
421         u32 ssid, tsid;
422         u16 tclass;
423         u32 req;
424         struct av_decision avd;
425         ssize_t length;
426
427         length = task_has_security(current, SECURITY__COMPUTE_AV);
428         if (length)
429                 return length;
430
431         length = -ENOMEM;
432         scon = kzalloc(size+1, GFP_KERNEL);
433         if (!scon)
434                 return length;
435
436         tcon = kzalloc(size+1, GFP_KERNEL);
437         if (!tcon)
438                 goto out;
439
440         length = -EINVAL;
441         if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
442                 goto out2;
443
444         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
445         if (length < 0)
446                 goto out2;
447         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
448         if (length < 0)
449                 goto out2;
450
451         length = security_compute_av(ssid, tsid, tclass, req, &avd);
452         if (length < 0)
453                 goto out2;
454
455         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
456                           "%x %x %x %x %u",
457                           avd.allowed, avd.decided,
458                           avd.auditallow, avd.auditdeny,
459                           avd.seqno);
460 out2:
461         kfree(tcon);
462 out:
463         kfree(scon);
464         return length;
465 }
466
467 static ssize_t sel_write_create(struct file * file, char *buf, size_t size)
468 {
469         char *scon, *tcon;
470         u32 ssid, tsid, newsid;
471         u16 tclass;
472         ssize_t length;
473         char *newcon;
474         u32 len;
475
476         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
477         if (length)
478                 return length;
479
480         length = -ENOMEM;
481         scon = kzalloc(size+1, GFP_KERNEL);
482         if (!scon)
483                 return length;
484
485         tcon = kzalloc(size+1, GFP_KERNEL);
486         if (!tcon)
487                 goto out;
488
489         length = -EINVAL;
490         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
491                 goto out2;
492
493         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
494         if (length < 0)
495                 goto out2;
496         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
497         if (length < 0)
498                 goto out2;
499
500         length = security_transition_sid(ssid, tsid, tclass, &newsid);
501         if (length < 0)
502                 goto out2;
503
504         length = security_sid_to_context(newsid, &newcon, &len);
505         if (length < 0)
506                 goto out2;
507
508         if (len > SIMPLE_TRANSACTION_LIMIT) {
509                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
510                        "max\n", __FUNCTION__, len);
511                 length = -ERANGE;
512                 goto out3;
513         }
514
515         memcpy(buf, newcon, len);
516         length = len;
517 out3:
518         kfree(newcon);
519 out2:
520         kfree(tcon);
521 out:
522         kfree(scon);
523         return length;
524 }
525
526 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size)
527 {
528         char *scon, *tcon;
529         u32 ssid, tsid, newsid;
530         u16 tclass;
531         ssize_t length;
532         char *newcon;
533         u32 len;
534
535         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
536         if (length)
537                 return length;
538
539         length = -ENOMEM;
540         scon = kzalloc(size+1, GFP_KERNEL);
541         if (!scon)
542                 return length;
543
544         tcon = kzalloc(size+1, GFP_KERNEL);
545         if (!tcon)
546                 goto out;
547
548         length = -EINVAL;
549         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
550                 goto out2;
551
552         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
553         if (length < 0)
554                 goto out2;
555         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
556         if (length < 0)
557                 goto out2;
558
559         length = security_change_sid(ssid, tsid, tclass, &newsid);
560         if (length < 0)
561                 goto out2;
562
563         length = security_sid_to_context(newsid, &newcon, &len);
564         if (length < 0)
565                 goto out2;
566
567         if (len > SIMPLE_TRANSACTION_LIMIT) {
568                 length = -ERANGE;
569                 goto out3;
570         }
571
572         memcpy(buf, newcon, len);
573         length = len;
574 out3:
575         kfree(newcon);
576 out2:
577         kfree(tcon);
578 out:
579         kfree(scon);
580         return length;
581 }
582
583 static ssize_t sel_write_user(struct file * file, char *buf, size_t size)
584 {
585         char *con, *user, *ptr;
586         u32 sid, *sids;
587         ssize_t length;
588         char *newcon;
589         int i, rc;
590         u32 len, nsids;
591
592         length = task_has_security(current, SECURITY__COMPUTE_USER);
593         if (length)
594                 return length;
595
596         length = -ENOMEM;
597         con = kzalloc(size+1, GFP_KERNEL);
598         if (!con)
599                 return length;
600
601         user = kzalloc(size+1, GFP_KERNEL);
602         if (!user)
603                 goto out;
604
605         length = -EINVAL;
606         if (sscanf(buf, "%s %s", con, user) != 2)
607                 goto out2;
608
609         length = security_context_to_sid(con, strlen(con)+1, &sid);
610         if (length < 0)
611                 goto out2;
612
613         length = security_get_user_sids(sid, user, &sids, &nsids);
614         if (length < 0)
615                 goto out2;
616
617         length = sprintf(buf, "%u", nsids) + 1;
618         ptr = buf + length;
619         for (i = 0; i < nsids; i++) {
620                 rc = security_sid_to_context(sids[i], &newcon, &len);
621                 if (rc) {
622                         length = rc;
623                         goto out3;
624                 }
625                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
626                         kfree(newcon);
627                         length = -ERANGE;
628                         goto out3;
629                 }
630                 memcpy(ptr, newcon, len);
631                 kfree(newcon);
632                 ptr += len;
633                 length += len;
634         }
635 out3:
636         kfree(sids);
637 out2:
638         kfree(user);
639 out:
640         kfree(con);
641         return length;
642 }
643
644 static ssize_t sel_write_member(struct file * file, char *buf, size_t size)
645 {
646         char *scon, *tcon;
647         u32 ssid, tsid, newsid;
648         u16 tclass;
649         ssize_t length;
650         char *newcon;
651         u32 len;
652
653         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
654         if (length)
655                 return length;
656
657         length = -ENOMEM;
658         scon = kzalloc(size+1, GFP_KERNEL);
659         if (!scon)
660                 return length;
661
662         tcon = kzalloc(size+1, GFP_KERNEL);
663         if (!tcon)
664                 goto out;
665
666         length = -EINVAL;
667         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
668                 goto out2;
669
670         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
671         if (length < 0)
672                 goto out2;
673         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
674         if (length < 0)
675                 goto out2;
676
677         length = security_member_sid(ssid, tsid, tclass, &newsid);
678         if (length < 0)
679                 goto out2;
680
681         length = security_sid_to_context(newsid, &newcon, &len);
682         if (length < 0)
683                 goto out2;
684
685         if (len > SIMPLE_TRANSACTION_LIMIT) {
686                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
687                        "max\n", __FUNCTION__, len);
688                 length = -ERANGE;
689                 goto out3;
690         }
691
692         memcpy(buf, newcon, len);
693         length = len;
694 out3:
695         kfree(newcon);
696 out2:
697         kfree(tcon);
698 out:
699         kfree(scon);
700         return length;
701 }
702
703 static struct inode *sel_make_inode(struct super_block *sb, int mode)
704 {
705         struct inode *ret = new_inode(sb);
706
707         if (ret) {
708                 ret->i_mode = mode;
709                 ret->i_uid = ret->i_gid = 0;
710                 ret->i_blksize = PAGE_CACHE_SIZE;
711                 ret->i_blocks = 0;
712                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
713         }
714         return ret;
715 }
716
717 #define BOOL_INO_OFFSET 30
718
719 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
720                              size_t count, loff_t *ppos)
721 {
722         char *page = NULL;
723         ssize_t length;
724         ssize_t ret;
725         int cur_enforcing;
726         struct inode *inode;
727
728         mutex_lock(&sel_mutex);
729
730         ret = -EFAULT;
731
732         /* check to see if this file has been deleted */
733         if (!filep->f_op)
734                 goto out;
735
736         if (count > PAGE_SIZE) {
737                 ret = -EINVAL;
738                 goto out;
739         }
740         if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) {
741                 ret = -ENOMEM;
742                 goto out;
743         }
744
745         inode = filep->f_dentry->d_inode;
746         cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET);
747         if (cur_enforcing < 0) {
748                 ret = cur_enforcing;
749                 goto out;
750         }
751
752         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
753                           bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]);
754         ret = simple_read_from_buffer(buf, count, ppos, page, length);
755 out:
756         mutex_unlock(&sel_mutex);
757         if (page)
758                 free_page((unsigned long)page);
759         return ret;
760 }
761
762 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
763                               size_t count, loff_t *ppos)
764 {
765         char *page = NULL;
766         ssize_t length = -EFAULT;
767         int new_value;
768         struct inode *inode;
769
770         mutex_lock(&sel_mutex);
771
772         length = task_has_security(current, SECURITY__SETBOOL);
773         if (length)
774                 goto out;
775
776         /* check to see if this file has been deleted */
777         if (!filep->f_op)
778                 goto out;
779
780         if (count >= PAGE_SIZE) {
781                 length = -ENOMEM;
782                 goto out;
783         }
784         if (*ppos != 0) {
785                 /* No partial writes. */
786                 goto out;
787         }
788         page = (char*)get_zeroed_page(GFP_KERNEL);
789         if (!page) {
790                 length = -ENOMEM;
791                 goto out;
792         }
793
794         if (copy_from_user(page, buf, count))
795                 goto out;
796
797         length = -EINVAL;
798         if (sscanf(page, "%d", &new_value) != 1)
799                 goto out;
800
801         if (new_value)
802                 new_value = 1;
803
804         inode = filep->f_dentry->d_inode;
805         bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = new_value;
806         length = count;
807
808 out:
809         mutex_unlock(&sel_mutex);
810         if (page)
811                 free_page((unsigned long) page);
812         return length;
813 }
814
815 static struct file_operations sel_bool_ops = {
816         .read           = sel_read_bool,
817         .write          = sel_write_bool,
818 };
819
820 static ssize_t sel_commit_bools_write(struct file *filep,
821                                       const char __user *buf,
822                                       size_t count, loff_t *ppos)
823 {
824         char *page = NULL;
825         ssize_t length = -EFAULT;
826         int new_value;
827
828         mutex_lock(&sel_mutex);
829
830         length = task_has_security(current, SECURITY__SETBOOL);
831         if (length)
832                 goto out;
833
834         /* check to see if this file has been deleted */
835         if (!filep->f_op)
836                 goto out;
837
838         if (count >= PAGE_SIZE) {
839                 length = -ENOMEM;
840                 goto out;
841         }
842         if (*ppos != 0) {
843                 /* No partial writes. */
844                 goto out;
845         }
846         page = (char*)get_zeroed_page(GFP_KERNEL);
847         if (!page) {
848                 length = -ENOMEM;
849                 goto out;
850         }
851
852         if (copy_from_user(page, buf, count))
853                 goto out;
854
855         length = -EINVAL;
856         if (sscanf(page, "%d", &new_value) != 1)
857                 goto out;
858
859         if (new_value && bool_pending_values) {
860                 security_set_bools(bool_num, bool_pending_values);
861         }
862
863         length = count;
864
865 out:
866         mutex_unlock(&sel_mutex);
867         if (page)
868                 free_page((unsigned long) page);
869         return length;
870 }
871
872 static struct file_operations sel_commit_bools_ops = {
873         .write          = sel_commit_bools_write,
874 };
875
876 /* delete booleans - partial revoke() from
877  * fs/proc/generic.c proc_kill_inodes */
878 static void sel_remove_bools(struct dentry *de)
879 {
880         struct list_head *p, *node;
881         struct super_block *sb = de->d_sb;
882
883         spin_lock(&dcache_lock);
884         node = de->d_subdirs.next;
885         while (node != &de->d_subdirs) {
886                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
887                 list_del_init(node);
888
889                 if (d->d_inode) {
890                         d = dget_locked(d);
891                         spin_unlock(&dcache_lock);
892                         d_delete(d);
893                         simple_unlink(de->d_inode, d);
894                         dput(d);
895                         spin_lock(&dcache_lock);
896                 }
897                 node = de->d_subdirs.next;
898         }
899
900         spin_unlock(&dcache_lock);
901
902         file_list_lock();
903         list_for_each(p, &sb->s_files) {
904                 struct file * filp = list_entry(p, struct file, f_u.fu_list);
905                 struct dentry * dentry = filp->f_dentry;
906
907                 if (dentry->d_parent != de) {
908                         continue;
909                 }
910                 filp->f_op = NULL;
911         }
912         file_list_unlock();
913 }
914
915 #define BOOL_DIR_NAME "booleans"
916
917 static int sel_make_bools(void)
918 {
919         int i, ret = 0;
920         ssize_t len;
921         struct dentry *dentry = NULL;
922         struct dentry *dir = bool_dir;
923         struct inode *inode = NULL;
924         struct inode_security_struct *isec;
925         char **names = NULL, *page;
926         int num;
927         int *values = NULL;
928         u32 sid;
929
930         /* remove any existing files */
931         kfree(bool_pending_values);
932         bool_pending_values = NULL;
933
934         sel_remove_bools(dir);
935
936         if (!(page = (char*)get_zeroed_page(GFP_KERNEL)))
937                 return -ENOMEM;
938
939         ret = security_get_bools(&num, &names, &values);
940         if (ret != 0)
941                 goto out;
942
943         for (i = 0; i < num; i++) {
944                 dentry = d_alloc_name(dir, names[i]);
945                 if (!dentry) {
946                         ret = -ENOMEM;
947                         goto err;
948                 }
949                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
950                 if (!inode) {
951                         ret = -ENOMEM;
952                         goto err;
953                 }
954
955                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
956                 if (len < 0) {
957                         ret = -EINVAL;
958                         goto err;
959                 } else if (len >= PAGE_SIZE) {
960                         ret = -ENAMETOOLONG;
961                         goto err;
962                 }
963                 isec = (struct inode_security_struct*)inode->i_security;
964                 if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid)))
965                         goto err;
966                 isec->sid = sid;
967                 isec->initialized = 1;
968                 inode->i_fop = &sel_bool_ops;
969                 inode->i_ino = i + BOOL_INO_OFFSET;
970                 d_add(dentry, inode);
971         }
972         bool_num = num;
973         bool_pending_values = values;
974 out:
975         free_page((unsigned long)page);
976         if (names) {
977                 for (i = 0; i < num; i++)
978                         kfree(names[i]);
979                 kfree(names);
980         }
981         return ret;
982 err:
983         kfree(values);
984         sel_remove_bools(dir);
985         ret = -ENOMEM;
986         goto out;
987 }
988
989 #define NULL_FILE_NAME "null"
990
991 struct dentry *selinux_null = NULL;
992
993 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
994                                             size_t count, loff_t *ppos)
995 {
996         char tmpbuf[TMPBUFLEN];
997         ssize_t length;
998
999         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1000         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1001 }
1002
1003 static ssize_t sel_write_avc_cache_threshold(struct file * file,
1004                                              const char __user * buf,
1005                                              size_t count, loff_t *ppos)
1006
1007 {
1008         char *page;
1009         ssize_t ret;
1010         int new_value;
1011
1012         if (count >= PAGE_SIZE) {
1013                 ret = -ENOMEM;
1014                 goto out;
1015         }
1016
1017         if (*ppos != 0) {
1018                 /* No partial writes. */
1019                 ret = -EINVAL;
1020                 goto out;
1021         }
1022
1023         page = (char*)get_zeroed_page(GFP_KERNEL);
1024         if (!page) {
1025                 ret = -ENOMEM;
1026                 goto out;
1027         }
1028
1029         if (copy_from_user(page, buf, count)) {
1030                 ret = -EFAULT;
1031                 goto out_free;
1032         }
1033
1034         if (sscanf(page, "%u", &new_value) != 1) {
1035                 ret = -EINVAL;
1036                 goto out;
1037         }
1038
1039         if (new_value != avc_cache_threshold) {
1040                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1041                 if (ret)
1042                         goto out_free;
1043                 avc_cache_threshold = new_value;
1044         }
1045         ret = count;
1046 out_free:
1047         free_page((unsigned long)page);
1048 out:
1049         return ret;
1050 }
1051
1052 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1053                                        size_t count, loff_t *ppos)
1054 {
1055         char *page;
1056         ssize_t ret = 0;
1057
1058         page = (char *)__get_free_page(GFP_KERNEL);
1059         if (!page) {
1060                 ret = -ENOMEM;
1061                 goto out;
1062         }
1063         ret = avc_get_hash_stats(page);
1064         if (ret >= 0)
1065                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1066         free_page((unsigned long)page);
1067 out:
1068         return ret;
1069 }
1070
1071 static struct file_operations sel_avc_cache_threshold_ops = {
1072         .read           = sel_read_avc_cache_threshold,
1073         .write          = sel_write_avc_cache_threshold,
1074 };
1075
1076 static struct file_operations sel_avc_hash_stats_ops = {
1077         .read           = sel_read_avc_hash_stats,
1078 };
1079
1080 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1081 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1082 {
1083         int cpu;
1084
1085         for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1086                 if (!cpu_possible(cpu))
1087                         continue;
1088                 *idx = cpu + 1;
1089                 return &per_cpu(avc_cache_stats, cpu);
1090         }
1091         return NULL;
1092 }
1093
1094 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1095 {
1096         loff_t n = *pos - 1;
1097
1098         if (*pos == 0)
1099                 return SEQ_START_TOKEN;
1100
1101         return sel_avc_get_stat_idx(&n);
1102 }
1103
1104 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1105 {
1106         return sel_avc_get_stat_idx(pos);
1107 }
1108
1109 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1110 {
1111         struct avc_cache_stats *st = v;
1112
1113         if (v == SEQ_START_TOKEN)
1114                 seq_printf(seq, "lookups hits misses allocations reclaims "
1115                            "frees\n");
1116         else
1117                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1118                            st->hits, st->misses, st->allocations,
1119                            st->reclaims, st->frees);
1120         return 0;
1121 }
1122
1123 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1124 { }
1125
1126 static struct seq_operations sel_avc_cache_stats_seq_ops = {
1127         .start          = sel_avc_stats_seq_start,
1128         .next           = sel_avc_stats_seq_next,
1129         .show           = sel_avc_stats_seq_show,
1130         .stop           = sel_avc_stats_seq_stop,
1131 };
1132
1133 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1134 {
1135         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1136 }
1137
1138 static struct file_operations sel_avc_cache_stats_ops = {
1139         .open           = sel_open_avc_cache_stats,
1140         .read           = seq_read,
1141         .llseek         = seq_lseek,
1142         .release        = seq_release,
1143 };
1144 #endif
1145
1146 static int sel_make_avc_files(struct dentry *dir)
1147 {
1148         int i, ret = 0;
1149         static struct tree_descr files[] = {
1150                 { "cache_threshold",
1151                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1152                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1153 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1154                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1155 #endif
1156         };
1157
1158         for (i = 0; i < ARRAY_SIZE(files); i++) {
1159                 struct inode *inode;
1160                 struct dentry *dentry;
1161
1162                 dentry = d_alloc_name(dir, files[i].name);
1163                 if (!dentry) {
1164                         ret = -ENOMEM;
1165                         goto out;
1166                 }
1167
1168                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1169                 if (!inode) {
1170                         ret = -ENOMEM;
1171                         goto out;
1172                 }
1173                 inode->i_fop = files[i].ops;
1174                 d_add(dentry, inode);
1175         }
1176 out:
1177         return ret;
1178 }
1179
1180 static int sel_make_dir(struct inode *dir, struct dentry *dentry)
1181 {
1182         int ret = 0;
1183         struct inode *inode;
1184
1185         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1186         if (!inode) {
1187                 ret = -ENOMEM;
1188                 goto out;
1189         }
1190         inode->i_op = &simple_dir_inode_operations;
1191         inode->i_fop = &simple_dir_operations;
1192         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1193         inode->i_nlink++;
1194         d_add(dentry, inode);
1195         /* bump link count on parent directory, too */
1196         dir->i_nlink++;
1197 out:
1198         return ret;
1199 }
1200
1201 static int sel_fill_super(struct super_block * sb, void * data, int silent)
1202 {
1203         int ret;
1204         struct dentry *dentry;
1205         struct inode *inode, *root_inode;
1206         struct inode_security_struct *isec;
1207
1208         static struct tree_descr selinux_files[] = {
1209                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1210                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1211                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1212                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1213                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1214                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1215                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1216                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1217                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1218                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1219                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1220                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1221                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1222                 /* last one */ {""}
1223         };
1224         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1225         if (ret)
1226                 goto err;
1227
1228         root_inode = sb->s_root->d_inode;
1229
1230         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1231         if (!dentry) {
1232                 ret = -ENOMEM;
1233                 goto err;
1234         }
1235
1236         ret = sel_make_dir(root_inode, dentry);
1237         if (ret)
1238                 goto err;
1239
1240         bool_dir = dentry;
1241
1242         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1243         if (!dentry) {
1244                 ret = -ENOMEM;
1245                 goto err;
1246         }
1247
1248         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1249         if (!inode) {
1250                 ret = -ENOMEM;
1251                 goto err;
1252         }
1253         isec = (struct inode_security_struct*)inode->i_security;
1254         isec->sid = SECINITSID_DEVNULL;
1255         isec->sclass = SECCLASS_CHR_FILE;
1256         isec->initialized = 1;
1257
1258         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1259         d_add(dentry, inode);
1260         selinux_null = dentry;
1261
1262         dentry = d_alloc_name(sb->s_root, "avc");
1263         if (!dentry) {
1264                 ret = -ENOMEM;
1265                 goto err;
1266         }
1267
1268         ret = sel_make_dir(root_inode, dentry);
1269         if (ret)
1270                 goto err;
1271
1272         ret = sel_make_avc_files(dentry);
1273         if (ret)
1274                 goto err;
1275 out:
1276         return ret;
1277 err:
1278         printk(KERN_ERR "%s:  failed while creating inodes\n", __FUNCTION__);
1279         goto out;
1280 }
1281
1282 static struct super_block *sel_get_sb(struct file_system_type *fs_type,
1283                                       int flags, const char *dev_name, void *data)
1284 {
1285         return get_sb_single(fs_type, flags, data, sel_fill_super);
1286 }
1287
1288 static struct file_system_type sel_fs_type = {
1289         .name           = "selinuxfs",
1290         .get_sb         = sel_get_sb,
1291         .kill_sb        = kill_litter_super,
1292 };
1293
1294 struct vfsmount *selinuxfs_mount;
1295
1296 static int __init init_sel_fs(void)
1297 {
1298         int err;
1299
1300         if (!selinux_enabled)
1301                 return 0;
1302         err = register_filesystem(&sel_fs_type);
1303         if (!err) {
1304                 selinuxfs_mount = kern_mount(&sel_fs_type);
1305                 if (IS_ERR(selinuxfs_mount)) {
1306                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1307                         err = PTR_ERR(selinuxfs_mount);
1308                         selinuxfs_mount = NULL;
1309                 }
1310         }
1311         return err;
1312 }
1313
1314 __initcall(init_sel_fs);
1315
1316 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1317 void exit_sel_fs(void)
1318 {
1319         unregister_filesystem(&sel_fs_type);
1320 }
1321 #endif