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[PATCH] reduce sizeof(struct file)
[linux-2.6/sactl.git] / security / selinux / selinuxfs.c
blobfdc3823897207284fafe407546b40cdc7edd7899
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/init.h>
19 #include <linux/string.h>
20 #include <linux/security.h>
21 #include <linux/major.h>
22 #include <linux/seq_file.h>
23 #include <linux/percpu.h>
24 #include <asm/uaccess.h>
25 #include <asm/semaphore.h>
26
27 /* selinuxfs pseudo filesystem for exporting the security policy API.
28 Based on the proc code and the fs/nfsd/nfsctl.c code. */
29
30 #include "flask.h"
31 #include "avc.h"
32 #include "avc_ss.h"
33 #include "security.h"
34 #include "objsec.h"
35 #include "conditional.h"
36
37 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
38
39 static int __init checkreqprot_setup(char *str)
40 {
41 selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0;
42 return 1;
43 }
44 __setup("checkreqprot=", checkreqprot_setup);
45
46
47 static DECLARE_MUTEX(sel_sem);
48
49 /* global data for booleans */
50 static struct dentry *bool_dir = NULL;
51 static int bool_num = 0;
52 static int *bool_pending_values = NULL;
53
54 extern void selnl_notify_setenforce(int val);
55
56 /* Check whether a task is allowed to use a security operation. */
57 static int task_has_security(struct task_struct *tsk,
58 u32 perms)
59 {
60 struct task_security_struct *tsec;
61
62 tsec = tsk->security;
63 if (!tsec)
64 return -EACCES;
65
66 return avc_has_perm(tsec->sid, SECINITSID_SECURITY,
67 SECCLASS_SECURITY, perms, NULL);
68 }
69
70 enum sel_inos {
71 SEL_ROOT_INO = 2,
72 SEL_LOAD, /* load policy */
73 SEL_ENFORCE, /* get or set enforcing status */
74 SEL_CONTEXT, /* validate context */
75 SEL_ACCESS, /* compute access decision */
76 SEL_CREATE, /* compute create labeling decision */
77 SEL_RELABEL, /* compute relabeling decision */
78 SEL_USER, /* compute reachable user contexts */
79 SEL_POLICYVERS, /* return policy version for this kernel */
80 SEL_COMMIT_BOOLS, /* commit new boolean values */
81 SEL_MLS, /* return if MLS policy is enabled */
82 SEL_DISABLE, /* disable SELinux until next reboot */
83 SEL_AVC, /* AVC management directory */
84 SEL_MEMBER, /* compute polyinstantiation membership decision */
85 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
86 };
87
88 #define TMPBUFLEN 12
89 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
90 size_t count, loff_t *ppos)
91 {
92 char tmpbuf[TMPBUFLEN];
93 ssize_t length;
94
95 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
96 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
97 }
98
99 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
100 static ssize_t sel_write_enforce(struct file * file, const char __user * buf,
101 size_t count, loff_t *ppos)
102
103 {
104 char *page;
105 ssize_t length;
106 int new_value;
107
108 if (count >= PAGE_SIZE)
109 return -ENOMEM;
110 if (*ppos != 0) {
111 /* No partial writes. */
112 return -EINVAL;
113 }
114 page = (char*)get_zeroed_page(GFP_KERNEL);
115 if (!page)
116 return -ENOMEM;
117 length = -EFAULT;
118 if (copy_from_user(page, buf, count))
119 goto out;
120
121 length = -EINVAL;
122 if (sscanf(page, "%d", &new_value) != 1)
123 goto out;
124
125 if (new_value != selinux_enforcing) {
126 length = task_has_security(current, SECURITY__SETENFORCE);
127 if (length)
128 goto out;
129 selinux_enforcing = new_value;
130 if (selinux_enforcing)
131 avc_ss_reset(0);
132 selnl_notify_setenforce(selinux_enforcing);
133 }
134 length = count;
135 out:
136 free_page((unsigned long) page);
137 return length;
138 }
139 #else
140 #define sel_write_enforce NULL
141 #endif
142
143 static struct file_operations sel_enforce_ops = {
144 .read = sel_read_enforce,
145 .write = sel_write_enforce,
146 };
147
148 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
149 static ssize_t sel_write_disable(struct file * file, const char __user * buf,
150 size_t count, loff_t *ppos)
151
152 {
153 char *page;
154 ssize_t length;
155 int new_value;
156 extern int selinux_disable(void);
157
158 if (count >= PAGE_SIZE)
159 return -ENOMEM;
160 if (*ppos != 0) {
161 /* No partial writes. */
162 return -EINVAL;
163 }
164 page = (char*)get_zeroed_page(GFP_KERNEL);
165 if (!page)
166 return -ENOMEM;
167 length = -EFAULT;
168 if (copy_from_user(page, buf, count))
169 goto out;
170
171 length = -EINVAL;
172 if (sscanf(page, "%d", &new_value) != 1)
173 goto out;
174
175 if (new_value) {
176 length = selinux_disable();
177 if (length < 0)
178 goto out;
179 }
180
181 length = count;
182 out:
183 free_page((unsigned long) page);
184 return length;
185 }
186 #else
187 #define sel_write_disable NULL
188 #endif
189
190 static struct file_operations sel_disable_ops = {
191 .write = sel_write_disable,
192 };
193
194 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
195 size_t count, loff_t *ppos)
196 {
197 char tmpbuf[TMPBUFLEN];
198 ssize_t length;
199
200 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
201 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
202 }
203
204 static struct file_operations sel_policyvers_ops = {
205 .read = sel_read_policyvers,
206 };
207
208 /* declaration for sel_write_load */
209 static int sel_make_bools(void);
210
211 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
212 size_t count, loff_t *ppos)
213 {
214 char tmpbuf[TMPBUFLEN];
215 ssize_t length;
216
217 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
218 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
219 }
220
221 static struct file_operations sel_mls_ops = {
222 .read = sel_read_mls,
223 };
224
225 static ssize_t sel_write_load(struct file * file, const char __user * buf,
226 size_t count, loff_t *ppos)
227
228 {
229 int ret;
230 ssize_t length;
231 void *data = NULL;
232
233 down(&sel_sem);
234
235 length = task_has_security(current, SECURITY__LOAD_POLICY);
236 if (length)
237 goto out;
238
239 if (*ppos != 0) {
240 /* No partial writes. */
241 length = -EINVAL;
242 goto out;
243 }
244
245 if ((count > 64 * 1024 * 1024)
246 || (data = vmalloc(count)) == NULL) {
247 length = -ENOMEM;
248 goto out;
249 }
250
251 length = -EFAULT;
252 if (copy_from_user(data, buf, count) != 0)
253 goto out;
254
255 length = security_load_policy(data, count);
256 if (length)
257 goto out;
258
259 ret = sel_make_bools();
260 if (ret)
261 length = ret;
262 else
263 length = count;
264 out:
265 up(&sel_sem);
266 vfree(data);
267 return length;
268 }
269
270 static struct file_operations sel_load_ops = {
271 .write = sel_write_load,
272 };
273
274
275 static ssize_t sel_write_context(struct file * file, const char __user * buf,
276 size_t count, loff_t *ppos)
277
278 {
279 char *page;
280 u32 sid;
281 ssize_t length;
282
283 length = task_has_security(current, SECURITY__CHECK_CONTEXT);
284 if (length)
285 return length;
286
287 if (count >= PAGE_SIZE)
288 return -ENOMEM;
289 if (*ppos != 0) {
290 /* No partial writes. */
291 return -EINVAL;
292 }
293 page = (char*)get_zeroed_page(GFP_KERNEL);
294 if (!page)
295 return -ENOMEM;
296 length = -EFAULT;
297 if (copy_from_user(page, buf, count))
298 goto out;
299
300 length = security_context_to_sid(page, count, &sid);
301 if (length < 0)
302 goto out;
303
304 length = count;
305 out:
306 free_page((unsigned long) page);
307 return length;
308 }
309
310 static struct file_operations sel_context_ops = {
311 .write = sel_write_context,
312 };
313
314 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
315 size_t count, loff_t *ppos)
316 {
317 char tmpbuf[TMPBUFLEN];
318 ssize_t length;
319
320 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
321 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
322 }
323
324 static ssize_t sel_write_checkreqprot(struct file * file, const char __user * buf,
325 size_t count, loff_t *ppos)
326 {
327 char *page;
328 ssize_t length;
329 unsigned int new_value;
330
331 length = task_has_security(current, SECURITY__SETCHECKREQPROT);
332 if (length)
333 return length;
334
335 if (count >= PAGE_SIZE)
336 return -ENOMEM;
337 if (*ppos != 0) {
338 /* No partial writes. */
339 return -EINVAL;
340 }
341 page = (char*)get_zeroed_page(GFP_KERNEL);
342 if (!page)
343 return -ENOMEM;
344 length = -EFAULT;
345 if (copy_from_user(page, buf, count))
346 goto out;
347
348 length = -EINVAL;
349 if (sscanf(page, "%u", &new_value) != 1)
350 goto out;
351
352 selinux_checkreqprot = new_value ? 1 : 0;
353 length = count;
354 out:
355 free_page((unsigned long) page);
356 return length;
357 }
358 static struct file_operations sel_checkreqprot_ops = {
359 .read = sel_read_checkreqprot,
360 .write = sel_write_checkreqprot,
361 };
362
363 /*
364 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
365 */
366 static ssize_t sel_write_access(struct file * file, char *buf, size_t size);
367 static ssize_t sel_write_create(struct file * file, char *buf, size_t size);
368 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size);
369 static ssize_t sel_write_user(struct file * file, char *buf, size_t size);
370 static ssize_t sel_write_member(struct file * file, char *buf, size_t size);
371
372 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
373 [SEL_ACCESS] = sel_write_access,
374 [SEL_CREATE] = sel_write_create,
375 [SEL_RELABEL] = sel_write_relabel,
376 [SEL_USER] = sel_write_user,
377 [SEL_MEMBER] = sel_write_member,
378 };
379
380 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
381 {
382 ino_t ino = file->f_dentry->d_inode->i_ino;
383 char *data;
384 ssize_t rv;
385
386 if (ino >= sizeof(write_op)/sizeof(write_op[0]) || !write_op[ino])
387 return -EINVAL;
388
389 data = simple_transaction_get(file, buf, size);
390 if (IS_ERR(data))
391 return PTR_ERR(data);
392
393 rv = write_op[ino](file, data, size);
394 if (rv>0) {
395 simple_transaction_set(file, rv);
396 rv = size;
397 }
398 return rv;
399 }
400
401 static struct file_operations transaction_ops = {
402 .write = selinux_transaction_write,
403 .read = simple_transaction_read,
404 .release = simple_transaction_release,
405 };
406
407 /*
408 * payload - write methods
409 * If the method has a response, the response should be put in buf,
410 * and the length returned. Otherwise return 0 or and -error.
411 */
412
413 static ssize_t sel_write_access(struct file * file, char *buf, size_t size)
414 {
415 char *scon, *tcon;
416 u32 ssid, tsid;
417 u16 tclass;
418 u32 req;
419 struct av_decision avd;
420 ssize_t length;
421
422 length = task_has_security(current, SECURITY__COMPUTE_AV);
423 if (length)
424 return length;
425
426 length = -ENOMEM;
427 scon = kzalloc(size+1, GFP_KERNEL);
428 if (!scon)
429 return length;
430
431 tcon = kzalloc(size+1, GFP_KERNEL);
432 if (!tcon)
433 goto out;
434
435 length = -EINVAL;
436 if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
437 goto out2;
438
439 length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
440 if (length < 0)
441 goto out2;
442 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
443 if (length < 0)
444 goto out2;
445
446 length = security_compute_av(ssid, tsid, tclass, req, &avd);
447 if (length < 0)
448 goto out2;
449
450 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
451 "%x %x %x %x %u",
452 avd.allowed, avd.decided,
453 avd.auditallow, avd.auditdeny,
454 avd.seqno);
455 out2:
456 kfree(tcon);
457 out:
458 kfree(scon);
459 return length;
460 }
461
462 static ssize_t sel_write_create(struct file * file, char *buf, size_t size)
463 {
464 char *scon, *tcon;
465 u32 ssid, tsid, newsid;
466 u16 tclass;
467 ssize_t length;
468 char *newcon;
469 u32 len;
470
471 length = task_has_security(current, SECURITY__COMPUTE_CREATE);
472 if (length)
473 return length;
474
475 length = -ENOMEM;
476 scon = kzalloc(size+1, GFP_KERNEL);
477 if (!scon)
478 return length;
479
480 tcon = kzalloc(size+1, GFP_KERNEL);
481 if (!tcon)
482 goto out;
483
484 length = -EINVAL;
485 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
486 goto out2;
487
488 length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
489 if (length < 0)
490 goto out2;
491 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
492 if (length < 0)
493 goto out2;
494
495 length = security_transition_sid(ssid, tsid, tclass, &newsid);
496 if (length < 0)
497 goto out2;
498
499 length = security_sid_to_context(newsid, &newcon, &len);
500 if (length < 0)
501 goto out2;
502
503 if (len > SIMPLE_TRANSACTION_LIMIT) {
504 printk(KERN_ERR "%s: context size (%u) exceeds payload "
505 "max\n", __FUNCTION__, len);
506 length = -ERANGE;
507 goto out3;
508 }
509
510 memcpy(buf, newcon, len);
511 length = len;
512 out3:
513 kfree(newcon);
514 out2:
515 kfree(tcon);
516 out:
517 kfree(scon);
518 return length;
519 }
520
521 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size)
522 {
523 char *scon, *tcon;
524 u32 ssid, tsid, newsid;
525 u16 tclass;
526 ssize_t length;
527 char *newcon;
528 u32 len;
529
530 length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
531 if (length)
532 return length;
533
534 length = -ENOMEM;
535 scon = kzalloc(size+1, GFP_KERNEL);
536 if (!scon)
537 return length;
538
539 tcon = kzalloc(size+1, GFP_KERNEL);
540 if (!tcon)
541 goto out;
542
543 length = -EINVAL;
544 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
545 goto out2;
546
547 length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
548 if (length < 0)
549 goto out2;
550 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
551 if (length < 0)
552 goto out2;
553
554 length = security_change_sid(ssid, tsid, tclass, &newsid);
555 if (length < 0)
556 goto out2;
557
558 length = security_sid_to_context(newsid, &newcon, &len);
559 if (length < 0)
560 goto out2;
561
562 if (len > SIMPLE_TRANSACTION_LIMIT) {
563 length = -ERANGE;
564 goto out3;
565 }
566
567 memcpy(buf, newcon, len);
568 length = len;
569 out3:
570 kfree(newcon);
571 out2:
572 kfree(tcon);
573 out:
574 kfree(scon);
575 return length;
576 }
577
578 static ssize_t sel_write_user(struct file * file, char *buf, size_t size)
579 {
580 char *con, *user, *ptr;
581 u32 sid, *sids;
582 ssize_t length;
583 char *newcon;
584 int i, rc;
585 u32 len, nsids;
586
587 length = task_has_security(current, SECURITY__COMPUTE_USER);
588 if (length)
589 return length;
590
591 length = -ENOMEM;
592 con = kzalloc(size+1, GFP_KERNEL);
593 if (!con)
594 return length;
595
596 user = kzalloc(size+1, GFP_KERNEL);
597 if (!user)
598 goto out;
599
600 length = -EINVAL;
601 if (sscanf(buf, "%s %s", con, user) != 2)
602 goto out2;
603
604 length = security_context_to_sid(con, strlen(con)+1, &sid);
605 if (length < 0)
606 goto out2;
607
608 length = security_get_user_sids(sid, user, &sids, &nsids);
609 if (length < 0)
610 goto out2;
611
612 length = sprintf(buf, "%u", nsids) + 1;
613 ptr = buf + length;
614 for (i = 0; i < nsids; i++) {
615 rc = security_sid_to_context(sids[i], &newcon, &len);
616 if (rc) {
617 length = rc;
618 goto out3;
619 }
620 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
621 kfree(newcon);
622 length = -ERANGE;
623 goto out3;
624 }
625 memcpy(ptr, newcon, len);
626 kfree(newcon);
627 ptr += len;
628 length += len;
629 }
630 out3:
631 kfree(sids);
632 out2:
633 kfree(user);
634 out:
635 kfree(con);
636 return length;
637 }
638
639 static ssize_t sel_write_member(struct file * file, char *buf, size_t size)
640 {
641 char *scon, *tcon;
642 u32 ssid, tsid, newsid;
643 u16 tclass;
644 ssize_t length;
645 char *newcon;
646 u32 len;
647
648 length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
649 if (length)
650 return length;
651
652 length = -ENOMEM;
653 scon = kzalloc(size+1, GFP_KERNEL);
654 if (!scon)
655 return length;
656
657 tcon = kzalloc(size+1, GFP_KERNEL);
658 if (!tcon)
659 goto out;
660
661 length = -EINVAL;
662 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
663 goto out2;
664
665 length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
666 if (length < 0)
667 goto out2;
668 length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
669 if (length < 0)
670 goto out2;
671
672 length = security_member_sid(ssid, tsid, tclass, &newsid);
673 if (length < 0)
674 goto out2;
675
676 length = security_sid_to_context(newsid, &newcon, &len);
677 if (length < 0)
678 goto out2;
679
680 if (len > SIMPLE_TRANSACTION_LIMIT) {
681 printk(KERN_ERR "%s: context size (%u) exceeds payload "
682 "max\n", __FUNCTION__, len);
683 length = -ERANGE;
684 goto out3;
685 }
686
687 memcpy(buf, newcon, len);
688 length = len;
689 out3:
690 kfree(newcon);
691 out2:
692 kfree(tcon);
693 out:
694 kfree(scon);
695 return length;
696 }
697
698 static struct inode *sel_make_inode(struct super_block *sb, int mode)
699 {
700 struct inode *ret = new_inode(sb);
701
702 if (ret) {
703 ret->i_mode = mode;
704 ret->i_uid = ret->i_gid = 0;
705 ret->i_blksize = PAGE_CACHE_SIZE;
706 ret->i_blocks = 0;
707 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
708 }
709 return ret;
710 }
711
712 #define BOOL_INO_OFFSET 30
713
714 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
715 size_t count, loff_t *ppos)
716 {
717 char *page = NULL;
718 ssize_t length;
719 ssize_t end;
720 ssize_t ret;
721 int cur_enforcing;
722 struct inode *inode;
723
724 down(&sel_sem);
725
726 ret = -EFAULT;
727
728 /* check to see if this file has been deleted */
729 if (!filep->f_op)
730 goto out;
731
732 if (count > PAGE_SIZE) {
733 ret = -EINVAL;
734 goto out;
735 }
736 if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) {
737 ret = -ENOMEM;
738 goto out;
739 }
740
741 inode = filep->f_dentry->d_inode;
742 cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET);
743 if (cur_enforcing < 0) {
744 ret = cur_enforcing;
745 goto out;
746 }
747
748 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
749 bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]);
750 if (length < 0) {
751 ret = length;
752 goto out;
753 }
754
755 if (*ppos >= length) {
756 ret = 0;
757 goto out;
758 }
759 if (count + *ppos > length)
760 count = length - *ppos;
761 end = count + *ppos;
762 if (copy_to_user(buf, (char *) page + *ppos, count)) {
763 ret = -EFAULT;
764 goto out;
765 }
766 *ppos = end;
767 ret = count;
768 out:
769 up(&sel_sem);
770 if (page)
771 free_page((unsigned long)page);
772 return ret;
773 }
774
775 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
776 size_t count, loff_t *ppos)
777 {
778 char *page = NULL;
779 ssize_t length = -EFAULT;
780 int new_value;
781 struct inode *inode;
782
783 down(&sel_sem);
784
785 length = task_has_security(current, SECURITY__SETBOOL);
786 if (length)
787 goto out;
788
789 /* check to see if this file has been deleted */
790 if (!filep->f_op)
791 goto out;
792
793 if (count >= PAGE_SIZE) {
794 length = -ENOMEM;
795 goto out;
796 }
797 if (*ppos != 0) {
798 /* No partial writes. */
799 goto out;
800 }
801 page = (char*)get_zeroed_page(GFP_KERNEL);
802 if (!page) {
803 length = -ENOMEM;
804 goto out;
805 }
806
807 if (copy_from_user(page, buf, count))
808 goto out;
809
810 length = -EINVAL;
811 if (sscanf(page, "%d", &new_value) != 1)
812 goto out;
813
814 if (new_value)
815 new_value = 1;
816
817 inode = filep->f_dentry->d_inode;
818 bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = new_value;
819 length = count;
820
821 out:
822 up(&sel_sem);
823 if (page)
824 free_page((unsigned long) page);
825 return length;
826 }
827
828 static struct file_operations sel_bool_ops = {
829 .read = sel_read_bool,
830 .write = sel_write_bool,
831 };
832
833 static ssize_t sel_commit_bools_write(struct file *filep,
834 const char __user *buf,
835 size_t count, loff_t *ppos)
836 {
837 char *page = NULL;
838 ssize_t length = -EFAULT;
839 int new_value;
840
841 down(&sel_sem);
842
843 length = task_has_security(current, SECURITY__SETBOOL);
844 if (length)
845 goto out;
846
847 /* check to see if this file has been deleted */
848 if (!filep->f_op)
849 goto out;
850
851 if (count >= PAGE_SIZE) {
852 length = -ENOMEM;
853 goto out;
854 }
855 if (*ppos != 0) {
856 /* No partial writes. */
857 goto out;
858 }
859 page = (char*)get_zeroed_page(GFP_KERNEL);
860 if (!page) {
861 length = -ENOMEM;
862 goto out;
863 }
864
865 if (copy_from_user(page, buf, count))
866 goto out;
867
868 length = -EINVAL;
869 if (sscanf(page, "%d", &new_value) != 1)
870 goto out;
871
872 if (new_value && bool_pending_values) {
873 security_set_bools(bool_num, bool_pending_values);
874 }
875
876 length = count;
877
878 out:
879 up(&sel_sem);
880 if (page)
881 free_page((unsigned long) page);
882 return length;
883 }
884
885 static struct file_operations sel_commit_bools_ops = {
886 .write = sel_commit_bools_write,
887 };
888
889 /* delete booleans - partial revoke() from
890 * fs/proc/generic.c proc_kill_inodes */
891 static void sel_remove_bools(struct dentry *de)
892 {
893 struct list_head *p, *node;
894 struct super_block *sb = de->d_sb;
895
896 spin_lock(&dcache_lock);
897 node = de->d_subdirs.next;
898 while (node != &de->d_subdirs) {
899 struct dentry *d = list_entry(node, struct dentry, d_child);
900 list_del_init(node);
901
902 if (d->d_inode) {
903 d = dget_locked(d);
904 spin_unlock(&dcache_lock);
905 d_delete(d);
906 simple_unlink(de->d_inode, d);
907 dput(d);
908 spin_lock(&dcache_lock);
909 }
910 node = de->d_subdirs.next;
911 }
912
913 spin_unlock(&dcache_lock);
914
915 file_list_lock();
916 list_for_each(p, &sb->s_files) {
917 struct file * filp = list_entry(p, struct file, f_u.fu_list);
918 struct dentry * dentry = filp->f_dentry;
919
920 if (dentry->d_parent != de) {
921 continue;
922 }
923 filp->f_op = NULL;
924 }
925 file_list_unlock();
926 }
927
928 #define BOOL_DIR_NAME "booleans"
929
930 static int sel_make_bools(void)
931 {
932 int i, ret = 0;
933 ssize_t len;
934 struct dentry *dentry = NULL;
935 struct dentry *dir = bool_dir;
936 struct inode *inode = NULL;
937 struct inode_security_struct *isec;
938 char **names = NULL, *page;
939 int num;
940 int *values = NULL;
941 u32 sid;
942
943 /* remove any existing files */
944 kfree(bool_pending_values);
945 bool_pending_values = NULL;
946
947 sel_remove_bools(dir);
948
949 if (!(page = (char*)get_zeroed_page(GFP_KERNEL)))
950 return -ENOMEM;
951
952 ret = security_get_bools(&num, &names, &values);
953 if (ret != 0)
954 goto out;
955
956 for (i = 0; i < num; i++) {
957 dentry = d_alloc_name(dir, names[i]);
958 if (!dentry) {
959 ret = -ENOMEM;
960 goto err;
961 }
962 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
963 if (!inode) {
964 ret = -ENOMEM;
965 goto err;
966 }
967
968 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
969 if (len < 0) {
970 ret = -EINVAL;
971 goto err;
972 } else if (len >= PAGE_SIZE) {
973 ret = -ENAMETOOLONG;
974 goto err;
975 }
976 isec = (struct inode_security_struct*)inode->i_security;
977 if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid)))
978 goto err;
979 isec->sid = sid;
980 isec->initialized = 1;
981 inode->i_fop = &sel_bool_ops;
982 inode->i_ino = i + BOOL_INO_OFFSET;
983 d_add(dentry, inode);
984 }
985 bool_num = num;
986 bool_pending_values = values;
987 out:
988 free_page((unsigned long)page);
989 if (names) {
990 for (i = 0; i < num; i++)
991 kfree(names[i]);
992 kfree(names);
993 }
994 return ret;
995 err:
996 kfree(values);
997 d_genocide(dir);
998 ret = -ENOMEM;
999 goto out;
1000 }
1001
1002 #define NULL_FILE_NAME "null"
1003
1004 struct dentry *selinux_null = NULL;
1005
1006 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1007 size_t count, loff_t *ppos)
1008 {
1009 char tmpbuf[TMPBUFLEN];
1010 ssize_t length;
1011
1012 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1013 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1014 }
1015
1016 static ssize_t sel_write_avc_cache_threshold(struct file * file,
1017 const char __user * buf,
1018 size_t count, loff_t *ppos)
1019
1020 {
1021 char *page;
1022 ssize_t ret;
1023 int new_value;
1024
1025 if (count >= PAGE_SIZE) {
1026 ret = -ENOMEM;
1027 goto out;
1028 }
1029
1030 if (*ppos != 0) {
1031 /* No partial writes. */
1032 ret = -EINVAL;
1033 goto out;
1034 }
1035
1036 page = (char*)get_zeroed_page(GFP_KERNEL);
1037 if (!page) {
1038 ret = -ENOMEM;
1039 goto out;
1040 }
1041
1042 if (copy_from_user(page, buf, count)) {
1043 ret = -EFAULT;
1044 goto out_free;
1045 }
1046
1047 if (sscanf(page, "%u", &new_value) != 1) {
1048 ret = -EINVAL;
1049 goto out;
1050 }
1051
1052 if (new_value != avc_cache_threshold) {
1053 ret = task_has_security(current, SECURITY__SETSECPARAM);
1054 if (ret)
1055 goto out_free;
1056 avc_cache_threshold = new_value;
1057 }
1058 ret = count;
1059 out_free:
1060 free_page((unsigned long)page);
1061 out:
1062 return ret;
1063 }
1064
1065 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1066 size_t count, loff_t *ppos)
1067 {
1068 char *page;
1069 ssize_t ret = 0;
1070
1071 page = (char *)__get_free_page(GFP_KERNEL);
1072 if (!page) {
1073 ret = -ENOMEM;
1074 goto out;
1075 }
1076 ret = avc_get_hash_stats(page);
1077 if (ret >= 0)
1078 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1079 free_page((unsigned long)page);
1080 out:
1081 return ret;
1082 }
1083
1084 static struct file_operations sel_avc_cache_threshold_ops = {
1085 .read = sel_read_avc_cache_threshold,
1086 .write = sel_write_avc_cache_threshold,
1087 };
1088
1089 static struct file_operations sel_avc_hash_stats_ops = {
1090 .read = sel_read_avc_hash_stats,
1091 };
1092
1093 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1094 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1095 {
1096 int cpu;
1097
1098 for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1099 if (!cpu_possible(cpu))
1100 continue;
1101 *idx = cpu + 1;
1102 return &per_cpu(avc_cache_stats, cpu);
1103 }
1104 return NULL;
1105 }
1106
1107 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1108 {
1109 loff_t n = *pos - 1;
1110
1111 if (*pos == 0)
1112 return SEQ_START_TOKEN;
1113
1114 return sel_avc_get_stat_idx(&n);
1115 }
1116
1117 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1118 {
1119 return sel_avc_get_stat_idx(pos);
1120 }
1121
1122 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1123 {
1124 struct avc_cache_stats *st = v;
1125
1126 if (v == SEQ_START_TOKEN)
1127 seq_printf(seq, "lookups hits misses allocations reclaims "
1128 "frees\n");
1129 else
1130 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1131 st->hits, st->misses, st->allocations,
1132 st->reclaims, st->frees);
1133 return 0;
1134 }
1135
1136 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1137 { }
1138
1139 static struct seq_operations sel_avc_cache_stats_seq_ops = {
1140 .start = sel_avc_stats_seq_start,
1141 .next = sel_avc_stats_seq_next,
1142 .show = sel_avc_stats_seq_show,
1143 .stop = sel_avc_stats_seq_stop,
1144 };
1145
1146 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1147 {
1148 return seq_open(file, &sel_avc_cache_stats_seq_ops);
1149 }
1150
1151 static struct file_operations sel_avc_cache_stats_ops = {
1152 .open = sel_open_avc_cache_stats,
1153 .read = seq_read,
1154 .llseek = seq_lseek,
1155 .release = seq_release,
1156 };
1157 #endif
1158
1159 static int sel_make_avc_files(struct dentry *dir)
1160 {
1161 int i, ret = 0;
1162 static struct tree_descr files[] = {
1163 { "cache_threshold",
1164 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1165 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1166 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1167 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1168 #endif
1169 };
1170
1171 for (i = 0; i < sizeof (files) / sizeof (files[0]); i++) {
1172 struct inode *inode;
1173 struct dentry *dentry;
1174
1175 dentry = d_alloc_name(dir, files[i].name);
1176 if (!dentry) {
1177 ret = -ENOMEM;
1178 goto err;
1179 }
1180
1181 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1182 if (!inode) {
1183 ret = -ENOMEM;
1184 goto err;
1185 }
1186 inode->i_fop = files[i].ops;
1187 d_add(dentry, inode);
1188 }
1189 out:
1190 return ret;
1191 err:
1192 d_genocide(dir);
1193 goto out;
1194 }
1195
1196 static int sel_make_dir(struct super_block *sb, struct dentry *dentry)
1197 {
1198 int ret = 0;
1199 struct inode *inode;
1200
1201 inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1202 if (!inode) {
1203 ret = -ENOMEM;
1204 goto out;
1205 }
1206 inode->i_op = &simple_dir_inode_operations;
1207 inode->i_fop = &simple_dir_operations;
1208 d_add(dentry, inode);
1209 out:
1210 return ret;
1211 }
1212
1213 static int sel_fill_super(struct super_block * sb, void * data, int silent)
1214 {
1215 int ret;
1216 struct dentry *dentry;
1217 struct inode *inode;
1218 struct inode_security_struct *isec;
1219
1220 static struct tree_descr selinux_files[] = {
1221 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1222 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1223 [SEL_CONTEXT] = {"context", &sel_context_ops, S_IRUGO|S_IWUGO},
1224 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1225 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1226 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1227 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1228 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1229 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1230 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1231 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1232 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1233 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1234 /* last one */ {""}
1235 };
1236 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1237 if (ret)
1238 return ret;
1239
1240 dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1241 if (!dentry)
1242 return -ENOMEM;
1243
1244 inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1245 if (!inode)
1246 goto out;
1247 inode->i_op = &simple_dir_inode_operations;
1248 inode->i_fop = &simple_dir_operations;
1249 d_add(dentry, inode);
1250 bool_dir = dentry;
1251 ret = sel_make_bools();
1252 if (ret)
1253 goto out;
1254
1255 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1256 if (!dentry)
1257 return -ENOMEM;
1258
1259 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1260 if (!inode)
1261 goto out;
1262 isec = (struct inode_security_struct*)inode->i_security;
1263 isec->sid = SECINITSID_DEVNULL;
1264 isec->sclass = SECCLASS_CHR_FILE;
1265 isec->initialized = 1;
1266
1267 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1268 d_add(dentry, inode);
1269 selinux_null = dentry;
1270
1271 dentry = d_alloc_name(sb->s_root, "avc");
1272 if (!dentry)
1273 return -ENOMEM;
1274
1275 ret = sel_make_dir(sb, dentry);
1276 if (ret)
1277 goto out;
1278
1279 ret = sel_make_avc_files(dentry);
1280 if (ret)
1281 goto out;
1282
1283 return 0;
1284 out:
1285 dput(dentry);
1286 printk(KERN_ERR "%s: failed while creating inodes\n", __FUNCTION__);
1287 return -ENOMEM;
1288 }
1289
1290 static struct super_block *sel_get_sb(struct file_system_type *fs_type,
1291 int flags, const char *dev_name, void *data)
1292 {
1293 return get_sb_single(fs_type, flags, data, sel_fill_super);
1294 }
1295
1296 static struct file_system_type sel_fs_type = {
1297 .name = "selinuxfs",
1298 .get_sb = sel_get_sb,
1299 .kill_sb = kill_litter_super,
1300 };
1301
1302 struct vfsmount *selinuxfs_mount;
1303
1304 static int __init init_sel_fs(void)
1305 {
1306 int err;
1307
1308 if (!selinux_enabled)
1309 return 0;
1310 err = register_filesystem(&sel_fs_type);
1311 if (!err) {
1312 selinuxfs_mount = kern_mount(&sel_fs_type);
1313 if (IS_ERR(selinuxfs_mount)) {
1314 printk(KERN_ERR "selinuxfs: could not mount!\n");
1315 err = PTR_ERR(selinuxfs_mount);
1316 selinuxfs_mount = NULL;
1317 }
1318 }
1319 return err;
1320 }
1321
1322 __initcall(init_sel_fs);
1323
1324 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1325 void exit_sel_fs(void)
1326 {
1327 unregister_filesystem(&sel_fs_type);
1328 }
1329 #endif
SocketAccessConTroL development