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support hardened usercopy
[cor.git] / security / selinux / selinuxfs.c
blobee94fa469c29edb0fbfc07d151d91710df86b265
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
3 *
4 * Added conditional policy language extensions
5 *
6 * Updated: Hewlett-Packard <paul@paul-moore.com>
7 *
8 * Added support for the policy capability bitmap
9 *
10 * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
11 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
12 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/pagemap.h>
17 #include <linux/slab.h>
18 #include <linux/vmalloc.h>
19 #include <linux/fs.h>
20 #include <linux/fs_context.h>
21 #include <linux/mount.h>
22 #include <linux/mutex.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/security.h>
26 #include <linux/major.h>
27 #include <linux/seq_file.h>
28 #include <linux/percpu.h>
29 #include <linux/audit.h>
30 #include <linux/uaccess.h>
31 #include <linux/kobject.h>
32 #include <linux/ctype.h>
33
34 /* selinuxfs pseudo filesystem for exporting the security policy API.
35 Based on the proc code and the fs/nfsd/nfsctl.c code. */
36
37 #include "flask.h"
38 #include "avc.h"
39 #include "avc_ss.h"
40 #include "security.h"
41 #include "objsec.h"
42 #include "conditional.h"
43
44 enum sel_inos {
45 SEL_ROOT_INO = 2,
46 SEL_LOAD, /* load policy */
47 SEL_ENFORCE, /* get or set enforcing status */
48 SEL_CONTEXT, /* validate context */
49 SEL_ACCESS, /* compute access decision */
50 SEL_CREATE, /* compute create labeling decision */
51 SEL_RELABEL, /* compute relabeling decision */
52 SEL_USER, /* compute reachable user contexts */
53 SEL_POLICYVERS, /* return policy version for this kernel */
54 SEL_COMMIT_BOOLS, /* commit new boolean values */
55 SEL_MLS, /* return if MLS policy is enabled */
56 SEL_DISABLE, /* disable SELinux until next reboot */
57 SEL_MEMBER, /* compute polyinstantiation membership decision */
58 SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
59 SEL_COMPAT_NET, /* whether to use old compat network packet controls */
60 SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
61 SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
62 SEL_STATUS, /* export current status using mmap() */
63 SEL_POLICY, /* allow userspace to read the in kernel policy */
64 SEL_VALIDATE_TRANS, /* compute validatetrans decision */
65 SEL_INO_NEXT, /* The next inode number to use */
66 };
67
68 struct selinux_fs_info {
69 struct dentry *bool_dir;
70 unsigned int bool_num;
71 char **bool_pending_names;
72 unsigned int *bool_pending_values;
73 struct dentry *class_dir;
74 unsigned long last_class_ino;
75 bool policy_opened;
76 struct dentry *policycap_dir;
77 struct mutex mutex;
78 unsigned long last_ino;
79 struct selinux_state *state;
80 struct super_block *sb;
81 };
82
83 static int selinux_fs_info_create(struct super_block *sb)
84 {
85 struct selinux_fs_info *fsi;
86
87 fsi = kzalloc(sizeof(*fsi), GFP_KERNEL);
88 if (!fsi)
89 return -ENOMEM;
90
91 mutex_init(&fsi->mutex);
92 fsi->last_ino = SEL_INO_NEXT - 1;
93 fsi->state = &selinux_state;
94 fsi->sb = sb;
95 sb->s_fs_info = fsi;
96 return 0;
97 }
98
99 static void selinux_fs_info_free(struct super_block *sb)
100 {
101 struct selinux_fs_info *fsi = sb->s_fs_info;
102 int i;
103
104 if (fsi) {
105 for (i = 0; i < fsi->bool_num; i++)
106 kfree(fsi->bool_pending_names[i]);
107 kfree(fsi->bool_pending_names);
108 kfree(fsi->bool_pending_values);
109 }
110 kfree(sb->s_fs_info);
111 sb->s_fs_info = NULL;
112 }
113
114 #define SEL_INITCON_INO_OFFSET 0x01000000
115 #define SEL_BOOL_INO_OFFSET 0x02000000
116 #define SEL_CLASS_INO_OFFSET 0x04000000
117 #define SEL_POLICYCAP_INO_OFFSET 0x08000000
118 #define SEL_INO_MASK 0x00ffffff
119
120 #define TMPBUFLEN 12
121 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
122 size_t count, loff_t *ppos)
123 {
124 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
125 char tmpbuf[TMPBUFLEN];
126 ssize_t length;
127
128 length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
129 enforcing_enabled(fsi->state));
130 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
131 }
132
133 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
134 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
135 size_t count, loff_t *ppos)
136
137 {
138 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
139 struct selinux_state *state = fsi->state;
140 char *page = NULL;
141 ssize_t length;
142 int old_value, new_value;
143
144 if (count >= PAGE_SIZE)
145 return -ENOMEM;
146
147 /* No partial writes. */
148 if (*ppos != 0)
149 return -EINVAL;
150
151 page = memdup_user_nul(buf, count);
152 if (IS_ERR(page))
153 return PTR_ERR(page);
154
155 length = -EINVAL;
156 if (sscanf(page, "%d", &new_value) != 1)
157 goto out;
158
159 new_value = !!new_value;
160
161 old_value = enforcing_enabled(state);
162 if (new_value != old_value) {
163 length = avc_has_perm(&selinux_state,
164 current_sid(), SECINITSID_SECURITY,
165 SECCLASS_SECURITY, SECURITY__SETENFORCE,
166 NULL);
167 if (length)
168 goto out;
169 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
170 "enforcing=%d old_enforcing=%d auid=%u ses=%u"
171 " enabled=%d old-enabled=%d lsm=selinux res=1",
172 new_value, old_value,
173 from_kuid(&init_user_ns, audit_get_loginuid(current)),
174 audit_get_sessionid(current),
175 selinux_enabled, selinux_enabled);
176 enforcing_set(state, new_value);
177 if (new_value)
178 avc_ss_reset(state->avc, 0);
179 selnl_notify_setenforce(new_value);
180 selinux_status_update_setenforce(state, new_value);
181 if (!new_value)
182 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
183 }
184 length = count;
185 out:
186 kfree(page);
187 return length;
188 }
189 #else
190 #define sel_write_enforce NULL
191 #endif
192
193 static const struct file_operations sel_enforce_ops = {
194 .read = sel_read_enforce,
195 .write = sel_write_enforce,
196 .llseek = generic_file_llseek,
197 };
198
199 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
200 size_t count, loff_t *ppos)
201 {
202 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
203 struct selinux_state *state = fsi->state;
204 char tmpbuf[TMPBUFLEN];
205 ssize_t length;
206 ino_t ino = file_inode(filp)->i_ino;
207 int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
208 security_get_reject_unknown(state) :
209 !security_get_allow_unknown(state);
210
211 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
212 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
213 }
214
215 static const struct file_operations sel_handle_unknown_ops = {
216 .read = sel_read_handle_unknown,
217 .llseek = generic_file_llseek,
218 };
219
220 static int sel_open_handle_status(struct inode *inode, struct file *filp)
221 {
222 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
223 struct page *status = selinux_kernel_status_page(fsi->state);
224
225 if (!status)
226 return -ENOMEM;
227
228 filp->private_data = status;
229
230 return 0;
231 }
232
233 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
234 size_t count, loff_t *ppos)
235 {
236 struct page *status = filp->private_data;
237
238 BUG_ON(!status);
239
240 return simple_read_from_buffer(buf, count, ppos,
241 page_address(status),
242 sizeof(struct selinux_kernel_status));
243 }
244
245 static int sel_mmap_handle_status(struct file *filp,
246 struct vm_area_struct *vma)
247 {
248 struct page *status = filp->private_data;
249 unsigned long size = vma->vm_end - vma->vm_start;
250
251 BUG_ON(!status);
252
253 /* only allows one page from the head */
254 if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
255 return -EIO;
256 /* disallow writable mapping */
257 if (vma->vm_flags & VM_WRITE)
258 return -EPERM;
259 /* disallow mprotect() turns it into writable */
260 vma->vm_flags &= ~VM_MAYWRITE;
261
262 return remap_pfn_range(vma, vma->vm_start,
263 page_to_pfn(status),
264 size, vma->vm_page_prot);
265 }
266
267 static const struct file_operations sel_handle_status_ops = {
268 .open = sel_open_handle_status,
269 .read = sel_read_handle_status,
270 .mmap = sel_mmap_handle_status,
271 .llseek = generic_file_llseek,
272 };
273
274 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
275 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
276 size_t count, loff_t *ppos)
277
278 {
279 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
280 char *page;
281 ssize_t length;
282 int new_value;
283 int enforcing;
284
285 if (count >= PAGE_SIZE)
286 return -ENOMEM;
287
288 /* No partial writes. */
289 if (*ppos != 0)
290 return -EINVAL;
291
292 page = memdup_user_nul(buf, count);
293 if (IS_ERR(page))
294 return PTR_ERR(page);
295
296 length = -EINVAL;
297 if (sscanf(page, "%d", &new_value) != 1)
298 goto out;
299
300 if (new_value) {
301 enforcing = enforcing_enabled(fsi->state);
302 length = selinux_disable(fsi->state);
303 if (length)
304 goto out;
305 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
306 "enforcing=%d old_enforcing=%d auid=%u ses=%u"
307 " enabled=%d old-enabled=%d lsm=selinux res=1",
308 enforcing, enforcing,
309 from_kuid(&init_user_ns, audit_get_loginuid(current)),
310 audit_get_sessionid(current), 0, 1);
311 }
312
313 length = count;
314 out:
315 kfree(page);
316 return length;
317 }
318 #else
319 #define sel_write_disable NULL
320 #endif
321
322 static const struct file_operations sel_disable_ops = {
323 .write = sel_write_disable,
324 .llseek = generic_file_llseek,
325 };
326
327 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
328 size_t count, loff_t *ppos)
329 {
330 char tmpbuf[TMPBUFLEN];
331 ssize_t length;
332
333 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
334 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
335 }
336
337 static const struct file_operations sel_policyvers_ops = {
338 .read = sel_read_policyvers,
339 .llseek = generic_file_llseek,
340 };
341
342 /* declaration for sel_write_load */
343 static int sel_make_bools(struct selinux_fs_info *fsi);
344 static int sel_make_classes(struct selinux_fs_info *fsi);
345 static int sel_make_policycap(struct selinux_fs_info *fsi);
346
347 /* declaration for sel_make_class_dirs */
348 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
349 unsigned long *ino);
350
351 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
352 size_t count, loff_t *ppos)
353 {
354 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
355 char tmpbuf[TMPBUFLEN];
356 ssize_t length;
357
358 length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
359 security_mls_enabled(fsi->state));
360 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
361 }
362
363 static const struct file_operations sel_mls_ops = {
364 .read = sel_read_mls,
365 .llseek = generic_file_llseek,
366 };
367
368 struct policy_load_memory {
369 size_t len;
370 void *data;
371 };
372
373 static int sel_open_policy(struct inode *inode, struct file *filp)
374 {
375 struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
376 struct selinux_state *state = fsi->state;
377 struct policy_load_memory *plm = NULL;
378 int rc;
379
380 BUG_ON(filp->private_data);
381
382 mutex_lock(&fsi->mutex);
383
384 rc = avc_has_perm(&selinux_state,
385 current_sid(), SECINITSID_SECURITY,
386 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
387 if (rc)
388 goto err;
389
390 rc = -EBUSY;
391 if (fsi->policy_opened)
392 goto err;
393
394 rc = -ENOMEM;
395 plm = kzalloc(sizeof(*plm), GFP_KERNEL);
396 if (!plm)
397 goto err;
398
399 if (i_size_read(inode) != security_policydb_len(state)) {
400 inode_lock(inode);
401 i_size_write(inode, security_policydb_len(state));
402 inode_unlock(inode);
403 }
404
405 rc = security_read_policy(state, &plm->data, &plm->len);
406 if (rc)
407 goto err;
408
409 fsi->policy_opened = 1;
410
411 filp->private_data = plm;
412
413 mutex_unlock(&fsi->mutex);
414
415 return 0;
416 err:
417 mutex_unlock(&fsi->mutex);
418
419 if (plm)
420 vfree(plm->data);
421 kfree(plm);
422 return rc;
423 }
424
425 static int sel_release_policy(struct inode *inode, struct file *filp)
426 {
427 struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
428 struct policy_load_memory *plm = filp->private_data;
429
430 BUG_ON(!plm);
431
432 fsi->policy_opened = 0;
433
434 vfree(plm->data);
435 kfree(plm);
436
437 return 0;
438 }
439
440 static ssize_t sel_read_policy(struct file *filp, char __user *buf,
441 size_t count, loff_t *ppos)
442 {
443 struct policy_load_memory *plm = filp->private_data;
444 int ret;
445
446 ret = avc_has_perm(&selinux_state,
447 current_sid(), SECINITSID_SECURITY,
448 SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
449 if (ret)
450 return ret;
451
452 return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
453 }
454
455 static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
456 {
457 struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
458 unsigned long offset;
459 struct page *page;
460
461 if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
462 return VM_FAULT_SIGBUS;
463
464 offset = vmf->pgoff << PAGE_SHIFT;
465 if (offset >= roundup(plm->len, PAGE_SIZE))
466 return VM_FAULT_SIGBUS;
467
468 page = vmalloc_to_page(plm->data + offset);
469 get_page(page);
470
471 vmf->page = page;
472
473 return 0;
474 }
475
476 static const struct vm_operations_struct sel_mmap_policy_ops = {
477 .fault = sel_mmap_policy_fault,
478 .page_mkwrite = sel_mmap_policy_fault,
479 };
480
481 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
482 {
483 if (vma->vm_flags & VM_SHARED) {
484 /* do not allow mprotect to make mapping writable */
485 vma->vm_flags &= ~VM_MAYWRITE;
486
487 if (vma->vm_flags & VM_WRITE)
488 return -EACCES;
489 }
490
491 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
492 vma->vm_ops = &sel_mmap_policy_ops;
493
494 return 0;
495 }
496
497 static const struct file_operations sel_policy_ops = {
498 .open = sel_open_policy,
499 .read = sel_read_policy,
500 .mmap = sel_mmap_policy,
501 .release = sel_release_policy,
502 .llseek = generic_file_llseek,
503 };
504
505 static int sel_make_policy_nodes(struct selinux_fs_info *fsi)
506 {
507 int ret;
508
509 ret = sel_make_bools(fsi);
510 if (ret) {
511 pr_err("SELinux: failed to load policy booleans\n");
512 return ret;
513 }
514
515 ret = sel_make_classes(fsi);
516 if (ret) {
517 pr_err("SELinux: failed to load policy classes\n");
518 return ret;
519 }
520
521 ret = sel_make_policycap(fsi);
522 if (ret) {
523 pr_err("SELinux: failed to load policy capabilities\n");
524 return ret;
525 }
526
527 return 0;
528 }
529
530 static ssize_t sel_write_load(struct file *file, const char __user *buf,
531 size_t count, loff_t *ppos)
532
533 {
534 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
535 ssize_t length;
536 void *data = NULL;
537
538 mutex_lock(&fsi->mutex);
539
540 length = avc_has_perm(&selinux_state,
541 current_sid(), SECINITSID_SECURITY,
542 SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
543 if (length)
544 goto out;
545
546 /* No partial writes. */
547 length = -EINVAL;
548 if (*ppos != 0)
549 goto out;
550
551 length = -ENOMEM;
552 data = vmalloc(count);
553 if (!data)
554 goto out;
555
556 length = -EFAULT;
557 if (copy_from_user(data, buf, count) != 0)
558 goto out;
559
560 length = security_load_policy(fsi->state, data, count);
561 if (length) {
562 pr_warn_ratelimited("SELinux: failed to load policy\n");
563 goto out;
564 }
565
566 length = sel_make_policy_nodes(fsi);
567 if (length)
568 goto out1;
569
570 length = count;
571
572 out1:
573 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
574 "auid=%u ses=%u lsm=selinux res=1",
575 from_kuid(&init_user_ns, audit_get_loginuid(current)),
576 audit_get_sessionid(current));
577 out:
578 mutex_unlock(&fsi->mutex);
579 vfree(data);
580 return length;
581 }
582
583 static const struct file_operations sel_load_ops = {
584 .write = sel_write_load,
585 .llseek = generic_file_llseek,
586 };
587
588 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
589 {
590 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
591 struct selinux_state *state = fsi->state;
592 char *canon = NULL;
593 u32 sid, len;
594 ssize_t length;
595
596 length = avc_has_perm(&selinux_state,
597 current_sid(), SECINITSID_SECURITY,
598 SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
599 if (length)
600 goto out;
601
602 length = security_context_to_sid(state, buf, size, &sid, GFP_KERNEL);
603 if (length)
604 goto out;
605
606 length = security_sid_to_context(state, sid, &canon, &len);
607 if (length)
608 goto out;
609
610 length = -ERANGE;
611 if (len > SIMPLE_TRANSACTION_LIMIT) {
612 pr_err("SELinux: %s: context size (%u) exceeds "
613 "payload max\n", __func__, len);
614 goto out;
615 }
616
617 memcpy(buf, canon, len);
618 length = len;
619 out:
620 kfree(canon);
621 return length;
622 }
623
624 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
625 size_t count, loff_t *ppos)
626 {
627 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
628 char tmpbuf[TMPBUFLEN];
629 ssize_t length;
630
631 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", fsi->state->checkreqprot);
632 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
633 }
634
635 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
636 size_t count, loff_t *ppos)
637 {
638 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
639 char *page;
640 ssize_t length;
641 unsigned int new_value;
642
643 length = avc_has_perm(&selinux_state,
644 current_sid(), SECINITSID_SECURITY,
645 SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
646 NULL);
647 if (length)
648 return length;
649
650 if (count >= PAGE_SIZE)
651 return -ENOMEM;
652
653 /* No partial writes. */
654 if (*ppos != 0)
655 return -EINVAL;
656
657 page = memdup_user_nul(buf, count);
658 if (IS_ERR(page))
659 return PTR_ERR(page);
660
661 length = -EINVAL;
662 if (sscanf(page, "%u", &new_value) != 1)
663 goto out;
664
665 fsi->state->checkreqprot = new_value ? 1 : 0;
666 length = count;
667 out:
668 kfree(page);
669 return length;
670 }
671 static const struct file_operations sel_checkreqprot_ops = {
672 .read = sel_read_checkreqprot,
673 .write = sel_write_checkreqprot,
674 .llseek = generic_file_llseek,
675 };
676
677 static ssize_t sel_write_validatetrans(struct file *file,
678 const char __user *buf,
679 size_t count, loff_t *ppos)
680 {
681 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
682 struct selinux_state *state = fsi->state;
683 char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
684 char *req = NULL;
685 u32 osid, nsid, tsid;
686 u16 tclass;
687 int rc;
688
689 rc = avc_has_perm(&selinux_state,
690 current_sid(), SECINITSID_SECURITY,
691 SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
692 if (rc)
693 goto out;
694
695 rc = -ENOMEM;
696 if (count >= PAGE_SIZE)
697 goto out;
698
699 /* No partial writes. */
700 rc = -EINVAL;
701 if (*ppos != 0)
702 goto out;
703
704 req = memdup_user_nul(buf, count);
705 if (IS_ERR(req)) {
706 rc = PTR_ERR(req);
707 req = NULL;
708 goto out;
709 }
710
711 rc = -ENOMEM;
712 oldcon = kzalloc(count + 1, GFP_KERNEL);
713 if (!oldcon)
714 goto out;
715
716 newcon = kzalloc(count + 1, GFP_KERNEL);
717 if (!newcon)
718 goto out;
719
720 taskcon = kzalloc(count + 1, GFP_KERNEL);
721 if (!taskcon)
722 goto out;
723
724 rc = -EINVAL;
725 if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
726 goto out;
727
728 rc = security_context_str_to_sid(state, oldcon, &osid, GFP_KERNEL);
729 if (rc)
730 goto out;
731
732 rc = security_context_str_to_sid(state, newcon, &nsid, GFP_KERNEL);
733 if (rc)
734 goto out;
735
736 rc = security_context_str_to_sid(state, taskcon, &tsid, GFP_KERNEL);
737 if (rc)
738 goto out;
739
740 rc = security_validate_transition_user(state, osid, nsid, tsid, tclass);
741 if (!rc)
742 rc = count;
743 out:
744 kfree(req);
745 kfree(oldcon);
746 kfree(newcon);
747 kfree(taskcon);
748 return rc;
749 }
750
751 static const struct file_operations sel_transition_ops = {
752 .write = sel_write_validatetrans,
753 .llseek = generic_file_llseek,
754 };
755
756 /*
757 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
758 */
759 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
760 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
761 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
762 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
763 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
764
765 static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
766 [SEL_ACCESS] = sel_write_access,
767 [SEL_CREATE] = sel_write_create,
768 [SEL_RELABEL] = sel_write_relabel,
769 [SEL_USER] = sel_write_user,
770 [SEL_MEMBER] = sel_write_member,
771 [SEL_CONTEXT] = sel_write_context,
772 };
773
774 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
775 {
776 ino_t ino = file_inode(file)->i_ino;
777 char *data;
778 ssize_t rv;
779
780 if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
781 return -EINVAL;
782
783 data = simple_transaction_get(file, buf, size);
784 if (IS_ERR(data))
785 return PTR_ERR(data);
786
787 rv = write_op[ino](file, data, size);
788 if (rv > 0) {
789 simple_transaction_set(file, rv);
790 rv = size;
791 }
792 return rv;
793 }
794
795 static const struct file_operations transaction_ops = {
796 .write = selinux_transaction_write,
797 .read = simple_transaction_read,
798 .release = simple_transaction_release,
799 .llseek = generic_file_llseek,
800 };
801
802 /*
803 * payload - write methods
804 * If the method has a response, the response should be put in buf,
805 * and the length returned. Otherwise return 0 or and -error.
806 */
807
808 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
809 {
810 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
811 struct selinux_state *state = fsi->state;
812 char *scon = NULL, *tcon = NULL;
813 u32 ssid, tsid;
814 u16 tclass;
815 struct av_decision avd;
816 ssize_t length;
817
818 length = avc_has_perm(&selinux_state,
819 current_sid(), SECINITSID_SECURITY,
820 SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
821 if (length)
822 goto out;
823
824 length = -ENOMEM;
825 scon = kzalloc(size + 1, GFP_KERNEL);
826 if (!scon)
827 goto out;
828
829 length = -ENOMEM;
830 tcon = kzalloc(size + 1, GFP_KERNEL);
831 if (!tcon)
832 goto out;
833
834 length = -EINVAL;
835 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
836 goto out;
837
838 length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
839 if (length)
840 goto out;
841
842 length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
843 if (length)
844 goto out;
845
846 security_compute_av_user(state, ssid, tsid, tclass, &avd);
847
848 length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
849 "%x %x %x %x %u %x",
850 avd.allowed, 0xffffffff,
851 avd.auditallow, avd.auditdeny,
852 avd.seqno, avd.flags);
853 out:
854 kfree(tcon);
855 kfree(scon);
856 return length;
857 }
858
859 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
860 {
861 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
862 struct selinux_state *state = fsi->state;
863 char *scon = NULL, *tcon = NULL;
864 char *namebuf = NULL, *objname = NULL;
865 u32 ssid, tsid, newsid;
866 u16 tclass;
867 ssize_t length;
868 char *newcon = NULL;
869 u32 len;
870 int nargs;
871
872 length = avc_has_perm(&selinux_state,
873 current_sid(), SECINITSID_SECURITY,
874 SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
875 NULL);
876 if (length)
877 goto out;
878
879 length = -ENOMEM;
880 scon = kzalloc(size + 1, GFP_KERNEL);
881 if (!scon)
882 goto out;
883
884 length = -ENOMEM;
885 tcon = kzalloc(size + 1, GFP_KERNEL);
886 if (!tcon)
887 goto out;
888
889 length = -ENOMEM;
890 namebuf = kzalloc(size + 1, GFP_KERNEL);
891 if (!namebuf)
892 goto out;
893
894 length = -EINVAL;
895 nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
896 if (nargs < 3 || nargs > 4)
897 goto out;
898 if (nargs == 4) {
899 /*
900 * If and when the name of new object to be queried contains
901 * either whitespace or multibyte characters, they shall be
902 * encoded based on the percentage-encoding rule.
903 * If not encoded, the sscanf logic picks up only left-half
904 * of the supplied name; splitted by a whitespace unexpectedly.
905 */
906 char *r, *w;
907 int c1, c2;
908
909 r = w = namebuf;
910 do {
911 c1 = *r++;
912 if (c1 == '+')
913 c1 = ' ';
914 else if (c1 == '%') {
915 c1 = hex_to_bin(*r++);
916 if (c1 < 0)
917 goto out;
918 c2 = hex_to_bin(*r++);
919 if (c2 < 0)
920 goto out;
921 c1 = (c1 << 4) | c2;
922 }
923 *w++ = c1;
924 } while (c1 != '\0');
925
926 objname = namebuf;
927 }
928
929 length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
930 if (length)
931 goto out;
932
933 length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
934 if (length)
935 goto out;
936
937 length = security_transition_sid_user(state, ssid, tsid, tclass,
938 objname, &newsid);
939 if (length)
940 goto out;
941
942 length = security_sid_to_context(state, newsid, &newcon, &len);
943 if (length)
944 goto out;
945
946 length = -ERANGE;
947 if (len > SIMPLE_TRANSACTION_LIMIT) {
948 pr_err("SELinux: %s: context size (%u) exceeds "
949 "payload max\n", __func__, len);
950 goto out;
951 }
952
953 memcpy(buf, newcon, len);
954 length = len;
955 out:
956 kfree(newcon);
957 kfree(namebuf);
958 kfree(tcon);
959 kfree(scon);
960 return length;
961 }
962
963 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
964 {
965 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
966 struct selinux_state *state = fsi->state;
967 char *scon = NULL, *tcon = NULL;
968 u32 ssid, tsid, newsid;
969 u16 tclass;
970 ssize_t length;
971 char *newcon = NULL;
972 u32 len;
973
974 length = avc_has_perm(&selinux_state,
975 current_sid(), SECINITSID_SECURITY,
976 SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
977 NULL);
978 if (length)
979 goto out;
980
981 length = -ENOMEM;
982 scon = kzalloc(size + 1, GFP_KERNEL);
983 if (!scon)
984 goto out;
985
986 length = -ENOMEM;
987 tcon = kzalloc(size + 1, GFP_KERNEL);
988 if (!tcon)
989 goto out;
990
991 length = -EINVAL;
992 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
993 goto out;
994
995 length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
996 if (length)
997 goto out;
998
999 length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1000 if (length)
1001 goto out;
1002
1003 length = security_change_sid(state, ssid, tsid, tclass, &newsid);
1004 if (length)
1005 goto out;
1006
1007 length = security_sid_to_context(state, newsid, &newcon, &len);
1008 if (length)
1009 goto out;
1010
1011 length = -ERANGE;
1012 if (len > SIMPLE_TRANSACTION_LIMIT)
1013 goto out;
1014
1015 memcpy(buf, newcon, len);
1016 length = len;
1017 out:
1018 kfree(newcon);
1019 kfree(tcon);
1020 kfree(scon);
1021 return length;
1022 }
1023
1024 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1025 {
1026 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1027 struct selinux_state *state = fsi->state;
1028 char *con = NULL, *user = NULL, *ptr;
1029 u32 sid, *sids = NULL;
1030 ssize_t length;
1031 char *newcon;
1032 int i, rc;
1033 u32 len, nsids;
1034
1035 length = avc_has_perm(&selinux_state,
1036 current_sid(), SECINITSID_SECURITY,
1037 SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1038 NULL);
1039 if (length)
1040 goto out;
1041
1042 length = -ENOMEM;
1043 con = kzalloc(size + 1, GFP_KERNEL);
1044 if (!con)
1045 goto out;
1046
1047 length = -ENOMEM;
1048 user = kzalloc(size + 1, GFP_KERNEL);
1049 if (!user)
1050 goto out;
1051
1052 length = -EINVAL;
1053 if (sscanf(buf, "%s %s", con, user) != 2)
1054 goto out;
1055
1056 length = security_context_str_to_sid(state, con, &sid, GFP_KERNEL);
1057 if (length)
1058 goto out;
1059
1060 length = security_get_user_sids(state, sid, user, &sids, &nsids);
1061 if (length)
1062 goto out;
1063
1064 length = sprintf(buf, "%u", nsids) + 1;
1065 ptr = buf + length;
1066 for (i = 0; i < nsids; i++) {
1067 rc = security_sid_to_context(state, sids[i], &newcon, &len);
1068 if (rc) {
1069 length = rc;
1070 goto out;
1071 }
1072 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1073 kfree(newcon);
1074 length = -ERANGE;
1075 goto out;
1076 }
1077 memcpy(ptr, newcon, len);
1078 kfree(newcon);
1079 ptr += len;
1080 length += len;
1081 }
1082 out:
1083 kfree(sids);
1084 kfree(user);
1085 kfree(con);
1086 return length;
1087 }
1088
1089 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1090 {
1091 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1092 struct selinux_state *state = fsi->state;
1093 char *scon = NULL, *tcon = NULL;
1094 u32 ssid, tsid, newsid;
1095 u16 tclass;
1096 ssize_t length;
1097 char *newcon = NULL;
1098 u32 len;
1099
1100 length = avc_has_perm(&selinux_state,
1101 current_sid(), SECINITSID_SECURITY,
1102 SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1103 NULL);
1104 if (length)
1105 goto out;
1106
1107 length = -ENOMEM;
1108 scon = kzalloc(size + 1, GFP_KERNEL);
1109 if (!scon)
1110 goto out;
1111
1112 length = -ENOMEM;
1113 tcon = kzalloc(size + 1, GFP_KERNEL);
1114 if (!tcon)
1115 goto out;
1116
1117 length = -EINVAL;
1118 if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1119 goto out;
1120
1121 length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1122 if (length)
1123 goto out;
1124
1125 length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1126 if (length)
1127 goto out;
1128
1129 length = security_member_sid(state, ssid, tsid, tclass, &newsid);
1130 if (length)
1131 goto out;
1132
1133 length = security_sid_to_context(state, newsid, &newcon, &len);
1134 if (length)
1135 goto out;
1136
1137 length = -ERANGE;
1138 if (len > SIMPLE_TRANSACTION_LIMIT) {
1139 pr_err("SELinux: %s: context size (%u) exceeds "
1140 "payload max\n", __func__, len);
1141 goto out;
1142 }
1143
1144 memcpy(buf, newcon, len);
1145 length = len;
1146 out:
1147 kfree(newcon);
1148 kfree(tcon);
1149 kfree(scon);
1150 return length;
1151 }
1152
1153 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1154 {
1155 struct inode *ret = new_inode(sb);
1156
1157 if (ret) {
1158 ret->i_mode = mode;
1159 ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret);
1160 }
1161 return ret;
1162 }
1163
1164 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1165 size_t count, loff_t *ppos)
1166 {
1167 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1168 char *page = NULL;
1169 ssize_t length;
1170 ssize_t ret;
1171 int cur_enforcing;
1172 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1173 const char *name = filep->f_path.dentry->d_name.name;
1174
1175 mutex_lock(&fsi->mutex);
1176
1177 ret = -EINVAL;
1178 if (index >= fsi->bool_num || strcmp(name,
1179 fsi->bool_pending_names[index]))
1180 goto out_unlock;
1181
1182 ret = -ENOMEM;
1183 page = (char *)get_zeroed_page(GFP_KERNEL);
1184 if (!page)
1185 goto out_unlock;
1186
1187 cur_enforcing = security_get_bool_value(fsi->state, index);
1188 if (cur_enforcing < 0) {
1189 ret = cur_enforcing;
1190 goto out_unlock;
1191 }
1192 length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1193 fsi->bool_pending_values[index]);
1194 mutex_unlock(&fsi->mutex);
1195 ret = simple_read_from_buffer(buf, count, ppos, page, length);
1196 out_free:
1197 free_page((unsigned long)page);
1198 return ret;
1199
1200 out_unlock:
1201 mutex_unlock(&fsi->mutex);
1202 goto out_free;
1203 }
1204
1205 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1206 size_t count, loff_t *ppos)
1207 {
1208 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1209 char *page = NULL;
1210 ssize_t length;
1211 int new_value;
1212 unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1213 const char *name = filep->f_path.dentry->d_name.name;
1214
1215 if (count >= PAGE_SIZE)
1216 return -ENOMEM;
1217
1218 /* No partial writes. */
1219 if (*ppos != 0)
1220 return -EINVAL;
1221
1222 page = memdup_user_nul(buf, count);
1223 if (IS_ERR(page))
1224 return PTR_ERR(page);
1225
1226 mutex_lock(&fsi->mutex);
1227
1228 length = avc_has_perm(&selinux_state,
1229 current_sid(), SECINITSID_SECURITY,
1230 SECCLASS_SECURITY, SECURITY__SETBOOL,
1231 NULL);
1232 if (length)
1233 goto out;
1234
1235 length = -EINVAL;
1236 if (index >= fsi->bool_num || strcmp(name,
1237 fsi->bool_pending_names[index]))
1238 goto out;
1239
1240 length = -EINVAL;
1241 if (sscanf(page, "%d", &new_value) != 1)
1242 goto out;
1243
1244 if (new_value)
1245 new_value = 1;
1246
1247 fsi->bool_pending_values[index] = new_value;
1248 length = count;
1249
1250 out:
1251 mutex_unlock(&fsi->mutex);
1252 kfree(page);
1253 return length;
1254 }
1255
1256 static const struct file_operations sel_bool_ops = {
1257 .read = sel_read_bool,
1258 .write = sel_write_bool,
1259 .llseek = generic_file_llseek,
1260 };
1261
1262 static ssize_t sel_commit_bools_write(struct file *filep,
1263 const char __user *buf,
1264 size_t count, loff_t *ppos)
1265 {
1266 struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1267 char *page = NULL;
1268 ssize_t length;
1269 int new_value;
1270
1271 if (count >= PAGE_SIZE)
1272 return -ENOMEM;
1273
1274 /* No partial writes. */
1275 if (*ppos != 0)
1276 return -EINVAL;
1277
1278 page = memdup_user_nul(buf, count);
1279 if (IS_ERR(page))
1280 return PTR_ERR(page);
1281
1282 mutex_lock(&fsi->mutex);
1283
1284 length = avc_has_perm(&selinux_state,
1285 current_sid(), SECINITSID_SECURITY,
1286 SECCLASS_SECURITY, SECURITY__SETBOOL,
1287 NULL);
1288 if (length)
1289 goto out;
1290
1291 length = -EINVAL;
1292 if (sscanf(page, "%d", &new_value) != 1)
1293 goto out;
1294
1295 length = 0;
1296 if (new_value && fsi->bool_pending_values)
1297 length = security_set_bools(fsi->state, fsi->bool_num,
1298 fsi->bool_pending_values);
1299
1300 if (!length)
1301 length = count;
1302
1303 out:
1304 mutex_unlock(&fsi->mutex);
1305 kfree(page);
1306 return length;
1307 }
1308
1309 static const struct file_operations sel_commit_bools_ops = {
1310 .write = sel_commit_bools_write,
1311 .llseek = generic_file_llseek,
1312 };
1313
1314 static void sel_remove_entries(struct dentry *de)
1315 {
1316 d_genocide(de);
1317 shrink_dcache_parent(de);
1318 }
1319
1320 #define BOOL_DIR_NAME "booleans"
1321
1322 static int sel_make_bools(struct selinux_fs_info *fsi)
1323 {
1324 int i, ret;
1325 ssize_t len;
1326 struct dentry *dentry = NULL;
1327 struct dentry *dir = fsi->bool_dir;
1328 struct inode *inode = NULL;
1329 struct inode_security_struct *isec;
1330 char **names = NULL, *page;
1331 int num;
1332 int *values = NULL;
1333 u32 sid;
1334
1335 /* remove any existing files */
1336 for (i = 0; i < fsi->bool_num; i++)
1337 kfree(fsi->bool_pending_names[i]);
1338 kfree(fsi->bool_pending_names);
1339 kfree(fsi->bool_pending_values);
1340 fsi->bool_num = 0;
1341 fsi->bool_pending_names = NULL;
1342 fsi->bool_pending_values = NULL;
1343
1344 sel_remove_entries(dir);
1345
1346 ret = -ENOMEM;
1347 page = (char *)get_zeroed_page(GFP_KERNEL);
1348 if (!page)
1349 goto out;
1350
1351 ret = security_get_bools(fsi->state, &num, &names, &values);
1352 if (ret)
1353 goto out;
1354
1355 for (i = 0; i < num; i++) {
1356 ret = -ENOMEM;
1357 dentry = d_alloc_name(dir, names[i]);
1358 if (!dentry)
1359 goto out;
1360
1361 ret = -ENOMEM;
1362 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1363 if (!inode) {
1364 dput(dentry);
1365 goto out;
1366 }
1367
1368 ret = -ENAMETOOLONG;
1369 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1370 if (len >= PAGE_SIZE) {
1371 dput(dentry);
1372 iput(inode);
1373 goto out;
1374 }
1375
1376 isec = selinux_inode(inode);
1377 ret = security_genfs_sid(fsi->state, "selinuxfs", page,
1378 SECCLASS_FILE, &sid);
1379 if (ret) {
1380 pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1381 page);
1382 sid = SECINITSID_SECURITY;
1383 }
1384
1385 isec->sid = sid;
1386 isec->initialized = LABEL_INITIALIZED;
1387 inode->i_fop = &sel_bool_ops;
1388 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1389 d_add(dentry, inode);
1390 }
1391 fsi->bool_num = num;
1392 fsi->bool_pending_names = names;
1393 fsi->bool_pending_values = values;
1394
1395 free_page((unsigned long)page);
1396 return 0;
1397 out:
1398 free_page((unsigned long)page);
1399
1400 if (names) {
1401 for (i = 0; i < num; i++)
1402 kfree(names[i]);
1403 kfree(names);
1404 }
1405 kfree(values);
1406 sel_remove_entries(dir);
1407
1408 return ret;
1409 }
1410
1411 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1412 size_t count, loff_t *ppos)
1413 {
1414 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1415 struct selinux_state *state = fsi->state;
1416 char tmpbuf[TMPBUFLEN];
1417 ssize_t length;
1418
1419 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1420 avc_get_cache_threshold(state->avc));
1421 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1422 }
1423
1424 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1425 const char __user *buf,
1426 size_t count, loff_t *ppos)
1427
1428 {
1429 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1430 struct selinux_state *state = fsi->state;
1431 char *page;
1432 ssize_t ret;
1433 unsigned int new_value;
1434
1435 ret = avc_has_perm(&selinux_state,
1436 current_sid(), SECINITSID_SECURITY,
1437 SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1438 NULL);
1439 if (ret)
1440 return ret;
1441
1442 if (count >= PAGE_SIZE)
1443 return -ENOMEM;
1444
1445 /* No partial writes. */
1446 if (*ppos != 0)
1447 return -EINVAL;
1448
1449 page = memdup_user_nul(buf, count);
1450 if (IS_ERR(page))
1451 return PTR_ERR(page);
1452
1453 ret = -EINVAL;
1454 if (sscanf(page, "%u", &new_value) != 1)
1455 goto out;
1456
1457 avc_set_cache_threshold(state->avc, new_value);
1458
1459 ret = count;
1460 out:
1461 kfree(page);
1462 return ret;
1463 }
1464
1465 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1466 size_t count, loff_t *ppos)
1467 {
1468 struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1469 struct selinux_state *state = fsi->state;
1470 char *page;
1471 ssize_t length;
1472
1473 page = (char *)__get_free_page(GFP_KERNEL);
1474 if (!page)
1475 return -ENOMEM;
1476
1477 length = avc_get_hash_stats(state->avc, page);
1478 if (length >= 0)
1479 length = simple_read_from_buffer(buf, count, ppos, page, length);
1480 free_page((unsigned long)page);
1481
1482 return length;
1483 }
1484
1485 static const struct file_operations sel_avc_cache_threshold_ops = {
1486 .read = sel_read_avc_cache_threshold,
1487 .write = sel_write_avc_cache_threshold,
1488 .llseek = generic_file_llseek,
1489 };
1490
1491 static const struct file_operations sel_avc_hash_stats_ops = {
1492 .read = sel_read_avc_hash_stats,
1493 .llseek = generic_file_llseek,
1494 };
1495
1496 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1497 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1498 {
1499 int cpu;
1500
1501 for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1502 if (!cpu_possible(cpu))
1503 continue;
1504 *idx = cpu + 1;
1505 return &per_cpu(avc_cache_stats, cpu);
1506 }
1507 return NULL;
1508 }
1509
1510 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1511 {
1512 loff_t n = *pos - 1;
1513
1514 if (*pos == 0)
1515 return SEQ_START_TOKEN;
1516
1517 return sel_avc_get_stat_idx(&n);
1518 }
1519
1520 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1521 {
1522 return sel_avc_get_stat_idx(pos);
1523 }
1524
1525 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1526 {
1527 struct avc_cache_stats *st = v;
1528
1529 if (v == SEQ_START_TOKEN) {
1530 seq_puts(seq,
1531 "lookups hits misses allocations reclaims frees\n");
1532 } else {
1533 unsigned int lookups = st->lookups;
1534 unsigned int misses = st->misses;
1535 unsigned int hits = lookups - misses;
1536 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1537 hits, misses, st->allocations,
1538 st->reclaims, st->frees);
1539 }
1540 return 0;
1541 }
1542
1543 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1544 { }
1545
1546 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1547 .start = sel_avc_stats_seq_start,
1548 .next = sel_avc_stats_seq_next,
1549 .show = sel_avc_stats_seq_show,
1550 .stop = sel_avc_stats_seq_stop,
1551 };
1552
1553 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1554 {
1555 return seq_open(file, &sel_avc_cache_stats_seq_ops);
1556 }
1557
1558 static const struct file_operations sel_avc_cache_stats_ops = {
1559 .open = sel_open_avc_cache_stats,
1560 .read = seq_read,
1561 .llseek = seq_lseek,
1562 .release = seq_release,
1563 };
1564 #endif
1565
1566 static int sel_make_avc_files(struct dentry *dir)
1567 {
1568 struct super_block *sb = dir->d_sb;
1569 struct selinux_fs_info *fsi = sb->s_fs_info;
1570 int i;
1571 static const struct tree_descr files[] = {
1572 { "cache_threshold",
1573 &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1574 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1575 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1576 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1577 #endif
1578 };
1579
1580 for (i = 0; i < ARRAY_SIZE(files); i++) {
1581 struct inode *inode;
1582 struct dentry *dentry;
1583
1584 dentry = d_alloc_name(dir, files[i].name);
1585 if (!dentry)
1586 return -ENOMEM;
1587
1588 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1589 if (!inode) {
1590 dput(dentry);
1591 return -ENOMEM;
1592 }
1593
1594 inode->i_fop = files[i].ops;
1595 inode->i_ino = ++fsi->last_ino;
1596 d_add(dentry, inode);
1597 }
1598
1599 return 0;
1600 }
1601
1602 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1603 size_t count, loff_t *ppos)
1604 {
1605 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1606 char *con;
1607 u32 sid, len;
1608 ssize_t ret;
1609
1610 sid = file_inode(file)->i_ino&SEL_INO_MASK;
1611 ret = security_sid_to_context(fsi->state, sid, &con, &len);
1612 if (ret)
1613 return ret;
1614
1615 ret = simple_read_from_buffer(buf, count, ppos, con, len);
1616 kfree(con);
1617 return ret;
1618 }
1619
1620 static const struct file_operations sel_initcon_ops = {
1621 .read = sel_read_initcon,
1622 .llseek = generic_file_llseek,
1623 };
1624
1625 static int sel_make_initcon_files(struct dentry *dir)
1626 {
1627 int i;
1628
1629 for (i = 1; i <= SECINITSID_NUM; i++) {
1630 struct inode *inode;
1631 struct dentry *dentry;
1632 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1633 if (!dentry)
1634 return -ENOMEM;
1635
1636 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1637 if (!inode) {
1638 dput(dentry);
1639 return -ENOMEM;
1640 }
1641
1642 inode->i_fop = &sel_initcon_ops;
1643 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1644 d_add(dentry, inode);
1645 }
1646
1647 return 0;
1648 }
1649
1650 static inline unsigned long sel_class_to_ino(u16 class)
1651 {
1652 return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1653 }
1654
1655 static inline u16 sel_ino_to_class(unsigned long ino)
1656 {
1657 return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1658 }
1659
1660 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1661 {
1662 return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1663 }
1664
1665 static inline u32 sel_ino_to_perm(unsigned long ino)
1666 {
1667 return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1668 }
1669
1670 static ssize_t sel_read_class(struct file *file, char __user *buf,
1671 size_t count, loff_t *ppos)
1672 {
1673 unsigned long ino = file_inode(file)->i_ino;
1674 char res[TMPBUFLEN];
1675 ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1676 return simple_read_from_buffer(buf, count, ppos, res, len);
1677 }
1678
1679 static const struct file_operations sel_class_ops = {
1680 .read = sel_read_class,
1681 .llseek = generic_file_llseek,
1682 };
1683
1684 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1685 size_t count, loff_t *ppos)
1686 {
1687 unsigned long ino = file_inode(file)->i_ino;
1688 char res[TMPBUFLEN];
1689 ssize_t len = snprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1690 return simple_read_from_buffer(buf, count, ppos, res, len);
1691 }
1692
1693 static const struct file_operations sel_perm_ops = {
1694 .read = sel_read_perm,
1695 .llseek = generic_file_llseek,
1696 };
1697
1698 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1699 size_t count, loff_t *ppos)
1700 {
1701 struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1702 int value;
1703 char tmpbuf[TMPBUFLEN];
1704 ssize_t length;
1705 unsigned long i_ino = file_inode(file)->i_ino;
1706
1707 value = security_policycap_supported(fsi->state, i_ino & SEL_INO_MASK);
1708 length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1709
1710 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1711 }
1712
1713 static const struct file_operations sel_policycap_ops = {
1714 .read = sel_read_policycap,
1715 .llseek = generic_file_llseek,
1716 };
1717
1718 static int sel_make_perm_files(char *objclass, int classvalue,
1719 struct dentry *dir)
1720 {
1721 struct selinux_fs_info *fsi = dir->d_sb->s_fs_info;
1722 int i, rc, nperms;
1723 char **perms;
1724
1725 rc = security_get_permissions(fsi->state, objclass, &perms, &nperms);
1726 if (rc)
1727 return rc;
1728
1729 for (i = 0; i < nperms; i++) {
1730 struct inode *inode;
1731 struct dentry *dentry;
1732
1733 rc = -ENOMEM;
1734 dentry = d_alloc_name(dir, perms[i]);
1735 if (!dentry)
1736 goto out;
1737
1738 rc = -ENOMEM;
1739 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1740 if (!inode) {
1741 dput(dentry);
1742 goto out;
1743 }
1744
1745 inode->i_fop = &sel_perm_ops;
1746 /* i+1 since perm values are 1-indexed */
1747 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1748 d_add(dentry, inode);
1749 }
1750 rc = 0;
1751 out:
1752 for (i = 0; i < nperms; i++)
1753 kfree(perms[i]);
1754 kfree(perms);
1755 return rc;
1756 }
1757
1758 static int sel_make_class_dir_entries(char *classname, int index,
1759 struct dentry *dir)
1760 {
1761 struct super_block *sb = dir->d_sb;
1762 struct selinux_fs_info *fsi = sb->s_fs_info;
1763 struct dentry *dentry = NULL;
1764 struct inode *inode = NULL;
1765 int rc;
1766
1767 dentry = d_alloc_name(dir, "index");
1768 if (!dentry)
1769 return -ENOMEM;
1770
1771 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1772 if (!inode) {
1773 dput(dentry);
1774 return -ENOMEM;
1775 }
1776
1777 inode->i_fop = &sel_class_ops;
1778 inode->i_ino = sel_class_to_ino(index);
1779 d_add(dentry, inode);
1780
1781 dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
1782 if (IS_ERR(dentry))
1783 return PTR_ERR(dentry);
1784
1785 rc = sel_make_perm_files(classname, index, dentry);
1786
1787 return rc;
1788 }
1789
1790 static int sel_make_classes(struct selinux_fs_info *fsi)
1791 {
1792
1793 int rc, nclasses, i;
1794 char **classes;
1795
1796 /* delete any existing entries */
1797 sel_remove_entries(fsi->class_dir);
1798
1799 rc = security_get_classes(fsi->state, &classes, &nclasses);
1800 if (rc)
1801 return rc;
1802
1803 /* +2 since classes are 1-indexed */
1804 fsi->last_class_ino = sel_class_to_ino(nclasses + 2);
1805
1806 for (i = 0; i < nclasses; i++) {
1807 struct dentry *class_name_dir;
1808
1809 class_name_dir = sel_make_dir(fsi->class_dir, classes[i],
1810 &fsi->last_class_ino);
1811 if (IS_ERR(class_name_dir)) {
1812 rc = PTR_ERR(class_name_dir);
1813 goto out;
1814 }
1815
1816 /* i+1 since class values are 1-indexed */
1817 rc = sel_make_class_dir_entries(classes[i], i + 1,
1818 class_name_dir);
1819 if (rc)
1820 goto out;
1821 }
1822 rc = 0;
1823 out:
1824 for (i = 0; i < nclasses; i++)
1825 kfree(classes[i]);
1826 kfree(classes);
1827 return rc;
1828 }
1829
1830 static int sel_make_policycap(struct selinux_fs_info *fsi)
1831 {
1832 unsigned int iter;
1833 struct dentry *dentry = NULL;
1834 struct inode *inode = NULL;
1835
1836 sel_remove_entries(fsi->policycap_dir);
1837
1838 for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1839 if (iter < ARRAY_SIZE(selinux_policycap_names))
1840 dentry = d_alloc_name(fsi->policycap_dir,
1841 selinux_policycap_names[iter]);
1842 else
1843 dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1844
1845 if (dentry == NULL)
1846 return -ENOMEM;
1847
1848 inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1849 if (inode == NULL) {
1850 dput(dentry);
1851 return -ENOMEM;
1852 }
1853
1854 inode->i_fop = &sel_policycap_ops;
1855 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1856 d_add(dentry, inode);
1857 }
1858
1859 return 0;
1860 }
1861
1862 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1863 unsigned long *ino)
1864 {
1865 struct dentry *dentry = d_alloc_name(dir, name);
1866 struct inode *inode;
1867
1868 if (!dentry)
1869 return ERR_PTR(-ENOMEM);
1870
1871 inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1872 if (!inode) {
1873 dput(dentry);
1874 return ERR_PTR(-ENOMEM);
1875 }
1876
1877 inode->i_op = &simple_dir_inode_operations;
1878 inode->i_fop = &simple_dir_operations;
1879 inode->i_ino = ++(*ino);
1880 /* directory inodes start off with i_nlink == 2 (for "." entry) */
1881 inc_nlink(inode);
1882 d_add(dentry, inode);
1883 /* bump link count on parent directory, too */
1884 inc_nlink(d_inode(dir));
1885
1886 return dentry;
1887 }
1888
1889 #define NULL_FILE_NAME "null"
1890
1891 static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
1892 {
1893 struct selinux_fs_info *fsi;
1894 int ret;
1895 struct dentry *dentry;
1896 struct inode *inode;
1897 struct inode_security_struct *isec;
1898
1899 static const struct tree_descr selinux_files[] = {
1900 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1901 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1902 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1903 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1904 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1905 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1906 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1907 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1908 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1909 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1910 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1911 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1912 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1913 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1914 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1915 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1916 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
1917 [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
1918 S_IWUGO},
1919 /* last one */ {""}
1920 };
1921
1922 ret = selinux_fs_info_create(sb);
1923 if (ret)
1924 goto err;
1925
1926 ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1927 if (ret)
1928 goto err;
1929
1930 fsi = sb->s_fs_info;
1931 fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
1932 if (IS_ERR(fsi->bool_dir)) {
1933 ret = PTR_ERR(fsi->bool_dir);
1934 fsi->bool_dir = NULL;
1935 goto err;
1936 }
1937
1938 ret = -ENOMEM;
1939 dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1940 if (!dentry)
1941 goto err;
1942
1943 ret = -ENOMEM;
1944 inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1945 if (!inode) {
1946 dput(dentry);
1947 goto err;
1948 }
1949
1950 inode->i_ino = ++fsi->last_ino;
1951 isec = selinux_inode(inode);
1952 isec->sid = SECINITSID_DEVNULL;
1953 isec->sclass = SECCLASS_CHR_FILE;
1954 isec->initialized = LABEL_INITIALIZED;
1955
1956 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1957 d_add(dentry, inode);
1958
1959 dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
1960 if (IS_ERR(dentry)) {
1961 ret = PTR_ERR(dentry);
1962 goto err;
1963 }
1964
1965 ret = sel_make_avc_files(dentry);
1966 if (ret)
1967 goto err;
1968
1969 dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
1970 if (IS_ERR(dentry)) {
1971 ret = PTR_ERR(dentry);
1972 goto err;
1973 }
1974
1975 ret = sel_make_initcon_files(dentry);
1976 if (ret)
1977 goto err;
1978
1979 fsi->class_dir = sel_make_dir(sb->s_root, "class", &fsi->last_ino);
1980 if (IS_ERR(fsi->class_dir)) {
1981 ret = PTR_ERR(fsi->class_dir);
1982 fsi->class_dir = NULL;
1983 goto err;
1984 }
1985
1986 fsi->policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities",
1987 &fsi->last_ino);
1988 if (IS_ERR(fsi->policycap_dir)) {
1989 ret = PTR_ERR(fsi->policycap_dir);
1990 fsi->policycap_dir = NULL;
1991 goto err;
1992 }
1993
1994 ret = sel_make_policy_nodes(fsi);
1995 if (ret)
1996 goto err;
1997 return 0;
1998 err:
1999 pr_err("SELinux: %s: failed while creating inodes\n",
2000 __func__);
2001
2002 selinux_fs_info_free(sb);
2003
2004 return ret;
2005 }
2006
2007 static int sel_get_tree(struct fs_context *fc)
2008 {
2009 return get_tree_single(fc, sel_fill_super);
2010 }
2011
2012 static const struct fs_context_operations sel_context_ops = {
2013 .get_tree = sel_get_tree,
2014 };
2015
2016 static int sel_init_fs_context(struct fs_context *fc)
2017 {
2018 fc->ops = &sel_context_ops;
2019 return 0;
2020 }
2021
2022 static void sel_kill_sb(struct super_block *sb)
2023 {
2024 selinux_fs_info_free(sb);
2025 kill_litter_super(sb);
2026 }
2027
2028 static struct file_system_type sel_fs_type = {
2029 .name = "selinuxfs",
2030 .init_fs_context = sel_init_fs_context,
2031 .kill_sb = sel_kill_sb,
2032 };
2033
2034 struct vfsmount *selinuxfs_mount;
2035 struct path selinux_null;
2036
2037 static int __init init_sel_fs(void)
2038 {
2039 struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2040 sizeof(NULL_FILE_NAME)-1);
2041 int err;
2042
2043 if (!selinux_enabled)
2044 return 0;
2045
2046 err = sysfs_create_mount_point(fs_kobj, "selinux");
2047 if (err)
2048 return err;
2049
2050 err = register_filesystem(&sel_fs_type);
2051 if (err) {
2052 sysfs_remove_mount_point(fs_kobj, "selinux");
2053 return err;
2054 }
2055
2056 selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
2057 if (IS_ERR(selinuxfs_mount)) {
2058 pr_err("selinuxfs: could not mount!\n");
2059 err = PTR_ERR(selinuxfs_mount);
2060 selinuxfs_mount = NULL;
2061 }
2062 selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2063 &null_name);
2064 if (IS_ERR(selinux_null.dentry)) {
2065 pr_err("selinuxfs: could not lookup null!\n");
2066 err = PTR_ERR(selinux_null.dentry);
2067 selinux_null.dentry = NULL;
2068 }
2069
2070 return err;
2071 }
2072
2073 __initcall(init_sel_fs);
2074
2075 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
2076 void exit_sel_fs(void)
2077 {
2078 sysfs_remove_mount_point(fs_kobj, "selinux");
2079 dput(selinux_null.dentry);
2080 kern_unmount(selinuxfs_mount);
2081 unregister_filesystem(&sel_fs_type);
2082 }
2083 #endif
connection oriented routing