[PATCH] MLSXFRM: fix mis-labelling of child sockets
[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/kernel.h>
13 #include <linux/pagemap.h>
14 #include <linux/slab.h>
15 #include <linux/vmalloc.h>
16 #include <linux/fs.h>
17 #include <linux/mutex.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 <linux/audit.h>
25 #include <asm/uaccess.h>
26 #include <asm/semaphore.h>
27
28 /* selinuxfs pseudo filesystem for exporting the security policy API.
29    Based on the proc code and the fs/nfsd/nfsctl.c code. */
30
31 #include "flask.h"
32 #include "avc.h"
33 #include "avc_ss.h"
34 #include "security.h"
35 #include "objsec.h"
36 #include "conditional.h"
37
38 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
39
40 #ifdef CONFIG_SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT
41 #define SELINUX_COMPAT_NET_VALUE 0
42 #else
43 #define SELINUX_COMPAT_NET_VALUE 1
44 #endif
45
46 int selinux_compat_net = SELINUX_COMPAT_NET_VALUE;
47
48 static int __init checkreqprot_setup(char *str)
49 {
50         selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0;
51         return 1;
52 }
53 __setup("checkreqprot=", checkreqprot_setup);
54
55 static int __init selinux_compat_net_setup(char *str)
56 {
57         selinux_compat_net = simple_strtoul(str,NULL,0) ? 1 : 0;
58         return 1;
59 }
60 __setup("selinux_compat_net=", selinux_compat_net_setup);
61
62
63 static DEFINE_MUTEX(sel_mutex);
64
65 /* global data for booleans */
66 static struct dentry *bool_dir = NULL;
67 static int bool_num = 0;
68 static int *bool_pending_values = NULL;
69
70 extern void selnl_notify_setenforce(int val);
71
72 /* Check whether a task is allowed to use a security operation. */
73 static int task_has_security(struct task_struct *tsk,
74                              u32 perms)
75 {
76         struct task_security_struct *tsec;
77
78         tsec = tsk->security;
79         if (!tsec)
80                 return -EACCES;
81
82         return avc_has_perm(tsec->sid, SECINITSID_SECURITY,
83                             SECCLASS_SECURITY, perms, NULL);
84 }
85
86 enum sel_inos {
87         SEL_ROOT_INO = 2,
88         SEL_LOAD,       /* load policy */
89         SEL_ENFORCE,    /* get or set enforcing status */
90         SEL_CONTEXT,    /* validate context */
91         SEL_ACCESS,     /* compute access decision */
92         SEL_CREATE,     /* compute create labeling decision */
93         SEL_RELABEL,    /* compute relabeling decision */
94         SEL_USER,       /* compute reachable user contexts */
95         SEL_POLICYVERS, /* return policy version for this kernel */
96         SEL_COMMIT_BOOLS, /* commit new boolean values */
97         SEL_MLS,        /* return if MLS policy is enabled */
98         SEL_DISABLE,    /* disable SELinux until next reboot */
99         SEL_AVC,        /* AVC management directory */
100         SEL_MEMBER,     /* compute polyinstantiation membership decision */
101         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
102         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
103 };
104
105 #define TMPBUFLEN       12
106 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
107                                 size_t count, loff_t *ppos)
108 {
109         char tmpbuf[TMPBUFLEN];
110         ssize_t length;
111
112         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
113         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
114 }
115
116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
117 static ssize_t sel_write_enforce(struct file * file, const char __user * buf,
118                                  size_t count, loff_t *ppos)
119
120 {
121         char *page;
122         ssize_t length;
123         int new_value;
124
125         if (count >= PAGE_SIZE)
126                 return -ENOMEM;
127         if (*ppos != 0) {
128                 /* No partial writes. */
129                 return -EINVAL;
130         }
131         page = (char*)get_zeroed_page(GFP_KERNEL);
132         if (!page)
133                 return -ENOMEM;
134         length = -EFAULT;
135         if (copy_from_user(page, buf, count))
136                 goto out;
137
138         length = -EINVAL;
139         if (sscanf(page, "%d", &new_value) != 1)
140                 goto out;
141
142         if (new_value != selinux_enforcing) {
143                 length = task_has_security(current, SECURITY__SETENFORCE);
144                 if (length)
145                         goto out;
146                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
147                         "enforcing=%d old_enforcing=%d auid=%u", new_value, 
148                         selinux_enforcing,
149                         audit_get_loginuid(current->audit_context));
150                 selinux_enforcing = new_value;
151                 if (selinux_enforcing)
152                         avc_ss_reset(0);
153                 selnl_notify_setenforce(selinux_enforcing);
154         }
155         length = count;
156 out:
157         free_page((unsigned long) page);
158         return length;
159 }
160 #else
161 #define sel_write_enforce NULL
162 #endif
163
164 static struct file_operations sel_enforce_ops = {
165         .read           = sel_read_enforce,
166         .write          = sel_write_enforce,
167 };
168
169 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
170 static ssize_t sel_write_disable(struct file * file, const char __user * buf,
171                                  size_t count, loff_t *ppos)
172
173 {
174         char *page;
175         ssize_t length;
176         int new_value;
177         extern int selinux_disable(void);
178
179         if (count >= PAGE_SIZE)
180                 return -ENOMEM;
181         if (*ppos != 0) {
182                 /* No partial writes. */
183                 return -EINVAL;
184         }
185         page = (char*)get_zeroed_page(GFP_KERNEL);
186         if (!page)
187                 return -ENOMEM;
188         length = -EFAULT;
189         if (copy_from_user(page, buf, count))
190                 goto out;
191
192         length = -EINVAL;
193         if (sscanf(page, "%d", &new_value) != 1)
194                 goto out;
195
196         if (new_value) {
197                 length = selinux_disable();
198                 if (length < 0)
199                         goto out;
200                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
201                         "selinux=0 auid=%u",
202                         audit_get_loginuid(current->audit_context));
203         }
204
205         length = count;
206 out:
207         free_page((unsigned long) page);
208         return length;
209 }
210 #else
211 #define sel_write_disable NULL
212 #endif
213
214 static struct file_operations sel_disable_ops = {
215         .write          = sel_write_disable,
216 };
217
218 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
219                                    size_t count, loff_t *ppos)
220 {
221         char tmpbuf[TMPBUFLEN];
222         ssize_t length;
223
224         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
225         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
226 }
227
228 static struct file_operations sel_policyvers_ops = {
229         .read           = sel_read_policyvers,
230 };
231
232 /* declaration for sel_write_load */
233 static int sel_make_bools(void);
234
235 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
236                                 size_t count, loff_t *ppos)
237 {
238         char tmpbuf[TMPBUFLEN];
239         ssize_t length;
240
241         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
242         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
243 }
244
245 static struct file_operations sel_mls_ops = {
246         .read           = sel_read_mls,
247 };
248
249 static ssize_t sel_write_load(struct file * file, const char __user * buf,
250                               size_t count, loff_t *ppos)
251
252 {
253         int ret;
254         ssize_t length;
255         void *data = NULL;
256
257         mutex_lock(&sel_mutex);
258
259         length = task_has_security(current, SECURITY__LOAD_POLICY);
260         if (length)
261                 goto out;
262
263         if (*ppos != 0) {
264                 /* No partial writes. */
265                 length = -EINVAL;
266                 goto out;
267         }
268
269         if ((count > 64 * 1024 * 1024)
270             || (data = vmalloc(count)) == NULL) {
271                 length = -ENOMEM;
272                 goto out;
273         }
274
275         length = -EFAULT;
276         if (copy_from_user(data, buf, count) != 0)
277                 goto out;
278
279         length = security_load_policy(data, count);
280         if (length)
281                 goto out;
282
283         ret = sel_make_bools();
284         if (ret)
285                 length = ret;
286         else
287                 length = count;
288         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
289                 "policy loaded auid=%u",
290                 audit_get_loginuid(current->audit_context));
291 out:
292         mutex_unlock(&sel_mutex);
293         vfree(data);
294         return length;
295 }
296
297 static struct file_operations sel_load_ops = {
298         .write          = sel_write_load,
299 };
300
301 static ssize_t sel_write_context(struct file * file, char *buf, size_t size)
302 {
303         char *canon;
304         u32 sid, len;
305         ssize_t length;
306
307         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
308         if (length)
309                 return length;
310
311         length = security_context_to_sid(buf, size, &sid);
312         if (length < 0)
313                 return length;
314
315         length = security_sid_to_context(sid, &canon, &len);
316         if (length < 0)
317                 return length;
318
319         if (len > SIMPLE_TRANSACTION_LIMIT) {
320                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
321                        "max\n", __FUNCTION__, len);
322                 length = -ERANGE;
323                 goto out;
324         }
325
326         memcpy(buf, canon, len);
327         length = len;
328 out:
329         kfree(canon);
330         return length;
331 }
332
333 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
334                                      size_t count, loff_t *ppos)
335 {
336         char tmpbuf[TMPBUFLEN];
337         ssize_t length;
338
339         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
340         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
341 }
342
343 static ssize_t sel_write_checkreqprot(struct file * file, const char __user * buf,
344                                       size_t count, loff_t *ppos)
345 {
346         char *page;
347         ssize_t length;
348         unsigned int new_value;
349
350         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
351         if (length)
352                 return length;
353
354         if (count >= PAGE_SIZE)
355                 return -ENOMEM;
356         if (*ppos != 0) {
357                 /* No partial writes. */
358                 return -EINVAL;
359         }
360         page = (char*)get_zeroed_page(GFP_KERNEL);
361         if (!page)
362                 return -ENOMEM;
363         length = -EFAULT;
364         if (copy_from_user(page, buf, count))
365                 goto out;
366
367         length = -EINVAL;
368         if (sscanf(page, "%u", &new_value) != 1)
369                 goto out;
370
371         selinux_checkreqprot = new_value ? 1 : 0;
372         length = count;
373 out:
374         free_page((unsigned long) page);
375         return length;
376 }
377 static struct file_operations sel_checkreqprot_ops = {
378         .read           = sel_read_checkreqprot,
379         .write          = sel_write_checkreqprot,
380 };
381
382 static ssize_t sel_read_compat_net(struct file *filp, char __user *buf,
383                                    size_t count, loff_t *ppos)
384 {
385         char tmpbuf[TMPBUFLEN];
386         ssize_t length;
387
388         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_compat_net);
389         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
390 }
391
392 static ssize_t sel_write_compat_net(struct file * file, const char __user * buf,
393                                     size_t count, loff_t *ppos)
394 {
395         char *page;
396         ssize_t length;
397         int new_value;
398
399         length = task_has_security(current, SECURITY__LOAD_POLICY);
400         if (length)
401                 return length;
402
403         if (count >= PAGE_SIZE)
404                 return -ENOMEM;
405         if (*ppos != 0) {
406                 /* No partial writes. */
407                 return -EINVAL;
408         }
409         page = (char*)get_zeroed_page(GFP_KERNEL);
410         if (!page)
411                 return -ENOMEM;
412         length = -EFAULT;
413         if (copy_from_user(page, buf, count))
414                 goto out;
415
416         length = -EINVAL;
417         if (sscanf(page, "%d", &new_value) != 1)
418                 goto out;
419
420         selinux_compat_net = new_value ? 1 : 0;
421         length = count;
422 out:
423         free_page((unsigned long) page);
424         return length;
425 }
426 static struct file_operations sel_compat_net_ops = {
427         .read           = sel_read_compat_net,
428         .write          = sel_write_compat_net,
429 };
430
431 /*
432  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
433  */
434 static ssize_t sel_write_access(struct file * file, char *buf, size_t size);
435 static ssize_t sel_write_create(struct file * file, char *buf, size_t size);
436 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size);
437 static ssize_t sel_write_user(struct file * file, char *buf, size_t size);
438 static ssize_t sel_write_member(struct file * file, char *buf, size_t size);
439
440 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
441         [SEL_ACCESS] = sel_write_access,
442         [SEL_CREATE] = sel_write_create,
443         [SEL_RELABEL] = sel_write_relabel,
444         [SEL_USER] = sel_write_user,
445         [SEL_MEMBER] = sel_write_member,
446         [SEL_CONTEXT] = sel_write_context,
447 };
448
449 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
450 {
451         ino_t ino =  file->f_dentry->d_inode->i_ino;
452         char *data;
453         ssize_t rv;
454
455         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
456                 return -EINVAL;
457
458         data = simple_transaction_get(file, buf, size);
459         if (IS_ERR(data))
460                 return PTR_ERR(data);
461
462         rv =  write_op[ino](file, data, size);
463         if (rv>0) {
464                 simple_transaction_set(file, rv);
465                 rv = size;
466         }
467         return rv;
468 }
469
470 static struct file_operations transaction_ops = {
471         .write          = selinux_transaction_write,
472         .read           = simple_transaction_read,
473         .release        = simple_transaction_release,
474 };
475
476 /*
477  * payload - write methods
478  * If the method has a response, the response should be put in buf,
479  * and the length returned.  Otherwise return 0 or and -error.
480  */
481
482 static ssize_t sel_write_access(struct file * file, char *buf, size_t size)
483 {
484         char *scon, *tcon;
485         u32 ssid, tsid;
486         u16 tclass;
487         u32 req;
488         struct av_decision avd;
489         ssize_t length;
490
491         length = task_has_security(current, SECURITY__COMPUTE_AV);
492         if (length)
493                 return length;
494
495         length = -ENOMEM;
496         scon = kzalloc(size+1, GFP_KERNEL);
497         if (!scon)
498                 return length;
499
500         tcon = kzalloc(size+1, GFP_KERNEL);
501         if (!tcon)
502                 goto out;
503
504         length = -EINVAL;
505         if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
506                 goto out2;
507
508         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
509         if (length < 0)
510                 goto out2;
511         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
512         if (length < 0)
513                 goto out2;
514
515         length = security_compute_av(ssid, tsid, tclass, req, &avd);
516         if (length < 0)
517                 goto out2;
518
519         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
520                           "%x %x %x %x %u",
521                           avd.allowed, avd.decided,
522                           avd.auditallow, avd.auditdeny,
523                           avd.seqno);
524 out2:
525         kfree(tcon);
526 out:
527         kfree(scon);
528         return length;
529 }
530
531 static ssize_t sel_write_create(struct file * file, char *buf, size_t size)
532 {
533         char *scon, *tcon;
534         u32 ssid, tsid, newsid;
535         u16 tclass;
536         ssize_t length;
537         char *newcon;
538         u32 len;
539
540         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
541         if (length)
542                 return length;
543
544         length = -ENOMEM;
545         scon = kzalloc(size+1, GFP_KERNEL);
546         if (!scon)
547                 return length;
548
549         tcon = kzalloc(size+1, GFP_KERNEL);
550         if (!tcon)
551                 goto out;
552
553         length = -EINVAL;
554         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
555                 goto out2;
556
557         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
558         if (length < 0)
559                 goto out2;
560         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
561         if (length < 0)
562                 goto out2;
563
564         length = security_transition_sid(ssid, tsid, tclass, &newsid);
565         if (length < 0)
566                 goto out2;
567
568         length = security_sid_to_context(newsid, &newcon, &len);
569         if (length < 0)
570                 goto out2;
571
572         if (len > SIMPLE_TRANSACTION_LIMIT) {
573                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
574                        "max\n", __FUNCTION__, len);
575                 length = -ERANGE;
576                 goto out3;
577         }
578
579         memcpy(buf, newcon, len);
580         length = len;
581 out3:
582         kfree(newcon);
583 out2:
584         kfree(tcon);
585 out:
586         kfree(scon);
587         return length;
588 }
589
590 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size)
591 {
592         char *scon, *tcon;
593         u32 ssid, tsid, newsid;
594         u16 tclass;
595         ssize_t length;
596         char *newcon;
597         u32 len;
598
599         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
600         if (length)
601                 return length;
602
603         length = -ENOMEM;
604         scon = kzalloc(size+1, GFP_KERNEL);
605         if (!scon)
606                 return length;
607
608         tcon = kzalloc(size+1, GFP_KERNEL);
609         if (!tcon)
610                 goto out;
611
612         length = -EINVAL;
613         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
614                 goto out2;
615
616         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
617         if (length < 0)
618                 goto out2;
619         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
620         if (length < 0)
621                 goto out2;
622
623         length = security_change_sid(ssid, tsid, tclass, &newsid);
624         if (length < 0)
625                 goto out2;
626
627         length = security_sid_to_context(newsid, &newcon, &len);
628         if (length < 0)
629                 goto out2;
630
631         if (len > SIMPLE_TRANSACTION_LIMIT) {
632                 length = -ERANGE;
633                 goto out3;
634         }
635
636         memcpy(buf, newcon, len);
637         length = len;
638 out3:
639         kfree(newcon);
640 out2:
641         kfree(tcon);
642 out:
643         kfree(scon);
644         return length;
645 }
646
647 static ssize_t sel_write_user(struct file * file, char *buf, size_t size)
648 {
649         char *con, *user, *ptr;
650         u32 sid, *sids;
651         ssize_t length;
652         char *newcon;
653         int i, rc;
654         u32 len, nsids;
655
656         length = task_has_security(current, SECURITY__COMPUTE_USER);
657         if (length)
658                 return length;
659
660         length = -ENOMEM;
661         con = kzalloc(size+1, GFP_KERNEL);
662         if (!con)
663                 return length;
664
665         user = kzalloc(size+1, GFP_KERNEL);
666         if (!user)
667                 goto out;
668
669         length = -EINVAL;
670         if (sscanf(buf, "%s %s", con, user) != 2)
671                 goto out2;
672
673         length = security_context_to_sid(con, strlen(con)+1, &sid);
674         if (length < 0)
675                 goto out2;
676
677         length = security_get_user_sids(sid, user, &sids, &nsids);
678         if (length < 0)
679                 goto out2;
680
681         length = sprintf(buf, "%u", nsids) + 1;
682         ptr = buf + length;
683         for (i = 0; i < nsids; i++) {
684                 rc = security_sid_to_context(sids[i], &newcon, &len);
685                 if (rc) {
686                         length = rc;
687                         goto out3;
688                 }
689                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
690                         kfree(newcon);
691                         length = -ERANGE;
692                         goto out3;
693                 }
694                 memcpy(ptr, newcon, len);
695                 kfree(newcon);
696                 ptr += len;
697                 length += len;
698         }
699 out3:
700         kfree(sids);
701 out2:
702         kfree(user);
703 out:
704         kfree(con);
705         return length;
706 }
707
708 static ssize_t sel_write_member(struct file * file, char *buf, size_t size)
709 {
710         char *scon, *tcon;
711         u32 ssid, tsid, newsid;
712         u16 tclass;
713         ssize_t length;
714         char *newcon;
715         u32 len;
716
717         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
718         if (length)
719                 return length;
720
721         length = -ENOMEM;
722         scon = kzalloc(size+1, GFP_KERNEL);
723         if (!scon)
724                 return length;
725
726         tcon = kzalloc(size+1, GFP_KERNEL);
727         if (!tcon)
728                 goto out;
729
730         length = -EINVAL;
731         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
732                 goto out2;
733
734         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
735         if (length < 0)
736                 goto out2;
737         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
738         if (length < 0)
739                 goto out2;
740
741         length = security_member_sid(ssid, tsid, tclass, &newsid);
742         if (length < 0)
743                 goto out2;
744
745         length = security_sid_to_context(newsid, &newcon, &len);
746         if (length < 0)
747                 goto out2;
748
749         if (len > SIMPLE_TRANSACTION_LIMIT) {
750                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
751                        "max\n", __FUNCTION__, len);
752                 length = -ERANGE;
753                 goto out3;
754         }
755
756         memcpy(buf, newcon, len);
757         length = len;
758 out3:
759         kfree(newcon);
760 out2:
761         kfree(tcon);
762 out:
763         kfree(scon);
764         return length;
765 }
766
767 static struct inode *sel_make_inode(struct super_block *sb, int mode)
768 {
769         struct inode *ret = new_inode(sb);
770
771         if (ret) {
772                 ret->i_mode = mode;
773                 ret->i_uid = ret->i_gid = 0;
774                 ret->i_blocks = 0;
775                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
776         }
777         return ret;
778 }
779
780 #define BOOL_INO_OFFSET 30
781
782 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
783                              size_t count, loff_t *ppos)
784 {
785         char *page = NULL;
786         ssize_t length;
787         ssize_t ret;
788         int cur_enforcing;
789         struct inode *inode;
790
791         mutex_lock(&sel_mutex);
792
793         ret = -EFAULT;
794
795         /* check to see if this file has been deleted */
796         if (!filep->f_op)
797                 goto out;
798
799         if (count > PAGE_SIZE) {
800                 ret = -EINVAL;
801                 goto out;
802         }
803         if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) {
804                 ret = -ENOMEM;
805                 goto out;
806         }
807
808         inode = filep->f_dentry->d_inode;
809         cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET);
810         if (cur_enforcing < 0) {
811                 ret = cur_enforcing;
812                 goto out;
813         }
814
815         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
816                           bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]);
817         ret = simple_read_from_buffer(buf, count, ppos, page, length);
818 out:
819         mutex_unlock(&sel_mutex);
820         if (page)
821                 free_page((unsigned long)page);
822         return ret;
823 }
824
825 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
826                               size_t count, loff_t *ppos)
827 {
828         char *page = NULL;
829         ssize_t length = -EFAULT;
830         int new_value;
831         struct inode *inode;
832
833         mutex_lock(&sel_mutex);
834
835         length = task_has_security(current, SECURITY__SETBOOL);
836         if (length)
837                 goto out;
838
839         /* check to see if this file has been deleted */
840         if (!filep->f_op)
841                 goto out;
842
843         if (count >= PAGE_SIZE) {
844                 length = -ENOMEM;
845                 goto out;
846         }
847         if (*ppos != 0) {
848                 /* No partial writes. */
849                 goto out;
850         }
851         page = (char*)get_zeroed_page(GFP_KERNEL);
852         if (!page) {
853                 length = -ENOMEM;
854                 goto out;
855         }
856
857         if (copy_from_user(page, buf, count))
858                 goto out;
859
860         length = -EINVAL;
861         if (sscanf(page, "%d", &new_value) != 1)
862                 goto out;
863
864         if (new_value)
865                 new_value = 1;
866
867         inode = filep->f_dentry->d_inode;
868         bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = new_value;
869         length = count;
870
871 out:
872         mutex_unlock(&sel_mutex);
873         if (page)
874                 free_page((unsigned long) page);
875         return length;
876 }
877
878 static struct file_operations sel_bool_ops = {
879         .read           = sel_read_bool,
880         .write          = sel_write_bool,
881 };
882
883 static ssize_t sel_commit_bools_write(struct file *filep,
884                                       const char __user *buf,
885                                       size_t count, loff_t *ppos)
886 {
887         char *page = NULL;
888         ssize_t length = -EFAULT;
889         int new_value;
890
891         mutex_lock(&sel_mutex);
892
893         length = task_has_security(current, SECURITY__SETBOOL);
894         if (length)
895                 goto out;
896
897         /* check to see if this file has been deleted */
898         if (!filep->f_op)
899                 goto out;
900
901         if (count >= PAGE_SIZE) {
902                 length = -ENOMEM;
903                 goto out;
904         }
905         if (*ppos != 0) {
906                 /* No partial writes. */
907                 goto out;
908         }
909         page = (char*)get_zeroed_page(GFP_KERNEL);
910         if (!page) {
911                 length = -ENOMEM;
912                 goto out;
913         }
914
915         if (copy_from_user(page, buf, count))
916                 goto out;
917
918         length = -EINVAL;
919         if (sscanf(page, "%d", &new_value) != 1)
920                 goto out;
921
922         if (new_value && bool_pending_values) {
923                 security_set_bools(bool_num, bool_pending_values);
924         }
925
926         length = count;
927
928 out:
929         mutex_unlock(&sel_mutex);
930         if (page)
931                 free_page((unsigned long) page);
932         return length;
933 }
934
935 static struct file_operations sel_commit_bools_ops = {
936         .write          = sel_commit_bools_write,
937 };
938
939 /* delete booleans - partial revoke() from
940  * fs/proc/generic.c proc_kill_inodes */
941 static void sel_remove_bools(struct dentry *de)
942 {
943         struct list_head *p, *node;
944         struct super_block *sb = de->d_sb;
945
946         spin_lock(&dcache_lock);
947         node = de->d_subdirs.next;
948         while (node != &de->d_subdirs) {
949                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
950                 list_del_init(node);
951
952                 if (d->d_inode) {
953                         d = dget_locked(d);
954                         spin_unlock(&dcache_lock);
955                         d_delete(d);
956                         simple_unlink(de->d_inode, d);
957                         dput(d);
958                         spin_lock(&dcache_lock);
959                 }
960                 node = de->d_subdirs.next;
961         }
962
963         spin_unlock(&dcache_lock);
964
965         file_list_lock();
966         list_for_each(p, &sb->s_files) {
967                 struct file * filp = list_entry(p, struct file, f_u.fu_list);
968                 struct dentry * dentry = filp->f_dentry;
969
970                 if (dentry->d_parent != de) {
971                         continue;
972                 }
973                 filp->f_op = NULL;
974         }
975         file_list_unlock();
976 }
977
978 #define BOOL_DIR_NAME "booleans"
979
980 static int sel_make_bools(void)
981 {
982         int i, ret = 0;
983         ssize_t len;
984         struct dentry *dentry = NULL;
985         struct dentry *dir = bool_dir;
986         struct inode *inode = NULL;
987         struct inode_security_struct *isec;
988         char **names = NULL, *page;
989         int num;
990         int *values = NULL;
991         u32 sid;
992
993         /* remove any existing files */
994         kfree(bool_pending_values);
995         bool_pending_values = NULL;
996
997         sel_remove_bools(dir);
998
999         if (!(page = (char*)get_zeroed_page(GFP_KERNEL)))
1000                 return -ENOMEM;
1001
1002         ret = security_get_bools(&num, &names, &values);
1003         if (ret != 0)
1004                 goto out;
1005
1006         for (i = 0; i < num; i++) {
1007                 dentry = d_alloc_name(dir, names[i]);
1008                 if (!dentry) {
1009                         ret = -ENOMEM;
1010                         goto err;
1011                 }
1012                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1013                 if (!inode) {
1014                         ret = -ENOMEM;
1015                         goto err;
1016                 }
1017
1018                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1019                 if (len < 0) {
1020                         ret = -EINVAL;
1021                         goto err;
1022                 } else if (len >= PAGE_SIZE) {
1023                         ret = -ENAMETOOLONG;
1024                         goto err;
1025                 }
1026                 isec = (struct inode_security_struct*)inode->i_security;
1027                 if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid)))
1028                         goto err;
1029                 isec->sid = sid;
1030                 isec->initialized = 1;
1031                 inode->i_fop = &sel_bool_ops;
1032                 inode->i_ino = i + BOOL_INO_OFFSET;
1033                 d_add(dentry, inode);
1034         }
1035         bool_num = num;
1036         bool_pending_values = values;
1037 out:
1038         free_page((unsigned long)page);
1039         if (names) {
1040                 for (i = 0; i < num; i++)
1041                         kfree(names[i]);
1042                 kfree(names);
1043         }
1044         return ret;
1045 err:
1046         kfree(values);
1047         sel_remove_bools(dir);
1048         ret = -ENOMEM;
1049         goto out;
1050 }
1051
1052 #define NULL_FILE_NAME "null"
1053
1054 struct dentry *selinux_null = NULL;
1055
1056 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1057                                             size_t count, loff_t *ppos)
1058 {
1059         char tmpbuf[TMPBUFLEN];
1060         ssize_t length;
1061
1062         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1063         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1064 }
1065
1066 static ssize_t sel_write_avc_cache_threshold(struct file * file,
1067                                              const char __user * buf,
1068                                              size_t count, loff_t *ppos)
1069
1070 {
1071         char *page;
1072         ssize_t ret;
1073         int new_value;
1074
1075         if (count >= PAGE_SIZE) {
1076                 ret = -ENOMEM;
1077                 goto out;
1078         }
1079
1080         if (*ppos != 0) {
1081                 /* No partial writes. */
1082                 ret = -EINVAL;
1083                 goto out;
1084         }
1085
1086         page = (char*)get_zeroed_page(GFP_KERNEL);
1087         if (!page) {
1088                 ret = -ENOMEM;
1089                 goto out;
1090         }
1091
1092         if (copy_from_user(page, buf, count)) {
1093                 ret = -EFAULT;
1094                 goto out_free;
1095         }
1096
1097         if (sscanf(page, "%u", &new_value) != 1) {
1098                 ret = -EINVAL;
1099                 goto out;
1100         }
1101
1102         if (new_value != avc_cache_threshold) {
1103                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1104                 if (ret)
1105                         goto out_free;
1106                 avc_cache_threshold = new_value;
1107         }
1108         ret = count;
1109 out_free:
1110         free_page((unsigned long)page);
1111 out:
1112         return ret;
1113 }
1114
1115 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1116                                        size_t count, loff_t *ppos)
1117 {
1118         char *page;
1119         ssize_t ret = 0;
1120
1121         page = (char *)__get_free_page(GFP_KERNEL);
1122         if (!page) {
1123                 ret = -ENOMEM;
1124                 goto out;
1125         }
1126         ret = avc_get_hash_stats(page);
1127         if (ret >= 0)
1128                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1129         free_page((unsigned long)page);
1130 out:
1131         return ret;
1132 }
1133
1134 static struct file_operations sel_avc_cache_threshold_ops = {
1135         .read           = sel_read_avc_cache_threshold,
1136         .write          = sel_write_avc_cache_threshold,
1137 };
1138
1139 static struct file_operations sel_avc_hash_stats_ops = {
1140         .read           = sel_read_avc_hash_stats,
1141 };
1142
1143 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1144 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1145 {
1146         int cpu;
1147
1148         for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1149                 if (!cpu_possible(cpu))
1150                         continue;
1151                 *idx = cpu + 1;
1152                 return &per_cpu(avc_cache_stats, cpu);
1153         }
1154         return NULL;
1155 }
1156
1157 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1158 {
1159         loff_t n = *pos - 1;
1160
1161         if (*pos == 0)
1162                 return SEQ_START_TOKEN;
1163
1164         return sel_avc_get_stat_idx(&n);
1165 }
1166
1167 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1168 {
1169         return sel_avc_get_stat_idx(pos);
1170 }
1171
1172 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1173 {
1174         struct avc_cache_stats *st = v;
1175
1176         if (v == SEQ_START_TOKEN)
1177                 seq_printf(seq, "lookups hits misses allocations reclaims "
1178                            "frees\n");
1179         else
1180                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1181                            st->hits, st->misses, st->allocations,
1182                            st->reclaims, st->frees);
1183         return 0;
1184 }
1185
1186 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1187 { }
1188
1189 static struct seq_operations sel_avc_cache_stats_seq_ops = {
1190         .start          = sel_avc_stats_seq_start,
1191         .next           = sel_avc_stats_seq_next,
1192         .show           = sel_avc_stats_seq_show,
1193         .stop           = sel_avc_stats_seq_stop,
1194 };
1195
1196 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1197 {
1198         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1199 }
1200
1201 static struct file_operations sel_avc_cache_stats_ops = {
1202         .open           = sel_open_avc_cache_stats,
1203         .read           = seq_read,
1204         .llseek         = seq_lseek,
1205         .release        = seq_release,
1206 };
1207 #endif
1208
1209 static int sel_make_avc_files(struct dentry *dir)
1210 {
1211         int i, ret = 0;
1212         static struct tree_descr files[] = {
1213                 { "cache_threshold",
1214                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1215                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1216 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1217                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1218 #endif
1219         };
1220
1221         for (i = 0; i < ARRAY_SIZE(files); i++) {
1222                 struct inode *inode;
1223                 struct dentry *dentry;
1224
1225                 dentry = d_alloc_name(dir, files[i].name);
1226                 if (!dentry) {
1227                         ret = -ENOMEM;
1228                         goto out;
1229                 }
1230
1231                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1232                 if (!inode) {
1233                         ret = -ENOMEM;
1234                         goto out;
1235                 }
1236                 inode->i_fop = files[i].ops;
1237                 d_add(dentry, inode);
1238         }
1239 out:
1240         return ret;
1241 }
1242
1243 static int sel_make_dir(struct inode *dir, struct dentry *dentry)
1244 {
1245         int ret = 0;
1246         struct inode *inode;
1247
1248         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1249         if (!inode) {
1250                 ret = -ENOMEM;
1251                 goto out;
1252         }
1253         inode->i_op = &simple_dir_inode_operations;
1254         inode->i_fop = &simple_dir_operations;
1255         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1256         inode->i_nlink++;
1257         d_add(dentry, inode);
1258         /* bump link count on parent directory, too */
1259         dir->i_nlink++;
1260 out:
1261         return ret;
1262 }
1263
1264 static int sel_fill_super(struct super_block * sb, void * data, int silent)
1265 {
1266         int ret;
1267         struct dentry *dentry;
1268         struct inode *inode, *root_inode;
1269         struct inode_security_struct *isec;
1270
1271         static struct tree_descr selinux_files[] = {
1272                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1273                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1274                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1275                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1276                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1277                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1278                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1279                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1280                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1281                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1282                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1283                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1284                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1285                 [SEL_COMPAT_NET] = {"compat_net", &sel_compat_net_ops, S_IRUGO|S_IWUSR},
1286                 /* last one */ {""}
1287         };
1288         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1289         if (ret)
1290                 goto err;
1291
1292         root_inode = sb->s_root->d_inode;
1293
1294         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1295         if (!dentry) {
1296                 ret = -ENOMEM;
1297                 goto err;
1298         }
1299
1300         ret = sel_make_dir(root_inode, dentry);
1301         if (ret)
1302                 goto err;
1303
1304         bool_dir = dentry;
1305
1306         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1307         if (!dentry) {
1308                 ret = -ENOMEM;
1309                 goto err;
1310         }
1311
1312         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1313         if (!inode) {
1314                 ret = -ENOMEM;
1315                 goto err;
1316         }
1317         isec = (struct inode_security_struct*)inode->i_security;
1318         isec->sid = SECINITSID_DEVNULL;
1319         isec->sclass = SECCLASS_CHR_FILE;
1320         isec->initialized = 1;
1321
1322         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1323         d_add(dentry, inode);
1324         selinux_null = dentry;
1325
1326         dentry = d_alloc_name(sb->s_root, "avc");
1327         if (!dentry) {
1328                 ret = -ENOMEM;
1329                 goto err;
1330         }
1331
1332         ret = sel_make_dir(root_inode, dentry);
1333         if (ret)
1334                 goto err;
1335
1336         ret = sel_make_avc_files(dentry);
1337         if (ret)
1338                 goto err;
1339 out:
1340         return ret;
1341 err:
1342         printk(KERN_ERR "%s:  failed while creating inodes\n", __FUNCTION__);
1343         goto out;
1344 }
1345
1346 static int sel_get_sb(struct file_system_type *fs_type,
1347                       int flags, const char *dev_name, void *data,
1348                       struct vfsmount *mnt)
1349 {
1350         return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
1351 }
1352
1353 static struct file_system_type sel_fs_type = {
1354         .name           = "selinuxfs",
1355         .get_sb         = sel_get_sb,
1356         .kill_sb        = kill_litter_super,
1357 };
1358
1359 struct vfsmount *selinuxfs_mount;
1360
1361 static int __init init_sel_fs(void)
1362 {
1363         int err;
1364
1365         if (!selinux_enabled)
1366                 return 0;
1367         err = register_filesystem(&sel_fs_type);
1368         if (!err) {
1369                 selinuxfs_mount = kern_mount(&sel_fs_type);
1370                 if (IS_ERR(selinuxfs_mount)) {
1371                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1372                         err = PTR_ERR(selinuxfs_mount);
1373                         selinuxfs_mount = NULL;
1374                 }
1375         }
1376         return err;
1377 }
1378
1379 __initcall(init_sel_fs);
1380
1381 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1382 void exit_sel_fs(void)
1383 {
1384         unregister_filesystem(&sel_fs_type);
1385 }
1386 #endif