fs: cleanup files_lock locking
[linux-2.6.git] / security / selinux / hooks.c
1 /*
2  *  NSA Security-Enhanced Linux (SELinux) security module
3  *
4  *  This file contains the SELinux hook function implementations.
5  *
6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
7  *            Chris Vance, <cvance@nai.com>
8  *            Wayne Salamon, <wsalamon@nai.com>
9  *            James Morris <jmorris@redhat.com>
10  *
11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *                                         Eric Paris <eparis@redhat.com>
14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15  *                          <dgoeddel@trustedcs.com>
16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17  *      Paul Moore <paul.moore@hp.com>
18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
20  *
21  *      This program is free software; you can redistribute it and/or modify
22  *      it under the terms of the GNU General Public License version 2,
23  *      as published by the Free Software Foundation.
24  */
25
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/tracehook.h>
29 #include <linux/errno.h>
30 #include <linux/sched.h>
31 #include <linux/security.h>
32 #include <linux/xattr.h>
33 #include <linux/capability.h>
34 #include <linux/unistd.h>
35 #include <linux/mm.h>
36 #include <linux/mman.h>
37 #include <linux/slab.h>
38 #include <linux/pagemap.h>
39 #include <linux/swap.h>
40 #include <linux/spinlock.h>
41 #include <linux/syscalls.h>
42 #include <linux/file.h>
43 #include <linux/fdtable.h>
44 #include <linux/namei.h>
45 #include <linux/mount.h>
46 #include <linux/proc_fs.h>
47 #include <linux/netfilter_ipv4.h>
48 #include <linux/netfilter_ipv6.h>
49 #include <linux/tty.h>
50 #include <net/icmp.h>
51 #include <net/ip.h>             /* for local_port_range[] */
52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
53 #include <net/net_namespace.h>
54 #include <net/netlabel.h>
55 #include <linux/uaccess.h>
56 #include <asm/ioctls.h>
57 #include <asm/atomic.h>
58 #include <linux/bitops.h>
59 #include <linux/interrupt.h>
60 #include <linux/netdevice.h>    /* for network interface checks */
61 #include <linux/netlink.h>
62 #include <linux/tcp.h>
63 #include <linux/udp.h>
64 #include <linux/dccp.h>
65 #include <linux/quota.h>
66 #include <linux/un.h>           /* for Unix socket types */
67 #include <net/af_unix.h>        /* for Unix socket types */
68 #include <linux/parser.h>
69 #include <linux/nfs_mount.h>
70 #include <net/ipv6.h>
71 #include <linux/hugetlb.h>
72 #include <linux/personality.h>
73 #include <linux/sysctl.h>
74 #include <linux/audit.h>
75 #include <linux/string.h>
76 #include <linux/selinux.h>
77 #include <linux/mutex.h>
78 #include <linux/posix-timers.h>
79 #include <linux/syslog.h>
80
81 #include "avc.h"
82 #include "objsec.h"
83 #include "netif.h"
84 #include "netnode.h"
85 #include "netport.h"
86 #include "xfrm.h"
87 #include "netlabel.h"
88 #include "audit.h"
89
90 #define NUM_SEL_MNT_OPTS 5
91
92 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
93 extern struct security_operations *security_ops;
94
95 /* SECMARK reference count */
96 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
97
98 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
99 int selinux_enforcing;
100
101 static int __init enforcing_setup(char *str)
102 {
103         unsigned long enforcing;
104         if (!strict_strtoul(str, 0, &enforcing))
105                 selinux_enforcing = enforcing ? 1 : 0;
106         return 1;
107 }
108 __setup("enforcing=", enforcing_setup);
109 #endif
110
111 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
112 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
113
114 static int __init selinux_enabled_setup(char *str)
115 {
116         unsigned long enabled;
117         if (!strict_strtoul(str, 0, &enabled))
118                 selinux_enabled = enabled ? 1 : 0;
119         return 1;
120 }
121 __setup("selinux=", selinux_enabled_setup);
122 #else
123 int selinux_enabled = 1;
124 #endif
125
126 static struct kmem_cache *sel_inode_cache;
127
128 /**
129  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
130  *
131  * Description:
132  * This function checks the SECMARK reference counter to see if any SECMARK
133  * targets are currently configured, if the reference counter is greater than
134  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
135  * enabled, false (0) if SECMARK is disabled.
136  *
137  */
138 static int selinux_secmark_enabled(void)
139 {
140         return (atomic_read(&selinux_secmark_refcount) > 0);
141 }
142
143 /*
144  * initialise the security for the init task
145  */
146 static void cred_init_security(void)
147 {
148         struct cred *cred = (struct cred *) current->real_cred;
149         struct task_security_struct *tsec;
150
151         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
152         if (!tsec)
153                 panic("SELinux:  Failed to initialize initial task.\n");
154
155         tsec->osid = tsec->sid = SECINITSID_KERNEL;
156         cred->security = tsec;
157 }
158
159 /*
160  * get the security ID of a set of credentials
161  */
162 static inline u32 cred_sid(const struct cred *cred)
163 {
164         const struct task_security_struct *tsec;
165
166         tsec = cred->security;
167         return tsec->sid;
168 }
169
170 /*
171  * get the objective security ID of a task
172  */
173 static inline u32 task_sid(const struct task_struct *task)
174 {
175         u32 sid;
176
177         rcu_read_lock();
178         sid = cred_sid(__task_cred(task));
179         rcu_read_unlock();
180         return sid;
181 }
182
183 /*
184  * get the subjective security ID of the current task
185  */
186 static inline u32 current_sid(void)
187 {
188         const struct task_security_struct *tsec = current_security();
189
190         return tsec->sid;
191 }
192
193 /* Allocate and free functions for each kind of security blob. */
194
195 static int inode_alloc_security(struct inode *inode)
196 {
197         struct inode_security_struct *isec;
198         u32 sid = current_sid();
199
200         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
201         if (!isec)
202                 return -ENOMEM;
203
204         mutex_init(&isec->lock);
205         INIT_LIST_HEAD(&isec->list);
206         isec->inode = inode;
207         isec->sid = SECINITSID_UNLABELED;
208         isec->sclass = SECCLASS_FILE;
209         isec->task_sid = sid;
210         inode->i_security = isec;
211
212         return 0;
213 }
214
215 static void inode_free_security(struct inode *inode)
216 {
217         struct inode_security_struct *isec = inode->i_security;
218         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
219
220         spin_lock(&sbsec->isec_lock);
221         if (!list_empty(&isec->list))
222                 list_del_init(&isec->list);
223         spin_unlock(&sbsec->isec_lock);
224
225         inode->i_security = NULL;
226         kmem_cache_free(sel_inode_cache, isec);
227 }
228
229 static int file_alloc_security(struct file *file)
230 {
231         struct file_security_struct *fsec;
232         u32 sid = current_sid();
233
234         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
235         if (!fsec)
236                 return -ENOMEM;
237
238         fsec->sid = sid;
239         fsec->fown_sid = sid;
240         file->f_security = fsec;
241
242         return 0;
243 }
244
245 static void file_free_security(struct file *file)
246 {
247         struct file_security_struct *fsec = file->f_security;
248         file->f_security = NULL;
249         kfree(fsec);
250 }
251
252 static int superblock_alloc_security(struct super_block *sb)
253 {
254         struct superblock_security_struct *sbsec;
255
256         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
257         if (!sbsec)
258                 return -ENOMEM;
259
260         mutex_init(&sbsec->lock);
261         INIT_LIST_HEAD(&sbsec->isec_head);
262         spin_lock_init(&sbsec->isec_lock);
263         sbsec->sb = sb;
264         sbsec->sid = SECINITSID_UNLABELED;
265         sbsec->def_sid = SECINITSID_FILE;
266         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
267         sb->s_security = sbsec;
268
269         return 0;
270 }
271
272 static void superblock_free_security(struct super_block *sb)
273 {
274         struct superblock_security_struct *sbsec = sb->s_security;
275         sb->s_security = NULL;
276         kfree(sbsec);
277 }
278
279 /* The security server must be initialized before
280    any labeling or access decisions can be provided. */
281 extern int ss_initialized;
282
283 /* The file system's label must be initialized prior to use. */
284
285 static const char *labeling_behaviors[6] = {
286         "uses xattr",
287         "uses transition SIDs",
288         "uses task SIDs",
289         "uses genfs_contexts",
290         "not configured for labeling",
291         "uses mountpoint labeling",
292 };
293
294 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
295
296 static inline int inode_doinit(struct inode *inode)
297 {
298         return inode_doinit_with_dentry(inode, NULL);
299 }
300
301 enum {
302         Opt_error = -1,
303         Opt_context = 1,
304         Opt_fscontext = 2,
305         Opt_defcontext = 3,
306         Opt_rootcontext = 4,
307         Opt_labelsupport = 5,
308 };
309
310 static const match_table_t tokens = {
311         {Opt_context, CONTEXT_STR "%s"},
312         {Opt_fscontext, FSCONTEXT_STR "%s"},
313         {Opt_defcontext, DEFCONTEXT_STR "%s"},
314         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
315         {Opt_labelsupport, LABELSUPP_STR},
316         {Opt_error, NULL},
317 };
318
319 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
320
321 static int may_context_mount_sb_relabel(u32 sid,
322                         struct superblock_security_struct *sbsec,
323                         const struct cred *cred)
324 {
325         const struct task_security_struct *tsec = cred->security;
326         int rc;
327
328         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
329                           FILESYSTEM__RELABELFROM, NULL);
330         if (rc)
331                 return rc;
332
333         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
334                           FILESYSTEM__RELABELTO, NULL);
335         return rc;
336 }
337
338 static int may_context_mount_inode_relabel(u32 sid,
339                         struct superblock_security_struct *sbsec,
340                         const struct cred *cred)
341 {
342         const struct task_security_struct *tsec = cred->security;
343         int rc;
344         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
345                           FILESYSTEM__RELABELFROM, NULL);
346         if (rc)
347                 return rc;
348
349         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
350                           FILESYSTEM__ASSOCIATE, NULL);
351         return rc;
352 }
353
354 static int sb_finish_set_opts(struct super_block *sb)
355 {
356         struct superblock_security_struct *sbsec = sb->s_security;
357         struct dentry *root = sb->s_root;
358         struct inode *root_inode = root->d_inode;
359         int rc = 0;
360
361         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
362                 /* Make sure that the xattr handler exists and that no
363                    error other than -ENODATA is returned by getxattr on
364                    the root directory.  -ENODATA is ok, as this may be
365                    the first boot of the SELinux kernel before we have
366                    assigned xattr values to the filesystem. */
367                 if (!root_inode->i_op->getxattr) {
368                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
369                                "xattr support\n", sb->s_id, sb->s_type->name);
370                         rc = -EOPNOTSUPP;
371                         goto out;
372                 }
373                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
374                 if (rc < 0 && rc != -ENODATA) {
375                         if (rc == -EOPNOTSUPP)
376                                 printk(KERN_WARNING "SELinux: (dev %s, type "
377                                        "%s) has no security xattr handler\n",
378                                        sb->s_id, sb->s_type->name);
379                         else
380                                 printk(KERN_WARNING "SELinux: (dev %s, type "
381                                        "%s) getxattr errno %d\n", sb->s_id,
382                                        sb->s_type->name, -rc);
383                         goto out;
384                 }
385         }
386
387         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
388
389         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
390                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
391                        sb->s_id, sb->s_type->name);
392         else
393                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
394                        sb->s_id, sb->s_type->name,
395                        labeling_behaviors[sbsec->behavior-1]);
396
397         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
398             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
399             sbsec->behavior == SECURITY_FS_USE_NONE ||
400             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
401                 sbsec->flags &= ~SE_SBLABELSUPP;
402
403         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
404         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
405                 sbsec->flags |= SE_SBLABELSUPP;
406
407         /* Initialize the root inode. */
408         rc = inode_doinit_with_dentry(root_inode, root);
409
410         /* Initialize any other inodes associated with the superblock, e.g.
411            inodes created prior to initial policy load or inodes created
412            during get_sb by a pseudo filesystem that directly
413            populates itself. */
414         spin_lock(&sbsec->isec_lock);
415 next_inode:
416         if (!list_empty(&sbsec->isec_head)) {
417                 struct inode_security_struct *isec =
418                                 list_entry(sbsec->isec_head.next,
419                                            struct inode_security_struct, list);
420                 struct inode *inode = isec->inode;
421                 spin_unlock(&sbsec->isec_lock);
422                 inode = igrab(inode);
423                 if (inode) {
424                         if (!IS_PRIVATE(inode))
425                                 inode_doinit(inode);
426                         iput(inode);
427                 }
428                 spin_lock(&sbsec->isec_lock);
429                 list_del_init(&isec->list);
430                 goto next_inode;
431         }
432         spin_unlock(&sbsec->isec_lock);
433 out:
434         return rc;
435 }
436
437 /*
438  * This function should allow an FS to ask what it's mount security
439  * options were so it can use those later for submounts, displaying
440  * mount options, or whatever.
441  */
442 static int selinux_get_mnt_opts(const struct super_block *sb,
443                                 struct security_mnt_opts *opts)
444 {
445         int rc = 0, i;
446         struct superblock_security_struct *sbsec = sb->s_security;
447         char *context = NULL;
448         u32 len;
449         char tmp;
450
451         security_init_mnt_opts(opts);
452
453         if (!(sbsec->flags & SE_SBINITIALIZED))
454                 return -EINVAL;
455
456         if (!ss_initialized)
457                 return -EINVAL;
458
459         tmp = sbsec->flags & SE_MNTMASK;
460         /* count the number of mount options for this sb */
461         for (i = 0; i < 8; i++) {
462                 if (tmp & 0x01)
463                         opts->num_mnt_opts++;
464                 tmp >>= 1;
465         }
466         /* Check if the Label support flag is set */
467         if (sbsec->flags & SE_SBLABELSUPP)
468                 opts->num_mnt_opts++;
469
470         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
471         if (!opts->mnt_opts) {
472                 rc = -ENOMEM;
473                 goto out_free;
474         }
475
476         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
477         if (!opts->mnt_opts_flags) {
478                 rc = -ENOMEM;
479                 goto out_free;
480         }
481
482         i = 0;
483         if (sbsec->flags & FSCONTEXT_MNT) {
484                 rc = security_sid_to_context(sbsec->sid, &context, &len);
485                 if (rc)
486                         goto out_free;
487                 opts->mnt_opts[i] = context;
488                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
489         }
490         if (sbsec->flags & CONTEXT_MNT) {
491                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
492                 if (rc)
493                         goto out_free;
494                 opts->mnt_opts[i] = context;
495                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
496         }
497         if (sbsec->flags & DEFCONTEXT_MNT) {
498                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
499                 if (rc)
500                         goto out_free;
501                 opts->mnt_opts[i] = context;
502                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
503         }
504         if (sbsec->flags & ROOTCONTEXT_MNT) {
505                 struct inode *root = sbsec->sb->s_root->d_inode;
506                 struct inode_security_struct *isec = root->i_security;
507
508                 rc = security_sid_to_context(isec->sid, &context, &len);
509                 if (rc)
510                         goto out_free;
511                 opts->mnt_opts[i] = context;
512                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
513         }
514         if (sbsec->flags & SE_SBLABELSUPP) {
515                 opts->mnt_opts[i] = NULL;
516                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
517         }
518
519         BUG_ON(i != opts->num_mnt_opts);
520
521         return 0;
522
523 out_free:
524         security_free_mnt_opts(opts);
525         return rc;
526 }
527
528 static int bad_option(struct superblock_security_struct *sbsec, char flag,
529                       u32 old_sid, u32 new_sid)
530 {
531         char mnt_flags = sbsec->flags & SE_MNTMASK;
532
533         /* check if the old mount command had the same options */
534         if (sbsec->flags & SE_SBINITIALIZED)
535                 if (!(sbsec->flags & flag) ||
536                     (old_sid != new_sid))
537                         return 1;
538
539         /* check if we were passed the same options twice,
540          * aka someone passed context=a,context=b
541          */
542         if (!(sbsec->flags & SE_SBINITIALIZED))
543                 if (mnt_flags & flag)
544                         return 1;
545         return 0;
546 }
547
548 /*
549  * Allow filesystems with binary mount data to explicitly set mount point
550  * labeling information.
551  */
552 static int selinux_set_mnt_opts(struct super_block *sb,
553                                 struct security_mnt_opts *opts)
554 {
555         const struct cred *cred = current_cred();
556         int rc = 0, i;
557         struct superblock_security_struct *sbsec = sb->s_security;
558         const char *name = sb->s_type->name;
559         struct inode *inode = sbsec->sb->s_root->d_inode;
560         struct inode_security_struct *root_isec = inode->i_security;
561         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
562         u32 defcontext_sid = 0;
563         char **mount_options = opts->mnt_opts;
564         int *flags = opts->mnt_opts_flags;
565         int num_opts = opts->num_mnt_opts;
566
567         mutex_lock(&sbsec->lock);
568
569         if (!ss_initialized) {
570                 if (!num_opts) {
571                         /* Defer initialization until selinux_complete_init,
572                            after the initial policy is loaded and the security
573                            server is ready to handle calls. */
574                         goto out;
575                 }
576                 rc = -EINVAL;
577                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
578                         "before the security server is initialized\n");
579                 goto out;
580         }
581
582         /*
583          * Binary mount data FS will come through this function twice.  Once
584          * from an explicit call and once from the generic calls from the vfs.
585          * Since the generic VFS calls will not contain any security mount data
586          * we need to skip the double mount verification.
587          *
588          * This does open a hole in which we will not notice if the first
589          * mount using this sb set explict options and a second mount using
590          * this sb does not set any security options.  (The first options
591          * will be used for both mounts)
592          */
593         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
594             && (num_opts == 0))
595                 goto out;
596
597         /*
598          * parse the mount options, check if they are valid sids.
599          * also check if someone is trying to mount the same sb more
600          * than once with different security options.
601          */
602         for (i = 0; i < num_opts; i++) {
603                 u32 sid;
604
605                 if (flags[i] == SE_SBLABELSUPP)
606                         continue;
607                 rc = security_context_to_sid(mount_options[i],
608                                              strlen(mount_options[i]), &sid);
609                 if (rc) {
610                         printk(KERN_WARNING "SELinux: security_context_to_sid"
611                                "(%s) failed for (dev %s, type %s) errno=%d\n",
612                                mount_options[i], sb->s_id, name, rc);
613                         goto out;
614                 }
615                 switch (flags[i]) {
616                 case FSCONTEXT_MNT:
617                         fscontext_sid = sid;
618
619                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
620                                         fscontext_sid))
621                                 goto out_double_mount;
622
623                         sbsec->flags |= FSCONTEXT_MNT;
624                         break;
625                 case CONTEXT_MNT:
626                         context_sid = sid;
627
628                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
629                                         context_sid))
630                                 goto out_double_mount;
631
632                         sbsec->flags |= CONTEXT_MNT;
633                         break;
634                 case ROOTCONTEXT_MNT:
635                         rootcontext_sid = sid;
636
637                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
638                                         rootcontext_sid))
639                                 goto out_double_mount;
640
641                         sbsec->flags |= ROOTCONTEXT_MNT;
642
643                         break;
644                 case DEFCONTEXT_MNT:
645                         defcontext_sid = sid;
646
647                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
648                                         defcontext_sid))
649                                 goto out_double_mount;
650
651                         sbsec->flags |= DEFCONTEXT_MNT;
652
653                         break;
654                 default:
655                         rc = -EINVAL;
656                         goto out;
657                 }
658         }
659
660         if (sbsec->flags & SE_SBINITIALIZED) {
661                 /* previously mounted with options, but not on this attempt? */
662                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
663                         goto out_double_mount;
664                 rc = 0;
665                 goto out;
666         }
667
668         if (strcmp(sb->s_type->name, "proc") == 0)
669                 sbsec->flags |= SE_SBPROC;
670
671         /* Determine the labeling behavior to use for this filesystem type. */
672         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
673         if (rc) {
674                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
675                        __func__, sb->s_type->name, rc);
676                 goto out;
677         }
678
679         /* sets the context of the superblock for the fs being mounted. */
680         if (fscontext_sid) {
681                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
682                 if (rc)
683                         goto out;
684
685                 sbsec->sid = fscontext_sid;
686         }
687
688         /*
689          * Switch to using mount point labeling behavior.
690          * sets the label used on all file below the mountpoint, and will set
691          * the superblock context if not already set.
692          */
693         if (context_sid) {
694                 if (!fscontext_sid) {
695                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
696                                                           cred);
697                         if (rc)
698                                 goto out;
699                         sbsec->sid = context_sid;
700                 } else {
701                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
702                                                              cred);
703                         if (rc)
704                                 goto out;
705                 }
706                 if (!rootcontext_sid)
707                         rootcontext_sid = context_sid;
708
709                 sbsec->mntpoint_sid = context_sid;
710                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
711         }
712
713         if (rootcontext_sid) {
714                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
715                                                      cred);
716                 if (rc)
717                         goto out;
718
719                 root_isec->sid = rootcontext_sid;
720                 root_isec->initialized = 1;
721         }
722
723         if (defcontext_sid) {
724                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
725                         rc = -EINVAL;
726                         printk(KERN_WARNING "SELinux: defcontext option is "
727                                "invalid for this filesystem type\n");
728                         goto out;
729                 }
730
731                 if (defcontext_sid != sbsec->def_sid) {
732                         rc = may_context_mount_inode_relabel(defcontext_sid,
733                                                              sbsec, cred);
734                         if (rc)
735                                 goto out;
736                 }
737
738                 sbsec->def_sid = defcontext_sid;
739         }
740
741         rc = sb_finish_set_opts(sb);
742 out:
743         mutex_unlock(&sbsec->lock);
744         return rc;
745 out_double_mount:
746         rc = -EINVAL;
747         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
748                "security settings for (dev %s, type %s)\n", sb->s_id, name);
749         goto out;
750 }
751
752 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
753                                         struct super_block *newsb)
754 {
755         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
756         struct superblock_security_struct *newsbsec = newsb->s_security;
757
758         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
759         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
760         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
761
762         /*
763          * if the parent was able to be mounted it clearly had no special lsm
764          * mount options.  thus we can safely deal with this superblock later
765          */
766         if (!ss_initialized)
767                 return;
768
769         /* how can we clone if the old one wasn't set up?? */
770         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
771
772         /* if fs is reusing a sb, just let its options stand... */
773         if (newsbsec->flags & SE_SBINITIALIZED)
774                 return;
775
776         mutex_lock(&newsbsec->lock);
777
778         newsbsec->flags = oldsbsec->flags;
779
780         newsbsec->sid = oldsbsec->sid;
781         newsbsec->def_sid = oldsbsec->def_sid;
782         newsbsec->behavior = oldsbsec->behavior;
783
784         if (set_context) {
785                 u32 sid = oldsbsec->mntpoint_sid;
786
787                 if (!set_fscontext)
788                         newsbsec->sid = sid;
789                 if (!set_rootcontext) {
790                         struct inode *newinode = newsb->s_root->d_inode;
791                         struct inode_security_struct *newisec = newinode->i_security;
792                         newisec->sid = sid;
793                 }
794                 newsbsec->mntpoint_sid = sid;
795         }
796         if (set_rootcontext) {
797                 const struct inode *oldinode = oldsb->s_root->d_inode;
798                 const struct inode_security_struct *oldisec = oldinode->i_security;
799                 struct inode *newinode = newsb->s_root->d_inode;
800                 struct inode_security_struct *newisec = newinode->i_security;
801
802                 newisec->sid = oldisec->sid;
803         }
804
805         sb_finish_set_opts(newsb);
806         mutex_unlock(&newsbsec->lock);
807 }
808
809 static int selinux_parse_opts_str(char *options,
810                                   struct security_mnt_opts *opts)
811 {
812         char *p;
813         char *context = NULL, *defcontext = NULL;
814         char *fscontext = NULL, *rootcontext = NULL;
815         int rc, num_mnt_opts = 0;
816
817         opts->num_mnt_opts = 0;
818
819         /* Standard string-based options. */
820         while ((p = strsep(&options, "|")) != NULL) {
821                 int token;
822                 substring_t args[MAX_OPT_ARGS];
823
824                 if (!*p)
825                         continue;
826
827                 token = match_token(p, tokens, args);
828
829                 switch (token) {
830                 case Opt_context:
831                         if (context || defcontext) {
832                                 rc = -EINVAL;
833                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
834                                 goto out_err;
835                         }
836                         context = match_strdup(&args[0]);
837                         if (!context) {
838                                 rc = -ENOMEM;
839                                 goto out_err;
840                         }
841                         break;
842
843                 case Opt_fscontext:
844                         if (fscontext) {
845                                 rc = -EINVAL;
846                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
847                                 goto out_err;
848                         }
849                         fscontext = match_strdup(&args[0]);
850                         if (!fscontext) {
851                                 rc = -ENOMEM;
852                                 goto out_err;
853                         }
854                         break;
855
856                 case Opt_rootcontext:
857                         if (rootcontext) {
858                                 rc = -EINVAL;
859                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
860                                 goto out_err;
861                         }
862                         rootcontext = match_strdup(&args[0]);
863                         if (!rootcontext) {
864                                 rc = -ENOMEM;
865                                 goto out_err;
866                         }
867                         break;
868
869                 case Opt_defcontext:
870                         if (context || defcontext) {
871                                 rc = -EINVAL;
872                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
873                                 goto out_err;
874                         }
875                         defcontext = match_strdup(&args[0]);
876                         if (!defcontext) {
877                                 rc = -ENOMEM;
878                                 goto out_err;
879                         }
880                         break;
881                 case Opt_labelsupport:
882                         break;
883                 default:
884                         rc = -EINVAL;
885                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
886                         goto out_err;
887
888                 }
889         }
890
891         rc = -ENOMEM;
892         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
893         if (!opts->mnt_opts)
894                 goto out_err;
895
896         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
897         if (!opts->mnt_opts_flags) {
898                 kfree(opts->mnt_opts);
899                 goto out_err;
900         }
901
902         if (fscontext) {
903                 opts->mnt_opts[num_mnt_opts] = fscontext;
904                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
905         }
906         if (context) {
907                 opts->mnt_opts[num_mnt_opts] = context;
908                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
909         }
910         if (rootcontext) {
911                 opts->mnt_opts[num_mnt_opts] = rootcontext;
912                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
913         }
914         if (defcontext) {
915                 opts->mnt_opts[num_mnt_opts] = defcontext;
916                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
917         }
918
919         opts->num_mnt_opts = num_mnt_opts;
920         return 0;
921
922 out_err:
923         kfree(context);
924         kfree(defcontext);
925         kfree(fscontext);
926         kfree(rootcontext);
927         return rc;
928 }
929 /*
930  * string mount options parsing and call set the sbsec
931  */
932 static int superblock_doinit(struct super_block *sb, void *data)
933 {
934         int rc = 0;
935         char *options = data;
936         struct security_mnt_opts opts;
937
938         security_init_mnt_opts(&opts);
939
940         if (!data)
941                 goto out;
942
943         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
944
945         rc = selinux_parse_opts_str(options, &opts);
946         if (rc)
947                 goto out_err;
948
949 out:
950         rc = selinux_set_mnt_opts(sb, &opts);
951
952 out_err:
953         security_free_mnt_opts(&opts);
954         return rc;
955 }
956
957 static void selinux_write_opts(struct seq_file *m,
958                                struct security_mnt_opts *opts)
959 {
960         int i;
961         char *prefix;
962
963         for (i = 0; i < opts->num_mnt_opts; i++) {
964                 char *has_comma;
965
966                 if (opts->mnt_opts[i])
967                         has_comma = strchr(opts->mnt_opts[i], ',');
968                 else
969                         has_comma = NULL;
970
971                 switch (opts->mnt_opts_flags[i]) {
972                 case CONTEXT_MNT:
973                         prefix = CONTEXT_STR;
974                         break;
975                 case FSCONTEXT_MNT:
976                         prefix = FSCONTEXT_STR;
977                         break;
978                 case ROOTCONTEXT_MNT:
979                         prefix = ROOTCONTEXT_STR;
980                         break;
981                 case DEFCONTEXT_MNT:
982                         prefix = DEFCONTEXT_STR;
983                         break;
984                 case SE_SBLABELSUPP:
985                         seq_putc(m, ',');
986                         seq_puts(m, LABELSUPP_STR);
987                         continue;
988                 default:
989                         BUG();
990                 };
991                 /* we need a comma before each option */
992                 seq_putc(m, ',');
993                 seq_puts(m, prefix);
994                 if (has_comma)
995                         seq_putc(m, '\"');
996                 seq_puts(m, opts->mnt_opts[i]);
997                 if (has_comma)
998                         seq_putc(m, '\"');
999         }
1000 }
1001
1002 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1003 {
1004         struct security_mnt_opts opts;
1005         int rc;
1006
1007         rc = selinux_get_mnt_opts(sb, &opts);
1008         if (rc) {
1009                 /* before policy load we may get EINVAL, don't show anything */
1010                 if (rc == -EINVAL)
1011                         rc = 0;
1012                 return rc;
1013         }
1014
1015         selinux_write_opts(m, &opts);
1016
1017         security_free_mnt_opts(&opts);
1018
1019         return rc;
1020 }
1021
1022 static inline u16 inode_mode_to_security_class(umode_t mode)
1023 {
1024         switch (mode & S_IFMT) {
1025         case S_IFSOCK:
1026                 return SECCLASS_SOCK_FILE;
1027         case S_IFLNK:
1028                 return SECCLASS_LNK_FILE;
1029         case S_IFREG:
1030                 return SECCLASS_FILE;
1031         case S_IFBLK:
1032                 return SECCLASS_BLK_FILE;
1033         case S_IFDIR:
1034                 return SECCLASS_DIR;
1035         case S_IFCHR:
1036                 return SECCLASS_CHR_FILE;
1037         case S_IFIFO:
1038                 return SECCLASS_FIFO_FILE;
1039
1040         }
1041
1042         return SECCLASS_FILE;
1043 }
1044
1045 static inline int default_protocol_stream(int protocol)
1046 {
1047         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1048 }
1049
1050 static inline int default_protocol_dgram(int protocol)
1051 {
1052         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1053 }
1054
1055 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1056 {
1057         switch (family) {
1058         case PF_UNIX:
1059                 switch (type) {
1060                 case SOCK_STREAM:
1061                 case SOCK_SEQPACKET:
1062                         return SECCLASS_UNIX_STREAM_SOCKET;
1063                 case SOCK_DGRAM:
1064                         return SECCLASS_UNIX_DGRAM_SOCKET;
1065                 }
1066                 break;
1067         case PF_INET:
1068         case PF_INET6:
1069                 switch (type) {
1070                 case SOCK_STREAM:
1071                         if (default_protocol_stream(protocol))
1072                                 return SECCLASS_TCP_SOCKET;
1073                         else
1074                                 return SECCLASS_RAWIP_SOCKET;
1075                 case SOCK_DGRAM:
1076                         if (default_protocol_dgram(protocol))
1077                                 return SECCLASS_UDP_SOCKET;
1078                         else
1079                                 return SECCLASS_RAWIP_SOCKET;
1080                 case SOCK_DCCP:
1081                         return SECCLASS_DCCP_SOCKET;
1082                 default:
1083                         return SECCLASS_RAWIP_SOCKET;
1084                 }
1085                 break;
1086         case PF_NETLINK:
1087                 switch (protocol) {
1088                 case NETLINK_ROUTE:
1089                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1090                 case NETLINK_FIREWALL:
1091                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1092                 case NETLINK_INET_DIAG:
1093                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1094                 case NETLINK_NFLOG:
1095                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1096                 case NETLINK_XFRM:
1097                         return SECCLASS_NETLINK_XFRM_SOCKET;
1098                 case NETLINK_SELINUX:
1099                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1100                 case NETLINK_AUDIT:
1101                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1102                 case NETLINK_IP6_FW:
1103                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1104                 case NETLINK_DNRTMSG:
1105                         return SECCLASS_NETLINK_DNRT_SOCKET;
1106                 case NETLINK_KOBJECT_UEVENT:
1107                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1108                 default:
1109                         return SECCLASS_NETLINK_SOCKET;
1110                 }
1111         case PF_PACKET:
1112                 return SECCLASS_PACKET_SOCKET;
1113         case PF_KEY:
1114                 return SECCLASS_KEY_SOCKET;
1115         case PF_APPLETALK:
1116                 return SECCLASS_APPLETALK_SOCKET;
1117         }
1118
1119         return SECCLASS_SOCKET;
1120 }
1121
1122 #ifdef CONFIG_PROC_FS
1123 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1124                                 u16 tclass,
1125                                 u32 *sid)
1126 {
1127         int buflen, rc;
1128         char *buffer, *path, *end;
1129
1130         buffer = (char *)__get_free_page(GFP_KERNEL);
1131         if (!buffer)
1132                 return -ENOMEM;
1133
1134         buflen = PAGE_SIZE;
1135         end = buffer+buflen;
1136         *--end = '\0';
1137         buflen--;
1138         path = end-1;
1139         *path = '/';
1140         while (de && de != de->parent) {
1141                 buflen -= de->namelen + 1;
1142                 if (buflen < 0)
1143                         break;
1144                 end -= de->namelen;
1145                 memcpy(end, de->name, de->namelen);
1146                 *--end = '/';
1147                 path = end;
1148                 de = de->parent;
1149         }
1150         rc = security_genfs_sid("proc", path, tclass, sid);
1151         free_page((unsigned long)buffer);
1152         return rc;
1153 }
1154 #else
1155 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1156                                 u16 tclass,
1157                                 u32 *sid)
1158 {
1159         return -EINVAL;
1160 }
1161 #endif
1162
1163 /* The inode's security attributes must be initialized before first use. */
1164 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165 {
1166         struct superblock_security_struct *sbsec = NULL;
1167         struct inode_security_struct *isec = inode->i_security;
1168         u32 sid;
1169         struct dentry *dentry;
1170 #define INITCONTEXTLEN 255
1171         char *context = NULL;
1172         unsigned len = 0;
1173         int rc = 0;
1174
1175         if (isec->initialized)
1176                 goto out;
1177
1178         mutex_lock(&isec->lock);
1179         if (isec->initialized)
1180                 goto out_unlock;
1181
1182         sbsec = inode->i_sb->s_security;
1183         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184                 /* Defer initialization until selinux_complete_init,
1185                    after the initial policy is loaded and the security
1186                    server is ready to handle calls. */
1187                 spin_lock(&sbsec->isec_lock);
1188                 if (list_empty(&isec->list))
1189                         list_add(&isec->list, &sbsec->isec_head);
1190                 spin_unlock(&sbsec->isec_lock);
1191                 goto out_unlock;
1192         }
1193
1194         switch (sbsec->behavior) {
1195         case SECURITY_FS_USE_XATTR:
1196                 if (!inode->i_op->getxattr) {
1197                         isec->sid = sbsec->def_sid;
1198                         break;
1199                 }
1200
1201                 /* Need a dentry, since the xattr API requires one.
1202                    Life would be simpler if we could just pass the inode. */
1203                 if (opt_dentry) {
1204                         /* Called from d_instantiate or d_splice_alias. */
1205                         dentry = dget(opt_dentry);
1206                 } else {
1207                         /* Called from selinux_complete_init, try to find a dentry. */
1208                         dentry = d_find_alias(inode);
1209                 }
1210                 if (!dentry) {
1211                         /*
1212                          * this is can be hit on boot when a file is accessed
1213                          * before the policy is loaded.  When we load policy we
1214                          * may find inodes that have no dentry on the
1215                          * sbsec->isec_head list.  No reason to complain as these
1216                          * will get fixed up the next time we go through
1217                          * inode_doinit with a dentry, before these inodes could
1218                          * be used again by userspace.
1219                          */
1220                         goto out_unlock;
1221                 }
1222
1223                 len = INITCONTEXTLEN;
1224                 context = kmalloc(len+1, GFP_NOFS);
1225                 if (!context) {
1226                         rc = -ENOMEM;
1227                         dput(dentry);
1228                         goto out_unlock;
1229                 }
1230                 context[len] = '\0';
1231                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232                                            context, len);
1233                 if (rc == -ERANGE) {
1234                         kfree(context);
1235
1236                         /* Need a larger buffer.  Query for the right size. */
1237                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238                                                    NULL, 0);
1239                         if (rc < 0) {
1240                                 dput(dentry);
1241                                 goto out_unlock;
1242                         }
1243                         len = rc;
1244                         context = kmalloc(len+1, GFP_NOFS);
1245                         if (!context) {
1246                                 rc = -ENOMEM;
1247                                 dput(dentry);
1248                                 goto out_unlock;
1249                         }
1250                         context[len] = '\0';
1251                         rc = inode->i_op->getxattr(dentry,
1252                                                    XATTR_NAME_SELINUX,
1253                                                    context, len);
1254                 }
1255                 dput(dentry);
1256                 if (rc < 0) {
1257                         if (rc != -ENODATA) {
1258                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1259                                        "%d for dev=%s ino=%ld\n", __func__,
1260                                        -rc, inode->i_sb->s_id, inode->i_ino);
1261                                 kfree(context);
1262                                 goto out_unlock;
1263                         }
1264                         /* Map ENODATA to the default file SID */
1265                         sid = sbsec->def_sid;
1266                         rc = 0;
1267                 } else {
1268                         rc = security_context_to_sid_default(context, rc, &sid,
1269                                                              sbsec->def_sid,
1270                                                              GFP_NOFS);
1271                         if (rc) {
1272                                 char *dev = inode->i_sb->s_id;
1273                                 unsigned long ino = inode->i_ino;
1274
1275                                 if (rc == -EINVAL) {
1276                                         if (printk_ratelimit())
1277                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1279                                                         "filesystem in question.\n", ino, dev, context);
1280                                 } else {
1281                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1282                                                "returned %d for dev=%s ino=%ld\n",
1283                                                __func__, context, -rc, dev, ino);
1284                                 }
1285                                 kfree(context);
1286                                 /* Leave with the unlabeled SID */
1287                                 rc = 0;
1288                                 break;
1289                         }
1290                 }
1291                 kfree(context);
1292                 isec->sid = sid;
1293                 break;
1294         case SECURITY_FS_USE_TASK:
1295                 isec->sid = isec->task_sid;
1296                 break;
1297         case SECURITY_FS_USE_TRANS:
1298                 /* Default to the fs SID. */
1299                 isec->sid = sbsec->sid;
1300
1301                 /* Try to obtain a transition SID. */
1302                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303                 rc = security_transition_sid(isec->task_sid,
1304                                              sbsec->sid,
1305                                              isec->sclass,
1306                                              &sid);
1307                 if (rc)
1308                         goto out_unlock;
1309                 isec->sid = sid;
1310                 break;
1311         case SECURITY_FS_USE_MNTPOINT:
1312                 isec->sid = sbsec->mntpoint_sid;
1313                 break;
1314         default:
1315                 /* Default to the fs superblock SID. */
1316                 isec->sid = sbsec->sid;
1317
1318                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1319                         struct proc_inode *proci = PROC_I(inode);
1320                         if (proci->pde) {
1321                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1322                                 rc = selinux_proc_get_sid(proci->pde,
1323                                                           isec->sclass,
1324                                                           &sid);
1325                                 if (rc)
1326                                         goto out_unlock;
1327                                 isec->sid = sid;
1328                         }
1329                 }
1330                 break;
1331         }
1332
1333         isec->initialized = 1;
1334
1335 out_unlock:
1336         mutex_unlock(&isec->lock);
1337 out:
1338         if (isec->sclass == SECCLASS_FILE)
1339                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1340         return rc;
1341 }
1342
1343 /* Convert a Linux signal to an access vector. */
1344 static inline u32 signal_to_av(int sig)
1345 {
1346         u32 perm = 0;
1347
1348         switch (sig) {
1349         case SIGCHLD:
1350                 /* Commonly granted from child to parent. */
1351                 perm = PROCESS__SIGCHLD;
1352                 break;
1353         case SIGKILL:
1354                 /* Cannot be caught or ignored */
1355                 perm = PROCESS__SIGKILL;
1356                 break;
1357         case SIGSTOP:
1358                 /* Cannot be caught or ignored */
1359                 perm = PROCESS__SIGSTOP;
1360                 break;
1361         default:
1362                 /* All other signals. */
1363                 perm = PROCESS__SIGNAL;
1364                 break;
1365         }
1366
1367         return perm;
1368 }
1369
1370 /*
1371  * Check permission between a pair of credentials
1372  * fork check, ptrace check, etc.
1373  */
1374 static int cred_has_perm(const struct cred *actor,
1375                          const struct cred *target,
1376                          u32 perms)
1377 {
1378         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1379
1380         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1381 }
1382
1383 /*
1384  * Check permission between a pair of tasks, e.g. signal checks,
1385  * fork check, ptrace check, etc.
1386  * tsk1 is the actor and tsk2 is the target
1387  * - this uses the default subjective creds of tsk1
1388  */
1389 static int task_has_perm(const struct task_struct *tsk1,
1390                          const struct task_struct *tsk2,
1391                          u32 perms)
1392 {
1393         const struct task_security_struct *__tsec1, *__tsec2;
1394         u32 sid1, sid2;
1395
1396         rcu_read_lock();
1397         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1398         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1399         rcu_read_unlock();
1400         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1401 }
1402
1403 /*
1404  * Check permission between current and another task, e.g. signal checks,
1405  * fork check, ptrace check, etc.
1406  * current is the actor and tsk2 is the target
1407  * - this uses current's subjective creds
1408  */
1409 static int current_has_perm(const struct task_struct *tsk,
1410                             u32 perms)
1411 {
1412         u32 sid, tsid;
1413
1414         sid = current_sid();
1415         tsid = task_sid(tsk);
1416         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1417 }
1418
1419 #if CAP_LAST_CAP > 63
1420 #error Fix SELinux to handle capabilities > 63.
1421 #endif
1422
1423 /* Check whether a task is allowed to use a capability. */
1424 static int task_has_capability(struct task_struct *tsk,
1425                                const struct cred *cred,
1426                                int cap, int audit)
1427 {
1428         struct common_audit_data ad;
1429         struct av_decision avd;
1430         u16 sclass;
1431         u32 sid = cred_sid(cred);
1432         u32 av = CAP_TO_MASK(cap);
1433         int rc;
1434
1435         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1436         ad.tsk = tsk;
1437         ad.u.cap = cap;
1438
1439         switch (CAP_TO_INDEX(cap)) {
1440         case 0:
1441                 sclass = SECCLASS_CAPABILITY;
1442                 break;
1443         case 1:
1444                 sclass = SECCLASS_CAPABILITY2;
1445                 break;
1446         default:
1447                 printk(KERN_ERR
1448                        "SELinux:  out of range capability %d\n", cap);
1449                 BUG();
1450         }
1451
1452         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1453         if (audit == SECURITY_CAP_AUDIT)
1454                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1455         return rc;
1456 }
1457
1458 /* Check whether a task is allowed to use a system operation. */
1459 static int task_has_system(struct task_struct *tsk,
1460                            u32 perms)
1461 {
1462         u32 sid = task_sid(tsk);
1463
1464         return avc_has_perm(sid, SECINITSID_KERNEL,
1465                             SECCLASS_SYSTEM, perms, NULL);
1466 }
1467
1468 /* Check whether a task has a particular permission to an inode.
1469    The 'adp' parameter is optional and allows other audit
1470    data to be passed (e.g. the dentry). */
1471 static int inode_has_perm(const struct cred *cred,
1472                           struct inode *inode,
1473                           u32 perms,
1474                           struct common_audit_data *adp)
1475 {
1476         struct inode_security_struct *isec;
1477         struct common_audit_data ad;
1478         u32 sid;
1479
1480         validate_creds(cred);
1481
1482         if (unlikely(IS_PRIVATE(inode)))
1483                 return 0;
1484
1485         sid = cred_sid(cred);
1486         isec = inode->i_security;
1487
1488         if (!adp) {
1489                 adp = &ad;
1490                 COMMON_AUDIT_DATA_INIT(&ad, FS);
1491                 ad.u.fs.inode = inode;
1492         }
1493
1494         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1495 }
1496
1497 /* Same as inode_has_perm, but pass explicit audit data containing
1498    the dentry to help the auditing code to more easily generate the
1499    pathname if needed. */
1500 static inline int dentry_has_perm(const struct cred *cred,
1501                                   struct vfsmount *mnt,
1502                                   struct dentry *dentry,
1503                                   u32 av)
1504 {
1505         struct inode *inode = dentry->d_inode;
1506         struct common_audit_data ad;
1507
1508         COMMON_AUDIT_DATA_INIT(&ad, FS);
1509         ad.u.fs.path.mnt = mnt;
1510         ad.u.fs.path.dentry = dentry;
1511         return inode_has_perm(cred, inode, av, &ad);
1512 }
1513
1514 /* Check whether a task can use an open file descriptor to
1515    access an inode in a given way.  Check access to the
1516    descriptor itself, and then use dentry_has_perm to
1517    check a particular permission to the file.
1518    Access to the descriptor is implicitly granted if it
1519    has the same SID as the process.  If av is zero, then
1520    access to the file is not checked, e.g. for cases
1521    where only the descriptor is affected like seek. */
1522 static int file_has_perm(const struct cred *cred,
1523                          struct file *file,
1524                          u32 av)
1525 {
1526         struct file_security_struct *fsec = file->f_security;
1527         struct inode *inode = file->f_path.dentry->d_inode;
1528         struct common_audit_data ad;
1529         u32 sid = cred_sid(cred);
1530         int rc;
1531
1532         COMMON_AUDIT_DATA_INIT(&ad, FS);
1533         ad.u.fs.path = file->f_path;
1534
1535         if (sid != fsec->sid) {
1536                 rc = avc_has_perm(sid, fsec->sid,
1537                                   SECCLASS_FD,
1538                                   FD__USE,
1539                                   &ad);
1540                 if (rc)
1541                         goto out;
1542         }
1543
1544         /* av is zero if only checking access to the descriptor. */
1545         rc = 0;
1546         if (av)
1547                 rc = inode_has_perm(cred, inode, av, &ad);
1548
1549 out:
1550         return rc;
1551 }
1552
1553 /* Check whether a task can create a file. */
1554 static int may_create(struct inode *dir,
1555                       struct dentry *dentry,
1556                       u16 tclass)
1557 {
1558         const struct task_security_struct *tsec = current_security();
1559         struct inode_security_struct *dsec;
1560         struct superblock_security_struct *sbsec;
1561         u32 sid, newsid;
1562         struct common_audit_data ad;
1563         int rc;
1564
1565         dsec = dir->i_security;
1566         sbsec = dir->i_sb->s_security;
1567
1568         sid = tsec->sid;
1569         newsid = tsec->create_sid;
1570
1571         COMMON_AUDIT_DATA_INIT(&ad, FS);
1572         ad.u.fs.path.dentry = dentry;
1573
1574         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1575                           DIR__ADD_NAME | DIR__SEARCH,
1576                           &ad);
1577         if (rc)
1578                 return rc;
1579
1580         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1581                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1582                 if (rc)
1583                         return rc;
1584         }
1585
1586         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1587         if (rc)
1588                 return rc;
1589
1590         return avc_has_perm(newsid, sbsec->sid,
1591                             SECCLASS_FILESYSTEM,
1592                             FILESYSTEM__ASSOCIATE, &ad);
1593 }
1594
1595 /* Check whether a task can create a key. */
1596 static int may_create_key(u32 ksid,
1597                           struct task_struct *ctx)
1598 {
1599         u32 sid = task_sid(ctx);
1600
1601         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1602 }
1603
1604 #define MAY_LINK        0
1605 #define MAY_UNLINK      1
1606 #define MAY_RMDIR       2
1607
1608 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1609 static int may_link(struct inode *dir,
1610                     struct dentry *dentry,
1611                     int kind)
1612
1613 {
1614         struct inode_security_struct *dsec, *isec;
1615         struct common_audit_data ad;
1616         u32 sid = current_sid();
1617         u32 av;
1618         int rc;
1619
1620         dsec = dir->i_security;
1621         isec = dentry->d_inode->i_security;
1622
1623         COMMON_AUDIT_DATA_INIT(&ad, FS);
1624         ad.u.fs.path.dentry = dentry;
1625
1626         av = DIR__SEARCH;
1627         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1628         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1629         if (rc)
1630                 return rc;
1631
1632         switch (kind) {
1633         case MAY_LINK:
1634                 av = FILE__LINK;
1635                 break;
1636         case MAY_UNLINK:
1637                 av = FILE__UNLINK;
1638                 break;
1639         case MAY_RMDIR:
1640                 av = DIR__RMDIR;
1641                 break;
1642         default:
1643                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1644                         __func__, kind);
1645                 return 0;
1646         }
1647
1648         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1649         return rc;
1650 }
1651
1652 static inline int may_rename(struct inode *old_dir,
1653                              struct dentry *old_dentry,
1654                              struct inode *new_dir,
1655                              struct dentry *new_dentry)
1656 {
1657         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1658         struct common_audit_data ad;
1659         u32 sid = current_sid();
1660         u32 av;
1661         int old_is_dir, new_is_dir;
1662         int rc;
1663
1664         old_dsec = old_dir->i_security;
1665         old_isec = old_dentry->d_inode->i_security;
1666         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1667         new_dsec = new_dir->i_security;
1668
1669         COMMON_AUDIT_DATA_INIT(&ad, FS);
1670
1671         ad.u.fs.path.dentry = old_dentry;
1672         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1673                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1674         if (rc)
1675                 return rc;
1676         rc = avc_has_perm(sid, old_isec->sid,
1677                           old_isec->sclass, FILE__RENAME, &ad);
1678         if (rc)
1679                 return rc;
1680         if (old_is_dir && new_dir != old_dir) {
1681                 rc = avc_has_perm(sid, old_isec->sid,
1682                                   old_isec->sclass, DIR__REPARENT, &ad);
1683                 if (rc)
1684                         return rc;
1685         }
1686
1687         ad.u.fs.path.dentry = new_dentry;
1688         av = DIR__ADD_NAME | DIR__SEARCH;
1689         if (new_dentry->d_inode)
1690                 av |= DIR__REMOVE_NAME;
1691         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1692         if (rc)
1693                 return rc;
1694         if (new_dentry->d_inode) {
1695                 new_isec = new_dentry->d_inode->i_security;
1696                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1697                 rc = avc_has_perm(sid, new_isec->sid,
1698                                   new_isec->sclass,
1699                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1700                 if (rc)
1701                         return rc;
1702         }
1703
1704         return 0;
1705 }
1706
1707 /* Check whether a task can perform a filesystem operation. */
1708 static int superblock_has_perm(const struct cred *cred,
1709                                struct super_block *sb,
1710                                u32 perms,
1711                                struct common_audit_data *ad)
1712 {
1713         struct superblock_security_struct *sbsec;
1714         u32 sid = cred_sid(cred);
1715
1716         sbsec = sb->s_security;
1717         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1718 }
1719
1720 /* Convert a Linux mode and permission mask to an access vector. */
1721 static inline u32 file_mask_to_av(int mode, int mask)
1722 {
1723         u32 av = 0;
1724
1725         if ((mode & S_IFMT) != S_IFDIR) {
1726                 if (mask & MAY_EXEC)
1727                         av |= FILE__EXECUTE;
1728                 if (mask & MAY_READ)
1729                         av |= FILE__READ;
1730
1731                 if (mask & MAY_APPEND)
1732                         av |= FILE__APPEND;
1733                 else if (mask & MAY_WRITE)
1734                         av |= FILE__WRITE;
1735
1736         } else {
1737                 if (mask & MAY_EXEC)
1738                         av |= DIR__SEARCH;
1739                 if (mask & MAY_WRITE)
1740                         av |= DIR__WRITE;
1741                 if (mask & MAY_READ)
1742                         av |= DIR__READ;
1743         }
1744
1745         return av;
1746 }
1747
1748 /* Convert a Linux file to an access vector. */
1749 static inline u32 file_to_av(struct file *file)
1750 {
1751         u32 av = 0;
1752
1753         if (file->f_mode & FMODE_READ)
1754                 av |= FILE__READ;
1755         if (file->f_mode & FMODE_WRITE) {
1756                 if (file->f_flags & O_APPEND)
1757                         av |= FILE__APPEND;
1758                 else
1759                         av |= FILE__WRITE;
1760         }
1761         if (!av) {
1762                 /*
1763                  * Special file opened with flags 3 for ioctl-only use.
1764                  */
1765                 av = FILE__IOCTL;
1766         }
1767
1768         return av;
1769 }
1770
1771 /*
1772  * Convert a file to an access vector and include the correct open
1773  * open permission.
1774  */
1775 static inline u32 open_file_to_av(struct file *file)
1776 {
1777         u32 av = file_to_av(file);
1778
1779         if (selinux_policycap_openperm)
1780                 av |= FILE__OPEN;
1781
1782         return av;
1783 }
1784
1785 /* Hook functions begin here. */
1786
1787 static int selinux_ptrace_access_check(struct task_struct *child,
1788                                      unsigned int mode)
1789 {
1790         int rc;
1791
1792         rc = cap_ptrace_access_check(child, mode);
1793         if (rc)
1794                 return rc;
1795
1796         if (mode == PTRACE_MODE_READ) {
1797                 u32 sid = current_sid();
1798                 u32 csid = task_sid(child);
1799                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1800         }
1801
1802         return current_has_perm(child, PROCESS__PTRACE);
1803 }
1804
1805 static int selinux_ptrace_traceme(struct task_struct *parent)
1806 {
1807         int rc;
1808
1809         rc = cap_ptrace_traceme(parent);
1810         if (rc)
1811                 return rc;
1812
1813         return task_has_perm(parent, current, PROCESS__PTRACE);
1814 }
1815
1816 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1817                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1818 {
1819         int error;
1820
1821         error = current_has_perm(target, PROCESS__GETCAP);
1822         if (error)
1823                 return error;
1824
1825         return cap_capget(target, effective, inheritable, permitted);
1826 }
1827
1828 static int selinux_capset(struct cred *new, const struct cred *old,
1829                           const kernel_cap_t *effective,
1830                           const kernel_cap_t *inheritable,
1831                           const kernel_cap_t *permitted)
1832 {
1833         int error;
1834
1835         error = cap_capset(new, old,
1836                                       effective, inheritable, permitted);
1837         if (error)
1838                 return error;
1839
1840         return cred_has_perm(old, new, PROCESS__SETCAP);
1841 }
1842
1843 /*
1844  * (This comment used to live with the selinux_task_setuid hook,
1845  * which was removed).
1846  *
1847  * Since setuid only affects the current process, and since the SELinux
1848  * controls are not based on the Linux identity attributes, SELinux does not
1849  * need to control this operation.  However, SELinux does control the use of
1850  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1851  */
1852
1853 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1854                            int cap, int audit)
1855 {
1856         int rc;
1857
1858         rc = cap_capable(tsk, cred, cap, audit);
1859         if (rc)
1860                 return rc;
1861
1862         return task_has_capability(tsk, cred, cap, audit);
1863 }
1864
1865 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1866 {
1867         int buflen, rc;
1868         char *buffer, *path, *end;
1869
1870         rc = -ENOMEM;
1871         buffer = (char *)__get_free_page(GFP_KERNEL);
1872         if (!buffer)
1873                 goto out;
1874
1875         buflen = PAGE_SIZE;
1876         end = buffer+buflen;
1877         *--end = '\0';
1878         buflen--;
1879         path = end-1;
1880         *path = '/';
1881         while (table) {
1882                 const char *name = table->procname;
1883                 size_t namelen = strlen(name);
1884                 buflen -= namelen + 1;
1885                 if (buflen < 0)
1886                         goto out_free;
1887                 end -= namelen;
1888                 memcpy(end, name, namelen);
1889                 *--end = '/';
1890                 path = end;
1891                 table = table->parent;
1892         }
1893         buflen -= 4;
1894         if (buflen < 0)
1895                 goto out_free;
1896         end -= 4;
1897         memcpy(end, "/sys", 4);
1898         path = end;
1899         rc = security_genfs_sid("proc", path, tclass, sid);
1900 out_free:
1901         free_page((unsigned long)buffer);
1902 out:
1903         return rc;
1904 }
1905
1906 static int selinux_sysctl(ctl_table *table, int op)
1907 {
1908         int error = 0;
1909         u32 av;
1910         u32 tsid, sid;
1911         int rc;
1912
1913         sid = current_sid();
1914
1915         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1916                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1917         if (rc) {
1918                 /* Default to the well-defined sysctl SID. */
1919                 tsid = SECINITSID_SYSCTL;
1920         }
1921
1922         /* The op values are "defined" in sysctl.c, thereby creating
1923          * a bad coupling between this module and sysctl.c */
1924         if (op == 001) {
1925                 error = avc_has_perm(sid, tsid,
1926                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1927         } else {
1928                 av = 0;
1929                 if (op & 004)
1930                         av |= FILE__READ;
1931                 if (op & 002)
1932                         av |= FILE__WRITE;
1933                 if (av)
1934                         error = avc_has_perm(sid, tsid,
1935                                              SECCLASS_FILE, av, NULL);
1936         }
1937
1938         return error;
1939 }
1940
1941 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1942 {
1943         const struct cred *cred = current_cred();
1944         int rc = 0;
1945
1946         if (!sb)
1947                 return 0;
1948
1949         switch (cmds) {
1950         case Q_SYNC:
1951         case Q_QUOTAON:
1952         case Q_QUOTAOFF:
1953         case Q_SETINFO:
1954         case Q_SETQUOTA:
1955                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1956                 break;
1957         case Q_GETFMT:
1958         case Q_GETINFO:
1959         case Q_GETQUOTA:
1960                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1961                 break;
1962         default:
1963                 rc = 0;  /* let the kernel handle invalid cmds */
1964                 break;
1965         }
1966         return rc;
1967 }
1968
1969 static int selinux_quota_on(struct dentry *dentry)
1970 {
1971         const struct cred *cred = current_cred();
1972
1973         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1974 }
1975
1976 static int selinux_syslog(int type, bool from_file)
1977 {
1978         int rc;
1979
1980         rc = cap_syslog(type, from_file);
1981         if (rc)
1982                 return rc;
1983
1984         switch (type) {
1985         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1986         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1987                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1988                 break;
1989         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1990         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1991         /* Set level of messages printed to console */
1992         case SYSLOG_ACTION_CONSOLE_LEVEL:
1993                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1994                 break;
1995         case SYSLOG_ACTION_CLOSE:       /* Close log */
1996         case SYSLOG_ACTION_OPEN:        /* Open log */
1997         case SYSLOG_ACTION_READ:        /* Read from log */
1998         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1999         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2000         default:
2001                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2002                 break;
2003         }
2004         return rc;
2005 }
2006
2007 /*
2008  * Check that a process has enough memory to allocate a new virtual
2009  * mapping. 0 means there is enough memory for the allocation to
2010  * succeed and -ENOMEM implies there is not.
2011  *
2012  * Do not audit the selinux permission check, as this is applied to all
2013  * processes that allocate mappings.
2014  */
2015 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2016 {
2017         int rc, cap_sys_admin = 0;
2018
2019         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2020                              SECURITY_CAP_NOAUDIT);
2021         if (rc == 0)
2022                 cap_sys_admin = 1;
2023
2024         return __vm_enough_memory(mm, pages, cap_sys_admin);
2025 }
2026
2027 /* binprm security operations */
2028
2029 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2030 {
2031         const struct task_security_struct *old_tsec;
2032         struct task_security_struct *new_tsec;
2033         struct inode_security_struct *isec;
2034         struct common_audit_data ad;
2035         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2036         int rc;
2037
2038         rc = cap_bprm_set_creds(bprm);
2039         if (rc)
2040                 return rc;
2041
2042         /* SELinux context only depends on initial program or script and not
2043          * the script interpreter */
2044         if (bprm->cred_prepared)
2045                 return 0;
2046
2047         old_tsec = current_security();
2048         new_tsec = bprm->cred->security;
2049         isec = inode->i_security;
2050
2051         /* Default to the current task SID. */
2052         new_tsec->sid = old_tsec->sid;
2053         new_tsec->osid = old_tsec->sid;
2054
2055         /* Reset fs, key, and sock SIDs on execve. */
2056         new_tsec->create_sid = 0;
2057         new_tsec->keycreate_sid = 0;
2058         new_tsec->sockcreate_sid = 0;
2059
2060         if (old_tsec->exec_sid) {
2061                 new_tsec->sid = old_tsec->exec_sid;
2062                 /* Reset exec SID on execve. */
2063                 new_tsec->exec_sid = 0;
2064         } else {
2065                 /* Check for a default transition on this program. */
2066                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2067                                              SECCLASS_PROCESS, &new_tsec->sid);
2068                 if (rc)
2069                         return rc;
2070         }
2071
2072         COMMON_AUDIT_DATA_INIT(&ad, FS);
2073         ad.u.fs.path = bprm->file->f_path;
2074
2075         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2076                 new_tsec->sid = old_tsec->sid;
2077
2078         if (new_tsec->sid == old_tsec->sid) {
2079                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2080                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2081                 if (rc)
2082                         return rc;
2083         } else {
2084                 /* Check permissions for the transition. */
2085                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2086                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2087                 if (rc)
2088                         return rc;
2089
2090                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2091                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2092                 if (rc)
2093                         return rc;
2094
2095                 /* Check for shared state */
2096                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2097                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2098                                           SECCLASS_PROCESS, PROCESS__SHARE,
2099                                           NULL);
2100                         if (rc)
2101                                 return -EPERM;
2102                 }
2103
2104                 /* Make sure that anyone attempting to ptrace over a task that
2105                  * changes its SID has the appropriate permit */
2106                 if (bprm->unsafe &
2107                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2108                         struct task_struct *tracer;
2109                         struct task_security_struct *sec;
2110                         u32 ptsid = 0;
2111
2112                         rcu_read_lock();
2113                         tracer = tracehook_tracer_task(current);
2114                         if (likely(tracer != NULL)) {
2115                                 sec = __task_cred(tracer)->security;
2116                                 ptsid = sec->sid;
2117                         }
2118                         rcu_read_unlock();
2119
2120                         if (ptsid != 0) {
2121                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2122                                                   SECCLASS_PROCESS,
2123                                                   PROCESS__PTRACE, NULL);
2124                                 if (rc)
2125                                         return -EPERM;
2126                         }
2127                 }
2128
2129                 /* Clear any possibly unsafe personality bits on exec: */
2130                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2131         }
2132
2133         return 0;
2134 }
2135
2136 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2137 {
2138         const struct task_security_struct *tsec = current_security();
2139         u32 sid, osid;
2140         int atsecure = 0;
2141
2142         sid = tsec->sid;
2143         osid = tsec->osid;
2144
2145         if (osid != sid) {
2146                 /* Enable secure mode for SIDs transitions unless
2147                    the noatsecure permission is granted between
2148                    the two SIDs, i.e. ahp returns 0. */
2149                 atsecure = avc_has_perm(osid, sid,
2150                                         SECCLASS_PROCESS,
2151                                         PROCESS__NOATSECURE, NULL);
2152         }
2153
2154         return (atsecure || cap_bprm_secureexec(bprm));
2155 }
2156
2157 extern struct vfsmount *selinuxfs_mount;
2158 extern struct dentry *selinux_null;
2159
2160 /* Derived from fs/exec.c:flush_old_files. */
2161 static inline void flush_unauthorized_files(const struct cred *cred,
2162                                             struct files_struct *files)
2163 {
2164         struct common_audit_data ad;
2165         struct file *file, *devnull = NULL;
2166         struct tty_struct *tty;
2167         struct fdtable *fdt;
2168         long j = -1;
2169         int drop_tty = 0;
2170
2171         tty = get_current_tty();
2172         if (tty) {
2173                 spin_lock(&tty_files_lock);
2174                 if (!list_empty(&tty->tty_files)) {
2175                         struct inode *inode;
2176
2177                         /* Revalidate access to controlling tty.
2178                            Use inode_has_perm on the tty inode directly rather
2179                            than using file_has_perm, as this particular open
2180                            file may belong to another process and we are only
2181                            interested in the inode-based check here. */
2182                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2183                         inode = file->f_path.dentry->d_inode;
2184                         if (inode_has_perm(cred, inode,
2185                                            FILE__READ | FILE__WRITE, NULL)) {
2186                                 drop_tty = 1;
2187                         }
2188                 }
2189                 spin_unlock(&tty_files_lock);
2190                 tty_kref_put(tty);
2191         }
2192         /* Reset controlling tty. */
2193         if (drop_tty)
2194                 no_tty();
2195
2196         /* Revalidate access to inherited open files. */
2197
2198         COMMON_AUDIT_DATA_INIT(&ad, FS);
2199
2200         spin_lock(&files->file_lock);
2201         for (;;) {
2202                 unsigned long set, i;
2203                 int fd;
2204
2205                 j++;
2206                 i = j * __NFDBITS;
2207                 fdt = files_fdtable(files);
2208                 if (i >= fdt->max_fds)
2209                         break;
2210                 set = fdt->open_fds->fds_bits[j];
2211                 if (!set)
2212                         continue;
2213                 spin_unlock(&files->file_lock);
2214                 for ( ; set ; i++, set >>= 1) {
2215                         if (set & 1) {
2216                                 file = fget(i);
2217                                 if (!file)
2218                                         continue;
2219                                 if (file_has_perm(cred,
2220                                                   file,
2221                                                   file_to_av(file))) {
2222                                         sys_close(i);
2223                                         fd = get_unused_fd();
2224                                         if (fd != i) {
2225                                                 if (fd >= 0)
2226                                                         put_unused_fd(fd);
2227                                                 fput(file);
2228                                                 continue;
2229                                         }
2230                                         if (devnull) {
2231                                                 get_file(devnull);
2232                                         } else {
2233                                                 devnull = dentry_open(
2234                                                         dget(selinux_null),
2235                                                         mntget(selinuxfs_mount),
2236                                                         O_RDWR, cred);
2237                                                 if (IS_ERR(devnull)) {
2238                                                         devnull = NULL;
2239                                                         put_unused_fd(fd);
2240                                                         fput(file);
2241                                                         continue;
2242                                                 }
2243                                         }
2244                                         fd_install(fd, devnull);
2245                                 }
2246                                 fput(file);
2247                         }
2248                 }
2249                 spin_lock(&files->file_lock);
2250
2251         }
2252         spin_unlock(&files->file_lock);
2253 }
2254
2255 /*
2256  * Prepare a process for imminent new credential changes due to exec
2257  */
2258 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2259 {
2260         struct task_security_struct *new_tsec;
2261         struct rlimit *rlim, *initrlim;
2262         int rc, i;
2263
2264         new_tsec = bprm->cred->security;
2265         if (new_tsec->sid == new_tsec->osid)
2266                 return;
2267
2268         /* Close files for which the new task SID is not authorized. */
2269         flush_unauthorized_files(bprm->cred, current->files);
2270
2271         /* Always clear parent death signal on SID transitions. */
2272         current->pdeath_signal = 0;
2273
2274         /* Check whether the new SID can inherit resource limits from the old
2275          * SID.  If not, reset all soft limits to the lower of the current
2276          * task's hard limit and the init task's soft limit.
2277          *
2278          * Note that the setting of hard limits (even to lower them) can be
2279          * controlled by the setrlimit check.  The inclusion of the init task's
2280          * soft limit into the computation is to avoid resetting soft limits
2281          * higher than the default soft limit for cases where the default is
2282          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2283          */
2284         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2285                           PROCESS__RLIMITINH, NULL);
2286         if (rc) {
2287                 /* protect against do_prlimit() */
2288                 task_lock(current);
2289                 for (i = 0; i < RLIM_NLIMITS; i++) {
2290                         rlim = current->signal->rlim + i;
2291                         initrlim = init_task.signal->rlim + i;
2292                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2293                 }
2294                 task_unlock(current);
2295                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2296         }
2297 }
2298
2299 /*
2300  * Clean up the process immediately after the installation of new credentials
2301  * due to exec
2302  */
2303 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2304 {
2305         const struct task_security_struct *tsec = current_security();
2306         struct itimerval itimer;
2307         u32 osid, sid;
2308         int rc, i;
2309
2310         osid = tsec->osid;
2311         sid = tsec->sid;
2312
2313         if (sid == osid)
2314                 return;
2315
2316         /* Check whether the new SID can inherit signal state from the old SID.
2317          * If not, clear itimers to avoid subsequent signal generation and
2318          * flush and unblock signals.
2319          *
2320          * This must occur _after_ the task SID has been updated so that any
2321          * kill done after the flush will be checked against the new SID.
2322          */
2323         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2324         if (rc) {
2325                 memset(&itimer, 0, sizeof itimer);
2326                 for (i = 0; i < 3; i++)
2327                         do_setitimer(i, &itimer, NULL);
2328                 spin_lock_irq(&current->sighand->siglock);
2329                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2330                         __flush_signals(current);
2331                         flush_signal_handlers(current, 1);
2332                         sigemptyset(&current->blocked);
2333                 }
2334                 spin_unlock_irq(&current->sighand->siglock);
2335         }
2336
2337         /* Wake up the parent if it is waiting so that it can recheck
2338          * wait permission to the new task SID. */
2339         read_lock(&tasklist_lock);
2340         __wake_up_parent(current, current->real_parent);
2341         read_unlock(&tasklist_lock);
2342 }
2343
2344 /* superblock security operations */
2345
2346 static int selinux_sb_alloc_security(struct super_block *sb)
2347 {
2348         return superblock_alloc_security(sb);
2349 }
2350
2351 static void selinux_sb_free_security(struct super_block *sb)
2352 {
2353         superblock_free_security(sb);
2354 }
2355
2356 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2357 {
2358         if (plen > olen)
2359                 return 0;
2360
2361         return !memcmp(prefix, option, plen);
2362 }
2363
2364 static inline int selinux_option(char *option, int len)
2365 {
2366         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2367                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2368                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2369                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2370                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2371 }
2372
2373 static inline void take_option(char **to, char *from, int *first, int len)
2374 {
2375         if (!*first) {
2376                 **to = ',';
2377                 *to += 1;
2378         } else
2379                 *first = 0;
2380         memcpy(*to, from, len);
2381         *to += len;
2382 }
2383
2384 static inline void take_selinux_option(char **to, char *from, int *first,
2385                                        int len)
2386 {
2387         int current_size = 0;
2388
2389         if (!*first) {
2390                 **to = '|';
2391                 *to += 1;
2392         } else
2393                 *first = 0;
2394
2395         while (current_size < len) {
2396                 if (*from != '"') {
2397                         **to = *from;
2398                         *to += 1;
2399                 }
2400                 from += 1;
2401                 current_size += 1;
2402         }
2403 }
2404
2405 static int selinux_sb_copy_data(char *orig, char *copy)
2406 {
2407         int fnosec, fsec, rc = 0;
2408         char *in_save, *in_curr, *in_end;
2409         char *sec_curr, *nosec_save, *nosec;
2410         int open_quote = 0;
2411
2412         in_curr = orig;
2413         sec_curr = copy;
2414
2415         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2416         if (!nosec) {
2417                 rc = -ENOMEM;
2418                 goto out;
2419         }
2420
2421         nosec_save = nosec;
2422         fnosec = fsec = 1;
2423         in_save = in_end = orig;
2424
2425         do {
2426                 if (*in_end == '"')
2427                         open_quote = !open_quote;
2428                 if ((*in_end == ',' && open_quote == 0) ||
2429                                 *in_end == '\0') {
2430                         int len = in_end - in_curr;
2431
2432                         if (selinux_option(in_curr, len))
2433                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2434                         else
2435                                 take_option(&nosec, in_curr, &fnosec, len);
2436
2437                         in_curr = in_end + 1;
2438                 }
2439         } while (*in_end++);
2440
2441         strcpy(in_save, nosec_save);
2442         free_page((unsigned long)nosec_save);
2443 out:
2444         return rc;
2445 }
2446
2447 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2448 {
2449         const struct cred *cred = current_cred();
2450         struct common_audit_data ad;
2451         int rc;
2452
2453         rc = superblock_doinit(sb, data);
2454         if (rc)
2455                 return rc;
2456
2457         /* Allow all mounts performed by the kernel */
2458         if (flags & MS_KERNMOUNT)
2459                 return 0;
2460
2461         COMMON_AUDIT_DATA_INIT(&ad, FS);
2462         ad.u.fs.path.dentry = sb->s_root;
2463         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2464 }
2465
2466 static int selinux_sb_statfs(struct dentry *dentry)
2467 {
2468         const struct cred *cred = current_cred();
2469         struct common_audit_data ad;
2470
2471         COMMON_AUDIT_DATA_INIT(&ad, FS);
2472         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2473         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2474 }
2475
2476 static int selinux_mount(char *dev_name,
2477                          struct path *path,
2478                          char *type,
2479                          unsigned long flags,
2480                          void *data)
2481 {
2482         const struct cred *cred = current_cred();
2483
2484         if (flags & MS_REMOUNT)
2485                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2486                                            FILESYSTEM__REMOUNT, NULL);
2487         else
2488                 return dentry_has_perm(cred, path->mnt, path->dentry,
2489                                        FILE__MOUNTON);
2490 }
2491
2492 static int selinux_umount(struct vfsmount *mnt, int flags)
2493 {
2494         const struct cred *cred = current_cred();
2495
2496         return superblock_has_perm(cred, mnt->mnt_sb,
2497                                    FILESYSTEM__UNMOUNT, NULL);
2498 }
2499
2500 /* inode security operations */
2501
2502 static int selinux_inode_alloc_security(struct inode *inode)
2503 {
2504         return inode_alloc_security(inode);
2505 }
2506
2507 static void selinux_inode_free_security(struct inode *inode)
2508 {
2509         inode_free_security(inode);
2510 }
2511
2512 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2513                                        char **name, void **value,
2514                                        size_t *len)
2515 {
2516         const struct task_security_struct *tsec = current_security();
2517         struct inode_security_struct *dsec;
2518         struct superblock_security_struct *sbsec;
2519         u32 sid, newsid, clen;
2520         int rc;
2521         char *namep = NULL, *context;
2522
2523         dsec = dir->i_security;
2524         sbsec = dir->i_sb->s_security;
2525
2526         sid = tsec->sid;
2527         newsid = tsec->create_sid;
2528
2529         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2530                 rc = security_transition_sid(sid, dsec->sid,
2531                                              inode_mode_to_security_class(inode->i_mode),
2532                                              &newsid);
2533                 if (rc) {
2534                         printk(KERN_WARNING "%s:  "
2535                                "security_transition_sid failed, rc=%d (dev=%s "
2536                                "ino=%ld)\n",
2537                                __func__,
2538                                -rc, inode->i_sb->s_id, inode->i_ino);
2539                         return rc;
2540                 }
2541         }
2542
2543         /* Possibly defer initialization to selinux_complete_init. */
2544         if (sbsec->flags & SE_SBINITIALIZED) {
2545                 struct inode_security_struct *isec = inode->i_security;
2546                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2547                 isec->sid = newsid;
2548                 isec->initialized = 1;
2549         }
2550
2551         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2552                 return -EOPNOTSUPP;
2553
2554         if (name) {
2555                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2556                 if (!namep)
2557                         return -ENOMEM;
2558                 *name = namep;
2559         }
2560
2561         if (value && len) {
2562                 rc = security_sid_to_context_force(newsid, &context, &clen);
2563                 if (rc) {
2564                         kfree(namep);
2565                         return rc;
2566                 }
2567                 *value = context;
2568                 *len = clen;
2569         }
2570
2571         return 0;
2572 }
2573
2574 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2575 {
2576         return may_create(dir, dentry, SECCLASS_FILE);
2577 }
2578
2579 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2580 {
2581         return may_link(dir, old_dentry, MAY_LINK);
2582 }
2583
2584 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2585 {
2586         return may_link(dir, dentry, MAY_UNLINK);
2587 }
2588
2589 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2590 {
2591         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2592 }
2593
2594 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2595 {
2596         return may_create(dir, dentry, SECCLASS_DIR);
2597 }
2598
2599 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2600 {
2601         return may_link(dir, dentry, MAY_RMDIR);
2602 }
2603
2604 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2605 {
2606         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2607 }
2608
2609 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2610                                 struct inode *new_inode, struct dentry *new_dentry)
2611 {
2612         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2613 }
2614
2615 static int selinux_inode_readlink(struct dentry *dentry)
2616 {
2617         const struct cred *cred = current_cred();
2618
2619         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2620 }
2621
2622 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2623 {
2624         const struct cred *cred = current_cred();
2625
2626         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2627 }
2628
2629 static int selinux_inode_permission(struct inode *inode, int mask)
2630 {
2631         const struct cred *cred = current_cred();
2632         struct common_audit_data ad;
2633         u32 perms;
2634         bool from_access;
2635
2636         from_access = mask & MAY_ACCESS;
2637         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2638
2639         /* No permission to check.  Existence test. */
2640         if (!mask)
2641                 return 0;
2642
2643         COMMON_AUDIT_DATA_INIT(&ad, FS);
2644         ad.u.fs.inode = inode;
2645
2646         if (from_access)
2647                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2648
2649         perms = file_mask_to_av(inode->i_mode, mask);
2650
2651         return inode_has_perm(cred, inode, perms, &ad);
2652 }
2653
2654 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2655 {
2656         const struct cred *cred = current_cred();
2657         unsigned int ia_valid = iattr->ia_valid;
2658
2659         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2660         if (ia_valid & ATTR_FORCE) {
2661                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2662                               ATTR_FORCE);
2663                 if (!ia_valid)
2664                         return 0;
2665         }
2666
2667         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2668                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2669                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2670
2671         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2672 }
2673
2674 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2675 {
2676         const struct cred *cred = current_cred();
2677
2678         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2679 }
2680
2681 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2682 {
2683         const struct cred *cred = current_cred();
2684
2685         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2686                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2687                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2688                         if (!capable(CAP_SETFCAP))
2689                                 return -EPERM;
2690                 } else if (!capable(CAP_SYS_ADMIN)) {
2691                         /* A different attribute in the security namespace.
2692                            Restrict to administrator. */
2693                         return -EPERM;
2694                 }
2695         }
2696
2697         /* Not an attribute we recognize, so just check the
2698            ordinary setattr permission. */
2699         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2700 }
2701
2702 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2703                                   const void *value, size_t size, int flags)
2704 {
2705         struct inode *inode = dentry->d_inode;
2706         struct inode_security_struct *isec = inode->i_security;
2707         struct superblock_security_struct *sbsec;
2708         struct common_audit_data ad;
2709         u32 newsid, sid = current_sid();
2710         int rc = 0;
2711
2712         if (strcmp(name, XATTR_NAME_SELINUX))
2713                 return selinux_inode_setotherxattr(dentry, name);
2714
2715         sbsec = inode->i_sb->s_security;
2716         if (!(sbsec->flags & SE_SBLABELSUPP))
2717                 return -EOPNOTSUPP;
2718
2719         if (!is_owner_or_cap(inode))
2720                 return -EPERM;
2721
2722         COMMON_AUDIT_DATA_INIT(&ad, FS);
2723         ad.u.fs.path.dentry = dentry;
2724
2725         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2726                           FILE__RELABELFROM, &ad);
2727         if (rc)
2728                 return rc;
2729
2730         rc = security_context_to_sid(value, size, &newsid);
2731         if (rc == -EINVAL) {
2732                 if (!capable(CAP_MAC_ADMIN))
2733                         return rc;
2734                 rc = security_context_to_sid_force(value, size, &newsid);
2735         }
2736         if (rc)
2737                 return rc;
2738
2739         rc = avc_has_perm(sid, newsid, isec->sclass,
2740                           FILE__RELABELTO, &ad);
2741         if (rc)
2742                 return rc;
2743
2744         rc = security_validate_transition(isec->sid, newsid, sid,
2745                                           isec->sclass);
2746         if (rc)
2747                 return rc;
2748
2749         return avc_has_perm(newsid,
2750                             sbsec->sid,
2751                             SECCLASS_FILESYSTEM,
2752                             FILESYSTEM__ASSOCIATE,
2753                             &ad);
2754 }
2755
2756 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2757                                         const void *value, size_t size,
2758                                         int flags)
2759 {
2760         struct inode *inode = dentry->d_inode;
2761         struct inode_security_struct *isec = inode->i_security;
2762         u32 newsid;
2763         int rc;
2764
2765         if (strcmp(name, XATTR_NAME_SELINUX)) {
2766                 /* Not an attribute we recognize, so nothing to do. */
2767                 return;
2768         }
2769
2770         rc = security_context_to_sid_force(value, size, &newsid);
2771         if (rc) {
2772                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2773                        "for (%s, %lu), rc=%d\n",
2774                        inode->i_sb->s_id, inode->i_ino, -rc);
2775                 return;
2776         }
2777
2778         isec->sid = newsid;
2779         return;
2780 }
2781
2782 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2783 {
2784         const struct cred *cred = current_cred();
2785
2786         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2787 }
2788
2789 static int selinux_inode_listxattr(struct dentry *dentry)
2790 {
2791         const struct cred *cred = current_cred();
2792
2793         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2794 }
2795
2796 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2797 {
2798         if (strcmp(name, XATTR_NAME_SELINUX))
2799                 return selinux_inode_setotherxattr(dentry, name);
2800
2801         /* No one is allowed to remove a SELinux security label.
2802            You can change the label, but all data must be labeled. */
2803         return -EACCES;
2804 }
2805
2806 /*
2807  * Copy the inode security context value to the user.
2808  *
2809  * Permission check is handled by selinux_inode_getxattr hook.
2810  */
2811 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2812 {
2813         u32 size;
2814         int error;
2815         char *context = NULL;
2816         struct inode_security_struct *isec = inode->i_security;
2817
2818         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2819                 return -EOPNOTSUPP;
2820
2821         /*
2822          * If the caller has CAP_MAC_ADMIN, then get the raw context
2823          * value even if it is not defined by current policy; otherwise,
2824          * use the in-core value under current policy.
2825          * Use the non-auditing forms of the permission checks since
2826          * getxattr may be called by unprivileged processes commonly
2827          * and lack of permission just means that we fall back to the
2828          * in-core context value, not a denial.
2829          */
2830         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2831                                 SECURITY_CAP_NOAUDIT);
2832         if (!error)
2833                 error = security_sid_to_context_force(isec->sid, &context,
2834                                                       &size);
2835         else
2836                 error = security_sid_to_context(isec->sid, &context, &size);
2837         if (error)
2838                 return error;
2839         error = size;
2840         if (alloc) {
2841                 *buffer = context;
2842                 goto out_nofree;
2843         }
2844         kfree(context);
2845 out_nofree:
2846         return error;
2847 }
2848
2849 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2850                                      const void *value, size_t size, int flags)
2851 {
2852         struct inode_security_struct *isec = inode->i_security;
2853         u32 newsid;
2854         int rc;
2855
2856         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2857                 return -EOPNOTSUPP;
2858
2859         if (!value || !size)
2860                 return -EACCES;
2861
2862         rc = security_context_to_sid((void *)value, size, &newsid);
2863         if (rc)
2864                 return rc;
2865
2866         isec->sid = newsid;
2867         isec->initialized = 1;
2868         return 0;
2869 }
2870
2871 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2872 {
2873         const int len = sizeof(XATTR_NAME_SELINUX);
2874         if (buffer && len <= buffer_size)
2875                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2876         return len;
2877 }
2878
2879 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2880 {
2881         struct inode_security_struct *isec = inode->i_security;
2882         *secid = isec->sid;
2883 }
2884
2885 /* file security operations */
2886
2887 static int selinux_revalidate_file_permission(struct file *file, int mask)
2888 {
2889         const struct cred *cred = current_cred();
2890         struct inode *inode = file->f_path.dentry->d_inode;
2891
2892         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2893         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2894                 mask |= MAY_APPEND;
2895
2896         return file_has_perm(cred, file,
2897                              file_mask_to_av(inode->i_mode, mask));
2898 }
2899
2900 static int selinux_file_permission(struct file *file, int mask)
2901 {
2902         struct inode *inode = file->f_path.dentry->d_inode;
2903         struct file_security_struct *fsec = file->f_security;
2904         struct inode_security_struct *isec = inode->i_security;
2905         u32 sid = current_sid();
2906
2907         if (!mask)
2908                 /* No permission to check.  Existence test. */
2909                 return 0;
2910
2911         if (sid == fsec->sid && fsec->isid == isec->sid &&
2912             fsec->pseqno == avc_policy_seqno())
2913                 /* No change since dentry_open check. */
2914                 return 0;
2915
2916         return selinux_revalidate_file_permission(file, mask);
2917 }
2918
2919 static int selinux_file_alloc_security(struct file *file)
2920 {
2921         return file_alloc_security(file);
2922 }
2923
2924 static void selinux_file_free_security(struct file *file)
2925 {
2926         file_free_security(file);
2927 }
2928
2929 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2930                               unsigned long arg)
2931 {
2932         const struct cred *cred = current_cred();
2933         u32 av = 0;
2934
2935         if (_IOC_DIR(cmd) & _IOC_WRITE)
2936                 av |= FILE__WRITE;
2937         if (_IOC_DIR(cmd) & _IOC_READ)
2938                 av |= FILE__READ;
2939         if (!av)
2940                 av = FILE__IOCTL;
2941
2942         return file_has_perm(cred, file, av);
2943 }
2944
2945 static int default_noexec;
2946
2947 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2948 {
2949         const struct cred *cred = current_cred();
2950         int rc = 0;
2951
2952         if (default_noexec &&
2953             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2954                 /*
2955                  * We are making executable an anonymous mapping or a
2956                  * private file mapping that will also be writable.
2957                  * This has an additional check.
2958                  */
2959                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
2960                 if (rc)
2961                         goto error;
2962         }
2963
2964         if (file) {
2965                 /* read access is always possible with a mapping */
2966                 u32 av = FILE__READ;
2967
2968                 /* write access only matters if the mapping is shared */
2969                 if (shared && (prot & PROT_WRITE))
2970                         av |= FILE__WRITE;
2971
2972                 if (prot & PROT_EXEC)
2973                         av |= FILE__EXECUTE;
2974
2975                 return file_has_perm(cred, file, av);
2976         }
2977
2978 error:
2979         return rc;
2980 }
2981
2982 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2983                              unsigned long prot, unsigned long flags,
2984                              unsigned long addr, unsigned long addr_only)
2985 {
2986         int rc = 0;
2987         u32 sid = current_sid();
2988
2989         /*
2990          * notice that we are intentionally putting the SELinux check before
2991          * the secondary cap_file_mmap check.  This is such a likely attempt
2992          * at bad behaviour/exploit that we always want to get the AVC, even
2993          * if DAC would have also denied the operation.
2994          */
2995         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
2996                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
2997                                   MEMPROTECT__MMAP_ZERO, NULL);
2998                 if (rc)
2999                         return rc;
3000         }
3001
3002         /* do DAC check on address space usage */
3003         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3004         if (rc || addr_only)
3005                 return rc;
3006
3007         if (selinux_checkreqprot)
3008                 prot = reqprot;
3009
3010         return file_map_prot_check(file, prot,
3011                                    (flags & MAP_TYPE) == MAP_SHARED);
3012 }
3013
3014 static int selinux_file_mprotect(struct vm_area_struct *vma,
3015                                  unsigned long reqprot,
3016                                  unsigned long prot)
3017 {
3018         const struct cred *cred = current_cred();
3019
3020         if (selinux_checkreqprot)
3021                 prot = reqprot;
3022
3023         if (default_noexec &&
3024             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3025                 int rc = 0;
3026                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3027                     vma->vm_end <= vma->vm_mm->brk) {
3028                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3029                 } else if (!vma->vm_file &&
3030                            vma->vm_start <= vma->vm_mm->start_stack &&
3031                            vma->vm_end >= vma->vm_mm->start_stack) {
3032                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3033                 } else if (vma->vm_file && vma->anon_vma) {
3034                         /*
3035                          * We are making executable a file mapping that has
3036                          * had some COW done. Since pages might have been
3037                          * written, check ability to execute the possibly
3038                          * modified content.  This typically should only
3039                          * occur for text relocations.
3040                          */
3041                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3042                 }
3043                 if (rc)
3044                         return rc;
3045         }
3046
3047         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3048 }
3049
3050 static int selinux_file_lock(struct file *file, unsigned int cmd)
3051 {
3052         const struct cred *cred = current_cred();
3053
3054         return file_has_perm(cred, file, FILE__LOCK);
3055 }
3056
3057 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3058                               unsigned long arg)
3059 {
3060         const struct cred *cred = current_cred();
3061         int err = 0;
3062
3063         switch (cmd) {
3064         case F_SETFL:
3065                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3066                         err = -EINVAL;
3067                         break;
3068                 }
3069
3070                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3071                         err = file_has_perm(cred, file, FILE__WRITE);
3072                         break;
3073                 }
3074                 /* fall through */
3075         case F_SETOWN:
3076         case F_SETSIG:
3077         case F_GETFL:
3078         case F_GETOWN:
3079         case F_GETSIG:
3080                 /* Just check FD__USE permission */
3081                 err = file_has_perm(cred, file, 0);
3082                 break;
3083         case F_GETLK:
3084         case F_SETLK:
3085         case F_SETLKW:
3086 #if BITS_PER_LONG == 32
3087         case F_GETLK64:
3088         case F_SETLK64:
3089         case F_SETLKW64:
3090 #endif
3091                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3092                         err = -EINVAL;
3093                         break;
3094                 }
3095                 err = file_has_perm(cred, file, FILE__LOCK);
3096                 break;
3097         }
3098
3099         return err;
3100 }
3101
3102 static int selinux_file_set_fowner(struct file *file)
3103 {
3104         struct file_security_struct *fsec;
3105
3106         fsec = file->f_security;
3107         fsec->fown_sid = current_sid();
3108
3109         return 0;
3110 }
3111
3112 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3113                                        struct fown_struct *fown, int signum)
3114 {
3115         struct file *file;
3116         u32 sid = task_sid(tsk);
3117         u32 perm;
3118         struct file_security_struct *fsec;
3119
3120         /* struct fown_struct is never outside the context of a struct file */
3121         file = container_of(fown, struct file, f_owner);
3122
3123         fsec = file->f_security;
3124
3125         if (!signum)
3126                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3127         else
3128                 perm = signal_to_av(signum);
3129
3130         return avc_has_perm(fsec->fown_sid, sid,
3131                             SECCLASS_PROCESS, perm, NULL);
3132 }
3133
3134 static int selinux_file_receive(struct file *file)
3135 {
3136         const struct cred *cred = current_cred();
3137
3138         return file_has_perm(cred, file, file_to_av(file));
3139 }
3140
3141 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3142 {
3143         struct file_security_struct *fsec;
3144         struct inode *inode;
3145         struct inode_security_struct *isec;
3146
3147         inode = file->f_path.dentry->d_inode;
3148         fsec = file->f_security;
3149         isec = inode->i_security;
3150         /*
3151          * Save inode label and policy sequence number
3152          * at open-time so that selinux_file_permission
3153          * can determine whether revalidation is necessary.
3154          * Task label is already saved in the file security
3155          * struct as its SID.
3156          */
3157         fsec->isid = isec->sid;
3158         fsec->pseqno = avc_policy_seqno();
3159         /*
3160          * Since the inode label or policy seqno may have changed
3161          * between the selinux_inode_permission check and the saving
3162          * of state above, recheck that access is still permitted.
3163          * Otherwise, access might never be revalidated against the
3164          * new inode label or new policy.
3165          * This check is not redundant - do not remove.
3166          */
3167         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3168 }
3169
3170 /* task security operations */
3171
3172 static int selinux_task_create(unsigned long clone_flags)
3173 {
3174         return current_has_perm(current, PROCESS__FORK);
3175 }
3176
3177 /*
3178  * allocate the SELinux part of blank credentials
3179  */
3180 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3181 {
3182         struct task_security_struct *tsec;
3183
3184         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3185         if (!tsec)
3186                 return -ENOMEM;
3187
3188         cred->security = tsec;
3189         return 0;
3190 }
3191
3192 /*
3193  * detach and free the LSM part of a set of credentials
3194  */
3195 static void selinux_cred_free(struct cred *cred)
3196 {
3197         struct task_security_struct *tsec = cred->security;
3198
3199         BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3200         cred->security = (void *) 0x7UL;
3201         kfree(tsec);
3202 }
3203
3204 /*
3205  * prepare a new set of credentials for modification
3206  */
3207 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3208                                 gfp_t gfp)
3209 {
3210         const struct task_security_struct *old_tsec;
3211         struct task_security_struct *tsec;
3212
3213         old_tsec = old->security;
3214
3215         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3216         if (!tsec)
3217                 return -ENOMEM;
3218
3219         new->security = tsec;
3220         return 0;
3221 }
3222
3223 /*
3224  * transfer the SELinux data to a blank set of creds
3225  */
3226 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3227 {
3228         const struct task_security_struct *old_tsec = old->security;
3229         struct task_security_struct *tsec = new->security;
3230
3231         *tsec = *old_tsec;
3232 }
3233
3234 /*
3235  * set the security data for a kernel service
3236  * - all the creation contexts are set to unlabelled
3237  */
3238 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3239 {
3240         struct task_security_struct *tsec = new->security;
3241         u32 sid = current_sid();
3242         int ret;
3243
3244         ret = avc_has_perm(sid, secid,
3245                            SECCLASS_KERNEL_SERVICE,
3246                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3247                            NULL);
3248         if (ret == 0) {
3249                 tsec->sid = secid;
3250                 tsec->create_sid = 0;
3251                 tsec->keycreate_sid = 0;
3252                 tsec->sockcreate_sid = 0;
3253         }
3254         return ret;
3255 }
3256
3257 /*
3258  * set the file creation context in a security record to the same as the
3259  * objective context of the specified inode
3260  */
3261 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3262 {
3263         struct inode_security_struct *isec = inode->i_security;
3264         struct task_security_struct *tsec = new->security;
3265         u32 sid = current_sid();
3266         int ret;
3267
3268         ret = avc_has_perm(sid, isec->sid,
3269                            SECCLASS_KERNEL_SERVICE,
3270                            KERNEL_SERVICE__CREATE_FILES_AS,
3271                            NULL);
3272
3273         if (ret == 0)
3274                 tsec->create_sid = isec->sid;
3275         return ret;
3276 }
3277
3278 static int selinux_kernel_module_request(char *kmod_name)
3279 {
3280         u32 sid;
3281         struct common_audit_data ad;
3282
3283         sid = task_sid(current);
3284
3285         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3286         ad.u.kmod_name = kmod_name;
3287
3288         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3289                             SYSTEM__MODULE_REQUEST, &ad);
3290 }
3291
3292 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3293 {
3294         return current_has_perm(p, PROCESS__SETPGID);
3295 }
3296
3297 static int selinux_task_getpgid(struct task_struct *p)
3298 {
3299         return current_has_perm(p, PROCESS__GETPGID);
3300 }
3301
3302 static int selinux_task_getsid(struct task_struct *p)
3303 {
3304         return current_has_perm(p, PROCESS__GETSESSION);
3305 }
3306
3307 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3308 {
3309         *secid = task_sid(p);
3310 }
3311
3312 static int selinux_task_setnice(struct task_struct *p, int nice)
3313 {
3314         int rc;
3315
3316         rc = cap_task_setnice(p, nice);
3317         if (rc)
3318                 return rc;
3319
3320         return current_has_perm(p, PROCESS__SETSCHED);
3321 }
3322
3323 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3324 {
3325         int rc;
3326
3327         rc = cap_task_setioprio(p, ioprio);
3328         if (rc)
3329                 return rc;
3330
3331         return current_has_perm(p, PROCESS__SETSCHED);
3332 }
3333
3334 static int selinux_task_getioprio(struct task_struct *p)
3335 {
3336         return current_has_perm(p, PROCESS__GETSCHED);
3337 }
3338
3339 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3340                 struct rlimit *new_rlim)
3341 {
3342         struct rlimit *old_rlim = p->signal->rlim + resource;
3343
3344         /* Control the ability to change the hard limit (whether
3345            lowering or raising it), so that the hard limit can
3346            later be used as a safe reset point for the soft limit
3347            upon context transitions.  See selinux_bprm_committing_creds. */
3348         if (old_rlim->rlim_max != new_rlim->rlim_max)
3349                 return current_has_perm(p, PROCESS__SETRLIMIT);
3350
3351         return 0;
3352 }
3353
3354 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3355 {
3356         int rc;
3357
3358         rc = cap_task_setscheduler(p, policy, lp);
3359         if (rc)
3360                 return rc;
3361
3362         return current_has_perm(p, PROCESS__SETSCHED);
3363 }
3364
3365 static int selinux_task_getscheduler(struct task_struct *p)
3366 {
3367         return current_has_perm(p, PROCESS__GETSCHED);
3368 }
3369
3370 static int selinux_task_movememory(struct task_struct *p)
3371 {
3372         return current_has_perm(p, PROCESS__SETSCHED);
3373 }
3374
3375 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3376                                 int sig, u32 secid)
3377 {
3378         u32 perm;
3379         int rc;
3380
3381         if (!sig)
3382                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3383         else
3384                 perm = signal_to_av(sig);
3385         if (secid)
3386                 rc = avc_has_perm(secid, task_sid(p),
3387                                   SECCLASS_PROCESS, perm, NULL);
3388         else
3389                 rc = current_has_perm(p, perm);
3390         return rc;
3391 }
3392
3393 static int selinux_task_wait(struct task_struct *p)
3394 {
3395         return task_has_perm(p, current, PROCESS__SIGCHLD);
3396 }
3397
3398 static void selinux_task_to_inode(struct task_struct *p,
3399                                   struct inode *inode)
3400 {
3401         struct inode_security_struct *isec = inode->i_security;
3402         u32 sid = task_sid(p);
3403
3404         isec->sid = sid;
3405         isec->initialized = 1;
3406 }
3407
3408 /* Returns error only if unable to parse addresses */
3409 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3410                         struct common_audit_data *ad, u8 *proto)
3411 {
3412         int offset, ihlen, ret = -EINVAL;
3413         struct iphdr _iph, *ih;
3414
3415         offset = skb_network_offset(skb);
3416         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3417         if (ih == NULL)
3418                 goto out;
3419
3420         ihlen = ih->ihl * 4;
3421         if (ihlen < sizeof(_iph))
3422                 goto out;
3423
3424         ad->u.net.v4info.saddr = ih->saddr;
3425         ad->u.net.v4info.daddr = ih->daddr;
3426         ret = 0;
3427
3428         if (proto)
3429                 *proto = ih->protocol;
3430
3431         switch (ih->protocol) {
3432         case IPPROTO_TCP: {
3433                 struct tcphdr _tcph, *th;
3434
3435                 if (ntohs(ih->frag_off) & IP_OFFSET)
3436                         break;
3437
3438                 offset += ihlen;
3439                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3440                 if (th == NULL)
3441                         break;
3442
3443                 ad->u.net.sport = th->source;
3444                 ad->u.net.dport = th->dest;
3445                 break;
3446         }
3447
3448         case IPPROTO_UDP: {
3449                 struct udphdr _udph, *uh;
3450
3451                 if (ntohs(ih->frag_off) & IP_OFFSET)
3452                         break;
3453
3454                 offset += ihlen;
3455                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3456                 if (uh == NULL)
3457                         break;
3458
3459                 ad->u.net.sport = uh->source;
3460                 ad->u.net.dport = uh->dest;
3461                 break;
3462         }
3463
3464         case IPPROTO_DCCP: {
3465                 struct dccp_hdr _dccph, *dh;
3466
3467                 if (ntohs(ih->frag_off) & IP_OFFSET)
3468                         break;
3469
3470                 offset += ihlen;
3471                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3472                 if (dh == NULL)
3473                         break;
3474
3475                 ad->u.net.sport = dh->dccph_sport;
3476                 ad->u.net.dport = dh->dccph_dport;
3477                 break;
3478         }
3479
3480         default:
3481                 break;
3482         }
3483 out:
3484         return ret;
3485 }
3486
3487 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3488
3489 /* Returns error only if unable to parse addresses */
3490 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3491                         struct common_audit_data *ad, u8 *proto)
3492 {
3493         u8 nexthdr;
3494         int ret = -EINVAL, offset;
3495         struct ipv6hdr _ipv6h, *ip6;
3496
3497         offset = skb_network_offset(skb);
3498         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3499         if (ip6 == NULL)
3500                 goto out;
3501
3502         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3503         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3504         ret = 0;
3505
3506         nexthdr = ip6->nexthdr;
3507         offset += sizeof(_ipv6h);
3508         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3509         if (offset < 0)
3510                 goto out;
3511
3512         if (proto)
3513                 *proto = nexthdr;
3514
3515         switch (nexthdr) {
3516         case IPPROTO_TCP: {
3517                 struct tcphdr _tcph, *th;
3518
3519                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3520                 if (th == NULL)
3521                         break;
3522
3523                 ad->u.net.sport = th->source;
3524                 ad->u.net.dport = th->dest;
3525                 break;
3526         }
3527
3528         case IPPROTO_UDP: {
3529                 struct udphdr _udph, *uh;
3530
3531                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3532                 if (uh == NULL)
3533                         break;
3534
3535                 ad->u.net.sport = uh->source;
3536                 ad->u.net.dport = uh->dest;
3537                 break;
3538         }
3539
3540         case IPPROTO_DCCP: {
3541                 struct dccp_hdr _dccph, *dh;
3542
3543                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3544                 if (dh == NULL)
3545                         break;
3546
3547                 ad->u.net.sport = dh->dccph_sport;
3548                 ad->u.net.dport = dh->dccph_dport;
3549                 break;
3550         }
3551
3552         /* includes fragments */
3553         default:
3554                 break;
3555         }
3556 out:
3557         return ret;
3558 }
3559
3560 #endif /* IPV6 */
3561
3562 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3563                              char **_addrp, int src, u8 *proto)
3564 {
3565         char *addrp;
3566         int ret;
3567
3568         switch (ad->u.net.family) {
3569         case PF_INET:
3570                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3571                 if (ret)
3572                         goto parse_error;
3573                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3574                                        &ad->u.net.v4info.daddr);
3575                 goto okay;
3576
3577 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3578         case PF_INET6:
3579                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3580                 if (ret)
3581                         goto parse_error;
3582                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3583                                        &ad->u.net.v6info.daddr);
3584                 goto okay;
3585 #endif  /* IPV6 */
3586         default:
3587                 addrp = NULL;
3588                 goto okay;
3589         }
3590
3591 parse_error:
3592         printk(KERN_WARNING
3593                "SELinux: failure in selinux_parse_skb(),"
3594                " unable to parse packet\n");
3595         return ret;
3596
3597 okay:
3598         if (_addrp)
3599                 *_addrp = addrp;
3600         return 0;
3601 }
3602
3603 /**
3604  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3605  * @skb: the packet
3606  * @family: protocol family
3607  * @sid: the packet's peer label SID
3608  *
3609  * Description:
3610  * Check the various different forms of network peer labeling and determine
3611  * the peer label/SID for the packet; most of the magic actually occurs in
3612  * the security server function security_net_peersid_cmp().  The function
3613  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3614  * or -EACCES if @sid is invalid due to inconsistencies with the different
3615  * peer labels.
3616  *
3617  */
3618 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3619 {
3620         int err;
3621         u32 xfrm_sid;
3622         u32 nlbl_sid;
3623         u32 nlbl_type;
3624
3625         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3626         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3627
3628         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3629         if (unlikely(err)) {
3630                 printk(KERN_WARNING
3631                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3632                        " unable to determine packet's peer label\n");
3633                 return -EACCES;
3634         }
3635
3636         return 0;
3637 }
3638
3639 /* socket security operations */
3640
3641 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3642 {
3643         return tsec->sockcreate_sid ? : tsec->sid;
3644 }
3645
3646 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3647 {
3648         struct sk_security_struct *sksec = sk->sk_security;
3649         struct common_audit_data ad;
3650         u32 tsid = task_sid(task);
3651
3652         if (sksec->sid == SECINITSID_KERNEL)
3653                 return 0;
3654
3655         COMMON_AUDIT_DATA_INIT(&ad, NET);
3656         ad.u.net.sk = sk;
3657
3658         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3659 }
3660
3661 static int selinux_socket_create(int family, int type,
3662                                  int protocol, int kern)
3663 {
3664         const struct task_security_struct *tsec = current_security();
3665         u32 newsid;
3666         u16 secclass;
3667
3668         if (kern)
3669                 return 0;
3670
3671         newsid = socket_sockcreate_sid(tsec);
3672         secclass = socket_type_to_security_class(family, type, protocol);
3673         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3674 }
3675
3676 static int selinux_socket_post_create(struct socket *sock, int family,
3677                                       int type, int protocol, int kern)
3678 {
3679         const struct task_security_struct *tsec = current_security();
3680         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3681         struct sk_security_struct *sksec;
3682         int err = 0;
3683
3684         if (kern)
3685                 isec->sid = SECINITSID_KERNEL;
3686         else
3687                 isec->sid = socket_sockcreate_sid(tsec);
3688
3689         isec->sclass = socket_type_to_security_class(family, type, protocol);
3690         isec->initialized = 1;
3691
3692         if (sock->sk) {
3693                 sksec = sock->sk->sk_security;
3694                 sksec->sid = isec->sid;
3695                 sksec->sclass = isec->sclass;
3696                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3697         }
3698
3699         return err;
3700 }
3701
3702 /* Range of port numbers used to automatically bind.
3703    Need to determine whether we should perform a name_bind
3704    permission check between the socket and the port number. */
3705
3706 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3707 {
3708         struct sock *sk = sock->sk;
3709         u16 family;
3710         int err;
3711
3712         err = sock_has_perm(current, sk, SOCKET__BIND);
3713         if (err)
3714                 goto out;
3715
3716         /*
3717          * If PF_INET or PF_INET6, check name_bind permission for the port.
3718          * Multiple address binding for SCTP is not supported yet: we just
3719          * check the first address now.
3720          */
3721         family = sk->sk_family;
3722         if (family == PF_INET || family == PF_INET6) {
3723                 char *addrp;
3724                 struct sk_security_struct *sksec = sk->sk_security;
3725                 struct common_audit_data ad;
3726                 struct sockaddr_in *addr4 = NULL;
3727                 struct sockaddr_in6 *addr6 = NULL;
3728                 unsigned short snum;
3729                 u32 sid, node_perm;
3730
3731                 if (family == PF_INET) {
3732                         addr4 = (struct sockaddr_in *)address;
3733                         snum = ntohs(addr4->sin_port);
3734                         addrp = (char *)&addr4->sin_addr.s_addr;
3735                 } else {
3736                         addr6 = (struct sockaddr_in6 *)address;
3737                         snum = ntohs(addr6->sin6_port);
3738                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3739                 }
3740
3741                 if (snum) {
3742                         int low, high;
3743
3744                         inet_get_local_port_range(&low, &high);
3745
3746                         if (snum < max(PROT_SOCK, low) || snum > high) {
3747                                 err = sel_netport_sid(sk->sk_protocol,
3748                                                       snum, &sid);
3749                                 if (err)
3750                                         goto out;
3751                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3752                                 ad.u.net.sport = htons(snum);
3753                                 ad.u.net.family = family;
3754                                 err = avc_has_perm(sksec->sid, sid,
3755                                                    sksec->sclass,
3756                                                    SOCKET__NAME_BIND, &ad);
3757                                 if (err)
3758                                         goto out;
3759                         }
3760                 }
3761
3762                 switch (sksec->sclass) {
3763                 case SECCLASS_TCP_SOCKET:
3764                         node_perm = TCP_SOCKET__NODE_BIND;
3765                         break;
3766
3767                 case SECCLASS_UDP_SOCKET:
3768                         node_perm = UDP_SOCKET__NODE_BIND;
3769                         break;
3770
3771                 case SECCLASS_DCCP_SOCKET:
3772                         node_perm = DCCP_SOCKET__NODE_BIND;
3773                         break;
3774
3775                 default:
3776                         node_perm = RAWIP_SOCKET__NODE_BIND;
3777                         break;
3778                 }
3779
3780                 err = sel_netnode_sid(addrp, family, &sid);
3781                 if (err)
3782                         goto out;
3783
3784                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3785                 ad.u.net.sport = htons(snum);
3786                 ad.u.net.family = family;
3787
3788                 if (family == PF_INET)
3789                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3790                 else
3791                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3792
3793                 err = avc_has_perm(sksec->sid, sid,
3794                                    sksec->sclass, node_perm, &ad);
3795                 if (err)
3796                         goto out;
3797         }
3798 out:
3799         return err;
3800 }
3801
3802 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3803 {
3804         struct sock *sk = sock->sk;
3805         struct sk_security_struct *sksec = sk->sk_security;
3806         int err;
3807
3808         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3809         if (err)
3810                 return err;
3811
3812         /*
3813          * If a TCP or DCCP socket, check name_connect permission for the port.
3814          */
3815         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3816             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3817                 struct common_audit_data ad;
3818                 struct sockaddr_in *addr4 = NULL;
3819                 struct sockaddr_in6 *addr6 = NULL;
3820                 unsigned short snum;
3821                 u32 sid, perm;
3822
3823                 if (sk->sk_family == PF_INET) {
3824                         addr4 = (struct sockaddr_in *)address;
3825                         if (addrlen < sizeof(struct sockaddr_in))
3826                                 return -EINVAL;
3827                         snum = ntohs(addr4->sin_port);
3828                 } else {
3829                         addr6 = (struct sockaddr_in6 *)address;
3830                         if (addrlen < SIN6_LEN_RFC2133)
3831                                 return -EINVAL;
3832                         snum = ntohs(addr6->sin6_port);
3833                 }
3834
3835                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3836                 if (err)
3837                         goto out;
3838
3839                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3840                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3841
3842                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3843                 ad.u.net.dport = htons(snum);
3844                 ad.u.net.family = sk->sk_family;
3845                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3846                 if (err)
3847                         goto out;
3848         }
3849
3850         err = selinux_netlbl_socket_connect(sk, address);
3851
3852 out:
3853         return err;
3854 }
3855
3856 static int selinux_socket_listen(struct socket *sock, int backlog)
3857 {
3858         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3859 }
3860
3861 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3862 {
3863         int err;
3864         struct inode_security_struct *isec;
3865         struct inode_security_struct *newisec;
3866
3867         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3868         if (err)
3869                 return err;
3870
3871         newisec = SOCK_INODE(newsock)->i_security;
3872
3873         isec = SOCK_INODE(sock)->i_security;
3874         newisec->sclass = isec->sclass;
3875         newisec->sid = isec->sid;
3876         newisec->initialized = 1;
3877
3878         return 0;
3879 }
3880
3881 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3882                                   int size)
3883 {
3884         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3885 }
3886
3887 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3888                                   int size, int flags)
3889 {
3890         return sock_has_perm(current, sock->sk, SOCKET__READ);
3891 }
3892
3893 static int selinux_socket_getsockname(struct socket *sock)
3894 {
3895         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3896 }
3897
3898 static int selinux_socket_getpeername(struct socket *sock)
3899 {
3900         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3901 }
3902
3903 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3904 {
3905         int err;
3906
3907         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3908         if (err)
3909                 return err;
3910
3911         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3912 }
3913
3914 static int selinux_socket_getsockopt(struct socket *sock, int level,
3915                                      int optname)
3916 {
3917         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3918 }
3919
3920 static int selinux_socket_shutdown(struct socket *sock, int how)
3921 {
3922         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3923 }
3924
3925 static int selinux_socket_unix_stream_connect(struct socket *sock,
3926                                               struct socket *other,
3927                                               struct sock *newsk)
3928 {
3929         struct sk_security_struct *sksec_sock = sock->sk->sk_security;
3930         struct sk_security_struct *sksec_other = other->sk->sk_security;
3931         struct sk_security_struct *sksec_new = newsk->sk_security;
3932         struct common_audit_data ad;
3933         int err;
3934
3935         COMMON_AUDIT_DATA_INIT(&ad, NET);
3936         ad.u.net.sk = other->sk;
3937
3938         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3939                            sksec_other->sclass,
3940                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3941         if (err)
3942                 return err;
3943
3944         /* server child socket */
3945         sksec_new->peer_sid = sksec_sock->sid;
3946         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3947                                     &sksec_new->sid);
3948         if (err)
3949                 return err;
3950
3951         /* connecting socket */
3952         sksec_sock->peer_sid = sksec_new->sid;
3953
3954         return 0;
3955 }
3956
3957 static int selinux_socket_unix_may_send(struct socket *sock,
3958                                         struct socket *other)
3959 {
3960         struct sk_security_struct *ssec = sock->sk->sk_security;
3961         struct sk_security_struct *osec = other->sk->sk_security;
3962         struct common_audit_data ad;
3963
3964         COMMON_AUDIT_DATA_INIT(&ad, NET);
3965         ad.u.net.sk = other->sk;
3966
3967         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3968                             &ad);
3969 }
3970
3971 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3972                                     u32 peer_sid,
3973                                     struct common_audit_data *ad)
3974 {
3975         int err;
3976         u32 if_sid;
3977         u32 node_sid;
3978
3979         err = sel_netif_sid(ifindex, &if_sid);
3980         if (err)
3981                 return err;
3982         err = avc_has_perm(peer_sid, if_sid,
3983                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3984         if (err)
3985                 return err;
3986
3987         err = sel_netnode_sid(addrp, family, &node_sid);
3988         if (err)
3989                 return err;
3990         return avc_has_perm(peer_sid, node_sid,
3991                             SECCLASS_NODE, NODE__RECVFROM, ad);
3992 }
3993
3994 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3995                                        u16 family)
3996 {
3997         int err = 0;
3998         struct sk_security_struct *sksec = sk->sk_security;
3999         u32 peer_sid;
4000         u32 sk_sid = sksec->sid;
4001         struct common_audit_data ad;
4002         char *addrp;
4003
4004         COMMON_AUDIT_DATA_INIT(&ad, NET);
4005         ad.u.net.netif = skb->skb_iif;
4006         ad.u.net.family = family;
4007         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4008         if (err)
4009                 return err;
4010
4011         if (selinux_secmark_enabled()) {
4012                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4013                                    PACKET__RECV, &ad);
4014                 if (err)
4015                         return err;
4016         }
4017
4018         if (selinux_policycap_netpeer) {
4019                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4020                 if (err)
4021                         return err;
4022                 err = avc_has_perm(sk_sid, peer_sid,
4023                                    SECCLASS_PEER, PEER__RECV, &ad);
4024                 if (err)
4025                         selinux_netlbl_err(skb, err, 0);
4026         } else {
4027                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4028                 if (err)
4029                         return err;
4030                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4031         }
4032
4033         return err;
4034 }
4035
4036 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4037 {
4038         int err;
4039         struct sk_security_struct *sksec = sk->sk_security;
4040         u16 family = sk->sk_family;
4041         u32 sk_sid = sksec->sid;
4042         struct common_audit_data ad;
4043         char *addrp;
4044         u8 secmark_active;
4045         u8 peerlbl_active;
4046
4047         if (family != PF_INET && family != PF_INET6)
4048                 return 0;
4049
4050         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4051         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4052                 family = PF_INET;
4053
4054         /* If any sort of compatibility mode is enabled then handoff processing
4055          * to the selinux_sock_rcv_skb_compat() function to deal with the
4056          * special handling.  We do this in an attempt to keep this function
4057          * as fast and as clean as possible. */
4058         if (!selinux_policycap_netpeer)
4059                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4060
4061         secmark_active = selinux_secmark_enabled();
4062         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4063         if (!secmark_active && !peerlbl_active)
4064                 return 0;
4065
4066         COMMON_AUDIT_DATA_INIT(&ad, NET);
4067         ad.u.net.netif = skb->skb_iif;
4068         ad.u.net.family = family;
4069         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4070         if (err)
4071                 return err;
4072
4073         if (peerlbl_active) {
4074                 u32 peer_sid;
4075
4076                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4077                 if (err)
4078                         return err;
4079                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4080                                                peer_sid, &ad);
4081                 if (err) {
4082                         selinux_netlbl_err(skb, err, 0);
4083                         return err;
4084                 }
4085                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4086                                    PEER__RECV, &ad);
4087                 if (err)
4088                         selinux_netlbl_err(skb, err, 0);
4089         }
4090
4091         if (secmark_active) {
4092                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4093                                    PACKET__RECV, &ad);
4094                 if (err)
4095                         return err;
4096         }
4097
4098         return err;
4099 }
4100
4101 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4102                                             int __user *optlen, unsigned len)
4103 {
4104         int err = 0;
4105         char *scontext;
4106         u32 scontext_len;
4107         struct sk_security_struct *sksec = sock->sk->sk_security;
4108         u32 peer_sid = SECSID_NULL;
4109
4110         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4111             sksec->sclass == SECCLASS_TCP_SOCKET)
4112                 peer_sid = sksec->peer_sid;
4113         if (peer_sid == SECSID_NULL)
4114                 return -ENOPROTOOPT;
4115
4116         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4117         if (err)
4118                 return err;
4119
4120         if (scontext_len > len) {
4121                 err = -ERANGE;
4122                 goto out_len;
4123         }
4124
4125         if (copy_to_user(optval, scontext, scontext_len))
4126                 err = -EFAULT;
4127
4128 out_len:
4129         if (put_user(scontext_len, optlen))
4130                 err = -EFAULT;
4131         kfree(scontext);
4132         return err;
4133 }
4134
4135 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4136 {
4137         u32 peer_secid = SECSID_NULL;
4138         u16 family;
4139
4140         if (skb && skb->protocol == htons(ETH_P_IP))
4141                 family = PF_INET;
4142         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4143                 family = PF_INET6;
4144         else if (sock)
4145                 family = sock->sk->sk_family;
4146         else
4147                 goto out;
4148
4149         if (sock && family == PF_UNIX)
4150                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4151         else if (skb)
4152                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4153
4154 out:
4155         *secid = peer_secid;
4156         if (peer_secid == SECSID_NULL)
4157                 return -EINVAL;
4158         return 0;
4159 }
4160
4161 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4162 {
4163         struct sk_security_struct *sksec;
4164
4165         sksec = kzalloc(sizeof(*sksec), priority);
4166         if (!sksec)
4167                 return -ENOMEM;
4168
4169         sksec->peer_sid = SECINITSID_UNLABELED;
4170         sksec->sid = SECINITSID_UNLABELED;
4171         selinux_netlbl_sk_security_reset(sksec);
4172         sk->sk_security = sksec;
4173
4174         return 0;
4175 }
4176
4177 static void selinux_sk_free_security(struct sock *sk)
4178 {
4179         struct sk_security_struct *sksec = sk->sk_security;
4180
4181         sk->sk_security = NULL;
4182         selinux_netlbl_sk_security_free(sksec);
4183         kfree(sksec);
4184 }
4185
4186 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4187 {
4188         struct sk_security_struct *sksec = sk->sk_security;
4189         struct sk_security_struct *newsksec = newsk->sk_security;
4190
4191         newsksec->sid = sksec->sid;
4192         newsksec->peer_sid = sksec->peer_sid;
4193         newsksec->sclass = sksec->sclass;
4194
4195         selinux_netlbl_sk_security_reset(newsksec);
4196 }
4197
4198 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4199 {
4200         if (!sk)
4201                 *secid = SECINITSID_ANY_SOCKET;
4202         else {
4203                 struct sk_security_struct *sksec = sk->sk_security;
4204
4205                 *secid = sksec->sid;
4206         }
4207 }
4208
4209 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4210 {
4211         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4212         struct sk_security_struct *sksec = sk->sk_security;
4213
4214         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4215             sk->sk_family == PF_UNIX)
4216                 isec->sid = sksec->sid;
4217         sksec->sclass = isec->sclass;
4218 }
4219
4220 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4221                                      struct request_sock *req)
4222 {
4223         struct sk_security_struct *sksec = sk->sk_security;
4224         int err;
4225         u16 family = sk->sk_family;
4226         u32 newsid;
4227         u32 peersid;
4228
4229         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4230         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4231                 family = PF_INET;
4232
4233         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4234         if (err)
4235                 return err;
4236         if (peersid == SECSID_NULL) {
4237                 req->secid = sksec->sid;
4238                 req->peer_secid = SECSID_NULL;
4239         } else {
4240                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4241                 if (err)
4242                         return err;
4243                 req->secid = newsid;
4244                 req->peer_secid = peersid;
4245         }
4246
4247         return selinux_netlbl_inet_conn_request(req, family);
4248 }
4249
4250 static void selinux_inet_csk_clone(struct sock *newsk,
4251                                    const struct request_sock *req)
4252 {
4253         struct sk_security_struct *newsksec = newsk->sk_security;
4254
4255         newsksec->sid = req->secid;
4256         newsksec->peer_sid = req->peer_secid;
4257         /* NOTE: Ideally, we should also get the isec->sid for the
4258            new socket in sync, but we don't have the isec available yet.
4259            So we will wait until sock_graft to do it, by which
4260            time it will have been created and available. */
4261
4262         /* We don't need to take any sort of lock here as we are the only
4263          * thread with access to newsksec */
4264         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4265 }
4266
4267 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4268 {
4269         u16 family = sk->sk_family;
4270         struct sk_security_struct *sksec = sk->sk_security;
4271
4272         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4273         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4274                 family = PF_INET;
4275
4276         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4277 }
4278
4279 static void selinux_req_classify_flow(const struct request_sock *req,
4280                                       struct flowi *fl)
4281 {
4282         fl->secid = req->secid;
4283 }
4284
4285 static int selinux_tun_dev_create(void)
4286 {
4287         u32 sid = current_sid();
4288
4289         /* we aren't taking into account the "sockcreate" SID since the socket
4290          * that is being created here is not a socket in the traditional sense,
4291          * instead it is a private sock, accessible only to the kernel, and
4292          * representing a wide range of network traffic spanning multiple
4293          * connections unlike traditional sockets - check the TUN driver to
4294          * get a better understanding of why this socket is special */
4295
4296         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4297                             NULL);
4298 }
4299
4300 static void selinux_tun_dev_post_create(struct sock *sk)
4301 {
4302         struct sk_security_struct *sksec = sk->sk_security;
4303
4304         /* we don't currently perform any NetLabel based labeling here and it
4305          * isn't clear that we would want to do so anyway; while we could apply
4306          * labeling without the support of the TUN user the resulting labeled
4307          * traffic from the other end of the connection would almost certainly
4308          * cause confusion to the TUN user that had no idea network labeling
4309          * protocols were being used */
4310
4311         /* see the comments in selinux_tun_dev_create() about why we don't use
4312          * the sockcreate SID here */
4313
4314         sksec->sid = current_sid();
4315         sksec->sclass = SECCLASS_TUN_SOCKET;
4316 }
4317
4318 static int selinux_tun_dev_attach(struct sock *sk)
4319 {
4320         struct sk_security_struct *sksec = sk->sk_security;
4321         u32 sid = current_sid();
4322         int err;
4323
4324         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4325                            TUN_SOCKET__RELABELFROM, NULL);
4326         if (err)
4327                 return err;
4328         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4329                            TUN_SOCKET__RELABELTO, NULL);
4330         if (err)
4331                 return err;
4332
4333         sksec->sid = sid;
4334
4335         return 0;
4336 }
4337
4338 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4339 {
4340         int err = 0;
4341         u32 perm;
4342         struct nlmsghdr *nlh;
4343         struct sk_security_struct *sksec = sk->sk_security;
4344
4345         if (skb->len < NLMSG_SPACE(0)) {
4346                 err = -EINVAL;
4347                 goto out;
4348         }
4349         nlh = nlmsg_hdr(skb);
4350
4351         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4352         if (err) {
4353                 if (err == -EINVAL) {
4354                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4355                                   "SELinux:  unrecognized netlink message"
4356                                   " type=%hu for sclass=%hu\n",
4357                                   nlh->nlmsg_type, sksec->sclass);
4358                         if (!selinux_enforcing || security_get_allow_unknown())
4359                                 err = 0;
4360                 }
4361
4362                 /* Ignore */
4363                 if (err == -ENOENT)
4364                         err = 0;
4365                 goto out;
4366         }
4367
4368         err = sock_has_perm(current, sk, perm);
4369 out:
4370         return err;
4371 }
4372
4373 #ifdef CONFIG_NETFILTER
4374
4375 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4376                                        u16 family)
4377 {
4378         int err;
4379         char *addrp;
4380         u32 peer_sid;
4381         struct common_audit_data ad;
4382         u8 secmark_active;
4383         u8 netlbl_active;
4384         u8 peerlbl_active;
4385
4386         if (!selinux_policycap_netpeer)
4387                 return NF_ACCEPT;
4388
4389         secmark_active = selinux_secmark_enabled();
4390         netlbl_active = netlbl_enabled();
4391         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4392         if (!secmark_active && !peerlbl_active)
4393                 return NF_ACCEPT;
4394
4395         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4396                 return NF_DROP;
4397
4398         COMMON_AUDIT_DATA_INIT(&ad, NET);
4399         ad.u.net.netif = ifindex;
4400         ad.u.net.family = family;
4401         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4402                 return NF_DROP;
4403
4404         if (peerlbl_active) {
4405                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4406                                                peer_sid, &ad);
4407                 if (err) {
4408                         selinux_netlbl_err(skb, err, 1);
4409                         return NF_DROP;
4410                 }
4411         }
4412
4413         if (secmark_active)
4414                 if (avc_has_perm(peer_sid, skb->secmark,
4415                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4416                         return NF_DROP;
4417
4418         if (netlbl_active)
4419                 /* we do this in the FORWARD path and not the POST_ROUTING
4420                  * path because we want to make sure we apply the necessary
4421                  * labeling before IPsec is applied so we can leverage AH
4422                  * protection */
4423                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4424                         return NF_DROP;
4425
4426         return NF_ACCEPT;
4427 }
4428
4429 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4430                                          struct sk_buff *skb,
4431                                          const struct net_device *in,
4432                                          const struct net_device *out,
4433                                          int (*okfn)(struct sk_buff *))
4434 {
4435         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4436 }
4437
4438 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4439 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4440                                          struct sk_buff *skb,
4441                                          const struct net_device *in,
4442                                          const struct net_device *out,
4443                                          int (*okfn)(struct sk_buff *))
4444 {
4445         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4446 }
4447 #endif  /* IPV6 */
4448
4449 static unsigned int selinux_ip_output(struct sk_buff *skb,
4450                                       u16 family)
4451 {
4452         u32 sid;
4453
4454         if (!netlbl_enabled())
4455                 return NF_ACCEPT;
4456
4457         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4458          * because we want to make sure we apply the necessary labeling
4459          * before IPsec is applied so we can leverage AH protection */
4460         if (skb->sk) {
4461                 struct sk_security_struct *sksec = skb->sk->sk_security;
4462                 sid = sksec->sid;
4463         } else
4464                 sid = SECINITSID_KERNEL;
4465         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4466                 return NF_DROP;
4467
4468         return NF_ACCEPT;
4469 }
4470
4471 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4472                                         struct sk_buff *skb,
4473                                         const struct net_device *in,
4474                                         const struct net_device *out,
4475                                         int (*okfn)(struct sk_buff *))
4476 {
4477         return selinux_ip_output(skb, PF_INET);
4478 }
4479
4480 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4481                                                 int ifindex,
4482                                                 u16 family)
4483 {
4484         struct sock *sk = skb->sk;
4485         struct sk_security_struct *sksec;
4486         struct common_audit_data ad;
4487         char *addrp;
4488         u8 proto;
4489
4490         if (sk == NULL)
4491                 return NF_ACCEPT;
4492         sksec = sk->sk_security;
4493
4494         COMMON_AUDIT_DATA_INIT(&ad, NET);
4495         ad.u.net.netif = ifindex;
4496         ad.u.net.family = family;
4497         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4498                 return NF_DROP;
4499
4500         if (selinux_secmark_enabled())
4501                 if (avc_has_perm(sksec->sid, skb->secmark,
4502                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4503                         return NF_DROP;
4504
4505         if (selinux_policycap_netpeer)
4506                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4507                         return NF_DROP;
4508
4509         return NF_ACCEPT;
4510 }
4511
4512 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4513                                          u16 family)
4514 {
4515         u32 secmark_perm;
4516         u32 peer_sid;
4517         struct sock *sk;
4518         struct common_audit_data ad;
4519         char *addrp;
4520         u8 secmark_active;
4521         u8 peerlbl_active;
4522
4523         /* If any sort of compatibility mode is enabled then handoff processing
4524          * to the selinux_ip_postroute_compat() function to deal with the
4525          * special handling.  We do this in an attempt to keep this function
4526          * as fast and as clean as possible. */
4527         if (!selinux_policycap_netpeer)
4528                 return selinux_ip_postroute_compat(skb, ifindex, family);
4529 #ifdef CONFIG_XFRM
4530         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4531          * packet transformation so allow the packet to pass without any checks
4532          * since we'll have another chance to perform access control checks
4533          * when the packet is on it's final way out.
4534          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4535          *       is NULL, in this case go ahead and apply access control. */
4536         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4537                 return NF_ACCEPT;
4538 #endif
4539         secmark_active = selinux_secmark_enabled();
4540         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4541         if (!secmark_active && !peerlbl_active)
4542                 return NF_ACCEPT;
4543
4544         /* if the packet is being forwarded then get the peer label from the
4545          * packet itself; otherwise check to see if it is from a local
4546          * application or the kernel, if from an application get the peer label
4547          * from the sending socket, otherwise use the kernel's sid */
4548         sk = skb->sk;
4549         if (sk == NULL) {
4550                 switch (family) {
4551                 case PF_INET:
4552                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4553                                 secmark_perm = PACKET__FORWARD_OUT;
4554                         else
4555                                 secmark_perm = PACKET__SEND;
4556                         break;
4557                 case PF_INET6:
4558                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4559                                 secmark_perm = PACKET__FORWARD_OUT;
4560                         else
4561                                 secmark_perm = PACKET__SEND;
4562                         break;
4563                 default:
4564                         return NF_DROP;
4565                 }
4566                 if (secmark_perm == PACKET__FORWARD_OUT) {
4567                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4568                                 return NF_DROP;
4569                 } else
4570                         peer_sid = SECINITSID_KERNEL;
4571         } else {
4572                 struct sk_security_struct *sksec = sk->sk_security;
4573                 peer_sid = sksec->sid;
4574                 secmark_perm = PACKET__SEND;
4575         }
4576
4577         COMMON_AUDIT_DATA_INIT(&ad, NET);
4578         ad.u.net.netif = ifindex;
4579         ad.u.net.family = family;
4580         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4581                 return NF_DROP;
4582
4583         if (secmark_active)
4584                 if (avc_has_perm(peer_sid, skb->secmark,
4585                                  SECCLASS_PACKET, secmark_perm, &ad))
4586                         return NF_DROP;
4587
4588         if (peerlbl_active) {
4589                 u32 if_sid;
4590                 u32 node_sid;
4591
4592                 if (sel_netif_sid(ifindex, &if_sid))
4593                         return NF_DROP;
4594                 if (avc_has_perm(peer_sid, if_sid,
4595                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4596                         return NF_DROP;
4597
4598                 if (sel_netnode_sid(addrp, family, &node_sid))
4599                         return NF_DROP;
4600                 if (avc_has_perm(peer_sid, node_sid,
4601                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4602                         return NF_DROP;
4603         }
4604
4605         return NF_ACCEPT;
4606 }
4607
4608 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4609                                            struct sk_buff *skb,
4610                                            const struct net_device *in,
4611                                            const struct net_device *out,
4612                                            int (*okfn)(struct sk_buff *))
4613 {
4614         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4615 }
4616
4617 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4618 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4619                                            struct sk_buff *skb,
4620                                            const struct net_device *in,
4621                                            const struct net_device *out,
4622                                            int (*okfn)(struct sk_buff *))
4623 {
4624         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4625 }
4626 #endif  /* IPV6 */
4627
4628 #endif  /* CONFIG_NETFILTER */
4629
4630 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4631 {
4632         int err;
4633
4634         err = cap_netlink_send(sk, skb);
4635         if (err)
4636                 return err;
4637
4638         return selinux_nlmsg_perm(sk, skb);
4639 }
4640
4641 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4642 {
4643         int err;
4644         struct common_audit_data ad;
4645
4646         err = cap_netlink_recv(skb, capability);
4647         if (err)
4648                 return err;
4649
4650         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4651         ad.u.cap = capability;
4652
4653         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4654                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4655 }
4656
4657 static int ipc_alloc_security(struct task_struct *task,
4658                               struct kern_ipc_perm *perm,
4659                               u16 sclass)
4660 {
4661         struct ipc_security_struct *isec;
4662         u32 sid;
4663
4664         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4665         if (!isec)
4666                 return -ENOMEM;
4667
4668         sid = task_sid(task);
4669         isec->sclass = sclass;
4670         isec->sid = sid;
4671         perm->security = isec;
4672
4673         return 0;
4674 }
4675
4676 static void ipc_free_security(struct kern_ipc_perm *perm)
4677 {
4678         struct ipc_security_struct *isec = perm->security;
4679         perm->security = NULL;
4680         kfree(isec);
4681 }
4682
4683 static int msg_msg_alloc_security(struct msg_msg *msg)
4684 {
4685         struct msg_security_struct *msec;
4686
4687         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4688         if (!msec)
4689                 return -ENOMEM;
4690
4691         msec->sid = SECINITSID_UNLABELED;
4692         msg->security = msec;
4693
4694         return 0;
4695 }
4696
4697 static void msg_msg_free_security(struct msg_msg *msg)
4698 {
4699         struct msg_security_struct *msec = msg->security;
4700
4701         msg->security = NULL;
4702         kfree(msec);
4703 }
4704
4705 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4706                         u32 perms)
4707 {
4708         struct ipc_security_struct *isec;
4709         struct common_audit_data ad;
4710         u32 sid = current_sid();
4711
4712         isec = ipc_perms->security;
4713
4714         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4715         ad.u.ipc_id = ipc_perms->key;
4716
4717         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4718 }
4719
4720 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4721 {
4722         return msg_msg_alloc_security(msg);
4723 }
4724
4725 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4726 {
4727         msg_msg_free_security(msg);
4728 }
4729
4730 /* message queue security operations */
4731 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4732 {
4733         struct ipc_security_struct *isec;
4734         struct common_audit_data ad;
4735         u32 sid = current_sid();
4736         int rc;
4737
4738         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4739         if (rc)
4740                 return rc;
4741
4742         isec = msq->q_perm.security;
4743
4744         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4745         ad.u.ipc_id = msq->q_perm.key;
4746
4747         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4748                           MSGQ__CREATE, &ad);
4749         if (rc) {
4750                 ipc_free_security(&msq->q_perm);
4751                 return rc;
4752         }
4753         return 0;
4754 }
4755
4756 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4757 {
4758         ipc_free_security(&msq->q_perm);
4759 }
4760
4761 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4762 {
4763         struct ipc_security_struct *isec;
4764         struct common_audit_data ad;
4765         u32 sid = current_sid();
4766
4767         isec = msq->q_perm.security;
4768
4769         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4770         ad.u.ipc_id = msq->q_perm.key;
4771
4772         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4773                             MSGQ__ASSOCIATE, &ad);
4774 }
4775
4776 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4777 {
4778         int err;
4779         int perms;
4780
4781         switch (cmd) {
4782         case IPC_INFO:
4783         case MSG_INFO:
4784                 /* No specific object, just general system-wide information. */
4785                 return task_has_system(current, SYSTEM__IPC_INFO);
4786         case IPC_STAT:
4787         case MSG_STAT:
4788                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4789                 break;
4790         case IPC_SET:
4791                 perms = MSGQ__SETATTR;
4792                 break;
4793         case IPC_RMID:
4794                 perms = MSGQ__DESTROY;
4795                 break;
4796         default:
4797                 return 0;
4798         }
4799
4800         err = ipc_has_perm(&msq->q_perm, perms);
4801         return err;
4802 }
4803
4804 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4805 {
4806         struct ipc_security_struct *isec;
4807         struct msg_security_struct *msec;
4808         struct common_audit_data ad;
4809         u32 sid = current_sid();
4810         int rc;
4811
4812         isec = msq->q_perm.security;
4813         msec = msg->security;
4814
4815         /*
4816          * First time through, need to assign label to the message
4817          */
4818         if (msec->sid == SECINITSID_UNLABELED) {
4819                 /*
4820                  * Compute new sid based on current process and
4821                  * message queue this message will be stored in
4822                  */
4823                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4824                                              &msec->sid);
4825                 if (rc)
4826                         return rc;
4827         }
4828
4829         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4830         ad.u.ipc_id = msq->q_perm.key;
4831
4832         /* Can this process write to the queue? */
4833         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4834                           MSGQ__WRITE, &ad);
4835         if (!rc)
4836                 /* Can this process send the message */
4837                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4838                                   MSG__SEND, &ad);
4839         if (!rc)
4840                 /* Can the message be put in the queue? */
4841                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4842                                   MSGQ__ENQUEUE, &ad);
4843
4844         return rc;
4845 }
4846
4847 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4848                                     struct task_struct *target,
4849                                     long type, int mode)
4850 {
4851         struct ipc_security_struct *isec;
4852         struct msg_security_struct *msec;
4853         struct common_audit_data ad;
4854         u32 sid = task_sid(target);
4855         int rc;
4856
4857         isec = msq->q_perm.security;
4858         msec = msg->security;
4859
4860         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4861         ad.u.ipc_id = msq->q_perm.key;
4862
4863         rc = avc_has_perm(sid, isec->sid,
4864                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4865         if (!rc)
4866                 rc = avc_has_perm(sid, msec->sid,
4867                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4868         return rc;
4869 }
4870
4871 /* Shared Memory security operations */
4872 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4873 {
4874         struct ipc_security_struct *isec;
4875         struct common_audit_data ad;
4876         u32 sid = current_sid();
4877         int rc;
4878
4879         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4880         if (rc)
4881                 return rc;
4882
4883         isec = shp->shm_perm.security;
4884
4885         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4886         ad.u.ipc_id = shp->shm_perm.key;
4887
4888         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4889                           SHM__CREATE, &ad);
4890         if (rc) {
4891                 ipc_free_security(&shp->shm_perm);
4892                 return rc;
4893         }
4894         return 0;
4895 }
4896
4897 static void selinux_shm_free_security(struct shmid_kernel *shp)
4898 {
4899         ipc_free_security(&shp->shm_perm);
4900 }
4901
4902 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4903 {
4904         struct ipc_security_struct *isec;
4905         struct common_audit_data ad;
4906         u32 sid = current_sid();
4907
4908         isec = shp->shm_perm.security;
4909
4910         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4911         ad.u.ipc_id = shp->shm_perm.key;
4912
4913         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4914                             SHM__ASSOCIATE, &ad);
4915 }
4916
4917 /* Note, at this point, shp is locked down */
4918 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4919 {
4920         int perms;
4921         int err;
4922
4923         switch (cmd) {
4924         case IPC_INFO:
4925         case SHM_INFO:
4926                 /* No specific object, just general system-wide information. */
4927                 return task_has_system(current, SYSTEM__IPC_INFO);
4928         case IPC_STAT:
4929         case SHM_STAT:
4930                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4931                 break;
4932         case IPC_SET:
4933                 perms = SHM__SETATTR;
4934                 break;
4935         case SHM_LOCK:
4936         case SHM_UNLOCK:
4937                 perms = SHM__LOCK;
4938                 break;
4939         case IPC_RMID:
4940                 perms = SHM__DESTROY;
4941                 break;
4942         default:
4943                 return 0;
4944         }
4945
4946         err = ipc_has_perm(&shp->shm_perm, perms);
4947         return err;
4948 }
4949
4950 static int selinux_shm_shmat(struct shmid_kernel *shp,
4951                              char __user *shmaddr, int shmflg)
4952 {
4953         u32 perms;
4954
4955         if (shmflg & SHM_RDONLY)
4956                 perms = SHM__READ;
4957         else
4958                 perms = SHM__READ | SHM__WRITE;
4959
4960         return ipc_has_perm(&shp->shm_perm, perms);
4961 }
4962
4963 /* Semaphore security operations */
4964 static int selinux_sem_alloc_security(struct sem_array *sma)
4965 {
4966         struct ipc_security_struct *isec;
4967         struct common_audit_data ad;
4968         u32 sid = current_sid();
4969         int rc;
4970
4971         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4972         if (rc)
4973                 return rc;
4974
4975         isec = sma->sem_perm.security;
4976
4977         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4978         ad.u.ipc_id = sma->sem_perm.key;
4979
4980         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4981                           SEM__CREATE, &ad);
4982         if (rc) {
4983                 ipc_free_security(&sma->sem_perm);
4984                 return rc;
4985         }
4986         return 0;
4987 }
4988
4989 static void selinux_sem_free_security(struct sem_array *sma)
4990 {
4991         ipc_free_security(&sma->sem_perm);
4992 }
4993
4994 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4995 {
4996         struct ipc_security_struct *isec;
4997         struct common_audit_data ad;
4998         u32 sid = current_sid();
4999
5000         isec = sma->sem_perm.security;
5001
5002         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5003         ad.u.ipc_id = sma->sem_perm.key;
5004
5005         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5006                             SEM__ASSOCIATE, &ad);
5007 }
5008
5009 /* Note, at this point, sma is locked down */
5010 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5011 {
5012         int err;
5013         u32 perms;
5014
5015         switch (cmd) {
5016         case IPC_INFO:
5017         case SEM_INFO:
5018                 /* No specific object, just general system-wide information. */
5019                 return task_has_system(current, SYSTEM__IPC_INFO);
5020         case GETPID:
5021         case GETNCNT:
5022         case GETZCNT:
5023                 perms = SEM__GETATTR;
5024                 break;
5025         case GETVAL:
5026         case GETALL:
5027                 perms = SEM__READ;
5028                 break;
5029         case SETVAL:
5030         case SETALL:
5031                 perms = SEM__WRITE;
5032                 break;
5033         case IPC_RMID:
5034                 perms = SEM__DESTROY;
5035                 break;
5036         case IPC_SET:
5037                 perms = SEM__SETATTR;
5038                 break;
5039         case IPC_STAT:
5040         case SEM_STAT:
5041                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5042                 break;
5043         default:
5044                 return 0;
5045         }
5046
5047         err = ipc_has_perm(&sma->sem_perm, perms);
5048         return err;
5049 }
5050
5051 static int selinux_sem_semop(struct sem_array *sma,
5052                              struct sembuf *sops, unsigned nsops, int alter)
5053 {
5054         u32 perms;
5055
5056         if (alter)
5057                 perms = SEM__READ | SEM__WRITE;
5058         else
5059                 perms = SEM__READ;
5060
5061         return ipc_has_perm(&sma->sem_perm, perms);
5062 }
5063
5064 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5065 {
5066         u32 av = 0;
5067
5068         av = 0;
5069         if (flag & S_IRUGO)
5070                 av |= IPC__UNIX_READ;
5071         if (flag & S_IWUGO)
5072                 av |= IPC__UNIX_WRITE;
5073
5074         if (av == 0)
5075                 return 0;
5076
5077         return ipc_has_perm(ipcp, av);
5078 }
5079
5080 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5081 {
5082         struct ipc_security_struct *isec = ipcp->security;
5083         *secid = isec->sid;
5084 }
5085
5086 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5087 {
5088         if (inode)
5089                 inode_doinit_with_dentry(inode, dentry);
5090 }
5091
5092 static int selinux_getprocattr(struct task_struct *p,
5093                                char *name, char **value)
5094 {
5095         const struct task_security_struct *__tsec;
5096         u32 sid;
5097         int error;
5098         unsigned len;
5099
5100         if (current != p) {
5101                 error = current_has_perm(p, PROCESS__GETATTR);
5102                 if (error)
5103                         return error;
5104         }
5105
5106         rcu_read_lock();
5107         __tsec = __task_cred(p)->security;
5108
5109         if (!strcmp(name, "current"))
5110                 sid = __tsec->sid;
5111         else if (!strcmp(name, "prev"))
5112                 sid = __tsec->osid;
5113         else if (!strcmp(name, "exec"))
5114                 sid = __tsec->exec_sid;
5115         else if (!strcmp(name, "fscreate"))
5116                 sid = __tsec->create_sid;
5117         else if (!strcmp(name, "keycreate"))
5118                 sid = __tsec->keycreate_sid;
5119         else if (!strcmp(name, "sockcreate"))
5120                 sid = __tsec->sockcreate_sid;
5121         else
5122                 goto invalid;
5123         rcu_read_unlock();
5124
5125         if (!sid)
5126                 return 0;
5127
5128         error = security_sid_to_context(sid, value, &len);
5129         if (error)
5130                 return error;
5131         return len;
5132
5133 invalid:
5134         rcu_read_unlock();
5135         return -EINVAL;
5136 }
5137
5138 static int selinux_setprocattr(struct task_struct *p,
5139                                char *name, void *value, size_t size)
5140 {
5141         struct task_security_struct *tsec;
5142         struct task_struct *tracer;
5143         struct cred *new;
5144         u32 sid = 0, ptsid;
5145         int error;
5146         char *str = value;
5147
5148         if (current != p) {
5149                 /* SELinux only allows a process to change its own
5150                    security attributes. */
5151                 return -EACCES;
5152         }
5153
5154         /*
5155          * Basic control over ability to set these attributes at all.
5156          * current == p, but we'll pass them separately in case the
5157          * above restriction is ever removed.
5158          */
5159         if (!strcmp(name, "exec"))
5160                 error = current_has_perm(p, PROCESS__SETEXEC);
5161         else if (!strcmp(name, "fscreate"))
5162                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5163         else if (!strcmp(name, "keycreate"))
5164                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5165         else if (!strcmp(name, "sockcreate"))
5166                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5167         else if (!strcmp(name, "current"))
5168                 error = current_has_perm(p, PROCESS__SETCURRENT);
5169         else
5170                 error = -EINVAL;
5171         if (error)
5172                 return error;
5173
5174         /* Obtain a SID for the context, if one was specified. */
5175         if (size && str[1] && str[1] != '\n') {
5176                 if (str[size-1] == '\n') {
5177                         str[size-1] = 0;
5178                         size--;
5179                 }
5180                 error = security_context_to_sid(value, size, &sid);
5181                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5182                         if (!capable(CAP_MAC_ADMIN))
5183                                 return error;
5184                         error = security_context_to_sid_force(value, size,
5185                                                               &sid);
5186                 }
5187                 if (error)
5188                         return error;
5189         }
5190
5191         new = prepare_creds();
5192         if (!new)
5193                 return -ENOMEM;
5194
5195         /* Permission checking based on the specified context is
5196            performed during the actual operation (execve,
5197            open/mkdir/...), when we know the full context of the
5198            operation.  See selinux_bprm_set_creds for the execve
5199            checks and may_create for the file creation checks. The
5200            operation will then fail if the context is not permitted. */
5201         tsec = new->security;
5202         if (!strcmp(name, "exec")) {
5203                 tsec->exec_sid = sid;
5204         } else if (!strcmp(name, "fscreate")) {
5205                 tsec->create_sid = sid;
5206         } else if (!strcmp(name, "keycreate")) {
5207                 error = may_create_key(sid, p);
5208                 if (error)
5209                         goto abort_change;
5210                 tsec->keycreate_sid = sid;
5211         } else if (!strcmp(name, "sockcreate")) {
5212                 tsec->sockcreate_sid = sid;
5213         } else if (!strcmp(name, "current")) {
5214                 error = -EINVAL;
5215                 if (sid == 0)
5216                         goto abort_change;
5217
5218                 /* Only allow single threaded processes to change context */
5219                 error = -EPERM;
5220                 if (!current_is_single_threaded()) {
5221                         error = security_bounded_transition(tsec->sid, sid);
5222                         if (error)
5223                                 goto abort_change;
5224                 }
5225
5226                 /* Check permissions for the transition. */
5227                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5228                                      PROCESS__DYNTRANSITION, NULL);
5229                 if (error)
5230                         goto abort_change;
5231
5232                 /* Check for ptracing, and update the task SID if ok.
5233                    Otherwise, leave SID unchanged and fail. */
5234                 ptsid = 0;
5235                 task_lock(p);
5236                 tracer = tracehook_tracer_task(p);
5237                 if (tracer)
5238                         ptsid = task_sid(tracer);
5239                 task_unlock(p);
5240
5241                 if (tracer) {
5242                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5243                                              PROCESS__PTRACE, NULL);
5244                         if (error)
5245                                 goto abort_change;
5246                 }
5247
5248                 tsec->sid = sid;
5249         } else {
5250                 error = -EINVAL;
5251                 goto abort_change;
5252         }
5253
5254         commit_creds(new);
5255         return size;
5256
5257 abort_change:
5258         abort_creds(new);
5259         return error;
5260 }
5261
5262 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5263 {
5264         return security_sid_to_context(secid, secdata, seclen);
5265 }
5266
5267 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5268 {
5269         return security_context_to_sid(secdata, seclen, secid);
5270 }
5271
5272 static void selinux_release_secctx(char *secdata, u32 seclen)
5273 {
5274         kfree(secdata);
5275 }
5276
5277 /*
5278  *      called with inode->i_mutex locked
5279  */
5280 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5281 {
5282         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5283 }
5284
5285 /*
5286  *      called with inode->i_mutex locked
5287  */
5288 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5289 {
5290         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5291 }
5292
5293 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5294 {
5295         int len = 0;
5296         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5297                                                 ctx, true);
5298         if (len < 0)
5299                 return len;
5300         *ctxlen = len;
5301         return 0;
5302 }
5303 #ifdef CONFIG_KEYS
5304
5305 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5306                              unsigned long flags)
5307 {
5308         const struct task_security_struct *tsec;
5309         struct key_security_struct *ksec;
5310
5311         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5312         if (!ksec)
5313                 return -ENOMEM;
5314
5315         tsec = cred->security;
5316         if (tsec->keycreate_sid)
5317                 ksec->sid = tsec->keycreate_sid;
5318         else
5319                 ksec->sid = tsec->sid;
5320
5321         k->security = ksec;
5322         return 0;
5323 }
5324
5325 static void selinux_key_free(struct key *k)
5326 {
5327         struct key_security_struct *ksec = k->security;
5328
5329         k->security = NULL;
5330         kfree(ksec);
5331 }
5332
5333 static int selinux_key_permission(key_ref_t key_ref,
5334                                   const struct cred *cred,
5335                                   key_perm_t perm)
5336 {
5337         struct key *key;
5338         struct key_security_struct *ksec;
5339         u32 sid;
5340
5341         /* if no specific permissions are requested, we skip the
5342            permission check. No serious, additional covert channels
5343            appear to be created. */
5344         if (perm == 0)
5345                 return 0;
5346
5347         sid = cred_sid(cred);
5348
5349         key = key_ref_to_ptr(key_ref);
5350         ksec = key->security;
5351
5352         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5353 }
5354
5355 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5356 {
5357         struct key_security_struct *ksec = key->security;
5358         char *context = NULL;
5359         unsigned len;
5360         int rc;
5361
5362         rc = security_sid_to_context(ksec->sid, &context, &len);
5363         if (!rc)
5364                 rc = len;
5365         *_buffer = context;
5366         return rc;
5367 }
5368
5369 #endif
5370
5371 static struct security_operations selinux_ops = {
5372         .name =                         "selinux",
5373
5374         .ptrace_access_check =          selinux_ptrace_access_check,
5375         .ptrace_traceme =               selinux_ptrace_traceme,
5376         .capget =                       selinux_capget,
5377         .capset =                       selinux_capset,
5378         .sysctl =                       selinux_sysctl,
5379         .capable =                      selinux_capable,
5380         .quotactl =                     selinux_quotactl,
5381         .quota_on =                     selinux_quota_on,
5382         .syslog =                       selinux_syslog,
5383         .vm_enough_memory =             selinux_vm_enough_memory,
5384
5385         .netlink_send =                 selinux_netlink_send,
5386         .netlink_recv =                 selinux_netlink_recv,
5387
5388         .bprm_set_creds =               selinux_bprm_set_creds,
5389         .bprm_committing_creds =        selinux_bprm_committing_creds,
5390         .bprm_committed_creds =         selinux_bprm_committed_creds,
5391         .bprm_secureexec =              selinux_bprm_secureexec,
5392
5393         .sb_alloc_security =            selinux_sb_alloc_security,
5394         .sb_free_security =             selinux_sb_free_security,
5395         .sb_copy_data =                 selinux_sb_copy_data,
5396         .sb_kern_mount =                selinux_sb_kern_mount,
5397         .sb_show_options =              selinux_sb_show_options,
5398         .sb_statfs =                    selinux_sb_statfs,
5399         .sb_mount =                     selinux_mount,
5400         .sb_umount =                    selinux_umount,
5401         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5402         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5403         .sb_parse_opts_str =            selinux_parse_opts_str,
5404
5405
5406         .inode_alloc_security =         selinux_inode_alloc_security,
5407         .inode_free_security =          selinux_inode_free_security,
5408         .inode_init_security =          selinux_inode_init_security,
5409         .inode_create =                 selinux_inode_create,
5410         .inode_link =                   selinux_inode_link,
5411         .inode_unlink =                 selinux_inode_unlink,
5412         .inode_symlink =                selinux_inode_symlink,
5413         .inode_mkdir =                  selinux_inode_mkdir,
5414         .inode_rmdir =                  selinux_inode_rmdir,
5415         .inode_mknod =                  selinux_inode_mknod,
5416         .inode_rename =                 selinux_inode_rename,
5417         .inode_readlink =               selinux_inode_readlink,
5418         .inode_follow_link =            selinux_inode_follow_link,
5419         .inode_permission =             selinux_inode_permission,
5420         .inode_setattr =                selinux_inode_setattr,
5421         .inode_getattr =                selinux_inode_getattr,
5422         .inode_setxattr =               selinux_inode_setxattr,
5423         .inode_post_setxattr =          selinux_inode_post_setxattr,
5424         .inode_getxattr =               selinux_inode_getxattr,
5425         .inode_listxattr =              selinux_inode_listxattr,
5426         .inode_removexattr =            selinux_inode_removexattr,
5427         .inode_getsecurity =            selinux_inode_getsecurity,
5428         .inode_setsecurity =            selinux_inode_setsecurity,
5429         .inode_listsecurity =           selinux_inode_listsecurity,
5430         .inode_getsecid =               selinux_inode_getsecid,
5431
5432         .file_permission =              selinux_file_permission,
5433         .file_alloc_security =          selinux_file_alloc_security,
5434         .file_free_security =           selinux_file_free_security,
5435         .file_ioctl =                   selinux_file_ioctl,
5436         .file_mmap =                    selinux_file_mmap,
5437         .file_mprotect =                selinux_file_mprotect,
5438         .file_lock =                    selinux_file_lock,
5439         .file_fcntl =                   selinux_file_fcntl,
5440         .file_set_fowner =              selinux_file_set_fowner,
5441         .file_send_sigiotask =          selinux_file_send_sigiotask,
5442         .file_receive =                 selinux_file_receive,
5443
5444         .dentry_open =                  selinux_dentry_open,
5445
5446         .task_create =                  selinux_task_create,
5447         .cred_alloc_blank =             selinux_cred_alloc_blank,
5448         .cred_free =                    selinux_cred_free,
5449         .cred_prepare =                 selinux_cred_prepare,
5450         .cred_transfer =                selinux_cred_transfer,
5451         .kernel_act_as =                selinux_kernel_act_as,
5452         .kernel_create_files_as =       selinux_kernel_create_files_as,
5453         .kernel_module_request =        selinux_kernel_module_request,
5454         .task_setpgid =                 selinux_task_setpgid,
5455         .task_getpgid =                 selinux_task_getpgid,
5456         .task_getsid =                  selinux_task_getsid,
5457         .task_getsecid =                selinux_task_getsecid,
5458         .task_setnice =                 selinux_task_setnice,
5459         .task_setioprio =               selinux_task_setioprio,
5460         .task_getioprio =               selinux_task_getioprio,
5461         .task_setrlimit =               selinux_task_setrlimit,
5462         .task_setscheduler =            selinux_task_setscheduler,
5463         .task_getscheduler =            selinux_task_getscheduler,
5464         .task_movememory =              selinux_task_movememory,
5465         .task_kill =                    selinux_task_kill,
5466         .task_wait =                    selinux_task_wait,
5467         .task_to_inode =                selinux_task_to_inode,
5468
5469         .ipc_permission =               selinux_ipc_permission,
5470         .ipc_getsecid =                 selinux_ipc_getsecid,
5471
5472         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5473         .msg_msg_free_security =        selinux_msg_msg_free_security,
5474
5475         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5476         .msg_queue_free_security =      selinux_msg_queue_free_security,
5477         .msg_queue_associate =          selinux_msg_queue_associate,
5478         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5479         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5480         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5481
5482         .shm_alloc_security =           selinux_shm_alloc_security,
5483         .shm_free_security =            selinux_shm_free_security,
5484         .shm_associate =                selinux_shm_associate,
5485         .shm_shmctl =                   selinux_shm_shmctl,
5486         .shm_shmat =                    selinux_shm_shmat,
5487
5488         .sem_alloc_security =           selinux_sem_alloc_security,
5489         .sem_free_security =            selinux_sem_free_security,
5490         .sem_associate =                selinux_sem_associate,
5491         .sem_semctl =                   selinux_sem_semctl,
5492         .sem_semop =                    selinux_sem_semop,
5493
5494         .d_instantiate =                selinux_d_instantiate,
5495
5496         .getprocattr =                  selinux_getprocattr,
5497         .setprocattr =                  selinux_setprocattr,
5498
5499         .secid_to_secctx =              selinux_secid_to_secctx,
5500         .secctx_to_secid =              selinux_secctx_to_secid,
5501         .release_secctx =               selinux_release_secctx,
5502         .inode_notifysecctx =           selinux_inode_notifysecctx,
5503         .inode_setsecctx =              selinux_inode_setsecctx,
5504         .inode_getsecctx =              selinux_inode_getsecctx,
5505
5506         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5507         .unix_may_send =                selinux_socket_unix_may_send,
5508
5509         .socket_create =                selinux_socket_create,
5510         .socket_post_create =           selinux_socket_post_create,
5511         .socket_bind =                  selinux_socket_bind,
5512         .socket_connect =               selinux_socket_connect,
5513         .socket_listen =                selinux_socket_listen,
5514         .socket_accept =                selinux_socket_accept,
5515         .socket_sendmsg =               selinux_socket_sendmsg,
5516         .socket_recvmsg =               selinux_socket_recvmsg,
5517         .socket_getsockname =           selinux_socket_getsockname,
5518         .socket_getpeername =           selinux_socket_getpeername,
5519         .socket_getsockopt =            selinux_socket_getsockopt,
5520         .socket_setsockopt =            selinux_socket_setsockopt,
5521         .socket_shutdown =              selinux_socket_shutdown,
5522         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5523         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5524         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5525         .sk_alloc_security =            selinux_sk_alloc_security,
5526         .sk_free_security =             selinux_sk_free_security,
5527         .sk_clone_security =            selinux_sk_clone_security,
5528         .sk_getsecid =                  selinux_sk_getsecid,
5529         .sock_graft =                   selinux_sock_graft,
5530         .inet_conn_request =            selinux_inet_conn_request,
5531         .inet_csk_clone =               selinux_inet_csk_clone,
5532         .inet_conn_established =        selinux_inet_conn_established,
5533         .req_classify_flow =            selinux_req_classify_flow,
5534         .tun_dev_create =               selinux_tun_dev_create,
5535         .tun_dev_post_create =          selinux_tun_dev_post_create,
5536         .tun_dev_attach =               selinux_tun_dev_attach,
5537
5538 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5539         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5540         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5541         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5542         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5543         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5544         .xfrm_state_free_security =     selinux_xfrm_state_free,
5545         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5546         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5547         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5548         .xfrm_decode_session =          selinux_xfrm_decode_session,
5549 #endif
5550
5551 #ifdef CONFIG_KEYS
5552         .key_alloc =                    selinux_key_alloc,
5553         .key_free =                     selinux_key_free,
5554         .key_permission =               selinux_key_permission,
5555         .key_getsecurity =              selinux_key_getsecurity,
5556 #endif
5557
5558 #ifdef CONFIG_AUDIT
5559         .audit_rule_init =              selinux_audit_rule_init,
5560         .audit_rule_known =             selinux_audit_rule_known,
5561         .audit_rule_match =             selinux_audit_rule_match,
5562         .audit_rule_free =              selinux_audit_rule_free,
5563 #endif
5564 };
5565
5566 static __init int selinux_init(void)
5567 {
5568         if (!security_module_enable(&selinux_ops)) {
5569                 selinux_enabled = 0;
5570                 return 0;
5571         }
5572
5573         if (!selinux_enabled) {
5574                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5575                 return 0;
5576         }
5577
5578         printk(KERN_INFO "SELinux:  Initializing.\n");
5579
5580         /* Set the security state for the initial task. */
5581         cred_init_security();
5582
5583         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5584
5585         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5586                                             sizeof(struct inode_security_struct),
5587                                             0, SLAB_PANIC, NULL);
5588         avc_init();
5589
5590         if (register_security(&selinux_ops))
5591                 panic("SELinux: Unable to register with kernel.\n");
5592
5593         if (selinux_enforcing)
5594                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5595         else
5596                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5597
5598         return 0;
5599 }
5600
5601 static void delayed_superblock_init(struct super_block *sb, void *unused)
5602 {
5603         superblock_doinit(sb, NULL);
5604 }
5605
5606 void selinux_complete_init(void)
5607 {
5608         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5609
5610         /* Set up any superblocks initialized prior to the policy load. */
5611         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5612         iterate_supers(delayed_superblock_init, NULL);
5613 }
5614
5615 /* SELinux requires early initialization in order to label
5616    all processes and objects when they are created. */
5617 security_initcall(selinux_init);
5618
5619 #if defined(CONFIG_NETFILTER)
5620
5621 static struct nf_hook_ops selinux_ipv4_ops[] = {
5622         {
5623                 .hook =         selinux_ipv4_postroute,
5624                 .owner =        THIS_MODULE,
5625                 .pf =           PF_INET,
5626                 .hooknum =      NF_INET_POST_ROUTING,
5627                 .priority =     NF_IP_PRI_SELINUX_LAST,
5628         },
5629         {
5630                 .hook =         selinux_ipv4_forward,
5631                 .owner =        THIS_MODULE,
5632                 .pf =           PF_INET,
5633                 .hooknum =      NF_INET_FORWARD,
5634                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5635         },
5636         {
5637                 .hook =         selinux_ipv4_output,
5638                 .owner =        THIS_MODULE,
5639                 .pf =           PF_INET,
5640                 .hooknum =      NF_INET_LOCAL_OUT,
5641                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5642         }
5643 };
5644
5645 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5646
5647 static struct nf_hook_ops selinux_ipv6_ops[] = {
5648         {
5649                 .hook =         selinux_ipv6_postroute,
5650                 .owner =        THIS_MODULE,
5651                 .pf =           PF_INET6,
5652                 .hooknum =      NF_INET_POST_ROUTING,
5653                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5654         },
5655         {
5656                 .hook =         selinux_ipv6_forward,
5657                 .owner =        THIS_MODULE,
5658                 .pf =           PF_INET6,
5659                 .hooknum =      NF_INET_FORWARD,
5660                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5661         }
5662 };
5663
5664 #endif  /* IPV6 */
5665
5666 static int __init selinux_nf_ip_init(void)
5667 {
5668         int err = 0;
5669
5670         if (!selinux_enabled)
5671                 goto out;
5672
5673         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5674
5675         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5676         if (err)
5677                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5678
5679 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5680         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5681         if (err)
5682                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5683 #endif  /* IPV6 */
5684
5685 out:
5686         return err;
5687 }
5688
5689 __initcall(selinux_nf_ip_init);
5690
5691 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5692 static void selinux_nf_ip_exit(void)
5693 {
5694         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5695
5696         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5697 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5698         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5699 #endif  /* IPV6 */
5700 }
5701 #endif
5702
5703 #else /* CONFIG_NETFILTER */
5704
5705 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5706 #define selinux_nf_ip_exit()
5707 #endif
5708
5709 #endif /* CONFIG_NETFILTER */
5710
5711 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5712 static int selinux_disabled;
5713
5714 int selinux_disable(void)
5715 {
5716         extern void exit_sel_fs(void);
5717
5718         if (ss_initialized) {
5719                 /* Not permitted after initial policy load. */
5720                 return -EINVAL;
5721         }
5722
5723         if (selinux_disabled) {
5724                 /* Only do this once. */
5725                 return -EINVAL;
5726         }
5727
5728         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5729
5730         selinux_disabled = 1;
5731         selinux_enabled = 0;
5732
5733         reset_security_ops();
5734
5735         /* Try to destroy the avc node cache */
5736         avc_disable();
5737
5738         /* Unregister netfilter hooks. */
5739         selinux_nf_ip_exit();
5740
5741         /* Unregister selinuxfs. */
5742         exit_sel_fs();
5743
5744         return 0;
5745 }
5746 #endif