e95004010c8b674bcf4ba774ebecc224f9dbf2fa
[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 XATTR_SELINUX_SUFFIX "selinux"
91 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
92
93 #define NUM_SEL_MNT_OPTS 5
94
95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96 extern struct security_operations *security_ops;
97
98 /* SECMARK reference count */
99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 int selinux_enforcing;
103
104 static int __init enforcing_setup(char *str)
105 {
106         unsigned long enforcing;
107         if (!strict_strtoul(str, 0, &enforcing))
108                 selinux_enforcing = enforcing ? 1 : 0;
109         return 1;
110 }
111 __setup("enforcing=", enforcing_setup);
112 #endif
113
114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117 static int __init selinux_enabled_setup(char *str)
118 {
119         unsigned long enabled;
120         if (!strict_strtoul(str, 0, &enabled))
121                 selinux_enabled = enabled ? 1 : 0;
122         return 1;
123 }
124 __setup("selinux=", selinux_enabled_setup);
125 #else
126 int selinux_enabled = 1;
127 #endif
128
129 static struct kmem_cache *sel_inode_cache;
130
131 /**
132  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133  *
134  * Description:
135  * This function checks the SECMARK reference counter to see if any SECMARK
136  * targets are currently configured, if the reference counter is greater than
137  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
138  * enabled, false (0) if SECMARK is disabled.
139  *
140  */
141 static int selinux_secmark_enabled(void)
142 {
143         return (atomic_read(&selinux_secmark_refcount) > 0);
144 }
145
146 /*
147  * initialise the security for the init task
148  */
149 static void cred_init_security(void)
150 {
151         struct cred *cred = (struct cred *) current->real_cred;
152         struct task_security_struct *tsec;
153
154         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
155         if (!tsec)
156                 panic("SELinux:  Failed to initialize initial task.\n");
157
158         tsec->osid = tsec->sid = SECINITSID_KERNEL;
159         cred->security = tsec;
160 }
161
162 /*
163  * get the security ID of a set of credentials
164  */
165 static inline u32 cred_sid(const struct cred *cred)
166 {
167         const struct task_security_struct *tsec;
168
169         tsec = cred->security;
170         return tsec->sid;
171 }
172
173 /*
174  * get the objective security ID of a task
175  */
176 static inline u32 task_sid(const struct task_struct *task)
177 {
178         u32 sid;
179
180         rcu_read_lock();
181         sid = cred_sid(__task_cred(task));
182         rcu_read_unlock();
183         return sid;
184 }
185
186 /*
187  * get the subjective security ID of the current task
188  */
189 static inline u32 current_sid(void)
190 {
191         const struct task_security_struct *tsec = current_cred()->security;
192
193         return tsec->sid;
194 }
195
196 /* Allocate and free functions for each kind of security blob. */
197
198 static int inode_alloc_security(struct inode *inode)
199 {
200         struct inode_security_struct *isec;
201         u32 sid = current_sid();
202
203         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
204         if (!isec)
205                 return -ENOMEM;
206
207         mutex_init(&isec->lock);
208         INIT_LIST_HEAD(&isec->list);
209         isec->inode = inode;
210         isec->sid = SECINITSID_UNLABELED;
211         isec->sclass = SECCLASS_FILE;
212         isec->task_sid = sid;
213         inode->i_security = isec;
214
215         return 0;
216 }
217
218 static void inode_free_security(struct inode *inode)
219 {
220         struct inode_security_struct *isec = inode->i_security;
221         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
222
223         spin_lock(&sbsec->isec_lock);
224         if (!list_empty(&isec->list))
225                 list_del_init(&isec->list);
226         spin_unlock(&sbsec->isec_lock);
227
228         inode->i_security = NULL;
229         kmem_cache_free(sel_inode_cache, isec);
230 }
231
232 static int file_alloc_security(struct file *file)
233 {
234         struct file_security_struct *fsec;
235         u32 sid = current_sid();
236
237         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
238         if (!fsec)
239                 return -ENOMEM;
240
241         fsec->sid = sid;
242         fsec->fown_sid = sid;
243         file->f_security = fsec;
244
245         return 0;
246 }
247
248 static void file_free_security(struct file *file)
249 {
250         struct file_security_struct *fsec = file->f_security;
251         file->f_security = NULL;
252         kfree(fsec);
253 }
254
255 static int superblock_alloc_security(struct super_block *sb)
256 {
257         struct superblock_security_struct *sbsec;
258
259         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
260         if (!sbsec)
261                 return -ENOMEM;
262
263         mutex_init(&sbsec->lock);
264         INIT_LIST_HEAD(&sbsec->isec_head);
265         spin_lock_init(&sbsec->isec_lock);
266         sbsec->sb = sb;
267         sbsec->sid = SECINITSID_UNLABELED;
268         sbsec->def_sid = SECINITSID_FILE;
269         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
270         sb->s_security = sbsec;
271
272         return 0;
273 }
274
275 static void superblock_free_security(struct super_block *sb)
276 {
277         struct superblock_security_struct *sbsec = sb->s_security;
278         sb->s_security = NULL;
279         kfree(sbsec);
280 }
281
282 /* The security server must be initialized before
283    any labeling or access decisions can be provided. */
284 extern int ss_initialized;
285
286 /* The file system's label must be initialized prior to use. */
287
288 static const char *labeling_behaviors[6] = {
289         "uses xattr",
290         "uses transition SIDs",
291         "uses task SIDs",
292         "uses genfs_contexts",
293         "not configured for labeling",
294         "uses mountpoint labeling",
295 };
296
297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
298
299 static inline int inode_doinit(struct inode *inode)
300 {
301         return inode_doinit_with_dentry(inode, NULL);
302 }
303
304 enum {
305         Opt_error = -1,
306         Opt_context = 1,
307         Opt_fscontext = 2,
308         Opt_defcontext = 3,
309         Opt_rootcontext = 4,
310         Opt_labelsupport = 5,
311 };
312
313 static const match_table_t tokens = {
314         {Opt_context, CONTEXT_STR "%s"},
315         {Opt_fscontext, FSCONTEXT_STR "%s"},
316         {Opt_defcontext, DEFCONTEXT_STR "%s"},
317         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
318         {Opt_labelsupport, LABELSUPP_STR},
319         {Opt_error, NULL},
320 };
321
322 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
323
324 static int may_context_mount_sb_relabel(u32 sid,
325                         struct superblock_security_struct *sbsec,
326                         const struct cred *cred)
327 {
328         const struct task_security_struct *tsec = cred->security;
329         int rc;
330
331         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
332                           FILESYSTEM__RELABELFROM, NULL);
333         if (rc)
334                 return rc;
335
336         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
337                           FILESYSTEM__RELABELTO, NULL);
338         return rc;
339 }
340
341 static int may_context_mount_inode_relabel(u32 sid,
342                         struct superblock_security_struct *sbsec,
343                         const struct cred *cred)
344 {
345         const struct task_security_struct *tsec = cred->security;
346         int rc;
347         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
348                           FILESYSTEM__RELABELFROM, NULL);
349         if (rc)
350                 return rc;
351
352         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
353                           FILESYSTEM__ASSOCIATE, NULL);
354         return rc;
355 }
356
357 static int sb_finish_set_opts(struct super_block *sb)
358 {
359         struct superblock_security_struct *sbsec = sb->s_security;
360         struct dentry *root = sb->s_root;
361         struct inode *root_inode = root->d_inode;
362         int rc = 0;
363
364         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
365                 /* Make sure that the xattr handler exists and that no
366                    error other than -ENODATA is returned by getxattr on
367                    the root directory.  -ENODATA is ok, as this may be
368                    the first boot of the SELinux kernel before we have
369                    assigned xattr values to the filesystem. */
370                 if (!root_inode->i_op->getxattr) {
371                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
372                                "xattr support\n", sb->s_id, sb->s_type->name);
373                         rc = -EOPNOTSUPP;
374                         goto out;
375                 }
376                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
377                 if (rc < 0 && rc != -ENODATA) {
378                         if (rc == -EOPNOTSUPP)
379                                 printk(KERN_WARNING "SELinux: (dev %s, type "
380                                        "%s) has no security xattr handler\n",
381                                        sb->s_id, sb->s_type->name);
382                         else
383                                 printk(KERN_WARNING "SELinux: (dev %s, type "
384                                        "%s) getxattr errno %d\n", sb->s_id,
385                                        sb->s_type->name, -rc);
386                         goto out;
387                 }
388         }
389
390         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
391
392         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
393                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
394                        sb->s_id, sb->s_type->name);
395         else
396                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
397                        sb->s_id, sb->s_type->name,
398                        labeling_behaviors[sbsec->behavior-1]);
399
400         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
401             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
402             sbsec->behavior == SECURITY_FS_USE_NONE ||
403             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404                 sbsec->flags &= ~SE_SBLABELSUPP;
405
406         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
407         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
408                 sbsec->flags |= SE_SBLABELSUPP;
409
410         /* Initialize the root inode. */
411         rc = inode_doinit_with_dentry(root_inode, root);
412
413         /* Initialize any other inodes associated with the superblock, e.g.
414            inodes created prior to initial policy load or inodes created
415            during get_sb by a pseudo filesystem that directly
416            populates itself. */
417         spin_lock(&sbsec->isec_lock);
418 next_inode:
419         if (!list_empty(&sbsec->isec_head)) {
420                 struct inode_security_struct *isec =
421                                 list_entry(sbsec->isec_head.next,
422                                            struct inode_security_struct, list);
423                 struct inode *inode = isec->inode;
424                 spin_unlock(&sbsec->isec_lock);
425                 inode = igrab(inode);
426                 if (inode) {
427                         if (!IS_PRIVATE(inode))
428                                 inode_doinit(inode);
429                         iput(inode);
430                 }
431                 spin_lock(&sbsec->isec_lock);
432                 list_del_init(&isec->list);
433                 goto next_inode;
434         }
435         spin_unlock(&sbsec->isec_lock);
436 out:
437         return rc;
438 }
439
440 /*
441  * This function should allow an FS to ask what it's mount security
442  * options were so it can use those later for submounts, displaying
443  * mount options, or whatever.
444  */
445 static int selinux_get_mnt_opts(const struct super_block *sb,
446                                 struct security_mnt_opts *opts)
447 {
448         int rc = 0, i;
449         struct superblock_security_struct *sbsec = sb->s_security;
450         char *context = NULL;
451         u32 len;
452         char tmp;
453
454         security_init_mnt_opts(opts);
455
456         if (!(sbsec->flags & SE_SBINITIALIZED))
457                 return -EINVAL;
458
459         if (!ss_initialized)
460                 return -EINVAL;
461
462         tmp = sbsec->flags & SE_MNTMASK;
463         /* count the number of mount options for this sb */
464         for (i = 0; i < 8; i++) {
465                 if (tmp & 0x01)
466                         opts->num_mnt_opts++;
467                 tmp >>= 1;
468         }
469         /* Check if the Label support flag is set */
470         if (sbsec->flags & SE_SBLABELSUPP)
471                 opts->num_mnt_opts++;
472
473         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
474         if (!opts->mnt_opts) {
475                 rc = -ENOMEM;
476                 goto out_free;
477         }
478
479         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
480         if (!opts->mnt_opts_flags) {
481                 rc = -ENOMEM;
482                 goto out_free;
483         }
484
485         i = 0;
486         if (sbsec->flags & FSCONTEXT_MNT) {
487                 rc = security_sid_to_context(sbsec->sid, &context, &len);
488                 if (rc)
489                         goto out_free;
490                 opts->mnt_opts[i] = context;
491                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
492         }
493         if (sbsec->flags & CONTEXT_MNT) {
494                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
495                 if (rc)
496                         goto out_free;
497                 opts->mnt_opts[i] = context;
498                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
499         }
500         if (sbsec->flags & DEFCONTEXT_MNT) {
501                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
502                 if (rc)
503                         goto out_free;
504                 opts->mnt_opts[i] = context;
505                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
506         }
507         if (sbsec->flags & ROOTCONTEXT_MNT) {
508                 struct inode *root = sbsec->sb->s_root->d_inode;
509                 struct inode_security_struct *isec = root->i_security;
510
511                 rc = security_sid_to_context(isec->sid, &context, &len);
512                 if (rc)
513                         goto out_free;
514                 opts->mnt_opts[i] = context;
515                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
516         }
517         if (sbsec->flags & SE_SBLABELSUPP) {
518                 opts->mnt_opts[i] = NULL;
519                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
520         }
521
522         BUG_ON(i != opts->num_mnt_opts);
523
524         return 0;
525
526 out_free:
527         security_free_mnt_opts(opts);
528         return rc;
529 }
530
531 static int bad_option(struct superblock_security_struct *sbsec, char flag,
532                       u32 old_sid, u32 new_sid)
533 {
534         char mnt_flags = sbsec->flags & SE_MNTMASK;
535
536         /* check if the old mount command had the same options */
537         if (sbsec->flags & SE_SBINITIALIZED)
538                 if (!(sbsec->flags & flag) ||
539                     (old_sid != new_sid))
540                         return 1;
541
542         /* check if we were passed the same options twice,
543          * aka someone passed context=a,context=b
544          */
545         if (!(sbsec->flags & SE_SBINITIALIZED))
546                 if (mnt_flags & flag)
547                         return 1;
548         return 0;
549 }
550
551 /*
552  * Allow filesystems with binary mount data to explicitly set mount point
553  * labeling information.
554  */
555 static int selinux_set_mnt_opts(struct super_block *sb,
556                                 struct security_mnt_opts *opts)
557 {
558         const struct cred *cred = current_cred();
559         int rc = 0, i;
560         struct superblock_security_struct *sbsec = sb->s_security;
561         const char *name = sb->s_type->name;
562         struct inode *inode = sbsec->sb->s_root->d_inode;
563         struct inode_security_struct *root_isec = inode->i_security;
564         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
565         u32 defcontext_sid = 0;
566         char **mount_options = opts->mnt_opts;
567         int *flags = opts->mnt_opts_flags;
568         int num_opts = opts->num_mnt_opts;
569
570         mutex_lock(&sbsec->lock);
571
572         if (!ss_initialized) {
573                 if (!num_opts) {
574                         /* Defer initialization until selinux_complete_init,
575                            after the initial policy is loaded and the security
576                            server is ready to handle calls. */
577                         goto out;
578                 }
579                 rc = -EINVAL;
580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581                         "before the security server is initialized\n");
582                 goto out;
583         }
584
585         /*
586          * Binary mount data FS will come through this function twice.  Once
587          * from an explicit call and once from the generic calls from the vfs.
588          * Since the generic VFS calls will not contain any security mount data
589          * we need to skip the double mount verification.
590          *
591          * This does open a hole in which we will not notice if the first
592          * mount using this sb set explict options and a second mount using
593          * this sb does not set any security options.  (The first options
594          * will be used for both mounts)
595          */
596         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597             && (num_opts == 0))
598                 goto out;
599
600         /*
601          * parse the mount options, check if they are valid sids.
602          * also check if someone is trying to mount the same sb more
603          * than once with different security options.
604          */
605         for (i = 0; i < num_opts; i++) {
606                 u32 sid;
607
608                 if (flags[i] == SE_SBLABELSUPP)
609                         continue;
610                 rc = security_context_to_sid(mount_options[i],
611                                              strlen(mount_options[i]), &sid);
612                 if (rc) {
613                         printk(KERN_WARNING "SELinux: security_context_to_sid"
614                                "(%s) failed for (dev %s, type %s) errno=%d\n",
615                                mount_options[i], sb->s_id, name, rc);
616                         goto out;
617                 }
618                 switch (flags[i]) {
619                 case FSCONTEXT_MNT:
620                         fscontext_sid = sid;
621
622                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
623                                         fscontext_sid))
624                                 goto out_double_mount;
625
626                         sbsec->flags |= FSCONTEXT_MNT;
627                         break;
628                 case CONTEXT_MNT:
629                         context_sid = sid;
630
631                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
632                                         context_sid))
633                                 goto out_double_mount;
634
635                         sbsec->flags |= CONTEXT_MNT;
636                         break;
637                 case ROOTCONTEXT_MNT:
638                         rootcontext_sid = sid;
639
640                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
641                                         rootcontext_sid))
642                                 goto out_double_mount;
643
644                         sbsec->flags |= ROOTCONTEXT_MNT;
645
646                         break;
647                 case DEFCONTEXT_MNT:
648                         defcontext_sid = sid;
649
650                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
651                                         defcontext_sid))
652                                 goto out_double_mount;
653
654                         sbsec->flags |= DEFCONTEXT_MNT;
655
656                         break;
657                 default:
658                         rc = -EINVAL;
659                         goto out;
660                 }
661         }
662
663         if (sbsec->flags & SE_SBINITIALIZED) {
664                 /* previously mounted with options, but not on this attempt? */
665                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666                         goto out_double_mount;
667                 rc = 0;
668                 goto out;
669         }
670
671         if (strcmp(sb->s_type->name, "proc") == 0)
672                 sbsec->flags |= SE_SBPROC;
673
674         /* Determine the labeling behavior to use for this filesystem type. */
675         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676         if (rc) {
677                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678                        __func__, sb->s_type->name, rc);
679                 goto out;
680         }
681
682         /* sets the context of the superblock for the fs being mounted. */
683         if (fscontext_sid) {
684                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
685                 if (rc)
686                         goto out;
687
688                 sbsec->sid = fscontext_sid;
689         }
690
691         /*
692          * Switch to using mount point labeling behavior.
693          * sets the label used on all file below the mountpoint, and will set
694          * the superblock context if not already set.
695          */
696         if (context_sid) {
697                 if (!fscontext_sid) {
698                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
699                                                           cred);
700                         if (rc)
701                                 goto out;
702                         sbsec->sid = context_sid;
703                 } else {
704                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
705                                                              cred);
706                         if (rc)
707                                 goto out;
708                 }
709                 if (!rootcontext_sid)
710                         rootcontext_sid = context_sid;
711
712                 sbsec->mntpoint_sid = context_sid;
713                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
714         }
715
716         if (rootcontext_sid) {
717                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
718                                                      cred);
719                 if (rc)
720                         goto out;
721
722                 root_isec->sid = rootcontext_sid;
723                 root_isec->initialized = 1;
724         }
725
726         if (defcontext_sid) {
727                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
728                         rc = -EINVAL;
729                         printk(KERN_WARNING "SELinux: defcontext option is "
730                                "invalid for this filesystem type\n");
731                         goto out;
732                 }
733
734                 if (defcontext_sid != sbsec->def_sid) {
735                         rc = may_context_mount_inode_relabel(defcontext_sid,
736                                                              sbsec, cred);
737                         if (rc)
738                                 goto out;
739                 }
740
741                 sbsec->def_sid = defcontext_sid;
742         }
743
744         rc = sb_finish_set_opts(sb);
745 out:
746         mutex_unlock(&sbsec->lock);
747         return rc;
748 out_double_mount:
749         rc = -EINVAL;
750         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
751                "security settings for (dev %s, type %s)\n", sb->s_id, name);
752         goto out;
753 }
754
755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
756                                         struct super_block *newsb)
757 {
758         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
759         struct superblock_security_struct *newsbsec = newsb->s_security;
760
761         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
762         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
763         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
764
765         /*
766          * if the parent was able to be mounted it clearly had no special lsm
767          * mount options.  thus we can safely deal with this superblock later
768          */
769         if (!ss_initialized)
770                 return;
771
772         /* how can we clone if the old one wasn't set up?? */
773         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774
775         /* if fs is reusing a sb, just let its options stand... */
776         if (newsbsec->flags & SE_SBINITIALIZED)
777                 return;
778
779         mutex_lock(&newsbsec->lock);
780
781         newsbsec->flags = oldsbsec->flags;
782
783         newsbsec->sid = oldsbsec->sid;
784         newsbsec->def_sid = oldsbsec->def_sid;
785         newsbsec->behavior = oldsbsec->behavior;
786
787         if (set_context) {
788                 u32 sid = oldsbsec->mntpoint_sid;
789
790                 if (!set_fscontext)
791                         newsbsec->sid = sid;
792                 if (!set_rootcontext) {
793                         struct inode *newinode = newsb->s_root->d_inode;
794                         struct inode_security_struct *newisec = newinode->i_security;
795                         newisec->sid = sid;
796                 }
797                 newsbsec->mntpoint_sid = sid;
798         }
799         if (set_rootcontext) {
800                 const struct inode *oldinode = oldsb->s_root->d_inode;
801                 const struct inode_security_struct *oldisec = oldinode->i_security;
802                 struct inode *newinode = newsb->s_root->d_inode;
803                 struct inode_security_struct *newisec = newinode->i_security;
804
805                 newisec->sid = oldisec->sid;
806         }
807
808         sb_finish_set_opts(newsb);
809         mutex_unlock(&newsbsec->lock);
810 }
811
812 static int selinux_parse_opts_str(char *options,
813                                   struct security_mnt_opts *opts)
814 {
815         char *p;
816         char *context = NULL, *defcontext = NULL;
817         char *fscontext = NULL, *rootcontext = NULL;
818         int rc, num_mnt_opts = 0;
819
820         opts->num_mnt_opts = 0;
821
822         /* Standard string-based options. */
823         while ((p = strsep(&options, "|")) != NULL) {
824                 int token;
825                 substring_t args[MAX_OPT_ARGS];
826
827                 if (!*p)
828                         continue;
829
830                 token = match_token(p, tokens, args);
831
832                 switch (token) {
833                 case Opt_context:
834                         if (context || defcontext) {
835                                 rc = -EINVAL;
836                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
837                                 goto out_err;
838                         }
839                         context = match_strdup(&args[0]);
840                         if (!context) {
841                                 rc = -ENOMEM;
842                                 goto out_err;
843                         }
844                         break;
845
846                 case Opt_fscontext:
847                         if (fscontext) {
848                                 rc = -EINVAL;
849                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
850                                 goto out_err;
851                         }
852                         fscontext = match_strdup(&args[0]);
853                         if (!fscontext) {
854                                 rc = -ENOMEM;
855                                 goto out_err;
856                         }
857                         break;
858
859                 case Opt_rootcontext:
860                         if (rootcontext) {
861                                 rc = -EINVAL;
862                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
863                                 goto out_err;
864                         }
865                         rootcontext = match_strdup(&args[0]);
866                         if (!rootcontext) {
867                                 rc = -ENOMEM;
868                                 goto out_err;
869                         }
870                         break;
871
872                 case Opt_defcontext:
873                         if (context || defcontext) {
874                                 rc = -EINVAL;
875                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
876                                 goto out_err;
877                         }
878                         defcontext = match_strdup(&args[0]);
879                         if (!defcontext) {
880                                 rc = -ENOMEM;
881                                 goto out_err;
882                         }
883                         break;
884                 case Opt_labelsupport:
885                         break;
886                 default:
887                         rc = -EINVAL;
888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
889                         goto out_err;
890
891                 }
892         }
893
894         rc = -ENOMEM;
895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896         if (!opts->mnt_opts)
897                 goto out_err;
898
899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900         if (!opts->mnt_opts_flags) {
901                 kfree(opts->mnt_opts);
902                 goto out_err;
903         }
904
905         if (fscontext) {
906                 opts->mnt_opts[num_mnt_opts] = fscontext;
907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908         }
909         if (context) {
910                 opts->mnt_opts[num_mnt_opts] = context;
911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912         }
913         if (rootcontext) {
914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916         }
917         if (defcontext) {
918                 opts->mnt_opts[num_mnt_opts] = defcontext;
919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920         }
921
922         opts->num_mnt_opts = num_mnt_opts;
923         return 0;
924
925 out_err:
926         kfree(context);
927         kfree(defcontext);
928         kfree(fscontext);
929         kfree(rootcontext);
930         return rc;
931 }
932 /*
933  * string mount options parsing and call set the sbsec
934  */
935 static int superblock_doinit(struct super_block *sb, void *data)
936 {
937         int rc = 0;
938         char *options = data;
939         struct security_mnt_opts opts;
940
941         security_init_mnt_opts(&opts);
942
943         if (!data)
944                 goto out;
945
946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948         rc = selinux_parse_opts_str(options, &opts);
949         if (rc)
950                 goto out_err;
951
952 out:
953         rc = selinux_set_mnt_opts(sb, &opts);
954
955 out_err:
956         security_free_mnt_opts(&opts);
957         return rc;
958 }
959
960 static void selinux_write_opts(struct seq_file *m,
961                                struct security_mnt_opts *opts)
962 {
963         int i;
964         char *prefix;
965
966         for (i = 0; i < opts->num_mnt_opts; i++) {
967                 char *has_comma;
968
969                 if (opts->mnt_opts[i])
970                         has_comma = strchr(opts->mnt_opts[i], ',');
971                 else
972                         has_comma = NULL;
973
974                 switch (opts->mnt_opts_flags[i]) {
975                 case CONTEXT_MNT:
976                         prefix = CONTEXT_STR;
977                         break;
978                 case FSCONTEXT_MNT:
979                         prefix = FSCONTEXT_STR;
980                         break;
981                 case ROOTCONTEXT_MNT:
982                         prefix = ROOTCONTEXT_STR;
983                         break;
984                 case DEFCONTEXT_MNT:
985                         prefix = DEFCONTEXT_STR;
986                         break;
987                 case SE_SBLABELSUPP:
988                         seq_putc(m, ',');
989                         seq_puts(m, LABELSUPP_STR);
990                         continue;
991                 default:
992                         BUG();
993                 };
994                 /* we need a comma before each option */
995                 seq_putc(m, ',');
996                 seq_puts(m, prefix);
997                 if (has_comma)
998                         seq_putc(m, '\"');
999                 seq_puts(m, opts->mnt_opts[i]);
1000                 if (has_comma)
1001                         seq_putc(m, '\"');
1002         }
1003 }
1004
1005 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1006 {
1007         struct security_mnt_opts opts;
1008         int rc;
1009
1010         rc = selinux_get_mnt_opts(sb, &opts);
1011         if (rc) {
1012                 /* before policy load we may get EINVAL, don't show anything */
1013                 if (rc == -EINVAL)
1014                         rc = 0;
1015                 return rc;
1016         }
1017
1018         selinux_write_opts(m, &opts);
1019
1020         security_free_mnt_opts(&opts);
1021
1022         return rc;
1023 }
1024
1025 static inline u16 inode_mode_to_security_class(umode_t mode)
1026 {
1027         switch (mode & S_IFMT) {
1028         case S_IFSOCK:
1029                 return SECCLASS_SOCK_FILE;
1030         case S_IFLNK:
1031                 return SECCLASS_LNK_FILE;
1032         case S_IFREG:
1033                 return SECCLASS_FILE;
1034         case S_IFBLK:
1035                 return SECCLASS_BLK_FILE;
1036         case S_IFDIR:
1037                 return SECCLASS_DIR;
1038         case S_IFCHR:
1039                 return SECCLASS_CHR_FILE;
1040         case S_IFIFO:
1041                 return SECCLASS_FIFO_FILE;
1042
1043         }
1044
1045         return SECCLASS_FILE;
1046 }
1047
1048 static inline int default_protocol_stream(int protocol)
1049 {
1050         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1051 }
1052
1053 static inline int default_protocol_dgram(int protocol)
1054 {
1055         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1056 }
1057
1058 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1059 {
1060         switch (family) {
1061         case PF_UNIX:
1062                 switch (type) {
1063                 case SOCK_STREAM:
1064                 case SOCK_SEQPACKET:
1065                         return SECCLASS_UNIX_STREAM_SOCKET;
1066                 case SOCK_DGRAM:
1067                         return SECCLASS_UNIX_DGRAM_SOCKET;
1068                 }
1069                 break;
1070         case PF_INET:
1071         case PF_INET6:
1072                 switch (type) {
1073                 case SOCK_STREAM:
1074                         if (default_protocol_stream(protocol))
1075                                 return SECCLASS_TCP_SOCKET;
1076                         else
1077                                 return SECCLASS_RAWIP_SOCKET;
1078                 case SOCK_DGRAM:
1079                         if (default_protocol_dgram(protocol))
1080                                 return SECCLASS_UDP_SOCKET;
1081                         else
1082                                 return SECCLASS_RAWIP_SOCKET;
1083                 case SOCK_DCCP:
1084                         return SECCLASS_DCCP_SOCKET;
1085                 default:
1086                         return SECCLASS_RAWIP_SOCKET;
1087                 }
1088                 break;
1089         case PF_NETLINK:
1090                 switch (protocol) {
1091                 case NETLINK_ROUTE:
1092                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1093                 case NETLINK_FIREWALL:
1094                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1095                 case NETLINK_INET_DIAG:
1096                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1097                 case NETLINK_NFLOG:
1098                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1099                 case NETLINK_XFRM:
1100                         return SECCLASS_NETLINK_XFRM_SOCKET;
1101                 case NETLINK_SELINUX:
1102                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1103                 case NETLINK_AUDIT:
1104                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1105                 case NETLINK_IP6_FW:
1106                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1107                 case NETLINK_DNRTMSG:
1108                         return SECCLASS_NETLINK_DNRT_SOCKET;
1109                 case NETLINK_KOBJECT_UEVENT:
1110                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1111                 default:
1112                         return SECCLASS_NETLINK_SOCKET;
1113                 }
1114         case PF_PACKET:
1115                 return SECCLASS_PACKET_SOCKET;
1116         case PF_KEY:
1117                 return SECCLASS_KEY_SOCKET;
1118         case PF_APPLETALK:
1119                 return SECCLASS_APPLETALK_SOCKET;
1120         }
1121
1122         return SECCLASS_SOCKET;
1123 }
1124
1125 #ifdef CONFIG_PROC_FS
1126 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1127                                 u16 tclass,
1128                                 u32 *sid)
1129 {
1130         int buflen, rc;
1131         char *buffer, *path, *end;
1132
1133         buffer = (char *)__get_free_page(GFP_KERNEL);
1134         if (!buffer)
1135                 return -ENOMEM;
1136
1137         buflen = PAGE_SIZE;
1138         end = buffer+buflen;
1139         *--end = '\0';
1140         buflen--;
1141         path = end-1;
1142         *path = '/';
1143         while (de && de != de->parent) {
1144                 buflen -= de->namelen + 1;
1145                 if (buflen < 0)
1146                         break;
1147                 end -= de->namelen;
1148                 memcpy(end, de->name, de->namelen);
1149                 *--end = '/';
1150                 path = end;
1151                 de = de->parent;
1152         }
1153         rc = security_genfs_sid("proc", path, tclass, sid);
1154         free_page((unsigned long)buffer);
1155         return rc;
1156 }
1157 #else
1158 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1159                                 u16 tclass,
1160                                 u32 *sid)
1161 {
1162         return -EINVAL;
1163 }
1164 #endif
1165
1166 /* The inode's security attributes must be initialized before first use. */
1167 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1168 {
1169         struct superblock_security_struct *sbsec = NULL;
1170         struct inode_security_struct *isec = inode->i_security;
1171         u32 sid;
1172         struct dentry *dentry;
1173 #define INITCONTEXTLEN 255
1174         char *context = NULL;
1175         unsigned len = 0;
1176         int rc = 0;
1177
1178         if (isec->initialized)
1179                 goto out;
1180
1181         mutex_lock(&isec->lock);
1182         if (isec->initialized)
1183                 goto out_unlock;
1184
1185         sbsec = inode->i_sb->s_security;
1186         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1187                 /* Defer initialization until selinux_complete_init,
1188                    after the initial policy is loaded and the security
1189                    server is ready to handle calls. */
1190                 spin_lock(&sbsec->isec_lock);
1191                 if (list_empty(&isec->list))
1192                         list_add(&isec->list, &sbsec->isec_head);
1193                 spin_unlock(&sbsec->isec_lock);
1194                 goto out_unlock;
1195         }
1196
1197         switch (sbsec->behavior) {
1198         case SECURITY_FS_USE_XATTR:
1199                 if (!inode->i_op->getxattr) {
1200                         isec->sid = sbsec->def_sid;
1201                         break;
1202                 }
1203
1204                 /* Need a dentry, since the xattr API requires one.
1205                    Life would be simpler if we could just pass the inode. */
1206                 if (opt_dentry) {
1207                         /* Called from d_instantiate or d_splice_alias. */
1208                         dentry = dget(opt_dentry);
1209                 } else {
1210                         /* Called from selinux_complete_init, try to find a dentry. */
1211                         dentry = d_find_alias(inode);
1212                 }
1213                 if (!dentry) {
1214                         /*
1215                          * this is can be hit on boot when a file is accessed
1216                          * before the policy is loaded.  When we load policy we
1217                          * may find inodes that have no dentry on the
1218                          * sbsec->isec_head list.  No reason to complain as these
1219                          * will get fixed up the next time we go through
1220                          * inode_doinit with a dentry, before these inodes could
1221                          * be used again by userspace.
1222                          */
1223                         goto out_unlock;
1224                 }
1225
1226                 len = INITCONTEXTLEN;
1227                 context = kmalloc(len+1, GFP_NOFS);
1228                 if (!context) {
1229                         rc = -ENOMEM;
1230                         dput(dentry);
1231                         goto out_unlock;
1232                 }
1233                 context[len] = '\0';
1234                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1235                                            context, len);
1236                 if (rc == -ERANGE) {
1237                         kfree(context);
1238
1239                         /* Need a larger buffer.  Query for the right size. */
1240                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1241                                                    NULL, 0);
1242                         if (rc < 0) {
1243                                 dput(dentry);
1244                                 goto out_unlock;
1245                         }
1246                         len = rc;
1247                         context = kmalloc(len+1, GFP_NOFS);
1248                         if (!context) {
1249                                 rc = -ENOMEM;
1250                                 dput(dentry);
1251                                 goto out_unlock;
1252                         }
1253                         context[len] = '\0';
1254                         rc = inode->i_op->getxattr(dentry,
1255                                                    XATTR_NAME_SELINUX,
1256                                                    context, len);
1257                 }
1258                 dput(dentry);
1259                 if (rc < 0) {
1260                         if (rc != -ENODATA) {
1261                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1262                                        "%d for dev=%s ino=%ld\n", __func__,
1263                                        -rc, inode->i_sb->s_id, inode->i_ino);
1264                                 kfree(context);
1265                                 goto out_unlock;
1266                         }
1267                         /* Map ENODATA to the default file SID */
1268                         sid = sbsec->def_sid;
1269                         rc = 0;
1270                 } else {
1271                         rc = security_context_to_sid_default(context, rc, &sid,
1272                                                              sbsec->def_sid,
1273                                                              GFP_NOFS);
1274                         if (rc) {
1275                                 char *dev = inode->i_sb->s_id;
1276                                 unsigned long ino = inode->i_ino;
1277
1278                                 if (rc == -EINVAL) {
1279                                         if (printk_ratelimit())
1280                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1281                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1282                                                         "filesystem in question.\n", ino, dev, context);
1283                                 } else {
1284                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1285                                                "returned %d for dev=%s ino=%ld\n",
1286                                                __func__, context, -rc, dev, ino);
1287                                 }
1288                                 kfree(context);
1289                                 /* Leave with the unlabeled SID */
1290                                 rc = 0;
1291                                 break;
1292                         }
1293                 }
1294                 kfree(context);
1295                 isec->sid = sid;
1296                 break;
1297         case SECURITY_FS_USE_TASK:
1298                 isec->sid = isec->task_sid;
1299                 break;
1300         case SECURITY_FS_USE_TRANS:
1301                 /* Default to the fs SID. */
1302                 isec->sid = sbsec->sid;
1303
1304                 /* Try to obtain a transition SID. */
1305                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1306                 rc = security_transition_sid(isec->task_sid,
1307                                              sbsec->sid,
1308                                              isec->sclass,
1309                                              &sid);
1310                 if (rc)
1311                         goto out_unlock;
1312                 isec->sid = sid;
1313                 break;
1314         case SECURITY_FS_USE_MNTPOINT:
1315                 isec->sid = sbsec->mntpoint_sid;
1316                 break;
1317         default:
1318                 /* Default to the fs superblock SID. */
1319                 isec->sid = sbsec->sid;
1320
1321                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1322                         struct proc_inode *proci = PROC_I(inode);
1323                         if (proci->pde) {
1324                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1325                                 rc = selinux_proc_get_sid(proci->pde,
1326                                                           isec->sclass,
1327                                                           &sid);
1328                                 if (rc)
1329                                         goto out_unlock;
1330                                 isec->sid = sid;
1331                         }
1332                 }
1333                 break;
1334         }
1335
1336         isec->initialized = 1;
1337
1338 out_unlock:
1339         mutex_unlock(&isec->lock);
1340 out:
1341         if (isec->sclass == SECCLASS_FILE)
1342                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1343         return rc;
1344 }
1345
1346 /* Convert a Linux signal to an access vector. */
1347 static inline u32 signal_to_av(int sig)
1348 {
1349         u32 perm = 0;
1350
1351         switch (sig) {
1352         case SIGCHLD:
1353                 /* Commonly granted from child to parent. */
1354                 perm = PROCESS__SIGCHLD;
1355                 break;
1356         case SIGKILL:
1357                 /* Cannot be caught or ignored */
1358                 perm = PROCESS__SIGKILL;
1359                 break;
1360         case SIGSTOP:
1361                 /* Cannot be caught or ignored */
1362                 perm = PROCESS__SIGSTOP;
1363                 break;
1364         default:
1365                 /* All other signals. */
1366                 perm = PROCESS__SIGNAL;
1367                 break;
1368         }
1369
1370         return perm;
1371 }
1372
1373 /*
1374  * Check permission between a pair of credentials
1375  * fork check, ptrace check, etc.
1376  */
1377 static int cred_has_perm(const struct cred *actor,
1378                          const struct cred *target,
1379                          u32 perms)
1380 {
1381         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1382
1383         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1384 }
1385
1386 /*
1387  * Check permission between a pair of tasks, e.g. signal checks,
1388  * fork check, ptrace check, etc.
1389  * tsk1 is the actor and tsk2 is the target
1390  * - this uses the default subjective creds of tsk1
1391  */
1392 static int task_has_perm(const struct task_struct *tsk1,
1393                          const struct task_struct *tsk2,
1394                          u32 perms)
1395 {
1396         const struct task_security_struct *__tsec1, *__tsec2;
1397         u32 sid1, sid2;
1398
1399         rcu_read_lock();
1400         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1401         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1402         rcu_read_unlock();
1403         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1404 }
1405
1406 /*
1407  * Check permission between current and another task, e.g. signal checks,
1408  * fork check, ptrace check, etc.
1409  * current is the actor and tsk2 is the target
1410  * - this uses current's subjective creds
1411  */
1412 static int current_has_perm(const struct task_struct *tsk,
1413                             u32 perms)
1414 {
1415         u32 sid, tsid;
1416
1417         sid = current_sid();
1418         tsid = task_sid(tsk);
1419         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1420 }
1421
1422 #if CAP_LAST_CAP > 63
1423 #error Fix SELinux to handle capabilities > 63.
1424 #endif
1425
1426 /* Check whether a task is allowed to use a capability. */
1427 static int task_has_capability(struct task_struct *tsk,
1428                                const struct cred *cred,
1429                                int cap, int audit)
1430 {
1431         struct common_audit_data ad;
1432         struct av_decision avd;
1433         u16 sclass;
1434         u32 sid = cred_sid(cred);
1435         u32 av = CAP_TO_MASK(cap);
1436         int rc;
1437
1438         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1439         ad.tsk = tsk;
1440         ad.u.cap = cap;
1441
1442         switch (CAP_TO_INDEX(cap)) {
1443         case 0:
1444                 sclass = SECCLASS_CAPABILITY;
1445                 break;
1446         case 1:
1447                 sclass = SECCLASS_CAPABILITY2;
1448                 break;
1449         default:
1450                 printk(KERN_ERR
1451                        "SELinux:  out of range capability %d\n", cap);
1452                 BUG();
1453         }
1454
1455         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1456         if (audit == SECURITY_CAP_AUDIT)
1457                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1458         return rc;
1459 }
1460
1461 /* Check whether a task is allowed to use a system operation. */
1462 static int task_has_system(struct task_struct *tsk,
1463                            u32 perms)
1464 {
1465         u32 sid = task_sid(tsk);
1466
1467         return avc_has_perm(sid, SECINITSID_KERNEL,
1468                             SECCLASS_SYSTEM, perms, NULL);
1469 }
1470
1471 /* Check whether a task has a particular permission to an inode.
1472    The 'adp' parameter is optional and allows other audit
1473    data to be passed (e.g. the dentry). */
1474 static int inode_has_perm(const struct cred *cred,
1475                           struct inode *inode,
1476                           u32 perms,
1477                           struct common_audit_data *adp)
1478 {
1479         struct inode_security_struct *isec;
1480         struct common_audit_data ad;
1481         u32 sid;
1482
1483         validate_creds(cred);
1484
1485         if (unlikely(IS_PRIVATE(inode)))
1486                 return 0;
1487
1488         sid = cred_sid(cred);
1489         isec = inode->i_security;
1490
1491         if (!adp) {
1492                 adp = &ad;
1493                 COMMON_AUDIT_DATA_INIT(&ad, FS);
1494                 ad.u.fs.inode = inode;
1495         }
1496
1497         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1498 }
1499
1500 /* Same as inode_has_perm, but pass explicit audit data containing
1501    the dentry to help the auditing code to more easily generate the
1502    pathname if needed. */
1503 static inline int dentry_has_perm(const struct cred *cred,
1504                                   struct vfsmount *mnt,
1505                                   struct dentry *dentry,
1506                                   u32 av)
1507 {
1508         struct inode *inode = dentry->d_inode;
1509         struct common_audit_data ad;
1510
1511         COMMON_AUDIT_DATA_INIT(&ad, FS);
1512         ad.u.fs.path.mnt = mnt;
1513         ad.u.fs.path.dentry = dentry;
1514         return inode_has_perm(cred, inode, av, &ad);
1515 }
1516
1517 /* Check whether a task can use an open file descriptor to
1518    access an inode in a given way.  Check access to the
1519    descriptor itself, and then use dentry_has_perm to
1520    check a particular permission to the file.
1521    Access to the descriptor is implicitly granted if it
1522    has the same SID as the process.  If av is zero, then
1523    access to the file is not checked, e.g. for cases
1524    where only the descriptor is affected like seek. */
1525 static int file_has_perm(const struct cred *cred,
1526                          struct file *file,
1527                          u32 av)
1528 {
1529         struct file_security_struct *fsec = file->f_security;
1530         struct inode *inode = file->f_path.dentry->d_inode;
1531         struct common_audit_data ad;
1532         u32 sid = cred_sid(cred);
1533         int rc;
1534
1535         COMMON_AUDIT_DATA_INIT(&ad, FS);
1536         ad.u.fs.path = file->f_path;
1537
1538         if (sid != fsec->sid) {
1539                 rc = avc_has_perm(sid, fsec->sid,
1540                                   SECCLASS_FD,
1541                                   FD__USE,
1542                                   &ad);
1543                 if (rc)
1544                         goto out;
1545         }
1546
1547         /* av is zero if only checking access to the descriptor. */
1548         rc = 0;
1549         if (av)
1550                 rc = inode_has_perm(cred, inode, av, &ad);
1551
1552 out:
1553         return rc;
1554 }
1555
1556 /* Check whether a task can create a file. */
1557 static int may_create(struct inode *dir,
1558                       struct dentry *dentry,
1559                       u16 tclass)
1560 {
1561         const struct cred *cred = current_cred();
1562         const struct task_security_struct *tsec = cred->security;
1563         struct inode_security_struct *dsec;
1564         struct superblock_security_struct *sbsec;
1565         u32 sid, newsid;
1566         struct common_audit_data ad;
1567         int rc;
1568
1569         dsec = dir->i_security;
1570         sbsec = dir->i_sb->s_security;
1571
1572         sid = tsec->sid;
1573         newsid = tsec->create_sid;
1574
1575         COMMON_AUDIT_DATA_INIT(&ad, FS);
1576         ad.u.fs.path.dentry = dentry;
1577
1578         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1579                           DIR__ADD_NAME | DIR__SEARCH,
1580                           &ad);
1581         if (rc)
1582                 return rc;
1583
1584         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1585                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1586                 if (rc)
1587                         return rc;
1588         }
1589
1590         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1591         if (rc)
1592                 return rc;
1593
1594         return avc_has_perm(newsid, sbsec->sid,
1595                             SECCLASS_FILESYSTEM,
1596                             FILESYSTEM__ASSOCIATE, &ad);
1597 }
1598
1599 /* Check whether a task can create a key. */
1600 static int may_create_key(u32 ksid,
1601                           struct task_struct *ctx)
1602 {
1603         u32 sid = task_sid(ctx);
1604
1605         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1606 }
1607
1608 #define MAY_LINK        0
1609 #define MAY_UNLINK      1
1610 #define MAY_RMDIR       2
1611
1612 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1613 static int may_link(struct inode *dir,
1614                     struct dentry *dentry,
1615                     int kind)
1616
1617 {
1618         struct inode_security_struct *dsec, *isec;
1619         struct common_audit_data ad;
1620         u32 sid = current_sid();
1621         u32 av;
1622         int rc;
1623
1624         dsec = dir->i_security;
1625         isec = dentry->d_inode->i_security;
1626
1627         COMMON_AUDIT_DATA_INIT(&ad, FS);
1628         ad.u.fs.path.dentry = dentry;
1629
1630         av = DIR__SEARCH;
1631         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1632         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1633         if (rc)
1634                 return rc;
1635
1636         switch (kind) {
1637         case MAY_LINK:
1638                 av = FILE__LINK;
1639                 break;
1640         case MAY_UNLINK:
1641                 av = FILE__UNLINK;
1642                 break;
1643         case MAY_RMDIR:
1644                 av = DIR__RMDIR;
1645                 break;
1646         default:
1647                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1648                         __func__, kind);
1649                 return 0;
1650         }
1651
1652         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1653         return rc;
1654 }
1655
1656 static inline int may_rename(struct inode *old_dir,
1657                              struct dentry *old_dentry,
1658                              struct inode *new_dir,
1659                              struct dentry *new_dentry)
1660 {
1661         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1662         struct common_audit_data ad;
1663         u32 sid = current_sid();
1664         u32 av;
1665         int old_is_dir, new_is_dir;
1666         int rc;
1667
1668         old_dsec = old_dir->i_security;
1669         old_isec = old_dentry->d_inode->i_security;
1670         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1671         new_dsec = new_dir->i_security;
1672
1673         COMMON_AUDIT_DATA_INIT(&ad, FS);
1674
1675         ad.u.fs.path.dentry = old_dentry;
1676         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1677                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1678         if (rc)
1679                 return rc;
1680         rc = avc_has_perm(sid, old_isec->sid,
1681                           old_isec->sclass, FILE__RENAME, &ad);
1682         if (rc)
1683                 return rc;
1684         if (old_is_dir && new_dir != old_dir) {
1685                 rc = avc_has_perm(sid, old_isec->sid,
1686                                   old_isec->sclass, DIR__REPARENT, &ad);
1687                 if (rc)
1688                         return rc;
1689         }
1690
1691         ad.u.fs.path.dentry = new_dentry;
1692         av = DIR__ADD_NAME | DIR__SEARCH;
1693         if (new_dentry->d_inode)
1694                 av |= DIR__REMOVE_NAME;
1695         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1696         if (rc)
1697                 return rc;
1698         if (new_dentry->d_inode) {
1699                 new_isec = new_dentry->d_inode->i_security;
1700                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1701                 rc = avc_has_perm(sid, new_isec->sid,
1702                                   new_isec->sclass,
1703                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1704                 if (rc)
1705                         return rc;
1706         }
1707
1708         return 0;
1709 }
1710
1711 /* Check whether a task can perform a filesystem operation. */
1712 static int superblock_has_perm(const struct cred *cred,
1713                                struct super_block *sb,
1714                                u32 perms,
1715                                struct common_audit_data *ad)
1716 {
1717         struct superblock_security_struct *sbsec;
1718         u32 sid = cred_sid(cred);
1719
1720         sbsec = sb->s_security;
1721         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1722 }
1723
1724 /* Convert a Linux mode and permission mask to an access vector. */
1725 static inline u32 file_mask_to_av(int mode, int mask)
1726 {
1727         u32 av = 0;
1728
1729         if ((mode & S_IFMT) != S_IFDIR) {
1730                 if (mask & MAY_EXEC)
1731                         av |= FILE__EXECUTE;
1732                 if (mask & MAY_READ)
1733                         av |= FILE__READ;
1734
1735                 if (mask & MAY_APPEND)
1736                         av |= FILE__APPEND;
1737                 else if (mask & MAY_WRITE)
1738                         av |= FILE__WRITE;
1739
1740         } else {
1741                 if (mask & MAY_EXEC)
1742                         av |= DIR__SEARCH;
1743                 if (mask & MAY_WRITE)
1744                         av |= DIR__WRITE;
1745                 if (mask & MAY_READ)
1746                         av |= DIR__READ;
1747         }
1748
1749         return av;
1750 }
1751
1752 /* Convert a Linux file to an access vector. */
1753 static inline u32 file_to_av(struct file *file)
1754 {
1755         u32 av = 0;
1756
1757         if (file->f_mode & FMODE_READ)
1758                 av |= FILE__READ;
1759         if (file->f_mode & FMODE_WRITE) {
1760                 if (file->f_flags & O_APPEND)
1761                         av |= FILE__APPEND;
1762                 else
1763                         av |= FILE__WRITE;
1764         }
1765         if (!av) {
1766                 /*
1767                  * Special file opened with flags 3 for ioctl-only use.
1768                  */
1769                 av = FILE__IOCTL;
1770         }
1771
1772         return av;
1773 }
1774
1775 /*
1776  * Convert a file to an access vector and include the correct open
1777  * open permission.
1778  */
1779 static inline u32 open_file_to_av(struct file *file)
1780 {
1781         u32 av = file_to_av(file);
1782
1783         if (selinux_policycap_openperm) {
1784                 mode_t mode = file->f_path.dentry->d_inode->i_mode;
1785                 /*
1786                  * lnk files and socks do not really have an 'open'
1787                  */
1788                 if (S_ISREG(mode))
1789                         av |= FILE__OPEN;
1790                 else if (S_ISCHR(mode))
1791                         av |= CHR_FILE__OPEN;
1792                 else if (S_ISBLK(mode))
1793                         av |= BLK_FILE__OPEN;
1794                 else if (S_ISFIFO(mode))
1795                         av |= FIFO_FILE__OPEN;
1796                 else if (S_ISDIR(mode))
1797                         av |= DIR__OPEN;
1798                 else if (S_ISSOCK(mode))
1799                         av |= SOCK_FILE__OPEN;
1800                 else
1801                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1802                                 "unknown mode:%o\n", __func__, mode);
1803         }
1804         return av;
1805 }
1806
1807 /* Hook functions begin here. */
1808
1809 static int selinux_ptrace_access_check(struct task_struct *child,
1810                                      unsigned int mode)
1811 {
1812         int rc;
1813
1814         rc = cap_ptrace_access_check(child, mode);
1815         if (rc)
1816                 return rc;
1817
1818         if (mode == PTRACE_MODE_READ) {
1819                 u32 sid = current_sid();
1820                 u32 csid = task_sid(child);
1821                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1822         }
1823
1824         return current_has_perm(child, PROCESS__PTRACE);
1825 }
1826
1827 static int selinux_ptrace_traceme(struct task_struct *parent)
1828 {
1829         int rc;
1830
1831         rc = cap_ptrace_traceme(parent);
1832         if (rc)
1833                 return rc;
1834
1835         return task_has_perm(parent, current, PROCESS__PTRACE);
1836 }
1837
1838 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1839                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1840 {
1841         int error;
1842
1843         error = current_has_perm(target, PROCESS__GETCAP);
1844         if (error)
1845                 return error;
1846
1847         return cap_capget(target, effective, inheritable, permitted);
1848 }
1849
1850 static int selinux_capset(struct cred *new, const struct cred *old,
1851                           const kernel_cap_t *effective,
1852                           const kernel_cap_t *inheritable,
1853                           const kernel_cap_t *permitted)
1854 {
1855         int error;
1856
1857         error = cap_capset(new, old,
1858                                       effective, inheritable, permitted);
1859         if (error)
1860                 return error;
1861
1862         return cred_has_perm(old, new, PROCESS__SETCAP);
1863 }
1864
1865 /*
1866  * (This comment used to live with the selinux_task_setuid hook,
1867  * which was removed).
1868  *
1869  * Since setuid only affects the current process, and since the SELinux
1870  * controls are not based on the Linux identity attributes, SELinux does not
1871  * need to control this operation.  However, SELinux does control the use of
1872  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1873  */
1874
1875 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1876                            int cap, int audit)
1877 {
1878         int rc;
1879
1880         rc = cap_capable(tsk, cred, cap, audit);
1881         if (rc)
1882                 return rc;
1883
1884         return task_has_capability(tsk, cred, cap, audit);
1885 }
1886
1887 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1888 {
1889         int buflen, rc;
1890         char *buffer, *path, *end;
1891
1892         rc = -ENOMEM;
1893         buffer = (char *)__get_free_page(GFP_KERNEL);
1894         if (!buffer)
1895                 goto out;
1896
1897         buflen = PAGE_SIZE;
1898         end = buffer+buflen;
1899         *--end = '\0';
1900         buflen--;
1901         path = end-1;
1902         *path = '/';
1903         while (table) {
1904                 const char *name = table->procname;
1905                 size_t namelen = strlen(name);
1906                 buflen -= namelen + 1;
1907                 if (buflen < 0)
1908                         goto out_free;
1909                 end -= namelen;
1910                 memcpy(end, name, namelen);
1911                 *--end = '/';
1912                 path = end;
1913                 table = table->parent;
1914         }
1915         buflen -= 4;
1916         if (buflen < 0)
1917                 goto out_free;
1918         end -= 4;
1919         memcpy(end, "/sys", 4);
1920         path = end;
1921         rc = security_genfs_sid("proc", path, tclass, sid);
1922 out_free:
1923         free_page((unsigned long)buffer);
1924 out:
1925         return rc;
1926 }
1927
1928 static int selinux_sysctl(ctl_table *table, int op)
1929 {
1930         int error = 0;
1931         u32 av;
1932         u32 tsid, sid;
1933         int rc;
1934
1935         sid = current_sid();
1936
1937         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1938                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1939         if (rc) {
1940                 /* Default to the well-defined sysctl SID. */
1941                 tsid = SECINITSID_SYSCTL;
1942         }
1943
1944         /* The op values are "defined" in sysctl.c, thereby creating
1945          * a bad coupling between this module and sysctl.c */
1946         if (op == 001) {
1947                 error = avc_has_perm(sid, tsid,
1948                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1949         } else {
1950                 av = 0;
1951                 if (op & 004)
1952                         av |= FILE__READ;
1953                 if (op & 002)
1954                         av |= FILE__WRITE;
1955                 if (av)
1956                         error = avc_has_perm(sid, tsid,
1957                                              SECCLASS_FILE, av, NULL);
1958         }
1959
1960         return error;
1961 }
1962
1963 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1964 {
1965         const struct cred *cred = current_cred();
1966         int rc = 0;
1967
1968         if (!sb)
1969                 return 0;
1970
1971         switch (cmds) {
1972         case Q_SYNC:
1973         case Q_QUOTAON:
1974         case Q_QUOTAOFF:
1975         case Q_SETINFO:
1976         case Q_SETQUOTA:
1977                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1978                 break;
1979         case Q_GETFMT:
1980         case Q_GETINFO:
1981         case Q_GETQUOTA:
1982                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1983                 break;
1984         default:
1985                 rc = 0;  /* let the kernel handle invalid cmds */
1986                 break;
1987         }
1988         return rc;
1989 }
1990
1991 static int selinux_quota_on(struct dentry *dentry)
1992 {
1993         const struct cred *cred = current_cred();
1994
1995         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1996 }
1997
1998 static int selinux_syslog(int type, bool from_file)
1999 {
2000         int rc;
2001
2002         rc = cap_syslog(type, from_file);
2003         if (rc)
2004                 return rc;
2005
2006         switch (type) {
2007         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2008         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2009                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2010                 break;
2011         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2012         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2013         /* Set level of messages printed to console */
2014         case SYSLOG_ACTION_CONSOLE_LEVEL:
2015                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2016                 break;
2017         case SYSLOG_ACTION_CLOSE:       /* Close log */
2018         case SYSLOG_ACTION_OPEN:        /* Open log */
2019         case SYSLOG_ACTION_READ:        /* Read from log */
2020         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
2021         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2022         default:
2023                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2024                 break;
2025         }
2026         return rc;
2027 }
2028
2029 /*
2030  * Check that a process has enough memory to allocate a new virtual
2031  * mapping. 0 means there is enough memory for the allocation to
2032  * succeed and -ENOMEM implies there is not.
2033  *
2034  * Do not audit the selinux permission check, as this is applied to all
2035  * processes that allocate mappings.
2036  */
2037 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2038 {
2039         int rc, cap_sys_admin = 0;
2040
2041         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2042                              SECURITY_CAP_NOAUDIT);
2043         if (rc == 0)
2044                 cap_sys_admin = 1;
2045
2046         return __vm_enough_memory(mm, pages, cap_sys_admin);
2047 }
2048
2049 /* binprm security operations */
2050
2051 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2052 {
2053         const struct task_security_struct *old_tsec;
2054         struct task_security_struct *new_tsec;
2055         struct inode_security_struct *isec;
2056         struct common_audit_data ad;
2057         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2058         int rc;
2059
2060         rc = cap_bprm_set_creds(bprm);
2061         if (rc)
2062                 return rc;
2063
2064         /* SELinux context only depends on initial program or script and not
2065          * the script interpreter */
2066         if (bprm->cred_prepared)
2067                 return 0;
2068
2069         old_tsec = current_security();
2070         new_tsec = bprm->cred->security;
2071         isec = inode->i_security;
2072
2073         /* Default to the current task SID. */
2074         new_tsec->sid = old_tsec->sid;
2075         new_tsec->osid = old_tsec->sid;
2076
2077         /* Reset fs, key, and sock SIDs on execve. */
2078         new_tsec->create_sid = 0;
2079         new_tsec->keycreate_sid = 0;
2080         new_tsec->sockcreate_sid = 0;
2081
2082         if (old_tsec->exec_sid) {
2083                 new_tsec->sid = old_tsec->exec_sid;
2084                 /* Reset exec SID on execve. */
2085                 new_tsec->exec_sid = 0;
2086         } else {
2087                 /* Check for a default transition on this program. */
2088                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2089                                              SECCLASS_PROCESS, &new_tsec->sid);
2090                 if (rc)
2091                         return rc;
2092         }
2093
2094         COMMON_AUDIT_DATA_INIT(&ad, FS);
2095         ad.u.fs.path = bprm->file->f_path;
2096
2097         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2098                 new_tsec->sid = old_tsec->sid;
2099
2100         if (new_tsec->sid == old_tsec->sid) {
2101                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2102                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2103                 if (rc)
2104                         return rc;
2105         } else {
2106                 /* Check permissions for the transition. */
2107                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2108                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2109                 if (rc)
2110                         return rc;
2111
2112                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2113                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2114                 if (rc)
2115                         return rc;
2116
2117                 /* Check for shared state */
2118                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2119                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2120                                           SECCLASS_PROCESS, PROCESS__SHARE,
2121                                           NULL);
2122                         if (rc)
2123                                 return -EPERM;
2124                 }
2125
2126                 /* Make sure that anyone attempting to ptrace over a task that
2127                  * changes its SID has the appropriate permit */
2128                 if (bprm->unsafe &
2129                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2130                         struct task_struct *tracer;
2131                         struct task_security_struct *sec;
2132                         u32 ptsid = 0;
2133
2134                         rcu_read_lock();
2135                         tracer = tracehook_tracer_task(current);
2136                         if (likely(tracer != NULL)) {
2137                                 sec = __task_cred(tracer)->security;
2138                                 ptsid = sec->sid;
2139                         }
2140                         rcu_read_unlock();
2141
2142                         if (ptsid != 0) {
2143                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2144                                                   SECCLASS_PROCESS,
2145                                                   PROCESS__PTRACE, NULL);
2146                                 if (rc)
2147                                         return -EPERM;
2148                         }
2149                 }
2150
2151                 /* Clear any possibly unsafe personality bits on exec: */
2152                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2153         }
2154
2155         return 0;
2156 }
2157
2158 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2159 {
2160         const struct cred *cred = current_cred();
2161         const struct task_security_struct *tsec = cred->security;
2162         u32 sid, osid;
2163         int atsecure = 0;
2164
2165         sid = tsec->sid;
2166         osid = tsec->osid;
2167
2168         if (osid != sid) {
2169                 /* Enable secure mode for SIDs transitions unless
2170                    the noatsecure permission is granted between
2171                    the two SIDs, i.e. ahp returns 0. */
2172                 atsecure = avc_has_perm(osid, sid,
2173                                         SECCLASS_PROCESS,
2174                                         PROCESS__NOATSECURE, NULL);
2175         }
2176
2177         return (atsecure || cap_bprm_secureexec(bprm));
2178 }
2179
2180 extern struct vfsmount *selinuxfs_mount;
2181 extern struct dentry *selinux_null;
2182
2183 /* Derived from fs/exec.c:flush_old_files. */
2184 static inline void flush_unauthorized_files(const struct cred *cred,
2185                                             struct files_struct *files)
2186 {
2187         struct common_audit_data ad;
2188         struct file *file, *devnull = NULL;
2189         struct tty_struct *tty;
2190         struct fdtable *fdt;
2191         long j = -1;
2192         int drop_tty = 0;
2193
2194         tty = get_current_tty();
2195         if (tty) {
2196                 file_list_lock();
2197                 if (!list_empty(&tty->tty_files)) {
2198                         struct inode *inode;
2199
2200                         /* Revalidate access to controlling tty.
2201                            Use inode_has_perm on the tty inode directly rather
2202                            than using file_has_perm, as this particular open
2203                            file may belong to another process and we are only
2204                            interested in the inode-based check here. */
2205                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2206                         inode = file->f_path.dentry->d_inode;
2207                         if (inode_has_perm(cred, inode,
2208                                            FILE__READ | FILE__WRITE, NULL)) {
2209                                 drop_tty = 1;
2210                         }
2211                 }
2212                 file_list_unlock();
2213                 tty_kref_put(tty);
2214         }
2215         /* Reset controlling tty. */
2216         if (drop_tty)
2217                 no_tty();
2218
2219         /* Revalidate access to inherited open files. */
2220
2221         COMMON_AUDIT_DATA_INIT(&ad, FS);
2222
2223         spin_lock(&files->file_lock);
2224         for (;;) {
2225                 unsigned long set, i;
2226                 int fd;
2227
2228                 j++;
2229                 i = j * __NFDBITS;
2230                 fdt = files_fdtable(files);
2231                 if (i >= fdt->max_fds)
2232                         break;
2233                 set = fdt->open_fds->fds_bits[j];
2234                 if (!set)
2235                         continue;
2236                 spin_unlock(&files->file_lock);
2237                 for ( ; set ; i++, set >>= 1) {
2238                         if (set & 1) {
2239                                 file = fget(i);
2240                                 if (!file)
2241                                         continue;
2242                                 if (file_has_perm(cred,
2243                                                   file,
2244                                                   file_to_av(file))) {
2245                                         sys_close(i);
2246                                         fd = get_unused_fd();
2247                                         if (fd != i) {
2248                                                 if (fd >= 0)
2249                                                         put_unused_fd(fd);
2250                                                 fput(file);
2251                                                 continue;
2252                                         }
2253                                         if (devnull) {
2254                                                 get_file(devnull);
2255                                         } else {
2256                                                 devnull = dentry_open(
2257                                                         dget(selinux_null),
2258                                                         mntget(selinuxfs_mount),
2259                                                         O_RDWR, cred);
2260                                                 if (IS_ERR(devnull)) {
2261                                                         devnull = NULL;
2262                                                         put_unused_fd(fd);
2263                                                         fput(file);
2264                                                         continue;
2265                                                 }
2266                                         }
2267                                         fd_install(fd, devnull);
2268                                 }
2269                                 fput(file);
2270                         }
2271                 }
2272                 spin_lock(&files->file_lock);
2273
2274         }
2275         spin_unlock(&files->file_lock);
2276 }
2277
2278 /*
2279  * Prepare a process for imminent new credential changes due to exec
2280  */
2281 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2282 {
2283         struct task_security_struct *new_tsec;
2284         struct rlimit *rlim, *initrlim;
2285         int rc, i;
2286
2287         new_tsec = bprm->cred->security;
2288         if (new_tsec->sid == new_tsec->osid)
2289                 return;
2290
2291         /* Close files for which the new task SID is not authorized. */
2292         flush_unauthorized_files(bprm->cred, current->files);
2293
2294         /* Always clear parent death signal on SID transitions. */
2295         current->pdeath_signal = 0;
2296
2297         /* Check whether the new SID can inherit resource limits from the old
2298          * SID.  If not, reset all soft limits to the lower of the current
2299          * task's hard limit and the init task's soft limit.
2300          *
2301          * Note that the setting of hard limits (even to lower them) can be
2302          * controlled by the setrlimit check.  The inclusion of the init task's
2303          * soft limit into the computation is to avoid resetting soft limits
2304          * higher than the default soft limit for cases where the default is
2305          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2306          */
2307         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2308                           PROCESS__RLIMITINH, NULL);
2309         if (rc) {
2310                 for (i = 0; i < RLIM_NLIMITS; i++) {
2311                         rlim = current->signal->rlim + i;
2312                         initrlim = init_task.signal->rlim + i;
2313                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2314                 }
2315                 update_rlimit_cpu(current->signal->rlim[RLIMIT_CPU].rlim_cur);
2316         }
2317 }
2318
2319 /*
2320  * Clean up the process immediately after the installation of new credentials
2321  * due to exec
2322  */
2323 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2324 {
2325         const struct task_security_struct *tsec = current_security();
2326         struct itimerval itimer;
2327         u32 osid, sid;
2328         int rc, i;
2329
2330         osid = tsec->osid;
2331         sid = tsec->sid;
2332
2333         if (sid == osid)
2334                 return;
2335
2336         /* Check whether the new SID can inherit signal state from the old SID.
2337          * If not, clear itimers to avoid subsequent signal generation and
2338          * flush and unblock signals.
2339          *
2340          * This must occur _after_ the task SID has been updated so that any
2341          * kill done after the flush will be checked against the new SID.
2342          */
2343         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2344         if (rc) {
2345                 memset(&itimer, 0, sizeof itimer);
2346                 for (i = 0; i < 3; i++)
2347                         do_setitimer(i, &itimer, NULL);
2348                 spin_lock_irq(&current->sighand->siglock);
2349                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2350                         __flush_signals(current);
2351                         flush_signal_handlers(current, 1);
2352                         sigemptyset(&current->blocked);
2353                 }
2354                 spin_unlock_irq(&current->sighand->siglock);
2355         }
2356
2357         /* Wake up the parent if it is waiting so that it can recheck
2358          * wait permission to the new task SID. */
2359         read_lock(&tasklist_lock);
2360         __wake_up_parent(current, current->real_parent);
2361         read_unlock(&tasklist_lock);
2362 }
2363
2364 /* superblock security operations */
2365
2366 static int selinux_sb_alloc_security(struct super_block *sb)
2367 {
2368         return superblock_alloc_security(sb);
2369 }
2370
2371 static void selinux_sb_free_security(struct super_block *sb)
2372 {
2373         superblock_free_security(sb);
2374 }
2375
2376 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2377 {
2378         if (plen > olen)
2379                 return 0;
2380
2381         return !memcmp(prefix, option, plen);
2382 }
2383
2384 static inline int selinux_option(char *option, int len)
2385 {
2386         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2387                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2388                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2389                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2390                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2391 }
2392
2393 static inline void take_option(char **to, char *from, int *first, int len)
2394 {
2395         if (!*first) {
2396                 **to = ',';
2397                 *to += 1;
2398         } else
2399                 *first = 0;
2400         memcpy(*to, from, len);
2401         *to += len;
2402 }
2403
2404 static inline void take_selinux_option(char **to, char *from, int *first,
2405                                        int len)
2406 {
2407         int current_size = 0;
2408
2409         if (!*first) {
2410                 **to = '|';
2411                 *to += 1;
2412         } else
2413                 *first = 0;
2414
2415         while (current_size < len) {
2416                 if (*from != '"') {
2417                         **to = *from;
2418                         *to += 1;
2419                 }
2420                 from += 1;
2421                 current_size += 1;
2422         }
2423 }
2424
2425 static int selinux_sb_copy_data(char *orig, char *copy)
2426 {
2427         int fnosec, fsec, rc = 0;
2428         char *in_save, *in_curr, *in_end;
2429         char *sec_curr, *nosec_save, *nosec;
2430         int open_quote = 0;
2431
2432         in_curr = orig;
2433         sec_curr = copy;
2434
2435         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2436         if (!nosec) {
2437                 rc = -ENOMEM;
2438                 goto out;
2439         }
2440
2441         nosec_save = nosec;
2442         fnosec = fsec = 1;
2443         in_save = in_end = orig;
2444
2445         do {
2446                 if (*in_end == '"')
2447                         open_quote = !open_quote;
2448                 if ((*in_end == ',' && open_quote == 0) ||
2449                                 *in_end == '\0') {
2450                         int len = in_end - in_curr;
2451
2452                         if (selinux_option(in_curr, len))
2453                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2454                         else
2455                                 take_option(&nosec, in_curr, &fnosec, len);
2456
2457                         in_curr = in_end + 1;
2458                 }
2459         } while (*in_end++);
2460
2461         strcpy(in_save, nosec_save);
2462         free_page((unsigned long)nosec_save);
2463 out:
2464         return rc;
2465 }
2466
2467 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2468 {
2469         const struct cred *cred = current_cred();
2470         struct common_audit_data ad;
2471         int rc;
2472
2473         rc = superblock_doinit(sb, data);
2474         if (rc)
2475                 return rc;
2476
2477         /* Allow all mounts performed by the kernel */
2478         if (flags & MS_KERNMOUNT)
2479                 return 0;
2480
2481         COMMON_AUDIT_DATA_INIT(&ad, FS);
2482         ad.u.fs.path.dentry = sb->s_root;
2483         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2484 }
2485
2486 static int selinux_sb_statfs(struct dentry *dentry)
2487 {
2488         const struct cred *cred = current_cred();
2489         struct common_audit_data ad;
2490
2491         COMMON_AUDIT_DATA_INIT(&ad, FS);
2492         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2493         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2494 }
2495
2496 static int selinux_mount(char *dev_name,
2497                          struct path *path,
2498                          char *type,
2499                          unsigned long flags,
2500                          void *data)
2501 {
2502         const struct cred *cred = current_cred();
2503
2504         if (flags & MS_REMOUNT)
2505                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2506                                            FILESYSTEM__REMOUNT, NULL);
2507         else
2508                 return dentry_has_perm(cred, path->mnt, path->dentry,
2509                                        FILE__MOUNTON);
2510 }
2511
2512 static int selinux_umount(struct vfsmount *mnt, int flags)
2513 {
2514         const struct cred *cred = current_cred();
2515
2516         return superblock_has_perm(cred, mnt->mnt_sb,
2517                                    FILESYSTEM__UNMOUNT, NULL);
2518 }
2519
2520 /* inode security operations */
2521
2522 static int selinux_inode_alloc_security(struct inode *inode)
2523 {
2524         return inode_alloc_security(inode);
2525 }
2526
2527 static void selinux_inode_free_security(struct inode *inode)
2528 {
2529         inode_free_security(inode);
2530 }
2531
2532 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2533                                        char **name, void **value,
2534                                        size_t *len)
2535 {
2536         const struct cred *cred = current_cred();
2537         const struct task_security_struct *tsec = cred->security;
2538         struct inode_security_struct *dsec;
2539         struct superblock_security_struct *sbsec;
2540         u32 sid, newsid, clen;
2541         int rc;
2542         char *namep = NULL, *context;
2543
2544         dsec = dir->i_security;
2545         sbsec = dir->i_sb->s_security;
2546
2547         sid = tsec->sid;
2548         newsid = tsec->create_sid;
2549
2550         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2551                 rc = security_transition_sid(sid, dsec->sid,
2552                                              inode_mode_to_security_class(inode->i_mode),
2553                                              &newsid);
2554                 if (rc) {
2555                         printk(KERN_WARNING "%s:  "
2556                                "security_transition_sid failed, rc=%d (dev=%s "
2557                                "ino=%ld)\n",
2558                                __func__,
2559                                -rc, inode->i_sb->s_id, inode->i_ino);
2560                         return rc;
2561                 }
2562         }
2563
2564         /* Possibly defer initialization to selinux_complete_init. */
2565         if (sbsec->flags & SE_SBINITIALIZED) {
2566                 struct inode_security_struct *isec = inode->i_security;
2567                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2568                 isec->sid = newsid;
2569                 isec->initialized = 1;
2570         }
2571
2572         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2573                 return -EOPNOTSUPP;
2574
2575         if (name) {
2576                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2577                 if (!namep)
2578                         return -ENOMEM;
2579                 *name = namep;
2580         }
2581
2582         if (value && len) {
2583                 rc = security_sid_to_context_force(newsid, &context, &clen);
2584                 if (rc) {
2585                         kfree(namep);
2586                         return rc;
2587                 }
2588                 *value = context;
2589                 *len = clen;
2590         }
2591
2592         return 0;
2593 }
2594
2595 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2596 {
2597         return may_create(dir, dentry, SECCLASS_FILE);
2598 }
2599
2600 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2601 {
2602         return may_link(dir, old_dentry, MAY_LINK);
2603 }
2604
2605 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2606 {
2607         return may_link(dir, dentry, MAY_UNLINK);
2608 }
2609
2610 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2611 {
2612         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2613 }
2614
2615 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2616 {
2617         return may_create(dir, dentry, SECCLASS_DIR);
2618 }
2619
2620 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2621 {
2622         return may_link(dir, dentry, MAY_RMDIR);
2623 }
2624
2625 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2626 {
2627         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2628 }
2629
2630 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2631                                 struct inode *new_inode, struct dentry *new_dentry)
2632 {
2633         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2634 }
2635
2636 static int selinux_inode_readlink(struct dentry *dentry)
2637 {
2638         const struct cred *cred = current_cred();
2639
2640         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2641 }
2642
2643 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2644 {
2645         const struct cred *cred = current_cred();
2646
2647         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2648 }
2649
2650 static int selinux_inode_permission(struct inode *inode, int mask)
2651 {
2652         const struct cred *cred = current_cred();
2653
2654         if (!mask) {
2655                 /* No permission to check.  Existence test. */
2656                 return 0;
2657         }
2658
2659         return inode_has_perm(cred, inode,
2660                               file_mask_to_av(inode->i_mode, mask), NULL);
2661 }
2662
2663 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2664 {
2665         const struct cred *cred = current_cred();
2666         unsigned int ia_valid = iattr->ia_valid;
2667
2668         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2669         if (ia_valid & ATTR_FORCE) {
2670                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2671                               ATTR_FORCE);
2672                 if (!ia_valid)
2673                         return 0;
2674         }
2675
2676         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2677                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2678                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2679
2680         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2681 }
2682
2683 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2684 {
2685         const struct cred *cred = current_cred();
2686
2687         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2688 }
2689
2690 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2691 {
2692         const struct cred *cred = current_cred();
2693
2694         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2695                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2696                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2697                         if (!capable(CAP_SETFCAP))
2698                                 return -EPERM;
2699                 } else if (!capable(CAP_SYS_ADMIN)) {
2700                         /* A different attribute in the security namespace.
2701                            Restrict to administrator. */
2702                         return -EPERM;
2703                 }
2704         }
2705
2706         /* Not an attribute we recognize, so just check the
2707            ordinary setattr permission. */
2708         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2709 }
2710
2711 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2712                                   const void *value, size_t size, int flags)
2713 {
2714         struct inode *inode = dentry->d_inode;
2715         struct inode_security_struct *isec = inode->i_security;
2716         struct superblock_security_struct *sbsec;
2717         struct common_audit_data ad;
2718         u32 newsid, sid = current_sid();
2719         int rc = 0;
2720
2721         if (strcmp(name, XATTR_NAME_SELINUX))
2722                 return selinux_inode_setotherxattr(dentry, name);
2723
2724         sbsec = inode->i_sb->s_security;
2725         if (!(sbsec->flags & SE_SBLABELSUPP))
2726                 return -EOPNOTSUPP;
2727
2728         if (!is_owner_or_cap(inode))
2729                 return -EPERM;
2730
2731         COMMON_AUDIT_DATA_INIT(&ad, FS);
2732         ad.u.fs.path.dentry = dentry;
2733
2734         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2735                           FILE__RELABELFROM, &ad);
2736         if (rc)
2737                 return rc;
2738
2739         rc = security_context_to_sid(value, size, &newsid);
2740         if (rc == -EINVAL) {
2741                 if (!capable(CAP_MAC_ADMIN))
2742                         return rc;
2743                 rc = security_context_to_sid_force(value, size, &newsid);
2744         }
2745         if (rc)
2746                 return rc;
2747
2748         rc = avc_has_perm(sid, newsid, isec->sclass,
2749                           FILE__RELABELTO, &ad);
2750         if (rc)
2751                 return rc;
2752
2753         rc = security_validate_transition(isec->sid, newsid, sid,
2754                                           isec->sclass);
2755         if (rc)
2756                 return rc;
2757
2758         return avc_has_perm(newsid,
2759                             sbsec->sid,
2760                             SECCLASS_FILESYSTEM,
2761                             FILESYSTEM__ASSOCIATE,
2762                             &ad);
2763 }
2764
2765 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2766                                         const void *value, size_t size,
2767                                         int flags)
2768 {
2769         struct inode *inode = dentry->d_inode;
2770         struct inode_security_struct *isec = inode->i_security;
2771         u32 newsid;
2772         int rc;
2773
2774         if (strcmp(name, XATTR_NAME_SELINUX)) {
2775                 /* Not an attribute we recognize, so nothing to do. */
2776                 return;
2777         }
2778
2779         rc = security_context_to_sid_force(value, size, &newsid);
2780         if (rc) {
2781                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2782                        "for (%s, %lu), rc=%d\n",
2783                        inode->i_sb->s_id, inode->i_ino, -rc);
2784                 return;
2785         }
2786
2787         isec->sid = newsid;
2788         return;
2789 }
2790
2791 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2792 {
2793         const struct cred *cred = current_cred();
2794
2795         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2796 }
2797
2798 static int selinux_inode_listxattr(struct dentry *dentry)
2799 {
2800         const struct cred *cred = current_cred();
2801
2802         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2803 }
2804
2805 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2806 {
2807         if (strcmp(name, XATTR_NAME_SELINUX))
2808                 return selinux_inode_setotherxattr(dentry, name);
2809
2810         /* No one is allowed to remove a SELinux security label.
2811            You can change the label, but all data must be labeled. */
2812         return -EACCES;
2813 }
2814
2815 /*
2816  * Copy the inode security context value to the user.
2817  *
2818  * Permission check is handled by selinux_inode_getxattr hook.
2819  */
2820 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2821 {
2822         u32 size;
2823         int error;
2824         char *context = NULL;
2825         struct inode_security_struct *isec = inode->i_security;
2826
2827         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2828                 return -EOPNOTSUPP;
2829
2830         /*
2831          * If the caller has CAP_MAC_ADMIN, then get the raw context
2832          * value even if it is not defined by current policy; otherwise,
2833          * use the in-core value under current policy.
2834          * Use the non-auditing forms of the permission checks since
2835          * getxattr may be called by unprivileged processes commonly
2836          * and lack of permission just means that we fall back to the
2837          * in-core context value, not a denial.
2838          */
2839         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2840                                 SECURITY_CAP_NOAUDIT);
2841         if (!error)
2842                 error = security_sid_to_context_force(isec->sid, &context,
2843                                                       &size);
2844         else
2845                 error = security_sid_to_context(isec->sid, &context, &size);
2846         if (error)
2847                 return error;
2848         error = size;
2849         if (alloc) {
2850                 *buffer = context;
2851                 goto out_nofree;
2852         }
2853         kfree(context);
2854 out_nofree:
2855         return error;
2856 }
2857
2858 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2859                                      const void *value, size_t size, int flags)
2860 {
2861         struct inode_security_struct *isec = inode->i_security;
2862         u32 newsid;
2863         int rc;
2864
2865         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2866                 return -EOPNOTSUPP;
2867
2868         if (!value || !size)
2869                 return -EACCES;
2870
2871         rc = security_context_to_sid((void *)value, size, &newsid);
2872         if (rc)
2873                 return rc;
2874
2875         isec->sid = newsid;
2876         isec->initialized = 1;
2877         return 0;
2878 }
2879
2880 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2881 {
2882         const int len = sizeof(XATTR_NAME_SELINUX);
2883         if (buffer && len <= buffer_size)
2884                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2885         return len;
2886 }
2887
2888 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2889 {
2890         struct inode_security_struct *isec = inode->i_security;
2891         *secid = isec->sid;
2892 }
2893
2894 /* file security operations */
2895
2896 static int selinux_revalidate_file_permission(struct file *file, int mask)
2897 {
2898         const struct cred *cred = current_cred();
2899         struct inode *inode = file->f_path.dentry->d_inode;
2900
2901         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2902         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2903                 mask |= MAY_APPEND;
2904
2905         return file_has_perm(cred, file,
2906                              file_mask_to_av(inode->i_mode, mask));
2907 }
2908
2909 static int selinux_file_permission(struct file *file, int mask)
2910 {
2911         struct inode *inode = file->f_path.dentry->d_inode;
2912         struct file_security_struct *fsec = file->f_security;
2913         struct inode_security_struct *isec = inode->i_security;
2914         u32 sid = current_sid();
2915
2916         if (!mask)
2917                 /* No permission to check.  Existence test. */
2918                 return 0;
2919
2920         if (sid == fsec->sid && fsec->isid == isec->sid &&
2921             fsec->pseqno == avc_policy_seqno())
2922                 /* No change since dentry_open check. */
2923                 return 0;
2924
2925         return selinux_revalidate_file_permission(file, mask);
2926 }
2927
2928 static int selinux_file_alloc_security(struct file *file)
2929 {
2930         return file_alloc_security(file);
2931 }
2932
2933 static void selinux_file_free_security(struct file *file)
2934 {
2935         file_free_security(file);
2936 }
2937
2938 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2939                               unsigned long arg)
2940 {
2941         const struct cred *cred = current_cred();
2942         u32 av = 0;
2943
2944         if (_IOC_DIR(cmd) & _IOC_WRITE)
2945                 av |= FILE__WRITE;
2946         if (_IOC_DIR(cmd) & _IOC_READ)
2947                 av |= FILE__READ;
2948         if (!av)
2949                 av = FILE__IOCTL;
2950
2951         return file_has_perm(cred, file, av);
2952 }
2953
2954 static int default_noexec;
2955
2956 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2957 {
2958         const struct cred *cred = current_cred();
2959         int rc = 0;
2960
2961         if (default_noexec &&
2962             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2963                 /*
2964                  * We are making executable an anonymous mapping or a
2965                  * private file mapping that will also be writable.
2966                  * This has an additional check.
2967                  */
2968                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
2969                 if (rc)
2970                         goto error;
2971         }
2972
2973         if (file) {
2974                 /* read access is always possible with a mapping */
2975                 u32 av = FILE__READ;
2976
2977                 /* write access only matters if the mapping is shared */
2978                 if (shared && (prot & PROT_WRITE))
2979                         av |= FILE__WRITE;
2980
2981                 if (prot & PROT_EXEC)
2982                         av |= FILE__EXECUTE;
2983
2984                 return file_has_perm(cred, file, av);
2985         }
2986
2987 error:
2988         return rc;
2989 }
2990
2991 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2992                              unsigned long prot, unsigned long flags,
2993                              unsigned long addr, unsigned long addr_only)
2994 {
2995         int rc = 0;
2996         u32 sid = current_sid();
2997
2998         /*
2999          * notice that we are intentionally putting the SELinux check before
3000          * the secondary cap_file_mmap check.  This is such a likely attempt
3001          * at bad behaviour/exploit that we always want to get the AVC, even
3002          * if DAC would have also denied the operation.
3003          */
3004         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3005                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3006                                   MEMPROTECT__MMAP_ZERO, NULL);
3007                 if (rc)
3008                         return rc;
3009         }
3010
3011         /* do DAC check on address space usage */
3012         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3013         if (rc || addr_only)
3014                 return rc;
3015
3016         if (selinux_checkreqprot)
3017                 prot = reqprot;
3018
3019         return file_map_prot_check(file, prot,
3020                                    (flags & MAP_TYPE) == MAP_SHARED);
3021 }
3022
3023 static int selinux_file_mprotect(struct vm_area_struct *vma,
3024                                  unsigned long reqprot,
3025                                  unsigned long prot)
3026 {
3027         const struct cred *cred = current_cred();
3028
3029         if (selinux_checkreqprot)
3030                 prot = reqprot;
3031
3032         if (default_noexec &&
3033             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3034                 int rc = 0;
3035                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3036                     vma->vm_end <= vma->vm_mm->brk) {
3037                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3038                 } else if (!vma->vm_file &&
3039                            vma->vm_start <= vma->vm_mm->start_stack &&
3040                            vma->vm_end >= vma->vm_mm->start_stack) {
3041                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3042                 } else if (vma->vm_file && vma->anon_vma) {
3043                         /*
3044                          * We are making executable a file mapping that has
3045                          * had some COW done. Since pages might have been
3046                          * written, check ability to execute the possibly
3047                          * modified content.  This typically should only
3048                          * occur for text relocations.
3049                          */
3050                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3051                 }
3052                 if (rc)
3053                         return rc;
3054         }
3055
3056         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3057 }
3058
3059 static int selinux_file_lock(struct file *file, unsigned int cmd)
3060 {
3061         const struct cred *cred = current_cred();
3062
3063         return file_has_perm(cred, file, FILE__LOCK);
3064 }
3065
3066 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3067                               unsigned long arg)
3068 {
3069         const struct cred *cred = current_cred();
3070         int err = 0;
3071
3072         switch (cmd) {
3073         case F_SETFL:
3074                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3075                         err = -EINVAL;
3076                         break;
3077                 }
3078
3079                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3080                         err = file_has_perm(cred, file, FILE__WRITE);
3081                         break;
3082                 }
3083                 /* fall through */
3084         case F_SETOWN:
3085         case F_SETSIG:
3086         case F_GETFL:
3087         case F_GETOWN:
3088         case F_GETSIG:
3089                 /* Just check FD__USE permission */
3090                 err = file_has_perm(cred, file, 0);
3091                 break;
3092         case F_GETLK:
3093         case F_SETLK:
3094         case F_SETLKW:
3095 #if BITS_PER_LONG == 32
3096         case F_GETLK64:
3097         case F_SETLK64:
3098         case F_SETLKW64:
3099 #endif
3100                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3101                         err = -EINVAL;
3102                         break;
3103                 }
3104                 err = file_has_perm(cred, file, FILE__LOCK);
3105                 break;
3106         }
3107
3108         return err;
3109 }
3110
3111 static int selinux_file_set_fowner(struct file *file)
3112 {
3113         struct file_security_struct *fsec;
3114
3115         fsec = file->f_security;
3116         fsec->fown_sid = current_sid();
3117
3118         return 0;
3119 }
3120
3121 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3122                                        struct fown_struct *fown, int signum)
3123 {
3124         struct file *file;
3125         u32 sid = task_sid(tsk);
3126         u32 perm;
3127         struct file_security_struct *fsec;
3128
3129         /* struct fown_struct is never outside the context of a struct file */
3130         file = container_of(fown, struct file, f_owner);
3131
3132         fsec = file->f_security;
3133
3134         if (!signum)
3135                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3136         else
3137                 perm = signal_to_av(signum);
3138
3139         return avc_has_perm(fsec->fown_sid, sid,
3140                             SECCLASS_PROCESS, perm, NULL);
3141 }
3142
3143 static int selinux_file_receive(struct file *file)
3144 {
3145         const struct cred *cred = current_cred();
3146
3147         return file_has_perm(cred, file, file_to_av(file));
3148 }
3149
3150 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3151 {
3152         struct file_security_struct *fsec;
3153         struct inode *inode;
3154         struct inode_security_struct *isec;
3155
3156         inode = file->f_path.dentry->d_inode;
3157         fsec = file->f_security;
3158         isec = inode->i_security;
3159         /*
3160          * Save inode label and policy sequence number
3161          * at open-time so that selinux_file_permission
3162          * can determine whether revalidation is necessary.
3163          * Task label is already saved in the file security
3164          * struct as its SID.
3165          */
3166         fsec->isid = isec->sid;
3167         fsec->pseqno = avc_policy_seqno();
3168         /*
3169          * Since the inode label or policy seqno may have changed
3170          * between the selinux_inode_permission check and the saving
3171          * of state above, recheck that access is still permitted.
3172          * Otherwise, access might never be revalidated against the
3173          * new inode label or new policy.
3174          * This check is not redundant - do not remove.
3175          */
3176         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3177 }
3178
3179 /* task security operations */
3180
3181 static int selinux_task_create(unsigned long clone_flags)
3182 {
3183         return current_has_perm(current, PROCESS__FORK);
3184 }
3185
3186 /*
3187  * allocate the SELinux part of blank credentials
3188  */
3189 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3190 {
3191         struct task_security_struct *tsec;
3192
3193         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3194         if (!tsec)
3195                 return -ENOMEM;
3196
3197         cred->security = tsec;
3198         return 0;
3199 }
3200
3201 /*
3202  * detach and free the LSM part of a set of credentials
3203  */
3204 static void selinux_cred_free(struct cred *cred)
3205 {
3206         struct task_security_struct *tsec = cred->security;
3207
3208         BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3209         cred->security = (void *) 0x7UL;
3210         kfree(tsec);
3211 }
3212
3213 /*
3214  * prepare a new set of credentials for modification
3215  */
3216 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3217                                 gfp_t gfp)
3218 {
3219         const struct task_security_struct *old_tsec;
3220         struct task_security_struct *tsec;
3221
3222         old_tsec = old->security;
3223
3224         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3225         if (!tsec)
3226                 return -ENOMEM;
3227
3228         new->security = tsec;
3229         return 0;
3230 }
3231
3232 /*
3233  * transfer the SELinux data to a blank set of creds
3234  */
3235 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3236 {
3237         const struct task_security_struct *old_tsec = old->security;
3238         struct task_security_struct *tsec = new->security;
3239
3240         *tsec = *old_tsec;
3241 }
3242
3243 /*
3244  * set the security data for a kernel service
3245  * - all the creation contexts are set to unlabelled
3246  */
3247 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3248 {
3249         struct task_security_struct *tsec = new->security;
3250         u32 sid = current_sid();
3251         int ret;
3252
3253         ret = avc_has_perm(sid, secid,
3254                            SECCLASS_KERNEL_SERVICE,
3255                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3256                            NULL);
3257         if (ret == 0) {
3258                 tsec->sid = secid;
3259                 tsec->create_sid = 0;
3260                 tsec->keycreate_sid = 0;
3261                 tsec->sockcreate_sid = 0;
3262         }
3263         return ret;
3264 }
3265
3266 /*
3267  * set the file creation context in a security record to the same as the
3268  * objective context of the specified inode
3269  */
3270 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3271 {
3272         struct inode_security_struct *isec = inode->i_security;
3273         struct task_security_struct *tsec = new->security;
3274         u32 sid = current_sid();
3275         int ret;
3276
3277         ret = avc_has_perm(sid, isec->sid,
3278                            SECCLASS_KERNEL_SERVICE,
3279                            KERNEL_SERVICE__CREATE_FILES_AS,
3280                            NULL);
3281
3282         if (ret == 0)
3283                 tsec->create_sid = isec->sid;
3284         return ret;
3285 }
3286
3287 static int selinux_kernel_module_request(char *kmod_name)
3288 {
3289         u32 sid;
3290         struct common_audit_data ad;
3291
3292         sid = task_sid(current);
3293
3294         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3295         ad.u.kmod_name = kmod_name;
3296
3297         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3298                             SYSTEM__MODULE_REQUEST, &ad);
3299 }
3300
3301 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3302 {
3303         return current_has_perm(p, PROCESS__SETPGID);
3304 }
3305
3306 static int selinux_task_getpgid(struct task_struct *p)
3307 {
3308         return current_has_perm(p, PROCESS__GETPGID);
3309 }
3310
3311 static int selinux_task_getsid(struct task_struct *p)
3312 {
3313         return current_has_perm(p, PROCESS__GETSESSION);
3314 }
3315
3316 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3317 {
3318         *secid = task_sid(p);
3319 }
3320
3321 static int selinux_task_setnice(struct task_struct *p, int nice)
3322 {
3323         int rc;
3324
3325         rc = cap_task_setnice(p, nice);
3326         if (rc)
3327                 return rc;
3328
3329         return current_has_perm(p, PROCESS__SETSCHED);
3330 }
3331
3332 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3333 {
3334         int rc;
3335
3336         rc = cap_task_setioprio(p, ioprio);
3337         if (rc)
3338                 return rc;
3339
3340         return current_has_perm(p, PROCESS__SETSCHED);
3341 }
3342
3343 static int selinux_task_getioprio(struct task_struct *p)
3344 {
3345         return current_has_perm(p, PROCESS__GETSCHED);
3346 }
3347
3348 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3349 {
3350         struct rlimit *old_rlim = current->signal->rlim + resource;
3351
3352         /* Control the ability to change the hard limit (whether
3353            lowering or raising it), so that the hard limit can
3354            later be used as a safe reset point for the soft limit
3355            upon context transitions.  See selinux_bprm_committing_creds. */
3356         if (old_rlim->rlim_max != new_rlim->rlim_max)
3357                 return current_has_perm(current, PROCESS__SETRLIMIT);
3358
3359         return 0;
3360 }
3361
3362 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3363 {
3364         int rc;
3365
3366         rc = cap_task_setscheduler(p, policy, lp);
3367         if (rc)
3368                 return rc;
3369
3370         return current_has_perm(p, PROCESS__SETSCHED);
3371 }
3372
3373 static int selinux_task_getscheduler(struct task_struct *p)
3374 {
3375         return current_has_perm(p, PROCESS__GETSCHED);
3376 }
3377
3378 static int selinux_task_movememory(struct task_struct *p)
3379 {
3380         return current_has_perm(p, PROCESS__SETSCHED);
3381 }
3382
3383 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3384                                 int sig, u32 secid)
3385 {
3386         u32 perm;
3387         int rc;
3388
3389         if (!sig)
3390                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3391         else
3392                 perm = signal_to_av(sig);
3393         if (secid)
3394                 rc = avc_has_perm(secid, task_sid(p),
3395                                   SECCLASS_PROCESS, perm, NULL);
3396         else
3397                 rc = current_has_perm(p, perm);
3398         return rc;
3399 }
3400
3401 static int selinux_task_wait(struct task_struct *p)
3402 {
3403         return task_has_perm(p, current, PROCESS__SIGCHLD);
3404 }
3405
3406 static void selinux_task_to_inode(struct task_struct *p,
3407                                   struct inode *inode)
3408 {
3409         struct inode_security_struct *isec = inode->i_security;
3410         u32 sid = task_sid(p);
3411
3412         isec->sid = sid;
3413         isec->initialized = 1;
3414 }
3415
3416 /* Returns error only if unable to parse addresses */
3417 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3418                         struct common_audit_data *ad, u8 *proto)
3419 {
3420         int offset, ihlen, ret = -EINVAL;
3421         struct iphdr _iph, *ih;
3422
3423         offset = skb_network_offset(skb);
3424         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3425         if (ih == NULL)
3426                 goto out;
3427
3428         ihlen = ih->ihl * 4;
3429         if (ihlen < sizeof(_iph))
3430                 goto out;
3431
3432         ad->u.net.v4info.saddr = ih->saddr;
3433         ad->u.net.v4info.daddr = ih->daddr;
3434         ret = 0;
3435
3436         if (proto)
3437                 *proto = ih->protocol;
3438
3439         switch (ih->protocol) {
3440         case IPPROTO_TCP: {
3441                 struct tcphdr _tcph, *th;
3442
3443                 if (ntohs(ih->frag_off) & IP_OFFSET)
3444                         break;
3445
3446                 offset += ihlen;
3447                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3448                 if (th == NULL)
3449                         break;
3450
3451                 ad->u.net.sport = th->source;
3452                 ad->u.net.dport = th->dest;
3453                 break;
3454         }
3455
3456         case IPPROTO_UDP: {
3457                 struct udphdr _udph, *uh;
3458
3459                 if (ntohs(ih->frag_off) & IP_OFFSET)
3460                         break;
3461
3462                 offset += ihlen;
3463                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3464                 if (uh == NULL)
3465                         break;
3466
3467                 ad->u.net.sport = uh->source;
3468                 ad->u.net.dport = uh->dest;
3469                 break;
3470         }
3471
3472         case IPPROTO_DCCP: {
3473                 struct dccp_hdr _dccph, *dh;
3474
3475                 if (ntohs(ih->frag_off) & IP_OFFSET)
3476                         break;
3477
3478                 offset += ihlen;
3479                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3480                 if (dh == NULL)
3481                         break;
3482
3483                 ad->u.net.sport = dh->dccph_sport;
3484                 ad->u.net.dport = dh->dccph_dport;
3485                 break;
3486         }
3487
3488         default:
3489                 break;
3490         }
3491 out:
3492         return ret;
3493 }
3494
3495 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3496
3497 /* Returns error only if unable to parse addresses */
3498 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3499                         struct common_audit_data *ad, u8 *proto)
3500 {
3501         u8 nexthdr;
3502         int ret = -EINVAL, offset;
3503         struct ipv6hdr _ipv6h, *ip6;
3504
3505         offset = skb_network_offset(skb);
3506         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3507         if (ip6 == NULL)
3508                 goto out;
3509
3510         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3511         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3512         ret = 0;
3513
3514         nexthdr = ip6->nexthdr;
3515         offset += sizeof(_ipv6h);
3516         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3517         if (offset < 0)
3518                 goto out;
3519
3520         if (proto)
3521                 *proto = nexthdr;
3522
3523         switch (nexthdr) {
3524         case IPPROTO_TCP: {
3525                 struct tcphdr _tcph, *th;
3526
3527                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3528                 if (th == NULL)
3529                         break;
3530
3531                 ad->u.net.sport = th->source;
3532                 ad->u.net.dport = th->dest;
3533                 break;
3534         }
3535
3536         case IPPROTO_UDP: {
3537                 struct udphdr _udph, *uh;
3538
3539                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3540                 if (uh == NULL)
3541                         break;
3542
3543                 ad->u.net.sport = uh->source;
3544                 ad->u.net.dport = uh->dest;
3545                 break;
3546         }
3547
3548         case IPPROTO_DCCP: {
3549                 struct dccp_hdr _dccph, *dh;
3550
3551                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3552                 if (dh == NULL)
3553                         break;
3554
3555                 ad->u.net.sport = dh->dccph_sport;
3556                 ad->u.net.dport = dh->dccph_dport;
3557                 break;
3558         }
3559
3560         /* includes fragments */
3561         default:
3562                 break;
3563         }
3564 out:
3565         return ret;
3566 }
3567
3568 #endif /* IPV6 */
3569
3570 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3571                              char **_addrp, int src, u8 *proto)
3572 {
3573         char *addrp;
3574         int ret;
3575
3576         switch (ad->u.net.family) {
3577         case PF_INET:
3578                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3579                 if (ret)
3580                         goto parse_error;
3581                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3582                                        &ad->u.net.v4info.daddr);
3583                 goto okay;
3584
3585 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3586         case PF_INET6:
3587                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3588                 if (ret)
3589                         goto parse_error;
3590                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3591                                        &ad->u.net.v6info.daddr);
3592                 goto okay;
3593 #endif  /* IPV6 */
3594         default:
3595                 addrp = NULL;
3596                 goto okay;
3597         }
3598
3599 parse_error:
3600         printk(KERN_WARNING
3601                "SELinux: failure in selinux_parse_skb(),"
3602                " unable to parse packet\n");
3603         return ret;
3604
3605 okay:
3606         if (_addrp)
3607                 *_addrp = addrp;
3608         return 0;
3609 }
3610
3611 /**
3612  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3613  * @skb: the packet
3614  * @family: protocol family
3615  * @sid: the packet's peer label SID
3616  *
3617  * Description:
3618  * Check the various different forms of network peer labeling and determine
3619  * the peer label/SID for the packet; most of the magic actually occurs in
3620  * the security server function security_net_peersid_cmp().  The function
3621  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3622  * or -EACCES if @sid is invalid due to inconsistencies with the different
3623  * peer labels.
3624  *
3625  */
3626 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3627 {
3628         int err;
3629         u32 xfrm_sid;
3630         u32 nlbl_sid;
3631         u32 nlbl_type;
3632
3633         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3634         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3635
3636         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3637         if (unlikely(err)) {
3638                 printk(KERN_WARNING
3639                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3640                        " unable to determine packet's peer label\n");
3641                 return -EACCES;
3642         }
3643
3644         return 0;
3645 }
3646
3647 /* socket security operations */
3648
3649 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3650 {
3651         return tsec->sockcreate_sid ? : tsec->sid;
3652 }
3653
3654 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3655 {
3656         struct sk_security_struct *sksec = sk->sk_security;
3657         struct common_audit_data ad;
3658         u32 tsid = task_sid(task);
3659
3660         if (sksec->sid == SECINITSID_KERNEL)
3661                 return 0;
3662
3663         COMMON_AUDIT_DATA_INIT(&ad, NET);
3664         ad.u.net.sk = sk;
3665
3666         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3667 }
3668
3669 static int selinux_socket_create(int family, int type,
3670                                  int protocol, int kern)
3671 {
3672         const struct cred *cred = current_cred();
3673         const struct task_security_struct *tsec = cred->security;
3674         u32 newsid;
3675         u16 secclass;
3676
3677         if (kern)
3678                 return 0;
3679
3680         newsid = socket_sockcreate_sid(tsec);
3681         secclass = socket_type_to_security_class(family, type, protocol);
3682         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3683 }
3684
3685 static int selinux_socket_post_create(struct socket *sock, int family,
3686                                       int type, int protocol, int kern)
3687 {
3688         const struct cred *cred = current_cred();
3689         const struct task_security_struct *tsec = cred->security;
3690         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3691         struct sk_security_struct *sksec;
3692         int err = 0;
3693
3694         if (kern)
3695                 isec->sid = SECINITSID_KERNEL;
3696         else
3697                 isec->sid = socket_sockcreate_sid(tsec);
3698
3699         isec->sclass = socket_type_to_security_class(family, type, protocol);
3700         isec->initialized = 1;
3701
3702         if (sock->sk) {
3703                 sksec = sock->sk->sk_security;
3704                 sksec->sid = isec->sid;
3705                 sksec->sclass = isec->sclass;
3706                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3707         }
3708
3709         return err;
3710 }
3711
3712 /* Range of port numbers used to automatically bind.
3713    Need to determine whether we should perform a name_bind
3714    permission check between the socket and the port number. */
3715
3716 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3717 {
3718         struct sock *sk = sock->sk;
3719         u16 family;
3720         int err;
3721
3722         err = sock_has_perm(current, sk, SOCKET__BIND);
3723         if (err)
3724                 goto out;
3725
3726         /*
3727          * If PF_INET or PF_INET6, check name_bind permission for the port.
3728          * Multiple address binding for SCTP is not supported yet: we just
3729          * check the first address now.
3730          */
3731         family = sk->sk_family;
3732         if (family == PF_INET || family == PF_INET6) {
3733                 char *addrp;
3734                 struct sk_security_struct *sksec = sk->sk_security;
3735                 struct common_audit_data ad;
3736                 struct sockaddr_in *addr4 = NULL;
3737                 struct sockaddr_in6 *addr6 = NULL;
3738                 unsigned short snum;
3739                 u32 sid, node_perm;
3740
3741                 if (family == PF_INET) {
3742                         addr4 = (struct sockaddr_in *)address;
3743                         snum = ntohs(addr4->sin_port);
3744                         addrp = (char *)&addr4->sin_addr.s_addr;
3745                 } else {
3746                         addr6 = (struct sockaddr_in6 *)address;
3747                         snum = ntohs(addr6->sin6_port);
3748                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3749                 }
3750
3751                 if (snum) {
3752                         int low, high;
3753
3754                         inet_get_local_port_range(&low, &high);
3755
3756                         if (snum < max(PROT_SOCK, low) || snum > high) {
3757                                 err = sel_netport_sid(sk->sk_protocol,
3758                                                       snum, &sid);
3759                                 if (err)
3760                                         goto out;
3761                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3762                                 ad.u.net.sport = htons(snum);
3763                                 ad.u.net.family = family;
3764                                 err = avc_has_perm(sksec->sid, sid,
3765                                                    sksec->sclass,
3766                                                    SOCKET__NAME_BIND, &ad);
3767                                 if (err)
3768                                         goto out;
3769                         }
3770                 }
3771
3772                 switch (sksec->sclass) {
3773                 case SECCLASS_TCP_SOCKET:
3774                         node_perm = TCP_SOCKET__NODE_BIND;
3775                         break;
3776
3777                 case SECCLASS_UDP_SOCKET:
3778                         node_perm = UDP_SOCKET__NODE_BIND;
3779                         break;
3780
3781                 case SECCLASS_DCCP_SOCKET:
3782                         node_perm = DCCP_SOCKET__NODE_BIND;
3783                         break;
3784
3785                 default:
3786                         node_perm = RAWIP_SOCKET__NODE_BIND;
3787                         break;
3788                 }
3789
3790                 err = sel_netnode_sid(addrp, family, &sid);
3791                 if (err)
3792                         goto out;
3793
3794                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3795                 ad.u.net.sport = htons(snum);
3796                 ad.u.net.family = family;
3797
3798                 if (family == PF_INET)
3799                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3800                 else
3801                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3802
3803                 err = avc_has_perm(sksec->sid, sid,
3804                                    sksec->sclass, node_perm, &ad);
3805                 if (err)
3806                         goto out;
3807         }
3808 out:
3809         return err;
3810 }
3811
3812 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3813 {
3814         struct sock *sk = sock->sk;
3815         struct sk_security_struct *sksec = sk->sk_security;
3816         int err;
3817
3818         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3819         if (err)
3820                 return err;
3821
3822         /*
3823          * If a TCP or DCCP socket, check name_connect permission for the port.
3824          */
3825         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3826             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3827                 struct common_audit_data ad;
3828                 struct sockaddr_in *addr4 = NULL;
3829                 struct sockaddr_in6 *addr6 = NULL;
3830                 unsigned short snum;
3831                 u32 sid, perm;
3832
3833                 if (sk->sk_family == PF_INET) {
3834                         addr4 = (struct sockaddr_in *)address;
3835                         if (addrlen < sizeof(struct sockaddr_in))
3836                                 return -EINVAL;
3837                         snum = ntohs(addr4->sin_port);
3838                 } else {
3839                         addr6 = (struct sockaddr_in6 *)address;
3840                         if (addrlen < SIN6_LEN_RFC2133)
3841                                 return -EINVAL;
3842                         snum = ntohs(addr6->sin6_port);
3843                 }
3844
3845                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3846                 if (err)
3847                         goto out;
3848
3849                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3850                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3851
3852                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3853                 ad.u.net.dport = htons(snum);
3854                 ad.u.net.family = sk->sk_family;
3855                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3856                 if (err)
3857                         goto out;
3858         }
3859
3860         err = selinux_netlbl_socket_connect(sk, address);
3861
3862 out:
3863         return err;
3864 }
3865
3866 static int selinux_socket_listen(struct socket *sock, int backlog)
3867 {
3868         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3869 }
3870
3871 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3872 {
3873         int err;
3874         struct inode_security_struct *isec;
3875         struct inode_security_struct *newisec;
3876
3877         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3878         if (err)
3879                 return err;
3880
3881         newisec = SOCK_INODE(newsock)->i_security;
3882
3883         isec = SOCK_INODE(sock)->i_security;
3884         newisec->sclass = isec->sclass;
3885         newisec->sid = isec->sid;
3886         newisec->initialized = 1;
3887
3888         return 0;
3889 }
3890
3891 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3892                                   int size)
3893 {
3894         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3895 }
3896
3897 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3898                                   int size, int flags)
3899 {
3900         return sock_has_perm(current, sock->sk, SOCKET__READ);
3901 }
3902
3903 static int selinux_socket_getsockname(struct socket *sock)
3904 {
3905         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3906 }
3907
3908 static int selinux_socket_getpeername(struct socket *sock)
3909 {
3910         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3911 }
3912
3913 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3914 {
3915         int err;
3916
3917         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3918         if (err)
3919                 return err;
3920
3921         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3922 }
3923
3924 static int selinux_socket_getsockopt(struct socket *sock, int level,
3925                                      int optname)
3926 {
3927         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3928 }
3929
3930 static int selinux_socket_shutdown(struct socket *sock, int how)
3931 {
3932         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3933 }
3934
3935 static int selinux_socket_unix_stream_connect(struct socket *sock,
3936                                               struct socket *other,
3937                                               struct sock *newsk)
3938 {
3939         struct sk_security_struct *sksec_sock = sock->sk->sk_security;
3940         struct sk_security_struct *sksec_other = other->sk->sk_security;
3941         struct sk_security_struct *sksec_new = newsk->sk_security;
3942         struct common_audit_data ad;
3943         int err;
3944
3945         COMMON_AUDIT_DATA_INIT(&ad, NET);
3946         ad.u.net.sk = other->sk;
3947
3948         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3949                            sksec_other->sclass,
3950                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3951         if (err)
3952                 return err;
3953
3954         /* server child socket */
3955         sksec_new->peer_sid = sksec_sock->sid;
3956         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3957                                     &sksec_new->sid);
3958         if (err)
3959                 return err;
3960
3961         /* connecting socket */
3962         sksec_sock->peer_sid = sksec_new->sid;
3963
3964         return 0;
3965 }
3966
3967 static int selinux_socket_unix_may_send(struct socket *sock,
3968                                         struct socket *other)
3969 {
3970         struct sk_security_struct *ssec = sock->sk->sk_security;
3971         struct sk_security_struct *osec = other->sk->sk_security;
3972         struct common_audit_data ad;
3973
3974         COMMON_AUDIT_DATA_INIT(&ad, NET);
3975         ad.u.net.sk = other->sk;
3976
3977         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3978                             &ad);
3979 }
3980
3981 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3982                                     u32 peer_sid,
3983                                     struct common_audit_data *ad)
3984 {
3985         int err;
3986         u32 if_sid;
3987         u32 node_sid;
3988
3989         err = sel_netif_sid(ifindex, &if_sid);
3990         if (err)
3991                 return err;
3992         err = avc_has_perm(peer_sid, if_sid,
3993                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3994         if (err)
3995                 return err;
3996
3997         err = sel_netnode_sid(addrp, family, &node_sid);
3998         if (err)
3999                 return err;
4000         return avc_has_perm(peer_sid, node_sid,
4001                             SECCLASS_NODE, NODE__RECVFROM, ad);
4002 }
4003
4004 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4005                                        u16 family)
4006 {
4007         int err = 0;
4008         struct sk_security_struct *sksec = sk->sk_security;
4009         u32 peer_sid;
4010         u32 sk_sid = sksec->sid;
4011         struct common_audit_data ad;
4012         char *addrp;
4013
4014         COMMON_AUDIT_DATA_INIT(&ad, NET);
4015         ad.u.net.netif = skb->skb_iif;
4016         ad.u.net.family = family;
4017         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4018         if (err)
4019                 return err;
4020
4021         if (selinux_secmark_enabled()) {
4022                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4023                                    PACKET__RECV, &ad);
4024                 if (err)
4025                         return err;
4026         }
4027
4028         if (selinux_policycap_netpeer) {
4029                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4030                 if (err)
4031                         return err;
4032                 err = avc_has_perm(sk_sid, peer_sid,
4033                                    SECCLASS_PEER, PEER__RECV, &ad);
4034                 if (err)
4035                         selinux_netlbl_err(skb, err, 0);
4036         } else {
4037                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4038                 if (err)
4039                         return err;
4040                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4041         }
4042
4043         return err;
4044 }
4045
4046 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4047 {
4048         int err;
4049         struct sk_security_struct *sksec = sk->sk_security;
4050         u16 family = sk->sk_family;
4051         u32 sk_sid = sksec->sid;
4052         struct common_audit_data ad;
4053         char *addrp;
4054         u8 secmark_active;
4055         u8 peerlbl_active;
4056
4057         if (family != PF_INET && family != PF_INET6)
4058                 return 0;
4059
4060         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4061         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4062                 family = PF_INET;
4063
4064         /* If any sort of compatibility mode is enabled then handoff processing
4065          * to the selinux_sock_rcv_skb_compat() function to deal with the
4066          * special handling.  We do this in an attempt to keep this function
4067          * as fast and as clean as possible. */
4068         if (!selinux_policycap_netpeer)
4069                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4070
4071         secmark_active = selinux_secmark_enabled();
4072         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4073         if (!secmark_active && !peerlbl_active)
4074                 return 0;
4075
4076         COMMON_AUDIT_DATA_INIT(&ad, NET);
4077         ad.u.net.netif = skb->skb_iif;
4078         ad.u.net.family = family;
4079         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4080         if (err)
4081                 return err;
4082
4083         if (peerlbl_active) {
4084                 u32 peer_sid;
4085
4086                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4087                 if (err)
4088                         return err;
4089                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4090                                                peer_sid, &ad);
4091                 if (err) {
4092                         selinux_netlbl_err(skb, err, 0);
4093                         return err;
4094                 }
4095                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4096                                    PEER__RECV, &ad);
4097                 if (err)
4098                         selinux_netlbl_err(skb, err, 0);
4099         }
4100
4101         if (secmark_active) {
4102                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4103                                    PACKET__RECV, &ad);
4104                 if (err)
4105                         return err;
4106         }
4107
4108         return err;
4109 }
4110
4111 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4112                                             int __user *optlen, unsigned len)
4113 {
4114         int err = 0;
4115         char *scontext;
4116         u32 scontext_len;
4117         struct sk_security_struct *sksec = sock->sk->sk_security;
4118         u32 peer_sid = SECSID_NULL;
4119
4120         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4121             sksec->sclass == SECCLASS_TCP_SOCKET)
4122                 peer_sid = sksec->peer_sid;
4123         if (peer_sid == SECSID_NULL)
4124                 return -ENOPROTOOPT;
4125
4126         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4127         if (err)
4128                 return err;
4129
4130         if (scontext_len > len) {
4131                 err = -ERANGE;
4132                 goto out_len;
4133         }
4134
4135         if (copy_to_user(optval, scontext, scontext_len))
4136                 err = -EFAULT;
4137
4138 out_len:
4139         if (put_user(scontext_len, optlen))
4140                 err = -EFAULT;
4141         kfree(scontext);
4142         return err;
4143 }
4144
4145 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4146 {
4147         u32 peer_secid = SECSID_NULL;
4148         u16 family;
4149
4150         if (skb && skb->protocol == htons(ETH_P_IP))
4151                 family = PF_INET;
4152         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4153                 family = PF_INET6;
4154         else if (sock)
4155                 family = sock->sk->sk_family;
4156         else
4157                 goto out;
4158
4159         if (sock && family == PF_UNIX)
4160                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4161         else if (skb)
4162                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4163
4164 out:
4165         *secid = peer_secid;
4166         if (peer_secid == SECSID_NULL)
4167                 return -EINVAL;
4168         return 0;
4169 }
4170
4171 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4172 {
4173         struct sk_security_struct *sksec;
4174
4175         sksec = kzalloc(sizeof(*sksec), priority);
4176         if (!sksec)
4177                 return -ENOMEM;
4178
4179         sksec->peer_sid = SECINITSID_UNLABELED;
4180         sksec->sid = SECINITSID_UNLABELED;
4181         selinux_netlbl_sk_security_reset(sksec);
4182         sk->sk_security = sksec;
4183
4184         return 0;
4185 }
4186
4187 static void selinux_sk_free_security(struct sock *sk)
4188 {
4189         struct sk_security_struct *sksec = sk->sk_security;
4190
4191         sk->sk_security = NULL;
4192         selinux_netlbl_sk_security_free(sksec);
4193         kfree(sksec);
4194 }
4195
4196 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4197 {
4198         struct sk_security_struct *sksec = sk->sk_security;
4199         struct sk_security_struct *newsksec = newsk->sk_security;
4200
4201         newsksec->sid = sksec->sid;
4202         newsksec->peer_sid = sksec->peer_sid;
4203         newsksec->sclass = sksec->sclass;
4204
4205         selinux_netlbl_sk_security_reset(newsksec);
4206 }
4207
4208 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4209 {
4210         if (!sk)
4211                 *secid = SECINITSID_ANY_SOCKET;
4212         else {
4213                 struct sk_security_struct *sksec = sk->sk_security;
4214
4215                 *secid = sksec->sid;
4216         }
4217 }
4218
4219 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4220 {
4221         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4222         struct sk_security_struct *sksec = sk->sk_security;
4223
4224         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4225             sk->sk_family == PF_UNIX)
4226                 isec->sid = sksec->sid;
4227         sksec->sclass = isec->sclass;
4228 }
4229
4230 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4231                                      struct request_sock *req)
4232 {
4233         struct sk_security_struct *sksec = sk->sk_security;
4234         int err;
4235         u16 family = sk->sk_family;
4236         u32 newsid;
4237         u32 peersid;
4238
4239         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4240         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4241                 family = PF_INET;
4242
4243         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4244         if (err)
4245                 return err;
4246         if (peersid == SECSID_NULL) {
4247                 req->secid = sksec->sid;
4248                 req->peer_secid = SECSID_NULL;
4249         } else {
4250                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4251                 if (err)
4252                         return err;
4253                 req->secid = newsid;
4254                 req->peer_secid = peersid;
4255         }
4256
4257         return selinux_netlbl_inet_conn_request(req, family);
4258 }
4259
4260 static void selinux_inet_csk_clone(struct sock *newsk,
4261                                    const struct request_sock *req)
4262 {
4263         struct sk_security_struct *newsksec = newsk->sk_security;
4264
4265         newsksec->sid = req->secid;
4266         newsksec->peer_sid = req->peer_secid;
4267         /* NOTE: Ideally, we should also get the isec->sid for the
4268            new socket in sync, but we don't have the isec available yet.
4269            So we will wait until sock_graft to do it, by which
4270            time it will have been created and available. */
4271
4272         /* We don't need to take any sort of lock here as we are the only
4273          * thread with access to newsksec */
4274         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4275 }
4276
4277 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4278 {
4279         u16 family = sk->sk_family;
4280         struct sk_security_struct *sksec = sk->sk_security;
4281
4282         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4283         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4284                 family = PF_INET;
4285
4286         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4287 }
4288
4289 static void selinux_req_classify_flow(const struct request_sock *req,
4290                                       struct flowi *fl)
4291 {
4292         fl->secid = req->secid;
4293 }
4294
4295 static int selinux_tun_dev_create(void)
4296 {
4297         u32 sid = current_sid();
4298
4299         /* we aren't taking into account the "sockcreate" SID since the socket
4300          * that is being created here is not a socket in the traditional sense,
4301          * instead it is a private sock, accessible only to the kernel, and
4302          * representing a wide range of network traffic spanning multiple
4303          * connections unlike traditional sockets - check the TUN driver to
4304          * get a better understanding of why this socket is special */
4305
4306         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4307                             NULL);
4308 }
4309
4310 static void selinux_tun_dev_post_create(struct sock *sk)
4311 {
4312         struct sk_security_struct *sksec = sk->sk_security;
4313
4314         /* we don't currently perform any NetLabel based labeling here and it
4315          * isn't clear that we would want to do so anyway; while we could apply
4316          * labeling without the support of the TUN user the resulting labeled
4317          * traffic from the other end of the connection would almost certainly
4318          * cause confusion to the TUN user that had no idea network labeling
4319          * protocols were being used */
4320
4321         /* see the comments in selinux_tun_dev_create() about why we don't use
4322          * the sockcreate SID here */
4323
4324         sksec->sid = current_sid();
4325         sksec->sclass = SECCLASS_TUN_SOCKET;
4326 }
4327
4328 static int selinux_tun_dev_attach(struct sock *sk)
4329 {
4330         struct sk_security_struct *sksec = sk->sk_security;
4331         u32 sid = current_sid();
4332         int err;
4333
4334         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4335                            TUN_SOCKET__RELABELFROM, NULL);
4336         if (err)
4337                 return err;
4338         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4339                            TUN_SOCKET__RELABELTO, NULL);
4340         if (err)
4341                 return err;
4342
4343         sksec->sid = sid;
4344
4345         return 0;
4346 }
4347
4348 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4349 {
4350         int err = 0;
4351         u32 perm;
4352         struct nlmsghdr *nlh;
4353         struct sk_security_struct *sksec = sk->sk_security;
4354
4355         if (skb->len < NLMSG_SPACE(0)) {
4356                 err = -EINVAL;
4357                 goto out;
4358         }
4359         nlh = nlmsg_hdr(skb);
4360
4361         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4362         if (err) {
4363                 if (err == -EINVAL) {
4364                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4365                                   "SELinux:  unrecognized netlink message"
4366                                   " type=%hu for sclass=%hu\n",
4367                                   nlh->nlmsg_type, sksec->sclass);
4368                         if (!selinux_enforcing || security_get_allow_unknown())
4369                                 err = 0;
4370                 }
4371
4372                 /* Ignore */
4373                 if (err == -ENOENT)
4374                         err = 0;
4375                 goto out;
4376         }
4377
4378         err = sock_has_perm(current, sk, perm);
4379 out:
4380         return err;
4381 }
4382
4383 #ifdef CONFIG_NETFILTER
4384
4385 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4386                                        u16 family)
4387 {
4388         int err;
4389         char *addrp;
4390         u32 peer_sid;
4391         struct common_audit_data ad;
4392         u8 secmark_active;
4393         u8 netlbl_active;
4394         u8 peerlbl_active;
4395
4396         if (!selinux_policycap_netpeer)
4397                 return NF_ACCEPT;
4398
4399         secmark_active = selinux_secmark_enabled();
4400         netlbl_active = netlbl_enabled();
4401         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4402         if (!secmark_active && !peerlbl_active)
4403                 return NF_ACCEPT;
4404
4405         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4406                 return NF_DROP;
4407
4408         COMMON_AUDIT_DATA_INIT(&ad, NET);
4409         ad.u.net.netif = ifindex;
4410         ad.u.net.family = family;
4411         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4412                 return NF_DROP;
4413
4414         if (peerlbl_active) {
4415                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4416                                                peer_sid, &ad);
4417                 if (err) {
4418                         selinux_netlbl_err(skb, err, 1);
4419                         return NF_DROP;
4420                 }
4421         }
4422
4423         if (secmark_active)
4424                 if (avc_has_perm(peer_sid, skb->secmark,
4425                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4426                         return NF_DROP;
4427
4428         if (netlbl_active)
4429                 /* we do this in the FORWARD path and not the POST_ROUTING
4430                  * path because we want to make sure we apply the necessary
4431                  * labeling before IPsec is applied so we can leverage AH
4432                  * protection */
4433                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4434                         return NF_DROP;
4435
4436         return NF_ACCEPT;
4437 }
4438
4439 static unsigned int selinux_ipv4_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_INET);
4446 }
4447
4448 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4449 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4450                                          struct sk_buff *skb,
4451                                          const struct net_device *in,
4452                                          const struct net_device *out,
4453                                          int (*okfn)(struct sk_buff *))
4454 {
4455         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4456 }
4457 #endif  /* IPV6 */
4458
4459 static unsigned int selinux_ip_output(struct sk_buff *skb,
4460                                       u16 family)
4461 {
4462         u32 sid;
4463
4464         if (!netlbl_enabled())
4465                 return NF_ACCEPT;
4466
4467         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4468          * because we want to make sure we apply the necessary labeling
4469          * before IPsec is applied so we can leverage AH protection */
4470         if (skb->sk) {
4471                 struct sk_security_struct *sksec = skb->sk->sk_security;
4472                 sid = sksec->sid;
4473         } else
4474                 sid = SECINITSID_KERNEL;
4475         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4476                 return NF_DROP;
4477
4478         return NF_ACCEPT;
4479 }
4480
4481 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4482                                         struct sk_buff *skb,
4483                                         const struct net_device *in,
4484                                         const struct net_device *out,
4485                                         int (*okfn)(struct sk_buff *))
4486 {
4487         return selinux_ip_output(skb, PF_INET);
4488 }
4489
4490 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4491                                                 int ifindex,
4492                                                 u16 family)
4493 {
4494         struct sock *sk = skb->sk;
4495         struct sk_security_struct *sksec;
4496         struct common_audit_data ad;
4497         char *addrp;
4498         u8 proto;
4499
4500         if (sk == NULL)
4501                 return NF_ACCEPT;
4502         sksec = sk->sk_security;
4503
4504         COMMON_AUDIT_DATA_INIT(&ad, NET);
4505         ad.u.net.netif = ifindex;
4506         ad.u.net.family = family;
4507         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4508                 return NF_DROP;
4509
4510         if (selinux_secmark_enabled())
4511                 if (avc_has_perm(sksec->sid, skb->secmark,
4512                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4513                         return NF_DROP;
4514
4515         if (selinux_policycap_netpeer)
4516                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4517                         return NF_DROP;
4518
4519         return NF_ACCEPT;
4520 }
4521
4522 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4523                                          u16 family)
4524 {
4525         u32 secmark_perm;
4526         u32 peer_sid;
4527         struct sock *sk;
4528         struct common_audit_data ad;
4529         char *addrp;
4530         u8 secmark_active;
4531         u8 peerlbl_active;
4532
4533         /* If any sort of compatibility mode is enabled then handoff processing
4534          * to the selinux_ip_postroute_compat() function to deal with the
4535          * special handling.  We do this in an attempt to keep this function
4536          * as fast and as clean as possible. */
4537         if (!selinux_policycap_netpeer)
4538                 return selinux_ip_postroute_compat(skb, ifindex, family);
4539 #ifdef CONFIG_XFRM
4540         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4541          * packet transformation so allow the packet to pass without any checks
4542          * since we'll have another chance to perform access control checks
4543          * when the packet is on it's final way out.
4544          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4545          *       is NULL, in this case go ahead and apply access control. */
4546         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4547                 return NF_ACCEPT;
4548 #endif
4549         secmark_active = selinux_secmark_enabled();
4550         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4551         if (!secmark_active && !peerlbl_active)
4552                 return NF_ACCEPT;
4553
4554         /* if the packet is being forwarded then get the peer label from the
4555          * packet itself; otherwise check to see if it is from a local
4556          * application or the kernel, if from an application get the peer label
4557          * from the sending socket, otherwise use the kernel's sid */
4558         sk = skb->sk;
4559         if (sk == NULL) {
4560                 switch (family) {
4561                 case PF_INET:
4562                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4563                                 secmark_perm = PACKET__FORWARD_OUT;
4564                         else
4565                                 secmark_perm = PACKET__SEND;
4566                         break;
4567                 case PF_INET6:
4568                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4569                                 secmark_perm = PACKET__FORWARD_OUT;
4570                         else
4571                                 secmark_perm = PACKET__SEND;
4572                         break;
4573                 default:
4574                         return NF_DROP;
4575                 }
4576                 if (secmark_perm == PACKET__FORWARD_OUT) {
4577                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4578                                 return NF_DROP;
4579                 } else
4580                         peer_sid = SECINITSID_KERNEL;
4581         } else {
4582                 struct sk_security_struct *sksec = sk->sk_security;
4583                 peer_sid = sksec->sid;
4584                 secmark_perm = PACKET__SEND;
4585         }
4586
4587         COMMON_AUDIT_DATA_INIT(&ad, NET);
4588         ad.u.net.netif = ifindex;
4589         ad.u.net.family = family;
4590         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4591                 return NF_DROP;
4592
4593         if (secmark_active)
4594                 if (avc_has_perm(peer_sid, skb->secmark,
4595                                  SECCLASS_PACKET, secmark_perm, &ad))
4596                         return NF_DROP;
4597
4598         if (peerlbl_active) {
4599                 u32 if_sid;
4600                 u32 node_sid;
4601
4602                 if (sel_netif_sid(ifindex, &if_sid))
4603                         return NF_DROP;
4604                 if (avc_has_perm(peer_sid, if_sid,
4605                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4606                         return NF_DROP;
4607
4608                 if (sel_netnode_sid(addrp, family, &node_sid))
4609                         return NF_DROP;
4610                 if (avc_has_perm(peer_sid, node_sid,
4611                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4612                         return NF_DROP;
4613         }
4614
4615         return NF_ACCEPT;
4616 }
4617
4618 static unsigned int selinux_ipv4_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_INET);
4625 }
4626
4627 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4628 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4629                                            struct sk_buff *skb,
4630                                            const struct net_device *in,
4631                                            const struct net_device *out,
4632                                            int (*okfn)(struct sk_buff *))
4633 {
4634         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4635 }
4636 #endif  /* IPV6 */
4637
4638 #endif  /* CONFIG_NETFILTER */
4639
4640 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4641 {
4642         int err;
4643
4644         err = cap_netlink_send(sk, skb);
4645         if (err)
4646                 return err;
4647
4648         return selinux_nlmsg_perm(sk, skb);
4649 }
4650
4651 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4652 {
4653         int err;
4654         struct common_audit_data ad;
4655
4656         err = cap_netlink_recv(skb, capability);
4657         if (err)
4658                 return err;
4659
4660         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4661         ad.u.cap = capability;
4662
4663         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4664                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4665 }
4666
4667 static int ipc_alloc_security(struct task_struct *task,
4668                               struct kern_ipc_perm *perm,
4669                               u16 sclass)
4670 {
4671         struct ipc_security_struct *isec;
4672         u32 sid;
4673
4674         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4675         if (!isec)
4676                 return -ENOMEM;
4677
4678         sid = task_sid(task);
4679         isec->sclass = sclass;
4680         isec->sid = sid;
4681         perm->security = isec;
4682
4683         return 0;
4684 }
4685
4686 static void ipc_free_security(struct kern_ipc_perm *perm)
4687 {
4688         struct ipc_security_struct *isec = perm->security;
4689         perm->security = NULL;
4690         kfree(isec);
4691 }
4692
4693 static int msg_msg_alloc_security(struct msg_msg *msg)
4694 {
4695         struct msg_security_struct *msec;
4696
4697         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4698         if (!msec)
4699                 return -ENOMEM;
4700
4701         msec->sid = SECINITSID_UNLABELED;
4702         msg->security = msec;
4703
4704         return 0;
4705 }
4706
4707 static void msg_msg_free_security(struct msg_msg *msg)
4708 {
4709         struct msg_security_struct *msec = msg->security;
4710
4711         msg->security = NULL;
4712         kfree(msec);
4713 }
4714
4715 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4716                         u32 perms)
4717 {
4718         struct ipc_security_struct *isec;
4719         struct common_audit_data ad;
4720         u32 sid = current_sid();
4721
4722         isec = ipc_perms->security;
4723
4724         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4725         ad.u.ipc_id = ipc_perms->key;
4726
4727         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4728 }
4729
4730 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4731 {
4732         return msg_msg_alloc_security(msg);
4733 }
4734
4735 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4736 {
4737         msg_msg_free_security(msg);
4738 }
4739
4740 /* message queue security operations */
4741 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4742 {
4743         struct ipc_security_struct *isec;
4744         struct common_audit_data ad;
4745         u32 sid = current_sid();
4746         int rc;
4747
4748         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4749         if (rc)
4750                 return rc;
4751
4752         isec = msq->q_perm.security;
4753
4754         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4755         ad.u.ipc_id = msq->q_perm.key;
4756
4757         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4758                           MSGQ__CREATE, &ad);
4759         if (rc) {
4760                 ipc_free_security(&msq->q_perm);
4761                 return rc;
4762         }
4763         return 0;
4764 }
4765
4766 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4767 {
4768         ipc_free_security(&msq->q_perm);
4769 }
4770
4771 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4772 {
4773         struct ipc_security_struct *isec;
4774         struct common_audit_data ad;
4775         u32 sid = current_sid();
4776
4777         isec = msq->q_perm.security;
4778
4779         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4780         ad.u.ipc_id = msq->q_perm.key;
4781
4782         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4783                             MSGQ__ASSOCIATE, &ad);
4784 }
4785
4786 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4787 {
4788         int err;
4789         int perms;
4790
4791         switch (cmd) {
4792         case IPC_INFO:
4793         case MSG_INFO:
4794                 /* No specific object, just general system-wide information. */
4795                 return task_has_system(current, SYSTEM__IPC_INFO);
4796         case IPC_STAT:
4797         case MSG_STAT:
4798                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4799                 break;
4800         case IPC_SET:
4801                 perms = MSGQ__SETATTR;
4802                 break;
4803         case IPC_RMID:
4804                 perms = MSGQ__DESTROY;
4805                 break;
4806         default:
4807                 return 0;
4808         }
4809
4810         err = ipc_has_perm(&msq->q_perm, perms);
4811         return err;
4812 }
4813
4814 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4815 {
4816         struct ipc_security_struct *isec;
4817         struct msg_security_struct *msec;
4818         struct common_audit_data ad;
4819         u32 sid = current_sid();
4820         int rc;
4821
4822         isec = msq->q_perm.security;
4823         msec = msg->security;
4824
4825         /*
4826          * First time through, need to assign label to the message
4827          */
4828         if (msec->sid == SECINITSID_UNLABELED) {
4829                 /*
4830                  * Compute new sid based on current process and
4831                  * message queue this message will be stored in
4832                  */
4833                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4834                                              &msec->sid);
4835                 if (rc)
4836                         return rc;
4837         }
4838
4839         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4840         ad.u.ipc_id = msq->q_perm.key;
4841
4842         /* Can this process write to the queue? */
4843         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4844                           MSGQ__WRITE, &ad);
4845         if (!rc)
4846                 /* Can this process send the message */
4847                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4848                                   MSG__SEND, &ad);
4849         if (!rc)
4850                 /* Can the message be put in the queue? */
4851                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4852                                   MSGQ__ENQUEUE, &ad);
4853
4854         return rc;
4855 }
4856
4857 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4858                                     struct task_struct *target,
4859                                     long type, int mode)
4860 {
4861         struct ipc_security_struct *isec;
4862         struct msg_security_struct *msec;
4863         struct common_audit_data ad;
4864         u32 sid = task_sid(target);
4865         int rc;
4866
4867         isec = msq->q_perm.security;
4868         msec = msg->security;
4869
4870         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4871         ad.u.ipc_id = msq->q_perm.key;
4872
4873         rc = avc_has_perm(sid, isec->sid,
4874                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4875         if (!rc)
4876                 rc = avc_has_perm(sid, msec->sid,
4877                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4878         return rc;
4879 }
4880
4881 /* Shared Memory security operations */
4882 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4883 {
4884         struct ipc_security_struct *isec;
4885         struct common_audit_data ad;
4886         u32 sid = current_sid();
4887         int rc;
4888
4889         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4890         if (rc)
4891                 return rc;
4892
4893         isec = shp->shm_perm.security;
4894
4895         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4896         ad.u.ipc_id = shp->shm_perm.key;
4897
4898         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4899                           SHM__CREATE, &ad);
4900         if (rc) {
4901                 ipc_free_security(&shp->shm_perm);
4902                 return rc;
4903         }
4904         return 0;
4905 }
4906
4907 static void selinux_shm_free_security(struct shmid_kernel *shp)
4908 {
4909         ipc_free_security(&shp->shm_perm);
4910 }
4911
4912 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4913 {
4914         struct ipc_security_struct *isec;
4915         struct common_audit_data ad;
4916         u32 sid = current_sid();
4917
4918         isec = shp->shm_perm.security;
4919
4920         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4921         ad.u.ipc_id = shp->shm_perm.key;
4922
4923         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4924                             SHM__ASSOCIATE, &ad);
4925 }
4926
4927 /* Note, at this point, shp is locked down */
4928 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4929 {
4930         int perms;
4931         int err;
4932
4933         switch (cmd) {
4934         case IPC_INFO:
4935         case SHM_INFO:
4936                 /* No specific object, just general system-wide information. */
4937                 return task_has_system(current, SYSTEM__IPC_INFO);
4938         case IPC_STAT:
4939         case SHM_STAT:
4940                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4941                 break;
4942         case IPC_SET:
4943                 perms = SHM__SETATTR;
4944                 break;
4945         case SHM_LOCK:
4946         case SHM_UNLOCK:
4947                 perms = SHM__LOCK;
4948                 break;
4949         case IPC_RMID:
4950                 perms = SHM__DESTROY;
4951                 break;
4952         default:
4953                 return 0;
4954         }
4955
4956         err = ipc_has_perm(&shp->shm_perm, perms);
4957         return err;
4958 }
4959
4960 static int selinux_shm_shmat(struct shmid_kernel *shp,
4961                              char __user *shmaddr, int shmflg)
4962 {
4963         u32 perms;
4964
4965         if (shmflg & SHM_RDONLY)
4966                 perms = SHM__READ;
4967         else
4968                 perms = SHM__READ | SHM__WRITE;
4969
4970         return ipc_has_perm(&shp->shm_perm, perms);
4971 }
4972
4973 /* Semaphore security operations */
4974 static int selinux_sem_alloc_security(struct sem_array *sma)
4975 {
4976         struct ipc_security_struct *isec;
4977         struct common_audit_data ad;
4978         u32 sid = current_sid();
4979         int rc;
4980
4981         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4982         if (rc)
4983                 return rc;
4984
4985         isec = sma->sem_perm.security;
4986
4987         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4988         ad.u.ipc_id = sma->sem_perm.key;
4989
4990         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4991                           SEM__CREATE, &ad);
4992         if (rc) {
4993                 ipc_free_security(&sma->sem_perm);
4994                 return rc;
4995         }
4996         return 0;
4997 }
4998
4999 static void selinux_sem_free_security(struct sem_array *sma)
5000 {
5001         ipc_free_security(&sma->sem_perm);
5002 }
5003
5004 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5005 {
5006         struct ipc_security_struct *isec;
5007         struct common_audit_data ad;
5008         u32 sid = current_sid();
5009
5010         isec = sma->sem_perm.security;
5011
5012         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5013         ad.u.ipc_id = sma->sem_perm.key;
5014
5015         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5016                             SEM__ASSOCIATE, &ad);
5017 }
5018
5019 /* Note, at this point, sma is locked down */
5020 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5021 {
5022         int err;
5023         u32 perms;
5024
5025         switch (cmd) {
5026         case IPC_INFO:
5027         case SEM_INFO:
5028                 /* No specific object, just general system-wide information. */
5029                 return task_has_system(current, SYSTEM__IPC_INFO);
5030         case GETPID:
5031         case GETNCNT:
5032         case GETZCNT:
5033                 perms = SEM__GETATTR;
5034                 break;
5035         case GETVAL:
5036         case GETALL:
5037                 perms = SEM__READ;
5038                 break;
5039         case SETVAL:
5040         case SETALL:
5041                 perms = SEM__WRITE;
5042                 break;
5043         case IPC_RMID:
5044                 perms = SEM__DESTROY;
5045                 break;
5046         case IPC_SET:
5047                 perms = SEM__SETATTR;
5048                 break;
5049         case IPC_STAT:
5050         case SEM_STAT:
5051                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5052                 break;
5053         default:
5054                 return 0;
5055         }
5056
5057         err = ipc_has_perm(&sma->sem_perm, perms);
5058         return err;
5059 }
5060
5061 static int selinux_sem_semop(struct sem_array *sma,
5062                              struct sembuf *sops, unsigned nsops, int alter)
5063 {
5064         u32 perms;
5065
5066         if (alter)
5067                 perms = SEM__READ | SEM__WRITE;
5068         else
5069                 perms = SEM__READ;
5070
5071         return ipc_has_perm(&sma->sem_perm, perms);
5072 }
5073
5074 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5075 {
5076         u32 av = 0;
5077
5078         av = 0;
5079         if (flag & S_IRUGO)
5080                 av |= IPC__UNIX_READ;
5081         if (flag & S_IWUGO)
5082                 av |= IPC__UNIX_WRITE;
5083
5084         if (av == 0)
5085                 return 0;
5086
5087         return ipc_has_perm(ipcp, av);
5088 }
5089
5090 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5091 {
5092         struct ipc_security_struct *isec = ipcp->security;
5093         *secid = isec->sid;
5094 }
5095
5096 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5097 {
5098         if (inode)
5099                 inode_doinit_with_dentry(inode, dentry);
5100 }
5101
5102 static int selinux_getprocattr(struct task_struct *p,
5103                                char *name, char **value)
5104 {
5105         const struct task_security_struct *__tsec;
5106         u32 sid;
5107         int error;
5108         unsigned len;
5109
5110         if (current != p) {
5111                 error = current_has_perm(p, PROCESS__GETATTR);
5112                 if (error)
5113                         return error;
5114         }
5115
5116         rcu_read_lock();
5117         __tsec = __task_cred(p)->security;
5118
5119         if (!strcmp(name, "current"))
5120                 sid = __tsec->sid;
5121         else if (!strcmp(name, "prev"))
5122                 sid = __tsec->osid;
5123         else if (!strcmp(name, "exec"))
5124                 sid = __tsec->exec_sid;
5125         else if (!strcmp(name, "fscreate"))
5126                 sid = __tsec->create_sid;
5127         else if (!strcmp(name, "keycreate"))
5128                 sid = __tsec->keycreate_sid;
5129         else if (!strcmp(name, "sockcreate"))
5130                 sid = __tsec->sockcreate_sid;
5131         else
5132                 goto invalid;
5133         rcu_read_unlock();
5134
5135         if (!sid)
5136                 return 0;
5137
5138         error = security_sid_to_context(sid, value, &len);
5139         if (error)
5140                 return error;
5141         return len;
5142
5143 invalid:
5144         rcu_read_unlock();
5145         return -EINVAL;
5146 }
5147
5148 static int selinux_setprocattr(struct task_struct *p,
5149                                char *name, void *value, size_t size)
5150 {
5151         struct task_security_struct *tsec;
5152         struct task_struct *tracer;
5153         struct cred *new;
5154         u32 sid = 0, ptsid;
5155         int error;
5156         char *str = value;
5157
5158         if (current != p) {
5159                 /* SELinux only allows a process to change its own
5160                    security attributes. */
5161                 return -EACCES;
5162         }
5163
5164         /*
5165          * Basic control over ability to set these attributes at all.
5166          * current == p, but we'll pass them separately in case the
5167          * above restriction is ever removed.
5168          */
5169         if (!strcmp(name, "exec"))
5170                 error = current_has_perm(p, PROCESS__SETEXEC);
5171         else if (!strcmp(name, "fscreate"))
5172                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5173         else if (!strcmp(name, "keycreate"))
5174                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5175         else if (!strcmp(name, "sockcreate"))
5176                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5177         else if (!strcmp(name, "current"))
5178                 error = current_has_perm(p, PROCESS__SETCURRENT);
5179         else
5180                 error = -EINVAL;
5181         if (error)
5182                 return error;
5183
5184         /* Obtain a SID for the context, if one was specified. */
5185         if (size && str[1] && str[1] != '\n') {
5186                 if (str[size-1] == '\n') {
5187                         str[size-1] = 0;
5188                         size--;
5189                 }
5190                 error = security_context_to_sid(value, size, &sid);
5191                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5192                         if (!capable(CAP_MAC_ADMIN))
5193                                 return error;
5194                         error = security_context_to_sid_force(value, size,
5195                                                               &sid);
5196                 }
5197                 if (error)
5198                         return error;
5199         }
5200
5201         new = prepare_creds();
5202         if (!new)
5203                 return -ENOMEM;
5204
5205         /* Permission checking based on the specified context is
5206            performed during the actual operation (execve,
5207            open/mkdir/...), when we know the full context of the
5208            operation.  See selinux_bprm_set_creds for the execve
5209            checks and may_create for the file creation checks. The
5210            operation will then fail if the context is not permitted. */
5211         tsec = new->security;
5212         if (!strcmp(name, "exec")) {
5213                 tsec->exec_sid = sid;
5214         } else if (!strcmp(name, "fscreate")) {
5215                 tsec->create_sid = sid;
5216         } else if (!strcmp(name, "keycreate")) {
5217                 error = may_create_key(sid, p);
5218                 if (error)
5219                         goto abort_change;
5220                 tsec->keycreate_sid = sid;
5221         } else if (!strcmp(name, "sockcreate")) {
5222                 tsec->sockcreate_sid = sid;
5223         } else if (!strcmp(name, "current")) {
5224                 error = -EINVAL;
5225                 if (sid == 0)
5226                         goto abort_change;
5227
5228                 /* Only allow single threaded processes to change context */
5229                 error = -EPERM;
5230                 if (!current_is_single_threaded()) {
5231                         error = security_bounded_transition(tsec->sid, sid);
5232                         if (error)
5233                                 goto abort_change;
5234                 }
5235
5236                 /* Check permissions for the transition. */
5237                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5238                                      PROCESS__DYNTRANSITION, NULL);
5239                 if (error)
5240                         goto abort_change;
5241
5242                 /* Check for ptracing, and update the task SID if ok.
5243                    Otherwise, leave SID unchanged and fail. */
5244                 ptsid = 0;
5245                 task_lock(p);
5246                 tracer = tracehook_tracer_task(p);
5247                 if (tracer)
5248                         ptsid = task_sid(tracer);
5249                 task_unlock(p);
5250
5251                 if (tracer) {
5252                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5253                                              PROCESS__PTRACE, NULL);
5254                         if (error)
5255                                 goto abort_change;
5256                 }
5257
5258                 tsec->sid = sid;
5259         } else {
5260                 error = -EINVAL;
5261                 goto abort_change;
5262         }
5263
5264         commit_creds(new);
5265         return size;
5266
5267 abort_change:
5268         abort_creds(new);
5269         return error;
5270 }
5271
5272 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5273 {
5274         return security_sid_to_context(secid, secdata, seclen);
5275 }
5276
5277 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5278 {
5279         return security_context_to_sid(secdata, seclen, secid);
5280 }
5281
5282 static void selinux_release_secctx(char *secdata, u32 seclen)
5283 {
5284         kfree(secdata);
5285 }
5286
5287 /*
5288  *      called with inode->i_mutex locked
5289  */
5290 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5291 {
5292         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5293 }
5294
5295 /*
5296  *      called with inode->i_mutex locked
5297  */
5298 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5299 {
5300         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5301 }
5302
5303 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5304 {
5305         int len = 0;
5306         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5307                                                 ctx, true);
5308         if (len < 0)
5309                 return len;
5310         *ctxlen = len;
5311         return 0;
5312 }
5313 #ifdef CONFIG_KEYS
5314
5315 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5316                              unsigned long flags)
5317 {
5318         const struct task_security_struct *tsec;
5319         struct key_security_struct *ksec;
5320
5321         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5322         if (!ksec)
5323                 return -ENOMEM;
5324
5325         tsec = cred->security;
5326         if (tsec->keycreate_sid)
5327                 ksec->sid = tsec->keycreate_sid;
5328         else
5329                 ksec->sid = tsec->sid;
5330
5331         k->security = ksec;
5332         return 0;
5333 }
5334
5335 static void selinux_key_free(struct key *k)
5336 {
5337         struct key_security_struct *ksec = k->security;
5338
5339         k->security = NULL;
5340         kfree(ksec);
5341 }
5342
5343 static int selinux_key_permission(key_ref_t key_ref,
5344                                   const struct cred *cred,
5345                                   key_perm_t perm)
5346 {
5347         struct key *key;
5348         struct key_security_struct *ksec;
5349         u32 sid;
5350
5351         /* if no specific permissions are requested, we skip the
5352            permission check. No serious, additional covert channels
5353            appear to be created. */
5354         if (perm == 0)
5355                 return 0;
5356
5357         sid = cred_sid(cred);
5358
5359         key = key_ref_to_ptr(key_ref);
5360         ksec = key->security;
5361
5362         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5363 }
5364
5365 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5366 {
5367         struct key_security_struct *ksec = key->security;
5368         char *context = NULL;
5369         unsigned len;
5370         int rc;
5371
5372         rc = security_sid_to_context(ksec->sid, &context, &len);
5373         if (!rc)
5374                 rc = len;
5375         *_buffer = context;
5376         return rc;
5377 }
5378
5379 #endif
5380
5381 static struct security_operations selinux_ops = {
5382         .name =                         "selinux",
5383
5384         .ptrace_access_check =          selinux_ptrace_access_check,
5385         .ptrace_traceme =               selinux_ptrace_traceme,
5386         .capget =                       selinux_capget,
5387         .capset =                       selinux_capset,
5388         .sysctl =                       selinux_sysctl,
5389         .capable =                      selinux_capable,
5390         .quotactl =                     selinux_quotactl,
5391         .quota_on =                     selinux_quota_on,
5392         .syslog =                       selinux_syslog,
5393         .vm_enough_memory =             selinux_vm_enough_memory,
5394
5395         .netlink_send =                 selinux_netlink_send,
5396         .netlink_recv =                 selinux_netlink_recv,
5397
5398         .bprm_set_creds =               selinux_bprm_set_creds,
5399         .bprm_committing_creds =        selinux_bprm_committing_creds,
5400         .bprm_committed_creds =         selinux_bprm_committed_creds,
5401         .bprm_secureexec =              selinux_bprm_secureexec,
5402
5403         .sb_alloc_security =            selinux_sb_alloc_security,
5404         .sb_free_security =             selinux_sb_free_security,
5405         .sb_copy_data =                 selinux_sb_copy_data,
5406         .sb_kern_mount =                selinux_sb_kern_mount,
5407         .sb_show_options =              selinux_sb_show_options,
5408         .sb_statfs =                    selinux_sb_statfs,
5409         .sb_mount =                     selinux_mount,
5410         .sb_umount =                    selinux_umount,
5411         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5412         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5413         .sb_parse_opts_str =            selinux_parse_opts_str,
5414
5415
5416         .inode_alloc_security =         selinux_inode_alloc_security,
5417         .inode_free_security =          selinux_inode_free_security,
5418         .inode_init_security =          selinux_inode_init_security,
5419         .inode_create =                 selinux_inode_create,
5420         .inode_link =                   selinux_inode_link,
5421         .inode_unlink =                 selinux_inode_unlink,
5422         .inode_symlink =                selinux_inode_symlink,
5423         .inode_mkdir =                  selinux_inode_mkdir,
5424         .inode_rmdir =                  selinux_inode_rmdir,
5425         .inode_mknod =                  selinux_inode_mknod,
5426         .inode_rename =                 selinux_inode_rename,
5427         .inode_readlink =               selinux_inode_readlink,
5428         .inode_follow_link =            selinux_inode_follow_link,
5429         .inode_permission =             selinux_inode_permission,
5430         .inode_setattr =                selinux_inode_setattr,
5431         .inode_getattr =                selinux_inode_getattr,
5432         .inode_setxattr =               selinux_inode_setxattr,
5433         .inode_post_setxattr =          selinux_inode_post_setxattr,
5434         .inode_getxattr =               selinux_inode_getxattr,
5435         .inode_listxattr =              selinux_inode_listxattr,
5436         .inode_removexattr =            selinux_inode_removexattr,
5437         .inode_getsecurity =            selinux_inode_getsecurity,
5438         .inode_setsecurity =            selinux_inode_setsecurity,
5439         .inode_listsecurity =           selinux_inode_listsecurity,
5440         .inode_getsecid =               selinux_inode_getsecid,
5441
5442         .file_permission =              selinux_file_permission,
5443         .file_alloc_security =          selinux_file_alloc_security,
5444         .file_free_security =           selinux_file_free_security,
5445         .file_ioctl =                   selinux_file_ioctl,
5446         .file_mmap =                    selinux_file_mmap,
5447         .file_mprotect =                selinux_file_mprotect,
5448         .file_lock =                    selinux_file_lock,
5449         .file_fcntl =                   selinux_file_fcntl,
5450         .file_set_fowner =              selinux_file_set_fowner,
5451         .file_send_sigiotask =          selinux_file_send_sigiotask,
5452         .file_receive =                 selinux_file_receive,
5453
5454         .dentry_open =                  selinux_dentry_open,
5455
5456         .task_create =                  selinux_task_create,
5457         .cred_alloc_blank =             selinux_cred_alloc_blank,
5458         .cred_free =                    selinux_cred_free,
5459         .cred_prepare =                 selinux_cred_prepare,
5460         .cred_transfer =                selinux_cred_transfer,
5461         .kernel_act_as =                selinux_kernel_act_as,
5462         .kernel_create_files_as =       selinux_kernel_create_files_as,
5463         .kernel_module_request =        selinux_kernel_module_request,
5464         .task_setpgid =                 selinux_task_setpgid,
5465         .task_getpgid =                 selinux_task_getpgid,
5466         .task_getsid =                  selinux_task_getsid,
5467         .task_getsecid =                selinux_task_getsecid,
5468         .task_setnice =                 selinux_task_setnice,
5469         .task_setioprio =               selinux_task_setioprio,
5470         .task_getioprio =               selinux_task_getioprio,
5471         .task_setrlimit =               selinux_task_setrlimit,
5472         .task_setscheduler =            selinux_task_setscheduler,
5473         .task_getscheduler =            selinux_task_getscheduler,
5474         .task_movememory =              selinux_task_movememory,
5475         .task_kill =                    selinux_task_kill,
5476         .task_wait =                    selinux_task_wait,
5477         .task_to_inode =                selinux_task_to_inode,
5478
5479         .ipc_permission =               selinux_ipc_permission,
5480         .ipc_getsecid =                 selinux_ipc_getsecid,
5481
5482         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5483         .msg_msg_free_security =        selinux_msg_msg_free_security,
5484
5485         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5486         .msg_queue_free_security =      selinux_msg_queue_free_security,
5487         .msg_queue_associate =          selinux_msg_queue_associate,
5488         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5489         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5490         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5491
5492         .shm_alloc_security =           selinux_shm_alloc_security,
5493         .shm_free_security =            selinux_shm_free_security,
5494         .shm_associate =                selinux_shm_associate,
5495         .shm_shmctl =                   selinux_shm_shmctl,
5496         .shm_shmat =                    selinux_shm_shmat,
5497
5498         .sem_alloc_security =           selinux_sem_alloc_security,
5499         .sem_free_security =            selinux_sem_free_security,
5500         .sem_associate =                selinux_sem_associate,
5501         .sem_semctl =                   selinux_sem_semctl,
5502         .sem_semop =                    selinux_sem_semop,
5503
5504         .d_instantiate =                selinux_d_instantiate,
5505
5506         .getprocattr =                  selinux_getprocattr,
5507         .setprocattr =                  selinux_setprocattr,
5508
5509         .secid_to_secctx =              selinux_secid_to_secctx,
5510         .secctx_to_secid =              selinux_secctx_to_secid,
5511         .release_secctx =               selinux_release_secctx,
5512         .inode_notifysecctx =           selinux_inode_notifysecctx,
5513         .inode_setsecctx =              selinux_inode_setsecctx,
5514         .inode_getsecctx =              selinux_inode_getsecctx,
5515
5516         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5517         .unix_may_send =                selinux_socket_unix_may_send,
5518
5519         .socket_create =                selinux_socket_create,
5520         .socket_post_create =           selinux_socket_post_create,
5521         .socket_bind =                  selinux_socket_bind,
5522         .socket_connect =               selinux_socket_connect,
5523         .socket_listen =                selinux_socket_listen,
5524         .socket_accept =                selinux_socket_accept,
5525         .socket_sendmsg =               selinux_socket_sendmsg,
5526         .socket_recvmsg =               selinux_socket_recvmsg,
5527         .socket_getsockname =           selinux_socket_getsockname,
5528         .socket_getpeername =           selinux_socket_getpeername,
5529         .socket_getsockopt =            selinux_socket_getsockopt,
5530         .socket_setsockopt =            selinux_socket_setsockopt,
5531         .socket_shutdown =              selinux_socket_shutdown,
5532         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5533         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5534         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5535         .sk_alloc_security =            selinux_sk_alloc_security,
5536         .sk_free_security =             selinux_sk_free_security,
5537         .sk_clone_security =            selinux_sk_clone_security,
5538         .sk_getsecid =                  selinux_sk_getsecid,
5539         .sock_graft =                   selinux_sock_graft,
5540         .inet_conn_request =            selinux_inet_conn_request,
5541         .inet_csk_clone =               selinux_inet_csk_clone,
5542         .inet_conn_established =        selinux_inet_conn_established,
5543         .req_classify_flow =            selinux_req_classify_flow,
5544         .tun_dev_create =               selinux_tun_dev_create,
5545         .tun_dev_post_create =          selinux_tun_dev_post_create,
5546         .tun_dev_attach =               selinux_tun_dev_attach,
5547
5548 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5549         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5550         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5551         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5552         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5553         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5554         .xfrm_state_free_security =     selinux_xfrm_state_free,
5555         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5556         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5557         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5558         .xfrm_decode_session =          selinux_xfrm_decode_session,
5559 #endif
5560
5561 #ifdef CONFIG_KEYS
5562         .key_alloc =                    selinux_key_alloc,
5563         .key_free =                     selinux_key_free,
5564         .key_permission =               selinux_key_permission,
5565         .key_getsecurity =              selinux_key_getsecurity,
5566 #endif
5567
5568 #ifdef CONFIG_AUDIT
5569         .audit_rule_init =              selinux_audit_rule_init,
5570         .audit_rule_known =             selinux_audit_rule_known,
5571         .audit_rule_match =             selinux_audit_rule_match,
5572         .audit_rule_free =              selinux_audit_rule_free,
5573 #endif
5574 };
5575
5576 static __init int selinux_init(void)
5577 {
5578         if (!security_module_enable(&selinux_ops)) {
5579                 selinux_enabled = 0;
5580                 return 0;
5581         }
5582
5583         if (!selinux_enabled) {
5584                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5585                 return 0;
5586         }
5587
5588         printk(KERN_INFO "SELinux:  Initializing.\n");
5589
5590         /* Set the security state for the initial task. */
5591         cred_init_security();
5592
5593         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5594
5595         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5596                                             sizeof(struct inode_security_struct),
5597                                             0, SLAB_PANIC, NULL);
5598         avc_init();
5599
5600         if (register_security(&selinux_ops))
5601                 panic("SELinux: Unable to register with kernel.\n");
5602
5603         if (selinux_enforcing)
5604                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5605         else
5606                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5607
5608         return 0;
5609 }
5610
5611 static void delayed_superblock_init(struct super_block *sb, void *unused)
5612 {
5613         superblock_doinit(sb, NULL);
5614 }
5615
5616 void selinux_complete_init(void)
5617 {
5618         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5619
5620         /* Set up any superblocks initialized prior to the policy load. */
5621         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5622         iterate_supers(delayed_superblock_init, NULL);
5623 }
5624
5625 /* SELinux requires early initialization in order to label
5626    all processes and objects when they are created. */
5627 security_initcall(selinux_init);
5628
5629 #if defined(CONFIG_NETFILTER)
5630
5631 static struct nf_hook_ops selinux_ipv4_ops[] = {
5632         {
5633                 .hook =         selinux_ipv4_postroute,
5634                 .owner =        THIS_MODULE,
5635                 .pf =           PF_INET,
5636                 .hooknum =      NF_INET_POST_ROUTING,
5637                 .priority =     NF_IP_PRI_SELINUX_LAST,
5638         },
5639         {
5640                 .hook =         selinux_ipv4_forward,
5641                 .owner =        THIS_MODULE,
5642                 .pf =           PF_INET,
5643                 .hooknum =      NF_INET_FORWARD,
5644                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5645         },
5646         {
5647                 .hook =         selinux_ipv4_output,
5648                 .owner =        THIS_MODULE,
5649                 .pf =           PF_INET,
5650                 .hooknum =      NF_INET_LOCAL_OUT,
5651                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5652         }
5653 };
5654
5655 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5656
5657 static struct nf_hook_ops selinux_ipv6_ops[] = {
5658         {
5659                 .hook =         selinux_ipv6_postroute,
5660                 .owner =        THIS_MODULE,
5661                 .pf =           PF_INET6,
5662                 .hooknum =      NF_INET_POST_ROUTING,
5663                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5664         },
5665         {
5666                 .hook =         selinux_ipv6_forward,
5667                 .owner =        THIS_MODULE,
5668                 .pf =           PF_INET6,
5669                 .hooknum =      NF_INET_FORWARD,
5670                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5671         }
5672 };
5673
5674 #endif  /* IPV6 */
5675
5676 static int __init selinux_nf_ip_init(void)
5677 {
5678         int err = 0;
5679
5680         if (!selinux_enabled)
5681                 goto out;
5682
5683         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5684
5685         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5686         if (err)
5687                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5688
5689 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5690         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5691         if (err)
5692                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5693 #endif  /* IPV6 */
5694
5695 out:
5696         return err;
5697 }
5698
5699 __initcall(selinux_nf_ip_init);
5700
5701 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5702 static void selinux_nf_ip_exit(void)
5703 {
5704         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5705
5706         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5707 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5708         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5709 #endif  /* IPV6 */
5710 }
5711 #endif
5712
5713 #else /* CONFIG_NETFILTER */
5714
5715 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5716 #define selinux_nf_ip_exit()
5717 #endif
5718
5719 #endif /* CONFIG_NETFILTER */
5720
5721 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5722 static int selinux_disabled;
5723
5724 int selinux_disable(void)
5725 {
5726         extern void exit_sel_fs(void);
5727
5728         if (ss_initialized) {
5729                 /* Not permitted after initial policy load. */
5730                 return -EINVAL;
5731         }
5732
5733         if (selinux_disabled) {
5734                 /* Only do this once. */
5735                 return -EINVAL;
5736         }
5737
5738         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5739
5740         selinux_disabled = 1;
5741         selinux_enabled = 0;
5742
5743         reset_security_ops();
5744
5745         /* Try to destroy the avc node cache */
5746         avc_disable();
5747
5748         /* Unregister netfilter hooks. */
5749         selinux_nf_ip_exit();
5750
5751         /* Unregister selinuxfs. */
5752         exit_sel_fs();
5753
5754         return 0;
5755 }
5756 #endif