timers: fix itimer/many thread hang
[safe/jmp/linux-2.6] / 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 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
80 #include "avc.h"
81 #include "objsec.h"
82 #include "netif.h"
83 #include "netnode.h"
84 #include "netport.h"
85 #include "xfrm.h"
86 #include "netlabel.h"
87 #include "audit.h"
88
89 #define XATTR_SELINUX_SUFFIX "selinux"
90 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
91
92 #define NUM_SEL_MNT_OPTS 4
93
94 extern unsigned int policydb_loaded_version;
95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96 extern int selinux_compat_net;
97 extern struct security_operations *security_ops;
98
99 /* SECMARK reference count */
100 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
101
102 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
103 int selinux_enforcing;
104
105 static int __init enforcing_setup(char *str)
106 {
107         unsigned long enforcing;
108         if (!strict_strtoul(str, 0, &enforcing))
109                 selinux_enforcing = enforcing ? 1 : 0;
110         return 1;
111 }
112 __setup("enforcing=", enforcing_setup);
113 #endif
114
115 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
116 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
117
118 static int __init selinux_enabled_setup(char *str)
119 {
120         unsigned long enabled;
121         if (!strict_strtoul(str, 0, &enabled))
122                 selinux_enabled = enabled ? 1 : 0;
123         return 1;
124 }
125 __setup("selinux=", selinux_enabled_setup);
126 #else
127 int selinux_enabled = 1;
128 #endif
129
130
131 /*
132  * Minimal support for a secondary security module,
133  * just to allow the use of the capability module.
134  */
135 static struct security_operations *secondary_ops;
136
137 /* Lists of inode and superblock security structures initialized
138    before the policy was loaded. */
139 static LIST_HEAD(superblock_security_head);
140 static DEFINE_SPINLOCK(sb_security_lock);
141
142 static struct kmem_cache *sel_inode_cache;
143
144 /**
145  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
146  *
147  * Description:
148  * This function checks the SECMARK reference counter to see if any SECMARK
149  * targets are currently configured, if the reference counter is greater than
150  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
151  * enabled, false (0) if SECMARK is disabled.
152  *
153  */
154 static int selinux_secmark_enabled(void)
155 {
156         return (atomic_read(&selinux_secmark_refcount) > 0);
157 }
158
159 /* Allocate and free functions for each kind of security blob. */
160
161 static int task_alloc_security(struct task_struct *task)
162 {
163         struct task_security_struct *tsec;
164
165         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
166         if (!tsec)
167                 return -ENOMEM;
168
169         tsec->osid = tsec->sid = SECINITSID_UNLABELED;
170         task->security = tsec;
171
172         return 0;
173 }
174
175 static void task_free_security(struct task_struct *task)
176 {
177         struct task_security_struct *tsec = task->security;
178         task->security = NULL;
179         kfree(tsec);
180 }
181
182 static int inode_alloc_security(struct inode *inode)
183 {
184         struct task_security_struct *tsec = current->security;
185         struct inode_security_struct *isec;
186
187         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
188         if (!isec)
189                 return -ENOMEM;
190
191         mutex_init(&isec->lock);
192         INIT_LIST_HEAD(&isec->list);
193         isec->inode = inode;
194         isec->sid = SECINITSID_UNLABELED;
195         isec->sclass = SECCLASS_FILE;
196         isec->task_sid = tsec->sid;
197         inode->i_security = isec;
198
199         return 0;
200 }
201
202 static void inode_free_security(struct inode *inode)
203 {
204         struct inode_security_struct *isec = inode->i_security;
205         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
206
207         spin_lock(&sbsec->isec_lock);
208         if (!list_empty(&isec->list))
209                 list_del_init(&isec->list);
210         spin_unlock(&sbsec->isec_lock);
211
212         inode->i_security = NULL;
213         kmem_cache_free(sel_inode_cache, isec);
214 }
215
216 static int file_alloc_security(struct file *file)
217 {
218         struct task_security_struct *tsec = current->security;
219         struct file_security_struct *fsec;
220
221         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
222         if (!fsec)
223                 return -ENOMEM;
224
225         fsec->sid = tsec->sid;
226         fsec->fown_sid = tsec->sid;
227         file->f_security = fsec;
228
229         return 0;
230 }
231
232 static void file_free_security(struct file *file)
233 {
234         struct file_security_struct *fsec = file->f_security;
235         file->f_security = NULL;
236         kfree(fsec);
237 }
238
239 static int superblock_alloc_security(struct super_block *sb)
240 {
241         struct superblock_security_struct *sbsec;
242
243         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
244         if (!sbsec)
245                 return -ENOMEM;
246
247         mutex_init(&sbsec->lock);
248         INIT_LIST_HEAD(&sbsec->list);
249         INIT_LIST_HEAD(&sbsec->isec_head);
250         spin_lock_init(&sbsec->isec_lock);
251         sbsec->sb = sb;
252         sbsec->sid = SECINITSID_UNLABELED;
253         sbsec->def_sid = SECINITSID_FILE;
254         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
255         sb->s_security = sbsec;
256
257         return 0;
258 }
259
260 static void superblock_free_security(struct super_block *sb)
261 {
262         struct superblock_security_struct *sbsec = sb->s_security;
263
264         spin_lock(&sb_security_lock);
265         if (!list_empty(&sbsec->list))
266                 list_del_init(&sbsec->list);
267         spin_unlock(&sb_security_lock);
268
269         sb->s_security = NULL;
270         kfree(sbsec);
271 }
272
273 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
274 {
275         struct sk_security_struct *ssec;
276
277         ssec = kzalloc(sizeof(*ssec), priority);
278         if (!ssec)
279                 return -ENOMEM;
280
281         ssec->peer_sid = SECINITSID_UNLABELED;
282         ssec->sid = SECINITSID_UNLABELED;
283         sk->sk_security = ssec;
284
285         selinux_netlbl_sk_security_reset(ssec, family);
286
287         return 0;
288 }
289
290 static void sk_free_security(struct sock *sk)
291 {
292         struct sk_security_struct *ssec = sk->sk_security;
293
294         sk->sk_security = NULL;
295         kfree(ssec);
296 }
297
298 /* The security server must be initialized before
299    any labeling or access decisions can be provided. */
300 extern int ss_initialized;
301
302 /* The file system's label must be initialized prior to use. */
303
304 static char *labeling_behaviors[6] = {
305         "uses xattr",
306         "uses transition SIDs",
307         "uses task SIDs",
308         "uses genfs_contexts",
309         "not configured for labeling",
310         "uses mountpoint labeling",
311 };
312
313 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
314
315 static inline int inode_doinit(struct inode *inode)
316 {
317         return inode_doinit_with_dentry(inode, NULL);
318 }
319
320 enum {
321         Opt_error = -1,
322         Opt_context = 1,
323         Opt_fscontext = 2,
324         Opt_defcontext = 3,
325         Opt_rootcontext = 4,
326 };
327
328 static match_table_t tokens = {
329         {Opt_context, CONTEXT_STR "%s"},
330         {Opt_fscontext, FSCONTEXT_STR "%s"},
331         {Opt_defcontext, DEFCONTEXT_STR "%s"},
332         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
333         {Opt_error, NULL},
334 };
335
336 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
337
338 static int may_context_mount_sb_relabel(u32 sid,
339                         struct superblock_security_struct *sbsec,
340                         struct task_security_struct *tsec)
341 {
342         int rc;
343
344         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
345                           FILESYSTEM__RELABELFROM, NULL);
346         if (rc)
347                 return rc;
348
349         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
350                           FILESYSTEM__RELABELTO, NULL);
351         return rc;
352 }
353
354 static int may_context_mount_inode_relabel(u32 sid,
355                         struct superblock_security_struct *sbsec,
356                         struct task_security_struct *tsec)
357 {
358         int rc;
359         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
360                           FILESYSTEM__RELABELFROM, NULL);
361         if (rc)
362                 return rc;
363
364         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
365                           FILESYSTEM__ASSOCIATE, NULL);
366         return rc;
367 }
368
369 static int sb_finish_set_opts(struct super_block *sb)
370 {
371         struct superblock_security_struct *sbsec = sb->s_security;
372         struct dentry *root = sb->s_root;
373         struct inode *root_inode = root->d_inode;
374         int rc = 0;
375
376         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
377                 /* Make sure that the xattr handler exists and that no
378                    error other than -ENODATA is returned by getxattr on
379                    the root directory.  -ENODATA is ok, as this may be
380                    the first boot of the SELinux kernel before we have
381                    assigned xattr values to the filesystem. */
382                 if (!root_inode->i_op->getxattr) {
383                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
384                                "xattr support\n", sb->s_id, sb->s_type->name);
385                         rc = -EOPNOTSUPP;
386                         goto out;
387                 }
388                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
389                 if (rc < 0 && rc != -ENODATA) {
390                         if (rc == -EOPNOTSUPP)
391                                 printk(KERN_WARNING "SELinux: (dev %s, type "
392                                        "%s) has no security xattr handler\n",
393                                        sb->s_id, sb->s_type->name);
394                         else
395                                 printk(KERN_WARNING "SELinux: (dev %s, type "
396                                        "%s) getxattr errno %d\n", sb->s_id,
397                                        sb->s_type->name, -rc);
398                         goto out;
399                 }
400         }
401
402         sbsec->initialized = 1;
403
404         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
405                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
406                        sb->s_id, sb->s_type->name);
407         else
408                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
409                        sb->s_id, sb->s_type->name,
410                        labeling_behaviors[sbsec->behavior-1]);
411
412         /* Initialize the root inode. */
413         rc = inode_doinit_with_dentry(root_inode, root);
414
415         /* Initialize any other inodes associated with the superblock, e.g.
416            inodes created prior to initial policy load or inodes created
417            during get_sb by a pseudo filesystem that directly
418            populates itself. */
419         spin_lock(&sbsec->isec_lock);
420 next_inode:
421         if (!list_empty(&sbsec->isec_head)) {
422                 struct inode_security_struct *isec =
423                                 list_entry(sbsec->isec_head.next,
424                                            struct inode_security_struct, list);
425                 struct inode *inode = isec->inode;
426                 spin_unlock(&sbsec->isec_lock);
427                 inode = igrab(inode);
428                 if (inode) {
429                         if (!IS_PRIVATE(inode))
430                                 inode_doinit(inode);
431                         iput(inode);
432                 }
433                 spin_lock(&sbsec->isec_lock);
434                 list_del_init(&isec->list);
435                 goto next_inode;
436         }
437         spin_unlock(&sbsec->isec_lock);
438 out:
439         return rc;
440 }
441
442 /*
443  * This function should allow an FS to ask what it's mount security
444  * options were so it can use those later for submounts, displaying
445  * mount options, or whatever.
446  */
447 static int selinux_get_mnt_opts(const struct super_block *sb,
448                                 struct security_mnt_opts *opts)
449 {
450         int rc = 0, i;
451         struct superblock_security_struct *sbsec = sb->s_security;
452         char *context = NULL;
453         u32 len;
454         char tmp;
455
456         security_init_mnt_opts(opts);
457
458         if (!sbsec->initialized)
459                 return -EINVAL;
460
461         if (!ss_initialized)
462                 return -EINVAL;
463
464         /*
465          * if we ever use sbsec flags for anything other than tracking mount
466          * settings this is going to need a mask
467          */
468         tmp = sbsec->flags;
469         /* count the number of mount options for this sb */
470         for (i = 0; i < 8; i++) {
471                 if (tmp & 0x01)
472                         opts->num_mnt_opts++;
473                 tmp >>= 1;
474         }
475
476         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
477         if (!opts->mnt_opts) {
478                 rc = -ENOMEM;
479                 goto out_free;
480         }
481
482         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
483         if (!opts->mnt_opts_flags) {
484                 rc = -ENOMEM;
485                 goto out_free;
486         }
487
488         i = 0;
489         if (sbsec->flags & FSCONTEXT_MNT) {
490                 rc = security_sid_to_context(sbsec->sid, &context, &len);
491                 if (rc)
492                         goto out_free;
493                 opts->mnt_opts[i] = context;
494                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
495         }
496         if (sbsec->flags & CONTEXT_MNT) {
497                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
498                 if (rc)
499                         goto out_free;
500                 opts->mnt_opts[i] = context;
501                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
502         }
503         if (sbsec->flags & DEFCONTEXT_MNT) {
504                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
505                 if (rc)
506                         goto out_free;
507                 opts->mnt_opts[i] = context;
508                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
509         }
510         if (sbsec->flags & ROOTCONTEXT_MNT) {
511                 struct inode *root = sbsec->sb->s_root->d_inode;
512                 struct inode_security_struct *isec = root->i_security;
513
514                 rc = security_sid_to_context(isec->sid, &context, &len);
515                 if (rc)
516                         goto out_free;
517                 opts->mnt_opts[i] = context;
518                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
519         }
520
521         BUG_ON(i != opts->num_mnt_opts);
522
523         return 0;
524
525 out_free:
526         security_free_mnt_opts(opts);
527         return rc;
528 }
529
530 static int bad_option(struct superblock_security_struct *sbsec, char flag,
531                       u32 old_sid, u32 new_sid)
532 {
533         /* check if the old mount command had the same options */
534         if (sbsec->initialized)
535                 if (!(sbsec->flags & flag) ||
536                     (old_sid != new_sid))
537                         return 1;
538
539         /* check if we were passed the same options twice,
540          * aka someone passed context=a,context=b
541          */
542         if (!sbsec->initialized)
543                 if (sbsec->flags & flag)
544                         return 1;
545         return 0;
546 }
547
548 /*
549  * Allow filesystems with binary mount data to explicitly set mount point
550  * labeling information.
551  */
552 static int selinux_set_mnt_opts(struct super_block *sb,
553                                 struct security_mnt_opts *opts)
554 {
555         int rc = 0, i;
556         struct task_security_struct *tsec = current->security;
557         struct superblock_security_struct *sbsec = sb->s_security;
558         const char *name = sb->s_type->name;
559         struct inode *inode = sbsec->sb->s_root->d_inode;
560         struct inode_security_struct *root_isec = inode->i_security;
561         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
562         u32 defcontext_sid = 0;
563         char **mount_options = opts->mnt_opts;
564         int *flags = opts->mnt_opts_flags;
565         int num_opts = opts->num_mnt_opts;
566
567         mutex_lock(&sbsec->lock);
568
569         if (!ss_initialized) {
570                 if (!num_opts) {
571                         /* Defer initialization until selinux_complete_init,
572                            after the initial policy is loaded and the security
573                            server is ready to handle calls. */
574                         spin_lock(&sb_security_lock);
575                         if (list_empty(&sbsec->list))
576                                 list_add(&sbsec->list, &superblock_security_head);
577                         spin_unlock(&sb_security_lock);
578                         goto out;
579                 }
580                 rc = -EINVAL;
581                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
582                         "before the security server is initialized\n");
583                 goto out;
584         }
585
586         /*
587          * Binary mount data FS will come through this function twice.  Once
588          * from an explicit call and once from the generic calls from the vfs.
589          * Since the generic VFS calls will not contain any security mount data
590          * we need to skip the double mount verification.
591          *
592          * This does open a hole in which we will not notice if the first
593          * mount using this sb set explict options and a second mount using
594          * this sb does not set any security options.  (The first options
595          * will be used for both mounts)
596          */
597         if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
598             && (num_opts == 0))
599                 goto out;
600
601         /*
602          * parse the mount options, check if they are valid sids.
603          * also check if someone is trying to mount the same sb more
604          * than once with different security options.
605          */
606         for (i = 0; i < num_opts; i++) {
607                 u32 sid;
608                 rc = security_context_to_sid(mount_options[i],
609                                              strlen(mount_options[i]), &sid);
610                 if (rc) {
611                         printk(KERN_WARNING "SELinux: security_context_to_sid"
612                                "(%s) failed for (dev %s, type %s) errno=%d\n",
613                                mount_options[i], sb->s_id, name, rc);
614                         goto out;
615                 }
616                 switch (flags[i]) {
617                 case FSCONTEXT_MNT:
618                         fscontext_sid = sid;
619
620                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
621                                         fscontext_sid))
622                                 goto out_double_mount;
623
624                         sbsec->flags |= FSCONTEXT_MNT;
625                         break;
626                 case CONTEXT_MNT:
627                         context_sid = sid;
628
629                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
630                                         context_sid))
631                                 goto out_double_mount;
632
633                         sbsec->flags |= CONTEXT_MNT;
634                         break;
635                 case ROOTCONTEXT_MNT:
636                         rootcontext_sid = sid;
637
638                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
639                                         rootcontext_sid))
640                                 goto out_double_mount;
641
642                         sbsec->flags |= ROOTCONTEXT_MNT;
643
644                         break;
645                 case DEFCONTEXT_MNT:
646                         defcontext_sid = sid;
647
648                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
649                                         defcontext_sid))
650                                 goto out_double_mount;
651
652                         sbsec->flags |= DEFCONTEXT_MNT;
653
654                         break;
655                 default:
656                         rc = -EINVAL;
657                         goto out;
658                 }
659         }
660
661         if (sbsec->initialized) {
662                 /* previously mounted with options, but not on this attempt? */
663                 if (sbsec->flags && !num_opts)
664                         goto out_double_mount;
665                 rc = 0;
666                 goto out;
667         }
668
669         if (strcmp(sb->s_type->name, "proc") == 0)
670                 sbsec->proc = 1;
671
672         /* Determine the labeling behavior to use for this filesystem type. */
673         rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
674         if (rc) {
675                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
676                        __func__, sb->s_type->name, rc);
677                 goto out;
678         }
679
680         /* sets the context of the superblock for the fs being mounted. */
681         if (fscontext_sid) {
682
683                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec);
684                 if (rc)
685                         goto out;
686
687                 sbsec->sid = fscontext_sid;
688         }
689
690         /*
691          * Switch to using mount point labeling behavior.
692          * sets the label used on all file below the mountpoint, and will set
693          * the superblock context if not already set.
694          */
695         if (context_sid) {
696                 if (!fscontext_sid) {
697                         rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec);
698                         if (rc)
699                                 goto out;
700                         sbsec->sid = context_sid;
701                 } else {
702                         rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec);
703                         if (rc)
704                                 goto out;
705                 }
706                 if (!rootcontext_sid)
707                         rootcontext_sid = context_sid;
708
709                 sbsec->mntpoint_sid = context_sid;
710                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
711         }
712
713         if (rootcontext_sid) {
714                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec);
715                 if (rc)
716                         goto out;
717
718                 root_isec->sid = rootcontext_sid;
719                 root_isec->initialized = 1;
720         }
721
722         if (defcontext_sid) {
723                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
724                         rc = -EINVAL;
725                         printk(KERN_WARNING "SELinux: defcontext option is "
726                                "invalid for this filesystem type\n");
727                         goto out;
728                 }
729
730                 if (defcontext_sid != sbsec->def_sid) {
731                         rc = may_context_mount_inode_relabel(defcontext_sid,
732                                                              sbsec, tsec);
733                         if (rc)
734                                 goto out;
735                 }
736
737                 sbsec->def_sid = defcontext_sid;
738         }
739
740         rc = sb_finish_set_opts(sb);
741 out:
742         mutex_unlock(&sbsec->lock);
743         return rc;
744 out_double_mount:
745         rc = -EINVAL;
746         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
747                "security settings for (dev %s, type %s)\n", sb->s_id, name);
748         goto out;
749 }
750
751 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
752                                         struct super_block *newsb)
753 {
754         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
755         struct superblock_security_struct *newsbsec = newsb->s_security;
756
757         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
758         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
759         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
760
761         /*
762          * if the parent was able to be mounted it clearly had no special lsm
763          * mount options.  thus we can safely put this sb on the list and deal
764          * with it later
765          */
766         if (!ss_initialized) {
767                 spin_lock(&sb_security_lock);
768                 if (list_empty(&newsbsec->list))
769                         list_add(&newsbsec->list, &superblock_security_head);
770                 spin_unlock(&sb_security_lock);
771                 return;
772         }
773
774         /* how can we clone if the old one wasn't set up?? */
775         BUG_ON(!oldsbsec->initialized);
776
777         /* if fs is reusing a sb, just let its options stand... */
778         if (newsbsec->initialized)
779                 return;
780
781         mutex_lock(&newsbsec->lock);
782
783         newsbsec->flags = oldsbsec->flags;
784
785         newsbsec->sid = oldsbsec->sid;
786         newsbsec->def_sid = oldsbsec->def_sid;
787         newsbsec->behavior = oldsbsec->behavior;
788
789         if (set_context) {
790                 u32 sid = oldsbsec->mntpoint_sid;
791
792                 if (!set_fscontext)
793                         newsbsec->sid = sid;
794                 if (!set_rootcontext) {
795                         struct inode *newinode = newsb->s_root->d_inode;
796                         struct inode_security_struct *newisec = newinode->i_security;
797                         newisec->sid = sid;
798                 }
799                 newsbsec->mntpoint_sid = sid;
800         }
801         if (set_rootcontext) {
802                 const struct inode *oldinode = oldsb->s_root->d_inode;
803                 const struct inode_security_struct *oldisec = oldinode->i_security;
804                 struct inode *newinode = newsb->s_root->d_inode;
805                 struct inode_security_struct *newisec = newinode->i_security;
806
807                 newisec->sid = oldisec->sid;
808         }
809
810         sb_finish_set_opts(newsb);
811         mutex_unlock(&newsbsec->lock);
812 }
813
814 static int selinux_parse_opts_str(char *options,
815                                   struct security_mnt_opts *opts)
816 {
817         char *p;
818         char *context = NULL, *defcontext = NULL;
819         char *fscontext = NULL, *rootcontext = NULL;
820         int rc, num_mnt_opts = 0;
821
822         opts->num_mnt_opts = 0;
823
824         /* Standard string-based options. */
825         while ((p = strsep(&options, "|")) != NULL) {
826                 int token;
827                 substring_t args[MAX_OPT_ARGS];
828
829                 if (!*p)
830                         continue;
831
832                 token = match_token(p, tokens, args);
833
834                 switch (token) {
835                 case Opt_context:
836                         if (context || defcontext) {
837                                 rc = -EINVAL;
838                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
839                                 goto out_err;
840                         }
841                         context = match_strdup(&args[0]);
842                         if (!context) {
843                                 rc = -ENOMEM;
844                                 goto out_err;
845                         }
846                         break;
847
848                 case Opt_fscontext:
849                         if (fscontext) {
850                                 rc = -EINVAL;
851                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
852                                 goto out_err;
853                         }
854                         fscontext = match_strdup(&args[0]);
855                         if (!fscontext) {
856                                 rc = -ENOMEM;
857                                 goto out_err;
858                         }
859                         break;
860
861                 case Opt_rootcontext:
862                         if (rootcontext) {
863                                 rc = -EINVAL;
864                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
865                                 goto out_err;
866                         }
867                         rootcontext = match_strdup(&args[0]);
868                         if (!rootcontext) {
869                                 rc = -ENOMEM;
870                                 goto out_err;
871                         }
872                         break;
873
874                 case Opt_defcontext:
875                         if (context || defcontext) {
876                                 rc = -EINVAL;
877                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
878                                 goto out_err;
879                         }
880                         defcontext = match_strdup(&args[0]);
881                         if (!defcontext) {
882                                 rc = -ENOMEM;
883                                 goto out_err;
884                         }
885                         break;
886
887                 default:
888                         rc = -EINVAL;
889                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
890                         goto out_err;
891
892                 }
893         }
894
895         rc = -ENOMEM;
896         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
897         if (!opts->mnt_opts)
898                 goto out_err;
899
900         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
901         if (!opts->mnt_opts_flags) {
902                 kfree(opts->mnt_opts);
903                 goto out_err;
904         }
905
906         if (fscontext) {
907                 opts->mnt_opts[num_mnt_opts] = fscontext;
908                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
909         }
910         if (context) {
911                 opts->mnt_opts[num_mnt_opts] = context;
912                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
913         }
914         if (rootcontext) {
915                 opts->mnt_opts[num_mnt_opts] = rootcontext;
916                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
917         }
918         if (defcontext) {
919                 opts->mnt_opts[num_mnt_opts] = defcontext;
920                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
921         }
922
923         opts->num_mnt_opts = num_mnt_opts;
924         return 0;
925
926 out_err:
927         kfree(context);
928         kfree(defcontext);
929         kfree(fscontext);
930         kfree(rootcontext);
931         return rc;
932 }
933 /*
934  * string mount options parsing and call set the sbsec
935  */
936 static int superblock_doinit(struct super_block *sb, void *data)
937 {
938         int rc = 0;
939         char *options = data;
940         struct security_mnt_opts opts;
941
942         security_init_mnt_opts(&opts);
943
944         if (!data)
945                 goto out;
946
947         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
948
949         rc = selinux_parse_opts_str(options, &opts);
950         if (rc)
951                 goto out_err;
952
953 out:
954         rc = selinux_set_mnt_opts(sb, &opts);
955
956 out_err:
957         security_free_mnt_opts(&opts);
958         return rc;
959 }
960
961 void selinux_write_opts(struct seq_file *m, 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 = strchr(opts->mnt_opts[i], ',');
968
969                 switch (opts->mnt_opts_flags[i]) {
970                 case CONTEXT_MNT:
971                         prefix = CONTEXT_STR;
972                         break;
973                 case FSCONTEXT_MNT:
974                         prefix = FSCONTEXT_STR;
975                         break;
976                 case ROOTCONTEXT_MNT:
977                         prefix = ROOTCONTEXT_STR;
978                         break;
979                 case DEFCONTEXT_MNT:
980                         prefix = DEFCONTEXT_STR;
981                         break;
982                 default:
983                         BUG();
984                 };
985                 /* we need a comma before each option */
986                 seq_putc(m, ',');
987                 seq_puts(m, prefix);
988                 if (has_comma)
989                         seq_putc(m, '\"');
990                 seq_puts(m, opts->mnt_opts[i]);
991                 if (has_comma)
992                         seq_putc(m, '\"');
993         }
994 }
995
996 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
997 {
998         struct security_mnt_opts opts;
999         int rc;
1000
1001         rc = selinux_get_mnt_opts(sb, &opts);
1002         if (rc) {
1003                 /* before policy load we may get EINVAL, don't show anything */
1004                 if (rc == -EINVAL)
1005                         rc = 0;
1006                 return rc;
1007         }
1008
1009         selinux_write_opts(m, &opts);
1010
1011         security_free_mnt_opts(&opts);
1012
1013         return rc;
1014 }
1015
1016 static inline u16 inode_mode_to_security_class(umode_t mode)
1017 {
1018         switch (mode & S_IFMT) {
1019         case S_IFSOCK:
1020                 return SECCLASS_SOCK_FILE;
1021         case S_IFLNK:
1022                 return SECCLASS_LNK_FILE;
1023         case S_IFREG:
1024                 return SECCLASS_FILE;
1025         case S_IFBLK:
1026                 return SECCLASS_BLK_FILE;
1027         case S_IFDIR:
1028                 return SECCLASS_DIR;
1029         case S_IFCHR:
1030                 return SECCLASS_CHR_FILE;
1031         case S_IFIFO:
1032                 return SECCLASS_FIFO_FILE;
1033
1034         }
1035
1036         return SECCLASS_FILE;
1037 }
1038
1039 static inline int default_protocol_stream(int protocol)
1040 {
1041         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1042 }
1043
1044 static inline int default_protocol_dgram(int protocol)
1045 {
1046         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1047 }
1048
1049 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1050 {
1051         switch (family) {
1052         case PF_UNIX:
1053                 switch (type) {
1054                 case SOCK_STREAM:
1055                 case SOCK_SEQPACKET:
1056                         return SECCLASS_UNIX_STREAM_SOCKET;
1057                 case SOCK_DGRAM:
1058                         return SECCLASS_UNIX_DGRAM_SOCKET;
1059                 }
1060                 break;
1061         case PF_INET:
1062         case PF_INET6:
1063                 switch (type) {
1064                 case SOCK_STREAM:
1065                         if (default_protocol_stream(protocol))
1066                                 return SECCLASS_TCP_SOCKET;
1067                         else
1068                                 return SECCLASS_RAWIP_SOCKET;
1069                 case SOCK_DGRAM:
1070                         if (default_protocol_dgram(protocol))
1071                                 return SECCLASS_UDP_SOCKET;
1072                         else
1073                                 return SECCLASS_RAWIP_SOCKET;
1074                 case SOCK_DCCP:
1075                         return SECCLASS_DCCP_SOCKET;
1076                 default:
1077                         return SECCLASS_RAWIP_SOCKET;
1078                 }
1079                 break;
1080         case PF_NETLINK:
1081                 switch (protocol) {
1082                 case NETLINK_ROUTE:
1083                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1084                 case NETLINK_FIREWALL:
1085                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1086                 case NETLINK_INET_DIAG:
1087                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1088                 case NETLINK_NFLOG:
1089                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1090                 case NETLINK_XFRM:
1091                         return SECCLASS_NETLINK_XFRM_SOCKET;
1092                 case NETLINK_SELINUX:
1093                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1094                 case NETLINK_AUDIT:
1095                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1096                 case NETLINK_IP6_FW:
1097                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1098                 case NETLINK_DNRTMSG:
1099                         return SECCLASS_NETLINK_DNRT_SOCKET;
1100                 case NETLINK_KOBJECT_UEVENT:
1101                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1102                 default:
1103                         return SECCLASS_NETLINK_SOCKET;
1104                 }
1105         case PF_PACKET:
1106                 return SECCLASS_PACKET_SOCKET;
1107         case PF_KEY:
1108                 return SECCLASS_KEY_SOCKET;
1109         case PF_APPLETALK:
1110                 return SECCLASS_APPLETALK_SOCKET;
1111         }
1112
1113         return SECCLASS_SOCKET;
1114 }
1115
1116 #ifdef CONFIG_PROC_FS
1117 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1118                                 u16 tclass,
1119                                 u32 *sid)
1120 {
1121         int buflen, rc;
1122         char *buffer, *path, *end;
1123
1124         buffer = (char *)__get_free_page(GFP_KERNEL);
1125         if (!buffer)
1126                 return -ENOMEM;
1127
1128         buflen = PAGE_SIZE;
1129         end = buffer+buflen;
1130         *--end = '\0';
1131         buflen--;
1132         path = end-1;
1133         *path = '/';
1134         while (de && de != de->parent) {
1135                 buflen -= de->namelen + 1;
1136                 if (buflen < 0)
1137                         break;
1138                 end -= de->namelen;
1139                 memcpy(end, de->name, de->namelen);
1140                 *--end = '/';
1141                 path = end;
1142                 de = de->parent;
1143         }
1144         rc = security_genfs_sid("proc", path, tclass, sid);
1145         free_page((unsigned long)buffer);
1146         return rc;
1147 }
1148 #else
1149 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1150                                 u16 tclass,
1151                                 u32 *sid)
1152 {
1153         return -EINVAL;
1154 }
1155 #endif
1156
1157 /* The inode's security attributes must be initialized before first use. */
1158 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1159 {
1160         struct superblock_security_struct *sbsec = NULL;
1161         struct inode_security_struct *isec = inode->i_security;
1162         u32 sid;
1163         struct dentry *dentry;
1164 #define INITCONTEXTLEN 255
1165         char *context = NULL;
1166         unsigned len = 0;
1167         int rc = 0;
1168
1169         if (isec->initialized)
1170                 goto out;
1171
1172         mutex_lock(&isec->lock);
1173         if (isec->initialized)
1174                 goto out_unlock;
1175
1176         sbsec = inode->i_sb->s_security;
1177         if (!sbsec->initialized) {
1178                 /* Defer initialization until selinux_complete_init,
1179                    after the initial policy is loaded and the security
1180                    server is ready to handle calls. */
1181                 spin_lock(&sbsec->isec_lock);
1182                 if (list_empty(&isec->list))
1183                         list_add(&isec->list, &sbsec->isec_head);
1184                 spin_unlock(&sbsec->isec_lock);
1185                 goto out_unlock;
1186         }
1187
1188         switch (sbsec->behavior) {
1189         case SECURITY_FS_USE_XATTR:
1190                 if (!inode->i_op->getxattr) {
1191                         isec->sid = sbsec->def_sid;
1192                         break;
1193                 }
1194
1195                 /* Need a dentry, since the xattr API requires one.
1196                    Life would be simpler if we could just pass the inode. */
1197                 if (opt_dentry) {
1198                         /* Called from d_instantiate or d_splice_alias. */
1199                         dentry = dget(opt_dentry);
1200                 } else {
1201                         /* Called from selinux_complete_init, try to find a dentry. */
1202                         dentry = d_find_alias(inode);
1203                 }
1204                 if (!dentry) {
1205                         printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1206                                "ino=%ld\n", __func__, inode->i_sb->s_id,
1207                                inode->i_ino);
1208                         goto out_unlock;
1209                 }
1210
1211                 len = INITCONTEXTLEN;
1212                 context = kmalloc(len, GFP_NOFS);
1213                 if (!context) {
1214                         rc = -ENOMEM;
1215                         dput(dentry);
1216                         goto out_unlock;
1217                 }
1218                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1219                                            context, len);
1220                 if (rc == -ERANGE) {
1221                         /* Need a larger buffer.  Query for the right size. */
1222                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1223                                                    NULL, 0);
1224                         if (rc < 0) {
1225                                 dput(dentry);
1226                                 goto out_unlock;
1227                         }
1228                         kfree(context);
1229                         len = rc;
1230                         context = kmalloc(len, GFP_NOFS);
1231                         if (!context) {
1232                                 rc = -ENOMEM;
1233                                 dput(dentry);
1234                                 goto out_unlock;
1235                         }
1236                         rc = inode->i_op->getxattr(dentry,
1237                                                    XATTR_NAME_SELINUX,
1238                                                    context, len);
1239                 }
1240                 dput(dentry);
1241                 if (rc < 0) {
1242                         if (rc != -ENODATA) {
1243                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1244                                        "%d for dev=%s ino=%ld\n", __func__,
1245                                        -rc, inode->i_sb->s_id, inode->i_ino);
1246                                 kfree(context);
1247                                 goto out_unlock;
1248                         }
1249                         /* Map ENODATA to the default file SID */
1250                         sid = sbsec->def_sid;
1251                         rc = 0;
1252                 } else {
1253                         rc = security_context_to_sid_default(context, rc, &sid,
1254                                                              sbsec->def_sid,
1255                                                              GFP_NOFS);
1256                         if (rc) {
1257                                 printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1258                                        "returned %d for dev=%s ino=%ld\n",
1259                                        __func__, context, -rc,
1260                                        inode->i_sb->s_id, inode->i_ino);
1261                                 kfree(context);
1262                                 /* Leave with the unlabeled SID */
1263                                 rc = 0;
1264                                 break;
1265                         }
1266                 }
1267                 kfree(context);
1268                 isec->sid = sid;
1269                 break;
1270         case SECURITY_FS_USE_TASK:
1271                 isec->sid = isec->task_sid;
1272                 break;
1273         case SECURITY_FS_USE_TRANS:
1274                 /* Default to the fs SID. */
1275                 isec->sid = sbsec->sid;
1276
1277                 /* Try to obtain a transition SID. */
1278                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1279                 rc = security_transition_sid(isec->task_sid,
1280                                              sbsec->sid,
1281                                              isec->sclass,
1282                                              &sid);
1283                 if (rc)
1284                         goto out_unlock;
1285                 isec->sid = sid;
1286                 break;
1287         case SECURITY_FS_USE_MNTPOINT:
1288                 isec->sid = sbsec->mntpoint_sid;
1289                 break;
1290         default:
1291                 /* Default to the fs superblock SID. */
1292                 isec->sid = sbsec->sid;
1293
1294                 if (sbsec->proc) {
1295                         struct proc_inode *proci = PROC_I(inode);
1296                         if (proci->pde) {
1297                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1298                                 rc = selinux_proc_get_sid(proci->pde,
1299                                                           isec->sclass,
1300                                                           &sid);
1301                                 if (rc)
1302                                         goto out_unlock;
1303                                 isec->sid = sid;
1304                         }
1305                 }
1306                 break;
1307         }
1308
1309         isec->initialized = 1;
1310
1311 out_unlock:
1312         mutex_unlock(&isec->lock);
1313 out:
1314         if (isec->sclass == SECCLASS_FILE)
1315                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1316         return rc;
1317 }
1318
1319 /* Convert a Linux signal to an access vector. */
1320 static inline u32 signal_to_av(int sig)
1321 {
1322         u32 perm = 0;
1323
1324         switch (sig) {
1325         case SIGCHLD:
1326                 /* Commonly granted from child to parent. */
1327                 perm = PROCESS__SIGCHLD;
1328                 break;
1329         case SIGKILL:
1330                 /* Cannot be caught or ignored */
1331                 perm = PROCESS__SIGKILL;
1332                 break;
1333         case SIGSTOP:
1334                 /* Cannot be caught or ignored */
1335                 perm = PROCESS__SIGSTOP;
1336                 break;
1337         default:
1338                 /* All other signals. */
1339                 perm = PROCESS__SIGNAL;
1340                 break;
1341         }
1342
1343         return perm;
1344 }
1345
1346 /* Check permission betweeen a pair of tasks, e.g. signal checks,
1347    fork check, ptrace check, etc. */
1348 static int task_has_perm(struct task_struct *tsk1,
1349                          struct task_struct *tsk2,
1350                          u32 perms)
1351 {
1352         struct task_security_struct *tsec1, *tsec2;
1353
1354         tsec1 = tsk1->security;
1355         tsec2 = tsk2->security;
1356         return avc_has_perm(tsec1->sid, tsec2->sid,
1357                             SECCLASS_PROCESS, perms, NULL);
1358 }
1359
1360 #if CAP_LAST_CAP > 63
1361 #error Fix SELinux to handle capabilities > 63.
1362 #endif
1363
1364 /* Check whether a task is allowed to use a capability. */
1365 static int task_has_capability(struct task_struct *tsk,
1366                                int cap)
1367 {
1368         struct task_security_struct *tsec;
1369         struct avc_audit_data ad;
1370         u16 sclass;
1371         u32 av = CAP_TO_MASK(cap);
1372
1373         tsec = tsk->security;
1374
1375         AVC_AUDIT_DATA_INIT(&ad, CAP);
1376         ad.tsk = tsk;
1377         ad.u.cap = cap;
1378
1379         switch (CAP_TO_INDEX(cap)) {
1380         case 0:
1381                 sclass = SECCLASS_CAPABILITY;
1382                 break;
1383         case 1:
1384                 sclass = SECCLASS_CAPABILITY2;
1385                 break;
1386         default:
1387                 printk(KERN_ERR
1388                        "SELinux:  out of range capability %d\n", cap);
1389                 BUG();
1390         }
1391         return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad);
1392 }
1393
1394 /* Check whether a task is allowed to use a system operation. */
1395 static int task_has_system(struct task_struct *tsk,
1396                            u32 perms)
1397 {
1398         struct task_security_struct *tsec;
1399
1400         tsec = tsk->security;
1401
1402         return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1403                             SECCLASS_SYSTEM, perms, NULL);
1404 }
1405
1406 /* Check whether a task has a particular permission to an inode.
1407    The 'adp' parameter is optional and allows other audit
1408    data to be passed (e.g. the dentry). */
1409 static int inode_has_perm(struct task_struct *tsk,
1410                           struct inode *inode,
1411                           u32 perms,
1412                           struct avc_audit_data *adp)
1413 {
1414         struct task_security_struct *tsec;
1415         struct inode_security_struct *isec;
1416         struct avc_audit_data ad;
1417
1418         if (unlikely(IS_PRIVATE(inode)))
1419                 return 0;
1420
1421         tsec = tsk->security;
1422         isec = inode->i_security;
1423
1424         if (!adp) {
1425                 adp = &ad;
1426                 AVC_AUDIT_DATA_INIT(&ad, FS);
1427                 ad.u.fs.inode = inode;
1428         }
1429
1430         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1431 }
1432
1433 /* Same as inode_has_perm, but pass explicit audit data containing
1434    the dentry to help the auditing code to more easily generate the
1435    pathname if needed. */
1436 static inline int dentry_has_perm(struct task_struct *tsk,
1437                                   struct vfsmount *mnt,
1438                                   struct dentry *dentry,
1439                                   u32 av)
1440 {
1441         struct inode *inode = dentry->d_inode;
1442         struct avc_audit_data ad;
1443         AVC_AUDIT_DATA_INIT(&ad, FS);
1444         ad.u.fs.path.mnt = mnt;
1445         ad.u.fs.path.dentry = dentry;
1446         return inode_has_perm(tsk, inode, av, &ad);
1447 }
1448
1449 /* Check whether a task can use an open file descriptor to
1450    access an inode in a given way.  Check access to the
1451    descriptor itself, and then use dentry_has_perm to
1452    check a particular permission to the file.
1453    Access to the descriptor is implicitly granted if it
1454    has the same SID as the process.  If av is zero, then
1455    access to the file is not checked, e.g. for cases
1456    where only the descriptor is affected like seek. */
1457 static int file_has_perm(struct task_struct *tsk,
1458                                 struct file *file,
1459                                 u32 av)
1460 {
1461         struct task_security_struct *tsec = tsk->security;
1462         struct file_security_struct *fsec = file->f_security;
1463         struct inode *inode = file->f_path.dentry->d_inode;
1464         struct avc_audit_data ad;
1465         int rc;
1466
1467         AVC_AUDIT_DATA_INIT(&ad, FS);
1468         ad.u.fs.path = file->f_path;
1469
1470         if (tsec->sid != fsec->sid) {
1471                 rc = avc_has_perm(tsec->sid, fsec->sid,
1472                                   SECCLASS_FD,
1473                                   FD__USE,
1474                                   &ad);
1475                 if (rc)
1476                         return rc;
1477         }
1478
1479         /* av is zero if only checking access to the descriptor. */
1480         if (av)
1481                 return inode_has_perm(tsk, inode, av, &ad);
1482
1483         return 0;
1484 }
1485
1486 /* Check whether a task can create a file. */
1487 static int may_create(struct inode *dir,
1488                       struct dentry *dentry,
1489                       u16 tclass)
1490 {
1491         struct task_security_struct *tsec;
1492         struct inode_security_struct *dsec;
1493         struct superblock_security_struct *sbsec;
1494         u32 newsid;
1495         struct avc_audit_data ad;
1496         int rc;
1497
1498         tsec = current->security;
1499         dsec = dir->i_security;
1500         sbsec = dir->i_sb->s_security;
1501
1502         AVC_AUDIT_DATA_INIT(&ad, FS);
1503         ad.u.fs.path.dentry = dentry;
1504
1505         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1506                           DIR__ADD_NAME | DIR__SEARCH,
1507                           &ad);
1508         if (rc)
1509                 return rc;
1510
1511         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1512                 newsid = tsec->create_sid;
1513         } else {
1514                 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1515                                              &newsid);
1516                 if (rc)
1517                         return rc;
1518         }
1519
1520         rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1521         if (rc)
1522                 return rc;
1523
1524         return avc_has_perm(newsid, sbsec->sid,
1525                             SECCLASS_FILESYSTEM,
1526                             FILESYSTEM__ASSOCIATE, &ad);
1527 }
1528
1529 /* Check whether a task can create a key. */
1530 static int may_create_key(u32 ksid,
1531                           struct task_struct *ctx)
1532 {
1533         struct task_security_struct *tsec;
1534
1535         tsec = ctx->security;
1536
1537         return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1538 }
1539
1540 #define MAY_LINK        0
1541 #define MAY_UNLINK      1
1542 #define MAY_RMDIR       2
1543
1544 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1545 static int may_link(struct inode *dir,
1546                     struct dentry *dentry,
1547                     int kind)
1548
1549 {
1550         struct task_security_struct *tsec;
1551         struct inode_security_struct *dsec, *isec;
1552         struct avc_audit_data ad;
1553         u32 av;
1554         int rc;
1555
1556         tsec = current->security;
1557         dsec = dir->i_security;
1558         isec = dentry->d_inode->i_security;
1559
1560         AVC_AUDIT_DATA_INIT(&ad, FS);
1561         ad.u.fs.path.dentry = dentry;
1562
1563         av = DIR__SEARCH;
1564         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1565         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1566         if (rc)
1567                 return rc;
1568
1569         switch (kind) {
1570         case MAY_LINK:
1571                 av = FILE__LINK;
1572                 break;
1573         case MAY_UNLINK:
1574                 av = FILE__UNLINK;
1575                 break;
1576         case MAY_RMDIR:
1577                 av = DIR__RMDIR;
1578                 break;
1579         default:
1580                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1581                         __func__, kind);
1582                 return 0;
1583         }
1584
1585         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1586         return rc;
1587 }
1588
1589 static inline int may_rename(struct inode *old_dir,
1590                              struct dentry *old_dentry,
1591                              struct inode *new_dir,
1592                              struct dentry *new_dentry)
1593 {
1594         struct task_security_struct *tsec;
1595         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1596         struct avc_audit_data ad;
1597         u32 av;
1598         int old_is_dir, new_is_dir;
1599         int rc;
1600
1601         tsec = current->security;
1602         old_dsec = old_dir->i_security;
1603         old_isec = old_dentry->d_inode->i_security;
1604         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1605         new_dsec = new_dir->i_security;
1606
1607         AVC_AUDIT_DATA_INIT(&ad, FS);
1608
1609         ad.u.fs.path.dentry = old_dentry;
1610         rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1611                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1612         if (rc)
1613                 return rc;
1614         rc = avc_has_perm(tsec->sid, old_isec->sid,
1615                           old_isec->sclass, FILE__RENAME, &ad);
1616         if (rc)
1617                 return rc;
1618         if (old_is_dir && new_dir != old_dir) {
1619                 rc = avc_has_perm(tsec->sid, old_isec->sid,
1620                                   old_isec->sclass, DIR__REPARENT, &ad);
1621                 if (rc)
1622                         return rc;
1623         }
1624
1625         ad.u.fs.path.dentry = new_dentry;
1626         av = DIR__ADD_NAME | DIR__SEARCH;
1627         if (new_dentry->d_inode)
1628                 av |= DIR__REMOVE_NAME;
1629         rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1630         if (rc)
1631                 return rc;
1632         if (new_dentry->d_inode) {
1633                 new_isec = new_dentry->d_inode->i_security;
1634                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1635                 rc = avc_has_perm(tsec->sid, new_isec->sid,
1636                                   new_isec->sclass,
1637                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1638                 if (rc)
1639                         return rc;
1640         }
1641
1642         return 0;
1643 }
1644
1645 /* Check whether a task can perform a filesystem operation. */
1646 static int superblock_has_perm(struct task_struct *tsk,
1647                                struct super_block *sb,
1648                                u32 perms,
1649                                struct avc_audit_data *ad)
1650 {
1651         struct task_security_struct *tsec;
1652         struct superblock_security_struct *sbsec;
1653
1654         tsec = tsk->security;
1655         sbsec = sb->s_security;
1656         return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1657                             perms, ad);
1658 }
1659
1660 /* Convert a Linux mode and permission mask to an access vector. */
1661 static inline u32 file_mask_to_av(int mode, int mask)
1662 {
1663         u32 av = 0;
1664
1665         if ((mode & S_IFMT) != S_IFDIR) {
1666                 if (mask & MAY_EXEC)
1667                         av |= FILE__EXECUTE;
1668                 if (mask & MAY_READ)
1669                         av |= FILE__READ;
1670
1671                 if (mask & MAY_APPEND)
1672                         av |= FILE__APPEND;
1673                 else if (mask & MAY_WRITE)
1674                         av |= FILE__WRITE;
1675
1676         } else {
1677                 if (mask & MAY_EXEC)
1678                         av |= DIR__SEARCH;
1679                 if (mask & MAY_WRITE)
1680                         av |= DIR__WRITE;
1681                 if (mask & MAY_READ)
1682                         av |= DIR__READ;
1683         }
1684
1685         return av;
1686 }
1687
1688 /*
1689  * Convert a file mask to an access vector and include the correct open
1690  * open permission.
1691  */
1692 static inline u32 open_file_mask_to_av(int mode, int mask)
1693 {
1694         u32 av = file_mask_to_av(mode, mask);
1695
1696         if (selinux_policycap_openperm) {
1697                 /*
1698                  * lnk files and socks do not really have an 'open'
1699                  */
1700                 if (S_ISREG(mode))
1701                         av |= FILE__OPEN;
1702                 else if (S_ISCHR(mode))
1703                         av |= CHR_FILE__OPEN;
1704                 else if (S_ISBLK(mode))
1705                         av |= BLK_FILE__OPEN;
1706                 else if (S_ISFIFO(mode))
1707                         av |= FIFO_FILE__OPEN;
1708                 else if (S_ISDIR(mode))
1709                         av |= DIR__OPEN;
1710                 else
1711                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1712                                 "unknown mode:%x\n", __func__, mode);
1713         }
1714         return av;
1715 }
1716
1717 /* Convert a Linux file to an access vector. */
1718 static inline u32 file_to_av(struct file *file)
1719 {
1720         u32 av = 0;
1721
1722         if (file->f_mode & FMODE_READ)
1723                 av |= FILE__READ;
1724         if (file->f_mode & FMODE_WRITE) {
1725                 if (file->f_flags & O_APPEND)
1726                         av |= FILE__APPEND;
1727                 else
1728                         av |= FILE__WRITE;
1729         }
1730         if (!av) {
1731                 /*
1732                  * Special file opened with flags 3 for ioctl-only use.
1733                  */
1734                 av = FILE__IOCTL;
1735         }
1736
1737         return av;
1738 }
1739
1740 /* Hook functions begin here. */
1741
1742 static int selinux_ptrace_may_access(struct task_struct *child,
1743                                      unsigned int mode)
1744 {
1745         int rc;
1746
1747         rc = secondary_ops->ptrace_may_access(child, mode);
1748         if (rc)
1749                 return rc;
1750
1751         if (mode == PTRACE_MODE_READ) {
1752                 struct task_security_struct *tsec = current->security;
1753                 struct task_security_struct *csec = child->security;
1754                 return avc_has_perm(tsec->sid, csec->sid,
1755                                     SECCLASS_FILE, FILE__READ, NULL);
1756         }
1757
1758         return task_has_perm(current, child, PROCESS__PTRACE);
1759 }
1760
1761 static int selinux_ptrace_traceme(struct task_struct *parent)
1762 {
1763         int rc;
1764
1765         rc = secondary_ops->ptrace_traceme(parent);
1766         if (rc)
1767                 return rc;
1768
1769         return task_has_perm(parent, current, PROCESS__PTRACE);
1770 }
1771
1772 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1773                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1774 {
1775         int error;
1776
1777         error = task_has_perm(current, target, PROCESS__GETCAP);
1778         if (error)
1779                 return error;
1780
1781         return secondary_ops->capget(target, effective, inheritable, permitted);
1782 }
1783
1784 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1785                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1786 {
1787         int error;
1788
1789         error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1790         if (error)
1791                 return error;
1792
1793         return task_has_perm(current, target, PROCESS__SETCAP);
1794 }
1795
1796 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1797                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1798 {
1799         secondary_ops->capset_set(target, effective, inheritable, permitted);
1800 }
1801
1802 static int selinux_capable(struct task_struct *tsk, int cap)
1803 {
1804         int rc;
1805
1806         rc = secondary_ops->capable(tsk, cap);
1807         if (rc)
1808                 return rc;
1809
1810         return task_has_capability(tsk, cap);
1811 }
1812
1813 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1814 {
1815         int buflen, rc;
1816         char *buffer, *path, *end;
1817
1818         rc = -ENOMEM;
1819         buffer = (char *)__get_free_page(GFP_KERNEL);
1820         if (!buffer)
1821                 goto out;
1822
1823         buflen = PAGE_SIZE;
1824         end = buffer+buflen;
1825         *--end = '\0';
1826         buflen--;
1827         path = end-1;
1828         *path = '/';
1829         while (table) {
1830                 const char *name = table->procname;
1831                 size_t namelen = strlen(name);
1832                 buflen -= namelen + 1;
1833                 if (buflen < 0)
1834                         goto out_free;
1835                 end -= namelen;
1836                 memcpy(end, name, namelen);
1837                 *--end = '/';
1838                 path = end;
1839                 table = table->parent;
1840         }
1841         buflen -= 4;
1842         if (buflen < 0)
1843                 goto out_free;
1844         end -= 4;
1845         memcpy(end, "/sys", 4);
1846         path = end;
1847         rc = security_genfs_sid("proc", path, tclass, sid);
1848 out_free:
1849         free_page((unsigned long)buffer);
1850 out:
1851         return rc;
1852 }
1853
1854 static int selinux_sysctl(ctl_table *table, int op)
1855 {
1856         int error = 0;
1857         u32 av;
1858         struct task_security_struct *tsec;
1859         u32 tsid;
1860         int rc;
1861
1862         rc = secondary_ops->sysctl(table, op);
1863         if (rc)
1864                 return rc;
1865
1866         tsec = current->security;
1867
1868         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1869                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1870         if (rc) {
1871                 /* Default to the well-defined sysctl SID. */
1872                 tsid = SECINITSID_SYSCTL;
1873         }
1874
1875         /* The op values are "defined" in sysctl.c, thereby creating
1876          * a bad coupling between this module and sysctl.c */
1877         if (op == 001) {
1878                 error = avc_has_perm(tsec->sid, tsid,
1879                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1880         } else {
1881                 av = 0;
1882                 if (op & 004)
1883                         av |= FILE__READ;
1884                 if (op & 002)
1885                         av |= FILE__WRITE;
1886                 if (av)
1887                         error = avc_has_perm(tsec->sid, tsid,
1888                                              SECCLASS_FILE, av, NULL);
1889         }
1890
1891         return error;
1892 }
1893
1894 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1895 {
1896         int rc = 0;
1897
1898         if (!sb)
1899                 return 0;
1900
1901         switch (cmds) {
1902         case Q_SYNC:
1903         case Q_QUOTAON:
1904         case Q_QUOTAOFF:
1905         case Q_SETINFO:
1906         case Q_SETQUOTA:
1907                 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD,
1908                                          NULL);
1909                 break;
1910         case Q_GETFMT:
1911         case Q_GETINFO:
1912         case Q_GETQUOTA:
1913                 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET,
1914                                          NULL);
1915                 break;
1916         default:
1917                 rc = 0;  /* let the kernel handle invalid cmds */
1918                 break;
1919         }
1920         return rc;
1921 }
1922
1923 static int selinux_quota_on(struct dentry *dentry)
1924 {
1925         return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1926 }
1927
1928 static int selinux_syslog(int type)
1929 {
1930         int rc;
1931
1932         rc = secondary_ops->syslog(type);
1933         if (rc)
1934                 return rc;
1935
1936         switch (type) {
1937         case 3:         /* Read last kernel messages */
1938         case 10:        /* Return size of the log buffer */
1939                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1940                 break;
1941         case 6:         /* Disable logging to console */
1942         case 7:         /* Enable logging to console */
1943         case 8:         /* Set level of messages printed to console */
1944                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1945                 break;
1946         case 0:         /* Close log */
1947         case 1:         /* Open log */
1948         case 2:         /* Read from log */
1949         case 4:         /* Read/clear last kernel messages */
1950         case 5:         /* Clear ring buffer */
1951         default:
1952                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1953                 break;
1954         }
1955         return rc;
1956 }
1957
1958 /*
1959  * Check that a process has enough memory to allocate a new virtual
1960  * mapping. 0 means there is enough memory for the allocation to
1961  * succeed and -ENOMEM implies there is not.
1962  *
1963  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1964  * if the capability is granted, but __vm_enough_memory requires 1 if
1965  * the capability is granted.
1966  *
1967  * Do not audit the selinux permission check, as this is applied to all
1968  * processes that allocate mappings.
1969  */
1970 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1971 {
1972         int rc, cap_sys_admin = 0;
1973         struct task_security_struct *tsec = current->security;
1974
1975         rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1976         if (rc == 0)
1977                 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1978                                           SECCLASS_CAPABILITY,
1979                                           CAP_TO_MASK(CAP_SYS_ADMIN),
1980                                           0,
1981                                           NULL);
1982
1983         if (rc == 0)
1984                 cap_sys_admin = 1;
1985
1986         return __vm_enough_memory(mm, pages, cap_sys_admin);
1987 }
1988
1989 /* binprm security operations */
1990
1991 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1992 {
1993         struct bprm_security_struct *bsec;
1994
1995         bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1996         if (!bsec)
1997                 return -ENOMEM;
1998
1999         bsec->sid = SECINITSID_UNLABELED;
2000         bsec->set = 0;
2001
2002         bprm->security = bsec;
2003         return 0;
2004 }
2005
2006 static int selinux_bprm_set_security(struct linux_binprm *bprm)
2007 {
2008         struct task_security_struct *tsec;
2009         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2010         struct inode_security_struct *isec;
2011         struct bprm_security_struct *bsec;
2012         u32 newsid;
2013         struct avc_audit_data ad;
2014         int rc;
2015
2016         rc = secondary_ops->bprm_set_security(bprm);
2017         if (rc)
2018                 return rc;
2019
2020         bsec = bprm->security;
2021
2022         if (bsec->set)
2023                 return 0;
2024
2025         tsec = current->security;
2026         isec = inode->i_security;
2027
2028         /* Default to the current task SID. */
2029         bsec->sid = tsec->sid;
2030
2031         /* Reset fs, key, and sock SIDs on execve. */
2032         tsec->create_sid = 0;
2033         tsec->keycreate_sid = 0;
2034         tsec->sockcreate_sid = 0;
2035
2036         if (tsec->exec_sid) {
2037                 newsid = tsec->exec_sid;
2038                 /* Reset exec SID on execve. */
2039                 tsec->exec_sid = 0;
2040         } else {
2041                 /* Check for a default transition on this program. */
2042                 rc = security_transition_sid(tsec->sid, isec->sid,
2043                                              SECCLASS_PROCESS, &newsid);
2044                 if (rc)
2045                         return rc;
2046         }
2047
2048         AVC_AUDIT_DATA_INIT(&ad, FS);
2049         ad.u.fs.path = bprm->file->f_path;
2050
2051         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2052                 newsid = tsec->sid;
2053
2054         if (tsec->sid == newsid) {
2055                 rc = avc_has_perm(tsec->sid, isec->sid,
2056                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2057                 if (rc)
2058                         return rc;
2059         } else {
2060                 /* Check permissions for the transition. */
2061                 rc = avc_has_perm(tsec->sid, newsid,
2062                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2063                 if (rc)
2064                         return rc;
2065
2066                 rc = avc_has_perm(newsid, isec->sid,
2067                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2068                 if (rc)
2069                         return rc;
2070
2071                 /* Clear any possibly unsafe personality bits on exec: */
2072                 current->personality &= ~PER_CLEAR_ON_SETID;
2073
2074                 /* Set the security field to the new SID. */
2075                 bsec->sid = newsid;
2076         }
2077
2078         bsec->set = 1;
2079         return 0;
2080 }
2081
2082 static int selinux_bprm_check_security(struct linux_binprm *bprm)
2083 {
2084         return secondary_ops->bprm_check_security(bprm);
2085 }
2086
2087
2088 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2089 {
2090         struct task_security_struct *tsec = current->security;
2091         int atsecure = 0;
2092
2093         if (tsec->osid != tsec->sid) {
2094                 /* Enable secure mode for SIDs transitions unless
2095                    the noatsecure permission is granted between
2096                    the two SIDs, i.e. ahp returns 0. */
2097                 atsecure = avc_has_perm(tsec->osid, tsec->sid,
2098                                          SECCLASS_PROCESS,
2099                                          PROCESS__NOATSECURE, NULL);
2100         }
2101
2102         return (atsecure || secondary_ops->bprm_secureexec(bprm));
2103 }
2104
2105 static void selinux_bprm_free_security(struct linux_binprm *bprm)
2106 {
2107         kfree(bprm->security);
2108         bprm->security = NULL;
2109 }
2110
2111 extern struct vfsmount *selinuxfs_mount;
2112 extern struct dentry *selinux_null;
2113
2114 /* Derived from fs/exec.c:flush_old_files. */
2115 static inline void flush_unauthorized_files(struct files_struct *files)
2116 {
2117         struct avc_audit_data ad;
2118         struct file *file, *devnull = NULL;
2119         struct tty_struct *tty;
2120         struct fdtable *fdt;
2121         long j = -1;
2122         int drop_tty = 0;
2123
2124         mutex_lock(&tty_mutex);
2125         tty = get_current_tty();
2126         if (tty) {
2127                 file_list_lock();
2128                 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
2129                 if (file) {
2130                         /* Revalidate access to controlling tty.
2131                            Use inode_has_perm on the tty inode directly rather
2132                            than using file_has_perm, as this particular open
2133                            file may belong to another process and we are only
2134                            interested in the inode-based check here. */
2135                         struct inode *inode = file->f_path.dentry->d_inode;
2136                         if (inode_has_perm(current, inode,
2137                                            FILE__READ | FILE__WRITE, NULL)) {
2138                                 drop_tty = 1;
2139                         }
2140                 }
2141                 file_list_unlock();
2142         }
2143         mutex_unlock(&tty_mutex);
2144         /* Reset controlling tty. */
2145         if (drop_tty)
2146                 no_tty();
2147
2148         /* Revalidate access to inherited open files. */
2149
2150         AVC_AUDIT_DATA_INIT(&ad, FS);
2151
2152         spin_lock(&files->file_lock);
2153         for (;;) {
2154                 unsigned long set, i;
2155                 int fd;
2156
2157                 j++;
2158                 i = j * __NFDBITS;
2159                 fdt = files_fdtable(files);
2160                 if (i >= fdt->max_fds)
2161                         break;
2162                 set = fdt->open_fds->fds_bits[j];
2163                 if (!set)
2164                         continue;
2165                 spin_unlock(&files->file_lock);
2166                 for ( ; set ; i++, set >>= 1) {
2167                         if (set & 1) {
2168                                 file = fget(i);
2169                                 if (!file)
2170                                         continue;
2171                                 if (file_has_perm(current,
2172                                                   file,
2173                                                   file_to_av(file))) {
2174                                         sys_close(i);
2175                                         fd = get_unused_fd();
2176                                         if (fd != i) {
2177                                                 if (fd >= 0)
2178                                                         put_unused_fd(fd);
2179                                                 fput(file);
2180                                                 continue;
2181                                         }
2182                                         if (devnull) {
2183                                                 get_file(devnull);
2184                                         } else {
2185                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
2186                                                 if (IS_ERR(devnull)) {
2187                                                         devnull = NULL;
2188                                                         put_unused_fd(fd);
2189                                                         fput(file);
2190                                                         continue;
2191                                                 }
2192                                         }
2193                                         fd_install(fd, devnull);
2194                                 }
2195                                 fput(file);
2196                         }
2197                 }
2198                 spin_lock(&files->file_lock);
2199
2200         }
2201         spin_unlock(&files->file_lock);
2202 }
2203
2204 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
2205 {
2206         struct task_security_struct *tsec;
2207         struct bprm_security_struct *bsec;
2208         u32 sid;
2209         int rc;
2210
2211         secondary_ops->bprm_apply_creds(bprm, unsafe);
2212
2213         tsec = current->security;
2214
2215         bsec = bprm->security;
2216         sid = bsec->sid;
2217
2218         tsec->osid = tsec->sid;
2219         bsec->unsafe = 0;
2220         if (tsec->sid != sid) {
2221                 /* Check for shared state.  If not ok, leave SID
2222                    unchanged and kill. */
2223                 if (unsafe & LSM_UNSAFE_SHARE) {
2224                         rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
2225                                         PROCESS__SHARE, NULL);
2226                         if (rc) {
2227                                 bsec->unsafe = 1;
2228                                 return;
2229                         }
2230                 }
2231
2232                 /* Check for ptracing, and update the task SID if ok.
2233                    Otherwise, leave SID unchanged and kill. */
2234                 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2235                         struct task_struct *tracer;
2236                         struct task_security_struct *sec;
2237                         u32 ptsid = 0;
2238
2239                         rcu_read_lock();
2240                         tracer = tracehook_tracer_task(current);
2241                         if (likely(tracer != NULL)) {
2242                                 sec = tracer->security;
2243                                 ptsid = sec->sid;
2244                         }
2245                         rcu_read_unlock();
2246
2247                         if (ptsid != 0) {
2248                                 rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
2249                                                   PROCESS__PTRACE, NULL);
2250                                 if (rc) {
2251                                         bsec->unsafe = 1;
2252                                         return;
2253                                 }
2254                         }
2255                 }
2256                 tsec->sid = sid;
2257         }
2258 }
2259
2260 /*
2261  * called after apply_creds without the task lock held
2262  */
2263 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
2264 {
2265         struct task_security_struct *tsec;
2266         struct rlimit *rlim, *initrlim;
2267         struct itimerval itimer;
2268         struct bprm_security_struct *bsec;
2269         int rc, i;
2270
2271         tsec = current->security;
2272         bsec = bprm->security;
2273
2274         if (bsec->unsafe) {
2275                 force_sig_specific(SIGKILL, current);
2276                 return;
2277         }
2278         if (tsec->osid == tsec->sid)
2279                 return;
2280
2281         /* Close files for which the new task SID is not authorized. */
2282         flush_unauthorized_files(current->files);
2283
2284         /* Check whether the new SID can inherit signal state
2285            from the old SID.  If not, clear itimers to avoid
2286            subsequent signal generation and flush and unblock
2287            signals. This must occur _after_ the task SID has
2288           been updated so that any kill done after the flush
2289           will be checked against the new SID. */
2290         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2291                           PROCESS__SIGINH, NULL);
2292         if (rc) {
2293                 memset(&itimer, 0, sizeof itimer);
2294                 for (i = 0; i < 3; i++)
2295                         do_setitimer(i, &itimer, NULL);
2296                 flush_signals(current);
2297                 spin_lock_irq(&current->sighand->siglock);
2298                 flush_signal_handlers(current, 1);
2299                 sigemptyset(&current->blocked);
2300                 recalc_sigpending();
2301                 spin_unlock_irq(&current->sighand->siglock);
2302         }
2303
2304         /* Always clear parent death signal on SID transitions. */
2305         current->pdeath_signal = 0;
2306
2307         /* Check whether the new SID can inherit resource limits
2308            from the old SID.  If not, reset all soft limits to
2309            the lower of the current task's hard limit and the init
2310            task's soft limit.  Note that the setting of hard limits
2311            (even to lower them) can be controlled by the setrlimit
2312            check. The inclusion of the init task's soft limit into
2313            the computation is to avoid resetting soft limits higher
2314            than the default soft limit for cases where the default
2315            is lower than the hard limit, e.g. RLIMIT_CORE or
2316            RLIMIT_STACK.*/
2317         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2318                           PROCESS__RLIMITINH, NULL);
2319         if (rc) {
2320                 for (i = 0; i < RLIM_NLIMITS; i++) {
2321                         rlim = current->signal->rlim + i;
2322                         initrlim = init_task.signal->rlim+i;
2323                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2324                 }
2325                 update_rlimit_cpu(rlim->rlim_cur);
2326         }
2327
2328         /* Wake up the parent if it is waiting so that it can
2329            recheck wait permission to the new task SID. */
2330         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2331 }
2332
2333 /* superblock security operations */
2334
2335 static int selinux_sb_alloc_security(struct super_block *sb)
2336 {
2337         return superblock_alloc_security(sb);
2338 }
2339
2340 static void selinux_sb_free_security(struct super_block *sb)
2341 {
2342         superblock_free_security(sb);
2343 }
2344
2345 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2346 {
2347         if (plen > olen)
2348                 return 0;
2349
2350         return !memcmp(prefix, option, plen);
2351 }
2352
2353 static inline int selinux_option(char *option, int len)
2354 {
2355         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2356                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2357                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2358                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len));
2359 }
2360
2361 static inline void take_option(char **to, char *from, int *first, int len)
2362 {
2363         if (!*first) {
2364                 **to = ',';
2365                 *to += 1;
2366         } else
2367                 *first = 0;
2368         memcpy(*to, from, len);
2369         *to += len;
2370 }
2371
2372 static inline void take_selinux_option(char **to, char *from, int *first,
2373                                        int len)
2374 {
2375         int current_size = 0;
2376
2377         if (!*first) {
2378                 **to = '|';
2379                 *to += 1;
2380         } else
2381                 *first = 0;
2382
2383         while (current_size < len) {
2384                 if (*from != '"') {
2385                         **to = *from;
2386                         *to += 1;
2387                 }
2388                 from += 1;
2389                 current_size += 1;
2390         }
2391 }
2392
2393 static int selinux_sb_copy_data(char *orig, char *copy)
2394 {
2395         int fnosec, fsec, rc = 0;
2396         char *in_save, *in_curr, *in_end;
2397         char *sec_curr, *nosec_save, *nosec;
2398         int open_quote = 0;
2399
2400         in_curr = orig;
2401         sec_curr = copy;
2402
2403         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2404         if (!nosec) {
2405                 rc = -ENOMEM;
2406                 goto out;
2407         }
2408
2409         nosec_save = nosec;
2410         fnosec = fsec = 1;
2411         in_save = in_end = orig;
2412
2413         do {
2414                 if (*in_end == '"')
2415                         open_quote = !open_quote;
2416                 if ((*in_end == ',' && open_quote == 0) ||
2417                                 *in_end == '\0') {
2418                         int len = in_end - in_curr;
2419
2420                         if (selinux_option(in_curr, len))
2421                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2422                         else
2423                                 take_option(&nosec, in_curr, &fnosec, len);
2424
2425                         in_curr = in_end + 1;
2426                 }
2427         } while (*in_end++);
2428
2429         strcpy(in_save, nosec_save);
2430         free_page((unsigned long)nosec_save);
2431 out:
2432         return rc;
2433 }
2434
2435 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2436 {
2437         struct avc_audit_data ad;
2438         int rc;
2439
2440         rc = superblock_doinit(sb, data);
2441         if (rc)
2442                 return rc;
2443
2444         AVC_AUDIT_DATA_INIT(&ad, FS);
2445         ad.u.fs.path.dentry = sb->s_root;
2446         return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2447 }
2448
2449 static int selinux_sb_statfs(struct dentry *dentry)
2450 {
2451         struct avc_audit_data ad;
2452
2453         AVC_AUDIT_DATA_INIT(&ad, FS);
2454         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2455         return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2456 }
2457
2458 static int selinux_mount(char *dev_name,
2459                          struct path *path,
2460                          char *type,
2461                          unsigned long flags,
2462                          void *data)
2463 {
2464         int rc;
2465
2466         rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
2467         if (rc)
2468                 return rc;
2469
2470         if (flags & MS_REMOUNT)
2471                 return superblock_has_perm(current, path->mnt->mnt_sb,
2472                                            FILESYSTEM__REMOUNT, NULL);
2473         else
2474                 return dentry_has_perm(current, path->mnt, path->dentry,
2475                                        FILE__MOUNTON);
2476 }
2477
2478 static int selinux_umount(struct vfsmount *mnt, int flags)
2479 {
2480         int rc;
2481
2482         rc = secondary_ops->sb_umount(mnt, flags);
2483         if (rc)
2484                 return rc;
2485
2486         return superblock_has_perm(current, mnt->mnt_sb,
2487                                    FILESYSTEM__UNMOUNT, NULL);
2488 }
2489
2490 /* inode security operations */
2491
2492 static int selinux_inode_alloc_security(struct inode *inode)
2493 {
2494         return inode_alloc_security(inode);
2495 }
2496
2497 static void selinux_inode_free_security(struct inode *inode)
2498 {
2499         inode_free_security(inode);
2500 }
2501
2502 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2503                                        char **name, void **value,
2504                                        size_t *len)
2505 {
2506         struct task_security_struct *tsec;
2507         struct inode_security_struct *dsec;
2508         struct superblock_security_struct *sbsec;
2509         u32 newsid, clen;
2510         int rc;
2511         char *namep = NULL, *context;
2512
2513         tsec = current->security;
2514         dsec = dir->i_security;
2515         sbsec = dir->i_sb->s_security;
2516
2517         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2518                 newsid = tsec->create_sid;
2519         } else {
2520                 rc = security_transition_sid(tsec->sid, dsec->sid,
2521                                              inode_mode_to_security_class(inode->i_mode),
2522                                              &newsid);
2523                 if (rc) {
2524                         printk(KERN_WARNING "%s:  "
2525                                "security_transition_sid failed, rc=%d (dev=%s "
2526                                "ino=%ld)\n",
2527                                __func__,
2528                                -rc, inode->i_sb->s_id, inode->i_ino);
2529                         return rc;
2530                 }
2531         }
2532
2533         /* Possibly defer initialization to selinux_complete_init. */
2534         if (sbsec->initialized) {
2535                 struct inode_security_struct *isec = inode->i_security;
2536                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2537                 isec->sid = newsid;
2538                 isec->initialized = 1;
2539         }
2540
2541         if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2542                 return -EOPNOTSUPP;
2543
2544         if (name) {
2545                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2546                 if (!namep)
2547                         return -ENOMEM;
2548                 *name = namep;
2549         }
2550
2551         if (value && len) {
2552                 rc = security_sid_to_context_force(newsid, &context, &clen);
2553                 if (rc) {
2554                         kfree(namep);
2555                         return rc;
2556                 }
2557                 *value = context;
2558                 *len = clen;
2559         }
2560
2561         return 0;
2562 }
2563
2564 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2565 {
2566         return may_create(dir, dentry, SECCLASS_FILE);
2567 }
2568
2569 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2570 {
2571         int rc;
2572
2573         rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
2574         if (rc)
2575                 return rc;
2576         return may_link(dir, old_dentry, MAY_LINK);
2577 }
2578
2579 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2580 {
2581         int rc;
2582
2583         rc = secondary_ops->inode_unlink(dir, dentry);
2584         if (rc)
2585                 return rc;
2586         return may_link(dir, dentry, MAY_UNLINK);
2587 }
2588
2589 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2590 {
2591         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2592 }
2593
2594 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2595 {
2596         return may_create(dir, dentry, SECCLASS_DIR);
2597 }
2598
2599 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2600 {
2601         return may_link(dir, dentry, MAY_RMDIR);
2602 }
2603
2604 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2605 {
2606         int rc;
2607
2608         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2609         if (rc)
2610                 return rc;
2611
2612         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2613 }
2614
2615 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2616                                 struct inode *new_inode, struct dentry *new_dentry)
2617 {
2618         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2619 }
2620
2621 static int selinux_inode_readlink(struct dentry *dentry)
2622 {
2623         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2624 }
2625
2626 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2627 {
2628         int rc;
2629
2630         rc = secondary_ops->inode_follow_link(dentry, nameidata);
2631         if (rc)
2632                 return rc;
2633         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2634 }
2635
2636 static int selinux_inode_permission(struct inode *inode, int mask)
2637 {
2638         int rc;
2639
2640         rc = secondary_ops->inode_permission(inode, mask);
2641         if (rc)
2642                 return rc;
2643
2644         if (!mask) {
2645                 /* No permission to check.  Existence test. */
2646                 return 0;
2647         }
2648
2649         return inode_has_perm(current, inode,
2650                                open_file_mask_to_av(inode->i_mode, mask), NULL);
2651 }
2652
2653 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2654 {
2655         int rc;
2656
2657         rc = secondary_ops->inode_setattr(dentry, iattr);
2658         if (rc)
2659                 return rc;
2660
2661         if (iattr->ia_valid & ATTR_FORCE)
2662                 return 0;
2663
2664         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2665                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2666                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2667
2668         return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2669 }
2670
2671 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2672 {
2673         return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2674 }
2675
2676 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2677 {
2678         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2679                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2680                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2681                         if (!capable(CAP_SETFCAP))
2682                                 return -EPERM;
2683                 } else if (!capable(CAP_SYS_ADMIN)) {
2684                         /* A different attribute in the security namespace.
2685                            Restrict to administrator. */
2686                         return -EPERM;
2687                 }
2688         }
2689
2690         /* Not an attribute we recognize, so just check the
2691            ordinary setattr permission. */
2692         return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2693 }
2694
2695 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2696                                   const void *value, size_t size, int flags)
2697 {
2698         struct task_security_struct *tsec = current->security;
2699         struct inode *inode = dentry->d_inode;
2700         struct inode_security_struct *isec = inode->i_security;
2701         struct superblock_security_struct *sbsec;
2702         struct avc_audit_data ad;
2703         u32 newsid;
2704         int rc = 0;
2705
2706         if (strcmp(name, XATTR_NAME_SELINUX))
2707                 return selinux_inode_setotherxattr(dentry, name);
2708
2709         sbsec = inode->i_sb->s_security;
2710         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2711                 return -EOPNOTSUPP;
2712
2713         if (!is_owner_or_cap(inode))
2714                 return -EPERM;
2715
2716         AVC_AUDIT_DATA_INIT(&ad, FS);
2717         ad.u.fs.path.dentry = dentry;
2718
2719         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2720                           FILE__RELABELFROM, &ad);
2721         if (rc)
2722                 return rc;
2723
2724         rc = security_context_to_sid(value, size, &newsid);
2725         if (rc == -EINVAL) {
2726                 if (!capable(CAP_MAC_ADMIN))
2727                         return rc;
2728                 rc = security_context_to_sid_force(value, size, &newsid);
2729         }
2730         if (rc)
2731                 return rc;
2732
2733         rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2734                           FILE__RELABELTO, &ad);
2735         if (rc)
2736                 return rc;
2737
2738         rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2739                                           isec->sclass);
2740         if (rc)
2741                 return rc;
2742
2743         return avc_has_perm(newsid,
2744                             sbsec->sid,
2745                             SECCLASS_FILESYSTEM,
2746                             FILESYSTEM__ASSOCIATE,
2747                             &ad);
2748 }
2749
2750 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2751                                         const void *value, size_t size,
2752                                         int flags)
2753 {
2754         struct inode *inode = dentry->d_inode;
2755         struct inode_security_struct *isec = inode->i_security;
2756         u32 newsid;
2757         int rc;
2758
2759         if (strcmp(name, XATTR_NAME_SELINUX)) {
2760                 /* Not an attribute we recognize, so nothing to do. */
2761                 return;
2762         }
2763
2764         rc = security_context_to_sid_force(value, size, &newsid);
2765         if (rc) {
2766                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2767                        "for (%s, %lu), rc=%d\n",
2768                        inode->i_sb->s_id, inode->i_ino, -rc);
2769                 return;
2770         }
2771
2772         isec->sid = newsid;
2773         return;
2774 }
2775
2776 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2777 {
2778         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2779 }
2780
2781 static int selinux_inode_listxattr(struct dentry *dentry)
2782 {
2783         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2784 }
2785
2786 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2787 {
2788         if (strcmp(name, XATTR_NAME_SELINUX))
2789                 return selinux_inode_setotherxattr(dentry, name);
2790
2791         /* No one is allowed to remove a SELinux security label.
2792            You can change the label, but all data must be labeled. */
2793         return -EACCES;
2794 }
2795
2796 /*
2797  * Copy the inode security context value to the user.
2798  *
2799  * Permission check is handled by selinux_inode_getxattr hook.
2800  */
2801 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2802 {
2803         u32 size;
2804         int error;
2805         char *context = NULL;
2806         struct task_security_struct *tsec = current->security;
2807         struct inode_security_struct *isec = inode->i_security;
2808
2809         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2810                 return -EOPNOTSUPP;
2811
2812         /*
2813          * If the caller has CAP_MAC_ADMIN, then get the raw context
2814          * value even if it is not defined by current policy; otherwise,
2815          * use the in-core value under current policy.
2816          * Use the non-auditing forms of the permission checks since
2817          * getxattr may be called by unprivileged processes commonly
2818          * and lack of permission just means that we fall back to the
2819          * in-core context value, not a denial.
2820          */
2821         error = secondary_ops->capable(current, CAP_MAC_ADMIN);
2822         if (!error)
2823                 error = avc_has_perm_noaudit(tsec->sid, tsec->sid,
2824                                              SECCLASS_CAPABILITY2,
2825                                              CAPABILITY2__MAC_ADMIN,
2826                                              0,
2827                                              NULL);
2828         if (!error)
2829                 error = security_sid_to_context_force(isec->sid, &context,
2830                                                       &size);
2831         else
2832                 error = security_sid_to_context(isec->sid, &context, &size);
2833         if (error)
2834                 return error;
2835         error = size;
2836         if (alloc) {
2837                 *buffer = context;
2838                 goto out_nofree;
2839         }
2840         kfree(context);
2841 out_nofree:
2842         return error;
2843 }
2844
2845 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2846                                      const void *value, size_t size, int flags)
2847 {
2848         struct inode_security_struct *isec = inode->i_security;
2849         u32 newsid;
2850         int rc;
2851
2852         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2853                 return -EOPNOTSUPP;
2854
2855         if (!value || !size)
2856                 return -EACCES;
2857
2858         rc = security_context_to_sid((void *)value, size, &newsid);
2859         if (rc)
2860                 return rc;
2861
2862         isec->sid = newsid;
2863         return 0;
2864 }
2865
2866 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2867 {
2868         const int len = sizeof(XATTR_NAME_SELINUX);
2869         if (buffer && len <= buffer_size)
2870                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2871         return len;
2872 }
2873
2874 static int selinux_inode_need_killpriv(struct dentry *dentry)
2875 {
2876         return secondary_ops->inode_need_killpriv(dentry);
2877 }
2878
2879 static int selinux_inode_killpriv(struct dentry *dentry)
2880 {
2881         return secondary_ops->inode_killpriv(dentry);
2882 }
2883
2884 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2885 {
2886         struct inode_security_struct *isec = inode->i_security;
2887         *secid = isec->sid;
2888 }
2889
2890 /* file security operations */
2891
2892 static int selinux_revalidate_file_permission(struct file *file, int mask)
2893 {
2894         int rc;
2895         struct inode *inode = file->f_path.dentry->d_inode;
2896
2897         if (!mask) {
2898                 /* No permission to check.  Existence test. */
2899                 return 0;
2900         }
2901
2902         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2903         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2904                 mask |= MAY_APPEND;
2905
2906         rc = file_has_perm(current, file,
2907                            file_mask_to_av(inode->i_mode, mask));
2908         if (rc)
2909                 return rc;
2910
2911         return selinux_netlbl_inode_permission(inode, mask);
2912 }
2913
2914 static int selinux_file_permission(struct file *file, int mask)
2915 {
2916         struct inode *inode = file->f_path.dentry->d_inode;
2917         struct task_security_struct *tsec = current->security;
2918         struct file_security_struct *fsec = file->f_security;
2919         struct inode_security_struct *isec = inode->i_security;
2920
2921         if (!mask) {
2922                 /* No permission to check.  Existence test. */
2923                 return 0;
2924         }
2925
2926         if (tsec->sid == fsec->sid && fsec->isid == isec->sid
2927             && fsec->pseqno == avc_policy_seqno())
2928                 return selinux_netlbl_inode_permission(inode, mask);
2929
2930         return selinux_revalidate_file_permission(file, mask);
2931 }
2932
2933 static int selinux_file_alloc_security(struct file *file)
2934 {
2935         return file_alloc_security(file);
2936 }
2937
2938 static void selinux_file_free_security(struct file *file)
2939 {
2940         file_free_security(file);
2941 }
2942
2943 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2944                               unsigned long arg)
2945 {
2946         u32 av = 0;
2947
2948         if (_IOC_DIR(cmd) & _IOC_WRITE)
2949                 av |= FILE__WRITE;
2950         if (_IOC_DIR(cmd) & _IOC_READ)
2951                 av |= FILE__READ;
2952         if (!av)
2953                 av = FILE__IOCTL;
2954
2955         return file_has_perm(current, file, av);
2956 }
2957
2958 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2959 {
2960 #ifndef CONFIG_PPC32
2961         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2962                 /*
2963                  * We are making executable an anonymous mapping or a
2964                  * private file mapping that will also be writable.
2965                  * This has an additional check.
2966                  */
2967                 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2968                 if (rc)
2969                         return rc;
2970         }
2971 #endif
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(current, file, av);
2985         }
2986         return 0;
2987 }
2988
2989 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2990                              unsigned long prot, unsigned long flags,
2991                              unsigned long addr, unsigned long addr_only)
2992 {
2993         int rc = 0;
2994         u32 sid = ((struct task_security_struct *)(current->security))->sid;
2995
2996         if (addr < mmap_min_addr)
2997                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
2998                                   MEMPROTECT__MMAP_ZERO, NULL);
2999         if (rc || addr_only)
3000                 return rc;
3001
3002         if (selinux_checkreqprot)
3003                 prot = reqprot;
3004
3005         return file_map_prot_check(file, prot,
3006                                    (flags & MAP_TYPE) == MAP_SHARED);
3007 }
3008
3009 static int selinux_file_mprotect(struct vm_area_struct *vma,
3010                                  unsigned long reqprot,
3011                                  unsigned long prot)
3012 {
3013         int rc;
3014
3015         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
3016         if (rc)
3017                 return rc;
3018
3019         if (selinux_checkreqprot)
3020                 prot = reqprot;
3021
3022 #ifndef CONFIG_PPC32
3023         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3024                 rc = 0;
3025                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3026                     vma->vm_end <= vma->vm_mm->brk) {
3027                         rc = task_has_perm(current, current,
3028                                            PROCESS__EXECHEAP);
3029                 } else if (!vma->vm_file &&
3030                            vma->vm_start <= vma->vm_mm->start_stack &&
3031                            vma->vm_end >= vma->vm_mm->start_stack) {
3032                         rc = task_has_perm(current, current, PROCESS__EXECSTACK);
3033                 } else if (vma->vm_file && vma->anon_vma) {
3034                         /*
3035                          * We are making executable a file mapping that has
3036                          * had some COW done. Since pages might have been
3037                          * written, check ability to execute the possibly
3038                          * modified content.  This typically should only
3039                          * occur for text relocations.
3040                          */
3041                         rc = file_has_perm(current, vma->vm_file,
3042                                            FILE__EXECMOD);
3043                 }
3044                 if (rc)
3045                         return rc;
3046         }
3047 #endif
3048
3049         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3050 }
3051
3052 static int selinux_file_lock(struct file *file, unsigned int cmd)
3053 {
3054         return file_has_perm(current, file, FILE__LOCK);
3055 }
3056
3057 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3058                               unsigned long arg)
3059 {
3060         int err = 0;
3061
3062         switch (cmd) {
3063         case F_SETFL:
3064                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3065                         err = -EINVAL;
3066                         break;
3067                 }
3068
3069                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3070                         err = file_has_perm(current, file, FILE__WRITE);
3071                         break;
3072                 }
3073                 /* fall through */
3074         case F_SETOWN:
3075         case F_SETSIG:
3076         case F_GETFL:
3077         case F_GETOWN:
3078         case F_GETSIG:
3079                 /* Just check FD__USE permission */
3080                 err = file_has_perm(current, file, 0);
3081                 break;
3082         case F_GETLK:
3083         case F_SETLK:
3084         case F_SETLKW:
3085 #if BITS_PER_LONG == 32
3086         case F_GETLK64:
3087         case F_SETLK64:
3088         case F_SETLKW64:
3089 #endif
3090                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3091                         err = -EINVAL;
3092                         break;
3093                 }
3094                 err = file_has_perm(current, file, FILE__LOCK);
3095                 break;
3096         }
3097
3098         return err;
3099 }
3100
3101 static int selinux_file_set_fowner(struct file *file)
3102 {
3103         struct task_security_struct *tsec;
3104         struct file_security_struct *fsec;
3105
3106         tsec = current->security;
3107         fsec = file->f_security;
3108         fsec->fown_sid = tsec->sid;
3109
3110         return 0;
3111 }
3112
3113 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3114                                        struct fown_struct *fown, int signum)
3115 {
3116         struct file *file;
3117         u32 perm;
3118         struct task_security_struct *tsec;
3119         struct file_security_struct *fsec;
3120
3121         /* struct fown_struct is never outside the context of a struct file */
3122         file = container_of(fown, struct file, f_owner);
3123
3124         tsec = tsk->security;
3125         fsec = file->f_security;
3126
3127         if (!signum)
3128                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3129         else
3130                 perm = signal_to_av(signum);
3131
3132         return avc_has_perm(fsec->fown_sid, tsec->sid,
3133                             SECCLASS_PROCESS, perm, NULL);
3134 }
3135
3136 static int selinux_file_receive(struct file *file)
3137 {
3138         return file_has_perm(current, file, file_to_av(file));
3139 }
3140
3141 static int selinux_dentry_open(struct file *file)
3142 {
3143         struct file_security_struct *fsec;
3144         struct inode *inode;
3145         struct inode_security_struct *isec;
3146         inode = file->f_path.dentry->d_inode;
3147         fsec = file->f_security;
3148         isec = inode->i_security;
3149         /*
3150          * Save inode label and policy sequence number
3151          * at open-time so that selinux_file_permission
3152          * can determine whether revalidation is necessary.
3153          * Task label is already saved in the file security
3154          * struct as its SID.
3155          */
3156         fsec->isid = isec->sid;
3157         fsec->pseqno = avc_policy_seqno();
3158         /*
3159          * Since the inode label or policy seqno may have changed
3160          * between the selinux_inode_permission check and the saving
3161          * of state above, recheck that access is still permitted.
3162          * Otherwise, access might never be revalidated against the
3163          * new inode label or new policy.
3164          * This check is not redundant - do not remove.
3165          */
3166         return inode_has_perm(current, inode, file_to_av(file), NULL);
3167 }
3168
3169 /* task security operations */
3170
3171 static int selinux_task_create(unsigned long clone_flags)
3172 {
3173         int rc;
3174
3175         rc = secondary_ops->task_create(clone_flags);
3176         if (rc)
3177                 return rc;
3178
3179         return task_has_perm(current, current, PROCESS__FORK);
3180 }
3181
3182 static int selinux_task_alloc_security(struct task_struct *tsk)
3183 {
3184         struct task_security_struct *tsec1, *tsec2;
3185         int rc;
3186
3187         tsec1 = current->security;
3188
3189         rc = task_alloc_security(tsk);
3190         if (rc)
3191                 return rc;
3192         tsec2 = tsk->security;
3193
3194         tsec2->osid = tsec1->osid;
3195         tsec2->sid = tsec1->sid;
3196
3197         /* Retain the exec, fs, key, and sock SIDs across fork */
3198         tsec2->exec_sid = tsec1->exec_sid;
3199         tsec2->create_sid = tsec1->create_sid;
3200         tsec2->keycreate_sid = tsec1->keycreate_sid;
3201         tsec2->sockcreate_sid = tsec1->sockcreate_sid;
3202
3203         return 0;
3204 }
3205
3206 static void selinux_task_free_security(struct task_struct *tsk)
3207 {
3208         task_free_security(tsk);
3209 }
3210
3211 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3212 {
3213         /* Since setuid only affects the current process, and
3214            since the SELinux controls are not based on the Linux
3215            identity attributes, SELinux does not need to control
3216            this operation.  However, SELinux does control the use
3217            of the CAP_SETUID and CAP_SETGID capabilities using the
3218            capable hook. */
3219         return 0;
3220 }
3221
3222 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3223 {
3224         return secondary_ops->task_post_setuid(id0, id1, id2, flags);
3225 }
3226
3227 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3228 {
3229         /* See the comment for setuid above. */
3230         return 0;
3231 }
3232
3233 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3234 {
3235         return task_has_perm(current, p, PROCESS__SETPGID);
3236 }
3237
3238 static int selinux_task_getpgid(struct task_struct *p)
3239 {
3240         return task_has_perm(current, p, PROCESS__GETPGID);
3241 }
3242
3243 static int selinux_task_getsid(struct task_struct *p)
3244 {
3245         return task_has_perm(current, p, PROCESS__GETSESSION);
3246 }
3247
3248 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3249 {
3250         struct task_security_struct *tsec = p->security;
3251         *secid = tsec->sid;
3252 }
3253
3254 static int selinux_task_setgroups(struct group_info *group_info)
3255 {
3256         /* See the comment for setuid above. */
3257         return 0;
3258 }
3259
3260 static int selinux_task_setnice(struct task_struct *p, int nice)
3261 {
3262         int rc;
3263
3264         rc = secondary_ops->task_setnice(p, nice);
3265         if (rc)
3266                 return rc;
3267
3268         return task_has_perm(current, p, PROCESS__SETSCHED);
3269 }
3270
3271 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3272 {
3273         int rc;
3274
3275         rc = secondary_ops->task_setioprio(p, ioprio);
3276         if (rc)
3277                 return rc;
3278
3279         return task_has_perm(current, p, PROCESS__SETSCHED);
3280 }
3281
3282 static int selinux_task_getioprio(struct task_struct *p)
3283 {
3284         return task_has_perm(current, p, PROCESS__GETSCHED);
3285 }
3286
3287 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3288 {
3289         struct rlimit *old_rlim = current->signal->rlim + resource;
3290         int rc;
3291
3292         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3293         if (rc)
3294                 return rc;
3295
3296         /* Control the ability to change the hard limit (whether
3297            lowering or raising it), so that the hard limit can
3298            later be used as a safe reset point for the soft limit
3299            upon context transitions. See selinux_bprm_apply_creds. */
3300         if (old_rlim->rlim_max != new_rlim->rlim_max)
3301                 return task_has_perm(current, current, PROCESS__SETRLIMIT);
3302
3303         return 0;
3304 }
3305
3306 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3307 {
3308         int rc;
3309
3310         rc = secondary_ops->task_setscheduler(p, policy, lp);
3311         if (rc)
3312                 return rc;
3313
3314         return task_has_perm(current, p, PROCESS__SETSCHED);
3315 }
3316
3317 static int selinux_task_getscheduler(struct task_struct *p)
3318 {
3319         return task_has_perm(current, p, PROCESS__GETSCHED);
3320 }
3321
3322 static int selinux_task_movememory(struct task_struct *p)
3323 {
3324         return task_has_perm(current, p, PROCESS__SETSCHED);
3325 }
3326
3327 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3328                                 int sig, u32 secid)
3329 {
3330         u32 perm;
3331         int rc;
3332         struct task_security_struct *tsec;
3333
3334         rc = secondary_ops->task_kill(p, info, sig, secid);
3335         if (rc)
3336                 return rc;
3337
3338         if (!sig)
3339                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3340         else
3341                 perm = signal_to_av(sig);
3342         tsec = p->security;
3343         if (secid)
3344                 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
3345         else
3346                 rc = task_has_perm(current, p, perm);
3347         return rc;
3348 }
3349
3350 static int selinux_task_prctl(int option,
3351                               unsigned long arg2,
3352                               unsigned long arg3,
3353                               unsigned long arg4,
3354                               unsigned long arg5,
3355                               long *rc_p)
3356 {
3357         /* The current prctl operations do not appear to require
3358            any SELinux controls since they merely observe or modify
3359            the state of the current process. */
3360         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p);
3361 }
3362
3363 static int selinux_task_wait(struct task_struct *p)
3364 {
3365         return task_has_perm(p, current, PROCESS__SIGCHLD);
3366 }
3367
3368 static void selinux_task_reparent_to_init(struct task_struct *p)
3369 {
3370         struct task_security_struct *tsec;
3371
3372         secondary_ops->task_reparent_to_init(p);
3373
3374         tsec = p->security;
3375         tsec->osid = tsec->sid;
3376         tsec->sid = SECINITSID_KERNEL;
3377         return;
3378 }
3379
3380 static void selinux_task_to_inode(struct task_struct *p,
3381                                   struct inode *inode)
3382 {
3383         struct task_security_struct *tsec = p->security;
3384         struct inode_security_struct *isec = inode->i_security;
3385
3386         isec->sid = tsec->sid;
3387         isec->initialized = 1;
3388         return;
3389 }
3390
3391 /* Returns error only if unable to parse addresses */
3392 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3393                         struct avc_audit_data *ad, u8 *proto)
3394 {
3395         int offset, ihlen, ret = -EINVAL;
3396         struct iphdr _iph, *ih;
3397
3398         offset = skb_network_offset(skb);
3399         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3400         if (ih == NULL)
3401                 goto out;
3402
3403         ihlen = ih->ihl * 4;
3404         if (ihlen < sizeof(_iph))
3405                 goto out;
3406
3407         ad->u.net.v4info.saddr = ih->saddr;
3408         ad->u.net.v4info.daddr = ih->daddr;
3409         ret = 0;
3410
3411         if (proto)
3412                 *proto = ih->protocol;
3413
3414         switch (ih->protocol) {
3415         case IPPROTO_TCP: {
3416                 struct tcphdr _tcph, *th;
3417
3418                 if (ntohs(ih->frag_off) & IP_OFFSET)
3419                         break;
3420
3421                 offset += ihlen;
3422                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3423                 if (th == NULL)
3424                         break;
3425
3426                 ad->u.net.sport = th->source;
3427                 ad->u.net.dport = th->dest;
3428                 break;
3429         }
3430
3431         case IPPROTO_UDP: {
3432                 struct udphdr _udph, *uh;
3433
3434                 if (ntohs(ih->frag_off) & IP_OFFSET)
3435                         break;
3436
3437                 offset += ihlen;
3438                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3439                 if (uh == NULL)
3440                         break;
3441
3442                 ad->u.net.sport = uh->source;
3443                 ad->u.net.dport = uh->dest;
3444                 break;
3445         }
3446
3447         case IPPROTO_DCCP: {
3448                 struct dccp_hdr _dccph, *dh;
3449
3450                 if (ntohs(ih->frag_off) & IP_OFFSET)
3451                         break;
3452
3453                 offset += ihlen;
3454                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3455                 if (dh == NULL)
3456                         break;
3457
3458                 ad->u.net.sport = dh->dccph_sport;
3459                 ad->u.net.dport = dh->dccph_dport;
3460                 break;
3461         }
3462
3463         default:
3464                 break;
3465         }
3466 out:
3467         return ret;
3468 }
3469
3470 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3471
3472 /* Returns error only if unable to parse addresses */
3473 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3474                         struct avc_audit_data *ad, u8 *proto)
3475 {
3476         u8 nexthdr;
3477         int ret = -EINVAL, offset;
3478         struct ipv6hdr _ipv6h, *ip6;
3479
3480         offset = skb_network_offset(skb);
3481         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3482         if (ip6 == NULL)
3483                 goto out;
3484
3485         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3486         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3487         ret = 0;
3488
3489         nexthdr = ip6->nexthdr;
3490         offset += sizeof(_ipv6h);
3491         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3492         if (offset < 0)
3493                 goto out;
3494
3495         if (proto)
3496                 *proto = nexthdr;
3497
3498         switch (nexthdr) {
3499         case IPPROTO_TCP: {
3500                 struct tcphdr _tcph, *th;
3501
3502                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3503                 if (th == NULL)
3504                         break;
3505
3506                 ad->u.net.sport = th->source;
3507                 ad->u.net.dport = th->dest;
3508                 break;
3509         }
3510
3511         case IPPROTO_UDP: {
3512                 struct udphdr _udph, *uh;
3513
3514                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3515                 if (uh == NULL)
3516                         break;
3517
3518                 ad->u.net.sport = uh->source;
3519                 ad->u.net.dport = uh->dest;
3520                 break;
3521         }
3522
3523         case IPPROTO_DCCP: {
3524                 struct dccp_hdr _dccph, *dh;
3525
3526                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3527                 if (dh == NULL)
3528                         break;
3529
3530                 ad->u.net.sport = dh->dccph_sport;
3531                 ad->u.net.dport = dh->dccph_dport;
3532                 break;
3533         }
3534
3535         /* includes fragments */
3536         default:
3537                 break;
3538         }
3539 out:
3540         return ret;
3541 }
3542
3543 #endif /* IPV6 */
3544
3545 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3546                              char **addrp, int src, u8 *proto)
3547 {
3548         int ret = 0;
3549
3550         switch (ad->u.net.family) {
3551         case PF_INET:
3552                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3553                 if (ret || !addrp)
3554                         break;
3555                 *addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3556                                         &ad->u.net.v4info.daddr);
3557                 break;
3558
3559 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3560         case PF_INET6:
3561                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3562                 if (ret || !addrp)
3563                         break;
3564                 *addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3565                                         &ad->u.net.v6info.daddr);
3566                 break;
3567 #endif  /* IPV6 */
3568         default:
3569                 break;
3570         }
3571
3572         if (unlikely(ret))
3573                 printk(KERN_WARNING
3574                        "SELinux: failure in selinux_parse_skb(),"
3575                        " unable to parse packet\n");
3576
3577         return ret;
3578 }
3579
3580 /**
3581  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3582  * @skb: the packet
3583  * @family: protocol family
3584  * @sid: the packet's peer label SID
3585  *
3586  * Description:
3587  * Check the various different forms of network peer labeling and determine
3588  * the peer label/SID for the packet; most of the magic actually occurs in
3589  * the security server function security_net_peersid_cmp().  The function
3590  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3591  * or -EACCES if @sid is invalid due to inconsistencies with the different
3592  * peer labels.
3593  *
3594  */
3595 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3596 {
3597         int err;
3598         u32 xfrm_sid;
3599         u32 nlbl_sid;
3600         u32 nlbl_type;
3601
3602         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3603         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3604
3605         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3606         if (unlikely(err)) {
3607                 printk(KERN_WARNING
3608                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3609                        " unable to determine packet's peer label\n");
3610                 return -EACCES;
3611         }
3612
3613         return 0;
3614 }
3615
3616 /* socket security operations */
3617 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3618                            u32 perms)
3619 {
3620         struct inode_security_struct *isec;
3621         struct task_security_struct *tsec;
3622         struct avc_audit_data ad;
3623         int err = 0;
3624
3625         tsec = task->security;
3626         isec = SOCK_INODE(sock)->i_security;
3627
3628         if (isec->sid == SECINITSID_KERNEL)
3629                 goto out;
3630
3631         AVC_AUDIT_DATA_INIT(&ad, NET);
3632         ad.u.net.sk = sock->sk;
3633         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3634
3635 out:
3636         return err;
3637 }
3638
3639 static int selinux_socket_create(int family, int type,
3640                                  int protocol, int kern)
3641 {
3642         int err = 0;
3643         struct task_security_struct *tsec;
3644         u32 newsid;
3645
3646         if (kern)
3647                 goto out;
3648
3649         tsec = current->security;
3650         newsid = tsec->sockcreate_sid ? : tsec->sid;
3651         err = avc_has_perm(tsec->sid, newsid,
3652                            socket_type_to_security_class(family, type,
3653                            protocol), SOCKET__CREATE, NULL);
3654
3655 out:
3656         return err;
3657 }
3658
3659 static int selinux_socket_post_create(struct socket *sock, int family,
3660                                       int type, int protocol, int kern)
3661 {
3662         int err = 0;
3663         struct inode_security_struct *isec;
3664         struct task_security_struct *tsec;
3665         struct sk_security_struct *sksec;
3666         u32 newsid;
3667
3668         isec = SOCK_INODE(sock)->i_security;
3669
3670         tsec = current->security;
3671         newsid = tsec->sockcreate_sid ? : tsec->sid;
3672         isec->sclass = socket_type_to_security_class(family, type, protocol);
3673         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3674         isec->initialized = 1;
3675
3676         if (sock->sk) {
3677                 sksec = sock->sk->sk_security;
3678                 sksec->sid = isec->sid;
3679                 sksec->sclass = isec->sclass;
3680                 err = selinux_netlbl_socket_post_create(sock);
3681         }
3682
3683         return err;
3684 }
3685
3686 /* Range of port numbers used to automatically bind.
3687    Need to determine whether we should perform a name_bind
3688    permission check between the socket and the port number. */
3689
3690 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3691 {
3692         u16 family;
3693         int err;
3694
3695         err = socket_has_perm(current, sock, SOCKET__BIND);
3696         if (err)
3697                 goto out;
3698
3699         /*
3700          * If PF_INET or PF_INET6, check name_bind permission for the port.
3701          * Multiple address binding for SCTP is not supported yet: we just
3702          * check the first address now.
3703          */
3704         family = sock->sk->sk_family;
3705         if (family == PF_INET || family == PF_INET6) {
3706                 char *addrp;
3707                 struct inode_security_struct *isec;
3708                 struct task_security_struct *tsec;
3709                 struct avc_audit_data ad;
3710                 struct sockaddr_in *addr4 = NULL;
3711                 struct sockaddr_in6 *addr6 = NULL;
3712                 unsigned short snum;
3713                 struct sock *sk = sock->sk;
3714                 u32 sid, node_perm;
3715
3716                 tsec = current->security;
3717                 isec = SOCK_INODE(sock)->i_security;
3718
3719                 if (family == PF_INET) {
3720                         addr4 = (struct sockaddr_in *)address;
3721                         snum = ntohs(addr4->sin_port);
3722                         addrp = (char *)&addr4->sin_addr.s_addr;
3723                 } else {
3724                         addr6 = (struct sockaddr_in6 *)address;
3725                         snum = ntohs(addr6->sin6_port);
3726                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3727                 }
3728
3729                 if (snum) {
3730                         int low, high;
3731
3732                         inet_get_local_port_range(&low, &high);
3733
3734                         if (snum < max(PROT_SOCK, low) || snum > high) {
3735                                 err = sel_netport_sid(sk->sk_protocol,
3736                                                       snum, &sid);
3737                                 if (err)
3738                                         goto out;
3739                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3740                                 ad.u.net.sport = htons(snum);
3741                                 ad.u.net.family = family;
3742                                 err = avc_has_perm(isec->sid, sid,
3743                                                    isec->sclass,
3744                                                    SOCKET__NAME_BIND, &ad);
3745                                 if (err)
3746                                         goto out;
3747                         }
3748                 }
3749
3750                 switch (isec->sclass) {
3751                 case SECCLASS_TCP_SOCKET:
3752                         node_perm = TCP_SOCKET__NODE_BIND;
3753                         break;
3754
3755                 case SECCLASS_UDP_SOCKET:
3756                         node_perm = UDP_SOCKET__NODE_BIND;
3757                         break;
3758
3759                 case SECCLASS_DCCP_SOCKET:
3760                         node_perm = DCCP_SOCKET__NODE_BIND;
3761                         break;
3762
3763                 default:
3764                         node_perm = RAWIP_SOCKET__NODE_BIND;
3765                         break;
3766                 }
3767
3768                 err = sel_netnode_sid(addrp, family, &sid);
3769                 if (err)
3770                         goto out;
3771
3772                 AVC_AUDIT_DATA_INIT(&ad, NET);
3773                 ad.u.net.sport = htons(snum);
3774                 ad.u.net.family = family;
3775
3776                 if (family == PF_INET)
3777                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3778                 else
3779                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3780
3781                 err = avc_has_perm(isec->sid, sid,
3782                                    isec->sclass, node_perm, &ad);
3783                 if (err)
3784                         goto out;
3785         }
3786 out:
3787         return err;
3788 }
3789
3790 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3791 {
3792         struct inode_security_struct *isec;
3793         int err;
3794
3795         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3796         if (err)
3797                 return err;
3798
3799         /*
3800          * If a TCP or DCCP socket, check name_connect permission for the port.
3801          */
3802         isec = SOCK_INODE(sock)->i_security;
3803         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3804             isec->sclass == SECCLASS_DCCP_SOCKET) {
3805                 struct sock *sk = sock->sk;
3806                 struct avc_audit_data ad;
3807                 struct sockaddr_in *addr4 = NULL;
3808                 struct sockaddr_in6 *addr6 = NULL;
3809                 unsigned short snum;
3810                 u32 sid, perm;
3811
3812                 if (sk->sk_family == PF_INET) {
3813                         addr4 = (struct sockaddr_in *)address;
3814                         if (addrlen < sizeof(struct sockaddr_in))
3815                                 return -EINVAL;
3816                         snum = ntohs(addr4->sin_port);
3817                 } else {
3818                         addr6 = (struct sockaddr_in6 *)address;
3819                         if (addrlen < SIN6_LEN_RFC2133)
3820                                 return -EINVAL;
3821                         snum = ntohs(addr6->sin6_port);
3822                 }
3823
3824                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3825                 if (err)
3826                         goto out;
3827
3828                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3829                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3830
3831                 AVC_AUDIT_DATA_INIT(&ad, NET);
3832                 ad.u.net.dport = htons(snum);
3833                 ad.u.net.family = sk->sk_family;
3834                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3835                 if (err)
3836                         goto out;
3837         }
3838
3839 out:
3840         return err;
3841 }
3842
3843 static int selinux_socket_listen(struct socket *sock, int backlog)
3844 {
3845         return socket_has_perm(current, sock, SOCKET__LISTEN);
3846 }
3847
3848 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3849 {
3850         int err;
3851         struct inode_security_struct *isec;
3852         struct inode_security_struct *newisec;
3853
3854         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3855         if (err)
3856                 return err;
3857
3858         newisec = SOCK_INODE(newsock)->i_security;
3859
3860         isec = SOCK_INODE(sock)->i_security;
3861         newisec->sclass = isec->sclass;
3862         newisec->sid = isec->sid;
3863         newisec->initialized = 1;
3864
3865         return 0;
3866 }
3867
3868 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3869                                   int size)
3870 {
3871         int rc;
3872
3873         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3874         if (rc)
3875                 return rc;
3876
3877         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3878 }
3879
3880 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3881                                   int size, int flags)
3882 {
3883         return socket_has_perm(current, sock, SOCKET__READ);
3884 }
3885
3886 static int selinux_socket_getsockname(struct socket *sock)
3887 {
3888         return socket_has_perm(current, sock, SOCKET__GETATTR);
3889 }
3890
3891 static int selinux_socket_getpeername(struct socket *sock)
3892 {
3893         return socket_has_perm(current, sock, SOCKET__GETATTR);
3894 }
3895
3896 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3897 {
3898         int err;
3899
3900         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3901         if (err)
3902                 return err;
3903
3904         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3905 }
3906
3907 static int selinux_socket_getsockopt(struct socket *sock, int level,
3908                                      int optname)
3909 {
3910         return socket_has_perm(current, sock, SOCKET__GETOPT);
3911 }
3912
3913 static int selinux_socket_shutdown(struct socket *sock, int how)
3914 {
3915         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3916 }
3917
3918 static int selinux_socket_unix_stream_connect(struct socket *sock,
3919                                               struct socket *other,
3920                                               struct sock *newsk)
3921 {
3922         struct sk_security_struct *ssec;
3923         struct inode_security_struct *isec;
3924         struct inode_security_struct *other_isec;
3925         struct avc_audit_data ad;
3926         int err;
3927
3928         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3929         if (err)
3930                 return err;
3931
3932         isec = SOCK_INODE(sock)->i_security;
3933         other_isec = SOCK_INODE(other)->i_security;
3934
3935         AVC_AUDIT_DATA_INIT(&ad, NET);
3936         ad.u.net.sk = other->sk;
3937
3938         err = avc_has_perm(isec->sid, other_isec->sid,
3939                            isec->sclass,
3940                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3941         if (err)
3942                 return err;
3943
3944         /* connecting socket */
3945         ssec = sock->sk->sk_security;
3946         ssec->peer_sid = other_isec->sid;
3947
3948         /* server child socket */
3949         ssec = newsk->sk_security;
3950         ssec->peer_sid = isec->sid;
3951         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3952
3953         return err;
3954 }
3955
3956 static int selinux_socket_unix_may_send(struct socket *sock,
3957                                         struct socket *other)
3958 {
3959         struct inode_security_struct *isec;
3960         struct inode_security_struct *other_isec;
3961         struct avc_audit_data ad;
3962         int err;
3963
3964         isec = SOCK_INODE(sock)->i_security;
3965         other_isec = SOCK_INODE(other)->i_security;
3966
3967         AVC_AUDIT_DATA_INIT(&ad, NET);
3968         ad.u.net.sk = other->sk;
3969
3970         err = avc_has_perm(isec->sid, other_isec->sid,
3971                            isec->sclass, SOCKET__SENDTO, &ad);
3972         if (err)
3973                 return err;
3974
3975         return 0;
3976 }
3977
3978 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3979                                     u32 peer_sid,
3980                                     struct avc_audit_data *ad)
3981 {
3982         int err;
3983         u32 if_sid;
3984         u32 node_sid;
3985
3986         err = sel_netif_sid(ifindex, &if_sid);
3987         if (err)
3988                 return err;
3989         err = avc_has_perm(peer_sid, if_sid,
3990                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3991         if (err)
3992                 return err;
3993
3994         err = sel_netnode_sid(addrp, family, &node_sid);
3995         if (err)
3996                 return err;
3997         return avc_has_perm(peer_sid, node_sid,
3998                             SECCLASS_NODE, NODE__RECVFROM, ad);
3999 }
4000
4001 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4002                                                 struct sk_buff *skb,
4003                                                 struct avc_audit_data *ad,
4004                                                 u16 family,
4005                                                 char *addrp)
4006 {
4007         int err;
4008         struct sk_security_struct *sksec = sk->sk_security;
4009         u16 sk_class;
4010         u32 netif_perm, node_perm, recv_perm;
4011         u32 port_sid, node_sid, if_sid, sk_sid;
4012
4013         sk_sid = sksec->sid;
4014         sk_class = sksec->sclass;
4015
4016         switch (sk_class) {
4017         case SECCLASS_UDP_SOCKET:
4018                 netif_perm = NETIF__UDP_RECV;
4019                 node_perm = NODE__UDP_RECV;
4020                 recv_perm = UDP_SOCKET__RECV_MSG;
4021                 break;
4022         case SECCLASS_TCP_SOCKET:
4023                 netif_perm = NETIF__TCP_RECV;
4024                 node_perm = NODE__TCP_RECV;
4025                 recv_perm = TCP_SOCKET__RECV_MSG;
4026                 break;
4027         case SECCLASS_DCCP_SOCKET:
4028                 netif_perm = NETIF__DCCP_RECV;
4029                 node_perm = NODE__DCCP_RECV;
4030                 recv_perm = DCCP_SOCKET__RECV_MSG;
4031                 break;
4032         default:
4033                 netif_perm = NETIF__RAWIP_RECV;
4034                 node_perm = NODE__RAWIP_RECV;
4035                 recv_perm = 0;
4036                 break;
4037         }
4038
4039         err = sel_netif_sid(skb->iif, &if_sid);
4040         if (err)
4041                 return err;
4042         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4043         if (err)
4044                 return err;
4045
4046         err = sel_netnode_sid(addrp, family, &node_sid);
4047         if (err)
4048                 return err;
4049         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4050         if (err)
4051                 return err;
4052
4053         if (!recv_perm)
4054                 return 0;
4055         err = sel_netport_sid(sk->sk_protocol,
4056                               ntohs(ad->u.net.sport), &port_sid);
4057         if (unlikely(err)) {
4058                 printk(KERN_WARNING
4059                        "SELinux: failure in"
4060                        " selinux_sock_rcv_skb_iptables_compat(),"
4061                        " network port label not found\n");
4062                 return err;
4063         }
4064         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4065 }
4066
4067 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4068                                        struct avc_audit_data *ad,
4069                                        u16 family, char *addrp)
4070 {
4071         int err;
4072         struct sk_security_struct *sksec = sk->sk_security;
4073         u32 peer_sid;
4074         u32 sk_sid = sksec->sid;
4075
4076         if (selinux_compat_net)
4077                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
4078                                                            family, addrp);
4079         else
4080                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4081                                    PACKET__RECV, ad);
4082         if (err)
4083                 return err;
4084
4085         if (selinux_policycap_netpeer) {
4086                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4087                 if (err)
4088                         return err;
4089                 err = avc_has_perm(sk_sid, peer_sid,
4090                                    SECCLASS_PEER, PEER__RECV, ad);
4091         } else {
4092                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
4093                 if (err)
4094                         return err;
4095                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
4096         }
4097
4098         return err;
4099 }
4100
4101 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4102 {
4103         int err;
4104         struct sk_security_struct *sksec = sk->sk_security;
4105         u16 family = sk->sk_family;
4106         u32 sk_sid = sksec->sid;
4107         struct avc_audit_data ad;
4108         char *addrp;
4109
4110         if (family != PF_INET && family != PF_INET6)
4111                 return 0;
4112
4113         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4114         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4115                 family = PF_INET;
4116
4117         AVC_AUDIT_DATA_INIT(&ad, NET);
4118         ad.u.net.netif = skb->iif;
4119         ad.u.net.family = family;
4120         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4121         if (err)
4122                 return err;
4123
4124         /* If any sort of compatibility mode is enabled then handoff processing
4125          * to the selinux_sock_rcv_skb_compat() function to deal with the
4126          * special handling.  We do this in an attempt to keep this function
4127          * as fast and as clean as possible. */
4128         if (selinux_compat_net || !selinux_policycap_netpeer)
4129                 return selinux_sock_rcv_skb_compat(sk, skb, &ad,
4130                                                    family, addrp);
4131
4132         if (netlbl_enabled() || selinux_xfrm_enabled()) {
4133                 u32 peer_sid;
4134
4135                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4136                 if (err)
4137                         return err;
4138                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4139                                                peer_sid, &ad);
4140                 if (err)
4141                         return err;
4142                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4143                                    PEER__RECV, &ad);
4144         }
4145
4146         if (selinux_secmark_enabled()) {
4147                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4148                                    PACKET__RECV, &ad);
4149                 if (err)
4150                         return err;
4151         }
4152
4153         return err;
4154 }
4155
4156 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4157                                             int __user *optlen, unsigned len)
4158 {
4159         int err = 0;
4160         char *scontext;
4161         u32 scontext_len;
4162         struct sk_security_struct *ssec;
4163         struct inode_security_struct *isec;
4164         u32 peer_sid = SECSID_NULL;
4165
4166         isec = SOCK_INODE(sock)->i_security;
4167
4168         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4169             isec->sclass == SECCLASS_TCP_SOCKET) {
4170                 ssec = sock->sk->sk_security;
4171                 peer_sid = ssec->peer_sid;
4172         }
4173         if (peer_sid == SECSID_NULL) {
4174                 err = -ENOPROTOOPT;
4175                 goto out;
4176         }
4177
4178         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4179
4180         if (err)
4181                 goto out;
4182
4183         if (scontext_len > len) {
4184                 err = -ERANGE;
4185                 goto out_len;
4186         }
4187
4188         if (copy_to_user(optval, scontext, scontext_len))
4189                 err = -EFAULT;
4190
4191 out_len:
4192         if (put_user(scontext_len, optlen))
4193                 err = -EFAULT;
4194
4195         kfree(scontext);
4196 out:
4197         return err;
4198 }
4199
4200 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4201 {
4202         u32 peer_secid = SECSID_NULL;
4203         u16 family;
4204
4205         if (sock)
4206                 family = sock->sk->sk_family;
4207         else if (skb && skb->sk)
4208                 family = skb->sk->sk_family;
4209         else
4210                 goto out;
4211
4212         if (sock && family == PF_UNIX)
4213                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4214         else if (skb)
4215                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4216
4217 out:
4218         *secid = peer_secid;
4219         if (peer_secid == SECSID_NULL)
4220                 return -EINVAL;
4221         return 0;
4222 }
4223
4224 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4225 {
4226         return sk_alloc_security(sk, family, priority);
4227 }
4228
4229 static void selinux_sk_free_security(struct sock *sk)
4230 {
4231         sk_free_security(sk);
4232 }
4233
4234 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4235 {
4236         struct sk_security_struct *ssec = sk->sk_security;
4237         struct sk_security_struct *newssec = newsk->sk_security;
4238
4239         newssec->sid = ssec->sid;
4240         newssec->peer_sid = ssec->peer_sid;
4241         newssec->sclass = ssec->sclass;
4242
4243         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4244 }
4245
4246 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4247 {
4248         if (!sk)
4249                 *secid = SECINITSID_ANY_SOCKET;
4250         else {
4251                 struct sk_security_struct *sksec = sk->sk_security;
4252
4253                 *secid = sksec->sid;
4254         }
4255 }
4256
4257 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4258 {
4259         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4260         struct sk_security_struct *sksec = sk->sk_security;
4261
4262         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4263             sk->sk_family == PF_UNIX)
4264                 isec->sid = sksec->sid;
4265         sksec->sclass = isec->sclass;
4266
4267         selinux_netlbl_sock_graft(sk, parent);
4268 }
4269
4270 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4271                                      struct request_sock *req)
4272 {
4273         struct sk_security_struct *sksec = sk->sk_security;
4274         int err;
4275         u32 newsid;
4276         u32 peersid;
4277
4278         err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
4279         if (err)
4280                 return err;
4281         if (peersid == SECSID_NULL) {
4282                 req->secid = sksec->sid;
4283                 req->peer_secid = SECSID_NULL;
4284                 return 0;
4285         }
4286
4287         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4288         if (err)
4289                 return err;
4290
4291         req->secid = newsid;
4292         req->peer_secid = peersid;
4293         return 0;
4294 }
4295
4296 static void selinux_inet_csk_clone(struct sock *newsk,
4297                                    const struct request_sock *req)
4298 {
4299         struct sk_security_struct *newsksec = newsk->sk_security;
4300
4301         newsksec->sid = req->secid;
4302         newsksec->peer_sid = req->peer_secid;
4303         /* NOTE: Ideally, we should also get the isec->sid for the
4304            new socket in sync, but we don't have the isec available yet.
4305            So we will wait until sock_graft to do it, by which
4306            time it will have been created and available. */
4307
4308         /* We don't need to take any sort of lock here as we are the only
4309          * thread with access to newsksec */
4310         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4311 }
4312
4313 static void selinux_inet_conn_established(struct sock *sk,
4314                                 struct sk_buff *skb)
4315 {
4316         struct sk_security_struct *sksec = sk->sk_security;
4317
4318         selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
4319 }
4320
4321 static void selinux_req_classify_flow(const struct request_sock *req,
4322                                       struct flowi *fl)
4323 {
4324         fl->secid = req->secid;
4325 }
4326
4327 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4328 {
4329         int err = 0;
4330         u32 perm;
4331         struct nlmsghdr *nlh;
4332         struct socket *sock = sk->sk_socket;
4333         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4334
4335         if (skb->len < NLMSG_SPACE(0)) {
4336                 err = -EINVAL;
4337                 goto out;
4338         }
4339         nlh = nlmsg_hdr(skb);
4340
4341         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4342         if (err) {
4343                 if (err == -EINVAL) {
4344                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4345                                   "SELinux:  unrecognized netlink message"
4346                                   " type=%hu for sclass=%hu\n",
4347                                   nlh->nlmsg_type, isec->sclass);
4348                         if (!selinux_enforcing)
4349                                 err = 0;
4350                 }
4351
4352                 /* Ignore */
4353                 if (err == -ENOENT)
4354                         err = 0;
4355                 goto out;
4356         }
4357
4358         err = socket_has_perm(current, sock, perm);
4359 out:
4360         return err;
4361 }
4362
4363 #ifdef CONFIG_NETFILTER
4364
4365 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4366                                        u16 family)
4367 {
4368         char *addrp;
4369         u32 peer_sid;
4370         struct avc_audit_data ad;
4371         u8 secmark_active;
4372         u8 peerlbl_active;
4373
4374         if (!selinux_policycap_netpeer)
4375                 return NF_ACCEPT;
4376
4377         secmark_active = selinux_secmark_enabled();
4378         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4379         if (!secmark_active && !peerlbl_active)
4380                 return NF_ACCEPT;
4381
4382         AVC_AUDIT_DATA_INIT(&ad, NET);
4383         ad.u.net.netif = ifindex;
4384         ad.u.net.family = family;
4385         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4386                 return NF_DROP;
4387
4388         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4389                 return NF_DROP;
4390
4391         if (peerlbl_active)
4392                 if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4393                                              peer_sid, &ad) != 0)
4394                         return NF_DROP;
4395
4396         if (secmark_active)
4397                 if (avc_has_perm(peer_sid, skb->secmark,
4398                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4399                         return NF_DROP;
4400
4401         return NF_ACCEPT;
4402 }
4403
4404 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4405                                          struct sk_buff *skb,
4406                                          const struct net_device *in,
4407                                          const struct net_device *out,
4408                                          int (*okfn)(struct sk_buff *))
4409 {
4410         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4411 }
4412
4413 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4414 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4415                                          struct sk_buff *skb,
4416                                          const struct net_device *in,
4417                                          const struct net_device *out,
4418                                          int (*okfn)(struct sk_buff *))
4419 {
4420         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4421 }
4422 #endif  /* IPV6 */
4423
4424 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4425                                                 int ifindex,
4426                                                 struct avc_audit_data *ad,
4427                                                 u16 family, char *addrp)
4428 {
4429         int err;
4430         struct sk_security_struct *sksec = sk->sk_security;
4431         u16 sk_class;
4432         u32 netif_perm, node_perm, send_perm;
4433         u32 port_sid, node_sid, if_sid, sk_sid;
4434
4435         sk_sid = sksec->sid;
4436         sk_class = sksec->sclass;
4437
4438         switch (sk_class) {
4439         case SECCLASS_UDP_SOCKET:
4440                 netif_perm = NETIF__UDP_SEND;
4441                 node_perm = NODE__UDP_SEND;
4442                 send_perm = UDP_SOCKET__SEND_MSG;
4443                 break;
4444         case SECCLASS_TCP_SOCKET:
4445                 netif_perm = NETIF__TCP_SEND;
4446                 node_perm = NODE__TCP_SEND;
4447                 send_perm = TCP_SOCKET__SEND_MSG;
4448                 break;
4449         case SECCLASS_DCCP_SOCKET:
4450                 netif_perm = NETIF__DCCP_SEND;
4451                 node_perm = NODE__DCCP_SEND;
4452                 send_perm = DCCP_SOCKET__SEND_MSG;
4453                 break;
4454         default:
4455                 netif_perm = NETIF__RAWIP_SEND;
4456                 node_perm = NODE__RAWIP_SEND;
4457                 send_perm = 0;
4458                 break;
4459         }
4460
4461         err = sel_netif_sid(ifindex, &if_sid);
4462         if (err)
4463                 return err;
4464         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4465                 return err;
4466
4467         err = sel_netnode_sid(addrp, family, &node_sid);
4468         if (err)
4469                 return err;
4470         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4471         if (err)
4472                 return err;
4473
4474         if (send_perm != 0)
4475                 return 0;
4476
4477         err = sel_netport_sid(sk->sk_protocol,
4478                               ntohs(ad->u.net.dport), &port_sid);
4479         if (unlikely(err)) {
4480                 printk(KERN_WARNING
4481                        "SELinux: failure in"
4482                        " selinux_ip_postroute_iptables_compat(),"
4483                        " network port label not found\n");
4484                 return err;
4485         }
4486         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4487 }
4488
4489 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4490                                                 int ifindex,
4491                                                 struct avc_audit_data *ad,
4492                                                 u16 family,
4493                                                 char *addrp,
4494                                                 u8 proto)
4495 {
4496         struct sock *sk = skb->sk;
4497         struct sk_security_struct *sksec;
4498
4499         if (sk == NULL)
4500                 return NF_ACCEPT;
4501         sksec = sk->sk_security;
4502
4503         if (selinux_compat_net) {
4504                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4505                                                          ad, family, addrp))
4506                         return NF_DROP;
4507         } else {
4508                 if (avc_has_perm(sksec->sid, skb->secmark,
4509                                  SECCLASS_PACKET, PACKET__SEND, ad))
4510                         return NF_DROP;
4511         }
4512
4513         if (selinux_policycap_netpeer)
4514                 if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto))
4515                         return NF_DROP;
4516
4517         return NF_ACCEPT;
4518 }
4519
4520 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4521                                          u16 family)
4522 {
4523         u32 secmark_perm;
4524         u32 peer_sid;
4525         struct sock *sk;
4526         struct avc_audit_data ad;
4527         char *addrp;
4528         u8 proto;
4529         u8 secmark_active;
4530         u8 peerlbl_active;
4531
4532         AVC_AUDIT_DATA_INIT(&ad, NET);
4533         ad.u.net.netif = ifindex;
4534         ad.u.net.family = family;
4535         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4536                 return NF_DROP;
4537
4538         /* If any sort of compatibility mode is enabled then handoff processing
4539          * to the selinux_ip_postroute_compat() function to deal with the
4540          * special handling.  We do this in an attempt to keep this function
4541          * as fast and as clean as possible. */
4542         if (selinux_compat_net || !selinux_policycap_netpeer)
4543                 return selinux_ip_postroute_compat(skb, ifindex, &ad,
4544                                                    family, addrp, proto);
4545
4546         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4547          * packet transformation so allow the packet to pass without any checks
4548          * since we'll have another chance to perform access control checks
4549          * when the packet is on it's final way out.
4550          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4551          *       is NULL, in this case go ahead and apply access control. */
4552         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4553                 return NF_ACCEPT;
4554
4555         secmark_active = selinux_secmark_enabled();
4556         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4557         if (!secmark_active && !peerlbl_active)
4558                 return NF_ACCEPT;
4559
4560         /* if the packet is locally generated (skb->sk != NULL) then use the
4561          * socket's label as the peer label, otherwise the packet is being
4562          * forwarded through this system and we need to fetch the peer label
4563          * directly from the packet */
4564         sk = skb->sk;
4565         if (sk) {
4566                 struct sk_security_struct *sksec = sk->sk_security;
4567                 peer_sid = sksec->sid;
4568                 secmark_perm = PACKET__SEND;
4569         } else {
4570                 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4571                                 return NF_DROP;
4572                 secmark_perm = PACKET__FORWARD_OUT;
4573         }
4574
4575         if (secmark_active)
4576                 if (avc_has_perm(peer_sid, skb->secmark,
4577                                  SECCLASS_PACKET, secmark_perm, &ad))
4578                         return NF_DROP;
4579
4580         if (peerlbl_active) {
4581                 u32 if_sid;
4582                 u32 node_sid;
4583
4584                 if (sel_netif_sid(ifindex, &if_sid))
4585                         return NF_DROP;
4586                 if (avc_has_perm(peer_sid, if_sid,
4587                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4588                         return NF_DROP;
4589
4590                 if (sel_netnode_sid(addrp, family, &node_sid))
4591                         return NF_DROP;
4592                 if (avc_has_perm(peer_sid, node_sid,
4593                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4594                         return NF_DROP;
4595         }
4596
4597         return NF_ACCEPT;
4598 }
4599
4600 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4601                                            struct sk_buff *skb,
4602                                            const struct net_device *in,
4603                                            const struct net_device *out,
4604                                            int (*okfn)(struct sk_buff *))
4605 {
4606         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4607 }
4608
4609 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4610 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4611                                            struct sk_buff *skb,
4612                                            const struct net_device *in,
4613                                            const struct net_device *out,
4614                                            int (*okfn)(struct sk_buff *))
4615 {
4616         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4617 }
4618 #endif  /* IPV6 */
4619
4620 #endif  /* CONFIG_NETFILTER */
4621
4622 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4623 {
4624         int err;
4625
4626         err = secondary_ops->netlink_send(sk, skb);
4627         if (err)
4628                 return err;
4629
4630         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4631                 err = selinux_nlmsg_perm(sk, skb);
4632
4633         return err;
4634 }
4635
4636 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4637 {
4638         int err;
4639         struct avc_audit_data ad;
4640
4641         err = secondary_ops->netlink_recv(skb, capability);
4642         if (err)
4643                 return err;
4644
4645         AVC_AUDIT_DATA_INIT(&ad, CAP);
4646         ad.u.cap = capability;
4647
4648         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4649                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4650 }
4651
4652 static int ipc_alloc_security(struct task_struct *task,
4653                               struct kern_ipc_perm *perm,
4654                               u16 sclass)
4655 {
4656         struct task_security_struct *tsec = task->security;
4657         struct ipc_security_struct *isec;
4658
4659         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4660         if (!isec)
4661                 return -ENOMEM;
4662
4663         isec->sclass = sclass;
4664         isec->sid = tsec->sid;
4665         perm->security = isec;
4666
4667         return 0;
4668 }
4669
4670 static void ipc_free_security(struct kern_ipc_perm *perm)
4671 {
4672         struct ipc_security_struct *isec = perm->security;
4673         perm->security = NULL;
4674         kfree(isec);
4675 }
4676
4677 static int msg_msg_alloc_security(struct msg_msg *msg)
4678 {
4679         struct msg_security_struct *msec;
4680
4681         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4682         if (!msec)
4683                 return -ENOMEM;
4684
4685         msec->sid = SECINITSID_UNLABELED;
4686         msg->security = msec;
4687
4688         return 0;
4689 }
4690
4691 static void msg_msg_free_security(struct msg_msg *msg)
4692 {
4693         struct msg_security_struct *msec = msg->security;
4694
4695         msg->security = NULL;
4696         kfree(msec);
4697 }
4698
4699 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4700                         u32 perms)
4701 {
4702         struct task_security_struct *tsec;
4703         struct ipc_security_struct *isec;
4704         struct avc_audit_data ad;
4705
4706         tsec = current->security;
4707         isec = ipc_perms->security;
4708
4709         AVC_AUDIT_DATA_INIT(&ad, IPC);
4710         ad.u.ipc_id = ipc_perms->key;
4711
4712         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
4713 }
4714
4715 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4716 {
4717         return msg_msg_alloc_security(msg);
4718 }
4719
4720 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4721 {
4722         msg_msg_free_security(msg);
4723 }
4724
4725 /* message queue security operations */
4726 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4727 {
4728         struct task_security_struct *tsec;
4729         struct ipc_security_struct *isec;
4730         struct avc_audit_data ad;
4731         int rc;
4732
4733         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4734         if (rc)
4735                 return rc;
4736
4737         tsec = current->security;
4738         isec = msq->q_perm.security;
4739
4740         AVC_AUDIT_DATA_INIT(&ad, IPC);
4741         ad.u.ipc_id = msq->q_perm.key;
4742
4743         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4744                           MSGQ__CREATE, &ad);
4745         if (rc) {
4746                 ipc_free_security(&msq->q_perm);
4747                 return rc;
4748         }
4749         return 0;
4750 }
4751
4752 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4753 {
4754         ipc_free_security(&msq->q_perm);
4755 }
4756
4757 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4758 {
4759         struct task_security_struct *tsec;
4760         struct ipc_security_struct *isec;
4761         struct avc_audit_data ad;
4762
4763         tsec = current->security;
4764         isec = msq->q_perm.security;
4765
4766         AVC_AUDIT_DATA_INIT(&ad, IPC);
4767         ad.u.ipc_id = msq->q_perm.key;
4768
4769         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4770                             MSGQ__ASSOCIATE, &ad);
4771 }
4772
4773 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4774 {
4775         int err;
4776         int perms;
4777
4778         switch (cmd) {
4779         case IPC_INFO:
4780         case MSG_INFO:
4781                 /* No specific object, just general system-wide information. */
4782                 return task_has_system(current, SYSTEM__IPC_INFO);
4783         case IPC_STAT:
4784         case MSG_STAT:
4785                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4786                 break;
4787         case IPC_SET:
4788                 perms = MSGQ__SETATTR;
4789                 break;
4790         case IPC_RMID:
4791                 perms = MSGQ__DESTROY;
4792                 break;
4793         default:
4794                 return 0;
4795         }
4796
4797         err = ipc_has_perm(&msq->q_perm, perms);
4798         return err;
4799 }
4800
4801 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4802 {
4803         struct task_security_struct *tsec;
4804         struct ipc_security_struct *isec;
4805         struct msg_security_struct *msec;
4806         struct avc_audit_data ad;
4807         int rc;
4808
4809         tsec = current->security;
4810         isec = msq->q_perm.security;
4811         msec = msg->security;
4812
4813         /*
4814          * First time through, need to assign label to the message
4815          */
4816         if (msec->sid == SECINITSID_UNLABELED) {
4817                 /*
4818                  * Compute new sid based on current process and
4819                  * message queue this message will be stored in
4820                  */
4821                 rc = security_transition_sid(tsec->sid,
4822                                              isec->sid,
4823                                              SECCLASS_MSG,
4824                                              &msec->sid);
4825                 if (rc)
4826                         return rc;
4827         }
4828
4829         AVC_AUDIT_DATA_INIT(&ad, IPC);
4830         ad.u.ipc_id = msq->q_perm.key;
4831
4832         /* Can this process write to the queue? */
4833         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4834                           MSGQ__WRITE, &ad);
4835         if (!rc)
4836                 /* Can this process send the message */
4837                 rc = avc_has_perm(tsec->sid, msec->sid,
4838                                   SECCLASS_MSG, MSG__SEND, &ad);
4839         if (!rc)
4840                 /* Can the message be put in the queue? */
4841                 rc = avc_has_perm(msec->sid, isec->sid,
4842                                   SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
4843
4844         return rc;
4845 }
4846
4847 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4848                                     struct task_struct *target,
4849                                     long type, int mode)
4850 {
4851         struct task_security_struct *tsec;
4852         struct ipc_security_struct *isec;
4853         struct msg_security_struct *msec;
4854         struct avc_audit_data ad;
4855         int rc;
4856
4857         tsec = target->security;
4858         isec = msq->q_perm.security;
4859         msec = msg->security;
4860
4861         AVC_AUDIT_DATA_INIT(&ad, IPC);
4862         ad.u.ipc_id = msq->q_perm.key;
4863
4864         rc = avc_has_perm(tsec->sid, isec->sid,
4865                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4866         if (!rc)
4867                 rc = avc_has_perm(tsec->sid, msec->sid,
4868                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4869         return rc;
4870 }
4871
4872 /* Shared Memory security operations */
4873 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4874 {
4875         struct task_security_struct *tsec;
4876         struct ipc_security_struct *isec;
4877         struct avc_audit_data ad;
4878         int rc;
4879
4880         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4881         if (rc)
4882                 return rc;
4883
4884         tsec = current->security;
4885         isec = shp->shm_perm.security;
4886
4887         AVC_AUDIT_DATA_INIT(&ad, IPC);
4888         ad.u.ipc_id = shp->shm_perm.key;
4889
4890         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4891                           SHM__CREATE, &ad);
4892         if (rc) {
4893                 ipc_free_security(&shp->shm_perm);
4894                 return rc;
4895         }
4896         return 0;
4897 }
4898
4899 static void selinux_shm_free_security(struct shmid_kernel *shp)
4900 {
4901         ipc_free_security(&shp->shm_perm);
4902 }
4903
4904 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4905 {
4906         struct task_security_struct *tsec;
4907         struct ipc_security_struct *isec;
4908         struct avc_audit_data ad;
4909
4910         tsec = current->security;
4911         isec = shp->shm_perm.security;
4912
4913         AVC_AUDIT_DATA_INIT(&ad, IPC);
4914         ad.u.ipc_id = shp->shm_perm.key;
4915
4916         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4917                             SHM__ASSOCIATE, &ad);
4918 }
4919
4920 /* Note, at this point, shp is locked down */
4921 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4922 {
4923         int perms;
4924         int err;
4925
4926         switch (cmd) {
4927         case IPC_INFO:
4928         case SHM_INFO:
4929                 /* No specific object, just general system-wide information. */
4930                 return task_has_system(current, SYSTEM__IPC_INFO);
4931         case IPC_STAT:
4932         case SHM_STAT:
4933                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4934                 break;
4935         case IPC_SET:
4936                 perms = SHM__SETATTR;
4937                 break;
4938         case SHM_LOCK:
4939         case SHM_UNLOCK:
4940                 perms = SHM__LOCK;
4941                 break;
4942         case IPC_RMID:
4943                 perms = SHM__DESTROY;
4944                 break;
4945         default:
4946                 return 0;
4947         }
4948
4949         err = ipc_has_perm(&shp->shm_perm, perms);
4950         return err;
4951 }
4952
4953 static int selinux_shm_shmat(struct shmid_kernel *shp,
4954                              char __user *shmaddr, int shmflg)
4955 {
4956         u32 perms;
4957         int rc;
4958
4959         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
4960         if (rc)
4961                 return rc;
4962
4963         if (shmflg & SHM_RDONLY)
4964                 perms = SHM__READ;
4965         else
4966                 perms = SHM__READ | SHM__WRITE;
4967
4968         return ipc_has_perm(&shp->shm_perm, perms);
4969 }
4970
4971 /* Semaphore security operations */
4972 static int selinux_sem_alloc_security(struct sem_array *sma)
4973 {
4974         struct task_security_struct *tsec;
4975         struct ipc_security_struct *isec;
4976         struct avc_audit_data ad;
4977         int rc;
4978
4979         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4980         if (rc)
4981                 return rc;
4982
4983         tsec = current->security;
4984         isec = sma->sem_perm.security;
4985
4986         AVC_AUDIT_DATA_INIT(&ad, IPC);
4987         ad.u.ipc_id = sma->sem_perm.key;
4988
4989         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4990                           SEM__CREATE, &ad);
4991         if (rc) {
4992                 ipc_free_security(&sma->sem_perm);
4993                 return rc;
4994         }
4995         return 0;
4996 }
4997
4998 static void selinux_sem_free_security(struct sem_array *sma)
4999 {
5000         ipc_free_security(&sma->sem_perm);
5001 }
5002
5003 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5004 {
5005         struct task_security_struct *tsec;
5006         struct ipc_security_struct *isec;
5007         struct avc_audit_data ad;
5008
5009         tsec = current->security;
5010         isec = sma->sem_perm.security;
5011
5012         AVC_AUDIT_DATA_INIT(&ad, IPC);
5013         ad.u.ipc_id = sma->sem_perm.key;
5014
5015         return avc_has_perm(tsec->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         struct task_security_struct *tsec;
5106         u32 sid;
5107         int error;
5108         unsigned len;
5109
5110         if (current != p) {
5111                 error = task_has_perm(current, p, PROCESS__GETATTR);
5112                 if (error)
5113                         return error;
5114         }
5115
5116         tsec = p->security;
5117
5118         if (!strcmp(name, "current"))
5119                 sid = tsec->sid;
5120         else if (!strcmp(name, "prev"))
5121                 sid = tsec->osid;
5122         else if (!strcmp(name, "exec"))
5123                 sid = tsec->exec_sid;
5124         else if (!strcmp(name, "fscreate"))
5125                 sid = tsec->create_sid;
5126         else if (!strcmp(name, "keycreate"))
5127                 sid = tsec->keycreate_sid;
5128         else if (!strcmp(name, "sockcreate"))
5129                 sid = tsec->sockcreate_sid;
5130         else
5131                 return -EINVAL;
5132
5133         if (!sid)
5134                 return 0;
5135
5136         error = security_sid_to_context(sid, value, &len);
5137         if (error)
5138                 return error;
5139         return len;
5140 }
5141
5142 static int selinux_setprocattr(struct task_struct *p,
5143                                char *name, void *value, size_t size)
5144 {
5145         struct task_security_struct *tsec;
5146         struct task_struct *tracer;
5147         u32 sid = 0;
5148         int error;
5149         char *str = value;
5150
5151         if (current != p) {
5152                 /* SELinux only allows a process to change its own
5153                    security attributes. */
5154                 return -EACCES;
5155         }
5156
5157         /*
5158          * Basic control over ability to set these attributes at all.
5159          * current == p, but we'll pass them separately in case the
5160          * above restriction is ever removed.
5161          */
5162         if (!strcmp(name, "exec"))
5163                 error = task_has_perm(current, p, PROCESS__SETEXEC);
5164         else if (!strcmp(name, "fscreate"))
5165                 error = task_has_perm(current, p, PROCESS__SETFSCREATE);
5166         else if (!strcmp(name, "keycreate"))
5167                 error = task_has_perm(current, p, PROCESS__SETKEYCREATE);
5168         else if (!strcmp(name, "sockcreate"))
5169                 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE);
5170         else if (!strcmp(name, "current"))
5171                 error = task_has_perm(current, p, PROCESS__SETCURRENT);
5172         else
5173                 error = -EINVAL;
5174         if (error)
5175                 return error;
5176
5177         /* Obtain a SID for the context, if one was specified. */
5178         if (size && str[1] && str[1] != '\n') {
5179                 if (str[size-1] == '\n') {
5180                         str[size-1] = 0;
5181                         size--;
5182                 }
5183                 error = security_context_to_sid(value, size, &sid);
5184                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5185                         if (!capable(CAP_MAC_ADMIN))
5186                                 return error;
5187                         error = security_context_to_sid_force(value, size,
5188                                                               &sid);
5189                 }
5190                 if (error)
5191                         return error;
5192         }
5193
5194         /* Permission checking based on the specified context is
5195            performed during the actual operation (execve,
5196            open/mkdir/...), when we know the full context of the
5197            operation.  See selinux_bprm_set_security for the execve
5198            checks and may_create for the file creation checks. The
5199            operation will then fail if the context is not permitted. */
5200         tsec = p->security;
5201         if (!strcmp(name, "exec"))
5202                 tsec->exec_sid = sid;
5203         else if (!strcmp(name, "fscreate"))
5204                 tsec->create_sid = sid;
5205         else if (!strcmp(name, "keycreate")) {
5206                 error = may_create_key(sid, p);
5207                 if (error)
5208                         return error;
5209                 tsec->keycreate_sid = sid;
5210         } else if (!strcmp(name, "sockcreate"))
5211                 tsec->sockcreate_sid = sid;
5212         else if (!strcmp(name, "current")) {
5213                 struct av_decision avd;
5214
5215                 if (sid == 0)
5216                         return -EINVAL;
5217
5218                 /* Only allow single threaded processes to change context */
5219                 if (atomic_read(&p->mm->mm_users) != 1) {
5220                         struct task_struct *g, *t;
5221                         struct mm_struct *mm = p->mm;
5222                         read_lock(&tasklist_lock);
5223                         do_each_thread(g, t) {
5224                                 if (t->mm == mm && t != p) {
5225                                         read_unlock(&tasklist_lock);
5226                                         return -EPERM;
5227                                 }
5228                         } while_each_thread(g, t);
5229                         read_unlock(&tasklist_lock);
5230                 }
5231
5232                 /* Check permissions for the transition. */
5233                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5234                                      PROCESS__DYNTRANSITION, NULL);
5235                 if (error)
5236                         return error;
5237
5238                 /* Check for ptracing, and update the task SID if ok.
5239                    Otherwise, leave SID unchanged and fail. */
5240                 task_lock(p);
5241                 rcu_read_lock();
5242                 tracer = tracehook_tracer_task(p);
5243                 if (tracer != NULL) {
5244                         struct task_security_struct *ptsec = tracer->security;
5245                         u32 ptsid = ptsec->sid;
5246                         rcu_read_unlock();
5247                         error = avc_has_perm_noaudit(ptsid, sid,
5248                                                      SECCLASS_PROCESS,
5249                                                      PROCESS__PTRACE, 0, &avd);
5250                         if (!error)
5251                                 tsec->sid = sid;
5252                         task_unlock(p);
5253                         avc_audit(ptsid, sid, SECCLASS_PROCESS,
5254                                   PROCESS__PTRACE, &avd, error, NULL);
5255                         if (error)
5256                                 return error;
5257                 } else {
5258                         rcu_read_unlock();
5259                         tsec->sid = sid;
5260                         task_unlock(p);
5261                 }
5262         } else
5263                 return -EINVAL;
5264
5265         return size;
5266 }
5267
5268 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5269 {
5270         return security_sid_to_context(secid, secdata, seclen);
5271 }
5272
5273 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5274 {
5275         return security_context_to_sid(secdata, seclen, secid);
5276 }
5277
5278 static void selinux_release_secctx(char *secdata, u32 seclen)
5279 {
5280         kfree(secdata);
5281 }
5282
5283 #ifdef CONFIG_KEYS
5284
5285 static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
5286                              unsigned long flags)
5287 {
5288         struct task_security_struct *tsec = tsk->security;
5289         struct key_security_struct *ksec;
5290
5291         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5292         if (!ksec)
5293                 return -ENOMEM;
5294
5295         if (tsec->keycreate_sid)
5296                 ksec->sid = tsec->keycreate_sid;
5297         else
5298                 ksec->sid = tsec->sid;
5299         k->security = ksec;
5300
5301         return 0;
5302 }
5303
5304 static void selinux_key_free(struct key *k)
5305 {
5306         struct key_security_struct *ksec = k->security;
5307
5308         k->security = NULL;
5309         kfree(ksec);
5310 }
5311
5312 static int selinux_key_permission(key_ref_t key_ref,
5313                             struct task_struct *ctx,
5314                             key_perm_t perm)
5315 {
5316         struct key *key;
5317         struct task_security_struct *tsec;
5318         struct key_security_struct *ksec;
5319
5320         key = key_ref_to_ptr(key_ref);
5321
5322         tsec = ctx->security;
5323         ksec = key->security;
5324
5325         /* if no specific permissions are requested, we skip the
5326            permission check. No serious, additional covert channels
5327            appear to be created. */
5328         if (perm == 0)
5329                 return 0;
5330
5331         return avc_has_perm(tsec->sid, ksec->sid,
5332                             SECCLASS_KEY, perm, NULL);
5333 }
5334
5335 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5336 {
5337         struct key_security_struct *ksec = key->security;
5338         char *context = NULL;
5339         unsigned len;
5340         int rc;
5341
5342         rc = security_sid_to_context(ksec->sid, &context, &len);
5343         if (!rc)
5344                 rc = len;
5345         *_buffer = context;
5346         return rc;
5347 }
5348
5349 #endif
5350
5351 static struct security_operations selinux_ops = {
5352         .name =                         "selinux",
5353
5354         .ptrace_may_access =            selinux_ptrace_may_access,
5355         .ptrace_traceme =               selinux_ptrace_traceme,
5356         .capget =                       selinux_capget,
5357         .capset_check =                 selinux_capset_check,
5358         .capset_set =                   selinux_capset_set,
5359         .sysctl =                       selinux_sysctl,
5360         .capable =                      selinux_capable,
5361         .quotactl =                     selinux_quotactl,
5362         .quota_on =                     selinux_quota_on,
5363         .syslog =                       selinux_syslog,
5364         .vm_enough_memory =             selinux_vm_enough_memory,
5365
5366         .netlink_send =                 selinux_netlink_send,
5367         .netlink_recv =                 selinux_netlink_recv,
5368
5369         .bprm_alloc_security =          selinux_bprm_alloc_security,
5370         .bprm_free_security =           selinux_bprm_free_security,
5371         .bprm_apply_creds =             selinux_bprm_apply_creds,
5372         .bprm_post_apply_creds =        selinux_bprm_post_apply_creds,
5373         .bprm_set_security =            selinux_bprm_set_security,
5374         .bprm_check_security =          selinux_bprm_check_security,
5375         .bprm_secureexec =              selinux_bprm_secureexec,
5376
5377         .sb_alloc_security =            selinux_sb_alloc_security,
5378         .sb_free_security =             selinux_sb_free_security,
5379         .sb_copy_data =                 selinux_sb_copy_data,
5380         .sb_kern_mount =                selinux_sb_kern_mount,
5381         .sb_show_options =              selinux_sb_show_options,
5382         .sb_statfs =                    selinux_sb_statfs,
5383         .sb_mount =                     selinux_mount,
5384         .sb_umount =                    selinux_umount,
5385         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5386         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5387         .sb_parse_opts_str =            selinux_parse_opts_str,
5388
5389
5390         .inode_alloc_security =         selinux_inode_alloc_security,
5391         .inode_free_security =          selinux_inode_free_security,
5392         .inode_init_security =          selinux_inode_init_security,
5393         .inode_create =                 selinux_inode_create,
5394         .inode_link =                   selinux_inode_link,
5395         .inode_unlink =                 selinux_inode_unlink,
5396         .inode_symlink =                selinux_inode_symlink,
5397         .inode_mkdir =                  selinux_inode_mkdir,
5398         .inode_rmdir =                  selinux_inode_rmdir,
5399         .inode_mknod =                  selinux_inode_mknod,
5400         .inode_rename =                 selinux_inode_rename,
5401         .inode_readlink =               selinux_inode_readlink,
5402         .inode_follow_link =            selinux_inode_follow_link,
5403         .inode_permission =             selinux_inode_permission,
5404         .inode_setattr =                selinux_inode_setattr,
5405         .inode_getattr =                selinux_inode_getattr,
5406         .inode_setxattr =               selinux_inode_setxattr,
5407         .inode_post_setxattr =          selinux_inode_post_setxattr,
5408         .inode_getxattr =               selinux_inode_getxattr,
5409         .inode_listxattr =              selinux_inode_listxattr,
5410         .inode_removexattr =            selinux_inode_removexattr,
5411         .inode_getsecurity =            selinux_inode_getsecurity,
5412         .inode_setsecurity =            selinux_inode_setsecurity,
5413         .inode_listsecurity =           selinux_inode_listsecurity,
5414         .inode_need_killpriv =          selinux_inode_need_killpriv,
5415         .inode_killpriv =               selinux_inode_killpriv,
5416         .inode_getsecid =               selinux_inode_getsecid,
5417
5418         .file_permission =              selinux_file_permission,
5419         .file_alloc_security =          selinux_file_alloc_security,
5420         .file_free_security =           selinux_file_free_security,
5421         .file_ioctl =                   selinux_file_ioctl,
5422         .file_mmap =                    selinux_file_mmap,
5423         .file_mprotect =                selinux_file_mprotect,
5424         .file_lock =                    selinux_file_lock,
5425         .file_fcntl =                   selinux_file_fcntl,
5426         .file_set_fowner =              selinux_file_set_fowner,
5427         .file_send_sigiotask =          selinux_file_send_sigiotask,
5428         .file_receive =                 selinux_file_receive,
5429
5430         .dentry_open =                  selinux_dentry_open,
5431
5432         .task_create =                  selinux_task_create,
5433         .task_alloc_security =          selinux_task_alloc_security,
5434         .task_free_security =           selinux_task_free_security,
5435         .task_setuid =                  selinux_task_setuid,
5436         .task_post_setuid =             selinux_task_post_setuid,
5437         .task_setgid =                  selinux_task_setgid,
5438         .task_setpgid =                 selinux_task_setpgid,
5439         .task_getpgid =                 selinux_task_getpgid,
5440         .task_getsid =                  selinux_task_getsid,
5441         .task_getsecid =                selinux_task_getsecid,
5442         .task_setgroups =               selinux_task_setgroups,
5443         .task_setnice =                 selinux_task_setnice,
5444         .task_setioprio =               selinux_task_setioprio,
5445         .task_getioprio =               selinux_task_getioprio,
5446         .task_setrlimit =               selinux_task_setrlimit,
5447         .task_setscheduler =            selinux_task_setscheduler,
5448         .task_getscheduler =            selinux_task_getscheduler,
5449         .task_movememory =              selinux_task_movememory,
5450         .task_kill =                    selinux_task_kill,
5451         .task_wait =                    selinux_task_wait,
5452         .task_prctl =                   selinux_task_prctl,
5453         .task_reparent_to_init =        selinux_task_reparent_to_init,
5454         .task_to_inode =                selinux_task_to_inode,
5455
5456         .ipc_permission =               selinux_ipc_permission,
5457         .ipc_getsecid =                 selinux_ipc_getsecid,
5458
5459         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5460         .msg_msg_free_security =        selinux_msg_msg_free_security,
5461
5462         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5463         .msg_queue_free_security =      selinux_msg_queue_free_security,
5464         .msg_queue_associate =          selinux_msg_queue_associate,
5465         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5466         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5467         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5468
5469         .shm_alloc_security =           selinux_shm_alloc_security,
5470         .shm_free_security =            selinux_shm_free_security,
5471         .shm_associate =                selinux_shm_associate,
5472         .shm_shmctl =                   selinux_shm_shmctl,
5473         .shm_shmat =                    selinux_shm_shmat,
5474
5475         .sem_alloc_security =           selinux_sem_alloc_security,
5476         .sem_free_security =            selinux_sem_free_security,
5477         .sem_associate =                selinux_sem_associate,
5478         .sem_semctl =                   selinux_sem_semctl,
5479         .sem_semop =                    selinux_sem_semop,
5480
5481         .d_instantiate =                selinux_d_instantiate,
5482
5483         .getprocattr =                  selinux_getprocattr,
5484         .setprocattr =                  selinux_setprocattr,
5485
5486         .secid_to_secctx =              selinux_secid_to_secctx,
5487         .secctx_to_secid =              selinux_secctx_to_secid,
5488         .release_secctx =               selinux_release_secctx,
5489
5490         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5491         .unix_may_send =                selinux_socket_unix_may_send,
5492
5493         .socket_create =                selinux_socket_create,
5494         .socket_post_create =           selinux_socket_post_create,
5495         .socket_bind =                  selinux_socket_bind,
5496         .socket_connect =               selinux_socket_connect,
5497         .socket_listen =                selinux_socket_listen,
5498         .socket_accept =                selinux_socket_accept,
5499         .socket_sendmsg =               selinux_socket_sendmsg,
5500         .socket_recvmsg =               selinux_socket_recvmsg,
5501         .socket_getsockname =           selinux_socket_getsockname,
5502         .socket_getpeername =           selinux_socket_getpeername,
5503         .socket_getsockopt =            selinux_socket_getsockopt,
5504         .socket_setsockopt =            selinux_socket_setsockopt,
5505         .socket_shutdown =              selinux_socket_shutdown,
5506         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5507         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5508         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5509         .sk_alloc_security =            selinux_sk_alloc_security,
5510         .sk_free_security =             selinux_sk_free_security,
5511         .sk_clone_security =            selinux_sk_clone_security,
5512         .sk_getsecid =                  selinux_sk_getsecid,
5513         .sock_graft =                   selinux_sock_graft,
5514         .inet_conn_request =            selinux_inet_conn_request,
5515         .inet_csk_clone =               selinux_inet_csk_clone,
5516         .inet_conn_established =        selinux_inet_conn_established,
5517         .req_classify_flow =            selinux_req_classify_flow,
5518
5519 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5520         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5521         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5522         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5523         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5524         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5525         .xfrm_state_free_security =     selinux_xfrm_state_free,
5526         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5527         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5528         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5529         .xfrm_decode_session =          selinux_xfrm_decode_session,
5530 #endif
5531
5532 #ifdef CONFIG_KEYS
5533         .key_alloc =                    selinux_key_alloc,
5534         .key_free =                     selinux_key_free,
5535         .key_permission =               selinux_key_permission,
5536         .key_getsecurity =              selinux_key_getsecurity,
5537 #endif
5538
5539 #ifdef CONFIG_AUDIT
5540         .audit_rule_init =              selinux_audit_rule_init,
5541         .audit_rule_known =             selinux_audit_rule_known,
5542         .audit_rule_match =             selinux_audit_rule_match,
5543         .audit_rule_free =              selinux_audit_rule_free,
5544 #endif
5545 };
5546
5547 static __init int selinux_init(void)
5548 {
5549         struct task_security_struct *tsec;
5550
5551         if (!security_module_enable(&selinux_ops)) {
5552                 selinux_enabled = 0;
5553                 return 0;
5554         }
5555
5556         if (!selinux_enabled) {
5557                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5558                 return 0;
5559         }
5560
5561         printk(KERN_INFO "SELinux:  Initializing.\n");
5562
5563         /* Set the security state for the initial task. */
5564         if (task_alloc_security(current))
5565                 panic("SELinux:  Failed to initialize initial task.\n");
5566         tsec = current->security;
5567         tsec->osid = tsec->sid = SECINITSID_KERNEL;
5568
5569         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5570                                             sizeof(struct inode_security_struct),
5571                                             0, SLAB_PANIC, NULL);
5572         avc_init();
5573
5574         secondary_ops = security_ops;
5575         if (!secondary_ops)
5576                 panic("SELinux: No initial security operations\n");
5577         if (register_security(&selinux_ops))
5578                 panic("SELinux: Unable to register with kernel.\n");
5579
5580         if (selinux_enforcing)
5581                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5582         else
5583                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5584
5585         return 0;
5586 }
5587
5588 void selinux_complete_init(void)
5589 {
5590         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5591
5592         /* Set up any superblocks initialized prior to the policy load. */
5593         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5594         spin_lock(&sb_lock);
5595         spin_lock(&sb_security_lock);
5596 next_sb:
5597         if (!list_empty(&superblock_security_head)) {
5598                 struct superblock_security_struct *sbsec =
5599                                 list_entry(superblock_security_head.next,
5600                                            struct superblock_security_struct,
5601                                            list);
5602                 struct super_block *sb = sbsec->sb;
5603                 sb->s_count++;
5604                 spin_unlock(&sb_security_lock);
5605                 spin_unlock(&sb_lock);
5606                 down_read(&sb->s_umount);
5607                 if (sb->s_root)
5608                         superblock_doinit(sb, NULL);
5609                 drop_super(sb);
5610                 spin_lock(&sb_lock);
5611                 spin_lock(&sb_security_lock);
5612                 list_del_init(&sbsec->list);
5613                 goto next_sb;
5614         }
5615         spin_unlock(&sb_security_lock);
5616         spin_unlock(&sb_lock);
5617 }
5618
5619 /* SELinux requires early initialization in order to label
5620    all processes and objects when they are created. */
5621 security_initcall(selinux_init);
5622
5623 #if defined(CONFIG_NETFILTER)
5624
5625 static struct nf_hook_ops selinux_ipv4_ops[] = {
5626         {
5627                 .hook =         selinux_ipv4_postroute,
5628                 .owner =        THIS_MODULE,
5629                 .pf =           PF_INET,
5630                 .hooknum =      NF_INET_POST_ROUTING,
5631                 .priority =     NF_IP_PRI_SELINUX_LAST,
5632         },
5633         {
5634                 .hook =         selinux_ipv4_forward,
5635                 .owner =        THIS_MODULE,
5636                 .pf =           PF_INET,
5637                 .hooknum =      NF_INET_FORWARD,
5638                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5639         }
5640 };
5641
5642 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5643
5644 static struct nf_hook_ops selinux_ipv6_ops[] = {
5645         {
5646                 .hook =         selinux_ipv6_postroute,
5647                 .owner =        THIS_MODULE,
5648                 .pf =           PF_INET6,
5649                 .hooknum =      NF_INET_POST_ROUTING,
5650                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5651         },
5652         {
5653                 .hook =         selinux_ipv6_forward,
5654                 .owner =        THIS_MODULE,
5655                 .pf =           PF_INET6,
5656                 .hooknum =      NF_INET_FORWARD,
5657                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5658         }
5659 };
5660
5661 #endif  /* IPV6 */
5662
5663 static int __init selinux_nf_ip_init(void)
5664 {
5665         int err = 0;
5666
5667         if (!selinux_enabled)
5668                 goto out;
5669
5670         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5671
5672         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5673         if (err)
5674                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5675
5676 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5677         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5678         if (err)
5679                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5680 #endif  /* IPV6 */
5681
5682 out:
5683         return err;
5684 }
5685
5686 __initcall(selinux_nf_ip_init);
5687
5688 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5689 static void selinux_nf_ip_exit(void)
5690 {
5691         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5692
5693         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5694 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5695         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5696 #endif  /* IPV6 */
5697 }
5698 #endif
5699
5700 #else /* CONFIG_NETFILTER */
5701
5702 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5703 #define selinux_nf_ip_exit()
5704 #endif
5705
5706 #endif /* CONFIG_NETFILTER */
5707
5708 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5709 static int selinux_disabled;
5710
5711 int selinux_disable(void)
5712 {
5713         extern void exit_sel_fs(void);
5714
5715         if (ss_initialized) {
5716                 /* Not permitted after initial policy load. */
5717                 return -EINVAL;
5718         }
5719
5720         if (selinux_disabled) {
5721                 /* Only do this once. */
5722                 return -EINVAL;
5723         }
5724
5725         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5726
5727         selinux_disabled = 1;
5728         selinux_enabled = 0;
5729
5730         /* Reset security_ops to the secondary module, dummy or capability. */
5731         security_ops = secondary_ops;
5732
5733         /* Unregister netfilter hooks. */
5734         selinux_nf_ip_exit();
5735
5736         /* Unregister selinuxfs. */
5737         exit_sel_fs();
5738
5739         return 0;
5740 }
5741 #endif