tty: Redo current tty locking
[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
79 #include "avc.h"
80 #include "objsec.h"
81 #include "netif.h"
82 #include "netnode.h"
83 #include "netport.h"
84 #include "xfrm.h"
85 #include "netlabel.h"
86 #include "audit.h"
87
88 #define XATTR_SELINUX_SUFFIX "selinux"
89 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
90
91 #define NUM_SEL_MNT_OPTS 4
92
93 extern unsigned int policydb_loaded_version;
94 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
95 extern int selinux_compat_net;
96 extern struct security_operations *security_ops;
97
98 /* SECMARK reference count */
99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 int selinux_enforcing;
103
104 static int __init enforcing_setup(char *str)
105 {
106         unsigned long enforcing;
107         if (!strict_strtoul(str, 0, &enforcing))
108                 selinux_enforcing = enforcing ? 1 : 0;
109         return 1;
110 }
111 __setup("enforcing=", enforcing_setup);
112 #endif
113
114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117 static int __init selinux_enabled_setup(char *str)
118 {
119         unsigned long enabled;
120         if (!strict_strtoul(str, 0, &enabled))
121                 selinux_enabled = enabled ? 1 : 0;
122         return 1;
123 }
124 __setup("selinux=", selinux_enabled_setup);
125 #else
126 int selinux_enabled = 1;
127 #endif
128
129
130 /*
131  * Minimal support for a secondary security module,
132  * just to allow the use of the capability module.
133  */
134 static struct security_operations *secondary_ops;
135
136 /* Lists of inode and superblock security structures initialized
137    before the policy was loaded. */
138 static LIST_HEAD(superblock_security_head);
139 static DEFINE_SPINLOCK(sb_security_lock);
140
141 static struct kmem_cache *sel_inode_cache;
142
143 /**
144  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
145  *
146  * Description:
147  * This function checks the SECMARK reference counter to see if any SECMARK
148  * targets are currently configured, if the reference counter is greater than
149  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
150  * enabled, false (0) if SECMARK is disabled.
151  *
152  */
153 static int selinux_secmark_enabled(void)
154 {
155         return (atomic_read(&selinux_secmark_refcount) > 0);
156 }
157
158 /* Allocate and free functions for each kind of security blob. */
159
160 static int task_alloc_security(struct task_struct *task)
161 {
162         struct task_security_struct *tsec;
163
164         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
165         if (!tsec)
166                 return -ENOMEM;
167
168         tsec->osid = tsec->sid = SECINITSID_UNLABELED;
169         task->security = tsec;
170
171         return 0;
172 }
173
174 static void task_free_security(struct task_struct *task)
175 {
176         struct task_security_struct *tsec = task->security;
177         task->security = NULL;
178         kfree(tsec);
179 }
180
181 static int inode_alloc_security(struct inode *inode)
182 {
183         struct task_security_struct *tsec = current->security;
184         struct inode_security_struct *isec;
185
186         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
187         if (!isec)
188                 return -ENOMEM;
189
190         mutex_init(&isec->lock);
191         INIT_LIST_HEAD(&isec->list);
192         isec->inode = inode;
193         isec->sid = SECINITSID_UNLABELED;
194         isec->sclass = SECCLASS_FILE;
195         isec->task_sid = tsec->sid;
196         inode->i_security = isec;
197
198         return 0;
199 }
200
201 static void inode_free_security(struct inode *inode)
202 {
203         struct inode_security_struct *isec = inode->i_security;
204         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
205
206         spin_lock(&sbsec->isec_lock);
207         if (!list_empty(&isec->list))
208                 list_del_init(&isec->list);
209         spin_unlock(&sbsec->isec_lock);
210
211         inode->i_security = NULL;
212         kmem_cache_free(sel_inode_cache, isec);
213 }
214
215 static int file_alloc_security(struct file *file)
216 {
217         struct task_security_struct *tsec = current->security;
218         struct file_security_struct *fsec;
219
220         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
221         if (!fsec)
222                 return -ENOMEM;
223
224         fsec->sid = tsec->sid;
225         fsec->fown_sid = tsec->sid;
226         file->f_security = fsec;
227
228         return 0;
229 }
230
231 static void file_free_security(struct file *file)
232 {
233         struct file_security_struct *fsec = file->f_security;
234         file->f_security = NULL;
235         kfree(fsec);
236 }
237
238 static int superblock_alloc_security(struct super_block *sb)
239 {
240         struct superblock_security_struct *sbsec;
241
242         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
243         if (!sbsec)
244                 return -ENOMEM;
245
246         mutex_init(&sbsec->lock);
247         INIT_LIST_HEAD(&sbsec->list);
248         INIT_LIST_HEAD(&sbsec->isec_head);
249         spin_lock_init(&sbsec->isec_lock);
250         sbsec->sb = sb;
251         sbsec->sid = SECINITSID_UNLABELED;
252         sbsec->def_sid = SECINITSID_FILE;
253         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
254         sb->s_security = sbsec;
255
256         return 0;
257 }
258
259 static void superblock_free_security(struct super_block *sb)
260 {
261         struct superblock_security_struct *sbsec = sb->s_security;
262
263         spin_lock(&sb_security_lock);
264         if (!list_empty(&sbsec->list))
265                 list_del_init(&sbsec->list);
266         spin_unlock(&sb_security_lock);
267
268         sb->s_security = NULL;
269         kfree(sbsec);
270 }
271
272 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
273 {
274         struct sk_security_struct *ssec;
275
276         ssec = kzalloc(sizeof(*ssec), priority);
277         if (!ssec)
278                 return -ENOMEM;
279
280         ssec->peer_sid = SECINITSID_UNLABELED;
281         ssec->sid = SECINITSID_UNLABELED;
282         sk->sk_security = ssec;
283
284         selinux_netlbl_sk_security_reset(ssec, family);
285
286         return 0;
287 }
288
289 static void sk_free_security(struct sock *sk)
290 {
291         struct sk_security_struct *ssec = sk->sk_security;
292
293         sk->sk_security = NULL;
294         kfree(ssec);
295 }
296
297 /* The security server must be initialized before
298    any labeling or access decisions can be provided. */
299 extern int ss_initialized;
300
301 /* The file system's label must be initialized prior to use. */
302
303 static char *labeling_behaviors[6] = {
304         "uses xattr",
305         "uses transition SIDs",
306         "uses task SIDs",
307         "uses genfs_contexts",
308         "not configured for labeling",
309         "uses mountpoint labeling",
310 };
311
312 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
313
314 static inline int inode_doinit(struct inode *inode)
315 {
316         return inode_doinit_with_dentry(inode, NULL);
317 }
318
319 enum {
320         Opt_error = -1,
321         Opt_context = 1,
322         Opt_fscontext = 2,
323         Opt_defcontext = 3,
324         Opt_rootcontext = 4,
325 };
326
327 static match_table_t tokens = {
328         {Opt_context, CONTEXT_STR "%s"},
329         {Opt_fscontext, FSCONTEXT_STR "%s"},
330         {Opt_defcontext, DEFCONTEXT_STR "%s"},
331         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
332         {Opt_error, NULL},
333 };
334
335 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
336
337 static int may_context_mount_sb_relabel(u32 sid,
338                         struct superblock_security_struct *sbsec,
339                         struct task_security_struct *tsec)
340 {
341         int rc;
342
343         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
344                           FILESYSTEM__RELABELFROM, NULL);
345         if (rc)
346                 return rc;
347
348         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
349                           FILESYSTEM__RELABELTO, NULL);
350         return rc;
351 }
352
353 static int may_context_mount_inode_relabel(u32 sid,
354                         struct superblock_security_struct *sbsec,
355                         struct task_security_struct *tsec)
356 {
357         int rc;
358         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
359                           FILESYSTEM__RELABELFROM, NULL);
360         if (rc)
361                 return rc;
362
363         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
364                           FILESYSTEM__ASSOCIATE, NULL);
365         return rc;
366 }
367
368 static int sb_finish_set_opts(struct super_block *sb)
369 {
370         struct superblock_security_struct *sbsec = sb->s_security;
371         struct dentry *root = sb->s_root;
372         struct inode *root_inode = root->d_inode;
373         int rc = 0;
374
375         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
376                 /* Make sure that the xattr handler exists and that no
377                    error other than -ENODATA is returned by getxattr on
378                    the root directory.  -ENODATA is ok, as this may be
379                    the first boot of the SELinux kernel before we have
380                    assigned xattr values to the filesystem. */
381                 if (!root_inode->i_op->getxattr) {
382                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
383                                "xattr support\n", sb->s_id, sb->s_type->name);
384                         rc = -EOPNOTSUPP;
385                         goto out;
386                 }
387                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
388                 if (rc < 0 && rc != -ENODATA) {
389                         if (rc == -EOPNOTSUPP)
390                                 printk(KERN_WARNING "SELinux: (dev %s, type "
391                                        "%s) has no security xattr handler\n",
392                                        sb->s_id, sb->s_type->name);
393                         else
394                                 printk(KERN_WARNING "SELinux: (dev %s, type "
395                                        "%s) getxattr errno %d\n", sb->s_id,
396                                        sb->s_type->name, -rc);
397                         goto out;
398                 }
399         }
400
401         sbsec->initialized = 1;
402
403         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
405                        sb->s_id, sb->s_type->name);
406         else
407                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
408                        sb->s_id, sb->s_type->name,
409                        labeling_behaviors[sbsec->behavior-1]);
410
411         /* Initialize the root inode. */
412         rc = inode_doinit_with_dentry(root_inode, root);
413
414         /* Initialize any other inodes associated with the superblock, e.g.
415            inodes created prior to initial policy load or inodes created
416            during get_sb by a pseudo filesystem that directly
417            populates itself. */
418         spin_lock(&sbsec->isec_lock);
419 next_inode:
420         if (!list_empty(&sbsec->isec_head)) {
421                 struct inode_security_struct *isec =
422                                 list_entry(sbsec->isec_head.next,
423                                            struct inode_security_struct, list);
424                 struct inode *inode = isec->inode;
425                 spin_unlock(&sbsec->isec_lock);
426                 inode = igrab(inode);
427                 if (inode) {
428                         if (!IS_PRIVATE(inode))
429                                 inode_doinit(inode);
430                         iput(inode);
431                 }
432                 spin_lock(&sbsec->isec_lock);
433                 list_del_init(&isec->list);
434                 goto next_inode;
435         }
436         spin_unlock(&sbsec->isec_lock);
437 out:
438         return rc;
439 }
440
441 /*
442  * This function should allow an FS to ask what it's mount security
443  * options were so it can use those later for submounts, displaying
444  * mount options, or whatever.
445  */
446 static int selinux_get_mnt_opts(const struct super_block *sb,
447                                 struct security_mnt_opts *opts)
448 {
449         int rc = 0, i;
450         struct superblock_security_struct *sbsec = sb->s_security;
451         char *context = NULL;
452         u32 len;
453         char tmp;
454
455         security_init_mnt_opts(opts);
456
457         if (!sbsec->initialized)
458                 return -EINVAL;
459
460         if (!ss_initialized)
461                 return -EINVAL;
462
463         /*
464          * if we ever use sbsec flags for anything other than tracking mount
465          * settings this is going to need a mask
466          */
467         tmp = sbsec->flags;
468         /* count the number of mount options for this sb */
469         for (i = 0; i < 8; i++) {
470                 if (tmp & 0x01)
471                         opts->num_mnt_opts++;
472                 tmp >>= 1;
473         }
474
475         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
476         if (!opts->mnt_opts) {
477                 rc = -ENOMEM;
478                 goto out_free;
479         }
480
481         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
482         if (!opts->mnt_opts_flags) {
483                 rc = -ENOMEM;
484                 goto out_free;
485         }
486
487         i = 0;
488         if (sbsec->flags & FSCONTEXT_MNT) {
489                 rc = security_sid_to_context(sbsec->sid, &context, &len);
490                 if (rc)
491                         goto out_free;
492                 opts->mnt_opts[i] = context;
493                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
494         }
495         if (sbsec->flags & CONTEXT_MNT) {
496                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
497                 if (rc)
498                         goto out_free;
499                 opts->mnt_opts[i] = context;
500                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
501         }
502         if (sbsec->flags & DEFCONTEXT_MNT) {
503                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
504                 if (rc)
505                         goto out_free;
506                 opts->mnt_opts[i] = context;
507                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
508         }
509         if (sbsec->flags & ROOTCONTEXT_MNT) {
510                 struct inode *root = sbsec->sb->s_root->d_inode;
511                 struct inode_security_struct *isec = root->i_security;
512
513                 rc = security_sid_to_context(isec->sid, &context, &len);
514                 if (rc)
515                         goto out_free;
516                 opts->mnt_opts[i] = context;
517                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
518         }
519
520         BUG_ON(i != opts->num_mnt_opts);
521
522         return 0;
523
524 out_free:
525         security_free_mnt_opts(opts);
526         return rc;
527 }
528
529 static int bad_option(struct superblock_security_struct *sbsec, char flag,
530                       u32 old_sid, u32 new_sid)
531 {
532         /* check if the old mount command had the same options */
533         if (sbsec->initialized)
534                 if (!(sbsec->flags & flag) ||
535                     (old_sid != new_sid))
536                         return 1;
537
538         /* check if we were passed the same options twice,
539          * aka someone passed context=a,context=b
540          */
541         if (!sbsec->initialized)
542                 if (sbsec->flags & flag)
543                         return 1;
544         return 0;
545 }
546
547 /*
548  * Allow filesystems with binary mount data to explicitly set mount point
549  * labeling information.
550  */
551 static int selinux_set_mnt_opts(struct super_block *sb,
552                                 struct security_mnt_opts *opts)
553 {
554         int rc = 0, i;
555         struct task_security_struct *tsec = current->security;
556         struct superblock_security_struct *sbsec = sb->s_security;
557         const char *name = sb->s_type->name;
558         struct inode *inode = sbsec->sb->s_root->d_inode;
559         struct inode_security_struct *root_isec = inode->i_security;
560         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
561         u32 defcontext_sid = 0;
562         char **mount_options = opts->mnt_opts;
563         int *flags = opts->mnt_opts_flags;
564         int num_opts = opts->num_mnt_opts;
565
566         mutex_lock(&sbsec->lock);
567
568         if (!ss_initialized) {
569                 if (!num_opts) {
570                         /* Defer initialization until selinux_complete_init,
571                            after the initial policy is loaded and the security
572                            server is ready to handle calls. */
573                         spin_lock(&sb_security_lock);
574                         if (list_empty(&sbsec->list))
575                                 list_add(&sbsec->list, &superblock_security_head);
576                         spin_unlock(&sb_security_lock);
577                         goto out;
578                 }
579                 rc = -EINVAL;
580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581                         "before the security server is initialized\n");
582                 goto out;
583         }
584
585         /*
586          * Binary mount data FS will come through this function twice.  Once
587          * from an explicit call and once from the generic calls from the vfs.
588          * Since the generic VFS calls will not contain any security mount data
589          * we need to skip the double mount verification.
590          *
591          * This does open a hole in which we will not notice if the first
592          * mount using this sb set explict options and a second mount using
593          * this sb does not set any security options.  (The first options
594          * will be used for both mounts)
595          */
596         if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597             && (num_opts == 0))
598                 goto out;
599
600         /*
601          * parse the mount options, check if they are valid sids.
602          * also check if someone is trying to mount the same sb more
603          * than once with different security options.
604          */
605         for (i = 0; i < num_opts; i++) {
606                 u32 sid;
607                 rc = security_context_to_sid(mount_options[i],
608                                              strlen(mount_options[i]), &sid);
609                 if (rc) {
610                         printk(KERN_WARNING "SELinux: security_context_to_sid"
611                                "(%s) failed for (dev %s, type %s) errno=%d\n",
612                                mount_options[i], sb->s_id, name, rc);
613                         goto out;
614                 }
615                 switch (flags[i]) {
616                 case FSCONTEXT_MNT:
617                         fscontext_sid = sid;
618
619                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
620                                         fscontext_sid))
621                                 goto out_double_mount;
622
623                         sbsec->flags |= FSCONTEXT_MNT;
624                         break;
625                 case CONTEXT_MNT:
626                         context_sid = sid;
627
628                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
629                                         context_sid))
630                                 goto out_double_mount;
631
632                         sbsec->flags |= CONTEXT_MNT;
633                         break;
634                 case ROOTCONTEXT_MNT:
635                         rootcontext_sid = sid;
636
637                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
638                                         rootcontext_sid))
639                                 goto out_double_mount;
640
641                         sbsec->flags |= ROOTCONTEXT_MNT;
642
643                         break;
644                 case DEFCONTEXT_MNT:
645                         defcontext_sid = sid;
646
647                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
648                                         defcontext_sid))
649                                 goto out_double_mount;
650
651                         sbsec->flags |= DEFCONTEXT_MNT;
652
653                         break;
654                 default:
655                         rc = -EINVAL;
656                         goto out;
657                 }
658         }
659
660         if (sbsec->initialized) {
661                 /* previously mounted with options, but not on this attempt? */
662                 if (sbsec->flags && !num_opts)
663                         goto out_double_mount;
664                 rc = 0;
665                 goto out;
666         }
667
668         if (strcmp(sb->s_type->name, "proc") == 0)
669                 sbsec->proc = 1;
670
671         /* Determine the labeling behavior to use for this filesystem type. */
672         rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
673         if (rc) {
674                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
675                        __func__, sb->s_type->name, rc);
676                 goto out;
677         }
678
679         /* sets the context of the superblock for the fs being mounted. */
680         if (fscontext_sid) {
681
682                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec);
683                 if (rc)
684                         goto out;
685
686                 sbsec->sid = fscontext_sid;
687         }
688
689         /*
690          * Switch to using mount point labeling behavior.
691          * sets the label used on all file below the mountpoint, and will set
692          * the superblock context if not already set.
693          */
694         if (context_sid) {
695                 if (!fscontext_sid) {
696                         rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec);
697                         if (rc)
698                                 goto out;
699                         sbsec->sid = context_sid;
700                 } else {
701                         rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec);
702                         if (rc)
703                                 goto out;
704                 }
705                 if (!rootcontext_sid)
706                         rootcontext_sid = context_sid;
707
708                 sbsec->mntpoint_sid = context_sid;
709                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
710         }
711
712         if (rootcontext_sid) {
713                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec);
714                 if (rc)
715                         goto out;
716
717                 root_isec->sid = rootcontext_sid;
718                 root_isec->initialized = 1;
719         }
720
721         if (defcontext_sid) {
722                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
723                         rc = -EINVAL;
724                         printk(KERN_WARNING "SELinux: defcontext option is "
725                                "invalid for this filesystem type\n");
726                         goto out;
727                 }
728
729                 if (defcontext_sid != sbsec->def_sid) {
730                         rc = may_context_mount_inode_relabel(defcontext_sid,
731                                                              sbsec, tsec);
732                         if (rc)
733                                 goto out;
734                 }
735
736                 sbsec->def_sid = defcontext_sid;
737         }
738
739         rc = sb_finish_set_opts(sb);
740 out:
741         mutex_unlock(&sbsec->lock);
742         return rc;
743 out_double_mount:
744         rc = -EINVAL;
745         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
746                "security settings for (dev %s, type %s)\n", sb->s_id, name);
747         goto out;
748 }
749
750 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
751                                         struct super_block *newsb)
752 {
753         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
754         struct superblock_security_struct *newsbsec = newsb->s_security;
755
756         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
757         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
758         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
759
760         /*
761          * if the parent was able to be mounted it clearly had no special lsm
762          * mount options.  thus we can safely put this sb on the list and deal
763          * with it later
764          */
765         if (!ss_initialized) {
766                 spin_lock(&sb_security_lock);
767                 if (list_empty(&newsbsec->list))
768                         list_add(&newsbsec->list, &superblock_security_head);
769                 spin_unlock(&sb_security_lock);
770                 return;
771         }
772
773         /* how can we clone if the old one wasn't set up?? */
774         BUG_ON(!oldsbsec->initialized);
775
776         /* if fs is reusing a sb, just let its options stand... */
777         if (newsbsec->initialized)
778                 return;
779
780         mutex_lock(&newsbsec->lock);
781
782         newsbsec->flags = oldsbsec->flags;
783
784         newsbsec->sid = oldsbsec->sid;
785         newsbsec->def_sid = oldsbsec->def_sid;
786         newsbsec->behavior = oldsbsec->behavior;
787
788         if (set_context) {
789                 u32 sid = oldsbsec->mntpoint_sid;
790
791                 if (!set_fscontext)
792                         newsbsec->sid = sid;
793                 if (!set_rootcontext) {
794                         struct inode *newinode = newsb->s_root->d_inode;
795                         struct inode_security_struct *newisec = newinode->i_security;
796                         newisec->sid = sid;
797                 }
798                 newsbsec->mntpoint_sid = sid;
799         }
800         if (set_rootcontext) {
801                 const struct inode *oldinode = oldsb->s_root->d_inode;
802                 const struct inode_security_struct *oldisec = oldinode->i_security;
803                 struct inode *newinode = newsb->s_root->d_inode;
804                 struct inode_security_struct *newisec = newinode->i_security;
805
806                 newisec->sid = oldisec->sid;
807         }
808
809         sb_finish_set_opts(newsb);
810         mutex_unlock(&newsbsec->lock);
811 }
812
813 static int selinux_parse_opts_str(char *options,
814                                   struct security_mnt_opts *opts)
815 {
816         char *p;
817         char *context = NULL, *defcontext = NULL;
818         char *fscontext = NULL, *rootcontext = NULL;
819         int rc, num_mnt_opts = 0;
820
821         opts->num_mnt_opts = 0;
822
823         /* Standard string-based options. */
824         while ((p = strsep(&options, "|")) != NULL) {
825                 int token;
826                 substring_t args[MAX_OPT_ARGS];
827
828                 if (!*p)
829                         continue;
830
831                 token = match_token(p, tokens, args);
832
833                 switch (token) {
834                 case Opt_context:
835                         if (context || defcontext) {
836                                 rc = -EINVAL;
837                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
838                                 goto out_err;
839                         }
840                         context = match_strdup(&args[0]);
841                         if (!context) {
842                                 rc = -ENOMEM;
843                                 goto out_err;
844                         }
845                         break;
846
847                 case Opt_fscontext:
848                         if (fscontext) {
849                                 rc = -EINVAL;
850                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
851                                 goto out_err;
852                         }
853                         fscontext = match_strdup(&args[0]);
854                         if (!fscontext) {
855                                 rc = -ENOMEM;
856                                 goto out_err;
857                         }
858                         break;
859
860                 case Opt_rootcontext:
861                         if (rootcontext) {
862                                 rc = -EINVAL;
863                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
864                                 goto out_err;
865                         }
866                         rootcontext = match_strdup(&args[0]);
867                         if (!rootcontext) {
868                                 rc = -ENOMEM;
869                                 goto out_err;
870                         }
871                         break;
872
873                 case Opt_defcontext:
874                         if (context || defcontext) {
875                                 rc = -EINVAL;
876                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
877                                 goto out_err;
878                         }
879                         defcontext = match_strdup(&args[0]);
880                         if (!defcontext) {
881                                 rc = -ENOMEM;
882                                 goto out_err;
883                         }
884                         break;
885
886                 default:
887                         rc = -EINVAL;
888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
889                         goto out_err;
890
891                 }
892         }
893
894         rc = -ENOMEM;
895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896         if (!opts->mnt_opts)
897                 goto out_err;
898
899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900         if (!opts->mnt_opts_flags) {
901                 kfree(opts->mnt_opts);
902                 goto out_err;
903         }
904
905         if (fscontext) {
906                 opts->mnt_opts[num_mnt_opts] = fscontext;
907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908         }
909         if (context) {
910                 opts->mnt_opts[num_mnt_opts] = context;
911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912         }
913         if (rootcontext) {
914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916         }
917         if (defcontext) {
918                 opts->mnt_opts[num_mnt_opts] = defcontext;
919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920         }
921
922         opts->num_mnt_opts = num_mnt_opts;
923         return 0;
924
925 out_err:
926         kfree(context);
927         kfree(defcontext);
928         kfree(fscontext);
929         kfree(rootcontext);
930         return rc;
931 }
932 /*
933  * string mount options parsing and call set the sbsec
934  */
935 static int superblock_doinit(struct super_block *sb, void *data)
936 {
937         int rc = 0;
938         char *options = data;
939         struct security_mnt_opts opts;
940
941         security_init_mnt_opts(&opts);
942
943         if (!data)
944                 goto out;
945
946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948         rc = selinux_parse_opts_str(options, &opts);
949         if (rc)
950                 goto out_err;
951
952 out:
953         rc = selinux_set_mnt_opts(sb, &opts);
954
955 out_err:
956         security_free_mnt_opts(&opts);
957         return rc;
958 }
959
960 static void selinux_write_opts(struct seq_file *m,
961                                struct security_mnt_opts *opts)
962 {
963         int i;
964         char *prefix;
965
966         for (i = 0; i < opts->num_mnt_opts; i++) {
967                 char *has_comma = 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 && !S_ISLNK(inode->i_mode)) {
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         tty = get_current_tty();
2125         if (tty) {
2126                 file_list_lock();
2127                 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
2128                 if (file) {
2129                         /* Revalidate access to controlling tty.
2130                            Use inode_has_perm on the tty inode directly rather
2131                            than using file_has_perm, as this particular open
2132                            file may belong to another process and we are only
2133                            interested in the inode-based check here. */
2134                         struct inode *inode = file->f_path.dentry->d_inode;
2135                         if (inode_has_perm(current, inode,
2136                                            FILE__READ | FILE__WRITE, NULL)) {
2137                                 drop_tty = 1;
2138                         }
2139                 }
2140                 file_list_unlock();
2141                 tty_kref_put(tty);
2142         }
2143         /* Reset controlling tty. */
2144         if (drop_tty)
2145                 no_tty();
2146
2147         /* Revalidate access to inherited open files. */
2148
2149         AVC_AUDIT_DATA_INIT(&ad, FS);
2150
2151         spin_lock(&files->file_lock);
2152         for (;;) {
2153                 unsigned long set, i;
2154                 int fd;
2155
2156                 j++;
2157                 i = j * __NFDBITS;
2158                 fdt = files_fdtable(files);
2159                 if (i >= fdt->max_fds)
2160                         break;
2161                 set = fdt->open_fds->fds_bits[j];
2162                 if (!set)
2163                         continue;
2164                 spin_unlock(&files->file_lock);
2165                 for ( ; set ; i++, set >>= 1) {
2166                         if (set & 1) {
2167                                 file = fget(i);
2168                                 if (!file)
2169                                         continue;
2170                                 if (file_has_perm(current,
2171                                                   file,
2172                                                   file_to_av(file))) {
2173                                         sys_close(i);
2174                                         fd = get_unused_fd();
2175                                         if (fd != i) {
2176                                                 if (fd >= 0)
2177                                                         put_unused_fd(fd);
2178                                                 fput(file);
2179                                                 continue;
2180                                         }
2181                                         if (devnull) {
2182                                                 get_file(devnull);
2183                                         } else {
2184                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
2185                                                 if (IS_ERR(devnull)) {
2186                                                         devnull = NULL;
2187                                                         put_unused_fd(fd);
2188                                                         fput(file);
2189                                                         continue;
2190                                                 }
2191                                         }
2192                                         fd_install(fd, devnull);
2193                                 }
2194                                 fput(file);
2195                         }
2196                 }
2197                 spin_lock(&files->file_lock);
2198
2199         }
2200         spin_unlock(&files->file_lock);
2201 }
2202
2203 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
2204 {
2205         struct task_security_struct *tsec;
2206         struct bprm_security_struct *bsec;
2207         u32 sid;
2208         int rc;
2209
2210         secondary_ops->bprm_apply_creds(bprm, unsafe);
2211
2212         tsec = current->security;
2213
2214         bsec = bprm->security;
2215         sid = bsec->sid;
2216
2217         tsec->osid = tsec->sid;
2218         bsec->unsafe = 0;
2219         if (tsec->sid != sid) {
2220                 /* Check for shared state.  If not ok, leave SID
2221                    unchanged and kill. */
2222                 if (unsafe & LSM_UNSAFE_SHARE) {
2223                         rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
2224                                         PROCESS__SHARE, NULL);
2225                         if (rc) {
2226                                 bsec->unsafe = 1;
2227                                 return;
2228                         }
2229                 }
2230
2231                 /* Check for ptracing, and update the task SID if ok.
2232                    Otherwise, leave SID unchanged and kill. */
2233                 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2234                         struct task_struct *tracer;
2235                         struct task_security_struct *sec;
2236                         u32 ptsid = 0;
2237
2238                         rcu_read_lock();
2239                         tracer = tracehook_tracer_task(current);
2240                         if (likely(tracer != NULL)) {
2241                                 sec = tracer->security;
2242                                 ptsid = sec->sid;
2243                         }
2244                         rcu_read_unlock();
2245
2246                         if (ptsid != 0) {
2247                                 rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
2248                                                   PROCESS__PTRACE, NULL);
2249                                 if (rc) {
2250                                         bsec->unsafe = 1;
2251                                         return;
2252                                 }
2253                         }
2254                 }
2255                 tsec->sid = sid;
2256         }
2257 }
2258
2259 /*
2260  * called after apply_creds without the task lock held
2261  */
2262 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
2263 {
2264         struct task_security_struct *tsec;
2265         struct rlimit *rlim, *initrlim;
2266         struct itimerval itimer;
2267         struct bprm_security_struct *bsec;
2268         int rc, i;
2269
2270         tsec = current->security;
2271         bsec = bprm->security;
2272
2273         if (bsec->unsafe) {
2274                 force_sig_specific(SIGKILL, current);
2275                 return;
2276         }
2277         if (tsec->osid == tsec->sid)
2278                 return;
2279
2280         /* Close files for which the new task SID is not authorized. */
2281         flush_unauthorized_files(current->files);
2282
2283         /* Check whether the new SID can inherit signal state
2284            from the old SID.  If not, clear itimers to avoid
2285            subsequent signal generation and flush and unblock
2286            signals. This must occur _after_ the task SID has
2287           been updated so that any kill done after the flush
2288           will be checked against the new SID. */
2289         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2290                           PROCESS__SIGINH, NULL);
2291         if (rc) {
2292                 memset(&itimer, 0, sizeof itimer);
2293                 for (i = 0; i < 3; i++)
2294                         do_setitimer(i, &itimer, NULL);
2295                 flush_signals(current);
2296                 spin_lock_irq(&current->sighand->siglock);
2297                 flush_signal_handlers(current, 1);
2298                 sigemptyset(&current->blocked);
2299                 recalc_sigpending();
2300                 spin_unlock_irq(&current->sighand->siglock);
2301         }
2302
2303         /* Always clear parent death signal on SID transitions. */
2304         current->pdeath_signal = 0;
2305
2306         /* Check whether the new SID can inherit resource limits
2307            from the old SID.  If not, reset all soft limits to
2308            the lower of the current task's hard limit and the init
2309            task's soft limit.  Note that the setting of hard limits
2310            (even to lower them) can be controlled by the setrlimit
2311            check. The inclusion of the init task's soft limit into
2312            the computation is to avoid resetting soft limits higher
2313            than the default soft limit for cases where the default
2314            is lower than the hard limit, e.g. RLIMIT_CORE or
2315            RLIMIT_STACK.*/
2316         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2317                           PROCESS__RLIMITINH, NULL);
2318         if (rc) {
2319                 for (i = 0; i < RLIM_NLIMITS; i++) {
2320                         rlim = current->signal->rlim + i;
2321                         initrlim = init_task.signal->rlim+i;
2322                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2323                 }
2324                 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
2325                         /*
2326                          * This will cause RLIMIT_CPU calculations
2327                          * to be refigured.
2328                          */
2329                         current->it_prof_expires = jiffies_to_cputime(1);
2330                 }
2331         }
2332
2333         /* Wake up the parent if it is waiting so that it can
2334            recheck wait permission to the new task SID. */
2335         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2336 }
2337
2338 /* superblock security operations */
2339
2340 static int selinux_sb_alloc_security(struct super_block *sb)
2341 {
2342         return superblock_alloc_security(sb);
2343 }
2344
2345 static void selinux_sb_free_security(struct super_block *sb)
2346 {
2347         superblock_free_security(sb);
2348 }
2349
2350 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2351 {
2352         if (plen > olen)
2353                 return 0;
2354
2355         return !memcmp(prefix, option, plen);
2356 }
2357
2358 static inline int selinux_option(char *option, int len)
2359 {
2360         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2361                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2362                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2363                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len));
2364 }
2365
2366 static inline void take_option(char **to, char *from, int *first, int len)
2367 {
2368         if (!*first) {
2369                 **to = ',';
2370                 *to += 1;
2371         } else
2372                 *first = 0;
2373         memcpy(*to, from, len);
2374         *to += len;
2375 }
2376
2377 static inline void take_selinux_option(char **to, char *from, int *first,
2378                                        int len)
2379 {
2380         int current_size = 0;
2381
2382         if (!*first) {
2383                 **to = '|';
2384                 *to += 1;
2385         } else
2386                 *first = 0;
2387
2388         while (current_size < len) {
2389                 if (*from != '"') {
2390                         **to = *from;
2391                         *to += 1;
2392                 }
2393                 from += 1;
2394                 current_size += 1;
2395         }
2396 }
2397
2398 static int selinux_sb_copy_data(char *orig, char *copy)
2399 {
2400         int fnosec, fsec, rc = 0;
2401         char *in_save, *in_curr, *in_end;
2402         char *sec_curr, *nosec_save, *nosec;
2403         int open_quote = 0;
2404
2405         in_curr = orig;
2406         sec_curr = copy;
2407
2408         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2409         if (!nosec) {
2410                 rc = -ENOMEM;
2411                 goto out;
2412         }
2413
2414         nosec_save = nosec;
2415         fnosec = fsec = 1;
2416         in_save = in_end = orig;
2417
2418         do {
2419                 if (*in_end == '"')
2420                         open_quote = !open_quote;
2421                 if ((*in_end == ',' && open_quote == 0) ||
2422                                 *in_end == '\0') {
2423                         int len = in_end - in_curr;
2424
2425                         if (selinux_option(in_curr, len))
2426                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2427                         else
2428                                 take_option(&nosec, in_curr, &fnosec, len);
2429
2430                         in_curr = in_end + 1;
2431                 }
2432         } while (*in_end++);
2433
2434         strcpy(in_save, nosec_save);
2435         free_page((unsigned long)nosec_save);
2436 out:
2437         return rc;
2438 }
2439
2440 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2441 {
2442         struct avc_audit_data ad;
2443         int rc;
2444
2445         rc = superblock_doinit(sb, data);
2446         if (rc)
2447                 return rc;
2448
2449         AVC_AUDIT_DATA_INIT(&ad, FS);
2450         ad.u.fs.path.dentry = sb->s_root;
2451         return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2452 }
2453
2454 static int selinux_sb_statfs(struct dentry *dentry)
2455 {
2456         struct avc_audit_data ad;
2457
2458         AVC_AUDIT_DATA_INIT(&ad, FS);
2459         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2460         return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2461 }
2462
2463 static int selinux_mount(char *dev_name,
2464                          struct path *path,
2465                          char *type,
2466                          unsigned long flags,
2467                          void *data)
2468 {
2469         int rc;
2470
2471         rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
2472         if (rc)
2473                 return rc;
2474
2475         if (flags & MS_REMOUNT)
2476                 return superblock_has_perm(current, path->mnt->mnt_sb,
2477                                            FILESYSTEM__REMOUNT, NULL);
2478         else
2479                 return dentry_has_perm(current, path->mnt, path->dentry,
2480                                        FILE__MOUNTON);
2481 }
2482
2483 static int selinux_umount(struct vfsmount *mnt, int flags)
2484 {
2485         int rc;
2486
2487         rc = secondary_ops->sb_umount(mnt, flags);
2488         if (rc)
2489                 return rc;
2490
2491         return superblock_has_perm(current, mnt->mnt_sb,
2492                                    FILESYSTEM__UNMOUNT, NULL);
2493 }
2494
2495 /* inode security operations */
2496
2497 static int selinux_inode_alloc_security(struct inode *inode)
2498 {
2499         return inode_alloc_security(inode);
2500 }
2501
2502 static void selinux_inode_free_security(struct inode *inode)
2503 {
2504         inode_free_security(inode);
2505 }
2506
2507 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2508                                        char **name, void **value,
2509                                        size_t *len)
2510 {
2511         struct task_security_struct *tsec;
2512         struct inode_security_struct *dsec;
2513         struct superblock_security_struct *sbsec;
2514         u32 newsid, clen;
2515         int rc;
2516         char *namep = NULL, *context;
2517
2518         tsec = current->security;
2519         dsec = dir->i_security;
2520         sbsec = dir->i_sb->s_security;
2521
2522         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2523                 newsid = tsec->create_sid;
2524         } else {
2525                 rc = security_transition_sid(tsec->sid, dsec->sid,
2526                                              inode_mode_to_security_class(inode->i_mode),
2527                                              &newsid);
2528                 if (rc) {
2529                         printk(KERN_WARNING "%s:  "
2530                                "security_transition_sid failed, rc=%d (dev=%s "
2531                                "ino=%ld)\n",
2532                                __func__,
2533                                -rc, inode->i_sb->s_id, inode->i_ino);
2534                         return rc;
2535                 }
2536         }
2537
2538         /* Possibly defer initialization to selinux_complete_init. */
2539         if (sbsec->initialized) {
2540                 struct inode_security_struct *isec = inode->i_security;
2541                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2542                 isec->sid = newsid;
2543                 isec->initialized = 1;
2544         }
2545
2546         if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2547                 return -EOPNOTSUPP;
2548
2549         if (name) {
2550                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2551                 if (!namep)
2552                         return -ENOMEM;
2553                 *name = namep;
2554         }
2555
2556         if (value && len) {
2557                 rc = security_sid_to_context_force(newsid, &context, &clen);
2558                 if (rc) {
2559                         kfree(namep);
2560                         return rc;
2561                 }
2562                 *value = context;
2563                 *len = clen;
2564         }
2565
2566         return 0;
2567 }
2568
2569 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2570 {
2571         return may_create(dir, dentry, SECCLASS_FILE);
2572 }
2573
2574 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2575 {
2576         int rc;
2577
2578         rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
2579         if (rc)
2580                 return rc;
2581         return may_link(dir, old_dentry, MAY_LINK);
2582 }
2583
2584 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2585 {
2586         int rc;
2587
2588         rc = secondary_ops->inode_unlink(dir, dentry);
2589         if (rc)
2590                 return rc;
2591         return may_link(dir, dentry, MAY_UNLINK);
2592 }
2593
2594 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2595 {
2596         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2597 }
2598
2599 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2600 {
2601         return may_create(dir, dentry, SECCLASS_DIR);
2602 }
2603
2604 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2605 {
2606         return may_link(dir, dentry, MAY_RMDIR);
2607 }
2608
2609 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2610 {
2611         int rc;
2612
2613         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2614         if (rc)
2615                 return rc;
2616
2617         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2618 }
2619
2620 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2621                                 struct inode *new_inode, struct dentry *new_dentry)
2622 {
2623         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2624 }
2625
2626 static int selinux_inode_readlink(struct dentry *dentry)
2627 {
2628         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2629 }
2630
2631 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2632 {
2633         int rc;
2634
2635         rc = secondary_ops->inode_follow_link(dentry, nameidata);
2636         if (rc)
2637                 return rc;
2638         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2639 }
2640
2641 static int selinux_inode_permission(struct inode *inode, int mask)
2642 {
2643         int rc;
2644
2645         rc = secondary_ops->inode_permission(inode, mask);
2646         if (rc)
2647                 return rc;
2648
2649         if (!mask) {
2650                 /* No permission to check.  Existence test. */
2651                 return 0;
2652         }
2653
2654         return inode_has_perm(current, inode,
2655                                open_file_mask_to_av(inode->i_mode, mask), NULL);
2656 }
2657
2658 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2659 {
2660         int rc;
2661
2662         rc = secondary_ops->inode_setattr(dentry, iattr);
2663         if (rc)
2664                 return rc;
2665
2666         if (iattr->ia_valid & ATTR_FORCE)
2667                 return 0;
2668
2669         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2670                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2671                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2672
2673         return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2674 }
2675
2676 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2677 {
2678         return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2679 }
2680
2681 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2682 {
2683         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2684                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2685                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2686                         if (!capable(CAP_SETFCAP))
2687                                 return -EPERM;
2688                 } else if (!capable(CAP_SYS_ADMIN)) {
2689                         /* A different attribute in the security namespace.
2690                            Restrict to administrator. */
2691                         return -EPERM;
2692                 }
2693         }
2694
2695         /* Not an attribute we recognize, so just check the
2696            ordinary setattr permission. */
2697         return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2698 }
2699
2700 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2701                                   const void *value, size_t size, int flags)
2702 {
2703         struct task_security_struct *tsec = current->security;
2704         struct inode *inode = dentry->d_inode;
2705         struct inode_security_struct *isec = inode->i_security;
2706         struct superblock_security_struct *sbsec;
2707         struct avc_audit_data ad;
2708         u32 newsid;
2709         int rc = 0;
2710
2711         if (strcmp(name, XATTR_NAME_SELINUX))
2712                 return selinux_inode_setotherxattr(dentry, name);
2713
2714         sbsec = inode->i_sb->s_security;
2715         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2716                 return -EOPNOTSUPP;
2717
2718         if (!is_owner_or_cap(inode))
2719                 return -EPERM;
2720
2721         AVC_AUDIT_DATA_INIT(&ad, FS);
2722         ad.u.fs.path.dentry = dentry;
2723
2724         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2725                           FILE__RELABELFROM, &ad);
2726         if (rc)
2727                 return rc;
2728
2729         rc = security_context_to_sid(value, size, &newsid);
2730         if (rc == -EINVAL) {
2731                 if (!capable(CAP_MAC_ADMIN))
2732                         return rc;
2733                 rc = security_context_to_sid_force(value, size, &newsid);
2734         }
2735         if (rc)
2736                 return rc;
2737
2738         rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2739                           FILE__RELABELTO, &ad);
2740         if (rc)
2741                 return rc;
2742
2743         rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2744                                           isec->sclass);
2745         if (rc)
2746                 return rc;
2747
2748         return avc_has_perm(newsid,
2749                             sbsec->sid,
2750                             SECCLASS_FILESYSTEM,
2751                             FILESYSTEM__ASSOCIATE,
2752                             &ad);
2753 }
2754
2755 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2756                                         const void *value, size_t size,
2757                                         int flags)
2758 {
2759         struct inode *inode = dentry->d_inode;
2760         struct inode_security_struct *isec = inode->i_security;
2761         u32 newsid;
2762         int rc;
2763
2764         if (strcmp(name, XATTR_NAME_SELINUX)) {
2765                 /* Not an attribute we recognize, so nothing to do. */
2766                 return;
2767         }
2768
2769         rc = security_context_to_sid_force(value, size, &newsid);
2770         if (rc) {
2771                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2772                        "for (%s, %lu), rc=%d\n",
2773                        inode->i_sb->s_id, inode->i_ino, -rc);
2774                 return;
2775         }
2776
2777         isec->sid = newsid;
2778         return;
2779 }
2780
2781 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2782 {
2783         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2784 }
2785
2786 static int selinux_inode_listxattr(struct dentry *dentry)
2787 {
2788         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2789 }
2790
2791 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2792 {
2793         if (strcmp(name, XATTR_NAME_SELINUX))
2794                 return selinux_inode_setotherxattr(dentry, name);
2795
2796         /* No one is allowed to remove a SELinux security label.
2797            You can change the label, but all data must be labeled. */
2798         return -EACCES;
2799 }
2800
2801 /*
2802  * Copy the inode security context value to the user.
2803  *
2804  * Permission check is handled by selinux_inode_getxattr hook.
2805  */
2806 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2807 {
2808         u32 size;
2809         int error;
2810         char *context = NULL;
2811         struct task_security_struct *tsec = current->security;
2812         struct inode_security_struct *isec = inode->i_security;
2813
2814         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2815                 return -EOPNOTSUPP;
2816
2817         /*
2818          * If the caller has CAP_MAC_ADMIN, then get the raw context
2819          * value even if it is not defined by current policy; otherwise,
2820          * use the in-core value under current policy.
2821          * Use the non-auditing forms of the permission checks since
2822          * getxattr may be called by unprivileged processes commonly
2823          * and lack of permission just means that we fall back to the
2824          * in-core context value, not a denial.
2825          */
2826         error = secondary_ops->capable(current, CAP_MAC_ADMIN);
2827         if (!error)
2828                 error = avc_has_perm_noaudit(tsec->sid, tsec->sid,
2829                                              SECCLASS_CAPABILITY2,
2830                                              CAPABILITY2__MAC_ADMIN,
2831                                              0,
2832                                              NULL);
2833         if (!error)
2834                 error = security_sid_to_context_force(isec->sid, &context,
2835                                                       &size);
2836         else
2837                 error = security_sid_to_context(isec->sid, &context, &size);
2838         if (error)
2839                 return error;
2840         error = size;
2841         if (alloc) {
2842                 *buffer = context;
2843                 goto out_nofree;
2844         }
2845         kfree(context);
2846 out_nofree:
2847         return error;
2848 }
2849
2850 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2851                                      const void *value, size_t size, int flags)
2852 {
2853         struct inode_security_struct *isec = inode->i_security;
2854         u32 newsid;
2855         int rc;
2856
2857         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2858                 return -EOPNOTSUPP;
2859
2860         if (!value || !size)
2861                 return -EACCES;
2862
2863         rc = security_context_to_sid((void *)value, size, &newsid);
2864         if (rc)
2865                 return rc;
2866
2867         isec->sid = newsid;
2868         return 0;
2869 }
2870
2871 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2872 {
2873         const int len = sizeof(XATTR_NAME_SELINUX);
2874         if (buffer && len <= buffer_size)
2875                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2876         return len;
2877 }
2878
2879 static int selinux_inode_need_killpriv(struct dentry *dentry)
2880 {
2881         return secondary_ops->inode_need_killpriv(dentry);
2882 }
2883
2884 static int selinux_inode_killpriv(struct dentry *dentry)
2885 {
2886         return secondary_ops->inode_killpriv(dentry);
2887 }
2888
2889 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2890 {
2891         struct inode_security_struct *isec = inode->i_security;
2892         *secid = isec->sid;
2893 }
2894
2895 /* file security operations */
2896
2897 static int selinux_revalidate_file_permission(struct file *file, int mask)
2898 {
2899         int rc;
2900         struct inode *inode = file->f_path.dentry->d_inode;
2901
2902         if (!mask) {
2903                 /* No permission to check.  Existence test. */
2904                 return 0;
2905         }
2906
2907         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2908         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2909                 mask |= MAY_APPEND;
2910
2911         rc = file_has_perm(current, file,
2912                            file_mask_to_av(inode->i_mode, mask));
2913         if (rc)
2914                 return rc;
2915
2916         return selinux_netlbl_inode_permission(inode, mask);
2917 }
2918
2919 static int selinux_file_permission(struct file *file, int mask)
2920 {
2921         struct inode *inode = file->f_path.dentry->d_inode;
2922         struct task_security_struct *tsec = current->security;
2923         struct file_security_struct *fsec = file->f_security;
2924         struct inode_security_struct *isec = inode->i_security;
2925
2926         if (!mask) {
2927                 /* No permission to check.  Existence test. */
2928                 return 0;
2929         }
2930
2931         if (tsec->sid == fsec->sid && fsec->isid == isec->sid
2932             && fsec->pseqno == avc_policy_seqno())
2933                 return selinux_netlbl_inode_permission(inode, mask);
2934
2935         return selinux_revalidate_file_permission(file, mask);
2936 }
2937
2938 static int selinux_file_alloc_security(struct file *file)
2939 {
2940         return file_alloc_security(file);
2941 }
2942
2943 static void selinux_file_free_security(struct file *file)
2944 {
2945         file_free_security(file);
2946 }
2947
2948 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2949                               unsigned long arg)
2950 {
2951         u32 av = 0;
2952
2953         if (_IOC_DIR(cmd) & _IOC_WRITE)
2954                 av |= FILE__WRITE;
2955         if (_IOC_DIR(cmd) & _IOC_READ)
2956                 av |= FILE__READ;
2957         if (!av)
2958                 av = FILE__IOCTL;
2959
2960         return file_has_perm(current, file, av);
2961 }
2962
2963 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2964 {
2965 #ifndef CONFIG_PPC32
2966         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2967                 /*
2968                  * We are making executable an anonymous mapping or a
2969                  * private file mapping that will also be writable.
2970                  * This has an additional check.
2971                  */
2972                 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2973                 if (rc)
2974                         return rc;
2975         }
2976 #endif
2977
2978         if (file) {
2979                 /* read access is always possible with a mapping */
2980                 u32 av = FILE__READ;
2981
2982                 /* write access only matters if the mapping is shared */
2983                 if (shared && (prot & PROT_WRITE))
2984                         av |= FILE__WRITE;
2985
2986                 if (prot & PROT_EXEC)
2987                         av |= FILE__EXECUTE;
2988
2989                 return file_has_perm(current, file, av);
2990         }
2991         return 0;
2992 }
2993
2994 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2995                              unsigned long prot, unsigned long flags,
2996                              unsigned long addr, unsigned long addr_only)
2997 {
2998         int rc = 0;
2999         u32 sid = ((struct task_security_struct *)(current->security))->sid;
3000
3001         if (addr < mmap_min_addr)
3002                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3003                                   MEMPROTECT__MMAP_ZERO, NULL);
3004         if (rc || addr_only)
3005                 return rc;
3006
3007         if (selinux_checkreqprot)
3008                 prot = reqprot;
3009
3010         return file_map_prot_check(file, prot,
3011                                    (flags & MAP_TYPE) == MAP_SHARED);
3012 }
3013
3014 static int selinux_file_mprotect(struct vm_area_struct *vma,
3015                                  unsigned long reqprot,
3016                                  unsigned long prot)
3017 {
3018         int rc;
3019
3020         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
3021         if (rc)
3022                 return rc;
3023
3024         if (selinux_checkreqprot)
3025                 prot = reqprot;
3026
3027 #ifndef CONFIG_PPC32
3028         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3029                 rc = 0;
3030                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3031                     vma->vm_end <= vma->vm_mm->brk) {
3032                         rc = task_has_perm(current, current,
3033                                            PROCESS__EXECHEAP);
3034                 } else if (!vma->vm_file &&
3035                            vma->vm_start <= vma->vm_mm->start_stack &&
3036                            vma->vm_end >= vma->vm_mm->start_stack) {
3037                         rc = task_has_perm(current, current, PROCESS__EXECSTACK);
3038                 } else if (vma->vm_file && vma->anon_vma) {
3039                         /*
3040                          * We are making executable a file mapping that has
3041                          * had some COW done. Since pages might have been
3042                          * written, check ability to execute the possibly
3043                          * modified content.  This typically should only
3044                          * occur for text relocations.
3045                          */
3046                         rc = file_has_perm(current, vma->vm_file,
3047                                            FILE__EXECMOD);
3048                 }
3049                 if (rc)
3050                         return rc;
3051         }
3052 #endif
3053
3054         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3055 }
3056
3057 static int selinux_file_lock(struct file *file, unsigned int cmd)
3058 {
3059         return file_has_perm(current, file, FILE__LOCK);
3060 }
3061
3062 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3063                               unsigned long arg)
3064 {
3065         int err = 0;
3066
3067         switch (cmd) {
3068         case F_SETFL:
3069                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3070                         err = -EINVAL;
3071                         break;
3072                 }
3073
3074                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3075                         err = file_has_perm(current, file, FILE__WRITE);
3076                         break;
3077                 }
3078                 /* fall through */
3079         case F_SETOWN:
3080         case F_SETSIG:
3081         case F_GETFL:
3082         case F_GETOWN:
3083         case F_GETSIG:
3084                 /* Just check FD__USE permission */
3085                 err = file_has_perm(current, file, 0);
3086                 break;
3087         case F_GETLK:
3088         case F_SETLK:
3089         case F_SETLKW:
3090 #if BITS_PER_LONG == 32
3091         case F_GETLK64:
3092         case F_SETLK64:
3093         case F_SETLKW64:
3094 #endif
3095                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3096                         err = -EINVAL;
3097                         break;
3098                 }
3099                 err = file_has_perm(current, file, FILE__LOCK);
3100                 break;
3101         }
3102
3103         return err;
3104 }
3105
3106 static int selinux_file_set_fowner(struct file *file)
3107 {
3108         struct task_security_struct *tsec;
3109         struct file_security_struct *fsec;
3110
3111         tsec = current->security;
3112         fsec = file->f_security;
3113         fsec->fown_sid = tsec->sid;
3114
3115         return 0;
3116 }
3117
3118 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3119                                        struct fown_struct *fown, int signum)
3120 {
3121         struct file *file;
3122         u32 perm;
3123         struct task_security_struct *tsec;
3124         struct file_security_struct *fsec;
3125
3126         /* struct fown_struct is never outside the context of a struct file */
3127         file = container_of(fown, struct file, f_owner);
3128
3129         tsec = tsk->security;
3130         fsec = file->f_security;
3131
3132         if (!signum)
3133                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3134         else
3135                 perm = signal_to_av(signum);
3136
3137         return avc_has_perm(fsec->fown_sid, tsec->sid,
3138                             SECCLASS_PROCESS, perm, NULL);
3139 }
3140
3141 static int selinux_file_receive(struct file *file)
3142 {
3143         return file_has_perm(current, file, file_to_av(file));
3144 }
3145
3146 static int selinux_dentry_open(struct file *file)
3147 {
3148         struct file_security_struct *fsec;
3149         struct inode *inode;
3150         struct inode_security_struct *isec;
3151         inode = file->f_path.dentry->d_inode;
3152         fsec = file->f_security;
3153         isec = inode->i_security;
3154         /*
3155          * Save inode label and policy sequence number
3156          * at open-time so that selinux_file_permission
3157          * can determine whether revalidation is necessary.
3158          * Task label is already saved in the file security
3159          * struct as its SID.
3160          */
3161         fsec->isid = isec->sid;
3162         fsec->pseqno = avc_policy_seqno();
3163         /*
3164          * Since the inode label or policy seqno may have changed
3165          * between the selinux_inode_permission check and the saving
3166          * of state above, recheck that access is still permitted.
3167          * Otherwise, access might never be revalidated against the
3168          * new inode label or new policy.
3169          * This check is not redundant - do not remove.
3170          */
3171         return inode_has_perm(current, inode, file_to_av(file), NULL);
3172 }
3173
3174 /* task security operations */
3175
3176 static int selinux_task_create(unsigned long clone_flags)
3177 {
3178         int rc;
3179
3180         rc = secondary_ops->task_create(clone_flags);
3181         if (rc)
3182                 return rc;
3183
3184         return task_has_perm(current, current, PROCESS__FORK);
3185 }
3186
3187 static int selinux_task_alloc_security(struct task_struct *tsk)
3188 {
3189         struct task_security_struct *tsec1, *tsec2;
3190         int rc;
3191
3192         tsec1 = current->security;
3193
3194         rc = task_alloc_security(tsk);
3195         if (rc)
3196                 return rc;
3197         tsec2 = tsk->security;
3198
3199         tsec2->osid = tsec1->osid;
3200         tsec2->sid = tsec1->sid;
3201
3202         /* Retain the exec, fs, key, and sock SIDs across fork */
3203         tsec2->exec_sid = tsec1->exec_sid;
3204         tsec2->create_sid = tsec1->create_sid;
3205         tsec2->keycreate_sid = tsec1->keycreate_sid;
3206         tsec2->sockcreate_sid = tsec1->sockcreate_sid;
3207
3208         return 0;
3209 }
3210
3211 static void selinux_task_free_security(struct task_struct *tsk)
3212 {
3213         task_free_security(tsk);
3214 }
3215
3216 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3217 {
3218         /* Since setuid only affects the current process, and
3219            since the SELinux controls are not based on the Linux
3220            identity attributes, SELinux does not need to control
3221            this operation.  However, SELinux does control the use
3222            of the CAP_SETUID and CAP_SETGID capabilities using the
3223            capable hook. */
3224         return 0;
3225 }
3226
3227 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3228 {
3229         return secondary_ops->task_post_setuid(id0, id1, id2, flags);
3230 }
3231
3232 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3233 {
3234         /* See the comment for setuid above. */
3235         return 0;
3236 }
3237
3238 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3239 {
3240         return task_has_perm(current, p, PROCESS__SETPGID);
3241 }
3242
3243 static int selinux_task_getpgid(struct task_struct *p)
3244 {
3245         return task_has_perm(current, p, PROCESS__GETPGID);
3246 }
3247
3248 static int selinux_task_getsid(struct task_struct *p)
3249 {
3250         return task_has_perm(current, p, PROCESS__GETSESSION);
3251 }
3252
3253 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3254 {
3255         struct task_security_struct *tsec = p->security;
3256         *secid = tsec->sid;
3257 }
3258
3259 static int selinux_task_setgroups(struct group_info *group_info)
3260 {
3261         /* See the comment for setuid above. */
3262         return 0;
3263 }
3264
3265 static int selinux_task_setnice(struct task_struct *p, int nice)
3266 {
3267         int rc;
3268
3269         rc = secondary_ops->task_setnice(p, nice);
3270         if (rc)
3271                 return rc;
3272
3273         return task_has_perm(current, p, PROCESS__SETSCHED);
3274 }
3275
3276 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3277 {
3278         int rc;
3279
3280         rc = secondary_ops->task_setioprio(p, ioprio);
3281         if (rc)
3282                 return rc;
3283
3284         return task_has_perm(current, p, PROCESS__SETSCHED);
3285 }
3286
3287 static int selinux_task_getioprio(struct task_struct *p)
3288 {
3289         return task_has_perm(current, p, PROCESS__GETSCHED);
3290 }
3291
3292 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3293 {
3294         struct rlimit *old_rlim = current->signal->rlim + resource;
3295         int rc;
3296
3297         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3298         if (rc)
3299                 return rc;
3300
3301         /* Control the ability to change the hard limit (whether
3302            lowering or raising it), so that the hard limit can
3303            later be used as a safe reset point for the soft limit
3304            upon context transitions. See selinux_bprm_apply_creds. */
3305         if (old_rlim->rlim_max != new_rlim->rlim_max)
3306                 return task_has_perm(current, current, PROCESS__SETRLIMIT);
3307
3308         return 0;
3309 }
3310
3311 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3312 {
3313         int rc;
3314
3315         rc = secondary_ops->task_setscheduler(p, policy, lp);
3316         if (rc)
3317                 return rc;
3318
3319         return task_has_perm(current, p, PROCESS__SETSCHED);
3320 }
3321
3322 static int selinux_task_getscheduler(struct task_struct *p)
3323 {
3324         return task_has_perm(current, p, PROCESS__GETSCHED);
3325 }
3326
3327 static int selinux_task_movememory(struct task_struct *p)
3328 {
3329         return task_has_perm(current, p, PROCESS__SETSCHED);
3330 }
3331
3332 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3333                                 int sig, u32 secid)
3334 {
3335         u32 perm;
3336         int rc;
3337         struct task_security_struct *tsec;
3338
3339         rc = secondary_ops->task_kill(p, info, sig, secid);
3340         if (rc)
3341                 return rc;
3342
3343         if (!sig)
3344                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3345         else
3346                 perm = signal_to_av(sig);
3347         tsec = p->security;
3348         if (secid)
3349                 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
3350         else
3351                 rc = task_has_perm(current, p, perm);
3352         return rc;
3353 }
3354
3355 static int selinux_task_prctl(int option,
3356                               unsigned long arg2,
3357                               unsigned long arg3,
3358                               unsigned long arg4,
3359                               unsigned long arg5,
3360                               long *rc_p)
3361 {
3362         /* The current prctl operations do not appear to require
3363            any SELinux controls since they merely observe or modify
3364            the state of the current process. */
3365         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p);
3366 }
3367
3368 static int selinux_task_wait(struct task_struct *p)
3369 {
3370         return task_has_perm(p, current, PROCESS__SIGCHLD);
3371 }
3372
3373 static void selinux_task_reparent_to_init(struct task_struct *p)
3374 {
3375         struct task_security_struct *tsec;
3376
3377         secondary_ops->task_reparent_to_init(p);
3378
3379         tsec = p->security;
3380         tsec->osid = tsec->sid;
3381         tsec->sid = SECINITSID_KERNEL;
3382         return;
3383 }
3384
3385 static void selinux_task_to_inode(struct task_struct *p,
3386                                   struct inode *inode)
3387 {
3388         struct task_security_struct *tsec = p->security;
3389         struct inode_security_struct *isec = inode->i_security;
3390
3391         isec->sid = tsec->sid;
3392         isec->initialized = 1;
3393         return;
3394 }
3395
3396 /* Returns error only if unable to parse addresses */
3397 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3398                         struct avc_audit_data *ad, u8 *proto)
3399 {
3400         int offset, ihlen, ret = -EINVAL;
3401         struct iphdr _iph, *ih;
3402
3403         offset = skb_network_offset(skb);
3404         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3405         if (ih == NULL)
3406                 goto out;
3407
3408         ihlen = ih->ihl * 4;
3409         if (ihlen < sizeof(_iph))
3410                 goto out;
3411
3412         ad->u.net.v4info.saddr = ih->saddr;
3413         ad->u.net.v4info.daddr = ih->daddr;
3414         ret = 0;
3415
3416         if (proto)
3417                 *proto = ih->protocol;
3418
3419         switch (ih->protocol) {
3420         case IPPROTO_TCP: {
3421                 struct tcphdr _tcph, *th;
3422
3423                 if (ntohs(ih->frag_off) & IP_OFFSET)
3424                         break;
3425
3426                 offset += ihlen;
3427                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3428                 if (th == NULL)
3429                         break;
3430
3431                 ad->u.net.sport = th->source;
3432                 ad->u.net.dport = th->dest;
3433                 break;
3434         }
3435
3436         case IPPROTO_UDP: {
3437                 struct udphdr _udph, *uh;
3438
3439                 if (ntohs(ih->frag_off) & IP_OFFSET)
3440                         break;
3441
3442                 offset += ihlen;
3443                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3444                 if (uh == NULL)
3445                         break;
3446
3447                 ad->u.net.sport = uh->source;
3448                 ad->u.net.dport = uh->dest;
3449                 break;
3450         }
3451
3452         case IPPROTO_DCCP: {
3453                 struct dccp_hdr _dccph, *dh;
3454
3455                 if (ntohs(ih->frag_off) & IP_OFFSET)
3456                         break;
3457
3458                 offset += ihlen;
3459                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3460                 if (dh == NULL)
3461                         break;
3462
3463                 ad->u.net.sport = dh->dccph_sport;
3464                 ad->u.net.dport = dh->dccph_dport;
3465                 break;
3466         }
3467
3468         default:
3469                 break;
3470         }
3471 out:
3472         return ret;
3473 }
3474
3475 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3476
3477 /* Returns error only if unable to parse addresses */
3478 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3479                         struct avc_audit_data *ad, u8 *proto)
3480 {
3481         u8 nexthdr;
3482         int ret = -EINVAL, offset;
3483         struct ipv6hdr _ipv6h, *ip6;
3484
3485         offset = skb_network_offset(skb);
3486         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3487         if (ip6 == NULL)
3488                 goto out;
3489
3490         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3491         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3492         ret = 0;
3493
3494         nexthdr = ip6->nexthdr;
3495         offset += sizeof(_ipv6h);
3496         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3497         if (offset < 0)
3498                 goto out;
3499
3500         if (proto)
3501                 *proto = nexthdr;
3502
3503         switch (nexthdr) {
3504         case IPPROTO_TCP: {
3505                 struct tcphdr _tcph, *th;
3506
3507                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3508                 if (th == NULL)
3509                         break;
3510
3511                 ad->u.net.sport = th->source;
3512                 ad->u.net.dport = th->dest;
3513                 break;
3514         }
3515
3516         case IPPROTO_UDP: {
3517                 struct udphdr _udph, *uh;
3518
3519                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3520                 if (uh == NULL)
3521                         break;
3522
3523                 ad->u.net.sport = uh->source;
3524                 ad->u.net.dport = uh->dest;
3525                 break;
3526         }
3527
3528         case IPPROTO_DCCP: {
3529                 struct dccp_hdr _dccph, *dh;
3530
3531                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3532                 if (dh == NULL)
3533                         break;
3534
3535                 ad->u.net.sport = dh->dccph_sport;
3536                 ad->u.net.dport = dh->dccph_dport;
3537                 break;
3538         }
3539
3540         /* includes fragments */
3541         default:
3542                 break;
3543         }
3544 out:
3545         return ret;
3546 }
3547
3548 #endif /* IPV6 */
3549
3550 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3551                              char **_addrp, int src, u8 *proto)
3552 {
3553         char *addrp;
3554         int ret;
3555
3556         switch (ad->u.net.family) {
3557         case PF_INET:
3558                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3559                 if (ret)
3560                         goto parse_error;
3561                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3562                                        &ad->u.net.v4info.daddr);
3563                 goto okay;
3564
3565 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3566         case PF_INET6:
3567                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3568                 if (ret)
3569                         goto parse_error;
3570                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3571                                        &ad->u.net.v6info.daddr);
3572                 goto okay;
3573 #endif  /* IPV6 */
3574         default:
3575                 addrp = NULL;
3576                 goto okay;
3577         }
3578
3579 parse_error:
3580         printk(KERN_WARNING
3581                "SELinux: failure in selinux_parse_skb(),"
3582                " unable to parse packet\n");
3583         return ret;
3584
3585 okay:
3586         if (_addrp)
3587                 *_addrp = addrp;
3588         return 0;
3589 }
3590
3591 /**
3592  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3593  * @skb: the packet
3594  * @family: protocol family
3595  * @sid: the packet's peer label SID
3596  *
3597  * Description:
3598  * Check the various different forms of network peer labeling and determine
3599  * the peer label/SID for the packet; most of the magic actually occurs in
3600  * the security server function security_net_peersid_cmp().  The function
3601  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3602  * or -EACCES if @sid is invalid due to inconsistencies with the different
3603  * peer labels.
3604  *
3605  */
3606 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3607 {
3608         int err;
3609         u32 xfrm_sid;
3610         u32 nlbl_sid;
3611         u32 nlbl_type;
3612
3613         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3614         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3615
3616         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3617         if (unlikely(err)) {
3618                 printk(KERN_WARNING
3619                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3620                        " unable to determine packet's peer label\n");
3621                 return -EACCES;
3622         }
3623
3624         return 0;
3625 }
3626
3627 /* socket security operations */
3628 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3629                            u32 perms)
3630 {
3631         struct inode_security_struct *isec;
3632         struct task_security_struct *tsec;
3633         struct avc_audit_data ad;
3634         int err = 0;
3635
3636         tsec = task->security;
3637         isec = SOCK_INODE(sock)->i_security;
3638
3639         if (isec->sid == SECINITSID_KERNEL)
3640                 goto out;
3641
3642         AVC_AUDIT_DATA_INIT(&ad, NET);
3643         ad.u.net.sk = sock->sk;
3644         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3645
3646 out:
3647         return err;
3648 }
3649
3650 static int selinux_socket_create(int family, int type,
3651                                  int protocol, int kern)
3652 {
3653         int err = 0;
3654         struct task_security_struct *tsec;
3655         u32 newsid;
3656
3657         if (kern)
3658                 goto out;
3659
3660         tsec = current->security;
3661         newsid = tsec->sockcreate_sid ? : tsec->sid;
3662         err = avc_has_perm(tsec->sid, newsid,
3663                            socket_type_to_security_class(family, type,
3664                            protocol), SOCKET__CREATE, NULL);
3665
3666 out:
3667         return err;
3668 }
3669
3670 static int selinux_socket_post_create(struct socket *sock, int family,
3671                                       int type, int protocol, int kern)
3672 {
3673         int err = 0;
3674         struct inode_security_struct *isec;
3675         struct task_security_struct *tsec;
3676         struct sk_security_struct *sksec;
3677         u32 newsid;
3678
3679         isec = SOCK_INODE(sock)->i_security;
3680
3681         tsec = current->security;
3682         newsid = tsec->sockcreate_sid ? : tsec->sid;
3683         isec->sclass = socket_type_to_security_class(family, type, protocol);
3684         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3685         isec->initialized = 1;
3686
3687         if (sock->sk) {
3688                 sksec = sock->sk->sk_security;
3689                 sksec->sid = isec->sid;
3690                 sksec->sclass = isec->sclass;
3691                 err = selinux_netlbl_socket_post_create(sock);
3692         }
3693
3694         return err;
3695 }
3696
3697 /* Range of port numbers used to automatically bind.
3698    Need to determine whether we should perform a name_bind
3699    permission check between the socket and the port number. */
3700
3701 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3702 {
3703         u16 family;
3704         int err;
3705
3706         err = socket_has_perm(current, sock, SOCKET__BIND);
3707         if (err)
3708                 goto out;
3709
3710         /*
3711          * If PF_INET or PF_INET6, check name_bind permission for the port.
3712          * Multiple address binding for SCTP is not supported yet: we just
3713          * check the first address now.
3714          */
3715         family = sock->sk->sk_family;
3716         if (family == PF_INET || family == PF_INET6) {
3717                 char *addrp;
3718                 struct inode_security_struct *isec;
3719                 struct task_security_struct *tsec;
3720                 struct avc_audit_data ad;
3721                 struct sockaddr_in *addr4 = NULL;
3722                 struct sockaddr_in6 *addr6 = NULL;
3723                 unsigned short snum;
3724                 struct sock *sk = sock->sk;
3725                 u32 sid, node_perm;
3726
3727                 tsec = current->security;
3728                 isec = SOCK_INODE(sock)->i_security;
3729
3730                 if (family == PF_INET) {
3731                         addr4 = (struct sockaddr_in *)address;
3732                         snum = ntohs(addr4->sin_port);
3733                         addrp = (char *)&addr4->sin_addr.s_addr;
3734                 } else {
3735                         addr6 = (struct sockaddr_in6 *)address;
3736                         snum = ntohs(addr6->sin6_port);
3737                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3738                 }
3739
3740                 if (snum) {
3741                         int low, high;
3742
3743                         inet_get_local_port_range(&low, &high);
3744
3745                         if (snum < max(PROT_SOCK, low) || snum > high) {
3746                                 err = sel_netport_sid(sk->sk_protocol,
3747                                                       snum, &sid);
3748                                 if (err)
3749                                         goto out;
3750                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3751                                 ad.u.net.sport = htons(snum);
3752                                 ad.u.net.family = family;
3753                                 err = avc_has_perm(isec->sid, sid,
3754                                                    isec->sclass,
3755                                                    SOCKET__NAME_BIND, &ad);
3756                                 if (err)
3757                                         goto out;
3758                         }
3759                 }
3760
3761                 switch (isec->sclass) {
3762                 case SECCLASS_TCP_SOCKET:
3763                         node_perm = TCP_SOCKET__NODE_BIND;
3764                         break;
3765
3766                 case SECCLASS_UDP_SOCKET:
3767                         node_perm = UDP_SOCKET__NODE_BIND;
3768                         break;
3769
3770                 case SECCLASS_DCCP_SOCKET:
3771                         node_perm = DCCP_SOCKET__NODE_BIND;
3772                         break;
3773
3774                 default:
3775                         node_perm = RAWIP_SOCKET__NODE_BIND;
3776                         break;
3777                 }
3778
3779                 err = sel_netnode_sid(addrp, family, &sid);
3780                 if (err)
3781                         goto out;
3782
3783                 AVC_AUDIT_DATA_INIT(&ad, NET);
3784                 ad.u.net.sport = htons(snum);
3785                 ad.u.net.family = family;
3786
3787                 if (family == PF_INET)
3788                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3789                 else
3790                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3791
3792                 err = avc_has_perm(isec->sid, sid,
3793                                    isec->sclass, node_perm, &ad);
3794                 if (err)
3795                         goto out;
3796         }
3797 out:
3798         return err;
3799 }
3800
3801 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3802 {
3803         struct inode_security_struct *isec;
3804         int err;
3805
3806         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3807         if (err)
3808                 return err;
3809
3810         /*
3811          * If a TCP or DCCP socket, check name_connect permission for the port.
3812          */
3813         isec = SOCK_INODE(sock)->i_security;
3814         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3815             isec->sclass == SECCLASS_DCCP_SOCKET) {
3816                 struct sock *sk = sock->sk;
3817                 struct avc_audit_data ad;
3818                 struct sockaddr_in *addr4 = NULL;
3819                 struct sockaddr_in6 *addr6 = NULL;
3820                 unsigned short snum;
3821                 u32 sid, perm;
3822
3823                 if (sk->sk_family == PF_INET) {
3824                         addr4 = (struct sockaddr_in *)address;
3825                         if (addrlen < sizeof(struct sockaddr_in))
3826                                 return -EINVAL;
3827                         snum = ntohs(addr4->sin_port);
3828                 } else {
3829                         addr6 = (struct sockaddr_in6 *)address;
3830                         if (addrlen < SIN6_LEN_RFC2133)
3831                                 return -EINVAL;
3832                         snum = ntohs(addr6->sin6_port);
3833                 }
3834
3835                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3836                 if (err)
3837                         goto out;
3838
3839                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3840                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3841
3842                 AVC_AUDIT_DATA_INIT(&ad, NET);
3843                 ad.u.net.dport = htons(snum);
3844                 ad.u.net.family = sk->sk_family;
3845                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3846                 if (err)
3847                         goto out;
3848         }
3849
3850 out:
3851         return err;
3852 }
3853
3854 static int selinux_socket_listen(struct socket *sock, int backlog)
3855 {
3856         return socket_has_perm(current, sock, SOCKET__LISTEN);
3857 }
3858
3859 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3860 {
3861         int err;
3862         struct inode_security_struct *isec;
3863         struct inode_security_struct *newisec;
3864
3865         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3866         if (err)
3867                 return err;
3868
3869         newisec = SOCK_INODE(newsock)->i_security;
3870
3871         isec = SOCK_INODE(sock)->i_security;
3872         newisec->sclass = isec->sclass;
3873         newisec->sid = isec->sid;
3874         newisec->initialized = 1;
3875
3876         return 0;
3877 }
3878
3879 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3880                                   int size)
3881 {
3882         int rc;
3883
3884         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3885         if (rc)
3886                 return rc;
3887
3888         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3889 }
3890
3891 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3892                                   int size, int flags)
3893 {
3894         return socket_has_perm(current, sock, SOCKET__READ);
3895 }
3896
3897 static int selinux_socket_getsockname(struct socket *sock)
3898 {
3899         return socket_has_perm(current, sock, SOCKET__GETATTR);
3900 }
3901
3902 static int selinux_socket_getpeername(struct socket *sock)
3903 {
3904         return socket_has_perm(current, sock, SOCKET__GETATTR);
3905 }
3906
3907 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3908 {
3909         int err;
3910
3911         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3912         if (err)
3913                 return err;
3914
3915         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3916 }
3917
3918 static int selinux_socket_getsockopt(struct socket *sock, int level,
3919                                      int optname)
3920 {
3921         return socket_has_perm(current, sock, SOCKET__GETOPT);
3922 }
3923
3924 static int selinux_socket_shutdown(struct socket *sock, int how)
3925 {
3926         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3927 }
3928
3929 static int selinux_socket_unix_stream_connect(struct socket *sock,
3930                                               struct socket *other,
3931                                               struct sock *newsk)
3932 {
3933         struct sk_security_struct *ssec;
3934         struct inode_security_struct *isec;
3935         struct inode_security_struct *other_isec;
3936         struct avc_audit_data ad;
3937         int err;
3938
3939         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3940         if (err)
3941                 return err;
3942
3943         isec = SOCK_INODE(sock)->i_security;
3944         other_isec = SOCK_INODE(other)->i_security;
3945
3946         AVC_AUDIT_DATA_INIT(&ad, NET);
3947         ad.u.net.sk = other->sk;
3948
3949         err = avc_has_perm(isec->sid, other_isec->sid,
3950                            isec->sclass,
3951                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3952         if (err)
3953                 return err;
3954
3955         /* connecting socket */
3956         ssec = sock->sk->sk_security;
3957         ssec->peer_sid = other_isec->sid;
3958
3959         /* server child socket */
3960         ssec = newsk->sk_security;
3961         ssec->peer_sid = isec->sid;
3962         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3963
3964         return err;
3965 }
3966
3967 static int selinux_socket_unix_may_send(struct socket *sock,
3968                                         struct socket *other)
3969 {
3970         struct inode_security_struct *isec;
3971         struct inode_security_struct *other_isec;
3972         struct avc_audit_data ad;
3973         int err;
3974
3975         isec = SOCK_INODE(sock)->i_security;
3976         other_isec = SOCK_INODE(other)->i_security;
3977
3978         AVC_AUDIT_DATA_INIT(&ad, NET);
3979         ad.u.net.sk = other->sk;
3980
3981         err = avc_has_perm(isec->sid, other_isec->sid,
3982                            isec->sclass, SOCKET__SENDTO, &ad);
3983         if (err)
3984                 return err;
3985
3986         return 0;
3987 }
3988
3989 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3990                                     u32 peer_sid,
3991                                     struct avc_audit_data *ad)
3992 {
3993         int err;
3994         u32 if_sid;
3995         u32 node_sid;
3996
3997         err = sel_netif_sid(ifindex, &if_sid);
3998         if (err)
3999                 return err;
4000         err = avc_has_perm(peer_sid, if_sid,
4001                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4002         if (err)
4003                 return err;
4004
4005         err = sel_netnode_sid(addrp, family, &node_sid);
4006         if (err)
4007                 return err;
4008         return avc_has_perm(peer_sid, node_sid,
4009                             SECCLASS_NODE, NODE__RECVFROM, ad);
4010 }
4011
4012 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4013                                                 struct sk_buff *skb,
4014                                                 struct avc_audit_data *ad,
4015                                                 u16 family,
4016                                                 char *addrp)
4017 {
4018         int err;
4019         struct sk_security_struct *sksec = sk->sk_security;
4020         u16 sk_class;
4021         u32 netif_perm, node_perm, recv_perm;
4022         u32 port_sid, node_sid, if_sid, sk_sid;
4023
4024         sk_sid = sksec->sid;
4025         sk_class = sksec->sclass;
4026
4027         switch (sk_class) {
4028         case SECCLASS_UDP_SOCKET:
4029                 netif_perm = NETIF__UDP_RECV;
4030                 node_perm = NODE__UDP_RECV;
4031                 recv_perm = UDP_SOCKET__RECV_MSG;
4032                 break;
4033         case SECCLASS_TCP_SOCKET:
4034                 netif_perm = NETIF__TCP_RECV;
4035                 node_perm = NODE__TCP_RECV;
4036                 recv_perm = TCP_SOCKET__RECV_MSG;
4037                 break;
4038         case SECCLASS_DCCP_SOCKET:
4039                 netif_perm = NETIF__DCCP_RECV;
4040                 node_perm = NODE__DCCP_RECV;
4041                 recv_perm = DCCP_SOCKET__RECV_MSG;
4042                 break;
4043         default:
4044                 netif_perm = NETIF__RAWIP_RECV;
4045                 node_perm = NODE__RAWIP_RECV;
4046                 recv_perm = 0;
4047                 break;
4048         }
4049
4050         err = sel_netif_sid(skb->iif, &if_sid);
4051         if (err)
4052                 return err;
4053         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4054         if (err)
4055                 return err;
4056
4057         err = sel_netnode_sid(addrp, family, &node_sid);
4058         if (err)
4059                 return err;
4060         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4061         if (err)
4062                 return err;
4063
4064         if (!recv_perm)
4065                 return 0;
4066         err = sel_netport_sid(sk->sk_protocol,
4067                               ntohs(ad->u.net.sport), &port_sid);
4068         if (unlikely(err)) {
4069                 printk(KERN_WARNING
4070                        "SELinux: failure in"
4071                        " selinux_sock_rcv_skb_iptables_compat(),"
4072                        " network port label not found\n");
4073                 return err;
4074         }
4075         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4076 }
4077
4078 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4079                                        struct avc_audit_data *ad,
4080                                        u16 family, char *addrp)
4081 {
4082         int err;
4083         struct sk_security_struct *sksec = sk->sk_security;
4084         u32 peer_sid;
4085         u32 sk_sid = sksec->sid;
4086
4087         if (selinux_compat_net)
4088                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
4089                                                            family, addrp);
4090         else
4091                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4092                                    PACKET__RECV, ad);
4093         if (err)
4094                 return err;
4095
4096         if (selinux_policycap_netpeer) {
4097                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4098                 if (err)
4099                         return err;
4100                 err = avc_has_perm(sk_sid, peer_sid,
4101                                    SECCLASS_PEER, PEER__RECV, ad);
4102         } else {
4103                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
4104                 if (err)
4105                         return err;
4106                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
4107         }
4108
4109         return err;
4110 }
4111
4112 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4113 {
4114         int err;
4115         struct sk_security_struct *sksec = sk->sk_security;
4116         u16 family = sk->sk_family;
4117         u32 sk_sid = sksec->sid;
4118         struct avc_audit_data ad;
4119         char *addrp;
4120
4121         if (family != PF_INET && family != PF_INET6)
4122                 return 0;
4123
4124         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4125         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4126                 family = PF_INET;
4127
4128         AVC_AUDIT_DATA_INIT(&ad, NET);
4129         ad.u.net.netif = skb->iif;
4130         ad.u.net.family = family;
4131         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4132         if (err)
4133                 return err;
4134
4135         /* If any sort of compatibility mode is enabled then handoff processing
4136          * to the selinux_sock_rcv_skb_compat() function to deal with the
4137          * special handling.  We do this in an attempt to keep this function
4138          * as fast and as clean as possible. */
4139         if (selinux_compat_net || !selinux_policycap_netpeer)
4140                 return selinux_sock_rcv_skb_compat(sk, skb, &ad,
4141                                                    family, addrp);
4142
4143         if (netlbl_enabled() || selinux_xfrm_enabled()) {
4144                 u32 peer_sid;
4145
4146                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4147                 if (err)
4148                         return err;
4149                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4150                                                peer_sid, &ad);
4151                 if (err)
4152                         return err;
4153                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4154                                    PEER__RECV, &ad);
4155         }
4156
4157         if (selinux_secmark_enabled()) {
4158                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4159                                    PACKET__RECV, &ad);
4160                 if (err)
4161                         return err;
4162         }
4163
4164         return err;
4165 }
4166
4167 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4168                                             int __user *optlen, unsigned len)
4169 {
4170         int err = 0;
4171         char *scontext;
4172         u32 scontext_len;
4173         struct sk_security_struct *ssec;
4174         struct inode_security_struct *isec;
4175         u32 peer_sid = SECSID_NULL;
4176
4177         isec = SOCK_INODE(sock)->i_security;
4178
4179         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4180             isec->sclass == SECCLASS_TCP_SOCKET) {
4181                 ssec = sock->sk->sk_security;
4182                 peer_sid = ssec->peer_sid;
4183         }
4184         if (peer_sid == SECSID_NULL) {
4185                 err = -ENOPROTOOPT;
4186                 goto out;
4187         }
4188
4189         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4190
4191         if (err)
4192                 goto out;
4193
4194         if (scontext_len > len) {
4195                 err = -ERANGE;
4196                 goto out_len;
4197         }
4198
4199         if (copy_to_user(optval, scontext, scontext_len))
4200                 err = -EFAULT;
4201
4202 out_len:
4203         if (put_user(scontext_len, optlen))
4204                 err = -EFAULT;
4205
4206         kfree(scontext);
4207 out:
4208         return err;
4209 }
4210
4211 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4212 {
4213         u32 peer_secid = SECSID_NULL;
4214         u16 family;
4215
4216         if (sock)
4217                 family = sock->sk->sk_family;
4218         else if (skb && skb->sk)
4219                 family = skb->sk->sk_family;
4220         else
4221                 goto out;
4222
4223         if (sock && family == PF_UNIX)
4224                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4225         else if (skb)
4226                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4227
4228 out:
4229         *secid = peer_secid;
4230         if (peer_secid == SECSID_NULL)
4231                 return -EINVAL;
4232         return 0;
4233 }
4234
4235 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4236 {
4237         return sk_alloc_security(sk, family, priority);
4238 }
4239
4240 static void selinux_sk_free_security(struct sock *sk)
4241 {
4242         sk_free_security(sk);
4243 }
4244
4245 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4246 {
4247         struct sk_security_struct *ssec = sk->sk_security;
4248         struct sk_security_struct *newssec = newsk->sk_security;
4249
4250         newssec->sid = ssec->sid;
4251         newssec->peer_sid = ssec->peer_sid;
4252         newssec->sclass = ssec->sclass;
4253
4254         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4255 }
4256
4257 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4258 {
4259         if (!sk)
4260                 *secid = SECINITSID_ANY_SOCKET;
4261         else {
4262                 struct sk_security_struct *sksec = sk->sk_security;
4263
4264                 *secid = sksec->sid;
4265         }
4266 }
4267
4268 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4269 {
4270         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4271         struct sk_security_struct *sksec = sk->sk_security;
4272
4273         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4274             sk->sk_family == PF_UNIX)
4275                 isec->sid = sksec->sid;
4276         sksec->sclass = isec->sclass;
4277
4278         selinux_netlbl_sock_graft(sk, parent);
4279 }
4280
4281 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4282                                      struct request_sock *req)
4283 {
4284         struct sk_security_struct *sksec = sk->sk_security;
4285         int err;
4286         u32 newsid;
4287         u32 peersid;
4288
4289         err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
4290         if (err)
4291                 return err;
4292         if (peersid == SECSID_NULL) {
4293                 req->secid = sksec->sid;
4294                 req->peer_secid = SECSID_NULL;
4295                 return 0;
4296         }
4297
4298         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4299         if (err)
4300                 return err;
4301
4302         req->secid = newsid;
4303         req->peer_secid = peersid;
4304         return 0;
4305 }
4306
4307 static void selinux_inet_csk_clone(struct sock *newsk,
4308                                    const struct request_sock *req)
4309 {
4310         struct sk_security_struct *newsksec = newsk->sk_security;
4311
4312         newsksec->sid = req->secid;
4313         newsksec->peer_sid = req->peer_secid;
4314         /* NOTE: Ideally, we should also get the isec->sid for the
4315            new socket in sync, but we don't have the isec available yet.
4316            So we will wait until sock_graft to do it, by which
4317            time it will have been created and available. */
4318
4319         /* We don't need to take any sort of lock here as we are the only
4320          * thread with access to newsksec */
4321         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4322 }
4323
4324 static void selinux_inet_conn_established(struct sock *sk,
4325                                 struct sk_buff *skb)
4326 {
4327         struct sk_security_struct *sksec = sk->sk_security;
4328
4329         selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
4330 }
4331
4332 static void selinux_req_classify_flow(const struct request_sock *req,
4333                                       struct flowi *fl)
4334 {
4335         fl->secid = req->secid;
4336 }
4337
4338 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4339 {
4340         int err = 0;
4341         u32 perm;
4342         struct nlmsghdr *nlh;
4343         struct socket *sock = sk->sk_socket;
4344         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4345
4346         if (skb->len < NLMSG_SPACE(0)) {
4347                 err = -EINVAL;
4348                 goto out;
4349         }
4350         nlh = nlmsg_hdr(skb);
4351
4352         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4353         if (err) {
4354                 if (err == -EINVAL) {
4355                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4356                                   "SELinux:  unrecognized netlink message"
4357                                   " type=%hu for sclass=%hu\n",
4358                                   nlh->nlmsg_type, isec->sclass);
4359                         if (!selinux_enforcing)
4360                                 err = 0;
4361                 }
4362
4363                 /* Ignore */
4364                 if (err == -ENOENT)
4365                         err = 0;
4366                 goto out;
4367         }
4368
4369         err = socket_has_perm(current, sock, perm);
4370 out:
4371         return err;
4372 }
4373
4374 #ifdef CONFIG_NETFILTER
4375
4376 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4377                                        u16 family)
4378 {
4379         char *addrp;
4380         u32 peer_sid;
4381         struct avc_audit_data ad;
4382         u8 secmark_active;
4383         u8 peerlbl_active;
4384
4385         if (!selinux_policycap_netpeer)
4386                 return NF_ACCEPT;
4387
4388         secmark_active = selinux_secmark_enabled();
4389         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4390         if (!secmark_active && !peerlbl_active)
4391                 return NF_ACCEPT;
4392
4393         AVC_AUDIT_DATA_INIT(&ad, NET);
4394         ad.u.net.netif = ifindex;
4395         ad.u.net.family = family;
4396         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4397                 return NF_DROP;
4398
4399         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4400                 return NF_DROP;
4401
4402         if (peerlbl_active)
4403                 if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4404                                              peer_sid, &ad) != 0)
4405                         return NF_DROP;
4406
4407         if (secmark_active)
4408                 if (avc_has_perm(peer_sid, skb->secmark,
4409                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4410                         return NF_DROP;
4411
4412         return NF_ACCEPT;
4413 }
4414
4415 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4416                                          struct sk_buff *skb,
4417                                          const struct net_device *in,
4418                                          const struct net_device *out,
4419                                          int (*okfn)(struct sk_buff *))
4420 {
4421         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4422 }
4423
4424 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4425 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4426                                          struct sk_buff *skb,
4427                                          const struct net_device *in,
4428                                          const struct net_device *out,
4429                                          int (*okfn)(struct sk_buff *))
4430 {
4431         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4432 }
4433 #endif  /* IPV6 */
4434
4435 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4436                                                 int ifindex,
4437                                                 struct avc_audit_data *ad,
4438                                                 u16 family, char *addrp)
4439 {
4440         int err;
4441         struct sk_security_struct *sksec = sk->sk_security;
4442         u16 sk_class;
4443         u32 netif_perm, node_perm, send_perm;
4444         u32 port_sid, node_sid, if_sid, sk_sid;
4445
4446         sk_sid = sksec->sid;
4447         sk_class = sksec->sclass;
4448
4449         switch (sk_class) {
4450         case SECCLASS_UDP_SOCKET:
4451                 netif_perm = NETIF__UDP_SEND;
4452                 node_perm = NODE__UDP_SEND;
4453                 send_perm = UDP_SOCKET__SEND_MSG;
4454                 break;
4455         case SECCLASS_TCP_SOCKET:
4456                 netif_perm = NETIF__TCP_SEND;
4457                 node_perm = NODE__TCP_SEND;
4458                 send_perm = TCP_SOCKET__SEND_MSG;
4459                 break;
4460         case SECCLASS_DCCP_SOCKET:
4461                 netif_perm = NETIF__DCCP_SEND;
4462                 node_perm = NODE__DCCP_SEND;
4463                 send_perm = DCCP_SOCKET__SEND_MSG;
4464                 break;
4465         default:
4466                 netif_perm = NETIF__RAWIP_SEND;
4467                 node_perm = NODE__RAWIP_SEND;
4468                 send_perm = 0;
4469                 break;
4470         }
4471
4472         err = sel_netif_sid(ifindex, &if_sid);
4473         if (err)
4474                 return err;
4475         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4476                 return err;
4477
4478         err = sel_netnode_sid(addrp, family, &node_sid);
4479         if (err)
4480                 return err;
4481         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4482         if (err)
4483                 return err;
4484
4485         if (send_perm != 0)
4486                 return 0;
4487
4488         err = sel_netport_sid(sk->sk_protocol,
4489                               ntohs(ad->u.net.dport), &port_sid);
4490         if (unlikely(err)) {
4491                 printk(KERN_WARNING
4492                        "SELinux: failure in"
4493                        " selinux_ip_postroute_iptables_compat(),"
4494                        " network port label not found\n");
4495                 return err;
4496         }
4497         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4498 }
4499
4500 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4501                                                 int ifindex,
4502                                                 struct avc_audit_data *ad,
4503                                                 u16 family,
4504                                                 char *addrp,
4505                                                 u8 proto)
4506 {
4507         struct sock *sk = skb->sk;
4508         struct sk_security_struct *sksec;
4509
4510         if (sk == NULL)
4511                 return NF_ACCEPT;
4512         sksec = sk->sk_security;
4513
4514         if (selinux_compat_net) {
4515                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4516                                                          ad, family, addrp))
4517                         return NF_DROP;
4518         } else {
4519                 if (avc_has_perm(sksec->sid, skb->secmark,
4520                                  SECCLASS_PACKET, PACKET__SEND, ad))
4521                         return NF_DROP;
4522         }
4523
4524         if (selinux_policycap_netpeer)
4525                 if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto))
4526                         return NF_DROP;
4527
4528         return NF_ACCEPT;
4529 }
4530
4531 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4532                                          u16 family)
4533 {
4534         u32 secmark_perm;
4535         u32 peer_sid;
4536         struct sock *sk;
4537         struct avc_audit_data ad;
4538         char *addrp;
4539         u8 proto;
4540         u8 secmark_active;
4541         u8 peerlbl_active;
4542
4543         AVC_AUDIT_DATA_INIT(&ad, NET);
4544         ad.u.net.netif = ifindex;
4545         ad.u.net.family = family;
4546         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4547                 return NF_DROP;
4548
4549         /* If any sort of compatibility mode is enabled then handoff processing
4550          * to the selinux_ip_postroute_compat() function to deal with the
4551          * special handling.  We do this in an attempt to keep this function
4552          * as fast and as clean as possible. */
4553         if (selinux_compat_net || !selinux_policycap_netpeer)
4554                 return selinux_ip_postroute_compat(skb, ifindex, &ad,
4555                                                    family, addrp, proto);
4556
4557         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4558          * packet transformation so allow the packet to pass without any checks
4559          * since we'll have another chance to perform access control checks
4560          * when the packet is on it's final way out.
4561          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4562          *       is NULL, in this case go ahead and apply access control. */
4563         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4564                 return NF_ACCEPT;
4565
4566         secmark_active = selinux_secmark_enabled();
4567         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4568         if (!secmark_active && !peerlbl_active)
4569                 return NF_ACCEPT;
4570
4571         /* if the packet is locally generated (skb->sk != NULL) then use the
4572          * socket's label as the peer label, otherwise the packet is being
4573          * forwarded through this system and we need to fetch the peer label
4574          * directly from the packet */
4575         sk = skb->sk;
4576         if (sk) {
4577                 struct sk_security_struct *sksec = sk->sk_security;
4578                 peer_sid = sksec->sid;
4579                 secmark_perm = PACKET__SEND;
4580         } else {
4581                 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4582                                 return NF_DROP;
4583                 secmark_perm = PACKET__FORWARD_OUT;
4584         }
4585
4586         if (secmark_active)
4587                 if (avc_has_perm(peer_sid, skb->secmark,
4588                                  SECCLASS_PACKET, secmark_perm, &ad))
4589                         return NF_DROP;
4590
4591         if (peerlbl_active) {
4592                 u32 if_sid;
4593                 u32 node_sid;
4594
4595                 if (sel_netif_sid(ifindex, &if_sid))
4596                         return NF_DROP;
4597                 if (avc_has_perm(peer_sid, if_sid,
4598                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4599                         return NF_DROP;
4600
4601                 if (sel_netnode_sid(addrp, family, &node_sid))
4602                         return NF_DROP;
4603                 if (avc_has_perm(peer_sid, node_sid,
4604                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4605                         return NF_DROP;
4606         }
4607
4608         return NF_ACCEPT;
4609 }
4610
4611 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4612                                            struct sk_buff *skb,
4613                                            const struct net_device *in,
4614                                            const struct net_device *out,
4615                                            int (*okfn)(struct sk_buff *))
4616 {
4617         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4618 }
4619
4620 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4621 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4622                                            struct sk_buff *skb,
4623                                            const struct net_device *in,
4624                                            const struct net_device *out,
4625                                            int (*okfn)(struct sk_buff *))
4626 {
4627         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4628 }
4629 #endif  /* IPV6 */
4630
4631 #endif  /* CONFIG_NETFILTER */
4632
4633 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4634 {
4635         int err;
4636
4637         err = secondary_ops->netlink_send(sk, skb);
4638         if (err)
4639                 return err;
4640
4641         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4642                 err = selinux_nlmsg_perm(sk, skb);
4643
4644         return err;
4645 }
4646
4647 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4648 {
4649         int err;
4650         struct avc_audit_data ad;
4651
4652         err = secondary_ops->netlink_recv(skb, capability);
4653         if (err)
4654                 return err;
4655
4656         AVC_AUDIT_DATA_INIT(&ad, CAP);
4657         ad.u.cap = capability;
4658
4659         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4660                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4661 }
4662
4663 static int ipc_alloc_security(struct task_struct *task,
4664                               struct kern_ipc_perm *perm,
4665                               u16 sclass)
4666 {
4667         struct task_security_struct *tsec = task->security;
4668         struct ipc_security_struct *isec;
4669
4670         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4671         if (!isec)
4672                 return -ENOMEM;
4673
4674         isec->sclass = sclass;
4675         isec->sid = tsec->sid;
4676         perm->security = isec;
4677
4678         return 0;
4679 }
4680
4681 static void ipc_free_security(struct kern_ipc_perm *perm)
4682 {
4683         struct ipc_security_struct *isec = perm->security;
4684         perm->security = NULL;
4685         kfree(isec);
4686 }
4687
4688 static int msg_msg_alloc_security(struct msg_msg *msg)
4689 {
4690         struct msg_security_struct *msec;
4691
4692         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4693         if (!msec)
4694                 return -ENOMEM;
4695
4696         msec->sid = SECINITSID_UNLABELED;
4697         msg->security = msec;
4698
4699         return 0;
4700 }
4701
4702 static void msg_msg_free_security(struct msg_msg *msg)
4703 {
4704         struct msg_security_struct *msec = msg->security;
4705
4706         msg->security = NULL;
4707         kfree(msec);
4708 }
4709
4710 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4711                         u32 perms)
4712 {
4713         struct task_security_struct *tsec;
4714         struct ipc_security_struct *isec;
4715         struct avc_audit_data ad;
4716
4717         tsec = current->security;
4718         isec = ipc_perms->security;
4719
4720         AVC_AUDIT_DATA_INIT(&ad, IPC);
4721         ad.u.ipc_id = ipc_perms->key;
4722
4723         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
4724 }
4725
4726 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4727 {
4728         return msg_msg_alloc_security(msg);
4729 }
4730
4731 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4732 {
4733         msg_msg_free_security(msg);
4734 }
4735
4736 /* message queue security operations */
4737 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4738 {
4739         struct task_security_struct *tsec;
4740         struct ipc_security_struct *isec;
4741         struct avc_audit_data ad;
4742         int rc;
4743
4744         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4745         if (rc)
4746                 return rc;
4747
4748         tsec = current->security;
4749         isec = msq->q_perm.security;
4750
4751         AVC_AUDIT_DATA_INIT(&ad, IPC);
4752         ad.u.ipc_id = msq->q_perm.key;
4753
4754         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4755                           MSGQ__CREATE, &ad);
4756         if (rc) {
4757                 ipc_free_security(&msq->q_perm);
4758                 return rc;
4759         }
4760         return 0;
4761 }
4762
4763 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4764 {
4765         ipc_free_security(&msq->q_perm);
4766 }
4767
4768 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4769 {
4770         struct task_security_struct *tsec;
4771         struct ipc_security_struct *isec;
4772         struct avc_audit_data ad;
4773
4774         tsec = current->security;
4775         isec = msq->q_perm.security;
4776
4777         AVC_AUDIT_DATA_INIT(&ad, IPC);
4778         ad.u.ipc_id = msq->q_perm.key;
4779
4780         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4781                             MSGQ__ASSOCIATE, &ad);
4782 }
4783
4784 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4785 {
4786         int err;
4787         int perms;
4788
4789         switch (cmd) {
4790         case IPC_INFO:
4791         case MSG_INFO:
4792                 /* No specific object, just general system-wide information. */
4793                 return task_has_system(current, SYSTEM__IPC_INFO);
4794         case IPC_STAT:
4795         case MSG_STAT:
4796                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4797                 break;
4798         case IPC_SET:
4799                 perms = MSGQ__SETATTR;
4800                 break;
4801         case IPC_RMID:
4802                 perms = MSGQ__DESTROY;
4803                 break;
4804         default:
4805                 return 0;
4806         }
4807
4808         err = ipc_has_perm(&msq->q_perm, perms);
4809         return err;
4810 }
4811
4812 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4813 {
4814         struct task_security_struct *tsec;
4815         struct ipc_security_struct *isec;
4816         struct msg_security_struct *msec;
4817         struct avc_audit_data ad;
4818         int rc;
4819
4820         tsec = current->security;
4821         isec = msq->q_perm.security;
4822         msec = msg->security;
4823
4824         /*
4825          * First time through, need to assign label to the message
4826          */
4827         if (msec->sid == SECINITSID_UNLABELED) {
4828                 /*
4829                  * Compute new sid based on current process and
4830                  * message queue this message will be stored in
4831                  */
4832                 rc = security_transition_sid(tsec->sid,
4833                                              isec->sid,
4834                                              SECCLASS_MSG,
4835                                              &msec->sid);
4836                 if (rc)
4837                         return rc;
4838         }
4839
4840         AVC_AUDIT_DATA_INIT(&ad, IPC);
4841         ad.u.ipc_id = msq->q_perm.key;
4842
4843         /* Can this process write to the queue? */
4844         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4845                           MSGQ__WRITE, &ad);
4846         if (!rc)
4847                 /* Can this process send the message */
4848                 rc = avc_has_perm(tsec->sid, msec->sid,
4849                                   SECCLASS_MSG, MSG__SEND, &ad);
4850         if (!rc)
4851                 /* Can the message be put in the queue? */
4852                 rc = avc_has_perm(msec->sid, isec->sid,
4853                                   SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
4854
4855         return rc;
4856 }
4857
4858 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4859                                     struct task_struct *target,
4860                                     long type, int mode)
4861 {
4862         struct task_security_struct *tsec;
4863         struct ipc_security_struct *isec;
4864         struct msg_security_struct *msec;
4865         struct avc_audit_data ad;
4866         int rc;
4867
4868         tsec = target->security;
4869         isec = msq->q_perm.security;
4870         msec = msg->security;
4871
4872         AVC_AUDIT_DATA_INIT(&ad, IPC);
4873         ad.u.ipc_id = msq->q_perm.key;
4874
4875         rc = avc_has_perm(tsec->sid, isec->sid,
4876                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4877         if (!rc)
4878                 rc = avc_has_perm(tsec->sid, msec->sid,
4879                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4880         return rc;
4881 }
4882
4883 /* Shared Memory security operations */
4884 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4885 {
4886         struct task_security_struct *tsec;
4887         struct ipc_security_struct *isec;
4888         struct avc_audit_data ad;
4889         int rc;
4890
4891         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4892         if (rc)
4893                 return rc;
4894
4895         tsec = current->security;
4896         isec = shp->shm_perm.security;
4897
4898         AVC_AUDIT_DATA_INIT(&ad, IPC);
4899         ad.u.ipc_id = shp->shm_perm.key;
4900
4901         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4902                           SHM__CREATE, &ad);
4903         if (rc) {
4904                 ipc_free_security(&shp->shm_perm);
4905                 return rc;
4906         }
4907         return 0;
4908 }
4909
4910 static void selinux_shm_free_security(struct shmid_kernel *shp)
4911 {
4912         ipc_free_security(&shp->shm_perm);
4913 }
4914
4915 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4916 {
4917         struct task_security_struct *tsec;
4918         struct ipc_security_struct *isec;
4919         struct avc_audit_data ad;
4920
4921         tsec = current->security;
4922         isec = shp->shm_perm.security;
4923
4924         AVC_AUDIT_DATA_INIT(&ad, IPC);
4925         ad.u.ipc_id = shp->shm_perm.key;
4926
4927         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4928                             SHM__ASSOCIATE, &ad);
4929 }
4930
4931 /* Note, at this point, shp is locked down */
4932 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4933 {
4934         int perms;
4935         int err;
4936
4937         switch (cmd) {
4938         case IPC_INFO:
4939         case SHM_INFO:
4940                 /* No specific object, just general system-wide information. */
4941                 return task_has_system(current, SYSTEM__IPC_INFO);
4942         case IPC_STAT:
4943         case SHM_STAT:
4944                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4945                 break;
4946         case IPC_SET:
4947                 perms = SHM__SETATTR;
4948                 break;
4949         case SHM_LOCK:
4950         case SHM_UNLOCK:
4951                 perms = SHM__LOCK;
4952                 break;
4953         case IPC_RMID:
4954                 perms = SHM__DESTROY;
4955                 break;
4956         default:
4957                 return 0;
4958         }
4959
4960         err = ipc_has_perm(&shp->shm_perm, perms);
4961         return err;
4962 }
4963
4964 static int selinux_shm_shmat(struct shmid_kernel *shp,
4965                              char __user *shmaddr, int shmflg)
4966 {
4967         u32 perms;
4968         int rc;
4969
4970         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
4971         if (rc)
4972                 return rc;
4973
4974         if (shmflg & SHM_RDONLY)
4975                 perms = SHM__READ;
4976         else
4977                 perms = SHM__READ | SHM__WRITE;
4978
4979         return ipc_has_perm(&shp->shm_perm, perms);
4980 }
4981
4982 /* Semaphore security operations */
4983 static int selinux_sem_alloc_security(struct sem_array *sma)
4984 {
4985         struct task_security_struct *tsec;
4986         struct ipc_security_struct *isec;
4987         struct avc_audit_data ad;
4988         int rc;
4989
4990         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4991         if (rc)
4992                 return rc;
4993
4994         tsec = current->security;
4995         isec = sma->sem_perm.security;
4996
4997         AVC_AUDIT_DATA_INIT(&ad, IPC);
4998         ad.u.ipc_id = sma->sem_perm.key;
4999
5000         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
5001                           SEM__CREATE, &ad);
5002         if (rc) {
5003                 ipc_free_security(&sma->sem_perm);
5004                 return rc;
5005         }
5006         return 0;
5007 }
5008
5009 static void selinux_sem_free_security(struct sem_array *sma)
5010 {
5011         ipc_free_security(&sma->sem_perm);
5012 }
5013
5014 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5015 {
5016         struct task_security_struct *tsec;
5017         struct ipc_security_struct *isec;
5018         struct avc_audit_data ad;
5019
5020         tsec = current->security;
5021         isec = sma->sem_perm.security;
5022
5023         AVC_AUDIT_DATA_INIT(&ad, IPC);
5024         ad.u.ipc_id = sma->sem_perm.key;
5025
5026         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
5027                             SEM__ASSOCIATE, &ad);
5028 }
5029
5030 /* Note, at this point, sma is locked down */
5031 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5032 {
5033         int err;
5034         u32 perms;
5035
5036         switch (cmd) {
5037         case IPC_INFO:
5038         case SEM_INFO:
5039                 /* No specific object, just general system-wide information. */
5040                 return task_has_system(current, SYSTEM__IPC_INFO);
5041         case GETPID:
5042         case GETNCNT:
5043         case GETZCNT:
5044                 perms = SEM__GETATTR;
5045                 break;
5046         case GETVAL:
5047         case GETALL:
5048                 perms = SEM__READ;
5049                 break;
5050         case SETVAL:
5051         case SETALL:
5052                 perms = SEM__WRITE;
5053                 break;
5054         case IPC_RMID:
5055                 perms = SEM__DESTROY;
5056                 break;
5057         case IPC_SET:
5058                 perms = SEM__SETATTR;
5059                 break;
5060         case IPC_STAT:
5061         case SEM_STAT:
5062                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5063                 break;
5064         default:
5065                 return 0;
5066         }
5067
5068         err = ipc_has_perm(&sma->sem_perm, perms);
5069         return err;
5070 }
5071
5072 static int selinux_sem_semop(struct sem_array *sma,
5073                              struct sembuf *sops, unsigned nsops, int alter)
5074 {
5075         u32 perms;
5076
5077         if (alter)
5078                 perms = SEM__READ | SEM__WRITE;
5079         else
5080                 perms = SEM__READ;
5081
5082         return ipc_has_perm(&sma->sem_perm, perms);
5083 }
5084
5085 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5086 {
5087         u32 av = 0;
5088
5089         av = 0;
5090         if (flag & S_IRUGO)
5091                 av |= IPC__UNIX_READ;
5092         if (flag & S_IWUGO)
5093                 av |= IPC__UNIX_WRITE;
5094
5095         if (av == 0)
5096                 return 0;
5097
5098         return ipc_has_perm(ipcp, av);
5099 }
5100
5101 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5102 {
5103         struct ipc_security_struct *isec = ipcp->security;
5104         *secid = isec->sid;
5105 }
5106
5107 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5108 {
5109         if (inode)
5110                 inode_doinit_with_dentry(inode, dentry);
5111 }
5112
5113 static int selinux_getprocattr(struct task_struct *p,
5114                                char *name, char **value)
5115 {
5116         struct task_security_struct *tsec;
5117         u32 sid;
5118         int error;
5119         unsigned len;
5120
5121         if (current != p) {
5122                 error = task_has_perm(current, p, PROCESS__GETATTR);
5123                 if (error)
5124                         return error;
5125         }
5126
5127         tsec = p->security;
5128
5129         if (!strcmp(name, "current"))
5130                 sid = tsec->sid;
5131         else if (!strcmp(name, "prev"))
5132                 sid = tsec->osid;
5133         else if (!strcmp(name, "exec"))
5134                 sid = tsec->exec_sid;
5135         else if (!strcmp(name, "fscreate"))
5136                 sid = tsec->create_sid;
5137         else if (!strcmp(name, "keycreate"))
5138                 sid = tsec->keycreate_sid;
5139         else if (!strcmp(name, "sockcreate"))
5140                 sid = tsec->sockcreate_sid;
5141         else
5142                 return -EINVAL;
5143
5144         if (!sid)
5145                 return 0;
5146
5147         error = security_sid_to_context(sid, value, &len);
5148         if (error)
5149                 return error;
5150         return len;
5151 }
5152
5153 static int selinux_setprocattr(struct task_struct *p,
5154                                char *name, void *value, size_t size)
5155 {
5156         struct task_security_struct *tsec;
5157         struct task_struct *tracer;
5158         u32 sid = 0;
5159         int error;
5160         char *str = value;
5161
5162         if (current != p) {
5163                 /* SELinux only allows a process to change its own
5164                    security attributes. */
5165                 return -EACCES;
5166         }
5167
5168         /*
5169          * Basic control over ability to set these attributes at all.
5170          * current == p, but we'll pass them separately in case the
5171          * above restriction is ever removed.
5172          */
5173         if (!strcmp(name, "exec"))
5174                 error = task_has_perm(current, p, PROCESS__SETEXEC);
5175         else if (!strcmp(name, "fscreate"))
5176                 error = task_has_perm(current, p, PROCESS__SETFSCREATE);
5177         else if (!strcmp(name, "keycreate"))
5178                 error = task_has_perm(current, p, PROCESS__SETKEYCREATE);
5179         else if (!strcmp(name, "sockcreate"))
5180                 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE);
5181         else if (!strcmp(name, "current"))
5182                 error = task_has_perm(current, p, PROCESS__SETCURRENT);
5183         else
5184                 error = -EINVAL;
5185         if (error)
5186                 return error;
5187
5188         /* Obtain a SID for the context, if one was specified. */
5189         if (size && str[1] && str[1] != '\n') {
5190                 if (str[size-1] == '\n') {
5191                         str[size-1] = 0;
5192                         size--;
5193                 }
5194                 error = security_context_to_sid(value, size, &sid);
5195                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5196                         if (!capable(CAP_MAC_ADMIN))
5197                                 return error;
5198                         error = security_context_to_sid_force(value, size,
5199                                                               &sid);
5200                 }
5201                 if (error)
5202                         return error;
5203         }
5204
5205         /* Permission checking based on the specified context is
5206            performed during the actual operation (execve,
5207            open/mkdir/...), when we know the full context of the
5208            operation.  See selinux_bprm_set_security for the execve
5209            checks and may_create for the file creation checks. The
5210            operation will then fail if the context is not permitted. */
5211         tsec = p->security;
5212         if (!strcmp(name, "exec"))
5213                 tsec->exec_sid = sid;
5214         else if (!strcmp(name, "fscreate"))
5215                 tsec->create_sid = sid;
5216         else if (!strcmp(name, "keycreate")) {
5217                 error = may_create_key(sid, p);
5218                 if (error)
5219                         return error;
5220                 tsec->keycreate_sid = sid;
5221         } else if (!strcmp(name, "sockcreate"))
5222                 tsec->sockcreate_sid = sid;
5223         else if (!strcmp(name, "current")) {
5224                 struct av_decision avd;
5225
5226                 if (sid == 0)
5227                         return -EINVAL;
5228                 /*
5229                  * SELinux allows to change context in the following case only.
5230                  *  - Single threaded processes.
5231                  *  - Multi threaded processes intend to change its context into
5232                  *    more restricted domain (defined by TYPEBOUNDS statement).
5233                  */
5234                 if (atomic_read(&p->mm->mm_users) != 1) {
5235                         struct task_struct *g, *t;
5236                         struct mm_struct *mm = p->mm;
5237                         read_lock(&tasklist_lock);
5238                         do_each_thread(g, t) {
5239                                 if (t->mm == mm && t != p) {
5240                                         read_unlock(&tasklist_lock);
5241                                         error = security_bounded_transition(tsec->sid, sid);
5242                                         if (!error)
5243                                                 goto boundary_ok;
5244
5245                                         return error;
5246                                 }
5247                         } while_each_thread(g, t);
5248                         read_unlock(&tasklist_lock);
5249                 }
5250 boundary_ok:
5251
5252                 /* Check permissions for the transition. */
5253                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5254                                      PROCESS__DYNTRANSITION, NULL);
5255                 if (error)
5256                         return error;
5257
5258                 /* Check for ptracing, and update the task SID if ok.
5259                    Otherwise, leave SID unchanged and fail. */
5260                 task_lock(p);
5261                 rcu_read_lock();
5262                 tracer = tracehook_tracer_task(p);
5263                 if (tracer != NULL) {
5264                         struct task_security_struct *ptsec = tracer->security;
5265                         u32 ptsid = ptsec->sid;
5266                         rcu_read_unlock();
5267                         error = avc_has_perm_noaudit(ptsid, sid,
5268                                                      SECCLASS_PROCESS,
5269                                                      PROCESS__PTRACE, 0, &avd);
5270                         if (!error)
5271                                 tsec->sid = sid;
5272                         task_unlock(p);
5273                         avc_audit(ptsid, sid, SECCLASS_PROCESS,
5274                                   PROCESS__PTRACE, &avd, error, NULL);
5275                         if (error)
5276                                 return error;
5277                 } else {
5278                         rcu_read_unlock();
5279                         tsec->sid = sid;
5280                         task_unlock(p);
5281                 }
5282         } else
5283                 return -EINVAL;
5284
5285         return size;
5286 }
5287
5288 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5289 {
5290         return security_sid_to_context(secid, secdata, seclen);
5291 }
5292
5293 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5294 {
5295         return security_context_to_sid(secdata, seclen, secid);
5296 }
5297
5298 static void selinux_release_secctx(char *secdata, u32 seclen)
5299 {
5300         kfree(secdata);
5301 }
5302
5303 #ifdef CONFIG_KEYS
5304
5305 static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
5306                              unsigned long flags)
5307 {
5308         struct task_security_struct *tsec = tsk->security;
5309         struct key_security_struct *ksec;
5310
5311         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5312         if (!ksec)
5313                 return -ENOMEM;
5314
5315         if (tsec->keycreate_sid)
5316                 ksec->sid = tsec->keycreate_sid;
5317         else
5318                 ksec->sid = tsec->sid;
5319         k->security = ksec;
5320
5321         return 0;
5322 }
5323
5324 static void selinux_key_free(struct key *k)
5325 {
5326         struct key_security_struct *ksec = k->security;
5327
5328         k->security = NULL;
5329         kfree(ksec);
5330 }
5331
5332 static int selinux_key_permission(key_ref_t key_ref,
5333                             struct task_struct *ctx,
5334                             key_perm_t perm)
5335 {
5336         struct key *key;
5337         struct task_security_struct *tsec;
5338         struct key_security_struct *ksec;
5339
5340         key = key_ref_to_ptr(key_ref);
5341
5342         tsec = ctx->security;
5343         ksec = key->security;
5344
5345         /* if no specific permissions are requested, we skip the
5346            permission check. No serious, additional covert channels
5347            appear to be created. */
5348         if (perm == 0)
5349                 return 0;
5350
5351         return avc_has_perm(tsec->sid, ksec->sid,
5352                             SECCLASS_KEY, perm, NULL);
5353 }
5354
5355 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5356 {
5357         struct key_security_struct *ksec = key->security;
5358         char *context = NULL;
5359         unsigned len;
5360         int rc;
5361
5362         rc = security_sid_to_context(ksec->sid, &context, &len);
5363         if (!rc)
5364                 rc = len;
5365         *_buffer = context;
5366         return rc;
5367 }
5368
5369 #endif
5370
5371 static struct security_operations selinux_ops = {
5372         .name =                         "selinux",
5373
5374         .ptrace_may_access =            selinux_ptrace_may_access,
5375         .ptrace_traceme =               selinux_ptrace_traceme,
5376         .capget =                       selinux_capget,
5377         .capset_check =                 selinux_capset_check,
5378         .capset_set =                   selinux_capset_set,
5379         .sysctl =                       selinux_sysctl,
5380         .capable =                      selinux_capable,
5381         .quotactl =                     selinux_quotactl,
5382         .quota_on =                     selinux_quota_on,
5383         .syslog =                       selinux_syslog,
5384         .vm_enough_memory =             selinux_vm_enough_memory,
5385
5386         .netlink_send =                 selinux_netlink_send,
5387         .netlink_recv =                 selinux_netlink_recv,
5388
5389         .bprm_alloc_security =          selinux_bprm_alloc_security,
5390         .bprm_free_security =           selinux_bprm_free_security,
5391         .bprm_apply_creds =             selinux_bprm_apply_creds,
5392         .bprm_post_apply_creds =        selinux_bprm_post_apply_creds,
5393         .bprm_set_security =            selinux_bprm_set_security,
5394         .bprm_check_security =          selinux_bprm_check_security,
5395         .bprm_secureexec =              selinux_bprm_secureexec,
5396
5397         .sb_alloc_security =            selinux_sb_alloc_security,
5398         .sb_free_security =             selinux_sb_free_security,
5399         .sb_copy_data =                 selinux_sb_copy_data,
5400         .sb_kern_mount =                selinux_sb_kern_mount,
5401         .sb_show_options =              selinux_sb_show_options,
5402         .sb_statfs =                    selinux_sb_statfs,
5403         .sb_mount =                     selinux_mount,
5404         .sb_umount =                    selinux_umount,
5405         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5406         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5407         .sb_parse_opts_str =            selinux_parse_opts_str,
5408
5409
5410         .inode_alloc_security =         selinux_inode_alloc_security,
5411         .inode_free_security =          selinux_inode_free_security,
5412         .inode_init_security =          selinux_inode_init_security,
5413         .inode_create =                 selinux_inode_create,
5414         .inode_link =                   selinux_inode_link,
5415         .inode_unlink =                 selinux_inode_unlink,
5416         .inode_symlink =                selinux_inode_symlink,
5417         .inode_mkdir =                  selinux_inode_mkdir,
5418         .inode_rmdir =                  selinux_inode_rmdir,
5419         .inode_mknod =                  selinux_inode_mknod,
5420         .inode_rename =                 selinux_inode_rename,
5421         .inode_readlink =               selinux_inode_readlink,
5422         .inode_follow_link =            selinux_inode_follow_link,
5423         .inode_permission =             selinux_inode_permission,
5424         .inode_setattr =                selinux_inode_setattr,
5425         .inode_getattr =                selinux_inode_getattr,
5426         .inode_setxattr =               selinux_inode_setxattr,
5427         .inode_post_setxattr =          selinux_inode_post_setxattr,
5428         .inode_getxattr =               selinux_inode_getxattr,
5429         .inode_listxattr =              selinux_inode_listxattr,
5430         .inode_removexattr =            selinux_inode_removexattr,
5431         .inode_getsecurity =            selinux_inode_getsecurity,
5432         .inode_setsecurity =            selinux_inode_setsecurity,
5433         .inode_listsecurity =           selinux_inode_listsecurity,
5434         .inode_need_killpriv =          selinux_inode_need_killpriv,
5435         .inode_killpriv =               selinux_inode_killpriv,
5436         .inode_getsecid =               selinux_inode_getsecid,
5437
5438         .file_permission =              selinux_file_permission,
5439         .file_alloc_security =          selinux_file_alloc_security,
5440         .file_free_security =           selinux_file_free_security,
5441         .file_ioctl =                   selinux_file_ioctl,
5442         .file_mmap =                    selinux_file_mmap,
5443         .file_mprotect =                selinux_file_mprotect,
5444         .file_lock =                    selinux_file_lock,
5445         .file_fcntl =                   selinux_file_fcntl,
5446         .file_set_fowner =              selinux_file_set_fowner,
5447         .file_send_sigiotask =          selinux_file_send_sigiotask,
5448         .file_receive =                 selinux_file_receive,
5449
5450         .dentry_open =                  selinux_dentry_open,
5451
5452         .task_create =                  selinux_task_create,
5453         .task_alloc_security =          selinux_task_alloc_security,
5454         .task_free_security =           selinux_task_free_security,
5455         .task_setuid =                  selinux_task_setuid,
5456         .task_post_setuid =             selinux_task_post_setuid,
5457         .task_setgid =                  selinux_task_setgid,
5458         .task_setpgid =                 selinux_task_setpgid,
5459         .task_getpgid =                 selinux_task_getpgid,
5460         .task_getsid =                  selinux_task_getsid,
5461         .task_getsecid =                selinux_task_getsecid,
5462         .task_setgroups =               selinux_task_setgroups,
5463         .task_setnice =                 selinux_task_setnice,
5464         .task_setioprio =               selinux_task_setioprio,
5465         .task_getioprio =               selinux_task_getioprio,
5466         .task_setrlimit =               selinux_task_setrlimit,
5467         .task_setscheduler =            selinux_task_setscheduler,
5468         .task_getscheduler =            selinux_task_getscheduler,
5469         .task_movememory =              selinux_task_movememory,
5470         .task_kill =                    selinux_task_kill,
5471         .task_wait =                    selinux_task_wait,
5472         .task_prctl =                   selinux_task_prctl,
5473         .task_reparent_to_init =        selinux_task_reparent_to_init,
5474         .task_to_inode =                selinux_task_to_inode,
5475
5476         .ipc_permission =               selinux_ipc_permission,
5477         .ipc_getsecid =                 selinux_ipc_getsecid,
5478
5479         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5480         .msg_msg_free_security =        selinux_msg_msg_free_security,
5481
5482         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5483         .msg_queue_free_security =      selinux_msg_queue_free_security,
5484         .msg_queue_associate =          selinux_msg_queue_associate,
5485         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5486         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5487         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5488
5489         .shm_alloc_security =           selinux_shm_alloc_security,
5490         .shm_free_security =            selinux_shm_free_security,
5491         .shm_associate =                selinux_shm_associate,
5492         .shm_shmctl =                   selinux_shm_shmctl,
5493         .shm_shmat =                    selinux_shm_shmat,
5494
5495         .sem_alloc_security =           selinux_sem_alloc_security,
5496         .sem_free_security =            selinux_sem_free_security,
5497         .sem_associate =                selinux_sem_associate,
5498         .sem_semctl =                   selinux_sem_semctl,
5499         .sem_semop =                    selinux_sem_semop,
5500
5501         .d_instantiate =                selinux_d_instantiate,
5502
5503         .getprocattr =                  selinux_getprocattr,
5504         .setprocattr =                  selinux_setprocattr,
5505
5506         .secid_to_secctx =              selinux_secid_to_secctx,
5507         .secctx_to_secid =              selinux_secctx_to_secid,
5508         .release_secctx =               selinux_release_secctx,
5509
5510         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5511         .unix_may_send =                selinux_socket_unix_may_send,
5512
5513         .socket_create =                selinux_socket_create,
5514         .socket_post_create =           selinux_socket_post_create,
5515         .socket_bind =                  selinux_socket_bind,
5516         .socket_connect =               selinux_socket_connect,
5517         .socket_listen =                selinux_socket_listen,
5518         .socket_accept =                selinux_socket_accept,
5519         .socket_sendmsg =               selinux_socket_sendmsg,
5520         .socket_recvmsg =               selinux_socket_recvmsg,
5521         .socket_getsockname =           selinux_socket_getsockname,
5522         .socket_getpeername =           selinux_socket_getpeername,
5523         .socket_getsockopt =            selinux_socket_getsockopt,
5524         .socket_setsockopt =            selinux_socket_setsockopt,
5525         .socket_shutdown =              selinux_socket_shutdown,
5526         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5527         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5528         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5529         .sk_alloc_security =            selinux_sk_alloc_security,
5530         .sk_free_security =             selinux_sk_free_security,
5531         .sk_clone_security =            selinux_sk_clone_security,
5532         .sk_getsecid =                  selinux_sk_getsecid,
5533         .sock_graft =                   selinux_sock_graft,
5534         .inet_conn_request =            selinux_inet_conn_request,
5535         .inet_csk_clone =               selinux_inet_csk_clone,
5536         .inet_conn_established =        selinux_inet_conn_established,
5537         .req_classify_flow =            selinux_req_classify_flow,
5538
5539 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5540         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5541         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5542         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5543         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5544         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5545         .xfrm_state_free_security =     selinux_xfrm_state_free,
5546         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5547         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5548         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5549         .xfrm_decode_session =          selinux_xfrm_decode_session,
5550 #endif
5551
5552 #ifdef CONFIG_KEYS
5553         .key_alloc =                    selinux_key_alloc,
5554         .key_free =                     selinux_key_free,
5555         .key_permission =               selinux_key_permission,
5556         .key_getsecurity =              selinux_key_getsecurity,
5557 #endif
5558
5559 #ifdef CONFIG_AUDIT
5560         .audit_rule_init =              selinux_audit_rule_init,
5561         .audit_rule_known =             selinux_audit_rule_known,
5562         .audit_rule_match =             selinux_audit_rule_match,
5563         .audit_rule_free =              selinux_audit_rule_free,
5564 #endif
5565 };
5566
5567 static __init int selinux_init(void)
5568 {
5569         struct task_security_struct *tsec;
5570
5571         if (!security_module_enable(&selinux_ops)) {
5572                 selinux_enabled = 0;
5573                 return 0;
5574         }
5575
5576         if (!selinux_enabled) {
5577                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5578                 return 0;
5579         }
5580
5581         printk(KERN_INFO "SELinux:  Initializing.\n");
5582
5583         /* Set the security state for the initial task. */
5584         if (task_alloc_security(current))
5585                 panic("SELinux:  Failed to initialize initial task.\n");
5586         tsec = current->security;
5587         tsec->osid = tsec->sid = SECINITSID_KERNEL;
5588
5589         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5590                                             sizeof(struct inode_security_struct),
5591                                             0, SLAB_PANIC, NULL);
5592         avc_init();
5593
5594         secondary_ops = security_ops;
5595         if (!secondary_ops)
5596                 panic("SELinux: No initial security operations\n");
5597         if (register_security(&selinux_ops))
5598                 panic("SELinux: Unable to register with kernel.\n");
5599
5600         if (selinux_enforcing)
5601                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5602         else
5603                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5604
5605         return 0;
5606 }
5607
5608 void selinux_complete_init(void)
5609 {
5610         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5611
5612         /* Set up any superblocks initialized prior to the policy load. */
5613         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5614         spin_lock(&sb_lock);
5615         spin_lock(&sb_security_lock);
5616 next_sb:
5617         if (!list_empty(&superblock_security_head)) {
5618                 struct superblock_security_struct *sbsec =
5619                                 list_entry(superblock_security_head.next,
5620                                            struct superblock_security_struct,
5621                                            list);
5622                 struct super_block *sb = sbsec->sb;
5623                 sb->s_count++;
5624                 spin_unlock(&sb_security_lock);
5625                 spin_unlock(&sb_lock);
5626                 down_read(&sb->s_umount);
5627                 if (sb->s_root)
5628                         superblock_doinit(sb, NULL);
5629                 drop_super(sb);
5630                 spin_lock(&sb_lock);
5631                 spin_lock(&sb_security_lock);
5632                 list_del_init(&sbsec->list);
5633                 goto next_sb;
5634         }
5635         spin_unlock(&sb_security_lock);
5636         spin_unlock(&sb_lock);
5637 }
5638
5639 /* SELinux requires early initialization in order to label
5640    all processes and objects when they are created. */
5641 security_initcall(selinux_init);
5642
5643 #if defined(CONFIG_NETFILTER)
5644
5645 static struct nf_hook_ops selinux_ipv4_ops[] = {
5646         {
5647                 .hook =         selinux_ipv4_postroute,
5648                 .owner =        THIS_MODULE,
5649                 .pf =           PF_INET,
5650                 .hooknum =      NF_INET_POST_ROUTING,
5651                 .priority =     NF_IP_PRI_SELINUX_LAST,
5652         },
5653         {
5654                 .hook =         selinux_ipv4_forward,
5655                 .owner =        THIS_MODULE,
5656                 .pf =           PF_INET,
5657                 .hooknum =      NF_INET_FORWARD,
5658                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5659         }
5660 };
5661
5662 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5663
5664 static struct nf_hook_ops selinux_ipv6_ops[] = {
5665         {
5666                 .hook =         selinux_ipv6_postroute,
5667                 .owner =        THIS_MODULE,
5668                 .pf =           PF_INET6,
5669                 .hooknum =      NF_INET_POST_ROUTING,
5670                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5671         },
5672         {
5673                 .hook =         selinux_ipv6_forward,
5674                 .owner =        THIS_MODULE,
5675                 .pf =           PF_INET6,
5676                 .hooknum =      NF_INET_FORWARD,
5677                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5678         }
5679 };
5680
5681 #endif  /* IPV6 */
5682
5683 static int __init selinux_nf_ip_init(void)
5684 {
5685         int err = 0;
5686
5687         if (!selinux_enabled)
5688                 goto out;
5689
5690         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5691
5692         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5693         if (err)
5694                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5695
5696 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5697         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5698         if (err)
5699                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5700 #endif  /* IPV6 */
5701
5702 out:
5703         return err;
5704 }
5705
5706 __initcall(selinux_nf_ip_init);
5707
5708 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5709 static void selinux_nf_ip_exit(void)
5710 {
5711         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5712
5713         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5714 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5715         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5716 #endif  /* IPV6 */
5717 }
5718 #endif
5719
5720 #else /* CONFIG_NETFILTER */
5721
5722 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5723 #define selinux_nf_ip_exit()
5724 #endif
5725
5726 #endif /* CONFIG_NETFILTER */
5727
5728 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5729 static int selinux_disabled;
5730
5731 int selinux_disable(void)
5732 {
5733         extern void exit_sel_fs(void);
5734
5735         if (ss_initialized) {
5736                 /* Not permitted after initial policy load. */
5737                 return -EINVAL;
5738         }
5739
5740         if (selinux_disabled) {
5741                 /* Only do this once. */
5742                 return -EINVAL;
5743         }
5744
5745         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5746
5747         selinux_disabled = 1;
5748         selinux_enabled = 0;
5749
5750         /* Reset security_ops to the secondary module, dummy or capability. */
5751         security_ops = secondary_ops;
5752
5753         /* Unregister netfilter hooks. */
5754         selinux_nf_ip_exit();
5755
5756         /* Unregister selinuxfs. */
5757         exit_sel_fs();
5758
5759         return 0;
5760 }
5761 #endif