selinux: Fix missing calls to netlbl_skbuff_err()
[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 void selinux_write_opts(struct seq_file *m, struct security_mnt_opts *opts)
961 {
962         int i;
963         char *prefix;
964
965         for (i = 0; i < opts->num_mnt_opts; i++) {
966                 char *has_comma = strchr(opts->mnt_opts[i], ',');
967
968                 switch (opts->mnt_opts_flags[i]) {
969                 case CONTEXT_MNT:
970                         prefix = CONTEXT_STR;
971                         break;
972                 case FSCONTEXT_MNT:
973                         prefix = FSCONTEXT_STR;
974                         break;
975                 case ROOTCONTEXT_MNT:
976                         prefix = ROOTCONTEXT_STR;
977                         break;
978                 case DEFCONTEXT_MNT:
979                         prefix = DEFCONTEXT_STR;
980                         break;
981                 default:
982                         BUG();
983                 };
984                 /* we need a comma before each option */
985                 seq_putc(m, ',');
986                 seq_puts(m, prefix);
987                 if (has_comma)
988                         seq_putc(m, '\"');
989                 seq_puts(m, opts->mnt_opts[i]);
990                 if (has_comma)
991                         seq_putc(m, '\"');
992         }
993 }
994
995 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
996 {
997         struct security_mnt_opts opts;
998         int rc;
999
1000         rc = selinux_get_mnt_opts(sb, &opts);
1001         if (rc) {
1002                 /* before policy load we may get EINVAL, don't show anything */
1003                 if (rc == -EINVAL)
1004                         rc = 0;
1005                 return rc;
1006         }
1007
1008         selinux_write_opts(m, &opts);
1009
1010         security_free_mnt_opts(&opts);
1011
1012         return rc;
1013 }
1014
1015 static inline u16 inode_mode_to_security_class(umode_t mode)
1016 {
1017         switch (mode & S_IFMT) {
1018         case S_IFSOCK:
1019                 return SECCLASS_SOCK_FILE;
1020         case S_IFLNK:
1021                 return SECCLASS_LNK_FILE;
1022         case S_IFREG:
1023                 return SECCLASS_FILE;
1024         case S_IFBLK:
1025                 return SECCLASS_BLK_FILE;
1026         case S_IFDIR:
1027                 return SECCLASS_DIR;
1028         case S_IFCHR:
1029                 return SECCLASS_CHR_FILE;
1030         case S_IFIFO:
1031                 return SECCLASS_FIFO_FILE;
1032
1033         }
1034
1035         return SECCLASS_FILE;
1036 }
1037
1038 static inline int default_protocol_stream(int protocol)
1039 {
1040         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1041 }
1042
1043 static inline int default_protocol_dgram(int protocol)
1044 {
1045         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1046 }
1047
1048 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1049 {
1050         switch (family) {
1051         case PF_UNIX:
1052                 switch (type) {
1053                 case SOCK_STREAM:
1054                 case SOCK_SEQPACKET:
1055                         return SECCLASS_UNIX_STREAM_SOCKET;
1056                 case SOCK_DGRAM:
1057                         return SECCLASS_UNIX_DGRAM_SOCKET;
1058                 }
1059                 break;
1060         case PF_INET:
1061         case PF_INET6:
1062                 switch (type) {
1063                 case SOCK_STREAM:
1064                         if (default_protocol_stream(protocol))
1065                                 return SECCLASS_TCP_SOCKET;
1066                         else
1067                                 return SECCLASS_RAWIP_SOCKET;
1068                 case SOCK_DGRAM:
1069                         if (default_protocol_dgram(protocol))
1070                                 return SECCLASS_UDP_SOCKET;
1071                         else
1072                                 return SECCLASS_RAWIP_SOCKET;
1073                 case SOCK_DCCP:
1074                         return SECCLASS_DCCP_SOCKET;
1075                 default:
1076                         return SECCLASS_RAWIP_SOCKET;
1077                 }
1078                 break;
1079         case PF_NETLINK:
1080                 switch (protocol) {
1081                 case NETLINK_ROUTE:
1082                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1083                 case NETLINK_FIREWALL:
1084                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1085                 case NETLINK_INET_DIAG:
1086                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1087                 case NETLINK_NFLOG:
1088                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1089                 case NETLINK_XFRM:
1090                         return SECCLASS_NETLINK_XFRM_SOCKET;
1091                 case NETLINK_SELINUX:
1092                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1093                 case NETLINK_AUDIT:
1094                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1095                 case NETLINK_IP6_FW:
1096                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1097                 case NETLINK_DNRTMSG:
1098                         return SECCLASS_NETLINK_DNRT_SOCKET;
1099                 case NETLINK_KOBJECT_UEVENT:
1100                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1101                 default:
1102                         return SECCLASS_NETLINK_SOCKET;
1103                 }
1104         case PF_PACKET:
1105                 return SECCLASS_PACKET_SOCKET;
1106         case PF_KEY:
1107                 return SECCLASS_KEY_SOCKET;
1108         case PF_APPLETALK:
1109                 return SECCLASS_APPLETALK_SOCKET;
1110         }
1111
1112         return SECCLASS_SOCKET;
1113 }
1114
1115 #ifdef CONFIG_PROC_FS
1116 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1117                                 u16 tclass,
1118                                 u32 *sid)
1119 {
1120         int buflen, rc;
1121         char *buffer, *path, *end;
1122
1123         buffer = (char *)__get_free_page(GFP_KERNEL);
1124         if (!buffer)
1125                 return -ENOMEM;
1126
1127         buflen = PAGE_SIZE;
1128         end = buffer+buflen;
1129         *--end = '\0';
1130         buflen--;
1131         path = end-1;
1132         *path = '/';
1133         while (de && de != de->parent) {
1134                 buflen -= de->namelen + 1;
1135                 if (buflen < 0)
1136                         break;
1137                 end -= de->namelen;
1138                 memcpy(end, de->name, de->namelen);
1139                 *--end = '/';
1140                 path = end;
1141                 de = de->parent;
1142         }
1143         rc = security_genfs_sid("proc", path, tclass, sid);
1144         free_page((unsigned long)buffer);
1145         return rc;
1146 }
1147 #else
1148 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1149                                 u16 tclass,
1150                                 u32 *sid)
1151 {
1152         return -EINVAL;
1153 }
1154 #endif
1155
1156 /* The inode's security attributes must be initialized before first use. */
1157 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1158 {
1159         struct superblock_security_struct *sbsec = NULL;
1160         struct inode_security_struct *isec = inode->i_security;
1161         u32 sid;
1162         struct dentry *dentry;
1163 #define INITCONTEXTLEN 255
1164         char *context = NULL;
1165         unsigned len = 0;
1166         int rc = 0;
1167
1168         if (isec->initialized)
1169                 goto out;
1170
1171         mutex_lock(&isec->lock);
1172         if (isec->initialized)
1173                 goto out_unlock;
1174
1175         sbsec = inode->i_sb->s_security;
1176         if (!sbsec->initialized) {
1177                 /* Defer initialization until selinux_complete_init,
1178                    after the initial policy is loaded and the security
1179                    server is ready to handle calls. */
1180                 spin_lock(&sbsec->isec_lock);
1181                 if (list_empty(&isec->list))
1182                         list_add(&isec->list, &sbsec->isec_head);
1183                 spin_unlock(&sbsec->isec_lock);
1184                 goto out_unlock;
1185         }
1186
1187         switch (sbsec->behavior) {
1188         case SECURITY_FS_USE_XATTR:
1189                 if (!inode->i_op->getxattr) {
1190                         isec->sid = sbsec->def_sid;
1191                         break;
1192                 }
1193
1194                 /* Need a dentry, since the xattr API requires one.
1195                    Life would be simpler if we could just pass the inode. */
1196                 if (opt_dentry) {
1197                         /* Called from d_instantiate or d_splice_alias. */
1198                         dentry = dget(opt_dentry);
1199                 } else {
1200                         /* Called from selinux_complete_init, try to find a dentry. */
1201                         dentry = d_find_alias(inode);
1202                 }
1203                 if (!dentry) {
1204                         printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1205                                "ino=%ld\n", __func__, inode->i_sb->s_id,
1206                                inode->i_ino);
1207                         goto out_unlock;
1208                 }
1209
1210                 len = INITCONTEXTLEN;
1211                 context = kmalloc(len, GFP_NOFS);
1212                 if (!context) {
1213                         rc = -ENOMEM;
1214                         dput(dentry);
1215                         goto out_unlock;
1216                 }
1217                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1218                                            context, len);
1219                 if (rc == -ERANGE) {
1220                         /* Need a larger buffer.  Query for the right size. */
1221                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1222                                                    NULL, 0);
1223                         if (rc < 0) {
1224                                 dput(dentry);
1225                                 goto out_unlock;
1226                         }
1227                         kfree(context);
1228                         len = rc;
1229                         context = kmalloc(len, GFP_NOFS);
1230                         if (!context) {
1231                                 rc = -ENOMEM;
1232                                 dput(dentry);
1233                                 goto out_unlock;
1234                         }
1235                         rc = inode->i_op->getxattr(dentry,
1236                                                    XATTR_NAME_SELINUX,
1237                                                    context, len);
1238                 }
1239                 dput(dentry);
1240                 if (rc < 0) {
1241                         if (rc != -ENODATA) {
1242                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1243                                        "%d for dev=%s ino=%ld\n", __func__,
1244                                        -rc, inode->i_sb->s_id, inode->i_ino);
1245                                 kfree(context);
1246                                 goto out_unlock;
1247                         }
1248                         /* Map ENODATA to the default file SID */
1249                         sid = sbsec->def_sid;
1250                         rc = 0;
1251                 } else {
1252                         rc = security_context_to_sid_default(context, rc, &sid,
1253                                                              sbsec->def_sid,
1254                                                              GFP_NOFS);
1255                         if (rc) {
1256                                 printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1257                                        "returned %d for dev=%s ino=%ld\n",
1258                                        __func__, context, -rc,
1259                                        inode->i_sb->s_id, inode->i_ino);
1260                                 kfree(context);
1261                                 /* Leave with the unlabeled SID */
1262                                 rc = 0;
1263                                 break;
1264                         }
1265                 }
1266                 kfree(context);
1267                 isec->sid = sid;
1268                 break;
1269         case SECURITY_FS_USE_TASK:
1270                 isec->sid = isec->task_sid;
1271                 break;
1272         case SECURITY_FS_USE_TRANS:
1273                 /* Default to the fs SID. */
1274                 isec->sid = sbsec->sid;
1275
1276                 /* Try to obtain a transition SID. */
1277                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1278                 rc = security_transition_sid(isec->task_sid,
1279                                              sbsec->sid,
1280                                              isec->sclass,
1281                                              &sid);
1282                 if (rc)
1283                         goto out_unlock;
1284                 isec->sid = sid;
1285                 break;
1286         case SECURITY_FS_USE_MNTPOINT:
1287                 isec->sid = sbsec->mntpoint_sid;
1288                 break;
1289         default:
1290                 /* Default to the fs superblock SID. */
1291                 isec->sid = sbsec->sid;
1292
1293                 if (sbsec->proc) {
1294                         struct proc_inode *proci = PROC_I(inode);
1295                         if (proci->pde) {
1296                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1297                                 rc = selinux_proc_get_sid(proci->pde,
1298                                                           isec->sclass,
1299                                                           &sid);
1300                                 if (rc)
1301                                         goto out_unlock;
1302                                 isec->sid = sid;
1303                         }
1304                 }
1305                 break;
1306         }
1307
1308         isec->initialized = 1;
1309
1310 out_unlock:
1311         mutex_unlock(&isec->lock);
1312 out:
1313         if (isec->sclass == SECCLASS_FILE)
1314                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1315         return rc;
1316 }
1317
1318 /* Convert a Linux signal to an access vector. */
1319 static inline u32 signal_to_av(int sig)
1320 {
1321         u32 perm = 0;
1322
1323         switch (sig) {
1324         case SIGCHLD:
1325                 /* Commonly granted from child to parent. */
1326                 perm = PROCESS__SIGCHLD;
1327                 break;
1328         case SIGKILL:
1329                 /* Cannot be caught or ignored */
1330                 perm = PROCESS__SIGKILL;
1331                 break;
1332         case SIGSTOP:
1333                 /* Cannot be caught or ignored */
1334                 perm = PROCESS__SIGSTOP;
1335                 break;
1336         default:
1337                 /* All other signals. */
1338                 perm = PROCESS__SIGNAL;
1339                 break;
1340         }
1341
1342         return perm;
1343 }
1344
1345 /* Check permission betweeen a pair of tasks, e.g. signal checks,
1346    fork check, ptrace check, etc. */
1347 static int task_has_perm(struct task_struct *tsk1,
1348                          struct task_struct *tsk2,
1349                          u32 perms)
1350 {
1351         struct task_security_struct *tsec1, *tsec2;
1352
1353         tsec1 = tsk1->security;
1354         tsec2 = tsk2->security;
1355         return avc_has_perm(tsec1->sid, tsec2->sid,
1356                             SECCLASS_PROCESS, perms, NULL);
1357 }
1358
1359 #if CAP_LAST_CAP > 63
1360 #error Fix SELinux to handle capabilities > 63.
1361 #endif
1362
1363 /* Check whether a task is allowed to use a capability. */
1364 static int task_has_capability(struct task_struct *tsk,
1365                                int cap)
1366 {
1367         struct task_security_struct *tsec;
1368         struct avc_audit_data ad;
1369         u16 sclass;
1370         u32 av = CAP_TO_MASK(cap);
1371
1372         tsec = tsk->security;
1373
1374         AVC_AUDIT_DATA_INIT(&ad, CAP);
1375         ad.tsk = tsk;
1376         ad.u.cap = cap;
1377
1378         switch (CAP_TO_INDEX(cap)) {
1379         case 0:
1380                 sclass = SECCLASS_CAPABILITY;
1381                 break;
1382         case 1:
1383                 sclass = SECCLASS_CAPABILITY2;
1384                 break;
1385         default:
1386                 printk(KERN_ERR
1387                        "SELinux:  out of range capability %d\n", cap);
1388                 BUG();
1389         }
1390         return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad);
1391 }
1392
1393 /* Check whether a task is allowed to use a system operation. */
1394 static int task_has_system(struct task_struct *tsk,
1395                            u32 perms)
1396 {
1397         struct task_security_struct *tsec;
1398
1399         tsec = tsk->security;
1400
1401         return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1402                             SECCLASS_SYSTEM, perms, NULL);
1403 }
1404
1405 /* Check whether a task has a particular permission to an inode.
1406    The 'adp' parameter is optional and allows other audit
1407    data to be passed (e.g. the dentry). */
1408 static int inode_has_perm(struct task_struct *tsk,
1409                           struct inode *inode,
1410                           u32 perms,
1411                           struct avc_audit_data *adp)
1412 {
1413         struct task_security_struct *tsec;
1414         struct inode_security_struct *isec;
1415         struct avc_audit_data ad;
1416
1417         if (unlikely(IS_PRIVATE(inode)))
1418                 return 0;
1419
1420         tsec = tsk->security;
1421         isec = inode->i_security;
1422
1423         if (!adp) {
1424                 adp = &ad;
1425                 AVC_AUDIT_DATA_INIT(&ad, FS);
1426                 ad.u.fs.inode = inode;
1427         }
1428
1429         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1430 }
1431
1432 /* Same as inode_has_perm, but pass explicit audit data containing
1433    the dentry to help the auditing code to more easily generate the
1434    pathname if needed. */
1435 static inline int dentry_has_perm(struct task_struct *tsk,
1436                                   struct vfsmount *mnt,
1437                                   struct dentry *dentry,
1438                                   u32 av)
1439 {
1440         struct inode *inode = dentry->d_inode;
1441         struct avc_audit_data ad;
1442         AVC_AUDIT_DATA_INIT(&ad, FS);
1443         ad.u.fs.path.mnt = mnt;
1444         ad.u.fs.path.dentry = dentry;
1445         return inode_has_perm(tsk, inode, av, &ad);
1446 }
1447
1448 /* Check whether a task can use an open file descriptor to
1449    access an inode in a given way.  Check access to the
1450    descriptor itself, and then use dentry_has_perm to
1451    check a particular permission to the file.
1452    Access to the descriptor is implicitly granted if it
1453    has the same SID as the process.  If av is zero, then
1454    access to the file is not checked, e.g. for cases
1455    where only the descriptor is affected like seek. */
1456 static int file_has_perm(struct task_struct *tsk,
1457                                 struct file *file,
1458                                 u32 av)
1459 {
1460         struct task_security_struct *tsec = tsk->security;
1461         struct file_security_struct *fsec = file->f_security;
1462         struct inode *inode = file->f_path.dentry->d_inode;
1463         struct avc_audit_data ad;
1464         int rc;
1465
1466         AVC_AUDIT_DATA_INIT(&ad, FS);
1467         ad.u.fs.path = file->f_path;
1468
1469         if (tsec->sid != fsec->sid) {
1470                 rc = avc_has_perm(tsec->sid, fsec->sid,
1471                                   SECCLASS_FD,
1472                                   FD__USE,
1473                                   &ad);
1474                 if (rc)
1475                         return rc;
1476         }
1477
1478         /* av is zero if only checking access to the descriptor. */
1479         if (av)
1480                 return inode_has_perm(tsk, inode, av, &ad);
1481
1482         return 0;
1483 }
1484
1485 /* Check whether a task can create a file. */
1486 static int may_create(struct inode *dir,
1487                       struct dentry *dentry,
1488                       u16 tclass)
1489 {
1490         struct task_security_struct *tsec;
1491         struct inode_security_struct *dsec;
1492         struct superblock_security_struct *sbsec;
1493         u32 newsid;
1494         struct avc_audit_data ad;
1495         int rc;
1496
1497         tsec = current->security;
1498         dsec = dir->i_security;
1499         sbsec = dir->i_sb->s_security;
1500
1501         AVC_AUDIT_DATA_INIT(&ad, FS);
1502         ad.u.fs.path.dentry = dentry;
1503
1504         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1505                           DIR__ADD_NAME | DIR__SEARCH,
1506                           &ad);
1507         if (rc)
1508                 return rc;
1509
1510         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1511                 newsid = tsec->create_sid;
1512         } else {
1513                 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1514                                              &newsid);
1515                 if (rc)
1516                         return rc;
1517         }
1518
1519         rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1520         if (rc)
1521                 return rc;
1522
1523         return avc_has_perm(newsid, sbsec->sid,
1524                             SECCLASS_FILESYSTEM,
1525                             FILESYSTEM__ASSOCIATE, &ad);
1526 }
1527
1528 /* Check whether a task can create a key. */
1529 static int may_create_key(u32 ksid,
1530                           struct task_struct *ctx)
1531 {
1532         struct task_security_struct *tsec;
1533
1534         tsec = ctx->security;
1535
1536         return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1537 }
1538
1539 #define MAY_LINK        0
1540 #define MAY_UNLINK      1
1541 #define MAY_RMDIR       2
1542
1543 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1544 static int may_link(struct inode *dir,
1545                     struct dentry *dentry,
1546                     int kind)
1547
1548 {
1549         struct task_security_struct *tsec;
1550         struct inode_security_struct *dsec, *isec;
1551         struct avc_audit_data ad;
1552         u32 av;
1553         int rc;
1554
1555         tsec = current->security;
1556         dsec = dir->i_security;
1557         isec = dentry->d_inode->i_security;
1558
1559         AVC_AUDIT_DATA_INIT(&ad, FS);
1560         ad.u.fs.path.dentry = dentry;
1561
1562         av = DIR__SEARCH;
1563         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1564         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1565         if (rc)
1566                 return rc;
1567
1568         switch (kind) {
1569         case MAY_LINK:
1570                 av = FILE__LINK;
1571                 break;
1572         case MAY_UNLINK:
1573                 av = FILE__UNLINK;
1574                 break;
1575         case MAY_RMDIR:
1576                 av = DIR__RMDIR;
1577                 break;
1578         default:
1579                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1580                         __func__, kind);
1581                 return 0;
1582         }
1583
1584         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1585         return rc;
1586 }
1587
1588 static inline int may_rename(struct inode *old_dir,
1589                              struct dentry *old_dentry,
1590                              struct inode *new_dir,
1591                              struct dentry *new_dentry)
1592 {
1593         struct task_security_struct *tsec;
1594         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1595         struct avc_audit_data ad;
1596         u32 av;
1597         int old_is_dir, new_is_dir;
1598         int rc;
1599
1600         tsec = current->security;
1601         old_dsec = old_dir->i_security;
1602         old_isec = old_dentry->d_inode->i_security;
1603         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1604         new_dsec = new_dir->i_security;
1605
1606         AVC_AUDIT_DATA_INIT(&ad, FS);
1607
1608         ad.u.fs.path.dentry = old_dentry;
1609         rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1610                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1611         if (rc)
1612                 return rc;
1613         rc = avc_has_perm(tsec->sid, old_isec->sid,
1614                           old_isec->sclass, FILE__RENAME, &ad);
1615         if (rc)
1616                 return rc;
1617         if (old_is_dir && new_dir != old_dir) {
1618                 rc = avc_has_perm(tsec->sid, old_isec->sid,
1619                                   old_isec->sclass, DIR__REPARENT, &ad);
1620                 if (rc)
1621                         return rc;
1622         }
1623
1624         ad.u.fs.path.dentry = new_dentry;
1625         av = DIR__ADD_NAME | DIR__SEARCH;
1626         if (new_dentry->d_inode)
1627                 av |= DIR__REMOVE_NAME;
1628         rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1629         if (rc)
1630                 return rc;
1631         if (new_dentry->d_inode) {
1632                 new_isec = new_dentry->d_inode->i_security;
1633                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1634                 rc = avc_has_perm(tsec->sid, new_isec->sid,
1635                                   new_isec->sclass,
1636                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1637                 if (rc)
1638                         return rc;
1639         }
1640
1641         return 0;
1642 }
1643
1644 /* Check whether a task can perform a filesystem operation. */
1645 static int superblock_has_perm(struct task_struct *tsk,
1646                                struct super_block *sb,
1647                                u32 perms,
1648                                struct avc_audit_data *ad)
1649 {
1650         struct task_security_struct *tsec;
1651         struct superblock_security_struct *sbsec;
1652
1653         tsec = tsk->security;
1654         sbsec = sb->s_security;
1655         return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1656                             perms, ad);
1657 }
1658
1659 /* Convert a Linux mode and permission mask to an access vector. */
1660 static inline u32 file_mask_to_av(int mode, int mask)
1661 {
1662         u32 av = 0;
1663
1664         if ((mode & S_IFMT) != S_IFDIR) {
1665                 if (mask & MAY_EXEC)
1666                         av |= FILE__EXECUTE;
1667                 if (mask & MAY_READ)
1668                         av |= FILE__READ;
1669
1670                 if (mask & MAY_APPEND)
1671                         av |= FILE__APPEND;
1672                 else if (mask & MAY_WRITE)
1673                         av |= FILE__WRITE;
1674
1675         } else {
1676                 if (mask & MAY_EXEC)
1677                         av |= DIR__SEARCH;
1678                 if (mask & MAY_WRITE)
1679                         av |= DIR__WRITE;
1680                 if (mask & MAY_READ)
1681                         av |= DIR__READ;
1682         }
1683
1684         return av;
1685 }
1686
1687 /*
1688  * Convert a file mask to an access vector and include the correct open
1689  * open permission.
1690  */
1691 static inline u32 open_file_mask_to_av(int mode, int mask)
1692 {
1693         u32 av = file_mask_to_av(mode, mask);
1694
1695         if (selinux_policycap_openperm) {
1696                 /*
1697                  * lnk files and socks do not really have an 'open'
1698                  */
1699                 if (S_ISREG(mode))
1700                         av |= FILE__OPEN;
1701                 else if (S_ISCHR(mode))
1702                         av |= CHR_FILE__OPEN;
1703                 else if (S_ISBLK(mode))
1704                         av |= BLK_FILE__OPEN;
1705                 else if (S_ISFIFO(mode))
1706                         av |= FIFO_FILE__OPEN;
1707                 else if (S_ISDIR(mode))
1708                         av |= DIR__OPEN;
1709                 else
1710                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1711                                 "unknown mode:%x\n", __func__, mode);
1712         }
1713         return av;
1714 }
1715
1716 /* Convert a Linux file to an access vector. */
1717 static inline u32 file_to_av(struct file *file)
1718 {
1719         u32 av = 0;
1720
1721         if (file->f_mode & FMODE_READ)
1722                 av |= FILE__READ;
1723         if (file->f_mode & FMODE_WRITE) {
1724                 if (file->f_flags & O_APPEND)
1725                         av |= FILE__APPEND;
1726                 else
1727                         av |= FILE__WRITE;
1728         }
1729         if (!av) {
1730                 /*
1731                  * Special file opened with flags 3 for ioctl-only use.
1732                  */
1733                 av = FILE__IOCTL;
1734         }
1735
1736         return av;
1737 }
1738
1739 /* Hook functions begin here. */
1740
1741 static int selinux_ptrace_may_access(struct task_struct *child,
1742                                      unsigned int mode)
1743 {
1744         int rc;
1745
1746         rc = secondary_ops->ptrace_may_access(child, mode);
1747         if (rc)
1748                 return rc;
1749
1750         if (mode == PTRACE_MODE_READ) {
1751                 struct task_security_struct *tsec = current->security;
1752                 struct task_security_struct *csec = child->security;
1753                 return avc_has_perm(tsec->sid, csec->sid,
1754                                     SECCLASS_FILE, FILE__READ, NULL);
1755         }
1756
1757         return task_has_perm(current, child, PROCESS__PTRACE);
1758 }
1759
1760 static int selinux_ptrace_traceme(struct task_struct *parent)
1761 {
1762         int rc;
1763
1764         rc = secondary_ops->ptrace_traceme(parent);
1765         if (rc)
1766                 return rc;
1767
1768         return task_has_perm(parent, current, PROCESS__PTRACE);
1769 }
1770
1771 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1772                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1773 {
1774         int error;
1775
1776         error = task_has_perm(current, target, PROCESS__GETCAP);
1777         if (error)
1778                 return error;
1779
1780         return secondary_ops->capget(target, effective, inheritable, permitted);
1781 }
1782
1783 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1784                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1785 {
1786         int error;
1787
1788         error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1789         if (error)
1790                 return error;
1791
1792         return task_has_perm(current, target, PROCESS__SETCAP);
1793 }
1794
1795 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1796                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1797 {
1798         secondary_ops->capset_set(target, effective, inheritable, permitted);
1799 }
1800
1801 static int selinux_capable(struct task_struct *tsk, int cap)
1802 {
1803         int rc;
1804
1805         rc = secondary_ops->capable(tsk, cap);
1806         if (rc)
1807                 return rc;
1808
1809         return task_has_capability(tsk, cap);
1810 }
1811
1812 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1813 {
1814         int buflen, rc;
1815         char *buffer, *path, *end;
1816
1817         rc = -ENOMEM;
1818         buffer = (char *)__get_free_page(GFP_KERNEL);
1819         if (!buffer)
1820                 goto out;
1821
1822         buflen = PAGE_SIZE;
1823         end = buffer+buflen;
1824         *--end = '\0';
1825         buflen--;
1826         path = end-1;
1827         *path = '/';
1828         while (table) {
1829                 const char *name = table->procname;
1830                 size_t namelen = strlen(name);
1831                 buflen -= namelen + 1;
1832                 if (buflen < 0)
1833                         goto out_free;
1834                 end -= namelen;
1835                 memcpy(end, name, namelen);
1836                 *--end = '/';
1837                 path = end;
1838                 table = table->parent;
1839         }
1840         buflen -= 4;
1841         if (buflen < 0)
1842                 goto out_free;
1843         end -= 4;
1844         memcpy(end, "/sys", 4);
1845         path = end;
1846         rc = security_genfs_sid("proc", path, tclass, sid);
1847 out_free:
1848         free_page((unsigned long)buffer);
1849 out:
1850         return rc;
1851 }
1852
1853 static int selinux_sysctl(ctl_table *table, int op)
1854 {
1855         int error = 0;
1856         u32 av;
1857         struct task_security_struct *tsec;
1858         u32 tsid;
1859         int rc;
1860
1861         rc = secondary_ops->sysctl(table, op);
1862         if (rc)
1863                 return rc;
1864
1865         tsec = current->security;
1866
1867         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1868                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1869         if (rc) {
1870                 /* Default to the well-defined sysctl SID. */
1871                 tsid = SECINITSID_SYSCTL;
1872         }
1873
1874         /* The op values are "defined" in sysctl.c, thereby creating
1875          * a bad coupling between this module and sysctl.c */
1876         if (op == 001) {
1877                 error = avc_has_perm(tsec->sid, tsid,
1878                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1879         } else {
1880                 av = 0;
1881                 if (op & 004)
1882                         av |= FILE__READ;
1883                 if (op & 002)
1884                         av |= FILE__WRITE;
1885                 if (av)
1886                         error = avc_has_perm(tsec->sid, tsid,
1887                                              SECCLASS_FILE, av, NULL);
1888         }
1889
1890         return error;
1891 }
1892
1893 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1894 {
1895         int rc = 0;
1896
1897         if (!sb)
1898                 return 0;
1899
1900         switch (cmds) {
1901         case Q_SYNC:
1902         case Q_QUOTAON:
1903         case Q_QUOTAOFF:
1904         case Q_SETINFO:
1905         case Q_SETQUOTA:
1906                 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD,
1907                                          NULL);
1908                 break;
1909         case Q_GETFMT:
1910         case Q_GETINFO:
1911         case Q_GETQUOTA:
1912                 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET,
1913                                          NULL);
1914                 break;
1915         default:
1916                 rc = 0;  /* let the kernel handle invalid cmds */
1917                 break;
1918         }
1919         return rc;
1920 }
1921
1922 static int selinux_quota_on(struct dentry *dentry)
1923 {
1924         return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1925 }
1926
1927 static int selinux_syslog(int type)
1928 {
1929         int rc;
1930
1931         rc = secondary_ops->syslog(type);
1932         if (rc)
1933                 return rc;
1934
1935         switch (type) {
1936         case 3:         /* Read last kernel messages */
1937         case 10:        /* Return size of the log buffer */
1938                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1939                 break;
1940         case 6:         /* Disable logging to console */
1941         case 7:         /* Enable logging to console */
1942         case 8:         /* Set level of messages printed to console */
1943                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1944                 break;
1945         case 0:         /* Close log */
1946         case 1:         /* Open log */
1947         case 2:         /* Read from log */
1948         case 4:         /* Read/clear last kernel messages */
1949         case 5:         /* Clear ring buffer */
1950         default:
1951                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1952                 break;
1953         }
1954         return rc;
1955 }
1956
1957 /*
1958  * Check that a process has enough memory to allocate a new virtual
1959  * mapping. 0 means there is enough memory for the allocation to
1960  * succeed and -ENOMEM implies there is not.
1961  *
1962  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1963  * if the capability is granted, but __vm_enough_memory requires 1 if
1964  * the capability is granted.
1965  *
1966  * Do not audit the selinux permission check, as this is applied to all
1967  * processes that allocate mappings.
1968  */
1969 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1970 {
1971         int rc, cap_sys_admin = 0;
1972         struct task_security_struct *tsec = current->security;
1973
1974         rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1975         if (rc == 0)
1976                 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1977                                           SECCLASS_CAPABILITY,
1978                                           CAP_TO_MASK(CAP_SYS_ADMIN),
1979                                           0,
1980                                           NULL);
1981
1982         if (rc == 0)
1983                 cap_sys_admin = 1;
1984
1985         return __vm_enough_memory(mm, pages, cap_sys_admin);
1986 }
1987
1988 /* binprm security operations */
1989
1990 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1991 {
1992         struct bprm_security_struct *bsec;
1993
1994         bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1995         if (!bsec)
1996                 return -ENOMEM;
1997
1998         bsec->sid = SECINITSID_UNLABELED;
1999         bsec->set = 0;
2000
2001         bprm->security = bsec;
2002         return 0;
2003 }
2004
2005 static int selinux_bprm_set_security(struct linux_binprm *bprm)
2006 {
2007         struct task_security_struct *tsec;
2008         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2009         struct inode_security_struct *isec;
2010         struct bprm_security_struct *bsec;
2011         u32 newsid;
2012         struct avc_audit_data ad;
2013         int rc;
2014
2015         rc = secondary_ops->bprm_set_security(bprm);
2016         if (rc)
2017                 return rc;
2018
2019         bsec = bprm->security;
2020
2021         if (bsec->set)
2022                 return 0;
2023
2024         tsec = current->security;
2025         isec = inode->i_security;
2026
2027         /* Default to the current task SID. */
2028         bsec->sid = tsec->sid;
2029
2030         /* Reset fs, key, and sock SIDs on execve. */
2031         tsec->create_sid = 0;
2032         tsec->keycreate_sid = 0;
2033         tsec->sockcreate_sid = 0;
2034
2035         if (tsec->exec_sid) {
2036                 newsid = tsec->exec_sid;
2037                 /* Reset exec SID on execve. */
2038                 tsec->exec_sid = 0;
2039         } else {
2040                 /* Check for a default transition on this program. */
2041                 rc = security_transition_sid(tsec->sid, isec->sid,
2042                                              SECCLASS_PROCESS, &newsid);
2043                 if (rc)
2044                         return rc;
2045         }
2046
2047         AVC_AUDIT_DATA_INIT(&ad, FS);
2048         ad.u.fs.path = bprm->file->f_path;
2049
2050         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2051                 newsid = tsec->sid;
2052
2053         if (tsec->sid == newsid) {
2054                 rc = avc_has_perm(tsec->sid, isec->sid,
2055                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2056                 if (rc)
2057                         return rc;
2058         } else {
2059                 /* Check permissions for the transition. */
2060                 rc = avc_has_perm(tsec->sid, newsid,
2061                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2062                 if (rc)
2063                         return rc;
2064
2065                 rc = avc_has_perm(newsid, isec->sid,
2066                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2067                 if (rc)
2068                         return rc;
2069
2070                 /* Clear any possibly unsafe personality bits on exec: */
2071                 current->personality &= ~PER_CLEAR_ON_SETID;
2072
2073                 /* Set the security field to the new SID. */
2074                 bsec->sid = newsid;
2075         }
2076
2077         bsec->set = 1;
2078         return 0;
2079 }
2080
2081 static int selinux_bprm_check_security(struct linux_binprm *bprm)
2082 {
2083         return secondary_ops->bprm_check_security(bprm);
2084 }
2085
2086
2087 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2088 {
2089         struct task_security_struct *tsec = current->security;
2090         int atsecure = 0;
2091
2092         if (tsec->osid != tsec->sid) {
2093                 /* Enable secure mode for SIDs transitions unless
2094                    the noatsecure permission is granted between
2095                    the two SIDs, i.e. ahp returns 0. */
2096                 atsecure = avc_has_perm(tsec->osid, tsec->sid,
2097                                          SECCLASS_PROCESS,
2098                                          PROCESS__NOATSECURE, NULL);
2099         }
2100
2101         return (atsecure || secondary_ops->bprm_secureexec(bprm));
2102 }
2103
2104 static void selinux_bprm_free_security(struct linux_binprm *bprm)
2105 {
2106         kfree(bprm->security);
2107         bprm->security = NULL;
2108 }
2109
2110 extern struct vfsmount *selinuxfs_mount;
2111 extern struct dentry *selinux_null;
2112
2113 /* Derived from fs/exec.c:flush_old_files. */
2114 static inline void flush_unauthorized_files(struct files_struct *files)
2115 {
2116         struct avc_audit_data ad;
2117         struct file *file, *devnull = NULL;
2118         struct tty_struct *tty;
2119         struct fdtable *fdt;
2120         long j = -1;
2121         int drop_tty = 0;
2122
2123         mutex_lock(&tty_mutex);
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         }
2142         mutex_unlock(&tty_mutex);
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         int ret = 0;
3554
3555         switch (ad->u.net.family) {
3556         case PF_INET:
3557                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3558                 if (ret || !addrp)
3559                         break;
3560                 *addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3561                                         &ad->u.net.v4info.daddr);
3562                 break;
3563
3564 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3565         case PF_INET6:
3566                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3567                 if (ret || !addrp)
3568                         break;
3569                 *addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3570                                         &ad->u.net.v6info.daddr);
3571                 break;
3572 #endif  /* IPV6 */
3573         default:
3574                 break;
3575         }
3576
3577         if (unlikely(ret))
3578                 printk(KERN_WARNING
3579                        "SELinux: failure in selinux_parse_skb(),"
3580                        " unable to parse packet\n");
3581
3582         return ret;
3583 }
3584
3585 /**
3586  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3587  * @skb: the packet
3588  * @family: protocol family
3589  * @sid: the packet's peer label SID
3590  *
3591  * Description:
3592  * Check the various different forms of network peer labeling and determine
3593  * the peer label/SID for the packet; most of the magic actually occurs in
3594  * the security server function security_net_peersid_cmp().  The function
3595  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3596  * or -EACCES if @sid is invalid due to inconsistencies with the different
3597  * peer labels.
3598  *
3599  */
3600 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3601 {
3602         int err;
3603         u32 xfrm_sid;
3604         u32 nlbl_sid;
3605         u32 nlbl_type;
3606
3607         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3608         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3609
3610         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3611         if (unlikely(err)) {
3612                 printk(KERN_WARNING
3613                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3614                        " unable to determine packet's peer label\n");
3615                 return -EACCES;
3616         }
3617
3618         return 0;
3619 }
3620
3621 /* socket security operations */
3622 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3623                            u32 perms)
3624 {
3625         struct inode_security_struct *isec;
3626         struct task_security_struct *tsec;
3627         struct avc_audit_data ad;
3628         int err = 0;
3629
3630         tsec = task->security;
3631         isec = SOCK_INODE(sock)->i_security;
3632
3633         if (isec->sid == SECINITSID_KERNEL)
3634                 goto out;
3635
3636         AVC_AUDIT_DATA_INIT(&ad, NET);
3637         ad.u.net.sk = sock->sk;
3638         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3639
3640 out:
3641         return err;
3642 }
3643
3644 static int selinux_socket_create(int family, int type,
3645                                  int protocol, int kern)
3646 {
3647         int err = 0;
3648         struct task_security_struct *tsec;
3649         u32 newsid;
3650
3651         if (kern)
3652                 goto out;
3653
3654         tsec = current->security;
3655         newsid = tsec->sockcreate_sid ? : tsec->sid;
3656         err = avc_has_perm(tsec->sid, newsid,
3657                            socket_type_to_security_class(family, type,
3658                            protocol), SOCKET__CREATE, NULL);
3659
3660 out:
3661         return err;
3662 }
3663
3664 static int selinux_socket_post_create(struct socket *sock, int family,
3665                                       int type, int protocol, int kern)
3666 {
3667         int err = 0;
3668         struct inode_security_struct *isec;
3669         struct task_security_struct *tsec;
3670         struct sk_security_struct *sksec;
3671         u32 newsid;
3672
3673         isec = SOCK_INODE(sock)->i_security;
3674
3675         tsec = current->security;
3676         newsid = tsec->sockcreate_sid ? : tsec->sid;
3677         isec->sclass = socket_type_to_security_class(family, type, protocol);
3678         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3679         isec->initialized = 1;
3680
3681         if (sock->sk) {
3682                 sksec = sock->sk->sk_security;
3683                 sksec->sid = isec->sid;
3684                 sksec->sclass = isec->sclass;
3685                 err = selinux_netlbl_socket_post_create(sock);
3686         }
3687
3688         return err;
3689 }
3690
3691 /* Range of port numbers used to automatically bind.
3692    Need to determine whether we should perform a name_bind
3693    permission check between the socket and the port number. */
3694
3695 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3696 {
3697         u16 family;
3698         int err;
3699
3700         err = socket_has_perm(current, sock, SOCKET__BIND);
3701         if (err)
3702                 goto out;
3703
3704         /*
3705          * If PF_INET or PF_INET6, check name_bind permission for the port.
3706          * Multiple address binding for SCTP is not supported yet: we just
3707          * check the first address now.
3708          */
3709         family = sock->sk->sk_family;
3710         if (family == PF_INET || family == PF_INET6) {
3711                 char *addrp;
3712                 struct inode_security_struct *isec;
3713                 struct task_security_struct *tsec;
3714                 struct avc_audit_data ad;
3715                 struct sockaddr_in *addr4 = NULL;
3716                 struct sockaddr_in6 *addr6 = NULL;
3717                 unsigned short snum;
3718                 struct sock *sk = sock->sk;
3719                 u32 sid, node_perm;
3720
3721                 tsec = current->security;
3722                 isec = SOCK_INODE(sock)->i_security;
3723
3724                 if (family == PF_INET) {
3725                         addr4 = (struct sockaddr_in *)address;
3726                         snum = ntohs(addr4->sin_port);
3727                         addrp = (char *)&addr4->sin_addr.s_addr;
3728                 } else {
3729                         addr6 = (struct sockaddr_in6 *)address;
3730                         snum = ntohs(addr6->sin6_port);
3731                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3732                 }
3733
3734                 if (snum) {
3735                         int low, high;
3736
3737                         inet_get_local_port_range(&low, &high);
3738
3739                         if (snum < max(PROT_SOCK, low) || snum > high) {
3740                                 err = sel_netport_sid(sk->sk_protocol,
3741                                                       snum, &sid);
3742                                 if (err)
3743                                         goto out;
3744                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3745                                 ad.u.net.sport = htons(snum);
3746                                 ad.u.net.family = family;
3747                                 err = avc_has_perm(isec->sid, sid,
3748                                                    isec->sclass,
3749                                                    SOCKET__NAME_BIND, &ad);
3750                                 if (err)
3751                                         goto out;
3752                         }
3753                 }
3754
3755                 switch (isec->sclass) {
3756                 case SECCLASS_TCP_SOCKET:
3757                         node_perm = TCP_SOCKET__NODE_BIND;
3758                         break;
3759
3760                 case SECCLASS_UDP_SOCKET:
3761                         node_perm = UDP_SOCKET__NODE_BIND;
3762                         break;
3763
3764                 case SECCLASS_DCCP_SOCKET:
3765                         node_perm = DCCP_SOCKET__NODE_BIND;
3766                         break;
3767
3768                 default:
3769                         node_perm = RAWIP_SOCKET__NODE_BIND;
3770                         break;
3771                 }
3772
3773                 err = sel_netnode_sid(addrp, family, &sid);
3774                 if (err)
3775                         goto out;
3776
3777                 AVC_AUDIT_DATA_INIT(&ad, NET);
3778                 ad.u.net.sport = htons(snum);
3779                 ad.u.net.family = family;
3780
3781                 if (family == PF_INET)
3782                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3783                 else
3784                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3785
3786                 err = avc_has_perm(isec->sid, sid,
3787                                    isec->sclass, node_perm, &ad);
3788                 if (err)
3789                         goto out;
3790         }
3791 out:
3792         return err;
3793 }
3794
3795 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3796 {
3797         struct inode_security_struct *isec;
3798         int err;
3799
3800         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3801         if (err)
3802                 return err;
3803
3804         /*
3805          * If a TCP or DCCP socket, check name_connect permission for the port.
3806          */
3807         isec = SOCK_INODE(sock)->i_security;
3808         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3809             isec->sclass == SECCLASS_DCCP_SOCKET) {
3810                 struct sock *sk = sock->sk;
3811                 struct avc_audit_data ad;
3812                 struct sockaddr_in *addr4 = NULL;
3813                 struct sockaddr_in6 *addr6 = NULL;
3814                 unsigned short snum;
3815                 u32 sid, perm;
3816
3817                 if (sk->sk_family == PF_INET) {
3818                         addr4 = (struct sockaddr_in *)address;
3819                         if (addrlen < sizeof(struct sockaddr_in))
3820                                 return -EINVAL;
3821                         snum = ntohs(addr4->sin_port);
3822                 } else {
3823                         addr6 = (struct sockaddr_in6 *)address;
3824                         if (addrlen < SIN6_LEN_RFC2133)
3825                                 return -EINVAL;
3826                         snum = ntohs(addr6->sin6_port);
3827                 }
3828
3829                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3830                 if (err)
3831                         goto out;
3832
3833                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3834                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3835
3836                 AVC_AUDIT_DATA_INIT(&ad, NET);
3837                 ad.u.net.dport = htons(snum);
3838                 ad.u.net.family = sk->sk_family;
3839                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3840                 if (err)
3841                         goto out;
3842         }
3843
3844 out:
3845         return err;
3846 }
3847
3848 static int selinux_socket_listen(struct socket *sock, int backlog)
3849 {
3850         return socket_has_perm(current, sock, SOCKET__LISTEN);
3851 }
3852
3853 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3854 {
3855         int err;
3856         struct inode_security_struct *isec;
3857         struct inode_security_struct *newisec;
3858
3859         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3860         if (err)
3861                 return err;
3862
3863         newisec = SOCK_INODE(newsock)->i_security;
3864
3865         isec = SOCK_INODE(sock)->i_security;
3866         newisec->sclass = isec->sclass;
3867         newisec->sid = isec->sid;
3868         newisec->initialized = 1;
3869
3870         return 0;
3871 }
3872
3873 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3874                                   int size)
3875 {
3876         int rc;
3877
3878         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3879         if (rc)
3880                 return rc;
3881
3882         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3883 }
3884
3885 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3886                                   int size, int flags)
3887 {
3888         return socket_has_perm(current, sock, SOCKET__READ);
3889 }
3890
3891 static int selinux_socket_getsockname(struct socket *sock)
3892 {
3893         return socket_has_perm(current, sock, SOCKET__GETATTR);
3894 }
3895
3896 static int selinux_socket_getpeername(struct socket *sock)
3897 {
3898         return socket_has_perm(current, sock, SOCKET__GETATTR);
3899 }
3900
3901 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3902 {
3903         int err;
3904
3905         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3906         if (err)
3907                 return err;
3908
3909         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3910 }
3911
3912 static int selinux_socket_getsockopt(struct socket *sock, int level,
3913                                      int optname)
3914 {
3915         return socket_has_perm(current, sock, SOCKET__GETOPT);
3916 }
3917
3918 static int selinux_socket_shutdown(struct socket *sock, int how)
3919 {
3920         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3921 }
3922
3923 static int selinux_socket_unix_stream_connect(struct socket *sock,
3924                                               struct socket *other,
3925                                               struct sock *newsk)
3926 {
3927         struct sk_security_struct *ssec;
3928         struct inode_security_struct *isec;
3929         struct inode_security_struct *other_isec;
3930         struct avc_audit_data ad;
3931         int err;
3932
3933         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3934         if (err)
3935                 return err;
3936
3937         isec = SOCK_INODE(sock)->i_security;
3938         other_isec = SOCK_INODE(other)->i_security;
3939
3940         AVC_AUDIT_DATA_INIT(&ad, NET);
3941         ad.u.net.sk = other->sk;
3942
3943         err = avc_has_perm(isec->sid, other_isec->sid,
3944                            isec->sclass,
3945                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3946         if (err)
3947                 return err;
3948
3949         /* connecting socket */
3950         ssec = sock->sk->sk_security;
3951         ssec->peer_sid = other_isec->sid;
3952
3953         /* server child socket */
3954         ssec = newsk->sk_security;
3955         ssec->peer_sid = isec->sid;
3956         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3957
3958         return err;
3959 }
3960
3961 static int selinux_socket_unix_may_send(struct socket *sock,
3962                                         struct socket *other)
3963 {
3964         struct inode_security_struct *isec;
3965         struct inode_security_struct *other_isec;
3966         struct avc_audit_data ad;
3967         int err;
3968
3969         isec = SOCK_INODE(sock)->i_security;
3970         other_isec = SOCK_INODE(other)->i_security;
3971
3972         AVC_AUDIT_DATA_INIT(&ad, NET);
3973         ad.u.net.sk = other->sk;
3974
3975         err = avc_has_perm(isec->sid, other_isec->sid,
3976                            isec->sclass, SOCKET__SENDTO, &ad);
3977         if (err)
3978                 return err;
3979
3980         return 0;
3981 }
3982
3983 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3984                                     u32 peer_sid,
3985                                     struct avc_audit_data *ad)
3986 {
3987         int err;
3988         u32 if_sid;
3989         u32 node_sid;
3990
3991         err = sel_netif_sid(ifindex, &if_sid);
3992         if (err)
3993                 return err;
3994         err = avc_has_perm(peer_sid, if_sid,
3995                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3996         if (err)
3997                 return err;
3998
3999         err = sel_netnode_sid(addrp, family, &node_sid);
4000         if (err)
4001                 return err;
4002         return avc_has_perm(peer_sid, node_sid,
4003                             SECCLASS_NODE, NODE__RECVFROM, ad);
4004 }
4005
4006 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4007                                                 struct sk_buff *skb,
4008                                                 struct avc_audit_data *ad,
4009                                                 u16 family,
4010                                                 char *addrp)
4011 {
4012         int err;
4013         struct sk_security_struct *sksec = sk->sk_security;
4014         u16 sk_class;
4015         u32 netif_perm, node_perm, recv_perm;
4016         u32 port_sid, node_sid, if_sid, sk_sid;
4017
4018         sk_sid = sksec->sid;
4019         sk_class = sksec->sclass;
4020
4021         switch (sk_class) {
4022         case SECCLASS_UDP_SOCKET:
4023                 netif_perm = NETIF__UDP_RECV;
4024                 node_perm = NODE__UDP_RECV;
4025                 recv_perm = UDP_SOCKET__RECV_MSG;
4026                 break;
4027         case SECCLASS_TCP_SOCKET:
4028                 netif_perm = NETIF__TCP_RECV;
4029                 node_perm = NODE__TCP_RECV;
4030                 recv_perm = TCP_SOCKET__RECV_MSG;
4031                 break;
4032         case SECCLASS_DCCP_SOCKET:
4033                 netif_perm = NETIF__DCCP_RECV;
4034                 node_perm = NODE__DCCP_RECV;
4035                 recv_perm = DCCP_SOCKET__RECV_MSG;
4036                 break;
4037         default:
4038                 netif_perm = NETIF__RAWIP_RECV;
4039                 node_perm = NODE__RAWIP_RECV;
4040                 recv_perm = 0;
4041                 break;
4042         }
4043
4044         err = sel_netif_sid(skb->iif, &if_sid);
4045         if (err)
4046                 return err;
4047         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4048         if (err)
4049                 return err;
4050
4051         err = sel_netnode_sid(addrp, family, &node_sid);
4052         if (err)
4053                 return err;
4054         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4055         if (err)
4056                 return err;
4057
4058         if (!recv_perm)
4059                 return 0;
4060         err = sel_netport_sid(sk->sk_protocol,
4061                               ntohs(ad->u.net.sport), &port_sid);
4062         if (unlikely(err)) {
4063                 printk(KERN_WARNING
4064                        "SELinux: failure in"
4065                        " selinux_sock_rcv_skb_iptables_compat(),"
4066                        " network port label not found\n");
4067                 return err;
4068         }
4069         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4070 }
4071
4072 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4073                                        u16 family)
4074 {
4075         int err;
4076         struct sk_security_struct *sksec = sk->sk_security;
4077         u32 peer_sid;
4078         u32 sk_sid = sksec->sid;
4079         struct avc_audit_data ad;
4080         char *addrp;
4081
4082         AVC_AUDIT_DATA_INIT(&ad, NET);
4083         ad.u.net.netif = skb->iif;
4084         ad.u.net.family = family;
4085         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4086         if (err)
4087                 return err;
4088
4089         if (selinux_compat_net)
4090                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4091                                                            family, addrp);
4092         else
4093                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4094                                    PACKET__RECV, &ad);
4095         if (err)
4096                 return err;
4097
4098         if (selinux_policycap_netpeer) {
4099                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4100                 if (err)
4101                         return err;
4102                 err = avc_has_perm(sk_sid, peer_sid,
4103                                    SECCLASS_PEER, PEER__RECV, &ad);
4104                 if (err)
4105                         selinux_netlbl_err(skb, err, 0);
4106         } else {
4107                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4108                 if (err)
4109                         return err;
4110                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4111         }
4112
4113         return err;
4114 }
4115
4116 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4117 {
4118         int err;
4119         struct sk_security_struct *sksec = sk->sk_security;
4120         u16 family = sk->sk_family;
4121         u32 sk_sid = sksec->sid;
4122         struct avc_audit_data ad;
4123         char *addrp;
4124         u8 secmark_active;
4125         u8 peerlbl_active;
4126
4127         if (family != PF_INET && family != PF_INET6)
4128                 return 0;
4129
4130         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4131         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4132                 family = PF_INET;
4133
4134         /* If any sort of compatibility mode is enabled then handoff processing
4135          * to the selinux_sock_rcv_skb_compat() function to deal with the
4136          * special handling.  We do this in an attempt to keep this function
4137          * as fast and as clean as possible. */
4138         if (selinux_compat_net || !selinux_policycap_netpeer)
4139                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4140
4141         secmark_active = selinux_secmark_enabled();
4142         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4143         if (!secmark_active && !peerlbl_active)
4144                 return 0;
4145
4146         AVC_AUDIT_DATA_INIT(&ad, NET);
4147         ad.u.net.netif = skb->iif;
4148         ad.u.net.family = family;
4149         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4150         if (err)
4151                 return err;
4152
4153         if (peerlbl_active) {
4154                 u32 peer_sid;
4155
4156                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4157                 if (err)
4158                         return err;
4159                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4160                                                peer_sid, &ad);
4161                 if (err) {
4162                         selinux_netlbl_err(skb, err, 0);
4163                         return err;
4164                 }
4165                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4166                                    PEER__RECV, &ad);
4167                 if (err)
4168                         selinux_netlbl_err(skb, err, 0);
4169         }
4170
4171         if (secmark_active) {
4172                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4173                                    PACKET__RECV, &ad);
4174                 if (err)
4175                         return err;
4176         }
4177
4178         return err;
4179 }
4180
4181 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4182                                             int __user *optlen, unsigned len)
4183 {
4184         int err = 0;
4185         char *scontext;
4186         u32 scontext_len;
4187         struct sk_security_struct *ssec;
4188         struct inode_security_struct *isec;
4189         u32 peer_sid = SECSID_NULL;
4190
4191         isec = SOCK_INODE(sock)->i_security;
4192
4193         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4194             isec->sclass == SECCLASS_TCP_SOCKET) {
4195                 ssec = sock->sk->sk_security;
4196                 peer_sid = ssec->peer_sid;
4197         }
4198         if (peer_sid == SECSID_NULL) {
4199                 err = -ENOPROTOOPT;
4200                 goto out;
4201         }
4202
4203         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4204
4205         if (err)
4206                 goto out;
4207
4208         if (scontext_len > len) {
4209                 err = -ERANGE;
4210                 goto out_len;
4211         }
4212
4213         if (copy_to_user(optval, scontext, scontext_len))
4214                 err = -EFAULT;
4215
4216 out_len:
4217         if (put_user(scontext_len, optlen))
4218                 err = -EFAULT;
4219
4220         kfree(scontext);
4221 out:
4222         return err;
4223 }
4224
4225 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4226 {
4227         u32 peer_secid = SECSID_NULL;
4228         u16 family;
4229
4230         if (skb && skb->protocol == htons(ETH_P_IP))
4231                 family = PF_INET;
4232         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4233                 family = PF_INET6;
4234         else if (sock)
4235                 family = sock->sk->sk_family;
4236         else
4237                 goto out;
4238
4239         if (sock && family == PF_UNIX)
4240                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4241         else if (skb)
4242                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4243
4244 out:
4245         *secid = peer_secid;
4246         if (peer_secid == SECSID_NULL)
4247                 return -EINVAL;
4248         return 0;
4249 }
4250
4251 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4252 {
4253         return sk_alloc_security(sk, family, priority);
4254 }
4255
4256 static void selinux_sk_free_security(struct sock *sk)
4257 {
4258         sk_free_security(sk);
4259 }
4260
4261 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4262 {
4263         struct sk_security_struct *ssec = sk->sk_security;
4264         struct sk_security_struct *newssec = newsk->sk_security;
4265
4266         newssec->sid = ssec->sid;
4267         newssec->peer_sid = ssec->peer_sid;
4268         newssec->sclass = ssec->sclass;
4269
4270         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4271 }
4272
4273 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4274 {
4275         if (!sk)
4276                 *secid = SECINITSID_ANY_SOCKET;
4277         else {
4278                 struct sk_security_struct *sksec = sk->sk_security;
4279
4280                 *secid = sksec->sid;
4281         }
4282 }
4283
4284 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4285 {
4286         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4287         struct sk_security_struct *sksec = sk->sk_security;
4288
4289         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4290             sk->sk_family == PF_UNIX)
4291                 isec->sid = sksec->sid;
4292         sksec->sclass = isec->sclass;
4293
4294         selinux_netlbl_sock_graft(sk, parent);
4295 }
4296
4297 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4298                                      struct request_sock *req)
4299 {
4300         struct sk_security_struct *sksec = sk->sk_security;
4301         int err;
4302         u16 family = sk->sk_family;
4303         u32 newsid;
4304         u32 peersid;
4305
4306         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4307         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4308                 family = PF_INET;
4309
4310         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4311         if (err)
4312                 return err;
4313         if (peersid == SECSID_NULL) {
4314                 req->secid = sksec->sid;
4315                 req->peer_secid = SECSID_NULL;
4316                 return 0;
4317         }
4318
4319         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4320         if (err)
4321                 return err;
4322
4323         req->secid = newsid;
4324         req->peer_secid = peersid;
4325         return 0;
4326 }
4327
4328 static void selinux_inet_csk_clone(struct sock *newsk,
4329                                    const struct request_sock *req)
4330 {
4331         struct sk_security_struct *newsksec = newsk->sk_security;
4332
4333         newsksec->sid = req->secid;
4334         newsksec->peer_sid = req->peer_secid;
4335         /* NOTE: Ideally, we should also get the isec->sid for the
4336            new socket in sync, but we don't have the isec available yet.
4337            So we will wait until sock_graft to do it, by which
4338            time it will have been created and available. */
4339
4340         /* We don't need to take any sort of lock here as we are the only
4341          * thread with access to newsksec */
4342         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4343 }
4344
4345 static void selinux_inet_conn_established(struct sock *sk,
4346                                 struct sk_buff *skb)
4347 {
4348         u16 family = sk->sk_family;
4349         struct sk_security_struct *sksec = sk->sk_security;
4350
4351         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4352         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4353                 family = PF_INET;
4354
4355         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4356 }
4357
4358 static void selinux_req_classify_flow(const struct request_sock *req,
4359                                       struct flowi *fl)
4360 {
4361         fl->secid = req->secid;
4362 }
4363
4364 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4365 {
4366         int err = 0;
4367         u32 perm;
4368         struct nlmsghdr *nlh;
4369         struct socket *sock = sk->sk_socket;
4370         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4371
4372         if (skb->len < NLMSG_SPACE(0)) {
4373                 err = -EINVAL;
4374                 goto out;
4375         }
4376         nlh = nlmsg_hdr(skb);
4377
4378         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4379         if (err) {
4380                 if (err == -EINVAL) {
4381                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4382                                   "SELinux:  unrecognized netlink message"
4383                                   " type=%hu for sclass=%hu\n",
4384                                   nlh->nlmsg_type, isec->sclass);
4385                         if (!selinux_enforcing)
4386                                 err = 0;
4387                 }
4388
4389                 /* Ignore */
4390                 if (err == -ENOENT)
4391                         err = 0;
4392                 goto out;
4393         }
4394
4395         err = socket_has_perm(current, sock, perm);
4396 out:
4397         return err;
4398 }
4399
4400 #ifdef CONFIG_NETFILTER
4401
4402 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4403                                        u16 family)
4404 {
4405         int err;
4406         char *addrp;
4407         u32 peer_sid;
4408         struct avc_audit_data ad;
4409         u8 secmark_active;
4410         u8 peerlbl_active;
4411
4412         if (!selinux_policycap_netpeer)
4413                 return NF_ACCEPT;
4414
4415         secmark_active = selinux_secmark_enabled();
4416         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4417         if (!secmark_active && !peerlbl_active)
4418                 return NF_ACCEPT;
4419
4420         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4421                 return NF_DROP;
4422
4423         AVC_AUDIT_DATA_INIT(&ad, NET);
4424         ad.u.net.netif = ifindex;
4425         ad.u.net.family = family;
4426         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4427                 return NF_DROP;
4428
4429         if (peerlbl_active) {
4430                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4431                                                peer_sid, &ad);
4432                 if (err) {
4433                         selinux_netlbl_err(skb, err, 1);
4434                         return NF_DROP;
4435                 }
4436         }
4437
4438         if (secmark_active)
4439                 if (avc_has_perm(peer_sid, skb->secmark,
4440                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4441                         return NF_DROP;
4442
4443         return NF_ACCEPT;
4444 }
4445
4446 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4447                                          struct sk_buff *skb,
4448                                          const struct net_device *in,
4449                                          const struct net_device *out,
4450                                          int (*okfn)(struct sk_buff *))
4451 {
4452         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4453 }
4454
4455 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4456 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4457                                          struct sk_buff *skb,
4458                                          const struct net_device *in,
4459                                          const struct net_device *out,
4460                                          int (*okfn)(struct sk_buff *))
4461 {
4462         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4463 }
4464 #endif  /* IPV6 */
4465
4466 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4467                                                 int ifindex,
4468                                                 struct avc_audit_data *ad,
4469                                                 u16 family, char *addrp)
4470 {
4471         int err;
4472         struct sk_security_struct *sksec = sk->sk_security;
4473         u16 sk_class;
4474         u32 netif_perm, node_perm, send_perm;
4475         u32 port_sid, node_sid, if_sid, sk_sid;
4476
4477         sk_sid = sksec->sid;
4478         sk_class = sksec->sclass;
4479
4480         switch (sk_class) {
4481         case SECCLASS_UDP_SOCKET:
4482                 netif_perm = NETIF__UDP_SEND;
4483                 node_perm = NODE__UDP_SEND;
4484                 send_perm = UDP_SOCKET__SEND_MSG;
4485                 break;
4486         case SECCLASS_TCP_SOCKET:
4487                 netif_perm = NETIF__TCP_SEND;
4488                 node_perm = NODE__TCP_SEND;
4489                 send_perm = TCP_SOCKET__SEND_MSG;
4490                 break;
4491         case SECCLASS_DCCP_SOCKET:
4492                 netif_perm = NETIF__DCCP_SEND;
4493                 node_perm = NODE__DCCP_SEND;
4494                 send_perm = DCCP_SOCKET__SEND_MSG;
4495                 break;
4496         default:
4497                 netif_perm = NETIF__RAWIP_SEND;
4498                 node_perm = NODE__RAWIP_SEND;
4499                 send_perm = 0;
4500                 break;
4501         }
4502
4503         err = sel_netif_sid(ifindex, &if_sid);
4504         if (err)
4505                 return err;
4506         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4507                 return err;
4508
4509         err = sel_netnode_sid(addrp, family, &node_sid);
4510         if (err)
4511                 return err;
4512         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4513         if (err)
4514                 return err;
4515
4516         if (send_perm != 0)
4517                 return 0;
4518
4519         err = sel_netport_sid(sk->sk_protocol,
4520                               ntohs(ad->u.net.dport), &port_sid);
4521         if (unlikely(err)) {
4522                 printk(KERN_WARNING
4523                        "SELinux: failure in"
4524                        " selinux_ip_postroute_iptables_compat(),"
4525                        " network port label not found\n");
4526                 return err;
4527         }
4528         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4529 }
4530
4531 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4532                                                 int ifindex,
4533                                                 u16 family)
4534 {
4535         struct sock *sk = skb->sk;
4536         struct sk_security_struct *sksec;
4537         struct avc_audit_data ad;
4538         char *addrp;
4539         u8 proto;
4540
4541         if (sk == NULL)
4542                 return NF_ACCEPT;
4543         sksec = sk->sk_security;
4544
4545         AVC_AUDIT_DATA_INIT(&ad, NET);
4546         ad.u.net.netif = ifindex;
4547         ad.u.net.family = family;
4548         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4549                 return NF_DROP;
4550
4551         if (selinux_compat_net) {
4552                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4553                                                          &ad, family, addrp))
4554                         return NF_DROP;
4555         } else {
4556                 if (avc_has_perm(sksec->sid, skb->secmark,
4557                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4558                         return NF_DROP;
4559         }
4560
4561         if (selinux_policycap_netpeer)
4562                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4563                         return NF_DROP;
4564
4565         return NF_ACCEPT;
4566 }
4567
4568 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4569                                          u16 family)
4570 {
4571         u32 secmark_perm;
4572         u32 peer_sid;
4573         struct sock *sk;
4574         struct avc_audit_data ad;
4575         char *addrp;
4576         u8 secmark_active;
4577         u8 peerlbl_active;
4578
4579         /* If any sort of compatibility mode is enabled then handoff processing
4580          * to the selinux_ip_postroute_compat() function to deal with the
4581          * special handling.  We do this in an attempt to keep this function
4582          * as fast and as clean as possible. */
4583         if (selinux_compat_net || !selinux_policycap_netpeer)
4584                 return selinux_ip_postroute_compat(skb, ifindex, family);
4585
4586         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4587          * packet transformation so allow the packet to pass without any checks
4588          * since we'll have another chance to perform access control checks
4589          * when the packet is on it's final way out.
4590          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4591          *       is NULL, in this case go ahead and apply access control. */
4592         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4593                 return NF_ACCEPT;
4594
4595         secmark_active = selinux_secmark_enabled();
4596         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4597         if (!secmark_active && !peerlbl_active)
4598                 return NF_ACCEPT;
4599
4600         /* if the packet is being forwarded then get the peer label from the
4601          * packet itself; otherwise check to see if it is from a local
4602          * application or the kernel, if from an application get the peer label
4603          * from the sending socket, otherwise use the kernel's sid */
4604         sk = skb->sk;
4605         if (sk == NULL) {
4606                 switch (family) {
4607                 case PF_INET:
4608                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4609                                 secmark_perm = PACKET__FORWARD_OUT;
4610                         else
4611                                 secmark_perm = PACKET__SEND;
4612                         break;
4613                 case PF_INET6:
4614                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4615                                 secmark_perm = PACKET__FORWARD_OUT;
4616                         else
4617                                 secmark_perm = PACKET__SEND;
4618                         break;
4619                 default:
4620                         return NF_DROP;
4621                 }
4622                 if (secmark_perm == PACKET__FORWARD_OUT) {
4623                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4624                                 return NF_DROP;
4625                 } else
4626                         peer_sid = SECINITSID_KERNEL;
4627         } else {
4628                 struct sk_security_struct *sksec = sk->sk_security;
4629                 peer_sid = sksec->sid;
4630                 secmark_perm = PACKET__SEND;
4631         }
4632
4633         AVC_AUDIT_DATA_INIT(&ad, NET);
4634         ad.u.net.netif = ifindex;
4635         ad.u.net.family = family;
4636         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4637                 return NF_DROP;
4638
4639         if (secmark_active)
4640                 if (avc_has_perm(peer_sid, skb->secmark,
4641                                  SECCLASS_PACKET, secmark_perm, &ad))
4642                         return NF_DROP;
4643
4644         if (peerlbl_active) {
4645                 u32 if_sid;
4646                 u32 node_sid;
4647
4648                 if (sel_netif_sid(ifindex, &if_sid))
4649                         return NF_DROP;
4650                 if (avc_has_perm(peer_sid, if_sid,
4651                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4652                         return NF_DROP;
4653
4654                 if (sel_netnode_sid(addrp, family, &node_sid))
4655                         return NF_DROP;
4656                 if (avc_has_perm(peer_sid, node_sid,
4657                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4658                         return NF_DROP;
4659         }
4660
4661         return NF_ACCEPT;
4662 }
4663
4664 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4665                                            struct sk_buff *skb,
4666                                            const struct net_device *in,
4667                                            const struct net_device *out,
4668                                            int (*okfn)(struct sk_buff *))
4669 {
4670         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4671 }
4672
4673 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4674 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4675                                            struct sk_buff *skb,
4676                                            const struct net_device *in,
4677                                            const struct net_device *out,
4678                                            int (*okfn)(struct sk_buff *))
4679 {
4680         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4681 }
4682 #endif  /* IPV6 */
4683
4684 #endif  /* CONFIG_NETFILTER */
4685
4686 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4687 {
4688         int err;
4689
4690         err = secondary_ops->netlink_send(sk, skb);
4691         if (err)
4692                 return err;
4693
4694         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4695                 err = selinux_nlmsg_perm(sk, skb);
4696
4697         return err;
4698 }
4699
4700 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4701 {
4702         int err;
4703         struct avc_audit_data ad;
4704
4705         err = secondary_ops->netlink_recv(skb, capability);
4706         if (err)
4707                 return err;
4708
4709         AVC_AUDIT_DATA_INIT(&ad, CAP);
4710         ad.u.cap = capability;
4711
4712         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4713                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4714 }
4715
4716 static int ipc_alloc_security(struct task_struct *task,
4717                               struct kern_ipc_perm *perm,
4718                               u16 sclass)
4719 {
4720         struct task_security_struct *tsec = task->security;
4721         struct ipc_security_struct *isec;
4722
4723         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4724         if (!isec)
4725                 return -ENOMEM;
4726
4727         isec->sclass = sclass;
4728         isec->sid = tsec->sid;
4729         perm->security = isec;
4730
4731         return 0;
4732 }
4733
4734 static void ipc_free_security(struct kern_ipc_perm *perm)
4735 {
4736         struct ipc_security_struct *isec = perm->security;
4737         perm->security = NULL;
4738         kfree(isec);
4739 }
4740
4741 static int msg_msg_alloc_security(struct msg_msg *msg)
4742 {
4743         struct msg_security_struct *msec;
4744
4745         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4746         if (!msec)
4747                 return -ENOMEM;
4748
4749         msec->sid = SECINITSID_UNLABELED;
4750         msg->security = msec;
4751
4752         return 0;
4753 }
4754
4755 static void msg_msg_free_security(struct msg_msg *msg)
4756 {
4757         struct msg_security_struct *msec = msg->security;
4758
4759         msg->security = NULL;
4760         kfree(msec);
4761 }
4762
4763 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4764                         u32 perms)
4765 {
4766         struct task_security_struct *tsec;
4767         struct ipc_security_struct *isec;
4768         struct avc_audit_data ad;
4769
4770         tsec = current->security;
4771         isec = ipc_perms->security;
4772
4773         AVC_AUDIT_DATA_INIT(&ad, IPC);
4774         ad.u.ipc_id = ipc_perms->key;
4775
4776         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
4777 }
4778
4779 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4780 {
4781         return msg_msg_alloc_security(msg);
4782 }
4783
4784 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4785 {
4786         msg_msg_free_security(msg);
4787 }
4788
4789 /* message queue security operations */
4790 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4791 {
4792         struct task_security_struct *tsec;
4793         struct ipc_security_struct *isec;
4794         struct avc_audit_data ad;
4795         int rc;
4796
4797         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4798         if (rc)
4799                 return rc;
4800
4801         tsec = current->security;
4802         isec = msq->q_perm.security;
4803
4804         AVC_AUDIT_DATA_INIT(&ad, IPC);
4805         ad.u.ipc_id = msq->q_perm.key;
4806
4807         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4808                           MSGQ__CREATE, &ad);
4809         if (rc) {
4810                 ipc_free_security(&msq->q_perm);
4811                 return rc;
4812         }
4813         return 0;
4814 }
4815
4816 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4817 {
4818         ipc_free_security(&msq->q_perm);
4819 }
4820
4821 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4822 {
4823         struct task_security_struct *tsec;
4824         struct ipc_security_struct *isec;
4825         struct avc_audit_data ad;
4826
4827         tsec = current->security;
4828         isec = msq->q_perm.security;
4829
4830         AVC_AUDIT_DATA_INIT(&ad, IPC);
4831         ad.u.ipc_id = msq->q_perm.key;
4832
4833         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4834                             MSGQ__ASSOCIATE, &ad);
4835 }
4836
4837 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4838 {
4839         int err;
4840         int perms;
4841
4842         switch (cmd) {
4843         case IPC_INFO:
4844         case MSG_INFO:
4845                 /* No specific object, just general system-wide information. */
4846                 return task_has_system(current, SYSTEM__IPC_INFO);
4847         case IPC_STAT:
4848         case MSG_STAT:
4849                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4850                 break;
4851         case IPC_SET:
4852                 perms = MSGQ__SETATTR;
4853                 break;
4854         case IPC_RMID:
4855                 perms = MSGQ__DESTROY;
4856                 break;
4857         default:
4858                 return 0;
4859         }
4860
4861         err = ipc_has_perm(&msq->q_perm, perms);
4862         return err;
4863 }
4864
4865 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4866 {
4867         struct task_security_struct *tsec;
4868         struct ipc_security_struct *isec;
4869         struct msg_security_struct *msec;
4870         struct avc_audit_data ad;
4871         int rc;
4872
4873         tsec = current->security;
4874         isec = msq->q_perm.security;
4875         msec = msg->security;
4876
4877         /*
4878          * First time through, need to assign label to the message
4879          */
4880         if (msec->sid == SECINITSID_UNLABELED) {
4881                 /*
4882                  * Compute new sid based on current process and
4883                  * message queue this message will be stored in
4884                  */
4885                 rc = security_transition_sid(tsec->sid,
4886                                              isec->sid,
4887                                              SECCLASS_MSG,
4888                                              &msec->sid);
4889                 if (rc)
4890                         return rc;
4891         }
4892
4893         AVC_AUDIT_DATA_INIT(&ad, IPC);
4894         ad.u.ipc_id = msq->q_perm.key;
4895
4896         /* Can this process write to the queue? */
4897         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4898                           MSGQ__WRITE, &ad);
4899         if (!rc)
4900                 /* Can this process send the message */
4901                 rc = avc_has_perm(tsec->sid, msec->sid,
4902                                   SECCLASS_MSG, MSG__SEND, &ad);
4903         if (!rc)
4904                 /* Can the message be put in the queue? */
4905                 rc = avc_has_perm(msec->sid, isec->sid,
4906                                   SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
4907
4908         return rc;
4909 }
4910
4911 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4912                                     struct task_struct *target,
4913                                     long type, int mode)
4914 {
4915         struct task_security_struct *tsec;
4916         struct ipc_security_struct *isec;
4917         struct msg_security_struct *msec;
4918         struct avc_audit_data ad;
4919         int rc;
4920
4921         tsec = target->security;
4922         isec = msq->q_perm.security;
4923         msec = msg->security;
4924
4925         AVC_AUDIT_DATA_INIT(&ad, IPC);
4926         ad.u.ipc_id = msq->q_perm.key;
4927
4928         rc = avc_has_perm(tsec->sid, isec->sid,
4929                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4930         if (!rc)
4931                 rc = avc_has_perm(tsec->sid, msec->sid,
4932                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4933         return rc;
4934 }
4935
4936 /* Shared Memory security operations */
4937 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4938 {
4939         struct task_security_struct *tsec;
4940         struct ipc_security_struct *isec;
4941         struct avc_audit_data ad;
4942         int rc;
4943
4944         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4945         if (rc)
4946                 return rc;
4947
4948         tsec = current->security;
4949         isec = shp->shm_perm.security;
4950
4951         AVC_AUDIT_DATA_INIT(&ad, IPC);
4952         ad.u.ipc_id = shp->shm_perm.key;
4953
4954         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4955                           SHM__CREATE, &ad);
4956         if (rc) {
4957                 ipc_free_security(&shp->shm_perm);
4958                 return rc;
4959         }
4960         return 0;
4961 }
4962
4963 static void selinux_shm_free_security(struct shmid_kernel *shp)
4964 {
4965         ipc_free_security(&shp->shm_perm);
4966 }
4967
4968 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4969 {
4970         struct task_security_struct *tsec;
4971         struct ipc_security_struct *isec;
4972         struct avc_audit_data ad;
4973
4974         tsec = current->security;
4975         isec = shp->shm_perm.security;
4976
4977         AVC_AUDIT_DATA_INIT(&ad, IPC);
4978         ad.u.ipc_id = shp->shm_perm.key;
4979
4980         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4981                             SHM__ASSOCIATE, &ad);
4982 }
4983
4984 /* Note, at this point, shp is locked down */
4985 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4986 {
4987         int perms;
4988         int err;
4989
4990         switch (cmd) {
4991         case IPC_INFO:
4992         case SHM_INFO:
4993                 /* No specific object, just general system-wide information. */
4994                 return task_has_system(current, SYSTEM__IPC_INFO);
4995         case IPC_STAT:
4996         case SHM_STAT:
4997                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4998                 break;
4999         case IPC_SET:
5000                 perms = SHM__SETATTR;
5001                 break;
5002         case SHM_LOCK:
5003         case SHM_UNLOCK:
5004                 perms = SHM__LOCK;
5005                 break;
5006         case IPC_RMID:
5007                 perms = SHM__DESTROY;
5008                 break;
5009         default:
5010                 return 0;
5011         }
5012
5013         err = ipc_has_perm(&shp->shm_perm, perms);
5014         return err;
5015 }
5016
5017 static int selinux_shm_shmat(struct shmid_kernel *shp,
5018                              char __user *shmaddr, int shmflg)
5019 {
5020         u32 perms;
5021         int rc;
5022
5023         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
5024         if (rc)
5025                 return rc;
5026
5027         if (shmflg & SHM_RDONLY)
5028                 perms = SHM__READ;
5029         else
5030                 perms = SHM__READ | SHM__WRITE;
5031
5032         return ipc_has_perm(&shp->shm_perm, perms);
5033 }
5034
5035 /* Semaphore security operations */
5036 static int selinux_sem_alloc_security(struct sem_array *sma)
5037 {
5038         struct task_security_struct *tsec;
5039         struct ipc_security_struct *isec;
5040         struct avc_audit_data ad;
5041         int rc;
5042
5043         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5044         if (rc)
5045                 return rc;
5046
5047         tsec = current->security;
5048         isec = sma->sem_perm.security;
5049
5050         AVC_AUDIT_DATA_INIT(&ad, IPC);
5051         ad.u.ipc_id = sma->sem_perm.key;
5052
5053         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
5054                           SEM__CREATE, &ad);
5055         if (rc) {
5056                 ipc_free_security(&sma->sem_perm);
5057                 return rc;
5058         }
5059         return 0;
5060 }
5061
5062 static void selinux_sem_free_security(struct sem_array *sma)
5063 {
5064         ipc_free_security(&sma->sem_perm);
5065 }
5066
5067 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5068 {
5069         struct task_security_struct *tsec;
5070         struct ipc_security_struct *isec;
5071         struct avc_audit_data ad;
5072
5073         tsec = current->security;
5074         isec = sma->sem_perm.security;
5075
5076         AVC_AUDIT_DATA_INIT(&ad, IPC);
5077         ad.u.ipc_id = sma->sem_perm.key;
5078
5079         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
5080                             SEM__ASSOCIATE, &ad);
5081 }
5082
5083 /* Note, at this point, sma is locked down */
5084 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5085 {
5086         int err;
5087         u32 perms;
5088
5089         switch (cmd) {
5090         case IPC_INFO:
5091         case SEM_INFO:
5092                 /* No specific object, just general system-wide information. */
5093                 return task_has_system(current, SYSTEM__IPC_INFO);
5094         case GETPID:
5095         case GETNCNT:
5096         case GETZCNT:
5097                 perms = SEM__GETATTR;
5098                 break;
5099         case GETVAL:
5100         case GETALL:
5101                 perms = SEM__READ;
5102                 break;
5103         case SETVAL:
5104         case SETALL:
5105                 perms = SEM__WRITE;
5106                 break;
5107         case IPC_RMID:
5108                 perms = SEM__DESTROY;
5109                 break;
5110         case IPC_SET:
5111                 perms = SEM__SETATTR;
5112                 break;
5113         case IPC_STAT:
5114         case SEM_STAT:
5115                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5116                 break;
5117         default:
5118                 return 0;
5119         }
5120
5121         err = ipc_has_perm(&sma->sem_perm, perms);
5122         return err;
5123 }
5124
5125 static int selinux_sem_semop(struct sem_array *sma,
5126                              struct sembuf *sops, unsigned nsops, int alter)
5127 {
5128         u32 perms;
5129
5130         if (alter)
5131                 perms = SEM__READ | SEM__WRITE;
5132         else
5133                 perms = SEM__READ;
5134
5135         return ipc_has_perm(&sma->sem_perm, perms);
5136 }
5137
5138 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5139 {
5140         u32 av = 0;
5141
5142         av = 0;
5143         if (flag & S_IRUGO)
5144                 av |= IPC__UNIX_READ;
5145         if (flag & S_IWUGO)
5146                 av |= IPC__UNIX_WRITE;
5147
5148         if (av == 0)
5149                 return 0;
5150
5151         return ipc_has_perm(ipcp, av);
5152 }
5153
5154 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5155 {
5156         struct ipc_security_struct *isec = ipcp->security;
5157         *secid = isec->sid;
5158 }
5159
5160 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5161 {
5162         if (inode)
5163                 inode_doinit_with_dentry(inode, dentry);
5164 }
5165
5166 static int selinux_getprocattr(struct task_struct *p,
5167                                char *name, char **value)
5168 {
5169         struct task_security_struct *tsec;
5170         u32 sid;
5171         int error;
5172         unsigned len;
5173
5174         if (current != p) {
5175                 error = task_has_perm(current, p, PROCESS__GETATTR);
5176                 if (error)
5177                         return error;
5178         }
5179
5180         tsec = p->security;
5181
5182         if (!strcmp(name, "current"))
5183                 sid = tsec->sid;
5184         else if (!strcmp(name, "prev"))
5185                 sid = tsec->osid;
5186         else if (!strcmp(name, "exec"))
5187                 sid = tsec->exec_sid;
5188         else if (!strcmp(name, "fscreate"))
5189                 sid = tsec->create_sid;
5190         else if (!strcmp(name, "keycreate"))
5191                 sid = tsec->keycreate_sid;
5192         else if (!strcmp(name, "sockcreate"))
5193                 sid = tsec->sockcreate_sid;
5194         else
5195                 return -EINVAL;
5196
5197         if (!sid)
5198                 return 0;
5199
5200         error = security_sid_to_context(sid, value, &len);
5201         if (error)
5202                 return error;
5203         return len;
5204 }
5205
5206 static int selinux_setprocattr(struct task_struct *p,
5207                                char *name, void *value, size_t size)
5208 {
5209         struct task_security_struct *tsec;
5210         struct task_struct *tracer;
5211         u32 sid = 0;
5212         int error;
5213         char *str = value;
5214
5215         if (current != p) {
5216                 /* SELinux only allows a process to change its own
5217                    security attributes. */
5218                 return -EACCES;
5219         }
5220
5221         /*
5222          * Basic control over ability to set these attributes at all.
5223          * current == p, but we'll pass them separately in case the
5224          * above restriction is ever removed.
5225          */
5226         if (!strcmp(name, "exec"))
5227                 error = task_has_perm(current, p, PROCESS__SETEXEC);
5228         else if (!strcmp(name, "fscreate"))
5229                 error = task_has_perm(current, p, PROCESS__SETFSCREATE);
5230         else if (!strcmp(name, "keycreate"))
5231                 error = task_has_perm(current, p, PROCESS__SETKEYCREATE);
5232         else if (!strcmp(name, "sockcreate"))
5233                 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE);
5234         else if (!strcmp(name, "current"))
5235                 error = task_has_perm(current, p, PROCESS__SETCURRENT);
5236         else
5237                 error = -EINVAL;
5238         if (error)
5239                 return error;
5240
5241         /* Obtain a SID for the context, if one was specified. */
5242         if (size && str[1] && str[1] != '\n') {
5243                 if (str[size-1] == '\n') {
5244                         str[size-1] = 0;
5245                         size--;
5246                 }
5247                 error = security_context_to_sid(value, size, &sid);
5248                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5249                         if (!capable(CAP_MAC_ADMIN))
5250                                 return error;
5251                         error = security_context_to_sid_force(value, size,
5252                                                               &sid);
5253                 }
5254                 if (error)
5255                         return error;
5256         }
5257
5258         /* Permission checking based on the specified context is
5259            performed during the actual operation (execve,
5260            open/mkdir/...), when we know the full context of the
5261            operation.  See selinux_bprm_set_security for the execve
5262            checks and may_create for the file creation checks. The
5263            operation will then fail if the context is not permitted. */
5264         tsec = p->security;
5265         if (!strcmp(name, "exec"))
5266                 tsec->exec_sid = sid;
5267         else if (!strcmp(name, "fscreate"))
5268                 tsec->create_sid = sid;
5269         else if (!strcmp(name, "keycreate")) {
5270                 error = may_create_key(sid, p);
5271                 if (error)
5272                         return error;
5273                 tsec->keycreate_sid = sid;
5274         } else if (!strcmp(name, "sockcreate"))
5275                 tsec->sockcreate_sid = sid;
5276         else if (!strcmp(name, "current")) {
5277                 struct av_decision avd;
5278
5279                 if (sid == 0)
5280                         return -EINVAL;
5281
5282                 /* Only allow single threaded processes to change context */
5283                 if (atomic_read(&p->mm->mm_users) != 1) {
5284                         struct task_struct *g, *t;
5285                         struct mm_struct *mm = p->mm;
5286                         read_lock(&tasklist_lock);
5287                         do_each_thread(g, t) {
5288                                 if (t->mm == mm && t != p) {
5289                                         read_unlock(&tasklist_lock);
5290                                         return -EPERM;
5291                                 }
5292                         } while_each_thread(g, t);
5293                         read_unlock(&tasklist_lock);
5294                 }
5295
5296                 /* Check permissions for the transition. */
5297                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5298                                      PROCESS__DYNTRANSITION, NULL);
5299                 if (error)
5300                         return error;
5301
5302                 /* Check for ptracing, and update the task SID if ok.
5303                    Otherwise, leave SID unchanged and fail. */
5304                 task_lock(p);
5305                 rcu_read_lock();
5306                 tracer = tracehook_tracer_task(p);
5307                 if (tracer != NULL) {
5308                         struct task_security_struct *ptsec = tracer->security;
5309                         u32 ptsid = ptsec->sid;
5310                         rcu_read_unlock();
5311                         error = avc_has_perm_noaudit(ptsid, sid,
5312                                                      SECCLASS_PROCESS,
5313                                                      PROCESS__PTRACE, 0, &avd);
5314                         if (!error)
5315                                 tsec->sid = sid;
5316                         task_unlock(p);
5317                         avc_audit(ptsid, sid, SECCLASS_PROCESS,
5318                                   PROCESS__PTRACE, &avd, error, NULL);
5319                         if (error)
5320                                 return error;
5321                 } else {
5322                         rcu_read_unlock();
5323                         tsec->sid = sid;
5324                         task_unlock(p);
5325                 }
5326         } else
5327                 return -EINVAL;
5328
5329         return size;
5330 }
5331
5332 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5333 {
5334         return security_sid_to_context(secid, secdata, seclen);
5335 }
5336
5337 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5338 {
5339         return security_context_to_sid(secdata, seclen, secid);
5340 }
5341
5342 static void selinux_release_secctx(char *secdata, u32 seclen)
5343 {
5344         kfree(secdata);
5345 }
5346
5347 #ifdef CONFIG_KEYS
5348
5349 static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
5350                              unsigned long flags)
5351 {
5352         struct task_security_struct *tsec = tsk->security;
5353         struct key_security_struct *ksec;
5354
5355         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5356         if (!ksec)
5357                 return -ENOMEM;
5358
5359         if (tsec->keycreate_sid)
5360                 ksec->sid = tsec->keycreate_sid;
5361         else
5362                 ksec->sid = tsec->sid;
5363         k->security = ksec;
5364
5365         return 0;
5366 }
5367
5368 static void selinux_key_free(struct key *k)
5369 {
5370         struct key_security_struct *ksec = k->security;
5371
5372         k->security = NULL;
5373         kfree(ksec);
5374 }
5375
5376 static int selinux_key_permission(key_ref_t key_ref,
5377                             struct task_struct *ctx,
5378                             key_perm_t perm)
5379 {
5380         struct key *key;
5381         struct task_security_struct *tsec;
5382         struct key_security_struct *ksec;
5383
5384         key = key_ref_to_ptr(key_ref);
5385
5386         tsec = ctx->security;
5387         ksec = key->security;
5388
5389         /* if no specific permissions are requested, we skip the
5390            permission check. No serious, additional covert channels
5391            appear to be created. */
5392         if (perm == 0)
5393                 return 0;
5394
5395         return avc_has_perm(tsec->sid, ksec->sid,
5396                             SECCLASS_KEY, perm, NULL);
5397 }
5398
5399 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5400 {
5401         struct key_security_struct *ksec = key->security;
5402         char *context = NULL;
5403         unsigned len;
5404         int rc;
5405
5406         rc = security_sid_to_context(ksec->sid, &context, &len);
5407         if (!rc)
5408                 rc = len;
5409         *_buffer = context;
5410         return rc;
5411 }
5412
5413 #endif
5414
5415 static struct security_operations selinux_ops = {
5416         .name =                         "selinux",
5417
5418         .ptrace_may_access =            selinux_ptrace_may_access,
5419         .ptrace_traceme =               selinux_ptrace_traceme,
5420         .capget =                       selinux_capget,
5421         .capset_check =                 selinux_capset_check,
5422         .capset_set =                   selinux_capset_set,
5423         .sysctl =                       selinux_sysctl,
5424         .capable =                      selinux_capable,
5425         .quotactl =                     selinux_quotactl,
5426         .quota_on =                     selinux_quota_on,
5427         .syslog =                       selinux_syslog,
5428         .vm_enough_memory =             selinux_vm_enough_memory,
5429
5430         .netlink_send =                 selinux_netlink_send,
5431         .netlink_recv =                 selinux_netlink_recv,
5432
5433         .bprm_alloc_security =          selinux_bprm_alloc_security,
5434         .bprm_free_security =           selinux_bprm_free_security,
5435         .bprm_apply_creds =             selinux_bprm_apply_creds,
5436         .bprm_post_apply_creds =        selinux_bprm_post_apply_creds,
5437         .bprm_set_security =            selinux_bprm_set_security,
5438         .bprm_check_security =          selinux_bprm_check_security,
5439         .bprm_secureexec =              selinux_bprm_secureexec,
5440
5441         .sb_alloc_security =            selinux_sb_alloc_security,
5442         .sb_free_security =             selinux_sb_free_security,
5443         .sb_copy_data =                 selinux_sb_copy_data,
5444         .sb_kern_mount =                selinux_sb_kern_mount,
5445         .sb_show_options =              selinux_sb_show_options,
5446         .sb_statfs =                    selinux_sb_statfs,
5447         .sb_mount =                     selinux_mount,
5448         .sb_umount =                    selinux_umount,
5449         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5450         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5451         .sb_parse_opts_str =            selinux_parse_opts_str,
5452
5453
5454         .inode_alloc_security =         selinux_inode_alloc_security,
5455         .inode_free_security =          selinux_inode_free_security,
5456         .inode_init_security =          selinux_inode_init_security,
5457         .inode_create =                 selinux_inode_create,
5458         .inode_link =                   selinux_inode_link,
5459         .inode_unlink =                 selinux_inode_unlink,
5460         .inode_symlink =                selinux_inode_symlink,
5461         .inode_mkdir =                  selinux_inode_mkdir,
5462         .inode_rmdir =                  selinux_inode_rmdir,
5463         .inode_mknod =                  selinux_inode_mknod,
5464         .inode_rename =                 selinux_inode_rename,
5465         .inode_readlink =               selinux_inode_readlink,
5466         .inode_follow_link =            selinux_inode_follow_link,
5467         .inode_permission =             selinux_inode_permission,
5468         .inode_setattr =                selinux_inode_setattr,
5469         .inode_getattr =                selinux_inode_getattr,
5470         .inode_setxattr =               selinux_inode_setxattr,
5471         .inode_post_setxattr =          selinux_inode_post_setxattr,
5472         .inode_getxattr =               selinux_inode_getxattr,
5473         .inode_listxattr =              selinux_inode_listxattr,
5474         .inode_removexattr =            selinux_inode_removexattr,
5475         .inode_getsecurity =            selinux_inode_getsecurity,
5476         .inode_setsecurity =            selinux_inode_setsecurity,
5477         .inode_listsecurity =           selinux_inode_listsecurity,
5478         .inode_need_killpriv =          selinux_inode_need_killpriv,
5479         .inode_killpriv =               selinux_inode_killpriv,
5480         .inode_getsecid =               selinux_inode_getsecid,
5481
5482         .file_permission =              selinux_file_permission,
5483         .file_alloc_security =          selinux_file_alloc_security,
5484         .file_free_security =           selinux_file_free_security,
5485         .file_ioctl =                   selinux_file_ioctl,
5486         .file_mmap =                    selinux_file_mmap,
5487         .file_mprotect =                selinux_file_mprotect,
5488         .file_lock =                    selinux_file_lock,
5489         .file_fcntl =                   selinux_file_fcntl,
5490         .file_set_fowner =              selinux_file_set_fowner,
5491         .file_send_sigiotask =          selinux_file_send_sigiotask,
5492         .file_receive =                 selinux_file_receive,
5493
5494         .dentry_open =                  selinux_dentry_open,
5495
5496         .task_create =                  selinux_task_create,
5497         .task_alloc_security =          selinux_task_alloc_security,
5498         .task_free_security =           selinux_task_free_security,
5499         .task_setuid =                  selinux_task_setuid,
5500         .task_post_setuid =             selinux_task_post_setuid,
5501         .task_setgid =                  selinux_task_setgid,
5502         .task_setpgid =                 selinux_task_setpgid,
5503         .task_getpgid =                 selinux_task_getpgid,
5504         .task_getsid =                  selinux_task_getsid,
5505         .task_getsecid =                selinux_task_getsecid,
5506         .task_setgroups =               selinux_task_setgroups,
5507         .task_setnice =                 selinux_task_setnice,
5508         .task_setioprio =               selinux_task_setioprio,
5509         .task_getioprio =               selinux_task_getioprio,
5510         .task_setrlimit =               selinux_task_setrlimit,
5511         .task_setscheduler =            selinux_task_setscheduler,
5512         .task_getscheduler =            selinux_task_getscheduler,
5513         .task_movememory =              selinux_task_movememory,
5514         .task_kill =                    selinux_task_kill,
5515         .task_wait =                    selinux_task_wait,
5516         .task_prctl =                   selinux_task_prctl,
5517         .task_reparent_to_init =        selinux_task_reparent_to_init,
5518         .task_to_inode =                selinux_task_to_inode,
5519
5520         .ipc_permission =               selinux_ipc_permission,
5521         .ipc_getsecid =                 selinux_ipc_getsecid,
5522
5523         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5524         .msg_msg_free_security =        selinux_msg_msg_free_security,
5525
5526         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5527         .msg_queue_free_security =      selinux_msg_queue_free_security,
5528         .msg_queue_associate =          selinux_msg_queue_associate,
5529         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5530         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5531         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5532
5533         .shm_alloc_security =           selinux_shm_alloc_security,
5534         .shm_free_security =            selinux_shm_free_security,
5535         .shm_associate =                selinux_shm_associate,
5536         .shm_shmctl =                   selinux_shm_shmctl,
5537         .shm_shmat =                    selinux_shm_shmat,
5538
5539         .sem_alloc_security =           selinux_sem_alloc_security,
5540         .sem_free_security =            selinux_sem_free_security,
5541         .sem_associate =                selinux_sem_associate,
5542         .sem_semctl =                   selinux_sem_semctl,
5543         .sem_semop =                    selinux_sem_semop,
5544
5545         .d_instantiate =                selinux_d_instantiate,
5546
5547         .getprocattr =                  selinux_getprocattr,
5548         .setprocattr =                  selinux_setprocattr,
5549
5550         .secid_to_secctx =              selinux_secid_to_secctx,
5551         .secctx_to_secid =              selinux_secctx_to_secid,
5552         .release_secctx =               selinux_release_secctx,
5553
5554         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5555         .unix_may_send =                selinux_socket_unix_may_send,
5556
5557         .socket_create =                selinux_socket_create,
5558         .socket_post_create =           selinux_socket_post_create,
5559         .socket_bind =                  selinux_socket_bind,
5560         .socket_connect =               selinux_socket_connect,
5561         .socket_listen =                selinux_socket_listen,
5562         .socket_accept =                selinux_socket_accept,
5563         .socket_sendmsg =               selinux_socket_sendmsg,
5564         .socket_recvmsg =               selinux_socket_recvmsg,
5565         .socket_getsockname =           selinux_socket_getsockname,
5566         .socket_getpeername =           selinux_socket_getpeername,
5567         .socket_getsockopt =            selinux_socket_getsockopt,
5568         .socket_setsockopt =            selinux_socket_setsockopt,
5569         .socket_shutdown =              selinux_socket_shutdown,
5570         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5571         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5572         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5573         .sk_alloc_security =            selinux_sk_alloc_security,
5574         .sk_free_security =             selinux_sk_free_security,
5575         .sk_clone_security =            selinux_sk_clone_security,
5576         .sk_getsecid =                  selinux_sk_getsecid,
5577         .sock_graft =                   selinux_sock_graft,
5578         .inet_conn_request =            selinux_inet_conn_request,
5579         .inet_csk_clone =               selinux_inet_csk_clone,
5580         .inet_conn_established =        selinux_inet_conn_established,
5581         .req_classify_flow =            selinux_req_classify_flow,
5582
5583 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5584         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5585         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5586         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5587         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5588         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5589         .xfrm_state_free_security =     selinux_xfrm_state_free,
5590         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5591         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5592         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5593         .xfrm_decode_session =          selinux_xfrm_decode_session,
5594 #endif
5595
5596 #ifdef CONFIG_KEYS
5597         .key_alloc =                    selinux_key_alloc,
5598         .key_free =                     selinux_key_free,
5599         .key_permission =               selinux_key_permission,
5600         .key_getsecurity =              selinux_key_getsecurity,
5601 #endif
5602
5603 #ifdef CONFIG_AUDIT
5604         .audit_rule_init =              selinux_audit_rule_init,
5605         .audit_rule_known =             selinux_audit_rule_known,
5606         .audit_rule_match =             selinux_audit_rule_match,
5607         .audit_rule_free =              selinux_audit_rule_free,
5608 #endif
5609 };
5610
5611 static __init int selinux_init(void)
5612 {
5613         struct task_security_struct *tsec;
5614
5615         if (!security_module_enable(&selinux_ops)) {
5616                 selinux_enabled = 0;
5617                 return 0;
5618         }
5619
5620         if (!selinux_enabled) {
5621                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5622                 return 0;
5623         }
5624
5625         printk(KERN_INFO "SELinux:  Initializing.\n");
5626
5627         /* Set the security state for the initial task. */
5628         if (task_alloc_security(current))
5629                 panic("SELinux:  Failed to initialize initial task.\n");
5630         tsec = current->security;
5631         tsec->osid = tsec->sid = SECINITSID_KERNEL;
5632
5633         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5634                                             sizeof(struct inode_security_struct),
5635                                             0, SLAB_PANIC, NULL);
5636         avc_init();
5637
5638         secondary_ops = security_ops;
5639         if (!secondary_ops)
5640                 panic("SELinux: No initial security operations\n");
5641         if (register_security(&selinux_ops))
5642                 panic("SELinux: Unable to register with kernel.\n");
5643
5644         if (selinux_enforcing)
5645                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5646         else
5647                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5648
5649         return 0;
5650 }
5651
5652 void selinux_complete_init(void)
5653 {
5654         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5655
5656         /* Set up any superblocks initialized prior to the policy load. */
5657         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5658         spin_lock(&sb_lock);
5659         spin_lock(&sb_security_lock);
5660 next_sb:
5661         if (!list_empty(&superblock_security_head)) {
5662                 struct superblock_security_struct *sbsec =
5663                                 list_entry(superblock_security_head.next,
5664                                            struct superblock_security_struct,
5665                                            list);
5666                 struct super_block *sb = sbsec->sb;
5667                 sb->s_count++;
5668                 spin_unlock(&sb_security_lock);
5669                 spin_unlock(&sb_lock);
5670                 down_read(&sb->s_umount);
5671                 if (sb->s_root)
5672                         superblock_doinit(sb, NULL);
5673                 drop_super(sb);
5674                 spin_lock(&sb_lock);
5675                 spin_lock(&sb_security_lock);
5676                 list_del_init(&sbsec->list);
5677                 goto next_sb;
5678         }
5679         spin_unlock(&sb_security_lock);
5680         spin_unlock(&sb_lock);
5681 }
5682
5683 /* SELinux requires early initialization in order to label
5684    all processes and objects when they are created. */
5685 security_initcall(selinux_init);
5686
5687 #if defined(CONFIG_NETFILTER)
5688
5689 static struct nf_hook_ops selinux_ipv4_ops[] = {
5690         {
5691                 .hook =         selinux_ipv4_postroute,
5692                 .owner =        THIS_MODULE,
5693                 .pf =           PF_INET,
5694                 .hooknum =      NF_INET_POST_ROUTING,
5695                 .priority =     NF_IP_PRI_SELINUX_LAST,
5696         },
5697         {
5698                 .hook =         selinux_ipv4_forward,
5699                 .owner =        THIS_MODULE,
5700                 .pf =           PF_INET,
5701                 .hooknum =      NF_INET_FORWARD,
5702                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5703         }
5704 };
5705
5706 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5707
5708 static struct nf_hook_ops selinux_ipv6_ops[] = {
5709         {
5710                 .hook =         selinux_ipv6_postroute,
5711                 .owner =        THIS_MODULE,
5712                 .pf =           PF_INET6,
5713                 .hooknum =      NF_INET_POST_ROUTING,
5714                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5715         },
5716         {
5717                 .hook =         selinux_ipv6_forward,
5718                 .owner =        THIS_MODULE,
5719                 .pf =           PF_INET6,
5720                 .hooknum =      NF_INET_FORWARD,
5721                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5722         }
5723 };
5724
5725 #endif  /* IPV6 */
5726
5727 static int __init selinux_nf_ip_init(void)
5728 {
5729         int err = 0;
5730
5731         if (!selinux_enabled)
5732                 goto out;
5733
5734         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5735
5736         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5737         if (err)
5738                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5739
5740 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5741         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5742         if (err)
5743                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5744 #endif  /* IPV6 */
5745
5746 out:
5747         return err;
5748 }
5749
5750 __initcall(selinux_nf_ip_init);
5751
5752 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5753 static void selinux_nf_ip_exit(void)
5754 {
5755         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5756
5757         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5758 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5759         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5760 #endif  /* IPV6 */
5761 }
5762 #endif
5763
5764 #else /* CONFIG_NETFILTER */
5765
5766 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5767 #define selinux_nf_ip_exit()
5768 #endif
5769
5770 #endif /* CONFIG_NETFILTER */
5771
5772 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5773 static int selinux_disabled;
5774
5775 int selinux_disable(void)
5776 {
5777         extern void exit_sel_fs(void);
5778
5779         if (ss_initialized) {
5780                 /* Not permitted after initial policy load. */
5781                 return -EINVAL;
5782         }
5783
5784         if (selinux_disabled) {
5785                 /* Only do this once. */
5786                 return -EINVAL;
5787         }
5788
5789         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5790
5791         selinux_disabled = 1;
5792         selinux_enabled = 0;
5793
5794         /* Reset security_ops to the secondary module, dummy or capability. */
5795         security_ops = secondary_ops;
5796
5797         /* Unregister netfilter hooks. */
5798         selinux_nf_ip_exit();
5799
5800         /* Unregister selinuxfs. */
5801         exit_sel_fs();
5802
5803         return 0;
5804 }
5805 #endif