userns: allow ptrace from non-init user namespaces
[linux-2.6.git] / security / selinux / hooks.c
1 /*
2  *  NSA Security-Enhanced Linux (SELinux) security module
3  *
4  *  This file contains the SELinux hook function implementations.
5  *
6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
7  *            Chris Vance, <cvance@nai.com>
8  *            Wayne Salamon, <wsalamon@nai.com>
9  *            James Morris <jmorris@redhat.com>
10  *
11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *                                         Eric Paris <eparis@redhat.com>
14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15  *                          <dgoeddel@trustedcs.com>
16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17  *      Paul Moore <paul.moore@hp.com>
18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
20  *
21  *      This program is free software; you can redistribute it and/or modify
22  *      it under the terms of the GNU General Public License version 2,
23  *      as published by the Free Software Foundation.
24  */
25
26 #include <linux/init.h>
27 #include <linux/kd.h>
28 #include <linux/kernel.h>
29 #include <linux/tracehook.h>
30 #include <linux/errno.h>
31 #include <linux/ext2_fs.h>
32 #include <linux/sched.h>
33 #include <linux/security.h>
34 #include <linux/xattr.h>
35 #include <linux/capability.h>
36 #include <linux/unistd.h>
37 #include <linux/mm.h>
38 #include <linux/mman.h>
39 #include <linux/slab.h>
40 #include <linux/pagemap.h>
41 #include <linux/proc_fs.h>
42 #include <linux/swap.h>
43 #include <linux/spinlock.h>
44 #include <linux/syscalls.h>
45 #include <linux/dcache.h>
46 #include <linux/file.h>
47 #include <linux/fdtable.h>
48 #include <linux/namei.h>
49 #include <linux/mount.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h>             /* for local_port_range[] */
55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
56 #include <net/net_namespace.h>
57 #include <net/netlabel.h>
58 #include <linux/uaccess.h>
59 #include <asm/ioctls.h>
60 #include <asm/atomic.h>
61 #include <linux/bitops.h>
62 #include <linux/interrupt.h>
63 #include <linux/netdevice.h>    /* for network interface checks */
64 #include <linux/netlink.h>
65 #include <linux/tcp.h>
66 #include <linux/udp.h>
67 #include <linux/dccp.h>
68 #include <linux/quota.h>
69 #include <linux/un.h>           /* for Unix socket types */
70 #include <net/af_unix.h>        /* for Unix socket types */
71 #include <linux/parser.h>
72 #include <linux/nfs_mount.h>
73 #include <net/ipv6.h>
74 #include <linux/hugetlb.h>
75 #include <linux/personality.h>
76 #include <linux/audit.h>
77 #include <linux/string.h>
78 #include <linux/selinux.h>
79 #include <linux/mutex.h>
80 #include <linux/posix-timers.h>
81 #include <linux/syslog.h>
82 #include <linux/user_namespace.h>
83
84 #include "avc.h"
85 #include "objsec.h"
86 #include "netif.h"
87 #include "netnode.h"
88 #include "netport.h"
89 #include "xfrm.h"
90 #include "netlabel.h"
91 #include "audit.h"
92
93 #define NUM_SEL_MNT_OPTS 5
94
95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96 extern struct security_operations *security_ops;
97
98 /* SECMARK reference count */
99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 int selinux_enforcing;
103
104 static int __init enforcing_setup(char *str)
105 {
106         unsigned long enforcing;
107         if (!strict_strtoul(str, 0, &enforcing))
108                 selinux_enforcing = enforcing ? 1 : 0;
109         return 1;
110 }
111 __setup("enforcing=", enforcing_setup);
112 #endif
113
114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117 static int __init selinux_enabled_setup(char *str)
118 {
119         unsigned long enabled;
120         if (!strict_strtoul(str, 0, &enabled))
121                 selinux_enabled = enabled ? 1 : 0;
122         return 1;
123 }
124 __setup("selinux=", selinux_enabled_setup);
125 #else
126 int selinux_enabled = 1;
127 #endif
128
129 static struct kmem_cache *sel_inode_cache;
130
131 /**
132  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133  *
134  * Description:
135  * This function checks the SECMARK reference counter to see if any SECMARK
136  * targets are currently configured, if the reference counter is greater than
137  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
138  * enabled, false (0) if SECMARK is disabled.
139  *
140  */
141 static int selinux_secmark_enabled(void)
142 {
143         return (atomic_read(&selinux_secmark_refcount) > 0);
144 }
145
146 /*
147  * initialise the security for the init task
148  */
149 static void cred_init_security(void)
150 {
151         struct cred *cred = (struct cred *) current->real_cred;
152         struct task_security_struct *tsec;
153
154         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
155         if (!tsec)
156                 panic("SELinux:  Failed to initialize initial task.\n");
157
158         tsec->osid = tsec->sid = SECINITSID_KERNEL;
159         cred->security = tsec;
160 }
161
162 /*
163  * get the security ID of a set of credentials
164  */
165 static inline u32 cred_sid(const struct cred *cred)
166 {
167         const struct task_security_struct *tsec;
168
169         tsec = cred->security;
170         return tsec->sid;
171 }
172
173 /*
174  * get the objective security ID of a task
175  */
176 static inline u32 task_sid(const struct task_struct *task)
177 {
178         u32 sid;
179
180         rcu_read_lock();
181         sid = cred_sid(__task_cred(task));
182         rcu_read_unlock();
183         return sid;
184 }
185
186 /*
187  * get the subjective security ID of the current task
188  */
189 static inline u32 current_sid(void)
190 {
191         const struct task_security_struct *tsec = current_security();
192
193         return tsec->sid;
194 }
195
196 /* Allocate and free functions for each kind of security blob. */
197
198 static int inode_alloc_security(struct inode *inode)
199 {
200         struct inode_security_struct *isec;
201         u32 sid = current_sid();
202
203         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
204         if (!isec)
205                 return -ENOMEM;
206
207         mutex_init(&isec->lock);
208         INIT_LIST_HEAD(&isec->list);
209         isec->inode = inode;
210         isec->sid = SECINITSID_UNLABELED;
211         isec->sclass = SECCLASS_FILE;
212         isec->task_sid = sid;
213         inode->i_security = isec;
214
215         return 0;
216 }
217
218 static void inode_free_security(struct inode *inode)
219 {
220         struct inode_security_struct *isec = inode->i_security;
221         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
222
223         spin_lock(&sbsec->isec_lock);
224         if (!list_empty(&isec->list))
225                 list_del_init(&isec->list);
226         spin_unlock(&sbsec->isec_lock);
227
228         inode->i_security = NULL;
229         kmem_cache_free(sel_inode_cache, isec);
230 }
231
232 static int file_alloc_security(struct file *file)
233 {
234         struct file_security_struct *fsec;
235         u32 sid = current_sid();
236
237         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
238         if (!fsec)
239                 return -ENOMEM;
240
241         fsec->sid = sid;
242         fsec->fown_sid = sid;
243         file->f_security = fsec;
244
245         return 0;
246 }
247
248 static void file_free_security(struct file *file)
249 {
250         struct file_security_struct *fsec = file->f_security;
251         file->f_security = NULL;
252         kfree(fsec);
253 }
254
255 static int superblock_alloc_security(struct super_block *sb)
256 {
257         struct superblock_security_struct *sbsec;
258
259         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
260         if (!sbsec)
261                 return -ENOMEM;
262
263         mutex_init(&sbsec->lock);
264         INIT_LIST_HEAD(&sbsec->isec_head);
265         spin_lock_init(&sbsec->isec_lock);
266         sbsec->sb = sb;
267         sbsec->sid = SECINITSID_UNLABELED;
268         sbsec->def_sid = SECINITSID_FILE;
269         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
270         sb->s_security = sbsec;
271
272         return 0;
273 }
274
275 static void superblock_free_security(struct super_block *sb)
276 {
277         struct superblock_security_struct *sbsec = sb->s_security;
278         sb->s_security = NULL;
279         kfree(sbsec);
280 }
281
282 /* The security server must be initialized before
283    any labeling or access decisions can be provided. */
284 extern int ss_initialized;
285
286 /* The file system's label must be initialized prior to use. */
287
288 static const char *labeling_behaviors[6] = {
289         "uses xattr",
290         "uses transition SIDs",
291         "uses task SIDs",
292         "uses genfs_contexts",
293         "not configured for labeling",
294         "uses mountpoint labeling",
295 };
296
297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
298
299 static inline int inode_doinit(struct inode *inode)
300 {
301         return inode_doinit_with_dentry(inode, NULL);
302 }
303
304 enum {
305         Opt_error = -1,
306         Opt_context = 1,
307         Opt_fscontext = 2,
308         Opt_defcontext = 3,
309         Opt_rootcontext = 4,
310         Opt_labelsupport = 5,
311 };
312
313 static const match_table_t tokens = {
314         {Opt_context, CONTEXT_STR "%s"},
315         {Opt_fscontext, FSCONTEXT_STR "%s"},
316         {Opt_defcontext, DEFCONTEXT_STR "%s"},
317         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
318         {Opt_labelsupport, LABELSUPP_STR},
319         {Opt_error, NULL},
320 };
321
322 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
323
324 static int may_context_mount_sb_relabel(u32 sid,
325                         struct superblock_security_struct *sbsec,
326                         const struct cred *cred)
327 {
328         const struct task_security_struct *tsec = cred->security;
329         int rc;
330
331         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
332                           FILESYSTEM__RELABELFROM, NULL);
333         if (rc)
334                 return rc;
335
336         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
337                           FILESYSTEM__RELABELTO, NULL);
338         return rc;
339 }
340
341 static int may_context_mount_inode_relabel(u32 sid,
342                         struct superblock_security_struct *sbsec,
343                         const struct cred *cred)
344 {
345         const struct task_security_struct *tsec = cred->security;
346         int rc;
347         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
348                           FILESYSTEM__RELABELFROM, NULL);
349         if (rc)
350                 return rc;
351
352         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
353                           FILESYSTEM__ASSOCIATE, NULL);
354         return rc;
355 }
356
357 static int sb_finish_set_opts(struct super_block *sb)
358 {
359         struct superblock_security_struct *sbsec = sb->s_security;
360         struct dentry *root = sb->s_root;
361         struct inode *root_inode = root->d_inode;
362         int rc = 0;
363
364         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
365                 /* Make sure that the xattr handler exists and that no
366                    error other than -ENODATA is returned by getxattr on
367                    the root directory.  -ENODATA is ok, as this may be
368                    the first boot of the SELinux kernel before we have
369                    assigned xattr values to the filesystem. */
370                 if (!root_inode->i_op->getxattr) {
371                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
372                                "xattr support\n", sb->s_id, sb->s_type->name);
373                         rc = -EOPNOTSUPP;
374                         goto out;
375                 }
376                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
377                 if (rc < 0 && rc != -ENODATA) {
378                         if (rc == -EOPNOTSUPP)
379                                 printk(KERN_WARNING "SELinux: (dev %s, type "
380                                        "%s) has no security xattr handler\n",
381                                        sb->s_id, sb->s_type->name);
382                         else
383                                 printk(KERN_WARNING "SELinux: (dev %s, type "
384                                        "%s) getxattr errno %d\n", sb->s_id,
385                                        sb->s_type->name, -rc);
386                         goto out;
387                 }
388         }
389
390         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
391
392         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
393                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
394                        sb->s_id, sb->s_type->name);
395         else
396                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
397                        sb->s_id, sb->s_type->name,
398                        labeling_behaviors[sbsec->behavior-1]);
399
400         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
401             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
402             sbsec->behavior == SECURITY_FS_USE_NONE ||
403             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404                 sbsec->flags &= ~SE_SBLABELSUPP;
405
406         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
407         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
408                 sbsec->flags |= SE_SBLABELSUPP;
409
410         /* Initialize the root inode. */
411         rc = inode_doinit_with_dentry(root_inode, root);
412
413         /* Initialize any other inodes associated with the superblock, e.g.
414            inodes created prior to initial policy load or inodes created
415            during get_sb by a pseudo filesystem that directly
416            populates itself. */
417         spin_lock(&sbsec->isec_lock);
418 next_inode:
419         if (!list_empty(&sbsec->isec_head)) {
420                 struct inode_security_struct *isec =
421                                 list_entry(sbsec->isec_head.next,
422                                            struct inode_security_struct, list);
423                 struct inode *inode = isec->inode;
424                 spin_unlock(&sbsec->isec_lock);
425                 inode = igrab(inode);
426                 if (inode) {
427                         if (!IS_PRIVATE(inode))
428                                 inode_doinit(inode);
429                         iput(inode);
430                 }
431                 spin_lock(&sbsec->isec_lock);
432                 list_del_init(&isec->list);
433                 goto next_inode;
434         }
435         spin_unlock(&sbsec->isec_lock);
436 out:
437         return rc;
438 }
439
440 /*
441  * This function should allow an FS to ask what it's mount security
442  * options were so it can use those later for submounts, displaying
443  * mount options, or whatever.
444  */
445 static int selinux_get_mnt_opts(const struct super_block *sb,
446                                 struct security_mnt_opts *opts)
447 {
448         int rc = 0, i;
449         struct superblock_security_struct *sbsec = sb->s_security;
450         char *context = NULL;
451         u32 len;
452         char tmp;
453
454         security_init_mnt_opts(opts);
455
456         if (!(sbsec->flags & SE_SBINITIALIZED))
457                 return -EINVAL;
458
459         if (!ss_initialized)
460                 return -EINVAL;
461
462         tmp = sbsec->flags & SE_MNTMASK;
463         /* count the number of mount options for this sb */
464         for (i = 0; i < 8; i++) {
465                 if (tmp & 0x01)
466                         opts->num_mnt_opts++;
467                 tmp >>= 1;
468         }
469         /* Check if the Label support flag is set */
470         if (sbsec->flags & SE_SBLABELSUPP)
471                 opts->num_mnt_opts++;
472
473         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
474         if (!opts->mnt_opts) {
475                 rc = -ENOMEM;
476                 goto out_free;
477         }
478
479         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
480         if (!opts->mnt_opts_flags) {
481                 rc = -ENOMEM;
482                 goto out_free;
483         }
484
485         i = 0;
486         if (sbsec->flags & FSCONTEXT_MNT) {
487                 rc = security_sid_to_context(sbsec->sid, &context, &len);
488                 if (rc)
489                         goto out_free;
490                 opts->mnt_opts[i] = context;
491                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
492         }
493         if (sbsec->flags & CONTEXT_MNT) {
494                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
495                 if (rc)
496                         goto out_free;
497                 opts->mnt_opts[i] = context;
498                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
499         }
500         if (sbsec->flags & DEFCONTEXT_MNT) {
501                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
502                 if (rc)
503                         goto out_free;
504                 opts->mnt_opts[i] = context;
505                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
506         }
507         if (sbsec->flags & ROOTCONTEXT_MNT) {
508                 struct inode *root = sbsec->sb->s_root->d_inode;
509                 struct inode_security_struct *isec = root->i_security;
510
511                 rc = security_sid_to_context(isec->sid, &context, &len);
512                 if (rc)
513                         goto out_free;
514                 opts->mnt_opts[i] = context;
515                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
516         }
517         if (sbsec->flags & SE_SBLABELSUPP) {
518                 opts->mnt_opts[i] = NULL;
519                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
520         }
521
522         BUG_ON(i != opts->num_mnt_opts);
523
524         return 0;
525
526 out_free:
527         security_free_mnt_opts(opts);
528         return rc;
529 }
530
531 static int bad_option(struct superblock_security_struct *sbsec, char flag,
532                       u32 old_sid, u32 new_sid)
533 {
534         char mnt_flags = sbsec->flags & SE_MNTMASK;
535
536         /* check if the old mount command had the same options */
537         if (sbsec->flags & SE_SBINITIALIZED)
538                 if (!(sbsec->flags & flag) ||
539                     (old_sid != new_sid))
540                         return 1;
541
542         /* check if we were passed the same options twice,
543          * aka someone passed context=a,context=b
544          */
545         if (!(sbsec->flags & SE_SBINITIALIZED))
546                 if (mnt_flags & flag)
547                         return 1;
548         return 0;
549 }
550
551 /*
552  * Allow filesystems with binary mount data to explicitly set mount point
553  * labeling information.
554  */
555 static int selinux_set_mnt_opts(struct super_block *sb,
556                                 struct security_mnt_opts *opts)
557 {
558         const struct cred *cred = current_cred();
559         int rc = 0, i;
560         struct superblock_security_struct *sbsec = sb->s_security;
561         const char *name = sb->s_type->name;
562         struct inode *inode = sbsec->sb->s_root->d_inode;
563         struct inode_security_struct *root_isec = inode->i_security;
564         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
565         u32 defcontext_sid = 0;
566         char **mount_options = opts->mnt_opts;
567         int *flags = opts->mnt_opts_flags;
568         int num_opts = opts->num_mnt_opts;
569
570         mutex_lock(&sbsec->lock);
571
572         if (!ss_initialized) {
573                 if (!num_opts) {
574                         /* Defer initialization until selinux_complete_init,
575                            after the initial policy is loaded and the security
576                            server is ready to handle calls. */
577                         goto out;
578                 }
579                 rc = -EINVAL;
580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581                         "before the security server is initialized\n");
582                 goto out;
583         }
584
585         /*
586          * Binary mount data FS will come through this function twice.  Once
587          * from an explicit call and once from the generic calls from the vfs.
588          * Since the generic VFS calls will not contain any security mount data
589          * we need to skip the double mount verification.
590          *
591          * This does open a hole in which we will not notice if the first
592          * mount using this sb set explict options and a second mount using
593          * this sb does not set any security options.  (The first options
594          * will be used for both mounts)
595          */
596         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597             && (num_opts == 0))
598                 goto out;
599
600         /*
601          * parse the mount options, check if they are valid sids.
602          * also check if someone is trying to mount the same sb more
603          * than once with different security options.
604          */
605         for (i = 0; i < num_opts; i++) {
606                 u32 sid;
607
608                 if (flags[i] == SE_SBLABELSUPP)
609                         continue;
610                 rc = security_context_to_sid(mount_options[i],
611                                              strlen(mount_options[i]), &sid);
612                 if (rc) {
613                         printk(KERN_WARNING "SELinux: security_context_to_sid"
614                                "(%s) failed for (dev %s, type %s) errno=%d\n",
615                                mount_options[i], sb->s_id, name, rc);
616                         goto out;
617                 }
618                 switch (flags[i]) {
619                 case FSCONTEXT_MNT:
620                         fscontext_sid = sid;
621
622                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
623                                         fscontext_sid))
624                                 goto out_double_mount;
625
626                         sbsec->flags |= FSCONTEXT_MNT;
627                         break;
628                 case CONTEXT_MNT:
629                         context_sid = sid;
630
631                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
632                                         context_sid))
633                                 goto out_double_mount;
634
635                         sbsec->flags |= CONTEXT_MNT;
636                         break;
637                 case ROOTCONTEXT_MNT:
638                         rootcontext_sid = sid;
639
640                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
641                                         rootcontext_sid))
642                                 goto out_double_mount;
643
644                         sbsec->flags |= ROOTCONTEXT_MNT;
645
646                         break;
647                 case DEFCONTEXT_MNT:
648                         defcontext_sid = sid;
649
650                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
651                                         defcontext_sid))
652                                 goto out_double_mount;
653
654                         sbsec->flags |= DEFCONTEXT_MNT;
655
656                         break;
657                 default:
658                         rc = -EINVAL;
659                         goto out;
660                 }
661         }
662
663         if (sbsec->flags & SE_SBINITIALIZED) {
664                 /* previously mounted with options, but not on this attempt? */
665                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666                         goto out_double_mount;
667                 rc = 0;
668                 goto out;
669         }
670
671         if (strcmp(sb->s_type->name, "proc") == 0)
672                 sbsec->flags |= SE_SBPROC;
673
674         /* Determine the labeling behavior to use for this filesystem type. */
675         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676         if (rc) {
677                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678                        __func__, sb->s_type->name, rc);
679                 goto out;
680         }
681
682         /* sets the context of the superblock for the fs being mounted. */
683         if (fscontext_sid) {
684                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
685                 if (rc)
686                         goto out;
687
688                 sbsec->sid = fscontext_sid;
689         }
690
691         /*
692          * Switch to using mount point labeling behavior.
693          * sets the label used on all file below the mountpoint, and will set
694          * the superblock context if not already set.
695          */
696         if (context_sid) {
697                 if (!fscontext_sid) {
698                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
699                                                           cred);
700                         if (rc)
701                                 goto out;
702                         sbsec->sid = context_sid;
703                 } else {
704                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
705                                                              cred);
706                         if (rc)
707                                 goto out;
708                 }
709                 if (!rootcontext_sid)
710                         rootcontext_sid = context_sid;
711
712                 sbsec->mntpoint_sid = context_sid;
713                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
714         }
715
716         if (rootcontext_sid) {
717                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
718                                                      cred);
719                 if (rc)
720                         goto out;
721
722                 root_isec->sid = rootcontext_sid;
723                 root_isec->initialized = 1;
724         }
725
726         if (defcontext_sid) {
727                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
728                         rc = -EINVAL;
729                         printk(KERN_WARNING "SELinux: defcontext option is "
730                                "invalid for this filesystem type\n");
731                         goto out;
732                 }
733
734                 if (defcontext_sid != sbsec->def_sid) {
735                         rc = may_context_mount_inode_relabel(defcontext_sid,
736                                                              sbsec, cred);
737                         if (rc)
738                                 goto out;
739                 }
740
741                 sbsec->def_sid = defcontext_sid;
742         }
743
744         rc = sb_finish_set_opts(sb);
745 out:
746         mutex_unlock(&sbsec->lock);
747         return rc;
748 out_double_mount:
749         rc = -EINVAL;
750         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
751                "security settings for (dev %s, type %s)\n", sb->s_id, name);
752         goto out;
753 }
754
755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
756                                         struct super_block *newsb)
757 {
758         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
759         struct superblock_security_struct *newsbsec = newsb->s_security;
760
761         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
762         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
763         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
764
765         /*
766          * if the parent was able to be mounted it clearly had no special lsm
767          * mount options.  thus we can safely deal with this superblock later
768          */
769         if (!ss_initialized)
770                 return;
771
772         /* how can we clone if the old one wasn't set up?? */
773         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774
775         /* if fs is reusing a sb, just let its options stand... */
776         if (newsbsec->flags & SE_SBINITIALIZED)
777                 return;
778
779         mutex_lock(&newsbsec->lock);
780
781         newsbsec->flags = oldsbsec->flags;
782
783         newsbsec->sid = oldsbsec->sid;
784         newsbsec->def_sid = oldsbsec->def_sid;
785         newsbsec->behavior = oldsbsec->behavior;
786
787         if (set_context) {
788                 u32 sid = oldsbsec->mntpoint_sid;
789
790                 if (!set_fscontext)
791                         newsbsec->sid = sid;
792                 if (!set_rootcontext) {
793                         struct inode *newinode = newsb->s_root->d_inode;
794                         struct inode_security_struct *newisec = newinode->i_security;
795                         newisec->sid = sid;
796                 }
797                 newsbsec->mntpoint_sid = sid;
798         }
799         if (set_rootcontext) {
800                 const struct inode *oldinode = oldsb->s_root->d_inode;
801                 const struct inode_security_struct *oldisec = oldinode->i_security;
802                 struct inode *newinode = newsb->s_root->d_inode;
803                 struct inode_security_struct *newisec = newinode->i_security;
804
805                 newisec->sid = oldisec->sid;
806         }
807
808         sb_finish_set_opts(newsb);
809         mutex_unlock(&newsbsec->lock);
810 }
811
812 static int selinux_parse_opts_str(char *options,
813                                   struct security_mnt_opts *opts)
814 {
815         char *p;
816         char *context = NULL, *defcontext = NULL;
817         char *fscontext = NULL, *rootcontext = NULL;
818         int rc, num_mnt_opts = 0;
819
820         opts->num_mnt_opts = 0;
821
822         /* Standard string-based options. */
823         while ((p = strsep(&options, "|")) != NULL) {
824                 int token;
825                 substring_t args[MAX_OPT_ARGS];
826
827                 if (!*p)
828                         continue;
829
830                 token = match_token(p, tokens, args);
831
832                 switch (token) {
833                 case Opt_context:
834                         if (context || defcontext) {
835                                 rc = -EINVAL;
836                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
837                                 goto out_err;
838                         }
839                         context = match_strdup(&args[0]);
840                         if (!context) {
841                                 rc = -ENOMEM;
842                                 goto out_err;
843                         }
844                         break;
845
846                 case Opt_fscontext:
847                         if (fscontext) {
848                                 rc = -EINVAL;
849                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
850                                 goto out_err;
851                         }
852                         fscontext = match_strdup(&args[0]);
853                         if (!fscontext) {
854                                 rc = -ENOMEM;
855                                 goto out_err;
856                         }
857                         break;
858
859                 case Opt_rootcontext:
860                         if (rootcontext) {
861                                 rc = -EINVAL;
862                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
863                                 goto out_err;
864                         }
865                         rootcontext = match_strdup(&args[0]);
866                         if (!rootcontext) {
867                                 rc = -ENOMEM;
868                                 goto out_err;
869                         }
870                         break;
871
872                 case Opt_defcontext:
873                         if (context || defcontext) {
874                                 rc = -EINVAL;
875                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
876                                 goto out_err;
877                         }
878                         defcontext = match_strdup(&args[0]);
879                         if (!defcontext) {
880                                 rc = -ENOMEM;
881                                 goto out_err;
882                         }
883                         break;
884                 case Opt_labelsupport:
885                         break;
886                 default:
887                         rc = -EINVAL;
888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
889                         goto out_err;
890
891                 }
892         }
893
894         rc = -ENOMEM;
895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896         if (!opts->mnt_opts)
897                 goto out_err;
898
899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900         if (!opts->mnt_opts_flags) {
901                 kfree(opts->mnt_opts);
902                 goto out_err;
903         }
904
905         if (fscontext) {
906                 opts->mnt_opts[num_mnt_opts] = fscontext;
907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908         }
909         if (context) {
910                 opts->mnt_opts[num_mnt_opts] = context;
911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912         }
913         if (rootcontext) {
914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916         }
917         if (defcontext) {
918                 opts->mnt_opts[num_mnt_opts] = defcontext;
919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920         }
921
922         opts->num_mnt_opts = num_mnt_opts;
923         return 0;
924
925 out_err:
926         kfree(context);
927         kfree(defcontext);
928         kfree(fscontext);
929         kfree(rootcontext);
930         return rc;
931 }
932 /*
933  * string mount options parsing and call set the sbsec
934  */
935 static int superblock_doinit(struct super_block *sb, void *data)
936 {
937         int rc = 0;
938         char *options = data;
939         struct security_mnt_opts opts;
940
941         security_init_mnt_opts(&opts);
942
943         if (!data)
944                 goto out;
945
946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948         rc = selinux_parse_opts_str(options, &opts);
949         if (rc)
950                 goto out_err;
951
952 out:
953         rc = selinux_set_mnt_opts(sb, &opts);
954
955 out_err:
956         security_free_mnt_opts(&opts);
957         return rc;
958 }
959
960 static void selinux_write_opts(struct seq_file *m,
961                                struct security_mnt_opts *opts)
962 {
963         int i;
964         char *prefix;
965
966         for (i = 0; i < opts->num_mnt_opts; i++) {
967                 char *has_comma;
968
969                 if (opts->mnt_opts[i])
970                         has_comma = strchr(opts->mnt_opts[i], ',');
971                 else
972                         has_comma = NULL;
973
974                 switch (opts->mnt_opts_flags[i]) {
975                 case CONTEXT_MNT:
976                         prefix = CONTEXT_STR;
977                         break;
978                 case FSCONTEXT_MNT:
979                         prefix = FSCONTEXT_STR;
980                         break;
981                 case ROOTCONTEXT_MNT:
982                         prefix = ROOTCONTEXT_STR;
983                         break;
984                 case DEFCONTEXT_MNT:
985                         prefix = DEFCONTEXT_STR;
986                         break;
987                 case SE_SBLABELSUPP:
988                         seq_putc(m, ',');
989                         seq_puts(m, LABELSUPP_STR);
990                         continue;
991                 default:
992                         BUG();
993                 };
994                 /* we need a comma before each option */
995                 seq_putc(m, ',');
996                 seq_puts(m, prefix);
997                 if (has_comma)
998                         seq_putc(m, '\"');
999                 seq_puts(m, opts->mnt_opts[i]);
1000                 if (has_comma)
1001                         seq_putc(m, '\"');
1002         }
1003 }
1004
1005 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1006 {
1007         struct security_mnt_opts opts;
1008         int rc;
1009
1010         rc = selinux_get_mnt_opts(sb, &opts);
1011         if (rc) {
1012                 /* before policy load we may get EINVAL, don't show anything */
1013                 if (rc == -EINVAL)
1014                         rc = 0;
1015                 return rc;
1016         }
1017
1018         selinux_write_opts(m, &opts);
1019
1020         security_free_mnt_opts(&opts);
1021
1022         return rc;
1023 }
1024
1025 static inline u16 inode_mode_to_security_class(umode_t mode)
1026 {
1027         switch (mode & S_IFMT) {
1028         case S_IFSOCK:
1029                 return SECCLASS_SOCK_FILE;
1030         case S_IFLNK:
1031                 return SECCLASS_LNK_FILE;
1032         case S_IFREG:
1033                 return SECCLASS_FILE;
1034         case S_IFBLK:
1035                 return SECCLASS_BLK_FILE;
1036         case S_IFDIR:
1037                 return SECCLASS_DIR;
1038         case S_IFCHR:
1039                 return SECCLASS_CHR_FILE;
1040         case S_IFIFO:
1041                 return SECCLASS_FIFO_FILE;
1042
1043         }
1044
1045         return SECCLASS_FILE;
1046 }
1047
1048 static inline int default_protocol_stream(int protocol)
1049 {
1050         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1051 }
1052
1053 static inline int default_protocol_dgram(int protocol)
1054 {
1055         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1056 }
1057
1058 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1059 {
1060         switch (family) {
1061         case PF_UNIX:
1062                 switch (type) {
1063                 case SOCK_STREAM:
1064                 case SOCK_SEQPACKET:
1065                         return SECCLASS_UNIX_STREAM_SOCKET;
1066                 case SOCK_DGRAM:
1067                         return SECCLASS_UNIX_DGRAM_SOCKET;
1068                 }
1069                 break;
1070         case PF_INET:
1071         case PF_INET6:
1072                 switch (type) {
1073                 case SOCK_STREAM:
1074                         if (default_protocol_stream(protocol))
1075                                 return SECCLASS_TCP_SOCKET;
1076                         else
1077                                 return SECCLASS_RAWIP_SOCKET;
1078                 case SOCK_DGRAM:
1079                         if (default_protocol_dgram(protocol))
1080                                 return SECCLASS_UDP_SOCKET;
1081                         else
1082                                 return SECCLASS_RAWIP_SOCKET;
1083                 case SOCK_DCCP:
1084                         return SECCLASS_DCCP_SOCKET;
1085                 default:
1086                         return SECCLASS_RAWIP_SOCKET;
1087                 }
1088                 break;
1089         case PF_NETLINK:
1090                 switch (protocol) {
1091                 case NETLINK_ROUTE:
1092                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1093                 case NETLINK_FIREWALL:
1094                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1095                 case NETLINK_INET_DIAG:
1096                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1097                 case NETLINK_NFLOG:
1098                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1099                 case NETLINK_XFRM:
1100                         return SECCLASS_NETLINK_XFRM_SOCKET;
1101                 case NETLINK_SELINUX:
1102                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1103                 case NETLINK_AUDIT:
1104                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1105                 case NETLINK_IP6_FW:
1106                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1107                 case NETLINK_DNRTMSG:
1108                         return SECCLASS_NETLINK_DNRT_SOCKET;
1109                 case NETLINK_KOBJECT_UEVENT:
1110                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1111                 default:
1112                         return SECCLASS_NETLINK_SOCKET;
1113                 }
1114         case PF_PACKET:
1115                 return SECCLASS_PACKET_SOCKET;
1116         case PF_KEY:
1117                 return SECCLASS_KEY_SOCKET;
1118         case PF_APPLETALK:
1119                 return SECCLASS_APPLETALK_SOCKET;
1120         }
1121
1122         return SECCLASS_SOCKET;
1123 }
1124
1125 #ifdef CONFIG_PROC_FS
1126 static int selinux_proc_get_sid(struct dentry *dentry,
1127                                 u16 tclass,
1128                                 u32 *sid)
1129 {
1130         int rc;
1131         char *buffer, *path;
1132
1133         buffer = (char *)__get_free_page(GFP_KERNEL);
1134         if (!buffer)
1135                 return -ENOMEM;
1136
1137         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1138         if (IS_ERR(path))
1139                 rc = PTR_ERR(path);
1140         else {
1141                 /* each process gets a /proc/PID/ entry. Strip off the
1142                  * PID part to get a valid selinux labeling.
1143                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1144                 while (path[1] >= '0' && path[1] <= '9') {
1145                         path[1] = '/';
1146                         path++;
1147                 }
1148                 rc = security_genfs_sid("proc", path, tclass, sid);
1149         }
1150         free_page((unsigned long)buffer);
1151         return rc;
1152 }
1153 #else
1154 static int selinux_proc_get_sid(struct dentry *dentry,
1155                                 u16 tclass,
1156                                 u32 *sid)
1157 {
1158         return -EINVAL;
1159 }
1160 #endif
1161
1162 /* The inode's security attributes must be initialized before first use. */
1163 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1164 {
1165         struct superblock_security_struct *sbsec = NULL;
1166         struct inode_security_struct *isec = inode->i_security;
1167         u32 sid;
1168         struct dentry *dentry;
1169 #define INITCONTEXTLEN 255
1170         char *context = NULL;
1171         unsigned len = 0;
1172         int rc = 0;
1173
1174         if (isec->initialized)
1175                 goto out;
1176
1177         mutex_lock(&isec->lock);
1178         if (isec->initialized)
1179                 goto out_unlock;
1180
1181         sbsec = inode->i_sb->s_security;
1182         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1183                 /* Defer initialization until selinux_complete_init,
1184                    after the initial policy is loaded and the security
1185                    server is ready to handle calls. */
1186                 spin_lock(&sbsec->isec_lock);
1187                 if (list_empty(&isec->list))
1188                         list_add(&isec->list, &sbsec->isec_head);
1189                 spin_unlock(&sbsec->isec_lock);
1190                 goto out_unlock;
1191         }
1192
1193         switch (sbsec->behavior) {
1194         case SECURITY_FS_USE_XATTR:
1195                 if (!inode->i_op->getxattr) {
1196                         isec->sid = sbsec->def_sid;
1197                         break;
1198                 }
1199
1200                 /* Need a dentry, since the xattr API requires one.
1201                    Life would be simpler if we could just pass the inode. */
1202                 if (opt_dentry) {
1203                         /* Called from d_instantiate or d_splice_alias. */
1204                         dentry = dget(opt_dentry);
1205                 } else {
1206                         /* Called from selinux_complete_init, try to find a dentry. */
1207                         dentry = d_find_alias(inode);
1208                 }
1209                 if (!dentry) {
1210                         /*
1211                          * this is can be hit on boot when a file is accessed
1212                          * before the policy is loaded.  When we load policy we
1213                          * may find inodes that have no dentry on the
1214                          * sbsec->isec_head list.  No reason to complain as these
1215                          * will get fixed up the next time we go through
1216                          * inode_doinit with a dentry, before these inodes could
1217                          * be used again by userspace.
1218                          */
1219                         goto out_unlock;
1220                 }
1221
1222                 len = INITCONTEXTLEN;
1223                 context = kmalloc(len+1, GFP_NOFS);
1224                 if (!context) {
1225                         rc = -ENOMEM;
1226                         dput(dentry);
1227                         goto out_unlock;
1228                 }
1229                 context[len] = '\0';
1230                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1231                                            context, len);
1232                 if (rc == -ERANGE) {
1233                         kfree(context);
1234
1235                         /* Need a larger buffer.  Query for the right size. */
1236                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1237                                                    NULL, 0);
1238                         if (rc < 0) {
1239                                 dput(dentry);
1240                                 goto out_unlock;
1241                         }
1242                         len = rc;
1243                         context = kmalloc(len+1, GFP_NOFS);
1244                         if (!context) {
1245                                 rc = -ENOMEM;
1246                                 dput(dentry);
1247                                 goto out_unlock;
1248                         }
1249                         context[len] = '\0';
1250                         rc = inode->i_op->getxattr(dentry,
1251                                                    XATTR_NAME_SELINUX,
1252                                                    context, len);
1253                 }
1254                 dput(dentry);
1255                 if (rc < 0) {
1256                         if (rc != -ENODATA) {
1257                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1258                                        "%d for dev=%s ino=%ld\n", __func__,
1259                                        -rc, inode->i_sb->s_id, inode->i_ino);
1260                                 kfree(context);
1261                                 goto out_unlock;
1262                         }
1263                         /* Map ENODATA to the default file SID */
1264                         sid = sbsec->def_sid;
1265                         rc = 0;
1266                 } else {
1267                         rc = security_context_to_sid_default(context, rc, &sid,
1268                                                              sbsec->def_sid,
1269                                                              GFP_NOFS);
1270                         if (rc) {
1271                                 char *dev = inode->i_sb->s_id;
1272                                 unsigned long ino = inode->i_ino;
1273
1274                                 if (rc == -EINVAL) {
1275                                         if (printk_ratelimit())
1276                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1277                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1278                                                         "filesystem in question.\n", ino, dev, context);
1279                                 } else {
1280                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1281                                                "returned %d for dev=%s ino=%ld\n",
1282                                                __func__, context, -rc, dev, ino);
1283                                 }
1284                                 kfree(context);
1285                                 /* Leave with the unlabeled SID */
1286                                 rc = 0;
1287                                 break;
1288                         }
1289                 }
1290                 kfree(context);
1291                 isec->sid = sid;
1292                 break;
1293         case SECURITY_FS_USE_TASK:
1294                 isec->sid = isec->task_sid;
1295                 break;
1296         case SECURITY_FS_USE_TRANS:
1297                 /* Default to the fs SID. */
1298                 isec->sid = sbsec->sid;
1299
1300                 /* Try to obtain a transition SID. */
1301                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1302                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1303                                              isec->sclass, NULL, &sid);
1304                 if (rc)
1305                         goto out_unlock;
1306                 isec->sid = sid;
1307                 break;
1308         case SECURITY_FS_USE_MNTPOINT:
1309                 isec->sid = sbsec->mntpoint_sid;
1310                 break;
1311         default:
1312                 /* Default to the fs superblock SID. */
1313                 isec->sid = sbsec->sid;
1314
1315                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1316                         if (opt_dentry) {
1317                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1318                                 rc = selinux_proc_get_sid(opt_dentry,
1319                                                           isec->sclass,
1320                                                           &sid);
1321                                 if (rc)
1322                                         goto out_unlock;
1323                                 isec->sid = sid;
1324                         }
1325                 }
1326                 break;
1327         }
1328
1329         isec->initialized = 1;
1330
1331 out_unlock:
1332         mutex_unlock(&isec->lock);
1333 out:
1334         if (isec->sclass == SECCLASS_FILE)
1335                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1336         return rc;
1337 }
1338
1339 /* Convert a Linux signal to an access vector. */
1340 static inline u32 signal_to_av(int sig)
1341 {
1342         u32 perm = 0;
1343
1344         switch (sig) {
1345         case SIGCHLD:
1346                 /* Commonly granted from child to parent. */
1347                 perm = PROCESS__SIGCHLD;
1348                 break;
1349         case SIGKILL:
1350                 /* Cannot be caught or ignored */
1351                 perm = PROCESS__SIGKILL;
1352                 break;
1353         case SIGSTOP:
1354                 /* Cannot be caught or ignored */
1355                 perm = PROCESS__SIGSTOP;
1356                 break;
1357         default:
1358                 /* All other signals. */
1359                 perm = PROCESS__SIGNAL;
1360                 break;
1361         }
1362
1363         return perm;
1364 }
1365
1366 /*
1367  * Check permission between a pair of credentials
1368  * fork check, ptrace check, etc.
1369  */
1370 static int cred_has_perm(const struct cred *actor,
1371                          const struct cred *target,
1372                          u32 perms)
1373 {
1374         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1375
1376         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1377 }
1378
1379 /*
1380  * Check permission between a pair of tasks, e.g. signal checks,
1381  * fork check, ptrace check, etc.
1382  * tsk1 is the actor and tsk2 is the target
1383  * - this uses the default subjective creds of tsk1
1384  */
1385 static int task_has_perm(const struct task_struct *tsk1,
1386                          const struct task_struct *tsk2,
1387                          u32 perms)
1388 {
1389         const struct task_security_struct *__tsec1, *__tsec2;
1390         u32 sid1, sid2;
1391
1392         rcu_read_lock();
1393         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1394         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1395         rcu_read_unlock();
1396         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1397 }
1398
1399 /*
1400  * Check permission between current and another task, e.g. signal checks,
1401  * fork check, ptrace check, etc.
1402  * current is the actor and tsk2 is the target
1403  * - this uses current's subjective creds
1404  */
1405 static int current_has_perm(const struct task_struct *tsk,
1406                             u32 perms)
1407 {
1408         u32 sid, tsid;
1409
1410         sid = current_sid();
1411         tsid = task_sid(tsk);
1412         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1413 }
1414
1415 #if CAP_LAST_CAP > 63
1416 #error Fix SELinux to handle capabilities > 63.
1417 #endif
1418
1419 /* Check whether a task is allowed to use a capability. */
1420 static int task_has_capability(struct task_struct *tsk,
1421                                const struct cred *cred,
1422                                int cap, int audit)
1423 {
1424         struct common_audit_data ad;
1425         struct av_decision avd;
1426         u16 sclass;
1427         u32 sid = cred_sid(cred);
1428         u32 av = CAP_TO_MASK(cap);
1429         int rc;
1430
1431         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1432         ad.tsk = tsk;
1433         ad.u.cap = cap;
1434
1435         switch (CAP_TO_INDEX(cap)) {
1436         case 0:
1437                 sclass = SECCLASS_CAPABILITY;
1438                 break;
1439         case 1:
1440                 sclass = SECCLASS_CAPABILITY2;
1441                 break;
1442         default:
1443                 printk(KERN_ERR
1444                        "SELinux:  out of range capability %d\n", cap);
1445                 BUG();
1446         }
1447
1448         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1449         if (audit == SECURITY_CAP_AUDIT)
1450                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1451         return rc;
1452 }
1453
1454 /* Check whether a task is allowed to use a system operation. */
1455 static int task_has_system(struct task_struct *tsk,
1456                            u32 perms)
1457 {
1458         u32 sid = task_sid(tsk);
1459
1460         return avc_has_perm(sid, SECINITSID_KERNEL,
1461                             SECCLASS_SYSTEM, perms, NULL);
1462 }
1463
1464 /* Check whether a task has a particular permission to an inode.
1465    The 'adp' parameter is optional and allows other audit
1466    data to be passed (e.g. the dentry). */
1467 static int inode_has_perm(const struct cred *cred,
1468                           struct inode *inode,
1469                           u32 perms,
1470                           struct common_audit_data *adp)
1471 {
1472         struct inode_security_struct *isec;
1473         struct common_audit_data ad;
1474         u32 sid;
1475
1476         validate_creds(cred);
1477
1478         if (unlikely(IS_PRIVATE(inode)))
1479                 return 0;
1480
1481         sid = cred_sid(cred);
1482         isec = inode->i_security;
1483
1484         if (!adp) {
1485                 adp = &ad;
1486                 COMMON_AUDIT_DATA_INIT(&ad, FS);
1487                 ad.u.fs.inode = inode;
1488         }
1489
1490         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1491 }
1492
1493 /* Same as inode_has_perm, but pass explicit audit data containing
1494    the dentry to help the auditing code to more easily generate the
1495    pathname if needed. */
1496 static inline int dentry_has_perm(const struct cred *cred,
1497                                   struct vfsmount *mnt,
1498                                   struct dentry *dentry,
1499                                   u32 av)
1500 {
1501         struct inode *inode = dentry->d_inode;
1502         struct common_audit_data ad;
1503
1504         COMMON_AUDIT_DATA_INIT(&ad, FS);
1505         ad.u.fs.path.mnt = mnt;
1506         ad.u.fs.path.dentry = dentry;
1507         return inode_has_perm(cred, inode, av, &ad);
1508 }
1509
1510 /* Check whether a task can use an open file descriptor to
1511    access an inode in a given way.  Check access to the
1512    descriptor itself, and then use dentry_has_perm to
1513    check a particular permission to the file.
1514    Access to the descriptor is implicitly granted if it
1515    has the same SID as the process.  If av is zero, then
1516    access to the file is not checked, e.g. for cases
1517    where only the descriptor is affected like seek. */
1518 static int file_has_perm(const struct cred *cred,
1519                          struct file *file,
1520                          u32 av)
1521 {
1522         struct file_security_struct *fsec = file->f_security;
1523         struct inode *inode = file->f_path.dentry->d_inode;
1524         struct common_audit_data ad;
1525         u32 sid = cred_sid(cred);
1526         int rc;
1527
1528         COMMON_AUDIT_DATA_INIT(&ad, FS);
1529         ad.u.fs.path = file->f_path;
1530
1531         if (sid != fsec->sid) {
1532                 rc = avc_has_perm(sid, fsec->sid,
1533                                   SECCLASS_FD,
1534                                   FD__USE,
1535                                   &ad);
1536                 if (rc)
1537                         goto out;
1538         }
1539
1540         /* av is zero if only checking access to the descriptor. */
1541         rc = 0;
1542         if (av)
1543                 rc = inode_has_perm(cred, inode, av, &ad);
1544
1545 out:
1546         return rc;
1547 }
1548
1549 /* Check whether a task can create a file. */
1550 static int may_create(struct inode *dir,
1551                       struct dentry *dentry,
1552                       u16 tclass)
1553 {
1554         const struct task_security_struct *tsec = current_security();
1555         struct inode_security_struct *dsec;
1556         struct superblock_security_struct *sbsec;
1557         u32 sid, newsid;
1558         struct common_audit_data ad;
1559         int rc;
1560
1561         dsec = dir->i_security;
1562         sbsec = dir->i_sb->s_security;
1563
1564         sid = tsec->sid;
1565         newsid = tsec->create_sid;
1566
1567         COMMON_AUDIT_DATA_INIT(&ad, FS);
1568         ad.u.fs.path.dentry = dentry;
1569
1570         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1571                           DIR__ADD_NAME | DIR__SEARCH,
1572                           &ad);
1573         if (rc)
1574                 return rc;
1575
1576         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1577                 rc = security_transition_sid(sid, dsec->sid, tclass, NULL, &newsid);
1578                 if (rc)
1579                         return rc;
1580         }
1581
1582         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1583         if (rc)
1584                 return rc;
1585
1586         return avc_has_perm(newsid, sbsec->sid,
1587                             SECCLASS_FILESYSTEM,
1588                             FILESYSTEM__ASSOCIATE, &ad);
1589 }
1590
1591 /* Check whether a task can create a key. */
1592 static int may_create_key(u32 ksid,
1593                           struct task_struct *ctx)
1594 {
1595         u32 sid = task_sid(ctx);
1596
1597         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1598 }
1599
1600 #define MAY_LINK        0
1601 #define MAY_UNLINK      1
1602 #define MAY_RMDIR       2
1603
1604 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1605 static int may_link(struct inode *dir,
1606                     struct dentry *dentry,
1607                     int kind)
1608
1609 {
1610         struct inode_security_struct *dsec, *isec;
1611         struct common_audit_data ad;
1612         u32 sid = current_sid();
1613         u32 av;
1614         int rc;
1615
1616         dsec = dir->i_security;
1617         isec = dentry->d_inode->i_security;
1618
1619         COMMON_AUDIT_DATA_INIT(&ad, FS);
1620         ad.u.fs.path.dentry = dentry;
1621
1622         av = DIR__SEARCH;
1623         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1624         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1625         if (rc)
1626                 return rc;
1627
1628         switch (kind) {
1629         case MAY_LINK:
1630                 av = FILE__LINK;
1631                 break;
1632         case MAY_UNLINK:
1633                 av = FILE__UNLINK;
1634                 break;
1635         case MAY_RMDIR:
1636                 av = DIR__RMDIR;
1637                 break;
1638         default:
1639                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1640                         __func__, kind);
1641                 return 0;
1642         }
1643
1644         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1645         return rc;
1646 }
1647
1648 static inline int may_rename(struct inode *old_dir,
1649                              struct dentry *old_dentry,
1650                              struct inode *new_dir,
1651                              struct dentry *new_dentry)
1652 {
1653         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1654         struct common_audit_data ad;
1655         u32 sid = current_sid();
1656         u32 av;
1657         int old_is_dir, new_is_dir;
1658         int rc;
1659
1660         old_dsec = old_dir->i_security;
1661         old_isec = old_dentry->d_inode->i_security;
1662         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1663         new_dsec = new_dir->i_security;
1664
1665         COMMON_AUDIT_DATA_INIT(&ad, FS);
1666
1667         ad.u.fs.path.dentry = old_dentry;
1668         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1669                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1670         if (rc)
1671                 return rc;
1672         rc = avc_has_perm(sid, old_isec->sid,
1673                           old_isec->sclass, FILE__RENAME, &ad);
1674         if (rc)
1675                 return rc;
1676         if (old_is_dir && new_dir != old_dir) {
1677                 rc = avc_has_perm(sid, old_isec->sid,
1678                                   old_isec->sclass, DIR__REPARENT, &ad);
1679                 if (rc)
1680                         return rc;
1681         }
1682
1683         ad.u.fs.path.dentry = new_dentry;
1684         av = DIR__ADD_NAME | DIR__SEARCH;
1685         if (new_dentry->d_inode)
1686                 av |= DIR__REMOVE_NAME;
1687         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1688         if (rc)
1689                 return rc;
1690         if (new_dentry->d_inode) {
1691                 new_isec = new_dentry->d_inode->i_security;
1692                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1693                 rc = avc_has_perm(sid, new_isec->sid,
1694                                   new_isec->sclass,
1695                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1696                 if (rc)
1697                         return rc;
1698         }
1699
1700         return 0;
1701 }
1702
1703 /* Check whether a task can perform a filesystem operation. */
1704 static int superblock_has_perm(const struct cred *cred,
1705                                struct super_block *sb,
1706                                u32 perms,
1707                                struct common_audit_data *ad)
1708 {
1709         struct superblock_security_struct *sbsec;
1710         u32 sid = cred_sid(cred);
1711
1712         sbsec = sb->s_security;
1713         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1714 }
1715
1716 /* Convert a Linux mode and permission mask to an access vector. */
1717 static inline u32 file_mask_to_av(int mode, int mask)
1718 {
1719         u32 av = 0;
1720
1721         if ((mode & S_IFMT) != S_IFDIR) {
1722                 if (mask & MAY_EXEC)
1723                         av |= FILE__EXECUTE;
1724                 if (mask & MAY_READ)
1725                         av |= FILE__READ;
1726
1727                 if (mask & MAY_APPEND)
1728                         av |= FILE__APPEND;
1729                 else if (mask & MAY_WRITE)
1730                         av |= FILE__WRITE;
1731
1732         } else {
1733                 if (mask & MAY_EXEC)
1734                         av |= DIR__SEARCH;
1735                 if (mask & MAY_WRITE)
1736                         av |= DIR__WRITE;
1737                 if (mask & MAY_READ)
1738                         av |= DIR__READ;
1739         }
1740
1741         return av;
1742 }
1743
1744 /* Convert a Linux file to an access vector. */
1745 static inline u32 file_to_av(struct file *file)
1746 {
1747         u32 av = 0;
1748
1749         if (file->f_mode & FMODE_READ)
1750                 av |= FILE__READ;
1751         if (file->f_mode & FMODE_WRITE) {
1752                 if (file->f_flags & O_APPEND)
1753                         av |= FILE__APPEND;
1754                 else
1755                         av |= FILE__WRITE;
1756         }
1757         if (!av) {
1758                 /*
1759                  * Special file opened with flags 3 for ioctl-only use.
1760                  */
1761                 av = FILE__IOCTL;
1762         }
1763
1764         return av;
1765 }
1766
1767 /*
1768  * Convert a file to an access vector and include the correct open
1769  * open permission.
1770  */
1771 static inline u32 open_file_to_av(struct file *file)
1772 {
1773         u32 av = file_to_av(file);
1774
1775         if (selinux_policycap_openperm)
1776                 av |= FILE__OPEN;
1777
1778         return av;
1779 }
1780
1781 /* Hook functions begin here. */
1782
1783 static int selinux_ptrace_access_check(struct task_struct *child,
1784                                      unsigned int mode)
1785 {
1786         int rc;
1787
1788         rc = cap_ptrace_access_check(child, mode);
1789         if (rc)
1790                 return rc;
1791
1792         if (mode == PTRACE_MODE_READ) {
1793                 u32 sid = current_sid();
1794                 u32 csid = task_sid(child);
1795                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1796         }
1797
1798         return current_has_perm(child, PROCESS__PTRACE);
1799 }
1800
1801 static int selinux_ptrace_traceme(struct task_struct *parent)
1802 {
1803         int rc;
1804
1805         rc = cap_ptrace_traceme(parent);
1806         if (rc)
1807                 return rc;
1808
1809         return task_has_perm(parent, current, PROCESS__PTRACE);
1810 }
1811
1812 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1813                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1814 {
1815         int error;
1816
1817         error = current_has_perm(target, PROCESS__GETCAP);
1818         if (error)
1819                 return error;
1820
1821         return cap_capget(target, effective, inheritable, permitted);
1822 }
1823
1824 static int selinux_capset(struct cred *new, const struct cred *old,
1825                           const kernel_cap_t *effective,
1826                           const kernel_cap_t *inheritable,
1827                           const kernel_cap_t *permitted)
1828 {
1829         int error;
1830
1831         error = cap_capset(new, old,
1832                                       effective, inheritable, permitted);
1833         if (error)
1834                 return error;
1835
1836         return cred_has_perm(old, new, PROCESS__SETCAP);
1837 }
1838
1839 /*
1840  * (This comment used to live with the selinux_task_setuid hook,
1841  * which was removed).
1842  *
1843  * Since setuid only affects the current process, and since the SELinux
1844  * controls are not based on the Linux identity attributes, SELinux does not
1845  * need to control this operation.  However, SELinux does control the use of
1846  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1847  */
1848
1849 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1850                            struct user_namespace *ns, int cap, int audit)
1851 {
1852         int rc;
1853
1854         rc = cap_capable(tsk, cred, ns, cap, audit);
1855         if (rc)
1856                 return rc;
1857
1858         return task_has_capability(tsk, cred, cap, audit);
1859 }
1860
1861 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1862 {
1863         const struct cred *cred = current_cred();
1864         int rc = 0;
1865
1866         if (!sb)
1867                 return 0;
1868
1869         switch (cmds) {
1870         case Q_SYNC:
1871         case Q_QUOTAON:
1872         case Q_QUOTAOFF:
1873         case Q_SETINFO:
1874         case Q_SETQUOTA:
1875                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1876                 break;
1877         case Q_GETFMT:
1878         case Q_GETINFO:
1879         case Q_GETQUOTA:
1880                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1881                 break;
1882         default:
1883                 rc = 0;  /* let the kernel handle invalid cmds */
1884                 break;
1885         }
1886         return rc;
1887 }
1888
1889 static int selinux_quota_on(struct dentry *dentry)
1890 {
1891         const struct cred *cred = current_cred();
1892
1893         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1894 }
1895
1896 static int selinux_syslog(int type)
1897 {
1898         int rc;
1899
1900         switch (type) {
1901         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1902         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1903                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1904                 break;
1905         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1906         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1907         /* Set level of messages printed to console */
1908         case SYSLOG_ACTION_CONSOLE_LEVEL:
1909                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1910                 break;
1911         case SYSLOG_ACTION_CLOSE:       /* Close log */
1912         case SYSLOG_ACTION_OPEN:        /* Open log */
1913         case SYSLOG_ACTION_READ:        /* Read from log */
1914         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1915         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1916         default:
1917                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1918                 break;
1919         }
1920         return rc;
1921 }
1922
1923 /*
1924  * Check that a process has enough memory to allocate a new virtual
1925  * mapping. 0 means there is enough memory for the allocation to
1926  * succeed and -ENOMEM implies there is not.
1927  *
1928  * Do not audit the selinux permission check, as this is applied to all
1929  * processes that allocate mappings.
1930  */
1931 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1932 {
1933         int rc, cap_sys_admin = 0;
1934
1935         rc = selinux_capable(current, current_cred(),
1936                              &init_user_ns, CAP_SYS_ADMIN,
1937                              SECURITY_CAP_NOAUDIT);
1938         if (rc == 0)
1939                 cap_sys_admin = 1;
1940
1941         return __vm_enough_memory(mm, pages, cap_sys_admin);
1942 }
1943
1944 /* binprm security operations */
1945
1946 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1947 {
1948         const struct task_security_struct *old_tsec;
1949         struct task_security_struct *new_tsec;
1950         struct inode_security_struct *isec;
1951         struct common_audit_data ad;
1952         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1953         int rc;
1954
1955         rc = cap_bprm_set_creds(bprm);
1956         if (rc)
1957                 return rc;
1958
1959         /* SELinux context only depends on initial program or script and not
1960          * the script interpreter */
1961         if (bprm->cred_prepared)
1962                 return 0;
1963
1964         old_tsec = current_security();
1965         new_tsec = bprm->cred->security;
1966         isec = inode->i_security;
1967
1968         /* Default to the current task SID. */
1969         new_tsec->sid = old_tsec->sid;
1970         new_tsec->osid = old_tsec->sid;
1971
1972         /* Reset fs, key, and sock SIDs on execve. */
1973         new_tsec->create_sid = 0;
1974         new_tsec->keycreate_sid = 0;
1975         new_tsec->sockcreate_sid = 0;
1976
1977         if (old_tsec->exec_sid) {
1978                 new_tsec->sid = old_tsec->exec_sid;
1979                 /* Reset exec SID on execve. */
1980                 new_tsec->exec_sid = 0;
1981         } else {
1982                 /* Check for a default transition on this program. */
1983                 rc = security_transition_sid(old_tsec->sid, isec->sid,
1984                                              SECCLASS_PROCESS, NULL,
1985                                              &new_tsec->sid);
1986                 if (rc)
1987                         return rc;
1988         }
1989
1990         COMMON_AUDIT_DATA_INIT(&ad, FS);
1991         ad.u.fs.path = bprm->file->f_path;
1992
1993         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
1994                 new_tsec->sid = old_tsec->sid;
1995
1996         if (new_tsec->sid == old_tsec->sid) {
1997                 rc = avc_has_perm(old_tsec->sid, isec->sid,
1998                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1999                 if (rc)
2000                         return rc;
2001         } else {
2002                 /* Check permissions for the transition. */
2003                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2004                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2005                 if (rc)
2006                         return rc;
2007
2008                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2009                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2010                 if (rc)
2011                         return rc;
2012
2013                 /* Check for shared state */
2014                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2015                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2016                                           SECCLASS_PROCESS, PROCESS__SHARE,
2017                                           NULL);
2018                         if (rc)
2019                                 return -EPERM;
2020                 }
2021
2022                 /* Make sure that anyone attempting to ptrace over a task that
2023                  * changes its SID has the appropriate permit */
2024                 if (bprm->unsafe &
2025                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2026                         struct task_struct *tracer;
2027                         struct task_security_struct *sec;
2028                         u32 ptsid = 0;
2029
2030                         rcu_read_lock();
2031                         tracer = tracehook_tracer_task(current);
2032                         if (likely(tracer != NULL)) {
2033                                 sec = __task_cred(tracer)->security;
2034                                 ptsid = sec->sid;
2035                         }
2036                         rcu_read_unlock();
2037
2038                         if (ptsid != 0) {
2039                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2040                                                   SECCLASS_PROCESS,
2041                                                   PROCESS__PTRACE, NULL);
2042                                 if (rc)
2043                                         return -EPERM;
2044                         }
2045                 }
2046
2047                 /* Clear any possibly unsafe personality bits on exec: */
2048                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2049         }
2050
2051         return 0;
2052 }
2053
2054 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2055 {
2056         const struct task_security_struct *tsec = current_security();
2057         u32 sid, osid;
2058         int atsecure = 0;
2059
2060         sid = tsec->sid;
2061         osid = tsec->osid;
2062
2063         if (osid != sid) {
2064                 /* Enable secure mode for SIDs transitions unless
2065                    the noatsecure permission is granted between
2066                    the two SIDs, i.e. ahp returns 0. */
2067                 atsecure = avc_has_perm(osid, sid,
2068                                         SECCLASS_PROCESS,
2069                                         PROCESS__NOATSECURE, NULL);
2070         }
2071
2072         return (atsecure || cap_bprm_secureexec(bprm));
2073 }
2074
2075 extern struct vfsmount *selinuxfs_mount;
2076 extern struct dentry *selinux_null;
2077
2078 /* Derived from fs/exec.c:flush_old_files. */
2079 static inline void flush_unauthorized_files(const struct cred *cred,
2080                                             struct files_struct *files)
2081 {
2082         struct common_audit_data ad;
2083         struct file *file, *devnull = NULL;
2084         struct tty_struct *tty;
2085         struct fdtable *fdt;
2086         long j = -1;
2087         int drop_tty = 0;
2088
2089         tty = get_current_tty();
2090         if (tty) {
2091                 spin_lock(&tty_files_lock);
2092                 if (!list_empty(&tty->tty_files)) {
2093                         struct tty_file_private *file_priv;
2094                         struct inode *inode;
2095
2096                         /* Revalidate access to controlling tty.
2097                            Use inode_has_perm on the tty inode directly rather
2098                            than using file_has_perm, as this particular open
2099                            file may belong to another process and we are only
2100                            interested in the inode-based check here. */
2101                         file_priv = list_first_entry(&tty->tty_files,
2102                                                 struct tty_file_private, list);
2103                         file = file_priv->file;
2104                         inode = file->f_path.dentry->d_inode;
2105                         if (inode_has_perm(cred, inode,
2106                                            FILE__READ | FILE__WRITE, NULL)) {
2107                                 drop_tty = 1;
2108                         }
2109                 }
2110                 spin_unlock(&tty_files_lock);
2111                 tty_kref_put(tty);
2112         }
2113         /* Reset controlling tty. */
2114         if (drop_tty)
2115                 no_tty();
2116
2117         /* Revalidate access to inherited open files. */
2118
2119         COMMON_AUDIT_DATA_INIT(&ad, FS);
2120
2121         spin_lock(&files->file_lock);
2122         for (;;) {
2123                 unsigned long set, i;
2124                 int fd;
2125
2126                 j++;
2127                 i = j * __NFDBITS;
2128                 fdt = files_fdtable(files);
2129                 if (i >= fdt->max_fds)
2130                         break;
2131                 set = fdt->open_fds->fds_bits[j];
2132                 if (!set)
2133                         continue;
2134                 spin_unlock(&files->file_lock);
2135                 for ( ; set ; i++, set >>= 1) {
2136                         if (set & 1) {
2137                                 file = fget(i);
2138                                 if (!file)
2139                                         continue;
2140                                 if (file_has_perm(cred,
2141                                                   file,
2142                                                   file_to_av(file))) {
2143                                         sys_close(i);
2144                                         fd = get_unused_fd();
2145                                         if (fd != i) {
2146                                                 if (fd >= 0)
2147                                                         put_unused_fd(fd);
2148                                                 fput(file);
2149                                                 continue;
2150                                         }
2151                                         if (devnull) {
2152                                                 get_file(devnull);
2153                                         } else {
2154                                                 devnull = dentry_open(
2155                                                         dget(selinux_null),
2156                                                         mntget(selinuxfs_mount),
2157                                                         O_RDWR, cred);
2158                                                 if (IS_ERR(devnull)) {
2159                                                         devnull = NULL;
2160                                                         put_unused_fd(fd);
2161                                                         fput(file);
2162                                                         continue;
2163                                                 }
2164                                         }
2165                                         fd_install(fd, devnull);
2166                                 }
2167                                 fput(file);
2168                         }
2169                 }
2170                 spin_lock(&files->file_lock);
2171
2172         }
2173         spin_unlock(&files->file_lock);
2174 }
2175
2176 /*
2177  * Prepare a process for imminent new credential changes due to exec
2178  */
2179 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2180 {
2181         struct task_security_struct *new_tsec;
2182         struct rlimit *rlim, *initrlim;
2183         int rc, i;
2184
2185         new_tsec = bprm->cred->security;
2186         if (new_tsec->sid == new_tsec->osid)
2187                 return;
2188
2189         /* Close files for which the new task SID is not authorized. */
2190         flush_unauthorized_files(bprm->cred, current->files);
2191
2192         /* Always clear parent death signal on SID transitions. */
2193         current->pdeath_signal = 0;
2194
2195         /* Check whether the new SID can inherit resource limits from the old
2196          * SID.  If not, reset all soft limits to the lower of the current
2197          * task's hard limit and the init task's soft limit.
2198          *
2199          * Note that the setting of hard limits (even to lower them) can be
2200          * controlled by the setrlimit check.  The inclusion of the init task's
2201          * soft limit into the computation is to avoid resetting soft limits
2202          * higher than the default soft limit for cases where the default is
2203          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2204          */
2205         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2206                           PROCESS__RLIMITINH, NULL);
2207         if (rc) {
2208                 /* protect against do_prlimit() */
2209                 task_lock(current);
2210                 for (i = 0; i < RLIM_NLIMITS; i++) {
2211                         rlim = current->signal->rlim + i;
2212                         initrlim = init_task.signal->rlim + i;
2213                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2214                 }
2215                 task_unlock(current);
2216                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2217         }
2218 }
2219
2220 /*
2221  * Clean up the process immediately after the installation of new credentials
2222  * due to exec
2223  */
2224 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2225 {
2226         const struct task_security_struct *tsec = current_security();
2227         struct itimerval itimer;
2228         u32 osid, sid;
2229         int rc, i;
2230
2231         osid = tsec->osid;
2232         sid = tsec->sid;
2233
2234         if (sid == osid)
2235                 return;
2236
2237         /* Check whether the new SID can inherit signal state from the old SID.
2238          * If not, clear itimers to avoid subsequent signal generation and
2239          * flush and unblock signals.
2240          *
2241          * This must occur _after_ the task SID has been updated so that any
2242          * kill done after the flush will be checked against the new SID.
2243          */
2244         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2245         if (rc) {
2246                 memset(&itimer, 0, sizeof itimer);
2247                 for (i = 0; i < 3; i++)
2248                         do_setitimer(i, &itimer, NULL);
2249                 spin_lock_irq(&current->sighand->siglock);
2250                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2251                         __flush_signals(current);
2252                         flush_signal_handlers(current, 1);
2253                         sigemptyset(&current->blocked);
2254                 }
2255                 spin_unlock_irq(&current->sighand->siglock);
2256         }
2257
2258         /* Wake up the parent if it is waiting so that it can recheck
2259          * wait permission to the new task SID. */
2260         read_lock(&tasklist_lock);
2261         __wake_up_parent(current, current->real_parent);
2262         read_unlock(&tasklist_lock);
2263 }
2264
2265 /* superblock security operations */
2266
2267 static int selinux_sb_alloc_security(struct super_block *sb)
2268 {
2269         return superblock_alloc_security(sb);
2270 }
2271
2272 static void selinux_sb_free_security(struct super_block *sb)
2273 {
2274         superblock_free_security(sb);
2275 }
2276
2277 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2278 {
2279         if (plen > olen)
2280                 return 0;
2281
2282         return !memcmp(prefix, option, plen);
2283 }
2284
2285 static inline int selinux_option(char *option, int len)
2286 {
2287         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2288                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2289                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2290                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2291                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2292 }
2293
2294 static inline void take_option(char **to, char *from, int *first, int len)
2295 {
2296         if (!*first) {
2297                 **to = ',';
2298                 *to += 1;
2299         } else
2300                 *first = 0;
2301         memcpy(*to, from, len);
2302         *to += len;
2303 }
2304
2305 static inline void take_selinux_option(char **to, char *from, int *first,
2306                                        int len)
2307 {
2308         int current_size = 0;
2309
2310         if (!*first) {
2311                 **to = '|';
2312                 *to += 1;
2313         } else
2314                 *first = 0;
2315
2316         while (current_size < len) {
2317                 if (*from != '"') {
2318                         **to = *from;
2319                         *to += 1;
2320                 }
2321                 from += 1;
2322                 current_size += 1;
2323         }
2324 }
2325
2326 static int selinux_sb_copy_data(char *orig, char *copy)
2327 {
2328         int fnosec, fsec, rc = 0;
2329         char *in_save, *in_curr, *in_end;
2330         char *sec_curr, *nosec_save, *nosec;
2331         int open_quote = 0;
2332
2333         in_curr = orig;
2334         sec_curr = copy;
2335
2336         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2337         if (!nosec) {
2338                 rc = -ENOMEM;
2339                 goto out;
2340         }
2341
2342         nosec_save = nosec;
2343         fnosec = fsec = 1;
2344         in_save = in_end = orig;
2345
2346         do {
2347                 if (*in_end == '"')
2348                         open_quote = !open_quote;
2349                 if ((*in_end == ',' && open_quote == 0) ||
2350                                 *in_end == '\0') {
2351                         int len = in_end - in_curr;
2352
2353                         if (selinux_option(in_curr, len))
2354                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2355                         else
2356                                 take_option(&nosec, in_curr, &fnosec, len);
2357
2358                         in_curr = in_end + 1;
2359                 }
2360         } while (*in_end++);
2361
2362         strcpy(in_save, nosec_save);
2363         free_page((unsigned long)nosec_save);
2364 out:
2365         return rc;
2366 }
2367
2368 static int selinux_sb_remount(struct super_block *sb, void *data)
2369 {
2370         int rc, i, *flags;
2371         struct security_mnt_opts opts;
2372         char *secdata, **mount_options;
2373         struct superblock_security_struct *sbsec = sb->s_security;
2374
2375         if (!(sbsec->flags & SE_SBINITIALIZED))
2376                 return 0;
2377
2378         if (!data)
2379                 return 0;
2380
2381         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2382                 return 0;
2383
2384         security_init_mnt_opts(&opts);
2385         secdata = alloc_secdata();
2386         if (!secdata)
2387                 return -ENOMEM;
2388         rc = selinux_sb_copy_data(data, secdata);
2389         if (rc)
2390                 goto out_free_secdata;
2391
2392         rc = selinux_parse_opts_str(secdata, &opts);
2393         if (rc)
2394                 goto out_free_secdata;
2395
2396         mount_options = opts.mnt_opts;
2397         flags = opts.mnt_opts_flags;
2398
2399         for (i = 0; i < opts.num_mnt_opts; i++) {
2400                 u32 sid;
2401                 size_t len;
2402
2403                 if (flags[i] == SE_SBLABELSUPP)
2404                         continue;
2405                 len = strlen(mount_options[i]);
2406                 rc = security_context_to_sid(mount_options[i], len, &sid);
2407                 if (rc) {
2408                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2409                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2410                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2411                         goto out_free_opts;
2412                 }
2413                 rc = -EINVAL;
2414                 switch (flags[i]) {
2415                 case FSCONTEXT_MNT:
2416                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2417                                 goto out_bad_option;
2418                         break;
2419                 case CONTEXT_MNT:
2420                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2421                                 goto out_bad_option;
2422                         break;
2423                 case ROOTCONTEXT_MNT: {
2424                         struct inode_security_struct *root_isec;
2425                         root_isec = sb->s_root->d_inode->i_security;
2426
2427                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2428                                 goto out_bad_option;
2429                         break;
2430                 }
2431                 case DEFCONTEXT_MNT:
2432                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2433                                 goto out_bad_option;
2434                         break;
2435                 default:
2436                         goto out_free_opts;
2437                 }
2438         }
2439
2440         rc = 0;
2441 out_free_opts:
2442         security_free_mnt_opts(&opts);
2443 out_free_secdata:
2444         free_secdata(secdata);
2445         return rc;
2446 out_bad_option:
2447         printk(KERN_WARNING "SELinux: unable to change security options "
2448                "during remount (dev %s, type=%s)\n", sb->s_id,
2449                sb->s_type->name);
2450         goto out_free_opts;
2451 }
2452
2453 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2454 {
2455         const struct cred *cred = current_cred();
2456         struct common_audit_data ad;
2457         int rc;
2458
2459         rc = superblock_doinit(sb, data);
2460         if (rc)
2461                 return rc;
2462
2463         /* Allow all mounts performed by the kernel */
2464         if (flags & MS_KERNMOUNT)
2465                 return 0;
2466
2467         COMMON_AUDIT_DATA_INIT(&ad, FS);
2468         ad.u.fs.path.dentry = sb->s_root;
2469         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2470 }
2471
2472 static int selinux_sb_statfs(struct dentry *dentry)
2473 {
2474         const struct cred *cred = current_cred();
2475         struct common_audit_data ad;
2476
2477         COMMON_AUDIT_DATA_INIT(&ad, FS);
2478         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2479         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2480 }
2481
2482 static int selinux_mount(char *dev_name,
2483                          struct path *path,
2484                          char *type,
2485                          unsigned long flags,
2486                          void *data)
2487 {
2488         const struct cred *cred = current_cred();
2489
2490         if (flags & MS_REMOUNT)
2491                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2492                                            FILESYSTEM__REMOUNT, NULL);
2493         else
2494                 return dentry_has_perm(cred, path->mnt, path->dentry,
2495                                        FILE__MOUNTON);
2496 }
2497
2498 static int selinux_umount(struct vfsmount *mnt, int flags)
2499 {
2500         const struct cred *cred = current_cred();
2501
2502         return superblock_has_perm(cred, mnt->mnt_sb,
2503                                    FILESYSTEM__UNMOUNT, NULL);
2504 }
2505
2506 /* inode security operations */
2507
2508 static int selinux_inode_alloc_security(struct inode *inode)
2509 {
2510         return inode_alloc_security(inode);
2511 }
2512
2513 static void selinux_inode_free_security(struct inode *inode)
2514 {
2515         inode_free_security(inode);
2516 }
2517
2518 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2519                                        const struct qstr *qstr, char **name,
2520                                        void **value, size_t *len)
2521 {
2522         const struct task_security_struct *tsec = current_security();
2523         struct inode_security_struct *dsec;
2524         struct superblock_security_struct *sbsec;
2525         u32 sid, newsid, clen;
2526         int rc;
2527         char *namep = NULL, *context;
2528
2529         dsec = dir->i_security;
2530         sbsec = dir->i_sb->s_security;
2531
2532         sid = tsec->sid;
2533         newsid = tsec->create_sid;
2534
2535         if ((sbsec->flags & SE_SBINITIALIZED) &&
2536             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2537                 newsid = sbsec->mntpoint_sid;
2538         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2539                 rc = security_transition_sid(sid, dsec->sid,
2540                                              inode_mode_to_security_class(inode->i_mode),
2541                                              qstr, &newsid);
2542                 if (rc) {
2543                         printk(KERN_WARNING "%s:  "
2544                                "security_transition_sid failed, rc=%d (dev=%s "
2545                                "ino=%ld)\n",
2546                                __func__,
2547                                -rc, inode->i_sb->s_id, inode->i_ino);
2548                         return rc;
2549                 }
2550         }
2551
2552         /* Possibly defer initialization to selinux_complete_init. */
2553         if (sbsec->flags & SE_SBINITIALIZED) {
2554                 struct inode_security_struct *isec = inode->i_security;
2555                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2556                 isec->sid = newsid;
2557                 isec->initialized = 1;
2558         }
2559
2560         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2561                 return -EOPNOTSUPP;
2562
2563         if (name) {
2564                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2565                 if (!namep)
2566                         return -ENOMEM;
2567                 *name = namep;
2568         }
2569
2570         if (value && len) {
2571                 rc = security_sid_to_context_force(newsid, &context, &clen);
2572                 if (rc) {
2573                         kfree(namep);
2574                         return rc;
2575                 }
2576                 *value = context;
2577                 *len = clen;
2578         }
2579
2580         return 0;
2581 }
2582
2583 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2584 {
2585         return may_create(dir, dentry, SECCLASS_FILE);
2586 }
2587
2588 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2589 {
2590         return may_link(dir, old_dentry, MAY_LINK);
2591 }
2592
2593 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2594 {
2595         return may_link(dir, dentry, MAY_UNLINK);
2596 }
2597
2598 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2599 {
2600         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2601 }
2602
2603 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2604 {
2605         return may_create(dir, dentry, SECCLASS_DIR);
2606 }
2607
2608 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2609 {
2610         return may_link(dir, dentry, MAY_RMDIR);
2611 }
2612
2613 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2614 {
2615         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2616 }
2617
2618 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2619                                 struct inode *new_inode, struct dentry *new_dentry)
2620 {
2621         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2622 }
2623
2624 static int selinux_inode_readlink(struct dentry *dentry)
2625 {
2626         const struct cred *cred = current_cred();
2627
2628         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2629 }
2630
2631 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2632 {
2633         const struct cred *cred = current_cred();
2634
2635         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2636 }
2637
2638 static int selinux_inode_permission(struct inode *inode, int mask)
2639 {
2640         const struct cred *cred = current_cred();
2641         struct common_audit_data ad;
2642         u32 perms;
2643         bool from_access;
2644
2645         from_access = mask & MAY_ACCESS;
2646         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2647
2648         /* No permission to check.  Existence test. */
2649         if (!mask)
2650                 return 0;
2651
2652         COMMON_AUDIT_DATA_INIT(&ad, FS);
2653         ad.u.fs.inode = inode;
2654
2655         if (from_access)
2656                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2657
2658         perms = file_mask_to_av(inode->i_mode, mask);
2659
2660         return inode_has_perm(cred, inode, perms, &ad);
2661 }
2662
2663 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2664 {
2665         const struct cred *cred = current_cred();
2666         unsigned int ia_valid = iattr->ia_valid;
2667
2668         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2669         if (ia_valid & ATTR_FORCE) {
2670                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2671                               ATTR_FORCE);
2672                 if (!ia_valid)
2673                         return 0;
2674         }
2675
2676         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2677                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2678                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2679
2680         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2681 }
2682
2683 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2684 {
2685         const struct cred *cred = current_cred();
2686
2687         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2688 }
2689
2690 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2691 {
2692         const struct cred *cred = current_cred();
2693
2694         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2695                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2696                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2697                         if (!capable(CAP_SETFCAP))
2698                                 return -EPERM;
2699                 } else if (!capable(CAP_SYS_ADMIN)) {
2700                         /* A different attribute in the security namespace.
2701                            Restrict to administrator. */
2702                         return -EPERM;
2703                 }
2704         }
2705
2706         /* Not an attribute we recognize, so just check the
2707            ordinary setattr permission. */
2708         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2709 }
2710
2711 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2712                                   const void *value, size_t size, int flags)
2713 {
2714         struct inode *inode = dentry->d_inode;
2715         struct inode_security_struct *isec = inode->i_security;
2716         struct superblock_security_struct *sbsec;
2717         struct common_audit_data ad;
2718         u32 newsid, sid = current_sid();
2719         int rc = 0;
2720
2721         if (strcmp(name, XATTR_NAME_SELINUX))
2722                 return selinux_inode_setotherxattr(dentry, name);
2723
2724         sbsec = inode->i_sb->s_security;
2725         if (!(sbsec->flags & SE_SBLABELSUPP))
2726                 return -EOPNOTSUPP;
2727
2728         if (!is_owner_or_cap(inode))
2729                 return -EPERM;
2730
2731         COMMON_AUDIT_DATA_INIT(&ad, FS);
2732         ad.u.fs.path.dentry = dentry;
2733
2734         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2735                           FILE__RELABELFROM, &ad);
2736         if (rc)
2737                 return rc;
2738
2739         rc = security_context_to_sid(value, size, &newsid);
2740         if (rc == -EINVAL) {
2741                 if (!capable(CAP_MAC_ADMIN))
2742                         return rc;
2743                 rc = security_context_to_sid_force(value, size, &newsid);
2744         }
2745         if (rc)
2746                 return rc;
2747
2748         rc = avc_has_perm(sid, newsid, isec->sclass,
2749                           FILE__RELABELTO, &ad);
2750         if (rc)
2751                 return rc;
2752
2753         rc = security_validate_transition(isec->sid, newsid, sid,
2754                                           isec->sclass);
2755         if (rc)
2756                 return rc;
2757
2758         return avc_has_perm(newsid,
2759                             sbsec->sid,
2760                             SECCLASS_FILESYSTEM,
2761                             FILESYSTEM__ASSOCIATE,
2762                             &ad);
2763 }
2764
2765 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2766                                         const void *value, size_t size,
2767                                         int flags)
2768 {
2769         struct inode *inode = dentry->d_inode;
2770         struct inode_security_struct *isec = inode->i_security;
2771         u32 newsid;
2772         int rc;
2773
2774         if (strcmp(name, XATTR_NAME_SELINUX)) {
2775                 /* Not an attribute we recognize, so nothing to do. */
2776                 return;
2777         }
2778
2779         rc = security_context_to_sid_force(value, size, &newsid);
2780         if (rc) {
2781                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2782                        "for (%s, %lu), rc=%d\n",
2783                        inode->i_sb->s_id, inode->i_ino, -rc);
2784                 return;
2785         }
2786
2787         isec->sid = newsid;
2788         return;
2789 }
2790
2791 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2792 {
2793         const struct cred *cred = current_cred();
2794
2795         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2796 }
2797
2798 static int selinux_inode_listxattr(struct dentry *dentry)
2799 {
2800         const struct cred *cred = current_cred();
2801
2802         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2803 }
2804
2805 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2806 {
2807         if (strcmp(name, XATTR_NAME_SELINUX))
2808                 return selinux_inode_setotherxattr(dentry, name);
2809
2810         /* No one is allowed to remove a SELinux security label.
2811            You can change the label, but all data must be labeled. */
2812         return -EACCES;
2813 }
2814
2815 /*
2816  * Copy the inode security context value to the user.
2817  *
2818  * Permission check is handled by selinux_inode_getxattr hook.
2819  */
2820 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2821 {
2822         u32 size;
2823         int error;
2824         char *context = NULL;
2825         struct inode_security_struct *isec = inode->i_security;
2826
2827         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2828                 return -EOPNOTSUPP;
2829
2830         /*
2831          * If the caller has CAP_MAC_ADMIN, then get the raw context
2832          * value even if it is not defined by current policy; otherwise,
2833          * use the in-core value under current policy.
2834          * Use the non-auditing forms of the permission checks since
2835          * getxattr may be called by unprivileged processes commonly
2836          * and lack of permission just means that we fall back to the
2837          * in-core context value, not a denial.
2838          */
2839         error = selinux_capable(current, current_cred(),
2840                                 &init_user_ns, CAP_MAC_ADMIN,
2841                                 SECURITY_CAP_NOAUDIT);
2842         if (!error)
2843                 error = security_sid_to_context_force(isec->sid, &context,
2844                                                       &size);
2845         else
2846                 error = security_sid_to_context(isec->sid, &context, &size);
2847         if (error)
2848                 return error;
2849         error = size;
2850         if (alloc) {
2851                 *buffer = context;
2852                 goto out_nofree;
2853         }
2854         kfree(context);
2855 out_nofree:
2856         return error;
2857 }
2858
2859 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2860                                      const void *value, size_t size, int flags)
2861 {
2862         struct inode_security_struct *isec = inode->i_security;
2863         u32 newsid;
2864         int rc;
2865
2866         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2867                 return -EOPNOTSUPP;
2868
2869         if (!value || !size)
2870                 return -EACCES;
2871
2872         rc = security_context_to_sid((void *)value, size, &newsid);
2873         if (rc)
2874                 return rc;
2875
2876         isec->sid = newsid;
2877         isec->initialized = 1;
2878         return 0;
2879 }
2880
2881 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2882 {
2883         const int len = sizeof(XATTR_NAME_SELINUX);
2884         if (buffer && len <= buffer_size)
2885                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2886         return len;
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         const struct cred *cred = current_cred();
2900         struct inode *inode = file->f_path.dentry->d_inode;
2901
2902         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2903         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2904                 mask |= MAY_APPEND;
2905
2906         return file_has_perm(cred, file,
2907                              file_mask_to_av(inode->i_mode, mask));
2908 }
2909
2910 static int selinux_file_permission(struct file *file, int mask)
2911 {
2912         struct inode *inode = file->f_path.dentry->d_inode;
2913         struct file_security_struct *fsec = file->f_security;
2914         struct inode_security_struct *isec = inode->i_security;
2915         u32 sid = current_sid();
2916
2917         if (!mask)
2918                 /* No permission to check.  Existence test. */
2919                 return 0;
2920
2921         if (sid == fsec->sid && fsec->isid == isec->sid &&
2922             fsec->pseqno == avc_policy_seqno())
2923                 /* No change since dentry_open check. */
2924                 return 0;
2925
2926         return selinux_revalidate_file_permission(file, mask);
2927 }
2928
2929 static int selinux_file_alloc_security(struct file *file)
2930 {
2931         return file_alloc_security(file);
2932 }
2933
2934 static void selinux_file_free_security(struct file *file)
2935 {
2936         file_free_security(file);
2937 }
2938
2939 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2940                               unsigned long arg)
2941 {
2942         const struct cred *cred = current_cred();
2943         int error = 0;
2944
2945         switch (cmd) {
2946         case FIONREAD:
2947         /* fall through */
2948         case FIBMAP:
2949         /* fall through */
2950         case FIGETBSZ:
2951         /* fall through */
2952         case EXT2_IOC_GETFLAGS:
2953         /* fall through */
2954         case EXT2_IOC_GETVERSION:
2955                 error = file_has_perm(cred, file, FILE__GETATTR);
2956                 break;
2957
2958         case EXT2_IOC_SETFLAGS:
2959         /* fall through */
2960         case EXT2_IOC_SETVERSION:
2961                 error = file_has_perm(cred, file, FILE__SETATTR);
2962                 break;
2963
2964         /* sys_ioctl() checks */
2965         case FIONBIO:
2966         /* fall through */
2967         case FIOASYNC:
2968                 error = file_has_perm(cred, file, 0);
2969                 break;
2970
2971         case KDSKBENT:
2972         case KDSKBSENT:
2973                 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
2974                                         SECURITY_CAP_AUDIT);
2975                 break;
2976
2977         /* default case assumes that the command will go
2978          * to the file's ioctl() function.
2979          */
2980         default:
2981                 error = file_has_perm(cred, file, FILE__IOCTL);
2982         }
2983         return error;
2984 }
2985
2986 static int default_noexec;
2987
2988 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2989 {
2990         const struct cred *cred = current_cred();
2991         int rc = 0;
2992
2993         if (default_noexec &&
2994             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2995                 /*
2996                  * We are making executable an anonymous mapping or a
2997                  * private file mapping that will also be writable.
2998                  * This has an additional check.
2999                  */
3000                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3001                 if (rc)
3002                         goto error;
3003         }
3004
3005         if (file) {
3006                 /* read access is always possible with a mapping */
3007                 u32 av = FILE__READ;
3008
3009                 /* write access only matters if the mapping is shared */
3010                 if (shared && (prot & PROT_WRITE))
3011                         av |= FILE__WRITE;
3012
3013                 if (prot & PROT_EXEC)
3014                         av |= FILE__EXECUTE;
3015
3016                 return file_has_perm(cred, file, av);
3017         }
3018
3019 error:
3020         return rc;
3021 }
3022
3023 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3024                              unsigned long prot, unsigned long flags,
3025                              unsigned long addr, unsigned long addr_only)
3026 {
3027         int rc = 0;
3028         u32 sid = current_sid();
3029
3030         /*
3031          * notice that we are intentionally putting the SELinux check before
3032          * the secondary cap_file_mmap check.  This is such a likely attempt
3033          * at bad behaviour/exploit that we always want to get the AVC, even
3034          * if DAC would have also denied the operation.
3035          */
3036         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3037                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3038                                   MEMPROTECT__MMAP_ZERO, NULL);
3039                 if (rc)
3040                         return rc;
3041         }
3042
3043         /* do DAC check on address space usage */
3044         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3045         if (rc || addr_only)
3046                 return rc;
3047
3048         if (selinux_checkreqprot)
3049                 prot = reqprot;
3050
3051         return file_map_prot_check(file, prot,
3052                                    (flags & MAP_TYPE) == MAP_SHARED);
3053 }
3054
3055 static int selinux_file_mprotect(struct vm_area_struct *vma,
3056                                  unsigned long reqprot,
3057                                  unsigned long prot)
3058 {
3059         const struct cred *cred = current_cred();
3060
3061         if (selinux_checkreqprot)
3062                 prot = reqprot;
3063
3064         if (default_noexec &&
3065             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3066                 int rc = 0;
3067                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3068                     vma->vm_end <= vma->vm_mm->brk) {
3069                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3070                 } else if (!vma->vm_file &&
3071                            vma->vm_start <= vma->vm_mm->start_stack &&
3072                            vma->vm_end >= vma->vm_mm->start_stack) {
3073                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3074                 } else if (vma->vm_file && vma->anon_vma) {
3075                         /*
3076                          * We are making executable a file mapping that has
3077                          * had some COW done. Since pages might have been
3078                          * written, check ability to execute the possibly
3079                          * modified content.  This typically should only
3080                          * occur for text relocations.
3081                          */
3082                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3083                 }
3084                 if (rc)
3085                         return rc;
3086         }
3087
3088         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3089 }
3090
3091 static int selinux_file_lock(struct file *file, unsigned int cmd)
3092 {
3093         const struct cred *cred = current_cred();
3094
3095         return file_has_perm(cred, file, FILE__LOCK);
3096 }
3097
3098 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3099                               unsigned long arg)
3100 {
3101         const struct cred *cred = current_cred();
3102         int err = 0;
3103
3104         switch (cmd) {
3105         case F_SETFL:
3106                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3107                         err = -EINVAL;
3108                         break;
3109                 }
3110
3111                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3112                         err = file_has_perm(cred, file, FILE__WRITE);
3113                         break;
3114                 }
3115                 /* fall through */
3116         case F_SETOWN:
3117         case F_SETSIG:
3118         case F_GETFL:
3119         case F_GETOWN:
3120         case F_GETSIG:
3121                 /* Just check FD__USE permission */
3122                 err = file_has_perm(cred, file, 0);
3123                 break;
3124         case F_GETLK:
3125         case F_SETLK:
3126         case F_SETLKW:
3127 #if BITS_PER_LONG == 32
3128         case F_GETLK64:
3129         case F_SETLK64:
3130         case F_SETLKW64:
3131 #endif
3132                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3133                         err = -EINVAL;
3134                         break;
3135                 }
3136                 err = file_has_perm(cred, file, FILE__LOCK);
3137                 break;
3138         }
3139
3140         return err;
3141 }
3142
3143 static int selinux_file_set_fowner(struct file *file)
3144 {
3145         struct file_security_struct *fsec;
3146
3147         fsec = file->f_security;
3148         fsec->fown_sid = current_sid();
3149
3150         return 0;
3151 }
3152
3153 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3154                                        struct fown_struct *fown, int signum)
3155 {
3156         struct file *file;
3157         u32 sid = task_sid(tsk);
3158         u32 perm;
3159         struct file_security_struct *fsec;
3160
3161         /* struct fown_struct is never outside the context of a struct file */
3162         file = container_of(fown, struct file, f_owner);
3163
3164         fsec = file->f_security;
3165
3166         if (!signum)
3167                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3168         else
3169                 perm = signal_to_av(signum);
3170
3171         return avc_has_perm(fsec->fown_sid, sid,
3172                             SECCLASS_PROCESS, perm, NULL);
3173 }
3174
3175 static int selinux_file_receive(struct file *file)
3176 {
3177         const struct cred *cred = current_cred();
3178
3179         return file_has_perm(cred, file, file_to_av(file));
3180 }
3181
3182 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3183 {
3184         struct file_security_struct *fsec;
3185         struct inode *inode;
3186         struct inode_security_struct *isec;
3187
3188         inode = file->f_path.dentry->d_inode;
3189         fsec = file->f_security;
3190         isec = inode->i_security;
3191         /*
3192          * Save inode label and policy sequence number
3193          * at open-time so that selinux_file_permission
3194          * can determine whether revalidation is necessary.
3195          * Task label is already saved in the file security
3196          * struct as its SID.
3197          */
3198         fsec->isid = isec->sid;
3199         fsec->pseqno = avc_policy_seqno();
3200         /*
3201          * Since the inode label or policy seqno may have changed
3202          * between the selinux_inode_permission check and the saving
3203          * of state above, recheck that access is still permitted.
3204          * Otherwise, access might never be revalidated against the
3205          * new inode label or new policy.
3206          * This check is not redundant - do not remove.
3207          */
3208         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3209 }
3210
3211 /* task security operations */
3212
3213 static int selinux_task_create(unsigned long clone_flags)
3214 {
3215         return current_has_perm(current, PROCESS__FORK);
3216 }
3217
3218 /*
3219  * allocate the SELinux part of blank credentials
3220  */
3221 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3222 {
3223         struct task_security_struct *tsec;
3224
3225         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3226         if (!tsec)
3227                 return -ENOMEM;
3228
3229         cred->security = tsec;
3230         return 0;
3231 }
3232
3233 /*
3234  * detach and free the LSM part of a set of credentials
3235  */
3236 static void selinux_cred_free(struct cred *cred)
3237 {
3238         struct task_security_struct *tsec = cred->security;
3239
3240         /*
3241          * cred->security == NULL if security_cred_alloc_blank() or
3242          * security_prepare_creds() returned an error.
3243          */
3244         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3245         cred->security = (void *) 0x7UL;
3246         kfree(tsec);
3247 }
3248
3249 /*
3250  * prepare a new set of credentials for modification
3251  */
3252 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3253                                 gfp_t gfp)
3254 {
3255         const struct task_security_struct *old_tsec;
3256         struct task_security_struct *tsec;
3257
3258         old_tsec = old->security;
3259
3260         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3261         if (!tsec)
3262                 return -ENOMEM;
3263
3264         new->security = tsec;
3265         return 0;
3266 }
3267
3268 /*
3269  * transfer the SELinux data to a blank set of creds
3270  */
3271 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3272 {
3273         const struct task_security_struct *old_tsec = old->security;
3274         struct task_security_struct *tsec = new->security;
3275
3276         *tsec = *old_tsec;
3277 }
3278
3279 /*
3280  * set the security data for a kernel service
3281  * - all the creation contexts are set to unlabelled
3282  */
3283 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3284 {
3285         struct task_security_struct *tsec = new->security;
3286         u32 sid = current_sid();
3287         int ret;
3288
3289         ret = avc_has_perm(sid, secid,
3290                            SECCLASS_KERNEL_SERVICE,
3291                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3292                            NULL);
3293         if (ret == 0) {
3294                 tsec->sid = secid;
3295                 tsec->create_sid = 0;
3296                 tsec->keycreate_sid = 0;
3297                 tsec->sockcreate_sid = 0;
3298         }
3299         return ret;
3300 }
3301
3302 /*
3303  * set the file creation context in a security record to the same as the
3304  * objective context of the specified inode
3305  */
3306 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3307 {
3308         struct inode_security_struct *isec = inode->i_security;
3309         struct task_security_struct *tsec = new->security;
3310         u32 sid = current_sid();
3311         int ret;
3312
3313         ret = avc_has_perm(sid, isec->sid,
3314                            SECCLASS_KERNEL_SERVICE,
3315                            KERNEL_SERVICE__CREATE_FILES_AS,
3316                            NULL);
3317
3318         if (ret == 0)
3319                 tsec->create_sid = isec->sid;
3320         return ret;
3321 }
3322
3323 static int selinux_kernel_module_request(char *kmod_name)
3324 {
3325         u32 sid;
3326         struct common_audit_data ad;
3327
3328         sid = task_sid(current);
3329
3330         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3331         ad.u.kmod_name = kmod_name;
3332
3333         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3334                             SYSTEM__MODULE_REQUEST, &ad);
3335 }
3336
3337 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3338 {
3339         return current_has_perm(p, PROCESS__SETPGID);
3340 }
3341
3342 static int selinux_task_getpgid(struct task_struct *p)
3343 {
3344         return current_has_perm(p, PROCESS__GETPGID);
3345 }
3346
3347 static int selinux_task_getsid(struct task_struct *p)
3348 {
3349         return current_has_perm(p, PROCESS__GETSESSION);
3350 }
3351
3352 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3353 {
3354         *secid = task_sid(p);
3355 }
3356
3357 static int selinux_task_setnice(struct task_struct *p, int nice)
3358 {
3359         int rc;
3360
3361         rc = cap_task_setnice(p, nice);
3362         if (rc)
3363                 return rc;
3364
3365         return current_has_perm(p, PROCESS__SETSCHED);
3366 }
3367
3368 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3369 {
3370         int rc;
3371
3372         rc = cap_task_setioprio(p, ioprio);
3373         if (rc)
3374                 return rc;
3375
3376         return current_has_perm(p, PROCESS__SETSCHED);
3377 }
3378
3379 static int selinux_task_getioprio(struct task_struct *p)
3380 {
3381         return current_has_perm(p, PROCESS__GETSCHED);
3382 }
3383
3384 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3385                 struct rlimit *new_rlim)
3386 {
3387         struct rlimit *old_rlim = p->signal->rlim + resource;
3388
3389         /* Control the ability to change the hard limit (whether
3390            lowering or raising it), so that the hard limit can
3391            later be used as a safe reset point for the soft limit
3392            upon context transitions.  See selinux_bprm_committing_creds. */
3393         if (old_rlim->rlim_max != new_rlim->rlim_max)
3394                 return current_has_perm(p, PROCESS__SETRLIMIT);
3395
3396         return 0;
3397 }
3398
3399 static int selinux_task_setscheduler(struct task_struct *p)
3400 {
3401         int rc;
3402
3403         rc = cap_task_setscheduler(p);
3404         if (rc)
3405                 return rc;
3406
3407         return current_has_perm(p, PROCESS__SETSCHED);
3408 }
3409
3410 static int selinux_task_getscheduler(struct task_struct *p)
3411 {
3412         return current_has_perm(p, PROCESS__GETSCHED);
3413 }
3414
3415 static int selinux_task_movememory(struct task_struct *p)
3416 {
3417         return current_has_perm(p, PROCESS__SETSCHED);
3418 }
3419
3420 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3421                                 int sig, u32 secid)
3422 {
3423         u32 perm;
3424         int rc;
3425
3426         if (!sig)
3427                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3428         else
3429                 perm = signal_to_av(sig);
3430         if (secid)
3431                 rc = avc_has_perm(secid, task_sid(p),
3432                                   SECCLASS_PROCESS, perm, NULL);
3433         else
3434                 rc = current_has_perm(p, perm);
3435         return rc;
3436 }
3437
3438 static int selinux_task_wait(struct task_struct *p)
3439 {
3440         return task_has_perm(p, current, PROCESS__SIGCHLD);
3441 }
3442
3443 static void selinux_task_to_inode(struct task_struct *p,
3444                                   struct inode *inode)
3445 {
3446         struct inode_security_struct *isec = inode->i_security;
3447         u32 sid = task_sid(p);
3448
3449         isec->sid = sid;
3450         isec->initialized = 1;
3451 }
3452
3453 /* Returns error only if unable to parse addresses */
3454 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3455                         struct common_audit_data *ad, u8 *proto)
3456 {
3457         int offset, ihlen, ret = -EINVAL;
3458         struct iphdr _iph, *ih;
3459
3460         offset = skb_network_offset(skb);
3461         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3462         if (ih == NULL)
3463                 goto out;
3464
3465         ihlen = ih->ihl * 4;
3466         if (ihlen < sizeof(_iph))
3467                 goto out;
3468
3469         ad->u.net.v4info.saddr = ih->saddr;
3470         ad->u.net.v4info.daddr = ih->daddr;
3471         ret = 0;
3472
3473         if (proto)
3474                 *proto = ih->protocol;
3475
3476         switch (ih->protocol) {
3477         case IPPROTO_TCP: {
3478                 struct tcphdr _tcph, *th;
3479
3480                 if (ntohs(ih->frag_off) & IP_OFFSET)
3481                         break;
3482
3483                 offset += ihlen;
3484                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3485                 if (th == NULL)
3486                         break;
3487
3488                 ad->u.net.sport = th->source;
3489                 ad->u.net.dport = th->dest;
3490                 break;
3491         }
3492
3493         case IPPROTO_UDP: {
3494                 struct udphdr _udph, *uh;
3495
3496                 if (ntohs(ih->frag_off) & IP_OFFSET)
3497                         break;
3498
3499                 offset += ihlen;
3500                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3501                 if (uh == NULL)
3502                         break;
3503
3504                 ad->u.net.sport = uh->source;
3505                 ad->u.net.dport = uh->dest;
3506                 break;
3507         }
3508
3509         case IPPROTO_DCCP: {
3510                 struct dccp_hdr _dccph, *dh;
3511
3512                 if (ntohs(ih->frag_off) & IP_OFFSET)
3513                         break;
3514
3515                 offset += ihlen;
3516                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3517                 if (dh == NULL)
3518                         break;
3519
3520                 ad->u.net.sport = dh->dccph_sport;
3521                 ad->u.net.dport = dh->dccph_dport;
3522                 break;
3523         }
3524
3525         default:
3526                 break;
3527         }
3528 out:
3529         return ret;
3530 }
3531
3532 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3533
3534 /* Returns error only if unable to parse addresses */
3535 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3536                         struct common_audit_data *ad, u8 *proto)
3537 {
3538         u8 nexthdr;
3539         int ret = -EINVAL, offset;
3540         struct ipv6hdr _ipv6h, *ip6;
3541
3542         offset = skb_network_offset(skb);
3543         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3544         if (ip6 == NULL)
3545                 goto out;
3546
3547         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3548         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3549         ret = 0;
3550
3551         nexthdr = ip6->nexthdr;
3552         offset += sizeof(_ipv6h);
3553         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3554         if (offset < 0)
3555                 goto out;
3556
3557         if (proto)
3558                 *proto = nexthdr;
3559
3560         switch (nexthdr) {
3561         case IPPROTO_TCP: {
3562                 struct tcphdr _tcph, *th;
3563
3564                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3565                 if (th == NULL)
3566                         break;
3567
3568                 ad->u.net.sport = th->source;
3569                 ad->u.net.dport = th->dest;
3570                 break;
3571         }
3572
3573         case IPPROTO_UDP: {
3574                 struct udphdr _udph, *uh;
3575
3576                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3577                 if (uh == NULL)
3578                         break;
3579
3580                 ad->u.net.sport = uh->source;
3581                 ad->u.net.dport = uh->dest;
3582                 break;
3583         }
3584
3585         case IPPROTO_DCCP: {
3586                 struct dccp_hdr _dccph, *dh;
3587
3588                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3589                 if (dh == NULL)
3590                         break;
3591
3592                 ad->u.net.sport = dh->dccph_sport;
3593                 ad->u.net.dport = dh->dccph_dport;
3594                 break;
3595         }
3596
3597         /* includes fragments */
3598         default:
3599                 break;
3600         }
3601 out:
3602         return ret;
3603 }
3604
3605 #endif /* IPV6 */
3606
3607 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3608                              char **_addrp, int src, u8 *proto)
3609 {
3610         char *addrp;
3611         int ret;
3612
3613         switch (ad->u.net.family) {
3614         case PF_INET:
3615                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3616                 if (ret)
3617                         goto parse_error;
3618                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3619                                        &ad->u.net.v4info.daddr);
3620                 goto okay;
3621
3622 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3623         case PF_INET6:
3624                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3625                 if (ret)
3626                         goto parse_error;
3627                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3628                                        &ad->u.net.v6info.daddr);
3629                 goto okay;
3630 #endif  /* IPV6 */
3631         default:
3632                 addrp = NULL;
3633                 goto okay;
3634         }
3635
3636 parse_error:
3637         printk(KERN_WARNING
3638                "SELinux: failure in selinux_parse_skb(),"
3639                " unable to parse packet\n");
3640         return ret;
3641
3642 okay:
3643         if (_addrp)
3644                 *_addrp = addrp;
3645         return 0;
3646 }
3647
3648 /**
3649  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3650  * @skb: the packet
3651  * @family: protocol family
3652  * @sid: the packet's peer label SID
3653  *
3654  * Description:
3655  * Check the various different forms of network peer labeling and determine
3656  * the peer label/SID for the packet; most of the magic actually occurs in
3657  * the security server function security_net_peersid_cmp().  The function
3658  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3659  * or -EACCES if @sid is invalid due to inconsistencies with the different
3660  * peer labels.
3661  *
3662  */
3663 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3664 {
3665         int err;
3666         u32 xfrm_sid;
3667         u32 nlbl_sid;
3668         u32 nlbl_type;
3669
3670         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3671         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3672
3673         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3674         if (unlikely(err)) {
3675                 printk(KERN_WARNING
3676                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3677                        " unable to determine packet's peer label\n");
3678                 return -EACCES;
3679         }
3680
3681         return 0;
3682 }
3683
3684 /* socket security operations */
3685
3686 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3687                                  u16 secclass, u32 *socksid)
3688 {
3689         if (tsec->sockcreate_sid > SECSID_NULL) {
3690                 *socksid = tsec->sockcreate_sid;
3691                 return 0;
3692         }
3693
3694         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3695                                        socksid);
3696 }
3697
3698 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3699 {
3700         struct sk_security_struct *sksec = sk->sk_security;
3701         struct common_audit_data ad;
3702         u32 tsid = task_sid(task);
3703
3704         if (sksec->sid == SECINITSID_KERNEL)
3705                 return 0;
3706
3707         COMMON_AUDIT_DATA_INIT(&ad, NET);
3708         ad.u.net.sk = sk;
3709
3710         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3711 }
3712
3713 static int selinux_socket_create(int family, int type,
3714                                  int protocol, int kern)
3715 {
3716         const struct task_security_struct *tsec = current_security();
3717         u32 newsid;
3718         u16 secclass;
3719         int rc;
3720
3721         if (kern)
3722                 return 0;
3723
3724         secclass = socket_type_to_security_class(family, type, protocol);
3725         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3726         if (rc)
3727                 return rc;
3728
3729         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3730 }
3731
3732 static int selinux_socket_post_create(struct socket *sock, int family,
3733                                       int type, int protocol, int kern)
3734 {
3735         const struct task_security_struct *tsec = current_security();
3736         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3737         struct sk_security_struct *sksec;
3738         int err = 0;
3739
3740         isec->sclass = socket_type_to_security_class(family, type, protocol);
3741
3742         if (kern)
3743                 isec->sid = SECINITSID_KERNEL;
3744         else {
3745                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3746                 if (err)
3747                         return err;
3748         }
3749
3750         isec->initialized = 1;
3751
3752         if (sock->sk) {
3753                 sksec = sock->sk->sk_security;
3754                 sksec->sid = isec->sid;
3755                 sksec->sclass = isec->sclass;
3756                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3757         }
3758
3759         return err;
3760 }
3761
3762 /* Range of port numbers used to automatically bind.
3763    Need to determine whether we should perform a name_bind
3764    permission check between the socket and the port number. */
3765
3766 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3767 {
3768         struct sock *sk = sock->sk;
3769         u16 family;
3770         int err;
3771
3772         err = sock_has_perm(current, sk, SOCKET__BIND);
3773         if (err)
3774                 goto out;
3775
3776         /*
3777          * If PF_INET or PF_INET6, check name_bind permission for the port.
3778          * Multiple address binding for SCTP is not supported yet: we just
3779          * check the first address now.
3780          */
3781         family = sk->sk_family;
3782         if (family == PF_INET || family == PF_INET6) {
3783                 char *addrp;
3784                 struct sk_security_struct *sksec = sk->sk_security;
3785                 struct common_audit_data ad;
3786                 struct sockaddr_in *addr4 = NULL;
3787                 struct sockaddr_in6 *addr6 = NULL;
3788                 unsigned short snum;
3789                 u32 sid, node_perm;
3790
3791                 if (family == PF_INET) {
3792                         addr4 = (struct sockaddr_in *)address;
3793                         snum = ntohs(addr4->sin_port);
3794                         addrp = (char *)&addr4->sin_addr.s_addr;
3795                 } else {
3796                         addr6 = (struct sockaddr_in6 *)address;
3797                         snum = ntohs(addr6->sin6_port);
3798                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3799                 }
3800
3801                 if (snum) {
3802                         int low, high;
3803
3804                         inet_get_local_port_range(&low, &high);
3805
3806                         if (snum < max(PROT_SOCK, low) || snum > high) {
3807                                 err = sel_netport_sid(sk->sk_protocol,
3808                                                       snum, &sid);
3809                                 if (err)
3810                                         goto out;
3811                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3812                                 ad.u.net.sport = htons(snum);
3813                                 ad.u.net.family = family;
3814                                 err = avc_has_perm(sksec->sid, sid,
3815                                                    sksec->sclass,
3816                                                    SOCKET__NAME_BIND, &ad);
3817                                 if (err)
3818                                         goto out;
3819                         }
3820                 }
3821
3822                 switch (sksec->sclass) {
3823                 case SECCLASS_TCP_SOCKET:
3824                         node_perm = TCP_SOCKET__NODE_BIND;
3825                         break;
3826
3827                 case SECCLASS_UDP_SOCKET:
3828                         node_perm = UDP_SOCKET__NODE_BIND;
3829                         break;
3830
3831                 case SECCLASS_DCCP_SOCKET:
3832                         node_perm = DCCP_SOCKET__NODE_BIND;
3833                         break;
3834
3835                 default:
3836                         node_perm = RAWIP_SOCKET__NODE_BIND;
3837                         break;
3838                 }
3839
3840                 err = sel_netnode_sid(addrp, family, &sid);
3841                 if (err)
3842                         goto out;
3843
3844                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3845                 ad.u.net.sport = htons(snum);
3846                 ad.u.net.family = family;
3847
3848                 if (family == PF_INET)
3849                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3850                 else
3851                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3852
3853                 err = avc_has_perm(sksec->sid, sid,
3854                                    sksec->sclass, node_perm, &ad);
3855                 if (err)
3856                         goto out;
3857         }
3858 out:
3859         return err;
3860 }
3861
3862 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3863 {
3864         struct sock *sk = sock->sk;
3865         struct sk_security_struct *sksec = sk->sk_security;
3866         int err;
3867
3868         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3869         if (err)
3870                 return err;
3871
3872         /*
3873          * If a TCP or DCCP socket, check name_connect permission for the port.
3874          */
3875         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3876             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3877                 struct common_audit_data ad;
3878                 struct sockaddr_in *addr4 = NULL;
3879                 struct sockaddr_in6 *addr6 = NULL;
3880                 unsigned short snum;
3881                 u32 sid, perm;
3882
3883                 if (sk->sk_family == PF_INET) {
3884                         addr4 = (struct sockaddr_in *)address;
3885                         if (addrlen < sizeof(struct sockaddr_in))
3886                                 return -EINVAL;
3887                         snum = ntohs(addr4->sin_port);
3888                 } else {
3889                         addr6 = (struct sockaddr_in6 *)address;
3890                         if (addrlen < SIN6_LEN_RFC2133)
3891                                 return -EINVAL;
3892                         snum = ntohs(addr6->sin6_port);
3893                 }
3894
3895                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3896                 if (err)
3897                         goto out;
3898
3899                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3900                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3901
3902                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3903                 ad.u.net.dport = htons(snum);
3904                 ad.u.net.family = sk->sk_family;
3905                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3906                 if (err)
3907                         goto out;
3908         }
3909
3910         err = selinux_netlbl_socket_connect(sk, address);
3911
3912 out:
3913         return err;
3914 }
3915
3916 static int selinux_socket_listen(struct socket *sock, int backlog)
3917 {
3918         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3919 }
3920
3921 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3922 {
3923         int err;
3924         struct inode_security_struct *isec;
3925         struct inode_security_struct *newisec;
3926
3927         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3928         if (err)
3929                 return err;
3930
3931         newisec = SOCK_INODE(newsock)->i_security;
3932
3933         isec = SOCK_INODE(sock)->i_security;
3934         newisec->sclass = isec->sclass;
3935         newisec->sid = isec->sid;
3936         newisec->initialized = 1;
3937
3938         return 0;
3939 }
3940
3941 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3942                                   int size)
3943 {
3944         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3945 }
3946
3947 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3948                                   int size, int flags)
3949 {
3950         return sock_has_perm(current, sock->sk, SOCKET__READ);
3951 }
3952
3953 static int selinux_socket_getsockname(struct socket *sock)
3954 {
3955         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3956 }
3957
3958 static int selinux_socket_getpeername(struct socket *sock)
3959 {
3960         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3961 }
3962
3963 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3964 {
3965         int err;
3966
3967         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3968         if (err)
3969                 return err;
3970
3971         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3972 }
3973
3974 static int selinux_socket_getsockopt(struct socket *sock, int level,
3975                                      int optname)
3976 {
3977         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3978 }
3979
3980 static int selinux_socket_shutdown(struct socket *sock, int how)
3981 {
3982         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3983 }
3984
3985 static int selinux_socket_unix_stream_connect(struct sock *sock,
3986                                               struct sock *other,
3987                                               struct sock *newsk)
3988 {
3989         struct sk_security_struct *sksec_sock = sock->sk_security;
3990         struct sk_security_struct *sksec_other = other->sk_security;
3991         struct sk_security_struct *sksec_new = newsk->sk_security;
3992         struct common_audit_data ad;
3993         int err;
3994
3995         COMMON_AUDIT_DATA_INIT(&ad, NET);
3996         ad.u.net.sk = other;
3997
3998         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3999                            sksec_other->sclass,
4000                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4001         if (err)
4002                 return err;
4003
4004         /* server child socket */
4005         sksec_new->peer_sid = sksec_sock->sid;
4006         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4007                                     &sksec_new->sid);
4008         if (err)
4009                 return err;
4010
4011         /* connecting socket */
4012         sksec_sock->peer_sid = sksec_new->sid;
4013
4014         return 0;
4015 }
4016
4017 static int selinux_socket_unix_may_send(struct socket *sock,
4018                                         struct socket *other)
4019 {
4020         struct sk_security_struct *ssec = sock->sk->sk_security;
4021         struct sk_security_struct *osec = other->sk->sk_security;
4022         struct common_audit_data ad;
4023
4024         COMMON_AUDIT_DATA_INIT(&ad, NET);
4025         ad.u.net.sk = other->sk;
4026
4027         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4028                             &ad);
4029 }
4030
4031 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4032                                     u32 peer_sid,
4033                                     struct common_audit_data *ad)
4034 {
4035         int err;
4036         u32 if_sid;
4037         u32 node_sid;
4038
4039         err = sel_netif_sid(ifindex, &if_sid);
4040         if (err)
4041                 return err;
4042         err = avc_has_perm(peer_sid, if_sid,
4043                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4044         if (err)
4045                 return err;
4046
4047         err = sel_netnode_sid(addrp, family, &node_sid);
4048         if (err)
4049                 return err;
4050         return avc_has_perm(peer_sid, node_sid,
4051                             SECCLASS_NODE, NODE__RECVFROM, ad);
4052 }
4053
4054 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4055                                        u16 family)
4056 {
4057         int err = 0;
4058         struct sk_security_struct *sksec = sk->sk_security;
4059         u32 sk_sid = sksec->sid;
4060         struct common_audit_data ad;
4061         char *addrp;
4062
4063         COMMON_AUDIT_DATA_INIT(&ad, NET);
4064         ad.u.net.netif = skb->skb_iif;
4065         ad.u.net.family = family;
4066         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4067         if (err)
4068                 return err;
4069
4070         if (selinux_secmark_enabled()) {
4071                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4072                                    PACKET__RECV, &ad);
4073                 if (err)
4074                         return err;
4075         }
4076
4077         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4078         if (err)
4079                 return err;
4080         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4081
4082         return err;
4083 }
4084
4085 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4086 {
4087         int err;
4088         struct sk_security_struct *sksec = sk->sk_security;
4089         u16 family = sk->sk_family;
4090         u32 sk_sid = sksec->sid;
4091         struct common_audit_data ad;
4092         char *addrp;
4093         u8 secmark_active;
4094         u8 peerlbl_active;
4095
4096         if (family != PF_INET && family != PF_INET6)
4097                 return 0;
4098
4099         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4100         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4101                 family = PF_INET;
4102
4103         /* If any sort of compatibility mode is enabled then handoff processing
4104          * to the selinux_sock_rcv_skb_compat() function to deal with the
4105          * special handling.  We do this in an attempt to keep this function
4106          * as fast and as clean as possible. */
4107         if (!selinux_policycap_netpeer)
4108                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4109
4110         secmark_active = selinux_secmark_enabled();
4111         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4112         if (!secmark_active && !peerlbl_active)
4113                 return 0;
4114
4115         COMMON_AUDIT_DATA_INIT(&ad, NET);
4116         ad.u.net.netif = skb->skb_iif;
4117         ad.u.net.family = family;
4118         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4119         if (err)
4120                 return err;
4121
4122         if (peerlbl_active) {
4123                 u32 peer_sid;
4124
4125                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4126                 if (err)
4127                         return err;
4128                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4129                                                peer_sid, &ad);
4130                 if (err) {
4131                         selinux_netlbl_err(skb, err, 0);
4132                         return err;
4133                 }
4134                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4135                                    PEER__RECV, &ad);
4136                 if (err)
4137                         selinux_netlbl_err(skb, err, 0);
4138         }
4139
4140         if (secmark_active) {
4141                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4142                                    PACKET__RECV, &ad);
4143                 if (err)
4144                         return err;
4145         }
4146
4147         return err;
4148 }
4149
4150 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4151                                             int __user *optlen, unsigned len)
4152 {
4153         int err = 0;
4154         char *scontext;
4155         u32 scontext_len;
4156         struct sk_security_struct *sksec = sock->sk->sk_security;
4157         u32 peer_sid = SECSID_NULL;
4158
4159         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4160             sksec->sclass == SECCLASS_TCP_SOCKET)
4161                 peer_sid = sksec->peer_sid;
4162         if (peer_sid == SECSID_NULL)
4163                 return -ENOPROTOOPT;
4164
4165         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4166         if (err)
4167                 return err;
4168
4169         if (scontext_len > len) {
4170                 err = -ERANGE;
4171                 goto out_len;
4172         }
4173
4174         if (copy_to_user(optval, scontext, scontext_len))
4175                 err = -EFAULT;
4176
4177 out_len:
4178         if (put_user(scontext_len, optlen))
4179                 err = -EFAULT;
4180         kfree(scontext);
4181         return err;
4182 }
4183
4184 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4185 {
4186         u32 peer_secid = SECSID_NULL;
4187         u16 family;
4188
4189         if (skb && skb->protocol == htons(ETH_P_IP))
4190                 family = PF_INET;
4191         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4192                 family = PF_INET6;
4193         else if (sock)
4194                 family = sock->sk->sk_family;
4195         else
4196                 goto out;
4197
4198         if (sock && family == PF_UNIX)
4199                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4200         else if (skb)
4201                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4202
4203 out:
4204         *secid = peer_secid;
4205         if (peer_secid == SECSID_NULL)
4206                 return -EINVAL;
4207         return 0;
4208 }
4209
4210 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4211 {
4212         struct sk_security_struct *sksec;
4213
4214         sksec = kzalloc(sizeof(*sksec), priority);
4215         if (!sksec)
4216                 return -ENOMEM;
4217
4218         sksec->peer_sid = SECINITSID_UNLABELED;
4219         sksec->sid = SECINITSID_UNLABELED;
4220         selinux_netlbl_sk_security_reset(sksec);
4221         sk->sk_security = sksec;
4222
4223         return 0;
4224 }
4225
4226 static void selinux_sk_free_security(struct sock *sk)
4227 {
4228         struct sk_security_struct *sksec = sk->sk_security;
4229
4230         sk->sk_security = NULL;
4231         selinux_netlbl_sk_security_free(sksec);
4232         kfree(sksec);
4233 }
4234
4235 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4236 {
4237         struct sk_security_struct *sksec = sk->sk_security;
4238         struct sk_security_struct *newsksec = newsk->sk_security;
4239
4240         newsksec->sid = sksec->sid;
4241         newsksec->peer_sid = sksec->peer_sid;
4242         newsksec->sclass = sksec->sclass;
4243
4244         selinux_netlbl_sk_security_reset(newsksec);
4245 }
4246
4247 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4248 {
4249         if (!sk)
4250                 *secid = SECINITSID_ANY_SOCKET;
4251         else {
4252                 struct sk_security_struct *sksec = sk->sk_security;
4253
4254                 *secid = sksec->sid;
4255         }
4256 }
4257
4258 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4259 {
4260         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4261         struct sk_security_struct *sksec = sk->sk_security;
4262
4263         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4264             sk->sk_family == PF_UNIX)
4265                 isec->sid = sksec->sid;
4266         sksec->sclass = isec->sclass;
4267 }
4268
4269 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4270                                      struct request_sock *req)
4271 {
4272         struct sk_security_struct *sksec = sk->sk_security;
4273         int err;
4274         u16 family = sk->sk_family;
4275         u32 newsid;
4276         u32 peersid;
4277
4278         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4279         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4280                 family = PF_INET;
4281
4282         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4283         if (err)
4284                 return err;
4285         if (peersid == SECSID_NULL) {
4286                 req->secid = sksec->sid;
4287                 req->peer_secid = SECSID_NULL;
4288         } else {
4289                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4290                 if (err)
4291                         return err;
4292                 req->secid = newsid;
4293                 req->peer_secid = peersid;
4294         }
4295
4296         return selinux_netlbl_inet_conn_request(req, family);
4297 }
4298
4299 static void selinux_inet_csk_clone(struct sock *newsk,
4300                                    const struct request_sock *req)
4301 {
4302         struct sk_security_struct *newsksec = newsk->sk_security;
4303
4304         newsksec->sid = req->secid;
4305         newsksec->peer_sid = req->peer_secid;
4306         /* NOTE: Ideally, we should also get the isec->sid for the
4307            new socket in sync, but we don't have the isec available yet.
4308            So we will wait until sock_graft to do it, by which
4309            time it will have been created and available. */
4310
4311         /* We don't need to take any sort of lock here as we are the only
4312          * thread with access to newsksec */
4313         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4314 }
4315
4316 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4317 {
4318         u16 family = sk->sk_family;
4319         struct sk_security_struct *sksec = sk->sk_security;
4320
4321         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4322         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4323                 family = PF_INET;
4324
4325         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4326 }
4327
4328 static int selinux_secmark_relabel_packet(u32 sid)
4329 {
4330         const struct task_security_struct *__tsec;
4331         u32 tsid;
4332
4333         __tsec = current_security();
4334         tsid = __tsec->sid;
4335
4336         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4337 }
4338
4339 static void selinux_secmark_refcount_inc(void)
4340 {
4341         atomic_inc(&selinux_secmark_refcount);
4342 }
4343
4344 static void selinux_secmark_refcount_dec(void)
4345 {
4346         atomic_dec(&selinux_secmark_refcount);
4347 }
4348
4349 static void selinux_req_classify_flow(const struct request_sock *req,
4350                                       struct flowi *fl)
4351 {
4352         fl->flowi_secid = req->secid;
4353 }
4354
4355 static int selinux_tun_dev_create(void)
4356 {
4357         u32 sid = current_sid();
4358
4359         /* we aren't taking into account the "sockcreate" SID since the socket
4360          * that is being created here is not a socket in the traditional sense,
4361          * instead it is a private sock, accessible only to the kernel, and
4362          * representing a wide range of network traffic spanning multiple
4363          * connections unlike traditional sockets - check the TUN driver to
4364          * get a better understanding of why this socket is special */
4365
4366         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4367                             NULL);
4368 }
4369
4370 static void selinux_tun_dev_post_create(struct sock *sk)
4371 {
4372         struct sk_security_struct *sksec = sk->sk_security;
4373
4374         /* we don't currently perform any NetLabel based labeling here and it
4375          * isn't clear that we would want to do so anyway; while we could apply
4376          * labeling without the support of the TUN user the resulting labeled
4377          * traffic from the other end of the connection would almost certainly
4378          * cause confusion to the TUN user that had no idea network labeling
4379          * protocols were being used */
4380
4381         /* see the comments in selinux_tun_dev_create() about why we don't use
4382          * the sockcreate SID here */
4383
4384         sksec->sid = current_sid();
4385         sksec->sclass = SECCLASS_TUN_SOCKET;
4386 }
4387
4388 static int selinux_tun_dev_attach(struct sock *sk)
4389 {
4390         struct sk_security_struct *sksec = sk->sk_security;
4391         u32 sid = current_sid();
4392         int err;
4393
4394         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4395                            TUN_SOCKET__RELABELFROM, NULL);
4396         if (err)
4397                 return err;
4398         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4399                            TUN_SOCKET__RELABELTO, NULL);
4400         if (err)
4401                 return err;
4402
4403         sksec->sid = sid;
4404
4405         return 0;
4406 }
4407
4408 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4409 {
4410         int err = 0;
4411         u32 perm;
4412         struct nlmsghdr *nlh;
4413         struct sk_security_struct *sksec = sk->sk_security;
4414
4415         if (skb->len < NLMSG_SPACE(0)) {
4416                 err = -EINVAL;
4417                 goto out;
4418         }
4419         nlh = nlmsg_hdr(skb);
4420
4421         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4422         if (err) {
4423                 if (err == -EINVAL) {
4424                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4425                                   "SELinux:  unrecognized netlink message"
4426                                   " type=%hu for sclass=%hu\n",
4427                                   nlh->nlmsg_type, sksec->sclass);
4428                         if (!selinux_enforcing || security_get_allow_unknown())
4429                                 err = 0;
4430                 }
4431
4432                 /* Ignore */
4433                 if (err == -ENOENT)
4434                         err = 0;
4435                 goto out;
4436         }
4437
4438         err = sock_has_perm(current, sk, perm);
4439 out:
4440         return err;
4441 }
4442
4443 #ifdef CONFIG_NETFILTER
4444
4445 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4446                                        u16 family)
4447 {
4448         int err;
4449         char *addrp;
4450         u32 peer_sid;
4451         struct common_audit_data ad;
4452         u8 secmark_active;
4453         u8 netlbl_active;
4454         u8 peerlbl_active;
4455
4456         if (!selinux_policycap_netpeer)
4457                 return NF_ACCEPT;
4458
4459         secmark_active = selinux_secmark_enabled();
4460         netlbl_active = netlbl_enabled();
4461         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4462         if (!secmark_active && !peerlbl_active)
4463                 return NF_ACCEPT;
4464
4465         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4466                 return NF_DROP;
4467
4468         COMMON_AUDIT_DATA_INIT(&ad, NET);
4469         ad.u.net.netif = ifindex;
4470         ad.u.net.family = family;
4471         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4472                 return NF_DROP;
4473
4474         if (peerlbl_active) {
4475                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4476                                                peer_sid, &ad);
4477                 if (err) {
4478                         selinux_netlbl_err(skb, err, 1);
4479                         return NF_DROP;
4480                 }
4481         }
4482
4483         if (secmark_active)
4484                 if (avc_has_perm(peer_sid, skb->secmark,
4485                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4486                         return NF_DROP;
4487
4488         if (netlbl_active)
4489                 /* we do this in the FORWARD path and not the POST_ROUTING
4490                  * path because we want to make sure we apply the necessary
4491                  * labeling before IPsec is applied so we can leverage AH
4492                  * protection */
4493                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4494                         return NF_DROP;
4495
4496         return NF_ACCEPT;
4497 }
4498
4499 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4500                                          struct sk_buff *skb,
4501                                          const struct net_device *in,
4502                                          const struct net_device *out,
4503                                          int (*okfn)(struct sk_buff *))
4504 {
4505         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4506 }
4507
4508 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4509 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4510                                          struct sk_buff *skb,
4511                                          const struct net_device *in,
4512                                          const struct net_device *out,
4513                                          int (*okfn)(struct sk_buff *))
4514 {
4515         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4516 }
4517 #endif  /* IPV6 */
4518
4519 static unsigned int selinux_ip_output(struct sk_buff *skb,
4520                                       u16 family)
4521 {
4522         u32 sid;
4523
4524         if (!netlbl_enabled())
4525                 return NF_ACCEPT;
4526
4527         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4528          * because we want to make sure we apply the necessary labeling
4529          * before IPsec is applied so we can leverage AH protection */
4530         if (skb->sk) {
4531                 struct sk_security_struct *sksec = skb->sk->sk_security;
4532                 sid = sksec->sid;
4533         } else
4534                 sid = SECINITSID_KERNEL;
4535         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4536                 return NF_DROP;
4537
4538         return NF_ACCEPT;
4539 }
4540
4541 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4542                                         struct sk_buff *skb,
4543                                         const struct net_device *in,
4544                                         const struct net_device *out,
4545                                         int (*okfn)(struct sk_buff *))
4546 {
4547         return selinux_ip_output(skb, PF_INET);
4548 }
4549
4550 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4551                                                 int ifindex,
4552                                                 u16 family)
4553 {
4554         struct sock *sk = skb->sk;
4555         struct sk_security_struct *sksec;
4556         struct common_audit_data ad;
4557         char *addrp;
4558         u8 proto;
4559
4560         if (sk == NULL)
4561                 return NF_ACCEPT;
4562         sksec = sk->sk_security;
4563
4564         COMMON_AUDIT_DATA_INIT(&ad, NET);
4565         ad.u.net.netif = ifindex;
4566         ad.u.net.family = family;
4567         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4568                 return NF_DROP;
4569
4570         if (selinux_secmark_enabled())
4571                 if (avc_has_perm(sksec->sid, skb->secmark,
4572                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4573                         return NF_DROP_ERR(-ECONNREFUSED);
4574
4575         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4576                 return NF_DROP_ERR(-ECONNREFUSED);
4577
4578         return NF_ACCEPT;
4579 }
4580
4581 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4582                                          u16 family)
4583 {
4584         u32 secmark_perm;
4585         u32 peer_sid;
4586         struct sock *sk;
4587         struct common_audit_data ad;
4588         char *addrp;
4589         u8 secmark_active;
4590         u8 peerlbl_active;
4591
4592         /* If any sort of compatibility mode is enabled then handoff processing
4593          * to the selinux_ip_postroute_compat() function to deal with the
4594          * special handling.  We do this in an attempt to keep this function
4595          * as fast and as clean as possible. */
4596         if (!selinux_policycap_netpeer)
4597                 return selinux_ip_postroute_compat(skb, ifindex, family);
4598 #ifdef CONFIG_XFRM
4599         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4600          * packet transformation so allow the packet to pass without any checks
4601          * since we'll have another chance to perform access control checks
4602          * when the packet is on it's final way out.
4603          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4604          *       is NULL, in this case go ahead and apply access control. */
4605         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4606                 return NF_ACCEPT;
4607 #endif
4608         secmark_active = selinux_secmark_enabled();
4609         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4610         if (!secmark_active && !peerlbl_active)
4611                 return NF_ACCEPT;
4612
4613         /* if the packet is being forwarded then get the peer label from the
4614          * packet itself; otherwise check to see if it is from a local
4615          * application or the kernel, if from an application get the peer label
4616          * from the sending socket, otherwise use the kernel's sid */
4617         sk = skb->sk;
4618         if (sk == NULL) {
4619                 if (skb->skb_iif) {
4620                         secmark_perm = PACKET__FORWARD_OUT;
4621                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4622                                 return NF_DROP;
4623                 } else {
4624                         secmark_perm = PACKET__SEND;
4625                         peer_sid = SECINITSID_KERNEL;
4626                 }
4627         } else {
4628                 struct sk_security_struct *sksec = sk->sk_security;
4629                 peer_sid = sksec->sid;
4630                 secmark_perm = PACKET__SEND;
4631         }
4632
4633         COMMON_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_ERR(-ECONNREFUSED);
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_ERR(-ECONNREFUSED);
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_ERR(-ECONNREFUSED);
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 = cap_netlink_send(sk, skb);
4691         if (err)
4692                 return err;
4693
4694         return selinux_nlmsg_perm(sk, skb);
4695 }
4696
4697 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4698 {
4699         int err;
4700         struct common_audit_data ad;
4701         u32 sid;
4702
4703         err = cap_netlink_recv(skb, capability);
4704         if (err)
4705                 return err;
4706
4707         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4708         ad.u.cap = capability;
4709
4710         security_task_getsecid(current, &sid);
4711         return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4712                             CAP_TO_MASK(capability), &ad);
4713 }
4714
4715 static int ipc_alloc_security(struct task_struct *task,
4716                               struct kern_ipc_perm *perm,
4717                               u16 sclass)
4718 {
4719         struct ipc_security_struct *isec;
4720         u32 sid;
4721
4722         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4723         if (!isec)
4724                 return -ENOMEM;
4725
4726         sid = task_sid(task);
4727         isec->sclass = sclass;
4728         isec->sid = 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 ipc_security_struct *isec;
4767         struct common_audit_data ad;
4768         u32 sid = current_sid();
4769
4770         isec = ipc_perms->security;
4771
4772         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4773         ad.u.ipc_id = ipc_perms->key;
4774
4775         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4776 }
4777
4778 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4779 {
4780         return msg_msg_alloc_security(msg);
4781 }
4782
4783 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4784 {
4785         msg_msg_free_security(msg);
4786 }
4787
4788 /* message queue security operations */
4789 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4790 {
4791         struct ipc_security_struct *isec;
4792         struct common_audit_data ad;
4793         u32 sid = current_sid();
4794         int rc;
4795
4796         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4797         if (rc)
4798                 return rc;
4799
4800         isec = msq->q_perm.security;
4801
4802         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4803         ad.u.ipc_id = msq->q_perm.key;
4804
4805         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4806                           MSGQ__CREATE, &ad);
4807         if (rc) {
4808                 ipc_free_security(&msq->q_perm);
4809                 return rc;
4810         }
4811         return 0;
4812 }
4813
4814 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4815 {
4816         ipc_free_security(&msq->q_perm);
4817 }
4818
4819 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4820 {
4821         struct ipc_security_struct *isec;
4822         struct common_audit_data ad;
4823         u32 sid = current_sid();
4824
4825         isec = msq->q_perm.security;
4826
4827         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4828         ad.u.ipc_id = msq->q_perm.key;
4829
4830         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4831                             MSGQ__ASSOCIATE, &ad);
4832 }
4833
4834 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4835 {
4836         int err;
4837         int perms;
4838
4839         switch (cmd) {
4840         case IPC_INFO:
4841         case MSG_INFO:
4842                 /* No specific object, just general system-wide information. */
4843                 return task_has_system(current, SYSTEM__IPC_INFO);
4844         case IPC_STAT:
4845         case MSG_STAT:
4846                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4847                 break;
4848         case IPC_SET:
4849                 perms = MSGQ__SETATTR;
4850                 break;
4851         case IPC_RMID:
4852                 perms = MSGQ__DESTROY;
4853                 break;
4854         default:
4855                 return 0;
4856         }
4857
4858         err = ipc_has_perm(&msq->q_perm, perms);
4859         return err;
4860 }
4861
4862 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4863 {
4864         struct ipc_security_struct *isec;
4865         struct msg_security_struct *msec;
4866         struct common_audit_data ad;
4867         u32 sid = current_sid();
4868         int rc;
4869
4870         isec = msq->q_perm.security;
4871         msec = msg->security;
4872
4873         /*
4874          * First time through, need to assign label to the message
4875          */
4876         if (msec->sid == SECINITSID_UNLABELED) {
4877                 /*
4878                  * Compute new sid based on current process and
4879                  * message queue this message will be stored in
4880                  */
4881                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4882                                              NULL, &msec->sid);
4883                 if (rc)
4884                         return rc;
4885         }
4886
4887         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4888         ad.u.ipc_id = msq->q_perm.key;
4889
4890         /* Can this process write to the queue? */
4891         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4892                           MSGQ__WRITE, &ad);
4893         if (!rc)
4894                 /* Can this process send the message */
4895                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4896                                   MSG__SEND, &ad);
4897         if (!rc)
4898                 /* Can the message be put in the queue? */
4899                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4900                                   MSGQ__ENQUEUE, &ad);
4901
4902         return rc;
4903 }
4904
4905 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4906                                     struct task_struct *target,
4907                                     long type, int mode)
4908 {
4909         struct ipc_security_struct *isec;
4910         struct msg_security_struct *msec;
4911         struct common_audit_data ad;
4912         u32 sid = task_sid(target);
4913         int rc;
4914
4915         isec = msq->q_perm.security;
4916         msec = msg->security;
4917
4918         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4919         ad.u.ipc_id = msq->q_perm.key;
4920
4921         rc = avc_has_perm(sid, isec->sid,
4922                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4923         if (!rc)
4924                 rc = avc_has_perm(sid, msec->sid,
4925                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4926         return rc;
4927 }
4928
4929 /* Shared Memory security operations */
4930 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4931 {
4932         struct ipc_security_struct *isec;
4933         struct common_audit_data ad;
4934         u32 sid = current_sid();
4935         int rc;
4936
4937         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4938         if (rc)
4939                 return rc;
4940
4941         isec = shp->shm_perm.security;
4942
4943         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4944         ad.u.ipc_id = shp->shm_perm.key;
4945
4946         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4947                           SHM__CREATE, &ad);
4948         if (rc) {
4949                 ipc_free_security(&shp->shm_perm);
4950                 return rc;
4951         }
4952         return 0;
4953 }
4954
4955 static void selinux_shm_free_security(struct shmid_kernel *shp)
4956 {
4957         ipc_free_security(&shp->shm_perm);
4958 }
4959
4960 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4961 {
4962         struct ipc_security_struct *isec;
4963         struct common_audit_data ad;
4964         u32 sid = current_sid();
4965
4966         isec = shp->shm_perm.security;
4967
4968         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4969         ad.u.ipc_id = shp->shm_perm.key;
4970
4971         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4972                             SHM__ASSOCIATE, &ad);
4973 }
4974
4975 /* Note, at this point, shp is locked down */
4976 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4977 {
4978         int perms;
4979         int err;
4980
4981         switch (cmd) {
4982         case IPC_INFO:
4983         case SHM_INFO:
4984                 /* No specific object, just general system-wide information. */
4985                 return task_has_system(current, SYSTEM__IPC_INFO);
4986         case IPC_STAT:
4987         case SHM_STAT:
4988                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4989                 break;
4990         case IPC_SET:
4991                 perms = SHM__SETATTR;
4992                 break;
4993         case SHM_LOCK:
4994         case SHM_UNLOCK:
4995                 perms = SHM__LOCK;
4996                 break;
4997         case IPC_RMID:
4998                 perms = SHM__DESTROY;
4999                 break;
5000         default:
5001                 return 0;
5002         }
5003
5004         err = ipc_has_perm(&shp->shm_perm, perms);
5005         return err;
5006 }
5007
5008 static int selinux_shm_shmat(struct shmid_kernel *shp,
5009                              char __user *shmaddr, int shmflg)
5010 {
5011         u32 perms;
5012
5013         if (shmflg & SHM_RDONLY)
5014                 perms = SHM__READ;
5015         else
5016                 perms = SHM__READ | SHM__WRITE;
5017
5018         return ipc_has_perm(&shp->shm_perm, perms);
5019 }
5020
5021 /* Semaphore security operations */
5022 static int selinux_sem_alloc_security(struct sem_array *sma)
5023 {
5024         struct ipc_security_struct *isec;
5025         struct common_audit_data ad;
5026         u32 sid = current_sid();
5027         int rc;
5028
5029         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5030         if (rc)
5031                 return rc;
5032
5033         isec = sma->sem_perm.security;
5034
5035         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5036         ad.u.ipc_id = sma->sem_perm.key;
5037
5038         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5039                           SEM__CREATE, &ad);
5040         if (rc) {
5041                 ipc_free_security(&sma->sem_perm);
5042                 return rc;
5043         }
5044         return 0;
5045 }
5046
5047 static void selinux_sem_free_security(struct sem_array *sma)
5048 {
5049         ipc_free_security(&sma->sem_perm);
5050 }
5051
5052 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5053 {
5054         struct ipc_security_struct *isec;
5055         struct common_audit_data ad;
5056         u32 sid = current_sid();
5057
5058         isec = sma->sem_perm.security;
5059
5060         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5061         ad.u.ipc_id = sma->sem_perm.key;
5062
5063         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5064                             SEM__ASSOCIATE, &ad);
5065 }
5066
5067 /* Note, at this point, sma is locked down */
5068 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5069 {
5070         int err;
5071         u32 perms;
5072
5073         switch (cmd) {
5074         case IPC_INFO:
5075         case SEM_INFO:
5076                 /* No specific object, just general system-wide information. */
5077                 return task_has_system(current, SYSTEM__IPC_INFO);
5078         case GETPID:
5079         case GETNCNT:
5080         case GETZCNT:
5081                 perms = SEM__GETATTR;
5082                 break;
5083         case GETVAL:
5084         case GETALL:
5085                 perms = SEM__READ;
5086                 break;
5087         case SETVAL:
5088         case SETALL:
5089                 perms = SEM__WRITE;
5090                 break;
5091         case IPC_RMID:
5092                 perms = SEM__DESTROY;
5093                 break;
5094         case IPC_SET:
5095                 perms = SEM__SETATTR;
5096                 break;
5097         case IPC_STAT:
5098         case SEM_STAT:
5099                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5100                 break;
5101         default:
5102                 return 0;
5103         }
5104
5105         err = ipc_has_perm(&sma->sem_perm, perms);
5106         return err;
5107 }
5108
5109 static int selinux_sem_semop(struct sem_array *sma,
5110                              struct sembuf *sops, unsigned nsops, int alter)
5111 {
5112         u32 perms;
5113
5114         if (alter)
5115                 perms = SEM__READ | SEM__WRITE;
5116         else
5117                 perms = SEM__READ;
5118
5119         return ipc_has_perm(&sma->sem_perm, perms);
5120 }
5121
5122 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5123 {
5124         u32 av = 0;
5125
5126         av = 0;
5127         if (flag & S_IRUGO)
5128                 av |= IPC__UNIX_READ;
5129         if (flag & S_IWUGO)
5130                 av |= IPC__UNIX_WRITE;
5131
5132         if (av == 0)
5133                 return 0;
5134
5135         return ipc_has_perm(ipcp, av);
5136 }
5137
5138 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5139 {
5140         struct ipc_security_struct *isec = ipcp->security;
5141         *secid = isec->sid;
5142 }
5143
5144 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5145 {
5146         if (inode)
5147                 inode_doinit_with_dentry(inode, dentry);
5148 }
5149
5150 static int selinux_getprocattr(struct task_struct *p,
5151                                char *name, char **value)
5152 {
5153         const struct task_security_struct *__tsec;
5154         u32 sid;
5155         int error;
5156         unsigned len;
5157
5158         if (current != p) {
5159                 error = current_has_perm(p, PROCESS__GETATTR);
5160                 if (error)
5161                         return error;
5162         }
5163
5164         rcu_read_lock();
5165         __tsec = __task_cred(p)->security;
5166
5167         if (!strcmp(name, "current"))
5168                 sid = __tsec->sid;
5169         else if (!strcmp(name, "prev"))
5170                 sid = __tsec->osid;
5171         else if (!strcmp(name, "exec"))
5172                 sid = __tsec->exec_sid;
5173         else if (!strcmp(name, "fscreate"))
5174                 sid = __tsec->create_sid;
5175         else if (!strcmp(name, "keycreate"))
5176                 sid = __tsec->keycreate_sid;
5177         else if (!strcmp(name, "sockcreate"))
5178                 sid = __tsec->sockcreate_sid;
5179         else
5180                 goto invalid;
5181         rcu_read_unlock();
5182
5183         if (!sid)
5184                 return 0;
5185
5186         error = security_sid_to_context(sid, value, &len);
5187         if (error)
5188                 return error;
5189         return len;
5190
5191 invalid:
5192         rcu_read_unlock();
5193         return -EINVAL;
5194 }
5195
5196 static int selinux_setprocattr(struct task_struct *p,
5197                                char *name, void *value, size_t size)
5198 {
5199         struct task_security_struct *tsec;
5200         struct task_struct *tracer;
5201         struct cred *new;
5202         u32 sid = 0, ptsid;
5203         int error;
5204         char *str = value;
5205
5206         if (current != p) {
5207                 /* SELinux only allows a process to change its own
5208                    security attributes. */
5209                 return -EACCES;
5210         }
5211
5212         /*
5213          * Basic control over ability to set these attributes at all.
5214          * current == p, but we'll pass them separately in case the
5215          * above restriction is ever removed.
5216          */
5217         if (!strcmp(name, "exec"))
5218                 error = current_has_perm(p, PROCESS__SETEXEC);
5219         else if (!strcmp(name, "fscreate"))
5220                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5221         else if (!strcmp(name, "keycreate"))
5222                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5223         else if (!strcmp(name, "sockcreate"))
5224                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5225         else if (!strcmp(name, "current"))
5226                 error = current_has_perm(p, PROCESS__SETCURRENT);
5227         else
5228                 error = -EINVAL;
5229         if (error)
5230                 return error;
5231
5232         /* Obtain a SID for the context, if one was specified. */
5233         if (size && str[1] && str[1] != '\n') {
5234                 if (str[size-1] == '\n') {
5235                         str[size-1] = 0;
5236                         size--;
5237                 }
5238                 error = security_context_to_sid(value, size, &sid);
5239                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5240                         if (!capable(CAP_MAC_ADMIN))
5241                                 return error;
5242                         error = security_context_to_sid_force(value, size,
5243                                                               &sid);
5244                 }
5245                 if (error)
5246                         return error;
5247         }
5248
5249         new = prepare_creds();
5250         if (!new)
5251                 return -ENOMEM;
5252
5253         /* Permission checking based on the specified context is
5254            performed during the actual operation (execve,
5255            open/mkdir/...), when we know the full context of the
5256            operation.  See selinux_bprm_set_creds for the execve
5257            checks and may_create for the file creation checks. The
5258            operation will then fail if the context is not permitted. */
5259         tsec = new->security;
5260         if (!strcmp(name, "exec")) {
5261                 tsec->exec_sid = sid;
5262         } else if (!strcmp(name, "fscreate")) {
5263                 tsec->create_sid = sid;
5264         } else if (!strcmp(name, "keycreate")) {
5265                 error = may_create_key(sid, p);
5266                 if (error)
5267                         goto abort_change;
5268                 tsec->keycreate_sid = sid;
5269         } else if (!strcmp(name, "sockcreate")) {
5270                 tsec->sockcreate_sid = sid;
5271         } else if (!strcmp(name, "current")) {
5272                 error = -EINVAL;
5273                 if (sid == 0)
5274                         goto abort_change;
5275
5276                 /* Only allow single threaded processes to change context */
5277                 error = -EPERM;
5278                 if (!current_is_single_threaded()) {
5279                         error = security_bounded_transition(tsec->sid, sid);
5280                         if (error)
5281                                 goto abort_change;
5282                 }
5283
5284                 /* Check permissions for the transition. */
5285                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5286                                      PROCESS__DYNTRANSITION, NULL);
5287                 if (error)
5288                         goto abort_change;
5289
5290                 /* Check for ptracing, and update the task SID if ok.
5291                    Otherwise, leave SID unchanged and fail. */
5292                 ptsid = 0;
5293                 task_lock(p);
5294                 tracer = tracehook_tracer_task(p);
5295                 if (tracer)
5296                         ptsid = task_sid(tracer);
5297                 task_unlock(p);
5298
5299                 if (tracer) {
5300                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5301                                              PROCESS__PTRACE, NULL);
5302                         if (error)
5303                                 goto abort_change;
5304                 }
5305
5306                 tsec->sid = sid;
5307         } else {
5308                 error = -EINVAL;
5309                 goto abort_change;
5310         }
5311
5312         commit_creds(new);
5313         return size;
5314
5315 abort_change:
5316         abort_creds(new);
5317         return error;
5318 }
5319
5320 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5321 {
5322         return security_sid_to_context(secid, secdata, seclen);
5323 }
5324
5325 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5326 {
5327         return security_context_to_sid(secdata, seclen, secid);
5328 }
5329
5330 static void selinux_release_secctx(char *secdata, u32 seclen)
5331 {
5332         kfree(secdata);
5333 }
5334
5335 /*
5336  *      called with inode->i_mutex locked
5337  */
5338 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5339 {
5340         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5341 }
5342
5343 /*
5344  *      called with inode->i_mutex locked
5345  */
5346 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5347 {
5348         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5349 }
5350
5351 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5352 {
5353         int len = 0;
5354         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5355                                                 ctx, true);
5356         if (len < 0)
5357                 return len;
5358         *ctxlen = len;
5359         return 0;
5360 }
5361 #ifdef CONFIG_KEYS
5362
5363 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5364                              unsigned long flags)
5365 {
5366         const struct task_security_struct *tsec;
5367         struct key_security_struct *ksec;
5368
5369         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5370         if (!ksec)
5371                 return -ENOMEM;
5372
5373         tsec = cred->security;
5374         if (tsec->keycreate_sid)
5375                 ksec->sid = tsec->keycreate_sid;
5376         else
5377                 ksec->sid = tsec->sid;
5378
5379         k->security = ksec;
5380         return 0;
5381 }
5382
5383 static void selinux_key_free(struct key *k)
5384 {
5385         struct key_security_struct *ksec = k->security;
5386
5387         k->security = NULL;
5388         kfree(ksec);
5389 }
5390
5391 static int selinux_key_permission(key_ref_t key_ref,
5392                                   const struct cred *cred,
5393                                   key_perm_t perm)
5394 {
5395         struct key *key;
5396         struct key_security_struct *ksec;
5397         u32 sid;
5398
5399         /* if no specific permissions are requested, we skip the
5400            permission check. No serious, additional covert channels
5401            appear to be created. */
5402         if (perm == 0)
5403                 return 0;
5404
5405         sid = cred_sid(cred);
5406
5407         key = key_ref_to_ptr(key_ref);
5408         ksec = key->security;
5409
5410         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5411 }
5412
5413 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5414 {
5415         struct key_security_struct *ksec = key->security;
5416         char *context = NULL;
5417         unsigned len;
5418         int rc;
5419
5420         rc = security_sid_to_context(ksec->sid, &context, &len);
5421         if (!rc)
5422                 rc = len;
5423         *_buffer = context;
5424         return rc;
5425 }
5426
5427 #endif
5428
5429 static struct security_operations selinux_ops = {
5430         .name =                         "selinux",
5431
5432         .ptrace_access_check =          selinux_ptrace_access_check,
5433         .ptrace_traceme =               selinux_ptrace_traceme,
5434         .capget =                       selinux_capget,
5435         .capset =                       selinux_capset,
5436         .capable =                      selinux_capable,
5437         .quotactl =                     selinux_quotactl,
5438         .quota_on =                     selinux_quota_on,
5439         .syslog =                       selinux_syslog,
5440         .vm_enough_memory =             selinux_vm_enough_memory,
5441
5442         .netlink_send =                 selinux_netlink_send,
5443         .netlink_recv =                 selinux_netlink_recv,
5444
5445         .bprm_set_creds =               selinux_bprm_set_creds,
5446         .bprm_committing_creds =        selinux_bprm_committing_creds,
5447         .bprm_committed_creds =         selinux_bprm_committed_creds,
5448         .bprm_secureexec =              selinux_bprm_secureexec,
5449
5450         .sb_alloc_security =            selinux_sb_alloc_security,
5451         .sb_free_security =             selinux_sb_free_security,
5452         .sb_copy_data =                 selinux_sb_copy_data,
5453         .sb_remount =                   selinux_sb_remount,
5454         .sb_kern_mount =                selinux_sb_kern_mount,
5455         .sb_show_options =              selinux_sb_show_options,
5456         .sb_statfs =                    selinux_sb_statfs,
5457         .sb_mount =                     selinux_mount,
5458         .sb_umount =                    selinux_umount,
5459         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5460         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5461         .sb_parse_opts_str =            selinux_parse_opts_str,
5462
5463
5464         .inode_alloc_security =         selinux_inode_alloc_security,
5465         .inode_free_security =          selinux_inode_free_security,
5466         .inode_init_security =          selinux_inode_init_security,
5467         .inode_create =                 selinux_inode_create,
5468         .inode_link =                   selinux_inode_link,
5469         .inode_unlink =                 selinux_inode_unlink,
5470         .inode_symlink =                selinux_inode_symlink,
5471         .inode_mkdir =                  selinux_inode_mkdir,
5472         .inode_rmdir =                  selinux_inode_rmdir,
5473         .inode_mknod =                  selinux_inode_mknod,
5474         .inode_rename =                 selinux_inode_rename,
5475         .inode_readlink =               selinux_inode_readlink,
5476         .inode_follow_link =            selinux_inode_follow_link,
5477         .inode_permission =             selinux_inode_permission,
5478         .inode_setattr =                selinux_inode_setattr,
5479         .inode_getattr =                selinux_inode_getattr,
5480         .inode_setxattr =               selinux_inode_setxattr,
5481         .inode_post_setxattr =          selinux_inode_post_setxattr,
5482         .inode_getxattr =               selinux_inode_getxattr,
5483         .inode_listxattr =              selinux_inode_listxattr,
5484         .inode_removexattr =            selinux_inode_removexattr,
5485         .inode_getsecurity =            selinux_inode_getsecurity,
5486         .inode_setsecurity =            selinux_inode_setsecurity,
5487         .inode_listsecurity =           selinux_inode_listsecurity,
5488         .inode_getsecid =               selinux_inode_getsecid,
5489
5490         .file_permission =              selinux_file_permission,
5491         .file_alloc_security =          selinux_file_alloc_security,
5492         .file_free_security =           selinux_file_free_security,
5493         .file_ioctl =                   selinux_file_ioctl,
5494         .file_mmap =                    selinux_file_mmap,
5495         .file_mprotect =                selinux_file_mprotect,
5496         .file_lock =                    selinux_file_lock,
5497         .file_fcntl =                   selinux_file_fcntl,
5498         .file_set_fowner =              selinux_file_set_fowner,
5499         .file_send_sigiotask =          selinux_file_send_sigiotask,
5500         .file_receive =                 selinux_file_receive,
5501
5502         .dentry_open =                  selinux_dentry_open,
5503
5504         .task_create =                  selinux_task_create,
5505         .cred_alloc_blank =             selinux_cred_alloc_blank,
5506         .cred_free =                    selinux_cred_free,
5507         .cred_prepare =                 selinux_cred_prepare,
5508         .cred_transfer =                selinux_cred_transfer,
5509         .kernel_act_as =                selinux_kernel_act_as,
5510         .kernel_create_files_as =       selinux_kernel_create_files_as,
5511         .kernel_module_request =        selinux_kernel_module_request,
5512         .task_setpgid =                 selinux_task_setpgid,
5513         .task_getpgid =                 selinux_task_getpgid,
5514         .task_getsid =                  selinux_task_getsid,
5515         .task_getsecid =                selinux_task_getsecid,
5516         .task_setnice =                 selinux_task_setnice,
5517         .task_setioprio =               selinux_task_setioprio,
5518         .task_getioprio =               selinux_task_getioprio,
5519         .task_setrlimit =               selinux_task_setrlimit,
5520         .task_setscheduler =            selinux_task_setscheduler,
5521         .task_getscheduler =            selinux_task_getscheduler,
5522         .task_movememory =              selinux_task_movememory,
5523         .task_kill =                    selinux_task_kill,
5524         .task_wait =                    selinux_task_wait,
5525         .task_to_inode =                selinux_task_to_inode,
5526
5527         .ipc_permission =               selinux_ipc_permission,
5528         .ipc_getsecid =                 selinux_ipc_getsecid,
5529
5530         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5531         .msg_msg_free_security =        selinux_msg_msg_free_security,
5532
5533         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5534         .msg_queue_free_security =      selinux_msg_queue_free_security,
5535         .msg_queue_associate =          selinux_msg_queue_associate,
5536         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5537         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5538         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5539
5540         .shm_alloc_security =           selinux_shm_alloc_security,
5541         .shm_free_security =            selinux_shm_free_security,
5542         .shm_associate =                selinux_shm_associate,
5543         .shm_shmctl =                   selinux_shm_shmctl,
5544         .shm_shmat =                    selinux_shm_shmat,
5545
5546         .sem_alloc_security =           selinux_sem_alloc_security,
5547         .sem_free_security =            selinux_sem_free_security,
5548         .sem_associate =                selinux_sem_associate,
5549         .sem_semctl =                   selinux_sem_semctl,
5550         .sem_semop =                    selinux_sem_semop,
5551
5552         .d_instantiate =                selinux_d_instantiate,
5553
5554         .getprocattr =                  selinux_getprocattr,
5555         .setprocattr =                  selinux_setprocattr,
5556
5557         .secid_to_secctx =              selinux_secid_to_secctx,
5558         .secctx_to_secid =              selinux_secctx_to_secid,
5559         .release_secctx =               selinux_release_secctx,
5560         .inode_notifysecctx =           selinux_inode_notifysecctx,
5561         .inode_setsecctx =              selinux_inode_setsecctx,
5562         .inode_getsecctx =              selinux_inode_getsecctx,
5563
5564         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5565         .unix_may_send =                selinux_socket_unix_may_send,
5566
5567         .socket_create =                selinux_socket_create,
5568         .socket_post_create =           selinux_socket_post_create,
5569         .socket_bind =                  selinux_socket_bind,
5570         .socket_connect =               selinux_socket_connect,
5571         .socket_listen =                selinux_socket_listen,
5572         .socket_accept =                selinux_socket_accept,
5573         .socket_sendmsg =               selinux_socket_sendmsg,
5574         .socket_recvmsg =               selinux_socket_recvmsg,
5575         .socket_getsockname =           selinux_socket_getsockname,
5576         .socket_getpeername =           selinux_socket_getpeername,
5577         .socket_getsockopt =            selinux_socket_getsockopt,
5578         .socket_setsockopt =            selinux_socket_setsockopt,
5579         .socket_shutdown =              selinux_socket_shutdown,
5580         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5581         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5582         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5583         .sk_alloc_security =            selinux_sk_alloc_security,
5584         .sk_free_security =             selinux_sk_free_security,
5585         .sk_clone_security =            selinux_sk_clone_security,
5586         .sk_getsecid =                  selinux_sk_getsecid,
5587         .sock_graft =                   selinux_sock_graft,
5588         .inet_conn_request =            selinux_inet_conn_request,
5589         .inet_csk_clone =               selinux_inet_csk_clone,
5590         .inet_conn_established =        selinux_inet_conn_established,
5591         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5592         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5593         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5594         .req_classify_flow =            selinux_req_classify_flow,
5595         .tun_dev_create =               selinux_tun_dev_create,
5596         .tun_dev_post_create =          selinux_tun_dev_post_create,
5597         .tun_dev_attach =               selinux_tun_dev_attach,
5598
5599 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5600         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5601         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5602         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5603         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5604         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5605         .xfrm_state_free_security =     selinux_xfrm_state_free,
5606         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5607         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5608         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5609         .xfrm_decode_session =          selinux_xfrm_decode_session,
5610 #endif
5611
5612 #ifdef CONFIG_KEYS
5613         .key_alloc =                    selinux_key_alloc,
5614         .key_free =                     selinux_key_free,
5615         .key_permission =               selinux_key_permission,
5616         .key_getsecurity =              selinux_key_getsecurity,
5617 #endif
5618
5619 #ifdef CONFIG_AUDIT
5620         .audit_rule_init =              selinux_audit_rule_init,
5621         .audit_rule_known =             selinux_audit_rule_known,
5622         .audit_rule_match =             selinux_audit_rule_match,
5623         .audit_rule_free =              selinux_audit_rule_free,
5624 #endif
5625 };
5626
5627 static __init int selinux_init(void)
5628 {
5629         if (!security_module_enable(&selinux_ops)) {
5630                 selinux_enabled = 0;
5631                 return 0;
5632         }
5633
5634         if (!selinux_enabled) {
5635                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5636                 return 0;
5637         }
5638
5639         printk(KERN_INFO "SELinux:  Initializing.\n");
5640
5641         /* Set the security state for the initial task. */
5642         cred_init_security();
5643
5644         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5645
5646         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5647                                             sizeof(struct inode_security_struct),
5648                                             0, SLAB_PANIC, NULL);
5649         avc_init();
5650
5651         if (register_security(&selinux_ops))
5652                 panic("SELinux: Unable to register with kernel.\n");
5653
5654         if (selinux_enforcing)
5655                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5656         else
5657                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5658
5659         return 0;
5660 }
5661
5662 static void delayed_superblock_init(struct super_block *sb, void *unused)
5663 {
5664         superblock_doinit(sb, NULL);
5665 }
5666
5667 void selinux_complete_init(void)
5668 {
5669         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5670
5671         /* Set up any superblocks initialized prior to the policy load. */
5672         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5673         iterate_supers(delayed_superblock_init, NULL);
5674 }
5675
5676 /* SELinux requires early initialization in order to label
5677    all processes and objects when they are created. */
5678 security_initcall(selinux_init);
5679
5680 #if defined(CONFIG_NETFILTER)
5681
5682 static struct nf_hook_ops selinux_ipv4_ops[] = {
5683         {
5684                 .hook =         selinux_ipv4_postroute,
5685                 .owner =        THIS_MODULE,
5686                 .pf =           PF_INET,
5687                 .hooknum =      NF_INET_POST_ROUTING,
5688                 .priority =     NF_IP_PRI_SELINUX_LAST,
5689         },
5690         {
5691                 .hook =         selinux_ipv4_forward,
5692                 .owner =        THIS_MODULE,
5693                 .pf =           PF_INET,
5694                 .hooknum =      NF_INET_FORWARD,
5695                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5696         },
5697         {
5698                 .hook =         selinux_ipv4_output,
5699                 .owner =        THIS_MODULE,
5700                 .pf =           PF_INET,
5701                 .hooknum =      NF_INET_LOCAL_OUT,
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();
5795
5796         /* Try to destroy the avc node cache */
5797         avc_disable();
5798
5799         /* Unregister netfilter hooks. */
5800         selinux_nf_ip_exit();
5801
5802         /* Unregister selinuxfs. */
5803         exit_sel_fs();
5804
5805         return 0;
5806 }
5807 #endif