SELinux: pass last path component in may_create
[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
83 #include "avc.h"
84 #include "objsec.h"
85 #include "netif.h"
86 #include "netnode.h"
87 #include "netport.h"
88 #include "xfrm.h"
89 #include "netlabel.h"
90 #include "audit.h"
91
92 #define NUM_SEL_MNT_OPTS 5
93
94 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
95 extern struct security_operations *security_ops;
96
97 /* SECMARK reference count */
98 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
99
100 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
101 int selinux_enforcing;
102
103 static int __init enforcing_setup(char *str)
104 {
105         unsigned long enforcing;
106         if (!strict_strtoul(str, 0, &enforcing))
107                 selinux_enforcing = enforcing ? 1 : 0;
108         return 1;
109 }
110 __setup("enforcing=", enforcing_setup);
111 #endif
112
113 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
114 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
115
116 static int __init selinux_enabled_setup(char *str)
117 {
118         unsigned long enabled;
119         if (!strict_strtoul(str, 0, &enabled))
120                 selinux_enabled = enabled ? 1 : 0;
121         return 1;
122 }
123 __setup("selinux=", selinux_enabled_setup);
124 #else
125 int selinux_enabled = 1;
126 #endif
127
128 static struct kmem_cache *sel_inode_cache;
129
130 /**
131  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
132  *
133  * Description:
134  * This function checks the SECMARK reference counter to see if any SECMARK
135  * targets are currently configured, if the reference counter is greater than
136  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
137  * enabled, false (0) if SECMARK is disabled.
138  *
139  */
140 static int selinux_secmark_enabled(void)
141 {
142         return (atomic_read(&selinux_secmark_refcount) > 0);
143 }
144
145 /*
146  * initialise the security for the init task
147  */
148 static void cred_init_security(void)
149 {
150         struct cred *cred = (struct cred *) current->real_cred;
151         struct task_security_struct *tsec;
152
153         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
154         if (!tsec)
155                 panic("SELinux:  Failed to initialize initial task.\n");
156
157         tsec->osid = tsec->sid = SECINITSID_KERNEL;
158         cred->security = tsec;
159 }
160
161 /*
162  * get the security ID of a set of credentials
163  */
164 static inline u32 cred_sid(const struct cred *cred)
165 {
166         const struct task_security_struct *tsec;
167
168         tsec = cred->security;
169         return tsec->sid;
170 }
171
172 /*
173  * get the objective security ID of a task
174  */
175 static inline u32 task_sid(const struct task_struct *task)
176 {
177         u32 sid;
178
179         rcu_read_lock();
180         sid = cred_sid(__task_cred(task));
181         rcu_read_unlock();
182         return sid;
183 }
184
185 /*
186  * get the subjective security ID of the current task
187  */
188 static inline u32 current_sid(void)
189 {
190         const struct task_security_struct *tsec = current_security();
191
192         return tsec->sid;
193 }
194
195 /* Allocate and free functions for each kind of security blob. */
196
197 static int inode_alloc_security(struct inode *inode)
198 {
199         struct inode_security_struct *isec;
200         u32 sid = current_sid();
201
202         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
203         if (!isec)
204                 return -ENOMEM;
205
206         mutex_init(&isec->lock);
207         INIT_LIST_HEAD(&isec->list);
208         isec->inode = inode;
209         isec->sid = SECINITSID_UNLABELED;
210         isec->sclass = SECCLASS_FILE;
211         isec->task_sid = sid;
212         inode->i_security = isec;
213
214         return 0;
215 }
216
217 static void inode_free_security(struct inode *inode)
218 {
219         struct inode_security_struct *isec = inode->i_security;
220         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
221
222         spin_lock(&sbsec->isec_lock);
223         if (!list_empty(&isec->list))
224                 list_del_init(&isec->list);
225         spin_unlock(&sbsec->isec_lock);
226
227         inode->i_security = NULL;
228         kmem_cache_free(sel_inode_cache, isec);
229 }
230
231 static int file_alloc_security(struct file *file)
232 {
233         struct file_security_struct *fsec;
234         u32 sid = current_sid();
235
236         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
237         if (!fsec)
238                 return -ENOMEM;
239
240         fsec->sid = sid;
241         fsec->fown_sid = sid;
242         file->f_security = fsec;
243
244         return 0;
245 }
246
247 static void file_free_security(struct file *file)
248 {
249         struct file_security_struct *fsec = file->f_security;
250         file->f_security = NULL;
251         kfree(fsec);
252 }
253
254 static int superblock_alloc_security(struct super_block *sb)
255 {
256         struct superblock_security_struct *sbsec;
257
258         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
259         if (!sbsec)
260                 return -ENOMEM;
261
262         mutex_init(&sbsec->lock);
263         INIT_LIST_HEAD(&sbsec->isec_head);
264         spin_lock_init(&sbsec->isec_lock);
265         sbsec->sb = sb;
266         sbsec->sid = SECINITSID_UNLABELED;
267         sbsec->def_sid = SECINITSID_FILE;
268         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
269         sb->s_security = sbsec;
270
271         return 0;
272 }
273
274 static void superblock_free_security(struct super_block *sb)
275 {
276         struct superblock_security_struct *sbsec = sb->s_security;
277         sb->s_security = NULL;
278         kfree(sbsec);
279 }
280
281 /* The security server must be initialized before
282    any labeling or access decisions can be provided. */
283 extern int ss_initialized;
284
285 /* The file system's label must be initialized prior to use. */
286
287 static const char *labeling_behaviors[6] = {
288         "uses xattr",
289         "uses transition SIDs",
290         "uses task SIDs",
291         "uses genfs_contexts",
292         "not configured for labeling",
293         "uses mountpoint labeling",
294 };
295
296 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
297
298 static inline int inode_doinit(struct inode *inode)
299 {
300         return inode_doinit_with_dentry(inode, NULL);
301 }
302
303 enum {
304         Opt_error = -1,
305         Opt_context = 1,
306         Opt_fscontext = 2,
307         Opt_defcontext = 3,
308         Opt_rootcontext = 4,
309         Opt_labelsupport = 5,
310 };
311
312 static const match_table_t tokens = {
313         {Opt_context, CONTEXT_STR "%s"},
314         {Opt_fscontext, FSCONTEXT_STR "%s"},
315         {Opt_defcontext, DEFCONTEXT_STR "%s"},
316         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
317         {Opt_labelsupport, LABELSUPP_STR},
318         {Opt_error, NULL},
319 };
320
321 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
322
323 static int may_context_mount_sb_relabel(u32 sid,
324                         struct superblock_security_struct *sbsec,
325                         const struct cred *cred)
326 {
327         const struct task_security_struct *tsec = cred->security;
328         int rc;
329
330         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
331                           FILESYSTEM__RELABELFROM, NULL);
332         if (rc)
333                 return rc;
334
335         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
336                           FILESYSTEM__RELABELTO, NULL);
337         return rc;
338 }
339
340 static int may_context_mount_inode_relabel(u32 sid,
341                         struct superblock_security_struct *sbsec,
342                         const struct cred *cred)
343 {
344         const struct task_security_struct *tsec = cred->security;
345         int rc;
346         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
347                           FILESYSTEM__RELABELFROM, NULL);
348         if (rc)
349                 return rc;
350
351         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
352                           FILESYSTEM__ASSOCIATE, NULL);
353         return rc;
354 }
355
356 static int sb_finish_set_opts(struct super_block *sb)
357 {
358         struct superblock_security_struct *sbsec = sb->s_security;
359         struct dentry *root = sb->s_root;
360         struct inode *root_inode = root->d_inode;
361         int rc = 0;
362
363         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
364                 /* Make sure that the xattr handler exists and that no
365                    error other than -ENODATA is returned by getxattr on
366                    the root directory.  -ENODATA is ok, as this may be
367                    the first boot of the SELinux kernel before we have
368                    assigned xattr values to the filesystem. */
369                 if (!root_inode->i_op->getxattr) {
370                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
371                                "xattr support\n", sb->s_id, sb->s_type->name);
372                         rc = -EOPNOTSUPP;
373                         goto out;
374                 }
375                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
376                 if (rc < 0 && rc != -ENODATA) {
377                         if (rc == -EOPNOTSUPP)
378                                 printk(KERN_WARNING "SELinux: (dev %s, type "
379                                        "%s) has no security xattr handler\n",
380                                        sb->s_id, sb->s_type->name);
381                         else
382                                 printk(KERN_WARNING "SELinux: (dev %s, type "
383                                        "%s) getxattr errno %d\n", sb->s_id,
384                                        sb->s_type->name, -rc);
385                         goto out;
386                 }
387         }
388
389         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
390
391         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
392                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
393                        sb->s_id, sb->s_type->name);
394         else
395                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
396                        sb->s_id, sb->s_type->name,
397                        labeling_behaviors[sbsec->behavior-1]);
398
399         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
400             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
401             sbsec->behavior == SECURITY_FS_USE_NONE ||
402             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
403                 sbsec->flags &= ~SE_SBLABELSUPP;
404
405         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
406         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
407                 sbsec->flags |= SE_SBLABELSUPP;
408
409         /* Initialize the root inode. */
410         rc = inode_doinit_with_dentry(root_inode, root);
411
412         /* Initialize any other inodes associated with the superblock, e.g.
413            inodes created prior to initial policy load or inodes created
414            during get_sb by a pseudo filesystem that directly
415            populates itself. */
416         spin_lock(&sbsec->isec_lock);
417 next_inode:
418         if (!list_empty(&sbsec->isec_head)) {
419                 struct inode_security_struct *isec =
420                                 list_entry(sbsec->isec_head.next,
421                                            struct inode_security_struct, list);
422                 struct inode *inode = isec->inode;
423                 spin_unlock(&sbsec->isec_lock);
424                 inode = igrab(inode);
425                 if (inode) {
426                         if (!IS_PRIVATE(inode))
427                                 inode_doinit(inode);
428                         iput(inode);
429                 }
430                 spin_lock(&sbsec->isec_lock);
431                 list_del_init(&isec->list);
432                 goto next_inode;
433         }
434         spin_unlock(&sbsec->isec_lock);
435 out:
436         return rc;
437 }
438
439 /*
440  * This function should allow an FS to ask what it's mount security
441  * options were so it can use those later for submounts, displaying
442  * mount options, or whatever.
443  */
444 static int selinux_get_mnt_opts(const struct super_block *sb,
445                                 struct security_mnt_opts *opts)
446 {
447         int rc = 0, i;
448         struct superblock_security_struct *sbsec = sb->s_security;
449         char *context = NULL;
450         u32 len;
451         char tmp;
452
453         security_init_mnt_opts(opts);
454
455         if (!(sbsec->flags & SE_SBINITIALIZED))
456                 return -EINVAL;
457
458         if (!ss_initialized)
459                 return -EINVAL;
460
461         tmp = sbsec->flags & SE_MNTMASK;
462         /* count the number of mount options for this sb */
463         for (i = 0; i < 8; i++) {
464                 if (tmp & 0x01)
465                         opts->num_mnt_opts++;
466                 tmp >>= 1;
467         }
468         /* Check if the Label support flag is set */
469         if (sbsec->flags & SE_SBLABELSUPP)
470                 opts->num_mnt_opts++;
471
472         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
473         if (!opts->mnt_opts) {
474                 rc = -ENOMEM;
475                 goto out_free;
476         }
477
478         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
479         if (!opts->mnt_opts_flags) {
480                 rc = -ENOMEM;
481                 goto out_free;
482         }
483
484         i = 0;
485         if (sbsec->flags & FSCONTEXT_MNT) {
486                 rc = security_sid_to_context(sbsec->sid, &context, &len);
487                 if (rc)
488                         goto out_free;
489                 opts->mnt_opts[i] = context;
490                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
491         }
492         if (sbsec->flags & CONTEXT_MNT) {
493                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
494                 if (rc)
495                         goto out_free;
496                 opts->mnt_opts[i] = context;
497                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
498         }
499         if (sbsec->flags & DEFCONTEXT_MNT) {
500                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
501                 if (rc)
502                         goto out_free;
503                 opts->mnt_opts[i] = context;
504                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
505         }
506         if (sbsec->flags & ROOTCONTEXT_MNT) {
507                 struct inode *root = sbsec->sb->s_root->d_inode;
508                 struct inode_security_struct *isec = root->i_security;
509
510                 rc = security_sid_to_context(isec->sid, &context, &len);
511                 if (rc)
512                         goto out_free;
513                 opts->mnt_opts[i] = context;
514                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
515         }
516         if (sbsec->flags & SE_SBLABELSUPP) {
517                 opts->mnt_opts[i] = NULL;
518                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
519         }
520
521         BUG_ON(i != opts->num_mnt_opts);
522
523         return 0;
524
525 out_free:
526         security_free_mnt_opts(opts);
527         return rc;
528 }
529
530 static int bad_option(struct superblock_security_struct *sbsec, char flag,
531                       u32 old_sid, u32 new_sid)
532 {
533         char mnt_flags = sbsec->flags & SE_MNTMASK;
534
535         /* check if the old mount command had the same options */
536         if (sbsec->flags & SE_SBINITIALIZED)
537                 if (!(sbsec->flags & flag) ||
538                     (old_sid != new_sid))
539                         return 1;
540
541         /* check if we were passed the same options twice,
542          * aka someone passed context=a,context=b
543          */
544         if (!(sbsec->flags & SE_SBINITIALIZED))
545                 if (mnt_flags & flag)
546                         return 1;
547         return 0;
548 }
549
550 /*
551  * Allow filesystems with binary mount data to explicitly set mount point
552  * labeling information.
553  */
554 static int selinux_set_mnt_opts(struct super_block *sb,
555                                 struct security_mnt_opts *opts)
556 {
557         const struct cred *cred = current_cred();
558         int rc = 0, i;
559         struct superblock_security_struct *sbsec = sb->s_security;
560         const char *name = sb->s_type->name;
561         struct inode *inode = sbsec->sb->s_root->d_inode;
562         struct inode_security_struct *root_isec = inode->i_security;
563         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
564         u32 defcontext_sid = 0;
565         char **mount_options = opts->mnt_opts;
566         int *flags = opts->mnt_opts_flags;
567         int num_opts = opts->num_mnt_opts;
568
569         mutex_lock(&sbsec->lock);
570
571         if (!ss_initialized) {
572                 if (!num_opts) {
573                         /* Defer initialization until selinux_complete_init,
574                            after the initial policy is loaded and the security
575                            server is ready to handle calls. */
576                         goto out;
577                 }
578                 rc = -EINVAL;
579                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
580                         "before the security server is initialized\n");
581                 goto out;
582         }
583
584         /*
585          * Binary mount data FS will come through this function twice.  Once
586          * from an explicit call and once from the generic calls from the vfs.
587          * Since the generic VFS calls will not contain any security mount data
588          * we need to skip the double mount verification.
589          *
590          * This does open a hole in which we will not notice if the first
591          * mount using this sb set explict options and a second mount using
592          * this sb does not set any security options.  (The first options
593          * will be used for both mounts)
594          */
595         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
596             && (num_opts == 0))
597                 goto out;
598
599         /*
600          * parse the mount options, check if they are valid sids.
601          * also check if someone is trying to mount the same sb more
602          * than once with different security options.
603          */
604         for (i = 0; i < num_opts; i++) {
605                 u32 sid;
606
607                 if (flags[i] == SE_SBLABELSUPP)
608                         continue;
609                 rc = security_context_to_sid(mount_options[i],
610                                              strlen(mount_options[i]), &sid);
611                 if (rc) {
612                         printk(KERN_WARNING "SELinux: security_context_to_sid"
613                                "(%s) failed for (dev %s, type %s) errno=%d\n",
614                                mount_options[i], sb->s_id, name, rc);
615                         goto out;
616                 }
617                 switch (flags[i]) {
618                 case FSCONTEXT_MNT:
619                         fscontext_sid = sid;
620
621                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
622                                         fscontext_sid))
623                                 goto out_double_mount;
624
625                         sbsec->flags |= FSCONTEXT_MNT;
626                         break;
627                 case CONTEXT_MNT:
628                         context_sid = sid;
629
630                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
631                                         context_sid))
632                                 goto out_double_mount;
633
634                         sbsec->flags |= CONTEXT_MNT;
635                         break;
636                 case ROOTCONTEXT_MNT:
637                         rootcontext_sid = sid;
638
639                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
640                                         rootcontext_sid))
641                                 goto out_double_mount;
642
643                         sbsec->flags |= ROOTCONTEXT_MNT;
644
645                         break;
646                 case DEFCONTEXT_MNT:
647                         defcontext_sid = sid;
648
649                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
650                                         defcontext_sid))
651                                 goto out_double_mount;
652
653                         sbsec->flags |= DEFCONTEXT_MNT;
654
655                         break;
656                 default:
657                         rc = -EINVAL;
658                         goto out;
659                 }
660         }
661
662         if (sbsec->flags & SE_SBINITIALIZED) {
663                 /* previously mounted with options, but not on this attempt? */
664                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
665                         goto out_double_mount;
666                 rc = 0;
667                 goto out;
668         }
669
670         if (strcmp(sb->s_type->name, "proc") == 0)
671                 sbsec->flags |= SE_SBPROC;
672
673         /* Determine the labeling behavior to use for this filesystem type. */
674         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
675         if (rc) {
676                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
677                        __func__, sb->s_type->name, rc);
678                 goto out;
679         }
680
681         /* sets the context of the superblock for the fs being mounted. */
682         if (fscontext_sid) {
683                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
684                 if (rc)
685                         goto out;
686
687                 sbsec->sid = fscontext_sid;
688         }
689
690         /*
691          * Switch to using mount point labeling behavior.
692          * sets the label used on all file below the mountpoint, and will set
693          * the superblock context if not already set.
694          */
695         if (context_sid) {
696                 if (!fscontext_sid) {
697                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
698                                                           cred);
699                         if (rc)
700                                 goto out;
701                         sbsec->sid = context_sid;
702                 } else {
703                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
704                                                              cred);
705                         if (rc)
706                                 goto out;
707                 }
708                 if (!rootcontext_sid)
709                         rootcontext_sid = context_sid;
710
711                 sbsec->mntpoint_sid = context_sid;
712                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
713         }
714
715         if (rootcontext_sid) {
716                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
717                                                      cred);
718                 if (rc)
719                         goto out;
720
721                 root_isec->sid = rootcontext_sid;
722                 root_isec->initialized = 1;
723         }
724
725         if (defcontext_sid) {
726                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
727                         rc = -EINVAL;
728                         printk(KERN_WARNING "SELinux: defcontext option is "
729                                "invalid for this filesystem type\n");
730                         goto out;
731                 }
732
733                 if (defcontext_sid != sbsec->def_sid) {
734                         rc = may_context_mount_inode_relabel(defcontext_sid,
735                                                              sbsec, cred);
736                         if (rc)
737                                 goto out;
738                 }
739
740                 sbsec->def_sid = defcontext_sid;
741         }
742
743         rc = sb_finish_set_opts(sb);
744 out:
745         mutex_unlock(&sbsec->lock);
746         return rc;
747 out_double_mount:
748         rc = -EINVAL;
749         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
750                "security settings for (dev %s, type %s)\n", sb->s_id, name);
751         goto out;
752 }
753
754 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
755                                         struct super_block *newsb)
756 {
757         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
758         struct superblock_security_struct *newsbsec = newsb->s_security;
759
760         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
761         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
762         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
763
764         /*
765          * if the parent was able to be mounted it clearly had no special lsm
766          * mount options.  thus we can safely deal with this superblock later
767          */
768         if (!ss_initialized)
769                 return;
770
771         /* how can we clone if the old one wasn't set up?? */
772         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
773
774         /* if fs is reusing a sb, just let its options stand... */
775         if (newsbsec->flags & SE_SBINITIALIZED)
776                 return;
777
778         mutex_lock(&newsbsec->lock);
779
780         newsbsec->flags = oldsbsec->flags;
781
782         newsbsec->sid = oldsbsec->sid;
783         newsbsec->def_sid = oldsbsec->def_sid;
784         newsbsec->behavior = oldsbsec->behavior;
785
786         if (set_context) {
787                 u32 sid = oldsbsec->mntpoint_sid;
788
789                 if (!set_fscontext)
790                         newsbsec->sid = sid;
791                 if (!set_rootcontext) {
792                         struct inode *newinode = newsb->s_root->d_inode;
793                         struct inode_security_struct *newisec = newinode->i_security;
794                         newisec->sid = sid;
795                 }
796                 newsbsec->mntpoint_sid = sid;
797         }
798         if (set_rootcontext) {
799                 const struct inode *oldinode = oldsb->s_root->d_inode;
800                 const struct inode_security_struct *oldisec = oldinode->i_security;
801                 struct inode *newinode = newsb->s_root->d_inode;
802                 struct inode_security_struct *newisec = newinode->i_security;
803
804                 newisec->sid = oldisec->sid;
805         }
806
807         sb_finish_set_opts(newsb);
808         mutex_unlock(&newsbsec->lock);
809 }
810
811 static int selinux_parse_opts_str(char *options,
812                                   struct security_mnt_opts *opts)
813 {
814         char *p;
815         char *context = NULL, *defcontext = NULL;
816         char *fscontext = NULL, *rootcontext = NULL;
817         int rc, num_mnt_opts = 0;
818
819         opts->num_mnt_opts = 0;
820
821         /* Standard string-based options. */
822         while ((p = strsep(&options, "|")) != NULL) {
823                 int token;
824                 substring_t args[MAX_OPT_ARGS];
825
826                 if (!*p)
827                         continue;
828
829                 token = match_token(p, tokens, args);
830
831                 switch (token) {
832                 case Opt_context:
833                         if (context || defcontext) {
834                                 rc = -EINVAL;
835                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
836                                 goto out_err;
837                         }
838                         context = match_strdup(&args[0]);
839                         if (!context) {
840                                 rc = -ENOMEM;
841                                 goto out_err;
842                         }
843                         break;
844
845                 case Opt_fscontext:
846                         if (fscontext) {
847                                 rc = -EINVAL;
848                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
849                                 goto out_err;
850                         }
851                         fscontext = match_strdup(&args[0]);
852                         if (!fscontext) {
853                                 rc = -ENOMEM;
854                                 goto out_err;
855                         }
856                         break;
857
858                 case Opt_rootcontext:
859                         if (rootcontext) {
860                                 rc = -EINVAL;
861                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
862                                 goto out_err;
863                         }
864                         rootcontext = match_strdup(&args[0]);
865                         if (!rootcontext) {
866                                 rc = -ENOMEM;
867                                 goto out_err;
868                         }
869                         break;
870
871                 case Opt_defcontext:
872                         if (context || defcontext) {
873                                 rc = -EINVAL;
874                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
875                                 goto out_err;
876                         }
877                         defcontext = match_strdup(&args[0]);
878                         if (!defcontext) {
879                                 rc = -ENOMEM;
880                                 goto out_err;
881                         }
882                         break;
883                 case Opt_labelsupport:
884                         break;
885                 default:
886                         rc = -EINVAL;
887                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
888                         goto out_err;
889
890                 }
891         }
892
893         rc = -ENOMEM;
894         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
895         if (!opts->mnt_opts)
896                 goto out_err;
897
898         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
899         if (!opts->mnt_opts_flags) {
900                 kfree(opts->mnt_opts);
901                 goto out_err;
902         }
903
904         if (fscontext) {
905                 opts->mnt_opts[num_mnt_opts] = fscontext;
906                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
907         }
908         if (context) {
909                 opts->mnt_opts[num_mnt_opts] = context;
910                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
911         }
912         if (rootcontext) {
913                 opts->mnt_opts[num_mnt_opts] = rootcontext;
914                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
915         }
916         if (defcontext) {
917                 opts->mnt_opts[num_mnt_opts] = defcontext;
918                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
919         }
920
921         opts->num_mnt_opts = num_mnt_opts;
922         return 0;
923
924 out_err:
925         kfree(context);
926         kfree(defcontext);
927         kfree(fscontext);
928         kfree(rootcontext);
929         return rc;
930 }
931 /*
932  * string mount options parsing and call set the sbsec
933  */
934 static int superblock_doinit(struct super_block *sb, void *data)
935 {
936         int rc = 0;
937         char *options = data;
938         struct security_mnt_opts opts;
939
940         security_init_mnt_opts(&opts);
941
942         if (!data)
943                 goto out;
944
945         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
946
947         rc = selinux_parse_opts_str(options, &opts);
948         if (rc)
949                 goto out_err;
950
951 out:
952         rc = selinux_set_mnt_opts(sb, &opts);
953
954 out_err:
955         security_free_mnt_opts(&opts);
956         return rc;
957 }
958
959 static void selinux_write_opts(struct seq_file *m,
960                                struct security_mnt_opts *opts)
961 {
962         int i;
963         char *prefix;
964
965         for (i = 0; i < opts->num_mnt_opts; i++) {
966                 char *has_comma;
967
968                 if (opts->mnt_opts[i])
969                         has_comma = strchr(opts->mnt_opts[i], ',');
970                 else
971                         has_comma = NULL;
972
973                 switch (opts->mnt_opts_flags[i]) {
974                 case CONTEXT_MNT:
975                         prefix = CONTEXT_STR;
976                         break;
977                 case FSCONTEXT_MNT:
978                         prefix = FSCONTEXT_STR;
979                         break;
980                 case ROOTCONTEXT_MNT:
981                         prefix = ROOTCONTEXT_STR;
982                         break;
983                 case DEFCONTEXT_MNT:
984                         prefix = DEFCONTEXT_STR;
985                         break;
986                 case SE_SBLABELSUPP:
987                         seq_putc(m, ',');
988                         seq_puts(m, LABELSUPP_STR);
989                         continue;
990                 default:
991                         BUG();
992                         return;
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                 return -EINVAL;
1447         }
1448
1449         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1450         if (audit == SECURITY_CAP_AUDIT) {
1451                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1452                 if (rc2)
1453                         return rc2;
1454         }
1455         return rc;
1456 }
1457
1458 /* Check whether a task is allowed to use a system operation. */
1459 static int task_has_system(struct task_struct *tsk,
1460                            u32 perms)
1461 {
1462         u32 sid = task_sid(tsk);
1463
1464         return avc_has_perm(sid, SECINITSID_KERNEL,
1465                             SECCLASS_SYSTEM, perms, NULL);
1466 }
1467
1468 /* Check whether a task has a particular permission to an inode.
1469    The 'adp' parameter is optional and allows other audit
1470    data to be passed (e.g. the dentry). */
1471 static int inode_has_perm(const struct cred *cred,
1472                           struct inode *inode,
1473                           u32 perms,
1474                           struct common_audit_data *adp,
1475                           unsigned flags)
1476 {
1477         struct inode_security_struct *isec;
1478         struct common_audit_data ad;
1479         u32 sid;
1480
1481         validate_creds(cred);
1482
1483         if (unlikely(IS_PRIVATE(inode)))
1484                 return 0;
1485
1486         sid = cred_sid(cred);
1487         isec = inode->i_security;
1488
1489         if (!adp) {
1490                 adp = &ad;
1491                 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1492                 ad.u.inode = inode;
1493         }
1494
1495         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1496 }
1497
1498 /* Same as inode_has_perm, but pass explicit audit data containing
1499    the dentry to help the auditing code to more easily generate the
1500    pathname if needed. */
1501 static inline int dentry_has_perm(const struct cred *cred,
1502                                   struct vfsmount *mnt,
1503                                   struct dentry *dentry,
1504                                   u32 av)
1505 {
1506         struct inode *inode = dentry->d_inode;
1507         struct common_audit_data ad;
1508
1509         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1510         ad.u.path.mnt = mnt;
1511         ad.u.path.dentry = dentry;
1512         return inode_has_perm(cred, inode, av, &ad, 0);
1513 }
1514
1515 /* Check whether a task can use an open file descriptor to
1516    access an inode in a given way.  Check access to the
1517    descriptor itself, and then use dentry_has_perm to
1518    check a particular permission to the file.
1519    Access to the descriptor is implicitly granted if it
1520    has the same SID as the process.  If av is zero, then
1521    access to the file is not checked, e.g. for cases
1522    where only the descriptor is affected like seek. */
1523 static int file_has_perm(const struct cred *cred,
1524                          struct file *file,
1525                          u32 av)
1526 {
1527         struct file_security_struct *fsec = file->f_security;
1528         struct inode *inode = file->f_path.dentry->d_inode;
1529         struct common_audit_data ad;
1530         u32 sid = cred_sid(cred);
1531         int rc;
1532
1533         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1534         ad.u.path = file->f_path;
1535
1536         if (sid != fsec->sid) {
1537                 rc = avc_has_perm(sid, fsec->sid,
1538                                   SECCLASS_FD,
1539                                   FD__USE,
1540                                   &ad);
1541                 if (rc)
1542                         goto out;
1543         }
1544
1545         /* av is zero if only checking access to the descriptor. */
1546         rc = 0;
1547         if (av)
1548                 rc = inode_has_perm(cred, inode, av, &ad, 0);
1549
1550 out:
1551         return rc;
1552 }
1553
1554 /* Check whether a task can create a file. */
1555 static int may_create(struct inode *dir,
1556                       struct dentry *dentry,
1557                       u16 tclass)
1558 {
1559         const struct task_security_struct *tsec = current_security();
1560         struct inode_security_struct *dsec;
1561         struct superblock_security_struct *sbsec;
1562         u32 sid, newsid;
1563         struct common_audit_data ad;
1564         int rc;
1565
1566         dsec = dir->i_security;
1567         sbsec = dir->i_sb->s_security;
1568
1569         sid = tsec->sid;
1570         newsid = tsec->create_sid;
1571
1572         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1573         ad.u.dentry = dentry;
1574
1575         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1576                           DIR__ADD_NAME | DIR__SEARCH,
1577                           &ad);
1578         if (rc)
1579                 return rc;
1580
1581         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1582                 rc = security_transition_sid(sid, dsec->sid, tclass,
1583                                              &dentry->d_name, &newsid);
1584                 if (rc)
1585                         return rc;
1586         }
1587
1588         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1589         if (rc)
1590                 return rc;
1591
1592         return avc_has_perm(newsid, sbsec->sid,
1593                             SECCLASS_FILESYSTEM,
1594                             FILESYSTEM__ASSOCIATE, &ad);
1595 }
1596
1597 /* Check whether a task can create a key. */
1598 static int may_create_key(u32 ksid,
1599                           struct task_struct *ctx)
1600 {
1601         u32 sid = task_sid(ctx);
1602
1603         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1604 }
1605
1606 #define MAY_LINK        0
1607 #define MAY_UNLINK      1
1608 #define MAY_RMDIR       2
1609
1610 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1611 static int may_link(struct inode *dir,
1612                     struct dentry *dentry,
1613                     int kind)
1614
1615 {
1616         struct inode_security_struct *dsec, *isec;
1617         struct common_audit_data ad;
1618         u32 sid = current_sid();
1619         u32 av;
1620         int rc;
1621
1622         dsec = dir->i_security;
1623         isec = dentry->d_inode->i_security;
1624
1625         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1626         ad.u.dentry = dentry;
1627
1628         av = DIR__SEARCH;
1629         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1630         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1631         if (rc)
1632                 return rc;
1633
1634         switch (kind) {
1635         case MAY_LINK:
1636                 av = FILE__LINK;
1637                 break;
1638         case MAY_UNLINK:
1639                 av = FILE__UNLINK;
1640                 break;
1641         case MAY_RMDIR:
1642                 av = DIR__RMDIR;
1643                 break;
1644         default:
1645                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1646                         __func__, kind);
1647                 return 0;
1648         }
1649
1650         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1651         return rc;
1652 }
1653
1654 static inline int may_rename(struct inode *old_dir,
1655                              struct dentry *old_dentry,
1656                              struct inode *new_dir,
1657                              struct dentry *new_dentry)
1658 {
1659         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1660         struct common_audit_data ad;
1661         u32 sid = current_sid();
1662         u32 av;
1663         int old_is_dir, new_is_dir;
1664         int rc;
1665
1666         old_dsec = old_dir->i_security;
1667         old_isec = old_dentry->d_inode->i_security;
1668         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1669         new_dsec = new_dir->i_security;
1670
1671         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1672
1673         ad.u.dentry = old_dentry;
1674         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1675                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1676         if (rc)
1677                 return rc;
1678         rc = avc_has_perm(sid, old_isec->sid,
1679                           old_isec->sclass, FILE__RENAME, &ad);
1680         if (rc)
1681                 return rc;
1682         if (old_is_dir && new_dir != old_dir) {
1683                 rc = avc_has_perm(sid, old_isec->sid,
1684                                   old_isec->sclass, DIR__REPARENT, &ad);
1685                 if (rc)
1686                         return rc;
1687         }
1688
1689         ad.u.dentry = new_dentry;
1690         av = DIR__ADD_NAME | DIR__SEARCH;
1691         if (new_dentry->d_inode)
1692                 av |= DIR__REMOVE_NAME;
1693         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1694         if (rc)
1695                 return rc;
1696         if (new_dentry->d_inode) {
1697                 new_isec = new_dentry->d_inode->i_security;
1698                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1699                 rc = avc_has_perm(sid, new_isec->sid,
1700                                   new_isec->sclass,
1701                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1702                 if (rc)
1703                         return rc;
1704         }
1705
1706         return 0;
1707 }
1708
1709 /* Check whether a task can perform a filesystem operation. */
1710 static int superblock_has_perm(const struct cred *cred,
1711                                struct super_block *sb,
1712                                u32 perms,
1713                                struct common_audit_data *ad)
1714 {
1715         struct superblock_security_struct *sbsec;
1716         u32 sid = cred_sid(cred);
1717
1718         sbsec = sb->s_security;
1719         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1720 }
1721
1722 /* Convert a Linux mode and permission mask to an access vector. */
1723 static inline u32 file_mask_to_av(int mode, int mask)
1724 {
1725         u32 av = 0;
1726
1727         if ((mode & S_IFMT) != S_IFDIR) {
1728                 if (mask & MAY_EXEC)
1729                         av |= FILE__EXECUTE;
1730                 if (mask & MAY_READ)
1731                         av |= FILE__READ;
1732
1733                 if (mask & MAY_APPEND)
1734                         av |= FILE__APPEND;
1735                 else if (mask & MAY_WRITE)
1736                         av |= FILE__WRITE;
1737
1738         } else {
1739                 if (mask & MAY_EXEC)
1740                         av |= DIR__SEARCH;
1741                 if (mask & MAY_WRITE)
1742                         av |= DIR__WRITE;
1743                 if (mask & MAY_READ)
1744                         av |= DIR__READ;
1745         }
1746
1747         return av;
1748 }
1749
1750 /* Convert a Linux file to an access vector. */
1751 static inline u32 file_to_av(struct file *file)
1752 {
1753         u32 av = 0;
1754
1755         if (file->f_mode & FMODE_READ)
1756                 av |= FILE__READ;
1757         if (file->f_mode & FMODE_WRITE) {
1758                 if (file->f_flags & O_APPEND)
1759                         av |= FILE__APPEND;
1760                 else
1761                         av |= FILE__WRITE;
1762         }
1763         if (!av) {
1764                 /*
1765                  * Special file opened with flags 3 for ioctl-only use.
1766                  */
1767                 av = FILE__IOCTL;
1768         }
1769
1770         return av;
1771 }
1772
1773 /*
1774  * Convert a file to an access vector and include the correct open
1775  * open permission.
1776  */
1777 static inline u32 open_file_to_av(struct file *file)
1778 {
1779         u32 av = file_to_av(file);
1780
1781         if (selinux_policycap_openperm)
1782                 av |= FILE__OPEN;
1783
1784         return av;
1785 }
1786
1787 /* Hook functions begin here. */
1788
1789 static int selinux_ptrace_access_check(struct task_struct *child,
1790                                      unsigned int mode)
1791 {
1792         int rc;
1793
1794         rc = cap_ptrace_access_check(child, mode);
1795         if (rc)
1796                 return rc;
1797
1798         if (mode == PTRACE_MODE_READ) {
1799                 u32 sid = current_sid();
1800                 u32 csid = task_sid(child);
1801                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1802         }
1803
1804         return current_has_perm(child, PROCESS__PTRACE);
1805 }
1806
1807 static int selinux_ptrace_traceme(struct task_struct *parent)
1808 {
1809         int rc;
1810
1811         rc = cap_ptrace_traceme(parent);
1812         if (rc)
1813                 return rc;
1814
1815         return task_has_perm(parent, current, PROCESS__PTRACE);
1816 }
1817
1818 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1819                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1820 {
1821         int error;
1822
1823         error = current_has_perm(target, PROCESS__GETCAP);
1824         if (error)
1825                 return error;
1826
1827         return cap_capget(target, effective, inheritable, permitted);
1828 }
1829
1830 static int selinux_capset(struct cred *new, const struct cred *old,
1831                           const kernel_cap_t *effective,
1832                           const kernel_cap_t *inheritable,
1833                           const kernel_cap_t *permitted)
1834 {
1835         int error;
1836
1837         error = cap_capset(new, old,
1838                                       effective, inheritable, permitted);
1839         if (error)
1840                 return error;
1841
1842         return cred_has_perm(old, new, PROCESS__SETCAP);
1843 }
1844
1845 /*
1846  * (This comment used to live with the selinux_task_setuid hook,
1847  * which was removed).
1848  *
1849  * Since setuid only affects the current process, and since the SELinux
1850  * controls are not based on the Linux identity attributes, SELinux does not
1851  * need to control this operation.  However, SELinux does control the use of
1852  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1853  */
1854
1855 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1856                            int cap, int audit)
1857 {
1858         int rc;
1859
1860         rc = cap_capable(tsk, cred, cap, audit);
1861         if (rc)
1862                 return rc;
1863
1864         return task_has_capability(tsk, cred, cap, audit);
1865 }
1866
1867 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1868 {
1869         const struct cred *cred = current_cred();
1870         int rc = 0;
1871
1872         if (!sb)
1873                 return 0;
1874
1875         switch (cmds) {
1876         case Q_SYNC:
1877         case Q_QUOTAON:
1878         case Q_QUOTAOFF:
1879         case Q_SETINFO:
1880         case Q_SETQUOTA:
1881                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1882                 break;
1883         case Q_GETFMT:
1884         case Q_GETINFO:
1885         case Q_GETQUOTA:
1886                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1887                 break;
1888         default:
1889                 rc = 0;  /* let the kernel handle invalid cmds */
1890                 break;
1891         }
1892         return rc;
1893 }
1894
1895 static int selinux_quota_on(struct dentry *dentry)
1896 {
1897         const struct cred *cred = current_cred();
1898
1899         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1900 }
1901
1902 static int selinux_syslog(int type)
1903 {
1904         int rc;
1905
1906         switch (type) {
1907         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1908         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1909                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1910                 break;
1911         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1912         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1913         /* Set level of messages printed to console */
1914         case SYSLOG_ACTION_CONSOLE_LEVEL:
1915                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1916                 break;
1917         case SYSLOG_ACTION_CLOSE:       /* Close log */
1918         case SYSLOG_ACTION_OPEN:        /* Open log */
1919         case SYSLOG_ACTION_READ:        /* Read from log */
1920         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1921         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1922         default:
1923                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1924                 break;
1925         }
1926         return rc;
1927 }
1928
1929 /*
1930  * Check that a process has enough memory to allocate a new virtual
1931  * mapping. 0 means there is enough memory for the allocation to
1932  * succeed and -ENOMEM implies there is not.
1933  *
1934  * Do not audit the selinux permission check, as this is applied to all
1935  * processes that allocate mappings.
1936  */
1937 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1938 {
1939         int rc, cap_sys_admin = 0;
1940
1941         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
1942                              SECURITY_CAP_NOAUDIT);
1943         if (rc == 0)
1944                 cap_sys_admin = 1;
1945
1946         return __vm_enough_memory(mm, pages, cap_sys_admin);
1947 }
1948
1949 /* binprm security operations */
1950
1951 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1952 {
1953         const struct task_security_struct *old_tsec;
1954         struct task_security_struct *new_tsec;
1955         struct inode_security_struct *isec;
1956         struct common_audit_data ad;
1957         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1958         int rc;
1959
1960         rc = cap_bprm_set_creds(bprm);
1961         if (rc)
1962                 return rc;
1963
1964         /* SELinux context only depends on initial program or script and not
1965          * the script interpreter */
1966         if (bprm->cred_prepared)
1967                 return 0;
1968
1969         old_tsec = current_security();
1970         new_tsec = bprm->cred->security;
1971         isec = inode->i_security;
1972
1973         /* Default to the current task SID. */
1974         new_tsec->sid = old_tsec->sid;
1975         new_tsec->osid = old_tsec->sid;
1976
1977         /* Reset fs, key, and sock SIDs on execve. */
1978         new_tsec->create_sid = 0;
1979         new_tsec->keycreate_sid = 0;
1980         new_tsec->sockcreate_sid = 0;
1981
1982         if (old_tsec->exec_sid) {
1983                 new_tsec->sid = old_tsec->exec_sid;
1984                 /* Reset exec SID on execve. */
1985                 new_tsec->exec_sid = 0;
1986         } else {
1987                 /* Check for a default transition on this program. */
1988                 rc = security_transition_sid(old_tsec->sid, isec->sid,
1989                                              SECCLASS_PROCESS, NULL,
1990                                              &new_tsec->sid);
1991                 if (rc)
1992                         return rc;
1993         }
1994
1995         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1996         ad.u.path = bprm->file->f_path;
1997
1998         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
1999                 new_tsec->sid = old_tsec->sid;
2000
2001         if (new_tsec->sid == old_tsec->sid) {
2002                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2003                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2004                 if (rc)
2005                         return rc;
2006         } else {
2007                 /* Check permissions for the transition. */
2008                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2009                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2010                 if (rc)
2011                         return rc;
2012
2013                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2014                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2015                 if (rc)
2016                         return rc;
2017
2018                 /* Check for shared state */
2019                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2020                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2021                                           SECCLASS_PROCESS, PROCESS__SHARE,
2022                                           NULL);
2023                         if (rc)
2024                                 return -EPERM;
2025                 }
2026
2027                 /* Make sure that anyone attempting to ptrace over a task that
2028                  * changes its SID has the appropriate permit */
2029                 if (bprm->unsafe &
2030                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2031                         struct task_struct *tracer;
2032                         struct task_security_struct *sec;
2033                         u32 ptsid = 0;
2034
2035                         rcu_read_lock();
2036                         tracer = tracehook_tracer_task(current);
2037                         if (likely(tracer != NULL)) {
2038                                 sec = __task_cred(tracer)->security;
2039                                 ptsid = sec->sid;
2040                         }
2041                         rcu_read_unlock();
2042
2043                         if (ptsid != 0) {
2044                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2045                                                   SECCLASS_PROCESS,
2046                                                   PROCESS__PTRACE, NULL);
2047                                 if (rc)
2048                                         return -EPERM;
2049                         }
2050                 }
2051
2052                 /* Clear any possibly unsafe personality bits on exec: */
2053                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2054         }
2055
2056         return 0;
2057 }
2058
2059 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2060 {
2061         const struct task_security_struct *tsec = current_security();
2062         u32 sid, osid;
2063         int atsecure = 0;
2064
2065         sid = tsec->sid;
2066         osid = tsec->osid;
2067
2068         if (osid != sid) {
2069                 /* Enable secure mode for SIDs transitions unless
2070                    the noatsecure permission is granted between
2071                    the two SIDs, i.e. ahp returns 0. */
2072                 atsecure = avc_has_perm(osid, sid,
2073                                         SECCLASS_PROCESS,
2074                                         PROCESS__NOATSECURE, NULL);
2075         }
2076
2077         return (atsecure || cap_bprm_secureexec(bprm));
2078 }
2079
2080 extern struct vfsmount *selinuxfs_mount;
2081 extern struct dentry *selinux_null;
2082
2083 /* Derived from fs/exec.c:flush_old_files. */
2084 static inline void flush_unauthorized_files(const struct cred *cred,
2085                                             struct files_struct *files)
2086 {
2087         struct common_audit_data ad;
2088         struct file *file, *devnull = NULL;
2089         struct tty_struct *tty;
2090         struct fdtable *fdt;
2091         long j = -1;
2092         int drop_tty = 0;
2093
2094         tty = get_current_tty();
2095         if (tty) {
2096                 spin_lock(&tty_files_lock);
2097                 if (!list_empty(&tty->tty_files)) {
2098                         struct tty_file_private *file_priv;
2099                         struct inode *inode;
2100
2101                         /* Revalidate access to controlling tty.
2102                            Use inode_has_perm on the tty inode directly rather
2103                            than using file_has_perm, as this particular open
2104                            file may belong to another process and we are only
2105                            interested in the inode-based check here. */
2106                         file_priv = list_first_entry(&tty->tty_files,
2107                                                 struct tty_file_private, list);
2108                         file = file_priv->file;
2109                         inode = file->f_path.dentry->d_inode;
2110                         if (inode_has_perm(cred, inode,
2111                                            FILE__READ | FILE__WRITE, NULL, 0)) {
2112                                 drop_tty = 1;
2113                         }
2114                 }
2115                 spin_unlock(&tty_files_lock);
2116                 tty_kref_put(tty);
2117         }
2118         /* Reset controlling tty. */
2119         if (drop_tty)
2120                 no_tty();
2121
2122         /* Revalidate access to inherited open files. */
2123
2124         COMMON_AUDIT_DATA_INIT(&ad, INODE);
2125
2126         spin_lock(&files->file_lock);
2127         for (;;) {
2128                 unsigned long set, i;
2129                 int fd;
2130
2131                 j++;
2132                 i = j * __NFDBITS;
2133                 fdt = files_fdtable(files);
2134                 if (i >= fdt->max_fds)
2135                         break;
2136                 set = fdt->open_fds->fds_bits[j];
2137                 if (!set)
2138                         continue;
2139                 spin_unlock(&files->file_lock);
2140                 for ( ; set ; i++, set >>= 1) {
2141                         if (set & 1) {
2142                                 file = fget(i);
2143                                 if (!file)
2144                                         continue;
2145                                 if (file_has_perm(cred,
2146                                                   file,
2147                                                   file_to_av(file))) {
2148                                         sys_close(i);
2149                                         fd = get_unused_fd();
2150                                         if (fd != i) {
2151                                                 if (fd >= 0)
2152                                                         put_unused_fd(fd);
2153                                                 fput(file);
2154                                                 continue;
2155                                         }
2156                                         if (devnull) {
2157                                                 get_file(devnull);
2158                                         } else {
2159                                                 devnull = dentry_open(
2160                                                         dget(selinux_null),
2161                                                         mntget(selinuxfs_mount),
2162                                                         O_RDWR, cred);
2163                                                 if (IS_ERR(devnull)) {
2164                                                         devnull = NULL;
2165                                                         put_unused_fd(fd);
2166                                                         fput(file);
2167                                                         continue;
2168                                                 }
2169                                         }
2170                                         fd_install(fd, devnull);
2171                                 }
2172                                 fput(file);
2173                         }
2174                 }
2175                 spin_lock(&files->file_lock);
2176
2177         }
2178         spin_unlock(&files->file_lock);
2179 }
2180
2181 /*
2182  * Prepare a process for imminent new credential changes due to exec
2183  */
2184 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2185 {
2186         struct task_security_struct *new_tsec;
2187         struct rlimit *rlim, *initrlim;
2188         int rc, i;
2189
2190         new_tsec = bprm->cred->security;
2191         if (new_tsec->sid == new_tsec->osid)
2192                 return;
2193
2194         /* Close files for which the new task SID is not authorized. */
2195         flush_unauthorized_files(bprm->cred, current->files);
2196
2197         /* Always clear parent death signal on SID transitions. */
2198         current->pdeath_signal = 0;
2199
2200         /* Check whether the new SID can inherit resource limits from the old
2201          * SID.  If not, reset all soft limits to the lower of the current
2202          * task's hard limit and the init task's soft limit.
2203          *
2204          * Note that the setting of hard limits (even to lower them) can be
2205          * controlled by the setrlimit check.  The inclusion of the init task's
2206          * soft limit into the computation is to avoid resetting soft limits
2207          * higher than the default soft limit for cases where the default is
2208          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2209          */
2210         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2211                           PROCESS__RLIMITINH, NULL);
2212         if (rc) {
2213                 /* protect against do_prlimit() */
2214                 task_lock(current);
2215                 for (i = 0; i < RLIM_NLIMITS; i++) {
2216                         rlim = current->signal->rlim + i;
2217                         initrlim = init_task.signal->rlim + i;
2218                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2219                 }
2220                 task_unlock(current);
2221                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2222         }
2223 }
2224
2225 /*
2226  * Clean up the process immediately after the installation of new credentials
2227  * due to exec
2228  */
2229 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2230 {
2231         const struct task_security_struct *tsec = current_security();
2232         struct itimerval itimer;
2233         u32 osid, sid;
2234         int rc, i;
2235
2236         osid = tsec->osid;
2237         sid = tsec->sid;
2238
2239         if (sid == osid)
2240                 return;
2241
2242         /* Check whether the new SID can inherit signal state from the old SID.
2243          * If not, clear itimers to avoid subsequent signal generation and
2244          * flush and unblock signals.
2245          *
2246          * This must occur _after_ the task SID has been updated so that any
2247          * kill done after the flush will be checked against the new SID.
2248          */
2249         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2250         if (rc) {
2251                 memset(&itimer, 0, sizeof itimer);
2252                 for (i = 0; i < 3; i++)
2253                         do_setitimer(i, &itimer, NULL);
2254                 spin_lock_irq(&current->sighand->siglock);
2255                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2256                         __flush_signals(current);
2257                         flush_signal_handlers(current, 1);
2258                         sigemptyset(&current->blocked);
2259                 }
2260                 spin_unlock_irq(&current->sighand->siglock);
2261         }
2262
2263         /* Wake up the parent if it is waiting so that it can recheck
2264          * wait permission to the new task SID. */
2265         read_lock(&tasklist_lock);
2266         __wake_up_parent(current, current->real_parent);
2267         read_unlock(&tasklist_lock);
2268 }
2269
2270 /* superblock security operations */
2271
2272 static int selinux_sb_alloc_security(struct super_block *sb)
2273 {
2274         return superblock_alloc_security(sb);
2275 }
2276
2277 static void selinux_sb_free_security(struct super_block *sb)
2278 {
2279         superblock_free_security(sb);
2280 }
2281
2282 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2283 {
2284         if (plen > olen)
2285                 return 0;
2286
2287         return !memcmp(prefix, option, plen);
2288 }
2289
2290 static inline int selinux_option(char *option, int len)
2291 {
2292         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2293                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2294                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2295                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2296                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2297 }
2298
2299 static inline void take_option(char **to, char *from, int *first, int len)
2300 {
2301         if (!*first) {
2302                 **to = ',';
2303                 *to += 1;
2304         } else
2305                 *first = 0;
2306         memcpy(*to, from, len);
2307         *to += len;
2308 }
2309
2310 static inline void take_selinux_option(char **to, char *from, int *first,
2311                                        int len)
2312 {
2313         int current_size = 0;
2314
2315         if (!*first) {
2316                 **to = '|';
2317                 *to += 1;
2318         } else
2319                 *first = 0;
2320
2321         while (current_size < len) {
2322                 if (*from != '"') {
2323                         **to = *from;
2324                         *to += 1;
2325                 }
2326                 from += 1;
2327                 current_size += 1;
2328         }
2329 }
2330
2331 static int selinux_sb_copy_data(char *orig, char *copy)
2332 {
2333         int fnosec, fsec, rc = 0;
2334         char *in_save, *in_curr, *in_end;
2335         char *sec_curr, *nosec_save, *nosec;
2336         int open_quote = 0;
2337
2338         in_curr = orig;
2339         sec_curr = copy;
2340
2341         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2342         if (!nosec) {
2343                 rc = -ENOMEM;
2344                 goto out;
2345         }
2346
2347         nosec_save = nosec;
2348         fnosec = fsec = 1;
2349         in_save = in_end = orig;
2350
2351         do {
2352                 if (*in_end == '"')
2353                         open_quote = !open_quote;
2354                 if ((*in_end == ',' && open_quote == 0) ||
2355                                 *in_end == '\0') {
2356                         int len = in_end - in_curr;
2357
2358                         if (selinux_option(in_curr, len))
2359                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2360                         else
2361                                 take_option(&nosec, in_curr, &fnosec, len);
2362
2363                         in_curr = in_end + 1;
2364                 }
2365         } while (*in_end++);
2366
2367         strcpy(in_save, nosec_save);
2368         free_page((unsigned long)nosec_save);
2369 out:
2370         return rc;
2371 }
2372
2373 static int selinux_sb_remount(struct super_block *sb, void *data)
2374 {
2375         int rc, i, *flags;
2376         struct security_mnt_opts opts;
2377         char *secdata, **mount_options;
2378         struct superblock_security_struct *sbsec = sb->s_security;
2379
2380         if (!(sbsec->flags & SE_SBINITIALIZED))
2381                 return 0;
2382
2383         if (!data)
2384                 return 0;
2385
2386         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2387                 return 0;
2388
2389         security_init_mnt_opts(&opts);
2390         secdata = alloc_secdata();
2391         if (!secdata)
2392                 return -ENOMEM;
2393         rc = selinux_sb_copy_data(data, secdata);
2394         if (rc)
2395                 goto out_free_secdata;
2396
2397         rc = selinux_parse_opts_str(secdata, &opts);
2398         if (rc)
2399                 goto out_free_secdata;
2400
2401         mount_options = opts.mnt_opts;
2402         flags = opts.mnt_opts_flags;
2403
2404         for (i = 0; i < opts.num_mnt_opts; i++) {
2405                 u32 sid;
2406                 size_t len;
2407
2408                 if (flags[i] == SE_SBLABELSUPP)
2409                         continue;
2410                 len = strlen(mount_options[i]);
2411                 rc = security_context_to_sid(mount_options[i], len, &sid);
2412                 if (rc) {
2413                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2414                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2415                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2416                         goto out_free_opts;
2417                 }
2418                 rc = -EINVAL;
2419                 switch (flags[i]) {
2420                 case FSCONTEXT_MNT:
2421                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2422                                 goto out_bad_option;
2423                         break;
2424                 case CONTEXT_MNT:
2425                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2426                                 goto out_bad_option;
2427                         break;
2428                 case ROOTCONTEXT_MNT: {
2429                         struct inode_security_struct *root_isec;
2430                         root_isec = sb->s_root->d_inode->i_security;
2431
2432                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2433                                 goto out_bad_option;
2434                         break;
2435                 }
2436                 case DEFCONTEXT_MNT:
2437                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2438                                 goto out_bad_option;
2439                         break;
2440                 default:
2441                         goto out_free_opts;
2442                 }
2443         }
2444
2445         rc = 0;
2446 out_free_opts:
2447         security_free_mnt_opts(&opts);
2448 out_free_secdata:
2449         free_secdata(secdata);
2450         return rc;
2451 out_bad_option:
2452         printk(KERN_WARNING "SELinux: unable to change security options "
2453                "during remount (dev %s, type=%s)\n", sb->s_id,
2454                sb->s_type->name);
2455         goto out_free_opts;
2456 }
2457
2458 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2459 {
2460         const struct cred *cred = current_cred();
2461         struct common_audit_data ad;
2462         int rc;
2463
2464         rc = superblock_doinit(sb, data);
2465         if (rc)
2466                 return rc;
2467
2468         /* Allow all mounts performed by the kernel */
2469         if (flags & MS_KERNMOUNT)
2470                 return 0;
2471
2472         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2473         ad.u.dentry = sb->s_root;
2474         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2475 }
2476
2477 static int selinux_sb_statfs(struct dentry *dentry)
2478 {
2479         const struct cred *cred = current_cred();
2480         struct common_audit_data ad;
2481
2482         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2483         ad.u.dentry = dentry->d_sb->s_root;
2484         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2485 }
2486
2487 static int selinux_mount(char *dev_name,
2488                          struct path *path,
2489                          char *type,
2490                          unsigned long flags,
2491                          void *data)
2492 {
2493         const struct cred *cred = current_cred();
2494
2495         if (flags & MS_REMOUNT)
2496                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2497                                            FILESYSTEM__REMOUNT, NULL);
2498         else
2499                 return dentry_has_perm(cred, path->mnt, path->dentry,
2500                                        FILE__MOUNTON);
2501 }
2502
2503 static int selinux_umount(struct vfsmount *mnt, int flags)
2504 {
2505         const struct cred *cred = current_cred();
2506
2507         return superblock_has_perm(cred, mnt->mnt_sb,
2508                                    FILESYSTEM__UNMOUNT, NULL);
2509 }
2510
2511 /* inode security operations */
2512
2513 static int selinux_inode_alloc_security(struct inode *inode)
2514 {
2515         return inode_alloc_security(inode);
2516 }
2517
2518 static void selinux_inode_free_security(struct inode *inode)
2519 {
2520         inode_free_security(inode);
2521 }
2522
2523 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2524                                        const struct qstr *qstr, char **name,
2525                                        void **value, size_t *len)
2526 {
2527         const struct task_security_struct *tsec = current_security();
2528         struct inode_security_struct *dsec;
2529         struct superblock_security_struct *sbsec;
2530         u32 sid, newsid, clen;
2531         int rc;
2532         char *namep = NULL, *context;
2533
2534         dsec = dir->i_security;
2535         sbsec = dir->i_sb->s_security;
2536
2537         sid = tsec->sid;
2538         newsid = tsec->create_sid;
2539
2540         if ((sbsec->flags & SE_SBINITIALIZED) &&
2541             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2542                 newsid = sbsec->mntpoint_sid;
2543         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2544                 rc = security_transition_sid(sid, dsec->sid,
2545                                              inode_mode_to_security_class(inode->i_mode),
2546                                              qstr, &newsid);
2547                 if (rc) {
2548                         printk(KERN_WARNING "%s:  "
2549                                "security_transition_sid failed, rc=%d (dev=%s "
2550                                "ino=%ld)\n",
2551                                __func__,
2552                                -rc, inode->i_sb->s_id, inode->i_ino);
2553                         return rc;
2554                 }
2555         }
2556
2557         /* Possibly defer initialization to selinux_complete_init. */
2558         if (sbsec->flags & SE_SBINITIALIZED) {
2559                 struct inode_security_struct *isec = inode->i_security;
2560                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2561                 isec->sid = newsid;
2562                 isec->initialized = 1;
2563         }
2564
2565         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2566                 return -EOPNOTSUPP;
2567
2568         if (name) {
2569                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2570                 if (!namep)
2571                         return -ENOMEM;
2572                 *name = namep;
2573         }
2574
2575         if (value && len) {
2576                 rc = security_sid_to_context_force(newsid, &context, &clen);
2577                 if (rc) {
2578                         kfree(namep);
2579                         return rc;
2580                 }
2581                 *value = context;
2582                 *len = clen;
2583         }
2584
2585         return 0;
2586 }
2587
2588 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2589 {
2590         return may_create(dir, dentry, SECCLASS_FILE);
2591 }
2592
2593 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2594 {
2595         return may_link(dir, old_dentry, MAY_LINK);
2596 }
2597
2598 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2599 {
2600         return may_link(dir, dentry, MAY_UNLINK);
2601 }
2602
2603 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2604 {
2605         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2606 }
2607
2608 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2609 {
2610         return may_create(dir, dentry, SECCLASS_DIR);
2611 }
2612
2613 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2614 {
2615         return may_link(dir, dentry, MAY_RMDIR);
2616 }
2617
2618 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2619 {
2620         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2621 }
2622
2623 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2624                                 struct inode *new_inode, struct dentry *new_dentry)
2625 {
2626         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2627 }
2628
2629 static int selinux_inode_readlink(struct dentry *dentry)
2630 {
2631         const struct cred *cred = current_cred();
2632
2633         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2634 }
2635
2636 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2637 {
2638         const struct cred *cred = current_cred();
2639
2640         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2641 }
2642
2643 static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags)
2644 {
2645         const struct cred *cred = current_cred();
2646         struct common_audit_data ad;
2647         u32 perms;
2648         bool from_access;
2649
2650         from_access = mask & MAY_ACCESS;
2651         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2652
2653         /* No permission to check.  Existence test. */
2654         if (!mask)
2655                 return 0;
2656
2657         COMMON_AUDIT_DATA_INIT(&ad, INODE);
2658         ad.u.inode = inode;
2659
2660         if (from_access)
2661                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2662
2663         perms = file_mask_to_av(inode->i_mode, mask);
2664
2665         return inode_has_perm(cred, inode, perms, &ad, flags);
2666 }
2667
2668 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2669 {
2670         const struct cred *cred = current_cred();
2671         unsigned int ia_valid = iattr->ia_valid;
2672
2673         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2674         if (ia_valid & ATTR_FORCE) {
2675                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2676                               ATTR_FORCE);
2677                 if (!ia_valid)
2678                         return 0;
2679         }
2680
2681         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2682                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2683                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2684
2685         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2686 }
2687
2688 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2689 {
2690         const struct cred *cred = current_cred();
2691
2692         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2693 }
2694
2695 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2696 {
2697         const struct cred *cred = current_cred();
2698
2699         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2700                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2701                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2702                         if (!capable(CAP_SETFCAP))
2703                                 return -EPERM;
2704                 } else if (!capable(CAP_SYS_ADMIN)) {
2705                         /* A different attribute in the security namespace.
2706                            Restrict to administrator. */
2707                         return -EPERM;
2708                 }
2709         }
2710
2711         /* Not an attribute we recognize, so just check the
2712            ordinary setattr permission. */
2713         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2714 }
2715
2716 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2717                                   const void *value, size_t size, int flags)
2718 {
2719         struct inode *inode = dentry->d_inode;
2720         struct inode_security_struct *isec = inode->i_security;
2721         struct superblock_security_struct *sbsec;
2722         struct common_audit_data ad;
2723         u32 newsid, sid = current_sid();
2724         int rc = 0;
2725
2726         if (strcmp(name, XATTR_NAME_SELINUX))
2727                 return selinux_inode_setotherxattr(dentry, name);
2728
2729         sbsec = inode->i_sb->s_security;
2730         if (!(sbsec->flags & SE_SBLABELSUPP))
2731                 return -EOPNOTSUPP;
2732
2733         if (!is_owner_or_cap(inode))
2734                 return -EPERM;
2735
2736         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2737         ad.u.dentry = dentry;
2738
2739         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2740                           FILE__RELABELFROM, &ad);
2741         if (rc)
2742                 return rc;
2743
2744         rc = security_context_to_sid(value, size, &newsid);
2745         if (rc == -EINVAL) {
2746                 if (!capable(CAP_MAC_ADMIN))
2747                         return rc;
2748                 rc = security_context_to_sid_force(value, size, &newsid);
2749         }
2750         if (rc)
2751                 return rc;
2752
2753         rc = avc_has_perm(sid, newsid, isec->sclass,
2754                           FILE__RELABELTO, &ad);
2755         if (rc)
2756                 return rc;
2757
2758         rc = security_validate_transition(isec->sid, newsid, sid,
2759                                           isec->sclass);
2760         if (rc)
2761                 return rc;
2762
2763         return avc_has_perm(newsid,
2764                             sbsec->sid,
2765                             SECCLASS_FILESYSTEM,
2766                             FILESYSTEM__ASSOCIATE,
2767                             &ad);
2768 }
2769
2770 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2771                                         const void *value, size_t size,
2772                                         int flags)
2773 {
2774         struct inode *inode = dentry->d_inode;
2775         struct inode_security_struct *isec = inode->i_security;
2776         u32 newsid;
2777         int rc;
2778
2779         if (strcmp(name, XATTR_NAME_SELINUX)) {
2780                 /* Not an attribute we recognize, so nothing to do. */
2781                 return;
2782         }
2783
2784         rc = security_context_to_sid_force(value, size, &newsid);
2785         if (rc) {
2786                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2787                        "for (%s, %lu), rc=%d\n",
2788                        inode->i_sb->s_id, inode->i_ino, -rc);
2789                 return;
2790         }
2791
2792         isec->sid = newsid;
2793         return;
2794 }
2795
2796 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2797 {
2798         const struct cred *cred = current_cred();
2799
2800         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2801 }
2802
2803 static int selinux_inode_listxattr(struct dentry *dentry)
2804 {
2805         const struct cred *cred = current_cred();
2806
2807         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2808 }
2809
2810 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2811 {
2812         if (strcmp(name, XATTR_NAME_SELINUX))
2813                 return selinux_inode_setotherxattr(dentry, name);
2814
2815         /* No one is allowed to remove a SELinux security label.
2816            You can change the label, but all data must be labeled. */
2817         return -EACCES;
2818 }
2819
2820 /*
2821  * Copy the inode security context value to the user.
2822  *
2823  * Permission check is handled by selinux_inode_getxattr hook.
2824  */
2825 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2826 {
2827         u32 size;
2828         int error;
2829         char *context = NULL;
2830         struct inode_security_struct *isec = inode->i_security;
2831
2832         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2833                 return -EOPNOTSUPP;
2834
2835         /*
2836          * If the caller has CAP_MAC_ADMIN, then get the raw context
2837          * value even if it is not defined by current policy; otherwise,
2838          * use the in-core value under current policy.
2839          * Use the non-auditing forms of the permission checks since
2840          * getxattr may be called by unprivileged processes commonly
2841          * and lack of permission just means that we fall back to the
2842          * in-core context value, not a denial.
2843          */
2844         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2845                                 SECURITY_CAP_NOAUDIT);
2846         if (!error)
2847                 error = security_sid_to_context_force(isec->sid, &context,
2848                                                       &size);
2849         else
2850                 error = security_sid_to_context(isec->sid, &context, &size);
2851         if (error)
2852                 return error;
2853         error = size;
2854         if (alloc) {
2855                 *buffer = context;
2856                 goto out_nofree;
2857         }
2858         kfree(context);
2859 out_nofree:
2860         return error;
2861 }
2862
2863 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2864                                      const void *value, size_t size, int flags)
2865 {
2866         struct inode_security_struct *isec = inode->i_security;
2867         u32 newsid;
2868         int rc;
2869
2870         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2871                 return -EOPNOTSUPP;
2872
2873         if (!value || !size)
2874                 return -EACCES;
2875
2876         rc = security_context_to_sid((void *)value, size, &newsid);
2877         if (rc)
2878                 return rc;
2879
2880         isec->sid = newsid;
2881         isec->initialized = 1;
2882         return 0;
2883 }
2884
2885 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2886 {
2887         const int len = sizeof(XATTR_NAME_SELINUX);
2888         if (buffer && len <= buffer_size)
2889                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2890         return len;
2891 }
2892
2893 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2894 {
2895         struct inode_security_struct *isec = inode->i_security;
2896         *secid = isec->sid;
2897 }
2898
2899 /* file security operations */
2900
2901 static int selinux_revalidate_file_permission(struct file *file, int mask)
2902 {
2903         const struct cred *cred = current_cred();
2904         struct inode *inode = file->f_path.dentry->d_inode;
2905
2906         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2907         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2908                 mask |= MAY_APPEND;
2909
2910         return file_has_perm(cred, file,
2911                              file_mask_to_av(inode->i_mode, mask));
2912 }
2913
2914 static int selinux_file_permission(struct file *file, int mask)
2915 {
2916         struct inode *inode = file->f_path.dentry->d_inode;
2917         struct file_security_struct *fsec = file->f_security;
2918         struct inode_security_struct *isec = inode->i_security;
2919         u32 sid = current_sid();
2920
2921         if (!mask)
2922                 /* No permission to check.  Existence test. */
2923                 return 0;
2924
2925         if (sid == fsec->sid && fsec->isid == isec->sid &&
2926             fsec->pseqno == avc_policy_seqno())
2927                 /* No change since dentry_open check. */
2928                 return 0;
2929
2930         return selinux_revalidate_file_permission(file, mask);
2931 }
2932
2933 static int selinux_file_alloc_security(struct file *file)
2934 {
2935         return file_alloc_security(file);
2936 }
2937
2938 static void selinux_file_free_security(struct file *file)
2939 {
2940         file_free_security(file);
2941 }
2942
2943 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2944                               unsigned long arg)
2945 {
2946         const struct cred *cred = current_cred();
2947         int error = 0;
2948
2949         switch (cmd) {
2950         case FIONREAD:
2951         /* fall through */
2952         case FIBMAP:
2953         /* fall through */
2954         case FIGETBSZ:
2955         /* fall through */
2956         case EXT2_IOC_GETFLAGS:
2957         /* fall through */
2958         case EXT2_IOC_GETVERSION:
2959                 error = file_has_perm(cred, file, FILE__GETATTR);
2960                 break;
2961
2962         case EXT2_IOC_SETFLAGS:
2963         /* fall through */
2964         case EXT2_IOC_SETVERSION:
2965                 error = file_has_perm(cred, file, FILE__SETATTR);
2966                 break;
2967
2968         /* sys_ioctl() checks */
2969         case FIONBIO:
2970         /* fall through */
2971         case FIOASYNC:
2972                 error = file_has_perm(cred, file, 0);
2973                 break;
2974
2975         case KDSKBENT:
2976         case KDSKBSENT:
2977                 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
2978                                             SECURITY_CAP_AUDIT);
2979                 break;
2980
2981         /* default case assumes that the command will go
2982          * to the file's ioctl() function.
2983          */
2984         default:
2985                 error = file_has_perm(cred, file, FILE__IOCTL);
2986         }
2987         return error;
2988 }
2989
2990 static int default_noexec;
2991
2992 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2993 {
2994         const struct cred *cred = current_cred();
2995         int rc = 0;
2996
2997         if (default_noexec &&
2998             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2999                 /*
3000                  * We are making executable an anonymous mapping or a
3001                  * private file mapping that will also be writable.
3002                  * This has an additional check.
3003                  */
3004                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3005                 if (rc)
3006                         goto error;
3007         }
3008
3009         if (file) {
3010                 /* read access is always possible with a mapping */
3011                 u32 av = FILE__READ;
3012
3013                 /* write access only matters if the mapping is shared */
3014                 if (shared && (prot & PROT_WRITE))
3015                         av |= FILE__WRITE;
3016
3017                 if (prot & PROT_EXEC)
3018                         av |= FILE__EXECUTE;
3019
3020                 return file_has_perm(cred, file, av);
3021         }
3022
3023 error:
3024         return rc;
3025 }
3026
3027 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3028                              unsigned long prot, unsigned long flags,
3029                              unsigned long addr, unsigned long addr_only)
3030 {
3031         int rc = 0;
3032         u32 sid = current_sid();
3033
3034         /*
3035          * notice that we are intentionally putting the SELinux check before
3036          * the secondary cap_file_mmap check.  This is such a likely attempt
3037          * at bad behaviour/exploit that we always want to get the AVC, even
3038          * if DAC would have also denied the operation.
3039          */
3040         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3041                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3042                                   MEMPROTECT__MMAP_ZERO, NULL);
3043                 if (rc)
3044                         return rc;
3045         }
3046
3047         /* do DAC check on address space usage */
3048         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3049         if (rc || addr_only)
3050                 return rc;
3051
3052         if (selinux_checkreqprot)
3053                 prot = reqprot;
3054
3055         return file_map_prot_check(file, prot,
3056                                    (flags & MAP_TYPE) == MAP_SHARED);
3057 }
3058
3059 static int selinux_file_mprotect(struct vm_area_struct *vma,
3060                                  unsigned long reqprot,
3061                                  unsigned long prot)
3062 {
3063         const struct cred *cred = current_cred();
3064
3065         if (selinux_checkreqprot)
3066                 prot = reqprot;
3067
3068         if (default_noexec &&
3069             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3070                 int rc = 0;
3071                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3072                     vma->vm_end <= vma->vm_mm->brk) {
3073                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3074                 } else if (!vma->vm_file &&
3075                            vma->vm_start <= vma->vm_mm->start_stack &&
3076                            vma->vm_end >= vma->vm_mm->start_stack) {
3077                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3078                 } else if (vma->vm_file && vma->anon_vma) {
3079                         /*
3080                          * We are making executable a file mapping that has
3081                          * had some COW done. Since pages might have been
3082                          * written, check ability to execute the possibly
3083                          * modified content.  This typically should only
3084                          * occur for text relocations.
3085                          */
3086                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3087                 }
3088                 if (rc)
3089                         return rc;
3090         }
3091
3092         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3093 }
3094
3095 static int selinux_file_lock(struct file *file, unsigned int cmd)
3096 {
3097         const struct cred *cred = current_cred();
3098
3099         return file_has_perm(cred, file, FILE__LOCK);
3100 }
3101
3102 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3103                               unsigned long arg)
3104 {
3105         const struct cred *cred = current_cred();
3106         int err = 0;
3107
3108         switch (cmd) {
3109         case F_SETFL:
3110                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3111                         err = -EINVAL;
3112                         break;
3113                 }
3114
3115                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3116                         err = file_has_perm(cred, file, FILE__WRITE);
3117                         break;
3118                 }
3119                 /* fall through */
3120         case F_SETOWN:
3121         case F_SETSIG:
3122         case F_GETFL:
3123         case F_GETOWN:
3124         case F_GETSIG:
3125                 /* Just check FD__USE permission */
3126                 err = file_has_perm(cred, file, 0);
3127                 break;
3128         case F_GETLK:
3129         case F_SETLK:
3130         case F_SETLKW:
3131 #if BITS_PER_LONG == 32
3132         case F_GETLK64:
3133         case F_SETLK64:
3134         case F_SETLKW64:
3135 #endif
3136                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3137                         err = -EINVAL;
3138                         break;
3139                 }
3140                 err = file_has_perm(cred, file, FILE__LOCK);
3141                 break;
3142         }
3143
3144         return err;
3145 }
3146
3147 static int selinux_file_set_fowner(struct file *file)
3148 {
3149         struct file_security_struct *fsec;
3150
3151         fsec = file->f_security;
3152         fsec->fown_sid = current_sid();
3153
3154         return 0;
3155 }
3156
3157 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3158                                        struct fown_struct *fown, int signum)
3159 {
3160         struct file *file;
3161         u32 sid = task_sid(tsk);
3162         u32 perm;
3163         struct file_security_struct *fsec;
3164
3165         /* struct fown_struct is never outside the context of a struct file */
3166         file = container_of(fown, struct file, f_owner);
3167
3168         fsec = file->f_security;
3169
3170         if (!signum)
3171                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3172         else
3173                 perm = signal_to_av(signum);
3174
3175         return avc_has_perm(fsec->fown_sid, sid,
3176                             SECCLASS_PROCESS, perm, NULL);
3177 }
3178
3179 static int selinux_file_receive(struct file *file)
3180 {
3181         const struct cred *cred = current_cred();
3182
3183         return file_has_perm(cred, file, file_to_av(file));
3184 }
3185
3186 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3187 {
3188         struct file_security_struct *fsec;
3189         struct inode *inode;
3190         struct inode_security_struct *isec;
3191
3192         inode = file->f_path.dentry->d_inode;
3193         fsec = file->f_security;
3194         isec = inode->i_security;
3195         /*
3196          * Save inode label and policy sequence number
3197          * at open-time so that selinux_file_permission
3198          * can determine whether revalidation is necessary.
3199          * Task label is already saved in the file security
3200          * struct as its SID.
3201          */
3202         fsec->isid = isec->sid;
3203         fsec->pseqno = avc_policy_seqno();
3204         /*
3205          * Since the inode label or policy seqno may have changed
3206          * between the selinux_inode_permission check and the saving
3207          * of state above, recheck that access is still permitted.
3208          * Otherwise, access might never be revalidated against the
3209          * new inode label or new policy.
3210          * This check is not redundant - do not remove.
3211          */
3212         return inode_has_perm(cred, inode, open_file_to_av(file), NULL, 0);
3213 }
3214
3215 /* task security operations */
3216
3217 static int selinux_task_create(unsigned long clone_flags)
3218 {
3219         return current_has_perm(current, PROCESS__FORK);
3220 }
3221
3222 /*
3223  * allocate the SELinux part of blank credentials
3224  */
3225 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3226 {
3227         struct task_security_struct *tsec;
3228
3229         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3230         if (!tsec)
3231                 return -ENOMEM;
3232
3233         cred->security = tsec;
3234         return 0;
3235 }
3236
3237 /*
3238  * detach and free the LSM part of a set of credentials
3239  */
3240 static void selinux_cred_free(struct cred *cred)
3241 {
3242         struct task_security_struct *tsec = cred->security;
3243
3244         /*
3245          * cred->security == NULL if security_cred_alloc_blank() or
3246          * security_prepare_creds() returned an error.
3247          */
3248         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3249         cred->security = (void *) 0x7UL;
3250         kfree(tsec);
3251 }
3252
3253 /*
3254  * prepare a new set of credentials for modification
3255  */
3256 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3257                                 gfp_t gfp)
3258 {
3259         const struct task_security_struct *old_tsec;
3260         struct task_security_struct *tsec;
3261
3262         old_tsec = old->security;
3263
3264         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3265         if (!tsec)
3266                 return -ENOMEM;
3267
3268         new->security = tsec;
3269         return 0;
3270 }
3271
3272 /*
3273  * transfer the SELinux data to a blank set of creds
3274  */
3275 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3276 {
3277         const struct task_security_struct *old_tsec = old->security;
3278         struct task_security_struct *tsec = new->security;
3279
3280         *tsec = *old_tsec;
3281 }
3282
3283 /*
3284  * set the security data for a kernel service
3285  * - all the creation contexts are set to unlabelled
3286  */
3287 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3288 {
3289         struct task_security_struct *tsec = new->security;
3290         u32 sid = current_sid();
3291         int ret;
3292
3293         ret = avc_has_perm(sid, secid,
3294                            SECCLASS_KERNEL_SERVICE,
3295                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3296                            NULL);
3297         if (ret == 0) {
3298                 tsec->sid = secid;
3299                 tsec->create_sid = 0;
3300                 tsec->keycreate_sid = 0;
3301                 tsec->sockcreate_sid = 0;
3302         }
3303         return ret;
3304 }
3305
3306 /*
3307  * set the file creation context in a security record to the same as the
3308  * objective context of the specified inode
3309  */
3310 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3311 {
3312         struct inode_security_struct *isec = inode->i_security;
3313         struct task_security_struct *tsec = new->security;
3314         u32 sid = current_sid();
3315         int ret;
3316
3317         ret = avc_has_perm(sid, isec->sid,
3318                            SECCLASS_KERNEL_SERVICE,
3319                            KERNEL_SERVICE__CREATE_FILES_AS,
3320                            NULL);
3321
3322         if (ret == 0)
3323                 tsec->create_sid = isec->sid;
3324         return ret;
3325 }
3326
3327 static int selinux_kernel_module_request(char *kmod_name)
3328 {
3329         u32 sid;
3330         struct common_audit_data ad;
3331
3332         sid = task_sid(current);
3333
3334         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3335         ad.u.kmod_name = kmod_name;
3336
3337         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3338                             SYSTEM__MODULE_REQUEST, &ad);
3339 }
3340
3341 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3342 {
3343         return current_has_perm(p, PROCESS__SETPGID);
3344 }
3345
3346 static int selinux_task_getpgid(struct task_struct *p)
3347 {
3348         return current_has_perm(p, PROCESS__GETPGID);
3349 }
3350
3351 static int selinux_task_getsid(struct task_struct *p)
3352 {
3353         return current_has_perm(p, PROCESS__GETSESSION);
3354 }
3355
3356 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3357 {
3358         *secid = task_sid(p);
3359 }
3360
3361 static int selinux_task_setnice(struct task_struct *p, int nice)
3362 {
3363         int rc;
3364
3365         rc = cap_task_setnice(p, nice);
3366         if (rc)
3367                 return rc;
3368
3369         return current_has_perm(p, PROCESS__SETSCHED);
3370 }
3371
3372 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3373 {
3374         int rc;
3375
3376         rc = cap_task_setioprio(p, ioprio);
3377         if (rc)
3378                 return rc;
3379
3380         return current_has_perm(p, PROCESS__SETSCHED);
3381 }
3382
3383 static int selinux_task_getioprio(struct task_struct *p)
3384 {
3385         return current_has_perm(p, PROCESS__GETSCHED);
3386 }
3387
3388 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3389                 struct rlimit *new_rlim)
3390 {
3391         struct rlimit *old_rlim = p->signal->rlim + resource;
3392
3393         /* Control the ability to change the hard limit (whether
3394            lowering or raising it), so that the hard limit can
3395            later be used as a safe reset point for the soft limit
3396            upon context transitions.  See selinux_bprm_committing_creds. */
3397         if (old_rlim->rlim_max != new_rlim->rlim_max)
3398                 return current_has_perm(p, PROCESS__SETRLIMIT);
3399
3400         return 0;
3401 }
3402
3403 static int selinux_task_setscheduler(struct task_struct *p)
3404 {
3405         int rc;
3406
3407         rc = cap_task_setscheduler(p);
3408         if (rc)
3409                 return rc;
3410
3411         return current_has_perm(p, PROCESS__SETSCHED);
3412 }
3413
3414 static int selinux_task_getscheduler(struct task_struct *p)
3415 {
3416         return current_has_perm(p, PROCESS__GETSCHED);
3417 }
3418
3419 static int selinux_task_movememory(struct task_struct *p)
3420 {
3421         return current_has_perm(p, PROCESS__SETSCHED);
3422 }
3423
3424 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3425                                 int sig, u32 secid)
3426 {
3427         u32 perm;
3428         int rc;
3429
3430         if (!sig)
3431                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3432         else
3433                 perm = signal_to_av(sig);
3434         if (secid)
3435                 rc = avc_has_perm(secid, task_sid(p),
3436                                   SECCLASS_PROCESS, perm, NULL);
3437         else
3438                 rc = current_has_perm(p, perm);
3439         return rc;
3440 }
3441
3442 static int selinux_task_wait(struct task_struct *p)
3443 {
3444         return task_has_perm(p, current, PROCESS__SIGCHLD);
3445 }
3446
3447 static void selinux_task_to_inode(struct task_struct *p,
3448                                   struct inode *inode)
3449 {
3450         struct inode_security_struct *isec = inode->i_security;
3451         u32 sid = task_sid(p);
3452
3453         isec->sid = sid;
3454         isec->initialized = 1;
3455 }
3456
3457 /* Returns error only if unable to parse addresses */
3458 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3459                         struct common_audit_data *ad, u8 *proto)
3460 {
3461         int offset, ihlen, ret = -EINVAL;
3462         struct iphdr _iph, *ih;
3463
3464         offset = skb_network_offset(skb);
3465         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3466         if (ih == NULL)
3467                 goto out;
3468
3469         ihlen = ih->ihl * 4;
3470         if (ihlen < sizeof(_iph))
3471                 goto out;
3472
3473         ad->u.net.v4info.saddr = ih->saddr;
3474         ad->u.net.v4info.daddr = ih->daddr;
3475         ret = 0;
3476
3477         if (proto)
3478                 *proto = ih->protocol;
3479
3480         switch (ih->protocol) {
3481         case IPPROTO_TCP: {
3482                 struct tcphdr _tcph, *th;
3483
3484                 if (ntohs(ih->frag_off) & IP_OFFSET)
3485                         break;
3486
3487                 offset += ihlen;
3488                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3489                 if (th == NULL)
3490                         break;
3491
3492                 ad->u.net.sport = th->source;
3493                 ad->u.net.dport = th->dest;
3494                 break;
3495         }
3496
3497         case IPPROTO_UDP: {
3498                 struct udphdr _udph, *uh;
3499
3500                 if (ntohs(ih->frag_off) & IP_OFFSET)
3501                         break;
3502
3503                 offset += ihlen;
3504                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3505                 if (uh == NULL)
3506                         break;
3507
3508                 ad->u.net.sport = uh->source;
3509                 ad->u.net.dport = uh->dest;
3510                 break;
3511         }
3512
3513         case IPPROTO_DCCP: {
3514                 struct dccp_hdr _dccph, *dh;
3515
3516                 if (ntohs(ih->frag_off) & IP_OFFSET)
3517                         break;
3518
3519                 offset += ihlen;
3520                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3521                 if (dh == NULL)
3522                         break;
3523
3524                 ad->u.net.sport = dh->dccph_sport;
3525                 ad->u.net.dport = dh->dccph_dport;
3526                 break;
3527         }
3528
3529         default:
3530                 break;
3531         }
3532 out:
3533         return ret;
3534 }
3535
3536 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3537
3538 /* Returns error only if unable to parse addresses */
3539 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3540                         struct common_audit_data *ad, u8 *proto)
3541 {
3542         u8 nexthdr;
3543         int ret = -EINVAL, offset;
3544         struct ipv6hdr _ipv6h, *ip6;
3545
3546         offset = skb_network_offset(skb);
3547         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3548         if (ip6 == NULL)
3549                 goto out;
3550
3551         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3552         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3553         ret = 0;
3554
3555         nexthdr = ip6->nexthdr;
3556         offset += sizeof(_ipv6h);
3557         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3558         if (offset < 0)
3559                 goto out;
3560
3561         if (proto)
3562                 *proto = nexthdr;
3563
3564         switch (nexthdr) {
3565         case IPPROTO_TCP: {
3566                 struct tcphdr _tcph, *th;
3567
3568                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3569                 if (th == NULL)
3570                         break;
3571
3572                 ad->u.net.sport = th->source;
3573                 ad->u.net.dport = th->dest;
3574                 break;
3575         }
3576
3577         case IPPROTO_UDP: {
3578                 struct udphdr _udph, *uh;
3579
3580                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3581                 if (uh == NULL)
3582                         break;
3583
3584                 ad->u.net.sport = uh->source;
3585                 ad->u.net.dport = uh->dest;
3586                 break;
3587         }
3588
3589         case IPPROTO_DCCP: {
3590                 struct dccp_hdr _dccph, *dh;
3591
3592                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3593                 if (dh == NULL)
3594                         break;
3595
3596                 ad->u.net.sport = dh->dccph_sport;
3597                 ad->u.net.dport = dh->dccph_dport;
3598                 break;
3599         }
3600
3601         /* includes fragments */
3602         default:
3603                 break;
3604         }
3605 out:
3606         return ret;
3607 }
3608
3609 #endif /* IPV6 */
3610
3611 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3612                              char **_addrp, int src, u8 *proto)
3613 {
3614         char *addrp;
3615         int ret;
3616
3617         switch (ad->u.net.family) {
3618         case PF_INET:
3619                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3620                 if (ret)
3621                         goto parse_error;
3622                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3623                                        &ad->u.net.v4info.daddr);
3624                 goto okay;
3625
3626 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3627         case PF_INET6:
3628                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3629                 if (ret)
3630                         goto parse_error;
3631                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3632                                        &ad->u.net.v6info.daddr);
3633                 goto okay;
3634 #endif  /* IPV6 */
3635         default:
3636                 addrp = NULL;
3637                 goto okay;
3638         }
3639
3640 parse_error:
3641         printk(KERN_WARNING
3642                "SELinux: failure in selinux_parse_skb(),"
3643                " unable to parse packet\n");
3644         return ret;
3645
3646 okay:
3647         if (_addrp)
3648                 *_addrp = addrp;
3649         return 0;
3650 }
3651
3652 /**
3653  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3654  * @skb: the packet
3655  * @family: protocol family
3656  * @sid: the packet's peer label SID
3657  *
3658  * Description:
3659  * Check the various different forms of network peer labeling and determine
3660  * the peer label/SID for the packet; most of the magic actually occurs in
3661  * the security server function security_net_peersid_cmp().  The function
3662  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3663  * or -EACCES if @sid is invalid due to inconsistencies with the different
3664  * peer labels.
3665  *
3666  */
3667 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3668 {
3669         int err;
3670         u32 xfrm_sid;
3671         u32 nlbl_sid;
3672         u32 nlbl_type;
3673
3674         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3675         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3676
3677         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3678         if (unlikely(err)) {
3679                 printk(KERN_WARNING
3680                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3681                        " unable to determine packet's peer label\n");
3682                 return -EACCES;
3683         }
3684
3685         return 0;
3686 }
3687
3688 /* socket security operations */
3689
3690 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3691                                  u16 secclass, u32 *socksid)
3692 {
3693         if (tsec->sockcreate_sid > SECSID_NULL) {
3694                 *socksid = tsec->sockcreate_sid;
3695                 return 0;
3696         }
3697
3698         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3699                                        socksid);
3700 }
3701
3702 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3703 {
3704         struct sk_security_struct *sksec = sk->sk_security;
3705         struct common_audit_data ad;
3706         u32 tsid = task_sid(task);
3707
3708         if (sksec->sid == SECINITSID_KERNEL)
3709                 return 0;
3710
3711         COMMON_AUDIT_DATA_INIT(&ad, NET);
3712         ad.u.net.sk = sk;
3713
3714         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3715 }
3716
3717 static int selinux_socket_create(int family, int type,
3718                                  int protocol, int kern)
3719 {
3720         const struct task_security_struct *tsec = current_security();
3721         u32 newsid;
3722         u16 secclass;
3723         int rc;
3724
3725         if (kern)
3726                 return 0;
3727
3728         secclass = socket_type_to_security_class(family, type, protocol);
3729         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3730         if (rc)
3731                 return rc;
3732
3733         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3734 }
3735
3736 static int selinux_socket_post_create(struct socket *sock, int family,
3737                                       int type, int protocol, int kern)
3738 {
3739         const struct task_security_struct *tsec = current_security();
3740         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3741         struct sk_security_struct *sksec;
3742         int err = 0;
3743
3744         isec->sclass = socket_type_to_security_class(family, type, protocol);
3745
3746         if (kern)
3747                 isec->sid = SECINITSID_KERNEL;
3748         else {
3749                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3750                 if (err)
3751                         return err;
3752         }
3753
3754         isec->initialized = 1;
3755
3756         if (sock->sk) {
3757                 sksec = sock->sk->sk_security;
3758                 sksec->sid = isec->sid;
3759                 sksec->sclass = isec->sclass;
3760                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3761         }
3762
3763         return err;
3764 }
3765
3766 /* Range of port numbers used to automatically bind.
3767    Need to determine whether we should perform a name_bind
3768    permission check between the socket and the port number. */
3769
3770 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3771 {
3772         struct sock *sk = sock->sk;
3773         u16 family;
3774         int err;
3775
3776         err = sock_has_perm(current, sk, SOCKET__BIND);
3777         if (err)
3778                 goto out;
3779
3780         /*
3781          * If PF_INET or PF_INET6, check name_bind permission for the port.
3782          * Multiple address binding for SCTP is not supported yet: we just
3783          * check the first address now.
3784          */
3785         family = sk->sk_family;
3786         if (family == PF_INET || family == PF_INET6) {
3787                 char *addrp;
3788                 struct sk_security_struct *sksec = sk->sk_security;
3789                 struct common_audit_data ad;
3790                 struct sockaddr_in *addr4 = NULL;
3791                 struct sockaddr_in6 *addr6 = NULL;
3792                 unsigned short snum;
3793                 u32 sid, node_perm;
3794
3795                 if (family == PF_INET) {
3796                         addr4 = (struct sockaddr_in *)address;
3797                         snum = ntohs(addr4->sin_port);
3798                         addrp = (char *)&addr4->sin_addr.s_addr;
3799                 } else {
3800                         addr6 = (struct sockaddr_in6 *)address;
3801                         snum = ntohs(addr6->sin6_port);
3802                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3803                 }
3804
3805                 if (snum) {
3806                         int low, high;
3807
3808                         inet_get_local_port_range(&low, &high);
3809
3810                         if (snum < max(PROT_SOCK, low) || snum > high) {
3811                                 err = sel_netport_sid(sk->sk_protocol,
3812                                                       snum, &sid);
3813                                 if (err)
3814                                         goto out;
3815                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3816                                 ad.u.net.sport = htons(snum);
3817                                 ad.u.net.family = family;
3818                                 err = avc_has_perm(sksec->sid, sid,
3819                                                    sksec->sclass,
3820                                                    SOCKET__NAME_BIND, &ad);
3821                                 if (err)
3822                                         goto out;
3823                         }
3824                 }
3825
3826                 switch (sksec->sclass) {
3827                 case SECCLASS_TCP_SOCKET:
3828                         node_perm = TCP_SOCKET__NODE_BIND;
3829                         break;
3830
3831                 case SECCLASS_UDP_SOCKET:
3832                         node_perm = UDP_SOCKET__NODE_BIND;
3833                         break;
3834
3835                 case SECCLASS_DCCP_SOCKET:
3836                         node_perm = DCCP_SOCKET__NODE_BIND;
3837                         break;
3838
3839                 default:
3840                         node_perm = RAWIP_SOCKET__NODE_BIND;
3841                         break;
3842                 }
3843
3844                 err = sel_netnode_sid(addrp, family, &sid);
3845                 if (err)
3846                         goto out;
3847
3848                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3849                 ad.u.net.sport = htons(snum);
3850                 ad.u.net.family = family;
3851
3852                 if (family == PF_INET)
3853                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3854                 else
3855                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3856
3857                 err = avc_has_perm(sksec->sid, sid,
3858                                    sksec->sclass, node_perm, &ad);
3859                 if (err)
3860                         goto out;
3861         }
3862 out:
3863         return err;
3864 }
3865
3866 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3867 {
3868         struct sock *sk = sock->sk;
3869         struct sk_security_struct *sksec = sk->sk_security;
3870         int err;
3871
3872         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3873         if (err)
3874                 return err;
3875
3876         /*
3877          * If a TCP or DCCP socket, check name_connect permission for the port.
3878          */
3879         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3880             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3881                 struct common_audit_data ad;
3882                 struct sockaddr_in *addr4 = NULL;
3883                 struct sockaddr_in6 *addr6 = NULL;
3884                 unsigned short snum;
3885                 u32 sid, perm;
3886
3887                 if (sk->sk_family == PF_INET) {
3888                         addr4 = (struct sockaddr_in *)address;
3889                         if (addrlen < sizeof(struct sockaddr_in))
3890                                 return -EINVAL;
3891                         snum = ntohs(addr4->sin_port);
3892                 } else {
3893                         addr6 = (struct sockaddr_in6 *)address;
3894                         if (addrlen < SIN6_LEN_RFC2133)
3895                                 return -EINVAL;
3896                         snum = ntohs(addr6->sin6_port);
3897                 }
3898
3899                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3900                 if (err)
3901                         goto out;
3902
3903                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3904                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3905
3906                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3907                 ad.u.net.dport = htons(snum);
3908                 ad.u.net.family = sk->sk_family;
3909                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3910                 if (err)
3911                         goto out;
3912         }
3913
3914         err = selinux_netlbl_socket_connect(sk, address);
3915
3916 out:
3917         return err;
3918 }
3919
3920 static int selinux_socket_listen(struct socket *sock, int backlog)
3921 {
3922         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3923 }
3924
3925 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3926 {
3927         int err;
3928         struct inode_security_struct *isec;
3929         struct inode_security_struct *newisec;
3930
3931         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3932         if (err)
3933                 return err;
3934
3935         newisec = SOCK_INODE(newsock)->i_security;
3936
3937         isec = SOCK_INODE(sock)->i_security;
3938         newisec->sclass = isec->sclass;
3939         newisec->sid = isec->sid;
3940         newisec->initialized = 1;
3941
3942         return 0;
3943 }
3944
3945 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3946                                   int size)
3947 {
3948         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3949 }
3950
3951 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3952                                   int size, int flags)
3953 {
3954         return sock_has_perm(current, sock->sk, SOCKET__READ);
3955 }
3956
3957 static int selinux_socket_getsockname(struct socket *sock)
3958 {
3959         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3960 }
3961
3962 static int selinux_socket_getpeername(struct socket *sock)
3963 {
3964         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3965 }
3966
3967 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3968 {
3969         int err;
3970
3971         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3972         if (err)
3973                 return err;
3974
3975         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3976 }
3977
3978 static int selinux_socket_getsockopt(struct socket *sock, int level,
3979                                      int optname)
3980 {
3981         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3982 }
3983
3984 static int selinux_socket_shutdown(struct socket *sock, int how)
3985 {
3986         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3987 }
3988
3989 static int selinux_socket_unix_stream_connect(struct sock *sock,
3990                                               struct sock *other,
3991                                               struct sock *newsk)
3992 {
3993         struct sk_security_struct *sksec_sock = sock->sk_security;
3994         struct sk_security_struct *sksec_other = other->sk_security;
3995         struct sk_security_struct *sksec_new = newsk->sk_security;
3996         struct common_audit_data ad;
3997         int err;
3998
3999         COMMON_AUDIT_DATA_INIT(&ad, NET);
4000         ad.u.net.sk = other;
4001
4002         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4003                            sksec_other->sclass,
4004                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4005         if (err)
4006                 return err;
4007
4008         /* server child socket */
4009         sksec_new->peer_sid = sksec_sock->sid;
4010         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4011                                     &sksec_new->sid);
4012         if (err)
4013                 return err;
4014
4015         /* connecting socket */
4016         sksec_sock->peer_sid = sksec_new->sid;
4017
4018         return 0;
4019 }
4020
4021 static int selinux_socket_unix_may_send(struct socket *sock,
4022                                         struct socket *other)
4023 {
4024         struct sk_security_struct *ssec = sock->sk->sk_security;
4025         struct sk_security_struct *osec = other->sk->sk_security;
4026         struct common_audit_data ad;
4027
4028         COMMON_AUDIT_DATA_INIT(&ad, NET);
4029         ad.u.net.sk = other->sk;
4030
4031         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4032                             &ad);
4033 }
4034
4035 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4036                                     u32 peer_sid,
4037                                     struct common_audit_data *ad)
4038 {
4039         int err;
4040         u32 if_sid;
4041         u32 node_sid;
4042
4043         err = sel_netif_sid(ifindex, &if_sid);
4044         if (err)
4045                 return err;
4046         err = avc_has_perm(peer_sid, if_sid,
4047                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4048         if (err)
4049                 return err;
4050
4051         err = sel_netnode_sid(addrp, family, &node_sid);
4052         if (err)
4053                 return err;
4054         return avc_has_perm(peer_sid, node_sid,
4055                             SECCLASS_NODE, NODE__RECVFROM, ad);
4056 }
4057
4058 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4059                                        u16 family)
4060 {
4061         int err = 0;
4062         struct sk_security_struct *sksec = sk->sk_security;
4063         u32 sk_sid = sksec->sid;
4064         struct common_audit_data ad;
4065         char *addrp;
4066
4067         COMMON_AUDIT_DATA_INIT(&ad, NET);
4068         ad.u.net.netif = skb->skb_iif;
4069         ad.u.net.family = family;
4070         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4071         if (err)
4072                 return err;
4073
4074         if (selinux_secmark_enabled()) {
4075                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4076                                    PACKET__RECV, &ad);
4077                 if (err)
4078                         return err;
4079         }
4080
4081         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4082         if (err)
4083                 return err;
4084         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4085
4086         return err;
4087 }
4088
4089 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4090 {
4091         int err;
4092         struct sk_security_struct *sksec = sk->sk_security;
4093         u16 family = sk->sk_family;
4094         u32 sk_sid = sksec->sid;
4095         struct common_audit_data ad;
4096         char *addrp;
4097         u8 secmark_active;
4098         u8 peerlbl_active;
4099
4100         if (family != PF_INET && family != PF_INET6)
4101                 return 0;
4102
4103         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4104         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4105                 family = PF_INET;
4106
4107         /* If any sort of compatibility mode is enabled then handoff processing
4108          * to the selinux_sock_rcv_skb_compat() function to deal with the
4109          * special handling.  We do this in an attempt to keep this function
4110          * as fast and as clean as possible. */
4111         if (!selinux_policycap_netpeer)
4112                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4113
4114         secmark_active = selinux_secmark_enabled();
4115         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4116         if (!secmark_active && !peerlbl_active)
4117                 return 0;
4118
4119         COMMON_AUDIT_DATA_INIT(&ad, NET);
4120         ad.u.net.netif = skb->skb_iif;
4121         ad.u.net.family = family;
4122         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4123         if (err)
4124                 return err;
4125
4126         if (peerlbl_active) {
4127                 u32 peer_sid;
4128
4129                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4130                 if (err)
4131                         return err;
4132                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4133                                                peer_sid, &ad);
4134                 if (err) {
4135                         selinux_netlbl_err(skb, err, 0);
4136                         return err;
4137                 }
4138                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4139                                    PEER__RECV, &ad);
4140                 if (err)
4141                         selinux_netlbl_err(skb, err, 0);
4142         }
4143
4144         if (secmark_active) {
4145                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4146                                    PACKET__RECV, &ad);
4147                 if (err)
4148                         return err;
4149         }
4150
4151         return err;
4152 }
4153
4154 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4155                                             int __user *optlen, unsigned len)
4156 {
4157         int err = 0;
4158         char *scontext;
4159         u32 scontext_len;
4160         struct sk_security_struct *sksec = sock->sk->sk_security;
4161         u32 peer_sid = SECSID_NULL;
4162
4163         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4164             sksec->sclass == SECCLASS_TCP_SOCKET)
4165                 peer_sid = sksec->peer_sid;
4166         if (peer_sid == SECSID_NULL)
4167                 return -ENOPROTOOPT;
4168
4169         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4170         if (err)
4171                 return err;
4172
4173         if (scontext_len > len) {
4174                 err = -ERANGE;
4175                 goto out_len;
4176         }
4177
4178         if (copy_to_user(optval, scontext, scontext_len))
4179                 err = -EFAULT;
4180
4181 out_len:
4182         if (put_user(scontext_len, optlen))
4183                 err = -EFAULT;
4184         kfree(scontext);
4185         return err;
4186 }
4187
4188 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4189 {
4190         u32 peer_secid = SECSID_NULL;
4191         u16 family;
4192
4193         if (skb && skb->protocol == htons(ETH_P_IP))
4194                 family = PF_INET;
4195         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4196                 family = PF_INET6;
4197         else if (sock)
4198                 family = sock->sk->sk_family;
4199         else
4200                 goto out;
4201
4202         if (sock && family == PF_UNIX)
4203                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4204         else if (skb)
4205                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4206
4207 out:
4208         *secid = peer_secid;
4209         if (peer_secid == SECSID_NULL)
4210                 return -EINVAL;
4211         return 0;
4212 }
4213
4214 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4215 {
4216         struct sk_security_struct *sksec;
4217
4218         sksec = kzalloc(sizeof(*sksec), priority);
4219         if (!sksec)
4220                 return -ENOMEM;
4221
4222         sksec->peer_sid = SECINITSID_UNLABELED;
4223         sksec->sid = SECINITSID_UNLABELED;
4224         selinux_netlbl_sk_security_reset(sksec);
4225         sk->sk_security = sksec;
4226
4227         return 0;
4228 }
4229
4230 static void selinux_sk_free_security(struct sock *sk)
4231 {
4232         struct sk_security_struct *sksec = sk->sk_security;
4233
4234         sk->sk_security = NULL;
4235         selinux_netlbl_sk_security_free(sksec);
4236         kfree(sksec);
4237 }
4238
4239 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4240 {
4241         struct sk_security_struct *sksec = sk->sk_security;
4242         struct sk_security_struct *newsksec = newsk->sk_security;
4243
4244         newsksec->sid = sksec->sid;
4245         newsksec->peer_sid = sksec->peer_sid;
4246         newsksec->sclass = sksec->sclass;
4247
4248         selinux_netlbl_sk_security_reset(newsksec);
4249 }
4250
4251 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4252 {
4253         if (!sk)
4254                 *secid = SECINITSID_ANY_SOCKET;
4255         else {
4256                 struct sk_security_struct *sksec = sk->sk_security;
4257
4258                 *secid = sksec->sid;
4259         }
4260 }
4261
4262 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4263 {
4264         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4265         struct sk_security_struct *sksec = sk->sk_security;
4266
4267         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4268             sk->sk_family == PF_UNIX)
4269                 isec->sid = sksec->sid;
4270         sksec->sclass = isec->sclass;
4271 }
4272
4273 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4274                                      struct request_sock *req)
4275 {
4276         struct sk_security_struct *sksec = sk->sk_security;
4277         int err;
4278         u16 family = sk->sk_family;
4279         u32 newsid;
4280         u32 peersid;
4281
4282         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4283         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4284                 family = PF_INET;
4285
4286         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4287         if (err)
4288                 return err;
4289         if (peersid == SECSID_NULL) {
4290                 req->secid = sksec->sid;
4291                 req->peer_secid = SECSID_NULL;
4292         } else {
4293                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4294                 if (err)
4295                         return err;
4296                 req->secid = newsid;
4297                 req->peer_secid = peersid;
4298         }
4299
4300         return selinux_netlbl_inet_conn_request(req, family);
4301 }
4302
4303 static void selinux_inet_csk_clone(struct sock *newsk,
4304                                    const struct request_sock *req)
4305 {
4306         struct sk_security_struct *newsksec = newsk->sk_security;
4307
4308         newsksec->sid = req->secid;
4309         newsksec->peer_sid = req->peer_secid;
4310         /* NOTE: Ideally, we should also get the isec->sid for the
4311            new socket in sync, but we don't have the isec available yet.
4312            So we will wait until sock_graft to do it, by which
4313            time it will have been created and available. */
4314
4315         /* We don't need to take any sort of lock here as we are the only
4316          * thread with access to newsksec */
4317         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4318 }
4319
4320 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4321 {
4322         u16 family = sk->sk_family;
4323         struct sk_security_struct *sksec = sk->sk_security;
4324
4325         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4326         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4327                 family = PF_INET;
4328
4329         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4330 }
4331
4332 static int selinux_secmark_relabel_packet(u32 sid)
4333 {
4334         const struct task_security_struct *__tsec;
4335         u32 tsid;
4336
4337         __tsec = current_security();
4338         tsid = __tsec->sid;
4339
4340         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4341 }
4342
4343 static void selinux_secmark_refcount_inc(void)
4344 {
4345         atomic_inc(&selinux_secmark_refcount);
4346 }
4347
4348 static void selinux_secmark_refcount_dec(void)
4349 {
4350         atomic_dec(&selinux_secmark_refcount);
4351 }
4352
4353 static void selinux_req_classify_flow(const struct request_sock *req,
4354                                       struct flowi *fl)
4355 {
4356         fl->secid = req->secid;
4357 }
4358
4359 static int selinux_tun_dev_create(void)
4360 {
4361         u32 sid = current_sid();
4362
4363         /* we aren't taking into account the "sockcreate" SID since the socket
4364          * that is being created here is not a socket in the traditional sense,
4365          * instead it is a private sock, accessible only to the kernel, and
4366          * representing a wide range of network traffic spanning multiple
4367          * connections unlike traditional sockets - check the TUN driver to
4368          * get a better understanding of why this socket is special */
4369
4370         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4371                             NULL);
4372 }
4373
4374 static void selinux_tun_dev_post_create(struct sock *sk)
4375 {
4376         struct sk_security_struct *sksec = sk->sk_security;
4377
4378         /* we don't currently perform any NetLabel based labeling here and it
4379          * isn't clear that we would want to do so anyway; while we could apply
4380          * labeling without the support of the TUN user the resulting labeled
4381          * traffic from the other end of the connection would almost certainly
4382          * cause confusion to the TUN user that had no idea network labeling
4383          * protocols were being used */
4384
4385         /* see the comments in selinux_tun_dev_create() about why we don't use
4386          * the sockcreate SID here */
4387
4388         sksec->sid = current_sid();
4389         sksec->sclass = SECCLASS_TUN_SOCKET;
4390 }
4391
4392 static int selinux_tun_dev_attach(struct sock *sk)
4393 {
4394         struct sk_security_struct *sksec = sk->sk_security;
4395         u32 sid = current_sid();
4396         int err;
4397
4398         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4399                            TUN_SOCKET__RELABELFROM, NULL);
4400         if (err)
4401                 return err;
4402         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4403                            TUN_SOCKET__RELABELTO, NULL);
4404         if (err)
4405                 return err;
4406
4407         sksec->sid = sid;
4408
4409         return 0;
4410 }
4411
4412 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4413 {
4414         int err = 0;
4415         u32 perm;
4416         struct nlmsghdr *nlh;
4417         struct sk_security_struct *sksec = sk->sk_security;
4418
4419         if (skb->len < NLMSG_SPACE(0)) {
4420                 err = -EINVAL;
4421                 goto out;
4422         }
4423         nlh = nlmsg_hdr(skb);
4424
4425         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4426         if (err) {
4427                 if (err == -EINVAL) {
4428                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4429                                   "SELinux:  unrecognized netlink message"
4430                                   " type=%hu for sclass=%hu\n",
4431                                   nlh->nlmsg_type, sksec->sclass);
4432                         if (!selinux_enforcing || security_get_allow_unknown())
4433                                 err = 0;
4434                 }
4435
4436                 /* Ignore */
4437                 if (err == -ENOENT)
4438                         err = 0;
4439                 goto out;
4440         }
4441
4442         err = sock_has_perm(current, sk, perm);
4443 out:
4444         return err;
4445 }
4446
4447 #ifdef CONFIG_NETFILTER
4448
4449 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4450                                        u16 family)
4451 {
4452         int err;
4453         char *addrp;
4454         u32 peer_sid;
4455         struct common_audit_data ad;
4456         u8 secmark_active;
4457         u8 netlbl_active;
4458         u8 peerlbl_active;
4459
4460         if (!selinux_policycap_netpeer)
4461                 return NF_ACCEPT;
4462
4463         secmark_active = selinux_secmark_enabled();
4464         netlbl_active = netlbl_enabled();
4465         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4466         if (!secmark_active && !peerlbl_active)
4467                 return NF_ACCEPT;
4468
4469         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4470                 return NF_DROP;
4471
4472         COMMON_AUDIT_DATA_INIT(&ad, NET);
4473         ad.u.net.netif = ifindex;
4474         ad.u.net.family = family;
4475         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4476                 return NF_DROP;
4477
4478         if (peerlbl_active) {
4479                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4480                                                peer_sid, &ad);
4481                 if (err) {
4482                         selinux_netlbl_err(skb, err, 1);
4483                         return NF_DROP;
4484                 }
4485         }
4486
4487         if (secmark_active)
4488                 if (avc_has_perm(peer_sid, skb->secmark,
4489                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4490                         return NF_DROP;
4491
4492         if (netlbl_active)
4493                 /* we do this in the FORWARD path and not the POST_ROUTING
4494                  * path because we want to make sure we apply the necessary
4495                  * labeling before IPsec is applied so we can leverage AH
4496                  * protection */
4497                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4498                         return NF_DROP;
4499
4500         return NF_ACCEPT;
4501 }
4502
4503 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4504                                          struct sk_buff *skb,
4505                                          const struct net_device *in,
4506                                          const struct net_device *out,
4507                                          int (*okfn)(struct sk_buff *))
4508 {
4509         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4510 }
4511
4512 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4513 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4514                                          struct sk_buff *skb,
4515                                          const struct net_device *in,
4516                                          const struct net_device *out,
4517                                          int (*okfn)(struct sk_buff *))
4518 {
4519         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4520 }
4521 #endif  /* IPV6 */
4522
4523 static unsigned int selinux_ip_output(struct sk_buff *skb,
4524                                       u16 family)
4525 {
4526         u32 sid;
4527
4528         if (!netlbl_enabled())
4529                 return NF_ACCEPT;
4530
4531         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4532          * because we want to make sure we apply the necessary labeling
4533          * before IPsec is applied so we can leverage AH protection */
4534         if (skb->sk) {
4535                 struct sk_security_struct *sksec = skb->sk->sk_security;
4536                 sid = sksec->sid;
4537         } else
4538                 sid = SECINITSID_KERNEL;
4539         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4540                 return NF_DROP;
4541
4542         return NF_ACCEPT;
4543 }
4544
4545 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4546                                         struct sk_buff *skb,
4547                                         const struct net_device *in,
4548                                         const struct net_device *out,
4549                                         int (*okfn)(struct sk_buff *))
4550 {
4551         return selinux_ip_output(skb, PF_INET);
4552 }
4553
4554 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4555                                                 int ifindex,
4556                                                 u16 family)
4557 {
4558         struct sock *sk = skb->sk;
4559         struct sk_security_struct *sksec;
4560         struct common_audit_data ad;
4561         char *addrp;
4562         u8 proto;
4563
4564         if (sk == NULL)
4565                 return NF_ACCEPT;
4566         sksec = sk->sk_security;
4567
4568         COMMON_AUDIT_DATA_INIT(&ad, NET);
4569         ad.u.net.netif = ifindex;
4570         ad.u.net.family = family;
4571         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4572                 return NF_DROP;
4573
4574         if (selinux_secmark_enabled())
4575                 if (avc_has_perm(sksec->sid, skb->secmark,
4576                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4577                         return NF_DROP_ERR(-ECONNREFUSED);
4578
4579         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4580                 return NF_DROP_ERR(-ECONNREFUSED);
4581
4582         return NF_ACCEPT;
4583 }
4584
4585 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4586                                          u16 family)
4587 {
4588         u32 secmark_perm;
4589         u32 peer_sid;
4590         struct sock *sk;
4591         struct common_audit_data ad;
4592         char *addrp;
4593         u8 secmark_active;
4594         u8 peerlbl_active;
4595
4596         /* If any sort of compatibility mode is enabled then handoff processing
4597          * to the selinux_ip_postroute_compat() function to deal with the
4598          * special handling.  We do this in an attempt to keep this function
4599          * as fast and as clean as possible. */
4600         if (!selinux_policycap_netpeer)
4601                 return selinux_ip_postroute_compat(skb, ifindex, family);
4602 #ifdef CONFIG_XFRM
4603         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4604          * packet transformation so allow the packet to pass without any checks
4605          * since we'll have another chance to perform access control checks
4606          * when the packet is on it's final way out.
4607          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4608          *       is NULL, in this case go ahead and apply access control. */
4609         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4610                 return NF_ACCEPT;
4611 #endif
4612         secmark_active = selinux_secmark_enabled();
4613         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4614         if (!secmark_active && !peerlbl_active)
4615                 return NF_ACCEPT;
4616
4617         /* if the packet is being forwarded then get the peer label from the
4618          * packet itself; otherwise check to see if it is from a local
4619          * application or the kernel, if from an application get the peer label
4620          * from the sending socket, otherwise use the kernel's sid */
4621         sk = skb->sk;
4622         if (sk == NULL) {
4623                 if (skb->skb_iif) {
4624                         secmark_perm = PACKET__FORWARD_OUT;
4625                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4626                                 return NF_DROP;
4627                 } else {
4628                         secmark_perm = PACKET__SEND;
4629                         peer_sid = SECINITSID_KERNEL;
4630                 }
4631         } else {
4632                 struct sk_security_struct *sksec = sk->sk_security;
4633                 peer_sid = sksec->sid;
4634                 secmark_perm = PACKET__SEND;
4635         }
4636
4637         COMMON_AUDIT_DATA_INIT(&ad, NET);
4638         ad.u.net.netif = ifindex;
4639         ad.u.net.family = family;
4640         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4641                 return NF_DROP;
4642
4643         if (secmark_active)
4644                 if (avc_has_perm(peer_sid, skb->secmark,
4645                                  SECCLASS_PACKET, secmark_perm, &ad))
4646                         return NF_DROP_ERR(-ECONNREFUSED);
4647
4648         if (peerlbl_active) {
4649                 u32 if_sid;
4650                 u32 node_sid;
4651
4652                 if (sel_netif_sid(ifindex, &if_sid))
4653                         return NF_DROP;
4654                 if (avc_has_perm(peer_sid, if_sid,
4655                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4656                         return NF_DROP_ERR(-ECONNREFUSED);
4657
4658                 if (sel_netnode_sid(addrp, family, &node_sid))
4659                         return NF_DROP;
4660                 if (avc_has_perm(peer_sid, node_sid,
4661                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4662                         return NF_DROP_ERR(-ECONNREFUSED);
4663         }
4664
4665         return NF_ACCEPT;
4666 }
4667
4668 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4669                                            struct sk_buff *skb,
4670                                            const struct net_device *in,
4671                                            const struct net_device *out,
4672                                            int (*okfn)(struct sk_buff *))
4673 {
4674         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4675 }
4676
4677 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4678 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4679                                            struct sk_buff *skb,
4680                                            const struct net_device *in,
4681                                            const struct net_device *out,
4682                                            int (*okfn)(struct sk_buff *))
4683 {
4684         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4685 }
4686 #endif  /* IPV6 */
4687
4688 #endif  /* CONFIG_NETFILTER */
4689
4690 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4691 {
4692         int err;
4693
4694         err = cap_netlink_send(sk, skb);
4695         if (err)
4696                 return err;
4697
4698         return selinux_nlmsg_perm(sk, skb);
4699 }
4700
4701 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4702 {
4703         int err;
4704         struct common_audit_data ad;
4705
4706         err = cap_netlink_recv(skb, capability);
4707         if (err)
4708                 return err;
4709
4710         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4711         ad.u.cap = capability;
4712
4713         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4714                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4715 }
4716
4717 static int ipc_alloc_security(struct task_struct *task,
4718                               struct kern_ipc_perm *perm,
4719                               u16 sclass)
4720 {
4721         struct ipc_security_struct *isec;
4722         u32 sid;
4723
4724         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4725         if (!isec)
4726                 return -ENOMEM;
4727
4728         sid = task_sid(task);
4729         isec->sclass = sclass;
4730         isec->sid = sid;
4731         perm->security = isec;
4732
4733         return 0;
4734 }
4735
4736 static void ipc_free_security(struct kern_ipc_perm *perm)
4737 {
4738         struct ipc_security_struct *isec = perm->security;
4739         perm->security = NULL;
4740         kfree(isec);
4741 }
4742
4743 static int msg_msg_alloc_security(struct msg_msg *msg)
4744 {
4745         struct msg_security_struct *msec;
4746
4747         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4748         if (!msec)
4749                 return -ENOMEM;
4750
4751         msec->sid = SECINITSID_UNLABELED;
4752         msg->security = msec;
4753
4754         return 0;
4755 }
4756
4757 static void msg_msg_free_security(struct msg_msg *msg)
4758 {
4759         struct msg_security_struct *msec = msg->security;
4760
4761         msg->security = NULL;
4762         kfree(msec);
4763 }
4764
4765 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4766                         u32 perms)
4767 {
4768         struct ipc_security_struct *isec;
4769         struct common_audit_data ad;
4770         u32 sid = current_sid();
4771
4772         isec = ipc_perms->security;
4773
4774         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4775         ad.u.ipc_id = ipc_perms->key;
4776
4777         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4778 }
4779
4780 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4781 {
4782         return msg_msg_alloc_security(msg);
4783 }
4784
4785 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4786 {
4787         msg_msg_free_security(msg);
4788 }
4789
4790 /* message queue security operations */
4791 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4792 {
4793         struct ipc_security_struct *isec;
4794         struct common_audit_data ad;
4795         u32 sid = current_sid();
4796         int rc;
4797
4798         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4799         if (rc)
4800                 return rc;
4801
4802         isec = msq->q_perm.security;
4803
4804         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4805         ad.u.ipc_id = msq->q_perm.key;
4806
4807         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4808                           MSGQ__CREATE, &ad);
4809         if (rc) {
4810                 ipc_free_security(&msq->q_perm);
4811                 return rc;
4812         }
4813         return 0;
4814 }
4815
4816 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4817 {
4818         ipc_free_security(&msq->q_perm);
4819 }
4820
4821 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4822 {
4823         struct ipc_security_struct *isec;
4824         struct common_audit_data ad;
4825         u32 sid = current_sid();
4826
4827         isec = msq->q_perm.security;
4828
4829         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4830         ad.u.ipc_id = msq->q_perm.key;
4831
4832         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4833                             MSGQ__ASSOCIATE, &ad);
4834 }
4835
4836 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4837 {
4838         int err;
4839         int perms;
4840
4841         switch (cmd) {
4842         case IPC_INFO:
4843         case MSG_INFO:
4844                 /* No specific object, just general system-wide information. */
4845                 return task_has_system(current, SYSTEM__IPC_INFO);
4846         case IPC_STAT:
4847         case MSG_STAT:
4848                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4849                 break;
4850         case IPC_SET:
4851                 perms = MSGQ__SETATTR;
4852                 break;
4853         case IPC_RMID:
4854                 perms = MSGQ__DESTROY;
4855                 break;
4856         default:
4857                 return 0;
4858         }
4859
4860         err = ipc_has_perm(&msq->q_perm, perms);
4861         return err;
4862 }
4863
4864 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4865 {
4866         struct ipc_security_struct *isec;
4867         struct msg_security_struct *msec;
4868         struct common_audit_data ad;
4869         u32 sid = current_sid();
4870         int rc;
4871
4872         isec = msq->q_perm.security;
4873         msec = msg->security;
4874
4875         /*
4876          * First time through, need to assign label to the message
4877          */
4878         if (msec->sid == SECINITSID_UNLABELED) {
4879                 /*
4880                  * Compute new sid based on current process and
4881                  * message queue this message will be stored in
4882                  */
4883                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4884                                              NULL, &msec->sid);
4885                 if (rc)
4886                         return rc;
4887         }
4888
4889         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4890         ad.u.ipc_id = msq->q_perm.key;
4891
4892         /* Can this process write to the queue? */
4893         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4894                           MSGQ__WRITE, &ad);
4895         if (!rc)
4896                 /* Can this process send the message */
4897                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4898                                   MSG__SEND, &ad);
4899         if (!rc)
4900                 /* Can the message be put in the queue? */
4901                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4902                                   MSGQ__ENQUEUE, &ad);
4903
4904         return rc;
4905 }
4906
4907 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4908                                     struct task_struct *target,
4909                                     long type, int mode)
4910 {
4911         struct ipc_security_struct *isec;
4912         struct msg_security_struct *msec;
4913         struct common_audit_data ad;
4914         u32 sid = task_sid(target);
4915         int rc;
4916
4917         isec = msq->q_perm.security;
4918         msec = msg->security;
4919
4920         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4921         ad.u.ipc_id = msq->q_perm.key;
4922
4923         rc = avc_has_perm(sid, isec->sid,
4924                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4925         if (!rc)
4926                 rc = avc_has_perm(sid, msec->sid,
4927                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4928         return rc;
4929 }
4930
4931 /* Shared Memory security operations */
4932 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4933 {
4934         struct ipc_security_struct *isec;
4935         struct common_audit_data ad;
4936         u32 sid = current_sid();
4937         int rc;
4938
4939         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4940         if (rc)
4941                 return rc;
4942
4943         isec = shp->shm_perm.security;
4944
4945         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4946         ad.u.ipc_id = shp->shm_perm.key;
4947
4948         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4949                           SHM__CREATE, &ad);
4950         if (rc) {
4951                 ipc_free_security(&shp->shm_perm);
4952                 return rc;
4953         }
4954         return 0;
4955 }
4956
4957 static void selinux_shm_free_security(struct shmid_kernel *shp)
4958 {
4959         ipc_free_security(&shp->shm_perm);
4960 }
4961
4962 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4963 {
4964         struct ipc_security_struct *isec;
4965         struct common_audit_data ad;
4966         u32 sid = current_sid();
4967
4968         isec = shp->shm_perm.security;
4969
4970         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4971         ad.u.ipc_id = shp->shm_perm.key;
4972
4973         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4974                             SHM__ASSOCIATE, &ad);
4975 }
4976
4977 /* Note, at this point, shp is locked down */
4978 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4979 {
4980         int perms;
4981         int err;
4982
4983         switch (cmd) {
4984         case IPC_INFO:
4985         case SHM_INFO:
4986                 /* No specific object, just general system-wide information. */
4987                 return task_has_system(current, SYSTEM__IPC_INFO);
4988         case IPC_STAT:
4989         case SHM_STAT:
4990                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4991                 break;
4992         case IPC_SET:
4993                 perms = SHM__SETATTR;
4994                 break;
4995         case SHM_LOCK:
4996         case SHM_UNLOCK:
4997                 perms = SHM__LOCK;
4998                 break;
4999         case IPC_RMID:
5000                 perms = SHM__DESTROY;
5001                 break;
5002         default:
5003                 return 0;
5004         }
5005
5006         err = ipc_has_perm(&shp->shm_perm, perms);
5007         return err;
5008 }
5009
5010 static int selinux_shm_shmat(struct shmid_kernel *shp,
5011                              char __user *shmaddr, int shmflg)
5012 {
5013         u32 perms;
5014
5015         if (shmflg & SHM_RDONLY)
5016                 perms = SHM__READ;
5017         else
5018                 perms = SHM__READ | SHM__WRITE;
5019
5020         return ipc_has_perm(&shp->shm_perm, perms);
5021 }
5022
5023 /* Semaphore security operations */
5024 static int selinux_sem_alloc_security(struct sem_array *sma)
5025 {
5026         struct ipc_security_struct *isec;
5027         struct common_audit_data ad;
5028         u32 sid = current_sid();
5029         int rc;
5030
5031         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5032         if (rc)
5033                 return rc;
5034
5035         isec = sma->sem_perm.security;
5036
5037         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5038         ad.u.ipc_id = sma->sem_perm.key;
5039
5040         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5041                           SEM__CREATE, &ad);
5042         if (rc) {
5043                 ipc_free_security(&sma->sem_perm);
5044                 return rc;
5045         }
5046         return 0;
5047 }
5048
5049 static void selinux_sem_free_security(struct sem_array *sma)
5050 {
5051         ipc_free_security(&sma->sem_perm);
5052 }
5053
5054 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5055 {
5056         struct ipc_security_struct *isec;
5057         struct common_audit_data ad;
5058         u32 sid = current_sid();
5059
5060         isec = sma->sem_perm.security;
5061
5062         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5063         ad.u.ipc_id = sma->sem_perm.key;
5064
5065         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5066                             SEM__ASSOCIATE, &ad);
5067 }
5068
5069 /* Note, at this point, sma is locked down */
5070 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5071 {
5072         int err;
5073         u32 perms;
5074
5075         switch (cmd) {
5076         case IPC_INFO:
5077         case SEM_INFO:
5078                 /* No specific object, just general system-wide information. */
5079                 return task_has_system(current, SYSTEM__IPC_INFO);
5080         case GETPID:
5081         case GETNCNT:
5082         case GETZCNT:
5083                 perms = SEM__GETATTR;
5084                 break;
5085         case GETVAL:
5086         case GETALL:
5087                 perms = SEM__READ;
5088                 break;
5089         case SETVAL:
5090         case SETALL:
5091                 perms = SEM__WRITE;
5092                 break;
5093         case IPC_RMID:
5094                 perms = SEM__DESTROY;
5095                 break;
5096         case IPC_SET:
5097                 perms = SEM__SETATTR;
5098                 break;
5099         case IPC_STAT:
5100         case SEM_STAT:
5101                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5102                 break;
5103         default:
5104                 return 0;
5105         }
5106
5107         err = ipc_has_perm(&sma->sem_perm, perms);
5108         return err;
5109 }
5110
5111 static int selinux_sem_semop(struct sem_array *sma,
5112                              struct sembuf *sops, unsigned nsops, int alter)
5113 {
5114         u32 perms;
5115
5116         if (alter)
5117                 perms = SEM__READ | SEM__WRITE;
5118         else
5119                 perms = SEM__READ;
5120
5121         return ipc_has_perm(&sma->sem_perm, perms);
5122 }
5123
5124 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5125 {
5126         u32 av = 0;
5127
5128         av = 0;
5129         if (flag & S_IRUGO)
5130                 av |= IPC__UNIX_READ;
5131         if (flag & S_IWUGO)
5132                 av |= IPC__UNIX_WRITE;
5133
5134         if (av == 0)
5135                 return 0;
5136
5137         return ipc_has_perm(ipcp, av);
5138 }
5139
5140 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5141 {
5142         struct ipc_security_struct *isec = ipcp->security;
5143         *secid = isec->sid;
5144 }
5145
5146 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5147 {
5148         if (inode)
5149                 inode_doinit_with_dentry(inode, dentry);
5150 }
5151
5152 static int selinux_getprocattr(struct task_struct *p,
5153                                char *name, char **value)
5154 {
5155         const struct task_security_struct *__tsec;
5156         u32 sid;
5157         int error;
5158         unsigned len;
5159
5160         if (current != p) {
5161                 error = current_has_perm(p, PROCESS__GETATTR);
5162                 if (error)
5163                         return error;
5164         }
5165
5166         rcu_read_lock();
5167         __tsec = __task_cred(p)->security;
5168
5169         if (!strcmp(name, "current"))
5170                 sid = __tsec->sid;
5171         else if (!strcmp(name, "prev"))
5172                 sid = __tsec->osid;
5173         else if (!strcmp(name, "exec"))
5174                 sid = __tsec->exec_sid;
5175         else if (!strcmp(name, "fscreate"))
5176                 sid = __tsec->create_sid;
5177         else if (!strcmp(name, "keycreate"))
5178                 sid = __tsec->keycreate_sid;
5179         else if (!strcmp(name, "sockcreate"))
5180                 sid = __tsec->sockcreate_sid;
5181         else
5182                 goto invalid;
5183         rcu_read_unlock();
5184
5185         if (!sid)
5186                 return 0;
5187
5188         error = security_sid_to_context(sid, value, &len);
5189         if (error)
5190                 return error;
5191         return len;
5192
5193 invalid:
5194         rcu_read_unlock();
5195         return -EINVAL;
5196 }
5197
5198 static int selinux_setprocattr(struct task_struct *p,
5199                                char *name, void *value, size_t size)
5200 {
5201         struct task_security_struct *tsec;
5202         struct task_struct *tracer;
5203         struct cred *new;
5204         u32 sid = 0, ptsid;
5205         int error;
5206         char *str = value;
5207
5208         if (current != p) {
5209                 /* SELinux only allows a process to change its own
5210                    security attributes. */
5211                 return -EACCES;
5212         }
5213
5214         /*
5215          * Basic control over ability to set these attributes at all.
5216          * current == p, but we'll pass them separately in case the
5217          * above restriction is ever removed.
5218          */
5219         if (!strcmp(name, "exec"))
5220                 error = current_has_perm(p, PROCESS__SETEXEC);
5221         else if (!strcmp(name, "fscreate"))
5222                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5223         else if (!strcmp(name, "keycreate"))
5224                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5225         else if (!strcmp(name, "sockcreate"))
5226                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5227         else if (!strcmp(name, "current"))
5228                 error = current_has_perm(p, PROCESS__SETCURRENT);
5229         else
5230                 error = -EINVAL;
5231         if (error)
5232                 return error;
5233
5234         /* Obtain a SID for the context, if one was specified. */
5235         if (size && str[1] && str[1] != '\n') {
5236                 if (str[size-1] == '\n') {
5237                         str[size-1] = 0;
5238                         size--;
5239                 }
5240                 error = security_context_to_sid(value, size, &sid);
5241                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5242                         if (!capable(CAP_MAC_ADMIN))
5243                                 return error;
5244                         error = security_context_to_sid_force(value, size,
5245                                                               &sid);
5246                 }
5247                 if (error)
5248                         return error;
5249         }
5250
5251         new = prepare_creds();
5252         if (!new)
5253                 return -ENOMEM;
5254
5255         /* Permission checking based on the specified context is
5256            performed during the actual operation (execve,
5257            open/mkdir/...), when we know the full context of the
5258            operation.  See selinux_bprm_set_creds for the execve
5259            checks and may_create for the file creation checks. The
5260            operation will then fail if the context is not permitted. */
5261         tsec = new->security;
5262         if (!strcmp(name, "exec")) {
5263                 tsec->exec_sid = sid;
5264         } else if (!strcmp(name, "fscreate")) {
5265                 tsec->create_sid = sid;
5266         } else if (!strcmp(name, "keycreate")) {
5267                 error = may_create_key(sid, p);
5268                 if (error)
5269                         goto abort_change;
5270                 tsec->keycreate_sid = sid;
5271         } else if (!strcmp(name, "sockcreate")) {
5272                 tsec->sockcreate_sid = sid;
5273         } else if (!strcmp(name, "current")) {
5274                 error = -EINVAL;
5275                 if (sid == 0)
5276                         goto abort_change;
5277
5278                 /* Only allow single threaded processes to change context */
5279                 error = -EPERM;
5280                 if (!current_is_single_threaded()) {
5281                         error = security_bounded_transition(tsec->sid, sid);
5282                         if (error)
5283                                 goto abort_change;
5284                 }
5285
5286                 /* Check permissions for the transition. */
5287                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5288                                      PROCESS__DYNTRANSITION, NULL);
5289                 if (error)
5290                         goto abort_change;
5291
5292                 /* Check for ptracing, and update the task SID if ok.
5293                    Otherwise, leave SID unchanged and fail. */
5294                 ptsid = 0;
5295                 task_lock(p);
5296                 tracer = tracehook_tracer_task(p);
5297                 if (tracer)
5298                         ptsid = task_sid(tracer);
5299                 task_unlock(p);
5300
5301                 if (tracer) {
5302                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5303                                              PROCESS__PTRACE, NULL);
5304                         if (error)
5305                                 goto abort_change;
5306                 }
5307
5308                 tsec->sid = sid;
5309         } else {
5310                 error = -EINVAL;
5311                 goto abort_change;
5312         }
5313
5314         commit_creds(new);
5315         return size;
5316
5317 abort_change:
5318         abort_creds(new);
5319         return error;
5320 }
5321
5322 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5323 {
5324         return security_sid_to_context(secid, secdata, seclen);
5325 }
5326
5327 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5328 {
5329         return security_context_to_sid(secdata, seclen, secid);
5330 }
5331
5332 static void selinux_release_secctx(char *secdata, u32 seclen)
5333 {
5334         kfree(secdata);
5335 }
5336
5337 /*
5338  *      called with inode->i_mutex locked
5339  */
5340 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5341 {
5342         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5343 }
5344
5345 /*
5346  *      called with inode->i_mutex locked
5347  */
5348 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5349 {
5350         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5351 }
5352
5353 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5354 {
5355         int len = 0;
5356         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5357                                                 ctx, true);
5358         if (len < 0)
5359                 return len;
5360         *ctxlen = len;
5361         return 0;
5362 }
5363 #ifdef CONFIG_KEYS
5364
5365 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5366                              unsigned long flags)
5367 {
5368         const struct task_security_struct *tsec;
5369         struct key_security_struct *ksec;
5370
5371         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5372         if (!ksec)
5373                 return -ENOMEM;
5374
5375         tsec = cred->security;
5376         if (tsec->keycreate_sid)
5377                 ksec->sid = tsec->keycreate_sid;
5378         else
5379                 ksec->sid = tsec->sid;
5380
5381         k->security = ksec;
5382         return 0;
5383 }
5384
5385 static void selinux_key_free(struct key *k)
5386 {
5387         struct key_security_struct *ksec = k->security;
5388
5389         k->security = NULL;
5390         kfree(ksec);
5391 }
5392
5393 static int selinux_key_permission(key_ref_t key_ref,
5394                                   const struct cred *cred,
5395                                   key_perm_t perm)
5396 {
5397         struct key *key;
5398         struct key_security_struct *ksec;
5399         u32 sid;
5400
5401         /* if no specific permissions are requested, we skip the
5402            permission check. No serious, additional covert channels
5403            appear to be created. */
5404         if (perm == 0)
5405                 return 0;
5406
5407         sid = cred_sid(cred);
5408
5409         key = key_ref_to_ptr(key_ref);
5410         ksec = key->security;
5411
5412         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5413 }
5414
5415 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5416 {
5417         struct key_security_struct *ksec = key->security;
5418         char *context = NULL;
5419         unsigned len;
5420         int rc;
5421
5422         rc = security_sid_to_context(ksec->sid, &context, &len);
5423         if (!rc)
5424                 rc = len;
5425         *_buffer = context;
5426         return rc;
5427 }
5428
5429 #endif
5430
5431 static struct security_operations selinux_ops = {
5432         .name =                         "selinux",
5433
5434         .ptrace_access_check =          selinux_ptrace_access_check,
5435         .ptrace_traceme =               selinux_ptrace_traceme,
5436         .capget =                       selinux_capget,
5437         .capset =                       selinux_capset,
5438         .capable =                      selinux_capable,
5439         .quotactl =                     selinux_quotactl,
5440         .quota_on =                     selinux_quota_on,
5441         .syslog =                       selinux_syslog,
5442         .vm_enough_memory =             selinux_vm_enough_memory,
5443
5444         .netlink_send =                 selinux_netlink_send,
5445         .netlink_recv =                 selinux_netlink_recv,
5446
5447         .bprm_set_creds =               selinux_bprm_set_creds,
5448         .bprm_committing_creds =        selinux_bprm_committing_creds,
5449         .bprm_committed_creds =         selinux_bprm_committed_creds,
5450         .bprm_secureexec =              selinux_bprm_secureexec,
5451
5452         .sb_alloc_security =            selinux_sb_alloc_security,
5453         .sb_free_security =             selinux_sb_free_security,
5454         .sb_copy_data =                 selinux_sb_copy_data,
5455         .sb_remount =                   selinux_sb_remount,
5456         .sb_kern_mount =                selinux_sb_kern_mount,
5457         .sb_show_options =              selinux_sb_show_options,
5458         .sb_statfs =                    selinux_sb_statfs,
5459         .sb_mount =                     selinux_mount,
5460         .sb_umount =                    selinux_umount,
5461         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5462         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5463         .sb_parse_opts_str =            selinux_parse_opts_str,
5464
5465
5466         .inode_alloc_security =         selinux_inode_alloc_security,
5467         .inode_free_security =          selinux_inode_free_security,
5468         .inode_init_security =          selinux_inode_init_security,
5469         .inode_create =                 selinux_inode_create,
5470         .inode_link =                   selinux_inode_link,
5471         .inode_unlink =                 selinux_inode_unlink,
5472         .inode_symlink =                selinux_inode_symlink,
5473         .inode_mkdir =                  selinux_inode_mkdir,
5474         .inode_rmdir =                  selinux_inode_rmdir,
5475         .inode_mknod =                  selinux_inode_mknod,
5476         .inode_rename =                 selinux_inode_rename,
5477         .inode_readlink =               selinux_inode_readlink,
5478         .inode_follow_link =            selinux_inode_follow_link,
5479         .inode_permission =             selinux_inode_permission,
5480         .inode_setattr =                selinux_inode_setattr,
5481         .inode_getattr =                selinux_inode_getattr,
5482         .inode_setxattr =               selinux_inode_setxattr,
5483         .inode_post_setxattr =          selinux_inode_post_setxattr,
5484         .inode_getxattr =               selinux_inode_getxattr,
5485         .inode_listxattr =              selinux_inode_listxattr,
5486         .inode_removexattr =            selinux_inode_removexattr,
5487         .inode_getsecurity =            selinux_inode_getsecurity,
5488         .inode_setsecurity =            selinux_inode_setsecurity,
5489         .inode_listsecurity =           selinux_inode_listsecurity,
5490         .inode_getsecid =               selinux_inode_getsecid,
5491
5492         .file_permission =              selinux_file_permission,
5493         .file_alloc_security =          selinux_file_alloc_security,
5494         .file_free_security =           selinux_file_free_security,
5495         .file_ioctl =                   selinux_file_ioctl,
5496         .file_mmap =                    selinux_file_mmap,
5497         .file_mprotect =                selinux_file_mprotect,
5498         .file_lock =                    selinux_file_lock,
5499         .file_fcntl =                   selinux_file_fcntl,
5500         .file_set_fowner =              selinux_file_set_fowner,
5501         .file_send_sigiotask =          selinux_file_send_sigiotask,
5502         .file_receive =                 selinux_file_receive,
5503
5504         .dentry_open =                  selinux_dentry_open,
5505
5506         .task_create =                  selinux_task_create,
5507         .cred_alloc_blank =             selinux_cred_alloc_blank,
5508         .cred_free =                    selinux_cred_free,
5509         .cred_prepare =                 selinux_cred_prepare,
5510         .cred_transfer =                selinux_cred_transfer,
5511         .kernel_act_as =                selinux_kernel_act_as,
5512         .kernel_create_files_as =       selinux_kernel_create_files_as,
5513         .kernel_module_request =        selinux_kernel_module_request,
5514         .task_setpgid =                 selinux_task_setpgid,
5515         .task_getpgid =                 selinux_task_getpgid,
5516         .task_getsid =                  selinux_task_getsid,
5517         .task_getsecid =                selinux_task_getsecid,
5518         .task_setnice =                 selinux_task_setnice,
5519         .task_setioprio =               selinux_task_setioprio,
5520         .task_getioprio =               selinux_task_getioprio,
5521         .task_setrlimit =               selinux_task_setrlimit,
5522         .task_setscheduler =            selinux_task_setscheduler,
5523         .task_getscheduler =            selinux_task_getscheduler,
5524         .task_movememory =              selinux_task_movememory,
5525         .task_kill =                    selinux_task_kill,
5526         .task_wait =                    selinux_task_wait,
5527         .task_to_inode =                selinux_task_to_inode,
5528
5529         .ipc_permission =               selinux_ipc_permission,
5530         .ipc_getsecid =                 selinux_ipc_getsecid,
5531
5532         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5533         .msg_msg_free_security =        selinux_msg_msg_free_security,
5534
5535         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5536         .msg_queue_free_security =      selinux_msg_queue_free_security,
5537         .msg_queue_associate =          selinux_msg_queue_associate,
5538         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5539         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5540         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5541
5542         .shm_alloc_security =           selinux_shm_alloc_security,
5543         .shm_free_security =            selinux_shm_free_security,
5544         .shm_associate =                selinux_shm_associate,
5545         .shm_shmctl =                   selinux_shm_shmctl,
5546         .shm_shmat =                    selinux_shm_shmat,
5547
5548         .sem_alloc_security =           selinux_sem_alloc_security,
5549         .sem_free_security =            selinux_sem_free_security,
5550         .sem_associate =                selinux_sem_associate,
5551         .sem_semctl =                   selinux_sem_semctl,
5552         .sem_semop =                    selinux_sem_semop,
5553
5554         .d_instantiate =                selinux_d_instantiate,
5555
5556         .getprocattr =                  selinux_getprocattr,
5557         .setprocattr =                  selinux_setprocattr,
5558
5559         .secid_to_secctx =              selinux_secid_to_secctx,
5560         .secctx_to_secid =              selinux_secctx_to_secid,
5561         .release_secctx =               selinux_release_secctx,
5562         .inode_notifysecctx =           selinux_inode_notifysecctx,
5563         .inode_setsecctx =              selinux_inode_setsecctx,
5564         .inode_getsecctx =              selinux_inode_getsecctx,
5565
5566         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5567         .unix_may_send =                selinux_socket_unix_may_send,
5568
5569         .socket_create =                selinux_socket_create,
5570         .socket_post_create =           selinux_socket_post_create,
5571         .socket_bind =                  selinux_socket_bind,
5572         .socket_connect =               selinux_socket_connect,
5573         .socket_listen =                selinux_socket_listen,
5574         .socket_accept =                selinux_socket_accept,
5575         .socket_sendmsg =               selinux_socket_sendmsg,
5576         .socket_recvmsg =               selinux_socket_recvmsg,
5577         .socket_getsockname =           selinux_socket_getsockname,
5578         .socket_getpeername =           selinux_socket_getpeername,
5579         .socket_getsockopt =            selinux_socket_getsockopt,
5580         .socket_setsockopt =            selinux_socket_setsockopt,
5581         .socket_shutdown =              selinux_socket_shutdown,
5582         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5583         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5584         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5585         .sk_alloc_security =            selinux_sk_alloc_security,
5586         .sk_free_security =             selinux_sk_free_security,
5587         .sk_clone_security =            selinux_sk_clone_security,
5588         .sk_getsecid =                  selinux_sk_getsecid,
5589         .sock_graft =                   selinux_sock_graft,
5590         .inet_conn_request =            selinux_inet_conn_request,
5591         .inet_csk_clone =               selinux_inet_csk_clone,
5592         .inet_conn_established =        selinux_inet_conn_established,
5593         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5594         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5595         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5596         .req_classify_flow =            selinux_req_classify_flow,
5597         .tun_dev_create =               selinux_tun_dev_create,
5598         .tun_dev_post_create =          selinux_tun_dev_post_create,
5599         .tun_dev_attach =               selinux_tun_dev_attach,
5600
5601 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5602         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5603         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5604         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5605         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5606         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5607         .xfrm_state_free_security =     selinux_xfrm_state_free,
5608         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5609         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5610         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5611         .xfrm_decode_session =          selinux_xfrm_decode_session,
5612 #endif
5613
5614 #ifdef CONFIG_KEYS
5615         .key_alloc =                    selinux_key_alloc,
5616         .key_free =                     selinux_key_free,
5617         .key_permission =               selinux_key_permission,
5618         .key_getsecurity =              selinux_key_getsecurity,
5619 #endif
5620
5621 #ifdef CONFIG_AUDIT
5622         .audit_rule_init =              selinux_audit_rule_init,
5623         .audit_rule_known =             selinux_audit_rule_known,
5624         .audit_rule_match =             selinux_audit_rule_match,
5625         .audit_rule_free =              selinux_audit_rule_free,
5626 #endif
5627 };
5628
5629 static __init int selinux_init(void)
5630 {
5631         if (!security_module_enable(&selinux_ops)) {
5632                 selinux_enabled = 0;
5633                 return 0;
5634         }
5635
5636         if (!selinux_enabled) {
5637                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5638                 return 0;
5639         }
5640
5641         printk(KERN_INFO "SELinux:  Initializing.\n");
5642
5643         /* Set the security state for the initial task. */
5644         cred_init_security();
5645
5646         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5647
5648         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5649                                             sizeof(struct inode_security_struct),
5650                                             0, SLAB_PANIC, NULL);
5651         avc_init();
5652
5653         if (register_security(&selinux_ops))
5654                 panic("SELinux: Unable to register with kernel.\n");
5655
5656         if (selinux_enforcing)
5657                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5658         else
5659                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5660
5661         return 0;
5662 }
5663
5664 static void delayed_superblock_init(struct super_block *sb, void *unused)
5665 {
5666         superblock_doinit(sb, NULL);
5667 }
5668
5669 void selinux_complete_init(void)
5670 {
5671         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5672
5673         /* Set up any superblocks initialized prior to the policy load. */
5674         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5675         iterate_supers(delayed_superblock_init, NULL);
5676 }
5677
5678 /* SELinux requires early initialization in order to label
5679    all processes and objects when they are created. */
5680 security_initcall(selinux_init);
5681
5682 #if defined(CONFIG_NETFILTER)
5683
5684 static struct nf_hook_ops selinux_ipv4_ops[] = {
5685         {
5686                 .hook =         selinux_ipv4_postroute,
5687                 .owner =        THIS_MODULE,
5688                 .pf =           PF_INET,
5689                 .hooknum =      NF_INET_POST_ROUTING,
5690                 .priority =     NF_IP_PRI_SELINUX_LAST,
5691         },
5692         {
5693                 .hook =         selinux_ipv4_forward,
5694                 .owner =        THIS_MODULE,
5695                 .pf =           PF_INET,
5696                 .hooknum =      NF_INET_FORWARD,
5697                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5698         },
5699         {
5700                 .hook =         selinux_ipv4_output,
5701                 .owner =        THIS_MODULE,
5702                 .pf =           PF_INET,
5703                 .hooknum =      NF_INET_LOCAL_OUT,
5704                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5705         }
5706 };
5707
5708 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5709
5710 static struct nf_hook_ops selinux_ipv6_ops[] = {
5711         {
5712                 .hook =         selinux_ipv6_postroute,
5713                 .owner =        THIS_MODULE,
5714                 .pf =           PF_INET6,
5715                 .hooknum =      NF_INET_POST_ROUTING,
5716                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5717         },
5718         {
5719                 .hook =         selinux_ipv6_forward,
5720                 .owner =        THIS_MODULE,
5721                 .pf =           PF_INET6,
5722                 .hooknum =      NF_INET_FORWARD,
5723                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5724         }
5725 };
5726
5727 #endif  /* IPV6 */
5728
5729 static int __init selinux_nf_ip_init(void)
5730 {
5731         int err = 0;
5732
5733         if (!selinux_enabled)
5734                 goto out;
5735
5736         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5737
5738         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5739         if (err)
5740                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5741
5742 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5743         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5744         if (err)
5745                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5746 #endif  /* IPV6 */
5747
5748 out:
5749         return err;
5750 }
5751
5752 __initcall(selinux_nf_ip_init);
5753
5754 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5755 static void selinux_nf_ip_exit(void)
5756 {
5757         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5758
5759         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5760 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5761         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5762 #endif  /* IPV6 */
5763 }
5764 #endif
5765
5766 #else /* CONFIG_NETFILTER */
5767
5768 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5769 #define selinux_nf_ip_exit()
5770 #endif
5771
5772 #endif /* CONFIG_NETFILTER */
5773
5774 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5775 static int selinux_disabled;
5776
5777 int selinux_disable(void)
5778 {
5779         extern void exit_sel_fs(void);
5780
5781         if (ss_initialized) {
5782                 /* Not permitted after initial policy load. */
5783                 return -EINVAL;
5784         }
5785
5786         if (selinux_disabled) {
5787                 /* Only do this once. */
5788                 return -EINVAL;
5789         }
5790
5791         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5792
5793         selinux_disabled = 1;
5794         selinux_enabled = 0;
5795
5796         reset_security_ops();
5797
5798         /* Try to destroy the avc node cache */
5799         avc_disable();
5800
5801         /* Unregister netfilter hooks. */
5802         selinux_nf_ip_exit();
5803
5804         /* Unregister selinuxfs. */
5805         exit_sel_fs();
5806
5807         return 0;
5808 }
5809 #endif