TOMOYO: Allow using owner/group etc. of file objects as conditions.
[linux-2.6.git] / security / selinux / hooks.c
1 /*
2  *  NSA Security-Enhanced Linux (SELinux) security module
3  *
4  *  This file contains the SELinux hook function implementations.
5  *
6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
7  *            Chris Vance, <cvance@nai.com>
8  *            Wayne Salamon, <wsalamon@nai.com>
9  *            James Morris <jmorris@redhat.com>
10  *
11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *                                         Eric Paris <eparis@redhat.com>
14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15  *                          <dgoeddel@trustedcs.com>
16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17  *      Paul Moore <paul.moore@hp.com>
18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
20  *
21  *      This program is free software; you can redistribute it and/or modify
22  *      it under the terms of the GNU General Public License version 2,
23  *      as published by the Free Software Foundation.
24  */
25
26 #include <linux/init.h>
27 #include <linux/kd.h>
28 #include <linux/kernel.h>
29 #include <linux/tracehook.h>
30 #include <linux/errno.h>
31 #include <linux/ext2_fs.h>
32 #include <linux/sched.h>
33 #include <linux/security.h>
34 #include <linux/xattr.h>
35 #include <linux/capability.h>
36 #include <linux/unistd.h>
37 #include <linux/mm.h>
38 #include <linux/mman.h>
39 #include <linux/slab.h>
40 #include <linux/pagemap.h>
41 #include <linux/proc_fs.h>
42 #include <linux/swap.h>
43 #include <linux/spinlock.h>
44 #include <linux/syscalls.h>
45 #include <linux/dcache.h>
46 #include <linux/file.h>
47 #include <linux/fdtable.h>
48 #include <linux/namei.h>
49 #include <linux/mount.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h>             /* for local_port_range[] */
55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
56 #include <net/net_namespace.h>
57 #include <net/netlabel.h>
58 #include <linux/uaccess.h>
59 #include <asm/ioctls.h>
60 #include <asm/atomic.h>
61 #include <linux/bitops.h>
62 #include <linux/interrupt.h>
63 #include <linux/netdevice.h>    /* for network interface checks */
64 #include <linux/netlink.h>
65 #include <linux/tcp.h>
66 #include <linux/udp.h>
67 #include <linux/dccp.h>
68 #include <linux/quota.h>
69 #include <linux/un.h>           /* for Unix socket types */
70 #include <net/af_unix.h>        /* for Unix socket types */
71 #include <linux/parser.h>
72 #include <linux/nfs_mount.h>
73 #include <net/ipv6.h>
74 #include <linux/hugetlb.h>
75 #include <linux/personality.h>
76 #include <linux/audit.h>
77 #include <linux/string.h>
78 #include <linux/selinux.h>
79 #include <linux/mutex.h>
80 #include <linux/posix-timers.h>
81 #include <linux/syslog.h>
82 #include <linux/user_namespace.h>
83
84 #include "avc.h"
85 #include "objsec.h"
86 #include "netif.h"
87 #include "netnode.h"
88 #include "netport.h"
89 #include "xfrm.h"
90 #include "netlabel.h"
91 #include "audit.h"
92
93 #define NUM_SEL_MNT_OPTS 5
94
95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96 extern struct security_operations *security_ops;
97
98 /* SECMARK reference count */
99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 int selinux_enforcing;
103
104 static int __init enforcing_setup(char *str)
105 {
106         unsigned long enforcing;
107         if (!strict_strtoul(str, 0, &enforcing))
108                 selinux_enforcing = enforcing ? 1 : 0;
109         return 1;
110 }
111 __setup("enforcing=", enforcing_setup);
112 #endif
113
114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117 static int __init selinux_enabled_setup(char *str)
118 {
119         unsigned long enabled;
120         if (!strict_strtoul(str, 0, &enabled))
121                 selinux_enabled = enabled ? 1 : 0;
122         return 1;
123 }
124 __setup("selinux=", selinux_enabled_setup);
125 #else
126 int selinux_enabled = 1;
127 #endif
128
129 static struct kmem_cache *sel_inode_cache;
130
131 /**
132  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133  *
134  * Description:
135  * This function checks the SECMARK reference counter to see if any SECMARK
136  * targets are currently configured, if the reference counter is greater than
137  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
138  * enabled, false (0) if SECMARK is disabled.
139  *
140  */
141 static int selinux_secmark_enabled(void)
142 {
143         return (atomic_read(&selinux_secmark_refcount) > 0);
144 }
145
146 /*
147  * initialise the security for the init task
148  */
149 static void cred_init_security(void)
150 {
151         struct cred *cred = (struct cred *) current->real_cred;
152         struct task_security_struct *tsec;
153
154         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
155         if (!tsec)
156                 panic("SELinux:  Failed to initialize initial task.\n");
157
158         tsec->osid = tsec->sid = SECINITSID_KERNEL;
159         cred->security = tsec;
160 }
161
162 /*
163  * get the security ID of a set of credentials
164  */
165 static inline u32 cred_sid(const struct cred *cred)
166 {
167         const struct task_security_struct *tsec;
168
169         tsec = cred->security;
170         return tsec->sid;
171 }
172
173 /*
174  * get the objective security ID of a task
175  */
176 static inline u32 task_sid(const struct task_struct *task)
177 {
178         u32 sid;
179
180         rcu_read_lock();
181         sid = cred_sid(__task_cred(task));
182         rcu_read_unlock();
183         return sid;
184 }
185
186 /*
187  * get the subjective security ID of the current task
188  */
189 static inline u32 current_sid(void)
190 {
191         const struct task_security_struct *tsec = current_security();
192
193         return tsec->sid;
194 }
195
196 /* Allocate and free functions for each kind of security blob. */
197
198 static int inode_alloc_security(struct inode *inode)
199 {
200         struct inode_security_struct *isec;
201         u32 sid = current_sid();
202
203         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
204         if (!isec)
205                 return -ENOMEM;
206
207         mutex_init(&isec->lock);
208         INIT_LIST_HEAD(&isec->list);
209         isec->inode = inode;
210         isec->sid = SECINITSID_UNLABELED;
211         isec->sclass = SECCLASS_FILE;
212         isec->task_sid = sid;
213         inode->i_security = isec;
214
215         return 0;
216 }
217
218 static void inode_free_security(struct inode *inode)
219 {
220         struct inode_security_struct *isec = inode->i_security;
221         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
222
223         spin_lock(&sbsec->isec_lock);
224         if (!list_empty(&isec->list))
225                 list_del_init(&isec->list);
226         spin_unlock(&sbsec->isec_lock);
227
228         inode->i_security = NULL;
229         kmem_cache_free(sel_inode_cache, isec);
230 }
231
232 static int file_alloc_security(struct file *file)
233 {
234         struct file_security_struct *fsec;
235         u32 sid = current_sid();
236
237         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
238         if (!fsec)
239                 return -ENOMEM;
240
241         fsec->sid = sid;
242         fsec->fown_sid = sid;
243         file->f_security = fsec;
244
245         return 0;
246 }
247
248 static void file_free_security(struct file *file)
249 {
250         struct file_security_struct *fsec = file->f_security;
251         file->f_security = NULL;
252         kfree(fsec);
253 }
254
255 static int superblock_alloc_security(struct super_block *sb)
256 {
257         struct superblock_security_struct *sbsec;
258
259         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
260         if (!sbsec)
261                 return -ENOMEM;
262
263         mutex_init(&sbsec->lock);
264         INIT_LIST_HEAD(&sbsec->isec_head);
265         spin_lock_init(&sbsec->isec_lock);
266         sbsec->sb = sb;
267         sbsec->sid = SECINITSID_UNLABELED;
268         sbsec->def_sid = SECINITSID_FILE;
269         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
270         sb->s_security = sbsec;
271
272         return 0;
273 }
274
275 static void superblock_free_security(struct super_block *sb)
276 {
277         struct superblock_security_struct *sbsec = sb->s_security;
278         sb->s_security = NULL;
279         kfree(sbsec);
280 }
281
282 /* The security server must be initialized before
283    any labeling or access decisions can be provided. */
284 extern int ss_initialized;
285
286 /* The file system's label must be initialized prior to use. */
287
288 static const char *labeling_behaviors[6] = {
289         "uses xattr",
290         "uses transition SIDs",
291         "uses task SIDs",
292         "uses genfs_contexts",
293         "not configured for labeling",
294         "uses mountpoint labeling",
295 };
296
297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
298
299 static inline int inode_doinit(struct inode *inode)
300 {
301         return inode_doinit_with_dentry(inode, NULL);
302 }
303
304 enum {
305         Opt_error = -1,
306         Opt_context = 1,
307         Opt_fscontext = 2,
308         Opt_defcontext = 3,
309         Opt_rootcontext = 4,
310         Opt_labelsupport = 5,
311 };
312
313 static const match_table_t tokens = {
314         {Opt_context, CONTEXT_STR "%s"},
315         {Opt_fscontext, FSCONTEXT_STR "%s"},
316         {Opt_defcontext, DEFCONTEXT_STR "%s"},
317         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
318         {Opt_labelsupport, LABELSUPP_STR},
319         {Opt_error, NULL},
320 };
321
322 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
323
324 static int may_context_mount_sb_relabel(u32 sid,
325                         struct superblock_security_struct *sbsec,
326                         const struct cred *cred)
327 {
328         const struct task_security_struct *tsec = cred->security;
329         int rc;
330
331         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
332                           FILESYSTEM__RELABELFROM, NULL);
333         if (rc)
334                 return rc;
335
336         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
337                           FILESYSTEM__RELABELTO, NULL);
338         return rc;
339 }
340
341 static int may_context_mount_inode_relabel(u32 sid,
342                         struct superblock_security_struct *sbsec,
343                         const struct cred *cred)
344 {
345         const struct task_security_struct *tsec = cred->security;
346         int rc;
347         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
348                           FILESYSTEM__RELABELFROM, NULL);
349         if (rc)
350                 return rc;
351
352         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
353                           FILESYSTEM__ASSOCIATE, NULL);
354         return rc;
355 }
356
357 static int sb_finish_set_opts(struct super_block *sb)
358 {
359         struct superblock_security_struct *sbsec = sb->s_security;
360         struct dentry *root = sb->s_root;
361         struct inode *root_inode = root->d_inode;
362         int rc = 0;
363
364         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
365                 /* Make sure that the xattr handler exists and that no
366                    error other than -ENODATA is returned by getxattr on
367                    the root directory.  -ENODATA is ok, as this may be
368                    the first boot of the SELinux kernel before we have
369                    assigned xattr values to the filesystem. */
370                 if (!root_inode->i_op->getxattr) {
371                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
372                                "xattr support\n", sb->s_id, sb->s_type->name);
373                         rc = -EOPNOTSUPP;
374                         goto out;
375                 }
376                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
377                 if (rc < 0 && rc != -ENODATA) {
378                         if (rc == -EOPNOTSUPP)
379                                 printk(KERN_WARNING "SELinux: (dev %s, type "
380                                        "%s) has no security xattr handler\n",
381                                        sb->s_id, sb->s_type->name);
382                         else
383                                 printk(KERN_WARNING "SELinux: (dev %s, type "
384                                        "%s) getxattr errno %d\n", sb->s_id,
385                                        sb->s_type->name, -rc);
386                         goto out;
387                 }
388         }
389
390         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
391
392         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
393                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
394                        sb->s_id, sb->s_type->name);
395         else
396                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
397                        sb->s_id, sb->s_type->name,
398                        labeling_behaviors[sbsec->behavior-1]);
399
400         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
401             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
402             sbsec->behavior == SECURITY_FS_USE_NONE ||
403             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404                 sbsec->flags &= ~SE_SBLABELSUPP;
405
406         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
407         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
408                 sbsec->flags |= SE_SBLABELSUPP;
409
410         /* Initialize the root inode. */
411         rc = inode_doinit_with_dentry(root_inode, root);
412
413         /* Initialize any other inodes associated with the superblock, e.g.
414            inodes created prior to initial policy load or inodes created
415            during get_sb by a pseudo filesystem that directly
416            populates itself. */
417         spin_lock(&sbsec->isec_lock);
418 next_inode:
419         if (!list_empty(&sbsec->isec_head)) {
420                 struct inode_security_struct *isec =
421                                 list_entry(sbsec->isec_head.next,
422                                            struct inode_security_struct, list);
423                 struct inode *inode = isec->inode;
424                 spin_unlock(&sbsec->isec_lock);
425                 inode = igrab(inode);
426                 if (inode) {
427                         if (!IS_PRIVATE(inode))
428                                 inode_doinit(inode);
429                         iput(inode);
430                 }
431                 spin_lock(&sbsec->isec_lock);
432                 list_del_init(&isec->list);
433                 goto next_inode;
434         }
435         spin_unlock(&sbsec->isec_lock);
436 out:
437         return rc;
438 }
439
440 /*
441  * This function should allow an FS to ask what it's mount security
442  * options were so it can use those later for submounts, displaying
443  * mount options, or whatever.
444  */
445 static int selinux_get_mnt_opts(const struct super_block *sb,
446                                 struct security_mnt_opts *opts)
447 {
448         int rc = 0, i;
449         struct superblock_security_struct *sbsec = sb->s_security;
450         char *context = NULL;
451         u32 len;
452         char tmp;
453
454         security_init_mnt_opts(opts);
455
456         if (!(sbsec->flags & SE_SBINITIALIZED))
457                 return -EINVAL;
458
459         if (!ss_initialized)
460                 return -EINVAL;
461
462         tmp = sbsec->flags & SE_MNTMASK;
463         /* count the number of mount options for this sb */
464         for (i = 0; i < 8; i++) {
465                 if (tmp & 0x01)
466                         opts->num_mnt_opts++;
467                 tmp >>= 1;
468         }
469         /* Check if the Label support flag is set */
470         if (sbsec->flags & SE_SBLABELSUPP)
471                 opts->num_mnt_opts++;
472
473         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
474         if (!opts->mnt_opts) {
475                 rc = -ENOMEM;
476                 goto out_free;
477         }
478
479         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
480         if (!opts->mnt_opts_flags) {
481                 rc = -ENOMEM;
482                 goto out_free;
483         }
484
485         i = 0;
486         if (sbsec->flags & FSCONTEXT_MNT) {
487                 rc = security_sid_to_context(sbsec->sid, &context, &len);
488                 if (rc)
489                         goto out_free;
490                 opts->mnt_opts[i] = context;
491                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
492         }
493         if (sbsec->flags & CONTEXT_MNT) {
494                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
495                 if (rc)
496                         goto out_free;
497                 opts->mnt_opts[i] = context;
498                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
499         }
500         if (sbsec->flags & DEFCONTEXT_MNT) {
501                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
502                 if (rc)
503                         goto out_free;
504                 opts->mnt_opts[i] = context;
505                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
506         }
507         if (sbsec->flags & ROOTCONTEXT_MNT) {
508                 struct inode *root = sbsec->sb->s_root->d_inode;
509                 struct inode_security_struct *isec = root->i_security;
510
511                 rc = security_sid_to_context(isec->sid, &context, &len);
512                 if (rc)
513                         goto out_free;
514                 opts->mnt_opts[i] = context;
515                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
516         }
517         if (sbsec->flags & SE_SBLABELSUPP) {
518                 opts->mnt_opts[i] = NULL;
519                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
520         }
521
522         BUG_ON(i != opts->num_mnt_opts);
523
524         return 0;
525
526 out_free:
527         security_free_mnt_opts(opts);
528         return rc;
529 }
530
531 static int bad_option(struct superblock_security_struct *sbsec, char flag,
532                       u32 old_sid, u32 new_sid)
533 {
534         char mnt_flags = sbsec->flags & SE_MNTMASK;
535
536         /* check if the old mount command had the same options */
537         if (sbsec->flags & SE_SBINITIALIZED)
538                 if (!(sbsec->flags & flag) ||
539                     (old_sid != new_sid))
540                         return 1;
541
542         /* check if we were passed the same options twice,
543          * aka someone passed context=a,context=b
544          */
545         if (!(sbsec->flags & SE_SBINITIALIZED))
546                 if (mnt_flags & flag)
547                         return 1;
548         return 0;
549 }
550
551 /*
552  * Allow filesystems with binary mount data to explicitly set mount point
553  * labeling information.
554  */
555 static int selinux_set_mnt_opts(struct super_block *sb,
556                                 struct security_mnt_opts *opts)
557 {
558         const struct cred *cred = current_cred();
559         int rc = 0, i;
560         struct superblock_security_struct *sbsec = sb->s_security;
561         const char *name = sb->s_type->name;
562         struct inode *inode = sbsec->sb->s_root->d_inode;
563         struct inode_security_struct *root_isec = inode->i_security;
564         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
565         u32 defcontext_sid = 0;
566         char **mount_options = opts->mnt_opts;
567         int *flags = opts->mnt_opts_flags;
568         int num_opts = opts->num_mnt_opts;
569
570         mutex_lock(&sbsec->lock);
571
572         if (!ss_initialized) {
573                 if (!num_opts) {
574                         /* Defer initialization until selinux_complete_init,
575                            after the initial policy is loaded and the security
576                            server is ready to handle calls. */
577                         goto out;
578                 }
579                 rc = -EINVAL;
580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581                         "before the security server is initialized\n");
582                 goto out;
583         }
584
585         /*
586          * Binary mount data FS will come through this function twice.  Once
587          * from an explicit call and once from the generic calls from the vfs.
588          * Since the generic VFS calls will not contain any security mount data
589          * we need to skip the double mount verification.
590          *
591          * This does open a hole in which we will not notice if the first
592          * mount using this sb set explict options and a second mount using
593          * this sb does not set any security options.  (The first options
594          * will be used for both mounts)
595          */
596         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597             && (num_opts == 0))
598                 goto out;
599
600         /*
601          * parse the mount options, check if they are valid sids.
602          * also check if someone is trying to mount the same sb more
603          * than once with different security options.
604          */
605         for (i = 0; i < num_opts; i++) {
606                 u32 sid;
607
608                 if (flags[i] == SE_SBLABELSUPP)
609                         continue;
610                 rc = security_context_to_sid(mount_options[i],
611                                              strlen(mount_options[i]), &sid);
612                 if (rc) {
613                         printk(KERN_WARNING "SELinux: security_context_to_sid"
614                                "(%s) failed for (dev %s, type %s) errno=%d\n",
615                                mount_options[i], sb->s_id, name, rc);
616                         goto out;
617                 }
618                 switch (flags[i]) {
619                 case FSCONTEXT_MNT:
620                         fscontext_sid = sid;
621
622                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
623                                         fscontext_sid))
624                                 goto out_double_mount;
625
626                         sbsec->flags |= FSCONTEXT_MNT;
627                         break;
628                 case CONTEXT_MNT:
629                         context_sid = sid;
630
631                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
632                                         context_sid))
633                                 goto out_double_mount;
634
635                         sbsec->flags |= CONTEXT_MNT;
636                         break;
637                 case ROOTCONTEXT_MNT:
638                         rootcontext_sid = sid;
639
640                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
641                                         rootcontext_sid))
642                                 goto out_double_mount;
643
644                         sbsec->flags |= ROOTCONTEXT_MNT;
645
646                         break;
647                 case DEFCONTEXT_MNT:
648                         defcontext_sid = sid;
649
650                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
651                                         defcontext_sid))
652                                 goto out_double_mount;
653
654                         sbsec->flags |= DEFCONTEXT_MNT;
655
656                         break;
657                 default:
658                         rc = -EINVAL;
659                         goto out;
660                 }
661         }
662
663         if (sbsec->flags & SE_SBINITIALIZED) {
664                 /* previously mounted with options, but not on this attempt? */
665                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666                         goto out_double_mount;
667                 rc = 0;
668                 goto out;
669         }
670
671         if (strcmp(sb->s_type->name, "proc") == 0)
672                 sbsec->flags |= SE_SBPROC;
673
674         /* Determine the labeling behavior to use for this filesystem type. */
675         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676         if (rc) {
677                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678                        __func__, sb->s_type->name, rc);
679                 goto out;
680         }
681
682         /* sets the context of the superblock for the fs being mounted. */
683         if (fscontext_sid) {
684                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
685                 if (rc)
686                         goto out;
687
688                 sbsec->sid = fscontext_sid;
689         }
690
691         /*
692          * Switch to using mount point labeling behavior.
693          * sets the label used on all file below the mountpoint, and will set
694          * the superblock context if not already set.
695          */
696         if (context_sid) {
697                 if (!fscontext_sid) {
698                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
699                                                           cred);
700                         if (rc)
701                                 goto out;
702                         sbsec->sid = context_sid;
703                 } else {
704                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
705                                                              cred);
706                         if (rc)
707                                 goto out;
708                 }
709                 if (!rootcontext_sid)
710                         rootcontext_sid = context_sid;
711
712                 sbsec->mntpoint_sid = context_sid;
713                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
714         }
715
716         if (rootcontext_sid) {
717                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
718                                                      cred);
719                 if (rc)
720                         goto out;
721
722                 root_isec->sid = rootcontext_sid;
723                 root_isec->initialized = 1;
724         }
725
726         if (defcontext_sid) {
727                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
728                         rc = -EINVAL;
729                         printk(KERN_WARNING "SELinux: defcontext option is "
730                                "invalid for this filesystem type\n");
731                         goto out;
732                 }
733
734                 if (defcontext_sid != sbsec->def_sid) {
735                         rc = may_context_mount_inode_relabel(defcontext_sid,
736                                                              sbsec, cred);
737                         if (rc)
738                                 goto out;
739                 }
740
741                 sbsec->def_sid = defcontext_sid;
742         }
743
744         rc = sb_finish_set_opts(sb);
745 out:
746         mutex_unlock(&sbsec->lock);
747         return rc;
748 out_double_mount:
749         rc = -EINVAL;
750         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
751                "security settings for (dev %s, type %s)\n", sb->s_id, name);
752         goto out;
753 }
754
755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
756                                         struct super_block *newsb)
757 {
758         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
759         struct superblock_security_struct *newsbsec = newsb->s_security;
760
761         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
762         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
763         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
764
765         /*
766          * if the parent was able to be mounted it clearly had no special lsm
767          * mount options.  thus we can safely deal with this superblock later
768          */
769         if (!ss_initialized)
770                 return;
771
772         /* how can we clone if the old one wasn't set up?? */
773         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774
775         /* if fs is reusing a sb, just let its options stand... */
776         if (newsbsec->flags & SE_SBINITIALIZED)
777                 return;
778
779         mutex_lock(&newsbsec->lock);
780
781         newsbsec->flags = oldsbsec->flags;
782
783         newsbsec->sid = oldsbsec->sid;
784         newsbsec->def_sid = oldsbsec->def_sid;
785         newsbsec->behavior = oldsbsec->behavior;
786
787         if (set_context) {
788                 u32 sid = oldsbsec->mntpoint_sid;
789
790                 if (!set_fscontext)
791                         newsbsec->sid = sid;
792                 if (!set_rootcontext) {
793                         struct inode *newinode = newsb->s_root->d_inode;
794                         struct inode_security_struct *newisec = newinode->i_security;
795                         newisec->sid = sid;
796                 }
797                 newsbsec->mntpoint_sid = sid;
798         }
799         if (set_rootcontext) {
800                 const struct inode *oldinode = oldsb->s_root->d_inode;
801                 const struct inode_security_struct *oldisec = oldinode->i_security;
802                 struct inode *newinode = newsb->s_root->d_inode;
803                 struct inode_security_struct *newisec = newinode->i_security;
804
805                 newisec->sid = oldisec->sid;
806         }
807
808         sb_finish_set_opts(newsb);
809         mutex_unlock(&newsbsec->lock);
810 }
811
812 static int selinux_parse_opts_str(char *options,
813                                   struct security_mnt_opts *opts)
814 {
815         char *p;
816         char *context = NULL, *defcontext = NULL;
817         char *fscontext = NULL, *rootcontext = NULL;
818         int rc, num_mnt_opts = 0;
819
820         opts->num_mnt_opts = 0;
821
822         /* Standard string-based options. */
823         while ((p = strsep(&options, "|")) != NULL) {
824                 int token;
825                 substring_t args[MAX_OPT_ARGS];
826
827                 if (!*p)
828                         continue;
829
830                 token = match_token(p, tokens, args);
831
832                 switch (token) {
833                 case Opt_context:
834                         if (context || defcontext) {
835                                 rc = -EINVAL;
836                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
837                                 goto out_err;
838                         }
839                         context = match_strdup(&args[0]);
840                         if (!context) {
841                                 rc = -ENOMEM;
842                                 goto out_err;
843                         }
844                         break;
845
846                 case Opt_fscontext:
847                         if (fscontext) {
848                                 rc = -EINVAL;
849                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
850                                 goto out_err;
851                         }
852                         fscontext = match_strdup(&args[0]);
853                         if (!fscontext) {
854                                 rc = -ENOMEM;
855                                 goto out_err;
856                         }
857                         break;
858
859                 case Opt_rootcontext:
860                         if (rootcontext) {
861                                 rc = -EINVAL;
862                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
863                                 goto out_err;
864                         }
865                         rootcontext = match_strdup(&args[0]);
866                         if (!rootcontext) {
867                                 rc = -ENOMEM;
868                                 goto out_err;
869                         }
870                         break;
871
872                 case Opt_defcontext:
873                         if (context || defcontext) {
874                                 rc = -EINVAL;
875                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
876                                 goto out_err;
877                         }
878                         defcontext = match_strdup(&args[0]);
879                         if (!defcontext) {
880                                 rc = -ENOMEM;
881                                 goto out_err;
882                         }
883                         break;
884                 case Opt_labelsupport:
885                         break;
886                 default:
887                         rc = -EINVAL;
888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
889                         goto out_err;
890
891                 }
892         }
893
894         rc = -ENOMEM;
895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896         if (!opts->mnt_opts)
897                 goto out_err;
898
899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900         if (!opts->mnt_opts_flags) {
901                 kfree(opts->mnt_opts);
902                 goto out_err;
903         }
904
905         if (fscontext) {
906                 opts->mnt_opts[num_mnt_opts] = fscontext;
907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908         }
909         if (context) {
910                 opts->mnt_opts[num_mnt_opts] = context;
911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912         }
913         if (rootcontext) {
914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916         }
917         if (defcontext) {
918                 opts->mnt_opts[num_mnt_opts] = defcontext;
919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920         }
921
922         opts->num_mnt_opts = num_mnt_opts;
923         return 0;
924
925 out_err:
926         kfree(context);
927         kfree(defcontext);
928         kfree(fscontext);
929         kfree(rootcontext);
930         return rc;
931 }
932 /*
933  * string mount options parsing and call set the sbsec
934  */
935 static int superblock_doinit(struct super_block *sb, void *data)
936 {
937         int rc = 0;
938         char *options = data;
939         struct security_mnt_opts opts;
940
941         security_init_mnt_opts(&opts);
942
943         if (!data)
944                 goto out;
945
946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948         rc = selinux_parse_opts_str(options, &opts);
949         if (rc)
950                 goto out_err;
951
952 out:
953         rc = selinux_set_mnt_opts(sb, &opts);
954
955 out_err:
956         security_free_mnt_opts(&opts);
957         return rc;
958 }
959
960 static void selinux_write_opts(struct seq_file *m,
961                                struct security_mnt_opts *opts)
962 {
963         int i;
964         char *prefix;
965
966         for (i = 0; i < opts->num_mnt_opts; i++) {
967                 char *has_comma;
968
969                 if (opts->mnt_opts[i])
970                         has_comma = strchr(opts->mnt_opts[i], ',');
971                 else
972                         has_comma = NULL;
973
974                 switch (opts->mnt_opts_flags[i]) {
975                 case CONTEXT_MNT:
976                         prefix = CONTEXT_STR;
977                         break;
978                 case FSCONTEXT_MNT:
979                         prefix = FSCONTEXT_STR;
980                         break;
981                 case ROOTCONTEXT_MNT:
982                         prefix = ROOTCONTEXT_STR;
983                         break;
984                 case DEFCONTEXT_MNT:
985                         prefix = DEFCONTEXT_STR;
986                         break;
987                 case SE_SBLABELSUPP:
988                         seq_putc(m, ',');
989                         seq_puts(m, LABELSUPP_STR);
990                         continue;
991                 default:
992                         BUG();
993                         return;
994                 };
995                 /* we need a comma before each option */
996                 seq_putc(m, ',');
997                 seq_puts(m, prefix);
998                 if (has_comma)
999                         seq_putc(m, '\"');
1000                 seq_puts(m, opts->mnt_opts[i]);
1001                 if (has_comma)
1002                         seq_putc(m, '\"');
1003         }
1004 }
1005
1006 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1007 {
1008         struct security_mnt_opts opts;
1009         int rc;
1010
1011         rc = selinux_get_mnt_opts(sb, &opts);
1012         if (rc) {
1013                 /* before policy load we may get EINVAL, don't show anything */
1014                 if (rc == -EINVAL)
1015                         rc = 0;
1016                 return rc;
1017         }
1018
1019         selinux_write_opts(m, &opts);
1020
1021         security_free_mnt_opts(&opts);
1022
1023         return rc;
1024 }
1025
1026 static inline u16 inode_mode_to_security_class(umode_t mode)
1027 {
1028         switch (mode & S_IFMT) {
1029         case S_IFSOCK:
1030                 return SECCLASS_SOCK_FILE;
1031         case S_IFLNK:
1032                 return SECCLASS_LNK_FILE;
1033         case S_IFREG:
1034                 return SECCLASS_FILE;
1035         case S_IFBLK:
1036                 return SECCLASS_BLK_FILE;
1037         case S_IFDIR:
1038                 return SECCLASS_DIR;
1039         case S_IFCHR:
1040                 return SECCLASS_CHR_FILE;
1041         case S_IFIFO:
1042                 return SECCLASS_FIFO_FILE;
1043
1044         }
1045
1046         return SECCLASS_FILE;
1047 }
1048
1049 static inline int default_protocol_stream(int protocol)
1050 {
1051         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1052 }
1053
1054 static inline int default_protocol_dgram(int protocol)
1055 {
1056         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1057 }
1058
1059 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1060 {
1061         switch (family) {
1062         case PF_UNIX:
1063                 switch (type) {
1064                 case SOCK_STREAM:
1065                 case SOCK_SEQPACKET:
1066                         return SECCLASS_UNIX_STREAM_SOCKET;
1067                 case SOCK_DGRAM:
1068                         return SECCLASS_UNIX_DGRAM_SOCKET;
1069                 }
1070                 break;
1071         case PF_INET:
1072         case PF_INET6:
1073                 switch (type) {
1074                 case SOCK_STREAM:
1075                         if (default_protocol_stream(protocol))
1076                                 return SECCLASS_TCP_SOCKET;
1077                         else
1078                                 return SECCLASS_RAWIP_SOCKET;
1079                 case SOCK_DGRAM:
1080                         if (default_protocol_dgram(protocol))
1081                                 return SECCLASS_UDP_SOCKET;
1082                         else
1083                                 return SECCLASS_RAWIP_SOCKET;
1084                 case SOCK_DCCP:
1085                         return SECCLASS_DCCP_SOCKET;
1086                 default:
1087                         return SECCLASS_RAWIP_SOCKET;
1088                 }
1089                 break;
1090         case PF_NETLINK:
1091                 switch (protocol) {
1092                 case NETLINK_ROUTE:
1093                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1094                 case NETLINK_FIREWALL:
1095                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1096                 case NETLINK_INET_DIAG:
1097                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1098                 case NETLINK_NFLOG:
1099                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1100                 case NETLINK_XFRM:
1101                         return SECCLASS_NETLINK_XFRM_SOCKET;
1102                 case NETLINK_SELINUX:
1103                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1104                 case NETLINK_AUDIT:
1105                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1106                 case NETLINK_IP6_FW:
1107                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1108                 case NETLINK_DNRTMSG:
1109                         return SECCLASS_NETLINK_DNRT_SOCKET;
1110                 case NETLINK_KOBJECT_UEVENT:
1111                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1112                 default:
1113                         return SECCLASS_NETLINK_SOCKET;
1114                 }
1115         case PF_PACKET:
1116                 return SECCLASS_PACKET_SOCKET;
1117         case PF_KEY:
1118                 return SECCLASS_KEY_SOCKET;
1119         case PF_APPLETALK:
1120                 return SECCLASS_APPLETALK_SOCKET;
1121         }
1122
1123         return SECCLASS_SOCKET;
1124 }
1125
1126 #ifdef CONFIG_PROC_FS
1127 static int selinux_proc_get_sid(struct dentry *dentry,
1128                                 u16 tclass,
1129                                 u32 *sid)
1130 {
1131         int rc;
1132         char *buffer, *path;
1133
1134         buffer = (char *)__get_free_page(GFP_KERNEL);
1135         if (!buffer)
1136                 return -ENOMEM;
1137
1138         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1139         if (IS_ERR(path))
1140                 rc = PTR_ERR(path);
1141         else {
1142                 /* each process gets a /proc/PID/ entry. Strip off the
1143                  * PID part to get a valid selinux labeling.
1144                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1145                 while (path[1] >= '0' && path[1] <= '9') {
1146                         path[1] = '/';
1147                         path++;
1148                 }
1149                 rc = security_genfs_sid("proc", path, tclass, sid);
1150         }
1151         free_page((unsigned long)buffer);
1152         return rc;
1153 }
1154 #else
1155 static int selinux_proc_get_sid(struct dentry *dentry,
1156                                 u16 tclass,
1157                                 u32 *sid)
1158 {
1159         return -EINVAL;
1160 }
1161 #endif
1162
1163 /* The inode's security attributes must be initialized before first use. */
1164 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165 {
1166         struct superblock_security_struct *sbsec = NULL;
1167         struct inode_security_struct *isec = inode->i_security;
1168         u32 sid;
1169         struct dentry *dentry;
1170 #define INITCONTEXTLEN 255
1171         char *context = NULL;
1172         unsigned len = 0;
1173         int rc = 0;
1174
1175         if (isec->initialized)
1176                 goto out;
1177
1178         mutex_lock(&isec->lock);
1179         if (isec->initialized)
1180                 goto out_unlock;
1181
1182         sbsec = inode->i_sb->s_security;
1183         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184                 /* Defer initialization until selinux_complete_init,
1185                    after the initial policy is loaded and the security
1186                    server is ready to handle calls. */
1187                 spin_lock(&sbsec->isec_lock);
1188                 if (list_empty(&isec->list))
1189                         list_add(&isec->list, &sbsec->isec_head);
1190                 spin_unlock(&sbsec->isec_lock);
1191                 goto out_unlock;
1192         }
1193
1194         switch (sbsec->behavior) {
1195         case SECURITY_FS_USE_XATTR:
1196                 if (!inode->i_op->getxattr) {
1197                         isec->sid = sbsec->def_sid;
1198                         break;
1199                 }
1200
1201                 /* Need a dentry, since the xattr API requires one.
1202                    Life would be simpler if we could just pass the inode. */
1203                 if (opt_dentry) {
1204                         /* Called from d_instantiate or d_splice_alias. */
1205                         dentry = dget(opt_dentry);
1206                 } else {
1207                         /* Called from selinux_complete_init, try to find a dentry. */
1208                         dentry = d_find_alias(inode);
1209                 }
1210                 if (!dentry) {
1211                         /*
1212                          * this is can be hit on boot when a file is accessed
1213                          * before the policy is loaded.  When we load policy we
1214                          * may find inodes that have no dentry on the
1215                          * sbsec->isec_head list.  No reason to complain as these
1216                          * will get fixed up the next time we go through
1217                          * inode_doinit with a dentry, before these inodes could
1218                          * be used again by userspace.
1219                          */
1220                         goto out_unlock;
1221                 }
1222
1223                 len = INITCONTEXTLEN;
1224                 context = kmalloc(len+1, GFP_NOFS);
1225                 if (!context) {
1226                         rc = -ENOMEM;
1227                         dput(dentry);
1228                         goto out_unlock;
1229                 }
1230                 context[len] = '\0';
1231                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232                                            context, len);
1233                 if (rc == -ERANGE) {
1234                         kfree(context);
1235
1236                         /* Need a larger buffer.  Query for the right size. */
1237                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238                                                    NULL, 0);
1239                         if (rc < 0) {
1240                                 dput(dentry);
1241                                 goto out_unlock;
1242                         }
1243                         len = rc;
1244                         context = kmalloc(len+1, GFP_NOFS);
1245                         if (!context) {
1246                                 rc = -ENOMEM;
1247                                 dput(dentry);
1248                                 goto out_unlock;
1249                         }
1250                         context[len] = '\0';
1251                         rc = inode->i_op->getxattr(dentry,
1252                                                    XATTR_NAME_SELINUX,
1253                                                    context, len);
1254                 }
1255                 dput(dentry);
1256                 if (rc < 0) {
1257                         if (rc != -ENODATA) {
1258                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1259                                        "%d for dev=%s ino=%ld\n", __func__,
1260                                        -rc, inode->i_sb->s_id, inode->i_ino);
1261                                 kfree(context);
1262                                 goto out_unlock;
1263                         }
1264                         /* Map ENODATA to the default file SID */
1265                         sid = sbsec->def_sid;
1266                         rc = 0;
1267                 } else {
1268                         rc = security_context_to_sid_default(context, rc, &sid,
1269                                                              sbsec->def_sid,
1270                                                              GFP_NOFS);
1271                         if (rc) {
1272                                 char *dev = inode->i_sb->s_id;
1273                                 unsigned long ino = inode->i_ino;
1274
1275                                 if (rc == -EINVAL) {
1276                                         if (printk_ratelimit())
1277                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1279                                                         "filesystem in question.\n", ino, dev, context);
1280                                 } else {
1281                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1282                                                "returned %d for dev=%s ino=%ld\n",
1283                                                __func__, context, -rc, dev, ino);
1284                                 }
1285                                 kfree(context);
1286                                 /* Leave with the unlabeled SID */
1287                                 rc = 0;
1288                                 break;
1289                         }
1290                 }
1291                 kfree(context);
1292                 isec->sid = sid;
1293                 break;
1294         case SECURITY_FS_USE_TASK:
1295                 isec->sid = isec->task_sid;
1296                 break;
1297         case SECURITY_FS_USE_TRANS:
1298                 /* Default to the fs SID. */
1299                 isec->sid = sbsec->sid;
1300
1301                 /* Try to obtain a transition SID. */
1302                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1304                                              isec->sclass, NULL, &sid);
1305                 if (rc)
1306                         goto out_unlock;
1307                 isec->sid = sid;
1308                 break;
1309         case SECURITY_FS_USE_MNTPOINT:
1310                 isec->sid = sbsec->mntpoint_sid;
1311                 break;
1312         default:
1313                 /* Default to the fs superblock SID. */
1314                 isec->sid = sbsec->sid;
1315
1316                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1317                         if (opt_dentry) {
1318                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1319                                 rc = selinux_proc_get_sid(opt_dentry,
1320                                                           isec->sclass,
1321                                                           &sid);
1322                                 if (rc)
1323                                         goto out_unlock;
1324                                 isec->sid = sid;
1325                         }
1326                 }
1327                 break;
1328         }
1329
1330         isec->initialized = 1;
1331
1332 out_unlock:
1333         mutex_unlock(&isec->lock);
1334 out:
1335         if (isec->sclass == SECCLASS_FILE)
1336                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1337         return rc;
1338 }
1339
1340 /* Convert a Linux signal to an access vector. */
1341 static inline u32 signal_to_av(int sig)
1342 {
1343         u32 perm = 0;
1344
1345         switch (sig) {
1346         case SIGCHLD:
1347                 /* Commonly granted from child to parent. */
1348                 perm = PROCESS__SIGCHLD;
1349                 break;
1350         case SIGKILL:
1351                 /* Cannot be caught or ignored */
1352                 perm = PROCESS__SIGKILL;
1353                 break;
1354         case SIGSTOP:
1355                 /* Cannot be caught or ignored */
1356                 perm = PROCESS__SIGSTOP;
1357                 break;
1358         default:
1359                 /* All other signals. */
1360                 perm = PROCESS__SIGNAL;
1361                 break;
1362         }
1363
1364         return perm;
1365 }
1366
1367 /*
1368  * Check permission between a pair of credentials
1369  * fork check, ptrace check, etc.
1370  */
1371 static int cred_has_perm(const struct cred *actor,
1372                          const struct cred *target,
1373                          u32 perms)
1374 {
1375         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1376
1377         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1378 }
1379
1380 /*
1381  * Check permission between a pair of tasks, e.g. signal checks,
1382  * fork check, ptrace check, etc.
1383  * tsk1 is the actor and tsk2 is the target
1384  * - this uses the default subjective creds of tsk1
1385  */
1386 static int task_has_perm(const struct task_struct *tsk1,
1387                          const struct task_struct *tsk2,
1388                          u32 perms)
1389 {
1390         const struct task_security_struct *__tsec1, *__tsec2;
1391         u32 sid1, sid2;
1392
1393         rcu_read_lock();
1394         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1395         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1396         rcu_read_unlock();
1397         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1398 }
1399
1400 /*
1401  * Check permission between current and another task, e.g. signal checks,
1402  * fork check, ptrace check, etc.
1403  * current is the actor and tsk2 is the target
1404  * - this uses current's subjective creds
1405  */
1406 static int current_has_perm(const struct task_struct *tsk,
1407                             u32 perms)
1408 {
1409         u32 sid, tsid;
1410
1411         sid = current_sid();
1412         tsid = task_sid(tsk);
1413         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1414 }
1415
1416 #if CAP_LAST_CAP > 63
1417 #error Fix SELinux to handle capabilities > 63.
1418 #endif
1419
1420 /* Check whether a task is allowed to use a capability. */
1421 static int task_has_capability(struct task_struct *tsk,
1422                                const struct cred *cred,
1423                                int cap, int audit)
1424 {
1425         struct common_audit_data ad;
1426         struct av_decision avd;
1427         u16 sclass;
1428         u32 sid = cred_sid(cred);
1429         u32 av = CAP_TO_MASK(cap);
1430         int rc;
1431
1432         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1433         ad.tsk = tsk;
1434         ad.u.cap = cap;
1435
1436         switch (CAP_TO_INDEX(cap)) {
1437         case 0:
1438                 sclass = SECCLASS_CAPABILITY;
1439                 break;
1440         case 1:
1441                 sclass = SECCLASS_CAPABILITY2;
1442                 break;
1443         default:
1444                 printk(KERN_ERR
1445                        "SELinux:  out of range capability %d\n", cap);
1446                 BUG();
1447                 return -EINVAL;
1448         }
1449
1450         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1451         if (audit == SECURITY_CAP_AUDIT) {
1452                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1453                 if (rc2)
1454                         return rc2;
1455         }
1456         return rc;
1457 }
1458
1459 /* Check whether a task is allowed to use a system operation. */
1460 static int task_has_system(struct task_struct *tsk,
1461                            u32 perms)
1462 {
1463         u32 sid = task_sid(tsk);
1464
1465         return avc_has_perm(sid, SECINITSID_KERNEL,
1466                             SECCLASS_SYSTEM, perms, NULL);
1467 }
1468
1469 /* Check whether a task has a particular permission to an inode.
1470    The 'adp' parameter is optional and allows other audit
1471    data to be passed (e.g. the dentry). */
1472 static int inode_has_perm(const struct cred *cred,
1473                           struct inode *inode,
1474                           u32 perms,
1475                           struct common_audit_data *adp,
1476                           unsigned flags)
1477 {
1478         struct inode_security_struct *isec;
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         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1490 }
1491
1492 static int inode_has_perm_noadp(const struct cred *cred,
1493                                 struct inode *inode,
1494                                 u32 perms,
1495                                 unsigned flags)
1496 {
1497         struct common_audit_data ad;
1498
1499         COMMON_AUDIT_DATA_INIT(&ad, INODE);
1500         ad.u.inode = inode;
1501         return inode_has_perm(cred, inode, perms, &ad, flags);
1502 }
1503
1504 /* Same as inode_has_perm, but pass explicit audit data containing
1505    the dentry to help the auditing code to more easily generate the
1506    pathname if needed. */
1507 static inline int dentry_has_perm(const struct cred *cred,
1508                                   struct dentry *dentry,
1509                                   u32 av)
1510 {
1511         struct inode *inode = dentry->d_inode;
1512         struct common_audit_data ad;
1513
1514         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1515         ad.u.dentry = dentry;
1516         return inode_has_perm(cred, inode, av, &ad, 0);
1517 }
1518
1519 /* Same as inode_has_perm, but pass explicit audit data containing
1520    the path to help the auditing code to more easily generate the
1521    pathname if needed. */
1522 static inline int path_has_perm(const struct cred *cred,
1523                                 struct path *path,
1524                                 u32 av)
1525 {
1526         struct inode *inode = path->dentry->d_inode;
1527         struct common_audit_data ad;
1528
1529         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1530         ad.u.path = *path;
1531         return inode_has_perm(cred, inode, av, &ad, 0);
1532 }
1533
1534 /* Check whether a task can use an open file descriptor to
1535    access an inode in a given way.  Check access to the
1536    descriptor itself, and then use dentry_has_perm to
1537    check a particular permission to the file.
1538    Access to the descriptor is implicitly granted if it
1539    has the same SID as the process.  If av is zero, then
1540    access to the file is not checked, e.g. for cases
1541    where only the descriptor is affected like seek. */
1542 static int file_has_perm(const struct cred *cred,
1543                          struct file *file,
1544                          u32 av)
1545 {
1546         struct file_security_struct *fsec = file->f_security;
1547         struct inode *inode = file->f_path.dentry->d_inode;
1548         struct common_audit_data ad;
1549         u32 sid = cred_sid(cred);
1550         int rc;
1551
1552         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1553         ad.u.path = file->f_path;
1554
1555         if (sid != fsec->sid) {
1556                 rc = avc_has_perm(sid, fsec->sid,
1557                                   SECCLASS_FD,
1558                                   FD__USE,
1559                                   &ad);
1560                 if (rc)
1561                         goto out;
1562         }
1563
1564         /* av is zero if only checking access to the descriptor. */
1565         rc = 0;
1566         if (av)
1567                 rc = inode_has_perm(cred, inode, av, &ad, 0);
1568
1569 out:
1570         return rc;
1571 }
1572
1573 /* Check whether a task can create a file. */
1574 static int may_create(struct inode *dir,
1575                       struct dentry *dentry,
1576                       u16 tclass)
1577 {
1578         const struct task_security_struct *tsec = current_security();
1579         struct inode_security_struct *dsec;
1580         struct superblock_security_struct *sbsec;
1581         u32 sid, newsid;
1582         struct common_audit_data ad;
1583         int rc;
1584
1585         dsec = dir->i_security;
1586         sbsec = dir->i_sb->s_security;
1587
1588         sid = tsec->sid;
1589         newsid = tsec->create_sid;
1590
1591         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1592         ad.u.dentry = dentry;
1593
1594         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1595                           DIR__ADD_NAME | DIR__SEARCH,
1596                           &ad);
1597         if (rc)
1598                 return rc;
1599
1600         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1601                 rc = security_transition_sid(sid, dsec->sid, tclass,
1602                                              &dentry->d_name, &newsid);
1603                 if (rc)
1604                         return rc;
1605         }
1606
1607         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1608         if (rc)
1609                 return rc;
1610
1611         return avc_has_perm(newsid, sbsec->sid,
1612                             SECCLASS_FILESYSTEM,
1613                             FILESYSTEM__ASSOCIATE, &ad);
1614 }
1615
1616 /* Check whether a task can create a key. */
1617 static int may_create_key(u32 ksid,
1618                           struct task_struct *ctx)
1619 {
1620         u32 sid = task_sid(ctx);
1621
1622         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1623 }
1624
1625 #define MAY_LINK        0
1626 #define MAY_UNLINK      1
1627 #define MAY_RMDIR       2
1628
1629 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1630 static int may_link(struct inode *dir,
1631                     struct dentry *dentry,
1632                     int kind)
1633
1634 {
1635         struct inode_security_struct *dsec, *isec;
1636         struct common_audit_data ad;
1637         u32 sid = current_sid();
1638         u32 av;
1639         int rc;
1640
1641         dsec = dir->i_security;
1642         isec = dentry->d_inode->i_security;
1643
1644         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1645         ad.u.dentry = dentry;
1646
1647         av = DIR__SEARCH;
1648         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1649         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1650         if (rc)
1651                 return rc;
1652
1653         switch (kind) {
1654         case MAY_LINK:
1655                 av = FILE__LINK;
1656                 break;
1657         case MAY_UNLINK:
1658                 av = FILE__UNLINK;
1659                 break;
1660         case MAY_RMDIR:
1661                 av = DIR__RMDIR;
1662                 break;
1663         default:
1664                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1665                         __func__, kind);
1666                 return 0;
1667         }
1668
1669         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1670         return rc;
1671 }
1672
1673 static inline int may_rename(struct inode *old_dir,
1674                              struct dentry *old_dentry,
1675                              struct inode *new_dir,
1676                              struct dentry *new_dentry)
1677 {
1678         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1679         struct common_audit_data ad;
1680         u32 sid = current_sid();
1681         u32 av;
1682         int old_is_dir, new_is_dir;
1683         int rc;
1684
1685         old_dsec = old_dir->i_security;
1686         old_isec = old_dentry->d_inode->i_security;
1687         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1688         new_dsec = new_dir->i_security;
1689
1690         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1691
1692         ad.u.dentry = old_dentry;
1693         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1694                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1695         if (rc)
1696                 return rc;
1697         rc = avc_has_perm(sid, old_isec->sid,
1698                           old_isec->sclass, FILE__RENAME, &ad);
1699         if (rc)
1700                 return rc;
1701         if (old_is_dir && new_dir != old_dir) {
1702                 rc = avc_has_perm(sid, old_isec->sid,
1703                                   old_isec->sclass, DIR__REPARENT, &ad);
1704                 if (rc)
1705                         return rc;
1706         }
1707
1708         ad.u.dentry = new_dentry;
1709         av = DIR__ADD_NAME | DIR__SEARCH;
1710         if (new_dentry->d_inode)
1711                 av |= DIR__REMOVE_NAME;
1712         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1713         if (rc)
1714                 return rc;
1715         if (new_dentry->d_inode) {
1716                 new_isec = new_dentry->d_inode->i_security;
1717                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1718                 rc = avc_has_perm(sid, new_isec->sid,
1719                                   new_isec->sclass,
1720                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1721                 if (rc)
1722                         return rc;
1723         }
1724
1725         return 0;
1726 }
1727
1728 /* Check whether a task can perform a filesystem operation. */
1729 static int superblock_has_perm(const struct cred *cred,
1730                                struct super_block *sb,
1731                                u32 perms,
1732                                struct common_audit_data *ad)
1733 {
1734         struct superblock_security_struct *sbsec;
1735         u32 sid = cred_sid(cred);
1736
1737         sbsec = sb->s_security;
1738         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1739 }
1740
1741 /* Convert a Linux mode and permission mask to an access vector. */
1742 static inline u32 file_mask_to_av(int mode, int mask)
1743 {
1744         u32 av = 0;
1745
1746         if ((mode & S_IFMT) != S_IFDIR) {
1747                 if (mask & MAY_EXEC)
1748                         av |= FILE__EXECUTE;
1749                 if (mask & MAY_READ)
1750                         av |= FILE__READ;
1751
1752                 if (mask & MAY_APPEND)
1753                         av |= FILE__APPEND;
1754                 else if (mask & MAY_WRITE)
1755                         av |= FILE__WRITE;
1756
1757         } else {
1758                 if (mask & MAY_EXEC)
1759                         av |= DIR__SEARCH;
1760                 if (mask & MAY_WRITE)
1761                         av |= DIR__WRITE;
1762                 if (mask & MAY_READ)
1763                         av |= DIR__READ;
1764         }
1765
1766         return av;
1767 }
1768
1769 /* Convert a Linux file to an access vector. */
1770 static inline u32 file_to_av(struct file *file)
1771 {
1772         u32 av = 0;
1773
1774         if (file->f_mode & FMODE_READ)
1775                 av |= FILE__READ;
1776         if (file->f_mode & FMODE_WRITE) {
1777                 if (file->f_flags & O_APPEND)
1778                         av |= FILE__APPEND;
1779                 else
1780                         av |= FILE__WRITE;
1781         }
1782         if (!av) {
1783                 /*
1784                  * Special file opened with flags 3 for ioctl-only use.
1785                  */
1786                 av = FILE__IOCTL;
1787         }
1788
1789         return av;
1790 }
1791
1792 /*
1793  * Convert a file to an access vector and include the correct open
1794  * open permission.
1795  */
1796 static inline u32 open_file_to_av(struct file *file)
1797 {
1798         u32 av = file_to_av(file);
1799
1800         if (selinux_policycap_openperm)
1801                 av |= FILE__OPEN;
1802
1803         return av;
1804 }
1805
1806 /* Hook functions begin here. */
1807
1808 static int selinux_ptrace_access_check(struct task_struct *child,
1809                                      unsigned int mode)
1810 {
1811         int rc;
1812
1813         rc = cap_ptrace_access_check(child, mode);
1814         if (rc)
1815                 return rc;
1816
1817         if (mode == PTRACE_MODE_READ) {
1818                 u32 sid = current_sid();
1819                 u32 csid = task_sid(child);
1820                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1821         }
1822
1823         return current_has_perm(child, PROCESS__PTRACE);
1824 }
1825
1826 static int selinux_ptrace_traceme(struct task_struct *parent)
1827 {
1828         int rc;
1829
1830         rc = cap_ptrace_traceme(parent);
1831         if (rc)
1832                 return rc;
1833
1834         return task_has_perm(parent, current, PROCESS__PTRACE);
1835 }
1836
1837 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1838                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1839 {
1840         int error;
1841
1842         error = current_has_perm(target, PROCESS__GETCAP);
1843         if (error)
1844                 return error;
1845
1846         return cap_capget(target, effective, inheritable, permitted);
1847 }
1848
1849 static int selinux_capset(struct cred *new, const struct cred *old,
1850                           const kernel_cap_t *effective,
1851                           const kernel_cap_t *inheritable,
1852                           const kernel_cap_t *permitted)
1853 {
1854         int error;
1855
1856         error = cap_capset(new, old,
1857                                       effective, inheritable, permitted);
1858         if (error)
1859                 return error;
1860
1861         return cred_has_perm(old, new, PROCESS__SETCAP);
1862 }
1863
1864 /*
1865  * (This comment used to live with the selinux_task_setuid hook,
1866  * which was removed).
1867  *
1868  * Since setuid only affects the current process, and since the SELinux
1869  * controls are not based on the Linux identity attributes, SELinux does not
1870  * need to control this operation.  However, SELinux does control the use of
1871  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1872  */
1873
1874 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1875                            struct user_namespace *ns, int cap, int audit)
1876 {
1877         int rc;
1878
1879         rc = cap_capable(tsk, cred, ns, cap, audit);
1880         if (rc)
1881                 return rc;
1882
1883         return task_has_capability(tsk, cred, cap, audit);
1884 }
1885
1886 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1887 {
1888         const struct cred *cred = current_cred();
1889         int rc = 0;
1890
1891         if (!sb)
1892                 return 0;
1893
1894         switch (cmds) {
1895         case Q_SYNC:
1896         case Q_QUOTAON:
1897         case Q_QUOTAOFF:
1898         case Q_SETINFO:
1899         case Q_SETQUOTA:
1900                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1901                 break;
1902         case Q_GETFMT:
1903         case Q_GETINFO:
1904         case Q_GETQUOTA:
1905                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1906                 break;
1907         default:
1908                 rc = 0;  /* let the kernel handle invalid cmds */
1909                 break;
1910         }
1911         return rc;
1912 }
1913
1914 static int selinux_quota_on(struct dentry *dentry)
1915 {
1916         const struct cred *cred = current_cred();
1917
1918         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1919 }
1920
1921 static int selinux_syslog(int type)
1922 {
1923         int rc;
1924
1925         switch (type) {
1926         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1927         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1928                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1929                 break;
1930         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1931         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1932         /* Set level of messages printed to console */
1933         case SYSLOG_ACTION_CONSOLE_LEVEL:
1934                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1935                 break;
1936         case SYSLOG_ACTION_CLOSE:       /* Close log */
1937         case SYSLOG_ACTION_OPEN:        /* Open log */
1938         case SYSLOG_ACTION_READ:        /* Read from log */
1939         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1940         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1941         default:
1942                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1943                 break;
1944         }
1945         return rc;
1946 }
1947
1948 /*
1949  * Check that a process has enough memory to allocate a new virtual
1950  * mapping. 0 means there is enough memory for the allocation to
1951  * succeed and -ENOMEM implies there is not.
1952  *
1953  * Do not audit the selinux permission check, as this is applied to all
1954  * processes that allocate mappings.
1955  */
1956 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1957 {
1958         int rc, cap_sys_admin = 0;
1959
1960         rc = selinux_capable(current, current_cred(),
1961                              &init_user_ns, CAP_SYS_ADMIN,
1962                              SECURITY_CAP_NOAUDIT);
1963         if (rc == 0)
1964                 cap_sys_admin = 1;
1965
1966         return __vm_enough_memory(mm, pages, cap_sys_admin);
1967 }
1968
1969 /* binprm security operations */
1970
1971 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1972 {
1973         const struct task_security_struct *old_tsec;
1974         struct task_security_struct *new_tsec;
1975         struct inode_security_struct *isec;
1976         struct common_audit_data ad;
1977         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1978         int rc;
1979
1980         rc = cap_bprm_set_creds(bprm);
1981         if (rc)
1982                 return rc;
1983
1984         /* SELinux context only depends on initial program or script and not
1985          * the script interpreter */
1986         if (bprm->cred_prepared)
1987                 return 0;
1988
1989         old_tsec = current_security();
1990         new_tsec = bprm->cred->security;
1991         isec = inode->i_security;
1992
1993         /* Default to the current task SID. */
1994         new_tsec->sid = old_tsec->sid;
1995         new_tsec->osid = old_tsec->sid;
1996
1997         /* Reset fs, key, and sock SIDs on execve. */
1998         new_tsec->create_sid = 0;
1999         new_tsec->keycreate_sid = 0;
2000         new_tsec->sockcreate_sid = 0;
2001
2002         if (old_tsec->exec_sid) {
2003                 new_tsec->sid = old_tsec->exec_sid;
2004                 /* Reset exec SID on execve. */
2005                 new_tsec->exec_sid = 0;
2006         } else {
2007                 /* Check for a default transition on this program. */
2008                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2009                                              SECCLASS_PROCESS, NULL,
2010                                              &new_tsec->sid);
2011                 if (rc)
2012                         return rc;
2013         }
2014
2015         COMMON_AUDIT_DATA_INIT(&ad, PATH);
2016         ad.u.path = bprm->file->f_path;
2017
2018         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2019                 new_tsec->sid = old_tsec->sid;
2020
2021         if (new_tsec->sid == old_tsec->sid) {
2022                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2023                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2024                 if (rc)
2025                         return rc;
2026         } else {
2027                 /* Check permissions for the transition. */
2028                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2029                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2030                 if (rc)
2031                         return rc;
2032
2033                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2034                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2035                 if (rc)
2036                         return rc;
2037
2038                 /* Check for shared state */
2039                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2040                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2041                                           SECCLASS_PROCESS, PROCESS__SHARE,
2042                                           NULL);
2043                         if (rc)
2044                                 return -EPERM;
2045                 }
2046
2047                 /* Make sure that anyone attempting to ptrace over a task that
2048                  * changes its SID has the appropriate permit */
2049                 if (bprm->unsafe &
2050                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2051                         struct task_struct *tracer;
2052                         struct task_security_struct *sec;
2053                         u32 ptsid = 0;
2054
2055                         rcu_read_lock();
2056                         tracer = tracehook_tracer_task(current);
2057                         if (likely(tracer != NULL)) {
2058                                 sec = __task_cred(tracer)->security;
2059                                 ptsid = sec->sid;
2060                         }
2061                         rcu_read_unlock();
2062
2063                         if (ptsid != 0) {
2064                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2065                                                   SECCLASS_PROCESS,
2066                                                   PROCESS__PTRACE, NULL);
2067                                 if (rc)
2068                                         return -EPERM;
2069                         }
2070                 }
2071
2072                 /* Clear any possibly unsafe personality bits on exec: */
2073                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2074         }
2075
2076         return 0;
2077 }
2078
2079 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2080 {
2081         const struct task_security_struct *tsec = current_security();
2082         u32 sid, osid;
2083         int atsecure = 0;
2084
2085         sid = tsec->sid;
2086         osid = tsec->osid;
2087
2088         if (osid != sid) {
2089                 /* Enable secure mode for SIDs transitions unless
2090                    the noatsecure permission is granted between
2091                    the two SIDs, i.e. ahp returns 0. */
2092                 atsecure = avc_has_perm(osid, sid,
2093                                         SECCLASS_PROCESS,
2094                                         PROCESS__NOATSECURE, NULL);
2095         }
2096
2097         return (atsecure || cap_bprm_secureexec(bprm));
2098 }
2099
2100 extern struct vfsmount *selinuxfs_mount;
2101 extern struct dentry *selinux_null;
2102
2103 /* Derived from fs/exec.c:flush_old_files. */
2104 static inline void flush_unauthorized_files(const struct cred *cred,
2105                                             struct files_struct *files)
2106 {
2107         struct common_audit_data ad;
2108         struct file *file, *devnull = NULL;
2109         struct tty_struct *tty;
2110         struct fdtable *fdt;
2111         long j = -1;
2112         int drop_tty = 0;
2113
2114         tty = get_current_tty();
2115         if (tty) {
2116                 spin_lock(&tty_files_lock);
2117                 if (!list_empty(&tty->tty_files)) {
2118                         struct tty_file_private *file_priv;
2119                         struct inode *inode;
2120
2121                         /* Revalidate access to controlling tty.
2122                            Use inode_has_perm on the tty inode directly rather
2123                            than using file_has_perm, as this particular open
2124                            file may belong to another process and we are only
2125                            interested in the inode-based check here. */
2126                         file_priv = list_first_entry(&tty->tty_files,
2127                                                 struct tty_file_private, list);
2128                         file = file_priv->file;
2129                         inode = file->f_path.dentry->d_inode;
2130                         if (inode_has_perm_noadp(cred, inode,
2131                                            FILE__READ | FILE__WRITE, 0)) {
2132                                 drop_tty = 1;
2133                         }
2134                 }
2135                 spin_unlock(&tty_files_lock);
2136                 tty_kref_put(tty);
2137         }
2138         /* Reset controlling tty. */
2139         if (drop_tty)
2140                 no_tty();
2141
2142         /* Revalidate access to inherited open files. */
2143
2144         COMMON_AUDIT_DATA_INIT(&ad, INODE);
2145
2146         spin_lock(&files->file_lock);
2147         for (;;) {
2148                 unsigned long set, i;
2149                 int fd;
2150
2151                 j++;
2152                 i = j * __NFDBITS;
2153                 fdt = files_fdtable(files);
2154                 if (i >= fdt->max_fds)
2155                         break;
2156                 set = fdt->open_fds->fds_bits[j];
2157                 if (!set)
2158                         continue;
2159                 spin_unlock(&files->file_lock);
2160                 for ( ; set ; i++, set >>= 1) {
2161                         if (set & 1) {
2162                                 file = fget(i);
2163                                 if (!file)
2164                                         continue;
2165                                 if (file_has_perm(cred,
2166                                                   file,
2167                                                   file_to_av(file))) {
2168                                         sys_close(i);
2169                                         fd = get_unused_fd();
2170                                         if (fd != i) {
2171                                                 if (fd >= 0)
2172                                                         put_unused_fd(fd);
2173                                                 fput(file);
2174                                                 continue;
2175                                         }
2176                                         if (devnull) {
2177                                                 get_file(devnull);
2178                                         } else {
2179                                                 devnull = dentry_open(
2180                                                         dget(selinux_null),
2181                                                         mntget(selinuxfs_mount),
2182                                                         O_RDWR, cred);
2183                                                 if (IS_ERR(devnull)) {
2184                                                         devnull = NULL;
2185                                                         put_unused_fd(fd);
2186                                                         fput(file);
2187                                                         continue;
2188                                                 }
2189                                         }
2190                                         fd_install(fd, devnull);
2191                                 }
2192                                 fput(file);
2193                         }
2194                 }
2195                 spin_lock(&files->file_lock);
2196
2197         }
2198         spin_unlock(&files->file_lock);
2199 }
2200
2201 /*
2202  * Prepare a process for imminent new credential changes due to exec
2203  */
2204 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2205 {
2206         struct task_security_struct *new_tsec;
2207         struct rlimit *rlim, *initrlim;
2208         int rc, i;
2209
2210         new_tsec = bprm->cred->security;
2211         if (new_tsec->sid == new_tsec->osid)
2212                 return;
2213
2214         /* Close files for which the new task SID is not authorized. */
2215         flush_unauthorized_files(bprm->cred, current->files);
2216
2217         /* Always clear parent death signal on SID transitions. */
2218         current->pdeath_signal = 0;
2219
2220         /* Check whether the new SID can inherit resource limits from the old
2221          * SID.  If not, reset all soft limits to the lower of the current
2222          * task's hard limit and the init task's soft limit.
2223          *
2224          * Note that the setting of hard limits (even to lower them) can be
2225          * controlled by the setrlimit check.  The inclusion of the init task's
2226          * soft limit into the computation is to avoid resetting soft limits
2227          * higher than the default soft limit for cases where the default is
2228          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2229          */
2230         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2231                           PROCESS__RLIMITINH, NULL);
2232         if (rc) {
2233                 /* protect against do_prlimit() */
2234                 task_lock(current);
2235                 for (i = 0; i < RLIM_NLIMITS; i++) {
2236                         rlim = current->signal->rlim + i;
2237                         initrlim = init_task.signal->rlim + i;
2238                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2239                 }
2240                 task_unlock(current);
2241                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2242         }
2243 }
2244
2245 /*
2246  * Clean up the process immediately after the installation of new credentials
2247  * due to exec
2248  */
2249 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2250 {
2251         const struct task_security_struct *tsec = current_security();
2252         struct itimerval itimer;
2253         u32 osid, sid;
2254         int rc, i;
2255
2256         osid = tsec->osid;
2257         sid = tsec->sid;
2258
2259         if (sid == osid)
2260                 return;
2261
2262         /* Check whether the new SID can inherit signal state from the old SID.
2263          * If not, clear itimers to avoid subsequent signal generation and
2264          * flush and unblock signals.
2265          *
2266          * This must occur _after_ the task SID has been updated so that any
2267          * kill done after the flush will be checked against the new SID.
2268          */
2269         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2270         if (rc) {
2271                 memset(&itimer, 0, sizeof itimer);
2272                 for (i = 0; i < 3; i++)
2273                         do_setitimer(i, &itimer, NULL);
2274                 spin_lock_irq(&current->sighand->siglock);
2275                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2276                         __flush_signals(current);
2277                         flush_signal_handlers(current, 1);
2278                         sigemptyset(&current->blocked);
2279                 }
2280                 spin_unlock_irq(&current->sighand->siglock);
2281         }
2282
2283         /* Wake up the parent if it is waiting so that it can recheck
2284          * wait permission to the new task SID. */
2285         read_lock(&tasklist_lock);
2286         __wake_up_parent(current, current->real_parent);
2287         read_unlock(&tasklist_lock);
2288 }
2289
2290 /* superblock security operations */
2291
2292 static int selinux_sb_alloc_security(struct super_block *sb)
2293 {
2294         return superblock_alloc_security(sb);
2295 }
2296
2297 static void selinux_sb_free_security(struct super_block *sb)
2298 {
2299         superblock_free_security(sb);
2300 }
2301
2302 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2303 {
2304         if (plen > olen)
2305                 return 0;
2306
2307         return !memcmp(prefix, option, plen);
2308 }
2309
2310 static inline int selinux_option(char *option, int len)
2311 {
2312         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2313                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2314                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2315                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2316                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2317 }
2318
2319 static inline void take_option(char **to, char *from, int *first, int len)
2320 {
2321         if (!*first) {
2322                 **to = ',';
2323                 *to += 1;
2324         } else
2325                 *first = 0;
2326         memcpy(*to, from, len);
2327         *to += len;
2328 }
2329
2330 static inline void take_selinux_option(char **to, char *from, int *first,
2331                                        int len)
2332 {
2333         int current_size = 0;
2334
2335         if (!*first) {
2336                 **to = '|';
2337                 *to += 1;
2338         } else
2339                 *first = 0;
2340
2341         while (current_size < len) {
2342                 if (*from != '"') {
2343                         **to = *from;
2344                         *to += 1;
2345                 }
2346                 from += 1;
2347                 current_size += 1;
2348         }
2349 }
2350
2351 static int selinux_sb_copy_data(char *orig, char *copy)
2352 {
2353         int fnosec, fsec, rc = 0;
2354         char *in_save, *in_curr, *in_end;
2355         char *sec_curr, *nosec_save, *nosec;
2356         int open_quote = 0;
2357
2358         in_curr = orig;
2359         sec_curr = copy;
2360
2361         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2362         if (!nosec) {
2363                 rc = -ENOMEM;
2364                 goto out;
2365         }
2366
2367         nosec_save = nosec;
2368         fnosec = fsec = 1;
2369         in_save = in_end = orig;
2370
2371         do {
2372                 if (*in_end == '"')
2373                         open_quote = !open_quote;
2374                 if ((*in_end == ',' && open_quote == 0) ||
2375                                 *in_end == '\0') {
2376                         int len = in_end - in_curr;
2377
2378                         if (selinux_option(in_curr, len))
2379                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2380                         else
2381                                 take_option(&nosec, in_curr, &fnosec, len);
2382
2383                         in_curr = in_end + 1;
2384                 }
2385         } while (*in_end++);
2386
2387         strcpy(in_save, nosec_save);
2388         free_page((unsigned long)nosec_save);
2389 out:
2390         return rc;
2391 }
2392
2393 static int selinux_sb_remount(struct super_block *sb, void *data)
2394 {
2395         int rc, i, *flags;
2396         struct security_mnt_opts opts;
2397         char *secdata, **mount_options;
2398         struct superblock_security_struct *sbsec = sb->s_security;
2399
2400         if (!(sbsec->flags & SE_SBINITIALIZED))
2401                 return 0;
2402
2403         if (!data)
2404                 return 0;
2405
2406         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2407                 return 0;
2408
2409         security_init_mnt_opts(&opts);
2410         secdata = alloc_secdata();
2411         if (!secdata)
2412                 return -ENOMEM;
2413         rc = selinux_sb_copy_data(data, secdata);
2414         if (rc)
2415                 goto out_free_secdata;
2416
2417         rc = selinux_parse_opts_str(secdata, &opts);
2418         if (rc)
2419                 goto out_free_secdata;
2420
2421         mount_options = opts.mnt_opts;
2422         flags = opts.mnt_opts_flags;
2423
2424         for (i = 0; i < opts.num_mnt_opts; i++) {
2425                 u32 sid;
2426                 size_t len;
2427
2428                 if (flags[i] == SE_SBLABELSUPP)
2429                         continue;
2430                 len = strlen(mount_options[i]);
2431                 rc = security_context_to_sid(mount_options[i], len, &sid);
2432                 if (rc) {
2433                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2434                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2435                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2436                         goto out_free_opts;
2437                 }
2438                 rc = -EINVAL;
2439                 switch (flags[i]) {
2440                 case FSCONTEXT_MNT:
2441                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2442                                 goto out_bad_option;
2443                         break;
2444                 case CONTEXT_MNT:
2445                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2446                                 goto out_bad_option;
2447                         break;
2448                 case ROOTCONTEXT_MNT: {
2449                         struct inode_security_struct *root_isec;
2450                         root_isec = sb->s_root->d_inode->i_security;
2451
2452                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2453                                 goto out_bad_option;
2454                         break;
2455                 }
2456                 case DEFCONTEXT_MNT:
2457                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2458                                 goto out_bad_option;
2459                         break;
2460                 default:
2461                         goto out_free_opts;
2462                 }
2463         }
2464
2465         rc = 0;
2466 out_free_opts:
2467         security_free_mnt_opts(&opts);
2468 out_free_secdata:
2469         free_secdata(secdata);
2470         return rc;
2471 out_bad_option:
2472         printk(KERN_WARNING "SELinux: unable to change security options "
2473                "during remount (dev %s, type=%s)\n", sb->s_id,
2474                sb->s_type->name);
2475         goto out_free_opts;
2476 }
2477
2478 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2479 {
2480         const struct cred *cred = current_cred();
2481         struct common_audit_data ad;
2482         int rc;
2483
2484         rc = superblock_doinit(sb, data);
2485         if (rc)
2486                 return rc;
2487
2488         /* Allow all mounts performed by the kernel */
2489         if (flags & MS_KERNMOUNT)
2490                 return 0;
2491
2492         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2493         ad.u.dentry = sb->s_root;
2494         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2495 }
2496
2497 static int selinux_sb_statfs(struct dentry *dentry)
2498 {
2499         const struct cred *cred = current_cred();
2500         struct common_audit_data ad;
2501
2502         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2503         ad.u.dentry = dentry->d_sb->s_root;
2504         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2505 }
2506
2507 static int selinux_mount(char *dev_name,
2508                          struct path *path,
2509                          char *type,
2510                          unsigned long flags,
2511                          void *data)
2512 {
2513         const struct cred *cred = current_cred();
2514
2515         if (flags & MS_REMOUNT)
2516                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2517                                            FILESYSTEM__REMOUNT, NULL);
2518         else
2519                 return path_has_perm(cred, path, FILE__MOUNTON);
2520 }
2521
2522 static int selinux_umount(struct vfsmount *mnt, int flags)
2523 {
2524         const struct cred *cred = current_cred();
2525
2526         return superblock_has_perm(cred, mnt->mnt_sb,
2527                                    FILESYSTEM__UNMOUNT, NULL);
2528 }
2529
2530 /* inode security operations */
2531
2532 static int selinux_inode_alloc_security(struct inode *inode)
2533 {
2534         return inode_alloc_security(inode);
2535 }
2536
2537 static void selinux_inode_free_security(struct inode *inode)
2538 {
2539         inode_free_security(inode);
2540 }
2541
2542 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2543                                        const struct qstr *qstr, char **name,
2544                                        void **value, size_t *len)
2545 {
2546         const struct task_security_struct *tsec = current_security();
2547         struct inode_security_struct *dsec;
2548         struct superblock_security_struct *sbsec;
2549         u32 sid, newsid, clen;
2550         int rc;
2551         char *namep = NULL, *context;
2552
2553         dsec = dir->i_security;
2554         sbsec = dir->i_sb->s_security;
2555
2556         sid = tsec->sid;
2557         newsid = tsec->create_sid;
2558
2559         if ((sbsec->flags & SE_SBINITIALIZED) &&
2560             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2561                 newsid = sbsec->mntpoint_sid;
2562         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2563                 rc = security_transition_sid(sid, dsec->sid,
2564                                              inode_mode_to_security_class(inode->i_mode),
2565                                              qstr, &newsid);
2566                 if (rc) {
2567                         printk(KERN_WARNING "%s:  "
2568                                "security_transition_sid failed, rc=%d (dev=%s "
2569                                "ino=%ld)\n",
2570                                __func__,
2571                                -rc, inode->i_sb->s_id, inode->i_ino);
2572                         return rc;
2573                 }
2574         }
2575
2576         /* Possibly defer initialization to selinux_complete_init. */
2577         if (sbsec->flags & SE_SBINITIALIZED) {
2578                 struct inode_security_struct *isec = inode->i_security;
2579                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2580                 isec->sid = newsid;
2581                 isec->initialized = 1;
2582         }
2583
2584         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2585                 return -EOPNOTSUPP;
2586
2587         if (name) {
2588                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2589                 if (!namep)
2590                         return -ENOMEM;
2591                 *name = namep;
2592         }
2593
2594         if (value && len) {
2595                 rc = security_sid_to_context_force(newsid, &context, &clen);
2596                 if (rc) {
2597                         kfree(namep);
2598                         return rc;
2599                 }
2600                 *value = context;
2601                 *len = clen;
2602         }
2603
2604         return 0;
2605 }
2606
2607 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2608 {
2609         return may_create(dir, dentry, SECCLASS_FILE);
2610 }
2611
2612 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2613 {
2614         return may_link(dir, old_dentry, MAY_LINK);
2615 }
2616
2617 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2618 {
2619         return may_link(dir, dentry, MAY_UNLINK);
2620 }
2621
2622 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2623 {
2624         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2625 }
2626
2627 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2628 {
2629         return may_create(dir, dentry, SECCLASS_DIR);
2630 }
2631
2632 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2633 {
2634         return may_link(dir, dentry, MAY_RMDIR);
2635 }
2636
2637 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2638 {
2639         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2640 }
2641
2642 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2643                                 struct inode *new_inode, struct dentry *new_dentry)
2644 {
2645         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2646 }
2647
2648 static int selinux_inode_readlink(struct dentry *dentry)
2649 {
2650         const struct cred *cred = current_cred();
2651
2652         return dentry_has_perm(cred, dentry, FILE__READ);
2653 }
2654
2655 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2656 {
2657         const struct cred *cred = current_cred();
2658
2659         return dentry_has_perm(cred, dentry, FILE__READ);
2660 }
2661
2662 static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags)
2663 {
2664         const struct cred *cred = current_cred();
2665         struct common_audit_data ad;
2666         u32 perms;
2667         bool from_access;
2668
2669         from_access = mask & MAY_ACCESS;
2670         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2671
2672         /* No permission to check.  Existence test. */
2673         if (!mask)
2674                 return 0;
2675
2676         COMMON_AUDIT_DATA_INIT(&ad, INODE);
2677         ad.u.inode = inode;
2678
2679         if (from_access)
2680                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2681
2682         perms = file_mask_to_av(inode->i_mode, mask);
2683
2684         return inode_has_perm(cred, inode, perms, &ad, flags);
2685 }
2686
2687 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2688 {
2689         const struct cred *cred = current_cred();
2690         unsigned int ia_valid = iattr->ia_valid;
2691
2692         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2693         if (ia_valid & ATTR_FORCE) {
2694                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2695                               ATTR_FORCE);
2696                 if (!ia_valid)
2697                         return 0;
2698         }
2699
2700         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2701                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2702                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2703
2704         return dentry_has_perm(cred, dentry, FILE__WRITE);
2705 }
2706
2707 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2708 {
2709         const struct cred *cred = current_cred();
2710         struct path path;
2711
2712         path.dentry = dentry;
2713         path.mnt = mnt;
2714
2715         return path_has_perm(cred, &path, FILE__GETATTR);
2716 }
2717
2718 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2719 {
2720         const struct cred *cred = current_cred();
2721
2722         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2723                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2724                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2725                         if (!capable(CAP_SETFCAP))
2726                                 return -EPERM;
2727                 } else if (!capable(CAP_SYS_ADMIN)) {
2728                         /* A different attribute in the security namespace.
2729                            Restrict to administrator. */
2730                         return -EPERM;
2731                 }
2732         }
2733
2734         /* Not an attribute we recognize, so just check the
2735            ordinary setattr permission. */
2736         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2737 }
2738
2739 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2740                                   const void *value, size_t size, int flags)
2741 {
2742         struct inode *inode = dentry->d_inode;
2743         struct inode_security_struct *isec = inode->i_security;
2744         struct superblock_security_struct *sbsec;
2745         struct common_audit_data ad;
2746         u32 newsid, sid = current_sid();
2747         int rc = 0;
2748
2749         if (strcmp(name, XATTR_NAME_SELINUX))
2750                 return selinux_inode_setotherxattr(dentry, name);
2751
2752         sbsec = inode->i_sb->s_security;
2753         if (!(sbsec->flags & SE_SBLABELSUPP))
2754                 return -EOPNOTSUPP;
2755
2756         if (!inode_owner_or_capable(inode))
2757                 return -EPERM;
2758
2759         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2760         ad.u.dentry = dentry;
2761
2762         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2763                           FILE__RELABELFROM, &ad);
2764         if (rc)
2765                 return rc;
2766
2767         rc = security_context_to_sid(value, size, &newsid);
2768         if (rc == -EINVAL) {
2769                 if (!capable(CAP_MAC_ADMIN))
2770                         return rc;
2771                 rc = security_context_to_sid_force(value, size, &newsid);
2772         }
2773         if (rc)
2774                 return rc;
2775
2776         rc = avc_has_perm(sid, newsid, isec->sclass,
2777                           FILE__RELABELTO, &ad);
2778         if (rc)
2779                 return rc;
2780
2781         rc = security_validate_transition(isec->sid, newsid, sid,
2782                                           isec->sclass);
2783         if (rc)
2784                 return rc;
2785
2786         return avc_has_perm(newsid,
2787                             sbsec->sid,
2788                             SECCLASS_FILESYSTEM,
2789                             FILESYSTEM__ASSOCIATE,
2790                             &ad);
2791 }
2792
2793 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2794                                         const void *value, size_t size,
2795                                         int flags)
2796 {
2797         struct inode *inode = dentry->d_inode;
2798         struct inode_security_struct *isec = inode->i_security;
2799         u32 newsid;
2800         int rc;
2801
2802         if (strcmp(name, XATTR_NAME_SELINUX)) {
2803                 /* Not an attribute we recognize, so nothing to do. */
2804                 return;
2805         }
2806
2807         rc = security_context_to_sid_force(value, size, &newsid);
2808         if (rc) {
2809                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2810                        "for (%s, %lu), rc=%d\n",
2811                        inode->i_sb->s_id, inode->i_ino, -rc);
2812                 return;
2813         }
2814
2815         isec->sid = newsid;
2816         return;
2817 }
2818
2819 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2820 {
2821         const struct cred *cred = current_cred();
2822
2823         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2824 }
2825
2826 static int selinux_inode_listxattr(struct dentry *dentry)
2827 {
2828         const struct cred *cred = current_cred();
2829
2830         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2831 }
2832
2833 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2834 {
2835         if (strcmp(name, XATTR_NAME_SELINUX))
2836                 return selinux_inode_setotherxattr(dentry, name);
2837
2838         /* No one is allowed to remove a SELinux security label.
2839            You can change the label, but all data must be labeled. */
2840         return -EACCES;
2841 }
2842
2843 /*
2844  * Copy the inode security context value to the user.
2845  *
2846  * Permission check is handled by selinux_inode_getxattr hook.
2847  */
2848 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2849 {
2850         u32 size;
2851         int error;
2852         char *context = NULL;
2853         struct inode_security_struct *isec = inode->i_security;
2854
2855         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2856                 return -EOPNOTSUPP;
2857
2858         /*
2859          * If the caller has CAP_MAC_ADMIN, then get the raw context
2860          * value even if it is not defined by current policy; otherwise,
2861          * use the in-core value under current policy.
2862          * Use the non-auditing forms of the permission checks since
2863          * getxattr may be called by unprivileged processes commonly
2864          * and lack of permission just means that we fall back to the
2865          * in-core context value, not a denial.
2866          */
2867         error = selinux_capable(current, current_cred(),
2868                                 &init_user_ns, CAP_MAC_ADMIN,
2869                                 SECURITY_CAP_NOAUDIT);
2870         if (!error)
2871                 error = security_sid_to_context_force(isec->sid, &context,
2872                                                       &size);
2873         else
2874                 error = security_sid_to_context(isec->sid, &context, &size);
2875         if (error)
2876                 return error;
2877         error = size;
2878         if (alloc) {
2879                 *buffer = context;
2880                 goto out_nofree;
2881         }
2882         kfree(context);
2883 out_nofree:
2884         return error;
2885 }
2886
2887 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2888                                      const void *value, size_t size, int flags)
2889 {
2890         struct inode_security_struct *isec = inode->i_security;
2891         u32 newsid;
2892         int rc;
2893
2894         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2895                 return -EOPNOTSUPP;
2896
2897         if (!value || !size)
2898                 return -EACCES;
2899
2900         rc = security_context_to_sid((void *)value, size, &newsid);
2901         if (rc)
2902                 return rc;
2903
2904         isec->sid = newsid;
2905         isec->initialized = 1;
2906         return 0;
2907 }
2908
2909 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2910 {
2911         const int len = sizeof(XATTR_NAME_SELINUX);
2912         if (buffer && len <= buffer_size)
2913                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2914         return len;
2915 }
2916
2917 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2918 {
2919         struct inode_security_struct *isec = inode->i_security;
2920         *secid = isec->sid;
2921 }
2922
2923 /* file security operations */
2924
2925 static int selinux_revalidate_file_permission(struct file *file, int mask)
2926 {
2927         const struct cred *cred = current_cred();
2928         struct inode *inode = file->f_path.dentry->d_inode;
2929
2930         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2931         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2932                 mask |= MAY_APPEND;
2933
2934         return file_has_perm(cred, file,
2935                              file_mask_to_av(inode->i_mode, mask));
2936 }
2937
2938 static int selinux_file_permission(struct file *file, int mask)
2939 {
2940         struct inode *inode = file->f_path.dentry->d_inode;
2941         struct file_security_struct *fsec = file->f_security;
2942         struct inode_security_struct *isec = inode->i_security;
2943         u32 sid = current_sid();
2944
2945         if (!mask)
2946                 /* No permission to check.  Existence test. */
2947                 return 0;
2948
2949         if (sid == fsec->sid && fsec->isid == isec->sid &&
2950             fsec->pseqno == avc_policy_seqno())
2951                 /* No change since dentry_open check. */
2952                 return 0;
2953
2954         return selinux_revalidate_file_permission(file, mask);
2955 }
2956
2957 static int selinux_file_alloc_security(struct file *file)
2958 {
2959         return file_alloc_security(file);
2960 }
2961
2962 static void selinux_file_free_security(struct file *file)
2963 {
2964         file_free_security(file);
2965 }
2966
2967 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2968                               unsigned long arg)
2969 {
2970         const struct cred *cred = current_cred();
2971         int error = 0;
2972
2973         switch (cmd) {
2974         case FIONREAD:
2975         /* fall through */
2976         case FIBMAP:
2977         /* fall through */
2978         case FIGETBSZ:
2979         /* fall through */
2980         case EXT2_IOC_GETFLAGS:
2981         /* fall through */
2982         case EXT2_IOC_GETVERSION:
2983                 error = file_has_perm(cred, file, FILE__GETATTR);
2984                 break;
2985
2986         case EXT2_IOC_SETFLAGS:
2987         /* fall through */
2988         case EXT2_IOC_SETVERSION:
2989                 error = file_has_perm(cred, file, FILE__SETATTR);
2990                 break;
2991
2992         /* sys_ioctl() checks */
2993         case FIONBIO:
2994         /* fall through */
2995         case FIOASYNC:
2996                 error = file_has_perm(cred, file, 0);
2997                 break;
2998
2999         case KDSKBENT:
3000         case KDSKBSENT:
3001                 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
3002                                         SECURITY_CAP_AUDIT);
3003                 break;
3004
3005         /* default case assumes that the command will go
3006          * to the file's ioctl() function.
3007          */
3008         default:
3009                 error = file_has_perm(cred, file, FILE__IOCTL);
3010         }
3011         return error;
3012 }
3013
3014 static int default_noexec;
3015
3016 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3017 {
3018         const struct cred *cred = current_cred();
3019         int rc = 0;
3020
3021         if (default_noexec &&
3022             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3023                 /*
3024                  * We are making executable an anonymous mapping or a
3025                  * private file mapping that will also be writable.
3026                  * This has an additional check.
3027                  */
3028                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3029                 if (rc)
3030                         goto error;
3031         }
3032
3033         if (file) {
3034                 /* read access is always possible with a mapping */
3035                 u32 av = FILE__READ;
3036
3037                 /* write access only matters if the mapping is shared */
3038                 if (shared && (prot & PROT_WRITE))
3039                         av |= FILE__WRITE;
3040
3041                 if (prot & PROT_EXEC)
3042                         av |= FILE__EXECUTE;
3043
3044                 return file_has_perm(cred, file, av);
3045         }
3046
3047 error:
3048         return rc;
3049 }
3050
3051 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3052                              unsigned long prot, unsigned long flags,
3053                              unsigned long addr, unsigned long addr_only)
3054 {
3055         int rc = 0;
3056         u32 sid = current_sid();
3057
3058         /*
3059          * notice that we are intentionally putting the SELinux check before
3060          * the secondary cap_file_mmap check.  This is such a likely attempt
3061          * at bad behaviour/exploit that we always want to get the AVC, even
3062          * if DAC would have also denied the operation.
3063          */
3064         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3065                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3066                                   MEMPROTECT__MMAP_ZERO, NULL);
3067                 if (rc)
3068                         return rc;
3069         }
3070
3071         /* do DAC check on address space usage */
3072         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3073         if (rc || addr_only)
3074                 return rc;
3075
3076         if (selinux_checkreqprot)
3077                 prot = reqprot;
3078
3079         return file_map_prot_check(file, prot,
3080                                    (flags & MAP_TYPE) == MAP_SHARED);
3081 }
3082
3083 static int selinux_file_mprotect(struct vm_area_struct *vma,
3084                                  unsigned long reqprot,
3085                                  unsigned long prot)
3086 {
3087         const struct cred *cred = current_cred();
3088
3089         if (selinux_checkreqprot)
3090                 prot = reqprot;
3091
3092         if (default_noexec &&
3093             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3094                 int rc = 0;
3095                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3096                     vma->vm_end <= vma->vm_mm->brk) {
3097                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3098                 } else if (!vma->vm_file &&
3099                            vma->vm_start <= vma->vm_mm->start_stack &&
3100                            vma->vm_end >= vma->vm_mm->start_stack) {
3101                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3102                 } else if (vma->vm_file && vma->anon_vma) {
3103                         /*
3104                          * We are making executable a file mapping that has
3105                          * had some COW done. Since pages might have been
3106                          * written, check ability to execute the possibly
3107                          * modified content.  This typically should only
3108                          * occur for text relocations.
3109                          */
3110                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3111                 }
3112                 if (rc)
3113                         return rc;
3114         }
3115
3116         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3117 }
3118
3119 static int selinux_file_lock(struct file *file, unsigned int cmd)
3120 {
3121         const struct cred *cred = current_cred();
3122
3123         return file_has_perm(cred, file, FILE__LOCK);
3124 }
3125
3126 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3127                               unsigned long arg)
3128 {
3129         const struct cred *cred = current_cred();
3130         int err = 0;
3131
3132         switch (cmd) {
3133         case F_SETFL:
3134                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3135                         err = -EINVAL;
3136                         break;
3137                 }
3138
3139                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3140                         err = file_has_perm(cred, file, FILE__WRITE);
3141                         break;
3142                 }
3143                 /* fall through */
3144         case F_SETOWN:
3145         case F_SETSIG:
3146         case F_GETFL:
3147         case F_GETOWN:
3148         case F_GETSIG:
3149                 /* Just check FD__USE permission */
3150                 err = file_has_perm(cred, file, 0);
3151                 break;
3152         case F_GETLK:
3153         case F_SETLK:
3154         case F_SETLKW:
3155 #if BITS_PER_LONG == 32
3156         case F_GETLK64:
3157         case F_SETLK64:
3158         case F_SETLKW64:
3159 #endif
3160                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3161                         err = -EINVAL;
3162                         break;
3163                 }
3164                 err = file_has_perm(cred, file, FILE__LOCK);
3165                 break;
3166         }
3167
3168         return err;
3169 }
3170
3171 static int selinux_file_set_fowner(struct file *file)
3172 {
3173         struct file_security_struct *fsec;
3174
3175         fsec = file->f_security;
3176         fsec->fown_sid = current_sid();
3177
3178         return 0;
3179 }
3180
3181 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3182                                        struct fown_struct *fown, int signum)
3183 {
3184         struct file *file;
3185         u32 sid = task_sid(tsk);
3186         u32 perm;
3187         struct file_security_struct *fsec;
3188
3189         /* struct fown_struct is never outside the context of a struct file */
3190         file = container_of(fown, struct file, f_owner);
3191
3192         fsec = file->f_security;
3193
3194         if (!signum)
3195                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3196         else
3197                 perm = signal_to_av(signum);
3198
3199         return avc_has_perm(fsec->fown_sid, sid,
3200                             SECCLASS_PROCESS, perm, NULL);
3201 }
3202
3203 static int selinux_file_receive(struct file *file)
3204 {
3205         const struct cred *cred = current_cred();
3206
3207         return file_has_perm(cred, file, file_to_av(file));
3208 }
3209
3210 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3211 {
3212         struct file_security_struct *fsec;
3213         struct inode *inode;
3214         struct inode_security_struct *isec;
3215
3216         inode = file->f_path.dentry->d_inode;
3217         fsec = file->f_security;
3218         isec = inode->i_security;
3219         /*
3220          * Save inode label and policy sequence number
3221          * at open-time so that selinux_file_permission
3222          * can determine whether revalidation is necessary.
3223          * Task label is already saved in the file security
3224          * struct as its SID.
3225          */
3226         fsec->isid = isec->sid;
3227         fsec->pseqno = avc_policy_seqno();
3228         /*
3229          * Since the inode label or policy seqno may have changed
3230          * between the selinux_inode_permission check and the saving
3231          * of state above, recheck that access is still permitted.
3232          * Otherwise, access might never be revalidated against the
3233          * new inode label or new policy.
3234          * This check is not redundant - do not remove.
3235          */
3236         return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3237 }
3238
3239 /* task security operations */
3240
3241 static int selinux_task_create(unsigned long clone_flags)
3242 {
3243         return current_has_perm(current, PROCESS__FORK);
3244 }
3245
3246 /*
3247  * allocate the SELinux part of blank credentials
3248  */
3249 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3250 {
3251         struct task_security_struct *tsec;
3252
3253         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3254         if (!tsec)
3255                 return -ENOMEM;
3256
3257         cred->security = tsec;
3258         return 0;
3259 }
3260
3261 /*
3262  * detach and free the LSM part of a set of credentials
3263  */
3264 static void selinux_cred_free(struct cred *cred)
3265 {
3266         struct task_security_struct *tsec = cred->security;
3267
3268         /*
3269          * cred->security == NULL if security_cred_alloc_blank() or
3270          * security_prepare_creds() returned an error.
3271          */
3272         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3273         cred->security = (void *) 0x7UL;
3274         kfree(tsec);
3275 }
3276
3277 /*
3278  * prepare a new set of credentials for modification
3279  */
3280 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3281                                 gfp_t gfp)
3282 {
3283         const struct task_security_struct *old_tsec;
3284         struct task_security_struct *tsec;
3285
3286         old_tsec = old->security;
3287
3288         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3289         if (!tsec)
3290                 return -ENOMEM;
3291
3292         new->security = tsec;
3293         return 0;
3294 }
3295
3296 /*
3297  * transfer the SELinux data to a blank set of creds
3298  */
3299 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3300 {
3301         const struct task_security_struct *old_tsec = old->security;
3302         struct task_security_struct *tsec = new->security;
3303
3304         *tsec = *old_tsec;
3305 }
3306
3307 /*
3308  * set the security data for a kernel service
3309  * - all the creation contexts are set to unlabelled
3310  */
3311 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3312 {
3313         struct task_security_struct *tsec = new->security;
3314         u32 sid = current_sid();
3315         int ret;
3316
3317         ret = avc_has_perm(sid, secid,
3318                            SECCLASS_KERNEL_SERVICE,
3319                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3320                            NULL);
3321         if (ret == 0) {
3322                 tsec->sid = secid;
3323                 tsec->create_sid = 0;
3324                 tsec->keycreate_sid = 0;
3325                 tsec->sockcreate_sid = 0;
3326         }
3327         return ret;
3328 }
3329
3330 /*
3331  * set the file creation context in a security record to the same as the
3332  * objective context of the specified inode
3333  */
3334 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3335 {
3336         struct inode_security_struct *isec = inode->i_security;
3337         struct task_security_struct *tsec = new->security;
3338         u32 sid = current_sid();
3339         int ret;
3340
3341         ret = avc_has_perm(sid, isec->sid,
3342                            SECCLASS_KERNEL_SERVICE,
3343                            KERNEL_SERVICE__CREATE_FILES_AS,
3344                            NULL);
3345
3346         if (ret == 0)
3347                 tsec->create_sid = isec->sid;
3348         return ret;
3349 }
3350
3351 static int selinux_kernel_module_request(char *kmod_name)
3352 {
3353         u32 sid;
3354         struct common_audit_data ad;
3355
3356         sid = task_sid(current);
3357
3358         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3359         ad.u.kmod_name = kmod_name;
3360
3361         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3362                             SYSTEM__MODULE_REQUEST, &ad);
3363 }
3364
3365 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3366 {
3367         return current_has_perm(p, PROCESS__SETPGID);
3368 }
3369
3370 static int selinux_task_getpgid(struct task_struct *p)
3371 {
3372         return current_has_perm(p, PROCESS__GETPGID);
3373 }
3374
3375 static int selinux_task_getsid(struct task_struct *p)
3376 {
3377         return current_has_perm(p, PROCESS__GETSESSION);
3378 }
3379
3380 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3381 {
3382         *secid = task_sid(p);
3383 }
3384
3385 static int selinux_task_setnice(struct task_struct *p, int nice)
3386 {
3387         int rc;
3388
3389         rc = cap_task_setnice(p, nice);
3390         if (rc)
3391                 return rc;
3392
3393         return current_has_perm(p, PROCESS__SETSCHED);
3394 }
3395
3396 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3397 {
3398         int rc;
3399
3400         rc = cap_task_setioprio(p, ioprio);
3401         if (rc)
3402                 return rc;
3403
3404         return current_has_perm(p, PROCESS__SETSCHED);
3405 }
3406
3407 static int selinux_task_getioprio(struct task_struct *p)
3408 {
3409         return current_has_perm(p, PROCESS__GETSCHED);
3410 }
3411
3412 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3413                 struct rlimit *new_rlim)
3414 {
3415         struct rlimit *old_rlim = p->signal->rlim + resource;
3416
3417         /* Control the ability to change the hard limit (whether
3418            lowering or raising it), so that the hard limit can
3419            later be used as a safe reset point for the soft limit
3420            upon context transitions.  See selinux_bprm_committing_creds. */
3421         if (old_rlim->rlim_max != new_rlim->rlim_max)
3422                 return current_has_perm(p, PROCESS__SETRLIMIT);
3423
3424         return 0;
3425 }
3426
3427 static int selinux_task_setscheduler(struct task_struct *p)
3428 {
3429         int rc;
3430
3431         rc = cap_task_setscheduler(p);
3432         if (rc)
3433                 return rc;
3434
3435         return current_has_perm(p, PROCESS__SETSCHED);
3436 }
3437
3438 static int selinux_task_getscheduler(struct task_struct *p)
3439 {
3440         return current_has_perm(p, PROCESS__GETSCHED);
3441 }
3442
3443 static int selinux_task_movememory(struct task_struct *p)
3444 {
3445         return current_has_perm(p, PROCESS__SETSCHED);
3446 }
3447
3448 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3449                                 int sig, u32 secid)
3450 {
3451         u32 perm;
3452         int rc;
3453
3454         if (!sig)
3455                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3456         else
3457                 perm = signal_to_av(sig);
3458         if (secid)
3459                 rc = avc_has_perm(secid, task_sid(p),
3460                                   SECCLASS_PROCESS, perm, NULL);
3461         else
3462                 rc = current_has_perm(p, perm);
3463         return rc;
3464 }
3465
3466 static int selinux_task_wait(struct task_struct *p)
3467 {
3468         return task_has_perm(p, current, PROCESS__SIGCHLD);
3469 }
3470
3471 static void selinux_task_to_inode(struct task_struct *p,
3472                                   struct inode *inode)
3473 {
3474         struct inode_security_struct *isec = inode->i_security;
3475         u32 sid = task_sid(p);
3476
3477         isec->sid = sid;
3478         isec->initialized = 1;
3479 }
3480
3481 /* Returns error only if unable to parse addresses */
3482 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3483                         struct common_audit_data *ad, u8 *proto)
3484 {
3485         int offset, ihlen, ret = -EINVAL;
3486         struct iphdr _iph, *ih;
3487
3488         offset = skb_network_offset(skb);
3489         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3490         if (ih == NULL)
3491                 goto out;
3492
3493         ihlen = ih->ihl * 4;
3494         if (ihlen < sizeof(_iph))
3495                 goto out;
3496
3497         ad->u.net.v4info.saddr = ih->saddr;
3498         ad->u.net.v4info.daddr = ih->daddr;
3499         ret = 0;
3500
3501         if (proto)
3502                 *proto = ih->protocol;
3503
3504         switch (ih->protocol) {
3505         case IPPROTO_TCP: {
3506                 struct tcphdr _tcph, *th;
3507
3508                 if (ntohs(ih->frag_off) & IP_OFFSET)
3509                         break;
3510
3511                 offset += ihlen;
3512                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3513                 if (th == NULL)
3514                         break;
3515
3516                 ad->u.net.sport = th->source;
3517                 ad->u.net.dport = th->dest;
3518                 break;
3519         }
3520
3521         case IPPROTO_UDP: {
3522                 struct udphdr _udph, *uh;
3523
3524                 if (ntohs(ih->frag_off) & IP_OFFSET)
3525                         break;
3526
3527                 offset += ihlen;
3528                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3529                 if (uh == NULL)
3530                         break;
3531
3532                 ad->u.net.sport = uh->source;
3533                 ad->u.net.dport = uh->dest;
3534                 break;
3535         }
3536
3537         case IPPROTO_DCCP: {
3538                 struct dccp_hdr _dccph, *dh;
3539
3540                 if (ntohs(ih->frag_off) & IP_OFFSET)
3541                         break;
3542
3543                 offset += ihlen;
3544                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3545                 if (dh == NULL)
3546                         break;
3547
3548                 ad->u.net.sport = dh->dccph_sport;
3549                 ad->u.net.dport = dh->dccph_dport;
3550                 break;
3551         }
3552
3553         default:
3554                 break;
3555         }
3556 out:
3557         return ret;
3558 }
3559
3560 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3561
3562 /* Returns error only if unable to parse addresses */
3563 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3564                         struct common_audit_data *ad, u8 *proto)
3565 {
3566         u8 nexthdr;
3567         int ret = -EINVAL, offset;
3568         struct ipv6hdr _ipv6h, *ip6;
3569
3570         offset = skb_network_offset(skb);
3571         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3572         if (ip6 == NULL)
3573                 goto out;
3574
3575         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3576         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3577         ret = 0;
3578
3579         nexthdr = ip6->nexthdr;
3580         offset += sizeof(_ipv6h);
3581         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3582         if (offset < 0)
3583                 goto out;
3584
3585         if (proto)
3586                 *proto = nexthdr;
3587
3588         switch (nexthdr) {
3589         case IPPROTO_TCP: {
3590                 struct tcphdr _tcph, *th;
3591
3592                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3593                 if (th == NULL)
3594                         break;
3595
3596                 ad->u.net.sport = th->source;
3597                 ad->u.net.dport = th->dest;
3598                 break;
3599         }
3600
3601         case IPPROTO_UDP: {
3602                 struct udphdr _udph, *uh;
3603
3604                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3605                 if (uh == NULL)
3606                         break;
3607
3608                 ad->u.net.sport = uh->source;
3609                 ad->u.net.dport = uh->dest;
3610                 break;
3611         }
3612
3613         case IPPROTO_DCCP: {
3614                 struct dccp_hdr _dccph, *dh;
3615
3616                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3617                 if (dh == NULL)
3618                         break;
3619
3620                 ad->u.net.sport = dh->dccph_sport;
3621                 ad->u.net.dport = dh->dccph_dport;
3622                 break;
3623         }
3624
3625         /* includes fragments */
3626         default:
3627                 break;
3628         }
3629 out:
3630         return ret;
3631 }
3632
3633 #endif /* IPV6 */
3634
3635 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3636                              char **_addrp, int src, u8 *proto)
3637 {
3638         char *addrp;
3639         int ret;
3640
3641         switch (ad->u.net.family) {
3642         case PF_INET:
3643                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3644                 if (ret)
3645                         goto parse_error;
3646                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3647                                        &ad->u.net.v4info.daddr);
3648                 goto okay;
3649
3650 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3651         case PF_INET6:
3652                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3653                 if (ret)
3654                         goto parse_error;
3655                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3656                                        &ad->u.net.v6info.daddr);
3657                 goto okay;
3658 #endif  /* IPV6 */
3659         default:
3660                 addrp = NULL;
3661                 goto okay;
3662         }
3663
3664 parse_error:
3665         printk(KERN_WARNING
3666                "SELinux: failure in selinux_parse_skb(),"
3667                " unable to parse packet\n");
3668         return ret;
3669
3670 okay:
3671         if (_addrp)
3672                 *_addrp = addrp;
3673         return 0;
3674 }
3675
3676 /**
3677  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3678  * @skb: the packet
3679  * @family: protocol family
3680  * @sid: the packet's peer label SID
3681  *
3682  * Description:
3683  * Check the various different forms of network peer labeling and determine
3684  * the peer label/SID for the packet; most of the magic actually occurs in
3685  * the security server function security_net_peersid_cmp().  The function
3686  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3687  * or -EACCES if @sid is invalid due to inconsistencies with the different
3688  * peer labels.
3689  *
3690  */
3691 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3692 {
3693         int err;
3694         u32 xfrm_sid;
3695         u32 nlbl_sid;
3696         u32 nlbl_type;
3697
3698         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3699         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3700
3701         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3702         if (unlikely(err)) {
3703                 printk(KERN_WARNING
3704                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3705                        " unable to determine packet's peer label\n");
3706                 return -EACCES;
3707         }
3708
3709         return 0;
3710 }
3711
3712 /* socket security operations */
3713
3714 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3715                                  u16 secclass, u32 *socksid)
3716 {
3717         if (tsec->sockcreate_sid > SECSID_NULL) {
3718                 *socksid = tsec->sockcreate_sid;
3719                 return 0;
3720         }
3721
3722         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3723                                        socksid);
3724 }
3725
3726 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3727 {
3728         struct sk_security_struct *sksec = sk->sk_security;
3729         struct common_audit_data ad;
3730         u32 tsid = task_sid(task);
3731
3732         if (sksec->sid == SECINITSID_KERNEL)
3733                 return 0;
3734
3735         COMMON_AUDIT_DATA_INIT(&ad, NET);
3736         ad.u.net.sk = sk;
3737
3738         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3739 }
3740
3741 static int selinux_socket_create(int family, int type,
3742                                  int protocol, int kern)
3743 {
3744         const struct task_security_struct *tsec = current_security();
3745         u32 newsid;
3746         u16 secclass;
3747         int rc;
3748
3749         if (kern)
3750                 return 0;
3751
3752         secclass = socket_type_to_security_class(family, type, protocol);
3753         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3754         if (rc)
3755                 return rc;
3756
3757         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3758 }
3759
3760 static int selinux_socket_post_create(struct socket *sock, int family,
3761                                       int type, int protocol, int kern)
3762 {
3763         const struct task_security_struct *tsec = current_security();
3764         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3765         struct sk_security_struct *sksec;
3766         int err = 0;
3767
3768         isec->sclass = socket_type_to_security_class(family, type, protocol);
3769
3770         if (kern)
3771                 isec->sid = SECINITSID_KERNEL;
3772         else {
3773                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3774                 if (err)
3775                         return err;
3776         }
3777
3778         isec->initialized = 1;
3779
3780         if (sock->sk) {
3781                 sksec = sock->sk->sk_security;
3782                 sksec->sid = isec->sid;
3783                 sksec->sclass = isec->sclass;
3784                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3785         }
3786
3787         return err;
3788 }
3789
3790 /* Range of port numbers used to automatically bind.
3791    Need to determine whether we should perform a name_bind
3792    permission check between the socket and the port number. */
3793
3794 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3795 {
3796         struct sock *sk = sock->sk;
3797         u16 family;
3798         int err;
3799
3800         err = sock_has_perm(current, sk, SOCKET__BIND);
3801         if (err)
3802                 goto out;
3803
3804         /*
3805          * If PF_INET or PF_INET6, check name_bind permission for the port.
3806          * Multiple address binding for SCTP is not supported yet: we just
3807          * check the first address now.
3808          */
3809         family = sk->sk_family;
3810         if (family == PF_INET || family == PF_INET6) {
3811                 char *addrp;
3812                 struct sk_security_struct *sksec = sk->sk_security;
3813                 struct common_audit_data ad;
3814                 struct sockaddr_in *addr4 = NULL;
3815                 struct sockaddr_in6 *addr6 = NULL;
3816                 unsigned short snum;
3817                 u32 sid, node_perm;
3818
3819                 if (family == PF_INET) {
3820                         addr4 = (struct sockaddr_in *)address;
3821                         snum = ntohs(addr4->sin_port);
3822                         addrp = (char *)&addr4->sin_addr.s_addr;
3823                 } else {
3824                         addr6 = (struct sockaddr_in6 *)address;
3825                         snum = ntohs(addr6->sin6_port);
3826                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3827                 }
3828
3829                 if (snum) {
3830                         int low, high;
3831
3832                         inet_get_local_port_range(&low, &high);
3833
3834                         if (snum < max(PROT_SOCK, low) || snum > high) {
3835                                 err = sel_netport_sid(sk->sk_protocol,
3836                                                       snum, &sid);
3837                                 if (err)
3838                                         goto out;
3839                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3840                                 ad.u.net.sport = htons(snum);
3841                                 ad.u.net.family = family;
3842                                 err = avc_has_perm(sksec->sid, sid,
3843                                                    sksec->sclass,
3844                                                    SOCKET__NAME_BIND, &ad);
3845                                 if (err)
3846                                         goto out;
3847                         }
3848                 }
3849
3850                 switch (sksec->sclass) {
3851                 case SECCLASS_TCP_SOCKET:
3852                         node_perm = TCP_SOCKET__NODE_BIND;
3853                         break;
3854
3855                 case SECCLASS_UDP_SOCKET:
3856                         node_perm = UDP_SOCKET__NODE_BIND;
3857                         break;
3858
3859                 case SECCLASS_DCCP_SOCKET:
3860                         node_perm = DCCP_SOCKET__NODE_BIND;
3861                         break;
3862
3863                 default:
3864                         node_perm = RAWIP_SOCKET__NODE_BIND;
3865                         break;
3866                 }
3867
3868                 err = sel_netnode_sid(addrp, family, &sid);
3869                 if (err)
3870                         goto out;
3871
3872                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3873                 ad.u.net.sport = htons(snum);
3874                 ad.u.net.family = family;
3875
3876                 if (family == PF_INET)
3877                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3878                 else
3879                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3880
3881                 err = avc_has_perm(sksec->sid, sid,
3882                                    sksec->sclass, node_perm, &ad);
3883                 if (err)
3884                         goto out;
3885         }
3886 out:
3887         return err;
3888 }
3889
3890 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3891 {
3892         struct sock *sk = sock->sk;
3893         struct sk_security_struct *sksec = sk->sk_security;
3894         int err;
3895
3896         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3897         if (err)
3898                 return err;
3899
3900         /*
3901          * If a TCP or DCCP socket, check name_connect permission for the port.
3902          */
3903         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3904             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3905                 struct common_audit_data ad;
3906                 struct sockaddr_in *addr4 = NULL;
3907                 struct sockaddr_in6 *addr6 = NULL;
3908                 unsigned short snum;
3909                 u32 sid, perm;
3910
3911                 if (sk->sk_family == PF_INET) {
3912                         addr4 = (struct sockaddr_in *)address;
3913                         if (addrlen < sizeof(struct sockaddr_in))
3914                                 return -EINVAL;
3915                         snum = ntohs(addr4->sin_port);
3916                 } else {
3917                         addr6 = (struct sockaddr_in6 *)address;
3918                         if (addrlen < SIN6_LEN_RFC2133)
3919                                 return -EINVAL;
3920                         snum = ntohs(addr6->sin6_port);
3921                 }
3922
3923                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3924                 if (err)
3925                         goto out;
3926
3927                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3928                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3929
3930                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3931                 ad.u.net.dport = htons(snum);
3932                 ad.u.net.family = sk->sk_family;
3933                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3934                 if (err)
3935                         goto out;
3936         }
3937
3938         err = selinux_netlbl_socket_connect(sk, address);
3939
3940 out:
3941         return err;
3942 }
3943
3944 static int selinux_socket_listen(struct socket *sock, int backlog)
3945 {
3946         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3947 }
3948
3949 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3950 {
3951         int err;
3952         struct inode_security_struct *isec;
3953         struct inode_security_struct *newisec;
3954
3955         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3956         if (err)
3957                 return err;
3958
3959         newisec = SOCK_INODE(newsock)->i_security;
3960
3961         isec = SOCK_INODE(sock)->i_security;
3962         newisec->sclass = isec->sclass;
3963         newisec->sid = isec->sid;
3964         newisec->initialized = 1;
3965
3966         return 0;
3967 }
3968
3969 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3970                                   int size)
3971 {
3972         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3973 }
3974
3975 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3976                                   int size, int flags)
3977 {
3978         return sock_has_perm(current, sock->sk, SOCKET__READ);
3979 }
3980
3981 static int selinux_socket_getsockname(struct socket *sock)
3982 {
3983         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3984 }
3985
3986 static int selinux_socket_getpeername(struct socket *sock)
3987 {
3988         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3989 }
3990
3991 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3992 {
3993         int err;
3994
3995         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3996         if (err)
3997                 return err;
3998
3999         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4000 }
4001
4002 static int selinux_socket_getsockopt(struct socket *sock, int level,
4003                                      int optname)
4004 {
4005         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4006 }
4007
4008 static int selinux_socket_shutdown(struct socket *sock, int how)
4009 {
4010         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4011 }
4012
4013 static int selinux_socket_unix_stream_connect(struct sock *sock,
4014                                               struct sock *other,
4015                                               struct sock *newsk)
4016 {
4017         struct sk_security_struct *sksec_sock = sock->sk_security;
4018         struct sk_security_struct *sksec_other = other->sk_security;
4019         struct sk_security_struct *sksec_new = newsk->sk_security;
4020         struct common_audit_data ad;
4021         int err;
4022
4023         COMMON_AUDIT_DATA_INIT(&ad, NET);
4024         ad.u.net.sk = other;
4025
4026         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4027                            sksec_other->sclass,
4028                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4029         if (err)
4030                 return err;
4031
4032         /* server child socket */
4033         sksec_new->peer_sid = sksec_sock->sid;
4034         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4035                                     &sksec_new->sid);
4036         if (err)
4037                 return err;
4038
4039         /* connecting socket */
4040         sksec_sock->peer_sid = sksec_new->sid;
4041
4042         return 0;
4043 }
4044
4045 static int selinux_socket_unix_may_send(struct socket *sock,
4046                                         struct socket *other)
4047 {
4048         struct sk_security_struct *ssec = sock->sk->sk_security;
4049         struct sk_security_struct *osec = other->sk->sk_security;
4050         struct common_audit_data ad;
4051
4052         COMMON_AUDIT_DATA_INIT(&ad, NET);
4053         ad.u.net.sk = other->sk;
4054
4055         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4056                             &ad);
4057 }
4058
4059 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4060                                     u32 peer_sid,
4061                                     struct common_audit_data *ad)
4062 {
4063         int err;
4064         u32 if_sid;
4065         u32 node_sid;
4066
4067         err = sel_netif_sid(ifindex, &if_sid);
4068         if (err)
4069                 return err;
4070         err = avc_has_perm(peer_sid, if_sid,
4071                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4072         if (err)
4073                 return err;
4074
4075         err = sel_netnode_sid(addrp, family, &node_sid);
4076         if (err)
4077                 return err;
4078         return avc_has_perm(peer_sid, node_sid,
4079                             SECCLASS_NODE, NODE__RECVFROM, ad);
4080 }
4081
4082 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4083                                        u16 family)
4084 {
4085         int err = 0;
4086         struct sk_security_struct *sksec = sk->sk_security;
4087         u32 sk_sid = sksec->sid;
4088         struct common_audit_data ad;
4089         char *addrp;
4090
4091         COMMON_AUDIT_DATA_INIT(&ad, NET);
4092         ad.u.net.netif = skb->skb_iif;
4093         ad.u.net.family = family;
4094         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4095         if (err)
4096                 return err;
4097
4098         if (selinux_secmark_enabled()) {
4099                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4100                                    PACKET__RECV, &ad);
4101                 if (err)
4102                         return err;
4103         }
4104
4105         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4106         if (err)
4107                 return err;
4108         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4109
4110         return err;
4111 }
4112
4113 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4114 {
4115         int err;
4116         struct sk_security_struct *sksec = sk->sk_security;
4117         u16 family = sk->sk_family;
4118         u32 sk_sid = sksec->sid;
4119         struct common_audit_data ad;
4120         char *addrp;
4121         u8 secmark_active;
4122         u8 peerlbl_active;
4123
4124         if (family != PF_INET && family != PF_INET6)
4125                 return 0;
4126
4127         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4128         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4129                 family = PF_INET;
4130
4131         /* If any sort of compatibility mode is enabled then handoff processing
4132          * to the selinux_sock_rcv_skb_compat() function to deal with the
4133          * special handling.  We do this in an attempt to keep this function
4134          * as fast and as clean as possible. */
4135         if (!selinux_policycap_netpeer)
4136                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4137
4138         secmark_active = selinux_secmark_enabled();
4139         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4140         if (!secmark_active && !peerlbl_active)
4141                 return 0;
4142
4143         COMMON_AUDIT_DATA_INIT(&ad, NET);
4144         ad.u.net.netif = skb->skb_iif;
4145         ad.u.net.family = family;
4146         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4147         if (err)
4148                 return err;
4149
4150         if (peerlbl_active) {
4151                 u32 peer_sid;
4152
4153                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4154                 if (err)
4155                         return err;
4156                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4157                                                peer_sid, &ad);
4158                 if (err) {
4159                         selinux_netlbl_err(skb, err, 0);
4160                         return err;
4161                 }
4162                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4163                                    PEER__RECV, &ad);
4164                 if (err)
4165                         selinux_netlbl_err(skb, err, 0);
4166         }
4167
4168         if (secmark_active) {
4169                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4170                                    PACKET__RECV, &ad);
4171                 if (err)
4172                         return err;
4173         }
4174
4175         return err;
4176 }
4177
4178 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4179                                             int __user *optlen, unsigned len)
4180 {
4181         int err = 0;
4182         char *scontext;
4183         u32 scontext_len;
4184         struct sk_security_struct *sksec = sock->sk->sk_security;
4185         u32 peer_sid = SECSID_NULL;
4186
4187         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4188             sksec->sclass == SECCLASS_TCP_SOCKET)
4189                 peer_sid = sksec->peer_sid;
4190         if (peer_sid == SECSID_NULL)
4191                 return -ENOPROTOOPT;
4192
4193         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4194         if (err)
4195                 return err;
4196
4197         if (scontext_len > len) {
4198                 err = -ERANGE;
4199                 goto out_len;
4200         }
4201
4202         if (copy_to_user(optval, scontext, scontext_len))
4203                 err = -EFAULT;
4204
4205 out_len:
4206         if (put_user(scontext_len, optlen))
4207                 err = -EFAULT;
4208         kfree(scontext);
4209         return err;
4210 }
4211
4212 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4213 {
4214         u32 peer_secid = SECSID_NULL;
4215         u16 family;
4216
4217         if (skb && skb->protocol == htons(ETH_P_IP))
4218                 family = PF_INET;
4219         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4220                 family = PF_INET6;
4221         else if (sock)
4222                 family = sock->sk->sk_family;
4223         else
4224                 goto out;
4225
4226         if (sock && family == PF_UNIX)
4227                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4228         else if (skb)
4229                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4230
4231 out:
4232         *secid = peer_secid;
4233         if (peer_secid == SECSID_NULL)
4234                 return -EINVAL;
4235         return 0;
4236 }
4237
4238 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4239 {
4240         struct sk_security_struct *sksec;
4241
4242         sksec = kzalloc(sizeof(*sksec), priority);
4243         if (!sksec)
4244                 return -ENOMEM;
4245
4246         sksec->peer_sid = SECINITSID_UNLABELED;
4247         sksec->sid = SECINITSID_UNLABELED;
4248         selinux_netlbl_sk_security_reset(sksec);
4249         sk->sk_security = sksec;
4250
4251         return 0;
4252 }
4253
4254 static void selinux_sk_free_security(struct sock *sk)
4255 {
4256         struct sk_security_struct *sksec = sk->sk_security;
4257
4258         sk->sk_security = NULL;
4259         selinux_netlbl_sk_security_free(sksec);
4260         kfree(sksec);
4261 }
4262
4263 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4264 {
4265         struct sk_security_struct *sksec = sk->sk_security;
4266         struct sk_security_struct *newsksec = newsk->sk_security;
4267
4268         newsksec->sid = sksec->sid;
4269         newsksec->peer_sid = sksec->peer_sid;
4270         newsksec->sclass = sksec->sclass;
4271
4272         selinux_netlbl_sk_security_reset(newsksec);
4273 }
4274
4275 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4276 {
4277         if (!sk)
4278                 *secid = SECINITSID_ANY_SOCKET;
4279         else {
4280                 struct sk_security_struct *sksec = sk->sk_security;
4281
4282                 *secid = sksec->sid;
4283         }
4284 }
4285
4286 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4287 {
4288         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4289         struct sk_security_struct *sksec = sk->sk_security;
4290
4291         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4292             sk->sk_family == PF_UNIX)
4293                 isec->sid = sksec->sid;
4294         sksec->sclass = isec->sclass;
4295 }
4296
4297 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4298                                      struct request_sock *req)
4299 {
4300         struct sk_security_struct *sksec = sk->sk_security;
4301         int err;
4302         u16 family = sk->sk_family;
4303         u32 newsid;
4304         u32 peersid;
4305
4306         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4307         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4308                 family = PF_INET;
4309
4310         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4311         if (err)
4312                 return err;
4313         if (peersid == SECSID_NULL) {
4314                 req->secid = sksec->sid;
4315                 req->peer_secid = SECSID_NULL;
4316         } else {
4317                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4318                 if (err)
4319                         return err;
4320                 req->secid = newsid;
4321                 req->peer_secid = peersid;
4322         }
4323
4324         return selinux_netlbl_inet_conn_request(req, family);
4325 }
4326
4327 static void selinux_inet_csk_clone(struct sock *newsk,
4328                                    const struct request_sock *req)
4329 {
4330         struct sk_security_struct *newsksec = newsk->sk_security;
4331
4332         newsksec->sid = req->secid;
4333         newsksec->peer_sid = req->peer_secid;
4334         /* NOTE: Ideally, we should also get the isec->sid for the
4335            new socket in sync, but we don't have the isec available yet.
4336            So we will wait until sock_graft to do it, by which
4337            time it will have been created and available. */
4338
4339         /* We don't need to take any sort of lock here as we are the only
4340          * thread with access to newsksec */
4341         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4342 }
4343
4344 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4345 {
4346         u16 family = sk->sk_family;
4347         struct sk_security_struct *sksec = sk->sk_security;
4348
4349         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4350         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4351                 family = PF_INET;
4352
4353         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4354 }
4355
4356 static int selinux_secmark_relabel_packet(u32 sid)
4357 {
4358         const struct task_security_struct *__tsec;
4359         u32 tsid;
4360
4361         __tsec = current_security();
4362         tsid = __tsec->sid;
4363
4364         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4365 }
4366
4367 static void selinux_secmark_refcount_inc(void)
4368 {
4369         atomic_inc(&selinux_secmark_refcount);
4370 }
4371
4372 static void selinux_secmark_refcount_dec(void)
4373 {
4374         atomic_dec(&selinux_secmark_refcount);
4375 }
4376
4377 static void selinux_req_classify_flow(const struct request_sock *req,
4378                                       struct flowi *fl)
4379 {
4380         fl->flowi_secid = req->secid;
4381 }
4382
4383 static int selinux_tun_dev_create(void)
4384 {
4385         u32 sid = current_sid();
4386
4387         /* we aren't taking into account the "sockcreate" SID since the socket
4388          * that is being created here is not a socket in the traditional sense,
4389          * instead it is a private sock, accessible only to the kernel, and
4390          * representing a wide range of network traffic spanning multiple
4391          * connections unlike traditional sockets - check the TUN driver to
4392          * get a better understanding of why this socket is special */
4393
4394         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4395                             NULL);
4396 }
4397
4398 static void selinux_tun_dev_post_create(struct sock *sk)
4399 {
4400         struct sk_security_struct *sksec = sk->sk_security;
4401
4402         /* we don't currently perform any NetLabel based labeling here and it
4403          * isn't clear that we would want to do so anyway; while we could apply
4404          * labeling without the support of the TUN user the resulting labeled
4405          * traffic from the other end of the connection would almost certainly
4406          * cause confusion to the TUN user that had no idea network labeling
4407          * protocols were being used */
4408
4409         /* see the comments in selinux_tun_dev_create() about why we don't use
4410          * the sockcreate SID here */
4411
4412         sksec->sid = current_sid();
4413         sksec->sclass = SECCLASS_TUN_SOCKET;
4414 }
4415
4416 static int selinux_tun_dev_attach(struct sock *sk)
4417 {
4418         struct sk_security_struct *sksec = sk->sk_security;
4419         u32 sid = current_sid();
4420         int err;
4421
4422         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4423                            TUN_SOCKET__RELABELFROM, NULL);
4424         if (err)
4425                 return err;
4426         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4427                            TUN_SOCKET__RELABELTO, NULL);
4428         if (err)
4429                 return err;
4430
4431         sksec->sid = sid;
4432
4433         return 0;
4434 }
4435
4436 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4437 {
4438         int err = 0;
4439         u32 perm;
4440         struct nlmsghdr *nlh;
4441         struct sk_security_struct *sksec = sk->sk_security;
4442
4443         if (skb->len < NLMSG_SPACE(0)) {
4444                 err = -EINVAL;
4445                 goto out;
4446         }
4447         nlh = nlmsg_hdr(skb);
4448
4449         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4450         if (err) {
4451                 if (err == -EINVAL) {
4452                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4453                                   "SELinux:  unrecognized netlink message"
4454                                   " type=%hu for sclass=%hu\n",
4455                                   nlh->nlmsg_type, sksec->sclass);
4456                         if (!selinux_enforcing || security_get_allow_unknown())
4457                                 err = 0;
4458                 }
4459
4460                 /* Ignore */
4461                 if (err == -ENOENT)
4462                         err = 0;
4463                 goto out;
4464         }
4465
4466         err = sock_has_perm(current, sk, perm);
4467 out:
4468         return err;
4469 }
4470
4471 #ifdef CONFIG_NETFILTER
4472
4473 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4474                                        u16 family)
4475 {
4476         int err;
4477         char *addrp;
4478         u32 peer_sid;
4479         struct common_audit_data ad;
4480         u8 secmark_active;
4481         u8 netlbl_active;
4482         u8 peerlbl_active;
4483
4484         if (!selinux_policycap_netpeer)
4485                 return NF_ACCEPT;
4486
4487         secmark_active = selinux_secmark_enabled();
4488         netlbl_active = netlbl_enabled();
4489         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4490         if (!secmark_active && !peerlbl_active)
4491                 return NF_ACCEPT;
4492
4493         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4494                 return NF_DROP;
4495
4496         COMMON_AUDIT_DATA_INIT(&ad, NET);
4497         ad.u.net.netif = ifindex;
4498         ad.u.net.family = family;
4499         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4500                 return NF_DROP;
4501
4502         if (peerlbl_active) {
4503                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4504                                                peer_sid, &ad);
4505                 if (err) {
4506                         selinux_netlbl_err(skb, err, 1);
4507                         return NF_DROP;
4508                 }
4509         }
4510
4511         if (secmark_active)
4512                 if (avc_has_perm(peer_sid, skb->secmark,
4513                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4514                         return NF_DROP;
4515
4516         if (netlbl_active)
4517                 /* we do this in the FORWARD path and not the POST_ROUTING
4518                  * path because we want to make sure we apply the necessary
4519                  * labeling before IPsec is applied so we can leverage AH
4520                  * protection */
4521                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4522                         return NF_DROP;
4523
4524         return NF_ACCEPT;
4525 }
4526
4527 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4528                                          struct sk_buff *skb,
4529                                          const struct net_device *in,
4530                                          const struct net_device *out,
4531                                          int (*okfn)(struct sk_buff *))
4532 {
4533         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4534 }
4535
4536 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4537 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4538                                          struct sk_buff *skb,
4539                                          const struct net_device *in,
4540                                          const struct net_device *out,
4541                                          int (*okfn)(struct sk_buff *))
4542 {
4543         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4544 }
4545 #endif  /* IPV6 */
4546
4547 static unsigned int selinux_ip_output(struct sk_buff *skb,
4548                                       u16 family)
4549 {
4550         u32 sid;
4551
4552         if (!netlbl_enabled())
4553                 return NF_ACCEPT;
4554
4555         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4556          * because we want to make sure we apply the necessary labeling
4557          * before IPsec is applied so we can leverage AH protection */
4558         if (skb->sk) {
4559                 struct sk_security_struct *sksec = skb->sk->sk_security;
4560                 sid = sksec->sid;
4561         } else
4562                 sid = SECINITSID_KERNEL;
4563         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4564                 return NF_DROP;
4565
4566         return NF_ACCEPT;
4567 }
4568
4569 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4570                                         struct sk_buff *skb,
4571                                         const struct net_device *in,
4572                                         const struct net_device *out,
4573                                         int (*okfn)(struct sk_buff *))
4574 {
4575         return selinux_ip_output(skb, PF_INET);
4576 }
4577
4578 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4579                                                 int ifindex,
4580                                                 u16 family)
4581 {
4582         struct sock *sk = skb->sk;
4583         struct sk_security_struct *sksec;
4584         struct common_audit_data ad;
4585         char *addrp;
4586         u8 proto;
4587
4588         if (sk == NULL)
4589                 return NF_ACCEPT;
4590         sksec = sk->sk_security;
4591
4592         COMMON_AUDIT_DATA_INIT(&ad, NET);
4593         ad.u.net.netif = ifindex;
4594         ad.u.net.family = family;
4595         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4596                 return NF_DROP;
4597
4598         if (selinux_secmark_enabled())
4599                 if (avc_has_perm(sksec->sid, skb->secmark,
4600                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4601                         return NF_DROP_ERR(-ECONNREFUSED);
4602
4603         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4604                 return NF_DROP_ERR(-ECONNREFUSED);
4605
4606         return NF_ACCEPT;
4607 }
4608
4609 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4610                                          u16 family)
4611 {
4612         u32 secmark_perm;
4613         u32 peer_sid;
4614         struct sock *sk;
4615         struct common_audit_data ad;
4616         char *addrp;
4617         u8 secmark_active;
4618         u8 peerlbl_active;
4619
4620         /* If any sort of compatibility mode is enabled then handoff processing
4621          * to the selinux_ip_postroute_compat() function to deal with the
4622          * special handling.  We do this in an attempt to keep this function
4623          * as fast and as clean as possible. */
4624         if (!selinux_policycap_netpeer)
4625                 return selinux_ip_postroute_compat(skb, ifindex, family);
4626 #ifdef CONFIG_XFRM
4627         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4628          * packet transformation so allow the packet to pass without any checks
4629          * since we'll have another chance to perform access control checks
4630          * when the packet is on it's final way out.
4631          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4632          *       is NULL, in this case go ahead and apply access control. */
4633         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4634                 return NF_ACCEPT;
4635 #endif
4636         secmark_active = selinux_secmark_enabled();
4637         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4638         if (!secmark_active && !peerlbl_active)
4639                 return NF_ACCEPT;
4640
4641         /* if the packet is being forwarded then get the peer label from the
4642          * packet itself; otherwise check to see if it is from a local
4643          * application or the kernel, if from an application get the peer label
4644          * from the sending socket, otherwise use the kernel's sid */
4645         sk = skb->sk;
4646         if (sk == NULL) {
4647                 if (skb->skb_iif) {
4648                         secmark_perm = PACKET__FORWARD_OUT;
4649                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4650                                 return NF_DROP;
4651                 } else {
4652                         secmark_perm = PACKET__SEND;
4653                         peer_sid = SECINITSID_KERNEL;
4654                 }
4655         } else {
4656                 struct sk_security_struct *sksec = sk->sk_security;
4657                 peer_sid = sksec->sid;
4658                 secmark_perm = PACKET__SEND;
4659         }
4660
4661         COMMON_AUDIT_DATA_INIT(&ad, NET);
4662         ad.u.net.netif = ifindex;
4663         ad.u.net.family = family;
4664         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4665                 return NF_DROP;
4666
4667         if (secmark_active)
4668                 if (avc_has_perm(peer_sid, skb->secmark,
4669                                  SECCLASS_PACKET, secmark_perm, &ad))
4670                         return NF_DROP_ERR(-ECONNREFUSED);
4671
4672         if (peerlbl_active) {
4673                 u32 if_sid;
4674                 u32 node_sid;
4675
4676                 if (sel_netif_sid(ifindex, &if_sid))
4677                         return NF_DROP;
4678                 if (avc_has_perm(peer_sid, if_sid,
4679                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4680                         return NF_DROP_ERR(-ECONNREFUSED);
4681
4682                 if (sel_netnode_sid(addrp, family, &node_sid))
4683                         return NF_DROP;
4684                 if (avc_has_perm(peer_sid, node_sid,
4685                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4686                         return NF_DROP_ERR(-ECONNREFUSED);
4687         }
4688
4689         return NF_ACCEPT;
4690 }
4691
4692 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4693                                            struct sk_buff *skb,
4694                                            const struct net_device *in,
4695                                            const struct net_device *out,
4696                                            int (*okfn)(struct sk_buff *))
4697 {
4698         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4699 }
4700
4701 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4702 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4703                                            struct sk_buff *skb,
4704                                            const struct net_device *in,
4705                                            const struct net_device *out,
4706                                            int (*okfn)(struct sk_buff *))
4707 {
4708         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4709 }
4710 #endif  /* IPV6 */
4711
4712 #endif  /* CONFIG_NETFILTER */
4713
4714 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4715 {
4716         int err;
4717
4718         err = cap_netlink_send(sk, skb);
4719         if (err)
4720                 return err;
4721
4722         return selinux_nlmsg_perm(sk, skb);
4723 }
4724
4725 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4726 {
4727         int err;
4728         struct common_audit_data ad;
4729         u32 sid;
4730
4731         err = cap_netlink_recv(skb, capability);
4732         if (err)
4733                 return err;
4734
4735         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4736         ad.u.cap = capability;
4737
4738         security_task_getsecid(current, &sid);
4739         return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4740                             CAP_TO_MASK(capability), &ad);
4741 }
4742
4743 static int ipc_alloc_security(struct task_struct *task,
4744                               struct kern_ipc_perm *perm,
4745                               u16 sclass)
4746 {
4747         struct ipc_security_struct *isec;
4748         u32 sid;
4749
4750         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4751         if (!isec)
4752                 return -ENOMEM;
4753
4754         sid = task_sid(task);
4755         isec->sclass = sclass;
4756         isec->sid = sid;
4757         perm->security = isec;
4758
4759         return 0;
4760 }
4761
4762 static void ipc_free_security(struct kern_ipc_perm *perm)
4763 {
4764         struct ipc_security_struct *isec = perm->security;
4765         perm->security = NULL;
4766         kfree(isec);
4767 }
4768
4769 static int msg_msg_alloc_security(struct msg_msg *msg)
4770 {
4771         struct msg_security_struct *msec;
4772
4773         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4774         if (!msec)
4775                 return -ENOMEM;
4776
4777         msec->sid = SECINITSID_UNLABELED;
4778         msg->security = msec;
4779
4780         return 0;
4781 }
4782
4783 static void msg_msg_free_security(struct msg_msg *msg)
4784 {
4785         struct msg_security_struct *msec = msg->security;
4786
4787         msg->security = NULL;
4788         kfree(msec);
4789 }
4790
4791 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4792                         u32 perms)
4793 {
4794         struct ipc_security_struct *isec;
4795         struct common_audit_data ad;
4796         u32 sid = current_sid();
4797
4798         isec = ipc_perms->security;
4799
4800         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4801         ad.u.ipc_id = ipc_perms->key;
4802
4803         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4804 }
4805
4806 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4807 {
4808         return msg_msg_alloc_security(msg);
4809 }
4810
4811 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4812 {
4813         msg_msg_free_security(msg);
4814 }
4815
4816 /* message queue security operations */
4817 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4818 {
4819         struct ipc_security_struct *isec;
4820         struct common_audit_data ad;
4821         u32 sid = current_sid();
4822         int rc;
4823
4824         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4825         if (rc)
4826                 return rc;
4827
4828         isec = msq->q_perm.security;
4829
4830         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4831         ad.u.ipc_id = msq->q_perm.key;
4832
4833         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4834                           MSGQ__CREATE, &ad);
4835         if (rc) {
4836                 ipc_free_security(&msq->q_perm);
4837                 return rc;
4838         }
4839         return 0;
4840 }
4841
4842 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4843 {
4844         ipc_free_security(&msq->q_perm);
4845 }
4846
4847 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4848 {
4849         struct ipc_security_struct *isec;
4850         struct common_audit_data ad;
4851         u32 sid = current_sid();
4852
4853         isec = msq->q_perm.security;
4854
4855         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4856         ad.u.ipc_id = msq->q_perm.key;
4857
4858         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4859                             MSGQ__ASSOCIATE, &ad);
4860 }
4861
4862 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4863 {
4864         int err;
4865         int perms;
4866
4867         switch (cmd) {
4868         case IPC_INFO:
4869         case MSG_INFO:
4870                 /* No specific object, just general system-wide information. */
4871                 return task_has_system(current, SYSTEM__IPC_INFO);
4872         case IPC_STAT:
4873         case MSG_STAT:
4874                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4875                 break;
4876         case IPC_SET:
4877                 perms = MSGQ__SETATTR;
4878                 break;
4879         case IPC_RMID:
4880                 perms = MSGQ__DESTROY;
4881                 break;
4882         default:
4883                 return 0;
4884         }
4885
4886         err = ipc_has_perm(&msq->q_perm, perms);
4887         return err;
4888 }
4889
4890 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4891 {
4892         struct ipc_security_struct *isec;
4893         struct msg_security_struct *msec;
4894         struct common_audit_data ad;
4895         u32 sid = current_sid();
4896         int rc;
4897
4898         isec = msq->q_perm.security;
4899         msec = msg->security;
4900
4901         /*
4902          * First time through, need to assign label to the message
4903          */
4904         if (msec->sid == SECINITSID_UNLABELED) {
4905                 /*
4906                  * Compute new sid based on current process and
4907                  * message queue this message will be stored in
4908                  */
4909                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4910                                              NULL, &msec->sid);
4911                 if (rc)
4912                         return rc;
4913         }
4914
4915         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4916         ad.u.ipc_id = msq->q_perm.key;
4917
4918         /* Can this process write to the queue? */
4919         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4920                           MSGQ__WRITE, &ad);
4921         if (!rc)
4922                 /* Can this process send the message */
4923                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4924                                   MSG__SEND, &ad);
4925         if (!rc)
4926                 /* Can the message be put in the queue? */
4927                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4928                                   MSGQ__ENQUEUE, &ad);
4929
4930         return rc;
4931 }
4932
4933 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4934                                     struct task_struct *target,
4935                                     long type, int mode)
4936 {
4937         struct ipc_security_struct *isec;
4938         struct msg_security_struct *msec;
4939         struct common_audit_data ad;
4940         u32 sid = task_sid(target);
4941         int rc;
4942
4943         isec = msq->q_perm.security;
4944         msec = msg->security;
4945
4946         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4947         ad.u.ipc_id = msq->q_perm.key;
4948
4949         rc = avc_has_perm(sid, isec->sid,
4950                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4951         if (!rc)
4952                 rc = avc_has_perm(sid, msec->sid,
4953                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4954         return rc;
4955 }
4956
4957 /* Shared Memory security operations */
4958 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4959 {
4960         struct ipc_security_struct *isec;
4961         struct common_audit_data ad;
4962         u32 sid = current_sid();
4963         int rc;
4964
4965         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4966         if (rc)
4967                 return rc;
4968
4969         isec = shp->shm_perm.security;
4970
4971         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4972         ad.u.ipc_id = shp->shm_perm.key;
4973
4974         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4975                           SHM__CREATE, &ad);
4976         if (rc) {
4977                 ipc_free_security(&shp->shm_perm);
4978                 return rc;
4979         }
4980         return 0;
4981 }
4982
4983 static void selinux_shm_free_security(struct shmid_kernel *shp)
4984 {
4985         ipc_free_security(&shp->shm_perm);
4986 }
4987
4988 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4989 {
4990         struct ipc_security_struct *isec;
4991         struct common_audit_data ad;
4992         u32 sid = current_sid();
4993
4994         isec = shp->shm_perm.security;
4995
4996         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4997         ad.u.ipc_id = shp->shm_perm.key;
4998
4999         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5000                             SHM__ASSOCIATE, &ad);
5001 }
5002
5003 /* Note, at this point, shp is locked down */
5004 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5005 {
5006         int perms;
5007         int err;
5008
5009         switch (cmd) {
5010         case IPC_INFO:
5011         case SHM_INFO:
5012                 /* No specific object, just general system-wide information. */
5013                 return task_has_system(current, SYSTEM__IPC_INFO);
5014         case IPC_STAT:
5015         case SHM_STAT:
5016                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5017                 break;
5018         case IPC_SET:
5019                 perms = SHM__SETATTR;
5020                 break;
5021         case SHM_LOCK:
5022         case SHM_UNLOCK:
5023                 perms = SHM__LOCK;
5024                 break;
5025         case IPC_RMID:
5026                 perms = SHM__DESTROY;
5027                 break;
5028         default:
5029                 return 0;
5030         }
5031
5032         err = ipc_has_perm(&shp->shm_perm, perms);
5033         return err;
5034 }
5035
5036 static int selinux_shm_shmat(struct shmid_kernel *shp,
5037                              char __user *shmaddr, int shmflg)
5038 {
5039         u32 perms;
5040
5041         if (shmflg & SHM_RDONLY)
5042                 perms = SHM__READ;
5043         else
5044                 perms = SHM__READ | SHM__WRITE;
5045
5046         return ipc_has_perm(&shp->shm_perm, perms);
5047 }
5048
5049 /* Semaphore security operations */
5050 static int selinux_sem_alloc_security(struct sem_array *sma)
5051 {
5052         struct ipc_security_struct *isec;
5053         struct common_audit_data ad;
5054         u32 sid = current_sid();
5055         int rc;
5056
5057         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5058         if (rc)
5059                 return rc;
5060
5061         isec = sma->sem_perm.security;
5062
5063         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5064         ad.u.ipc_id = sma->sem_perm.key;
5065
5066         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5067                           SEM__CREATE, &ad);
5068         if (rc) {
5069                 ipc_free_security(&sma->sem_perm);
5070                 return rc;
5071         }
5072         return 0;
5073 }
5074
5075 static void selinux_sem_free_security(struct sem_array *sma)
5076 {
5077         ipc_free_security(&sma->sem_perm);
5078 }
5079
5080 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5081 {
5082         struct ipc_security_struct *isec;
5083         struct common_audit_data ad;
5084         u32 sid = current_sid();
5085
5086         isec = sma->sem_perm.security;
5087
5088         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5089         ad.u.ipc_id = sma->sem_perm.key;
5090
5091         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5092                             SEM__ASSOCIATE, &ad);
5093 }
5094
5095 /* Note, at this point, sma is locked down */
5096 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5097 {
5098         int err;
5099         u32 perms;
5100
5101         switch (cmd) {
5102         case IPC_INFO:
5103         case SEM_INFO:
5104                 /* No specific object, just general system-wide information. */
5105                 return task_has_system(current, SYSTEM__IPC_INFO);
5106         case GETPID:
5107         case GETNCNT:
5108         case GETZCNT:
5109                 perms = SEM__GETATTR;
5110                 break;
5111         case GETVAL:
5112         case GETALL:
5113                 perms = SEM__READ;
5114                 break;
5115         case SETVAL:
5116         case SETALL:
5117                 perms = SEM__WRITE;
5118                 break;
5119         case IPC_RMID:
5120                 perms = SEM__DESTROY;
5121                 break;
5122         case IPC_SET:
5123                 perms = SEM__SETATTR;
5124                 break;
5125         case IPC_STAT:
5126         case SEM_STAT:
5127                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5128                 break;
5129         default:
5130                 return 0;
5131         }
5132
5133         err = ipc_has_perm(&sma->sem_perm, perms);
5134         return err;
5135 }
5136
5137 static int selinux_sem_semop(struct sem_array *sma,
5138                              struct sembuf *sops, unsigned nsops, int alter)
5139 {
5140         u32 perms;
5141
5142         if (alter)
5143                 perms = SEM__READ | SEM__WRITE;
5144         else
5145                 perms = SEM__READ;
5146
5147         return ipc_has_perm(&sma->sem_perm, perms);
5148 }
5149
5150 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5151 {
5152         u32 av = 0;
5153
5154         av = 0;
5155         if (flag & S_IRUGO)
5156                 av |= IPC__UNIX_READ;
5157         if (flag & S_IWUGO)
5158                 av |= IPC__UNIX_WRITE;
5159
5160         if (av == 0)
5161                 return 0;
5162
5163         return ipc_has_perm(ipcp, av);
5164 }
5165
5166 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5167 {
5168         struct ipc_security_struct *isec = ipcp->security;
5169         *secid = isec->sid;
5170 }
5171
5172 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5173 {
5174         if (inode)
5175                 inode_doinit_with_dentry(inode, dentry);
5176 }
5177
5178 static int selinux_getprocattr(struct task_struct *p,
5179                                char *name, char **value)
5180 {
5181         const struct task_security_struct *__tsec;
5182         u32 sid;
5183         int error;
5184         unsigned len;
5185
5186         if (current != p) {
5187                 error = current_has_perm(p, PROCESS__GETATTR);
5188                 if (error)
5189                         return error;
5190         }
5191
5192         rcu_read_lock();
5193         __tsec = __task_cred(p)->security;
5194
5195         if (!strcmp(name, "current"))
5196                 sid = __tsec->sid;
5197         else if (!strcmp(name, "prev"))
5198                 sid = __tsec->osid;
5199         else if (!strcmp(name, "exec"))
5200                 sid = __tsec->exec_sid;
5201         else if (!strcmp(name, "fscreate"))
5202                 sid = __tsec->create_sid;
5203         else if (!strcmp(name, "keycreate"))
5204                 sid = __tsec->keycreate_sid;
5205         else if (!strcmp(name, "sockcreate"))
5206                 sid = __tsec->sockcreate_sid;
5207         else
5208                 goto invalid;
5209         rcu_read_unlock();
5210
5211         if (!sid)
5212                 return 0;
5213
5214         error = security_sid_to_context(sid, value, &len);
5215         if (error)
5216                 return error;
5217         return len;
5218
5219 invalid:
5220         rcu_read_unlock();
5221         return -EINVAL;
5222 }
5223
5224 static int selinux_setprocattr(struct task_struct *p,
5225                                char *name, void *value, size_t size)
5226 {
5227         struct task_security_struct *tsec;
5228         struct task_struct *tracer;
5229         struct cred *new;
5230         u32 sid = 0, ptsid;
5231         int error;
5232         char *str = value;
5233
5234         if (current != p) {
5235                 /* SELinux only allows a process to change its own
5236                    security attributes. */
5237                 return -EACCES;
5238         }
5239
5240         /*
5241          * Basic control over ability to set these attributes at all.
5242          * current == p, but we'll pass them separately in case the
5243          * above restriction is ever removed.
5244          */
5245         if (!strcmp(name, "exec"))
5246                 error = current_has_perm(p, PROCESS__SETEXEC);
5247         else if (!strcmp(name, "fscreate"))
5248                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5249         else if (!strcmp(name, "keycreate"))
5250                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5251         else if (!strcmp(name, "sockcreate"))
5252                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5253         else if (!strcmp(name, "current"))
5254                 error = current_has_perm(p, PROCESS__SETCURRENT);
5255         else
5256                 error = -EINVAL;
5257         if (error)
5258                 return error;
5259
5260         /* Obtain a SID for the context, if one was specified. */
5261         if (size && str[1] && str[1] != '\n') {
5262                 if (str[size-1] == '\n') {
5263                         str[size-1] = 0;
5264                         size--;
5265                 }
5266                 error = security_context_to_sid(value, size, &sid);
5267                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5268                         if (!capable(CAP_MAC_ADMIN))
5269                                 return error;
5270                         error = security_context_to_sid_force(value, size,
5271                                                               &sid);
5272                 }
5273                 if (error)
5274                         return error;
5275         }
5276
5277         new = prepare_creds();
5278         if (!new)
5279                 return -ENOMEM;
5280
5281         /* Permission checking based on the specified context is
5282            performed during the actual operation (execve,
5283            open/mkdir/...), when we know the full context of the
5284            operation.  See selinux_bprm_set_creds for the execve
5285            checks and may_create for the file creation checks. The
5286            operation will then fail if the context is not permitted. */
5287         tsec = new->security;
5288         if (!strcmp(name, "exec")) {
5289                 tsec->exec_sid = sid;
5290         } else if (!strcmp(name, "fscreate")) {
5291                 tsec->create_sid = sid;
5292         } else if (!strcmp(name, "keycreate")) {
5293                 error = may_create_key(sid, p);
5294                 if (error)
5295                         goto abort_change;
5296                 tsec->keycreate_sid = sid;
5297         } else if (!strcmp(name, "sockcreate")) {
5298                 tsec->sockcreate_sid = sid;
5299         } else if (!strcmp(name, "current")) {
5300                 error = -EINVAL;
5301                 if (sid == 0)
5302                         goto abort_change;
5303
5304                 /* Only allow single threaded processes to change context */
5305                 error = -EPERM;
5306                 if (!current_is_single_threaded()) {
5307                         error = security_bounded_transition(tsec->sid, sid);
5308                         if (error)
5309                                 goto abort_change;
5310                 }
5311
5312                 /* Check permissions for the transition. */
5313                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5314                                      PROCESS__DYNTRANSITION, NULL);
5315                 if (error)
5316                         goto abort_change;
5317
5318                 /* Check for ptracing, and update the task SID if ok.
5319                    Otherwise, leave SID unchanged and fail. */
5320                 ptsid = 0;
5321                 task_lock(p);
5322                 tracer = tracehook_tracer_task(p);
5323                 if (tracer)
5324                         ptsid = task_sid(tracer);
5325                 task_unlock(p);
5326
5327                 if (tracer) {
5328                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5329                                              PROCESS__PTRACE, NULL);
5330                         if (error)
5331                                 goto abort_change;
5332                 }
5333
5334                 tsec->sid = sid;
5335         } else {
5336                 error = -EINVAL;
5337                 goto abort_change;
5338         }
5339
5340         commit_creds(new);
5341         return size;
5342
5343 abort_change:
5344         abort_creds(new);
5345         return error;
5346 }
5347
5348 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5349 {
5350         return security_sid_to_context(secid, secdata, seclen);
5351 }
5352
5353 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5354 {
5355         return security_context_to_sid(secdata, seclen, secid);
5356 }
5357
5358 static void selinux_release_secctx(char *secdata, u32 seclen)
5359 {
5360         kfree(secdata);
5361 }
5362
5363 /*
5364  *      called with inode->i_mutex locked
5365  */
5366 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5367 {
5368         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5369 }
5370
5371 /*
5372  *      called with inode->i_mutex locked
5373  */
5374 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5375 {
5376         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5377 }
5378
5379 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5380 {
5381         int len = 0;
5382         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5383                                                 ctx, true);
5384         if (len < 0)
5385                 return len;
5386         *ctxlen = len;
5387         return 0;
5388 }
5389 #ifdef CONFIG_KEYS
5390
5391 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5392                              unsigned long flags)
5393 {
5394         const struct task_security_struct *tsec;
5395         struct key_security_struct *ksec;
5396
5397         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5398         if (!ksec)
5399                 return -ENOMEM;
5400
5401         tsec = cred->security;
5402         if (tsec->keycreate_sid)
5403                 ksec->sid = tsec->keycreate_sid;
5404         else
5405                 ksec->sid = tsec->sid;
5406
5407         k->security = ksec;
5408         return 0;
5409 }
5410
5411 static void selinux_key_free(struct key *k)
5412 {
5413         struct key_security_struct *ksec = k->security;
5414
5415         k->security = NULL;
5416         kfree(ksec);
5417 }
5418
5419 static int selinux_key_permission(key_ref_t key_ref,
5420                                   const struct cred *cred,
5421                                   key_perm_t perm)
5422 {
5423         struct key *key;
5424         struct key_security_struct *ksec;
5425         u32 sid;
5426
5427         /* if no specific permissions are requested, we skip the
5428            permission check. No serious, additional covert channels
5429            appear to be created. */
5430         if (perm == 0)
5431                 return 0;
5432
5433         sid = cred_sid(cred);
5434
5435         key = key_ref_to_ptr(key_ref);
5436         ksec = key->security;
5437
5438         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5439 }
5440
5441 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5442 {
5443         struct key_security_struct *ksec = key->security;
5444         char *context = NULL;
5445         unsigned len;
5446         int rc;
5447
5448         rc = security_sid_to_context(ksec->sid, &context, &len);
5449         if (!rc)
5450                 rc = len;
5451         *_buffer = context;
5452         return rc;
5453 }
5454
5455 #endif
5456
5457 static struct security_operations selinux_ops = {
5458         .name =                         "selinux",
5459
5460         .ptrace_access_check =          selinux_ptrace_access_check,
5461         .ptrace_traceme =               selinux_ptrace_traceme,
5462         .capget =                       selinux_capget,
5463         .capset =                       selinux_capset,
5464         .capable =                      selinux_capable,
5465         .quotactl =                     selinux_quotactl,
5466         .quota_on =                     selinux_quota_on,
5467         .syslog =                       selinux_syslog,
5468         .vm_enough_memory =             selinux_vm_enough_memory,
5469
5470         .netlink_send =                 selinux_netlink_send,
5471         .netlink_recv =                 selinux_netlink_recv,
5472
5473         .bprm_set_creds =               selinux_bprm_set_creds,
5474         .bprm_committing_creds =        selinux_bprm_committing_creds,
5475         .bprm_committed_creds =         selinux_bprm_committed_creds,
5476         .bprm_secureexec =              selinux_bprm_secureexec,
5477
5478         .sb_alloc_security =            selinux_sb_alloc_security,
5479         .sb_free_security =             selinux_sb_free_security,
5480         .sb_copy_data =                 selinux_sb_copy_data,
5481         .sb_remount =                   selinux_sb_remount,
5482         .sb_kern_mount =                selinux_sb_kern_mount,
5483         .sb_show_options =              selinux_sb_show_options,
5484         .sb_statfs =                    selinux_sb_statfs,
5485         .sb_mount =                     selinux_mount,
5486         .sb_umount =                    selinux_umount,
5487         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5488         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5489         .sb_parse_opts_str =            selinux_parse_opts_str,
5490
5491
5492         .inode_alloc_security =         selinux_inode_alloc_security,
5493         .inode_free_security =          selinux_inode_free_security,
5494         .inode_init_security =          selinux_inode_init_security,
5495         .inode_create =                 selinux_inode_create,
5496         .inode_link =                   selinux_inode_link,
5497         .inode_unlink =                 selinux_inode_unlink,
5498         .inode_symlink =                selinux_inode_symlink,
5499         .inode_mkdir =                  selinux_inode_mkdir,
5500         .inode_rmdir =                  selinux_inode_rmdir,
5501         .inode_mknod =                  selinux_inode_mknod,
5502         .inode_rename =                 selinux_inode_rename,
5503         .inode_readlink =               selinux_inode_readlink,
5504         .inode_follow_link =            selinux_inode_follow_link,
5505         .inode_permission =             selinux_inode_permission,
5506         .inode_setattr =                selinux_inode_setattr,
5507         .inode_getattr =                selinux_inode_getattr,
5508         .inode_setxattr =               selinux_inode_setxattr,
5509         .inode_post_setxattr =          selinux_inode_post_setxattr,
5510         .inode_getxattr =               selinux_inode_getxattr,
5511         .inode_listxattr =              selinux_inode_listxattr,
5512         .inode_removexattr =            selinux_inode_removexattr,
5513         .inode_getsecurity =            selinux_inode_getsecurity,
5514         .inode_setsecurity =            selinux_inode_setsecurity,
5515         .inode_listsecurity =           selinux_inode_listsecurity,
5516         .inode_getsecid =               selinux_inode_getsecid,
5517
5518         .file_permission =              selinux_file_permission,
5519         .file_alloc_security =          selinux_file_alloc_security,
5520         .file_free_security =           selinux_file_free_security,
5521         .file_ioctl =                   selinux_file_ioctl,
5522         .file_mmap =                    selinux_file_mmap,
5523         .file_mprotect =                selinux_file_mprotect,
5524         .file_lock =                    selinux_file_lock,
5525         .file_fcntl =                   selinux_file_fcntl,
5526         .file_set_fowner =              selinux_file_set_fowner,
5527         .file_send_sigiotask =          selinux_file_send_sigiotask,
5528         .file_receive =                 selinux_file_receive,
5529
5530         .dentry_open =                  selinux_dentry_open,
5531
5532         .task_create =                  selinux_task_create,
5533         .cred_alloc_blank =             selinux_cred_alloc_blank,
5534         .cred_free =                    selinux_cred_free,
5535         .cred_prepare =                 selinux_cred_prepare,
5536         .cred_transfer =                selinux_cred_transfer,
5537         .kernel_act_as =                selinux_kernel_act_as,
5538         .kernel_create_files_as =       selinux_kernel_create_files_as,
5539         .kernel_module_request =        selinux_kernel_module_request,
5540         .task_setpgid =                 selinux_task_setpgid,
5541         .task_getpgid =                 selinux_task_getpgid,
5542         .task_getsid =                  selinux_task_getsid,
5543         .task_getsecid =                selinux_task_getsecid,
5544         .task_setnice =                 selinux_task_setnice,
5545         .task_setioprio =               selinux_task_setioprio,
5546         .task_getioprio =               selinux_task_getioprio,
5547         .task_setrlimit =               selinux_task_setrlimit,
5548         .task_setscheduler =            selinux_task_setscheduler,
5549         .task_getscheduler =            selinux_task_getscheduler,
5550         .task_movememory =              selinux_task_movememory,
5551         .task_kill =                    selinux_task_kill,
5552         .task_wait =                    selinux_task_wait,
5553         .task_to_inode =                selinux_task_to_inode,
5554
5555         .ipc_permission =               selinux_ipc_permission,
5556         .ipc_getsecid =                 selinux_ipc_getsecid,
5557
5558         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5559         .msg_msg_free_security =        selinux_msg_msg_free_security,
5560
5561         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5562         .msg_queue_free_security =      selinux_msg_queue_free_security,
5563         .msg_queue_associate =          selinux_msg_queue_associate,
5564         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5565         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5566         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5567
5568         .shm_alloc_security =           selinux_shm_alloc_security,
5569         .shm_free_security =            selinux_shm_free_security,
5570         .shm_associate =                selinux_shm_associate,
5571         .shm_shmctl =                   selinux_shm_shmctl,
5572         .shm_shmat =                    selinux_shm_shmat,
5573
5574         .sem_alloc_security =           selinux_sem_alloc_security,
5575         .sem_free_security =            selinux_sem_free_security,
5576         .sem_associate =                selinux_sem_associate,
5577         .sem_semctl =                   selinux_sem_semctl,
5578         .sem_semop =                    selinux_sem_semop,
5579
5580         .d_instantiate =                selinux_d_instantiate,
5581
5582         .getprocattr =                  selinux_getprocattr,
5583         .setprocattr =                  selinux_setprocattr,
5584
5585         .secid_to_secctx =              selinux_secid_to_secctx,
5586         .secctx_to_secid =              selinux_secctx_to_secid,
5587         .release_secctx =               selinux_release_secctx,
5588         .inode_notifysecctx =           selinux_inode_notifysecctx,
5589         .inode_setsecctx =              selinux_inode_setsecctx,
5590         .inode_getsecctx =              selinux_inode_getsecctx,
5591
5592         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5593         .unix_may_send =                selinux_socket_unix_may_send,
5594
5595         .socket_create =                selinux_socket_create,
5596         .socket_post_create =           selinux_socket_post_create,
5597         .socket_bind =                  selinux_socket_bind,
5598         .socket_connect =               selinux_socket_connect,
5599         .socket_listen =                selinux_socket_listen,
5600         .socket_accept =                selinux_socket_accept,
5601         .socket_sendmsg =               selinux_socket_sendmsg,
5602         .socket_recvmsg =               selinux_socket_recvmsg,
5603         .socket_getsockname =           selinux_socket_getsockname,
5604         .socket_getpeername =           selinux_socket_getpeername,
5605         .socket_getsockopt =            selinux_socket_getsockopt,
5606         .socket_setsockopt =            selinux_socket_setsockopt,
5607         .socket_shutdown =              selinux_socket_shutdown,
5608         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5609         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5610         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5611         .sk_alloc_security =            selinux_sk_alloc_security,
5612         .sk_free_security =             selinux_sk_free_security,
5613         .sk_clone_security =            selinux_sk_clone_security,
5614         .sk_getsecid =                  selinux_sk_getsecid,
5615         .sock_graft =                   selinux_sock_graft,
5616         .inet_conn_request =            selinux_inet_conn_request,
5617         .inet_csk_clone =               selinux_inet_csk_clone,
5618         .inet_conn_established =        selinux_inet_conn_established,
5619         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5620         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5621         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5622         .req_classify_flow =            selinux_req_classify_flow,
5623         .tun_dev_create =               selinux_tun_dev_create,
5624         .tun_dev_post_create =          selinux_tun_dev_post_create,
5625         .tun_dev_attach =               selinux_tun_dev_attach,
5626
5627 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5628         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5629         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5630         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5631         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5632         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5633         .xfrm_state_free_security =     selinux_xfrm_state_free,
5634         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5635         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5636         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5637         .xfrm_decode_session =          selinux_xfrm_decode_session,
5638 #endif
5639
5640 #ifdef CONFIG_KEYS
5641         .key_alloc =                    selinux_key_alloc,
5642         .key_free =                     selinux_key_free,
5643         .key_permission =               selinux_key_permission,
5644         .key_getsecurity =              selinux_key_getsecurity,
5645 #endif
5646
5647 #ifdef CONFIG_AUDIT
5648         .audit_rule_init =              selinux_audit_rule_init,
5649         .audit_rule_known =             selinux_audit_rule_known,
5650         .audit_rule_match =             selinux_audit_rule_match,
5651         .audit_rule_free =              selinux_audit_rule_free,
5652 #endif
5653 };
5654
5655 static __init int selinux_init(void)
5656 {
5657         if (!security_module_enable(&selinux_ops)) {
5658                 selinux_enabled = 0;
5659                 return 0;
5660         }
5661
5662         if (!selinux_enabled) {
5663                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5664                 return 0;
5665         }
5666
5667         printk(KERN_INFO "SELinux:  Initializing.\n");
5668
5669         /* Set the security state for the initial task. */
5670         cred_init_security();
5671
5672         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5673
5674         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5675                                             sizeof(struct inode_security_struct),
5676                                             0, SLAB_PANIC, NULL);
5677         avc_init();
5678
5679         if (register_security(&selinux_ops))
5680                 panic("SELinux: Unable to register with kernel.\n");
5681
5682         if (selinux_enforcing)
5683                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5684         else
5685                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5686
5687         return 0;
5688 }
5689
5690 static void delayed_superblock_init(struct super_block *sb, void *unused)
5691 {
5692         superblock_doinit(sb, NULL);
5693 }
5694
5695 void selinux_complete_init(void)
5696 {
5697         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5698
5699         /* Set up any superblocks initialized prior to the policy load. */
5700         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5701         iterate_supers(delayed_superblock_init, NULL);
5702 }
5703
5704 /* SELinux requires early initialization in order to label
5705    all processes and objects when they are created. */
5706 security_initcall(selinux_init);
5707
5708 #if defined(CONFIG_NETFILTER)
5709
5710 static struct nf_hook_ops selinux_ipv4_ops[] = {
5711         {
5712                 .hook =         selinux_ipv4_postroute,
5713                 .owner =        THIS_MODULE,
5714                 .pf =           PF_INET,
5715                 .hooknum =      NF_INET_POST_ROUTING,
5716                 .priority =     NF_IP_PRI_SELINUX_LAST,
5717         },
5718         {
5719                 .hook =         selinux_ipv4_forward,
5720                 .owner =        THIS_MODULE,
5721                 .pf =           PF_INET,
5722                 .hooknum =      NF_INET_FORWARD,
5723                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5724         },
5725         {
5726                 .hook =         selinux_ipv4_output,
5727                 .owner =        THIS_MODULE,
5728                 .pf =           PF_INET,
5729                 .hooknum =      NF_INET_LOCAL_OUT,
5730                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5731         }
5732 };
5733
5734 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5735
5736 static struct nf_hook_ops selinux_ipv6_ops[] = {
5737         {
5738                 .hook =         selinux_ipv6_postroute,
5739                 .owner =        THIS_MODULE,
5740                 .pf =           PF_INET6,
5741                 .hooknum =      NF_INET_POST_ROUTING,
5742                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5743         },
5744         {
5745                 .hook =         selinux_ipv6_forward,
5746                 .owner =        THIS_MODULE,
5747                 .pf =           PF_INET6,
5748                 .hooknum =      NF_INET_FORWARD,
5749                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5750         }
5751 };
5752
5753 #endif  /* IPV6 */
5754
5755 static int __init selinux_nf_ip_init(void)
5756 {
5757         int err = 0;
5758
5759         if (!selinux_enabled)
5760                 goto out;
5761
5762         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5763
5764         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5765         if (err)
5766                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5767
5768 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5769         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5770         if (err)
5771                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5772 #endif  /* IPV6 */
5773
5774 out:
5775         return err;
5776 }
5777
5778 __initcall(selinux_nf_ip_init);
5779
5780 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5781 static void selinux_nf_ip_exit(void)
5782 {
5783         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5784
5785         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5786 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5787         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5788 #endif  /* IPV6 */
5789 }
5790 #endif
5791
5792 #else /* CONFIG_NETFILTER */
5793
5794 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5795 #define selinux_nf_ip_exit()
5796 #endif
5797
5798 #endif /* CONFIG_NETFILTER */
5799
5800 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5801 static int selinux_disabled;
5802
5803 int selinux_disable(void)
5804 {
5805         extern void exit_sel_fs(void);
5806
5807         if (ss_initialized) {
5808                 /* Not permitted after initial policy load. */
5809                 return -EINVAL;
5810         }
5811
5812         if (selinux_disabled) {
5813                 /* Only do this once. */
5814                 return -EINVAL;
5815         }
5816
5817         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5818
5819         selinux_disabled = 1;
5820         selinux_enabled = 0;
5821
5822         reset_security_ops();
5823
5824         /* Try to destroy the avc node cache */
5825         avc_disable();
5826
5827         /* Unregister netfilter hooks. */
5828         selinux_nf_ip_exit();
5829
5830         /* Unregister selinuxfs. */
5831         exit_sel_fs();
5832
5833         return 0;
5834 }
5835 #endif